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MECANIQUE    CELESTE. 


MECANIQUE    CELESTE. 


BY  THE 


MARQUIS   DE  LA  PLACE, 

PEER  OF  FRANCE;   GRAND  CROSS  OF  THE  LEGION  OF  HONOR  ;  MEMBER  OF  THE  FRENCH  ACADEMY,    OF  THE  ACADEMY 

OF    SCIENCES    OF    PARIS,   OF    THE    BOARD    OF    LONGITUDE    OF    FRANCE,    OF    THE    ROYAL    SOCIETIES    OF 

LONOON    AND    GOTTINGEN,    OF    THE    ACADEMIES    OF    SCIENCES    OF    RUSSIA,    DENMARK. 

SWEDEN,    PRUSSIA,  HOLLAND,  AND    ITALY;    MEMBER   OF   THE 

AMERICAN    ACADEMY    OF    ARTS    AND   SCIENCES;    ETC. 


TRANSLATED,  WITH  A  COMMENTARY, 


NATHANIEL    BOWDITCH,    LL.  D. 

TELLOW    OF    THE    ROYAL    SOCIETIES    OF    LONDON,    EDINBURGH,    AND    DUBLIN;     OF    THE    ASTRONOMICAL    SOCIETY 

OF    LONDON  j     OF    THE    PHILOSOPHICAL    SOCIETY    HELD    AT    PHILADELPHIA;    OF    THE 

AMERICAN    ACADEMY    OF    ARTS    AND    SCIENCES  J    ETC. 


VOLUME     III. 


BOSTON  : 

FROM    THE    PRESS    OF    ISAAC    R.     BUTTS  ; 

MILLIARD,  GRAY,  LITTLE,  AND  WILKINS,  PUBLISHERS. 
M  DCCC  XXXIV. 


/i^i 


/ 


fâb"^ 


Entered,  according  to  Act  of  Congress,  in  the  year   1829, 

By  Nathaniel  Bowditch, 
in  the  Clerk's  Office  of  the  District  Court  of  Massachusetts. 


TO 


BONAPARTE 


MEMBER   OF   THE   NATIONAL   INSTITUTE. 


Citizen  First  Consul, 

You  have  permitted  me  to  dedicate  this  work  to  you. 
It  is  gratifying  and  honorable  to  me  to  present  it  to  the  Hero,  the 
Pacificator  of  Europe,*  to  whom  France  owes  her  prosperity,  her  greatness, 
and  the  most  brilliant  epoch  of  her  glory  ;  to  the  enlightened  Protector 
of  the  Sciences,  who,  himself  distinguished  in  them,  perceives,  in  their 
cultivation,  the  source  of  the  most  noble  enjoyment,  and,  in  their 
progress,  the  perfection  of  all  useful  arts  and  social  institutions. 
May  this  work,  consecrated  to  the  most  sublime  of  the  natural  sciences, 
be  a  durable  monument  of  the  gratitude  inspired  in  those  who  cultivate 
them,  by  your  kindness,  and  by  the  rewards  of  the  government. 
Of  all  the  truths  which  this  work  contains,  the  expression  of  this 
sentiment  will  ever  be  the  most  precious  to  me. 

Salutation  and  Respect, 

LA  PLACE. 


[*  This  volume  was  published,  by  La  Place,  in  1802,  soon  after  the  peace  of  Amiens.] 
VOL.   III.  B 


ADVERTISEMENT. 


This  volume  contains  the  numerical  values  of  the  secular  and  periodical 
inequalities  of  the  motions  of  the  planets  and  moon  ;  the  numbers,  given 
in  the  original  work,  having  been  reduced  from  centesimal  to  sexagesimal 
seconds,  to  render  them  more  convenient  for  reference.  The  Appendix 
contains  many  important  formulas  and  tables,  which  are  useful  to 
astronomers  in  computing  the  motions  of  the  planets  and  comets.  Some  of 
these  tables  are  new,  and  the  others  have  been  varied  in  their  forms,  to 
render  them  more  simple  in  their  uses  and  applications  :  none  of  them  have 
heretofore  been  published  in  this  country.  Several  of  the  formulas  have 
been  introduced  into  the  calculations  of  modern  astronomy,  since  the 
commencement  of  the  first  part  of  the  original  work.  The  portrait  of 
the  author,  accompanying  this  volume,  was  obtained  in  France,  and  is  an 
impression  from  the  original  plate,  which  was  engraved  under  his  direction, 
for  the  Système  du  Monde.  The  fourth  volume  of  the  work  will  be  put 
to  press  in  the  course  of  a  few  weeks. 


PREFACE. 


We  have  given,  in  the  first  part  of  this  work,  the  general  principles  of 
the  equilibrium  and  motion  of  bodies.  The  application  of  these  principles 
to  the  motions  of  the  heavenly  bodies,  has  conducted  us,  by  geometrical 
reasoning,  without  any  hypothesis,  to  the  law  of  universal  attraction  ;  the 
action  of  gravity,  and  the  motions  of  projectiles  on  the  surface  of  the  earth, 
being  particular  cases  of  this  law.  We  have  then  taken  into  consideration, 
a  system  of  bodies  subjected  to  this  great  law  of  nature  ;  and  have  obtained, 
by  a  singular  analysis,  the  general  expressions  of  their  motions,  of  their 
figures,  and  of  the  oscillations  of  the  fluids  which  cover  them.  From  these 
expressions,  we  have  deduced  all  the  known  phenomena  of  the  flow  and  ebb 
of  the  tide  ;  the  variations  of  the  degrees,  and  of  the  force  of  gravity  at  the 
surface  of  the  earth  ;  the  precession  of  the  equinoxes  ;  the  libration  of  the 
moon  ;  and  the  figure  and  rotation  of  Saturn's  Rings.  -We  have  also  pointed 
out  the  cause,  why  these  rings  remain,  permanently,  in  the  plane  of  the 
equator  of  Saturn.  Moreover,  we  have  deduced,  from  the  same  theory  of 
gravity,  the  principal  equations  of  the  motions  of  the  planets  ;  particularly 
those  of  Jupiter  and  Saturn,  whose  great  inequalities  have  a  period  of  above 
nine  hundred  years.  The  inequalities  in  the  motions  of  Jupiter  and  Saturn, 
presented,  at  first,  to  astronomers,  nothing  but  anomalies,  whose  laws  and 
causes  were  unknown;  and,  for  a  long  time,  these  irregularities  appeared  to 
be  inconsistent  with  the  theory  of  gravity  ;  but  a  more  thorough  examination 
has  shown,  that  they  can  be  deduced  from  it  ;  and  now,  these  motions   are 

VOL.   III.  c 


PREFACE. 

one  of  the  most  striking  proofs  of  the  truth  of  this  theory.  We  have 
developed  the  secular  variations  of  the  elements  of  the  planetary  system, 
which  do  not  return  to  the  same  state  till  after  the  lapse  of  many  centuries. 
In  the  midst  of  all  these  changes  we  have  discovered  the  constancy  of  the 
mean  motions,  and  of  the  mean  distances  of  the  bodies  of  this  system  ; 
which  nature  seems  to  have  arranged,  at  its  origin,  for  an  eternal  duration, 
upon  the  same  principles  as  those  which  prevail,  so  admirably,  upon  the 
earth,  for  the  preservation  of  individuals,  and  for  the  perpetuity  of  the 
species.  From  the  single  circumstance,  that  the  motions  are  all  in  the 
same  direction,  and  in  planes  but  little  inclined  to  each  other,  it  follows, 
that  the  orbits  of  the  planets  and  satellites  must  always  be  nearly  circular, 
and  but  little  inclined  to  each  other.  Thus,  the  variations  of  the  obliquity 
of  the  ecliptic,  which  are  always  included  within  narrow  limits,  will  never 
produce  an  eternal  spring  upon  the  earth.  We  have  proved  that  the  attraction 
of  the  terrestrial  spheroid,  by  incessantly  drawing  towards  its  centre 
the  hemisphere  of  the  moon,  which  is  directed  towards  the  earth,  transfers 
to  the  rotatory  motion  of  this  satellite,  the  great  secular  variations  of  its 
motion  of  revolution  ;  and,  by  this  means,  keeps  always  from  our  view,  the 
other  hemisphere.  Lastly,  we  have  demonstrated,  in  the  motions  of  the 
three  first  satellites  of  Jupiter,  the  following  remarkable  law,  namely, 
that,  in  consequence  of  their  mutual  attractions,  the  mean  longitude  of  the 
first  satellite,  seen  from  the  centre  of  Jupiter,  minus  three  times  that  of  the 
second  satellite,  plus  twice  that  of  the  third  satellite,  is  alivays  exactly  equal 
to  two  right  angles  ;  so  that  they  cannot  all  be  eclipsed  at  the  same  time. 
It  remains  now  to  consider  particularly  the  perturbations  of  the  motions  of 
the  planets  and  comets  about  the  sun  ;  of  the  moon  about  the  earth  ;  and 
of  the  satellites  about  their  primary  planets.  This  is  the  object  of  the 
second  part  of  this  work,  which  is  particularly  devoted  to  the  improvement 
of  astronomical  tables. 


PREFACE.  xi 

The  tables  have  followed  the  progress  of  the  science,  which  serves  as 
their  basis  ;  and  this  progress  was,  at  first,  extremely  slow.  During  a  very 
long  time,  the  apparent  motions  only  of  the  planets  were  observed.  This 
interval,  which  commenced  in  the  most  remote  antiquity,  may  be  considered 
as  the  infancy  of  Astronomy.  It  comprises  the  labors  of  Hipparchus  and 
Ptolemy  ;  also,  those  of  the  Indians,  the  Arabs,  and  the  Persians.  The 
system  of  Ptolemy,  which  they  successively  adopted,  is,  in  fact,  nothing 
more  than  a  method  of  representing  the  apparent  motions  ;  and,  on  this 
account,  it  was  useful  to  science.  Such  is  the  weakness  of  the  human 
mind,  that  it  often  requires  the  aid  of  a  theory,  to  connect  together 
a  series  of  observations.  If  we  restrict  the  theory  to  this  use,  and 
take  care  not  to  attribute  to  it  a  reality  which  it  does  not  possess,  and 
afterwards  frequently  rectify  it,  by  new  observations,  we  may  finally  discover 
the  true  cause,  or,  at  least,  the  laws  of  the  phenomena.  The  history  of 
Philosophy  affords  us  more  than  one  example,  of  the  advantages  which  may 
be  derived  from  an  assumed  theory  ;  and,  of  the  errors  to  Avhich  we  are 
exposed,  in  considering  it  to  be  the  true  representation  of  nature.  About 
the  middle  of  the  sixteenth  century,  Copernicus  discovered,  that  the 
apparent  motions  of  the  heavenly  bodies  indicated  a  real  motion  of  the 
earth  about  the  sun,  with  a  rotatory  motion  about  its  own  axis  :  by  this 
means,  he  showed  to  us  the  universe  in  a  new  point  of  view,  and  completely 
changed  the  face  of  Astronomy.  A  remarkable  concurrence  of  discoveries 
will  forever  render  memorable,  in  the  history  of  science,  the  century 
immediately  following  this  discovery  ;  a  period  which  is  also  illustrious,  by 
many  master-pieces  of  literature  and  the  fine  arts.  Kepler  discovered  the 
laws  of  the  elliptical  motion  of  the  planets  ;  the  telescope,  which  was 
invented  by  the  most  fortunate  accident,  and  was  immediately  improved 
by  Galileo,  enabled  him  to  see,  in  the  heavens,  new  inequalities  and  new 
worlds.     The  application  of  the  pendulum  to  clocks,  by  Huygens,  and  that 


xii  PREFACE. 

of  telescopes  to  the  astronomical    quadrant,   gave  more  accurate  measures 

of  angles  and  times,  and  thus  rendered  sensible  the  least  inequalities  in  the 

celestial   motions.      At  the  same  time   that  observations  presented  to  the 

human  mind   new  phenomena,  it  created,  to  explain  them,  and  to  submit 

them     to    calculation,    new    instruments    of  thought.       Napier    invented 

logarithms  :    the  analysis  of   curves,  and   the   science  of   dynamics,  were 

formed   I)y   the   hands   of  Descartes  and   Galileo  :  Newton  discovered  the 

differential  calculus,  decomposed  a  ray  of  light,   and  penetrated   into  the 

general  principle   of  gravity.     In  the  century  which  has  just  passed,  the 

successors  of  this  great  man  have  finished  the  superstructure,  of  which  he 

laid  the  foundation.      They  have   improved  the  analysis   of  infinitely  small 

quantities,  and  have  invented  the  calculus  of  partial  differences,  both  infinitely 

small  and  finite  :    and   have    reduced  the   whole  science    of  mechanics   to 

formulas.     In  applying  these  discoveries  to  the  law  of  gravity,  they  have 

deduced  from  it  all  the  celestial  phenomena  ;  and  have  given  to  the  theories 

and  to  astronomical  tables  an  unexpected  degree  of  accuracy;  which  is   to 

be   attributed,  in  a  great  measure,  to  the  labors  of  French  mathematicians, 

and    to    the    prizes  proposed    by  the    Academy    of    Sciences.      To  these 

discoveries    in    the    last    century,     we    must    add     those  of    Bradley,  on 

the  aberration  of  the  stars,  and   on  the  nutation  of  the  earth's  axis  :  the 

numerous  measures  of  the  degrees  of  the    meridian,   and  of  the  lengths  of 

the  pendulum  ;  of  which  operations,  the  first  example  was  given  by  France, 

in  sending  academicians  to  the  north,  to  the  equator,  and   to  the  southern 

hemisphere,   to  observe  the  lengths  of  these  degrees,  and  the   intensity  of 

gravity  :    the    measure   of   the  arc  of   the    meridian,     comprised   between 

Dunkirk  and    Barcelona  ;     which   has  been   determined   by   very  accurate 

observation,   and    is    used  as    the    basis    of   the    most  simple  and  natural 

system  of    measures  :    the  numerous  voyages  of  discovery,  undertaken  to 

explore    the  different  parts    of   the  globe,    and  to  observe  the  transits  of 


PREFACE.  xiii 

Venus  over  the  sun's  disc  ;  by  which  means,  the  exact  determination  of 
the  dimensions  of  the  sokir  system  has  been  obtained,  as  the  fruit  of 
these  voyages  :  the  discoveries,  by  Herschel,  of  the  planet  Uranus,  its 
satellites,  and  two  new  satellites  of  Saturn  :  finally,  if  we  add  to  all  these 
discoveries,  the  admirable  invention  of  the  instrument  of  reflexion,  so  useful 
at  sea  ;  that  of  the  achromatic  telescope  ;  also  the  repeating  circle,  and 
chronometer  ;  we  must  be  satisfied,  that  the  last  century,  considered 
with  respect  to  the  progress  of  the  human  mind,  is  worthy  of  that 
which  preceded  it.  The  century  we  have  now  entered  upon,  commenced 
under  the  most  favorable  auspices  for  Astronomy.  Its  first  day  was 
remarkable,  by  the  discovery  of  the  planet  Ceres  ;  followed,  almost 
immediately  afterwards,  by  that  of  the  planet  Pallas,  having  nearly  the 
same  mean  distance  from  the  sun.  The  proximity  of  Jupiter  to  these  two 
extremely  small  bodies  ;  the  greatness  of  the  excentricities  and  of  the 
inclinations  of  their  mutually  intersecting  orbits,  must  produce,  in  their 
motions,  considerable  inequalities,  which  will  throw  new  light  on  the 
theory  of  the  celestial  attractions,  and  must  give  rise  to  farther  improvements 
in  Astronomy. 

It  is  chiefly  in  the  application  of  analysis  to  the  system  of  the  world, 
that  we  perceive  the  power  of  this  wonderful  instrument  ;  without  which, 
it  would  have  been  impossible  to  have  discovered  a  mechanism  which  is 
so  complicated  in  its  effects,  while  it  is  so  simple  in  its  cause.  The 
mathematician  now  includes  in  his  formulas,  the  whole  of  the  planetary 
system,  and  its  successive  variations  ;  he  looks  back,  in  imagination,  to  the 
several  states,  which  the  system  has  passed  through,  in  the  most  remote 
ages  ;  and  foretells  what  time  will  hereafter  make  known  to  observers. 
He  sees  this  sublime  spectacle,  whose  period  includes  several  millions  of 
years,  repeated   in  a    few   centuries,    in  the    system    of    the    satellites    of 

VOL.    HI.  D 


XIV  PREFACE. 

Jupiter,  by  means  of  the  rapidity  of  their  revolutions  ;  which  produce 
remarkable  phenomena,  similar  to  those  which  had  been  suspected,  by 
astronomers,  in  the  planetary  motions  ;  but  had  not  been  determined, 
because  they  were  either  too  complex,  or  too  slow,  for  an  accurate 
determination  of  their  laws.  The  tlieory  of  gravity,  which,  by  so  many 
applications,  has  become  a  means  of  discovery,  as  certain  as  by  observation 
itself,  has  made  known  to  him  several  new  inequalities,  in  the  motions  of  the 
heavenly  bodies,  and  enabled  him  to  predict  the  return  of  the  comet  of  1 759, 
whose  revolutions  are  rendered  very  unequal,  by  the  attractions  of  Jupiter 
and  Saturn.  He  has  been  enabled,  by  this  means,  to  deduce,  from 
observation,  as  from  a  rich  mine,  a  great  number  of  important  and  delicate 
elements,  which,  without  the  aid  of  analysis,  would  have  been  forever 
hidden  from  his  view:  such  as  the  relative  values  of  the  masses  of  the 
sun,  the  planets  and  satellites,  determined  by  the  revolutions  of  these  bodies, 
and  by  the  development  of  their  periodical  and  secular  inequalities  : 
the  velocity  of  light,  and  the  ellipticity  of  Jupiter  ;  which  are  given, 
by  the  eclipses  of  its  satellites,  with  greater  accuracy,  than  by  direct 
observation:  the  rotation  and  oblateness  of  Uranus  and  Saturn;  deduced 
from  the  consideration,  that  the  different  bodies  which  revolve  about 
those  two  planets,  are  in  the  same  plane,  respectively  :  the  parallaxes 
of  the  sun  and  moon  :  and,  also,  the  figure  of  the  earth,  deduced  from 
some  lunar  inequalities  :  for,  we  shall  see  hereafter,  that  the  moon,  by 
its  motion,  discloses  to  modern  astronomy,  the  small  ellipticity  of  the 
terrestrial  spheroid,  whose  roundness  was  made  known  to  the  first  observers 
by  the  eclipses  of  that  luminary.  Lastly,  by  a  fortunate  combination  of 
analysis  with  observation,  that  body,  which  seems  to  have  been  given  to 
the  earth,  to  enlighten  it,  during  the  night,  becomes  also  the  most  sure 
guide  of  the  navigator  ;  who  is  protected  by  it  from  the  dangers,  to 
\vhich  he  was  for  a  long  time  exposed,    by  the  errors  of    his  reckoning. 


PREFACE.  XV 

The  perfection  of  the  theory,  and  of  the  lunar  tables,  to  which  he  is 
indebted  for  this  important  object,  and  for  that  of  determining,  with 
accuracy,  the  position  of  the  places  he  falls  in  with,  is  the  fruit  of  the 
labors  of  mathematicians  and  astronomers,  during  the  last  fifty  years: 
it  unites  all  that  can  give  value  to  a  discovery  ;  the  importance  and 
usefulness  of  the  object,  its  various  applications,  and  the  merit  of  the 
dififlculty  which  is  overcome.  It  is  thus,  that  the  most  abstract  theories, 
diffused  by  numerous  applications  to  nature  and  to  the  arts,  have  become 
inexhaustible  sources  of  comfort  and  enjoyment,  even  to  those  who  are 
wholly  ignorant  of  the  nature  of  these  theories. 


CONTENTS  OF  THE  THIRD  VOLUME. 


PARTICULAR  THEORIES  OP  THE  MOTIONS  OF  THE  HEAVENLY  BODIES. 


SIXTH   BOOK. 

THEORY  OF  THE  PLANETARY  MOTIONS. 
Object  of  this  theory 1 

CHAPTER  I.  FORMULAS  FOR  THE  INEaUALITIES  OF  THE  MOTIONS  OP  THE  PLANETS,  WHICH 
DEPEND  ON  THE  SaUARES  AND  HIGHER  POWERS  OF  THE  EXCENTRICITIES  AND  INCLINATIONS  OF 
THE  ORBITS 4 

ON     TUE    INEaUALITIES      WHICH     DEPEND     UPON     THE      SaUARES     AND     PRODUCTS      OP     THE 
EXCENTRICITIES   AND  INCLINATIONS 4 

Form  of  the  terms  which  produce  them  [.3703,3704].  Influence  of  the  ratio  of  the  mean 
motions  upon  these  terms,  by  reason  of  the  small  divisors,  which  are  introduced  by  the 
integrations  [3712].  Preparations  of  the  diflerential  equations  for  the  different  cases  of  these 
inequalities  which  occur  in  the  solar  system §L2 

Considerations,  by  which  we  may  distinguish  the  most  important  of  these  inequalities 
[3732-3735] §3 

Development  of  the  terms,  which  result  in  the  expressions  of  the  radius  vector,  of  the  longitude, 
and  of  the  latitude  of  the  disturbed  planet  [3736— 3800] §4,5,0 

OX  THE  INEaUALITIES  DEPENDING  ON  THE  CUBES  AND  PRODUCTS  OF  THREE  DIMENSIONS  OF  THE 
EXCENTRICITIES  AND  INCLINATIONS  OF  THE  ORBITS,  AND  ON  THEIE  HIGHER  POWERS 45 

Form  of  the  terms  which  produce  them  [3807—3807'] §  7 

Examination  of  the  cases  where  they  become  sensible.  They  depend  on  the  circumstance,  that 
the  ratios  of  the  mean  motions  are  nearly  commensurable.  Application  of  these  principles  to 
the  theory  of  Jupiter  and  Saturn,  in  terras  of  the  third  degree  [3828,  &c.] §  8 

Inequalities  depending  on  terms  of  the  fifth  degree  [38.56'].  They  are  sensible  in  the  theory  of 
Jupiter  and  Saturn.     Calculation  of  them  for  these  planets  [3860,  «Sic] §  9 

VOL.    MI.  E 


XX  CONTENTS  OF  THE  THIRD  VOLUME. 

longitude  and  the  radius  vector  of  the  earth  [4300', 4304].     The  planets  which  produce  them, 
are  Venus,  Mars,  Jupiter  and  Saturn. 

Inequalities  which  are  independent  of  the  excentricities  [4305,4306]. 

Inequalities  depending  on  the  first  power  of  the  excentricities  [4307, 4308]. 

Inequalities  depending  on  tlie  second  dimension  of  the  excentricities  and  inclinations  of  the 
orbits  [4309]. 

Inequalities  depending  on  the  third  dimension  of  the  same  quantities  [4311]. 

Inequalities  of  the  motion  of  the  earth  in  latitude  [4312].  They  are  produced  by  the  action  of 
Venus  and  Jupiter ^  2<j 

Inequalities  of  the  motion  of  the  Earth,  produced  by  the  action  of  the  Moon  [4324,4326].      §30 

On  the  secular  variations  of  the  earth's  orbit,  of  the  equator,  and  of  the  length  of  the  year 
[4329",  &c.].  The  action  of  the  sun  and  moon  has  a  considerable  influence  on  these  values. 
Determination  of  the  epoch,  when  the  greater  axis  of  the  earth's  orbit  coincided  with  the  line 
of  the  equinoxes  [4363"],  and  when  these  two  lines  were  perpendicular  to  each  other 
[4367'"] §31 

CHAPTER  XI.    THEORY  OF  MAES 26S 

Examination  of  the  limit  to  which  the  approximations  must  be  carried,  in  the  valuation  of  the 
radius  vector  [4371,  &c.].  Numerical  values  of  the  sensible  inequalities  which  affect  the 
longitude  and  radius  vector.  The  planets  which  produce  them,  are  Venus,  the  Earth,  Jupiter 
and  Saturn. 

Inequalities  which  are  independent  of  the  excentricities  [4.373,  4374]. 

Inequalities  depending  on  the  first  power  of  the  excentricities  [4375, 4376]. 

Inequalities  depending  on  the  second  dimension  of  the  excentricities  and  inclinations  of  the 
orbits  [4377—4380]. 

The  inequalities  in  latitude  are  hardly  sensible  [4384].  The  greatest  of  them  arises  from  the 
action  of  Jupiter §32 

CHAPTER  Xll.      THEORY  OF  JUPITER 275 

Examination  of  the  limit  to  which  the  approximations  must  be  carried,  in  the  valuation  of  the 
radius  vector  [4385,  &c.].  Numerical  values  of  the  sensible  inequalities  afiecting  the 
longitude  and  the  radius  vector.  The  planets  which  produce  these  inequalities,  are  the  Earth, 
Saturn,  and  Uranus,  but  chiefly  Saturn. 

Inequalities  which  are  independent  of  the  e.xcentricities  [4388,4389]. 

Inequalities  depending  on  the  first  power  of  the  excentricities  [4392,4393].  They  are  so  large 
as  to  render  it  necessary  to  notice  the  variation  of  their  coefiîcients. 

Inequalities  depending  on  the  squares  and  products  of  the  excentricities  and  inclinations 
[4.394 — 4.397],     They  are  produced  only  by  the  action  of  Saturn. 


CONTENTS  OF  THE  THIRD  VOLUME.  Xxi 

Inequalities  depending  on  the  third  and  fifth  dimensions  of  the  excentricities  and  inclinations  ; 
and  also  on  the  square  of  the  disturbing  force  [4401,  «fee.].  These  last  terms,  which  depend 
on  the  inequalities  of  a  very  long  period,  have  considerable  influence  on  the  secular  variations 
of  the  elliptical  elements. 

Great  inequality  of  the  mean  motions  [4434].    It  is  produced  by  the  action  of  Saturn.     .     §33 

Inequalities  in  latitude  [4457].     They  are  produced  by  the  action  of  Saturn §34 

CHAPTER     XIII.    THEOUV  OF  SATURi\ 299 

Examination  of  the  degree  to  which  the  approximations  must  be  carried  in  the  valuation  of  the 
radius  vector  [4460,  &c.].  Numerical  valuesof  the  sensible  inequalities  affecting  the  longitude 
and  radius  vector.    The  planets  which  produce  them  are  Jupiter  and  Uranus. 

Inequalities  which  are  independent  of  the  excentricities  [4463,446]. 

Inequalities  depending  on  the  first  power  of  the  excentricities  [4466,  4467]. 

Inequalities  depending  on  the  squares  and  products  of  the  excentricities  and  inclinations 
[4463—4471]. 

Inequalities  depending  on  the  third  and  fifth  dimensions  of  the  excentricities  and  inclinations, 
and  also  on  the  square  of  the  disturbing  force  [4472',  &c].  Great  inequality  of  Saturn.  It  is 
the  reaction  of  that  of  Jupiter §  35 

Inequalities  in  latitude  [4511].    They  are  produced  by  the  action  of  Jupiter  and  Uranus.     .   §-36 

CHAPTER  XIV.     THEORY  OF  UEANUS 314 

Examination  of  the  degree  to  which  the  approximations  must  be  carried,  in  the  valuation  of  the 
radius  vector  [4521,  &c.].  Numerical  values  of  the  sensible  inequalities  affecting  the 
longitude  and  radius  vector.     They  are  produced  by  the  action  of  Jupiter  and  Saturn. 

Inequalities  which  are  independent  of  the  excentricities  [4523, 4524]. 

Inequalities  depending  on  the  first  power  of  the  excentricities  [4525, 4526]. 

Inequalities  depending  on  the  second  dimension  of  the  excentricities  and  inclinations 
[4.527—4529]. 

Inequalities  depending  on  the  third   dimension  of  the  excentricities  and  inclinations   [4530]. 
There  is  only  one  of  them  produced  by  the  action  of  Saturn §  37 

Inequalities  in  latitude  [4531].     They  are  produced  by  the  action  of  Jupiter  and  Saturn.      §  38 

CHAPTER  XV.     O.N  SOME  EaUATIONS  OF  CONDITION,  BETWEEN  THE  INEaUALlTlES  OF  THE  PLANETS, 

WHICH  MAY  BE  USED  IN  VEEIFn.NG  THEIR  NUMERICAL  VALCES §39—43    318 

CHAPTER  XVI.    ON  THE  MASSES  OF  THE  PLANETS  AND  MOON 333 

VOL.    III.  F 


XXII 


CONTENTS  OF  THE  THIRD  VOLUME. 

Reflections  on  the  values  given  to  those  masses  in  §  21.  New  determination  of  those  of  Venus 
and  Mars  [4G05,  4608].  Discussion  of  that  of  the  Moon,  by  the  comparison  of  several 
phenomena  which  can  determine  it  [4619  —  4637],  such  as  the  observation  of  the  tides,  the 
lunar  equation  in  the  tables  of  the  Sun,  the  nutation  of  the  Earth's  axis,  and  the  Moon's 
parallax.  From  these  examinations,  it  appears,  that  this  mass  is  rather  less  than  that  which  is 
deduced  from  the  tides  observed  at  Brest  [4037] §44 

* 
CHAPTER  XVII.    ON  THE  FORMATION  OF  ASTRONOMICAL  TABLES,  AND  ON  THE  INVARIABLE  PLANE 

OF  THE  PLANETARY  SVSTEM §45,46    341 

CHAPTER  XVIII.    ON  THE  ACTION  OF  THE  FIXED  STARS  UPON  THF  PLANETARY  SYSTEM.    .     .     .    343 

The  great  distance  of  these  bodies  renders  their  action  insensible  [4673].  Reflections  on  the 
comparison  of  the  preceding  formulas  with  observations  [4687,  &c.] §47 


SEVENTH    BOOK. 


THEORY  OF  THE  MOON. 

Explanation  of  this  theory  ;  its  particular  difficulties  [4692,  &c.].  Considerations  that  must  influence 
us  in  the  approximations.  How  we  may  deduce  from  this  theory,  several  important  elements 
of  the  system  of  the  world  [4702,  &c.],  and  among  others,  the  oblateness  of  the  Earlh  [4709], 
which  is  thus  obtained  with  greater  accuracy  than  by  direct  observations 356 

CHAPTER    I.    INTEGRATION  OF  THE  DIFFERENTIAL  EaUATIONS  OF  THE  MOON'S  MOTION 2QQ 

Difierential  equations  of  this  motion  given  in  §  15  of  the  second  book  [4753  —  4756].  Method 
of  noticing  in  the  calculation,  the  non-sphericity  of  the  Moon  and  Earth  [4773].     ...     §  1 

Development  of  the  quantities  which  occur  in  the  differential  equations,  supposing  these  two 
bodies  to  be  spherical  [4780,  &c.] §2 

The  ecliptic,  in  its  secular  motion,  carries  with  it  the  moon's  orbit,  so  that  the  mean  inclination  of 
this  orbit  to  the  ecliptic,  remains  always  the  same  [4803].  This  circumstance,  indicated  by 
analysis,  simplifies  the  calculations,  because  it  permits  us  to  take  the  ecliptic  for  the  fixed  plane 
of  projection  [4804] §3 

Investigation  of  the  elliptical  part  of  the  motions  of  the  Moon  and  Earth  [4826, 4828, 4837,4838].  §  4 

Principles  relative  to  the  degrees  of  smallness  of  the  quantities  which  occur  in  the  expressions 
of  the  co-ordinates  of  the  moon  [4841].  Examination  of  the  influence  of  the  successive 
integrations  upon  the  different  terms  of  these  co-ordinates  [4847,  &c.].  Indication  of  the 
terms  of  the  radius  vector,  wliich  produce  the  evection  [4850],  and  annual  equation  [4851].  §5 


CONTENTS  OF  THE  THIRD  VOLUME.  Xxiii 

Use  to  be  made  of  these  considerations.  Development  of  the  differential  equation  which  produces 
the  radius  vector  ;  noticing  only  the  first  power  of  the  disturbing  force  [4858  —  4903].     §  6,  7 

Investigation  of  the  terms  of  the  order  of  the  square  and  the  higher  powers  of  the  disturbing 
masses,  which  acquire  a  sensible  influence  by  integration  [4904,  &c.].  It  is  necessary  to 
notice  the  perturbations  of  the  Earth  by  the  Moon  [4909',  4948,  &c.] §8 

Connection  of  these  terms  with  the  preceding.  Complete  development  of  the  differential 
equation  which  produces  the  radius  vector  [4961] §  9 

Integration  of  tliis  equation  [4904,  &c.].  Inequalities  resulting  from  it.  Expression  of  the 
motion  of  the  lunar  perigee  [4982,  &c.]. 

The  variableness  of  the  excentricity  of  the  Earth's  orbit  produces  a  secular  inequality  in  the 
constant  term  of  the  Moon's  parallax  ;  but  this  inequality  is  insensible  [4970]. 

The  same  cause  produces  a  secular  inequality  in  the  motion  of  the  Moon's  perigee,  which  is 
conformable  to  observation.     Analytical  expression  of  this  inequality  [4985]. 

The  excentricity  of  the  Moon's  orbit  is  subjected  to  a  secular  variation,  which  is  analogous  to 
that  of  the  parallax,  and  like  it,  insensible  [4987] §  10 

Development  of  the  differential  equation  which  gives  the  latitude  [501 8,  &c.],  noticing,  in  the 
first  place,  only  the  simple  power  of  the  disturbing  forces §11 

Investigation  of  tlie  terms  of  the  order  of  the  square  of  those  forces  which  acquire  a  sensible 
influence  in  the  expression  of  the  latitude  [5039,&c.] §12 

Connection  of  these  terms  with  the  preceding,  and  the  complete  development  of  the  difierential 
equation  which  gives  the  latitude  [5049] §13 

Integration  of  this  equation  [5050,  &c.].  Inequalities  resulting  from  it.  Expression  of  the 
retrograde  motion  of  the  nodes  [5059]. 

The  variableness  of  the  excentricity  of  the  Earth's  orbit,  produces  in  this  motion  a  secular 
inequality.  Analytical  expression  of  this  inequality  [5059].  Its  ratio  to  that  of  the  perigee 
[5060]. 

The  inclination  of  the  lunar  orbit  to  the  true  ecliptic,  is  likewise  variable  by  means  of  the  same 
cause  ;  but  this  variation  is  insensible  [50G1] §14 

Development  of  the  differential  equation  which  gives  the  time  or  the  mean  longitude  in  terras  of 
the  true  longitude  [5081,  &c.]  Integration  of  this  equation.  Inequalities  which  result  from 
it  [5095,  &c.] 

The  mean  longitude  also  suffers  a  secular  change,  resulting  from  the  variableness  of  the  excentricity 
of  the  Earth's  orbit;  expression  of  this  inequality.  Analytical  relations  of  the  secular  equations 
of  the  mean  motions  of  the  Moon,  its  perigee  and  nodes  [5089,  «Sic] §  15 

Numerical  determination  of  the  several  coefficients,  occurring  in  the  preceding  formulas  [51 17,&c.] 
and  the  numerical  développent  of  the  expression  of  the  mean  longitude  [5220].  The 
perturbations  of  the  Earth's  orbit  by  the  Moon,  are  reflected  to  the  Moon  by  means  of  the  Sun 
and  are  weakened  by  the  transmission  [.5225,  5226].  Numerical  value  of  tlie  motion  of  the 
perigee  [5231],  and  of  its  secular  equation  [5232].  This  equation  has  a  contrary  sign  to  that 
of  the  mean  motion  [.5232'].     Numerical  expression  of  the  motion  of  the  node  [5233],  and  of 


Xxiv  CONTENTS  OF  THE  THIRD  VOLUME. 

its  secular  equation  [5234].  This  equation  has  also  a  contrary  sign  to  that  of  the  mean  motion 
[5234']  ;  hence  it  follows,  that  the  motions  of  the  nodes  and  perigee  decrease,  while  that  of  the 
Moon  increases.  Numerical  ratios  of  these  three  secular  equations  [5235].  Secular  equation 
of  the  mean  anomaly  [5238] §  16 

The  most  sensible  inequalities  of  the  fourth  order,  which  occur  in  the  expression  of  tlie  mean 
longitude  [5240— 5305] §17 

Numerical  expression  of  the  latitude  [5308] §18 

Numerical  expression  of  the  Moon's  parallax  [5331] §  19 

CHAPTER  II.    ON  THE  LUÎJAR  INEQUALITIES  ARISING  FROM  THE  OBLATENESS  OF  THE   EARTH   A.\D 

MOON 585 

The  oblateness  of  the  Earth  produces  in  the  latitude  of  the  Moon  but  one  single  inequality.  We 
may  represent  this  effect,  by  supposing  that  the  orbit  of  the  Moon,  instead  of  moving  on  the 
plane  of  the  ecliptic,  with  a  constant  inclination,  to  move  with  the  same  condition,  upon  a 
plane  which  always  passes  through  the  equinoxes  between  the  ecliptic  and  equator  [5352]. 
This  inequality  can  be  used  for  the  determination  of  the  oblateness  of  the  Earth  [.5358].  It 
is  the  reaction  of  the  nutation  of  the  Earth's  axis  upon  the  lunar  spheroid  [5398],  and  there 
would  be  an  equilibrium  about  the  centre  of  gravity  of  the  Earth  by  means  of  the  forces 
producing  these  two  inequalities,  if  all  the  particles  of  the  Earth  and  Moon  were  firmly 
connected  with  each  other,  the  Moon  compensating  for  the  sraallness  of  the  forces  acting  on  it, 
by  the  length  of  the  lever  to  which  it  is  attached  [5424]. 

The  oblatenes  of  the  Earth  has  no  sensible  influence  on  the  radius  vector  of  the  Moon  [.53G6]  ; 
but  it  produces  in  the  Moon's  longitude  one  sensible  inequality.  The  motions  of  the  perigee 
and  node  are  but  very  little  augmented  by  it  [5396,  &c.] §  20 

The  non-sphericity  of  the  Moon  produces  in  its  motion  only  insensible  inequalities 
[5445,  5451,  &c.] §21 

CHAPTER  III.    ON  THE  INEaUALITIES  OP  TUE  MOON  DEPENDING  ON  THE  ACTION  OF  THE  PLANETS.  G17 

These  inequalities  are  of  two  kinds,  the  first  depends  on  the  direct  action  of  the  planets  on  the 
motion  of  the  Moon  [5479,  5481]  ;  the  second  arises  from  the  perturbations  in  the  Earth's 
radius  vector  produced  by  the  planets  [5490].  These  perturbations  are  reflected  to  the  Moon 
by  means  of  the  Sun,  and  are  augmented  by  the  integrations  which  gives  them  small  divisors. 
Determination  of  these  inequalities  for  Venus,  Mars,  and  Jupiter  [5491,  &c.].  The  variableness 
of  the  excentricities  of  the  orbits  of  the  planets,  introduces,  in  the  mean  longitude  of  the 
Moon,  secular  equations,  analogous  to  that  produced  by  the  variation  of  the  excentricity  of  the 
Earth's  orbit,  reflected  to  the  Moon  by  means  of  the  Sun  ;  but  they  are  wholly  insensible  in 
comparison  with  this  last.  Thus  the  indirect  action  of  the  planets  on  the  Moon,  transmitted  by 
means  of  the  Sun,  considerably  exceeds  their  direct  action,  relative  to  this  inequality  [5539].  §22 

CHAPTER  IV.    COMPARISON  OF  THE  PRECEDING  THEORY  WITH  OBSERVATION 642 

Numerical  values  of  the  secular  inequality  of  the  mean  motion  of  the  Moon  [5542,  &c.],  and  those 
of  the  mean  motions  of  the  perigee  and  node  of  the  Moon's  orbit.  Considerations  which 
confirm  their  accuracy  [5544,  &c.] §  23 


CONTENTS   OF  THE  THIRD  VOLUME. 

Periodical  inequalities  of  the  Moon's  motion  in  longitude  [5551,  &c.].  Agreement  of  the 
coefficients  given  by  the  theory,  with  those  of  the  lunar  tables  of  Mason  and  Burg  [5575,  &c.]. 
One  of  these  inequalities  depends  on  the  Sun's  parallax  [5581].  If  we  determine  its 
coefficient  by  observation,  we  may  deduce  from  it  the  same  value  of  the  Sun's  paralla.ï,as  that 
which  is  obtained  by  the  transits  of  Venus  [5589'].  Another  of  these  inequalities  depends  on 
the  oblateness  of  the  Earth  [5590].  The  value  of  its  coefficient  determined  by  the  tables  of 
Mason  and  Burg,  indicates  that  the  Earth  is  less  flattened  than  in  the  hypothesis  of  homogeneity, 
and  that  the  oblatenes  is     ^^-g.     [5593] , S  34 

Inequalities  of  the  Moon's  motion  in  latitude  [5595,  &c.].  Agreement  of  the  coefficients  given 
by  the  theory  with  those  of  the  tables  of  Mason  and  Burg  [5596].  One  of  these  inequalities 
depends  on  the  oblateness  of  the  Earth  [5598].  Its  coefficient,  determined  by  observation, 
gives  tlie  same  oblateness  [5602],  as  the  inequality  in  longitude  depending  on  the  same  element. 
So  that  these  two  results  agree  in  proving,  that  the  Earth  is  less  flattened  than  in  the 
hypothesis  of  homogeneity ^25 

Numerical  expression  of  the  Moon's  horizontal  parallax  [5C03].  Its  agreement  with  the  tables 
of  Mason  and  Burg  [5605] §26 

CHAPTER  V.     ON    AN  INEaUALITV  OF  A  LONG  PERIOD,  WHICH  APPEARS  TO  EXIST  IN  THE   MOON'S 

MOTION QQQ 

The  action  of  the  Sun  on  the  Moon,  produces  in  the  motion  of  that  satellite  an  inequality,  whose 
argument  is  double  the  longitude  of  the  node  of  the  Moon's  orbit,  plus  the  longitude  of  its 
perigee,  mimis  three  times  the  longitude  of  the  Sun's  perigee  [5641,  &c.].  The  consideration 
of  the  non-spherical  form  of  the  Earth,  may  also  introduce  into  the  motion  of  the  Moon,  two 
other  inequalities  [5633,  5638'],  with  nearly  the  same  period  as  that  which  we  have  just 
mentioned  ;  and  in  the  present  situation  of  the  Sun's  perigee,  they  are  all  three  nearly 
confounded  together.  The  coefficients  of  these  three  inequalities  are  very  difficult  to  compute 
from  the  theory  ;  it  appears  that  the  two  last  must  be  wholly  insensible  [5637',  5639'].     .     §  27 

The  first  is  evidently  indicated  by  observations.  Determination  of  its  coefficient  [5665].  [This 
result  was  afterwards  found  to  be  incorrect,  as  is  observed  in  the  note,  page  666,  &c.].      §  28 

CHAPTER   VI.     ON  THE  SECULAR  VARIATIONS  OF  THE  MOTIONS  OF  THE  MOON  AND  EARTH,  WHICH 

CAN  BE  PRODUCED  BY  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID  SURROUNDING  THE  SUN.     .     .    g-^g 

The  resistance  of  the  ether  produces  a  secular  equation  in  the  Moon's  mean  motion  [5715]  ; 
but  it  does  not  produce  any  sensible  inequality  in  the  motions  of  the  perigee  and  nodes 
[5713,5717] §29 

The  secular  equation  of  the  Earth's  mean  motion,  produced  by  the  resistance  of  the  ether,  is  about 
one  hundredth  part  of  the  corresponding  equation  of  the  Moon's  mean  motion  [5740].  §30 


VOL.   III.  ^ 


XXV 


Xxvi  CONTENTS   OF   THE   THIRD   VOLUME. 


APPENDIX    BY    THE    AUTHOR. 

The  chief  object  of  this  appendix  is  to  demonstrate  a  theorem,  discovered  by  Mr.  Poisson,  that  the 
mean  motions  of  the  planets  are  invariable,  when  we  notice  only  the  terms  depending  on  the  first  and 
second  powers  of  the  disturbing  forces  [5744,  &c.]  This  is  done  by  giving  new  forms  to  some  of  the 
differential  expressions  of  the  elements  of  the  orbits,  as  is  observed  in  [.5743,  &c].  Forms  of  these 
differentials,  including  all  the  terms  depending  upon  the  first  power  of  the  disturbing  masses 
[5786 — 5791].  Expressions  of  the  mean  motion  [5794]  ;  of  the  periodical  inequalities  in  the 
elements  [5873 — 5879]  ;  and  of  the  secular  inequalities  of  the  elements  [5882 — 58SS]. 

Investigation  of  the  mutual  action  of  two  planets  upon  each  other,  referring  their  inequalities  to 
an  intermediate  invariable  plane  [5905,  &c]. 

New  method  of  computing  the  lunar  inequalities,  depending  upon  the  oblateness  of  the  earth 
[5937—5973]. 

On  the  two  great  inequalities  of  Jupiter  and  Saturn  ;  correcting  for  the  mistake  in  the  signs  of  the 
functions  JVC),  JV(})  Sic.  [5974—5981]. 


IN    THE    COMMENTARY 


Among  the  subjects  treated  of  in  the  JVotes,  we  may  mention  the  following  : 

Correction  to  be  made  in  the  formula  mfàR-{-m'rdR'  =  0,  [1202],  in  some  of  the  terms  of  the 
order  of  the  square  of  the  disturbing  masses  [4004c,  &c].  The  necessity  of  this  correction  was  first 
made  known  by  Mr.  Plana  [400Gw,  &c.].  Results  of  the  discussion  upon  this  subject,  by  Messrs. 
Plana,  Pontecoulant,  Poisson  and  La  Place  [40056'— 4008î].  New  formula  by  La  Place,  relative  to 
some  of  these  terms  [4008x].  This  formula  has  been  called  "  the  last  gift  of  La  Place  to  Astronomy," 
being  the  last  work  he  ever  published. 

On  the  values  of  the  constant  quantities  f,,f',g,  &c.  ;  introduced  into  the  integral  expressions  of 
or,  ÔV,  OS,  by  La  Place  [4058c,  &c.]  ;  which  were  objected  to  by  Mr.  Plana.  The  results  of  La  Place's 
calculation  proved  to  be  correct  by  him,  and  by  Mr.  Poisson,  in  [4058c — 40G0/i]. 

Corrected  values  of  the  masses  of  the  planets,  finally  adopted  by  the  author  [40Gld]. 

Elements  of  the  newly  discovered  planets  Vesta,  Juno,  Pallas  and  Ceres  ;  corresponding  to  the  23d 
July,  1831,  as  given  by  Enckc  [4079i]. 

Elements  of  the  orbits  of  the  comets  of  Halley,  Olbers,  Encke  and  Biela  [4079»i]. 

Inequalities  in  the  motions  of  Venus  and  the  Earth,  having  a  period  of  2.39  years,  and  depending 
on  terms  of  the  fifth  order  of  the  excentricities  and  inclinations  ;  discovered  and  computed  by  Professor 
Airy  [4296  a  —  q,  4310  c  — /]. 

Mr.  Ponteooulant's  table  of  the  part  of  the  great  inequality  of  the  motion  of  Jupiter,  depending  on 
the  square  of  the  disturbing  force  [4431/].  Similar  table  for  the  inequalities  of  the  motion  of  Saturn 
[4489c]. 

Results  of  the  calculations  of  Professor  Hansen  [4489  n  —  p]. 


CONTENTS    OF    THE    THIRD    VOLUME.  XXvii 

The  action  of  the  fixed  stars  affects  the  accuracy  of  the  equation  ta.  m.  \/ n -(- c's.  ?)i'.  y/a' -f- &c.  =  0 
[46S5g-]. 

Results  of  the  calculations  of  several  authors  relative  to  the  sun's  parallax,  hy  means  of  the  parallactic 
inequality  in  the  moon's  longitude,  and  by  the  transits  of  Venus  over  the  sun's  disc  [5589  a  —  m]. 

Inequality  in  the  moon's  longitude,  whose  period  is  about  179  years.  It  is  found  to  be  insensible 
[5611  a  —  g];  instead  of  being  15V39  at  its  maximum,  as  the  author  supposes  in  [5GG5]. 

The  planets  and  comets  move  in  a  resisting  medium,  according  to  the  observations  of  Encke's 
comet  [5067  a —  c]. 

Notice  of  the  papers  published  by  La  Grange  and  Poisson,  relative  to  the  invaiiableness  of  the  mean 
motions  of  the  planets,  which  is  treated  of  in  the  appendix  to  this  volume  [5741a  —  I]. 

It  appears  from  the  calculations  of  Nicolai,  Encke  and  Airy,  that  the  estimated  value  of  the  mass  of 
Jupiter,  adopted  by  La  Place  from  Bouvard's  calculations  of  its  action  on  Saturn  and  Uranus,  must  be 
increased,  to  satisfy  the  observed  perturbations  of  the  planets  Juno  and  "Vesta  ;  as  well  as  those  of 
Encke's  comet,  [5980  i — p]. 


APPENDIX  BY  THE  TRANSLATOR. 

Formulas  for  the  motion  of  a  body  in  an  elliptical  orbit  [.5985(1—19)]  ;    with    their   demonstrations 
[5984(3-25)]. 
Formulas  for  the  motion  of  a  body  in  a  parabolic  orbit  [5986]  ;  with  their  demonstrations  [5987]. 
Determination  of  the  symbol   log.  A:  =  8,2355814  ..  .    which  is  used  in  these  calculations  [5987(8)]. 
Formulas  for  the  motions  of  a  body  in  a  hyperbolic  orbit  [5988]  ;  with  their  demonstrations  [5989]. 
Kepler's  problem  for  computing  the  true  anomaly  from  the  time,  or  the  contrary,   in  an  elliptic  orbit. 

Indirect  solution  of  this  problem,   according   to  Kepler's  method,  but  arranged  in  formulas 

by  Gauss  [.5990]. 

Simpson's  method  for  determining  the  true  anomaly,  in  an  ellipsis  or  hyperbola,  where   e   is 

very  nearly  equal  to  unity,  noticing  only  the  first  power  of    1  —  t,    or    e  —  J  [5991(1— 12)]. 

Bessel's  improved  method  for  computing   the   terms  depending  on  the  second   power  of 

1  -e    or    e-1  [.5991(1-40)] 

Gauss's  method,  in  a  very  cxcentric  ellipsis,  noticing  all  the  powers  of   e  —  1  [5992]. 

Gauss's  method  of  solution  in  a  hyperbolic  orbit,  in  which    e  —  1    is  very  small,  noticing 

all  tlie  powers  of  this  quantity  [5993]. 

Olbers's  method  of  computing  the  orbit  of  a  comet  [.5994,  &c.]. 

Table  of  formulas  which  are  used  in  this  calculation  [5994(.9— 45)]. 

Geometrical  investigation  of  this  method  of  calculation  [5994(46—130")]. 

Remarks  on  the  manner  of  determining  the  approximate  values  of  the  curtate    distance    p 

of  the  comet  from  the  earth  [5994(132—172)] 

Examples  for  illustrating  these  calculations  [5994(173—242)  ],  using  tables  I,  II,  III. 

Remarks  on  the  calculation  of  p   by  means  of  the  equations    (C),  (/))  [.5994(136—103,  242',  242")]. 

Forms  of  the  fundamental  equations,  adopted  by  Gauss  for  the  determination  of  the  curtate  distance, 
or  its  equivalent  expression    it,    by  means  of  logarithms  [5994(244,  &c.)]. 

Solution  of  two  examples,  reduced  to  the  form  of  Gauss  [5994(247 — 250)]. 

Analytical  investigation  of  the  method  of  computing  the  orbit  of  a  comet,  [5994(263-403)]. 

Great  advantage  in  having  the  intervals  of  times  between  the  observations  nearly  equal  to  each 
other  [5994(349)]. 


XXVÏn  CONTENTS  OF  THE  THIRD  VOLUME. 

The  method  usually  employed  in  this  calculation  requires  some  modification,  when  M  appears 
under  the  form  of  a  fraction,  in  which  the  numerators  and  denominators  are  both  very  small 
[5994(257)].     These  methods  are  explained  in  [5994(387—392)]. 

Mr.  Lubbock's  method  of  computing  the  orbit  of  a  comet  [5994(405—458)]. 

Method  of  computing  the  elements  of  the  orbit  of  a  heavenly  body;  there  being  given  the  two 
radii  r,r',  the  intermediate  angle  v'  —  v  =  2f,  and  the  time  f  —  t  of  describing  the  angle  2/ 
[5995]. 

Collection  of  formulas  for  solving  this  problem,  in  an  elliptical  orbit  [5995(4—67)]  ;  with  their 
demonstrations  [5995(08—174)].     Examples  of  the  uses  of  these  formulas  [5995(175—193)]. 

Collection  of  formulas  for  solving  this  problem  in  a  parabolic  orbit  [5996(2— :i;5)]  ;  with  their 
demonstrations  [.5996(26—50)]  ;  illustrated  by  an  example  in  [5996(51-53)]. 

Collection  of  formulas  for  solving  this  problem  in  a  hyperbolic  orbit  [5997(1 — 59)]  ;  with  their 
demonstrations  [5997(60—172)].     Example  of  the  uses  of  these  formulas  [5997(173—183)]. 

Gauss's  method  of  correcting  for  the  efiect  of  the  parallax  and  aberration  of  any  newly  discovered 
planet  or  comet,  in  computing  its  orbit  by  means  of  throe  geocentric  observations,  with  the  intervals 
of  time  between  them  [5998]. 

Corrections  in  the  places  of  the  earth,  on  account  of  the  planet's  parallax  [5998(47 — 50)]. 

Method  of  calculating  the  longitude  and  latitude  of  the  zenith  [5998(67 — 71)&,c.];  also  the 
longitude  and  latitude  of  the  planet  from  its  right  ascension  and  declination  [5998  (97— 107)  ],  with 
examples. 

Method  of  correcting  for  the  aberration  of  the  planet  [5998(108 — 117)]. 

Example  for  illustrating  the  calculations  relative  to  the  parallax  and  aberration  [5998(118 — 126)]. 

Gauss's  method  of  computing  the  orbit  of  a  planet  or  comet,  by  means  of  three  geocentric  longitudes 
and  latitudes,  together  with  the  times  of  observation  [5999.] 

Table  of  the  symbols  and  formulas  which  are  used  in  this  method  [5999(9 — 54)]. 

Demonstrations  of  these  formulas  [5999(58,  &c.)]. 

Example,  containing  the  whole  calculation  of  the  elements  of  the  orbit  of  Juno,  from  three  observa- 
tions of  Maskelyne  [5999(274—650)]. 


CATALOGUE  OF  THE  TABLES  IN  THE  APPENDIX. 

Table  i.  Contains  the  square  roots  of  the  numbers  from  0,001  to  10,1  ;  to  be  used  in  Olbers's 
method  of  computing  the  orbit  of  a  comet  ;  in  finding  r,  r",  c  ;  from  j-9,  r"%  c^  ; 
which  are  given  by  three  fundamental  equations  of  this  method  [5994(31,  32,  33)]. 

Table  II.  To  find  the  time  T  of  describing  a  parabolic  arc,  by  a  comet  ;  there  being  given  the  sum 
of  the  radii  r-\-r",  and  the  chord  c,  connecting  the  two  extreme  parts  of  the 
arc.     This  table  is  computed  by  Lambert's  formula  [750],  namely, 

7  =  9"'''^',  688724.   j  (,-  +  r"  +  c)^  — (r +  r"  — c)*  (  ; 

and  the  numbers  are  given  to  the  nearest  unit  in  the  third  decimal  place,  expressed  in 
days  and  parts  of  a  day.  This  degree  of  accuracy  being  abundantly  sufficient  for  the 
purpose  of  computing  the  orbit  of  a  comet,  by  Dr  Olbers's  method  ;  and  the  table  serves 
to  facilitate  this  part  of  the  calculation. 


CONTENTS   OF   THE    THIRD    VOLUME.  XXIX 

Table  III.  To  find  the  anomaly  U,  corresponding  to  the  time  t'  from  the  perihelion,  expressed  in 
days,  in  a  parabolic  orbit;  where  the  perilielion  distance  is  the  same  as  the  mean  distance 
of  the  earth  from  the  sun.     The  arguments  of  this  table,  as  they  were  first  arranged  by 

days  days 

Burckliardt,  are  the  values  of  r,  from  I'^O  ,0  to  t'  =  G  ,0;  and  the  logarithm 
of  t'  from  log.<'^0,700  to  log.  <'^5,00;  the  corresponding  anomalies  being  given 
from  17=0''  to  [/=  172''32"'09',9.  We  have  also  given  Carlini's  table  for  the 
first  six  days  of  the  value  of  t'.  This  last  table  has  for  its  argument  log.  of  t'  days  ; 
and  the  corresponding  numbers  represent    log.  U   in  minutes,  minus  log.  t'  in  days.        9S7 

Table  IV.  To  find  the  true  anomaly  v,  in  a  very  excentric  ellipsis  or  hyperbola,  from  the 
corresponding  anomaly  U  in  a  parabola;  according  to  the  method  of  Simpson, 
improved  by  Bessel.  This  table  contains  the  coefficients  of  Simpson's  correction, 
corresponding  to  the  first  power  of  (1 — e);  and  those  of  Bessel's  correction, 
corresponding  to  the  second  power  of  (1 — c)  ;  for  every  degree  of  anomaly  from 
0**   to    180'';   as  they  were  computed  by  Bessel 996 

Table  V.  This  table  was  computed  by  Gauss,  for  the  purpose  of  finding  the  true  anomaly  v, 
corresponding  to  the  time  t  from  the  perihelion,  in  a  very  excentric  ellipsis,  noticing 
all  the  powers  of   1  — e 999 

Table  VI.  This  table  is  similar  to  Table  V,  and  was  computed  by  Gauss  for  finding  the  true 
anomaly  r,  corresponding  to  the  time  t  from  the  perihelion,  in  a  hyperbolic  orbit, 
which  approaches  very  nearly  to  the  form  of  a  parabola;  noticing  all  the  powers 
of  (e— 1) 1002 

Table  VII.  This  was  computed  by  Burckhardt,  for  the  purpose  of  finding  the  time  t,  of  describing 
an  arc  of  a  parabolic  orbit  ;  there  being  given  the  radii  r,r',  and  the  described  arc 
v'—v  =  2f. 1005 

Table  VIII.  This  table  was  computed  by  Gauss,  and  is  used  with  Table  IX  or  Table  X,  in  finding 
the  elements  of  the  orbit  of  a  planet  or  comet,  when  there  are  given  the  two  radii  r,  r', 
the  included  heliocentric  arc  v'  —  x)  =  2/;  and  the  time  t'  —  t,  of  describing  this 
arc,  expressed  in  days.  . 1006 

Table  IX.     This  table  is  used  with  Table  VIII,  in  the  computation  of  an  elliptical  orbit,  by  means  of 

r,r',v' — V   and   t'  —  t 1012 

Table  X.      This  table  is  used  with  Table  VIII,  in  the  computation  of  a  hyperbolic  orbit,  by  means 

of  r,r',  v'  —  V,  and   t' — t 1013 

Table  XI.     To  convert  centesimal  degrees,  minutes  and  seconds,  into  sexagesimals.     .....     1014 

Table  XII.    To  convert  centesimal  seconds  into  sexagesimals,  and  the  contrary 1016 

The  Tables  V  —  X,  include  all  those  which  Gauss  published  in  his  Theoria  Molus,  etc.  We  have 
altered,  in  some  respects,  the  arrangement  and  forms  of  these  tables,  to  render  them  more  convenient 
for  use  ;  and  upon  comparison  it  will  be  found,  that  this  appendix  contains  the  most  important  of  the 
methods  which  are  given  in  that  great  work,  as  well  as  in  that  of  Dr  Olbers.  The  methods  of  Gauss 
being  somewhat  simplified,  by  reducing  many  of  the  processes  to  the  common  operations  of  spherical 
trigonometry,  instead  of  using  a  great  number  of  unusual  auxiliary  formulas,  expressed  in  an  analytical 
manner;   and  Olbers's  calculations  are  abridged  by  the  use  of  Tables  I,  II. 

VOL.    III.  ^ 


ERRATA. 


CORRECTIONS      AND      ADDITIONS 

IN  VOLUME  I. 

PagR.  Line. 

119  6  bot.  For  dw   read  dia. 

120  13, 19,  21  J'or  (zdx—xdy)  read  (zdx—xdz). 
125     12  For   dZ-j-dy,,   read  dZ-\-dz,. 

7  \)o\..  For — l.m.Sn.ds,  read  —Xj.m.Sv.ds. 
7  bot.  For  — y'ddx',    read    — yddx'. 
4  bot.  For     Y    read    y. 

3  bot.  Insert  dm  in  the  last  term. 

7  Insert    (    after  xK 
9  bot.  For  |.  read  4.. 

4  bot.  For  .2  read  ^. 
9  bot.  For  axis  of  z,  read  axis  of  x. 

16  For  dy  read  Sy. 

10  bot.  For  {dp)  read  (J-p). 

3  bet.  For  dr'  read  dr. 

4  bot.  For  ag  read  a,g. 

8  bot.  For  0-.U  read  au'. 

7         Change  tlie  accents  in  the  denominator  of  I'. 
1  bot.  For  /2a,  read  /2-2. 

7  bot.  For  2,   read  r2. 

12  For  shi.mt,  read  sin. ?nn<. 

13  For  cos.mt,  read  cos.mnt. 
3  For  sin.2»i<,   read  2.sin.2ji(. 

11  For  [6S8a],  read  [66Su]. 
1  For  sin.4.(t),— 6),  read  sin.4.(i',— 6). 

2  2 

10  bot.  For  — ,  read  — . 

r  *  r 

3  For  0",5,  read  0«,5. 
1,2 bot.  For  logarithm,  read  logarithmic. 

8  bot.  For  tang.(/g"— ;■),  tang.  {IS"'—j)  ;  read 
sin.(/3''— /),  sin  (/3"'— /). 

7  bot.  For  éy,  read  d'y'. 
6  For  c,  read  c'. 

4  For  y',y',  fcc,   read  y,y',  &c. 
IS  i^or  iy',)/',  &c.,  read  y,y',&.c. 

5  bot.  For  6'  reaa  j'. 

6  bot.  For  c=V',  read  c'=V'. 
4  liot.  For  .111,  read  Jl^D. 

8  bot.  For   [1034(;],  read   [1069a]. 
1  bot.  For  the  exponent  — è,  read  4. 


134 
147 
147 
147 
159 
182 
183 
209 
215 
220 
230 
234 
235 
280 
281 
301 
371 
371 
378 
378 
381 

398 
413 

455 
464 

475 

478 
480 
487 
495 
499 
542 
581 
585 


Page.  Line. 

593       5  bot.  for  [109Sa],  read  [10976']. 

608  Id  For  B,  read  B„. 

618  15  For  spherical  angle,  read  spherical  triangle. 

679       5  bot.  For  m'p,  read  m'p'  ;  and/br  m'q,  read  m'q'. 

693  4  bot.  For  m,  read  m'. 

715  15  bot.  For  andt,  read  an,  in  both  formulas. 


IN  VOLUME   II. 


370     16         For  [1581a],  read  [1851a]. 

510     11  bot.  For  >.    read  e. 

L'  ,  L- 

780       4  bot.  For    —  ,  read  —  . 

r'3  T.'-i 


781       5  bot.  For 


read  —- . 


IN    VOLUME  III. 


The  same  measures  have  been  used  for  .correcting  the 
mistakes  ol  the  press  in  Volume  III,  as  in  printing  the 
preceding  volumes.  The  reader  will  also  omit  the  third 
line  from  the  bottom  in  page  501,  which  is  unnecessarily 
repeated  ;  and  at  the  end  of  the  paragraph,  page  556,  line 
16,  will  make  the  following  addition  of  a  paragraph  which 
was  accidentally  omitted.  "  The  function  [5082s]  contains 
also  the  terms  depending  on  120m2..4(8),  120m2../î(9) 
[5261c,  e,  line  1],  which  are  derived  from  the  part 
— Ja.  funct.  [4931;)]  contained  in  [50825].  For  by  combining 
the  term  A&>  ee' .e.os.{cio-\-e'mv)  in  [493 J^,  col.  1]  with 
— |.e.sin.(2i) — 2nit!— cr),  in  col.  2,  we  get  the  first  of  these 
terms;  and  by  combining  the  term  .4(9).e£'.cos.(CB — c'mtj), 
with  — Je. sin. (2b — 2niii — ev),  in  col.  2,  we  get  the  second 
of  these  terms."  Lastly,  in  page  458,  line  3,  we  may  add, 
that  the  function    [4957]    must  be  multiplied  by  the  chief 


term  of  [4S90],  or 
[4961  or  4960e]. 


to  obtain  the  corresponding  terms  of 


SECOND  PART. 

PARTICULAR  THEORIES  OP  THE  MOTIONS  OF  THE  HEAVENLY  BODIES. 


SIXTH    BOOK. 

THEORY  OF  THE   PLANETARY  MOTIONS. 


The  motions  of  the  planets  are  sensibly  disturbed  by  their  mutual 
attractions,  and  it  is  important  to  determine  accurately  the  inequalities  which 
result  from  this  cause  ;  for  the  purposes  of  verifying  the  law  of  universal 
gravitation,  improving  the  accuracy  of  astronomical  tables,  and  discovering 
whether  any  cause,  foreign  from  the  planetary  system,  produces  a  change  in 
its  constitution  or  its  motions.  The  object  of  this  book  is  to  apply  to  the 
bodies  of  this  system,  the  methods  and  general  formula  given  in  the  first  part 
of  this  work.  We  have  developed  in  the  second  book,  only  those  inequalities 
which  are  independent  of  the  excentricities  or  inclinations  of  the  orbits,  and 
those  which  depend  upon  the  first  power  of  these  quantities.  But  it  is  often 
indispensable  to  extend  the  approximation  to  the  square  and  to  the  higher 
powers  of  these  elements  ;  and  sometimes  it  is  also  necessary  to  consider  the 
terms  depending  on  the  square  of  the  disturbmg  force.  We  shall  first  give 
the  formulas  relative  to  these  inequalities  ;  and  shall  then  substitute  in  these 
formulas,  and  in  those  of  the  second  book,  the  numbers  or  values  of  the 
elements  corresponding  to  each  planet.  By  this  means  we  shall  obtain 
the  numerical  expressions  of  the  radius  vector,  and  the  motions  of  the  ^jlanet  in 
longitude  and  in  latitude.  Bouvard  has  willingly  undertaken  the  calculation 
of  these  substitutions,  and  the  zeal  with  which  he  has  prosecuted  this 
laborious  work,  deserves  the  acknowledgment  of  all  astronomers.  Several 
mathematicians  had  previously  calculated  the  greater  part  of  the  planetary 
inequalities  ;  and  their  results  have  been  useful  in  verifying  those  of  Bouvard  ; 
for  when  any  difference  has  been  found,   he  has  examined  into  the  source  of 

VOL.  HI.  1 


PARTICULAR  THEORIES  OF  THE 

the  error,  in  order  to  satisfy  himself  of  the  accuracy  of  his  own  calculation. 
Lastly,  he  has  reviewed  with  particular  care,  the  calculation  of  those 
inequalities  which  had  not  been  before  computed  ;  and  by  means  of  several 
equations  of  condition,  which  obtain  between  these  inequalities,  I  have  been 
enabled  to  verify  many  of  them.  Notwithstanding  all  these  precautions, 
there  may  possibly  be  found  in  the  following  results,  some  errors,  which 
almost  inevitably  occur  in  such  long  calculations  ;  but  there  is  reason  to 
believe  that  they  amount  only  to  insensible  quantities,  and  that  they  cannot 
be  detrimental  to  the  general  accuracy  of  the  tables  founded  upon  them. 
These  results,  on  account  of  their  importance  in  the  planetary  astronomy, 
of  which  they  are  the  basis,  deserve  to  be  verified  with  the  same  care  that 
has  been  taken  in  the  calculation  of  the  tables  of  logarithms  and  of  sines. 

The  theories  of  Mercury,  Venus,  the  Earth,  and  Mars,  produce  only 
periodical  equations  of  small  moment  ;  they  are,  however,  very  sensible,  by 
modern  observations,  with  which  they  agree  in  a  remarkable  manner.  The 
development  of  the  secular  equations  of  the  planets  and  of  the  moon  will 
make  known  accurately  the  masses  of  these  bodies,  which  is  the  only  part 
of  their  theory  that  remains  yet  somewhat  imperfect.  It  is  chiefly  in  the 
motions  of  Jupiter  and  Saturn,  the  tAvo  greatest  bodies  of  the  planetary 
system,  that  the  mutual  attraction  of  the  planets  is  sensible.  Their  mean 
motions  are  nearly  commensurable  ;  so  that  five  times  that  of  Saturn  is 
nearly  equal  to  twice  that  of  Jupiter,  and  the  great  inequalities  in  the  motions 
of  these  two  bodies  arise  from  this  circumstance.  When  the  laws  and 
causes  of  these  motions  were  unknown,  they  seemed,  for  a  long  time,  to 
form  an  exception  to  the  law  of  universal  gravitation,  and  now  they  are  one 
of  the  most  striking  proofs  of  its  correctness.  It  is  extremely  curious  to  see 
with  what  precision  the  two  principal  equations  of  the  motions  of  these 
planets,  whose  period  includes  more  than  nine  hundred]  years,  satisfy  ancient 
and  modern  observations.  The  development  of  these  equations  in  future 
ages,  will  more  and  more  prove  this  agreement  of  the  theory  and  observation. 
To  facilitate  the  comparison  with  distant  observations,  we  have  carried  on 
the  approximation  to  terms  depending  on  the  square  of  the  disturbing  force, 
and  it  is  hoped  that  the  values  here  assigned  to  these  equations  will  vary  but 
very  little  from  those  found  by  a  long  series  of  observations  continued  during 
an  entire  period.  These  equations  have  a  great  influence  upon  the  secular 
variations  of  the  orbits  of  Jupiter  and  Saturn,  and  we  have  developed  the 
analytical  and  numerical  expressions  arising  from  this  source.     Lastly,  the 


MOTIONS  OF  THE  HEAVENLY  BODIES.  3 

planet  Uranus  is  subjected  to  sensible  inequalities,  which  we  have  determined, 
and  which  have  been  confirmed  by  observation. 

The  first  day  of  this  century  is  remarkable  for  the  discovery  of  a  new 
planet,  situated  between  the  orbits  of  Jupiter  and  Mars,*  and  to  which  the 
name  of  Ceres  has  been  given.  It  appears  as  a  star  of  the  eighth  or  ninth 
magnitude  ;  its  excessive  smallness  renders  its  action  insensible  on  the 
planetary  system  ;  but  it  must  suffer  considerable  perturbation  from  the 
attractions  of  the  other  planets,  particularly  Jupiter  and  Saturn,  which  ought 
to  be  ascertained.  It  is  what  we  propose  to  do  in  the  course  of  this  work, 
after  the  elements  of  the  orbit  have  been  determined  by  observation  to  a 
sufficient  degree  of  accuracy. 

It  is  hardly  three  centuries  since  Copernicus  first  introduced  into 
astronomical  tables  the  motion  of  the  planets  about  the  sun.  A  century 
afterwards,  Kepler  made  known  the  laws  of  the  elliptical  motion,  which  he 
had  discovered  by  observation  ;  and  from  these  laws,  Newton  was  led  to  the 
discovery  of  universal  gravitation.  Since  these  three  memorable  epochs  in 
the  history  of  the  sciences,  the  progress  of  the  infinitesimal  analysis  has 
enabled  us  to  submit  to  calculation  the  numerous  inequalities  of  the  planets 
depending  upon  their  reciprocal  action  ;  and  by  this  means  the  tables  have 
acquired  an  unexpected  degree  of  accuracy.  It  is  believed  that  the  following 
results  will  give  to  them  a  much  greater  degree  of  precision. 

*  (2341)    This  volume  was  published  by  the  author  shortly  after  the  discovery  of  Ceres, 
January  1,  ISOl  ;  and  before  the  discovery  of  the  planets  Pallas,  Juno,  and  Vesta.     He  did     [3698a] 
not  compute  the  numerical  values  of  the  perturbations  of  their  motions  as  he  had  intended. 


4  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 


rèr. 

Fi  ret  form. 


Radius. 


CHAPTER  I. 

FORMULAS  FOR  THE  INEQUALITIES  OF  THE  MOTIONS  OF  THE  PLANETS  WHICH 
DEPEND  UPON  THE  SQUARES  AND  HIGHER  POWERS  OF  THE  EXCENTRICITIES  AND 
INCLINATIONS  OF  THE  ORBITS. 


ON  THE   INEQUALITIES  WHICH  DEPEND  UPON  THE  SQUARES  AND   PRODUCTS  OF   THE 
EXCENTRICITIES  AND   INCLINATIONS. 

Differen  ^*    '^^  determine  these  inequalities,  we  shall  resume  the  formula  [926],^ 

tial  equa- 


[3699]  0  =  -jj^  +  -^  +  2fdR  +  r.(j-y 

We  have,  as  in  [605',  669], f 


[3700]  T  =  W^ 


[3701]  r  =  a.{l  +|e^  —  e  .  cos.  (nt-\-s  —  zi)  —  i el  cos.  2.  (n  ï  +  s  —  w)}  : 

hence  the  preceding  differential  equation  becomes,} 


Differeu-  tj^  rS 

tial  eijua-  -^  a    .  /  u 


;;^:,ir"  0=-^  +  n\r6r+3rî'a.ôr.{e.cos.(nt+i—z,)  +  eKcos.2.(nt+e—z=)l 

[3702]  "^  ^ 

sroo^nd  ^2fdR  +  r.C^ 

form.  -^  \ch- 


[3699a]         *  (2342)    Substituting,  in  [926],  the  value  of  r  R  [928'],  it  becomes  as  in  [3699]. 

r3700a]         ^  {2343)   The  equation  [3700]  is  easily  deduced  from  [605']  ;  and  the  value  of  r  [3701] 
is  the  same  as  that  in  [669],  neglecting  tenns  of  the  order  e^. 

f  (2344)    If  we  use,  for  brevity,  the  same  symbols  as  in  [1018a],  namely, 
[3702o]  T=nt~nt-Jf-s'—s,       W=nt+s—zi,       b  =  ie^—e.cos.W—ié^.cos.2W, 

[3703i]     we  shall  have   r=a.(l+è)  [3701];   hence    r-^=a-^.{l-\-b)-3=a-^.{l—3b-\-6b^); 
neglecting  6'  and  the  higher  powers  of  b  ;  or,  in  other  words,  neglecting  e^  e*,  8ic.    Now,  by 


VI.  i.  §1.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  7.  6 

Now  all  the  terms  of  the  expression  of  R,    depending  on  the  squares  and      [3702] 
products  of  the  excentricities  and  inclinations  of  the  orbits,  may  be  reduced    .j,^^^^^,. 
to  the  one  or  the  other  of  these  two  forms,*  dopSdin- 

on  anglea 

R  =  M.  cos.  { i .  (n'  t  —  nt  +  B'  —  s)-{-2nt-\-K\;  (Pi-t  form.j  [3703] 

of  two 


Rz=N.  cos.  { i .  {11!  t  —  n  i  +  s'  —  0  +  -^1  ;  f®'"™''  '■"'"■i  '^^'"■*] 

different 
forms. 

in  which  i  includes  all  integral  numbers,  positive  or  negative,  comprehending 

also   i  =  0  [954"].     JVe  shall,  in  the  first  place,  consider  the  term  [3703].      [3704'] 

It  produces,  in     2fàR-\-r.(^—\     the  function f  [3^04"] 

\  .^•^^~^);"    .  M-^a.(y^\  \  .  cos.  {i.(n't—nt+s'—{)+2nt+K\. 

\tn' -\-{2  —  t).n  '         \da  J  ),  *      ^  '  yi  1       4 


[3705] 


[3702c] 


retaining  ternis  of  the  order  e^,  we  get,  successively,  66^=6e^.cos.^fF=3e^-|-3e^.cos.2  W; 
hence  \  —  ^h-{-Qb^=l  +  ie^-\-2e.  cos.  W+  f  1  œs.  2  W.  Substituting  this  in  r'^ 
[.37026],  and  then  muhiplying  by  i^.rSr,  we  get  [3Î02(?]  ;  which  is  easily  reduced  to 
the  form  [3702e],  by  the  substitution  of  n^  [3700]  and  r^a.  (1  — e.cos.^  [3701]  in  the 
last  temi  of  the  second  member.  Now  we  have  — 3e^.cos.^  ?f  =  —  f  e^ — fe^.cos.2  fV; 
hence  [3702e]  becomes  as  in  [3702/], 

'~^  =  a3''^  ^  '''^a^'  '^  ^  ^  '  ^^  "^  '^  "^  ^  '  ^°^'  ^^+|fi^-C0S.2  TVl  [3702a;] 

=  71^.  rSr-\-n-.a5r.l<^e^+3e.  cos.  W-\-^e^.  cos.  2W\.\\  —  e.  cos.  W\  [3702e] 

=^n\r5r~\-n^.aSr  .\Qe. COS.  fF+ 3  e^.  cos.  2  W\.  [3702/] 
Substituting  this  in  [3699],  we  get  [3702]. 

*  (2345)  This  will  be  e^^dent  by  the  substitution  of  «,,  v,,  &,c.  [1009,669]  m  [957]. 
It  also  appears  from  [957"",  &c.]  ;  for  in  [3703],  the  coefficients  of  n'  t,  —nt,  are  i,  i-2,  [3704o] 
respectively  ;  their  difference  2  expresses  the  order  of  the  coefficient  k  [957'''',  &c.],  or 
that  of  M  [3703]  ;  which  must  therefore  be  of  the  order  2  or  e^.  In  like  manner,  the 
coefficients  of  ?i'  t,  —  n  t  [3704]  being  both  equal  to  i  ;  the  coefficient  JV  may  contain 
terms  of  the  orders  0,  2,  4,  he.  [957"'S  &;c.],  which  include  those  of  the  order  e^  ;  and  [3704i] 
a  very  little  attention  to  the  remarks  in  [957^,  &tc.]  will  show,  that  these  are  the  only  forms 
of  this  kind  containing  e^. 

t  (2346)     Substituting  the  expression      r  .(——j=a.( — J    [962],    in   the  function     [3705a] 

[3704"],  we  get     2/dfl  +  7- .  (^^)  =:2/di?+ a.  ('^V      In  finding    d  R,    we  must     [37056] 

suppose,  as  in  [916'],  the  ordinaies  of  the  body  m  to  he  the  only  variable  quantities;  or,  in  other 
words,  we  must  consider  nt  as  variable,  and  n't  cojwton^,  as  is  done  in  finding  d/î  [1012a — c]. 
Now  in  taking  for  R  the  form   [3703] ,      R—M.  cos.  { i .  (w' t — nt-}-s' —  i)J^2nt-\-Kl,     [3705cl 
VOL.   HI.  2 


6  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

We  have  seen,  in  the  second  book  [1016],  that  the  parts  of     —      depending 

on  the  angles      i.(n't  —  nt  +  e' — e)      and      i.(n't  —  nt-\-s — 5)  +  ni  +  £, 
°'^""  °      are  of  the  following  forms, 

[3706]        —  =F.cos.i.(n't — nt+e' — e)-^eG.cos.{i.(n't — 7it-\-s — s)-{-nt+e — ^  \ 

depending  " 

o?Z'fiT..  -te'H.cos.{i.(n't—7it+i'—^)  +  nt+B—z>'\; 

hence  the  function 

[3707]  3n^.a&r.\e.  cos.  (7it  +  e  —  ra)  +  e\  cos.  (2 n i  +  2 s  —  2  w) } 

will  produce,  in  [3702],  the  following  terms,* 

C{F+G).e\cos.{i.(7i't  —  nt  +  s'—i)  +  2nt  +  2s—2^]       } 
[3708]  |»-«-.^      -^H.€e'.cos.{i.(7i't—nt  +  e'—B)  +  2nt  +  2^—^—^'\l' 

Therefore,  if  we  notice  only  the  terms  depending  on  the  angle 

i.(n't  —  7it  +  s—s)  +  27it, 

[3709]      and  put    (x  =  1  ;    which  is  equivalent  to  the  siipposition  that  the  sim^s  mass  is 
[3709']     equal  to  tmity,  7ieglecting  the  mass  of  the  planet  ;  f  7ve  shall  have     n^  «^  =  1  ; 


[3705d]     we  obtain  d  R  =  — {2  — i)  .n.  M .sm.  {i.  {n't  —  7it  -Jf-  I'—s)  +  2  7it  -{- Kl-ctL Integrating 
this,  and  multiplying  by  2,  we  get 

[3705e]  2fàR=  .^,f~'':"    .M.cos.{i  .  {n't-nt  +  ^-i)  +2n  t  ^K\. 

The  partial  differential  of   R  [3705c],  relative  to  a,  being  multiplied  by  a,  gives 

[3W]  a.Ç^)  =  a.{'^).cos.ii.in't-r,t  +  s-s)+2nt  +  K}. 

Adding  this  to  the  expression  [3705e],  we  get     2/d  R-\-a  .  (j^j  r     as  in  [3705]. 

*  (2347)     The  forms  of  the  temis  of    -,     assumed  in  [3706],  are  the  same  as  those 

computed    in    [lOlG]  ;    the    constant    part    corresponding  to     i  =  0;      and    the    secular 
[3708a]     teiTOS  being  made  to  disappear,  as  in  [1036",  &c.].        Substituting  these  in  [3707],  and 
reducmg    by    formula    [20]    Int.,    retaining    only   the    teims    dependmg    on    the    angle 
i .  („'  t  —  nt  +  s'—s)-\-2nt  +  K  [3703],  we  get  [3708]. 

t  (2348)    M  being  the  mass  of  the  sun,  and  m  that  of  the  planet,  we  have    JU+m^M- 
[3709a]     [914'].     If  we  put  Jkf=l,  and  neglect  m  on  account  of  its  smalhiess,  we  shall  have  fA=l  ; 
and  then  fiom  [3700],  we  shall  get  [3709']. 


VI.  i.  §1.]  TER]\IS  OF  THE  SECOND  ORDER  IN  e,  e',  y. 

and  then  the  differential  equation  [3702]  will  become* 

^      rf2.(,6,)  ^i{F+G).c\cos.\i.{n'l-nt^s'-z)+2nt  +  2s-2v>\\ 

</«2  -  ^      -\-H.ee'.co5.\i.{r^t—nt^^—s)-\-2nt^1i-zs-vi'\) 

(i)i+(2 — i).n  \(/o/) 

Hence  we  get,  by  integration,! 

^   (  (F+G).Ê2.cos.^ù(n'<  — w<  +  £'— 5)+2ji<  +  2s  — 2-nf 

A  «".  <  >  I  Values  of 

(       +H.ee'.cos.  fi.(ji'i  — n<+E' — s)  +  2?i  <+2  s  — «—• n'}  )>        f  ^(îr 

V      J      depending 


[3710] 


rSr 


(in'-\- (2 — i) .n  \da  J  '^ 


on  angles 
of  the  first 
form. 

[3711] 


a2  {i.n'+(3  — i).Mf  .{!'n'+(l  — «).n| 

TOT 

If   this    expression    of      be    considerable,    and    one    of   its    divisors 

i  n'  +  (3  —  i)  .n,     i  n'  -\-  (\  —  i)  .  n,     be  very  small,  as  is  the  case  in  the 
tlieory  of  Jupiter,  disturbed  by  Saturn,  when  we  suppose    i  =  5  ;    2n  being      [3712] 
nearly  equal   to    5n'  ;%   the  variableness  of  the   elements  of  the  orbit  will 


*  (2349)    Substituting,  in  [3702],  the  value  of  its  third  and  fourth  terms  [3708],  also 
the  values  of  the  fifth   and  sixth  terms  [3705],  multiplied  by   n^  a^  =  1 ,    for  the  sake  of    [3710a] 
homogeneity;  it  becomes  as  in   [3710]. 


[3711a] 


t  (2350)    If  we  put,  in  [865,  870'],     y=rSr,     a  =  n,     a  Q  =  2  .a/f.™- (m,^  +  6,), 

the  letters  m,  s  bemg  accented  to  prevent  confusion  in  the  notation,  and  2  denoting  the  sign 
of  finite  integrals;  we  shall  have  the  differential  equation  [3711&],  whose  integral  [871] 
is  as  in  [3711c], 

r  5  r  =  2  .  -4^, .  f^-  (m  t  +  s)=     "- ^     .  [3711c] 

m^a_„a    cos.  ^    '     i     i'        m,^—n^  ^ 

Comparing  the  coefficient  of  <  in  the  expressions  [3710,  37116],  we  get  OT,=i.  (w'— M)  +  2n;  [3711d] 
hence  m,^ — n-z={m,-{-n)  .{m^ — ?i)=  ^fn'_[-(3  —  i).n\  .\in'-\-{l — i).n\;  substituting  [3711e] 
this  in  [3711c],  and  then  dividmg  by  a^,  we  get  [3711]. 

t  (2351)    We  have,  in  [4077],  for  Saturn    n'=43997'';    and  for  Jupiter    m=109256'    r37n/-n 
nearly;    hence    5?i' — 2  n  =  1473^;    which  is  quite  small  in  comparison  with    n   or    n', 
being  only  y\  part  of  n. 


8  PERTURBATIONS  OF  THE  PLANETS. 

have  a  sensible  influence  on  this  expression  ;  it  is  important,  therefore,  to 
notice  this  circumstance.  For  this  purpose  we  shall  put  the  differential 
equation  [37 1 0]  under  the  following  form,* 

0=  ^^^^-\-n-.rôr-\-7i-a^P.cos.{i.(n't  —  nt-\-s'—i)-{-2nt  +  2s\ 
[3713]  dt^  '      ^  /    I  I        3 

+  n'a^F.  s'm.\i.  (n't  —  nt  +  b'—b)  J^2nt  +  2s\. 

Integrating  this,  and  neglecting  the  terms  depending  on  the  second  and 
higher  differentials  of    P,  P',    we  shall  obtain  f 

r  7i" 


^aTulof  a^  {i7i'~\-  (3  —  i)  .  71] .  [ill'  -\-{l  —  i)  .  ii] 

noticing  /  C  _  \      d  P' 

the  secu-  «/-.-.  .    .    „ 

lar  varia- 
tion of  the  _ 

elements.  S  /  '     \in'-\-[^-i).nl  .  iin'-\-{l—i).n\ 

[3714]        x<  ^  >      i    i      -ry         >     )  .  v.(B) 

+  \  p-       2.^KK-„)+2n|.—       /  ^.^  ^iÇn't-nt+s'-s)+2nt+2-:}  ] 

[371%]  *  (2352)    If  we   put,  for  brevîty,       T,=  i  .  {n't —  nt -\- i' —  s) -\-2n  t -\-2s,      the 

term  depending  on    J*',    in  [3710],  mil  become 

[3711^]  3  „3  «2  2^  e^.  COS.  (  T;  —  2  in)  =  f  «2  «a  Fe^.  {cos.  T, .  cos.  2  «  +  sin.  T, .  sin.  2  ra |  ; 

[3711i]  if^veput  |Fe2.cos.2zj=P;  |Fe8,sb.2a=P',  it  becomes  mV. {P. cos. T+P'. sin.  TJ, 
as  in  [3713].  In  like  manner,  the  terms  of  [3710],  depending  on  G,  H,  M,  maybe 
reduced  to  the  forms   [371  li]  ;  P,  P'  being  functions  of  the  variable  elements  e,  ra,  Sic, 

■■  ^     and    r,  T'   mdependent  of  these  variable  elements  ;  observing,  that   n,  a,  s  [1045',  1044"] 

are  considered  as  constant,  as  well  as  the  similar  elements  of  the  planet  m'. 

■f  (2353)    Using  the  abridged  symbols    m,.  T,  [3711(Z,  g],  and  substitutmg,  in  [37116], 
r3714o]     tlie   flmction   [3711/],    instead  of  the  temis   under  the  sign    2,    this   differential  equation 
becomes  of  the  form  [37146],  and  the  integral  [3711c],  taken  in  the  hypothesis  that  P,  P' 
are  constant,  becomes  as  in  [3714  c], 

[3714i]  0  =  ^l^Sdll  j^n^,rôr  +  rv"  é.  {P.  cos.  T,+  P'.  sin.  T,\  ; 

712  a2. 1  p.  COS.  r, +P'.  sin,  rj 

[3714c]  r  5  r  = . 

«1,2  —  rfi 

We  shall   suppose    r  &  r,   to  be  increased  by  the  quantity    [r  (5  r] ,    in  consequence  of  the 
secular  variation  of  P,  F,   so  that  mstead  of  [3714c],  we  shall  have,  generally, 

[3714d]  ràr= ^^^^^^^ +['•5'-]. 


VI.  i.  §1.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  9 

The  formula  [931]  becomes,  by  putting    (^  =  1,* 

—  —  î>  •  S  i         \  Values  of 

a^ndt         -    ^       j^H.ee'.\i.{n't  —  nt-Jfi'—s)-^2nt-Jr2e—a—zi'l)      [  Sv 

1[^)  depending 
on  angles 
of  the  first 

è  V  = ;  [3715] 

V/l  — e2 

and  by  giving  to  i  all  positive  and  negative  values,  including  zero  [3704'],      [3715'] 
we  shall  obtain  all  the  inequalities,  in  which  the  coefficient  of  n  t    differs 
from  that  of    n't    by  two. 


Now  as  the  value  of  r  5  r  [37 1 4  c]  satisfies  the  equation  [3714J],  supposing  P,P'  to  be  constant, 

and  by  hypothesis  the  value  [3714(Z]  satisfies  the  same  equation   [37146],  when   P,  P'  aie     [37Ud'] 

variable  by  reason  of  the  secular  inequalities,  we  may  substitute   [3714d!]  in  [37 14 J],  and 

then,  from  the  resulting  expression  subtract  the  equation  [37146],  and  we  shall  obtain  an 

equation  of  the  form  [3714/],  observing,  that  we  must  retain  only  the  terms  depending  on  the 

first  and  second  differentials  of  P,  F,  namely,  dP,  dP',  d^P,  d^P',  to  the  exclusion  of  P,  F,      [3714e] 

^        d^.{ràr]  o    r     t    n    I      "a    ^^.f  p.cos.  r,  +  P'.sin.rJ 

0=-^^  +  n-.  ir&r-]+n~a^ (,„.-n^).rf<a ^^714/] 

Now  we  have,  generally,    d^.{P.co%.T)^d^P,cos.  T,+  2dP.d.{cos.T,)  +  Pd^.{cos.Ty,     [37Ug] 
in  wliich  the  term  containing    P  is  to  be  rejected  [3714e]  ;    and  if  we  neglect  the  term 
depending  on    d^P,   on  account  of  its  smallness,  we  shall  obtain 

d^.  {P .  COS.  T,)=2dP.d.  cos.  r,=  —  2dP.m^dt.  sin.  T,     [371 1<Z,  g].  [^W] 

In  like  manner  we  have 

d^.  (F.  sin.  T,)=2d F.  d  .  sin.  T,=     2dF.m,dt.  cos.  T, ;  [3714A] 

hence  [3714/]  becomes 

0  =  ^^^  +  n^[r<5r]  +  -^--^.j2m,.— .cos.T,-2m,.-.sm.r,|.         [3714.] 

This  is  similar  to  the  equation  [37116],  changing  rSr  into  [riîr],  representing  by  aQ 
the  tenns  depending  on  d  P',  d  P.  These  ternis  being  divided  by  m^  —  n^,  give, 
as  in  [3711c],  the  following  value  of   [?•  5  r]  ; 

r-j,.-!  S     ^"^       iZ    cos  T-     ^"'-       —    sb  t\  [37144] 

Substituting  this  in  [3714f/],  connecting  together  the  terms  depending  on  cos.  T^,  also 
those  depending  on  sin.  T,,  then  substituting  the  value  of  m^ — n^  [3711c],  and  dividing 
by   a^,   we  get  [3714]. 

*  (2354)     We    have       2  r  .  d5r -{- dr  .  ar  =  2  d  .{r^r)  — dr  .  5  r,        as    is    easily     [3715a] 
proved  by  developing  the  first  temi  of  the  second  member,  and  reducing.      Substitutmg 
VOL.   III.  3 


10  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

If  the  coefficient     in'-\-(2 — i).n     be  very  small,   and  this  inequality 

be    very    sensible,    as    is    the    case    in    the    theory    of    Uranus,    disturbed 

[3715"]    by    Saturn    [4527];    we    must   put    the    part    of     R     depending    on    the 

this  and  [3705a]  in  [931],  we  obtain 

^ -\-  I  \  3  a  In  at  .  dli  4-2  an  at  .  a  .  I  —    } 


[37156]  <J  w  =  ■ 


/(l-e^) 


The  differential  of  [3701],  being;  multiplied  by :; — — ,      becomes 

■-  a-ndt 

[3715c]  —  ^î^  "=  ~  TT  •  ^^  •  ^'"'  («  ^  +^  — «)  +  «■•  S'n-2  .  (n  <  +-=  — a)^ 

This  is  to  be  reduced,  as  in  [370Sn],  by  substituting  the  value  of    —    [3706],  using  tlie 

fonnula  [IS]  Int.,  and  retaining  only  the   terms   depending  on    the  angle     T,   [371l£-]  ; 
hence  we  get 

[3715rf]  -J^  =  -^(F+G).e^.sin.(T-2«)-iifee'.sin.(T-.-.'). 

[3715e]  Again,  if  we  put,  for  brevity.  To  =  i .  {n't—  n  t  +  /—  e)  +  2  n(  -\-K,  tlie  term  of  R  [3703] 
will  become     R  =  M.cos.T^;    hence  the  differential    à  R,    found  as  in  [916'],  upon  the 

[3715/]  supposition  that  nt  is  the  variable  quantity,  is  dR  =  — (2  —  i)  .n  d  t  .  M  .sm.  T^i- 
Multiplying  this  by    3  a.ndt,    integrating  and  using  m,  [37 lid],  we  get 


oafndt.dR  =  - .  a  M.cos.  T„  . 


[3715g] 


To  this  we  must  add     2andt  .a.  (-j—j  =  2andt  .a  .  (-j—j  •  cos.  T!,  ;      and    then,    by 
integrating  the  sum,  we  obtain 

[3715/.]  f[saJndt.dR  +  2andt.a.(^-^)]=\^^^^.aM+^Z^l^^ 

Substituting  this  and  [o715£Z],  in  [3715i],  we  get   [371.5]. 


[3715i] 


In  the  great  inequalities  of  Jupiter  and  Saturn,  the  most  important  parts  of  Sv,  Hv' 
[37 15 J,  &c.]  are  those  depending  on  the  double  integration  of  AR,  d!RI,  which 
introduces  the  divisor  (5  m' — 2n)2.  These  paits  are  to  be  applied  to  the  mean  motions 
[3715fc]  of  the  planets,  as  is  shown  in  [1066",  1070"].  As  we  must  frequently  refer  to  these 
parts  6v,  5v',  of  the  mean  motions  <^,  ^'  of  the  planets  m,  m',  we  shall  here  give  their 
values,  deduced  from  [1183,  1204,  3709a],  or  from  the  appendix  [5794],  representing 
the  chief  parts  of  &  v,  5v'  [37156,  Sic.]  ; 

[3715Z]  Sv   deduced  from  ^  =  3a  n  .fd  t  .fd  R  ; 

[3n5m]  (5  v'  deduced  from  ^'  =  3  a'  n'.fd  i  ./d'  R. 


VI.  i.  §1.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  11 


angle    i.(n't — nt-\-s  —  s  )  +  2  ?i  ^  +  2  s    [3703] ,    under  the  following  form,* 
R=       Q.cos.  {i .  (n'  t  —  nt  +  s'  —  s)  +  2nt  +  2sl 
+  Q'.  sin.  [i .  (n'  t —  nt  +  s' —  s) -^27it +  2sy^ 
and  we  shall  have,t 


[3716] 


(6— 3i).«2a     {  ^--rr     }  ,     ^  ,^ 

la.ffndt.àR^- ji-  I  q  +  .  ,,     ''^       >  .sin.  \i.{>i't-nt+s-s)J^2nt+2 

•'-'  \in'+{2-i).n\^   I       ^  in'-\-{2-î).n) 


[3717] 


(6-3»).n  a_^  )  Q'___HL_  }  .cos.{;.(M7-n<+s'-£)4-2n<+2s}. 


{in'+(2— i).nP    /  ni'+(2- 


*  (-2355)    Using,   for  brevity,     K,=  K — 2  s,     and     T,    [.3711^],    the    expression    of     [3716a] 
R  [3703]  becomes     iî  =  JIf  .cos.  (T,+Ar)=JM.cos./i:;.cos.2'— ^f .  sin.  Z;.sin.T,  ;    and 
by  putting    ^I.cos.Z,=::Q,   —  J/.sin.Z,=  Q';   it  changes  into    il=.Q.cos.r,4-Q'.sin.T,     [37166] 
as  in  [3716]  ;   Q,    Q'  bemg  like  P,  P'  [3711À;],  functions  of  the  variable  elements  of  the 
orbits,  and   T,  independent  of  them.       Now  we  have,  in  [4077],  for  Uranus  n  =  15425*'; 
for  Saturn    n'=: 43997''  nearly;    hence    3m  —  ?i'=2278»';  which  is  much  smaller  than  n     [3716c] 
or  n';    and  by  putting     i^^  —  1,    in  the   divisor    in' -{-{2 — i).n,    it  becomes    3m — n';    [3716(/] 
therefore  this  small  divisor  must  occur  in  computing  the  perturbations  of  Uranus  by  Saturn, 
as  is  observed  in  [3715'']. 

t  (23.56)    The  difierential   d  R,  deduced  from  [.3716i],  considering   nt    as  the  variable 
quantity,  as  in  [3715/],  is 

dR  =  —  {2  —  i).7idt.q.  sin.  T,  +  (2  —  i)  .ndt.q'.  cos.  T,  ;  [3717a] 

hence  we  have 

3  a  .ffn  dt.d  R=ffa  n^.di^.l{—6  +  3i).q.sm.  T,-{-  (6—3  î).q.  cos.  TJ.  [37174] 

If  the  integral  of  the  second  member  of  this  expression  be  taken,  supposing  Q,  Q'  to  be 
constant,  it  ^\^ll  produce  the  terms  independent  of  d(^,  c?  Q'  in  [3717].  The  terms 
depending  on  d(^,  d(^  may  be  estimated  by  means  of  the  general  formula  [1209è], 
which,  by  changing  ^,  B  into  Q,  A,  respectively,  and  neglecting  d^Q,  rf^Q,  Sic,  becomes 

ffAqdt^=qffAdt^-2.'^.fffAdt\  [3717c] 

From  this  formula,  it  appears,  that  the  term  depending  on  —,  is  easily  deduced  from 
that  depending  on    Q ,  by  changing   Q  into     —  2  .—^.dt,    and  then  integrating  relatively 

to    t,   supposing      —     to  be  constant.      In  this  way  we  easily  deduce  the  term  depending    [3717*^] 

on  dq  [.3717]  from  that  of  q-,  and  in  like  manner  we  get  the  term  depending  on  rfQ' 
from  that  of    q. 


12  PERTURBATIONS  OF  THE  PLANETS.       [Méc.  Cél. 

Hence  the  formula  [37156]  will  give* 

2d.{r5r)  UF-\-G).e^.smAi.(n't-7it4-s'-s)4-2nt  +  2s-2ôil       ) 

a^ndt  -     (       -\-H.ee'.sm.li.{n't—nt-\-e'—=)~{-2iii-\-2s—ss—zi']) 


bein;_ 
variable. 


[3719] 


^  fin'-\-{2-i).n\^'  [_"  ^'' in'-\-(2-î).nJ       in'-lf-[2—i).n 


-^{rr—, ~\  «QH — + }.sm.ii.{n't-nt+s'~i)+2nt  +  0g\ 


Another 
form  of  tins 
value  of 
ÔV, 

[3718] 


[3718']  For  greater  accuracy,  we  have  neglected  the  divisor  \/i — e^  in  this 
expression  of  (5ï?  ;  because  it  does  not  affect  the  part  of  this  expression 
which  has  the  square  of  mi' +(2 — i)  .  n  for  a  divisor,  as  we  have  seen 
in  [1197];  and  in  the  present  case,  this  part  is  much  greater  than  the 
others.      Moreover,  we  must,  as  in  [1197"",  1066",  1070"],  apply  this  part 

[3719']     of    &v    to  the  mean  motion  of   mf  ;    and  as  it  is  very  nearly  equal  to  the 

*  (2357)  Using  the  value  of  R  [3716],  or  rather  [37166,3711^];  taking  its  partial 
differential,  relatively  to  «,  which  will  aflect  only  Q,  (^' ;  multiplying  by  2a^.ndt,  and 
then  integrating,  we  get 

[d/lBaj  2  and  t .  a.  I  ——    = -r-    ■  sin.  1 , .    - —    .  cos.  i  ; 

■^  \da  /  m,        \da  J  '  m,        \da  J  ' 

m^  being,  as  in  [3711f/].  Substituting  this  in  [3715J],  also  the  values  of  the  terms 
[3717,  3715rf],  it  becomes  as  m  [3718]  ;  except  that  the  divisor  \/(l  —  c^)  is  neglected, 
[37186]  for  the  reason  mentioned  in  [3718'],  namely,  that  the  chief  part  of  Sv  or  ^  [1195  or  1197] 
does  not  contain  this  divisor  ;  and  as  the  other  terms  are  very  small,  it  may  also  be 
neglected  in  them. 

t  (2353)  The  tenns  of  Sv  [3718],  having  for  divisor  the  square  of  j'w'-f- (2  —  i)  ■  n, 
[3719a]  are  those  depending  on  3  affndt  .dR,  computed  in  [3717];  and  it  is  evident,  that 
this  part  of  S  v  much  exceeds  the  other  parts  depending  on  F,  G,  H,  he.  Now, 
by  [1066",  1070"],  or  by  [1197>'"],  the  parts  depending  on  3affndt.dR,  must  be 
applied  to  the  mean  motion,  and  as  the  other  parts,  depending  on  the  same  angle,  are  much 
[37196]  smaller,  we  may  suppose  that  the  whole  of  this  equation  is  to  be  applied  to  the  mean 
motion,  as  in  [3720].  We  may  remark  incidentally,  that  the  expression  of  r  [1066],  as 
well  as  that  of  v  [1070],  contains  the  double  integral  ffndt.dR;  hence,  at  the  first 
view,  it  would  seem  that  if  v  contain  terms  depending  on  this  double  integral  with  the  small 
divisor  [in' -{-{2  —  ?') .  «P,  as  in  [3718],  ?•  would  contain  similar  terms  of  the  same 
order.       But  we   must  observe,   that  these    terms  of    r,  v   [1066,  1070]   are  multiplied, 

[3719c]     respectively,  by     (  — — -  ) ,     f  — —  ) ,     or  by  their  equivalent  values    a  e  .  sin.  (n  i  -}-  s  —  a), 

l-t-2  e.cos.  (n< -|- s  —  «)    [669].      Hence  these  terms  of   v   will  be  multiplied   by   I, 


VI.  i.  §1.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  13 

whole  term  depending  on   the   angle      i.{n't  —  nt-\-i'  —  t)  -\-2nt  -^-2^, 

ive  may  apply  this  tvhole  inequality  to  the  mean  motion  of  m.  [3720] 

TIT         1.    11       1,      •  1  1  r        dP         iJP'         (JO         dO' 

We  shall  obtani  the  values  of      — — ,    — — ,     — -^,    —-i^,     by  takmg  the 

(It  (It  ^       dt  dt  •'  ^ 

differentials  of  the  expressions  P,  P',  Q,  Q',  relative  to  the  excentricities 
and  inclinations  of  the  orbits,  the  positions  of  their  perihelia  and  nodes,  and 
then  substituting  the  values  of  the  differentials  of  these  quantities.      But  we 

may  obtain  these  values  of     — — ,  &c.     more  simply  in  the  following  manner.       [3721] 

Find  the  value  of  P,  for  an  epoch  which  is  distant  by  two  hundred  years 
from  the  epoch  taken  for  the  origin  of  the  time  t  ;  then  putting  P^  for  this 
value,  and    T   for  the  interval  of  two  hundred  years,  we  shall  have* 

Formula 
,  ^  for  the 

yj^      d  ±  J-.  j->  détermina- 

1  .  j-^i'—f.  [3723] 

"   '  tion  of 

dP,  dP', 

T     .  £  J    1       1        c    dP"     do     dq  &c. 

In  the  same  manner,  we  may  nnd  the  values  oi      — — ,     — -^,     — -^. 

•^  dt  dt  dt 

or  TÔT 

To  deduce  the  expression  of     —     from  that  of     — j-,     we  shall  denote 

by    -^,    the  part  of    —   depending  on  the  angle  i.{n't—nt-\-i  —  6)+2ni+2s,      [3724] 

and  we  shall  havef 

ràr r     S^ — \-F.cos.i.{n't  —  nt-\-s  —  s)-{-Ge.cos.\i.{nt—nt-\-^—s)-\-nt-\-s  —  ra\  ( 

5"  —  „  '  S   '^  C  '       [3/25] 


[3722] 


+  i/e'.  COS.  ^i .  {in—nt-\-  s'— ;)  -\-nt-\-  s — jj'J 


S 


and  those  of  r  by  the  small  quantity  e,  which  will  make  it  of  a  less  order  ;  it  will  also  be  of    [3719rf] 
a  different  form  from  those  contained  in  this  article,  by  reason  of  the  factor    sin.(n<-|-£— ra). 

dP  (PP 

*  (2359)    From  Taylor's  theorem  [617],  we  have     P,=P  +  T.-— +|  T^.  — +  &c.; 

and  if  we  neglect  the  square  and  higher  powers  of   T,   on  account  of  the  smallness  of  the     [3723a] 
terms,  it  becomes  as  in  [3723]. 


t  (2360)    Adding     —     to  the  part  of    —    [3706],    we  shall  obtain  all  the  terms  of 


a  'a 

depending  upon  the   angles      i  .  [n' t  —  nt-\-i' — i),      i.{n't  —  nt-\-i' — s)  -^nt-\-i,     [3725o] 

i.{n't  —  nt-\-  s' —  s)  -{-  2  n  t  +  2  !.      Multiplying  this  by    - ,     we  get  [3725]. 

VOL.   III.  4 


14 


PERTURBATIONS  OF  THE  PLANETS. 


[Méc.  Cél. 


Value  of 

f),  r, 
[3736] 

for  the 
angles  of 
the  first 
form. 


[3726'] 


[3727] 

Computa- 
tion for 
angles  of 
the  second 
form. 


Hence  we  deduce* 

-^  =  ^+i.(i^+2G).e-.cos.{?:.(n'i  —  »/  +  /— 0  +  2/1^  +  2;— 2^J  > 
+  lH.ee'.cos.li.(n't—nt-Jrs—i)  +  2nt  +  2i  —  z:  —  -/\  ) 

2.  JVe  shall  compute,  in  the  same  manner,  the  terms  depending  on  the 
angle  i.Çn't  —  nt-\-s' — e)  ;  and  shall  suppose,  that,  by  carrying  on  the 
approximation  to  the  first  power  only  of  the  excentricities,  we  shall  havef 

—  =  F.cos.i.(7i't—nt-\-s—i)-\-Ge.cos.\i.(7i't — nt  +  s  —  !)  +  nt  +  s — ^J 
+  G'e  .cos.j — i.(7i't — nt^s' — £)  +  nf-(-£ — to  j 
+  iïe'.cos.|      i.(n't—nt+s'—s)-}-nt  +  s—^'\ 
-{'H'e'.cos.\—i.(n't—nt  +  s—s)-J^nt  +  i—^'\  ; 


[3726a] 

[37261] 
[3726c] 

[3726d] 

[3726e] 
[3726/] 

[3726g] 
[3726;i] 


*  (2361)  Using  the  symbols  [3702«],  namely,  T=n't  —  nt-\-e'—s,  TF=znt-\-s—a, 
W':=  n't-{-s' — zs',  the  expressions  [3725]  will  give,  by  transposing  the  terms  depending 
on    F,    G,  H  ;  f,..n,^  ca,,-~w^-^/yiXr+  V--UT' 

.F.cos.iT—-.Ge.cos.{iT+W)  — -.  He',  cos.  (i  T-j-  W/)  ; 


r     (5,  )■ 
a  '   a 


rSr 


and  from  [3701]  we  get     -  .  :^  1  -)-  4  «^ —  ^  •  cos.  W —  |  e^.  cos.  2  TV;     which  is  to  be 

substituted  in  [372Gè].  In  making  this  substitution,  we  have,  by  hypothesis,  only  to  notice 
terms  of  the  order    c^,  ee',  e'^,  &,c.  [3702',  &c.],  and  of  the  same  form  as  [3703].      Now 

(W*  .  /* 

the  term    -^    [3724]  being  already  of  the  second  order,  we  may  substitute  for  the  factor    - , 

by  which  it  is  multiplied,  the  first  term  of  its  value  [3726c],  namely  1  ;  in  the  coefficient 
of  -F,  we  may  use  the  term  —  i  e^.  cos.  2  TV  ;  and  in  the  coefficients  of  G,  H,  the 
term  — c .  cos.  TF ;  by  this  means  it  will  become  as  in  [3726^].  Reducing  this 
expression  by  means  of  [20]  Int.,  and  retaining  only  terms  of  the  form  [3703],  it  becomes 
as  in  [3726A],  which  is  of  the  same  form  as  in  [3726]. 

S^^rjr^      e^  cos.  2  TV) .  F.  cos.  iT-\-(e.  cos.  TV)  .Ge.  cos.  (i  T+TV) 


rSr 


+  {e.cos.TV).He'.cos.{iT~\-  TV,') 


=  -^+  IFe^.cos.  {i  T+2?F)  +  JGe^.cos.  {i  r+2fr)  -(-iffee'.cos.  {i  T+TV+T¥/). 


■j-  (2362)    The  expression  of      —   [3727]  is  the  same  as  [3706],  making  the  alteration 

required   by   the    supposition,    that    i    is   positive    [3727'].       If  we  use,    for  brevity,    the 
symbols  [3726a],  this  formula  will  become 


[3727a] 

[37276]     —  =F.  cos.i  T-\-Ge.  cos.(i  T-\-lV)+G'e-cos.(-i  T+W)+He'.  cos.  (i  T+  W/)+H'e'.  cos.(-  i  T-\-  W/). 


5r 


The  case  of    i^O,     is  separately  considered  in  [3755'",  Sjc.]. 


VI.  i.  §2.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  15 

i  being  positive  [3727rt,  6].     We  shall  then  get*  [3727] 

r  (  G'+  G') .  e2.  COS.  i .  {n'  t  —  nt  +  B'  —  e)  ^ 


+  He  c' .  COS.  { i .  {n't  —  nt^  s' —  s)  +  -. 


(E) 


[3728] 


r  0  r 


<        -\-  jn  ee  .  cos.  ^i.yn  i  —  ni  -^  s  —  jj  -j-  a  —  -n  5  > 

(      +H'ee'.cos.^;.(«'<-n?  +  6'— £)  — a  +  a'^)  ,    ,       ^_^^_^^^^ 


*  (2363)    In  finding  the  pai-t  of  rSr  dependmg  on  the  angle    i.{n't — nt-{-s'—i),  or  iT, 

by  means  of  the  fomiula  [3702],  it  is  necessary  to  compute  the  part  of    2/di?  +  r.( )      [3728a] 

depending  upon    the   same   angle,    or   upon      R^^  JV .  cos.  {i  T-\-L)     [3704].        This     [37286] 
gives  for     dR,     similarly  to  [3705^7],  the  expression      àR=nJ\r  .i  .  sin. [i  T-\-L)  .dt  • 

2» 
hence     2/d  R  = ^—  .  JV .  cos.  {i  T -\-  L)  ;     also  from  [3705a],  we  obtain  [3728c] 

Multiplying  the  sum  of  these  two  expressions  by     1  =  ji^  a^  [3709'],  we  get 

2/dil+..(^)  =  «^«^5«^.(^)-^-^^.aA-^.cos.(.-T+Z).  [3728.] 

Again,  if  we  multiply  [37276]  by     3  n^  a^.  {e  .  cos.  PV-}-  e^.  cos.  2  W],      we  shall  obtam     [.3728/] 

the  terms  of    [3702],  which  are  multiphed  by     3n^a.Sr;     and  as  we  have  to  notice 

only  the  terms  depending  on  angles  of  the  fonn     i  T  [3726'],     we  may  neglect  the  second     rg^gg  -, 

tenir  of  this  factor     e^.cos.2W  [3728/],     and  then  it  will  become     3  74^  a- .  e  .  cos.  W. 

In   multiplying   [3727è],  by   this  last    factor,   and   reducing   by  [20]    Int.,  the    term    jP 

produces  no  term  of  the   required  form,  and  each  of  the   other  terms     G,   G',   H  H' 

produces  one  ;  hence  we  finally  obtain 

3  n»  a .  5  r.  J  e .  cos.  W-{-  e^.  cos.  2  ?F|:=  f  «  V.  { (  6+  G') .  e^  cos.  i  T+He  e'.  cos.  {i  T-\-  W,'—  TV) 

+11' eé.  cos .  {i  T—  W;+  W)     ^^^^^''^ 
=  |«V.{(G+G').e2.cQs.i  T+Hee'.cos.  (iT+a— «')        ^^,„^., 

(3728*1 
+ifée'.cos.(îT— a  +  tj'). 

The  sum  of  the  second  members  of  the  expressions  [3728e,  z],  being  represented  by    a  Q 

rfs  irSr)  [3728ft] 

for  brevity,  the  differential  equation  [3702]   becomes      0  = -^^^ — -\-n^.r()r-\-a.Q^;     and 

we  find  by  mspection,  that  a  Q  is  equal  to  the  numerator  of  the  second  member  of  [3728],     [3728i] 

miltiplied  by   a^.      This  equation,  being  solved  as  in  [37116,  c],  gives     rôr  =  -^-^, 

usi^g^,  [371k/];  hence  we  get     '^  =  „Tg;ê^  =  „,(,„_"  ^(^^^„)  >     as  in  [3728].      [3728.] 


16  PERTURBATIONS  OF  THE  PLANETS.         [Méc.  Cèl. 

ç{G—G').e\sm.  i.{nt  —  nt  +  ;'—s)  ■\ 


Value  of 

6v. 


—  Hee.sm.\L{n't  —  7it-Jrs'  —  s)  —  zs-\-zi'l')        }  .*  (F) 

.  ,    ■     .a^A-r-]  —  r-, — r-;;  ■aJS  >.sm.\i.{nt  —  nt-\-^—£)-{-L\ 
[in'— in  \da/        [tn'—my  )  /    >        > 


[3729]  ^  V  = 


^1=1 


[3730] 


r  fi  r* 

If  we  put     -^     for  the  part  of     — ,      Avhich    depends    on    angles    of  the 


rt 


[3729, 


form      i,{n'l  —  n^  +  s' — s),t      and  is  also  of  the   order  of  the  square  of 

*  (2364)  The  value  of  5  d  [3729]  is  easily  deduced  from  [37155];  since  the 
denominator  ^(1 — e^)  is  the  same  in  both,  also  the  first  tenn  of  the  numerator;  and 
the  other  terms  may  be  obtained  by  a  calculation  similar  to  that  in  [3728« — »].  For  if  we 
multiply  the  expression  [3728c]  by  §andt,  and  [3728fZ]  by  2  a  n  d  t,  and  take 
the  sum  of  the  products,  we  shall  get 

«]       3aj7idtAR  +  2a.ncItui.(~)=\2n.a^('!^)  —  ^-.a:N'l.cos.{iT-{'L).dt. 
•'  '  \da  J        i  \da  J       n—n  >  \         ■       / 


Integrating  this  we  get  the  two  last  terms  of  [37156],  which  are  the  same  as  the  two  last 
terms  of  the  numerator  of  [3729],  or  those  depending  on  JV,  dJY.  The  only  remaining 
term  of  [37156]  is  the  second,  which  is  found  by  multiplying  the  differential  of  ?•  [3701] 

[3729i]      by ^  ;         whence  we   get         —  ^^^  = ^  .  5 e  .  sin.  Jr+  e^ _  si„_  2  Wi. 

■'  a-ndt  a~n  dt  a 

Sr 
Substituting     —   [3727],  we  may  neglect  the  term     c^.sin.  2AF,     and  the   term    F,    as 

in  [-3728^,  kc]  ;  the  other  terms  being  reduced  as  in  [18,  19]  Int.,  retaining  only  angles 
of  the  form    i  T;    we  get,  in  like  manner,  as  in  [3728A,  Sic]  ; 

—^±^==—-x.smW=l\{G-G'U^.smJT+Hc(^.s\n.{lT+W;-m-Hee\sm.(IT--l^^+W)\ 
a^n  dt  a 

[^''^^'l  =h-\{G-G').e^sm.{T+Hce'.sm.(iT+:s  -  z/)-Hee'.s\n.(iT -in+^n')]  ; 


[3729d] 


being  the  same  as  the  terms  depending  on  G,  G',  H,  H\  [3729].  We  may  remark, 
that  from  the  formulas  [3728,  3729],  we  may  deduce  others  similar  to  [3714,  3718],  in 
which  the  secular  variations  of  the  elements  c,  -m,  &,c.  are  noticed. 

I  (2365)    The  second  member  of  [3727]  being  denoted  by  F',  it  will  include  all  the 

or  .  ■  ■  ■ 

r3731ol     terms  of    — ,     depending  on  the  angle    i  T,    as  far  as  the  first  power  of  the  excentricities 
a 

(5  r 

[3726'].      Adding  to  this  the  expression    —,     depending  on  the  same  angle,  and  on  terms 
[37316]      of  the  order    e-,  ee',  Sic,  we  get    —  =ij"-f— ,     for  the  expression  of     —,    containing 


VI.  i.  §3.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  17 

the  excentricities  or  inclinations,  we  shall  have 

—  =  ^j^  +  i  .lGi-G'—F\.c~.  COS.  i.(n't  —  nt+  s'  — 0  V'''""'' 

+  i.  ATee'.cos.^î.  (n'f  —  «^  + s'  — s)  +  ^— ^'J  [3731] 

for  onglcB 
of  the 
second 
form. 


+  I .  He  e'.  COS. \ i .  (n' t  —  nt-\-^'  —  s)  —  ^  +  ra' | . 
In  these  three  expressions  i  must  be  supposed  positive  [3727'].  [3731' 


3.    The  great  number  of  inecjualities  depending  on  the   squares  of  the 
excentricities,   and  of  the  inclinations,  makes  it  troublesome  to  compute  all 
of  them  ;    and  we  must  be  guided  in  the  selection  of  those  which  are  of  a 
sensible  magnitude,  by  the  following  considerations.      First.    If  the  quantity 
in'-\-(2 — i).n      differ  but  little   from    ±?i;    then  the   one  or  the   other 
of  the  divisors     in' +(3 — i)  .  n,     in'-\-(\  —  i)  .  n,     in  the  formula  [3711],      ^^^^^^ 
will  be  quite  small,  and  by  this  means  the  expression  may  acquire  a  sensible 
value.      Second.    If  the  quantity    in' -{-(2 — i).n    be  small,  those  terms  of     [3733] 
the  formula  [3715],  having  this  quantity  for  a  divisor,  may  become  sensible,    slîecîîtg^ 
Third.    If  the  quantity     i .  (n' —  n)     differ  but  little  from    rh  n,    the  one    imp^tLt 
or  the  other  of  the  divisors     in' — (i-\-l).n,     in' — (i  —  l).n,      of  the      [3734] 
formula  [3728],  will  be  small,  consequently  this  expression  may  acquire  a 
sensible  value.      Fourth.    If  the  quantity     i  .  {n  —  n')     be  small,  the  terms 


terms   as    far  as  the  order      e^,    ce',    &ic.     inclusively.        Multiplying   this   by     —,      we 

r    i,r        rSr        ''      7-1/         t       i       /-  1  c    1  •  *■ 

get     -.  —  ==;  — g- .  f  .       In  the  first  member  of  this  expression,  we  may  put      -=1,     [37316'] 

as  in  [3726(Z],  and  in  the  factor  of  F',  we  may  use  the  value  [3726c]  ;  hence  we  shall  get 

^=:'^  +  F'.{  — 1— ic^+e.cos.  rr+ i  e"".  COS.  2  JV I  [3731c] 

=  ^— 5e^--F.cos.ir+F'.e.cos.  W;  [373W] 

the  second  of  these  expressions  being  easily  deduced  from  the   first,   by  observing,  tliat  of 
the  four  terms  comprising  the  factor  of   F'  [3731c],  the  first  teim,  — 1,    produces  nothing     [3731e] 
of  the  order  e^,  when  the  value  of    F'  [3727]  is  substituted  ;  the  second  tenn,     —  i  e^, 
produces  the  term  depending  on    F  in  [373  Ir/]  ;    the  third  produces  the  term  depending 
on   jP'  [3731c/]  ;  and  the  fourth  term,     ^  t^.  cos.  2  fV,     produces  nothing  of  the  proposed 
form  and  order.       Now  substituting,  in  the  term     F'.e.cos.JV  [313ld],  the  value  of  F',     [3731/] 
or  the  second  member  of  [3727],  reducing  the  products  by  [20]  Int.,  and  retaining  only 
angles  of  the  form    i  T,    it  becomes  as  in  [3731]. 
VOL.   III.  5 


18 


PERTURBATIONS  OF  THE  PLANETS. 


[Méc.  Cél. 


[3735] 


•General 
value  of 

R. 

[3736] 

First  form. 


[3737] 

[3738] 

[3739] 

Values  of 

^■>  y.  2, 

[3740] 
x',  y',  z'. 
[3740'] 


[3736a] 


of  the  formula  [3729],  which  have  this  divisor,  may  become  sensible. 
We  must  therefore  estimate  carefully  all  the  inequalities  subjected  to  either 
of  these  four  conditions. 

4.  The  quantities  F,  G,  G',  H,  H',  are  determined  by  the 
approximative  methods  in  the  second  book  [1016,  &c.,  372T].  We  shall 
now  determine  M,  N  ;  and  for  this  purpose  we  shall  resume  the  value 
of    R  [913,  &c.];* 

m'.[xx'-^yy'-^  zz') 


R^ 


m 


r'  being  the  radius  vector  of  m'.  We  shall  take.,  for  the  fixed  plane,  the 
primitive  orbit  of  m,  and  for  the  axis  of  x,  the  line  of  nodes  of  the  orbit 
of  m'  upon  this  plane.  If  we  put  v  for  the  angle  formed  by  the  radius  r 
and  the  axis  x  ;  v'  for  the  angle  formed  by  the  same  axis  and  by  /  ; 
also  7  for  the  tangent  of  the  inclination  of  the  two  orbits  to  each  other, 
we  shall  havef 

y  =  r  .  sin.  v,  2^0; 


a;  =  r .  cos.  v 


X  =^r .  cos.  V  ; 


y- 


r  .  sm.  V 


^^ 


f  .y .  sin.w 


(2366)    As  there  are  only  two  bodies  m,  m',  the  value  of  R,  X  [913,  914]  become 

n'.[xx'-\-yy-\-~z')       X  X 


R:= 


m' 


\  > 


M 

.■■'\ 


[37366]     and  by  using     r'^  =  a'^  +  if -{- z!^    [914'],  we  get  [3736]. 

f  (2367)  In  the  annexed  figure  72,  C  is  the  origin  of  the  co-ordinates,  or  centre  of 
the  sun;  C X,  C  Y,  C  Z,  the 
axes  of  X,  Y,  Z,  respectively  ;  M 
the  place  of  the  body  to,  supposing 
it  to  be  situated  nearly  upon  the 
[3740o]  plane  of  xy  [3737]  ;  M'  the  place 
of  the  body  in.  The  co-ordinates 
of  TO  ai'e  CA=x,  AM^y,  z=0  \ 
nearly  ;  those  of  to'  are  CA'  =  x', 
A'B'=y',  B'M'=z'.  Moreover 
angle.MC.^=«[924^],.lfC.^W, 

Then   in    the    rectangular    triangle        CAM,       we    have        C  A  —  C  M  .cos.  A  C  M, 
AM=C  AI.  sm.  A  CM,     or  in  symbols,    a:  =  r.cos.  «,    y  =  r  .sin.  i)  [3740].      In  the 


VI.  i.  §4.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  é,  7.  19 

Hence  we  get,  by  neglecting  the  fourth  powers  of  7,*  [3741] 

R  =  -j^  .  COS.  {V I') J-  .  3-3  .  i  COS.  (V V) COS.  (v^v)\ 


m  r  ,  ,        ,        m.y'     r 

— -  .COS.  (V I') .  —   .  !COS.  (V' V) COS.  (V'-\-V)\  Second 

.,.'2  V  /  ^^2i  V  -'  V'/l  fo,„  „f 


R. 

<i!.y~    rr'.{cos.(t)' — 1;) — cos.{v'-\-v)\  [3742] 


|r2— 2r;-'.cos.(D'— t>)  +  r'2}4  4      '    jr2_Orr'.cos.(D'— t') 4-r'2}2- 

We  shall  suppose,  as  m  [954,  956], 

-^.cos.(n'i— n^  +  s'— f)  — Ja-— 2aa'.cos.(n'^— n^  +  s'— s)  +  a'^î~^  [3743] 

=  I x.A^'K  COS.  i.(n't — nt-\-s — 0  ^t-',B<o. 

!«-— 2«a'.cos.(n'^— ni  +  s'— .^)  +  rt'2|-f=i2.jB»cos.ù(n7— n^  +  £'— 0;        [3^44] 

rectangular  triangle  CAM',  we  have  C^'=CJ/'.cos.^'CJ»f',  ^'Jf  ^^CJU'.sin.^'CJ»/; 
or  in  symbols,  x'=r'.cos.v'  [.3740'],  .4'J'/'=r'.  sin.  j;'.  In  the  rectangular  triangle  A'B'M', 
we  have,    A' E=A'M'.cos.B'A' M',     B' M'=A'M'.5m.B'A' M' ;    substituting  in  these     [3740c] 

1  r 

the  preceding  value  of  ./2' ./»/',    also     cos.B' A! M' ^=-—-, ,  sm.B'A'M= , 

/(1  +  7-)  v/(l  +  7^) 

we  get    y',  z'  [3740']. 

*  (2368)    If  we  neglect    7^    as   in    [3741],    we  shall  have     (1 +  73)-*=  l_  |  y2 . 
hence   we    obtain    from    [3740'],       y' =  i-' .  sm.  v' — J  7^.  r*.  sin.  u';      z'^='y^  .r'^.sm.^v' •     [3742a] 
substitutmg  these  and  the  other  values  [3740,  3740'],  in  the  first  member  of  [37426],  and 
then  reducmg  by  [24,  17]  Int.,  we  get  [3742c]  ; 

^ '^'+ i/ /+- ~'= '■'■'•  (cos. u'. cos. ij-f-sin.u.sm.t;')  — J 72.7-/. sin.  jj.  sin. o'  [3742i] 

^.irr'.cos.^!;'— î;)  — i72.rr'.jcos.(t)'-i')— cos.(«'-fî))}.  [3742c] 

Substituting  this  last  expression  in  the  first  tenn  of  R  [3736],  we  get  the  two  first 
terms  of  [3742].  Again,  if  we  develop  the  first  member  of  [3742e],  and  substitute 
r^=x"-+y^+z^    r^=x^+y'^+^'^  [3740,3740'],  also  the  expression  [3742c],  we  get  ^ 

(^-^)'+  {y'-yf+  (^-~)'=(-^"+2/'+~-)-2.  (^^'+yy+zz')+ (x'==+2/'2+^'2)  [3742e] 

=  ^-2-2;y.cos.(«'-v)+r'2}-|-i72.rr'.{cos.(î,'-i,)-cos.(z>'+^)}.     [3742/] 
Invc^lving  this  to  the  power     — ^,     we  get 

\{^'-xf+{y'-yfJr{^'-zf\-i=\r'-'2rr^.cos.{v'-v)-^r'^]-^ 


_3      [3742^:] 
^ Y^.rr. \coz.{v'—v)—co%.{v'\v) \ . {r^— 2r/.cos.(/— t;)-!-/^ j    2. 


substituting  this  in  the  last  term  of  [3736],  we  get  the  two  last  terras  of  [3742]. 


2»  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3744']  and  shall  represent  R  =  M.cos.\i. (n't —nt-i- s'—s)  +  2nti-K\  [3703] ,  by 
the  followmg  function  ; 

K™f]f  ^=      M'-'Ke''  .cos.\i.(n't—nt  +  s'—:)  +  2nt  +  2s—2z.\ 

[3^45']  -\-M^'Kee'.cos.\i.(n't—nt+s  —  s)  +  2nt-\-2s—^  —  ^'\ 

of  the  first 

'?^^^^«-,  +  M^~\  e'^cos.  I  i.(ii't—nt  +  i—s)  +  2nt+2i—2z,'\ 

[3745'"]  +  M^'K  y^  .cos.\i.(n't—nt+s'—s)  +  2nt  +  2s—2n  \  ; 

n.       n  being  the  longitude  of  the  ascending  node  of  the  orbit  of  m'   tipon  that 
[3746]      fyj-  j^^  counted  from  the  line  which  is  taken  for  the  origin  of  the  angle    ni  +  f. 
We  have,  as  in  [669], 

[3747]  -=  1  +  ^e- — e.  COS.  (ni+£  —  -a) — i  e".  cos.  2  .  (nt-\-£  —  ^i)  : 

[3748]  v  =  nt^i  —  n  +  2e.  sin.  (n  i  +  s  —  ^)  +  |  ^''  sin.  2  .  (n  t  +  e — a). 

From  these  we  get  the  values  of    —,    v',     by  marking  with  one  accent,  the 
quantities  n,  e,  s,   &c.       Then  we  have,  as  in  [955],  the  product  of 

2  .  A  (".  cos.  {i  .  (7i't  —  nt  +  .='—  s)|, 

by  the  sine  or  cosine  of  any  angle    ft-\-I\     which  is  equal  to 

[3749]  2  •  A''  ■  "^i  li-(n't-n  t  +  /— =)  +ft  +I\. 

Hence  we  easily  obtain* 

[3750]       M-^=    f.J.-.(4^-5)..^(')  +  2.(2.-l).«.('^)  +  «^('^)5; 

Values 

pondins  4^^-^  ^       ^         ^        \    da     J  \    da     J  \  dada  /  ^ 

to  tlie  first 

^^,    M-.=    |.^,;_.,.(4;-3).^--..(.,--a,...(^')+...C^)^, 

[3750'"]     M '31=— —  .  «  a'.  £''-'1 . 

8 

[3750a]  *  (2369)  In  [952,  953]  we  have  r  =  o .  (  1  +  wj  ;  v  =  vt -}-s  —  U-\- v,;  the  terni  n 
being  added  to  conform  to  the   present  notation.      Comparing  these  witli   [3747,  .?748], 

[3750t]  we  get  the  following  values  of  u^ ,  v^ ,  also  the  similar  ones  of  w/,  w/,  using  the  abridged 
symbols  [3726a]  ; 

[3750c]  «,=  — e.cos.^F  +  4  e^  — J  e^.  cos.2  ^F  ;       t),  =2e  .sin.  ^F  +  f  .  e^siii.2  TF  ; 

[3750rf]  «;  =  —  c'.  COS.  W'-\-^e"^—l  e'- .  cos. 2  W  ;       v;=2e'.  sin.  ?f '+  f  .  e'^ .  sin. 2  W; 


M.  ï.  §4.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  21 

and  in  the  case  of    i=\     [3150y,  ?/'],  we  have 

4     a'*        8 

Finding  the  squares  and  products  of  these  quantities,  then  reducing  them  by  [17 — 20]  Int., 
retaining  merely  the  temis  of  the  second  degree  in  e,  e',  y,  which  are  the  only  terms  now 
under  consideration  [3702'],  we  obtain  the  following  system  of  equations.  In  these 
expressions  we  have  substituted  for  JV  its  value  W  =^  T -\-  IV -\- zs — -a'  [3726a],  [3750c] 
in  order  that  the  quantity  n't-\-  e'  may  not  appear  in  the  tenns  of  R,  except  in  connexion 
with  i,  as  in  the  assumed  form  of  these  terms  of  R,  given  in  [3745,  &c.,  957].  The 
numbers  prefixed  to  the  formulas  [3750/]  express  the  order  of  the  terms  in  the 
value  of   R   [957]. 

=  Je'2  — Je'2.cos.2.(r+  ?F+t3  — ^); 

=  f  Ê'2.sin.2.(r+  ?r+«  — î/); 

=  fe^.sin.  2^; 

=  ie^-f  le'-i.cos.  2  7F; 

'==  è  ee' .  cos.  (r+  w  —  ^')  +  A  ce',  cos.  (7+  2  W-\--a—Ta')  ; 

=       Je'2  4-Je'2.cos.2.(r  +  ?F+«  — ^'); 

=  —    fe'.sin.  (T^-^  — ^)— ee'.sin.  {T +2  TV+zi—z,'); 

=  —     e^.sin.  2fF; 
'  =  _     e'^.sm.2.{T-i-W+z,  —  z/); 
,=  ce'.sin.  (T+w  — •n')  — ee'.sin.  (r+2  W -}- ■a—zy')  ; 

=       2e'2  — 2e'2.cos.  2.(T+  ÏV -^ zi  —  zi')  ; 

=      2ee'.cos.  (T+1^  — to')— 2e'2.cos.  (T+2  ^F+a— to'); 
=      2e^  —  2e^cos.2W. 

Substituting  these  in  [957],  we  shall  obtain  the  terms  of  R  depending  upon  M'-''\  M'-'^\  M'^', 
[3745,  kc.].      The  ternis  of  the  fonn    iVT^',    arising  from  the  terms  of    z,  a/,    in  the  two     [3750g] 
lower  lines  of  the  value  of  R  [957],  will  be  considered  hereafter  in  [3750m,  &;c.].      In 
making  these  substitutions,  we  must  use  the  following  formulas,  which  are  the  same  as  those 
in  [954f,  955a,  955/],  changing   TV  into   TV^,  to  prevent  confusion  in  the  notation. 

COS.  JV^.iX.A  <'> .  cos.  i  T  ==  i  2  .  ^«  .  COS.  (  J  T  +  TV,)  ;  [3750^] 

sin.  TV, .  J  2  .  iA^'l  sin.  {T=  —  ^2.iA  «  .  cos.  (i  T  +  TV,)  ;  [3750i] 

COS.  fT  .is.i^^ra.  COS.  i  r=i  2  .  i^^w.cos.  {i  T+  W,).  [3750A] 
VOL.  III.                                   6 


2 

"/ 

3 

"/ 

4 

Î'/ 

5 

^', 

6 

<- 

7 

v,u; 

8 

nr- 

9 

u,v; 

10 

uv. 

11 

w>; 

12 

ujv. 

13 

v',^ 

14 

v,v,' 

15 

r,2 

[3750/] 


22  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cèl. 

We    shall    represent       R  =  N.  cos.  \i  .  (n' t  —  7it  +  I'—s)  +  L\      [3704] 

We  shall  consider  the  terms  depending  on  each  of  the  factors  M'-''\  iV/'",  M'--''  [3745,  &;c.] 
separately;  and  in  the  first  place,  shall  take  the  tenns  of  the  form  M'^Ke^-cos.  {iT-\-2W). 
These  are  evidently  produced  by  the  factors  sin.  2  IV,  cos.  2  TV,  which  occur  in  the  terms 
of  [3750/],  marked  2,  5,  6,  10,  15;  reducing  the  products  by  the  formulas  [3750A— A:]. 
These  five  terms,  marked  in  the  order  in  which  they  occur,  without  reduction,  supposing  them 

all  to  have  the  common  factor      ^  •  c^-  cos.  {i  T-(-2jF),      and  omitting  2  for  brevity,  are 


[37502] 


This  expression  is   easily  reduced  to  the   form  of  the  coefficient  of    —,      in   the  value 

of  M'-"''  [3750].  Proceeding  iii  the  same  manner  with  the  parts  of  the  terms  7,  9,  12,  14 
[3750/],  depending  on  the  angle  T+2?F-f-w  —  zs',  we  find  that  they  produce 
in   R  [957]  terms  of  the  form     iV/^'^e  e'.  cos.  {{i  +  1) .  T+  2  JV -{- zs  —  zs" } ,     which  may 

[3750n]     be  represented  by      — ^  .  e  c'.  cos.  {(i  +  1)  .  T+ 2  JF+ is  — î/^,      multiplied    by  the 

4 

following  expression,  which  includes  the  terms  as  they  occur,  without  any  reduction  ; 

[3750O]  -««'(7a^)  +  2*«-(^)-2-'(77-)  +  4^'-^"- 

We    may   change   in    this    i    into    i  —  1    [.3715'],    and    then  we  get    for  the  coefficient 
[3750;)]     of     —  j.ce'.cos.(ir+2yF+ro— ra'),      or     — j  .  e  e'.  cos.  {i  T~{-2nt -{-2  s—zi— a'), 

an  expression  which  is  the  same  as  the  coefficient  of  — — ,  in  the  value  of  il/"'  [37.50']. 
Again,  the  terms  3,  4,  S,  11,  13  [3750/],  depending  on  the  angle  2.  (r+  (F+ra— n'), 
produce  in  R  [957],  terms  of  the  form  M^-\  e'^  cos.  { [i  +  2) .  r+  2  fF+  2  ro  —  2^}  ; 
[3750?]  which  may  be  expressed  by  ''^  .c'^.co5.\{i-\-2).T -{-2W -^2is  —  2«'|,  muhiplied  by 
the  following  function,  which  includes  all  these  terms  as  they  occur,  without  reduction  ; 

or,  as  it  may  be  written, 

[3750,-']  i.(4i  +  5).^'''-2.(2i+l).«'.('^)  +  a'^.(^). 

We  may  change   in  this    i    into    %■ — 2    [3715'],    and  then  we  have   for  the   coefficient 

[37505]     of     -.c'2.cos.(iT+2?F+2^— 2j:'),      or     ^.  cos.  (»  T+2ni  + 2s  — 2^'),     the 
8  o 

m' 
[3750«]      same  quantity  as  the  coefficient  oî    —,     in  the  value  of   M^-'   [3750"]. 


VI.  i.  §4.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e\  7.  23 

by  the  following  terms  ;  *  Terms  of 

^,  -.-.-,«.  .  .  -  »  depentlinff 

R=        ^W,  COS.  I.  (n't  — 71  t+s'—e)  [3752] 

on  angles 

+  N^'K  ee'.  cos.  [i .  (n't  —  n  t  +  e'— s)  +  w  —  ^'|  "'[ih^-] 

second 

+  iV'^' .  e  e'.  COS.  ^  z .  (n7  —  ?i  ^  +  e'  —  s)  —  ra  +  ra'  |  ;  'farsa"] 

We  shall  now  notice  the  terms  depending  on    z,  z ,    which  were  neglected  in  [3750^]  ; 
these  are  the  same  as  those  depending  on    7^,    in  the  value  of  jR    [3742].      As  we  neglect 
terms  of  a  higher  order  than    7-,    we  may  substitute,   in  these  terms,  the  values       r  =  a; 
r'  =  a';       v=^nt -{-s  —  Ii  ;       v  =^n' t-\- ^  —  U  ;       v' — v  =  n't-—nt'\-s  —  s=T;     [3750u] 
v'-\-v  =  n't-[-nt-{-^-{-e  —  2ll=T-{-2nt-{-2s  —  <iin;  hence    this    part    of 

R  [374-2]  becomes 

R  =  —'l^  .-^.{cos.  T— cos.(jr+2n<  +  2e  — 2n)j 

,^  ,  ■  [3750i>] 

*       \a? — Saa.cos.  T-|-«  P 

Substituting,  in  the  last  term,  the  value  of  the  denominator  [3744],  namely   \  ^.B'^'K cos. iT, 
and  reducing  by  means  of  the  formula  [3750^],  it  becomes 

m'ya  f  _-^.cos.  T+4"-cos.  (T+2n<4-2s— 2n)  ) 

^=~T~-<        a-  a~  V        [3750k'1 

(+|aa'.2.J5('\cos.(J+l).r-iaff'.2.5w.cos.{(i+l).r+2»U  +  2s-2nn 

The  last  temi  of  this  expression,  changing   i  into   i — 1    [3715'],  becomes 

X.aa'.  2.  B''-i'.  COS.  (ir+ 2  îii  +  2£  —  2n);  [3750i] 

which  is  of  the  same  form  as  [3745'"],  and  is  equal  toit  by  putting  M'-^'^  = .  a  a' .  S .  B^''~'\ 

8 

as  in  [3750'"].      In  the  case  of   i  =  l,    the  term  [3750z]  becomes 

—  ^.^a  a'.  S^»^  COS.  (  T  +  2  n  ^  +  2  £  —  2  n)  ;  [3750t/] 

connecting  this  with  the  second  term  of  [3750f<'],  namely, 

^.^.cos.(T+2n<  +  2j— 2n);  [3750)/'] 

and  putting  the  whole  equal  to  this  value  [3745'"],  we  get,  for  this  case,  the  same  value 
of    JW ">,    as  in  [3751  ]. 

*  (2370)    By  proceeding  as  in  the  last  note,  we  shall  find,  that  the  substitution  of  the 
values  [.3750/]  in  iî  [957],  produces  terms  depending  on  the  angle    i  T,    iT+zs  —  ra',     [3752a] 
ïî"— «  +  «',   as  in  [3752—3752"],  without  W,  which  occurs  in  the  fomis  [3745—3745'"]. 


24  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

and  we  shall  have 

CoefB- 

;3753]      JV(»)=-^.5(e«+e'=).r4i''.^«>-2a.f^')-a».f^)]-$.aa'.[B('-')  +  5«^»]^; 

depending  ^C.  L  \  da    /  \   da-     /J  2  ) 

on  angles 

,  4f^'  ^        '       \    da    /         ^        '       \   da     J   '  \dada   JS 

form. 

m..,  ^».=   -.^,.,+„,^..„+,.(..+,,..(^')+,.,+,).,.(^>)+„,(^)|. 


We  shall  calculate  these  terms  separately,   commencing  with  the   angle    i  T,     which  is 

[37525]     produced  in    R    [957],    by  the    substitution  of  the    terms    ^e^,    Je'^,    occurring    in   the 

terms   of  [3750/],    marked  2,  3,  6,  8,  13,  15.       These   quantities  produce  in    R,    the 

expression —  .cos.  i  T,      multiplied  by  the  following  terms,  WTitten  down  in  the  order 

in  which  they  appear,  without  reduction,  and  omitting  2  for  brevity  ; 

Now  if  we  multiply  the  first  of  the  equations  [1003]  by    —  1,    and  the  third  of  these 
equations  by     —  |  ;     the  sum  of  their  products  will  give 

,  /dA^i)\       .    ,„  /ddA<ii\  fd.»o\  AW^(.)\ 

substituting  this  in  [3752f],  we  find,  that  the  coefficient  of    e'^    is  the  same  as  that  of    c', 
and  the  whole  expression  becomes 

[3.5.,,  _^.(..+  ..)4.i,^»_„.(l^)-i,...(^-^);.eo..-r. 

To  this  we  must  add  the  third  term  of  [37502^],  depending  on     cos.  {i -\- I)  .  T,     which, 

[3752/]    by  changing  i  into    i—l,   as  in  [3750c),  becomes      —  .  J aa'. 2. jB^'-i'. cos. i  T.       The 

expression    [375'2e]    is  the   same   for    —i,    as    for    +i;    because     A'-'^  =  A'''^   [954"]. 
Moreover,  the  term  [3752/],  by  the  same  change  of  i,  using     J?(-i-i)  ==  ^c.+D    [956'], 

[3752g-]     becomes      '^  .  i  a  a'.  2 .  J5''+" .  cos.  i  T.      Hence,  if  we  use  only  positive  values  of  i,   we 

must  double  the  fonction  [3752e],  and  add  to  it  the  two  expressions  [3752/  g]  ;  the 
sum  of  these  three  ftmctions,  being  put  equal  to  N'-^'' .  cos.  i  T  [3752],  gives  the  same 
value  of  iV^*",  as  in  [3753].  In  the  case  of  i  =  \,  this  sum  must  be  increased  by  the 
[3752/il  first  term  of  [3750w]  ;  by  which  means  iV^°^  is  increased  by  the  quantity  given  in  [3754]. 
The  case  of  i=0,  which  is  separately  considered  in  [3755'''],  produces,  in  R,  the 
following  expression,  which  is  deduced  from  [3752c,/],  by  putting    i=^0; 


VI.  i.  §4.]  TERMS  OF  THE  SECOND  ORDER  IN  c,  e',  y.  25 

In  these  three  last  expressiotis  i   is  supposed  to  he  positive  and  greater  than    [3753'"] 
zero.      Incase    i  =  \,    we  must  add  to  iV""  the  term    —  ^.  ^^  [3752/i].      [3754] 

It  is  more  convenient,  for  numerical  calculations,  to  have  the  differentials 
relative    to    only  one    of  the    two    quantities     «,    a',     in    these    formulas.* 


Proceeding  m  the  same  manner  with  the  angle  iT-^-zi  —  w'  [3752'],  we  find,  that 
terms  of  this  form  are  produced  in  R  [957],  by  the  substitution  of  the  parts  of  the  terms 
of  [3750/]  depending  on  the  angle  T-f-ra  —  i^,  and  marked  7,  9,  12,  14;  reducing 
them  by  means  of  the  formulas  [954c,  955a,/].       Hence  this  part  of   R   becomes  equal 

to      ~.ee'.cos.\{i  -\-\)  .T -\--a  —  -m'],      multiplied  by  the  following  expression,  retaining    [37524] 

the  terms  according  to  the  order  of  the  numbers,  without  any  reduction  ; 

aa'.f -— — )  — 2ia.  (  — -  )  — 2ia'.    — —  )  +  4  i^.  ./î*'^.  [3752q 

\dada  /  \  da  /  \da   / 

Changing   i   into    i  —  1,    in  [3752À:,  Z],  we  find,  that  this  part  of  R   maybe  represented 

by  .  ee'.  JV^''.cos.  {i  T+ra — ra')    [3753']  ;     observing,  that  this  change  in  the  value     [3752m] 

of    i,    reduces  the  expression   [3752Z]   to   the  same  form  as   the  factor  of     —,     in  the 

value  of  iV"'  [3753'].     We  must  retain  only  the  positive  values  of  i  in  [3752',  3753']  ;  for 

if  we  ciiange  the  sign  of  Î,  the  expression    cos.  (i  T-j-w— ■zs'),    becomes    cos.(  —  iT-\-vs—-a')     [3752)1] 

or    COS.  {i  T — ■n-j-'sj'),    which  is  of  tlie  same  form  as  [3752"].      Hence  it  appears,  that  we 

may  deduce    JV'-'   [3752"]  fi-om    iV*'>    [3752'],    by  changuig  the  sign  of  i.     Performing     [3752o] 

this  operation  on  [3753'],  we  get  [3753"],  using  ^^-'-i>  =  ^('+i>  [3752/'].     Finally,  the 

case  of    i  =  0,    is  found  by  putting    i  =  0    in  [3752ot],  or  in  the  similar  terms  depending    [37520"] 

on  JV^2i  [.3752o];  observing,  that  when    i  =  0,   the  expressions  JV'^',  JV'2>  [3753',  3753"] 

become  equal  to  each  other  ;  and  this  part  of  R  becomes 


f . ...  [  4^...+  .„ .  (1^)  +.»..  (•-■)  +,y.  (1^')  I  .  e„.  („-.,.  ,,.„ 

*  (2371)  In  making  the  reduction  of  M<"  from  [3750']  to  [3755],  it  will  be  convenient  to 
use  the  abridged  symbols        a™ .  (-^^j  =  ^ï  ;         a"" .  (Ç^')  =  .//'<::'  ;       and  as  the     [3755o] 
index  n  is  the  same  for  all  the  terms  depending  on  M''^\  we  may  neglect  it,  and  put  simply 

'  [37556] 

VOL.  III.  7 


26  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

This  is  obtained  by  means  of  [1003],  from  which  we  get 

[3755]      JtfU,__^.^(2,-_2).(2,-_i).^(-«+2.(2;-l).«.(!^)  +  «^(î!^')^; 
[3755']      Jlf(^)=       |\^(4i^_7i  +  2).^^->  +  2.(2z-l).«.('-fp)  +  «^(''';;;^^^ 

Reduced 
values. 

[3755"]      ./V-=       ^.^(2._2).(2.--l).^<--2«.('^)-«^(^)5; 
[3755'"]    JV^^>==      -'.^(2^•  +  2).(2^•  +  l).^u4-n_2«.(^'^^_„..(^''f^^^. 

[3755i>]  5,     The    case    of     i  ^  0      deserves    particular   attention.         We    shall 

resume   the   expression   [923],    and  shall  consider,    in    the  first  place,    the 

and  the  same  symbols  may  be  used  in  the  reduction  of  Jlf' -' ,  .A'"'" ,  JV'-' .  Then  the 
coefficient  of  — ^m',  in  the  value  of  M'-^''  [3750'],  will  become,  by  the  substitution  of 
the  first  and  second  formulas  [1003], 

[3755c]  =  2.  (i  —  1) .  {2  .  (i  —  1)  +  1 }  .  ^„+  ^4  i  — 2^ .  ^,  +  A., 

^{2i  —  2).(2i  —  l).A,-^2.{2i  —  l).A,  +  A,; 

which  is  the  same  as  the  coefficient  of   — J  m'    in  [3755].       In  hive  manner,  the  coefficient 

of    — ,    in  [3750"],  becomes,  by  using  the  first  and  third  of  the  formulas  [1003], 

8 

(;_2).(4i— 3).^o  +  2.(2i  — 3).  lA,  +  A,l  +  {2Ao  +  4.A,  +  A,\ 
f^^^^'^J  =\{i-2).{ii-3)+4i  —  4l.^,  +  2.{2i-\).A,+A,; 

which  is  easily  reduced  to  the  form  of  the  factor  of    —,     in  M^~'>   [3755'].      Again,  the 

factor  of    i  m,     in  the  value  of    iV'"  [3753']  becomes,  by  the  substitution  of  the  values 
in  the  first  and  second  formulas  [1003]  ; 

A.{i  —  \f.A,—2.{l—\).A,  +  2.{i  —  \).\Jl^+A,\  +  \  —  2A,—A^\ 

^2.{i—\).\2.{i—\)  +  \\.A,  —  2Ay  —  A^; 

which  is  the  same  as  the  coefficient  of    \m,     in  tiie  value  of    jV"'  [3755"].       From  this 
we  may  easily  obtain    A*'-',    by  merely  changing  the  sign  of    i,    as  in  [3752o]. 

*  (2372)  The  terms  of  R  depending  on  i  =  0,  are  given  in  [3752»,  3752p]  ;  they 
are  independent  of  n  t,  n'  t,  and  produce  in  ^  d  a  secular  equation  [3773]  ;  and  on  this 
account,  they  are  carefully  computed,  though   it  is   finally  found,  in    [4446,  4505],    that 


[3755e] 


VI.  i.  §5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  7.  27 


term 


— 5^ ^ ^,       of  the  expression  of    d5v,     given   by   this    [3755"] 


On  the 

secular 


'■dv 
formula.       We  have,  as  in  [1037],  by  noticing  only  the  terms  affected  with    pi"  of 
the  arc  of  a  circle  n  t* 


r 
a 

S  r 
a 

—  I  m'.  (h  C  +  h'  D).nt.  cos.  {n  t  +  e)- 


^  1  _  /i .  sin.  («  t-\-i)  —  l.  COS.  (n  t  +  i);  [375G] 

=  \m'.{lC  +  l'  D).nt .  sin.  {n  t  +  s)  [3756'] 


they  are  insensible.       To  reduce  these  terms  of  R    to  the  form  [3764],  we  may  use  the 
following  symbols,  given  in  [1022,  1033]  ; 

A:=c.sm.«;  Z  =  e.cos.is;  A'=  e'.  sm.  w' ;  r  =  e'.cos.  ra' ;         [3756a] 

e2=A2+/2.  e'2  =  A'2+Z'2;  [37566] 

y.sin.n^y— p;         y  .cos.n  =  q' —  q  ;         7^=(p'—p)-+{q'—lf-  t^^'^^'^l 

Now  substituting,  in   [3752t],   the  values  of    c^,    c'^,    y^    [3756e,  c],  they  will   produce, 
respectively,  the  first,  second,  and  fourth  lines  of  the  expression  of  R    or    ô  R    [3764]  ; 
observing,  that,  by  using  the  sign    S,    as  in  [917'],  these  terms  of   R   may  be  represented     [3756rf] 
by    &R.      The  term  [3752j7]  produces  the  thii-d   line  of  the  same  value  of    5R;     for 
we  have,  by  using  [3756a], 

e  e'.  cos.  (a  —  -n')  =  e  e'.  (sin.  ^s  .  sin.  a'  +  cos.  -m  .  cos.  z^)  =  A  h'  +  /  Z'  ;  [3756e] 

substituting  this  in  [3752p],  it  produces  this  term  of  &R  [3764],  having  the  factor  hh'-\-ll'. 

This  value  of  oR   is  to  be  used  in  the  formula  [923],  to  compute  the  part  of    5v,    which     |-.,„„ 

is  independent  of  the  angles    n  t,  n't;    and  of  the  second  degree  in    A,  A',  /,  V ,  &.C. 

*  (2373)    The  object  of  the  present  computation  is  merely  to  ascertain  the  part  of   à  v, 
mentioned  in  [.3756/],  by  means  of  the  expression  of  dàv  [923].      This  may  be  reduced 

to   the    form    [-3757^],    by  observing,    that       r  i?' =  r  .  ("^  W  «  .  (^)    [928',  962],     [3757o] 

and  that  we  have,  identically,     2  r .  5  R'  -{-  R' .  6  r  ^2  &  .  {r  R!)  —  R' .  5  r.      From  the  first     [37574] 
of  these  equations,  we  see  that    R'   is  of  the  same  order  as    R,  or  of  the  order   m  ;  and 
by  rejecting  tenns  of  the  order    m'^,    as  in  [-3768'],  we  may  neglect  the  term     — R'.Sr, 
and  then  this  expression  [37576],  by  the  substitution  of  r  R'  [3757a],  becomes 

'd'>R\  [3757e] 


2r.5R'-\-R'.ôr=2S.{rR')  =  2a.(  ^) . 


Substituting  this  in  [923],  also  the  value  of   r^dv  [.3759],  we  get 

'dûR 


d.{2r.d5r+drJr)  +  dt^.\^3fôàR+^a.(^)]  ^^^^^^^ 


1    r        

a'J.nrf<.v/(l— e9) 


28  PERTURBATIONS  OF  THE  PLANETS.       [Méc.  Cél. 

These   give,    by   noticing   only   the   terms   depending   on   the   squares   and 
[3757]     p^fjdy^cis  qJ-    ji^  i^  ]i'^  i'^     independent  of  the  sines  and  cosines  of    nt  +  e, 

and  its  multiples  * 
[3758]         d.(2r.d5r  +  dr.&r)  =  —''^^^^^^.\(h'+n.C  +  (hh'+in.D\. 


In  this  we  must  substitute  SR  [3764],  and  those  terms  of  dr,  S  r,  which  produce 
quantities  of  the  form  and  order  mentioned  in  [3756/].  Now  these  quantities  will  be 
obtained  by  selecting,  from   the  general  value  [1037],  the  three  terms  contained  in  the 

r  Ô  V 

[3757e]     second  member  of  [3756],  for    -;   and  the  terms  in  the  second  member  of  [3756'],  for    — . 

It  is  unnecessary  to  use  any  other  tenns  of  a  higher  order  in    h,  1,  &c.  ;    for  if  we  retain, 

in    -,   any  teim  of  the  order  h^,  hi,  1%  connected  with    sin.2.(?i^4-6)   or  cos.2.  (m^  +  s), 
a 

it  must  also  be  connected,  in  [3757rf],  with  terms  of    —,    or  of  its  differential,  of  the  same 

[3757/]     forms  and  order,   producing  terms  of  the  fourth   order  in    h,  1,    and   independent  of  the 
angles    n  t,  n'  t,    which  are  neglected  in  this  article.      The  same  remarks  will  apply  to 

other  terms  of   - ,    depending  on  higher  multiples  of  the  angle    nt-{-s.      Having  adopted 


[3757g-]     this  form  of    -,    it  will  be  unnecessary  to  retain  any  terms  of    —     [1023,  1037],    except 
a  o 

Sr 
those  in  the  second  member  of  [3756]  ;    for,  though  other  terms  in    —    [1023],  of  the 

[3757/i]  forms  P,  P'.  sin.  ()i  / -(- s),  P".  cos.  {nt  -\- s),  might  produce,  in  2r  .d  è  r-\- dr  .&r, 
quantities  independent  of  the  sine  or  cosine  of  the  angle  nt  -\-e,  or  its  multiples  ;  yet 
if  we  notice  only  terms  of  the  order  m',  they  will  vanish  in  its  differential,  which  occurs 
in  [3757d,  3760]  ;  and  this  does  not  happen  with  the  arcs  of  a  circle  retained  in  [3756'], 
as  is  shown  in  [3760]. 

*  (2374)  In  finding  the  terms  of  2  r  .  tZ  i5  r -|- <7r  .  5  r,  of  the  order  m',  it  is  only 
[3758o]  necessary  to  notice  quantities  of  the  form  Q  ■  «  t.dt,  containing  the  arc  of  a  circle  n  i, 
Q  being  constant  ;  for  if  the  function  contain  any  constant  term,  or  elements  of  tlie  planet's 
orbit,  it  will  either  vanish  from  its  differential  '  [3760]  or  become  of  the  order  7«'^,  &;c.  ; 
and  terms  depending  on  the  sine  and  cosine  of  nt-\-s,  ai-e  neglected  [3757].  Substituting 
r  [3756],  and  its  differential,  in  the  first  member  of  the  following  expression,  we  get 


[37585] 


2  r  .  d  5  r  -{-  d  r  .  5  r  =  \2  a —  2  ah  .  sin.  [nt  -\-  e)  — 2al.  cos.  [ni  -\-e)\  .d  S  r 
4-  I  —  ah  .  cos.  {nt-\-s)  -{-  al .  sin.  [nt  -\-e)] .  n  dt .  or  ; 


in  which  we  must  substitute   the  values  of     S  r ,    d  Sr.        Now  if,    for  a   moment,    we 
[3758c]     put     im'.a.{lC-Ji-rD)  =  L,     im'.  a  .{h  C-{-h'D)  =  H,     we  shall  get,  fiom  [3756'] 


VI.  i.  ^5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  29 

We  then  have      r"  dv  =  a"  n  d  t .  \/ï^^    [1057];    hence  we  shall  obtain      [3759] 

d.{Or.dSr+dr.Sr) m'.ndt     <(^j^,_^pyc+(hh'  +  ll').D\.  [3760] 

r~  dv  4 

We  have,  in  [1071], 

(0,  1)  =  —  1  m'  nC;  [^^^rn'riD;  [3761] 

therefore  * 

d.{2r.dSr-{-dr.Sr)  _,_^^,^Q^^y  ^,^,j^p^  _  ^^  _  (hh'+ll')\.  [3762] 

r^  dv 

We  shall  now  consider  the  term     — ^-^, ,     of  the  same  formula  [923] 

r-'  dv 


[3758d] 


and  from  its  difterentlal,  the  following  expressions,  retaining  only  the  tenns  which  contain 
the  ai-c  of  a  circle,  as  in  [3755']  ; 

S  r  =L  .n  t  .  sin.  {n  t  -{- s)  —  H  .nt .  cos.  (»  t-\-s); 
dSr=L.7i^.  tdt  .COS.  {71  t-j-s)  -{- H .  nP.  t  d  t  .sm.  (jii  +  e). 

Substituting  these  values  of  &r,  dSr,  in  the  first  members  of  the  equations  [3758e], 
reducing  by  [17 — 20]  Int.,  retaining  only  the  terms  containing  the  arc  of  a  circle, 
independent  of  the  sine  or  cosine  of    nt-^  e,     we  get 

'2a.dSr  =  0; 

—  2  a  h.  s'm.  {nt  -{-  e)  .  dSr  =  —  ahH  .rfitdt  ; 

—  2al.cos.{nt+s).d6r  =  —  alL.n^tdt;  [3758e] 

—  ah  .  cos.  (nt-\-s).ndt.5r^iahH.7i^tdt; 
-[-    al  .  sin.  [nt  -{-  s)  .nd  t  .5r  =  ^  al  L  .  n^t  dt . 

The  sum  of  the  tenns  in  the  first  members  of  [3758e]  is  equal  to  the  second  member 
of  [37586]  ;  consequently  the  first  member  of  [3758J]  is  equal  to  the  sum  of  the  second 
members  of  [375Se]  ;  hence  we  get 

2r.dSr  +  dr.5r=  —  iahH.n^tdt  —  ialL.n^tdt.  [3758/] 

The  differential  of  this  expression  becomes,  by  resubstituting  [3758c], 

d.{2r.dSr  +  dr.Sr}  =  —  in^a.dt^.{hH-{-lL) 

Dividing  this  by  the  expression  of  r'^dv  [.3759],  neglecting  the  divisor  \/{l  —  e^),  which 
only  produces  terms  of  the  fourth  degree  in    h,  h',  e,  &c.,    it  becomes  as  in  [3760]. 

*  (2-375)    Substituting  the  values  [3761]  in  [3760],  we  get  [3762].  [3762a] 

VOL.   III.  8 


[3758g] 


30  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cèl. 

or  [3757 d'\.       If  we  notice   only  the   secular  quantities  depending   on   the 
[3763]      squares  and  products  of  the  excentricities  and  inclinations  of  the  orbits,  we 
shall  have,  by  the  analysis  of  the  preceding  article  [37ô6d—f], 

Pan  of  V  \  ^  \ 

6R, 


..™-  +f(Mwj4....  +  .„.('-)+2...(M^)+„..(J^), 


ponding  to 

t=0. 


[3765] 


[3766] 


m 

p,  p'l  q,  ([,    denoting  the  same  quantities  as  in  [1032].      Hence  we  easily 
obtain,  from  Book  II,  ^  55,  59,* 

aw.<5i2  =  — 1.(0,  l).{/r  +  r  +  /t'2  +  Z'2|  +  [^].j/t/t'+n'i 

which  gives  f 

an.àùR  =  dh.\  —  {Q,\).h+\^.h'\—dl.  \(0,\).l—[^.l'\ 

-(0,1). dp. (p'-p)-(0,l)-dq.(q'-q). 


*  (2376)  If  we  multiply  [3764]  by  an,  we  shall  get  the  value  of  aii.ôR,  which 
may  be  easily  reduced  to  the  form  [3765]  by  the  following  considerations.      The  coefficient 

[3765a]     of   h^-^P    is  equal  to '—   [1073],   and  the  coefficient  of   h'^-^-l'^    is  of  the  same 

value  ;  as  evidently  appears  by  the  substitution  of  the  expression  [3752rf].  The  coefficient 
of  {p'—p)^+ir/—fjf,  in  this  product,  is  ^  m' ?i .  «^  a'.  B"'==  J  .  (0,  1)  [1130]. 
Lastly,  the  coefficient  of  h  h'-\-Jl'  in  this  product,  is  evidently  equal  to  |  m  n,  multiplied 
[37656]  by  the  expression  of  D  [1013],  and  this  is  shown  iii  [1071]  to  be  equal  lo  [ôTÎ], 
as  in  [3765]. 

t  (2377)  In  taking  the  differential  of  [3765],  relatively  to  the  characteristic  d  [37056], 
we  must  consider  h,  I,  p,  q  as  the  variable  quantities,  and  h',  I',  p,  g'  as  constant  ; 
and  then  we  shall  get 

an  .do  R  =  —  {0,1) .  {h  d  h  -j-ld  I)  +  [^]  .  {h'd  h -^r  d  I) 
[3766a] 

^  (0,1). \-{p'-p).dp-(q'-q).dri\; 

being  the  same  as  in  [3766],  with  a  slight  alteration  in  the  arrangement  of  the  terms. 


VI.  i.  <^5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  31 

The   second   member  of  this   equation  becomes   nothing,    in  virtue  of  the 
equations  [1089,  1132]  ;  therefore  we  have* 


a  ?t .  d  (5  K  =  0  ; 


[3767] 


hence  we  deduce,  by  observing  that     n"  a^  =  \    [3709']  ,t  [37671 

3dt.fdt.d&R_    3m'.gdt 

m''g  being  the  arbitrary  constant  quantity  added  to  the  integral  fdôR  [1012']. 

It  now  remams  to  consider  the  function „  ,— 1 ,       which 

r-  d  V 

occurs    in  the   expression  of     d&v    [923].       If  we   neglect    the   square   of      [3768'] 

2  S  .  (r  R')    d  t^ 
the   disturbing    force,    this    function    will   be    reduced    to       —     „  ,       — , 

r^  dv 


* 


(2378)    Taking  into  consideration  only  two  bodies,    m,  m',    we   get,   as  in  [1072], 

^=(0,l).?-[irr]./';  ^  =  -(0,l).A+[ôZ].A'.  [3767a] 

Multiplying  the  first  of  these  equations  by     — R/,     the  second  by     dh,     and  adding  the 
products,  we  find,  that  the  sum  of  the  terms  of  the  first  member  vanishes  ;  consequently     [37676] 
the  sum  of  the   terms  in  the  second  member,   being   the  same  as  the   terms  depending 
on     dh,  dl,     in  [3766],  must  also  vanish.      Again,  we  have,  in  [11.31], 

^=(0,1).  (<?'-<?);  ^'__(o,l).(/__p);  [3767.] 

multiplying  these,  respectively,  by  — dq,  dp,  and  taking  the  sum  of  the  products;  the 
first  member  becomes  identically  nothing,  and  the  second  member  is  the  same  as  the  terms  [3767rf] 
depending  on  dp,  dq  [3766],  which  are  therefore  equal  to  nothing,  as  in  [3767]. 
We  may  incidentally  remark,  that  the  quantities  (0,  1),  [Ôj]],  &c.  [3761]  ;  also  dh,  dl,  &ic. 
[1102,  1102ff],  are  of  the  order  m' ;  consequently  the  second  member  of  [3766]  is 
of  the  order  m'^  ;  but  its  integration,  in  [3768],  introduces  divisors  of  the  order 
g>  gi>  ,?î'  ^c.  [1102,  1102«],  which  are  of  the  order  m'  [1097t]  ;  by  this  means,  the  [3767e] 
integral  fdt.àèR  [3768],  is  reduced  to  terms  of  the  order  m,  like  the  other  terms 
computed  in  this  article. 


t  (2.379)    The  integral  of  [-3767],  using  the  constant  g  [1012'],  is  an.fàSR  =  an.m'g; 
lultiplying  this 
we  get  [3768]. 


multiplying  this  by       ,      and  then  dividing  by     r^ d v  z^  a^  n  d  t .  \/ {I  —  è')  [3159},     [3768a] 


32  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

^    „  /dSR\         ,, 

[3769]      or  by  [928,  962],   to       V^ .*  This    quantity    produces, 

m.ndt.a-'.i— — I 
[3769']     in    the    first   place,    the    term       .^-—^  "     ,t       which  is  to  be  added 

?iin'  p'lJ  t  .      ,  .3  m'.  as:  ndt 

[3769"]     to  ,    ';  [3768],    or    to    the   equivalent    expression  /-;— ^     , 

deduced    from       ?r  «^  =  1      [3767'];        and    the    sum    vanishes    by    the 
substitution  of     g  =  —  -^a.l— — j    [1017]. 

Resuming  the  expression  of  ôR  [3764],  we  shall  observe,  that  the  function 

[3771]  I'  .aa'.B^'K{(p'-py+  (ç'-ç)^}  +  &c.î 


*  (2380)     We    have,   in    [3757&,   c],    by    neglecting    tlie    square    of   the    disturbing 

[37690]     force,      2  r  5  iî'  +  R '  5  r  =  2  5  .  (r  iî '  )  =  2  a  .  (jj^)  •      Multiplying  this  by     d  t"-     and 

by     l  =  n^tt^    [376T],    and   then   dividing  by     r^  d  v:^  a~  nd  t  .</{\—e^)    [3759],     we 

2 a^.  I  ——  ).ndt 
[37695]      get        ^  °"  \ [3769],     for  the  corresponding  terra  of    d>]v. 

t  (2381)    The   value  of   R  [957],  or  rather  [1011],  gives,    for  the  case  of    {  =  0, 
[3770a]     and  for  terms  mdependent  of    nt,  n't,     S R  =  I  i7i' .  A'-''\      Substituting  this  in  the  term 

/djKOA 
of    dSv  [37696],  it  becomes  as  in  [3769'].       Now  if  we  substitute      g-=— Ja.(-^j 

[37706]  .  m'.ndt.a^     /rf.^(oi\  ,     ,.     . 

[1017],  in  the  term  of    dêv,  [-3769"],  it  becomes      —  ";,^_^o,  ■\d^)'  '^ 

destroyed  by  the  equal  and  opposite  term  obtained  in  [3769']  ;   so  that  this  sum  becomes 
[3770c]     nothing,  as  in  [3770].      The  calculation  [3767—3770]  is  in  some  respects  a  repetition  of 
that   in  [1016",  &ic.]  ;    and  we  see  that  the  value  of  g,   assumed  in  [1017],  suffices  even 
when  we  notice  the  parts  of   R   contained  in  [3764]. 

%  (2382)    Taking  into  consideration  only  two  bodies     m,  m,     the  differential  of  [3771] 

[37710]     '^'"  ''^      im'.aa.B''\\{p'—p).{dp'—dp)  +  {f/—q).{d(/—dq)l;       observing 

that    B^^^  [956]  is   a  function  of  the  constant  quantities     a,  a'  [1044"].       Now  the  first 

and  second  of  the  equations  [1132]  become  as  in   [3767c],  and  the  third  and  fourth  of  those 

[37716]     equations  give     ^  =— (1,0). (q'—q)  ;      -^  =(1,0) .(/ — p).      Hence  the  differential 

expression  [3771a]  becomes 
[3771c]  ^  ^/ .  „  „'.5(n  .  (p'—p) .  (ç'_  î) .  {—  (1,  0)  — (0, 1)  +  (1,  0)  +  (0,  1)(  .  ^  <  ; 


VI.  i.  >§5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  SS 

is  equal    to   a  constant  quantity  independent  of  the   time    t,    because   its 
differential  becomes  nothing,  in  virtue  of  the  equations  [1132];  and  if  we 
consider  only  two  planets,  m,  m',  as  we  shall  hereafter  do,    (p'—pf+{q'—qT     [^TTr] 
will    l)e  a  quantity  independent  of   the  time,    in  consequence   of  the   same 
equations.         Therefore    the    preceding    function    [3771]    can    produce    in 

^  n  d  t .  a  .{ ) 

'\'i^/     [3769],    only  a  quantity  independent  of   tdt,  kc,  which     [3771] 

.     v/l— e^ 
may  therefore  be  neglected,  since  it  may  be  supposed  to  be  included  in  the 
value  of  ndt.       Hence  we  shall  have,  by  eliminating  the  partial  differentials    [3771"] 
of  A^°^  and  A^'\  relatively  to  a',  by  means  of  their  values  [1003],* 


[3772] 


in  which    the    tenns   between    the   braces  mutually   destroy   each  other,    and  render  this 

quantity  equal  to  nothing  ;  therefore  the  expression  [3771]  must  be  constant,  and  may  be 

represented  by  G,   and  it  will  introduce  into  5  R  [3764]  the  constant  quantity   G.      Now 

as  this  quantity,  considered  as  a  function  of  a,   produces  in  [3771"],  only  a  term  wliich 

may  be    inckided  in  the  expression  of     ndt,     we  may  neglect  it,  and  reject  the  tenn     '■         ' 

depending  on  jB'*   in  [3764]. 

*  (2-383)  It  appears  from  [3752(/],  that  the  coefficients  of  }m'.{P-\-P),  ^m'.{h'^+l'^), 
are  equal  in  the  value  o{  S  R  [3764]  ;  these  terms  may  therefore  be  connected  together, 
as  in  [377*26].  Now  if  we  put  the  two  expressions  of  JV-^'  [3753",  3755'"]  equal  to 
each  other,  then  divide  by    |  m',   we  shall  have,  for  the  case  of  i  =  0, 

-  ^,,,  ,  ^      /dJim\  /(/.4(i)\    ,       ,  /dd.m)\      ^  ^,,,      ^     /dA(.^i\       „  fddJiw\ 

4^'-+2«.(-^)  +  2a'.(— )  +  «a'.(^-^,)=2^«>-2a.(-^)--«^(^;      [3772«] 

substituting  this  in  the  coefficient  of    lm'.{hh'-\- II')    [3764],  it  becomes  as  in  [3772J]  ; 
hence  we  get 

Taking    the    partial   differential    of    this    expression,    relatively    to    a,    and   multiplying    it 
by     2ndt  .a^,     we  get  [3772]. 

TOL.  III.  9 


[37726] 


34  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Ccl. 

Now  if  we  collect  together  all  these  terms,  we  shall  obtain,* 

irof"  ,-  vi'.ndt  C  /dAin\       _       fdd.m\  fdKm\~} 

epend- 


Expres- 
sion of 


[3773] 


[377:%] 


[3774]  In  this  expression  we  may  neglect  the  terms  independent  of  the  time  t  [3773e]. 
Hence  it  is  easy  to  deduce  the  expression  of  (/  h  v',  by  changing  what  relates 
to  m  into  the  corresponding  terms  of  m'  and  the  contrary  ;  and  observing, 

[3775]  that,  though  the  value  of  J^''  [997],  relative  to  the  action  of  m'  upon  m, 
is  different  from  its  value  relative  to  the  action  of  m  upon  m',   yet  we  may 

[3775]     use,  in  the  preceding  expression,  either  of  these  values  at  pleasure.!      But 


*  (2384)    The  value  of   dSv   [3773]  is  found,  by  adding  together  the  several  parts  of 
the  expression  [3757(/],  computed  in  this  article  ;  and  as  tlie  terms  [3768' — 3771"]  destroy 
[3773a]     gj^jjjj  Qfjjgj.^    there  will  remain   only  the   terms   [3762,  3772],    to  be  connected    together. 
The  expi-ession  [3762],  by  the  substitution  of  the  values  of  (0,  1),  [""Til   [1073]   becomes 


and  as  the  factors  without  the  braces  are  the  same  as  in  [3772],  the  sum  of  the  two 
expressions  [3772,  37736]  is  easily  found  to  be  as  in  [3773]  ;  which  is  a  function  of  the 
[3773c]  elements  of  the  orbits  similar  to  that  mentioned  in  [1345'"'].  If  all  the  terms  of  this 
function  were  constant,  they  might  be  included  in  the  expression  of  the  mean  motion  ndt. 
But  e^  =  h^  +  P,  e^  =  h'^-^r^,  he.  [1108,  1109],  are  composed  of  con«to«^  quantities, 
and  of  others  depending  on  the  secular  periodical  variations  of  c,  e,  Stc.  ;  and  it  is  evident, 
that  the  constant  quantities  produce  in  d  5  v  terms  of  the  same  form  as  the  mean  motion  ; 
they  may  therefore  be  neglected,  as  in  [3771'",  3774]. 


[377.3rf] 
[3773e] 


t  (2385)    Substituting  [964]  in  [963'],  and  then  putting    s:=i,    we  get 

[3775a]  (a2_2  „  «'.  cos.  è  +  a'^)-i=a'-K\i  bf  +  i'|>.  cos.  ê  +  if  .  cos.  2é  -f-  &c.^ 

Now  the  first  member  of  this  equation  is  symmetrical  in   a,  a'  ;   tlierefore  its  second  member 

must  also  be  symmetrical  ;  so  that  we  shall  have,  generally,   a'~'.è'f    equal  to  a  synmretrical 

flinction  of   a,  a';  and  if  we  refer  to  the  formulas  [996,  997],  we  shall  see,  that  for  all 

^  '     values  of  i,  except   i=l,  the  function  ^<''  is  likewise  symmetrical.      In  the  case  of  ?  =  1, 


VI.  i.  §5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  35 

we  may  obtain    dov'    more  easily  by  the  following  considerations.      If  we     [3775"] 
add  the  value  of   d^iv,   multiplied  by  w\/â,  to  the  value  of  d!iv',  multiplied 
by   in'\/'a ,   Ave  shall  have,  by  substituting  the  partial  differentials  of  A^^\  A'^\ 
relative  to  «,  instead  of  those  relative  to  a',* 

m\/a.(ISv-{-7nya'.cJov:^ ^ .lh^-{-PJf-h --{-I  ^  .  j^a .  \^-j^ j  +  i  a  .  {^-j^ J  ^ 

[3776] 


corrresponding  to  the  action  of?»'  upon  m,  we  have     ,/2''"  =  -- ;.&      [997];    and  in 

J  "         "  [3775c] 

the  action  of  m   upon  m',   it  becomes      ./2'"=— — ^—-^i  5      hut   we  may  neglect   the 


parts      —,  — :^,     because  they  produce  nothing  in    dSv,   dôv'.      To  prove  this,  we  shall     [3775rf] 

a 
observe,  that  by  noticmg  only  the  part       .4''*=  —  ,     we  shall  get 

/rf./3Ui\         1  /■ddAO)\  /ddJim\ 

1-77-;  =  ^'  [-1^)=^'  l^I^j=^'  [3775.] 

substituting  these   in    [3773],  the   terms  mutually  destroy  each   other  ;    so   that  we  may 

neglect  this  part  of   ./2'^*,  and  for  similar  reasons  we  may  neglect  the  part     ^'''=--,     in     [3775/-] 

computing  the  action  of    m    upon    m',    and   then  the   two  expressions   [3775c]    become 
symmetrical  in    a,  a',  as  in  [3775']. 

*  (2.386)    Multiplying  [3773]  by  tn^a,  and  dividing  the  second  member  by  na^a=^l 
[3709'],  we  get,  by  reducing  the  factors  without  the  braces  to  a  symmetrical  form, 

+.,„,....,.(*-+n.  i^..(r)+^«'-c-^')+"'-r-^)  \ 

Changing  the  elements    m,  a,  v,  h,  I,  he.    into    m',  a,  v',  h',  /',  &c.    and  the  contrary  ; 

which  does  not,  in  the  present  case,  alter  the  values  of  A^°^  or  ^'"   [3775],  we  obtain     [3776t] 

the  expression  of    m' \/a' .dSv'.      The  factors  between  the   braces  corresponding  to  the 

first,  second,  and  third  Imes  of  [3776a],  become,  respectively,  as  in  the   first  members 

of  [3776rf,/,  h],  and  by  means  of  the  expressions  [1003],  they  may  be  reduced  to  the 


36  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3776]     If  we  consider  only  two  planets,   m  and  m',*    the  differential  of  the  second 

f„__„  ,     forms    [3776e,  ^,  i].       In  making  these    reductions,   we  may   use    the    abridged    symbols 
Ad,  Ai,  A.2,  A3  [3755i],  observing,  that  the  index  of  A'^"''  or  .4<"   remains  unchanged; 

^^''^^  a'.(— )  +  J«-.(^  +  «'3.(-^):=|-.4o-^J  +  M2^„+4^,+^,i 

•\.\—QAu—\SA,  —  9A^—A.:,\ 
[3776e]  =  —  5  .^j  —  ^A.2  —  A^; 

l^nn  ,,.(^)+,,'.{'^)  +  ,P.  (^)=2.i-A-^.!+4.i2A+4^,+^,! 

+  l  —  6Ao—l8Ai—9A.,—A3\ 

[377%]  =—4A^  —  5Aç,—  As; 

/(/./3(iA  /rf9.4<')\  /rf3./4''A 

[3776/.]    -.^<"+«'.(— )-^V^.(^-2a'=.(^  =  -.4„+|-.4„-^,|---.|2^,+4^,+^,| 

— 2 . 1  —  6.^0—18^1—9^2—^31 

[3776i]  =  — 5.2o  +  5A  +  -y-. ^2+9^^3  • 

Now  substituting  the  values  corresponding  to  [31~6c,  g,  i]  in  the  value  of    m'^a.  dSv, 
deduced  from  [3776«],  by  the  change  of  the  elements  [37766],  we  get 


„V...«=  i„„..„.(..+r=).|-.„.('/^)-,v...(^-^)-.=.('-^ 


+i„..,.(".-+"').S-5^-+-.C^')+V.'.(^)+..'.('5S')S- 

Adding  together  the  two  expressions  [3776a,  t],   we  obtain   [3776],  observing,   that   in 
this  sum,  the  coefficient  of    h^ -\- P     is  found  to  be  the  same  as  that  of    A'^-j-/'^.       We 

[3776i]      may  remark,  that  the  factor ^ — ,     in  the  second  line  of  [3776],  is  erroneously 

printed '■ in  the  original  work.      If  we  multiply  the  second  member  of  [3776] 

by     ?ia*^l    [3709'],  and  substitute  the  expressions  (0,1),  [ôT\  [1073],  we  shall  get, 
bstead  of  [3776],  the  following  equation  ; 
[3776m]  m^a.d&v+mya'.dôv'=      im\/a  .  dt .  (0,1)  .{h^ -\-P +  h'^ +  1'^) 

—  Zm\/a.dt.  [KI]  •  {h  li  -\-ll'). 

*  (2387)   The  differential  of  the  equation  [3776m],  may  be  put  under  the  following  form; 
d.\m^a.dàv\-m!s/a'Mv']=     Zm^a.dt.\{Q,\).{hdh.-\-ldl)  —  [^.{h'dh  +  rdl)\ 
^^''^''"^  -\-Zms/a.dt.\{0,\).{Kdh:+l'dl')  —  [-^].{hdK^ldV)\. 


VI.  i.  ^5.]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  37 

member  of  this  equation  will  be  nothing,  in  virtue  of  the  equations  [1089]  ; 
therefore  %oe  have,  by  noticing  only  secular  periodical  quantities,  "for  "■ 

0  =  m  s/a.dàv-]r  m'  \/7i  ■  d  <>  v'  ;  [3777] 

which  immediately  gives    d  tS  v\    when   d  o  v   is  knoivn. 

The  value  of  div   is  relative  to  the  angle  formed  by  the  iivo  radii  veclores 
r  and   r  +  dr.       To  obtain  its  value  relative  to  a  fixed  plane,   we  shall      [3778] 
observe,  that  if  we  put    dv^    for  the  projection  of    dv    upon  this  plane,  and 
neglect    the   fourth  power  of  the    inclination  of  the   orbit,    we   shall    find, 
as  in  [925],* 

dv=dv.\\^-ls''—\/^À.  [3770] 

We  have,  as  in  [1051], 

s  =  q.sm.{nt  +  s) — J9.C0S.  (n/  +  j) +  &C.  ;  [3780] 

which  gives  f 


rf5  =  ^j2_^yji.cos.(7t^  +  0  +  (np  +  ^Yf/i.sin.(«^-f3)  +  Sic.  ; 


[3781] 


Substituting,  in  the  first  line  of  the  second  member  of  this  expression,  the  values    d  h,  d  I 

[3767a],  it  vanishes,  because  the  terms  mutually  destroy  each  other.      The  second  line 

of  the  second  member  becomes,  by  the  substitution  of  the  formulas  [1093,  1094],  equal 

to     ^m^n'.dt.\{\,Q).{li'dh'-{-rdl')  —  ['ûV^.{hdh'  +  ldV)\,     which  vanishes  also  by     [37776] 

the  substitution  of     </A'=  {(1,0) . /'— [To]  J} .  J<,      dV=.\—{\,Q).h'-^[']^].h\.dt,     [3777c] 

deduced  from  the  third  and  fourth  of  the  equations  [1089].      This  is  also  evident  from  the 

consideration,  that  the  expression  [3777i]  may  be  derived  from  the  first  line  of  [3777a], 

by  changing  the  elements  relative  to  m  into  those  corresponding  to  m',  and  the  contrary  ;     [3777rf] 

and  as  that  line  is  found  to  vanish  by  the  substitution  of  the  values  of   dh,  dl  [3767 «], 

the    other  will   in   like    manner  vanish   by   the    substitution   of  the   values   of    d  A',    d  I 

[3777c].       Now  the  second   member  of    [3777a]   being  equal   to  nothing,   we  have,   by 

integration,     m \/a.d&v-\- m' s/à .dhv'=Gdt  \     G  being  a  constant  quantity  independent 

of  the  secular  periodical  equations.      This  quantity    Gdt   may  be  supposed,  as  in  [3771'"],     [3777c] 

to  be  connected  with    ndt,  ri'd  t  ;    so  that  by  noticing  only  the  secular  periodical  equations, 

we  may  put  tlie  first  member  of  the  preceding  equation  equal  to  nothing,  as  in   [3777]. 

•  (2388)  The  equation  [925]  maybe  put  under  the  form  di\=dv\/\l-\-s'^ — (T+TIilTrâv 
Developing  this,  and  neglecting  terms  of  the  fourth  degree  in    s   or    ds,    we  get  [3779]. 

t  (2389)    The  differential   of  .9    [.3780],  considering   p,  q,  t    as   variable,  becomes  as 
in  [3781].       The  squares  of  these  expressions,  which  enter  into  the  function   [3779],  are 

VOL.   III.  10 


38  PERTURBATIOiNS  OF  THE  PLANETS.  [Méc.  Cél. 

[37811     hence  we  shall  find,  by  neglecting  the  periodical  quantities  depending  on  n  t , 
and  observing  that    d  v  ■-=  n  d  t,    very  nearly, 

[3782]  dv^^dv-\-}2  .(q  dp  — p  d  q)  ; 

therefore    to    obtain    the    value    of      d5v^,      we    must    add    the    quantity 
[3783]      \.  (qdp  — p  dq)     to  the  preceding  value  of    dàv    [3773]. 

If   we    only   consider    two    planets    m,    m',    we    shall    ha\r,    by    means 
of  [1132,  1130],* 

[3784]       {q('p—pdq)  ■  m\/â+{f/dp'-p'dq').my^=  —  imm'.dt.aa'.B''\\{p'—p)^-lr{q'—qfl  ; 

[3779a]     of  the  order  of  the  terms  computed  in  this  article  [3702'],  and  by  neglecting  terms  of  a 

d  s~ 
higher  order,  we  may  omit,  in     —    [3779],    the  terms  of   dv   [3748]  depending  on  e, 

[37796]     and  put     dvz^ndt,     by  which  means  we  shall  get      d  v^t=:z  dv.\l-\-i  s^ — i-ir — (» 

in  which  we  must  substitute  s,  ds  [3780,  3781].  In  making  these  substitutions,  and 
noticing  the  terms  independent  of  the  sine  and  cosine  of  nt  or  its  multiples,  as  is  done  in 
this  article,  where  the  secular  periodical  terms  only  are  retained,  we  may,  as  in  [3651a],  put 

[3779c]  sin.2  (n  <  +  e)  =  è  ,        cos.^  (n  ^  +  e)  =  i  ,         sin.  (« /■  +  s)  .  cos.  (n  < -f  s)  =0  ; 

then  the  squares  of  [3780,  3781]  will  give,  by  neglecting  dq^,  dp^,  which  are  of  the 
order  of  the  square  of  the  disturbing  forces, 

[3779rf]  i,a_i.(ç2+_p2); 

Substituting  these  in  [3779],  we  get  [3782]. 

*  (2390)  Substituting  the  values  of  dp,  dq,  dp,  dq'  [.3767c,  3771  i]  in  the  first 
members  of  [3784«,  i>],  and  reducing  the  second  expression  by  means  of  [109.3,  1094], 
we  get  the  second  members  [3784o,  c]  ; 

[3784a]  my'a.{qdp  —  pdq)^ms/a.{Q,  \)  .dt  .  \q  ■  [q' —  q) -^  P -(p' —p)\  ; 

[37846]  w'v/«'-  {q'fip'—p'dq')  =  m'y/a.  {1,0)  .  d  t  .\— q'.  {q'—  q)  —p'.  {p'  —  l})\ 

[3784c]  ==^m^a.{(),l).dt.\—  q' .  (7'—  q)  —  p' .  {p'  —  p)\- 

The   sum   of  the   two   equations  [3784f(,  c]   gives  the  value   of  [3784]   under   tlie    form 

[3784c/]     — m^a. [0,1). dt.\{q'  —  qf-j-{p'—p)^];      substituting    (0,1)    [11.30],   and   dividing 

3 
by    na-==l     [3709'],  it  becomes  as  in  the  second  member  of  [3784]. 


VI.  i.  §6.] 


TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y. 


39 


and  the  second  member  of  this  equation  is  equal  to  dt,  multiplied  by 
a  constant  quantity  ;  *  therefore  by  noticing  only  the  secular  periodical 
quantities,  we  shall  have 

0  =  m y'â  .d&v^-^m' sjd .  d^v^  ; 

&  V   and  (5  v^  being  relative  to  the  fixed  plane. 

6.  We  shall  now  consider  the  inequalities  in  the  motion  in  latitude, 
dependinrr  on  the  products  of  the  excentricities  and  inclinations  of  the  orbits. 
For  this  purpose  we  shall  resume  the  third  of  the  equations  [915]  ; 

We  shall  take  for  the  fixed  plane  the  primitive  orbit  of  m,  in  consequence  of 
lohich  we  may  put  2  =  0  in  the  expression  of  (-i— )•  We  shall  have, 
by  [3736—3741],  observing  that     z'  =  r's',\ 

dR 

rf7 


[3784'] 

Tho  Bame 
formula  for 

reduced  to 
the  fixed 
plane. 

[3785] 


r""  1^2— 2r/.cos.(î)'  — i;)+r'2}*' 


[3785'] 

Differ- 
ential 
equation 
for  the 
latitude. 

[3786] 


[3786'] 

[3787] 

[3788] 


*  (2391)    The  differential  of  the  second  member  of  [3784],  being  divided  by    — 'imdt, 
becomes  as  in  |'3771rt],  and  is  therefore  equal  to  nothing,  as  is  shown  in  [3771c]  ;  hence     [3785a] 
we  find,  as  in  [377 ItZ],  that  the  first  member  of  [3784]  is  equal  to     dt,     multiphed  by  a 
constant  quantity    G,   wliich  may  be  neglected  as  in   [377 le]  ;  so  that  by  noticing  only  the 
secular  periodical  equations,  we  shall  have    {qdp—j)dq).m\/a-\-{q'dp' — p'dq').nJ\/a'^zO.      [37854] 
Now  we  have  found,  in  [3782],  that  by  reducing  «  to  a  fixed  plane,  the  value  of  dv  or   dàv 
must  be  augmented  by     ^.{qdp — pdq);     and  in  like  manner,  the  quantity  d^v'    must 
be  increased  by    i.{q'dp' — pdq).       Multiplying  these  by    m\/a,    m'\/a',    respectively,     [3785c] 
and  adding  the  products,  we  get  the  increment  of  the  function  [3777],  or  the  quantity  to  be 
added  to  it,  to  obtain  the  value  of     m  \/a  .  dSv^-^-m'  \/c!  .  d  5  v/.       Now  this  increment 
vanishes  by  means  of  the  equation  [37856]  ;    consequently  the  function  [3777],  varied  in 
this  manner,  becomes  as  in  [3785]. 

t  (2392)    The  latitude  of  the  body    ot',    neglecting  terms  of  the   third  order,  being     ^3737^-] 
represented  by    s ,    and   the  radius   vector  by    r',     we   shall  have,   by  the  principles  of 
orthographic  projection,     2'  =  //,     as   in  [3787].       Now   /  [37366]   being  independent 
of  z,   the  partial  differential  of   H  [3736],  relative  to   z,   becomes 


(àR\  m' 2' 


m'.(z'- 


l(x'- 


^f+iy'-yf+i^'-'-)]^  ' 


[3787a'] 


40  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cèl. 

the  differential  equation  in    z,   will  by  this  means  become* 


[3789] 


0  =  ^  +  n=2.{l  +  3e.cos.  (n^+£  — ^)| 


+ 


m'.  n^  a^.  s 


\ r^  —  2 r  r.  cos.  («'  —  ^)-\-'i'"~\~ 


We  shall  now  putf 
■clR 


[3790]      ('l:^)^M.sin.{?:.(n7— n«  +  /— s)+2ni+^i+iV.sin.^'i'.(n7-nï+/— i)+L|, 


for  the  jiart  of  [3788] 

ffJR 
[3791]  I77 


r-  —  2r r.  cos.  {v'  —  v)-{-  r' -} ] '~ 


depending  on  the  angles    i.(n't — 7it-\-s' — s)-\-2nt    and    i.(7i't — nt-\-;' — s)  ;* 
[-3792]      and  shall  suppose,  that  by  noticing  only  the  inequalities  of  z,  depending  on 

and  if  we  neglect  quantities  of  the  order    s'^,    we  may  reject  tenns  of  the  order    z'~   or    7* 
in  the  denominator;  then,  as  in  [3742^],  we  shall  have 

[3787i]  {x'—  xf  4-  (i/'  —  i/f  +  {z'  —  zf  =  /-a  _  2  r  r'.  cos.  {v  —  v)  +  r' 2  ; 

substituting  this  and    z  :=  0,    z'==r's'    [3786',  3787]  in  [3787a'],  we  get  [3788]. 

We  may  here  remark,  that  the  method  used  in  this  article,  in  finding  the  motion  in 
[3787c]  latitude,  depending  on  terms  of  tlie  order  of  the  product  of  the  excentricity  hy  the  inchnatlon 
of  the  orbit,  is  difTerent  from  tliat  proposed  in  [948],  and  used  in  [1025,  &c.]  in  finding 
the  terms  independent  of  the  excentricity.  This  last  method  may,  however,  be  applied 
without  any  difficulty  to  terms  depending  on  the  excentricity,  and  we  shall  obtain  the  same 
[3787rf]  result  as  in  [3795 — 3797]  ;  as  has  been  shown  by  Mr.  Plana,  in  Vol.  XII,  page  449,  &c. 
of  Zach's  Correspondance  Astronomique,  he. 

*  (2393)    We  have,  by  means  of  [37026,  c,  3700], 

[.3789o]        (A  ?--3=  ,a a'^. { 1  +  3  e  .  cos.  (n  t  +  s—zi)  -f-  &c.  |  =  7i^.  ^1+36.  cos.  (n  t  + 1—  «)  +  &;c.| . 

Substituting  this  in  [3786],  also  the  expression  [3788],  multiphed  by    n'a^=l    [3709'], 
we  get  [3789]. 

t  (2394)    The  reasons  for  assuming  these  forms  are  evident  from  [3704a — 6],  observing 
[3790«]      that  the  object  proposed  at  the  commencement  of  this  book,  is  to  notice  merely  the  terms 
depending  on  the  squares  and  products  of  the  excenlricities  and  inclinations. 


VI.  i.  §6]  TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y.  41 

the  first  power  of  the  inclination  of  the  orbits,  the  part  of  z,    relative  to 
the  angle     i .  {n't  —  n  i  +  s' —  e)  +  nt,     will  be  * 

z=^yaF.  sin.  \ i .  («' t  —  n  t  +  s'  —  s)  +  n  t  +  s  —  n\.  [3793] 

We  then  have,  by  retaining  only  the  terms  depending  on  the  products  of  the 
excentricities  and  inclinations,! 

0=^--—  -\-nrz  +  %rf.€y.aFA  ,.'.,,  ,    ,      ^  ,  ,  [ 

+  n''a\M.ûn.\i.{n't  —  nt-\-i—;)+27it  +  K\ 
+  n'a\N.ûa.\i.(ri!t—nt  +  B'—c)  +  L\  ; 


[3794] 


*  (2395)    Putting,  for  brevity, 

we  shall  have,  for  the  terms  of  s  [1034]  depending  on  iî''~",   the  expression 

F.  \  (?'  —  q)  .  sin.  Tg  —  (y  — ^)  .  COS.  Tal  ;  [3792i] 

substituting  in  this  the  values    p'  — p  ^=  y  .  sin.  n,    g' —  q  =  y  •  cos.  11    [1033],  it  becomes    [37926'] 

Fy  .  {sin.  T3  .  COS.  n  —  cos.  T3  .  sin.  n  j  =  Fy  .  sin.  (  T3  —  n) 

=  F7.  sin.  {i  .  {n'  t—n  t  -J[-  ^—  s)  -\-  n  t -{-E  —  n\.      [3792e] 

Multiplying  this  by    r,    we   get  the  corresponding  part  of   z=^rs    [3787,3796],  to  be     [3792(/] 
substituted   in   the  term      3  n^  e  z  .  cos.  {at -{- s  —  zs)    [3789].       Now  this   term  is  of  the     [3792«] 
second  order,  or  of  the  same  order  as  the  terms  now  under  consideration  [3702']  ;  and  by 
neglecting  tliose  of  a  higher  order,  we  may  substitute  a  for  r,  in  the  expression  of  z  [3792(7], 
and  we  shall  have     z=a«;     hence  the  term  of  s,  computed  in  [3792c],  produces  in  z     [3792/"] 
the  quantity  [3T93].       Substituting  this  in  [3792e],  and  reducing  by  means  of  [18]  Int., 
we  get  the  tenus  depending  on  F  in  [3794].     In  computing  the  value  of  the  term  [3792e], 
and  neglecting  quantities  of  the  order     m'^  or  e^,     it  is  not  necessary  to  notice  any  other 
terms  of  s  [1034],  except  those  depending  on  B'-^'^^  or  F,  which  we  have  used  above.    [3792g-] 
For  the  terms  depending  on  the  arc  of  a  circle  nt,    in  the  second  and  third  lines  of  [1034], 
vanish,  as  in  [1051],  in  consequence  of  the  secular  variations  of  p,  q.       Again,  having 
taken  the  primitive  orbit  of  m    for  the  fixed  plane,  we  have    z  =  0    or    s  =  0    [3786'],  at 
the  commencement  of  the  motion,  corresponding  to    p  =  0,    q^O   [1034,  1032]  ;  so  that 
these  terms  may  be  neglected  in  computing  [3792e].       Lastly,  the  terms  of  s  depending 
on     sin.  {n't  -]-  e),     cos.  («' C -(- s'),     in  the  fourth  line  of  s  [1034],  may  be  considered  as 
included  in  the  term  of    7*3    or   of  F   [3792a],  depending  on     i  =  I  ;     consequently  the     [3792i] 
function  [3792é]    is  rightly   expressed    by  the  terms  depending   on    F    in    [3794]  ;    the 
quantity   F  being  of  the  order   m'   [3792a],  as  well  as  M,  JV  [3790,  3791].  [3792*] 

t  (2396)    The  equation  [3794]  is  easily  deduced  from  [3789]  ;  for  the  two  first  terms 
are  identically  the  same  in  each  ;  the  third  term  depending  on  e,  reduced  as  in  [3792/,  Sic], 
VOL.   III.  11 


[3792A] 


[3795] 


4*2  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

hence  we  get,  by  integration,* 

iin^.ey.aF.sm.\i.(n't  —  nt  +  s'—s)-\-2nt-ir2î—7z—n\  ^ 
._       (  +n''a\M.sm.\i.(n't—nt  +  i—s)-\-2nt-^K\  \ 

\  in'—(i—  l).n\.\  in'—(i—3) .  n  \ 

i%n?.ey.aF.sm.  [i.{n't — nt-\-^' — 0  +  '^ — n|  ) 
\  +n?a^.N  .ûn.\i.{n't—nt-]-s'—i)-\-L\        \ 

\in'  —  (i  +  \).n\.\in'—{i—\).7i\ 
We  have  the  latitude  s,  by  observing  thatf 

s  ^=~  =:--{--  .e  .  COS.  (nt  -\-i  —  ■a)  : 
r         a       a  ^  ^  ' 

therefore  s  may  be  obtained  by  dividing  the  preceding  expression  of  z  by  a, 
and  adding  to  it  the  quantity  % 

ley.F.?.m.{i.{n't—nt-\'S—i)  +  2nt+2t—^  —  T\] 
+  \ey.F.%m.  \i.(n't — nt-\-s — £)  +  «  —  n|. 


[3796] 


[3797] 


[3794o]  produces  the  terms  depending  on  F  [3794]  ;  the  two  remaining  terms,  comprised  in  the 
second  line  of  the  second  member  of  [3789],  are  represented  by  the  fonction  [3791],  or  by 
the  equivalent  expression  [3790]  multiplied  by  7t^a''=l,  as  in  the  two  last  lines  of  [3794]. 

*  (2397)    The  equation  [3794]  is  of  the  same  forai  as  [865a],  putting    y  =  z,  «  =  w; 
[3795o]     then  any  term  of  [3794]  depending  on  F,  M,  or  JV,  being  represented  by  a.K.s\n.  (m^t-\-s), 

[379561     the  corresponding  term  of  z  will  be  represented  by     , ; ,    '"^     ',     'as  in   [871"]  ;    the 

'  X  u  i.  -^       (m,-(-n).(m,  —  n) 

letters  m,,  e,,  being  accented  to  distinguish  them  from  the  similar  letters  of  the  present 
[3795c]     article.      Now  putting    m^:=zi.{^nl — n)-\-2n    in  the  first  and  third  of  ^Aese  ^erm^  of  [3794], 

and  m.i  =  i.{n' — n)  in  the  second  and  fourth,  we  get,  successively,  the  terms  of  z  [3795]  ; 
[3795d]    all  of  which  are  of  the  order  ?«'  [3792Ar]. 

f  (2398)    We  get,  in  like  manner  as  in    [3787],    r5  =  c;     dividing  this  by  r,   or  its 
[3796a]     equivalent    expression     a.\\  —  e.  cos  .  {nt -\-  e  —  ra)}     [3701],    we  get    the    two    values 
of  s  [3796],  neglecting,  in  the  last  of  them,  the  terms  of  the  third  order  in  e  and  z. 

J  (2399)  Substituting,  in  — .e.cos.  (?i<-|-s — ra)  [3796],  the  term  of  z  of  the  first  order  y, 
assumed  in  [3793],  and  reducing  the  product  by  means  of  [18]  Int.,  we  obtain  the 
corresponding  values  [3797].  Adding  these  to  the  term  of  -  [3796],  deduced  from 
[3795],  we  get  the  terms  of  s.  of  the  proposed  forms  and  order.     These  terms  are  neglected 


VI.  i.  §6.] 


TERMS  OF  THE  SECOND  ORDER  IN  e,  e',  y. 


45 


Nothing  more  is  required  but  to  ascertain  the  values  of  M  and  iV;  which 
may  be  easily  found  by  the  analysis  in  §  4.  We  shall,  however,  dispense 
with  this  calculation,  because  the  inequalities  of  this  order  in  latitude  are 
insensible  except  in  the  orbits  of  Jupiter  and  Saturn,  whose  mean  motions 
are  nearly  commensurable,  and  we  shall  give,  in  [3884 — 3888],  a  very 
simple  method  for  the  determination  of  these  inequalities. 

If  we  refer  the  motion  of  m  to  a  fixed  plane,  which  is  but  very  slightly 
inclined  to  that  of  its  primitive  orbit,  putting  tp  for  the  inclination  of  the 
orbit  to  this  plane,  and  a  for  the  longitude  of  its  ascending  node  ;  we  shall 
have  the  reduction  of  the  motion  in  the  orbit  to  this  plane,  by  the  method 
explained  in  Book  II,  ^22  [675,  &c.],* 

—  J-  .  tang."(p .  sin.  (2  v^ —  2  é)  —  tang.  <?) .  J  5  .  cos.  {v^ —  ^)  ; 

»  being  the  motion  v  referred  to  the  fixed  plane.  Hence  the  motion  in 
latitude  produces  in  the  motion  in  longitude,  upon  the  ecliptic,  inequalities 
depending  on    the    squares    and    higher    powers    of    the    excentricities    and 


[3797'] 
[3798] 


[3799] 


[3800] 
[3600'] 


by  the  autlior  in   [3797']  on  account  of  their  smallness.       The  most  important  terms  of  the 
perturbation  in  latitude,  of  the  second  order,  computed  in  [3885, 3886],  are  reduced  to  numbers      [37976] 
in  [4458,  4513],  for  Jupiter  and  Saturn,  in  whose  orbits  these  terms  have  a  sensible  value. 


*  (2400)  In  the  annexed  figure  73,  AB  \s  tlie  primitive  orbit  of  the  planet  rn,  A  G  the 
fixed  plane,  D  the  place  of  the  planet,  B  D=^&s  the  perturbation  in  latitude  now 
under  consideration,  which  is  perpendicular  to  A  B  ;  lastly,  the  arcs  B  G,  D  EF  are 
perpendicular  to  AG,  and  BE  perpendicular 
to  DF.  Then  by  using  the  notation  [669"], 
we  have  AB:=^v  — 13,  AG^=v^ — ê, 
BAG^ip;  and  in  [676'],  by  neglecting  tf^, 
^B=^G'  +  tang.2iç,.sin.(2i;,— 2^)  ;  but 
on  account  of  the  smallness  of  cp,  we  may 
put  tang.3  J  9  =  (  ^  tang.  <p  )^  =  J-  tang.^  «j  ; 
so  that  to  reduce  A B  \o  A  G,  we  must  apply  the  correction  — ^tang.^ip.sin.  (2t), —  26), 
as  in  the  first  term  of  [3800].  Again,  since  B D  is  perpendicular  to  AB,  and  BE 
perpendinijar  to  DF  or  B  G,  we  have  nearly,  the  angle  ABG  =  angle  D  B  E  ; 
moreover,  in  the  spherical  triangle  A  B  G,  we  have  cos.  ABG  =  sin.  BAG  .  cos.  A  G 
[1345*-],  or  in  symbols,  cos.  D5  jB==  sin.  ip  .  cos.  («^  —  d).  Now  in  the  right-angled 
triangle  Bfil>,  we  have,  very  nearly,  BE  =  BD.cos.DBE=iàs  .sm.(p.cos.{v;—ê); 
and  on  account  of  the  smallness  of  p,  we  may  change  sin.cp  into  tang.ç,  also  BE  into  FG; 
hence  F  f?  =  5  s  .  tang.  (?.  cos.  (j;,— Ô).  Subtracting  this  from  AG,  we  get  AF;  and 
in  this  way  we  obtain  the  second  term  of  [3800]. 


i;-« 


[3800a] 

[38006] 

[3800c] 
[3800(/] 

[aSOOe] 
[3800/] 

[3800^] 


44  PERTURBATIONS  OF  THE  PLANETS.       [Méc.  Cél. 

[3800"]  inclinations  of  the  orbits  ;  but  these  inequalities  are  insensible  except  for 
Jupiter  and  Saturn. 

If  we  notice  only  the  secular  quantities,  and  put,  as  in  [1032], 

[3801]  tang.  <p .  sin.  Ô  =p  ;  tang,  ip .  cos.  â  =  ç  ; 

we  shall  have* 

[3802]  is  =  t.~.  sin.  (n  i  +  s)  —  t-'j^  •  cos.  (n  t  +  s). 

[3803]      The  term     —  tang.  (? .  5  5  .  cos.  (v^  —  ê)     produces  the  following  expression, 
[3804]      ^•^9'P~~P    l!  .     so  that  we  shall  havef 

[3805]  V-V  +  t.  —^ , 

which  agrees  with  what  we  have  found  in  the  preceding  article  [3782]. Î 

*  (2401)    If  we  suppose  s  to  be  a  function  of   t,   which  becomes  S,  when    t  =  0,    we 

[3801a]     shall  have,  by  the  theorem  [607,  &c.],     s  =  S  +  t .  (^  —  j  +  —  .  (^— j  +  &ic.       If  we 

neglect  t-  and   the  higlier  powers  of  t,   and  notice  only  the  secular  inequalities,  we  shall 

get    s  —  S=t.(-—-].      Now    s — S,    being  the  variation  of  s  in  the  time  t,  is  what  is 

represented  above  by   &s  ;    hence      S  s  ^^  t .  I j  ;       and  by  noticing  only  the   secular 

inequalities  depending  on    dp,   d  q,    in  [3781],  we  obtain 

/dS\       dq     .     ,  ,       dp  ,        ,     > 

[3801c]  [-j^)  =  -^  ■  sm.  («  t  +  s)  —  ~.  cos.  (n  t  +  s)  ; 

consequently  &s   becomes  as  in  [3802]. 

t  (2402)  Developing  cos.  (v—  è)  by  [24]  Int.,  and  then  substituting  the  values  [3801],  we  get 
[3804a]  —  tang,  (p  .  cos.  (d, —  ^)^  —  tang. (p . \ cos. â . cos. i\-\- sin. Ô . sin . d J  =  —  q  .cos.  i\ — p  . sin. d, 

[38046]  =  —  q. COS. {nt-\-s)— p. sm.{n(-\-s)  ; 

observing,  that  as  this  quantity  is  of  the  order  j},  g,  and  is  to  be  multiplied  by  5s,  in  [3800], 
which  is  also  of  the  same  order  [3802,  3767c],  we  may  put  v^=^nt-\-s,  neglecting,  as  usual, 
the  terms  of  a  higher  order  in   p,  q.      Multiplying  together  the  expressions  [3802,  3804è], 

[3804c]  and  retaining  only  the  quantities  independent  of  the  periodical  angle  2nt-{-2s,  we  may 
use  the  values   [3779c],    and  we  shall    get,  for     — tang,  (p  .  i5  «.  cos.  (r, —  è),      the  same 

[3804rf]  expression  as  in  [3304].  This  represents  the  secular  change  of  v,  arising  from  the  last 
term  of  [3800]  ;  and  by  adding  it  to  v,  it  gives  n,,  as  in  [3805].       We  may  observe,  that 

[3804e]  the  first  term  of  [3800]  produces  no  secular  terms,  or  such  as  are  independent  of  2t', —  2^, 
and  it  is  therefore  neglected  in  this  estimate  of  v,  [3805]. 

[3805a]  t  (2403)  Neglecting  terms  of  the  order    t^   or    m'^,    we  may  suppose    i.{qdp — pdq) 


VI.  i.  §7.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  c',  7.  46 


[3806] 


[3806'] 


ON  THE  INEaUALITIES  DEPENDING   ON  THE  CUBES  AND  PRODUCTS  OF  THREE  DIMENSIONS  OF   THE 
EXCENTRICITIES   AND  INCLINATION'S  OF  THE  ORBITS  AND  THEIR  HIGHER  POWERS. 

7.    The    inequalities    depending    on    the    cubes    and    products    of    three 
dimensions  of  the  excentricities  and  inclinations  of  the  orbits,  are  susceptible    .p„of„,„, 

r    ^  r  u.  of   /i    of 

01  two  lorms,  the  third 

order. 

R  =  M.  sin.  {i  .  (n'  t  —  nt-\-  «' —  s)  +  3  n  ^  +  ^|  ;  [First  form.]  [3807] 

R  =  N.  sin.  {i  .  {n't  —  n  /  +  s' —  s)  +     nt  +  L].  [second  fum,.]  [3807'] 

We  may  determine  them  by  the  analysis  employed  in  the  preceding  articles  ; 
but  as  they  become  sensible  only  when  they  increase  very  slowly,  we  can 
make  use  of  this  circumstance  to  simplify  the  calculation.      We  shall  resume 

2d .  (rS 7-) 
the  expression  [37156],  and  shall  neglect  the  term     — 3'    ,  .    >      which  is      [3808] 

ci   III  (Xi  z 

then  insensible, t  because  of  the  smallness  of  the  coefficient  of  t,  in  the 
inequalities  now  under  consideration.     Then  this  formula  becomes 

àv=  —  '^^^^  +  Sa.ffndt.AR+'2fndt..a\('^^^.X  13809] 

to  be  equal  to   Cdt,    C  being  a  constant  quantity  ;  then  [3782]  becomes    dvp=dv-\-Cdt,     [3805J] 
whose  integral  is    v^=v-\-C t,    as  in  [3805]. 

*  (2404)  The  reason  for  assuming  these  forms  is  evident  from  the  principles  used 
in  [3704a — 6],  For  the  coefficients  of  n't,  — nt,  in  [3807],  are  i,  i — 3,  respectively;  [3807o] 
their  difference  3  expresses  the  order  of  the  coefficient  k  [957"'",  &c.],  or  that  of  M  [3807], 
which  must  therefore  be  of  the  order  e^.  Again,  the  coefficients  of  n' t,  —  nt  [3807'] 
are  i,  i  —  1  ;  their  difference  is  I ,  consequently  N  may  contain  terms  of  the  order  [3807fc] 
1,  3,  5,  fee.  [957'",  fiic.]  ;  which  include  those  of  the  order  (?  ;  and  it  is  evident  from 
[957",  &c.],  that  these  forms  embrace  all  these  terms  of  the  third  order. 


t  (2405)  This  remark  applies  exclusively  to  terms  of  the  form  [3807],  like  those 
in  the  three  first  lines  of  the  second  member  of  [3819],  depending  on  the  angles 
i.{r^  t—nt-\-s'  —  i)  -\-Znt,  whose  differential  introduces  the  very  small  factor  i.(n'  — n)+3n 
[3818(/].  But  this  small  factor  is  not  produced  in  the  differential  of  the  terms  of  the 
form  [3807'],  contained  in  the  last  line  of  the  second  member  [3819]  ;  and  then  the 
term  [3808]  is  not  neglected,  but  is  computed  in  [3822c]. 

X  (2406)  In  the  terms  treated  of  in  §7,  and  depending  on  the  cubes  of  the  excentricities, 
no  quantities  are  finally  retained  except  those  which  have  the  small  divisor  i.{n' — n)-\-3n, 
or  its  powers;  and  as  the  expression  of  5v  [37156]  contains  the  function  2  d .  {r5r), 
divided  by  a^.  ndt  ;  we  must  examine  whether  this  function  contains  the  small  divisor  we 
have  just  mentioned.     Now  by  the  inspection  of  the  value  of  rôr,    or  rather  of  Sr  [1016], 

VOL.  III.  12 


[3808a] 

[38086] 

[3809a] 
[3809i] 


46  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

The  divisor  y'l — e^  [37156]  must  be  neglected  for  greater  accuracy,  as 
in  Book  II,  ^54  or  [3718'].  We  must  also,  by  the  same  article,  ayply  these 
inequalities  to  the  mean  motion  of  the  planet  m,  in  computing  its  elliptical 
motion  [3720].      This  being  premised,  if  we  suppose 

R  zzz:      m!  P.  sin.  \i .  (n!t  —  nt -\-s'—^)  +  3nf +  3-=! 

[3810] 

+  m' F.  cos. {i .{n't  —  nt-{-z'—i)-\-Snt  +  Si\; 

which  comprises  all  the  terms  of  R,  where  the  coefficient  of  nt   is  greater 
[3811]      or  less  than  that  of  n't  by  the  number  3  ;  we  shall  get,  as  in  [1209],* 

3.(3  —  i).m'n^.a 


[3809rf] 


[38126] 


3a.ffndt.aR-. 


|i.(ra'— ?^)-j-3n}2 


;„,  ,  2(/P  3ddP'  ).,.,,  ,    ,      V   ,  „       ,  „  , 

r»ûioi  I       -j r*  +  (•■  ,  , ,  I  „    >    ., — TT-r-, ,  ,  „    )^  ,  „>.Bm.]i\nt—nt-\-s—s)-\rmt-\-3i\ 

\_mii\  1        ^  \i.(n'—n)-\-3n\.dt        \i.(n—n)->ç-3n\^.dt^S 

in  2dP'  3rfrfP  )  ,.  ,  ,  ,    ,      ,,„      ,„, 

[  {%.[n'—n)-{-Qn\.dt        {i.(n'—n)-\-Qn\Kdt^S  ■ 

we  shall  not  find,  in  the  preceding  function,  any  term  depending  on  the  first  power  of  e, 
[3809c]  and  having  the  divisor  i.[n  —  »t)-j-3n.  In  quantities  of  the  second  order  in  e,  c', 
given  in  [3711,  3714],  we  find  such  terms  having  the  first  power  of  that  divisor  ;  but  these 
terms  depend  upon  angles  of  the  form  i .  {n't  —  n  t  -\- ^ —  s)-\-2nt ,  which  are  different 
from  those  under  consideration  in  this  article  [3806' — 3807']  ;  so  that  they  may  be 
neglected.  To  investigate  the  similar  terms  of  the  order  e',  which  depend  on  the  angle 
i.{n't  —  n  t -\- e' — s)-\-3  nt,  we  may  go  through  a  calculation  similar  to  that  in 
[3703—3714],  changing,  however,  the  angle  i  .  [n' t  —  nt-\-s' — t)-\-2nt  into 
i.(n't — nt-\-s'  —  s)-\-3n't;  which  is  the  same  as  to  increase  the  integral  ntimher  2 — ;", 
connected  with  nt  by  unity;  by  which  means  the  divisors  in-{-{\ — i)  .n,  in'-\-{2 — i).n, 
in' -{-{3 — i).n,  which  occur  in  [3705,3710,3711,3714],  are  changed,  respectively, 
into  î»'  +  (2  —  i).n,  in'-\-{3  —  i).n,  iw'-j-(4  —  i).n.  Hence  the  quantity  r^r, 
[3809e]  similar  to  [3711],  will  contain  a  term  of  the  order  t^,  depending  on  the  form  [3807],  and 
having  for  divisor  the  first potver  of  the  small  quantity  in'-\-  {3  —  i)  .7i ,  as  is  hereafter 
found  in  [3819];  but  this  divisor  will  vanish  from  the  dilTerential  d.[r6r);  therefore  it 
may  be  neglected,  as  in  [3809rt]  ;  and  then  the  formula  [37156]  becomes  as  in  [3809]  ; 
omitting  the  divisor,   \/{l  —  e^),   for  the  reasons  given  in  [3718']. 

*    (2407)      Substituting,    in    the    first    member    of   [1209],    the    assumed    value    of 
[:3812o]     k.sm.{i'n't — int-\-^)    [1208^'],  it  becomes 

ffan^.dt^.\q.sm.{i'n't  —  int-'ri's'—ie)-\-q.cos.{i'n't  —  int-{-i's'—is)\  = 

riia.ain.(i'n't  —  int+i's'—i£)  (j       ^   ,  2dQ'  ,  3rf3Q Ad^q ^     ^ 


^)  ^_o  

(i'n'  —  inf  'i       ^~'~  {i'n'—in).dt~'' (i'n'—inf.dt^       [i'n'—inf.dfi 

i.(i'n't  —  int  +  i'e'—{e)  ^_      _        2rfQ  3rf2Q-  jd^q 

(i'n'—inf  'I      ^       {i'n'—in).dt'{i'n'—inf.dVi'^(i'n'—inf.dt3~ 


VI.  i.  §7.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  y.  47 

Then  we  shall  have  * 

2m'n 


^     ,       „  /dR\  2m 

2.rndt.a-.('—)  =  —  ^--. —  ,  ,„    -. 


«2.  f'^JLYcos.{i.{n't-nt+e-s)-^3nt-\-3sl 
-a".  ('^^)-sin.  {L{n't-nt+^-s)-\-3nt-\-3i] 

Lastly,  we  shall  suppose,  that  by  noticing  only  the  angle 

i .  (n't  —  nt  +  s  —  '.)-{-2nt  +  2B,  ' 


[3813] 


we  havef 

r  S  r 


=  H.  COS. {i .  (n't  —  nt  +  B'—s)-}-2nt  +  2B-\-Al;  [3814] 


Now  if  we  take  the  difierential  of  [3810],  relatively  to  d,  then  multiply  it  by     3  a  .7idt, 
and    prefix    the    double    sign    of    integration,     we    shall     get,     by    using    for    brevity, 

T=n't  —  nt  +  £'—  1    [3702a], 


[3812e] 


C  —  3.{3  —  {).m'.P'.sm.(iT+3nt-\-3i))  ^„^,„,, 

■'■'  •'•'  ^+ 3.  (3  — i)  .m'.P.cos.(îT+3n!:  +  3£)S 

The  second  member  of  this  expression  is  of  the  same  form  as  the  first  member  of  [38126], 
as  is  easily  perceived  by  changing,  in  [3812J],  i'  into  i,  and  i  into  i — 3;  also 
putting  Q  =  —  3  .  (  3  —  z  )  .  m'.  P',  Q'  =  3  .  (  3  —  i)  m'.  P  ;  then  making  the  same  [3812<] 
changes  in  the  second  member  of  [3812è],  we  obtain  for  3a  .ffn  dt .  àR,  the  same 
expression  as  in  [3812].  We  may  observe,  as  in  [3714cZ'],  that  the  secular  variations  of  [3812/] 
the  elements  are  noticed  by  the  introduction  of  the  differentials  dP,  dP',  ddP,  ddP', 
which  are  computed  in  [4415,  &c.,  4484,  &c.]. 

*  (2408)    The  partial  differential  of  R  [3810],  taken  relatively  to  a,  being  multiplied,     [3813a] 
by    2/1  dt .  a^,    and  then  integrated,  gives  [3813]. 

t  (2409)    The  expression  [3814]   is  equivalent  to  that  in  [3711];    if  being  taken  for 
the  coefficient  of  any  one  of  the  terms  of  this  formula,  and   A   representing  that  one  of  the      [3814a] 
quantities     — 2  in,    — «  —  ra',    K — 2  s,      which   is  connected  with  this  coefficient  H  ;     ^001411 
observing  that    H  is  of  the  second  dimension  in    e,  e'.       The  differential  of  [3701],  is 
dr=^ae.ndt.sm.{nt-^E  —  «) -|- &:c.  ;      multiplying  this  by  [3814],    and  neglecting      [3814c] 
terms  of  the  fourth  order,  we  get,  by  using  T  [3812c], 

^-^  .dr^        Hae  .ndt  .cos.{i  T-\-2nt -\-2  s -{- A)  .sin.  {nt-{-B  —  ts) 

=      lHae.ndt.sin.{iT-\-3nt-{-3s—-a-{-A)  [3814d] 

—  i  Ha  e.nd  t  .s'm.  {iT-}-     nt-{-     s -\- zs -\- A). 

As  this  is  of  the  third  order  [38146],  we  may,  in  the  first  member,  put    r=  a,    and  then 
dividing  by     —  andt,     we  get 

'^'•^'       -|ffe.sin.(iT+3n<+3E-^  +  ^)  [3814,] 


(findt 

+  iiîe.sin.  (iT-f     ««-(-    t-^-a  +  A). 


48  PERTURBATIONS  OF  THE  PLANETS.  [Méc  Ctl. 

[3814]  ^  ^*'^"S  determined  as  in  [3814a],  and  having  the  very  small  divisor 
r.  (n'— w) +3n  ;  then  the  first  term  of  ôv  [3809]  gives  the  following 
expression  ; 

[3815]  __^Ll_!  ^_i/fe.sin.|z.  (ra'i  — «f  +  s'  — f)  +  3»i  +  3s  — a  +  Jj. 

Hence    we    shall    find,    by    noticing   only    terms    which    have    the    divisor 

[3816]      i  .  {n' — w)  +  3w,* 

SC    _,              Sa.rfP  3a.ddP'  ■)    .     C{.{n't-nt+i'-s)') 

i             {t.{n'-,i)i-3n].dt      \i.(n'-n)-+-3n]-2.dPS         l+3nt~\-3s         S 
5    p  2a. dP'  3a.  ddP  }         C{.{n't-nt+;'-s)-) 


'—UP- 


•COS. 


Ter  mi  of 


\i.{n'-n)-l-3n].dt      \i.{n'-n)-\-3nl'i.df^S         (+3n«+3e 

<5«  (      a^. (~). COS. U.  (n't  — 7it  +  s' — s)  +  Snt-\-3s\ 

heihird  2m'n  y  \da/  '      ^  '  '   '  '        * 

i.(n' — n)-|-3n    ]  /dP'\ 

/ — a'^.f^j.sin.  \i.{n't — nt-\-s' — E)  +  3n<+3£} 

—  3  Ue.sin.  \i.{n't—nt^^—s)-\-Znt-{-Ze—vi-[-A\. 
The  differential  equation  [3699] 


[3818] 


o  =  ^'  +  '-^  +  Vaie+..Q.t 


The  first  term  of  the  second  member  is  the  same  as  in  [3815]  ;  the  second  term  is  noticed 

r'î8l4/'l     *"  [3822rf].      We  may  observe,  that  it  is  not  necessaiy  to  notice  terms  of  the  order  t^ 

in  dr  [3814c],  because  they  depend  on  the  elliptical  motion,  and   have  no  divisor  of  the 

form     i .  (n' — ?i) -j- 3  ?!  ;     moreover  they  must  be  multiplied  by  terms  of  the  order  e, 

[3814^]     which  occur  in    —   [1023],  to  produce  terms  of  the  third  order  now  under  consideration  ; 

and  these  terms  of  [1023]  do  not  contain  the  small  divisor  just  mentioned. 

*  (2410)    Substituting,  in  the  expression  of   i5i;  [3809],  the  values  of  the  terms  in  its 
[3816a]      ^^^^^^^  member,  given  in  [3815,  3812,  3813],  we  get  [3817]. 

f  (2411)    The  expression  [3818]  is  the  same  as  [3699],  from  which  we  have  deduced 
[3702],  and  by  using  [3705a],  it  becomes 

[3818a]      0==^^^'  +  n^r5?-4-^3«2a.5r.[e.cos.(n<+j-rt)+e2.cos.2.(«)'4-E-^)]+2rd/î+a.('^y^. 

This  is  solved  as  in  [3711&,  c],  and  if  any  term  of  the  expression  between  the  braces  be 

[3818o']     represented,    as    in    [37116],    by      aif.  sin.  (?»,< -}- «,)>      or      o.K  .cos.  {mt  -\- s^),      the 

corresponding  terms  of  rhr  [3711c]  will  contain  the  divisor  m^  —  n^,  or  rather  the  two  divisors 

(m.-\-n),  {m^ — n).     To  find  the  values  of  m^  producing  the  divisor   i.{n' — n)-|-3n  [3818'], 


VI.  i.  §7.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e\  y.  49 

gives,  by  noticing  only  the  terms  which  have  tlie  divisor     i.(n' — n)-{-3ii,      [3818'] 
2.{{~3).mn     (      aP  .sm.  \i.{n't—nt  i-s'  —  i)^3nt-\-Ss\  ■) 


J- (5  )• 
a 


i  .  («'—«)  +3  11  '  I  -JraP'.cos.\i.{nt  —  nt-\-!'—s)-\-3nt  +  3;l  ^ 
—  ^He. COS.  \i. (n't— nt  +  s—s)-^3nt  +  3s—^  + A} 

+  iHe.cos.{i.(n't—7it  +  s—s)  +  nt  +  s  +  ^  +  Al. 


[3819] 

Terms  of 

ri)r. 


we  shall  put  it  successively  equal  to  ???,  +  n  and  m,  —  n  ;  and  we  shall  get 
m,=  2.((i' — «)-)-2n,  'm^=i.[i\! — n)-\-An',  but  we  may  neglect  the  last,  because 
the  coefficients  of  n,  n  dilfer  by  4,  and  the  terms  depending  on  it  must  be  of  the  fourth 
dimension  in  c,  e'  [3704n',  &lc.],  which  are  here  neglected.  Therefore,  in  finding  r5r, 
we  need  notice  only  the  following  terms.  First.  Where  m.^  =  i  .  [n'  —  n)  -(-  2  n . 
Secoii'l.    Where  the  quantity    R,    or  rather  fdR,    contains  the  divisor    i  .  [n' — ?i) -j- 3  w 

[3813'].      Hence  it  is  evident,  that  we  may  neglect     a  .  (— — j,     which  produces  no  such 

terms.      The  part  of  R,  given  in  [3810],  produces  in    2/d  R,    the  following  terms, 


-2.(i  — 3).m'.?i     ( 
77(7i'— n)  +  3V  ■  ^ 


[3818fc] 


[3818c] 


and     [3818rfl 


P.sm.{i.{nt  —  nt-\-s'—e)-{-3nt-\-3s]  ) 
+  P'.cos.f/.(n'<— ni  +  s'— s)4-3  7i<  +  3£|  V 

These  come  under  the  second  form  [38186],  in  which  o-K  has  the  divisor  i.{n' — n)-\-3n. 
The  part  of  rSr  [3818a"],  depending  on  these  terms,  is  found  by  dividing  them  by 
jn/ —  )i^  ;  ?H,  being  in  this  case  equal  to  i  .  {ii  —  n)  -j-  3  ?i  ;  and  by  hypothesis  it  is  very 
small  in  comparison   with   n.      Thus,  for  Jupiter  and  Saturn,  where    i=5,    it  becomes 

m^=i.(n'  —  «) -l-3?(  =  .5  w' — 2n^=j\n    [3711/];    so  that  m,^  is  less  than     ~7^, 

for  the  divisor  m^ — n^,  we  may  write  simply  — 71^=^  —  a~^  [3709'].  Therefore,  by 
multiplying  [3818c],  by    — a^,    we  get  the   part  of    rSr    corresponding  to  these  terms 

of  2/d  R  ;    and  then  dividing  this  result  by  a^,  we  obtain  the  corresponding  terms  of 

The  terms   thus  computed   agree  with  those  in  [3819],  depending  on   P,  P'. 

necessary  to  notice  the  terms  of    2/d  R,    like  those  depending  on   [3703,  3704],  because 

terms   depending    on   different    angles    from   those    proposed 

in  [3807,  3807'],  or  else  such  as  have  not  the  small  divisor  mentioned  in  [3818']. 
The  next  term  of  ajBT  [3818a'J,  which  we  shall  notice,  is  that  depending  on  the  quantity 
Sn^a.ôr  .t^.  cos.  2  .  (?i  i  -f  s  —  ra)  [3818rt]  ;  and  as  we  retain  merely  the  terms  of  the  [3818/] 
third  dimension  in  e,  e',  &:c.,  it  will  only  be  necessary  to  notice  terms  of  the  first  dimension 
in  6r.  Now  if  we  examine  [1023],  we  shall  find,  that  none  of  its  terms,  of  that  order, 
have  the  small  divisor  [3818'];  therefore  we  may  neglect  this  part,  and  then  the  only 
remaining  quantity  in  [3818a],  producing  terms  of  a  ^,  is  Sn^a.Ar  .e  .cos. {nt -\- e  —  ts). 
As  this  contains  the  factor  e,  we  may  notice  in  o  r  only  terms  of  the  second  dimension,  in  [3818^] 
VOL.  III.  13 


rSr 
It  is  not 


[3818f] 


they  will   produce  in     — 


50  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

Adding  this  expression  to  that  in  [3814], 

[3620]  '-Jl^ff^cos.{i.(n't  —  nt  +  i'—^)  +  2nt  +  2s  +  A], 

or 

we  obtain* 

To^r^sof  sr^      H  .cos.li.(n't  —  nt-^e'—s)-i-2nt  +  2^  +  Al 


[3821] 


—  He.cos.{i.(n't—nt  +  i'—^)  +  Snt  +  3s—^  +  Al 

-irHe.cos.{i.(7i't—nt  +  s—B)-{-nti-s  +  z:  +  A\ 

2.(1— S). m  n     (       aP.sm.\i.{n't  —  nt+s'—i)-\-3nt-\-3sl 
'^  i.{7i'—n)-i-3n' i  +  aP'. COS. {i. {n't  — iit-^-s'—sJ-^-Snt-^Qs] 


order  to  procure  those  of  the  third  dimension,  which  are  the  only  ones  investigated  in  this 
article.  The  terms  of  the  second  dimension,  which  can  produce  the  angles  proposed 
in  [.3807,  3807'],  are  evidently  included  in  the  form  [3814]  or  [3820]  ;  multiplying  this 
by     3n^o^.  e  .  cos.  (?i<  +  ^ — «)>     and  reducing  by  [20]  Int.,  it  becomes 

r  „       „  „Ç     cosAi.{n't—nt-{-s'—s)-\-3nt-{-3s-zs-\-A\} 

[3818A]     3n^a.ôr.e.cos.{nt  +  e-^)  X  a=^^''-''''-l  +  cos.li.{n't-nt  +  s'-s)  +  nt+s+^+A\    V 

Now    He    [3814t]    is    of  the   third   dimension   in    c,  e',   he,    and  by  neglecting  higher 

dimensions,  we  may  put     -  =  1   [3701],   and  then  we  shall  have  for  the  remaining  terms 

of  o.K.cos.{m,t  +  e,)    [3818n], 

&He.7i^a'^.cos.ii.(nt—nt-\-s  —  s)-\-3nt-\-3e—Ts+Al 
[3818i]  z  ( 

-Jf-îHe.n^a^.cos.{i.{n't—7it  +  ^—c)  +  nti-B-J^zi-\-.^. 

Dividing  this  by  m^ — n^  [3Sl8a"],  we  get  the  corresponding  terms  of  rSr.  Now  for  the 
first  of  these  angles  i.{n't—nt-{-s  —  £)^3nt-lrSs—zi-\-A,  we  have  OT,=i.(n'— n)  +  3M, 
and  as  this  is  very  small  [3818rf],  it  may  be  neglected  ;  and  then  the  divisor  becomes  — n^- 
[3818A:]  In  the  second  angle  [3S18i],  the  value  of  7«,  is  i.{n' — n)+n  or  \i.{n' — ?(.)+3n} — 2ra, 
which  is  nearly  equal  to  — 2n  ;  hence  m^ — n^  is  nearly  Sn^;  consequently  this  divisor 
is  nearly  equal  to  3n^-  Therefore  if  we  divide  these  terms  of  [3818i]  by  — Ji^  and  3n^, 
respectively,  we  shall  obtain  the  corresponding  terms  of   r  S  r  ;    lastly,  dividing  these  result» 

by  a^,  we  get  the  terms  of    —5-    depending  on  He,  as  in  [3819]. 


[38180 


*  (2412)     None  of  the  terms  of    ^    or    — ,      of  the  order    m'e,     contain  the  small 


a-  a 


divisor  [3818'],  as  is  evident  from  the  inspection  of  the  formula  [1016]  ;  so  that  the  terms 
of  — ,  containing  this  divisor,  and  which  must  be  noticed,  are  Included  in  the  functions  of 
the  second  members  of  [3819,  3320].      Adding  these  quantities  together,  and  multiplying 


VI.  i.  §7.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  y.  51 

This  value  of    —     produces  in    2  v,    an  inequality  depending  on   the   angle      [3822] 

i .  (7i' t  —  nt-\-;'  —  e)  +  n f  +  f,     which  has     i.(n' —  n)-\-Sn     for  a  divisor.     [3822^ 
To  determine   it,   we    shall   resume    the    expression  of    (5  v,    given    by  the 

formula  [931].*      The  part    —    \      , ' —     of  this  expression  produces    [3822"] 

It     m    1i  Or    V 

in    (5  V    the  term 

6v  =  ^  He  .  s'm.[i .  (n't  —  nt-\-  s' —  e)  +  ^  î  +  ^  +«  +  -<4 }  ;  [3823] 

which  is  the  only  one  of  this  kind  having  the  divisor      i  .  (n' — n)-}-3n. 
The  inequality  of  i5î)  depending  on  the  angle    i.(n't — nt-\-s' — B)~\-2nt-\-2s,      [3824] 
noticing    only    the    terms    having    the    divisor     i .  (n' — «)-}-3n,      is,    by 
[3715,  3814],  very  nearly  equal  to 

2H.s\n.{i.(n't—nt  +  B'—B)+2nt  +  2e  +  Al.  [3825] 

their  sum  by     -,     which,  by  [3701],  is  equal  to     l-\- e  .cos.  {nt -\- e—zs) -j-kc.,     we     [38216] 

Of 

get  the  coiTesponding  temis  of     — .      The  quantities  produced  by  this  multiplication   are 

equal    to  the  sum  of  the  terms    [3819,  3820],    with    the    additional    term  produced   by 
multiplying  the  Rinction   [3820J  by     e  .  cos.  {nt-\-  s  —  «),     and  this  term  is 

He.  COS.  {nt-{-e  —  w)  .cos.  \i.{n' t  —  nt-{-s'  —  s)  -f  2  n  i  +  2  e  -f  .4| ,  [3821c] 

which,  by  [23]  Int.,  becomes 

iHe.  cos.  \i  .{lit  —  nt-^s' —  s)  +  3  n  i  +  3  s  —  ts  +  A] 

-\-^  He.  COS.  {i.{nt  —  nt-\-s'—2)  -{- 7i  t -^  s -{- vs -}- jl] . 

Connecting  this  with   the    other    terms    [3819,   3820],    we    obtain,    by    reduction,    the 

function     —     [3821]. 


[3821d] 


* 


(2413)    This  formula,  by  the  substitution  of  [3715a,  3705a],  becomes  as  in  [37156], 


the  part  mentioned  in  [3822"]  being  represented  by     — '—  .       Now  the  last     [3822o] 

a^.  ndt         <fi.  ndt 

term  of  the  second  member  of  [3819]   depends  on  the  angle      i  T -\- n  i  -{- s -\- is -{- A 

[3702a],  mentioned  in  [3822'],  and  if  we  substitute  it  in  the  first  term  of  the  preceding 

2d.{rûr)        .  ,  , 

expression        „   -~— ,     it  produces  the  tenn 
*  a-. ndt  ^ 

—  \i.  {n  —  n)+7i].-^.  sin.  \i  T-|-  n  <  +  e  +  w  +  ^  f  ;  [382261 

and   as  we  have,   very   nearly,      — \i.{n' — n)-\-n]  =2n     [3818Ar]  ;      it  becomes 
2He  .  sin.  \i  T -\-nt  -\- -a -\- A).      Again,  the  second  term  of  [3822a]  has  already  been 
computed  in  [.3814e],  and  contains  the   quantity       i  He  .sm.{i  T-\~nl-\-s-{-zi -\-A)  ;    [3822rf] 
connecting  this  with  the  preceding  [3822c],  the  sum  becomes  as  in  [3823]. 


52  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

Therefore,  if  we  denote  this  inequality  by 

[3826]  K.sm.{i.(n't—nt  +  i'—s)-\-27it+2B-{-B}* 

Terras  of    weshallhave,  in    6v,    the  following  expression, 

ÔV. 

[3827]  i<v  =  ^Jï^e.sia.{i.(n't—nt-JrB'—s)-j-nt  +  B-Jr^  +  B\. 

8.    //  is  chiefly  in  the  theory  of  Jupiter  and  Saturn  that  these  different 
inequalities  are  sensible.      If  we  suppose    i  =^  5,    the  function 

[3828]  i  .  («'—  ?i)  +  3  n  =  5  n'  —  2  n , 

becomes  very  small  [381 8rf],  in  consequence  of  the  nearly  commensurable 
ratio  which  obtains  between  the  mean  motions  of  these  planets  ;  and  from 
this  cause  the  corresponding  terms  of  or,  ov  acquire  great  values.  To 
determine  them,  we  shall  resume  the  expression  of  R  [3742].     The  partf 

[3829]       — .cos.(y— f) -j-\cos.{v'—v)  —  cos.{v'+v)\+-^.— ^ ^, 

^  4      r^  4        J,-2-2r)-'.cos.(y'-«;)-fr'2p 

*  (2414)    The  parts  of  R  [957,  1011],  represented  by  M,  JV  [3703,  3704],  do  not 
contain   the  small  divisor     i  .  {71 — n)-\-3n,     as  is  evident  from   inspection.      Moreover, 

[3826a]     F,   G,  H  [3706],  being  the  parts  of    —     [1016],    depending  on  terms  of  the  first  degree 

in  e,  e,  do  not  contain  this  divisor,  as  appears  by  the  inspection  of  [1016].     Therefore  no  part 

2rf.(?"(5r) 

of    ÔV  [3715],  except  the  first  term      —^^ — 7—,     contains  this  divisor  ;   and  if  we  substitute 

a^.ndt 

in  this  term  the  value  of    r  (5  ?•    [3814],  we  shall  obtain,  in    ô  v,    tlie  terra 

2 

[38266]  .li.{n'—7i)-{-2nl.H.sm.li.{n'i—7it-\-e'—s)-J[-2nt-{'S-j-A}  ; 

substituting  — \i.{7i' — ?))-(- 2  «}=?i  [3S22c],  it  becomes  as  in  [3825].  If  we  now 
compare  the  expressions  [3825,  3823],  we  find,  that  [3823]  may  be  derived  from  [3825] 
[3826c]  by  multiplying  its  coefficient  by  |e,  and  decreasing  the  argument  by  nt-^B  —  sj. 
The  same  process  of  derivation  being  used  upon  the  assumed  form  [3826],  produces  the 
expression  [3827]  ;  which  is  computed  in  [4439]  for  Jupiter,  by  tliis  very  simple  process. 

t  (2415)    We  shall  suppose,  as  in  [1009,  956c,  963'',  1018a],  for  tlie  sake  of  brevity, 
[3829a]  r    =a(l  +  Mj;  r'     =a'.(l+j«;);        v  =^nt  +  s-\- v,  ;       v'=n't  +  s'-^- v,' ; 

[-38296]  a^  =  a  m,  ;  a'     =  a'  w/  ;  a"=:  v,'  —  r,  ;  a.  ^  -  ; 

[38296']  T  ^n't-nt-\-^—e;       dT^{n'—n).dt; 

[3829c)  W=nt-\-B  —  -ro  ;  W'=^n't-\-B'  —  -a; 

[38S9e']  M,,    «/    v'  —  »     are  of  the  order  of  the  excentrlcities,  and    a    is  changed   into    a^,    to 


VI.  i.  §8.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  y.  63 

produces  no  term  of  the  third  order  of  the  excentricities  and  inclinations,      [3830] 

distinguish  it  from  a  [963'^].     If  we  represent  the  function  [3829]  by  m,  and  suppose  U  to 

be  the  part  of  this  value  independent  of  u,,  «/,  f,,  vj,  we  shall  have   U  as  in  [3829/];     [3829d] 

observing  that  the  last  term  of  [3829J  becomes  in  this  case,  by  using  [3744,  3749], 

im'.'j^.aci'.cos.T.la^-2ad.cos.T+a'^l~^  =  ^^m'.f.  ad.  cos.T  .is .  B''\cos.iT 

=  im'.f.aa'.iS.B"Kcos.{i-\-l).T 

=  1  m'.  y^.  a  a'. -2.  B^'-il.  cos.  i  T  ;  t3829e] 


[3829/] 


[3829g:] 


U=L  — ^g- .  cos.  T  —  T  ™''  7*-  "7^  ■  cos.  T  -j-  i  '«'•  y®-  -^  •  cos.  [n  t -\- n  t  -\- ^  -{- 1) 

+  I  m.  f.  aa'.S..  B^-^\  cos.  i  T  ; 

i  being  as  in  [3715'].      The  development  of  u,  as  far  as  the  second  powers  of  aj,  a',  a" 
being  found  as  in  [957e],  is 

«= -■+-(^) +-•  O +^"-  © +H.'.  (^)+^..^'.  G^.) 

the  tenns  of  the  third  order,  obtained  in  the  same  manner,  are 

+i-^"'G-S^)+--^"-G-i^)H-*-'-(^)- 

We  have  given  this  full  development  of  îi,  because  it  will  hereafter  be  of  use  in  the  notes  on 

this  article  ;  and  for  the  same  purpose,  we  shall  also  insert  the  following  expressions,  deduced      [3829t] 

from  the  comparison  of  the  values  of  ao,  a',  a"  [3829J,  a]  with  [659,  668,  669]  ; 

ao  =  rt  .|i  e^  —  (e  — f  e') .  cos.  fV  —  i  e^.cos.  2W  —  i  e^.  cos.  3Wl=au/,  [3829*] 

a'=a'.|Je'2— (e'— tc'3).cos.  fP— ^  e'2.cos.2  JF'  — §  e'^.  cos.  3  ^'}  =  «'m/ ;  [3829i] 

"■~^-(2e-ie3).sin.  fF-Je2.sin.2?r-ife3.sin.3^FS^"''~''''  ^^^^^ 

From  these  values  it  appears,  by  a  slight  exammation,  that  none  of  the  terms  of  U  [3829/] 
produce  quantities  of  the  third  order,  depending  on  the  angle     5  7i'i  —  2nt,     now  under 
consideration.      For  the  terms  of  [3829/],  multiplied  by  y%  of  the  second  order,  depend     [3829«] 
on  the  angles     T,    n'  <  -f  n  <  +  s'  -f  s ,    i  T  ;    and  when  we  combine  these  with  terms  of  the 
VOL.  III.  14 


64 


PERTURBATIONS  OF  THE  PLANETS. 


[Méc.  Cél. 


Value  of 

R 

for  tliis 
case. 

[3831] 


[3832] 


depending  on  the  angle     5  n't  —  2nt;     such  terms  can  therefore  only  arise 
from  the  remaining  part* 

m'.y^  rr'.cos.{v'-\-v) 


R 


^j.2 — ,2;-/.  COS.  (j;' v)  -\- 


JSfS 


I r^ —  2 r r'.  cos.  (ti'  —  v)-\-r'^l- 


and  then  the  expressions  of  P  and  P'  [3810]  will  be  the  same,  whether 
we  consider  the  action  of  m'  on  m,  or  that  of  m  on  m'.  We  shall  now 
investigate  these  values  of  P,  P'. 


[3829o] 


[3831a] 
[3831o'] 

[38315] 

[38316'] 


[3S31c] 
[3831d] 
[3831e] 


[3831e'] 


[3831/] 


^w<  order  in  a,,,  a',  a"  [38297i: — ?»],  they  will  not  produce  the  angle  bn't — '^nt.  The 
only  remaining  term  of  C/ [3329/]  is  the  fii'st,  depending  on  cos.  T  or  cos.(?i'i — nt-\-^ — s); 
and  if  this  were  multiplied  by  a  term  depending  on  the  angle  An't—nt,  it  would  produce  a 
quantity  of  the  required  form  ;  but  none  of  the  powers  and  products  of  cio ,  a',  a"  [3829Ar — ?»]; 
retamed  in  [3829^,  K]  contain  terms  of  the  third  order  depending  on  this  angle  ;  therefore 
we  may  also  reject  this  temi,  as  in  [3830]. 

*  (2416)  If  we  reject  the  terras  of  R  [3742],  mentioned  in  [3829],  which  we  have 
proved,  in  the  last  note,  not  to  contain  terms  of  the  required  form  and  order,  we  shall  obtain 
for  R  the  âmction  [3831].  This  expression  is  not  altered  by  changing  r,  v  into  r',  «', 
respectively,  and  the  contrary  ;  so  that  it  w'Ul  be  of  the  same  form,  whether  we  compute  the 
action  of  ?«'  upon  m,  or  that  of  m  upon  to'  ;  but  in  the  first  case  it  will  be  multiplied 
by  in,  in  the  second  by  m.  Supposing,  as  in  [3829fZ],  that  the  general  value  of  the 
fonction  R  [3831]  is  represented  by  u,  and  that  it  becomes  equal  to  U,  by  putting 

r  =  «,       ?•'=(/       v^^nt-\-s,       v'^n't-{-e',       v  —  »  =  ?t'i  —  n  ^  +  s' — s=T, 

we  shall  get  the  first  of  the  following  expressions  of  U  [3831c].  The  second  expression 
[3831<?]  is  deduced  fi-om  the  first  by  the  substitution  of  the  values  [.3743,  3744],  neglecting, 
however,  the  first  term  of  [3743],  which  makes  an  exception  in  the  value  of  A'-''',  in  the 
case  of  i  =  1  ;  because  this  term  produces  no  effect  in  the  present  calculation,  as  we 
have  seen  in  [3829o]  ; 

lJ=—m'.  \(v^-2  a  a.  cos.  T+a'^-^—{m'.y^.aa'.cos.  {n't+nt-\-s'+2) .{(?-  2  aa'. cos.  T-\-a'^\-i 

=  im'.S.A^'\cos.iT—im'.f.aa'.cos.{n't-{-7it-\-s'-j-s).S.B'-'\cos.{T 

=  i  m.  2 .  A^'\  COS.  i  T—  I  iri.  y^.  a  a'.  2 .  B'^  ".  cos.  [i  T-\-  'int  +  2  s— 2  n) . 

We  may  remark,  that,  in  reducing  [3831(/]  to  the  form  [3831e],  we  obtain,  in  the 
first  place,  from  [3749], 

cos.{n't-\-nt  +  s'-Jrs).:s.B^'\cos.iT=X.B^'\cos.{iT-\-n't-j-nt-{-s'-\-s) 

=  2.B''\cos.  {(i+l).T+2«^  +  2£}  ; 

and  by  changing  i  into  i — 1,  it  becomes  X. B'-'~^\ cos. \iT-\- 2 n t -\- 2  b\  ;  but  as  this 
quantity  is  to  be  multiplied  by  y^,  we  must  change  2n<-|-2s  into  2nt-{-2s  —  2n,  as 
in  [.3745'" — 3748],  and  then  the  value  of   U  becomes  as  in  [383 le]. 


VI.  i.^,^  8.] 


TERNIS  OF  THE  THIRD  ORDER  IN  e,  C,  7. 


55 


We  have,  in  Book  II,  ^22,  by  carrying  on  the  approximation  to  terms 
of  the  third  order  of  the  excentricities  [659,  668,  669],* 


—  ^e\cos.(3nt+3B—3^)  ; 
v  =  ni4-e+(2e  — ie=').sin.  (w^  +  s— tï)+  f  e-.sin.  (2nï  +  2s— 2x^) 

+11  e^sin.  (3w<  +  3s— 3a). 


Values  of 
r,  1'. 


[3834] 


*  (2417)  We  shall  now  commence  the  investigation  of  the  part  of  R  depending  upon 
the  first  term  of  [3S31e],  namely,  U^=^  m'.  2  .  ^''\  cos.i  T;  the  other  terms  depending 
on  B''"",  being  computed  in  [3840a,  Sic.].  Substituting  this  value  of  U,  in  the 
terms  [3829^,  A],  we  get  the  following  value  of  R, 


[3834o] 


1 

R  = 

2,    3 

4 

5,    6 

7,     8 

9,  10 

11,  12 

13,  14 

15,  16 

17,  18 

19,  20 

im'.2.^<''.cos.^T 


+ 


+  *  m' .  ag  .  2  .  f  — — \  .  cos.  I  r+  J  m' .  a'.  2  .  (  -7-^  j  -cos. i  T  , 

—  im'.  0.".  Si.  A^'\  sin.  iT 

,      „  /ddA(i)\  .^,    1     ,  ,  /dd.m\  .^ 

+  im'.ao2. 2  .    -r-7- ) .  cos. i  T+Jm'.ao a' .  2  .  (  -— —  ) .cos.i  T 
\  da^    J  "  \dada J 

+   l+i  m'.  a' ^ .  2  .  i^-^)  .cos.iT-i m'. ^a". 2 i .  (1^) . sin.  i  T 
—im'.oJa/'.Xi.  (-j^)  ■  sin.  i  T— ^rn'.a''^.  2  Î^A^'K  cos.  i  T 
+  A-'.S^2.('-^).cos.iT+.™'.ao^a'.2.(^).cos.ir^ 
+  ^-'-'^-(£^.)---^+^V..'.a'3.2.(^^).cos..-T 

+  <    ->'.a„V'.2;.('i^)  .sin.zr-i».'.aoa"^.2P.(^).cos.tr 

-im'.a'2a".2i.  (^)  .  sb. i  T-im'.a'a"^. 2^^.  (^^Vcos.i  T 

— àm'.aoa'a".2i/^^,') .  sin.  i r+^ . a"^. 2 i'. ^». sm.i  T 
\dada/  '   12 


Terras  of 

R 

depend- 
ing  on 


[38346] 


We  must  substitute,  in  this  expression,  the  values  of  a^,  a',  a"  [3829A: — ni],  and  retain 
only  the  terms  of  the  third  dimension,  and  of  the  form  5n't—2nt  [3834"],  in  which  the 
coefficients  of  n't,  nt  differ  by  3.  Now  as  these  coefficients  are  equal  in  the  angle  i  T, 
which  occurs  m  [38346],  this  difference  in  the  coefficients  of  ri't,   nt  must  arise  from  the 


[3834c] 


56 


PERTURBATIONS  OF  THE  PLANETS. 


[Méc.  Cél. 


[3834']     This  being  premised,  if  we  develop  R  [3831]  according  to  the  order  of  the 


powers  and  products  of  a^,  a',  a"  ;  and  it  is  evident,  from  [957^'",  Sic],  that  such  terms 
[3834d]  must  have  for  a  factor,  some  one  of  the  four  quantities  e'*,  e'^e,  e'e^,  c^.  If  we  take 
the  powers  and  products  of  tlie  quantities  a,,,  a',  a"  [3929/!: — to],  of  the  tliird  dimension, 
and  reduce  them  by  means  of  [17 — 20]  Int.,  we  shall  find,  that  the  greatest  angles  connected 
[.3834e]  with  these  factors  e'\  e'^e,  c' <?,  ê,  are,  respectively,  3  7P,  2W'^W,  W'-{-2Jr,  3fV; 
it  is  not  necessary  to  notice  the  smaller  angles  TV,  W ,  2  W —  W,  Sic,  because  they 
do  not  produce  terms  of  the  form  bn't — 2n  t  [3834c]  ;  substituting  ?F'=  T-\-nt-\-B—-a', 
W=  nt-{-s  —  -m   [3829c]  ;  they  become,  respectively. 


[3834e'] 
[38.34/] 


[3834êr] 


[3834^] 


[3834i] 


[3834ft] 


3  T+3Mi  +  3£  — 3«';  2T+3n<-f-3e  — 2i3'— ra; 

r_|_3,j;_j-3£_,3'— 2i3  ;  3m;  +  3£  — 3îï. 

Now  we  perceive,  by  inspection,  that  the  cosine  of  any  one  of  these  angles  is  multiplied, 
in  [38346],  by  a  tenn  of  the  form  ^/''.  cos.  z  T ;  and  its  sine  by  a  term  of  the  form 
^/''.  sin.  I  T;  the  products  reduced  by  the  formula  [3749],  are  found  to  depend, 
respectively,  upon  the  angles 

(i  +  3).T-}-3n<  +  3£  — 3«';  («  +  2).  r+ 3  n  <  +  3  e  — 2^^'  — ts  ; 

(i_|_l).  T-\-Znt-{-3s  —  z^—2-a;  i  r+ 3  n  <  +  3  s  — 3«. 

In  order  to  reduce  all  the  angles  to  the  form  i  T,  we  must  change,  in  the  first,  i  into  i—3; 
in  the  second,  i  into  i  —  2  ;  in  the  third,  i  into  i  —  1  ;  and  make  the  same  changes  in 
the  index  of  ^/''  ;  by  this  means  the  terms  in  question  become  of  the  forms 

e'3.  2  .  ^i''-=>.  COS.  (i  T+  3  Ji  <  +  3  £  —  3  ^)  ; 

e'=e .  2  .A^^'-^K  COS.  (i  T  +  3  n  «  +  3  s  —  2  73'—  i^)  ; 

e  62.2.^''-».  COS.  (i  T+  3  B  ^  +  3  £  —  TO  — 2  13  )  ; 

e» .  2  .  ^  w.  COS.  {i  T+  3  ÎI  i  +  3  £  —  3  w) . 

Putting  i=:5,  as  in  [3828],  these  expressions  become  of  the  same  forms  as  the  four  first 
terms  of  R  [3835],  depending  on  M'°^  M'",  Jf'^',  M<^\  respectively.  The  two 
remaining  terms  M''^\  M^^\  depend  on  JS""",  which  was  neglected  in  [3834a],  and 
will  be  computed  in  [3840a,  &c.].  We  may  remark,  that  the  exponent  of  e,  in  any  one 
of  the  terms  [3834A],  being  increased  by  i  —  3,  gives  the  corresponding  index  of  ^, , 
and  when    i  =  5,   we  have  for  this  increment    i  —  3  :^  2 . 

We  shall  now  proceed  to  the  computation  of  the  values  of  the  powers  and  products 
of    a,,  a',  a",     which  occur  in  the  expression  of  R    [3834J],   retaining  only  the  tenns 


[38342]      depending   on     e'' 


e^,     which   are  wanted    in    finding  the    values    of   M'-°\ 


VI.  i.§8.] 


TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  7. 


67 


terms  depending  on  the  angle     5  n't  —  2nt,     we  shall  obtain  an  expression     [3834"] 
of  the  following  form, 


J\P^\   M'--\   M'-^K       These  quantities  are  arranged  in  the  following  table,  in  the  order  in 
wliich  they  occur  in  [38346],  noticing  only  the  greatest  angles  mentioned  in  [3834e]  ; 


[3834m] 


2 
3 

4 

5 
6 

7 

8 

9 

10 

11 
12 
13 
14 
15 
16 
17 
18 
19 
20 


0-0 
a' 

a" 

tt,' 


=  — frt.c».  cos.  3  TV; 

=       J-l  e'  3.  sin.  3  W—  if  e^.  sin.  3  W  ; 


0 


=       i  0^  f3.  COS.  3  W  ; 


aott 
a' 2 


i  a'  «  .  e'2 e  .  cos.  (2  W'^  W) -\- ^a' a  .e' ê. cos.  ( ?F'+  2  7F)  ; 

irt'2.e'3.cos.3fF'; 

a^a"     =       fa.e3.sb.3»^— |«e'2e.sin.(2?F+?F)  — Jrt.e'e2.sin.(JF'+2ff) 
a'  a"     =  —  f  a',  e' 3.  sin.  3  ?F'+ 1  a',  e'e^.  sin.  (  ?F'+2 ?r)  -f  i  a',  e'^  e .  sin.  (2  W'^  W) 

i  c\  C0S.3  W+ye^cosX  W'-{-2  7F)+f  e'2e.cos.(2  fF'^-  W^)— f  e'3.cos.3  W 


= ftf3 


ao'  =  —  i  fl^.  e'.  cos.  3  W  ; 

a/  a'  =  —  i  a'  a",  e'  f?.  cos.  (  ?F'+  2  ?F)  ; 

a.oa'2  ==  — ia'2a.e"2e.cos.  (2?F'+ W'); 

a'3  =  — |«'3.e'3.cos.3l'F'; 

a;-ia"  =  —  \  «2.  c^.  sin.  3  W  +  *  «^  g'  ^a,  gin.  (  /F'+  2  W)  ; 

aoa"2  =       a.e3.cos.3?F— 2a.e'e2.cos.(?F'+2/^)  +  «.e'2e.cos.(2^'+rr)  ; 

a'^a"  =       i«'2.e'3.sin.3  JF'— ia'2.e'2e.sin.  (2R^'+ ?F); 

a'a"2  =       a'.e'3.cos.3  TF'— 2a'. e'^e .cos.(2ff' +?F)4-«'.e'e2.cos.  (?F'+2(F)  ; 

ao  a'  a"  =  —  1  a  a',  e  e^.  sin.  (  W'-\-  2  W')  +  J  a  a',  e'  ^^  e .  sin.  (2  fF'+  W)  ; 

a"3  =      2e3.sin.3fF— 6e'e2.sin.(fF'+2?'F)4-6e'2e.sin.(2?F'+fF)-2e'3.sin.3W''  . 


We  shall  use  these  expressions  in  the  following  notes,  in  computing  Jlf",  JV/<",  fiic.  ;  and 
we  shall  also  make  use  of  the  following  formulas,  which  are  deduced  from  [95.5e — A],  by 
taking  the  differentials  relative  to  T,  and  dividing  by  àzdT,  changing  also  W  into  ?F^ , 
as  in  [3T50A,  &tc.]  ; 

sin.  W^.is.  P.  A^'-> .  sin.  i  T=  —  ^  2  .  P.  ^^'l  cos.  {i  T-\-TV); 

COS.  fF, .  1  2  .  P.  A'^\  sin.  i  T=:       i^.P.  A^'\  sin.  {i  T+  IV,)  ; 

sin.  W,.\-s..P.  A''\  cos.i  T^      ^  2  .  P.  A^'\  sin.  (/  T-\-  W,)  ; 

cos.  fF, .  I  2  .  i3.  ^'0.  cos.i  T=       X  V  .  î3.  ^(0.  cos.(i  r+  fFJ, 

VOL.  III.  15 


[3835a] 


[38356] 
[3835c] 
[3835(f] 

[3835el 


58  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 


General 
form  of 


for  termaof 
the  third 
order- 


R=      M^''\e'\cos.(5  7i't  —  2nt  +  5s'  —  2s  —  3z^') 
~R  +ai^'Ke'-e.cos.  (5n'i  —  2  n  i  +  5  s'  — 2  s  — 2«'  — ^) 

+  M(^>.  e'e-.  COS.  (5  h'  i  —  2  jU  +  5  s'  —  2  e  —  ^'  —  2  ^) 
[3835]  +M(^'.e^cos.  (5  n'  t  —  2  n  i  -^  5  e'  —  2  s  —  3  ^) 

+  M'^' . e'f.  COS.  (5n't  —  2nt  +  ôs'  —  2s  —  zi'-~2n) 
+  M'-'Key-.  COS.  (5  n'  t  —  2n  t  +  5  e'  —  2  s  —  z^  —  2  n)  ; 
and  we  shall  find,  after  all  the  reductions,* 

!(2)  (3)  (3) 

389  6';'  +  201  a  .  ^-^+  27  a^  ^  +  a3.  Ç^ 
•4  a  a  da-'  rf  a^ 


[3836a] 


*  (2418)  The  pait  of  R  [3835],  depending  on  e'*,  may  be  put  under  the  form 
M'-°K  e'\  COS.  {iT-\- 3  W)  or  iH'»\  e'^.  cos.  (2T+3?F'),  using  T,  ÏV,  &lc.  [38296',  c]  ; 
the  coefficient  of  T  being  i=2.  Terms  of  this  kind  are  produced  in  i?,  by  multiplying 
the  quantities  which  are  connected  with  e'^  in  [3835aJ,  by  the  corresponding  terms  with 
which  they  are  combined  in  [38346],  and  then  reducing  the  products  by  means  of  the 
formulas  [955,  955a — h,  33356].  The  terms  depending  on  ^®  and  its  differentials,  are 
[38366]  giygjj  ;,^  ^jjg  value  of  Jli""  [3S36c/],  in  the  order  in  which  they  occur,  without  any  reduction, 
and  omitting  2  for  brevity  ;  so  that  the  terms  of  [3835a],  marked  4,  10,  20,  are  connected 

/dA'''i\  /rf2^(i)\  /rfS^Wx 

With    ^«;     3,   9,    18   with     (^);     7,  17  with     (-^-^j  ;      14   with     (—-) . 

Substituting  i^^2  [3S36o]  in  this  first  value  of  M^°\  we  get  the  second  value  of  [3836e]  ; 
[3836c]     and  this,  by  using  the  values  [1003],  becomes  as  in  [3836/],  or  by  reduction,  as  in  [3836^]. 
Lastly,  substituting   in   this  the   values    [996 — 1001],    we   get   [3836/j],    which   is   easily 
reduce  d  to  the  form  [3836]  ; 


[3836d] 


/(/./?(3)\  /d-A^~^\  „    /rf3./3f3)\ 

[3836e]  =W-^^--W-'.«^('-;^)+il-«-.(^)-.V-'--•(^ 

+  -.^6^'^'+18a.(— j+9a^(-^)  +  a^.(^( 
[3836g]  =^s^W.^«,^.^^^^«.(^__j  +  |^^^«3.^__j  +  _.«3.(-^-^j 


/-  (3)  (2)  (21  ■ 

7,1'      S  12)  dbk  c.    d^bi  ,    d3Ji   ( 

[3836/.]  =:i^,.)— 389  6,— 201a. -^  —  27  a2.^--a3.—f  , 


VI.  i.  §8.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  y.  59 

16    /  *  a  a,  dix.^  ria-*    > 


*  (2419)    Proceeding  as  in  the  last  note,  we  find,  that  the  part  of  R  [3835]  depending 
on    e'=e,    may  be  put  under  the  form      M'-'\  t'^  e  .cQs.{iT -^'2  W'-\-  W)    [3829è',  c],     [383ra] 
in  which  the  coefficient  of    T  is    i  =  3.      Substituting  the  values  [3835a]  in  [3834&], 
we  obtain  the  first  of  the  following  values  of  JV/'"  ;   observing,  that   the  terms  of  [3835a] 

depending  on  e'^e,  marked  10,  20,  are  connected  with  ^<'^  ;  the  terms  8,  16,  with    i— — j  ; 

the  terms  9,   18,  vnû\     (    ,  ,    )  ;      the   terms  6,   19,  with     (  ,   ',  ,)  ;      the   term    17 

\   da'   J  \dadaj 

with       C^-^^);      and  the  term  13  with     (^^^^^r^A-       Substituting    i  =  3    in  [3837(-],     [38376] 

we  get  [3837f?]  ;  and  this,  by  using  the  values  [1003],  becomes  as  in  [3837e],  or  by 
reduction,  as  in  [3837/].  Lastly,  substituting  in  this  the  values  [996 — 1001],  we 
get  [3837  0-],  which  is  equivalent  to  [3837]  ; 

[3837c] 
,    ,       /dd^\    ,,,,.,       ;     ,     ,a  /'d--A(0\        ^      ,    ,2       /rf3^U)>, 

=  -  \\«-  m'.  A  ^3>- 1^  m'.  a .  (^-j^j  +  f  |-  m'.  a'.  (^  j 

[3837rf] 

,     ,,      ,      ,         /ddJ10)\  ^       ,      ,„    /rf2^(3K  /d3jia)\ 


60  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 


(  W  (4)  (4)  ■) 

[3838]  „'iJf(.=  _^.-  3966';+ 184a.  ^  +  25a^^  +  a^^;* 

16     (  ^  da.  do.''  da.-^    ) 

*  (2420)    We  may  compute  [3838,  3839]  as  in  the  two  last  notes,  but  it  is  rather  less 
laborious  to  derive  them  from  M'-''\  M'-'-\  by  changing  the  symbols  as  below,  namely, 

[3838o]  For  i,     n't,     nt,     e',     i,     zî ,     •n,     e',     e,     «',     a;      a',     aj,  T; 

[38386]  Write     — i,      nt,     n't,     i,     s',     zi ,     -a',     e,     e' ,     a,     a;      a„,     a',    — T. 

The  changes  in  these  three  last  values  of  a',  o.^ ,  T,  evidently  follow  from  those  proposed 
in  the  other  symbols,  using  [3829À:,  /].  The  value  a"  [3829m]  is  not  altered,  except  in  its 
sign,  because  e.sin.  W^  changes  into  e'.  sin.?F',  and  e'.sin.  ?F'  into  e.sin.  fF,  &ic.  ; 
moreover,   A^'^   is  not  altered,  because  we  have     A'-~''' ^^^  A^'''    [954"];    we  also  have,  as 

[3838c]  j^  [3831c,  rf],  —\a^— 2a  a',  cos.  T-\- a'^l-i=i  X  .A^^\co5.iT  ;  and  as  the  first 
member  is  symmetrical  in    a,  a',   the  second,  or  A''\    must  also  be  symmetrical,  and  wll 

[3838rf]  not  be  varied  by  putting  a,  a'  for  a',  a,  respectively;  lastly,  the  expression  of  iî  [38346] 
is  not  altered  by  making  these  changes  ;  observing,  that  the  quantities  i  a",  i  T  remain 
unchanged.       Now  the  part  of  R  [3835]  depending  on    c'e^,    may  be  put  under  the  form 

[3S38e]  J»f  (2).  e'  e^.  cos.  {i  T+  2  W-{-  W),  in  which  the  coefficient  of  T  is  i  =  4 .  Comparing 
this  with  [3837a],  we  find,  that  by  making  the  changes  [3838a,  6],  the  expression  [3837a], 
corresponding  to  i  =  — 4,  will  become  like  [3838e],  and  M'^^  will  change  into  M'--^  ; 
we  may  therefore  obtain  the  values  of  M^"'^  [3838/1],  by  changing  a,  a',  i  into  «',  a,  — i, 
respectively  ;  then  putting  i  =  4,  we  get  [3838A'].  This  value  may  be  reduced  to  the 
form  [3838J],  by  the  substitution  of  the  values  [1003],  and  also  the  partial  differential  of 
the  second  of  this  system  of  equations,  taken  relatively  to    a,   which  gives 


[3838/] 


Reducing  the  expression  [.3S38i],  we  get  [3838^]  ;  and  by  the  substitution  of  the  values 
[996—1001],  it  becomes  as  in  [3838?],  being  the  same  as  [3838]  ; 

M'-''->  =  m'.A<~^{—^i^^^i^+iii:.n'.(^^yy^i-li^]+m'.a.(^^^y\  — 


[3838/i'] 


[3838i] 


dada'  J     ' 

/f/.-î'-DX  /(/.^HA  /ddJl'^^\ 

=W»'.-«»-tt..'.»'.(-^)+W-«'...(^)-iS.«'..«'.(,-^,) 


VI.  i.  §8.] 


TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  7. 


61 


a'  M'^'  = 


in 

48 


!(5)  (5)  (5)    -\ 

2  ri  a  d iS?  do?    ) 


C  (3)  ^ 

a'ilf  W  _  _  ^  .  ^  10  63 +a  .  lï^  >  ;t 
Id      /  ^  f/a    > 


[3839] 


[3840] 


f  (J)  (-1)  '41  -J 

=  7-r-, .  J  —  396  0  i  — 184  a .  — 25  a-',  -—^r a'.  — — -  (  . 

lb  a     f  -  a  a  da~  aa'^   ) 


*  (2421)  The  part  of  R  [3835]  depending  on  e^,  may  be  put  under  the  form 
M^^''.e^.cos.{iT-\-3  TF),  in  which  the  coefficient  of  T  is  x=5.  Comparing  this  with 
[3836a],  we  find,  that  by  making  the  changes  a,  a',  i,  &ic.  into  a,  a,  — i,  &c.,  respectively, 
as  in  [3838a,  6],  the  expression  [3836(/]  will  become  as  in  [3839i].  This  represents  the 
value  of  Jf^"",  or  the  coefficient  of  c^  in  [3835];  and  by  putting  i^5,  it  becomes  as 
in  [3839i']  ;  which,  by  means  of  [996—1001],  is  easily  reduced  to  the  form  [3839]  ; 


48a     C  *    '  do.     '  rfa2     '  do.    . 


t  (2422)  The  values  of  iV/C",  M*^)  [3840,  3841]  depend  on  the  second  term  of  [3831e]  ; 
and  by  retaining  only  this  term,  we  shall  have  JJ  ^  —  |  m'.  7^.  aa'.'S.  .  B^'~^K  cos.  T, , 
supposing,    for    a    moment,    that  T^z=i .  (n'  t  —  nt  -\-  s'  —  i)  -\-2nt  -{-2s  —  2  n . 

As  this  expression  is  multiplied  by  7^,  of  the  second  order,  we  need  only  notice  terms 
of  the  first  order  in  ao,  a',  a",  in  the  development  of  u  or  R,  and  we  shall  get 
for  this  part  of  jR,    the  following  expression  [3829^], 


«--C^)+'^'-(7 


""U.-.f^ 


ft'  / 


dT, 


obser\ing,  that  we  notice  in  this  article  only  terms  of  the  third  dimension.  The  values 
of  aQ,  a',  to  be  substituted  in  this  expression,  are  the  same  as  in  [3829A:,  Z]  ;  and 
by  retaining  terms  of  the  first  order,  w-e  have  ao  =  —  ae  .  cos.  fV,  a  ==  —  a'e'.  cos.  M'". 
The  angle    T,   represents  the  mean  value  of    i  .  {v  —  v)  -\-2v  ;     its  increment,  depending 

VOL.  III.  16 


[3838^] 
[3838Z] 

[3839a] 


[38394] 

[38396'] 

[3839c] 


[3840o] 
[3840a'] 


[3840A] 


[.3840c] 
[3840(/] 


62  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3841]  «'M<^'  =  ^.<7  6l  +  a.^^. 


r3840rf1     °"   ^'"  ^''   [^^~^"]'  '•''     o-"=i.{vJ — ■dJ -j- 2  !;,=  «!)/ — {i — 2).i;,,       and  by  substituting 
v;=2e'.sm.TV',     v,=  2e.sin.fV  [669],  we  get  a",  and  then  [38406]  becomes 

R^-e'.[a'.oos.W'.(^)-2i.sin.W'.(-^^\ 
[3840e] 

_e.^«.cos.^F.(^)+C2.--4).sin.rF.(j^)|; 
and  by  substituting  the  partial  differentials  of  U  [3840a],  we  obtain,  without  any  reduction, 
R=       ^-  m'.  c'  f.  COS.  TV.  J  a'  a  .  2  .  B^'-^K  cos.  T^  +  a' ^  «  .  2  .  C^^^)  ■  cos.  T,  I 

+  i  m'.  c'  72.  sin.  W  .a'a.Xi.  £('-i>.  sin.  T. 
[3840/-] 

+  J  m'  .  c  72 .  COS.  TF.  \a'a.-s:.B  <'-».  cos.  T^  +  a^  «'.  2 .  (^-^^)  .  cos.  T^  I 

—  i  m' .  c  7^ .  sin.  W  .a'a.X.  (2  i  —  4)  .  S''-»,  sin.  T^ . 

The  terms  of  this  expression,  depending  on  c' 7^,  contain  the  factors  cos.  tV'.cos.  T^, 
[3840g-]  and  sin.fF'.sin.T^,  both  of  which,  as  in  [17,  20]  Int.,  produce  the  terms  icos. (T^-^W), 
which,  by  putting  i  =  4,  becomes  icos.{5n'(  —  2nt-\-5s' — 2s — •ra' — 2n)  [3840»']. 
Comparing  this  with  the  term  depending  on  Jfef ''''  in  [3835],  we  get  the  first  of  the 
following  expressions,  omitting  2  for  brevity,  and  then  by  successive  reductions,  using 
[963''',  1006—1008],  we  finally  obtain  [3840/],  which  is  easily  reduced  to  the  form  [3840]  ; 

[3840/1]     M'-^^=-i^m'.  i  a'  a  .B^'-^^-{-  a'^a.  (^fj^)  \  —  ^  m'.  a'a.i.  S^'-" 

[3840i]  =  J^  m'.  a' a . \—  1 B'^^  +  a'.  (^-^^  j=  J,  m'.  a'n .  J-  7  5«'  +  [-3B'^>-a .  (^')]  I 

(3) 

,:««,  =,,.,..4-,OB™-..(i^')|=,,„..„.„.)_i£,4'_^..^  I 


[3840i] 


ICa     C  2     '  rfa 


In   like    manner,    the    terms   of    [3840/"],    depending    on      e  7^,     contain   the    factors 

COS.  ^F.  cos.  T4,      sin.  ?r.  sin.  T4,       producing   the  term       |  cos.  (T4+ ^F),       which, 

[:3840»i]     by  putting     i  =  5,     becomes       ^cos.(5n't  —  27it-{-5s — 26  —  «  — 2n)     [3840o']. 

Comparing  this  with  the  term  depending  on  M^^^   [3835],  we  get  the  first  of  the  following 


VI.  i.  §8.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  y.  63 

Hence  we  deduce* 

General 

+  a'M(^).  e'e~.  sin.  (^+  2  w)  +  a'M^^'.  el  sin.  3  «  [3842] 

+  a'M<^'.  e'7'.  sin.  (2  n  +  ^')  +  a'M'^'.  e  y".  sin.  (2  n  + ..). 


and  of 


We  shall  get     in',  a'  P',     by  changing  the  sines  into  cosines,  in  this  expression    °^^,' 
of    in!,  a'  P  ;     and  it  will  be  easy  to  deduce  the  values  of    a  P,    a  P,    by      [3843] 

expressions,  in  which  we  must  put    i  =  5,    and  then,  by  reducing  as  above,  it  becomes  as 
in  [3840p]  ;  whence  we  easily  deduce  [3841], 

M^^^=j'^m'.  I  «'rt.B<'-"  +  a2rt'Y!^^")  I  -j-j\m'.a'a.{2i—4).B^'-'^  [3840n] 

[3840o] 


(4)- 


16  o'    C        t  "T    d  a  ) 

*  (2423)    In  the   case   of     i  =  5,     if  we  use,  for  a  moment,   the  abridged  symbol     [3842a] 
T5=5n't — 2nt-\-5e' — 2s,     the  value  of  R   [3810]  becomes 

R  =  m'.  P.  sin.  Tg  -f  7n'.  P.  cos.  T^ .  [3842o'] 

Now  each  tenn  of  R  [3835]  may  be  easily  reduced  to  the  form  [3842»']  ;  since,  if  we 

take,  for  example,  the  fii-st      ^<'".  e'lcos.  (T^  —  3ra'),      and  develop  it  by  [24]  Int.,  it     [38426] 

becomes    J/"'>.e'3.sin.3w'.sin.T5+^/<®.e'3.cos.'n'.cos.r5.      Comparing  this  witli  [3842a'], 

we  get  for  the  parts  of    m'.P,  m'.P',     the  following  expressions, 

m'.P  =  Jlf(°i.e'3.sin.  3^3',  m'. F=M^°\  e'^  cos-Sz/,  [38426'] 

as  in  [3842,  3843].      In  like  manner,  we  obtain  the  other  terms  of  [3842]  from  [3835]. 

The  values  of   P,   P',    deduced   from   [3842,  3843],   may  be  put  under  the  following 

fonns,  which  will  be  of  use  hereafter.  Expres- 

sions of 

P=S.M'.e"'.  e".  f\  sin.  (6'  îi'-f  6  ts  -f  2  c  n),  ^'  P- 

[3842c] 
P'=  1 .  M'.  e"'.  e\  f.  COS.  (6'  î3'+  6  rt  +  2  c  n)  ; 

2  being  the  characteristic  of  finite  intégrais,  and   h\  b,  c,   integral  numbers,  including  zero, 
satisfying  the  equation    è'  +  6  +  2c=:3. 


64  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3843']     multiplying     a' P,    a' F,     by     ~     or     a.        We  shall  then  find,  by  putting 
i  —  5,     in  the  expressions  of   ôv    and    —    [3817,3827,3821],* 

Ex  près - 

sioiiofthe  /'  (  ^n    HP  ?t«    rltfP'         "^ 

\  ^-P'+T^^Vt.-,-/    o   P  ^,ol  -sin.  {5n't-2nt+5s'-2s) 

ÔV  —6m'. n^     )         i.  (5n—2n).dt        {5n'—'2nf.dt^)  ^  '  ' 

of  the  °" 


third 
order. 


[3844] 


(5n'_2„)9    \        r  'ia.dP'  Sa.ddP 


(      „  2a. dP'  Sa.ddP       )  ,      , 

—  ^  ciF—      ,  ,,  — ,g  ,    o  V,  j.o  ^  •cos.(5?i'/-2n<+5s'— 2s) 

C  (5n'— 2>i).d<       (5n'—2nf.dt~  )  ^  '  ' 


2   /  \    — „   cc'v        n..  V    r    r  J       o  cA 


5  n' — 2  n' 


'  —  a^f—ysm.{rjn't—2nti-5s'—2s) 


—  ^He.s'm.  {5n't  —  2nt-l-5E'—2s—zj-\-A) 
-]-^Ke.s\n.{5n't—4nt-J^5s'—4s-\-7S-\-B)  ; 

Exprès-  ^  J, 

terTo.-'"    — =  H  .cos.(5nV— 3/U  +  5s'— 3e+^)  — iîe.cos.(5n'^— 2ra«  +  5£'— 2s— «+^) 

of.the  _|_     He.cos.{bn't — Ant-\-bs' — As-\--ui-\-A) 

order. 

[3845]  +^^^.\aP.sm.{bn't  —  2nt-^bs'—2i)-YaP'.co5.{^n't  —  2nt  +  bt'—2s)\. 

[=3845']  If  we    suppose      i  =  — 2,t      and    change    the    elements    of     m     into 


[3844a] 


*  (2424)    Adding  the  terms  of  .5^  [3817,3827],  and  putting    i=b,    we  get  [3844]. 
Putting    i  =  5,    in  [3821],  we  obtain  [3845]. 

t  (2425)    By  restricting  ourselves  to  terms  of  the  first  order  of  the  masses,  and  of  the 
[3846a]     third  dimension  In     e,   e',   y,     the   expression   of    —    [3831]   becomes  symmetrical  in  the 

elements  of    m,  m',   so  that  these  elements  may  be  Interchanged  without  altering  this  value 

R  R 

of    —    [3831  «,  «'].      The   same  symmetry  obtains  in  the  expression  of   —   [3810]  ;  for 

[384(36]  if  we  put,  for  a  moment,  T^  =  5n' t  —  2jit  ^5s'—2s,  T,.=  5nt — 2  ?f'C+ 5  s  — 2e', 
and  retain,  in  [3810],  only  the  two  terms  arising  from  the  successive  substitution  of  the 
values     »  =  5,     i  =  —  2,     It  becomes 

[3846c]  ^=P-  sin.  T,  +  P'.  cos.  T,  +  P^ .  sin.  Tg  +  P'o-  cos.  T,  ; 

Py,  P'o,  Tq,  being,  respectively,  the  values  of  P,  P',   T^,  when  the  elements  a,  n,  e,  &c. 

are  changed  into    a',  n',  e,  Sic,    and  the  contrary,  this  being  necessary  to  preserve  the 

[3846(/']     symmetry  [3846»].      In  computing  the  action  of  tn    upon  m,   it  Is  not  necessary  to  notice 


VI.  i.  §8.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  c,  y.  &b 

the  conesponding  ones,  relative  to    Ht',     and  the  contrary,  we  shall  obtain 

C     ,„,  ,        '2a'. (IP  Sa'.ddP'       )      .      ,,    ,       ^       ,   ^  ,     r^  ^  \ 

I  '{5n'—2n).dt       {57i'— inf. dt^  y  ^  '  ^f 

(      ,„  2«'.rfP'  Sa'.ddP         }  /r     '.       f>     V   1    C   '       O    \  (        Expros- 

I  (5n'-2n).rfi       i5n'-2nf.dt^  S  ^  'J      tcrmsof 


_    .         15m.)i'- 


he 
terms  of 


iv' 

of  the 

third 

2m. n'      )  vaa  /  •  ■  -  r  order. 


«'-.r^j.cos.(5?i'^— 2n^  +  5e'— 2s) 


5n'— 2n    )        .„  /dP 


—  a'^.(—\.sm.{on't—2nt-\-b^—2s) 


[3846] 


—  IH'e'.sin.  (57!'<  — 2)U  +  5s'— Qe— t3'+^') 
+  îi:V.sin.  (3n7  — 2;U  +  3£'— 2ê-[-w'+B')  ; 

t    /  Exprès- 

^=  if'.cos.(47i'<— 2n<  +  4£'— 26+^')— iîV.cos.(5n'!!— 2n!;-f5£'— 2e— w'+^O  ,';°"„^"ffi- 

+     i/V.cos.(3«V— 2n<  +  3£'— 25  +  w'  +  ^')  «nhe 

order. 

^°™'"'     |«'P.sin.(5n'<  — 2ni  +  5E'— 2£)+a'P'.cos.(5n7  — 2n<  +  5£'— 2£)}  ;  [3847] 


5n'— 2n 


if',  cos.  (4  n'  i  —  2  n  ^  +  4  e'  —  2  £  +  J'  )     being  the  part  of    — r^-   depending      [3848] 
onthe  angle     An't  —  2nt*     and      ^'.  sin.  (4n'i  — 2n  i +  4='  — 2£+-B') 


the  angle    T^,   because  it  does  not  produce  terms  having  the  small  divisor     5  n'  —  2n.    [.3846rf"] 
In  making  the  change  of  the  elements  of  m    into  those  of  m',   according  to  the  directions 

[3845'],  the  value  of    — ,     corresponding  to  the  action  of  m   upon    7n',   becomes 

-  =  Po  .  sin.  T.  +  P'o .  COS.  To  +  P.  sin.  T,  +  P'.  cos.  T, .  [3846e] 

m 

The  second  members  of  [3846c,  e],  are  evidently  identical  ;  but  in  this   last  expression 

the  terms  depending  on  the  angle    Tg,    are  derived  from  those  of  [3846c],  which  depend     r„o,^^^ 

on  i^ — 2  ;  by  changing  the  elements  ?«,  «,  e,  Sic.  into  those  of  m',  a,  e',  &c.,  as  in  [3845']. 

Lastly,    we   may   observe,    that    the    quantities      P,     P',    connected,    respectively,    with 

sin.  Tj,    cos.  Tj,     are  the  same  in  [.3846c,  e].      Hence  we  may  derive    ôv    from    Sv,    by 

taking  the  sum  of  the  two  parts  of    5  »    [3817,3827],  putting    i  =  —  2,    then  changing 

m,  a,  n,   e,  H,  K,  k.c.    into   m,   a',  n',  e,  H',  K',  &.C.,    respectively  ;  by  which  means 

we  get  [3846].     In  like  manner,  we  may  derive  [3847]  from  [3821]. 

*  (2426)    These  terms  correspond  to  [3814,  3826],  putting    i=  — 2,    and  changing 
the  elements  as  in  [3845']. 

A'OL.   III.  17 


66  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

being  the  part  of  6  v'  relative  to  the  same  angle.  In  these  various 
inequalities,  we  shall,  for  greater  simplicity,  refer  the  origin  of  the  angles  to 
[3840]  the  common  intersection  of  the  orbits  of  Jupiter  and  Saturn  ;  as  Ave  have 
already  done  in  the  development  of  the  expression  of  R  [3736 — 3738],  and 
shall  continue  to  do  in  the  following  article.  For  the  sake  of  symmetry, 
we  shall  retain  the  angle  n,  which  must  be  supposed  equal  to  nothing. 

lioZf  *  We   shall  determine  the  differentials      - — ,        ,  '     ,     - — ,      — — ,      in 

,P,dir,  iW        dt^   '       dt  '        dt^   ' 

^^-  the    following    manner.         We    shall    compute,    for    the    two    epochs    of 

[3849]      1750   and    1950,    which    embrace    an    interval   of    200   Julian    years,    the 

,  -       (7e         (/«        de'        d-ul        d  y        du  i     i    n 

values  or       --,      —,      —,     —— ,     —,     -— ;       and  shall  represent  these 


[3850] 


dt'      dt  '      dt'       dt  '      dt'       dt 
quantities,  at   the    second    of  these    epochs,  by       — ',      — -^,      -~-,     &c.  ; 

we  shall  then  have,  by  supposing   t   to  be  expressed  in  Julian  years,* 

[3851]  ^'^^  +  200.^% 

dt         dt  dt'' 

in  which  the  differentials    de,   dde,    in  the  second  member,  correspond  to 
the  epoch  1750.       The  value  of  e,t    for  any  time    t,    neglecting  the  cube 


*  (2427)    We  have,  as  in  [607,  &c.], 
[3850a]  ,^f7+,.(^)  +  .,..(^J_^)  +  &e., 


[38506] 


d  €  (i€ 

u  beins;  a  function  of  ^,  which  becomes  U,  when   t=0.      Now  puttine    m=— -',    C7:= — , 

,-  T  ,  ••11/'  r  '^^,       ^^    1         dde 

as  in  [3850],  we  get,  by  retaining  only  the  farst  power  of    r,      77  ="  77  +  ^  •  jTs  >      which, 

by  putting    ^=200,    the  interval  mentioned  in  [3849'],  becomes  as  in  [3851].     From  this 

roo,-/. -,  ddi  1       \de,        de}  de     de,  . 

[38.50c]     we    get     ^^  =§00  '  Jdl  "  rfIS  '       ^^^^   ^^"'"'^  °^    rf"i  '  ^  '       being  computed,  as  m 

[4238,  he,  4330a,  &c.],  for  the  epochs  1750,  1950  ;  we  obtain,  by  substitution,  in  [3850c], 

dde 
the  value  of      -t^j     corresponding  to  the  epoch  1750. 

t  (2428)    Putting    U=e,    M=e,,     in  [3850«],  we  get 
[•3852a]  e=e  +  t/^^+it^.'^        [3852]; 

in  which  we  must  substitute  the  values  of   e,    ^^  ,    ^    [3850,  3850c],  for  the  epoch  1750^ 


VI.  i.  §8.]  TERMS  OF  THE  THIRD  ORDER  IN  e,  e',  7.  67 

of  t   and  its  higher  powers,  is 


de        (1  d  I 


clt'      dt-' 


being   supposed    to  correspond   to  the   year    1 750  ;    this 

expression  maij  be  used  for  ten  or  tioelve  centuries  before  or  after  that  epoch*      [3853] 
In  like  manner,  we   may  determine  the  values  of    ^,    e',    ^',    7,    and    n  ; 

Til  [OOOO  J 

thence  we  may  compute  the  values  of  P,  corresponding  to  the  three 
epochs  1750,  2250,  and  2750.  If  we  represent  these  values  by  P,  P,,  P„, 
and  the  general  expression  of  P  byf 

P4./     'll^'l   ^i^.  [3854] 

^+^•77  +  2  '  dt^    '  ^ 

we  shall  have,  by  putting  successively,    t  =  500,    t  =  1000, 


dP.     950000    1    — ^ 
—  +    250000.2-   ^^, 


P  =P+    500.^+    250000  . 1 . -r;^  ;  [3855] 


Values  of 
dP,  ddP. 

[3856] 


p^  =  p  + 1000 .  ^  + 1000000 .  è  •  ^  ;  ^^855'] 

Ct  Z  (t  I 

hence  we  obtain! 

dP       4P  — .3P  — P,  ddP       P„—2P,  +  P 

d t  ÏÔÔÔ  '  ~dl^  250000 

*  (2429)    To  give  some  idea  of  the  rapidity  with  which  the  terms  of  the  series  [3852] 
decrease,  we  may  take  the  value  of  e'"  [4407]  for  the  case  of    <  =  1000,    and  we  shall 

find     t  .-^=329%     — i<2       «=8^;      so  that   the  second    is  about  ^V  P^rt  of  the     [3853a] 

(13  e 
fii-st  ;   and  with  the  same  rate  of  decrease,   the  third  tenu     it^-:r^    will  be  insensible;     [38534] 

similar  remarks  may  be  made  relative  to  tlie  other  terms  of  [4407,  Stc.]. 

t  (2430)    Tlie  expression  [3854]  is  similar  to  [3850a],  and  by  putting,  successively, 
<  =  500,    f=1000,  we  get   p,  P„  [3855,3855']. 

Î  (2431)    Multiplying  [3855]  by  4,  [3855']  by   —1,    adding  the  products,  and  then 
dividmg  by  1000,  we  get      —     [3856].       Again,   multiplying  [3855]  by     — 2,    adding     [38560] 
the  product  to  [3855'],  and  then  dividing  by  250000,  we  get     jjy    [3856]. 


68  PERTURBATIONS  OF  THE  PLANETS.       [Méc.  Cél. 

9.     The  terms  depending  on  the  ffth  powers  of  the  excentriciiies  may  have 

[3856'!     "  sensible  influence  on  the  great  inequalities  of  Jupiter  and  Saturn  ;  but  the 

calculation  is  very  troublesome   on   account  of  its  excessive   length.      The 

importance  of  the  subject  has,  however,  induced  that  very  skilful  astronomer 

Burckhardt,  to  undertake  the  computation.     He  has  discussed,  with  scrupulous 

.ggg„      attention,  all  the  terms  of  this  order  depending  on  the  angle     bn't  —  2n^, 

neglecting    merely    those    terms    which    depend    on    the    products    of    the 

excentricities  by  the  fourth  power  of  the  mutual  inclinations  of  the  orbits  ; 

which  produce   only  insensible   quantities.      The  expression  of  R   [3742] 

[3857']     corresponds  to  the  action  of   in'  upon  m  ;    and  the  part  of  the  expression 

which  has  the   most  influence  on  this  inequality,   is  the  product  of  m'  by 

the  following  factor,* 

„  J  ~.ri-'.\cos.{v'—v)  —  cos.{v'-\-v)\ 

[3858]  -=  —  -—====  + 3-. 

m  Vr'^—'2rr'.cos.{v'—v)+r'~  [,■''— 2rr'.cos.{v'—v)^r'^^ 

[3858']      This  factor  is  the  same  for  both  planets  ;\    by  developing  it,  and  noticing 


*  (2432)    If  we  proceed  by  a  method  similar  to  that  used   in  [3d29«,  &.C.],  we  may 
prove,  as  in  [3829?i,  &c.],  that  the  second  and  third  terms  of  R  [3742],  namely, 

[3858o]  J-  .  — -{cos.  (d' — v)  —  cos.{v-\-v)], 

do  not  have  any  influence  in  producing  terms  of  the  order  now  under  consideration,  depending 
on  the   angle    bnt — 2nt,    and  by  neglecting  them,  and  also  the  first  term  of  [3742], 

which  is  noticed  in  [3S61,  3868],  we  obtain  the  value  of    -r    [3858]. 

t  (2433)    As   7   enters  into    R  [3858]   only  in  the  even  powers,   and  the   quantities 
[3859a]     multiplied  by  y^    are   neglected  [3857],  the  terms  of  R  of  the  fifth  order,  must  contain 
factors  of  the  following  forms, 

[38596]  e'^      c'^e,      e'^e^,      t'^c\      e' e^      e"  ;  y^e'^,      y^e'^e,      y'^  e' e\      y^  e^  ; 

of  which  the  six  first  terms  compose  all  the  combinations  of  e,  t',  of  the  fifth  dimension, 
and  the  remaining  terms  all  the  combinations  of  e,  e,  of  the  third  dimension,  multiplied 
by  7^  of  the  second  dimension.  Now  we  see,  as  in  [957"",  957''^],  that  if  R  contain  a 
series  of  terms  of  the  form     ?;*'.  Ar.  cos.  (5?i'/  —  2nt-\-A),      the  first  term  of  the  series 

[3859c]  will  be  of  the  order  i' — i  =  5 —  2^3,  or  of  the  third  order  ;  the  second  term  will  be 
of  the  order  i' —  i-\-2,  or  of  the  ffth  order  ;  and  by  noticing  only  terms  of  the  fifth 
order,  the  angles  will  become,  respectively,    of  the  forms  [3859].      For  in  the  elliptical 

[.3859d]     motion  the  angle    nf-\-s    is  always  connected  with  — w,  7i't-\-^  with  — «'  [669,  957'^']  ; 


VI.  i.  §9.] 


TERMS  OF  THE  FIFTH  ORDER  IN  e,  e',  7. 


69 


only  the  products  of  the  excentricities  and  inclinations  corresponding  to  the 
angle     5  n't —  2  w  ^,     we  shall  have  a  function  of  this  form, 


R 

VI 


~=      N  "".  COS.  (5  «'  i  —  2  ?U  +  5  s'  —  2  £  —  4  ^'  +  -.:) 
+  iV (' ) .  COS.  (5  n'  i  —  2  n  Ï  +  5  a'  —  2  £  —  3  ^') 
-{-N^''\cos.{5n't—2nt  +  ôs'  —  2s  —  2^'  —  ^) 
+  N'-^K  COS.  (5  n't  —  2nt  +  5  ='  —  2  s  —  ^'  —  2^) 
+  N '^'.  COS.  (5nt  —  2nt  +  5^'  —  2s—3z^) 
+  iV(^>.  COS.  (5  7i'  t  —  2n  t  +  Ô  s'  —  2  s  +  z^'  —  4>^) 
+  TV  (**'.  COS.  (5  71'  t  —  2n  t  +  5  s'  —  2s  —  2^'  +  ^  —  2u) 
+  N  '-'K  COS.  (5  n'  t  —  2  n  t  +  5  B  —2  s  —^'  —2n) 
+  iV(^'.  COS.  (5  n'  t  —  2  71 1  +  5  s'  —  2  s  —  ^  —  2  n) 
+  ^<^cos.  (5n'i  — 27if +  5s'  — 2£  +  ^'  — 2^  — 2n). 
and  we  find* 


[3858" 


Forms 
of  the 
terms  in 

R 

uf  the  fifth 
dimen- 
sion in 


(0)         [3859] 


and  in   tlie  terms  depending  on    7^,    the  angle     2n't~\-2s'     is  connected  with    — 2n; 
so  that  if  the  coefficients  of    w,  -n',    n,    be  represented  by   g,  g",  g",  respectively,  we 
shall  always  have,  by  noticing  the  signs    g -\- g' -\- g"  :^ — 3;     which  is  similar  to  [959],      [3859e] 
changing  the  signs  of  the  coefficients.      Moreover,  the  sum  of  the  coefficients   g,  g',  g", 
considering  them  all  as  positive,  must  not  exceed  5   [957'"],  because  the  present  calculation 
is  restricted  to  terms  of  the  fifth   order.      Thus,   for  example,  a  term  depending  on  the 
angle      5  n't  —  2nt-\-5^ — 2  s  —  5to'+2«,      must  be   rejected,  because  the  sum  of    [3859/] 
the  coefficients  of  -n',  «,    taking  them  positively,  is  7,  corresponding  to  terms  of  the  seventh 
order.      Now  a  slight  examination  will  show,  that  the  values  of  g,  g,  g" ,   which  satisfy  the 
equation    g -^  g^ -\- ^' ^ — 3     [3S59e],    with   the    prescribed    condition,    are    as   in    the     [3859g-] 
following   table  ;    the    corresponding    numbers   being   placed    in    the    same    vertical    lines. 
These  numbers  agree  with  [3859]  ; 


Values  of    g',    _4,     —  3,    —  2,    —  1,         0,  1; 

Values  of    g,  1,  0,-1,    —2,    —.3,    —4; 

Values  of    g",         0,  0,         0,         0,  0,         0  ; 


■2,    —1,         0,         1; 
1,         0,    —1,    —2; 

■2,    —2,    —2,    —2. 


[3859;i] 


*  (24.34)  The  signs  of  ah  these  values  of  a' N^'>\  a!  N^'^',  &c.  [.3860— .3860'"],  have 
been  changed  from  the  original  so  as  to  correct  the  error  mentioned  by  the  author 
in  [5974,  Sic.].  Before  the  discover)'  of  this  mistake,  he  had  computed  and  used  these  [3860a] 
erroneous  values  in  ascertaining  the  inequalities  of  Jupiter  and  Saturn  [4431,  4487]  ; 
hence  it  becomes  necessary  to  apply  the  corrections  of  the  mean  longitudes,  given  in 
[5976,  5977,  &ic.].  We  have  given  [3860—3860'']  as  they  were  printed  by  the  author, 
VOL.  III.  18 


70 


PERTURBATIONS  OF  THE  PLANETS. 


[Méc.  Cél. 


[3860]      a'iV('"  =  — 


768" 


(')                                   (1)                              (1) 
3138  b  ,  —  13  a.  — -^  —  1556  o?.  ——  —  438  a». 1 


à 


—  38a^ 


(1) 


cW 


d  a. 
f/as 


do.^ 


Terms  of 
the  fînh 
dimen- 
siou  in 

r,  e',  y. 


[3860'] 


«'iV(»=_ 


+ 


e'3y2 

384"" 


(2) 


—  (20267  e'  2+  24896  ê)  .h''— (7223  e'=+  8 1 44  e^) .  a . 


(2) 


(2) 


f/2i, 


(2) 
,3 


z^ .  <  +  (  1 094  €'-+  3692  e^) .  a=.  Vf  +  (482  e'^+ 1 436  e^) .  a^  '-^^ 

'  "°    )  a  a"'       ^  c/  a' 

(2)  (2) 

+  (41  e'"~+  140 e^)  .  a\  ^  +  (e'2  +  4e^)  .«-^^ 


(3)  s 


590a.(6^  +  6j  +  255a^(^l^  +  ^) 


0)  (3),  ,  (1)  (3) 

2~  +    w.,2    /  ~i    ""  •  V~T7ir    I 


f/a2 


f/  tt'  d  a' 


[38606] 
[3660c] 

[:3860d] 
[36(!0f] 


[3860/] 


correcting  the  signs  as  above  ;  but  without  pretending  to  verify  more  tlian  one  or  two  terms 
of  each  of  the  coefficients.  Tiie  calculations  of  Burckliardt,  on  this  subject,  are  given  in 
the  Mémoires  de  FInstttnt,  T.  IX,  1808,  p.  59,  supp.,  but  generally  with  wrong  signs. 

From  what  has  been  said  in  the  preceding  notes  [3809a — 38.56rt],  concerning  the  terms 
of  the  third  order,  we  may  form  some  idea  of  the  great  labor  of  computing  and  reducing  the 
terms  of  the  fifdi  order  [3860-3860''^].  The  series  [3829^—?»,  38346]  must  be  very 
much  increased  by  the  introduction  of  terms  of  the  fourth  and  fifth  orders  ;  a  table  similar 
to  [38350]  must  be  formed,  containing  terms  of  the  fifth  order,  depending  on  the  proposed 
angles  and  on  the  powers  and  products  of  a^ ,  a',  a",  as  far  as  the  fifth  order  inclusively. 
Then  we  obtain,  as  in  [38.36f/,  3837c,  &ic.],  values  of  iY'»>,  JV"',  &c.,  depending  on  ^''' 
and  its  differentials  relatively  to  a,  n'  ;  which  may  be  reduced  to  the  differentials  relative  to  a 
only,    by  extending  the  table   [1003]    to  differentials  of  the  fifth   order;    finally,   by  the 

substitution  of  the  values  ./2'*',  B'-'\    and  then- differentials,  in  terms  of  ftj^,    èj,   and  their 

differentials  [996—1003],  we  get  the  required  values  of  JV"",  JV"',  &ic.  This  short 
sketch  of  the  method  of  computing  the  terms  of  the  fifth  and  higher  orders,  must  suffice  ; 
more  minuteness  would  be  inconsistent  with  the  prescribed  limits  to  the  notes  on  this  work  ; 
in  which  we  have  proposed  to  point  out  and  illustrate  the  methods  of  computing  the  various 
inequalities,  by  occasional  examples,  without  attempting  to  verify  the  immense  number  of 
numerical  calculations  with  which  the  work  abounds. 


VI.  i.  ^9.]  TERMS  OF  THE  FIFTH  ORDER  IN  e,  e',  y.  71 

(3) 

—(109392e'2+53064e=).&'"— (42368  e'^+23436.e^).a.^ 
'''^''~      '76^*\  +(1064e'^+2088e^).a^Ç^+(1572e'^+1710e^).a='.'^ 


(3)  (3) 

+  (152  e-+192e==)  .a^  i^  +  (4e-+6e^).a^^ 


e'^e^s 


/  (2)        (4)\  „    fdb^         dbi. 


(2)  (4) 


128  ,  (2)  (4).  /  (2)  (4) 


1 


da?   ^   da?  y     '  \  (/a» 

(4) 

—(42912c'^+199848e'-2).6'"— (21728  e2+82032e'^).a.'" 


è  da. 


(4)  (4) 

+  (116  e'-+210  e'^)  .  a^  ^  +  (4  e^+  6  e'^)  .  a^.  ^ 


(3)  (5) 


580a.  (63  +  63)  +234a^(^+^ 
\     z  s  '  \  da.  da. 

/  (3)  (5)v  /  (3)  (5), 

I  d'^hs.        d^h^\  fd^h^         d^b"\ 

(51 

—  (11840e=+152000e'^).6®— (6560e-+65168e'2).a.^ 

4  </a 

g3         )  „    (5)  (5) 

"'^'' ~     768  •  \  —  (592  e^+  4720  e'^) .  a^  ^  +  (  1 52  e^  920  e'^)  .  a^.  ^- 

(5)  (5) 

+  (26  e"  +  128  e'2)  .  a^  Ç^  +  (e"-  +  4  e'^)  .  a^.  ^ 
554a.(6:+6")+222a^(^  +  ^-^) 

'  /  (4)  (6)v  ,  (4)  (6), 


384  ' 


[3860" 


(4)        ,^,«^«   o  ,  r^^/^oo   «X       db^ 

Terms  of 


,    g      1  (4)  (4)      I         the  fifth 

a'iV(^)=__./  _(640e2+2970e'=).a=.  ^  +  (864e^+1854e'2).al  1_^ 


sioo  in 

c,  e',  7. 


[3860" 


[38601- 


72  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 


(6)  „     (O 


[3860^]  «'A^W^     1_^ 

768 


41448. 6/+ 18392  a..  ^  + 1780  a=^.    ,  , 

4  do.  «a^ 


(6)  (6)  (fi) 

156  a^  î-^  —  29  a^  lif  —  a^  ^ 


C  ,o,  (2)  (2)  (3) 

[3860V.]  a'iV<^)=  ^^.  <  —  85  a  .  6  3  +  85a^^+  21  a^.  ^  +  a^  1-1^ 

1-28      (  ^  a  a  «/a-'  rfa^ 

(3) 
(3)  f]  7,  3 

3 
2 


Terms  of 
the  fiflh 
dimen- 
sion in 


1 


e,  e',  r.  \    (56  e^  +  842  e'=)  .  a  .  6  3  +  (4  e^  +  87  e'^)  .  a^  -ip 

[3860vii]  d'  ]\fO)^     <^^  ■ 

128      1  (3)  (3) 

-(16e^+20.a3.^-(2e^+e-).a^Çi| 

(4) 
_  _  (174  e^  196  e'^) .  a.  6*^'  +  (50  e-+ 180  e'~) .  a=,  '^ 

[3860vi.i]  ^('^^(S)—      IZ!. 

128     \  W  „    W 


1 


.3îÇ^  +  (2e-+e^).a^îÇM 


+  (14 e'^—  e^)  .  «.3.  — f  +  (2  e'^  +  e"^)  .  a^ 


e'e^  yS     ^  (6)  (5)  (r.)  ■\ 

[3860U]  a'iV<«)=:l^.<580a.èr+86a^^— 8a3.1!ij_a^^i    •. 

(  ?  eta  da-  «/a-*) 

When  we  consider  the  action  of  m!  upon  m,  we  must  augment  «W"'  [3860], 
by  increasing    h       with  the  term r?   or     — a    [3743],  which  increases 

5  (t 

3125  a.  c'*e 
a'N'-"''    by     —^ .*       When  we  consider  the  action  of   m   upon    m', 

768  '■ 


[3861] 


*  (2435)    In  [996],  we  have,  generally,     —  .  è  '  =  —  ^''' ;      but  in  the  particular  case 

[3861a]     of    1=1,     this  becomes,  as  in  [997],      -.Z."' — -^  =  —  A^^K       The   part     -^^     being 

introduced  by  the  tenn     -^^  .cos.  {n't  —  nt  -\- s'  —  s)     [954],  which  does  not  occur  in  the 

terms  noticed  in  the  value  of  R  [3858],   so  that  wherever  the  quantity      — ,  •^'',     occurs, 

[38616]     we  ought  to  add ;     or  in  other  words,    b        ought  to  be  increased  by  the  term , , 

fit  *  u  Ct 

or     —  a .        To   notice    this   circumstance,    we    must    apply    a   correction    to    the    vakie 


VI.  i.  §9.]  TERMS  OF  THE  FIFTH  ORDER  IN  e,  e,y.  13 

, ,          jti)     ,                         1  ,  .  ,    .  ,  ,T,n^  1        SOOe'^e 

we  must  add  to    b,    the  term =  ;     which  increases    a  N'-"'  by   -;.^  „  •      [3862] 

•i  a-*  763  a-^ 

This  behig    premised,    we    shall   multiply   the  preceding  values  of    a' N'-°\ 
a'iV''',     &c.    by    m',    and    shall    reduce    each    of   the    cosines    by   which 
they  are    multiplied    in    the    function    [3859],    into    sines    and    cosines    of      [38(32'] 
5  n't  —  2nt-{-5s — 2s;     Avhich  gives  to  this  function  the  following  form,* 

Value  of 

..'/?=      m'.a'P,.sm.(ôn't  —  2nt  +  5s'—2s)  «• 

[Action  of  m'  on  ml.  [38631 

+  m'.  a'  P;.  cos.  (5n't  —  2nt  +  5  s'—  2  e). 

We  shall  likewise  multiply  by   m    the  values  of    «'iV<%    rt'iV*'',    &c. 
relative  to  the  action  of  m  upon  m'  ;    and  shall  reduce  the  sines  and  cosines 


of      a' N'-'^''    [3860],    which   may   be   computed    by    supposing       II  =  —  a,       whicli 

(11  U) 

(Z  6  1  (id  h  jL 

gives     "^  =^ — 1)     "d'^'^^'    ^'^'       Substituting  these  in  [3860],  It  becomes 

_  '^  .  |_3138  a  + 13  a?  =  ^J^˱iîll ,  [3861c] 

/Uo  /Do 

as  in  [3361].     When  we  are  computing  the  action  of  m  on  m',  the  fonnula  [3861a]  becomes 

«        *         a-  a'   I    i         cfiS        a'   I     i                S' 

SO  that  the  correction  of    è^j'     is  — a-^,    and  the  correction  of   a'./V"'*   for  this  case,  will 

be  found  by  putting    &j  =  — a.--  in  the  expression  [3860].     Now  this  value  of  6  j  gives 

,,(1)                             (1)  (1)                                (1, 

substituting  these  in  that  expression  of    a' N  ^^\    it  becomes 

~ïml^-^~^^^^  —  ^  X  13  +  6  X1556  — 24  X  438  +  120  X  38  — 720}='|^, 
as  in  [3862]. 

*  (2436)    The  reduction  here  used  is  the  same  as  that   in   [3842J,  &c.],  by  which 
tiie  fonction   [3835]    is  reduced  to  the  form  of  [3842n'],  and  were  it  not  for  the  terms 
[3861,3862],  the  values  of   P,,  P/   [3863]  would  be  identical  with    P„,  P,,'  [3865], 
respectively  ;  for  the  factor  [3358]  is  the  same  for  both  planets  ;  and  the  reasoning  made     [3864a] 
use  of  in  [3846a— ^]  will  serve  to  prove,  in  [3863,  3865],  that  P,,  P/  will  be  respectively 
equal  to    P„,  P/,    if  we  neglect  the  ternis  [3361,3862],  and  we  shall  show,  in  [3866i],      [38646] 
that  these  ternis  do  not  affect  the  result. 
VOL.  III.  19 


74  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3864]      of  the  function  [3859]  to  sines  and  cosines  of      brilt  —  2/1^  +  5='  —  2;; 
which  will  give  to  it  the  following  form, 


Value  of 

R. 


'R  =      m  .  «'  P^,  .  sin.  (ôn't  —  2nt  +  ôs'—2s) 


[38651  [Action  of  «I  on  m']. 

^  +m.a'PJ.cos.(5n't  —  2nt  +  ôs'—2s). 

We  shall  then  substitute  these  values  successively,  in  the  expressions 
of  6v,  6v',  of  the  preceding  article  [3844,3846],  neglecting  their  second 
[3865']  differences,  because  of  the  smallness  of  these  quantities  ;  and  in  this 
way  we  shall  obtain  the  parts  of  the  inequalities  of  Jupiter  and  Saturn, 
corresponding  to  the  angle  5 n't  —  2nt,  and  depending  on  the  powers  and 
products  of  the  excentricities  and  inclinations  of  the  orbits  of  the  fifth  order. 

We  may  here  observe,   that  in  consequence  of  the   ratio  which  obtains 

[3806]      between  the  mean  motions  of  Jupiter  and  Saturn,  we  have    3125  a^^  500;* 

ji'  2  n'  **       4 

[3867]      for    a^==—    and    on'   is  very  nearly  equal  to  2n;    consequently   ■- ^  =  — . 

71"  11"  /Co 

Hence  it  follows,  that  the  value  of  a'  N  *°^  is  the  same,  ivhether  ice  consider 
the  action  of  m'  upon  in,  or  that  of  m  upon  m'.  Hence  we  may  deduce 
the  preceding  part  of   6  v'  from  the  corresponding  part  of  6  v,  by  multiplying 

[3868]      the  latter  by      —  ^J'~  .  -.f 


[3806a] 


[38666] 


[3868a] 


[38686] 


*  (24.37)    We  have  nearly    l=7v^a^  =  n"' a' ^  [3109'];  hence   iL.=-^^=:a3  [,38296]  ; 

n'       2  /n'\2       4 

but  by  [3318f/],  we  have  nearly    5n'  —  271^=0,    or    -  =  -;    therefore    a^=(-)=— , 

31  O  \7l  /  fit) 

as  in  [3867],  and    3125a^  =  500,    or    3125  a  = '—j- ;    substitutmg  this  in  the  increment 

of  a'JV^"'  [3861],  correspondmg  to  the  action  of  rn!  upon  m,  it  changes  into  the 
expression  [3862],  representing  the  increment  of  «'JV'"'  in  the  action  of  m  upon  m', 
as  we  have  remarked  in  [38646]. 

■j-  (2438)    If  we  multiply  the  factor     — '— — -  ,      connected   with   the  chief  term 

[an' — 2  rap 

of  ^t;  [-3844],  by  tlie  quantity     —  ^    '   „  .  -     [3868],  the  product  becomes 

im.n-     a     ^ 

\5m.n"^      a'         15m.n'~       1 


(5n'— 2>!)3  ■  a  ~  (5n'— 2n)3  '  a  ' 

j  the  same  as  the  corresponding  fac 

the  other  part,    -,    being  multiplied  into  the  terms    aP,   aP',  adP,   adP',  kc.  [-3844], 


in  which  the  part  — —  is  the  same  as  the  corresponding:  factor  of  the  terms  of  i5  y'  [3846]  ; 

(on — 2n)3  X  o 


VI.  i.  §10.]  TERMS  OF  THE  THIRD  ORDER  IN  MERCURY.  75 

10.    In  the  theory  of  Mercury  disturbed  by  the  Earth,  we  must  notice  the 

ine([uulity  depending  on  the  angle     nt  —  4  n7  ;     because  the  mean  motion  [3869] 

of  Mercury  is  very  nearly  four  times  that  of  the  Earth  [4077a].      Supposing  inequaiuv 

m  to  be  Mercury  and  m'  the  Earth,  we  shall  obtain  the  proposed  inequality  Siércuô" 

by  putting     i  =  4,     in  the   expression   oi    àv     [3817].       Considering  the  [3870] 

extreme    minuteness   of    this    inequality,    we   may   neglect    all    the    terms 

dP     (IP' 
depending  071    -r-,   ^— ,    and  retain  only  those  having  the  divisor   (n— 4?i'/.      [3871] 

Hence  we  shall  get* 

iv  =  ,    "'•""    .iaP'.sin.fa^— 4rt'^  +  s— 40+«P-cos.r?z^— 4n'^  +  -— 40i-      [3872] 
(«  —  Any    '  ^  ^  '  ' 

We  can  easily  determine    P    and  P'   in  the  following  manner.      We  may 

T  S  T 

calculate,   by  formula   [3711],    the  value  of      — g-,     corresponding  to  the 

angle     -I  n't  —  2nt,      by   substituting  in  it    i  :=  4.       Hence  we  obtain  a      [3873] 

value  of    —5-     of  the  form,t 
«- 

^-:       L  .  e^cos.  (4n'i  — 2nf  +  4s'  — 2e  — 2w) 

+  L"'.ee'.  cos.  (4n'«  — 2w^  +  4s'  — 2s  — ^  — ^') 
+  U^K  e'K  cos.  (4  n't  — 2  n  ^  +  4  s'  —  2 s—  2  ^') 
+  U^\  y"~ .  cos.  (4 n't  —  2n ^  +  4s'  — 2 £  —  2  n). 

We  shall  then  observe,  that  this  value  of     ^     results  from  the  variations 

(r 

of  the  excentricity  and  perihelion,  depending  on    nt  —  4<n't,    in  the  elliptical 


[3874] 


produces  the  corresponding  expressions  a  P,  a  P,  a'  d  P,  a  d  P',  he.  [3846]  ;  the 
values  P,  P'  of  S  v',  having  been  proved  in  the  two  last  notes  to  be  respectively  equal 
to  those  of   P,  P',   in   S  v. 


[3868c] 


*  (2439)    Neglecting    dP,   dP',   ddP,   ddP,    and  H,  in  [3817],  and  putting  z'=4,     [3872a] 
we  obtain  the  expression  [3872]. 

t  (2440)    The  two  first  of  the  angles  [3874],  connected  with    e^,  e  e',    are  explicitly 
contained  in  [3711]  ;  the  others,  as  well  as  these  two,  are  included  in  the  form 

cos.  \i  .{n't  —  nt-[-  s—  s)'\-2nt-\-  K\,  [3873o] 

which  occurs  in  [3711],  and  is  developed  in  [3745 — 3745'"]. 


76  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3875]      expression  of   ^.—  .     This  expression  contains  the  term    — c.cos.  (n/+;— cî), 
whose  variation  is* 

T  Ô  T 

[3876]  — ^  =  —  èe  .  cos.  (n  Ï  +  s  —  ra)  —  eôzs .  sin.  (n t  -\- s  —  ûî)  ; 

6e    and    (5w    being  the  variations  of   e    and    ^3,    depending  on    7i  t — i'li't. 


[3876c] 


*  (2441)    If  we  square  the  value  of  r  [3701],  and  substitute 

cos.^  {7it  -\-  e  —  ■ui)=zi  -\-^  COS.  '2.{nt  -\-s  —  k), 


we  shall  get 

r3=a2.{l  +  f  c^— 2c.cos.(ji?+s— to)  — ie-.cos.a.Cnf  +  e  — ro)  +  &;c.|. 


[3876rt] 

In  the  troubled  orbit  the  elements     r,  a,  e,  s,   ss,   n  t,     are  increased  by   the  variations 

[38766]     'J'';   <5  «)  Se,  Sis,    Sv,     respectively;    and  if  we  neglect  the  squares  and  products  of  these 

variations,  the  increment  of  the  preceding  expression  will  be  found  by  taking  its  differential 

relatively  to  the  characteristic  S  ;    hence  we  get 


2riir='iaôa.\l-lr§  c^—  &,c.  \ 

-j-  a-.  \3  c  5  c  —  2(Se.  cos.  («<-)-£  —  ûj)  —  2  c  ô  a  .  sin.  {n  t  -\-  s  —  zs)  —  &c. } . 

Dividing  this  by     9  a^,     it  becomes  of  the  form 

r  0 1' 
[3876rf]  — 2  =  —  Se.  cos.  {nt-\-  s  —  to)  —  e  f5  to  .  sin.  {n  t -{- s  —  to)  -(-  X  ; 

representing,  for  brevity,  by  the  symbol  X,  all  the  terms  of  the  second  member,  excepting 

the  two  parts  explicitly  retained  by  the  author  in  [38T6].      If  we  neglect  X,  and  substitute 

'-■    '*''•'     in  the  remaining  terms  the  values  of    Se,    e  o  a    [3877,  3878],  we  sbal]  get  the  expression 

of    —    [3879],  which  the  author  supposes  to  be  identical  with  [3874],  and  thence  by 

integration  obtains  Sv  [3882].  In  the  Memoirs  of  the  Astronomical  Society  of  London, 
Vol.  II,  page  358,  Sic,  Mr.  Plana  has  pointed  out  some  defects  in  this  method,  and  ha? 
shown,  that  the  terms  depending  on  X  materially  alter  the  result.  To  prove  this,  he  has 
computed  directly  the  terms  of  Sv  depending  on  the  divisor  [n — 4  n')^,  using  formulas 
similar  to  those  in  [3335 — 3841]  ;  which  we  shall  give  in  [3881r — w']  ;   after  going  over 

[.3876?]  the  calculation  by  the  method  of  the  author.  From  the  comparison  made  in  [3883w,  y], 
it  appears,  that  this  method  of  La  Place  cannot  be  considered,  in  an  analytical  point 
of  view,   as  a  very  near  approximation  to  the  truth  ;    though   he  seems  rather  unwilling 

[3876/t]  to  admit  the  fact,  in  a  note  he  published  on  the  subject  in  the  Connaisance  des  Terns, 
for  1829,  page  249. 


[3876/] 


VI.  i.  §10.]         TERMS  OF  THE  THIRD  ORDER  IN  MERCURY.  77 

We  shall  have,  by  [1288,  1297],* 

ôe=   __     ,■<     i  j^j.sm.  {4nt—nt -{-As  — i)-\-l--- ).  COS.  {in' t  —  nt-\-4£— s)Ç;  [3877] 

y  COS.  (4  n't  —  nt+4  s'—  s)  +  ('^^  .  sin .  {4n't  —  ni -{-é^—s)l;  [3878] 


yn'.an     C       /d  P 

e  0  a  = j— , .  <  —  I  -^ 

n  —  4  H    ^      \  a  e 

hence  the  variation  of    — e.cos. (ni  +  ' — ^)    becomesf 

r^r        m'.a?i    Ç/dP 


:£;^,.j('^).sin.(2n<-4n'i+2£-4£'-«)  — ('^Vcos.(3n<-4n'<-f2s-4£'-î:r)l.       [3879] 


This  function  is  identical  with  the  preceding  expression  of    -y    [3874]  ; 

therefore  if  we  change,  in  both  of  them,    2nt-\-2s    into    » ^  +  s  +  ^  +  - ,      [3880] 
V  being  the  semi-circumference,  we  shall  obtain  J 

T-;-  ^   -T-  ).cos.rwi — 4w'^+£ — 4/)+    ^—  ) .  sm.  (îi^ — 4n'i  +  £ — 4s')^ 

M — 4w     i\de/  ^       \de  J  ^  ') 

=      L  .  e^sin.  (4w'i  — wi  +  4E'  — 5  — 3ot) 

+  L"  '.  e  e'.  sin.  (4  m'  i  —  n  i  +  4  a'  —  s  —  î^' — 2  ^)  [3881] 

+  L(=>.e'^sin.  (4?j'^  — n^+4a'  — s  — 2a'  — w) 
+  L'^>.7-.sin.  (4n7— >i^  +  4s'  — E  — 73  — 2n). 


[3877o] 


[3879o] 


*  (2442)  The  expression  of  R  [12S7]  is  the  same  as  in  [.3810]  ;  so  that  P,  P'  have 
the  same  values  in  both  formulas.  Now  putting  t'  =  4,  »  =  1,  (j.=  1  [-3709],  in  the 
expression  of  à -a  [1297],  and  then  multiplying  it  by  e,  we  get  the  value  of  e5a  [3878]. 
The  variation  i5e  [1288]  becomes,  by  similar  substitutions,  of  the  same  form  as  in  [3S77]. 

t  (2443)  Putting,  for  a  moment,  Ati!  t —  nt -\- A^ — s^rT^,  nt-\-e  —  -^s^zW; 
then  multiplying   [387'i]  by      — cos.  ?r,     also   [3878]    by     — sin.  ?r,     and  adding  the 

J*  6  J* 
products,  we  get  for  the  second  member  of  [3876],  or  the  value  of     —^  ,     the  expression 

[3879e]  ;    reducing  this  by  means  of  [22,  24]    Int.,  it  becomes  as  in    [3879c],  which 
is  equivalent  to  [3879]  ; 

'■^='^^,-\(^)-i-sm.T,.cos.W+cos.T,.sm.JV}-(^\{^^^^  [38796] 

t  (2444)  We  have  two  expressions  of  —  [3874,  3879],  depending  upon  the 
angle     2nt  —  Aii't,     and  it  is  evident,  that  if  it  were  not  for  the  terms  produced  by  the 

VOL.  Ill,  20 


78  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[38S1']     If  we  integrate  this  equation  relatively  to  e,*  and  then  multiply  it  by 


11 — An 


we  shall  obtain 

I\L   .  eKsin.(4^n't  —  nt-\-4,£'  —  s  —  3^) 
+  1LW.  e^e'.  sin.  (4n'ï  — ni  +  4s'  — ;  — ^'  — 2^) 
+    L(^'.  ee'~.  sin.  (4  n'^  —  Ji  ^  +  4 s'  —  s  —  2  ^'  —  ^) 
+     L<^'.  ey-.sin.  (4n'/  — wi +4£'  — s  — ^  — 2  n) 

function  X  [3876e],  they  would  be  identical  ;  therefore  they  will  still  be  equal  to  each  other, 

if  we  change  the  angle     2nt-\-2e     into     7it-{-e-\--s-\-^ir.      Now  if  we  make  this  change 

in  [38741,  we  shall  find,  that  a  term  of  the  form    cos.(4n't—2?ii-\-'ie' — 2s4-A),    becomes 
[38806]  L         J' 

cos.{An't—nt-\-4£'  —  i-{-A  —  zi  —  i  •r)  =^  sin.  (4  7i' t  —  n  t -\- 4  ('  —  s-\-A  —  ■si); 

and  the  second  member  of  the  expression  [3874]  changes  into  the  second  member  of  [3881]. 
In  like  manner,     sin.  (2  ?i  ( — 4 n't -{-2  s  —  4  s' — w)     becomes 

[.3880c]  sin.  {nt  —  4  n'  t  -\-  s  —■  4  s'  -\-  ^v)  —  cos.  {nt  —  47i't-{-i  —  4s); 

and     COS.  {2nt  —  4n't  -\-2s  —  4  s' —  «)     becomes 
[3880d]  COS.  {n  t—4n't-\-s  —  4  s'+  è  *)  =  —sin.  {nt —  4  n't -\-s  —  4  s')  ; 

hence  the  second  member  of  [3879]  becomes  as  in  the  first  member  of  [3881]. 

*  (2445)    Multiplying  the  equation  [3881]  by   de,    and  then  integrating  it  relatively 
to   e,   in  order  to  obtain  the  values  of  P,  P',   we  get 

J!!Î:^Ap.co5.(nt  —  47i't-\-B  —  4s')-\-P'.sm.{nt  —  47i't^s  —  4s')\ 
n— 4n'     i  > 

=      iL    .  e^  .sm.{4n't  —  nt-{-4s  —  s  —  3-a) 

[38816]  +  i  L^^'.  e^  e'.  sin.  {4n't  —  nt-\-4  s'—  s  —  u'—  2  ra) 

+    L<2'.  ee'2.  sin.  (4  7i't  —  n  <  +  4  e'—  £  —  2^—  tn) 

-}-     L'-^1.ey^.sm.{4n't  —  nt-\-4e  —  s  —  -us  —  2n). 

3n 
The  first  member  of  this  expression  being  multiplied  by        _     , ,     becomes  equal  to  the 

value  0Î  Sv   [3872]  ;    therefore    5  v    will  be  obtained  by  multiplying  the  second  member 

[3881c]     of  [38816]  by     — —  ;     and  in  this  way  we  obtain  [3882].      In  the  integration  relative 

to   e   [3881a,  6],  we  may  add  terms   depending  on    e'^,    and    e 'f,    which  are  considered 

as  constant  in  the  integrations  ;   but  the   excentricity  of  the   Earth's   orbit    e',   being  only 

[3881rf]    about  -rV  of  e    [4080],   the  term  depending   on    e'^,    must  be  much  smaller   tlian   the 


VI.  i.  §10.]  TERMS  OF  THE  THIRD  ORDER  IN  MERCURY.  79 

In   this    integration,    we  neglect  the   terms  of    P    and    P'    depending  on     [3882] 


[3881e] 


[3881/] 


others  ;  and  the  same  remark  will  apply  to  the  term  depending  on  e'  7^.  The  author 
has  neglected  these  terms,  because  they  are  so  much  less  than  those  which  are  included 
in  the  expression  [3882]. 

Having  followed  the  author  in  this  indirect  method  of  computing  the  value  of  <^v  [3882], 
we  shall  now  proceed  to  the  direct  investigation  of  the  same  inequality.  For  this  purpose 
we  must  have  an  expression  of  R,  similar  to  [3835],  depending  on  the  angle  4  ti!  t  —  nt. 
This  expression  is  evidently  of  the  following  form, 

R  =      M«»  .  e"  .  COS.  (4  71 1  —  71 1  +  4  e'—  s  —  3  z>') 

+  Jtf  "' .  c'^e .  COS.  (4  ?i'<  —  ?i  <  -f-  4  e'—  s  —  2  ra'—  -55) 
+  M'-> .  e'  c2 .  COS.  {An't  — 71 1-{- 4  s'—  s  _  ra'—  2  ts) 
+  JU"'.  e»  .COS.  (4?i'<  — ?8/  +  4£'— £  — 3«) 
+  JJf  («.  e'  f.  COS.  (4  n'<  —  ?U  +  4  e'—  s  —  a'—  2  n) 
-\-M^^\ey^.  COS.  {A7i't  —  7it-\-4^—s  —  zs—2n); 

but  the  factors  JW«>,  M'-^\    he.  are  different  from  those  in  [3836,  Sic]  ;    we  shall  give 

their  values   in   [3S8lr — !«'].      If  we  suppose,  for  a  moment,  the   preceding  expression 

of    R    to  be  put  under  the   form      R=  2  M  .cos.  {4  n't— Tit -{- K),      we   shall    have 

d  JÎ  =  )!  2  M .  sin.  {4  n't  —  nt  +  K)    [916'].       Substituting  this  in  the  expression  of  the  ^^ 

mean  longitude   ^    [3715/],  we  shall  get  the  corresponding  term, 

Sv  =  3rrandt.àR=  —  -^^„.:sM.sm.(4n't  —  nt-i-K);  [388U] 

•'''  [4n'—nf 

therefore  the  value  of   5v    may  be  easily  derived  from    R    [38S1/],   by  multiplying  it 

by ; ,     and  changing  the  cosi7ies  into  sines.      The  terms  of  jR   may  be  very      [3881il 

easily  obtained  from  the  values  of   Jkf'"',  M'-^\  he,  computed  in  [3836(7— 3840o],  by 

merely  decreasing  the  value  of  i   by  unity  ;    so  as  to  change   the   angle     5  n't  —  2  7it 

into     4 n't  —  nt.      In  this  way  of  computing    M'-°\    we  must  use  the  decreased  value 

i=\    [3836a],   and  then  [3836(Z]   becomes  as  in   [3881r].       In  computing  .M"'  from      [3881/] 

[3837c],    we   have   the   decreased   value      i^2    [3837a];     hence   we   get    [3881s].     [.3881jn] 

From  [3838e,  A],  we  get  the  decreased  value    i=3,   and  JF-'  [38810-     From  [3839«,  b],     [3881n] 

we  get  the  decreased  value    i  =  4,   and  M'^' [3881m].      These  expressions  are  reduced,  in     rgggj  ^ 

the  fii-st  place,  by  means  of  the  formulas  [1003],  and  then  by  [996—1001]  ;  so  that  we  finally 

obtain  the  values  [3881r',  s',  t',  u'].      Observing,  that  in  computing  JIf  '  [3881/],  we  must 

(1) 

notice  the  increments  of      6,      and ,    represented  by    — a   and    — 1,    respectively,     [3881o] 

'  da. 

as   in    [38616 — c],  by  which  means  we  shall  obtain  the   first  term,      — —,.\—256o.l, 


[S88U] 


80  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

[3883]      e'^  and  e' y- \   but  as  the  excentricity  of  the  orbit  of  the  Earth  is  quite  small, 

in  the  expression  [388 b'J,  which  is  omitted  by  Mr.  Plana  by  mistake.  In  like  manner, 
[3881o']  from  [3840Â]  and  the  decreased  value  z  — 3  [3840^],  we  obtain  Jl/™  [.3881  «]  ;  also  from 
[3881;>]     [3840rt]  and  the  decreased  value  i=A    [3840m],  we  obtain    M'^)   [388 1  w]  ;  which,  by 

similar  substitutions  [1008,  Sic],  are  reduced  to  the  forms  [3831t)',  w'].     In  making  these 

[3881?]     successive  reductions,  we  have  used  the  abridged  expression  [3755a],     ./2 '"=«'" 


'3        

rfa'3 


[3881.]  JIf  .0,^       ^  .  564^<"-48«'.  C-f^)  +  12«-.  f'-^Ua' 

48      ^  \da'  J    ^  V  f'a'-  / 

^^,      C64^'i>  +  48.[^'»  +  ^/')]  +  12.[2^("  +  4^/»  +  ^3W] 

"^^'1  +  [6.^W+18^i(')+9.^a<"+^3("] 

=      J  .  ^  14-2  ^'"+114^/"+ 21  ^3<'> +^3(1' I 


,0)  (1)  (IV 


[3881,-']  =       -^    5_256a+142è!'  +  114a.'^  +  21a^   '"' ^  ^^-^    '''' ' 


104^^-'  +  26a.(^)-40«'.('if!^Ul0a'«.r^^ 
\  da  J  \da  /  \dadaj 

104  ^'2)  _^  26  ^^(2) _j_  40  .  |-^(2) _|.  ^^(3)-j  _^  10  .  [2  ^/2)  ^  ^  ® ■] 
+  4  .  [2^«>+  4  ^p  +  ^2^2,-]  _|.  |-6 ^^(2)+  6^3(2)+  ^3« 
152^«)_)_  108  ^  ®_|_  20  ^3'2i_^  _^^c3)^ 


[3881«]  J/(i>  =  — -. 


16 


ÏG 


(S)  <2)  .„,(2)  __(2) 


[3881(]  3f(2)^       ^ 


[3881,']  =      J!-,.jl526r+108a.liL  +  20a2.^+a3.^ii 

'-•«"'--«■•C^')+-«-(^')--«-G^) 

C  126^"^+  21  .  [^(3)+  ^  ffl-|  ^  60  ^/='+  10  .  [2  ^/3'  +  ^2i3)j 

(+6^3^=1+  [3  ^2"'+^3'3>] 

I  147  ^'■»+  101  ^  o)_|.  19  ^^(3) _^  _^^C3,| 


ÏG 

m' 
16 


,        C  „v  (3)  (3)  (3) 

[3881f  ]  =  _  -^, .  j  147  6,  + 101  a .  !iil-  +  19  a=2.  ^  +  a^.  ^^  ; 


VI.  i.  §10.]  TERMS  OF  THE  THIRD  ORDER  IN  MERCURY.  81 

in  comparison  with  that  of  Mercury,  and  the  inequality  in  question  is  very     [388!?] 

f  (4)  (4)  (4)  -J 

..».=   |....^_5B».+..(i^)^='^...,.^-5««+[-3i,...-„(';£:>)] 

IG  t  '  \  da    J)  W    o'    C        f    '  da.   ^' 


[3881t)] 


[3881w'] 


JIf  (5)=       -^.  a'a .  ^  5  B®  +  «  .  (  — )  (■  [3881i<;] 

I  5  6  3  4-  a  .  -—^  C  •  L'^ooiw)  j 


16  "  a'  ■  C         ^  '/■^ 

(1) 
rfSfe. 

If  we  substitute  in  these  the  numerical  vahies  [409.5 — 4102'!,  also       ^  =  5,340815, 

da? 

(2) 

a.-^-^^  1,96112,      given  by  Mr.  Plana,  in  Vol.  II,  page  366,  of  the  Memoirs  of  the 
Astronomical  Society  of  London,  we  shall  obtain,  by  supposing    «'=1, 

a' JH'0'=  —  m'.  0,-3411;         a'JW*'>=       m'.3,3192;         a' M'2'=  _m'.  1,4808  ; 
o'J»f(3i==       m'.0,2181;         a'JJf  ^4' =  —  >«'.  0,1921  ;         a'^®^       m'.  0,0690. 


[3883a] 


[38836] 


The  last  four  of  these  numbers  agree  nearly  with  those  given  by  Mr.  Plana;  but  he 
finds  «']»/<«'  =  — m'.  2,40567,  a'.y»f(»  =  m'.  2,94.30  ;  so  that  he  makes  .M'"'  seven  [3883c] 
times  too  great,  and  .Af  <"  about  a  seventh  part  too  small.  The  first  of  these  mistakes 
arises  from  the  omission  of  the  term  —  256  a  [388  lo]  ;  the  second  is  an  error  in  the 
numerical  calculations.  We  must  observe,  that  the  indices  of  M  in  La  Place's 
notation,  namely,  0,  1,  2,  3,  4,  5,  correspond,  respectively,  to  3,  2,  1,  0,  5,  4,  in  [3883d] 
the  notation  used  by  Mr.  Plana.  In  computing  the  value  of  5  v,  Mr.  Plana  uses  the 
elements  coiTesponding  to  the  year  1800,  namely, 

e'=  0,0163.5.32;         e  =  0,2056163;      7  =  tang.  7' 0"  6' ;  w' =  99'^ 30™  5' ; 

[3883e] 


«=74'' 21™  47^;       n  =  4.5''.57"'3P  ;      «'=1;       «  =  0,.38709;     and     ?i',  w  [4077]  ; 

.329630     t^^^^3      '"^       35^36' 


he    also    reduces    the    mass     m'    from      .JoqV^     [4061]      to  ^,       which    makes     [3883/] 


VOL.  Ill,  21 


82  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Céî. 

[3883"]     small,  we   may  neglect  these   terms  without  any  sensible   error    [388 Id]. 

H."=— 0,0713  [42.30'];  then  by  the  method  [3881  î],  he  finally  obtains 

[3883g-]  6v  =  0^5596  .  sin.  {4:n't  —  nt-\-4s  —  i—l6''  59"  20"). 

If  we  correct  the  errors  mentioned  in  [3883c]  ;  also  another  error,  in  his  substitution  of  the 
value  of   2  n,   which  is  taken  too  small  by  40'',  in  [3881/]  ;  it  will  become 

[3883^]  Sv  =  0',61 .  sin.  {An't  —  nt-^-A  s  —  s  —  21''  19"=). 

This  differs  but  very  little  from  the  computation  of  La  Place  in  [4283],  namely, 

ôv  =  (1  +|x")  .  0',69  .  sin.  {4n"t—nt-\-4^'—s~19^2'^  1.3') 
[3883t] 

=  0-',64  .  sin.  (4  n"  <  —  71  f  +  4  e"—  s  —  Id''  2'"  13')         [3883/]. 

Notwithstanding  this  near  agreement  in  the  numerical  results,  the  method  of  La  Place  is 
essentially  defective,  as  may  be  seen  by  comparing  the  term  depending  on  e^  in  the 
expression  [3881i,/],  namely, 

[3883i]  Sv  =  —~~  .  JJf  (31.  c».  sin.  (4  n't  —  nt-}-4s'—s  —  3  o), 

with  that  given  by  La  Place  in  [3882], 

t-'^'^^^']  ê  V  ==      ".   , .  L  .  c^.sin.  (4n't  —  n  t  +  41'—  s  —  3z:). 

[38S3n     To  compute  the  value  of  L,  we  may  observe,  that    L.ë'.cos.{4n't—2nt-{-4e'—2B  —  2zs) 

is  the  term  of      ~,     depending  on    e~,    in  [38741.       Now  the  term   of     —    [3711], 
[3883m]  ai  ^  ^  a'^      <-  ■> 

corresponding  to   i=4,   and  having  the  divisor   4n  —  n,    is 


[388.3n]  4'l?3^-«-^^+«-(77' 


-r-  .  a  Jli 4-  a^.[—-) 

-rpL ,       \?±J  .  n^.  COS.  (4  n'<  — 2m  <  +  4  s'—  2  5  — 2  s) 

(4n  — î!.).(4n— 3n)  ^  '  '  ■ 


and  as  we   retain  here    only  the   terms  depending    on    c^,    we  may  put     M^=M^^'^  e^ 
[.3703,3745];  moreover,  we  have,  in  the  present  case,  very  nearly     4  ?i'  —  2n  =  — n, 

4n' —  3n  =  —  2n    [3869]  ;     hence  this  term  of    ^     becomes 

\4aM-^+a^.('-^\\ 
[38830]  _(__ \  da    /),nc'.cos.{4  7H  —  2jit  +  4i'—2s  —  2^). 

2.(4J^'— n)  ^  '  ' 

Now  we  may  obtain  the  expression  of  M'"'  [3S8.3p],  by  putting  i=^4  [3883m],  in  [3750], 
The   partial  differential,  relative  to   a,   is  as  in    [38837].       Substituting   these  two  values 


VI.  i.  §11.]      TERMS  OF  THE  SECOND  ORDER  IN  THE  LATITUDE.  83 

11.     It  follows,  from  [1337'— 1342],  that  the  two  terms  of  R  [3835], 
represented  by 

R=      M^*K  e'  r.  COS.  (5  n't  — 2n  t  +  5  s'  —  2s  — zs'—2n) 

[3884] 
+  M^'\e  f- cos.(5  n't  — 2ni +  5  s'  — 2s  — z:  —  2n), 


in  the  first  member  of  [3883;-],  and  making  the  same  reductions  as  in  [999,  &c.].  we 
get  [3S83«],  by  putting    «'=1, 

r  (4)  (4)  (4)  \ 

= —  .)176è    +n4a.-— 4-20a^. -j-^+a^.-— --(  .  [3883*] 

Substituting  this  in  [3883o],  and  putting  the  resuk  equal  to 

L  .  e^  COS.  (4  n'  i;  —  2  »  ^  -f-  4  £'—  2  c-  —  2  tn)         [3883Z'], 
vre  get 

r  (4)  (4)  (4)  -s 

L^^:^       176è';+114a.^  +  20a^Çf +  a3.^%    ;  [3883^ 

16.(4)1  — n)    C  2^  da.     '  dofi  da-'    )  "■  J 

consequently  the  part  of  5v    [3883?],  computed  by  La  Place,  is 

C  (4^  (4)  W  5 

16. (-In'— nf    (  5-    '  da.      '  daS    ^         rfaS    V 

whereas  the  real  value,  obtained  by  the  direct  method  [3881i,  m'],  is 


3,  =  _"•"";•-"  „.^1.366l'  +  93a.^+18a^.^+a3.^^  [3883.] 


, ,  ,.   , r5  .  )  1.36  6  1  +  93 a .  -^  +  18 a^.  -7-^-  +  «-'•  -7—0 

10.(4,i'— n)2    (  4    '  da      '  da^      '  rf a^ 


If  we  substitute  in  these  expressions  the  values  given  in  [4095,  &c.],  we  shall  find,  that 

the  coefficient  of    —  — ^ '■ ,      in  the  first  is  12,  54,  and  in  the  second  10,  50;  so     [3883jc] 

16.  (4  n' — n)2 

that  La  Place's  method  makes  this  term  too  great  by  about  one  fifth  part  ;  and  the  same      [.3883i] 
discrepancy  occurs  in  the  coefficients  of  most  of  the  terms  of  these  two  formulas. 


84  PERTURBATIONS  OF  THE  PLANETS.  [Méc.  Cél. 

produce  in  the  value  of  s,  or  in  the  motion  of  m  in  latitude,  the  inequality,* 

[3885]  6  5  =  —  — -; — -  •  <  >  • 

5n  — 2?i     ^  _j_  3j(5)  _  f  ^  _  5;„_  (5  ,^/^  _3nt  +  5s'—3s  —  -a—n)  ) 

Moreover  the  same  terms  produce  in  the  value  of  s',   or  in  the  motion  of  m' 
in  latitude,  the  inequality  f 

2a'»'       m     S       ^''^•e'7-sin.(4n'<-2«^  +  4a'_2s-^'-n)^ 

[3886]  i  s  =  ■^, —  .  -  .  <  >  ; 

5n'— 2?J    m     (  j^  jyj^^K  ey  .  sm.  {47i' t—2n  t -\- 4  s'— 2  s —  zs —  n)  ) 


There  is  a  small  inequality  in  the  motion  of  the  Earth,  depending  on  the  same  angle 
nt  —  4.n"t,     given    by  the    author   in    [4311].       He   seems  to   have  computed    it  from 

[3883y]     the  term  for  Mercury  [4283],  hy  means  of  the  formula  [1208],      ôv"  =  —  5v.~^,, 

using     (5«  =  — 0',690412    [4283],  and  the  other  elements  [4061,  4079].      This  method 
will  answer,  as  the  inequality  is  extremely  small. 

*  (2446)    Putting;,  in  the  term  of  iî  [1337"],    tang.  9/ =  7,    it  becomes 
[.3885o] 

R  =  m  k  .  y^.  cos.  [i'  n' t  —  int  -\-  Jl  —  g  ()/)  ; 

[3885a']    comparing  this  with  [3884],  we  get      5"  =2,     d/ =  n,     j':=5,     i  =  2;      also  in  the 

first  term,     m'k  =  M^'^'^ .  e',    ^  =5  s' — 2  £  —  s/  ;    and  in  the  second  term,    mk  =  M^^'^.  e, 
[388561 

•'     i^  =  5  s' — 2  s  —  ro.      Substituting  these  in  [1342],  which  is  obtained  from  the  integrals 

[1341«,  1341],  we  obtain  in  s,  from  the  first  term,  the  quantity 

[3885c]  _-l^.J»fW).e'y.sin.(5rt'/-2«^-«  +  5  3'-2.-^'-n); 

and  from  the  second  term,  the  quantity 

[3885d]  --^^^^.M^'\cy.^m.{bnt-2nt-v-\-b^'-2^-^-U); 

observing,  that    (j,=:l    [3709].       Putting,  in  these,  for  v,  its  mean  value    nt-\-e  [3834], 
and  connecting  the  two  preceding  terms,  they  become  as  in  [3885]. 

t  (2447)    The  terms  of   R  [3884],  used  in  computing  s  [3885],  are  deduced    from 

the   fonction  [3831],  which  is  multiplied  by  the   factor  or  mass  m.       In  computing  the 

[3886o]     value  of  s' ,  corresponding  to  the  planet  m',    and  to  the  same  angles,  we  must  use  the 

factor  m,    instead  of  in  ;    therefore  the  value  of  R  to  be  used  in  computing  s',  is  equal 


to  the  function  [3884],  multiplied  by    —  ;     which  amounts  to  the  same  thing  as  to  change 
[38866]     M^^\   M^^\    into    — ,.JI/^",     and   —,.M^^\    respectively. 


VI.  i.  §11.]      TERMS  OF  THE  SECOND  ORDER  IN  THE  LATITUDE.  85 

n  being,   as  in  the  preceding  inequality  of  s,  the  longitude  of  the  ascending     rgggg,, 
node  of  the  orbit   of  in!   upon  that   of  m.      These  are   the   only   sensible 
inequalities  in  latitude,  in  the  planetary  system,  depending  on  the  product 
of  the  excentricities  and  inclinations  of  the  orbits. 

We  have   seen,  in   [3800],  that  the  value  of  5  s  produces  in  the  motion 
of  m,    reduced  to  the  fixed  plane,  the  term      —  tang.  ?  .  6  s  .  cos.  {i\ —  '')  ;      [3887] 
by  substituting  the  preceding  inequality  of  s  [3885]  in  this  term,  we  shall 
obtain  a  term  depending  on     bn't  —  2  n  ^ ,     which   must  be   added  to  the 


If  we  now  compare  the  value  of  s  [-3885]  with  the  vakie  of  R  [3884],  we  shall  find, 

that  s  may  be  derived  from  R,  by  multiplying  it  by    '■ —  ;     then  integrating  relatively     [388(;c] 

to  t,  as  in  [.38S5è,  &c.,  1341»],  and  after  integration,  decreasing  the  angles  by  the  quantity 

i'  —  n   [3885c],  or  by  its  mean  value    nt-\-s  — 11.      In  like  manner,  we  may  derive  s'     [3886rf] 

from  R  [3884],  after  multiplying  it  by  the  factor     ^     [38866].     This  value  of  ^,.il 
is  to  be  multiplied  by     — '- — ,     to  correspond  with  [3886c],  and  it  will  become 

„     (      JW<«.e'y.cos.  (.5?i'^  — 2?U  +  5£'— 2  e  — ra'  — 2n)) 
-2a'ri'.f/^.-,.^  >;  [3886e] 

-(-  JIf  ^5)_  e  y  _  COS.  (5  ?t'^  —  2  Ji  <  +  5  e'—  2  £  —  «  —  2  n)  ) 


m 


and  then  by  integration,  we  get 

2a' n'        m     <»       iV/«' .  e'"/ .  sin.  (5  n'^  —  2  71  i!  +  5  s'— 2  £  —  ^' —  2  n) 


5ji' — 2îi  '  m'  ' 


-\-  iW^s).  g  y  .  sin.  (5  „'^  _  3  „  i  _|_  5  £'_  2  c  _  js  —  2  n) 


[388(;c'l 


The  angles       bnt  —  2nt  + 5s' — ^2£  —  is  —  2n,    Sic,      must  now  be  decreased  by 

v  —  n'=nt-\-s' — n',      corresponding  to  the  planet  m',  as  in  [.3886c/];  the  angle  n' 

being  the  longitude  of  the  ascending  node  of  the  orbit  of  7n   upon  that  of  m'  ;    in  the  same     rsgsry] 

manner  as  n  [3746]  is  the  ascendirig  node  of  m'   upon   that  of   m  ;     and   it  is  evident, 

that     n'  =  180''  -f  n  ;      hence     v'—U'=n't-{-s'—n—  180"'.        Subtractmg  this  from 

the  angles  which  occur  in  [3886e'],  it  becomes 

9«'„'      ™     C       M^'^\e'y.sm.  (4n't  — 2  nt-{- As  — 2  s  — zj'—n  + ISO")) 


5«'_2n    m'    ^  _j_  J/(5)_  g  ^  ,  ^j,,,  (4  ^'^  _  2  „  ^  +  4  a' _  2  £_  «  _  n  +  180") 

which  is  easily  reduced  to  the  form  [3886]. 
VOL.  III.  22 


86  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Ce). 

g      great   inequality   of   the    motion   of    m;     but   this    term   is    insensible    for 
Jupiter  and  Saturn.* 


*  (2448)    The  functions    5  s,  ôs'    [3885,3886],  reduced  to  numbers  in  [4458,4513], 
[3887o]    j^j.g  Qf  jjjg  Qj.£jej.  3i  or  9'  ;   these  are  muhiphed  by   tang.  9   in  [3887],  and  as  this  tangent 
is  very  small  [4082],  these  terms  may  be  neglected. 


VI.  ii.  sU2.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  87 


CHAPTER   II. 

INEaUALITIES  DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE. 

12.  The  great  inequalities  which  toe  have  just  investigated,  prochice  other 
sensible  ones,  depending  on  the  square  of  the  disturbing  force.  We  have 
given  the  analytical  expressions  in  [1213,  1214,  1306 — 1309]  ;  and  it 
follows,  from  [1197,  1213],  that  if  we  put 

the  great  inequality  of  Jupiter  ^=  H.  sin.  (5 n't — 2nt  +  ÔB — 2s+  Â),  [38891 

we  shall  have  e^^juaiu!"; 

of  Jupiter. 

^^^_^.(^'»V«;+^"'V«).sin.2.(5u'^-2n^  +  5a'-2s  +  J),         [3890] 
8  m  ya 

for  the  corresponding  inequality  of  Jupiter,  depending  on  the  square  of  the 
disturbing  force*      This  inequality,  like  that  from  ivhich  it  is  derived,  is  to     [3890] 
be  added  to  the  mean  motion  of  Jupiter. 

In  like  manner,  if  we  put 
the  great  inequality  of  Saturn ^'= — ïï'. sin.  (5 n't — 2nt-\-ôs' — 2s+Z')»         [3891] 
we  shall  have  ^Sties 

of  Saturn. 

6v'=--.  ^- !^-—L )LJ  .  sm.  2.(5n't  —  2nt-i-5s'—2;+A),  [3891'] 

8  m  y  a  ^ 

*  (2449)  The  great  inequality  of  Jupiter  is  found,  by  substituting,  in  ^  [1197], 
,A=1    [.3709],    also    i  =  2,    i'=5;    and  if  we  put 

6m'.an^k 

^  =  5.^— 2e  +  :4,  T,=  5n't  —  2nt  +  5^  —  2s,  ^=— (5n'-2n)g'  ^^^^^''^ 

we  get      ^  =  H.sln.  (jr5  +  ;i),     as  in    [3889].       Making  the  same  substitutions  in   the     [3890c] 
terms  of  the  second  order  [121.3J,  it  becomes  as  in  [3890]. 


88 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


[3891"]    for  the  correspondmg  inequality  of  Saturn,*   which  must  be  added  to  the 
mean  motion  of  Saturn. 

The  variations  of  the  excentricities  and  perihelion  may  introduce  similar 

inequalities  in  the  mean  motions  of  the  tivo  planets.     To  determine  them, 

[3891"']     we  shall  ohserve,  that  if  we  notice  only  the   cubes   and  products  of  three 

dimensions,  of  the  excentricities  and  inclinations  of  the  orbits,  we  shall  havef 


[3892]      3a.ffndt.dR  =  —  Ga  m'.ff^i-  dt". 


P.cos.{5n't—2nt  +  5s'—2s) 
—  P'.  sin.  (5n'<~9n  t  +  5s'—2  s) 


[3891a] 


[3891&] 


[3891d] 


[3891e] 

[3892ol 
[38925] 

[3892c] 


*  (2150)    Substitutmg  ^  [3S90c]  in  [1208],  we  get 
the  great  inequality  of  Saturn  ^'  = 


mi/a    —    .      ,„    ,    _, 
-,.H.sm.{T.^-JrJl); 


m'  j/a' 
putting  tliis  equal  to  the  assumed  value  [3891],  we  obtain 

— ,       mv/o    _  _ 

H  =-—-,.  H,     and     jI  =  J1l. 
m\/a 

Now  by  comparing  the  two  formulas  [1213,  1214],  we   find,   that  the  part  of  the   great 
inequality  of  Saturn,   depending  on   the   square  of  the   disturliing  force,   is   equal    to  the 

m\/a 


[3891c]      corresponding  part  of  the  great  inequality  of  Jupiter,  multiplied  by       —    ,      ,  , 
using  the  expression  of  this  inequality  of  Jupiter  [3S90],  that  of  Saturn  becomes 


and  by 


_g    TOv/a     (2m'\/a'-\-5ms/a) 


m'  y/a! 


m't/a' 


sin.2.(7;+:5)^i^'-.'^-'^;^-^°Uin.2.(7;  +  :^); 


the  second  of  these  formulas  being  deduced  from  the  first,  by  the  substitution  of  H  [38916]. 
This  last  expression  agrees  with  that  in  [3891'],  except  that  Â  is  changed  into  JÎ',  so  as 
to  make  both  the  expressions  [3S91,  3891']  depend  on  the  same  argument;  observing, 
that  these  quantities  are  very  nearly  equal  to  each  other,  since,  in  the  year  17.50,  we  have 
^  =  4''22'"2P  [44.34],  and  .1'=  4'' 21'"  20"  [4492]. 

f  (2451)  The  part  of  R  depending  on  the  angle  Zn't  —  2nt,  and  terms  of  the 
third  degree  in  e,  c',  y,  h.c.,  is  given  in  [3842«'].  Its  differential,  relatively  to  the 
characteristic  d  [916'],  is 

àR  =  —  2nJ.ndt.\P.  cos.  %  —  P' .  sin.  %]. 

Multiplying  this  by  Za.ndi,  and  prefixing  the  double  sign  of  integration,  we  get  [3892], 
which  represents  the  part  of  5v  [3715i],  depending  on  diî,  the  divisor  \/(l — e®)  being 
neglected,  as  in  [3718'].  The  quantities  P,  P',  which  occur  in  this  expression,  are,  given 
in  [3842,  3843],  in  terms  of  the  elements  of  the  orbits  of  m,  m'. 


VI.  il.  §1-2.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  89 

which  gives,  in    3  a  .ffn  d  t .  d  R,    the  quantity* 

àe-\(j-)-C03.[57it—2nt+5s'—2B)—{'—-\sm.{5n'l-2ntj-5s'—'is)l 
+  0  75.  J  (-—^  . cos.(Mt—2nt-^5£'—2s)-r—-Ymn.(5n'l-Qnt+5s'—2 s)l 

+  de'.  }('~ycos.{Wt-'2nti-5e'-2s)~Çj^\sm.{5n't--'2nt+5s'—2s). 

-Qam'.ffn\W.(  );  [3893] 

y+6ra'.  j  ('y-Vcos.lSn'f— 2jie+5c-'— 2e)— f— Vsin.(5n'<— 2?U+5s'— 25);  / 

-^5  y.  j  r_-yco3.(5)i'<— 2;i<+5£'— 2=)— ^j- Vsin.(5ra'«— 2(!<-(-5s'— 2;)^ 

^+5n.  \{j^  •  '=°^-  (ô«'«-2n/+5s'-2;)-(^^)  .sin.(5n'<-2n<+5='-2.=)|^ 

6e,  6 a,  6e',  6^',  6),  6U,    being  the  parts  of    e,  ra,  e',  ra',  7,  n,    respectively, 
depending  upon  the  angle    5n't  —  2nt.      We  have,  by  means  of  [3842c], f 

/dP\  fdP'\  /dP'\  /'dP\ 

[j^)-'-[j7)'  W;=-^-(rfrj'  [3894] 

/dP\         ,  /dP'\  /dP'\  ,  fdP\ 

*  (2452)  We  have  already  noticed  the  effect  of  the  secular  variations  of  P,  P',  in  the 
terms  of  3a.ffndt.dR  [3812,3812/],  depending  on  sin.Tj,  cos.Tj;  using,  for  brevity, 
T5  [38906].  The  object  of  the  present  investigation  is  to  ascertain  whether  the  periodical 
variations  of  e,  e',  to,  -as',  r,  n,  depending  on  the  angle  T5,  which  are  computed  in  [3893a] 
[1288,  1297,  Sic],  produce,  in  the  function  3  a  .ffndt .  dR,  any  secular  or  periodical 
inequaUties.  Now  if  we  suppose  the  elements  e,  e',  w,  -ra',  /,  II,  to  be  increased  by  the 
variations  5e,  &e',  S-a,  ôts,  Sy,  Su,  respectively,  the  corresponding  increments  of  P,  P', 
will  be  obtained,  by  means  of  [607 — 612],  in  the  following  forms, 

these   parts  of  the  general  values  of   P,  P',    being  substituted   in   [3892],  produce  the 
expression  [3893]. 

t  (2453)    The  equations  [3894 — 3894"],  are  easily  deduced  from  the  general  values 
VOL.  III.  23 


90  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

Moreover  we  have,  as  in  [1297,  1288],* 
[3895]      (— Vco3.(5«'i-2n^  +  5£'-26)-('^Vsin.(5n'^-2n/+5£'-26)=     '^"^]~^^"lerî^; 

[3895']      (^).cos.(5«V-2?ii  +  5s'~2£)+('^Vsin.(5n7-2ni+5£'-2e)  =  -'^^7^.<5e; 
we  likewise  havef 

[3896]       (~\.cos.{^n't~2nt  +  bi-2s)  —  (^\.Bm.(bn't-2nt+b^-^i)=    ''^"'^"le'cî^^: 
\dc' J  '       \de:  J  ^  '  ^  m.a'n'  ' 

[3896']      (^).cos.(5n't-2nt  +  5s'-2s)4-('^).s[n.(57i't-2}it4-5B'—2e)=-^^^^^^^^ 
\"6/  '       \de  /  ^  '  m.an 

of  P,  P'  [.3S42c],  which  give 
[38940]  (^\  =  2  è  .  JJi'.  e'".  e*.  y^'.  cos.  (6V+  &  ra  +  2  c  n)  ; 

[38946]  (^— 'j=:2&.iVf'.e"''.e''-^y'^^cos.(i'îï'  +  6w4-2cn). 

These  expressions  satisfy  the  first  of  the  equations  [3894]  ;  and  in  hke  manner,  we  may  prove 
the  others  to  be  accurate,  by  the  substitution  of  the  partial  differentials  of  P,  P'  [3842c]. 

*    (2454)     The   value   of    R    [3842a'],    is   the    same   as    that   assumed  in    [1287], 
[3S95o]     supposing    (*=!,    i' ■=b,    i  =  2,    as  in    [3890«].      Making  the   same  substitutions   in 
ÔC,   i5a   [1288,  1297],  we  get,  by  using  the  abridged  symbols  [3846^,(1],  the  following 
expressions,  which  are  easily  reduced  to  the  forms  [3895',  3895]  ; 


[3895i] 


6e  =  —  -r-, — —  .  i   -r-    •  COS.  i  5  +  (  -7—    .  sm.  ^5  > 


[3B95C]  s^=     .^!!l^5(l£yeos.T,-f^).sin.rJ. 

f  (2455)  The  values  Se',  e'S'm',  depending  on  the  angle  Tr,,  noticing  only  terms  of 
the  third  order  in  e,  e',  7  [3891'"],  are  easily  deduced  from  those  of  ôe,  cSts  [3895,3895'], 
by  a  process  similar  to  that  employed  in  [3846« — gl  ;  using  also  the  same  abridged  symbols 
[.3895e]  Ts,  Tg,  Po,  Pq,  kc.  For  if  we  substitute,  in  [1288],  the  values  i'=  — 2,  i  =  —5, 
we  get  the  following  term  of  Se,  which  may  be  added  to  [38956],  to  obtain  a  symmetrical 
form  of  Se,   similar  to  [3S46i,  Sic], 

This  last  temi  may,  however,  be  neglected  in  computing  the  value  of   Se  ;  because  it  has 

not  the  small  divisor    5  71'  —  2n.      Now  changing  the  elements    m,  a,  n,  e,  &ic.    into 

[SSgSg-]    ^,^  ^^1^  ^^^/^  ^t^  ^ç,_^  ^j^j  jj^g  contrary,  as  in  [3846a,  d\,  we  find,  that  the  part  of  S  e',  arising 


VI.  ii.  §12.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  91 

To  obtain  the  values  of  5 y  and  Sn,  we  shall  observe,  that  the  latitude  of  m,     [3696"] 
above  the  primitive  orhit  of  m',    is     5= — y .  s'la.  (v  —  n),*     which  gives  [3897] 

as  =  —  5y  .  sin.  (v  —  n)  +  7  .  a  n  ,  cos.  (v  —  n),  [3898] 

Now  we  have,  in  [1342],t 

(     ('iPl.cos.(ôn't  —  2nt  +  52'—2s  —  v  +  n) 

7)i.a?i     )        \dy/  "^  '       ^ 

''•'-^^^ZJ^rS        ,.p,,       .         _      .  „  ^  [3899] 


dP' 

rf7 


sin.  (5  n't  —  2nt  +  ôs' —  2  s  —  v  +  n) 


[3895h] 


[38975] 


from  [3895i],  has  the  divisor    5n  —  2n',   which  is  large  ;  therefore  this  part  is  small    and 
may  be  neglected.      The  other  part,  derived  from  [3895/],  becomes 

„   ,  m.a'n'     i/dP\  ^     ,    fdP\      .     ^  ■) 

5n—Zn    i\de  /  \de'/  ^^ 

whlcli  is  easily  reduced  to  the  form  [3896'].      In  the  same  manner,  we  may  derive   S  ■a' 

[3896]  from  Sz,  [3895c].  ^^^^^'1 

*  (2456)     It  may   not  be   amiss   to   remark,    that   the  object   of   the   calculation   in 

[3896"— 3902],   is  to  ascertain  the  parts  of  ôy,   7  5  n    [3900,  3901],  arising  from  the     [3897a] 

perturbation  of  m   in  latitude,  by  the  action  of  m'  ;   supposing  the  fixed  ■plane  io  le  the 

primitive  orbit  of    m!    [3897];  these  parts   are  denoted  by   5^/,    y5„n,   respectively, 

in  [3899'].      In  like  manner,  the  action  of  m   upon  m'   affects  the  values  of    ôy,   y  Su 

by  terms  which  are  represented  by   «,  7,   7  5^  n,   respectively,  [3904].      The  sum  of  these     l35J7c] 

two  paits  of  i5  7  gives  the  complete  value  of  5  7,   as  in  the  first  equation  [3905]  ;  and  the 

sum  of  the  two  parts  of  <5  n   gives  the  complete  value  of  S  n,   as  in  the  second  of  the 

equations  [.3905].      Having  made  these  preliminary  observations,  we  shall  now  remark,  that     L^*'-'''] 

the  expression  [3897]  is  similar  to  [679],  changing  v,  into  v,  tang.  9  into  7  [669",  3739]  ; 

and  à  into  n+180''  [669",  3746]  ;  observing,  that  as  n  [3746  or -3902]  is  the  longitude     [3897«] 

of  the  ascending  node  of  m'  upon  the  orbit  of  m,  we  shall  have    n  4-  180'',   for  that  of  the 

[3897/^1 
ascending  node  of  m   upon  the  orbit  of  m,  taken  for  the  fixed  plane  [3896"].      Hence 

[679]  becomes    5  =  7.sin.(i'  — n— 180'')=:— 7.sin.(j;  — n),     as  in  [.3897].     Supposing     [3897^-] 

now   7,  n  to  vaiy  ;  the  corresponding  variation  of  4-  will  be  as  in  [3898]. 

t  (24.57)    Using  the  values  [.3895«],  also  ^  =  2,    tang.ç);  =  7,   é;=n   [3902,  1.3-37']  ; 
also,  for  brevity 

Ts=^5n't  —  2nt-\-5s'—2e,  Ts  =  5n' i —  2n  t  +  A  —  2n;  [3899a] 

the  expressions  of  R   [13.37"],  and  «   or   us  [1342],  become 

Ii  =  m  k.y-.  COS.  T^,  ûs=—^~y~^^.y.sm.[Ts  —  v-{-n).  [38996] 


[3900] 


92  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

Comparing   this   expression  with    the  preceding    [3898],    we   shall   obtain, 
[3899']     for  the  parts  of  6y,  y  an,  depending  upon  the  action  of  m!  upon  m,  which 
ô„.       we  shall  represent  bj  s^^y,    7^,,^^ 

6,7==—   "';""   ■5fl^Vsin.(5n'^-2ftt+5£'-2s)  +  ('^Vcos.(5n7-2n<4-5s'-2c-) j; 
"'  5?i'— 2ra   i\dy  /  ^  '  \dy  J  ^  '  ^3 

[3901]       yS,  n=     -4^-5f^Vcos.(5«7-2w<+5s'-2.0-('^Vsin.(5?i'^-2u<+5a'-2;)?; 

'    "  5?l  —  271  i\dy  J  \<iy/  ) 

7'  n-     in  which  y  is  the  mutual  inclination  of  the  tivo  orbits  to  each  other,  and  n  the 
longitude  of  the  ascending  node  of  in'  upon  the  orbit  of  m  [37461.      These 

[3903]  ^    .  .       *^,  ,        f  .  ^        '  ,  ,         T 

g_        quantities  also  vary  by  the  action  oi  m  upon  m  ;    so  that  it  we  put  these 

[3904]      last  variations  equal    to    6^  y,    5^  n  ;     the  whole  variations    being    6y,    iu  ; 

we  shall  have* 

[3905]  5y  =  S,y  +ô^^y  ■  6  H  =  ^,  H  +  6„  H  ; 

m.a'n'  ms/a  m.a'n'  m\/a 

[3906]  ^,7='^, • '5,/ '/ = -TT^  •  «5,, /- ;  ^,^=^, • '5„n  =  -^-— .6  n. 

•■        J  '  m!.  a  n      '  m\/a  m.aii      "  m  \/a      " 

If  we  compare  this  value  oî  5  s  with  that  of  R,  we  shall  find,  that  &$  =  —-, — ^;r  •{  ~, —  ), 
[3899c]  5,1—2/1   \dyj' 

provided  we  increase  the  angle  5>i'/ — 2nt  by  the  quantity  90'' — v-\-'n.,  by  which 
[3899</]     means     cos.  Tg     will   change   into       cos.  (  Ts  +  90'^  —  v-\-Jl)  =  —  sin.  (  Tg  —  v  -\-n); 

and  if  we  use  R  [3842a'],  the  expression  of  8s  [3899c],  becomes  as  in  [3899/,^,  or  3399]. 
[3899c]      Now  if  we  put,  for  brevity,     v  —  n  =  v, ,     and  develop  the  terms  of  [3899^],  by  means 

of  [22,  24]  Int.,  it  becomes,  as  in  [3899A], 

[3899/]    5s=g-^^^.»/.^Q.sin.(T,+90^-r  +  n)  +  (^).cos.(r5  +  90"-.  +  n)^ 

^'""'^^    =5-£k--'K^)-'^°^-(^^-^')-(i^)-^*"-^^'-^')^ 

^--^       -^B-n  ■  {  [(?).sln.T.+Q.cos.Tj.si„.,+  [Q.cos.T,-(^).sin.T.].cos.^. 

Comparing  this  with  5«^ — (5y.  sin.D,-)-7i5n.cos.  t),  [3898],  and  putting  the  coefficients 
of  sin.  v^,  cos.  V, ,  separately  equal  to  each  other  in  both  expressions,  we  get  [3900,  3901]. 
If  we  compare  the  value  of  7<5„n    [3901]   with  that  of  R   [3842a'],  we  easily  perceive 

[3899A;]     that  it  may  be  put  under  the  form    7(S,,n  =  —  an  .fdt  .i-—\;     and  having  found  7(5„n 


[3899/]      by  this  formula,  we  get  from  it  the  value  of  S^y,  by  changing  the  angle    T^  into    T^-\-9(y^, 
as  is  evident  by  comparing  the  two  expressions  [3901,  3900]. 

*  (24.58)    From  the  expression  of   7i5„n  [3899A:],  we  may  obtain  the  value  of  y  <î;  n, 
[3906a]    corresponding  to  the  action  of  m   upon    m'  ;  by  observing  that  the  values  of  P,  P' ,   which 


VI.  ii.  ^^  12.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  93 


This    beins;    premised,    if  we    substitute    these    different    quantities    in    the    c,,,mi'ityof 

■-  tlie  mean 

function   [3893],  Ave  shall  find  that  it  vanishes.*      Therefore  the  variations  ^,''11^1' 
of  the  excentricities,  of  the  perihelia,  of  the  nodes  and  of  the  inclinations  of     [3906'] 

the  orbits,  corresponding  to  the  two  great  inequalities  of  Jupiter  and  Saturn,  téms  here 

do  not  introduce  into  the  mean  motion  of  Jupiter,  or  into  the  greater  axis  of  its  l^^^^fj 

vanishes. 

occur  in  R  [3842(}'],  are  the  same  in  both  cases,  as  is  remarked  in  [3832  or  3846/',  &c.]  ; 
so  that  it  is  only  necessary  to  cliange  R  [3831]   into     —-R,     and     an     into     a'nf,     to 

obtain  from  [3899^-],  the  expression      yô^n  =  — —,.  a' n'.fd  t  .U-—\.       Dividing  this      [390C6] 

by   7Ô„n  [3899t],  we  get  the  first  form  of   '5,n   [3906];  and  by  applying  the  principle     [3906c] 
of  derivation  [3899Z]  to  this  value  of   y^'^,    we  obtain  that  of   5/  [3906].      The  second 
forms  [3906]   are  derived  from   the  first,   by   putting     an=a-^,     a'n'=a-i     [3709']. 
Substituting  the  values  [3906]  in  [3905],  we  get 

m'.an-\~7n.a'n'    ,                          .            m'.anA-m.a'n'        . 
Sy=  T .5„y;  y^n= -f~- .yS,,n;  3906e 

in  which  we   must  substitute  for    5,,y,    7  5„  n,    their  values   [3900,  3901].      Therefore, 

to  obtain   the  complete  values  of    5y,    y  5n,    we   must  change  the   factor    m'.  a  n    into     [3906/"] 

m'.  an  -\-  m  .  a  n',    in  the  formulas  [3900,  3901]. 

*  (2459)  If  we  substitute  the  values  [3S94— 3901]  in  [3393],  we  shall  find,  that  the 
terms  of  this  expression  mutually  destroy  each  other.  In  proving  this,  we  shall  neglect 
the  factor  — 6  am'.ffn^dt^,  which  affects  all  the  terms;  and  shall  use  the  symbol 
Tj  [38906],  also,  for  brevity, 

5n^^  nn'-^n^  5n'-2n  ^3907»] 

m  .an  m.an  m  .an--\-m.a  n 

Then  the  expressions  [3895,  3895']  may  be  put  under  the  following  forms  [39076]  ;  the 
similar  values  [3896,  3896']  become  as  in  [3907c]  ;  and  if  we  change,  in  [3900,  3901], 
the  factor  m'.an  into  m'.  an -\-m  .  a'n',  in  order  to  obtain  the  complete  values  of 
Sy,   yon   [3906/],  they  will  become  as  in  [3907(/]  ; 

(^-£-)-^os.T,  +  (^).sln.T,=-M.Je;      (^)  .  cos.r,-(^^)  .sin.T,=./lf,.e..;     [3907.] 

{'£)-^os.T,  +  ('l^yn.T,^^M.,.Se',      (If  )  .  cos.T.-('iÇ).sin.r,=M,.e'.-.';      [3907, 

(^).cos.7,+  (^).sin.T,  =  _J>/3.57;      (^) .  cos.r,-(^').sin.r,=./If3.7<Sn.     [3907d] 
VOL.  III.  24 


94 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


[3907] 


[3907^-] 

[3907A] 
[3907i] 


[3907fc] 

[S9071] 
[3907m] 

[3907n] 

[3907o] 
[3907p] 
[3907j] 


oi'bit,  considered  as  a  variable  ellipsis,  any  sensible  inequality,  depending  on 
the  square  of  the  disturbing  force  ;  and  it  is  evident,  that  the  same  result  holds 
good  in  the  mean  ^notion  of  Saturn  and  in  the  greater  axis  of  its  orbit. 


Substituting  tliese  values  in  the  first  members  of  the  following  equations  [3907e — ff],  then 
reducing,  by  the  neglect  of  the  terms  which  mutually  destroy  each  other  and  putting 
sin.^  7^5  -(-  cos.^  Tr,=  I,    we  get 

[3907f]     —Mi.5e.cos.T,—M,.e5v5.sm.T,=  (^^y,     M,.5e.sm.T,—M,.eô,z.cos.T,=  —(^); 

[3907/]     —M^.Se'.cos.T,—J\1^.e'&^'.s[n.T,=  (j£^  ;     M,.S e'.sm.T,—M^.e'&^.cos.T,=—(^^')  ; 

—J\l^.&'y.cos.T,—M;.y&n.s\n.T,=  (~^^  ;     M,.Sy .sm.T,—M,.ySu.cos.T,=  -('^)  ; 

Now  the  first  line  of  [3893]  becomes,  by  the  substitution  of  M^  .  e  f5  «  [3907//]  equal 
to     Se.  {Ml .  e  <5  w)  ^  Mi  .  e  5  e  .  (5  ra .       The   second    line    of   [3893]    becomes,    by   the 

substitution  of  [3894],  equal  to        e  5  ra  .  j  (-i~)  ■  cos.  T^  -f  (  —  )  •  sin.  T^  I  ,       and  by 

using  — ^j.^e  [3907i],  it  is  reduced  to  C(5«.( — Mi.&c)  = — Mi-eS  e.S-a  ;  adding 
this  to  the  first  line  [3907 /i],  the  sum  becomes  zero.  In  lilce  manner,  the  third  line  of  [3893], 
by  the  substitution  of  M.^  .  e'  5  ra'  [3907c],  is  equal  to  S  e'. (Jk/^  . e'Szs') ^M^.e'S e'.  d  -n'  ; 
and  the  fourth  line,  by  the  successive  substitutions  of  [3894']  and  — M^.Se'  [3907c], 
is  e'&z/.^ — Mg  .  5  e')  ^  —  31^.  e  S  e  .6zs' ;  the  sum  of  these  two  lines  is  therefore 
equal  to  zero.  Substituting  M^-yàlî  [3907<^]  in  the  fifth  line  of  [3893],  it  becomes 
S  y  .  {M3  .yôJl)Tz=  M3  .yôy.SH;  and  by  successively  using  the  equations  [3894"], 
also  the  value  of  — M^Sy  [3907rf],  we  shall  find,  that  the  sixth  line  of  [3893]  is 
ySu.( — ^3.157)=  —  M3.ySy.oll;  therefore  the  sum  of  the  fifth  and  sixth  lines 
is  equal  to  zero.  Hence  we  see  that  all  the  terms  of  [3893],  included  between  the  braces, 
mutually  destroy  each  other,  as  is  observed  in  [3906']  ;  consequently  the  values  of 
èe,  ÔZS,  5e',  Sz/,  5  y,  Su  [3895—3901],  do  not  produce  in  3a.ffndt.AR 
[3892  or  3715i]  any  term  of  the  order  of  the  square  of  the  disturbing  forces.  The 
function  3  a  .ffndt  .dR,  represents  the  mean  motion  of  the  planet  m  [1183];  therefore 
the  variation  of  the  mean  motion,  arising  from  these  values  of  i5  e,  S -a,   S  e',   &c.  is  nothing. 

Again,  from  [3709'],  we  have  2a  =  2n  '" ,  and  as  the  mean  motion  nt  or  n,  is 
not  affected  by  these  values  of  Se,  ^  ra,  Sic,  it  follows,  that  the  transverse  axis  of  the 
ellipsis  2  a  is  not  affected  by  the  variations  Se,  S -a,  &c.  now  under  consideration,  as  is 
observed  in  [3906"].  The  same  result  holds  good  when  we  notice  the  variations  of  the 
motions  of  the  body    m',   disturbed  by    m,    as  in  [3907]. 


VI.  il.  §13.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  95 

13.    TVe  shall  now  consider  the  variations  of  the  excentricities  and  of  the 
perihelia.      We    have    given,    in    [1287 — 1309],    the    expressions    of   the 

^         (1  C  (/  CT  d  c'  d  Ts'  , 

increments  ot       —-,       —,       —,      77"'         dependnig   on    the    two   great      [3i)08] 

inequalities  of  Jupiter  and  Saturn,  and  we  have  observed,  in  [1309",  &c.], 
that  the  variations  of    e,  ro,    e',    ra',    relative  to  the  angle      5  n' t  —  2>t^,t 


*  (-2460)  Tlie  expression  de  [1284],  is  integrated  in  [1286],  and  put  under  another 
form  in  [1283].  Now  as  this  last  expression  is  used  in  this  article,  we  shall  take  its 
differential  relatively  to  t,  and  then  change  the  angles  n't,  nt  into  ^',  ^,  respectively,  [39080! 
as  in  [1194'"]  ;  for  the  purpose  of  noticing  the  inequalities  of  the  mean  motion.  If  we 
put  fA=l,  i'^o,  i^2,  as  in  [.389.5rt],  we  shall  get  from  [1288]  the  following  value 
of    de;    and  in  like  manner,  from  [1297],  we  get  d-m  [.3908f/]  ; 

de=-m.andt.^    (^^).cos.(.5^'-2^+5s'-2s)_    (^^).sin.(5^'-2^+5s'-2a)^;     [390Sc] 
rf^=-,«'.««rf<.^^.(lÇ).sin.(5>'-2^+5s'-2£)+i.('^').cos.(.5f-2^+5s'_23)^.     [3908d] 

t  (2461)    If  we  put  the  values  of    §,  ^',    under  the  forms    ^=nt-}-N,    ^'^n't-{-JV',    [.3909o] 
we  shall  find,  by  comparison  with  [1304,  1305],  and  using  the  symbols  [3890a,  b], 

^=       (IÉS^-^^-^°^-^^-^'-^'"-ï^5l  ;  [39095] 

,,,  6m'.  a  n^      m^a     ,„  „ 

^  =  -W^;ji:2^^-^a'  ■  ^^---  ^^-^'-  ^■'"-  î'^l-  [39095'] 

Substituting  the  values  [3909«]  in  the  first  member  of  the  following  expression,  we  get 

5  ^'—  2  ^  +  5  £'—  2  E  =  5  «7—  2 M  <  +  5  e'—  2  £  +  (5  JV'—  2  JV) ^T^  +  (5iV'— 2iV),        [3909c] 

and  by  neglecting  the  square  and  higher  powers  of    5N'—2JV,    using  also  [60,61]  Int., 
we  obtain 

sin.  (5  ^—  2  ^  +  5  E-—  2  0  =  sin.  T,  +  (5 N'—  2  N) .  cos. T,  ; 

cos.  (5  ^'—  2  I  +  5  £'—  2  0  =  COS. T,  —  {bN'—  2  N)  .  sin.  T^.  ^^^^^'^^ 

Substituting  these  in  the  value  of  de  [3908c],  or,  as  it  may  be  called,   dàe,  we  get 

dhe=      m!.andt.\-(;^-£).cos.T,  +  (^-£).^n.T,\  [3909e] 

+  rr^.andt.{b  N'-  2  iV) .  ^  (^^-^)  .  cos.  T,  +  (—")  .  sin.  tJ  . 


96  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

may  introduce  in  these  expressions  some  variations  similar  to  those  produced 

The  part  of  this  expression,  depending  on  the  factor     5  JV' — 2  JV,     is  of  the  order    itJ^  ; 
and  as  the  other  terms  are  of  the  order     m',     we  must  notice,  in  them,  the  variations 

of      {- — 1,     (— — ),      arising    from    the    variations   of    Se,    (5  ra,    &tc.      The    additional 
[3909/] 

terms  of  the  vahies  of     f— — j,     {— — j,      from  this  source,  may  be  found  by  changing 

P,   P'     into      [  - —  ) ,     (  -T—  ) ,      respectively,  in  [3393c,  rf]  ;  and  as  the  former  quantity 

is  multiplied  by     — m'.and  t  .cos-T^,     in  [3909e],  and  the  latter  by     m'.  andt  .sin.T^, 
the  complete  expression  of   doe  will  be 

d5e^=     rn'.andt  .<  —  (~T~)  •  cos.  Ts  +  ( -;—  j .  sin.  Tg ^ 

+  m'.  andt.{5  JY'—  2JV)A  (^^  .  cos.  T5  +  (^)  ■  sin.  tJ 

(  +  ('^).Se  +  (^).S.+  (:^).Se' 
\'\de^   J  \dedTSj  '    \dedc'J 

[3909;»]  —  m'.andt.  cos.  Ts .  < 

\.^\ded^'J  ^\dedy)       '^\dednj 

\~\de^J  ^\ded-a)  '\dede'J  f 

-)-  m'.  audi .  sin.  Î5  . <^  >  • 

\'\ded-!a'J  ^\dedyj       '^~\deduj  ) 

Now  if  we  take  the  partial  differentials  of  [3894—3894"],  relatively  to  e,  we  get 

/ddP\     (dP'\,      f''''P!\         (i±^'\  —  _('!JL\_,  fill-'] 

\d7d^)  =  \d7)'^''-\   de-i  J'  \ded^)—        \de  J  -Kdc^) 

^^^^■3         {d^)='\-d^)'  \:d7d^j=-'\iûd7)' 

\d7dn)~~'^''\dedy)''  \dedn  )  '''\dedy)' 


Substituting  these  in  [3909/t],  and  retaining  only  the  terms  of  the  order   m!^  ;   or  in  other 
words,    neglecting   those    terms    of   the   first   line    of    [3909A],    which   are    independent 


VI.  ii.  §  13.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  97 

by  the  two  great  inequalities.      If  we  apply  this  method  to  the  elements  of 

of  the  factor     5  A'' — 2  JV    and  the  second  differentials     ddP,    ddP',     we  get 

dÔ6=     m'. a ndt.  (5 JV'— 2 A") .  |  (^\  .  cos.  T,  +  Cj^)  ■  sin-  T,  I 

ddP\  /dP'\  ,   fddP'\  fddP\,, 

,  /ddP'\    ,,   ,,   /ddP\     ,      ,    /ddP'\ 

(ddp\  fddP\  ^  ,- 


— ?«'.  a  lid  t.  COS.  T^. 


.   de^    J  \   de 

-\-m' .  and  t  .sin. T^ 


ddP'\     ,  /  dP 

oe  — 


[.3909fr] 


/ddP\     ,,,,/'ddP'\     ,  /ddP\        ,^ 

[-d7d7)-'^^+[-dId^)-^^^-[d7di)-^^^ 


We  must  substitute  in  this  the  vahies  [3895 — 3896',  3906/],  and  tlien  by  integration,  we 
shall  obtain  6  e  [3910],  as  will  appear  by  the  following  calculations,  using  the  abridged  symbols 

to  denote  the  factors  of  the  three  difterent  groups  of  terms  which  occur  in  [3910].  If  ^ve 
compare  these  expressions  with  those  in  [3907a],  we  shall  obtain  the  following  values  of 
m'.an,  which  will  be  used  hereafter  ;  these  equations  are  easily  proved  to  be  identical,  by  the 
substitution  of  [3907a, 3909/]  and  reducing.       m'.an=:MiK:,=zJ\'LJV2—M^.{J^^  +  J^:,).     [3909ml 

First.    We  have,  by  means  of  [3909&,  U], 

m'.andt .{i)N'—2JV)=:^—  —-:-—— . ^ — ~^,  ,        ' .{P.  cos.  Tr,—  P'. sm.T^l.d t 

[3909rt] 
=  — 2  A*!  .f  P.  cos.  T^  —  P'.  sin.  Ti\.dt. 

Multiplying  this  by     (-v— )  •  cos.  Tj  -f  f— — j  .sin.Tj,     we  obtain  the  value  of  the  first  line 

of  [3909Â-],  as  in  the  first  member  of  the  following  expression,  which,  by  means  of 
[1,  6,  31]  Int.,  is  reduced  to  the  form  [3909o]  ; 

-<iN,.dt.\P.cos.T,-P.  sin.Ts^.J  (^)  .cos.Ts  +  ^^Vsin.Ts^ 

>  •  [3909ol 

Its  integral  gives  the  terms  of  i5e   [3910],  depending  on  the  factor     (5mv/a  +  3m'v/«')- 
VOL.  III.  25 


98  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[3909]     the  orbits  of  Jupiter  and  Saturn,  and  put    àe,  «î  ts,   for  the  variations  arising 

Second.    The  term  of  [3909A"],  connected  with  the  factor     ( — ~j  .  dt,      is  as  in  the 

first  member  of  [3909p]  ;  wliich,  by  the  successive  substitutions  of  [3909»!,  3907e], 
becomes  as  in  [39095],  whose  integral  gives  the  corresponding  term  in  the  fourth  hne 
of  S e   [3910]  ; 

[3909p]     m'.an  . I— Se .cos.T^—eûzi .sm.Ts]  =  MijX^.  {  —  Ô  e  .COS.  T^—  e Ù 7Ô  .  sm.T^l 

[3909g]  =JV,J—Mi.Se.cos.7\—J\I^.e5z:.s\n.T,l=Mj'^\. 

ITiird.    The  term  of  [3909A:],  connected  with     [-j-tt  )-dt,      is  as  in  [3909r],  and 

by  reduction,  using  [3909m,  3907e],  it  becomes  as  in  [3909s]  ;  whose  integral  gives  the 
corresponding  term  of  the  fourth  line  of  [3910]  ; 

[3909r]     ni'.an.{Se.sin.T^ — eS-a.cos.T5l=^M^J\'^.\5e  .s'm.  T^  —  e^^.cos.Tgl 

[3909«]  =zJV2.{Mi.ôe.sm.T5—M^.eôzs.cos.Ts\  =  —M.{^\ 

Fourth.    We  may  proceed  in  the  same  manner  with  tlie  terms  of  [3909Ar] .  connected 

with  the  factors       (   .    ,  ,  ]  .dt,       { - — — r  r";      which  will   be    found   to   be  represented, 
\dede /  \dede  /  ^ 

|3909«1     respectively,   by  the  first   members   of  [3909/j,  r],    accenting  the   symbols     e,    8e,    S-!^. 

If  we  also  put     7n'.  anz^MjJV^  [3909m],  and  reduce  the  formulas  as  in  [3909c,  «]  by 

[3909m]    using  the  expressions  [3907/],  they  will  become,  respectively,    JV^.i  —  ],  ~"^3-(^j- 

Multiplying  these  by  the  factors  [3909;:],  and  integrating  relatively  to   t,    they  become  as  in 

the  last  line  of  the  expression  [3910]. 

/ddP\     , 
Fifth.    In  like  manner,  the  terms  of  [3909t],  connected  with  the  factors        ,     ,     ).dt, 
[m9v]  ,  \dedyj 

( -—].dt,     will  be  represented  by  the  first  members  of  [3909p,  j-],  changing   e,  êe,  ôzs, 

XdedyJ 

into    7,  (5  7,  5n,   respectively.      Then  substituting    in',  an  =  M^.  {Nç,-{- JV^)    [3909m], 

and  reducing  the  formulas,    as  in  [3909(7,  *]>  using   [3907^-],  they  become  respectively, 

[.3909«>]    (A'a  +  Ns) .  (^) ,      —  (JVo  +  A',)  .  (''^^ .      Multiplying  these  by  the  factors  [3909y], 

and  integrating  relatively  to  t,  we  get  the  corresponding  terms  of  oe  [3910]  ;  the  terms 
depending  on   JVo   being  in  the  fourth  line,  and  those  on    JV^   in  the  last  line  of  [3910]. 

Sixth.  The  two  remaining  terms  of  [3909A:]  are  as  in  the  first  member  of  [3909x]  ; 
which  is  reduced  to  the  form  in  the  second  member,  by  the  substitution  of  m'.  an^ M^  JV^ 
[3909m],   and    M^.Su    [39076].      Reducing  the  products  by  means  of  [31,  32]   Int., 


VI.ii.§13.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.  99 

from  the  square  of  the  disturbing  force,  we  shall  find 

[       \de)  \de 


{5n'—2nf  mV«'  \  2.(5ji'— 2n 

^      \  de  J  '\de 


Inequality 

of  the  ex- 

centricitv 

dP'\        ^  /dP\y  \      ofJupitei. 


2.(5)i'— 2îi) 


.  C0S.2 .  (5  n't—2nt-\-5;'—'2s) 


rfF\    f<idP\    JdP\  {ddP'\   .  /dP'\  fi^\f'[f\   fddP'\y     • 
I^J-yde"-  )       \de)\dei  J'^Kdy  j\dedyj      \dYj\ded  y )ç^ 


[3910] 


WiP\~_fdP'Yl 

m'g.aans  )    ,  iMlZ_AfiZ_l.cos.2.(5n'«-2n<.+5E'_2  5) 
"5n'— 27i*\  '^       4.(5n'— 2n).e 


-    lliZ_AlijL.sin.2.(5ji'f— 2n<+5e'— 2j) 
2.(5n'— 2îi).e 

,m'.aa'.nn'.t  WdP'\    /ddP\/dP\    /ddP'\       /dP'\   /ddP\       /dP\    /ddP'\] 
5n'—^n     'i\d^  )\dede'  )      \de')'\dede')'~\  dj  )\dedy)      \dy)'\dedy)\ 


.* 

5 


[3909x] 


it  becomes  as  in  [3909(/]  ;  then  integrating  relatively  to  t,   it  produces  the  terms  depending 
on    COS.  2  T,    sin.  2  T,    in  the  fifth  or  sixth  lines  of  [3910]  ; 

m'.andtA — \~T~)  •5'"-  ^s — \~r~)  '^°^'  "^ A  '  ^'^ 

-    •^.^'.l-©.s-.n.n-('^),cos.r,|. J(^^).».n-(-).sin.r.| 

*  (2462)    If  we  compare  the  expressions  of  de,   dis  [3908c,  r/],  we  shall  find,  that 
dvi   may  be  derived  from    de,   by  subtracting  90"^  from  the  angle     5^'— 2  ^  +  5  e'— 2e,     [3910a] 
and  connectbg  the  factor   -    with  each  of  the  quantities     (-7- ))    (-7—)  5    '^y  th's  means     [39104] 
the  angle    Ts  is  also  changed  mto    T5  —  90'',   in  all  the  terms  of  [3909e,  h,  A;],  in  which 


100  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 


a  e 


[3911] 


Inequality                 3m'2.aan3    (5mv/a+2mVa')    j     i    '-       Vrfe  /  \d<"/>      .     „  ,£.  „     o   ^ic-    o< 

perigee  of  (5n — 2ref.e  jnVa'  \  2.(5n' 2 ni 

Jupiter.  1  ^  ' 

+  i ^ 1 ^^ i-^.co3.2.  5;i'<— 2n(+5;'-2s) 

2.(5re'— 2ji) 

dP\  /ddP\       /'dP'\   /ddP'\       /dP-\  f'l±^\,/<l£\  f'^'^^'M 
d7)\de^  )'^\de  )\de^  J^Uyj\dedj)'^\d^)\did:^)y^ 

M'^.a^n^    j+^V^^"^^^   >..in.2(5„'/-2n<  +  5.c'-2.) 
^(5?i'— 2ra).e  '  "j  2 .  (5  ?i'  —  2  n) .  e 

+     \£L-L-h£— L.  COS.  2.  [5  n't  — in  t-j- 5  s'— 2  s) 
(5ra' — 2 re),  e 


I?!  m 

"(5 


re'.gg'nn'.<  5/'ijP\   fddP\       /dP'\    /ddP'\       /dP\    /ddP\       /dP'\    /ddP'\ 
n'—2n).e'l\d7)\dede')'\de')\dede')'^\(r^)\dedy)'\dy)\dedyl 


[3910c]  T5  explicitly  occms  ;  observing  that  no  change  must  be  made  m  the  factor  5  JV' — 2N. 
Hence  it  appears,  that  if  we  change  in  [.3909A]  the  angle  T5  into  T5  —  90"^,  without 
ahering    5  JV' —  2  JV,    and  then  muhiply  tlie  resuUing  expression  by    -  ,     we  shall  obtain 

[3910rf]    all  the  terms  of    d  Szi,    except  those  arising  from  the  variation  of  the  factor   -  ,  connected 

with  the  quantities     (— — J,     (—. —  )    [39106].       These  last    quantities   depend   upon    the 
two  following  terms  of    dôzs,    namely, 
[3910e]  ,«'.  an  dt.ll -("£).  sin.  T.-  ('i^')  .  cos.  T,  ]  , 

corresponding  to  the  two  first  terms  of  [.3909e]  ;  and  as  the  variation  of    -   is 

13910/]  _^_f^_l_.^(l^).sin.T,+  (^).cos.r,}       [39076]; 

also    m'.an=M^JVn  [3909m],  this  part  of    dozs   will  be  represented  by 

JVo      ,        (         /dP\        .      „  /dP"' 


[3910g] 


VI.  ii.  §13.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         101 

The  parts  of  these  expressions,  proportional  to  the  time   t,    give  the  secular 
variations    of    the    exceutricity   and    of    the    perihelion,    depending    on    the 
square  of  the  disturbine;  forces.      To  obtain  the  periodical  terms  of  v  depending      [3912] 
on  this  sqxiare,   we  shall  consider  the  term     2e.sin.  (n^  +  s  —  -in)     [3748],      [3012'] 
in  the  elliptical  expression  of  the  true  longitude.      If  we  put   6  e,  (5  ra,    for 
the  variations  of    e,    ■^,    depending  upon  the  angle     bn't  —  ^.nt-^-bi' — 2;, 


Tills  is  to  be  connected  with  the  terms  mentioned  In  [3910(ZJ,  to  obtain  the  complete  value 
of  do -a;  and  then  by  integration,  we  shall  get  5-ui  [.3911],  as  will  appear  by  the  following 
investigation,  taking  the  terms  in  the  same  order  as  in  the  preceding  note  [3909« — y]. 


[3910A] 


[3910î] 


In  the  first  place,   the  terms  depending  on     .5  A'"' —  2  JV,     are  multiplied  by  the  factor 
{— — j  .  cos.  Tj-j-f —— j  .  sin.Tg,      in  the  expression   of    d5e    [3909A],    which    becomes 

-.(— — J.sln.Ts .  (  — —  j  .C0S.T5,    in   dô-a  [3910f/].     Now  it  is  evident,  by  inspection, 

that  this  last  expression  may  be  derived  from  the  first,  by  changing      (  — --  1    into   - .  (  —  ) , 

/dP'\     .               1    /dP\  «     \    e/      [39ioi] 

and     (-7-]     iiito .( — j,     without  varying  the  angle  T5,  or  the  factor  5  JV'— SA"; 

therefore  v. e  may  use  the  same  process  of  derivation  in  obtaining  the  part  of  dozs,  depending  on 
oN' — 2.¥,  from  the  similar  part  of  due  [3909A:]  ;  or  in  other  words,  the  part  of  us  [3911], 
connected  with  the  factor    bm,y'a-\-'im  s/a',    from  the  similar  part  of  &e,  [3910]. 

We  shall  now  apply  the   principle   of  derivation  mentioned   in  [3910f/],    to  the  terms 

[3909p — «■],  and  we  shall  find,  that  the  factor  of     -.{— — ].dt,      in     do-,,     deduced 

e     Kde'i  J  '  [3910mJ 

from  [3909^],  is  N^.\—M,.5e.ûn.  Ts-f-  itfj .  e  5  «  .  cos.  Ts  |  =  A', .  (^\  [3907e] , 
producing  the  term     —  •  ("3~)  •  (-7~r)  • ''^-     '"    dàzi,    whose  integral  is  as  in  the  first     [3910ml 

term   of  the    fourth   line    of     5  a    [3911].       The  term    [3909s],    by  similar   reductions, 

A%    /dP'\     /ddP'\ 
gives     —  •  (  7^]  •  (  "TT"  )  •  ^  '     ^'^^  *^™^  [3909^]  give  [3910n] 

A3    /rfPN    (ddP_^  A-3    (dJF\    (ddP'\  [3910,] 

e    \dt)-\dtde')-''  e    \de' J  '  [dede' J  '  ^  ' 

the  terms  [3909ic]  give 

as  in  the  fourth  and  seventh  lines  of  5  a  [3911]. 
VOL.  III.  26 


102  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

and  upon  the  first  power  of  the  disturbing  force,*  also  6'  e,  6'  w,  for  the 
[3913]  preceding  variations  of  e,  w,  depending  upon  the  double  of  this  angle  ;  f 
[3913']      moreover,  if  we  denote  by     à  s    the  sum  of  the  two  inequalities  of   m,    the 


Lastly,  the  terms  of   dSzi,    deduced  from  those  of  doc,   in  the  first  member  of  [3909r], 
by  the  principle  of  derivation   [3910f7],  are 

[3910p]  m'.ajirf<.|  — -.(^— j.sin.T5+-.(^— J.C0S.T5J  .Sis; 

which,  by  the  substitution  of    7n'.a7i  =  M^JV„    [3909m],  and  5  a  [3907i],  becomes 


[39105] 


Adding  these  terms  to  those  in   [3910o-],   and  putting      cos.^  Tj  —  sin.- T3  =  cos.  2  Ts, 
2  sin.  Tj  .  COS.  Tg  =  sin.  2  T^ ,     we  get 

and  by  integration,   it  produces  the  terms  of    i5  -si,    depending  on     sin.  2  T5 ,     cos.  2  Tj , 
in  the  fifth  and  sixth  lines  of  [3911]. 

[3912a]  *  (2463)    These  values  of    5  c,    5^,    are  given  by  the  formulas  [3907i]. 

t  (2464)    The  formulas  [3910—3912']  give,  by  using  T5  [38906], 

3m'2.a3n3      (5»n/a-t-amVa')     A        L       V  f<e  /  \dej_i 

3.(5n'— 2n)3"  my  a'  '\       r^,/dP'\        ^/dP\ 


[3913a] 


[39136] 


3m'3.  f)3»,3      (^m^a-\-^mVa')     1        L       \de/  \dt/A 


VLii.§13.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         103 

one    depending  on    the    angle      5n't  —  '2.nt-{-Bi  —  2s,      the   other  upon 

the  double  of  this  angle,*  the  term    2e  .  sin.  (nt^s  —  ^),    will  become  [3913"] 

(2  e  +  2  5  e  +  2  <5'  e)  .  sin.  («  ^  +  =  -f-  d  s  —  ^  —  5  =i  —  5'  ^) .  [39i4i 

If  we  neglect  the  cube  of  the  disturbing  force,  the  preceding  expression  may      [3i)U'| 
be  developed  in  the  following  form,t 

2  e  .  sin.  (nt-\-s~\-  6  s  —  ra) 
+  2  (5  e  .  sin.  (n  t  4-  s  —  ra)  —  2e6is  .  cos.  (nt  -\-s  —  ra) 

^  [3915] 

+  \2ô'  e  +  265^  .5s  —  e.  Ç6v>)-\.  sin.  (n  t  +  s  —  w) 
—  [2ed'îJ  +  2oe.da  —  26s  .ôe}.  cos.  (nt  +  s  —  zi). 

The  term     2  e  .  s'm.  (nt  -\-  s  -{- 5;  —  i^)     is  that  obtained  by  increasing  the      [3915] 


*  (2465)    The  great  inequalities  [1197,  1213,  Sic.],  are  to  be  applied  to  the  mean 
motion  of  the  planet  [1070"].      If  we  notice  only  the  chief  terms  of  â  s,   having  the  divisor     [3914a] 
(5?i'— 2n)^    they  will  become,  by  putting    i^^5    in  [3817],  and  using    Tj  [3S90è]  ; 

^  '  =  (sl'-atp  •  ^  ^-  ^"'-  ^=  -  ^'-  ''"•  ^=  '  •  P^^^''^ 

We  may  remark,  tliat  the  terms  of  v  [3748],  depending  on   e^,  e^,  &c.,  are  here  neglected     [3914c] 
by  the  author,  on  account  of  their  smallness  ;  they  are,  however,  noticed  by  him  in  the 
fourth  volume  [9062,  &c.]. 

I  (2466)     Putting     a  =  nt  +  i-[-5s  —  TS,     b^ô-^^ôt^',     in  [22]    Int.,    we   get     [3915a] 
the  second   member   of  [3915&],   which  is   successively  reduced   to   the   form    [3915c], 
by   usmg    [43,  44]    Int.,    neglecting    terms    of    the    order      m'^,      and    finally    putting     [3915a'] 
cos.  o  =  cos.  [nt-\-  S' —  to)  —  us.  sin.  (w  t -}- s  —  ra)    in  the  term  multiplied  by  5  w  ; 

sin.(n<-|-£-|-5£— ^— 5i3— ô'î3)  =  sin.«.cos.((533-{-5'xn)  — cos.  a.sin.(r5x3-|-i5'-5j)  [39156] 

=  {1 — i .  (Sts)^]  .sin.w —  (6z!-\-S'zi)  .cos.  a 
=sin.a  — J.((Jûj)~.sin.(7i^-f"^~^)~("''+'^'®)  •cos.(w^-|-£— ro) 

-\-  o-us. 5 1. sin.  {7it-\-s — ra). 

Multiplying   this   by     2e4-2i5e-r2i5'e,      and  neglecting  terms  of  the    order    m' ^,    it 
becomes  as  in  [3915]  ;  observing,  that  in  the  term  multiplied  by    2  i5  e,    we  may  put 

sin.  a  =  sin.  (n  <  -}"  ^  —  w)  +  i5  s .  cos.  (lit  -\-  i  —  w).  [3915rf] 


104  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[3915  "]     mean  motion    n  t,    by   &  j,    in  the  elliptical  part,  according  to  the  directions 
in  [1070"].      The  two  terms 

[3916]  2ie  .  sin.  (nt  -\-s  —  n)  —  2  e  (î ^  .  cos.  {nt-\-s  —  cr) , 

form  the  inequality  depending  on  the  angle     Qnt  —  Sn't^Ss  —  5e',     given 
by  the   formula  [3718].*       If  we  then  substitute   in  the  other  terms,  the 


*  (2467)    If  we  put    ?'  =  5    in  [3814,3825],  where  only  the  terms  having  the  divisor 
5  ft'— 2  m    are  retained   [3818',  3824],  we  get 

[391Go]     '-^==i/.cos.(5n'i— 3n«  +  5£'— 3s  +  .^);       (5j;  =  2H.sin.(5n'i— 3««  +  5e'— 3e+^)  ; 

and  we  may  observe,  that  this  value  of    ^  v   is  easily  obtained  from  that  of    r(ir,    by  means 

[3916!>1     of  the  formula   [3718];  retaining  only  its  first  term     5v=^     ^  ,      which  contains  the 

small  divisor  5  n' — 2;i  [3814,  &ic.].  If  we  substitute,  in  this  last  expression  of  (5  v,  the 
value  of    r  (5  r    [3876f/],  neglecting  the  small  terms  depending  on  X,  it  becomes 

[3916e]  (St)  =  2  ue.  sin.  (n  C +  s  — w)  —  2  e  (5«  .  cos.  [nt -\-s---ui). 

Comparing  these  two  values  of  5d  [3916a,  c],  we  find,  that  the  two  terms  in  the  second 
fine  of  [3915],  depend  on  the  angle  bn't — Qnt-\-bi' — 3e,  or  ^nt — bn't-\-'è3  —  5s', 
as  in  [3916'].  The  same  result  may  be  obtained  by  the  substitution  of  the  values 
of  <3  e,  c  5  w  [39076]  in  [3916],  and  using  the  symbols  Tg  ==  5  w'ï!  —  2  «  <  +  5  s'— 2  e, 
W=nt  -\-s  —  Î3  ;  since  it  becomes,  by  successive  reductions,  as  in  [3916^];  being 
of  the  form  mentioned  in  [3916']  ; 

25e  .sin.?^— 2e5«.cos.?f  =— ^  'KS)  '  ''°''  ^^  "^  (Ï)  '  "'""  ^'  \  '  ™'  ^ 
[3916e]  ' 

=  —  ^  ■  (^)  •  Icos.  Ts  .  cos.  TV-\-  sin.  T, .  sin.  W\ 
Ml     \de/     ' 
[3916V] 

-I-  J- .  (^\  .  |sin.  Ts'.  COS.  fV—  cos.Ts .  sin.  ?F} 
[3016/1  =--.  {-)  •  COS.  in  -  TV)+^.  f^')  .  sin.  (T.-W) 

=—■—.  (--]  .cos.  (5  7i'  t  —  3  n  t  4-  5  t'—3  s  +  zs) 

[3016g]  2 

+  — .  f  — ]  .sin.  (5n'<  — 3?ii-f-5s'— 3e  +  -5î). 


VI.  ii.  «^^  13.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        105 

values   of    he,    ôt^    [39076],    and    for     ô' e,    b' -.,     their    preceding    values 
[391 3f/,  6]  ;  the  sum  will  give,  by  neglecting  terms  depending  on  the  sine 
and    cosine    of     «ï  +  5,      because    they    are    comprised    in     the    equation      [3917] 
of  the  centre," 

(on— 2»)3'  mVa'  f        \(/e/  \de/S 

_  3m-s.«^r.3    [5mM±ivW^)   ^j,,(dJ-\_^_  f^V..sin.  (5.  ^-10,/^  +  5.-10.-'-^).      [3918'] 
{5n'— 2n)3  m'y/»'  C        \de  J  \dejS  ^ 


ir  we  put,  in  [3916-],      (^)  =  — 7»/jIJ.sin.(^  — ^),      (^-£^  =  M,H.co5.{A  —  ^),     [3916A] 

and  reduce  the  result  by  means  of  [21]  Int.,  it  becomes  equal  to 

2  H.  sin.  (5  Ji7  —  3  n  t  +  b^  —  3^+Jl).  [3916il 

This  is  of  the  same  form  as  [382.5],  which  represents  the  most  important  term  of  this  form 

and  order,  having  the  small  divisor    5?i'— 2  k    [3824].      The  factor  ZJ' is  of  the  second     .gg^g-,! 

fdP\      fdP'\ 
dimension  in   c,  e'  [3314i],  being  of  the  same  order  as  the  quantities       (77)'    ITT")' 

For  the  values  of    P,  P    [12S7],  which  correspond  to  the  angle     T5,    are  of  the  third 
dimension   in    e,    e',    &,c.    [957'"',  &c.],    and   their    differential    coefficients,    which    occur     [3916t] 
in  [391fiir],  are  of  a  lower  order  by  one  degree. 

*  (2468)     The   first  and  second  lines  of  the  expression   [3915]   are  accounted   for  in 
[3915",  3916]  ;  the  remaining  terms  become,  by  using  the  abridged  symbols  W,  T^  [3916rf], 

\2à'e-{-2e5cz.6s~e.{S^f\.sm.Tr-\-\  —  2c.o'is  —  2Se.ii^-{-2ôe.Se\.cosJV;  [3917a] 

in   which   we   must  substitute   the   values   of    Se,    5 -a    [39076],    (V  e,    5' ■a    [3913a,  b], 

Si  [39146].      In  making  these  substitutions,  the  terms     Szi.Ss,    [S-a)^,    Se.  5 -a,    Ss.Se, 

will    produce   factors    of   the    forms      ^.cos.^Tj,      ^'.  sin.^Tg,      »4".  sin.  Tj .  cos.  T, , 

or      à^  +  ^^.cos.2r5,      i.(]'—hA'.cos.2T^,      ^  ^  .  sin.  2  T.,      [1,6,31]     Int. 

Substituting  these  in  [3917«],  we  find  that  the  parts    ^  A,   ^Jl',    independent  of   2  T^ , 

produce   terms    depending  on     sin.  W,     cos.  W,      of  the    form      a  .  sin.  W -\-h  .sm.  (V ; 

which,  by  putting      a=k  .sir.,  p,     h^Tc .  cos.  p,     and  reducing  by  [21]  Int.,  becomes 

fc  .  sin.  (/f'-j- (3)  =  Ar.  sin.  (n  ^  +  ;  —  «  +  (3)-       This  maybe  connected  with  the  equation     [3917c'] 

of  the  centre  [3915'],  as  is  observed  in  [3917]  ;   therefore  these  terms  may  be  neglected, 

and  we  may  substitute  in  [3917«]  the  following  values, 

C0S.3  Tj  =  1  COS.  2  T5  ;     sin.^  T,=  — ic^.2T^;     sin.  T5 .  cos.  T,  =  |  sin.  2  1\ .  [3917d] 

Substituting  these  in  the  square  of  Svs,  multiplied  by   — e,  deduced  from  [39076,  a],  we  get 

VOL.  III.  27 


[39176] 


[3917c] 


106 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


This  inequality  may  be  put  under  the  form  [3921]  ;  for  if  we  represent  by 
[3919]  6v  =  K. sin.  (5  7i'  t  —  3  ni  +  5  s'  —  3  e  +  B), 


This  term  is  destroyed  by  the  corresponding  terms  of     2à'  e,     deduced  from   the  third 
hne  of  [3913a],  so  that  the  sum  becomes 


[3917/]     oye_e.Mn)2==— ,-- 


3  m''^.  a^n^     (5  m  \/a  -j-  2  m  V«') 


:^-©+^-©]---^' 


15»'— 2n)3 


m'^/af 


+ 


:''■■©-^•(^^)] 


.2T, 


Multiplying  the  value   of    e&zs    [3901  b,  a],   by    as    [3914a],    and  reducing   the  product 

by  means  of  the  expressions    [3917(7],    we    get,   by  putting   the    factor    6,    in    this   last 

1       1      /•  r.    2m'i/i' 

expression,  under  the  lorm      3  .     ,  ,  ,  , 

mya 


[39l7g] 


2eSzs,(is: 


3»i'2.a2n3     2mVa' 


(5n' — 2n)3'   my  a' 


[39177i]    Adding  this  to  [3917/],  and  putting,  for  brevity,        ^£,  =  - 


3m'3.aan3    (5mv/fl  +  4 m'y/a') 


(5n'-2n)3' 


711' y^a' 


we  get 
[39l7i]  25'e  +  2e5«.⣠ — e.(^î3)2= 


Again,  multiplying  together  the  two  equations  [39076],  and  dividing  by   ^M^^.e  [3907a], 
we  get,  by  substitutmg  the  values  [3917»^/], 


[3917fe] 


—  25c  J«  = 


m'a.a3  7i2 


de  J         \de 


(5n'— 2n)2.e      J  r/dP\     /dP' 

Adding  this  to  the  expression    à' tz    [3913?»],  multiplied  by    — 2e,    it  is  destroyed  by  the 
terra  depending  on  the  third  line  of  [3913i],  and  the  sum  becomes 


3m'2.a2n3  (5mv/a  +  2?nVa') 
\o»l.{l\  (5„' — 2n)3  m'\/a 


vJ+[m^)+-q: 


.cos.2Ts 


-[-m-^m-- 


VI.  ii.  §13.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        107 

the  inequality  of    m,     depending  on      3  7it  —  5n't-\-3i  —  5  s';*      and   as 
in  [3889], 

the  great  inequality  ^  =  H.  sin.  (5  n'i  —  2  «  ï  +  5  e'  —  2  s  +  Â),  [392oj 


Multiplying     —My.Se    [3907i]    by      —  jj^,     also  by    <5  e  [3914J],  and  then  reducing 
by  means  of  [3907a,  3917(/],  we  get 


+[--f^)+'--(^: 


.cos.Srs 

The  sum  of  [3917/,  m],  using  JI:/4  [3917A],  is 

5  — Seô'îs— 25e.5t3  +  2i56,5e}=<(  >.  [3917n] 

Multiplying  [3917i]  by  sin.  W^,  and  [39177i]  by  cos.  fF,  then  adding  the  products, 
we  find  that  the  first  member  is  equal  to  the  expression  [3917a]  ;  and  the  second 
member,  by  the  substitution  of  sin.  2  Ts .  sin.  W  -f  cos.  2  T5 .  cos.  ?F  =  cos.  (W—2T5), 
cos.  2  T, .  sin.  TV—  sin.  2  T5 .  cos.  fV=  sin.  (  W—  2  T5  ),    becomes  [39iro] 

and  by  resubstituting  the  values  of  M^ ,  T5 ,  ?F  [3917A,  3916J],  it  becomes  as 
in  [3918,3918']. 

*  (2469)    The  expression  [3919]  is  of  the  same  form  as  that  assumed  in   [3826],  or 
that  computed  in   [3916^],   assuming    1  =  5;    moreover    [3920]   is  the  same  as  [3889].     [3920o] 
Hence  if  we  put,  for  brevity,       T5  =  5  ?i'  <  —  2  71  <  +  5  e' —  2  s,       fV^  =  nt  -\-  s,      and    [3920o'] 
then  make  the  two  expressions  [3919,3916^]  equal  to  each  other;  also  [3920,  39096,  a], 
«sing   M  [3907a]  ;  we  shall  obtain  the  two  following  equations  ; 

K.ûn.{n-W,+B)=^^^^^.\-(^i^ycos.{T,-W,+^)+(^-^ysm^^^^  [392061 

H.sin.CTs-f-  1)  =(5  Jlyjja  •{P-c0s.r5-F.sb.T5}.  [3930c] 


108  PEUTUllEATiOiVS  OF  THE  PLANETS,  [Môc.  Cél. 

the  preceding  inequality  will  be,  by  ^69,  of  the  second  book,* 

[3921]         ^^_      (5>V«+4>»V«')^ff^-,3i^^.(5,,,_10^,,^5,_10,_^_^j, 

m\/a  ^  ' 

In  like   manner,    we   shall    find,  by  noticing   only  the    secular  variations,! 

*  (2470)     Multiplying    together  the  equations  [39206,  c],  and   reducing   the   products 
by  [17 — 20]  Int.,  we  find  that  the  first  member  becomes  equal  to 

[3931a]  I  ÛK .  COS.  {W^J^Â  —  B)  —  lTl  K.  COS.  (  fF»  —  2  T-.—  B  —  A)  ; 

and  the  product,  in  the  second  member,  depends  on  similar  angles  JV»,  W^ — 2T5. 
Now  as  these  expressions  must  be  equal  to  each  other,  whatever  be  the  value  of  t,  we 
may  put  the  terms  depending  on  the  angle  /Fg  —  2  T5  in  both  members,  separately  equal 
to  each  other,  and  v/e  shall  get 

_  _  6m'2.(i2n3     )        L       \de.  J  '         \de/_\ 

[.•39216]     —  è  HK.  cos.  { W..—'iTi,—B-A)  = — ,r„>_g„a  .  < 

^D7l  — ^raj-'     \       |-       //p/v  /,!P\-\ 

This  equation  being   identical,   we  may  change      W.,  —  2T5,     into     !-V„  —  2  T5 -{- OO"*  ; 

by  which  means,  the  expressions      cos.  (TF.  —  2  75 — B  —  7]),      sm.  {IV.2  —  2  T5  —  ûj), 

[3921c]     COS.  (H'.,  — 2T5— ®),  become,   respectively,  —ejn.  (FF3  — 2 '/'s  — iî— J), 

cos.  (  JV^  —  2  Ts  —  tn),       —  sin.  ( TFg  —  2  Tj  —  -)  5       substituting  these  in  [3921^-],  and 

multiplymg  the  result  by  '^,—^ ,      t'le  first  member  of  the  product  becomes  as 

in  the  second  member  of  [3921]  ;  and  the  second  member  of  this  product  includes  the  terms 
[392W]    [391S,  3918']  ;    observing,  that       fF.j  —  2  1\=:  but  —  10  «'  <  +  .5  ;  —  10  s'     [3920rt']  ; 
therefore  the  inequality  [3921]  is  equal  to  the  sum  of  the  two  expressions  [3918,  391S']. 

t    (2471)      Using    the    abridged  symbols      P„,     P^,     T,,,     Sic.     [38466— f7]  ;      also 
[3922a]     Z  =  b?J — 22,-\-b^ — 2s.     Z^=b2,  —  2^'  +  5£  — 2s';     we  find,  that  the  expression 
of    de    [3908c]    may  be   rendered    symmetrical    by  the    introduction    of  the    two    terms 
depending  on  the  angle    Z^ ,   or    T^ ,    in  the  value  of  R  [3S46c]  ;    so  that  we  may  put 

,       <.fdP\  „       fdP'\      .       _,     /dP^\  _         fdP'n\      .       „? 

[3Î326]       de  =  —m'.andt.j^[-jjycos.Z—i^-j-ysm.Z+^~ycos.Z,  —  l^^j^ysm.Z,^. 

In  computing    S  e    from  this  expression,  it  is  not  necessary  to  notice  the  angle    Zg ,   because 

[S922C]     it  does  not  produce  terms  which  are  so  essentially  increased  by  the  small  divisor     5n' — 2n, 

as  has  been  already  observed  in  [3846f/"].       From  this  expression  of    de.   we  may  derive 


VI.ii.§13.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE, 
depending  on  the  square  of  the  disturbing  force, 


ôe'=- 


3  irfi.  a3  n3.  t      (ôm\/a-\-2m'\/a') 
[5n  —  2n)-.a''  m\/a 


5)i' 


a'g  n'3  ■  t    ^/(/P'N  /ddP\       /dP\  fddj^ 
,i'—2n     'i\de'  )\ilc"i  J\d7)\d7^ 


dP 

77 
dP' 

dy 


+ 


mm'.aa'.nn'.t  (.^dP'\  /ddP\      A/j 
5n' — 2?^       l\de.  Jydedc'J      \d 


dP 

e 


ddP' 


dede'J      xdy 


ddP 
de'dj 

ddP_ 
de'dy 


dP\  /ddP'\ 
J^,}\de'dy) 


■dP\  /ddP' 
dy  J  \dt'dy^ 


109 


Secular 
inenuality 
of  ilie  ex- 
centricity 
of  Saturn. 


[3922] 


iliat  of  de,  by  changing  the  elements  of  tlie  body  m  into  those  of  ?«.',  and  tlie  contrary  ; 
by  which  means  P  changes  into  Pq  [3846(/,  &c.],  P'  into  P'o ,  Z  into  Zo,  «  into  «', 
e  into  c',    &:c.  ;    hence  we  have 


(/e':=:  —  m.a'n'  (lt.\  [ -r-ri  -cos.  Z, 


U'/e'/' 


,sIn.Zo  +  (^). 


cos 


Z  — 


rfP' 

77 


.sin.Z^ 


Neglecting  the  terms  of  this  expression  depending  on   the   angle  Z,,,    because  they  do 

not   produce   by  integration  the  small   divisor     bn'  —  2k;      then  substituting  the  values 

of  sin.  Z,  cos.Z  [.3909fZ,  .3922rt],  we  get  the  following  value  of  dc,  or  as  it  may  be 
written    d&e',    being  similar  to  [3909e], 

d  <i  c  ==      m  .a  n  d  t  .< —    — —    .  cos.  i  s  +    — r-r    •  sm.  1  r,  > 
I        \de  J  ^    '    \de'  J  '' ) 

+  m .  a'  n'  d  t .  {5  JV'—  2  A") .  ^  (''|^')  .  cos.  T,  +Çj^)  ■  si"-  T, I . 

The  part  of  this  expression  depending  on     5  JV' —  2  JV,     is  easil)-  deduced  from  that  in  the 

tirst  line  of  [3909fc],  or  from  its  development  in  [3909o]  ;  by  multiplymg  it  by     —, , 

and  changing  the  partial  differentials  of  P,  P',  relative  to  e,  into  those  relative  to  e. 
Hence  we  obtain  the  following  expression  of  the  part  of  d5e',  depending  on  the 
factor    (5JV'— 2JV)    [3922/], 


'■r^)---©+[''-©+-'-(S) 


-.,    m. an     , 

—  J\ , .  — .d  t. 


Now  by  successive  reductions,  using     an  =  a       [3709'],     an'=a'        we  get 


[3922d] 
[3922e] 

[39226'] 
[3922/] 

[3922^] 


[3922A] 


m.a  '  a 


hence  from  [3909/],  we  obtain 


m'.an 


VOL.  in. 


3  m'~.  «2  }i3     (.5  m  \/a  -\-  2  j^V"')      "^  •  " 


(on'— 2n)2 


28 


3mS.  a3?i3      (.5nn/a-f-2mVa') 
{5îi' — 2nf.a''  m^a 


[3922^1'] 


[3922i-] 


110  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cùl. 


of  the 
perigeo  of 
Saturn. 


[3922/] 
[3922?»] 


[3923c] 


{5n'—2nf.a'e''  m\/a  'X       \de'J~      '\de'J^ 

dP\  /ddP\      /dP'\  fddP'\      fdP\  fddP\      fdP'\  /ddP'\) 


nAa"-inKt     (,/dP\  /ddP\   ,  fdP'\  fddP'\   ,  fdP\  fddP\   , 


yr\dy  )\U'dyJS 


mm 
■(5^ 


.aa'.7in.t   WdP\   /ddP\       /dP'\  /ddP'^.       /dP\   /dJP\    ^  /dP"\  /  d  d  P' \)  ^. 
—2n).e''i\dej\dede')'\de  )\dede')^\dy )'\dedj)  '  \d^ )\d7I^) ^  ' 


Substituting  this  in  [3S22A],  and  integrating,  we  find,  that  the  terms  multiphed  by  i, 
become  as  in  tlie  first  line  of  [3922]  ;  the  otlier  part  depending  on  2  T5 ,  produce 
in   (5  e'   tlie  terms 


[39224]  ~2.(3n'-2n)W"  '^Wa  j        r-        /.^p^x  /,;p 


.  sin.  2  T, 


.  cos.  2  75 


If  we  compare  the  terms  of  d  rS  e,  whicli  are  independent  of  (5  .V —  2  7V)  [SOODe], 
with  those  of  dSe  [3922/*],  we  find,  that  the  latter  maybe  derived  from  the  former 
by  changing  the  elements  m,  a,  n,  e,  w,  &,c.  into  m',  a',  n',  c',  ■cr',  &ic.,  respectively, 
without  altering  P,  P',  T5  ;  and  as  the  divisor  5// — 2«  is  introduced  merely  by 
the  integration  of  terms  depending  on  the  sine  or  cosine  of  the  angle  T^  and  its  multiples, 
this  divisor  xvill  also  be  unchanged.  Now  making  these  changes  in  the  secular  terms,  in 
the  fourth  and  seventh  lines  of  5  e  [3910],  we  obtain  the  similar  terms  in  the  second  and 
third  lines  of  S  e  [3922]  ;  moreover  the  periodical  terms,  depending  on  2  T5  ,  in  the  fifth 
and  sixth  lines  of  oe   [3910],  produce  the  following  terms  of    oc', 

t3^22n]  u-E^;r^^,-  \  K77)  -[-17)  J-^°^-'^^^-^- W)  •  (77)  -^'"-^^^^  3  • 

[3922o]      The  sum  of  ihn  expressions  [3922Àr,  rî\   may  be  represented  by   o'e',    to  conform  to  the 
notation  in  [3913],  the  characteristic    &'   being  used  to  include  the   terms  depending  on 
[3922p]     the  angle    2T5.      These  terms  are  used  in  [3924c]. 

*  (2472)     In    the    same   manner  as  we    have   deduced   the    expressions    [3922'^,  e,/] 
from  [3903c],  we  may  obtain  the  following  expressions  of   d  -,,  d  3',  d  &  t^'  from  [3903(Z]  ; 

[3923«1        ^.=-.'.««^..51.(^).sm.Z+^.('^).cos.Z+J.(^).sin.Z,+  ^(^).cos.Z„>; 
[3923.]       d.'=-m.a'n'dt^^,.(^ysn.Z,+l('^^^^^ 


d5zi'=.     m.a'n'dt}—\.  f^")  .  sin.7',— -,.  f'-^Vcos.  T,  \ 
(       e     \de  /  e     \de'  J  ) 


+  m.aVrf^(5JV'-2A').^-i.(^).cos.T5  +  ^,.(^).sin.T,|. 


VI.  ii.  §  13.]    DEPEiXDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         ]  ]  I 


We    also    find,    that     the    motion    of      wi'     in    longitude,    is    affected    with 
the   inc(|na]itj* 


3iiAa3n3      (3  mv/a-|-2niVV) 


(an'— 2n)3.a'' 


m^a 


.cos.(4  nt—0  n't+i  5—!)  e'— tj') 


+ 


■     ,  /dP'\        „   /dP\l 


[3924] 


This  last  expression  being  developed,  as  in  [392r2o-,  &,c.],  and  integrated,  gives  this  part 
of  ^33'.  It  may  also  be  derived  from  die'  [39:2:2/],  in  the  following  manner.  We 
perceive,  by  inspection,  that  the  part  of  [3923c],  depending  on  the  factor  5  JY' —  2  JV, 
can    be    derived    from    the    corresponding    terms    of      doe      [3922/"],     by    changing 


same 


/dP\     .  1    /dP'\  ,      /dP'\     .  1     /dP\         ,^  ,       , 

(  —  1     into     -, .    -r-r    ,        and        -rr       mto î-\~r~,  )■       Ii  we  make  the 

\de'/  e'    Kde'J'  \de'J  e     \de' J 

changes  in  the  first  line  of    S  e'  [3922],  which  was  derived  from  the  factor     5  JV' —  2  JV, 

[3922 j,  &.C.],  we  get   the  first  line  of  the  expression  of  ù'bj'  [3923]  ;    and  the  periodical 

terms  of   e'tJ^',    corresponding  to  [3922A:],  become  equal  to  the  following  function,  which 

is  used  in   [3924n]  ; 


3m-.a?n^  {5m^a-{-^m'^a) 


rfc' 


2.(5»i'— 2)1)3.  a' 


m\/a 


-[-(f)--(S)] 


.  cos.  2  Ts 


1.  2  7; 


[;3933f/] 


[392:iÉ] 


[3923/1 


[3923g-] 


The  part  of  (/  0"  to'  [3923c],  which  is  independent  of  5  JV' —  2  N,  may  be  derived 
from  the  corresponding  part  of  (ZtSts  [3908f/,  3910a — e,  or  3911  J,  by  the  principle 
of  derivation  mentioned  in  [3922/,  &c.]  ;  that  is,  by  changing  m,  a,  n,  e,  to,  &z;c. 
into  to',  a',  n',  c',  to',  S:c.,  i-esjjectively,  ivithout  (dtering  P,  P',  T~,,  or  the  divisor 
on' — 2?i.  In  this  way,  we  find  that  the  fourth  and  seventh  lines  of  [3911]  give  the 
second  and  third  lines  of  [3923]  ;  and  the  periodical  terms,  corresponding  to  the  fifth  and 
sixth  lines  of  [3911],  produce  in    c' d  to'    the  following  terms, 

7n2.o'2n'2         Cr/£/P\2       fdP'V^^       .     ^™    ,    ^     /dP\    /dP'\  ^) 

The  sum  of  the  expressions  [392.3/,  h]  depending  on  the  angle   2  T5,   represents  the  value 

of    c'  0'  to',    [3913]  ;   which  is  used  in  the  next  note.  [3923i] 


*  (2473)  The  expression  [3924]  represents,  for  the  planet  m',  the  terms  similar  to 
those  in  [3918,  3918'],  which  correspond  to  the  planet  tn,  and  are  derived  from  the 
function  [3917a].  The  similar  function,  relative  to  the  planet  to',  using  the  symbols 
T,  =  5n't  —  2nt-\-5^—2s,      JV'=n't -\- ^—-^^     is 


|2  Ô'  e'  +  2  e' 6  to'  .  5  /  —  e'.  (f3  to')2| .  sin.  TV  —  \2  e  0' zi' -{- 2  5 e'.  à  to'—  2  .5  s'.  S  e'\ . cos.  W. 


[3924«] 
[39246] 


112 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


If  we  denote  the  inequality  of  m',  depending  on  the  angle  2nt — ■in't-{-2; — 4s', 
[3925]  6  v'  =  K'.  sin.  (4  n'^  —  2  M  i  +  4  s'  —  2  E  +  5'), 


[3924c] 


By  the  inspection  of  [39076,  c,  a],  we  perceive,  that  o  c,  5zi,  become  equal  to  <)  ë ,  '3ra', 
respectively,  by  changing  the  elements  m,  a,  e,  he.  into  m',  a',  ë,  he,  iviihout 
altering  P,  P',  T5,  or  the  divisor  5n'  —  2n  ;  upon  the  principles  of  derivation 
used  in  [3923^].  By  this  method  of  derivation,  we  may  obtain  — ë.{5zi')^  from  [3917c], 
and  we  find,  that  it  is  equal  to,  and  of  an  opposite  sign  to  the  part  of  2  5'  c'  [3922n]  ;  so 
that  these  terms  destroy  each  other,  in  the  value  of  2  0'  e' —  c'.  (0  ro')^  ;  and  then  the 
other  part  of    2'5'e'   [3922/:;],  spoken  of  in  [3922o],  produces  the  following  expression  ; 


[3924rf] 


-e'.(<5ra')^ 


3m3.a3n3      (5m/a  +  2HtVa') 
(5)i' — 2n)3.  a''  m\/'a 


+ 


dp 

de' 


.cos.2T^ 


Now  if  we  represent,  as  in  [3913'],  by  5  s',  the  part  of  5  v'  [3846,  &c.],  depending  on 
the  angles  Tg,  2T^,  and  notice,  as  in  [3914a,  Sic],  only  the  chief  terms  of  5s'  depending 
on    Tj,    we  shall  get  the  following  value,  which  is  similar  to  [39146], 


[3924e] 


6e'-. 


15  m .  a'n'^ 


S-P.cos.T,  +  P'.sin.T,}. 


■(5n'— 2îî)a 

Multiplying  this  by    2  e' 5  to'  [3907c,  n],  and  substituting  the  values  [3917c?],  we  get 

/dP'-^ 


[3924/] 


[3924e'] 


[3924/1] 


[3994i] 


[3924*] 


dP 

t' 


'   à  ûî  .  f)  s  :=  Ti —  .  < 

+  [ 


(5?i'— 2îi)3 


■^■■(^ 


dP 

de' 


2T, 


.C0S.2T, 


We  have  very  nearly  5?i'=2w  [38 18c/],  and  n^(P^n~c?  [3709'];  multiplying 
these  two  ecjuations  together,  and  the  product  by  3  m^,  we  get  15  m^.  a'^  k'^=  6  vr.  a^  n^  ; 
substituting  this  in  the  first  factor  of  the  second  member  of  [3924/],  it  becomes 


15to2.  a'2?i'3 


3  m9.  a3  n3        2  711  \/a 


{5n'— 2/1)3         {5n'— 2îi)3.a'     m /a    ' 
and  then  the  sum  of  [3924c/,/]  becomes,  by  \vi'iting,  for  brevity, 


M^ 


3 nfi.  (t3 »3       {3mv/a  +  2mVV)_ 


(5ji'  — 2n)3.a' 


my' a 


i.2ï; 


2  <5' e' +  2  e' <5  i;i'.  <S£'  — e'.  ((5  îs' )2= 


+^.[P'.©-p.O].cos..r. 


Vf.  ii.  §  13.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        113 

and  the  great  inequality  of  m'  [3891]  by* 

^'=  —  H'.  sin.  (5 n't  —  27it  +  5s'  —  2s  +  Â'),  [3926] 

Again,  if  we  multiply  together  the  two  equations  [-SOOTc],  and  divide  the  product 
by  iJ\I\.e'  [3907n],  we  shall  get  an  expression  of  — 2ôe'.ôzi',  similar  to  [3917À;], 
»k',  a,  n,  e,  being  changed  into  m,  a',  ii! ,  e',  respectively,  without  altering  the  divisor 
5n' — 2n.  Adding  this  to  the  part  of  — '^t'h'-ui,  deduced  from  [3923A],  we  [3924?] 
find  that  the  sum  becomes  nothing  ;  and  the  term  of  e'  i5  '  ra'  [3923/]  produces  the 
following  expression, 

^p.(^^^+P^(l^^1.eos.2T, 

— 2e'ô'a'— 2(5e'.5w'=  — — T-;— — .' -—^, ^^^<  >.     [3924m 


-M-£)--m--^' 


2 


Multiplying     —M-.-oe'    [3907c]  by    —j^,     and  by    (5  s'  [3924e],  and  reducing,  using 
[3907a,  3917(/],  we  get 

rp.(^)+P'.(^)1.cos.2r, 
^^^•^'=ron'-2nf    ■<       -         ..^..  ..-    -  >;  [3924n] 


H-m-^-m---^ 


in  which  we  must  substitute  the  factor  [3924/t]  ;  then  the  resulting  expression  being  added 
to  [3924w],  using  M^  [3924*],  the  sum  becomes 


^'•■['■■('S)+^'-(S): 


.  cos.  2  7\ 


-|2e'a"V  +  25e'.ow'  — 2(5s'.5e'}=<(  \.  [39240 


-'=■[-■■©--•  (^: 


.sin.STs 

Multiplying  the  equation  [3924^']   by    sin.  W,    and   [3924o]    by    cos.  W,    then  adding     [3924p] 
the  products,  we  find  that  the  first  member  of  the  sum  is  equal  to  the  flmction  [39246]  • 
the  second  member,  reduced  by  formulas  similar  to  [3917o],  is 

which,  by  resubstituting  the  values  [3924i,  «],  becomes  as  in  [3924]. 

*  (2474)    If  we  interchange  the  elements  of  the  bodies  m,  m',   in  [3826],  and  suppose 
B  to  become  B',  and    i  =  —  2,    we  shall  obtain  an  inequality  of  the  body    m',   of  the 
form  [392.5].     Substituting     %  =  bnt—2nt-\-bz -2e,     ?F3=n7  +  £',   W'=nt-\-î—u/,     t^^^*^ 
we  find  that  the  expressions  [3925,  3926]  become,  respectively, 

àv'=K'.5m.{Ts—W^-{-B');  ^'=  — H'.sin.  (T5  +  J').  [3926t] 

VOL.  III.  29 


114  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Ce}. 

we    shall    find,     that    the    inequality    of     m',      depending    on    the    angle 
^nt  —  9n'i  +  4s  —  9/,     is  represented  by 

[3927]        6v'=\S^''''^''^^"^^'''\h'  K'.ûxi.ant  —  9n't  +  ^B—9^'—B'  —  7i'). 

m\/a  ^ 


These  may  be  reduced  to  forms  similar  to  [39206,  c],  respectively,  by  observing,  tliat 
the  term  2e'.sm.{n' t-^-s  —  zi),  in  the  motion  of  m' ,  similar  to  that  of  m  [3913''],  may 
be  developed  as  in  [3915],  and  will  contain  the  terms  2  (5  c'.  sin.  W —  2  e'  ^  w' .  cos.  W, 
which  may  be  reduced,  as  in  [3916/"],  to  the  form 

n  ,  and  by  the  usual  process,  as  in  [3916A,  i],  it  may  be  reduced  to  the  form  K'.^m.{T^—W'-\-B^). 
Now  if  we  put  B^=B'—zi',  and  W=W3  —  -^'  [3926a],  it  becomes,  as  in  [39266], 
iT'.  sin.  (Tg  — fFg-j- J5')  ;  so  that  by  substituting  the  value  of  Al^  [3907a],  we  shall 
have  identically,  in  like  manner  as  in  [39206], 

[39-26e]     K\àn.{T,-W,+B')  =  ^^l;^^^^^.^-(^^^ 

Putting  the  two  expressions  of  the  chief  terms  of  the  great  inequality  [3924e,  39266] 
equal  to  each  other,  we  get,  by  changing  the  signs, 

[3926/]  E'.  sin.  {T,  +  .5')  =  '^^:^,-\P-  cos.  T,-  P'.  sin.  T,^ 

The  identical  equations  [3926e,/]  are  similar  to  [39206,  c],  and  may  be  derived  from  them 
[.3926g-]  by  changing  m!,  a,  n,  e,  to,  J3,  B,  K,  H,  fV^,  into  m,  a',  n,  e,  -a',  A',  B',  K',  H',  W^, 
respectively;  also  multiplying  the  second  member  of  [3920c]  by  if-,  without  altering  the 
angle  T^ ,  or  the  divisor  (  5  n' —  2  n  ).  Making  the  same  changes  in  the  product  of  these 
two  equations,  and  in  [39216],  we  get  from  this  last  the  following  equation  ; 


15m9.o'3n3  3       L        \de  J  \de 

[3926.]    -àH'jr'.cos.(^3-22'.-5'-..';=-^^;^;^^.^_     ^ 


sin.(^3— 275— ra')  , 


This  equation  being  identical,  we  may  change       fV^  —  2T5,     into     IV^  —  2  T5 -\- 90'' ; 

then  multiplyine;  by      7p~, ,     we  find,  that  the  second  member  of  the  product 

^  •'     °     -^  2  ni  v/o  ^ 

becomes  equal  to  the  expression  [3924]  ;  and  the  first  member  becomes  equal  to  [3927]  ; 
[.3926t]     observing  that    W^-2T^  =  'int-9n' t'j-4e-9s'    and    15^^. a'^M'^^Gm^ a^n^  [3924§-]  ; 
therefore  the  expression  [3927]  is  equivalent  to  [3924]. 


VI.  ii.  §  14.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        115 

14.     The  nodes  and  inclinations  of  the  orbits  of  Jupiter  and  Saturn  are 
subjected  to  variations  analogous  to  the  preceding.     To  determine  them,  toe 
shall  observe,  that   c,  ç',    being  the  inclinations  of  the  orbits  to  a  fixed  plane, 
and  ^  6'  the  longitude  of  their  ascending  nodes,  we  shall  have,  as  in  [1338],      [3928] 
bj  reason  of  the  smallness  of   <p,    9',* 

7  .  sin.  n  =  (?'.  sin.  è' —  ç  .  sin.  è  ;  [3029] 

'/  ,  COS.  n  =  (p.  cos.  6' —  ip  .  cos.  é.  [3929'] 


Moreover,  from  [3906],  we  havef 

m'\/d 
in'\/a 


i .  (?'.  sin.  0')  =  —  5:^  .5.(9.  sin.  0  ;  ^3930] 

à  .  ((?'.  COS.  ù')  =  —  '^^^^  .5.((p.  COS.  Ô).  [3930'] 


The  subject  of  the  small  inequalities,  treated  of  in  this  article,  is  resumed  by  the  author     [3926A] 
in  the  fourth  volume  [9062,  Sic]  ;    where  he  notices  terms  of  the  order     m'^.  e^,     &c., 
which  are  omitted   in  [.3914c].      His  object   in  using  the  indirect  methods,  adopted  in  this      [392(5q 
article,  is  to  avoid  the  great  labor  of  a  direct  calculation  ;  assuming  as  a  principle,  that  these 
very  small  inequalities  may  be  determined  in  this  manner  to  a  sufficient  degree  of  exactness, 
for  all  the  purposes  of  practical  astronomy  ;  as  will  appear  from  the  minute  examination     f3926»i] 
of  the  terms  of  this  kind  in  [9041 — 9114]. 


*i 


(2475)  Comparing  the  notation  in  [1337',  3902],  we  get  â/  =  n;  tang.i|)/=:tang.7=y  [3929a] 
nearly;  hence  the  equations  [1.338]  become  p' — p=y.sm.n,  q — q  =  y  .cq?,.TI.  [39296] 
Now  on  account  of  the  smallness  of  9,  we  have  very  nearly  |?  =  9  .  sin.  â,  q=  o  .  cos. 
[1334];  and  in  like  manner,  for  the  orbit  of  m',  p' =  9' .  sin.  â',  q' =  ip' .  cos.  6 
Substituting  these  in  [3929J],  we  get  [3929,  3929']. 


[3929c] 


t  (2476)    The  variation    of  the    second    member   of  [3929],    arising   from   the   action 
of  the   body    m'  upon    m,    is  represented   by     —  (5 .  (  9 .  sin.  ê  ) ,     because    ç',   é',    do  not      [3030a] 
vary  by  the   action   of   m'.       The   variation  of  the   first  member  of  the    same   equation, 
usbg  the  characteristics    &,,    <S„,    as  in   [-3399',  -3904],    is     <5,,.  (7  .  sin.  n)  ;      hence    by 
development,  we  have 

—  S.{((>.  sin.  0  =  ^7-  sin.  n  +  7  .  J,,  n  .  cos.  n.  [39306] 

In  like  manner,  the  variation  of  the  second  member  of  [3929],  relative  to  the  action  of  the 
body  m,   which  does  not  affect    9,   ê,  is     ô  .  {tp.  sin.  ^)  ;    and  that  of  the  first  member  is 


116  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

From  these  four  equations,  we  deduce  the  following,* 

in!  \/a'  .  ^  .  •       ^  X  ) 

[3931]  &,==-^^^_ç-^^^,.{6y.cos.(n-é)-y.6n.sm.(u-ê)]; 

[3931']  cp5è  :z= jn^  a  c,     _  gjj^_  ^^  —  o)  +  y.^n  .  COS.  (n — ê)\  ; 


[3932'] 


[3930c] 


0)  h^  =      — .  "',     ,    ,  ,.Uy  .  sin.  (n  —  â')  +  7.6n.cos.  (n  — ô')L 
m  \/a  -\-  m  \/a    '  ^  /    ■    '  v  ^  > 

5^.(7sin.  n);     hence  we   get    [.3930fZ].        Substituting   successively    in    this   the   values 
[3906,  39306],  we  finally  obtain  [3930/],  as  in  [3930], 


[3930rf]  (5 .  (  ip' .  sin.  â'  )  z=  5,  y  .  sin.  n  +  7  •  <5,  n  .  cos.  n 

[.3930e]  =      £;^.|<5„7.sln.n  +  7.<S,,n.cos.n^      [3906]; 

[3930/]  =-£^.5.(9.sin.â)     [3930è]. 

[3930iir]    In  the  same  way,  we  may  deduce  [3930']  from  [3929']. 

[3931ff]         *  (2477)     We  shall    put,  for  brevity,       M= — ,'"^",  ,  ,,       Jf,  =  — 7  ^'',     -,  ; 

then    taking   the  variation   of  [3929],    relative  to   the  characteristic    5,     we   get,  by  the 
substitution  of  [3930],  the  following  equation, 

5.(7.  sin.  n  )  ^       <5  •  (  <?'•  sin.  Ô')  —  (5  .  (  p  .  sin.  Ô  ) 
[.39316] 

=  — ^^.5.(?.sin.é)— 5.(ç,.sin.â)  =  — ITT  •  5  .  (9 -sin.  â), 

(«V»  •'"7 

or 
[39316']  5  .  (  (p  .  sin.  ()  )  =  —  M7 .  5  .  (  y  .  sin.  n  ) . 

[39316"]    In  like  manner,  from  [3929',  3930'],  we  get      5  .  (  <p  .  cos.  ^  )  =  —  Jlf7  .  0  .  (  7  .  cos.  n ) . 
Developing  these  two  equations,  we  obtain 

[3931c]  i5  (p  .  sin.  Ô  -f  (p  (5  Ô  .  cos.  &  ==  —  M~  .  (^  7  •  sin.  n  +  7  .  5  n  .  cos.  n  )  ; 

[3931d]  ^  (p  .  cos.  â  —  (p  (5  â  .  sin.  0  =  —  .M- .  (^  7  .  cos.  11  —  7  .  5  n  .  sin.  n  ) . 

Multiplying    [3931c,  t/]    by      sin.  Ô,      cos.  ^,      respectively;    adding    the    products,   and 
substituting  sin.-  ^  -f  cos.^  â  ^  1 ,  sin.  n  .  sm.  â  +  cos.  n  .  cos.  â  =  cos.  (  n  —  Ô  ) , 


[3931e] 


cos 


.  n.sin.  é  —  sin.  n  .cos.  ô  =  — sin.  (n — é),        we  get  [3931].       Again,  multiplying 


[3931c,  rf]  by    cos.  d,    — sin..",    respectively;   adding  the  products,   and    making  similar 
substitutions,  we  get  [3931']. 

t  (2478)    We  may  compute  the  equations  [3932,  3932']  from  [3929—3930'],  in  like 
[3932a]     manner  as  in   the    last    note  ;    or  more  simply  by   derivation,    in    the   following   manner. 


VI.  ii.  >^  14.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         117 

Therefore  the  variations  of    ç,  è,  <?',  o',    depend  on  the  variations  of  7  and  n. 
We  have,  by  ^12,* 

(      (—].cos.(57i't—2nt  +  ôs'—2B) 
,.,,..  ,       (—).sm.(57i't—2nt  +  5e'—20 


(/  r  m'  \/a' 


+  (^ycos.(ôn't—2nt  +  5^'—2s) 


If  we  change     m,  a,  (p,  ê,  7,     into     ?»',  «',  ç»',  «',  — 7,     and  the  contrary  respectively,  in     [39326] 
the  equations  [.3929 — 3930'],  they  will  remain  unaltered,  as  will  be  evident  by  changing  the 
signs  of  the  two   first  of  these  equations,  and  multiplying  those  which  are  derived  from  the 

two  last  by  the  factor     —'^-       Making  the  changes  [3932&]  in  [3931,3931'],  which     [39.32c] 

are  deduced  from  [3929—3930'],  we  get  [3932,  3932']. 

*  (2479)    Substituting  the  values     <5„  7,   3„  n    [3900,  3901],   in  [3906e],   and   using, 
for  brevity,  the  symbols   T5  [3890i],  also      an  =  a~^,     a  n' :i=^ a' ~ ^ , 

M,  =  "''■  ° "+"^ •  "' "'  =  (!!LV^+J!^Vg:) ^       ^j        M  _,„,,„  „_(i!H^+_Z!^vV).„,-.„„^        [3933«] 

m'.an  m' \/a'  m  ^/a 

we  get 

The  divisor  5n' — 2n  is  introduced  in  5  s,  &c.  [1342,3899 — 3901],  by  the  integration 
relative  to  t,  spoken  of  in  [1341a.  &c.],  in  finding  p,  q,  s  [1341,  1342]  ;  where  the 
angle  T5  is  considered  as  the  only  variable  quantity  ;  the  very  small  terms,  of  a  different  [.39.33c'] 
form  or  order,  depending  on  the  variations  of  the  elements,  which  enter  into  the  second 
members  of  [1342,  he,  39336,  c],  being  neglected.  If  we  again  resume  the  differentials 
of  the  expressions  [.3933è,  c],  upon  the  same  principles,  we  shall  get 


d 


[.3933rf] 


^^-M3..'.an.^(4^).cos.T,-Q.sin.T,^; 

^)  .  sin.  T,  +  (^)  .  cos.  n^ .  [393:3.] 

[3933/] 


rf.{6n)  ,,      m'.an    (  /d  P 

— ; — =  —  Mg. . 

dt  7 


These  equations  are   equivalent  to    [3933,  3933'],    omitting    the  characteristic    S,    which 
merely  signifies,  that  the  calculation  is  restricted  to  terms  depending  on  the  angle  Ts  [3893']. 

VOL.  III.  30 


118  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

r3933"l     Hence    we    deduce,    by   neglecting  periodical    quantities*   ivhose    effect   is 
insensible,  and  observing  thatf 


*  (2479a)  If  we  compare  the  expressions  [3842,  4401]  with  the  numerical  vahies 
[SPSSg']  of  e'%  e",  y,  or  tang.  7  [4080,  4409],  we  shall  easily  perceive,  that  the  terms  of  P  [3842], 
depending  on  7,  are  not  a  thirtieth  part  so  great  as  some  of  the  tenns  depending  on  e",  e"  ; 
therefore  the  periodical  inequalities  depending  on  the  variation  of  7,  will  evidently  be 
much  less  than  those  arising  from  the  variations  of  c'",  e".  Now  from  the  computation 
made  in  [4438,  4496],  it  appears,  that  these  last  inequalities  are  nearly  4'  and  9'  ;  hence 
it  is  evident,  that  we  may  neglect  the  periodical  quantities  spoken  of  in  [3933"]. 


13933/t 
[3933i] 


[39346] 


[3934c] 


[3935a] 
[39355] 


t  (2480)    Dividing  [3842]  by  a',  and  taking  the  partial  differentials  relatively  to  7,  we  get 
[3934a]  ^'-  (^)  =  2  M^'\  e'  7  .  sin.  (  2  n  +  «')  +  2  M^^\  e  7  .  sin.  (  2  n  +  ^  )  ; 

m'.  ('^]  =  2  M^».  c'.  sin.  (2  n  +  ^j')  +  2.¥'5).  e  .  sin.  (2  n  +  -^ï). 
\0  7^  / 

Multiplying  the  second  of  these  equations  by  7,    it  becomes  equal   to  the  first  ;    hence  we 
get,    by  dividing  by   m',      7./-— -j  =  (- — j.         In    like  manner,    from    the   values    of 

m'.ct'P'    [3843],   we  obtain        y  .(       .,    j:^(- — j;  dividing    the    first    of    these 

expressions  by  the  second,  we  get  an  equation,  which  is  easily  reduced  to  the  form  [3934]. 

t  (2481)  To  obtain  the  effect  of  the  variations  of  P,  P',  ,?,  ^',  in  dy  [393-3],  we 
may  proceed  in  the  same  manner  as  we  have  done  in  notes  2461,  2462  [3909a,  &ic.],  in 
finding  the  variations  of  de,  d^.  In  the  first  place,  we  must  substitute,  as  in  [3908a], 
^,  1^'    for    nt,    n't,   in  [3933],  and  use  the  symbols  [3933»];    hence  we  get 

rf7  =  _.;^f8.m'.anrf^^(^).cos.(.5^'-2^^-5s'-2.)-(î^).sin.(5^'-2^+5.'-2£)^. 


Substituting  in  this  the  values  [3909f?],  we  get  the  following  expression,  which  is  nearly 
'"  similar  to  [3909e],  changing   e    into    7,    &:c.,    and  writing,  as  usual,    dSy   for  Sy, 

Ç        /dP\  /dP'\  ') 

d5yz=       Ma  ■  m'.  andt .  <  —  (  -—  ) .  cos.  7^  +  (  —r~  ) .  sin.  T5  f 

C      \dyj  \dy  J  > 

[3935c] 

+  M^.m'.andt.{?>^'—2]V)  Âi^-^Vcos.  r5+('~)  .sin.  7^^  . 

The  variation  of  this  expression,  arising  from     i5  e,   '5  w,    (5  e',    (5 13',   5y,    5  n,     in  the  two 
first  terms,  may  be  found  as  in  [3909e — fc]  ;  or  more  simply  by  derivation,  in  the  following 


VI.  il.  §  11.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         119 

3 »i'2. gg ?i3    (my/a-f  wtVa')    (5my'a+2mVa')         (        /'<'^'\_p'  {iJL\  \ 
'{ân'—^nf'  mVa'  '  ?nV«'  '        (         Xd-y)  Kdj/S 


<5r  =  - 


+ 
+ 


5  n' —  2  )i  m  V"' 

mm'.aa'.nn'   [mi/a-\-m'\^a') 
'Sn'— 2^" 


f/rfP'N     /ddP\        {dP\     /rfrfP'N) 


+  mVa')         ^  f''P'\    f'ldP  \_fdP\    (ddP'\  }  _ 
^-V^^  "^^  i  Vrf«^/  'Ue'rf"//         \de')'\de'dy)\' 


Inefiuiilily 
ill  tlin 
inclinutioii 
of  the 
orbits  of 
Jupiter  mid 
Siituni. 


[3935] 


manner.  If  we  change,  in  d  <)  c  [.3909e],  e  into  y,  zs  into  n,  and  the  contrary  ;  also  [3935;;] 
m'  into  Ms-m',  without  aUering  the  values  of  P,  P\  JY,  JV',  T5,  e,  z/,  he; 
we  shall  find,  that  this  expression  of  d5  e  becomes  equal  to  that  of  do  y  [3935c]  ;  and 
by  making  the  same  changes  in  the  other  expressions  of  d5e  [3909A,  /c],  we  shall  get  the 
similar  values  of  day.  After  making  these  changes  in  [3909/c],  and  putting,  for  brevity) 
M^=^Mg.m'.an  [-39330],  we  may  alter  the  arrangement  of  the  quantities,  so  that  the  [-39.356] 
ternis  depending  on  the  same  differential  coefficient  may  be  connected  together,  and 
we  shall  get 

dh=      ^/9.rf^(5JV'-2JV).[('^^).cos.r,+  (^).sin.T5j 

+  JI/g.^/^f^Y(-^e.cos.T5-cfe.sin.T,)+J»f9.(/^(^^y(r5e.sin.7;-efc.cos.r5) 


+  ^ig.rft.['^).(-5e^cos.^5-cW.sin.^3)+^/o.r/^('^^V(^e'.sin.T5-e'^^'.cos.^5) 


de'd 


dedy 
\dedy 


[3935/] 


-^M,.dt.  (^^).(-57.cos.2'5_76n.sin.r5)+M9.(/^-(^).('5r.sin.T5-y5n.cos.r5) 
_JI/.../^5n.^(^i^).sin.T.+  ('^).cos.T4. 


We  may  neglect  tlie  fourth  and  fifth  lines  of  this  expression, 
values  [3907O-]  in  the  fourth  line,  it  becomes  equal  to     —  , 


For  if  we  substitute  the 
multiplied   by  the  terms  in 


[3935e-] 


the  first  member  of  [3934],  and  is  therefore  equal  to  nothing.  IMoreover,  by  using  the 
value  of  ^  n  [3907 fZ],  we  find  that  the  lower  line  of  the  expression  [3935/]  becomes  of  a 
similar  form  to  tiiat  in  the  second  member  of  [3909a;]  ;  the  partial  difl^erentials  of  P,  P' 
being  taken  relative  to  y,  instead  of  e.  Hence  we  find,  as  in  [3909y],  that  this  line 
of  [3935/"]  depends  upon  xhe  periodical  quantities  sin.  2  T5 ,  cos.  2T5,  which  are 
neglected  in  the  present  calculation  [3933"] .  The  three  remaining  lines  of  the  expression 
[3935/]  being  reduced,  and  integrated  relatively  to  t,  produce  respectively  the  three  lines 
of  the  expresson  of  ^7  [3935].      For  if  we  compare  the  first  line  of  [3909/t],  multiplied 

Mg=-^    [3933«],  with  the  first  line  of  [3935/],  we  shall  find  that  they  become 


[-393.5A] 


by 


[3935i] 


identical,  by  changing  the  partial  difierentials  relative  to   e  into  those  relative  to  y  ;    hence 


120 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél 


Inequality 
in  the 
place  of 
the  node. 


[393G] 


<5n: 


3m'2.a2ji3     [nn/a-^m'y/a')  [5m\/a-\-2m'^/a'] 
(5n' — 2n)2.y  7n'\/a'  m'^a' 


+ 


73  «2 


{nn/a~\-m'^a') 


(5n'— 2n).y  m'^a' 


mm' aa' nn'    {m\/a-\-in'y^a') 


(5n' — 2n).y  m'\/a' 


\de  J'  \dedy  )  ~^  \d7  )  '  \d7d 


edy  J 
/ddP 


\d  e 
dP' 

7 


ddP' 

7 
ddP 

7 


,/dP\      'ddP\     ,    fdP'\     /ddP'\ 

/dP\     fddP\         fdP'\     (ddP 
\dt'  )'  \de'dy)    '    \d7)  '  \de'd 


'     \de'dyj 
'    .    (dP\     /ddP\        /dP'\     /ddP'\ 


[3935it] 


[3935/] 


[3935j?i] 


[3936a] 


[39366] 


[3936c] 


[3936rf] 


[3936e] 


we  obtain  the  coefficient  of  t,  in  the  term  of  5  y,  depending  on  the  first  line  of  [3935/"],  by 
multiplying  the  first  line  of  [3910J,  which  is  derived  from  the  first  of  [3909A:],  by  M^  [3935i], 
and  changing  the  differential  divisor  de  into  dy,  as  in  the  first  line  of  [3935].  Again, 
substituting  the  values  [3907e]  in  the  second  line  of  [3935/],  and  using 


Mg        m'  2.  «2  jtS    {m\/a-\-  my  a') 


[3933a,  3907o], 


we  get  the  second  line  of  [3935]. 

Mg 


m'  \/a! 
Lastly,  substituting  [3907/],  and 


mm.  aa  tin 


[m\/a-\-m!\/a!^ 
m'  \/a' 


[3933a,  3907a], 


Mç^  5  n'—  2 II 

in  the  third  line  of  [3935/],  we  get  the  third  line  of  [3935]. 

*  (2482)  We  may  compute  (5n  from  [3933e],  in  the  same  manner  as  we  have 
found  h  y  [3935]  from  [3933f/]  in  the  last  note  ;  or  we  may  use  the  principle  of  derivation; 
observing  that  the  expressions  of  dy,  ydïl  [3933(Z,  e]  have  a  relation  to  each  other, 
which  is  similar  to  that  of  de,  ed-m  [3908c,  (/].  Moreover  the  former  values  may 
be  derived  from  the  latter,  by  changing  e,  «,  &tc.,  into  y,  n,  Sic,  respectively,  as 
in  [3935f/]  ;  therefore  we  may  derive  the  expression  of  (5  n  from  that  of  5  y,  in  the  same 
manner  as  we  have  derived  «îw  from  8  e,  in  note  2462  [3910cf,  &ic.].  Proceeding  now 
as  in  that  note,  we  shall  find,  by  changing  e  into  7,  &:c.  in  the  terms  [3910p,  q],  and 
reducing  as  in  [3910?-],  that  these  terms  depend  on  the  periodical  quantities  sin.  STs, 
cos.  2r5,  which  are  neglected  in  [3933"]  and  in  [3935/(].  In  the  terms  depending  on 
the  factor     5JV'  —  2  JV,     we   find,   by  proceeding  as  in    [39107i:],   that  we  must  change 


\dy) 


nito     - . 

7 


— —  )  ;        and   by    making   these 


(dP'\  ,      fdP'\      .  1    /dP' 

changes  in  the  first  line  oî  S  y  [3935],  we  get  the  corresponding  terms  of  ^n  in  the  first 
line  of  [3936].  The  remaining  terms  corresponding  to  those  which  are  computed  in 
[3910m — 0],  depend  on  the  second  differentials  ddP,  ddP',  and  maybe  computed 
from  the  second,  third,   and  fourth  lines  of  [3935/];   changing    T5    into     T5 — 90'',    as 


VI.  ii.  {s  15.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        121 

15.  If  we  wish  to  determine,  for  any  time  whatever,  the  elements  of  the 
planetiuy  orbits,  we  must  integrate  the  differential  equations  [1089,  1132], 
by  the  method  explained  in  [1096,  Sic.]  ;  but  in  our  present  ignorance 
of  the  exact  values  of  the  masses  of  several  of  the  planets,  this  calculation  '■  "  '' 
would  be  of  no  practical  use  in  astronomy  ;  and  it  becomes  indis])ensable  to 
notice  the  secular  variations,  depending  on  the  square  of  the  disturbing 
force,  which  we  have  just  determined  ;  since  they  are  very  sensible  in  the 
orbits  of  Jupiter   and    Saturn.       These   variations    increase    the    values   of 

,     ,     -=— ,     -f-,     — —  ,     &c.,    relative  to  these  two  planets,  by  the 

at  at  at  at         d  t 

.  .      ^         h'\Se"'       I'^iTu'"          l''\Se'"        h".ôu"  p^.&ca'"    ,    q''\Sè'"'  „ 

quantities*       __+-^; ~;     ii___  +  i__;      &c.,      [3938] 


in  [3910a — d],  and  substituting  the  values  [3907e — gl  ;  by  this  means  we  shall  obtain 
the  corresponding  terms,  which  are  to  be  multiplied  by  —  in  d 5u  ;  or  by  — 
in    Su,    namely, 

A/P\     /ddP\    ,    /dP'\     /ddP'\-)    ,    Ma     (,/'dP\     /ddP\    ,    /dP'\     (ddP 


[393G/] 


\     /ddP\        /dP^\     /ddP'\~)        Ms_    WdP\     /ddP\ 
•Ml  ■  l\de  J'  \dedy  )  ^~  \d7  )  '  \dedy  )\~^  M2     i\de')'  \de'dy)    '    \de'  J  '  \de'dy 

Mg     WdP\     /ddP\         /dP'\     /ddP'\ 
+  .¥3  ■  l\dy  )  ■  yi^J  +  Wr  /  '  \  dy^   ) 
Substituting  in  this  the  values  [3935/,  m],  also 

17-=  5  K   ■     o    +  '~^> — S —  C  •  T-r, [3933a,  3907oJ,  [3936g-] 

we  get,  by  a  slight  reduction,  the  second  and  third  lines  of  [3936]. 

*  (2483)    The  equations  [1022],  corresponding  to  Jupiter  and  Saturn,  are 

Ai"  =  e'\  sin.  ra'"  ;         I"  =  é\  zo%.  v>"  ;         A"=e\  sin.  to"  ;         /"=  e".  cos.  ■b".  [3938o] 

Taking  the  variations  of  these  quantities,  relatively  to  the  characteristic  i5,  used  as  in  [3938'], 
and  then  substituting  the  values  of    sin.  ra'",    cos.  ra'",    &ic.,   deduced  from  [3938^],  we  get 

<5  Ai'=  5  e'".  sin.  ra'"  +  e'".  <5  w'\  cos.  to'"=  rîe'"  . -|^  +  e'\  cS  to-". -^  ;  [.39386] 

J  /*"  =  5  e'".  cos.  TO  —  t" .  5  to'",  sin.  to'"  =  ô  e'"  .  ^  —  e'".  h  to'".  —  ,    &c.  [3938c] 

e'"  e'" 

The  secular  part  of  any  one  of  the  quantities   (5e'",  (Îto'",  he,  5ra"  [3910,  3911,  3922,  3923], 
may  be  put  under  the  form    ht'^^At;    A  being  a  function  of  the  elements  of  the  orbits, 

of  the  order    m'^.      Its  differential,  divided  by    at,    gives     ——  =^A== — ;     observing,     [39,'3S(/] 

that  the  variations  of  A  may  be  neglected,  because  they  are  of  the   order    m',    and  are 

VOL.  III.  31 


122  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

considering  only  in  6  é" ,  6  n'%  the  quantities  proportional  to  the  time  t, 
^'"'  J  determined  in  the  preceding  articles.  We  must  substitute,  in  these  last 
quantities,  the  values  of  e",  sin.  ~",  cos.  ra'',  &c.,  expressed  in  terms 
of  h",  /'",  &c.*  The  diiferential  equations  [1089]  will  then  cease  to 
[.?939]  be  linear  ;  but  it  will  be  easj  to  integrate  them  by  known  methods  of 
approximation,  when,  after  the  lapse  of  many  centuries,  the  exact  values 
of  the  planetary  masses  shall  be  known.  In  the  present  state  of  astronomy, 
it  is  sufficiently  accurate  to  have  the  secular  variations  of  the  elements  of  the 
orbits,  expressed  in  a  series  ascending  according  to  the  powers  of  the  time, 
carrying  on  the  approximation  no  farther  than  to  include  the  second  poAver. 

We  have  seen,  in  [1114",  1139'"],  that  the  state  of  the  planetary  system 
is  stable,  or  in  other  words,  that  the  excentricities  of  the  orbits  are  small, 
and  their  planes  but  little  inclined  to  each  other.  We  have  deduced  this 
important  result  of  the  system  of  the  world  from  the  equation  [1153],t 


[3940] 


[3940'] 


[3941]  constant  =  (e-  +  o"")  .  m  \/a  +  (e''  +  <?'-)  .  m'  \/a  +  &c.  ; 

for    the    second   member  of  this   equation  being  small  in   the   present   state 
of  the  system,   it   must  always   remain  so  ;    consequently  the  excentricities 
r394'>l      ^^^  inclinations  of  the   orbits  Avill   always  be  quite  small. J      We  shall  now 
prove  that  the  differential  of  the  preceding  equation  [3941], 

[3943]  (cde  +  ^dv)  .m^a-\-  (e'  d  e' +  <f>' d  v')  .  m'  \/a'  +  &c.  =  0 , 

multiplied  by  He'",  which  is  of  the  order  m'^,  producing  terms  of  the  order  m'^.  For  a 
similar  reason,  we  may  nesrlect  the  variations  of  ^  ,  —  ,  Sic.  in  findine  the  differentials 
of  [39386,  Sic.].     Hence  the  differential  of  the  last  expression  in  [3938e],  divided  by  dt,  is 

,.^^t,o  -,        ^^f^'"  doe'"      h'"      ,        .      rf(5wv     Jiv  ^jiv      7jiv  iT^iv      liy  r„„„„-,  .      . 

[3938e]     --—  ^  — — .  —  +  e" — -—  .-  =  —-.-_  -f  e'' . -,      as  m  [3938],  omitting  the 

dt  dt       e"    '  di      e'"  t       v    ^  t       e'"  l  J'  t> 

characteristic    6   in   the  first  member.      In  a  similar  way,  we  may  obtain  the  other  values 

~dT'     'dJ 


[3938/]     [3938]  from   [3938c,  fee]  ;  also  the  variations  of    "^  ,    '^  ,    &c.  from  [1132,1032]. 


*  (2484)    The  equations  [3938a]  give     e'^' =  ^{h'^^  +  l'^^),     e"  =^^{Jc'' +  l"""),     as 
[3939a]     in  [1108];  which  are  to  be  substituted  in  [3938];  and  when  the  resulting  quantities  are 
added,  respectively,  to   the   second   members   of  [1089,  1132],    they  cease  to  be  linear 
in    A"',    l",   he,  as  is  observed  in  [3939]. 

t  (2485)    Neglecting  terms  of  the  order  (p*,  we  may  put   tang.^<p=fp^  and  then  [1153] 
r3940a]     becomes  as  in   [3941]. 

[.3941a]        t  (2486)  This  must  be  understood  with  the  restrictions  mentioned  in  note  762  [1 1 14a,  &c.]. 


VI.  ii.  v^l5.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        123 


[3943'1 


[3943"] 


obtains  even  when  we  notice  the  secular  variations  of  the  elements  of  the  orbits 
determined  in  the  preceding  articles  [3910,  3922,  3935,  &lc.].  Hence  it 
will  follow,  that  these  variations  do  not  affect  the  stability  of  the  planetary 
system.  To  render  this  evident,  it  is  only  necessary  to  prove,  that  if  we 
represent  the  mass  of  Jupiter  by  m,  that  of  Saturn  by  ??j',  and  put 
ie,  âe',  Ô!?,  à  if,  respectively,  for  the  secular  variations  of  e,  é,  <p,  ip', 
which  were  found  by  the  preceding  calculations,  we  shall  have 

(e  6  e  +  ?  â  ?)  .  m  \/«  +  (e'  6  e'  +  9'  ô  ?')  .  m'  /a'  =  0 .  [3944] 

If  we  substitute,  in  the  function  (pa©  .  m^/a  + 'P'^'P'- w*'v/^<')  the  values 
of    «,   6ç,    9',   6ip',    given  in  the  preceding  article,  it  becomes* 

m  m' y/a  a 


[3944'] 
yày  ;  [3945] 


[394Gn 


m  s/ a  -j-  m' y/n' 

which  changes  the  equation  [3944]  into 

,      ,      ,      ,       /    /  ,    ,        mm'\/aa'  . 

eôe.mi/a-Jreôe.mi/a'-\ ; — ,     ,    .  , .  y  ôy  =  0.  [3946] 

^  m  \/a  -\-  m  \/a  ■' 

We  shall  now  commence  with  the  consideration  of  the  first  line  of  the 
expression  of  ie  [3910],  which  becomes,  by  the  substitution  of  a^n^=\ 
[3709']  ,t 

-5  6=-  r^, ;    ,7     ,  ;      \nt.]P.  (---]— P'.  (--)[.  [3947] 

*  (2487)    Multiplying  [3931,3932]  by    <f.7n^a,    (p'.mYa',    respectively,  and  adding 
the  products,  we  get 


/>**  ■( 


,       ,      ,     ,//''     mmVaa'       ^      -^r  •  1  — P  •  cos.  (  n  — ^  +  o'.  cos.  (  n  — é')L 
^/..<p^^  +  q)^9=  _^  .<^ V.  [3944a] 


m^a  +  nWa'     (  ^  y  S  H  .  {  ^  .  sin.  (  H  —  â)- 9'.  sin.  ( 


n-é')\  ) 


Now  multiplying  [3929,  3929']  by    sin.  n,    cos.  11,    respectively,  adding  the  products,  and 
putting     sin.^n  +  cos.^n^l,    sin. n.sin.â'-f  cos  n.cos.â'  =  cos.(  11  —  Ô'),  8ic.  [24]  Int.,     [39446] 
we  get  [3944c].      In  like  manner,   multiplying    [3929]   by    — cos.  n,    and  [3929']  by 
sin.  n,    and  reducing  the  sum  of  the  products,  it  becomes  as  in  [3944f?]  ; 

(?'.  COS.  (  n  —  è')  —  9  .  COS.  (  n  ^  é  )  =  y  ;  [3944c] 

(?'.  sin.  {U  —  é')  —  cp.  sin.  (  n  —  â  )  =  0 .  [3944(i] 

Substituting  these  in    [3944a],    it   becomes   as    in    [3945]  ;    and  by  this    means  [3944] 
changes  into  [3946]. 


t  (2488)    Substituting     a^  n^  =  -    [3946']    in  the  first  line  of  5  e  [3910],  it  becomes 

as  in  [3947].      Again,  substituting    a^  n^  =  n    [3946'],    in  the  first  hne  of    oe'  [3922],     [394eo] 
we  get  [3943]  ;  in  like  manner,  the  first  line  of  [3935]  becomes  as  in   [3949]. 


124  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

In   the  second  place,   we   shall   consider    the   first   line    of  the   expression 
of    àé   [3922], 

[3948]  ,  V  _        .3m.(5,V«+2mV«')  C        /rf^N  /dP\  ) 

Lastly,  we  shall  notice  the  first  line  of  the  expression  of  5  y   [3935], 

[3949]  3m'.(5mv/«  +  2mV«')    (>V«  +  mV»')    ^^  ^    (^    /^^^        p'   /l^\? 

(5n'— 2h)2.  «^/f/       ■  mV«'  '  (     '  \'h  J  'vhj\' 

If  we  notice  only  these  terms,  we  shall  find* 

,      ,     ,      ,       /    ,  /   ,        mm'\/na' 
e  à e  .  m\/a  +  e  à  e .  m  u a  -\ — — — ,     ,   ,  ,  .y&y 

*  *  m  \/a  ~\-  m  \/a' 

[3950] 

3mm'.(5m\/f>  +  2m'\/a')  \  '  L  '\d7  J '^  ^  '  \de'  )  ~^"'"  \J^  )j 

[3950]      Now    P,    F',    being    homogeneous   functions  of     e,    e',    y,     of  the    third 
dimension,  we  shall  havef 

therefore  the  equation  [3950]  will  become 

,,,,,,,           mm'\/aa'  ^ 

[3952]  ede  .m\/a  +  e  àe.m  i/a  -i ; — .     ,   ,  ,  .y6y  =  0. 


*  (2489)    Substituting  the  terms  of  5e,  6c,  6  y  [3947,3948,3949],  in  the  first  member 
of  the  expression  [3946],  it  becomes  as  in  the  second  member  of  [3950]. 

f  (2490)    The    expressions  of    P,   P'    [3842,  3843],    are  evidently  homogeneous  in 

e,    e',    y,    and    of    the   third   dimension.       Now   the    theorem   in    homogeneous    functions 

[3950a]     [1001a],    by    putting       n  =  3,      a  =  e,      a'^e',      a"=y,      A"^=P,       becomes    as 

in  [3951];    and  if  we  put     ^''':=  P',    we  get  [3951'].      Substituting  these  in  [3950], 

we  get  [3952]. 


VI.  ii.  §15.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         125 

We  shall,  in  tlie  next  place,  consider  the  followhig  terms  in  the  fourth  line 
of   6e    [3910],* 

^        {5n'-'in).a'l\de  )\de'i    )       \de  )  \  dt"~  )^\dy  )'\dedj  )      [d  y  ) '\d  e  dyJS  '  ^^ 

and  the  terms  in  the  third  line  of    6e'    [3922], 

,, mm'.t  ^/rfP'\   /ddP\      fdP\  /ddP'\      fdP'\  /  ddP  \      /dP\/ddP'\-i 

"^  —  [5n'—%n)Vaa''l\d  c  )\jid^j~\J7  J\J777)^\1^  jXdTd^r^JTy  )'\^^  ^1 

also  the  terms  in  the  second  line  of   &  y    [3935], 


.  m'2.<  (mt/a+)«Va')     i/dP'\      /ddP\        (dP\     (ddl 

['yii—'in).a'         m'^a'  C\de  J  '  \dedyj        \de  J  '\ded 


m'^.mt  j        \  de  J 


fdP\     C       /ddP'-^ 


ddP'\         ,   (ddP'\  tddP'\~i 

dti    )+^-  Vrferfe'J+^"  \dtdy)\ 

(bn!—2n).\/a'\     ,    /dP'\    C      /ddP\    ,     ,    /ddP\    ,        /ddP\-) 

I  -^[-djji'idûyJ+'-UVdVj+^i-d^n 

fdP\     i       /ddP'\    ,     ,    fddP'\    ,         /ddP'\} 

-w}-r\iTj^)'^'-Wd^)+^-[ih^)s 


[3955] 


we   shall  have,  by   noticing  these  terms  only,  and  observing  that  we  have, 
as  in  [3934], 

/'dP'\     /ddP\         /dP\     /ddP'\ 

/      ,      ,      ,       ,    /  ,   ,        m  m'\/a  a' 

eôe  .m\/a  +  e  6e.  m  i/a  -j ; — ;     ,   ,  ,  .y6y 

'!^^  5,  (^-\+c-  r^^^Uy  i'^-^\l\ 

de  )'l       \de^   )^^-\dede')^''-\dedy)S    \ 


;t  [3957] 


*  (-2491)     The    part    of    (5  e     in    the    fourth    line    of    [3910],    by    tlie    substitution    of 

«2n2^-  [,3946'],  becomes  as  in  [.395.3].      Again,  we  have    an  =  ^  ,   a'ti=—   [.3946'], 

a  a',  n  «'=  — — -  ;     substituting  this  in  the  tiiird  h'ne   à  e'    [3922],   it  becomes  as  in    [3954]. 

Lastly,  substituting     a^  n^  =  -   [3746'],  in  the   second   line  of    f5  y    [3935],   it   becomes     [39526] 
as  in  [3955]. 

t  (2492)    Adding  the   two  terms  [3956]    to  the  two  terms  hettveen  the  braces,  in  tlie 
last  factor  of  the  expression  of   '5  y    [3955]  ;  it   becomes  of  a  symmetrical  form  with  the     [3957o] 
values  of    5e,    a  e'   [3953,3954].      Substituting  these  values  of    &  e,  he',    &y,    in  the  first 
member  of  [3957],  and  connecting  togetlier  the  terms  depending  on  the  same  factors  of  the     [3957i] 
first  order,  it  becomes  as  in  the  second  member  of  [3957]. 

VOL.  III.  32 


126  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[3957']     ( )     and      ( )       are  homogeneous  in    e,  e',  7,    and  of  the   second 

\d  e  J  \de  J 

dimension  ;   hence  we  have* 


<^ 


dP_ 

in 


fcJdP\     .       ,    fddP\     .  fddP\ 

/ddP'\    ,     ,  /ddP'\    ,        /ddP'\        _     /dP'\ 
[3958"]     Moreover      (  - — ■  ) ,     (  ^ )      are  homogeneous  in    e,  c',  7,    of  the  second 

\«7/      \'h  / 

dimension  ;   therefore  we  have 

hence  we  find,  by  noticing  these  terms  only,! 

[3960]  eôe.m^a  +  e'ô  e'.  m'  k/o!  +  -^p''^y  ,.76-^  =  0. 

^  ^  m  \/a  -f-  m  \/a 

Lastly,    we    shall    consider    the    following    terms    of      f>e,X      included    in 


[3958a] 


[39586] 


*    (2493)     It    evidently    appears    from    tlie    values    of     P,     P'    [3842,   3843],    that 

/dP\       fdP'\       /dP\       /dP'\  ,  ...,-, 

(  -—  j ,     (  — —  j ,     (  7~  )  )     (  ";; —  )      îire  homogeneous  tunc.tions  m   e,  e  ,  7,  of  the  second 

degree,  corresponding  to  the  formula  [1001a,],  supposing     «  =  e,    n'=e,    a"  =  y,    m=2. 

If  we  put,  in  this  formula,      ^(''=^-— j,     we  get   [3958];     and     ^"i=r-_j       gives 

[3958'].     In  like  manner,  by  putting  successively,     ^"i  =  (  — j,     ^'■'  =  f-—j  [1001a], 
we  get  [3959,  3959'].  ^ 


t  (2494)     Substituting  the  values  [3958,  3958']   in   the  first  and  second   lines  of  the 
[3960a]     second  member  of  [3957],  we  find  that  these  terms  mutually  destroy  each  other.      In  like 
[.30(106]     manner,  the  terms  in  the  third  and  fourth  lines  of  [3957],  are  destroyed  by  the  substitution 
of  [3959,  3959']  ;  and  the  whole  expression  becomes  as  in  [3960]. 

t  (2495)    Substituting     aa'.nn'= [3952«],    in    the    last    lines    of    the   values 

[3061a]     of    Sc,    5  y    [3910,3935],    we   get    [3961,3963],    respectively.       Putting     a'^n'~=-, 
[3952o],  in  the  second  line  of    &  t     [3922],  we  get  [3962]. 


VI.  il.  §  15.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         127 


the  seventh  line  of  [3910], 


m  m'.  I 


WdP'\  fddP 


/dP\  ('i'^P'\_,(dP'\  fddP  \       /dJl\fddP'\) 

{r}n'—'în]Vaa''l\,le'J\dede'J      \de' j\de  de' )'T'\d  y  )\,ledy  j\,ïi  )\77d^)  )' 

and  the  terms  of    6e',    in  the  second  line  of  [3922],   namely, 
g  .^ »A< W'^P"\  fddP\      /dP\  /ddP'\      /dP^\  /ddP\      /dP\  /ddP'\-) 

also  those  terms  of    o;. ,    in  the  third  line  of  [3935], 


5y  = 


(my/a  +  mVn')  W'^fl\     (ddP\ (dP\  I'ddP' 


(.5?i' — 2n).^/aa'  m'\/a'  '  '  '  \\dt' J  '  \de' dy 

Hence  we  shall  have,  by  noticing  these  terms  only,* 


dP\  /ddP'\  -) 
de' J\de'dyJ  )  ' 


,      ,      ,      ,       ,     ,  ,    ,        mm' Wa a' 
e  ie  .  m i/a  4-  e  ôe.  m  wa  -\ —- — , .  -.  5 7  =  0 . 

Therefore  the  equations  [3946,  3941]  hold  good,  even  ichen  ive  notice  the  terms 
depending  on  the  square  of  the  disturbing  force  [3910,  3922,  3935]. 


*  (2496)  Substituting  the  values  of  à  e,  Sc',  5  y  [.3961—3963],  in  tlie  first  member 
of  [3964],  and  reducing,  as  in  the  preceding  notes,  by  means  of  formulas  similar  to 
[3958 — 3959'],  we  shall  find,  that  the  terms  mutually  destroy  each  other.  But  without 
taking  the  trouble  of  writing  down  these  formulas  at  full  length,  we  may  abridge  the 
calculation,    by   the    principle   of  derivation,    in    the    following   manner.       If  we   multiply 


the  values  of    6e,    5e',   5  y  [-3953,  .3954,  3955],  by  the  factor 


m\/a 
III'  y/a' 


and  in  the  terms 


whicli   are  connected  with   the   two  differential  coefiîcients     (  — —  ) ,    (  -—-  ] ,     change  the 

partial  differentials  of  P,  P',  of  tlie  first  order  relative  to  de,  into  those  relative 
to  de;  and  in  the  differentials  of  the  «ccowfZ  on/cr,  d  e^  into  de  de',  de  de'  into  de'^, 
d  e  d  y  into  d  e'  d  y,  the  other  differentials  being  unchanged  ;  we  shall  obtain  the  three 
expressions  [3961,  3962,  3963],  respectively.  The  same  changes  in  the  partial  differentials 
may  be  made  in  [3958  3958'];  as  is  evident  by  putting,  in  [1001«],    a  =  e,  a'=^t',  a"^y; 

and  then    .7'"  ^  f  —  j ,    to  obtain  the  equation  corresponding  to  [39.58]  ;  also  ./2®==(-T-r  j , 

to  obtain  the  equation  corresponding  to  [3958'].  To  render  the  expression  [3963] 
symmetrical,  we  may,  as  in  [3957a],  add  the  two  terms  [3956]  to  those  between  the 
braces  in  [3963].  Hence  it  is  evident,  tliat  if  we  substitute  these  values  of  oe,  5e',  Sy 
[3961,  3962,  3963,  3964/],  in  the  first  member  of  [3957],  liie  result  will  be  equal  to 
the  second  member  of  [3957],  multiplied  by  the  factor  [3964i],  changing  also  the  partial 


f39(;il 


[.3002] 


Tlie  sta- 
hility  of 
the  orbit  of 
a  planet  19 
not  (lis- 
lurbed  by 

[3904] 

lerrns  of 
the  order 
of  the 

[30tJ4'] 

ptjuare  of 
the  dis- 
turbing 
forcen. 


[39<34a] 

[39046] 

[.39G4c] 
[39(>4(/] 

[3964e] 
[:39C4/] 
[3964g:] 


1-28  PERTURBATIONS  OF  THE  PLANETS,  [Mtc.  Cél. 

The   determination  of  the  invariable  plane,    given  in  ^62,   Book  II,  is 
founded  on  the  three  equations,* 

[3965]  c  =m  \/a.{l-t^)  •  COS.  (p  +  m'  ^f77(l^^'2)  .  cos.  y'  +  &c.  ; 

[3965']  c'  =  m  i/a  ."(1— e^)  •  sin.  (? .  COS.  â  -j-  ?/«'  y/«'.(i  — e'"-^) .  sin.  <?'.  cos.  o'  +  &c.  ; 

[3963"]  c"=  7rt \/aT{l^^)  .  sin.  (? .  sin.  ô  +  m' \/«'.(l— e''-^) .  sin.  a',  sin.  ;)'  +  &c.  ; 

«   and   a'  being  constant,   having  regard  even  to   the  terms   [3906' — 3907], 
[3965'"]     depending    on    the    square    of    the    disturbing    force.       The    first    of    these 
equations  gives,  by  neglecting  the  products  of  four  dimensions  in  e,  e',  &c., 
W,    ({>',    &c.,t 

[3966]  constant  =  (  c"  +  if"  )  .  hj  \/rt  +  (  e'  -  +  o'  -  )  .  m'  \/a'  +  &c.  ; 

and  we  have  just  seen,  in   [3964'],  that  the  terms  depending  on  the  square 
[3966]      of  the  disturbing  force,  do  not-  affect  the  accuracy  of  this  equation.      The 

[3964/i]  differentials,  as  in  [3964f].  Now  the  third  and  fourth  lines  of  the  terms  between  the 
braces,  in  the  second  member  of  [3957],  remain  unchanged  [3964(/]  ;  they  must  therefore 
vanish,  as  in    [39605],    by  the  substitution   of  the   expressions    [3959,  3959'J.      In  hke 

[3964il  manner,  the  first  and  second  lines  vanish,  as  in  [3960a],  by  the  substitution  of  the  two 
equations  found  in  [3964e],  corresponding  to  [3958,  3958'].  Hence  the  second  member 
wholly   vanishes,    and    the    result   becomes    as    in    [3964].      We   may   remark,    that   this 

[3964/t]  demonstration  is  restricted  to  terms  having  the  small  divisor  (5n' — 2rt);  but  it  is 
extended  to  other  terms  in  [5935,  Sic.]. 

*  (2497)     Substituting      (  1 -f- tang.-.p)~' =cos.  9  ;     (  1 -)- la'ig-^  <?')~*=^  cos.  p',     &c. 
[3965a.]      j^  [1151],  it  becomes  as  in   [3965].      Making  the  same  substitutions  in  d ,  d'  [1158,1159], 
and  putting  also,  as  in   [1156], 

?; .  cos.ffl  =  sin.  9  .  sin.  ^  ;      (jr.  cos.  (p=  sin.  9.  cos. ^  ;     y. cos. 9':^  sin. 9'.  sin. d',    &jc., 

we  get  [3965',  3965"]  It  may  be  remarked,  that  the  quantities  c',  c",  are  in  the  original 
work  called  c",  c',  respectively  ;  tliey  are  here  altered  so  as  to  conform  to  the  notation 
in  [1158,  1159]. 

t  (2498)    If  we  neglect  terms  of  the  order    t"*,   ©'',   we  shall  have 
[3966a]  /a.(i_e2)  =  (l  — ie2)./«,  cos.(p=l  — Iv^     [44]   Int.  ; 

hence  m  \/a .  (1— e^j  .  cos.  o  ==  m  \/a  —  J  .  («^ -(- 9-)  .  ?«  \/o  ;  substituting  this  and  the 
similar  terms  of    a',    c',    9',    Sic,  in  [3965],  it  becomes 

[39666]  c  =  m  /«  -f-  ?«'/«'  +  &.C.  —  I  .\{t^-\-  (f)  .m\/a-\-  (c'^  +  9'^) .  m'  \/a'  -f-  &:c.|. 

Multiplying  this  by  — 2,  and  transposing  the  constant  terms  — 2m\/a,  — 2in'\/a' — &«;. 
to  the  first  member,  we  get  [3966]. 


[39656] 
[3965c] 


VI  ii.  À  16.j   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        129 

equation    [3965"]  gives,    by  neglecting    the    products    of   three    dimensions 
in    c,  e',   &;c.,    (.?,  ?',   &.c.,* 

6.(3.  sin.  (1)  .  m  v/fl  +  6 .  (.;'.  sin.  c')  .  m\/a'  +  &c.  =  0.  [3967] 

Now  if  we  notice  only  the   terms  depending  on  the  square  of  the  disturbing      [3967'] 
force  [3931 — 3936], f  this  equation  will  hold  good  ;    therefore  the  expression 

f"=  7)1  ^/^(i^.2)  .  sin.  V    sin.  <-'  +  m' \/a'.{[^^^)  .  sin.  ç.  sin.  l,'  +  &e.  [3961:'] 

[3965"],  ^vill   not   be  affected   by  these   terms.       In  like    manner,  we   find,      [3968] 
that  a  similar  result  is  obtained  from  the  equation  [3965'], 

c'=  m  y/a7(l— 6^)  .  sin.  o  .  cos.  J  +  m'/a'.(l— e'^) .  sin.  ©'.  cos.  è'  -f  &c.  [3969] 

Hence    the    invariable    plane,    determined    in    §  62,    of   the   second    book     [3969'] 
[1162,    1162'],    remains    unchanged,    even    when    toe    notice    these    terms 
depending  on  the  square  of  the  disturbing  force. 

16.     The  terms  depending  on  the  square  of  the  disturbing  force,  have  a 
sensible  influence  on  the  two  great  inequalities  of  Jupiter  and  Saturn  ;  t    we     [3969"] 


*  (2499)    Neglecting  terms  of  tlie  order  y^  ^'^  we  may  put    siii.(p=(p;   sin.o'=:(p',  &c. 
[4.3]  Int.      If  we  also  neglect  terms  of  tlie  order    e^?,  e'^ç)',    &c.,  the  equation  [3965"] 
may  be  put  under  the  form       c"=:  (  9  .  sin.  6)  .  m  s/ a  -\-  (  ç'.  sin.  a')  .  ni'  \/a'  -\-  &c.  ;       and      [3967a] 
if  we  take  the  variation  relatively  to  the  characteristic  (3,  it  becomes  as  in  [3967]. 

t  (2500)    The  terms  here  referred  to,  are  those  mentioned  in  [3943'],  and  computed 

for  two  planets  in  [3929— 393-3'].      The  equations  [3930,  3930']  may  be  put  under  the     [3968a] 

following  forms, 

0.(9.  sin.  é)  .m  s/ a  -f-  ^  •  (  ç'.  sin.  ^  )  .  m'  i/(/'^  0  ; 

[39686] 
0  .((p  .cos. é)  .m\/a  -f- 0" .  (ç'.  cos.  H)  .m'^a=^0. 

In  the   same  manner,  other  planets  produce  similar  expressions,  and  the  sum  of  all  the 
equations,  corresponding  to  the  first,  forms  the  equation  [3967]  ;  a  similar  equation  may     [3968c] 
also  be  obtained  from  the  sum  of  the  equations  of  the  second  form. 

%  (2501)    Substituting  the  expressions  [37566,  c,  e],   in    SR    [3764],  it  becomes  as 
in  [3970J  ;  observing,  that  the  coefficients  of    h^  +  P,     h'^+l'^    [3764],    are  equal  to     [3969a] 
each  other,  as  appears  by  multiplying  [3752i]  by    —  4. 

VOL.  III.  S3 


130  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Ctl. 

shall  proceed  to  determine  the  most  considerable  of  these  terms.      We  have 
seen,  in  [3764],  that  the  expression  of    R    or    iR    contains  the  function 

<«=  -^.(.H.-).i2„.(^)+„..(''-:)( 

,™,  +.'.....os.(.-.).|4.».+.„.(:^)  +  2..('->„..(^) 

[3970]  ^f  ^^'*^  increase  the  quantities  e,  fi',  w,  ra',  r,  in  this  expression,  by  their 
variations,  depending  on  the  angle  b  n  t  —  2nt,*  we  shall  obtain  in  R 
some  terms  depending  on  the  same  angle  ;  and  it  would  seem,  on  account 
of  the  divisor  on' — 2n,  connected  with  these  variations,  that  these 
terms  mioht   become   sensible.       But  we  must   observe,    that    this   divisor 

[3970"]  disappears  in  d  R,  because  the  differential  characteristic  d,  refers  only 
to  the  co-ordinates  of  m,  or  to  the  variations  of  e,  ^  [916']  ;  so  that  it 
introduces  the  multiplicator    on'  —  2  n.      Now  we  have  seen,  that  the  great 

[3970'"]  inequality  of  m  depends  chiefly  on  the  term  3  affn  dt .  dR  [1070"]. 
The  inecjualities  of  the  radius  vector  and  the  longitude,  Avhich  depend  on 
the  variations  of    the    exccntricities   and   perihelion,    relative    to    the   angle 

[3971]  5 n't — 27it,  have  therefore  very  little  influence  on  the  two  great  inequalities 
of  Jupiter  and  Saturn. 

We   shall   see  hereafter  [4392,  &c.,  4466,  &c.],   that  the  most  sensible 
inequalities   of  these   two   planets,  depending   on  the   simple   exccntricities 


*  (2502)    The  variation    of    c,    «',    ■ro,    8ic.,    here    referred    to,    are    tliose   represented 

ro970a]     '^y    ^  ^'    '^*''    ''^'    ^''"    [3907 J,  c,  c/]  ;  all  of  which  have  the  divisor    5  «'  —  2  îi  [3907«]  ; 

but  the  divisor  is  destroyed  in  finding  their  differentials    (/  e,    d  -a,    Stc,  as  is  evident  from 

[3908c,  &ic.].      Hence   it  follows,    that    the   differential   of  the  expression    [3970]   gives, 

[39704]     in     d  H  R     or      d  R,     terms   depending  on     ede,    e  e'  d  w,    &c.,     wliich  do  not  contain 

this  divisor  ;  and  if  we  substitute  them  in  the  chief  term  of  the  great  inequality  [3970'"], 

they  will  produce  terms  which  are  of  the  order    ?h'^.    or  of  the  order    m',    in  comparison 

[3970c]     with  the  chief  terms  computed  in  [3844,  4418,  4474]  ;  but  as  these  terms  of  the  order  w'^, 

[3970(i]    have  the  same   divisor      (5  n  —  2  ?i)^,      a*   the   chief  terra,  it  seems  proper  to  examine 

carefully  into  their  exact  values,  instead  of  neglecting  them,  as  the  author  has  done.      We 

shall  also  see,  in  [4006^,  &ic.,  4431/"],  that  several  terms,  omitted  by  the  author,  similar 
[39/ Oc]  ■-  .  .  -11  -1 

to  those  treated  of  in  this  article,  are  quite  as  important  as  those  which  he  has  retauied. 


VI.  il.  §  16.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         131 
of  the  orbits,   are  relative   to  the  angle    nt  —  2  n't.       We  shall  put* 

-=  F.  COS.  (7ii  —  2n't  +  s  —  2i'  +  A),  [397^] 


-5, 
a 


5r 
for  the  term  of    —  ,     depending  on  this  angle  ;  and 

6v  :=E.sm.  (nt  —  2n't-\-s  —  2s'-JrB),  [3973] 

lor    the     term    of     6  v ,      depending    on    the    same    angle  ;     also    for    the 
correspondmg  terms  oi      -7-     and     &  v , 

^  =  F'.  COS.  (nt  —  2tt't  +  s  —  2s'  +  A');  [3974] 

ôv'  =  E'.sm.(nt—2n't  +  s  —  2s'-^B').  [3^4'] 

If  we   suppose   that    R    corresponds  to   Saturn,   disturbed  bij  Jupiter,    and     [3974"] 
then  develop  it  relatively  to  the  squares  and  products  of  the  excentricities 
and  inclinations  of  the  orbits,  noticing  only  the  angle    Sn'  t  —  n  t,     we  shall    [3074'"] 
obtain,  as  in  [3745,  Stc],  a  function  of  this  form,t 

R  =      il/(»'.  é~ .  cos.  {Qn't  —  nt  +  3^'  —  i  —  2  z-I) 

+  il/fi' .  e e'.  cos.  (3n'i  —  M  i  +  3  i'  —  s  —  ^  —  ^') 

+  M^-Ke'.  cos.  (3m'<  — n  ^  +  3;'  — 5  — 2«) 

+  M'^'.7=.  cos.  {Sn't  —  nt  +  Qi'—s  —  2n). 


*  (2503)    The  terms  of    5«    [4392],  depending  on  the  angle     nt  —  2  n't,     or  rather 
on     2»i''i  —  71'^/,     are  of  the  order  136'  or  56',  and  may  be  reduced  to  the  form  [3973];      [.3973a] 
those  of  0  v'  [4466]  are  of  the  order  182%  417%  and  may  be  reduced  to  the  form  [3974']  ; 
they  are  the  largest  terms  of  the  expressions  [4392,  4666].      In  like  manner,  tlie   parts 

of     —,    4    [4393,  4467],    may   be   reduced    to    the   forms  [3972,  3974];    the  last  of     [.3973i] 

"  CI 

which  is  the  greatest  term  of  [4467] . 

t  (2504)    This  value  of    R    is  similar   to  that  assumed  in  [3745 — 3745'"],  changing 
reciprocally  the  elements  of    m'    into  those  of    m  ;    also    M'--'>  into  M'-°\  M^"^  into  M^-'' ;     [3975a] 
and  afterwards  putting    i  =  — 1.      This  form  of  the  angles  in  the  value  of  R,    is  selected 
because  it  produces,  in  connexion  with  the  variations  [3972—3974'],  terms  in    dR,    d' R,      [39756] 
of  the  order   m^,   depending  on  the  same  angle    5  n't  —  2  n  t,    as  the  great  inequality,  as  is 
seen,  in  [3979,  3982,  3985, 3989,  3991].      We  may  remark  incidentally,  that  in  this  article 


[3975] 


132 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


[3976]  The  quantity  3I^''\  e'".  cos.  [3  n't  —  ?i<  +  3s'  —  s  —  2y>')  arises  from  the 
development  of  the  term  of  R,  denoted  by  yi'''.  cos.  («'  —  v)  ;*  in  which 
we  must  increase  ?•  by  S  r,  r'  by  i  r',  v  by  6v,  v'  by  i  v'.  This 
is  the  same  as  to  increase,  in  the  development  of  this  term,  a  by  or. 
a  by  6  /■',  and  n  t  —  nt  by  &v'  —  -5 1;  ;  by  which  means  it  produces  the 
following  expression,! 

iJ  =  _  3/(»).  e'=.  {iv'  —  i  v)  .  sin.  (3  m'  ^  —  n  i  +  3  /  —  J  —  2  ^') 


[3976'] 


[39' 


[3978] 


+  a.  (—,--)  .  e'-.  ~  .  COS.  (3n't—7it  +  3^:'—s  —  2zi') 


d  a 


a 


+  a'.  (^^^  .e'-.~.  COS.  (3n/t  —  nt+3/—s  —  2 ^'). 
\    da     J  a 


[3975c] 
[3975rf] 

[3975e] 


[3976a] 
[3976t] 


the  values  B,  i?, ,  difler  from  those  in  other  parts  of  the  work  ;  since  B,  B,  [3974",  4005'] 
take  the  place  of  jf?',  B  [1199'],  respectively;  m  being  the  mass  of  Jupiter,  »«'  that 
of  Saturn.  The  object  of  the  author,  in  making  this  change  in  the  value  of  B,  is  to 
obtain  express  formulas  for  the  direct  computation  of  the  inequalities  of  Saturn,  which  are 
much  larger  than  those  of  Jupiter  ;  and  then  to  deduce  the  corresponding  smaller  ones 
of  Jupiter,  by  means  of  the  formula  [1208]  ;  it  being  evident,  that  this  method  of 
deduction,  in  the  cases  where  it  can  be  applied,  must  be  more  accurate  in  finding  the  small 
inequalities  of  Jupiter  from  the  large  ones  of  Saturn,  than  in  an  inverse  process. 

*  (2505)  The  part  of  B,  independent  of  j'^,  corresponding  to  the  action  of  Jupiter 
iipon  Saturn,  is  found  by  changing,  in  [3742],  ?»',  r,  r',  v,  v',  into  m,  r .  r,  v',  v, 
respectively  ;  and  if  we  suppose,  that  when  a,  a,  nt  -\-  s,  ii  t  -\-  s',  are  changed 
into  r,  r,  v',  v,  respectively,  the  quantity  .4'''  [3743]  becomes  .^/'',  we  shall  get, 
from  [3742,  3743],  for  this  part  of  B,  the  following  expression, 


:-  .  5; .  .^/''.  cos.  ?" .  («' — i;). 


[3976c]        jR  =  — .cos.  («' — v)  —  ■   ,,  o — h — ; 7~~i rT~^^w'' 

'■  ,.a  \  ''        v/i'  — 2rr.cos.[v  —  «)  +  ?    jj 

Substituting  in  this  the  values  of   r,  r',  v,  v'  [952,  953],  we  obtain  an  expression  of  B, 
[.3976(/]    of  the  same   form  as  [957],    and    possessing  the  properties    mentioned    in    [957 — 963]  ; 
moreover,  the  term  multiplied  by  the  factor    e'^,    being  represented  by 

[3976c]  M^''\e'^.cos.  \i .  {71'  t  —  nt  -^  s'  —  i)  +  2n'  t  -{-  2s'  —  2  z:'}      [9.57—959'], 

becomes  of  the  form  [3976],  by  putting  i=l  ;  then  the  corresponding  term  of  B  [3976r] 
is  of  the  same  form  as  in  [3976']. 

t  (2506)     The  term    Jf '"'.  c'^.  cos.  (3  ?i'/— ?i  <  +  3  s'— £— 2  to')    [3975],  is  produced 

in  the  function    B,   by  a  development  similar  to  that  which  is  used  in  [957],  that  is,  by 

[3977a]     the  substitution  of  the  cV/p^icoZ  values  of   u^,    v,,    &c.,  without  noticing  the  perturbations 

[3972 — 3974'].      If  we  wish  also  to  notice  these  terms,  we  may  suppose    a,  a',  v,  v',    to  be 


VI.ii.^16.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         \S3 

This  produces  in    R,    the  terms* 

R^—i,  il/"".  E'.  e'-.  COS.  (  5  »'  /  —  2  n  ^  -f  5  /—  2  .■  —  2  ^'—  B') 

+  h  M"".  E  .  e'-.  COS.  (5n't  —  2nf  +  5s'—2i  —  2^'  —  B) 

[3979] 

+  1  a' .  (^^].  F'.  e\  COS.  (5  I,.'  t-~2nt  +  o^'—2i-^2^'—A') 
\  a  a    J 

+  1  a  .  ('^'*^)  .  F.  e'\  COS.  (5  n'  ï  —  2  «  «  +  5 .-'—  2  -=  —  2  ^'  — ^  ). 


increased,  respectively,    by     Sr,    (ir,    5v,  5 v' ;      liy   which    means      A'Kcos.i.{v' — r)     [SQ^ya'] 
will  be  augmented  by  the  three  terms  in  the  second  member  of  the  following  expression,  in 
which  we  have  retained  the  factor  i=l,   for  the  purpose  of  more  easy  derivation  hereafter; 


[39776] 


/>.\A''\ cos. i.{v' — v)]  =  —  A''\  i  .{Sv'—5v).  sin.  i  .  (  v'~v) 

and  in  the  same  manner  as  we  have  derived  from     .^''^  cos.  i  .{v' —  v)     the  term 

.¥<">.  f'^  cos.  \i .  {n  t  —  nt  -\'  s  —  s)  -i^  2  n'  t  -\-  2  s'—2tz']  [3976e],  [.3977f] 

we  may  derive  the  three  terms  [.3978]   from  those  in  [39776].      Thus  the  first  term  of  the 
second  member  of  [39776]  is  the  variation  of    ^'\cos.i.{v'  —  v)    or  of    J">.cos.(t)' — v),     [3977rf] 
supposing  the  angle     i  .  {v  —  u)     to  increase  by     i.((5j)' — àv);      in  like  manner,  the 
first  line  of  [3978]  is  the  variation  of  the  term 

iH'"'.  e'2.  COS.  \i  .  {n't  —  nt  +  i' —  e)  -f  2  u'<  +  2  e'—  2  zi'],  [3977e] 

supposing  the  angle     i  .{n't  —  nt  -\-  s  —  s  ) ,     corresponding  to     i  .  {v'  —  v),     to  increase 

by  the  same  quantity     6  v' —  5  v  .      The  second  line  of  [3978]  is  deduced  from  the  second     [.3977e'] 

term  in  the  second  member  of  [39776],  by  supposing    a   to  be  increased  by    S  r   in  ^'" 

and    .W".      Lastly,  the  third  line  of  [3978]  is  derived  from  the  third  term  of  the  second     [3977/] 

member  of  [39776],  by  supposing    a    to  be  increased  by    5  r ,    in    ^"'  and  JW'"'. 

*  (2507)  The  expression  [3979]  is  deduced  from  [3978]  by  the  substitution  of 
[3972 — 3974],  and  reducing  by  [17 — 20]  Int.,  retaining  only  the  angles  which  are  similar 
to  that  of  the  great  inequality,  depending  on 

bn't  —  2nt  =  {Zn't—nt)  —  {nt  —  '2n't)  ;  [39796] 

or  the  difference  between  the  angles  contained  in  [3978]  and  those  in  [3972 — 3974']. 
VOL.  in.  34 


134  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

^^-  We  shall  pxit  à' R  for  the  differential  of  R,  supposing  the  co-ordinates 
of  m'  to  be  the  only  variable  quantities.  In  the  terms  multiplied  by  E' 
[3981]  and  F',  the  part  5  7i't  —  ni,  of  the  angle  5  n'i  —  2n/,*  is  relative  to 
these  co-ordinates.  In  the  terms  multiplied  by  E  and  F,  the  part  3  n  t^ 
of  the  same  angle  5  n't  —  2nt,  is  relative  to  the  same  co-ordinates; 
therefore  we  shall  have,  by  noticing  only  the  preceding  terms  of  R  [3979], 

rt'd'i?z=       i.{5n'  —  n).di.a'M(°KE'.e'^.sm.{5n't  —  2nt-{-às'  —  2;  —  2m'  —  B') 


[3982] 


[3983] 


—  i.(5?i'  — ?0-'/^.«'^-(^^)-F'.e'2.sin.(5n'<— 2»(«  +  5.='— 2.-— 2^'— ./î') 

—  ^.n'dt.a'J\I'°\E.e'^.sm.{5n't~2nt-{-5s'  —  2e  —  2zi'  —  B) 

—  ^  .n'tl  (  .aa'.  (■^~-\ .  F.e'^.sm.{5  n'  t  —  2nt  +  5  !  —2s  —2-:^'  —  A). 

The     term  ilf  ".  e  e'.  cos.  (3  ?i'ï  —  n  ï  +  3 /— .=  — ^  —  ^')  [3975], 

results  from  the  development  of     A'^-\  cos.  2  .  (v' — v),     in  the  expression 


*  (2508)     The  difterential   relative  to    d'    [-3980],    does  not   affect    nt    in  the  angle 

[.3989«]      3ii'f  —  nt,     which  occurs  explicitly  in  [3975],  so  that     d'.{3n't  —  nl)  =  3  7i'cl t  ;     but 

6  v' 
[39836]     this  cliaracterlstic   d'  affects  the  w/io/e  of  the  values  of    —,    i5d'   [3974,3974'],  connected 

with  F',  E',  consequently  the  whole  of  the  angle  nt  —  2  7i't,  which  occurs  in  these 
values,  must  be  considered  as  variable,  and  its  differential  is  n  (t  i  —  2n'dt.  The 
difference  of  these  two  expressions  gives 


[393'25'] 


[3982f]  à'.{ron't  —  2nl)=à'.[3n'l—n()  —  à'.{nt  —  2n'i)  =  {5n'—n).dt; 

which  must  be  taken  for  the  differential  of  tlie  angle     b  n' t  —  2nt    [3979J],  depending 

on  E',  F',  in  the  first  and  third  lines  of  [3979]  ;    hence  we  obtain  the  first  and  second 

(3982(/]     lines  of   [3932].      In   like  manner,    the   differential    relative   to    d'    does  not   affect   the 

[398ae]     expressions  of     —,    Sv    [3972,  3973],   connected   with  the  factors    F,   E  ;    or  in   other 

words,  the  differential  of  the  angle  nt  — 2n'  t,  connected  with  these  factors,  must  vanish  : 
and  we  shall  have  A'.{nt  —  2?i'<)=0;  subtracting  this  from  [3932a],  we  get,  in 
this  case,  for  the  differential  of  [3979i], 

[398%]  d'.  (5  7!'<  — 2h<)  =d'.  (3?i'<— M^— d'.  (?i  t —  2^^  t)=3  n' dt . 

Substituting  this  in  the  differential  of  the  second   and    fourtli   lines  of  [39791,    we  get, 
[3983/!]  ^  L  J'  6     ' 

respectively,  the  third  and  fourth  lines  of  [3982]. 


[39841 


[3985] 


VI.  ii.  ^  16.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         135 

of    R*      Therefore  we  must  vary,  in  this  term,     a    by    ir,     a'    by    ir',         ^^ 
also     2 n't  —  2nt     by    26v'  —  2iv;     and   by  this  means  we  obtain  the 
following  terms  of  R, 

R  =  —2  M^'\  e  e'.  (d  v'  —  6v).  sin.  (3n' t  — ti  t  +  3e —s  —  z^  —  zi') 

+  a.    )  .  ee.  —  .  cos.  (3n  r  —  nt  +  3e'  —  s  —  ra  — ra') 

\   d  a    J  a 

+  a'.  f^^!L_)  .ee'.^.cos.  (3  n'/ —  n  r  +  3e'  — s  — ^  — ^'). 
\    an     y  a 

Hence  the  part  of     a'd'R,     relative  to  this  expression,  is 

a'à'R=       {5n'—n).dt.a'J\P^\E'.cc'.sm.{5n't—2nt-lr5s—2s  —  7Z—zi'  —  B') 

—  i.{57i'  —  n).dt.a'-^.('^-^^\F'.ee'.sm.{5n't  —  '2nt  +  bs-22—z^-zs'-A') 

—  37idt  .a'  M^'lE  .ce'.sm.{5n'  t  —  2nt-j-5i'  —  2i  —  ^—^' —B) 

—  in'dt.aa'.(^-^^\F.ee'.sm.{57i't  —  2nt  +  5s'  —  2s—z!—'u/—A). 

The    term        M<^>.  e".  cos.  (3  n' t  —  nt  +  3^— ^ —  2^)       [3975],    arises      [.3986] 
from    the    development    of       J'^'.  cos.  (3  y'  —  3i'),        in    the    expression 

*  (2509)  Proceeding  witli  the  term  depending  on  M^^K  [3975],  in  the  same  manner 
as  we  have  done  with  that  multiphed  by  AI"^\  in  tlie  tliree  preceding  notes,  we  find,  that 
it  may  be  put  under  the  form 

M^'Kee.cos.\i.  {n' t  —  n  t -^  s  —  s)  -J^- ,1' t -j- n  t -j- s" -{- e  — -ui' —  tz],  [3984a] 

supposing    i  =  2  ;    by  whicli  means  it  becomes  as  in  the  second  Une  of  [3975],  and  tlie 
corresponding  term  of  [39~6c],  is  of  the  form 

à?ft.^/*^.  cos.  t .  {v'—  v)~A'''''.cos.2  .  {v'—v).  [.39844] 

The  variations  of  this  term,  depending  on     or,  fir',  ou,  f5  «',  are  as  in  [3977è],  supposing 

i  =  2;     and  from  these  we  may  deduce  the   functions  [3984,  3985],  by  a  computation 

similar   to   that   used   in    finding    [3978,  3982].       We  may,  however,  obtain  the  former 

by  derivation  in  a   more    simple   manner;    for   if  we   change    M''^\    c'^,    — 2 -a',    into      rr^,.u. 

M'",    ee,   — «  —  to',     respectively,  we  shall  find,  that  the  first  term  of  [-3975]  becomes 

like  the  second  ;  and   the  doubling  the  values  of   '5  v',  &  v,  in  [.397761,  on  account  of  the 

^  '        '        L  J'  [3984rfl 

factor  r  =  2,   make  it  necessary  that  we  should  double  the  values  of  E,  E'  [3973,3974']. 

Making  these  changes  in  [3978,  3982],  they  become,  respectively,  as  in  [3984,  3985). 


136  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

of  R*      Therefore  we  must  vary,  in  this  term,    a   by   6 r,    a'   by    6 r',    and 

13987]      3n't  —  3nt     by     Sôv' —  3iv  ;      hence  we  get  the  following  terms  of  B. 

R  =  —  3  M''~\  e\  (ôv'  —  iv)  .  sïn.  (3  n'  t  —  n  t  +  3  s'—s  —  2zs) 
[3988]  +  a  .  f'^^\  .  e".  -  .  COS.  (3n't  —  nt  +  3s'  —  s  —  2^) 

\   d  a     J  a 

+  «'.  y^^)  •  è\  ~  .  COS.  (3n'i  —  n  ï  +  3  -='  — s  —  2^). 

Therefore  the  part  of    a'  d'R,    relative  to  this  expression,  is 

a'à'R=       §.{5n'—ii).cIt.aM^-^''.E'.e^.sm.{5n't—2nt  +  5s'  —  2e—2vs  —  B') 

—  i.{5n'— n). dt.a"^.(-^^^].F'. e^.sm.  {5  n't  — 2nt  +  5  s'— 2  s  — 2zi  — A') 
L3989]                      —^.n'dt.a'J\'r-\E.e''.sm.{rj7i't  —  2nt  +  5s'—2e—2z^—B) 

—  %.n'dt.aa'.f-^\F.e''.sm.(5n't  —  2nt-{-5s'—2i—2z^—A). 

[3989']     Lastly,    the    term       M'=' .  -/.  cos.  (3n' t  — 7it  +  3  s' —  s  —  2n)       [3976], 
[3989"]     arises  from  the  term  multiplied  by  -/.cos. (3r' — v),    in  the  expression  of  i2;t 


*  (2510)    Proceeding  as  in   the  last  note,  we   may  put    the  term  [.3975],   depending 
on  M'-'^-,  under  the  form 

^3988o]  M<^\  e^.  cos.  \i  .  {n'  <  —  n  Ï  +  s'—  s)  +  2  n  <  +  2  e—  2  ^f , 

supposing     i  =  3  ;     and  then  the  corresponding  term  of  [3976f]  is  of  the  form 

pjjjggj,  i  to'.  A}'K  cos.  i  .  {v  —  v)  =  A^^'.  cos.  3  .{v'—v). 

The  variations  of  this  term  are  as  in  [3977 J],  supposing  i  =  3;  from  which  we  may 
get  [3988,  3989],  in  the  same  manner  as  [3978,  3982]  were  found.  The  same  result 
may  be  obtained  more  easily  by  derivation,  as  in  the  last  note  ;  by  changing,  in  [3975,  &,c.], 

[3988c]  M^"',  e'^,  A'-'\  2zi',  into  M'-'',  e^,  A'-^\  2  s,  respectively;  by  which  means  the  first 
term  of  [3975],  changes  into  the  third;   and  tlie   trebling  of  the  values  of    ôv',  ôv,    in 

[3988(n  [3977i],  on  account  of  the  factor  /:=:3,  makes  it  necessary  to  change  E,  E' 
[3973,3974']  into  3E,  3  E',  respectively.  Making  these  changes  in  [3978,3982], 
they  become  as  in  [3988,  3989],  respectively. 

f  (2511)    We  must  now  compute  the  terms  arising  from  the  introduction  of  the  increments 

[3990a]     i5  r,    Si-',    &v,   5v',    in  the  expressions  of  J-,  r',  v,  v ,   connected  with  the   factor   7®,   in 

the  value  of  R  [3742]  ;  which  were  neglected  in  [3976«].      These  terms  of  R  may  be 


VI.  il.  §  16.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        137 


we    must    therefore    vary     a    by    6r,     a'    by    àr',     S  n't    by    Siv',      and 
n  t    bv    à  V  ;     hence  we  obtain  the  following  terms, 

R  =.  —  M<''.  y^.(3ôv'—&v).  sin.  (Sti't  —  nt-\-3/  —  s  —  2u) 

+  a  .  ('^_:^\  .   "-,  iZ'.  COS.  (3n't  —  n  t  +  3  /—  e  — 2  n) 
\  da    J  a 

+  «'.  (  ^/V)./'.  4-cos.('3n'«  — n<  +  3/  — E  — 2n). 
\  (I  a    J  a  ^ 


[3990] 


deduced  from  those  depending  on  y^,  in  [3742],  by  changing  the  elements  as  in  [3976r(]. 
These  four  terms  of  R  [3742]  are  ah'eady  muUiphed  by  the  factor  y^,  of  the  second 
dimension,  and  as  none  of  a  higher  order  are  noticed  in  [397.5],  we  may  substitute  in 
these  terms,  r=a,  r' =  a' ,  v  ^=nt  -{-  b — n,  v'=n(-\-s'  —  IT;  and  retain  only 
angles  of  the  form  3n'<  —  nt,  assumed  in  [3975].  Now  it  is  evident,  that  the  two 
first  of  these  terms  of  R  [3742],  depending  on  the  angles  cos.  (i;'  —  v),  cos.  {v' -\- v), 
produce  the  angles  n't  —  nt,  n't-\-nt,  which  are  not  included  in  the  proposed  form. 
The  third  of  these  terms  [3742]  contains  v'  —  v  in  its  numerator  and  denominator, 
and  when  the  denominator  is  developed,  as  in  [3744],  the  whole  term  will  depend  on 
quantities  of  the  form  cos.  ?*.(«' — v)  or  cos.  i.(n'^  —  nt),  which  are  not  comprised 
in  the  form  ^n!t — nt,  now  under  consideration  ;  so  that  we  need  only  retain  the  last 
term  of  [3742],  which,  by  making  the  changes  indicated  in  [3976a],  may  be  put  under 

Ttt  'V  T  T    COS  I  y'  ~l~  v  ^ 

the  form         R  = {-  . '- ' j.       Now  if  in  the  formula  [3744], 

4       {,-2  — 2 rr'. COS.  (w'—î))+»-'2 1 ^ 

we  change     a,    a',    nt-\-s,    n't-\-s',    B'-'\     into     r,    r,    v,    v',    J5/",     we  shall  get 


[3990i] 
[3!)90c] 
[3990</] 

[3990(/'] 


\r^—  2rr'.  cos.  {v'—  v  )  -f  r'~l      ^  =  ^S.  5».  cos.  i .  (  v'—v). 

Substituting  this  in  R  [3990e],  and  reducing  by  means  of  formula  [3749],  it  becomes 

iî  =  —  :i m  .  f.  r  r.  *  2  .  B'p.  cos.  \i  .  (v'—v)  -f  «'  +  jj j. 

If  we  change    î    into    i — 1,    and  put      — |- ?«  .  r  r*.  i?/'-"  =  JW''',      we  get 

R  =  f.S.M'-'^.cos.  {i.{v'—v)'}-2v]; 

which  in  the  case  of  i^3,  produces  a  term  of  the  form  R  =  M'-^\'^^.  cos.  {3  v' — v). 
Taking  the  variations  of  this  term,  as  in  [3977a',  &c.],  we  get  the  following  expression, 
similar  to  [3977è], 

&.{M'^\f.cQs.{Sv'-v)  \  =  —.¥"1.^2.  {3Sv'—  S  «)  .sin.  (3  v'—v) 


[3990/] 

[3990/'] 

[3990g-] 
[3f>90A] 

[3990i] 


Substituting  in  this  the  values  [3990è],  we  obtain  [3990]. 
VOL.  III.  35 


[3991] 


138  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

Hence  we  obtain  in     a' d' R,     the  following  terms,* 

aà'R=      ^.{5n~7i).dt.a'M'-^\E'.f.sm.{5n't  — 27^-^-5;'— 2!  — ^n  —  B') 

—  i.{5n'—n).dt.a'~.  [~j^)  F'.  f.  sin.  (5  n't  —  2n  t  +  5  s'— 2  s  — 2  n— ^') 

—  ^n'dt.  a'M^^'lE.  f.  sin.  (5  wV  —  2  ?i  ^  +  5  s'  —  2  s  —  2  n—B) 

—  ^n'di.aa'.l  -j^j  ■  F.f. sm.  {5n't —  2  nt -{-5i'— 2c  — 2  n—^). 

The  most  sensible  inequalities,  arising  from  the  squares  and  products  of  the 

[3991]     excentricities  and  inclinations  of  the  orbits,  which  neither  have     5  n' —  2  nf 

for  a  divisor,  nor  depend  upon  the  variations  of  the  elements  relative  io  the 


*  (2512)  Tlie  expression  [3991]  is  deduced  from  [3990],  in  the  same  manner  as 
[3982]  is  from   [3978]  ;  or  more  easily  by  tlie  principle  of  derivation.      For  if  we  cliange 

[3991a]  M'^°\  e'2,  5v',  —  2  «',  into  Jl/"\  y^,  Si'iv',  —  2n,  respectively,  the  function 
[3978]  will  become  as  in  [3990]  ;  consequently  E'  [3974']  must  be  changed,  as  in  [3984f/], 

[.39916]  jj^^^^  g^,_  Making  the  same  changes  in  [3982],  which  was  deduced  from  [3978], 
we  get  [3991]. 

t  (2.513)  The  divisors  in  [3714,  3715],  which  may  be  small,  in  the  theory  of  the 
perturbations  of  Jupiter  and  Saturn,  are  i>i'-\-{3  —  i)-n,  in' -{-{I — î).n,  în'-{-[2 — i).n; 
"•^  and  since  n'^fn  nearly  [38 18fZ],  they  become  (3  —  %i)-n,  (1 — f?).H,  (2 — |-î).«. 
If  we  put  /  =  5,  the  first  divisor  becomes  0,  the  others  being  large.  If  i  =  4,  the 
•  last  divisor  becomes  — f  ?i,  and  the  others  are  larger.  If  /  =  3,  the  last  divisor 
becomes  ^  n,  and  the  others  are  greater  then  this  quantity  ;  and  it  is  evident,  that  next 
to  i^5,  this  value  of  i  gives  the  least  value  to  the  divisors  [3992a]  ;  therefore  the  terms 
of  7-0  r,  ÔV  [3714,3715],  of  the  second  order,  relative  to  the  quantities  e,  e',  y,  and 
depending  on  the  angle  3?*'/  —  nt,  maybe  increased  by  this  divisor,  so  as  to  become 
greater  than  other  terms  of  the  same  order,  relative  to  e,  e',  y,  which  have  not  a  small 
divisor.  This  reasoning  is  confirmed  a  posteriori  by  the  inspection  of  the  numerical  values 
of  5r"',  Sr",  Hv",  û  v"  [4397,4470,4394,4468],  in  which  the  terms  depending  on 
the  angle  3  n't  —  n  t,  are  generally  greater  than  any  of  those  that  are  noticed  in  [3991'], 
[.3992^]  excepting  4n't—2nt.  This  last  angle  is  here  neglected,  because  the  terms  or,  ôv,hc., 
depending  upon  it,  do  not  produce  in  [3995],  functions  of  the  form  [3998],  depending 
on  the  angle  5  n'  t  —  2  n  t,  which  are  the  only  ones  under  consideration  at  the  present 
moment.       Now  if  we  notice   only  the  temis  depending  on   the  angle     3  7i't  —  7it,     in 


[39926] 


[3992c] 


or 
[3992c]      [3714,    3715],    we   shall    obtain    for      —,     Sv,     quantities  of  the  forms  [3992,  3993], 

6r' 
and  in  like  manner,  in        —,    Sv',     terms  of  the  forms  [3994,  3994']. 


VI.  il.  §16.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        139 

angle     bn't  —  Int,      are  those  corresponding  to   the  angle      5  n't  —  nt. 
We  shall  put 

—  =  G .  COS.  (3  n'i  —  n  <  +  3  e'—  Î  +  C) ,  [3999] 

(5  r 
for  the  part  of       -,     depending  on  this  angle  ;  also 

ÔV  =  H.  sin.  (3  n't  —  n  t  +  3  s' —  s  +  D),  [3993] 

for  the  part  of     ô  v,     depending  on  the  same  angle  ;    in  like  manner, 

^-4  =^  G'.  COS.  (3  71'  t  —  nt  +  3  i'  —  z  +  C') ,  [3994] 

a  ^ 

Ô v  =  H'.  sin.  (3n't  — nt-ir  3s'— s+D'),  [3994'] 

5  r' 
for  the  parts  of    -7-,    èv',     depending  on  the  same  angle.      The  expression 

of   R,    developed  relative  to  the   first  power  of  the  excentricities,  contains 
the  two  following  terms,* 

R=      iV'O'.e.cos.  (nt  —  2n't  +  s  —  2i'-\-zs) 

[3995] 

+  N^'Ke'.  cos.  (nt  —  2n't  +  e—2s'  +  ^'). 


*  (2514)    In   the    same   manner  as   we   have  deduced,    from    R    [3976c],    the    three 
terms  [3916e,  3984»,  3988a],  of  the  second  order  in   e,  e',   we  may  obtain  two  of  the     [3995a] 
first  order  in    e,  e',   of  the  following  forms, 

R=      :^-i^\e.cos.\i.{nt-nt^e'-s)-{-7it-i-s-z,\  ^^^^^^ 

+  JV('>.e'.cos.  li.(«'<— ?i<4-s'— 6)  +  ?i7  +  e'-ra'}. 

If  we  put     i  =  2,     in  the  first  of  these   terms,  it  becomes  of  the  same  form  as  the  first  [3995c] 

term  of  [3995]  ;  and  by  proceeding  in  like  manner  as  in  note  2506,  we   easily  perceive  [3995(/] 

that  this  term  arises  from  the  development  of    A'-'^^.cos.i  .  {v' — v),     supposing     i  =  2,  [3995e] 
as  in  [3995c].      Moreover  the  second  term  of  R  [3995è],  becomes  of  the  same  form  as 

the  second  term  of  [3995],  by  putting     i=l;     and  then  the  term     Jl'^'\cos.  i  .  {v'—v),  [3995/] 
upon  which  it  depends,  becomes     .a'",  cos.  [v —  v),     as  in  [3998']. 

We  have  already  computed,  in  the  case  of    i  =  2,     the  effect  of  the  substitution  of  the 
variations    5r,    or',    ôv,   Sv',    in  the  development  of    .^^-'.cos.  2.  (  y' — v)  [3984i],    and     [3995g-] 
we  have  found  that  this  substitution,  in  [3984i(»],  produces  the  function  [3984].      A  similar 
method  may  be  followed  with  the  first  line  of  R  [39956]  ;  but  it  is  more  simple  to  derive     ^         ' 
it  from    [3984a,  3984].      This  is  done  by  changing,  in  [3984a],   the  factor     M^^Kee' 
into     JVC",  e,     and  decreasing  the  angle,  which  is  contained  under  the  sign  cos.,  by  the      [3995i] 


[3996] 


[3997] 


140  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[3995']  The  first  of  these  terms  arises  from  the  development  of  J'^.cos.  (2«' — 2v), 
in  the  expression  of  R  ;  and  in  this  development  we  must  increase  a  hy  6r, 

[3995"]  a'  by  or',  2  n't  —  2nt  by  2ôv' — 26v;  from  which  we  obtain  the 
following  expression, 

R=      2  iV'"'.  e  .  (6  v'—  &v).  sin.  (^nt  —  2n!t  +  s  —  2i'-\--:z) 

+  a.  (~ — )  .e.—  .COS.  (îit  —  2n't  +  s  — 2s'  i-^) 
\   a  a    y  a  ^  ^ 

/,7JV(0)\  xj 

+  «'.    -7^).e.— .cos.  (71/  — 2n7  +  £  — 2£'+^). 
\  da     J  d  ^  ^ 

Hence  we  get  in  iî,  the  following  terms,* 

/?=      iV'^i/'.e.cos.  (5n'/  — 2n/  +  5E'_2£  — ^  +  Z)') 
—  m\H.e.(io%.{b'n:t  —  2nt^bi—2i  —  ^  +  D) 

+  ia'.f-^j.G'.  e.cos.  (5w'/  — 2  7i/  +  5f'— 2.^  — ^  +  C") 

+  i«.  (— — j  .G.e.cos.  (5  7t'/  — 2ni  +  5/— 2s  — ra  +  C). 

To    obtain    the    corresponding    part   of     d'7?,     we    must   vary    the    angle 
[3997']     2jj/^  —  jj^^     jj^   j^l^g   terms  multiplied   by  H'  and  G';t    but   in   the  terms 

[39954]  quantity  ?i'i-|-£' — ra' ;  by  which  means  it  becomes  as  in  the  first  line  of  [39956]; 
then  putting  !  =  2,  it  becomes  as  in  the  first  term  of  [3995].  The  same  changes  being 
made  in  [3984],  which  was  derived  from  [3984n],  it  becomes  as  in  [3996]  ;  observing 
that  when  the  angle  3  n' i  —  nt-\-Z^  —  i  —  «  —  ■s/  [3984]  is  decreased  by  the  quantity 
nV  -\-  s' — ra'    [3995fc],  its  sine  becomes 

[3995i]  sin.  (2  w' ^  —  n  <  +  2  s'  —  s—  ^ )  =  — sin.  (n  < -  2  «'<  +  s  -  2  £'+  ra) , 

as  in  the  first  line  of  [3996],   and  its  cosine  is  as  in   the  second  and   third  lines  of  the 
same  expression. 

*  (2515)    Substituting,  in  [3996],  the  values  of    hr,    hv,    5/,    <5  y'    [3992-3994'], 
[3997a]     reducing  the  products  by  [17—20]  Int.,  and  retaining  only  the  terms  depending  on  the 
angle     5  ii! t  —  2?i<,     it  becomes  as  in  [3997]. 

t  (2516)    The  characteristic    d'   [3980]   affects  only  the  angle    2  m'!',    in    [3995],  so 
[3998o]     that    in   these  terms  we  shall  have     à'.^nt  —  'i.n  t)  = —  '2,n  dt  ;     but  d'   aflects  the 

the  whole  values  of      ~7  ,    ^  f',     consequently  also   the  whole  of  the  angle     3  n  t  —  nt. 


VI.  il.  §16.]    DEPENDING  ON  THE  SCJUARE  OF  THE  DISTURBING  FORCE.         141 

multiplied    by  H  and    G,    we   must  only   vary     2  n't;      hence   we   obtain     [3997"] 
a'd'B=  —  (ôn—n).clt.a'j\'^'>\H'.e.sm.{:in't~2nt^5s—2s  —  r.~\-D') 

_j.(5„'_„).rf^„'aY''^VG'.e.sin.(5«7  — 2H^  +  5a'-2£— ra+C) 

4--2n'tlt.a'JY^'>\H.e.sm.(5n'i  —  2nt4-5.'  —  2s  —  a^D) 

[3998] 

-~-^].G.e.sm.(5n't  —  2nt-{-5e'  —  2E—zi-\-C). 
The    term        N^'K  e'.  cos.  Çti  t  —  2  n' t  +  s  —  2  s'  +  z,') ,        arises    from    the 

r3998'l 

development  of  the  term  of  iî,  represented  by    ^''.  cos.  («' — v)*  [3d95f'\  ;  ' 

which  occurs  in  the  terms  [-3994,  .3994'],  which  are   multiplied   hy    G',  II';    so  that   in 

these  terms  we   shall  have       d'.[3n't  —  n  l)  =^3  n' c1 1  —  ndt.        Subtracting  [3998a]     [39986] 

from  this,  we  get 

d'.  {5n't—2nt)  =  d'.(3ji't—n  <) —  d'.  {nt —  2n' t)  =  {5  n'—n)  .  d  t,  [3998e] 

for  the  dlTerential  of  the  angle     5  n' t  —  2?!.^,     which  occurs  in  the  terms  of   R  [3997], 
depending  on   G',  11'  ;  it  being  evident,  that  the  angle     5  ft' t  —  2  n  t     is  produced  in  these 
^    terms  by  combining  the  angles     3  n' t  —  nt,     ni  —  2  n't,     as  in   [3998c].      Substituting     [3998ci] 
this  in  the  differential  of  the  first  and  third   lines  of  [3997],  taken  relatively  to   d',    we  get 
the   first    and    second    lines  of   [3998],   containing    the    flictors     G',    H',    as    in    [3997']. 

or 
Again,   the  characteristic  d'  [3930]  does   not  affect      —,    îi  v,      so   that  in   their  values 

[3992,  .3993],    which    contain   the    factors     G,    H,    we    have        d'.{3n't  —  nt)  =  0; 
subtracting  from  tliis  the  expression   [.3998n],  we  get 


[3998e] 


d'.  (  .5  7i't  —  2ni)  =  d'.{3n't—nt)  —  d'.  {nt  —  2n't)=2  n' d  i  ;  [3998e'] 

which  is  to  be  substituted  in   the   differenlial   of  tlie  second  and  fourth  lines  of  [3997], 
taken  relatively   to    d',   to   obtain    the    third    and    fourth    lines   of  [3998],  containing  tlie 
factors   G,  H,    as  in   [3997"].      The  whole  value  of    d'^    is  to  be  mukiplied  by  a',  to    '"^^^^•^^ 
obtain    ddR   [3998]. 

*    (2517)    We  have  seen,  in  [3995/],  that  the  second  term  of  [3995], 

./V'".  e'.  COS.  (  /i  ^  —  2  n't-\-s—2  i'  +  to'),  [3999a] 

is  derived  from  a  term  of  i?,  of  the  form  .,4^".  cos  (i;' — v),  corresponding  to  i=\; 
being  of  the  same  form  as  [3977(/].  Now  tlie  effect  of  the  substitution  of  the  variations 
of  or,  (5/,  Ô  (',  dv',  in  tlie  development  of  this  quantity,  having  been  computed  in  [3978], 
we  may  deduce  from  it  the  terms  of  R  [3999],  corresponding  to  the  present  case,  by  a 
similar  method  of  derivation  to  that  made  use  of  in  [3995/i— /].  Thus,  instead  of  the  ^^^^^^^ 
VOL.  III.  36 


142  PERTURBATIONS  OF  THE  PLANETS,  [Mtc.  Cél. 

r3998"l     ^^  must  therefore  vary,  in  this  term,     a    hy    6  r,    a'    by    ô  r',    n'  t  —  nt    by 
i  v — 6v,    and  we  get  the  following  expression, 

R=.       N^'K  e'.  (6  v'  —  6v)  .  sin.  {n  t  —  2n' t  +  s  —  2s'  +  v>') 
[3999]  +  a.  ( -— —  )  .  e'.—  .  COS.  (n  t  —  2  n'?;  +s— 2  e'  +  jj') 


(/  a 


a 


[4000] 


+  «'.  [~T-r     .e'.  — .COS.  (n^— 2n'^  +  f  — 2s'  +  ï5'). 

\    ail     J  a 

Therefore  the  part  of     a'd'B,     relative  to  these  terms,  is* 

a'à'R  =  — i.{5n'—n). lit. a  JV-^'.H'.e'. sm.(5n't—2ni +  5^—2  s  —  z^'-]-D') 

///jV(i)\ 

—  i.(5?i'— nj.f/i-.a's.  f-— -j.G'.e'.sin.  (5M'i  — 2m<  +  5s'— 2s— to'+C) 

+  n'(Z<.aW'.H.c'.sin.(5n'^  — 2n<  +  .5='— 2s— ûj'  +  D) 

—  ?i'rf^.o«'.  ^-^\G.e'.sin.(5?).'/  — 2Ki'-)-5s'— 2j— îj'+C). 

The  values  of    M<%    iV/'^',    M'*',    M' =>,      are  determined  in  the  formulas 

[4000']     Qf  ^^^  jjy  changing  the  quantities  relative  to    m    into  those  relative  to    m', 

and  the  contrary   [3975a,  6].t     The  values  of  A'^"*  and  N'-^^  are  determined 

operations  mentioned  in   [3995?],  we  must,  in  the  present  case,  change  the  factor  M'-"''.  e'" 

r3977el  into  A'"',  e'  ;    and   decrease   the   ani^le  which   is   contained   under   the   sign   cos., 
[3999cl     •-  J  '  o  c-  J 

'■  by    n't-\-e' — to';     by  which  means  [3977e]  becomes  as  in  the  second  line  of  [39956], 

[3999(i]    or  tlie  second  line  of  [3995],  supposing    ?'=1.      Now  making  the  same  changes  in  [3978], 

which  is  derived    from    [3977e],   it    becomes    as    in    [3999]  ;    observing    that   when    the 

angle      3n'i  — nt-{-3^—s—2-a'    [3978],    is  decreased    by      n't-\-i  —  ia'    [3999c], 

it  becomes     2  )/<  — n  <-(- 2  s'— s  — to'=  — (  ji  <  — 2«'<  +  e  —  2  s'+ra') . 

*  (2518)  The  function  [4000]  may  be  deduced  from  [3999],  by  the  method  we  have 
used  in  computing  [3997]  from  [3996].      It  may,  however,  be  deduced  more  easily  from 

[3999/]  [-3995^  3997J .  by  changing  JV*»',  e,  ra,  6v,  ôv',  into  .V<'>,  e',  to',  iSv,  i&v',  respectively. 
For  by  this  means,  [3996]    changes  into    [3999];    and   H,    H'    [3993,  3994']   become 

L        ^■'    i  H,  I  H',  respectively.     These  changes  being  made  in  [3998],  it  becomes  as  in  [4000]. 

f  (2519)    If  we  put    i  =  — 1,    in  the  terms  of  R  [1011],  depending  on    e,  e',    and 
[4000a]     retain  only  these  two  terms,  putting  also    .4'~'>  =  .4<''  [954"],  we  get,  for  this  part  of  R, 
relative  to  the  action  of  Saturn  on  Jupiter, 

R=^  —  -~.]a.[- —    —  2^<')^.e.cos.  {2nt  —  ntA-2s  —  s  —  zi) 
i     (        \  da    /  S  ^  '  ' 

[40005] 

—  ^  ■\<''-  ('-TT^W4^^='^.e'.  cos.  (2nt  —  v!t-\-2i  —  s  —  z^'). 


VI.  il.  §  16.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         143 

by  the  equations, 

a'A'^(»)=— 2m.rtVi'-'— im.  ««'.  (-^)  ;  [400i] 

a'  iV<"  =      m  .  «' .  J('>  —  i  m  .  a'\  C^^  •  [4001'] 

Connecting  together  all    these  partial  expressions  of     a'A'R,     we   obtain 
a  term  of  this  form,* 

a'à'R  =  m  n'.  I.dt .  sin.  {5n' t  —  2nt  +  5^' — '2,^  —  0) .  [4002] 

Hence  the  term     3  a  ffn  d  t .  d' R,     of  the  expression  of    <5  v',    givesf  [4002] 

iv'=  —  ,^"'''''''\.sm.  (5n't  —  2nt  +  ôs'—2s  —  0).  [4003] 

[5  II  —  2  II)-  ^ 

This  is  the  most  sensible  term  of  the  great  inequality  of  Saturn,  depending 
on  the  square  of  the  disturbing  force. 


[4000c] 


Changing,  reciprocally,  ibe  elements  of  m'  into  those  of  m,  we  get  the  corresponding  part 
of  -R,  relative  to  the  action  of  Jupiter  on  Saturn.  Comparing  this  with  the  assumed 
form  [-S^QS],  after  having  changed  the  signs  of  all  the  terms  contained  under  the  sign  cos., 
in  [3995],  we  get  the  expressions  of  JV'»,  ^'"    [4001,  4001']. 

*  (2520)    Adding  together  the  parts  of    a  d' R    [3982,  3985,  3989, 3991,  3998,  4000], 
and  putting,   for  brevity,       T^  =  5nt  —  27it-{-5s' — 2e,       we   get  a  series  of  terms    [4002a] 
of  the  first  form  [4002f]  ;   /'  being  used  for  brevity,  for  the  coefficients,  and    O'    for  the 
quantity  connected   with    Tj.      Developing   this  by   [23]  Int.,   we   get   the  second    form 
[4002c  or  4002fi?J  ;   in  which  we  may  substitute 

2./'.cos.  0'=mM'. /.cos.  O,         2./'.  sin.  0'=  — mn'. /.  sin.  O,  [4002J] 

and  we  obtain  the  first  form  [4002e],  which  by  means  of  [22]  Int.,  becomes  as  in  the 
second  form  of  [4002e],  agreeing  with  [4002], 

a'd'R  =  dt.-Z.r.  sin.  (Ts  -\- 0')=^dt  .S. .  F.  {sin.  T^  .  cos.  O'+cos.  Tj .  sin.  0'\  [4002e] 

=  (/  ^ .  sin.  Tj  .  2  .  /'.  cos.  O'-^d  t .  cos.  T^  .  2  .  /'.  sin.  O'  [4002(f| 

=  mn'.I.dt.\sm.  T,  .  cos.  O  —  cos.  T5  .  sin  0\  =  mn'.l.  dt  .sm.  (T.  —  O).      [4002e] 

t  (2521)    Multiplying  [4002]   by     S  n' d  i ,      and   then   integrating   it  twice,  relatively 
to  t,  we  get,  for    3  a'ffn'd  t .  à'R,    the  expression  [4003]  :  and  this  quantity  is  evidently     [4003o] 
the  most  important  one  in  the  value  of  u  v,  depending  on  the  term  now  under  consideration, 
included  in  the  expression  [3715m]. 


144 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Céî. 


[4003'] 


[4004] 


[4005] 


If  the  expression  of  R,  divided  by  the  disturbing  mass,  be  the  same 
for  Jupiter  and  Saturn,  we  shall  have,  as  in  [1208],  the  coiresjjonding 
inequality  of  Jupiter    6  v,    by  substituting  the   preceding  value    &v'    [4003] 

in  the  formula 

m'  \/tt' 


6V  = 


m\/a 


.6V\ 


but  the  value  of  ^4'"  [3775c]  is  not  the  same  for  the  two  planets, 
therefore  the  terms* 

ilf  C).  e'\  COS.  (3  m'  ^  —  /U  +  3  .-'—  s  —  2  ^J)  ; 

iV">.  e'.  COS.  (nt  —  2n't  +  s  —  2 e  +  ^')  ; 

divided  by  the  disturbing  mass,  are  different  for  each  of  them.  But  it 
follows,  from  [1202],  that  by  noticing  only  the  terms  having  the  divisor 
(5  n' —  2  n)",     we  shall  have  in  this  case,t 

m.fdR^+in'.fd'R^O  ; 


[4004a] 
[4004ft] 


[4004c] 
[4004i] 


*  (2522)  The  terms  mentioned  in  [4004]  are  derived  from  «3'^\  cos.  (îj' — v),  as 
it  appears  in  [3976',  .3998']  ;  but  the  value  of  A'-'''  is  not  the  same,  in  computing  the  action 
of  m  upon  m' ;  as  it  is  in  computing  the  action  of  m'  upon  m  [377.5c].  Now  we  have 
already  remarked,  in  Vol.  I,  page  651,  that  the  method  of  finding  the  inequality  of  Jupiter 
from  that  of  Saturn,  by  means  of  the  formula  [1208  or  4003'],  is  not  applicable,  without 
some  restriction,  to  the  computation  of  terms  of  the  order  of  the  square  of  the  disturbing 
force.      This  is  evident  from  the  consideration,  tliat  in  the  equation 

ni.fdR^m'.fd'R'  =  0       [1 202] , 

from  which  the  formula  [1208]  is  derived,  terms  of  the  third  order  in  m,  m'  are  neglected, 
which  is  equivalent  to  the  neglect  of  terms  of  the  second  order  in  R,  R' ;  being  of  the 
same  order  as  the  terms  computed  in  [3982 — 4002]. 


t  (2523)  This  formula  is  corrected  for  a  typographical  mistake  in  the  original  work, 
[4005a]     and   is  the  same  as  in    [4004c]  ;    terms  of  the  third  order  in    m,  m    being   neglected. 

We  have  already  spoken  of  the  different  meanings  of  the  symbol  R,  and  it  may  not  be 

amiss  again  to  repeat,  that  ?»  is  the  mass  of  Jupiter,  w'  that  of  Saturn  ;  also  in  formula 
[40056]      [4004c],  the  value  of   R  corresponds  to  the   action  of  rd  on  m  [913],  and   R'  to  the 

action   of  m  on  ?«'  [1199'].      These   are  changed   in   the   present  article  to  R^  [4005'] 

and  R  [3974''],  respectively. 


VI.  il.  §16]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        146 

R^  being  tvhat  R  becoiries  relatively  to  the  action  of  Saturn  on  Jupiter,  and     ,Af.,.r,^ 
the  differential  characteristic   d    referring  to   the   co-ordinates   of  Jupiter.* 


*  (2524)  Substituting  &v'  [4003]  in  the  formula  [4003'],  we  get  the  corresponding 
inequality  of  &v  [4006].  This  method  of  deriving  5v  from  <)v',  would  be  sufficiently 
accurate,  were  it  not  for  the  terms  of  the  third  order  in  m,  m',  omitted  in  [4004c,  4003'].  These 
neglected  terms  make  it  necessary  either  to  correct  the  result  obtained  in  [4006],  or  to  compute, 
tn  a  direct  manner,  the  value  of  5v  from  the  formula  ôv^Saffndt  .dR  [3715Z].  Thus, 
for  the  terms  of  R,,  which  are  similar  to  those  of  R  [3978, 3984,  3988,  3990, 3996,  3999], 
we  must  compute  the  corresponding  values  of  adR^,  similar  to  [3982,  3985,  &c. — 4000], 
and  by  combining  all  of  them  together,  we  get  the  value  of  adR^,  corresponding  to  [4002]. 
This  is  to  be  substituted  in  [4005f],  to  obtain  the  required  inequality  5v,  which  is  to  be 
used  instead  of  [4006].  It  will  not,  however,  be  necessary  to  repeat  the  whole  of  these 
calculations,  since  we  shall  soon  show  that  the  terms  of  R,  of  the  form  and  order  in  the 
development  [3742],  combined  with  those  of  a  similar  development  of  R^,  satisfy  the 
equation  [4005],  when  we  except  the  terms  depending  on  A'-^\  and  notice  only  such 
quantities  as  have  been  under  consideration  in  this  article,  namely,  those  which  are  of  the 
order  of  the  square  of  the  disturbing  force,  and  depend  on  the  angle  5  n' t  —  2nt. 
For  if  we  put 

A  =  cos.  (  v' —  v)  —  ^7®.  cos.  {v'  —  I' )  ~t~  4  7^'  ^^^-  ( '^'~H * )  > 

X 

B  =^  —  {r^  —  2  r  r'.  cos.  {v' —  i'  )  4~  '"' '^  ^      ^ 

3.  . 

4"  ^7^-\cos.{v' — v)  —  COS.  (  !)'-[- 1' ) }  •  \r^ — 2rr'.  cos. (d' — v)-{-r'^\      ^  ' 

we  shall  obtain  the  value  of  R  [4005/],  corresponding,  as  in  [3974''],  to  the  disturbing 
force  of  Jupiter  upon  Saturn  ;  the  expression  is  derived  from  [3742],  by  changing  m,  r,  v 
into  m',  /,  v',  and  the  contrary.  Moreover  R^  [4005/',  4005']  corresponds  to  the  action 
of  Saturn  upon  Jupiter,  being  the  same  as  in  [3742], 


R=m.^  .--if-mB; 


[Action  of  Jupiter  on  Saturn.] 


R/=^  m'A  . \-m  B  ;  [Action  of  Saturn  on  Jupiter.] 


respectively,  in  [3975—3991];  also  JV'^    JV»>,    into    -.A*'»',    -  .JV'"  [3995— 4001']  ; 
or  in  other  words,  we  may  compute  the  parts  of  R^ ,    depending  on  B,  by  multiplying  the 
VOL.  III.  37 


[4005i'] 

[40056"] 
[4005c] 

[4005rf] 
[4005e] 

[4005/] 

[4005^-] 

[4005/i] 
[4005i] 

[4005*] 

[4005/] 
[4005/'] 


If  we  neglect,   for  a  moment,  the  term   A,   we  shall    have      R^mB,      R,  =  m'  B  ; 

I 

whence      R,^  —  .R;      so  that  the  terms  of  R^,    corresponding  to  R  [3975],   maybe     [4005m] 
found  by  changing    M^'>\  M^'\  M'^\  M^^\    into    -.J/«\    -  .M^",    -'.J/<2',    -.JfO), 


[4005»!] 


146  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

Hence    it    follows,    that    the    inequality   of   Jupiter,    corresponding    to    the 

corresponding  terms  of  it  [3978,  3984,  &jc.]  by     — .      In  finding  tlie  differentials  relative 

to  d,  we  shall  proceed  in  the  same  order  as  we  have  done  in  finding  those  relative  to  d' 

[4005o]     [39S2ff,  8ic.],  observing  that  d  does  not  affect     Sti't,     in  the  angle     3  n't — nt,     which 

[4005;/]     occurs  explicitly  in  [3975].      Hence  we  shall  have     d  .  {3  n't  — ni)^^  —  n  dt,      similar 

6r' 
to  [3982rt]  ;  moreover,  as  the  sign  d  does  not  affect  the  values  of    —,   Sv',    the  differential 

of  the  angle     nt — ■2n't,     which  occurs  in  these  values,  or  in  the  terms  connected  with 
[4005î]     £',  i^'  [3974',  3974],  is     d  .  {nt~2n'i)  =  0.      The  difference  of  these  two  expressions, 
corresponding  to  the  equation  [3982c],  is 

[4005r]  d  .  {5  n'  t  —  2  n  t)  =  d  .  {3  n  t  —  71 1)  —  d  .  {71 1  —  2  n'  t)  =  —  )i  d  t  ; 

[4005r']  now  we  have  very  nearly  5  71' — 2  ?i=  0  [3818rf]  ;  and  the  inequalities  S  v,  iv',  under 
consideration,  are  very  small,  as  we  shall  see  in  [4431/]  ;  therefore  we  may  put 
—  J!  =  —  ( 5  71'  —  n),     and  the  preceding  expression  becomes 

[4005s]  d.{57it—2nt)^  —  (  5  n' —  71)  .  d  t  ; 

which  is  equal  to  that  of  d'.  ( 5  m' t  —  2  7it)  [3982c],  but  has  a  different  sign.  Hence, 
by  noticing  only  the  part  of  R,  depending  on  B,  and  connected  with  the  factors  E',  F', 
we    have     d/?  =  —  d'iî  ;      substituting  this  in  the    differential    of  R^    [4005»j],    taken 

relatively  to  d,  we  get      dR=~.dR^ .A'R;      which  is  easily  reduced   to  the 

[4005u]    fo'™     ;«  .diî, -[-?«'.  d'/{  =  0   [4005].      In  like  manner,  the  differential  d  affects  the  whole 

of  the  values     —,    &v    [3972,  3973],     depending   on    the    factors    E,    F  ;    so    that    the 

differential  d,  of  the  angle     71 1 — 2iH,     connected  with  these  terms,  is 

[4005i']  d  .{7it  —  2  7i't)  =:  ndt  —  2n'd  t . 

Subtracting  this  from  [4005j:>],  we  get 

d.{5n't  —  27it)  =  d.{3n't  —  ni)  —  d.{7it  —  27i'i)=^27i'dt  —  27idt: 

and  by  substituting     2  m'  —  2  }i  =  —  3  ?i'    [4005/-'],  it  becomes 

d.{5  7it  — 2  71 1)=  — 3  71' dt  =  —  d'. {5  n't— 2  nt)      [3982^]  ; 

r4005rl     hence,  for  these  terms,  we  also  get,  as  in  [4005^],    dR^ — d'R  and  ?«.di?,-}-m'.d'-R  =  0. 

The  same  result   holds  good  when  the   terms  of  R,   instead  of  depending  on  the  angle 
[4005yJ    3  n't  —  71 1    [3975],  have  other  forms,  as  for  example,     nt  —  2  7i' t    [3995]  ;   which  are  to 

be  combined  with  the  corresponding  terms  of    S  7-,  ôv,  (5  /,   6  v',    so  as  to  produce  the  angle 

5  7i'i  —  2  7it.       Thus,  if  instead  of  the  particular  values  of    R,     —     [3975,  3974],    we 
assume  the  following  general  values, 
[4005î"  R  =  M.cos.{  i\  n't  —  i^nt  +  Jli),        ~  =  F'.  cos.  (  it  n  t  —  i'.,  n'  t -\- A^^)  ; 


[400.5«P 
[4005w'i 


VI.  ii.  ^S 16.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        147 
preceding  expression  [4003],  is 

^  3m. «ay-  ^  ^■^^^.Q^,^_2nt-\-5s—2e  —  0).  [4006] 

(5ji'  — 2n)2  ^ 


in  which     i\  -j-  i'^  =  5  ;     {^  -(-  i,  =  2  ;      we  shall   find   that  the   products   of  these   two     [4005i'] 
expressions,  contained  in  a  function  similar  to  [3978],  will  produce  a  term  depending  on 
the  angle      5n't—2nt,      as  in    [-3979].       In   this  case,   the   equations    [3982c,  4005r] 
become,  respectively,  by  suhstituting     i\-{-i'„  =  5  [400.5-'],  [400(Ja] 

d'.(5ii't  —  2nt)^zà'.{i'i  n'  t  —  iiiit)  —  à'.{^nt  —  i'^  n'  t  ) 

[4006i] 
=  i\  n  (It  —  {^i^ndt  —  i'o  n'  d  ()  =  5  n  d  t  —  i.^  ndt  ; 

à..{bn't  —  2nt)=^à.{i\nt  —  i\?U)  —  d.  (îoni  —  i'.^n't)^^  —  i^ndt.  [4006<;] 

The  sum  of  these  two  equations,  substituting    iy  -|-  to=  2  ;    5  ?j'  —  2  ?«  =  0  [400.5cr',  /],  is 

ù'.{bnt—2nt)-i^A.{biît  —  'int)^bn'dt—2ndt  =  Q,     or     à'R^àR^Q,       [4006rf] 

as  in  [400.5^]  ;  and  from  this  we  get,  generally,  as  in  [400.5x,  4005] ,    m.àR^-\-m' .à'R=zO.     [4006e] 
Hence  it  follows,  that  if  we  put    àvy,    i5z).,,    for  the  parts  of   èv,    of  this  form  and  order, 
dependuig  on  Jl,  B,  respectively;  also  &v\,   ôv'ç^,  for  the  similar  parts  of  ôv',  we  shall  have 

5  D  =:  5  Di  +  5 1>2  ;  ôv'  =  Sv\-{-Sv'„;  [4006/] 

and  the  formula  [4006e]  gives,  as  in  [1202,  Sic],  the  following  expression,  similar  to  [4003'], 


[4006e'] 


Sv^=  —  5v'2."^.  [meg] 

my  a 

From  this  formula  we  may  compute  5t)o,  after  having  found  or'j,  by  a  direct  process 
similar  to  that  used  in  [3975 — 4003]. 

In  computing  the  terms  of  avy,  àv\,  depending  on  A  [4005A],  we  may  neglect  the 
two  terms  containing  y^,  for  the  same  reasons  as  in  [3990ff— c].  Then  we  shall  have 
simply     ^  =  cos.  (î;' — v)  ;     hence  the  corresponding  parts  of  R,  R,  [400.5/,/'],  become     [4006/i] 

R  =  m. ^  .cos.{v'—v);  R^=m'.-^^.cos.  .{v'—v).  [400fo-] 

These  quantities  evidently  depend  on  the  term  connected  with  the  coefficient  A  <'',  in  the 
development  of  —  [954,  957],  as  is  evident  by  the  substitution  of  the  values  [952,  953]. 
Hence  we  have,  by  noticing  only  this  part  of  A'-^\ 

A'^'>  =  m  •  -J  ;     in  computing  êv\,  arising  from  the  action  of  Jupiter  on  Saturn  ;  [4006^] 

^'i>=m'.  —  ;     in  computing   Sv,  arising  from  the  action  of  Saturn  on  Jupiter.  [4006/] 

Now  A^^'  occurs   only  in    the   development  of  the   term    .^'". cos.  ( r' — v);     and   it   is     [4006m] 


148 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


17.    In  the  inequalities  of  Jupiter  and  Saturn,  in  which  the  coefficient 


[4006']     of    t    is   neither     5n'- 


nor   differs   from   it    by    the   quantity    n,    in 


[4006n]  therefore  found  in  JJf*"'  [3976,3976'],  also  in  JV'("  [4001']  ;  but  not  in  M^'\  M'--\  M"', 
[400(3o]  JV'"'  [3983,  3986,  3989",  3995']  ;  so  that  in  these  last  terms  we  shall  have  (5  Uj  =  0, 
[400G/)]     5^'j  =  0,     à'Vç,=^iv,     (5  î)'g  =  (5 1)' ;      consequently  the   value   of    5v     may   be   correctly 

obtained  from  i5  v',  in  these  cases,  by  means  of  the  formula  [4003'].  A  different  process 
[4006?]     must  be  used  with  the  terms  depending  on  M'-^^,  JV*'\  which  contain  A^^\      For  we  must 

compute  (5  ti'j  in  a  direct  manner,  by  means  of  the  value  of  ^'"  [4006Zr]  ;  also  dv-^,  from 
[4006r]  [4006Z]  ;  by  a  process  similar  to  that  used  in  computing  &v'  or  &v'^,  in  [3982,4002']. 
[400C«]     Having  thus  obtained    i5  Dj  ,    ùv\,    iv'.^,    we  get    àv^,    by  means  of  the  formula  [4006^], 

and  then  by  substitution  in  [4006/"],  we  obtain  the  values  of   5v,    Sv',    corresponding  to 

r.««^  „  these  terms.  These  remarks  are  not  restricted  to  the  two  forms  of  R,  treated  of  by  the 
[4006s ] 

author  in  [3975,  .3995],  but  apply  generally  to  others  of  a  similar  nature,  contained  in  the 

general  table,  which  we  shall  give  in  [4006zt]. 

In  addition  to  the  terms  of   R,    depending  on  the  angles     3  n't  —  ni,     ni — 2n'i  ; 
[4006<]      treated  of  by  the  author  in  [3975,  3995]  ;  there  is  an  infinite  number  of  a  similar  nature  ; 

some  of  which  are  deserving  of  peculiar  notice,  on  account  of  their  magnitudes  ;    and  one 

of  them  is  of  nearly  the  same  order  as  those  we  have  already  noticed.      The  20  forms  of 

R,    S  7-,    5v,    êr,    ôv',    Sic,    producing  the  angle     5  n't  —  2  n  i ,     are   contained    in    the 

annexed  table.      Thus  the  form  which  is  marked  with  the  number  6,  includes  the  terms 

of   R,    depending  on   the   angle     3 n't  —  nt,      as  in 
;  the  first  form  assumed  by  the  author  in  [3975]  ;  and 

when  this  is  combined  with    6r,  5v,  &:c.,  of  the  form 

2n't—nt,  it  produces  terms  depending  on    5n'i  —  2nt, 

as  in  [3979].      We  may  also   take  these  angles  in  an 

inverse  order,  corresponding  to  the  accented  numbers, 

supposing,  as  in  the  number  6',  that  R  depends  on  the 

angle    2n  i  —  n t ,     corresponding  to  the   second  form 

of  the  author,  in  [3995],  and  ér,  5v,   he.  depend  on 

the  angle    3 n't  —  nt .      The  numerical  values  of  these 

terms  of  ^i',  5v',  are  given  inaccurately  in  [4432,4488]; 

as   was    first  observed   by   Mr.  Plana,    in  the   second 

volume  of  the  Memoirs  of  the  Astronomical  Society  of 

London  ;  in  which  he  has  given  the  calculations  of  the 
[4006d]      separate  terms  at  full  length  ;  and  has  also  noticed  the  terms  of  R,  of  the  forms  5',  3,  4  ; 

observing,    however,    that   they  have    hardly  any  sensible   effect    in    the   complete   values 

of   &v,  5  v'.      The  final  values  of    ôv,  ô  v',    computed  by  Mr.  Plana,  by  a  direct  process, 

and  independently  of  each  other,  did  not  satisfy  the  equation  [400-3']  ;  and  this  numerical 

result,  he  considered  as  a  demonstration  a  posteriori,  that  this  formula  could  not  be  applied 
[4006!^]    ^^  ^j^  ^1^^^^  jg^.^^^^  ^j.  jj^g  ^^,jg|.  ^f  ^jjg  square  of  the  disturbing  masses.      In  consequence 


[4006«] 


No. 

Coefficienl3  of  (  in 
the  terms  of 

R. 

Coefficients  of  t  in 
tlie  terms  of 

Sr,  év,  or',  iv'. 

V 

2! 
3' 

4' 
5' 
6' 

1 

2 
3 

4 
5 
6 

0 

n' 

2ji' 

3n' 

n'  —  n 

3  n'  —  n 

5  n'-  2  n 
An'—2n 
3n'  — 2n 
2n'— 2n 
An'  —  n 
2n'  —  n 

v=n'—n; 

{  =  any  positive  integer. 

7 

8 

9 

10 

5n'—2n-\-i\i 
5n' — 3  ?i  -|-iv 
5n' — 4?i-|-iv 
5n'  —  5n-\-iy 

I  V 

t  V  —  n 
iv  —  2n 
iv  — ■  3  n 

r 

8' 

9' 

10' 

No. 

Coefficients  of  £  in 
tlie  terms  i>f 

Sr,  iv,  6r',  6v'. 

Coefficients  of  (  in 
the  terms  of 

R. 

VI.  ii.  §17.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         149 


Jupiter,  or   n'  in  Saturn;   we  must  increase    nt    and    n't    by  their  great     r^^Qg,,, 
inequalities    depending    on      bn't  —  Int.       For   we    have    seen    [1070"], 


of  tliese  remarks,  La  Place  resumed  the  subject  in  a  memoir  published  in  the  Connaissance 
des  Terns  for  the  year  1829  ;  in  which  he  tacitly  admits  the  inaccuracy  of  the  application  of 
the  formula  [4003']  to  all  these  terms  of  the  order  of  the  square  of  the  disturbing  forces  ;  and 
gives  a  new  formula  [400Si],  expressing  the  relation  between  the  complete  values  of  the 
terms  of  5v,  5  v',  like  tJiose  computed  in  this  article,  and  others  of  a  similar  form  and  order, 
calculated  by  Mr.  Plana  [4006v].  This  new  formula  has  been  called  the  last  gift  of  La  Place 
to  astronomy.  Upon  applying  the  numerical  values  of  ôv,  5  v',  given  by  Mr.  Plana,  to  this 
formula,  it  was  not  satisfied  ;  whence  La  Place  inferred,  that  these  numerical  calculations 
of  Mr.  Plana  were  incomplete  or  inaccurate.  Some  strictures  having  been  made  on  this 
formula  by  Mr.  Plana,  in  the  Memorie  dclla  Reale  Accademia  delle  Scienze  di  Torino, 
Tom.  XXXI  ;  it  was  followed  by  two  other  demonstrations  of  this  new  formula  ;  the  first 
by  Mr.  Poisson  in  a  memoir  published  in  the  Connaissance  des  Terns  for  1831  ;  the  second  by 
Mr.  Pontécoulant,  in  the  same  work,  for  1833.  In  the  memoir  of  Mr.  Poisson,  he  notices 
the  term  of  the  form  1,  in  the  table  [4006m],  and  shows,  that  it  is  of  sufficient  importance 
to  be  introduced  into  the  calculation.  Under  these  circumstances,  he  recommends  a 
revision  of  the  whole  calculation,  by  taking  into  consideration  all  the  forms  comprised  in 
the  table  [4006it],  which  produce  terms  of  i5  v,  Sv'.  of  any  sensible  magnitude.  This 
extremely  laborious  task  has  been  performed  by  Mr.  Pontécoulant,  who  has  given  the 
abridged  results  of  his  investigation  in  the  Connaissance  des  Terns  for  the  year  1833,  from 
which  we  shall  make  some  extracts,  in  the  notes  upon  the  twelfth  and  thirteenth  chapters 
of  this  book,  in  treating  of  the  orbits  of  Jupiter  and  Saturn.  These  results,  so  far  as  they 
relate  to  terms  of  the  forms  6,  6'  [4006?;],  computed  in  this  article,  differ  but  very  little 
from  those  of  La  Place  [4432,  4488],  except  in  the  signs  ;  and  upon  referring  to  the 
original  manuscript,  in  which  these  last  calculations  were  made,  a  mistake  in  the  signs 
was  discovered.  Finally,  Mr.  Pontécoulant  suggested  to  Mr.  Plana,  some  corrections 
which  were  necessary  in  his  work  ;  and  upon  the  revision  of  his  calculation,  it  was  found, 
that  the  results  were  almost  identical  with  those  of  Mr.  Pontécoulant  ;  these  corrected 
values,  combined  with  the  other  terms  of  this  kind  computed  by  Mr.  Pontécoulant,  are 
found  to  satisfy  very  nearly  the  new  formula  of  La  Place  [4008x].  We  shall  now  give 
the  demonstration  of  this  formula. 

For  this  purpose,  we  shall  use  the  same  notation  as  in  [1198],  in  which  M  represents 
the  sun's  mass,  m  the  mass  of  Jupiter,  in'  the  mass  of  Saturn  ;  x,  ij,  z,  the  rectangular 
co-ordinates  of  Jupiter,  referred  to  the  sun's  centre  ;  r  its  radius  vector,  &c.  ;  and  the  same 
letters  accented  correspond  to  the  orbit  of  Saturn.     Then  putting,  for  brevity. 


x^'+yy'+-'^' 


VOL.  III. 


w 


xx'+yy'+-' 


^lf^x'-xf+{y'-yf+{z'~zfl 


[4006x] 


[4006y] 


[4006z] 
[4007a] 

[40076] 

[4007c] 
[4007  (i] 


[4007e] 
[4007/] 

[4007e-] 


38 


150  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[4006'"]    that  these  great  inequalities  must   be  added  to  the   mean  motion,   in   the 

[4007/1]    we  get,  as  in  [949,1200],  by  observing  that    r^^x^-V-y^-^-z^    r'^=x'^-^y"^-^z'~  [ÇiW], 

[4007il  R  =  in  •  (iv'  -\-  X)  ;  [For  tho  action  of  Saturn  upon  Jupiter.] 

[4007/c]  R':=  m  .  (it)  -\-  X)  ;  [For  the  action  of  Jupiter  upon  Saturn.] 

Now  if  we  multiply  the  formula  [1198]  by  M-\-m-{-m',  it  will  become  of  the  form 
[4007o]  ;  for  the  two  first  terms  of  the  second  member  of  the  product,  or  those  in  the 
first  line  of  [1198],  may  be  put  under  the  form, 

[4007i] 


^{dx^  +  dy^  +  dz"~)    ,       ,3  {dx'^+dy-!i+dz"- 


dt^  '  dt^  ' 

of  which  the  first  line  is  the  same  as  in  the  first  line  of  [4007o].     Connecting  the  terms  in 
the  second  line  of  [4007?]  with  those  produced  by  the  second  line  of  [1198],  namely, 

{mdx4-m,'dx')^        {mdy-j-m'dy')-        (mrfz-j- m'rfz'p 

f*°°'"l dt^ dT^ ■ dV^ ' 

it  produces  the  second  line  of  [4007o]  ;  observing,  that 

??i^  d x^  -{-  m' -  dx'~  —  ( m  d x  -\-m'  dx'Y  =  —  2  m m'.  dxd x',     he. 

The  first  and  second  terms  of  the  third  line  of  [1198]  produce,  without  any  reduction,  the 
[4007;i]    third  line   of  [4007o],    and  the   last  term   of  [1198]    gives   the  last  of  [4007o],    using 
X  [4007^]  ;  hence  we  have 

constant  =  (  M+  m!).m.  ■ ^   -*  J^ '  -\- {M-\-m)  .m'.  ^ ^  ^ 


[4007o] 


[4007p] 


_  ,  Crfxrfx'     ,    dvdy'    ,    dzdz'") 

-2mm'.^-^^  +  -^  +  ^ 

+  2  .  (  JIf  +  m  +  7n')  .  m  m'.  X. 

Tr               1-11          1           r        dx'i  +  dif-  +  dz^           rfa:'2  +  rfy2  +  (/i'2       ,      ^^  ^        . 

If  we  multiply  the  values  of      /^^ — ,        f,o     [1199,1200],      by 

[M -\- m') .  m,      {M-{'m).m',     respectively;    and  add  the  products,  we  shall  get,  for 
the  first  line  of  the  second  member  of  [4007o],  the  following  expression, 

(^i+^')..,.^^J^,2/diï^  +  (J^f+>»)•m^f•^•7^'"'^-2/d'i^| 


VI.  ii.  ^^  IT.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        151 
formulas  of  the  elliptical  motion  ;   they  must  therefore  be  added  to  the  same 


If  we  substitute  this  in  [4007o],  we  shall  find,  that  the  term  having  the  divisor  r,  is 

2  m 

—  .  \ {M  +  m')  .{M+m)  —  {M+m+  m') .  31],  [4007p'] 

which,  by  reduction,  is     ;     and  in  like  manner,  the  term  depending  on  r ,  is     — ;; —  ; 

so  that  if  after  this  substitution  is  made,  we  divide  the  whole  expression  by  2,  and  transpose 
the  tenns  depending  on  d -R,  d'R',  we  shall  obtain  the  following  equation,  in  which 
nothing  is  omitted,  the  constant  quantity  being  included  in  the  signs  /, 

(  M  +  m')  .m..fàR  +  {M-\-  m  )  .  m'.fd'  R'=      m  m.  0  +  ^) 

,   /dxdx'-\-dydy'-\-dzdz'\ 

-  '"  '"  •  V dt'  —  )         ^^^^^^^ 

-{-  {M  +  m  -\-  m')  .mm'.y-.. 

We  must  now  consider  the  terms  of  this  equation  affected  with  the  small  divisor  5n' — 2n, 
and  ha\Tng  5 n't  —  2nt  for  the  argument  ;  these  temis  being  the  only  ones  which  can 
acquire  the  di\Tsor  (5»'  —  2n)^  by  another  integration  in  J'fdR,  ffd'R',  or  in  [4007)-] 
the  expression  of  the  longitudes  of  the  two  planets  [3715/,  »*]  ;  and  in  making  this 
investigation,  we  shall  reject  all  terms  of  the  order  in'*.  In  the  first  place,  we  shall 
observe,  that  the  expression  in  the  second  line  of  the  second  member  of  [40075']  ^'^^^  ^'^^ 
contain  such  tenns  of  the  order  ??i^,  as  is  evident  from  the  reasoning  in  note  819  [1201'],  [4007«] 
where  it  is  sho^^Ti,  that  these  terms  of  the  order  ?«^,  arise  fi'om  the  substitution  of  the 
elhptical  values  of  x,  x',  y,  ij ,  &c.  ;  and  to  obtam  terms  of  the  order  »i',  we  must  augment 
these  elhptical  values  of  x,  x,  Sic.  by  the  terms  depending  on  the  perturbations.  These 
terms  may  be  easily  obtained  by  considering  the  orbits  as  variable  ellipses,  in  which  we  may 
suppose  X,  x',  to  be  of  the  forms, 

x  =  ^1  -f-  5i  .  cos.  (n  /  +  Ci)  +  &:c.  ;  [4007<] 

x'  =:  Ay  +  B.2  .  COS.  (  n't  -)-  Co)  -j-  &c.  ;  [4007k] 

Ai,  B^,  Ci,  &c.,  c/^2,  Bo,  Cj,  &.C.  being  functions  of  the  elements  of  the  orbits. 
These  elements  for  the  planet  Jupiter  are  ;  the  mean  longitude  of  this  planet  nt  -\-  e; 
E  the  mean  longitude  of  the  epoch  ;  a  the  semi-transverse  axis  of  the  ellipsis  ;  e  the 
excentricity  ;  «  the  longitude  of  the  perihelion  ;  y  the  inclination  of  the  ellipsis  to  a  fixed 
plane  ;  and  è  the  longitude  of  the  ascending  node.  The  same  letters  being  accented,  [4007u"] 
represent  the  corresponding  elements  of  the  orbit  of  Saturn.  In  the  values  of  all  these 
elements,  the  secular  inequalities  are  supposed  to  be  included.  The  differential  of  the 
expression  [4007/,  u],  bemg  found  as  in  [1168'],  become 

dx  =  —  B,.ndt.  sin.  (n  /  +  C^)  —  &c.  ;  [4007t.] 

dx'=  —  Br,.n'dt.  sin.  {nt-{-  Co)  —  &c.  [4007w] 


[4007u'] 


152 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


quantities  in  the  development  of  R.     Let 
[4007]  R^H.  COS.  (i'  n'  t  —  int  +  A), 


[4007a-] 


[40086] 

[4008i'] 
[4008c] 

[4008rf] 
[4008e] 

[4008/] 


Tlie  product  dx  dx',  will  therefore  contain  only  periodical  quantities  of  the  form, 

H . cos.  {in't  —  int-\-E); 


H,  E,  being  functions  of  the  elements  of  the  orbits  ;  and  i',  i,  integral  numbers,  positive 
or  negative  ;  moreover  n't,  nt,  in  the  planetary  system,  are  incommensurable  quantities 
[1197"].  Now  if  we  consider  the  elements  as  variable,  their  variations,  corresponding  to  the 
great  inequalities  of  Jupiter  and  Saturn,   will  have  the  same  argument  as  these  inequalities, 

[i007y]  namely,  5  n  t  —  2nt,  and  they  have  5  ?i'  —  2  n  for  a  divisor,  as  is  evident  from  what 
we  have  seen  in  [1197,  1286,  1294,  1341,  1345'],  or  more  completely  in  the  appendix  to 
this  volume  [5872 — 5879].  Substituting  these  variations  in  [4007x],  and  reducing  by 
[17 — 20]  Int.,  we  shall  obtain  terms  having  this  divisor;  but  it  is  evident,   that  they  will 

[4007z]  not  have  the  same  argument,  except  z'  =  10  and  i  =  4;  in  which  case  /J"  will  be  of  the 
order  e^  [957^''',  &,c.],  which  is  neglected,  because  we  notice  only  terms  of  the  third  order 
relative  to  the  excentricities  e,  e',   and  of  the  same   order  relative  to  the  masses    in,  mf. 

[4008a]  The  same  remarks  may  be  made  with  regard  to  the  products  d  y  dy',  d  z  d  z'  ;  hence  we 
conclude,  that  the  fonction  included  in  the  second  line  of  [4007^]  does  not  contain  terms 
of  the  order  n?  or  it?,  which  has  for  its  argument  5h7  —  2)i<,  and  for  divisor  5/i' — 2?i; 
so  that  we  may  substitute,  in  [40075],  ^^^  following  expression. 


■mm. 


dxdx'-\-dy  dy'-\-dz  dz' 


0. 


In  the  fonction  comprised  in  the  third  line  of  [4007 (^],  namely,  (./li-f-w  +  ?»') .  mm'.  X, 
we  may  change  the  factor  M  -{-  m-\-7n'  into  ./If  ;  it  being  evident,  that  the  neglected 
quantities  do  not  comprise  terms  of  the  order  m^,  having  the  argument  5  n' t  —  2nt 
and  the  divisor  5n'  —  2n.  Then  substituting,  in  X  [4007^],  the  elliptical  values  of  x,  x' 
[4007<,  u],  and  the  similar  values  of  y,  y',  z,  z'  ;  it  becomes,  by  development,  of  the  form, 

■k  =  A-\-K.cos.  {5n't  —  2nt-J[-  I)  +  Q., 

in  which  A  represents  the  part  depending  on  the  argument  zero,  and  Q  all  the  terms 
depending  on  angles  of  the  form  i'n't-\-int,  i',  i,  being  integral  numbers,  positive  or 
negative,  excluding  those  pi-oducing  the  argument  5  n't  —  2nt,  which  is  connected 
with  K,  and  the  argument  zero  connected  with  A  ;  hence  we  have 


(.W  +  w  +  m)  .mm!  .\  —  M  .  m-rri  .\A-\-  K .  CQ's,.{'ô'){  t  —2nt  ^  I)  A^  q}. 

The  quantity      mm'.—    [4007<7],    is  of  the  third  order  in  7n,  in,    and  as  the  value  of  r 

[4008g-]      contains  no  term  having  the  divisor    5  ?i' — 2n,    except  it  be  of  the  order   ??/,    we  may 
neglect  this  term,  because  it  produces  nothing  except  of  the  order  m""  ;  and  the  same  is  to 


VI.  ii.  §1~]  DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        163 

be  any  term  of  this  development  ;   and 

6v  =  L.  sin.  (i'n't—int-\-B),  [4008] 


VI 


be  observed  relatively  to     m  m'.—.      Substituting  these  and  [40086,/]   in  [4007^],  we  get 

M.  { mfdR  +  m'fd'R' }  +  m  m'.  \fdR  +/d'jR'  \r:^M.  m  m'.  \  A+K.  cos.  (5  7t7 — 2 n  ï  +/ )  +  Q  ^     [4008A] 

We  shall  represent  by    (R),  {R'),    the  parts  of  R,  R',    respectively,  of  the  order   m  ;      [4008t] 
then  using  the  characteristic  (S  of  variations,  we  shall  put  àR,  ôR',  for  the  remaining  parts 
of  the  same  quantities  of  the  order  mP,  &lc.,  and  we  shall  have 

R={R)-\-5R,  R'={R')~\-6R'.  [4008i] 

If  we  also  put   [(.2)  +  (^)  .cos.(5?i'<-2n^-|-/)]   for  the  part  of  .^+Z:cos.(5n'i;— 2n<+/),     [4008J] 
which  is  independent  of  m,  m  ;    and  prefix  the  sign  <5  before  the  same  quantity,  to  denote 
the  remaining  part,  we  shall  have 

^  +  Z.cos.(5  7i'<  — 2«ï'  +  /)+  Q=[(.^)  +  (^).cos.(.5îi'^  — 2n<+/)] 

-\-&.\A-^K.cos.{biït  —  ^nt  +  I]+q. 

Substituting  [4008fc,  m]  in  [4008/(],  and  neglecting  the  terms  mtn'.fd5R,  nim'.fd' 5R', 
which  are  of  the  order  m^  ;  also  the  terms  M.mm.  Q,  because  the  integration  does 
not  introduce  the  divisor     5  ?i' — 2  7i,     we  get 

M.\mfd{R)-^m'.fd'{R')\-i-mm'.\fd{R)-^fd'{R')]-JrM.\mfd5R-Jrm'fd'ôR'l 

=M.mm'.[{A)  +  {K).cos.{5n't—2nt+I)]-JrM.mm'.S.{A-\-K.cos.{5n't—2nt-^l)]. 

Now  equating  separately  the  parts  of  this  equation,  which  are  of  the  order  m^,  and  those 
of  the  order  m?;  putting  also    M=^l    [-3709],  in  terms  of  the  order  m^  we  get 

M. \m. f  d{R) +m'.f  d' {R)\  =  M.  mm'.  [{A) -{-{K). COS.  {57i't  —  2nt-\-l)'];  [4008p] 

mm'.{fd{R)  +/d'  (R)  ]  +  m  ./d  6  R  +  m'./d'  ÔR'=mm'.5.\A  -^K.  cos.  (.5  n'  (  —  2  n  t+I)  | .     [4008?] 


14008m] 


[4008?»] 


[4006o] 


[4008r] 


If  we  neglect  the  terms  of  the  second  member  of  [400S»/],  or  in  other  words,  the  terms 
of  the  elliptical  value  of  X,  depending  on  the  two  arguments  zero  and  bn't  — 2nt,  we 
shall  have  the  following  expression  [4008s],  which  includes  all  the  arguments  except  these 
two  ;  and  is  accurate  both  as  it  regards  terms  of  the  third  order  of  the  masses  m,  m',  and 
of  the  third  order  relative  to  the  excentricities  and  inclinations, 

m  m'.\fd  {R)  +/d'  {R)  \  +  m.fd8R-{-  m'.fd'ôR  r=  0.  [4008s] 

Substituting  M=^  1  [4008o]  in  the  product  of  [4008p],  by  the  quantity  m',  we  get,  by 
neglecting  terms  of  the  two  forms  0  and  5n't — 2nt  [4008;-],  mm'fdR-^m'-.fd'R'^^O. 
Subtracting  this  from  [4008s],  we  obtain 

m.fdiR-{-  m'./d'  Ô  R' -{- {m  —  m')  .  m'./d'  R'  =  0.  [4008«] 

VOL.  III.  39 


[4008<] 


154  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

the  corresponding  inequality  of  Jupiter.*  If  we  increase  7it,  n't,  by  their 
great  inequalities  in  the  expression  [4007],  there  will  result  in  ii  a 
term  of  the  form,t 

[4009]  R  =  ±qH.  COS.  {i'  n't  —  i7it±{5  n't  —  2nt)  +  A±E). 


and  since     a'~  n  =  a'  '~  n'  =  1    [3866»] ,    neglecting  terms  of  the  order   m,    this   may  be 
put  under  the  following  form,  terms  of  the  order  in*  being  neglected, 

[4008t;]  m  «*  n.fdSR^  m'.  a'  ^  n'.fd'  5  i?'  +  (  m  —  m') .  m',  a'  ^  n'.fd'R'  =  0 . 

Now  if  we  put    ^,  ^',    for  the  great  inequalities  of  Jupiter  and  Saturn;  S^^,  S^^',  for  the 
[4008t)']     parts  of  i^,  ^',  depending  on    dôR,   d'SR';    or  in  other  words,  those  which  depend  on  the 
combinations   [4006m],    excluding  the  angles  zero   and      5  n't  —  2nt,      we  sliall  have, 
as  in  [.371 5Z,  m], 

[i008w]         S^^  =  3an.ffdt.d&R;      S^  ^'=3  a' n'.ffd  t  .d'5  R' ;      ?,'^3  a' n'.ffdt  .d'R 
lastfoT*^"    Now  multiplying  [4008?;],  by     3dt,    integrating  and  substituting  [4008 w],  we  get 

mula, 
which 

[4008.r]  m  /a  •  5,  ?  +  '«'  /«'•  'I  ■? '  +  (  »*  —  '»')  •  ™'-  /«'•  ■?  '  ^  0  5 

inctudoa 

terms  of      wMch  IS  the  last  formula  of  La  Place,  proposed  to  be  demonstrated  in  [4007^^  ;  and  the 

the  order 

trfi.  complete  values  of    (S,  ^ ,    (5^  ^     ought  to  satisfy  it  ;    so  that   if  one  of  these  quantities  be 

rifioR  1     accurately  computed,  the  other  may  be  deduced  from  it  ;  but  the  usefulness  of  the  theorem 

is  restricted  by  the  circumstance,  that  it  can  only  be  applied  to  the  results  obtained  from  all 
[4008z]     the  sensible  terms  of  this  kind,   taken  collectively;   or  to  all  the  terms  corresponding  ic 

each  of  the  six  factors     e',    e^  «',    e  e'^,    e'*,    ey^,    e' y^. 

*  (2525)    The  relation  between    R    and    5v   is   expressed    by  the  equation   [.37155]. 
A  particular  case  of  this  formula  is  considered  in  [3703,  3715],  in  wliich 

[4009a]  R  =  M.  cos.  (  m,t  +  K)     [3703,  371  Irf]  ; 


[40095] 


and  we  find,  by  mere  inspection,  that  the  third  and  fourth  terms  of   uv    [37155]  have,  as 
in  [3715A],  the   divisors   m^,  m^  ;    also  by  comparing  [3702,  371  If],  we   find,   that  the 
terms  of   hv  [37155],  depending  on    hr,   have  the  divisor    mf  —  ?t^,    or    ?;?,  ±h-      It  is 
[4009c]     easy  to  generalize  this  result,  as  in  [4010],  where    lUi^i' n' — in. 

t  (2526)  If  we  increase  n't  by  the  great  inequality  of  Saturn  [3891],  and  nt  by  that 
of  Jupiter  [3889],  the  angle  i'n!t  —  int,  which  occurs  in  [4007,  4008],  will  be 
increased  by  a  quantity,  which  we  shall  represent  by  p  ;  then  putting,  for  brevity, 


[4012a] 


Ts=bn!i  —  2nt-\-b  e'—2i;  —  i'H'.  cos.A'—iU.  cos.^=  2f/  .cos.c  ; 

—  i'H'.sin.J'— 2'il.sin.^=2^.sin.  c;     5  e'  — 2  s -f  c  =  £. 


[4011] 
[4012] 

[4012'] 


VI.  H.  §  17.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        155 

Now  tlic  series  of  operations,  which  connects  H  and  L,  gives  to  the  parts 
of  //  the  divisors  (/'n' — inf,  i' n' — in,  i' n' — in±n  [40096,  c]  ;  [4010] 
and  the  same  series  of  operations  gives  to  the  inequalities  corresponding 
to  the  parts  of  R  [4009],  the  divisors*  [i' n' — in±:(5n' — 2n)}-, 
i'n'—inzt(5)i'  —  2n),  i' n'—in±  {bn' —  2n)  ±n.  If  i'n'—i7i 
or  i' n' — inztn  be  not  small  quantities  of  the  order  5n'  —  2n,  we 
may  neglect  5  n' — 2n  in  these  divisors,!  and  then  the  inequality, 
corresponding  to 

R=  ±qH.  cos.  [i' n' t  —  int±(5n't  —  2nt)  +  A^E},  [4013] 

will  be 

ÔV  =  ±qL  .  sin.  { i'  n'  t  —  i  n  t  ±  (5  n'  t  —  2  7it)  -^  B  ±El  ;  [4014] 


we  get,  successively, 

p  =  —i'H'.  sin.  ( n  +  ^')  —  i H-  sin.  {T,  +  ^)  [40126] 

=  —  i'  H'.\sm.  Tj  .  COS.  J'+  COS.  T^  .  sm.Â'1—i  H.  |sin.  T^ .  cos.  7l  +  cos.  Tg .  sln.^| 

=       2«j'.{sin.T5.cos.c-[-cos.T5.sin.c^^25'.sin.(T5-j-<^)  =  2q.sm.[bn't — 'ilnt-\-E).      [4012c] 

If  we  increase  the  angle    i' n' t — int-{-Jl    [4007]  by  the  quantity  p  ;   then  develop  the 
expression  by  means  of  [61]  Int.,  we  shall  obtain  an  additional  term  of  the  order  p,  and 
represented   by      — p  H  .s\n.  {i'  7i't  —  int-\-A).       Substituting   in   this    the    value   of    [4012«i] 
p  [4012c],  and  then  reducing  by   [17]  Int.,  it  becomes,  as  in  [4009], 

qH.cos.{in't  —  int-{-{57i't—2nt)-j-A-\-E]—qH.cos.\i'n't—int  —  {5n't—27ii)-\-A—E\.     [4012e] 

*  (2.527)    The  coefficient  of  t,  in  [4007],  is      i' 7i'  —  in,      and  from  this  arise  the 
divisors  [4010]  ;    but  in  the  term  [4009],  this  coefficient  is  augmented  by  the  quantity 
±(5  7i' — 2)t);    which  requires  a  corresponding  increase  in  the  resulting  divisors  [4010];     [4014o] 
by  this  means  the  divisors  [4010],  depending  upon  the   term  [4007],  change  into  those 
given  in  [4012].       If  we   suppose      5  7i' —  2  ?i      to  be   very   small,   in   comparison  with     [40146] 
i' 7i' — t?t     or     i' 7i' — in  ±71,     we  may  neglect  it  ;      and  then  the  chain  of  operations 
connecting  H,  L  [4007,4003],  will  have  the  same  divisors  as  that  connecting   q  H,  q  L      [4014c] 
[4013,  4014].      Now   [4007]    is   changed   into    [4013],    by  multiplying    by    ±  ?,     and 
augmenting  the  angle     i'n't  —  int     by     ±{57i't — 2  7it)zizE.      Applying   the  same     [4014rf] 
process   of   derivation   to    [4008],    we    get   the   corresponding   inequality  of  Jupiter,    as 
in  [4014]. 


t  (2528)    In  restricting  the  formula   [4014]    to   the   terms   mentioned   in  [4006'],  we 

5,j' 271 

may  consider  the  part  which  is  neglected  in  [4012'],  as  of  an  order     ,     or  j\  of 

that  retained  [3818fr]  ;  so  that  the  error  of  the  terms  ôv  [4014]  is  of  the  order  ^^qL; 


156  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

which  is  the  same  as  to  increase    nt,  n't,    by  the  great  inequalities  in  the 
term  of    àv  [4008].* 

We  must  also  increase,  in  the  terms  depending  on  the  first  power  of  the 
excentricities,    the  quantities    e,    e',   -us,    ra',    by   their  variations,  depending 
[4016]     upon  the  angle     bii!t  —  2?i  i  ;     but  it  is  evident,  that  this  will  not  produce 
any  sensible  inequalities.! 

18.   The  coefficients  of  the  inequalities  of  the  planets  vary  on  account  of  the 

Manner  of  ^       ^  n      i      *  t  '  •  i  •        •  i 

ihflffirA    secular  variations  of  the  elements  of  their  orbits  :  we  may  notice  this  in  the 
secular      followinq  manner.       We  must  first  put  the  inequality  relative  to  any  angle 

variations  *■ 

^lemans.     *'  *^'  t—  i^t,     undcr  the  form  t 

[4017]  P.  sin.  (i' n't  —  int  +  i't — is)-\-P'.  cos.  (i' 7i' t  —  in  t  +  i' s' — is). 


and  as  rj  is  of  the  order  ^p  [4012c],  it  becomes  of  the  order  ^l^p  L.  Now  the  great 
[40156]    inequalities  of  Jupiter  and  Saturn  being  nearly  1265', — 2957',  [44.34,  4474],  the  quantity 

2)  [4012ff]  becomes  —  5  X  2957'—  -3  X  1265'  =  —  18580%  or  about  y^-  of  the  radius  ; 
r4015c]     consequently  the  quantity  -j-^^pL     is  less  than    tïs  ^  tV -^'    °''  ^^^^  than  y J^ij  L  ;    and 

the  error  of  this  computation  of  i5  y  [4014],   arising  from  this  source,  will  generally  be  less 

than  ■j^jjjy  of  the  inequality  [4008],  which  is  under  consideration. 

*  (2528«)    If  we   increase    n'i,  nt,    by  the   great  inequalities,   using   j;  [4012J],  the 

expression  6  v  [4008]  will  become     S  v  z=  L  .  sin.  [i'  n't  —  i  ni  -{-B  ~\- p).      Developing 

[40]5(/]    this  as  in  [60]  Int.,    we  get    ôv  =  L.sm.{{'n't — i nt ~{- B) -j-jiL. cos.  [i' n't — int-j-B). 

Substituting  j}  [4012c],  and  reducing  by  [19]  Int.,  it  becomes  equal  to  the  sum  of  the 

two  expressions  [4008,  4014]. 

t  (2529)    The  smallness  of  these  terms  may  be  seen,  by  a  rough  examination  of  the 
increment  of  the  value  of  R  [1011],  arising  from  the  introduction  of  the  part  of   c  oi  ô  e 

[4016a]    [1286],  when  we  put     ?:'==5,     z  =  2,     a=l,  "       :=  74    [3818f/],     m'=^-J^^, 

e  =  0,05  [4061rf,  4080]  ;    observing  that  as    i'  —  i==:  3,    ^-  [1281'],  may  be  considered  as 

of  the  order  e^  and    (~)     of  the  order  e^  ;    so  that   5e  [1286]   may  be  considered  as  of 


[40106] 


[4017a] 


the  order  74  m'.  e^.  cos.  (5  n'< — 2nt-\-A},  or  ^i^  c  .  cos.  (5  ?i'i — 2nt-\-J)  nearly. 
Consequently  this  increment  of  e  produces  terms  of  the  order  y^i^,  in  comparison  with 
those  depending  on  e,  in  [4392],  none  of  which  amount  to  200';  hence  it  is  evidenti 
that  these  terms  are  insensible. 

X  (2530)    The  form  assumed  in  [4017]  has  been  frequently  used,  as,  for  example, 
in  [371  li]. 


Vl.ii.-^IS.]   DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.         157 

We  must  determine  the  values  of  P,   P\    for  the  epoch  1750,  and  then  put 

tang. A  =  ^  ■■,  L  =  ^/W+pr^ ;  [4018] 

the  sign  of    sin.  A     is  the  same  as  that  of    P',    and   its  cosine  is  the  same     [4018] 
sign  as  that  of  P   [401 9f?]  ;  then  the  proposed  inequality  will  be* 

L  .  sin.  {i'n'  t  —  int^  i'  /—  i  s  +  J) .  [40i9] 

We  must  determine  the  values  of  P,  P',  for  1950,  noticing  the  secular 
variations  of  the  elements  of  the  orbits  ;  and  we  shall  have  for  this 
inequality,  in  1950, 

(L  +  <5 L )  .  sin.  (i'n't—i nt  +  i'e  —  is-\-A  +  6A).  [4020] 

If  we  denote  by  t  the  number  of  Julian  years  elapsed  since  1750,  the 
preceding  inequality  relative  to  the  time  t  will  assume  the  following  form,t 


Çl  +  ^-^^  .  sin.  U'n't  —  int  +  i'  s'—  i  t  -\-A  + 


200 


[4021] 


Under  this  form  it  may  be  used  for  several  centuries  before  and  after  1 750. 
But  this  calculation  is  not  necessary  except  with  those  inequalities  which 
are  quite  large. 

In  the  two  great  inequalities  of  Jupiter  and  Saturn,  it  will  be  useful  to 
continue  the   approximation  as  far  as  the  square  of  the   time,   in  the  part 


[4021'] 


*  (2531)    Using,  for  brevity,    i'71't — int-\-i's'  —  ie=^Tg;    then  developing  [4019]     r^Q^g^-, 
by  means  of  [21]  Int.,  and  putting  the  expressions  [4017,  4019]  equal   to  each  other, 
we  get,  identically, 
P.  sm.  Tg  +  P'.  COS.  Tg  =  L.  sin.  {Tg-^A)=L.  cos.  A  .  sin.  Tg  +  L.  sm.A.  cos.  Tg.        [40196] 

Comparing  the  coefficients  of     sin.  Tg,     cos.  Tg,     separately,  in  both  members,  we  get 
P  =  L.cos.Jl,     P'=Z,.  sin. ^.      Dividing  the  second  by  the  first,  also  taking  the  sum     [4019c] 
of  their  squares,  we   get    [4018].      The   quantity   L   being   considered   as   positive,    we     [4019(f) 
get,  from  [4019c],  the  signs  of   sin.  A,  cos.  A,    as  in  [4018]. 

t  (2532)    If   5L,   &A,    represent  the  variations  of   L,    A,    in  200  years,   between 

i.bl.      t.SA 
1750  and  1950;   then  their  variations  in    t    years  will  be  represented  by      "^^j     '2ÔÔ  '     '■    ^^^ 

respectively.      Substituting  these  in  [4020],  it  becomes  as  in  [4021]. 

VOL.  III.  40 


158 


PERTURBATIONS  OF  THE  PLANETS, 


[Méc.  Cél. 


[4022] 


[4022'] 


Great  in- 
equality 
of  Jupiter, 

reduced  to 
a  tabular 
form. 


which  has  the  divisor    {bn! — 2nf.       This  part  of  the   expression  of   àv 
is  as  in  [3844], 


\aP'- 


2a. dP 


Sa.ddP' 


ûv  = 


6  m'.  n~ 


[5n'-2n).dt       (5n'— 2n)2.rf(2 


'.sm.{5>i't—2ntJ^5i  —  2s) 


{5n'—27if 


— ^aP- 


(OJI' 


2a. dP'  3a.ddP      } 

:—2n).dt       (an—2n)-.dl^^  ^  ' 


the  values  of  P,  P',  and  of  their  differentials,  being  relative  to  any  time 
whatever  /.  By  developing  them  in  series,  ascending  according  to  the 
powers  of  the  time,  and  retaining  only  the  second  power,  and  the  first  and 
second  differentials  of    P,   P',  the    preceding  quantity  will  become* 


[4023]       5i,  =  - 


6  ml,  rP' 


(5n'-2n)2 


2a. dP 


Sa.ddP' 


(5n'—2n).dt      {5n'—2nf.dt^ 
(      dP'    ,      Oa.ddP     7   ,  ,    ,       aap,>.^in.{5n't-2nt+5^-2s) 


I       dt   ^  (5n' 
2a. dP' 


;-2H).dri\'- 


i).dl-i) 
Sa.ddP 


{5n'—27i).dt       (5n'—2n)KdtZ 
,      C      dP  2a.ddP'    )   ,    ,  , 

'      I        dt        {5n'~2n).dt^^~ - 


dfi 


ddP\ 

dt^ 


>.cos.(5re'<— 2n<+5s'— 2s) 


*  (2533)  The  values  of  P,  P',  and  their  difFerentials  [4022],  must  be  computed  for 
the  particular  time  t,  for  which  the  value  o(  5v  is  wanted  ;  but  this  is  an  inconvenient 
method;  therefore  the  functions  by  which  sin.Tj,  cos.Ts  [3842a],  are  multipHed  in  [4022], 
[4022al  ^''^  developed  in  [4023]  in  series,  ascending  according  to  the  powers  of  t.  This  is  done 
by  means  of  the  formula  [oS50«],  neglecting  i^,  and  the  higher  powers  of  t.  Thus, 
if  we  put  the  factor  of  sin.  Tj,  included  between  the  braces  in  the  first  line  of  [4022], 
equal  to  u,  and  take  its  first  and  second  differentials,  neglecting  the  differentials  of  the 
third  and  higher  orders  ;  we  shall  get  the  following  values  of  U,  and  its  differentials  ;  in 
which  the  terms  in  the  second  members  correspond  to  the  epoch    <  =  0  ; 


[40326] 


[4022c] 


[4022d] 


U  =  aP' 


2a. dP 


Sa.ddP' 


/dt 
\d 


dU 
T 


(5n'-2n).dt       (5n'-2n)2.rf<a  ' 
dP'  2a.ddP  /ddU\       a.ddP' 


dt 


'  (5n'-2  7i).dV2' 


/ddU\ 


dfi 


Substituting  these  in  [3850a],  we  get  for  u,  the  same  expression  as  the  factor  of  sin.  Tj, 
in  the  first  and  second  lines  of  [4023].  In  the  same  manner,  the  factor  of  cos.  T^,  in 
the  second  line  of  [4022],  produces  the  corresponding  factor,  in  the  third  and  fourth 
lines  of  [4023]. 


VI.  il.  §  IS.]    DEPENDING  ON  THE  SQUARE  OF  THE  DISTURBING  FORCE.        159 

The  values  of  P,  P',  and  their  differaitials,  correspond  to  the  epoch 
of  1750,  and  are  determined  by  the  method  in  [3850,  &c.]  ;  the  other  parts 
of  the  great  inequality  of  m  being  rather  small,  it  will  be  sufficient,  by 
what  has  aheady  been  shown,  to  notice  the  first  power  of  the  time.  This 
great  inequality  will  then  have  the  folloAving  form, 


[4024] 


ôv=      (A  +5  t  +  Ct^).  sin.  (5n't  —  2nt  +  5  s'— 20 
+  (A'+B't  +  C't")  .  cos.  (5n't  —  2nt  +  5  /—  2  0 . 

We  may  also  put  the  great  inequality  of  m'  under  the  same  form,  by  which 
means  it  will  be  easy  to  reduce  these  inequalities  into  tables. 

If  ice  wish  to  reduce  the  preceding  inequality  to  one  term,  loe  must  calculate 
it  for  the  three  epochs  1750,  2250,  2750.      Let 

f3  .  sin.  (5n't  — 2nt  + 5  b'— 2s  + a)  [4025] 

be  this  inequality  in  the  year  1750;  and  |3^,  a,;  (3,,  a„,  the  values  of  p,  a  [4025] 
at  the  epochs  2250,  2750  ;  then  the  inequality  corresponding  to  any  fquaiuyof 
time  whatever  t,  will  be*  reduced 


/  ds   ,    -,    „  ddP;\      .      ^_    ,         _         ,    ,~  ,      ^      .         .        dA    ,    ,    „  ddA  ) 

the  differentials   p   and  a  correspond  to  the  epoch  in  1750;    and  we  shall 
have,  by  [3854— 3856], f 


to  one 
term. 


[4026] 


d^       4  3,— .3(3  — p,,^ 
dt                 1000          ' 

dd^        p„— 2(3,+  3_ 
dt^              250000       ' 

[4027] 

d\       4  a,— 3  a  — A„  , 
dt  ~           1000 

dd\        A„  — 2a,  +  a 
dt^  ~       250000 

[4027'] 

*  (2534)    p  and  A  being  functions  of  t, 

we  shall  have,  as  in   [3850«], 

e4-t   '^^^^t^  '^'^^ 

and 

A  _i_y    ^^  J^ii2  '^'^^ 

[4025a] 

for  their  values  ;   using  for    p,  A,    and  their  differentials,  the  values  corresponding  to  the 
epoch  in  1750.      Substituting  these  in  [4025],  it  becomes  as  in  [4026]. 

t  (2535)    If  in  the  general   formulas    [3854—3856],   we  change    P,    P,,    P„,    into 
|8,   3,,    p„,     the   expression  [3854]  will  become  like  the  first  of  the   functions  [4025a]  ;    [4027o] 

J    ,  ,  .  ,  d  13        ddp 

and    by  making  the   same  changes  in  [3856],  we  shall  get  the  values   of      — ,       — 


160  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

In  conformity  to  the   remark   we   have  made   in  [3720],   these   two  great 
[4027"]    inequalities  of  Jupiter  and    Saturn  must   be  applied  respectively  to  their 
mean  motions. 


[4027].      In  like  manner,  by  changing,  in  [3854—3856],    P,  P,,  P„,    into    A,  A,,  A„, 
the  formula  [3854]  will  become  as  in  the  second  of  the  functions  [4025a],  and  [3856] 

[4027c]    will  give  the  values  of      —,    — -    [4027']. 


VI.iii.§18']    DEPENDING  ON  THE  OBLATENESS  OF  THE  SUN. 


161 


CHAPTER   III. 


PERTURBATIONS  DEPENDING  ON  THE  ELLIPTICITY  OF  THE  SUN. 


18'.  Since  the  sun  is  endowed  with  a  rotatory  motion,  its  figure  will 
not  be  perfectly  spherical.  We  shall  now  investigate  the  effect  of  its 
ellipticity  on  the  motions  of  the  planets  ;  putting 

p  =  the  ellipticity  of  the  sun,  expressed  in  parts  of  its  radius  ; 
q  =  the  ratio  of  the  centrifugal  force  to  the  gravity  at  the  sun's  equator  ; 
(X  =  the  sine  of  the  planet's  declination  relative  to  the  sun's  equator  ; 
D  =  the  sun's  semi-diameter  ; 
1  =  the  sun's  mass,  usually  called  M  ; 


R  =  {?-\fi)-^'i^'-\)' 


Symbols. 


[4028] 


then  it  will   follow,  from    [1812],    that  the  sun's   ellipticity  adds   to  the    vaiuoof 
function  R  [913],  the  quantity*  dependine 


on  the 
ellipticity. 

[4029] 


*  (2536)  We  shall  suppose  m',  m",  ??i"',  &c.  to  represent  the  particles  of  the  sun's 
mass  ;  considering  it  as  being  composed  of  concentrical  elliptical  strata  of  variable  densities, 
symmetrically  arranged  about  its  centre  of  gravity,   taken  as  the  origin  of  the  co-ordinates 


of  these  particles  x',  y' ,  £  ;    x",  y" 


&ic.      The  co-ordinates  of  the  attracted  planet  m 


being  represented  by  x,  y,  z,   and  its  distance  from  the  sun     7-=\/(.r^-j- )/^-f-c^).      In 

this  case,  the  expression  of  R  [91.3]  will  be  reduced  to  its  last  temi    7?=  —  —  ; 
{xx'+yy'+zz') 


any  term  of  the  form 


because 
depending  on  the  particle  m',  whose  co-ordinates 


are    x',  y',  s^,    is  destroyed  by  a  similar  term,  depending  on  an  equal  particle  m',  whose 
co-ordinates  are    — x',    — y',    — 2'.      Substituting,  in  [4029è],  the  value  of  X  [914], 

VOL.  III.  41 


[4029a] 


[40296] 


[4029c] 


162  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

[4030]  If  we  notice  only  this  part  of  R,  and  put  fdR  =  g-^R;  g  being  a 
constant  quantity  ;  we  shall  find,  that  the  differential  equation  in  r  6r 
[926,  928']  becomes,  by  neglecting*  the  square  of  tJ., 

[4031]  0=-^^^  +  -^^— +  2^+^ ^ .t 


neglecting  terms  of  the  order    m' m",    and  using  the  sign  /  to  represent  the  sum  of  the 

[4029dl    terms  depending  on  all   the  particles,  we  get      iî  =  —  C'TTr', ,„  ,  ,  , ,„  ,  ,  , —. 

This  expression  of  R  corresponds  to  that  of  —  V  in  [1385"',  1386],  m'  being  the  attracting 
particle,  and  \/ \ {x' —  a,)^ -\-  {y —  y)^  -{-  {z'  —  z)^ }  its  distance  from  the  attracted  planet  ; 
hence     iî  =  —  V;     and  by  substituting  the  value  of   V  [1812],  we  get 

[4029e]  -«  —  —,.—  ra  •JU.[iJ.       s). 

The  last  term  being  multiplied  by    D^,    to  render  it  homogeneous  with  the  first,  because 

in  [1812,  1795"],  the   semi-diameter  of  the  body  M  is  put  equal  to  unity,  and  here  it  is 

[4029/]    supposed  to  be  D.      Again,  by  comparing   [1670',  4028],    we  get     a.(p  =  q;     also   by 

comparing  [1801,  &lc.,  4028],  we  get    o.h  =  p.      Substituting  these  in  [40296],  we  obtam 

[4029^]  -^7 r3  -M-ii^—s). 

Now  if  the    sun  were    of  a  spherical   form,    with  no   rotatory  motion,    we  should  have 

M 
[4029A]     P  =  0,    7^0,     and  then    J?  =  —  —   [4209^].      Subtracting  this  from  the  general  value 

of  R  [4029^'-],  we  get  the  part  of  it  depending  on  the  sun's  ellipticity,  namely, 
[4029i]  R^_^Illl^t^.M.ii^^—^), 

and  by  putting,  as  in  [4028],  the  sun's  mass    Jlf  =  1,    it  becomes  as  in  [4029]. 

*  (2537)    The  inclination  of  the  sun's  equator  to  the  ecliptic  is  less  than  8'^,  and  its  sine 
[4030a]    j^  ^g^^jy  ^^   g^   ^j^^j   ^2   „-j„st   be  less  than  {if,   or  ^3-;    which  may  be  neglected    in 

[4030t]     comparison  with  ^  5  and  then  [4029]  becomes     R  =  —  ^.(P  —  s?)-"^- 


t  (2538)    Substituting,  in   [926],  the  value  of    rPt'=r.  (— )    [928'],  also    i^=n^a^ 

,-100],  we  get 

d2.(,v5r)    ,    ,fia?.rSr    ,    „^,„    t  /dR\ 

[40316]  0=-±^  +  ^^~  +  2fàR  +  r.(jy). 


[4031a] 

^         ^     [3700],  we  get 


Now  the  value  of   R  [4030&],  depending  on  the  sun's  ellipticity,  gives 

[4031c]  fdR^-i.{?-hq)-D'-fà.'^-  =  -h{p-ii)-^+g;  '••C^)=(''-*?)-Tr^ 


VI.iii.§lS'.]    DEPENDING  ON  THE  OBLATENESS  OF  THE  SUN.        163 

To  determine  the  constant  quantity  g,   we  shall  observe,  that  the  formula 
[931]  gives,  in    àv,    the  quantity* 

3a.ngt  +  {^  —  h(])  '  —  .lit;  [4032] 


a' 


n  t    denoting  the  mean  motion  of  the  planet  ;  this  quantity  must  be  equal 
to  zero  ;   therefore  we  have 


ST  =  ^ ^ . 

^  3  «3 


Hence   the  differential  equation   in    r&r    becomes,  by  neglecting  the  square 
of  c,  and  observing  that    n-a'^^=\    [3709']  ,t 

+  ^l^Mï  ,  n~.  Z)-.  { 1  +  3  e  .  COS.  (n  t  +  i  —  ^)]. 


but  from  [4031c],  we  get 

a?' 


3a/diî  +  2ar.(^)==3«i^  +  (p-Aî).^  =  3«^  +  (p-H)' 


[4032'] 
[4033] 
[4033'] 

[4034] 


substituting  tliese  in  [40316J,  we  get  [4031].     We  may  observe,  that  the  symbol  (J-  [4031a] 
is  entirely  different  from  that  in  [4028]. 

*  (2539)    The  constant  quantity  g  is  to  he  found,  as  in  note  699,  Vol.  I,  page  550,  by 

putting  the  terms  of  [931],  multiplied  by  t,   or  rather  by     ^oZT^)'     equal  to  nothing. 

These  terms  are  evidently  produced  by  the  two  last  terms  of  [931], 

3  afn  dt.fdR  +  2afndt.r.  0^^  ;  [4032a] 


[40326] 


noticing  merely  the  term  a  of  the  value  of  r,  which  is  evidently  the  only  part  which  affects 

the  coefficient  of  t,   now  under  consideration.      Multiplying  this  last  expression  by    ndt, 

and  integrating,  it  becomes  as  in  [4032],  which  represents  the  part  of   ô  v,   connected  with      [4032c] 

the  factor  t.      Putting  this  equal  to  nothing,  we  get  [4033]. 

t  (2540)    We   have      r  =  a.\l—e.  cos.  (  n  <  +  s  —  w  ) }      [3747],      neglecting    e^  ;     ^^^g^^,^ 
hence  we  get,  by  using  [4033'], 

i  =  1  .n  +  3  e  .  cos.  (ni4-s  —  zi)\=^nm  +  3e.  cos.  (n  t  +  t—z,)];  [4034i] 

substituting  this,  and  g  [4033],  in  [4031],  we  get  [4034]. 


164  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 

This  gives,  by  integration,* 
[4035]  ^  =  i.(p  —  19).^.^  —  3e.«^.sin.(«<  +  f  —  «)}. 

The  elliptical  part  of     -     is     1  —  2  e  .  cos.  (nt  +  s  —  zi)     [3876a]  ;      and 
if  we  suppose  w  to  vary  by    6^^,    we  shall  have   [3876f/],t 

[4036]  -g- =r — eô'a .  sin.  (nt-{- s  —  w). 


*  (2541)    This  integration  is  made  as  in  [865 — 871"],  putting    rSr^^y';    hence  [4034] 
becomes,  by  connecting  together  the  terms  depending  on  e, 

[4035a]    o  =  ^+n^.y'—i.{p—hq)-n^-D^+\n^y'-\-i.{p—iq).7v'-D^.3e.cos.{nt-\-e—:;!). 

[40356]    Putting    y'^y-]-^.(p — ^q).D'^,    and  neglecting  the  term  of  the  order  ye,  or  e^,  we  get 

[4035c]  0  =  -j^l^  n^  y  +  2  .  {f  ~i  q)  .  71^.  D^.  e  .COS.  {n  t  -\-  s  —  zi); 

[4035rf]    which  is  of  the  same  form  as  [865a,  870',  871'],  changing  a  or  m  into  n,    s  into   s  —  w, 
a -fir    into    2.(p — ^q)n^.  D~.e,     and  then  [871"]  becomes 

y  =  —  ^ —  .sin.(?t  <  +  £  —  «)  =  — (p  —  iq)  -711  .D^.e  .sin.  Çnt-\-e  —  to)  ; 

substituting  this  in    y'    or    rSr   [4035i],  we  get 
[4035e]  r5r  =  i.(p  — i<?).D2  — (p  — iy).ni.I32.e.sin.  (n^-|-£  — to); 

dividing  this  by  «^,  we  obtain  [4035].  We  may  remark,  that  the  term  of  the  form 
air.  cos.  {nf-{-i  —  to)  [871'J  is  included  in  the  elliptical  motion,  and  it  is  not  necessary 
to  notice  this  term  in  the  present  calculation. 

V  Ô  r 
■f  (2542)    Comparing  together  the  expressions  of    — j-    [3876^,  4035],  we  find,  that 

if  the  coefficients  of    sin.  (7it-\-s  —  to)     be  put  equal  to  each  other,  we  shall  get 

D- 

[4036a]  —  e  ^5  TO  =  i  .  (  p—  i  Ç  ) .  —  .  (  —  3e  .7it); 

whence  we  obtain   'îis,   as  in  the  first  equation  [4037].      The  second  expression  [4037]  is 

deduced    from  the   first   by   the  substitution   of     n  =  a     ^    [3709'].       Again,  since  the 

formula  [4035]    does  not  contain  a  term   depending  on      n  t .  cos.  {71  i -\- e — to),      and 

[4036c]     in  [3876]  this  cosine  is  connected  with  the  factor    ôe,    we  shall  have   (îe  =  0.      The 


VI.iii.§18'.]    DEPENDING  ON  THE  OBLATENESS  OF  THE  SUN.        166 


If  we  compare  this  expression  of     %-     with  the  preceding,  we  shall  obtain    ^^^  ,^^ 

""  of  the 

perihelion  f 
rjo  T)-   f  arising 

6^=.(p_i9).^.nï  =  (p-è7).-^     [4036«,6];  [4037] 

W  ^  from  the 

Ct  oblateneai 

of  Ihe 

3UU,  is 

therefore  the  most  sensible  effect  of  the  ellipticity  of  the  sun,  upon  the  motion    '"«nsibie. 
of  a  planet  in  its  orbit,  is  a  direct  motion  in  its  perihelion  ;   but  this  motion    [4037'] 
being  in  the  inverse  ratio  of  the  square  root  of  the  seventh  power  of  the 
greater  axis  of  the  planetary  ellipsis,  îve  see  that  it  cannot  be  sensible  except     [4038] 
in  Mercury  [4036/], 

To  find  the  effect  of  the  sun^s  ellipticity  upon  the  position  of  the  orbit, 
we  shall  resume  the  third  of  the  equations  [915].  This  equation  may  be 
put  under  the  following  form,* 

d,lz       n^a^.z   ,    f(lR\ 
^^dr-^-^  +  yiû)'  f4039] 

2:2 

We  shall  take  the  solar  equator  for  the  fixed  plane,  which  gives      n^=  — ^      [4039'] 
[4040fl]  ;  then  by  observing  that    r  =  x^  +  ^/^+z',    we  shall  havef 

— j  =  3.(p  — i9).-^^5— .3;  [4040] 

constant  part  of    —3- ,     which  is  nearly  equal  to  that  of    — ,     is  represented  in  the  present 
case  by  the  first  term  of  the  second  member  of  [4035]  ;  so  that  we  shall  have 

'i^i.{9-iq).^,  [4036^] 

as  in  [4042].      Now  we  shall  see,  in  [4262 — 4265'],  that  if  the  sun  be  homogeneous, 

we  shall  have,  for  the  orbit  of  the  planet  Mercury,     5j3  =  (p — ^q) .  — .<=0',012.?  nearly     [4036c] 

[4265]  ;  and  this  expression  is  much  smaller  for  the  other  planets,  on  account  of  4he  divisor  a^  ; 

so  that  it  produces  only  12°"  in  a  thousand  years  for  Mercury,  and  is  much  less  for  the  other     [4036/"] 

planets.     The  quantity   5  r  [4036'/,  4260 — 4263]  is  evidendy  insensible. 

*  (2543)    Substituting      i>.^n^  a^    [3700]    in    the   third    equation    [915],    it   becomes     [4039a] 
as  in  [4039]. 

t  (2544)    In  [4028],  (a  is  put  for  the  sine  of  the  planet's  declination  above  the  plane     [403951 
of  the  sun's  equator,  its  perpendicular  distance  above  this  plane  being  z,  and  its  distance 

VOL.  III.  42 


166  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 


[4041] 


hence  the  preceding  differential  equation  becomes* 

dch 


now  by  what  precedes  [4036f/],  we  have 


[4042]  ^=i.(p-ly).^^; 

hence  we  obtain 
[4043]  0  =  ^"  +  n^..|l+2.(p-ic).^'|. 

This  gives,  by  integration, f 

[4044]  z  =  ip  .sin.  <nt .  (1  + (p  —  I  q)  •  ~^  )  —  4? 

[4045]     -    being  the  inclination  of  the  orbit  to  the  solar  equator,!   and  d  an  arbitrary 

z 
[4040o]    from  the  sun's  centre  r;    hence  we  evidently  have     (a^-;     also     r  =  y/(x^ -j- y^ 4" ~^) 

[914'].      Substituting  this  value  of  fA  in  [4029],  we  get 

[4040i]  ij_(p_iç).D2.^E:__L^. 

/  d  r\        z 
Taking  its  partial  differential  relatively  to  z,  neglecting  z^,  and  observing  that     i—]=-, 

we  get 
[4040c]  (^)  =  (p-i<?).i3^.^?|  +  i^  =  3.(p-i<?).f.z. 

1  1    _  7l2 

î"5  «5  o2 


1  1         n~ 

Retaining  only  the  constant  part  of  r,  we  may  put     -  =  —  =  — -    [3709'],  and  then  the 


preceding  expression  [4040c]  becomes  as  in  [4040]. 

*  (2545)    Noticing  only  the  terms  of  r,  depending  on  the  sun's  ellipticity,  we  may  put, 

[4041a]     as  in  [4036c/] ,     r=za-j-5r,     whence    -==-.n '^j.     Substituting  this  and  [4040] 

in  [4039],  we  get  [4041]  ;  and  if  we  use  [4036(^],  it  becomes  as  in  [4043]. 

t  (2546)    Comparing  [865',  4043],  we  get     y  =  z,     a  =  n  .U -j- {p  —  ^q)  .  —  ^, 

"     by  neglecting     (p  —  hlT-      Substituting  these  in  the  first  value  of  y  [864a];  changing 
also    b    into    <p,    and    (p   into    —  ê,    we  get  [4044]. 

X  (2547)    The  sine  of  the  declination  is  equal  to     -    [4040a],  and  its  greatest  value 

[4045a]    is   equal   to    -    [4044]     or     -     nearly  ;    which   evidently   represents    the   sine   of   the 

inclination  of  the  orbit  to  the  solar  equator. 


VI.  iii.  §  18'.]    DEPENDING  ON  THE  OBLATENESS  OF  THE  SUN.        167 


[4045'] 


[4046] 


constant  quantity.  Tims  the  nodes  of  the  orbit  on  this  equator  have  a 
retrograde  motion  equal  to  the  direct  motion  of  the  perihelion,  and  which 
cannot  therefore  be  sensible,  except  in  the  orbit  of  Mercury*  At  the  same 
time  ive  see  that  the  sun'' s  ellipticity  has  no  influence  on  the  excentricity  of  the 
planeCs  orbit  [4046f  ],  or  on  the  inclination  of  this  orbit  to  the  solar  equator  ; 
it  cannot  therefore  alter  the  stability  of  the  planetary  system. 

*  (2548)    It  is  evident  from  the  form  of  the  angle,  which  occurs  in  [4044],  that  the 

D- 

retrograde   motion   of  the  node    in  tJie  time    t    is  represented   by      nt .  {^  —  J?)--t7)     [4046a] 

because  the  body  is  in  the  node  wjien     c  =  0,     and  it  completes  its  revolution,  to  the 

same  node,  while  the  angle      nt  -{-nt  .{if — è  <p) . -5-      increases  by  360'';    the  mean     [40466] 

periodical  revolution  being  performed  in  the  time  t,  which  makes  nt  =  360''  [4032']. 
Hence  it  is  evident,  that  the  retrograde  motion  of  the  node  in  the  time  t  is  nearly  equal  to 
the  difference  of  these  quantities,  as  in  [4046a],  being  the  same  as  the  direct  motion  of  the 
perihelion  [4037].      As    (5e  =  0    [4036c],   the  excentricity  is  not  affected  by  the  sun's     [4046c] 

ellipticity,  neither  does  it  affect  the  inclination     -     of  the  planet's  orbit  to  the  sun's  equator 

[4045a],  which  is  constant,  because  ç  is  one  of  the  constant  quantities  obtained  by  integration. 

The  results  found  in  this  chapter  agree  with  those  found  by  Mr.  Plana    in  the  Memoirs 

of  the  Royal  Society  of  London,  Vol.  II,  page  344,  &c.,  noticing  the  term  neglected  by     [4046rfl 

La  Place  in  [4030]  ;  makmg  also  the  computation  directly  from  the  formulas  [5788—5791], 

and  carrying  on  the  approximation  to  a  rather  greater  degree  of  accuracy. 


168  PERTURBATIONS  OF  THE  PLANETS,  [Méc.  Cél. 


[4047] 


CHAPTER    IV. 

PERTURBATIONS  OF  THE  MOTIONS  OF  THE  PLANETS,  ARISING  FROM  THE  ACTION  OF  THEIR  SATELLITES. 

19.  The  theorems  of  ^10,  Book  II  [442",  &c.],  afford  a  simple  and 
accurate  method  of  ascertaining  the  perturbations  of  the  planets  from  tlie  action 
of  their  satellites.  We  have  seen,  in  [451',  &;c.],  that  the  common  centre 
of  gravity  of  the  planet  and  its  satellites,  describes  very  nearly  an  elliptical 
orbit  about  the  sun.  If  we  consider  this  common  orbit  as  the  ellipsis  of  the 
planet  ;  the  relative  position  of  the  satellites,  compared  with  each  other  and 
with  the  sun,  will  give  the  position  of  the  planet,  relative  to  this  common 
centre  of  gravity,  consequently  also  the  perturbations  which  the  planet  suffers 
from  its  satellites.     Let 

M^  the  mass  of  the  planet  ; 
Symbol..  Ji  :^  ^j^g  radlus  vector  of  the  common  orbit,  or  the  orbit  of  the  centre  of  gravity 

of  the  planet  and  satellites,  the  origin  being  the  sun's  centre  ; 
V  ==  the  angle  formed  by  the  radius  R,  and  the  invariable  line,  taken  in 

the  comm07i  orbit,  as  the  origin  of  the  longitudes  ; 
m,  ml,  &c.  the  masses  of  the  satellites  ; 
[4048]  r,    /■',   &c.  the  radii  vectores  of  the  satellites,  the  origin  being  the  common 

centre  of  gravity  of  the  planet  and  its  satellites  ; 
V,   v',   &c.  the  longitudes  of  the  satellites,  referred  to  this  common  centre  ; 
s,    s',    &c.  the   latitudes   of  the   satellites    above    the  common  orbit,    and 

viewed  from  the  common  centre  ; 
X,   Y,  Z  the  rectangular  co-ordinates  of  the  planet  ;   taking  the  common 

centre  of  gravity  of  the  planet  and  its  satellites  for  their  origin  ; 

the  radius  R  for  the  axis  of  X  ;  and  for  the  axis  of  Z  the  line 

perpendicular  to  the  plane  of  the  common  orbit. 


VI.iv.§19.]      ARISING  FROM  THE  ACTION  OF  THEIR  SATELLITES.  169 

We  shall  have  very  nearly,  from  the  properties  of  the  centre  of  gravity, 
and  by  observing  that  the  masses  of  the  satellites  are  very  small,  in 
comparison,  with  that  of  the  planet,* 

0  =  MX  +  mr.  cos.  (  v  —  f/)  +  m'  r'.  cos.  (v'  —U)  +  &c.  ; 
0=^MY-i-mr.  sin.  ( i'  —  C/)  +  m' r'.  sin.  {v'—U)  +  hc.\  [4050] 

0  =  M  Z  +  m  .  r  s  +  m',  r  s  +  &c. 

The  perturbation  of  the  radius  vector  is  nearly  equal  to  X;   consequently 

it  is  equal  to  Perturba- 


tions. 


.r.  cos.  Ct; — U) .r'.cosJv' — U)  —  &c.=:  Perturbation  of  radius  vector.     [4051] 


The  perturbation  of  the  motion  of  the  planet  in  longitude,  as  seen  from  the 

r 

R 

—  ^•-B-sin,(t; — U) — -  .  —  .sin.(v' — U)  —  &c.  =  Perturbation  in  longitude.     [4052] 

wU     -cCr  Jim.     JAj 


Y 

sun,  is  very  nearly    —  ;    therefore  it  is  equal  to 


m    r 


*  (2549)    If  we  let  fall  from  the  points  where  the  bodies  M,  in,  m',  &IC.  are  situated, 
perpendiculars  upon   the  axes  of    X,   Y,  Z,    the  distances  of  these  perpendiculars  from     [4050a] 
the  common  centre  of  gravity  of  the  planet  and  its  satellites,  taken  as  the  origin,  will  be, 
respectively,  as  follows; 

On  the  axis  of  X ;         X;         r  .  cos.  {v  —  U)  ;         ?•'.  cos.  {v' —  U),    &,c.  ;  [40506] 

On  the  axis  of  F;  Y  ;         r  .  sin.  {v—  U)  ;         r' .  sin.  {v  —  U),    &c.  ;  [4050c] 

On  the  axis  of  Z  ;         Z  ;         r  s  ;  r's',hc.    nearly.  [4050d] 

Multiplying  the  distances  [4050/^]  by  the  masses    M,  m,  m,  &c.  ;    and  taking  the  sum  of     [4050c] 
these  products,  it  will  become  equal  to  nothing,  by  means  of  the  first  of  the  equations  [124]  ; 
hence  we  get  the   first  of  the   equations   [4050].       In  like  manner,  by  multiplying  the 
distances,  measured  on  the  axis  of  Y,  by  M,  m,  m!,  &ic.,  respectively,  and  putting  the  sum     [4050/"] 
of  the  products  equal  to  nothing,  we  get  the  second  of  the  equations  [4050].      The  third  of 
these  equations   is    formed    by  a  similar  sum,   corresponding  to   the   axis  of  Z.      From 

Y       Z 

these  three  equations,  we  may  find  the  values  of    X,    —,     —,     as  in  [4051,4052,  4053]; 

and  as  the  radius  R,  or  axis  X,  passes  through  the  place  of  the  common  centre  of  gravity, 

Y      Z 

it  is  evident  that  these  quantities    X,    —,     —     will  represent,  respectively,  the  perturbations     [4050^] 

of  the  radius  vector,  of  the  longitude  and  of  the  latitude,  conformably  to  what  is  said  above. 
VOL.  III.  43 


170  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

Lastly,  the  perturbation  of  the  motion  of  the  planet  in  latitude,  as  seen  from 
the  sun,  is  very  nearly    -^  ;    hence  it  is  nearly  equal  to 

m     rs        m!    r' s'        c  -r»  i      •       •     i     •      i 

[4053]  ■ —  IT;  •  p^ M  '  ~R "^  Perturbation  m  latitude. 

These  different  perturbations  are  sensible  only  in  the  earth,  disturbed  by  the 
moon.  The  masses  of  Jujnter^s  satellites  are  very  small  in  comparison  with 
that  of  the  planet,  and  their  elongations,  seen  from  the  sun,  are  so  very 
[4054]  small,  that  these  perturbations  of  Jupiter  are  insensible.  There  is  every 
reason  to  believe  that  this  is  also  the  case  for  Saturn  and  Uranus. 


VI.  v.§-20.]  ELLIPTICAL  PART  OF  THE  RADIUS  VECTOR.  171 


CHAPTER  V. 

CONSIDERATIONS  ON  THE  ELLIPTICAI.  PART  OF  THE  RADIUS  VECTOR,  AND  ON  THE  MOTION  OF  A  PLANET. 

20.  We  have  determined,  in  [1017,  &c.],  the  arbitrary  constant 
quantities,  so  that  the  mean  motion  and  the  equation  of  the  centre  may 
not  be  changed  by  the  mutual  action  of  the  planets.      Now  we  have,   in 

the  elliptical  hypothesis,*     — y—  ==  **"5     ^^^^  ''^('-^^  of  the  sun  being  put  equal     [4055] 

to  unity.     Hence  we  obtain 

2. 

a  =  n      '  .  (1  +  X»i)  ;  [4056] 

for  the   semi-transverse  axis,    which  must   be    used    in  the    elliptical    part 
of  the  radius  vector. 

If  we  suppose,  in  conformity  to  the  principles  assumed  in  [4078 — 
4079,  &c.],  that 

«==n~*;  a'=n'~'\     &c.  ;  [4057] 

we  must  increase  a,  a',  &c.  in  the  calculation  of  the  elliptical  part  of  the 


•  (2550)    This  is  the  same  as   [3700],   putting,  as  in  [3709a],    iJ.  =  M-\-m,     and 
M^l,    as  in  [4055].      From  this  we  get 

a  =  7i'~^.(l-f  m)^  =  n~"^.(l  +  im  — T^V^^+^O;  [4056o] 

which,  by  neglectmg  terms  of  the  order  m^,  becomes  as  in  [4056]. 


172 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


[4058]      radius  vector  by  the  quantities    ^m  a, 


\  m  a. 


Stc.   respectively  ;  but  this 


Increment 
of  the 
radius 


augmentation  is  only  sensible  in  the  orbits  of  Jupiter  and  Saturn. 


*  (2551)  The  values  of  a",  ce',  for  Jupiter  and  Saturn  [4079],  are  respectively 
augmented  by  the  correction  [4058],  in  the  expressions  [4451,  4510].  The  similar 
augmentation,  corresponding  to  the  other  great  planet  Uranus,  is  |^m"o",  which,  by  using 


[4058a] 
[40586] 


?»''  [4061],  becomes 


If    this    quantity    were    an    arc    of    the    planet's    orbit, 


[4058c] 


[4058rf] 


58512 

perpe7i(Ucu1ar  to  the  radius  vector,  it  would  subtend  only  an  angle  of  3'~,6,  when  viewed 
from  the  sun  ;  but  being  in  the  direction  of  the  radius  vector,  it  produces  no  change  in  the 
longitude,  seen  from  the  sun  ;  or  from  the  earth,  when  the  planet  is  in  conjunction  or  in 
opposition.  The  most  favorable  situation  for  augmenting  the  effect  of  this  correction,  in 
the  geocentric  longitude  of  the  planet,  is  when  the  earth  is  nearly  at  its  greatest  angle 
of  elongation  from  the  sun,  as  seen  from  the  planet.      This  angle  for  the  planet  Uranus 

is  quite  small,  its  sine  being  represented  by    — ;  =  j^    nearly  [4079]  ;    and    as   the  above 

correction  3°",6  is  to  be  diminished  in  the  same  ratio,  it  produces  only  0'',2  for  the  greatest 
possible  effect  of  this  augmentation  of  the  radius,  in  changing  the  place  of  the  planet  Uranus, 
as  seen  from  the  earth  ;  consequently  this  correction  is  wholly  insensible. 


[4058e] 


We  have  already  observed  in  the  commentary  in  Vol.  I,  page  561,  that  Mr.  Plana 
makes  some  objections  to  the  introduction  of  the  constant  quantity^,  in  the  integral  [1012'], 
and  he  has  also  urged  similar  remarks  against  the  use  of  the  constant  quantities  _/),  f^ 
[1015'],  in  finding  the  integral  i5m  [1015]  ;  but  a  little  consideration  will  show,  that  these 
objections  do  not  apply  to  the  accuracy  of  the  results,  or  to  the  astronomical  tables  founded 
upon  them  ;  but  merely  to  the  most  convenient  way  of  ascertaining,  as  a  mere  matter  of 
curiosity,  the  orbit  a  body  would  describe  if  it  were  not  acted  upon  by  the  disturbing  force, 
or  of  computing  the  whole  effect  of  the  disturbing  force  in  a  given  time.  This  subject  has 
been  discussed  very  ably  by  Mr.  Poisson,  in  the  Connaissance  des  Terns  for  the  year  1831, 
[4058/"]  pag.  23 — 33  ;  and  we  shall,  in  the  remaining  part  of  this  note,  avail  ourselves  of  his  remarks. 
The  complete  integrals  of  the  three  differential  equations  [545],  which  determine  the 
co-ordinates  x,  y,  z,  of  the  planet  referred  to  the  sun's  centre  as  their  origin,  contain 
six  arbitrary  constant  quantities  [571«],  which  we  shall  denote  by  a,  h,  c,  Sec.  ;  and  the 
same  is  true  in  using  the  polar  co-ordinates  r,  v,  s;  as  we  have  already  seen,  in  [602"], 
in  the  Jirst  ajrproximation,  where  the  disturbing  forces  are  neglected,  and  the  simple  elliptical 
motion  obtained.  In  a  second  approximation,  in  which  we  notice  only  the  first  power 
of  the  disturbing  forces,  we  may  put  &r,  Sv,  5  s  for  the  increments  of  r,  v,  s  ;  and  then 
the  integrations  being  made,  as  in  [1015,  &:c.,  1021,  1030],  will  introduce  six  new  arbitrary 
constant  quantities,  a',  b',  d,  &;c.  ;  these  accented  letters  being  taken  for  symmetry,  instead 
0Î  g,  fi,  fl,  &.C.,  used  by  La  Place.  A  third  approximation  includes  terms  of  the  second 
order  of  the  disturbing  forces,  and  by  similar  integrations,  produces  six  other  constant 
quantities  o",  h" ,  c",  Sic,  and  so  on  successively.      If  ive  restrict  ourselves  to  the  second 


[4058g 


[4058;i] 


[4058i] 


VI.v.s^20.]  ELLIPTICAL  PART  OF  THE  RADIUS  VECTOR.  173 

We  must   then  apply  to  the  radius  vector  the  corrections  given  by  the 


approximation,  neglecting  terms  of  the  order  of  the  square  of  the  disturbing  forces,  tlie     [40584] 

polar  co-ordinates  will  be    r-\-6r,  v-\-5v,  s-\-&s,   containing  the  twelve  constant  quantities 

a,  h,  c,  &,c.  ;    «',  6',  d,  &ic.,  which  must,  by  the  nature  of  the  question,  be  reduced  to  six 

only,  or  to  six  distinct  functions  Jl,  B,   C,  D,  E,  F,  of  these  twelve  quantities.      The      [4058i] 

values  of  A,  B,   C,  &;c.  may  be  determined  by  the   position,  velocity,  and  direction  of  the 

planet  at  a  given  moment  ;  or  by  the  comparison  of  the  values  of    r-\-ô  r,    v-\-Sv,    s  -\-  ôs, 

with  those  deduced  from  observation  ;  in  each  case  the  result  will  be  fixed  and  determined. 

On  the  contrary,  we  may  assume  at  pleasure  any  values  of  a,  b',  c',  &c.  ;   and  the  values     [4058m] 

thus  assigned  to  these  terms,  will  determine  absolutely  the  quantities  a,   b,  c,  fee,  which 

differ  but  little  from  A,  B,   C,  he.  on  account  of  the  smallness  of  the  disturbing  forces. 


If  we  wish  that  or,  Sv,  &s  should  express  the  effects  produced  by  the  disturbing  forces 
011  the  radius  vector,  the  longitude  and  the  latitude  of  the  disturbed  planet  ;  we  must 
determine    a,    b,   c,    &.c.   so  that  the   elliptical  co-ordinates  r,  v,  s,  and  their  differential 

coefficients     —,    —,    — ,     may  represent  the  position,  the  velocity,  and  the  direction  of 
dt        dt       dt 

the  planet    at   the    commencement  of  this    interval    of   time  ;    and    afterwards   determine 
a,  I',  (,•',  &ic.,  so  that  we  may  have  at  the  same  epoch 


0, 


&v  =  0,         (is=^0; 


d.ir 
~dt 


=  0, 


lit 


=  0, 


d.Ss 
~di 


=  0. 


At  the  end  of  the  time  t,  counted  from  the  same  epoch,  r  will  be  the  distance  of  the  planet 
from  the  sun,  wliich  will  obtain,  if  the  disturbing  force  cease  to  act  from  the  commencement, 
and  0  r  will  be  the  augmentation  of  distance  produced  by  this  force.  Similar  remarks 
may  be  made  relative  to  the  quantities  v,  Sv  ;  or  s,  Ss.  If  we  determine  a',  b',  d  by  other 
conditions,  the  perturbations  of  the  troubled  orbit  will  no  longer  be  loholly  expressed  by  the 
quantities  5  r,  S  v,  S  s  ;  because  the  elliptical  parts  r,  v,  s,  are  also  affected  by  means 
of  the  constant  quantities  a,  b.  c,  Sic,  tvhich  partake  of  the  disturbing  forces,  and  are 
different  from  what  they  would  be  if  these  forces  were  suppressed.  But  this  is  not  attended 
with  any  inconvenience  ;  since  it  does  not  prevent  these  complete  values  of  r  -[-  5  r, 
v-\-Sv,  s  -{-5  s,  from  representing,  at  every  instant,  the  true  position  of  the  planet,  wliich 
is  the  object  of  the  tables  of  its  motion,  into  which  tliese  values  are  finally  reduced. 

Instead  of  considering  directly  the  increments  ô  r,  6  v,  ô  s,  of  the  elliptical  orbit,  we 
may  use  the  method  depending  on  the  variation  of  the  arbitrary  constant  quantities  ; 
supposing  Sa,  Sb,  S  c,  &c.  to  be  the  increments  of  the  constant  quantities  a,  b,  c,  he., 
contained  in  r,  v,  s.  These  six  variable  quantities  S  a,  Sb,  S  c,  &c.  will  be  given  by 
direct  integration  of  formulas  similar  to  [1177],  or  like  those  collected  together  in  the 
appendix  [5786 — 5791],  supposing  that  we  neglect  the  second  and  higher  powers  of  the 
disturbing  forces.      These  values  will  then  be  of  the  forms, 

(5a=^o,  +  a;  Sb  =  b^-\-  fi;  Sc^c,-{-y,     he. 

VOL.  III.  44 


[4058n] 


[4058o] 

[4058p] 

[40589] 

[4058r] 
[4058*] 

[4058*'] 
[4058f| 


174  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

formulas    of    Book   II,    ^50    [1020,   &c.],    and    bj  the    preceding   articles 


[4058u] 


rt, ,  b^,  c,  being  new  arbitrary  constant  quantities,  and  a,  p,  y,  &c.  functions  of  t,  and 
of  a,  h,  c,  &.C.  Substituting  a-\-ôa,  b-{-Sb,  c-\-Sc,  &.C.  for  a,  b,  c,  he.  in  the  values 
of  r,  V,  s,  we  shall  obtain  for  the  co-ordinates  of  the  disturbed  planet,  expressions  which 
are  equivalent  to  the  preceding  values  of  r  -]-  5  r,  v  -\-ôv,  s  -{-  8  s.  The  constant 
[4058t)]  quantities  «^,  f>^,  c^,  &c.,  as  well  as  a,  p,  y,  Sic,  are  of  the  order  of  the  disturbing 
forces;  therefore,  by  neglecting  terms  of  the  second  order,  as  in  [4053s'J,  we  may  put, 
in  the  values  of  a,  p,  y,  &,c.;  a  +  »,  for  a,  ^  +  6,  for  p,  c+c,  for  c,  Sic; 
by  which  means  a-f-a,!  ^-f"^,j  c+c,,  he.  will  be  the  six  arbitrary  constant 
quantities,  which  occur  in  the  values  of  r-\-5r,  v -\- S  v,  s-\-Ss.  This  shows  how  the 
arbitrary  constant  quantities,  contained  in  the  co-ordinates  of  the  disturbed  planet,  as  found 
by  the  two  first  approximations,  are  reduced  to  the  number  corresponding  to  the  system 
of  dilTerential  equations  upon  which  they  depend. 


[4058u»] 


If  ive   ivish    to    chtermint    the    total   effect    of  the    disturbing  forces   upon   each    of 

the  elliptical  elements,   during  a  given  time,  we  must  find,   as  above,  the  constant  quantities 

[4058r]     a,  b,    c,    &c.;    by  means  of  the  position,   the  velocity,  and  the   direction   of   the   planet 

at  the  commencement  of  this  interval  of  time;  and   tlien  the  constant  quantities  a^,  b^,  c, , 

by  means  of  the  equations 

[i058y]  a  -fa  =3  0,  6^-|-p  =  0,  c^-{.y=zO,        kc, 

corresponding  to  the  same  instant.  The  effect  of  the  disturbing  force  at  the  end  of  any 
proposed  time  t,  will  be  expressed  by  means  of  the  quantities  5 a,  Sb,  So,  &c.,  which  will 
then  contain  nothing  arbitrary.  This  is  practised  in  the  theory  of  comets,  In  wiilch  the 
[40582]  values  of  Sa,  5b,  5 c,  he.  are  calculated,  by  quadratures,  for  the  interval  of  time  between 
the  two  successive  appearances  of  a  comet. 

These  general  considerations  agree  with  the  method  used  by  La  Place  in  the  second 
book  of  this  work.  In  the  abovementioned  paper  of  the  Connaissance  des  Terns  for  the 
year  1831,  page  29,  he.,  Mr.  Poisson  has  applied  these  principles  to  the  investigation 
of  the  effect  of  the  whole  disturbing  force  of  a  planet  m',  upon  another  planet  m,  moving 
f4059al  in  the  same  plane.  The  radius  vector  and  the  longitude  of  the  planet  m  being  affected  by 
this  action,  but  not  its  latitude,  because  the  bodies  m,  m'  move  in  the  same  plane.  In  this 
case,  the  six  arbitrary  constant  quantities  mentioned  in  [4058/],  are  reduced  to  four. 
If  we  neglect  terms  of  the  order  e^  in  the  elliptical  motion  of  the  body  rn,  the  expressions 
of  the  radius  vector  and  longitude  [669,  605'],  become 


[40596] 


[4059c]  r=^a  —  ae  .cos.  {n  t -\- s  —  -n)  ; 

[4059d]  t)  =  n  <  +  s  +  2  e  .  sin.  {ni-\-e  —  ra )  ; 

[4059c]  n^a^  =  M^m  =  !x. 

If  we  suppose  the  body  m    to  begin  to  disturb  the  motion  of  m  at  the  commencement 


VI.  v.§20.]         ELLIPTICAL  PART  OF  THE  RADIUS  VECTOR.  175 

[3706 — 4058].      The  expression  of   àr    [1020]  contains  these  two  terms, 

ir  =  —  m'  a  .fe  .  cos.  (7it~\-  s  —  ra)  —  ni'  a  ./'  e'.  cos.  (nt-{-  ;  —  ra')  ;  [4059] 


of  the   time   t,  we  may  determine  the  effect  of  the   perturbation  of  the  radius  vector  by 

means  of  the  value  of  Sr  [1016],  in  whicii  the  arbitrary  constant  quantities  are  retained.     [4059/"] 

The  expression  o{  &v  [I0-21]  would  give  the  perturbations  in  longitude,  if  particular  values 

had  not   been   assigned   to  the  arbitrary  constant  quantities    g,  f,  f.      To  obviate  this 

objection,  we   must  retain   these  arbitrary   quantities   as  they   are   found    in  the  functions 

\\0-2\b,  c,  f/,  e],  whose  sum  is  assumed   in   the  first  line   of  the  note  in  page  556,   Vol.  I     [4059g-J 

[1021e — -/],  for  the  value  of  S  v.      In  order  to  simplify  this  calculation,  it  will  be  convenient 

to  change  the  form  of  the  terms  depending  on  /,  /'  ;    by  developing  the  sines  and  cosines 

of  the  angles     nt-\-s — «,     7it-^s — ra',     into   terms  depending  on      sin.  ?i  ^,    cos.  jj  f, 

by   the    method  used    in    [1023((]  ;    and    changing    the   values    of  the    arbitrary  constant 

quantities  /,  /',    so  that  the  part  of  the  expression  of    —    [1016],  depending  upon  them,     [4059A] 

may  be  put  under  the  form    /.  cos.  n  t  +./  '•  sin.  n  t.      The  corresponding  terms  of  the  value      [40.59t] 
of  5  r  may  be  found  by  multiplying  this  expression  by  2,  and  changing  the  angle  n  t  into 

n  ( -j- 90'' ;    as  is  evident,   by  comparing  the  terms  of    —    [1016],   depending  on   f,  f, 

with  those  of  ay  [1021i];  hence  these  terms  of  àv  become     — 2f  .s\n. nt-\-2f'.  cos.  nt.     [405941 
We  may  also  add  an  arbitrary  constant  quantity  h,  to  the  part  of  <S  v,  computed  in  either 
of  the  integrations  [1021  rf,  f],  and  retain  the  terms 


m'.ant.j3g-\-a.  f  — —  j  ^      [1021t?,  e],  [4059J] 


which  were  put  equal  to  nothing  in  [102iy].      Making  these  changes  in  the  expressions 

or 
of    —,    Sv  [1016,  1021]  ;  neglecting  the  other  terms  of  the  order  c  or  e',  because  this 

degree  of  accuracy  is  sufficient   in  our  present  calculation,  which   is  only  designed  for  the 
purpose  of  illustration  ;  and  supposing  also,  for  brevity,  as  in  [1018a], 


[4059m] 


v  =  n  — n';  T=7i't  —  nt  +  s'  —  s;  G  =  a\  (^^)  ~{- ^  .  a  jî% 

we  get 

—  =  —  2m'.ag—im'. a^.  (  — — ^  +  J m'. n^. 2 .  — . cos. i  T4-f. cos.nt4-  f. sin. n t  ;       [4059n] 

o  \  da  J  f^v-^ — n^ 

&v  =  h  —  'if.%m.nt-\-2f'.cos.nt->rm'.nt.'X3ag  +  a^.(^^\i 

Cna         .,.,  2n3.  G        ?      .      .  _, 

which  are  substantially  the  same  as  the  equations  (5),  (6),  of  Mr.  Poisson,  in  the  paper 


[4059o] 


176 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


f  and  f  being  determined  by  the  two  following  equations,  given  in  [1018], 


[4059p] 
[4059c] 

[4059;] 


abovementioned  ;  observing,  that  i  includes  all  integral  numbers,  positive  and  negative, 
except  i=  0  [1012']  ;  whereas  he  only  uses  the  positive  values  of  i.  Now  if  we  use 
the  expression  of  g  [1017],  the  terms  depending  on    nt    will  vanish  from    &v,    and   then 

&  r  [1020]  will  contain  the  constant  part     |  m  .  a'' 


da 


but    this   is   not   the  whole 


[40595] 


[4059<] 


effect  of  the  disturbing  force  upon  the  radius  vector  ;  because  a  part  of  this  perturbation  is 
introduced  in  the  value  of  7!,  which  is  affected  by  the  value  of  g,  assumed  in  [1017], 
and  n  is  connected  with  a  by  means  of  the  equation   [4059c]. 

We  shall,  for  greater  simphcity,  take,  as  the  epoch,  the  instant  of  the  mean  conjunction 
of  the  planets  m,  m' ;  so  that  we  shall  then  have  <  =  0,  r=0  ;  also  s'  =  s.  We  shall 
also  suppose  that  the  body  m',  at  that  instant,  commences  its  action  upon  the  radius  vector, 
and  upon  the  longitude  of  the  body  m.      Now  we  may  find,  from  the  tables  of  the  planet's 

motion,  the  numerical  values  of    r,   v,    —,     —,     when    t  =  Q;      and  these  are  to  be  put 

equal  to  the  values  deduced  from  [4059c,  f/].  These  four  equations,  being  combined 
with  [4059e],  determine  the  constant  quantities  n,  a,  e,  s,  w  ;  and  then  the  formulas 
[4059c,  t1]  determine  the  elliptical  motion,  which  obtains,  if  the  disturbing  force  cease  to 
act  at  the  epoch  ^  =  0.  This  being  premised,  we  must  put  t^O,  T=^0  [4059r], 
in  the  four  equations   [4058o], 

d.èr        „  d.ôv 

dt 


[4059m] 

[4059t)] 
[4059«i] 


iSr^O;      ,     6v^0;  -^=0;  ^=0; 


and  by  substituting  in  them  the  values  [4059»,  o],  we  may  obtain  the  values  of  the  four 
arbitrary  constant  quantities    g,  f,  f,  h,  introduced  by  the  second  approximation. 

If  we  substitute  these  values  of  g,f,f',  h,  in  5r,  Sv  [4059n,o],  they  will  express,  at  the 
end  of  the  time  t,  the  effect  of  the  disturbing  force  during  that  time.  Now  the  differential 
of  5r  [4059?i],  relative  to  t,  being  found,  and  substituted  in  the  third  equation  [4059<], 
gives  /'=0,  when  t  =  0,  T^O  [4059/-].  With  this  value  of  /',  and  those  of 
5v  [4059o,  «],  together  with    <  =  0,    T=  0,    we  get    A  =  0.      Substituting  these  values 

d.6v 


of   t,  h,  f,  in  the  equations    ^j-  =  0, 
we  obtain  the  follow  ng  equations, 

■d.û<-0) 


dt 


=  0   [4059<],  using  also  the  values  [4059n,  o], 


0  =  —  2  m'.  a  g  —  J  m',  ft^. 


da 


+  i7}i'.n^.S. 


!v9- 


-/; 


0==  — 2/n +  ?«'.«. ^Saj+fl^.r^^^^^—Jm'.  2.^^. «^o- 


2  «3.  G 


[4059:c] 


Multiplying  the  equation   [4059i;]  by   2  n,  and  adding  the   product  to  [4059io]  we  find 
that  the  terms  depending  on    /,     G,    (  —-: J ,     vanish  from  the  sum,  which  becomes 

0  =  —  m.  nag  —  J  m'.  2  .  —  .  a  A^'''  ; 


VI.v.§20.]  ELLIPTICAL  PART  OF  THE  RADIUS  VECTOR.  177 


[4060] 


[m9y] 


whence     s;  =  —  —  .  2  .  .^  '\       Substituting  this  in  [4059y],  we  get 

/=-  — •  2  .  A-'^  +  i  m'.  «2.  (  — —    —  I  m'.  n^  2  .  :^^ — -  . 

By  means  of  the  values  of  /',  /(,  g,  f  [4059it,  y],  the  expressions  [4059m,  o]  become 

—  = .2.^^''.(1  — COS.ÎtO irn.rt^.     .(1 COS.?in 

a  V  \  d  a  / 

f.  _  [40592] 

+  i  m.  11^.  2 .— —; ;  •  (cos.  i  T — cos.  n  0  ; 

C       San  .,.,    ,      „    /d.mx} 


2\ 


[4059z'] 


[40600] 


[40606] 


If  we  retain  merely  the  non-periodical  parts  of  r,  v,  5r,  Sv  [4059f,  d,  z,  s'],  and 
resubstitute  the  value  of  v  [4059m],  we  shall  get 

,    ^  ,    m'.a^n  ....       .      ,     „  fd.m\ 

'  '     »i— n  \da  / 

v4-5v  =  nt-\-i-^m'.nt.]^- .  2.  ^'^-fa^.  (— —  )C  ; 

'  '        '  t      2.()i— 7i')  \  da  /  !)  ' 

for  the  expressions  of  the  mean  distance  and  mean  longitude  of  the  planet  m- 

The  expressions  of  the  same  mean  distance  and  mean  longitude,  according  to  La  Place's 
calculation  [1020,  1021],  are 

r-\-àr  =  a-\-\m:.a^.(^-^\,  v  +  àv  =  nt.  [4060c] 

The  differences  between  these  values,  and  those  in  [4060a,  &],  are  merely  apparent,  and 
arise  from  using  different  values  of  n,  a,  in  [4060c]  from  those  in  [4060a,  i].  To 
render  this  evident,  we  shall  suppose,  for  a  moment,  that  n,  t  represents  the  mean  motion 
of  the  planet  m,  derived  from  observation  ;  then,  by  putting  the  coefficient  of  t,  in  the 
equation  [40606],  equal  to   n^t,    we  shall  have 

,       /         <^  3an        ^     am     i      2   fdA^^  ^  [4060d] 

^  i        2.(n— 7i')  '  \    da    J  <) 

VOL.  III.  45 


178  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

The  preceding  part  of  the  radius  vector  [4059]  may  be  united  in  the  same 
table  with  the  elliptical  part  of  the  radius.* 


Let   a,   be  the  value  of  a,  deduced  from  the  equation      a  =  fA^.?i     '•'     [4059f],    when 
'•        *■'     n,  is  substituted  for  ?t  ;    so  that  this  equation    holds  good  for   a,  n,  and  also  for  «^ ,  n,  ; 
we  shall  have  successively,  by  development,  neglecting  the  square  of  n, —  n, 

Substituting  in  this  the  value  of    n^  —  n  [4060cZ],   we  get,  by  transposition, 

[4000^]  «=-«'+«»•«•  1-2-:i;;=;ô-'--^+"-V-^)  I  • 

This  value  of  a  being  substituted   in  [4060«],  we  find,   that  the   parts  depending  on  A'-''' 

destroy  each  other,  and  we  have 

/  d  A'-O'i  \ 
[4060/i]  '•  +  (5  ?•  =  a,  +  ^  ?«'.  a^.  \~J^)  • 

Now  as  we  neglect  terms  of  the  oi'der  m  ^,  we  may  change  a  into  «, ,  in  the  part  depending 
on  ^""  ;  and  then  the  expression  [4060/t]  becomes  of  the  same  form  as  in  [4060f]  ;  being 
equivalent  to  that  found  by  La  Place.  This  calculation  serves  to  illustrate  and  confirm  his 
[40(j0i]  method  of  calculation  ;  and  shows,  at  the  same  time,  how  we  can  dispose  of  the  additional 
arbitrary  constant  quantities,  which  are  introduced  by  the  integrations  of  6  ?•,  Sv;  so  as  to 
conform  to  the  actual  situations  and  motions  of  the  attracting  bodies  ;  and  to  investigate  the 
part  of  the  effect  of  the  disturbing  forces,  that  we  have  particularl}'  considered  in  this  note. 

*  (2552)    We  have  here  omitted  a  clause,  in  which  the  author  directs,  that  the  sign 
[4060ft]    of  the  term  of  f,  depending  on    cldA^^'',   should  be  changed;  because  we  have  previously 
corrected  the  mistake,  and  given  the  accurate  expression  of  /'  in  [1021g-],  which  agrees 
with  that  in  [4060]. 


VI.  vi.<^21.] 


NUMERICAL  ELEMENTS. 


179 


CHAPTER    VI. 

NUMERICAL   VALUES  OF  THE  DIFFERENT  QUANTITIES   WHICH  ENTER  INTO  THE  EXPRESSIONS   OF  Till; 

PLANETARY  INEaUALITIES. 

21.    To  reduce  to  numbers,  the  formulas  contained  in  the  second  book 
and  in  the  preceding  chapters,  we  shall  use  the  following  data  ; 

Masses  of  the  Sun  and  Planets* 
Sun, M  =  1  ; 

Mercury, m  =  ^^  ;  log.  m  =  93,6934013  ; 

Venus, m'  =:  j^  ;  log.  m'  =  94,4166538  ; 

The  Earth, m"  =  j^^  ;  log.  m"  =  94,4819733  ; 

Mars, m"'==  \^~  \  log.  w"'=  93,7337490  ; 

Jupiter, ^"=1^^  ;        log-  m"  =  96,9717990  ; 

1067,09  ° 

Saturn, vf  =  ^±^  ;        log.  m"  =  96,4737383  ; 

Uranus, m"=  "^^  ;        log-  m"=  95,7098763. 

*  (2553)    The  factors    l+fx,    1+(ji',    Uc.  in  the  values  of  m,  m',  &c.  [4061],  are 
not  inserted  in  the  original  work  ;  but  as  they  are  introduced  in  [4230'],  and  frequently 


Masses 
of  the 
planets, 
the  masi 
of  the 
sun  beiiii? 
unity. 


[4061 J 


[4061o| 


180 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


Of  all  these  masses,   that  of  Jupiter  is  the  most  accurately  determined  ; 
it  is  obtained  by  means  of  the  formula  [709].       If  we  put   T   for  the  time 


[40615] 


[4061c] 


Masses 
finally 
adopieil 
by  the 
author. 


[406  W] 


used  in  computing  the  perturbations  of  the  motions  of  the  planets,  it  was  thought  best, 
for  the  sake  of  convenient  reference,  to  insert  them  in  this  place.  When  the  author  printed 
this  part  of  the  work,  he  supposed,  in  conformity  with  the  best  observations,  which  could 
then  be  procured,  that  the  masses  of  the  planets  were  as  in  the  table  [4061],  putting  each 
of  the  quantities  (x,  (a',  &ic.  equal  to  zero.  Since  tliat  time,  he  has  been  induced,  by  other 
observations,  to  make  successive  corrections  in  these  masses,  as  in  [4605,  4608,  9161,  &c.]. 
In  his  last  edition  of  the  Système  du  Monde,  he  adopts  the  following 


Corrected  Masses  of  the  Planets. 

^  (A  =0;  log.  ??i   =93,6934013; 

^'  =z  —  0,0.56030  ;  log.  m    =  94,3916120  ; 

(a"  =  —  0,0T1297  ;  log.  m"  =  94,4498499  ; 

(;/"=  —  0,275000  ;  log.  m'"  =  93,5940870  ; 

|xi-=  —  0,003186  ;  log.  m'':=  96,9704133  ; 

f;.^  =  —  0,043451  ;  log.  m'  ==  96,4544455  ; 

ij:'=      0,088514  ;  log.  m"''  =  95,7467105. 


Saturn, nf  = 

Uranus, m''  = 


The  alterations  here  made  in  tlie  values  of  »«',  ?»"',  are  in  conformity  with  the  results  of  the 
calculations  of  Burckhardt,  in  his  late  solar  tables,  by  comparing  the  observed  perturbations 

[4061e]  of  the  earth's  orbit  with  the  theory.  The  change  in  the  value  of  m",  arises  from  the 
supposition,  that  the  sun's  horizontal  parallax  is  nearly  equal  to  8',6  [5589],  instead  of  8^,8, 
assumed  in  [4073].  Lastly,  the  values  of  nt",  m'',  m'",  are  obtained,  by  Mr.  Bouvard, 
from  the  observations  used  in  constructing  his  new  tables  of  Jupiter,  Saturn,  and  Uranus,  by 
comparing  the  theory  with  the  actual  perturbations  depending  upon  their  mutual  attractions. 

[4061/]  Putting  the  values  in  [4061]  equal  to  those  in  [4061fZ],  respectively,  we  get  the 
corresponding  values  of  (a,  f.'/,  he.  [4061f/].      Lindeneau,  in  his  tables  of  Mercury,  printed 

r4061ffl  ill  1813,  supposes  that  the  mass  of  Venus  ought  to  be  increased  to  a-jaVioJ  making 
|j,'=  0,09643  nearly;  to  satisfy  the  perturbations  of  Mercury,  by  the  action  of  Venus. 
Encke,  in  his  Astronomisches  Jahrbuch  for  1831,  states,  that  the  mass  of  Jupiter  tû5  j.fls^  > 
deduced  by  Nicolai,  from  the  perturbations  of  Juno,  agrees  better  with  the  observations 

[40G1/I.]     of  Pallas  and  Vesta,  than  the  mass  adopted  by  La  Place  [4061,  4065],  and  that  it  probably 


VI.  vi.^21.]  NUMERICAL  ELEMENTS.  181 

of  the  sidéral  revolution  of  the  planet  m'  ;    T  for  that  of  one  of  its  satellites  ; 

q  for  the  sine  of  the  greatest  angle,  under  which  the  mean  radius  of  the 

orbit  of  this  satellite  appears,  when  viewed  from   the   centre  of  the  sun,      [40G2] 

at  the  mean  distance  of  the  planet  from  that  centre  ;   then  the  mass  of  the 

sun  being  taken  for  unity,  that  of  the  planet  will  be  expressed  by  * 


T 


.,r! 


\-q\ 


7=— i;  =  mass  of  the  planet.  [4063] 


T 


[4061&] 


agrees  also  better  for  Vesta.  Comparing  this  with  [4061],  we  get  (a''' =0,012492.  When  [406lt] 
we  take  into  consideration  that  \he  first  value  of  fi''==0  [4061,  4065]  is  obtained  from  the 
observed  elongations  of  the  sateUites  of  Jupiter;  the  secondvdXue,  (a'=  —  0,003186  [4061«/], 
from  the  perturbations  of  Saturn  and  Uranus  ;  the  third  value,  (^'=0,012492  [4061z], 
from  the  perturbations  of  the  newly  discovered  planets  ;  we  shall  not  be  surprised  in  finding 
these  small  diflerences  in  the  results  of  methods,  which  are  so  wholly  independent  of  each 
other.  Nothing  is  known  relatively  to  the  masses  of  these  new  planets  or  the  masses  of  the  [4061ot] 
comets,  except  that  they  are  all  very  small  ;  so  that  their  action  on  the  other  bodies  of 
the  system  is  wholly  insensible. 

*  (2554)    This  is  deduced  from  [709],      —^^  —  .i—\,     in  which  we  must  write     [4062a] 

I*  for  M,  as  is  evident  from  [706']  ;  and  as  m'  represents  the  mass  of  the  planet,  in  the 
present  notation,  we  have  n  =  M  +  ?»'.  Moreover  p  is  the  mass  of  the  satellite  [Î07'], 
and  M  that  of  the   sun  [706']  ;    h   the  mean  distance  of  the   satellite   from   the  planet  ; 

a  the  mean  distance   of  the   planet   from   the  sun  ;    so  that     —     represents  the  quantity 


we 


[40626] 
[4062c] 


q  [4062]  ;  hence  the  preceding  equation  [4062a]  becomes     -  J^   ,  =  ^^   /      \         if 

/  T  \  2        1 
neglect  p  in  comparison  with  m',  and  put    JW=  1  ;    also,  for  brevity,     cf.  (—\  =~  ,     we 

a         1 

get,  as  in  [4063],     m'=^ =- — -  .       If  we  put  r,  p"  for  the  mean  densities  of  the     [4062rf] 

1_-       ft-i 

bodies    m'',    m";    also    R'%    R"  for  the  radii  ;   we  shall  have  nearly,  as  in  [2106], 

?«>'■=  4  *  .  piv.  (/3iv^3 .  ^v  ^  I  ^  ^  pv_  ^ji-y^  [4062e] 

Hence  we  easily  obtain    the  relative  densities  of  these   two  bodies,       ^~  =  —  .(-—]  •     [4062/1 

pv        m^     yR'"  / 

This  may  be  used  for  ascertaining  the  densities  of  all  the  bodies,  whose  masses  are  known, 

and  whose  apparent  diameters  have  been  well  observed. 

VOL.  III.  46 


182  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

We  have,  relatively  to  the  fourth  satellite,* 

q  =  sin.  1530",38  =  sin.  495',84  ; 
[4064]  T  =  4332'")%602208  =  433244*  27"- 10',8  ; 

r=  16'^'",6890  =  16"16''32"'09-,6. 

From  [4063,  4064],  we  obtain 
[4065]  m" 


[4064a] 


1067,09 

The  mass  of  Saturn  is  found  by  the  same  method  ;  supposing  the  sidéral 
revolution  of  its  sixth  satellite  to  be  15"'''%9453  =  15"22"41'"  13',9,  and 
the  greatest  angle,  under  which  the  mean  radius  of  the  orbit  of  this  satellite 
appears,    when   viewed    from    the    sun,    in   the    mean   distances   of   Saturn, 

[4066]  552'',47=179'.  The  mass  of  Uranus  has,  in  like  manner,  been  obtained,  by 
supposing,  conformably  to  the  observations  of  Herschel,  that  the  duration  of 
the  sidéral  revolution  of  its  fourth  satellite,  is    13'''ys4559  =  13'10''56'"29',8; 

[4067]  jji^j  ^]^Q  mean  radius  of  the  orbit  of  tliis  satellite,  viewed  from  the  sun, 
at  the  mean  distance  of  Uranus,  13S",512  =  44',23.  But  the  greatest 
elongations  of  the  satellites  of  Saturn  and  Uranus  have  not  been  so 
accurately  ascertained  as  that  of  the  fourth  satellite  of  Jupiter.  Observations 
of  these  elongations  deserve  the  careful  attention  of  astronomers. 

The  mass  of  the  earth  is  found  in  the   following  manner.      If  we  take 

the  mean  distance  of  the   earth  from  the   sun  for  unity,  the  arc  described 

by  the  earth,  in  a  centesimal  second   of  time,  will  be  obtained  by  dividing 

the  circumference   of  a    circle,  whose   radius  is  unity,    by   the   number  of 

[4068]      seconds  in  a  sidéral  year,    36525638"''-,4.      Dividing  the  square  of  this  arc 

[4068]     by  the  diameter,  we  obtain  its  versed  sine  =  — r;^»^  jf    which  is  the  space 

the  earth  falls  towards  t!ie  sun  in  a  centesimal  second,  by  means  of  its 
relative  motion  about  the  sun.      On  the  parallel  of  latitude,  whose  sine  is 


*  (2555)    The  values  of   c/,   T  [4064],  are  nearly  the  same  as  those  used  in  the  theory 
of  this  satellite  [6781,6785]  ;  the  value  of  T  corresponds  to  the  mean  motion  n'"  [4077]. 


t  (2556)    The  radius  of  the  orbit  being  1,  its  circumference  is  6,28.318  nearly;    if  we 
[4068a]     divide  this  by  36525638,4,  and  take  half  the  square  of  the  product,  we  get  the  expression 
of  the  versed  sine,  corresponding  to  this  arc,  as  in  [4068']. 


VI.  vi.  }21.] 


NUMERICAL  ELEMENTS. 


183 


equal  to  \/},  the  attraction  of  the  earth  causes  a  body  to  fall  through 
3""", 66553*  ill  one  centesimal  second.  To  deduce  from  tiiis  the  earth's 
attraction  at  the  mean  distance  of  the  earth  from  the  sun,  we  must  multiply 
it  by  the  square  of  the  sine  of  the  sun's  parallax,  and  divide  the  product  by 
the  number  of  metres  contained  in  that  distance.  Now  the  earth's  radius 
on  tlie  proposed  parallel,  isf  6369374'™'-;  therefore,  by  dividing  this 
number  by  the  sine  of  the  sun's  parallax,  supposing  it  to  be  2T',2  —  S%8, 
we  obtain  the  mean  radius  of  the  earth's  orbit,  expressed  in  metres.  Hence 
it  follows,  that  the  effect  of  the  attraction  of  the  earth,  at  a  distance  equal 
to  that  of  the   mean  distance  of  the    earth   from   the   sun,    is  equal   to   the 

product  of  ihe  fraction  i'^'^^.,  by  the  cube  of  the  sine  of  27",2  ; 
^  bSby-i  1 4 

consequently    it    is   equal    to  J 


10- 


Subtractins    this  fraction   from 


1479565 
10-33-' 


we  obtain      — 


1479560,5 


10- 


for  the  effect  of  the  attraction  of  the  sun, 


[4069] 


[4069'] 
[4070] 


[4071] 
[4071'] 


*  (2557)  This  computation  varies  a  little  from  that  in  [388"]  or  in  [3SSf/]  ;  probably 
owing  to  a  small  difference  in  the  ellipticity,  used  in  reducing  the  observations. 

t  (25.58)  LT^sing  the  polar  and  equatorial  semi-axes  of  the  earth,  6356677™'-, 
6375709"'"''  [2035i],  whose  difference  is  19032""^'-,  we  find  the  radius  corresponding  to 
the  latitude,  whose  sine  is  /-L,  to  be  6375709""='-  —  i  X  l9032'"'='-=  6369365""^'-, 
agreeing  nearly  with  [4069']. 

J  (2559)  Gravity  decreases,  in  proceeding  from  the  earth's  surface,  inversely,  as  the 
square  of  the  distance  of  the  attracted  point  ;  or  as  the  square  of  the  sine  of  the  horizontal 
parallax  of  that  point  nearly.  Hence  the  earth's  attraction,  at  the  distance  of  the  sun, 
will  cause  a  body  to  fall  through  a  space  represented  by  3"""-,66553  X  (sin.  O's  par.)"^, 
in  one  centesimal  second  of  time.  To  reduce  this  from  metres  to  parts  of  the  mean 
distance  of  the  earth  from  the  sun,  we  must  divide  it  by  that  distance,  which  is  evidently  equal 

earth's  radius        6-369374 '"o'-  r  n  i  i    • 

so  that  the   space   lallen   through  m  a  second,  becomes 


to 


sin.27",2 

\3. 


sin.  Os' par. 

^ô^\~  ■  ■  (sin-  Q's  par.)^  = ,     as  in  [4071'!.      Now  in  [4063'],  we  have  found,  that 

Doo9.!}/4  10-0  ■-  -"  ■-  -• 

the  earth  falls  towards  the  sun,  in  the  same  time,  by  the  combined  action  of  the  sua  and 

1479565  —  4,488.5        1479560,5 


earth 


1479565 
10^0     ' 


nearly  ;  and  as  that  of  the  earth  is 


hence    the   effect    of    the    sun    alone    is 

4,4885 


low  ' 

4,4885  1479560,5  „^„„,  ,  ■        .      r.-, 

to    — ,^.,„      ,     or  1   to  329630  nearly,  as  in   [4072]. 


1020  1020 

the  mass  of  the  earth  is   to  that  of  tiie  sun 


[4069a] 


[4070a] 


[4071a] 
[40716] 


[4071c] 


[4071rf] 


lOio 


10-0 


184  PERTURBATIONS  OF  THE  PLACETS;  [Méc.  Cél. 

at  the  same  distance.       Hence  the  masses  of  the  sun  and  earth  are  in  the 
ratio  of   the    numbers    1479560,5    to   4,4885;    consequentlj  the   mass    of 

[4072]      the  earth  is  .       If  the  sun's  parallax  differ  a  little  from  the  quantity 

we  have  assumed  in    [4070],  the  value  of  the   earth's  mass  will  varv  as 
[4073]      the  cube  of  that  parallax,  compared  with  the  cube  of   21", 2  =  8",8  [4071c]. 

We  have  computed  the  mass  of  Venus  from  the  formulas  [4251, 4332,  &c.], 
which  express  the  secular  diminution  of  the  obliquity  of  the  ecliptic  to  the 

[4074]  equator;  supposing  it,  by  observation,  to  be  154',30^50'.  This  diminution 
is  obtained  from  those  observations  which  appear  the  most  to  be  relied  upon.* 
With  respect  to  the  masses  of  Mercury  and  Mars,  we  have  supposed,  according 
to  observation,  that  the  mean  diameters  of  Mercury,  Mars,  and  Jupiter, 
viewed  at  the  mean  distance  of  the  earth  from  the  sun,  are,  respectively, 

[4075]  21",60  =  7-;  35",19  =  11%4;  626",04  =  202-,84.  Now  Jupiter's  mass 
being  ascertained,  we  could,  by  means  of  these  diameters,  obtain  the  masses 
of  Mercury  and  Mars,  if  the  relative  densities  of  these  three  planets  were 
known.  It  we  compare  the  masses  of  the  Earth,  Jupiter,  and  Saturn, 
with  their  magnitudes,  respectively,  we  find,  that  the  densities  of  these 
planets  are  very  nearly  in  the  inverse  ratio  of  their  mean  distances  from  the 


*  (2560)    K  we  change    7,  A    [310-2f]   into   0",  «",    respectively,    to   confonn  to  the 

[4074a]     notation  used  in  [4082.  4083]  ;   we  shall  find,  that   the   arc     F  G^y .  cos.  A   [3109c], 

which  represents  the  difference  between  the  inclinations  of  the  equator  to  the  fixed  echptic 

of  1750  and  to  the  variable  ecliptic  of   1750  -|-  ^j    is  equal  to     o".  cos.  é",  or  q"  [4249]. 

[40746]     The  value  of  q"  is  found  by  integrating  the  second  equation  [4251].      In  this  expression 

of   q",   the  coefficients  of    fi,  fif",  (1%  fi",    are  small,  and  the  value  of  i^'^  [4061  J]  is  small 

and  tolerably  well  ascertained  ;    therefore  we  need   only  retain    /.    so  that   the    intesn^ 

[4074c]     becomes      q"  =  —  ( 0". 500955  -p  0',309951 .  ,u.')  .t.       If  we  suppose    ,a'  =^  0,    the  annual 

[4074dl    decrement  becomes  0*..500955,  being  nearly  as  in  [4074].     The  action  of  the  planet  Venus 

has  more  effect  in  producing  this  change  of  obliquity,  than  that  of  all  the  other  planets 

taken  together;    as  is  evident  fcom  the  inspection  of  the  value  of  d q''  [4251];  in  which 

[4074e]     we  find,  that  the  coefficient  of  ,a'  exceeds  the  sum  of  the  coefficients  of  the  other  quantities, 

ji,  (i'",  11'",  (Ji\  fi".      We  have  already  remarked,  in  [3380/! — q],  that  the  author  increased 

the  annual  variation  to  0'\521154  [4613]  ;   on  the  other  hand,  Mr.  Poisson  uses  0  45692 

[4074/1    [33Sqp],  and  Mr.  Bessel  0-',48368  [3380j]  ;  each  of  them  varying  the  values  of  ,a,  ^',  &c., 

so  as  to  conform  to  their  assumed  decrements. 


VI.  vi.§21]  NUMERICAL  ELEMENTS.  186 


1  /  O  \3    a"  ,„  1  /D"'\3  a'" 


'  "'    ine-r  nn  '  \  7)iv  ^   •  „w  J 


1067,09     V-D'V      «  1067,09    V^ 

and  by  substituting  the  values  [4076c,  4079],  we  get,  for  m,  m",  rather  greater  values 
than  those  in  [4061].  These  diflerences  probably  arise  from  having  used  different  values 
of   D,  D",  D\  which  cannot  be  obtained,  by  observation,  to  a  great  degree  of  accuracy. 

In  some  of  the  subsequent  calculations,  it  will  be  sufficiently  accurate  to  use  the  values 
of  n,  n,  Sic.  to  the  nearest  degree;  and  for  convenience  of  reference  we  have  here 
inserted  these  approximate  values  ; 

71=1661°;      7i'=650°,       n"=400^,       n"'=212=',7,       w»  =  330,7, 

n-  =  13^,6,      ■nr'  =  4P,Q. 
VOL.  III.  47 


[4076] 


sun  ;*  we  shall  therefore  adopt  the  same  hypothesis,  relatively  to  the  three 
planets  IMercury,  Mars,  and  Jupiter  ;  whence  we  obtain  the  preceding 
values  of  the  masses  of  IVIercury  and  Mars  [4061].  The  irradiation 
and  the  other  difficulties  attending  the  measures  of  the  diameters  of  the 
planets,  taken  in  connexion  with  the  uncertainty  of  the  hypothesis  adopted 
on  the  law  of  their  densities,  render  these  estimated  values  somewhat 
doubtful,  and  this  uncertainty  seems  to  be  increased  from  the  circumstance, 
that  the  hypothesis  is  not  correct  relative  to  the  masses  of  Venus  and 
Uranus.  Fortunately,  Mercury  and  Mars  have  only  a  very  small  [4076] 
influence  on  the  planetary  system  ;  and  it  will  be  easy  to  correct  the 
following  results,  so  far  as  they  are  affected  by  this  cause,  whenever 
the  development  of  the  secular  inequalities  shall  make  known  exactly  the 
values  of  these  masses. 


*  (2561)  The  densities  of  the  Earth,  Jupiter,  and  Saturn,  given  by  the  author  in  the 
Système  du  Monde,  are  3,93  ;  0,99  ;  0,55  ;  respectively,  being  found  as  in  [4062/,  Sic.].  [4076a] 
These  densities  of  Jupiter  and  Saturn  are  nearly  in  the  inverse  ratio  of  the  distances 
a",  a"  [4079]  ;  but  the  density  of  the  earth  differs  considerably  from  this  rule.  If  we 
suppose  this  ratio  of  the  densities  to  hold  good  for  the  three  planets  Mercury,  Mars,  Jupiter,  and 
represent  their  apparent  diameters  [4075],  by    D=21",60,    I>"'=35",19,   -D'^=:626",04;     [4076c] 


[40766] 


#13  n"'3  71' ^3 

the  corresponding  masses  will  be      m  =  b  .  — ;      ?»'"=  b  .  —^  ;      m''=  J  .  — —  ;      i  being     [4076(f] 
a  constant  quantity,    to   be   found    by  means   of  the   value    of   m'"  [4061]  ;    which  gives 


[4076/] 


[4076^] 


[4076A] 


186 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Mean 
motions 
of  the 

planets. 


[4077] 


[4078] 


The 

time  t  18 
expressed 
in  Julian 
years. 


Mean 
distances 
of  the 
planets 
from  the 
flun. 


[4079] 


22.    Mean  sidéral  motions  of  the  Planets  in  a  Julian  year  of  365|  days, 

or  the  values  of  n,  n',  &c. 


Sexagesimals. 


Mercury,  .n  =  16608076",50  =  5381016%786  ;  log.  n  =6,7308643 

Venus, .  .  .  n'  =  6501980",00  =  210664r,520  ;  log.  n'  =6,3235906 

The  Earth,  n"  =  3999930",09  =  1295977%349  ;  log.  n"  =  6,1 125974 

Mars, n"'=  2126701",00=   689051%124  ;  log. /i"'  =  5,8382514 

71'"=  337210",78=    109256-,293;  log.  ?i'^  =  5,0384465 

n^  =  135792",34=     43996%718;  log.  n^  =  4,6434203 

n''=  47606",62=      15424^545,  log.  n"  =  4, 1882124 


Jupiter, 
Saturn, 
Uranus, 


If  we  use  these  values  of  n,  n',  &c.,  the  time  t  ivill  be  represented  in 
Julian  years  ;  hence  if  we  put  the  mean  distance  of  the  earth  from  the  sun 
equal  to  xmity,  we  shall  obtain,  from  Kepler's  law  [385'"],  the  following 
mean  distances  of  the  planets  from  the  sun. 

Mean   distances   of   the    Planets  from   the    Sun,    or   the   semi-major    axes 

of  their  orbits.* 


Mercury, a   =    0,38709812 

Venus, «'  =    0,72333230 

The  Earth,    a"  =    1,00000000 

Mars, «'"=    1,52369352 

Jupiter, a'^  =    5,20116636 

Saturn, a"  =    9,53787090 


Uranus, a" 


19,18330500 


log.  a 


log.  a' 


9,5878211 
9,8593379 
log.  a"  =  0,0000000 
log.  «'"=0,1828976 
log.  rr  =  0,7161007 
log.  a"  =  0,9794514 
log.  «^'  =  1,2829234. 


*  (2562)    These  values  of    «,  a',  &C.   are   deduced  from    [4077],    by   putting  them, 
[4079a]     respectively,  equal  to      I — V,      (  —  r,       (— :F,       &c. 


The  elements  of  the  orbits  of  the  newly  discovered  planets,  Ceres,  Pallas,  Vesta,  and 
Juno,  were  first  computed  by  Gauss,   and   have  since  been  repeatedly  corrected  by  him, 


VI.vi.§â-2.] 


NUMERICAL  ELEMENTS. 


187 


The  mutual  action  of  the  planets  alters  a  little   their  mean  distances  ;  we 
shall,  in  [4451,  4510],  determine  these  alterations. 


aiul  by  other  astronomers  ;    taking   notice  of  the  most   important  perturbations,    from   the      [40794] 

action   of  the  nearest  phinets  ;  so   that  we  can  now  compute   the   places   of  these  bodies 

with  a  considerable  degree  of  accuracy.      The   usual  methods   of  finding  the  perturbations 

can  be  applied  to  these  small  planets  ;    but  the  great  excentricities  and  inclinations  of  some     [4079eJ 

of  their  orbits,   will  make  it  necessary,  when  great  accuracy  is  required,  to  notice  the  terms 

depending  on  the   powers  and  products  of  these  two  elements,   of  a  higher  order  than  is 

generally  used  with  the  other  planets.     The  laborious  task  of  ascertaining  all  the  inequalities 

of  these  four  planets,  was  not  performed  by  the  author  of  this  work  ;  and  it  will  probably  be    [4079<i] 

a  long  while  before  it  can  be  done  completely,  on  account  of  the  small  imperfections  in  the 

present  estimated  values  of  the  elements,  which  have  not  yet  been  determined  with  perfect 

accuracy  in  the  short  period  since  the  bodies  have  been  observed.       It  is  evident,  also,  that     [4079e] 

until  these  elements  have  been  found  very  nearly,    it  will  not  be  of  much  use  to  compute 

several  of  the  very  small  inequalities,  with  tiie  extreme  minuteness  which  is  used  relatively 

to  the  other  planets. 

In  computing  the  Jahrluch,  it  has  been  found  most  convenient  by  Encke  to  apply  the 
corrections  directly   to   the  elements  of  the   orbit,    rather   than   to  the   elliptical  places  of    [4070/'] 
the  bodies  ;   in  a  manner  similar  to  that  which  is  used  in  finding  the  elements  of  a  comet,  in 
two  successive  returns.      He  finds,  when  the  elements  are  thus  adjusted  to  any  particular    [407yg'] 
moment  of  time,  that  they  will  give,  tolerably  well,  the  places  of  the  planet  for  a  considerable 
period,  on  each  side  of  this  epoch.      The  elements  of  the  orbits  obtained  by  him,  for  these 
four  planets,   about  the  time  of  the  opposition  of  Pallas,  in   the  year  1831,  are  as  in  the    [4079A] 
following  table  ;  which  will  serve  to  give   an  idea  of  the  relative   positions  of  the   orbits 
at  that  time  ;  remarking,  that  these  elements  must  not  be  confounded  with  the  memi  values. 


Epoch  1831,  July  23d,  0'',  mean  time  at  Berlin. 


I  Vesta. 

Mean  longitude, 84'' 47"  03' 

Mean  anomaly, 195  35   26 

Longitude  of  the  perihelion,  ....  249  11    37 

Longitude  of  the  ascending  node,  .  103  20   28 

Inclination, 7  07    57 

Excentricity, 0,0885601 

Mean  daily  sidéral  motion, 97775540 

Semi-major  axis, 2,.361484 

Periodic  revolution  corresponding,  .  1325,5  days 


74''39"'44' 
20  22  31 
54  17  13 

170  52  34 
13  02  10 
0,2555592 

813',525.33 
2,669464 

1593,1  days 


290'' . 38"' 12»- 

169  33  11 

121  05  01 

172  38  30 

34  35  49 

0,2419986 

768%54421 

2,772631 

1686,3  days 


Cereg. 

307'' 03'"  26'- 

159  22  02 

147  41  23 

SO  53  50 

10  .36  56 

0,0767379 

769-26059 

2,770907 

1684,7  days 


Elements 
of  Veatu, 
Juno, 
Pallas, 
and  Ceres. 


[4079i] 


188 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


Eicen- 
tricities  of 
the  orbits 
of  the 
planets. 


[4080] 


Ratios  of  the  excentricities  to  the  mean  distances,  or  the  values  of   e,  e',  ^c. 

for  the  year  1750. 


Mercury, e    =  0,20551320 

Venus, e'  =  0,00688405 

The  Earth, e"  =0,01681395 

Mars, e"=  0,09308767 

Jupiter, e''  =  0,04807670 

Saturn, e''  =  0,05622460 

Uranus, e"  =  0,04669950 


log.  e  =9,3128397; 
log.  e'  =  7,8378440  ; 
log.  e"  =  8,2256698  ; 
log.  e"'=  8,9688922; 
log.  e"=  8,6819346; 
log.  &■  =  8,7499264  ; 
log.  e''=  8,6693122. 


[407M] 


[4079Z] 


Elements 
of  the 
orbits  of 
the  four 
known 
periodical 
comets. 


[4079m] 


[4079n] 


The  distances  of  tlie  planets  Pallas  and  Ceres  from  the  sun,  are  so  nearly  equal  to  each 
other,  that  it  may  sometimes  happen,  in  finding  the  apparent  orbits,  in  the  precedins; 
manner,  that  the  order  of  the  bodies  will  be  inverted,  relative  their  distances  from  the  sun, 
by  means  of  the  perturbations. 

Besides  these  planets,  there  are  four  comets,  whose  periodical  revolutions  have  been 
discovered  by  Halley,  Gibers,  Encke,  and  Biela.  They  have  been  usually  called  by  the 
names  of  the  discoverers  i-espectively.  That  of  Olbers  has  been  observed  only  once,  at 
the  time  of  its  return  to  the  perihelion  in  1815  ;  the  others  have  been  observed  in  several 
successive  revolutions. 

Periodic  revolution, 

Time  of  perihelion, 

Longitude  of  perihelion  on  the  orbit, 
Longitude  of  the  ascending  node, 

Inclination, 

Excentricity, 

Semi-major  axis, 

Of  the  seven  periodical  bodies,  which  have  been  made  known  to  astronomers  since  the 
commencement  of  the  present  century,  three  were  discovered  by  Dr.  Olbers  of  Bremen  ; 
namely,  Vesta,  Pallas,  and  the  comet  of  1S15.  His  great  success  in  the  discovery  of 
these  remarkable  bodies,  which  had  silently  performed  their  revolutions  in  the  heavens 
for  ages,  unperceived  by  astronomers,  induced  an  eminent  German  writer  to  style  him» 
the  fortunate  Columbus  of  the  planetary  ivorld. 


Halley's. 

Olbeis's. 

Encke's. 

Biela's. 

7G  years 

74  years 

1204  days 

6,7  years 

Nov.  7, 1835 

April  26,1815 

Jan. 10, 1829 

Nov.  27,1832 

304' 31  "'43' 

149"^   2-" 

157'^18'"35' 

109'' 56™  45' 

55  ,30 

83  29 

.334  24    15 

248  12  24 

17  44   24 

44  30 

13  22   34 

13  13   13 

0,9675212 

0,9313 

0,8446862 

0,751748 

17,98705 

17,7 

2,224346 

3,-53683 

VI.vi.§22.] 


NUMERICAL  ELEMENTS. 


189 


Longitudes  of  the  perihelia  in  the  year  1 750,  or  the  values  of  ^,  ts',  ^c. 

Mercury, «   =    8P,7401  =    13'33^5S' 

Venus, • ^'  =  142°,1241  =  127  54  42 

The  Earth, ^"  -=  109^,5790  =    98  37    16 

Mars, ^"'  =  368°,3037  =  331  28   24 

Jupiter, ^'"^    11°,5012=    10  21   04 

Saturn, zy"  =    97°,9466  =    88  09   07 

Uranus, ^"=  185°,1262  =  166  36  49. 

Inclinations  of  the  orbits  to  the  ecliptic  in   the  year  1750,  or  the  values 

of  f,  <p',   ^c. 


Loagitudes 
of  the 
perihelia 
in  1750. 


[4081] 


Mercury, 

Venus, 

The  Earth, cp"  = 

Mars, ^'"^ 

Jupiter, tp"'  = 

Saturn, <?'  =     2°,7762 

Uranus, <p"  =      0^,8596 


9  =  7°,7778=  7''00™00'; 
9'  =  3°,7701  =  3  23  35  ; 
?"  =      0°  ; 

2°,0556  =      1  51    00 

1°,4636=      1  19  02 

2  29  55 

0  46  25 


Inclina- 
tions of 
the  orbits 
to  the  fixed 
ecliptic  of 
1750. 


[4082] 


Longitudes  of  the  ascending   nodes   on  the  ecliptic  of  the   year  1750,   or 

the  values  of  ô,  6',  ^c. 


Mercury, .  . 
Venus,  . .  .  . 
The  Earth, 
Mars,  .  .  .  . 


=    50^,3836=    45''20™43^; 
==    82°,7093=    74  26   18  ; 

as  in  [4249—4251]; 
'=:    52°,9376=    47  38  38 


Jupiter, «'"=  108°,7846  =    97  54  22 

Saturn, ô'  =  123°,8960  =  111  30  23 

Uranus, r  =    80^,7015  =    72  37  53 

VOL.  III.  48 


Longitudo;^ 
of  tlie 
ascending 
nodes  of 
the  orbits 
on  the  fixed 
ecliptic  of 
1750. 


[4083] 


190 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Epoch.  All  these  longitudes  are  counted  from  the  mean  vernal  equinox,  at  the  epoch 
[4084]  of  December  olst,  1749,  mid-daij,  mean  time  at  Paris.  ^Ve  may  here 
Lpnguude  observe,  that  hij  the  longitude  of  the  perihelion,  is  to  be  understood,  the 
rlôJiT  <^'^fc>^c^  of  the  perihelion  from  the  ascending  node,  counted  on  the  orbit, 
increased  by  the  longitude  of  that  node. 

23.    We  have  obtained  the  following  results,    by  the   formulas  of  §49, 
Book  II. 

MERCURY    AND    VENUS, 


[4085] 


[4086] 


hence  we  deduce 


Then  we  obtain* 


0.  =  -  =  0,53516076; 


6_;.  =  2,145969210; 


rin 


6  \  =  — 0,515245873. 


6^  =  2,1721751  ;  b''^  =  0,6057052  ;  6^^'  =  0,2465877  ; 


,(3) 


^^L.        6,  =  0,1107665; 


,w 


6^  =  0,0520855; 


,(5) 


6V=  0,0251378; 


,(6) 


[4087]  5^  =  0,0123166  ; 


,P) 


6\'=  0,0060633 


(S) 


6^;'==  0,0029287  ; 


6^^'=  0,0012758. 


*  (25G3)    From  a,  a   [4079],  we  have    a=-,      as  in  [4085].     Then  from  [989]. 

[40S6a]     we  find,     6,,    b_^,     as  in  [4086];  from  these  we  get     b<,     b,    [40S7],  by  means  of 

the  formulas  [990,  991].  Then  putting,  in  [966],  s^i,  and  successively,  ?:=-2.  /=3, 
I  =  4,  Sec.  we  obtain  the  remaining  terms  of  [4037].  From  these  last,  we  get  those 
[40866]  in  [40S8],  by  putting,  successively,  2  =  0,  j*  =  l,  Sec,  and  s  =  i,  in  [981].  The 
same  values,  being  substituted  in  [98-2],  give  [4089]  ;  also  [983]  gives  [4090]  _ 
Lastly,  by  taking  the  partial  differential  of  [983],  relative  to  a,  we  shall  get  an  expression 

U) 
d*b  s  ■ 

[4086c]     of  ;      in    which    we    must    put      s  =  i  ;     then     j'^0;     /=1,    &;c.  ;     and  we 

(0)         a) 
shall  get  [4091].      Again,  the  formulas  [99-2]  give     ba. ,     bs. ,    [409:2];  from  these  two 


Vl.vi.S^a.]  VALUES  OF  b'^,  AND  ITS  DIFFERENTIALS  FOR  MERCURY.         191 


(0) 

dbl, 

da. 

=  0,780206  ; 

do. 

1,457891  ; 

dbi 
do. 

=  0,691487  ; 

(41 
dbi 

do. 

0,423818; 

(6) 
dbi 

rfa 

=  0,147708  ; 

a) 
db^ 

do. 

0,085953  ; 

(0) 

dH^ 
da? 

=  2,756285  ; 

(11 
dHi 

da? 

=  2,426165; 

(3) 
d"-bi 

do? 

=  3,381072  ; 

(41 

dHk 
do? 

=  2,826559  ; 

(6) 

dHi 
da? 

=  1,511016; 

(71 

dH>, 
da? 

=  1,014134; 

(01 

dHk 

do? 

=  11,308703; 

m 
dHk 

da? 

-  12,064245  ; 

(31 

da? 

=  14,584366  ; 

(41 
dH^ 

do? 

=  16,067040; 

(61 

dHk 
da? 

=  13,720218. 

(2) 

d*bK 
do.* 

=  69,60594  ; 

(?) 
d^b^ 

da.* 

=  82,36773  ; 

(51 
d*bk_ 

da.* 

=  105,33962. 

r-1 
db.i 

do. 

-  1,070071  ; 

j/^ 

dbi 
do. 

=  0,252376  ; 

[4088] 

77"' 

db^ 
do. 

=  0,050726. 

(21 

dHi 
do? 

=  3,395022  ; 

d^fl 
do? 

=  2,137906  ; 

[4089] 

Mercury 
and  Venue . 

(21 

dHi, 


(51 

dH^ 
da? 


11,983424; 
15,617274; 


(41 

d*b), 


92,72610  ; 


[4090] 


[4091] 


terms,  we  may  obtain  the   others  of  [4092],    by  means  of  the   formula  [966]  ;    putting 

s  =  |,    and,  successively,    i^2,    i=3,    &;c.      The  values  [4093]  are  found  from  [981], 

by  putting  s  =  f,   and    i  =  2,   i  =  3,  he.     Those  in  [4094]  are  deduced  from  [982],  by     [4086d] 

using  similar  values  of  s,  i  ;    observing  to  substitute,  in  any  of  these  formulas,  the  values 

of  b,   or  its  differentials,  which  occur,  and  have  been  found  in  the  preceding  parts  of  the 

calculation.      All  the  other  terms  of  this  article,  §23,  are  found  in  the  same  manner,  except 

those  in  [4113,  4119,  4124,  Sec],  where   a  is  very  small  ;  and  there  is  no  difliculty  in  the      [4086e] 

calculation,  except  the  ennui,  arising  from  a  long  and  uninteresting  numerical  calculation. 


192 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


(!)  (2) 

4,214154  ;      6^  =  3,035376  ;      63  =  1,950536  ; 


[4092] 


Mercury 

and  Venus. 


(3) 


b^=    1,192372; 


2- 


0,238807. 


(4) 

6  ,  =  0,708667  ; 


(5) 

63  =0,413762; 


[4093] 


(2) 


=  12,50630; 


(3) 

^  =  9,76666  ; 

da. 


(1) 
dbî 


7,08399 


(5) 
db^ 

da. 


=    4,88781. 


[4094] 


(3) 

dHi 


=  78,09476  ; 


(4) 

dHi 
da.^ 


67,14764. 


[4095] 


MERCURY    AND    THE    EARTH. 


hence  we  deduce 


a  =  -  =  0,38709812  ; 


[4096] 


,  (0) 


6^;  =2,07565247; 

~2 


,(I) 


6  ,  =  —0,37970591. 


Then  we  get 

Mercurjr 
and  the 
Earth. 

6*^"'  =  2,081980; 

(1) 

6,  =0,411140; 

2 

è'f  =  0,120178  ; 

[4097] 

(3) 

6^  =  0,038900  ; 

(4) 

6  J  =  0,013202; 

ô'J  =  0,004603  ; 

(6) 

6    =  0,001629  ; 

(V) 

6^  =0,000573; 

(8) 

b,  =0,000177. 

VI.  vi.§:2;3.]  VALUES  OF  T'  AND  ITS  DIFFERENTIALS  FOR  MERCURY.         193 


(0) 

da. 

(3) 

dbj 
do. 

(6) 

dbi 


=  0,464378  ; 


=.  0,316756  ; 


=  0,026130  ; 


(0) 

cPbj 
da.' 

(3) 

dH^ 
da.^ 


(2) 

dHj 


,(0) 


=  1,672199; 


=  1,852364; 


=    6,49232; 


6    =2,871833; 


6*''  =  0,334212  ; 


(I) 
db), 


(4) 

dbj 
do. 

m 
dbj 

da. 


(1) 
d^bi 


(4) 

dHj_ 
do.^ 


(3) 

dHj 
da.^ 


.(') 


1,199633; 
0,141792; 
0,011153. 

1,220775; 
1,197245; 

:    5,45663; 


63  =1,576062; 


,w 


63  =0,153779. 


(2) 

dbj 

do. 

(5) 
dbis 

da. 


0,665739  ; 
0,061433  ; 


[4098] 


(2) 

'^l^^  =  2,235935  ; 

do.^ 

(5) 

'^^J^  =  0,670874. 

[4099 

Mercury 
and  the 
Earth. 

(4) 

^'^^  _    6,51373. 

[410C 

6^!' =  0,747619; 

(3) 
dbi 


=  3,05535. 


[4101] 


[4102] 


MERCURY    AND    MARS. 


hence  we  deduce 


a  =  ^,  =  0,25405312  ; 


,(0) 


b'^  =  2,03240384  ; 


,  (1) 


r:  =  — 0,25198657. 


[4103] 


Mercury 

and  Mare. 


[4104] 


VOL.  III. 


49 


194 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


Then  we  have 


[4105] 


Mercury 
and  Mars. 


[4106] 


[4107] 


b^'^  =  2,033500  ; 


,(3) 


(0) 


,(1) 


dbl 


do. 
do. 


(0) 


(3) 
d^bj 

doJ" 


=  1,050458. 


b    =0,260462; 


,(2) 


6  J  ==0,049765; 


(5) 


=  0,010546; 

'.= 

=  0,002331  ; 

b  ^  =  0,000538. 

=  0,273829  ; 

(1) 
dbi 

d  a 

=  1,077839; 

ir^  =  0,402980  ; 
do. 

=  0,127139  ; 

db^ 
do. 

=  0,037781. 

=  1,244725; 

do? 

=  0,656780  ; 

(3) 

^=  1,778641  ; 

[4108]  è^J^=  2,322536; 


,(1) 


rJ  =  0,863876  ; 


6'''  =  0,272085. 


[4109] 

Mercury      hcncc  WB  deduce 

and 
Jupiter. 


[4110] 


MERCURY    AND    JUPITER. 


a  =  -  =  0,07442555  ; 

a" 


f^  =  2,00277053  ; 

2 


&";  =  —  0,07437397. 


,(0)  ,(1) 


In  computing  the  values  of  6  ,  6  ,  &c.,  by  means  of  the  formulas 
[966 — 983],  it  is  found,  that  the  successive  terms  of  the  series  become 
more   inaccurate,  particularly  if  o.   be   rather  small  ;    because  these   values 


Vl.vi.  §23.]    VALUES  OF  b^^  AND  ITS  DIFFERENTIALS  FOR  MERCURY.         195 

are  the  differences  of  numbers,  Avhicli  vary  but  little  from  each  other  ;  so 
that  we  are  under  the  necessity  of  computing  them  to  an  extreme  degree  [4lll] 
of  exactness,  to  enable  us  to  determine  correctly  their  differences,*  and 
this  requires  the  use  of  tables  of  logarithms  to  ten  or  twelve  places  of 
decimals.  To  obviate  this  inconvenience,  we  may  have  recourse  to  the 
value  of  b  '\  developed  in  a  series,  by  means  of  the  formulas 
[976,  984— 985],t 

'ill   (i±i'  a2J_*-(*+l)  (^+')-(^-H+l)  ^4 

*-=^-—     172737^::^^ — •"-'•< ^    [4112] 


1.2.3        •    (i+l).(i+2).(i+3)   •    "^ 

This  value  of  6'"'  is,  in  the  present  case,  very  converging,  on  account 
of  the  smallness  of  a.  We  shall  hereafter  use  it,  in  finding  the  values  of 
b    ,      b  \    &ic.;       6'°\      &c.,     in    ail    cases    where     a     is    rather   small. 

i  h  ^ 

By  this  method  we  have  computed,  for  Mercury  and  Jupiter,  the 
following  values  ; 

(0)  (1)  (2) 

6    =  2,002778  ;  b,=  0,074581  ;  6,  =  0,004164  ;  [4113] 

Mercury 
(3)  (4)  and 

b^  =  0,000258  ;  b^  =  0,000017.  '"•'''"• 

*  (2564)    Thus,  if  we  put     s  =  i     and     i  =  2,     in  [966],  it  becomes 

<i)  (0) 

(2)       (l+a').6a— ia.è  ,  [4111a] 

**  = f^ —^  • 

Now      ht,     is  much  smaller  than       h.       or     h.      [4105],  and  the  preceding  value  of 

b'     is  divided  by  the  small  quantity    J  a.      Hence  it  necessarily  follows,  that  the  terms 

(1  +  a^)  .b,       and     —  ^  a .  è  ,  ,     in  the  numerator  of  this  expression,  must  be  very  nearly 

equal  to  each   other;    and   their  difference,  which  is  to  be  divided  by  a  quantity  of  the     r^mii 

order  a,  must  therefore  be  very  accurately  computed.      The  same  takes  place  in     b\,  &.c. 

t  (2565)    The  quantity     h      is  the  coefficient  of    cos.  i  ê,    in    a-^  [976]  ;    and  X-*  is 
the  product  of  the  two  factors  [985].      If  we  multiply  these  factors,  and  retain  only  terms 
of  the  form     0=*='^*^,      putting     c'"^-' +c-'^»^"' =  2.cos.i é    [12]  Int.,   it  becomes     [4n2„j 
as  in  [4112]. 


196 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4114] 


Mercury 

and 
.lupiler. 


[4115] 


(0) 
dbs 

d  CL 

da. 


m 
dUi 


0,074891  ; 

:  0,010428; 

1,018876; 


Cl) 

dbj_ 
da. 


dHj 
da.^ 


1,006269; 


=  0,171781 


(2) 

dbi, 
d  a 


(2) 

dHj_ 
do.^ 


0,111380; 


=  1,499780; 


[4116] 


6^  =  2,025143  ; 


b'l  =  0,225613  ; 


,(2) 


0,020984. 


MERCURY   AND    SATURN. 


hence  we  deduce 


[4117] 


[4118] 


^Zr     Then  we  find 

Saturn. 

,(0) 


[4119] 


6  j'=  2,000823: 


6^^^  =  0,000042  ; 


0.  =  -  =  0,04058547  ; 


6^°'  =  2,00082368  ; 
6^''  =—0,04057711. 

—2 


6^^  =  0,040610; 

2 

6'^  =  0,000001. 


,(2) 


6^^^=0,001236; 


[4120] 


[4121] 


rf&è 
da. 

=  0,040662  ; 

(1) 
dbi 

da. 

1,001841  ; 

(3) 

dhh 
da. 

=  0,003085. 

(0) 

dH^ 
da.^ 

=  1,003904; 

d< 
da.^ 

:^  0,091840; 

(2) 
dbj^ 

da. 


=  0,060919  ; 


(2) 

dHi 


1,469188. 


VI.vi.'§23.]    VALUES  OF  b'^  AND  ITS  DIFFERENTIALS  FOR  VENUS.  197 


MERCURY    AND    URANUS. 


hence  we  deduce 


a=  4- =  0,02017895; 
a" 


6_\  =  2,00020360; 

6!1',  =  — 0,02017792, 

Then  we  find 

6^^*=  2,000182; 

6^''=  0,020183; 

(0) 

(1) 
020196:              ^^^  =1 

(2) 


è^'=  0,000306; 


do. 


do. 


=  1,000913. 


[4122] 


[4123] 


Mercury 

and 
Utanuf. 


[4124] 
[4125] 


VENUS    AND    THE    EARTH. 


hence  we  deduce 


«L  =  ^,  =  0,72333230  ; 

a 


6  ,  =  2,27159162; 

—  3 

Then  we  obtain 

6  ''!  =  —  0,672263] 

(0) 

b^  =  2,386343  ; 

b'^  =  0,942413  ; 

(3) 

b.  =0,323359; 

6*"  =  0,206811  ; 

6  J  =  0,090412  ; 


▼OL.   III. 


.cn 


60 


6^  =0,527589; 

2 

6^  =  0,135616; 


(8) 


6i  =  0,061101  ;  6^  =  0,041731. 


[4126] 


[4127] 


Venus 
and  the 
Earth. 


[4128] 


198 


[4129] 


[4130] 


Venus 
and  the 
Earth. 


[4131] 


[4133] 


[4133] 


(0) 

db^ 
do. 

(3) 
djb^ 

do. 

(6) 

dbj 
d  a 


(0) 

dH^ 
do.^ 

(3) 

dHj 
do.^ 

(6) 

do.^ 

(0) 

do.^ 

(3) 
d^ 

do.^ 


,  (0) 


PERTURBATIONS  OF  THE  PLANETS  ; 

:  1,643709; 
1,738781;" 
0,867147  ; 

7,719923  ; 

9,112527; 
:  7,842733. 

:  66,55335  ; 
:  62,87646  ; 


[Méc.  Cél. 


63  =  9,992539  ; 


,(3) 


b,  =  6,953940  ; 


K3) 

d_H_ 

do. 


(I) 

dbi 

do. 

=  2,272414; 

(2) 

dbi 
do. 

:  2,069770  ; 

(4) 

do. 

:  1,407491  ; 

(5) 
db^ 

do. 

=  1,113704; 

df^ 
do. 

:  0,668830. 

do.^ 

=  7,531096; 

(2) 
d^fii 

do? 

=  8,558595  ; 

(4) 
d^i 

:  9,107400  ; 

(5) 

dn^  _ 

/7«2 

=  8,634030; 

d^èl 


do.^ 

(4) 

dH^ 
do.^ 


=  57,35721  ; 


66,32409  ; 


,(i) 


Ô;  =  8,871894; 


rt^) 


b\  =  4,704321  ; 


=  56,65440  ; 


(4) 

dbi 
do. 


(2) 


dHi 


=  58,19633; 


dH 


(5) 


da» 


i  =  70,54326. 


,(2) 


6  y  =  7,386580  ; 


6  ;  =  3,652052. 
50,90290. 


VENUS   AND    MARS. 


[4134] 


Venus 
and  Mars. 


[4135] 


hence  we  deduce 


a  =  4;  =  0,47472320  ; 

a 


6^°J=  2,11436649; 
6"j  =  —  0,46094390. 


VI.  vd.^SS.]     VALUES  OF  i^;'  AND  ITS  DIFFERENTIALS  FOR  VENUS.  199 

Then  we  find 


67=2,129668; 

S 


5^  =  0,521624; 

3 


fe'f  =  0,187726; 

5 


6*^'  =  0,074675  ; 


6*^'*  =  0,031127; 


6'f  =  0,013337;  [4136] 

2 


(6) 


6 ,  =  0,005829. 


dh 


(0) 


do. 

(3) 


1  =  0,631752; 


^  =  0,510976; 

do. 


(0) 


^  =  2,192778; 

do.- 


(3) 

dHh 
do? 


=  2,628516  ; 


(0) 

dH^ 
do? 

(3) 

dHi, 
da? 


7,65440  ; 


=  10,66513. 


(1) 

db^ 
do. 

1,330781  ; 

do. 

0,279002  ; 

(1) 
dH^^ 

do? 

--  1,815836; 

do? 

=  2,004429. 

J    .3 

=  8,45655  ; 

do? 


(2) 

dh^ 
do. 

(5) 

db^ 
da. 


(2) 

d^i 
do? 


0,884106  ; 
0,147606. 

=  2,795574  ; 


i^  =  8,17676  ; 


[4137] 


[4138] 


VonuB 

and  Mars. 


[4139] 


,(0) 


6    =  3,523572  ; 

2 


.<3) 


6,  =0,722687. 


6*3^  =  2,304481  ; 


(2) 

dH 
da. 


8,47521. 


.(2) 


&3  =  1,325959; 


[4140] 


[4141] 


VENUS   AND    JUPITER. 


a=-  =  0,13907116; 


VenuB  and 
Jupiter. 

[4142] 


200 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


hence  we  deduce 


[4143] 


b^'l  =  2,00968215  ; 
6''' =  —  0,13873412. 


Then  we  have 

6^  =  2,009778; 

6'^'=  0,140092; 

6'J'=  0,014623; 

[4144] 

6^^=0,001695; 

f4) 

6^  =  0,000206; 

(5) 

6^  =  0,000026. 

Venus  and 
Jupiter. 

2 

[4145] 

\^  =0,142160; 

a  a 

^=1,022206; 

da 

-^  =  0,212046  ; 

da                              ' 

dh 

'^  "*  =  0,036783  ; 
d  0. 

"/*  =0,006111. 

da 

rdi  /irfîi 

(0) 

^=1,067532; 

(1) 

Ç^=  0,325869; 

(2) 

'^^*_  1,575190; 

[4146] 

(3) 

'^l^^  -0,533951. 

[4147] 

C) 

63  =2,089736; 

(1) 
b^  =  0,432801  ; 

(2) 

63=  0,075054. 

VENUS    AND    SATURN. 


[4148] 


Vennsand      hcHCe  WC   dcduCC 

Saturn. 


[4149] 


a  =  -  =  0,07583790  ; 


b^^  =  2,00287673  ; 
b^'\  =  —  0,07578334. 


,w 


Vr.vi.§23.]    VALUES  OF  b'J  AND  ITS  DIFFERENTIALS  FOR  VENUS. 


201 


riieii  we  obtain 

(0) 

6j  =  2,002886  ; 

(1) 

=  0,076002  ; 

(2) 

-.  0,004323  ; 

[4150] 

6^'  =  0,000273  ; 

2 

'*: 

=  0,000018. 

[4151] 

(0) 

''f  *  =  0,076331  ; 

da. 

(1) 

dbi, 
do. 

=  1,006490; 

(2) 
dbi     _ 

da. 

0,114267; 

[4152] 

7/'" 

,*   -0,011085. 

da 

Venus  anil 
Saturn. 

(0) 

''^=1,019629; 

ft  a.-' 

d^i 
da? 

=  0,172510; 

(2) 

dHi 
do? 

1,419950. 

[41.53] 

(0) 

b\  =2,026116; 

!>":- 

^ 

=  0,229988  ; 

=  0,021791. 

[4154] 

VENUS    AND    URANUS. 


hence  we  deduce 


Then  we  find 


a  =  —  =  0,03770634  ; 


r\  =  2,00071095; 


-'2 


—  0,03769964. 


[4155] 


[41.56] 


Venu3  and 
Uranus. 


,(0) 


0^=2,000712; 


,(1) 


6^=0,037725; 


,(2) 


b\=  0,001067  ;  [4157] 


,0) 

4 


67  =  0,000034. 


(0) 

dbi 


da. 
VOL.  Ill 


=  0,716690  ; 


(1) 
dbj 

da. 


=  1,000829; 


51 


(2) 

db  i 
do. 


=  0,056634. 


[41.58] 


202 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


THE    EARTH    AND    MARS. 


[4159] 


[4160] 


a  =.  —  =  0,65630030  ; 


hence  we  deduce 


Then 


[4161] 


The  Earth 
and  Mnrs. 


[4169] 


[4163] 


[4164] 


.(0) 
(3) 
(6) 

6,  = 


(0) 

da. 

(3) 


(6) 

da. 


(0) 


(3) 

dHj 
do.^ 

(6) 

dH^ 
do? 


(0) 

dHh 


do.^ 

(3) 

dH^ 


2,291132; 
0,224598  ; 
0,046595  ; 

=  1,228078; 

:  1,240990; 
:  0,473942  ; 

4,985108  ; 

6,057860  ; 
:  4,388001. 

29,03400  ; 

33,29381  ; 


,  (0) 


6_j  =  2,22192172; 


,(") 


6_^  =  _  0,61874262. 


=  0,804563 , 

a'^' 

h 

=  0,129973  ; 

0) 

=  0,028480  ; 

(1) 

dbh 
do. 

=  1,871211; 

(4) 

d  b  ^ 
do. 

^  0,920710  ; 

7  7^" 

db^ 
do. 

=  0,333444. 

(1) 
dn^ 

do.^ 

=  4,744671  ; 

(4) 

d^bi 

.1    .2 

=  5,776483  ; 

(I) 
^  =  29,78930  ; 

(4) 

d^bi 

Vf-  =  36,32093  ; 


(SJ 


h- 

=  0,405584  ; 

(5) 

=  0,077170; 

2 

:  0,0175565. 

1,601236; 

(5) 
,7  „ 

=  0,666207  ; 

(2) 

dH^ 
do? 

(?) 
dHk 


=  5,731111 


5,141993; 


(2) 


îÇii.  =  30,18848; 


(5) 

dH), 


=  37,23908. 


VI.  v-i.  §-23.]  VALUES  OF  ù^'^  AND  ITS  DIFFERENTIALS  FOR  THE  EARTH.        203 


(0) 


6  y  =  6,856336  ; 


6'''  =  3,255964  ; 
6^''  =  1,174650. 


(2) 

^  =  31,80897; 
do. 


,(') 


J  3  =  5,727893  ; 


fi'I'  =  2,351254  ; 


f^  =^  4,404530  ; 


6'^'  =  1,671668; 


[4165] 


(3)  (5) 

'^  =  32,26285  ;    ....   'Ill  ^  18,25867.  [4166] 

a  a  «a 


THE    EARTH    AND    JUPITER. 


hence  we  deduce 


Then 


6^  =  2,018885; 
6^^'=  0,004516; 


,(6) 


a=  -  =  0,19226461  ; 


&'"[=  2,01852593; 
6^'!  =  —  0,19137205. 


6^  =  0,195003; 

2 

6'^'=  0,000779  ; 


,(2) 


6^=0,028195; 

(5) 

6^  =  0,000132; 


[4167] 


[4168] 


The  Earth 
and 
Jupiter. 


[4169] 


6,  =0,000023. 


(3) 


0,200586  ; 


=  0,070932  ; 


d  a 
da. 


1 ,043204  ; 
0,016369; 


(2) 

da. 


(5) 


0,297995  ; 


=  0,003448  ; 


[4170] 


204 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Ct 


[4171] 


(0) 

dHi, 


1,132355; 


=  0,746681. 


The  Earth  d  0? 

and 
Jupiter. 

(0) 

[4172]        1!^  =  1,4727 14; 


(1) 
d^bi 


=  0,466165; 


Vf  =  2,874986  ; 


(2) 

dH^ 
do? 


1,628667; 


(2) 

^  =  1,418830. 


[4173] 


,(0) 


6  '  =  2,176460; 


(3) 


h  3  =  0,032493. 


6*''  =  0,619063; 

5 


,(2) 


b     =0,148198; 


[4174] 


THE    EARTH    AND    SATURN. 


hence  we  deduce 


a  =  -  =  0,10484520  ; 


(0) 

b_^  =  2,00550004  : 


[4175] 


(1) 


6_  J  =  —  0,10470094. 


Then 


The  Earth 
and 
Saturn 

^'I' 

=  2,005535  ; 

[4176] 

6? 

'S 
(0) 

dbi, 
d<x. 

=  0,000724  ; 

=  0,106155; 

[4177] 

(3) 

dbi 
do. 

=  0,020779. 

fe'l'^  0,105283; 
s 

(4) 

b,  =  0,000066. 


dJl 

d  Ol 


=  1,012536; 


,(2) 


b    =0,008282; 


(2) 

dbi 


0,158723; 


Vl.vi.§-23.]  VALUES  OF  6*;'  AND  ITS  DIFFERENTIALS  FOR  MARS. 


205 


(0) 


(0) 


1,037816; 


b     =  2,050321  ; 


^  0,246193  ; 

do? 

:  1,526303, 

(1) 

(2) 

b        : 

1 

=  0,321144; 

*,= 

=  0,041977 

[4178] 


[4179] 


THE    EARTH    AND    URANUS. 


hence  we  deduce 


a  =  -=0,05212866; 


[4180] 


,  (0) 


6  ;  =  2,00135893; 
-i 


.0) 


6_^  =  — 0,05211095. 


[4181] 


Then  we  find 


.  (0) 


b     =2,001355; 


.0) 


6-  =  0,000089. 

2 


(1) 


6    =0,052182; 


6^=0,002040; 

2 


The  Earth 

and 
Uranus. 


[4182] 


(0) 

dbi 

~  =  0,052288  ; 


-(0 


da. 


'  -  1,003060; 


(2) 

'^  =  0,078449. 

o  a 


[4183] 


MARS    AND    JUPITER. 


a  =  —  =0,29295212. 


[4184] 


VOL.  III. 


52 


206 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


hence  we  deduce 


[4185] 


Then 


(0) 


b  i=  2,04314576; 


(1) 


&  ,  =  —  0,28977479. 


'r 

=  •2,045112; 

b'^=  0,302922  ; 

2 

<- 

:  0,066812; 

[4186] 

2 

=  0,016357; 

(4) 

6^=0,004192; 

"h 

0,001109; 

"> 

=  0,000297  ; 

(7) 

6^  =  0,000081. 

(0) 

dbi 
da. 

=  0,324004  ; 

0) 

,^  -1,105998; 
do. 

C2) 

do. 

=  0,473717; 

[4187] 

(3) 

db^ 
da. 

=  0,172096; 

(4) 

'^Z*  =0,058420; 
a  OL 

db'l 

-  0  019258: 

do. 

Mara 

and 

Jupiter. 

(6) 
dbh 

do. 

=  0,006173. 

(0) 

dHi 
do.^ 

=  1,338759; 

3.  m 
^  =  0,794557  ; 

(2) 

do.^   ' 

=  1,871538  ; 

[4188] 

(3) 

do.'' 

=  1,258858; 

(4) 

'^'\*- 0,623184. 

(0) 

d^bi 
do.^ 

=  2,69358  ; 

^  =  3,77722  ; 

(2) 

=  2,91068; 

[4189] 

(3) 

dHi 
do.^ 

=  5,47068. 

(0) 
*3     = 

=  2,444762  ; 

6  '=1,040206; 

3 

:  0,376693; 

[4190] 

'b% 
i 

=0,127942. 

^ 

VI.  vi.§23.]    VALUES  OF  6"'  AND  ITS  DIFFERENTIALS  FOR  MARS. 


207 


(0) 

db^ 
da. 


=  3,48815  ; 


(I) 
db^ 


do. 


=  4,80540  ; 


(2) 

^  =  2,99684. 

a  a 


[4191] 


MARS    AND    SATURN. 


a  =  —  =  0,15975187; 


[4192] 


hence  we  deduce 


Then  we  find 

(0) 


(3) 


6_  1  =  2,01278081  ; 


6^'^  =—0,15924060. 


(0)  (1)  (3) 

6,  =2,012945;  6,  =0,161305,  6,  =  0,019347  ; 

-  2  2 


w 


h- 

=  0,002577  ; 

=  0,000360  ; 

(0) 

dbi 
do. 

=  0,164463; 

(1) 

dhi    . 
da. 

=  1,029493; 

dbi 
do.    ~ 

=  0,048740  ; 

do. 

=  0,009065. 

(0) 

dHi 
do? 

=  1,090095; 

(1) 
dHi 

da? 

-  0,379322  ; 

(3) 

-  n  fi9nfi.S9 

(5) 


b^  =  0,000052. 


(2) 

dbi 


0,244843  ; 


(2) 

Ç^  =  1,596248; 
da.-' 


[4193] 


[4194] 


Mars 
and 
Saturn. 


[4195] 


[4196] 


da? 


,  !0) 


6;  =  2,119585; 


b'l'  =  0,503071  ; 


,(2) 


6y  =  0,100136;  [4197] 

2 


208 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél 


MARS    AND    URANUS. 


hence  we  deduce 


[4198] 


[4199] 


Mars       Then  we  find 

aod 
Uranus. 

,(0) 


[4200] 


6^  =  2,003167; 


,  C3) 


a  =  -  =  0,07942807  ; 

a"' 


5'°^  =  2,00315565  ; 
f\  =  —  0,07936538. 

—5 


6'"  =  0,079617; 


(4) 


6V  =  0,000314  ;  b.=  0,000022 

2  2 


,(2) 


6^=0,004746; 


[4201] 


(0) 

da. 

(3) 

d_H 
d  a. 


0,079995  ; 


0,011982. 


(1) 
dbk 


=  1,007144<; 


(2) 

dH 
da. 


=  0,119822: 


JUPITER    AND    SATURN. 


[4202] 


Jupiter 

and 
Saturn. 


[4203] 


a  =  -  =  0,54531725; 

a" 

hence  we  deduce 

(0) 

6_j  =2,15168241; 

felj=  — 0,52421272, 

Then  we  have 

6^^'  =  2,1802348; 

6*''  =  0,6206406  ; 

•3 

b'^  =  0,2576379  ; 


VI.  vi.§^3.j    VALUES  OF  i'j'AND  ITS  DIFFERENTIALS  FOR  JUPITER. 


209 


(3) 


bi  =0,1179750; 


(6) 


5,  =  0,0139345  ; 


,(9) 


èy=  0,0018056; 

2 


b^  =0,0565522; 

(7) 

b  .  =  0,0070481  ; 
6*J"L  0,0008632  ; 


6,  =0,0278360; 

(8) 

6^  =  0,0035837  ; 


bl'L  0,0003223. 


[4204] 


77'"' 

db  i 
da. 

=  0,808789  ; 

(3) 
db^ 

da. 

=  0,726550  ; 

(6) 

dbi 
da. 

=  0,163506; 

(9) 

=  0,033083  ; 

(0) 

-  2.875229  : 

da.^ 


(3) 


'^^  =  3,533622  ; 


dHi 

do? 


=  1,664586; 


(9) 

^  =  0,485135. 

da? 


da. 

(4) 
(7) 

da. 

(10) 

db  i 


(1) 
dHj 

do? 

(4) 

dH^ 
da? 


=  1,483154; 


=  0,453285  ; 


0,096019  ; 


0,020265. 


2,552788 


(7) 

dH^ 
1^ 


=  2,995647  ; 


=  1,144377; 


(2) 
db^ 


=  1,105160; 


(5) 
db^ 


(8) 

dbi, 
da. 


0,274717; 


=  0,056171  ; 


(2) 


da? 

(55 
dH}, 

da? 

(8) 
d^b^ 

d  a' 


=  3,521040; 


=  2,302428  ; 


i  =  0,760603  ; 


[420.5] 


Jupiter 
and 
Saturn. 


[4206] 


(0) 

da.^ 


12,128630  ; 


(3) 


dH,, 


=  15,454850  ; 


d^bk 

~~  =  14,958762  ; 

VOL.  III. 


(I) 
dHj 

da? 


=  12,878804; 


(4) 

^1^  =  17,058155; 
Vf=  12,234874; 


53 


(9) 


(Z^èj 


=  12,832050; 


(5) 

dHk 


(8) 


=  16,655445;        [4207] 


,  ,   =  9,566420. 


210 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4208] 


(0) 

d^hi 


(?) 
d*bi^ 


84,40159  ; 


=  89,8615; 


(6) 

dHi 


118,6607; 


(1) 
d*bi 

do} 

(4) 

d'bi, 


da.* 

(7) 

da." 


=  83,94825  ; 


101,3809; 


=  115,9588. 


(2) 

d'bk^ 

—  87,3027  • 

da.* 

(5) 

dH^ 
da." 

=  113,5238; 

[4209] 


Jupiter 

and 
Saturn. 


[4210] 


d'b^ 
da.^ 


(1) 


=  747,480  ; 


dH 


(3) 


d  a: 


I  =  785,884  ; 


(6) 

^—^  =  912,301. 

da."- 


f^  =  4,358387  ; 


6''' =  1,295672; 


6^"  =  0,273629  ; 


b'^  =  0,053922. 

3  ' 


d^bi 

da.' 

(4) 

dHi 

(3) 


da.^ 


=  753,417; 


=  819,180; 


6^^^  =  3,185493; 
z 


f^  =  0,784084  ; 


67  =  0,158799; 

2 


d' 

H 

d 

a5 

d^ 

(5) 

761,843: 
■■  884,505  ; 


(2) 


b    =  2,082131  ; 


,(5) 


63  =0,466047; 


(8) 


b  ,  =  0,092290  ; 


[4211] 


(0) 

^  =  14,681324; 

da. 

^=10,598611  ; 

d  a 


db 


i  =  3,710043  ; 


(1) 
db$ 

da. 


(.1) 
dbj 

da. 


(7) 
db§ 

d  a 


15,239657  ; 

7,802247  ; 
:  2,426079  ; 


(2) 

^=13,416026; 


(5) 

db§ 
da. 


=  5,470398  ; 


(8) 


1^^=1,563695. 

a  a. 


(0) 


dHj 
da.^ 


=  96,68536  ; 


(I) 

^2/,;t 

VI- =  94.91 701; 

d  a.-' 


(2) 

Vf  =  93,19282; 


VI.  vi.§'23.]    VALUES  OF  li^"  AND  ITS  DIFFERENTIALS  FOR  JUPITER.  211 


(3) 

dHè 

d<x? 

(«) 
dH^ 

da? 

(0) 

d^i 

do? 

(3) 

dH§ 

do? 

(6) 

dHi 

da? 


=  86,90215  ; 


=  47,48185; 


830,0586  ; 


785,5855  ; 


=  574,9115. 


(4) 

ll/f=  75,08115; 


dHi 
do? 


35,74355. 


do? 


=  830,1580  ; 


(4) 

d^b3- 

Vf  =  740,6775  ; 

do." 


(5) 

d^b§ 
do? 


=  61,10115; 


dH§ 

do? 


=  810,1045; 


(5) 

d^b^ 

Vf  =  666,4080  ; 

do? 


[4212] 


Jupiter 

and 
Saturn. 


[4213] 


JUPITER    AND    URANUS. 


hence  we  deduce 


Then  we  get 

6^°'  =  2,038359  ; 

S 

6^  =  0,012879  ; 

2 

(6) 

6,  =0,000185. 

do  4 


a  =  —  =  0,27112980; 
a" 


6'"!  =  2,03692776  ; 


6l'!  =  — 0,26861497. 


6'''  =  0,278966  ; 


ft'"'  =  0,003058  ; 


da. 


=  0,295410; 


dix. 


=  1,089551; 


6 ,  =  0,056906  ; 
6^^^  =  0,000745  ; 


(2) 

da. 


[4214] 


[4215] 


Jopiter 

and 
Uranus. 


[4216] 


=  0,433630  ;  [4217] 


212 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Jupiter 

and 
UranCB. 

(3) 

^,^  -  0,145398  ; 

a  a 

Ç^=  1,283434; 
da'' 

[4218] 

(3) 

'^'\*  =1,133359. 

da'' 

(0) 

b  3  =  2,372983  ; 

[4219] 

2" 

6 ,  =0,099260. 

(4) 

da 


rf^tT 


=  0,045930  ; 


=  0,714932  ; 


(1) 


b    =-0,938794; 


(5) 

dbi 


da. 


(2) 
dHi 

da? 


0,015410. 


1,815451  ; 


6  "'=0,315186; 

3 


[4220] 


hence  we  deduce 


SATURN    AND    URANUS. 


a  =  —  =0,49719638; 
a"' 


(0) 

b  1=2,12564287; 


[4221] 


(1) 


b  i  =  — 0,48131675. 


Saturn 

and 

Uranus. 


Then  we  get 


(0) 


6,  =  2,144440; 


(') 


6^  =  0,552007  ; 


(2) 


6    =0,208313; 

2 


(3) 


[4222]  6^=0,086834; 


(4) 


6    =0,037909; 
i 


(5) 


0^  =  0,016990; 


(6) 


6 ,  =  0,007728  ; 


(V) 


6    =0,003522; 
i 


.<8) 


6     =0,001547. 

2 


(0) 
dh  1 

^  =  0,683055; 

da 


db. 


(1) 


=  1,373806; 


(2) 

1^=0,949128; 
da 


,(i) 


Vl.vi.  ^v,>3.]  VALUES  OF  bj  AND  ITS  DIFFERENTIALS  FOR  SATURN. 


213 


(3) 

i^A  =  0,572896  ; 
do. 


(6) 
dbl 


=  0,098799  ; 


dbj 

da. 

(7) 
dbi 

do. 


=  0,327198; 


0,053642. 


(5) 
dbj 

da. 


0,181370; 


[4223] 


(0) 

"  1^  =  2,377102; 


=  2,881218; 


d 

a.-2 

d°~ 

(3) 
'b^ 

d 

0.^ 

d^ 

(6) 

H 

d 

0.^ 

rf3 

(0) 

d 

a? 

J3 

(?) 
bi 

do? 


rC) 


1,067430. 


=  8,798999  ; 


=  11,904140; 


6;  =  3,750905; 


(3) 

b     =0,872105; 


d^bj 

do!^ 

dn\ 


=  2,017767; 


=  2,278077  ; 


(1) 

d  0? 


9,578267  ; 


d^b^ 

--^=  12,988670; 
do."* 


f^  =  2,547992  ; 
6^'J  =  0,482564  ; 


(2) 
d^bi 


=  2,992245  ; 


(5) 


d^J. 


=  1,616470; 


(2) 

do? 

9,425450  ; 

(5) 

12,135721. 

"> 

=  1,530452; 

(5) 


b    =  0,262146. 


[4224] 


Saturn 

and 

Uranu». 


[4225] 


[4226] 


(2) 

^=9,75656; 

do. 


(3) 
db^ 

-P  =  7,24097  ; 

da. 


(4) 


'iH  ^  4^95062. 
do. 


[4227] 


YOL.   III. 


54 


214  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Ctl 


CHAPTER   VU. 

NUMERICAL  EXPRESSIONS  OF  THE  SECULAR  VARIATIONS  OF  THE  ELEMENTS  OF  THE  PLANETARV  ORBITS. 

24.     We  shall  now  give  the  numerical  values  of  the  secular  variations  of 

the  elements  of  the  planetary  orbits.     For  this  purpose  we  shall  resume  the 

differential  variations  of  the  excentricities,  perihelia  and  inclinations  of  the 

îbVthe"'    orbits  ril22,  1126,  1142,  1143,  11461.     To  reduce  these  formulas  to  num- 

computa-  L  '  '  '  '  J 

(oln^Lc.  bers,  we  must  previously  determine  the  numerical  values  of  the  quantities 
(0,1),  [^J],  &c.  These  are  obtained  by  computing,  in  the  first  place,  the 
values  of  (0,1),   [ÔJ]  ;  by  means  of  the  formulas  [1076,  1082],* 

(1) 
.  _  1  ,  3  m.  n  a? .  b_i 

[4^8]  CQ'^)=-4.(l-a^)^ 


I'onnHlas 


14228']  [JM  ]  = o    n_.2^a 


(1)  (D) 

3m'. no..  I  (l+a^).6_^  +  Aa.6_è  \ 

2.(l-a2)2 


From  these  we  have  deduced   the  values  of  (1,0)   ["iT|,  by  means    of  the 
equations  [1093,  1094]. 


(0)        U) 

*  2566.  The  values  of  mf,  n,  a,  b_i,  6_j  to  be  used  in  tliese  formulas  are  given  in 
IA09R  [4061  —  4222].  By  the  formula  [4228]  we  must  compute  the  values  corresponding  to 
the  exterior  planets,  namely  ;  (0,1),  (0,2),  (0,-3),  (0,4),  (0,5),  (0,6);  (1,2),  (1,3),  (1,4), 
(1,5),  (1,6);  (2,3),  (2,4),  (2.5),  (2,6);  (.3,4),  (3^),  (3,6);  (4,-5),  (4,6);  (5,6);  and  the 
similar  ones  of  [4228'],  namely;  [J^]  Sic;  [wi]  &ic.  ;  [W]  fee;  [J±]  &lc.;  [JJ] 
he;  [Jfi^j.  The  remaining  terms  corresponding  to  interior  planets  are  to  be  deduced 
from  these  by  the  formulas  [4229].  Thus,  if  it  be  required  to  compute  (4,5),  [^]  cor- 
responding to  the  action  of  Saturn  upon  Jupiter.     The  value  of  m'  to  be  used  in  [4228], 


[42286] 


VI.vii.^^24.] 


SECULAR  VARIATIONS  OF  THE  ELEMENTS. 


215 


(1,0) 


m  .\/a 


7-(0,i); 


m.\/a    ^  7)1.  y  a 

Bv  this  means  we  have  obtained  the  following  results,  in  seconds,  supposing 
tlie  numerical  characters  0,  1,2,  3,  4,  5,  6  to  refer  respectively  to  Mercury, 
Venus,  the  Earth,  Mars,  Jupiter,  Saturn,  and  Uranus.  The  preceding  masses 
of  the  planets  [AOG],  AOGl d],  hove  been  multiplied  by  1  +  f^j  1  +  f^',  1  +  /') 
&.C.  respectively,  in  order  that  these  results  may  be  immediately  corrected, 
for  any  change  in  the  values  of  the  masses,  tohich  may  hereafter  be  found  ne- 
cessary. 


(0,1)  =  (1  +,a').3",052453 
(0,2)  =  (1  +|/').0%963818 
(0,3)  =  (1  + /") .  0',040631 
(0,4)  =-  (1  +(^'0.1',575473 
(0,5)  =  (1  +  f' )  •  0'>080560 
(0,6)   =   (1  +,^'')-0',001702 


mi  =  (1  +f^').l'',961407 
Ul]   =   (1  +(^").0%457195 

[m]  =  (1  +/-"')-0',012797 
[ÎZ]  =  0  +(^'0•0^  146329 
UKl  =  (1  +H-O-0~',004086 
["îZJ   "=    (1  +(^'')-0''000042. 


[42291 

[42,30] 

[4230'] 


[4231] 

Mercury. 


(1,0)  =   (1  +,a  ).0^422318 

(1.2)  =   (1  +/').7\416280 

(1.3)  =   (1  +|j."').0',148161 

(1.4)  =   (1  +M-'^).  4',  131 166 

(1.5)  =   (1  +f^O-0',207370 

(1.6)  =   (1  +  ,a-) .  0%004354 

(2.0)  =   (1  +,.,  ).0',097574 

(2.1)  =   (1  +a').5',426695 
(2,3)  =   (1  +;^-"').0',432999 


rvi 

= 

(!+/-■■ 

.0,271367; 

i,,.i 

= 

(1  +P- 

/  \ 

6-,  174974; 

[-^1 

= 

(1  +(- 

///\ 

.0',085252; 

iHi 

== 

(1+,- 

v\ 

0',7 16427; 

L^J 

= 

(1+'^- 

V    \ 

0  ,019641  ; 

[ÎZ] 

= 

(1+1^ 

\'i\ 

.  0',000205. 

[^] 

; 

(1  + 1^' 

0',046285  ; 

[IZ] 

= 

(1  +f^ 

\ 

4',5 18397; 

[H] 

= 

(1+f^' 

tl\ 

0',332961  ; 

[4232] 

VcTiua. 


The  Ea  rill. 


[4233] 


is  that  of  Saturn,     ?n'-  =  ^l^  '"•."  ^  [40611,  the  value  of  n  is  that  of    n'"  =  109256'29.3 

3339,40  ^^^  [4^8c] 

[4077];    the  value  of  a    is  0,54.531725,  [4202];   then    we  have     è_à  =  2.15168241, 
b_h  =  -0,52421272   [4203].     Substituting  these  in  [4228,  4228']  we  get  the  values 


of  (4,5),  [i£]  as  in  [4235].     Lastly  the  formulas  [4229]  give  (5,4)  = 


•(4,5); 


[m;]  =  ™'^V^.[T£];   hence  we  obtain    (5,4),    \jr\  as  in  [4236],    using   the  factor     [4228(/] 

1  +(*'"  instead  of  1  + /J.^     In  like  manner  the  other  formulas  [4231  —  4237]  are  to  be 
computed. 


216 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Ctl- 


(2,4)   = 

(i+(^'0- 

6',947861  ; 

[m]  = 

=  (l+^-'o- 

1 ',662036; 

TheEaiih. 

(2,5)   = 

(l  +  p-n- 

0,340441  ; 

[iï]  = 

=  (1  +  ^^). 

0%044514; 

(2,6)   = 

(i+H-^O- 

0',007095  ; 

[ISJ  = 

=  (1  +  ^") . 

0',000463. 

(3,0)  = 

(i+O- 

OSO 18662; 

[m]  = 

=  (1+f^  ). 

0',005878  ; 

- 

(3,1)  = 

(1  +  ^')- 

0',491880; 

[s^]    -. 

==  (M-.'). 

0',283029  ; 

[4234] 

(3,2)  = 

(1+^-"). 

r, 964546  ; 

r^]  = 

=  (1+^"). 

1 ',510657; 

MlTB. 

(3,4)  = 

(i+i^-O- 

14',411136; 

Lm] 

=  (i+^-'O- 

5',2 19092; 

(3,5)  = 

(1+^')- 

0%658341  ; 

[^] 

=  (1+.-). 

0,131041  ; 

(3,6)  = 

(1+^-')- 

0%013436; 

[3,6] 

=  (ï+f"). 

0,001333. 

(4,0)  = 

(l+f^  )• 

0%000226 

lii] 

=  (i+M-  ). 

0',000021  ; 

(4,1)  = 

(1  +  M-'). 

0%004291 

[ÏZ] 

=  (i+,v). 

0',000744  ; 

[4235] 

(4,2)  = 

(1+f^"). 

O',009862 

[4,.] 

=  (i+fx"). 

0',002359  ; 

Jupiter. 

(4,3)  = 

(i+n- 

0,004509  ; 

[i^] 

=  (i+O- 

0',001633; 

(4,5)  = 

(1+pO- 

7%701937 

w^ 

=  (1+,-^. 

5%034195; 

(4,6)  = 

(i  +  i^^O- 

0',096647, 

[ja] 

=  (1+H.^'O- 

0',032446. 

(5,0)  = 

(i  +  (^  )• 

0',000027 

;            [m] 

=  (i+(0- 

0^000001  ; 

(5,1)  = 

(i+f^'). 

0',000501 

;            [  ^'M 

=  (1+.'). 

0',000047  ; 

[4236] 

(5,2)  = 

(1  +  1^."). 

0,001123 

;           [^.^J 

^  (1 +..")• 

0^000147; 

(5,3)  = 

-  (i+O- 

0',000479 

;           [m] 

==  (i+O- 

0',000095  ; 

(5,4)   = 

=  (l+f^-) 

17%90ô446 

;           Ua\ 

=  (l+(^'0- 

11%703495; 

(5,6)  = 

=    0  +!'■')  • 

0,355214 

■                            [.6] 

=  (l+r'.^0- 

0',2 13356. 

(6,0)  = 

-  (i+O 

0',000002 

;               [M] 

=  (]+..)• 

0,000000  , 

(6,1)  = 

=  (1  +  p-') 

.   O',000043 

;           [^] 

=  (1+.-') 

0',000002  ; 

14237] 

(6,2)  = 

=  (1+f^") 

.   0',000096 

;            [^] 

=^  (1 +(■.") 

O',000006  ; 

L  '■'"-"  J 
1 1  rciti  us. 

(6,3)  = 

=  (i+O 

0\000040 

;            [Mj 

=  (i+O 

O',000004  ; 

(6,4)  = 

=  (l+(^") 

0%919814 

U±\ 

=  (l+(^-0 

O',308803  ; 

(6,5)   = 

=  (1+^0 

1 ',454 176 

;         un 

=  (1+f^') 

0^873434. 

[4237 


25.  By  means  of  these  values  and  the  formulas  [1122,  1126,  1142, 
1143,  1146]  the  following  results  have  been  obtained;  ivhich  exhibit,  at 
the  epoch  of  1750,  the  annual  variations  of  the  elements^  during  a  year 
of  3651  days,  namely, 


VI.  vii.§25]  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  217 

dl' 
•2de 


the  annual  sidéral  motion  of  the  perihelion  in  longitude  in  1 750  ;*  [42381 


[4238'] 


=  the  annual  variation  of  the  equation  of  the  centre,  or  that  of  double 
the  excentricity  in  1750  ;t 
-— =  the  annual  variation  of  the  inclination  of  the  orbit  to  the  fixed  ecliptic      r^omn 

d  t  ^  [4239] 


of  1750 


Symbol! . 


— -!^  the  annual  variation   of  the  inclination  of  the  orbit  to  the   apparent     ,.^„^, 
d  t  ^^  [4239] 


ecliptic  ; 

d  è 

-—  =  the  annual  sidéral  motion  of  the  ascending  node  of  the  orbit  upon  the 

d  t 

fixed  ecliptic  of  1750  ; 

de 

— '  :=  the    annual    sidéral   motion  of   the   same    node    upon    the   apparent 
d  t 

ecliptic. Î 


[4240] 


[4241] 


*  (2567)      Neglecting  terms  of  the  order  i^,  we  get     u=^U-\-t.— — ,     by    Taylor's    [4238a] 

theorem  [.38-50a].  The  time  t  is  counted  in  Julian  years  [4078]  and  the  values  of  n,  n',  n' 
kx,.  [4077]  are  taken  to  conform  to  this  unit  of  time,  so  that  n"i,  which  represents  generally 
the  motion  of  the  earth  in  the  time  t,  will  become  simply  n",  in  one  year,  or  when 
t=\.     Now   U  being   the  value  of  m  when  <  =  0,  if  we  subtract  it  from  the  value  for 

dU  [42386] 

the  case  of  ^=1,  which  by  [42.38a]  is   U -\- —,    we  shall    get   the  annual  variation  of 

It  equal  to    —  .       Therefore  if  we  write  successively    «,     2e,     ip,     9,,     è,     6^,    for     u, 

we    shall   obtain    the    annual    variations  of   these  quantities   respectively,  namely,        -— , 

°'      [4238c] 

'^-T,'     Ti'     Ti'      77'       Tr         ^°^  '"  [4080  —  4083]  «  represents  the  longitude   of 

the  perihelion,  e  the  excentricity  of  the  orbit,  9  the  inclination  of  the  orbit,  and  è  the  longitude    moqqji 
of  the  ascending  node  of  m,   upon  the  ^retZ  ecliptic.       Moreover,  9,  is,  as  in  [1143'"],  the 
inclination,  and  ê^  the  longitude  of  the  node  counted  upon  the  apparent  ecliptic.      With  one     ^ .poo 
accent  above  these  quantities,  they  correspond  to  the  body  m';  and  with  iivo  accents  to  the 
body  ni' ,  &«;. 

t  (2568)     Neglecting  terms  of  the  order  e^,  in  the  equation  of  the  centre    [3748],   it 
becomes    2  c .  sin.  {nt-\-  t  —  ra)  ;    the  maximum  value  being  2  e,  whose  annual  variation  is    [4239a] 
^.~  [4238c]. 

X  (2569)     The  formulas  used  for  computing  the  values  [4242  —  4248]  are  as  follows.     [4242a] 
VOL.  in.  65 


218  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

MERCURY. 

^  =  5',627032  +  3',014032  .  (^'+  0',929932 .  (x"+  0%041846  .  f^'" 
at 

+  P,560043 .  f^''+  0',079478  .  i>y+  0S001702. f."'. 
2  .j^  =  0',013690  +  0',  021948  .  |x'+  0',00651 1  .  m-"— 0', 002330  .  t^'" 

—  0',012560  .  i>>'+  0',000116  .  f^^+  0  ,000004  .  t^^ 

Mercury.  ^  ^  ~  0',1 19993  —  0',087951  .  f^'—  0%000052  .  ix"'—  0^028764 .  f^^" 

—  0  ,003215  .  f^"—  0',00001 1 .  /j-". 

[4242]  jf^-^  0''  ^  ^'^^^^  +  0%068409  .  H-'+  0^000508  .  f^"'+  0^098085  .  fx'^ 

+  0%0 10373  .  i>y+  0%000033 .  f^"'. 

—  =  —  4",224994—  P,764590.  m-'— 0',963817  .  p-"— 0',029951  .(x'" 
dt 

—  P,396112  .  M--—  0%068989  .  (x^—  0^001535  .  fx". 

— '  =  —  7%566802  —  0',097574  .  f^  —  4',054426  .  t^'—  0^963817  .  (>■" 
d  t 

—  0',143774  .  fx'"—  2%1 87093  .  i^^''—  0%1 17889  .  m-" 

—  0%002228 .  fi.^'. 

The  values  of  —  ,    —- ,  &ic.  are  given  in  [1126]  ;    2.—,   2.—-,    &c.    are    derived    from 
d  t        (t  t  (t  I  u  t 

[««,     f"'-'^    '-?■   '^■■'^■'•"'    'iï-    s.*"-'™"  [.142,  .143].     L..,y    ^S   f.8.. 
General       ^nd    -r-^ ,    — ^,  &ic.  are  obtained  from  [1 146].     If  we  put  i  for  the  number  of  accents  o«er 

exprès-  "  '         "  ' 

the'annuai     <p;  «)  &•€.  SO  that  (p*'',  -sj^'^  Sic.  represent  the  values  of  (p,  «,  8ic.  corresponding  to  the  planet 
of  the  eie-     vvhicli  is  numbered  i,  according  to  the  notation  adopted  in  [4230]  ;  and  suppose  the  sign  2 

ments  of,,  7.7  •        1    •        i  •  /^ 

the  orbits,     of  finite  integrals  to  include  all  the  values  of  k,  contained  m  the  series  of  numbers,  0,  1,2,  3, 
[4242c]    4,  5,  6  [4230],  excepting  i  =^  ]c  ;  then  the  four  first  of  the  preceding  equations,  may  be  put 
under  the  following  forms,  as  is  evident  by  mere  inspection, 

[4242d]  ^^=i;.J(i,Ar)  — [Tr].^\cos.(:=<'>— «W)5;  [1126] 

[4242e]  2.^  =  — 22.[TF].e^'i.sin.(ra«— b"'1);  [1122] 


_  _2%343127  —  4%315]  77  .  (^  —  5',754638  .  ^."+  1 ',203777  .  t^" 
(It 


VI.  vii.  §25.]  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  219 

VENUS. 

+  6',435827  .  (j."+  0^083814.  (x'+0',003269  .  ,j.''. 

2  .^  =  —  0%260567  —  0',090479  .  fx  — 0%101170.  fx"— 0',006378  .  >'■"' 
a  t 

—  0%061 143 .  <—  O',001409  .  f'+  0',000012  .  m-". 
^  =  —  0%015950  +  0S025200  .  ^  +  0%002I57  .  f^'"—  0%037854 .  (x-   ^^^^^ 

—  0',005455  .  fx''  -I-  0%000002  .  /x"'. 
^'  =  0%044538  +  0',019377  .  f^  —  0',004148  .  fx"'+  0%025810  .  t^-     [4243] 

+  0',003500  .  fx'—  0^000001  .  t^-. 
—  =  _  9,900996  +  0%342053  .  fx  _  7',416280  .  f."—  0%0761 12 .  m-'" 

—  2',66 1705  .  fx-— o%085589  .  K—  0',003363 . ,.''. 
^  =  —  18%387762  +  0',  165450  .  fx  —  5^426693 .  m-'_  7^416280  .  v^' 

—  0',286675  .  fx'"—  5',133067  .  jx"—  0',285519  .  v" 

—  0',004978  .  fx". 


^  =  2.[  a_]  .tang.  ^(«.  sin.  (ôO-ô^'i);  ^242/] 

[1142,1143] 

In  like  manner  the  expressions  [1146]  may  be  reduced  to  the  forms  [4242i,  fc],  supposing 

the  orbits  of  all  the   other  planets  to  be  referred  to  that  which  is  numbered   I  [4230]  ;    ?/''     [4242ft] 

bebg  the  indination,  and  â|''  the  longitude  of  the  node  of  the  orbit  denoted  by  i  referred  to 

that  which  is  denoted  by  I;  conformably  to  the  notation  [1 143'']  ;  the  fixed  plane  being  the 

orbit  of  /,  at  the  epoch  1750, 

-^  =  2.{  (i,Ar)_(/,A')  \  .  tang. <p'*'. sin.  (âio_^(B);  [4242i] 

-^  =  -{l,i)-Mi,^)  +  ^A{i,^-{l,^\-~^yCO,.{è'~^-è^''^).  [42424] 


220  PERTURBATIONS  OF  THE  PLANETS;  [Méc.  Céi. 


THE    EARTH. 


--  =  11*  ,949588  —  0',414923  .  f^  +  3',813276  .  (^'+  r,546163  .  ^^"' 
at 


The  Earth 


4-  6^804392 .  i>^"+  0',  194066 .  1^."+  0',006614 


M-' 


[4244]  2  /-^  =  —  0',1 87638  —  0',008057  .  (^  +  0',030435  .  i^'—  0',049410  .  f/-" 

—  0',  159738  .  i>'"—  0S000909  .  f^''^-  0',000040  .  f.^'. 


Instead  of  excepting  Ic  =  i  [4242c] ,  we  may  suppose  the  sign  2  to  include  all  the  numbers 

[4242Z]     0,  1,2,  3,4,5,6  [4230];  putting   {i,i)=iO,     [TTJ  =  0,  in  all  the  formulas  [4242«i  —  A:]  ; 

observing  also  that  the  first  term  of  [4242Ar],  namely  —  (^j  ^)  is  that  which  arises  from  the 

tano^.  &^''^ 
[4242m]    value  A;  =  i,  under  the  sign  2  ;  because  then        ° — —  =  1;    cos.(é''' — Ô(''>)=:1.  We  may 

moreover  remark,  that  as  the  orbit  of  the  planet  /,  in  1750,  is  taken  for  the  fixed  plane 
[4232/t],  tang.  <p"'  must  be  of  the  order  m,  and  since  this  is  multiplied,  in  [4242/],  by  quanti- 

[4242n]  ties  of  the  same  order,  the  product  will  be  of  the  order  m^,  which  is  neglected  ;  likewise  the 
term  depending  on  tang.  9''' vanishes,  because  it  is  multiplied  by  sin.  {&'■''' — â*'')  =  0.  If 
we   now  substitute  in  [4242f/— t]   the  values   [40S0— 4083,  4231—4237],   we   shall 

[4242o]  obtain  the  expressions  [4242 — 4248]  For  the  sake  of  illustration,  we  shall  give  a  few 
examples  of  the  numerical  calculations  in  the  following  notes. 

*  (2570)    As  an  example  of  the  formula  [4242(/J,  we  shall  compute  the  action  of  Mercury 
on  the  Earth,  in  which  case    i^  2,    A:  =  0,    and  the  corresponding  terms  of  this  formula 
[4244a]     are  (2,0)  —  [Ml  •  -•  cos.  (n"— w).    Substituting  the  values  of  (2,0),  [aiô"],  e,  e",  to,  ra" 
[4233,  4080, 4081],  it  becomes. 


[42446] 


(1  +  p.)  •  ^^  0-,097574  - 0',046285 .  °^^lf^l- cos.  (98^  37"  1 6-73"  33'»  58') ^ 
=  (1  +  fJ^) .  {  0',097574  —  0',512497|=  —  0^414923  —  0^414923  .  ij. ; 

in  which  the  part  depending  on  fx  is  the  same  as  in  — —  [4244],  the  other  part   — 0',414923 

is  included  in  the  constant  term  1 1',949588,  which  is  the  sum  of  all  the  coefficients  of /a,  ja'd, 
14244c]  ....  dzi" 

&ic.  noticing  their  signs.     This  constant  quantity  represents  the  value  of  -r-r-,    supposing    (a, 

/J.',  &.C.  to  vanish,  or  the  numerical  values  of  the  masses  [4061]  to  be  correct. 


VI.vii.<^25.]  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  221 


MARS. 

^"  ^  15',677160  +  0',015944 .  \>.  +  0^511046 .  f.'+  2%129320 .  ^' 

a  t 

+  12%312891  .  (/-"+  0^693878  .  f^^+  0',014082  .  ^''K 
2.  ^"=  0%372537  +  0^002363  .  (x  +  0',001566  .  ,x'-f  0',040492 .  /' 
+  0',314982.,j."+  0',013167  .  p."—  0^000032 .  f^". 
1^  =  —  0',293800  +  0^,000092 .  ^  —  0',013146  .  f^'—  0^254879  .  m-'" 

—  0%025790  .  vy—  0',000076  .  ^^K  *'"" 
1^  =  —  0%012984  —  0',000388  .  (/.  +  0',131893  .  f^'—  0S131999  .  f." 

dt 

—  0',0 12454  .  V-  —  0',000036  .  p".  [4245] 

—  =  —  9%728234  +  0%052224 .  \^  +  0',3 14067  .  (.'—  P,964546 .  ^' 
a  t 

—  7%855103  .  ^i'— 0',266532  .  f^"—  0%008345  .  ,x^'. 

^  =  —  22%789674  —  0',31 8395  .  fx  — 8%577599  .  f.'—  1  ',964546 .  fx" 

—  0^,432999  .  fx'"—  1  P,015955  .  i>'r—  0',469146  .  fx" 

—  0',011033.fx-. 


de" 
In  like  manner  the  terms  of  2  .  —     [4242cj,  depending  on  Mercury,  become  by  using    [4244ti] 

tiie  same  values  as  above, 

—  (1  +  fx)  •  [111]  -26.  sin.  (ra"—  -a) 

=  —  (I  +  (x)  •  0,046285  X  2  X  0,20551320 .  sin.  (98''  3T"  16'-  73'' aS"  58*)  [4244e] 

=  —  (  1  +  ^) .  0',00805T  =  —  OS008057  —  0',008057  .  fx, 

in     which     the     coefficient     of    (x     is   the     same     as     in     [4244],    and    the    quantity 
—  0',00S057     forms  part    of  the    constant  quantity     — 0",  187638    [4244],    as  in    the 

dTS"         r  T  T  •!  rfwCO 

case  of     — —      [4244c].        In    like   manner   we    may   compute   any   other  values    —rrt 

d_f> 
dt  ' 

VOL.  III.  56 


222  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


JUPITER. 


'^—  =  6%599770  +  0',000186  .  f^^  +  0',004330 .  (^'+  0',009837  .  m" 

dt 


Jupiter. 


+  0^002047  .  f^"'+  6%457871  .  (j.''+  0%  125498 .  ix"': 
0%55441 8  —  0',000008  .  m-  +  0',000009  .  f^'+  0',00( 

—  0',000191  .  /x"'+  0',553308  .  f>-''+  0',001220  .  i^", 


*  ^  =  _0, 078140 +  0',000022.(x+0',0001 01  .  |x'+0^000112.f^"' 
at 

—  0',078933  .  M-'  +  O',000557 .  f^". 

^  =  —  0^223178  — 0%009491  .  m.  — 0%128114  .  (^'— 0',010646  .  (x'" 

[4346]  _  0^075444  .  (^^"4-  0%0005 1 6 .  f^^'. 

—  =  6^456281  +  0',000509 .  (^  +  0%005857  .  i^'—  0%009862  .(." 
dt 

—  0%000461  .  f^"'+  6%505571  .  f^"—  0%045332  .  j."'. 

^^  _  14%663377  —  0',316227  .  t>-  —  12S828736  .  i^'—  0^009862  .  t^" 

dt 

—  œ,389153  .  (^"'—  6%947861  .  f^'^+  5%877561  .  t^" 

—  0,049 100  .  H-^'. 


*  (2571)     As   an   example  of  the  use  of  the  formula  [4242/],  we  shall  compute  the 

[4946a]    part  of   — —      depending  on   the  action  of  Mars.       In  this  case     i  ^  4,     A:  =  3,    and 

the  corresponding   terms   of  the    formula   become,  by  using    the    values    [4080  —  4083. 
4231  —  4237]  ; 

(4,3) .  tang.  (?'".  sin.  {&"—  é'") 

[42466]  =  (1  +  1^'")  ■  0',004509  X  tang.  I'' 51™  X  sin.  (97''  54™  22'—  47'' SS"  38') 

=  (1  +|i,"').0',000112  =0',000112  +  0%000112.fA"' 

of  which  the  part  depending  on  ;*'"  is  the  same  as  in     -—     [4246],   and  the  other  term 
0' ,000112  forms  part  of  the  constant  quantity     —  0',078140  of  this  formula. 
[4246c]         In  like  manner  by  putting   i  =  4,     A  =  3,     Z  =  2  in  [4242 J],  and  using  the  same  data, 


VI.  vii.  ^S25.]  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  223 


SATURN 

+  0%000550.f^"'+  15',790810.(x-+0%3]9768.  f.' 


,  =  16%1 12726  +  0',000022 .  t^  +  0',000496  .  fx'+  0S001080  .  i^" 
(It 


2  .  ^  =  —  I ',080409  —  OSOOOOOO  .  f.  +  O',000000 .  f.'+  0^000001  .  /-•" 
a  t 

—  0%000016 .  (^"'—  P,099919  .  fj^"+  0%019524 .  (x-. 

1^  =  0%099740  +  O',000003  .  fx  +  0^00001 8  .  m-'+  0%000014  .  i>!"  ^^^^^^^ 

+  0^,096696  .  H-"  -f  0^003010  .  fx". 
^  =  —  0-,155290  —  0^,010955 .  fx_  o-,1939]  8  .  ^—  0%012542 .  f^'"     [4247] 
+  0%059175  .  fx-+  0',  002950 .  m-". 
*  'jj  =—  9%005292  +  0%000004 .  ,x  +  0',000042  .  ^^—  0%001 123  .  ^' 

—  0',000323 .  (x'"— 8%734249  .  f^-—  0%269642 .  iCK 

^  =  — 19^041499  — 0',1 10961  .  fx  — 5',883249.f^'— 0',001123  .  ^." 
at 

—  0',  141 41 4 .  p.'"—  12',292960  .  t^"—  0',340441  .  (x" 

—  0',271351  .fx". 


we  get  the  part  of    —7^,    or  as  it  is  called    -7^-  [4246],  depending  on  Mars,  equal  to 

\  (4,3)  -  (2,3)  I  .  tang.  9'"  .  sin.  (é-—  é'") 
=  (1  +  fx"').|0' ,004.509  —  0',432999|  X  tang.  1''  51"'  X  sin.  (9T'54"'22'—  47"' 33™  38') 


[4246rf] 


=  _  (1  _f-  ^"') .  0',010643  =  —  0',010643  -  0',010643  .  ix'", 
which  agree  very  nearly  with  the  corresponding  terms  of      -77      [4246]. 

*  (2572)     Putting     i  =  5     in  [4242g-],  we  get  the  expression  of   —,  and  the  terms 

corresponding  to  the  action  of  any  one  of  the  planets,  is  found  by  using  the  value  of  k 
corresponding  to  it  ;  thus  for  Mars  k  =  3,  and  the  terms  depending  on  this  planet 
become,  by  using  the  data  [4080—  4083,  4231  —  4237], 


224  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

URANUS. 
^'  =  2',454851  +  0',000003  .  (^  +  0',000043  .  ^'+  0',000095  .  fx" 

at 

+  0',000048  .  ^^"'+  r,2 10830  .  i>>''+  1 ',243833  .  i^\ 

2  .  —  =  —  0',  1081 84  —  0',000000  .  (^  —  O',000000  .  f^'—  0',000000  .  /x" 
dt 

+  0',000000 .  fj.'"—  OSOl  1952 .  yi"—  0',096232 .  i>y. 

^  =  _  0',048861  +  0',000000 .  i^  +  0',000000 .  f/.'+  0%000000 .  f^'" 

""""'•  —  0',009036.(x-— 0^039826.,x^ 

4^'-  =  —  0',027460  —  0',005492.pi  +  ^,010145./—  0',005907 .  f^^'" 
a  t 

[4248]  +  0',05921 7 .  9^"  —  0%030502  .  i>.\ 

—  =  2^,700876 +0',00001 7.  f^+0S000146.fx'—0',000096.(^" 
dt 

+  0',000047 .  M-"'+  0',496382 .  i>:"-\-  2^204381  .  i>.\ 

l!il'  =  _  34\403396  —  0',78851 7 .  \>-  —  23^81 5885 .  i>!—  0^000096 .  f^" 
dt 

—  0',938767  .M-'"— 10',200902  .  ,x-+  1 ',347 866.  j^" 

—  0',007096.fi.". 


■(5'3)+(5'3)-tïï!|^---(^'-^"') 


=  (I  +  fx."').  5  — 0-,000479  +  0'.000479/^"^' ^,„^^'"°'.cos.(lll''30"'23'-47''3S'"38^)  ] 
\      ^    '^   '    I  '  '       -  tang.  2'^  29™  55'  ^  '  ) 

[4247i] 

=  (1  +  fJ^'") .{  — 0',000479  +  0^000156  } 

=  _0',000323  — 0^000323.fA"',      as  in     ^[4247]. 

d  é^      • 
Putting     1  =  5,     Z  =  2,  in  [4242^],  we  obtain  the  expression  of  — j-,  in  the  notation 

[4247c]     °f  [4247].     The  term  of  this  expression  corresponding  to  Mars,  is  found  by  putting  k=3, 
and  using  tlie  above  data,  by  which  means  it  becomes, 


VI.  vil.  § ^'5.]  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  226 

The  variations  of  the  earth's  orbit  are  not  included  in  the  preceding  formulas  ; 
they  may  be  determined  by  the  equations  * 

tang.  <?".  sin.  f  =  p"  ;  tang.  /.  cos.  o"  =  q".  [4349] 

With  resjiect  to  the   values  of    p",     q",    we  may  determine  them  by  the 
formulas  [1132,  &:c.],  and   we  have,  by  taking  the  ecliptic  of  \1 50  for  the     [4249] 
fixed  plane,i 

d  p" 
in  which     t     is  the  number  of  Julian  years  elapsed  since  1750,  and     -rr^ 


[4250] 


r/q"      rldp' 


,  ,    &.C.  are  taken  to  correspond  to  that  epoch.      It  is  only  necessary 

to  notice  the  first  power  of  t  in  these  formulas,  if  t  be  less  than  300. 
If  t  do  not  exceed  1000  or  1200,  we  may  reject  the  third  and  higher  powers 
of  t  ;  and  we  may  do  the  same   even  with  the  most  ancient  observations, 


[4250'] 


[4250"] 


-  (5,3)+  <(5,3)-(2,3)}.^^'.cos.(év_r) 

=  (!-]_  |j,"').  )  _  0^000479  +  (0',000179  —  0',432999).      ^'.^^    ^■.  cos.  63-' 51"  45'^     [4247rfJ 
\      ^    '^   '     I  IV.  I  /  tang.  S"*  29"' 55»  3 

=  (1 +fj-"').{— 0',000179  — 0',141035|  =  — 0,141514  — 0%141514.(a"', 

which  differs  0',0001   from  that  given  by  the  author.       We  have  thus  given  an  example  of 
the  numerical  calculations  of  each  of  the  formulas  [4212(/  —  k'\. 

*  (2573)     The  formulas  [4249]  are  similar  to  [1032],  accenting  p,    q,  Sic.  with  tioo    r4249„] 
accents,  in  order  to  conform  to  the  case  now  under  consideration. 

t  (2574)     Putting  successively    m  =p";      U  =  p"  ;    or     u  =  5",     TJ  =  q",     in    the 
formula  [3850«],  we  get  the  following  expressions  of  p" ,  q", 

in  which  the  quantities    p",     q",    and  their  differentials,  in  the  second  members,  correspond 

to  the  epoch  of  1750.     Now  at  that  epoch  we  have    9"  =  0  [4249']  ;  substituting  this  in    [42506] 

[4249],  we  get    p"=  0,     q"=  0  ;     hence  the  formulas  [4250a]  become  as  in  [4250]. 

VOL.  III.  57 


226  PERTURBATIONS  OF  THE  PLANETS;  [Méc.  Cél. 

taking  into  view  their  imperfections.      We  obtain  from  the  formulas  [4250], 
Value.        the  following  results.* 

CO r re 3- 
po.ndiag 

rrrlil  '^  =  0%076721  +  0',008420 .  m-  +  0%0863 16.^'+  0%009423 .  ,a"' 

odiit.  a  t 


[4251] 


—  0»,022021  .M.'"—  0^005446  .  i^--+  0s000029.|x^'. 

^  =  —  0%500955  —  0%008522./x  —  0',309951 .,/-  0%010335.f/^" 

—  0',1 58234. /x'"—  0',013821  .F-^—  0%000091  .f^^'. 


theperi"  26.     Wc  havB  seen,  in  [4037],  that  the  oblateness  of  the  sun  produces,  in 

helion  de- 

the"t'n,p°"  the  perihelia  of  the  planetary  orbits,  a  small  motion,  which  is  represented  by, 

cily  of  the 

sun.  y-j2 

[4252]  5«=.(p_X^).-:.„^. 


*  (2575)      If  we    substitute    tlie    values  p",    q"  [4250J,  in  the  terms  of     -j-,        — 

d  p" 
[1132],  depending  upon  p",  or  ç",  they  produce  terms  of  the  order  {(2,0)  +(2,l)+&ic.  }•  —  ; 

[4251a]  .   ,         ,  .  .  .,      dp"      dq"       ,.  ,  •      ,     c  u         <•  u 

or  01  the  order  m  m  comparison  with    — ,     — ,  which  occur  in  the  first  members  ol  these 
^  dt'      dt' 

equations  ;  therefore   these   terms   may   be  neglected,  and  then  the  values  of    — — ,       — • 

[1132],  become, 

Ji"  =  (2,0)  .  q  +  (2,1).  2'  +  (2,3)  .  q"'+  &c.  ; 

[42516]  .  „ 

^  ^  _  (2,0) .  p  -  (2,1) ./-  (2,3)  .p"'~  he. 

[4251c]     Substituting  p  =  tang. cp. sin. é,     p'  =tang.  9'.  sin.ô',  &,c.;     q  ^tang.  q>  .cos.^,  &;c.  we  get 

[4251rf]  ''■JT  ^  (2.0)  •  tang.  <p .  cos.  ^  +  (2,1  ) .  tang.  9'.  cos.  6'  +  (2,3) .  tang.  9'".  cos.  ()'"+  Sic.  ; 

[4251e]  rfl"  ="~  (^'^^  •  tang.9-sin.â  —  (2,1) .  tang.9'.  sin.  â'— (2,3)  .tang.  9'".  sin.ô'"—  he  ; 

and  by  using  the  values  [4082,  4083,  4233],  they  become  as  in  [4251]  nearly.     Thus  the 

(l  p" 

term    of      —- ,     depending  on  Mars,  is 

[4251/]        (2,3). tang. 9'". cos. r=  (1  +  |x"') .0',4.32999 X  tang.  l-'Sl™ X  cos.47''38'" 38' 

=  (l+H."')-0''009423, 


Vl.vii.§26.J  SECULAR  VARIATIONS  OF  THE  ELEMENTS.  227 

We  shall  consider  the  motion  relatively  to  Mercury.     Now    q    is  the  ratio  of     [43531 

the  centrifugal  force  to  gravity  at  the  solar  equator  [4028]  ;   and  if    mt     be 

the  sun's  angular  rotary  motion,  the  centrifugal  force  at  the  solar  equator  will     ^oss'i 

bo  ni'D*     Puttine;  the  mass  of  the  sun  enual  to  S,  we  havef     -^,.l=^»"^  or     ,,„,„ 
*  1  a^  [4254] 

.S  =  ti"-.  a"',     which  gives  the  gravity  at  the  solar  equator, 

S         n"2.a"3 


2)3  DP     ' 

therefore  we  have  % 


m'       D^  /ot\2    /D\3 


[4255] 


The  time  of  the  sun's  revolution  about  its  axis,  according  to  observations,  is 
nearly  equal  to  25'*°y%417.     The  duration  of  the  earth's  sidéral  revolution  is      [4257] 
365'""^S256  ;  hence  we  obtain, 

TO        365,256 


n"         25,417 


The  apparent  semidiameter  of  the   sun,  at  its  mean  distance,  is  96P,632; 


which  gives 


[4258] 
[4259] 


dp" 

in  which  the  coefficient  of  iu-"'  is  the  same  as  in  the  value  of    — -    [4251].     In  like  manner 

at 

dp"      dq" 

we  find  the  Other  terms  of   ——,    — —   [42511. 

dt       dt    ^         ■■ 

*  (2576)     The  angular  rotary  velocity  being  to,  and  the  equatorial  radius  D  ;  the  actual 
velocity  of  a  point  of  the  surface  of  the  equator  will  be  represented  by    to  D.      The  square    [4253o] 
of  this,  divided  by   the   radius  D,  gives  the  centrifugal   force    [54'],   equal  to  m^D,    as 
in  [4253]. 

t  (2577)     We  have   n^  =  ^3  =  "^^^  [3700, .3709a]  ;  and  in  like  manner  n"'^=^^ .    ^^254a] 
Now  changing  M  into  S  to  conform  to  the  notation  [4254],  neglecting  also  to" in  comparison 

Ç  /t"3 

with  S,  we  obtain     -^  =  n"^  [4254];  multiplying  by  —  we  get  [4255].  [42546] 

jt"2.a"3      . 
t  (2578)     The  centrifugal  force  ni'D  [4253'],  divided  by  the  gravity      -p— ,  gives  q 

[4253],  as  in  [4256]  ;  substituting  the  values  [4258,  4260]  it  becomes  r4255o] 

q  =  (^54^^)^.  (sin. 961',632)='  =  0,000020926,  as  in  [4261]. 


228  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

[4260]  ^  =  sin.  961%632; 

a 

therefore  we  have 

[4261]  y  ==  0,0000209268. 

If  the  sun  be  homogeneous,  we  have  p  =  l;q  [1590',  1592'],  m  which  case 
the  motion  of  Mercury's  perihelion  [4252],  produced  by  the  ellipticity  of 
the  sun,  is* 

or  the  equivalent  expression, 

[4264]  <5  «  =  ^7 .  (sin.  961 ',632)-.  T- Y.  nt. 


[4262] 


If  we   substitute  in   this  formula  the  values  of   n,     «,     a"  [4077,  4079],  it 

[4265]      becomes  f>-r^  =  0  ,012250.^  ;  so  that  it  increases    '-^  [4242]  by  the  quantity 

0',012250,  which  is  nearly  insensible.  This  must  be  still  farther  decreased 
if  the  sun  be  formed  of  strata  whose  densities  increase  from  the  surface  to  the 
centre,  as  there  is  reason  to  believe  is  the  case.f  Hence  we  may  neglect  this 
[4266]  expression  for  Mercury,  and  much  more  so  for  the  other  planets.  The 
variations  of  the  nodes  and  inclinations  of  the  orbits,  depending  on  the 
same  cause,  may  also  be  rejected  on  account  of  their  smallness  [4045'] 


*  (2579)     The   density  of  the  sun  being  supposed  uniform,  we  have   'h?  =:  ^q  nearly 
[4262a]     [1590'].     Moreover  by    [1592']    the  polar  semiaxis   being    1,  the  equatorial  semiaxis  is 
\/{\  -f-  'i^)  =  1  +  J^^  =^  1  4~  i*/  nearly  ;  so  that  the  ellipticity  p  is  nearly  equal  to  fç,  as 
in  [4262]  ;  substituting  this  in  [4252J  we  get  [4263].     Now  we  have 

[42621]  V^-7,-  5  =  ( -"•  961',632)^  g)'  [4260]  ; 

hence    [4263J   becomes    as   in   [4264]  ;     and  by   using  the  values   of     q,      a,      a",      n 
[4261,  4079,  4077],  it  becomes  as  in  [4265],  namely, 
[4262c]     5^^  I  X  (0,0000209268) X (sin. 961',632f  X  (0,.38709812)-2  X  538101 6^ <  =  0',01 250. <. 

t  (2580)  The  effect  of  increasing  the  density  towards  the  centre  is  seen,  in  the  extreme 
r4266a]  case,  when  the  whole  mass  is  collected  in  the  centre,  and  p  =  io-tp  [1732'"];  or  in 
the  present  notation  f^hq  [1726',  4253].  Substituting  this  in  [4252],  we  get  ira=Oj 
so  that  in  this  case  the  ellipticity  has  no  effect  on  the  motion  of  the  perihelion  ;  hence  it 
[42665]  appears  that  this  increase  of  density,  towards  the  centre,  decreases  the  motion  of  the 
perihelion.  We  have  supposed,  in  this  example,  that  I)  remains  unaltered,  the  density 
being  considered  as  infinitely  rare,  from  the  suiface  towards  the  centre. 


VI.  viii.  V-î"?-] 


THEORY  OF  MERCURY. 


229 


CHAPTER   VIII. 


THEORY  OF  MERCURY. 


27.  The  inequalities  of  the  planets  which  are  independent  of  the 
excentricities,  and  those  which  depend  on  the  first  power  of  the 
excentricities,  were  computed  by  means  of  the  formulas  [1020,  1021,  1030], 
having  previously  ascertained  the  values  of  ^"'*,  ^^''  &c.  and  their 
differences,  by  the  formulas  [963'^  —  1008].  The  results  of  these 
calculations  are  contained  in  this,  and  in  the  following  chapters,  neglecting 
the  perturbations  of  the  radius  vector,  whose  effect  on  the  geocentric 
longitude  of  the  planet  is  less  than  one  centesimal  second.     To  determine  * 


[4267] 


TertiiB 
whieh 
may  be 
neglected 
on  account 
of  their 
ainallnc". 


•  (2581)  Let  S  be  the  sun,  E  the  earth,  M  Mercury,  supposing  it  to  move  in 
the  plane  of  the  ecliptic  ;  S  T  the  line  drawn  from  the  sun  towards  the  first  point  of  Aries  in 
the  heavens,  being  the  hne  from  which  the  longitude    v,    v"  are  counted.     Then  S  E  =t" 


F 


74 


(4Q(Jf''al 


Hence  the  longitude  of  the  sun,  as  it  appears  from 

the    earth,    is     180''-[-f";    and   if  from    this    we 

subtract    the    angle  of  elongation     SEM  =^  E, 

we  shall  obtain  the  geocentric  longitude  of  Mercury 

V=lSO''+i'"— £.       Now    if      SM=r     be 

increased  by  the  quantity  MJ\1!  =  or,    the  angle 

E    will  increase  by  the  quantity    MEM'z^SE,'^' 

while    V,    v"  remain  unaltered  ;    therefore  the  variation  of  the  preceding  value  of    V    will 

be    5V^  —  f5£.     If  we  draw  .M'.Y,    EF,    perpendicular  to    EM,    .S./V/ respectively, 

w-e  shall  have  in  the -similar  triangles     J\1JYM',    MFE;      ME  :  EF  ::  MM  :  M'N;    [4268rf] 
EF 

ME' 

(5  E  =  —  5  V  : 


[42(3S6] 


[4268c] 


hence      iV/'JV=dr. 


angle 


MEM' 


Dividing  this  by    M' E,  or  ME,    we  obtain  very  nearly  the 
EF 


or 


substituting      EF  =  S  E.sm.ESM 


ME'i' 

=r".sm.{v—v"),  and  ME^=r"^—2r"r  .cos.{v—v")-}-t^=r''^.\l—2<x.cos.{v  —  v")■j-oJ 
[6■2  Int.  4268],  we  get  [1269]. 
VOL.  III.  68 


[4'i(>er] 


230  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

the  limit,  which  an  inequality  in   the  radius  vector  must  attain,  to  produce 
one  second  in  the  geocentric  longitude  of  Mercury,  we  shall  observe  that  if 
[4a68]     we  put  this  longitude  equal  to     V,    and     r  =  ?"a-,    we  shall  have   for  the 
variation     ôV     corresponding  to     Sr, 

,.  Sr  sin  (v — v") 


[4270] 


The  maximum  of  the  function 

s'in.(«  —  v'') 


1  — 2a.cos.(j;— i;")-l-a'' 


corresponds  to^ 


[4271]  cos.(z^-t?)  =j-p- ;J 

[4271']     which  gives     ^     [4270e]      for    this    maximum  ;      therefore    we    shall 

then    have,t 


*  (25S2)     The  maximum  of  [4270]  is  found,  by  taking  the  differential,  supposing   v    to 

270       b^  t'l^   variable    quantity;    putting  it  equal   to  zero,  and  dividing  by    d.{v  —  v").      This 

differential  expression  being  multiplied  by    |1 — 2a. cos. (y  —  ii")-|-a-p  becomes,  without 

[4270i]    reduction,  as   in  the  first  of  the    following    expressions,    and    this  is  easily  reduced  to  the 

last  form  [4270(/]  ; 

[4970c]  0  =  cos.(«—  v")  .  \  1  —  2o..cos.(« — v")-\-a?l  —  2a.  sin.^.  (t)  — v") 

=  (1  +o.^).cos.{v  —  v")—2a..{cos.^.{v—v")  +  sm.^.{v  —  v")] 
[4370dJ  =  (1  +a2).cos.(i'— î>")  — 2  a. 

From  this  we  easily  obtain  [4271]  ;  thence 

.  /  4a2    U_l-a2 

[4270e]  V  {l  +  c>-2)V  l+a2 

l-2a.cos.(.-.")  +a2=  1  -  .^-p^,  +  a===  \-:^^ . 

Dividing  the  first  of  these  expressions  by  the  second,  we  get  the  value  of  the  maximum  of 
the  function  [4270],  as  in  [4271']. 

t  (2583)      Substituting  in   [4269]   the  value  of  the  function   [4270],  at  its  maximum 
t4271a]  6r  1 

[4271'],    we  find     &V  = ;  .  :; :,;    hence  we  get    or  [4272]. 


n.  viii.^27.] 


THEORY  OF  MERCURY. 


231 


<S,-  __,•".(!  —a'^).. 5  V.  [4272] 

If  we  suppose    iV  =  ±  1"=  ±  0,324,    and   take   for    r,     r",    the  mean 
distances  of  Mercury  and  the  earth  from  the  sun  [4079],  we  shall  have  by      ^^^^^^ 
\vliat  precedes     r"  =  1  ;     a  =  0,38709812  [4095]  ;     hence  we  obtain* 

6r=^  0,000001335  ;  [4274] 

therefore  ive  may  neglect  all  the  inequalities  of  the  radius  vector  of  Mercury, 

in  which  the  coefjicient  is  less  than,  rt  0,000001.      Among  the  inequalities  of  [4275] 

the  motion  in  longitude,  we  shall  retain  generally  only  those  whose  coefficients  i„equaii- 

e\ceed  a  quarter  of  a  centesimal    second    [0,081];    but  as  the   inequalities  ^^^^J^» 

depending  on  the  simple  angular  distances  of  the  planets  can  be  introduced  ^«JTbe 
into  the  same  table  with  those  of  greater  magnitude,  they  are  retained. 


Inequalities  of  Mercury,  independent  of  the  excentriciiies. 


iv  =  (1+0 


+  (l+0- 


0%662353  .  sin.  (n't  —  nt  +  e—  s)  \ 

—  r,457111  .  %\n.2{n't  —  nt  +  ^'  —  ^)  j 

—  0',  128075  .  s\n.3(n't  —  n  <  +  s'  —  0  ' 

—  0',029264 .  sin.4(n'«  —  nt  +  s—^) 

—  0%008905 .  sin.5(n'«  —  nt  +  i  —() 

0',201 688  .  sin.  (n"t  —  nt  +  ^"-  s) 

—  0',  165645  .  sm.2(n"t  —  n  i  +  «"  — 0 

—  0',016901  .  sin.3(n"«  -  nt  +  s"-  0 

—  O',003127  .  sm A(n"t  -  ni  +  s"-  0 


[4276] 


Inequali- 
ties inde- 
pendent of 
the  ec- 
centrici- 
ties. 


0',569336  .  sin.  {n'H  —  nt  +  i"-  0 

_|-  (1  4- ^iv) .  I  _  0-,l  1 8384  .  sin.2(n'H  —  nt  +  ^'—  0 

—  O',003 118.  sin.3(M''i  —  nt  +  s'^—  0 


*  (2584)  Using  the  mean  values  r  =  a,  r"  =  a"  [4079],  we  get  a  [4095], 
substituting  these  and  6V  =  ±  1",  or  o  V  =  dz  sin.  1"  =  ±  0,324 .  sin.  1%  we 
obtEÙn    [4274] 


[4274o] 


232  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  C^l. 

/       0,0000000376*  \ 

\  —  0,0000004094 .  cos.  (n't-nt  +  i'-s)   1 

[4277]  i  r  =  —  (1  +  /) .     +  0,0000015545  .  cos.2(n't  —  n  i  +  e'  —  i) 

+  0,0000001702  .  cos.3(n't  —  7i  i  +  s'  —  s) 
+  0,0000000437  .  cos.4(n' t  —  7it  +  i—s) 


*  (2585)     The  parts  of    or,     5v  [1023,1024]    independent  of  the  excentricities  are, 
by  using  T  [.3702a], 

[4277a]  ^.  =  _^  .  a3.(^_  j+  _  .  V.  I -^^,,^,,^_^ ^■cos.^  i'; 

[42774]  5  u  =  —  .  2  .  )  :- .  a  ^"  -\ r-. ,.    ,  ' -5 -r, (  •  sin.  i  1  ; 


[4277rf] 


[4277c]  in  which  m,  «,  w,  s  correspond  to  the  disturbed  planet,  and  m',  a  n',  s',  to  the 
disturbing  planet.  These  expressions  must  be  accented  so  as  to  conform  to  the  notation 
[4061,  4077 —  4083],  taking  for  i  all  integral  numbers  from  i=  —  œ  to  z'^co.  For 
example,  if  we  wish  to  calculate  the  action  of  Mars  on  the  earth,  we  must,  in  the  formulas 
[4277«,  &],    change     m,     a,     n,    s       into      vi",    a",    n",    s",    &c.   corresponding   to    the 

[4277  e]  disturbed  planet;  and  m',  a',  n',  s'.  &c.  into  ?;/",  «'",  n'",  b",  kc.  respectively, 
for  the  disturbing  planet. 

As  an  example  of  the  use  of  these  formulas  we  shall  apply  them  to  the  computation   of 
the  perturbations  of  Mercury  by  the  action  of  Venus.      The  constant  part  of    5r  deduced 

r4Q77/'l 

from  the  first  term  of  [4277a]  is  as  in  the  first  expression  [4277ri].      This   is  successively 
reduced,  by  the  substitution  of  the  values 

•0) 

fdA^o)^  1       dbi     ^g^^g^^  „  =  0,.38709812     [4079], 


da    )  (i''2      do- 

(0) 

[4277g-]        -=  a  =  0,53516076     [4085],         -^  =  0,780206  [4088],     ?«'==  ii^  [4061]: 
a'  d  CL  oboloU 

III) 
m'      „    /'dA('>)\                m'  a"       db^ 

ùr  =^  -—.cr.     -~ —  1  = ■  a. 


G        '  \  da   J  6  a'2      da. 

[4277/t]  ^  (0, 

=  -  -  .  a  a2.  — :  =  —  (1  +,a')  .  0,0000000.370,    as  in    [4277]. 

Again  by  putting  successively    i=!,    i=— 1,     .^'i'=^(-"    [954"J,    in    [4277o], 
and  connecting  the  two  terms,  we  obtain  the  part  of  &r  depending  on  cos.  T,  namely. 


VI.  viii.§27.]  THEORY  OF  MERCURY.  233 

Iiicqual'.ties  depending  on  the  first  power  of  the  excentricities.* 

0-,295201.sin.(H.'^  +  .-'_^) 

-4-,030852.sm.(2?i'«—     nt  +  2-:'—    £  — ^) 

-  ]%686n4>.s\n.{3nt~2nt  +  3e'  —  2s  —  z^) 

6-i,  =  (1  +  ,/)  .  ^  +  0'/J93989 .  sin.  (3  n't  —  2nt  +  3s—2  s  —  ^')  )  [4278] 

+  (»%'293992.  sin.(4  n't  —  3  n  <  +  4  .'  —  3  £  —  ^) 

—  0%17682;).sin.(2M/;_    nf  +  2e—    i' —  ^) 

+  0%394 1?,6 . sin. (3 n  t—2n't  +  3  s  —2e' —  ^) 

Ô  r  =  m'  n^a.)  ^  '^  "  ^     ,  "~" (  .  cos.  T  ;  [4277i] 


[42774] 


in    which    we     must     substitute  a.^"'==a^ — a.OA,     o-'.  ( ==  a^ — a'^.  

\  da    J  do. 

[997,1000,963''],  and  use  tlie  values  [4277f]  coriesponding  to  the  disturbing  and  disturbed 

planets.      Tiius    in   computing    tiie    action    of    Venus  upon    Mercury,  we  must   use    the 

values      o,  a,  m'[4-277o-],    ji  =  538101 6',736,     ?i'-^  210664 1',520  [4077],    ^i,   [4087], 

(1) 

j^    [4088],       and    we  shall   get        (5  r  =  0,0000004094  .  cos.  T,       as    in   the    second 

line  of  [4277].       The  terms  depending  on    cos.  2  T,     cos.  3  T,     cos.4  T,  &c.    are  found 

from  [4277n],  by  using  successively,     i  =  =p2,     i==\^3.     i  =  ^4,    &c.  [4277to1 

In  like  manner,  the  part  of  '5 v  [42776],  depending  on  sin.  T,  is  found  by  using  i  =  ^l  ; 
hence  we  have 


<  \  da    /    '    n — n  > 


^'^-n^'.l  j£^,^,  .  aA'-r^    -f    -     t^^^,;;]:^,;  _  J}.~;^  ^  •  sin.  T.  ^^^..^^ 

Substituting  the  values  of  the  elements  given  in  [4277^,/],  it  becomes     0^6623.  sin.  T,      as 

in  the  first  line  of  [4276]  ;  the  other  terms  depending  on    sin.  2  T,    sin.  3  T,  he.  are  found    [4277o] 

in  like  manner,  from  [4277/./],   by  using  successively     «  =  zt  2,     «  =  ±3)  he.       The 

similar  terms,  corresponding  to   the   other  planets,  are  com[)uted  by   means  of  the   same 

formulas  [4277a,  6],  altering  the  accents  as  in  [4277t].     The  results  of  these  calculations 

are  given  in  [4289,  4290  ;  4305,4306  ;  4.373,  4374;  4388,  4389;  4463,4464;  4523,4524].    ^^^'^'^^ 

*  (2586)     The  terms  depending  on  the  first  power  of  the  excentricities  are  those  parts  of 
ir,    ÔV,  [1020.  1021],    containing  e  and  e.      The  calculation  of  these  terms  is  made  as    [4278a] 
in  the  preceding  note  ;  using  for  e  the  excentricity  [4C80],  corresponding  to  the  disturbed 

VOL.  III.  59 


234 


PERTURBATIONS  OF  THE  PLANETS; 


[Mée.  Cél- 


Inequali- 
ties de- 
pending 
on  tbetirst 
power  of 
the  excen- 
tricities. 


[4279] 


0',09541 8 .  sin.(n"i  +  e"— ^) 
+  (1 +f^")-<|  —  0',461708.sin.(2n"i_    wi  +  2s"_    £_™) 
+  0 ,244148.8111.(3  n"t  —  2nt  +  3/'—  2  e  —  ™) 


0',236346.  sin.(n'''i  +  s"  _  ra) 
+  (1  +  f^'^)  .  {  —  (r,572172.  s\n.(7i'H  +  ^'^  —  ^'0 

-  3 ,278687  .  sin. (2  n'H  _  n  <  +  2 1"  —  e 


(1+^^). 


O',084]67  .  sm.{n'i  +  s" —z^") 
+  0',395493  .  sin.(2n"ï  —  rU  +2  5" 


-.) 


') 


3r  =  —  (1  +p.').0,0000013482.cos.(3n'i  — 2n^+3£'  — 26— z;j) 
—  (1  + 1^").  0,0000029625  .  cos.(2 n"i—    nt+2  s'"—    s  —  ^). 

Inequalities  depending  on  the  scjuares  and  products  of  the  excentricities  and 

inclinations  of  the  orbits. 


[4280] 


[4281] 


These  inequalities  have  been  calculated  by  the  formulas  of  [3711 — 3755]. 
Now  twice  the  motion  of  Mercury  differs  but  very  little  from  five  times  that 
of  Venus  ;*  so  that  5(n'  —  n)  +  2n  is  very  nearly  equal  to  — n;  we  must 
therefore,  as  in  [3732],  notice  the  inequality  depending  on  3nt — 5  n't. 
The  angle  37i't — 7it  varies  quite  slowly,  therefore  it  is  necessary  to  notice 
the  inequality  depending  on  it  [3733].  Moreover  the  motion  of  Mercury  is 
very  nearly  equal  to  four  times  that  of  the  earth,  so  that  4.(n" — n)  +  2w 
differs  but  little  from  — n;  therefore,  we  must,  as  in  [3732],  notice  the 
inequality  depending  on    2nt  —  4<n"t.     Hence  we  obtain, 


[4282a] 


planet;  and  for  e    the  value  [4080]  corresponding  to  the  disturbing  planet;  these  symbols 
being  accented  so  as  to  conform  to  these  two  bodies. 


*  (2587)     Using   the   values   [4076^]    we  have  very  nearly     2  n 


.5n'=z  72°  = 


23" 


3n'  —  n=:289'^  =  ^,    and    71 — 4  ?j"  =  61°  =  —  ;    so  that  these  three  quantities    are 

small  in  comparison  with  71,  as  is  observed  above.      Hence    5  («'  —  n)  -j-  2»t    is  very  nearly 

r4282tl    equal  to   —  «,    and  must  be   noticed  as  in  [3732]  ;    also   3  (ji'  —  74)  -(-  2  n   is  very  small, 

and  must  be  noticed  as  in  [3733]  ;   lastly   4  (?i" — n) -j- 2  n    is  very  nearly  equal  to    — n, 

and  must  be  noticed  as  in  [3732].    The  ;enns  ofiî[3745-3745"'jdependingon these  angles 


VI.viii.§27.]  THEORY  OF  MERCURY.  235 

^       l',690443.sin.(3n<  — 5»'<+3î— 5e'— 43^18'"32')) 

i  r  =  _  (  1  +  f^  ).  s       o-,597664  .  sin. (3  n  t—    n  /  +  3 /—    £  +  4O"36™350  (    M^'Sl 

V  ■'         second 

—  (  1  +  f.")  .    0',263474  .  sin.  (2  n  /  —  4  n'7  +  2  s  —  4  s"—  41 M  1  ""  46^ 
ir  =  (1  -f  ,j.').0,0000016056.cos.(3n^  — 5n'i  +  3£  — 5e'  — 42^58"'04'). 


the 
order. 

[4282] 


are  found  by  pulling  in  the  first  case    ?'^  5  ;    in  tlie  second  i^3,   and  in  the  third  i  =  4. 

The  values  of  ^W"',    iW'",    M^'^^,    .'V/'^',  corresponding  to  these  values  of  i,  are  successively    [4282c] 

obtained   from     [3750,   3755,  3755',  3750'"]  ;     and  they  may  be  reduced  to    terms    of 

U'\  - — ,  &:c.  by  means  of  the  formulas  [996  — 1001].  These  values  are  to  be 
substituted  separately  for  Jfcf  in  the  expressions  of   -^,     àv,    [3711,3715],    and  we  shall    [4282d] 

obtain  very  nearly  the  terras  of      —  ,      5  r,       having    the     small     divisors      5  n'  —  2  n, 

3  n'  —  n,     4  n' —  n,    which  are  the  only  ones  necessary  to  be  noticed  in  this  place.       Now    [4282e] 

if  we   use,   for  a  moment,   the  abridged  symbol,     T.^iJn't — n  t  4- ^ — e)-\-2nt4-2e 

i^  [4282/] 

[371  lij-],  the  resulting  terms  of     —      or      5r    [3711,  &ic.]  will  be   of  the  form   [4282/t]. 

Developing  this  by  [24],  Int.  it  becomes  as  in  [4282?];  substituting  .^jsin.  Z?,  for  the 
coefficient  of  sin.  7',  also  ,/2,cos. -Bj,  for  the  coefficient  of  cos.  T^,  it  changes  into 
[4282t],  and  is  finally  reduced  to  the  form  [4282/],  by  means  of  [24],  Int.  [428%] 

dr  =  J»f/<".cos.(T— 2;n)+J/;".cos(T— a— ^')+M/2\cos.(r— 2îi')  +  i>7/3>.cos.(T— 2n)  [4232^] 
=  { M}^'.  cos.  2 Î3  +  AJ^'K  cos. (îi  +  -/)  +  Jl/'^'.  cos.  25/  +  M/". cos.  2 n  | .  cos. T, 

+  { ./U;»'.  sin.  2  w  +  .W  ">.  sin.(i^  +  z,')  +  iVif  \  sin.  2  ^'  +  M,'^\  sin.  2  n| .  sin.  T,  ^*^^^'^ 

=  ^1.5 cos.  S, .  COS.  T,  +  sin.  5,  .  sin.  1] }  [42824] 

=  A,  .  cos.{T-B,),   as  in   [4282].  [4282^] 

In  like  manner  the  several  terms  of    i5  v    may  be  reduced  to  the  form    A-3.  sin.(T, —  B.-,)  ; 

there  is  no  other  difficulty  than  the  tediousness  of  the  numerical  calculation,  arising  from  its     [4282m] 

length. 

We    may  observe   that    the    quantities    7^,    2  IT,    which  occur    in    [3745'"],    are    not 
explicitly  included  among  the  data  [4077  —  4083],  but  must  be  computed  from  the  formulas    [4282n] 
[10.32,  103.3]. 

7  .sin.n  =z  tang. 9'. sin.  â' —  tang.  9. sin. é;     7. cos.  n  =  tang. 9'. cos.  â'—  tang.  9. cos.  Ô;         [4282o] 

supposing  9,  é  to  correspond  to  the  disturhed  planet,  and  9',  è'  to  the  cUsiurbing  jilanet  ; 
these  symbols  being  accented  so  as  to  conform  to  the  notation  [4230]  ;  then  using  the 
values  [4082,  4083]  we  get  the  required  values  of  7,  n. 


236  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Ct 


Inequalities  depending  on  the  cubes  and  jirodncts  of  th-ee  dimensions  of 
the  excentricities  and  inclinations  of  the  orbits. 

The  first  of  these  inequalities,  depending  on  the  angle    2nt  —  5  n't,    is 

[4282']     computed    by  means    of   the  formula  [3844]  ;*    the   second,  depending  on 

the  angle    nt  —  4 /<%     is  found  by  means  of  [3882]  ;t  hence  we  obtain, 

ÔV  =  —{l  +f^')-8',483765.sin.(2ni  — 5w'^  +  2s— 5.='+30''13'"36') 
ineq^.ii.  —  (1  +  O  •  0',690612  .  sin.(    n  i  — 4  n"t  +    £  —  4="+ 19^02'"  13'). 

ties  of  Ihe 

etder.  The  inequalities  of  Mercury's  motion  in  latitude,  may  be  calculated  by- 
means  of  the  formula  [1030]  ;  but  as  they  are  insensible,  being  less  than 

[4283]  ^  quarter  of  a  centesimal  second,  it  was  thought  unnecessary  to  insert 
them. 


r4283ol         *  (2538)     The  first  line  of  [4283]  is  obtained  from  the  formula  [3844],  connecting  all 
the  terms  into  one,  as  in  \_4282h —  ?]. 


[42836] 


t  (2589)  The  second  line  of  [4283]  is  obtained  from  [3882],  reducing  all  the  terms 
into  one,  as  in  [4282/i  — Z].  We  have  already  seen  in  [3883/(],  that  the  correction,  as  it  is 
given  by  the  author,  in  [4283],  is  rather  too  great  ;  his  method  of  computation  [3882]  being 

i  J     merely  an  approximation.      The  direct  method  of  computation  has  already  been  explained 

in  the  previous  notes  [3876a— 3833io]  ;  and  it  is  unnecessary  to  say  more  upon  the  subject 

[4283rf]    ji^  jijjg  place.     There  is  a  similar  equation  in  the  earth's  motion   [4311,  3S83i/]. 


VI.  ix.  ^^28.]  THEORY  OF  VENUS.  237 


CHAPTER    IX. 


THEORY  OF  VENUS. 


28.     If  we  put     -  =  a,      and     V     equal   to   the   geocentric   longitude      ^4284] 
of  Venus,  we  shall  find  that  the  equation  [4272], 

6r  =  —  r".  (1  —  a=) .  (5 V,  [4285] 

will  become,  relatively  to  Venus, 

^r'=.  —  r".(l— a'=).6V'.  ["286] 

Taking  for     r',     »",     tlie  mean  distances  of  Venus  and  the  earth  from  the 

sun  [4079J,  we  shall  have,  as  in  [4126],     a  =  0,72333230  ;     therefore  by      [4287] 

putting     6  V  =  ±  1"—  ±  0',324,     we  shall  obtain, 

6  r'  =  :f  0,0000007489.  [4288] 

Therefore   we  shall  neglect  those   inequalities  of  the   radius  vector  whose    ''"'"» 
coefficients  are  less  than    0,0000007.     We  shall  also  neglect  the  inequalities    .'"gLfeci 


on  account 


of  the  motion  in  longitude,  which  are  less   than  a  quarter  of  a  centesimal    "f">, 

^  ^  sinullnes*. 

second,  or     0',081. 

Inequalities  of  Venus,  independent  of  the  excentricities. 

'+  5',015931  .  sin.  {n"t  —  n' t  +  s"—  s'Y 
+11',424392  .  sm.2(7i"t  —  n' t  +  b"—  s') 
-  7%253867  .  sm.S(ti"t  —  n' t -\-  e"—  s') 

—  p-,056720  .  smA(n"t  —  n!  t  +  /'—  /) 
iV  =  {\+  O  .  (  _  Q,  345898  .  sin.5(n"^  -  n' t  +  ."-  0  >  ^'''""^ 

—  0%  145382  .  sin.6(w"  t  -  n' t  +  a"—  £') 

—  0',069726  .  sin.7(n"«  -  n' t  +  s"—  s') 

—  0%036207  .  sln.^n"t  —  n' t  -\-  e"-  i') ^ 

VOL.  III.  60 


238 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


+  (1  +  n 


0%079908  .  sin.  (n'"t . 
0%  105987  .  sm.2(n"'t  ■ 
0^010853.sin.3(n"'/ 
0',002332 .  sm.4>(n"'t . 


n't  +  £'"  —  £') 
n't  +  s"'-s') 
n't  +  i"'  —  0 


[4289] 


Inequali- 
ties inde- 
pendent of 
the  ex- 
centrici- 
tias. 


+  (l+f^'0- 


2% 891 136  .  sin.  (n'^t  —  n' t  +  >—  =') 
0%877624  .  sin.2(n'^i  —  n't  +  s'^— s') 
0',040034  .  sin.3(?i'^i  —  n't  +  s"—  .') 
0',002754  .  sin.4(n'^i  —n't  +  e'"—  s') 


0%  190473.  sin.  (n't- 
+  (1  +  'O  •  <!  —  0',039859  .  sin.2(«^^ 
- 0',00 1306.  sin. 3(n^r 


[4290] 


ir'  ^   (1+f.'"). 


—  0,0000003145 
+  0,0000038362  .  cos.  (n"t  -  n't  +  s"-  s') 

I  +  0,0000165050  .  cos.2(n"^  —  n't  +  .-"—  i') 

—  0,0000140155  .  cos.3(n"t  —  n't  +  s"—  i')  \ 

—  0,0000024255  .  cos.4(n"  t  —  n't  +  s"—  i') 

1  —  0,0000008873  .  cos.ô{n"t  -  n't  +  /'-  e')  i 
-  0,0000004021  .  cos.6(n"^  —  n't  +  s"_  e')  I 

—  0,0000002033  .cos.7(n"^  —  n't  +  ;"_  s') 

—  0,0000001094  .cos.8(n'7  -  n't  +  s"—  =') 


'—0,0000003106 

-  0,0000048903 .  cos.  (n'^t  —  n't  +  s"—  i') 

+  (1  +  \^")  .  /  —  0,0000021911  .cos.2(n''^  —  n't  +  ^'—s') 

1  _  0,0000001 155 .  cos.3(?i'^^  —  n't  +  s'"— e^ 

_  0,0000000098  .  cosA{nH  —  n't  +  b"-—  ,') 


*  (2590)     The  values       5v',     &r'     [4289,4290],  were  computed   from  the  formulas 
"'     [4277a, 6],  accenting  the  symbols  as  in  [4277c],  so  as  to  conform  to  the  present  case. 


the  excen- 
tricitiei. 


VI.  ix.§28.]  THEORY  OF  VENUS.  239 

InequttlUies  depending  on  the  first  potoer  of  the  excentricities* 

i  r'  =  (1  +  ,a)  .  0% 800933  .  sin.(2 n't  —nt  +  2s'—s  —  ^) 

0',073206  .  sin.  {n"t  +  ;"  —  ^') 

—  OM  27720  .  sin.  (7ft  +  s"  —  ^") 
-I-  0^1631 15  .  sin.  (2  n"t  —  n't  +  2  s"  —  s'  —  ^') 

—  0',  1 1 3443  .  sin.  (2  n" ?  —  n'f  +  2  s"  —  a'  —  ^,") 

/  Inequalt 

—  1  ',549550  .  sin.  (3  n"i  —  2  w'<  +  3  e"  —  2  s'  —  z^')  "'',<'•>■ 

^  \  I  /  I  pending 

+  (1  +  (..")  .  /  +  4',766332  .  sin.  (3  n"t  —  2  n't  +  3  s"  —  2  .='  — ^")  )  pp'-'r' 

\       '  '  V  '  '    /  the  excen 

—  0^299478  .  sin.  (4>n"t  —  3n't  + 4^ b"  —  3 s'  —  ^') 
+  0',947648  .  sin.  (4 n"t  —  3 n'i  +  4 e"  —  3  ='  —  t.") 

—  0',69 1 744  .  sin.  (5  n"  f  —  4  n'  i  +  5  a"  —  4  -='  —  ^') 
+  2',  196527  .  sin.  (5  n"t  —  4 n'i  +  5  s"  —  4  /  — ^")  /  [4991] 
+  0%  106435  .  sin.  (3  n'  t  —  2n"t  +3^  —  2  b"—  ^') 

—  (1  +  P-'")  .  P,092755  .  sin.  (3  71'"  t  —2n't  +  3  a'"— 2/— ^"') 

—  P,503893  .  sin.  {n'H  +  3'"—^'^) 
0%32n08  .  sin.  (2  n'^t  —  n't +  2  b'"—  s'  —  a') 

'   ^     '  '^  ^  \  ^  0',232430  .  sin.  (2  n'-'i  —  n'^ +  2  a''— /  —  a-) 

—  0',163470  .  sin.  (3  n'^t  —  2  n't +  3 b"—  2 b'—^'^) 

—  (1  +  ,a')  .  0%218743  .  sin.  (n"  t  +  b^  —  z-^)  ; 

6  r'  =  (1  +  (.)  .  0,0000008831  .  cos.  (2  n'i  —  n  ^  +  2  /—  a  —  ^) 

r   0,00000 1 6482  .  cos.  (3  /t"  «  —  2  n'  <  +  3  a"  —  2  /  —  îj")  y 
+  (1  4-^")  .<^_ 0,00000 11406  .  cos.  (5n"t  —  An't  +  5a"  —  4s'  — «')>  ^^^^^^ 
(+  0,0000036421  .  cos.  (5n!'t  —  A  n't  -{-5^'  —  4a'  — ^"); 

—  (  1  _^  ijJ"  )  .  0,0000019404  .  cos.  (3  n'"  t— 2  n't -^3  a'"  —  2  £'  —  ^"'). 

*  (2591)     The  terras  of  &v',  Sr'  [4291,4292]  are  computed  from  the  parts  o(  S  v,    or 
[1021,  1020]   depending   upon  the    excentricities     e,     e';     in    the    same   manner  as  the     [4291o] 
calculation  is  made  for  Mercury  in  [4278a]. 


240  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

Inequalities  depending  on  the  squares  and  products  of  tivo  dimensions 
of  the  excentricities  and  inclinations  of  the  orbits. 

.5  v'  =  —  (  1  +  ,;.)  .  0',333596  .  sin.  (4^n' t —  2nt -{- 4,s'—2  £ —39"  30"  30') 
(      1%505036  .  sin.  (5  ?i"t  —  3n't+ôs"—3  s'  +  20'' 54" 260  > 

[4993]  —  (1  +  •/)  .{  } 

-       ^  ^    ^     ^    l^  0',089351  .  sin.  (4  n"t  —  2  n'  i  +  4  s"—  2  s'  +  26"  66'"  32')  ) 

i„c^uai,-       +  (  1  +  //"  )  .  2^009677  .  sin.  (3  n"'t—    n'  t  +  3  /"—    s'  +  65"  53'"  09'). 

tie3  of  the  '        V  '      '  ^  '  V  '  '  / 

secund 

order.  rj,j^^  mean  motions  of  Mercury,  Venus,  the  earth  and  Mars,  bear  such 

proportions  to  each  other  that  the  quantities     2n  —  5n',     5  n" — 3n'  and 

[4393]  n' — 5 n'"  are  very  small  in  comparison  with  n';*  hence  it  follows  from 
the  remarks  made  in  [3732,  &c.],  that  the  preceding  inequalities  [4293] 
are  the  only  ones  of  the  order  of  the  square  of  the  excentricities  which 
can  become  sensible. 

Inequalities  depending  on  terms  of  the  third  order,   relative  to  the  powers 
and  products  of  the  excentricities  and  inclinations  of  the  orbits. 

[4294]       ,5  Î)'  =  (1  +  M-)  .  r,184842  .  sin.  (2nt  —  5  n't  +  2s  —  5e'  +  30"  13"' 36'). t 

Inequali- 
ties of  Ilic  ,  n    TT  •         1       •         1 

"'''•'  Inequalities  of  the  motion  of  Venus  m  latitude. 


order. 


The  formulas  of  ^  51.  Book  I.  giv^ej 


n 


*  (259-2)       The    values     [4076A]    give,     very    nearly,         2  »  —  5  7i'=  72^  =  -  ; 

[4293a]    5n"— 3  7/  =  50^=  -  :      «' —  3  «'"=  12=' =  -?^  :     all    of    which    are    small.        The 

13  '  54  ' 

first    of   these    gives       4?i' — 2n       nearly   equal    to       — ti',       and   corresponds    to    tlie 

first    form    mentioned   in   [3732].       The    second  quantity      5  n" — 3  )i',      and  the  third 

n' —  3  »'",      being  nearly  equal  to  zero,  correspond    to  the  second   form  [3733].        The 

[4293fc]    terms  of    àv'     [4293]  corresponding  to  these  quantities  are  to  be  computed  from  [3715], 

and  reduced  as  in    [4282/i— Z].      The    term  depending  on     An"  t  —  2  n' =  300°  ==  Jn' 

nearly,  is  computed  for  the  same  reasons  as  that  in  [4310']. 

t  (2593)      This    is    obtained    from     [3817],    reducing    the    several   terms  to  one,  as 
t^^^^^l    in  [4282A-Z]. 


[4295a]         X  [2594)      If  we  change,  in  [1030],     n,  a,  e,     n',  a',  i',     into     n',  a,  s,     n",  a",  i 


VI.ix428.]  THEORY  OF  VENUS.  241 

0%124804.sin.(n"<  +  £"_0 


6s'=—(l+t^"). 


4-  0',090932 .  sin.  (2  n"t  —    n't +2  s"- 
+  0',073443 .  sin.(3  n"t  —  2  n't +  3  s"—  2  e' 
+  0S081481 .  sin.  (4  n"t  —  3  nV  +  4  /'—  3  s 
+  0',312535 .  sin.(5  n"t  —A  n't +  5  s"—  4  s 
—  0',078119.sin.(2n'i—    n"t  +  2i'—    s"— è') 


Ineqoali- 
tioi  in  tbe 
latitude. 


-0 
-0 

—  '•')    \  [4295] 


[42956] 


—  (1  +  ix"')  .  0%148701  .  sm.(3n"'t—2n't  +  3  ê'"  —  2  s  — n'") 
+  (1  +(x'"').0%161414.sin.(2n'7-n'^+2«'^  — f'-n"). 


respectively,  we  shall  obtain  the  value  of  5  s'  corresponding  to  Venus  disturbed  by  the 
earth  ;  and  by  neglecting  the  term  containing  the  arc  of  a  circle  n  t  without  the 
signs  of  sine  and  cosine,  as  is  done  in  [1051]  ;  also  excluding  i  =  0  [1028,  &ic.]  from 
the  sign     2,     we  get. 

In  this  formula,     y     [1026']    represents  the   inclination,  and     n     the  longitude  of    tlie 

ascending  node  of  the  orbit  of  the  disturbing  planet,  above  that  of  the  disturbed  planet. 

These    quantities    for  the  earth's    action   upon    Venus    are,  nearly       y  =  tang.  q>',       and 

n=  \ëO''-{-è'  •     (p'     being  the  inclination  of  the  orbit  of  Venus  to  the  fixed  orbit  of  the 

earth  ;  and     è'     the  longitude  of  the  ascending  node  of  the  orbit  of  Venus  upon  that  of  the     [4295d] 

earth  [4082,408.3].      For  Mars    they  become     /",     n'";     for  Jupiter     y'%     U",     he. 

In  the  expression  [42956]  we  must  include  all  positive  and  negative  integral  values  of    i,     [4295c] 

except     1=0     [1028,  &;c.].      The  values  of    y,     /,     &c.     II,     n',    &ic.  are  deduced 

from  those  of    cp,     <p',     kc.     é,     è',     Sic.   [4082,  4083]  ;  by  means  of  formulas  similar  to 

those  in   [4282o].       Thus   if  we  wish  to  find  the  part  of    5  s'     depending  on  the  angle    [4295/"] 

2n"t  —  n't.     we  must  put     i=2,     in  [42956],  and  the  term  in  question  becomes, 

Now  the  factor     n'^— (2n"— n')2  =  4  n".(n'  — n")  ;     also    B'''^  =  ~  .  b'''.^        [1006]; 

a  •>         <j 

substituting  these  and     y,     n     [4295c],  in  [4295^],  it  becomes, 


[4295c] 


-m'.n'Ka'^a"        6f.tang.  m' 


m.{2n"i—n't  +  2^'-^—6') 


2  4rt".(n'— n").a"3 

(.-,  [4295;.] 

VOL.  III.  61 


242  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


[4295'] 


n'"  being  here  the  longitude  of  the  ascending  node  of  the  orbit  of  Mars 
upon  that  of  Venus,*  and  n'"  the  longitude  of  the  ascending  node  of  the 

If  ill  this  we  substitute     m"  ^l^'     [4061],     n"=:  1295977',     ?»'=  2106641'  [4077], 

[42951"]        (1)  „'  .  ,  ,         . 

63=8,871894    [4132],     —  =  0,72333230  [4126],      <p' =  3'^  23"" 35'     [4082];     it  is 
J  a 

[4295;t]     reduced  to       —  0',090932.(1  +  fx").  sin.(2n"<  — n'^  + 2  s"— s' -  â'),    as  in  [4295].     In 
the  same  way  we  may  compute  other  terms.      If  we  suppose     i=  1,     there  will  be  found 

two  corresponding  terms  in  [4295i]  ;  namely, 

[4995/]  -^J^l.,   •  ^  •  tang- ?'•  1 1  —  ^«" ^-  ^'^^  ■  sin-  («" <  +  s"—  «'}• 

to) 
But  by  changing     a'     into     a",  in  [1006],  to  conform  to  this  case,  we  have     a" ^ B''°'' ^  b ^i 

[4295m]     j^gjjpg  thg  preceding  expression  becomes     -^ — ^  •  (~)   •  ^''ng-  <p'  •  (  1 — 2-^3)-        If 

a'  W) 

use  the  values  of    m",   n',    n",     -     [4295i"]  ;   also     6  3^  =  9,992539     [4132];      we    get 


to) 

3' 

2 

we 


[4295n] 


(0) 

0',031231,     for  the  part  independent  of    b  ^  ;       and        — 0',156035,        for    the     part 

(0) 

depending  on      b  ^  ;       the  sum  is      — 0^,124804  .  sin.  (71"  < -{"'" — ^')  >       ^^  '"  '''^    ^'^^ 


line  of  [4295]. 


*  (2595)  A  small  inequality  in  the  mean  motion  of  Venus,  depending  on  terms  of  the 
fifth  order  of  the  powers  and  products  of  the  excentricities,  has  lately  been  discovered  by 

rAvjQni  Mr.  Airy,  arising  from  the  action  of  the  earth  upon  that  planet.  This  inequality  affects  the 
mean  motion,  the  radius  vector,  tiie  perihelion,  the  excentricity,  and  the  latitude  ;  its  period 

[429661  is  nearly  239  years  ;  being  the  time  required  for  the  argument  8  7it — 13  «"^  to  increase 
from    0'     to     360''.      This  appears  from  the  values  of    n',     n"     [4077]  ;  from  which  we 

[429Gf]     get     8  m'  —  1 3  7i"  =  5427' =  — —     nearly;   and  as  this  quantity   is  very  small,  it  follows 

that  tlie  mean  motions  of  Venus  and  the  earth  must  be  affected  by  inequalities,  depending 
upon  the  argument  8n'<  —  13?i"^;  in  like  manner  as  the  mutual  attraction  of  Jupiter  and 
Saturn  produces  the  great  inequalities  of  these  planets  in  [1 196, 1204]  ;  supposing  the  accents 
on  the  letters  a,  n,  &ic.  to  be  increased  to  conform  to  the  present  notation,  and  putting 
i'  =  8,  i"  =  13.  The  variations  in  the  excentricities  and  in  the  motions  of  the  perihelia, 
similar  to  tiiose  of  Jupiter  and  Saturn  [1298  —  1302],  are  in  the  present  case  nearly 
insensible.  The  inequalities  of  the  mean  motions  of  Venus  and  the  earth,  ^',  ^"  depending 
'  on  the  argument  8n'i — 13  n"^,  are  of  the  order  13 — 8  :=  5  [957^'",  &c.],  or  of 
the  fifth  order  nlative  to  the  powers  and  products  of  the  excentricities.       Now    e,    e"   are 

[4296/]    both  quite  small,  so  that  the  largest  of  them    e"    gives    e"*  =       .  .r    nearly  ;  but  this 


VI.ix.§28.]  THEORY  OF  VENUS.  243 

orbit  of  Jupiter  upon  that  of  Veaus. 


very  minute  fraction  is  multiplied,  in  [1 1 97] ,  by      .^J,'^'^  =3 X 13 X (239)''=  2200000    [4296^] 

nearly,  in  finding  the  value  of   ^"  ;     and  by  this  means  the  correction  is  very  much  increased. 
The  theory  and  numerical  computation  of  this  inequality  are  given  by  Mr.  Air)',in  an  elaborate 
paper  on  this  subject,  in  the  Philosophical  Transactions  of  the  Royal  Society  of  London  for    ^  '«'"*] 
1832;   using  the  data  [4061—4083];  and  putting     (x' =  —  0,045,     (ji"=0,     so  that     [4296i] 

m'=  .     He  finds  the  correction  2^  of  the  mean  motion  of  Venus,  to  be  represented  by    [4296ft] 

^r=:  {2',946-r.OS0002970|.sin.{8«^  — 13n'7  4-8s'— 13£"+220''44'»34'-M0%76|.     [429«] 

He  also  obtains  the  following  equations,  depending  on  the  same  cause,  and  similar  to  those 
Siven  in   [1298-1302]  ; 

5  b'  =  _  5',70  .  cos.(8  n't—\2n"t  +  Ss—  13  s")  ;  [4296i»] 

W=  —  0,000000190  ,  sin.(8  ?i'<  —  13n"i-\-  Be'  —  13  s")  ;  [4296n] 

5s=0',0151  .sin.(9n'i  — 13n"<  +  9£'  — 13£"  +  140''31"').  ^4296^, 

These  corrections  of    5  ro',     Se,     S  s,     may  be  generally  neglected,  as  insensible;  as  also 
that  in  the  radius  vector,  similar  to  [1197].    We  shall  give,  in  [4310c—/],  the  corresponding 
corrections  of  the  earth's  motion.     The  expressions  of   8,',    ^"  [4296Z,  43 1  Oc] ,  are  subject    t^'^^^p] 
to  the  noted  equation  [1208],  which  in  the  present  case  becomes 

7n'./a'.^'+mV«"-l"=0.  ^**^^ 


244 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


CHAPTER   X. 


THEOKY  OP  THE  EARTH'S  MOTION. 


[4296] 


[4297] 


[4298] 


29.     If  we  suppose  the  geocentric  longitude  of  Venus  to  be  represented 

T 

by     V,      and      -,  =  <>•;      V'*     will  be  a  function  of    a     and      v'  —  v". 
Then  we  shall  have,  by  [4269], 


&\'=  — 


à  ft  .  sin.  («' —  v'') 


1— 2  a.  COS.  («'—«")  4- a2' 
which  gives,  as  in  [4272],  where     ôV    is  at  its  maximum, 

5  a. 


6V'=r  —  ■ 


l-a^» 


(4297ol         *  (2596)     In  strictness  it  is  not  the  angle     V     which  is  to  be  considered  as  a  function 
of    a     and     v  —  v''      exclusively,    but  the  angle  of  elongation      E     of  Venus,  as  seen 
from  the  earth.       This  will  appear  by  referring  to  fig-  74,  page  229  ;    supposing     M     to 
represent  the  place  of  Venus  ;  S  M  =  /,    °fSM  =  v'.     For  it  is  evident  that  the  angle  of 
elongation     E=^SEM     will  remain  the  same,  if  the  angle     ESM  =  v'  —  v"    and  the 

-^— ,  =  —     do  not  vary,  whatever  changes  may  be  made  in  the  absolute  lengths 

of  the  lines  SM,  SE.  This  inadvertence  of  the  author,  in  using  V  for  E  does  not 
however  affect  the  result  of  his  calculation  [4297.  &c.]  ;  because  the  differentials  only  of 
these  quantities  are  used  ;  and  we  have,  as  in  [4268c]    (5  V'  =  —  6  E.    Now  in  [4268,  4269] 


[42976]     ratio      a  =  -- 


[4297c] 


we  have  supposed     r"     to  be  invai-iable,  so  that  the  variation  of    —  =  a 


or 

—  =:  ô  a  ; 


[4297rf] 


substituting  this  in  [4269],  and  accenting  the  letters  r',  v',  so  as  to  correspond  to  the 
planet  Venus,  we  get  the  expression  [4297].  This  Is  reduced  to  the  form  [4298],  by  the 
substitution  of  the  maximum  value  of  the  coefficient  of  —  Sa  [4271'],  in  the  second 
member  of  [4297]. 


VI.  X.  ^^29.]  THEORY  OF  THE  EARTH.  245 

a.5r" 
Supposing     r"     only  to  vary  in     6  a,    we  have    5  a.  =^ ~  ;*  therefore,      [42t>y] 

èr"=r"MlZ^  .6Y'.  [4300] 

a 

If  we  put    6V' =  ±1"=  ±  0',324,    and  take  for    r'     and     r",    the  mean     [43001 
distances  of  Venus  and  the  earth  from  the  sun   [4079],  we  shall  get. 


6r"=  ±0,000001035. 


[4301] 


r 


[4301'] 


If  we  put     V"     for  the  geocentric  longitude  of  Mars,  and     —  =^  a,     we 
shall  have,  by  [4272],t 

6f'=—  r"'.  (1  —  a-)  .  6  V".  [4^02] 

If  we  take  for     r",     ?'",     the  mean  distances  of  the  earth  and  Mars  from 
the  sun,  we  shall  have, 

a  =  0,65630030  [4159] ; 

r'"  =  1 ,52369352  [4079]  ; 


[4303] 


Terms 


and  if  we  put     6\"' ^  ±  1"  =  ±0'.324,     we  shall  obtain,  which 

^  '  may  be 

i  /•"  =  =F  0,000001363  ;  [4304] 

neglected 

therefore,  we  may  neglect  ilie  inequalities  of     sr",      whose  coefficients  are    ofîhciT 

*  (2597)     If  we  suppose     /     to  be  invariable  in  the  value  of    a     [4296],   we   shall 
get     Ja  =  — '^=  — °^      [4299];    substituting  this  in   [4298],    we  obtain  [4300]  ; 

which    is    reduced  to    the   form    [4301],  by  the  substitution  of      âV'  =  ±l"       [4300'], 
r"  ^  I     [40r9]     and     a  ==  0,7233323     [4126]. 

t  (2598)     Venus,  being  an   inferior  planet  to  the  earth,  is  situated  in  the  same  relative 
position  as  the  earth  is  to  Mars  ;  therefore  the  equation  [4286],  which  obtains  relatively  to     [4301»] 
Venus  and  the  earth,  may  be  applied  to  the  earth  and  Mars,  by  substituting  in  [4286]  the 
value  of    a     [4284],  and  then  adding  one  more  accent  to  each  of  the  symbols  r',    r" ,    V  ; 

by    which    means    we    shall   obtain        3r"  =  —  7-'"  .  A-^V  .5  V"     [4286].        In    this    ^^g^j^^ 

case     0  V"     is  the  change  of  the  longitude  of  the  earth,  as  seen  from  Mars,  arising  from  the     t/^^Qi^^ 

increment     5  ?•"  ;     and  is   evidently  equal  to  the  increment  of  the  geocentric  longitude  of 

Mars,  depending  upon  the  same  cause,  which  is  represented  by     5\"';     hence  we  get    r43Qjj| 

^  r"==-r"'.  (\  -~\  .  0  V",  as  in  [4302]. 
VOL.  III.  62 


246  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

less  than      ±0,000001.*       JVe  shall  also  neglect  those  inequalities  of  the 
[4304']     earth^s  ^notion  in  longitude,   lohich  are  less  than  a  quarter  of  a  centesimal 
second,  or     0',081. 

Inequalities  of  the  Earth,  independent  of  the  excentricities.f 

5%290878  .  sin.    (n't  —  n"  t  +  s'—  z") 

—  6',015891  .  sm.2(n'i  —  n"  t  +  e'—  î") 

—  0%743445  .  sin.  2{n't  —  n"  t  +  i'—  /') 
.,,,,/—  0%225439  .  sin.4rn'i  —  n"  t  +  s'—  n 

'    ^  —  0S091210.  sin.5(w'^  —  n"  t  +  s'—  s") 

—  0%042805  .  sin.  Q{n' t  -  n"  t  +  s'—  .") 
-  0',022027  .  ûn.l{n't  -  n" t  +  s'—  e") 

—  0%0 12053  .  sin.  8(n'i  —  n"  i  +  i'-  =") 


[4305} 


.„.n.aii-                                          /  0',427214  .  sin.    (n"7  _  n"  t  +  s'"  —  /') 

ties  inde-  / 

p™t"-'  "'■                                       f  3^483037  .  sin.  2(n"'ï  —  n"  t  +  ^"'  —  e") 

""'"""                                         \  —  0',21 5249  .  sin.  3(n"'t  —  n"  t  +  s'"  -  ,") 
+  (1  +  f^'")  •  (  —  0',047022  .  sin.4(n"7  —  n"  t  +  s'"  —  /') 

—  0^015871  .  sin.5(M"7  —  n"  t  +  b'"  _  s") 

—  0%006458  .  sin.  6(ti"'t  —  n"t  +  £'"  —  £") 

—  0^002923  .  sin.  7(n"'t  —  n"t  +  s'"  —  s") 


+  (1  +  f^'') 


7^059053  .  sin.    {n"t  —  n"  t  +  £'"—  e") 
-  2'-,674257  .  sin.2(n'^'i  —  n"  t  +  ."—.") 

—  0',  167770  .  ûn.S{n'''t  —  n" t  +  ."—  s") 

—  0',016549  .  sin.  4(?i'"/  —  n"  t  +  5'^—  s") 


(       0S439410  .  sin.    {n't  —  n"t  +  s'—  s") 

+  (  1  4-  f^.'')  .  I  —  0',  1 1 1 0 1 0  .  sin.  2{n''t  —  n"t  +  £^—  s") 

/  —  0»,004]45  .  sin.  3(n't  —  n"t  +  s'—  /') 

*  (2599)     This   quantity,  independent  of  its  sign,   is  less  than   either  of  the   values 
[4301,4304],  corresponding  to  the  7îea?-cs<  inferior  and  superior  planets  ;    and  for  the  more 
[4304a]     distant   planets  this  degree  of  accuracy  is  more  than   is   absolutely  requisite,  in  the  present 
state  of  astronomy. 

t  (2600)     The   quantities    [4305,  4306]  are  deduced  from  [4277a,  b]  ;   accenting  the 
[4305o]     symbols  so  as  to  correspond  to  the  present  case,  and  using  the  data  [4061,  8:c.]. 


Vl.x.^^-29.]  THEORY  OF  THE  EARTH.  247 

,      0,0000015553  ^ 

—  0,0000060012  .  COS.  {n't  —  n"t  +  s'—  i")  \ 
4-  0,0000171431  .  COS.  2(n't  -  n"t  +  i'—  s") 
Ô  r"  =  (1  +  f^')  •  ^  +  0,0000027072  .  cos.  3(n't  —  n"i  +  s'—  e") 
+  0,0000009358  .  cos.  A(n't  —  n"t  +  s'—  e") 
+  0,0000004086  .  cos.  ô(n'  t  —  n"t  +  b'—  b") 
.  +  0,0000002008  .  cos.  6{n't  —  n"t  +  s'—  /')  ^ 

,—  0,0000000478 

+  0,0000005487  .  cos.    (n"'t  —  n"t  +  /"_  s") 
+  (1  4_  f.'")  .  )  +  0,0000080620  .  cos.  2(n"7  —  n"t  +  e'"—  s")  V  i„e,„,u. 

—  0,0000006475  .  cos.  S(n"'t  —  n"t  +  «"'—  ^")  \  'ifEt 

—  0,0000001643  .  cos.  4(n"7  —  n"t  +  £'"—  £") 


tricities. 


—  0,0000011581  \       [4306] 

+  0,00001 59384 .  cos.  (n^'t  —  n"t  +  é"—  e") 
+  (1  +  f^")  .  <f  —  0,0000090986  .  cos.  ^.{n^t  —  n"t  +  s'"—  f") 
'  _  0,0000006550 .  cos.  S{n'H  —  n"t  + 1"—^') 
-  0,0000000704 .  cos.  4(«'7  —  n"t  +  s'"—  s")  / 

-0,0000000580  ^ 

+  (1  -ff;^').  <[+  0,00000 10337. cos.  («7  — m"^4-£^—  z")\. 
—  0,0000003859 .  cos.  2{n't  —7i"t  +  £'—  s")) 


In  the  solar  tables  of  La  Caille,  Mayer,  La  Lande,  Delambre  and  Zach,  published  before 
the  year  1803,  the  chief  correction  of  the  radius  vector  of  the  earth's  orbit,  arising  from  the 
action  of  Jupiter,  is  given  with  a  wrong  sign  ;  in  consequence  of  taking,  for     n"t-\-s'',     the  ' 

sun's  longitude,  instead  of  that  of  the  earth,  in  finding  the  argument  corresponding  to  the 
terms  which  were  used,  namely, 

+  0,0000 1 59384  .  cos .  {n'^i  —  n"t-\-  £'"—  e")  —  0,0000090986 . cos .  2 (n-i  —  n't -f- e^'  —  e") .    [4305c  ] 

This  mistake  was  first  made  known  in  a  letter  communicated  by  me  to    La  Lande,  and    u^did} 
noticed  in  vol.  8,  p.  449,  of  the  Moiiatliche  Correspond enz  for  1803. 


248 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


Inequalities  depending  on  the  first  power  of  the  excetitricities. 


iric<iuali- 
ties  de- 
pending 
on  the  first 
power  of 
the  excen- 
tricitiea. 


[4307] 


0^075910 

—  0',  129675 
-  0',  145 179 
-0%168981 

+  1',  186390 

—  2',342956 
+  O"-,  722424 

V+  0S2 16368 


—  r,095603 
+  2, 137658 
— 0",087400  , 
+  0%661950 

—  0',  103758  , 
+  0',807 1 1 1 

—  0-,  1349 15 


+  (i+0 


sin.  (n' t  +  ^' —  z,") 
sin,  {2  n't  —  n"t  +  2  e'  —  =-"  —  ^") 
sin.  (2  n"t  —  n'i  +  2  /'  —  i'  —  z,") 
sin.  (2  n"t  —  n't +  2  /'  —  s'  —  ^') 
sin.  (3 )i" t  —  2n't  +  Ss"  —  2.'  —  ~/') 
sin.  (3 n" t  —  2  n' t-^3e"  —  2^  —  ^') 
sin.  (4 n" t  —  3n't  +  4>i"  —  3 ^'  —  z^") 
sin.  (4  n"t  —  3  n't  +  4  s"  —3  /  —  ^') 
sin.  (5  n"t  —  4  n'  i  +  5  ;"  —  4  /  — ^") 

sin.  (2  n"'ï  —  n"  t  +  2  /"  —  /'  —  ^") 
sin.  (2  n"'t  —  n" i  +  2  c-'"—  :-"  —  ^"') 
sin.  (3  n"'t  —2n"t  +  3  i'"—  2/'—  v/') 
sin.  (3  n"'t  —  2n"t  +  3 .'"—  2  ."_  ^"') 
sin.  (4  n"'t  —  3  n"  i  +  4  --'"—  3  ;"_  w"  ) 
sin.  (4  H"'t  —  3  n"  t  +  4  s'"—  3  ^"—^"') 
sin.  (5  /t"7  —  4  7i"  t  -1-  5  s'"—  4  ="— r/") 


+  (!+(-"') 


+  (1  +  O 


0',302092  .  sin.  (n'-'ï  -1-  e'"— ^") 

—  2%539884  .  sin.  {n'H  +  .="  —  j.") 

—  1%492044  .  sin.  (?  w'7  —  «'7  +  2  .>—  /'—  ^") 
+  0',606399  .  sin.  (2  n'7  —  n"t  +  2  «'"—  /'—  ^'0 

—  0',543364  .  sin.  (3  n"t  —  2n"t-\-3  s"—  2 1"—  z^"") 

—  0',  148925  .  sin.  (2n"«  —  n'^'i +  2  3"— e-—^") 
\— 0^093643  .  sin.  {2n"t  —  n"t  +2£"— j'"— ^'') 


J  —  0',359921  .  sin.  {n't  +  e^  —  ra')         > 
(  — 0',151752  .  sin.  (2  n7  —  ?i"i  +  2 s'— e"— ^")  ^  ' 


*  (2601)     The  terms  of    àv",     or"     [4307,  4308]  are  computed  as  in  the  theory  of 
'^^"'"^    Mercury  [4278«]. 


VI.x.§29.]  THEORY  OF  THE  EARTH.  249 

r_  0,0000030439  .  cos.  (3  ift  —  2  n'  ^  +  3  s"  —  2  /  —  ^")  y 

àr"=  (1  +.a').^  — 0,0000049815  .  cos.  (4»"/  —  Sn't  +  4s"  —  3  e'  —^")} 

(+  0,0000015895  .  cos.  (4ïi"/  — 3n'^  4- 4  s"  _  3e'  — ^')) 

4-  (1  +,x"')  .  0,0000017707  .  cos.  {^n"'t—Sn"t  +  4 a'"—  3 s"  —  ^"')         [4308] 

—  0,0000030410  .  cos.  (2 n'^ï—     n"^  +  2£'''—     £"  — ra")" 

4-(l  4-  f^'0.<|  +  0,0000012652  .  cos.  (27rt—    n"t  +  2e''—     e"  — ^'O! 

-0,0000018101  .  COS.  (3n''f  — 2n"^+  3s"—2s"  —  ^''')'^ 

Inequalities  depending  on  the  squares  and  products  of  the  excentricities  and 

inclinations  of  the  orbits,* 

Inequali- 

6  v"  =  (1  +  I'.')  .  r-,125575  .  sill.  (5  n'7  —  3n't  +  5-="— 3/+  21''02"'  1 8^  iVJi''' 

order. 

C  +  0^993935  .  sin.  (4  n"'t  —  2  n"t  +  4  s'"—  2  s"+  67H8"560  )       [4309] 
■^  ^    "^  ^  ^  ■  ^  +  0^351 796  .  sin.  (5  n"'t  —  3  n"t  +  5  s"'-  3  a"  +  68''  25'"  09^  )  ' 

The  mean  motions  of  Venus,  the  earth  and  Mars  bear  such  proportions 
to  each  other,  that  the  quantities  5  n"  —  3  n',  4  n'"  —  2  n"  are  small  ^^gj^-j 
in  comparison  with  n"  ;  hence  it  follows,  from  [3733],  that  the  two 
first  of  these  inequalities  are  the  only  ones  of  this  order  which  are 
deserving  of  notice.  However  we  have  calculated  the  third  ;  because 
3h"— 5?r,  being  very  nearly  equal  to  ^n",  it  is  satisfactory  to  show,  by  •[4310] 
a  direct  calculation,  that  this  inequality  acquires  by  integration  only  a  very 
insensible  value. t 


n 


[4309a] 


*    (2602)       From     [4076A]     we    get,    very    nearly,        5n"  —  3  n' =  50°  =  -  ; 

4  n"'  —  2  n"  r=  50=  =  ^  ;     .3  ?i"—  5  ?i"'  =  J  37°  =  ~.       These    angles  ought  therefore 
0  3 

to  be  noticed,  as  in  [3733]  ;  and  by  making  the  computation,  as  for  Mercury  [4282a— jp], 

we  may  reduce  the  terras,  depending  on  each  angle,  to  one  single  term,  as  in  [42S2/t  — /]. 

t    (2603)      We  have  already  mentioned,  in  [4296/;],  that  Mr.  Airy  had  discovered  an 
inequality  in  the  earth's  motion,  depending  on  terms  of  the  fifth  order  of  the  excentricities     [4310a] 
and  inclinations,  connected  with  the  angle     8 n't — 13  n"i.       He   has  given  in  the  paper 
mentioned  in  [4296A]  the    numerical  values  of  the  inequalities  of  the  mean  motion     |",    [43106] 
of  the  perihelion     ozi",     of  the  excentricity     ôe",     and  of  the  latitude     &s",     namely, 

VOL.  III.  63 


250 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Inequali- 
ties of  ihe 
third 
order. 


[4311] 


hiequali- 
tio3  ill  the 
latitude. 


[4312] 


Symbols. 


[4313] 


Inequalities  depending  on  the  powers  and  prodiccts  of  three  dimensions  of 
the  excentricities  and  inclinations  of  the  orbits. 

iv"  =  (1  +1^.)  .0',069915  .  sm.(ni— 4n"i  +  s— 4=-"+19''O2'"130.* 

Periodical  inequalities  of  the  Earth's  motion  in  latitude. 

We  find,  by  formula  [1030],t 

(  0%0991 80  .  sin.  (2  n't  —n't +  2  /'—  ;'—  è')      > 
\  0',234256  .  sin.  (4  n!'t  —  3  n't  +  4  /'—  3  ='— é')  $ 

+  (1  +  (J-")  .  0',164703  .  sin.  (2  n"t  —  n't  +  2  .--  —  s"  _  é-). 

Inequalities  of  the  Earth  depending  upon  the  Moon. 

30.     If  we  jHit 
U  =  the  longitude  of  the  moon,  as  viewed  from  the  centre  of  the  earth  ; 
v"  =  the  longitude  of  the  earth,  as  viewed  from  the  centre  of  the  sun  ; 
R  =  the  radius  vector  of  the  moon  ;  its  origin  being  the  earth's  centre  ; 
r"  =  the  radius  vector  of  the  earth  ;  its  origin  being  the  sun's  centre  ; 
m  =  the  mass  of  the  moon  ; 
M  =  the  mass  of  the  earth  ; 
s  =  the  latitude  of  the  moon,  as  viewed  from  the  earth's  centre. 


[4310c] 

[4310rf] 
[431  Of] 
[4310/] 

[4311a] 


[4312a] 


^"=  (2',059  — ^.0',0002076).sin.(8n7—  13  «"<+  8  s—  13  /'+  40''44'"34'— MO',76); 
5  ra"  =  2',268  .  sin.  (8  n't— 13  n"  /  +  8  s'  —  13  s"  +  60''  16"')  ; 
<5e"=  —  0,0000001849.  cos.(8n'<—  13  m"  <+  S  s' —  13  £"  + 60''16"')  ; 
5s"  =.  0',0105  .  sin. (8  n't  — 12  n"t-\-  8  ;  —  12  s"  —  39'' 29'"). 

*  (2604)  The  direct  calculation  of  this  inequality  can  be  made,  by  a  process  like  that 
which  is  used  for  Mercury,  in  [3881f,  &c.]  ;  but  it  is  probable  that  the  author  deduced  it 
from  the  similar  inequality  of  Mercury  [4283],  by  the  method  given  in  [3883y]. 

f  (2605)      The    terms  of    [4312]   are  computed    by   means  of  the  formula   [4295/!»]  ; 


changing,  in  the  first  place,   n,     «',     e',   into    n", 


i",    respectively.     Then  changing 


m  ,     n  ,     a  ,     s       mto 
earth  ;  or  into     m'",     n^" 
the  earth. 


a',     s',      in  computing    the   action  of  Venus  on  the 
,     respectively,  in  computing  the  action  of  Jupiter  on 


VI.x.^30.] 


THEORY  OF  THE  EARTH. 


251 


we  shall  have,  for  the  inequality  of  the  earth's  motion  in  longitude   [4052], 
produced  by  the  action  of  the  moon,* 


ôv"^  -  -.-.sin.(U—v). 


The  inequality  of  the  radius  vector  of  the  earth  [4051]  is 

ôi-"^  —  jj.R.cos.(U—v"); 

and  the  inequality  of  the  earth's  motion  in  latitude   [4053]   is 

„  m      R 


711 


The 
moon's 
action 
produces  a 
perturba- 
tion in  the 
longitude  ; 

[4314] 


in  the 
radius  ; 

[4315] 


latitude. 

[4316] 


in  the 


For  greater  accuracy,  we  must  substitute f        ——  for    —, 

expressions  of  these  three  inequalities. 

We  shall  suppose  conformably  to  the  phenomena  of  the  tides  [2706,2768], 


m 
R^ 


3S_ 

^"3  ' 


[4317] 


*  (-2606)     The  moon's  action  upon  the  eartli  produces,  in  the  radius  vector,  the  longitude 
and  the  latitude  of  the  earth,  the  ineciualilics  given  in  [4051,  4052,  4053]  ;  namely, 


m 


.  r  .  cos.(v  —  U)  ; 


m       r 
MR 


.{v-U); 


m 
Jl 


rs 


[4314a] 


and  by  comparing   the  notation   used   in    [4047,  404S],  with    that   in   [4313],  it  appears    r^^Ub] 
that  we    must  change     R,     r,     v,     U,     into     ?•",     R,    U,     v",    respectively,  to  conform 
nearly  to  the  notation  of  this  article.      By  this  means  the  preceding  expressions  become, 

m     R      .     ,-rT        „,  ™     Rs 


—  ^.R.cos.{U—v"); 
M 


M       r- 

corresponding  respectively  to  the  formulas  [4315,  4314,  4316].  In  the  original  work  the 
divisor  r",  by  mistake,  is  omitted  in  [4314],  and  inserted  in  [4315]  ;  we  have  rectified 
this  mistake. 

f  (2607)     The  radius     r     [4048]   has   for  its  origin  the  common  centre  of  gravity  of 
the  earth  and  moon.      This  is  changed  into     R,     in  [4314&],  to  conform  to  the  present 
notation  ;  but  as  the  origin  of  R  [4313]  is  in  the  centre  of  the  earth,  the  value  of  the  radius    ■■        "^ 
is  too  great,  and  must  be  decreased  in  the  ratio  of    M     to     M  -\-m;    which  is  equivalent 

M 

to  the  multiplication  of  the  perturbations    [4314  —  4316]   by  ;     or  in  other  words    [43164] 

to  change  the  divisor     M     into     M-\-7n,     in  all  three  of  these  formulas. 


252  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

S   being  the  sun's  mass.      Now,  bj  the  theory  of  central  forces  [3700],* 
we  have, 

[4318]  -^  =  n/  ;  -  =  n  -  ; 


n,t     behig  the  moon's  mean  motion;  hence  we  obtain, 


[4319] 


m  3n"2 


M+i 


[4319]     We  have  by  observation     -  =  0,0748013     [5117,  4835]  ;  hence  we  get, 

71, 


[4320] 

Mass  of      consequently. 


m  1 


the  moon. 


M+m        59,6  ' 
m  1 


If  we  suppose  the  sun's  horizontal  parallax  to  be     27",2  =  8',8,      and 
[43221      *^^®    moon's    mean   horizontal   parallax       10661"  =  3454' =  57'"  34',t    we 


[4323] 


shall  have, 

R  sun's  lior.  par. 


?• 


moon's  hor.  par.        3454,0  ' 


*  (2608)  Substituting  fi^Ji-j-m  [3709«]  in  [.3700],  then  changing  a,  n,  into 
[4318a]    Jl^     n^,     respectively,  we  get  the  first  of  the  equations  [4318],  corresponding  to  the  moon's 

motion  about  the  earth.  Changing  in  this,  iW,  m,  B,  n,  into  S,  M,  r",  n", 
[43186]    and  neglecting    M   in  comparison  with    .S',    we  get  the   second  of  the  equations  [4318]  ; 

corresponding  to  the  earth's  motion  about  the  sun.      MuUiplying  the  first  of  the  equations 

r4318cl     [■^■^■^®]' hy      „        ,     and  the  second  by    3;    then  substituting  the  products  in  [4317]  we 

set     ir?-i n2=3?j"^:    dividing  this  by    n^,    we  obtain  [43191;   substituting  in  this 

[4318rf]  ^I-\--"'  a  J        /  '  L  J  J  6 

the  value  [4319'],  we  finally  get  the  expression  of  the  mass  of  the  moon  [4321].  This 
was  afterwards  found  to  be  too  great  [4631,  1190i,  &c.],  as  we  have  already  observed 
in  [.3380 J,  &ic.]. 

Instead  of  supposing,  as  in  [2706],  tliat  the  ratio  of  the  mean  force  of  the  moon  on  the 

r.fj.g  -,    tides,  is  to  that  of  the  sun  as  .3  to  1,  we  may  express  it  more  generally  by  3(1  — |3)to  1  ; 

by   which   means    the    second    members    of  the    equations    [4317, 4319,  4320],   will  be 

[4318/]    multiplied  by     1  —  (3  ;    and  the  last  of  these  expressions  will  become  -  =    -r^rê  '■> 

[4318g-]    whence  we  get  the  following  expression,  which  will  be  used  hereafter,      —  =    —  . 

[4322a]         t  (2609)     This    parallax,  taken  for   the  mean  between   the  greatest  and  least  values, 


VI.  X.  §30.]  THEORY  OF  THE  EARTH.  253 


consequently,* 

iv"  =  _  27",2524  .  sin.  (C/—  v")  =  —  8%8298  .  sin.  {U—v")  ; 


pptturba- 
tionn  in  the 
longiliide, 


[43'24] 

or"  =  —  0,000042808  .  cos.  (U—  v").  a„d  in .h.. 


radius. 


Then  taking  for  s  the  greatest  inequality  of  the  moon  in  latitude,  which      ^43251 
wo  shall  suppose  to  be     18543'.  sin.  (f/  —  f)      [5308];      U — 0    being  the    pcnurba 

tion  of 

moon's  distance  from  her  ascending  node;  we  shall  obtain t  inlau'"' 

tude- 

6  s"  ^  —  0%7938  .  sin.  (U—è),  [432e'] 

for  the  inequality  of  the  earth's  motion  in  latitude.  We  must  add  it  to 
the  terms  of  is"  [4312],  to  obtain  the  complete  value  of  6s";  and  by 
taking  this  sitm,  with  a  contrary  sign,  we  have  the  inequalities  of  the  sun^s  utïtâde. 
apparent  motion  in  latitude.  These  inequalities  in  the  latitude  have  an 
influence  on  the  obliquity  of  the  ecliptic,  deduced  from  the  observations  of  [43'27] 
the  meridian  altitudes  of  the  sun  near  the  solstices.  They  have  also  an 
influence  upon  the  time  of  the  equinox,  deduced  from  observations  of  the 
sun,  when  near  the  equinoxes,  as  well  as  upon  the  right-ascensions  and 
declinations  of  the  stars,  determined  by  comparing  directly  their  places  in 


exceeds,  by  .33%  the  constant  quantity  in  Burg's  tables  [5603],  and  is  nearly  conformable  to 
the  resuh  given  by  La  Lande  in  *5'  1698  of  tlie  third  edition  of  his  astronomy.       For  the 
purpose  of  illustration,  we  may  neglect  all  the  inequalities  of  the  moon's  pai-allax,  except    [43'22?i] 
those  depending  on  the  moon's  mean  anomaly  ;  then  taking  the  coefficients  to  the  nearest 
second,  we  have,  from  Burg's  tables  [5603], 

J)  's  hor.  par.  =  342P'  +  187" .  cos. (mean  anom.)  -)-  10'.  cos.  (2  mean  anom.).  r4322cl 


The  greatest  value  of  this  expression,  corresponding  to  the  perigee,  or  the  mean  anom.  =  0, 
is  .3421>--f  18T"+10';  and  the  least  value,  in  the  apogee  is  342P  —  187^+10'. 
The  ?nert«  of  these  two  values  342P+ 10%  exceeds  hy  10%  the  constant  term  3421"; 
and  it  is  from  causes  similar  to  this,  that  the  difference  above-mentioned  depends. 


[4322rfJ 


*  (2610)     The  inequalities  [4324]  are  deduced  from  [4314,  4315],  by  using  the  values 
[4321,4323],  and  multiplying  the  value  of     S  v"     by   the  expression  of   the  radius  in     [4324«J 
seconds  206264%8. 


t  (2611)      Substituting   the   values    [4321,  432-3],   and    s   [4.325],  in  [4316J,  we   get 
Û  »"  [4-326]  ;  changing    M    into    M-fm,    in  all  these  calculations,  as  in  [4316e]. 

VOL.  III.  64 


[432fi<»J 


254 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Perturba- 
tion of  the 
sun  in 
declina- 
tion, 

[4328] 


and  in 
right- 
aacenston. 


[4329] 


[4329'] 


Increment  of  O's  declination  =  — 


the  heavens  with  that  of  the  sun.  On  account  of  the  great  accuracy  of 
modern  observations,  it  is  necessary  to  notice  these  inequalities.  It  is 
evident  that  this  correction  increases  the  apparent  declination  of  the  sun,  by 
the  quantity,* 

Ss" .  COS.  (obliquity  of  the  ecliptic)  _ 
COS.  (sun's  declination)  ' 

and  its  ajiparent  right-ascension  is  also  increased,  by  the  following 
expression, 

r  c  ^1      •   1  5s".  sin.  (obliquity  of  the  ecliptic)  .  cos.  (sun's  riffht-ascension) 

Inc.  of  O's  nght-ascen.  = ^^ — -, — ,    /  ,. — ~ \ 

°  COS.  (sun  s  declination) 

fVe  must  therefore  decrease,  hy  these  quantities,  the  observed  declinations  and 
right-ascensions  of  the  sun,  to  obtain  those  lohich  ivould  be  observed,  if  the 
earth  did  not  quit  the  plane  of  the  ecliptic. 


*  (2612)  Let  ECC  be  the  ecliptic,  -EQQ'  the  equator,  P  the  north 
equator;  then  if  the  earth's  latitude,  north  of  the  ecliptic,  be 
5s",  that  of  the  sun  will  be  south,  and  may  be  represented 
by  CU  =  &s"  perpendicular  to  the  ecliptic.  P  CL  Q, 
r4328al  PC'L'Q^,  are  circles  of  declination,  perpendicular  to 
the  equator,  and  L  L'  is  parallel  to  the  equator.  The 
small  differential  triangle  CLU,  may  be  supposed 
rectangular  in  L,  and  angle  LC L'=  90' — angle E  CQ^. 
Then  in  the  spherical  triangle  E  C(^,  we  have,  by 
[1345^2],  cos.i:CQ  =  sin.L  CL'=^s\n.CE  q.cos.Eq-, 
COS.  CE  q 


[43386] 


sm.ECq=cos.LCL'= 


COS.  C  Q 


Now  the  declination 


is  decreased  by  the  quantity     C  L  ;     the  right-ascension  is 

LL'  LL' 


lEqaator 


[4328c]     increased  by  the  quantity      QQ'  = 


sin.  PL 


COS.  dec. 


and  we  have 


[4328rf]  LL'=^CL'.  sin.  LCL'  =  5s"  .  sin.  CEq.  cos.  E q  ; 

hence  we  get. 


[4328e]     Increm.  dec.=  —  CL  =^—CU.  cos.  L  C  L-- 


,  „  COS.  CEQ 

OS    . 

COS.  CQ 


,     as  in  [4328]  ;     and 


I  .  ,  y-^  ^,  L  L'  sin.  C  E  Q  .cos.E  Q 

[4328/]     Increm.  nght-ascen.  Q  Q' =  -—g-  ==Ss' -^ ^,     as  in  [4329] 


COS.  dec. 


VI.  x.§31.] 


THEORY  OF  THE  EARTH. 


255 


[4329" 


On  the  secular  variations  in  the  Earthh  orbit,  in  its  equator,  and  in  the 

length  of  the  year. 

31.  We  have  given,  in  [4244,  4249,  &c.],  the  secular  variations  of  the 
elements  of  the  earth's  orbit  ;  but  the  influence  of  these  variations  on  the  most 
important  phenomena  of  astronomy  has  been  an  inducement  to  compute  them 
with  greater  accuracy,  noticing  the  square  of  the  time  t;*  supposing  t  to 
denote  the  number  of  Julian  years  elapsed  since  1750.  We  have  found  by 
the  methods  given  in  [1096  —  1126],  and  using  the  values  of  the  masses  of  [4329" 
the  planets  [4061],  that  the  coefficient  of  the  equation  of  the  centre  of  the 
earth's  orbit  is  represented  by,t 


*  (261.3)  The  values  of  e^,  tang.  «  [1109,  1110],  give  those  of  e"^,  tang,  a"; 
by  changing  the  quantities  corresponding  to  m,  into  those  relative  to  m",  and  the  contrary. 
The  formulas,  thus  found,  may  be  developed  in  series,  ascending  according  to  the  powers  of 
t,  by  Taylor's  theorem  [.3850a]  ;  hence  we  easily  deduce  the  values  of  c",  •zs",  in  similar 
forms.      The  calculation  may  also  be  made  by  the  method  pointed  out  in  the  following  note. 

t  (2614)     We  have,  by  Taylor's  theorem,  as  in  [1126'"], 


2e' 


2  de" 


=  2E+~.t  + 


dde" 
~dfi 


neglecting  the  higher  powers  of    t  ;     the  values  of    —  , 


to  the  epoch   1750.       The    differential   of 


-—  ,    -— - ,    being  taken  to  correspond 

de" 

—     [1122],  taken  according  to  the  directions 

dde" 


[4329a] 
[43296] 

[4330a] 

[43306] 
[4330c] 


in  [1126"],  or  as  in  note  768,  vol.  I.  p.  612,  and  divided  by    dt,    gives      -—  ,       m  terms 

of  e,  e',  8ic.  w,  -n',  &.c.  and  of  their  first  differentials.  Substituting  in  this  expression, 
the  values  of  these  first  differentials,  given  in  [1122,  1126],  it  changes  into  a  function  of  the 
finite  quantities    e,    c',  fee.    tn,    -s/,    &,c.  ;   and  by  substituting  the  values  of  these  quantities,    [4330(/] 

dde" 


for  the  year  1750,  given  in   [4030,4081],  we  obtain  the  expression  of 


dfi 


Moreover, 


de" 


by  similar  substitutions,  we  get  the  value  of  the  expression  of    "-^    [1122].    These  values, 

bemg  substituted  in  [4330a],  give  the  expression  of  2  c"  [4330].  The  formulas 
[4330—4360]  are  so  frequently  referred  to  in  the  work,  that  we  have  given  the  numerical 
values  in  centesimal,  as  well  as  in  sexagesimal  seconds.  The  values  given  in 
[4330,  4331,  4332],  are  altered,  in  [4610  —  4612],  by  reason  of  the  changes  in  the  masses 
of  Venus  and  Mars. 

We  have  seen  in  vol.  I.  p.  612,  note  468,  that  terms  of  the  order     m'e'     are  retained, 
and  those  of  the  order     m'e'^,     which  are  of  the  Jirst  order  relative  to  the  mass     m',    are 


[4330e] 
[4.330/] 


256  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


Coeff.  eqiia.  centre  =  2E  —  t.  0",579130  —  f  .  0",0000207446 
=  2E—t.  0%  187638  —  f  .  0',0000067213, 

2E    being  this  coefficient  at  the  beginning  of  the  year  1750,  when    t   is 
ëàrth'B       nothing.     We  have  also  found  the  sidéral  longitude  of  the  perihelion  of  tlie 
earth's  orbit,  namely,* 

Long,  perih.  of  the  earth  =  ^"+  i  •  36",881443  +  t"'  •  0",0002454382 

=  t^'  +  i .  1 1',949588  +  t- .  0  ,0000795220. 

Lastly,  the  values  of   jf,    q",    at  any  time    t,    have  been  found  respectively 
equal  to,t 

p"  =  t.  0",2.36793  +  Ï-.  0",0000665275 

=  t .  0',076721  +  t- .  O',0000215549  ; 

q"  =  —  t.  1",546156  +  t\  0,0000208253 

=^  —  t.  0',500955  +  i"-.  O',0000067474. 


[4330] 


Secular 
equations 
of  the 
earth' 
orbit. 


[4331] 


[4332] 


[4330A] 


d  e" 
[4330e-]    neglected,  in  the  expression  of    —      [1122].       If  we  suppose,  for  a  rough  estimate,  that 

e'  =  -^'^,  the  neglected  terms  will  be  of  the  order  of  j^^y  part  of  those  retained;  so  that 
the  neglected  part  in  the  coefficient  of  t  [4330],  may  be  considered  as  of  the  order 
j^X0%18763S  =0^0004,  which  is  much  greater  than  the  coefficient  of  t^  in  [4330]  : 
and  at  the  first  vjew  it  might  be  thought  strange  that  we  sliould  neglect  this,  and  yet  notice 
the  much  smaller  coefficient  of  fi,  which  is  of  the  order  of  the  square  of  the  disturbing 
masses.  But  the  reason  will  appear  very  evident  from  the  consideration,  that  when  t  is 
large,  the  term  depending  on  t^  becomes  very  great  in  comparison  with  these  neglected 
[4330i]  terms.  Thus,  iÇ  t=  2500,  the  neglected  term  0,0004 1  is  only  one  second,  while  the 
term  depending  on  t^,  exceeds  42".  Similar  remarks  may  be  made  relative  to  the 
quantities     w",    jj",    q"    [4331,4332]. 

*  (2615)     Proceeding  as  in  the  last  note,  we  may  deduce   from  [3S50«],  by  changing 
[4331a]    M  into  •zn",      ^"  =  t^"-\-  i  •  -j-/ — \~  i^^'  "TT  '  ^'^^  quantities  In  the  second  member  referring 

to  the  epoch  of  1750.       The  difierential  of     ——     [1126],  divided  by    dt,     gives    —rur 

[4331i]  i'^  terms  of  e,  e',  &c.  zs,  zi' ,  and  their  first  differentials.  Substituting  in  this  expression 
the  values  of  the  differentials  [1122,  1126],  it  changes  into  a  function  of  the  finite  quantities 
e,    e',    &:c.     -a,    -a,    Sic;     and  by  using  the  numerical  values  [4080,4081],  we  get  the 

'^      values  of      — - ,    -775-)     to  be  substituted  in  [4331a],  to  obtain  [4.331]. 

t  (2616)     The  expressions  of      —-,    -—,     are  in   [425 1  i]  ;    their  differentials  taken 


Vl.x.§31.] 


THEORY  OF  THE  EARTH. 


257 


We  have  given,  in  [3100 — 3110],  the  expressions  of  the  precession  of  the 
equinoxes,*  and  of  the  inclination  of  the  equator,  referred  to  the  fixed 
ecliptic,  and  to  the  apparent  ecliptic.  In  these  formulas,  we  have  supposed 
the  values  of    p'\     </",     to  be  given  under  the  forms 

;?"==-.  c  .  sin.  (§-f  +  (3)  ;  q"  =  ^  .  c  .  cos.  {g  t  +  ^)    [30686]. 

Moreover,  we  have  seen,  in  [1133],  that  the  finite  expressions  of  //',  ç", 
appear  under  these  forms,  and  we  may  determine,  by  the  method  explained 
in  [1098,  &c.],  the  values  of  c,  g,  p.  To  obtain  these  quantities 
accurately,  by  this  method,  we  must  know  the  correct  values  of  the  masses 
of  the  planets;  and  there  is  considerable  uncertainty  relative  to  some  of 
them,  as  we  have  observed  in  [4076,  &c.].  Therefore,  instead  of  making 
the  tedious  calculation,  required  by  this  method,  it  is  preferable  to  simplify 
it,  so  as  to  embrace  a  period  of  ten  or  twelve  hundred  years,  before  and 
after  the  epoch  of  1750  ;  which  is  sufficient  for  all  the  purposes  of  astronomy. 
We  may  easily  rectify  these  calculations  as  often  as  the  development  of  the 
secular  variations  shall  make  known,  with  greater  accuracy,  the  masses  of 
the  planets.  We  shall  give  to  the  values  of  p"  and  (f  the  following 
forms,  which  are  comprised  in  those  mentioned  in  [4334]. f 

p"  =  2.  c.sm.(^gt-\-  (3)  =  c.  sin./3 — c.cos.f3.  s'm.gt  — c.sin./3.  s\n.(g't-'r}'^)  ; 
ç"=  2.  c.cos.{gt  -|_/3)  ^  c.cos.  f3  —  c.cos.(i.cos.g( — c .  sin.  §  .  COS.  (g't-\-  ^v)  ; 

ff  being  the  semi-circumference  of  a  circle  whose  radius  is  unity.       If  we 


[4333] 


[4334] 


[4335] 


[4336] 


Assumed 
forms  of 

[4337] 

r",  1"- 


,     .      ,  1    1-    •  1     1  1  ,  ■  ddp"      ddq" 

relatively  to     t,     and  divided  by     at,     give     -tt  '  , 


dp     dp 
in  terms  oi     ---,     -; — ,    cic. 
dt       at 


—,    — ,    &:c.  ;  substitutina;  the  values  of  these  last  quantities  [11321,  we  get   -~-  ,    — -  , 
dt      dt'  '  ^  '■  L  J'         &       (^^2  '     rf<a    ' 

expressed  in  finite    terms  of    p,    p',    &;c.     q,     q',     &c.       The  values   of    p,    p',    &tc. 

q,     q',    &z;c.     are  given   in   [4251c],  in  terms  of    (jj,     cp',    &,c.     ê,     &',    &,c.  ;      and    the 

numerical  values  of  these  last  quantities,  in  the  year  1750,  are  in  [4082,  4083]  ;   hence  we 

obtain  the  numerical  values  of    p,    p',    Sic.     q,     q',    &;c.     at  that  epoch.       Substituting 


these  in  [4251  f/,e],  and  in  the  preceding  values  of 


d  dp"        d  d  q" 


we   get  tlie  numerical 


dp"      dq"       ddp"      ddq" 

values  of     — ,    -;— ,     — r^ 
dl        dt'       dt3 

in  the  general  values  of    p 


dt^  '       dfi 
-— -,     at  the  same  epoch,  1750  ;  these  are  to  be  substituted 
q"     [4250],  to  obtain  [4332]. 


*  (2617)     The  formulas,  here  referred  to,  are   [3100,  3101,  3107,  3110]. 

t  (2618)     The  three  terms  of  the  second  member  of  the  value  of    p"    or    q"    [4337], 
VOL.  III.  65 


[4332a] 
[4.332i] 

[4.332c] 
[4332rf] 

[4333a] 


258  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Ctl. 

develop  these  two  functions  relatively  to  the  powers  of  the  time     t,    we 
shall  find,  by  comparing  them  with  the  preceding  series  [4332],* 

Valuesof  c  £r  .  COS.  |3  =  —  0',076721  : 


[4338] 


[4339] 


[4337a] 


[4338a] 


[43386  ; 


eg',  sin.  f3  =  —  0',500955  ; 
cg\  cos.  [3  =  0S0000134948  ; 
cg'K  sin.  |3  =  0',0000431098. 
Hence  we  easily  obtain,! 

g  =  —  36^2808  ; 
g'  ==  — 17',7502; 
c.  sin.  f3  =  582P,308; 
c.cos.  f3  =  436%17. 


are  deduced  from  those  of  p"  or  q"  [4334],  by  changing  c,  g,  p,  respectively,  into 
c,  0,  p,  in  the  first  term  ;  — c  .  cos.  p,  g,  0,  in  the  second  term  ;  and  —  c.sin.  p,  g',  J^r, 
in  the  third  term.  Tliese  expressions  of  p",  q",  being  developed  according  to  the  powers  of 
[433/6]  f^  and  compared  with  those  in  [43.32],  give,  as  in  [4.339],  values  of  c,  p,  g,  g',  which 
satisfy  the  numerical  expressions  of  p",  q" ,  [4332],  neglecting  f,  and  the  higher 
powers  of  t  :  and  as  the  values  [4332]  will  answer  for  ten  or  twelve  centuries  from  the 
epoch,  it  will  follow,  that  the  forms  assumed  in  [4337]  will  answer  for  the  same  period,  by 
using  these  values  of    c,     p,    g,     g'. 


*  (2619)  We  have  by  development,  using  the  formulas  [43, 44]  Int.  and  neglecting  terms  of 
the  order  «^  sin.gt  =  gt;  cos.gt=l  —  hg^i-;  sm.{g't-]-iv)  =  cos.g'i  =  l — ig"^t^; 
cos.  {g't  -\-i  ■ïï)  =  —  sin.  g't  = — g't  ;     substituting  these  in  [4337],  we  get, 

p"  =  i:  .c  .  sin.  {gt  -i-^)=c  .  sin.  p  —  c.  g  t  .cos.fi — c.(l  —  i  g'^t~)  .s'm.  p 
^= —  t .  {c  g  .  COS.  p)  +  t^-{i  cg'''^.  sin.  p)  ; 

ç"=2.  c  .COS.  (^^  ~\-fi)  =  c.  cos.(3— c  .  {I  —  Ig^t-).  COS.  p  -{-  c  g' t .  s\n.  fi 
=z  t .  {eg',  sin.  p)  +  fi.  (I  cg^.  COS.  p). 

Comparing  the  coefficients  of  t,  in  these  expressions,  with  the  corresponding  ones  in  [4332], 

r4338cl     "'6   &^^'  without   any  reduction,    the    two  first  equations  [4338].       In   like  manner,  by 

comparing  the  coefficients  of  I  i^,  in  [4332,43336],  we  get  the  other  two  equations  [4338]. 

f  (2620)      Dividing   the  square   of  the   first  equation    [4338],  by  the  third,   we  get 

c  .  cos.  p  [4339]  ;  and  the  square  of  the  second, divided  by  the  fourth,  gives  c  .  sin.  p  [4339]. 

[4339a]    Now,  dividing  the  values  of    c^^.cos.p,      cg'~. s'm.fi     [4338],  by  those  of    eg. cos. g, 

eg',  sin.  p     [4338],  respectively,  and  multiplying  the   products  by  the  radius  in  seconds, 

206265%    we  get   g,    g'    [4339]. 


VI.x.§31.]                              THEORY  OF  THE  EARTH.  259 

Now  we  have  seen,  in  [3100],  that  the  precession  of  the  equinoxes  +,  relative  precessio.. 

,        ,                 ,  relative  to 

to  the  fixed  ecliptic  of  1 750,  noticing  only  the  secular  variations,  is,  'cU|,1"tf 
■I  =  /^  +  ^  +  2  .  I  [j—  1  j  .  tang,  h  +  cot.  /i  5  •  y  •  sin.  (ft  +  f3). 


[4340] 

First  form. 

To  obtain  ^  .c  .un.  {ft  -\-  ^),  we  must  increase  the  angle  gt-\-^.,  in 
2  .  c  .  sin.  {g  t  +  f3),  by  the  quantity  1 1  [3073',  &c.]  ;*  making  f  =  g-\-l 
[3113a]  ;  then  we  shall  have, 

2  .  c  .  sin.  {ft  +  f3)  =  c  .  sin.  {lt  +  f^)  —  c  .  cos.  (3  .  sin.  {gt  ^l  t) 

—  c  .  sin.  p  .  sin.  {gtJ^U  +  \^)  ; 
consequently,! 


[4341] 


[4342] 


*  (2021)  If  we  increase  the  angle  gt,  by  the  quantity  lt={f — g)  t  [3113a], 
the  function  2  .  c  .  sin.(^<  +  P)  will  become  2  .  c .  sin.  (/<-(- p),  as  in  [4341]  ;  and  the 
first  equation  [4337],  will  change  into  [4342]  ;  observing  that  we  have  ^  =  0  [4337aJ, 
in  the  first  term,  or  c  .  sin.  p  ;=  c  .  sin.  [0  .  t  -{-  js),  which  becomes  c  .  sin.  {It  -\-  p),  as  in 
the  first  term  of  [4342]. 


[43410] 


t  (2622)     The  expression    2  .  c  .  sin.  (/i  +  P)i    in  the  form  assumed   [4342],  consists 
of  three  terms.     In  the  first  of  these  terms,  the  general  symbols     c,    f,     /3,    of  the  first    [4342o] 
member,  become     c,    I,    3  ;     or  in  other  words,    f  is  changed  into    /,     while    c,     (3,    are 
unaltered  ;  and  the  corresponding  term  of  [4340]  becomes, 


[43426] 


[4342c] 


I  \  ')      Ic 

. 1  j .  tang,  h  -f-cot.  A>  .  —  .  sin.(/  t -\- ^)  ;     or  simply,     c.cot.h  .  sin.  {It  -\-  ^); 

which  is  the  first  term  of  4^  [4343],  depending  on  c.  The  second  term  of  [4342], 
—  c  .  cos.  p  .  sin.  {gt  -\-  It),  being  compared  with  the  general  expression  c  .  sin.  {ft  +  p), 
in  the  first  member  of  [4342],  shows  that  c,  /,  p,  must  be  changed  into  — c  .  cos.  p, 
g  -\-t,     0,    respectively;  and  the  corresponding  term  of  [4340]  becomes, 

'i  /     '  ,  \  II  7  )       'c  .COS.  (3        .      ,  ,    ,    , 

—  ^(^rpj— Ij-tang.A+cot.A^  .____.  sm.(^i  +  ?0  ;  [4342d] 

which  is  easily  reduced  to  the  same  form  as  the  term  of  [4343],  depending  on  the  angle 
gl-\-lt.       Lastly,  the   «Aire/  term  of  [4342],      — c  .s\n.fi  .s\n.{^t -\- It -{-\v),     being     r4342e] 
compared  with  the  general  term,  in  the  first  member  of  [4342J,  gives  for     c,    f,     (3,     the 
corresponding  expressions,      — c.sin.(3,     g  -\-h     J*,     respectively;     and  the  resulting 
terra  of  [4340]  is, 


—  ^(^;  —  l)-tang.A+cot.A^  .  ^±^ .ûu.{g' t-{-lt +  1^); 

which  is  easily  reduced  to  the  form  of  the  last  term  of  [4343].      The  two  first  terms  of 
[4340,  4343],  represented  by    It  -\- 1,     are  the  same  in  both  formulas. 


[4342g] 


260  PERTURBATIONS  OF  THE  PLANETS;  [Méc.  Cél. 

r;sft"  ^  =  It +  ?,  +  €. cot. h . sin. Qt  +  p) 

the  fixed 


ecliptic  01  7  r  n-  '\ 

1750.  ^  ^  ^  çjjg_  o  _  S  çQ^_  ^ ^_    _  ^ajj„_  /j  /  _  gij^_  (-rrt  +  lt) 

[4343]  ^^  ^  '  •^  -" 

I 


Second  — ^ .  c  .  sin.  f3  .  > cot.  h  —   ~_     .  tang,  h  i .  sin.  (g't-j-  ii-^  i'^)- 


form. 


l+g' 


[4345] 


îôfàiwe'""    Then  by  putting    V    /or  the  inclination  of  the  equator  to  the  fixed  ecliptic  of 
ediptkof     1750,  we  shall  have,  as  in  fSlOll,* 

1750.  '  '  L  J' 

[4344]  V  =  h  — ^.-.  COS.  (ft +  p). 

First  formj  J 

To  obtain     2  .  c  .  cos.  (ft  +  /3),     we  must  increase  the  angle     gt  -{-  §     in 
2  .  c  .  cos.  (gt  +  P)     by     lt\  [3073,  &c.]  ;  hence  we  shall  have, 

2  .  c  .  cos.  (ft  -j-  p)  =  c.  cos.  (I  t-i-  j5)  —  c .  cos.  f3  .  cos.  (gt  -\-  1 1) 

—  c  .  sin.  |3  .  COS.  (g't  J^lt-^-^-n)  ; 
therefore, Î 

second  J 

form.  Y   =  h  —  C  .  COS.  (I  t  +  (3)  -j-  ——  .  C  .  COS.  f3  .  COS.  (g  t  +  1 1) 

[4346]  ^^^ 

+  — -j.c.sin.  f3.cos.(^7  4-Z<  +  i^). 

[4347]     4^'    denoting  the  precession  of  the  equinoxes  relative  to  the  apparent  ecliptic. 


*  (2623)     This  is  the  same  as  [3101],  putting    V    for  the  part  of    ê,     depending  on 
[4344a]     ^    and    2  ;     or  in   other  words,  neglecting  the  periodical  terms  depending  on  the  angles 

/^  +  p',    2«,    2t)'. 

f  (2624)      This  is  done  upon  the  principles  used  in  [4341,  &.c.];    and   in  the  same 
[4345o]     manner  as  [4342]  was  deduced  from  the  first  of  the   equations  [4337],  we  may  derive 
[4345]  from  the  second  of  [4337]. 

X  (2625)     Proceeding  as  in  [4342« — ■/]  ;    and  comparing  the  general  form  of  the  first 
member  of  [4345],  with  the  three  terms  of  the  second  member,  we  find,  that     c,    f,     p, 


become,  respectively,     c,     /,     p,     in  the  Jirst  term  ;     —  c  .  cos.  p,     g  -\-  I,     0,     in  the 
second  term  ;  and  —  c  .  sin.  p,     g'  -\- I,     I  "^j    in  the  third  term, 
in  the  terms  under  the  sign    2    [4344],  we  get  the  three  terms  c 
the  first  term    h,    is  the  same  in  both  expressions  [4344,  4346]. 


second  term;  and  — c.sin.p,     g' -\- I,     I  "^j    in  the  tAirrf  term.     Substituting  these  values 
in  the  terms  under  the  sign    2    [4344],  we  get  the  three  terms  containing    c,   in  [4346]  ; 


VI.x.§31.]  THEORY  OF  THE  EARTH.  261 

and    V'    the  inclination  of  the  equator  to  this  ecUptic_;  we  shall  have,  as  in     [4347] 


recesfiion 


fjuiiy  rola- 
live  ic  the 
I  T    )  .  ^  ,      T    \  ajiparciit 

eclii»tic. 


[4348] 


[4350] 


[3107,3110],*  r^rz: 

1'  =  lt  +^  +  7^  .c.cos.  |3.  )cot. /i+  7-—  .  tana;. /t  i.  sm.  (irt-\-lt) 

+  j^—, .  c .  sin.  p  .  j  cot.  h  +  — ;; .  tang,  h  I .  sin.  (g't-^  lt+ ^r:); 

V  =  h  —  j^  .  c  .  COS.  (3  .  cos.(gt+lt)  —  j^-^, .  c.sin./3.  cos.(^7  +  /^+i*).      [««] 

The  expression  of    4-'     gives,t 

~  =  Z  +  c  ^  •  COS.  ^  .  <  cot.  /t  +  -=—, —  .  tang,  h  >  .  cos.  (£[14-1 1) 
dt  ^  I  l+g  i  ^^ 

+  c  §•' .  sin.  (3  ,  )  cot.  h  -f  — —  .  tang,  h  >  .  cos.  (g't  ~\-lt -{-^■jr). 

If  we  subtract  from  this  value  of     — -,    when  t  is  nothing,  its  value  at  any     [4350'j 

other  epoch,   and  reduce  the  difference  of  these  two  expressions  to  time  ; 
considering  the  whole  circumference  as  equal  to  one  tropical  year  ;  we  shall 
get  the  increment  of  the  length  of  the  tropical  year  since  1750.      We  see,        '     ^ 
by   this    formula,    and    by  the    differential  of  the    general    expression    of 

*  (2626)     Retaining  only  the  secular  inequalities  in     4"',     ^'     [3107,3110],   changing 
also     Ù'     into     V    [3103,  4347'],  we  get,  by  a  slight  reduction  in  the  term  of    -^J,    under    [43''''"] 
the  sign  2, 

+'  =  ^^+?  +  2.^cot.;i+j.tang.A^  .  (^-^V  c  .sm.(ft  +  fi);  [43476] 

V  =  A  +  2  .  (^-^  ^  .  c  .  COS.  (/i  +  p).  [4347c] 

In  the  terms  under  the  sign    2    [43476],  we  must  substitute,  successively,  the  values  of  the 

triplets  of  terms    c,   f,    ^,    given  in  [4342a,  c,/],  and  we  shall  obtain  [4348]  ;  observing 

I  —  f 
that  the  first  term  vanishes,  because  the  factor     — —  =  0.      In  like  manner  the  substitution 

r  ,  ['4347f] 

of  the  same  triplets  of  values  [4346a  — 6],  m  [4.347c],  gives  h  [4349]  ;the  first  term  vanishing, 

f I 

on  account  of  the  factor     =  0. 

/ 

1(2627)      The  differential  of    ■].'    [4348],  taken  relatively  to    t,    and  divided  by  rf  r,    [4349a] 
gives  [4350]. 

VOL.  in.  66 


262 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4350'"] 

[4351] 
[4351'] 

[4352] 

[4353] 

[4353'] 

[4353"] 
[4354] 


4''  [3107],*  that  the  action  of  the  sun  and  moon  changes  considerably  the 
law  of  the  variation  of  the  length  of  the  year.  In  the  most  probable 
hypothesis  on  the  masses  of  the  planets,  the  whole  variations,  in  the  length 
of  the  year,  and  in  the  obliquity  of  the  ecliptic,  are  reduced  to  nearly  a 
quarter  partf  of  what  they  would  be  without  that  action  [31 15,  31 13;y]. 

^         154",63  ^  50',  1  ; 


According  to   observation,  we  have  in  1750, 

but,  by  what  has  been  said,  we  get  at  this  epoch, | 

I 


~dr 


I  -{-eg  .  cos.  (3  .  )  cot. A  + 


l+. 


di 


tang,  h 


V 


hence  we  obtain, 

l-\r  c  g  .  cos.  I'S  .  \  cot.  h  -{■ 


1  +  ^ 


tang. /j  \  =  154",63  =  50',1. 


If  we  neglect  the  square  of  c,  in  this  equation,  we  may  substitute  for 
h,  the  obliquity  of  the  ecliptic  to  the  equator  in  1750.§  This  obliquity 
was  then,  by  observation,     26^,0796  =  23" 28'"  17  ,9  ;    hence  we  deduce,** 

I  =  155",542  =  50',396  ; 


[4350o] 

[4351a] 
[43516] 

[4352a] 


*  (2623)  Tills  difTerential  is  found  in  [3 11 8],  and  by  reducing  it  into  time,  as  in  [3118'], 
we  get  tlie  decrement  of  the  3'ear,  using  f=zg-l-l  [3113a];  or  the  increment  of  the 
year,  by  changing  its  sign,  as  in  [4350"]. 

t  (2629)  This  subject  has  ah-eady  been  discussed  in  [3113a  —  z]  ;  and  we  have  merely 
to  remark  in  this  place,  that  the  values  arbitrarily  assumed  in  [4337 — 4339]  do  not  produce 
such  essential  alterations  in  these  variations  of  ■]^',  V,  as  are  mentioned  in  [3113iy,  4351]. 
This  ditierence  is  what  might  be  expected,  taking  into  consideration,  that  the  results,  obtained 
in  [4338,  4339],  are  restricted  to  values  of  /,  which  are  less  than  1200  [4335]  ;  and  that 
for  much  greater  values  of    t,    the  results  cannot  be  relied  upon. 

t  (2630)  At  the  epoch  1750,  we  have  <;=  0  [4329"],  and  then  cos.  (gt-{-It)=l, 
cos.  {g  t  -\-  1 1  -{- ^  v)  =  cos.  ;|  ir  ^  0  ;  substituting  these  in  [4350],  it  becomes  as  in  [4352]  ; 
putting  this  equal  to    50',1   [4351'],  derived  from  observation,  we  get  [4353]. 


<§!  (2631)     The  expression  of    V    [4346]  differs  from    h,    by  terms  of  the  order     c; 
[4353a]     hence  it  is  evident  that  if  ws  neglect  terms  of  the  order    C",  we  may  substitute  indifferently, 
the  value  of    V    or    h,    for    h,    in  [4353]. 

**  (2632)     Substituting  in  [4353]  the  values  k  =  23''28'"17',9  [4353"], also  the  values 
[4354a]     of    eg.  cos. ^,    g    [4338,4339],  it  becomes,  as  in  the  following  equation,  from  which  we 
easily  obtain  the  value  of  /  [4354], 


VI.x.>,^31.]  THEORY  OF  THE  EARTH.  263 

then  we  have  in  1 750,* 

V  =  A  —  -^  .  C  .  COS.  ^  ;  [4355] 

which  gives, 

h  =  26°,0796  —  3460",3  =  23'^ 28"  \Tfi  —  1 121',  1.  [4356] 

By  means  of  these  values  we  obtain  the  following  expressions,!  [wliich  arc 
altered  in  4614  —  4617], 


/  _  0',076T21  .  cot.  23''  28"'  17%9  —  ^^7^  •  tang.  23*  28"  17%9  =  154',63.  [43346] 

*  (2633)     Putting     ^=^0     in  [4349],  it  becomes  as  in  [4355].       Substituting  in  tiiis, 
V  =  23'' 28'"  17%9  [4353"],  also  tbe  values  of    /,    g,    c.cos.p    [43.54,4339],  it  becomes,    [435Ga] 
23''  28"'  \V,9  =  A  +  1 121  ',1  ;     hence  we  get    h    [4356]. 

t  (2634)     Dividing   the   value  of    c.sin.|3     [4339]  by  that  of     c.cos.js    [4339],  we 
get     tang.|3=13,.34636  =  tang.85''42"'54";     hence     (3  =  85'' 42'" 54°' ;     substituting  this     [4357a] 
in  the  expression  of    c.sin.|3      [4339],  we  obtain      c  =  5321',.308  .  cosec.  (3  =  5837',6. 
Using  these  values  of    p,    c,    and  these  of     A,    I,    g,    g"  [4356,  4354, 4339],  we  get,         [43576] 

c.  cot.A  =  13646',3; 
.  c .  COS.  p  .  j cot.  h  —  .j^—  .  tang.  A  ^  =  —  5o52',8  ;  [4357c] 


—  -L.c.  sin.  p  .  5cot.  h  —  -^ .  tang.  hl=  —  23097%7  ; 
'+g  c  t-f-g  } 

l-\-g=z  14',115  ;     Z+^^=.32',645.       Substituting  these  in  the  third,  fourth   and  fifth 
terms  of  [4343],  we  get  the  third,  fifth  and  fourth  terms  of  [4357],  respectively.       The     [4357^^] 
term    1 1    [4343,  4354],  gives  the  first  term  of  [4357].      The  term    ^    [4343],  is  to  be 
taken  so  as  to  render    ■\,=^0    [4357]  when    «  =  0  ;     whence 

^  =  _  13646-,3  .  sin.  85'' 42"  54'  +  23097^7  =  2''38'"  9',4.  [4357e] 

In  like  manner,  we  have, 

'     .c.cos.p=1.557V3;  -L.c  .sin.p  =  8986',6  ;  [4357/] 


substituting    these    and     h     [4356],    also  the  preceding  values  [4357c],    in    [4346],   we 
get  [4.358]. 

From  the  same  data,  we  have, 

^     .  c  .  cos.  p .  <  cot.  h  -\-  — —  .  tang.  h>=  —  4333',2  ; 


i-Vs  "  d  '  l+g 


z^—,.c.  sin.p  .^cot./i  +  ,-r— ,.  tang.  A[  =  —  9499',4 
l+g  i  l+g  > 


[4.3.57e-] 


[4358] 


[4359] 


264  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

^  =  tA  55",542  +  2°,92883  +  421 1 8",3 .  sin.  (t .  1 55",542  +  95°,2389) 

—  71289",2  .  COS.  i.(100",757)  —  16521",!  .sin. (i.43",564) 
^^^^'^        =  t .  50^396  +  2''38"'09%4  +13646%3.  sin.  {t .  50^396  +  So'' 42"" 54') 

Precession  

-f,;bj;-  —  23097%7  .  cos.  {t .  32%645)  —  5352',8  .  sin.  {t .  14',1 15)  ; 

theeclip- 

ye.^"^^'"  V  =  26°,0796  —  3460",3  —  1 801 7",4  .  cos.  {t .  1 55",542  +  95°,2389)  to.""'] 

+  4806",5  .  COS.  (t .  43",564)  —  27736",3  .  sin.  (t .  100",757) 
==  23^  28"'17',9  —  1 121%1  —  5837--,6  .  cos.  (t .  50',396  +  So'  42""  54') 

+  1557'-,3 .  COS.  (t .  14%1 15)  —  8986',6  .  sin.  (t .  32',645)  ; 

i'  =  f .  155",542  +  2°,92883  —  29288",3  .  cos.  t .  (100",757) 
—  1 3374",2 .  sin.  (t .  43",564) 
=-  t .  60',396  +  2''38'"  09^4  —  9489',4 .  cos.  (t .  32%645) 

—  4333',2.sin.(f .  14',  115); 

[Apparent! 
orbit.  J 

V'=  26°,0796  —  3460",3  .  ^  1  —  cos.  (t .  43",564)  | 

—  9769",2  .  sin.  (i .  100",757) 
=  23''28"'17',9  — 1121',l.jl  ~cos.(i.  ]4',115)i 

—  3165',2.sin.  (<.32',645). 

We  may  determine,  by  means  of  these  formulas,  the  precession  of  the  equinoxes 
and  the  obliqiiity  of  the  ecliptic,  in  the  interval  of  ten  or  tivelve  hundred  years 


[4357A]  sin.  {g  t -{- 1 1 -\- ^ -jr)  =  cos.  (^-'^  -f-  /  ^)  =  cos.  {( .  32%G45)  ; 

Z<  =  i .  50',.396.      Substituting  these  in   [4348],  it  becomes   as  in  [4359],   the  constant 
quantity    2,,    being  taken  so  as  to  make    4-'  =  0,    when    t=^0  [4359]  ;    consequently, 
t*^^^'^  ^  =  9489',4  =  2-*  38"'  9%4. 

Lastly,  by  a  similar  calculation,  we  have, 

-f^  .c.cos.p  =  — 112P-,1  ;  ,4— ,  •c.sin.3  =  — 3165',2; 

[4357i]  '  '  " 

cos.(g't-\-lt-]-h'^)=  —  sm.{g't  +  It)=  —  s\n.{t.  32^645)  ; 

substituting  these  and   [4356]  in  [4349],  we  get  [4360].      The  numerical  values,  given  in 
r4357n     [435T— 4360],  are  varied  by  the  author  in  [4614  —  4617],  on  account  of  the  changes  made 
in  the  values  of  the  masses  of  Venus  and  Mars.      We   have  already  given  the  formulas  of 
Poisson  and  Bessel,  in  [3380^,(7]. 


[4360] 


VI.x.§3l.] 


THEORY  OF  THE  EARTH. 


265 


before,  or  after  the  epoch  of  1750;  observing  to  make   t   negative,  for  any 

time   previous  to  this  epoch.       We    may  indeed  apply  the  formula  to  the 

observations  made  in  the  time  of  Hipparchus  ;  taking  into  consideration 
the  imperfections  of  these  observations. 

The  preceding  value  of    -i',    gives,  for  the  increment  of  the  tropical  year, 
counting  from  1750,  the  following  expression,* 

Increment  of  the  year  =  —  O''^000083568  .  {1  —cos.  {t .  14^1 15)  \ 

—  0''»^00042327 .  sin.  {t .  32'-,645). 

Hence  it  follows,  that  in  the  time  of  Hipparchus,  or  one  hundred  and 
twenty-eight  years  before  the  Christian  era,  the  tropical  year  was  12'*''-,326 
[=  10,65  sexages.]  longer  than  in  1750;t  the  obliquity  of  the  ecliptic  was 
also  greater  by  2832",27  =  917^66. 


[4361] 


[4362] 

[4363] 
[4363'] 


*  (2635)  Using  the  same  data  as  the  preceding  note,  we  get  the  numerical  values  of 
the  two  functions  [4362c,  (/],  expressed  in  sexagesimal  seconds.  These  are  turned  into  time 
by  supposing  the  whole  circumference,  360''=  1296000",  to  be  described  in  one  year,  or 
3g5da,s^242  ;    hence  we  have, 

c^.cos.p.  ^cot.^  +  — —  .tang.A?=  — 0',296527=:—  0''"y,000083568  ; 


c g'.  sin.  p 


jcot.  h 


■  -r—, .  tang. A ^  =—  l',501877  =  —  0''^^00042327. 


Substituting  these  and  [4357c?], in  [4350],  we  get  the  general  expression  of    -—      [4362/]  ; 

which  becomes  as  in  [4362^],  when  t^O.  Subtracting  the  first  of  these  expressions 
from  the  second,  we  get  the  increment  of  the  year  [4350'],  as  in  [4362],  corresponding  to 
any  number  t,  of  years  after  1750. 

^=1  —  0''"5',000083568  .  cos.  {t .  14',1 15)  +  0^''y,00042327  .  sin. {t .  32',645)  ; 

^  =  /  —  0'i''^00008356S. 

dt  ' 

These  numerical  values  are  altered  in  [4618],  in  consequence  of  a  change  in  the  values  of 
the  masses  of  Venus  and  Mars. 


[4362o] 

[43626] 

[4362c] 
[4362rf] 

[4362e] 

[4362/] 
[43C>2g] 
[4.3G2/I] 


t  (2636)     In  the  year  128  before  the  Christian  era,     <  =  —  128—  17.50  =  —  1878; 
substituting  this  in  the  two  terms  of  the  expression    [4362],  we    find  that  the  first  terin    [43(53„n 
becomes, —0^»y,00000069,  and  the  second,  +  ©■'"".OOOl  2396  ;  their  sum  is  O^'^OGO  12327, 
as  in  [4363]  nearly.      The  variation   of  the  obliquity  of  the  ecliptic,  in   the   same   time,    1^43(53^1 
deduced  from  [4360],  is  nearly  the  same  as  in  [436.3'],  being  expressed  by, 
—  112P,1.{1  —cos.{t.  14^115)}  —  3165,2.sin.(i.32^645) 

=  —  9^,2 +  926^9  =  917%7   nearly.  I'i363c] 

VOL.  III.  67 


equinox 

[4364] 

and  sun's 

apogee 

coincide. 


266  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

[4363"]  A  remarkable  astronomical  epoch,  is  (hativhen  the  greater  axis  of  the  earth\s 
hie'as'tro-  orMt  ivas  situated  in  the  line  of  the  equinoxes;  because  the  apparent  and  ji.ean 
Xt'the  equinoxes  then  coincided.  We  find,  by  the  preceding  formulas,  that  this 
phenomena  took  place  about  4004  years  before  the  Christian  era,  and  at  this 
epoch  most  of  our  chronologists  place  the  creation  of  the  ivorld  ;  so  that,  in  this 
])oint  of  view,  we  may  consider  it  as  an  astronomical  epoch.  For  we  have, 
[4364']     at  that  time,    t  =  —  5754  ;  and  the  preceding  expression  of    4^'    gives,* 

[4365]  ^'=  —  79'' 04™  04'; 

which  is  the  longitude  of  the  fixed  equinox  of  1750,  referred  to  the  equinox 
of  that  time  t.  The  preceding  expression  of  ra",  gives,  for  the  longitude 
of  the  perigee  of  the  earth's  orbit,  or  of  the  sun's  apogee,  referred  to  the 
fixed  equinox  of  1750,t 

^"=  80M5"'ll'. 

This  longitude,  referred  to  the  equinox  of  the  year  4004  before  the  Christian 
[4367]  era,  is  V  II '"07;  J  hence  it  follows,  that  the  time  lohen  the  longitude  of  the 
suri's  apogee,  counted  from  the  moveable  equinox,  ivas  nothing,  precedes,  about 
sixty-nine  years,  the  epoch  usually  assumed  for  the  creation  of  the  world. 
This  difference  will  appear  very  small,  if  we  take  into  consideration  the 
imperfections  of  the  preceding  expressions  of  4-'?  and  ro",  when  applied  to  so 
[4367"]  distant  a  period,  and  the  uncertainty  which  still  remains  relatively  to  the  motion 
of  the  equinoxes,  and  to  the  assumed  values  of  the  masses  of  the  planets. 


[4365'] 


[4366] 


[4367'] 


[4365a] 


*  (2637)     Putting  ^=—5754,  we  have  <  ..32'-,G45  ==  52''10"'39'; 
£ .  1 4%1 15  =  22''  33"'  SS'-  ;  t .  50»V396  =  80''  32""  59»  ; 

substituting  these  in  [4359],  we  get  the  value  of  -.j^'  [4365]. 


t  (2638)     Substituting  «"=  98''37"'16^-  [4081],  in  [4331],  it  becomes, 

[4366a]  T^"  =  98''37'"  16"  +  i .  1 1',949588  +  t^.  0^,000079522  ; 

and  by  putting  ^  =  —  5754,  it  is  reduced  to  98''37'"16'— 19''5'"58'+43"' 53"=80"50'"1I', 
as  in  [4366]. 

J  (2639)  Taking,  for  the  fixed  point,  the  equinox  of  1750  ;  the  longitude  of  the 
moveable  equinox,  and  of  the  solar  apogee,  corresponding  to  the  year  4004  before  Christ, 

[4367a]  will  be  respectively  79'' 4™  4'' ,  80''15'"lp-  [4365,4366];  the  difference  of  these  quantities 
j^rfj^jm-js     represents  the  distance  of  the  perigee   from  the  equinox   at   that  time.      The 

[4367t]  distance  of  these  points,  in  the  year  1750,  was  98'' 37'"  16'  [4081]  ;  so  that  in  the  period 
of  5754  years,  they  have  approached  towards  each  other,  by  the  quantity. 


\l.x.^31.J  THEORY  OF  THE  EARTH.  267 


Another  remarkable  astronomical  epoch,  is  that  when  the  greater  axis  of  the 


Another 
romarka- 


eurth^s  orbit,  was  perpendicular  to  the  line  of  equinoxes  ;  for  then  the  apparent    [4367"] 
ana  mean  solstices  were  united.       This  second  epoch  is  much  nearer  to  our    '"''<^°"'° 

[4368] 

times;  it  goes  back  nearly  to  the  year  1250.     For  if  we  suppose  t  =  —  500,    eq: 


uinox 
and  sun's 


the  preceding  formulas  give   90''  1  '",*    for  the  longitude  of  the  sun's  apogee,     [4368'] 
counted  from  the  moveable  equinox.      Hence  the  time  when  this  longitude    diSr'° 


was  90'',  corresponds  very  nearly  to  the  beginning  of  the  year  1249.  The 
imperfections  of  the  elements  used  in  this  calculation,  leaves  an  uncertainty 
of  at  least  one  year  in  this  result. 


[4309] 


98''37'«16'— I''  11"'7»=  97''26"'9^;  [4367c] 

being  at  the  rate  of  about    61*  in  a  year  ;  and  at  this  rate,  the  arc     fll"?"     will  be    [4367d] 
described  in  about  69  years  ;  so  that  the  equinox  and  solar  apogee  must  have  coincided  about 
the  year  4004  -[-  69  =  4073  [4367'J  before  the  Christian  era,  according  to  the  data  we 
have  used. 


[4368a] 


*  (2640)  In  the  year  1250,  we  have  ^  =  1250  —  1750  =  —  500  ;  and  for  this 
value  of  ^  we  get,  from  [4359,  4366a],  4,'=  —  6'' 57"';  z;i"  =  96''5S'";  therefore 
the  solar  apogee,  in  1250,  was  distant  from  the  equinox  of  that  time,  by  the  quantity 

96<i  58""  —  Q^  57""  =  90'^  1  "■  ;  [43686] 

and  as  the  distance  of  these  points,  in  1750,  was     98''37'"16'"     [43676],  the  variation  of 
distance,  in  five  hundred  years,  is  98''37"' 16'  — 90''  ]"■=  8''36"'  16^  being  about   61"  in  a     [4368c] 
year,  as  in  [4367rf]  ;  consequently,  the  distance  of  these  points  must  have  been    90^,  about 
one  year  before  the  year  1250,  or  in  the  year  1249. 


268  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


CHAPTER   XI. 


THEOIIY  OF  MARS. 


32.     We  have,  in  the  case  of  the  maximum  *  of    d  V", 

[4370]  6  0.  =  — (1  —o?).ôY"'; 

r" 

[4370]     supposing      —  =  a.  If  we  consider     r'"     as  the  onlj  variable  quantity  in 

a,    we  shall  have, 

ma 

[4371]  5  r"'  =  —  .  (  1  —  a=)  .  6  V". 


[4371']     If  we  take  for     r",     r'",     the  mean  distances  of  the  earth  and  Mars  from 
^S'        the  sun  [4079],  and  suppose     5  V"  =  ±  1"  =  ±  0^324,     we  shall  get, 
[4372]  5  r'"  _  ±  0,000002076  ; 

may  be 

neglected,  therefore  we  may  neglect  the  inequalities  of  the  radius  vector  r"',  whose 
coefficients  are  less  than  ±  0,000002.  We  shall  also  neglect  the  inequalities 
of  the  motion  in  Mars  in  longitude,  which  are  less  than  a  quarter  of  a 
centesimal  second,  or  0',081.t 


*  (2641)     The  earth  is  situated,  relatively  to  Venus,  in   the  same  manner  as   Mars  is, 

r4'î70  1     relatively  to  the  earth  ;  therefore  we  may  obtain     5  V"',     corresponding  to  Mars  [4370], 

from  the  calculation  made  for  Venus  in   [4297,  4298],   by  merely  changing  the  accents  on 

V,    in   [4298],  which  makes  it  become  as  in   [4370],  and  using    a    [4370'].      Now  the 

ôr"'.r" 
variation  of    a  [4370'],  considering   a,    r'",    as  the  variable  quantities  in    ôa.= ^^tj— 5 

substituting  this  in  [4370],  we  get  [4371];    and  by  putting    r"=a",     r"'=a"  [4079], 
using  also  a  [4159],    .5  V"  [4371']  ;  it  becomes  as  in  [4372]. 


[4373a] 


*  (2642)      The  values  [4373,4374]    are    computed   from   the   functions    [4277a,  6], 
accenting  the  symbols  so  as  to  conform  to  the  present  example. 


VI.  xi.  §32.] 


THEORY  OF  MARS. 


269 


Inequalities  of  Mars,  independent  of  the  excentricilies. 


6v"'^  (l+(^')- 


+  0+O 


+  (l+f^'') 


0',208754 .  sin.  (n't  —  n'"  t  +  s—  e'") 
-  0',024915  .  s\n.2 (n't  —  n'" t  +  -'—  s'") 
j  _  0',005000  .  sin.  S  (n't  —  n'"  t  +  t'—  ^"') 
(  _  0',001368 .  sin.4(n'i  —  n!"  t  +  t—  O 

6',988832 .  sin.    (n"  t  —  n'"  t  +  £"—  O 

—  0',968689  .  sin.  2(n"i  —  n'"  <  +  s"— O 

—  0',  1830 12  .  sin.3(n"  t  —  «'"f  +  s"—  s'") 

—  0',058242  .  sin.4(n"  t  —  n'"  t  +  s"—  i'"') 

—  0',023099  .  sin.  5  (n"  t  —  n'"  t  +  s"-  s'") 

—  0%010339  .  sin.  6  (n"  i  —  n'"  t  +  s"_  /") 

—  0',004992  .  sin.  7  (n"  t  —  n"'t  +  «"—  ^"') 

24S440843 .  sin.    (n''  t  —  «'"  <  +  e'"—  Z")  ~ 
—  13',598063  .  sin.2(n-''  t  —  n'"  t  +  e'"—  s'") 

—  r,l 80288  .  sm.S(n''t  —  n'"  t  +  £'"—  s'") 

—  0%172768.  sin.4(n'''ï  _  n'"  t  +  e-—  e'") 

—  0',033166  .  sin.5(n'''  t  —  n"'t  +  s"—  s'") 

—  0'-,013422 .  sin.  6  (n'"  i  —  n!"  t  +  s''—  i'") 


[4373] 


Inequali- 
ties inde- 
pendent of 
the  excen- 
tricilies. 


+  (l+(xO. 


P,343754 .  sin.    (n't- 
0^,443668.  sin.  2  (n^r 
0%023088.sin.  3(n''« 
0\001879.sin.4(n"r 


n"'t  +  5"—  e"') 

.n"7 +  £"—£'") 

n"'t  +  ^-—s"') 

■  ^"7  +  5"—  £'") 


4r"'=  (!+,.')• 


0,0000016104 
+  0,0000021 947 .  cos.  (n'  t  —  n"'t  +  e'—  e'") 
+  0,0000001972  .  cos.  2(n'i  —  n"'t  +  e'—  e'") 
+  0,000000041 8 .  cos. 2 (n't  —  n"'t  +  s'—  e'") 


[4374] 


VOL.  III. 


68 


270 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


Inequali- 
ties inde- 
pendent Oi" 
the  ex- 
centrici- 
tiea. 


[4374] 


+  (i+0 


0,0000023860 
—  0,0000187564, 
+  0,0000052387. 
+  0,0000011969. 
+  0,0000004169. 
+  0,0000001733. 
+  0,0000000796. 


COS.  (n"t- 
COS.  2(?^"^ 
COS.  3(?^"^ 
COS.  4(n"r 
COS.  5(n"f  ■ 
COS.  G(n"t  ■ 


Inequali- 
ties de- 
pending 
on  the  first 
power  of 
the  excen- 
tricilies. 


[4375] 


+  (l+f^'0 


^—0,0000066174 
+  0,0000784371 

—  0,0000679436 

—  0,0000069390 

—  0,0000010930 

—  0,0000002004 , 


.  COS.  (n'^t  • 

.cos.2(n'7 

.cos.3(nH 

.cos.4(n'7- 

.  cos.  5  (n'7  • 

—  0,0000000520 .  cos.  6  (n'^  - 


if't  +  ^'—f) 
■  n"'t  +  i"—i") 
.n"'t-\-i"—s"') 
.n"'t  +  s"—s"') 
.n"'t  +  i"—s"') 

n"'t  +  s"—  £'") 


.  ,t"7  +  £■"— s'") 
-  n"7  +  £"— s'") 
-?i"7-|-e"— /") 

.«'"ï  +  ii"' — s'") 

.n"7  +  s»_/") 


+  0+^^^) 


—  0,0000003173 
+  0,0000047062 

-0,0000023275 
'  —  0,0000001399 

-0,0000000125 


.cos.     (tft- 
.cos.2(nU- 

.COS.3(M^^ 

.  cos.4(w''^ 


.  n"'t  + 1"— 
.n"'t  +  s"— 


£'") 
£'") 

n 


Inequalities  depending  on  the  first  power  of  the  excentricities. 


^   1  ',082545  .  sill.  (2 /*'" ?  —n't +  2  ='"—  s'  —  ^"') 
\  —  0S252586  .  sin.  (2  n'"  i  —  w'  ï  +  2  s'"  — .-'_  z=') 


0%698649  .  sin.  («,'7  +  e"  —  ^"') 

—  0',  134530  .  sin.  (2  n'7  —  7i"'t  +  2  s"  —  /"  —  t;^'") 

—  10',  1 14699  .  sin.  (2  n"'f  —  n"t  +  2  s'"  —  -="  —  ^"') 
-  5%  1 23062  .  sin.  (2  n"7  —  ?z"/  +  2  s'"  —  .="  —  ^/'  ) 

+  (1  +  p.")  .  (  —  6^516275  .  sin.  (3  n"'t  —  2  jz"i  +  3  /"  —  2 ."  —  3.'") 
+  0',846004  .  sin.  (3  tft  —  2  n"t  +  3  s"'  —  2  ="  —  ^"  ) 
+  0',677748  .  sin.  (4  n"'t  —  3  n"t  +  4  s'"  —  3  ^"  —  ^"') 

—  0',0791.55  .  sin.  (4  n"'t  —  3  n"^  +  4  s'"  —  3s"  —  t.") 
,  +  0',1 19926  .  sin.  (5  n"'t  —  4  n"t  +  5  /"  —  4e"  —  ^j'")^ 


VI.  xi.  §32.] 


THEORY  OF  MARS. 


271 


+  (1  +  f^'^) 


+  (t+t^')- 


,+  5',490297  .  sin.  (irt  +  s'"— î^'")    * 

—  5',367005  .  sin.  (n'^l  +  ^"  —  ^'0 
-23\552332  .  sin.  (2  «'^7  —  n"'t  +  2  5'"—  s'"—  ^"') 

■  2%593100  .  sin.  (2  w'7  —  m'"^  +  2  s"— h'"— ^'') 
+  2%296703  .  sin.  (3  n"  «  —  2  «'"  ^  +  3  s-  —  2  s'"—  ^"') 

—  3%568875  .  sin.  (3  n"  t  —  2  n"'t  +  3  e^'  —  2  e'"—  ^"') 
+  0%220149  .  sin.  (4>  n'"  t  —  3  n'" t  +  4>  s'"  —  3  s'"  —  vs'") 

'  —  0%352640  .  sin.  (4  n'"  i  —  3  n"'t  +  4  e"  —  3  s"'  —  a'") 
-  2S868651  .  sin.  (2n"'t  —     n"i  +  2  e'"—     e'^— ..'") 

—  0',204519  .  sin.  (2  n"'t  —  71'" t  +  2  s'"—  s-  —  ^") 
+  r,853159  .  sin.  {3n"'t  —  2n'''t  +  3s"'—2  e"— ^"') 
+  0',198136  .  sin.  (4>  71'"  i  —  3  n"  t  +  4>  s'"  —  3  s'"  —  z^'") 

I      0-,  143758  .  sin.  {n't  +  f"  —  ^"') 

—  0',696926  .  sin.  (Wf  +  £"  — a^) 

—  r,798071  .  sin.  (2  n-t  —  h'" i  +  2 s'  —  /"  — ^"') 
+  0',132176  .  sin.  (2  nU  —  n'"  /  +  2  s'  —  s'"  — z^^) 

—  0',100246  .  sin.  (3 n't  — 2  71'" t  +  3  £"  —  2 .'"  —  ^') 

—  0',  156784  .  sin.  (2  n"'t  —  rft  +  2  £'"  —  £'  —  ^3'") 


\ 


â 


[4375] 


Inequali- 
lies  de- 
pending on 
the  fijsx. 
power  of 
the  exceti- 
tricities. 


C      0,0000044700  .  cos.  (2 n"' t—n't  +  2^"  —  ^  —  ^"')  ^ 
W=(\  +  (^')-  ^_  0,00000097 13  .  cos.  (2/1'"^  —  ^'^  +  2.'"  — e' —  ^  )  ^ 

'—0,0000022865  .  cos.  (71"  t  +  s"  —  ^"') 
+  0,0000086337  .  cos.  (2  n"7  —  ?t"/  +  2  e'"—  /'  —  ^"') 
-  0,0000031269  .  cos.  (2  n"'i  —  n"^  +  2  e"'—  s"  — .,"  ) 
4-  (1  +  f.")  .  y  _  0,0000200331  .  cos.  (3  n"'t  —  2n"t  +  3  e'"—  2  s"—  ra'") 
+  0,0000025454  .  cos.  (3  n"'t  —  2n"t  +  3  e'"—  2  h"—  ^" ) 
+  0,0000030863  .  cos.  (4  7i"'t  —  3  7i"t  +  4  «"'—  3  s"—  ^"') 
+  0,0000040239  .  cos.  (4  71'" t  —  3n"t  +  4  e"'—  3  s"—  ^") , 


[4376] 


*  (264.3)     The  computation  of  the  terms  [4.375,  4376],  is  made  in  the  same  manner 
as  for  Mercury,  in  [4278a]  ;  accenting  the  symbols  so  as  to  conform  to  the  case   under     [4375a] 


consideration. 


[4376] 


272  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél 

0,0000035825  .  cos.  (n"'t  +  s'"—^'") 
—  0,0000107986  .  cos.  (n'7  +  s'"—  ^"') 
+  0,0000031431  .  COS.  (n'H  +  i"—  ^"•) 
|_  0,0000599470 .  cos.  (2  n'"/  —  n"'t  +  2  =-"—  /"—  ^"') 
_j_  n  4-  ^ivN  ^  7+  0,0000069892  .  cos.  (2  /t'^/  —  n"'i  +  2  £■'—  s'"—  «") 

^+  0,0000114352  .  cos.  (3  7rt  _  2n"7  +  36"'—  25"'— ^"') 
-0,0000169741  .  cos.  (3  n''^  —  2n"'/  +  3£"'— 2^'"- ^'^)  ' 
'—0,0000020307.  cos,  (4 w'7  —  3n"'i4-4s'''— S^'"— ^'') 
+  0,0000087307  .  cos.  (2  n"'t  —  ?i"7  +  2  s'"—  s'"—  ^"') 
y_  0,00^0063983  .  cos.  (3  n"7  —  2ra'''i  +  3s"'—  2£'^— ^"') 

—  (1  +  M-')  .  0,0000061906  .  COS.  (2  n'  f  —  n"'t  +  26"  —  £'"  —  ^"'). 

Inequalities  depending  on  the  squares  and  products  of  the  excentricities 
and  inclinations  of  the  orbits.* 

iv'"  =  _  (1  +  ^')  .  6',899619  .  sin.  {3n"'t  —  n't  +  3/"  — e'  +  65''26'"15') 

(      l',414532  .  sin.  (3  n"'t  —  n"t  +  3^'"  —  ^'  +  73"!  l'"55')      , 

Inequali-  \  / 

^'-„°f  '"<=      —  (1  +  f/-")  .  J  +  4\370903  .  sin.  (4  n't  —  2  n'7  +  4  Z"-  2  s"  +  67^49"'  0')  \ 

order.  )  ( 

(+  2^665900  .  sin.  (5  n"'t  —  3  n"t  +  5  f'"- 3  /'  +  68''23'"00) 

t4377]  /_  0',462779  .  sin.  {n''t  +  n"7  +  ^'^  +  ^"'  —  53'  07'"  48') " 

+  (1  -f  ^iv^)  _  ^ _  i.<,444i22  .  sin.  (2  n'7  +  2.-  +  60^ 07"'  02') 

+  r,295408  .  sin.  {n''t —7i"'t  +  s'"  —  s"'+  54''  41"'  32^  ' 


ïl' 

*  (2644)     Using  the  values  [4076A],  we  get  vei-y  nearly,    3  n'" — n' =  — 12°  = 


18' 


n 


[4377a]    also      .3  ?i"'  — »i"=238°,       which  is  nearly  equal    to     ii"' ;       4n"—2n"  =  5l°=~; 

[43776]     ^''"' — 3n"=  —  137'^=  —  — -     nearly.      Hence  it  is  evident,  that  if  we  proceed  in  the 

same  manner  as  in  the  computation  of  the  similar  inequalities  of  Mercury  [4282a,  &.c.  ], 
we  must  notice  the  angles  depending  on  these  coefficients,  in  computing  the  terms  of 
[4377  —  4380].  For  the  second  of  these  angles  comes  under  the  form  [3732], 
[4377c]  { ?i" -|-  (2  —  i)  .  n"  =  n'",  supposing  i  =  —  1  ;  and  the  others  under  the  form  [3733], 
supposing   successively,     i  =  —  1,     i  =  —  2,     i  =  —  3.      Lastly,    as     n"    is   small  in 


VI.  xi.  §32.] 


THEORY  OF  MARS.  273 


The  last  of  these  expressions  may  be  connected  with  the  following  inequality, 
computed  in  [4373],  and  which  is  independent  of  the  excentricities, 

(1  +  (.'^■)  .  24-,440843  .  sin.  (71"  t  —  n"'t  +  e-'  _  s'")  ;  [4378] 

their  sum,  by  reduction,*  gives  the  following  term  of    ov'", 

^  ^■"  =  (1  +  ;V')  .  25%211710  .  sin.  (n'^t—  n'" t  +  £'"—  s"'+  2'^  24"'110.  [43^^] 

We  have  also, 
<5  r'"  =  —  (1  +  f^')  •  0,0000023461 .  cos.  (3  ir!"t  —  n't  +  3/"—  3'  +  64''47'"  29^      îp^u.. 


second 
order. 


[4380] 


0,0000050403  . cos.  (3  n"'t  —  ii't  +  3 s'"—  3"  +  72" 47'" 00') 
+  (1  +  (.") .  j  +0,0000070248. cos. (4 n"7  — 2«"i+46"'— 2-="— oB^ol'-'oO') 
-  0,0000075032 .  cos.  (5  n"'t  —3n"t+  5  s"'—3^"—  68"  27'"280  ^ 

(  +0,0000080002 .  cos.  (2  n^'t  +  2  s'^  +  60''  1 T"  52^)  ) 

^  ^+0,0000041488.cos.(?t'7  — «"'i  +  s'"  — 5"'  +  59''8'"570^ 

The  last  of  these  quantities  may  be  connected  with  the  following  inequality, 
which  is  independent  of  the  excentricities  [4374], 

(1  +  fx")  .  0,0000784371  .  cos.  {n"t  —  n'"  ^  +  s'"  —  £'"  )  ;  [4381] 

their  sura  gives  the  following  term  of    6  r'", 

&r"'=  (1  +  (^'') .  0,0000806432  .  cos.  {n"t  —  n"'t  +  £'"  —  £'"  +  2''31'"550.         [4382] 

The  inequalities   of  the  motion  of  Mars,   in  latitude,   are  hardly  sensible. 


comparison    with     n'",      their   sum      w"'  +  «"',      is   very  nearly   equal   to     n'",     so  that 

this  angle  comes  under  the  form  [3732]     in"-\-{2 — i).n"',      supposing      i^l;      and    [4377rf] 

produces  the  term  of  [4377],  depending  on  the  angle    ?«"'<  +  n"'t.      If  we  suppose    i^2, 

in  the  same  expression  [4377(/],  it  becomes   2(i'*';    now,  as  this  is  small  in  comparison  with 

n'",  it  comes  under  the  form  [37.3.3],  and  produces  the  terms  of  [437T,  4380],  depending  on 

the  angle  2n"t.     The  quantity    n'"  —  n'"    differs  but  little  from    — n"' ,  and  comes  under 

the  first  form  [3732],  depending  on  the  angle    n'H  —  n"t   [4377,  4380]. 

*  (2645)     The  term    ( I  +  (x-) . 24',440843  .  sin.  («'''  t  —  n'" i  +  s'^'  —  s'")   [4373]  may 
be  added  to  the  term     (1  +  |x'^)  .  l-,295403  .sin.  (m'>7  — ?r<  +  e-— s"'+ 51'' 41"'32^); 
and  the   sum   reduced    to  one  single   term   [4379],   by  a   calculation    similar    to    that  in    [43o0a] 
[4282^  —  /].       In    like    manner  the  terms  of    [4374,  4330],   depending    on   the  angle 
n^"  t  —  r\!"t,    may  be  reduced  to  one  single  term  of  the  form  [4382]. 

VOL.  III.  69 


274  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


[4383] 


[43840] 


[43846] 


Putting  n"  equal  to  the  longitude  of  the  ascending  node  of  Jupiter's  orbit 
upon  that  of  Mars,  we  find,* 


(  0',094394  .  sin.  («-"^  +  e'"  —  n")  ) 

[4384]  dr=n+^").^  y      ^  J  f 

^  ^    ^0%403269.sin.(2n''i  — n"'i  +  2£"'— s-'—n'")^ 


*  (2646)  The  term  of  5  s'",  depending  on  the  attraction  of  Jupiter,  maybe  derived  from 
the  formula  [4295è],  by  adding  two  accents  to  the  quantities  s',  a',  n',  s',  a",  n",  s",  m"; 
also  supposing  y  to  represent  the  incUnation,  and  II  the  longitude  of  the  node  of  Jupiter's 
orbit  upon  that  of  Mars  [4295c].  The  terra  independent  of  2  produces  the  first  term  of 
[4.384],  and  the  term  under  the  sign    2,    corresponding  to    i  =  2,    gives  the  second  term  ; 


using     -B^''=-^3  -K    [1006,4190]. 


VI.xu.§33.]  THEORY  OF  JUPITER.  275 


CHAPTER    XII. 


THEORY  OF  JUPITER. 


33.     The  reciprocal  action  of  the  planets,  upon  each  other,  and  upon  the 
sun,   is  most  sensible    in  the   theory  of  Jupiter  and   Saturn  ;   and  we  shall    [4384'] 
now  proceed  to  show  that  the  greatest  inequalities  of  the  planetary  system 
depend  on  this  cause.     The  equation  [4371], 


6r"'  =  y.(l-a=).6V"', 
r 

corresponding  to  Mars,  becomes  for  Jupiter, 


[4385] 


6  r'''  =  !L  .  (1  —  a')  .  6  V".  [4386] 

r 

If  we  take  for    r",    r'",    the  mean  distances  of  the  earth  and  Jupiter  from 

the  sun  [4079],  and  suppose     6  V''=  ±  1"=  =t  0',324,     we  shall  obtain, 

6  r"  =  =F  0,0000409225.  [4387] 

Therefore  we    may  neglect  the  inequalities    of     6  r",      which    are    below 

q=  0,000041.       We  shall  also  omit  the    inequalities  of  Jupiter's  motion  in     [4387] 

longitude,  or  latitude,  which  are  less  than  a  quarter  of  a  centesimal  second, 

or  0',081. 

Inequalities  of  Jupiter,  independent  of  the  excentriciiies* 

Itiequah' 

^^       ^^    ,    „^    (       0'-,  120833.  sin.    (n"t —  n'^'t  +  s" —s-)^  [.^^ntr 

iV      =   (1   +f^    )  .  <  >  the  ex- 

^  ^— 0,000086.  sin.  2  (n"Z  —  n'''i  + ^"  —  ^'0)  "''"'"' 


ceotrici- 
tics. 


*  (2647)     The  inequalities   [43S8,  43S9],  are  deduced  from  [4277a,  J],  increasing  by 
four   the  accents   on   the    symbols,  to   conform    to    the    present  case,  and  using    the  data 


276 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  CéJ. 


[4388] 


iaequalî- 
ties  inde- 
pendent of 
the  excen- 
tricities. 


[4389] 


+  (1  +  f^O  •  X 


+  (l+^'0 


82',8117n. 

-  204',406374 . 

—  17%071564, 

—  3',926329 , 

—  P,2 10573. 

—  0',428420 . 

—  0%  170923, 

—  0  ,076086 . 

—  0%041273. 

P,051737. 

—  0',427296 . 

—  0',044085 . 

—  O',005977 , 


sin.  (jCt  ■ 

sin.2(M'^ 

sin.3(J^^^ 

sin.4(n'^ 

sin.5(?i''^- 

.  sin.  6  (ii"  t  ■ 

.  sin.  1  (n't- 

.  sin.  8{n''t- 

.  sin.  9  (n''  t  ■ 

sin.  [n'"t  ■ 

sin.2(n"7 

sin.3(n"7- 


■  n"t  -\-  s'—i") 

■  n''i  +  e" — e'^) 
.  n"t  -\-  b' —  e'^) 

n'^t  +  6" — i") 

n"  t  +  e" —  £'") 

•  n^t  +  b" — £'") 

.n'''t  +  ^'-'—é") 

.  n"  t  +  £'■' —  i'") 

n"t  +  e"'— £") 


àf 


—  0,0000620586 
+  0,0006768760. COS.  {n't— n"t +  b^— b") 

—  0,0028966200 .  cos.2(ift  —  n"t  +  £'—  b") 

—  0,0003021367 .  cos.  3  {nH  —  n"t  +  b'—  e'") 
r^    1  v^  /— 0,0000782514. cos.4(îi"ï  — n'7  +  s"— e'M  - 

\—  0,0000258952 .  cos.  5  {n^'t  —  n''t  +  «"  —  «'")  | 

-  0,0000094779 .  cos.  6  (?j"  ^  —  n''t  +  £^—  s'")  | 

-  0,0000037560.  COS. 7  (?i^7  —  n'U  +  £^  —  s")  | 
-0,0000014781  .cos.8(»i^^  — ?ri  +  E"— ^'O  ' 

-  0,0000004799 .  cos.  9  (ift  —  n'-t  +  «"—  '^'O 


Inequalities  depending  on  the  first  poiver  of  the  excentricities. 

Several  of  these  inequalities  are  of   considerable  magnitude,  so  that  it 
becomes  necessary  to  notice  the  variations  of  their  coefficients  ;  which  we 


[43886] 


[4061,  &1C.].  The  term  depending  on  sin.  {n''  t  —  n'U  -{- b"  —  b'"),  being  computed,  by 
means  of  the  formula  [4277n],  is  found  to  be  nearly  the  same  as  in  the  first  line  of  this  page, 
and  has  the  same  sign  ;  therefore  the  remark  made  in  the  Philosophical  Transactions  for 
1831,  page  65,  that  the  sign  of  this  coefficient  is  negative,  is  incorrect. 


VI.xii.§33.] 


THEORY  OF  JUPITER. 


277 


shall  do,  in  those  terms  of  the  expression  of  6«"  which  exceed  100",   or 

32',4.      The  coefficients  of  the  inequalities  depending  on    a'',    have  for  a 

factor  the  excentricity  e"  ;*   therefore,  by  putting  one  of  these  coefficients 

Se'" 
equal  to    Ae'",    its  variation  will  be     Ae'".  -^.     We  shall  find,  in   [4407], 

that  if  we  include  even  the  quantities  depending  on  the  square  of  the 
disturbing  force  [4i04,&c.],  of  which  we  have  given  the  analytical  expression 
in  [3910],  we  shall  have. 


[4389'] 


[4369"] 


*  (2648)     The  terms   of    5v'\     Sr'"    [4392,4393],    were  computed   from  those    of 
ÙV,     &r     [1021,  1020],    depending    on    e,     e' ;     changing    m,    a,    e,    zs,    i,    n,     into 

rlfi   nictiirnti,„ 


ni",  a",  e'",  -a'"',  e'*',  Ji'",  respectively.  In  computing  the  disturbing  force  of  Saturn, 
we  must  also  change  the  symbols  m',  a',  he.  into  m'',  a",  he.  ;  and  in  computing  that 
of  Uranus,  we  must  change  them  Into  rri",  «",  &c.  We  shall  neglect  the  terms  containing 
the  arc  of  circle  nt,  without  the  signs  oi  sine  and  cosine,  as  is  done  in  [1023,  1024].  In 
this  notation,  the  angle  ra",  is  evidently  connected  with  a  coefficient  having  the  factor  e'''; 
and  the  angle  -a^,  with  the  factor  c"  ;  as  in  [4389',  4390'].  The  variations  of  c'",  e", 
are  given  in  [4407]  ;  and  if  we  retain  only  the  first  power  of  the  time  t,  they  will  be  as  in 
[4390,  4391].  For  an  example  of  the  method  of  computing  these  variations,  we  shall  take 
the  largest  term  of  ôv'"  [4392],  which  arises  from  the  substitution  of  the  value  of  i  =  2, 
in  the  term  multiplied  by  e,  or  c"  [1021]  ;  so  that  this  term  becomes. 

Substituting  the  values  of  the  elements  [4061,4077,4081],  and  that  of  jF®  deduced  from 
F'*'  [1019],  we  find  that  the  coefficient  becomes,  as  in  [4392], 

—  13S',373337  =  A  e'"     [4389']. 

ôe 
This  is  to  be  multiplied  by    —,  to  obtain  the  expression  A  (5  e'".     Now,  i5  6'"=  t .  0',329487 

[4390],  being  divided  by  the  radius  in  seconds  206265',  becomes, 

5  e''-=^.  0,00000 15974; 
dividing  this  by     e'"'  [4080J,  we  get, 

—  =  t.  0,0000.33226  ; 
multiplying  this  by    Ae"  [4390/],  we  finally  obtain, 

^JÉi^  =  — <.0',004598. 
Connecting  this  with    Ae'"  [4390/],  we  get  the  coefficient  of  the  term  depending  on  the 
angle    2  n'i— n'^< -f  2e^— e'"  — ra''    [4.392].     In  the  same  way  the  variations  of  three  of 

VOL.  III.  70 


[4390al 

[43906] 
[4390fJ 

[4390(f] 
[4390e] 

[4390/] 

[4390g] 
[4390/.  J 
[4390t'] 


278 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4390]  W"  ^t.  0',329487. 

In  like  manner,  the  coefficients  of  the  inequalities  depending  on    ^j",   have 
[4390]     the  factor    e"  ;    and  by  putting  B  e""  for  one  of  the  coefficients,  its  variation 

will  be     B  e".  ^^,     and  we  shall  find,  as  in  [4407],  that 

[4391]  0  6"=  —t.  0%642968. 

This  being  premised,  we  obtain, 


Inequali- 
ties de- 
pending 
on  tlie  first 
power  of 
the  excen- 
tricities. 


6D-=(1  +  /J.'') 


[4392] 


8',608489  .  sin. 

—  9',692385  .  sin. 
— (138',373337  +  ï 
+   (56S634099— i 

—  (44',460822  +  i 
+  (84',942569-i 
+  7%925312.sin. 
— 15',629621  .sin. 
+    r,047717  .sin. 

—  2',78 1664.  sin. 
/  +    0',407251  .  sin. 

—  0,9 13302.  sin. 
+    0',  149277.  sin. 

—  0',325592 .  sin. 

—  5',208122.sin. 

—  0%569738  .  sin. 
+  12',876650.sin. 

—  0',352399  .  sin. 
+    r,287482  .  sin. 

—  0%  172892.  sin. 
+    0-,356627  .  sin. 

—  0',083]89.sin. 


(n^'t  +  E^  —  si'') 

.  0%003 1 398) .  sin.  (2  n^  i  —  n'"  i  +  2  £^ — e'^ — ^^  ) 
.0%0014776).sin.(3n''i— 2n'^i+3i''— 2>— ^") 
.  0^0047094) .  sin.  (3n''  «— 2n"^+33''— 2.'"—  ^'  ) 

—  3  n'"  i  -f  4  £''  —  3  5'"  —  zi" 

—  3  ?i''  ;  4-  4  £"  —  3 1"  —  ra" 

—  4  n'^f  +  5  £'  —  4  s"  —  zi'" 

—  4  n''  «  +  5  6^  —  4  s'" —  zj" 

—  ôn'''t  +  6i'—ôs'"'-~-u," 

—  5n*'i  +  6s^  — ô^'"  — T.^ 

—  6n'"^  +  7£'-  — 6  e'"— 33'" 

—  6  irt  +  7  £" 6  s'"  — -n" 

—  rft  +2  £'" —     £"  —  ra'" 

—  nU  +  2  s'" —     £"  —  ra" 

—  2  71^1  +3  i"—  2  6'—  z=" 

—  2  71^1  +  S  s'"—  2  £"  —  73' 

—  3  71"^  +  4  s'"—  Si"  —  zs'" 

—  3  ?ri  +  4  s'"—  3  £'  —  ^" 

4  7ft  4-  5  t-'" 4  s'  —  z:'" 

—  4>7i''t  4- 5  £"— 4 ^^"  —  i^' 


(4  71^1 

(4^^ 

(ôn^t- 

(ÔTl't 

(6  71"  t 

(6  n"  t 

(In^t 

ÇlrCt 

(2  n'H 

(2  7l"t 

(3  n'7 

(3  n"« 

(4  n'H 

(4  7l"t 

(5  Tl'H 

(5  71" t 

the  other  large  terms  of  [4392]  are  computed.    The  variations  of  the  remaining  ones  are  too 
small  to  be  noticed. 


VI.xii.<^33.] 


THEORY  OF  JUPITER. 


279 


(1+^") 


.ir"=(l+,.-) 


0%  123506  .  sin.  (n"<  +  s^'  — x.") 

-  0',235240  .  sin.  (ti'U  +  i"'  —  ^") 

-  0',533079  .  sin.  (2  n"'  t  —  irt  +  2 1"  —  s"  —  ^") 
+  0',  102673  .  sin.  (2  ?r'/  —  n'"  t  +  2  s"'  —  i"  —  a") 
—  0'-,  127963  .  sin.  (3  n'H  —2  n"i+  3  s"  — 2i"—  i^''') 

0,00002061 1 1  .  COS.  {n'H  +  s'"—  a") 

—  0,0000795246  .  cos.  {n"  1  +  ^'  —  ra'") 
+  0,0000492096  .  cos.  (n"  i  +  s"  —  «^  ) 

—  0,0002922 130.  COS.  (2  H'i—  n''i  +  2E''—  e"— ^i' 
1+  0,000 1688085.  COS.  (2/1"  Ï—  n"t +  2t' —  'Z^"—^-' 

—  0,0004584483  .  cos.  (3  n^i  —  2n'''i+  3  £"—  2e"— x^" 
+  0,0009047822.  cos.  (3  n'i  — 2  n''7+ 35"— 26"— ^" 

j-l-  0,000 1 259429  .  cos.  (4  n'  ^  —  3  iVH  +  4  £"  —  3  s'"—  t^" 

/—  0,00024244 1 3  .  cos .  (4  n''  i  —  3  n"7  +  4  s"  —  3  s'"—  a" 

+  0,0000268383  .  cos.  (5  n'  t  —  ^n"t  +  5 s"—  4s"—  ^" 

—  0,0000516048.  COS.  (5/1"^  — 4n"i -foe"  — 4s''— ^^ 
+  0,0000579151  .  COS.  (2n''t—    nU-^2s"'—    I'  —  zs" 

I—  0,0001346530  .  cos.  (5  n'H  —  2ift  +  3  e'"—  2  s"  —  ^'^ 


Inequali- 
ties de- 
pending on 
the  first 
power  of 
the  excen- 
tricitiei). 


[4393] 


Inequalities  depending  on  the  squares  and  products  of  the  excentricities 

and  inclinations* 

l',003681  .  sin.  (n"ï +  n'^7  + e" +£"'  +  45''29"220 
—  5',578707  .  sin.  (2 nTt  +  2s"  +  15' 56"  24^ 
+  ir,724245  .  sin.  (3  ri't  —  n"t  +  3^"  —  e'"+  79-^  39"  48^ 
—1 8',075283  .  sin.  (4  n'  ^  —  2 n}H  +  4  e"—  2  e'"—  57"  1 2" 26') 
'"■•=('+-')V(,69s266896-<.0S004277).si„.(^;i-4»-|+3-^^^^^^^ 

+  P,647140.sin.  (6  n"f  — 4n"<  +  6  s"_4£'"— 64''25'"480 

+  2'-,47 6404.  sin.  (    n't—     n'"i-|-    e"—    £'"4-43^17'"0P) 

V  —  6',287997  .  sin.  (2  n"  i  —  2  n'"  i  +  2  £"—  2  e"  +  42  '4O'"440 


Inequali- 
tiei  of  the 

second 
order. 


[4394] 


*  (2649)      The  calculation  of  the  six  first  terms  in  [4394]  is  made  in  exactly  the  same 
way  as  for  Mercury,  in  [4282a  — 6].      The  coefficient  of  the  angle    3  n''<  —  5  rCt,    being    [4394a ] 


280  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

These  two  last  inequalities  being  connected  with  the  two  following, 

[4395] 

(        82',8n711.sin.    (n^ï  —  «'"  ^  +  s'— £'")  ^  _ 

*"  ^  ■  ^  _204',406374 .  sin.  2  (n't  —  n'"  t  -\-  b' —  s'")  ^  ' 

which  are  found  in  [4388],  among  the  terms  independent  of  the  excentricities, 
produce  the  terms,* 

(_  84',628936.sin.  (?ri— n^i  +  s'"  — s"  — 1''08"'530  ) 
^       ^  (+209',098224.sin.  (2?^'"^— 2n^'i+2£"'— 2  e''— r'09"'58^)^ 

Then  we  have  [4394^/], 

loequali- 

sic'oôS""'  /      0,0000822415 . cos.  (2  w^i  +  2  s"  +  1 1'OO"' 550 

order.  I  ^ 

+  0,0000226252.  cos.  (3  n-t—n'^t  +  3  s"—  s''— 21''47"'18') 
^4397^     6r''=^(l  +  f^'').(  —0,0001010533.  cos.(4?i^^—2n'"«+4î''— 2=-''— 51''04"'040 

-(0,0021 1 14502-^0,00000005323).cos.(^J;l-!J;;2o;:^ 
—  0,0000652204.  cos.  (2  ?i'7— 2rt'''<+2  e'— 2 .'"+  54''08"'52') 

If  we  connect  the  last  of  these  inequalities  with  the  following, 

—  (1  +f^")  .  0,0028966200. cos.  2(n"i  —  iV't  +  i'  —  i")  ; 

which  is  found  in  [4389],    among  the  terms  that  are  independent  of  the 
excentricities,  we  obtain  the  equivalent  expression, 

[4399J     6  r"=  _  (1  -|-  j.^)  .  0,0029251 892  .  cos.  (2  7i'H  —  2  n''t  +  2  i"—2  e^'— 1''02"'080. 

The  preceding  inequalities  of    iv'",    are  calculated  by  the  formulas  [3711, 

3715,  3728,  3729]  ;  excepting,  however,  that  which  depends  on  the  angle 

[4400]     3^'"^  —  brft\     observing  that    bn"  —  2n",    is  a  very  small  coefficient,  as 

appears  from  the  ratio  which  obtains  between  the  mean  motions  of  Jupiter 


large,  its  variations  must  be  noticed  and  computed  by  the  metiiod  pointed  out  in 
[43946]    [4017  —  4021].      The  other   coeniclents   are  less  than    32%4,    and   their    variations  are 

neglected,  as  in  [4389',  he.].  The  two  last  terms  of  [4394]  correspond  to  [3729,  3728]  ; 
[4394c]     using     i=^±l,    or    i^±2;     the  values  of  A"   being  found,  by  means  of  the  formulas 

[3753  —  3755'"],  and   the  corresponding  terms  are  to  be  connected  together,  like   those 

depending  on  M,  in  [4282A  —  /].  In  like  manner,  the  four  first  terms  of  [4397]  are 
[4394dJ    deduced  from  [3711];  the  last  term  from  [3728];  noticing  always  the  variations  of  the 

elements  in  the  greatest  coefficients,  as  is  done  with  the  terms  of  &  v. 

[4396o]         *  (2650)     This  computation  is  made  in  the  usual  manner,  as  in  [4380a]. 


[4398] 


VI.xii.§33.]  THEORY  OF  JUPITER.  281 


[4400'] 


[4401] 


and  Saturn  [4076/t]  ;  so  that  the  angle  Sn'^t  —  ôn^t  differs  but  very  little 
from  n''f,  as  in  [3712,  &c.]  ;  in  consequence  of  which,  we  have  used  the 
formulas  [3714,  3715],  in  computing  this  inequality,  by  the  method  given 
in   [4017  —  4021]. 

Inequalities  depending  on  the  poicers  and  products  of  three  and  Jive 

dimensions  of  the  excentricities  and  inclinations  of  the  orbits, 

and  on  the  square  of  the  disturbing  force. 

The    great    inequality    of    Jupiter,    is    calculated    by    the     formulas 
[3809—3868;  3910—4027].      We  find,  from  [3836—3841], 

a\  ilfw  ^  —  5,2439100  .  m'  ; 

a\M")=       9,6074688  .  m\- 

a\  M<-^>  =  —  5,8070750  .  nf  ; 

a\M'-^^=       1,1620283.  m^ 

a\  itfw  =  —  0,6385781  .  m"  ; 

a\  M' ''  -=       0,3320740  .  m\  mequaii^ 

'  tics  of  the 

Hence  we  find,  at  the  epoch  1750,*  orJ"- 

a\P=       0,0001093026; 

a\  P'  =  —  0,0010230972.  [4402] 

We  must  find  the  values  of  the  same  quantities  in  2250  and  2750.  For 
this  purpose  it  is  necessary  to  determine  the  values  of  e'",  e",  t^'",  w*',  j,  n, 
in  series,  ascending  according  to  the  powers  of  the  time  ;  continuing  the 
series  so  far  as  to  include  the  second  power  of  t.  We  must,  in  the  first  ^  ^ 
place,  calculate,  by  the  formulas  [3910  —  3924],  the  secular  variations  of 
0  e'%  ie",  5ra'',  Szs",  depending  on  the  square  of  the  disturbing  force  ;  and 
we  shall  obtain,  for  these  variations,! 


*  (2651)     The  values  of   «'P,    «^P'    [4402],  are  deduced  from  [3842,  3843]  ;  adding 
four  accents   to  the  letters    m,    a,    e,    zs,    m ,    a',    e ,    Stc.   to  conform  to  tlie   present    [4402a] 
notation,  and  then  using  the  numerical  values  [4061,  4077,4079,  4080,  fcc.]. 

t  (2652)  The  value  of  ^e'"  [4403],  is  computed  from  the  part  of  (S  e  [3910],  depending 
on  the  time  t,  without  the  signs  of  sine  and  cosine  ;  adding  four  accents  to  the  letters 
m,  a,  e,  m',  u',  e ,  &:c.  to  conform  to  the  case  now  under  consideration.      izi'"   [4403],  is 

VOL.  III.  71 


[4403a] 


282  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél, 


[4403] 


[4404] 


[4405] 


àé"  =  t.  0%052278  ; 
<!  ^"  =  t.  0^352941  ; 
ie'  =  — i.0%102763; 

61^"=       t.  3',242722. 

The  coefficients  of  t,    in  these  expressions,  represent  the  parts  of    — ,    — ^ , 
— ,    —     [4404a,  6,  c],   depending  on  the  square  of  the  disturbing  force.* 

Ut  CE  t 

Adding  them  respectively  to  the  parts  of  the  same  quantities,  determined  in 
[4246,  4247],  we  obtain  the  entire  values  in  1750, 

^^  =       0%329487  : 
'^=       6',952808; 

dt  ' 

^  =  _  0',642968  ; 

dt  ' 

^-^  =     19%355448. 
dt  ' 


obtained  from  the  like  parts  of  &-a  [3911].  The  expressions  6  e'-',  (5  a"  [440-3],  are  deduced 
from  [3922,  3923],  by  making  the  same  additional  number  of  accents  to  the  letters,  and 
then  substituting  the  values  of  these  elements  [4061,  4077,4079,  &ic.]. 

*  (2653)     We  have,  as  in  [4330rt],     e'"  ==;  e'"  +  ^ .  ~  +  J  t^.  ^ ;  e"  in  the  second 

member,  being  the  value  of  e'',  at  the  epoch  ;  and  by  putting  for  e'* —  e"',  its  value  ^e'", 
we  get, 

[44046]  5e-=<.— +  1^^^^. 

In  like  manner  we  have, 

[4404c]  6e^  =  t.^+it^'—+^o.;  6.^  =t .  -  +  if^.^  +  ^o. 

The  coefficients  of  t,  \  t^,  in  the  second  members  of  these  expressions,  correspond  to  the 
epoch.  The  coefficients  of  the  first  power  of  t,  in  these  expressions,  are  composed  of  two 
parts,  namely,  those  computed  in  [4246,4247],  and  those  depending  on  the  square  of  the 
[4404rf]  disturbing  masses,  computed  in  [4403]  ;  the  sums  of  the  corresponding  parts  give  the 
coefficients,  respectively,  as  in  [4405].     Thus, 

^  =  0%052278  +  Jx0%554418  =  0V329487,  Sic.  as  in  [4405]. 
at 


[4404a] 


VI.  xii.  <^33.] 


THEORY  OF  JUPITER. 


283 


We  obtain,  by  the  same  method,  their  values  in  1950, and  find,  at  this  epoch,* 

^=      0',326172; 
dt 


IT 

de" 
It 


=       7',053178; 
=  _  0%648499  ; 


~—  =     19^424739. 

dt 

From  these  we  get,  as  in   [3850,  &c.  3850c],  the  following  expressions  of 

e'*,    îj'",   e",    w'  ;    for  any  time  whatever  ; 

e'*  =  €'■'  +  t.  0%329487  —  f:  0^,0000082871 
z,"  =  I.-  +  / .  6^952808  +  t-.  0  ,0002509259 
e'  =€"  —  t.  0%642968  —  f:  0%0000138275 
^"  =^"  +1. 19--,355448  +  t\  0',0001 732274  : 

the  values  of   é",    to'%    e",    «%    m  the  second  members  of  these  equations, 

correspond  to  the  year  1750. 


[4406] 


General 
values  of 

TO",  -m". 

[4407] 


[4407'] 


*  (2654)     The  calculation  of  the  annual  variations  of  the  elements  [4406],  for  the  year 
1950   is  made  in  the  same  manner  as  in  [4405],  using  the  expressions  of    e'^,    e",    «'",    -a",    [4406a] 
corresponding  to  1950.      These  elements  are  obtained,  very  nearly,  by  means  of  the  annual 
decrements  [4405],  which  give,  with  sufficient  accuracy,  the  required  values,  when    t  does 
not  exceed  200.     Thus  the  increment  of  e'*',  corresponding  to    t  =  200,  is 

200X0',329487=:65',8  nearly  [4405];  |-4406J] 

being  the  same  as  the  term  depending  on  the  first  power  of  t,  in  the  expression  of  e'»  [4407]. 
The  term  depending  on  i^,  in  this  last  expression,  is  very  small,  being  represented  by 

—  2002  X  0^000008287 1  =  —  0»-,3  nearly  ;  [4406e] 

which  is  about  -^^sxs  part  of  the  term  corresponding  to  the  first  power  of  t.  Similar  remarks 
maybe  made  relative  to  the  values  of  t" ,  ra",  ■a'' .  If  these  calculations  were  to  be  repeated, 
in  consequence  of  any  changes  in  the  assumed  values  of  the  masses  of  the  planets,  we  could 
take  into  consideration  the  parts  depending  on  t'^,  as  they  are  given  in  [4407]  ;  and  by  this  [4406rf] 
means  we  might  obtain,  by  successive  operations,  corrected  values  of  the  elements.  This 
process  is  the  same  as  that  so  frequently  used  by  astronomers,  in  re-touching  and  correcting 
the  elements  of  the  orbits  of  the  heavenly  bodies. 


Now,  from  [3850c],  we  have. 


ddé" 


îiTT'^ 


in  which  we  must  substitute 


dé" 


for    -—',  its  value  0',326172  [4406]  ;  also  for  — -  ,  its  value  0',329487  [4405]  ;  hence 


[4406f] 


284  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

We  may  find  the  values  of  y,    n,    by  means  of  the  equations,* 
7  .  sin.  n  =  (p" .  sin.  ff'  —  <?'"•  sin.  o'"  ; 
^^^°®^  y  .  cos.n  =  (f" .  COS.  r  —  9'\  cos.  ê'\ 

d  y       du 

Then    we   compute  the  values  of    -—,    —,    by  taking  the  differentials   of 

J         ,      •        •         r         dq,'"        dtp"        dù'^       dè^  .     .  . 

[4408]     these  equations,  and   substitutmg  tor    — — ,    - — ,    —— ,    —,    then*  values 

[4246,  4247].     We  find,  in  this  manner,  in  1750, 

7=      IMô-'SO'; 
n  =  125"^  44"' 34'; 

^''''^  Ç  =  -   O',000106; 

dt 

~=~26%09U33. 
dt 

The   formulas    [3935,  3936]   give,  for  the  secular  variations  of    y   and   n, 
depending  on  the  square  of  the  disturbing  force, 

ij=       i.0',000184; 

in  =  — ^.0',00763. 
If  we  add  the  coefficients  of  t,  in  these  equations,  to  those  in  the  preceding 

d  y       d  TÏ. 

values  of    —  ,     —     [4409],   we  obtain,  for  the  complete   values   of  these 
quantities  in  1750, 


[4410] 


rfrffi'                0',003315               „„   ^^^„       „   ,     .      .         ,.        ,          ^  ddei^ 

[4406/"]     we  eet     ,r77Tr  = TTJ^^ —  =  —  O',0000082b / .     Substituting  this  value  of  -— -„,    and 

■'                         4di'^                       40U  2dt~ 
d  c'^ 

that  of    -7-    [4405],  in    (:"■  [4404^],  we  get  the  first  of  the  equations  [4407].  The  values 

[440tig-j     ^^  ^,v^  gv^  ^v^   g,,g  ]om;|f|  |„  ^i]g  same  manner,  changing    e"   [4404«,4406e],  successively, 
into  w",  e",  -a",  and  using  the  values  [4405,4406]. 


[4409a] 


[44096] 


[4409c] 


*  (2655)  Tlie  equations  [4408]  are  similar  to  those  in  [4282o],  adding  four  accents  to 
ç),  è,  cp',  ê',  to  conform  to  the  present  case  ;  and  changing  tang.ç)"',  tang.  9",  into  9",  ç", 
respectively,  on  account  of  their  smallness.  In  this  case  7  [3739]  represents  the  langent 
of  the  inclination,  or  very  nearly  the  inclination  itself,  of  the  orbit  of  Saturn  to  that  of 
Jupiter  ;  and  n  [3746],  the  longitude  of  the  ascending  node  of  the  orbit  of  Saturn  upon 
that  of  Jupiter.  Substituting  in  [4408]  the  values  of  9'%  é'\  ç\  é-,  [4082,  4083],  we 
get  7,  n  [4409].  Tlien  taking  the  differentials  of  [4408],  and  substituting  the  preceding 
values  of  ç)*",  è",  kc.  ;  also  those  of  do'",  de'",  df,  do"  [4246,  4247],  we  get  the  two 
last  equations  [4409],  by  making  a  few  reductions. 


VI.xii.§33.]  THEORY  OF  JUPITER.  285 

'^  =       0',000078  • 
(It 

V-=-26',101764. 

dt 


We  find,  by  the  same  process,  in  1950, 

-  0',001487; 


dy 
~dt   ~~ 

V^=— 26',402056. 

dt 


Hence  we  obtain,  by  the  method  in  [3850 — 3853],  for  any  time  whatever  t*    inciininion 

^  ,  and 

y  =  y-^t.    O',000078  —  t\  0',000003913  ;  [4413] 

n  =  n— ^ .  26',  101 764  —  t-.  0',000750731.  [4413] 

longitude 

The  values  of  y,  n,  in  the  second  memhers  of  these  equations,  correspond  to   n,  of  the 
1 750.     This  being  premised,  we  find  in  2250, f  ascending 

niideofiho 

a\P  =  —  0,0000801 89  ;  '^;:^ 

[4414] 

«'.  F  =—0,001006510;  J.H,.„f 

and  in  2750, 

a\  P  =  —  0,000260997  ; 

«^P'=— 0,000954603- 


Jupiter. 


[4415] 


*  (2656)  If  we  change  the  symbols  y,  XI  [4412],  for  the  year  1950,  into  y^,  IT, 
respectively,  and  leave  those  in  [4411],  corresponding  to  the  year  1750,  without  accents,  we 
shall  have,  as  in    [4406e], 

-^^  =  jJ^ .  $'^  -Jf\^  ^"^  •^'"  ^''001487  -  0',000078|  =—  0S00000.3913  ;        [4413a] 
also, 


'^''"  =^a^.HlL'_— |=^^^.f_26',402056  +  26',101764}  =  — 0',00075073. 


2^,2  —  tU  ■  I  -jj  —  TT  (  =î*t7-  i—  i=;o%4U2U5(j  +  '^b%1017b4|  =  — 0%00075073.        [44136] 

Substituting  these  and  the  values  of  [4411],  in  the  general  expressions  of    y,  n   [4404«], 
namely, 

we  get  [4413,4413'];  observing  that  the  values,  in  the  second  members,  correspond  to  the 
year  1750. 

t  (2657)     The   values  of    a\  P,    a'.  F',    are   given  in   [3842, 3843],  in  functions  of 
e",  e",  -a'",  ti\    y,    n,  &c.  ;  and  their  values  in  1750,  have  already  been  given  in  [4402].    [4414a] 

VOL.  III.  72 


286  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

Hence  we  deduce,  by  the  method  of  [3850—3856],* 

a\  ^=  —  0,000000387666  ; 


[4416] 


a\  '^  =-  —  0,000000002145  ; 

d  t 

a".  ^=  0,000000000034734; 
a\^=  0,000000000141280. 
The  part  of  5v'\  given  in  [4023],  is,t 


[4417] 

6v" 


.      „,  ,  ^a'^'.dP  3a'^.ddP'  )  \ 

(    .     rfP'  ,         2a"'.ddP        )    ,  ,  „     .    ddP'i  / 


Cm".  ni*-2 

~(5,V-2,i"f\  ,  2a>''.dP'  Sa'\ddP 

a'\P 


(5n^—2n>^).dt        i5n^  —  2n"f.dt^      ^ 

^  cos.(57iH—2ii'H+5s^ -2;'") 


(^    .     dP  2a<-.ddP'      )    ,    ,  2     i,ddP\ 


.    ,  ''(       '  dt       (ân-'—2n").dV2S 

G  root  *  ^  ^  '  ^ 

iiidiuiility. 

This  becomes,  by  reduction  to  numbers, 


[4418] 


6î;'^=(1263%799671—  t .  0',008418  —  <2.0'.000019247) .  sin.  (5  ii''t  —  2n"t  -{'5s'-— 2  s") 
4-  (  1 19%526S51  —  t .  0%473686  +  i^.  0-,0000:8562) .  cos.(5  n't  —  2  n"t  +  5  s^  —  2  s^'). 

The    great   inequality  of   Jupiter    includes  several    other    terms  ;     thus,   it 
contains,  in  [3844],  the  expression,! 


To  obtain    a^.P,    a\  P'    in  2250  [4414] ^  we  must  put    !!=  500,   in  [4407,4413,44131, 

[44146]      and  substitute  the  corresponding  values  of    e'",    -cj'^,  Sic.  in  [3842,  3843].     In  lilce  manner, 
by  putting   t  =  1000,  we  get  their  vakies  in  2750   [4415]. 

*  (2658)      The  values  of    «^  P    [4402,4414,4415],   being  substituted,  respectively, 

dP  d-P 

[4416a]     foj.  p^    p^    Pi,,m  [-3856],   give  the  values  of   n\--,    a\—  [4416].     In  like  manner, 

from  a^.P'  [4402,  4414,4415],  we  get  the  terms  depending  on  the  differentials  of  P'  [4410]. 

t  (2659)    The  formula  [44 17],  is  the  same  as  in  [4023] ,  increasing  the  accents  on  the 
[4418a]     elements    m,  a,  c,  &c.    m',  a',  e',  fcc.  by  four,  to  conform  to  the  case  under  consideration. 
Substituting  in  [4417],  the  values  [4402,  44 1 6] ,  it  becomes  as  in  [4418]. 

r4419al         Î  (2660)     The  expression  [4419]  includes  the  third  and  fourth  lines  of  (5  «"   [3844],  the 
accents  being  increased  as  in  the  last  note. 


VI.  xii.§:33.] 

fdP 
6V"'=  — 


THEORY  OF  JUPITER.  287 


n'V 

7M< 


To  reduce  it  to   numbers,  we  must  calculate  the  values  of  a"".  (-^  )  ; 


(hW 


a"-.  (  4-^  )?  &;c.  ;  and  we  find,* 

V  da"  J 


\da'^\ 

a''^ 

/dAP'^' 

\  '^  «"  . 

«"^ 

A?.W(3V 

\  f'"'" 

iC\ 

V  ^ 

/f/7»/('>~ 

\  f^"'"  , 

„v9 

^«/./l/ra- 

=  —  26,46390  .  m^  ; 
=  65,75870  .  m"  ; 
=  — 50,227 14.  m''; 
=  1 2, 14696.  m"; 
=  _  6,75963.  m^; 
=         4,13173.  m^ 


From  these  we  deduce  the  values  of  a^-.  (  -— ^-  j,     a'".  (  ^^  )'  ^^'  '  ^^^"^'' 

are  necessary  in  the  theory  of  Saturn,  by  means  of  the  general  equation  of 
homogeneous  functions  [1001a],t 


da'"  J  \  d a" 


[4419] 


[4420] 


d  /J/^'A  /d  1/t'A 


*  (2661)    The  accents  being  increased  as  in  [4418«],  the  formulas  [3836  —  3841]  give  the 

a'V  (2)  (3) 

valuesof   a^.W"',    a'J)f"\  &c.  in  terms  of    a:=  — ,    b,,    6 -,,  &.c.  and  their  differentials. 
Taking  the  partial  differentials  of  these  expressions  relative  to  a'",  and  substituting  the  values    [44000] 

(2-)  (3) 

[420-2-4211],  we  get  [4420].    Observing  that   hp    h^,  &c.  are  functions  of  a   [964].  and 
if  we  represent  any  one  of  them  by  h,  its  partial  differential,  relative  to  n'^,  will  be, 
/■  dh  \        fdh\      /  do.\         /db\        1 

t  (2662)       Tlie    general    values    of     M^''\      M''\      iW^^',      M'^\      M^'',      M<5> 
[3836£/,  3337c,  3838A,  3840A,  &ic.],  are  composed  of  functions  of  a'",    a",    of  the  forms, 


288  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

Hence  we  find,  in  1750,* 

a"2.  (if.  V  COS.  (5  7iV  —  2  n'^t  +  5  £"—  2  e'") 

—  a"'~.f-—A  .sin.  (5ft''<  — 2?i'''<+5  6^— 2;") 


[4422] 


2  m".  n'" 
5  Ji"—  2  n'"  '  ^  ■  „  /d  P'\ 


[4423] 


[4424] 


[4425] 


=  —  1 7%228862 .  sin. (5  n'' i— 2n'''<  +  5£'— 2 ;'0 
+    5',36001 6 .  COS.  (5  if  t  —  2  n'' <  +  5  s"—  2  r)  ; 
and  in  1950,  it  becomes, 

—  16',836801  .  sin.  (5  n" /  —  2  n''^  +  5  e^—  2  s") 
+     6^449839  .  cos.  (5  n't  —  2  n'"^  +  5  £"—  2  e"). 
Hence  we  obtain  the  following  value  of  this  function,  for  any  time  whatever  t, 

6 ?)'"=:  —  (17',228862  —  /.  0',001960)  .  sin. (5  n't  — 2 n'^t  +  b^-—2  i") 
+  (5',360016  +i.0',00o449).cos.(5n^7  — 2n"'i  +  5s^  — 2  s"'). 


all  of  which  are  homogeneous,  and  of  the  order  — 1,  in  a'^,  a"  [1001',  1007']  ;  i 
being  any  integral  number.  Hence  the  general  value  of  JJi*''  is  also  homogeneous,  and  of 
the  degree  — 1,  in  a",  a'';  and  the  formula  [lOOlo],  by  changing  A,  a,  a',  m,  into 
M^",    a'\    a",      —1  becomes  as  in  [4421]. 

*  (266-3)     The  values  of     m^n"  P,     m"  a"  P',     are  found  as  in  [4402n],  by  increasing 
[4422a]    tbe  accents  of  the  elements  in  [3842,  3843]  by  ybwr.      Taking  the  partial  differentials  of 
these  expressions,  relative  to    a'",  we  obtain  the  values  of, 

[44225]  ™'«^-C^)'  -^"-63' 


expressed  in  functions  of  a'^,  e'",  &c-  a^,  e",  &ic.  and  of  the  terms  [4420].  Substituting 
these  in  [4419,  or  4422],  we  get  [4423],  corresponding  to  the  year  1750.  Repeating  this 
calculation,  with  elements  computed  for  the  epoch  1950,  it  becomes  as  in  [4424]  ;  observing 
that  the  functions  [4420],  must  also  be  computed  and  taken  for  the  year  1950.  Comparing 
the  numerical  coefficients  of  the  terms  [4423,4424],  we  find  the  increments,  in  200  years, 
to  be  respectively  represented  by, 

—  16',8.36801  +  17^228S62=:0^392061, 

[4422i]     and 

G^449839  —  5,-360016  =  l-',089823. 

Dividing  these  by  200,  we  get  the  annual  increments,  or  the  coefficients  of  t,  as  in  the  general 
expression  of  '5 1'''   [4425]. 


VI.xii.§33.] 


THEORY  OF  JUPITER. 


289 


The  great  inequality  of  Jupiter  [3844]  contains  also  the  term,* 

ôv'''  =  —  h  He",  sin.  (on"  t  — 2  n"t-{- 5 1"  — 2  s'^—zs^"  +  A); 
which,  in  1750,  is  equal  to, 

0^820290 .  sin.  (5  1^1—2  n"  t  +  5  b"—  2  i'") 
—  1%837963 .  cos.(5  n't— 2  n"  t  +  5s''  —  2  s'")  ; 
and  in  1950,  is, 

0%701624 .  sin.  (bn''t  —  2 n" t  +  5i'—2  é") 
—  r, 840958  .  cos.  (5  n't  — 2  71" t  +  5  s^—  2  e"). 

Hence  we  find,  that  for  any  time  whatever  t,  this  term  is  represented  by, 

6  v''=       (0',820290  —  t .  0',000593)  .  sin.  (5  n't  — 2  n'" i  +  5  s^—  2  £'') 
—  (1 -,837963  +  t .  0^000015)  . cos.  (5  n'^t  —  2  rrt  +  5  e^—  2  s''). 

To  determine  the  part  of  the  great  inequality  of  Jupiter,  depending  on  the 
products  of  five  dimensions  of  the  excentricities  and  inclinations  of  the  orbits, 
we  have  computed,  by  the  formulas  [3860—3860'^],  the  values  of  iV*"',  N^^\ 
&c.  for  the  tAvo  epochs  1750  and  1950,  and  have  found. 


In  1750. 
a\iV('"=       0,00000135044 
fl\iVW=       0,00000789719 
a\  iV'='  =  —  0,0000198552 
a\iV(3)=       0,0000175127 
a-\  iVH)  =  —  0,0000066540 
a\  iV<^)  =       0,0000009277 
a\N^'^=       0,0000003618 
a\  iV<''  ^       0,0000003643 
a\  A^<«'  =  —  0,0000001720 
a\  iV'^'  =       0,0000000730. 


In  1950. 
a\  iV<°'  =       0,00000129983 
fl^7V(')=:3       0,00000754771 
a\  iV<"~)  =  —  0,0000196012 
«\iV'="=       0,0000172415 
a\  iV'"  =  —  0,0000066551 
a\  N'-'^  =       0,0000009408 
a\  N'-'^  =       0,0000003562 
a\  iV'"  =       0,0000003460 
«v,jV(S)  ^  —  0,0000001712 


[4426] 


14427] 


[4428] 


[4429] 


Terms  of 
the  fifth 
order  on 

e,  e',  7. 


[4430] 


a\  iVW 


0,0000000732. 


*  (2664)     The  term  [4426]  is  the  same  as  that  depending  on  — |/Je  [3844],  accenting 
the  symbols  as  in  [4402a] .     In  this  case  H   denotes  the  coefficient  of, 

73 


VOL.    III. 


[4431] 


290  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

By  means  of  these  values*  we  have  computed  the  corresponding  inequality  in 

[4430]     Saturn,  in  [4487].     Multiplying  it  by  the  factor     —~?~r-,    we  obtain  the 

following  inequality  of  Jupiter,t 

6 1,'"  =  _  (1 2',536393  —  t .  0^001 755)  .  sin.  (5  Ji'f  —  2  n'" i  +  5  £"  —  2  s") 
+   (8',120963  +  t .  0-,004885)  .  cos.(5  ift  —  2n'''t  +  5  £>—  2  s"). 

Lastly,  we  have  computed,  by  the  method  in  [4003],  that  part  of  the  great 

inequality  of  Saturn,  which  depends  on  the  square  of  the  disturbing  force, 

[4431]     ^j^ij   jj^    q£    ^    sensible    magnitude.      Then   we   have   deduced   from  it    the 

corresponding  inequality  of  Jupiter,  by  multiplying  it  by 177^  !     which 

gives,  for  this  last  inequality,  the  following  expression,^ 


[4426a]  COS.  {5n't—-3nt-\-5s'—3s-\-  A), 

in  the  expression  [3814],  corresponding  to  Jupiter.     Computing  the  value  of  — |  He",  for 
[44266]    jj^g  ygj^j.g  j^j5Q^  jggQ^  ^  jjj  [4427,4428],  we  obtain  its  annual  increment,  and  the  general 

value  [4429]. 

*  (2665)     The  signs  of  all  the  terms  in  [44-30,  4431],  are  different  in  the  original  work  ; 
[4430a]    ^^g   j-^^yg  clianged    them,    iii    order  to    correct    the    mistake    in  the    signs   mentioned  in 
[3860«]. 

t  (2666)  Changing,  in  [1208],  ,g,  <^',  into  iv",  ôv^,  which  represent,  respectively,  the 
corresponding  parts  of  the  great  inequalities  of  Jupiter  and  Saturn,  we  get,  by  using 
the  notation  of  [4402«], 

[44306]  5«-=_^'^.5v 

[4430c]    Substituting  in  this,  the  values  w",    m",     a'',    a^    r5  «"  [4077, 4079,4487],  we  get  [4431]. 


[4431o] 


X  (2667)     We  have  already  mentioned  in  [4006^ — 4007rt]  the  difficulties  which  occurred 

in  computing  this  part  of  the  great  inequality  of  Jupiter,  and  liave  also  observed,  that  the 

numbers  given  by  the  author,  in  [4432],  are  inaccurate  ;  the  chief  coefficient  having  a  wrong 

sign,  as  Mr.  Pontécoulant  found  by  computing  the  most  important  terms,  depending  on  the 

[44316]    arguments  contained  in  the  table  [4006m],  numbered  from   1  to  10,    and  from    1'    to   10'. 

The   parts  of  êv",  corresponding  to  these  terms,  are  given  in  [4431/],  from  the  abstract, 

printed  by  Mr.  Pontécoulant,  in  the  Connaissance  des  Terns,  for  1833  ;  using,  for  brevity,  the 

^^^^^'^     symbol    T5  =  5  ift  —  2  n'H  +  5  s'  —  2  i"  [3890J] .     The  first  line  of  the  function  [443 1/] 

[4431rf]    ig  produced  by  the  term    3  ci^ff.  {ndt.dll  ./d  7?)  [5844]  ;    the  other  lines  arise  from  the 

products  of  the  quantities  in  the  table  [4006m],  marked  with  the  numbers  on  the  same  lines 


Vl.xii.  ^^33.] 


THEORY  OF  JUPITER. 


(  ]%6U663  —  t .  0%00'l68S)  .  sm.  (5  n't  —  271'" t  -\-  5  e^  —  21''') 
—  (18',461954+  i.0',001515) .  cos.(5 if  t  — 2  n"t +  5  B''—2r). 


291 


[4432] 


respectively.  The  sum  of  all  these  terms  is  given  in  [4431^]  ;  and  it  differs  essentially  from 
that  of  La  Place,  in  [4432]  ;  particularly  in  the  term  depending  on  cos.  1\ ,  which  has  a 
difl^rent  sign,  though  it  is  nearly  of  t)ie  same  numerical  value  ;  an  error  in  the  sign  having 
been  discovered  in  the  original  minutes  of  the  numerical  calculation  of  La  Place. 

5  u"  =  +  0',02489  .  sin.  T,,  -f-  0',002G6  .  cos.  T5 

1  +  0',08628  .  sin.  Tj  —  0%01857  .  cos.  T5 
1'  —  2',00454  .  sin.  T^  +  0%4375-  .  cos.  T^ 

2  +  0',07587  .  sin.  T5  +  (y.OSlQT  .  cos.  T^ 
2'  +  0',39242  .  sin.  Tr,  +  0,22555  .  cos.  7^ 

3  +  0%28829  .  sin.  T5  +  0',19273  .  cos.  T5 
3'  —  0%71831  .  sin.  7^  —  r,5S65S  .  cos.  T^ 

4  _  0',14619  .  sin.  Tg  —  0^09422  .  cos.  Tg 

5  —  0%76290  .  sin.  T5  +  0',-7529  .  cos.  Tj 

6,  6'  +  2%16304  .  sin.  T5  +16',97139  .  cos.  T^ 

7,  i  =  2,  +  6',G2968  .  sin.  T5  —  0%80829  .  cos.  Tg 

7,  t  ==  1 ,  —  2,49438  .  sin.  T5  —  0,92192  .  cos.  Tg 

8,  i  =  2,  +  0',22613  .  sin.  Tg  —  0^53472  .  cos.  Tg 

=       3',76028  .  sin.  Tg  +14'',72286.  cos.  ïg . 

In  computing  these  numbers,  the  mass  of  Saturn  is  supposed  to  be,  as  in  [4061  J],  equal  to 
WbT^  ■>  instead  of  t^tî^jï)  used  by  I^a  Place  [4061].  To  compare  them  with  La  Place's 
calculation  [4432],  given  below,  in  [4431it],  we  must  increase  the  coefficients  [4431^],  in 
the  ratio  of  3512  to  3359,4  ;  by  which  means  they  will  become  as  in  [4431iJ  ;  the  terms 
depending  on    t,    t^,    being  neglected  ; 

5  V"  =  3',93109  .  sin.  Tg  +  15',39164  .  cos.  Tg  ; 

ôv"=  p-,64166  .  sin.  7'g—  18',46195  .  cos.  Tg . 

The  difl'erence  of  the  two  expressions  [443h', ^],  which  we  shall  denote  by  C'",  is  a 
correction,  to  be  applied  to  the  formula  [4433  or  4434]  ;  and  we  shall  have, 

C  =3  2',2S943  .  sin.  Tg  +  3.3',85359  .  cos.  Tg. 

We  may  remark,  that  the  number  of  terms  of  the  forms  7  to  10,  and  7'  to  10',  [4006m], 
is  infinite  ;  but  it  is  only  necessary  to  notice  a  few  of  them,  in  which  S  r,  5  v,  â  r',  or  ô  v', 
have  sensible  values.  Moreover,  the  terms  depending  on  ô  i,  were  not  computed  by  Mr. 
Pontécoulant,when  he  published  the  above  results.  The  effects  of  the  correction  C"  [4431/], 
of  the  terms  depending  on  S  s,  and  of  other  quantities  of  a  similar  nature,  are  taken  into 
consideration  in  book  x.  chap.  viii.  [9037,  &ic.]  ;  where  the  final  results  of  all  these 
calculations,  relative  to  the  inequalities  of  the  motions  of  Jupiter  and  Saturn,  are  given. 


[4431e] 


Terms  of 
the  order 
of  the 
square  of 
the  dia~ 
tuibin^ 
forces. 


[4431/] 


[443%] 


[4431A] 


[4431  i] 
[443U] 

CorrectioH 
of  ihe 
g:reat  ine- 
quality. 

[4431J] 
[4431m] 
[4431n] 
[4431o] 
[4431;?] 
[4431g] 


292  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

Now,  if  we  connect  the  several  parts  of  the  great  inequality  of  Jupiter,  we 
shall  obtain,  for  its  complete  value,* 

r  (126P,569155— ^0',013495— /3.0',0000I9247).sin.(5w^<— 2n'-i'+5£^— 2si')- 
[4433]       (1+1^^).)+  (9G',466088— t0%474651+^2.0.00007S564).cos.(5«^<— 2«'7+5e>— 2£'^)J 
C+  function    C"  [4431/]  -}- 2  5  v'"  [4431] 

If  we  reduce  these  to  one  single  term,  by  the  method  in  [4024 — 4027"],  we 
«'"'",.       shall  obtain,  for    5  v",  the  following  expression, 

inequality.  '  '  o  1  ' 

\(1265',251781-<.0',037090+i-0',000036669).sin.  ]/ 

[4434]       (l+,^^)-r  '  '  T  J       V-<.77»-,653  +  r2.0',013581      A. 

(+  function    C'"  [4431/] +2.5 î;'"  [4431]  ) 

This  inequality  may  require  some  correction,  on  account  of  the  coefficient  i^", 
depending  on  the  value  of  the  mass  of  Saturn  ;  and  also  on  account  of  the 
[4434]  slight  imperfection  in  the  assumed  value  of  the  divisor  (on' — 2n)^;  a  long 
series  of  observations  will  remove  this  small  source  of  error.  We  must  apply 
this  great  inequality  to  Jupiter'' s  mean  motion,  as  we  have  seen  in  [4006"]. 

The  square  of  the  disturbing  force   produces  also,  in   6  v'",    the  inequality 
[3890], 

[4435]  (5 1)''  = ^  .  ^ .  sm.  (double  argument  oi  the  great  inequality)  ; 

which,  in  numbers,  is, 

[4436]  &v"  =  —  13",238897  .sin.  (double  argument  of  the  great  inequality)  ; 

ive  must  also  apply  the  inequality  of  a  long  period  to  the  mean  motion  of 
Jupiter. 

The  inequality  [3921], 

[4437]     6v-=  1 .  ^•^"'"^""+^^^^"^^ffJr.sin.(5>r/-10»-/  +  53'--10s--i?-2), 

reduced  to  numbers,  becomes, 
[4438]  6  If"  =  _  4',024751  .  sin.  (5  n'"  t  —10  n-t  +  5  £"—10  s^'  +  51"  21'"  .55'). 


[4433a] 


*  (2668)  The  expression  [4433],  is  the  sum  of  the  terms  contained  in  the  functions 
[4418,4425,4429,4431,4432]  multiplied  by  (1+  l^''')-  Then,  by  computing  this  expression 
for  the  times,  t  =  500,  and  t  =  1000,  we  may  reduce  the  whole  to  one  term,  as  in 
[4434],  by  the  method  explained  in  [4024—4027"]. 


VI.xii.>^33.]  THEORY  OF  JUPITER.  293 

We  have  also,  in  [3844],  the  inequality,* 

6  v'"  =  ^  .  Ke'\  sin.  {5  n't —  4>  n'" t  +  5  i"  —  4>  s"  +  z^'"  -J^  B)  ;  [4439] 

and  by  reducing  it  to  numbers,  it  becomes, 

&v"  =  10',084660.sin.(4n'^i:  — 5n^-^  +  4s'^  —  5 £^  +  45''21"'440  ;  [4440] 

if  we  connect  this  Avith  the  two  inequalities  [4392], f 

P,097613  .  sin.  (5n'i— 4?i'^'/ +  5  s"— 4  s"  —  z^") 
—  2',781664.sin.  (5 n't  —  4> n'" t -^  5 1"  —  4> s"  —  z^" )  ; 

we  obtain  the  single  equivalent  expression, 

6v"  =  (l  +  t^")  .1  P,506 190  .  sin.  (4  n'"  t  —  5  n"  t  +  4>  s"—  5  6"+  OS'' 00™ 36^).      [4442] 

We  have  seen,  in  [3773],  that  the  expression  of    d.iv'"  contains  a  secular 
inequality,  depending  on  the  equation, 


[4441] 


[4439a] 


*  (2669)  The  inequality  [4439],  is  the  same  as  the  last  of  [3344],  augmenting  the 
accents  of  e,  n,  n',  Sic.  to  conform  to  the  present  example.  The  term  K,  which  occurs 
intliis  expression  is,  by  [3824 — 3826],  equal  to  the  constant  term  of  the  coefficient  of  the 
part  of  [4394].  depending  on  the  angle  3  n'^t  —  5  ?i''  t  ;  or  rather  on  the  angle  ôtVt — 3n"'t. 
This  part  being  nearly  equal  to 

—  1 69^265895  .  sin.  (5  n"  t  —  3 n'^'t  +  5 1"—  3  s'^—  55''40"' 49^.  [44394] 

If  we  compare  this  with  [3826],  putting    i=5,   we  get, 

Z  =  — 169%265895;  i?  =  —  55M0™  49"' ;  [4439c] 

and  by  [4081],   ra"'=  10''  21'"  4'  ;  hence, 

•TO"-  -\-B=—45''l  9'"  4.5^  ;  [4439(/] 

and  [4439]  becomes, 

^.Ke'\sm.{5n't  —  4  71'"  t -{- 5  b"  —  4  e'" —45'' 19™ 45') 
=  —  f .  Z  é\  sin.  (4  n'^t  —  5  n"  t  -\- A  t"—  5  s"  +  45"  19"  45"). 

Substituting  in  this,  the  value  of   K  [4439c],  and  that  of    c"   [4080],  it  becomes  neai'ly  as 
in  [4440]. 

t  (2670)     These   mequalities  are  found  in  the  ninth  and  tenth  lines  of  [4392],  with  a 
slight  and  unimportant  variation    in   the   first  coefficient.      These   terms    [4441]  may  be     [4440a] 
connected  with  [4440],  and  reduced  to  one  term,  of  the  form  [4442],  by  the  method  given 
in  [4282A— Z]. 

VOL.  III.  74 


[4439e] 


294  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

d.dv'"  m".»'^ 


dt  8 


Hence  we  deduce,* 

[4444]        ^^"'=  —  23%9441  .  e''=^—  27%7951  .  e'=^  +  42^,9296  .  é\  e\  cos.  (^-—  ^"). 

[4444']      ^^  ''^^^Z  neglect  the  constant  part  of  the  second  member  of  this  equation, 
which  is  confounded  ivith  the  mean  motion  of  Jupiter,  and  then  we  shall  have,t 


*  (2671)      We  have,  as  in  [.3756a,  è], 

2  2  2  2  2  2 

[4443a]  h'"   +  l'"  =  e"'  ,      A"  -j-  P  =  e"  ,       li"  h"  +  t'  />'  =  e'"  e" .  cos.  (to^—  to'' ). 

Substituting  these  in  [444-3]  ;  also  the  values  of  .^"",  A'-^\  and  their  differentials,  in 
terms  of  Oj,  and  its  differentials  [996 — 1001];  then  the  values  of  these  quantities 
[4202,  Sic]  ;  we  finally  get  the  expression  [4444] . 

f  (2672)  We  shall  put  E  for  the  general  expression  of  the  second  member  of  [4444], 
corresponding  to  any  value  whatever  of  t,  and  E  for  its  value  when  ^  ^  0  ;  then  substituting 
the  values  é",    e",    -a'",    -n'  [4407],  we  shall  obtain, 

[4445a]  ^-#-'  =  ^  =  E  +  ^-^+^°-     [4444,4445a]. 

Multiplying  this  by  d  t,  and  integrating,  supposing  Sv'"  =  0  when  t  =  0,  we  get, 
[44456]  6v^''=  Et  +  ^.  —  .t^  +  kxi. 

of  which  the  first  term   Et,   may  be  neglected,  being  confounded  with  the  mean  motion  of 
Jupiter  ;  then  we  have,  by  neglecting    t^,    t'^,    &c. 

s    iv         1     ''^     v2  d.Sv'"        dE  .     ^....-. 

[4445c]  èv'^  =  i.-.f,      or      --^  =  —  .t,     as  m  [4445]. 

The  coefficient  of  t,  in  the  second  member  of  this  last  expression,  represents  the  differential 

of  the  second  member  of  [4444] ,  divided  by   d  t,  corresponding  to  the  time  of  the  epoch 

1750.     Substituting  in  it  the  values  [4405],  and  dividing  by  the  radius  in  seconds  206265^, 

we  get, 

d.Sv'v 
[4445d]  —7^  =  —  0',0000013 .  i,     nearly. 

This  equation  being  multiplied  by  d  t,  and  integrated,  gives  [4446]  ;  no  constant  quantity 
being  added,  because  it  is  supposed  to  vanish  when   t  =  0. 


VI.xii.<^33.]  THEORY  OF  JUPITER.  295 


il^^  _  03-=  9441  .t.2  e'\  —  —  27^7951  .  < .  2  e".  ^ 
dt  (It  dt 


[4445] 


+  42^9296.ï.5(e-.  ^  +c\  ^).cos.(ra-— ^"O— e'^e^'^^^ ^'.sin.(«^— ^»)^. 

Substituting  for     ^  ,    '-^,    ^"^    '-^\     their  values,  given  in  [4405],  and 

integrating,  we  obtain, 

^v'-  =—t~.  0',00000065.  [4446] 

This  inequality  is  insensible  in  the  interval  of  ten  or  tivehe  hundred  years, 

and  even  as  it  respects  the  most  ancient  observations  that  have  been  handed     [4446'] 

down  to  us  ;  therefore  we  may  neglect  it. 

It  now  remains  to  consider  the  radius  vector  of  Jupiter.  We  have  found, 
in  [3845],  that  the  terms  depending  on  the  powers  and  products  of  the 
third  degree  of  the  excentricities,  add,  to  the  expression  of  this  radius,  the 
quantity,* 

i ,--  =  —  H  a'\  é\  COS.  (5  n"  ^  —  2  n'''  i  +  5  s'  —  2  è^—  ^''+  A) 

+  Hà\  é\  COS.  (4  «'''i  —  5  n" Ï  +  4 a-—  5  s'  —  ^'"—A)  ^^447] 

^  Correc- 

,4m\n-.a-2r       p  .sin.  (5  w'i  — 2  7ii^<+5a'— 2  6-)  )  'A°dius'"" 

-\ .  <  ■   >  r  •  vector. 

5,iv_2„.v    ^_[_p'.cos.  (Sn^i— 2n'''<+5  6''— 2s"')!) 
Reducing  this  function  to  numbers,  we  obtain, 

(— 0,0003042733. cos.(5n'i—2n"'^+5s'— 2s'''— 12''08'"490) 
6r'^=(l  +  f^').<  >•      [4448] 

(  + 0,0001001 860. cos.(4/î''i—5?i'ï+4si'— 5s' +  45n6"'470  ^ 

If  we  connect  this  expression  with  the  terms  computed  in  [4393], 

i,_  J       0,0000268383. cos.(5n'<  —  4w"'i  +  5E'—4ê''—ra''')? 

àr  —{^       '^^'l  — 0,0000516048.  cos.(5r^  —  4n'7  +  5s'  — 45'"-^')^'         ^'^'^^^^ 


*  (267.3)    The  expression  [4447]  is  composed  of  the  three  last  terms  of  [3845],  increasing 
the  accents  as  in  [4383a].     The  value  of  H  is  as  in  [4426a]  ;    those  of  P,    P',  as  in 
[4402]  ;  the  other  elements  are  given  in  [4061,  4077,  4079,4080]  ;    hence  the  expression     [4447a] 
[4447]  becomes  as  in    [4448].      Connecting  this  with  the  two  terms  of    or",    given  in 
[4393  or  4449],  and  reducing  by  the  method  [4282A— Z],  we  obtain  [4450]. 


296  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

we  obtain  the  following  result, 

[4450]     à  r"=  (1  +  f^O  •  0,0000983161  .  cos.  (4  n'^t  —  5  n't +  4,  £'^—  5  s-—  14''23'"  19'). 

The  semi-major  axis  a'",  which  we  have  used  in  calculating  the  elliptical  part 
[4450]     of  the  radius   vector,  must  be  augmented  by  the  quantity    ^o'".  m'"  [4058]. 
Adding  this  to  the  expression  of    a'"  [4079],  we  obtain, 

[4451]  a'"  =  5,20279108. 

Inequalities  of  Jupiterh  motion  in  latitude. 


34.  It  follows,  from  [3931,3931'],  that  the  terms  depending  on  the 
square  of  the  disturbing  force,  add  to  the  values  of  — -  ,  — — ,  the  following 
quantities,* 

*  (2674)     In  deducing  the  differentials  of    5  9,     5  è,   Uc.  from  [.3931—3932'],  in  order 

[4452a]    jQ  f5|^(i  jjjg  increments  to  be  applied  to  the  values  of     -tt^    "tt")  ^c.   [4246,  &tc.],  we  may 

consider  5y,  0  II,  J  <p,  5  ë,  to  be  the  only  variable  quantities  ;  or,  in  other  words,  we  may 
neglect  the  variations  of  n,  è,  ç,  y,  on  account  of  their  smallness.  For  the  expressions 
of    5  7,    i5  n  [393.5,3936],  which  are  independent  of  the  periodical  angles,  are  of  the  order 

[4452!)]    m'~;    consequently  their  differential  coefficients     -77")  ,    are  of  the  ««me  order,  and 

are  therefore  much  greater  than  the  terms  arising  from  the  variations  of  the  angles  n  —  ê, 
in  the  differentials  of  the  expressions  [3931 — 3932']  ;  because  these  last  terms  depend  on  the 

[4452c]     products    ^7-jt^    ^'^'Jt'    ^c.  which  are  evidently  of  the  order  m'^  ;   since     -^,      -— , 

[4411]  are  of  the  order  m'.  Hence  the  differentials  of  [3931,3931']  become,  by  dividing 
by    fl  t,   and  increasing  the  accents,  as  in  [4388o]  ; 

*    —- : -^ ^  .]—r-^   .cos.  (n  —  è") — y.—, —  .sm.fn  —  ô'")}  ; 


[4452e] 

[4452/] 


dt 


p. — ; —  = : — -— ^ —    .  } '-  .  sm.  (n  —  ô'>)  +  7.— --•  .cos.fn  —  Ô"-)}. 

^       dt  j«'^  y/a"' + '"'Va"      i    dt  ^  '    ^    '       dt  ^  '5 

Now,  from  [4410],  we  have. 


[4452g]  1^  =  O',000184  =  ^  ;  ^'  =  _  0^00T631  =  '^  ; 

substitutmg  these,  in  [4452e,/ J,  we  get,     — — — ,      — — -  ,    which  are  changed  mto     -j-, 

U    Z  (I-    t  lit 

[4452;»]    1^",  in  [4452,4453];  and  by  using  [44-52^],  also  the  values  of  y,    n  [4409],    m'\    m\ 


VI.xU.§34.]  THEORY  OF  JUPITER.  297 


^'=  — 0%078213 

dt 


—  0',223251 
dt 

de" 

—  =       6',457092 
dt  ' 

dt 


Then  we  find,  by  means  of  the  formula  [42956] 


[4452] 


dt  ~  ;H''Va"-fm''.v/«''   l^  '  t  ^  ) 

^  =  -     -"'-^"" .$i2'.sm.(n_r)  +  ,.i^.cos.(n-r)^-  [4453] 

6 J,     en,    beuig  comiKited  by  the  formulas  [3931,3931'].     Reduchig  these 
functions  to  numbers,  we  obtain, 

ifL  =_0',000073;  [4454] 

dt 

^=       0,000811.  -  [4*5^1 

dt 

d(f"'         d(f>y 
The  first  of  these  expressions  must  be  added  to  the  values  ot       — ,       -j^ 

[4246],  and  the  second  to  the  values  of    -j^,      '-^      [4246]  ;    hence  we 
obtain, 

dtpi 


[4456] 


a'",    a",    ê"  [4061,4079,4083],  they  become  as  in  [4454,4455].     Adding  the  expression 

[4454]  to  the  first  terms  of    -—    and    -y-      [4246],   we  get  their  values  [4456]  ;    also     [445ai] 

do"  rfd'" 

addmg    [4455]    to    the    first   terms    of      — —      and       -~      [4246],    we    obtain    the 

correspondmg  values   [4456]. 

*  (2675)     Tlie  terms  of    us'"'    [4457],  are  deduced  from  those  in   [4295&],  by  adding 

three  accents  to  the  symbols    m",    n',    n",    /,    î",    a',    a",    in  order  to  conform  to  the  case    ,..._, 
•'  )       J        J       3       ;       :        3  r4457nl 

now  under  consideration.     7,    IT,    are  as  in  [4409].     The  values  of    5<'~'^=  —  .  0  „ 
[1006],  are  given  in  [4210,4079]. 
VOL.  III.  75 


298  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

/      0  ,564458  .sin.  (n"  ^  +  s"  —  rr) 
\  +  0',663927 .  sin.  (2  fi't  —  n'"t  +  2  s"  —  s-  —  n'") 
[4457]       6  5'"=  (1  +^^).|-j-  V,\l97S2.sm.(3n''t  — 2 n"t  + 3s-— 2 ^^  —  n-")^^; 

—  0',279382 .  sin.  (4  n't  —  3  n'H  +  4  s' —  3  .'^  —  n'^) 

—  0',269130  .  sin.  (2  n'-t  —  ift  +  2  s''  — s'— n'^) 

n'',    in  this  formula,  being  the  longitude  of  the  ascending  node  of  Saturn's 
[4457']     Q^}j{t  iipon  that  of  Jupiter   [42956 — c].      Lastly,  we  have,  in   [3885],  the 
inequality,* 

[4458]  6  s'"  =  3',941 680 .  sin.  (3  n'^t  —  5  Ji' ^  +  3  i"  —  5  s''  +  59'-'  30»  35'). 


Inequali- 
ties ill  the 
latitude. 


*  (2676)     The  quantity  [4458],  is  deduced  from  [3885],  reducing  both  terms  to  one,  as 

[4458a]    in|-4282A-/]. 

Before  concluding  the  notes  on  this  chapter,  we  may  remark,  that  the  inequalities  of  the 
motions  of  Jupiter  and  Saturn,  computed  in  tliis  book,  are  corrected  by  the  author  in 
[5974,&ic.],  and  afterwards  more  thoroughly,  in  book  x.  chap.  viii.  [9037,&ic.]  ;  where  he  has 
decreased  the  assumed  value  of  the  mass  of  Saturn  [4061].      He  has  also  computed  several 

[4458  ]  ^^^jj  inequalities,  which  had  not  been  previously  noticed,  and  has  given  new  forms  to  some  of 
the  arguments.  Finally,  the  subject  of  these  inequalities  has  been  treated  in  a  wholly  different 
manner,  withafrequentuseof  definite  integrals,  by  Professor  Hansen,  Director  of  the  Observatory 
.  g  ,  at  Seeberg,  in  a  memoir,  entitled,  "  Untersuchung  ueber  die  gegenseitigen  Storungen  des 
Jiipiters  und  Saturnsf  which  gained,  in  1830,  the  prize  of  the  Royal  Academy  of  Sciences, 
of  Berlin,  relative  to  the  inequalities  of  these  two  planets.  In  this  method,  the  true  longitude 
is  computed  by  means  of  the  elements  corresponding  to  the  invariable  ellipsis  at  the  time  of  the 

[4458rf]    epoch  ;  taking  instead  of  t,  a  function  of  t,  which  corrects  for  the  perturbations.      As  the 
inequalities  of  Jupiter's  motion  had  not  been  completed  by  Professor  Hansen,   when  he 

[4458c]     published  this  memoir,   we  may  have  occasion  to  refer  to  it  more  particularly,  after  the 
completion  of  his  work. 


Vl.xiii.  §35.] 


THEORY  OF  SATURN 


299 


CHAPTER   XIII. 


THEORY  OF  SATURN. 


35.     The  equation  [4386], 

r 
corresponding  to  Jupiter,  becomes  for  Saturn, 

If  we  take  for    r",   and    r\    the  mean  distances  of  the  earth  and  Saturn  from 
the  sun  [4079],  and  suppose     6  V' =  ±  1"  =  ±  0',324,     we  shall  find, 

6?-  =  ±0,000141326. 
Therefore  we  may  neglect  the  inequalities  of     àr",     below     =F  0,000141. 
We  shall  also  neglect  the  inequalities  of  Saturn,  in  longitude  and  latitude, 
which  are  less  than  a  quarter  of  a  centesimal  second,  or  0%081* 

Inequalities  of  Saturn,  independent  of  the  excentricilies* 

,+  3%156532.sin.    (w''i  —  n"i  +  s'"  — £ 
— 3r,493729  .  sin.  2(«"i  —  71" t  +  i'"  —  =' 

—  6',56593 \  .  ûn.S{n"' t  —  n' t  +  b"  —  i 
-  1%965748  .  sin.  4(/i'''i  —  n^t  +  i"  —  î 

ii)'==(l  + (.'').  ^  _  0',697047  .  sin.  5(n'^^  — n^i  +  £"  — s' 

—  0,270789  .  sin.  6 {n}" t  —  n't-\-  s'''  —  s 

—  0-,  1 1 6291  .  sin.  7  (ir  t  —  n't  +  £*'  —  s 

—  0',056126  .  sin.  8(n"'t  —  nH  +  i"  —  s" 
K—  0%034097  .  sin.  9  (n'^i  —  n't  +  s'"  —  =" 


[4459] 


[4460] 


[4461] 

Terms 
which 
may  be 

neglected. 

[4462] 


Inequali- 
ties inde- 
pendent of 
the  ex- 
cent  rioi- 
ties. 


[4463] 


*  (2677)     These  are  computed  as  in  [4277a — 0],  increasing  the  accents  on  a,  n,  rt,  hx,. 
so  as  to  conform  to  the  present  case. 


[4463a] 


300 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4463] 


+  (l+f^^') 


InequftTi- 
ties  inde- 
pendent of 
the  excen- 
tficities. 


ir'=(l+f^") 


[4464] 


+  (l+f^'') 


+  9',248269  .  sin.  (n^H  —n't  +  i"'  —  s^) 
—14^451913  .  sin.  2(ri'H  —  n''t  +  s-  —  s") 

—  l',427160  .  sin.  3(»'"  t  —  n''t  +  s"'  —  s^) 

—  0  ,314960  .  sin.  A^Çn^'t  —  n"  t -{- b"' —  s") 

—  0',090690  .  sin.  5  (n^'t  —  n"  t  +  s^ 

—  0%047444  .  sin.  6  (n"'  t  —  n't  +  t" 

—  0',010686  .  sin.  7(/j''7  —  n't  +  i" 

—  0%003942  .  sin.  S  (if 't— n't  +  i" 


'  +  0,0039077763 
+  0,0081638400.  cos.  (n''i  —  rC  /  +  e'^—  ^\ 
+  0,0013838330.  cos.  2  {n"t  —  TCt-\-  e'^—  e' 

1  +  0,0003200673  .  cos.  3  {iVt  —  n't  +  £'"—  £^ 

'+ 0,0000992632.  COS.  4  (n''ï  —  n"ï  +  £'"  —  £^' 
+  0,0000355919.  COS.  5  (m'"^  —  m^ï  +  e'^—£^ 

I  +  0,0000135999  .COS.  6  (w'^/  —  «"^  +  f'^  —  £' 
+  0,0000(  f55 1 35  .  COS.  7  {n'"  t  —  ')ft+  e'"  —  £\ 
+  0,0000021631  .COS.  8(?r^  — Jt^^  +  E'"— e" 
+  0,0000006436 .  cos.  9 (n" t—7ft-^  e"_  = 

'—0,0000137622 
+  0,0001491217. cos.  (71"  t  —  7^  t  +  i"  —  i''' 

-  0,00039499 1 6 .  cos.  2  (n'  f  —  »r'  i  +  £"  —  e' 

'  —  0,0000480303 .  cos.  3  {7f  1  —  7^1+^''—  e' ' 

-  0,00001 1 8201 .  cos.  4 («^  Ï  —  n^  7 +  £"— £"' 

—  0,0000036280 .  cos.  5  {if  t  —  »"  t  +  s^—  e^ 

—  0,0000012501 .  cos.  6  {7ft  —  n'H  +  e^  —  s^ 


Inequalities  dependiTig  07i  the  first  poiver  of  the  excentricities* 

We  shall  here  notice  the  secular  variations  in  the  coefficients  of  those 
[4465]      inequalities  of  Saturn,  Avhich  exceed  1 00",  or  32',4  ;  in  the  same  manner 
as  we  have  done  for  Jupiter,  in  [4389'].     Hence  we  have, 


[4466a] 


*  (2678)      The    inequalities  depending    on  tlie  first  power  of   the  excentricities,    are 


computed  in  the  same  manner  as  for  Jupiter  [4390a,  &c.]. 


VI.xiii.§35.] 


THEORY  OF  SATURN. 


301 


èv"^  (l  +  f^'"). 


+  (l+f^'") 


— ir,509517  .  sin.  (trt  +  i'  —  z^) 
+    r,258041  .  sin.  (rrt  +  s'"  —  tz'") 

—  2'-,064438  .  sin.  (2  n'7  —     n't  -\-2  i"—     s-  —  a" 
+   2^,672881  .  sin.  (2  7rt  —     «"i  +  2  e"—    s"  —  ^i' 

—  0^292291  .  sin.  (3  n"t  —  27ft  +3  s"—  2  ='  —  in^ 

—  0',223191  .  sin.  (3  »"<  _  2  ?i'^  +  3  s"—  2  6"—  ^' 

—  0%090633  .  sin.  (4  7rt  —  3  n^i  +  4  s'^—  3 1"  —  .3* 

— (1 82%068686  — Ï.  0S0101095) .  shi/_^^^^J^^l, 
+  (41 7',057741  + 1 .  0^0]  38572).  sin.  (_^Z^_~.!!^l;}j 


+   (34',341627  — ^0^0019068).sin. 


Sn''t  —  27i"t 

_^3sV_2çiv_-,v 


VOL.   III. 


— 17'-,654164  .  sin.  (3  n^i  — 2  ?»"< +  3  s"  — 2a"  — ^^'^ 
+  4',795080  .  sin.  (4  «"i  —  3  ?^'^i  +  4  s'  —  3  s'"  —  k'' 
■  2%43541 0  .  sin.  (4  rt''  i  —  3  n'"  i  +  4  s"  —  3  s"  —  ^'^ 
+    r,393612  .  sin.  (5  7ft—^n"t  +  5  £"—4  s'^'—z^^ 

—  0-,703450  .  sin.  (5  ift  —  4  n'H  +  5  s^—  4  s''  —  ra'" 
+    0S537161  .  sin.  (6  71" t  —  5  n'" t  J^  6  s"  —  5  s'"  —  z>' 

—  0-,25651 0  .  sin.  (6  'ïû'  t  —  5  n'"  i  +  6  a"  —  5  s'"  —  ^'^ 
+    0V2]  6195  .  sin.  (7  n't  —  6  n'^  t+l^'  —  Q  s'^  —  ^^ 

—  0',  1 07342  .  sin.  {l7i't  —  &  ir t  +  1 1'—G  s'"  —  -sj" 

,+    l',142398  .  sin.  (7tH  +  a"  —  tn^) 

—  P,01 1647  .  sin.  {ifH  +  s^^  _  ^") 
—10^033866  .  sin.  (2  n" t  —  7i''t  +  2  s"'  —  s^  —  z,^  ) 
+    2%766173  .  sin.  (2  >t^7  —  Ji'i  +  2  s^'  —  s''  —  t^^i-^ 

-16^936280  .  sin.  (3  71'' t  —  2  7^1  +  3  s"'  _  2  5'—  :3^ 

+  25',  153348  .  sin.  (3  w^'i  —  2  n^i+  3  s"  —  2  «'— «" 

+    0',559336  .  sin.  (4  rf't  —  3  n"^  +  4  h"'  —  3  s'  —  ^^ 

'  —  0',758225  .  sin.  (4  n^'t  —  3  7ft -^4,  s"'  —  3  £"—  ^3^' 

—  0-,  1 87729  .  sin.  (5  n'H  —  4  n^' ^  +  5  s''  —  4  s'  — 

—  0',673817.  sin.  (2n^i—  «^■74-2?'—  «''— 
+  r,521577  .sin.  (3?i^^  — 2?i'''^  +  3s^  —  2e'"— 
+   0^  151 701  .sin.  (4?r^  — 3  «"'^ +  4«*  — 3  £"— 

76 


Inequali- 
ties de- 
pending on 
Ihe  first 
power  of 
iheexcen- 
tricities- 


[4466] 


302  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

/—  0,0003422170  .  cos.  (n'i  +  £^  — ^n'") 

I  —  0,0020775935  .  cos.  (2  ?ft~  n'H  +  2 s"—  e-_  w"  ) 

.     /I,     i„s    )+ 0,0053861750.  COS.  r2?rï  — n'7  + 2  s^—s"—^") 
(5r  ==(  1+  fji'^).  /  \  i  / 

j+0,0011594872.cos.  (3n^i  — 2n'7  4-3E''— 2.'"— ^'')j 
[4467]  j  —0,0006217670  .  cos.  (3  n^  i  —  2  n'^i  +  35"  — 2  £'"— ra'^) 

\+  0,00021 17893  .  cos.  (4  7iU  —  3  n'H  +  45"— 3  s"— ^^^  ) , 

+  n+  -)  ^— 0,0003750767.  cos.  (3  r'i  — 2  ?i'ï  +  3£^'— 2  s^—^^)> 
(+ 0,0005605490.  COS.  (3  n'V  —  2 H-' i  +  3  s^'— 2e'' —  ^")  ^  * 

Inequalities  depending  on  the  squares  and  products  of  the  excentricities  and 

inclinations  of  the  orbits* 

i"'n°';-  /       /k;,.  o  '.noon      ,  n.  rvno^oN     •     /3  n^t  —  n'" t  +  3  s" —  s'' 

^nS'"  /  -(54^847829_^.0^00362).sln.f      84^36"'45^-^.34',55 

order.  1  ^   '  ' 

^_  i     )+  28',526709.sin.(«'''ï  — n''^  +  E'''-£^  +  84''16'"430 

'-(669%682372-i.0%015469).sin.^-_j"5'g,j5!!5f_^^_4g.r5 
,,,^^,  ,  —    2-,935793.siii.(5n'^  — 3«"Ï+5e^— 33-— 57''O9'"O80 

[4468]  >  '  V 

(  +    1  •■,923552  .  sin.  (3  n^'t  —  Sn't  +  S  s"  —  3  s^— 67" 54'"43')  ) 
^^  ^    ^4-3^,025379.  sin.  (3  n"<—    n"^  +  3£''—    s'— 85''34'"120  ) 

If  we  connect  the  inequalities  depending  on     n'^t  —  n^t;     also  those    on 
[4468']     Sn^'t  —  Sn^t,     with  the  corresponding  terms  which  are  independent  of  the 
excentricities  [4463],  we  shall  obtain  for  their  sum,  the  following  expression, 


[4469] 


[4470] 


6r^=  +  (1  +  ij.'^)  .  28',967123  .  sin.  (n'U  —  n't  +  s'"— g^-f  78''03'"130 

—  (1  +  f^'O  .    1 ',9 16292  .  sin. (3  n^'  t  —  Qn-'t  +  S  s"—  3  ï>+68''27'"07'). 

Then  we  have,t 

'—0,0011710805. cos.  (3  n^ï  —  n'''^-f3i^  —  £''—90''I2'"350 
^,.v^(-l^^iv-j  1-0,0005621 901.  COS.  (    n'H  —  n't+    £i''_sv_83''26'"330  (. 
+(0,0151990624- 1 . 0,0000003370)  .cos.  (^"5J.;^^:'3;3+^^/'^^^ 


[4468o]         *  (2679)     Computed  as  in  [4394«,  Sic],  for  Jupiter. 
[4470(1]         t  (2680)     Tliis  computation  is  made  as  in  [4394c/] . 


VI.xiii.§35.]  THEORY  OF  SATURN.  303 

The  inequality  of  the  radius  vector,  depending  on  the  angle      li'^t  —  rft, 

being  connected  with  the  similar  term  in  [4464],  which  is  independent  of  the     ^       ^ 

excentricities,  becomes, 

f^r"  ^  (l  +  i^'O  .  0,0081090035.cos.(/r^  — n'^i  +  s-— e"— 3''57™35').  [4471] 

Since    5  n" — 2  n"    is  very  small,  we  have  computed  the  inequality  depending 

on  2»'''^  —  ^n't,    by  the  formulas  [3714,  3715].     Moreover,  as    Sn^'  —  n" 

is  very  small,  we   have  computed   the  inequality  depending  on  the  angle      [-44721 

on^'t  —  M'7,     by  the  formulas    [3711,3718].      For  greater  accuracy,    ive 

must  apply  this  last  inequality  to  the  mean  motion  of  Saturn,  on  account  of  the 

length  of  its  period. 

Inequalities  depending  on  the  poicers  and  products  of  three  and  Jive 

dimensions  of  the  excentricities  and  inclinations  of  the  orbits, 

and  on  the  square  of  the  disturhing  force. 

The  most  considerable  part  of  the  great  inequality  of  Saturn,  is  that  which 
has    (5  n'  —  2  n")',  for  a  divisor,  and  depends  on  P,  and  P'.     It  is  derived     [4472] 

from  the  great  inequality  of  Jupiter,  by  multiplying  it  by    —        v  '  wa'  iv?  "^      [4473] 

conformity  with  the  formulas  [3844,3846].*      Hence  we  get,  for  this  part  of 
the  inequality  of  Saturn,  the  following  expression, 

è  v'=  —  i 2957^357566  —  t .  0',01 9701  —  A  0^00004505 1 .  sin.(5  nU—2  n"t4-5  e^— 2 s") 

'  [44741 

—  |279%746590— / .  P,1086.38  +  î!2.0',00018387|.cos.(5w"<— 2m"Y+5ev_26'^). 


*  (2681)     If  we  represent,  for  brevity,  the  terms  between  the  braces  in  the  two  first 
lines  of  [3844],  by    aP^,    we  shall  find,  by  inspection,  that  the  two  fii-st  lines  of  [3846], 
between  the  braces,  are  equal  to  a'  Pg  ;    and  by  noticing  only  those  terms  of  5  r,  ô  v,  which    [4472a] 
have  the  small  divisor   (5  n' —  2  n)^,  we  shall  get,  by  increasing  the  accents  so  as  to  confonTi 
to  the  case  now  under  consideration, 

,    .  6jn».n''2  15m'"'. ny^  „,  r^^~oi.i 

ôv'^  =  —- ^-^.a'v.p  ;  .  5v''=-- --——.a\Pl.  [44/26] 

(5  7i>-— 2  n")2  -  (5nv— 2n'^)2  ^ 

Hence  it  is  evident  that    (>  v"   is  easily  deduced  fi-om    5  v",  by  multiplying  this  last  quantity 
by  the  factor  [4473]  ;  so  that  we  shall  have, 

15  m'^.n"^.  a"    ,    . 
^v'-=—  .^„  „„-^v"'  [4472c] 

as  in  the  terms  of  the  fifth  dimension  of  the  excentricities  [3868a — cj. 


304  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

inec.uaii-  The  great  inequality  of   Saturn  is  composed  of  several  other  parts:    it 

S.        contains,  in  [3846] ,  the  function,* 

_j_av2  _/ — N    COS.  (5  rCt  —  27V''t  4-  3  i"  —  2  £'") 

[4475]  6V''  =  —  ^^:;--nn^  •  < 

-  a"  2 .  f  —  j  .  sin.  (5  71'  <  —  2  n'"  <  +  5  £»  —  2  s'^) 


[4476] 


[4477] 


[4478] 


[4480] 


[4481] 


5?i'  —  2  7t" 


Reducing  this  quantity  to  numbers,  we  find  in  1750, 

6  v''=  +  52%l3n99l.  COS.  (5  n't  — 2  n"t  +  ôs"— 2£'0 
—  1  P,275407  .  sin.  {brCt—2 1^  i  +  .5  s^  —  2  i")  ; 

and  in  1950, 

6  v^  =  +  51Sl 92839  .  sin. {5rC t  —  2n"t  +  bs''—^  s'") 
— 14^982033 .  cos.  (5  n^i  —  2  n"t  +  5  -='—  2  s"). 

Hence  we  deduce  the  value  of  this  function  for  any  time  whatever  t, 

6  v'  =  +  (52^138991  —  t .  0%0047308)  .  sin.  (5  7^1  —  2  n'^t  +  5  £"—  2  ;'") 
—  (11%275407  +  ^.  0',01 85331)  .cos.  (5  n't  — 2  7i"t  +  ôs-'—2B"). 

The  great  inequality  of  Saturn  contains  also,  in  [3846],  the  term, 

[4479]  5  w^  =  —  4  //'  e" .  sin.  (  5n''ï  —  2  n'^ i  +  5  £"  —  2  e'"—  ^»  +  A'). 

This  term,  in  1750,  is, 

6v''  =  +  7%554290  .  sin.  (5  ift—2  n"'t  +  5  e"—  2  £*") 
+  5',321290  .  cos.  (5  n't  — 2  n"t+  5 s'  —  2  s")  ; 

and,  in  1950,  it  is, 

a  v"  =  +  7%71 1294 .  sin.  (5  Wt  —  2n"'t  +  5i'  —  2  s") 
+  4^825821  .cos.(5n''t—2n"'t  +  ôs''  —  2e"'). 


*  (2682)  The  expression  [447 o]  is  similar  to  [4419],  in  Jupiter's  theory,  and  is 
[4475a]    computed  in  the  same  manner  ;    namely,  by  finding  tlie  values  of    (    >  v  ')'    ("TT  )' ^'^^ 

similar  to  [4420]  ;  which  maybe  easily  done,  by  means  of  formula  [4421],  and  the  values 
[4475t]    [4420].     Then  from  [3842, 3843],  we  get     (t-;).    (j^X^'^-      It  is  useless,  however, 

to  explain  the  details  of  this  computation,  as  it  is  done  in  almost  exactly  the  same  way  as 


VI.  xiii.  §  35.] 


THEORY  OF  SATURN. 


305 


Hence,  for  any  time  t,  it  becomes, 

6  r"  =  +  { 7'-,554290  +  t .  0\000785 \  .  sin.  (5  n'i  —  2  w" i  +  5  s^-  —  2 ;'^) 
+  {5^321290  —  t .  0%002477 \  .  cos. (5 nH—2  n"t  +  5  î'—  2 é"). 

The  part  of  Saturn's  great  inequality,  depending  on  the  poivers  and  products 
of  five  dimensions  of  the  excentricities  and  inclinations  of  the  orbits,  is,  by 
[3846,4023],* 


[4482] 


for  Jupiter  ;  we  shall  tlierefore  only  observe,  that  the  expressions  [4476,  4477,  4478,  4479, 
4480,  4481,  44S-2,]  correspond  respectively  to  [4423, 4424,  4425, 4426,  4427, 4428,  4429]. 

*  (2683)  From  the  terms  of  R,  of  the  third  dimension,  depending  on  P,  P'  [3810], 
we  have  deduced  in  the  two  first  lines  of  [3844],  the  corresponding  terms  of  S  v;  which 
ai-e  afterwards  developed  in  [4022,4023],  according  to  the  powers  of  t;  and  the  same  process 
may  be  a))plied  to  the  two  first  lines  of    5  v'    [3846].       We  may  also  derive  these  tenns  of 

S  11',  from  the  corresponding  ones  of    5  v,    by  multiplying  by  the  factor — —- — ,     or 

ISm'^'.n'a.a 


rather  by 


6  m'.  rfi.  a 
as  is  evident  by  the  inspection  of  the  formulas  [3844,3846].  We  may 


[4475f] 

[4483a] 

[4483i] 
[4483c] 


proceed  in  exactly  the  same  manner  with  the  terms  of  R,  of  the  fifth  dimension,  depending  on 
P„  PI  [3863],  or  with  those  of  il',  depending  on  P„,  P,/[3865];  the  only  change  requisite 
is  to  place  the  accents  below  the  letters  P,  P'.  Now,  if  we  neglect  the  parts  of  [4023] , 
depending  on  t"^,  ddP,  ddP',  and  make  the  above-mentioned  changes  in  the  factor 
and  in  the  accents  of  the  remaining  terms  ;  also  putting  P, ,  for  P„  ,  and  Pf,  for  P„'  [3864è],  [4483(/] 
we  shall  get,  for  S  v''  the  expression  [4483],  depending  on  quantities  of  the  fifth  order  in 
e",  e",  y.  In  finding  the  values  of  P, ,  P/,  we  may  observe  that  the  function  R  [3859] 
is  easily  reduced  to  the  form  [386-3],  by  the  method  explained  in  [3842i,&c.]  ;  using  the 
values  of  A'"»,  A"*",  &ic.  [4430],  by  means  of  which  we  obtain  the  expressions  of  a^.P  , 
a\P;,  [4434,4485],  for  the  two  epochs  of  1750,  1950.  The  difference  of  these  two 
expressions  being  found,  and  divided  respectively  by  200,  give  the  values  [448C]  ;  as  is 
evident  from  the  formula  [3723].  Substituting  [4484,  4486],  in  [4483],  it  becomes  as  in 
[4487].  The  signs  of  all  the  terms  [4434—4487],  are  different  in  the  original  work,  being 
changed,  as  in  [4430a],  to  correct  the  mistake  mentioned  in  [3860a].  JMoreover,  to  rectify 
this  mistake  in  the  signs,  it  is  necessary  to  add  the  expression  2  (S  j;"  [4487]  to  the  second 
member  of  the  great  inequality  of  Saturn  [4492,  &c.],  in  the  same  manner  as  the  similar 
value  of  2ÔV'''  [4431],  is  added  to  the  expression  of  the  great  inequality  of  Jupiter 
[4434,  &ic.].  The  numerical  coefficients,  in  [4434,  4491],  are  equal  to  those  given  by  the 
author;  but  the  corrections  C',  C,  2ôv'\  2  «5  «%  in  the  second  members,  are  not 
mentioned  in  the  original  work. 


[4483e] 


[4483/] 


VOL.    III. 


77 


306  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

fifth  order.      ,  -»  -.^ 

m  which    m'^P^,    m'^P/   [3863,  44836],    express  the  coefficients  of 

sm.  (ôn''t  —  2n''t  +  ôc'  —  2  ;"),         cos.  (5  n'  t  —  2  trt  +  5  -=^—  2  s'^), 
m  the  development  of  R,    depending  on  the  products  of  five  dimensions  of 
the  excentricities  and  inclinations.     We  find,  in  the  year  1 750, 

^4484^  a\  P,  =  0,0000068376  ; 

a\P;=  0,0000100087; 
and  in  the  year  1950, 
^4485j  a\P,  =  0,0000077132; 


[4486] 


[4487] 


[4489] 


consequently. 


a\P;=:  0,0000096940; 


a\  —'  =       0,0000000043780  ; 

at 

a\  i^  =3  —0,0000000015735. 

dt 


Hence  the  preceding  function  [4483],  reduced  to  numbers,  is, 

5v''=^  +  j^ 29%  144591  —t.  0%004081 }  .  sin.  (5  n't  —  2  )rt  +  5  s"—  2  s'") 
—  \  1 8',879594  +  t .  0-,01 1 356  j  . cos.  (5  n't  — 2  ir t  +  5  ="—  2  s''). 

Lastly,  we    have,  in  [4003],    the  sensilile  part  of  the  great   inequality  of 
Saturn,  depending  on  the  square  of  the  disturbing  force.     This,  in  1750,  is,* 

Sv'  =  —  3^,816537  .  sin.  (5k^7— 2îi'^i  +  5  s'— 2  s") 
[4488]  +  42^,92031 9  .  cos.  (5  n't  — 2  n'^ f  +  5  s"  —  2  .='") 

+  function  C  [4489/c]  ; 
and,  in  1950, 

6  tj"  =  —  1  %636772  .  sin.  (5  n''t  —  2n"t-\-5  =^'  —  2  r) 
+  43',624686  .  cos.  {ôn''t—2n"t  +  bf—2  ^") 
+  function  C'  [4489/t'] ,  nearly. 


*  (2684)  The  expression  of  &  v"  [4003] ,  being  developed  as  in  [3842a,J],  and  then  computed 
'■        "■'    as  in  the  last  note,  becomes,  according  to  the  author,  in  1750  and  1950,  as  in  [4488,  4489], 


Vl.xiii.  §35.]  THEORY  OF  SATURN. 

Therefore,  in  tlie  time    1750 +^   this  part  is  expressed  by, 


307 


respectively.     From  these  values,  tlie  general  form  [4490]  is  (leiluced,  by  the  method  used 

in  [44S3e,  &ic.]  ;  but  these  numerical  values,  of  the  function  [4003],  have  the  same  defects 

as   the    similar    expression   in    Jupiter's    motion    [4432],   of   which   we    have    treated    in     [44896] 

[4005(7 — 40076,  4431  rt — A].     The  corrected  value  of   Hv^',  given  by  Mr.  Pontécoulant  in 

the  paper  referred  to   in   [443 If],  is   as  in  the  following  table,  which  is  similar  to  that  of 

Jupiter  [4431/,&c.]. 

Ô  v'=       2',17020  .  sin.  T^  +  0' ,23185  .  cos.  Tj 

1  +  8^14230  .  sin.  T^  +  P,8S43S  .  cos.  Tg 
1'  +  4^891 14  .  sin.  T^  —  P,067G9  .  cos.  Tg 
2-  _  0,951 1 2  .  sin.  Tg  —  0',54669  .  cos.  Tg 

2  -f-  0',054SS .  sin.  Tg  —  0',830G0  .  cos.  Tg 

3  _  0',2576S  .  sin.  Tg  —  0%80208  .  cos.  Tg 
3'  +  P,74101  .  sin.  Tg  +  3  ,84548  .  cos.  Tg 

4  +  0',22091 .  sin.  Tg  +  0',2.3748  .  cos.  Tg 

5  +  r,85702  .  sin.  Tg  —  r,18481 .  cos.  Tg 

6,  G'  +  3',466n7  .sin.  Tg  -40%36260  .  cos.  Tg 

7,  i  =  2,  — 16^06895  .  sin.  Tg  +  ]  %9591 4  .  cos.  Tg 

7,  i  =  1,  +  6%04586  .  sin.  Tg  +  2',23454  .  cos.  1\ 

8,  z  =  2,  —  0%54808  .  sin.  Tg  +  1%29603  .  cos.  Tg 

=     10%7635G  .  sin.  Tg  -33',10557  .  cos.  Tg. 


Termg  of 

tlie  order 
of  the 
square  of 
the  dis- 
turbing 
forces. 


[4489c] 


This  differs  very  much  from  the  expression  given  by  La  Place,  in  [4488]  ;  which  is  connected 
with  the  other  terms  of  the  great  inequality  [4491],  after  multiplying  it  by  1 -j- fx'".  This 
multiplication,  by  1  -j-f^'")  is  not  strictly  correct;  because  some  of  the  terms  depend  on 
(1 +t^'')  •  (1  + /J-'))  and  others  upon  (1  +  (-^''Tj  ^'ut  as  jx''',  ij.",  are  small,  this  difference 
is  not  of  much  importance  in  this  small  inequality.  We  shall  therefore  adopt  this  method  of 
the  author,  as  we  have  already  done  in  the  similar  inequali:y  of  Jujiiter  [4431A,  &tc.]  ; 
where  the  factor  1  -{-[>■'',  is  used  for  all  the  terms.  Proceeding,  therefore,  as  in  [443lA,&;c.], 

we  shall  observe  that  the  mass  of  Jupiter  .  [4061ffj,  is  used  in  computing  [4489rf]  ; 

and  the  mass     ^n^?:^^n    [4061],    is  used  in  computing    [4488]  ;    and  if  we  increase   the 

expression  [4489(/].  in  the  ratio  of  1070,5  to  1067,09,  it  becomes  as  in  [4489iJ.  Subtracting 
the  expression  [4483]  from  [4489t],  we  get  very  nearly  the  correction  C"  [4489A;],  to  be 
applied  to  the  formula  [4491  or  4492].  We  must  also  apply  a  correction,  depending  on  à  ^, 
similar  to  that  of  5e  [443 Ip J,  in  the  great  inequality  of  Jupiter  ; 

6  v"  =  10^,79796  .  sin.  Tg  —  3.3%21 1 37  .  cos.  %  ; 
C' =  14',61450 . sin.  Tg— 76',I3169  .cos.  Tg. 


[4489rf] 

[4489«] 

[4489/] 
[4489g] 

[4489ft] 

Correction 

ofihe 
great  ine- 
quality. 

[4489i] 
[4489fe] 


308  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

6v'  =  —  {3',816537  —  t .  0',01 08988 1. sin. (ôn't  —  2 n'" ^  +  5 s''  —  2  e'") 
[44903  +{42^920319  +  t .  0%00352l8].cos.(5 n't— 2n"  t  +  5s'' —  2^'") 

+  function  C   [4489A:]. 
Now,  if  we  connect  together  the  different  parts  of  the  great  inequality  of 
Saturn,  we  shall   obtain  its  complete  value,  which  is  to   be  applied  to  ike 
planètes  mean  motion  ;* 

1+{2931%125445— <.0^0307355— ^2.0%0000450|  .sin/^'g^";"^^?) 
+  {223»-,252793-<.lM025051+i2.0^0001838|  .cos/^g^';^^^?) 
+  function   C"   [4489^']  +  2  <S  î;^   [4487] 

Great        Reducing  these  two  terms  to  one,  by  the  method  in  [4025 — 4027'],  we  shall 

mequality. 

obtain, 

C(O939»,615848-<.0^085024+i2.0',00008421).sin.  .y.-gog  +  fa   0-012676     ^f     ' 

[4492]       ,5t>'=-(l V)  <  i-t.// ,b^-\-t    .u,vi.4i}/i,     :)\ 

^4-  function   C^    [4489^-]+ 2  5i;^  [4487]  ^ 

The  square  of  the  disturbing  force  produces  also,  in  [3891'],  the  inequality,! 
[4493]  ôv'  =  ^  .     "'  '^"""i     "*  '^'^     .  sin.  (double  of  the  argument  of  the  great  inequality)  ; 

which,  in  numbers,  is, 
[4494]      ^«'=  (30  ,688957 — /.0',001 724).sin.(double  argument  of  the  great  inequality)  ; 
and  this  must  also  be  applied  to  the  mean  motion  of  Saturn. 


[4489i] 
[4489m] 


Professor  Hansen,  in  the  work  mentioned  in  [4458c],  makes  this  part  of  the  great  inequality 
of  Saturn,  in  the  year  1800,  as  in  [4489m],  using  the  masses  m'",  m'  [4061].  The 
corresponding  value  of  La  Place's  formula,  is  found  by  putting  t  =  50,  in  [4490],  by  which 
means  it  becomes  as  in  [4489o].  The  difference  of  these  two  expressions  represents  the 
value  of  C'  [4489p],  corresponding  to  the  calculations  of  Professor  Hansen,  noticing  all  the 
terms  of  any  importance  ; 
[4489n]  à  V-  =     15',476  .  sin.  Tj  —  47',531  .  cos.  Tg  ; 

[4489o]  àv'  =  —  3',271  .  sin.  Tj  +  43',096  .  cos.  T^  ; 

C>-  =     1 8',747  .  sin.  T^  —  90',627  .  cos.  T^. 
*  (2685)  The  function  [4491]  is  the  sum  of  the  expressions  [4474,4478,4482,4487,4490]; 
and  this  sum  is  easily  reduced  to  the  form  [4 192],containingbut  one  term,by  the  method  explained 
in  [4025—4027'].     There  is  a  small  mistake  in  the  calculation  of  the  term    223' ,252793 
[4491],  which  in  the  preceding  sum  is  223',900794;   the  difference  being  0',648  =  2". 
(4493a]         t  (2686)      The    term   [4493]  is  the  same  as  [-3891'],    —H'    [3891]  being  the  great 


[4489;?] 
[4491a] 


VI.xiii.§35.]  THEORY  OF  SATURN.  309 

The  inequality  [3927],* 

reduced  to  numbers,  is, 

6  1"=  +  8',26451 7  .  sin.  (4  n'"  /  —  9  n"  /  +  4  s''—  9  s^'  +  51''  49'"  37').  [4496] 

We  have  also,  in  [3846],  the  inequality,! 

ôv'=  l;K'  e' .  sin.  (Sn't  —  2  n'^7  +  3  s"  —  2  ="  +  ^'  +5')  ;  [4497] 


inequality  of  Saturn,    or 

5' =2939%61 5848  — <.  0^085024,     and     :ï'=4''2r' 20%  nearly    [4493]:  [44936] 

substituting  this   and  the  values   of    m"-',    irû',    a'",    a"  [4061,4079],  and  dividing  by  the 

radius  in  seconds  206265%  for  the  sake  of  homogenity,  we  get  ô  v"  [4494].    The  correction 

in  the  value  of  H'  [4483/],  has  a  slight  efiect  on  this  result  ;  and  the  same  may  be  observed     '■  ' 

relative  to  the  correction  of    H  [4483/],  in  the  term  [4436]  ;  and  in  other  terms  depending 

on  H,  H- 

*  (2687)     The  inequality   [4495]   is   the  same  as  [3927],  increasing  the  accents  as  in 

[4388n].     Now  we  have  nearly  as  in  [44936], 

F=2939%615848,  :3'  =  4''21"'20'  [44936]  ;  [4495o] 

and  by  comparing  the  expression  [3925]  with  the  third  line  of  [4468],  we  get,  by  neglecting 
the  teiTus  depending  on   t, 

K  =  669%682372,  B'  =  —  bQ^  10'"  57'.  [44956] 

Substituting  these  in  [4495],  it  becomes, 

-f  9%2107  .sin.  (4?i'>7  — 9?j^-r  +4  £''  — 9  £^4-51'^49'"  37»).  [4495c] 

In  the  original  work  the  coefficient  has  a  difterent  sign,  being 

—  25",507770  =—  8%264517, 

also  the  angle    — B' — Â' ,    as  given  at  first,  is, 

—  67°,3508  =  —  GO-*  36"'  57'.  [4495rf] 

These  mistakes  are  corrected   by  the  author  in  [9105],  where  the  coefficient  is  made  equal 
to    +8',264517,  and  the  angle    —  B — .?=  51"  49"  37'  nearly. 

t  (2688)     This  is  the  same  as  the  last  line   of  [3846],  increasing   the  accents  as  in     r4497„n 
[4388a]. 

VOL.  III.  78 


310  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

and  by  reduction  to  numbers,  it  becomes  in  1750,* 

[4498]  6  v"  =  47%  115141  . sin.  (2  n'' t —  Sn"  t +  2  e'"—  3 s"  +  US''  08'"  08^  ; 

and  in  1950, 
[4499]  6  V'  =  46',307169  .  sin.  (2 n"t  —  Sn''t-\-2  i""—  3  ='  +  U9'  41'"  \&). 

Therefore  its  value  for  any  time  whatever   t,    is, 

^^5Q(j^      5u'=(47%115141  — <.0%0040399).sin.(27r<— 3?rt-[-26i>'— 3£^+148''08"'08'+^27%94). 
Connecting  this  expression  with  the  following,  obtained  in  [4466], 

èv"  =  +  (34V341627  — i.0%0019).sin.  (3n^t—2nrt+3s'—2^''—z^) 
^''^"^^  —  1 7%6541 64  .  sin.  (3  7i^t  —  2  rr  t +  3^" —  2  s''' —  «''')  ; 

we  shall  obtain  for  their  sum,  the  following  inequality,! 

[4502]      s  1)'=:—  (24^571253— < .  0',004392).sin.(2?i''Y— 3  ?i^-<+2s'^— 3  e^+14''48'"19*— M2',38). 

We  have  found,  in    [3777],  that  Saturn's  mean  motion  is  subjected  to  a 
secular  equation,  corresponding  to  that  of  Jupiter  in  [4446],  namely, 

[4503]  êv"  ^  —  t"".  0  ,00000065. 

The  corresponding  secular  equation  of  Saturn  is  represented,  as  in  [3777], 

by,t 

[4504]  6  v"  =  -^^  .  f.  0"-,00000065  ; 

and  is  therefore,  in  numbers, 
[4505]  6v'  =  fA)%00000\51; 

which  may  be  neglected  without  any  sensible  error. 

*  (2689)     If  we  retain  the  terras  depending  on  t,  in  the  values  of  K',  B'  [4495i,4468], 
we  shall  have, 

K'  =  669',682372  —  t .  0',015469  ;  B'=  —  SG''  10""  57^  —  i .  49'-,5  ; 

[.4498a]  ^  =  ^i2\^<  20'—  t .  77%629     [4492,  3926],  &ic. 

With  these  values,  and  those  of  e^,    zf  [4407],  we  may  compute  the  function  [4497],  for 
[44986]     the  j-ears  1750,  1950,  as  in  [4498,  44S9];   hence  we  may  deduce  the  general   expression 
[4500],  by  the  same  method  as  in  [4017—4021]. 

[4502o]         1(2690)     This  reduction  is  made  as  in  [42S2/t—r]. 

[4505o]         t  (2691)     The  integral  of  [3777  or  3785],  being  divided  by    m'\/a',  ^ives, 


Secular 
equatiun. 


VI.xiii.§35.]  THEORY  OF  SATURN.  311 

It  now  remains  to  consider  the  radius  vector  of  Saturn.  We  have  seen, 
in  [3847],  that  the  terms,  depending  on  the  tliird  power  or  product  of  the 
excentricities,  add  to  the  expression  of  the  radius  vector  of  Saturn,  the 
quantity,* 

6r'  ^  —  H'  a\  e\  cos.  (5  n't  — 2  n"t  +  5  £"  —  2  ^'—  ^'  +  A) 

+  H'  a\  e\  COS.  (3  n't  —  2  n"t  +  3  s>'  —  2  s-  +  ^^  +  A)  ^450^^ 

10  m".  n\  a'-^  C       P  .  sin.  {5)i't  —  2  n'^i  +  5  s^—  2  s'")  ) 
5  n'—  2  n"  '(-\-P'.  cos.  (5  yt^i—  2w"7+  5  e^—  2  s'")  ^  ' 

Reducing  this  function  to  numbers,  we  obtain, 

,   (  +0,00351994565.cos.(5n''i— 2n'''^+5  .^— 2s-+  13^01'"490  ) 

6r''^(l  +  (A"').<  ^  >.       [45071 

(_0,0008553506.cos.(2/rf— 3n^i+2s"— 3s'  +  35''49"'080^       ^       ^ 


nequQli- 
ties  in  the 


Connecting  the  last  of  these  two  inequalities    with   those    we  have  found    1 
in    [4467],  depending  on  the  first  power  of  the  excentricities,  namely,  ^^^'j»» 

V     .1,    i„x   ^  + 0,001 1594872.  cos.  (3/1^^  —  2 ?r/  + 3s'— 2 s'-'—^M) 

^  (  — 0,0006217670.cos.(3n"i  — 2n'''^  +  3£'— 2  s"'  — ^'0^ 

we  get,t 

0  r"=  —  (1 4-  f^'") .  0,0013806201  .  cos.  (Zn'^t—S  n't+2  s'"— 3  s"— 23'^  19"  18').      [4509] 


the  accents  being  increased  as  in  [4.38Sa] •     Substituting    Sv'"  [4503],  we  get  Sv"  [4504], 
which  is  reduced   to   numbers   as   in    [4505],    by  using    the  elements    m'",    m"' ,    «'",    a"    [4505c] 
[4061,4079],     This  correction  is  only    1*,5,    in  1000  years,  which  is  hardly  deserving  of 
notice. 

*  (2692)     The  function  [4506]  is  the  same  as  the  three  last  terms  of  [3847],  multiplied 

by    a',    and  increasing  the  accents  [4388a]  ;  the  first  term  of  [3847]  being  of  the  second 

order    in     e,    e',    y,   is  included   in  [4170].     H  represents  the  part  of    — -;-      [3848],    [4506a] 

depending  on  the  angle      4  n"  t  —  2  li"  t  ;    P,     P',  are  given  in  [4402,  &ic.].     Hence  the 
expression  [4506]  becomes,  in  numbers,  as  in  [4507]. 

t  (2693)     The   function   [4508]  is  the   same  as  the   fourth  and   fifth   lines  of  [4467]. 
Connecting  these  with  the  similar  terms  [4507],  and  reducing  the  whole  to  one  term,  by  the    [4509a] 
method  in  [4282A — /],  it  becomes  as  in  [4509]. 


312  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

The  semi-major  axis,  which  is  used  in  calculating  the  elliptical  part  of  the 
radius  vector,  must  be  increased  as  in  [4058],  by  the  quantity  ^a'-m''; 
and  hy  adding  it  to  the  value   of    a"    [4079],  we  obtain, 

[4510]  «^  =  9,53881757. 

Inequalities  of  Satimi^s  motion  in  latitude. 
SQ.     The  formula  [1030]  gives,* 

+  ]  %787358 .  sin.  {n"  t  +  b"  —  n^) 

—  0',2501 80.  sin.  (2  n'-'t  —  n't  +  2  é"  —  s"  —  n^) 
0',083g46 .sin. (3 n' 't —  2n'' t  +  3  s"—2s'' —  n") 

^^^-  ]  +  3%  1 43523 .  sin.  (2  n' t  —  n"l  +  2  j"  —  s"  —  n') 

—  0%522865 .  sin.  (3  n't  —  2  n"t  +  3  .-"  — 2  s"  — n") 

—  0',083182.sin.(4n"f  — 3n"'i+4,£''— 3£'^— n^) 
[4511]                                           ^ 

Ç  +  0%084871 .  sin.  (n'"'  t  +  ^'■'  —  n") 

^(l_^p.-)  .  3  +  0',122203.sin.(2n"f— n^f +  2£^'  — ^=^— n") 

/  +  0',662991 .  sin.  (3  n^'t  —  2n't+  3  £''—  2  £^—  n^') 

n',    being  the  longitude  of  the  node  of  Jiipiter''s  orbit  on  that  of  Satnrn, 
[4512]     and    n"',    the  longitude  of  the  orbit  of  Uranus  on  that  of  Saturn.     Lastly, 
we  have,  in   [3886],  the  inequality ,t 

[4513]  6s'  =  —  9',  163599  .  sin.  (2 n'^t  —  An't  +  2s-  —  4 s^+dd' 30™ 350- 

It  follows,  from  [3932,  3932'],  that  the  terms  depending  on  the  square  of  the 

disturbing  force,  add  to  the  values  ot     — -,      —,     the  quantities,! 


*  (2694)     The   terms   of    5  s'''     [4511],   are    computed  from  [4295i],    increasing    the 
"      accents,  so  that    m"  may  be  the  attracted  planet,  and    m'''  or  ot''  the  disturbing  planet. 

f  (2695)      The    inequahty   [4513]  is  the  same  as  [3886],  reduced  to  one  term,  as  in 
[4513a]     [4282/t— Z]. 

t  (2696)     The  values   [4514,4515],   are  deduced  from    [3932,3932'],  in   the  same 

[4514a]     manner  as   [4452,  4453],  are  derived  from    [3931,3931'].      We  may  also  derive  [4514] 

from    [4452],    and   [4515]    from    [4453],  by   the    following    method.       The    expressions 


VI.xiii.§36.]  THEORY  OF  SATURN.  313 

■rf,v ,«ivva^      Sir,^os.(n-n-'-^.sm.(u-é^)h  [4514] 


de" m'\ y/»'"  iSj     .^^  ^^       ^^^   ^_  ySn 

dt         m'\  s/a'"-^  m\  /«"    (  t 


'.sin.(n— (r)+  ^— .cos.(n— â')^ 


^7,     6n,    being  determined  as   in  [3935,3936].      Reducing  the  functions 
[4514,  4515]  to  numbers,  we  get, 

do?'' 


[4515] 


=  _|_  0',000154;  [4516] 

==._0\001873.  [4517] 


[4518] 


dt 

de" 

77 
Tire  expression  [4516]  is  to  be  added  to  the  valuesof     -p,       -^    [4247]; 

d  è^  d  è^ 

and  the  expression  [4517]  is  to  be  added  to  the  values  of    -jj- ,      — ^   [4247]. 

Hence  we  obtain, 

^  =.  +  0',099894  ; 
dt 

'^'  =  —  0%  155136; 
dt 

—  =_9,007165; 

dt 

1^  =  — 19%043372. 
dt 


[3931,3931'],  become  the  same  as  [3932,3932'],  respectively,  by  changing,  in  the  second 
members,    è    into    à',    and  multiplying  by — .      This  is  equivalent,  in  the  present     [4514A] 

notation,   to  the  change  of    ê",    into    ê",    and  then  multiplying  by  the  factor —  . 

Therefore,  if  we    perform  this  operation   on   the    fonnulas    [4452,4453],  they    become     ^4514^1 
respectively,  as  in  [4514,4515];    in  which  we  must  compute    (5  7,    5  IT,  as   in  [4452A]  ; 
and  then,  as  in  [4452/t,  &c.],  we  obtain  the  other  quantities  [4516,  4517,4518]. 

We  have  already  remarked,  that  the  inequalities  of  the  motion  of  this  planet  are  again 
noticed  by  the  author,  in  book  x.  chap.  vili.  [9037,  &c.],  and  the  subject  is  also  resumed  in 
the  notes  on  this  part  of  the  work. 

VOL.  III.  79 


314  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél 


CHAPTER   XIV. 


THEORY  OP  URANUS. 


37.     The  equation  [4460], 

[4519]  6r^=^.(l—a?).ô\\ 

corresponding  to  Saturn,  becomes  for  Uranus, 

[4520]  ôr^'^'^.n—  a=)  .  <S  V". 

r 

If  we  take  the  mean  distances  of  the  earth  and  Uranus  from  the  sun,  for    r", 
and    r",    and  sup]30se     â  V"'=:  ±  1"=  ±0,324,     we  shall  find, 

[4521]  Ô  r"  =  ±  0,00057648. 

l^™^  Therefore  we  may  neglect  the  inequalities  of  5  r",  below  ±  0,00057  ; 
"sLwd.  and  we  shall  also  omit  the  inequalities  of  the  motion  of  Uranus,  in 
[4522]     longitude  or  latitude,  below  a  quarter  of  a  centesimal  second,  or  0%081. 

Inequalities  of  Uramis,  independent  of  the  excentricities.* 

+52%306055  .  sin.    {n"'t  —  n'H  +  e"  —  £^') 

—  0',  190366  .  sin.  2(n'U  —  n'H  +  s"  —  ^'") 
6«''=(1  +  H'")  .  {  —  0',026023  .  sin.  3(n"^  —  n''H  +  s-  —  s^*) 

^'^^^^^  '  —  0%003593  .  sin.  4  («'"  t  —  n'H  +  s"  —  i-') 

—  0',000768  .  sm.b{n"t  —  n^H  +  «'"—  s"') 


*  (2697)    Computed  as  in    [42T7«,  &ic.],  changing  the  accents  on    a,    ii,   n',  &,c.  to 
"•'     conform  to  the  case  now  under  consideration. 


Vl.xiv.  §37.] 


+  (1+^-") 


THEORY  OF  URANUS.  315 

+2P,371379  .  sin.    (n't  —  rûH  -\- i' —  i") 

—  4--,220972 .  sin.  2{n''t  —  n'H  +  b"  —  e^') 

—  0  ,8621 15  .  sin.  3(n''t  —  n"  t  +  s^  —  s") 

—  0%2444U9  .  sin.  4  (ît'  t  —  n"  t  +  e"  —  s")  \  .  [4523] 
^  _  0',08U21 1  .  sin.  5  (n"  t  —  n""  i  +  e"  —  s^') 

_  0-,028931  .  sin.  6  (h"  t  —  7t"  <  +  s"  —  £"0 

—  0',01 0929  .  sin.  l{nH  —  ri"  i  +  s'  —  s") 

—  0%004148  .  sin.  ^{ift  —  n'H  +  ^'  —  e") 

Inequali- 
ties inde- 
pendent of 
thd  exGÊQ~ 

0,0063473160  \  fi"«i«- 

+  0,0048914790 .  cos.  {ii}'t  —  rf't  +  s'''—  ^'") 
5rvi=(H-^-)  .  /  +  0,00002361 84.  cos.  2  (7i"i  —  n^'^  +  ^'^—^'0 
+  0,0000030669  .  cos.  3  {n'H  —  n'H  +  s-_  £") 
+  0,0000005044.  cos.  4(w'''i  —  nH  +  s'"—  ^'0 

+  0,0023641285 

+  0,0035433901 .  cos.  (n"  t  —  n'H  +  B"  —  s"') 

_(.-(l  +  ^v)  _  I  ^  0,0004061682 .  cos.  2(n't  —  n"i  +  s"  —  s") 

+  0,0000889425  .  cos.  3  (n"  t  —  n^'t  +  e-  —  s^') 

+  0,0000255870  .  cos.  4>  (n" t  — n"t  + ^''—s'") 

Inequalities  depending  on  the  first  power  of  the  excentricities* 

—  1%233612  .  sin.  (n'"  t  +  s"  —  ^^') 
+  r,25954B  .  sin.  (2  n'H  —  n'H  +  2  8'"  —  /'—  w'") 

«jy-  =  (1  +  (^'O  .  j  _  3.^g3g663  _  sin.  (2  r^^  —  ?r<  +  2  s^'  —  s'"  —  t."') 

—  0^221997  .  sin.  (2  w^'f  —  n'H  +  2  s"  —  a"  —  to*") 


[4524] 


[4525] 


*  (2698)     These  inequalties  were  computed  in  the  same  manner  as  those  for  Jupiter    [4525a] 
in  [4375a]. 


Inequali- 
ties de- 
pending on 
tho  first 


tncities. 


316  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

—  P,402359  .  sin.  (n^'t  +  i"  —  w") 
+    0',214857  .  sin.  (n"  t  +  s^  —  ^^  ) 

—  0^219788  .  sin.  (2  n"  t  —  if  H  +  2  s'—  s"  —  îj^') 
&1                         \  +    0',878763  .  sin.  (2  rVt  —  if  H  +  2  e>—  s^''  —  ^^) 

—  (44S051575  —  t .  0',000247) .  sin.  (_5!v,'^^^, 
[4525]      +  (1  +  f^O  •  (  _j_  (1 49',807764  —  i . 0^008306) . sin.  (_^S7~J[^^ 

+  2%486191  .  sin.  (3  «"i  —  2  ?i^'^  +  3  s"—  2  s"  —  ^") 

—  r,642451  .  sin.  (3  ji^'/  —  2  ?j'7  +  3  s''—  2  s"  —  ^^) 
+  0',422729  .  sin.  (4  n"ï  —  3  n-'  ^  +  4  s"  —  3  s'  —  «^') 

—  0',281 800  .  sin.  (4  n'H  —  3  «"i  +  4  e''  —  3  s'  —  ^^  ) 
+  0^  1 26493  .  sin.  (5  n"'^  _  4  »^7  +  5  s^'  —  4  e^  —  ::i") 

(  _  0,0016092001  .  COS.  (2n'H  —  ift  +  26^'  — s^— ^^')  ) 

[4526]        Ar^'=('l+M'').  <  >. 

^  ^    J  +  0,0061835858.  COS.  (2n^'i  —  ?r^  + 2  s^'—E"—.^-)  C 

Inequalities  depending  on  the  squares  and  products  of  the  excentricitîes  and 

inclinations  of  the  orbits.* 

^(132^508872-t0^0145205).sin.(i-37 -^^^^^^^        f^Tg'^^)  \ 
[4537]      6r^"=(l+0.j  _!_     i^-,7i3455.sin.(4?i^'i  — 2?r^+4/'— 25'— 38''34"'54'')1- 
J^oAt  (  +     8^380157 .  sin.  (n"  t  —  ii''H  +  a'  -  /'  +  88"29"'  40^         j 

second 

The  first  of  these  inequalities  must  be  applied  to  the  mean  motion  of  the 
planet,  on  account  of  the  length  of  its  period.  The  last  of  these  inequalities, 
being  connected  with  the  corresponding  one  in  [4523],  which  is  independent 
of  the  excentricities,  gives  the  following,! 

[4528]  &  r^'  =  (1  +  f^')  •  23^156281  .  sin.(n^^  —  ii'''  t  +  i^'—  e^'  +21^1"  05^. 


[4527o]         *  (2699)     Computed  as  in  [4377a, &c.],  for  Jupiter. 

t  (2700)     The  term      +  (1  +  f^"). 2^,37 1379. sin.  (n'<  —  n^V  +  s'— £>')      [4523], 
[4528a]    being  connected  with  the  last  term  of  [4527],  by  the  method  used  in  [4282A — /],  becomes 
as  in  [4528]. 


Vl.xiv..^3S.]  THEORY  OF  URANUS.  317 

Tiieu  we  have,* 

ô  ,•'■'  =  _-  (1  +  (x^)  .  0,0007553840  .  cos.  (3  n'H  —  n't +  3  s"—  5^+75"  00"  42^.      [4529] 

Inequalities  depending  on  the  poiver.t  and  products  of  three  dimensions 

of  the  excentricities  and  inclinations  of  the  orbits.f  twîd'""' 

order. 

S  r'-  ^  —  (1  +  M-^)  .  0',964688  .  sin.  (5  n"  t  —  2n't  +  ô  s"—  2  s'  +  OS''  23"  3P).      [4.53oi 

Inequalities  of  the  motion  of  Uranus  in  latitude. 
38.     From  the  formula  [1030],  we  obtain,t 

6  5^'  =  (1  + ,.-)  .  0%638393 .  sin.  (ra'^  t  +  s"—  n'^) 


Inequali- 
ties in  the  . 
latitude. 


(      0',9 15741.  sin.  (w^^  +  s^—n")  )  [4531] 

^  (  +  2',921052.sin.(2w^-i  — n^ï+2£"— s''— m)^ 

n"    being  here  the  longitude  of  the  ascending  node  of  Jupiter's  orbit  upon 

that  of  Uranus,  and  n'   the  longitude  of  the  ascending  node  of  Saturn's  orbit     ^       ^ 

upon  that  of  Uranus. 


*  (-2701)     Computed  as  in  [4394«,  Sic]  for  Jupiter.  r4529al 

t  (2702)     This  computation  is  made  as  in  [4417,  &c.]  for  Jupiter  ;  changing  the  accents 
to  conform  to  the  present  notation.  [4530a] 

t  (2703)     The  terms  [4531]  are  computed  from  the  formula  [4295è],  altering  the  accents 
to  conform  to  the  present  case.  [4531a] 


VOL.  III.  80 


318  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


CHAPTER   XV. 

ON  SOME  EQUATIONS  OF  CONDITION  BETWEEN  THE  INEttUALITIES  OF  THE  PLANETS,  WHICH  MAV  BE 
USED  IN  VERIFYING  THEIK  NUMERICAL  VALUES. 

39.  The  inequalities  of  a  long  period,  produced  by  the  reciprocal  action 
of  two  planets  m,  and  m',  are  nearly  in  the  ratio  of  m'\/a'  to  — m\/a 
[1208]  ;  so  that  to  obtain  the  perturbations  of  this  kind,  corresponding,  in  the 
motion  of  m',  to  those  in  the  motion  of   m,  loe  need  only  to  multiply  the  last 

[4532]      lyy ^^_     T\ù%  result  is  most  to  be  relied  upon,  in  those  cases,  in  which 

the  ratio  of  the  mean  motions  of  the  two  planets  is  such,  as  to  render  the 
period  of  these  inequalities  great,  in  comparison  with  the  times  of  their 
revolutions.  We  shall  now,  by  means  of  this  theorem,  verify  several  of  the 
preceding  inequalities. 

The  action  of  the  earth  on  Venus  produces,  in  [4291],  the  two  following 
inequalities,  whose  period  is  about  four  years, 

àv'^—  1%5 49550 . sin.  (3  n"t  —  2  w'^  +  3  s"—  2  s'—  ^') 
+  4',766332. sin.  (3  n"t  —  2 n't  +  3="  —  2  /  — ^"). 

By  multiplying  them  by  — ^^^ryr,?  we  have,  for  the  corresponding  inequality 
of  the  earth, 

hv"^      P,  1 33838  ,  sin. (3 n"t —  'Un' t -\-S i'  —  2 .'  —  ^) 
—  .3'-,487666  .  sin.  (3  n"^  —  2  ?î'i  +  3  ;"  —  2  /  — ^■'). 

We  have  found,  by  a  direct  calculation,  in  [4307],  that  these  inequalities  are, 

hv"=      r,186390  .  sin.  (3n'7  — 2  n'i+  3s"  — 2s'_^') 

^3%667112.sin.  (3h"^  — 2n'i  +  3.-"  — 2=-'— ^"); 


[4533] 


Venus 
and 
the  Earth 


[4534] 


[4535] 


VI.  XV.  §39.]  VERIFICATION  OF  SEVERAL  INEQUALITIES.  319 

which  difTers  but  little  from  the  preceding  expression  [4534]. 

The  action  of  the  earth  upon  Venus,  produces  also,  in  [4293],  the  following 
inequalitv,  whose  period  is  about  eight  years, 

6v'  =  —  \  -,505036 .  sin.  (5  n" i  —  3  n' i  +  5 s"—  3  e'  +  SO''  54"' 26').  [453G] 

Multiplying  it  by, ,,     „,   we  obtain,  for  the  corresponding  inequality  of 

the  earth, 

ôv"=  l',101277.sin.  (5  n"t  — 3  n't  +  ôs" —  3  s' -\-20''54>'"2&)  ;  [4537] 

and,  by  a  direct  calculation,  we  have,  in  [4309], 

6  v"=  r,  125575  .  sin.  (5  n"t  —  3n'  ^+5  /'—  3  s'  +  2 1-;  02"' 18').  [4538] 

Mars  suffers,  by  the  action  of  Venus,  as  we  have  seen  in  [4377],  the  following 
inequality  of  a  long  period, 

è  v"'=  —  6',899619  .  sin.  (3  n"'t  —  n't  +  3  £'"—£'+  65" 26'"15').  [4539] 

„T  ,  •  ,  •      -,  m"V«"'  1     • 

Multiplying  It  by y—- ,     we  obtain,  fnd' 

™  \/«  Mars. 

5 v"  =  2%078266  .  sin.  (3  n'" t—7i't  +  3  /"  —  /  +  65'  26"*  1 5')  ;  [4540] 

and  the  direct  calculation  [4293]  gives, 

6 v'  ^  2',009677  .  sin.  (37i"'t  —  n't +  3 /"  —  s'  +  65'  53"' 09')  ;  [4541] 

which  differs  but  little  from  the  preceding. 

Mars    suffers,   from  the  action   of  the  earth   [4375],  the  two   following    TheEarti, 
inequalities,  whose  period  is  about  sixteen  years,  mIL 

S  v"'=  —  10',1 14699  .  sin.  (2  n"'t  —  7i"t+  2  s'"  —  a"—  t,'") 

+    5',  1 23062  .  sin .  (2  n'"  t  —  n"  t  +  2  a"'  —  e"  —  ^") .  ^''^''^^ 


m'  \/a"' 
Multiplying  them  by    —  "^;^;^  '  ^"^'^  obtain,  for  the  corresponding  inequalities 

of  the  earth, 

6  v"  =      2',2293  .  sin.  (2  n'" t  —  n" t  +  2s"'  —  i'  —  •=='") 
—  1  -',  1 292  .  sin.  (2  jj'" t  —  n!'  t  +  2  a'"  —  a"  —  t^")  ; 
and  the  direct  calculation  gives,  in  [4307], 


[45431 


320  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


[4544] 


6  v"  =      2%  1 37658  .  sin.  (2  n'"  t  —  n"t  +  2  s'"  —  s"  —  ^"') 
—  P,095603  .  sin.  (2  n"'t  —  n"t  +  2  b'"  —  s"—  v!')  ; 

which  differ  but  little  from  the  preceding. 

Mars    also   suffers,  on   the  part  of  the   earth,   in  [4377],  the   following 
inequality  of  a  long  period, 

f4545j  i  v"'=  —  4%370903  sin.  (4  n!"  t—2n"t  +  4>  s'"—  2  «"  +  67''  49"'  OOO- 

m"'\/a"' 
Multiplying  it  by iryui    we  obtain,  for  the  corresponding  inequality  of 

the  earth, 

f 4546]  <5  v"  =  0-,9634 .  sin.  (4  n'" t  —  2  n"  t  +  4  -="'  —  2  e"  +  67''  49"  00»)  ; 

which  differs  but  little  from  the  expression,  given  in  [4309], 

[4547]  6  v"  =  0-,993935.  sin.  (4  n'"  t  —  2n"t-{-4>  s'"  _  2  s"  +  67"  48™  56'). 

^"and"  The  two  great  inequalities  of  Jupiter  and   Saturn,  are  also  to  each  other, 

^""'"'       nearly  in  the  ratio  of    — 77f\/a''     to     m'''\/a"',    as  is  evident  by  comparing 
[4548]      |-4434^  4492]. 

Saturn  Lastly,  Urauus  suffers,  from  the  action  of  Saturn,  the  following  inequality 

and 

Uranus,      of  a  long  period   [4527], 

[4549]  è  V''  =  —  1 32',508872 .  sin.  (3  n"' t  —  n't+Ss^'—  i'  —  SS"  19"  05"). 

Multiplving  it  by — ,     we    obtain,    in  the    motion  of    Saturn,  the 

inequality, 
[4550]  6  v"  =  32-,368  .  sin.  (3  7^1  —  n't +  3  e^'—  e"  —  88''  19'"  05^)  ; 

which  differs  but  little  from  the  inequality,  given  in  [4468],* 
[4551]  év"  =  30%888288  .  sin.  (3  n'H  —  n" t  +  3  e-—  s'  —  87"  25™  07')  ; 

40.     We  shall  now  consider,   in  the  development  of  R,  the  term  of  the 
form  [3745'], 


*  (2704)     The  term  here  referred  to  is  the  last  one  of  the  expression  [4468]  ;    which 
[4550a]     differs,  however,  a  little  ;  the  coefficient  being  31',025379,  instead  of  30%888288  ;  and  the 
constant  angf»-  85''34"'  12%  instead  of  87''  25"'  07'. 


VI.  XV.  §40.]  VERIFICATION  OF  SEVERAL  INEQUALITIES.  321 

R  =  «I'.ilf  ".  e  e'.  COS.  [  / .  (71'  ï  —  n  ï  +  e'—  <=)  +  2  n  <  +  2  s — ^  — ^')  I  ;  [4552] 

supposing  i.  (11  —  11!)  +  2  n  to  be  very  small  in  comparison  ivith  n  or  %'. 
We  find,  in  [1286,  &c.],  that  this  term  produces,  in  the  excentricity  e,  of 
the  orbit  of  the  planet  m,  considered  as  a  variable  ellipsis,  the  following 
inequality,  which  we  shall  represent  by,* 

ie=—.,  /'''t" — .M''\e'.co^.\i.(n't  —  n  i  +  a'— 0+  2  n  i  +  2  s  —  «  —  ^'|;     [45531 
i.{n — n)-\-2n  ' 

and  in  the  position  of  the  perihelion  ra,  an  inequality  [1294,  &c.],  which  we 
shall  represent  by, 

a^=_      /"'•""      .M<".-.  sin.  \  i.  (n't  _  ,i  i  +  6'—  0  +  2  n  i  +  2  e  —  ^  —  ^'  1 .     14554] 

i.(n  —  ?i)-|-2  7t  e  ^ 

The  expression  of  v  contains  the  term  2  e  .  sin.  Çnt  -j-  e  —  w)  ;  and  the 
variation  of  the  elliptical  elements,  produces,  in  this  quantity,  the  following 
expression,! 


[4.555] 


6v  =^  26e  .  sin.  (n  t  +  ^ —  w)  —  2e  6-si .  cos.  (nt+e  —  «)  ;  [4.5.5t)] 


*  (2705)     If  we  take  the  partial  differential  of  R  [1281],  relative  to    e,    and  multiply 
it  by -7;—, — .  ,  it  will   produce  the  corresponding  term  of  e,  represented  by  (5  e     [4553a] 


[4553i] 


[1286].  Now,  if  we  perform  the  same  operation  on  the  assumed  value  of  R  [4552],  and 
put  fx  =  1  [-3709]  ;  changing  also  i',  i,  into  i,  i  —  2,  respectively,  we  shall  get  (5 1 
[4553].  Again,  if  we  multiply  the  same  partial  differential  of  R  [1281],  relative  to  e,  by 
—  .andt,  putting  |j.  =  1 ,  it  becomes  like  the  expression  of  cdzi  [1294];  and  by 
the  same  process  we  deduce,  from   R  [4552],  the  expression, 

e  d-a  =  —  m'.andt .  JH''\  e'.  cos.  \  i.{n'  t  —  nt-\-  s  —  s)  -\-2nt  -\-  2  s  —  ra  —  zs'\.  [45.53c] 

Dividing  this  by  e,  and  integrating,  we  get  the  part  of  ra,  represented  by  0  w  [4554]  ; 
observing  that  we  may  consider  the  terms  31,  e,  e',  of  the  second  member,  as 
constant  quantities,  in  taking  this  integral  ;  always  neglecting  quantities  of  a  higher  order 
than  those  which  are  retained,  and  such  as  depend  on  different  angles. 

t  (2706)  Since  v  [3834]  contains  the  tenu  2  e .  sin.  {yit  -\-  s  —  ro),  it  is  evident  that 
the  variation  of  v,  corresponding  to  the  increments  Se,  <)■&,  in  e,  zs,  respectively,  is  as  in 
[4556];    and  by  using  the  symbol     JV:=nt-{-s  —  zs  [3702»],  it  becomes, 

8v=:2Se.  sin.  W — 2  e ô a  . cos.  W.  [4.557a] 

Now,  if  we  put,  for  brevity, 

VOL.  III.  81 


322  PERTURBATIONS  OF  THE  PLANETS  ;  [M^c.  Cél. 

which  gives  in  v  the  inequality, 


2  jn     ft  vt 


s  • 


It  follows,  from  §  65  of  the  second  book,  that  in  the  case  of    i.(n' — n)  +  2n 
[4557]     being  very  small,  the  expression  of  R,  relative  to  the  action  of  m  upon  m', 
contains  also  a  term,  of  the  following  form  and  value,  very  nearly,* 

[4558]  R  :^m.  M'".  e  e'.  cos. {i.(n't  —  ?t  ^  +  s'—  e)  +  2  n  ;  +  2  s  —  w  —  ^^'1  ; 

since,  by  noticing  only  the  two  terms  of  this  kind,  in    R,  and    R,    we  have, 
as  in  [1202],  very  nearly. 


[45576]         T,^i.{n't  —  nt-\-^—i)+^nt-\-2-=  —  zs  —  zi';  M,=^      '"'"   — .M'\e': 

i.(n — n)-|-2n 

the  expressions  [4553,  4554]  become, 
[4557c]  (5e  =  — ^j.cos.T,;  e  <5  w  =  —  Ji,  .sin.T,  ; 

substituting  these  in  [4557a] ,  we  get, 

[4557rf)  èv  =  2  Jlii. { —  cos.Tj.  sin.  JV -{-  sin-Tj .  cos.  W\  =  2  JW,.  sin.(Ti—  JF) 

=  2  iVii-  sin.  { i.{n't  —  nt-\-  s' —  s)  +  «  t  -\-  s  —  ra' | 
[455re]  ^2M,.sm.\{i~l).{n't  —  nt  +  s'—E)Jf-n't+i'-u'\,  as  in  [4557]. 

*  (2707)     Using  the  symbol  Tj  [45576],  we  get,  from  [4552], 
[4558a]  B.  =  ni.  JW">.  e  e' .  cos.  Ti . 

Its  differential,  relative  to   d  [37056 — c],  is, 

[45586]  à.R  =  rri.  M^^\  e  e'.  (i  —  2) .  n  dt .  sin.  Ti  ; 

substituting  this  in  the   differential  of   [4559],  which  gives      m'.  d'iî'=:  —  7n.AR,     and 
dividing  by   m',  we  obtain, 

[4558c]  d'iî'=  —  m  .  M'-^K  e  e'.(i —2)  .  n  dt .  sin.  Tj . 

Now,    i.{n' — n)-\-2n,    being  very  small  [4557'],  we  have,  very  nearly, 

[4558rf]  {i—2).ndt=^in'dt; 

hence, 
[4558e]  à'R=  —  m.  iVi">.  e  e'.  in'dt.  sin.  Tj . 

Integrating  this,   relative  to  the   characteristic    d',    which  does  not  affect  n  t  r3982al,   we 

[4.5.58/]         ,  r^rron 

•■       ■'  ^     obtam,  as  m  [4558], 

[4558g-]  ^'=  "*  •  -^^"'-  ^  ^'-  COS.  Tj . 


VI.xv.§40.J  VERIFICATION  OF  SEVERAL  INEQUALITIES.  323 

m.fàR+  m'.fd'  i?'=  0  ;  [4559] 

therefore  we  have,  in  v',   the  inequality,* 

S  v'=  .,!"''"'!''     -ili'".  e  .  sm.l(i—l).(n't  —  7it -{- i' —  s)  +  nt  4-s  —  7,\.  [4560] 

t.{n' — «)  +  2n  (  V  /  \ 

These  two  inequalities  of  v  and  v'  [4557,4560],  are  in  the  ratio  of  m'.e'.\/a'     [4560] 

to  ?ft.e.y/«  ;  so  that  the  second  may  be  deduced  from  the  first,  by  multiplying 

the  coefficient  of  the  first  by     "1;}^^^    [4660«-].  ^4560"] 

•^       ?»'.\/«  e'     *-  '^ 

The   quantity      5n" — 3  n'    being    small,  in  comparison  with    n'   or    n", 
we  have,  in  v'  [4557],  by  supposing    i  ^  5,  an  inequality  depending  on  the 
argument    5  n"  ^  —  4  n'  t  +  5  s"—  4  /—  ^"  ;     and  in    v"  [4560] ,  an  inequality    [4560'"] 
depending  on    the  argument    4n"i — 3n't  +  ^s" — 3s' — -a'.      The   first  of 
these  inequalities  is,  by  [4291], 

6  v'  =  2^,196527  .sin.  (5  n"t  —  ^n't  +  b  f—  4  ^'—  ^")-  [45Ci] 

Multiplying  its  coefficient   by        /    „ .  -,      we    have,    for    the    earth,    the    ve"j 

"*  V*^        ^  thcEarlh. 

inequality, 

iv"=0\6580.sm.(^n"t  —  3n't-\-4^i"  —  3e—zs').  [4562] 

By  a  direct  calculation,  we  have  found,  in  [4307],  this  inequality  to  be, 

Ô  v"  =  0',722424  .  sin.  (4  n"  t  —  3n't  +  4^s"  —  3e'  —  ^');  [4563] 

which  differs  but  little  from  the  preceding. 

*  (2708)     We   may  obtain    ô  v'  from  R',  by  a  similar  process  to  that  used  in  the  two 
preceding   notes  ;    or,   more   simply,    by    derivation,   in    tlie   following    manner.      If    we     [45600] 
change,  in  [4552],  i,  m,  a,  n,  e,  v,  &ic.  into  — i-\-2,  m',  a',  n',  e',  v'  he.  respectively, 
without  altering  Jlf"',  R  changes  into  R  [4558a,^],  and  the  factor  r.(»i' — ti)-\-2n,  becomes, 

(— '  +  2).(m  — 7«')  +  2n';  [45606] 

which,  by  reduction,  is  easily  reduced  to  its  original  form  ;  so  that  the  angle  T,  [45576] 
remains  unaltered.     The  factor  M^  [45576],  changes  into 

^^-d^^^n-^'"''-^-^  [«60c] 

W  changes  into  W  [.3726a];  and  the  second  expression  of  5  d  [4557 </],  becomes  as  in 
the  first  of  the  following  expressions  of  lî  v',  which,  by  successive  operations,  is  reduced  to 
the  form  [4560e],  as  in  [4560]  ; 


324  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

In  like  manner,  4  n"'  —  2  n"  is  rather  small,  in  comparison  with  n" 
or  n'"  [4076/i]  ;  and  if  we  suppose  i  =  4,  we  obtain  in  v"  [4557],  an 
inequality  depending  on  the  argument 

4 w"'i  —  3  n"t  +  4  s'"  —  3  s"  —  ^"'  ; 
[4564]      and  in  v"'  [4560],  an  inequality  depending  on  the  argument 

Sn"'t  —  Inl't  +  3  £'"—  2 e"—  ra". 
The  first  of  these  inequalities  is,  by  [4307], 
^45g5^  &  v"  =  OS8071 1 1  .  sin.  (4  n"'t  —  3  n"  t  +  4  e'"  —  3  -="—  ^"'). 

m"\/a"    e" 
Multiplying   its  coefficient  by        ,„   ,—  .  —     [4560"],  we  get,  for  Mars,  the 

The  Ea- til  1    J       to  J  m     \/ o!       t 

and  *^ 

*'^"        inequality, 

[4566]  ^  «'"  =  0',661446  .  sin.  (3  n'"  ^  —  2  ?î"/  +  3  £'"  —  2  e"  —  ^")  ; 

and  by  direct  calculation  we  have,  in  [4375], 

[4567]  <s  v'"  =  0', 846004  .  sin.  (3  n'"  i  —  2  n"  «  +  3 .'"  —  2  e"  —  i.")  ; 

the  difference  is  within  the  limits  of  the  error  which  may  be  supposed  to 
[45681      exist,  taking  into  consideration,  that  the  ratio    4  ?i"' — 2  m"   to    n'",  instead 
of  being  very  small,  is  nearly  equal  to  |. 

41.  It  also  follows,  from  §  71,  of  the  second  book,  that  if  i.{n' — n)+2  n 
[4569]      ^^  ^''^^'2/  s»«a//  in  comparison  with  n',  the  inequality  of  m,  in  latitude,  depending 

on  (i  —  \).{n't — nt-{-s — s) -{- n' t -\- s' ,  is  to  the  inequality  of  m',  in 
[45<39']     latitude,  depending   on     (i  —  \).{n't  —  nt^s  —  i)-{-nt  +  i,     in   the  ratio 

of    m!  \/a'    to    — m\/a.* 

[4560(i]    'î  d'  =  2  Ma .  sin.  (Tj  —  W)  =  2  .¥o  .  sin.  \  i.{n't  —  n  <  +  e'—  s)  +  2  «  i  +  2  £  —  n't  —  s'-  ra  ? 
r4.5<jOel  "^^  2^2  •  sin.{(i  —  \).{n'  t  —  nt-\-i' — i)  -\-  nt-\-  s  —  la^. 

Dividing  the  value  of  ^v'  [4560]  by  that  of  &v  [4557],  we  get,  successively,  by  using 
^"^^^^■f^     an  =  a-i,     a'n'=  «'-*  [3709'], 

i5«'        m.a'n' e  m.a'~i  e         m.ai    e  ■     r^rz-^wn 

In  applying  this  formula  to  numbers,  we  must  vary  the  accents  in  the  elements,  so  as  to 
conform  to  the  notation  used  in  this  book,  as  is  done  in  [4560"',  &;c.]. 

[4569a]  *  (2709)  The  inequality  of  s,  here  referred  to,  is  given  in  [1342]  ;  that  of  s',  depending 


VI.  XV.  §41.]  VERIFICATION  OF  SEVERAL  INEQUALITIES.  325 


If  we  suppose  i  =  5,  we  shall  have,  in  the  motion  of  Venus  in  latitude     venu» 
[4569o-,  4295],  the  inequality  [4295],  thlEani.. 

ôs'  =  —  0',312535 .  sin.  (5  n"t  —  4  n't  +  ôi"—4>e'—è').  [4570] 

Multiplying  the  coefficient  of  this  inequality  by ■;yy^  [4569'],  we  get, 

in  the  motion  of  the  earth  in  latitude,  the  inequality  [4569/], 

&  s"  =  0',22869 1 .  sin.  (4  n"  i  —  3  n'  Ï  +  4  s"  —  3  s'  —  0  ;  f"*^^^ ^ 

and,  by  direct  calculation,  we  have  found,  in  [4312],  the  inequality, 

6  s"  =  0S234256  .  sin.  (4  n"t  —  3  ti'  Ï+4  s"—  3  s'—  6')  ;  [4572] 

which  differs  but  little  from  the  preceding. 


on  the  same  angle,  is  similar,  the  accents  being  changed  so  as  to  adapt  them  to  the  value  of 
s'.  Instead  of  this  formula,  we  may  use  [4295J],  observing  that  the  second  line  of  this 
expression  is  used  in  computing   the   inequalities  which  are  taken   into  consideration  in     ^  ' 

[4569 — 4576].      The  expression  of    5  s,    deduced  from   this   part  of    [4295i],  may  be 
simplified;    because   the  divisor    n^ — \n — i.{n  —  «')P'     '^^'^Y   ^^  reduced  to  the  form    [45G9c] 
(' .  ()i  —  «')  .\i  .[n'  —  n)  -\-  2  n] .     Hence  this  part  of  i5 s  becomes, 

_B(.-i) 
6s=im'.n^.a^a'.  -^ tttT-: --r-r.y  .sin.  h'.(»i' i  —  ?i  i  +  s'— s)  +  n  <+ s  —  nj  ;       [45G9d] 

7  being  the  inclination,  and   II    the  longitude  of  the  ascending  node  of  m',  upon  the  orbit 

of  m.     This  expression  may  be  simplified,  from  the  circumstance,  that,  in  the  terms  here    [4569e] 

taken  into  consideration,  the  divisor    i.{n  —  n')    is   very  nearly  equal  to      2n      [4569]. 

Substituting  this,  and    ?irt^=l,    in    [45^9 (Z]  ;    making   also    a   slight    reduction    in    the    ["^^'^^l 
arrangement  of  tlie  terms  depending  on    i,  we  get, 

ôs=+im'.^a'.{aa')i  (■_l)_(j!^^"^^>^,^ -7  •sin-K''-l)-K^- ^^  i  +  s'-s)-\- n't  +  b'-UI    [4569g:] 

Changing  the   elements      ?«,    a,    n,    s,    U,  &c.    into    m,    a',    n',    s',    n  +  180'^.    Sic.    M,-pq.-i 
respectively,  and  altering  the  sign  of    i — 1,    which  does  not  affect    2i"~''    [956,956'], 
we  get, 

5  s'=—  my  a  .{act')  .  rr—rr:-, -—, •  7  .sin.U?:— l).(?l'^—  «  ?  + /—  e)  +  ?i  C  +  £  — H^      [4569i] 

Hence  we  evidently  perceive,  that    S  s  is  to  as'  as  m'\/a'  to  — m\/a,  as  in  [4569'].  [4569A;] 

Now,  the  values    n',    n"  [407 6A]  make   5  n" —  3  ?i'   quite  small,  in  comparison  with  ?i'. 
This  corresponds  with  the  value  assumed  for    i.{n' — 7))-{-2n   [4569],  supposing    i  =  5  ;     [45G9i] 
hence  we    get    [4.570 — 4572].     In  like  manner,    3  ?i'' — n"  [4076A],    is  very  small,  in 

VOL.  III.  82 


326  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

[4573]         The  quantity     3  n"  —  if    is  small  in  comparison  with     n"'  ;     therefore, 
[4573]     by  making  i  =:  3  [456%,  z],  we  obtain  in  ôs",  an  inequality  depending  on 

3  n''t  —  2  7f  t  -{-  S  s'''  —  2  i"  ; 

and  in    6  5",  an  inequality  depending  on 

2n''H  —  n''t  +  2!''  —  s\ 

The  first  of  these  inequalities  is,  by  [4511], 
[4574]  6  s"  =  0',662991  .  sin.  (3  n^'t  —  2  n^t  +  3  s"'—  2 1^  —  n'''). 

n"'    being  the  longitude  of  the  ascending  node  of  the  orbit  of  Uranus  upon 

[4574']     that  of  Saturn.     Multiplying  the  coefficient  of  this  inequality  by -^y—  , 

and        we  obtain  in  ôs"',  the  inequality, 

Uranus.  '  ^  J  ' 

[4575]  65"=  — 2'',714213.  sin.  (2ra'"^  — w^^ +  2£^'— s"— n^'); 

and    by    [4531],    this    inequality    becomes,    by    putting     n^  =  n"' + 1 80'' 
[4531',  4574'], 

[4576]  is''  =  —  2',921052  .  sin.  (2  n^'t  —  nU  +  2 1"'—  e"  —  n^')  ; 

which  differs  but  little  from  the  preceding. 

42.     It    follows,    from   §  69,  of  the    second  book,   that  if   we   suppose 
[4576']     i'  n'  —  in   to  be  very  small  relatively  to  n  and  n',  and  represent  by,* 

[4577]     R  =3r  m'.P.  sin.(i'n't  —  int  +  i'e'—is)-}-m'.P'.cos.(i'n't—int  +  i's'—is), 

the  part  of  the  development  of    R,    depending  on  the  angle 

i'n't  —  i  nt-\-  i's' —  i  s  ; 
it  will  produce,  in   6v,   the  inequality, 

..-„„   ,    comparison  with    ?r  or  n"' ;    and  this  comes  under  the  form  [4569],  by  putting    f  =  3; 
hence  we  get  [4574—4576]  ;  observing  in  [4576],  that    n^  =  n"  +  180<f. 

*  (2710)    Using  the  value   Tg  =  i'n' t  —  i  nt +  i'^ —  i  s  [4019a],  and  (j,  =  1  [3709] , 
we  find  that  the  tenns  of  i2,  Se,  eSzs,  which  correspond  to  each  other  in  [1287,1288,1297], 
become, 
[45776]  -R  =  "*'•  P-  sin-  ^9  +  '">''•  P-  c°s-  ^9 ; 

14577c]  ,  e  =  "^4^  .  5  _  (^) .  Sin.  T,-  (f)  .  cos.  T,  \  ; 

m—m    (        \de J  \de  J  ) 


2  m. an       ,        ,      .  . 

^V=rr-r-r7.-<        ,  h  [4578] 


Vl.xv.H2J  VERIFICATION  OF  SEVERAL  INEQUALITIES.  S27 

—  ( — V  COS.  {i'n'  t  —  int-\-i'  ^ — is — nt  —  s  +  ra) 

and  in     6  v',    the  inequality,* 

,   ,    ( — ( -—A  . COS.  (i' n' t  —  int4-i's'  —  is  —  n't — s'  +  ra') 
,       2m.  an'     \       \de'J  ^  ^  '       \ 

6v'^  T-; '  ^  ,  >.  [4579] 

^^"  =  ^$S.  •  1  O  •^°^-  ^«-  (S)  •  ^'"-  ^^  1  •  f4577d] 

Substituting    these    in     8v    [4556],  using  for  brevity,    W=znt-\-s  —  w    [3702a],   and 
reducing,  by  [22,  24]  Int.  we  get,  as  in  [4578], 

„    ,  (— ("— Vrsin.Tg.sin.fF+cos.rg-cos.fF), 

tn-in      }_|./^V(sii,.2'9.C0S.fr— C0S.r9.sin.fF)< 

2m'. an    (        /dP\  ,_,         „^,    ,    /dP'\      .      ,^         „n  > 

*  (2711)     Proceeding   in  the  same  manner  as  in  [4558a — c],  and  using    Tg  [4577a], 

we  have, 

àTg=  —  indt,  à'T^==i'n'dt;  [4578a] 

hence  the  differential  of  It    [45776],  relative  to  the  characteristic    d,    becomes, 

dK  =  — m'.in.{P.cos.T9  — P'.sin.rg^  [45786] 

Substituting  this  in    m'.à'R'=  —  m.dR    [4558i — c],  we  get, 

d'  «'  =  m .  i  n  .  { P.  cos.  Tg  —  P'.  sin.  Tg } .  [4578c] 

Integrating  this,  relatively  to  d',  and  observing  that  the  divisor  i'n'  is,  by  hypothesis, 
very  nearly  equal  to  in  [4576'],  we  get,  for  the  corresponding  terms  of  R',  depending 
on  the  angle    Tg,    the  following  expression  ; 

R'  =  m.{P.  sin.Tg  +  F. cos. Tg].  [4578rf] 

From  this  value  of  R'   we  may  compute    5  v',    in  the  same  manner  as  we  have  found    S  v 

[4578],  from    R  [45776].     It  will,  however,  be  rather  more  simple  to  use  the  principle  of    [4578e] 

derivation,  by  observing,  that  if  we  take  the  differential  coefficient  of  R    [4577è],  relative 

to    e,    multiply  it  by    2andt,    then  take  its  hitegral  relative  to     t,    and  change     Tg    into 

Tg  —  W,    it  will  become  equal  to  S  v  [4577e].     In  like  manner,  if  we  take  the  differential    Mgyg^-, 

coefficient  of  JÎ'  [4578rf],  relative  to  e',    multiply  it  by    2a!n'dt,  take  its  integral  relative 


328  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

It    follows  also,    from  ^71,  book  ii.  that    the  same   terms  of    R    [4577] 
produce,  in    6  s,    the  inequality,* 


[4580]  5  s  =  .—. : 


' — ^  .cos  .(i'n't—  i  u  t4-  i'  s'  —  i  I  — n  t  —  e-|-  n)  ) 
—  (--\  .  sin.  (i'  7i't  —  int-^i's'  —  is  —  nt  —  s  +  n)  \ 


y    being  the  tangent  of  the  respective  inclinations  of  the  orbits  of   m  and  m', 
[4580']     and    n    the  longitude  of  the  ascending  node  of  the  orbit  of  m'    upon  that 
of   m  [42956— c]. 

If    we    increase   the    argument    of    the    inequality  of    6  v    [4578],     by 

[4580"]     nt  -{-  s  —  ra,     and  multiply  its    coefficient    by    e  ;    also,  if  we  increase  the 

argument  of  the  inequality  of    6v'    [4579],  by     n't  +  s' — ■us',     and  multiply 

[45811      its  coefficient  by     — ^-— .  e'  ;t     lastly,  if  we  increase  the  argument  of  the 

■■  ■'      m  \/a  "^ 

inequality  of    6  s    [4580],  by    nt-\-i  —  n,    and  multiply   its   coefficient  by 
—  2-/,    the  sum  of  these  three  inequalities  will  be. 


[4582] 


Qm'.an 


'+^•(f)+«■•(")+^Q^™'■<'■■»■'-'•»'+^"■-")l 


to  t,  and  afterwards  change  Tg  into  Tg — TV  [.3726a],  it  will  produce  the  following 
expression  of    &  v',    which  is  equivalent  to  [4579]  ; 

l"»^l  *"'=l5^  h  (©  ■  »■  (''.-"'■)  +  Q  •  ''■•■  (T,-rr)f 

*  (2712)     If  we  put,  for  brevity,    T.2  —  i'n't  —  int-{'A—gè;,     also    7  =  tang,  ip/ 
[4580a]     ["1337'^  3739]  .    the    assumed    value    of   R    [1337"]    becomes,       R  =  m'.k  .jK  cqs.%. 

[45806]     Substituting  this  in  the  expression  — fi  —  ] .  andi,     we  find  that  it  becomes  equal  to  the 

expression  of  s  or  5  s  [1342]  ;  provided  the  angle  T,  be  decreased,  after  the  integration, 
by  the  quantity  v  —  Ô/,  or  by  the  angular  distance  of  the  body  m  from  the  ascending  node 
of  the  orbit  of  λ'  upon  that  of  ?«  [1.337'].  In  the  present  notation  v — 0/  is  represented 
by  the  quantity  nt-\-s — n,  neglecting  terms  of  the  order  e  [429.5i — c].  The  same 
process  being  performed  upon  the  assumed  value  of  R  [4577],  produces  the  expression  of 
6s  [4580]. 

[4581a]         t  (2713)     This  factor  is  equal  to     ^^^'-.«'[4560/]. 


VI.  XV.  §42.]  VERIFICATION  OF  SEVERAL  INEQUALITIES.  329 

Now,  P  and  P'  are  homogeneous  functions  of  e,  e',  7,  of  the  dimension 
i' —  i,  and  i'  is  supposed  greater  than  i  ;  therefore  the  preceding  function 
is  equal  to,* 

'2m!.an.{i'—i)  ^ ^_p  ^^^(■^^,f_ j-,j^_)_^v^.,_  •  ^^  _^p,_  sin. {i'n't—int+i's'—i 0 1 .       [4583] 
Now  we  have,  in    àv,  the  inequality,  [1304], 

'^'^—  p""^ — ^  •  S  -f*-  ^°^-  (*'"'^  —  î'ni-f  iV — i  £) — P'.  sin.  (iV/ — int+i's' — is)  \  ;     [4584] 
hence  it  follows,  that  if  we  represent  by 

6v  =  K.  sin.  (i'  n't  —  i nt-\-i'  i'—iB  —  nt  —  i-\-  O),  [4585] 

the  inequality  of  6  v,  depending  on  the  angle   i'n't — in  t  +  i'^'  —  i  s — n  t — £  ; 

and  by 

5 v'  =  K'.  sin.  {i' n' t  —  int  +  i  s'  —  z  ;  —  n' t  —  s'+  O), 

the  inequality  of  &v',  depending  on  the  angle  i'n't — int-\-i'i' — z's  —  71' t —  s';     [4586] 
lastly,  if  we  represent  by 

6s  =  K".  sin. (i! n't  —  int-^i' s  —  z s  —  nt  —  e  +  0"),  [4587] 

the  inequality  of  à  s,  depending  on  the  angle  i'n't  — i  nt  +  i's'  —  is  —  nt  —  s, 

we  shall  have,t 

Ke  .  sin.  (i'  n't  —  int  -{-  i' i —  is  —  « -f-  O) 

+  '^'.  K'  e'.  sin.  (i'  n'  t  —  int  +  i'  s'  —  is—  ^'+  O') 

—2  K"  7 .  sin.  (i'  n't  —  int  +  i's'  —  is  —  n-{-  O")  ^''^^^^ 

=  _  U^Illl.H.  ^''"'~"'^  .  sin.  (if  n't  —  i  nt  +  i'  s'  —  is  +  Q); 

*  (2714)     From  [957'"]   it  appears,  that  any  part  of   B,    depending  on  angles  of  the 
form     i'n't  —  int,      must   be  composed  of  terms   in     e,    e',    7,     of  the  orders     i' — i,    ^        ^^ 
i' — Ï  +  2,    &IC.  ;     and  by  neglecting  all,  except  the  first,  on  account  of  their  smallness,  they 
must  be  of  the  order    i' — i;     and  therefore  homogeneous  in  these  quantities.     Now,  if  we    r-rpoii 
put,  in  [1001a],    a  =  e,     «'=  e',     a"=y,     m  =  i' — i,    and  then,  successively,  .^''':=  P, 
d^')=  P',     we  get, 

«•(f)+''-(S)+-(f)=P-^)- 

Substituting  these  in  [4582],  we  obtam  [4583]. 

t  (2715)     The  first  member  of  [4588]  is  equal  to  the  sum  of  the  inequalities    ôv,     èv', 
VOL,  III.  83 


330  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

[4588'] 


n 


IS 


6v  =  H.  sin.  (i'  n'  t  —  i  n  t  -\-  i'  s'  —  i  «  +  Q)      being    the    inequality    of     6  v 
depending  on  the  angle    i'  n'  t  —  int  +  i'  s  —  i^ . 

The  quantity    5  n' —  2  n    [4076/i]  is  very  small  in  comparison  with 
^'^^^^"^    and  we  have,  in    àv    [4282],  the  inequality, 

[4589]  àv  =  l %690443  .  sin. (5  n' <  —  3 n i  +  5  s'  —  3 s  +  43"  1 8 "■  32'). 

^,^^^^^,      The    inequality     6 s    [4283'],    depending  on    5n't  —  3nt  +  ôs'  —  3e, 
Venus.       insensible;  and  we  have,  in    6v'  [4293] ,  the  inequality, 

[4590]  Sv'  =  —  0',333596  .  sin.  (  4  n' <  —  2  n/  +  4  s'  —  2  ^  —  39'  30'"  30'). 

Lastly,  we  have,  in    ô  v    [4283],  the  inequality, 

[4591]  6t)=  8',483765  .  sin.  (.5  n't  —  2nt  +  5.-'  — 2.-  — 30"  1 3- 36'). 

In  this  case    ?''=  5,     i  =  2  [4584,4591];  and  we  have,  by  what  precedes 
[4585 — 4591],  the  following  equation  of  condition; 

r,690i43. e  . sin.  (5  n' t  —  2nt  +  5  s'  —  2  i  —^  +  4^3'  18'" 32') 

[4592]  —  0',333596.e'. -"'^.sin.(5n'i  — 2ni  +  5£'  — 2s_^'_39''30'"300 

=  _  8',483765  .  ■^"'"'^"^.  sin.  (5  n7  —  2  n^  +  5  /  —  2  .  —  30"  13"'  360- 

71 

The  first  member  of  this  equation  is,* 
[4593]  0%359753  .  sin.  (5  n'  i  —  2  w  i  -f-  5  e'  —  2  s  —  28"  27""  33')  ; 

the  second  member  is, 
[4594]  0',3605  .  sin.  (ôn't  —  2nt  +  ô  s'—  2  s  —  30"  13'"  36')  ; 

and  their  difference  is  insensible. 


Ss,      [4585,4586,45871;    multiplied  respectively  by     e,      — - — .  e',    and    — 2y;     the 
[4588a]  '»•« 

arguments  being  also  increased  by  nt-\-s  —  w,  n't-^e' — ts',  nt-\-s  —  IT,  respectively, 
according  to  the  directions  in  [4530"— 4531].  Now,  it  is  shown,  in  [4530"~4583J,  that  this 
sum  is  equal  to  the  expression  [458.3],  which  is  the  same  as  that  of   &v    [4584],  multiphed 

by — —  .  (  )  ;     and  if  we  suppose  this  expression  of    Sv    to  be  reduced  to  the 

[45886]  '^^        \     "      / 

form  [4588'],  this  product  will  be  represented  by  the  second  member  of  [4588]. 

*  (2716)     This    is  easily  olrtained,  by    reducing  the    two  terms  of   the    first    member 
[4593a]    of   [4592]    into  one,  by  the    method   [4282/t — /],  after  substituting    the    values     m,    m', 
a,    a',  he.    [4001,4079,4080]. 


VI. XV. §43.]  VERIFICATION  OF  SEVERAL  INEQUALITIES.  331 

We  may  verify,  by  the  preceding  theorems,  many  of  the  corresponding 
inequalities  of  Jupiter  and  Saturn  ;  but  as  all  the  inequalities  of  these  two     [4594'] 
planets    have   been   verified    several    times,  with    much    care,  by    different 
computers,  this  last  verification  is  unnecessary. 

43.     The  inequality  of    m,  produced  by  the  action  of    m',  and  depending 
on  the  argument    n'  t  +  -'  —  ^'j    is  expressed  as  in  book  ii.  ^  50,  55,  by,* 

à  V  =  ^-^ — -  .  (0,1)  .  e'.  sin.  (n'  t  +  i' —  «')•  [4595] 

The  inequality  of  ?«',  produced  by  the  action  of  m,  and  depending  on  the 
argument    nt-\-£  —  ct,    is, 

6  v'  =  "  .  (1 ,0)  .  e .  sin.  (Jl  /  +  e  —  ra).  [4596] 

n.{n- — n-')     ^       '  ^ 


[4596'] 


The  coefficients  of  these  two  inequalities  are,  therefore,  in  the  ratio  of 
—  (0,1)  .  7i\  e'    to    (\,0).n'\  e;     now  we  have,  in  [1093], 

therefore,  if  we  put  Q  for  the  coefficient  of  the  inequality  6  v  [4595], 
we  shall  find,  that  the  coefficient  of  the  inequality  ôv'  [4596],  will  be 
represented  by, 

f^.î.Q     [4595/].  [4598] 


m.  a ■'      e 


*  (2717)     The  term  of  5  ti  depending  on    n't-{-s' — zs',    is  deduced  from  that  in  [1021], 
depending  on    G'',  by  putting    i  :=  1  ;    whence  we  obtain, 

Sv='^  .  G<".  e'.  sin.  {71'  t  +  s'—  ^'}.  [4595„] 

Now,  from  [1018, 1019, 1073],  we  have,  in  the  case  of    i=l, 

^"=-«H-^)-*«H7^)=™r„-(«'')=  [45956] 

G-^-,£^..^-==-„7:(^)-(0.1)-  [4595.] 

Substituting  this  value  of   G<'\  in   5v  [4.595rt],  it  becomes  as  in  [4595].     The  value  of  Sv' 
[4596]  may  be  directly  computed  in  a  similar  manner  ;  or  it  may  be  obtained  more  simply  by 
derivation  from  [4595]  ;  changing     to,     a,     n,     e,    he.  into    m',     a',     n',     e,    &lc.  ;  and    [4595rf] 
the  contrary  ;  observing,  that  by  these  changes,    (0,1)    becomes    (1,0),    according  to  the 


332  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

The  inequalities  of  this  kind  have  been  verified,  either  by  means  of  this 
equation  of  condition,  or  by  that  of  the  preceding  expression  of  Q.  Thus, 
the  action  of  Jupiter  produces,  in  the  earth,  the  sensible  inequality  [4307], 

[4599]  6  v"=  — 2',539884 .  sin.  (n"  t  +  s"—  ^"). 

This  inequality,  by  what  precedes,  is  represented  by  [4595], 

[4600]  6  v"=  ^^,^^.,_^..,^ .  (2,4)  .  e\  sin.  (n- 1  +  a--  «-)  ; 

TheEarth    ^^d  wc  havc    (2,4)  =6^947861   [4233].     If  we  substitute  this,  in  [4600], 
juiuer.      also  the  values  of    n",    tf\    é"    [4077,  4080]  ;  then  multiply  the  result  by 
the  expression  of  the  radius  in  seconds,  we  shall  obtain, 

[4601]  âî)"  =  — 2'-,5401.sin.(?i'-'/;  +  e"'— ra'^). 

The  action  of  Uranus  upon  Saturn,  produces,  in  the  motion  of  Saturn,  the 
inequality    [4466] , 

[4602]  5 î;v  ^  _  p^oil647  .  sin.  {itH  +  i"—  :='')• 


Saturn 

and 

Uranus 


„v    „vo        pV 


Multiplying  its  coefficient  by ^v73"'  Ti    [4'598],  we  obtain,  in  Uranus, 

the  inequality, 

[4603]  5z;'i=0%214852.  sin.  (m'^  +  s'  — ^')  ; 

and  the  direct  calculation  has  given,  in  [4525], 

[4604]  à  v"'  =  0',2 14857  .  sin.  (nU  +  i"—  ^'). 

notation  in  [1085,  &;c.].     Comparing  the  values  of   o  v,     &  v'    [4595, 4596] ,  we  get  the  first 
[4595e]    expression  of  [4595/]  ;  and  by  substituting  the  value  of  (1,0)    [4597];    also     n^=zcri, 

_9 

n'^=a'  ^   [-3709'],  we  get  successively  the  last  expression  [4595/],  which  is  equivalent 
to  [4598]; 

.    ,  (1,0)    n'^e     .  m\/a     n'^e  m .  a^     e 

rdw^n  à v= • . .01)  = ; — , •  —r-, .ov  =  —  -— — r- .  -,  .ov. 

L^^^^.'J  (0,1)    Ji3e'  viVa'     n3e'  m'.a'^     e' 

[4600o]        *  (2718)     The  expression  [4600]  is  similar  to  [4595],  changing   m,    m',  &ic.  into   m", 
m'",   Stc. 


Vl.x%'i.  5,41.]   ON  THE  MASSES  OF  THE  PLANETS  AND  MOON.         333 


CHAPTER    XVI. 


OiN  THE  MASSES  OF  THE  PLANETS  AND  MOON. 


[4604] 


44.  One  of  the  most  important  objects  in  the  theory  of  the  planets  is  the 
determination  of  their  masses  ;  and  we  have  pointed  out,  in  [4062 — 4076'], 
the  imperfections  of  our  present  estimation  of  these  values.  The  most  sure 
method  of  obtaining  a  more  accurate  result,  is  that  which  depends  on  the 
development  of  the  secular  inequalities  of  the  motions  of  the  planets  ;  but 
until  future  ages  shall  make  known  these  inequalities  with  greater  precision, 
we  may  use  the  periodical  inequalities,  deduced  from  a  great  number  of 
observations.  For  this  purpose,  Delambre  has  discussed  the  numerous 
observations  of  the  sun,  by  Bradley  and  Maskelyne  ;  from  which  he  has 
obtained  the  maximum  of  the  inequalities  produced  by  the  actions  of  Venus,  [4604"] 
Mars  and  the  moon.  The  whole  collection  of  these  observations  of  Bradley 
and  Maskelyne,  makes  the  maximum  of  the  action  of  Venus  greater  than 
that  which  corresponds  to  the  mass  we  have  assumed  for  Venus  [4061],  in 
the  ratio  of  1,0743  to  1  ;  hence  the  mass  of  Venus  is  ■gyVe^-aa  of  that  of  [4605] 
the  sun.     The  observations  of  Bradley  and  Maskelyne,  when  we  take  them      Mass  or 

Venue. 

separately  into  consideration,  give  nearly  the  same  results  ;  therefore,  it  is 
probable,  that  this  estimate  of  the  mass  of  Venus  is  not  liable  to  an  error  of 
a  fifteenth  part  of  its  value.  [460.5'] 

Hence    it    follows,  incontestably,   that    the    secular   diminution    of    the 
obliquity  of  the  ecliptic  approaches  very  near  to  154"=49',9.     To  reduce 
it,  as  some  astronomers  have  done,  to  105"=  34%    we  must  decrease  the      [4606] 
mass  of  Venus    one  half;*    and  this    is  evidently  incompatible  with    the     [4606] 


[4604" 


*  (2719)     This  appears,  by  substituting     q"=  —  M',     t  =  \00  [4606],  in  [4074c]; 
whence  we  get,  very  nearly,   — .34'=  — 50' — 31V' j     consequently,    i>-'= — h,   nearly. 

VOL.  III.  84 


[4606o] 


334  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

observations  of  the  periodical  inequalities,  produced  by  Venus,  in  the  motion 

[4606"]     of  the  earth.      The  best  modern  observations  of  the  obliquity  of  the  ecliptic 

are  too  near  to  each  other,  to  determine  this  element  with  accuracy.     The 

observations  of  the  Arabs  appear  to  have  been  taken  with  much  care.     They 

[4607]      made  no  alteration  in  the  system  of  Ptolemy  ;  but  directed  their  attention 

particularly  to  the  perfection  of  the  instruments,  and  to  the  accuracy  of  their 

observations.     These  observations  give  a  secular  diminution  of  the  obliquity 

r.„«-„     of   the    ecliptic,    which  differs  but  very  little    from     154"^49%9.       This 

[460/  ]         ....  . 

diminution  is  also  confirmed  by  the  observations  of  Cocheouking,  made  in 
China,  by  means  of  a  high  gnomon  ;  and  it  appears  to  me,  that  these 
observations  may  be  relied  upon  for  their  accuracy. 

Delambre  has  also  determined,  by  a  great  number  of  observations,  the 

[4607"]     maximum    of  the  action  of  Mars  upon  the  motion  of  the  earth.      He  has 

Mass  of      found  this  action  to  be  less  than  that  which  corresponds   to  the  mass  we 

have  assumed  for  Mars  [4061],  in    the   ratio   of  0,725  to  1  ;  making  the 

[4608]      mass  of  Mars    ^TTis-a^?    of  that   of  the  sun.      This  value  is  probably  not 

quite  so  accurate  as  that  of  the  mass  of  Venus,  because  its  effect  is  less  ; 

but,  as  the  data  [4076],  from  which  we  have  determined  the  mass  of  Mars, 

[4608]     in  [4075,  &c.],  are  very  hypothetical,  it  is  important  to  ascertain  the  error 

which   might  result  from    this  cause,  in    the  theory  of  the  sun's   apparent 

motion.       Now,    the    observations    of  Bradley    and    Maskelyne,    combined 

together,  or  taken  separately,  concur  in  indicating  a  diminution  in  the  mass 

of  Mars  ;  therefore,  we  shall  decrease  the  preceding  inequalities,  produced 

[4609]     by  Mars,  in  the  earth's  motion,  in  the  ratio  of  0,725  to  unity. 

These    changes,  in    the   masses   of  Venus   and  Mars,  produce    sensible 
alterations   in  the    secular  variations   of  the    elements  of  the  earth's  orbit. 
Longitude    We  find  the  longitude  of  the  earth's   perihelion  to  be  represented  by  the 
'p^ihe'Ln.    following  expression  ;* 
[4610]  Long,  perihelion  ©  =  ^"+  1 . 1  P,807719  +  t\  0',00008 16482  ; 

the  coefficient  of  the  equation  of  the  centre  of  the  earth's  orbit  is 
represented  by. 


*  (2720)     The  expression  [4610]  is    computed  as  in  [4331],  changing  the  masses  of 
[4610a]     Venus  and  Mars,  as  in  [4605—4608].     The  formulas  [4611,4612]  are  computed  in  hke 
manner  as  [4330,  4332],  respectively. 


VI.  xvi.  •§,  44.]      ON  THE  MASSES  OF  THE  PLANETS  AND  MOON.  335 

Coeff.  equat.  centre  ©  =  2^— ï.0',171793  —  ^-.0',0000068194.  [461 1] 

Lastly,  the  values  of  p"  and  (f  [4332],  become, 

p'=       t.  0'-,080543  +  f.  0',000023 1 1 34  ;  ^^^^2 

q"=  —  ^0%521142  +  i%  0',0000071196. 

Hence  it  follows,  from  [4074c,  461 3«],  that  the  secular  diminution  of  the 
obliquity  of  the  ecliptic,  in  this  century,  is  equal  to  52',1142.*  Using  these 
data,  we  find,  by  the  formulas  of  ^  31, f 

^^t.\  5b", 5921  +  3M 1 0 1 9  +  42556",2 .  sin.  {t .  1 55",5927  +  95°,0733) 
—  73530",8.  cos.  (i.99",  1 227)  — 1 7572",4.  sin.  {t .  43",0446) 

[4C14] 

=  t .  50%412  +  2H7"-  57^+  13788^2  .  sin.  {t .  50%412  +  85''33"'570 

—  2382.3-,98.cos.(^.32%l]58)— 5693%5.  sin.  (i.l3^9465)  ; 

tPixcilT 

.     —^v,     ,.... ^v..^     ,..        -. , ..y...^^     ,^.^.      ,     .^     ,^.^^j  """'-J 

[4615] 

+  5082",7.  cos  (^ .  43",0446)— 28463",6  .  sin.  (^  99",  1227) 

Corrected 

=  23''  28*"  17%9— 1191',2  —  5892',8.cos.  (i.50%412  +  85'* 33"  57^  o7'.r 

precessioii 

+  1646%8  .  cos.  (i.  13%9465)— 9222»-,2  .  sin.(/.32'-,1158);      JJJS 


P- 

tic  for  the 
year  (, 
ailer  the 


|'=  i  .155",5927  +  3°,11019  — 3°,11019  .cos.(ï.99",1227)  etocV 

1750. 

—  14282",3  .  sin.  (t .  43",0446) 

[4616] 

=  ï.ô0%4120  +  2'^47'"57^  — 2'*47'"57^cos.  (L32%1158) 
—  4627^5  .  sin.  (M3^9465)  ; 

pApparent"! 
L    orbit.    J 

V'=  26°,0796  — 3676",6  .^1— cos.  (< .  43",0446)  ^ 
—  10330",4.  sin.  {t.  99",  1227) 

[4617] 

=  23''28'"17%9— 119P,2.p— cos.(Ll3%9465)| 

—  334^,05  .  sin.  (^.32%1 158). 


*  (2721)     The   chief  term  of  the  value  of   q"    [4612]  is    —  i.0%521142,    and  by 
putting  <  ^100,  it  becomes  q"^ — 52',1142.    This  represents,  by  [4074a — c],  the  secular    [4613a] 
variation  of  the  obliquity  of  the  ecliptic,  corresponding  to  the  second  formula  [4612];  in  the 
original  work  it  is  printed  160",85=52',1154,  and  it  is  thus  quoted  in  [3380n]. 

t  (2722)     The  formulas  [4614 — 4618],  are  computed  in  precisely  the  same  manner  as 


336  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


The     increment    of     the    tropical    year,    counted    from     1750,    is,   then, 

Increment 

of  the        represented  by, 

[4618]  Increment  of  the  year  =  —  0'"'^000086354  .  { 1— cos.  (t .  13',9465)  I 

—  0''=^000442198  .  sm.(t .  32^1158). 

Hence  it  follows,  that,  at  the  time  of  HIpparchus,  the  tropical  year  icas 
[4618']     10^9528    sexagesimal  seconds  longer  than  in  1750.      The  obliquity  of  the 

ecliptic  was  then  greater  by  955%2168.  Lastly,  the  greater  axis  of  the  sun'' s 
[4618"]    orbit  coincided  with  the  line  of  equinoxes,  in  the  year  4089  before  our  era  ; 

it  tvas  perpendicular  to  that  line  in  1248. 

The   mass  of    the    moon   has    been  determined  by   the  observations  of 
the   tides    in   the   port    of  Brest  ;    and,    although   these    observations    are 

[4619]  far  from  being  so  complete  as  we  could  wish,  yet  they  give,  with 
considerable  precision,  the  ratio  of  the  action  of  the  moon,  to  that  of  the 
sun,  upon  the  tides  of  that  port.  But,  it  has  been  observed,  in  [2435 — 2437'], 
that  local  circumstances  may  have  a  very  sensible  influence  on  this  ratio,  and 
also  on  the  resulting  value  of  the  moon's  mass.  Several  methods  have  been 
pointed  out,  in  the  second  book,  to  ascertain  this  influence  ;  but  they  require 
very  exact  observations  of  the  tides.  The  observations  which  have  been  made 
at  Brest,  leave,  in  their  results,  such  a  degree  of  uncertainty,  as  makes  us  fear 
that  there  may  be  an  error  of  at  least  an  eighth  part,  in  the  value  of  the 
moon's  mass.     Indeed,  the  observations  of  the  equinoctial  and  solsticial  tides, 

^^'^^^^  seem  to  indicate,  that  the  action  of  the  moon  upon  these  tides  is  augmented 
one  tenth  part,  by  the  local  circumstances  of  the  port.      This  will  decrease, 

[4621]  '^y  one  tenth,  the  assumed  value  of  ihe  moon's  mass  ;  and,  in  fact,  it  appears, 
by  several  astronomical  phenomena,  that  the  assumed  value  [4321]  is  rather 
too  great. 

The  first  of  these  phenomena  is  the  lunar  equation,  in  the  tables  of  the 

[4692]     sun's  motion.     We  have  found,  in  [4324],  8',8298  for  the  coefficient  of  this 

inequality,  supposing  the  sun's    parallax  to  be    S^S     [4322].       It  will  be 

[4357— 4360,  4362],  ahering  the  masses  of  Venus   and  Mars,  as  in  [4605,4608].     We 
have  previously  spoken  of  this  change  of  the  masses  of  tliese  two  planets,  in   [3380rt,&;c.], 
[4614a]    ^^^  j^^^g  ^jg^  given  the  formulas  of  Poisson  and  Bessel  [3380p,y],  for  the  determination  of 
the  precession  and  the  obliquity  of  the  ecliptic. 


Vl.xvi.  §44.]      ON  THE  MASSES  OF  THE  PLANETS  AND  MOON.  337 

8',5767,*     if   the   sun's    parallax  be    8^56,    which    is    the  value    deduced     [4622'] 
from  the  lunar  theory,  as  will  be  seen  in  the  following  book.     Delambre  has 
determined  the  coefficient  of  this  lunar  equation,  by  the  comparison  of  a  very 
great  number  of  observations  of  the  moon,  and  has  found  it  equal  to    7',5.      [4623] 
If  we  adopt  this  value,  and  also  the  second  of  the    above   estimates  of  the 
sun's  parallax,  which  several  astronomers  have  deduced  from  the  last  transit    "lass. 
of  Venus  over  the  sun's  disc,  we  find  the  mass  of  the  moon  to  be  ^-i  ^   of     [4624] 
the  earth's  mass  [4622&]. 

The  second  astronomical  phenomenon  is  the  nutation  of  the  earth's  axis. 
We  have  found,  in  [3378a],  the  coefficient  of  the  inequality  of  the  nutation 
to  be  equal  to  10',0556;t  supposing  the  mass  of  the  moon,  divided  by  the  [4625] 
cube  of  its  mean  distance  from  the  earth,  to  be  equal  to  triple  the  mass 
of  the  sun,  divided  by  the  cube  of  the  mean  distance  of  the  earth  from  the 
sun  [2706].  This  makes  the  mass  of  the  moon  equal  to  ^i^^  of  the  earth's  [4626] 
mass  [4321].  Maskelyne  has  found,  by  the  comparison  of  all  Bradley's 
observations  on  the  nutation,  that  the  coefficient  of  this  inequality  is  equal 


*  (2723)     The  coefficient  of  this  inequality,  neglecting  its  sign,  is    -rv-—,  multiplied  by 

the  radius  in  seconds    206265'    [4.3141;  and  by  substitutinsr    —  =  f3-r-,and  — =.  ^.^' 

■-  -'  '  •'  ^    M       58,6  '  r"  3454" 

1  m'snai-  [4622a] 

[4321,432.3],  it  becomes  ^^  X    ^^A-  '  ^  206265'.     Putting  this  parallax  equal  to  8',8, 

the  coefficient  becomes  nearly  equal   to    8%8298    [4324]  ;    and  by  using  the  value  of  the 

parallax    8", 56    [5589],  the  coefficient  becomes    8',58    nearly,  as  in  [4622'].     To  reduce 

this  to    7', 5,    the  value  obtained  by  Delambre,  we  must  decrease  the  moon's  mass  in  the 

7  5  1  1 

ratio   of  the  numbers    7', 5    to     8', 58,    so  that  it  will  be  equal  to      — ^x— ^— =7;=-,    [46226] 

8,58         58,6         6/ 

instead  of     -p^rK'f    given  by  the  author  in  [4624]. 

t  (2724)     The  coefficient    31",036  =  10%0556    is  computed,  in   [3376e],  from    the 

formula     — —  .  —  =  10',0556  ;    in  which    X=3    [3376,-3079]  represents  the  assumed    [4625a] 

ratio  of  the  lunar  to  the  solar  force  on  the  tide.  This  value  of  X  is  used,  in  [4319],  in 
computing  the  value  of  m  [4321,4626].  Now,  substituting  X  =  3,  in  [4625a],  we 
obtain, 

~  =  \x  10',0556  =  13%4074  ; 
VOL.  HI.  85 


338  PERTURBATIONS  OF  THE  PLANETS;  [Méc.  Cél. 

[4627]  to  9',55  ;  and  this  result  makes  the  moon's  mass  equal  to  y'y  of  the  earth's 
mass. 

Lastly,  the  third  astronomical  phenomenon  is  the  moon's  parallax.  We 
shall  see,  in  [5605],  that  the  constant  term  contained  in  the  expression  of  this 
parallax,  when  developed  in  a  function  of    the  moon's   true  longitude,    is 

[4628]  3427%93;  supposing  the  moon's  mass  to  be  ^^-g-  of  the  earth's  mass.  Burg 
has  computed   this    constant  term,  by  means    of   a  very  great  number   of 

[4629]  observations  of  the  moon.  He  finds  it  equal  to  3432',04  [5605]  ;  and,  by 
the  formulas  given  in  the  next  book,  this  result  will  be  found  to   correspond 

[4629']     with  a  mass  of  the  moon,   which  is  equal   to  ^l-g-  of  that  of  the  earth.* 


[46256] 


substituting  tliis  value  in  the  first  member  of  the  equation  [4625rt],  we  get  — -—  .  13',4074, 

for  the  mitation,  corresponding  to  any  assumed  value  of  X.     If  we  put  this  equal  to  the  vahie 
Q'jSS,  obtained  by  Maskelyne  [4627],  we  get, 

X  9,5500        ,  9,5500        ^  ,.„      .  ,    r    ,        o  j    i. 

[4  625cl  r~rT^=  .o  ,r.~,.  ;     hence      x=  — -— -r  =  2,4i6,    instead  oi    X=:3,    used  above; 

^  !-{->■        13,4074  cf,o574 

and  as  the  mass  of  the   moon  is    proportional  to    X  [3079] ,  it  mil  be  reduced,  from    r^-^ 
[^•^^^1]'^°    .5-^X3-5=71'     as  in  [4627]. 

*  (2725)     The  constant  term  of  the  parallax  is    —  .(l-f-ee)  [5311]  ;  and  by  substituting 

D  /    M    \i 

[4629a]    the  value  of    —    [5324],  it  becomes  of  the  form  A .  f  j  ;    A  being  a  function  of  the 

known  quantities  a,  e,  he,  which  are  independent  of  M,  m.     Now,  by  using  the  value  of 

—  =^j—     [4628],  we  obtain  the   constant  term   [5330'],  corresponding  to  the  latitude 

whose  sine  is    \/^  ;    also  the  constant  term    3427',93  [5605]  of  the  horizontal  parallax  ; 
hence  we  have, 

[46296]  ^.  ^^^V=3427%93,     and     ./2=3447V32; 

so  that  the  constant  term  of  the  horizontal  parallax  is, 
[46290]  344r,32.(^-^)*. 

Putting  this  equal  to  the  constant  term  of  Burg's  tables    3442',44— 10S40^3432'',04 
[5605],  we  get, 

[4629^]  '^=  gig)  =  1,01341  =  1  +^     nearly,  as  in  [4629']. 


Vl.xvi.§44.]       ON  THE  MASSES  OF  THE  PLANETS  AND  MOON.  339 

Hence  it  appears,  from  all  three  of  these  phenomena,  that  we  must  decrease 

a  little  tlic  mass  of  the  moon,  deduced  from  the  observations  of  the  tides 

at  Brest  ;   therefore,  the  action  of  the  moon  on  the  tides  in  that  port,  is      [4630] 

sensibly  increased  by  local  circumstances.      For  the  numerous   observations, 

both  of  the  heights   and  intervals  of  the  tides,  do  not  permit  us  to  suppose 

this  action  to  be  less  than  triple  the  action  of  the  sun. 

The   most  probable  value  of  the  moon's  mass,  which  appears   to  result 

from  these  various  phenomena,  is  -g-i^y  of  the  earth's  mass.*     By  using  this  [4631] 

value,  we  find  7',572,t     for  the  coefficient  of  the  lunar  equation  of  the  solar  [4632] 

tables,    and    3430%88,t    for  the   constant  term  of  the  expression   of   the  [4033] 

moon's  parallax.     We  also  find    9',648  .  cos.  (longitude  of  the  moon's  node),  [4634] 

for  the  inequality  of  the  nutation,  and    — 18%03.sin.  (long,  moon's  node), ^  [4C35] 


*■  (2726)     Subsequent  observations  of  tbe  tides  at  Brest,  induced  tbe  author  to  reduce 

this  value  of   X    [3079],  from   X  =  3   to   X= 2,35333   [11905];    making  the  mass  of  the     [463ia] 

moon  equal   to  jj.Vjrir  of  that   of  the  earth  [11906];   as   we  have    ah-eady    remarked  in 

[33806',  &ic.].     We  may  observe,  that  the  value  of  X= 3    [4318,4319]  corresponds  with    [46316] 

71»         1  ..ml 

5ri=rr-;  [4321],  and  that  X  is  proportional  to  m  ;  hence  we  get,  m  the  case  of  — =— — 

M      58,6  L  J'  IF  '  o    '  M      68,5     [4631c] 

[4631],  the  value    x=3. ^  =  2,566,     as  in  [4637]. 

t   (2727)     This  equation  of  the  earth's  motion  is  proportional  to     —      [4314]  ;     and  if 

m         1  [4632a] 

we  suppose      —  =  — -    [4321],  it  becomes     8^,58  nearly,  as  in  [4622']  ;  but  if  we  use 

Jrl.  OQjO 

>K        1  58  6  [46326] 

Ti.=^TT     [4631],    this  equation  becomes     8^,58  X  ;;3V  =  7'%34;     which  differs  a  little 
Jn      ob,o  oo,o 

from  [4632]. 

X  (2728)     Substituting    M=68,5.m     [4631c],   in   the  constant  term   of  the    moon's 
parallax  [4629f],  it  becomes    3447%32 .  r^y=  3430^8,    as  in  [4633].     Moreover,  by    [4633a] 
substituting    X= 2,566    [4631c],  in  the  coefficient  of  the  nutation   [4625 J],  it  becomes, 

'^     .13S4074=|^^.13',4074  =  9%648,    as  in  [4634].  [46336] 


1+X         '  3,566" 

§  (2729)      The    coefficients  of  the    inequalities    in    the   nutation    and    precession    are 
represented,  in  [3376e,/,  3378,3380],  by       _f^''  „„      —    ^/^^   ,.cot.2A  ;    which  are  to    [4635a] 


[4638] 


340  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Ce]. 

for  the  inequality  of  the  precession  of  the  equinoxes.  The  ratio  of  the 
[4636]      moon's  action  on  the  tides  to  that  of  the  sun  is  then    2,566  [4631c]  ;  and 

as  the  observations  of  the  tides  in  the  port  of  Brest  make  this  ratio  equal 

to  3  [46316],  it  appears  evident  that  it  is  increased,  by  local  circumstances, 
[4637]      in  the  ratio  of  3  to  2,566.     Future  observations,  made  with  great  exactness, 

will  enable  us  to  determine,   with  precision,   these  points,   in  which  there 

remains,  at  present,  some  slight  degree  of  uncertainty. 

Jupiter's  mass  appears  to  be  well  determined  ;  Saturn's  has  still  some 
degree  of  uncertainty  [4635c],  and  it  is  a  desirable  object  to  correct  it. 
This  may  be  done  by  observing  the  greatest  elongations  of  the  two  outer 
[4638']  satellites,  in  opposite  points  of  their  orbits,  in  order  to  have  regard  to  the 
ellipticity  of  the  orbits.  We  may  also  use,  for  this  purpose,  the  great 
inequality  of  Jupiter  [4417],  when  the  mean  motions  of  Jupiter  and  Saturn 
shall  be  accurately  determined  ;  for  these  mean  motions  have  a  very  sensible 
influence  upon  the  divisor  (5  n"  —  2  n"y,  which  affects  this  inequality.  It 
appears  probable,  that  the  mean  annual  motion  we  have  assigned  to  Jupiter, 
must  be  increased,  one  or  two  centesimal  seconds  ;  and  that  of  Saturn, 
decreased,  by  nearly  the  same  quantity.  The  periodical  inequalities  of  Jupiter 
and  Uranus,  produced  by  the  action  of  Saturn,  afford  also  a  tolerably 
accurate  method  of  determining  the  mass  of  Uranus. 

The  value  we  have  assigned  to   the  mass  of  Uranus,   depends  on  the 
[4641]      greatest    elongation  of   its    satellites,    which    were  observed   by    Herschel. 
These  elongations  should  be  verified  with  great  care. 

With  respect  to  Mercury's  mass,  we  may  use,  in  ascertaining  its  value,  the 

inequalities  it  produces  in  the  motion  of  Venus.      Fortunately,  the  influence 

[4642]      of  Mercury    on   the   planetary  system  is  very    small  ;    so    that   the   error, 

depending  on  any  inaccuracy  in  this   estimate  of  its  mass,  must  be  nearly 

insensible. 


[4639] 


each  other  as   1  to   — 2.cot.2A.     Hence,  if  we  suppose  the  inequality  of  the  nutation  to 
[46356]    ^^    9^,648,    as  in  [4634],   that  of  the  precession  will  be     —  2x9%648.cot.2  A;    and  by 

using     2A  =  52°,1592  =  46''56"'35S8,     it  becomes     — 18',03,    as  in  [4635]. 

Before  concluding  this  note  we  may  observe,  that  the   late   estimates  of  these  masses, 
[4635c]    ^^  different  astronomers,  have  already  been  given  in  [4061  (/—m]. 


VI.  xvii.  <§>  45.]    ASTRONOMICAL  TABLES.    INVARIABLE  PLANE.  341 


[4643] 


CHAPTER  XVII. 

ON  THE  FORMATION  OF  ASTRONOMICAL  TABLES,  AND  ON  THK  INVARIABLE  PLANE  OP  THE 

PLANETARY  SYSTEM. 

45.  We  shall  now  proceed  to  explain  the  method  which  must  be  used  in 
constructing  astronomical  tables.  We  have  given  the  inequalities,  in 
longitude  and  in  latitude,  to  a  quarter  of  a  centesimal  second  ;  but  the  most 
perfect  observations  do  not  attain  to  that  degree  of  accuracy  ;  so  that  we  may 
simplify  the  calculations,  by  neglecting  the  inequalities  which  are  less  than 
a  centesimal  second.  We  must  form,  by  means  of  a  great  number  of 
observations,  selected  and  combined  in  the  most  advantageous  manner,  the 
same  number  of  equations  of  condition,  between  the  corrections  of  the 
elliptical  elements  of  each  planet.  These  elements  being  already  known,  to 
a  considerable  degree  of  accuracy,  their  corrections  must  be  so  small  that  we 
may  neglect  their  squares  and  higher  powers  ;  and  by  this  means  the 
equations  of  condition  become  linear.*  We  must  add  together  all  the 
equations  in  which  the  coefficients  of  the  same  unknown  quantity  are 
considerable  ;  so  that  from  these  sums  we  can  form  the  same  number  of 
fundamental  equations  as  there  are  unknown  quantities  ;  and  then,  by  [4644] 
elimination,  we  may  obtain  each  of  the  unknown  quantities.  We  can  also 
find,  by  the  same  method,  the  corrections  which  may  be  necessary  in  the 
assumed  masses  of  the  planets.  If  the  numerical  values  of  the  planetary 
inequalities  be  accurately  calculated,  which  may  be  ascertained  by  a  careful 
verification  of  the  preceding  results  ;  we  may,  with  each  new  observation, 

*  (2730)     We  have  given  the  form  of  an  equation  of  this  kind,  in  [849(f]  ;    and  have 
shown,  in  [84  9a — r],  how  to  combine  any  number  of  them  together,  by  the  method  of  the     [4644a] 
least  squares  ;  which  process  is  now  generally  used,  in  preference  to  that  in  [4644]. 

VOL.  III.  86 


342  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

form  another  equation  of  condition.  Then  if  we  determine,  every  ten  years, 
the  corrections  resulting  from  the  combination  of  these  equations  with  all  the 
preceding  ones,  we  may,  from  time  to  time,  correct  the  elements  of  the 
orbits  ;  and  by  this  means  obtain  more  accurate  tables  of  the  motions  ; 
[4645]  supposing  that  the  comets  do  not  produce  any  alteration  in  the  elements  ; 
and  there  is  every  reason  to  believe  that  their  action  on  the  planetary  system 
is  insensible. 

46.  We  have  determined,  in  [1162'],  the  invariable  plane,  in  which  the 
sum  of  the  products  of  the  mass  of  each  planet,  by  the  area  its  radius  vector 
describes  about  the  sun,  when  projected  upon  this  plane,  is  a  maximum.  If 
we  put  7  for  the  inclination  of  this  plane  to  the  fixed  ecliptic  of  1750,  and 
n  for  the  longitude  of  its  ascending  node  upon  that  plane,  we  shall  have,  as 
in  [1162'], 

2  .  OT  .  \/a.{\  —  ef)  .  sin.  (p .  siu.  ê 


[4646] 


[4647] 


[4648] 


[4649] 


tang.  7  .  sm.  H: 


tang. 7  .cos.  11: 


2  .  m.^a.(i— ee).COS.  9        ' 
2  .  JW  .  ^«.(1  —  ee)  .  sin.  (p .  COS.  ê 


2.OT.\/«.(1 — ee).COS.(p 

The  integral  sign  of  finite  differences  2  includes  all  the  similar  terms  relative 
to  each  planet.  If  we  use  the  values  of  m,  a,  e,  cp,  and  ê,  given  for  each 
of  these  bodies,  in  [4061 — 4083],  we  shall  find,  by  these  formulas, 

7=      l''35'"3P; 

n=]02''57"'29\ 

Then,  by  substituting  for  e,  tp,  6,  their  values,  relative  to  the  epoch  1950 
[4081—4083,  4242,  &c.],  we  shall  obtain, 

7=      l''35'»3P; 

n=  102'^  57™  15'; 

which  differ  but  very  little  from  the  preceding  values  [4648].  This  serves 
as  a  confirmation  of  the  variations  we  have  previously  computed  in  the 
inclinations  and  in  the  nodes  of  the  planetary  orbits. 


VI.xvm.§47.]  ACTION  OF  THE  FIXED  STARS.  343 


CHAPTER   XVIII. 

ON  THE  ACTION  OF  THE  FIXED  STARS  UPON  THE  PLANETARY  SYSTEM. 

47.  To  complete  the  theory  of  the  perturbations  of  the  planetary  system, 
there  yet  remains  to  he  noticed  those,  which  this  system  suffers,  from  the  [4G49'] 
action  of  the  comets  and  fixed  stars.  Now,  if  we  take  into  consideration, 
that  we  do  not  accurately  know  the  elements  of  the  orbits  of  most  of  the 
comets  ;  and,  that  there  may  be  some,  which  are  always  invisible  to  us,  by 
reason  of  their  great  perihelion  distance,  though  they  may  act  on  the  remote 
planets  ;  it  must  be  evident,  that  it  is  impossible  to  determine  their  action. 
Fortunately,  there  are  many  reasons  for  believing,  that  the  masses  of  the 
comets  are  very  small  ;  consequently,  their  action  must  be  nearly  insensible. 
We  shall,  therefore,  restrict  ourselves,  in  this  article,  to  the  consideration  of 
the  action  of  the  fixed  stars. 

For  this  purpose,  we  shall  resume  the  formulas  [930,  931,  932], 

C  / fl  7?\    ^     "\  exprès- 

a.cos.vfndt.r.ûn.v.  j  2/di2  +  r.r^j  \   )  ^7^1, 


— a. sin.v  .fndt.r. COS. V.  <  2fdR-}-r.(--—\ 


[4650] 


General 


6r:^ 1_£_2_^.  ^x)     [4651] 

t^  •  \/l — ee 

2r.d.ôr+dr.Sr     3a                  jr>  ,  2a    „     ,^        /^7?\ 
5 — 7 .ffndt.dR-] .fndt.r. (  —  ) 

6V^ '^^^ ^—7— '— ^^;  (Y)      [4652] 

V/l— ee  '  ^    ^ 

^     ,,         .         /dR\  .  .     .  /dR\ 

a. cos.  V.J  ndt.r.Hva.v.y  —  1 — a. sm.v. J  ndt.  r  .cos.r.(  —  j 

S  s  = /./1 ^-^-  (^      [4653] 

f^.y/l  —  ee 


344  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 


[4654] 


We  shall  put  m'  for  the  mass  of  the  star  ;  x',  y',  z',  its  three  rectangular 
co-ordinates,  referred  to  the  sun's  centre  of  gravity  ;  r',  its  distance  from 
that  centre  ;  a:,  y,  z,  the  three  co-ordinates  of  the  planet  m  ;  and  r,  its 
distance  from  the  sun.     We  shall  have,  as  in  [3736], 

[4655]  R  =  >»'-(^^'+yy'+~^')   _  m! 

Developing  the  second  member  of  this  equation,  according  to  the  descending 
powers  of  r',  we  shall  have,* 

[4656]  ^=—7  +  -jTT—i^'-         ^^      ,-5  ' &C. 


[4656'] 


We  shall  take,  for  the  fixed  plane,  that  of  the  primitive  orbit  of  the  planet  ; 
and  we  shall  have,  by  neglecting  the  square  of  z,f 

[4657]  X  =  r  .  cos.  V  ;  y  =  r  .  sin.  v  ;  z  =  r  s. 

[46581      Putting    I    for  the  latitude  of  the  star  m',    and     U    for  its  longitude,  we 
obtain,  Î 

[4659]  a;' =r'.  cos.  Z.  C0S.C7:  ?/'=?•'.  cos. /.  sin. C/;  2' =  r*.  sin. /. 


*  (2731)     Putting,  for  brevity,    xx' -\-yy'-\-zz'=zrr'.f;    and,  as  in  [914'], 
[4655a]  a;2-|-/-f22  =  7-2,  x'^+y'^ -}-z'^=r'% 

we  find,  that  the  last  term  of  [4655]  becomes,  by  successive  reductions,  as  in  [4655c]  ; 

[46555]     _„/.|(.,'_:,)2+(y'_y)^+(z'-_^)«f*=-_m^{r'2-2r'r/-^r«r*=-p.{l-2('^^')J"* 

[4655c]  __-'_-7?:;^^^^U?.™'.f^i^*'^^f  _  &c. 

r'       r    \      r'^     J      2    r'    \      r'2      / 

Substituting  this  in  [4655],  we  find  that  the  first  term  of  [4655]  is  destroyed  by  the  second 
term  of  [4655c],  and  the  whole  expression  of  R  becomes,  by  a  slight  reduction,  as 
in  [4656]. 

t  (2732)     The  values  of  x,   y  [4657],  correspond  with  those  found  in  [926'— 927]. 
[4657a]    The  value  oî  z^rs  [4657]  is  the  same  as  that  in   [931"],  changing  as  into  s,  to  conform 
to  the  present  notation. 

\  (2733)     The  radius  vector  of  the  body    m'    is    /,    and  its  latitude  above  the  fixed 

[4659a]     plane  /.     Hence  it  is  evident,  from  the  principles  of  the  orthographic  projection,  that  the 

projection  of  r',  upon  the  fixed  plane,  is  /.cos./;  and  the  perpendicular  z',  let  fall  from  m'. 


Vl.x™i447.]  ACTION  OF  THE  FIXED  STARS.  346 

Hence  we  deduce,  by  neglecting  the  descending  powers  of  r',  below  Z"^,*        [4059] 

/?=  — ^'  +  '1^'  •  )<2— 3.cos.=Z— 3.cos.=/.cos.(2i;— 2C/)— 65.sin.2/.cos.(v-t7)|.      [4(iG0] 

Now,  ?"',  /,  and   U,  vary  nearly  by  insensible  degrees  ;    hence,  if  we  put  R^     [4661] 
for  the  part  of  R,  divided  by  r'^,  and  neglect  the  square  of  the  excentricity 
of  the  orbit  of  m:    also,  the  term  dependine;  on  5,  which  is  of  the  order  of 

lb'  [4661'] 

the  disturbing  forces,  that   m   suffers  by  the  action  of  the  planets  ;  we  shall 
have,t 

fAR==R-  ^-^' .  (2  -  3  .  cos.^Z)  ;  [4662] 

r.(g)  =  2i?,  -  [4662-] 


upon  the  fixed  plane,  is  equal  to  /.sin./,  as  in  [4659].  Now,  this  projected  radius  r'.cos.l, 
makes  the  angle  U  with  the  axis  of  x  [4658,  Sic],  and  90'' — U  with  the  axis  of  «/. 
Hence  we  easily  obtain  expressions  of  x',  y',  similar  to  those  of  x,  y  [4657],  and  which 
may  be  deduced  from  them,  by  changing    r    into    r'.cos.l,    and    v    into  U,  as  in  [4659]. 


[46596] 
[4659c] 


*  (2734)  Substituting  the  values  of  J",  y,  &c.  [4657,4659],  in  the  first  member  of 
[4660a],  reducing,  developing  and  neglecting  terms  of  the  order  s^,  we  get,  by  using 
[24, 6, 31]  Int.  the  following  expressions, 

\xx'-\-yy'-\-zz'l^^^r"r'^.\cos.I.(cos.v.cos.U-\-s\n.v.sm.V)-{-s.sin.I\^  [4660a] 

=r^/^.  ^cos.Z.cos.(w — [7)-)-s.sin. /}^ 
^7-^r'^.{cos.^Lcos.^(«  —  [7)4- 2s. sin.  Z.cos.Z.cos.(« — U)l 
=r2r'2.^cos.2Z.[|+icos.(2i;  —  2Z7)]+«.sin.2/. cos.  («—[/)}.  [4660i] 

Now,  the  first  and  second  terms  of  [4656],  are  the  same  as  the  first  and  second  terms  of 
[4660]  respectively  ;  so  that  if  we  neglect  terms  of  the  order  mentioned  in  [4659'J,  we 
shall  find,  that  the  remaining  part  of  [4656]  becomes, 

—  -^  -{xx'+y  y'+z  2'  p.  [4660c] 

Substituting  in  this  the  expression   [4660e],  it  produces  the  three  last  tenns  of  il  [4660]. 

t  (2735)     If  we  use  the  symbol    R,,    we  shall  have,  from  [4660,4661], 

iî^=^-Ç.j2  — 3COS.2/— 3cos.2Z.cos.(2y  — 2f7)  — 65.sin.2/.cos.(j;— Z7)i  ;  [4662a] 

^=  —  ~'+^'  [46626] 

VOL.  III.  87 


346 


PERTURBATIONS  OF  THE  PLANETS; 


[Méc.  Cél. 


[4662"] 


Then,  if  we  put  n  =  1,  which  is  nearly  equivalent  to  the  supposition,  that 
the  sun's  mass  is  equal  to  unity  [3709],  we  shall  obtain  from  the  formula 
[4651],* 


[4669e] 

[4662rf] 

[4662rf'] 
[4662e] 

[4662/] 

[4662e-] 
[4662^1] 

[4662i] 

[4662fe] 
[4662  i] 

[4662m] 
[4662n] 

[4662o] 
[4662o'] 

[4662p] 
[4662fl] 


The  characteristic  d  affects  the  elements  of  the  orbit  of  the  body  m,  namely,  r,  »,  s,  inc.  ; 
but  does  not  affect  those  of  the  body  ?»',  as  r ,  I,  U,hc.;  hence  the  differential  of  [46626] 
becomes,  àR=àR^.  Integrating  this,  and  adding,  as  in  [1012'],  the  constant  quantity 
m'g,  to  complete  the  integral,  we  get /dfi=/d/î,+  m'^.  Now,  as  r',  I,  U,  are  nearly 
constant,  we  may  neglect  their  variations,  and  then  the  quantity  di?,  will  be  the  complete 
differential  of  /?,  ;  so  that  we  may  write  R,  for  fdR/,  hence  the  expression  [4662f/] 
becomes  fdR^R^-j-m'g.  If  we  neglect  terms  of  the  order  e^,  in  the  expression  of 
r  [1256],  it  becomes  as  in  [4664];  and  if  we  substitute  this  in  the  expression  of  r^.dv 
[1256],  we  easily  obtain  the  expression  of  ndt  [4664].  By  inadvertence,  the  author  has 
given  a  wrong  sign  to  the  term  depending  on  e,  in  the  value  of  r  [4664] ,  wliich  in  the 
original  work  is  r  =  a.{l-j-e.cos.(D  —  ro)|.  This  affects  the  numerical  coefficients  of  the 
formulas  [4666,4666',&tc.],  but  does  not  alter  the  general  results  [4669',4673,&.c.].  Putting, 
for  brevity,  h  equal  to  the  coefficient  of  r"^,  in  the  expression  of  R^  [4662a],  we  have. 


h=  ^.{2— 3. cos.^l— 3. cos.-l.cos.{2v  —  2U)  — 6s. sm.2l. COS.  {v—U)l 


R.=  h.i 


whence 


dR\ 


:2A  r  = . 

r 


we  obtain  the 


Substituting  this  in  the  partial  differential  of   R    [4662è],  relatively  to 
following  expression, 

\d^)      \d^)  ~  T  ' 

multiplying  this  by  r,  we  get  [4662'].  If  we  determine  the  constant  quantity  g,  as  in 
[1016",&.c.],by  making  the  coefficient  of  t  vanish  from  the  expression  of  ôv,  we  shall  find, 
by  putting  fj.=l,  and  neglecting  e^,  that  the  terms  of  5v  [4652],  necessary  to  be  noticed 
in  finding  the  constant  quantity,  are, 

a.f{3fàR+2r.(~y.ndt. 

Substituting  the  values  [4662e,  4662'],  it  becomes,  a  ./{I R,-{-3m'g).ndt  ;  and  if  we 
retain  only  the  constant  part  of  R,,  the  preceding  expression  will  vanish,  and  we  shall  have 
the  constant  part  ot  Sv  equal  to  nothing,  by  putting  7  Ri-\-3m'g  =  0;  or  m'g=^ — i-H^r 
Now,  the  constant  part  of  R^  is  evidently  obtained,  by  putting  r^=a,  and  retaining  only 
the  two  first  terms  of    [4662a].     Hence  we  get, 

,  7 m'.  cfi    ,-       n  o  7\ 

^*^=-"Ï27T-(^~^-'=°'-')' 
and  fàR    [4662c]   becomes  as  in  [4662].     In  the  original  work  the  numerical  coefficient 
is    — \,    instead  of   — ^^. 


*  (2736)     From  [4662e,  4662'],  we  get. 


VI.xnii.§47.]                     ACTION  OF  THE  FIXED  STARS.  347 

6  r  =  4  a  .  COS.  v  .fn  dt.rR,.  sin.  v  —  4.a.  sin.i;  ./n  dt.rR,.  cos.  î;.  [4663] 
Substituting  the  following  expressions  [1256,  4662/,  &c.], 

r  =  a.\\-e.cos.(v-^)\;             n  dt  =  dv  .{I— 2e  .cos.  (v —  ^)\;  [4664] 

and  neglecting  under  the  sign  /,  the  periodical  terms,  affected  with  the  angle  [4665] 
V,  we  shall  have,* 

ndt.r.R,cos.v=-^^\{(l-hcos.H).e.cos.^-hcos.H.e.cos.(^-2U)];  [4666'] 


2/d  /Î  +  r .  (^)  =  4  i?,+  2  m'g.  [4663a] 

Substituting  this  in  [4651],  also    ii=l,    and  neglecting  c^,  we  get, 

—  =4. COS. ■y./'ri(/«.r iî,. sin. i;  —  4.sin.i).  AitZ^.r-R^.cos.v 

a  "^  '  ^  '  [4663a  ] 

-(-2m'^.cos.t)./nf/<.r.sin.î) — 2mg.sm.v.f7idt.r.cos.v. 

This  differs  from  [4663],  in  the  terms  multiplied  by    g.     The  two  expressions  would  agree, 

if  we  were  to  take  the  arbitrary  constant  quantity    g    [4662d]  equal  to  nothing  ;  but  this  J 

would  be  inconsistent  with  [4662?t,  4668]. 

*  (2737)      From   [4662/],  we  obtain      ndt.rR,^h.ndt.r^.       Now  we  have,  by 
neglecting  e^      r^  =  a^.\l  —  .3  e.cos.fw— «)|   [4664];     multiplying  this  by    ndi    [4664],     [4666a] 
we  get, 
ndf.r^=:a^.dv.\l — 5e.cos.(«  —  ■a)\;  hence,  ndt  .rR  =  h.a^.dv.\\  —  5e.cos.(«j — ro)}.     [46666] 

Multiplying  this  successively,  by  s'm.v,  and  cos.d,  we  get,  by  reduction, 

ndt  .r  R^. sm.v^=  h  .a^.dv  .\s\n.v — f  e.sin.-a — f  e.sin.  (2«  —  ra)|;  [4666c] 

ndt .  r  R^ .  cos.t)  =h.a^.dv  .\  cos.t)  —  |  e .  cos. is  —  f  e .  cos.  (2  v — o)  | .  [4666rf] 

The  second  of  these  expressions  may  be  derived  from  the  first,  by  augmenting  each  of  the 

angles  v,  zs,   U,  by  90';    as   appears,  by  making  this  change  in  the  second  members  ;   no    [4666e] 

alteration  being  made  in  /,  /,  &c.;  so  that  h  [4662^-]  may  remain  the  same.  If  we  suppose 

the  plane  of    x  y,     to  be  the  primitive  orbit  of  m,    the  latitude    «    will  be  of  the  order  of 

the  disturbing  forces  of  the  planets,  which  is  neglected  in  [4661']  ;  and  then  A  [4662A:]  is 

composed  of  the  two  terms, 

^.(2  — 3.COS.2/),  _|^3.3.cos.2Z.cos.(2t;— St;-).  [4666^] 

Tliese  are  to  be  substituted  in  [4666c],  and  those  terms  retained,  which  do  not  contain  the 


348 


PERTURBATIONS  OF  THE  PLANETS  ; 


[Méc.  Cél. 


[4666"]    which  gives,  by  considering    ïs,    Z,    r',    U,    as  very  nearly  constant,^ 
5r       3m'.a^.v 


[4667]        -  = 


.{(1 — I .  COS.-/).  e  .  sin.(z) — w)  — a.  cos.'Z.  e  .  siu.(t)4-w — 2C7)|. 


[4666i] 
[4666fe] 

[4667a] 

[46676] 
[4667c] 

[4667d] 

[4667e] 
[4667/] 

[4667gr] 
[4667A] 


angle    v,   or  its  multiples   [4665]  ;    consequently,  the  first  of  these  terms  of  h   must  be 
combined  with  the  second  of  [4666c]  ;  and  the  second  of  these  terms  of  h,    with  the  third 
of  [4666c]  ;  hence  we  shall  have, 
m'.  a?,  dv 


[4666A]         ndt.  rR, .  sin.  v  =  • 


4,. '3 


.f— (2  — 3.cos-2Z).Ae.sin.«— V-e.cos.2/.sin.(«— 2t7)|; 


which  is  easily  reduced  to  the  form  [4666].  In  like  manner  we  may  compute  [4666']  ;  or, 
we  may  obtain  it  much  more  easily,  by  derivation  from  [4666],  by  increasing  the  angles 
V,  «,  V,  by  90'',  as  in  [4666e].  These  results  are  free  from  the  error  in  the  value  of  r 
[4662^]  ;  and  if  we  compare  them  with  those  given  by  the  author,  in  the  original  work,  we 
find,  that  we  must  multiply  his  expressions  by  — 5,  to  obtain  those  in  [4666,4666']  ;  or, 
in  other  words,  we  must  change  e  into    — 5e,  in  his  formulas. 


*  (2738)     Putting,  for  brevity, 

.       5m'.  a^    ,,        „  „,, 


I5m.a?  „ 

B^  —^—-  .COS.  I .  e  ; 
16r'3 


we  find,  that  the  integrals  of  [4666, 4666']  become,  very  nearly, 

f7idt.7-R^.sïn.v= — ^î'. sin. 13 — 5u.sin.(^3  —  2U)  ; 
fndt.r  R^.cos.v= — Av  .cos.zi-\-Bv.cos.(-Gs —  2U). 

Multiplying  the  first  of  these  expressions  by  4.cos.i',  the  second  by  — 4.sin.K,  and  taking 

the  sum  of  the  products  ;    putting 

— sin.  ra.cos.v-j-cos.a.sin.i)  =  sin.  [v  —  to)  ; 

—  sin.(« — 2U).cos.v  —  cos.  (to  —  2t/).sin.i)  =  — sin.(w  +  TO  —  '2U)  ; 

we  get,  for  the  terms  in  the  first  line  of  [4663a'],  the  following  expression, 

4 .  cos.  v.fndt  .rR^.  sin.  i'  —  4 .  sin.  «  .fn  di  .rR^.  cos.  v 

^4:.A.v.sm.(v — to)  —  4.B  .v.s\n.{v-\--a  —  2U). 

Again,  if  we  multiply  together  the  expressions  of  r  and    ndt  [4664],  neglecting  e^,  we 

obtain, 

ndt  ,r  =^  adv  .\l  — 3e  .cos.  [v  —  ^)}. 

Multiplying  this,  successively,  by    sin.r,    cos.  d;    reducing  and  retaining  only  the  terms, 
which  are  independent  of  the  angle    i',    we  get. 


ndt.r.s'm.v  =  — adv. ^e.sm. -a  ; 
fii dt  .r.s'm.v  =  —  a w . |  e . sin. to  ; 


ndt  .r.cos.v 


-adv  .^e. COS. zi. 


fndt.r.  COS.  d  =  —  av.^c.  cos.  i 


Multiplying  these  integrals,  respectively,  by     2?n'^.cos.D,      — 2m'g.s'm.v  ;     taking  the 
sum  of  the  products,  and  reducing,  by  means  of  [4667  J];   then  substituting  the  value  of 


VI.  xviii.  §  47.]  ACTION  OF  THE  FIXED  STARS.  349 


Now  we  have,* 

Sr 
a 


—  ôe  .  COS.  (v  —  ^)  —  e  (5 3  .  sin.  (v  —  ^).  [4668] 


Secular 
variations 


Comparing  together  the  two  expressions  [4667,  4668],  we  obtain,t  iriïè 

excentrici- 
ly  ami 
1  'Î  m'    /7^ï'  perihelion. 

5 e  =        '-""■"     .  cos.^Z .  e  .  sin.  (2  ^  —  2U)  ;  [4669] 

S^=  _  iî^!i'.p_3  .  cOS.^Z  —  I  .  COS.^Z.  COS.  (2^  —  2U)].  [4669'] 

Thus  the  action  of  the  star  m'  produces  secular  variations  in  the  excentricity  and 

in  the  longitude  of  the  perihelion  of  the  orbit  of  the  planet  m;  but  these  variations 

are   incomparably  smaller  than  those   arising  from  the  action  of  the  other     [4669"] 

planets.     For,  if  we  suppose    m    to  be  the  earth,  r'    cannot,  by  observation. 


m'g  [466-2y],  we  finally  get,  for  the  second  line  of  [4663a'], 
2  m'g .  cos .  V  .fn  dt  .r.s'm.v  —  2  m'g .  sin .  î)  .fn  dt.r.  cos.  v 

=  2m'g.^.ave  .  j  —  sin.w.cos.  v  +  cos.ra.sin.i)  |  [4667i] 

=  m'g.^ave.sm.{v  —  «)  = 9~^3~'^^ — f  .cos.'^/j.e.sin.  (w  —  «).         [4667fc] 

Adding  together  the  expressions  [4667e,^-];  re-substituting  the  values  of  A,    B    [4667cr], 
we  get  the  complete  value  of     —     [4663rt'],  as  in  [4667].     In  the  original  work, the  author      [466/^] 

.3  m'.  a^v 


makes  the  factor,  which  is  without  the  braces,  equal  to V^ — )     instead  of         „  ,,    » 

and  the  numerical  coefficient  of  the  second  term  within  the  braces  is  erroneously  printed 
—  f  instead  of  — J.  These  mistakes  are  the  consequences  of  using  erroneous  values  of 
g  and  ;■   [4662o',  p]. 


[4667m] 


*  (2739)     In  finding  the  variation  of  r   [4664],  we  must  neglect  that  of  v,  arising  from 
the  constant   quantity   g'  [4662/i],  and  the   expression  becomes  as  in   [4668]  ;  which  is     MQgg;,-] 
similar  to  [3876].     The  signs  of  the  terms  in  the  second  member  of  [4668],  in  the  original 
work,  are  incorrect,  by  reason  of  the  mistake  mentioned  in  [4662^-]. 


[4669o] 


t  (2740)     From  [21]  Int.  we  have, 

sin.{f  +  3— 2f7]  =sin.[(y  — îs)  +  (2w  — 2t7)} 

=  sin.  (v — ra)  .COS.  (2zs  —  2U)-\-cos. {v  —  a)  .sin.  (2zi —  2U). 

Substituting  this  in  the  last  term  of  [4667],  and  then  comparing  separately,  the  coefficients 
of  sin.  (i-  —  3j)  and  cos.(i'  —  w),    in  the  two  expressions  [4667,  4668]  ;  we  get,  by  a  slight     [46696] 
reduction,  the  values  of  6  e,    ôtz  [4669,4669'].     These  expressions  agree  with  those  given 
VOL.  III.  88 


350  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

t       3 

[4670]     be  supposed  less  than  lOOOOOa,  and  then  the  term  '^^-^,  does  not  exceed,* 
[4671]  m'^.0%000000001  ; 

t  denoting  the  number  of  Julian  years.  This  is  incomparably  less  than  the 
[4671']  secular  variation  of  the  excentricity  of  the  earth's  orbit,  resulting  from  the 
The  ao-      action  of  the  planets,  which,  by  [4244],  is  equal  to. 

Stars  has 

[4672]  —  ^.0',093819, 

no  sensi- 
ble effect 


ontheex-    uiiloss  we  suDDOsej  that  m'  has  a  value  which  is  wholly  improbable.     Hence 

centrici-  J  L 

ties  and 
perihelia 
of  the 


we  may  conclude,  tJiat  the  action  of  the  stars  has  no  sensible  influence  on  the 
p'ian'e"ts.  secular  variations  of  the  excentricities  and  perihelia  of  the  planetary  orbits. 
[4673]     In  like  manner,  it  is  evident,  from  the  development  of  the  formula  [4653], 

that  their   action  has  not  any  sensible   influence   on   the   position  of  these 

orbits.f 


by  Mr.  Plana,  in  the  Memoirs  of  the  Astronomical  Society  of  London,  vol.ii.  p.  354  ; 
which  he  deduced  from  the  formulas  [1253a].  Hence  we  see,  that  the  method  here 
f4669cl  proposed  by  La  Place,  to  find  5e,  Sw,  when  it  is  correctly  followed,  leads  to  an  accurate 
result  ;  and  is  not  liable  to  the  objection  made  by  Mr.  Plana,  in  the  same  page  of  that 
volume,  namely;  that  it  is  nowise  fit  for  the  intended  purpose,  without  taking  into  view  other 
circumstances,  which  render  the  calculation  more  complicated.      We  may  remark,  that  in 

[4669(/]    the  original  work,  the  factor  -y-  [4669],  is  printed  J  ;    and,  in  [4669'],  the  factors —, 


[4669e]     — f.cos.%    are  changed  into ,     — J.  cos.®/,     respectively 


*■  (2741)     The  value  of   ?-=100000a    [4670],   corresponds  to  an  annual  parallax  of 
[4671a]    about    2';    and  we  have  nearly    «=1295977'.^    [4077];    substituting    these   in     — j^- 
[4670],  it  becomes  as  in  [4671]  ;  or  simply,  by  supposing    7ft'=  the  sun's  mass  =  1, 

^0',000000001. 
The  secular  variation  of   c"  [4330a],  is  nearly  represented  by, 
[46716]  -^.<=  — i.(0%187638).^=— 0',093819.!:     [4244,4672]; 

which  is  much  greater  than  the  expression  [4671]. 

t  (2742)     If  we  substitute     rs  =  z    [4657],  in     R^,    R    [4662i,  «],   and  retain  only 
*■        "•'    the  terms  of   R,    containing    z,    we  find, 

[46736]       R= j-j^  .sm.2l.cos.{v  —  U),         and  f— j  =  —  — ^  .sm.2/.cos.(t)  —  U) . 


VI.xvrii.§47.]  ACTION  OF  THE  FIXED  STARS.  351 

PFe  shall  noio  examine  into  the  influence  of  the  attraction  of  the  stars  on  the 
mean  motion  of  the  planets.     For  this  purpose,  we  shall  observe,  that  the 
formula    [4652]  gives,   in    d.6v,    the  term*    dAv  =  ^andt  .R/,      from      [4674] 
which  we  deduce  the  following  expression,! 

d.iv='^  .ndt. {2  —  5.  co^.H].  [4675] 

We  shall  put 

r'=r;.  (1-aO;  /=Z^. (1-/30;  [467G] 

r'  and  /    being  the  values  of  r'  and  /,  in  1750,  or  when  /  =  0;    we  shall     [407G'] 
have,  in  &v,  the  variation, f 

6  V  =  ^-^  .  ri  —  # .  cos.%)  .  a .  ,1  f—  ^-^.  sin.  2l.^.nt\  [4677] 


Substituting   this  in    S  s    [4653],  we  find  that  the  terms  are  multiphed  by  the  very  small 
factor  of  the  order  [4670,4671],  which  renders  them  insensible  [4671']. 

*  (2743)     This  expression  arises  from  the  last  term  of  5v  [4652],  which,  by  neglecting 
quantities  of  the  order    e^,    and  putting     jj-^I    [3709],  becomes, 

2afndt.r.  (^\  =  2afndt.2R,     [4662'] .  [4674a] 

Its  differential  gives,  in     d.5v,    the  terra    Aandt.R^,     as  in  [4674].      This   would   be 
increased  to    landt.R^,    by  noticing  the  term  depending  on   fàR    [46-52],  as  we  have      [46746] 
seen  in    [4662o'].     This  increases   the  terms    [4675, 4677]  in   the  ratio  of  7  to  4. 

m'  r- 

t  (2744)     The  two  first  and  chief  terms  of   R,    [4662a],  are     -^  •  (2—  Z.cos.^l)  . 

Substituting  the  value  of   r    [4664],  we  obtain   the   part      rrj  •  (2 — 3. cos.-/),     which     [4675o] 
does  not  contain    v  ;    hence,  the  term  of   d.Sv    [4674],  becomes  as  in  [4675]. 

Î  (2745)     The  value  of   /    [4676]  gives     cos.?  =cos.(/,— p^/,)  =  cos./,-f-p^sin./,,     [467Ga] 
by  using  [61]  Int.    Squaring  this,  neglecting  i^,  and  putting  2 .  sin.  /,.  cos.  /,=  sin.  2/,  [31]  Int., 
we  get  cos.^I  =  cos.^/^ -\-^t- sin. 2 Z,  ;    whence, 

2  — 3.cos.2/  =  2.(l— f.cos.2/,)— 3(3/.sin.2/,.  [46765] 

If  we  now  substitute  the  value  of  r'  [4676],  in  the  first  member  of  the  following  expression, 
and  then  develop  it  according  to  the  powers  of  a,  neglecting  a*,  we  get, 

-^.ndt  =  —j^  .7idt.{l-lr3o-t).  [4676c] 


352  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél- 

We  cannot  ascertain,  by  observation,  the  value  of  aï,  but  may  determine  that 
of   f3t.      Now,  if  we  suppose,  relatively  to  the  earth,    f3=l"^  U%324,    and 

[4678]      ,,'  ^^  100000  a  ;     the  quantity     -^  .  ^nf   becomes,  very  nearly,* 

^/ 

[4679']     which  is  insensible,  from  the  time  of  the  most  early  observations  on  record. 

The  expression  of   d.&v,    contains  also,  by  what  precedes,  the  terms, f 
[4680]      dM^=—i.m\a\ndLfAy-^~.cos.{v—U)\—&tri;M\ndt.Sp^l.co^^^^^ 

Multiplying  together  the  expressions  [4676i,  c],  we  get  the  value  of  d .&v  [4675],  nearly, 

[4676d]     tZ.5u=z — JL  ,ndt.{\  —  %.cos.H\A —- .(1  — J.cos.^/J.an^t/i 7T-.sm.2Lsnic/;. 

We  may  neglect  the  first  term  of  this  formula,  because  we  have  taken  the  constant  quantity 
[4676c]     ^  so  as  to  make  the  coefficient  of  t  vaftish  from  the  expression  of  5«  [4662«].    Integrating 
the  other  two  terms  of  [4676c/],  we  get  the  value  of  h%)  [4677]. 

*  (2746)     The  assumed  values  of  (3,     r/,   are  taken  within  reasonable  limits  ;  since  the 

value  of  p  corresponds  to  an  annual  variation  in  tlie  latitude  of  the  star,  of  about  a  third  of  a 
[4679a]     sexagesimal  second  ;    and  the  value  of  r/  to  an  annual  parallax  of  nearly  two  sexagesimal 

seconds.     To  reduce  the  expression  [4678]  to  numbers,  we  have,   in  the   case  of    i=\, 

nt  =  circumference  of  the  circle  =  C,2S.31  ;    hence,  generally, 
[46796]  „  <  =  6,2831  .t;         also,         p  t  =  0',324  .  t. 

The  product  of  these  two  expressions  is, 
[4679c]  fi7i(^  =  2',0357 .  t^ 

Substituting  this,  and    rf=l0^.a,    in  the  first  member  of  [4679],  it  becomes   as   in  the 

[4679d]    second  member  of  that   equation.     This   is  wholly  insensible   in  observations  made  3000 

years  ago  ;  since,  by  putting  t  =  — 3000,  and  7«'=:1,  it  becomes  less  than  O',00000002. 

t  (2747)     If  we  now  notice  only  the  terms  of  R,    R,  [4662rt,  b'\,  depending  on    s,  we 
obtain, 

[4680a]    Rz=  —  f  ."^  .«.sin.2/.cos.(i' — U)  ;     whence,  r.f—j^ — 3.^^.s.sin.2/.cos.(t) — ['). 

If  we  substitute  the  value  of  r  [4664],  and  neglect  terms  of  the  order  es,  we  get, 
[46806]    R=  —  f.m'.a^.  } ~^ — .cos.(«  — Z7)|  ;  r.  f  — 1  =  — 3. -^  .s.sm.2/.cos.(«— t'). 

Now,  if  we  put    (J.=  l,    and  neglect  e^  ;    noticing  only  the  terms  of  [4652],  where  R 


VI.  xviii.  §47.]  ACTION  OF  THE  FIXED  STARS.  363 

Now  we  have,* 

s  =  t .—  .  sin.  I'  —  t--r--  cos.i)  ;  t^^^^] 

(It  (It 

which  gives,  by  neglecting  the  quantities  multiplied  by  the  sine  or  cosine  of 
the  angle  v,f 


s.sin.2/  ,  y.^        ^    sin. 2/     (.  dq       .     jj       dp    ^^^  tj\  . 


[4682] 


[4683] 


consequently, t 

,.  ,     s. sin. 21  .  rr\         ,    sin.2Z    ^dq       .      ^r       '^  V  tt} 

i  d  . -^3- •  COS.  (t' -C/)  =  ^ . -^^.  I  ^  .  sin.t/-^^ .  cos.f/ ^  . 

Hence  we  obtain,  in    d.6v,     the  term,^ 

^.,^,=_l^î^^„^^^.sin.2^5^.sin.C7-^.cos.f7^  [4684] 

4        r^  i  dt  dt  3 


[4G80c] 


explicitly  occurs,  we  get,  for  its  differential, 

dJjv  =  3a.7idt.fdR~\-2a.7idt.r.  (-77  )• 

Substituting,  in  the  first  term  of  this  expression,  the  value  of  R  [46S0J],  we  get  the  first 

term  of  [4680]  ;    and  we  obtain  the  last  terni  of  [4680],  by  the  substitution  of  the  second    L  •'      1 

expression  [4680&]  in  the  last  term  of  [4680c]. 

*  (2748)     This  expression  is  similar  to  that  in  [3802, Sic.].     We  may  remark,  that  the 
author,  in  this  article,  has  interchanged  the  usual  signification  of  the  symbols   p,    q  [3802].    [4681n] 
We  have  rectified  tliis,  by  changing  jj  into  q,  and  q  into  p,  in  all  the  formulas  [4681 — 4685] 
of  the  originLil  work. 

sin.2i 
t  (2749)     If  we  multiply  the  expression  [4681]  by     — ^.cos.(i'  —  U),     and  reduce 

the  products  by  [19,  20]  Int.,  we   shall  obtain  the  equation  [4682],  by  retaining  only  the    [4682a] 
terms   which  are  independent  of  1;;  or  in  other  words,  by  retaining  only  the  terms    |sin.f/, 
^cos.f-^,   of  the  expressions  sin.  v. cos. (»  —  U),  and  cos.  v . cos.  (u — U),  respectively. 

X  (2750)     If  we  neglect  the  variations  of  r',  /,    U,  in  the  second  member  of  [4682],  the 
sign  d  may  be  considered  as  the  complete   differential,  and  then  the  signs  /d,    mutually    [46e3aJ 
counteract  each  other,  and   they  may  be  prefixed   to  the  first   member  of  [4682],  without 
altering  its  second  member;  hence  we  get  [4683]  from  [4682]. 

§(2751)     Multiplying  [4683]  by    —  ^  .m'.d^n  dt,  nnd  [4682]  by    —Q.m'.({\ndt, 
we  find,  that  the  sum  of  the  products,  or  the  second  member  of  [4680],  is  as  in  [4684].     l'1684«| 
Integrating  this,  we  get,  [4685]. 

VOL.  in.  89 


354  PERTURBATIONS  OF  THE  PLANETS  ;  [Méc.  Cél. 

consequentlj,  we  have,  in    6  v,    the  secular  inequality, 

[4685]  5x,  = .  _^,nt\  sm.  2Z.  \  -/-.sm.U  —  —  -  cos.t/  S  . 

8         r*  I  (It  dt  5 

We  have  given  the  values  of  -— ,  -j-,  [4332],  relatively  to  the  earth. 
If  we  substitute  them  in  the  preceding  term  of  &v  [4685],  we  shall  find 
that  it  is  insensible,*  even  in  the  most  ancient  observations. 


*  (2752)     From   [4332]  it  appears,  that     — -,      — -,    are  each  less  than  F,  and  sin. 2/, 

sin.ZJ,  cos.f^,  do  not  exceed  unity  :  tlierefore,  sin.2/.  <  •—- .sin.t/ — —-  .cos.U  )■  ,  maybe 
[4685a]  ■'  '  i  dt  dt  <,  ■' 

considered  as   less  than  V  ;  and  then,  the  expression  [4635],  neglecting  its  sign,  becomes 

21     m'.a? 
less  than     —  .  —7 —  .nt^.V  ;     which  is  found  to  be  insensible,  in  [4679']. 
8        r'3 

Other  terms  of  the  like  nature  with  those  which  have  been  particularly  examined,  in  this 

[46856]     chapter,  may  be  deduced  fiom  the  formulas  [4651 — 4653]  ;  but  it  is  evident,  from  what  we 

have  seen,  that  they  must  be  excessively  small  ;  so  that  it  is  hardly  worth  the  labor  of  a 

r../-o^  1    more  thoroudi  examination.     The  author  himself,  seems  to  have  considered  the  subject  as 
[4685c]  °  ...  ... 

not  deserving  much  attention,  and  has  been  quite  negligent  in  the  numerical  details  of  this 

article  ;  so  that  it  has  been  found  necessary  to  correct  the  text  in  several  places,  as  we  have 
[4685(/]    already  remarked.     In  writing  the  notes  on  this  volume,  soon  after  its  first  publication  by  the 

author,  I  pointed  out  the  mistakes  in  this  chapter.       It  has  since  been  done  by  Mr.  Plana,  in 

vol.  ii.  p.  351  of  the  Memoirs  of  the  Astronomical  Society  of  London,  for  1826;  and 
[4685e]     subsequently  by  La  Place,  in  the  Connaissance  des  Terns,  for  the  year  1829,  page  250.  The 

method  used  by  Mr.  Plana  is  more  direct  and  simple  than  that  of  the  author.  It  consists  in 
[4685/]    substituting  the  value  of  R  [4660],  in  the  formulas  [5787—5791],  and  making  the  necessary 

reductions  ;  but,  as  the  process  is  simple,  it  is  unnecessary  to  enter  minutely  upon  it. 

Mr.  Plana  remarks,  in  page  355  of  the  work  above-mentioned,  that   the   action  of  the 
fixed  stars  affects  the  mathematical  accuracy  of  the  equation  [1114], 

[4685g-]  ''^- '»  •  \/»  +  e'^. m'.\/a'-\-  kc.  =  constant  ; 

as  we  have  already  remarked  in  [11 146].  This  is  evident  ;  for,  if  we  increase  the  quantity 
e,  in  the  first  member,  by  the  expression  &e  [4669],  the  second  member  will  be  increased 
by  the  quantity, 

[4685?,,]  ■2f.5e  = ^^^ .  cos.a/.t-.s.n.(2:3  — 2t/),  nearly; 

which  destroys  the  constancy  of  the  second  member.  The  same  defect  exists  in  the 
equation  [1134  or  1155]. 


VI.xviii.§47.]  ACTION  OF  THE  FIXED  ST^VRS.  355 

It  is  easy  also,  to  satisfy  ourselves,  that  the  preceding  results  hold  good, 
relatively  to  those  planets  which  are  the  most  distant  from  the   sun.     Hence 
it  a|)pears,  that  the  action  of  the  stars  upon  the  planetary  system,  is  so  much      [4680] 
decreased,  by  reason  of  their  great  distance,  that  it  is  wholly  insensible. 

It  now  remains  to  compare  with  observations,  the  formulas  of  the 
planetary  perturbations,  given  in  this  book,  and  particularly  those  of  the 
two  great  inequalities  of  Jupiter  and  Saturn.  This  comparison  requires  too 
much  detail  for  the  limits  of  the  present  work;  we  shall,  therefore,  merely 
remark,  that  before  the  discovery  of  these  great  inequalities,  the  errors  of  the  ^ 

best  tables  sometimes  amounted  to  thirty-five  or  forty  minutes  ;  and  now  they 
do  not  exceed  a  minute.  Halley  had  concluded,  by  the  comparison  of  modern 
observations,  the  one  witli  the  other  ;  and  also,  by  comparing  the  modern  with 
the  ancient  observations,  that  Saturn's  motion  is  retarded,  and  Jupiter's 
accelerated,  from  age  to  age.  On  the  other  hand,  Lambert  ascertained,  from 
the  comparison  of  modern  observations  alone,  that  Saturn's  motion  was  then  [4088] 
accelerated,  and  Jupiter's  motion  retarded.  These  phenomena,  apparently 
opposed  to  each  other,  indicated,  in  ihc  motions  of  the  two  planets,  great 
inequalities  of  a  long  period,  of  which  it  was  important  to  know  the  laws  and  the 
cause.  By  submitting  to  analysis  their  mutual  perturbations,  I  discovered 
the  two  principal  inequalities  [4i34,  4492]  ;  and  perceived,  that  the 
phenomena,  observed  by  Halley  and  Lambert,  naturally  arise  from  them  ; 
and,  that  they  represent,  with  remarkable  accuracy,  both  ancient  and  modern 
observations.  The  magnitude  of  these  inequalities,  and  the  great  length  of 
the  period  of  revolution,  to  complete  v.'hich  requires  more  than  nine  hundred 
years,  depend,  as  we  have  seen,  on  the  nearly  commensurable  ratio  which 
obtains  between  the  mean  motions  of  Jupiter  and  Saturn.  This  ratio  gives 
rise  to  several  other  important  inequalities,  which  I  have  determined,  and  these 
inequalities  have  given  to  the  tables  the  precision  they  now  have.  The  same 
analysis,  being  applied  to  all  the  other  planets,  has  enabled  me  to  discover,  in 
their  motions,  some  very  sensible  inequalities,  which  have  been  confirmed  by 
observation.  I  have  reason  to  believe,  that  the  preceding  formulas,  computed 
with  particular  care,  will  give  a  still  greater  degree  of  precision  to  the  tables 
of  the  motions  of  the  planetary  bodies. 


IVrii-iS  cl' 

diflcit'iii 

ufilerà. 


[4693] 


SEVENTH    BOOK, 


THEORY   OF  TriE   MOON. 


The  theory  of  the  moon  has  difficulties  peculiar  to  itself,  arising  from 
the  magnitude  of  its  numerous  inequalities,  and  from  the  slow  convergency 
of  the  series  by  which  they  are  determined.  If  tlie  body  were  nearer  to 
the  earth,  the  inequalities  of  its  motion  would  be  less,  and  their  approximations 
more  converging,  But,  in  its  present  distance,  these  approximations  depend 
on  a  very  complicated  analysis;  and  it  is  only  by  a  very  particular  attention, 
and  a  nice  discrimination,  that  we  can  determine  the  influence  of  the 
successive  integrations,  upon  the  various  terms  of  the  expression  of  the 
disturbing  force.  The  selection  of  co-ordinates  is  not  unimportant  for  the 
[4692]  success  of  the  approximations.  The  sun's  disturbing  force  depends  on  the 
sines  and  cosines  of  the  moon's  elongation  from  the  sun,  and  on  its  multiples. 
Their  reduction  to  sines  and  cosines  of  angles,  depending  on  the  mean 
motions  of  the  sun  and  moon,  is  troublesome,  and  has  but  little  convergency, 
on  account  of  the  moon's  great  inequalities.  It  is,  therefore,  advantageous 
to  avoid  this  reduction,  and  to  determine  the  moon's  mean  longitude  in  a 
function  of  the  true  longitude,  which  may  be  usciul  on  several  occasions. 
We  may,  then,  if  it  be  required,  determine  accurately,  by  inverting  the  series, 
the  true  longitude,  in  a  function  of  the  mean  longitude.  It  is  in  this  way 
we  shall  consider  the  lunar  theory. 

To  arrange  conveniently  these  approximations,  we  shall  divide  the 
inequalities,  and  the  terms  which  compose  them,  into  several  orders.  We  shall 
consider  as  quantities  of  the  first  order,  the  ratio  of  the  sun's  mean  motion  to 
that  of  the  moon,  the  excentricity  of  the  orbit  of  the  moon  or  earth,  and  the 
inclination  of  the  moon's  orbit  to  the  ecliptic.  Thus,  in  the  expression  of  the 
mean  longitude,  in  a  function  of  the  true  longitude  [5574 — 5578],  the 
principal  term  of  the  moon's  equation  of  the  centre  is  of  the  first  order 
[5574].     The  second  order  includes  the  second  term  of  that  equation  :  the 


vil.  Introd.]  INTRODUCTION.  357 

reduction  to  the  ecliptic  ;  and  the  three  great  inequalities,  known  under 
the  names  of  variation,  erection,  and  annual  equation  [5575].  Tlie  ^  *'  ■' 
inequalities  of  the  third  order  are  fifteen  in  number  [5576].  The  present 
tables  contain  all  these  inequalities,  together  with  the  most  important  ones  of 
the  fourth  order;  and  it  is  on  this  account,  that  they  correspond  with  the 
observations  made  on  the  moon,  with  a  degree  of  accuracy  that  it  will  be 
difficult  to  surpass  ;  and  to  this  great  correctness  we  are  indebted  for  the 
important  improvements  in  geography  and  nautical  astronomy. 

The  object  of  this  book  is  to  shoio,  in  the  first  place,  that  the  law  of 
universal  gravity  is  the  only  source  of  all  the  inequalities  of  the  lunar 
motions;  and  then,  to  use  this  law  as  a  method  of  discovery,  to  perfect  the 
theory  of  these  inequalities,  and  to  deduce  from  them  several  important 
elements  of  the  system  of  the  ivorld  ;  such  as  the  secular  equations  of  the 
moon,  the  parallaxes  of  the  moon  and  sun,  and  the  oblateness  of  the  earth. 
A  judicious  choice  of  the  co-ordinates,  and  well  conducted  approximations, 
with  calculations  made  carefully,  and  verified  several  times,  ought  to 
give  the  same  results  as  those  derived  from  observation  ;  if  the  law  of 
gravity,  inversely  as  the  square  of  the  distance,  be  the  law  of  nature. 
We  have,  therefore,  endeavored  to  satisfy  these  conditions  ;  which  require  [4(i95] 
the  consideration  of  some  very  intricate  points  ;  the  neglect  of  which  is 
the  cause  of  the  discrepances,  that  have  been  observed  in  the  previously 
known  theories  of  the  moon.  It  is  in  these  points,  that  the  main  difficulty 
of  the  problem  consists.  We  may  easily  conceive  of  a  great  many 
diffijrent  and  new  methods  of  expressing  the  problem  by  equations  ;  but 
it  is  the  discussion  of  all  those  terms,  which  are  of  themselves  very  small, 
and  acquire  a  sensible  value,  by  the  successive  integrations,  which  constitutes 
the  important  and  difficult  part  of  the  process,  when  we  endeavor  to 
make  the  theory  agree  with  observation  ;  which  should  be  the  chief 
object  of  the  analysis.  We  have  determined  all  the  inequalities  of  the  first, 
second  and  third  orders,  and  the  most  important  ones  of  the  fourth  order, 
continuing  the  approximation  to  quantities  of  the  fourth  order  inclusively  ; 
and  retaining  those  of  the  fifth  order,  which  arise  in  the  calculation.  For 
the  purpose  of  comparing  this  analysis  with  observation,  w^e  may  observe, 
that  the  coefficients  of  Mason's  lunar  tables  are  the  result  of  the  comparison 
of  the  theory  of  gravity  with  eleven  hundred  and  thirty-seven  observations  [\g^m;-] 
of  Bradley,  made  between  the  years  1750  and  1760;  that  the  eminent 
VOL.  III.  90 


[4697] 


[4698] 


358  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

astronomer  Burg  has  rectified  these  tables,  by  means  of  more  than  three 
thousand  of  Maskelyne's  observations,  from  1765  to  1793;  and,  that  the 
corrections  he  has  made  are  small  ;  with  the  addition  of  nine  equations, 
indicated  by  the  theory.  The  tables  of  both  these  astronomers  are  arranged 
in  the  same  form  as  those  of  Mayer,  of  which  they  are  successive 
improvements  :  and  we  ought,  in  justice  to  this  celebrated  astronomer,  to 
observe,  that  he  was  not  only  the  first,  who  constructed  lunar  tables, 
sufficiently  correct  to  be  used  in  the  solution  of  the  problem  of  finding  the 
longitude  at  sea,  but  also,  that  Mason  and  Burg  have  deduced,  from  his 
theory,  the  methods  of  improving  their  tables.  The  arguments  are  made  to 
depend  on  each  other,  in  order  to  decrease  the  number  of  them.  We  have 
reduced  them,  Avitli  particular  care,  to  the  form  which  is  adopted  in  the 
present  theory  ;  that  is,  to  sines  and  cosines  of  angles,  increasing  in  proportion 
to  the  moon's  true  longitude.  By  comparing  these  results  with  the 
coefficients  of  the  present  theory,  we  have  the  satisfaction  of  perceiving, 
that  the  greatest  difference,  which,  in  Mayer's  theory,  one  of  the  most 
accurate  heretofore  published,  amounts  to  nearly  one  hundred  centesimal 
seconds  [=32',4],  is  here  reduced  to  thirty  [9',8],  relative  to  the  tables 
of  Mason,  and  to  less  than  twenty-six  centesimal  seconds  [^8',3],  relative 
to  the  still  more  accurate  tables  of  Burg.  We  could  diminish  this  difference, 
by  noticing  quantities  of  the  fifth  order,  which  have  some  influence,  as  may 
be  known  by  inspecting  the  terms  of  this  kind  already  calculated.  This  is 
proved  by  the  computation  of  the  two  inequalities  [5286'",  &c.],  in  which  we 
have  carried  on  the  approximation  to  quantities  of  the  fifth  order.  The 
present  theory  agrees  yet  better  with  the  tables,  relative  to  the  motion  in 
latitude.  The  approximations  of  this  motion  are  more  simple  and  converging 
than  those  of  the  motions  in  longitude  ;  and  the  greatest  difference  between 
the  coefficients  of  my  analysis  and  those  of  the  tables,  is  only  six  centesimal 
seconds  [=  l',9],  so  that  we  may  consider  this  part  of  the  tables  as  being 
founded  upon  the  theory  itself.  As  to  the  third  co-ordinate  of  the  moon,  or 
[4700]  its  parallax,  we  have  preferred,  without  hesitation,  to  form  the  tables  by  the 
theory  alone,  which,  on  account  of  the  smallness  of  the  inequalities  of  the  lunar 
parallax,  must  give  them  more  accurately  than  they  can  be  olitained  by 
observation.  The  differences  between  the  results  of  the  present  theory  and 
those  of  the  tables,  express,  therefore,  the  differences  between  this  theory  and 
that  of  Mayer,  which  has  been  adopted  by  Mason  and  Burg.  These 
differences  are  so  small  that  they  are  hardly  deserving  of  notice  ;  but,  as  the 


[4699] 


vil.  Introil.]  INTRODUCTION.  359 

present  theory  agrees  better  with  observation  than  Mayer's,  in  the  motion  in 
longitude,  there  is  also  reason  to  believe,  that  it  possesses  the  same  advantage         '    ' 
relative  to  the  inequalities  in  the  parallax. 

The  motions  of  the  perigee  and  nodes  of  the  lunar  orbit,  afford  also  a 
method  of  verifying  the  law  of  gravity.  In  the  first  approximation  to  the 
value  of  the  motion  of  the  perigee,  by  the  theory  of  gravity,  it  was  found, 
by  mathematicians,  only  one  half  of  what  it  was  known  to  be,  by  observation  ; 
and  Clairaut  inferred,  from  this  circumstance,  that  we  must  modify  the  law  of  r4702'| 
gravity,  by  adding  to  it  a  second  term.  But  he  afterwards  made  the  important 
remark,  that  by  continuing  the  approximations  to  terms  of  a  higher  order,  the 
theory  would  be  found  to  agree  nearly  with  observation.  The  motion, 
deduced  from  the  present  analysis,  differs  from  the  actual  motion  only  a  four 
hundredth  part  [5231 J  ;  the  difference  is  not  a  three  hundred  and  fiftieth  part  ^ 

in  the  motion  of  the  nodes  [5233']. 

Hence  it  incontestabhj  follows,  that  the  laiv  of  universal  gravitation  is  the 
sole  cause  of  the  lunar  inequalities.  Now,  if  we  consider  the  great  number 
and  extent  of  these  inequalities,  and  the  proximity  of  the  moon  to  the  earth, 
we  must  be  satisfied,  that  it  is,  of  all  the  heavenly  bodies,  the  best 
adapted  to  confirm  this  great  law  of  nature,  as  well  as  to  show  the  power  of  [47041 
analysis,  that  wonderful  instrument,  without  the  aid  of  which  it  would  be 
impossible  for  the  human  mind  to  penetrate  into  so  complicated  a  theory,  and 
that  can  be  used,  as  a  means  of  discovery,  as  sure  as  by  direct  observation. 

Among  the  periodical  inequalities  of  the  moon's  motion  in  longitude,  that 
which  depends  on  the  simple  angular  distance  of  the  moon  from  the  sun  is      [1705] 
important,  on  account  of  the  great  light  it  throws  on  the  sun's  parallax.     It 
has  been  determined  by  the  theory  ;    noticing  quantities  of  the  fifth  order, 
and  also  the  perturbation  of  the  earth  by  the  moon,  which  are  indispensable      [4'OC] 
in  this  laborious  research.     Burg  found  this  inequality  to  be   122,38,  by  the 
comparison  of  a  very  great  numl)er  of  observations.     If  we  put  this  equal  to 
the  result  by  the  theory,  we  obtain  8',56,  for  the  sun's  mean  parallax  ;  being      [4707] 
the  same   as  several   astronomers  have  found,  from  the  last  transit  of  Venus 
over  the  sun  [5586]. 

An  inequality,  which  is  not  less  important,  is  that  which  depends  on  the 
longitude  of  the  moon's  node.  Mayer  discovered  it  by  observation,  and 
Mason  fixed  it  at  7',7  ;  but,  as  it  did  not  appear  to  depend  on  the  theory      [4708] 


360  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

of  gravity,  it  was  neglected  by  most  astronomers.  A  more  thorough 
examination  of  this  theory  led  me  to  the  discovery,  that  its  cause  is  the 
oblateness  of  the  earth.  Burg  found  it,  by  a  great  number  of  Maskelyne's 
[4709]  observations,  to  be  6,8  ;  which  corresponds  to  an  oblateness  of  -a-ëi.-ôT 
[5593]. 

We  may  also  determine  this  oblateness,  by  means  of  an  inequality  in  the 
moon's  motion  in  latitude  ;    which  I   discovered  also  by  the   theory  ;    and 

[4710]  which  depends  on  the  sine  of  the  moon's  true  longitude.  It  is  the  result  of 
a  nutation  in  the  lunar  orbit,  produced  by  the  action  of  the  terrestrial 
spheroid,  and  corresponds  to  that  produced  by  the  moon  in  our  equator  ;  so 
that  the  one  of  these  nutations  is  the  reaction  of  the  other  :  and,  if  all 
the  particles  of  the  earth  and  moon  were  firmly  connected  together,  by 
inflexible  right  lines,  void  of  mass,  the  whole  system  Avould  be  in  equilibrium 
about  the  centre  of  gravity  of  the  earth,  in  virtue  of  the  forces  producing 
these  two  nutations  :  the  force,  acting  on  the  moon,  compensating  for 
its  smallness,  by  the  length  of  the  lever  to  which  it  is  attached.  We 
may  represent  this  inequality  in  latitude,  by  supposing  the  lunar  orbit,  instead 
of  moving  uniformly  on  the  ecliptic,  with  a  constant  inclination,  to  move, 
with  the  same  conditions,  upon  a  plane  but  little  inclined  to  the  ecliptic,  and 
which  always  passes  through  the  equinoxes,  between  the  ecliptic  and 
equator  :  a  phenomenon  which  occurs  in  the  theory  of  Jupiter's  satellites, 
in  a  still    more    striking    manner.       Thus,    this    inequality    decreases    the 

[4712]  inclination  of  the  moon's  orbit  to  the  ecliptic,  when  the  ascending  node 
of  that  orbit  coincides  with  the  vernal  equinox.  This  inclination  is 
increased,  when  the  ascending  node  coincides  with  the  autumnal  equinox, 
which  was  the  case  in  1755;  in  consequence  of  which,  the  inclination,  as 
it  was  found  by  Mason,  from  1750  to  1760,  is  too  great.  This  point  has 
been  determined  by  Burg,  by  observations  made  during  a  much  longer 
interval,  noticing  the  preceding  inequality  ;  and  he  has  found  the  inclination 

[^^^"^1  to  be  less,  by  3 ,7.  At  my  request,  this  astronomer  has  undertaken  to 
determine  the  coefficient  of  this  inequality,  by  a  very  great  number  of 
observations  ;  and  he  has  found  it  to  be  equal  to  —  8".     The  oblateness  of 

[4714]  the  earth,  deduced  from  it,  is  ^^t.t  [5602],  being  very  nearly  the  same 
as  that  which  is  computed  from  the  preceding  inequality  of  longitude, 
Thus,  the  moon,  by  the  observation  of  her  motions,  renders  sensible  to 
modern  astronomy  the  ellipticity  of   the  earth,  whose  roundness  was  made 


VII.  Introd.]  INTRODUCTION.  361 

kiioAvu  to  the  early  astronomers  by  her  eclipses.  The  experiments  on  the 
pendulum  seem  to  indicate  a  less  oblateness,*  as  we  have  seen  in  the  third 
book.  Tills  difference  may  depend  on  the  terms  by  which  the  earth  varies 
from  an  elliptical  figure  ;  m  hich  may  have  some  small  effect  in  the  expression 
of  the  length  of  the  pendulum,  but  is  wholly  insensible,  at  the  distance  of 
the  moon. 

The  two  preceding  inequalities  deserve  every  attention  of  observers  ; 
because  they  have  the  advantage  over  geodetical  measures,  in  giving  the 
oblateness  of  the  earth,  in  a  manner  which  is  less  dependant  on  the 
irregularities  of  its  figure.  If  the  earth  were  homogeneous,  these  inequalities 
would  be  much  greater  than  they  are  found  to  be  by  observation.  They  l"*'^^! 
concur,  therefore,  with  the  phenomena  of  the  precession  of  the  equinoxes, 
and  the  variation  of  gravity  at  the  surface  of  the  earth,  to  exclude  its 
homogeneity.  It  results  also,  that  the  moori's  gravity  towards  the  earth,  is 
composed  of  the  attractions  of  all  the  particles  of  the  earth;  ivhich  furnishes 
another  proof  of  the  attraction  of  all  the  particles  of  matter. 

Theory  combined  wàth  experiments  on  the  pendulum,  the  geodetical 
measures,  and  the  phenomena  of  the  tides,  make  the  constant  term  of  the 
expression  of  the  moon's  parallax  less  than  by  Mason's  tables.  It  differs  but  [4716] 
very  little  from  that  which  Burg  computed  from  a  great  number  of  observations 
of  the  moon,  of  eclipses  of  the  sun,  and  of  occultations  of  stars  by  the  moon. 
It  is  only  necessary  to  decrease  a  little  the  mass  of  the  moon,  which  was 
determined  by  the  phenomena  of  the  tides,  to  make  this  constant  term 
coincide  with  the  result  of  that  skilful  astronomer.  This  diminution  is  also  [4717] 
indicated  by  the  observations  of  the  lunar  equation  of  the  solar  tables,  and 
by  the  nutation  of  the  earth's  axis.  This  seems  to  prove,  that  in  the  port  of 
Brest,  the  ratio  of  the  moon's  action  on  the  tides  to  that  of  the  sun,  is 
sensibly  increased  by  local  circumstances.  Future  observations  of  all  these 
phenomena  will  remove  this  slight  degree  of  uncertainty. 

One   of  the    most  interesting   results    of   the    theory  of   gravity,   is   the 
knowledge    of    the    secular    inequalities    of    the    moon.       Ancient   eclipses 


*  (2753)     Later  and  more  accurate  observations  give  a  different  result,  as  may  be  seen,     [4715a] 
by  referring  to  [201  7ji,  2056î,  &:c.]. 
VOL.  III.  91 


[4718] 


362  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[4719] 


indicated,  in  the  moon's  mean  motion,  an  acceleration  ;  the  cause  of  which 
was  sought  for  a  long  time  in  vain.  Finally,  I  discovered,  by  the  theory, 
that  it  depends  on  the  secular  variations  of  the  excentricity  of  the  earth's 
orbit.  The  same  cause  decreases  the  mean  motions  of  the  perigee  and  nodes 
of  the  moon,  while  her  mean  motion  is  increased  ;  so  that  the  secular 
equations  of  the  mean  motions  of  the  moon,  the  perigee  and  the  nodes, 

[4720]  are  always  in  the  ratio  of  the  numbers  1,  3  and  0,74  [5235].  Future  ages 
ivill  develop  these  great  inequalities,  which  are  periodical,  like  the  variations 
of  the  excentricity  of  the  eartli's  orbit,  upon  which  they  depend.  These 
will  finally  produce  variations  which  amount,  at  the  least  estimate,  to 
a    fortieth  part  of   the   circumference   [d''],  in   the  moon's   secular  motion; 

[4721]  and  to  a  twelfth  of  the  circumference  [30''],  in  that  of  the  perigee. 
Observations  have  already  confirmed  these  secular  inequalities  in  a 
remarkable  manner.  The  discovery  of  them  induced  me  to  believe,  that 
we  must  diminish,  by  fifteen  or  sixteen  centesimal  minutes,  the  present 
secular  motion  of   the  moon's  perigee,  which  astronomers  had  determined, 

[4722]  by  comparing  modern  observations  with  ancient  ones.  All  the  observations, 
which  have  been  made  during  the  last  century,  have  put  beyond  doubt,  this 
result  of  analysis.  We  see,  in  this,  an  example  of  the  manner  in  which  the 
phenomena,  as  they  are  developed,  throw  light  upon  their  true  causes.     When 

[4723]  the  acceleration  of  the  moon's  mean  motion  only  was  known,  it  could  be 
attributed  to  the  resistance  of  the  ether,  or  to  the  successive  transmission  of 
gravity  ;  but  analysis  shows  us,  that  both  these  causes  produce  no  sensible 
alteration,  either  in  the  mean  motion  of  the  nodes,  or  in  that  of  the  lunar 
perigee  :  this  is  a  sufficient  reason  for  rejecting  them,  even  if  we  were 
ignorant  of  the  true  cause.  The  agreement  of  the  theory  with  observations, 
proves,  that  if  the  moon's  mean  motion  is  affected  by  any  causes,  besides  the 
action  of  gravity,  their  influence  is  very  small,  and  is  not  yet  perceptible. 


[4724] 


This  agreement  establishes,  with  certainty,  the  constancy  of  the  duration 
of  a  day  ;  which  is  an  essential  element  in  all  astronomical  theories.  If 
this  duration  were  now  one  hundredth  part  of  a  centesimal  second  [or  0',864] 

[4725]  more  than  in  the  time  of  Hipparchus,  the  duration  of  the  present  century 
would  be  greater  than  in  his  time,  by  365i  centesimal  seconds  [or  315',576]. 

[4725]  In  this  interval,  the  moon  would  describe  an  arch  of  173',2,  and  the  present 
mean  secular  motion  of  the   moon,  would   appear  to   be   augmented  by  the 


VII.  Introd.]  INTRODUCTION.  363 

same  quantity.  This  would  add  4,4*  to  the  secular  equation,  which  is  [472G] 
Ibuiid,  by  the  theory,  to  be  10',1 81621  [5543],  in  the  first  century  after  the 
year  1750.  This  augmentation  is  incompatible  with  the  best  observations, 
which  do  not  permit  us  to  suppose,  that  the  secular  equation  can  exceed,  by 
V,62,  the  result  of  the  analysis  [5543].  We  may,  therefore,  conclude,  that 
the  duration  of  the  day  has  not  varied  a  hundredth  part  of  a  centesimal  [4727] 
second,  since  the  time  of  Hipparchus  ;  which  confirms  what  has  been  found 
a  priori,  in  book  v.  ^  12  [3347,&.c.],by  the  discussion  of  all  the  causes  which 
could  alter  it. 

To  omit  nothing  which  can  have  an  influence  on  the  moon's  motion, 
we  have  considered  the  direct  action  of  the  planets  upon  this  satellite,  and 
have  found,  that  it  is  of  very  little  importance.  But  the  sun,  by  transmitting 
to  the  moon  the  action  of  the  planets  on  the  elements  of  the  earth's  orbit, 
renders  their  influence  on  the  lunar  motions  very  remarkable,  and  makes  it  much  [4728] 
greater  than  on  the  elements  themselves  ;  so  that  the  secular  variation  of  the 
excentricity  of  the  earth's  orbit  is  much  more  sensible,  in  the  moon's  motion, 
than  in  the  earth's.  It  is  in  this  manner,  that  the  moon's  action  on  the  earth, 
which  produces,  in  the  earth's  motion,  the  inequality  known  by  the  name  of 
the  hmar  equation,  is,  if  it  may  be  so  expressed,  reflected  back  to  the  [4729] 
moon,  by  means  of  the  sun,  but  decreased  in  nearly  the  ratio  of  five  to 
nine  [5226].  This  new  consideration  adds  some  terms  to  the  action  of  the 
planets  on  the  moon,  which  are  of  more  importance  than  those  depending 
on  their  direct  action.  We  have  investigated  the  principal  lunar  inequalities, 
resulting  from  the  direct  and  indirect  actions  of  the  planets  upon  the  moon  ;      [4/30] 

*  (2754)  If  we  neglect  tlie  term  of  the  secular  equation  [5543],  depending  on  P,  and 
put  (7=10',  181621,  we  may  represent  the  moon's  mean  motion,  in  i  centuries  after  1750, 
by     ni -{-ai-.     If  we  substitute  in  this  successively,    i^  —  J,    i  =  -j-|,    and  take  the  "' 

difference  of  the  two  results,  it  will  be  found  equal  to  n,  whicii  must,  therefore,  represent 
the  motion  between  1700  and  1800.  In  like  manner,  by  putting  successively  i=  —  20, 
i^ — 19,  and  taking  the  difference  of  the  two  results,  we  get  n  —  39  a,  for  the  motion  in  the 
century  included  between  the  years  250  and  150  before  the  Christian  era.  The  difference 
of  these  two  results  39  a,  represents  the  augmentation  of  the  secular  motion  between  these 
two  epochs;  and,  if  this  quantity  were  increased  173%2,  as  in  [4725'j,  we  must  increase  the  '  '^■' 
value  of  a  by  ^VX  173',2  =  4%4,  as  in  [4726]. 


[4720i] 


3^  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

and,  if  we  take   into  view  the  accuracy  to  which  the  lunar  tables  have  been 
carried,  it  must  be  considered  useful  to  introduce  these  inequalities. 

The  moon's  parallax,  the  excentricity  and  the  inclination  of  the  lunar 
orbit  to  the  apparent  ecliptic,  and,  in  general,  the  coefficients  of  all  the  lunar 
inequalities,  are  likewise  subjected  to  secular  variations  ;  but,  up  to  the 
[4731]  present  period,  they  are  hardly  sensible.  This  is  the  reason  why  we  find 
now,  the  same  inclination,  that  Ptolemy  obtained  from  his  observations  ; 
although  the  obliquity  of  the  ecliptic  to  the  equator  has  sensibly  decreased 
since  the  time  of  that  astronomer;  so  that  the  secular  variation  of  the  obliquity 
affects  only  the  moon's  declination.  However,  the  coefficient  of  the  annual 
equation,  having  for  a  factor,  the  excentricity  of  the  earth's  orbit,  its 
variation  is  sufficiently  great  to  be  noticed,  in  computing  ancient  eclipses. 


[4732] 


The  numerous  comparisons,  which  Burg  and  Bouvard  have  made,  of  Mason's 
tables,  with  the  observations  of  the  moon  ;  at  the  end  of  the  seventeenth 
century,  by  LaHire  and  Flamsteed  ;  in  the  middle  of  the  eighteenth  century, 
by  Bradley  ;  and  the  uninterrupted  series  of  observations  of  Maskelyne, 
from  the  time  of  Bradley  to  the  year  1800,  give  a  result  which  was  wholly 

[4733]  unexpected.  The  observations  of  LaHire  and  Flamsteed,  being  compared  witli 
those  of  Bradley,  indicate  a  secular  motion,  exceeding  by  fifteen  or  twenty 
centesimal  seconds,  that  which  is  inserted  in  the  third  edition  of  La  Lande's 
astronomy  ;  which,  in  a  hundred  Julian  years,  exceeds  a  whole  number  of 

[4734]  revolutions,  by  307'^53"'12^  Bradley's  observations,  being  compared  with 
the  last  ones  of  Maskelyne,  give,  on  the  contrary,  a  smaller  secular  motion, 
by  at  least  one  hundred  and  fifty  centesimal  seconds.  Lastly,  the  observations 

[4735]  made  within  fifteen  or  twenty  years,  prove,  that  the  diminution  of  the  moon's 
motion  is  now  decreasing.  Hence,  it  becomes  necessary  to  vary  incessantly 
the  epochs  of  the  tables  ;  and  it  is  an  object  of  importance  to  correct  this 
imperfection.    This  evidently  indicates  the  existence  of  one  or  more  unknown 

^  ^  inequalities  of  a  long  period,  which  the  theory  alone  can  point  out.  By  a 
careful  examination,  I  have  not  been  able  to  discover  any  such  inequality, 
depending  on  the  action  of  the  planets.  If  there  were  one  in  the  rotation 
of  the  earth,  it  could  be  perceived  in  the  moon's  mean  motion,  and  might 
introduce  the  observed  anomalies  :  but  an  attentive  examination  of  all  the 
causes  which  can  alter  the  rotation  of  the  earth,  has    more  fully  convinced 

[4737]      ^^^  ^j^^^  j^g  variations    are    insensible.     Returning    back,  therefore,  to  the 


VII.  Intiod.]  INTRODUCTION.  S6b 

exaniin;itioii  of  the  sun's  action  on  the  moon  ;  I  have  discovered,  that  this 

action  produces  an  inequality,  whose  argument  is  double  the  longitude  of  the 

node  of  tiie  lunar  orbit,  jdus  the   longitude  of  its  perigee,  minus  three  times 

the  longitude  of  the   sun's  perigee.     This   inequality,  whose  period  is    184      [4738] 

vears,  depends  on  the  products  of  these  four  quantities,  namely  ;  the  square 

of  the  inclination  of  the  moon's  orbit  to  the  ecliptic  ;  tlie  excentricity  of  that 

orbit  ;  the  cube  of  the   excentricity  of  the   sun's   orbit,  and  the  ratio  of  the 

sun's  parallax  to  that  of  the  moon.      Hence  it  would  seem,  that  it  ought  to      [4739] 

be  insensible  ;   but  the  small  divisors  it  acquires  by  integration,  may  render  it 

sensible,  especially,  if  the  most  important  terms,  of  wliich   it   is  composed, 

are  affected  with  the  same  sign.     It  is  very  difficult  to  obtain  its  coefficient 

by  the  theory,  on  account  of  the   great  number  of  terms,  and  the  extreme     [4740] 

difficulty  of  appreciating  them  ;  the  difficulty  being  much  greater  in  this  than 

in  the  other  inequalities   of  the  moon.     This  coefficient  has,  therefore,  been 

ascertained  by  means  of  the  observations  made  during  the  last  century  ;  and 

I   have  found  it  to  be  nearly  equal  to  15',39.      Its  introduction  in  the  tables      [4741] 

must  change  the  epoch  and  mean  motion  ;  and  I  have  also  found,  that  we  must 

decrease,   by    31'',964,    the    mean    secular  motion,   in  the   third    edition  of     [4742] 

LaLande's  astronomy,  and   have    determined  the   following  formula,  which 

must    be    applied    to    the  mean  longitude  given  by  these  tables,   the   epoch      [4743] 

of  which,  in   1750,  is   188"  17'"  14',6  ;  Equnt,,,,, 

nf  184 

Correction  of  moon's  mean  long.  =  — 12',78  —  31 ',964 .  i  +  15',39  .  ûn.E  ;     T4744] 

i  being  the  number  of  centuries  elapsed  since  1750,  and  E  the  double  of  the 
longitude  of  the  node  of  the  lunar  orbit,  plus  the  longitude  of  its  perigee,  [47451 
minus  three  times  the  longitude  of  the  sun's  perigee.  This  formula  represents, 
with  remarkable  precision,  the  corrections  of  the  epochs  of  those  tables, 
which  have  been  determined,  by  a  very  great  number  of  observations,  for  the 
six  epochs  of  1691,  1756,  1766,  1779,  1789  and  1801.  By  a  most  scrupulous 
examination  of  the  theory,  I  have  not  been  able  to  discover  any  other  lunar 
inequality  Avith  a  long  period  ;  hence,  it  appears  to  me  certain,  that  the  [4746] 
anomalies  observed  in  the  mean  motion  of  the  moon,  depend  on  the 
preceding  inequality  ;  and  I  do  not  hesitate,  therefore,  to  propose  it  to 
astronomers,  as  the  only  means  of  correcting  these  anomalies.* 

*  (2755)     It  has  not  been  found  necessary  to  introduce  this  equation  in  the  new  tables 
of  Damoiseau,  pviblished  in  1824;    since  the  elements  lie  has  used,  give  very  nearly  the     L4<46a] 
VOL.  III.  92 


366  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

We  see,  by  this   exposition,  how  many  interesting  and  delicate  elements 
hai^e  been  deduced,  by  analysis,   from  observations  of  the  moon,  and  how 
[4747]      important  it  is  to  multiply  and  improve   them.      Since,   by  the   greatness   of 
their  number,  and  by  their  correctness,  we  may  more  and  more   confirm  the 
various  results  of  analysis. 

The   error  of  the  tables  formed  from  the  theory,  which  is  given  in  this 
book,  does  not  exceed  a  hundred  centesimal  seconds,  except  in  very  rare  cases; 

[4748]  therefore,  these  tables  will  give,  with  sufficient  accuracy,  the  longitude  at 
sea.  It  is  very  easy  to  reduce  them  to  the  form  of  Mayer's  tables  ;  but,  as 
in  the  problem  of  the  longitude,  it  is  proposed  to  find  the  time  corresponding 

[4749]  to  an  observed  longitude  of  the  moon,  there  is  some  advantage  in  reducing 
into  tables,  the  expression  of  the  time  in  a  function  of  the  apparent 
longitude.  Considering  the  extreme  complication  of  the  successive 
approximations,  and  the  correctness  of  modern  observations,  the  greatest  part 
of  the  moon's  inequalities  have  heretofore  been  better  determined  by 
observations  than  by  analysis.  Thus,  by  deriving  from  the  tlieory  those 
coefficients  which  it    gives  with    accuracy,  and    also  the  forms  of  all   the 

[4750]  arguments  ;  then  rectifying,  by  the  comparison  of  a  great  number  of 
observations,  the  coefficients  which  it  gives  by  approximations,  with 
some  degree  of  uncertainty  :  we  must  finally  obtain  very  accurate  tables. 
This  is  the  method  which  has  been  used  with  success  by  Mayer  and 
Mason,  and  lately  by  Burg,  who,  by  pursuing  it,  and  profiting  by  the 
late  improvements  in  the  lunar  theory,  has  constructed  tables,  whose 
greatest  errors  fall  short  of  forty  centesimal  seconds.  However,  it  would 
be  useful,  for  the  perfection  of  astronomical  theories,  if  all  the  tables 
^^^^^^  could  be  derived  solely  from  the  principle  of  universal  gravity;  without 
borrowing  from  observation  any,  except  the  indispensable  data.  1  am 
induced  to  believe,  that  the  following  analysis  leaves  but  little  wanting 
to  procure  this  advantage  to  the  lunar  tables  ;  and  that,  by  carrying  on 
farther  the  approximations,  we  may  soon  obtain  the  required  degree  of 
correctness,  at  least,  as  it  respects  the  periodical  inequalities  ;  for,  however 
great  the  accuracy  of  the  calculations  may  be,  the  motions  of  the  nodes  and 


same  mean  longitudes,  at  the  epochs   1756,    1770,  1801   and    1812,  as  Burckhardt  has 
deduced  from  the  observations  made  in  that  interval. 


VII.  Intiod.]  INTRODUCTION.  367 

perigee  will  always  be  best  determined  by  observation.*  [4752] 


*  ('2756)  Since  the  publication  of  tliis  volume,  two  very  important  works  on  the  lunar 
theory  have  been  published  ;  the  one  by  Baron  Damoiseau,  in  the  first  volume  of  the 
Mémoires  présentés  par  divers  sai'ans  à  F  Académie  Royale  des  Sciences  ;  the  other  by 
Messrs.  Plana  and  Carlini.  We  shall  have  occasion  to  speak  of  these  works  in  the  notes  L^'^^"] 
on  this  book,  and  shall  now  merely  remark,  that  the  object  of  them  is  to  carry  on  the 
approximation  to  such  a  degree  of  accuracy,  as  to  be  able  to  deduce  all  the  inequalities  from 
the  theorv  alone. 


368  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


CHAPTER    I. 

INTEGRATION  OF  THE  DIFFERENTIAL  EOUATIONS  OF  THE  MOON'S  MOTION. 

1.     Resuming  the  differential  equations  [525],  we  shall  put  them  under 
the  following  forms,* 

[4753]  dt=  "^^ 


General 


"•'••\/'  +  ^/(^?)-S' 


dv 


1    /dq\       s     fdq 


h^u'\du)  h^w^     '\ds 

In  these  equations,  t  denotes  the  time,  and  we  have,  as  in  [499',  397]  ; 
M-\-  m        m',  (x  .■?/+  y  ij'-\-  z  z')  m! 


(L) 


[4756]  Q  = 


i/(x'-xy-{-(y'-yr+(z'-zr 


*  (2757)     The  equation  [4753]  is  the  same  as  the  first  of  [525],  and  if  we  multiply 
the  other  two  equations  [525]  by 

they  willbecome  as  in  [4754,  4755]. 


VII.  i.  §1.]  GENERAL  DIFFERExNTIAL  EQUATIONS.  369 

M  is  the  mass  of  the  earth  ;  [4757] 

m  the  mass  of  the  moon  ;*  [4757'] 

m'  the  mass  of  the  sun  ;  [4757"] 

T,    w,    ~,  the  rectangular  co-ordinates  of  the  moon,  referred  to  the  centre  of 

[47581 

gravity  of  the  earth,  and  to  the  ecliptic  of  a  given  epoch,  taken  as 

^  ,       ,  Symbols. 

a  fixed  plane  ; 

x,  y',  -',  the  rectangular  co-ordinates  of  the  sun,  referred  to  the  same  centre  [4758'] 

and  plane  ; 

r  the  radius  vector  of  the  moon  ;  [4759] 

r*  the  radius  vector  of  the  sun  ;  [4759] 

s  the  tangent  of  the  moon's  latitude  above  the  fixed  plane  ;  [4759"] 

-  the  projection  of  the  moon's  radius  vector  r,  upon  the  fixed  plane  ;      [47G0] 

V  the  angle  formed  by  this  projection  of  r  and  the  axis  of  x  ;  [4760'] 

h^  a  constant  quantity  [518 — 519],  depending  chiefly  on  the  moon's    [47G0"] 
distance  from  the  earth  [4825,  &c.]. 

In  the  value  of  Q  [4756],  the  earth  and  moon  are  supposed  to  be  spherical. 
To  obtain  the  true  value,  corresponding  to  the  actual  forms  of  these  bodies, 
we  shall  observe,  that,  by  the  properties  of  the  centre  of  gravity,  we  must  ^  '  J 
transfer  to  the  moon's  centre  of  gravity  the  following  forces  ;  first,  all  the 
forces  by  which  each  of  its  particles  is  urged  by  the  action  of  the  particles  of 
the  earth,  and  divide  the  sum  by  the  whole  of  the  moon's  mass  ;  second,  the 
force  by  which  the  centre  of  gravity  of  the  earth  is  urged,  by  the  moon's 
action,  taking  it  in  a  contrary  direction.  This  being  jjremised,  it  is  evident, 
that  (131  being  a  particle  of  the  earth,  and  dm  a  particle  of  the  moon,  whose 
distance  from  the  particle  dM  is  /,  we  shall  have  the  forces  by  which  the 
moon's  centre  of  gravity  is  urged,  in  its  relative  motion  about  the  earth,  by 
means  of  the  ])artial  differentials  of  the  double  integral, f 

(M+rn)        ^  dM.dm 
Mm       -^-^         /       ' 


*  (2758)  This  value  of  to  is  used  in  the  two  first  sections  of  this  book  ;  but  its 
signification  is  changed  in  [4793],  so  that,  in  the  rest  of  the  book,  7nt  represents  the  sun's 
mean  motion. 


[4762] 


[4762'] 


t  (2759)     If  we  substitute,  in  [455],  the  value  of  dJ\l  [452],  also 
VOL.  III.  93 


370  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

taken  relatively  to  the  co-ordinates  of  the   moon's  centre.     Therefore,  we 

[4764]     must  substitute  this  function  for ,     in   the  expression  of  Q  [4756]. 

If  the  moon  were  spherical,  we  might  suppose  the  whole  mass  to  be  collected 
in  the  centre  of  gravity  [470'"]  ;  and  then,  by  putting  V  equal  to  the  sum  of 
[4765]     the  quotients,  formed  by  dividing  each  particle  of  the  earth  by  its  distance 
from  the  moon'' s  centre,  we  shall  have  [4767«], 

[4766]  ^  ff ^^m.V. 


[4763a]  f  =  \/\{=o'-^f+{y'-yf  +  {^-zf]      [455«],     it  becomes,      F=:/y; 

and  then,  the  corresponding  force  of  the  body  M  on  the  particle  dm,  in  the  direction  — x, 

—  )     [455'].       This    accelerative  force,  acting  on   the  single 

particle  dm,  is  to  be  decreased  in  the  ratio  of  dm  to  m,  to  obtain  the  corresponding  effect 

[47636]    Qp  {]jg  whole  body  m,  of  which  it  forms  a  part  ;  by  which  means  it  becomes       —  f  — — . 

Integrating  this,  so  as  to  include  all  the  particles  dm,  of  which  the  body    m   is  composed, 

it  becomes,- 

pdm    ^  dM  1    ^-dM.dm 

[47636']  J  —  J    ^^         O'"'         »^./  ^^        ' 

which  represents  the  value  of  V,  to  be  used  in  finding  the  accelerative  force  of  the  body  m, 

from  the  attraction  of  the  body  M.     If  we  change    m,    M    into    M,    m  respectively,  we 

shall  get     —  Cr '- — • ,     for  the  value  of  V,  to  be  used  in  finding  the  accelerative  force 

of  the  body  M,  from  the  attraction  of  the  body  m.     Adding  these  two  parts  together,  we 

[4763c]    obtain  the  complete  value  of  F=  T- +  ^  j  .yy '——,     corresponding    to    the     whole 

accelerative  force  of  m  towards  M,  supposing  M  to  be  at  rest.      This  is  easily  reduced  to 

the  form  [4763]  ;  and  its  partial  differentials,  relative  to  the  co-ordinates  x,  y,  z,  give  the 

r -«/.<% .,     accelerative  forces  parallel  to  those  co-ordinates  respectively.    Now,  when  the  bodies  M,  m 
[4763a] 

are  spherical,  these   accelerative  forces      -— 7-,     -—,     -—^,       are    represented    by    the     ^ 

[4763rf']    partial  differentials  of  Q,  taken  relatively  to  x,  y,  z  [499],  retaining  in    Q  [4756]   only 

the    term       Q^^=  ",     which  is  independent  of  the  disturbing  mass    m' .      Therefore, 

r 

[4763e]    to  notice  the  non-spherical  forms  of  the  bodies  M,   m,    we  have  only   to  substitute  the 
expression  [4763],  m  the  place  of  ,     in  the  function  Q  [4756]. 


VII.  i.  §  1]    EFFECTS  OF  THE  OBLATENESS  OF  THE  EARTH  AND  MOON.        371 
*  V  would  be  equal  to     —     if  the  earth  were  spherical  ;  hence,  if  we  put 

ôV=  V ;  [4767] 

m,&V  will  be  the  part  of  the  integral  ff ^— ,     depending  on  the    non-      [4768] 

sphericity  of  the  earth.  In  like  manner,  if  the  earth  be  supposed  spherical, 
and  we  put  V  equal  to  the  sum  of  the  quotients,  formed  by  dividing  each 
particle  of  the  moon  by  its  distance  from  the  centre  of  gravity  of  the  earth, 
we  shall  have, 

rr  ^J^-^^  ^  M.V;  [4770] 


[4769] 


and  if  we  put 


m 


6  F  =  V ,  [4770'] 


r 


M.  sV  will  be  the  part  of  the  integral    ff  — - — ,     depending  on  the  non-     [4771] 
sphericity  of  the  moon  ;  hence  we  shall  have,  very  nearly,! 

^TT —  •  /  / ? =  ■ h  (M4-m)  .  {  ^Ti  -\ ■  >  .  [4772] 

Mm      ^-^         f  r  ^       '      ■'     \  M        in    S 


*  (2760)     If  the  mass  m  were  collected  in  its  centre  of  gravity,  the  integral  ff  — - — 

dM  .  dM  [4767a] 

would  become    mf  -^  ;     and,  by  putting   f  —-^V    [4765],  it  changes  into   m.V,  as 

in  [4766].     The  expression  [4770]  is  found  in  a  similar  manner. 

t  (2T61)     If  we  suppose  m  to  be  spherical,  we  shall  have 

/•^dM.dm  „dM  .     ^ ,^„„  -, 

JJ  ^ —  =  "U-T'     as  in  [4 /67a]; 

and  if  ^f  also  be  spherical,  [4772o] 

.dM       M  ,  ^^dM.dm        m  M 


/ y  =  7  ;      hence,     ff—j^—  = 


Adding  to  this   the   parts   m.SV,  M.SV  [4768,4771],  depending  on  the  non-sphericity, 
we  obtain  the  complete  value  of 

ff — - —  =  — \-m.ôV-{-M.5V'.  [47721] 

■»«■  1  ■   1   •         1  ■    ,         M-\-m                ,      .       ,           ,          ,     M-\-m      ^^dM.  dm        .___,        ,  .  , 
Alultiplymg  this  by      — — ,     we  obtain  the  value  of     -jr. —  .JJ —    [4/72];  which 


372  THEORY  OF  THE  MOON  ;  [Méc.  Céî. 

Therefore,  in  the  preceding  expression  of    Q  [4756],  we  must  augment  the 

M-\-m 
term      — ■ — ,     by  the  quantity, 

[4773]  <^M+m).\~  4-~l=  increment  of  Q  [4756], 

J^n=/«-       in  order  to  notice  the  effect  of  the  non-sphericity  of  the  earth  and  moon. 

fron^t'be 

foEï  ^'     ^^  shall,  in  the  first  place,  suppose  both  bodies  to  be  spherical,  and 

"frîhMd     shall  develop  the  expression  of  Q  in  a  series.     Now,  we  have,* 


moon. 


[4774] 


[4775] 


1  1 


II    we   develop  the  second   member  of   this  expression,  according    to    the 
descending  powers  of  ?',  it  becomes, 

1        (xx'+yy'+z^^-lr^)  {xx'+yy'+zz'-lr^f 


+..^^y^.z^^^+^,. 


Taking  for  the  unit  of  mass  the  sum  M-{-m  of  the  masses  of  the  earth  and 
■'     moon,  we  shall  have,t 


j\t-\-7tl 

is  to  be  substituted  for     — ; —     in  the  function     Q    [47636,4756];    and  by  this  means  the 
general  value  of  Q  [4756]  will  be  increased  by  the  function  [4773]. 

*  (2762)     The  development    [4774,4775],  is  the  same  as  in  [4655?», c],  rejecting  the 
factor  — m',  which  is  common  to  all  the  terms.     We  may  remark,  that  if  we  use  the  values 
[4774a]    0Ï  R,    M-\-m     [4655,4775"],  the  expression  of     Q     [4756]  becomes      Q  =  ^  —  ^, 
which  will  be  of  use  hereafter. 

I  (2763)     If  we   put    I  for  the  latitude  of  the  moon,  we  shall  have,  as  in  [4759"], 
^''''"^     [31',34"']  Int., 

[4776t]  tang.Z=.;  sin./=^^^;  cos.Z=^^^^. 

If  we  proceed,  as  in  [4659,  Sic],  changing   r'  into  r,  and   U  into  v,  we  get, 
[4776c]  a;  =  r.cos.Z.cos.t);  y  =  r.cos. Z.sin.  ij;  s  =  7'.sin.Z=  ?-5.cos.?. 

[4776rfl     Now,  the  projection  of?-,  upon  the  plane  ot  xy,  is  represented  by  r.cos.Z  =  -  [4659a,4760]; 


VII.  i.  §2.] 


DEVELOPMENT  OF  Q. 


373 


1  =  M+  m  =  iJ-  ; 


r  = 


.r  ^ 


2/  = 


u 

COS.  D 

sin.f 


U  ^ 


y/I+Tg 


M 


u 


[4775"] 

[477C] 

Lunar  co- 
ordinates. 

[4777] 

[4778] 

[4779] 


We   shall   mark  toith  one  accent,  for  the  sun,   the   quantities  u,   s  and   v,     u^-g^r 
relative  to  the  earth.*     Then  we  have,t 


1  +  f. 


{«  »'.  COS.  (i)'—  v)-\-uu'.ss' —  hu'-.  (l-)-ss)|2 

(H-s'9)3.m4 


Q__  »  I  '»'•"'  /         ,     ^      |mM^C03.(«'— «)+««'.Ss'— àM'2.(l-|-ss)|3 


2.(1+s'2).m3 


Value  of 

[4780] 


substituting  in  this  the  value  of  cos.  I  [4776e],  we  get  [4776]  ;  moreover,  by  substitutino- 
the  value  of  r.cos. Z  [4776dl]  in  the  expressions  of  x,  y,  z  [4776c],  they  become  as  in 
[4777—4779]. 

*  (2764)     By  this  means  the  solar  co-ordinates  become, 
r'  the  radius  vector  of  the  sun  ; 

s'   the  tangent  of  the  sun's  latitude  above  the  fixed  plane  ; 
—  the  projection  of  the  sun's  radius  vector  upon  the  fixed  plane  ; 
v'  the  angle  formed  by  the  projection  of  ?•'  and  the  axis  of  x,  or  a;'  ; 


r 

\/i+«y 

m' 

COS.  v' 

x' 

«'    ' 

sin.  v' 

y 

=^ 

/          5 

t  (2765)     Substituting  the  value  of  R  [4656],  in  [4774a],  we  get, 
VOL.  III.  94 


[4777a] 
[47776] 
[4777c] 
[4777i] 

[4777e] 

Solar  co- 
ordinates. 

[4777/] 
[4777^:] 
[4777/i] 


374  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4781]  "^'^^  sun's  distance  from  the  earth  is  nearly  four  hundred  times  as  great  as 

that  of  the  moon  ;  so  that  îi'  is  very  small,  in  comparison  with  u  ;  and  we 

[4782]  may,  therefore,  neglect  terms  of  the  order  u'^,  in  the  lunar  theory.  We  may 
also  simplify  the  calculations,  by  taking  the  ecliptic  for  the  plane  of  projection. 
It  is  true,  that  this  last  plane  is  not  fixed  ;  but,  in  its  secular  motion,  it  carries 
the  moon^s  orbit  with  it  ;  so  that  the  mean  inclination  of  the  moon'' s  orbit, 
upon  the  variable  ecliptic,  remains  constant,  and  the  phenomena,  depending 
on  their  respective  inclinations,  are  always  the  same. 


[47S3] 


3.     To  prove  this,  we  shall  observe,  that,  from  5j  59,  book  ii.,  s'  is  equal  to 
[47841  .  i        '  '  1 

a  series  of  terms  of  the  form  A; .  sin.  {v'  -\-it  -\-  s)  ;    we  shall  represent  it  by* 


^        1     ,    m'       m'.r-  ,    „       ,  [xx'-\-yu'4-zz' — è  r2)2  (xx'-\-yif-\-zz' — i  r"2)3 

L  J  ^       )■         J-'        2/-3    '   -  c'o  '   -  r'^  ' 

Now,  if  we  substitute  the  values  [4776 — ^4779,4777e — A],  in  the  first  members  of  [47S0i,c], 
they  become,  by  shght  reductions  and  using  [24]  Int.,  the  same  as  in  the  second  members  of 
those  expressions, 

[4780i]  *^'+yy+~-^'= — -,  •  {cos.i!.cos.«'+sin.'y.sin.r'+«s'|  =  — 7.{cos.(r' — v)-\-ss'\; 

,       ,o       cos.{v'—v]-^ss'        A.(l+s2)         n  ii'.  cos.(  n'—  v)-\-%i  u'.s  s'—  I  uK(  \^ss) 
[4/80C]     xx^yyArZz'-lr-= — ■ ——  = :;^^^^ . 

By  means  of  these  values  the  expression  of  Q  [4780a]  becomes  as  in  [4780] .  For  the 
first  and  second  terms  of  [4780a]  correspond,  respectively,  to  the  first  and  second  of  [4780]  ; 
[4780rf]  jjjg  jj-ii,.^  Qf  [4780a]  gives  the  last  of  [4730]  ;  finally,  the  terms  of  [4780«],  connected  with 
the  factors  |  ot',  ^m',  by  the  substitution  of  [4780c],  become  respectively  equal  to  the 
terms  connected  with  the  factors  f ,  J,  in  [4780]. 

*,  (2766)     Using  the  same  notation  as  in  [4230],  we  shall  have,  for  the  earth's  latitude 

s",  above  the  fixed  ecliptic,  the  expression, 
[478g„]  ,"=r/.sin.."-iy'.C0S.^"      [1335']. 

Substituting  in  this  the  values  of    jj",    q"  [4334],  and  observing,  that 
[4785a']  sin.t)".cos.(,§-<  +  (3)— cos.j)".sin.(^<  +  |3)  =  sm.{v"—gt  —  p), 

we  get  the  earth's  latitude, 
[47856]  s"  =  ^.c.sm.{v"-gt-^). 

Changing  v"  into  the  sun's  longitude  v'  [4777f/],  we  get  the  sun's  latitude, 
[4765c]  s'  =  S.c.^m.{v'  —  gt  —  fi). 

This   is  of  the  same  form  as  [4785],  the  constant  quantities  c,    g,    p,  being  changed  into 
[4785c']     k,  — i,   —s,  respectively.     Hence,  the  coefficient  i  is  of  the  same  order  as  the  quantities 


VII.  i.  §3.]       INCLINATION  OF  THE  LUNAR  ORBIT  TO  THE  ECLIPTIC.  375 


s'  =  2  .  ^  .  sin..  (v'-\-  it  -}-  s)  ;  [4785] 

i  being  a  very  small  coefficient  [4785f?],  whose  product,  by    m'î«'^    we  shall 
neglect.     The    value  of   s,    neglecting  quantities  of  the   order    s^,   may  be     [4785'] 
represented  by* 

s  =  s,  +  2  .  A; .  sin.  (v  +  it  +  0  ;  [4786] 

s^  being  the  tangent  of  the  moon's  latitude,  above  the  apparent  ecliptic.    This 
being  premised,  we  have,t 


[4780'] 


g,  g",  he,  which  are  very  small  [4339,3113^].    The  values  [4339]  are  nearly  g=  —  36%     [4785d] 
g'= — 18*;    these  quantities  may  serve  to  give  an  idea  of  the  magnitude  of  g,   g',  Sic., 
though  they  are  not  computed  strictly  by  the  method  given  in  [1098,  &ic.]. 

*  (2767)     If  the  moon  were  to  move  in  the  apparent  ecliptic,  her  latitude  above  the  fixed 
plane,  or  its  tangent,  corresponding  to  the  longitude  v,  would  be  ^.k.s'm.[v-\-i(-\-s)  [4785].     M-gf  i 
Adding  to  this  the  quantity  s,  [4786'],  we  get,  very  nearly,  the  tangent  of  the  moon's  latitude 
s,  above  the  fixed  plane,  as  in  [4786]. 

t  (2768)  The  quantity  Q  occurs  in  the  first  member  of  [4787],  under  a  linear  form 
only  ;  therefore,  we  may  take  each  term  of  Q  [4780]  separately,  and  compute  its 
effect.  In  making  the  substitution  of  any  term  of  Q,  we  may  consider  the  quantity 
M.(l-|-««)^,  and  its  powers,  as  constant.  For,  if  we  put  (^=A.\u.(l-\-ss)~^'',  for  any 
terra  of  Q,  neglecting,  for  a  moment,  the  variable  parts  contained  in  Jl,  and  taking  the 
differential  of  log.  Q,  we  shall  get, 

(i  Q  J     du        ,       s  ds 

~Q    ~      'Tt~    '  l+ss  ' 
hence. 


T?)-o^ 


du  J  u  ^  ' 


ds 


l  +  ss        ^ 


[4787a] 
[47876] 

[4787c] 
[4787(f| 


Substituting  these  in  the  first  member  of  [4787],  we  find,  that  the  terms  mutually 
destroy  each  other.  Hence,  it  is  evident,  that  we  may  neglect  the  first  term  of  Q  [4780], 
which  corresponds   to     b^\,    A=l;    the  second  term,  which   corresponds  to    b  =  0, 


and  the  last  term,  which  corresponds  to     b= — 2,     A  =  - 


(!+*'«')»'     """-"-"- '  -I- ^-  -'      -—       2.[\-\-s's')û' 

Then  using,  for  brevity,  the  following  abridged  symbol  B,  we  get  from  [4780], 

\uit'.  COS.  (w — v')-\-uu'.s s'—hu'^.[\-\-ss)\ 


B  = 

dq 


(l  +  s's')i 
3  m'.  u' 

(i+s'TjJ' 


{l+s's').u^  ' 

\^B^  +  ^B^+hc.l; 

\B-\-^B^-^kc.].dB  +  hc. 


[4787e] 

[4787/] 
[4787g:] 
[4787/i] 


376  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[4787] 


[4788] 


„      ,       ,,  CcOS.ft! v') ")       Cs. COS. (v 1'') 

U^  À         ,     5«'  ,'      ■     o  i        i  ''*         •        /  /\  M 

f    -4--—  .cos.-(v — t)')  +  &c.  1    f -.sin.(i)  —  v  ) — s 

Substituting,  in   the  second  member  of  this   equation,  the  values   of  s',  s, 
[4785,4786],  we  get,* 


Substituting  the  partial  difterentials  of  Q,  in  the  first  member  of  [4787],  it  becomes, 

3m'. «'     ,„   ,       „^,    C</s     (dB\  fdB\        .     ,       ,    /rf-B\  > 

[4787V]  — — --.   B  +  iB^   .  \  -  .  (—)—"« -(-r  )  — (!  +  ««)•  (-7-)  \  • 

^  •■  (l+«s')}   '        '   -        ^    \dv     \dv)  \du)       ^    ^     '    \ds)') 

The  part  of  this  expression  depending  on  lŒ,  in  the  last  factor,  is  of  the  same  form  as  the 
first  member  of  [4787],  changing  Q  into  5;  therefore,  it  has  the  property  mentioned  in 
[4787i]  [4787 i]  ;  that  is  to  say,  we  may  consider  the  powers  of  m.(1 -{-««)""  as  constant.  Now, 
the  last  term  of  J9  [4787/]  corresponds  to  the  power  — 2  of  that  quantity  ;  therefore,  we 
may  neglect  its  partial  difterentials,  and,  in  finding  AB,  may  use  the  remaining  terms  as  in 
the  following  expression  ; 

[4787/fc]  B  =  7^x77,  •  1  ""'  "'•  COS.  {v  —  v')-\- M-'  m'.  s  s' I . 

The  partial  differentials  of  this  expression  give, 

ds     /'dB\  «'  C      ds     .     ,  ,.7 

[4787m]  -"^-O^dzS'T.»-  l^-cos.(i— i-O+^'-^^'l 


du  J        (\-\-s's').u' 


^.'l. 


[4787,v]  -(^+'')-(^)  = 


(i-j-^yj-M 


Adding  these  three  expressions  together,  we  find,  that  the  terms  depending  on  s-s'  destroy 
each  other,  and  we  get, 
ds     /dli\  fdB\        ,,    ,        .     /dB\  u'  (  ,  ds  ,.        ,-) 

Now,  if  we  retain,  explicitly,  the  terms  of  B  [4787/],  w  hich  do  not  contain  s,  s',  we  obtain, 

[4787;,]  B  +  fS^  =  '^'.  ^^cos.  {v  —  v')-~+^£.  cos.2(^  _  ^')  +  &ic.  ^ . 

Substituting  the  expressions  [4787o,p]  in  [4787A'],  and  neglecting  terms  of  the  third  order  in 
s,    s',  it  becomes  as  in  the  second  member  of  [4787]. 

*  (2769)     If  we  substitute  the  values  of  s',  s,  [4785,4786],  in  the  last  factor  of  [4787], 


VII.  i.  ^ 3]     EFFECT  OF  THE  SECULAR  MOTION  OF  THE  ECLIPTIC.  377 

*"'     Jcos.fî' — v') — 7: \-'—  .cos.^ft! — î)')  +  &ic. ;.<«,. COS. (î)  —  V) — '.sin.(i;  —  v')>.        [4789] 

ifi       I         ^  ^       2u    '   2u  ^  '   '  )   (  '  ^  '       dv  ^  ')) 

Hence  the  equation  [4755]  becomes,* 

elds    ,         ,              i.ml.u'^Si-\-hc. 
^^lv-^'+—^ Z^T^—  ;  [4790] 

or, 

dds 


'¥+^sO^  ' 


[4791'] 


0=1-2  +  5  +  ^-IT^  +  &C.  [4790'] 

If  we  neglect  the  excentricities  and  inclinations  of  the  orbits,  we  shall  have 

M  = -,      u'=—     [4826,4833];  a'  and  a  being  the  mean  distances  of  the     [4791] 

sun  and  moon  from  the  earth.  We  shall  see,  in  the  following  article  [4826], 
that  h-==  a,  very  nearly  ;  therefore,  we  shall  have  [4791  (/], 

we  shall  find,  that  the  terms  depending  on  k  mutually  destroy  each  other.  For  these  terms 
produce,  without  reduction,  the  following  expression,  neglecting  quantities  of  the  order 
mentioned  in  [4785']  ; 

2.t.|sln.(t)-|-i^-|-s).cos.(j; —  v')  — cos.(« -|-*'^  +  ^)  -s'"^-  ("  —  ^') — sin.  ('u'-|-i<-|-e)|. 
The  two  first  terms,  between  the  braces,  are  reduced  by  [22]  Int.  to 

sm.{{v-{-it-{-s)  —  (t)  —  v')l  =  sin.  [v'-\-it-\-s)  ; 

which  is  destroyed  by  the  third  term.  The  remaining  terms  of  [4785, 4786]  are  «'=0, 
s  z^  s,  ;     substituting  these  in  the  last  factor  of  [4787],  we  obtain  the  expression  [4789]. 


[4789o] 
[47896] 

[4789e] 


*  (2770)     Multiplying  together  the  two  factors  of  [4789],  we  find,  that  the  product  of 
the  term  cos.  («  —  v')    by   x,.cos.  (d  —  v'),  produces  Js, ,    disconnected  from  the  periodical    [4791a] 

angle    v  —  1;  ;  so  that  we  may  put  the  expression  under  the  form     -2 — '. JJl — ';     as  we    [47916] 

shall  soon  see,  that  it  is  not  necessary  for  the  present  object  to  mention  particularly  the  parts 
included  in  the  general  term  +  &c.  This  represents  the  value  of  the  function  in  the  first 
member  of  [4787],  and  if  we  divide  it  by  h^u-,  it  produces  the  three  last  terms  of  [4755]  ; 

which  will,  therefore,  be  represented  by     J-^Ll^^!/ +  ^- .       Substituting   this   in    [4755],     [4791c] 

and  dividing  by     1  +  75''/(t)--^'      we  get  [4790].      Reducing  the    denominator  of 
the    last  term  of  this    expression   into    a  series  ;    neglecting     m'^,     and    observing,   that 
idi)     l'^^^^^  'S  of  the  order    m'u'^,    it  becomes  as  in  [4790'].     Finally,  substituting   in    [4791rf] 
this  the  values  of  u,   u',  h^  [4791,  4791'],  we  get  [4792]. 
VOL.  III.  95 


378 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4799] 
[4793] 

Change 
ia  m. 

[4794] 


[4795] 
[4796] 

[4797] 
[4798] 


We  shall  put  mt  for  the  Burl's  mean  motion  ;  so  that  m  will  no  longer  denote 
the  moon's  mass;     we  shall  have,  by  ^  16  of  the   second  book, 


»r  = 


Then,  if  we   sui^pose  the  time    t    to  be  represented  by  the  moon's  mean 
motion,    which  can  always  be  done,  we  shall  have     -^  :=  1  ;  therefore, 

0  =  ^.  +  5  +  l.m^s,+  &c. 

Substituting,  in  this  equation,  the  value  of  s  [4786],  and  observing,  that  we 
may,  in  this  case,  change    it    into    iv,    we  shall  have,t 

0  =  — ;  +  (1+  f  .  m-)  .s^+2.k.{l  —  {i  +\yi.  sin.(«  +  i  î)  +  0  +  &c.; 

which  gives,  for  the  part  of  s,   relative  to  the  secular  motion  of  the  ecliptic, Î 


*  (2771)  If  we  change,  in  the  equation  [605' or  3700] ,  a  into  a',  and  n  into  m,  to 
[4794a]  conform  to  tlie  notation  [4791,  4793],  we  get  m^^=  tx.a'~^  ;  ij.  being  tlie  sum  of  tlie  masses 
of  the  sun  and  earth.  If  we  neglect  the  mass  of  the  earth,  in  comparison  with  that  of  the 
sun,  we  have  |A  =  )ft'  [4757"],  and  the  preceding  expression  becomes  as  in  [4794].  In 
the  moon's  motion  about  the  earth,  the  equation  [605']  becomes  n-=^{M-\-m).  a~^ 
[4757,4757'];  and,  as  the  moon's  mean  motion  nt,  is  here  represented  by  t  [4794],  we 
have  M=l  ;  substituting  tliis,  and  M-\-m  =  \  [4775"],  in  the  preceding  value  of  n^, 
we  obtain   1  =«"3  ^g  in  [4795].     Dividing  the  value  of  nv''  [4794]  by  this  last  expression, 


[4794c] 
[4794d] 


we  get   iir 


substituting  this  in  [4792],  it  becomes  as  in  [4796]. 


[4798a] 
[47986] 

[4798c] 


t  (2772)  The  terms  neglected,  by  writing  iv  for  it,  are  of  the  order  of  the 
excentricities  and  inclinations,  multiplied  by  the  very  small  quantity  i,  and  connected  with 
terms  containing  sin.  cv,  s'm.gv,  and  their  multiples,  as  is  evident  from  [4828,  4794c]. 
All  the  neglected  terms  are  considered  as  being  included  in  the  general  expression  +&ic. 
Now  we  have, 

(Ills 

s—s,-\--2.ksm.{v-\-iv-\-s)  [4786,4797];  hence  — 
substituting  these  in  [4796],  we  get  [4798]. 


:'^-2.t.(»+l)=.sin.(«+n.+£); 


J  (2*73)     This  equation  is   of  the   same   form  as  [865],  which  is    solved  in  [871]  ; 

changing  y,    fl^   t,  m  into  «, ,    l  +  |m^    v,    1  +  i,  respectively  ;    and  putting  for    a  Q,  or 

[4799a]     aK,  the  terms  under  the  sign  2   [4798].     These  changes  being  made  in  [871],  it  becomes 

as  in  [4799],  by  a  slight  reduction,  and  changing 


a;  the  signs  in  the  numerator  and  denominator. 


vil.  i.  §  3.]  DEVELOPMENT  OF  Q  AND  ITS  DIFFERENTIALS. 


379 


S.{'ii-\-P).k.s\n.{v-{-iv  +  i) 

This  last  quantity  is  insensible  ;  for  i  v,  at  the  most,  does  not  exceed  fifty 
centesimal  seconds  [  =  16',2]  in  a  year;*  and  ^nrv  expresses  very  nearly,  as 
we  shall  hereafter  see  [4800f/J,  the  retrograde  motion  of  the  nodes,  which 
exceeds  19'  [3373]  ;  therefore  fm^  is  at  least  four  thousand  times  as  great 
as  i  ;  so  that  we  may  neglect  the  term, 

^.k.\\—{i+\f].ûn.{v  +  iv-^î), 

in  the  differential  equation  [4798]  ;  and  then  this  equation  becomes 
independent  of  every  thing  connected  with  the  secular  motion  of  the  ecliptic. 
The  mean  inclination  of  the  moon's  orbit  to  the  apparent  ecliptic,  is  one  of 
the  arbitrary  quantities  of  the  integral  of  this  equation  ;  hence  we  perceive,  that 
on  account  of  the  rapidity  of  the  motion  of  the  moon'' s  nodes,  this  inclination 
is  constant;  and  the  latitude  s^  of  the  moon,  above  the  apparent  ecliptic,  is  the 
same  as  if  the  ecliptic  loere  immoveable.  We  may,  therefore,  suppose  s'  ^=  0, 
in  the  following  investigations  ;  which  will  simplify  the  calculations. 


[4799] 

[4800] 
[4801] 

[4802] 


Inclination 
(if  the  lu- 
nar orbit 
tu  the 
apparent 
ecliptic. 


[4803] 


[4804] 


Therefore,  we  have,  by  neglecting  quantities  of  the  order  m'  u'^  s\  m'  ?<'^,t      [4805] 


*  (2774)  This  agrees  nearly  with  the  remarks  made  in  [4785(/],  relative  to  the  value 
of  i.  Moreover,  tlie retrograde  motion  of  the  nodes  is  expressed  by  (g — 1)  .v  [4817],  and 
the  values  of  m,  g  [5117],  give  g — l^^m^  nearly  ;  therefore,  the  retrograde  motion  of 
t!ie  nodes  is  nearly  equal  to  ^m^.v,  as  in  [4800].  The  same  result  may  be  obtained 
analytically;  for,  if  we  neglect  terms  of  the  order  p"^,  e'^,  the  motion  of  the  nodes  [5059] 
becomes   \p".v.     Now,  by  comparing  the  coefficients  of  sin.(^D  —  <)),  in  [5053,  5049],  and 


retaining  only  the  first  term  of  each  of  them,  we  get, 


V 


$  m 


[5094]  ; 


[4800a] 
[48005] 


[4800c] 
[4800rf] 

[4800c] 


whence,  the  motion  of  the  nodes  becomes  iii".v  =  ^nfi.v.  This  exceeds  19''  in  a  year 
[3373]  ;  which  is  more  than  4000  times  the  value  of  iv,  assumed  in  [4785rf]  ;  hence  the 
term  of  s,  [4799]  must  be  insensible,  and  we  may,  therefore,  neglect  the  corresponding  terms 
of  [4798],  which  are  given  in  [4802].  Then  all  the  remaining  terms  of  [4798],  which 
are  included  in  the  expression  -|-&c.  [47986],  maybe  considered  as  independent  of  the 
secular  terms  arising  from  i. 

t  (2775)     Substituting   s'^0    [4304]  in  the  value  of    Q    [47S0],  it  becomes,  without 
any  reduction,  as  in  [4806a].      Developing  the  powers,  and  neglecting  terms  of  the  orders     [4800/] 
mentioned  in  [4805],  it  becomes  as  in    [48066].     This  is  reduced  to  the  form  [4806c]  by 


380  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[4806] 


+  !!LL!i_.^3.(l— 4s^).cos.(îJ— 'd')  +  5.cos.(3î;— 3t0|. 


[4807]      Hence  we  get,  by  neglecting  quantities  of  the  order  m'u'^s^,* 

\duj  ^  u   \clsj         (1+s')^  2m3      '      '  ^  ^* 

[4808] 

_  ^'^'* . I (3 _ 4s"-)  . COS. (v—v')  +  5 . COS.  (3 ^— 3i;') | ; 


using  [6, 7]  Int.  ;  and  if  we  connect  the  terms  depending  on  the  same  powers  of  ?t'   it 
becomes  as  in  [4806J  ; 

Cl+^^-[uu'.cos.{v—v')  —  iu'^.{l+ss)f 
[4806a]     q= - \-m'u'.{  "  n_L    ws 

[48065]         =^  +  mV.  j  ,3  _^,, 

3,,'2  3ji'3 

0+^2-[i+àcos.2(î,-^')]-^-(l+")-cos.(.-î)'), 


« 


[4806c]         =-—^  +  rm, 

+  ^.Ucos.  (,,-,;') +icos.3(i;-i;')]--—7,— 

*  (2776)     The  partial  differentials  of  Q  [4806],  taken  relatively  to  v,   s,  u,   become, 
without  any  reduction,  as  in  [4809,4810,4810a],  respectively.      Multiplying  [4810]  by 

-,  we  get  [48106]  ;    adding  together  the  expressions  [4810a,  Zi],  and  making  some  slight 
u 

reductions,  we  get  [4808]  ; 

1  m'  m'3 

[4810a]  V(i«y  ~    \       3  m' «'1 

^      ^  ■*         ^-.[(3— 12s2).cos.(t)  — t)')  +  5cos.(3^  — 3u')]' 

s    /dQ\                   ss            m'.u'^s^        3  m'.  «"Isa  .  ,, 

[48105]  û-UJ=-fî+^)î ^ ^^.cos.(.-.) 


[du)  i 


VII.  i.  §4.J  APPROXIMATE  VALUES  OF  s,  u,  t.  381 

I  -^]  =z -— .sin.C2t>  — 2i)) 

\(lv  J  2»-  ^  •^ 


[4809] 


—  '!l^^-.l3.(l—As-).sm.(v—v')-^l5.sm.(3v—3v')\ 


(1Q\  us  m'.u'^s       3m'. u"^  s  ,  ,,  r^oim 


4.  7*0  integrate  the  equations  [4753 — 4755],  we  shall  observe,  that,  by 
excluding  the  sun's  disturbing  force,  the  moon  will  describe  an  ellipsis,  in 
which  the  earth  occupies  one  of  the  foci.  We  shall  then  have,  as  in  [532,533], 


[4810'] 


S  =  /.sin.('y  — 0;  [4811] 

u^j^,j^y\n  +  ssy+e.co..iv-.)\.  ;^4812] 

5,  11,  in  an 
iiiv  iriahle 
eliipsia. 


In  these  equations,  y  is  the  tangent  of  the  inclination  of  the  lunar  orbit  ; 
d  the  longitude  of  its  ascending  node  [533"]  ;  e  and  w  are  tivo  arbitrary 
quantities,   depending  chief  y ,  on   the   excentricity  of  the   orbit,  and  on   the  ^ 

position  of  the  perihelion  [534'].  y  and  e  are  very  small  quantities.  If  we 
neglect  the  fourth  power  of  7,  we  shall  have,* 


[4813] 


[4815] 


U  = 


/,3.(l  +  y3)-n  +  l>'  +  e.cos.(p— ^)  — iy^cos.(2t;-20|.  [4816] 

In  this  value  of  u  the  ellipse  is  supposed  to  be  immoveable  ;  but  we  shall 
soon  see,  that  in  consequence  of  the  sun'' s  action,  the  nodes  and  perigee  of  this 
ellipsis  are  in  motion.     Then  putting, 

(1  —  c).v  =  the  direct  motion  of  the  perigee  ; 

{g — \).v  =  the  retrograde  motion  of  the  nodes  ;  ['iS,\é] 


*  (2777)     Developing    (l  +  s.s)i,    according  to  the   powers  of  s,    substituting  [4811], 
neglecting  s^,  and  reducing,  by  means  of  [1,3]  Int.,  we  get,  successively, 

(l+,s)i  =  l+J,a_,,4 

=  l  +  |4i  — 2Cos.(2y— 20)^  — Ç.^f  — |.cos.(2«  — 20)+|cos.(4j;— 4â)f 
=  (1  +  ^7"— sV/)  — (ir'— tf/)-cos.(2«  — 20)  — ^ij^4.cos.(4t,— 4ô). 

Substituting  this  in  [4812],  and  neglecting  y'^,   it  becomes  as  in  [4816].     We  have  retained 

the  terms  of  the  order  7^.   in  [4812a],  because  they  are  required  hereafter.  '■  ^ 

VOL.  III.  96 


[4812a] 


382 


THEORY  OF  THE  MOON  : 


[Méc.  Cél. 


we  shall  have,  from  [4811,4816],* 

[4818]  s  =  '/.sin.(gv—è); 

1 


[4819]  u^—j---^.{l  +  l7'+e.cos.(cv  —  ^)  —  {';~.cos.(2gv—2^)\. 

Assumed  ^       \    I     J 

forma  of 

movcabiJ"  If  we  substitute  this  value  of  «,  in  the  expression  of  dt  [47531,  observing, 

ellipsis.  L  J  o 

[4820]  x}asX,  if  we  neglect  the  solar  attraction,    \f]     vanishes  ;  we  shall  have, 

(  l  +  l.fe'^+j.^)— 2e.(]+|e^+f7")-cos.(c«— ^) 

[4821]  dt  =  h^.  dv .  )    +|.e'.cos.(2cv— 2?^)— e^cos.(3ci)— 3n)+i7^cos.(2^i'— 2i')   \. 


—^.e7^.{cos.{2gv+cv — 2t) — i^)+cos.(2^î;— ct' — 2d+j:)  \ 


/ 


[4891a] 

[48216] 

[4821c] 
[482W] 
[4821e] 


[4821/]     c'd  — 


[4821gr] 


[4891A.] 
[4821i] 
[48914] 
[4821?] 

[4821m] 


*  (277S)  The  object  of  this  article  is  to  obtain  approximate  vakies  of  m,  w',  s,  v', 
expressed  in  terms  of  v  ;  for  the  purpose  of  substituting  them  in  Q,  and  in  its  differentials  ; 
as  is  observed  in  [4838'].  Now,  s,  ii  [4818,4819],  are  the  approximate  values  of  s,  v, 
corresponding  to  the  equations  [4755,4754],  noticing  two  of  the  most  important  perturbations, 
namely  ;  the  mean  motions  of  the  perigee  and  nodes.  Substituting  these  in  [4753],  we 
get  tlie  approximate  values  of  dt,  t  [4821, 4822],  which  are  afterwards  corrected  in 
[5081,5095].     In    finding  the  approximate   value  of   dt    [4821],  from  [4753],  tlie  term 

glected,  and  then  [4753]  becomes     dt  =  -—;^;     in  which  we  must  substitute  the 

value  of    u   [4819].     In   making  these  substitutions,  we  shall  put  for  a  moment,  for  brevity, 

f —  1  y2 A^^.  cos.  (2^  «  —  2d)  ;  and,  during  the  process  of  the  calculation,  we  shall  omit  the 

symbols    ê,    w,    ra',    ivhich  are  connected  respectively  with  the  angles    gv  —  è,    cv  —  ra, 
^'^     c' mv  —  zi';    taking  care  to  re-substitute  them  at  the  end  of  the  o2}eration.     This 
abridged  form  of  writing  the  angles,  will  be  used  frequentlij,  in  the  notes  which  follow  ;   it 
saves  considerable  labor,  renders  the  formulas  more  simple,  and  cannot  be  attended  with  any 
inconvenience.     Hence,  the  preceding  expres.?ion  of  tZ^  [4821rf]  becomes  as  in    [4821A]; 
developing  the  factors,  and  neglecting  Z^,  fe^,    eS   7^  he,  we  get  successively  [4821  i,fc,Z]. 
Substituting  the  value  of  /   [4821e],   and  reducing,  by  means  of  [6,7,20]  Int.,  we  get 
[4821w]:  connecting  together  the  terms  depending  on  the  same  angles,  we  obtain  [4821]; 
whose  integral  is  as  in  [4822]  : 
dt=P.{l+7'')-.dv  .\l  +  {f+e  .cos.cv)]-^ 
^p(^lJ^2y^}.dv.\l—'2{f+e.cos.cv)-j-3(f+e.cos.cvf—'i(/+e.cos.cv)^ 
^p(^lj^2y^}.dv.\l — 2e.cos.C!)  +  3e2.cos.^c«— 4e^.cos.3ct) — 2/+6/e.cos.c?)} 
=P.dv.{{l-^2y^)  —  2e{l  +  2f).cos.cv-{-2e~.cos.^cv — Ae^.cos.hv— 2 f-\-6fe. cos.  cv\ 
(l_|-Oya)_2fi(l-f27^)  .cos.ciJ  +  ae^.  (1  +  C0S.2CI')— e^(3cos.c!;+cos.3ci))^ 
=li^-^'i'-^_i^^,^j^^^2_f,f^^^2gv+iey^.cos.cv—^ef.[cos.{2gv4-cv)+cos.{2gv-cv)]<^' 


VII.  i.  §  4]  APPROXIMATE  VALUES  OF  s,  u,  t.  383 

This  gives,  by  integration, 

/=constant+/i^f.(I+|e^+|r)— — .(l+|e=+|r).sin.(CT— ^) 

.sin.(2c!; — 2^) -— .sin.(3cj; — 3sî)+— ^.sin.(2^tj — 2^)  [4822] 


4c  3c  ^  ^S 

—  r7T-f-l-sin-(%»'+<^«— 2^— '')— T7^--N-sin.(2ffî}— «;— 20+ra)  ; 
4. (-2^+0)         ^  ^  '^•(2^ — 0 

the  coefficients  of  this  equation  are  modified  a  little  by  the  sun's  action,  as 
we  shall  hereafter  see  [5081,  5095]. 

In  the  elliptical  hypothesis,  the  coefficient  of  v,  in  this  expression,  is,  by      Mgoo'i 

3, 

[541' — 543],  equal  to   a^  ;    which  gives,* 

/t3.(l  +  |e^+|^2)=a^;  [4823] 

«  being  the  semi-major  axis  of  the  ellipsis  ;  hence  we  have,  [4824] 

h  =  a^,(l  —  ie"'-hy);  [4825] 

consequently, 

u  =  --^.{l  +  e-+lf-\-e.(l  +  ec).cos.(cv—^)  —  ly-.cos.(2gv—2ê)}.  [4826] 

_3_ 

Then,  by  putting     n=  a  ^     [482Sa],  we  get,t  [4827] 


*  (2779)     Substituting   (x=rl    [4775"],  in  [541'J,  we  get    n=  a  ^;  hence  [543]  gives 
«-f-a^e=«-y  +  &c.  ;    in  which  the  coefficient  of  îj  is   a-".     To  make  this  conform  to  the  '  "'' 

result  of  the  elliptical  theory  [4822],  we  must  put  the  coefficients  of  v  equal  to  each  other; 
hence   we  get   [4823].     Dividing  this  equation  by  the    coefficient  of  h^,  and  taking  the     [48236] 
cube  root,  we  obtain   h  [4825],  neglecting  terms  of  the  fourth  order  in    e,  j.     This  value 
of   A  gives     A=.(l  +  y^)  =  a.(l-eS);     whence,     ^^-_  ==:l.(i+e^)  ;      substituting     ^4823^] 
this  in  [4819],  we  get  [4826]. 

t  (2780)     Multiplying  [4823]  by    1— 1-/,  and  neglecting  /,  we  get 
substituting  this  in  the  third  term  of  the  second  member  of  [4822]  ;  also  [4823],  in  the 

3 

second  term,  and  putting  the  constant  quantity  equal  to    — oF^c-,    we  shall  obtain  for  these 


384  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4828]      nt  +  s=^  v  —  ~.(l—^f).sm.(cv—z,)+'^-^.sin.{2cv—2^) 


Ac 

2 


mate  .^     .Sill,  (o  CV O 'CJ  )  H  .  oui.  \  ^ii  u -i-o  i 

value  of  3C  '^  4^  ^     ^  ^ 

nt-\-s. 

Q         2  O         2 

~  77iï^T~^  •  sin- (25- î' +  c  tJ — 2  d — ^)  —  — -""-^^^ .  sin.  (2  £•  15 — c  I' — 2 1' +  ta  )  :• 
4.(25-4-0)  vol  ^       4.(2^— c)  ^    °  '     ^' 

£    being  an  arbitrarj  constant  quantity.      In  substituting   nt-\-e,    we  may 

r482Ql 

suppose  c  and  g  to  he  equal  to  unity  [5117],  and  neglect  quantities  of  the 
order  e^,  or  ey^,  in  the  coefficients  of  the  sines.  Thus  we  shall  have,  by 
retaining  the  term  depending  on  sin.(2^t' — cv — 2i-\-vi),  which  will  be 
useful  hereafter  [4828f/]  ; 

[4830]  ^*^  +  ^  =  «  — 2e.sin.(ctJ  —  a)-f-ie^sin.(2c?;— 2^)  -\- \y^.sm.{2gv — 2è) 

— fey^  sin.(2^w — cv — 2<)  +  ^). 
[4831]      If  Yve  mark  Avith  one  accent  for  the  sun,  the  symbols  relative  to  the  moon 

Approxi-  •^ 

riucsof      [4779'],  and  observe,  that   /=  0    [4804],  we  shall  have,* 

t,    u'. 

[4832]  n't  +  s'  =  v'—2e'.sm.  (c'v'—^Z)  +  2  e'^.siu.  (2c'v'— 2^')  ; 

u'=  -,.  n  +  e'^+e'.n  +  e'^).cos.(c'v'—z,')\. 

[4833]  a'     '      '  '        \     '        ->  V  /5 

[4834]      The  origin  of  the  time  t   being  arbitrary,  we  may  suppose  ;  and  s   nothing, 


3          3          2e    a 
[48286]     three  terms,  the  expression      —  a-  e-\-a-  v .«^.(1 — j}^).sin.(fi.'— to).  Substituting  this  in 

[4822],  then  multiplying  the  first  member  by  n,  and  the  second  by  its  equivalent  expression 

a  ^    [4823a],  it  becomes,  by  slight  reductions,  as  in  [4828]  ;  observing,  that,  in   the  second 

_3 

[4828c]  ^n*^!  'h'^*^  ''"^^  °f  [4822],  we  may  put  h^a  -  ^  1  [4823],  since  these  terms  are  of 
the  second  or  third  orders  in  e,  j.  Now,  putting  c  and  g  equal  to  unity,  in  the  coefficients 
of  [4828],  and  retaining  terms  of  the  second  order  in   e,    /,  also  the  term  depending  on  the 

r4828(/l  angle  2^t)  —  cw,  we  get  [4830].  The  reason  for  retaining  this  term,  is  on  account  of  the 
smallness  of  the  divisors  introduced  by  it,  in  consequence  of  2°- — c  being  very  nearly  equal 
to  unity.     For  the  values  of  c,   g,    m  [5117],  give  very  nearly, 

[4828e]  c=l— #w^         ^=l+f'K^  2^— c=l+3m-. 

*  (-2781)     The   values  [4832,4833],  relative  to  the  sun,  are  deduced  from  those  of  the 
[4832»]     moon  [4830,4826],  by  merely  accenting  the  symbols,  as  in  [4779'];  observing   also,  that 
s'=0  [4804],  corresponds  to  y'=^  [4818]. 


vu.  i.  §4  ]  INVESTIGATION  OF  v',  u',  IN  TERMS  OF  v.  386 


If 


and  then  putting    -  =  m,    the  comparison  of  the  values  of  nt  and    n't  will      [18351 
give,* 


n 
* 


v'  —  2e'.  sin.(c'i''—  ^')  +  f  e'^  sin.2(c'îj'—  ^') 
=  in  V  —  2m  e  .  sin.  (c  v  —  ^)  +  t  »«  e-.  sin.  ('2  c»  —  2  ra) 

^  ^         ■*  ^  ^  [4836] 

+  {  m.y.  sin.  (2gv  —  2  o)  — ;^  mey~.  sin.(2o-r  —  cv  —  2  â  +  w). 
Hence  we  deduce,  by  observing,  that   c'   varies  but  very  little  from  unity,t  [4836'] 


*  (278-2)     If  we  take,  for  the  origin  of  i,  the  moment  when  the  bodies  are  in  their  mean 
conjunction,  or     ni-\-s    equal  to   n't-\-i',   we  sliall  have    s^e'=0.     Substituting  these  in     [4834a] 
[4830,483:2],  we  get  the  values  of  7it,    n't.     Multiplying  the  former  by  m,  and  substituting 
mn  =  n'   [4835],  we  get  an  expression  of  n'l,   wiiich  is  to  be  put  equal  to  that  in  [4832]  ;     [48345] 
hence  we  get  [4836]. 

t  (2783)     We  may  obtain    v'   from   [4836],  by  means  of  the  theorem  of  La  Grange 
[629c],  which,  by  changing  ■\'X  into  x,  then  x  into  v   and  t  into  t,  becomes, 

v'—F{v')  =  t;  ^4837„^ 

,_,,,,,    d.Fiif  ,        d2.F(t)3      „ 
i,'=t+F(t)  +  è.^  +  i.-Ai+&c.  [48376] 

Comparing  the  equations  [4836,48.37a],  we  find,  that  t    represents  the  second  member  of 
the  equation  [4836],  and,  tliat 

F{v')  ==  Se'.sin.  {c' v'—-:)  —  ^é^.sm.{2c'v'—2i^').  ^483^, 

Changing  v'  into  t,  we  get  F{t)  [4837e],  its  powers  [4837/],  and  the  differentials  [4837^], 
omitting,  for  brevity,  the  symbol   — tt/,    which  is  connected  with   c't  ;    the  reductions  being 
made  by  means  of  [1,2,  17]  Int.     Substituting  these  in  the  second  member  of  [48376],  we     L^SJ/^/] 
get   v'    [4S37A]  ; 

F(t)  =  2fc'.sin.(c't  — ^')  — ^e'-.  sin.(2c't  — 2ûj')  +  &ic.;  [4837,] 

F{xf=2<:'K  (l-cos.2c't)  — |e'3.  cos.c't+&:c.  ;  F{lf=6e'\  sin.c't  +  &c.  ;     [4837^] 

è--^=2É'-2.sin.2c't  +  fe'='.sin.c't  +  &c.;  è- -5^  =— e'^.  sin-c^t+Sic.  ;     [4937^] 

„'  =  t  +  (2e'-^  «'=*). sin.(c't-t.')+|e'2.sin.(2c't- 2^')-  [48.37;^] 

Now,  t  represents  the  second  member  of  [4836],  and  the  substitution  of  this  value  in  the 
first  term  of  [4837A]  produces  the  four  first  terms,  or  the  two  first  lines  of  the  second  [4837i] 
member  of  [48-37].  The  last  term  of  [4S37AJ  produces  the  last  term  of  [4837],  by  putting 
for  t  the  first  term  mu  of  the  second  member  of  [4836]  ;  it  being  unnecessary  to  take  any 
other  term  of  t,  because  m  is  of  the  same  order  as  e,  or  e'.  To  obtain  the  value  of  the  [403711 
second  term  of  v'  [483TÂ],  we  must  have  the  expression  of  sin.  (c't — -a').  Now,  as  this 
VOL.  III.  97 


386  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[4837] 


v'^m  V  —  2me  .  sin.  (c  v  —  in)  +  i  m  e".  sin.  Ç2.C  v  —  2  ra) 

+  i  m  7 -.  sin.  (2gv  —  2è)  —  ^  m  e  f.  sin.  (2gv  —  c  v  —  2  è -{- -.->) 


Approxi- 

TilTesof  +  2e'.  (1— ie'^)  .sin.  (c'mv—  ^')  —  2mee'.  sin.  (c?;  +  c'mv  —  ra  — xa') 


r  ,    M  . 


—  2  m  e  e'.  sin.  (cv  —  c'mv  —  ^  +  ^')  +  f  ^'^'  ^i"*  (^  c'  w  î'  —  2  -/) 

,       1      C  l  +  e'.(l— ie'2).cos.(c'?»i'— w')  +  «'^-cos.(2c'mî;  — 2ra')  )* 

«' '  (     -t~''''fi6'.cos.(c« — c'mv — zs-^-z}') — me  e'. COS.  {cv-{- c'mv — s — u')  )  ' 

5.     We  must  substitute  these  values  of  u,    u',    s  and  v',  in  the  expression 

[4838']     of    Q    [4806],  and  of  its  partial  differentials  [4808—4810],  which  will,  by 

this  means,  be  developed  in  sines  and  cosines  of  angles  proportional  to  v  ;  but 

it  is  necessary,  for  this  development,  to  establish  some  principles  relative  to 


term  is  of  the  order  e',  it  will  be  sufficient  to  take  the  two  first  terms  of  [4836],  namely  ; 
[4837i]  tz=mv — 2me.sm.{cv  —  a);  whence,  f't  —  ■ûi'=:(^c'mv  —  ra') — 2c'me.sm.{cv  —  «). 

Developing  the  sine  of  this  expression,  by  means  of  [60,  18]  Int.,  neglecting   e-,  we   get, 

successively, 

[4837m]    sin,  (c' t  —  ra')  ==  sin.  (c'm  v  —  to')  — 2c'  m  e  .  sin.  {c  v  —  zs)  .  cos.  {c'mv  —  ra') 

[4837n]  :=sin.(<''mf — ~/) — c'ine  .sm.{cv-\-c'mv — ra — a')  —  f'me  .sln.(f  v  —  c'mv  —  ■a-\-z!'). 

Multiplying  this  by  its  coefficient     2  e'  —  i  e'^,    or    2  e'.  (1 —  ^  e'^),  neglecting  terms  of  the 
fourth  order,  and  putting    c'=  1,    we  get  the  sixth,  seventh  and  eighth  terms  of  [4837]. 

*  (2784)  To  obtain  u,  we  must  substitute  the  value  of  v'  [4837]  in  [4833]  ;  and, 
as  we  retain  terms  of  the  third  order  in  e,  c',  /,  m,  in  [4838],  it  is  necessary  to  retain 
those  of  the  second  order  in  v'  [4837].     Hence,  if  we  put  for  a  moment,  for  brevity, 

[4838a]  ~  =  2  c'.  sin.  {c'  mv  — ra')  -|-  J  e'^.  sin.(2c'?rt  v  —  2  to')  —  2m  e  .  sin.  {cv  —  to)  ; 

and  observe,  that  c'  is  very  nearly  equal  to  unity,  we  shall  have,  from  [4837], 
[48386]  v'=7nv+z,     and     c' v'—zi'—{c' mv  —  to')  +  s. 

Its  cosine,  reduced  by  formulas  [23,4.3,44]  Int.,  becomes,  by  neglecting  z^, 
[4838c]  cos.  (c' v' —  w')  =  cos.  z  .  cos.  (c' mv  —  to')  —  sin.  z  .  sin.  {c' m v  —  to') 

[4S38(i]  =  (1  ~  2  ~^)  •  cos.  {cm  v  —  to')  —  z.  sin.  {dmv  —  to')  ; 

hence, 

e.  (l  +  e'2).cos.  (c'jj  — to') 
[4838e]  =e'.  (1  +  ê'-)  .cos.  (c'  mv  —  to')  — |  e'  z^.  cos.  (c'mv  —  to')  —  e'  z .  sin.  {c'mv  —  to'). 

Now,  substituting  the  value  of  z  [4838a],  in  the  first  members  of  [4838^,  A],  neglecting 


VII. i.  §5.]    REMARKS  ON  THE  DIFFERENT  ORDERS  OF  THE  TERMS.  387 

the  magnitudes  of  the  quantities  which  enter  into  these  functions,  and  on  the      [4839] 
influence  of  the  successive  integrations  upon  the  different  terms. 

The  value  of  m    [o\\l\  is  very  nearhj  equal  to  the  fraction  ^\  \    loe  shall      [4840] 

consider  it  as  a  very  small  quantity  of  the  first  order.     The  excentricities  of  o,do,.  or 

the  orbits  of  the  sun  and  moon,  and  the  inclination  of  the  lunar  orbit  to  the 

ecliptic,  are  nearly  of  the  same  degree  of  smallness  [5117,  5194].     Thus,  %oe        g^^ 

shall  regard  the   squares  and  products   of  these   quantities,  as  very  small 

quantities  of  the  second  order  ;  their  cubes  and  products  of  three  dimensions, 

as  very  small  qua7ititics  of  the  third  order;  and  so  on  for  others.     The  sun's 

m'  «'•* 
disturbing  force  is  of  the  order*    -A5-,     and  we  have  seen,  in  ^  3,   that  this      [4842] 

quantity  is  of  the  order  m",  or  of  the  second  order.     The  fraction    -,  being 

very  nearly  equal  to    ^i^,    may  be  considered  as  of  the  second  order.      We     [4843] 
shall  carry  on  the  approximation  to  quantities  of  the  third  order  inclusively  ; 

terms  of  the  fourth  order,  also  those  depending  on    the  angle    Sdrnv  —  3  ro',     we   get, 
successively,  by  using  [31, 17,2]  Int.,  the  following  expressions;   omitting,  for  brevity,  the     [4838/] 
symbols  -n,    n',  as  in  [4821/]  ;  y 

—  y'z^.  COS.  (c'  mv  —  •n')  z=  —  e' '.  (2  sin.  d  mv  .  cos.  c  m  v)  .  s'm.  d  m  v 

=  — e'^.  sin.  2  c'  m  V  .  sm.  c'  m  V  :=^  —  i  e'  ^.  cos.  d  mv: 


[4838g-] 


—  e'z.sin.  {d  mv  —  z/)  =  —  e'^.  (1 — cos.  2  c' m  «)  —  |e'^.  cos.  cm  « 

-\-me  e'.cos.  [cv  —  d  inv)  —  mee'.  cos.  (cv  -\-  dmv). 

Substituting  [4838^,  h'\  in  [4833e],  we  get,  by  connecting  the  terms, 

e'.  (1+  c'2)  . cos.  (c  »  —  w')  =  —  c'^+  e'.  (1—  i  e'^)  .  cos.  d  mv  -\-  e'"-.  cos.  2  d  m v 

-\-mcd.  cos.  {cv —  dmv)  — mc  e'.cos.  (cv  +  dmv). 
Finally,  by  the  substitution  of  this,  in  [4833],  we  get  [4838]. 


[4838/i] 


[4838i] 


*  (2785)     The  accelerative  forces  [4763rf'J,  are  represented  by  the  partial  differentials  of 
Q,  relative  to  the  co-ordinates.     Thefe  partial  difltrentials  occur  in  the  general  equations 
[4753 — 4755],  and  are  computed  in  [4807— 4810J.      Now,  if  we  compare  the  part   of    ^^  '*  "^ 
[4808  or  4810],  which  does  not  contain  the  disturbing  mass    m',   with  the  chief  term  of  the 
same  equation,  depending  on  this  disturbing  mass,  we  shall  find,  that  it  is  of  the  order 

^4-'     °^     '^     [4791];  which,  by  means  of  [4794,  4795],  is  of  the  order  m^.  l'*S'*26] 


388  THEORY  OF  THE  MOON  ;  [Méc.  Ctl. 

and  in  the  calculation  of  these  inequalities,  toe  shall  take  notice  of  quantities 
[4844]      of  the  fourth  order;*    but  we   must  take  particular  care    not  to  omit  any 
quantities  of  that  order  in  the  integrals. 

The  equation  [4754]  becomes,  by  development,  of  the  following  form,t 

„         (Ida    ,    -.-TT 
[4845]  0  =  — ^+iV-.  M  +  n  ; 

[4845']     N^  differs  from  unity  but  by  a  quantity  of  the  order  «r  [4845c],  and  n  is  a 
series   of  cosines,    of  the   form    /t.cos. (/ y  +  ;)    [4961].      The   part   of  «, 

[4o4o] 

relative  to  this  cosine,  is  represented,  as  in  [870',  871],  by 
[4847]  „__A_.cos.  (it'  +  O- 

Now,  it  is  evident,  that  if  r  differs  from  unity  by  a  quantity  of  the  order  m, 
[4848]      j^j^g   jgj.,^  k.cos.Çiv  -{-  ô)    acquires,   by  integration,  a  divisor  of  that  order; 

which  increases  the  term  considerably  ;  so  that  it  will  become  of  the  order 
^  ^  r — 1,  if  it  be  of  the  order  r,  in  the  differential  equation.  We  shall  see 
[4850]      hereafter,  that  the  greatness  of  the  inequality  named  the  evection,  arises  from 

this  cause. t 


*  (2786)     The  angles  connected  with  coeflicients,  as  far  as  the  third  order  inclusively, 
[4844a]     are  retained  ;  and,  in  computing  the  coefficients  of  these  terras,  the  approximation  is  carried 
on,  so  as  to  include  terms  of  the  fourth  order. 

t  (2787)     The  chief  inequality  of  M  [4819],  is  that  depending  on    cos.  (ci;  —  ra),  which 
we  shall  represent  by    e.cos.  (cd  —  ra)  ;    putting  the    other  terms  equal  to    Su,     so  that 

iAaA^„-\  .  dilu  „  ,  d-.  (]u 

iwioai      „^e_cos_(-c!)  — w)  +  <Sit.      Its  difierential   gives      —  =  — c^  e.  cos.  (cv  —  îi)  + -^    . 

Multiplying  the  first  equation  by  c^  and  adding  the  product  to  the  second  equation,  we  get, 

(Wu    ,     „  d'^.Au         , 

U  c~  u= \-  c~.  au. 

[48455]  dfi  ^  dr2    ~ 

Putting  the  second  member  of  this  last  equation  equal  to   — n,   we  get, 

''''"       12  IT. 

\-  c"  u  =  —  IT 

[4845c]  dl^     ' 

and  this  is  of  the  same  form  as  [4845]  ;    N^  being  changed  into  c-,  which  differs  fiom  unity 

by  a  quantity  of  the  order    3  m-  [4828e]. 

X  (2788)     The  evection  depends  on  the  angle     2v  —  2mv—cv-\--m,    and  its  cosine  is 
multiplied    by    ./3/"e,   in   the  expression  of  <5k  [4904].     Now,  in  finding  ^/i>,    from  the 
[4850a]     equation  [4999],  we  must  divide  by  the  factor    1  — (2  — 2/«  — c)^    which  is  of  the  order 
m  ;  and  by  this  division  its  value  is  very  much  increased. 


VII.  i.  §  5.]  REMARKS  ON  THE  DIFFERENT  ORDERS  OF  THE  TERMS.  389 

The  terms   where   i    is  very  small,  and  which  depend  only  on  the  sun's     [4850'] 
motion,  do    not    increase,  by  integration,    in  the   value  of  u  ;*    but,  it  is 
evident,  from  the  equation  [4753],  that  these  terms  acquire,  by  integration,     [4850"] 
the   divisor    /,    in  the   expression   of    t  ;t    we   must,  therefore,   pay  great 
attention  to  these  terms.     It  is  on  them,  that  the  magnitude  of  the  annual      [1851] 
equation  depends. 

The  terms  of  the  form    k .dv.sm(iv-{-!),    in  the  expression  of  (~^)-~Tj      [4852] 

[4753, 4754]  acquire,  by  the  integration  of  that  differential  expression,  a  divisor 

of  the  order  i,  in  the  value  of  u.  Hence,  it  would  seem,  that  in  the  expression 

of  the  time  t,  these  terms  ought  to  acquire  a  divisor  of  the  order   r,   which 

would  render  them  very  great  when    i    is  very  small  ;   but,  it  is  essential  to      [4853] 

dbserve,  that  this  is  not  the  case,  and  that,  ifive  only  notice  the  first  poioer  of 

the  disturbing  force,  these  terms  will  not  have  the  divisor  r,  in  the  expression 

of  the   time.     To  prove  this,  we   shall  observe,  that  by  [1195,  Sic],    the 

expression  of  v,  in  a  function   of  the   time,   cannot  acquire  a  divisor  of  the 

order   r,    except  by  means  of  the  function    — 3af)idtfdQ;t  in  which  the      [4854] 


[4853'] 


*  (2739)  When  i  is  very  small,  the  divisor  i^ — JV^  [4847]  becomes  nearly  equal  to 
— JY'^,  which  is  of  the  order  — 1  [4845']  ;  consequently,  the  term  [4847]  is  not 
increased  by  this  division. 


[48506] 


t  (-2790)     If  the  development  of  the  denominator  of  ilt  [4753]  contain  a  term  of  the 

form    A,-.cos.(/ 1'-|~-')>     arising    from    u^,    it    would   introduce  in    dt    a  term  of  the  form 

Jc  [4851a] 

k.dv.cos.{iv-{-;)  ;    whose  integral  would  introduce  in    t    a  term  of  the  form   7  .sin.(w'-[-;), 

having  the  small  divisor    /,    as  in  [4851]. 


I 


I  (2791)     The  differential  of  Q  [4774fr],  relative  to  the  characteristic  d,  gives, 

d-R=— ^— dQ;     hence    fdR=^-.—fdq.  [4854a] 

Substituting  this,  and    ij.=1   [4775"]  in   ^   [1195],  we  get, 

^  =  3  «  .fn  dt.~—3a  .fn  dt  .J\\  q.  [45546] 

Now,  the  first  term  of  this  expression  has  only  one  sign  of  integration,  and  can,  therefore, 
introduce  only  the  first  power  of  the  divisor  i  [1 196',  &c.]  ;  and,  if  we  neglect  tliis  term,  we 
shall  have, 

I  =  _3  a ./n dt  ./d  q,     as  in  [4854].  ^^^^*'^ 

VOL.  III.  98 


390  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

differential  dQ  refers  only  to  the  co-ordinates  of  the  moon.     If  Q  contain  a 

[48o5]  term  of  the  form  k  .cos.  (it  -{-;),  i  being  very  small;  this  term  cannot  acquire 
a  divisor  of  the  order  r,  except  dQ  does  not  acquire  a  multiplicator  of  the 
order  i.  The  part  of  this  angle  it,  relative  to  the  moon,  must  depend  solely  on 
the  mean  motions  of  the  moon,  and  on  those  of  her  perigee  and  nodes,  when 
we  neglect  the  square  of  the  disturbing  force.  If  i  be  very  small,  this  part 
of  /  does  not  depend  on  the  moon's  mean  motion  ;  it  must,  therefore,  depend 
only  on  the  motions  of  the  perigee  and  nodes.  In  this  case,  dQ  acquires  a 
factor  of  the  same  order  as  the  motions  of  the  perigee  and  nodes,  that  is,  of 

[4850]  the  second  order  [4817,4828e]  ;  which  causes  the  term  in  question  to  lose  its 
divisor  of  the  order  r.  Therefore,  the  angles  increasing  slowly  have,  in  the 
expression  of  the  true  longitude  in  a  function  of  the  time,  a  divisor  of  the 
order  i  only  ;  and  it  is  evident,  that  this  likewise  holds  good,  in  the  expression 

[48571  ^^  ^''^  time  in  a  function  of  the  true  longitude.  But,  if  Ave  notice  the 
square  of  the  disturbing  force,  the  part  of  the  angle  it,  relative  to  the  moon's 
co-ordinates,  may  contain  the  sun's   mean  motion  ;  and  then,  the  differential 

[4657']  dQ  acquires  only  a  factor  of  the  fust  order,  or  of  the  order  m.  From 
these  principles  ice  can  judge  of  the  order,  to  which  the  several  terms  of 
the  differential  equations  are  reduced,  in  the  finite  expressions  of  the 
co-ordinates. 

6.  Upon  these  considerations  ive  shall  develop  the  different  terms  of  the 
equation  [4754].  In  the  elliptical  hypothesis,  the  constant  part  of  u  is 
represented  by,* 

[4858]  -  •  { 1  +  C"  -f  5-  7^  + 13  5  :=  constant  part  of  u  ; 

[4858'!     [3  being  a  function  of  the  fourth  dimension  in  e,  y,  we  also  have, 

[4859]  ^^'  =  «  .  { 1  — e-—  7'  +  |3'}; 

[4859]     ^'  being  likewise  a  function  of  the  fourth  dimension  in  e  and  7.     The  sun's 
[48C0]     action  alters   this  constant  part  of  u  [4858, 4964]  ;  but  a  being  arbitrary, 


*  (2792)     Neglecting  terms  of  the  fourth  order,  we  have,  in  [4826],  the  constant  part  of 

[4858a]    u    equal   to     - -{l  +  e^ -\-ll^;     and,  from  [4825],     h~  =  a .\\  —  e-  —  y^.       Adding  to 

these  the  functions  of  the  fourth  order,  depending  on    p,    (S',  they  become  respectively,  as 
in  [4858,4859]. 


Vn.i.^^6.]     TERMS  OF   q  IN  THE  DIFFERENTIAL  EQUATION  IN  u. 


391 


we  may  suppose,  that     -  .p  +  f'~  +  T7"  +  (3|      [4858]  always  represents   the 
constant  part  of  u.     In  this  case,  we  shall  no  longer  have 

h-  =  0.(1— e=— >H|3')    [4859]  ; 
and  we  shall  then  put, 

a    being  an  arhitrarij  quantity  which  becomes  equal  to  a,  if  we  exclude  the 
sun^s  action.     We  shall  then  put, 


m 


This  being  premised,  the  term 

m'.u'^ 

Q,o    3  5    or  the  expression 

becomes,  by  development,  as  follows  ;* 


1 

Â2' 


dq 

du 


s 
JFu 


'§)     [4808], 


'3 


m.  Il 
2li\u^ 


m 
2a. 


l  +  e^^+i^^  +  le'^ 

—  3e.(l+ie^+fe'^).cos.(cj;  — t.) 

+  3e'.  (l  +  e=  +  ir2+|fi'2).cos.(c'OT»  — ^') 

—  f  .  (3  +  2  m) .  e  e'.  cos.  (cv-{-c'mv  —  ■is  —  ■^') 

—  f.  (3 — 2m).ee'.  cos.(cj;  — c'mv  —  -^  +  w') 
+  3e-.cos.(2cv—2^) 

+  ^7--cos.(2gv  —  2è) 
-f-  |-e'^cos.(2c'mt?— 2'o') 

—  I-  e  y-.  cos.  (2^«  —  cv  —  2^  +  ra) 


[4861] 

[4862] 

a,. 

[4863] 

[4864] 

m. 

[4865] 

[4865'] 


[4866] 


*  (2793)  If  we  separate  the  terms  of  the  expression  of  -  [4826],  into  different 
classes;  using  the  abridged  symbols  Xi,  x^,  x^  [4866i],  whose  indices  represent  respectively 
the  orders  of  the  terms,  we  shall  have  u  [4866c],  from  which  we  obtain  —  r4866c?l, 
neglecting  terms  of  tlie  fourth  order  in  e,  7  ; 

Xi=  e. COS. (cv  —  zi);     x.2  =  e^-\-iy^— {7^.cos.{2gv—2ê)  ;     X3  =  e^.cos.  (cv—-a)',      [48666] 

[4866e] 
[4866rf] 


u  =  a-\\l-\-Xi-\-x.2-{-X3\  ; 

■.a^l—3.{x^-\-X2+X3)-\-6.{Xl''-{-2x^X2)—l0x^^. 


392  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

To  develop  the  term 
^"'"''^    'SS-^°^-(2'^-2^0,  of  the  expression  of- ^,.('J)-^^.('||)[^^^^^ 


Now,  substituting  the  values  of  x^,  x^,  x^  [48666],  in  tlie  first  members  of  [4866/— i],  and 
reducing  the  products,  by  means  of  [6,20,  7]  Int.,  we  obtain  the  second  members  of  these 
[4866e]  expressions  respectively  ;  always  neglecting  terms  of  the  fourth  order,  and  those  depending 
on  the  angles  2gv  -\-cv,  3cv,  which  are  not  retained  in  [4866]  ;  and  using  the  abridged 
notation  [4821/]  ; 

[4866/]  1  — 3.(.Ti+Xo+.i:3)  =  l—3e^—f7'^—3e.{l-lre^).cos.cV'}-iy^.cos.2gv  ; 

[iS66g]  +       6<-=    +3e^  +  3e^cos.2ci;; 

[4866fc]  +  12a;ia;3=                          — 3e.(— 46^  — 7-).cos.ct)  — f  e7^cos.(2^i'-a')  ; 

[4866i]  —     10^1^=                            — 3c.(|ca).cos.ci-. 

The  sum  of  these  four  expressions  being  multiplied  by  a^,  gives  the  value  of  m"^  [4866(/,fc]. 
Moreover,  from  [4863],  we  get  J/t"^  [4866/]  ;  the  product  of  the  two  expressions 
[4866A:,?]   gives  [4866??t],  neglecting  terms  of  the  fourth  order  ; 

[4866fc]      u-^=^a\  { l—iy''—3e.{l—ie''—7^)-cos.cv-\-3c"-.cos.2cv-{-h^.cos.2gv—^ef-cos.{2gv—cv)l; 
[4866i]    ih-^=har\\l  +  e^+7 


21    . 


r4866ml    A-  ^.^' .{l+e^+j7^-3e.(l+èe')-cos.Cf+3e^cos.2«,+372.cos.2^«-|e72.cos.(2^r-ft>) } 


«3 


[4866n]  ~2â'^'"^^^' 

X  beino-  put,  for  brevity,  to  denote  all  the  terms  between  the  braces  in  [4866m],  except  the 
first,  or  unity. 

We  may  proceed,  in  the  same  manner,  to  find  u'-^.     For,  by  using  the  symbols   y^,    y^. 
j/3  [4866^],  the  expression  of  7t'  [4838]  becomes  as  in  [4866;-];  omitting,  as  above,  the 


[4866o] 


[4866p] 


angles  •a,  ■a',  in  the  rest  of  the  calculation.  From  this  value  of  u'  we  get  u'-^  [4866*]. 
The  terms,  composing  the  factor  of  this  expression,  are  found  in  [4866< — ?«]  ;  whose  sum, 
multiplied  by  a'-^,  gives  m'=  [4866s],  as  in  [4866x]  ;  neglecting  the  terms  depending  on 
the  angle  Sc'mv — 3ra'  ; 

y,  =  c'.cos.c'?ftt)  ;         y^=e'^.cos.2c^mv; 
[4866g]  y^  = Jc'3.  cos.c'TOti+OTee'.cos.(cD  —  dmv)  — mee'. cos.  {cv-\-c'tnv)  ; 

[4866r]  «'  =  «'-'  .\l  +  yi-\-  2/2+  y  2  ]  ; 

[4866*]  m'3  =  «'-3.^  i+3.(yi+y2+y3)+3.(yi=^+2y,y,)  +  </i=h 


VII.  i.  §6]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  393 

we  shall  first  give  the  development  of 

3  m' .  u'  ''.  COS.  (2  ?;  —  2  v') .  [4866"] 

This  term,  being  developed,  becomes, 


[4866/] 


1  +  3.  (yi+  y-i  +  i/s)  =  1  +  3  m  c  e'.  cos.  (cv — c'm  v)—3  m  ee'.  cos.  (cu+cW) 

+  (3e'— |e'3).cos.c'mu  -\-3e'^.cos.2c' mv; 

3i/^^=     +2e'2  +|e'2.cos.2c'mr;  [4866u] 

6)/i(/o=  +-2/.e".cos.  c'tod;  [4866d] 

J/i^=  + 1 e' 3. cos.  c'm 2';  [4866u>] 

,  ,  Cl  +  3e'2  +  3e'.(I  +  |e'2).cos.c'mt>+8e'3.cos.2c'mr  ) 
M'3  =  a'-3.)    y-       ~         V  '  \       o         '  ^        I     '       ^^  L4866a:] 

(   -["3»ict -cos-^CD  —  c  mv)  —  3mee. cos. {cv-\-cmv)\ 

=  «'-3.  Sl  +  r|;  [4866)/] 

l+Y    being  used,    for  brevity,   to  denote  all   tlie    terms  between    the  braces,   in    [4866x].    [48662] 
Multiplying  together  the  expressions  [4866»,  y],  and  their  product  by   m'  ;  then  substituting 

_a 
m 


[4865],  we  get. 


2  A2.  ((3 


=  ^  .{1  +  X+  Y+XYl.  [4866a] 


Now,  XY  is  of  the  second  order;  and,  in  finding  its  value,  retaining  the  same  angles  and 
terms  as  in  [4866],  we  may  use  the  following  expressions,  which  comprise  the  chief  terms  of 
X,    Y  [4866«,y]; 

X^e--j-^7^  —  3e.cos.cv;  F=|e'^+ 3e'.cos.c'mv.  [4866p] 

Now,  taking  the  terms  of  Y.  and  multiplying  them  separately  by  X,  we  get, 

|ê'2.  X= — lee'^.cos.ci' ;  [4866y] 

.3e'.cos.c'mD.X=.3e'.  (c-4-ï7^) .  cos.  c'm  r  —  %  ee'. cos. {cv-\-c'mv)  —  |ee'.cos.(CT — c'mv).     [48666] 

The  sum  of  the  expressions  [4866y,  (5]  is  equal  to  the  value  of  X  Y,  which  is  to  be 
substituted  in  [4866a]  ;  moreover,  the  sum  of  the  terms  hctiveen  the  braces  in  [4866m,  a?], 
decreased  hij  unity,  is  equal  to  the  value  of  l-{-  X-\-  Y.  Hence  we  find,  that  the  terms  of 
[4866a,  or  4866],  between  the  braces,  are  equal  to  the  sum  of  the  terms  between  the  braces  [4866e] 
in  [4866m, 1],  added  to  the  second  members  0/ [4866y,  5],  and  decreased  by  unity. 
Connecting  the  similar  terms,  we  find  the  result  of  this  calculation  to  be  the  same  as  in 
[4866]. 

VOL.  III.  99 


394 


THEORY  OF  THE  MOONj 


[Méc.  Cél, 


/(l_|e'2— 4mV)  .cos.(2i'— 2my) 
+ 1  e'.  cos .  (2  V — 2  mv — c'mv-\-^') 
-^e'.cos.(2  V — 2mv-j-c'mv — -'') 
+  2me.cos.(2î; — 2mv-\-cv — w) 
— 2  me. COS.  (2 « — 2m  v — cv-\--^) 

\  +  y  e'l  COS.  (2  V — 2  m  v — 2  c'm  d+2  i^') 

I — y  mee'.cos.(2î; — 2?tt« — cv — c'mw+^+^')\ 
[4867]     3»i'.M'^cos.(2u -2t;')=^-(  +  V ^^«'- cos.(2w— 2mt)+c«— c'm«— ^+53')  ^* 

\+  ^mee'.  cos.(2'«; — 2m  w — cw-f  c'm«+ra — -n')/ 
- 1  mee'.  cos.(2« — 2  m  tJ+c  i)-f  c'm?) — œ — 33')  ) 

'  +  |m.(3+8m).e^cos.(2cz;— 2v+2»ii;— 2^) 
— Jm.(3— 8m).e-.cos.(2c«+2«— 2m?;— 2^) 
+  ^my".  cos.(2gv—2v-{-2mv—2à) 
— J:m7^cos.(2^?;-f2y — 2mv — 2è) 

\ — |-me>^cos.(2«— 2mîJ— 2^-?;+ci;4-2t'— c=)/ 


3  m' 


1 

2 

3 

4 

5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 


[4867a] 

[48676] 

[4867c] 
[4867rf] 

[4867e] 
[4867/] 

[4867g-] 

[të67h] 
[4867«] 


*  (2794)  Using,  for  brevity,  the  value  of  v^  [4867e],  putting  also  «^  equal  to  all  the 
remainin'^  terras  of  the  second  member  of  [4837],  except  the  first  mv,  we  shall  have  v',  as 
in  [4367/]  ;  always  omitting,  for  brevity,  the  symbols  a,  ra',  as  in  [4821/].  Substituting  this 
value  of  v'  in  the  first  member  of  [4867^],  and  developing  by  means  of  [24,43,  44]  Int.,  it 
becomes  as  in  [4867A]  ;  observing,  that  v^  is  of  the  first  order,  v.^  of  the  second  order, 
and,  that  some  terms  of  the  third  order  are  neglected.     Substituting  in  [4867/t]  the  value 

2v^= Sm^.e^. sin.^cu  +  167« ee'.sin. c«. sin. c'?n«  —  8e'^.sin.2c'?»i)    [4867e], 

and  reducing  it,  by  means  of  [l,17]Int.  ;   also,     2v^+2v2  =  '2v'—2mv      [4867/],  it 

becomes  as  in  [4867 i]  ; 

tijr= — 2me.sin.ci)  +  2e'.sin.c'm!;; 

cos.(2i)  — 2«')=cos.{(2t)  — 2mî;)  — (2ui+2î)o)| 

=  cos.  (2w,+  2i'2).cos.(2«  — 2m«)4-sin.(2ri4-2î)2).cos.(2a— 2mj)) 
=  (^l—2vi^).cos.{2v  —  2mv)  +  {2v,-i-'2v.2).sm.{2v—2mv) 

_f  (l_4»iV-4e'2)+4mV.cos.2CT+4c'2.cos.2cW)  ^^^        __2,ftt,) 
I      +8mee'.cos.(c« — c'mv) — Smve.cos.{cv-\-c'mv)  y 

+  {2v' — 2mv\.sin.{2v  —  2?fti'). 


VII.  i.  >^S  6]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  w.  395 


We  must  multiply    this  function  by 


2/1= 


;     and  we  have  this  factor,  by     [4868] 


We  must  substitute,  in  the  last  line  of  this  expression,  the  value  of   2v' — 2m v,    whicli  is 

easily  deduced  from  the  second  member  of  [4837],  by  neglecting  the  first  term     mv,    and     [48674] 

doubhng  the  remaining  eight  terms.     We  must  then  reduce  the  products  of  the  sines  and 

cosines  of  this  function,  by  means  of  [17,  20]  Int.,  as  in  the  following  table  ;  in  which,  the 

terms  of  column   1,  corresponding  to  the  different  angles,  are  taken   in  the  same  order  as 

in  [4867;'],  namely  ;  the  first  five  terms  in  the  same  order  as  in  the  first  and  second  lines  of 

[4867i]  ;  and  the  remaining  eight  lines  as  in  2  i'' — 2mv  [4837,  4867A:].     We  may  observe, 

that  a  term  is  neglected  in  line  9,  depending  on  the  angle    2v —  2mv-\- 2gv — cv,  which  is      [4867i] 

not  expressly  retained  in  [4867]  ;  also  a  term,  of  the  order  e'^,  inline  10,&ic.; 


(Col.l.) 

1 

2 

3 

4 

5 

6 

7 

8 

9 
10 
11 
12 
13 


(Col.  9.) 

(  1  —4)n^e^ — 4c'2).cos.(2y— 2m«) 
4-|-mV.cos.(2CT — 2v-\-2mv)-\-^.m.^e^.cos.(2cv-\-2v — 2mv) 
-\-2e'^.cos.{2v—2mv—2c'mv)-'r2e'^.cos.{2v—2mv-i-2c'mv) 
-}-4mee'.cos.{2v — 2mv — cv-{-cfmv)-{-4mee'.cos.{2v — 2mv-\-cv — c'mv) 
— 4mee'.cos.{2v—2niv — cv — cfmv) — 4mee'.cos.(2u — 2mi;-f-c«+c'»i«) 
4-2?«e.cos.(2ii — 27nv-\-cv) — 2me.cos.(2y — 2mv — cv) 
-|-?'«c^.cos.(2ci; — 2v-\-2mv) — fme^.cos.(2c2;+2i' — 2mv) 
-{-imy^.cos.{2gv — 2v-{-2mv) — i7Hy~.cos.{2gv-^2v — 2mv) 
— .^mej'^.cos.(2f — 2mv — 2^y-j-cu)-j- Sic. 
-|-2e'.cos.(2y — 2mv — c'mv) — 2e'.cos.(2r — 2mv-j-c'mv)-}-hc. 
—2mee'.cos.{2v~2mv—cv—c'mv)-^2mee'.cos.{2v — 2mv-\-cv^c'mv) 
— 2ffiee'.cos.(2« — 2mv—cv-{-c'mv)-{-2mee'.cos.{2v—2mv-{-cv — c'mv) 
-{-îe"^.cos.{2v—2mv—2c'mv)—^e'^.cos.{2v—2mv-^2c'mv). 


[Terms  of 
C03.(2i7-20').  J 


[4867m] 


Toobtain  the  expression  [4867],  we  must  multiply  this  value  of   cos.  (2d  —  2d')    [4867m], 

by  Sm'.u^,  or  3m'.  a'-^.  (l  +  Y)  [4866(/]  ;  by  this  means  all  the  terms  will  have  the  common 

.  3m'      ,.,       ,  .  ,  •     r .        -,  [4867n] 

lactor    —,    like  that  without  the  braces  m  [4867]  ;  and  the  terms  of  this  expression  within 

the  braces  will  be  obtained,  by  multiplying  the  function  [4S67m]  by  1  +  F;  or,  in  other 
words,  by  multiplying  the  functions  [4867m]  by  Y  [4866x,  y],  and  reducing  the  products  [4867o] 
as  in  [4867r],  then  adding  together  the  two  functions  [4867?«,  r].  In  the  first  column  of 
[4867?-],  we  have  given  the  terms  of  Y  [4866-r,y]  ;  and,  in  the  second  column,  the  terms 
of  [4867m],  by  which  they  are  multiplied:  the  third  column  contains  their  products, 
respectively.  The  numbers  in  column  2,  refer  to  the  numbers  in  the  margin  of  the  lines  t^^^'^-P] 
of  [4867m],  putting  one  accent  to  denote  the  first  term  of  any  line,  tivo  accents  for  the 


396 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


putting  e'  equal  to  nothing,  in  the  preceding  development  of 


2h\i 


[4866], 


[4860]      aiTid  \^y  multiplying  this  last  quantity  by     —,       We    shall    thus    have,    very 
nearly,  by  neglecting  quantities  which  remain  of  the  order    m'   after  the 


[4869'] 


[4867c] 


integration,* 


[4867r] 


second  term  of  the  same  line,  &i'C.  Thus,  6'  denotes  the  term  2ffîe.cos.(2i' — 2mv-\-cv)i 
and  6",  the  term  — 2me.cos.{2v — 2mv—cv).  This  method  of  distinguishing  the  terms 
ivill  he  frequently  used. 

(Col.  3.) 

Products  of  these  terms. 

-j-fe'^.cos.(2?; — 2  niv) 

-(-|é'.cos.(2ii — 2mv — c'mu  )-|-fe'.cos.(2t) — 2mv-\-c'mv) 
-\-'3mee'  .cos.{2v-2mv-\-cv-c'mv)-\-^mee'  .cos.{2v-2mv-\-cv-\-dmv) 
— ^mee'.cos.(2,v-2mv-cv-c'mv)—Zmee'.cos.{2v-2mv-cv-\-c'mv) 
4— 3e'^.cos.(2y — 2mv — 2c'mt>)-|-3e'^.cos.(2i' — 2mv) 
— 3e'^.co3.(2u — 2mv-\-2dnn^ — 3e'^.cos.(2y — 2mv) 
4-|e'2.cos.(2i;— 2my— 2c'my)+fe'2.cos.(2u— 2?nj)4-2c'?ni;) 
-\-^mee  .cos.{2v-2mv-cv-{-c'mv)-\-^inec' .cos.(2,v-2mv-\-cv-c'mv) 
— i^mee' .COS. {2v-2mv~cv-c'mv) — ^mee  .cos,.[2,v-'2'mv-\-cv-{-c  mv^ . 

Connecting  together  the  terms  of  [4867m, r],  depending  on  the  same  angles,  we  find,  that  the 
coefficient  of  cos.(2y — 2?nu  +  2c'»i«^)  vanishes,  and  the  rest  become  equal  to  the  function 
between  the  braces  in  [4867],  conformable  to  [4867o]. 

*  (2795)     The  method  given  by  the  author,  in  [4869],  is  evidently  correct.     For,  if  we 

m'.u'  3 


(Col.  1.) 

(Col.  3.) 

Terms  of  Y  [48C6r]. 

Terms 

of 

[4867,n] 

+  |e'2 

r 

-[- 3  e'.  cos. c'm  y 

1' 

6' 

6" 

10' 

10" 

|c'^.cos.2(;'7rtw 

1' 

-|-3?î2ee'.cos. (ct) — dmv) 

1' 

— 3mee'.cos.(cy-|-c'mt') 

1' 

I 


[4869a] 
[48696] 


,  we  get  u  =  -,,  whence,     ——7 


—,  ;     multiplying  this  by 


2/t9.„3 


We  shall  not,  however,  be  under   the    necessity  of  using  this    process, 


[4869c] 


put  e'  =  0,  in 

1 

eives     J77T — ;. 

1  a3 

because  we  have  already  given  the  value  of    2^;5~^  =  ^  •  (1  +  -^)      [4866m, 71]  ;    and,  if 

we  multiply  this  by  the  function  [4867],  we  shall  obtain    [4S70].      In  the  first  place,  the 
factors  without  the  braces    -^,      ;^,     being  multiplied  together,  produce, 

3       m'.a3  .3        _2  , 

—  .  -— -  =  —  .  «I      [4865]  ; 


VII.  i.{.G]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u. 


397 


/ 


il+e^+iy^—èe'^).cos.{2v—2mv) 


1 


_i(34-lm).t.(l-}-^e-— Je'2).cos.(2y— 2mi'— CD+n)  \  2 

— i(3 — 4m).c.cos  [2v — 2mv-\-cv — w)  ;{ 

-|-Je'.cos.(2r — 2m  v — c'm  v-j-:^')  4 

— ie'.  cos.(2u — 2mv-]-c'mv — ra)  /  5 


— --^J-(14-2?«).ee'.cos.(2i' — 2mv — cv — c'mn-f  a-f-^') 
-'\'~{  1  — 2  m)  .e  c'.  COS. (2  v — 2  m  «-j-c  v — c'mv — ra-f-^) 


6 

7 


^-.COS.(2«-2w')=±!^./  +  i  (3+2m).ce'.cos.(2t)— 2mj;— CD+c'mD-J-za— Î3')  \  .  8     [4870] 


2li\u 


2a 


+  T  (3 — 2/?«).ec'.cos.(2^; — 2 m d-(-c y -f  t''« ^ — « — si') 
l+-V.e'2.cos.(2r— 2?nt)— 2c'mz)+2îî') 
+i(6+15m+8ffl2).e2.cos.(2ct)— 2t)+27«i'-2i3) 
+K6— 15m+8waj.g2_£.os.(2cr4-2t)— 2mj;— 2-51) 
+Ï  (3+2  ?«)  .y-.  cos.(2^  j;— 2  t)-f  2  m  i-— 2  è) 
+}  {3—2m).y~.cos.{2g v-\-2v—2mv—2ê) 


9 
10 
II 
12 
jl3 
14 


The  term 


^^^,.cos.(.-.),    of  the  expression     -,^.(f 


— f  (2+m).e7a.cos.(2z!— 2m«— 2^c4-ct;+2()— ^)   /  15 


hh 


lis 


[4808], 


[4871] 


which  is  the  same  as  the  common   factor  of  [4870] .     Moreover,   the  terms  between  the 

braces  in  [4870],  are  represented  by  the  product  of  the  terms  between  the  braces  in  [4867], 

by  l-{-X  [4866n]  ;    or,  in  other  words,  this  product  is  equal  to  the  terms  between  the     ^  ■' 

braces  in  [4867],  added  to  the  function  [4S69c].     TJiis  last  function  being  the  result  of  the 

product  of  these  terms  of  [4867]  by  the  the  quantity  X;  and  it  is  obtained  in  the  following 

table,  which  is  similar  to  [4867r].     The  first  column  contains  the  terms  of  X;    the  second,    [48fi9t/'] 

the  terms  of  [4867],  and  the  third,  the  corresponding  products,  reduced  in  the  usual  manner, 

and  using  the  accented  number   1',  to  denote  the  first  term  of  the  first  line  of  [4867],  as 

in  [4867 5]  ; 


VOL.   III. 


100 


398  THEORY  OF  THE  MOON  ; 

[4871']     gives  t!îe  following  ;* 


[Mtc.  Cv\. 


[4869e] 


[4869/] 


[4869e-] 


(Cl.  1.) 

Terms  of  X  [4866jn,n] 


—  3e.cos.cv 


-f-3e^.  cos.âcw 
-{-^■y^.cos.2gv 

— |cy^.cos.(2^y — cv) 


(Col.  2.) 

Terms 

of 
[4867]. 

1' 


1' 
1' 
2 
3 
4 
5 
13 
1' 
1' 
1' 
4 
1' 


(Cul.  3.) 

Products  of  these  terms. 


[4870a] 


[48706] 


[4870c] 
[4870rf] 

[4870e] 


-f-e^.cos.(2  V — 2  mv) 
-j-.l7^-cos.(2); — 2mv) 

-Jc.cos.(2t>— 2  m  y+CD)—fe. (1—1  e'2).cos.(2t>— 2m  r—cr) 

-?^^ee'.cos.{2v-2mv-cv-c'mL-) — --j'-ee'.co3.(2tf — 2mv-}-cv—c'mv) 
4-.?Ée'.cos.(2« — 2mt;-cz)-fc'mi')+3ee'.cos.(2î) — 2mv-\-cv-\-c'mv) 

-3  m  e^. COS.  (2  V — 2/»!;) — 37ne^.cos.{2cv-\-2v — 2  m») 
-\-3me^.cos.(2v — 2m,v)-\-3me^.cos.(2cv — 2v-\-2mv) 

-f  m  e  y^.cos.(2  v — 2  m  v — 2^-  v-\-c  v) 

■|(?.cos.(2i' — 2  my — cv) 
-|-5  e-.cos.  (2  c  I' — 2 1'-|-'~  ni  v)  -\-^  e^.cos.(2f  y-j-2  v — 2  m  v) 
-\-^y-.cos.{2gv — 2v-{-2mv)-\-^y^.cos.(2gv-{-2v — 2m  v) 
-|-|-me7^.cos.(2!; — 2mv — 2gv-\-cv) 

-|e7^.cos.(2D — 2mv — 2gv-\-cv). 

Now,  adding  tlie  function  [4839e]  to  the  terms  between  tlie  braces  in  [4867],  we  get  very 
nearly,  the  expression  between  the  braces  [4870].  Tiiere  are  some  shght  differences,  of 
the  same  order  as  that  of  tlie  terms  which  we  have  usually  neglected.  Thus,  the  term 
—  'im^e^,  in  the  coefficient  of  line  1  [4867],  is  neglected  in  [4870].  The  term  — 2me, 
in  hne  5  [4867],  is  connected  with  the  ftctor  (l+lt^ — i^'^)  in  line  2  [4870],  which  arises 
from  the  chief  terms  of  this  coefficient  in  [48G9e]  ;  but  this  merely  introduces  terms  of  the 
sixth  order.  Finally,  we  may  observe,  that  a  similar  factor  might  be  introduced  in  the 
coefficient  of  line  3  [4870]. 

*  (2796)  Proceeding  in  the  same  manner  as  in  note  2793,  and  retaining  terms  of  the 
second  order  only,  we  get,  from  [4866c]  u~*=câ.\l — 'i.{xi-\-x.2)-\-l0xi^\;  substituting 
in  this  the  value  of  10ccj^:=  10  e^.cos.^<:«  =  5  e^+5e^cos.as;  ;  also  the  value  of  x^-j-x.^ 
[4866i],  we  get, 

u~'  =  a'.  \  l-\-e^ — j^ — 4e .  cos.  cv-\-5  e^.  cos.  2  c  j;  -[-}'"•  cos.  2gvl. 


Multiplying  this    by 


9  m' 


■  \l  +  e"~^y~)     [4863],  we  obtain, 


9) 


„,„    ,  =  -—^ — .ll-\-2e^ — 4e.cos.ct)-)-5e^.cos.2ct)4->'^.cos.2fi-i'i 

8^2.  ,j4  8(,^         (        I  I  I    /  to      s 

Again,  from  [48667,?-],  we  have  successively,    6w^^  =  3  e'--j--3e'^.cos.  2c'm  y  ; 
=  a'-'.|l+3e'2-|-4e'.cos.c'm»-[-7c'2.cos.2c'm»}. 


VIl.i.§6.]    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  m.  399 


8«,  ■  a 

__.cos.(«— r)=<^^ji^ji_e'_cos.(i'— mz)+c'm«— ^')         /•        2       [4872] 

,   2~lh     a    ,  .  t         .     i\ 

-1 -.e.  cos.(i' — m  V — c  m  v-I-t^  ) 

8  a,     a 


[4870/] 


If  we  denote  tlie  factors  between  the  braces  in  [4870c, e]  by  1-|-X,,  l  +  ^u  respectively, 
their  product  will  be  l-f-^i+î^'i+^i^V»  ^Y  noticing  only  the  chief  terms  of  X,,  F,, 
we  have, 

Xi  Yi=  ( — 4e.cos.ci').(4e'.cos.c'HM')  =  — Sec'. cos. (c« — c'mv) — 8e e' .cos. [cv-\-c'mv).         [4870g] 

Adding  these  terms  of  Xj  Fj,  to  those  of  l+^u  l  +  ^i  [4870c,  e],  and  decreasing  the 
sum  by  unity,  we  get  the  expression  of  1-j-Xj-f-  Fj  +  Xj  Fj,  to  be  used  in  the  product  of 
the  functions  [4870c,  c],  which  becomes, 

C 1 -j-2  e--)-3  e'^4-4  c'.  cos. c'm« — 4e.cos.cv  '\ 

9m'. u"^        9m'.  a'        ),-g  ^        ,0  „         1  n   ">  0/        V 

g^-^  =g^^^  •  )    +^^-cos.2cv-j-f.cos.2gv-frle~.co5.2c'mv'>  .  [i870h] 

(_  — 8  c  e'.  cos.  (c  V — c'in  v) — 8  e  e'.  cos.(c  v-{-c'm  v)  ) 


m .  w 


Substituting  the  value  of     —7—     [4865],  in  the  first  factor  of  this  expression,  it  becomes, 

9m'.  a*        a  —  ^O' 

8^4- l'A; -o  [4870,-] 

which  is  of  the  fourth  order  [4842,4843]  ;  therefore,  in  finding  the  value  of  cos.(«) — v'),  we 

need  only  to  retain,  in  general,  the  terms  of  the  first  order  ;  except  in  those  depending  on 

the  angle    v  —  mv  ;    in  which  greater  accuracy  is  required  [4874].     Hence  we  may  neglect     [4870/i;] 

«0  [4867/"],  and  we  shall   have  the  value  of  cos.(«; — v')    [4870»i],  by  proceeding  as  in 

[4867^,A].     Substituting  in  this  the  value  of   I'l^^  2e'.  sin.c'wt)    [4S67e],  it  becomes  as  in 

[4870n].     It  being  unnecessary  to  notice  other  terms  of  a  higher  order,  or  such  as  depend  on     [4870i] 

angles  which  differ  from  those  in  [4872]  ; 

cos.(r — r')=(l — irj^).cos.(i' — ?«t))-|-i'i-sin.(v — mv)  r4870   1 

=  (I — fc'^).cos.(t) — mv) — c'.cos.(« — mv-{-c'mv)-\-c'  .cos.[v — mv — dm  v).  r4870n] 

The  four  terms  of  which  this  expression  is  composed,  being  multiplied  by  the  terms  between 

the  braces  in   the    function    [4870/i],    produce   respectively  the   terms   in    the  four  lines 

[4870o — r].     Their  sum  is  given  in  [4870^];  to  which  we  must  annex  the  common  factor 

9m'.  vJ^ 
[4870ï] ,  and  we  shall  obtain  the  corresponding  terms  of       '  ,^.cos.{v — v),   as  in  [4872].   We 

shall  hereafter,  in  [4870/ — w],  see,  that  the  neglected  terms  have  much  less  effect,  in  the 
value  of  u,  than  those  we  have  explicitly  retained  ; 


400  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4872']     -  being,  hy  the  preceding  article  [4843],  of  the  order  m'  ;  the  two  first  of 

[4873]  these  terms  become  of  the  order  »t^  by  the  integrations.  The  inequality, 
depending  on  the  angle  v — mv,  is  remarkably  loell  adapted  to  the  determination 
of  the  Slut's  parallax,  by  means  of  the  ratio     -.       It  is,  therefore,  important 


[4874] 


[4870o]  1 
[4870;>]  2 
[48709]       3 


[487  0<] 


(Coi.i.)  {Col.  a.) 

(l-j-2c^-f-3e'^).cos.(«) — mv)-\-2e'.co'3,.[v — mi'-f-c'mt')-l-2e'.  cos.(r — mv — c'mv) 

—  e'^.  cos.(i) — mv) 

—  e' .  COS.  (v — m  v-\'C'm  v) 
[4870r]        4     j  J^e'  .cos.{v—mv—c'mv). 

[4870«]  (l-|-2e"-4-2e'-).co3.(i! — mv)-\-e'.cos.{v — mv-\-c'mv)-\-^e'  .cos.{v — mv — c'mv). 

If  we  compare  the  terms  [4872]  with  the  assumed  form  [4846],  we  find  the  values  of  i, 
corresponding  to  them  respectively,  are  i^l — in,  i:=l — m-|-c'm,  i=l — m — cm;  and, 
as  c'  hardly  differs  from  unity,  they  are  very  nearly  represented  by  i^\ — m,  i=l, 
i  =  \—2iii.      The  corresponding   divisors,  in  the   value  of  u   [4847],  are  of  the  orders 

[4870m]  (1 — m)~ — JV^  \—N^,  (1— 2m)2 — N~  ;  and,  as  JV-  differs  from  unity  by  quantities 
of  the  order  m^  [4815'],  these  divisors  will  be  respectively  of  the  orders  m,  m^,  m.  In 
consequence  of  these  divisors,  the  part  of  the  first  term  [4872]  which  is  independent  of  c,  e', 
is  reduced  from  tlie  fourth  to  the  third  order  ;  the  second  term  is  reduced  from  the  fifth  to  the 
third  order  ;  and  the  third  term  is  reduced  from  tlie  fifth  to  the  fourth  order.  Several  terms 
of  the  function  [4870t",  or  4872],  are  not  increased  so  sensibly  in  the  value  of  m,   and  they  are 

[4870tt]  therefore  neglected.  Thus,  the  term  — 4e.cos.cv  [4870/(1,  being  multiplied  by  the  first 
term  of  [4870»],  produces,  in  the  function   [1872],  the  following  expression, 

[4870jr]     |.^  .  -.( — 4c.cos.cy).cos.(!; — mv)  =  — ~.^  .  -.2c.{cos.(ci' — v-\-mv)-\-cos.{cv-\-v — mv)\. 

r4670vl  corresponding,  in  [4846],  to  i  =  c — l-f'">  i^c-\-\ — m,  and  as  c=l — f»«~  nearly 
[4828e],  these  terms  will  not  render  the  divisor    i^ — JV^    small  [4847]. 

We  may  observe,  that  the  term  treated  of  in  [4871],  occurs  in  [4S08],  under  the  form 

3wi'  w'M 

.(3— 4«-).cos.(v — v'),    and   in    [4754],  with  a  dilierent  sign,  and  under  the   !brm 


[4870^'] 


8ui 

3m'.i('-l     ,_  ,     o,  ,  ,,  y»ï'.!(''  /  ,  .      n\  /  /\  1  •     1  1  1  •  o 

.(3 — 4s-).cos.(t' — v),    or,  .(1  —  *;.s-j.cos.(y — v  )  ;      whicli,    by   neglectmg     s", 

becomes  as  in  [4871].     Now,  by  [4618],  wc  have, 

[4870Z]  _4,a__£-/.cos.2(5-f-d)  =  _f  ,.2_£y5.cos.(25-.-2<!)  ; 

which  contains  the  constant  quantity    — f^-;    so  that  we  might  multiply  the  function  [4871] 
[4870z']     by  1— §r,  which  would  change  the  foctor  (l+2(;'-+2e'-2)  [4872]  into  l-l-2e-+2c'2— f/^. 


VII.  i.  §6.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  401 


to  determine  this  inequality  with  particular  care  ;    and,  for  this  purpose,  we      [4875] 
shall  carry  on  the  approximation  so  as  to  include  terms  of  the  order  m*. 

We    shall  now  develop   the  term     \j)-j;r~Yj~^  of  the  equation  [4754]. 
In  the  first  place,  this  term  contains  the  following,*  —  ^-^^.--.s'm.(2v—2v').      tl87C] 

.sin. (2d — 2v'),  by  increasing    2v  by  a  right  angle, f     [4876'] 


We  shall  have 


*  (2797)     This  is  produced  by  the  first  term  of  [4809]. 

t  (2798)  We  may  change  2y  mto  any  other  angle,  as  2 v  in  [4867^ — r,  4867,4870], 
without  altering  the  angles  mv,  gv,  cv,  c'mv,  as  is  evident  by  the  mere  inspection  of  the 
process  of  calculation  in  [4767^,  &.c.].  This  change  being  made  in  [4870],  and  then 
putting    2  V  =  2 1"-]- 90'',   its  first  member  becomes, 

-^u^-'^-^-'-^''^^     ^^  In  [4876']. 
In  the  second  member  of  [4870],  we  must,  by  the  same  process,  change  any  term  of  the 
form    cos.(2!;-l-p)    into    — sin.(2«4-|3)  ;     and  any  one  of  the  form     cos.(3 — 2r)    Into 
-|-sin.(3— 2v).     Hence  we  get,  by  changing  the  signs  of  all  the  terms  of  [4870],  and 
neglecting  the  symbols  è,  ct,  -ô/,  as  In  [4821/], 


?^';sin.(2«-2.')=|^ 
2h\u^        ^  ^      2a, 


/(I  +e2+i  5-2—1  e'2).sln.  (2  v— 2  m«) 
— |(3+4»?).e.(l+|e2— Je'2).sin.(2î>-2mD-cî)) 

-5(3 — 4m).e  .sin.  (2  \i — 2  m  vA-c  v) 
-|-Je'.  sin.(2t) — 2mv — (^mv) 
I  — J  e'.  sin. (2  v — 2  m  v-\-(!m.  v) 
\  — -i-{\  -|-2  ni)  .e  e'.  sin .  (2  « —  2  mv — c  v — dmv) 
I  — %'-(  1  — 2 ni).ee'. sin  .(2 v — 2 m v-\-c v — c'mv) 

-\-  1  (.3-l-2OT).eÊ'.  sln.(2y — 2mv — cv-{-dmv) 
\  -\-  i  (3 — 2  m)  .e  c'.  sin . (2 v — 2 m v-\-c v -f  c'm v) 
I  +-¥•  e'  ^.  si  n.  (2  r — 2  7n  v — 2  c'm  v) 

-l(6+15?n+8m2).e2.sin.(2ct)— 2i}+27n«) 

+i{6—l5m4-8m^).e^.s:ii.{2cv+2v—2mv) 
-i  (3+2  m).y~.  s\n.{2g  v—2  v-\-2  m  v) 

+^{S—2m).y-.sm.{2gv+2v—2mv) 
\ — ^  (6-|-3 in).ey'^. sin. (2 v — 2 m v — 2^r-f-cy) 


[4875a] 

[4876o] 
[4876t] 

[4876c] 
[4876rf] 


1 

2 
3 

4 
5 
6 

7 

8      [4876c] 

9 
10 
11 
12 
13 
14 
15 


VOL.   III. 


101 


402                                              THEORY  OF  THE  MOON  ;  [Méc.  Cél- 

3m'  u'^ 
ill  the  preceding  development   of      rr^— 5.cos.(2« — 2v')  [4870].      We  must 

then  mutiply  this  development  by,* 

•— ce.(l+ie^ — J-7-).sin.(ct; — 3j)  v  i 

+  icelsin.(2ctJ— 2^)                 I  2 

[4878]                                             rfM          I        ,       ^    .      ,„           q    .                       (  „ 

«</«;       1  I 

+  ia-7^sin.(2^i;— 20)                |  4 

, — ±ef.sm.(2gv—cv—2ê+z!)  I  5 


*  (2799)     The  differential  of  [4826],  relative  to  v,  gives,  by  neglecting    «,    6,    as  in 

[4821/], 

[4878a]  ~  =  a-K{—ce.(l+e^).sm.cv+^gf.sm.2gvl; 

dv 

and  if  we  neglect  terms  of  the  third  order  in  all  the  coefficients,  except  those  which  are 
connected  with  the  angle      2gv—cv,     we  obtain  from    u     [4866c],  the  following  value 

[48786]     of     -     [4878c,  tZ],     by  observing,    that     a-i^E^.cos.^cf  =ie2+ie^.cos.2cy      [4866è]. 
w 

We  may  remark,  that  the  author  has   retained,  in  the  coefficient  of  cos.  cj;,    a  term  of  the 
third  order  e^,  but  has  neglected  others  of  the  same  order,  as  will  be  seen  in  [48846]  ; 

[4878c]  i^a.{  l-(x^+x,+x,)+{x,i-x,+x,y-{.T,-j-r,+x,f+hc.l 

u 

[4878d]  =a.\{l—ie-—lf)—e.(l-\-e").cos.cv+he^.cos.2cv+if.cos.2gv\. 

Multiplying  together  the  two  expressions  [4878a,rf],  we  find,  that  the  factor  without  the  braces 
becomes  a-^.a  =  1  ;  so,  that  we  have  only  to  notice  the  product  of  the  factors  between  the 
[4878e]  jjj.j^(.g3  -pj-jjg  jg  jjQj^g  jjj  (i^g  following  table  ;  in  which  is  given,  in  column  1,  each  of  the  four 
terms  of  the  function  [4S78(f]  ;  and  the  corresponding  products,  by  the  function  [4878a], 
are  given  in  column  2,  on  the  same  lines  respectively  ; 

(Col.  2.) 

— ce.(l-\-ie'^ — ^■)'^).sm.cv-\-^g'y^.  sin.2^v 
4-i  c  e^.  sin.2  c  v — | g  c  -f.  sin. (2^  v — c  v) —  &;c. 
■\-\c  e^.  sin.cu — \  ce^.  sin.3c  v 
-\-\ct  -f.  sin. (2^  t —  ci))-f-&ic. 

Connecting  together  the  similar  terms,  and  putting    c  =  l,    g^=\,    in  those  of  the  order 
e  7-,    it  becomes  as  in  [4878]. 


(Col.  1.) 

[4878/] 

l-|c"-i7' 

[4878^] 

— c.(l4-«^)-cos.cw 

[4878/.] 

-|-Je2.cos.2c«; 

[4878i] 

4-^7®.cos.2^w 

VII.i.§6.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u. 

Then  we  shall  have,* 

/cc.(l-f^.[2— 19m].e=— |e'2).cos.(2u— 2m»— cv+ra) 
/  —  ce.cos.(2« — 2mv-^cv — «) 
I  +  J.cce'.cos.(2t) — 2mv — cv — c'Mt)-j-ra-|-w') 
\ — |-.cee'.cos.(2i; — 2mv-\-cv — cfmv — ra-j-w') 

I — ^.cee'.cos.(2D — 2mv — cv-\-c'mv-\-zi — •ra') 

3m'A3  du  .     ,^       ^  ,,      3in     +h-cee.cos.{2v—2mv-\-cv-{-c'mv—-a—a') 
— nT^T"  -T  •sin.(2u — 2t)')=: — ./ 

2''-"'  ''"  4"'  \— 2c.(I+m).e2.cos.(2c?;— 2«+2mu— 2«) 


403 


4-2c.(l— m).e^.cos.(2ci)4-2t) — 2mv — 2a) 

-{-  4  m  c.  e^.  COS.  (2  v — 2  m  v) 

—  tgf.co5.{2gv—2v-\-2mv—2è) 

-}-igy^.cos.{2gv-\-2v—2mv-\-2è) 

_|_  J.(2 — 5m)  .e  y^.  cos.(2u — 2mv — 2gv-^cv-\-2ô — ro)/ 


1 
2 
3 

4 

5 

6 

7 

8 

9 

10 

11 

12 


[4879] 


*  (2S00)     If  any  term  of  [4876t;],  be  represented  by 

.  A  .  sin.  V, 

2a,  ' 

and  any  term  of  [4878],  by    .^'.sin.F',    the   product  of  these  two  terms,  changing  its  sign, 
will  represent  the  corresponding   part  of    —       '  ^  ■— .sin.(2t; — 2v')     [4879],  which,   by 


reduction,  becomes, 


^^.{AA'.cos.{V-\-V')—AA'.cos.{Vy^V')l. 


The  factor  of  this  expression,  without  the  braces,  is  the  same  as  in  [4879]  ;  consequently, 
the  terms  within  the  braces,  must  arise   from  the  terms 

A  A',  cos.  (  V+  V)  —A  A'.  cos.(  F«=  V) . 

These  terms  are  computed  in  the  following  table,  neglecting  quantities  of  the  third  order 
in     e,     e',     y,     except  they  depend  on  the  angles 

2  V — 2  m  vzhc  v-\-  zs,         2  v —  2  m  v — 2g  u-j-c  v-\-2  ê — «. 

The  numbers  in  the  first  column  refer,  respectively,  to  the  five  terms  or  lines  of  [4878]  ; 
and  those  in  the  second  column,  to  the  terms  or  lines  of  [4876e]  ;  in  the  third  column  are 
the  corresponding  terms  of  the  function  [4879/"]  ;  and  the  sum  of  all  of  them  represents  the 
terms  between  the  braces  in  [4879]  : 


[4879o] 


[48796] 


[4879c] 


[4879rf] 


[4879e] 


404 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4880] 


The  terms,* 


'«'4 


m.u 


8}Au= 


-..I3.sïn.(v—v')+lô.s'm.(3v—3v')] 


du 
dv 


[4879/] 


(Col.  a.) 

Function  [4870(/]. 

ce.cos.(2y — 2mv-\-cv)-l[-ce.(l-\-^e^ — Je'2).cos.(2« — 2mv — cv)  1 
+J(3+4w).fe2.cos.(2y-2my)— i(3+4ïK).ce2.cos.(2CT-2«+2«y)  2 
i(;3— 4w).cc2.cos.(2y-2mi')+^(3-4m).cc2.cos.(2cy4-2i;-2/Hw)  3 
— icce' .COS. (2v-2mv-\-cv — c'mv)-^?rcee' .cos. C2v  -'Hmv-  cv — c'mv)  4 
-f-T7Ccc'.cos.(2i'— 2);u'-|-fi'-[-f'mi') — ^'^cc' .cos. {^v  —2mv  —cv-^c'inv)  5 

6 

7 

8 

9 

10 

11 

12 

13 

14 

15 


(Col.  1.) 

(Col.  3. 

A'    [4878]. 

[4876c 

-ce{\+le^-m. 

sin.cz' 

1 
o 

3 

4 

5 

11 

12 

13 

-j-Jce^-sin.2c» 

1 

o 

3 

— ^ce^.s'm.Scv 

.    . 

-{-igf.sin.2gv 

1 
3 

— ^e'y^.s)n.{2gv- 

—cv) 

1 

[4879^] 


[4879fc] 

[4879q 
[48794] 


— |(G-(-15?k).cc3.cos.(2« — 2mv — cu)-j-&c. 
-[-i(6 — 15m).ce^.cos.(2y — 2mv-\-cv)-\-&c. 

-i(3_[_2,„).ej,2.cos.(2y— 2my— 2^v+cd)+&,c. 
-f-ice^.cos  (2eD-j-2u — 2mv) — ice-.cos.(2cu — 2v-{-2?nv) 
— J-(3-j-4»i).fe3.cos.(2y — 2mv-^cv)-\-&L,c. 
-j-J-(3 — im).ce^.cos.{2v — 2mv — c«)-)-&,c. 

.  .  neglected. 
-\-igy~-cos.{2gv-\-2v — 2mv)—lg7-.cos.{2gv — 2v-\-2mv) 
-|-i(3 — im).c}'^.cos.[2v — 2niv — 2gv-\-cv)-\-&,c. 
-|-|e7".cos.(2y — 27iiv — 2gv-\'Cv)-\-&bc. 

Connecting  the  terms  of  this  expression,  we  obtain  the  factors  between  the  braces  in  [4S79], 
neglecting  terms  of  the  tliird  order,  connected  with  the  angle  2v — ■2  m  v-^-cv,  or  with  other 
angles  differing  considerably  from  v.  To  estimate  roughly  one  of  these  neglected  terms,  we 
shall  observe,  that  y^  «  ^  e'  [51 H,  5120]  ;  therefore,  the  greatest  product  of  the  third 
order,  which  can  be  made  of  these  three  quantities,  and  can  occur  in  the  above  function,  is 

ey-;  and,  if  this  be  multiplied  by  the  factor     i^      [4879],  or    its    equivalent    expression 

|m^,  it  becomes  |m^.  ey®.  Substituting  the  values  [.5117,  .5120],  and  multiplying  by  the 
radius  in  seconds  206265",  we  get  ^  m^.  e7^  =  0",38  ;  whidi  represents  the  order  of  the 
greatest  neglected  term  in  [4879].  This  may  be  somewhat  increased  by  integration  in  this 
value  of  u  [4847],  by  means  of  the  divisor  i^ — JV^  ;  for  which  reason  the  author  has 
retained  the  last  term  of  the  function  [4879],  which  depends  on  the  factor  ey~.  We  may 
observe,  that  the  factor  l-|-|e- — f  e'~,  which  occurs  in  the  second  term  of  the  first  line  of 
[4879/],  might  also  be  connected  with  the  first  term  in  that  line. 


*  (2801)     Substituting,  in     Cy)'W^v   [4'754],  the  term  of  [4809],  depending  on  ?A 
[4880a]    it  becomes  as  in  [4880]  ;  neglecting  the  very  small  teim  depending  on   s-.     We  have,  in 


VII.  l.s^6.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  405 

in  the  expression  of     ( '-7^  i.,~-i-)     produce  no  inequality  of  the  third  order     [4881] 
'■  \dv  J  Irirdv 


in  the  integrals. 


Lastly,  we  shall  develop      T~^-f'^'-\     [-4754].     This  function  contains     [4881'] 


dv    u 


'3  m'     y,u'^.dv 


the  following  term,*  — j2~-J^ — i — .sin.  (2îj — 2v').       The    development  of     [1883) 

ft  It 

3m'. U'^  ._  -,    ,,     ^)rl^/^^         •  1  r  3m'. u'^        ■        ,n  ^     ,^ 

___ .  COS.  (2 v-1  V')  [4870] ,  gives  that  of p- - .  sin.  (2 v—2 v'),  [4883] 

by  increasing  the  angle  2*;  by  a  right  angle  [4883rt],  and  multiplying  it  byf     [4883'] 


[4872],  the  expression  of         "  ^.cos.(t) — v')  ;     in  wliich  we  may  change  v  into  t)-|-90'', 
as  in  [48765,  c],  witliout  altering  m  v,    c'mv  ;  and  we  shall  obtain  the  expression  of 

~8Â5:^-""-("~^)-  [4880J] 


This  being  multiplied  by  one  third  part  of  the  expression  [4878],  gives  the  value  of 

-S5-^-^'"-(^-''')-S     [4880].  ^4g,0c] 

Now,  the  chief  term  of  [4872]  has  the  factor     ^.nfi.-,     [5094]  ;  and  that  of  [4878]  is  ce, 

or  c,  nearly,  neglecting  its  sign.      Hence,  the  greatest  coefficient  of  this  product,  is, 

i-.w2.^,.e  =  0,0000004     [5117,5120];  [4680rf] 

which,   in   seconds,   is   less  than    0',09.     This   is  insensible,  and    it    is  not  increased  by 
integration  in  [4847].    The  same  may  be  inferred,  relative  to  the  term  of  [4880],  depending     [4880e] 
on  the  angle    3v — 3v'.      Hence,  we  may  conclude,  that  the  expression  [4880]  maybe 
neglected,  as  in  [4881]. 

*  (2802)     The  first  term   of     (^^)     [4809],  being  substituted  in  [4881'],  produces 

the  expression  [4882]  ;    and  we  have  already  seen,   that  the  expression  [4870]  gives  that  in    [4883a] 
[4876e];  by  changing    2»  into   2i)-f90'',   according  to  the  method  proposed  in  [4876'] 
or  [4883']. 

t  (2803)     Retaining  terms  of  the  third  order  in  [48786],  and  multiplying  by  2,  we  get, 
2 
—  =  2a.\l—{xi+x,,+.r.j)-^xi'i-^2xi  x.^—x^^.  [4884a] 

Substituting  the  values  [48666],  we  obtain, 
VOL.  III.  102 


406 


THEORY  OF  THE  MOON; 


[Méc.  Cél. 


— e.(l — le^ — lf).cos.(cv — ^) 
[4884]  ï^2a.^  +ie^cos.(2ct;  — 2^) 

+  i?2.cos.(2g-?;— 2ô) 

—lef.cos.(2gv—cv—2è-Jr-:s) 

Hence  we  shall  have,* 


[48846] 


[4885a] 
[48856] 


[4885c] 


1  —  {xi-{-x.2-\-X3)  =  1 — c^ — i>^ — c.[l-\-e^).cos.cv  -\-ly^.cos.2gv 

2xxi=  — c.( — 2c^ — i7~)-cos.cv  -rriey^.cos-i^gv — cv) 

— a:j3__  — j,_^     Sga  ).cos.cv. 


The  sum  of  these,  gives  the  terras  between  the  braces  in  [4884a,  4884]. 

*  (2804)     Multiplying  together  the  second  members  of  [4876e,  4884],  we  obtain  the 


expression  of 


3»i'.m'3 


--^  a 


-.sin.f2D — 2v'):  and  the  factor  witliout  the  braces  becomes  3  m  ■—,    as  in 
Ifi.u*  ^  '  a. 


[4885] .  The  products  of  the  terms  between  the  braces,  are  found  in  the  following  table  ; 
in  which  the  first  column  contains  the  terms  of  [4884]  ;  the  second  column,  the  terms  of 
[4876e]  ;  and  the  third  column,  their  respective  products,  reduced  by  [  1 8, 19]  Int.  ;  using 
the  abridged  notation  [4821/]  ; 


(Col.  1.) 

[4884]. 
1 

— f.cos.(;« 


-j-e(ie^+j72)cos.c« 
-j-ie^-cos.2cy 

-}-57®.cos.2^y. 

— Je72.cos.(2jO-y-cD) 


(Col.  a.) 

[487Ge] 

All  the 
terms. 

1 

2 

1 
o 

3 

4 

5 
11 
13 

1 

1 

3 

1 

3 

1 


(Col. 3.) 

_.                 ,.                     .    3m'.«'3   .    ,„       „  ,. 
Correspondinsr  terms  of    -r= .sin.fiJw— at)  ). 

:■  the  whole  function  [4876e]  between  the  braces 

(- 


4^2— i72).sin.(2D— 2»i«) 


1 
2 

-j->(3-|-4;rt).e.(|e24-iy2).sin.(2i'— 2»u'— ft')  3 

-|_|c.(l_}-e2-|-|y2-|e'2).{— sin.(2y— 2mw+cw)-sin.(2K-2»i«-cy)]  4 
-|-i(3-]-4,„).e2.|sin.(2y— 2?nu)— sin.(2cD— 22)+2)rM))}  5 

_f_.(:3_4„j).f2^sin.(2y— 2mw)4-sin.(2cw+2»— 2»iu)}  6 

■\-\ce'.\ — sin.(2u — 2mw+ct) — Cmw) — sin.(2u — 2nîD — cv — drnv)  \  7 
_j_ic(;'.^_|-sin.(2u— 2«u'-j-c2J+c'OTt))+sin.(2« — 1mv—cv-\-c'mv)\  8 

9 
10 
11 
12 
13 
14 
15 
16 


__i_(G+1.5/n+8M2).e3,gin.(2y— 2my— cv) 
— _i^(3-|-2/n).cy2.sin.(2w — 2mu — 1gv-\-cv) 
+(^c3+iey2).sin.(2y— 2/«K— cr        ) 
— ica.sin.(2cw— 2tf+2»!!;)+J:e2.sin.(2cv+2i'— 2m') 
_|(3_4Hi).e3.sin.(2w— 2;ny— cu) 
+^>2sin.(2g'î,-j-2t'— 2mw)— ^y2.sin.(2^y_2t,_j-2»iy) 
_^i^(3_4,n).e72.sin.(2H— 2mw— 2^«+cd) 
— i-cy2.sin.(2i'— 2»!y— 2§-y+cv). 


VlI.i.^G.J    DEVELOP^rENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  407 


-^  n 


(l_}-2e2— |e'2) 


o o 


\m 


.COS.  (2d — 2m2;) 


2.(l+>») 
2— 2/«— c 

2.(1— m) 

2— 2m+c 

7e' 


{1+fe-— i/'— |e'-|.e,cos.(2t)— 2mî?— cî;+ra)  \    2 


e.cos.(2« — 2mv-\-cv — -ji) 


+    oTS o— r.C0S.(2v — 2ot» — c'mV-^-:r!) 

~-{.i — dm)  ^  ^ 


.  COS. (2  V — ^mv^c'mv — si') 

cos.(2v — 2  mv — cv — c'inv^^-\-ui') 
COS.  (2  V  —2  m  t^+c  v — c'm  v — ra+ro) 


2.(2— m) 

7.(2+3  m).ce' 
2.(2— 3ot— c) 

~.(2— 3m).ee' 
'  2^(2— 3  m+c) 
(24-m).ee' 


■?;:;.«      /    ,        ['■-i+m).ee' 
-é.m.~./J^  .A^^^-J^^,cos.(2v—2mv—cv+c'mv+z^—z.') 

(2—m).ee' 

+  "oTo r-T-.cos.(2t) — 2m«+cu+c'mv — •a — îî') 

(10+19/«+8m2)     „ 

■   4:(2^2-+^-^-^°^-C2'^^-2t'+2m.-2.) 

,     (10-19m+Sm.2)     „ 
+  -4:(2^^-^^-'^««-(2-^+2.-2m.-2.) 

—  4:^^24:^  •'''•cos-(2^«-2«+2mt;— 20 

I  (2— m) 

"^  4.(2o-+2-2m)-^^-^"^-^^^"+^^~^^^— ^^) 
17e'3 

+    2. (2 —4m)   •  ^Qs- (2 D— 2 m ?;— 2 c'm v+2z>') 

I  (5+m)  „  / 

4.(2-2m— 2g+c) •  ^ '^  •  cos-(2«— 2mt;— 2g-z;+c^+2a-^)/    15 


The  first  line  of  this  table  includes  the  terms  of  the  function  [4876e],  and  by  adding  them  to 
...  ,,  ,  3m'  «3  [4885rfl 

theremammg  terms  of  [4885c],  we  get  the  terms  of  —-^.sm.(^v—2v')  ;  which  ought  to  be 


408 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél 


The  terms  of  this  formula,  depending  on  the  angles  2cv — 2v-T-2mv — 2ra  and 
[4886]  2gv — 2v-{-2mv — 2^,  have  divisors  of  the  order  m  ;  and  they  again  acquire 
these  divisors,  by  integration,  in  the  expression  of  tlie  moon's  mean 
longitude  ;  wliich  reduces  them  to  the  second  order  ;  and  this,  it  would 
seem,  ought  to  make  the  inequalities  relative  to  these  angles  become  great. 
But  we  must  observe,  that,  by  [4853,  &ic.],  the  terms  having  for  a  divisor 
the  square  of  the  coefficient  of  v,  in  these  angles,  nearly  destroy  each  other, 
in  the  expression  of  the  mean  longitude  ;  so,  that  the  inequalities  in 
question,  become  of  the  third  order,  conformably  to  the  result  of  observations, 
as  will  be  seen  hereafter  [5576].  We  may,  therefore,  for  this  reason,  dispense 
[4887]      with  the  calculation  of  the  terms  multiplied  by    e* 


[4886'] 


[4886"] 


„9    9 

e  7  , 


because  the 


[4885e] 

[4885/] 

[4885g] 
[4885A] 

[4885;] 
[4885fc] 


[4885i] 


equal  to  the  differential  of  [4885]  divided  by  — dv  ;  or,  in  other  words,  it  ought  to  be  equal 
to  the  terms  between  the  braces  in  [4885],  changing  cos.  into  sin.,  and  neglecting  the 
divisors  2 — 2m,  2 — 2m — c,  he,  which  are  introduced  in  [4885],  by  the  integration.  The 
comparison  of  the  sums  of  the  terms  of  [4876e,  4885c],  with  those  of  [4885],  may  be  made, 
in  most  cases,  by  inspection,  or  by  very  slight  reductions  ;  and  they  will  be  found  to  agree, 
neglecting  some  terms  of  the  third  order,  depending  on  angles  which  are  not  expressly 
included  in  [4885]  ;  or,  on  angles,  whose  coefficients  are  not  much  Increased  by  integration  ; 
as  2v — 2mv-{-cv,  2v — 2)nv-\-c'mv,  he.  The  reductions, relative  to  the  terms  depending 
on  the  angle  2v — 27nv — cv,  are  rather  more  complicated  than  the  others,  on  account  of  the 
great  number  of  its  terms.  We  have,  therefore,  placed  these  terms  in  the  following  table 
[4885/],  in  the  order  in  which  they  occur  in  the  functions  [4876e,4835[]  ;  and  have  found 
their  sum  in  [4885?n].     Comparing  this  sum  with  the  corresponding  coefficient 


— 2.(1+ÎH,),(1+Î< 


-h7'- 


\e^).e, 


in  the  second  line  of  [4885],  we  find  that  they  nearly  agree  ;  their  difference  being  equal  to 
the  very  small  quantity  2me.^^e~,  which  maybe  considered  as  of  the  fifth  order  ;  and, 
as  this  is  to  be  multiplied  by  the  factor  without  the  braces,  which  is  of  the  order  nfi,  or  of 
the  second  order,  it  becomes  of  the  seventh  order,  which  is  usually  neglected  in  this 
coefficient  : 

— 2e.(5+,»5e2  _.|e'2)— 2me.(l+Je2  — |e'2) 


[4876e],line2 

[4885c],  line  3 

4 

9 

11 

13 


-2e.{—i,e"—i,y^ 

— 2e.a+ite2+A7^. 

—2e.{+,%e^ 

— 2e.(-,\e^— A7=^ 

— 2e. 


)—2me.{  —I  «2—172 
c'-2) 

)— 2me.(  +I^e2 

) 

)— 2me.(  — i1;e2 


) 


)• 


[48S5m] 


Sum  is     =-2e.(l  +  ie^-i?^-|e'2)-2me.n+jJe^-|7--ie'-). 


VII.i.§6.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  409 

quantities  of  the  fourth  order,  which  result,  after  integration,  nearly  destroy 
each  other. 


The  intes;ral     tt^-TI       ]-'^      [4754],    contains    also    the     following 

°  h-  -^    \  dv  J      ir 


[4887'] 


term,* 


-T-/-^;^-Si»-(^'— ^')-  [4888] 


4  II 
This  quantity,  by  development,  produces  the  following  expression,! 


*  (2805)     The  second  term  of  (—]   [4809],  namely, — ^  .  sin.  (tJ — v'),     being 

,  .   ,.    ,   ,  2,fo  ,  .         2       /dq\     dv       .  3m'  u't.dv    .     ,         ,. 

multiplied  by       — ,,     produces,  m     "^^i"  •  (^^^j    ,7>    t^e  term,  —  —  .-^.sm.(«— 1>  )  ;     [4887a] 

whose  integral  is  as  in  [4888]. 

t  (2806)     We  may   change    v  into    v-\-^(f,    in   [4872],  in   the  parts  which  are  not 
connected  with   m^v,  or  c'mu,  upon  the  same  principles  as  in  [4876a,  &c.].    By  this  means,     Mggg^n 
the  expression  [4872],  with  the  addition  of  tlie  two  terms  [4870.c],  becomes  as  in  [48896]. 
Multiplying  [4884]    by  ^,  we  get  [4889c]  ;    always  using  the  abridged  notation  [4821/],    ..gg 
which  ivill  frequently  be  done,  in  the  commentary  oil  this    hooJc,  without  any  particular 
notice,  that  the  angles  -a,  •s/,  ê,  are  omitted; 

_2  r{l-\-<2e^-\-2e"^).sm.{v—mv) 

9)ii'.  «'■*    .  9  nt     rt         )  .  \      ^       •     /       1  \ 

— ^-p, — r.sm.ti; — V  )^ — ; — .  —  .  <     +2e.sm.(cu — v-\-mv) — 2e.sm.[cv-\-v — mv)       ,   ,  ^.  „„, 

87i2.«4  ^  ''  8a,     a'      \       '  '^  '        ^  ^     ^  C  [4889i] 

'  (_     -j-e'.3in.(y — mv-\-c'mv)-\-3e'.sm.{v — mv — c'mv)  , 

3-==  3  «  •  Î  (1-*  e2_i7.2)_e.cos.c .+  &c.  S .  ^^ggg^^ 

The  product  of  these  two  expressions,  retaining  terms  of  the  same  form  and  order  as  in 
[4889],  becomes  as  in  [4889A].     For  the  product  of  the  two  factors  without  the  braces,  is 

evidently  equal  to    —  •-•  -,     as  in  [4S89A].     We  shall  now  multiply  the  terms  between     [4889rf] 

the  braces  in  [48895],  by  those  in  [4889c].  The  first  line  of  [48895],  being  multiplied  by 
the  factor     (1 — 56^ — iy^)     [4889c],  produces  the  expression, 

{\  +  le^—lf-+2e'^).sm.{v-mv)  ;  ^^^^^^^ 

and  the  term  — c.coscd  [4869c],  being  multiplied  by  each  of  the  terms  depending  on  e, 
in  the  second  line  of  [48895],  produces  a  term  of  the  form  e-.sin.(y— mi')  ;  adding  these 
two  terms  to  those  in  [4889c],  we  get, 

{l  +  ie^-iy^+2e'^).sm.{v-mv),     as  in  [4889A].  ^^gg^^^ 

VOL.  III.  103 


410  THEORY  OF  THE  MOON;  [Méc.  Cél. 


2  I  I— m 


.cos.(w  —  mv)     \    1 
.  ,  .u„..,^      „  , .  '     -\-p'.r.nfi.Cv — «?? 


[4889]     — — .r — —.sin.ft; — w)= — .-.-,.(    +e.cos.(« — mt-+c'mw — -')        ^-  2 


[4890] 


[4891] 


3  ft'  \ 

-4 .cos.fi' — mv — c'mv-X--J)  j    3 

the  other  terms  of  the  integral  [4887']  may,  in  this  part,  be  neglected.    This 
being  premised,  if  we  observe,  that  the  expression  of  u  [4826]  gives,* 

l+e"+l/  \  1 

^'1,,  _i)    +(1— c-).e.cos.cî)— ^)  .  2 

a    )  g  I 

the  term     ( -^  +  m  )  •  y-a'/f -y^)  • '"i  ?       of    the    equation     [4754],    will 
produce,  by  its  development,! 


Lastly,  the  first  term,  or  unity  [4889c],  being  multiplied  by  the  terms  in  the  third  line  of 
[4889i],  produces  those  depending  on  e',  in  [4889A]  ; 

r{l+le'^—ly^-}-2e'~).sm.{v—mv)] 
3m'  u'i  -  a    a      y  ,    .     .  ,  ,      ' 

[4889A]  ~\}fi-^'^^'''^^"~'^'^~^'''^^"^''^"\      +  c-sin.(t!— ?w«)-j-cw«— n) 

\      -\-Ze!  .%\\\.{y — mv — c'mi;-(- si') 

Multiplying  this  by  ih,  integrating,  and  putting  in  the  divisors  c'=l,  it  becomes  as  in 
[4889i]      [4889].     We  may  remark,  that  the  term    — §7^,  which  we  have  connected  with  the  factor 

(l-|-o<^^2_|_2g/2j^  i„  [4870^',  4872],  ought  also  to  be  connected  with  that  in  [4889/i,  4889]  ; 
'■^^^^^^     so  that,  instead  of    l+Je^—i  5.24.2 e' 2,   we  may  write     l+J t^— J-i^2_|_2e/a_ 


*  (2807)     The  second  differential  of  u  [4826],  taken  relatively  to  d,  and  divided  by 
dv^,  gives, 

[4890a]  ''^'^^=^.l-r^e.(l+.s).cos.(c.-.)  +  ^V-cos.(2,o-.-2ô)r 

Adding   this   to  the  expression  [4826],  and  neglecting  terms  of  the  fifth  order   (1 — <?).^ 
[48906]     [43O8e],weget[4890]. 

t  (2808)     The  terms  of  the  integral     yJr/;^-^'      are  contained    in    [4885,4889]. 
[4892a]     These  two  functions  must  be  multiplied  by  the  expression  of     ——-\-u     [4890];    and    the 


Vll.i.^se.]    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  411 


ddii  \      2      ^f/Q    dv 


dv 


Ifi  '-^    dv  '  «3 

(l4-3ea+j-v3— ge'a) 
2— 2m 


.cos.{2v—2mv) 


^H(l— "0       2-2m-c    V    T^*  2     >'\  ^  '     ^ 

2(1 — m)  /r»         rt         . 
'^ -.e.cos.(2îJ — 2'mv-{-cv — ra) 

—  :^~7^ — K  •  COS. (2  V — 2mv-\-c'mv — -a') 

2.(2 — m) 

\  —  „  ,!l'^ —.eé.cos.(2v — 2 mv — cv — c'mtj+ra+ra') 

\        2.(2— 3  m — c)  ^  '       '      / 

'  o  '/7^~^ — r~: •  ^ ^'- COS. (2 v  —2 m «4-<^ « — c'm v — ro+w) 

2.(2 — Jot-j-c)  ^  ' 

,  (2+ot)  , 

+   -^5 -.ee.cos.(2» — 2m« — cv-\-c'mv-{--a — ra') 

/*.  {  Ài Tïl C) 

.           (2-m) 
2    /+  ITTTi — t--^^-cos.(2î; — 2'mv-{-cv-\-c'mv — tx — n') 

"'    \-   4:(2^2+2^-^'-^°«-(2c.-2.+2m.-2.) 

+  X(2^2=:2;^-^-'^''^-(^^^'+^^— 2»^^— 2^") 

+   ^-6:(ï=^3  -i:(^qk)5-^""-^«^-C2â-.-2«+2m«-20 

c  (4^2 — 1)  /2 m)         ) 

+   Jï6:n=7,ô"^  4.(2^^+2-2,«)]  •'''•cos.(2^«+2i'-2mv-20 

Ij  (5-j-m)  3.(1— m)  )       ^ 

"U.(2-2«-2^+7)+4(2:^^5-''"-^°^-(2^~2mi;-2gt;+ci;+2«-^) 
+   — rfi T— .-.cos.(zj — mt)) 

4.(1 — m)        a  ^  ■' 

+  J- .  —  .e'. cos.(t' — mv+c'7nv — ^') 


\^ 


3 


4.(1— 2/«) 


-.  e'.cos.(w — mi' — c'mt;+ra') 


[4892] 


18 


sum  of  the  products  will  be  equal  to  the  function  [4892].     In  finding  the  products   of  the 


[4892a'] 


412 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4893] 
[4894] 


7.     The  term 


>.(l+,sjl' 


of  the  expression 


_1  f'^3\__L  f'R 


h~      \  du  J         h^ 


ds 


[4808], 


[  48926] 

[4892c]     _  __     [4889],  which  is  of  the ybwr^A  order  ;  by  this  means,  these  terms  become  so  small, 


functions  [4889,4890],  we  may  neglect  the  second  and  third  lines  of  [4890]  ;  for  (1 — c^).e 
is  of  the  third  order,  7®  is  of  the  second  order  ;  and  these  are  to  be  multiplied  by  the  factor 


2  a 


[4892rf] 
[4892e] 


[4892/] 


[4892g:] 


that  they  may  be  neglected,  and  the  function  [4890]  is  reduced  to  its  first  term 
-.(l+e^-j-iy^).  MultijDlying  this  by  the  terms  in  [4889],  lines  1,2,3,  we  obtain  respectively 
the  terms  in  [4892],  lines  16, 17, 18.  In  the  term  depending  on  cos.(j; — mv),  in  line  16.  we 
may,  for  greater  accuracy,  decrease  the  factor   l-|-|e"+2c'^,  by  |>^,  as  in  [4889i]. 

We  shall  now  compute  the  product  of  the  functions  [488.5,  4890].     In  the  first  place,  the 
product  of  the  factors,  without  the  braces,  is 

2 

3  wf .  ^  X  -  =  —  ;     as  in  [4892]. 
a,      a  a, 

The  multiplication  of  the  factors,  between  the  braces,  is  made,  term  by  term,  as  in  the 
following  table  ;  in  which,  the  first  column  contains  the  terms  of  [4890] ,  the  second  column 
the  terms  of  [4885],  and  the  third  column  the  corresponding  products  of  the  terms  between 
the  braces,  in  these  lines  of  the  two  functions  respectively:  observing, that  4^^ — 1^3,  nearly: 


[4892^1] 


(Col.  1.) 

Terms  of  [4890]. 
1 


(1 — c').e.cos.cv 


(4g^-l)    2 


.y^.C0S.2^D 


(Col.  2.) 

Terms  of  [4885]. 
whole  of  [4885] 
1 

2 

1 

1 

3 


(Col.  3.) 

Products  of  these  terms. 


whole  function  [4885]  between  the  braces 
.cos.(2î) — 2mv) 


2— 2nt 
2.(l-}-jrt) 


2-2m-c 


•{e^-\-i')'^)-e.cos.(2v — 2m  v — cv) 


(1— cS) 

■-TTz --.e.coa.C^v — 2  mi' — C1O+&C. 

4.(1 — m)  ^  '  ' 


1 

2 
3 
4 


^y  ^^ .;  2.  {cos.(2^i)-2y+2)«D)+cos.(2^f+2r-2mî))  \ 5 


— — .c>^.cos.(2d — 2wv — 'i. g  v-\-cv)-\- hx..        6 


4.(2— 2wi+f) 


Connecting  the  terms  from  lines  2  to  6  of  this  table,  with  those  in  line  1,  or  the  lines  between 
the  braces  of  [4835]  ;  we  get  the  corresponding  terms  between  the  braces,  of  the  function 
[4892]. 


VII.  i.  §7.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  413 

becomes,  by  neglecting  quantities  of  the  fourth  order,* 

a.     (  4  )  h~ 


|3"  being  a  function  of  the  fourth  dimension  in  e,  y  ;  and  6s  the  part  of  s 
arising  from  the  disturbing  force.  We  shall  see,  in  [5596],  that  ^5  is  of  the 
following  form  ;t 


[4895] 
[4896] 


[48936] 


*  (2809)  Developing  the  expression  [4893],  according  to  the  powers  of  s,  it  becomes 
— /i~-.(l — J«^+-r«'* — Sic).  If  we  substitute  in  this  the  value  of  5  [4818],  augmented  by  [4893a] 
the  term  ôs,  and  neglect  terms  of  the  order  ôs^,  which  are  noticed  in  [4958,  &;c.],  we 
shall  find,  that  the  part  of  the  function  [4893],  depending  on  Ss,  is  equal  to  the  differential 
of  the  expression  [4893«],  relative  to  S,  which  is  — Jr^.{-3sSs~\-J^-s^Ss-&Lc.).  Neglecting 
terms  of  the  order  s^5s,  it  becomes  3h~^.sSs,  as  in  the  last  terra  of  [4895].  Now,  the 
value  of  s  [4818]  gives,  by  means  of  [1,  3]  Int., 

l—^s^={l—iy^)+if.cos.2gv;  -'^s^  =  M7^— i|7^cos.25-ô+&c.;  [4893c] 

1— §s^+W— &ic.=  {l—t/-)+Î7^-{l—i7^)-cos.2gv-\-teTms  of  the  4th  order.  [4S93rf] 
And,  from   h^  [4863] ,  we  get, 

—  ^-2.  =: .^i_|_e2-]-y2^_j_ terms  of  the  4th  order}.  [4893el 

Multiplying  together  the  two  expressions  [4893£/,e],  we  get  the  part  of  the  function  [4893a], 
which  is  independent  of  Ss,  as  in  [4895]. 

f  (2810)     The   form   here  assumed  for  5s  is   easily  obtained  from  a  comparison  of  the 
equations  [4754,  475-5],  by  which  u,  s,  are  determined,  with  the  preceding  development  of    [^^'''"J 

the  terms  of  M.  Forthe  equation  [4754]  contains  the  function  — r3[~r  )  — rô^-(  T  )'  whose     [48976] 

terms  have  been  developed  in  [4866, 4870, 4872,  &tc.]  ;  and  the  equation  [4755],  by  which 

s  IS  determined,  cont3.\ns  the  same  function,  multiplied  by    -.        Now,    the    chief  term  of    r4897ci 

the  factor      -     is  equal  to    a-,.sm.{gv — ê),     as  is  evident  from  [4818, 4791]  ;  and,  if  we 

multiply  the  terms  we  have  just  mentioned  [48G6,  4870,  4872,  fee]  by  a7.sin.(o-j) — ê),  we  [4897rf] 
shall  obtain  the  most  important  terms  of  [4755],  depending  on  the  function  [4897c].  Thus, 
the  first  term  of  [4866]  produces  a  term  depending  on  sm.(gv—ê),  which  may  be 
considered  as  being  included  in  the  form  [4818].  The  second  term  of  [4866]  produces  the  '■  ^' 
angles  gvzhcv  [4897],  lines  3,  4.  The  third  term  of  [4866]  produces  the  angles 
gv±(fmv  [4897],  lines  8, 9.  The  first  term  of  [4370]  produces  the  angles  2v — 2mvzizgv 
[4897],  lines  1,2.  The  second  term  of  [4870]  produces  the  angles  2v — 2mvdizgv — cv 
[4897],  lines  6, 7.     The  third  line  of  [4870]  produces  the  fifth  line  of  [4897]  ;  and  so  on,     [4897^] 

VOL.  III.  104 


414  THEORY  OF  THE  MOON  ;  [Méc.  Cél 

6s=^  B^^^K J'. sin. (2 V— 2m V— g v+ô)  1 

-i-B^^'\y.s'm.(2v — 2mv+gv—ê) 
+  B^^-^ .  e  -/.sin.  {gv-\-cv — ê — ct) 
-j-  B^'-^\  ey  .sin.Çgv — cv — ^+^) 
-{-B^^''\ey.sin.(2v — 2mv — gv~\-cv-^Ê — to) 
~i-B^'-^\er.s'm.(2v — 2mv+gv — cv — ^+ra) 
-\-B^^'^\ej.sin.(2v — 2mv—gv — ct)+â+ra) 
-{-B^'-''\e'-)'.s'm.(gv-\-c'mv — ê — z=') 

+B^^^Ke'r.sm.(gv — c'mv — ^+ra')  9 

-\-Bf\  eV-sin.(2« — 2mv—gv-i-c'mvi-ê — ra)  10 

+B[^''Ke'y.s'm.(2v — 2mv—gv—c'mv-\-É-{-^') 
+Bl''\e"-y.sm.(2cv—gv—2zi+è) 


Atisumed 
form  of 


2 
3 

4 
5 

3+^)  6 

7 
8 


')  11 

12 


16 


+Bl''\e"-y.sm.(2cv—gv—2zi+è) 

+  B\'^Ke^y.sïn.(2v—2mv—2cv+gv+2r,—D)  13 

+B<'-^Ke''y.s\n.(2cv+gv—2v+2mv—2^—è)  14 

+5^''''.-.7.sin.(^ti — v+mv — ê)  15 

+  5''^^.-,.7.sin.('£-«+î? — mv — ^). 
a  ^^ 

for  other  terms.     Hence  we  see,  that  the  forms  of  the  angles  in  [4897],  are  given  a  priori 

[4897ft]    by  the  theory;    and  they  agree  with  the  results  of  observation   [5596].     The  differential 

equation  in    s  [4755],  is  similar  to  that  of  u   [4754],  and  may  be   reduced  to  the  form 

[4897m],  which  is  similar  to  [4845].     For  the  chief  term  of  s  is  given  in  [4818],  and  if  we 

[4897i]    suppose  the  other  terms  of  «  to  be  represented  by    5s,  we  shall  have  «=7.sin.(^i' — â)+i3s. 

dds  d-.Ss 

Its  difFerential  gives      "7^= — g^.y.sin.(gv — ^)-\-~pr-       Multiplying  the  fu'st    of    these 

[4897A]    expressions  by  g--.  and  adding  it  to  the  second,  we  get    -—-\-g^.s=-—-j~g^.5s;      and    if 
[4897t]     we  put  the  second  member  of  this  expression  equal  to   — n',  we  shall  get, 

[4897m]  ^^+^9.,  +  n'=0. 

This  is  of  the  same  form  as  [4845] ,  g  taking  the  place  of  JV,  and  differing  from  unity  by 
quantities  of  the  order  m^  [4828c,  4845'].  Moreover,  n'  may  be  considered  as  a  series  of 
terms,  whose  general  form  is  k'.sm.{iv — 6),  like  that  in  [4846]  ;  and  the  part  of  s,  relative 
to  this  sine,  is  represented  as  in  [4847,  Sic]  by 


VII.  i-sW]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  m. 


415 


The  number  placed  beloio  any  one  of  the  letters  B,  indicates  the  order  of  that 

letter.     Thus,  Bf  is   of  the  second  order  ;  ^t"'  is  of  the  first  order  ;    and      t'*^^^! 

B'-g'^  is  finite.     We  may  observe,  that  this  takes  phice  according  as  the  number     [4898'] 

by  wliich  v  is  multiplied,  in  the  corresponding  sine,  differs  from  unity,  by  a 

finite  number,  by  a  quantity  of  the  order  m,  or  by  a  quantity  of  the  order  nf,      [4899] 

respectively  ;  because  the  integration  [4897o]  causes  the  terms  to  acquire  a     [4900] 

divisor  of  the  same  order.     This  being  premised,  we  shall  have,* 


-JV2 


.  sin.  {iv — 6)  ; 


so  that  these  terms  may  be  much  increased  by  this  integration,  when  i  is  nearly  equal  to 
unity.     From  the  similarity  of  the  equations  [4754,  4755]  it  is  evident,  that  the  terms  of  n' 

_2 

[4897m],  depending  on  the  disturbing  force  of  the  sun,  must  have  the  same  factor      m  ,     as 

the  functions  [4866, 4870, 4872,  &c.]  ;  and  in  is  of  the  order  «i^  [5094],  or  of  the 
second  order.  This  factor  is  divided  by  i^ — JV~,  in  finding  the  value  of  s  [4897o],  or  that 
of  &s  [4897]  ;  and,  as  i^ — JV^  may  be  considered  as  of  the  same  order  as  i~^g'^^i^-\-^m^ 


[4828e]  ;    the  order  of  the  symbol  B  will  ie  represented  by 


Hence,  it 


i2— 1— 3m2 

appears,  that  if  {  differs  considerably  from  unity,  tlie  corresponding  symbol  B  will  be  of  the 
second  order,  as  in  [4897],  lines  2,  3,  4,  5,  Sic.  ;  using  the  values  of  c,  g  [4828e].  In  the 
first  term  of  [4897],  the  coefEcient  of  u  is  i=2 — 2m — g^=l — 2m  nearly;  hence, 
i^ — 1 — I'm^  is.  of  the  order  m,  and  the  corresponding  value  of  B  [4897r]  is  of  the  order 
m,  represented  by  Bf;  and  the  same  occurs  in  lines  8 — 11  [4897].  In  line  12  we  have, 
i=^2c—g  =  1  —  if'-rri^  [4828e]  ;  hence,  the  divisor  of  the  expression  [4897 r]  becomes  of 
the  order  m^,  and  the  corresponding  value  of  B  is  reduced  to  the  order  m",  or  a  finite  order, 
as  it  is  called  by  the  author  in  [4898'],  and  is  represented  by  i?},'".  If  we  compare  the 
indices  of  B  [4897],  with  their  values,  computed  in  [5122—5214],  we  shall  find  they 
generally  agree  ;  but  the  term  B'i^'  [5179]  is  nearly  oï  the  first,  instead  of  the  second 
order  ;  i?i'-'  is  of  the  second  order,  fee. 

*  (2811)  Substituting  in  the  firstmember  of  [4901],  the  values  of  A-s,  s  [4893e,4897i], 
and  neglecting  terms  of  the  order  &^  we  get  [4901a].  If  we  also  neglect  terms  of  the  fifth 
order,  it  becomes  as  in  [4901e]  ; 

3s.6s         3      ,     .     ^ 

—  =  -•7<^*-sin.(^r— â)x  |l+e^+/2+terms  of  the  fourth  order} 

=  -.Yh.sm.{gv—è). 

We  must  substitute  in  this  last  expression,  the  value  of  vs  [4897],  and  we  shall  get  [4901]. 
If  any  term  of  &  be  represented  by    C.sin.F,   the  two  corresponding   terms  of  [49016] 


[4897o] 

[4897p] 
[4897?] 

[4897r] 

[4897s] 
[4897<] 
[4897u] 


[4901a] 
[4901i] 
[4901e] 


416  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

^==-~l  Bf  -B^^  ]  .y^cos.(2  v-2  m  v)  1 

+  ^.B^p.7~.cos.(2v—2mv—2gv-\-2è)  2 

—  --.Bf\e  y^cos.r2  &■  v—c  v—2  é+^)  4 
2a,                          ^ 

+  -.B^,'Key^cos.(2v—2mv—2gv+cv-^2ê—^)  5 

[4901]                                  -i- ~AB^'^—B'i'>l.ef-.cos.(2v—2mv—cv+^)  6 

+  ^.lB[-^+B['^.e'7''.cos.(c'mv—^)  7 

—  — .£f'.e'7^cos.(2  ?;— 2  m  v+c'm  v—z,')  8 

^.S'"').e'7^.cos.(2 1>— 2  m  v—c' m  v+^')  9 

2a, 

—  —.B^^'\e^y^.cos.(2cv—2  ^)  10 

+  —SB'-}*^+B^!'^.-.7^cos.(v—m  v).  11 
2a,        "^            "a. 


will  be 
[4901(i]  ^.y.C.cos.{(^D— â)«>F|  —^.y.C.cos.^^t)— â+F^  ; 

but  it  is  not,  in  general,  found  to  be  necessary  to  notice  more  than  one  of  these  terms.  The 
[4901c]  only  cases  in  which  the  author  has  noticed  both  terms,  are  those  depending  on  Bf\  Bf* 
[4897],  lines  1 — 4.  The  neglected  terms  are  generally  smaller  than  those  which  are 
retained,  or  they  are  such  as  depend  on  angles  that  have  not  been  usually  noticed,  because 
their  coefficients  do  not  increase  by  the  integrations.  For,  the  function  [4901]  forms  part  of 
r490in  ^^^  expression  of  n  [4902,  or  4845]  ;  and  its  coefficients  may  be  increased  by  the  divisor 
t2 — JV^  [4847,  8iC.],  when  i  differs  but  little  from  unity  ;  as  is  the  case  in  lines  3 — 6,11 
[4901].  To  estimate  roughly  the  order  of  the  terms,  which  are  not  increased  by  the 
integrations,  and  are   neglected  as  in  [4901],  we  may  observe,  that  they  produce  terms  of  a 

[4901g]    similar  order  in  u  [4847],  and  in  the  lunar  parallax  [5309,  &.c.].     Now,  if  we  put  -   equal 


VII.  i.'^^  T.]    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  417 

If  we  connect  together  the  different  terms  which  we  have   developed,   we 
shall  find,  that  the  equation  [4754]  becomes  of  the  following  form,* 

cJc/u 
0  =  "IP  +  "  +  "  ;  [4902] 

n  being  a  rational  and  integral  function  of  constant  quantities,  and  of  sines 

and  cosines  of  angles  proportional  to  v  ;  but,  as  loe  propose  to  notice  all  the     [-1903] 


to  the  constant  term  of  the  lunar  parallax  3424', 16  [5331],  and  use  the  values  of  c,  e',  7 


[5194,5117],    also 


f^u   [5221],  we  shall  get,  very  nearly, 


_3 
2  a, 


:40' 


TTZ-n-' 


:2%3;       :^.e'Y' 


0%7: 


— -    e^  y~  :=  0'  1  •         — -  .  -    >2 


2  a. 


2  a,    a' 


OM. 


The  first  of  these  expressions,  being  multiplied  by  the  very  small  quantity  .Bf,')  [5177], 
becomes  insensible;  and  it  is  retained  in  [4901]  line  1,  merely  because  there  is  no 
inconvenience  in  doing  it,  since  it  is  found  necessary  to  notice  the  angle  2d — 2mv,  in 
consequence  of  the  magnitude  of  the  other  term   i?J'\     In  like  manner,  the  term 


-^  .e>=2.^|'=— 0',01 

2o, 


[5178, 490  U], 


[490U] 


[4901i] 


is  nearly  insensible  ;  but  it  is  retained  in  [4801]  line  3,  because  the  coefficient  c,  in  the 

angle     cv — -us,    diflers  but  very  little  from  unity  [4828e],  and  it  is  increased  by  integration  ; 

which  is  not  the  case  with  the  coefficient  depending  on  the  other  angle    2gv-\-cv — 2d — ra, 

with  which  -B^-'   is  connected.      One  of  the  largest  of  the  values  o{  B,  is  that  denoted  by 

3 
J?f>  =  0,07824    [5183];     multiplying  it  by  the  coefficient     —  .e'j2  =  0',7,     with  which    [4901A] 

it  is  connected  in  [4901]  line  7,  it  becomes  0',05  ;  this  is  retained  in  the  angle  c'mv — ■n' 
[4901]  line  7,  because  the  divisor  i- — N^  [4847]  is  nearly  equal  to  unity  ;  but  it  is 
neglected  in  the  angle  2gv-\-c'mv — 2d — ra' ;  because  it  is  considerably  decreased  by  the 
divisor  i- — JV^,  which  is  nearly  equal  to  3.  We  may  also  observe,  that  it  is  of  more  importance 
10  retain  the  terms  depending  on  the  angle  c'mv — -a,  than  those  on  2gv-\-c'mv — 2d — -sj' ; 
because  the  terms  introduced  by  the  former,  in  the  value  of  dt  [4753],  are  increased  by 
integration,  in  finding  the  value  of  t,  in  consequence  of  the  smallnessof  the  coefficient  c'm 
of  the  angle  v.  Similar  remarks  may  be  made  relative  to  the  other  terms,  which  are 
neglected  or  retained. 


[490K] 


[4901»; 


*  (2812)      Connecting  together  the  terms   [4866,4870,4872,4892,4895,4901,  &c.], 
depending  on    Q,  and  putting  the  sum  equal  to  n;  then  adding  it  to  the  terms  of  [4754],    [4909o] 
which  are  independent  of  Q,  it  becomes  as  in  [4902]. 


VOL.   III. 


105 


418                                              THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

inequalities  of  the  third  order,  and  the  quantities  of  the  fourth  order  connected 
[4903']     with  them,  ive  must  add  to  the  preceding  terms  all  those  which  depend  on  the 
square  of  the  disturbing  force,   and  become  of  these  orders  by  integrations. 
We  shall  now  examine  these  new  terms. 

r4<»03"i         ^'     ■^°^'  *^"^  purpose  xve  shall  suppose  ou  to  be  the  part  of  u  arising  from 
the  disturbing  force  ;  and,  that  we  have,* 

aàu  =  AJ-^K  COS. (2» — 2  mv)  1 

+  J/^'.  e  .  COS.  (2  w— 2  m  v—c  v+^n)  2 

+A^'-^\e.cos.{2v — 2mv-\-cv — ra)  3 

+^/'.  e'.  COS. (2  V — 2  m  v-{-c'mv — ^')  4 

Assumed                                                             ^  ,,-,        ,                  ,^             ^                     *            .       /x  r 

form  of                               +  J,<  ^  e.  COS. (2  V — 2  m  v — cmv-\-^)  o 

ÔU.  ~  \ 

-^A^'-^le'.  cos.(c'mv — W)  6 

-|-^/'^'.  e  e'.cos.  (2  v — 2  m  v—c  v+c'm  ?;+« — -')  7 

+^/''.ee'.cos.(2  «; — 2  m  v — cv — c'mtJ+ro+za')  8 

+^i''*^e  e'.cos.  (c  v-^-c'mv — « — t^')  9 

+yi/^'.ee'.cos.(cD — c'mv — -zs+ijj')  10 

[4904]                               +4'°).  e^cos.(2ct;— 2^)  11 

+4'^'.  C-.  cos.(2cv—2v-i-2mv—2^)  12 

+4'->.  '/.  cos.(2  o-v— 2  Ù)  13 

+4'='.7^  cos.(2^«— 2«+2ot«— 20)  14 

+4»'.  e'^cos.(2  c'mi)— 2  ^)  15 

+4'^'.e7^cos.(2o-i)— CÎ)— 20+ra)  16 

+4'«.e7^cos.(2j;— 2mw— 2^î)+cv+2â— T.)  17 

+^["'.  -.cos.(î; — mv)  18 


+4^'-  -.e'.cos.(« — tnv-\-c'mv — -n')  19 

a 

+4°). -,. e'.cos. (î; — m^; — c'miJ+ts')  20 


a 


[4904a]      *  (2813)     The  terms  of  a<5tt  [4904]  are  evidently  of  the  same  form  as  those  of  tlie  function 


Vll.i.  §S.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  419 

The  number  0,   1,  or  2,  placed  below  any  one   of  the   letters   A,  denotes, 

that  it  is  of  the  order  zero,  or  of  the  order  m,  or  of  the  order  m^,  respectively.      [4905] 

We   shall  here  take  into  consideration  the  inequalities  of  the  third  order,  and 

those  of  the  fourth  order,  which  can  produce  terms  of  the  fourth  order   in 

the  coefficients  of  the  inerjualities  of  the  third  order.     We  shall  continue  the 

approximation  to  a  greater   degree  of  accuracy,    relative   to   the  inequality     [4906] 

depending  on     cos.(j' — mv).      This  being  premised,  we  find,  that  the  term 

*"'  "'^  ,  .  ,3ot'  u^  (5m 

[4865']  gives,  by  its  variation,  the  expression ^~T~  ?      f^""'^      [4907] 


[4905'] 


which  we  deduce  the  following  function  ;* 


n  [4902a].     Tlie  order  of  the  coefficient  A  may  be  found  by  the  formula 


ia— l-f3ma    '      [49046] 

whicli  is  similar  to  that  in  [4S97/-],  using  for  JV~  the  value  of  c-=l — Zm",  instead  of  g^, 
which  is  used  in  [4897 5-,  r]  ;  i  being  the  coefficient  of  v,  in  the  angle  corresponding  to  the  [4904cl 
coefficient.^.  Thus,  for  «/if"'  [4904],  we  have  i  =  2— 2/«;  hence  ^<">  is  of  the  order  m^, 
or  2.  For  A'^^,  we  have  i  =  2 — 2  m — c=l — m,  nearly;  hence  ^^'^  is  of  the  order  m, 
or  1;  and  so  on,  for  the  other  coefficients  of  [4904].  If  we  compare  these  indices  of  A, 
with  the  values  obtained  by  numerical  calculation  in  [5122 — 5213],  we  shall  find,  that  in  [4904rf] 
general  they  are  correctly  marked. 

*  (2314)     The  expression  [4907],  whose  value  is  to  be  determined,  may  be  put  under 
the  form 

3      2     m'.  m'3 
~Ya^7r'i}fi.u^^"'  "'  [4908a] 

in  which  the  second  and  third  factors  have  been  already  computed  in  [4884, 4866]  ;  we  shall 

3 

first  find  the  product  of  these  two  factors,  and  then  multiply  it  by and    a  Su.      Now, 

if  we  multiply  the  factors  without  the  braces,  in  [4884j  4866],  by ,       the    product 

becomes 


2  _a 

m    ^3^  3  m 


as  in  the  second  member  of  [4908/] .  The  products  of  the  terras  between  the  braces,  in 
[4884, 4866],  are  found  in  the  following  table  ;  in  which  the  first  column  gives  the  terms  of 
[4884]  ;  the  second  column,  the  terms  of  [4866]  ;  and  the  third  column,  the  products  of 
these  terms  respectively  ;  using  the  abridged  notation  [482 1/J,  and  neglecting  the  same  terms 
and  angles  as  we  have  usually  done  ; 


[49086] 


[4908c] 


420 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4908] 


[4908'] 
[4909] 


Sm'.u'^ôu  .3j7r.(l+fe'2) 


2  F. 


2a. 


a,ôu     [4904]  ^  1 

—2A<^'\e.cos.(2v—2mv—cv+^)  |2 

-2A\'\e".cos.(2v—2mv—2cv-{-2^)  13 

+1  ^J"  .ee'.cos.  (2v—2mv—cv+c'mv+zi—ô,')  J  4 

+|J('>.ee'.cos.(2w— 2my— cy— c'mi>-f-a-f^')  v  ;, 

+|J|'^'.  -  .  e'.cos.(t' — mv-j-c'mv — -53') 


« 

f7 


+|-J,"^\  -.e'. COS. ft» — mi; — c'mt'+ra')  to 

'     '       a  ^  '  ^° 

+14"'-  -,.e'-.cos.(i'— m«)  /  9 


?{'  varies  by  means  of  the  variation  of  v' ,  Avhich  depends  on  the  time  ^,  and 
on  its  inequalities  in  functions  of  v  [4822,  or  4828]  ;  but  these  inequalities 
are  multiplied  by  m,  in  the  exjjression  of  v'  [4837],  and  also,  by  e',  in  the 
expression  of  v!  [4838]  ;    we   may,  therefore,  at  first,  neglect  (5m',    without 


[4908d] 


(Col.  1.) 

Terms  of  [4884]. 
1 


-e{  l-ic"2-i72)cos.«' 


(Col.  2.) 

Terms  of  [4866]. 

dioleof[4866] 

1 
— '3c.cos.cv 
-\-2e'.cos.c'mv 

— 3c.cos.cv 
-\-3c'. COS. c'mv 
-%-ce'  .COS. {cv-\-c'mv)\ 

fee'.cos.(cy-c'»iy) 
+3e2.cos.2fi' 
-^^y^.cos.2gv 
I — 3e.cos.fi' 
1 — 3e.cos.cv 


(Col.  3.) 

Products  of  these  terms, 
whole  of  the  function  [4866] 

—  ic2 a.72 

-|.(_[_je3+fc;2).cos.cy 

-}-( — ^c~e' — ^e'}'~).cos. c'niv 
— (  l+f  62_j.y2_|_^e/2)  .c.cos.cr 
-|-fc2  -\-^e^.cos.2cv 

— §ee'.cos.(c!) — c'7itv) — ^tc'. cos. (cv-^c'iiiv) 

-j-fe-e'.cos.c'my-|-&c. 


-\-^e~e'.cos.c'mv-\-&c. 

^C'^.COS.CV-^&LC. 

-|«»/2.cos.(2g'i'-cr)-)-&.c . 
-j-5e^.cos.2c«  1 — 3e.cos.cv  — ^e^.cos.cv  -\-ie^.cos.2cv~\-&Lc. 

-\-\y^.cos.^gv.  1 — 3e.cos.c«  ly-.cos.2gv  —^ey~.cos.{'2gv-cv)-\-&i.c. 

Connecthig  together  the  terms   which  are  e.Kphcitly  given  in  this  tahle,  with  those  between 
r4908('1     *'^*^  braces  in  [4866],  wliich  are  included  in  the  first  line  of  this  table;    the  sum  becomes 
equal  to  the  expression  between  the  braces  in  [4908/"]  ;  and  the  factor  of  a  ou  [4908a] 
becomes  as  in  the  second  member  of  [4908/"]  : 


VII.  i.  ^8.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  m.  421 

any  sensible  error.     We  shall  hereafter  [4947,  &c.]  notice  the  term  of  this 


variation,  which  depends  upon  the  action  of  the  moon  upon  the  earth. 


[4909'] 


3  m 

27, 


~\-  ( — 4  e — 3  e' — 6ee'  ®+e  y^)  -cos.ct 
+3e'.  (l+2e2+fe'^).cos.c'mj; 
— 3.(2-|-m)  .ce',  cos. (cv-\-dm  v) 
-3.(2 — m).ee'.cos.(cD — cfinv) 
-\-5e^.cos.2cv 
-\-y^.cos.2gv 
+fe'^.cos.2c'7«t) 
K — |e7^-cos.(2^« — cv) 

Muhiplying  this  by  a  Su,  we  obtain  the  value  of  the  function  [4908c(,  or  4907].  To  reduce 
this  to  the  form  [4908],  we  may  divide  the  terms,  between  the  braces,  by  l-j-#e'^,  and 
connect  this  with  the  factor  without  the  braces;  and,  by  neglecting  terras  of  the  fourth  order 
in    e,  e',  y,  between  the  braces,  we  get, 

l+2e2 

-j-( — 4e — Bt^-\-e  2^).cos.cv 
+3e'.  {l-\-2e^—^e'^).cos.c'mv 
-3. {2-\-m).ee'. COS. (cv-{-c'mv) 
— 3.(2 — m).ee'.cos(c« — c'mv)   \  .  aàu. 
-f-5e^.cos.2cD 
-|-7^.cos.2^i; 
-l-Se'^.cos.2c'mD 


3m'.u^.U 


31h.{l+ie'^) 
2a.  ' 


„,      .  3m'.(l+|e'a)      .      , 

1  he  factor —- — -   is  the  same  as 


2a 


le  7^.CGS.  (2^  t) — cv) 
[4908].     The  term   1,  between  the  braces  in 


[4908/] 


[4908g:] 


[4908^],  being  multiplied  by  the  external  factor  aSu,  produces  the  term    aSu  in  the  first 

line  of  [490S].     Now,    if  we   neglect  this   term  1,  between  the  braces  in   [4908^],  and    [4908A] 

multiply    the    remaining  terras  by    aSu    [4S04],    it   will    produce    the  terms  of   [4908], 

between  the  braces,  which  contain    A  explicitly.     In  performing  this  multiplication,  it  will 

only  be  necessary  to  retain  the  two  following  terms  of  [4908jg-]  ;  namely, 

—  4e.cos.cr-|-3e'.cos.c'mu.  [4908t] 

For,  the  other  terms,  between  the  braces,  are  of  the  second  order  ;  and  these  are  multiplied 


VOL.   III. 


106 


422 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4909"] 
[4910] 


3  m'  m" 
The  term     „,„'  , .  cos. (2 y —2^')     [4870],  has,  for  its  variation, 


9m'.M'3 


3m'.u' 


/„'3 


,     ^ . 6u. COS.  (2v  —  2v')  +  -— ^  .iv\sm.(2v—2v'). 

If  we  substitute  the  preceding  value  of  &u,  we  shall  find,  that  the  first  of 
these  terms  produces  the  function,* 


[4908fc] 


[4910a] 
[49106] 

[49i0c] 
[4910rf] 
[4910e] 

[4910/] 

[4910^] 
[4910A] 

[4910{] 


by  m,  of  the  second  order,  and  by  a  5m,  of  the  «etorao,  order  ;  proaucing  terms  of  the 
sixth  order;  some  of  which  may  be  reduced  to  the  Jifih  by  integration  [4847].  The  terms, 
depending  on  the  angle  » — mv,  of  higher  orders,  are  retained  as  in  [4874,  &lc.].  The  two 
terms  [4908J]  evidently  produce  those  in  [4908],  which  depend  explicitly  on  the  symbol 
A,  neglecting  the  terms  which  have  been  usually  rejected. 

*  (2815)     If  we  take  the  differential  of  [4885],  relative    to  dv,  and  multiply   it   by 


ia.dv 


,    we  shall  obtain  the  expression  of 


9ot'.u'3 
'  ihKu->.a 


.sin.(2« — 2v').      The  effect  of  this 

2 

operation  will  be  to  change  the  factor     3  m.—     [4885]   into     — - — ,     as    in     [4910  Ar]  ; 

moreover,  it  will  take  away  the  divisors  2 — 2m,  2 — 2m — c,  he,  which  were  introduced 
by  the  integration,  and  will  change,  in  tlie  second  member,  cos.  into  sin.  When  the 
function  is  reduced  to  this  form,  we  may  change  2v  into  2  y +  90'',  as  in  [4876a — d]  ; 
and  we  shall  obtain  the  expression  of 

9m'.  u'  3 


4hKu'>.a 


.cos.{2v—2v')     [4910k']. 


If  an  angle,  in  the  second  member  of  [4885],  be  of  the  form  cos.(2î)-}-(3),  it  becomes,  in 
[4910f/],  sin.(2i;+(3);  and,  in  [4910c],  it  changes  into  sin.(2«4-|3-|-90''),  or  cos.(2j)-f-^)  ; 
which  is  the  same  as  its  original  form  in  [4885].  But,  if  it  be  of  the  form  cos.(3 — 2v), 
the  successive  changes  are 

sin.(p — 2v),         sin.((3— 2« — 90''),     and     — cos.(p — 2v)  ; 

this  last  being  the  same  form  as  the  original,  but  with  a  different  sign.  Hence  we  easily 
derive  the  expression  [4910^]  from  [4885],  by  using  the  factor 

neglecting  the  denominators  2 — 2  m,  Sic.  [4910c],  and  changing  the  signs  of  the  terms 
depending  on  angles  of  the  form    cos. ((3 — 2d)  ; 


VIL  i.  «5- s.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u. 


423 


^'"'■%.5u.cos.(2v—2v') 


'2h^.u* 


9m 


4a. 


4°>.(l-|e'=^) 

+  { Ji"-44''^ +4='-Mf -e'^+J^r'-f ''}  •«•(1-f  «'')-cos.  (c» -«) 
+  { S^o'+^^'J+Jt^'  I .  e'.  COS.  (c'  m  v—^) 

i_[_^4') — iJ<'>].ee'.cos.(cw+c'/«i' — ^ — ^) 

+  -^f  •  e e'.  COS. (2  v — Imv — c  t) — c'mî;+«-}-a') 

+  ^<^' .  e  e'.  COS.  (2  « — 2  m  w — c  v-\-dm  v-\--a — to') 
\+{^J""+i(2+?tt).  J;"-2(  1  +«0.^"'  I  .e/^cos.(2o-zj-a'-2i)+TO)^' 
1+4'^'.  67^.  COS. (2  z? — 2mt5 — 2^w+ct)+2â — a) 

+  { Jf^— i^'^'.e'^j.  -,.  cos.(«— OT  z)) 


+  {4"'— è4"'l.-.e'.cos.(i;— m2;+c'm?)— to') 
+  {4'3)+^'J(/^)^.-,.e'.cos.(«— mtJ— c'mtJ+TO') 


1 
2 
3 

4 
5 
6 

7     [4911] 

8 

9 


10 
11 
12 


4  A^  vr.a         ^  ' 


9m_ 
4a, 


/(l+2e2— |c'2).cos.(2d— 2mD)  V     1 

-2(l+m).(l+Je2-iy2-fe'2).e.cos.(2«-2mj;-c!;) \   2 
— 2(1 — m).e.cos.(2y — 2mv-\-cv)  I  3 

+Je'.cos.(2i; — 2m« — c'otw)  I  4 

-Je'.cos.(2j; — 2m«-j-c'?n«)  f   5 

^ — J(2+3m)  .ee'.cos.(2v—2mv—cv — c'mv)  I    6 
-f(2— 3m).ee'.cos.(2u — 2mv-\-cv — c'înv)  1     7 
+|(2-j-m)  .ee'.cos.(2« — 2«t)— cjj-fc'mv)       \- 8   [4910/t] 
1+1(2 — m)  .ee'.cos.(2«) — 2mv-{-cv-{-c'mv)      /    9 
/+ï(10+19/«+8OT2).e2.cos.(2ct;— 2j;+2mi')     10 
'+i{l0~19m^8m%e^cos.(2cv-\-2v—2mv)\ll 
+i(24-m).j^.cos.{2gv—2v-\-2mv)  Il2 

+i(2—m). 72.003.(2^ D+2  v—2mv)  Il3 

+^.e'3.cos.(2î)— 2mi;— 2c'7«»)  /l4 

\ — î(5-j-m).ey®.cos.(2î; — 2mt) — 2gv-\-cv)     /  15 


424  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4911']    aèu     contains   a  term,    depending  on     cos.  (3t) — Smv),     which  we   have 


[4910i] 


Multiplying  the  first  member  of  this  expression  by     2.a6u,    and  the  second  by  its  equivalent 
expression  [4904],  we  shall  obtain,  by  making  the  usual  reductions,  the  value  of  the  first 

term  of  [4910],  as  in  the  second  member  of  [4911].      For,  the  factor,  without  the  braces, 

a 
97/1 
[4910m]    —  ' — ,     is  the  same  in  both  these  functions  ;  we  shall,  therefore,  neglect  the  consideration 
4  a, 

of  it  in  the  remainder  of  this  note  ;  and,  in  speaking  of  the  functions  [4910A:,  4911],  shall 
[4910n]  refer  exclusively  to  the  terms  between  the  braces  ;  and,  shall  separately  investigate  the  results 
arising  from  each  line  of  the  function  2-a&u  [4904],  by  the  ivhole  of  the  function  [4910A:]. 
First.  We  shall  take  into  consideration  the  product  of  the  term  2  ^g'*. cos. (2 a; — 2mv), 
by  the  whole  of  the  function  [4910fc]  ;  and  shall  reduce  the  products  by  formula  [20]  Int., 
retaining  the  same  angles  as  in  [4911].  The  first  line  of  [4910A:]  produces  the  term 
(l-[-2e^ — Je'^)..42"";    the  part  depending  on    cos.(4t) — 4 ??(«;)     being  neglected.      This 

2 

corresponds  to  the  first  line  of  [4911],  neglecting  the  part  depending  on  7/t  .c^.^,'*,  of 
[4910o]  the  sixth  order,  as  is  done  generally  in  the  rest  of  this  calculation  ;  the  term,  depending 
on  fe'®,  is  retained,  on  account  of  its  importance  in  the  secular  equations  of  the  moon's 
motion  [4932, 5059, 5087,  &.c.].  Again,  if  we  neglect  e^  y^  in  the  factor  [4910/1] 
line  2,  and  introduce  the  factor  (1 — Je'~)  in  [4910À:]  line  .3,  according  to  the  directions  in 
[4869^, fee],  we  shall  find,  that  these  terms,  when  multiplied  by  2A.j°\cos.{2v — 2mv), 
produce  respectively  the  terms 

—  2.(l+m).(l— Je'S).^/'.  e.cos.ct;,         — 2.(1— m).(l -Ae'^)  .^^w.e.cos.ct;  ; 
whose  sum  is 

—  4.(1— fe'2).^2°'icos.ct),     as  in  [4911]  line  2. 

In  like  manner,  the  terms  in  [4910^]  lines  4,  5  being  multiplied  by   2jÎ^°\cos.{2v — 2mv), 
produce  respectively  the  terms 

^A.;^°\e  .COS. cm V,         — l^^'^'.c'. cos. c'mo  ; 
whose  sum  is 

3AP.  e'.  cos.  c'm  v,     as  in  [491 1]  line  3. 

the  remaining  terms  of  the  function  [4910fc]  may  be  neglected,  on  account  of  their  smallness, 
and  the  forms  of  the  angles. 

Second.     We  shall  now  compute  the  terms  produced  by  multiplying 
2.^,<'\  e  .cos.(2v— 2  m  v—cv)     [4904], 
by  the  terms  of  [4910/*:].     The  first  line  of  [4910A-]  produces     .^i<'\  e  .  (1— Je'^) .  cos.  c  v, 
as  in  [4911]  line  2.  The  second  and  third  lines  of  [491  OAr]  depend  on  c^,  which  is  neglected. 
[4910/)]     The  fourth  line  of  [4910^::]  gives     iee'.Ai^'\cos.(cv—c'tnv),    as  in  [4911]  line  4  ;  the  fifth 
line,    — ^  e b. Jli-'\ COS. {cv-]-c' m v),     as  in  [4911]  line  5;  and  the  twelfth  line 
}  {2-\-m)  .ey^.cos.{2gv — cv),     as  in  [4911]  line  8. 


VII.  i.  ■§  8]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  425 

neglected,*  on  account  of  its  smallness  in   [4904]  ;  but,  as  it  may  have  an 
influence  in  the   term  depending  on     cos.(îj — mv),     we   shall  take  notice     t*^^^'^ 


The  other  terms,  depending  on     ►?/'>,    are  neglected,  on  account  of  their  smallness,  &ic. 
Third.     The  product    of  2J.r-''.e.cos.{)îv—2mv-\-cv)     [4904],  by  the  first  term  of 
[4910t],  produces  the  term     A./~le.  {l—ie"'}.co5.cv,    as  in  [4911]  line  2.      This  is  the     [^910?] 
only  term  depending  on     ^.f\    which  requires   attention  ;   the  other  terms  being  small,  or 
of  forms  which  are  unnoticed. 

Fourth.     The  product  of    2  Jl/^Ke'. cos. {2 v— 2 7JIV+ cm v)    [4904],  by  the  first  term  of 
[4910A],  produces   the  term     Ji.^^^'.e'. cos. c'mv    [4911]  fine  3;    the  other  terms  maybe 
neglected.    In  like  manner,  2^a<".e'.cos.(2«—2/?iu—f'mî;)   [4904],  produces    w3^«.e' cos.c'mw     [4910r] 
[4911]  line  3;  and  2.^2'^'.  e'.  cos.  c'otd  [4904],  gives  nothing  deserving  of  notice. 

Fifth.  The  terni  2.,'î/'''  ce'.co3.(2(; — 2mv — cv-\-c'mv)  [4904],  being  multiplied  by  the  first 
term  of  [4910Â:],  produces  ^/'".ee'.cos.(ct' — c'mv)  [4911]  fine  4;  and  the  same  term, 
being  multiplied  by  the  fifth  term  of  [4910A-],  produces  — \ee'^.A['^\cos.cv;  which  is 
nearly  the  same  as  in  [4911]  line  2.     In  like  manner,  the  term  [4910s] 

2.4/''.  e  e  .  cos.(2î) — 2mv — cv — c'niv), 
being  multiplied  by  the  first  and  fourth  terms  of  [4910A-],  produces  the  terms 

Ap.cc'.cos.{ci'-\-c'mv),     and     -{-lJlp\ee'^.cos.cv;     as  in  [4911]  lines  5,  2. 

Sixth.  The  terms  depending  on  Ai^\  .4/°'  [4904],  being  combined  with  the  first 
term  of  [4910A-],  produce  the  terms  [4911]  lines  6,  7.  Those  depending  on  ./^a'"^  ./3/'", 
^.2"^',     produce  small  terms,  which  are  not  noticed.     The  term 

2A\^'>K',^.cos.{2gv—2v+2mv), 
being  combined  with  the  term  — 2.(l-j-7?i).c.cos  (2« — 2mv — cv)  [4910A-]line  2,  produces 
the  term  depending  on  ^4,"^'  [4911]  line  8.  The  term  depending  on  A.^^*^  [4904],  produces 
nothing  of  importance. 

Seventh.     The  terms     2.â^^^^\ey-.cos.{2gv—cv),     2Ai^"^\ef.cos.(2v—2mv—2gv-j-cv) 
[4904] ,  being  combined  with     cos.(2y — 2mv)   [4910/i:],  produce  respectively  the  terms  in     [-lOlOu] 
[4911]  fines  9,  8,  depending  on    .^J'^',     .4/"". 

Eighih.     The  term|,-2.,3/'^'.cos.(D— mu),    being  combined  with  the  terms   in  [4910/^-] 
lines    1,  5,  4,  produces    the  terms  depending  on     .4/'"',      in    [4911]    lines   10,  11,  12,     [4910r] 
respectively. 

JVinth.     The  first  term  of  [49101],  being  combined  with  the  terms  of  2.aûu    [4904], 
depending  on    .^o*'^''     -^o™.     produces  the  corresponding  terms  of  [4911]  fines  12,  11.  [4910u>] 


[4910<] 


*  (2816)     This  term  occurs  in  [4808],  and  must,  therefore,  be  found  in  the  differential 
equation  in  u  [4754] ,  and  in  its  integral  5u,  or  a  ou. 

VOL.  III.  107 


[4911a] 


426 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


of  it.     For  this  purpose,  we  shall  put  it  under  the  following  form  ; 


[4912] 

[4912'] 

[4913] 
[4914] 

[4914'] 
[4915] 
[4916] 


Term  of  aiu=^'^^ 

Substituting  this  in  the  expression 
it  produces  the  term,* 

2 

9  w  ( 

Aa,       ^   i 


-  .cos.(3t;— 3«'). 


^^,.6u.co^.{2v—2v')     [4910], 


To    develop    the   variation 


A2.m3    • 


-.  cos.f» — mv). 
a  ^ 

iv'.ûn.{2v  —  2v')      [4910],     we    shall 


observe,  that  iv'  contains,  in  [4837],  the  same  inequalities  as  the  expression 
of  the  moon's  mean  longitude,  in  terms  of  the  true  longitude  ;  but  they  are 
multiplied  by  the  small  quantity  m.  It  is  sufficient,  in  this  case,  to  notice  the 
terms  in  which  the  coefficient  oïv  differs  but  little  from  unity;t  and  it  is  evident 
that  as  the  term  e.cos.(ct) — ^n),  of  the  expression  of  «i<  [4826],  gives,  in  v',  the 
termj  — 2me.s'm..{cv — ra)  ;  any  term,  whatever,  of  af>u,  such  as  A;.cos.(ù"-|-£), 


r4913ol         *  (^Sl"^)      Substituting     the    values    of    m,    u' ,    [4791],  and    h^  =  a,    [4863],    also 
v'=^mv  [4837]  nearly,  in  the  expression   [4912'],  it  becomes 


[49136] 


9) 


2a,.<i'3 


—.aSii.cos.(2v — 2d')  =  —  "-— .a5u.cos.{2v—2mv)     [4865]. 


If  we  now  substitute  the  term  of  aSu  [4912],  we  obtain  that  in   [4913],    and   also  one 
depending  on  the  angle     5  v — 5  m  v,     which  may  be  neglected. 

t  (2818)  We  shall  see,  in  [4918],  that  the  terms  of  this  form,  in  which  the  coefficients 
[4914a]     of  V  are  nearly  equal   to  unity,  produce  only  small  quantities  of  the   fifth  or  sixth    order. 

These  terms  are  noticed,  because  they  are  much  increased,  by  integration,  in  finding  the 
[49146]     value  of  u  [4841]  ;  but  this  does  not  happen  with  the  terms  in  which  the  coefficient  of  » 

differs  considerably  from  unity  ;  and  we  may  also  observe,  that,  in  this  last  case,  the  terms 
[4914c]     may  also  be  decreased  by   the  integration   in  [4822].      Hence,  we   see  the  propriety  of 

noticing  only  the  terms  mentioned  by  the  author  in  [4915]. 

X  (2819)  If  we  inspect  the  calculation  in  [4812  —  4837],  we  shall  find,  that  the  term 
[4915a]     c.cos.(c«;— ra),  which  occurs  in  u  [4812,4816,  4819, 4826],  is  introduced  into  dt  [4821],  and 

by  integration,  produces  in  t  [4822],  or  rather,  in  nt-\-s  [4830],  a  term  — 2c. sin. (en — w). 
[49156]     rpjjjg  jg  j-,;iu]^piied  by  m  in  the  second   member  of  the  equation  [4836]  ;    and  it  finally 

produces  in  v'  [4837],  the  term  — 2?»e.sin.(cj; — 13),  as  in  [4916].  This  may  be  derived 
[4915c]     f,.Q,j^  {],g  preceding  term   of  u,  by  changing  cos.  into  sin.  and  multiplying  the  result  by 


VII.i.§8.]    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  m.  427 


ill  which  i  differs  but  little  from  unity,  gives  very  nearly,  in  dif,    the  term 

2mk.sm.(iv-{-s).     Thus  we  find,  that  the  preceding  term  [4914]  gives,  by 

its  development,  the  function,* 


[4917] 


— 2  m.     Tlie  same  method  of  derivation  may  be  used  with  any  other  term  of  u,  in  which 

ihe  coefficient  of  v  diflers  but  little  from  c,  or  from  unity  [48286]  ;  as  is  the  case  with  the     [4915d] 

term     ^•.cos.(^•»-)-s)     of  u  [4916],    which    produces,  in  Sv',  the  term    — 2mk.sm.(iv-{-s) 

14917]. 


*  (2820)  Instead  of  the  angle  iv-\-s  [4916,  Sic],  we  shall,  for  brevity,  use  iv,  omitting 
s,  as  we  have  to,  -n',  6,  in  [4821/],  and  re-substituting  it  at  the  end  of  the  calculation. 
Then,  if  we  represent  any  term  of  ai5w  [4904],  in  which  i  differs  but  little  from  unity,  by 
a5u  =  Ji:cos.iv  [4916],  the  corresponding  term  of  5v'  will  be  very  nearly  represented  by 
^i)'= — '2m  k.s'm.iv  [4917].  Moreover,  if  we  represent  any  term  between  the  braces  of  the 
second  member  of  [4876e],  by    As'm.V  ;    or,  in   other  words,  any  term  of  the  function 


A2.u3 


—  .sin. (2» — 2v')     by 


.^.sin.F; 


and  then  multiply  it  by  the  preceding  expression  of  5v',  we  get,  by  using  [17]  Int., 

—^ .5i''.sin.(2c — 2î)')= .^AmJc.cos.(iv'-^T^) — Am'k.cos.{i  v-{-V  )\ . 

The  factor,  without  the  braces,  is  the  same  as  in  [4918]  ;  consequently,  the  terms,  between 
the  braces,  in  [4918],  must  arise  from  the  other  factor  of  [4918/]  ;  namely, 
A mk.cos.{iv>xy^  — A mk.cos.{iv-}-V)  ; 

in  which  we  must  substitute  the  terms  of  a&u  [4904],  for  k.cos.iv;  and,  the  terms  between 
the  braces  in  [4876e],  for  .^.sin. K;  neglecting  the  terms  which  are  insensible  from  their 
smallness,  or  those,  where  the  coefficients  of  v,  in  the  angles,  vary  much  from  unity  [4915]. 
We  shall,  in  the  first  place,  compare  the  terms  of  the  function  [4918^],  with  the  terms 
between  the  braces  in  [4918],  taking  successively,  for  k,  the  coefficients  of  the  terms  [4904], 
which  are  retained  by  the  author.  First.  The  term  .^/".e.cos.(2« — 2mv — cv)  [4904], 
corresponds  to  /i;=./î/'^e,  iv  =  2v — 2mv — cv;  combining  this  with  the  first  line  of 
[4876e],  neglecting  e^+i)-^,  we  find  that  this  first  term  of  [4918^]  produces  the  first  line 
of  [4918].  If  we  combine  the  same  term  of  [4904]  with  the  first  term  in  line  13  [4876e], 
we  find,  that  the  second  term  of  [4918^]  produces  the  second  hne  of  [4918].  It  is 
unnecessary  to  notice  the  products  of  the  other  terms  of  [4876e],  by  the  term  [4918A:]  ; 
because  the  coefficients  are  small,  or  the  angles  are  different  from  those  which  are  usually 
retained.  Second.  The  term  Af)^^^\e'y^.cos.[2gv — cv),  being  combined  with  the  first 
tenu  of  [4876e],  produces,  by  means  of  the  first  term  of  [4918o'],  the  third  line  of  [4918]. 


[4918a] 
[49186] 

[4918c] 
[4918rf] 

[4918e] 


[4918/] 

[4918gr] 
[4918^] 

[491 8i] 

[4918A:] 
[4918i] 

[4918m] 
[4918n] 


428  THEORY  OF  THE  MOON  5  [Méc.  Cél. 

m.J/".e.(l— |e'-).cos.(ci'— î3)  .     1 

+^.m.A[^\ef.cos.(2gv — cv — 20+13)  |   2 

3wtt^     ,    .     .^       ^   .  3w     / +'/».^''"'.e?^  .COS.  ,        ,  CI.    °     1     I     3 

[4918]  ■^j^.'V.sin.(2t;— 2i;')-=— ^^-^    '         "      '  V      +cv+2l—^  J     \ 

-\-m.A\"\-.cos.(v — mv) 

a  ' 

-j-m.Al^^K-.e'.cos.(v — mv — c'm^7+3') 
The  other  terms  of  this  development  are  insensible. 
The  terms 

a  m'  ni'  i 

.\2.cos.{v—v')+5.co&.(3v—Qv')\, 


[4919]  Qh^.u^ 

of  the  expression 


|.^gjg       Third.     The  term     AP''\ -, .  cqs.{v — mv),     [4904],    combined  with    the   first    temi    of 
[4876e],   produces,  in    like   manner,    the    fourth    line    of    [4918].     Fourth.     The  term 

r4918ol    •^o"*'- ",-fi'-cos.(i; — mv-\-c'mv — is')     [4904],  combined  witii  tlie  same  first  term  of  [4876eJ, 
produces  the  fifth  line  of  [4918]. 


[4918c] 
[4918r] 


It  appears,  from  [4840,  &c.],  that  the  terras  in  the  five  lines  of  the  function  [4918],  are  of 
the  orders  5,  7,  6,  6,  6,  respectively.  The  integration  [4847],  introduces  divisors  of  the 
order  m^  [4828e],  in  the  first  and  second  lines  of  [4918],  and  of  the  order  m,  in  the  other 
three  lines.  By  this  means,  the  first  line  of  [4918]  produces,  in  the  value  of  u,  a  term  of 
the  third  order,  and  the  other  lines  produce  terms  of  the  fifth  order  ;  which  are  within  the 
limits  proposed  in  [4905',  &c.].  With  respect  to  the  order  of  the  terms  which  have  been 
neglected,  we  may  observe,  that,  in  calculating  in  [4918Z]  the  quantity  produced  by  one  of 

[4918s]  the ^rea<es< terms  of  [4904]  ;  namely,  .^"\e.cos.(2y — 2mu — cv),  when  combined  with 
the  greatest  term  of  [4876e],  contained  in  its  first  line,  we  have  noticed  only  the  first  term 
of  the  function  [4918^],  and  neglected  its  second.  This  second  term  has  the  same  coefficient 
of  the  fifth  order,  as  in  the  first  line  of  [49!  S],  but  the  quantity  cos.c»  is  changed  into 
cos.(4w — Amv — cv)  ;    making   2^4 — 4m — c^=.3,  nearly  [4846]  ;    and  the  divisor    P — JV^ 

[4918u]  [4847]  becomes  so  large,  that  the  corresponding  term  is  much  decreased,  so  that  it  may  be 
neglected.     Similar  results  will  be  obtained  relative  to  the  other  neglected  terms. 


[4918<] 


VII.i.^3]  DEVELOPiMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  429 

have,  for  variation,* 

2 

—  '"^ "'/""".  -, . {3.cos.(«— miO+5.cos.(3 v—Smv)].  [4921] 

Substituting    AfKcos.(2v — 2mv),     for     aôu,     we  obtain  the  term,t  [4921] 

2 

a,        -      «, 
The  variation  of  the  term  [4876], 


3  m'.  U'^       du  .         ,n  r,     IS 

jj^^.-.sm.(2v-2v),  [4923] 


*  (2821)     The  variation  of  [4919],  relative  to   u,  which  is  the  most  important  part  of 
this  expression,  as  we  shall  see  in  [4922;],  is 

—'-rrr^-^uA3.cos.(v—v')4-5.cos?(v—v')].  [4921al 

If  we  neglect  terms  of  the  order  e,  we  may  substitute  the  values  of  u,  ii'  [4791],    h^  =  a, 

2 

[4863],  and    7/1      [4S65],  in  the  factor,  without  the  braces,  and  it  will  become, 

2 

3m'.u'*.Su  „  m'.«3    aiiu  a  37n  .aôu    a  .     ,..„„  -, 

o^o    5      =—i-— 7^  •  —  ■-,= 7, •-'     as  m  [4921].  [49216] 

2/i2.M5  ■^     a  3         a,     a'  '■Za^  a  ■■  -■  '■  -' 

]Moreover,  by  putting  v'^mv    [4837],  in  the  terra  between  the  braces  [4921  «],  h  becomes     [4921c] 
as  in  [4921]. 

t  (2822)     Taking,  for    aSu,  its  first  term  [4904];  namely,    aSu^A':?\cos.{2v—2mv), 
we  get,  by  noticing  only  the  angle  v — mv,  which  requires  particular  attention,  as  is  observed    [4922a] 
in  [4874,  &ic.],  we  obtain, 

n5«.3.cos.(u — mv)  =  ^Aj^Kcos  {v—mv)  ;     aki.5.cos.{3v—3mv)z=^A:i°\cos.{v—mv);       [49226] 

whose  sum  is    AA.2^''\cos.{v — mi-).      Substituting  this  in  [4921],  it  becomes  as  in  [4922].     [4922c] 
The  remaining  terms  of  aùu  are  of  the  second,  third,  &c.  orders;  and,  when  multiplied  by 

2     a 
the  factor     »»  •  ^,     they    become  of  the  sixth,    seventh,  &ic.   orders,  which   are  usually 

[4922rfl 
neglected.     If  we  notice  the  variation  of  v',  in   [4919],  it  will  produce  terms  of  an  order 

equal  to  those  in  [4921],  multiplied  by  the  factor     —  ,     which    factor  is  of  the  order   m 

"  [4922e  1 

[4916,4917];  so  that,  the  terms  produced  by    oV,    will  be  less  than  those  retained  in 

[4921,4922],  and  may,  therefore,  be  neglected. 
VOL.  III.  108 


430 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4924] 


may  be  reduced  to  the  following  terms  ;* 

6:ii.iP      (In      ÔU       .        ^         ^     ,^  3m'. u'^      dSii 


dv      u 


+ 


Sm'.u'Uv'     du 

--.cos.(2î;-2î;'); 


A^.i 


dv 


these  terms,  bj  development,  produce  the  following  expression  ;t 


[4922/] 


[4923a] 

[4923i] 

[4923c] 


[4923rf] 
[4923e] 

[4923/] 

[4923^] 
[4923/i] 

[4923i] 


*  (2823)  The  term  [4923],  is  the  same  as  that  whose  approximate  value  is  computed 
in  [4876,4879].  Its  variation,  considering  u,  du,  v',  as  variable,  and  neglecting  &u',  as  in 
[4909],  becomes  as  in  [4924]. 

t  (2324)  Multiplying  the  equation  [4S84]  by  — 2  Su,  we  get,  by  using  the  abridged 
notation  [4821/], 

4  rÎM  4  nSu  f        c  .         ,  ,    „         J 

or i^ftdM.j — 4-4-4 e.cos.ci'+&ic.  (. 

Multiplying  this  by  the  function  [4879],  we  get  the  expression  of  tlie  first  term  of  [4924]. 
Now,  the  function  [4879]  is  of  the  third  order,  and  ahi  [4S04]  is  of  ihe  second  order; 
therefore,  if  we  retain  only  the  two  terms  — A-\-Ae.cQs.cv  of  tlie  factor  [4923«],  the  final 
product  will  be  correct,  in  the  sixth  order.  We  may  even  neglect  the  term  4  c.cos.îj  ; 
because,  when  it  is  multiplied  by  tlie  two  greatest  terms  of  [4879]  lines  1,  2,  it  produces 
terms  depending  on  e-. cos.  (2d — 'i.mv),  which  mutually  destroy  each  other;  also, 
terms  of  the  order  c-,  connected  with  the  angles  2;; — 2/««j;2c«,  which  do  not  increase  by 
integration,  and  are  neglected  in  [491 1  ,&c.].  Hence,  the  first  term  of  [4924],  is  represented 
as  in  [4923a,  i],  by  the  following  function  ; 


6m.  «3     du     iu 

-TTT-r  ■  -r-  ■  —  .sm.(2i' — 2v)  =■ 


-4.« (5m  X  function  [4879]. 


It  is  only  necessary  to  notice  the  terms  A.^\  Ji[^^,  ^J'^\  in  the  value  of  a  i5m  [4904]; 
because,  the  function  [4879]  is  of  the  third  order,  and  the  other  terms  A'w^'e,  A.^^^c,  &.C. 
are  of  the  third,  or  higher  orders;  so  that  their  products  are  of  the  sixth,  or  higher  orders, 
which  are  neglected.  The  reason  for  retaining  the  term  .^/'^'  is,  because  it  is  connected 
with  the  angle  'igv — cv,  and  is  much  increased  by  integration  [4828r/].  Now,  the  part  of 
— 4. «(5m  [-1904],  depending  on  A"",  is  — 4^o"'\cos.(2u — 2mv).  If  we  multiply  this  by 
the  first  line  of  [4879],  between  the  braces,  neglecting  c^,  we  shall  get  the  term 

— 2  cc^2W'.(l— fe'2).cos.(c«)— ra)  ; 
and  the  second  line  of  [4879],  retaining  the  factor  [4879^'],  produces  the  same  term,  with  a 
different  sign  ;  so  that  these  terms  mutually  destroy  each  other.  The  other  terms  produced 
by  .^o'"',  are  too  small  to  be  noticed,  or  depend  on  angles  which  may  be  neglected.  The 
product  of  the  term  — 4.^i'''e.cos.(2w — 2mv — cv),  in  — 4.aSu  [4904],  by  the  tenth  line 
of  [4879],  between  the  braces,  produces  gA^'^ ej^. cos. {2 gv — cv).    Finally,  the  product  of 


VII.  i.  §8]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  431 


2.(1— m).2r.(l— |e'2) 

l+^{^-3»i—c).J'p.e'^—l{2-m-c).^f'.e"'  S 
+  J6.(1— mJ.^f+(2— M)-2f+(2— 3m)..^|'"}.e'.cos.(c'm«-^') 
_)_  I  (2_3m_c)  .^;')_à  (2— 2m— c)  ../^i"  I  .ee'.cos.  (cD+c'my -a -ra') 
\-\-l{2—m—c).J.f-\-l{2-~2m—c).J'-p}.ee'.cos.{cv—c'mv-a+-a') 
'-j-(c — m)..4i^'.ec'.cos.(2w — 2m!; — cv-{-c'mv-\--a — to') 
3ml  -\-{c-}-m).^f\ee'.cos.{2v — 2mv — ct— c'mr+tô+ra') 
^"'"\  ,  Ci(4-+4+m-2c)^f"— 2(1— 2m).^i'3'j 
'  "  ^  _[_  (2— 2m— 2^-f  c)-^l'«'  < 

/+^i5).C"^2_cos.(2i>— 2m«— 3^w+c«+23— n) 


.  ey^.  cos.(2o-i; — c» —  2è-\-a)' 


-{-\{\-2m).^™—h{'^—m).A[^''^.-,.e'.cos.{v—mv+c'mv—-a') 

,  _|_^  JTO1+  J {l—m).Â[^'^ .-,.e'.cos.{v—mv—c'mv-^T^') 


4^/'3y2.cos.(2^r— 2r4-2mr),     in     —A.aSu     [4904],    by  the  first   term  of  [4S79], 

between  the  braces,  produces    — 2^,'^'^''e-y^.cos.{2gv—cv).      Substituting  these  two  terms 
in  the  second  member  of  [4923e],  we  get, 


6m'.  u'3      du    du 


3 


h^.  u*       dv      u 


.sm.{2v  —  2v)  =  ~  .{{gA^'''^—2AP^^^).ey^.cos.{2gv—cv)]. 


[4923ft] 


The  third  term  of  [4924], 


A  a, 

3m'.M'3.'Iu'      du  /r,  n    r\  i  i 

.  —  .  COS.  {2.V  —  2v),      produces  only   a  very     [4923^] 


/Au'î      '  dv 

small  quantity,  depending  on  the  same  angle  as  in  the  preceding' expression  [4923^].      Now, 

without  taking  the  trouble  to  compute  the  whole  development  of  this  third  term,  we  may 

form  a  satisfactory  idea  of  its  value,  by  taking  the  product  of  the  two  functions  [4878,4918]; 

which  gives  the  expression  of 

3m'. u'3.  iv'     du     .    ,_        _   ,, 
.  --  .sm.(2D — 2v)  ; 


A3.  M-» 


dv 


[4923m] 


and,  as  this  differs  from  [49237]  only  by  the  change  of  cos.  into  sin.  in  its  last  factor,  it  is 
evident,  that  the  two  functions  will  produce  terms  of  the  same  forms  and  orders  ;  so  that, 
what  may  be  neglected  in  the  one,  may  also  be  neglected  in  the  other.  Now,  the  greatest 
term  of  [4878],  independent  of  its  sign,  is    ce.sin.cw  ;    and,  if  we  multiply  it  by  the  terms 


432  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4926]     The  expression  of     (j^)-j^j      [4754],     contains    also    the    following 


of  [4918],  we  obtain  only  quantities  of  the  sixth  order,  depending  on  angles  which  may  be 
neglected.  The  remaining  terms  of  [4878]  are  of  the  second  or  higher  orders,  producing 
terms  of  the  seventh  or  higher  orders  ;  therefore,  they  may  all  be  neglected,  excepting  one, 
depending  on  the  angle  2gv-cv,  which  is  retained  for  the  reasons  stated  in  [4828(/].  A  term 
of  this  form  is  produced  in  the  function  [4923m],  by  multiplying  the  term  in  line  4  [4878], 
which  is  nearly  equal  to    ^■)'^.s'n\.2gv,  by  the  term  depending  on  ^'^h,  in  the  expression  of 

^'"'"  "\sin.  (2y— 2u')  .5v'     [4918]  line  1. 


[4923ȕ] 


Hence,  it  is  evident,  by  a  similar  process,  that  the  terms  of  the  function  [4923/],  depending 

[4923o]     on  the  angle    2gv — cv,  may  be  found,  by  multiplying     ^-y^.s'm.Qgv,  by  the  terms  depending 

on    A'-^''e ,    in  the  function         .,    -   ,-, 
[4923^.]  3m^  _  ^^^_  (2«_2t,')  . &v'. 

Now,  the  term  depending  on     ^/"e,     in  the  expression  of    aSu    [4904],    is 

a  5u=:  ^/*'.e  .cos.(2y — 2mv — cv)  ; 
the  corresponding  term  of  &v'  [4916,4917],  is 
[4923;?']  &v'  =  —2  ^/I'.m  e.sm.{2v—2mv—cv). 

Multiplying  this  by  the  chief  term  of 

Âa  "   •<^os.(2i) — 2v')  [4870],  which  is,     ^-^.cos.(2« — 2/?ii'), 

we  get,  in  the  function  [4923j(],  the  term 

_a 

.  A.^^'.me.sm.cv. 

Finally,  multiplying  this  by  the  factor  iy^.sm.2gv  [4923o],  we  get,  for  the  third  tenu  of 
[4924],  the  following  expression  ; 

[4923g]  3,Môv'     du  _        ^  ^ .lm.A,^^\ef.cos.(2gv-cv)]. 

We  shall  now  develop  the  second  term  of  [4924],  which  is  the  most  important.     It  may 
be  put  under  the  following  form  ; 

3m'.«'3     dhn  C    3w'.«'3       .     ,„    '         „  >     d.[ahu) 

The  factor  between  the  braces,  in  the  second  member  of  this  expression,  connected  with  the 
negative  sign,  is  evidently  equal  to  the  differential  of  the  first  member  of  [4885],  divided  by 
2.aàv  ;  and  if  we  perform  this  process  on  the  second  member  of  [4885],  we  shall  find,  that 

2 
o  — 

[4923s]     the  division  by  2a,  makes  the  factor,  without  the  braces,  become  — — .      Moreover,  by  taking 


VlI.i.^,8.J    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  433 


variation  ; 


the  differential  of  the  terms  between  the  braces,  the  divisors  2 — 2m,  2 — 2m — c,  &ic., 
which  were  introduced  by  the  integration,  are  effaced,  and  cos.  is  changed  into  — sin.  ; 
so  that,  if  we  represent  any  term,  between  the  braces  in  ['1885J,  after  effiicing  the  divisors, 
by  Ic'.cos.v'  the  corresjionding  term  of  the  first  factor  of  the  second  member  of  [4923r], 
will  be  represented  by  a  series  of  terms,  of  the  form 

_2 

3  »i 


.—  IJlL.k'.sm.v'     [4923«,m]. 


2a 


Now,  putting    aSu    equal  to  a  series  of  terms  of  the   form    k.cos.(iv-\-!)     [4916],   or,  for 


brevity,  A-.cos.?"«    [49I8i],   the  corresponding  term  of 


d.{a6u) 
dv 


will    be 


■ik. 


Multiplying  this  by  the  first  Aictor,  which  is  given  [492;3y],  we  get  the  following  expression 
of  the  function  [4923r],  or,  of  the  second  term  of  [4924]  ; 

2 

^m'.u'^      d  6u      .      ,  3  in 

— .  sm.  (2  v—2  v)—  —.  \ikk'.cos.(iv  w  v')—{kk'.  cos.{iv-\-v')  ] . 

_s  ' 

3  m 


The  factor  without    the   braces 


is   the    same  in  all  three  terms   of  the    functions 


[4923.1-,  y.x]  ;  and  is  equal  to  that  in  [4925];  we  shall,  therefore,  neglect  wholly  the 
consideration  of  this  factor;  and,  in  speaking  of  these  functions,  shall  limit  ourselves 
exclusively  to  the  terms  within  the  braces.  These  terms,  of  the  function  [4923i],  are 
represented  by, 

ik.  jt'. cos.(/y  m  v') — t'.cos.(it)-f-v')  |  ; 

m  wliich  k.cos.iv  represents  the  terms  of  [4904],  cui'l  k'.cos.V  the  terms  between  the 
braces  in  [4885],  rejecti7ig  the  divisors  2 — 2m,  2 — 2m — c,  he.  which  ivere  introduced  by 
the  integration. 

We  shall  now  take,  for  ^.cos.iy,  the  terms  of  the  function  [4904]  ;  so  as  to  combine 
successively  each  of  the  symbols  Xj'"',  .^/",  &.C.  with  all  the  terms  of  [4885].  We  shall 
neglect  the  terms  which  appear  to  be  insensible,  and  shall  compare  those  which  are  retained 
with  the  function  [4925]  ;  taking  the  terms,  depending  on  .^a"",  ^^o'")  -^é^'K  ^c.  in  the 
order  in  which  they  occur  in  [4904]  ;  and,  noticing  also  the  terms  [4923Ar,  y],  depending 
on  the  angle    2^w — cv. 

First.  The  first  line  of  [4904]  gives  k  =  J.f\  i=2—2m;  substituting  this  in 
[4923r],  it  becomes,  {2—2m).A.i''K\k'.cos.{[2—2m\omv')—k'.cos.{2v—2mv-\-v')\. 
The  first  line  of  [4885],  neglecting  e^,  gives  A:'=  1 — ^e'^,  v'=2u — 2mv;  substituting 
these  in  the  first  term  of  [4924c],  we  get  the  first  line  of  [492.5]  ;  the  other  term  of 
[4924c]  depends  on  the  angle  (Av — 4;nu),  which  is  neglected.  In  like  manner,  the 
second  line  of  [4885],  gives  k'^ — 2(l-)-m).(l — |e'2).e;  v'=  2;; — 2mv — cv  ;  hence, 
the  first  terra  of  [4924c]  becomes, 

—{2—2m).Ai''\2[\+m).{\—y).e.cos.cv=—A{\+m).\{\—m)Jl.p.{\—^e'^).e.cos.cv\; 
and,  by  the  same  process,  we  get,  from  the  third  line  of  [48S5],  by  using  the  factor   1 — Je'^ 

VOL.  III.  109 


[4926'] 
[4923t] 
[4923u] 

[4923w] 

[4923u>] 

[4923x] 

[4923j,l 

[4923:] 
[4924o] 


[49246] 


[4924c] 
[4924<i] 


[4924e] 
[4924/] 


434 


THEORY  OF  THE  MOON 


[Méc.  Ct 


[4927] 


—  - — -.\3.sia.(v — m  r) +15.  sin.  (3 1) — 3m.v)l.- 


8a,a' 


civ 


[4924^] 

[4924i] 
[4924*] 

[4924?] 

[4924m] 

[4924nl 
[4924o] 

[4924j>] 

[4924?] 
[4924r] 

[4924«] 

[4924<] 
[4924<'] 


[4S79)t],  the  term  — 4(1 — m).\{l — m).A.}°\{l — Je'^).e.cos.cy} .  The  sum  of  tliese  two 
terms  is  — 8|(1 — m).Jl2^°\{l — ^e'^).e.cos.cv],  as  in  the  second  hne  of  [49'25].  It  is 
unnecessary,  in  this  case,  to  notice  the  second  term  of  [49:24c],  because  tlie  coefficient  of  v 
is  so  large,  that  the  term  becomes  insensible.  Proceeding  in  the  same  manner  with  the 
fourth  line  of  [4885],  which  gives  A:'=J«',  v'=2v — 2mv — c'mv  ;  also,  with  tlie  fifth 
line  of  [4885],  which  gives  k'^ — ie',  v'=^2v — 2mv-\-c'mv,  we  find,  that  the  terms 
corresponding  to  the  first  of  the  functions  [49'24c],  are,  respectively, 

-\-{2— 2in). A2^^\^e'. COS. c'mv,  —  {2— 2m). A^^^lie'. cos. c'mv  ; 

whose  sum  is  6.(1 — in)  .  ^n"'.  e'.cos.c'm  v,     as  in  [4925]  line  4. 

The  remaining  terms  of  the  function  [4S85],  being  of  the  seco?u/  or  higher  orders  in  e, 
e',  7,  multiplied  by  Wt  of  the  second  order,  and  ^o""  of  the  second  order,  produce  only 
terms  of  the  sixth  and  higher  orders,  which  may  be  neglected. 

Second.      The    second    line  of  [4904]   gives     Ar=.^/".e,      i^2 — 2m — c,     hence 
[4923^]  becomes, 

(2—2m—c).A^'^\e.\lc'.cos.{[2—2m—c]  VMv')—'k'.cos.{2v—2mv—cv-^v')  \ . 
Substituting,  in  the  first  term  of  this  function,  the  values  [4924f/],  corresponding  to  the  first 
line  of  [4885],  we  get  the  term  (2 — 2n — c)Jl^''>.r.{l — |Ê'^).cos.cit,  as  in  the  second  line 
of  [4925].  The  second  and  third  lines  of  [4S85],  produce  terms  having  the  factor 
A[''.m.e^,  of  the  fifth  order;  but  they  do  not  increase  by  integration,  and  are  therefore 
neglected.  The  fourth  and  fifth  lines  of  [4835]  correspond  to  the  values  [4924A],  and  by 
substituting  them  in  the  first  term  of  [4924/],  we  get  the  two  terms, 

ie'.{2—2ni—c).J['''.i    .cos. {cv— c'mv),     —ie'.{2—2m—c).â['Ke.cos.{cv+cmv), 
as  in  [4925]lines  6,  5.      All  the  remaining  terms  of  [4885],  excepting  that  in  line  12,  ma}' 
be  neglected  as  in  [4924A:].  This  line  corresponds  to   ^"':= — i(2-j-m).y^,  v'^=2gv-2v-J[-2mv, 
and  produces,  by  means  of  the  second  term  [4924/],  the  expression, 

+i{2-{-m).{2—2m—c).A^'\ey^.cos.{2gv—cv). 
Connecting  this   with    tlie  terms,  between   the   braces   in    [4923^,  q],  depending   on    A';'\ 
they  become     \g-\-m-{-l{2-\-m).(2 — 2m — c)l.A['Ke-)'^.cos.{2gv — cv)  :    and,  as  c  is  nearly 
equal  to   1,  we  may,  by  neglecting   m^,  put    jm.(2 — 2m — c)=:.^m;    consequently,  the  first 


-c)+]^  =  i{4g  +  4-}-m-2c) 


factor  of  the  expression   becomes,      ^-i-'«+f(2 — 2;«- 
which  is  the  same  as  the  coefficient  of  A'l\  in  [4925]  line  9. 

Third.  The  term  Jlf\e.cos.{2v—2mv-]-cu)  [4904], combined  with  [4885]  line  1,  gives 
the  term  depending  on  .^2'-'  [4925]  line  2.  In  like  manner,  we  may  combine  the  terms 
of  [4904],  depending  on  ^.P\  A"')  ^^'tli  ''^e  same  terms  of  [4885],  to  obtain  the  terms 
depending  on  Ai'^\  A^''^  [4925]  line  4  ;  observing,  that,  as  c'  is  nearly  equal  to  1,  we  have 
very  nearly  2 — 2m-\-c'm.=:2 — m,  2 — 2m — c'm=2 — 3m.  The  term  depending  on  ^j^^' 
produces  nothing  of  importance. 


VII.  i.  §  8.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  435 

*hence,  wc  obtain  the  quantity,  [4927'] 


Fourth.     The  term  depending  on  ^f    [4904]  gives    k^Af^ce',    i=2 — 2m — c-\-cm , 
or  nearly    t=2 — m — c.     Substituting  tiiis  in  [49232]  it  becomes,  ^        "' 

(-2 — 7n—c).ji'°\ec'.\f<f.cos.([2—2/)i — c-\-c'm]  v  r» v') — A;'.cos.(2« — 2mv—cv+c'mv-{-v')l.        [4924i)] 
The  first  line  of  [48S5]   produces,  in  the  first  term  of  [4924y],  the  quantity  depending  on 
.4'''  [49-25]  hne  6  ;  and  the  fifth  hne  of  [4885],  produces  the  terms  depending  on  Jl['^\  in 
Une  3  [4925].     In  like  manner,  the  term  depending  on  A'-p  [4904],  combined  with  [4885]  "'' 

lines  1,4,  produce  tliose  in  [4925]  lines  5,2,  depending  on  A'-p.     Also,  the  terms  depending 
on     Af\     A'p    [4901],   being  combined   with    the   first  term    of   [4885],    produce    the    [4925a] 
corresponding  terms  in  [4925],  lines  8,7. 

Fifth.     The  terms  of  [4904]  depending  on    ^2<"»,   ^;"\    Ai''^\     produce   nothing    of 
importance.     The  terra  in    line   14   [4904],  gives    k  =  A[^^>.y^;     i  =  2g—2+2m^2m    [4925t] 
nearly;    and  the  first  term    of  line   2   [4885],  gives      ]i'= — 2e,      v'^2v — 2mv — cv. 
Substituting  these  in  the  second  term  of  [4923:r],  it  produces    4m.C7'^.^,"3'.  cos.(2^t' — cv).     [4925c] 
Connecting  this  witii  tlie  second  term  of  [4923/c],  we  obtain  -2(l-2m).A[^^''.ey^.cos.{2gv-cv),    Mg^Sj^i 
as  in  [4925]  line  9.  The  term  depending  on  -^a^'^'.e'^  [4904]  produces  nothing  of  importance. 

Sixth.     The  term  in  [4904]  line  16,  gives  k=A^-^^Key^,  i=2g—c=l   nearly;  and  the     [4925e] 
first  term  of  [4835]  line  1,  makes    k'=l,    v'—2v—2mv  ;    hence,  the  first  term  of  [49232]    [4925/] 
produces     ^„'''''.  e7^.cos.(2v — 2mv — 2gv-\-cv),    as  in  [4925]  line  11.     The  same  values  of 
]c',    v',    being  combined  with  the  term  in   [4904]  line  17,  produce 

(^2—2m—2g+c).AP'^\ey\cos.{2gv—cv),    as  in  [492.5]  line  10.  [4925g] 

Seventh.     From  [4904]  line  18,  we  have    k  =  A["\-,     i=l — m.      Combining  these 

[4925A] 
with   k',  v'  [4925/],    we  get  the  term     {l—m).J["\-.cos.{v—mv)      [4925]  line  12.     If 

we  combine  the  same  values  of  k,  i,  with  the  term  in  line  4   [4885],  we   get   the  term    rjqor-i 
depending  on  A^'''     [4925]  line  14  ;  and  if  we  combine  them  with  that  in  line  5  [4885],  we 
obtain  the  term  depending  on    A^p\  in    [4925]  line  13. 

Eighth.     From  [4904]  line  19,  we  have   k=  A^^^\-,.e',     i  =  \ — m-^c'm=l    nearly. 

Combining  this  with    k',    v'    [4925/J,  we  get  the  term  depending  on  ./îo"*'  [4925]  line  14.    [4925t] 

If  we  combine   these  values  of   k,   i,    with  the  term  in  [4885]  line  5,   we  get  the  term 

depending  on    A'^^''>  [4925]  line  12. 

JVinth.     From  [49041  line  20,  we  have    fc=./3P\-,.e',    i=  1— ?«— c'ot=1— 27«  nearly. 

"•  ^  "      a'    '  •'      [4925/] 

Combiningthis  with  the  values  yt',  v'[4925/'],we  get  the  terms  depending  on  ./3,"'' [4925]  line  13. 

Tejith.     The  term  of  a (5m  [4912],  gives    k=\.-,i^3 — 3m.     Combining  this  with    r^^^Sm] 
the  values  [4925/],  we  obtain  the  term  depending  on  Xn,   in  [4925]  hne  12. 

Thus,  we  have  obtained  all  the  terms  of  the  function  [4925],  as  they  are  given  by  the 
author  ;  and,  it  is  evident,  from  the  details  of  the  calculation  in  this  note,  that,  in  general,    [4925n] 
the  neglected  terms  are  such  as  have  been  usually  rejected. 

*  (2825)      Having    found,  in  the   preceding  note,  the   variation    of   the  first  term    of 


[4928] 


*  2 

9/« 


436  THEORY  OF  THE  MOON  ;  [Méc.  Ce). 

2 

9  »"  1  N         Jim     "  ^  \ 

-;; —  .  (  1 m)  .^'"'  .-.COS.fv — OT  V). 

4o,      ^  "^     a  ^  ^ 

(  7  )  ■  Z^^iv  '     '^°"'*'"^'^  '"  [4876],  we  shall  now  proceed  to  the  calculation  of  the  next 
■  temi,  which  is  given  in  [4860]  ;  and,  if  we  put,  for  brevity, 

t'*^^^"]  A=—  ^^.|3.sin.(t>— t,')-f  15.sin,(3y— 3i;')}; 

this  part  becomes     ^.  — .  Its  variation,  considering  u,  du,  v',  as  variable,  and  neglecting  i5m', 

[49276]     as  in  [4909, fee],  is       ('L^]  ^  ^^^/l'    ,    f^)     s,'    ^a  ■  ^     ^ 

\  du  J  dv     '~  \  dv'  J  '       '   dv  '    dv    ' 

The  factor     ^^.     in   the  value  of  A  [4927rt],  is  of  the  order     iïi.-  .  -,      [4921  è], 

[4927c]     which  is  of  the /oMrtA  order  ;  therefore,    (-r-j,    (-p)    are  of  the  same  order.     Moreover, 

5m  [4904]  is  of  the  «cconrf  order  ;    —   [4878]  is  of  the^îr^i  order;  Sv'  is  of  the  third  order 

[4916,4917];  consequently,       (-—  ).(5m.  —     is  of  the  ici'OiiA  order;  and  (—].Sv'. — 

V  ait  /  du  \  dv/  dv 

of  the  eighth  order  ;  so  that,  by  rejecting  these  terms,  the  function  [4927i]  is  reduced  to 
A. --7-  of  the  sixth  order.  Then,  by  neglecting  terms  of  the  seventh  order,  we  may  use 
in  A  [4927a],  the  values  [4921a — c],  and  the  preceding  expression  becomes  as  in  [4927]. 

*  (2826)     The  differential  of  [4904],  divided  by  dv,  gives, 
-^^  =— (2— 2m).^i''\sin.(2i;— 2mt)) 

— (2— 2m— c) ../?/".  e .  sin.(2u— 2mM— cy)  —  &c.  ; 

which  is  to  be  substituted  in  [4927].  In  the  first  place,  the  terms  depending'on  .^o""  [4928a], 
produce,  in  [4927],  the  following  expression  ; 

[49286]  5"^'-(2 — 2m)..^o°\{3.sin.(t) — M«)-]-15.sin.(3i; — 3mt>)  |.sin.(2t) — 2mr)). 

As  this  is  of  the  sixth  order,  we  need  only  notice  the  resulting  terms  which  depend  on  the 
angle  (y — mo).     Now, 

3.sin.(t) — mr).sin.(2u — 2mu)  =^.cos.(i' — mv)  —  kc.  ; 
15.sin.(3y — 3mw).sin.(2u — 2my)^-L5-.cos.(4) — mv) — Sic.; 
whose  sum  is  9.cos.(« — m«)  —  Sic; 

hence,  it  is  evident,  that  the  term  [4928i]  is  equal  to 

[4928c]  ^^.(2— 2m).^2<''i.9.cos.(D— mu)  ; 


[4927d] 


[4928a] 


VII.  i.  •§.  3  ]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  437 

The  function  [4891], 

contains,  in  the  first  place,  the  term, 

-  (S  +  ")  •  /  ^^  •  ^•"-  (2  «-2  «')      [4882]  ;  [4930] 

its  variation  is,* 


which  is  easily  reduced  to  the  form  [4928] .  We  may  proceed  in  the  same  manner  with  the 
terms  of  «(5it  [4901],  deiiendins  on  /7'j".c,  Jl:?\c,  &ic.  ;  but,  as  these  terms  produce  only 
cjuantiiie?  of  the  sixth,  seventh,  &ic.  orders,  they  may  be  neglected. 

*  (2827)     We  shall  put,  for  brevity, 

V=~+u,  JV='-'i^.sm.(2v—2v');  [4929a] 

then,  we  shall  have  the  development  of  F',  in  the  second  member  of  [4890]  ;  and  the 
expression  [4930]  will  become  — V.fW.dv.  Now,  as  V,  W,  contain  the  variable 
quantities   u,  u' ,  v ,  the  variation  of  the  function  — V.fW.dv,  will  be  denoted  by 

—  ^^■■fl  O  ■'^"  +  (?)•''"'  \  .dv~5V.fJ'V.dv—  V.f(^-£).âu'.dv.  [49296] 

The  three  different  integrals,  of  which  this  expression  is  composed,  correspond  respectively 
to  the  three  integrals  in  [4931],  as  we  shall  find  by  the  following  investigation  ;  in  which  we 
shall  U5e  the  abridged  notation  [4821/]. 

If  we  substitute  the  values  of    (y-j,     (yr))  deduced  from  that  of  JV  [4929a],  in  the 
first  of  thc^  integrals  [4929'],  it  becomes, 

-^•'^K^}'"+(^j-'"T''"=-i:^-/-,7r- J  -•^'"•(2«-2''')+|5«'-cos.(2t;-2«')^  ;      [4929c] 

in  which  the  terms  under  the  sign  /,  are  the  same  as  in  the  first  term  of  [4931].  If  we 
substitute  the  values  of  c,  g  [482Se],  in  V  [4890],  and  neglect  terms  of  the  order  m% 
m^'r,  e^  iA  we  obtain,  ['•^29^] 

V=-^.ll-^^f.C0S.'2gv].  [4929e] 

Substituting  this  in  the  factor,  without  the  sign  /  [4929c],  it  becomes  as  in  the  first  term  of 
[4931].  As  the  terms  of  nôu  [4904],  are  of  the  second  or  higher  orders,  it  follows,  from 
[4908°-].  that  the  terms  depending  on  Su,  under  the  sign  /  [4939c],  are  of  the  fourth  or 
higher  orders  ;  and  when  these  are  multiplied  by  the  terms  of  V,  which  we  have  neglected  [4929/] 
m  [4929f/],  they  will  produce  only  terms  of  the  siith  or  seventh  orders.  Those  of  the  sixth 
VOL.  II[.  110 


438  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

^^'"'  '  1+f / ^-008.(2^^-2 Oj./—,-  .  5 -.si.i.(2«— 2i;')-|-èV.cos.(2o— 2i0?i 

U  f  It  J 


h^a 


r,.r,oii  /(hUu     ,  \  .Zm'.u'^.fh       .       ,r,  o    '\ 

[4931]  —  (  _f  oM  \  .  f  —       — .sin.(2i'— 2t7'_) 


rr-  .  /  ■ .dv.s\n.(2v — 2v).  * 


order  are  produced  by  c^.  ^  ^-  ['IGSOc/],  and  do  not  depend  on  the  angles  v — m  i\  and 
'\lgv — CD,  whose  coeflicients  are  required  to  a  great  degree  of  accuracy;  hence,  we  see  the 
propriety  of  neglecting  the  above-mentioned  terms  of  V  [49ii9(/]. 

In   making  this  estimate,  we  have  omitted  the  consideration  of  hv'  [4929c],  because  it  is 
[4929g-]    of  the  order  tn.aou  [491G,  4917],  and  must,  therefore,  produce  terras  of  still  less  importance 
than  those  of  «<3m,  which  we  have  neglected. 

Again,  the  value  of  J^  [4929«]   gives     5V='-—--\-&u;  substituting  this  in —(SP'.//r.rfw 

[4929i],  it  becomes  as  in  [4931]  line  2. 

Lastly,  taking  the  partial  di.Terentlal  of  ÏV  [4929fl],  relative  to  m',  and  substituting  it  in 
the  third  integral  [49296] ,  it  becomes , 

Now,  from  [4833],  we  have  nearly,  a' a'  =  e'.coscv'^^  whose  variation  is, 

a'&u'  =  —  c' e'.  (]v'.  sin.  c'  v'  ; 
and,  as  6v'  is  of  the  order  m.ahi   [4929j],  this  quantity  will  be  of  the  order  me'. a  Su.  or  of 
[4929fc]    the  fourth  order  [4904].     If  we  retain  only  the  chief  term  of  [4929e],  we  get     V=  - 

and,  by  using  the  value  [4921i,&.c.],  we  find,  that      --—      is  of  the  order 

[4929Z]  ^^^  •  a  a'  —m  .a  a'     [4865]  ; 


[4929t'] 


V.  f  (^~\ .  Su!,  de  =  —V.f  ^-^ .  Su'.dv  sin. (2«— 2u'). 


consequently,  the  function  [4923/]  is  of  the  sixth  order  ;  and,  by  neglecting  terms  of  the 
seventh  order,  we  may  subnltute  the  value  of  V  [4929;.],  in  [4929J]  ;  by  which  means  it 
becomes  as  in  third  line  of  [4931]. 

*  (2828)  In  computing  the  value  of  the  function  [4931],  we  shall  retain  termsof  the  fifth 
[4931o]  order  in  e,  e',  y,  (V);  also,  in  the  coefficient  of  cos.cv,  we  shall  retain  the  factor  l—^e'^. 
[49316]    In  the  terms  depending  on  the  angles   '2gv—cv,   v—mv,  v—mv±c'mv,  we  shall  retain  terms 


VII.  i.  §8]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  439 

The     development     of   these    terms,    observing,    that     c     is  nearly    equal      [4932] 


of  the  sixth  order  ;  observing,  that  the  divisors,  arising  from  the  integration,  2§* — 2-|-2m, 
2c — 2-(-2m,  which  occur  in  the  terms  depending  on  -^3'"',  -^j,"'*'  [4934],  are  of  the 
order  m  ;  so  that,  independent  of  these  divisors,  these  terms  must  be  taken  to  include 
quantities  of  the  sixth  order. 

We  shall  first  compute  the  term 
12  ni' 


./iq;l".^.sin.(2.-2.')      [4931]. 


To  obtain  this,  we  shall  take  the  differential  of  the  equation  [4885],  and  then  multiply  it  by 

2 

-,     neglecting  such  terms  as  we  have  usually  done,  and  using  the  abridged   notation 

[4821/]  ;  hence  we  get, 


[4931c] 
[4931rf] 

[4931e] 
[4931/] 


6  m' 


2— .sm.(2« — 2v)  =^ .dv. 


^(1— I  e'2).sin.(2t)— 2m«) 
— 2(l+w).(l — Je'2).e.sin.(2«— 2mt)— cr) 
— 2(1— m).(l— Je'2).e.sin.(2D— 2mt;+ci') 
-|-Je'.sin.(2« — 2m  j) — c'mv) 
I  — i  d .  sin.  (2  v — 2  m  v-\-c'm  v) 
\ — J  (2-|-37n)  .ee'.sin.(2D — Imv — cv — (imv)\ 

-^  (2 — 3m)  .ee'.sin.(2t) — 2mv-\-cv — c'mv) 
~\-l  (2+m)  .ee'.sin.(2v — 2mv — cv-{-c'mv) 
\~\'i  (2 — m)  .ee'.sin.(2« — 2mv-\-cv-\-c'mv) 
I_|(104-19m).e2.sin.(2cj)— 2«+2mr) 
+i(10— 19m).e2.sin.(2ct!+2t)— 2?n?;) 
— ^  (2-fm) .  7=.sin.(2^tJ— 2  y+  2m  v) 
-f-î(2 — m)  .^-.sin.(2^«-|-2D — 2mv) 
4-^^-.e'^.sin.  (2v — 2mv — 2c'mv) 
\ — 1  (5-{-m) .  e 7^. sin. (2 v — 2  m  v — 2gv-\-c v) 


1 
2 
3 

4 

5 

6 

7 

8 

9 

10 

11 

|l2 

1 13 

14 

15 


This  is  to  be  multiplied  by  the  expression  of    -     [4884] ,  to  obtain  the  value  of  the  function 

in  the  first  member  of  [4931fc].      By  this  means,  the  product  of  the  factors,  without  the 
braces,  becomes. 


a 
12  7n 


dv,     as  in  [4931  A:]  ; 


and  the  products  of  the  terms,  between  the  braces,  are  found  as  in  the  following  table  ;  in 
which,  the  first  column  contains  the  terms  of  [4884]  ;  the  second,  those  of  [4931^]  ;  and  the 
third,  those  of  [4931A:],  respectively  ; 


[4931g] 


[493U] 


440  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4933]     to    1  —  fm^     and,  that    g     is  very  nearly  equal  to     \-\-^m^     [4828e],  is, 


[4931t] 


[493U] 


(C..1.3.) 
Products,  or  terras  of  [49314]. 

whole  function  [4931^]  between  the  braces 

.  .  .  .neglected 

— J-e.(l— |e'a).  \  sin.(2y— 2H;u-(-a))+sin.(2i)— 2mi;— «>)  \ 

-(l+«i).t2.sin.(2cD— 2î)4-2nu))-l-&c. 

-|-(1 — în).c2.sin  (2cî)-j-2i) — 2inv) — &c. 

— j-ec'.Jsin.(2u — 2«iD-|-fi;— cm«)-|-sin.(2i)— 2mti — cv — c'mv)\ 

-\-iee'Asm.[2v—'imv-\-cv-\-c'mvY\-sm.[2v — 2mv—cv-\-c'mv)\ 

.  .  .  .neglected 

-)-J-c2.|sin.(2cu-(-2v— 2mD)— sin.(2cu— 2«+2mu)| 

-|-gL>2.{sin.(2g'i)+2u— 2mw)— sin.(2g-u— 2i;-t-2mD)} 

— jfi  2.(i_j_,„jsin_(2j, — 2mD-|-2g-i- — cv) — &,c. 

—  je}2.(l — Hi).sin.(2« — 2niv — 2gv-\-cv) — &c. 

Substituting,  in  the  third  column  of  this  table,  the  value  of  its  first  hne,  which  is  equal  to  the 
terms  between  the  braces  in  [4931^]  ;  and  then  connecting  together  the  terms  of  tiie  same 
forms,  it  becomes  equal  to  the  terms  between  the  braces  in  the  second  member  of  [4931  A:]  ; 
and  the  external  factor  is  as  in  [4931A]  ;  hence  we  get.  by  retaining  terms  of  the  usual  forms 
and  orders, 


(Col.  1.) 

(Col.  a.) 

Terms  of  [4884]. 

Terms  of  [4931f  J. 

1 

whole  of  [4931g-] 

-y^-if 

same 

— e.cos.cw 

(l_|e'a).sin.(2r— 2mi>) 

-2(l+m)f.sin(2v-2Hit)-a') 

-2(1-7)1  )e.sin{2iJ-2nn;  +  cii) 

4-Je'.sin  {2v—2mv—c'mv 

—  4e'.sin.(2D— 2;)iD-[-c'mD; 

-c{-^e2-i72)cos.«) 

whole  of  [4931g-] 

-\-^e'^.cos.2cv 

-t-sin.(2y-2mD) 

+ly,Kcos.2gv 

-(-sin.(2t)— 2m») 

-2(  14-)n)e.sin(2i)-2mv-CD) 

-2(l-m)e.sin(2D-2nn)-|-cv) 

12)ra'  u'Hv  1    .     ,^       „  ,,       12m     , 
7r-5  •-^-•-•sin.(2» — 2v  )= .  dv. 


(1— Je'2).sin.(2«— Smt)) 
— (t+2ff?)  (1 — fe'^).e.sin.(2« — 2mv — cv) 
—{i—2m).{l—he~).e.sm.{2v—2mv-{-cv) 
-|- Je'. sin  {2v — 2mv — c'wd) 
— 2  e'.sin.(2» — 2mv-^c'mv) 
— f  (|-|-3/n).ee'.sin.(2« — 2mv — cv — c'mv) 
— i  (I — 3  m)- e  e'.  sin.  (2  v — 2  m  v-j-c  v — c'm  v) 
\  _j-i(A-[-m).eÉ'.sin.(2  Î) — 2  jn  v — cv-\-c'mv)    f 
-)-^(J — jn).ee.im.{2  v — 2mv-\-c  v-\-c'm  v) 
—l{\5-\-2^m).e^.im.{2cv—2v-\-2mv) 
J^l{\b—23in).e^.sm.{2cv-\-2v—2mv) 
— {{h-\-m).y^.sm\2gv—2v-\-2mv) 
-\-l{h — m)  7^.sin.(2^t)-|-2y — 2  mv) 
-}-y-  e'^.  sin. (2  v — 2  m  v — 2  c'm  v) 


1 

2 
3 
4 
5 

6 
7 
8 
9 

10 
11 
12 
13 
14 


[49311] 


This  is  to  be  multiplied  by    a&u  [4904],  and  then  integrated,  to  obtain  the  value  of  the  term 
[4931e].      Now,  if  we  suppose  any  term  of  aiu   to  be   represented,  as  in  [49l8i],  by 

a<5u=A:.cos.iu  ;     and  any  term  of  the  second  member  of  [4931fcJ,  by  .dv.Icsm.i'v  ; 


VII.i.§S.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  m-I        441 


3  M 


4«,.(1 — m) 


{4.(1— m)^— 1  l.A°\(l—ie'^) 


Z_!!L)     4.(1— m)  '       <     V         IS   l2-2,n~c   '  2-2H^-[-c3      ~     >.c(l-Je'»). 


6m 

n. 


+  ^ 


{4J/'+J/'-4'^'-10^/'>e=+|(J/^-J/^'.).6^ 

_  —  .  (  4  .  1— ,«  —1     ..Jf'.  ]  — — -  —    S 

^^      .if2=;,'_l\^(3)4.('ôi:3;^'_l\^(4) 


4a,.(l — m) 

3  w 
a. 


>.e'.cos.(c'm«; — to') 


"*■    '        .e  e'.cos.(2  « — 2mv — cv — c'mw+is-(-TO') 
ee'.cos.(2t) — 2m  a; — c«+c'?«u+w — -n') 


a,.(2— 3  m— c) 

o 


2 

cos(cu-w) 

3 


4 
6 
6 


[4934] 


a,.(2 — m — c) 


Bevelop- 

7      nient  of 
the  varia- 
tion(4931). 


8 
9 


the  product  of  these  two  terms  will  be  represented  by 

.dvJck'.  \  sin.(i't) — i  v)  -\-sm.{i'v-\-iv') 

Its  integral  gives  the  corresponding  term  of  [4931c]  ;  namely, 


[4931m] 


l'2m'      u's.rfc    ill    .  Chi      C         kk'  .,         .  kk'  /•/     ■   •    \> 

"Ai^--^"lir----^'"-(2^— 2?')=— •  J— ^Tr^.-cos.(ii;— It))— — .cos.(it)  +  ii;)  J;        [4931n] 

all  of  which  have  the  common  factor     ,     and  the  terms  between   the  braces  ;    namely, 

kk'  k  k' 

— T7-:-cos.(J'y — iv) — ^r--cos.{i'v-\-iv),     are  computed  in   the  following  table;    in  which,     [4931o] 

the  first  column  represents  the  terms  of  a  5m  ;  the  second,  the  terms  of  [4931^];  and  the  third, 

the  terms  of  the  function  [4931o]  :    the  operation  being  performed  for  each  term  separately, 

putting  c  and  g  equal  to  unity,  in  several  of  the  small  coefficients.     When  i'  =  i,  the  first 

term    of    [4931m]    vanishes,    and  the   function    [493 1  o]   is  reduced   to    its  second    term 

kk' 

.cos.Sii,'.     This  case  occurs  in  the  first  line  of  [493I7j1,  which  is  reduced  to  a  term,    [4931o'] 

2i 

depending  on  the  angle     4v — 4my,     that  may  be  neglected. 

VOL.   III.  Ill 


442 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4934] 

Continued* 


2 

6  vi 
a^.[c — 7Ji)' 


{^f +J  J,'"] .  ec'.cos.(c?;— cVtt  I'— ro+T^i') 


10 


Develop- 
ment of 
tlie  first 
term  of 
the  func- 
Uon[4931]. 


[4931;?] 


(Col.  1.)     Terms  o(  aôu  [4904]. 


Ji^  ' .e.co3.(2v—^mv — cv) 


A  ^   Ke'.co9.(2y — ^mv-\-dmv) 
A  ^   '.e'.cos.{2i; — ?mi' — cmx) 

^j   .ee'.cos.CSw— 2m«— cv-t-cwii') 


A  ^"^.ee'.cog.CSu— 2fflw— cw— c'nitJ) 


A  ^     .ec'.co3.(cr4-c'wip) 
A  ^     .ee'.co3.(ci* — c'twv) 

^  f '^'.c".co3.(2cîî— 2«-i-2mr) 

^(13)  ,j2  ^.^g_^3^„_Oy_j_nn[v) 

a  (14)   g—  gpg  Oc'my 
2 


__  ^'^^e>**.cu3.(2^v— cr) 

^  f '^\c>~.cos.C:!u— 9/nu— 2uru-f-cv) 


^l'^\",.C03.(i'-Jni.) 
1        a 


^  '  ^^ ,  -  .e'.co3.(u — ïnî)-j-c'mu) 
0        a' 


(19)  a 
X  ,-.co3.(3u — 3mtJ) 


(Col.  2.)     Termg  of  [493JA]. 
A— l-.c'-Vsin.Coy— 2011)) 


second  term 
third  term 


-t-^.c'.sin.(2u — 2mw — c'mv) 
^X.e  .sin.(2« — 2mv-|-c'ffiv) 

/'l_|..c'^Vsin.(2o— 2mv) 
-|-X.e'.3in.(2u — 9m  I' — c'mr) 
^X.e'.3in.(*3ii — 2mi;-|-c';nu) 


4-^.ec'.sin.(2a — 9mw — cw-l-c'm«) 

— |. /|.-|- m)  .■),^.sin  .(2«^>— 2u-f-2mv) 

(\ — A.c    }.sin.('2« — 2jnu) 

sin. (2)1 — 2hi«) 

8in.(2i; — '^mv) 

sin.(2u — 2mt5) 

sin.(2H — 2mzj) 

^i.  e  .  sin.(2(' — 2H(y — ce) 

^_l..e'.sin.{2u — 2;rty-|-c'nn)) 

Rin.(2u — 2fflv) 


-|-l..e^.sin.(2t'— 2mu— c  my) 

3in.(2u — 2m(,') 

sin.(2y— 2Hiy) 

8in.(2y — 'imv') 

sin.(2u — 2ïnu) 

sin.(2y — 2/hu) 

^A.e.9in.(3u — 2)nw — cy) 

[terms  of  41)3IA] 

8in.(2y — 2my) 

Bin.(9u — 2my) 

3in.(0]' — 2»ni) 
-[-- Z..e'.sin.(2y — 2m  y — c'my) 

^X.e'.sin.(-3(5 — 2mu-|^'ïnu) 

sin.(2« — 2mi') 

^-l-.e.sin.(2u — 2wu-j-c'mp) 

sin.(2ïi — Omy) 
sin.(2y — 2my) 


(Col.  3.)      Factors  of      ^^^      [493l7i]. 
.  .  .  .neglected 

+|.^<°'.^,.c,„.c'„,» 

4"4-'*^0      •-  .C05.C'7ffU 

-Jj(').e.(:_|.e2|eo3.c«   ' 

7     fl(l)     «C  ,  ,      . 

— -2-^j  '.^-3;^.COS.(ci:— c'ïniO 

+4-'*^,     •— r-  .cns.(cr'4-c'7ni') 
^       ]      (■-t""ï 

~~-r'rl       ', .COS.C/BV 

*         1  )« 

_5     ^(M   e^f' 

^j--*^     '.  .C0S.C7WU 

(+|-+l.'»)..4^j'^.É>°.cos.(2û^y— cy) 
+^^~^.c.Ci— A.c^^.cos.cy 
+.4^'  '  S-  .C09. c'/nu 
— -ï  '      .-  .cos.f  j/iy 
.  .  .neglected 


—  A  jî'      .^^ — ^  .cos.c'?«i? 

I   1    _^(6).«c'^.cos.cw 
^2"     1 

^^^f^)  ,_^^  .co3.(cîî-|-e'mv) 
1      r-j-/i/ 


+4-^' 


û).'- 


—l-.A 


1 


1      2-3'»-c 
(9)        gg' 
•*1     "a-m-c 

«(10). 


..co3.(2y — 2mi'— CI! — c'mu) 
.co9.(9« — '^mv — cy-f-c'mu) 
.  .cos.(2cv— 2y+9mi') 


"2        9C-2+2/I 
.  .  .  .neglected 

Jf-A^  '-\ ^  '       .cos.  (2;fv— 2u4-27nr) 

-f-A.^j'3)/.j2c^s.(2^î)— cu) 

.  .  .  .neglected 


All  thpse  N 

terrnshiive  J 

I    the  fcim-    f 

mon  factor  ^ 


-Jt 


(13) 

"0    "s-a»! 


.79 


..COS.  (aï— 2mf— S^'-|-c!)) 


— .>?(  ^  .€ y^.cos.  (2^u — cu) 


J  17)  5       1 


— .y?  ■  '/^^  ^_^ — .cos.fv — Tnu) 
«     1  —  m 

2       1 

■^o^'-S'Trsr,,;'^"''-^''""''-'^'""') 

ia(18)a         c'a 


.^  .cos.(t' — my — c'mv) 
a' 

.e'.'i  .cos.(i' — mu+c'my) 


~«('0!.'i,..<-m.(,._, 


('• — ïttr-f-c'mu) 


+^5-S'TÎ;:-=°'-("-'"'')- 


3 
4 
5 

6 

7 

8 

9 
10 

II 
12 
13 
14 
15 
16 
17 
18 
19 
20 
21 
22 
23 
24 
25 
96 
27 
28 
29 
30 
31 
33 
33 
34 
35 
36 
37 


V1I.1.§8.J    DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  443 


^"'      _^jP)_ijo)l,ee'.cos.(cv+c'7nv—-^—^')  11 


a^.{c-{-m) 

2 

_2  [4934] 

H !'""l"'l  X  -r-  cos.(2o-t^— 2«+2OTt>— 20  13    cu„.inuc,i. 

a,.(25-— 2+2/n)    '  ^    *  '  ^ 

+  ^.^5  2J','=''-J[«"+^.4"i.e^^.cos.(2^r— ci'-2é+^)  14 

«,  8 

2 
fi  -      ^(15)  Continua. 

—  ,,     ;      . ,.ef-.cos.(2v—2mv—2gv+cv+2ê—v^)  15    .rdfvei- 

'  ^  '^    '      '  •  Ihe  func- 

2  tion[4931J. 

—  .  ^/r    ,.?a+3tfO-4"^— 24"'-e'-— l.[l— (1— m)n.x,].-,  cos.(î;— m«)  16 

+  ^.M'/')  — 2  4'^)}.-.e'.cos.(y— miJ+c'mî;— t.')  17 

a,      '     '  '     ^   a'  ^ 


We  may  remark,  that  the  sum  of  the  terms  in  lines  2,  3,  is  reduced  to 


4m. (I ^e'-).^fe.COS.CV;  (38)      continued. 

the  sum  of  tiiose,  in  lines  4,  5,  to     4^'2?.-.cos.c'/««  ;     and  the  sum  of  those,  in  lines  9,  10, 

"    m 

e9e'  .  ''"' 

to      —10.^/"'. — .  cos.  c'm  r.     Moreover,   the  term    neglected    in    line    25,  of  the    form 

m 
e2 
— -(4/"\-— .cos.(2c!; — 2n),      will  be  used  hereafter  in  a  different  calculation  ;  also,  the  term    [AdiXq] 

2 

i.^/".e2.cos.2cy,     arising  from  the  combination  of  [4904]  linel,  with  the  first  term  in    [493ir] 

line  3  [493  iq. 

The   function   [4931^]  is  also  multiplied  by     ^y^.cos.{2gv — 2é),     in  [4931];  but  the 
only  term  of  [4931p],  which  requires  any  notice,  is    —  ^y\e.cos.ct),   in  line  6  ;    because  the    r493j,i 
product  of  these  two  terms  produces  a  quantity,  depending  on  the  angle     'igv — cv,     of  the     ugsj^i 
following  form  ; 

°  '  SeconrJ 

o  term  of 

-^-.|f  .cos.(2^,;-2J)./  !^  .  —  .sin.  (2.-2.')=-  — •  \\.'Ai'\ef.cos.{2gv-cv)\-    -"H»n 
''^a  -^       «''         «  a,      <-«  )      [4931«] 


444  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4935]     We  must  observée,  that     Cf'.sin.(2j; — 2vm)     is  the  inequality  depending  on 


[4931i]         The  next  term  of  [4931]  is     -^^  .  f  ^^-^.iôv'.cos.(2v—2v']  :      which    is    of    the 

Sv' 
order     — j-,     or     ot    [4922f/,  c],  in  comparison  with  the  terms  produced  by     a  du     in 

[4931^];  and,  as  tliis  last  function  may  be  considered  as  of  ihefoaith  order,  that  in  [4931t)] 
[4931m'J  may  be  supposed  of  the  fifth  or  a  higher  order,  in  all  the  angles  which  require  any  notice  ; 
so  that  it  will  only  be  necessary  to  retain  the  terms  depending  on  the  angles,  whose 
coefficients  increase  considerably  by  integration  ;  as  cv,  2gv — cv,  v — mv.  These  are 
produced  by  the  terms  of  aoii  [4904],  depending  on  ^4/'',  ^J''';  which  give,  by  the 
process  in  [4916,  4917],  the  following  terms  of  M  ;  namely, 

W^^A  Sv'  =  —  2;n.^/"e.sin.(2t)— 2my— ci')— 2m.^i'''.-,.sin.(î>— mi>). 

Now,  if  we  multiply  — ^.Sv'.dv  by  the  first  member  of  [49107c],  and  prefix  the  sign /,  it 
produces  the  term  [4931  !)].  Performing  the  same  operation  on  the  second  member  of 
[4910A:],  we  find,  that  it  becomes, 

2 

'^        ^'  — .y"^(5y'.  f/tiX  terms  between  the  braces  in  [4910^]  I . 

The  first  term  of  ôv    [4931:c],  being  combined  with  the  first  line  of  [4910A:],  neglecting  e^, 
[4931:1    produces  the  term  [4932a]  line  1  ;  the  same  term,  combined  with    1^^.  cos. (2^1- — 2i'-f-2mD) 
[49 10A-]  line  12,  gives  [4932a]  line  2.     The  second  term  of  [4931  x],  being  combined  with 
the  first  of  [4910A;],  produces  [4932«]  line  3  ;  hence  we  have, 

Third 

t^'otoc  -  f  — m.AJ".e.(\ — Pje''^).cos.cv    ~\  ^ 

the  fuiic-  2»  '\-/  i  A 

[4932a]  ./ .|5u'.cos.(2y— 2i)  )= .    <    -Ti.^-^^   .cy  .cos. (zgv—cv) 

''"'''  "'  "'  I  ™         /J>17)"  /  N         \ 

I ; .Ji  .^".-.cos.iv — mv)      \  3 

I  1 — m  a  ^  'I 


2 


These  terms  are  the  most  important  ones  of  those  depending  on    Sv',  and  they  are  only  of 
[4932i]    ti^e  fifth  or  sixth  order;  therefore, it  will  not  be  necessary  to  notice  the  terms  arising  from  the 
multiplication  of  these  by  the  factor     ^■y^.cos.'igv     [4931]. 

_,,  .  ^, /dd6u   ,    ,   \       -3  m'.  u'3.  (/w 

[49326']         The  next  terms  of  [4931]  are     —f— -+oi«j./ — —- — .sin.(2«— 2d')  ;    which 

will  evidently  be  obtained,  by  multiplying  the  function  [43S5],  by  the  factor     (  -,—-{-  <5m  j. 

[4932f]    Now,  any  term  oï  mhi  [4904,4912],  being  represented   by     aSu  =  k. cos. {((-{-s),     the 

[4932c']    corresponding  term  of  this  factor  will  be ■  {r — l).cos.(i<-|- f)  ;     ^ind   the   product  of 

the  terms  of  this  kind,  by  the  corresponding  ones  in  [4885],  are  computed  in  the  following 
table  ;  putting    c^l,    ^=^1,    in  some  of  the  small  terms;  but,  in  the  term  depending  on 


VII.  i.  §8.J  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  445 

siu.(2t' — 2mv),    in  the  expression  of  the  moon's  mean  longitude  in  terms  of      [4930] 


the  angle    2gv — cv   [  193-2/line  7],  we  must  use    f=l — |m-,     g^zlJ^îm^  [4932,4933], 
which  give,  very  nearly. 


(0_^,„,),-2  -(2+«)-)' 


l+jni\  (l—im). 


4.(2o-— 2-t-2/H)       4\-2m-{-^m-)  4m.  Vl+lmy  4m 

by  which  means  the  coefficient  of  the  tenn,  in  col.  2, line  7  [4932/],  becomes   —(l-im).~. 

•I  in 

Moreover,  the  fictor     — (1- — l)./i:     [4932c']  becomes,  in  this  case,  by  neglecting  dv', 

— {(2-2/«-c)--ir.2/"e=— Kl-2'«+l'«')'-U--4/'^c  =  (4m-7«/2).^/n,^4^(l_Z;„')^(,)g_ 

Multiplying  tills  by  the  factor    _^^*^     [4932e],  we  get     —{l—2m).A'-^\ef     for  the 

factor  of    cos.(2^y — cv),     in  line  7  [4932/]. 

(ci.  1.)  (Col.  a.)  (Ci.i.  3.) 

Terms  of  adit  [4904].  Terms  of  [4885].  Corresponding  terms  of  the  function  [49326']. 

.,-2 

•Sill 


[4939a'l 

[4932d'] 
[4933e] 

[4932e'] 


.Î2"".cos.(2i;— 2mr) 


^i"e.cos.  (2v — 2mv — cv' 

w3.J'e.cos.(2u— 2/nt)+ci;) 
^Ip'e'.cos  (2«-2m«+c'?rtî)  ; 
A'^^e  .co5[2v-'2mv-c'  mv) 
A[^^Y.cos{2gv-'2v+2mv) 
•-I,   '.-,.cos.(î) — mv) 


-^ ' — .cos.f2i'-2mj;) 

2— 2m  ^  ' 


-2(1 -f-w) 


-9(l-,«) 


2-2m+c 
7c' 


,e.cos(2u — 2mv—cv 


e.cos(2w— 2mi'-f-ci'' 


>.a.-.cos.(3y — 3mv) 


2(2-3m) 

e' 
~2(2-m) 

(i-yg; 

2-2m 


-  .c  os(2t! — ^mv-c'm  v  ] 


Thrse  terms  have  tlie  factor 


J4(l-m)3-]| 


2(1— jn) 


,^^»>.(1— |e'2) 


cos.(2u-2nM)-[-c'ni!j) 
.cos. (2d — 2mv) 


--- !— 1-  .cos(2g-i;-2u+2mv 

4(%--2-f2m) 

2— 2fft 
1 


2— 2ffi 
1 


cos.(2d — 2mv) 
cos.(2ti — 2mv) 

— 2e-cos.(2«—  2mv—cv) 
.cos.(2y — 2mv) 


2—2/, 


'2_o    cos  (2y — 2mv) 


+  |4(l-;»)2-l }  .gb^^^^fo,  e.eos.c.       2 

+  {4(l-m)2-l  }.^<i=^.^|.)e.cos.c«        3 
<c—^m-\-c 

.l4{l-my'-l}.^^^.AI'V.cos.c'mv    4 

+  {4(  1_m)2— I  |.-i— .^^o,e',cos.c'm«      5 
(  (2-2m-c)a-l  )     ^.  ,     , 

— (1— 2m).^i"c;.2_cos.(2^y_ct,) 
— 4(1— Ae'2).^.^(2^e.cos.cy     nearly 


..^,'3', 


e  .COS. cmv 


.cos.c  mv 


VOL.   III. 


112 


^  (2-m)g-l  ^ 
i  2(l-m)  ^ 
C  (2— 3m)2— 1  ) 
(      2(l-m)      ^   ^-^ 

—2A\'^'>ey^.cos.{2gv—cv) 
,     C  1  —  9.(1— m  )9)         a 

+  { -2=2;;r~  \  ■'^-^■^^A^^^^)-    13 


7 

8 

9 

10 

11 


Develop - 
inent  of 
the  fourth 
term  of 
tlio  func- 
tion [49J1  I 


[4932/J 


446  THEORY  OF  THE  MOON  ;  [Méc.  Ctl. 

[^•^3fi']     its  true  longitude   [5095]. 


The  last  term  of  the  function   [4931]  is, 


[4932gr] 


9m'       „H'2.(5tt'   -,      .     ,^ 


r4933A1  '^°  develop  it,  we  have,  by  retaining  only  the  first  power  of  e',  a'M'=l-)-e'.cos.c't;' 
[4833],  whose  variation  is  a'&u'= — c'e'.Sv'.s'm.c'v'^ — e'&v'. sin. c'mv,  nearly;  and,  by 
substituting  the  value  of  &v'  [4931  r],  we  find,  that  Su'  is  of  ihe  fourth  order;  consequently, 

[4939i']  the  expression  [493'2o-]  is  composed  of  terms  of  the  sixth  and  higher  orders  ;  and,  as  the 
integration,  in  [4932§-],  does  not  have  the  effect  to  increase  essentially  these  terms  of  the 
sixth  order,  the  whole  expression  may  be  neglected. 

AVe  have  thus  computed  all  the  terms  of  the  function  [4931].  Nothing  now  remains,  but 
to  connect  togetlier  the  terms  which  depend  on  the  same  angles,  as  they  are  found  in  the 
[4932A:]  functions  [493  1|j,  w,  49323,/"].  The  sum  of  these  four  functions  ought  to  be  equal  to  the 
development  of  the  expression  given  in  [4934],  neglecting,  for  a  moment,  the  consideration 
of  the  terms  depending  on  C  [4935,  &lc.],  which  will  be  noticed  in  [4937«,8>:c.].  In 
finding  the  sums  of  these  coefficients,  it  will  be  necessary  to  make  some  slight  alterations,  to 
reduce  them  to  the  forms  adopted  by  the  author  in  [4934].  This  will  be  done  in  the 
remainder  of  this  note. 


[4.9321] 


[4939m] 


[4933)t] 


First.     The  term  in  [4932/'line  I],  which  is  independent  of  any  angle,  corresponds  to 
[4934  line  I],  without  any  reduction. 

o  — " 

Second.     The  second  term  of  [4934]  has  the  factor —  c.(l — ^e'^)  .cos.  (cv — to) 

common  to  all  its  terms  ;  and  the  terms  by  which  this  factor  is  multiplied,  in  the  functions 
which  we  have  mentioned  in  [4932Ar],  are  collected  in  the  following  table,  in  the  order  in 
which  they  occur,  without  any  reduction,  except,  that  the  two  terms  [4931p  lines  2,3],  are 
reduced  to  one  in  line  38. 


[493 Ip]  lines  38, 6,  12,18,21 
[4932rt]  line  1 

[4932/]  lines  2, 3 
[4932/]  lines  6,  8 


+8;n..^o"'+2.^;"— 2^^->— ^i«.e'2+7./î<;'.e'2  1 

+2m.^;'i  2 

_H,(,-,.).-,s.^,-i£-^+,j=:^|,A».  3 


The  coefficient  of  A[^\  in  this  table,  is 

^  ,  ^      ,  (2-2m— c' 
4.(1— Î" 

and,  by  neglecting  the  term  m^,  in  the  numerator,  which  produces  only  terms  of  the  sixth 


(2-2m-c)2-l         7-8m5-H2-2m-c)a 
[4ft52o]  2+2m+— --^--  = ^^j-^^^j 


VII. i. ^^8.]    DEVELOP.AIENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  447 

C,<«'.e'.sin.(2  v — 2  m  v  j-c'm  v—^')     and     C^"''.c'.sin.(2  v — 2  m v—c'm v-{-a)        [4937] 


order  in  [4934],  which  are  usually  rejected,  it  becomes  equal  to  the  coefticient  of  A'-p,  in 
[4934  line  2].  We  may  also  omit  the  term  Qm.A':^  [4932?i  line  ]],  which  is  of  the  same 
order;  and  then,  the  remaining  terms,  connected  with  A^^\  in  line  3,  are  the  same  as  in 
[4934  line  2J.  The  terms  depending  on  .^/~'  [4932ij  lines  1,4],  mutually  destroy  each 
other.     The  remaining  terms,  depending  on    ./3/''',    A'-p,  are  as  in  [4934  line  3]. 

Third.  The  third  term  of  [4934]  has  the  factor  e'. cos. {c'liiv — w')  common  to  all  the 
terms.  The  coefficients  of  this  factor,  in  the  functions  mentioned  in  [4932Z:],  are  given  in 
[4932«],  in  the  order  in  which  they  occur  ;  observing  that  the  two  terms  in  [4931/3  lines  4,  5], 
as  well  as  those  in  lines  9, 10,  are  reduced  to  one  in  [4931^  line  39].  Moreover,  the  terms 
of  [4931yj],  depending  on  the  angle     c'mv — ro',     have  the  divisor   m,  wiiich  is  introduced 

by  the  integration  ;  and  they  have  also  the  common  factor  —  ;  so  that  they  are  all 
multiplied  by 


6  m 
a,.m 


fi.fma— em")        fim      3m3       ,^^^,^  6m 

= =  — 1 5094   ;     or     —     nearly 

3m3 


neglecting  the  term ,     which  produces  only  terms  of   the  sixth  order    in    [4934]. 

Hence  the  factor  of     c'.cos.(c'm2; — ra')     becomes,  without  any  other  reduction,  as  in    the 
following  table  ; 

Cm    ,     „, 


[4931/7]  hues  39,  13,14,  17,20 
[4932/]  lines  4,  5 
[4932/]  lines  9, 10 


.\AA'f—\OA'^\e~-\-A.}''^- 


3SÎ 
'4 


-.  j  A.(\-mf—\\jU->\  \  — î_  \ 


By  altering  a  little  tlie  arrangement  of  the  terms  in  the  first  line  of  this  table,  it  becomes  as 
in  [4931  line  4]  ;  the  second  and  third  lines  of  the  table,  correspond  respectively  to  [4934] 
lines  5,  6.     The  terms  relative  to  C,  in  [4934  line  7],  are  discussed  in  the  next  note. 

Fourth.  The  eighth  and  ninth  lines  of  [4934],  correspond  to  [493 Ip  lines  22,  23], 
respectively.  The  tenth  line  of  [4934],  depends  on  [4931/?  lines  7, 16].  The  eleventh 
Une  of  [4934].  depends  on  [4931/;  lines  8,19].  The  twelfth  and  thirteenth  lines  of  [4934], 
correspond,  respectively,  to  [493Ip  lines  24,  26]. 

_a 

Fifth.  The  factors  of  —  .672.003.(2^1)— cy),  in  the  functions  mentioned  in  [4932it], 
are  contained  in  the  following  table; 


[49.32/)] 


[4932^] 


[4932r] 


[4932»] 


[4932<] 


[4932u] 


448  THEORY  OF  THE  MOON  ;  [Méc.  Ce!. 

[4937']     *are  the  inequalities  depending  on  tlie   angles     2v — 2inv-'rc'mv — 35'     and 


[493^!''] 
[4932i>] 


[493 1  p]  lines  11,  27,  30 
[493  lit] 
[4932a]  line  2 
[4932/]  lines  7, 1 1 


+im.A['^  3 


Sum  =  +|m../?,''4-2^^'3'— ^["5>. 

This  sum  agrees  with  the  coefficient  in  [4934  line  14],  except  in  the  term  depending  on 
«^'j'',  which  is  Jm.^'/'  instead  of  ^m.Jl[^K  The  difference  is  of  the  seventh  order  only, 
and  is  hut  of  little  importance,  producing  only  terms  of  the  fifth  order,  after  integration,  in 
[4847].  This  discrepancy  appears  to  have  arisen  from  putting  ^=1,  c=l,  in  the 
[493ar'l    calculation   [4932e,  e'],  instead  of  the  values   [4932,4933].     For,  by  using    ^  =  1,     the 

/  I-l-A  m) 

factor  r4932rf',e]  becomes        .   -,    and  the  fiictor  r4932e'l  is 

4ni  -' 

—  \{2—2m—cf—l\  =  _{(l_2m)2— 1*  =4in—4m^=4m.{l—m). 

The  product  of  these  two  factors  is  nearly  equal  to  — (1 — i»i),  instead  of  • — (1 — 2//i) 
[4932w]  [49;3-2y  Ijne  7].  Hence,  the  coefficient  of  m  is  decreased  to  one  quarter  part  of  its 
former  value,  and  the  term  |m..^j''  [4932y],  will  be  decreased  in  the  same  ratio,  so  as  to 
become  Jjn-.^'j''  ;  by  which  means,  the  sum  of  all  these  terms  ^m.A\'^  [4932i)],  is 
reduced  to     |m.^,'\     as  in  [4934  line  14]. 

Sixth.     The    term   in    [4934  line  1.5],  corresponds  to  that  in  [4931p  line  29].       The 

factors  of     — .  — .cos.(y  —  mv),     in   the    functions   mentioned  in    r4932/i:],   are 

2«,.(l— m)   a  ^  ' 

contained  in  the  following  table.     The  sum  of  these  factors  corresponds  to  that  in  [4934] 

line  16,  neglecting  terms  of  the  order     m^.A["\ 

+     4.4f/'>-2.4<'«.e'^— 4>2 
+4m...^i>^i 
-I  { l—{l-mf\..f,^'>  —X,.  \  i—l{l-my^ 


[49.32.T] 


[4931p]  lines  31,  35,  37 

[4932«] 

[4932/]  lines  12,13 


Sum  =  {4+3m).J[''^—2J]',"'\e'^—i\_.  \  1— (l-m)*2| . 


Seventh.     The  terms  in  [4934  line  17],  correspond  to  those  in  [4931/?  lines  33,  36]  ;  and 
[4933i/]     the  terms  of  [4934  line  18J,  correspond  to  [4931^  lines  32,  34].      Hence   it  appears,  that 
all  the  terms  we  have  computed,  agree  with  those  in  [4934]. 

*  (2829)     If  we  compare  the  value  of     nt-^s     [4828]  heretofore  used,  with  the  form 

[4937al     finally  adopted  in  [5095],  we  shall  find,  that  the  terms  depending  on    ft",    O,'',  hc.C^P, 

p.qg-,,     have  been  neglected  ;  and,  if  we  put    C   for  the  sum  of  these  terms,  we  must  add    C   to  the 

value  of    nl-\-e  [4828],  which  will  introduce  in  the  second  member  of  [4836]    the  term 


VIL  i.  ^^  3.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u. 


449 


2v 2mv — c'mv-'r^',     ia  the  same  expression.     We  may  also  observe,  that     [4937"] 

the  term, 


Cm  ;  and  the  same  quantity  in  the  second  member  of  [4837]  ;  and  we  shall  represent  this 
increment  of  v',  by  the  expression  5v'=^  Cm.  Substituting  this  in  a'Su'  [4932^],  we 
get  a'ôu'^ — Cme'.sm.c'mv.  Now,  if  we  select  the  chief  terms  of  [4910,  4931],  depending 
on    Sc',    Su',  they  will  become 

J«'.sm.(2!)  —  2y)+— r-  .  /  • — —.tM.cos.{9,v — 2«')  — —  ./  — — .rfv.sin.(2u-2w'). 


fc3.  u3 


[4937c] 
[4937rf] 


[4937e] 


We  have  neglected  the  last  term  of  [4924],  depending  on     &v',  because  it  is  multiplied  by 

— ,  which  is  of  the  order  e  [48T8]  ;  so  that  this  will  be  of  the  same  order  as  the  product 
dv 

of  the  first  term  of  [4937e]  by  e,  which,  as  we  shall  soon  see,  may  be  neglected  [4937À:]. 
Now,  substituting  the  values  of  &v',  Su'  [4937c,  rf],  in  [4937e],  it  becomes,  by  merely 
altering  the  arrangement  of  each  of  the  terms,  so  as  to  bring  them  under  the  forms  we  have 
already  computed, 

{  'âS-^^-^^^-^'^  ]  •2C^+4^:./'^".cos.(2.-2.').f  C. 

,      9?»'         «M-  .  ^    /\   "'C     ^     .         , 

+  --— .  /  —.dv.sm.(2v — 2v).—r.C.sm.cmv. 

The  value  of  C,  to  be  substituted  in  this  expression,  is  easily  deduced  from  [5095,4937tl, 
and  is  represented  by 

C=Cf.sm.(2v—2mv)-{-C[''\e.sm.{2v—2mv—cv)-\-Cf\e.sin.(2v—'2mv-\-cv) 

-\-C'^\e'.5m.(2v~2mv-j-c'mv)-\-C^"'\e'.s'm.{2v—2mv—c'mv) 

-\-Ci"Ke'.sm.c'mv-{-hc.  .  .  .-{-C['^\~.cos.{v—mv)+hc. 

If  we  multiply  together  the  two  functions  [4876e,  4937A],  and  the  product  by  2m,  we 
shall  get  the  first  term  of  tiie  function  [4937^J.  These  terms  of  this  product  are  of  the 
Jlfth  and  higher  orders  ;  so  that  it  will  only  be  necessary  to  retain  those  which  depend  on  the 
angles     cv,     v — mv.     These   tenns  are  found  by  multiplying   the   first  term  of  [4876e], 

2 

O — 

namely,     '^.sm.{2v—2mv),     by  the  terms  of    2mC    [4937/;]  depending  on   C,"',    C['^^; 
4a, 

from  which  we  get, 

in  which  we  have  neglected  some  terms  of  the  sixth  order,  depending  on  C^'^',  and  on  the 
angle   cv. 


[4937/] 


[4937g] 


[4937/i] 


[4937»] 


[4937*] 


VOL.   III. 


113 


450 

[4938] 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


6m 


.{^A'^'>-\-Af--Afl.e'.cos.(c'mv—^'), 


[4937«] 


The  next  term  of  [49375-]  is  found  by  multiplying  together  the  functions  [4910Â:,4937/i], 
and  the  product  by     — ^m.dv  ;    and  then  integrating  the  result  ;  as  in  the  following  table  ; 


Terms  of  [4937/t]. 
-\-Cf\sm.{2v—2mv) 


[4937m] 


+  C-p  .e.s\n.{2v — 2m« — cv) 
+  Cf''e'.s'm.{2v—2mv+c'mv) 
-f-  C™^e'.sin(2u — 2mv—c'mv) 
-\-a^'>\-,.sm.{v—niv) 


Terms  of  [4910Â:]. 

4-cos.(2« — 2niv) 

— 2e  .cos .  {2v — 2mv —  cv  ) 

— 2e.cos.(2w — 2mv-{-cv) 

+  Je'.cos.(2î) — 2mv — c'i7iv) 

—  I  e'.cos.(2i) — 2mv-\-cmv) 

-j-cos.(2y — 2mv) 

-|-cos.(2t; — 2mv) 

+cos.(2i) — 2mv) 

+cos.(2« — 2mv) 


Terms  of  [4934].        _3 

These  terms  have  the  factor    —  • 
a, 

.  .  .  .neglected  1 

-\-2Cf\7nc.cos.cv  2 

— 2Cj'-''.OTe.cos.ct)  3 

— i  Cf^.e'. COS. dmv  4 

— 2  C  f'.e'. COS. c'mv  5 

4-  O^^  .me.cos.cv  6 

—  CfKe'.cos.c'mv  7 

-(-C^^°'.e'.cos.c'?n«  g 

-\-C[^^\m.-,.cos.{v — mv).  9 


The  last  term  of  [4937^]  being  very  small,  we  may  substitute  in  it  the  values 


[4937n] 


14  =  -  ;        u'=z  -,  ; 


■  mv\ 


h^=a,     [4921«— c]; 


by  which  means  it  becomes, 


[4937o] 


[4937p] 


[4937g] 


'"""  .me',  f  dv.s\n.(2v — 2mv').sm.c'mvy,  C ; 

and,  by  using  [4S65],  it  may  be  reduced  to  the  form, 

— .  me'.  fCclv. {cos.{2v — 2mv — c'toî)) — cos.(2t) — 2mv-\-c'mv)  \ . 

Now,  substituting  the  value  of  C  [4937A],  it  produces  terms  of  the  sixth  order,  before 
integration  ;  and  some  of  them  may  be  reduced  to  the  fifth,  after  integration,  if  they  be 
connected  with  the  angle  c'mv;  we  shall,  therefore,  retain  this  angle  only.  These  terms 
are  found,  by  substituting,  in  [4937o],  the  part  of  C  [4937A]  represented  by 
C^''\sin.(2î) — 2mv).    Combining  this  with  each  of  the  terms  of  [4937o],  it  produces  a  term, 

rhdv.sm.c'mv  = .cos.c'mv  ;     so  that  both  terms,  taken  together,  produce  the  following 

expression  ; 

— .  f-l dv.s\n.(2v-2v').^ . C. sm.c'm v  =  — A— ^Cf\e'. cos  c'mv]. 


VII.  i.  §8.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  451 


[4938'] 


appears  to  be  of  the  order  ?«',  which  would  produce  a  quantity  of  the 
order  w^^  in  the  expression  of  the  moon's  mean  longitude  ;  but  this  term 
is,  in  fact,  only  of  the  order  m^.  For,  we  shall  see,  by  means  of  the  values 
of  4°',  Jf,  4^'*  [5157,5160,5161],  that  the  function  4Jf +4'— 4<''  [^«39] 
is  of  the  order  m^  ;  which  produces,  in  the  expression  of  the  mean  [4939'] 
longitude,  a  term  of  the  order  m'^  only.  We  shall,  however,  retain  it 
here,  because  we  have  imposed  on  ourselves  the  condition  of  including  terms 
of  that  order,  in  the  calculation  of  the  terms  of  the  third  order. 

For  this  reason,  it  is  indispensable,  in  the  development  of 

j^— .J  —^  .sm.(2v — 2v')     [4930],  [4940] 

to    carry  on    the  approximation  to  terms    of   the   order     6ii^  ;     hence   we 
obtain  the  terni,t 


Connecting  together  the  quantities  contained  in  [49.37A:,??î,y] ,  we  get  the  terms  of  the  function 

a 

[4937 e]  depending  on   C.     The  coefficients  of    — .Cf\é.cos.c'mv,    in  [4937m  lines  4,5], 

and  in  [4937(7],  being  connected  together,  become, 

—  J— I— 1  =  — ^S     as  in  [4934  line  7]  ;  [4937r] 
and  the  terms  in  the  same  line,  corresponding  to   Ci''^   C^"',  agree  with  those  in  [4937?»] 

lines  7, 8.  The  term  depending  on  Cf'  [4937ot  lines  2, 3] ,  mutually  destroy  eacli  other. 
The  quantities  we  have  mentioned  include  all  the  terms  retained  by  the  author  ;  who  has 
not  noticed  those  in  [4937^],  and  in  lines  6,  9  of  [4937?«],  whose  sum  is 

—  .m.  }  C[''\c.cos.cv-\-0^^'>,-.cos.{y^mv)  >  .  [4937s] 

These  neglected  terms  are   of  the  fifth  or  sixth  order,  increasing  also  by  the  integration  in 
[4847]  ;  and  are  of  the  same  orders  as  the  terms  which  are  usually  retained   with    these      [4937t] 
angles  ;  but,  as  we  did  not  wish  to  alter  the  numerical  calculations  of  the  author,  we  have 
not  introduced  them  into  [4934]. 

*  (2830)     These  values  are  nearly  represented  by      ^/''i=  0,0071,     .;32")__o^o030, 
^»iz=: 0,0285;     whence,     AAf-\-Jl'-^^—A'-^=—Qfi^Z,    nearly.     This  is  less  than     m~    [4938a] 
[5117],    but  can  hardly  be  called  of  the  order  m?,  as   in  [4939']  ;    however,  as  it  is 
multiplied  by  e',  which  is  much  smaller  than    e,   7,  in,   we  may  consider  the  whole  term    [49385] 
[4938]  as  of  the  order  m^. 

t  (2831)     The  factor    eu-    is  of  the  fourth  order  [4904],  and,  as  all  the  terms  we  have 


452 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4941] 


30m'. u     „u'3.fe2    ,      .      ,^        „   ,. 


This  term  produces  the  following  ;* 


computed  [4910,  4924,  &IC.]  have  the  factor  ?n',  or  m,  except  where  the  sign  of  integration 
[49327-)-]  has  introduced  the  divisor  m;  it  follows,  that  these  terms  depending  on  Su^,  are  generally 
of  the  sixth  order  ;  but  some  of  tliem  may  he  reduced  to  the  Jifth  order,  by  the  integration 
we  have  just  mentioned.  Tlierefore,  we  need  only  notice  those  terms  wliere  the  variations 
are  connected  with  the  signs  of  integration  ;  so  that  we  may  neglect  the  second  powers  or 
products  oftlie  variations  in  the  terms  [4909",  4921, 4924,4927 ,4931, &c.],  and,  in  fact,  only 
retain  the  chief  term  of  [4930  or  4931],  which  depends  on  Su^.  For,  we  need  not  notice 
the  terms  depending  5u.Sv',  Su.oii.  Sv'^,  Su'^,  &;c.  ;  because  &u  is  of  the  second 
order  [4904],  5v'  is  of  tlie  third  order  [4929^],  Su'  is  oï  the  fourth  order  [4929i — it]  ; 
hence,  the  terms  depending  on  hi.dv,  Su.Su',  &ic.  must  generally  be  much  less  than  those 
depending  on  Su^  ;  therefore,  we  shall  only  notice  this  last  quantity.  We  have  already 
[4941e]  found,  by  Taylor's  theorem  [610. &c.],  in  [49296],  the  increment  of  the  function  —  V.ffVdv  , 
arising  fi'om  the  increments  Su,  Sv',  Su',  in  the  values  of  m,  v,  u',  respectively  ;  and, 
by  the  same  theorem,  the  term  depending  on    om^,    will  evidently  be  represented  by 

—J  V.f  (^-^'\ .  Su\dv    [610,  49296] . 

Substituting  the  value  of  W  [4929«],  it  becomes, 


[4941a] 

[4941i] 


[4941c] 
[4941rf] 


[4941/] 


[4942a] 

[49426] 
[4942c] 


-30m'.  F     ^u'^.ixfi    ,     .     .^ 


7l2 


mO 


and,  by  using  the  value  of  F  =  -  =  w,     nearly  [4929Zr,4937w],  it  becomes  as  in  [4941]  ; 
neglecting  in   V  terms  of  the  order    em^,   e^,    y^. 

*  (2832)  As  the  function  [4941]  is  of  the  sixth  order,  before  integration  [49416]  ;  we 
may,  by  neglecting  terms  of  the  seventh  order,  substitute  in  it  the  values  [4937n]  ;  by  this 
means,  it  becomes. 


30)n'.a3  .   .„    . 
■;^.J  dv.^aSuy. %in.{2v — 'Hmv)  ■■ 


30? 


.fdv.{aSuf.sm.{'iv—'imv)      [4865]. 


If  we  retain  only  the  term  of  {aSuf,    of  the  fourth  order,  we  may  neglect  all  the  expression 
[4904],  except  the  two  fiist  lines,  and  we  shall  have, 

aSu=Jlf\cos.{2v—2mv)-\-Ap.e.co5.{2v—2mv—cv). 
Squaring  this,  and  reducing,  by  means  of  [20]  Int.  we  get, 

(«'5M)-=(^f)'-B+è-cos.(4îJ— 4fflD)|-f^^o).^<').c.{cos.c«+cos.(4r— 4mi'— a.)| 

+  (^i'O^-e^-  B+è-cos.(4i;— 4m!;— 2a.)  \ . 
This  must  be  multiphed  by     sin.(2u— 2mu),    and  the  product  substituted  in  [4942»],  after 


VII.  i.  §S.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  463 

2 

15  m      {A^py^.e^.cQS.{2cv—2v-\-2mv—2^)  _  ,^^^2] 

"207   *  2c— 2+2m  ' 

although  it  is  only  of  the  fifth  order,  yet,  as  it  acquires  by  integration,  in  the 
expression  of  the  mean  longitude,  the  divisor*     2v — 2+2m,     it  is  necessary      [4942] 
to  notice  it. 

The  function 

gives  the  following  ;t 

~  Vd^  +N'  F  '-^  — Âû^ {3.sin.(«— u')+15.sin.(3w— 3<;')^  [4944] 

Its  variation  produces  the  terms,! 

making  the  reductions  by  [18]  Int.  Tiie  only  term  of  this  product,  in  which  the  coefEcient 
of    V    is  small,  is  that  produced  by  multiplying  the  last  term  of  [4942c], 

i(^','')2.e2.cos.(4i' — 4m!; — 2c«),     by     sin.(2!; — 2mv)     [4942a],  [4042rf] 

which  produces  the  term  ^(.^','')^.e^.  sin.(2cy — 2v-\-2mv);  and,  by  substituting  this  in 
[4942a],  it  becomes  equal  to  the  following  expression  ; 

__.(A"')-V  ./-sm.(2a.-2«+2..)  =  _   .  2c-2+2>»  '  '       ^'''^^^ 

as  in  [4942].  The  terms  we  have  neglected  are  of  the  sixth  or  higher  orders  ;  the  term 
[4942]  is  reduced  to  the  fifth  order,  by  means  of  the  small  divisor  2c — 2-\-2m,  which  is 
neai-ly  equal  to    2m  [4828e]. 


*  (2833)  The  term  of  u,  resulting  from  the  substitution  of  [4942]  in  [4961],  is  to  be 
added  to  u  [4812  or  4819]  ;  and  this  produces  in  dt  [4753]  a  term  depending  on  the 
same  angle.  The  integration  gives,  in  t,  and  in  nt-\-s  [4828],  a  term  of  the  same  form 
with  the  new  divisor     2c — 2-\-2m  ;     and,  by  this  means,  it  is  reduced  to  the  fourth  order. 


[4943a] 


t  (2834)     The  terms  [4809],  depending  on  the  angles     v — v',     3v — ^v,     are  retained 
in  [4944]  ;  because  they  produce,  in   [4946],  some  terms  depending  on  the  angle     v — mv,     [49440] 
which  require  a  greater  degree  of  accuracy  than  the  others  [4906, &ic.]. 

X  (2835)     Since     5m',     5«',     are   much  smaller  than     Hu     [494 If/],  we  may  neglect 
them  in  finding  the  variation  of  the  function  [4944],  and  consider    u   as  the  only  variable    ^  ' 

quantity;  by  this  means,  the  variation  of  [4944]  becomes, 

VOL.  III.  114 


454  THEORY  OF  THE  MOON  ;  [Méc.  Cél 

I    /ddSu    ,       \       J,    vi'.u'*.dv 


•(-^^+ôttj  .J —^ — .|3.sin.(îJ— î))+15.sm.(ou— ot)}j 

[4945]  '  ^ 

+  —   .-  .  fa6u.dv.\3.sin.(v — i)')+15.sm.(3« — 3v')\; 

4  a,      a' 
hence  results  the  terra,* 


[4945a] 


/ddâu.    ,    .   \       1       ^    m'.u'^.dv      ,„    .      ,  ,s    ,  ,  _    .     /„        <^  ,>  i 

-  {1;^  +^V  •  P  •/— 4-,.T—  •l3.sm.(.-.')+15.sm.(3t-3.')| 

Substituting,    in  the  first   line    of  this    expression,    the  vakie      h^=a^      [4937n],    it 
becomes  like  the    first  line    of  [4945].      Again,    by  substituting,  in    the  second  line  of 

[49456]     [4945a],  the  values  of  M,    u',    P  [4937?f],  and  for     '~+u,     the  chief  term    -    [4890], 

it  becomes 

r4945cl  ■ — '—;:;  ■  —  •  fa5u,dvA3.sm.(v — y')4-15.sin.(3!; — '3v')  \  . 

'■  4a,.  a-'     a  i  ^  '  '  1 

This  is  easily  reduced  to  the  form  in  the   second  line  of  [4945],  by  the   substitution  of 
m'  [4865]. 

*  (2836)  The  terms  [4945],  being  of  the  sixth  order,  independent  of  the  integrations, 
it  is  only  necessary  to  notice  the  terms  depending  on  the  angle  v — mv;  and,  we  may, 
therefore,  substitute  the  values  [4937h],  in  [4945],  and  they  will  become,  by  using  [4865], 

.(  -^7-j-  ^"  )  •  7  •">  •/{ 3.sin.(y — ?OT)+15.sin.(3i> — 3mv)  j ,dv 

[4946a]  '  a 

-\ .  —  .faSu.  { 3.sin.  (u — m!;)-j-15.sin.  (3!) — 3m!;)  I  .dv. 

In  this  we  may  substitute,  for   «  Su,   its  two  chief  terms  [49426]  ;  and  a  little  consideration 
will  show,  that  we  may  even  neglect  the  part  depending  on    ./2/'^    because  it  does  not 
[49466]     produce,  in  [4946],  any  term  connected  with  the  angle     v — mv  ;     so  that  we  shall  finally 
have     aôu  ^Af\cos.{'2v — 2>nv).     Substituting  this  in  [4946a],  it  becomes, 

—  — -.jjw. \  1—^.(1— mf\xos.{2v—2mv).f{3.sm.(v—mv)-{-]5.sm.{3v—Smv)\.dv 
4o,  a 
[4946c]  J 

^  —  ,-.^'M.fcos.{2v—2mv).l3.sm.{v—mv)-{-l5.sm.{3v—3mv)l.dv. 
Now  we  have. 


VII.  i.  §S.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  455 


"'        ,{\S-\-^.(\—m)-\.Af\-,.co^.{v—mv).  [4946] 


2a,.(l— ?«)    '  ^  '  ^      ^     a! 

We  must  here  make  an  important  observation  relative  to  the  terms 
depending  on  cos.(^' — m  v),  which  we  propose  to  determine  with  accuracy. 
The  expressions  of  the  radius  of  the  sun's  orbit,  and  its  longitude,  contain 
terms  depending  on  the  angle  v — mv  [4324],  resulting  from  the  moon's  [4947] 
action  upon  the  earth.  These  terms  produce  others,  in  the  expression  of  u,  J"^,'^'^^^^ 
and  in  the  moon's  mean  longitude  ;  and  it  is  essential  that  we  should  notice 
these  terms.  For  this  purpose,  we  shall  observe,  that,  in  consequence  of  the 
moon's  action,  the  sun's  radius  vector  contains  the  term 

6r'=  -.cos.(t;— «')     [4315,  43166]  ;*  [4948] 


3  5 

riS.sm.(v—mv)  4-l5.s'm.( ov—3mv)\.dv  =  — .cos.(v—nw)—- A:os.{3v—37nv).    [4946d] 

Multiplying  this  by     cos.  (2u  —  2}nv),      and   retaining    only  the    terms  depending  on 
cos.(y — mv),     we  find,  that  the  product  becomes, 

( ; ).icos.(î) — mv)  =— -.cos.(îJ — mv)  ; 

\       1—m       1 — m  J  "  1 — ni 

hence  the  first  line  of  [4946c]  becomes, 
m 


'- — ^, .  i  —24-8.(1— m)^  !  .Jli'>\-.cos.(v—mv).  [4946e] 


Again 


2o,.(l-m) 

cos.(2f — 2mw).3.sin.(î; — mu)  =— â.sin.(i) — mv)-\-iic. 
cos.(2u — 2mw).15.sin.(3î) — 3mv)  =-y*-.sin.(«) — mv)-\-&iJC. 

whose  sum  is    6.sin.(j; — mv)  -\-  &ic.      Substituting  this  under  the  integral  sign  of  the  second 
line  of  [4946c],  that  line  becomes, 

—  -  _2 

5«i     a    .,p,  6.cos.(î>— ;ni»)  m         ,  c  ^  ,01  «  /  x 

—  7—  .  -../2o™' = =  —  --— .làAé'^'.  -  .cos.fi) — mv). 

4  fl,     a      ~  \—in  2a. (1—m)  ~      a 

Adding  this  to  the  part  [4946e],  it  becomes  as  in  [4946]. 

*  (283T)     The  inequality  of  the  earth's  radius  vector,  arising  from  the  action  of  the 
moon,  is 


[4946/] 


m 


^''--M^^'-^'-^'^'-i^-''")     [4315,4316J].  [4948„3 

To  conform  to  the  present  notation,  we  must  change    U  into  v  [4313,4760'],     R  into  r, 


466  THEORY  OF  THE  MOON  ;  [Méc.  Cél, 

r4948'i     '^     being  the  ratio  of  the  moon'' s  mass  to  the  sum  of  the  masses  of  the  moon 
and  earth.     This  gives,  in    u',    the  term,* 

14949]  &U'=—'^.C0S.(V-V'). 

u 

The  longitude  of  the  sun  v'  contains  also  the  term  [4814],t 

[4950]  i.v'=-^.ûn.(v—v'). 

u 

This  being  premised,  the  term         '    3     [4865']  contains  the  following  :t 

[4951]  ____.cos.(^^— Î)). 

3m'  u'^ 
[4951']      The  term      --^  .cos.(2t?— 2i'')     [4866'],  contains  the  two  following  § 


—  pn*5 


[4952]  _  ^^^  .cos.(?;— z)').cos.(2i;— 2v')  +^^~.sin.(«— '«').sin.(2ij— 2^;')  ; 


[49486]      [4313,4759],   r"  into    ?•'  [4313,4759'];    moreover,   the  longitude   v"  of  the  earth,  seen 
[4948c]      from  the  sun    [4313],    is   equal  to    180''  +  '^'  of  the   present  notation    [4777rf]  ;    lastly 

[494erf]     ^=_^     [4757,4757', 4948'].     Substituting  in  [4948a] ,  we  get     5r'^,j.r.cos.{v—v'}; 

and  if  we  neglect  the  square  of  the  inclination  of  tlie  moon's  orbit  to  the  ecliptic,  we  may 

[4948e]     put    r  =  -     [4776],  and  then  the  preceding  value  of  S/    becomes  as  in  [4948]. 

*  (2838)       From    r4777el    we    have,    very    nearly,      r'=:  - ,;    whence     5r'= -. 

[4949a]  ^  ^  ^  ■•  '         }  :  „"  „'2 

Substituting  the  value  of   &r'  [4948],  we  get  Sti   [4949]. 

t  (2839)     This  term  is  given  in  [4314,43l6i],  under  the  form 

M-\-m      r'  ^  ' 

and,  by  making  the  changes  in  the  symbols,  as  in  [4948J,&,c.],  it  becomes, 

[4950a]  (5v'=-(-fji.— .sin.(t) — ■«'),      or  nearly      'V=fx.  — .sin.(j; — i)'),     as  in  [4950]. 


X  (2340)     The  variation  of  the  term         "  [4865'],   taken    relatively    to     ?t',     is 

[4951a]  ^    ,^  ^^'■'^ 

"      .i5m'  ;     and,  by  substituting    hC   [4949],  it  becomes  as  in  [4951]. 

§  (2841)     Taking  the  variation  of  the  term  [4951'],  relatively  to   «',   v\     and  then 
*■  substituting  the  values  of  5m',   h'  [4949, 4950],  we  get  [4952]. 


Vll.i.^8.]    DEVELOPxMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  u.  467 

which  produces  the  term,* 

'3m^.^  [4953] 

Connecting  it  with  that  in  [4951],  we  obtain, 

9?«'.  fA.?«'*  ,.  [4954] 

whence  results  the  following  terms  ;t 

2  2 

9râ.(x  ,  .        9m. fA     a  ,.  , 

^Scos.fi' — mv) .  -.e.cos.(« — mv+cmv — w  )  1 

4a,  «^       ^  ^         4rt        ff'  ^  ^ 

.-.e.  cos.(« — mv — cmvA-vi).  z 

4a,       a'  ^  ^ 


[4955] 


3  m'         m'^  dv 
The  term —  .y  ^— .sin.(2« — 2w')     [4882]   gives,    in   like   manner,     [4956] 

the  following  ;t 


*  (2842)     If  we  retain  only  the  angle  cos.(« — v'),  and  reduce  the  products  by  [17,20] 
Int.,  we  may  substitute,  in  [4952],  the  values 

cos.(« — i;').cos.(2u— 2w')^J.cos.(y — t)')-j-fcc.  ;  '  [49531 

sin.(«; — i;').sin.  (2u — 2y')  =  |.cos.(r — v') — &,c.  ; 
and,  since     — f-s+f-i  =  — tj     the  expression  [4952]  becomes  as  in  [4953]. 

t  (2843)     Multiplying  [4872]  by     — 2,a,     and  neglecting     e^     c'2,     we  get  [4955].       [4955a] 

f  (2844)     The  variation  of  the  term  [4956],  is  as  in  [49566];  substituting    the  values 
of    6u',     ôv'     [4949, 4950],  it  becomes  as  in  [4956c]  ;   reducing  the  products  of  the  sines    [4956o] 
and  cosines,  by  [18, 19]  Int.,  retaining  only  the  angle     v — v',     it  becomes  as  in  [4956(Z]. 

— ./  { .sm.(2i' — 2«  )H ; —  oi;.cos.(2u — 2y  )  }  [4jao6j 

=  -j^'f]  — ^— .sm.(2«— 2i)).cos.(j;— d')H ^  .cos.(2t)— 2z)').sin.(ii  — i)')  [  [4956e] 

3m'. {J-    ^(  3u"'.dv    .     ,  .        !<'lrfu  >         3m'.  ^     ^m'^.  rfy     .  ,.  r4.q';fi//1 

This  last  expression  is  evidently  equal  to  the  first  member  of  [4889]  multiplied  by     — 2/x  ; 

and,  if   we  multiply  Its  second  member  by  the   same  factor     — 2fJ.,     we   shall   get  the     '■         ■■ 

development  [4957]  ;  neglecting  the  small  terms     e^,     7^,     e''^. 

VOL.   III.  115 


458  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


3 


^        -  .  -, .  COS.  (v—mv) -r-  .  -  .  -.e'.cos.{v—mv+c'mv—^)  1 


[4957] 


2.{l—m)      a,      a' 


2 

9m.iJ'         a      a     ,  ,        ,     i\    c, 

2.(1— 2m)    a,     a'  ^  ^ 


There   remains  yet  to  be  considered  the    part  of   the    development  of 

[4958] .     [4893],   depending  on  the  square  of  the  disturbing  force. 

W.{\-\-ss)'^ 

g 

[4959]      rpj^jg  development  contains  the  function*     —  .  {hsf,      which    produces    the 
following  terms  ;t 


*  (2845)     We  have,  by  Taylor's  theorem 
[495G/]  -pC^^^*)  =  ^'^''  •  -Ï  +*("->  •    rf.2 


,4.5,)=,,+,3..^'+H«'^-)^-'^  +  &^c.       [617] 


where  the  terms  of  the  second  order  are  represented  by     i(fîs)^.  — r-^.     Now,  putting  the 
function  [4958]  equal  to     9(4),     and  developing  it,  we  get, 
[4956^]  <p(,)__A-2.(i+,,)-i-=_/r2.(l_3s2+^V-&c.).  . 

Its  second  differential  gives, 

[4956/.]  ^=-'^''"-1?''~'*'+^<^-=^^  =  ^     "^^^'y     [4937»]; 

neglecting    s-,    &ic.       Substituting  this  in   the   terms    depending  on     {hs)^     [4956/],   it 

3 
becomes     — •('5*)"j     as  in  [4959].     The   terms   of  the  order     ^^.{i)s)^,     which  we   have 

[4956i]  here  neglected,  are  of  the  order  7^  [4811],  in  comparison  with  those  which  are  retained 
and  developed  in  [4960]  ;  they  must,  therefore,  be  of  the  sixth  or  seventh  order,  and  are 
not  usually  noticed. 

t  (2846)     If  we  separate  the  terms  of  h   [4897]  into  classes,  of  the  second,  third  and 
fourth  orders,  by  putting 

[4960a]     6;=Bi°>.7.sin.  (Sv— 2m«— ^«)  ; 

S3=jB^'>.y.sin.(2î) — 'imû-\-gv)-\-B'^^.t'j.ûn.{gv-\-c!mv)-\-'Bf^.e'j.ûx\.{gv — c'mv) 

-\-lif' .  t' y  .s\'a..{^v — 2mii — gv-\-cm.v) 
[49606]  ■\-Bf^.e'y.^m.{2v—S>mv—gv—c'mv)  -^Bf\(?y.sm.. (2ct-^d)  ; 

S:^=B^\ty.%\x\.{2v—'i,mv-\-g'o — czi)-[-the  remaining  terms  of   &   [4897]  ; 

the  index  of    S   denoting  the  order  of  the  terms  ;   we  shall  have     &=-S'3-[-<Si3-[-'S4  •      Its 
[4960c]      square    is      (&)2=.S'2. ^o-|-2S2.(Sa-j-2So.  5'4+»S3 .  1S3;     neglecting   terms  of  the    seventh 


Vll.i.  §9.]  DIFFERENTIAL  EQUATION  IN  M.  459 

£-.(5{»)/.j«  1 

-\-~.\Bf^^B["'^\.BfKeY.cos.{c'mv—^)  2     [4960] 

/ill 

+  ~ .  Bl'K  5f .  e7^.cos.(2gv—cv—2è+z^).  3 

9.  We  shall  now  collect  together  and  reduce  the  different  terms  which 
we  have  calculated  ;  and,  bj  these  means,  we  shall  obtain  the  following 
development  of  the  equation  [4754]  ;* 


order.  Substituting  the  values  of  .S, ,  S3 ,  S^ ,  and  tlien  reducing,  by  means  of 
[17 — 20]  Int.,  retaining  only  the  usual  angles  and  terms,  we  get,  by  observing,  that  the 
terms  depending  on  Bî,^'  maybe  neglected,  on  account  of  its  smallness  [5177], 

S,.S,^UBrfr-; 
2S.2.S3  =  \B^;\B'f+Bf\B[">^\.eY.cos.(fmv; 
2So.Si  =  B^^KBi'\cf.cos.{2gv-cv)  ; 

S3. 83^  terms  which  may  be  neglected. 

The  sum  of  these  terms  gives  the  value  of    (&)^     [4960c],  which  being  multiphed  by 

3  3 

2^     gi^es     2^-{^^f'     as  in  [4960]. 


[4960rf] 


tioti   lU 

u. 


*  (2847)     We  have  thus  finished  this  elaborate  development  of  the  terms  composing  the 
equation   [4754]  ;  and  we  must  now  connect  together  the  different  terms  ;   namely,  those 
which  are  contained  in  the  twenty  Junctions  [4866,4870,4872,4879,4892,4595,4901,     [4960«] 
4908,4911, 4913,4918,  4922, 4925,4928,4934, 4942, 4946,4955,  4957,4960],  and  add 

'  -"  Function» 

ddll  wliich 

to  the  sum  the  tu'ojirst  terms  of  [4154];  namely,     — -|-m,     as  in  the   two  first    terms  of    J"!?'""' 

tial  equa- 

[4961].     In  performing  this   part  of  the  operation,  we  shall  take  the  terms  depending  on 
each  angle  separately,  in  the  order  in  which  they  occur  in  [4961]. 

First.     The  constant  terms  of  [4961  line  1],  are  found  in  [4895,  4866  line  1],  without 

9 
any  reduction.     The  tenns  having  the  common  factor  — - —  ..^^''^(1 — |e'2)      are   found  by 

adding  together  the  terms  in  the  first  lines  of  [4911,4925,4934]  ;  namely,     3,     — 2-j-2m, 

4.1 1— m)- — 1  .  1 

~^~Y^ •     Their  sum  is     l-j-2m-j-4.(l — m) =4 — 3?» — m'^,      neglecting     m^    r4961oT 

and  the  higher  powers  of  m  ;     this  agrees  with  [4961  line  2].     Lastly,  the  term  depending 
on      B;'      [4960  line  1],  is  as  in  [4961  line  2]. 


460  THEORY  OF  THE  MOON  ;  [Méc.  Ce). 

a 
[4961]       0=  ^  +  «-i.n+^^+i/^+|3''}  +  £;{l+e^+i>^+|e-|  1 

+2e+e^+3e'2-2.(5f)+5f>).^^+(l+2m-c).^^2>(l-|0\  ^ 

DLfferen-  I  ^'^^ 


liai  equa- 
tion in 

u. 


3m 


4a 


_.   -4.|i+2-+(4.ri-i).(^+^,)^4«(>-iO  4 

-.{    ,    f(l+6m+c).(l-m)+7+(-2-2m-c)a^  ^  \.e.cos(c.-«) 


2«, 


^.cos.(2w — 2mîj)  9 


3  m      l4-(l+36^+iy^-fe'^) 

1 ?B 


m 


Second.     We  shall  now  collect  together  all  the  terms  which  are  connected  with     cos.c?;. 
For  brevity,  we  shall  divide  all  the  terms  of  the  twenty   functions    [4960e]    containing 

_2 

this  quantity,  by  the  common  factor     —  - —  .  e .  cos.cv,     retaining  only  the  quotients  which 

ought  to  correspond  to  the  terms,  between  the  braces,  in  [4961  lines  3 — 7].        T/ie  same 
[49616]     process  will  be  used  with  the  other  angles  in  the  rest  of  this   note.      Then  we  have,   in 

[4866  line  2],  the  terms  2-{-e^+3e'~,  and,  in  [4901  line  3],  the  terms    —2{Bf^-\-B^J'^).^; 


m 


these  agree  with  [4961  line  3].  The  rest  of  die  quantities  depend  on  the  different  terms  of 
A,  which  we  shall  examine  according  to  the  order  of  the  indices.  The  coefficients  of 
—4^j,''>.(l— Je'-2),  in  [49111ine  2,  49>.5hne2],  are,  respectively,  +3,  and  — 2+2m, 
whose  sum  l-|-2m  is  the  same  as  in  the  two  first  terms  of  line  4  [4961]  ;  the  last  terms 
of  the  same  line  being  found,  without  any  reduction,  in  [4934  line  2].  The  coefficients  of 
^i<".e.(l-fe'2),  in  [4911  hne2,49181ine  1,  4925 line 2],  are  respectively  3,  4m,  -(2-2m-c), 
whose  sum  is  {l-\-6m-\-c')  ;  multiplying  and  dividing  this  by  1 — m,  it  produces  the 
three  first  terms  in  [4961  line  5],  connected  with  the  factor     (1 — m)  ;     the  remaining  terms 


VII.  i.-^' 9]  DIFFERENTIAL  EQUATION  IN  M.  461 

ic. {1+1(2— 19w)-e-—|e'='}  \  11 

— i(3+4m).(l+ie=— |e'=)  )  12 

,3m.)        .      „         cif,  I     \  \.e.cos.(2t) — 2mv — cv-\-a) 

_  —  J  3+c— 4m+  ^^^~"')  +24-'  J  .  e.  cos.(2«;— 2mt)+ct)— t.) 


15 

[4961] 

Q^V^ «J  „9  /  ^       Differen- 

.— ./^ l4-95;9)/_4-2J<3'  \  .e'.cos.(2v—2mv+c'mv—zi')  16    '-i?i"a- 


cootinued. 


3m ^  \  7  (4    3m) _2]^ao);^_2A'*)  i  .e'.cos.(2v—2inv—c'mv+^')  17 

'     4«,    )      2— 3m  1        a  2     (-  <. 


7M 


l+c^+i7"-+l«"+(^l"+^?04-Kl  +  2m)-^l'"    \\  18 


2 


_2 


3™        _2(l-O„0.(3-O,.).[3-m)  ,,      / 

I  2a,    \  (2-3m).(2-m)  -  ~        ^  ''      -     / 1 


"T~\  Il    /7>.'9)  I    T>l-[m\    ÏX01  '5' 


.e'.cos.  (c'mzj — ro') 


+(S;=>+Bi"»)..B';i.^ ^f— llCf— 2Cf+2a"»  I  20 


_2 
m 


+  ^.{4J^(0)+4;3,_J^(4,_|Q_J^(l)e2^_|(^^^(T)_J^(6)).g2^(   ^  21 


of  that  line  are  found  in  [4934  line  2],  without  anjr  reduction.  The  coefficients  of 
^f  e.(l— Je'2),  in  [4911  line 2,  4925  line  2],  are  3— (2— 2m+c)  =1+2/»— c,  as  in 
[496Uine3].  Tlie  coefficients  of  —è^,W)g'2;n  1-4911  jj^go^  4905  iine3,  49341ine3],  [496I6'] 
neglecting  the  factor  1 — Je'^,  are  3,  — (2 — m — c),  8;  whose  sum  is  9-\-m-\-c 
[496Iline6].  The  coefficients  of  ^.^'Jle'^,  in  [4911  line  2,  4925  line  3,  4934  line  3], 
give  3— (2— 3m— c)+8  =  9+3m+c  [4961  line  7].  Lastly,  the  terms  in  [4908  line  C] 
give,  without  reduction,     3.{Af''-{-A^p).e'^,     as  in  [4961  line  7]. 

2 
Third.     The  terms  in  [4961  lines 8 — 10]  have  the  common  factor     —  .cos.(2« — 2mv); 

and,  if  we  divide  the  corresponding  terms  of  the  functions  [4960(]  by  this  factor,  we  shall 
obtain,  in  [4870  line  1],  the  ternis     l+e^-^^y^—^e'^,     and,  in    [4879  line  9],  the  term      i^^^^'^] 
-\-2mt^  nearly;    the   sum  of  these  gives  [4901  line  8].       The  terms  [4892]inel]  are  the 
same  as  [4961  line  9]  ;  those  in  [4901  line  1]  are  the  same  as  those  depending  on  Bf\  B'-^'' 

VOL.   III.  116 


462 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[4961] 

Differen- 
tial equa- 
tion in  u 
continued. 


3  m 


3+2m-c 


^l_.jlv._A<{^ , 


^  3-t-m— c 

I        2         '2— m 


-_-|.A- 


.ee'.cos.(2t! — 2mv — cv-\-c'mv-\-zi — to') 


22 
23 


[4961  line  10].     Lastly,  the  first  term  of  aSu  [4908  line  1,  4904]  gives  the  term  depending 
on     ^f     [496  nine  10]. 


Fourth.  The  terms  in  [4961  lines  11-14]  have  the  common  factor  — .e.cos(2i--2??it'-c«). 

Dividing  the  conesponding  terms  of  the  functions  [4960e]  by  this,  we  obtain, in  [4870  lineS], 
the  terms  in  [4961  line  I2J  ;  in  [4879  line  1],  the  same  terms  as  in  [4961  line  11]  ;  in 
[4961rf]  [4892  line  2],  the  same  terms  as  [4961  line  13]  ;  in  [4901  line  6J,  the  terms  depending 
on  BJ'\  2?!,"'  [4961  line  14]  ;  lastly,  we  find,  in  [4908  lines  1,2],  the  terms  depending 
on  A^^°\     ^/i'     [4961  line  14]. 


Fifth.      The   terms   in    [4961  line  15]    have    the    factor     — ■'— .e.cos.(2u — 'imv-j-cv). 

Dividing  the  corresponding  terms  of  the  functions  [4960(>]  by  this,  we  obtain,  in  [48701ine3], 
the  terms  3-4;m  ;  and,  in  [4879  line  2],  the  term  -\-c  ;  the  suin  of  these  is  equal  to  the  three 

•  ;     and  [4908  line  1] 


[4961e]     g^g^  jg^,^^_^  ^ç  |.^ggj  j.^^g  ^gj_     ^^^.^^^  |- jgg^  line  3]  gives 


8.(1— m  ) 
2— a»i-|-c 
gives     2Af''  ;     which  are  the  remaining  terms  of  [4961  line  15]. 


Sixth.     The  terms  in  [49611inel6]  have  the  factor 


4a, 


.  e'.  cos.  {2v — 2  m  v-\-c' m  v) . 


[4961/] 


Dividing  the  corresponding  terms  of  the  functions  [4960e]   by   this,  we   obtain,  in  [4870] 

2 

hne  5,  the  term     1;     and,  in  [4892  line  5],  the  term     -\- ;     the    sum    of    these    is 

4  — ~  7tl 

,     as  in  the  first  term  of  line  16  [4961]  ;   the  term  depending  on     B[^^     is  deduced 

/£  —  111 

from  [4901  line  8],  and,  that  depending  on     ^f ,     from  [4908  line  1]. 

Seventh.  The  terms  in  [4961  line  17]  have  the  common  factor  — .c'.cos.(2t)-2m?)-c'mi;). 

Dividing    the   corresponding  terms  of  the  functions  [4960c]  by  this,  we  obtain,  in  [4870] 

line  4,  the  term     +7;     and,  in  [4892 line 4],  the  term     ^--—•,       the    sum    of    these    is 

2 — Sm 


[4961g-]     7  (4-.3nO 


2  ,     as  in  [4961  line  17]  ;  then  we  have,  in  [4901  line  9],  the  term 

and,  in  [4908  line  1],  the  term     — 2^^^>  ;     all  of  which  agree  with  [4961  line  17] 


Eiirhth.     The  terms   in   [4961  lines  18 — 20]  have  the  common  factor    — .  e'.  cos.c'mt). 

2a, 


VII.  i.  §9.]  DIFFERENTIAL  EQUATION  IN  u.  463 

-Wm-c)       7(2t3!îi)+4^n)        )  24       [4961] 
^"^   ^                  _                                        >.ce'.cos.(2t!— 2mi)— cy— c'my+ra+ro')  .'^If:',';,"^. 

I     I      /tr-\    I     ^"^ — "1 — ''    I  4  J    /l/a^  V  /^y        tion  in  u 


Dividing  the  corresponding  terms  of  the  functions  [4960(:]  by  this,  we  obtain,  in  [4866] 

line  3,  the  terms     \+e'^+ly^+%e^;     in   [4901  line  7],    the   terms      +(J5W-j-5»>)  .  L; 

m 

these  include  the  terms  of  [4961  line  18],  except  those  depending  on  •^j*"'.  The  terms 
depending  on  ^/">,  in  [49IHine 3,  49-25  line 4],  are  — Mo*»'.  j3  +  (— 2+2m)  j ,  or, 
— a.(l+2«).^,"'^  as  in  [49GI  line  18].  The  other  terms  depending  on  A^'-'\  in  [4961] 
line  19,  are  the  same  as  in  [49341ine5]  ;  observing,  that  4.(l-m)^ — 1  =(l-2m).(3-2m), 
7  1  4.(3— jn) 


[4961A] 


2— .-3;»        2— m  (2— 3;n).(2— m) 


.     The  factors  of  Af\  in  [491 1  line  3,4925  line  4], 


are,    respectively,     — |,      1  —  im;      that  in   [4934  line6]  is     — - — = — l+l^^i 

neglecting  terms  of  the  order  in-  ;  the  sum  of  these  three  terms  gives,  — 2A^^\  as  in 
[496lhnel9].  The  factors  of  ^i^',  in  the  same  three  functions  [491 1,  4925,  4934], 
and  reduced  in  the  same  manner,  are  — a,  1 — ^m,  — â-)-|-m;  whose  sum  is  — 2-f-3m, 
as  in  [4961  line  19].  The  term  depending  on  Af  [4908  line  1]  is  as  in  [4961  line  20]. 
The  remaining  terms  of  [4961  line  20]  correspond,  without  any  reduction,  to  those  in 
[4960  line  2,  4934  line  7].  Lastly,  the  terms  in  [4934  line  4],  are  the  same  as  in 
[4961  line  21]. 

Ninth.     The  terms  of  [4961  lines  22,  23]  have  the  common  factor 

2 

O  — ;" 

— — .  e  e'.  cos.(2y — 2mv — cv-\-c'mv). 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this,  we  obtain,  in  [4870  line  8], 
the  terms     |(3+2ot)  ;     in  [4879  line  5],  the   term     — ic;     in  [4892  line  8],  the  term 
-^— ^  —  ;     and,  in  [4908  lines  4,1],  the  terms     _  3^/i)_^ffi)  .     these  terms,  connected 
together  in  the  same  order,  form  the  part  in  [4961  line  22].     In  computing  the  terms  which     [4961i] 
are  multiplied  by     —A'^\     we  have,  in  [491 1  line  7],  theterm     f;     in  [4925  line  7],  the 

tenn     ihn—c);     and,  in  [4934  line  9],  the  term     -— ;     the  sum  of  these  three  parts 

is  as  in  [1961  line  23]. 

Tenth.     The  terms  of  [4961  lines  24,  25]  have  the  common  factor 

_9    - 

—  ~.ee  . COS. (2v — 2mv — cv — c'mv). 


464  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


2 

3m 

"Ô7,' 


3+2m       C  1+2OT+C 


4  c-)-?« 


26 


[4961]        ''^«,   /  +j(8)+    iiL:^^+_^    .j(;)  V  27 

2  '  (         4  c-m  )       '    f 

5-.^       (i-^m+c        4      ^     ,,,,  >.ee'.cos.(ct>-c'mt;-«+-')   _ 

l^        ^         2  c — m    )  J 


Differen- 

l!o!.°ru  /  3-2m  ,    ^,c,  ,  „  (  ]+2m+c  ,     2 

QOQtinuecI.  o 

3wt 


Dividing  the   corresponding  terms  of  the  functions  [4960e]  b)'  this,  we  obtain,  in  [4870] 
line  6,  the  terms     f(3-f-6m)  ;     in   [4879  hne  3]    the  term     — J<-  ;     in  [4892  hne  6],  the 

term     -! — *— '- —   ;     in  [4908  line  5],  the  term     f^i'*  ;     the  sum  of  these  terms  is  as  in 
'    2— 3ot — c 

[4961^]     [496nine24].     Tliere  is  also,  in  [490S  line  1],  the   term     A'p,     as  in  the   first  term  of 
[4961  line  25].     The  coefficients  of    A[^^     are  as  follows;   in  [4911  line  6],      -(-f  ;     in 

4 
[4925  line  8],    — K'"+0  !     in  [4934  line  8],     ^_g^^__^  ;     the  sum  of  these  is  the  same 

as  the  coefficient  of    A^\     in  [4961  line  25]. 

Eleventh.     The  terms  of  [4961  lines  26,  27]  have  the  common  factor 

_9 
3  HI  ,  ,  ,       I  \ 

.ee  .cos.{cv4-cmv). 

2a,  \       I  / 

Dividing  the  corresponding  terms  of  the  functions  [4960c]  b}'  this,  we  obtain  in  [4866] 
line  4,  the  terms  J(3-f2m),  as  in  the  first  part  of  line  26  [4961].  The  coefficients  of 
— ^i'>     are  as  follows;  in  [491  nine  5],     +3;     in  [4925  line  5],     J-(— 2+2m+c);     and 

in  r49341ine  111      +  ;     the  sum  of  these  three  parts  is  the  same  as  the  coefficient  of 

L  c-\-m 

[496U]     ^  (1)      [4961  Hne  26].      The    coefficients    of     A'p,      in    the  same  three    functions 

4 
[49111ine5,49251ine5,  4934rmell],  are  J,    4(-2+3/»+c),     +  ^r;;;;;  ;     whose    sum  is 

equal  to  the  coefficient  of  A'p,  in  [49611ine  27].  Lastly,  the  term  depending  on  ^f 
[4908 line  1],  is  the  same  as  in  [4961  line  27]. 

Twelfth.     The  terms  of  [4961  lines  28,  29]  have  the  common  factor 

2 

.ee  .cos.  (cv  —  c  mv). 

2a,  ^  ' 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this,  we  obtain,  in  [4866] 
lines,  the  terms  J(3— 2m),  as  in  the  first  part  of  line  28  [4961].  The  coefficient  of  ~A\'-\ 
in   [4911  line  4],  is    +f  ;     in  [4925  line  6],  is     i(— 2+2m+c)  ;     in   [4934  line  10],   is 


VII.  i.-^  9.]  DIFFERENTIAL  EQUATION  IN  u. 


+  ^'.  )  i_5^i').2::_^('0)  (  ,  e\cos.(2cv—2^)  30 

'                     '"                   ^  [4961] 

.(.2+llm+8m2)         (10  +  19m+8»l^)         n  Differon- 

q  ;;;     1                    5*                                  ~C a-j-am                 A  tion  in  u 

+  7^0                ?8^  <--^iOM<'>^^J            Le"-.cos.(2c.-2.+2m^-2«)  «— • 
V           '             2c — 2+2ot           "    '     J 


;     tlie  sum  of  these  three  parts  is  the  same  as  the  coefficient  of    Jl['\     in  [4961] 

Une  28.      In  like  manner,  the  coefficients  of    Af^,     in  the  same  hnes  of  these  three 

4  .  [4961m 

functions,  are    #,     -\-i( — 24-m+c),     -| •  ;     whose  sum  is  the  same  as  the  coefficient 

of    .4i«     [496Uine29].     Lastly,  tlie  term  of  [4908  hne  1],  depending  on     Af\     is  the 
same  as  in  [4961  line  28]. 


Thirteenth.     The  coefficients  of  -^^.62.003.2^,  in  [4866 line 6, 4901  line  10, 4908 line  1], 


v2 


are,  respectively,     1,     — -B[,"\ — 5,     — A2°^  ;     whose  sum  is  as  in  [4961  line  30]. 

m 

Fourteenth     The  terms  of  [4961  lines  31,  32]  have  the  common  factor 

_2 

— — .  e'-*.cos.(2cy — 2v+2mv). 
4a,  ' 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this  quantity,  we  obtain,  in 

[4870 line  11],  the  terms  i(6-\-l5m-\-3m^)  ;    and,  in  [4879 line  7],  the  terms  — 2c.(l+m), 

or,     J( — 4 — 4m)    nearly;    the  sum  of  these  two  expressions  is    i[2-\-llm-{-8ni^),  as  in 

the  first  term  of  [4961  line  31].      The  term  in  [4892  line  10]  is  the  same  as  the   second 

temi  of  [4961  line  31].     The  term  in  [4908  line  3],  neglecting    e'^,    is     4^/",     as  in  the 

first  term  of  [4961  hne  32]  ;  and  the  term  of  [4908  line  I],  depending  on     ./S';'",     is  the 

same  as  in  the  last  term  of  [4961  line 32].     The  term  [4934  line  12],  is  the  same  as  that 

depending  on   ./2o'"'  in  [4961  line  32].      Lastly,  [4942]  is  the  same  as  the  term  depending 

on     {A.'Y    [496Uine32]. 

3 
Fifteenth.     The  coefficients  of    ——.f.cos.2gv,     in  [48661ine7,4895,49081ine  1], 

2  2 

are,  respectively,      — Jm,     l-(-e^— ly^^    -\-2in.Al^-^;    whose  sum  is  as  in [4 961  line 33]. 

Sixteenth.     The  terms  of  [496 1  lines  34, 35]  have  the  common  factor 

2 

o  ~ 

—  .7^.cos.(2^îJ — 2v-\-2mv). 

VOL.   Ill  117 


[4961 n] 


[49610] 


[iQGip] 


466  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


tial  equa- 
tion in  u 
continued. 


[4961?] 


[4961?] 


[4961«] 


—  -J-  .  ^  \+e'^—\y^—\.M+2m.A'-p  \  .y"".  cos.  (2gv—2ê) 
■  3-\-2m—2g     {4g^—l)  (2+?») 


33 
34 


3-M  4           '4(l-m)      2g—2+2m 

+  'yi  9«(")                    s/?<ia>              }.7"~-cos.(2gv—2v+2mv—2è) 

[4961]  4a,     )    \^^i  0y/(i3)  I        ^-^a  I  ^°  S'î 

Difieren-  m                                      °             ' 


2 

.   a+g'+"+'-Y-""'>.4"-(10+5,»).<>)  37 


Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this  quantity,  we  obtain,  in 
[4870 Hne  13],  the  terms  J(3+2m)  ;  ia  [4879  hne  10],  the  term  — |^;  the  sum  of 
these  two  expressions  is  |(3-|-2m — 2^),  as  in  the  first  part  of  [4961  line  34]  ;  the 
remaining  terms  of  this  hne  are  given  in  [4892  line  12].  The  term  depending  on  B'-p 
[4901  Une  2],  that  depending  on  A^^^^  [4908  line  1],  and  that  depending  on  A^^^'^ 
[4934  line  13],  correspond,  respectively,  to  those  in  [4961  line  35]. 

n 
o  —  " 

Seventeenth.     The  coefficients  of    — ^.e'^.cos.  2c'mv,    in  [4866  line  8, 4908  line  1],  are 
f,    —A.}^^\    as  in  [4961  line  36]. 

Eighteenth.     The  terms  of  [4961  lines  37, 38]  have  the  common  factor 

—  -— —  .ey^'.cos.  (2^«  —  cv). 
Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this  quantity,  we  obtain,  in 

jg3) 

[48661ine  9],  the  term     J  ;     in  [4901  line  4],  the  term     --|-  ;     these  agree  with  the  two 

m 

first  terms  of  [4961  line  37].  The  coefficient  of  lA^\  in  [4911  line  8],  is  3+>  ;  in 
[49181ine2],  is  +3m;  in  [4925  line  9],  is  — 2^— 2— ^m+c  ;  and,  in  [4934  line  14], 
is  — 14m;  the  sum  of  these  terms  is  l-f-c — 2^ — 10??;,  as  in  [49611inéî7].  The 
coefficient  of  —^i'^\  in  [4911  line  8],  is  3+3m;  in  [4925  line  9],  is  — l+2m;  in 
[4934  hne  14]  ,  is  +8;  the  sum  of  these  is  10+5??i.  as  in  [4961  line  37].  The 
coefficient  of  .^™,  in  [49111ine  8],  is  +f;  in  [4925 line  10],  is  nearly  — f+m  ; 
and,  in  [4934  line  14],  is     +4  ;     the  sum  of  these  is     5+m,     as  in  [4961  line  38].    The 


VII.  i.  ^9.]  DIFFERENTIAL  EQUATION  IN  M.  467 

C         -2    ^  1— 2m  ;  ^" 

M,-2.).(,+2e«+2e«)+?fc5tKttf±?^n 


m"   I       (36+2l7n — 15m^)      .,,-,  ,   3(l+m)     .„o>     ,„  I       «  ,  \    ao 

rrt    ;      V — x^ ^ — y  _  J"^+  ^  ,      <•  J<'^^  e'2  )  .  -, .  COS.  («— m?;)  42 

'  a     ]  4(1 — m)  '         2(1 — m)      "  /      a'  ^ 

_(57— 33m)  ,^      ^(,5)     y^  \  ^g 

4(l_„l)         ^    -l-2-V^2       ^-"2     ^_2 


Differen- 
tial equa- 
tion in  u 
continued. 


term  +.^{,'^'  occurs  in  [4908  line  1].  Lastly,  the  terms  in  [4960  line  3],  are  the  same 
as  in  [4961  line  3SJ. 

Nineteenth.    The  terms  of  [4961  lines  39,  40]  have  the  common  factor 

—  —  .  C7^.cos.(2« — 2mt) — 2gv-\-cv). 
4a, 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this  quantity,  we  obtain,  in 
[4870  line  15],  the  terms  |+f  m  ;  in  [4879  line  12],  the  terms  — i+i"*»  the  sum  of 
these  is     \-\-2m,     as  in  the  two  first  terms  of  [4961  line  39].     The  terms  in  [4892  line  15], 

by  putting  c=:l,  ^=1,  become     - — ^ \-        „ — ,  as  in  [4961  line  39].    The  function 

2R(4)  [496K] 

[4908 line  1]  gives     2./3f  '  ;     and  [4901  line  5]  gives     —  ^  ,  as  in  [4961  lines  39,40]. 

In 

The  coefficient  of    Ai^^\     in  [491 1  line  9],  is     +3;     in    [4918  line  3],   is     +4m  ;     in 

[4925  line  11],  is     — 1;     the  sum  of  these  is     2-J-4m  =  2(1+2ot)  ;     and,  by  neglecting 

2 
m^,     it  may  be  put  under  the  form     - — ^  ;     adding  this  to  the  term  [4934  line  15],  which 

8  30 

is  nearly  equal  to     - — 5—,     the  sum  becomes  ,     as  in  [4961  line  40] . 

Twentieth.    The  terms  of  [4961  lines  41 — 43]  have  the  common  factor 

—  .  — .cos.(t) — mv).  [4961*'] 

a,    a' 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this  quantity,  we  obtain,  in 
[4872  line  1],  the  term  |  (l+2e2+2e'2);  and,  in  [4892  line  16],  the  term  -^-J|— T^ — L 
these  are  the  same  as  the  terms  of  [4961  line  41],  independent  of  [>■.    The  term  depending 


468  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

4-^:—  •  <  >  •  -,.e'.cos.Cv — mv4-c'mv — la') 

[4961]  2a,     ^  _  (5+^).^(.9,  S    "  -iô 

Differen- 

S2.  sd         U(15-8m).(l-2.)-K76-33m).Jr' )    «    ,        ^  ,46 

+  7; — ; — r— ^ •  <  >  •  --e  .COS. (v-mv-c  mv+zi'). 

2a,.(l-2'«)   ^_  5^(18)  _(i_2^).jci9)  ^    «  47 


on    fi,    ill  [49551ine  1],  is     — Ija;     and, if  we  neglect  terms  of  the  seventh  order,  we  may 

connect  it  with    the    same  factor  as    the  other   part   of    this    term,   putting   it  equal  to 

— f  f-(l+~^^+~^'^)'     ^s  '"  '^'is  fit'st  part  of  [4961hne41];    and,  we  may  incidentally 

[4961m]     remark,  that  this  factor  might  be  changed  into     l+2e^+2e'^ — fy^    [4870r'].      In  like 

manner,  the  term  depending  on  (ji,  in  [4957  line  1],  is     — «—j ;     and  may  be  connected 

with  the  corresponding  factor     l-j-fe^-j-^e'^,     and  then   it  becomes  as  in  the  last  term  of 

[49611ine41].     The  coefficient  of    — i^i'"',    in  [490Sline  l],is    +6  ;  in  [491 J  line  10], 

•  is     +9;     in  [4918  line 4],  is     12m;     and,  in  [4925  line  12],  is     — 3-j-3m  ;     the  sum  of 

these  is     12+15 m  =—^^ — ; ;       adding    this    to   the   term    in     [4934  line    161 

1 — m  '  'J 

^    '" — -  = —^ ,     it   becomes     ^ ,    as  in  [4961  line  421.  The  coefficient 

\—m  1— m  1— m  '"  -" 

14961«']    of    ^^f'.e'2,     in  [4908 line  9],  is     — |  ;     in  [4911  line  10], is     +f  ;     in  [4925  line  12], 

is     — f  ;     the  sum  of  these  is     — 3  =  — j ;  adding  this  to  the  term  in  [4934  line  16], 

6  ,  ,  3+3m  3(l+m)  •       ,       ,  r   r^or-ii 

namely ,     the  sum  becomes =  -— ,      as  m  the  last  term  oi   [4961 

^        1 — m  1 — m  1 — m  ^  •" 

line  42.     The  coefficient  of    — i-î?',     in  [4922],  is     +24;     in  [4928],  is     — 9+9w  ; 
the  sum  of  these  is     15+9m  = -r ,     neglecting    ?re-;    adding  this  to  the  term  [4946] 

— II — "—,     nearly:     the   sum   is     — ^ ,     as  in  the  first  part  of  [4961  line  43].    The 

1— m  ^  \-m 

terms  in  [4901  line  11],  are  the  same  as  those  depending  on     jB^"',     BP'    [4961  line  43]. 

Lastly,  the  coefficient  of  ix„,    in  [4913],  is  — 9;     in  [4925  line  12],  is     +9 — 9w;  and, 

in  [4934  line  16],  is    27^1— (1—mf  |  =  54m— 27m2  ;   the  sum  of  all  these  is    45m— 21m^; 

the  terms     ±9    mutually  destroy  each  other  ;  so  that  the  whole  term  becomes  of  the  order 

[4961d]     m---.K.'m,     or  of  the  seventh  order,  as  in  [4962]. 


Twenty-first.    The  terms  of  [4961  lines  44,  45]  have  the  common  factor 

2 

3m    a  .  I    /      \ 

—-  .— .e.cos.iv — mv-]-cinv). 
2a,    a 

Dividing  the  corresponding  terms  of  [4960(]  by  this  quantity,  we  obtain,  in  [4872  line  2],  the 


Vll.i.§10.]  INTEGRATION  OF  THE  EQUATION  IN  u.  469 


Wc  have  not  noticed  the  terms   multiplied  by     \ ,     because  they  mutually 
destroy  each  other,  except  in  quantities  of  the  order     m''     [4961»]. 

10.      To  integrate  this  differential  equation,  we  shall  observe,  that,  by 
noticing  only  the  parts  which  are  not  periodical,  it  gives,* 

s 

2 

We  have  denoted  this  by     M=-.(l  +  e-+i-/+[3)      [4861].       Now,    if    we      [4005] 


[4!)f)2] 


[4963] 


[49C4] 


[4961j)': 


term  -\-^;  and,  in  [4892  line  17],  the  term  f  ;  the  sum  of  these  two  terms  is  f  ,  as  in  the 
first  term  of  line  44  [4961].  The  term  depending  on  fx.,  in  [4955  line  1],  is  — |fji  ;  and, 
in  [4957  line  1],  is  — ij- ;  the  sum  of  these  two  expressions  is  — Jja,  as  in  the  second 
term  of  [4961  line  44J.  The  term  depending  on  A\l^^  [4908  line  1],  is  as  in  [4961  line  44]. 
The  coefficient  of  l^['~\  in  [490Sline7],  is  —6;  in  [4911  line  11],  is  +3;  in 
[4925  line  1.3],  is  — 1+'«  ;  and,  in  [49-34  line  17],  is  +8;  the  sum  of  all  these  is 
4+m,  as  in  [4961  line  44].  The  coefficient  of  —.^i"",  in  [4911  line  11],  is  -f-f.  in 
[49-25 line  13],  is  — 5+»»;  and,  in  [4934 line  17],  is  -f-4;  the  sum  of  all  these  is 
(5 -(-;«),     as  in  [4961  line  45]. 

Twenty-second.     The  terms  of  [496 1  lines  46,  47]  have  the  common  factor 

_2 

r — -- — -— - .  — . e  .cos.(t) — inv — cmv). 
2a,.[l — im)   a  ^  ' 

Dividing  the  corresponding  terms  of  the  functions  [4960e]  by  this,  we  obtain,  in  [4872  line  3], 

the  term    f — ^?n;    and,  in  [4892 line  18],  the  term    f;  whose  sum  is  :f(  15 — 18m),    as  in 

the  first  term  of    [4961  line  46].       The    term   in    [4955  line  2],   is    — %{\ — 2ni).v.;     in 

[4957  line i],  is     — 3(i;     whose  sum  is      — (^ — 9/«)  (^  =  — |(15 — 18m).2.a,     as  in  the 

first  part  of  line  46  [4961].     The  coefficient  of    — i^5^''\    in  [4908  line  8],  is     6— 12ot; 

in  [4911  line  12],  is     21— 42m  ,     in  [4925 line  14],  is     — 7+21/«,     neglecting     m^  ;     in    [49Glti'] 

[4934  line  13],  is     +56;     the  sum  of  these  terms  is     76 — 33m,     as  in   [4961  line  46]. 

The  coefficient  of    —A^f^,     in   [4911  line  12],  is     |— 3m  ;     in   [4918  line  5],  is     +2m, 

nearly;     in   [4925  line  14],  is     — J+m  ;     in  [4934  line  18],  is     4;     the  sum  of  these 

tenus  is     -(-5,     as  in  [4961  line  47].     Lastly,  the  coefficient  of    Af^     [4908  line  1],   is 

the  same  as  in  [4961  line  47]. 

*  (2848)     The   equation    [4961]  being   linear   in    u,     we   may  compute  the  terms 
VOL.  III.  118 


470  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4966]     neglect  the   sun's  action,  we  shall   have     -  =  -      [4864]  ;  so  that  we  may 
[4967]      suppose*     (3  =  |3"  ;     therefore,  we  shall  have. 

Equation 
between 

[4968] 


Equation  2 

between  -  -  __  q  —  o 


The  action  of  the  planets  produces  a  variation  in  the  excentricity  of  the 
earth's  orbit     e',     without  altering  its  serai-major  axis     a',    as  we  have  seen 

in  [1051',  1122,  &c.].      Therefore,  the  value  of    -      suffers  corresponding 

2 
Q  —       /  2 

[4969]      variations  on  account  of  the  termf     — - — '- —     [4968],  which  it  contains. 

4a. 


depending  on  each  angle   separately;  and,  if  we  put     A     for  the  constant  terms  of  that 
equation,  we  may  compute  the  corresponding  part  of    u     by  means  of  the  equation 

diJ  u  .       . 

[4963a]  0  =  -p-  -\-%i+A; 

which  is  evidently  satisfied  by  putting  u=  —  A.  Hence  it  follows,  that  the  constant  part 
of  M,  is  the  same  as  the  constant  part  of  [4961],  changing  the  signs  ;  this  agrees  with 
[49636]  [4964].  We  may  remark,  that  it  is  not  necessary,  in  making  this  integration,  to  add  an 
arbitrary  constant  quantity  to  — A  ;  because  it  is  implicitly  included  in  the  arbitrary 
quantity     a,     or     «,     [4860,4864]. 

[4964a]         *  (2849)     If  we  neglect  the  sun's  disturbing  force,  we  have     o,=  «     [4864]  ;   and  the 

[49646]     expression  [4964]  becomes,  in  this  case,    «=  -  .^  l+e^-f"î7^H"(3"l  •     Comparing  this  with 

the   assumed   value    of    the    constant  part    of    u,     in    the    same    hypothesis  ;     namely, 

M= -.{l+c^+iy^-f-p^     [4861],     we  get     p  =  3"     [4967];     which  is  to  be  substituted 

r4964c]     '"  t'^^  second  member  of  [4964].      We  must  also  substitute,  in  the  first  member,  the  value 

of  M  =  - .  (l+e^+iy^+p)     [4860, 4861]  ;    hence  we  get, 


[4964d] 


i.(l+e^+i7^+p)=i.(l+e2+iy^+3)-£-.(l+e3+XyS+3e'3) 

2 

+~  .  (4-3m-m-2).^i»>.(l-|e'^)-  £■ .  (5i°')V^- 
Dividing   this  by     l-{-e^-\-ly^-\-p,     and  neglecting  terms  of  the  sixth   order,  we  get  the 
value  of    -     [4968]. 

t  (2850)     The  variation  of  the  term 


Vn.i.§10.]  INTEGRATION  OF  THE  EQUATION  IN  M.  471 

Moreover,  as  the  constant  term  of  the  moon's  parallax  is  proportional  to     -, 

"        [4970] 

it  is  evident,  that  it  must  suffer  a  secular  variation  ;  but,  upon  examination,  it 
is  found  always  to  be  insensible.* 

The  part  of  it,   depending  on   cos.(cv — 3),     is  represented,  in  [4826],  by      [4971] 
-.(1+e-). COS. (ci' — zi).     If  we  substitute  it,  in  the  equation  [4961],  and  then 
compare   the  sines   and  cosines  of    cv — w,     neglecting    quantities  of  the 


d^' 


order    — -,      which   can   be  permitted,    considering    the   slowness  of  the      [4972] 

secular    variations  of  the    earth's  orbit,  we  shall  obtain    the  two  following 
equations  ;t 


_2  _9 

_3m^     [4969],     is     -|.^.e'Je'=— #."!e'.cV     [5094];  [4969a] 

therefore  the  whole  value  of    -,     is  to  this  variation,  as     1  to  —§m^.e'.Se'.     Substituting 

a 

the  values  of    m,     e'     [5117];     also     25E,     or     25e'=—t.0\l87638     [4330];     or,  in 
parts  of  the  radius,     6e'= — i.0,00000045,     nearly;     we  get 

_2 
7/Î 

—i.-.e'.Se'=t.  0,00000000006,      nearly  ;  [49696] 

which,  in  1000  years,  will  not  produce  a  single  unit  in  the  seventh  decimal  place  of  the 
moon's  distance  from  the  earth,  taken  as  the  unit  of  distance.  If  we  multiply  this 
expression  by  the  constant  term  of  the  moon's  horizontal  parallax  3424%16  [5331],  we  [4969c] 
shall  obtain  the  secular  effect  on  the  parallax,  equal  to  t0*,0000002;  which  will  not  [4969^1 
amount  to  a  second  in  a  million  of  years.  We  may  remark,  that  the  similar  term  of  [4968], 
depending  on  «4^"',  is  much  less  than  that  we  have  estimated,  as  is  evident  from  the 
smallness  of  the  value  of    A^     [5157]. 

*  (2S51)     We  shall  see,  by  the  estimate  made  in  [4987A — I],   that  this  quantity  is    |..g„^  , 
insensible. 

t  (2852)     If  we  put  for  a  moment,  for  brevity,     E=:  ,     and  use  the  values  of    [4973a] 

p,     q     [4975],    we  shall  find,  that  the  term,  depending  on     cos.(ct — w),     in  [4961],  is 

jE.(— p— 9.e'^).cos.(c« — «),     and  the  corresponding  part  of  the  equation  [4961],  is  [49736] 

0  =  ~-\-u-\-E.{—p—q.e^).cos.cv—w).  [i973c] 


472  THEORY  OF  THE  MOON;  [Méc.  Cél. 

e.(l+e^)      dd-a        ^    /  d^\  'C'     a      S 

[4974]  0  =  1  —  (^c—  — J  —p—q-e    ; 

the  quantity  — p — q.e"^,  being  supposed  equal  to  the  coefficient  of  cos.(cv-ts), 

[4975]  (l+e^).e 

in  the  differential  equation  [4961],  divided  by —  ;      where   we   must 

observe,  that  the  values  of    A^°^ ,     Jf-",     Bf\     and     Bf^      contaha  already 
[4976]     the  factor     1 — |e'^*     The  equation  [4973]  gives,  by  integration. 


If  we  consider  e,  zs,  as  variable,  and  c  constant  [4986],  we  may  satisfy  this  equation 
by  assuming  for  u,  an  expression  of  the  same  form  as  in  the  purely  elliptical  hypothesis, 
which  is     ^i  =  E.cos.{cv — ra)      [4826,4973«]  ;     substituting  this  in  [4973c],  we  get, 

ÇddE  ,  ,    ,  ^dB  A.\cas.{cv—tz)\  rf2.5cos.(cv— ej)^  ^ 

0=  ■'i-— .cos.fCT— w)+2.— . , —\-t.. — \ 

Idv^  ^  '  dv  dv  '  t/l'2  > 

[4973  e] 

-\-E.cos.{cv — ■!s)-{-E.{ — p — 5'.e'®).cos.(c(.' — is). 

Now.  by  neglecting  quantities  of  the  order  mentioned  in  [4972],  we  may  reject  ddE,  and 
we  shall  also  have, 

^^^"^^■^^  rf2.^cos.(c«— ^)^      dd^  .    .  .      (       d^Yî 


hence,  the  equation  [4973e]  becomes, 
l.W3.lO=<E.^-<c-'£).f^.,in.(..-»)  +  5E-E.(c-3V.(-l-î..-)^c«.(..-=,. 

To  satisfy  this  equation,  for  all  values  of    cv  —  w,  we  must  put  the    coefficients  of  the 
[4973/t]    sine  and  cosine  of    c«— sJ,     separately,  equal  to  zero.     The  first  of  these  conditions  gives, 
without  any  reduction,  the  equation  [4973]  ;  the  second,  divided  by    E,  gives  [4974]. 

*  (2853)  The  chief  terms  of  ^'f,  A['\  deduced  from  [4998,4999],  evidently 
contain  the  factor  1 — |e'^,  and  the  expression  of  B[''\  obtained  from  [5062], contains 
[497  a]  jg^.j^^g  ^^.jjj^  jj^g  g^i^g  factor  ;  by  this  means  it  is  introduced  into  the  equations  [5064,  5065], 
from  which  2?L-\  -B„^'  are  derived.  Hence,  it  appears,  that  the  quantities  A':,"\  A[^\ 
.fiP)  jç(3)^  which  occur  in  the  coefficient  of  cos.(cr— ra)  [4961],  contain  the  factor 
1 — |.e'2,     as  in  [4976].     We  see,  in  this  article,  [4982,&ic.],  the  importance  of  retaining 


VII.  i.  §  10.]  INTEGRATION  OF  THE  EQUATION  IN  u.  473 

I  A;.e''.(l+e2)2 


dv 


[4977] 


k  being  an  arbitrary  constant  quantity*.     Neglecting  the  square  of    g.e'^ 
we  obtain,  from  [4974]  ,t 

d'us  , ,   i<7.e'^ 

_=C-v/l-p  +  p.^=  [4978] 

Therefore,  if  we  consider    p     and     q     as  constant,  which  we  can  do  here, 
without  any  sensible  error,J  we  shall  have,  by  putting     g''=    ,~^=,  [4979] 


the  term  depending  on  e'^,  of  which  we  have  aheady  spoken  in  [4910o]  ;  since  the  secular 
inequalities  of  the  moon's  motion  depend  on  this  quantity  [4984,  &ic.]. 

*  (-2854)     We  shall  put  for  a  moment,     c — y  z=W,  and  then,  by  taking  its  differential,     [4977o] 


we  get       T^= r-      Substituting  these  values,  and  that  of    E  [4973«],  in   [4973],     [49776] 


we  obtain 

^dW        „,dE  dW      ^dE 

0  =  -^-7-^^^-lÂ^'     ''    -F  =  ^-Ë-  t4977c] 


Its  integral  is 


log.-^  =  log.E2+log.fc,      or     -  =A:.E2,  asin[4977]  ;  [4977c'] 

k  being  the  arbitrary  constant  quantity.    This  satisfies  the  first  of  the  equations  of  condition 

[49731;  and,  if  we  deduce  from  it  the  value  of     JV=c — ,      and  substitute   it  in  the 

■-         -■  dlf 

second  of  these  equations  [4974],  it  becomes, 

0=1 "^ p-n.e'^  [4977rf] 

This  might  be  satisfied,  if  all  the  elements     e,     e',    7,     &;c.  were  invariable,  by  taking  the 
arbitrary  constant  quantity     Ar,     so  as  to  correspond  to  these  elements  ;    but     e',     or     E     [4977e] 
[4330],  being  subject  to  a  secular  inequality,  it  will  produce  secular  terms  in  the  value  of  e. 
deduced  from  [4917(1]. 

t  (2855)     From  [4974],  we  have 

'  -  S  =  ^(^-^-9-^")  =  \/(l-i')-^)  +  ^-  t4978a] 

If  we  neglect  the  square  and  higher  powers  of  q.e'^,  it  becomes,  by  reduction,  as  in  [4978]. 

X  (2856)  The  quantities  p,  q  [4975],  are  functions  of  e,  y;  whose  secular  variations  are    [4979a] 
VOL.  III.  119 


474  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[4980]  ^  =  cv—v \/T^  +lq'-f<i' '•  dv  +  £  ; 

£  being  an  arbitrary  quantity*.     From  this  equation  Ave  get, 

[4981]  cos.(cz) — ui)  =  cos.|t'y/l— P — iq'.fe'^.dv — £|. 

Hence  it  follows,  in  conformity  iviih  observation,  that  the  lunar  perigee  has  a 
motion,  lohich  is  represented  by 

[4982]  (\  —  ^1  —  p).v-\-\q'.fé^.dv=^vî\oûo\\  of  the  moon's  perigee. 

This  7notion  is  not  uniform  on  account  of  the  variableness  of  e'  ;    and,  if  we 
suppose,  in  counting  from  a  given  epoch,  that   e'   is  represented  by 

[4983]  e'=£'+/t;+/D^     [4330,&c.]; 


Motion      E'  being  the  excentricity  of  the  earth's  orbit,  at  the  same  epoch,  the  motion 
of  the  perigee  ivill  bej 


of  the 

moon'â 

perigee. 


[4984]      {l—^îZ:^-{-^q'.E'^).v+lq'.E'fv^  +  ^.7'.(2E7+/2).«;3  =:  motion  of  the  moon's  perigee. 

insensible  [4937,5061];  we  may,  therefore,  consider  p  and  q  as  constant  quanthies,  in 
makbgthe  integrations. 

*  (2857)     Muhiplying  [4978]  by     civ,     integrating,  and  substituting     q'     [4979],  we 

get  [4980]  ;  whence, 
[4982a]  cv—zi  =  v\/{l—p)  —\(fft'  ^.ffo— £  ; 

whose  cosine  is  as  in  [4981].      Now,  we  have  supposed,  in  [4971, &ic.],   that     cv  —  a 
represents  the  moon's  anomaly,  and  v  the  moon's  motion  ;  their  difference  is 
[49826]  v  —  v^{\  —p)  + 1 q'.fe' ^. dv+s  ; 

so   that,   while    v     varies  from     0    to    v,    the  corresponding  motion  of  the  perigee  is 

represented  by 

[4982c]  v—v\/{l—p)+^q'.fc'^dv; 

the  integral    fe'^.dv     being  supposed  to  commence  with     t)=0.     This  is  easily  reduced 
to  the  form  [4982]. 

1(2858)     By  using  the  value  of    e'    [4983],  we  obtain, 
[4984a]   fe'^dv=^fdv.\E'^-\-2E'f.v-\-{2E'l+P).v^-\-hc.l=E'^v+E'f.v^-{-i{2E'l-lrr).v^-{-iic.; 

substituting  this  in  [4982],  we  obtain  the  expression  of  the  motion  of  the  perigee  [4984]. 
The  part  of  this  expression,  depending  on  the  first  power  of  v,  represents  the  mean  motion 
of  the  perigee,  which  we  have  put  equal  to    (1 — c).v    [4817]  ;    hence  we  get 
[49846]  {l—c).v  =  {[—\/T=^  +  hq'-E"').v. 


VII.i.>5>10.]  INTEGRATION  OF  THE  EQUATION  IN  M.  475 

This  expression  may  be  used  for  two  thousand  years  before  or  after  the  epoch 
[4984/,  /].     The  part  of  it,  included  in  the  following  formula,  expresses  the      '■        ^ 
secular  equation  of  the  motion  of  the  perigee,  which  is  decreasing  from  age 
to  age  [5232]  ; 

^q'.E'.fv''-+}^.(2E'l+f^).v^  =  secular  equation  of  the  perigee  [4984(Z].         [4985] 

The  value  of  the  constant  quantity    c    may  be  represented  by  vaiueof 

c  =  v/ÎH]^  —  I  q'.  E  ^     [4984c]  ;  [4986] 

the  angle  «  is  then  equal  to  the  constant  quantity  s,  increased  by  the  secular     [4986'] 
equation  of  the  motion  of  the  perigee  [4985].* 

Secular 
variation 

The  cxcentricity  e  of  the  lunar  orbit  is  subjected  to  a  secular  variation,  similar    "nseLib'e. 
to  that  of  the  parallax,  and  like  it  is  insensible\  [4970]  ;    these  variations      [4987] 


Dividing  by    v,    and  reducing,  we  obtain 

c=v/(l— i')-è2'.-E''     [4986].  [4984c] 

The  remaining  terms  of  [AQ8A'\,  defending  on  v^,  v^,  give  the  secidar  motio7i  [4985]  ; 
in  which  temis  of  the  order  v*  are  neglected.  To  make  a  rougli  estimate  of  the  value  of  [4984rf] 
these  neglected  ternis,  without  the  labor  of  a  direct  calculation,  we  shall  observe,  that  the 
secular  motion  of  the  perigee  is  about  three  times  as  great  as  that  of  the  moon's  mean  [4984e] 
motion  [5-235]  ;  and  this  last  quantity  is  very  nearly  represented  by  10'.j^-|-0*,018.i^ 
[5543]  ;  Î,  being  the  number  of  centuries  elapsed  from  the  epoch  of  1750.  If  we 
suppose  i  =  20,  corresponding  to  2000  years  [4984'],  these  two  terms,  of  the  orders 
t'^     v^,     respectively,  will  become     4000%     144*;     which  are  nearly  in  the  ratio  of  28     [4984g] 


[4984/] 


to  1  ;  and,  if  the  term  of  the  order  v'^  decrease  in  the  same  ratio,  it  will  become  ,    or 

28 

5%    nearly.     Now,  a  term  of  this  order,  in  the  secular  motion  of  the  moon,  or  one  of  three     [4984A] 
times  that  value  in  the  motion  of  the   perigee  [4984e],  is  wholly  undeserving  of  notice  in 
such  distant  observations;   and,  we  may,  therefore,  restrict   ourselves   to  the  terms  of  the 
orders    v^,     v^,    included  in  the  formula  [4984].     This  is  conformable  to  the  remarks  of  the     [4984i] 
author  in  [4984']. 

*  (2859)     Substituting  the  values  of   c    s^nd  fe'^dv    [4986,4934a],  in    [4980],  we 
get  as  in  [4986'], 

^=-=  +  {J9'--E'/»-+^?'.(2£'/+/2).î,3]  =  ç^  secular  equation  [4985J.  [4986o] 

t  (2860)     Using  the  value  of  q'  [4979],  we  get,  successively,  from  [4978,  4983,  4986], 
by  neglecting  terms  of  the  order  I  and  f^, 


476  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

being  proportional  to    —  ,     which  become  sensible  only   in    the    integral 

[4987']  " 

[4988]         If  we  represent  any  termwhatever  of  the  equation  [4961]  by    -.cos(m[3), 
and  denote  the  corresponding  part  of    u    by 


'-'S  =  V{l-P)-W-  e"  =  v'{l-p)-hq'-{E'^-+2Efv) 
[4987a] 

=  ^{l-p)-hq'.E'^-q'.E'fv=^C-q'.E'fv. 

Substituting  this  in  [4977],  and  neglecting     e*,     e®,     in  its  second  member,  we  get 
[49876]  e^=^.  J^^,   or     e  =  ^^^  .  (l  +  -^),     nearly  ; 

consequently,  the  secular  variation  of    e     is  represented  by 
[4987c]  ^,  =  __.1_^,    or     5e  =  e.^..; 

observing,  that,  if  we  neglect  this  secular  variation,  we  have,  very  nearly, 
[4987c']  e=— ^     [49S7J],     and     c  =  l     [4828e]. 

If  we  compare  this  with  the  chief  term  of  the  secular  motion  of  the  perigee,  which  we  shall 
[4987rf]    represent  by  fe=|ç'.jEyi;**  [4985],  we  shall  get  5e  =  -.5îï.     Now,   from  [4984e,/],  we 

have,  by  neglecting  the  signs, 

„„    .,  ,  SeO"'    .        1396000'.i  ,         ,  ,  SOm.f.t 

[4987e]  ôîJ:=30\i^     and     v= .i  = ,  nearly;     hence  &  =  ^ ; 

■■  ••  m  m         '  •"  1296000  ' 

and,  by  substituting  the  values  of    m,     e     [5117,5120],  it  becomes 
['^987/]  5e=i.  0,0000001,     nearly. 

[4987g-]    "^'^'^  •^  wholly  insensible,  since,  in  20   centuries,  which  corresponds  to    i=20,     it  only 

amounts  to  0,000002. 


If  we  retain  terms  of  the  order    v^,    in  the  calculation  of    e    [49S7J],  its  value  will  be 
[4987ft]    increased  by  a  term  of  the  form     al^.v- ■.     /^  being  of  the  same  order  as    /-,    or    I;     and 

[4987i]     this  value  of    e     gives     d-.-  =  l, .      Hence  it   appears,  that  the  quantities  neglected    in 

[4972]  are  of  the  order  f^,  or  /.  Now,  we  have  seen,  in  [4987/],  that  the  expression 
[4987ft]    of  the  part  of    (5e,     depending  on  the  first  power  of   f,     is  insensible;  and,  by  proceeding 

as  in  [4984 e — i],  it  must  be  evident,  that  these  terms  of  the  second  order  /^,  or  /,  will 
[4987i]    be  still  less,  and  may,  therefore,  be  neglected,  as  wholly  insensible,  even  in  the  most  ancient 

observations. 


VII.i.^10.]  INTEGRATION  OF  THE  EQUATION  IN  u.  477 

«  =  P.cos.(iv+^)+Q.sm.(iv+^),  [4989] 

we  shall  have  the  two  following  equations  to  determine  P  and   Q  ;* 


Q  = 


[4990] 


\     '    (h  /      dv  (Iv^  [4991] 


The   variations   of   (3    and    P    being   extremely  sloio,   and    i     very  great, 

relatively  to     —,    the  value  of     Q     is  insensible    [4990?],   and  we  have,     [4992] 
dv 

from  [4990], 


P-  —ry — :ii;^ r  ;  [4993] 


in  which  we  must  observe,  that,  as    «  +  —      is   the  coefficient  of    dv,     in 

dv 


*  (2861)     If  we  substitute  the  assumed  value  of    u     [4C89],  in 
ddu  H 

^='Â7a+"+^-'=°'-^'''+'')      [4961,4988],  [4990a] 

supposing  V,  P,  Q,  p,  to  be  variable,  it  will  become  as  in  [4990J]  ;  observing,  that 
3  is  composed  of  terms  of  w,  -a',  kc,  similar  to  [4986a]  ;  and  P,  Q,  of  terras 
e,     e',     y,     &c.,  whose  secular  variations  are  similar  to  that  in  [4987/]  ; 

To  satisfy  this  equation  for  all  values  of  the  angle  ««+(3,  we  must  put  the  coefEcients  of 
sin.(u'+p),     cos.{u-\-^),  separately,  equal  to  nothing  ;  hence  we  have, 

«=i-('>in-'?-'^-(.-+£)--*+^?- 

If  we  neglect  the  term     ddq     [4990fZ],  which  is  very  small,  as  we  shall  soon  see,  and 
VOL.  Ill  120 


478  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

the  differential   of  the  angle     rà+f3,     ive  may  suppose    (3    to  be  constant  in 
that  angle,  provided  we  take,  for    i,    the  coefficient  of   v    corresponding  to  the 
epoch  for  which  the  calculation  is  made.     Thus,  we  shall  determine  the 
[4995]      coefficients     ^f ,     A['\     Sic,  in  the  expression  of    a  ou. 

Relatively  to  the  terms,  where  the  coefficient  of    v   differs  from  unity,  by 
a  quantity  of  the  second  order,  and  which  depend  on  the  angles 

[4995'[  '2-g  V  —  c  V  —  2(3  +  *     and     v  —  mv-{-  c'mv  —  a', 

the  consideration  of  the  terms,  depending  on  the  cube  of  the  disturbing 
force,*  becomes  necessary  ;  but,  by  carrying  on  the  approximation  as  we  have 
[4996]  done,  to  quantities  of  the  fourth  order  inclusively,  the  terms  depending  on 
the  cube  of  the  disturbing  force,  which  might  become  sensible,  will  be  found 
to  be  included  in  the  preceding  results. 

This  being  premised,  if  we  substitute,  in   the  equation  [4961],  instead 
of    u,     the  following  function  ;t 


divide  the  remaining  terms  of  that  equation  by  the  coefficient  of  Q,  we  get  its  value  [4991]. 
Now,  the  secular  variations  of  3,  P,  being  of  the  order  i5ra,  Se,  fee.  [4987e,/,  &ic.], 
r4990el  t^i^y  must  be  very  small  ;  and  their  products  and  differentials,  which  occur  in  the  expression 
of  Q  [4991]  must,  therefore,  be  insensible.  Neglecting  the  quantity  Q,  and  the  second 
differential  of  P,  in  [4990c],  it  becomes  as  in  [4990]  ;  which  is  easily  reduced  to  the 
form  [4993]. 

*  (2862)     Terms  of  this  kind  have  been  noticed  in  the  differential  equation  in  ?*.     Thus, 
for  example,  the  term  multiplied  by     m  .  {A[^'')^,    in  the  coefficient  of 


[4995a] 


cos.  {2cv  —  2v-\-2mv  —  2u)     [4961  line  32], 

is  of  the  order  of  the  culte  of  the  disturbing  force;  because     m,     A'^\     are   each  of  the 
same  order  as  the  first  power  of  this  force. 


"f  (2863)  The  function  connected  with  5u  [4997],  is  the  same  as  the  value  of  m 
[4826],  augmented  by  the  term  p,  of  the  fourth  order  [4858,  &,c.],  and  taking  the 
[4997a]  coefficient  of  cos. (2^!; — 2ê),  so  as  to  include  terms  of  the  fourth  order.  These  neglected 
terms  are  easily  computed.  For,  in  the  first  place,  the  term  s*  [4812a]  introduces 
the  factor  1 — ^y^,  in  the  coefficient  of  cos.(2« — 2^)  [4816],  by  which  means  it  is 
changed  from  —if  [4816]  to  —lf.{l—ly^)  [4S12a].  The  same  change  being 
made  in  the  coefficient  of    cos.(2^« — 26)     [4819],  it  becomes,  by  using  [4S23c], 


[4997t] 


VII.i.§10.]  INTEGRATION  OF  THE  EQUATION  IN  M.  479 

1    (  1+e''+i7^+^-\-e.{l+ee).cos.(cv—^)) 
u  =  -  .{  }+6u;  [4997] 

"    (    -i-r.(\+e'-if)-cos.(2gv-2é)      S 

the  comparison  of  the  different  cosines  will  give  the  following  equations  ;* 


^     TA7''-(i-i7'')-'^os.{2gv—26)  =  -l.{\+e%iy^.(l-iy^).cos.{2gv-2è) 


=  —  -  -iy^-  (  1  -\-e^—lf).cos.  {2gv—2ô) , 


[4997c] 


as  in  [4997]. 

*  (2S64)     If  we  take   the  value  of  i,    corresponding  to  the   epoch,  as  in  [4994],  and 
neglect  the  variations  of    d^,     we  may  put  the  equation  [4990]  under  the  form 

0=11— i^.P-\-"  ;  [4998a] 


or,  as  it  may  be  written, 

0=\l-i^\.Pa+-.H.  [49986] 


Now,  muhiplying  [4989]  by    a,    and  neglecting     Q,     as  in  [4992],  we  get,  for     nu,    the 

expression     am  =  Pa.cos.(«i;-f-p),  corresponding  to  the  term     —  .cos.(Jv-|-|3)     [4988],  in    [4998c] 

the  equation  [4961].  Hence,  it  appears,  that  the  coefficient  Pa,  corresponding  to  any 
angle  ù'+p,  is  found  by  muhiplying  the  expression  [4997]  by  a,  and  substituting  the 
value     aSu     [4904].     These  values   of    Pa,     together  with   the  corresponding   ones  of 

H  [4998rf] 

—     [4961],  being  substituted,  successively,  in  [499S6],  give  the  equations  [4998 — 5017]. 

For  the   constant   part  of    au     [4997]  ;    namely,     l+e~+T7^+(3     satisfies  the  equation    [4998e] 
[4961],  as  has  been  proved  in  [4964 — 4968].     The  term  of    «2/.     [4997],  represented  by 
e.(l+e2).cos.(cî; — to),     satisfies  the  equation  [4961],  as  in  [497.3f/,  Sic.].     The  term  of    au 
[4997],  depending  on  2gv—2ê,  is   \—iil-i-e^— iy^)-{-A^'^^.y^cos.{2gv— 2è)  ;  hence, 

P«=[_i(l+e2-^y2)+^a'i,|  . 

the  corresponding  value  of    H,     [4988,  4961  line  33],  is 


[4998/] 
[4998ff] 


H=^—i\{l+e^—iy^)—i7h+2vi^i'^~^}.y^;    and    i  =  2g;  [4998A] 

substituting  these  in  [49936],  and  dividing  by     7.2,     we  get, 

=  (l-4^=').^«|^-(l+e^-i.^)  •  {  l-g'+h^  ]  +  f  A^.  Jè--2»U'^'  }  ■  [4998A] 


480  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

■l+(l+2m).e^+i?^-|e'^' 

[4998]     0  ={l-4(l-m)^}.4^'+|m.  -  .  /  -'  ^,_7; — 


— 4»'— (5<;'— 5f'>).  ^ 


2 


Equations  \  '^ 

for  the  de- 

irri.  /  ic .  { 1  +i(2— 1 9»i).e^— |e' ^ \ 

\ -|(3+4m).(l+ie^-|0+^ 

[4999]     0=ll-(2-2m-c)^i.4"+3//»'.^{         2(l+m)  , 

2— 2m— c  ■''    "^*  ^      ^ 

-i.  (  j(;)— 2  jf  )+i.  (5f -5f  ).  ^ 

[5000]     0  =  { 1— (2— 2^+0=^] .Af—irn.- .  \  3+c— 4m+/^^~"^^  +2Af'  I  ; 

[5001]    0  =  n-(2-«0'}.4''-|m'.  ^  )  i^+25f>;4+2-4f'  V  ; 

[5002]      0={l-(2-3m)^|.4^)+|m'.- Jl^M_25i"').4-24^'  >  ; 

'  7/i  _) 

,,.,3,  o=(i-„..).4"+iM.î .}  -'^:?ii:|3|f' ■4"-^.»-(^-^»')-^= 


m 


+6m.^44c>+4^='-4'^'-10.J/'^e^+|(J/'>— J/''").6^|;^ 


[4998i] 


On  account  of  the  smallness  of  the  terms    1 — g^,     -'     [4828e,  4968],  we  may  change 

the    factor     1+e"  —  {y"     into     1,     or     -     [4968],  and  then  the  equation  becomes  as  in 

[5010].  The  rest  of  the  terms  of  au  [4997]  depend  wholly  on  a&u  ;  therefore,  the  remaining 
terms  of  Pa  [4998c,  h],  will  be  represented  by  the  coefficients  of  aSu  [4904]  ;  and, 
by  takingthem  in  the  order  in  which  they  occur,  we  shall  obtain,  with  but  very  little  reduction, 
the  equations  [4998—5017]. 

f5003ol        *  (2865)     This  line  might,  for  greater  accuracy,  be  multiplied  by  the  factor  -,  like  the 


Vn.i.  §10.]  INTEGRATION  OF  THE  EQUATION  IN  u.  481 

0  =  n-(2-»l-c)^l.Jf>+|/«.-.<;        ^3^„_  4  ^^  ^;  [5004] 

^7(S+6m-c)    ,   7(2+3m)        3 
2X4  "'"2— 3nj— c~f~^     ' 

(+-'^'    1-^       2       +2-3m-cS*^' 
"     I      2  )  4  c+OT  S  ■    '    , 


2  '  (         4  c-m  )       ' 


0  =  |l_(c-m)^^4'^)_|m.-.<^  y;  [5007] 


0  =  (l_4c^).^f>+|m  .  -  .  ^  1—51"'.^-— 4'»'  S  ; 


7A 


'(2+llOT+8m2)      (l0+19m+8m-) 


[5008] 


2  2c 24-2»» 

C^*^'  ^       2c-2+2m  ^^>     ; 

0  =  jl-4-^Mf'+^  .  |â'-l-|-(-^)  +  f'«-|^'-4'''  I      [4998A;,/];        [soiO] 

S-\-2m—2g     (4g^— 1)  (2+m)      s 

2    „    \  4         ~*"4(l— m)       2g—2+2m  I 

0  =  i  1— (2§'— 2+2my-i .Jf '+^m  .  -  .  <     g^o,  q^  (,2)  }  ;       [son] 


[5012] 


other  terms  of  these  equations,  as  is  evident  by  comparing  it  with  the  corresponding  terms 
of  [4961  line  21]. 

VOL.   III.  121 


482  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5013]     o=ll-(2g-cyi,Ai-^-i^\0        '"  ^<„,^,,> 


[5014]     0  =  I  l_(2-2m-2^+c)^i  J.f'^'-fm.  -  .  j^  g^,,       ^q_^,,, 


^  _2      '     1— 2m 

m 


/|.(l-2,a).(l+2e^+2e-)+ifc?Î^Hl+t!!±2!:i)' 

r  ^  ^  ^  ^^  4(1— m) 

2^    )       (36+21m— 15?ft2)      ,,,,,,    3(1+7»)     ^,,,,     , 

[5015]    0=  1  i-(i-m)^Mr"+^.M ^4(ï=;« )— -•  ^r^+  2(ï=;^)- ^o'^  •  ^" 

[5016]      0  =  5.(1— 2f.)_^^,3,^(4+m)  _ ^(,,,_  (5+^).  j(i9)  . 

3,«'  «    (  Klâ-8m).(l-2F-)-i(76-33m).^S- 


11.     fVe  shall  noiv  take   into  consideration  the  equation   [4755].     The 
function 

which  occurs  in  this  equation,  produces  the  terms,* 


*  (2866)     Multiplying  the  equation  [4808]  by    —^5     also    [4810]    by      _-p— ^; 

**       and  taking   the  sum  of  the  products,  we  find  that  the  first  member  of  the  sum  is  equal  to 

the  function  [5018]  ;   consequently,  the   second  member   of  this   sum    will    express  the 

a 

[50196]  development  of  this  function.  The  first  terms  of  these  products,  uith  the  divisor  (l+ss)^, 
mutually  destroy  each  other.  The  remaining  terms  of  this  sum,  being  wriuen  down  in  the 
order  in  which  they  occur,  without  any  reduction,  become 


VII.i.«^  11.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  ..         483 


These  terms  are   successively  calculated  in  the  following  manner.      The 


quantity      ^   \,   ^     becomes,  by  development,^ 


[5019] 
[5020] 


1 


— 2e.s'm.  (gv-\-cv — è — ro)  I  2 

Sm'.u'^s         J'  a         ]  — 2e.sin.(^W  — C'U  — é  +  a)          f  3 
==|/».-.7./                                                                       ).  .        [5021] 

■2h^.u*        ^       a,       ^  -|-|-e'.sin.(§-îJ+c'mzj — ^ — ^')    [  4 

+  fe'.sin.  (^v — c'mv  —  è  +  Ts')    \  5 

—  fe^  sin. (2ciJ—^j;  — 2^  +  0/  6 


'.ii^  .  I  l+3.cos.(2«— 2«')  I  +  ^|g^ .{ (3-4*2).cos.(»;— i;')+5.cos.(3i.— 3«')  |  [5019c] 

If  we  neglect  the  terms  of  the  order    s^,    and  connect  together  the  other  terms,  it  becomes 
as  in  [5019]. 

*  (-2867)     LTsing   always  the  abridged  notation   [4821/],  we  have      ^s  =  ^y.s'm.gv, 
nearly  [4818].     Multiplying    this  by  the  function  [4884],  and  reducing  the  products  by     rgQgQ^n 
[18, 19]  Int.,  we  get  tlie  following  expression,  which  corresponds,  line  for  hne  with  the  four 
first  lines  of  [4884],  neglecting  terms  of  the  fourth  order  ; 

(1— Je^— i7^)-sin.^u  \  1 

3s  _  \—ie-{i—ie^—h7^)-\sin.{gv+cv)+sin.{gv—cv)U  2 

•~    "•''■  l+Ae2.|sin.(2ci;+^i;)— sin.(2cy— ^y)^  ('  3     ^^"^°*^ 

+ï7^-l — sin.^D-|-sin.3^!;)|  /  *  4 

The  coefficients  ofsin.gy,  between  the  braces,  by  connecting  the  terms,  become  l-^e^-fy^.    5 

Multiplying  together  the  two  expressions  [4866,  50206],  we  get  [5021].     The   detail  of 

the  calculation  is  in  the  following  table  [o020d — ■/]  ;  in  which  the  first  column  contains  the 

terms  between  the  braces  in  [.5020e],  the  second,  the  terms  between  the  braces  in  [4866],     [5020c] 

the  six  remaining  columns  contain  the  coefficients  between  the  braces  in  [5021],  corresponding 

to  each  of  the  smes, marked  at  the  top  of  the  columns  [5020f/].  The  sums  of  the  coefficients 

[5020/],  agree  with  the  coefficients  between  the  braces  in  [5021]. 


484 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


3m'.M'3.s 


15022] 


[5023] 


-l  vyy       H         Ç 

The  development  of    ^^^-^.cos.(2î;— 2tj'),      is  obtained  bj  multiplying 


/   o,'3 


,  ,  -     3m'. u' 

the  value  of     — — — 

and  we  shall  have,* 


cos.(2tJ— 2îj'),     which  we  have  given  in  [4870],  by 


Sm'aP.s 

2h^Aâ 


.cos.(2w — 2v')=pii 


^a 


/— I  l+2e2-|.(24-m) .y2_ 6 e'2 1  .sin (2i»-2mu-^D+a) 

+sin.(2î) — 2mv-]-gv — é) 
— 2.(l-j-OT).e.sin.(2y — 2mv-{-gv — c«— ^-j-w) 
-|-2.(l+m).e.sin.(2î) — 2mv—gv — cv-\-ô-{-a) 
+2.(1 — m).e.sm.{2v — 2mv—gv-\-cv-^ê — to) 
— 2.  (1  — m) .  e  .sin  .{2v — 2mv-^gv + cv — 6 — zs) 
— 5 .  e'.  sin.(2t) — 2mv~gv—c'7nv-\-ê-\-zi') 
+ J .  e'.sin.(2i> — 2mv-\-gv — c'mv — 6-\-zs') 
+|.e'.sin.(2« — 2mv — gv-\-c'7nv-\-ê — tn') 
— ^.f'.sin.(2y — 2mv-\-gv-\-c'mv — ê — ra') 

,  sin.(2D-2mv-2ci'+ffD4-23T-, 
-fsin(2ei)+g^-2i)+2nit)-2«-: 


l+J(10+19m+8m2)e 


2 
3 

4 
5 
6 

7 

8 

9 

10 

11 
12 


(Col.  1.) 

[5020d]         ''«'""  »''  [50206]. 


[5020e]     -ie.sm.igv+cv) 

-^e.sin.(gi; — cv) 

-le^.sm.{2cv-gv) 
[5020/] 


fCol.S.) 

Terms  of  [5021], 

having  the 

common  factor 

|.m  .;,.} 

• 

Terms  of  [4866]. 

sin.ffo 

sin{gv-\-cv) 

siii(^u — cv) 

sin.(gv-\~c'mv) 

sin.igv — c'ïfiv) 

sin.(2ci' — gv) 

l+e2+|72+fe'2 

l+le2_^j.2+3,/2 

— 3e.cos.cy 

—ie 

-ie 

-\-3e'.C0B.c'mv 

+fe' 

+¥ 

+3e2.cos.2c!; 

-ie-^ 

-\-iy^.cos.2gv 

■  -17^ 

1 

. 

-¥ 

— 3e.cos.CD 

+fe2 

1 

-ie 

— 3e.cos.e« 

+f«^ 

-ie^ 

1 

-i«^ 

Sum 

l+2Ê2-ly2f3c/2 

—2e 

—2e 

+¥ 

+¥' 

-Je^ 

3« 


(2868)     Multiplying  one  third  part  of  the  expression  of    —     [5020i],   by   that    of 


VII.i.§ll.]   DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.         485 


The  term 


33  m'.u"^.  s 


.cos.(t' — v')     [5019],  produces  the  following  ; 


[5024] 


?"''^-  .cos.(2u— 2w')     [4870] ,  we  shall  evidently  obtain  the  value  of     ^j^  .cos.{2v-2v')  ;    [5023o] 

which  we  shall  find  lo  agree  willi  the  expression  [5023],  as  will  appear  by  the    following 
calculalion.     If  any  term  of  [5020i]  be  represented  by     Say.A.sm.V,     and  any  term  of 


[4870]  by     —  .^'.cos.F,     one  third  part  of  the   product  of  these  two   terms,  or  the 

corresponding  pari  of    -|^^.cos.(2iJ— 2f'),    will  be  represented  by 

im'-.y.AA. sin.  V. cos.  V'=  | m'.  - .y. \ AA'. sin.( F+  V')+AA'.sm.(V-F') | ; 

where  the  factor     ¥  /» .  -.y     is  the  same  as  that  without  the  braces  [5023]  ;  consequently, 

the  terms  between  ihe  l)races  [5023],  must  be  represented  by  the  function 

AA.Ûn.{y-'rV')+AA!.ûxi.{V—V')  ;     or     AA'.sm.(V+V')—AA'.sm.{V'—V)  ; 

^.sin.F  rcp-cscnting  ihe  terms  hf.iwecn  theùmces  in  [5020i],  and  A'.cos.V  ihe  terms 
hetiocen  the  braces  m  [4870].  By  means  of  this  formula,  we  may  compute  the  terms 
between  ihe  braces  [5023]  in  the  following  manner. 


[50236] 

[5023c] 
[5023rf] 

[5023c] 
[5023/] 


-1— Je2_[.,y2  .|..,,2 


_3«3 


1   ! 
2 
3 
4 


Sum=— 1— 2e2-]-iy2^|„,y2^Ae'S2     5 


First.  The  coefficients  of  sin. (2c — 2mv — gv)  are  contained  in  ihe  four  lines  of  ihe 
annexed  taljle.  The  first  is  obtained  by 
combining  (1 — Ic'^ — i-/).sin.,^'-j;  [5020ilino5] 
with  (]+c2-fiy2_5.c'2).cos.(2y— 2///y)  [4870] 
line  1,  and  using  the  second  term  of  [5023c]. 
The  second  is  produced  by  sin.^«  [5()20'>  linel] 
and  i(3-}-2,w).-/2.co3.(25-w— 2i)+2»««)  [4370] 
line  1.3.  The  third  line  is  produced  by 
— ^e.s\n.(gv-]-cv)  [5020/- line2]  and  — fe.c.os.(2«; — 2mv~'rcv)  [4370  line  3].  Lastly, 
the  fourth  line  is  produced  by  — 2'^.sin.(^f-CT)  [5020iline2]  and  —§e.cos.(2v-2mv-cv) 
[4870  line  2].  The  sum  of  these  four  terras  is  given  in  line  5,  and  is  the  same  as  in 
[5023  line  1]. 

Second.  The  term  s'm.gv  [5020/;  line  1],  combined  with  cos.(2j; — 2mv)  [4870  line  1], 
and  using  the  first  of  the  forms  [5023f],  gives  [5023  line  2]. 

Tiiird.  The  terms  of  [5023  lines  3 — 6]  aie  computed  in  the  following  table;  in  which 
the  first  column  contains  the  terms  of  A.s'm.V  [50206];  the  second,  the  terms  of  -4'.cos.F' 
[4870]  ;  the  remaining  columns  contain  the  corresponding  terms  of  [5023e],  connected  with 
the  sines  of  the  angles  marked  at  the  top  of  these  columns  [50237i."]  respectively.     The 

VOL.  III.  122 


I5023g] 


[5023fe] 


[5023;] 


486 


THEORY  OF  THE  MOON  ; 


[Méc.  CéL 


[5025] 


*  3 

33  m 


16 


a,    a 


-  .7. 1  sin.(g-« — v-\-mv — '^)-\-sm..{gv-\-v — mv — è)  j . 


[5023n] 


[5024o] 


sums    of    these    terms,  in  the   bottom  line   of  the    table,    agi-ee  with  the  coefficients  in 
[5023  lines  3—6]. 


[5023i] 

(Col.  1.)    A.ain.y 
[50206]. 

(Col.  9.)        A'.cos.r' 

Corresponding  terms  or[5023e  orSOaS]. 

[4870]. 

ain  (2y-2;;iy-j-^-cu) 

sin(au-2;nu-£-o-cy) 

sin(2y-amu-^i*-|-ci') 

sin(ao— 3mc+|T)-[-o,) 

sin.g-u 

-à(3+4m)e.cos(2i>-2mt)-cw) 

(— 1— 2m).e 

(f+2»t).e 

[5023A-'] 

sin.gT 
-he.sm[gv-\-cv) 

-i(3-4m)e.cos(2«-2nw-t-cv) 
cos.(2t; — %nv) 

[h          )-e 

(J— 2m).e 

(-i+2m).e 
(-4          ).e 

-ïe.sm.{gv-cv] 

cos.(2ti — 2mv) 

(-^         ).e 

(i          )-e 

[5023^] 

Sums 

(— 2-2ni).e 

(2+2H0-e 

(2-2m).6     1     {_2+2;n).c 

Fourth.     The  term     sin.^y     [50206]   combined  with     +Je'.cos.(2»— 2?mj;  —  c'mv) 

[502:3m] 

[4370  line  4] 

gives,  by  [5023e],  the 

terms  in   [5023  lines  7, 8] 

.     In  like  manner,  the  same 

[50241] 


term     sm.gv,      being  combined  with     — |e'.cos.(2y — 2mv-\-dmv)     [4870 line  5],   gives 
[5023  lines  9, 10]. 

Fifth.     The    terms  [5023  lines  11,  12]  are  computed  in  the  following  table,  which   is 
arranged  in  the  same  manner  as  that  in  [5023A-']  ; 


(Col.  1.)     A.sm.V 
[50206]. 

sm-gv 


—  .Je.sin.(gn)-j-TO 

— ie.sin.(g-w — cv) 

— |e2.sin(2cf — gv  ) 

-\-^e^.s\T\[2cv-\-gv  ) 


(Col.  2.)  A'.'ios.V 

[4870]. 

K6-}-15m+8m2).ea.cos.(2cîj— 2î)+2mj;) 


+ie2.(3+4m 
+M(1 


— à(3-(-47»).e.cos.(2ti — 2mt) — cv) 
— à(3-[-4m).e.cos.(2y — 2mv—cv] 

cos.(2« — 2mt') 

cos.(2d — 2mi') 

Sums 

This  sum  agrees  with  the  two  last  terms  of  [5023  lines  11,  12].     The  other  terms  of  the 
development  of  the  function  [5023],  of  the  fifth  and  higher  orders,  are  neglected. 


Corresponding  terms  of  [5023e  or  5023]. 


siu.(2« — 2m« — 'icv-{-gv) 


-J-e2.(6+15m+8m2; 


ie2.(10+19Hi+8m2 


sin.  (2cu-f-£"o— Su-l-SniiT) 

+ie2.(6-|-15m+8m2) 
-H-c2.(3+4h.  ) 


+je2.(l 


+Je2.(10+19m  +  8m2) 


*  (2869)     Substituting    successively  the  values    [4937?i,  4865,  4818],    and    reducing, 
we  get, 

_2 

33m'.7<'-*.s  ,  ,  a3m'.a5.s  ,  ,         33m.o3.s 

— -r-  .cos.fu — mv)  =  — 

8a,.a'-i  ^  '  8a,.a' 


8A2.m5 


.cos.(t) — V  )  = -—  .cos.(u — mv)  =  — - — -—.cos.iv—mv) 


=  -«-~-7--sin.(ë-i'— ^)-cos.(r— miO 


33)».  a'"'.}' 

8a,.a' 

33m .  o2.7 


=  /  .{sin.(g'» — v-\-mv — â)+sin.(§-i'-}-« — mt — d)  \. 

This  last  expression  is  the  same  as  in  [5025].     It  is  of  the  fifth  order;    moreover,  the 


VII.i.§ll.]   DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.  487 

The  term  dejiending  on     cos. (3« — 3v')     is  insensible.*     We  have  noticed      [5026] 
the  two  preceding  terms  solely  on  account  of  their  having  a  little  influence 
on  the  argument  of  the  moon's  longitude,  depending  on     t' — mv. 

The  function  ^  '  7  •  (  ?    )'     contained  in  the  equation  [4755],  gives      [5027] 

the  following  term;t 

—  ^j^^.g7.cos.(gv—i).sm.(2v—2v).  [5028] 

We  shall  have  the  value  of  this  term  by  increasing,  in  the  development  of 

3m'.  u'^.  s 

— 7^ — ^.cos.(2i) — 2v')    [5023],  the  angles     gv     and    2v,    by  a  right  angle,      [5029] 

and  then  multiplying  it  by   g,    which  gives, f 


neglected  terms  of  the  siith  order,  do  not  depend  on  the  angle     v — ?»y    [4875]  ;  therefore,    r5024ci 
it  is  unnecessary  to  notice  them. 

*  (2870)     By  means  of  the  values  of  [49-37;i,  486.5,  4818],  which  are  used  in  the  last 
note,  we  find,  that  the  term  of  [5019],  depending  on     3v — 3v',     becomes 

iSiii     a     a  . 

T  'a'af''^'  ^'"•(&''~^)  ■cos.{3v—3mv).  [5026a] 

This  term  is  of  the  fifth  order,  and  depends  on  the  angles     3v — 3mvdzgv=0,     which  have 

not  been  noticed  in  these  calculations  ;  and  a  little  consideration  will  show,  that  if  we  develop 

it  so  as  to  include  terms  of  the  sixth  order,  it  will  not  produce  any  quantity  connected  with     [50266] 

the  angle     v — mv     [4875].     With  other  angles,  the  terms  of  the  sixth  order  are  usually 

neglected. 

t  (2871)      The  differential  of    [4818],  using  the   abridged   notation    [4821/],    gives 

da  gy  /ilQ\ 

■j^=g/-cos.gv;     substituting   this  m   [.5027],  It  becomes     ■^^^■^^^•g'' •i'^)  i      and,  by    [50280] 

using  [4809],  we  get  the  three  terms  in  the  second  member  of  the  following  equation  ; 

I       ds    /■:iq\      gy.cos.irv     (       3m'.u'3     .  ,        m'.it'l  '\  i   ,  ^  •    /o      o'M^ 

AT^-T.-U)=-ftr„l^-  i  -^;^  .s^n.{2v-2v)—^.[3sm.{v-v)+loM3v-3v)]^.    ^,^,,^ 

The  first  of  these  terms  is  noticed  in  [5028,  &c.],  the  others  in  [50.31,50326], 

t  (2372)     Substituting  the  value  of    s     [4818],  in  the  first  member  of  [5023],  and 
omitting    è   for  brevity  [4821/],  it  becomes     -^-7^.sin.^y.cos.(2o — 2u').      Now,  a  slight    r^Q^Qa] 

attention  will  show,  that  the  process  made  use  of  in  [5023a — n],  in  computing  [5023],  will 

be  the  same,  if  we  change    2t)    into    2î)-f90'',     and    gv    into    g'D-1-90'',    without  altering    [50295] 


488 


THEORY  OF  THE  MOON  ', 


[Méc.  Cél 


—:  a 


f  ^  14-2e2-j(2+m).y2_|e'2J  .sin(2u— 2mu— g«+â)\  1 

+sin.(2t) — 2inv-\-gv — Ô)  \  2 

— 2.(l+m).e.sin.(2u — 2mv-\-gv — cv — ^-|-to)  I  3 

-2.(l-j-m).e.sin.(2« — 2mu — gv — CT-J-^-j-ro)  /  4 

-2.(1 — m).e.sm.{2v — '2mv — gv-\-cv-[-ê — tn)  I  5 

-2.(1 — m).e.sin.(2» — 2mv-\-gv-\-cv — è — ra)  \  6 

i-|-J.e'.sin.(2y — 2m«; — gv — d mv-\-è-\-T^)  I  7 

|-l-|.e'.sin.(2« — 'imv-\-gv — cmv — ^-j-ra')  I  s 

-2-.É'.sin.(2i." — 2mv — gv-\-c'inv-\-è — -a!)  l  9 

— g.  e'.  sin.(2« — 2mv-\-gv-\-c'mv — è — ra')  I^q 


+K10+19/n+8«i2)e2. 


sm.(2v-'imv-2cv-\-gv-\-2TS-E)  1  1 1  j 


( — sjni 


i(2ci;+gT;-2«+2m!)-2^-«j5  /  ^2 


[5031] 


[5032] 


The  terms  of  the  function 


I      dsdg     |-4755  or  50286],  which  depend 


on    m'\ 


h-.v?    dv     dv 

produce  the  following  ;* 

2 

-—.-.- .  7.  { sin.(gv — v-{-mv — <)) — sm .  (gv-\-v — mv — d  j . 


[5029c] 


the  angles  mv,  cv,  c'mv  ;  by  a  melhod  of  dérivation  similar  to  that  in  [4876« — d\. 
These  changes  being  made  in  sin.^v,  cos.  (2t) — 2u'),  they  become  cos.^jj, 
—  sin.(2tr — 2v'),     respectively;  and  the  function  [5029«]  becomes 

3m'.u'3.y 


2/12.^4 


-.cos.^!;  .sin. (2 y — 2v'). 


Multiplying  this  by    g,     it  becomes  similar  to  [5028].     Hence  vs^e  see,  that  the  method 
of  derivation  [5029]  is  correct. 


[5032a] 


3);i'.«'4 


*  (2873)     The  second  term  of  [5028i]  is     —  ^7^.^7.cos.^u.sin.(v— d')  ;     and,  by 
substituting  the  values  [4937/j,  4865],  it  becomes 


o       a,  a 


which  is  easily  reduced  to  the  form  [5032],  by  using  [19]  Int.     This  term  is  of  the  fifth 
r5032tl    *^'''^^'"'  ^°^  those  of  the  dxth  may  be  neglected,  as  in  the  similar  term  [5024c].     Moreover, 
the  term  of  [50286],  depending  on  the  angle     Zv—Zv',     may  be  neglected,  for  the  same 
reasons  as  in  [5026«,  6]. 


Vll.i.^^U.]  DEVELOPxMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.  489 


[5033] 


llie  product     (  -j^  -\-s\.-—  .J  (  -~  \  .  —  contained  lu  the  equation  [4755], 
is  reduced  to* 

I .  (l-o^).r.sin.(^.-.0,/  C^)  .  ^:  .  [5034] 

1 — g-     being  of  tiie  order     m"     [4828e],  we  shall  retain,  in  this  product, 
only  the  term  depending  on     sm.(2v—2viv—gv-\-è)  ;     and  it  follows,  from 

the  preceding  development  of     Ta  --^  (  77  )  •  ~^»     ^'^'''^  ^^i^  term  is  equal  to      [5035] 

2 

—  ?iililllÇl  .^.y.  sm.(2v—2mv-gv+ê).  [5036] 

4.(1— m)       a/  ^  o    T  / 

Thus,  the  equation  [4755]  is  reduced  to  the  following  form  ;* 

Difffrcii- 
,,  liaUqua- 

n  I  I    r'  lion  111     s. 

"t^^  +  *+      '  [5037] 

1'    being  the  sum  of  the  terms  we  have  just  considered.     But,  for  greater     [5037'] 


*  (2874)     Using  the  abridgments   [4821/],  we  have     s  =  y.sm.gv     [4818];    whence 
ue  obtain  dds  ,  ,         as       • 

substituting  this  in  [5033],  it  becomes  as  in  [5034].     Now,     (1 — g^)-y     is  of  the  order 

m^y  [4828e],  orof  the  <Am/ order;  and    f— 1     [4809]  is   of  the  second  order;    hence, 

the  function  [5034]  is  of  the  fifth  order;    therefore,   we  need   only  notice  its  chief  term. 

Now,  the  chief  part  of    Tz' f  [~7~]  •  ~     [4831',  4882]  has  been  computed  in  [4885],  and    [50346] 

its  chief  term  is  r,  — "   "       ^  /«        r>       \ 

MuUiplying  this  by  the  factor     (1 — g^).y.sin.gv,     we  get  the  corresponding  part  of  [5034], 
2 
3jrt.(l— g-2)    a         .  ,^       ^     X 

2(i_,„)     ■-•7-sin.gv.cos.{2v—2mv).  [5034^] 

Reducing  this  by  [19]  Int.,  we  get  the  term  [5036],  and  another  similar  term,  depending  on 

the  angle    2v — 2mv-\-gv  ;     but  this  is  neglected,  because  it  is  of  the  ffth  order,  and  is  not    r5034(/i 

increased  by  the  integration  of  the  equation  [4755],  as  in  [4S97o,&c.]. 

*  (2875)       Substituting,    in     [4755],    the    development    of   the     terms     given     in 
[5021, 5023,  5025, 5030,  5032,  5036],  it  evidently  becomes  of  the  form  [5037].  [5037a] 

VOL.  III.  123 


490 


THEORY  OF  THE  MOON; 


[Méc.  Cél. 


accuracy,  we  imist  add  the  terms  depending  on  the  square  of  the  disturbing 
force,  ivhich  might  have  a  sensible  influence. 

3m'  m"  s 
[5036]  12.     The  term    -^„ — -     [5020]  gives,    by    its  variation,    the   following 


[5039] 


2^2.  M^ 


ones  ; 


3  m' .  u'  ^.  Ss         6  m'.  u'^.s  &u 


from  which  we  obtain  the  function,* 


h^-.u' 


*  (2376)     In  finding  the  variation  of  the  function  [5038],     s,     u,     u,     are  the  variable 

[5040a]     quantities;  but  we  may  neglect    Su',    on  account  of  its  smallness,  as  in  [4909,  4932i,&ic.]  ; 

and  the  variation  becomes  as  in  [5039].  We  shall  now  separately  compute  the  two  terms  of 

3m'.?/' 
which  this  function  is  composed.     The  first  of  these  terms      ^.-g — r-''*)     is  evidently  equal 


10  the  first  member  of  [4908/],  multiplied  by 


a.Ss  ;     and,   as  the  factor  without  the 


[5040i]     braces,  in  the  second  member  of  [4908/],  is     —  ^—  ,    the  required  function  will  evidently 

_2 

be  equal  to  the  product  of     -~.-.Ss     by    the   terms  between  the  braces  in  the  second 

member  of  [4908/].     We  shall  now  compute  this  product  in  the  following  table  ;  in  which 
the  first  column  represents  the  terms  of    &  ;     the  second,  the  terms  between  the  braces  in 
'-        '^      the  function  [4908/]  ;  and,  in  the  third  column,  the  corresponding  terms  of  the    function 
[5040]  ;  rejecting  such  terms  as  have  been  usually  neglected. 


[5040rf] 


(Col.  1.) 

Terms  of  &s  [4897]. 

Whole  value  of    6s 
B  ^^''^y.sm.{2v—2mv-gv) 


By^y-s\n.{2v-%mf-\-gv) 
B/*e'ysin  {gv — c'mv) 


(Col.  9.) 

Terms  of 
[4908/]. 

1 

— Ae.cos.cv 
-\-3c' -COS  c'tnv 
-\-5e^.cos.2cv 

all  its  terms 
-j-3e'.cosc'mt) 
-|-3e'.cosc'mi' 


(Col.  3.) 

Corresponding  terms  of  [5040]. 

o 
I  All  these  terms  must  be  multiplied  by  -^,7/i  ,-   1. 

OS     [4S97]  I 

-i-2B^^''^cy.\-s\n.{2v-2mv-gv-ci^)-s\n[2v-2mv-gv-\-ev)  \2 
-\-^B^'■''1e'y\s\n(2v-2mv-gvic'mv)+slu{2v-2mv-gv-c'mv)\3 
—^B^^'^'>e^'y.s\n{2cv-{-gv—2v-\-2mv)-{-6Lc.  4 

.  .  .  .neglected  5 

-\-iB^'-'''>e'~y.s\n.gv  6 

-{-iB^'■»\'•^y.sm.gv.  7 


This  table  contains  all  the  terms  of  the  function  [5040]  depending  on  the  coefficients  B. 
Thus,  [5040rfrine  1]  is  the  same  as  [5040 line  1];  the  terms  in  [5040rflines6,7]  are  the 
[5040e]  g^ij^g  j^g  j^  [5040  line  2];  the  terms  in  [5040rf  line  2]  are  in  [5040  lines  6,4]  ;  the  terms  in 
[5040(/line3]  are  in  [5040  lines  7,  8]  ;  lastly,  the  term  in  [5040(Z  line  4]  is  the  same  as 
in  [5040  line  9]. 


VII.  i.^  12.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.  491 

o 

—  .-.0*     [4897]  1 

+  37rt'.  -  .  j  J',"'— I J("'.e2  j  .j.sin.(2v—27nv—gv-\-'^)  3 

~   n 

— 'îiih .  -  . Bf.e,.€va..(2v — Imv — gvj^cv-\-(> — a)  4 

2      _ 

— 3  m  .  - .  J('\e7.sin.(2» — 2mv+gv — cv — (3+^)  5 

_9  «  [5040] 


Develop- 
meiil  of 
the  vuria- 
tioo[5039J. 


a-                        i      sin.(2i) — 2mv — gv+c'mv-i-è — ra')  )  7 

^      "'                  (  +sin.(2w — 2mw— ^i'— c'my+o+jj')  )  8 

+  ?^  .  -  .{5A['^—2A[''^—'jBf^l.e',.sm.{2cv+gv—2v+2mv—2^—s)  9 

2 

_j_^  .  -  .{5A['^—2Al"^\.e^}.sin.(2v—2mv—2cv+gv+2^—i).  10 

'Z       a, 


-                         Cm'.u'3.  «.(5i(         .  .  ,       , 

The  second  term  oi  [oOdyj —— ,     is  evidently  equal  to  the  product   of  the 

4     3*        '       ,  [5040/] 

first  member  of  [490S]  by     -X  —  ;     therefore,    the    development    of    this    term    will  be 

3s 
obtained  by  multiplying  the  second  member  of  [4908]  by     —     [5020i],   and  the  product 

by  ^.     This  process  is  performed  in  the  following  table  ;  in  which  the  first  column  contains 

the  terms  of     —     between  the  braces  in  [50206]  ;    the  second  column  contains  the  terms  of    L5040g-] 

[4908]   between  the  braces  ;    the   third  column,  the  corresponding  terms  of  the  function 

[5040/ or  5040],  retaining  terms  of  the  usual  forms  and  orders  ;    observing   moreover,   that 

the  product  of  the  above  factor  ^,  by  the  terms  without  the  braces  [4908,50206],  is 

~3^ 2^ .3a7=— 67.W.-     nearly.  [5040^] 


492 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


3m'. u'^.  s 


[5041] 


The  term  „    [  .  cos-  (2  v — 2î/)      [5022]    gives,    by    its    variation,  tlie 


following  terms  ;^ 


Sm'.u'^.Ss  ^       _  „        Gm'.u'^.s.iu 

COS.  (2v—2v') -j-^—^ COS.  {2v—2v') 


2   ,A 


2/i^M 


L5042] 


+ 


3m'.u'\s.W 


If.u' 


sin.(2«; — 2v')  ; 


(Col.  1.)  (Col.  a.) 

Ter  ms  of  [50206] .  Terms  of  [490S] . 


Bin.gv 


[.5040ft] 


— lie.sm.{gv-\-cv) 

— à:.sin.(gT) — cv 

siB.gv 


»4,(i'.c.cos.(2k— 2m» — cv) 
.4,'")e2.cos.(2cii— 2o-|-2mii) 
.4,t'»le2.cos.(2cw— 2i;-|-2mv) 
2.4,(»>e2.cos.(2u-2mD— 2cu) 
.4,*'i.e.cos.(2i!  — 2mv  — CD) 
.4  ^''.e.cos.(2i; — 2m« — cv) 
— 2^/i>.c3.cos.(2«— 2m«) 


(Col.  3.) 
Corresponding  terms  of  [5040]. 


.-2    a 


]• 


I  AH  these  terms  must  be  multiplied  bj 

—h^^J-^i-y-sin-i^o—^mv—gv)  I 

^A,^^^ey\sm.{Qv—2mv-\-gv—cv)—sm.[2v—^vtv—gv-cv)^2 

iJl^^ii\eSy.sin.{Qcv-\-gv—Uv-{-2mv)  3 

^^^(u  ).e^.s\n.[2v—2mv—2cv-\-gv)  4 

•.4  0)e2,,.{sin.(2ci;+gu-2u-f2mD)-|-sin{2y-2m?;-2cv+g-i')j5 

— ^.^/i\e2>.sin.(2cD+g-i!-2«4-2mt))  6 

—lJ]Me^y.  I  sm{2v—2mv-2cv-\-gv)—sin(2v—2mv—gv)l7 
Jl^('\e^.sin.{2v  —  2mv—gv).  8 


The  last  term  of  the  function  [4908],inckKlecl  in  this  table,  is  — 2./3/".e^.cos(2» — 2mv), 
'-'        •'     whicli  is  not  expressly  given  in  [4908],  though  it  is  produced  by  the  term     — 4e.cos.c«.rti5M 


[4908^  line  2],   neglecting,  for  brevity,  the  consideration  of  the  factor     —  .(1+Je'^), 

without    the    braces.       For,   by  substituting   the  term      aôu=A['\  e.cos.  (^2v — 2mv — cv) 
[4904 line  2],  and  reducing  by  [20]  Int.,  we  get, 

— 4e.cos. cv.aôu  =  — 2-4',''.e^.cos.(2f — 2»ir — 2cv) — 2A['Kc-.cos.{2v — 2m  v). 

The  first  term  of  the  second  member,  is  given  in  [4908  line  3],  but  the  second  is  not  given  ; 

[5040ft]  we  have,  however,  introduced  it,  because  it  is  necessary  to  make  the  development  [5040] 
agree  with  [5039].  This  table  contains  the  remaining  terms  of  [5040]  depending  on  A. 
Thus,  the  term  depending  on  ,3\°^  [5040  line 3]  is  the  same  as  in  [5040Aline  J].  The 
coefficient  of  .4'j".sin.(2y — 2nv — gv),  in  [5040  line  3],  is  equal  to  the  sum  of  the  two 
terms  in  [5040A  lines  7,8].  The  coefficients  of  J'^'")  [5040 lines  5,6]  are  as  in  [5040Aline2]. 

[5040/]  The  coefficient  of  ^','"  [5040  line  9]  is  the  same  as  [5040/t  line  3].  The  coefficient  of 
^('"  [5040 line  10]  is  the  same  as  [5040^  line4].  The  coefficient  of  v^J"  [50401ine9] 
is  the  same  as  the  sum  of  the  two  corresponding  terms  in  [5040Alines5,  6].  Lastly,  the 
coefficient  of  -^/'*  [5040  line  10]  is  the  same  as  the  sum  of  the  two  corresponding  terms 
in  [5040Alines5,7]. 


[5041o]         *   (2877)    In  finding  this  variation,  we  neglect  the  terms  depending  on  on',  as  in  [5040«]. 


VII.i.§12.]   DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  «.         493 
hence  results  the  function,* 

2 

4        a, 

3li    a  ^      l(l+m).Br-~Af^l.sm.(gv-cv-é+^)^  2 


-2    -a-'' 


dm      a       , 

.  -  .  e- 

4       fl.      ' 


/^  Develop- 

tioD(50'l2]. 

■  +  \Bf^+iB^^^.sm.(gv—c'mv—ê-{-z/)     ^  4     [5043] 

5 
6 

•  +  B^'l  sin.  (2v — 2mv — gv — c'ntv+6  -|-n')  -^  ^ 


^  +  \Bf^+lB'-p\.s\n.{gv—c'mv—H--J)     ^ 
)  +5',;'.  sin.  (2v—2mv—gv+c'mv-\-è—^')  Ç 

V  _1_  R(-)   çîn    f9.ii 9.WJJ) D-») /•'m1lJ-â-4-^'^  >' 


*  (2878)      If  we  multiply  the   first  member  of   [491 OA;]  by     — -^-Ss,     it   produces 

the  first  term  of  the  expression  [5042]  '^    .cos.  (2t) — 2)/).      Performing  the  same     [5043ol 

process  on  the  second  member  of  [4910A;],  we  find,  that  the  preceding  term  will  be  represented 

by  the  product   of      —.—.Ss    by  the  terms  between  the  braces  in  [491 OA:]  ;  or,  in  other    [50436] 
words,  it  will  be  found,  by  multiplying  the  expression  of    i5s     [4897]  by  the  terms  between 

2 

the  braces  in  [AdlOk],  and  theii  an?iexing  the  common  factor    —  .-     to  all   the    terms.    r5043c] 

Taking  now,  successively,  the  difl^erent  terms  of  &  [4897],  multiplying,  reducing  and 
retaining  terms  of  the  usual  forms  and  orders,  we  shall  find,  that  this  fii'st  term  of  [5042] 
produces  all  the  temis  of  [5043],  which  contain  the  symbol  B;  as  will  appear  by  the 
following  calculation. 

First.    The  product  of    J5f  .-/.sin.(2y— 2»ii;— ^u)     [4897  line  1],  by  the  first   line  of 
[4910^],  gives 

2 

'—  .-.(1+26^ — fe'2).^.sin.(4u — imv^gv) — J.sin.^-v}.  [5043rf] 

The  first  of  these  terms,  which  depends  on  the  sum  of  the  two  angles  is  neglected,  as 
usual,  because  it  produces  nothing  of  importance  ;  and  the  same  happens  with  the  sums  of 
all  the  other  angles,  which  deserve  notice,  in  this  first  term  of  [5042]  ;  provided  we 
change  the  signs  of  the  angles  in  [4910A:lines  10,  12]  ;  which  does  not  alter  their  cosines  ; 
so  that  the  term  between  the  braces,  in  [4910A;  hne  10],  may  be  put  under  the  form 
J(10-|-19?«-j-6ffl^).e^.cos.(2« — 2?wu — 2cv),Uc.      Taking,    therefore,   the  second  term  of    [5043c] 

VOL.  Ill  124 


494 


THEORY  OF  THE  MOON 


[Mtc.  Cél. 


[5043] 

continued. 


a 

a. 


e'y. 


5  ja)_2J(»5-l-Sf  ) 


—1(1 0-1-1 9m+8j«''^).51' 


(0) 


.  sill. (2c/; — gv — 2i3-f^) 


8 
9 


[5043f/],  depending  on  the  difference  of  the  angles,  and  neglecting  the  quantities  depending 
on   c^,  e'^,  it  becomes 

— '—  .  -.B^°\')'.sm.gv,     as  in  [5043  hne  1]. 

[5043e']  We  may  remark,  thai  the  circumstance  of  only  using  the  difference  of  (he  angles  in  this 
function,  enables  us  to  apply  the  priuciple  of  derivation  with  much  facility,  in  finding  the 
development  of  the  function  treated  of  in  [;j04G«,  &ic.].  The  same  term  of  [4897  line  1] 
being  combined  with  [4910/f  line  2],  produces  the  tenu  ilepending  on     Bf^     [5043  line  2]  ; 

|5043e"l  ueglecting  (?,  'f,  e'~  ;  moreover,  the  term  in  [491 0^- line  3],  gives,  in  like  manner,  the 
term  depending  on  Bf^  [5043  line  3];  the  term  in  [4910/c  line  4]  pioduces  that  in 
[5043  line  4]  :  lastly,  the  term  in  [4910/.rliue  5]  gives  that  in  [5043  line  5].  The  remaining 
terms  of  [4910/i-]  produce  quantities  of  ihe  sixth  and  higher  ortk^rs,  which  are  neglected,  with 

[5043/]    the  exception  of  that  in  [4910/j  line  10  or  5043e],  which  produces  the  term  in  [5043 line  9], 


[5043/'] 


[5043^:] 


[5043A] 


depending  on  the  angle     2cv — gv. 

Second.  The  terms  in  [4897  line  2 — 7]  produce  only  terms  of  (he  fifth  and  higher  orders 
which  may  be  neglected.  The  term  cos. (2!; — 'Hmv)  [4910/; line  1],  being  coml)ined  with 
[4897  line  8],  produces  the  term  depending  on  Bp  [-5043  line  7]  ;  with  [4S97  line  9],  it 
produces  the  term  depending  on  iî|^*  [5013  line  6]  ;  with  [4897  line  10],  it  juoduces  the 
term  depending  on  B'-p  [50431ine4]  ;  with  [4897  line  11], it  produces  the  term  depending 
on  B["''>  [5043  line  5];  with  [4897  line  12],  it  produces  the  term  depending  on  J9^"> 
[5043  line  10]  ;  lastly,  with  [4897  fine  13],  it  produces  the  term  depending  on  J5[,'2i 
[5043 line  8].  The  terms  [4910A:line4]  and  [4897line  11]  produce  the  torn  depending 
on  .Bi"»  [5043 line  1].  The  terms  [491  Ofc line  5]  and  [4897  line  10]  produce  the  term 
depending  on  B'-p  [5043  line  1].  This  includes  all  the  terms  connected  with  the  symbol  JB 
in  [5043]. 

GîJî  •  u  "tStOit 
The  second  term  of  [5042]  is j^^-^  .cos.(2i' — 2;;');     this  is  evidently   equal 


A3.  «5 


3s 


to  the  continued  product  of  the  first  member  of  [4911]  by  the  function     —  [5020i],and 


by  the  factor  |.     Now,  this  factor  f,  being  multiplied  by  the  factor    — 


4a, 


without  the 


[5043t]     braces  [4911],  and  by  the  factor  Say    [50206],  produces    — 3m. -.y.       Hence,     it    is 

evident,  that  the  second  term   of  [5042]  will  be   obtained,    by  multiplying   together  the 
functions  between  the  braces  in   [4911,50206];  then  reducing,  and  annexing  the  common 

factor    —  3  Hi .  - .  7.     This  calculation  is  made  in  the  following  table,  which  requires  no 

particular  explanation. 


VII.  1.-5.12.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.  495 


4     -«/^^    • 

e^}.  sill.  (2» — 2mv— 

-2cv+gV-\-2z:—ô). 

10 

[5043] 

concluded 

(CoM.) 

Terms  of  [50206], 
between  the  braces. 

(Col.  2.) 

Tevms  of  [-1911]. 
between  the  braces. 

(Col.  3.) 

Corresponding  terms  of  the  function  [5043]. 

r  All  Ihcso  terms  must  be  rauUiplied  by  —  S  îft^.^  .y  J  • 

sin.^-y 

.^^(I-Ae'^) 

Ai,°K{i—ie'^).sm.gv 

1 

— |c.siu.(5-«+<-«) 

A[^  c.cos.cv 
A'pe.cos.cv 

^A[^'>e.lsm.{gv—cv)+sm.{gv-\-cv)} 
.  . .  .neglected 

2 
3 

[5043ifc] 

— ie.s\n.{gv—cv) 

^3J''e.cos.tt) 

+A^(."e2.sin.(2cu— g-«) 

4 

siu-gn 

—2A^^^  e^.cos.2cv 

+  ^«'e2.sm.(2CT— ^d) 

5 

s'm.gv 

^^"'e^.cos.an' 

—iAf'>e^sia.C2cv—gv). 

6 

The  two  lower  terms  of  column  2,  lines  5,6,  correspond  in  [4911]  to 


9m 


—  j^.  {— 2.3<'i-|-.^f"'} .  e^.  COS.  2cr  ; 


4a, 

which  are  not  expressly  mentioned  in  [4911]  ;  but  are  easily  computed,  as  in  [4910Ar,  &,c.]. 
For,  the  function  [4911]  is  found,  in  [4910/],  hy  mulliplying  the  function  [4910yt]  by  the 
expression  of    2uôu,     deduced  fiom  [4904].     Now,  the  teim 

O 

Qtïî 

— .  2e.cos.(2t>— 2m?;+ci')     [4910X:  line  3], 
4a, 

being  multiplied  by  the  term     2.^/".e.co3.(22) — 2mi' — cv)     oi  2a5u  [4904],  produces  the 


term 


Ojïï 

—  ~.\-2J<i'\c\cos.2cv], 
4a,  *  ' 


which  is  used  in  [5043Â:hne  5].     In  like  manner,  the  terra 


9m 

40, 


COS.  (2v—2mv)     [4910^-  line  1], 


being  multiplied  by  the  term     2.^/"'fc2.cos.(2cD — 2v-\-2mv)     of    2aSu    [4904],  produces, 
in  [4911],  the  term       f,-^ 

-~.\A[^^'>e^.cos.2cv],     as  in  [5043^-  line  6]. 

If  we  now  compare  the  terms  of  [5043^]  with  those  in  [5043],  depending  on    A,  we  shall 

find  that  they  agree.     For,  the  term  in  [5043Arlinel],  depending  on  ^g'"',  is  the  same  as  in 

[5043  line  1];  those  in  [.5043A:line  2],  depending  onA['\  are  the  same  as  in  [5043  lines  2,3]; 

the  sum  of  those  in  [5043 lines  4. 5]  is    — 3m.  -  .7.  ^J»^/".  e^.cos.  (2c« — ^*')|)     as  in 

[5043 line  8];  lastly,  the  term  in  [5043^' line  6],  depending  on     .^/"\     is  the  same  as  in 
[5043  line  8], 


[5043i] 


[5043m] 


[5043re] 


[5043o] 


[5043/)] 


496 


THEORY  OF  THE  MOON; 


[Méc.  Cél. 


>ni                            Sm'-'u'^      lis      .     ,^       ^  ,.^        .  ,      .  .     . 

[5044]      i he  term -— ^— .  —  .sin.(2î? — 2v)*     gives,  by  its  variation,. 


[5045] 


2/Au'^ 


dv 


3m'. u'^.    d.6s     .     ,^        o  A    1   Qm'.u'^  ,     ds     .     ^^        ^  ,. 
. sm.  (2 ÎJ— 2 î;')  +  — yg— 5  .5u.-f-.sin.(2v — 2v'} 


2h\u*     dv 


dv 


,   3m.  îi^  ds  .  ,         ,_         _  ,. 
fr.u^     dv  ^  ■' 


Hence  results  the  following  function  ;t 


[5043?] 


[50466] 

[5046c] 
[5046rf] 

[5046e] 
[5046/] 


The  third  or  last  term  of  [5042] 


3m'.«'3.s.5!)' 


^      .sin. (2» — 2î)'),     is  evidently  equal  to  the 

continued  product  of  the  functions  in  the  first  members  of  [4918, 50206]  by  the  factor  ^  ; 
and,  as  this  product  gives  terms  of  the  sixth  and  higher  orders,  it  may  be  neglected  ; 
consequently,  the  value  of  the  terms  in  [5042]  is  accurately  given,  vvitliin  the  prescribed 
limits,  by  the  function  [5043]. 

*  (2879)     This  term  is  the  same  as  [5027],  substituting  [4809  line  1]  ;  its  chief  part   is 
[5045a]     computed  in   [5028,  Sic.].     Taking  the  variation   of  [5044],  and  neglecting     5m',     as  in 
[5040a, fee],  we  get  [5045]. 


[5046a]         t  (2880) 


The  first  terra  of  [5045]     —  ohi.A    •  ~T~  -sin -(21) — 2w'),  may  be  computed 


2Aa.u4       dv 

in  the  same  manner  as  the  first  term  of  [5042],  in  [504.3a — g]  ;  and,  by  this  means,  we  shall 
obtain  all  the  terms  depending  on  the  symbol  B,  in  [5046].  But,  we  may  obtain  the 
same  result  in  a  more  simple  manner,  by  the  principle  of  derivation  used  in  [4876a — d]  ; 
deducing  the  terms  of  [5046],  depending  on  any  symbol  £''"',  from  those  in  [504.3], 
depending  on  the  same  symbol,  in  the  following  manner.  If  we  denote  any  term  of  & 
[4897],  by  h  =  B'-'"''.sm.iv,  we  shall  have,  by  taking  its  differential, 
d.&s 


dv 


=  £('").  i . cos.  iv  =  jB>'1  . i .  sin.(2't)+90'')  ; 


d.is 


[5046g] 


so  that    -—      may    be  derived  from     Ss,     by  increasing   the  angle     iv     by     90'',     and 

multiplying  the  coefficient  by  i.  Moreover,  if  we  increase  2v  by  90'',  in  the  same 
manner  as  in  [4876a — cT],  the  term  cos.(2w — 2v'),  which  occurs  m  [5043a],  will  change 
into  — sin.(2« — 2v'),  as  in  [5046a].  This  increase  of  the  angles  iv  and  2v  by 
90'',  does  not  alter  the  differences  of  these  angles  in  the  terms  [5043fZ — g],  which 
depend  solely  on  these  differences  [5043e'].  Hence  it  follows,  that  the  terms  of  the 
function  [5046a],  may  be  deduced  from  the  corresponding  ones  of  [5043rt],  by  merely 
multiplying  by  the  coefficient  i,  corresponding  to  each  term  respectively  ;  or,  in  other 
words,  we  must  multiply  each  of  the  terms  of  [5043],  depending  on  B''"\  by 
the  coefficient    i,    which  corresponds  to  this  term  of    5s  =  £'"*'.  sin.  îî>     [4897].     Thus,  in 


VII.i.>5>12.]  DEVELOPMENT  OF  THE  DIFFERENTIAL  EQUATION  IN  s.         497 


3  m      a 

T  '  a. 


(2-2m-g).B[''^+i(2-3m-g).B^^'>\e'-  )  1 

}  .(l—ie").Y.s\n.{gv—ô) 


,   3iH      a 


3  m      « 


3m      a       , 
.  —  .C'y 


{{\-\-m).{1—2m—g).B^^^—A^{^\.sm.{gv—cv-è+^) 
+  { {\—vi).(2—%n—g),Bf  +  J';>  ] .  ûn.{gv-\-cv—^—^) 


(2— 3m— ^).5<"*> 


.  sin.(§-t) — c'mv — ^4-^') 


+  <  >  . sm.{gv+c'mv—(: — -a) 

-\.(2~2m—g)  B^P  S 

-\-(g — m)  .  Bf\  sin.  (2v — 2mv — gv-\-c'mv+^ — w') 

^+{g+in)  .  £f' .sin.  (2v — 2)nv — gv — c'mv+6-{-^') 


2 
3 

**      Develop- 
ment of 
the  varia- 

r       lion|50451. 


6 
7 
8 
9 
10 

11 

sin.  (2cv-gv-2-ss-^ê) 
-l(lO+\9m+8m'').(2-27n-g).B'^^^  S  12 


I [5046] 


_3m_a     mu)^^'iy^^i^^^ç2v—2mv—2cv-rgv+2-.—ê). 
4       a. 


13 


the  first  term  of  [4897  line  1],  we  have  B'-'^^  =  B'^^y,  i  =  2 — 2m — g  ;  therefore,  the 
terms  depending  on  B'^  [5043]  must  be  muhipHed  by  2 — 2m — g,  to  produce  the 
corresponding  terms  of  [5046]  ;  by  this  means,  the  term  in  [5043  Hne  1]  produces  that  in  l^OiGh] 
[5046  line  1]  ;  and  those  in  [5043  lines  2,  3, 4,  5]  give  those  in  [5046  lines  3, 4, 6,  8], 
respectively.  Again,  in  the  third  term  of  [5043  line  1],  corresponding  to  B[^'",  we  have 
i  =  2 — 2m — g — c'ni  =  2 — 3/« — g,  nearly  ;  and  this  produces  the  term  depending  on 
^(10)  [5046  line  1].  In  like  manner,  the  terms  depending  on  S','',  5™,  Bf\  B[">\ 
B^o"\  B['-\  produce  the  corresponding  ones  in  [5046]  ;  observing  always,  that  c,  g  and 
</,    are  very  nearly  equal  to  unity. 


Substituting  the  value  of 


ds 


dv 


[5028a],  in  the  second  term  of  [5045],  it  becomes, 
..5M.sin.(2y — 2v' ).gy.  cos.  gv; 

which,  by  putting    ^  =1,     is  evidently  equal  to  the  differential  of  the  first  member  of  the 
VOL.  III.  125 


[5046i] 


[5046/fc] 


498 


THEORY  OF  THE  MOON  ; 


[Méc.  Ce). 


[5047]      Lastly,    the    function       (^+s)  •  |  •/ (^)  •  %     [5033]  gives,  by  its 
variation,  the  terms* 


[5046i] 

|5046r] 
[5046m] 

[5046n] 
[5046o] 


[5046p] 


[5046g] 


ay 
function  [4931/1  or  493 Ip],  multiplied  by     —  .cos.g-w;     and,    as  the  resuhing  function  is 

composed  of  terms  o( the  JlftJi  and  higher  orders,  we  need  only  notice  the  chief  terms  of  the 
differential  of  the  function  [4931p].  These,  after  reduction,  are  contained  in  [4931p  line  6], 
and  in  [4931c,?'],  whose  differential,  divided  by  2dv,  produces  the  following  terms, 
nearly  ; 

2  9 

^  .  j  ^;"esin.CT+.4i'"e2.  sm.2cv  \  —  ~.  A'k^  sm.2cv ; 
2a^  2a, 

which  must  be  multiplied  by  the  factor  ay. cos. gv.  The  first  term  of  [5046»]  evidently 
produces  the  two  terms,  depending  on  A['-''  [5046  lines  3,  4]  ;  the  second  term  produces 
that  depending  on  -^^/'^  [5046  line  11]  ;  the  third  term  produces  that  depending  on  -4','\ 
in  [5046  line  11]. 

As  the  last  term  of  [5045]  is  very  small,  we   may  substitute   in  it  the  values   [4937?^], 
and  [4865,  5028a]  ;  by  which  means  it  becomes 

_2 

3m  .a 


-.(h'.  COS.  (2v — 2mv).  [gy.  cos.gv }  ; 

and,  as  Sv'  is  of  the  third  order  [4931a;],  the  whole  expression  must  be  of  the  sixth  or 
higher  orders.  Now,  as  it  does  not  contain  any  quantities  of  the  sixth  order,  depending  on 
the  angle  v — mv  [4875],  it  may  be  neglected  ;  therefore,  the  function  [5045]  will  be 
represented  by  the  quantities  depending  on  its  two  first  terms,  which  are  given  in  [5046]. 


[5048o]         *  (2381)      The    chief  term     ro-fC^)-^     [4809]   is  represented  by     —fW. 


dv 


Ms 


[4929«],  and  if  we  put,  in  this  case,     V^^  — ^  -j-*i  ^he  function  [5047]  will  become  of  the 


dv' 
[50486]    form    — V^  .fW.dv  ;     ivhose  variation  is  given  in  [49296],  changing  V  into   V,.     Now, 

we  see,  in  [5049],  that      Vi=  "rr  +  *     '^  o^  ^he  order  m.y,  or  of  the  third  order  ;    also 

W     [4929«],  or  its  differential  coefficient,  as  well  as     ahi,     are  of  the  second  or  a  higher 

order;  hence   it  appears,   that   all  the  terms   of  the    variation    [50486, 4929i],  excepting 

[5048c]     — 5V^.f  W.dv,     may  be    neglected,    as  of  the  seventh  or    a  higher  order.     Now,    the 

function     — fW.dv     [4929a]    is    evidently    equal  to  the   first  member  of  [4885],  and 

[5048rf]    5y^=^^_i^Ss;     hence,  the  function     —SV^.fW.dv     [5048c],     or  the  chief  part  of 


the  development  of  the  function  [5047],  will  be  represented  by 


VII.  i.  ^  13.] 


DIFFERENTIAL  EQUATION  IN  s. 


499 


_2 

3m>|  a 


y.-.|(2-2«-s-)M}.B<'».(l-je'^).< 


1— m 


.■y.sm.(gv — è) 


,  (10+19m+8m2)    „      .     ,^  ^     ,    x 


I       Develop- 
^      ment  of 
[5047]. 


The  terms  depending  on  the  cube  of  the  disturbing  force  are  insensible.* 

13.     Connecting  together  all  the  terms  of  this  development,  we  find,  that 
the  equation  [4755]  becomes. 


[5048] 


del  5  s 


OS  j  X  by  the  second  member  of  the  function  [4885]  ; 

in  which  we  must  substitute  the  value  of    5s     [4897].     Now,  the  first  term  of  this  value 

gives,  in    -^  +  ^^>     the  term     — {(2  — 2m— ^)2— 1|.  jÇ'»'.  y  .  sin.  (2d  — 2?«w— ^d)  ; 

multiplying  this  by  the  terms  in  [4885  lines  I,  10],  it  produces  the  terms  in  [5048  lines  1,2], 
respectively;  neglecting  terms  of  the  order  e^,  e'^,  in  the  factor  (l-J-2e^ — f  «'^) 
[4885 hnel].  The  factor  (2 — 2m— g)^ — 1,  being  of  the  order  m,  renders  the  term 
in  [5048 line  I]  of  the  fifth  order;  which  is  retained,  though  small,  because  the  term 
connected  with  the  angle  gv  gives  the  motion  of  the  nodes  in  [5050,  &c.]  ;  and  the  term 
in  [5048 line  2],  depending  on  2cv — gv,  is  retained  for  reasons  similar  to  those  in  [4828rf]. 
The  term  depending  on  £f^  [5048/],  being  multiplied  by  the  remaining  terms  of  [4885], 
produces  terms  of  the  sixth  and  higher  orders,  connected  with  angles  which  have  been  usually 
neglected.  The  next  term  of  Ss  [4897  line 2]  has  the  coefficient  Bi^Ky,  which  is 
marked  of  the  third  order;  but,  if  we  examine  the  value  of  B[^i  [5177],  we  shall  find 
it  to  be  so  very  small,  that  it  may  be  neglected.  The  terms  in  [4897  lines  3 — 7]  are  of 
the  fourth  order,  producing  in  [5048e]  terms  of  the  sixth  or  higher  orders,  which 
may  be  neglected.  The  terms  [4897  lines  8 — 11]  are  of  the  form  -BJ"*'.  e'y.sin.io  ; 
in  which     i     differs  from  unity,  by  a  quantity  of  the  order     m  ;     so  that     1 — i^     is  of  the 

order  m.  This  gives,  in  ~hr-\-^^i  a  term  of  the  form  Bfi.e'y.{l — i^).sin.iv, 
which  is  of  Ûie  fourth  order;  producing  only  terms  of  the  sixth  order,  in  [5048e].  In  like 
manner,  we  find,  that  the  remaining  terms  of  [4897]  may  be  neglected,  and  the  whole 
function  [5047]  is  reduced  to  the  two  small  terms  [5048]. 

*  (2882)  If  we  compare  the  value  of  n  [4902,  4961],  with  that  of  r  [5037,  5049], 
we  shall  easily  perceive,  that  the  terms  of  r  are  of  the  order  n.y  ;  and,  as  the  terms  of 
n,  depending  on  the  cube  of  the  disturbing  force,  are  of  the  fifth  or  a  higher  order 
[4995a,  4941 ,  4942,  &ic.],  the  corresponding  ones  of  r  must  be  of  the  sixth  or  of  a  higher 
order,  which  may  be  neglected. 


[5048e] 

[5048/] 
[5048ff] 


[5048A] 


[5048t] 


[5048/t] 


[5048^] 


600  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

av  a    ]  [ 

'  i^^,l3Sm—g\.B'-^''\e'^+i.(3—m—g).BfKe'A  3 

[5049]  (L") 

—  fîw.-.  )     /i_  ''^  V  .7.sin.(2t) — 2mt) — gv-\-^) 

lion  in  s.'_  fl^ 

+  fm".  -.\Bf^—2+(l—m).(3—2m—g).Bl'^l.e).sm.(gv-i-cv—c—z,)  8 

*"/ 

+  |m'.-  .{5f' — 2— 2J',"+(l+m).(3— 2m— ^).£f' }.ev.sin.(^î;— cf— «+^)  9 

+  |m'.  -.  S  (1+^).(1— m)— 25<")+5(^)  \ .€y.sm.(2v—2mv—gv+cv+ê-^)    10 
"'/ 

+  |OT  .  -{(g—l).(l+m)^Bf^—2A'^^'>\.ey.sm.(2v—2mv+gv—cv—ê+m)       1 1 


*  (2883)     The  equation  [5049]  is  the  same  as  [5037],  taking  for-   r    all  the  terms  we 

[5049a]     havecomputedinthe!;e»functions[5021,50-23,5025,5030,5032,5036,5040,5043,5046,5048]. 

In  finding  the  sum  of  these  terms,  we  shall  proceed  as  in  note  2847  [4960e,  &c.],  taking  the 

quantities  depending  on  each  angle  separately,  in  the  order  in  which  they  occur  in  [5049]  ; 

after  dividing  them  by  the  factor  which  is  common  to  all  the  terms  as  in  [4961i]. 

First.     The  terms  depending  on     sin.^u     [5049  lines  1  —  4]    have  the  common  factor 

fm  .— .y.sin.^i)  ;     and  if  we  divide  all  the  terms  of  the  functions  [5049a],  depending  on  this 

angle,  by  this  factor,  we  shall  obtain  in  [5021  linel]  the  terms  l-j-2e^ — 17^+1^'^  as  in 
[5049 line  1].  The  terms  in  [5040  line  2]  are  the  same  as  in  [50491ine4].  The coefScient 
of    £<«'.(!— ie'2),     in    [5043  linel],  is     —i;     in    [5046  line   1],  is    —^{2—2m—g); 

their  sum  is  _i,^s-2.n-g)  =  -i.(t^pyi-m). 

[50496]     Lastly,  the  term  in  [5048  line  1]  is 


VlI.i.>^U3.]  DIFFERENTIAL  EQUATION  IN  «.  501 

4.|j|.!L.  ?  (1  _l_o-).(l  +m)+5f  +2J;»-2Bî''> }  .ey.sin.(2v-2mv~gv-cv+ô+z,)    12 

-j-llïï^.{S+2Bf^—i(3-2m-g).BfW^3-m-g).B['^].e'y.sm.(gv-c'mv--è+z,')  14   ^.^^^^^^_ , 

/  t  lal  eijua- 

tion  in     s^ 
o  ~  concluded. 

+fm .-.  ^  J  (1  +^)  +2Sf  >+35f^— (  1  +g  —m)  .BW }  .e'y.sm.{2v—2mv—gv-\-dmv-{-ô-zi')  1 5 

4-f  Hl°.-.  {2jB<,'«-  J(l+^)+3-Bf°i— (1  +^+?»)Bi"}  .eV.sm.(2z>— 2mu— 5-i;-c'm«+â+w')  i6 

^  2Bi,'"— 5— 10.3«+4^ii»— (3— 2m— 2c+g').jB<''i  ^  17 

+?M.-.  /      ^o  o  Wo  9«,  „-\a  T  î  1  /  .e^y.sin(2cj;— e-î) — 2a+ra) 

3„   (2B'r-^+i{l-g).{lO+l9m+8nv')^  19 

-f-f  m .-.  ■?  >  .eV.sin.(2y — Smc — 2cv-\-gv-\-2TS — é) 

2^   ri.(10+19m+8m2)_|_2J5;'3)    i  21 

-|-|w .-.  <  ?  •  e^7'  sin.  (2cî)-}-,§''' — 2t)-|-2mr — 2a — fl) 

"'  ( +10^<'i— 4^.""— 5B<")     )  22 

^  a     (  )     1 

+|-m.-.  ]  3+2i?^">  S  .  -.7.sin.(^«— î;+wî2; — ê)  23 

+T»î--  •  \  |+2Sr  f  •  ^,-7.sin.(^t)+î;— m?;— ^).  24 

adding  this  to  the  sum  of  the  two  preceding  terms,  it  becomes 

-^  {T^rT-)  ■  (^  +  '")  '  [50496'] 

which  is  the  same  as  the  coefBcient  of  B'p  [5049  hne  2].  The  term  depending  on  ./^^'" 
[5043nnel],  is  the  same  as  in[5049hne2].  Tiie  coefficient  of  B[^\e'^l—je^),  in 
[5043  line  1],  is  i;  in  [5046  Une  2],  is  a(2 — m — g);  wliose  sum  is  ^{3 — m — g),  as  in 
[5049  hne  3].  The  coefficient  of  B['°\e'^.(l—ie%  in  [5043  Hne  1],  is  —J;  and,  in 
[5046  hne  1],  is  —l(2—3m—g);  their  sum  is  — J(3— 3?«— ^),  as  in  [5049  line  3]. 
The  term  depending  on     A'-°''     [5043  line  1],  is  the  same  as  in  [5049  line  2]. 

Second.     The  terms  in  [5049 lines 5, 61  have  the  common  factor  „,„  , 

ji    a  [50i9c] 

—  ^WL  .  -  .  7 .  sin.  (2v — 2mv — gv)  ; 

VOL.  lit  126 


502  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5049]  14,     In  finding  the  integral  of  the  equation  [5049],  we  must  proceed  in 


[5049c'] 


[5049d] 


and,  if  we  divide  the  corresponding  terms  of  the  functions  [5049a]  by  this  factor,  we  shall 
obtain,  in  [5023  line  1],  the  terms  l+2e«— i(2+m)  .7^— |e'2  ;  and,  in  [5030  line  1],  the 
same  terms,  niuhiplied  by  g;  their  sum  is  the  same  as  in  [5049  line  5].  The  expression 
[5036]  is  the  same  as  the  first  term  in  [5049  line  6].  The  terms  depending  on  A'^\  A'^'> 
[5040 line  3],  are  the  same  as  in  [5049  line  6].  The  terms  in  [5040 Hire  1,4897  line  1] 
give  the  term  depending  on     &l^'>     [50491ine6]. 

Third.     Of  the  three  terms   in  [5049  line  7],  the  first  is  found  in  [5023  line  2];   the 
second,  in  [5030  line  QJ;  and  the  third,  in  [5040  line  1,4897  line  2]. 

Fourth.     The  terms  in  [5049  line  8]  have  the  common  factor 

J  »rt  .  —  .  e 7 .  sm. {g v-f-cv)  ; 

and,  if  we  divide  the  corresponding  terms  of  the  functions  [5049a]  by  this  factor,  we  shall 
get,  in  [5021  line  2],  the  term  — 2  ;  m  [5040  line  1],  the  term  JB!,-'  ;  as  in  the  second 
and  first  terms  of  [5049  lines].  The  coefficient  of  (l—m).Bf,  in  [5043  line  3],  is  1; 
and  in  [5046  line  4],  is  2 — 2m — g  ;  whose  sum  is  3 — 2m— g,  as  in  [5049  line  8].  Lastly, 
tlie  terms  depending  on     .^/''  [5043  line  3,  5046  hne  4]  mutually  destroy  each  other. 

Fifth.     The  terms  in  [5049  hne  9]  have  the  common  factor 

f  m  .  —  .  ey  .sm.[gv  —  cv)  ; 

and,  if  we  divide  the  corresponding  terms  of  the  functions  [5049a]  by  it,  we  shall  obtain,  in 
[5021  line  3],  the  term  — 2;  in  [5040  line  1],  the  term  B':p  ;  as  in  the  two  first  terms  of 
[5049e]  ^g^j^g  jj^g  g-j_  rpjjg  coefficient  of  (l+m).Bf ,  in  [5043  line  2],  is  1  ;  and,  in  [5046  lin63], 
is  (2 — 2m — g)  ;  whose  sum  is  (3 — 2»! — g),  as  in  [5049 line  9].  Lastly,  the  terms 
depending  on    A['  >    [5043  line  2, 5046  line  3] ,  being  added,  give     -2^<  ■'    [5049  line  9] . 

Sixth.     The  common  factor  of  the  terms  in  [5049  line  10]  is 

f  wi  .  —.e'y.s}n.(2v — 2mv — gv-\-cv). 

The  term  connected  with  it,  in  [5023 line  5],  is  1 — m  ;  in  [50301ine5],  is  ^(1 — m)  ; 
whose  sum  is  (1+^)'(1 — "Oj  3s  in  the  first  part  of  [5049  line  10]  ;  [5040  line  4]  gives 
— 2Bf';     and  [5040  line  1]  gives     B'-^'' ;     as  in  [5049 line  10].      In  the  same  manner  we 

[5049/]    obtain  the  terms   connected   with      %ni .  -  .ey.s'm.  (2v — 2mv-\-gv — cv)  ;     namely,     in 

[50231ine3],  — (l+»0;  in  [5030  line  3],  g{l+m);  whose  sum  is  {g — l).(l-|-m); 
in  [5040  line  5],  the  term  — 2^/"  ;  and,  in  [5040  line  1],  the  term  Bf''  ;  all  these  agree 
with  [5049  line  11]. 


VII.  i.  §  14.] 


INTEGRATION  OF  THE  EQUATION  IN  s. 


603 


a   similar  manner  to  that  in  [4971,  &c.].      We   shall,   therefore,   suppose     [5049' 


Seventh.     The  common  factor  of  the  terms  in  [5049  line  12]  is 

§711  .  —  .  cy.  sm.(2u — 2mi' — gv — cv). 
"■1 

The  term  connected  with  it,  in  [5023 hne 4],  is     (l-{-m);     in   [5030hne4],  is     g{l-^m)  ;     [5049^] 
whose  sum  is  {l-\-g).{l+m);  in  [5040  hne6],  is  — 2(5^°'— ^i'>)  ;  and,  in  [5040 hne  1], 
is     Bf\     These  agree  with  [5049  hne  12]. 

Eighth.     The  terms  connected  with  the  common  factor 


f  m 


-  .  ey.  sin.  (2v — 2mv-\-gv-\-cv), 


are  as  follows.     In  [5023  line  6],     — (1 — m);    in  [5030  hne  6],    ^(1 — m)  ;     whose  sum     [5049;»] 
(^ — l)-{l — m)     is  of  the  second  order  [4828c]  ;  or,  of  the  sixth  order  in  [5049]  ;  and,  as 
this  is  not  increased  by  the  integration  [4897o,  Sic],  it  is  neglected. 

JVinth.     The  common  factor  of  the  terms  in  [5049  line  13]  is 

.e'y.sin.  {gv~\-c'mv). 
The  term  connected  with  h,  in  [5021  line  4],  is     3;     in  [5040  line  1],  is     25f>  ; 


_-  a 
*'"     a. 


as  m 


1  . 

2  5 


[5049t-] 


the  two  first  terms  of  [5049]ine  13].  The  coefficient  of  B'f\  in  [5043  line  5],  is 
in  [.5046 line  8],  is  ^(2 — 2m— g);  whose  sum  is  ^(3 — 2m— g),  as  in  [5049 line  13]. 
The  coefficient  of  ^i'"' ,  in  [5043  line  5],  is  —1  ;  in  [5046  line  7]  is  — (2— 3ot— ^)  ; 
whose  sum  is     — (3 — 3;n — g),     as  in  [5049  line  13]. 

Tenth.     The  common  factor  of  the  terms  in  [5049  line  14]  is 

^iit  .-  .  e'y.sin.^gv  —  c'mv). 

The  term  connected  with  it,  in  [5021  line  5],  is     3;     in  [5045  line  1],  is     2B[^\     as  in  the 
two  first  terms  of  [5049  line  13].     The  coefficient  of    Bf\     in  [5043 line  4],  is     — J;    in 
[-5046 line  6],  is     —i{2—2m—g);     whose  sum  is     — J(3— 2ot— ^),  as  in  [.50491ine  14],    [5049A] 
The  coefficient  of    Bf\     in  [5043 line 4],  is     —1;     in  [5046 line 5], is    —(2—m—g); 
whose  sum  is     — (3 — m — g),     as  in  [5049  line  14]. 

Eleventh.     The  common  factor  of  the  terms  in  [5049  line  15]  is 

f  m  .  — .e'y.sm.{2v—2mv — gv-\-c'mv). 

The  term  connected  with  it,  in  [5023  line  9],  is  i;  in  [50301ine9],  is  ig;  in  [5040  line  1], 
is  25^»;  in  [5040  line  7],  is  36,°';  in  [5043  line  6],  is  — iî^^^  ;  and,  in  [5046  hne9], 
is    — {g — m).B'f''.     These  terms,  taken  in  the  same  order,  are  as  in  [5049  line  15]. 


504  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5049"']    y  and  ê  to  be  variable  ;  in  consequence  of  the  variation  of  the  excentricity 

Twelfth.     The  common  factor  of  the  terms  in  [5049  fine  16]  is 
I  m  .—.e'7.sm.{2v~2mv—gv  —  c'mv). 
The  term  connected  with  it,  in  [5023 line 7],  is     — J;     in  [5030 Une 7],  is     — J^;    whose 


[5049m] 


[5049re] 


[5049o] 


[5049p] 


sum  is  — i{^-\-g)>  as  in  the  second  term  of  [5049 line  16].  The  term,  in  [5040  line  1], 
is  2B<"";  in  [5040  line  8],  is  3Bf;  as  in  the  first  and  third  terms  of  [5049  line  16]. 
Lastly,  the  coefScient  of  B^p,  in  [5043  line  7],  is  — 1;  and,  in  [5046  line  10],  is 
—  (S'\'^)  5     whose  sum  is    — (l+â"+"')'     ^'  '"  ''^^  '''^'^  '^•''^  °f  [5049  line  16]. 


Thirteenth.     The  term  connected  with  the  common  factor 

a 


^  m  .  —  .  c'  y .  sin.  (2y — 2iiiv-{-gv — c'mv), 

in  [5023  line  8],     J;     and,  in  [5030  line  8],  is     —ig;     whose  sum     i{l—g)     is  of  the 

order     ni^     [4828e],  producing  terms  of  the  sixth  order,  which  may  be  neglected.      In  like 

_-  a 
manner,  the  terms  connected  with  the  factor     f  m  .  - .  e'y. sin.  (2  v — 2 m  v-\-g  v-\-c'm  v),      in 

[5023  line  10],  is  — J;  and,  in  [5030  line  10],  is  -}-ig  ;  whose  sum  — h{^—g)^ 
is  of  the  second  order,  producing  terms  of  the  sixth  order,  in  [5049],  which  may  be 
neglected. 

Fourteenth.     The  common  factor  of  the  terms  in  [5049  lines  17, 18]  is 

_2  a 
f  w  .  —  .  e^y .  sin.  (2cv — gv). 

The  term  connected  with  it,  in  [5021  line  6],  is  —5  ;  in  [5040  line  1],  is  25^"'  ;  as  in 
the  two  first  terms  of  [5049  line  17].  The  coefficient  of  ^/'^  in  [5043  line  8],  is  —5  ; 
in  [5046  line  11],  is  — 5;  whose  sum  is  — 10,  as  in  [5049 line  17].  The  coefficient 
of  A[''\  in  [5043  hne  8],  is  +2,  in  [5046 line  11],  is  +2;  whose  sum  is  +4, 
as  [5049 line  17].  The  coefficient  of  JS'/=',  in  [5043  line  8],  is  —1;  in  [5046  line  11], 
is  —(^2  —  2m—2c-{-g);  whose  sum  is  — (3— 2m— 2c+^-),  as  in  [5049 line  17].  The 
coefficient  of  {l0-{-l9m +8m^).B'f\  in  [50431ine9],  is  J;  in  [5046 line  12],  is 
l[2—2m—g);  whose  sum  is  j(3 — 2m — g),  as  in  the  first  term  of  [5049  line  18]  ;  the 
remaining  term  is  as  in  [5048  line  2],  neglecting  the  factor  (1  —  fe'^). 

Fifteenth.     The  common  factor  of  the  terms  in  [5049  lines  19,20]  is 

-  a 
x  m  .  — .  e"-/-sin.(2i! — 2mv  —  2cv-{-i!;v). 
a 

The  term  connected  with  it,  in  [5040 line  1],  is  22?,'=',  as  in  the  first  term  of  [5049  line  19]. 

The  coefficient  of    i{l0-{-l9m+8m^),     in  [5023  line  11],  is     1;     and,   in  [5030 line  11], 

is     — g-     whose  sum  is     (1— 4r),     as  in  the  second  term  of  [5049 line  19].     The  terms 

depending  on     ^i'\     .^i"^     [5040  line  10],  are  as  in  [5049  line  20].     The  coefficient  of 


VII.  i.  §  14.]  INTEGRATION  OF  THE  EQUATION  IN  s.  505 

of  the  earth's  orbit.     Then,  by  substituting,  for     s,     the  expression  [4897z] 

s  =  y.  sin.(gv—ù)+5s,  [5050] 

and  comparing  at  first,  the  sines  and  cosines  of    gv — ^,     we  shall  obtain  the 
two  following  equations  ;* 


[5049g] 


^J''  [5043  line  10],  is  — 1;  and  that  in  [5046  line  13],  is  also  — 1;  whose  sum  — 2, 
is  asm  [5049  line  20]. 

Sixteenth.     The  common  factor  of  the  terms  in  [5049  lines  21,  22]  is 

f  TO  .  — .  e-'y.sm.(2cv-\-gv — '■2v-\-2mv). 

This  is  multiplied  by  the  factor  i(10-}-l9m-j-8m^),  in  [5023  line  12]  ;  and  also,  in 
[5030 line  12];  their  sum  is  as  in  the  first  term  of  [5049  line  21].  In  [5040  line  1],  we 
have  2Bj'2',  as  in  the  second  term  of  [5049  line  21].  The  terms,  in  [5040  line  9],  give 
those  in  [5049  line  22]. 

Seventeenth.    The  common  factor  of  the  terms  in  [5049  line  23]  is 

fm.—  .—  .y.  sin.fFW — v-\-mv). 
^        a^     a  ^^  ' 

The  terms  connected  with  this,  in  [5025],  is  ^;     and,  in  [5032],  is  :^  ;     whose  sum  is    3,     [5049j] 

as    in  [5049  line  23].     Lastly,   the  term  [5040  line  1],    depending  on     Bl"',     is  as  in 

[5049  line  23]. 

Eighteenth.     The  common  factor  of  the  terms  in  [5049  line  24]  is 

im  ■— . —.y.5\n.[s'v-\-v — mv). 

The  term  connected  with  this,  in  [5025],  is     g!  ;     and,  in  [5032],  is     — I;     whose  sum 
is     f,    as  in   [5049  line  24].     The  term  [5040  line  1],  depending  on     B^^^\     is  as  in  the     [5049«] 
last  term  of  [5049  line  24].     Hence  it  appears,  that  all  the  terms  of  the  equation  [5049] 
agree  with  the  preceding  developments. 

*  (2884)  The  quantities  B[°\  ^f,  in  the  factor  of  7.sin.(^«—a)  [5049 line  1-4], 
are  multiplied  by  1— fe'^,  and  some  of  the  other  terms  of  that  factor  are  multiplied  by 
c'2  ;  so  that  we  may  put  the  whole  factor  under  the  form  p"-\-  q".  e'"  [5053].  Moreover,  as 
the  equation  [5049]  is  linear,  we  may  notice  the  terms  depending  on  sin.(^?; — è)  separately; 
and,  by  restricting  the  value  of    «     to  this  term,  we  shall  have,  from  [5049, 5053], 

^  =  S  +  '  +  ^V"+'i"-  <=")-y-  sin.fei'-^).  [50516] 

Substituting  in  this,  the  value     s  =  '/.sin.(^f — è),     and  its  second  differential, 

dd3  ddy     .  .\    ,  n^y  f  ^^\  /  ,x         <W^  f  ,s  (       'i^\^     ■      f 

d^-  =  J^-^'^-(S^-^)+^%\S-J,)-^os.{gv-ê)-Y.^.cos.(gv-6)-^.  [g--j  .sm.{gv-6);    ,[5051c] 
VOL.  III.  127 


[505:a] 


506  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

ddù         r.     '^y     f  ^^ 

[5051]  '^^'^■■Â^-^-I.Xê-J. 

[5052]  -  ^^'^  ^^  ^^^^ 


0=       ■d^^-''\[^-dv)-^\+'<P+^''^-'-^ 


[5053]     p"-Ji-q".e'^     denoting  the   coefficient  of    -y.s'in.Cgv  —  6)  in   the  differential 

/''  9"-     equation  [5049]  ;  in  which  we  must  observe,  that    B['^^  and    Af^     contain 

1^°^^]     inplicitly  the  factor     (1— |e'^)     [4976a, 6].     The  first  of  these  equations 
gives,  by  integration,* 

[5055]  d^  —  -"-7  1 

//    being  an  arbitrary  constant  quantity.     The  equation   [5052]    gives,  by 
neglecting    — -j,     and  the  square  of    q".e'%-f 


[5056] 


do  io".e'= 


considering     v,     y,     é,     as  variable  quantities,  we  get, 

1505«,    0=-!^St-..^:.(^;)^.cos.(g.-,)  +  ^'^,-.4(^-2f-l]-Hy'«".>^,infe.-.,. 

This  equation  is  satisfied  by  putting  the  coefficients  of  cos.(^w — è),   sin.(^y — è)  separately 
equal  to  nothing  ;    by  which  means  we  obtain  the   equations   [5051,  5052],  respectively. 
'■  The  whole  calculation  being  similar  to  that  for  the  motion  of  the  perigee,  in  note  2852 

[4973rt— A]. 


*  (2885)     The  equations  [5051,5052]  are  similar  to     [4973,4974],  and  are  solved  in 

dv 


dé 
the  same  manner  as  in  [4977a,  Sic.].     Putting,  in  this  case,     g —     — W^,     we  get,  for 


[5055a]  _  jji)        jjfT 

its  diflerential,     — JT  =  "T^-     Substituting  these  in  [5051],  we  obtain, 

.  dW,       _„.   dv  dJV        ^    dy 

[50556]  ^  =  -^-rf^-2^^'-^5     or,     --^  =  2.-; 

whose  integral  is     ^  =  H-V^  ;      H    being  the   arbitrary  constant  quantity.     This   is  the 
same  as  [5055],  and  is  similar  to  [4977  or  4977c]. 

t  (2886)     In  like  manner  as  we  have  neglected     ddE,     or     dde,     in  [4973e — h],  we 
may  neglect     ddy,  in  [5052]  ;  and  then,  dividing  by     y,     we  get. 


[5058] 


VII.  i.  «5- 14.]  INTEGRATION  OF  THE  EQUATION  IN  s.  507 

therefore,  if  we  consider    p",     q",     as  constant,  which  may  here  be  done     [5056] 
without  any  sensible  error  [4979a,  &c.],  we  shall  have, 

ê  =gV—^ï+^".V—  y^.fe'\dv+>.  ;  [5057] 

>■    being  an  arbitrary  quantity.     This  gives,  [5057'] 

s\n.(gv—è)  =  sin.  I  ^/rf^".v+  ^^^^  Je'"~.dv  -^  |  . 

Hence  it  folloivs,  in  conformity  ivith  observation,  that  the  nodes  of  the  moon'' s 

orbit  have  a  retrograde  motion  upon  the  apparent  ecliptic,  which  is  represented 

by,* 

i„" 

Retrograde  motion  of  the  nodes  =  {^i-j-^" — l}.v+    /^j^,  -fe'^.dv. 

Motion  of 

This  motion  is  not  uniform  by  reason  of  the  variableness  of    e';     and  the  «he  nodes 

secular  equation  of  the  longitude  of  the  node  is  to  the  secular  equation  of  the 

It 
perigee  as       ,-^— ^,     is  to     —  /  ■        .f  [5060] 


or,  by  reduction, 

S-'i  =v/(l+i'"+?".e'-^)  =v/(l+i>")+|rg-)+^-  [5056a] 

Neglecting  the  square  of    q".e'^     [5055'],  and  reducing,  we  obtain  [-5056].     Multiplying 
this  by     dv,     and  integrating,  we  get  [5057]  ;  or,  as  it  may  be  written, 


[5059] 


g„-é=[^{l+p").v+-^^.fe'^dv-xy. 


[50566] 
and,  by  taking  the  sine  of  both  members,  it  becomes  as  in  [5058]. 

*  (2887)     In  [4818or505lJ]   the  quantity    gv—6     represents    the   moon's  distance 
from  the  node,  which  is  equal  to 

{^i^+P"U-+^^l^yfe'^-^v->.]    [5056i].  ^,^^,^^ 

Subtracting  from  this  the  moon's  longitude  v,  we  get  the  expression  of  the  retrograde 
motion  of  the  nodes  [5059]  ;  observing,  that  by  taking  the  integral  fe'^.dv  from  d=0.. 
where  the  motion  of  the  node  is  commenced,  we  may  neglect  the  quantity  >.. 

t  (2888)     The  term  of  the  expression  of  the  motion  of  the  moon's  perigee,  upon  which 
its  secular  motion  depends, is  represented  in  [4982]  by  lq'.fe^.dv=^—T^..fe'^.dv    [4979].    [5060a] 


508  THEORY  OF  THE  MOON  ;  [Méc.  CéJ. 

The  tangent  y     of  the  inclination  of  the  moon's  longitude  to  the  apparent 
ecliptic  [4813],  is  also  variable,  since  it  is  represented  by,*' 

[5061]  y=   ^H.(g-^£iy'     [5055]. 

The  seca- 

IVonofT    But  it  is  evident,  that  its  variation  is  insensible  ;  and  this  is  the  reason  why 
bie'"'^""     the  most  ancient  observations  do  not  indicate  any  change  in  the  inclination, 
although  the  position  of  the  ecliptic  has  varied  sensibly,  during  that  interval. 

We  shall  then  have  the  following  equations  ;t 


The  similar  term  in  the  motion  of  the  node  is ,    .fe'^.dv  [5059];  the  negative  sign 

being  prefixed,  because  the  motion  is  retrograde.      This  last  expression  is  to  the  former  in 
the  ratio  mentioned  in  [5060]. 

*  (2S89)     We  may  observe,  that  the  equations  [5051 — 5059]  are  similar  to  those  in 
[4973 — 4982],  and  maybe  derived  from  them.     Thus,  by  changing     c,     to,     — p,     — y^ 

^  ,    into     ^,     ê,     p",     g",     7,     respectively,  we    find,  that  the  equations    [4973] 

a  *" 

and  [4974]  change  into   [5051, 5052],  neglecting     ddy  ;     [4977]   becomes  like    [5055]; 

[5061i]     j-^g^gj  j.j.g    |-5Q5g-].    [4980]  like  [5057];    [4981]   like  [5058],  changing  cos.  into  sin.; 

lastly,  [4982]  like  [5059].      Hence  it  is  evident,  that    we  may  apply  the  same   method, 

to  prove,  that  the  secular  inequality  of    y     is  insensible,  that  we  have    used  for     c,     or 

'^■1,     in  [4987,  Sic]  ;    observing,  that  both  these  inequalities  depend  on  terms  of  a 

similar  form  and  order. 


I 


[5061a] 


[5061c]  ^ 


[50626] 


t  (2890)     If  we  suppose  any  term  of    Ss     [4897]  to  be  represented  by  i?.<;^u.(ii)  +  s), 
[5062a]    it  will  produce,  in     Ti+«)     the  term      |l — i^\.B  .&iA^.  (iv -\-s).       Substituting    this    in 

[5049],  and  putting  the  coeflicient  of  each  sine  equal  to  nothing,  we  shall  obtain  the 
equations  [5062 — 5077]  ;  taking  them  in  the  same  order  as  they  occur  in  [5049]  ; 
and  reducing  them,  by  dividing  the  equations  by  the  factors  depending  on  e,  e',  y, 
without  the  braces.  No  other  reduction  is  necessary  in  any  of  the  terms,  except  in  that  in 
[5049  line  18]  ;  in  which  we  must  substitute 

[2—2m—gy—l  =  (3  —  2m  —  g).{l  —  2m—g)  ; 
by  which  means  we  have, 

1'^  +  ~%{2c-2+2m)        ~        ^^  ^'•i^^   2.(2c-2+2m)    S 

—        W      ~"i     '=^-2.{2c-2+2m) 


VIL  i.  ^  14.]  INTEGRATION  OF  THE  EQUATION  IN  s.  509 


o=! 


0= 


0=^ 


0=1 


0= 
0= 
0= 


0=1 


0=1 
0=1 


0=1 


0=1 

o={ 

0=1 

0=1 


[5062] 


2  a    C(l+§-)-{l+2eW-(2+w»).'/— |e"h 
—(2—2m—gy\.B['^—^m.~.)     ,.      ..  C. 

«,    i  +  ^-^=^^— 4J<»'+104".e^— 25f'   C' 

V,  1 — w  "  '  ^       J 

_(2_2m+^)-^i.5<"+  |m!^.  Si.(l-o-)+5y'  i;  [5063] 

—(g+cy-\.Bf+im~.  -.\Bf^—2+(\—m).(3—2m—g).B[''^;  [5064] 

—(g—cy  I  .^f  +  4 wi . -  . l^f  — 2— 24"+(l+m).(3— 2»i— ^). 5f '} ;         [5065] 

_(2— 2»i— o-  +c)-] .B;^'+  f  Jrt'.  - .  I  (l+«-).(l— m)— 25f '+5^  i 5  [5066] 

a, 

—(2—2m+g—cy\.Bf+iîïï.  -  -K^— l).(l+m)+5f— 24"};  [5067] 

_(2  _2m-o--c)^  I  .Bf  +!«'■-  -Kl  +^).  (1  +»î)+5f  +2Af-2BT  \  ;         [5068] 

^/ 

— (o-+m)2 }  .B^P+lL-.  1 3+25f '+J-(3-2m-^).5f  )-(3-3m-^).5î'°' }  ;  [5069] 

_  {g—mf] .  fif +f  î^.-.  1 3+25f' — |(3-2m-^).5f -(3-»i-^).  5f' }  ;  [5070] 

_(2_m— ^)^^5f'+p.^{Kl+S•)+2Si'"+3■Bl°Ml+^-'»)-Si''};  [5071] 

_(2— 3;«— ofi  .iBi'O'+fm'AlSBi'»'- J(l+o-)+35p-(I+^+m).B7'l  ;  [5072] 


'2B<'»— 5— 10^«4-4^1i"— (3— 2m— 2c+g).B','=^ 


—(2c—gY\.B'~''^-{-lm.-.l  nn-Lio™  I  a    "x  >;     [5073] 

(^     V.  6/  v6-r  y      2.(2c-24-2»«)         '  ^ 

_(2— 2m— 2c+^)^|.5i'^'+âm.-.^  J;  [5074] 

"'  ( +I04'>— 4.4V"— 25o""  > 

—(2c+g—2-{-2mf\.B['^^Jrlm.-.{  f;  [5075] 

"'  ( +10^"— 4.4/"'— 52?r>      ) 

_(g+m_l)2^.5^"')+3 ,7'."  .  ^  3+2^(»'  \  ;  [5076] 


_(^+l_^)2|.5(.5)+.^.^.  s  1+2 ^<'^'  I  .  [5077] 


0= 

VOL.  III.  128 


510  THEORY  OF  THE  MOON;  [Méc.  Cél. 

16.     It  now  remains  to  determine  the  value  of    t,     in  terms  of    v.       For 
this  purpose,  we  shall  resume  the  equation  [4753], 

dv 

[5078]  dt= „.  ,^  =::  . 

We  must  substitute  in  it  the  value  of    u     [4997]  :  namely, 

]     (  l  +  c2+i7^+f3+e.(l+e=).cos.(a'— t.)^ 
[5079]  M  =  - .  <  >  +*«  . 

"    (    -i7'.(l+e^-i7').cos.(2gv-2ù)      S 

âv 
We  shall  have,  in  the  first  place,  by  developing  the  factor       —  ,       a     term 

independent  of  the  cosines,  which,  by  the  nature  of  the  elliptical  motion, 

2      7 

[5080]      must  be  equal  to*  — Jr—  [5081o,j:;]. 


*  (2891)     If  we  put,  for  brevity, 


[5081a]  ^  <  1    ,   2       /■  /'''Q\     '^''■'  )  4 


dv 
[5081a']     the  expression  [5078]  will  become,     dt=~.Q^.       The    development    of      Q',     in   a 


[50816] 


series,  gives,  O'— i_l     f  f'!S:\     ^    1   _L     {r'^S    *\2     fcp  . 


which  is  of  the  same  form  as  the  factor  of  [5081],  depending  on  Q.  The  terms  of  u 
[5079],  independent  of  Su,  have  been  heretofore  denoted  by  u  [4826,  4861,  8ic.;  4997]  ; 
and,  by  retaining  this  vahie,  the  second  member  of  [5079]  will  be  u-\-&u.  Substituting 
this  complete  value  of    u     in     cit     [5081n']  it  becomes, 

dv.q  dv.q      /     ^èu\-2      Cl         2fa    ,    3fc9       ,      >     ,    ^, 

[508id]         ''^=T^H^=Tii^- •(,!+, 7;  =\ï^-ï7s  +  ^^;^-^''■l■^'■^ 

[5081e]  =l,i-2(«^»)-^i^  +  3(«^«)^-^a.-  ^-  1  •''-^' 

observing,  that  we  must  substitute  in  [508 le],  for     u,     all  the  terms  of  the  second  member 
of  [5079],  excepting     &u.     Now,  by  neglecting  terms  of  the  fourth  order,  we  have, 

[5081/]  î=i^.(l+Je3+è7,^)     [4866/];     whence,     I  =  ±-^.{1+^,^+1  f). 

Multiplying  this  by     m"^     [4866^],  we  get, 
[5081g]     _L_— "J^.|(i_f_Je2_^y2\_3g_Q_i^2).cos.Cî)+3e'-^.cos.2cî)+f7^cos.2^i;-|cj'2_cos(o^^,_^j,)|. 


VII.i.§15.]  DIFFERENTIAL  EQUATION  IN  t.  611 

Then  we  shall  have, 

1 — 2e.(l — {y^).cos.{cv—-a) 


-)- 3g2_  (  1  _|.^e2— J/2)  .cos.(2cu— 2ra) 


3     r     /dQ\  rf-w-12 


iioû  in  I. 


[5081] 


(U=^-(  \  -1er  |cos(2^i)-cy-2t)4-w)+cos(%y+c«-2()-5i)}  )\  —  hc. 

(  l+àe2-^72— 3e.cos.(cu— a)+3c2.cos.(2c»— 2ra)  p   C,_L    /•/'f^\    ^ 
-2ai«  J  > .  <         A2  -y  ^  d„  j  •  „2 

(  -H>^-cos-(2gi»— 24)-ie>2xos.(2gy-c»-2e+TS))    (  +  &c. 

+3.(a  5u)-2. 1 1— 4e.cos.(cu— ra)  j .  { 1— &ic.  \ 


Substituting  this  and  Q'  [5081J],  in  the  terra  of  [5081e]  depending  on  the  first  power  of 
aôu,  we  get  the  corresponding  terms  of  [5081  lines5,6]  ;  neglecting  the  very  small  term  of 
the  fifth  order,  depending  on     ey^.  cos.cv.     Again,  we  have  in  [48706], 

M~^=  a'*.\l — 4e.cos.cu-|-^c.  j.  fSOSlfcl 

Multiplying    this   by     —  =:     ^         nearly   [5081/],  we  get, 

1 


=  -7.|l — 4e.co3.c«+&z,c.|.  [5081«] 


hui.  a2  a 

Substituting  this  and  the  value  of  (^  [50816],  in  the  term  [5081e]  depending  on  («iÎm)^, 
we  get  the  corresponding  terms  of  [5081  line 7].  We  may  observe,  that  aSu  [4904]  is 
of  the  second  order  ;  so  that,  in  these  terms  of  [5081  lines  5 — 7],  we  have  explicitly 
retained  terms  as  far  as   the  fourth  order  inclusively.     The    only  remaining  term  of    di 

[5081e]  is  the  first,         "  ^    ;     and  the  quantity   Q'  is  represented  by  the  terms  depending 

on     Q,     in  [5081  lines  1 — 4].     The  factor  connected  with      Q',     is  of  the  same  form  as 

dv 
''kvfi 


[50814] 


[508K] 


the  value  of    dt,     in  the  first  of  the  equations  [531];  namely,     dt  =~;     from  which    [5081m] 


the  elliptical  value  [534c,  535]   is  deduced.      This  has  the  constant   factor     a^.      If  we 

compare  this  factor,  or     — ,     with  the  calculation  in  [5346,  &c.],  we  shall  easily  perceive, 

that  the  numerator     a^,     is  introduced  by  the  term     u^     [508b«],  which  is  not  altered  in 

the  disturbed  orbit  [4861]  ;  but  the  denominator  \/n,  which  is  deduced  from  h  [5346,&ic.],     [SOSln] 

is  changed  into    \/«,i    in  the  disturbed  orbit  [4863]  ;  and,  by  this  means,  it  becomes    . 

/i,       [5081o] 

If  we  take  the  differential  of  [4828],  and  divide  it  by  n==ar^  [4827],  it  becomes,  by  using 

the  abridged  notation  [4821/], 


•512  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5081']     That  part  of  the  second  member  of  this  equation,  which  is  not  periodical,  is 


„a         (  1  —  2e.(l — l-)'^).cos.cv-\-^^.cos.2cv — e^.cos.3cv-\-iy^.cos.2gv  'i 
[508ip]  dt=--.dv.<  >• 

V"-        (    —iev^.cos.{2gv—cv)  —  iey^.cos.{2gv-\-cv)  } 

Now,  changing  the   term     —     into     —     [5081o],  we  ought  to  get  the  factor  which  is 

independent  of     Q,     in    [5081  Unes  1 — 4]  ;    and,  upon  examination,  we  shall   find   they 
[5081g]     agree  ;  except  in  some  terms  of  the  fourth  order,  connected  with  cos.Scw,     cos.S^î),  which 

were  neglected  in  computing  the  function  [5081p  or  4828].      To  prove  this,  we  shall  repeat 

the  calculation  [4821/i — m]  ;  retaining  only  the  terms  which  produce  quantities  of  the  fourth 
'        ''J     order  in     e,     7,     and  are  connected  with  the  angles     2cv,     2gv.     By  this  means,  [4821i] 

becomes  as  in  [5081?<]  ;  observing,  that  the  last  term  arises  from  -|-5(/+e-cos.ct')'',   which 
[5081s]     is  omitted  in  [4821i).     Now,  from    f:^ly^—i7^.cos.2gv    [4821c],  we  obtain,  by  noticing 

only  the  angle     2gv, 

f=—^y^.cos.2gv;  f2  =  —  l7\cos.2gv  . 

[508U]  The  first  of  these  expressions  ought  to  be  changed  into  /= — (r^y® — j^v^)-cos.2^r,  in 
order  to  notice  the  term  of  the  fourth  order,  which  was  neglected  in  [4812a,  6].  Finally, 
the  term  —4  [Sfe^.cos.'^cv)    gives,  by  noticing  only  the  terms  depending  on  cos.2^i),  cos.Scd, 

_6/e2_6/e2.  cos.  2c«  =  fe2i.^cos.2^'-«— 3eV.cos.2cy     [5081s]. 
Hence   [5081m]   becomes  as  in  [5081«]  ;    and,  by  substituting     cos.^t^  |cos.2cy-]-&ic.  ; 
cos.''<;«  =  icos.2cv-\-k.c.     [6, 8]  Int.,  we  obtain  [5081  w]  ; 

[5081u]  dt^P.{l+2y^).dv.l—2f-Jr3{c^-.cos.^cv-\-P)—4.Qife^cos.^cv)  +5{e\cos.''cv)  \ 

„,     ,      iSfiv^ il=-/).COS.22-«+3(e'3.COS.^CT iy*.C0S.2!rv) 

[5081»]  =hm-^2y^).dv.]    ^'"^       l\{         ^    ^3^3  ^l,         f    [ 

(  -|-Je^y  .cos.2o-« — 2^-'y^.cos.2cv-f-oe^.cos.cv) 

[5081«,]  =P.{l-\-2y^).dv.\{ie^-^t^y^+^e%cos.2cv+(iy^+ie^y^—iy').cos.2gvl. 

The  terms  between  the  braces  are  of  the  second  and  higher  orders  ;  therefore,  in  finding 
the  terms  of  this  function,  of  the  fourtli  order,  we  must  obtain  the  factor  h^.{l-\-2y^) 
correctly,  in  terms  of  the  second  order.  This  value  is  easily  found  from  [4823]  ;  which  gives, 

[5081X]  f''-  (1  +2"/^)  =  «^-  a-l^'+hy')- 

If  the  factor  I — ^e^-{-^y^  be  connected  with  the  two  terms  of  the  second  order  in 
rSOSlw],  it  will  produce  some  terms  of  the  fourth  order  ;  and,  by  retaining  terms  of 
this  order  only,  we  obtain  the  expression  [5081y],  which  is  easily  reduced  to  the  form 
[5081z]  ; 


VII.  i.  >5, 15.]  DIFFERENTIAL  EQUATION  IN  t.  613 

represented  by,*  [508l"J 


r       $*e2(— |e2+iy2)— |eV+|e*^cos.2ct>) 
dt=a^.dv.{  }  t5081y] 

(  +||y=.(— fe2-fiy=)+feV-4y'Kcos.25-i;  ) 

=  a^.ch.  J  (J-e"— feV).cos.2ci)+(feV-èv*)-cos.2o-y^.  [5081i] 

The  terms  between  the  braces  in  this  expression  are  tlie  same  as  the  terms  of  the  fourth 
order  in  [50811ines  2, 3].  Hence  it  is  evident,  that  the  development  [5081]  is  correctly 
made. 

*  (2892)     The  function    ri-fCi)-  ~,      wliose    powers    and    multiples    occur  in     rgQgg. 

[5081],  has  already  been  developed  in  [4881',  4885,4889,  Sic],  and  in  the  variations  of 

these  quantities  [4930,  Sic.].      If  we   put  the  function   [4885]    equal   to     M^;     and  the    [50824] 

function  [4889]  equal  to     J\l^,     the  indices   denoting  the  order  of  the  functions;  we  shall    rrnpo.q 

neglecting  terms  of  the  sixth  order  ;  hence,     Q'    [5081&]  becomes, 

We  must  add  to  this  value  of  Q'  the  terms  arising  from  the  variations  of  the  function 
— ^M.,  ;  the  variations  of  the  other  terms  being  so  small,  that  they  may  be  neglected. 
The  chief  term  of  the  value  of    — iM„    is  that  which  is  noticed  in  [4929,  4930]  ;  namely, 


/     Q,3„4       •sm.(2.-2.'); 


2  h^.  u* 
whose  variation,  relative  to  the  characteristic  5,  is  evidently  represented  by, 

Su'  being  neglected  [5040«].  The  function  in  the  first  memberof  [4931m],  is  developed  in 
[4931_p],  and  we  shall  put  this  last  expression  equal  to  JV^,  and  that  in  [4932a]  equal  to 
JV^;  then  we  shall  evidently  have,  for  the  two  terms  of  the  variation  [50i?ls],  the  following 
expression 


[5082rf] 

[5082e] 
[5082/] 
[5082^] 


The   second   variation  of  the  same  function     — i-M^,      is   easily  deduced   from   that  of 

Jltu      [4942],   by  dividing    it  by     — 2?<  =  — 2(r^,      nearly     [4826];     using   also    [5082A] 

VOL.  in.  129 


514  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

'-->  ^-  \  >+âî|ë^  +  !^;+i-  Mr)-+(4'U)']  I  [6092»]. 


[5082fe']    !!L^-=  „j2     [5094]  ;  whence  we  get, 


j-gQgg..,  ISm^       {A[^^fe^.cos.{2cv—2v+2mv) 

The  other  terms  of    — ~.f  (~  ]  •  -3,     which  are  noticed  in  [4944,  4945],  produce  the 

following  terms,  which  may  be  deduced  from  [4945  line  2],  by  dividing  by     — 2a~\     as 
in  [5082A]  ; 

[5082A] 


—  -^^  .  -',.faSii.dv.\3.sïn.(v—v')-^l5.sm.{3v—3v')\. 

The  terms  resulting  from  this  expression  may  be  obtained  in  the  same  manner  as 
[4946/]  is  deduced  from  [4945  line  2]  ;  or,  more  simply,  by  dividing  [4946/]  by  — 2a~' 
[5082A].     By  this  means  it  becomes,  by  using  the  value  of    m^    [50S2h'], 

15  m^       a       .,.,  cos.(t) — mv) 

[5082^]  -——  .  -  .  Ai'K \ 

4a'  I — m 


Now,  adding  together  the  functions  [5082c,  g-,  i,  1],  we  obtain 
^ ~         h^'-^   \dv  J  '  xfi    I"  2/1-1    •  V^ 


^^^■S)-^- 


1 5082m] 

15m2       (^p)2es.cos.  {2cB—2v~\-2mv) 

4~  ■  2c— 2+2/» 

15?ft-      a       ..Q     cos.('y — mv) 
A  a'       -  I— m 

Substituting     m^     [5082A'],  in  the  value  of    iVl    [4885,  5082e],  and  neglecting  terms  of 
[5082m']    {|-|g  second  order,  between  the  braces,  which  produce  only  terms  of  the  sixth  order  in    M^, 
it  becomes  of  the  form, 

[5082n]  J|//^-=3^2   5_L_.cos.(2t)— 2mi-)  +2P,.cos.(2y— 2m«+F)?; 

as   is   evident,  by  mere    inspection  ;    the    symbol     P^    being   the  coefficient  of  the    first 
order  of  any  term  between  the  braces  in  [4885],  and     2v — 2mv-\-V    the  corresponding 


VII.  i.  «5. 15.]  DIFFERENTIAL  EQUATION  IN  t.  516 

The    coefficient   of     dv,     in    this    function,    is    not    rigorously    constant.     [5082'] 

angle.  The  square  of  this  gives,  by  neglecting  P^,  and  the  angles  Av  —  Amv , 
Av — imv-\-V, 

21  m^  CI  ,        „  ^^}  [50820] 

Now,  it  is  evident,  by  inspection,  that  the  terms  between  the  braces  in  this  last 
expression,  are  easily  derived  from  those  between  the  braces  in  [4885],  by  rejecting 
2î)  — 2m«  from  all  the  angles,  and  taking  half  of  the  first  term  in  [4885  line  I]  ; 
hence  we  get, 

1  /  2  (1+m)      ,     2  n  —  m)  \ 

I       ^    1      ^    _j V i_).e.cos.cw 


„   _         27  m"  j   4(1— to)         V2— 2m  — c        2— 2m  +  c 

^^2'   =^    16(1  — m)-   )  /       7  1     \  (  ■     [50^*^?] 

/  +  ( I  .  i  e'.cos.  c'mv 

I.  ^\2  —  3m         2  —  mJ 

Substituting  this  in  [5082m],   and  for    M^,     M^,     JV^,     JV, ,     writing  the  functions  to 
which  they  correspond  [50826,  6',/],  we  obtain. 


'?='-r.-/(f)-S+«-[/(S)v:]-«'«- 


=1— i.function  [4885]  —  i.function  [4889]  —  ia.function  [4931^]— |a.function  [4932a]  2 

/        1  /2(l+m)  2  (!_,«)  \ 

i '      '    .  ^ i_  I    e  cos  cv 

21m*  \4(1_m)         V,2— 2to  — c        2-2m  +  c/' 

+Î6Tl"=^)  •  )  f       1  M    >  '  '  C  3 

(  +V2=3^-2^n)-i'-''''-'"''' 


Ibjrfi     {A[''>)^e^.cos.  i2cv  —  2v-\-2mv) 


[.5082?] 
4 


4  2  c— 2+2m 

15 m2      a      ...    cos.(f — mv) 
4         o       ^  1  — m  ^ 

The  expression  is  now  reduced  to  so  simple  a  form,  that  we  can;  by  the  mere  addition  of  the 
terras,  obtain  the  complete  value  of  Q',  as  in  the  following  table  ;  rejecting  such  terms 
and  angles  as  have  beenusual'y  omitted  ;  and  putting 

_"  a 

TO  .  -  =  m-,     as  in  [5082/t']  ; 


616  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5082"]      yjQ   I^.^yg  sgg„^  jj^  [4968],  that  the  expression   of      i     contains  the  term 


Expres- 
sion of 


Terms  of  [5082fy]. 

[5082^  lines  2,  3] 
[4885  line  1] 
[4885  line  2] 
[4885  line  3] 
[4885  line  4] 
[4885  line  5] 
[4885  line  6] 
[4885  line  7] 


Corresponding  terms  of  Q=l_L./^Î^YlV-/r^-tT-&c. 


[4885  line  8] 

[4885  line  10] 
[5082«]      [4931pline24] 
[5082çline4] 
[4885  line  12] 
[4931pline26] 

[4885  line  13] 

[4885  line  14] 

[4885  line  15] 
[493  Ip  line  29] 
[4889  line  1] 
[4931^  line  31] 
[4932«  line  3] 
[50829  line  5] 
[4831ijlines39, 13] 
[4831^  lines  14,17,20] 

[5082<7line3] 

[4931iJlines7,16] 
[4931_pline6] 


27  m4 

"*"  64    ■  [\-mf 

(l+2e2-|e'2)  _        ^      , 

—  -^-^--^.cos.{2v—2mv) 


[Tliis  line  has  no  factor.] 


2(l+m) 
'2-2711— c 


(l+fe^— i7^— Je'-).e.cos.(2y— 2OTÎJ— cr) 


2(1 -m) 

.cos.(2t) — 2mv — c'mv) 


2(2— 3m) 


+ 


2(2- m 

7  (2+3m).ec' 


2  (2_3,„_c) 
7  (2-3;n).ec' 


2  (2— 3ot+c) 
(2-|-m).ce' 


cos.(2v — 2mv-\-cmv) 

cos.(2u — 2mv — cv — c'mv) 
.COS.  (2y — 2mv-\-cv — c'mv) 
COS.  (2t) — 2mv — cv-^c'mv) 


All  the  terms 
except  the 
first  line  have 
the  conuiion 

factor    ^m'. 


2{2—m—c) 
ri(10+19m+8m2)^ 
+  )-2Ar  >  .^~^.cos.i2cv-2v+2mv) 

-4-  \  f'o o  I  o    •cos.(2gi; — 2v-\-2inv) 


(2— m).v2 


4(2o--f-2-2m)' 
17e'2 


.cos.(2gv-\-2v — 2mv) 


.COS.  (2« — 2mv  —  2c'mv) 


+ 


+  ■ 


Cy^ 


.cos.(2v — 2mv — 2gv-]-cv) 


+ 


2(2— 4m) 

U(5+'«) 

\  +2^o'i'''  S    2-2OT-2â-+c 

-]-2^i'^'  (    1      cos.(î> — mv) 

+  2?«.^fi  f^'a' 

....neglected  ' 

-  SAP  +20.5i"e2  -2.^^31  - 
J^2Ai'^^bAfe^—bS1h''  {    £_' 


1 — m 


.  COS.  e  mi' 


9     m3_   C  _7 ^ 

+161— m'  (2 -3  m      2^ 

+  \  lA^^^-^2Af } .  ~XQS.{cv—c'mv) 

-\-2A[^'>e.cos.cv. 


1 
2 

3 
4 
5 
6 

7 
8 


10 
11 
12 
13 
14 

15 

16 

17 
18 
19 
20 
21 
22 
23 

24 

25 
26 
27 


VII.  i.  ^15.]  DIFFERENTIAL  EQUATION  IN  t.  Ô17 


Q—        '2  - 

—  — — ;     which  gives,  in     o",     the  term*     ^Wiaf.e'-:     thus,  the  quantity      [5083] 
— —    contains  the  term     |«/.  <?«.?«  .e'-     [5083(?]  ;     now  we  have  nearly,      [5084] 

«/=-,  m  =  m-        [5092', 5093]  ;  [5085] 

Q       2 

therefore,  the  expression  of  the  time     t     contains  the  term     — — .fe'~.dv;      [50861 
consequently,  the  value  of  the  moon's  true  longitude,  in  terms  of  the  mean 


We  have  omitted,  in  tlie  preceding  table,  several  terms  on  account  of  their  smallness. 
Tims,  we  iiave  neglected,  in  line  7,  tlie  terms  depending  on  Af^  [493 Inline 22]  ;  in  line 
9,  the  terms  depending  on  ./5/9'  [1931^7 line 23]  ;  inline  20,  the  terms  depending  on 
•^o^\  \  [4931/J lines 35,  37]  ;  in  line  27,  several  terms  of  [4931p,  5082y],  of  the  fifth 
and  sixth  orders.     Besides   these,  there  are  others  depending  on  the  angles 

2v — 2mv-\-cv-{-c'mv,     2cv-^2v — 2mv,     v — mv±c'mv,     2gv — cv,     cv-^-dmv,     2cv. 
These  are  neglected,  because  the  terms  arc  of  the  fifth  or  sixth  order,  or  are  connected  with 
angles  which  do  not  increase  the  coefficients  by  integration  in  finding    t,    from    (It    [5081]. 
In  the  terms  depending  on     cos.(y — mv),   we  have  retained  the  terms  dependin'^  on    ^  '"' 
[5082sline  21],  and  neglected  a  term  of  the  same  order,  depending  on  A^"'>  [50S2sline  22].     [5082»] 
This  is  done,  because  ^-j''^  is  required  to  a  great  degree  of  accuracy  in  [4874, 4904  hue  18]. 
The  function      Q'     [5082s]  is  to  be  subnituterl   in   [5031],  and  then  we  may  obtain  the      [5082t>] 
constant  terms  [5082],  as  we  shall  see  in  note  2898  [5093m].] 


a^=a;'.(l  +  im~.e'^+hc.y,     hence,     ~=a,^.dv.fl  +  §m'.  c'^+ &icX 
VOL.  III.  130 


[5082<] 


*  (2893)     If  we  put,  for  a  moment,    —    to  represent  the  terms  of  the  second  member 
of  [4968],  exclusive  of  the  first  and  third,  we  shall  have, 

-=-.(l-~.e'^+m\  [SOSSa] 

a        a,     \  4  '/ 

The    quantity     m,    contains  another  term,  depending  on     e's,     of  the  order       in.JÏ?  c'^, 

2 

which  may  be  neglected,  in  comparison  with  the  retained  term ^  e'^  [5083a].  Involving     rrngoi,-] 

[5083a]  to  the  power    — 2,     we  get, 


[5083c] 


518  THEORY  OF  THE  MOON  ;  [Mtc.  Cél. 

[5087]      longitude,  contains  the  term     — ^mr.fe'^.dv,     or     — %m".  fe'-.ndt.      Hence 

Kalin  or  _        °  "  .  -  . 

liVmo-""    it  follows,  that  the  three  secular  equations  of  the  mean  longitude  of  the  moon, 
[,nS^     iis  perigee  and  its  nodes,  are  to  each  other  as  the  three  quantities* 

llie  longi- 
tude, pel  Î-  2  „ 

[5089]  sm,  ^-^,  -4=. 

It  is  true,t  that  the  terms,  depending  on  the  square  of  the  disturbing  force, 

This  expression  contains  the  term  ^af.dv.m.e'^,  as  in  [5084],  and  by  using  the  values 
'■  ■'     [5085],  it  is  reduced  to  the  form     —.e'^.dv,     which  evidently  represents  the  chief  term, 

depending  on  e'~,  in  the  value  of  dt  [5081];  and,  by  integration,  we  get,  in  t,  the 
[5083e]     term    —-.fe'^.do   [50S6].     Changing  its  sign,  and  multiplying  by  7i,  we  evidently  obtain 

g„ja 

the  corresponding  expression  in  the  moon's  apparent  longitude  v  [5095],  — -^.fe'^.du  ; 
[5083/ ]  'i 

which  becomes    — -—.fe'^-ndt  [5087],  by  substituting  the  mean  value  of  c/d  =  ?i(/<  [4828]. 

*  (2894)     The  secular  equation  of  the  moon's  longitude  is 

—  îm^.fe'Kdv     [5087]; 
[5089a]     that  of  the  perigee  is 


i.--^ — .ft'^.dv     [4982,4979] 


and,  that  of  the  nodes  is 


[5089il  —  1. — " .  /"e's  .  dv      [5060rt— 5061a]. 

Dividing  these  three  expressions  by  the  common  factor     — |  ./e'  -.  dv ,    we  find,  that  these 
three  secular  motions  are  to  each  other  as  the  quantities 

I   (2895)     We  shall,  in  this  note,  make  some  developments  of  the  functions  which  occur 
in  [5081],  preparatory  to  the  calculation  of  the  values  of     C'f,     C^J\  &c.  [5096 — 5116]. 


f  5090a.] 


We  shall  commence  with  the  computation  of  the  terms  of  the  Jirst  pari  of  dt,  or  that 
which  is  independent  of  a5u,  and  arises  from  the  product  of  the  two  factors  included  in 
[5081  lines  1 — 4].  These  are  found  in  the  following  table,  which  does  not  require  any 
particular  explanation  ; 


VII.  i.  §15.] 


DIFFERENTIAL  EQUATION  IN  t. 


519 


produce  a  little  alteration  in  the  secular  equation  of  the  mean  longitude  ;     [5089] 


Terms  of  the  first  factor  in]         Factor  Q' 
[5081],  between  the  braces.      [5081  or  5082«] 

whole  of  [508:2«] 


-2e.(l — ^y-).cos.cy 


e2.(|-j--|-e2_  jy2)  .cos.Scr 

.|e^.cos.2CT 

i-/(l+te2-i72)cos.%z> 

— e'.cos.Scu 
—  |c-/2.cos.(2g'B — cy) 
— £e?^.cos.(2o'f+ci') 


1 
[50S2«  line  2] 

[5082*  Ibe  3] 

[5082s  line  4] 

[5082*  line  5] 

[5082s  line  6] 

[5082s  line  10] 


Corresponding  terras  of  [5081]. 


whole  function  [5082s]  multiplied  by 


\/a, 

— 2c  (  1 — \y-).cos.cv 
.J!t  ,n_l_Oea_,^2_s,/2^   ^+cos(2v-2mv-cv)] 

.3^(1+^)  C-cos(2.-2m.) 

•2_2m_c'^^+^^    ^^    ^'    '^    l-cos(2i>-2»it,-2c«) 
3m2(l— m) 


2-3  m-^c 


c^.cos.(2t) — 2mi') 


3m2 

"4(l-m) 


cos(2t)-2mi') 


[5082s  line  2] 
1 
1 
1 


-\-î'>n^-  K — 7r--ee'.  cos.(2w — 2mv — cv — c'otd") 

'  J. —  Am  ^  ' 


-Tr —  .ce'.cos.(2î) — 2m« — cv-\-c'mv) 
2— m  ' 

3m2.(10+19m+8m3).e3 


8.(2c— 2+2m) 


.cos.(2« — Imv — cv) 


9niS 


e2.cos.(2ci; — 2t)4-2»nv)  \    \/a,  ' 


First  part 
of  the  ex- 

Q    pression 


16(1— m) 
+(  1  +ie^— Jv-)  •  J7--  COS.  2^u 

■f|S)  ■  (l+Je2-Jy2_5e/3)  .cos.(2^«-2«  +2mr) 

— e^.cos.Scj; 

— fe7-.cos.(2o-j; — cv) 

— ^ej^.  cos.(2^i'+cd). 


10 

11 

12 
13 

14 
15 
16 
I'l 


[50906] 


In  the  next  place,  we  shall  compute  tlie  second  part  of  the  value  of    dt,     depending  on 
aSu,     which  is   contained  in  [5081  lines  5, 6].       Now,     a  Su     is    of   the   second  order; 
therefore,  in  calculating   the  product  of  the  two  factors  by  which     aSu     is  multiplied,  we     [5090c] 
shall  not  want  any  terms  beyond  the  fourth  order,  and,  in  general,  it  will  suffice  to  compute 
them  to  the  second  or  third  order.      We  shall  find,  in  the  following  table,  the  product  of  the 


520  THEORY  OF  THE  MOON;  [Méc.  Cél. 

[5089"]     but,     it     is     evident,     that     the     terms     which     have    a    very     sensible 


[5090e] 


two  factors  of  — 2a5u  [5081  lines  5,  6]  ;  or,  in  other  words,  the  product  of  the  expression 
Q'     [5082s],  by  the  following  function,  contained  in  [5081  lines  5,  6]  ;  namely, 
[5090a;]  J  +jfc2_^2_3e.cos.ci'+3fi2.  cos.2cv-\-i7^.cos.2gv—§e7^.cos.{2gv—cv). 


Terras  of 
[5090rf]. 


il 


—3e.cos.CT 


Factor     Q'    [5082*]. 

1 
1 

3m2  (l+2e2-*e'2)        .^    ^ 

3m2  2(l+m)e       _     „ 

T-2:2;;r-7"°<2"-2'«^-^") 


3e'2.cos.2CT 


^y^.Q.os.2gv 


3ot2  2(1— m  )e 
2~'2-2m+c' 


cos(2y-2)ft!)+ct!) 


1 


3'»2  1  /^  ^  N 


3m2 


2     2(1— ;n) 


,cosf2u— 2?«i)) 


Corresponding  terms  of    Q',     multiplied  by 
the  factor  {5Q<-Md\. 


whole  function  [5032s] 


— 3c.cos.CT 

L-^l-  f  l_LOe2_ie'9V    \  +cos(2«-2m«-cv)  > 
^8(l-m)-^'  '  ^'     .e   ;e.  ^  4-oos(2r-2my+™)  5 

9»t2.(l-|-m)      ^     C  _cos.(2u— 2mD)  ) 

2(2— 2m— c)'  *^'  ■  (  — cos.(2u— 2mv-2ct))  \ 

~2(2-2m+c)  ■  '^    •  I  — cos.(2y— 2mt)+2ciO  \ 


+3e2.cos.2cî) 

9m2.         g    c  — cos.(2v— 2ffiii-t-2ct))  •) 
"^8(1—7»)  ■  ^  ■  (  — cos.(2«— 2niy— 2ci')  \ 


-[-|y2.cos.2g-D 
9m2 


32(1— m) 


C  —cos. (2^1) — 2'i)-|-2nir))  ") 
■  I  — cos.(3g-iJ-[-2y— 2mi))  ^ 


1 
2 
3 

4 

5 

6 

7 


10 
11 


12 
13 


[5090/] 


a'^.dv 
This  function  [-50906]  is  to  be  multiplied  by    — 2a(5M.— — ,     to  obtain    the  second  part 

of  dt,  contained  in  [5081  lines  5,6].  This  process  is  performed  in  the  following  table 
[5090^].  In  the  first  column  are  given  the  terms  of  — 2  a  5m  [4904]  ;  in  the  second,  the 
terras  of  [5090e],  which  includes,  in  its  first  line,  the  function  [5082s]  ;  these  terms  are 
taken  in  the  same  order  in  which  they  first  occur  in  [5082s],  and  then  in 
[5090e  lines  2— 13],  omitting  those  terms  and  angles  which  are  usually  rejected  ; 


VII.i.>§,15.] 


DIFFEx'.ENTIAL  EQUATION  IN  t. 


effect    on    the    equation    of    the     perigee,    have    but    a  very    small    and 


521 

[5089'"] 


Terms  of    -iaiu  [4904]. 

whole  of    — 2(/')M 
— 'Mi\cQS.{2v—^mv) 


Terms  of    [5090e] 


— 2./3i'^e.cos.(2i' — 'imv—cv) 


—'Mi^e.cos.{2v—2mv+cv) 
— 2A.?^e'cos[2v — 2mv-\-c'mv) 

— 2A'-^''e'cos{2v — 2m« — cfmv) 


-2  Af^e'.  COS.  c'mv 


— 2^i''Ve'cos(2i'-2/)ii;-Ci)+c'?»t)) 
-2w3'i''ee'cos(2«-2OTi;-ci'-c'm«) 
— 2^f 'ec'.cos.  {cv-\-cmv) 
— 2Af'ce'  .cos.[cv — c'mv) 
— 2»4i'"e-2cos(2cj)— 2«+2«i') 
—2Afhy^.cos.{2gv—cv) 
-2A[^^''efcos{2v-2mv-2gv+cv) 

— 2^i'"'.-,.cos.(i— mt') 


3ni2 


1 


.cos.(2y — 2nir) 


4(l-m) 

21'«'-e'        ,^     ^ 
"4"(2=3"»7f°'(^'"^'"''-'^'"^) 

■.COS  (2u-2mî)-f-c  "îî') 


4(2-7n) 


12       -I    3 


-3e.cos.c« 


-|-3e^.cos.2co 

os.2^'-j; 
cos(2«-2/n?;) 


-\'l-y'^.cos.2gv 
3m2 
4(1— m) 


1(,.2 12 


— 3e.cos.CT 

-|-3!;^.cos.2fy 
— 3e.cos.c« 

3»!2 


4(1  —  ))! 

— 3e.cos.c» 
3ni2 


cos.(2f-2mi') 


4(1— m) 
— 3e.cos.cf 

— 3e.cos.c» 

— 3c. cos. cy 
— 3e.cos.cy 
— Se.cos.cu 
— 3c.cos.CT 
— 3e.cos.c« 
— 3c.cos.cy 
— 3e.cos.CT 
3nfi 


cos.(2y-2mr) 


VOL.  in 


4(1— m) 

131 


cos.(2y-2mi') 


IfiS 'v^ 


Terms  of  [5081  lines  5,  6]. 
—  2aSn     [4904] 


AllUioso 

Tonus 
liavo  tlio 
,     common 
3m2  „,  ,  \      factor 

.5f?>  i    a^.dv 


4(1— ,« 


2— 3i« 


^/a, 


>.ecos.cmv 


2— m 

— 2^.^»^  { èe2-iv2|  .cos  (2u-2mi'; 

,  ,    C  +cos(2t)-2mv-ciî)  ) 

+3Sfc.  ]  ^  ^i 

C  -\-cos{2v-2mv-\-cv)  ) 

C  +cos(2CT-2«4-2mD)  ) 

(_  +cos(2CT-|-2«-2;nj))  ) 

— t^|V.cos.(2o-y-2D+2Mi') 


3m2 


— .^S'^e.cos.cw 


4(l-m: 

-2^</i.(^cMv^)-e.cos(2«-2m'-CT) 
+003(21) — 2mv)         j) 
+cos(2ct-2«-|-2wî))  ) 
— 3.4/''e3.cos.(2i;— 2m'4-Cî)) 
+3.32®e3.cos.(2i;— 2/ni') 


+3^SV.- 


-Jj'.P^e'. COS.  c'mv 


'  4(1— wi 

-{-3A^^''eecos{2v-2mv-cv-\-c'mv) 
.       3m3 


,  ■Aj'^^e'  .cos.dmv 


'  4  (1— )« 
+3^Sj'"ce'.cos(2i'-2mf-cv-c'mt!) 

+3.4-ce'.|^'°"^^^+^''""^l 
1^+cos.(ct — c'mv)) 

— 2^f.(|e2— iy2).e'.cos.c'/nw 

4-3^fe2e'.cos(2y— 2my+c'mi') 

-[-3.5<'ieV.cos(2«— 2my  -  c'mv) 

-{-3Aft"e'.cos.c'mv 

-\-3Afc-e'.co5.dmv 

+3^i"'e='.  cos.(2y— 2/««— ct) 

+3A'^-'^th^.cos.2gv 

-\-3A[''''':'^y%cos{2gv-2v-\-2mv) 

1V'\—,.cos.[v — niv) 


4(1— m 
-2A'PK(lc^.i./-).-,cos.{v-mv) 


5 
6 

7 

8 

9 

10 

11 

12 
13 
14 
15 
16 


18 

19 

20 
21 
22 
23 
24 
25 
26 
27 
28 
29 
30 

31 
32 


Second 
part  ofxUn 
c.xurcssioti 

of  di. 


[5C90g] 


522 


THEORY  OF  THE  MOON  ; 


[Mcc.  ca 


[5089"]    insensible  effect  on  that  of  the  mean  motion   [5090c,  &c.]^ 


The  third  part  of    dt,     which  depends  on  the  second  power  of    a  5m,     is  contained  in 
[5081  line  7],  and,  by   neglecting  terms  of  the  sixth  order,  it  may  be  put  under  the  form. 


[5090^] 


a2.  dv 


e  .cos.cv 


We  shall,  in  the  first  place,  compute  the  first  of  these  terms,  by  means  of  [4904],  as  in  the 
following  table  ; 


Terms  of    aiu     [4904]. 
A'o°Kcos.{2v—2mv) 


TliirJ  part 
oi  the  ex- 
l)rcs.jion 

<.f  dt. 


A[^''e.cos.{2  V — 2  m  v — cv) 


[5090i] 


A'-^''e'.  COS.  (2  V — 2  mv-{-c'mv) 
A-^h'.  COS.  (2  V — 2  mv — dmv) 
Afhe'cos{2v-2mv-cv-{-c'mv) 

^î'^ee'.cos.  (2v-2mv—cv-c'mv) 
A[^'^\~.cos.(v — 7)iv) 


Terms  of    3.aôit     [4904]. 

3^^'".cos.(2t)— 2^1)) 

3.^i''e.cos.(2y— 2my— ct') 

3-4^^e'.cos.(2!,' — 2mv-\-c'mv) 

34i?'e'.cos.(2u— 2/ni'— c'mti) 

3A^'''K".cos.(v-mv) 
a 

3A.2^'>''.cos.{2v—2mv) 
3^'i'V.cos.(2u — 2inv—cv) 
3A'-^''ee'cos{2v-2mv-cv-{-c'mv} 
3A"''ee'.cos.(2v-2mv-cv-cmv) 
3Js^''\cos.{2v—2mv) 
3jl.2^'>\cos.{2v—2mv) 
3.^f/V.cos.(2t) — 27nv — cv) 
3^<'^e.cos.(2u — 2mv — cv) 
3^/»'.cos.(2y— 2mr) 


Corresponding  terms  of  the 
function  [5090/t  or  5081  line  7] 

^(A'"A^ 

iA':KJl['\e. COS.CV 

iAfKAf^c'.  cos.  c'mv 

§A'-^\A^h'.cos.c'mv 

^A(:\.^[''K-,.cos.{v—mv) 


a' 

sAl-KA['^e.cos.cv 


All  these  N 
lerm^  liiive 
the  factor 

a-.dv 


iA['\A['''é'e'co5.c\iv^°-' 


§A['KA'^''c^c'.  cos.c'mv 


^A^"\A?^e'.cos.c'mv 


§Af\A^*^e'.cos.c'mv 


lA[^\A['^eh'. cos.c'mv 


^A['\A^pe^c'. cos.c'mv 


HA["\A;''K-',.cos.{v—mv). 


«9.  dv 


I 

2 

3 

4 

5 

6 

7 

8 

9 

10 

II 

12 

13 

14 


[5090A;] 


This  table  contains  the  development  of  the  _^Ki!  term  of  [5090^],         ""'  .3.{aoti)^.       The 

second  term  of  [5090/i]  is  deduced  from  the  preceding,  by  multiplying  it  by  — 4e .  cos.  cv  ; 
but,  we  may  neglect  this  part,  because  it  produces  only  terms  of  the  fifth  and  higher  orders, 
and  of  the  forms  which  have  been  usually  neglected. 

In  computing  the  part  of  Q',    [50S2e — g],  we  have  neglected  the  term  depending  on 


VlI.i.'.MS.]  DIFFERENTIAL  EQUATION  IN  t. 

The  part  of   -,    which  is  not  periodical,  is  equal  to  -   [4828,&c.5095];      [5 


623 

090] 


hi   or  C   [5082c, &:c.,4937J]  ;  also,  that  part  of  (3(/,  which  depends  on  the  same  quantity  C 
[4937f,  A].    We  shall  now  compute  the  effect  of  these  terms,  noticing  only  those  arising  from 

the  variation  of  the  quantity  y  -^j— -^.  sin.  (au  —  2ii')     [5082rf],  which    is    the    most 

important  part.     From  this  we  get,  by  taking  the  variation  relative  to     &u' ,     6v', 

—  ^  -f"-^'-  '5«'.cos.(2i;-2.')-{-^4i].  f'^idv.sm.  (2v-  2v').  [5090„^] 

These  two  terms  of  Q'  are  equal  to  the  product  of  the  two  integrals  in  [4937e]  by    — \a.     posom] 
Now,   the   terms  of  [493Te]  are  developed  in  [4937m,  ç];    and  their  sum,  reduced  as  in 
[4937r,  Sec],  becomes,  by  retaining  only  the    most  important  terms,   which  increase  by 

integration,  o-- 

_ï^  .  ^  n  ç^6)_|_  çp)_  Qm  ^  _  g'_  COS.  i!mv.  [5090n] 

a  (J 
Multiplying  this  by  the  factor     — \a    [5090m'],  and  substituting,  for     ni  •  - ,    its  value    »r 

[5082/i'J,  we  get  the  following  expression  of  these  terms  of    Q'    [5090m]  ;  namely, 

lrr?.{'iCf^  C,3i— a'»>}.  e'.cos.c'm«.  [5090o] 

This  is  to  be  multiplied  by  the  conmion  factor     — \ — •   [5081],  and   the  product  added  to 

the  other  terms  of  the  second  member  of  this  value  of  dt.  Hence,  the  complete  value  of 
dt  is  found,  by  connecting  together  the  terms  of  [50905,^,  »,o].  This  may  be  reduced 
to  the  following  form  ; 

dt  =  function  [5082*]  X— ;—  +  function  [50906  omitting  line  1]  l 

—  function  [4904]  X  2.-^  +  function  [5090»- omitting  hue  1]  2    [SOOOp] 

+  function  [5090/]  +^"  .  |»r .{nq»)+ q»'— C^'CJ.e'.cos.c'mr.       3 

We  shall  use  this  expression  in  the  rest  of  this  article,  always  taking  the  functions  in  the  same 
order  in  which  they  occur  in  [SOSOjj]. 

*  (2896)   In  finding  the  chiefpart  of  the  secular  equation  of  the  mean  motion  in  [50S3,&c.] 

we  have  only  noticed  the  first  term      of  the  non-periodical  part  of    dt     [5082],  and 

*^"'  .  .  [5090g] 

have  neglected  the  remaining  terms  of  the  fourth  order,  which  are  evidently  much  less  than 

the  retained  part.      But  this  is  not  the  case  with  the  terms,  on  which  the  secular  motion  of 

the  perigee  depends  [4982,4979],  since  the  term  of  g'   [4974,  8.LC.],  of  the  fourth  order,    [5090?-] 

depending  on  the  square  of  the  disturbing  force,  is   as  great  as   any  other  of  the   retained 

quantities.     This  is   evident,  by  the  inspection  of  the  coefficient    of    e.cos.  cu      [4961], 

upon     which     — p  —  ce'-     depends     [4975].       For,    the    term     depending    on     A^^     [o090i] 


524  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5090']     and,  if  we  neglect  quantities  of  the  order   m\  this  coefficient  will  be*  — -. 

[5091]     We  then  have    -  = -.(1 — hn")     [4968];    which  gives    -  =  l  +  im^     and 

art,  0/ 

[5092]      — =  -   =  «^(l+im^)t.     Moreover,  we  have,  by  [695'],  n' ~  a'-.\/m'; 
therefore, t 

[4961  lines,  4999,  5158],  which  arises  from  the  square  of  the  disturbing  force,  is  as  large 
as  the  other  terms  of    q. 

*  (289T)     If  we  collect  together  the  terms  of    dt     [5090^], which  are  independent  of 

cfi.ih 
the  cosines,  we  shall  find,  that  they  all  have  the    common    factor     • — ; — •    ;         and     the 

quantities  connected  with  this  factor  are, 

l-j ?l!î^     [50825line  1]  ;         f'"'      JW  [5090-hne  2]  ; 

[5092a]  ^64.(1— ?«)2     •-  ^'     4(1— m) 

%{ •^'Cf^ii'^ff-  c^     [5090;  lines  1,7]; 
whose  sum  is  as  in  [5082].     At  the  epoch,  the  constant  term  of    —,    assumed  in  [4828] 
or  [5095],  is      ^  ;  putting  this  equal  to  the  fictor  of  dv,  in  [5082],  and  neglecting  terms  of 
the  fourth  order,  we  get     -  =  ^      [5090,5090]. 

t  (2898).     Neo-lecting  terms  of  the  fourth  order,  as  in  the  last   note,  we  have,  from 
[5093a]    [4968],     -  =  -.(1— iwr),     as  in  [5091].     This  gives     '^=\-\-^i,fi:     whose  square 

root,  multiplied  by     a-,     is 

^50031]  -^]  ==«*.(l+im^l  =  \     [5090'],  as  in  [5092]. 

Now,  by  neglecting,  in  [605'],  the  mass  of  the  earth,  in  comparison  with  that  of  the  sun, 
we  get     ?^  =  f^-.v/M;     and,  by  changing    n,     a,     M,     into     n,     a',     m',  respectively, 

[5093c]   ^^  ^^^^(.^j,^^^  j^jjjg  present  notation,  we  get     n'  =  a'"^.v/w',     as  in  [5092]. 

X   (2899)     Multiplying     together   the    values    of    -  ^  a^.(l+im2),      n'=^a'-.^m' 

[5093d]  .  r.ioon  "'  n-'./m'        ,   .    n\    c 

[5092],  we  obtain  the  expression  of    m     [4835],  or    -  =m=— ^  .(l+im-).  Squanng 


VII.i.<^15.]  INTEGRATION  OF  THE  EQUATION  m  t.  525 


^3    „,l 

-  =  m^  =  - 
n 

Hence  we  deduce,* 


—  =  m^  =  —j^.(l+lw')  =m  .(l+^rn^).  '  [5093] 


m  =  »i-.(l — km")  :  in.-  =  mr.  [5094] 

We  shall  now  suppose  the  value  of    ?iï  +  £     to  be  of  the  following  form  ;t 


this,  and  neglecting  terms  of  the  order     m^,  we  get  the  first  part  of  [5093]  ;  and,  by  using     [5093  i 
the  value  of  m    [4865],  we  get  the  last  expression  [5093]. 

*  (2900)     From  [5093],  we  have     m^  ^i  .{l-{-im^)  ;     dividing  this  by     (l+iî/i-),    [5094a] 
and  neglecting  terms  of  the  order     m*,     we  get, 

m=m''.{l—W)     [5094].  [509ib] 

Moreover,  by  substituting  the  value  of    l-\-im^     [5091],  in     m^     [5094fl!],  we  obtain  the 
second  equation  [5094]. 

t   (2901)     If  we  examine  the  functions  which  form  the  expression  of    dt     [5090p],  we 
shall. find,  that  it  is  composed  of  terms  depending  on  the  cosines  of  the  angles  included  in  the 
function  [.5095],  with   a  few  otiiers,  whicli  will  be  noticed   hereafter  [5239,5244,  fee.].     I^^^^^"! 
This   expression,  being  multiplied   by     n,     and  integrated,  gives  the  terms  depending  on 

the  same  angles   in   [5095].       Moreover,    the    expression  of    -— ,       has     the    constant 

dv 

term     -     [5090];     therefore,     ncit     contains  the  term     dv;     and,  its  integral    nt-{-s, 

the  term     v;     as  in  [5095  line  1].     Again,  the  expression  of    t     has  the  secular  term, 

3)ft2 

-—.fc'^.dv     [5086]  ; 
2"  [5095c] 

and,  by  multiplying  it  by     n,     we  find,  that  the  quantity    7it  +  s     contains  the  term, 

§m^.fe'^.dv.  [5095^,-, 

At  tlie  epoch,  when     e':=  E',     the  secular  terra  is  supposed  to  vanish  ;  and  this  is  effected 
by  putting  it  under  the  form, 

§mKfie'^-E"^).dv,  ^,095rf] 

and  making  the  integral  commence  with  the  epoch. 

VOL.  III.  132 


526  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

wi+5=î;-f  I  vf.f{e'~-E'').dv+  q»>.e.sin.  {cv—^)  1 

+q".e^sin.(2ct;— 2:=)  2 

+Cf'.e^sin.(3ct'— 3^)  3 

+  C^='.-/.sin.(2^ij— 2ti)  4 

+C^^).e7-.siii.(2§-t5— CD— 2^+^)  5 

+  Cf.sin.(2y— 2mv)  7 

+Cf>.e,sin(2«— 2/«i;— ct'+î=)  8 

e'ïà.rrf-                                                  +Cf>.e.sin.(2«— 2m^;+cr— ^)  9 

-]-C'-p.e'.ûn.{2v—2mv+c'mv—^')  10 

[5095]                                                    +C^"".e'.sin.(2z7— 2/«y— c'm«4-73')  H 

+  C<'".e'.sin.(c'mi'— ^')  12 

+C;'-'.ee'.sin.(2i)— 2mi;— c»+c'm«+K— ra')  13 

+C'/=).ee'.sin.(2r— 2mu— ci'— c'mi)+î3+ra')  14 

+C<"'>.ee'.sin.(cw+c'mt7— s — ^)  15 

4-C('='.ee'.sin.(cî; — c'm«— ra+^a')  1 6 

+  Ci"^'.e^sin.(2cw— 2?;+2/«2J— 2n)  17 

+  C('').7lsin.(2^i;— 2?;+2mw— 20  18 

+Ci"^'.e'lsin.(2c'«i«;— 2=:')  19 

+C''°'.-.sin.('«— »iii)  20 
a          ^ 

+Cf°'.  -.e'.%'m.(v — mv-\-c'mv — ra').  21 
a 

Then  we  shall  have,* 


*  (290'2)     Using  the    sign     2,     of  finite  integrals,  and  putting  any  periodical  term  of 

..  [5095]    under  the  form      C.sm.{iv-\-'^),     the  expression  of    nt-\-i     becomes  of  the  form 

I  i)uyu£/ J 

[5096i].      Its  differential,  multiphed  by     -=—      [5092f],  becomes  as  in  [5096f]. 
[50966]  «<+-=  =  v+^m\f{e'^-E'"-)  rf«+2C.sin.(«.+p)  ; 

[5096cJ  i/a,     *      '  -       ^  ^   '  V      1  W) 


VII.  i.  ^  15.]  INTEGRATION  OF  THE  EQUATION  IN  t.  52? 

15ra-  '>/('' 
C<°'= ^^ ^ ;  [5096] 


3._L  1  p^ -T  -,  9 O  /1(10) 


0 


3c 


2é 


-J— 2^^'^) 


4(1— m  )  "*~  2— 2m— c 


cr>= . 


[5097] 


Cf>=: i-    :  [5098] 


^'(4) 4  -^0  .  [5100] 

"^0  —      2g—c  ' 

C'-'^'m: i—  •  [5101] 

2g+c  ' 


-3m^(l +2^^-10'")  r      1+m  1-m       1)  ^ 

'  4(1— m)  '^'"'^•|2— 2ot— c"^2  — 2m  +  cj  ' 


Values  of 

c. 


V   -2J^>.(l+ie--iy-)+3Jr'-^''+3Jf  .e^ ^)_  2 

^"  -  2— 2/rt 


1 


8(a>:— 2+2ffl) \        ~  i    J  2  1  y  ^^^^^^ 

2_2»i— c 


Comparing  this  with  the  expression  of  (It  [5090p],  we  evidently  see,  that  the  coefficient 
C,  of  any  term  C'.sin.(it)-j-p)  of  the  second  member  of  [5095],  may  be  deduced  from 
the  term  depending  on  the  cosine  of  the  same  angle  in  the  second  member  of  [5090p],  by    L^"^°"] 

rejecting  the  common  factor    — — ,     and   dividing  by  the  coefficient     i,     corresponding 

to  the  proposed  angle     n'+p.      By  this  means,  we  obtain  the  values  of     CJ,"',      C*,",    &c. 
[5096 — 5116],  as   will    appear,   by   collecting    together   the  terms    of   the   six  functions     [5096«] 
[5090/^],  relative  to  each  of  the  angles  separately,  taking  the  terms   in  the  same  order  as 
they  occur  in  [5090p]. 

First.     Comparing  the  general  form     C.sm.(iv-\-p,)     [5096i],  with  that  depending  on 
Cf^    [5095  line  1],  we  get      C=C^^\,     i=c.     The  terms  of     C,    taken  in  the  order  in 


528  THEORY  OF  THE  MOON;  [Méc.  Cél. 

[5104]       C(a)^4.(l-»»)^    2-2,»+c '    ^        ' ^ ; 

^       ^      ^  2— 2/«+c 


[5105] 


^(9)^  4-(2->«) 


^'"'         2Jf>+3^f.e^ 


2 — m 

21ms 


[5106]     C(""=     "^'^^    ''^"'; 


_2JW+3J(^).e^ 


Values  of 


2    —  2— 3m 

C  3m^^^°'        _27m^  )      C  _7 1_  >  | 

^  ^         4        "^32.(1— m)  5  ■  i  2— 3m        2— m  >  / 

+  3.(A['^+Jf^).e'+3A['>.e^.(Af^+A^J')  \  4 

+  f  m^(ll.C'^'+2Cf— 2^"») /     .  5 


[5107]       C'/i)^ 


which  they  occur  in  [5032sline  27,  5090Mine2,5090o- line  11,  5090ihnes2,  6],  give, 
without  any  reduction, 

[5096/]  c.C  =  3m^.A[^^e-  2c.(l-lf)  +^-.JI,'k+iAi\^[^^e+^A['>\A['^e. 

Connecting  together  the  first  and  third  terms,  also  the  two  last  terms  of  the  second  member  ; 
substituting  also  C  =  C'°'>  e,  and  dividing  by  ce,  we  get  Q"'  [5096],  neglecting 
terms  of  the  order     m^.A^"e. 

Seco7id.     In  the  term  [5095  line  2],  we  have      C=  C'J''e'^,     i^2c  ,     and  then  we  get, 
by  connecting  the  terms  depending  on  tlie  angle    2cv,   in  [50906 line  11,  49041ine  11], 
[5097a]  -ic.l.^  e    :^  [^  -f-^e —^j  ).e — ^/i^    e. 

Hence  we  obtain  C^"  [5097].  In  like  manner,  Cj,~>  [5098]  is  obtained  from 
[50906  line  15]. 

Third.     In  the  term  [5095  line  4],  we  have      C^=Cl'''y^,     i=  2^;     and  the  terms 
in  [50906  line  13,  4904  line  13,  5090o-  line  29],  being  connected  together,  give, 

[5099a]  2g.C^Y={^+l<^''-i7'')-h^-^A^''7'+3Ai'''  e^7^  \ 

whence  we  get  [5099].     In  like  manner,  from  [50906  line  16,  4904  line  16],  we  obtain, 

{2g—c)  .q»ey^=—^e  7^— 2^<„'5)  ^  ^s . 


VII.  i.  §15.]  INTEGRATION  OF  THE  EQUATION  IN  t. 


Cf-^-- 


4.('2— HI— f) 


4.{-2—m) 


— 2J|«'+34^> 


'21wr 


Ci'="= 


21/»2.(2+3/h)  . 

4.(2— 3  m—c)       4.(2— 3/7i) 


-2Jr'+34^) 


2 — 3;« — c 


-2Jp'+3Jf    . 
— 2Jf)+3Jf   . 


C?^>= 


c — m 

3m^(I0+19m+8m2)  3m2.(l+?n) 


9m2 


S.(2c— 24-2m) 

— 3Jf>+3J("— 2Ji 


C(16)  =  - 


2_2m— c  .16.(1— »i) 

2c— 2+2m 


2c— 2+2m 


1 

2 


529 

[5108] 
[510!)j 

Values  of 

c. 

[5110] 
[5111] 


[5112] 


whence  we  get  [5100].     Also,  from  [50906  line  17], 

{2g+c).C^J'Uf=—ief-,     as  in  [5101]. 

Fourth.  In  the  term  [5095 line  7],  we  have  C^=C'f\  i^  2 — 2»?,;  and,  by 
connecting  togetlier  the  terms  depending  on  the  angle  2v — 2mv,  we  shall  obtain,  for  the 
expression  of  (2 — -2111). Cf\  the  same  expression  as  in  the  numerator  of  the  value  of 
C'^''  [5102].  For,  the  first  term  of  this  numerator,  with  the  factor  — 3;»-,  is  the  same 
as  in  [5082$  line  2]  ;  the  second  term,  with  the  factor  — 3m^e^,  is  as  in  [5090Jline  5], 
neglecting  terms  of  the  order  m^  e'*  ;  the  third  term,  with  the  same  factor,  is  as  in 
[50906  line  7].  The  terms  depending  on  ^["\  are  as  in  [4904  line  1,5090g- line  5]  ;  that 
connected  with  A[^\  is  as  in  [5090^  line  13]  ;  lastly,  that  depending  on  Jlf\  is  as 
in  [5090^  line  16]. 

Fifth.  In  the  term  [5095  line  8],  we  have  C^C'-^^'e,  i  =  2 — 2m — c  ;  hence  we 
get,  for  (2-2m-c).C-''e,  the  same  expression  as  is  given  by  [5103].  For,  of  the  two  terms 
of  the  first  line  of  the  numerator  of  [5103],  the  Jirst  is  found  in  [50906 line  3]  ;  the  second, 
in  [.5082s  line  3].  The  first  term  of  the  second  line  is  found  in  [50906  line  10]  ;  the  terms 
depending  on  A['\  are  in  [4904  line  2,  5090^  line  12]  ;  that  on  ^™,  in  [5090^  line  6]  ; 
lastly,  that  on    A["\    in  [5090^  line  28]. 

Sixth.  In  the  term  [50951ine9],  we  have  C=C'^h,  i=2 — 2m4-c;  hence  we 
get,  for    (2 — 2m-\-c).  Cf'e,    the  same  expression  as  is  given  by  [5104].     For,  the  first  term 

VOL.  III.  133 


[5102a.] 


[5103a] 


[5104a] 


53P  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

^.-,113^     It  would  seem  as  if  this  value  of     C['''^     ought  to  be  of  the  order  zero  ;  for, 


of  [5104]  Is  obtained  from  [5090i  line  4],  neglecting  quantities  of  tiie  order  vi^e^  ;  the 
second  term  from  [5082s  line  4]  ;  the  third  term  from  [4904  line  3]  ;  the  fourth  from 
[5090^1ine7J  ;  the  fifth  from  [5090^ line  15]. 

Seventh.     In  [5095 line  10]  we  have      C  =  Cf e',     i=z2—2m+c'm  =  2—m,    nearly  ; 

,„-  -,     hence  we   get     (2 — ni^.Cf'e',    corresponding    to    [5105].     The   terms    being   found    in 

[5032s  line  6,  4904  line  4,  5090O- line  24],  respectively.       In  like  manner,    [5095  line  11] 

gives     C^a^^'V,     ^■=2— 2m— c'ot=:2— 3/«,  nearly;  and  the  terms  of  (2—3/»).  C^^'e' 

are  found  in  [5082s  line  5,  4904  hne  5,  5090^  line  25]. 

Eighth.     In  [5095  line  12]  we  have      C=  Ci'"e',     i=^c'm^^m,     nearly;    hence  we 

[5107rt]     ggj     ?«.C^"'e',     corresponding  to  [5107].     For,  by  comparing  the  terms  of  the  five  lines  of 

the  numerator  of  [5107],  with  those  in  the  preceding  functions,  we  shall  find  that  they  agree, 

as  will  appear  by  the  following  examination.     The  terms  in  [5082s  lines 23,  24]  give  those 

in  [5107  line  1].     Those  in  [5082s  line  25,  5090^ lines  3, 4]  give  [5107  line  2].     The  terms 

in  [5090^- lines  17,  19]  are     -^-—^.{Af-^A-^^),      as  in  the  first  term   of  [5107  line  3]. 

The  two  terms  in  [5090nines  3,10]  make  ZÂfK  Af'>  ;  and  those  in  [5090ilines4, 11], 
3^„'".^!,""  the  sum  of  these  two  expressions  is  ^A.^'^\{A^^'^-\-AiP),  as  in  the  second 
term  of  [5107  line  .3].  In  [4904  line  6]  we  have  —2Af\  and,  in  [5090i,'-line  23], 
— 2^^5).(i(;a_iy3)  ;  whose  sum  is  — 2.4^5'. (l+i-e^—iv^),  as  in  [5107  line  3].  The 
terms  depending  on  A^\  A[o''  [5090jg-  lines  26, 27],  give  those  in  [5107  line  4].  The 
sum  of  the  two  terms  [5090t  lines  8,12]  gives  3A['\A['^'e^;  those  in  [5090»  lines  9,  13]  give 
3^<''.-47'e^;  the  sum  of  these  two  expressions  is  3A[^hK{A[''''-\-A['''),  as  in  [5107  line  4]. 
Lastly,  tlie  terms  depending  on  Cf,  Cf\  C^'»'  [50902jline3],  give  the  terms  in 
[5107  hne  5]. 

JYinih.  In  the  term  [5095 line  13]  we  have  C=:C['-''ec';  i=2— 2/»— f-j-('ï;i=2— ?n— c, 
nearly  ;  hence  we  get  (2 — tn — c).C[''^ec',  corresponding  to  [510S].  For,  the  four 
[5108a]  terms  of  tlie  numerator  of  [5108],  correspond  respectively  to  [5082s hne  9,  50906  line  9] 
and  [49041ine7,  5090^- line  18].  In  like  manner,  [,5095 line  14]  gives  C^Cfee', 
(  =  '2 — 2:71 — c — cin^=2 — 3m — c,  nearly;  corresponding  to  [5109]  ;  the  four  terms  in 
the  numerator  being  obtained  from  [5082s line  7,  5090J  line  8,  4904 line  8,  5090^  hne  20]. 

Tenth.     In  the  term  [5095  line  15]  we  have  C  =  Cl^^^'ee',     i=  c+c'm  =  c+m,  nearly; 
hence  we   get     {c -\- m)  .  C[^*^  e  e' ,     corresponding   to     [5110];     the   two    terras  of  the 
'       numerator  of    C','^*     being  deduced  from  [4904  line  9,  50905-hne  21].     In  like  manner,  we 
get  [50951ine  16  or  5111]  from  [4904  line  10,  5090^1ine  22] . 

Eleventh.     In  the  terra  [5095  line  17]  we  have     C=  C['^^e^,     i  =  2c-  2+2m  ;    hence 


vil.  i.  s^MÔ]  INTEGRATION  OF  THE  EQUATION  IN  t.  531 

its  numerator  contains  several  terms  of  the  order     m,*     and  its  divisor  is  of    [5112] 


we    get      {2  c — 2 -|- 2»i) .  Cf"'' t-,      corresponding     to    [5112].        For,    tlie    terms    in 

[50SJ*  lines  10,  11,  12]  give  the  first  term  and  two  last  terms  of  the  numerator  of  [5112]. 

In  [50906 line 6],  we  get  the  term  of  [ôll2Iinel],  having  the  factor     (1+'")  ;     and  in     [5119a] 

[50906  line  12]  the  last  term  of  the  same  line  ;    in  [.^OSO^-linesS,  14],  the  terms  depending 

on     Ai\     A[''>;     in  ['1904  line  12],  the  term  depending  on    A\^^\ 

Twelfth.  Inthe  term  [5095 line  18]  we  have  (■=^C['~'j^,  i=2^— 2+2m;  hence 
we  get  (2g — 2-J-2»i). Ci'''7^,  corresponding  to  [5113].  For,  the  terms  in  [5032«] lines 
13,  14,  give  the  first  and  last  terms  of  [5113].  In  [50906  line  14],  we  get  the  second 
term  of  [51 13],  neglecting  terms  of  the  fourth  order  [5112'"].  In  [4904  line  14]  we  have 
—  2.'J,'->  ;  and,  in  [.5090^ line  10],  the  term     — 3^^"',     as  in  [5113]. 


[5n.3o] 


Thirteenth.  In  the  term  [5095  hne  1  9]  we  have  C  =^  Ci^^h'^,  i  =  2c'm^2m, 
nearly;  hence  we  get  2  m  .C','**'e'-,  corresponding  to  [5114].  For,  the  term  in 
[49041ine  1.5],  gives— 2^^'V2;     whence  we  get      Cf>    [5114].  [BlUa] 

Fourteenth.     In  tlie  terra  [5095  line  20]  we  have      C=C[^^K-,      i=:l  —  m  ;     hence 


we  get     (1 — m).C['^K-,     corresponding  to  [51 15].     For,  the  first  term  of  [5082«  line  19]     [susa] 

gives  the  first  term  of  the  numerator  of  [5115].      The  terms  in  [SOSSs  lines  20,21]  give 

'3m-.  ./3""' 
-r-^ — ^.(4+4m);     adding  this  to  the   term  deduced  from   [5090o- line  31],  namely, 

— '- — ^,     the  sum  becomes    ; !— — .(5-)-4«!).     This  difiers  a  little  from  the  author, 

4(1— m)  4(1— m) 

who  makes  the  factor  equal  to  5-j-3?H,  instead  of  5-{-4m.  The  term  [4904  line  18] 
gives  —2A['''';  and  [5090°- line  32]  gives  —2.A\'''\{le^—ly^);  the  sum  of  these  is 
— 2A'^~'>.{l-\-^e^ — iv^),  as  inthe  third  term  of  [5115].  Lastly,  the  sum  of  theterms  in 
[5090nine3  5, 14]  gives     3A<-p.A[''\     as  in  [5115]. 


[51156] 


a 
a 

a 

"        a     .      __  ,         .  ._....-  [5H6a] 

a' 


Fifteenth.     In  [5095 line  21]  we  have      C  =Cf '>'>.-,. e',    i  =  1— m  +  c'm=  1,  nearly; 
hence  we  get     Cf^K-.e',      corresponding  to   [5116];     this    term    being    deduced   from- 


[4904  line  19],    — 2^««.-.e'.     Hence,  the  values  of  C;;",   C['\   &c.  [.5096— 5116]  agree 

with  those  given  by  the  author,  except  in  the  small  term  of  the  fourth  order,  mentioned  in 
[51156]. 

*  (2903)     The  two  terms     3j1[^\     2A["\    of  the  numerator  of  the    value  of    €/»" 


632  THEORY  OF  THE  MOON  ;  •  [Méc.  Cél. 

the  same  order.  But,  we  have  seen,  in  [4855],  that  if  we  retain  only  the 
first  power  of  the  disturbing  force,  the  value  of  C<"^'  cannot  have,  for  a 
divisor,  the  square  of  2c — 2-f  2m  ;  it  must,  therefore  happen,  that  all  these 
terms,  taken  together,  destroy  each  other,  except  in  quantities  of  the  order 
m;  which  is  a  fact  confirmed  aposteriori  by  calculation.  Hence  it  follows, 
that,   in    the  values  of    J<''     and     J<"'     [4999,  5009],  in  the   expression 

[5112"']  of  Cj"^'  [5112],  we  OM^A^  to  re/ed  i/je  ie/ras  depending  on  the  squares  of  e, 
e'  and  y.  Each  of  these  terms  introduces  in  C{'°'  quantities  of  the  order 
e^  ,•  while  their  sum  produces  only  a  quantity  of  the  order  me^,  which  we 
may  neglect.*   There  is,  therefore,  a  disadvantage  in  retaining  only  a  part  of 

[5ll2'v]    jj,ggg  terms,  and   it  is  best  to   reject  all  of  them.       This  is  one  of  those 
to-  singular  cases  of  approximation,  in  lohich  ive  deviate  more  from  the  truth,  by 
noticing  a  greater  number  of  terms. 

We  then  have. 


[51166]  [5112],  are  of  the  order  m  [4999,5009],  and  the  denominator  2c— 2-f-2,77,  of  the 
same  expression  [5112],  is  also  of  the  order  m,  being  very  nearly  equal  to  2m — Sm" 
[4828e]. 


Remark; 
ble  case 
approxi 
ntion. 


[5116c] 


*  (2904)  Several  terms  of  the  order  e^,  e'^,  7-^,  have  been  neglected  in  the 
investigation  of  the  analytical  expression  of  C/*"'  [5112]  ;  as,  for  example,  the  factor 
l-|-|e^ — \y^ — 1^'^  [50906 lineG]  is  omitted  in  [5112a];  hence,  it  becomes  necessary, 
I'llGJl  "P°"  ^''"^  principles  adopted  in  [5112'"],  to  reject  terms  of  the  order  e~,  c'^  y~,  in 
computing  the  values  of  A'-^\  Ap,  Jl[;''\  ^<'",  &c.,  which  are  to  be  used  in  [5112]. 
Therefore,  if  the  expression  of    A'^     be  deduced  from  [5009],  and  put  under  the  form 


[51l6e] 


^tul_3^;.  ^.  I  /,^+  he^Jr1c/^+  Kf  }  ; 


tj  being  independent  of    e,     e',     y,     we  must  use 

a, 

in  finding   the  va'ue  of  A'-^^    [5212,5112];    observing,  that  the  terms     k^,     Jc^,     kc. 

have  the  divisor     2c — 2+2w     in   [5009  lines  1,2]  ;  and  this  introduces,  in    C|"'     [5112], 

[5116a-]  2^'"' 

the  divisor     (2c — 2-f  2w)2,     by  means  of  the  term     — -— !— — ,     &c.       Now,    as  a 

xc — x-f-^m 

divisor  of  the  order  (2c— 2-(-2m)-  cannot  occur  in  the  first  power  of  the  disturbing 
[5116A]    forces  [4855],  it  is  necessary,  that  the  terms  of  which     l\     is  composed  should  mutually 

balance  each  other,  so  as  to  reduce  it  to  the  order  m.  The  same  is  to  be  observed  relative 
[5116i]     to     k^,     k,,     1%,     Similar  remarks  may  be  made  upon  the  value  of     Q"''     [5113],  and 

upon  those  of    Ai'\     A,"",     A\'^\      B'-'^,     &c.,  which  occur  in  [51 12,  5113,  &ic.]. 


VII.i.§i6.]  INTEGRATION  OF  THE  EQUATION  IN  ï.  538 

^(„,  _  8(90— 2+2m)        16.  (!-;«)        "^     '  ^     ^  2g--2+2m  [s^g^ 

We  must  apply  to  this  value  of     C['''     a  remark  analogous  to  that  made  on     [5ll3'j 
C(i5)     [5112'— 5112'^].     Lastly,  we  have,  v.iue.of 

e(i6)^_f?_    .^  [5114] 

'  m 

„,_  )8.(l-m)^    4.(l->»)  ■  ■       ^        -  4/;i-       .         .     ^  ^^^^^^^ 

'  1  —  m  ' 

CÇ30)  ^  _  2  J('8).  [5116] 

16.  We  shall  now  determine  the  numerical  values  of  these  different 
coefficients.  For  this  purpose,  we  shall  remark,  that  we  have  by 
observation  ;* 


ohserVQ- 
tjoii. 


[5117] 


m=  0,0748013;  log.  m  =  8,8739091.  Da,afr,.n. 

c  =  0,99154801  ;  log.  c  =  9,9963137. 

g=  1,00402175;  log.  ^  =  0,0017431. 

e'==  0,016814,  at  the  epoch  of  1750;  log.e'=  8,2256710. 

y  =  0,0900807  =  tang.  5''  8"  50',4  ;  log.  7  =  8,954631 8. 

According  to  observation,   the    term     C''^\e.sm.(cv — to)     is  nearly  equal  to     rsjigi 
— 22677^5. sin. (ctJ — to)     [5574].      We  have  given  the  analytical  value  of 


*  (2905)  The  values  [5117]  agree  very  nearly  with  Burg's  tables  ;  observing,  that 
the  moon's  motion  is  represented  by  v  ;  the  motion  from  the  perigee  is  cv,  and,  from  [^'l'''] 
the  node,  gv  [4817]  ;  the  sun's  motion,  neglecting  the  periodical  terms,  is  mv 
[4835,4836].  The  excentricity  of  the  solar  orbit  is  represented  by  e';  it  is  the 
same  as  e"  [4030],  taken  to  six  places  of  decimals  ;  the  neglect  of  5,  in  the  eighth  decimal 
place  of  e',  produces  a  small  difference  in  the  logarithm  of  e"  or  e,  given  in 
[4080,5117].      Lastly,   y   represents  the  tangent  of  the  inclination  of  the  lunar  orbit  to  "^^ 

the  apparent  echptic  [4813,  4818, &ic.].    The  value  of  m  [5117]  gives    m^  =  0,0055952,    [5117rf] 
which  is  frequently  used  in  this  volume. 

VOL.  III.  134 


634  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5119]      ^(0)     in  [5096]  ;  and,  if  we  substitute  in  it  the  values  of    A[°\     A'-^',     given 
Assumed^    by  a  first  approximation,  we  obtain,* 

[5120]  e  =  0,05487293. 

This  value  is  sufficiently  accurate  for  the  determination  of  the  coefficients 
Af\  JJ",  Jf,  &c.  We  have  supposed,  in  conformity  with  the  phenomena 
^^^  ^  of  the  tides,  that  the  moon's  mass  is  y|y  of  that  of  the  earth. f  This 
being  premised,  the  equations  between  these  coefficients  [4998 — 5017, 
5062—5077]  become,î 

[5122]  J(»)  =0,00723508— 0,00501814.{£i'"—5y>|; 

[5123]  J_»  =  0,204044— 0,0660894.4°'— 0,0480577.  { Bf—Bf>  \  ; 

[5124]  Jf  __  0^00372953; 

[5125]  J(3)  =_o,00315160— 0,00449610.fi<^>; 

[5126]  4')  =  0,0289026— 0,00564793.5<'°>  ; 

[5127]  J_6)  =— 0,193315+0,104996.J;"+0,372796.4«); 

[5128]  ^(-)  =  0,538027+0,0334044.Ji"+0,135144.^p) . 

[5129]  ^(8)  =  —0,0908432+0,139071.^1"— 0,280299.  Jp'  ; 

[5130]  ^(0)  =  0,0791 193+1,055799. J<')+0,270902. Jf  ;§ 


[5120a] 


*  (-2906)     The  assumed    value   of    e     [5120]    differs  but  very  little  from  that  finally 
adopted  in  [5194]. 


[.5121a]  "t"  (2907)  This  value  agrees  nearly  with  the  result  obtained  in  [4.321]  ;  the  author 
afterwards  decreased  it  to     t-j.^j^      [4631  « — J]. 

X  (2908)     The  equations  [5122—5140]  are  obtained  from  [4998—5002,5004-5017], 

by  taking  them  in  the  same  order,  and  dividing  by  the  coefficients   of    »4o"",     A'-^\     -^é^\ 

[5122a]    §jc.  respectively.     The  equation  [5003]  is  afterwards  used  in  finding     ^^5)     [5205]  ;    and, 

in  like  manner  the  equations  [5141—5156]  are  derived  from  [5062-5077],  using  the  values 

[512261  of  m,  c,  g,  e',  y,  e  [5117,5120];  also  — ^  ==??i^  [5082^'].  Upon  examination 
it  will  be  found,  that  the  numerical  results  obtained  by  the  author  are,  in  general,  very 
correct  ;  the  differences  being  rarely  more  than  one  or  two  units  in  the  last  decimal  place. 
The  few  cases,  in  which  a  greater  difference  was  discovered,  will  be  mentioned  in  the 
following  notes. 

■^  (2909)     It  will  be  found,  by  examination;  that  the  coefficient  of  .^'^'K  in  this  equation, 


VII.  i.^  16.]                       COMPUTATION  OF     ^(."'',     B;.""),     €<."•>.  635 

jc^'»)  =  0,00285368— 0,0041501 8. /?(">;  [5i3i] 

J<")  =  0,366100— 0,01 72.338.  J'/'— 0,259744.4'")— 0,324680.  (^i'>)';  [5i32] 

Jf'  =  0,00265066  ;*  [5i33] 

4^')  =  0,0523335—1 ,555935.S<»>  -0,22021  G-A"^^'^  ;  [5i34] 

4»)=— 0,0129890;  [5135] 
4'5)  =.  — 0,1007403+0,0385084.4"+2,09016.^î'=" 

[5136] 

—  1,022473.  Jf)—36, 11 032.^5^^)— 5S°'.£^=' I  ; 

4'^'  =  0,114623+0,166591.4"^'— 5,07811.5^^);  [5137] 


Fuiid.i- 


4")  =  — 0,121028t+0,937593.4°'— 0,000031563.4'«>  eTua",L 

[5138] 

—  0,  1  39767 .  {  Bi''^+Bi^'^  ]  ;  ">  le.er  J 

'                            i        2         '         2        J  '  mine  .4,5. 

4^'  =  1,208124+1,018700.4'"'— 5,074801.4'^'  ;  [5i39j 

4>3)  =  —  0,121 295+0,675879.  Ji'^'+0,183834.4'«'  ;  [5140] 

^f"'  =  0,0287031— 0,0574772.4"'+0,000432665.4"  ;  [shj^ 

5y'  =  —0,00000236395  ;  [5142] 

Bf  =-0,00564433+0,0048210.5»';  [5143] 

Bf  =0,0166486+0,0166486.4"- 0,0165194.5;"';  [5144] 

5'^'  =  0,00656716—0,00708386.5;°'  ;  [5145] 

5f'  =  0,0000147361—0,00681821.4'  ;  ^5146^ 

5f  =—0,0183098— 0,01700]3.{4"—5("'|;  ^gj^^^ 

5i"  =  0,0809777+0,0249192.5^'— 0,0478194.5'""  ;  ^gj^g^ 

5(8,  _  —0,0868568+0,1 87099.5f'+0,0556224.5'/'  ;  ^5^4^^ 

5(9)  =  —0,0263090— 0,0787687.5',°'+0,0506541 .5f'  ;  ^g^g^] 

5[""  =  0,0712575— 0,03047765.5(,'"+0,021 1 192.5</>  ;  ^gjgj^ 

ought  to  be  increased  about  one  tenth  part  ;  but,  as  this  difference  does  not  materially  affect 

1                 •      •       1         r •  [5130al 
the  results,  no  notice  is  taken  oi  it. 

*  (2910)     Upon  repeating  the  calculation  of  this  value   of    A^^"^,     it  is   found  to  be 

greater   by  about  -^-^  part,  or  five   units  in  the  sixth  decimal  place.      This    difference  is  l5133a] 
unimportant. 

t  (2911)     The  numerical  values  of  the  coefficients   [5138]  agree  with   the  equation 
[5015].     A  very  small  change  in  the  constant  part     — 0,121028     would  be  made,    by 

introducing  the  term  depending  on     — §7^     [496 Ih]  ;  but  the  effect  is  insensible.  [5138a] 


536 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


5;">  =  0,421270+0,842540.4"— 0,337016.  J<'^'+0,586564.£1'" 

[5152] 

+0,157666.5f); 
[5153]  ^('2)  =  0,000194141— 0,168403.4"+0,0673614.  S  Ji")+i5<"'j; 

[5154]  5('"  =  0,0847889+0,147896.{4')—i5;'"}— 0,0591586.4"^  ; 

[5155]  5^")  =  — 0,01 2561 9; 

[5156]  5f'  =  0,00386625. 

From  these  equations,  we  have  obtained  the  following  values  ;* 

[5157]  4«'  =  0,00709262  ; 

[5158]  4')  :=  0,202619; 

[5159]  4='  ==  —  0,00372953  ; 

[51 60]  43)  =  _  0,00300427  ; 


[5156o] 

[5156i] 
[5156c] 

[5156rf] 

[5156e] 

[5156/] 
[5156g-] 

[5156;i] 


*  (2912)  Substituting  the  value  of  B^^^  [5142]  in  [5122],  we  obtain  a  linear  equation 
in  ^'"i  -Si"'-  Combining  this  with  the  four  Knear  equations  [5123,5141,5146,5147], 
containing  the  five  unknown  quantities  ^'^\  A'^\  B[°\  B^\  B^^'',  we  obtain  Jive  linear 
equations  ;  from  which  we  may  deduce  these  five  unknown  quantities, by  the  usual  rules,  as 
in  [5157,5158,5176,5181,5182].  Substituting  these  values  in  [5143,5144,5145],  we 
get  Bf\  B^^\  B^^  [5178—5180].  Using  the  value  of  B[''>  [5176],  we  obtain 
from  [5148,5151]  two  linear  equations,  for  the  determination  of  ^7'=  ^î'°'  [5183,5186]; 
and,  from  [5149,5150],  two  linear  equations,  to  find  B'f\  Bf>  [5184,  5185].  Hence 
we  easily  obtain,  from  [5125,  5126],  the  values  of  Af\  4^'  [5160,  5161].  Substituting 
w^l"  [5158]  in  [5128,  5129],  we  get  two  linear  equations,  to  find  A'-p,  4«  [5163,5164]; 
and,  in  like  manner,  [5127,5130]  give  Af\  Af'>  [5162,5165].  We  may  remark, 
that  these  values  of  Af\  Af\  are  both  affected  by  the  small  correction  [51o0o]  ;  but 
the  effect  of  this  correction  is  insensible.  Substituting  the  values  of  A'i\  B\''^ 
[5158,5176]  in  [5131,  5132,  5152,  5153],  we  get  four  linear  equations,  for  the 
determination  of  .^<'<»,  .4<"i,  SJ,"',  B['-''  [5166,5167,5187,5188].  Substituting 
4'2)_  jB'^)  [5168,5176]  in  [5134],  we  get  A['^^  [5169].  Substituting,  in  [51.36,5137], 
the  values  of  A[^\  A^^^\  &c.,  which  we  have  already  investigated,  we  obtain  two 
Ztnear  equations,  for  the  determination  of  ./3o''^^  ./3*"'  [5171,5172].  In  like  manner, 
the  three  equations  [5138 — 5140],  are  linear  in  A['''\  A^^^\  A\^\  and  give  their 
values  [5173,  5174,  5175]  ;  which  would  be  altered  a  little  by  the  introduction  of  the 
correction  [5138a].  This  correction  is,  however,  quite  unimportant.  Finally,  with  the 
values  we  have  already  computed,  we  easily  obtain,  from  [5154],  that  of  i?','^'  [5189]. 
This  completes  the  investigation  of  the  series  of  terms  contained  in  the  equations 
[5157—5191]. 


Vll.i.§16.]  COMPUTATION  OF    ./?„«",    B'ir\     CTl  537 

[5161] 
[5162] 
[5163] 
[5164] 
[5165] 
[516G] 
[5167] 
[5168] 
[5169] 
[5170] 
[5171] 
[5172] 

Values  of 

[5173] 
JÎ,  B. 

[5174] 

[5175] 

[5176] 

[5177] 

[5178] 

[5179] 

[5180] 

[5181] 

[5182] 

[5183] 

[5184] 

[5185] 

[5186] 

[5187] 

[5188] 


4''  = 

0,0284957  ; 

A'^^  =- 

-0,0698493  ; 

A['>  = 

0,516751  ; 

Af^   =- 

-0,207510; 

yif  = 

0,274122; 

Jf  = 

0,00081065; 

jni)  = 

0,349068  ; 

4"'  = 

0,00265066  ; 

J(I3)  _ 

0,0075875 , 

4"'  =- 

-0,0129890; 

4-)  =- 

-0,742373  ; 

^(16)  =_ 

-0,041378  ; 

^<>''  =- 

-0,113197; 

4«'  = 

1,08469; 

^(19)  = 

0,001601; 

5<«)  = 

0,0283831  ;  ,' 

5^>'  =- 

-0,00000236395; 

jBf  =- 

-0,00550748  ; 

^f'  = 

0,0195530; 

B',''  = 

0,00636608  ; 

£(5)  =. 

-0,00136676; 

/?f  =- 

-0,0212720; 

B'-p  = 

0,0782400  ; 

B['^  = 

—0,0833684  ; 

Bf^  = 

0,0327678  ; 

Bf)  = 

0,0720448  ; 

£(..)  = 

0,491954; 

^(12)  = 

0,0061023; 

VOL.   Ill 


135 


538 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[5189] 
[5190] 
[5191] 


[5192] 


[5193] 


Corrected 
value  of 

e. 
[5194] 


[5195] 
[5196] 
[5197] 
[5198] 
[5199] 
[5200] 


5;")  =  0,0920621  ; 
iJ(H)  __0,0I256]9  ; 
Bf^  =     0,00386625. 

By  means  of  these  values,  we  have  corrected  the  expression  of    e     [5120], 
making  use  of  the  equation,* 

q''e=  — 22677%5. 
The  expression  of     C^"'     [5096]  gives, 

C(0)    _  —2,003974; 
hence  we  obtain, 

e  =  0,05486281  ;  log.e  =  8,7392781  ; 

which  differs  but  very  little  from  the  value  before  used  [5120].       Then 
we  find,t 

q»  =  0,752886: 
Cf  =—0,336175: 
C„3)  =  0,243118: 
q^)  =  0,722823 
e(5)  =—0,250034: 
Cf)  =—0,00919876; 


*  (2913)     Comiiaiing  the  expression      C^''e.s\n.(cv — ra)     [5095  line  1],  with  its  value, 

[5192a]    deduced    from    observation,     — 22677%5.  sin.  (cv — zs)     [5574],    and  adopted    in   Burg's 

tables  [5574a],  we  get  the  expression   of     C^^'e     [5192].       Now,  substituting  in  [5096], 

the  values  of    m,     c,     y,     .4«>,     ^i"     [5117,  5] 57,  5158],  we  get  the  value   of     C^"» 

[51926]    [■5J93J .  jjnd  (^en,  from  [5192],  we  obtain  the  corrected  value  of  e  [5194]. 

t  (2914)  Substituting  the  values  [5117,5157—5175,5194],  in  [5097— 5106],  we 
get  [5195— 5204].  Having  thus  obtained  Cf,  Cf,  C^"»  [5200, 5203,  5204],  we 
[5195a]  j^^^y  gQj^^^jy^g  .^f  [5205],  by  means  of  the  formula  [5003].  The  values  C','",  C','=', 
Cp\  are  derived  from  [5107,5103,  5111],  which  contain  A'f,  Jlf';  but  the  effect 
of  the  correction  [5156(/]  is  insensible.  The  expressions  [5208,  5209],  are  deduced  from 
[5109,5110]. 


VII.  i.sM6.]                      COMPUTATION  OF     A\r\    B„"'\     Cf-  539 

C<-p  =_  0,4 14046;  [520i] 

Cf  =     0,0129865;  [5202] 

Cf  =     0,00392546;  [5203] 

q'»)  =—0,0387853;  [5204] 

JÇ5)   =—0,00571628;  [5205] 

C.")=      0,196755;  [5206] 

C['~^  =     0,127650;  [5207] 

C('^)=_  1,081734;  [5208] 

C<"')=      0,373115;  [5209] 

Cf'=  — 0,616738.  [5210] 

We  must,  by  the  preceding  article  [51 12'",  51 13'],  in  calculating  the  values  of 
ç.(i6)^  C,"',  use  the  values  of  A['\  J<"\  A[''''\  determined  by 
nefflBcting  the  squares  of  the  excentricitj  and  inclination  of  the  lunar  orbit. 
We  have  thus  found  the  following  values  of  J<'>,  J(">,  J<")  and  Bf\ 
which  must  be  used  in  this  calculation  ;* 

4"  =  0,201816;  [5211] 

4")^  0,349187;  [5212] 

jn3)=  0,0077734;  [5213] 

B(o)  =  0,0282636  ;  [5214] 


hence  we  deduce, 


q'°'  =  0,272377  ;     .  [5215] 

C('^>  =  0,033825.  [5216] 


*  (2915)     The   principles    upon    wiiicli   these    quantities   are    neglected    have    been 
explained  in   [511-2',  &c.;  51 16c— ij.     The  quantities     ^^%     .4™     [5157,5166],    being     [5211a] 
very  small,  tlieir  corrections  are   unimpartant  ;  and  the  author  seems  not  to  have  noticed     [52116] 
these  corrections  in  [5211,  S>:c.].     The  calculation  of  the  terms  [5211 — 5216]  is  made  in 
the  following  order.     Af  is  given  by  [4993]  ;  then     A\'\  by  [4999]  ;     ^V»',      A[}^'',  by      ^^gjj^^ 
[5008,  .5010]  ;    .^(">,   by  [5009]  ;     JSj%  by  [5032]  ;  and  .^i'^)^  by  [5011].     The  values 
thus  found,  differ  but  little  from  those  in  [5211 — 5214];  and,  by  substituting    them    in     '^  - 

[5112,  51 13],  we  get  [5215, 5216],  neglecting  always    e^,    e'^    f. 


540  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Then  we  have,* 
[5217]  Cr  =     0,173647; 

[5218]  Cr  =     0,236616; 

[5219]  Cf'  =-2,16938. 

This    being    premised,   the  expression  of     nt  +  e     [5095],    becomes,     by 
reducing  its  coefficients  to  seconds,! 

nt+s  =  v+^,m^f(e'^—E").dv  1 

—22677^5    .sin.(c«— 33)  2 

+     467%42.sin.(2c«— 2^)  3 

—  1 1',45  .  sin.  (3cD— Ss:)  4 
+  406',92  .  sin.(2^v— 20)  5 
+       66^37.sin.(2§-i;— ct-— 2^+^)  6 

—  22%96.sin.(2^-2;+cf— 2c'— ^)  7 

—  1897%38.sin.(2w— 2m?;)  8 

—  4685^^45.  sin. (2u—2w?f—ci-+^)  9 
+  146^96.  sin. (2f—2m«;+ctJ—^)  10 
+       I3',6l  .  sm.(2v—2mv+c'mv—z/)  H 

—  134',51  .  sm.(2v—27}iv—c'mv+^')  12 
+  682^37.  sin. (c'mv—T;^')  13 
+       24',29.sin.(2«;— 2mf— cz;+c'7ni'+-— ^')  14 

—  205%82.  sin.(2«— 2mii — cv—c'mv-\-^-{--!^')  16 
+       70%99 .  sm.{cv+c'mv—-—'/)  16 

—  117^35.  sin.  (cî; — c'mv — tô-f^')  17 
+  169'10.sin.(2c2;— 2v+2mtJ— 2î:)  18 
+  56',62.sin.(2^f— 2«+2mr— 20)  19 
+  10',13.  sin.(2c'mv— 2^')  20 
+  122',014.(l+z).sin.(f— mil)  21 
—       ld%809.(\-\-i).sm.(v—7nv+c'mv—^').  22 


Formula 
for  Ihe 
determiii 
ation  of 
t. 


[5220] 


*  (2916)  The  values  of  C['^\  C['^\  CJ,^»^  deduced  from  [5114— 5116],  agree 
^^^  very  nearly  with  those  given  by  the  author  in  [5217 — 5219]. 

I  (2917)  Substituting,  in  [5095],  the  values  of  e',  7  [5117],  e  [5194],  and  those 
[5220a]     of     C»',     Cf\     he.  [5195—5219]  ;  also     ^,     [5221],  we  get  [5220]. 


VII.  i.  ^5<  16.]  EQUATION  BETWEEN  t  AND  i-.  541 

The  two  last  terms  were  determined  by  supposing      -  =   -tttz-  •        This     [^2'ii] 
fraction  depends  on  the  parallaxes  of  the  sun  and  moon;  it  differs  hut  very 

•J  *  ■'  I     •  •    I        7  Sun's 

little  from     -^\-^  ;     hut,  for  greater  generality,  ive  have  connected  it  with  the    p"!!""- 
indeterminate  coefficient     1  +/  ;     and,  by  comparing  the  term  depending  on 
sin.  (r — mv),     with  the  result  of  observation,  we  shall  hereafter  determine  the 
sola  r  para  llax  [5589]. 


[.5222] 


[5223] 
[5224] 


[5223o] 


It  is  evident,  by  what  has  been  said,  that  the  perturbations  of  the  earth's 
orbit,  by  the  moon,  introduce  in  A[^'^,  the  quantity  0,25044.tA  ;*  and, 
therefore,  in  C{'°\  the  quantity  — 0,54139.1^;  whence  arises,  in  the 
expression  of  the  moon's  apparent  longitude,  the  inequality,! 

«  (-2918)     Using  the  value  of    m^     [5082^'],  we  find,  that  the  coefEcient  of    Jl\^'\ 
in   [5015],  is  1      (1      rn)3      M2.(36+21m-15mg)  . 

^  '  4(1— »7l)  ' 

and,  the  term  depending  on     (ji,     is 

-2m^.f..  [  |(l+2e2+2e'^)+;^^^^.(l+fe3+2e'2)  |  .  [5223fc] 

Dividing  this  last  expression   by  the  preceding,  and  changing  its  sign,  we  get  the  term  of 
^'/"',  depending  upon  (x.     Substituting  the  values  of  ?«,     e',     e    [5117,5194],  it  becomes    rsooQ  n 
0,25044. (A,    as  in  [5223]  ;     /x  being  the  ratio  of  the  moon's  mass,  to  the  sum  of  the  masses 
of  the  moon  and  earth  [4948']. 

t  (2919)     Tlie  symbol     fi.     is  introduced   into  the    expression    of    C','^'    [5115],   by 
means  of  the  value  of    A[^~\      Now,  the  coefficient  of    .4^''^    in  [5115],  is 

4(1 — my  1 — m  1 — m 

and,if  we  use  the  values  of  ?«,     y,     e,     .5^°'     [51 17,  5194,  5157],  it  becomes    —2,1326. 

Multiplying  this  by  0,25044.fj.  [5223],  we  get  — 0,534.(/.,  instead  of  — 0,54139.|(a  [5224]. 

This  part  of     C,'""-"  produces,  in  the  expression  of   7it-\-s    [5095  line  20,  or  5220  line  21], 

the  terra  r>  co/i        "      ■     /  \  [522561 

— 0,534 .  fj^ .  -  .  sm.  [V — mv)  ;  \_o<.^oui 

and,  by  changing  its  sign,  we  get  the  corresponding  term  of  the  moon's  longitude   v  [5225]. 

The    inequality   of  the  earth's  motion,    depending    on    the  direct    action    of  the    moon    [5225c] 

[4314,  43166],  using  the  same  symbols  as  in  this  article,  is 

fA.-,  .  sin.  (v  —  mv)     [5225'],  nearly  ;  [5225rf] 

as  is  evident  by  comparing  the  notation  [4313]  with  that  in  [4757,  Sic.].     The  ratio  of  the 
two  inequahties  [5225,  5225']  is  as  in  [5226]. 
vol..  III.  136 


642  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[5225] 


a 


0,54139  ./^ .  -, .  sin.  (v—mv). 


a 


icUoTof     The  direct  action  of  the  moon  upon  the  earth  produces,  in  the  motion  of  the 
earth,  the  inequality, 


[5225']  f^  •  -,  •  sin.  (v  —  mv)  ; 


this  action  is,  therefore,  reflected  to  the  moon,  hy  means  of  the  sun,  but  decreased 
[5226]     in  the  ratio  of    0,54139     to  unity. 

The  preceding  expression  of     nt-\-i,     contains  the  coefficients    c   and  g, 
[5237]     which  depend  on  the  sun's  action.     We  have  given  their  analytical  values  in 
[4986,  5228a:],  and,  by  reducing  them  to  numbers,  we  have,* 

[5228]  c  =  0,991567; 

[5229]  g  =   1,0040105. 


*  (2920)     Dividing  the  coefficient  of    cos.(n)— ra)     [4961  lines  3— 7],  by i — -, 

we  "et    ^+</s'^     [4975],  as  in  the  following  expression,  using  the  value  of  m^    [5082^']; 

24-c2^3e'2_2(B«'4-Bra).ll^_(l_^2„j_e).^(2).(]_5e'a^ 


m 


[5228a]    p-\-qc' 


, ...    ;  -4  [  i+2»+(4.r^'^-i).(^:-+^y  ] .  ^r>. (1-f.-)  I 


'"^''^  '-y^.Kl+6m+c).(l— «)+7+(2— 2m— e)2},^(').(|_|e'2)l 


[52286]  We  have  seen,  in  [4976o,  h\,  that  the  quantities  Âi\  Ap,  Bf\  B'„:\  £«>  contain 
implicitly   the   factor     1 — Je'-  ;     whicli    must  be    particularly   noticed    when  finding  the 

[5228c]  values  of  f,  q,  from  [5228a].  Thus,  if  we  neglect  terms  of  the  sixth  order  in  the 
equation  [4998],  we  shall  find,  that  the  term  [4998  line  1]  may  be  put  under  the  form 

[5228d]  f  »'•  ^{l  +  (H-2«0.c^+i7^|.(l-fe'^). 

The  factor     1— |e'-     is  equal  to     0,99929322     [5117];     and,   if  we  put,  for  brevity, 
[5228e]     -  =  0,99929322,     we  shall  have      1  =  lc.{\ — 4e"~).      Hence  it  is  evident,  that,  if  we 

ft 

have   found,  by  a  previous  computation,  the   numerical  value   of  the  first  line  of  [4998], 
[5228/]    which  we  shall  represent  by     A^,    we  can  put  it  under  the  form     A^Tc  .  (1 — |e'^)  ;     and, 


VII.  i.^  16.] 


EQUATION  BETWEEN  /  AND  v. 


543 


The  motion     (\—c).v     of  the  lunar  perigee  [4817]  is,  therefore,  by  the 
preceding    theory,   equal    to     0,008433. w     [5228].       This  motion    is,     by 


[5230] 


[5228A] 

[5228i] 
[5228ft] 
[5228/] 
15228m] 


by  this  means,  it  is  reduced,  by  a  very  simple  method,  to  the  form     —p — qc'^,     adopted 

in  [4975].     In  Hke  manner,  the  second  line  of  [4998],  which  may  be  represented  by    A^, 

can  be  put  under  the  form     A,k.{l—U'-).     The  term     Bf,     which  occurs  in  the  third 

line    of  [4998],   can   be   put  under   the   form     Bi'''A'.(l— |e'~)  ;     as   is  evident,  from  the    [5228g-] 

inspection  of  the    formula  [50G-2],  neglecting   the  small  terms,  similar  to  those  omitted  in 

[5228c].     Lastly,  the  term     B':!\     which   occurs   in   the   third    line   of  [4998],  is  nearly 

equal    to     — 0,000002     [5177]  ;    and,  as  this  is  so  very  small,  we   may  put    it    equal  to 

B^''>k.{l — 2f'^)-      Hence    it    appears,    that,    if  the  analytical  value  of    Af^    be  deduced 

from  [4998],  the  terms  depending  on     e'-,     will  appear  very  nearly  under  the  form  of  the 

factor     (1— |e'^);     so  that  we  may  deduce,  from  the  numerical  value   of    ^i,"'     [5157], 

the  term  depending  on     e'^,     by  changing     A^^    into     A'-°^k.{l — ^e'").       Proceeding  in 

the  same  manner  with  [4999],  we  find,  that  the  terms  depending  on    e'^  may  be  obtained, 

by  changing    ^i"'  into     ./?,"it.(l  — |e'^),     and  using  the  numerical  value  of   ^['''  [5158]. 

In  the  equation  [5000],  from  which     «/Z,'-'     is  deduced,  the  terms  depending  on     e'-     are 

omitted,   on    account    of  their  smallness.      But,  if  we   inspect    the  functions  which    are 

enumerated  in  [4961(Z,  c],  and  used  in  the  formation  of  the   equations  [4999,5000],  we 

shall  see,  by  noticing  the  terms  depending  on     e'~,     that  the  chief  terms  of    •/1[^'',      •^f\ 

are  formed  in  the  same  manner,  with  the  factor     1 — Je'^,  as  in  [4879A',  4879/line  1]  and 

[4876e  lines  2,3,  Sic.].     Hence,  it  is  evident,  that  we  may  proceed  with    Af'   as  we  have 

with     .4','>     [522S/r],  and  put     Jli' =  Afk.(l—le'-).     The  terms  of  e' 2,    which  occur 

in  the  values  of     B'f\     B?'     [5064,  5065],   produce   not  much  efiect  in  the  computation 

of    i^e'-,     or     iqE'^,     in   the  value   of    c     [4986]  ;    so   that   we   may,   without    any 

sensible  error,    change     B'f     into     Bf'k.{l  —  ie'^),     and     jB«^     into     Bf A.(l— fe'^), 

as  the  author  has  done.     Hence,  it  appears,  that  if  we  neglect  terms  of  the  order     e'*,  we 

shall  obtain  very  nearly  the  terms  depending  on     e'^,     in  the  second  member  of  [5228a], 

by  substituting 

A^\(l—^e'^)=^fk.{l-5c'^)  ;  ^;'\(1— |c'2)  =:^',»7c.(l— 5c'2)  ; 

^f  .(1  -Je'2)  =^«>t.(l— 5c'2)  ;     B'i'  =  27,->A-.(  I— fe'2)  ;     5f  =  Bf'>k.{\—^e'^)  ■ 

and  then  putting  the  terms  independent  of  c'^  equal  to  p,  and  the  rest  equal  to  qe"^. 
Having  thus  obtained  the  analytical  expressions  of  p,  «7,  we  must  substitute  in  them  the 
values  of    A° ,    A^\    he.  [5157 — 5179J,  and  we  shall  obtain  very  nearly, 

p=:  0,01678 1;  9  =  0,04973. 

Substituting  these  values,  and  E'  =  c':=  0,01 6814  [5117],  in  the  expression  of  c  [4986], 
it  becomes  very  nearly  as  in  [5228].     From  this  we  obtain  the  expression  of  the  motion  of 


[5228n] 


[5228o] 

[5228;>] 

[52289] 

[5228r] 


544  THEORY  OF  THE  MOON  ;                                 [Méc.  Cél. 

fJa'peri-*^  obscrvation,  cqud  to     0,008452.î;     [5117  line  2];     which  differs  from  the 

gee. 

[5231]  preceding  hut  by  its  four  hundred  and  forty-fifth  part. 


[5231'] 


The  motion  of  the  perigee  is  subjected  to  a  secular  equation,  whose 
analytical  expression  is  given  in  [4982,  &c.].  Reducing  it  to  numbers,  it 
becomes,* 


[5228r']     the  perigee     (1 — c).v     [4817,5228],  as  in  [5230]  ;  which    agrees  very  nearly  with  that 
deduced  from  observation    0,00S45199.d  [51 17  line  2]. 

[5228«]  The    coefficient  of    y.sin.  (g-u — Ù),    in  [5019]   is  put  equal  to    y+î"fc'^     [5053]; 

hence  we  get,  by  using  [5082A'], 

\-\-2e^—ly^-\-%e'"~  ^ 

-I  I  '^^"-^^;-'g+"\z?f>+4^^°)^  .(l-le'^) 


[5238f]  p"^_y"e'2  =  |m' 


a 


[5928t/] 


Substituting  the  values  of    Bf%.(l — Je'-),     &:c.   [5228o-,o];  and  then  putting  the  terms 
which  are  independent  of    e'^     equal  to    p",     and  the  rest  equal  to     q''e'^;     we  shall 
get  the  analytical  expressions  of    p",     q".     Reducing  these  values  to  numbers,  by  means 
of  [5157—5186]  we  get,  very  nearly, 
[5228t)]  p"  =  0,0080337;  ç"^  0,0123967. 

These  values  and  that  of  E'  [5228)],  are  to  be  used  in  finding  the  retrograde  motion  of  the 
nodes  [5059],  which  becomes,  by  retaining  only  the  terms  depending  on  the  first  power  of  v  , 

[5228H  |^/(l+y')_l+  _|_,^.£'a|  .,. 

Putting  this  equal  to  the  expression     {g — l).v,     which  is  assumed  in  [4817]    we  get, 
[5228.]  ^,  =  ^(l+p'')+J^,^    ; 

and,  by  substituting  the  values  of    p",     q",     E'     [5228f,r],  we  obtain    g    [52i29]. 

*  (2921)     The  secular  motion  of  the   perigee  depends   upon   the   term     \q' .fe'^.ilv 

[5232a]     [4982]  ;  which  may  be  put  under  the  form     iq'-fu''i^'^ — E'^).dv    [5095c — </];  supposing 

the  integral  to  commence  at  the  epoch  where     e'^E'.      Using  the  value  of    q'     [4979], 

[52325]     and  multiplying  by     g^,     it    becomes,     L  ^  J  Vf  ?ft^./(,"(fi'^— E'^)^  Substituting, 

in  the  factor  between  the  braces,  the  values  of    p,     q,     m    [5228y,  5117],  we  obtain  very 
nearly  the   same  expression  as  in  [5232].     The  secular  motion  of  the  moon's  longitude  is 
[5232c]     _3„j2y^^(f'2_£'3)_j„     [5089a,  5232a],  corresponding  to  [5232']. 


Vll.i.  .^16.]                            EQUATION  BETWEEN  t  AND  v.  546 

0^  =  3,00D524.m~.f(e'-—E'-).dv.  [5232] 

It   has  a  conlrari/  sig7i  to  the  secular  equation  of  the  mean  motion  [523?c],  [5232'] 
and  is  nearly  three  times  as  great. 

The  retrograde  motion  of  the  node  of  the  moonh  orbit,  (g — l).v  [4817],  is, 

by  the  preceding  theory,  0,00401 05. v  [5229].     This  motion  is,  by  observation,  [^233] 

equal  to  0,004021 75.?;  [5117  line  3],  Avhich  does  not  differ  from  the  preceding,  ^'^'^,';^»'^  ^ 

by  its  tliree  hundred  and  fiftieth  part.  hm^'ù'Â.' 


pertgre 
iitli]  ilniif. 


This  motion  of  the  node  is  subjected  to  a  secular  equation,  whose  analytical 
expression  is  given  in  [5059].     Reducing  it  to  numbers  it  becomes,* 

6ù=  0,735A524.m-.f(e'^—E"').dv.  [5234] 

Jt  has  a  contrary  sign  to  that  of  the  moon'' s  mean  longitude  [5232c].  Hence  it 
folloics,that  the  motions  of  the  nodes  and  perigee  are  retarded, whilst  the  moon''s 
mean  motion  is  accelerated  ;  and  the  secular  equations  of  these  three  motions 
are  always  in  the  ratio  of  the  numbers  3,00052,  0,73542  and  1  [5235] 
[5232,5234,5232c].  Therefore,  in  the  preceding  expression  of  nt-\-s,  we 
must  substitute,  for  the  angles     cv,    gv,     the  following  quantities  ;t 


« 


(2922)     The  secular  motion  of  the  node  depends  upon  the  term, 


^-./e'^.rf.     [50565];  t^233a] 


[5233i] 


which  may  be  changed,  as  in  the  preceding  note,  to 

Substituting,  in  the  first  factor,  the  values  of    p",     q"     [5228;;],  it  becomes  very  nearly 
as  in  [52.34]. 

t  (2923)     The  motions  of  the  perigee  and  node     (1 — c).v,     (g — \).v    [4817],  ai'e     l5'>3ea^ 
changed,  by  means  of    the  secular  equations,  into 

(1— c).i.-i-.3,(]00J2.f/ft2./^'(e'2_JS'2).f/y     [5232], 

{g-l).v+0,-35A524nv'f,'{e'^—E'^).dv     [5234],  ^^^^^''^ 

respectively.     This  requires,  that  we  should  change     cv     Into 

CT_3,0C052.|<7i2./^''(e'2_£'2).c/f,     as  in   [5236]  ; 

and,     go     into  [523flf] 

^»+0,735452.|m2./o'(e'2— i;'2).(/r,     as  in   [5237] . 

VOL.  III.  137 


546  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5236]  cv— 3,00052  4.mKf(e''~—E"').dv  ; 

[5237]  gv+0,13ôiô24.m\f(e'-—E'^).dv . 

Hence,  the  secular  equation  of  the  mean  anomuhj  is,* 
[5238]  — 4,00052.|.m-./(e'~— £'-).^v  ; 

or,  nearly  four  times  that  of  the  mean  motion. 

17.   We  shall  now  pi-oceed  to  determine  some  oj  the  most  sensible  inequalities 
of  the  fourth  order.     One   of   these  inequalities    depends  upon  the   angle 

2d 2mv — 2gvArCV^2(: — ^,  and  we  have  determined,  in  [4904  line  17,  5014], 

the  part  of  ahu,  which  depends  on  the  cosine  of  this  angle.    Then  we  find,  by 
^15,  that  the  expression  of  nt-\-i,   contains  the  inequality,! 

( 3nt'-^.(2-|-w)      2^*'^'+3^*'^^  > 

{       s.(2o— 2+2w) '_ [ L.e>^sin.(2i;— 2mi;— 2u-r+ci)+2d— ^). 

2 — 2m — 2g-\-c 

This  inequality,  reduced  to  numbers,  is 

8%67.sin.(2i; — 2mv — 2gv-\-cv-{-2è — n). 
We  shall  now  consider  the  inequality,  relative  to  the  angle  {2cv ^2v-2mv-2zi). 
If  we  connect   all    the    terms,   depending  on   the  cosine  of  this  angle,   in 


Invest  iga 
lion  of 
some 
lor  m  s 
of  tUo 
fourth 
order. 


[5239] 


[5240] 


[5238a] 


*  (2924)    Subtracting  the  secular  equation  of  the  perigee  [5232],  from  tliat  of  the  mean 
motion   [5232c],  we  get  the  secular  equation  of  the  mean  anomaly,  as  in  [523S]. 

+  (2925)     The  part  of  dt,  which  would  correspond  to  the  term  of  nt-\-s  [5239],  may  be 

1         a~ 
deduced  from  it  by  taking  the  differential,  and  multiplying  by    -  =-^  [5092c], by  which 

means  it  becomes 

,.o^„  T  \  _  J!f^±]!!l 2^f'«4-  3  ^<;'^  I  .  "4^"  .  ey\ co^.[2v—2mv-2gv-\-cv). 

[o239a]  ;^        8.(2g-— 2+2m)  '      '  '      ^       V^a,  ^  ù   "T     ; 

r"239tl     Now  the  three  terms  of  this  function  are  contained  in  the  expression  oi  dt  [509ap],  as  we 

shall  see,  by  the  following  examination.    The^)-s<  term,  between  the  braces,  — -  '"  _^XV- 

[5239a],  occurs  in  the  table  [5O90è]  ;  by  multiplying  the  term — 2e.  cos.cj;  in  its  first 
column,  by  that  of  [50S2s  line  13]  in  its  second  column.     The  second  term  — 2A\^^\  arises 

[5239c]  ^^.^1^^  [5090^  line  1,  4904  line  17].  The  third  term  S^''^'  is  deduced  from  the  table 
[5090O-].  It  corresponds  to  — 2A\^^^y-.co5.{2gv—2v-\-2mv)  in  its  first  column,  or  in 
[4904  line  14];  and  to    — Se.cos.c»     in  the  second  column.     Substituting  in  [52-39]  the 

t^^^''^    values  of   m,  g,  c,  y  [5117],  e  [5194],  and  ^.">,  .3/«  [5169,5172],  we  get  [5240]. 


Vll.i.§n.]  TERMS  OF  THE  FOURTH  ORDER.  647 

the  development    of  the    equation    [4754 J,    which  we    have   made  in  ^  6, 
this  equation  becomes,  by  noticing  only  these  terms,* 

_  a 
dfJii  ,3m       (10 — 19  m  4-8  m^)  .  ('2 — m-i-c)      „  ^^      ,  r.        r»  o   \        r-^.,-, 

0  = l-u  +■ —  .  -!^ P^ —i ^^- .e-.cos.(2cv-ir2v — 2mj;— 2^):      [5241 

dv-^^     ^2fl,  4.(c+l-m)  ^       ^  ^' 

therefore,  by  putting  ^'^'''.e-.cos.(2ci'+2iJ— 2hw' — 2a),   for  the  corresponding      [5242] 
term  of     «'«     [4904],  we  shall  have,! 

|m-.  (10— 19m+8m2) .  (2— m+c) 

/J'C)  —    -^  '' 1 ^^ 1_.  r'>24Hl 

^2  4.(c+l— m).{4.(c+l— ?«)— M 

Then,   if  we  put     C"^'".e-.sin.(2cz;+2?; — 2inv — 23),     for   the   corresponding      [5244] 
term  of  the  expression  of    nt-{-:,     we  shall  find,  by  §15,t 


*  (2926)     The  terms  depending  on  the  angle  2cv-\-2v — 2mv,'m  the  equation  [4961], 

are  included  in  the  functions  which  are  enumerated  in  [4960e],  and  if  we  divide  these  terms 

3»t2  [5241a] 

by  the  common  factor  -^  .e2.cos.(2ci'-|-2L' — 2mv);  we  shall  obtain  in  [4S701inel2]  the  term 

I  (G-1 5m+8m^);  and  in  [4879  line  8]  the  term  ^(4-4ffi)  nearly.  The  sum  of  these  two  expressions 

Is    1(10— 19m+Sm2)';     addingthisto    ^(10— lOm+Sm^).— ^ [4892  line    11],     we 

obtain  i(10-19m-|-8m^).~-T-- .  Connecting  this  with  the  two  first  terms  of  [4754]    —^+u,     [524lcl 

according  to  the  directions  in    [4960c,  Sic.],  we  get  [5241]. 

t  (2927)  Integrating  the  equation  [5241],  by  the  method  in  [4998a— c],  we  find,  that  if 
-.cos.(?y+|3)     represent  any  term   of   [5241],  the  corresponding  term  of    «m     or     a5u    rgoio  i 
[4998c,  a]  will  become, 

In  the  present  case,  we  have, 

i  _  o  (c+l-ni)  ■  ?=  ^  ^IfL     (10-19m+8,ng).(2-m+c) 

~^  ^'  a,       '^'     a,      '  4(c+l— j«)  [5242c] 

Substituting  these  in    [52426],    and  putting  the  result  equal  to  the  assumed  expression 
[5242],  we  get,  by  using     nr    [5082A'],  the  value  of    .4'^°'     [5243]. 

X  (2928)     If    nt-\-i     contain  a  term  of  the   form    [5244],  its  differential  will  give,  in 
nii,    the  expression 

ndt  =  {2c-{-2—2m).C'<-^h'^.cos.(2cv-}-2v—2mv).dv.  [5245a] 


648  THEORY  OF  THE  MOON;  [Méc.  CVl. 

(10— 19/n+8m2)        3m^.{\—m)  9m^ 


[5245c] 


—%m-. 


8.(c+l— m)  2—2m-\-c  16.(1— ffl) 

[5245]  ^,(0,     _      (— 2yl'f+34°'— 34°' 


2c-{-2—2m 
Reducing  the  formulas  [5243,5245]  to  numbers,  we  get, 

[5246]  ^'f")  =     0,00201041  ; 

[5247]  C'f  =—0,0130618; 

hence  we  obtain,  in     nt-\-s,     the  following  inequality, 

[5248]  —  8%ll.sin.(2c«;+2t;— 2wt;— 2^)   [5244] 


Multiplying  this  by    -  =  [5092c],  we  shall  get,  in    dt,     the  term, 

[52456^  dt  =  (2c+2-2m).C'l%^-^.cos.{2cv-\-2v-2mv). 

Comparing  tliis  with  the  terms  of  the  functions  [5090^],  depending  on  the  angle 
2cv-^2v — 2mv,  we  shall  get,  for  (2c-\-2 — 2m)  .  C'^'',  tlie  terms  of  the  numerator  of 
[5245]  ;  namely, 


,    ,  (10— 19m+8m2)        3m^.{l—m)  9»/2 

^      '     8.(c-|-l— 7«)  2— 2m+c  16.(1 -m) 

—2AT^3Ai'^—3Af^  ;  2 


as  will   appear  by  the  following  examination  of  the    functions  [5090j3],   divided    by   the 
common  factor 
[5245d]  ^^'~i — •cos.(2cu+2d — 2mv). 

The    function   [5082s  line  10]  contains  a  term,  depending  on  the  angle     2cv — 2f-j-2m», 
deduced    from    [4885  line  10]  ;     and,    we    find   in    [4885 line  11],    a    similar    expression 

[5245e]     —  |m^. — gTTT3'"T — '  >    corresponding  to  the  first  term  of  [5245c].     The  term  neglected, 

in  r5090Mine71,  produces  the  second  term  of  r5215rl,     —    -^ ;       and,    that  in 

"^  -"  2— 2m-[-c 

[5090&line  12],  is     —  TTr-rj^'     as  in  the  third  term  of  [5245c].     The   term  of    ai)u 

[5242]  produces,  in  [5030p  line  2],  the  term  —2^'™  [5245c line  2].  The  term 
[5245/]    jjgg^g^jgj   ;^    [.5090^  line  16],    gives      .3./2/2)     [.V24.5c  hne  2].       The    term     —  S^!,») 

[5090^  line  9],  is  the  same  as  in  [5045fline2].  Now,  substituting  in  [5243,  5245],  the 
[5245g-]    values  1-5117,5194,5157,5159],  we  get  [5246,5247].      Lastly,  we  get,  from  [5214],  the 

expression  [5248],  by  using  the  values  [5247,  5194]. 


VII.i§17.]  TERMS  OF  THE  FOURTH  ORDER.  649 

The  expression  of     dt     ^  1 5,  gives  in     ni+f,     the  term,* 
QA'-^Kee'.  sin.  (2v — 2mv-\-cv — c'mv — a+ra') 


2 — 3/rt+c 


[524'.»] 


This  term  is  sensible,  on  account  of  the  magnitude  of  the  factor  A'-^'^  [5161]  ;     [52491 

it  is,  therefore,  useful  to  consider  the  inequality  relative  to   the  argument 

2v — 2.mv-\-cc — c'mv — ^-\-ui'.      The  equation  [4754]   gives,  by  noticing  only 

the  terms  we  have  developed  in  §  6,t 

2 
dda  ,           m    21.(2— 3m) -(4—3»!  + c)        ,  .^        ^ 

0  =.—  +»—  -•         4.(2_3;„^,) ■  ^^  •  cos.(2v—2mv-^cv-c'mv—v.+..').      [5250] 

We  shall  put 

^'*''.ee'.cos.(2i' — 2mv-{-cv — c'mv — to-j-tb')  [.5251  ] 

for  the  part  of    a'u    depending  on  the  argument  in  question  ;  we  shall  have. 


*  (2929)     This  term  is  omitted  in  the  product  of  the  two  quantities  in  [5090^1ine  20]  ; 
but,  it  is  introduced  in  this  place  on   account  of  the  magnitude  of    Jl^'^'>     [5161,5249'].     rEQ4n 
Having  noticed  this  i)art  of  the  expression,  it  becomes  convenient  to  introduce  the  smaller 
quantities,  depending  on  the  same  angle,  as  in  [5250 — 52-57]. 

t    (2930)      The    equation    [5250]   is    obtained    in  the   same   manner  as    [5241],   by 
dividing  the   terms  of  [4960e],  depending  upon    the  angle    2v — 2mv-^cv — c'mv,     by  the 

common  factor,  — " 

—  ^.— .ce'.cos.(2î) — 2mv~\-cv — c'mv)  ;  [5250«1 

"■/ 

and  connecting  the  resulting  quotients  in  the  following  manner.     The  term  in  [4870 line  7], 
gives     J(l — 2m);     in  [4879 line  4],     i  ;     their  sum    is     2 — 3m;     adding    this   to    the 

rionni-       -^        2(2-3».)  ,      . 

term     4892  hne  /  ,    - — - — ; — ,     we  obtam, 
2~Sm-\-c 

(2— 3m)  .  I  1  +  ^^,-V-  1  =  (2-3m)  j±=^!l±îl,  [52506 j 

Connecting  this  with  the  common  factor  [5250o],  and  adding  the  two  terms  [5241c],  we 
get  the  equation  [5250]  ;    in   which  we  have  corrected  a  typographical   mistake    in  the 

original,  where     m-     is  written  for     — .     Comparing  this  with  [5242a],  we  get,  [5250c] 

.,  _2  21.(2— 3m).(4-3m+c)  .        ^      ^  ,  ^      ^      , 

H  =  —7)1  .         , ,-,    ,'    ,    ^  ■-'— '.ee';       i  =  2— 2m+c— c'm  =  2— 3«+c,     nearly  ; 
4.(2— 37rt+c)  '  I     '  J   ' 

substituting  these  in     aSu   [5242i],  and  putting  the  result  equal  to  the  assumed  value  of 

this  term  of    aiu     [5251],  we  get     A'l'\     as  in  [5252],  using    m^    [5082ft'J.  [5250rf] 

VOL.    HI  138 


* 

5 


•^50  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5«-2]  ...,  _     -2lm"-.(2-3m).(i-3m+c) 

^2    —  4.(2— 3m+c).»  (2— 3m+c)-—l  I 

Then,  if  we  put 

[5253]  C'i,"ee'.  sin.  (2v — 2mv+cv — c'mv — n-j-ra') 

for  the  part  of    nt-\-i,    relative  to  the  same  argument,  we  shall  find,  by  §  15 

2lm^.(2—3m)    ,        21//i'-  ^  ,„,,     ^  „, 

^,„  _  M2-3m+c)  ^  4.(2-3m)  ^    ^    ^^' 

[5'.i54]  ^.    —  2— 3m+c 

Reducing  these  formulas  to  numbers,  we  find,* 

15255]  J'^')  =—0,0134975; 

[5256]  C'^^  :^     0,0534480; 

which  gives,  in  nt+:-,  the  inequality, 
[5257]  1 0,'l  7.sin.(2i) — 2mv-{-cv — c'mv — ra+^i'). 

*  (2931)     Proceeding  as  in  [5245rt,&c.],  we  find,  that  if    nt-\-g    contain  a  term  of  the 
form   [5253].  it  will  produce,  in  its  differential     ndt,     the  term, 
[5253a]  (2 — 3m-f-c).C'l"fe'.cos.(2i' — 'imv-^-cv — c'mv),     nearly  ; 

and,  by  multiplying  by     -  =  -7-;-      [5092f],  it  will  produce  in     dt,     the  term, 

[52536]  (2 — 3m+^)  •  C"^"ee'-  — ^.cos.  (2f — 2mv-\-cv—  c'mv). 

Comparing  this  with  the  terms  of  the  functions  [5090p],  depending  on  the  same  angle,  we 
shall  get,  for     (2 — 3ot-1-c).C'^'',     the  terms  of  the  numerator  of  [5:251];  namely, 

2h>^^{^-3m)  2hn^  2^'")  +  S/^'^)  • 

l^^^^  4.(2-3m+c)  +  4.(2-3.0  ~        '  -     ' 

as    will    appear    by   the  following   examination  of  the    functions   [5090p].      The    term 

21mS.(2-3m)  , 

[5253rf]    [5082«line8]    is  the   same  as   the   first  term  of  [5253c],       4_^2-3m+cJ~    '  ^^^^^ 

■   ^^"'L_      omitted  in  [50906  line  8],  is  the  same  as  the  second  term  of  [5253c]  ;  the  term 
4.(2- 3m)'  ■- 

[5253c]    ^j.     ^^^^     [5251]  produces,  in   [5090JJ line 2],  the  term     —2A'\'\    [5253c];    lastly,   the 

term  omitted  in  [5090^ line 20]  produces     3^</'     in  [5253f]. 

(2932)     Substituting  the  values  of    c,  m    [5117]     in     [5252],    we  get     [5255],    and 
then,  from     [5254],    we  obtain    [5256].     Substituting  this  value  of    C".V\   and  the  values 
^■'^^^"'^    of  e,    e'  [5117,  5194];    in     [5253]    we  get    [5257]. 


VII.  i.>^M7.]  TERMS  OF  THE  FOURTH  ORDER.  551 

It  would  seem,  that  the  inequalities  depending  on  the  angles 

2cv — 2v-\-2mv±c'mv — 2^^^'  [5257] 

ought  to  be  sensible,  on  account  of  the  great  divisors  which  they  acquire  hy 
integration;  it  is  therefore  important  to  ascertain  them  carefully.    By  following     [5257"] 
the  analysis  before  explained,  noticing  only  quantities  of  the  fourth  order,  and 
representing  the  corresponding  part  of     aiu,    by 

^  ^  [5258] 

+A'^^^ey.cos.(2cv—2v+2mv—c'mv—2-.+^/); 
we  shall  find,  that  the  differential  equation  will  become,* 


*  (-2933)     We  shall  put,  for  brevity, 

S  =  2cv—2v+-2mv+c'mv—2zi—zy';         D  =  2cv—2v-i-2mv—c'mv—2vi-\-a';  [5259a] 

and  the  assumed  value  of    aou     [5258]  will  become, 

aou  ==  ^' e)  e\'.cos.S+d'f1  e^c'.cos.B.  f  ^^^^*J 

The  terms  of  the  equation  [49G1],  depending  upon  the  angles  »S',  D,  maybe  found 
in  the  functions  which  are  enumerated  in  [4960c];  and,  to  obtain  all  tlie  terms,  we  must 
review  the  whole  calculation  [4835 — 4961],  in  order  to  notice  the  quantities  which  have 
the  factor  e-e'.  This  great  degree  of  accuracy  is  however  unnecessary,  on  account  of  the 
smallness  of  the  coefficients  in  [5259],  which  are  of  the  fourth  and  higher  orders;  we 
shall,  therefore,  only  notice  the  most  important  terms  which  are  given  by  the  author  in 
[5259].  The  6rst  of  the  functions  [4960e],  which  is  noticed  by  him,  is  that  in  [4870].  [5259/1 
We  may  deduce  this  selected  part  of  the  factor  of  e-c',  from  that  of  e^  [48701ine  II], 
upon  similar  principles  to  those  which  are  used  in  developing  a  function  of  e,  e',  by  Taylor's 
theorem,  by  which  the  coefficient  of  e-e',  may  be  derived  from  that  of  e^,  &c.  If  we  use 
the  value  of  m     [4865],     and  put,  for  brevity, 

M  =  '£-.i6+l5:n+S,n^)  .^  =  l.."^f  .(C+15.+8™=).e^  ^5^59^] 

we  shall  find,  that  the  term  of  e^  [4870  line  11]  is  represented  by 

J\'l.cos.{2cv — 2v-\-2mv).  r5259/"l 

As  this  quantity  does  not  contain  e',  it  is  evident,  that  it  can  be  derived  from  the  first 
member  of    [4870]      -^j^  .cos.{2v—2v'),     by  substituting  the  values    of    /(,   u,    u',    v'     J5259  ] 

[4325,4826,4837,4838]  ;  then,  neglecting  the  terms  depending  on  c',  and  retaining  only  those 
connected  with  e^.  Now,  by  using  merely  the  first  terms  of  [4837,4838],  and  those 
depending  on  the  first  power  of  e',  we  have, 


552                                              THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

/  7(2+llm-f-8m2)_7(  10+19m+8ma)  \  1 

^      ddu  .          3m     )            Ï6                ¥.(2^=2+3H"(     3,  ,00.01'        o        '^ 

[5259]                                            V.        2c-2  +  3m       ^      '                  }  2 

/(10+19m+8HiS)      (9-|-llm-|-8m2)  \  -3 

3  m'     )    8.(2c— 2+  in)  lie  ( 

H .<  >.e-e'.cos(2c'ii-2v+2mv-c'??n'-2ra+î3'); 

V        2c  — 2  +  m        "       ■                   ;  4 


r'  =  ?OT+2e'.  sin.c'^nt';  m' =-.  I  l+c'.cos.c'?;i('|. 

I  Oi^Ofil  I  (X 

If  we  retain  these  terms  of  e',  informing  the  function  [5259/"],  it  will  change  — —  [5259f] 

rrnrrv-i      '"1°     — -r-.(  1+3  c'.cos.c'mii) ,    and  2mw  into   2/«D-4-4e'.sin.c'm-y.    By  this  means  the  function 
[52591 J  u  3  '  -^ 

[5259/],  will  be  increased  by  the  terms, 

r5''59A-l  M.(3e'.cos.c'm«).cos.(2c!; — 2v-\-2mv) — M.{4e' .sin.c'mv).s]n.{2cv — ^v-j-'^mv)  ; 

the  second  of  these  quantities  being  obtained  by  means  of  [61]  Int.  by  putting 

z  =  2cv — 2«-j-2?/u',         a=  4c'.3in.  t'mw  [5259i]. 

Reducing  the  terms  of  [5259^'],  by  means  of  [17,20]  Int.  we  get,  by  using  the  abridged 
symbols   [5259a], 
r5259ml  .M.(3e'.cos.c'mi;).cos.(2c« — 2v-\-2mv)  =  #ilie'.cos.S-[-M/ft'.cos.X); 

— ■M.(le'.sin.c'mv).sin.(2ci-— 2D+2mi')  =  2;He'.cos.S— 2.1'ie'.cos.I>. 
[o259)iJ  '         ^  ' 

Tiie   sum  of  these    two  expressions  gives   the  value  of  the   function  [5259/i]  ;    and,  by 
re-substituting  the  value  of    M  [5259e],  it  becomes, 

2 

[52590]  iMt'.  cos.S—lMe'.cos.D=  ^.{6+l5m+8m^).e'>e'.\^^.cos.S- ^^.cos.D]. 

A  similar  expression  is  obtained  from  the  terms  in    [4S79  line  7],  putting     c^l,    and 

2 

[5259/)]     M=:  —  ^— .  (l+77j).c-.     Substituting   this   value  of    iVi,  in  the   first   number  of  [5259o], 
we  get  the  terms, 

1  2 

[5259?]  -ï-(l+'«)-cV.^|  .cos.S— è.cos.I>|=^.(— 4-4m).cV.  ItV-cos.à— tV-cos.!)}. 

Adding  together  the  terms  in  the  second  members  of  [5259o.9],  we  get 

2 

which  are  the  same  as  the  first  term,  connected  with  S  [5259  line  1]  ;  and  the  second  term, 
[5259i]     connected  with    D,    in  [5259  line  3j. 


VII.  i.^  17.]  TERMS  OF  THE  FOURTH  ORDER.  ÔÔS 

therefore,  we  shall  have,  [5259"] 

We  may  proceed  in  a  somewhat  similar  manner  with  the  term  in  [4892  hne  10],  taking  in 
the  first    place  its  differential,   so   as   to  make  it  of  a  like  form  ;    and,  after  reducing   the  "* 

products,  which  introduce  the  angles  S,  D,  again  integrating,  to  correspond  to  the  integral     [5259i] 
in  the  first  member  of  [4892].     Now,  if  we  put 

2 

iVi=^(10  +  19ra+8m2).e^  [5259<] 

the  differential  of  [4892  line  10]  becomes, 

Mdv.sin.{2cv—2v+2mv)  =  Mdv. cos.  {2cv — 2v-\-2mv — 90'').  [h25Qu] 

The  second   of  these  expressions  may  be  derived  from  [5259/],  by  decreasing  the  angle 
2cv—2v-\-2mv     by     90";     which  requires  that     S,     B     [5259a]    should    be  changed    r5259„r| 
into    S — 90'',     D — 90",     respectively,  and  then  multiplying  by     ih.      The  same  changes 
being  made  in  the  resulting  correction,  in  the  first  member  of  [5259o],  we  obtain, 

iMe'.  c?i).cos.(S— 90'')— JJI/e'.  dv.cos.  {B—W)  =  JJlic'.  dv.sm.S—lMe' .  dv.sin.B.         [52591.] 

Now,  integrating  this  second  expression,  according  to  the  directions  in  [5259;],  we  get 
the  additional  terms  of  [4892],  as  in  the  first  member  of  the  following  equation,  and,  by 
re-substituting  the  value  of    M    [5259^'],  we  get  its  second  member. 


7Me'  Mc' 

.cos. o  4"  5~K n  I      .  cos.B 


[5259«i] 


2.(2c— 2+.3m)  '    2.(2c-2+m) 

=  |^.(10+l9.  +  8.^).eV.  J-^_|^.cos.S+^-i^.cos.i)^. 

The  terms  of  this  last  expression  are  the  same  as  the  second  term  connected  with    S 
[5259 line  1],  and  the  first  term  connected  with     B,    in  [52591ine3]. 

The  next  terms  of  [5259]  arise  from  the  part  of  the  function  [4934  or  4932/t]  which  is 
included  in  the  table  [493 Ip].     For,  if  we  take,  in  the  first  column  of  this  table,  the  term 
^fee'.cos.icv-^-c'mv)     [4931pline  22], 

and  in  the  second  column,  the  term 

5e      .     , 
—  .sm.  (2î>  —  2mv  —  cv)^ 

which  occurs  also  in  [493 Ij? line  17],  it  produces,  by  the  process  used  in  [493InJ,  the  term 

6m  5  c9  e'  „ 

-  V  ■  2.(2c-2+3m)-^'  •^"^•(^'^''~^"+^'""+"'"^'')  '  [5259x1 

which  is  the  same  as  the  term  depending  on     A^^'>     [5259  line  2J.     In  like  manner,  by 
combining  the  term 

VOL.  III.  139 


[5250J-] 


554  THEORY  OF  THE  MOON  ;  [Mtc.  Cél. 


[5260] 


« 

AT 

— 3m2 

( 

7.(2+1  ]H(+S?«2j 

16 

7.(10+19m+8m2)_ 

-40^i8>f    ' 

1 

1- 

-#«■2- 

-(2c- 

-2+3,nf  S 

2 

8.(2c— 2+3» 

0         ) 

^i'J'ce'.cos. {cv—C7nv)     [493]pline  23], 

with  the  same  term 

5e 
—  —  .sin.  (2«;  —  2mv — cv),     in  [4931^  line  17], 

we  get,  by  the  method  used  in  [4931n],  the  terra, 

2 

Gm  5  e~  e' 

[5259y]  —   —  •  ;^-^H-;^247^-^i*'C0S.(2cîJ — 2v-\-2mv — c'mv),     as  in  [5259  line  4]. 

The  function  [4î;03 line  1]  contains  the  term —.a5u;      and,   by  substituting  the 

value  of    0  (5w     [5259/!/],  we  get, 

[52592]  —  —  .eV.^^'f.cos.5+.^'f.cos.D|,     as  in  [5259 lines  2,4]. 

This  includes  all  the   terms  noticed  by  the  author  in  [5259]  ;    there  are  other  terms, 

2 

having  the  factor     m.m.e~e',     which   he   has    neglected   on  account  of    their  sraallness. 

ddu 
dv^' 


Connecting  these  terms  with     t^  +  w     [5241c],  it  becomes  as  in  [5259]. 


[5260ol         *  (2934)     Taking  separately  into  consideration    the  terms   in   the   two   first  lines  of 
[5259],  which  depend  on  the  angle     S  =2cv—2v+2mv-j^c'mv     [5259o],  they  become 
[52fi0i]     of  the  same  form  as  in  [4990a],  by  putting 


„      „_=     C  7.(2  +  ll'.+8mS)        7.(10+19m+8m^)  5^f^  -^       ^, 

[5260c]      /^=om  .  j -, 872c-2+3«.)  2c-24:3^~^^'     (  "  ^  ^  ^ 

[5260rf] 


16  8.(2c— 2+3m)  2c— 2+3  m 

i  =  2c — 2+2/n+c'nj  =  2c — 2+3w,     nearly. 

The  corresponding  term  of    au,     or     aHu,     is  represented  by    P«.cos.(w+)3)    [4998c]; 
and,  if  we  compare    it  with    the    assumed  form  of  this  term   of    aSu,     in  [5258  line  1], 
rs^COd'l     ^'■'^    ^et  Pa=A'i-'e-e' ;     hence  [4998a]  becomes,  by  multiplying  by  c,  and  substituting 
this  value  of    Pa, 

TT 

[5260e]  U  — (.1      I  ).J1,  e  e-t  ^. 

[5260/"]  Substituting  in  this,  the  value  of  H  [5260c],  rejecting  the  common  factor  cV,  and 
usin"-  m-  [5082A'],  we  get  [5260].  Proceeding  in  the  same  way  with  the  terms 
depending  on  the  angle     D     [5258  line  2,  and  5259  lines  3, 4],  corresponding  to 

rjpgQ  I  z;=2c — 2+2m— c'm  =  2c— 2+OT,    nearly, 

we  easily  obtain  the  value  of    -4'f'     [5261]. 


Vll.i.§17.]  TERMS  OF  THE  FOURTH  ORDER.  655 

3)  _  — 3;»'^  C  (10+19m+8wM0^f)  _  (3+ 1 1  m+8m'-*)  ) 

'     ~  l—inr—{2c—2-\-m)^'  I  8.{2c—2^m)  To  3"  ^'"^^^^^ 

If  we  denote  the  corresponding  part  of     ?;/+-     ^y,* 


*  (2935)     If  we  take  the  differential  of  the  term  of    ni-j-s     [5262  line  1],  depending 

1(1^ 
on    the   ansrle     5'=2cy — 2v-\-2mv-\-c'mv,     and    multiply    it   by     —  =  -— —     r5092cl, 

n  ya^      "■  ■■ 

putting  also     c'=l,     we  get,  in     dt,     the  term, 

dt  =  {2c-2+3m).C'[-^  e^e'.—  .cos.S.  [5261a] 

Substituting   in  this,  the    assumed   value  of     C'f''     [5263],  we  find,  that   the  result  is 
represented  by  the  fimction  [526 1  r],  or  the  numerator  of  the  expression  [5263],  multiplied 

by  the  common  factor  e^e'.  —^ — .cos.S;  and  it  will  appear  by  the  examination  in  [526l/-a?],     rsaciM 

that  the   corresponding  terms  of  the  value  of    dt     [5090p],  neglecting  the  same  factor 
[52616],  agree  exactly  with  this  function  [5261c]  ; 

21m3.(10+19/n+8m^)+120mS.^f 21»i-.  (2-j-3.'rt)  63m2 

16.(2c— 2+3«0  M2^3^^)~W:(2^:^3^)  ^      ^^^^^^^ 

— 2^'f +3^i''— 3./3^«+3.^i«.  j1['\  2 

By  a  similar  process  with  the  term  depending  on  the  angle     D  =  2cv — 2v-\-2mv c'mv 

and  the  assumed  value  of     C"f^     [5264],  we  find,  as  in  [5261/-a;],  that  the  corresponding 

terms  of    dt     [5090p],  neglecting  the  common  factor     c"e'.  — ^  .cos.I?,   are  represented     [5261dl 
by  the  function  [5261e],  corresponding  to  the  numerator  of  [5264]  ; 


—3m^.{l0+l9m-\-8m^)i-l  20m^.^f^         3m^.{2-{-m)  9m^ 

+   ^  /o     ...      „x    + 


16.(2c-2+«0  ■    4.(2-7«-c)  ^  ]6.{2—m) 

—2A'^^^-\-3df'—3Al^'+3A,^\A['K 


[r,26U] 


We  shall  now  proceed  in  the  examination  of  the  functions  [5261c,  c]  in  order  to  prove, 
that  they  agree  with  those  in  [5090^].     The  first  term  of  [5090/?  line  1]  depends  upon  the 
function  [50824],  which,  when   fully  developed,  contains  terms  of  the  required  form,  with     l-'^W] 
the  factor     eV.      The  terms  of  this  function,  which  are  retained  by  the  author,  may  be 
derived,  in  a  very  simple  manner,  from  those  depending  on     e^     [5082s  line  10]  ;  namely, 

^m^i{10+l9m+8m^).  ^—.co5.{2cv-2v+2mv)  ;  ^,,201^] 

by  the  process  used  in  [5259s' — w].     For,  if  we  substitute  in  the  expression  [5261^],  the 
value  of  the  common  factor  g 

|m2  =  |m^.^     [5082r,  fee],    and     Jlf=^.(10+197n+8m2).e2    [5259^,  [52filA] 


556 


THEORY  OF  THE  MOON 


[Méc.  Cél. 


[5262] 


C"-{^.  eV. sm.(2cv—2v-\-2mv-\-c'mv—'2.rs—-ui') 
+  C'f>.  è'e'.sm.{2cv—'2.v+2mv—c'mv—2^+^'), 


1 

2 


it  becomes, 


[526H3 

[526U] 
[526U] 

(5261m] 
[5261 n] 


^Ma 


.co%.{2cv—'2v-\-2mv). 


2c—2-\-2m 

Taking   the    differential    of  this    expression,  according  to  the  direction   in  [5259s'],  it 

becomes, 

— |Ma  .  dv  .s\n.(2cv — 2v-\-2mv). 

This  is  of  the  same  form  as  the  first  member  of  [5259m],  and  may  be  derived  from  it,  by- 
changing  M  into  — ^Ma  ;  so  that,  if  we  make  the  same  change  in  the  resulting 
terms,  in  the  second  member  of  [5259m'],  we  shall  get  the  corresponding  terms  of 
[5082s],  depending  on    cV  ;    namely, 

7  „  1 


_2 

3  771 ,  a 


16a, 


.  (10+19ni4-8m2).e% 


■■1: 


.COS. S  — 


-.cos 


-} 


Re-substituting  the  value  of 


•y      3 


2c— 2-(-3m  2c— 2+!« 

[526 1/(],  we  find,  that  the  coefficient  of    eV.cos.S,  is 


[5261 o] 


tlie  same  as  the  first  term  of  [5261c],  which  is  connected  with  the  factor  10-|-1977i+8m''; 
and,  the  coefiicient  of  e-e'.cos.D,  is  the  same  as  the  first  term  of  [5261e],  connected  with 
the  same  factor. 

.The  second  of  the  functions  enumerated  in  [5090p],  is  that  contained  in  the  table 
[50906].  We  sliall  make  the  following  additions,  so  as  to  include  those  terms  of  eV 
which  were  neglected  in  the  former  computation.  The  three  columns  of  the  table 
are  here  marked  the  same  as  in  [5090J]  ;  and  all  the  terms  in  the  third  column  have  the 
aKdv 


[526];»] 


common  factor 

(Col.  1.) 

Terms  of  the  first 
factor  in  [5081], 
between  the  bra- 
ces, 

— 2e. cos. cu 


|-e^.cos.2('u 


/", 


21mS.(2-f-3m).ee' 


(Col.  2.) 

Factor     Q' 
[5081   or  5082s]. 


4.(2— 3m- c) 


cos .  (2r — 2m» —  CV — drnv) 


(Col.  3.) 

Corresponding  terms  of  [5081], 
or  [52Clc,f]. 


2]7/i2.(2+3;n).eV 


3m2.  (2+m).ee'  .„     „  ,     ,      \ 

-— — — - — cos.(2v-2mv-cv-{-c7nv) 

4.(2— m—c)  ^  ' 


+ 


-m- 

21m2e' 

4.(2-3  m  ) 

3m9e' 

4.(2 -m) 


cos(2y — 2mv  —  c'mv) 
.cos.(2î) — 2mv-\-c'mv) 


4.(2— 3m— c 
3m9.  (2+m}.e9e' 


.cos.  S 


4.(2— )n—c) 
63m2.eV 


.cos.D 


16.(2-3m) 
9nfi.  e2e 


16.(2-m) 


COS.  S 
cos.D. 


r    Lommnn    \ 
I        fnclor        i 


The  terms  in  the  third  column,  depending  on  cos.S,  correspond  to  the  two  last  terms  of 
[5261c  line  1];  and,  those  depending  on  cos.D,  correspond  to  the  two  last  terms  of 
[526le  line  1]. 


vil.  i.§17.] 


TERMS  OF  THE  FOURTH  ORDER. 


567 


We  shall  have,  bj  §  15, 


'•21m-.(10-fl9ffi+8w-)+120OT°.^f        Slm^.  (2-f  3;n)  eSm^       ■\ 

16. (2c— 2+3/»)  4.(2— 3^7)         16.(2—3;»)  ( 


+ 


9)nP 


2c— 2+3m 
— 3m3. (10+1 9m+8»t^)  + 1 20m"'. Af>     ,    3/«3.(2+m) 

16.(2c-2+m)  "^  4.(2-Hi-f)    '    16.(2— m) 


i     2 

^   ;  "^       [5263] 


9 


C?>= 


2c— 2+m 


Rediicins;  these  formulas  to  numbers,  we  find,* 


1 

2 


[5264] 


The  function  [4904],  or  aou,  contains  the  two  terms  [5259i],  and  these  produce,  in 
the  first  term  of  [5090^  line  2],  the  terms, 

_2.?!li^.eV.  \  A'[-\cos.S+AJ\cos.D  ]  ; 

which  are  the  same  as  the  terms  depending  on     jf^f^,     A'-^'^     [5261c,  c]. 

The  next  of  tlie  functions  enumerated  in  [5090/;],  is  the  function  [5090^]  ;  and  we 
have,  in  hne  25,  the  neglected  term  3^f\eV.cos..Ç,  corresponding  to  the  second  term 
of  [5-261cline2];  and,  in  [5090o-Iine  24],  the  neglected  term  3^f«'cV.cos.D,  as  in 
the  second  term  of  [526 le  line  2].  Again,  the  term  — 2^î,'"e'.  cos.(2i' — 2mv  —  c'mv),  in 
the  first  column  of  [5090o-],  being  combined  with  3e-.cos.2ct;,  in  the  second  column, 
gives  — 3^1^'eV.cos..5;  corresponding  to  the  term  depending  on  .4^'"  [5261c].  In 
like  manner,  the  term  — 2^^^'e'.cos.(2« — 2mv-\-c'mv)  [50905- col.  1],  being  combined 
with  the  same  term  3fi^.  cos.2cf,  in  column  2,  gives  — 3^^^'eV.cos.D;  corresponding 
to     Ai^     [5261  e]. 

The  last  of  the  functions  [5090p],  is  that  in  the  table  [5090i]  ;  and  we  have,  in  the  first 
column  of  this  table,  the  term  ^i'>e.  cos.(2y — 2mv — cv)  ;  in  the  second  column,  the 
omitted   term     3.^f'ee'. cos.  (ci'+c'mc)  ,     which    produce,  in  the  third   column,  the   term 

^A['\A[^h^e'.cos.S,     neglecting  the  common  factor     -1-".      In  like  manner,  we  have,  in 

the  first  column,  the  term  A[^''ee'.cos(cv+c'mvy,  in  the  second  column,  3.^',''e.cos(2tJ-2?ni'-cw); 
these  produce  also,  in  the  third  column,  an  equal  term  |^',".^<''eV.cos.»S'.  Adding  this 
to  the  preceding  term,  we  get  3A['\A[%"e'.cos.S,  corresponding  to  the  last  term  of 
[5261c].  In  exactly  the  same  way,  we  find,  that  the  terms  of  ci'hi,  depending  on 
A['^'e.cos.{2v — 2mv — cv),  Af^ee'.  cos.(ci' — c'mv),  produce,  in  the  third  column  of  [5090«], 
the  expression     3.^-'\.^f^eV.cos.D,     corresponding  the  last  term  of  [5261e]. 

*  (2936)     Substituting  the  values   [5117,5194,5157,&;c.]  in   [5260,5261,5363,5264], 


[5261?] 

[5261  r] 
[5261 «] 

[526  U] 


we  get     Af^, 
VOL.   III. 


-^  1    J 


C'f\     C"f     [5265]  ;  and  then,  [5262]  becomes  as  in  [526^1, 

140 


[.5261u] 

[52610] 

[5261«)] 
[526 J x] 

[5265a] 


[5265] 


[5266] 


568  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

A'\-^  =     0,744932;  I 

^'(3)  =—0,0153320;  2 

C'f  =     0,563137  ;  3 

C?'  =—0,0235572.  4 
Hence  we  obtain,  in     nt-\-£,     the  two  following  inequalities  ; 

5',88.       .sin.(2cv—2v-{-2mv+c'mv — 2^; — w')  1 

— 0%25.       .s'm.(2co—2v+2mv—c'mv—2^+^').  2 

The  inequalities  cle])ending  on  the  arguments  2cv±c'mv — 2:3^=^',  are  very 
easily  found,  by  considering  the  expression  of  dt  [5081].  This  expression 
gives,  in  that  of     ni+£,     the  inequalities,* 

3/i'^'eV 
2c+m        ^  ^ 

[5267]  3^(9,^2^, 

+  — ^ .sin.(2c« — c'mv — 2^+^')  ; 

2c — m 

and  it  is  evident,  that  they  are  the  only  terms  of  the  fourth  order,  depending 
on  these  arguments.  By  reducing  them  to  numbers,  we  obtain,  in  nt-\-i, 
the  two  following  inequalities  ; 

— 3%1 6.sin.(2cD+c'wîi^— 2tr— ^') 

+  4%50.sin.(2a' — c'mv — 2ra-|-ra'). 

It  is  evident,  from  the  expression  of     dt,     [5081],   that  the  inequality 
depending  on  the   argument      ^v — ^mv — cv-\-ts,     must  be  sensible.!     To 

*  (2937)  The  functions  [5090p],  which  represent  the  value  of  dt,  give,  in 
[5090^  lines  26,27],  the  two  following  terms,  which  were  oniiued  in  that  table  ; 

[5267a]  dt  =  tlp-.éh'.  \  3^i='>.cos.(2cu+c'm«)+3^«).cos.(2CT— c'm«)  | . 

\  a-  ,  , 

Dividing  this  by     -  =  -—      [5092c]  ;  and  then  integrating,  we  get,  in     nt-\-e,   the  two 

terms  [5267].  A  slight  inspection  of  the  functions  enumerated  in  [5090p]  shows,  that  there 
are  no  other  terms  of  this  form,  and  of  the  fourth  order. 

f  (2938)  This  will  fully  appear,  by  the  inspection  of  the  terms  of  7i;-|-s,  depending 
on  this  argument  in  [5280,  5281 ,  5283]. 


[5267'] 


[5268] 


Vll.iU?.]  TERMS  OF  THE  FOURTH  ORDER.  569 

determine  it,  we  shall  represent  the  corresponding  term  of    aàu,     by 

uiu  =  ^'^•"e.cos.(4î; — ^mv—cv-\-zi).  [sacyj 

It  is  evident,  that  there  cannot  be  produced  such  terms  in  the  differential 
equation  in    «    [4961],  except  by  the  variation  of  the  terras  of  the  equation     [5269'] 
[4754],  depending  on  the  disturbing  force.*     We  have   developed  these 

^ÎM       7/  OH 

variations  in  ^  8.     The  first  is     —  '-    "      :     and  it  produces  no  term  of     [5270] 

the   fourth  order,  depending  on     cos.  (4î; — 4?au  —  cv-\--a).      The  second 
variation  is,t 


*  (2939)     This   is   evident,  from  the  examination  of  the  functions  [4960e],  which 

compose  the  equation  [4961]  ;  since  the  terms  enumerated  between  [4866]  and  [4901]  do 

not  contain  the  angle   Av — 4my — cv.     The  next  of  these  functions  is  that  in  [4908],  which    L5269a] 

3î^t .  Î/  •  ou 
arises  from  the  development  of    —  — nUTZ —     ['^SOSg']  ;  and  we  find,  by  inspection,  that 

it  contains  no  term  of  the  fourth  order,  depending  on  this  angle.  The  same  may  be 
observed  of  the  functions  [4913,  4918,4922,4928,  4942—4960].  The  three  remaining 
functions  [4911,  4925,4934],  which  are  derived  from  the  quantities  mentioned  in 
[5271,  5273,  5275],  produce  some  important  terms,  as  will  be  seen  in  the  following  notes. 


[52G96] 


t  (2940)  This  expression  is  the  same  as  that  in  [4910],  which  is  developed  in 
[4911,  4918].  The  term  depending  on  the  second  of  these  functions,  is  retained  by  the 
author,  though  it  produces  only  terms  of  the  fifth  order  [5271c].  Substituting  the  values 
[4937n,  5082Â'],  in  [5271],  it  becomes. 


_2  _2 


—   - — .adu.cos.{2v — 2mv)-] .5î)'.sin.(2tJ — 2m«).  [5271al 

Now  we  have,  in  [4904  line  2,  4917],  the  terms  of    ahi,     ôv',     represented  by 

a&u=  A[^'' e.cos.{2v — 2mv — cv);         ôv':= — 2m..^',"e.sin.(2«j — 2mv — cv).  [52716] 

The  first  of  these  quantities  produces,  in  [.5271a],  the  term, 


4  a. 
and  the  second,  the  term, 


9m 

J — .A[^''  e.cos.{4v — 4mv — cv)  ; 


..^'i".7ne.cos.(4îJ — \mv — cv)  ;  [5271c] 


the  sum  of  these  two  expressions  is  evidently  equal  to  that  in  [5272]. 


560  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Qm'   )/'3  :î  m'  9/3 

[5271]  _    7  ;'^     .6^.cos.(2;;-2t)')  +  -^^  .6tj'.sin.(2t— 2«')  ; 

it  produces  the  term, 
[5872]  —  — -.(3— 4m).J',"e.cos.(4« — 4>mv — cu+^). 

The  third  variation  is,* 


[5273] 


[527:3tt] 


,o    4    •  -T-  •  — .sin.  C2v— 2«')  —  ,,yw— r.  -,— .sin.(2«— 2?;') 
h-.u*      dv      u  ^  '         2/iMt'     dv         ^ 


u 

3m'.u''\6v'  du 
h^.  u^       dv 


+    /.2..4    •:7::.cos.(2i>-2t>0. 


It  produces  the  term, 


3  7ft 

[5274]  —  -^ — .(2 — 2m — c).JJ'^e.cos.(4t' — ^mv — cv+z^). 

Lastly,  the  fourth  variation  is,t 


*  (2941)     The  three  terms  of  the  function  [5273]  are  the  same  as  those  in  [4924J, 

which  are  developed  in    [4925].      The  first  of  them  is  computed  in   [4923f,  &c.],   and 

evidently  contains  no  term  of  the  fourth  order,  depending  on  the  proposed  angle.    The  same 

is  to  be  observed  of  the  third  term  of  [52  73],  which  is  computed  in  [4923(7].     Tlie  second 

term  of  [5273]  is,  _  3m'. «'^     dSu^  ^.^^       ^  _  ^ 

2^2.  „4  •    dv  •-     •V*'  "J' 

and  it  becomes,  by  substituting  the  values  [4937?^,  4865], 
[52736]  .  — = sm .  (2  u  —  2  m  v  ) . 

]\ow,    =  —  ,   -     contams,  m  [49041ine2],  the  term, 

dv  dv 

r  5273c]  —  ("2 — 2m — c).-4j"e  .sin.(2« — 2mv—cv)  ; 

hence  the  preceding  expression  produces  the  term  [5274],  as  is  evident,  by  multiplying,  and 
reducing  the  product  by  means  of  [17]  Int. 

■f  (2942)     The  expression  [5275]  is  ths  same  as  that  in  [4931],  which  is  developed  in 

[5274a]     [4934],  by  means  of  the  functions  enumerated  in  [4932A:]  ;  namely,  [493 Ip,  h,  4932a,/]. 

The  first  of  these  functions  [493 Ip]  contains  in  its  second  line,  a  term  of  the  fifth  order, 

depending  on     .41"',     which  is  neglected  on  account  of  its  smallness.     It  also  contains  a 

term  depending  on    A'-^\     which  is  omitted  in  [4931  p  line  6],  but  is  easily  found,  by  the 


Vll.i.<^17.]  TERMS  OF  THE  FOURTH  ORDER.  661 

-—.  { l+Îj"-.cos.(2^i— 2<))  \ ./  —i-  •  J  -  -sin.  (2«-2«')  +h^v'.  cos.(2«-2.')  [ 

ft    <  (t  1.1  f   11  ^ 

[5275] 

it  produces  the  term, 

a,  4 — 4?« — c  ^  ^ 

Therefore,  the  differential  equation  in     ii     becomes,  by  noticing  only  these 
terms,* 


method  there  used,  to  be,         g  --  j 

.  — — , .^'•'e.cos,(4ti— 4mw— cd):  [52745] 

«^       4 — 4w — c  ^  " 

neglecting     e-,     and  putting, 

Ti^A^^^e;     A:' =  1  ;     i=2— 2m— c;     {'=  2— 2m    [4931/].  [52746'] 

This  is  the  same  as  the  fast  term  of  the  expression  [5276].  The  .next  of  the  functions 
[5274a]  is  [493  Iw]  ;  which  may  evidently  be  neglected  on  account  of  its  smallness.  We 
then  have  [4932a],  which  contains,  in  its  first  line,  a  term  depending  on  A^^,  which  is 
omitted  in  the  table,  but  is  easily  found  to  be, 

2 

Qlii  m 

- — •  •  -; — .^i"e.cos.(4n — A.mv—cv).  r5'274cT 

a,       4— 4m — c  '  ^         ^ 

The  last  of  the  functions  [5274cr]  is  [4932/]  ;  this  also  contains  a  term  which  is  neglected 
in  its  sixth  line,  and  is  represented  by, 

■iïï?    r  (2— 2m— c)2-l  ^ 
~    2^'  ^ 2:(lZ:5,"^   5  ■  ^'."^  •cos-(4r— 4mr— CT).  [5274rf] 

This  may  be  reduced  to  another  form,  by  observing,  that,  by  putting  c=l,  we  have, 
very  nearly,  (2— 2  m— c)'^- 1  ={\—2mf—\  =  —/^m;  so  that  this  term  may  be 
represented  by,    - 

_2  2 

3   JÏI  .,,,  lA  A  \  37/Î  3  7?l 

—  .m.A'^e.cos.(4«-4mt— f.),     or,     —.  .j--^__.^me.cos(4z;-4mt;-aO,  nearly.     [5274e] 
Adding  this  to  the  term  [5274f],  we  get, 

2 

3  m,  5m 

^  •  4  -  4,„_^-^'/^e-cos.(4i;— 4m^)— ct),  [5274/] 

as  in  the  second  term  of  [5276]. 

*  (2943)     Adding  together  the  terms  [5272,  5274,  5276],  we  obtain  those  connected 
VOL.  III.  141 


662  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

_  2 

[5277]     0  =  -r^+u .  <  5— 6m — c-\ — ^^ -•  >  .  J  "e.cos/4v— 4mi>— c«;+ra). 

dv~  4«,      (  4 — 4m — c    )       '  ^ 

If  we  substitute  in  it,  for     a&u,  tlie  term, 
[5378]  aiu  =  ^'^%.cos.(4i)— 4mt;— CT+ra)     [5269], 

we  shall  (ind,* 

3m2 


[5279]  ^'(^) 


3 


!L.;5-6m-c+i:fcMr^a, 

[         I  '  4  — 4)n— c    )         ' 

(4_4m— c)-— 1 


Then,  if  we  put 
[5a80j  C(^'e.sin.(4z)— 4mi;— cw+ra), 

for  the  corresponding  term  of    nt-\-s,     we  shall  have,  by  ^  15,t 

with     COS.  (4î) — Aim — cv),    in    [5277];    to  which  we  must  add,  as  in  [5241c],  the   two 
terms     -r^-\-u,    to  obtain     [5277]. 

*   (2944)     Substituting,  in    [5277],    the   assumed  value  of    au,     or     «(5m     [5278]  ; 
[5279a]    jj^^jjjj^tQf    „,2     [5082A'],  we  easily  obtain  the  expression  of    A^^''     [5279]. 

•f    (2945)     Proceeding  as  in  [5261a,  &;c.],  we  may  take  the  differential  of  the  term  of 

[5281a]    nt-{-s     [5280],  and  multiply  it  by     -  =:  —      [5092c],  and  we   shall   get,   in     dt,     the 

term,  _        „2.rfi, 

[52816]  dt^  (4 — 47ft — c).C^^'e.-— — .cos. (4?; — Amv — cv). 

Substituting  the  assumed  value  of     C'^'",     we  find,  that  the  result  is  represented  by  the 
function  [5281(/],  or  the   numerator  of  the  expression  [5281],  multiplied  by  the  common 

[5281c]  e._.cos.(4.-4m.-czO; 

and,  we  shall  find,  upon  examination,  that  if  we  neglect  the  consideration  of  this  factor,  the 
corresponding  terms  of  the  value  of    dt     [5090p]  will  agree  with  the  function  [5281rf]. 

f       3m2        ,    3m^.(l-»«)  ,    3j(0)  ?      A^^)_OA'W 
[5281rf]  [  ^^11^)  +    4-4m-c   ^  '^:^     J  •^.         ^^3   • 

To  prove  this,  we  shall  now  compare  this  expression  with  that  which  is  derived  from  the 
[52816]     fonctions  [5090p].     The  first  of  these  functions  depends  on  [5082«],  or  the  value  of     Q' 
[5082<7]  ;  and  this  last  function  contains,  in  [50825  ^'"^  ^l'  ^^^'^  t^™  terms, 


VII.  i.<^17.]  TERMS  OF  THE  FOURTH  ORDER.  563 


i.(l— m)    ^    4— 4m— c  S        ' 


^,„  ,    4.(1— m)     '     4— 4m— c   '    ""'     S'"'  ' 

C'^)  =  -!^ ^ >- — ! [5281] 

3  4 — 4m — c 

Reducing  these  formulas  to  numbers,  we  obtain, 

yj'(4)   =—0,000799351  ;  l-'5'-^82i 

C'^4)  =     0,00294934.  t^^^^'l 

Hence  arises,  in  the  expression  of    nt-\-i,     the  inequality,* 

33%38.sin.(4y— 4m«— cî5+^).  [5283] 

The  inequality  depending  on     4t?— 4mw — 2cw+2a,    may  also  be  sensible  ; 
the  expression  of  ndt     [5081,  &.C.]  contains  the  following  quantity,! 

— |a  X  function  [493 Ip],     — iaX  function  [4932a].  [5281«'] 

Now,  the  omitted  term  of    — JaX  [4931jjline6],     produces  the  term, 
_a 

^^^^    . ^ .^i"e.cos.(4^  — 4mr  — c«);  [5281/] 

a,  4— 4m— e  ^  ' 

and,  that  in     — ^ax[4932(dinel],    gives, 

—  ^^H-f.  .  .^L .  ^(ne.cos.(4y— 4Mr— ct).  [sasi/-] 

a,  4 — 4hi — c  ^ 

The  sum  of  these  becomes,  by  using  the  value  of    ir?     [5082A'], 

37n".(I — in)      ....  ,.  .  . 
!^ ^.yJ  '*  e.cos.  (4î)  —  \mv — cv\,  r5281s'l 

corresponding  to  the  second  term  of  [5281f/].  The  next  of  the  functions  [5090p]  is  [5090i]; 
it  produces  nothing.      The  term  depending  on  [4904]  produces     — 2^'Ç,'",     as  in   the  last 

terra  of  [5281  rf].     The  term  omitted  in  [5090^  hne  11]  gives     -— ',     as  in  the  first     [528U] 

term  of  [5281c/].     Lastly,  the  double  combination  of  the  terms 

^^">.cos.(2u— 2mi;),         A^}\.co'i.{1v—9.mv—cv)     [5090/],  r5281»l 

gives,  by  a  process  like  that  in  [5261m,  &.C.],  the  term     ZA^^^.A^l'^ ,     as  in  the  third  term  of 
[528  If/]. 

*  (2946)     Substituting,  in  [5280],  the  values  of     C'f,      e    [5282',  5194],  it  becomes 
as  in  [5283].  ^^^^^^ 

t  (2947)     If  we  examine  the  functions  contained  in  the  expression  of    dt     [5090p], 


564  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5284]  i'iA^'Y-  ^^'  dv.cos.{^v—^mv—2cv-\-2Ta). 

Hence  arises,  in     nt-{-=-,     the  term, 

3.(  J^")-.  â.  sin.(4?;— 4ot«— 2ct+2^) 
t^^s^J  2.(4— 4m— 2c)  " 

It  is  evident,  that  it  is  the  only  terra  of  the  fourth  order,  depending  on  the 
same  argument,  which  enters  in  the  expression  of  nt-\-s.  Reducing  it  to 
seconds,  it  becomes, 

[5286]  22%26.sin.  (4v— 4w«— 2cr+25,) . 

We  shall  see,  in  [5578 line  10],  that  the  tables  of  Mason  and  Burg  both 
[5286]  agree  in  making  the  coefficient  of  this  inequality  nearly  equal  to  15'  ; 
which  seems  to  indicate,  that  this  coefficient  is  well  determined  by 
observation  ;  consequently,  the  difference  7',  between  this  result  and  the 
preceding  computation,  must  arise,  in  a  great  measure,  from  the  quantities  of 
the  fifth  order,  which  we  have  neglected.  To  prove  this,  and  to  show,  at  the 
same  time,  that  a  farther  approximation  will  diminish  the  difference  between 
[5286'"]  the  theory  and  observation,  we  shall  proceed  to  determine  this  coefficient,  so 
as  to  include  quantities  of  the  fifth  order. 

We  shall  denote  the  corresponding  term  of     adu,     by 

[5287]  a&u  =  J'f'e^cos.(4r— 4»ji;— 2ci'+2^). 

It  is  evident,  that  terms  of  this  kind  are  produced  in  the  differential  equation 
[4961],  solely,  by  the  variation  of  the  term  of  the  equation  [4754],  arising 
from  the  disturbing  force.  We  have  just  given  the  four  variations  of  these 
[5967]  terms  [5270 — 5275].  The  first  variation  [5270],  produces  no  term  of  the 
fifth  order,*  depending  on    cos.(4y — 4OTy — 2cv-{-2^).      The  second  variation 


we  shall  find,  that  the  term  [5284],  with  the  factor      — -  ,     is    omitted    in   [5090nine7], 
[5284o]  ^''' 

and  this  is  the  only  term  of  the  fourth  order,  depending   on  the   angle     Av — Amv—2cv. 

The  integral  of  this  expression,  being  divided  by     -      [5092c],   gives    the    corresponding 
[5-2845]  " 

termor    nt-\-i    [5285].     Substituting  the  values  [5117,  5194,  5158],  we  get  [5286]. 

*  (2948)     The  computation  of  the  terms  of  the  formula  [5290],  is  made  in  the  same 
[5--.86a]    j^j^jing,.  as  that  in  [5277]  ;    the  former  being  multiplied  by    e^,    and  the  latter  by    e;    so 


VII.  i.  §  17.]  TERMS  OF  THE  FOURTH  ORDER.  565 


[5271]  produces  the  term 

9  m' 


4ii. 


l2A['^—A["^.e\cos.(4>v—4imv—2cv+2i^).  [5288] 


The    terms   of  the   fifth  order,  depending  on     cos.(4« — 4m  « — 2cv-\-2-ui), 
which  are  produced   by  the  third  variation  [5273],  mutually  destroy  each     [5288'] 
other,  except  in  quantities  of  the  sixth  order.f     Lastly,  the  fourth  variation 


that  tlie  similar   terms   of  [5290],  are  of  a  liigher  order  by  unity,  than  those  of  [5277]  ; 

and,  in  retaining   terms  of  the   fifth  order  [5286'"],  we  shall  have  to  notice  only  the  same     [52866] 

functions  as  in  [5271,  5273,  5275]  ;  that  in  [5270]  being,  as  in  the  former  case,  insensible. 

*  (2949)     The  terms  of  the  second  variation  [5271]  are  developed  in   [4911,4918]. 
The    last   of  these  expressions  produces,   in    [4918,  4918/],  terms    of  the   sixth   order 
containing     e~,     which   may  be  neglected.       The  first   term  of  [5271],   is   found   as  in     [5288a] 
[4910/],  by  multiplying   the    function  [4910/.:]  by     2o5i«     [4904].     Now,   if  we  combine 
the  term, 
a 

— —  .cos.(2j;— 2mu)    [4910;i-line  1],     with     2^',"'e2.cos(2cy— 2y+2mz;)    [49041inel2],    [52886] 

—  —  .^',"'e2.cos.(4u— 4mi' — 2cv),    as  in  [5288];  [52886'] 

4a, 

and,  if  we  combine  the  term, 

9ift 

—  .e.cos.(2u— 2mi)— ct)  [4910A:line  2],   with     2A-Pe.cos.{2v—2mv—cv)  [49041ine2],    r5288e1 

we  get,  9-2 

--.Al''e^.co5.{Av—Amv—2cv),  as  in  [5288].  ^5288rf] 

The  remaining  terms  of  the  sixth  and  higher  orders  are  neglected. 

t  (2950)     The  first  term   of  [5273]  is  represented,  in  [4923e],  by  the   expression 
—.4a(5«X  function  [4879]  ;  and  the  only  terms  of  [4904],  necessary  to  be  retained,  are  those     [5288e] 
depending  on     A['^\     A^^\     which  may  produce  quantities  connected  with     e^.      Now, 
by  retaining  only  the  quantities  which  are  multiplied  by     e^. cos.(4t) — Amv—2cv),     we    rsage/'l 
find,  that  the  term  depending   on      Ai^'>     [4904  line  1],   combined   with    [4879  line  7], 
produces  a  term  of  the  sixth  order,  which  may  be  neglected.     The  term, 
— AA^^h .  cos.(2u — 2mv—cv)     [4904  line  2], 

multiplied  by,  g-^ 

j-.e.cos.(2z)— 2mt; — cv)     [48791ine  1],  [5288g] 

VOL.  in  142 


566  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5275]  produces  the  term,* 

r53891        ^  \  5^-g^"      (l-2m).(3-2,.,).(10+19»»+8;».^)  ^,o,,^^ }  o  /4.-4^. 

^        '         2a     i  2—2m—c  4.(2c— 2+2m)  '     '"^2-2»!$     *  \-2CTf2n 


produces  qu 

[5288/1]  —  -^■A'^e-'.cos.{4v—4mv—2cv)  ; 

and  this  is  the  only  term  of  [5288e],  which  is  of  sufficient  importance  to  be  noticed.  The 
second  term  of  [5273]  is  developed  as  in  [4923r]  ;  and  a  little  attention  will  show,  that  the 
only  term  of  whi  [4904],  necessary  to  be  noticed,  is  ./3^''e.cos.  (2  «  —  2}nv — cv), 
[5288i]  corresponding,  in  [4923iy],  to  k^=A[''>e,  f^2— 2m— c=l,  nearly.  Combining  this 
with  the  terra     fc'.cos.v'     [4923u,  4885  line  2],  which  is  nearly  equal  to 

—  2ê.cos.  {2v  —  2m  V  —  cv)  ; 

making     k' = — 2e,     y'=z2v — 2mv — cv;     we  get,  for  the  second  term  of  [4923a;],  the 
expression, 

[5288fc]  —^.ikk'.cos.Uv—4mv—2cv)  =   —.A['k^.cos.{'iv—4mv—2cv). 

4«,  2ffl, 

This  is  equal  to  the  term  [5288/i],  but  has  a  different  sign  ;  so  that  the  two  terms  destroy 
each  other,  as  in  [5288']  ;  therefore,  the  whole  of  this  function  may  be  neglected. 


[5289a] 


*  (2951)  The  fourth  variation  [5275  or  4931]  is  developed  in  the  functions  which  are 
enumerated  in  [4932/i:]  ;  namely,  [4931p,u,  4932tt,/].  Now,  the  first  of  these  functions 
[493  Ijj]  gives  a  term,  which  is  produced,  by  combining,  in  the  manner  explained  in  [4931  n], 
the  term  ^'j''e.cos.(2« — 2m» — cv),  of  the  first  column  of  [4931pline6],  with  the  term 
— fc.sin.(2u — 2mv — cv),     in  its  second  column  ;  which  give, 


__2 

6m 


[528911  —4A[^\ .co^.{4v—4mv — 2cv),  as  in  the  first  term  of  [5289]. 

In  like  manner,  the  combination  of  the    term     A['^'^e^.cos.{2cv — 2v+2mv),     in   the  first 
column  of  [4931p  line  25],  with    sm.{2v—2mv),     in  its  second  column,  gives, 

o 

[5289c]  ^  .  -4j"^. .cos.(4y — \mv — 2cv),   as  in  the  second  term  of  [5289]. 

«, 

The  function   [4931m]   contains  nothing  of  the   proposed  form  and  order.      The  function 

r4932«]  contains  a  quantity  depending  on     A-^^     of  the  sixth  order,  which  is  neglected  by 

[5289d]     the  author,  on  account  of  its  smallness.     The  last  of  these  functions  is  [4932/']  ;  it  contains 

a  term  of  the  proposed  form,  which  is  found  by  combining  the  term  .^l'".cos.(2i,' — 2mv),  in 

column    1    of  [4932/line  1],   with    the    term    of   its   second    column,   corresponding   to 

[4885  line  10],  _(l^±1^!^±^'^.eS.cos.(2c.-2.+2m.). 

[5289c]  4.(2c— 2+2m)  ^  ' 

This  term,  found  by  the  method  in  [4932f'],  is, 


3^(')— |4""+-P^^^^i-+Ar..  )  1 


VlI.iU7.]  TERMS  OF  THE  FOURTH  ORDER.  667 

Therefore,  the  differential  equation  [4961]  becomes,  by  noticing  only  these 
terms,* 

(+  4.(2c— 2+2/«}  ■      -  ) 

Substituting     J'f ^e^  cos.  (4z; — 4»i« — 2c?;+2ra)     for     a^M,     we  obtain,  [5291] 

2— 2m— c    "^2— 2ot 

(I_2,„).(3_2,„).(l0+l9m+8m^j      ^^^o 

^,(5,  _    ^J!r\l 4.(2c-2+2m) ^    )  [5292] 

3     —     2    •  (4_4„t_2c)2— 1 

If  we  denote  the  corresponding  term  of    nt-\-i     by 

C"f'e^.sin.(4r— 4m?;— 2c«+2î!),  [5293] 

we  shall  have,  by  ^  15,t 

_2 

^ .  M.(l_m)2_l  ? /10+19"'+8^),^(o)g3^.os.(4t,— 4mf— 2ct)  ;  [5289/1 

and,  by  using  the  reduction  4.(1— ?h)" — 1==(1 — 2m). (3 — 2m)  [4961A],  it  is  easily 
reduced    to   the  form    of  the  term  depending  on     A°'^     [5289].      Lastly,    the   term 

./3<»ie2.cos.(2ci— 2u+2fflr)     [4932/ col.  1],  being  combined  with     """"'^""^""'^  in  col.2, 

gives  2~'â^~  '  ^^  '"  [5289];  observing,  that  in  this  case,  the  factor  — (i^ — 1) 
[4932c']  is  nearly  equal  to  unity  ;  since  i  =  2c — 2+2m  =  2m,  nearly.  The  remaining 
terms  of  these  functions  are  neglected  by  the  author,  on  account  of  their  smallness. 

*  (2952)     Adding  the  terms  [5238, 5289],  and  connecting  the  sum  with  the  two  terms 
^+u     [.5241c],  we  get  [5290].     Substituting  in  it  the  assumed  value  of    aU   [5291],     [5290a] 
and  using     n?     [5032^'],  we  get     ^'^=>     [5292]. 

t  (2953)     By  proceeding  in  the  same  manner  as  in  [5245a — c],  we  find,  that  the  term 
of    nt-\-i     [5293],  gives,  in     dt,     the  term, 

dt=  (4— 4m— 2c).  CT'e^.  ^^  .cos.(4w— 4mj;— 2c«).  [5294o] 

Comparing  this  with  the  terms  of  at  [5030p],  we  get,  for  C'l'\  the  same  expression 
as  in  [5294]  ;  or,  in  other  words,  the  terms  of  the  functions  [5030p],  being  divided  by  the 


668 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


[5294]       Cf)    = 


— 3m2.(5^f,'>— 2^i"') 


STmi         (10-fl9m+8m2) 


4.(2— 2»»— c) 
3m^ 


64.(1— m)         2c— 2+2m 


•^1 


T^'^^a     i4.(i_,„)—i  4— 4rti 


3m2.^<"  3m^(10+19m+8m3) 

""      ^  8.(2c— 2+2"/ft)r~" 


(0) 


4— 4m — 2c 


2 
3 


[52945] 


common 


factor 


,  a2.  dv 


cos.(4t) — 4m  V — 2cii), 


[5294c] 

[5294rf] 

[5294e] 


produce  the  terms  in  the  three  lines  of  the  numerator  of  the  expression  [5294],  as  will 
appear  by  the  following  examination.  The  first  of  the  functions  [5090p]  represents  the 
value  of  Q'  [50S2«  or  5082q].  Now,  the  last  of  these  expressions  [5082<7  line  2] 
contains  the  terms, 

J.function[4885]— i.function[4889] — ^«.function  [4931jj]— Aa.function  [4932a]; 

which  we  shall  separately  examine.  The  mere  inspection  of  [4885,  4839],  shows,  that 
they  produce  nothing  of  the  proposed  form  and  order.       The  next  of  these  functions  is 

—  JaX  function  [4931^]  ;     and,  as  the  common  factor  of  the  terms  of  this  table  is  — ,  we 

have,  by  using  [5082A'],     — |aX —  =  — 3m~  ;     Then,  by  combining,  as  in  [4931n], 

the  term  ./3<i"  e.cos.(2«  —  2mv  —  cv),  of  the  first  column  of  [4931pline  6],  with 
— |.e.sin.(2t) — 2mv — cv),     of  its  second  column,  we  get, 

[5294/]         — 3m,^4A[^'>e^.  . .    ^y  .cos.{Av  —  4mv-2cv),     as  in  the  first  term  of  [5294 line  1]. 

In  like  manner, the  term  A[^^'^e^.cos{2cv — 2!y-l-2my),  of  the  first  column  of  [4931/?line25], 
being  combined  with     s\n.{2v  —  2mv),     of  its  second  column,  gives, 

[5294^]        3/«^.^'"'e^. /_^.    n   •cos.(4t) — imv — 2cv),     as  in  the  second  term  of  [52941ine  1]. 

The  last  of  the  functions  [5294c]  is  that  depending  on  [4932a],  which  upon  examination, 
is  found  to  produce  no  term  of  the  required  form  and  order.  Besides  these  terms, 
arising  from  the  value  of  Q',  [50S2«  or  5082(7],  we  must  add  a  term  we  have  formerly 
neglected,  in  finding  the  value  of  f  711^,  which  makes  a  part  of  the  value  of  Q'  [5082m]. 
For,  it  is  evident,  that  in  deducing  the  value  of  f^/K^  [5082o],  from  that  of  M, 
[5082n],  we  have  neglected  the  term, 

^''"''    .P,.cos.(4i;— 4my+F)     [5082oline2]  ; 


[5294A] 


[5294i] 


[5294i'] 


16.(1— m) 

supposing,  as  in  [5082n,  &;c.]  that   P,.  cos.  {2v — 2mj;-f  V)    represents  any  term  between 
the  braces  in  [4885].     Now,  if  we  take  this  term,  in  [4885  line  10],  we  shall  have, 

(10-|-19OT+8rt.2) 


P,=- 


4.  (2c— 2+2/») 


•e-; 


[5294m] 


VII.  i.  §  17.]  TERMS  OF  THE  FOURTH  ORDER.  569 

Reducing  these  formulas  to  numbers,  we  find,  [5294'] 

and,  by  changing  the  signs  of  the  angle  in  [4S851inelO],  to  make  it  conform  to  [5082«],  we 

get   V  =  -2cv  ;  substituting  tliese  in  [5'294iJ,  it  becomes,  without  noticing  the  factor   — — , 

aim-»  (10+19«+8/«s)    „ 

-  64:0"-^  •       2c-2+2rn     •^^•«o^4._4m.-2a-)  ;  [5294*] 

as  in  the  third  term  of  [5294  line  1].     The  next  of  tlie  functions  [5090/)],  is  that  in  the 
table  [50906].  This  contains  a  quantity,  which  is  found  by  combining  the  term   -2e.cos.c« 

3m- 

[50906 col.  1],  with  the  term     ———— .A\''>e.cos.{4v—4mv—cv)  of  Q',  in  [50906 col. 2]. 

This   term   was    omitted  in   [49.3I/jline6],    and    also    in     — JaX  function  [493 Ip],    in       [5294/] 
computing  the  value  of     Q'     [50S25'line  2].     The  combination  of  these  two  terms  of  the 

table   [50906],  gives     —   j—^-^—.A'^'^c^.cos.lév—imv—cv),  corresponding  to  the  third 

term  of    [5294  line 2].     In    the  original  work  the  divisor      4 — 4m — c     is   inaccurately 
printed,  being  put  equal  to     2 — 2in — c. 

The  term  depending  on     —  [4904]x2.^^,     in  [5090/? line 2],  gives     ~2A'^=\     by 

using  the  term   of    aSu     [5287];    this  agrees  with  the  last  term  in  [52941ine  1].     The      [5294n] 
next  of  the  functions  [5090p]  is  that  in  [5090^],  whicli  produces  several  terms.   Thus,  by 
combining  the   term  of     —2a'hi= —2A'l,'^''e.cos.(4v—imo~cv)      [5278],  which  would 
occur  in  the  first  column  of  [5090j],  witli  the  term     — 3e.cos.c«,     in  its  second  column, 
we   get     3^V*e^cos.(4w  — 4mv— 2:i)),     corresponding  to   the  first  term  in  [5294  line  2].       t^^'*"] 
In  the  next  place,  the  term  —2A["'>e^.cos.{iicv—2v^2nv),  in  column  1  [5090^1ine23], 

being  combined  with     —  jrj^— r-  cos.{2v—2mv),     in  column  2,  gives, 

-^jY—^.A[''^e^.cos.{4v—4mv—2cv),  [5294pj 

corresponding  to  the  second  term  of  [5294  line  2].  Again,  the  term  — 2^,;'".cos(2y-2/««), 

in   tlie    first   column    of   [5090^  line  1],  baing  combined  wltii   that  term   of   its  second 

column,  which  is  contained  in  the  first  line  of  [5090e],  bymeans  of  the  term  [5082*  line  10]; 

namely,  3rf^^0±\9m-j-8nf')     o         ,„        „    ,  „     , 

-^^^^—^^;i^.e~.cos.{2cv-2v+2Mv), 

produces  the  term, 

— 3w^.(10-fl9ffi+8m^) 

8.(2,_2^2m)  -A'e  ■cos.{4v-4mv-2cv),  [5394,^ 

corresponding  to  the  last  term  in  [52941ine2].  Thelastof  the  functions  [5090p] is  [5090e]. 
This  produces,   in    [5090nine  7],  the  term     i.(A['^f.e^.cos.{4v—4mv—2cv),     as  in  the     [5294r] 
first  term  of  [5294  line  3].     The  combination  of  the  term     AfKcos.(2v—2mv),     in  the 
VOL.  III.  143 


570  THEORY  OF  THE  MOON  ;  [iMéc.  Cél. 

[5395]  *^'f  =  0,00436374  ; 

[5295']  Cf  '  =  0,0249067  ; 

which  gives,  in     nl-j-^,     the  inequality, 

[5296]  15',46.sin.(4«— 4wiîJ — Sczj  +  S^j). 

The  difference  between  this  result  and  that  of  the  tables  is  insensible  ;  and 
[5396]  we  see,  hy  this  calculation,  that,  to  make  the  theory  agree  wholly  with 
observations,  relative  to  all  the  lunar  inequalities,  it  is  only  necessary  to  carry 
on  the  approximation  to  quantities  of  the  fifth  order.  This  appears  also  from 
the  calculation  of  the  inequality  depending  on  sin.(« — mv),  in  which  we 
[5396"1  ^^^^^  noticed  quantities  of  that  order.  For,  we  shall  hereafter  find  [5589],  that 
the  result  of  this  analysis,  compared  with  that  which  is  obtained  by  observation, 
gives  nearly  the  same  value  of  the  sun's  parallax,  as  that  which  is  deduced 
from  the  transits  of  Venus  over  the  sun. 

The  inequality  depending  on  the  argument  cv  —  v-if-mv  —  ra  may  be 
sensible,  on  account  of  the  smallness  of  the  coefficient  of  v.  To  determine 
this  inequality,  we  shall  put. 


[5294«J 


[5294<] 


first  column  of  [5090i],  wilh  3A[^'^e-.cos.{2cv — 2v-\-2mv),  in  the  second  column, 
produces  # -^L"'.  ./3*"V;^.cos.  (4  i' — 4mv — 2cv);  and  the  similar  combination  of 
A\^^''c^.cos.{2cv—2v-\-'2mv),  in  the  first  column,  with  ^^'''.cos.(2r — 2?ot),  in  the  second 
column,  gives  an  equal  quantity,  §yi„^".^<j"V2.cos.(4r — 4mv — 2cv)  ;  the  sum  of  these 
two  terms  is  3^i,'".^'/''e^.  cos.  (4« — 4mv — 2c?)),  corresponding  to  the  second  terra  of 
[5294  line  3].  In  exactly  the  same  way,  we  find,  that  the  double  combination  of  the  terms 
A'-°\co5.{'2v — 2mv),  A^^e.cos.{2v — 2mv—cv)  [5090J],  produces  in  that  table,  or  in  the 
value  of  3.{aiu)-,  the  term  3^^''^^^"e.cos.(4î)— 4wt!— cy)  ;  and,  if  we  multiply  this 
\)y  — 4e.cos.cu,  which  was  neglected  in  [5090/<;],  it  produces  the  term, 
f5294M]  —6£'„''\^[^^e^.cos.('iv—4mv—2cv), 

corresponding  to  the  last  term  of  [5294  line  3]. 

*  (2954)  Substituting  in  [5292]  the  values  [5117,  5157  —  5167],  we  get  for  A'^^'\  a 
[5295al     value  which  is  nearly  equal  to   that  in   [5295].     Using   the  same  in   [5294],  we  get    for 

C'?''  a  value  which  exceeds,  by  a  small  quantity,  that  in  [5295].  This  difference  is  owing 
[52956]    jQ  ji-jg  inaccurate  divisor  of  the  term  mentioned  in  [5294»!].     Substituting,  in    [5293],  the 

values  of     C"-J'\   c    [5295',  5194],  we  get  [5296]  ;  the  coefficient  would  be  increased  about 

[5295c]  ;  ,  ,.    .  .        rrr.n^      1 

P,  by  correcting  the  divisor  as  m  [5294?»]. 


Vll.i.^17.]  TERMS  OF  THE  FOURTH  ORDER.  671 

aiu  =^  A' f''.-,.e. COS. (co — v-\-mv — 3j)  ;  [5297] 

and  ^ 

C'^'.-,.  e .  sin.  (cv — v+mv — w) ,  [5298] 

i     a  ^ 


for  the  parts  of  aSii  and  nt+s,  depending  on  this  argument,  we  shall 
have,  by  noticing  the  perturbations  of  the  earth  by  the  moon,* 

*  (2955)     In  this  note  we  shall  put,  for  brevity, 

V  =  cv  ■ —  V  -]-mv  —  «  ;  [5297a] 

and  we  shall  then  examine  successively  the  functions  enumerated  in  [4960e],  for  the  purpose 
of  collecting  together  the  terms  ofthe  equation  [49G1],  which  depend  on  the  angle  v,  and 
correspond  to  the  annexed  expression  ; 

a  Su  =  A' f\-,.e. COS. V    [52971.  [52976] 

'a 

We  shall  retain  the  terms  depending  on  the  first  power  of    e,   neglecting  the  higher  powers 

of  this  quantity,  and  the  terms  depending  on     c',   &;c.     The  first  of  the  functions  [4960e],    r5297c-i 

which  containsterms  depending  on  v,  is  [4872],  being  the  development  of        '  ^.cos.(u — v'). 

Now,  in  retaining  only  the  terms  of  the  order   e,  we  obtain  from  [4870A], 

9m'. u'^  9m'.  a4 

m:^  "^  ~  S^Ç^'     ^  •  ^°^-'^^-  [5297rf] 

Moreover,  by  neglecting  terms  of  the   order     mc,    we  have     cos.(t) — v')  =  cos.(t> — mv) 

[4S37].     Multiplying  this  by  the  preceding  expression  [5297(7],  and  retaining  only  the  terms 

depending  on  the  angle     v,   we  get,  in  [4872],  the  expression, 

9m'.  a"! 
-8^1?i"2<^-<=°^-^;  [5297e] 


and,  by  substituting 


_3 

m'.ai         m'.a^  a  ma  nfi    a       r.„^,    ,.„„„,„ 

=  -.  -,     [4S65,5082A'],  [5297e'] 


o^.a'"!  Ui-a!^   a'         «,     a'  a      a 

it  becomes,  by  a  slight  reduction, 


36m9 


a 


—  .  e .  cos.v. 


16a       a'  ■  [5297/-] 

The  second  of  the  functions,  which  must  be  noticed,  is 

3m'.  u'*      du 


.  sin.(î)— t)')     [4SS0] 


8?t2.u5  •  rf«  •  """^        '^>     y^—i'  [5297ff] 

it  was  neglected   in    [4881],  on   account   of  its   smallness,  and   not  inserted  in  [4960e]. 
Substituting  the  values  [4937n,  5297e'],  it  becomes  successively. 


672  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[5299] 


[5297il:] 


[52971] 


(c— l+m).{l— (c— 1+m/— |/rt-| 


3m'.  a""  du    .     ,  3m2     a  du      .     , 

[5297ft]  -  8^;:^  •  «  •  5^-sm.(«-»«r)  =  _—._.„._.  s,n.(«-mr) . 

Now,  by   puttina;     c  =  1,     we    have    in    r4878al  the  term     -— = .  sin.cy.     If 

[5297t]  J     I  o  dv  a 

substitute  this,  in  the  last  expression  [5297A],  it  produces  the  term, 


m-     a 
A  ■  —  .  — , .  e  .  cos.  V. 
^®      a      a' 


Adding  it  to  the  term  [5297/]  we  find,  that  the  sum  becomes 


SSm-î     a 

—  e  .  cos.  V. 


16a      a' 

The  third  of  the  functions,  to  be  noticed  in  [4960c],  is  [4S92].  This  is  found,  as  in 
[4892a],  by  muUiplying  the  sum  of  the  functions  [4855,4889]  by  the  function 
[4890].     If  we  retain  terms  of  the  order   e   only,  we  may  put  the   function  [4890]  equal 

[5297/']      to      -  •     Multiplying  this  by  the  function  [4885],  it  produces  nothing  of  the  proposed  form 
a 

and  order;  so  that  it  is  only  necessary  to  notice  the  terms  arising  fi-om  the    other  function, 

r5297    1     or      ~  X  function  [4S89],     taking  care  to  insert  the  terms   depending   on    c,    which  were 

neglected  in  the  development  of  [4SS9]. 

If  we  substitute,  in  the  first  member  of  [48S9],  the  values  h'^=  a^,  «'  =  «'"'  [4937n], 
we  get,  by  dividing  by     a  , 

[5297n]  ^X  function  [48S9]  =  —  ^^-  .  /  -J  .  sin.  (v-v'). 

Now,  by  retaining  only  the  terms  of  the  first  order  depending  on  e,  wehave,in  [4826,4837], 
rcriyn-r -i  «  =  a~^ .  (l+c.cos.ci))  ;     v' =  Mv — 2me.sin.ct;. 

From  the  first  of  these  equations  we  get  [5297c];  and  from  the  second,  we  deduce  [5297r]; 

which  is  easily  reduced  to  the  form   [52975].      Multiplying    together   the  two  expressions 
[.5897jj]     r5297o,s],  and  then  the  product  by     dv,     retaining  only  the  terms  depending  on     e.  sin.  v, 

we  get  [52970  ; 
[5297g]  «-5  =  a».  (1— 5e.cos.cy); 

[5297r]  sin.(u — v')  =  sin.(i; — m«)-l-2me.sin.cy.cos.(t) — mv)     [60]  Int. 

[5297s]  =  sin.(«— »nt))+'/ne.sin.v+  &c.; 

[5297J]  -  .  s'ln.  («—«')  =  «^  civ.  (ie+me).sin.  v. 


VII.  i.  §  17]  TERMS  OF  THE  FOURTH  ORDER.  573 


C"^>= IL _ i^ ^,         5300] 


The  integral  of  [5297^],  being  substiluted  in  the  second  member  of  [5297n],  it  becomes 
asin  the  second  member  of  [5297»],  which  is  easily  reduced  to  the  form  in  the  third  member, 
by  using  [5297c'], 

K.f        •       r^oof.1  3/«'.a4     (5e+me)  Urn^    a  (10-|-4m) 

-X  function   48891  = .  , cos.v  =  -—  . —, .  e  .  — —; —  .  cos.  v.  r.52Q7ui 

Adding  this  to  the  sum  of  the  terms  in  [5297/],  we  obtain, 

3m^    a  (  ,    ,{lQ+4m)}  Snfi    a  C  21— lie— 7m  ) 

being  the  same  as  the  three  first  tenns,  connected  with     e,     in  [5298/"]. 

The  fourth  of  the   functions  selected  from  [4960e],  is   that  in  [49081inel],  which,  by 
using  [5082A'],  becomes 


"  20 


aou  =  —  —■  A'^^\  —  .  e  .  cos.v     [5297i]  ;  as  in  the  last  term  of  [5298/].        [5297ur] 


The  Jifth  of  these  functions  r49C0e]  is  [4934],  or  rather,  that  part  of  it  which  is 
contained  in  [4931^].  For,  by  combining  the  terms  A',^''"'.  -  .  cos.(w — Jitv)  [493 Inline 31], 
in  its  first  column,  with  — f  e  .  sin.  (2u  —  2otu — ■  cv)  ,  in  its  second  column,  by  the 
method  in  [493  1?j],  using  also     m^    [5082A'],  we  get  the  term, 

■~    a    ■  a'  ■  c'l^m  '         '"  '  ^°^'  '^  '  [5297a:] 

which  is  the  same  as  that  depending  on     ^,'^'     in  [5298/]. 


The  sixth  of  these  functions  [4960e]  is  [4946],  or,  it  is  rather  the  part 

_2 

-—  .  -  .  f  a5u  .  dv  .2  . sin.  (v  —  v'), 

'•«'    «     -^  [5297y] 

which  is  contained  in  [4945  line  2].     Substituting,  for     aSu,     the  term, 

A[^\e.cos.{2v—2mv  —  cv)   [4904  line  2],  '  ri;oo- i 

and  using     v'=  mv  [4837],     also     m^  [5082 A']  ;     it  becomes,  by  noticing  only  the  part 
which  depends  upon  the  angle     v, 

VOL.  HI.  144 


574  THEORY  OF  THE  MOON  ;  [Méc.  Ce). 

[5300]     *  From  these  we  deduce, 


_2  _2 

— ■  .  — .^i".e.   fdv.s'm.iv — mv).cos.{2v — 'imv — cv')  =  — —  .  — ..^'".e.  f  dv  .sln.v 
4a,      a'        ^  "^  ^  ^  8tt,     a'        '  -^ 

15m2    a       „  1 

[5298a]  = ^  .-.^,«.  c — -.cos.v. 

■'  Da      a  c— I-(-m 

This  is  the  same  as  the  term  depending  on     Jl[^      in  [5:298/]. 

The  seventh  of  the  functions,  [4960e]  is  that  in  [4957],  which  is  derived  from  [4950]  or 
[4882],  being  a  term  of  the  function     -  .  f  (—  j  .  '—   [4SSl'j.     This  is  to  be  multiplied 

[52986]    by  tiie  factor     —  -\- u  =  -  ,     nearly  [5297 Z']  ;  to  obtain  the  corresponding  term  of  [4754] 

or  [5298/].      Now,  the  variation  of  [4956]  contains  the  term, 

3m'|ui,       ^  u"^dv 
[52986']  -^ 


f  -^  .sm.iv  —  v')  [495Gd]  ; 


and  by  substituting     h^^^a,,     v!  =  a'   '   [4937n],  it  becomes, 

3m'.  \i-     f  dv        .  ,. 

-J    —  .  sm.  [v  —  v)  . 

[5298c]  2a,.(i<         u^  ^ 

If  we  notice  only  the  first  term  of  the  second  member  of  [5297<]  we   easily  find,  that  the 
term  depending  on     e,     in  the  preceding  expression,  can  be  put  under  the  form, 

3m'.  (J-      /-     ,  ,      ,         .  3m'.,a        -,  1 

fïaQftrfl  •  /  a^dv.he  .  sm.  v  =:  —  r -.  a",  f  e  .  — — —  .  cos.v; 

[S^oaj  2a,.a'4    -^  'ia^.a'*  c—\-\-m 

and,  if  we  reduce  it,  by  means  of  [5297e'],  it  becomes, 

3m3    «a  20,a 

[5298e]  "~  16a  ■  c?  ■  *  ■  c— 1+m 

[5298c']     Multiplying  this    by  the   factor     -    [5298&],  we  get  the  term  of  [5298/"],  depending  on  f*. 

Hence  we  find,  by  adding  together  the  terras  [5297«,m',  a;,  5298»,  c'],  and  connecting  them 

with \-u    [5241i;],  the  following  equation,  for  the  determination  of  this  part  of    m: 

dv" 

[5298/]     "—  rf„2T^    ^  a  "a      1  c-l+m  5  2a        '     a' 

Substituting  in  this,  the  assumed  value  of    au     or     a&u    [52976];  namely, 

[5298^]  «^"  =  -^'-'^  -l-'-  '"'■  "  ' 

we  get,  by  reduction,  the  value  of    A'['^  [5299]. 

1  a' 

*  (2956)     The  differential  of  the  term  of    7U+s  [5298],  being  multiplied  bj    -  =  — 


Vll.iU?.]  TERMS  OF  THE  FOURTH  ORDER.  bib 

^'çs)  = —0,260496  ;  [530 1| 

C'(^'  =  —0,293763.  IJ^soi] 

[5092c],  gives  in     dl     the  following  term,  using  the  abridged  symbol     v     [5297a]; 

I  /         ,   .      \    y^;/(-^  "'  a~.dv 

(It  =  (c— l-f-?n).  C'f\-  .  e  .  — —  .COS.  v.  [5300a] 

Substituting  the  assumed  value  of  C^^  [5300],  we  find,  that  this  expression  of  cit  is 
represented  by  the  function  [5300c],  or  the  numerator  of  the  expression  [5300]  multiplied 

by  the  common  factor     —  •  e  .  — '- — .cos.v  ;     and,  that  this  is  correct,  will   appear  by  the     [53006] 

examination  in  [5300f/ — s]  where  we  shall  find,  that  the  corresponding  part  of  the  value 
of  dt  [5090p],  divided  by  the  same  common  factor  [5300è],  is  accurately  representedby 
the  function  [5300c]  ; 

->=^.U.(5+2m-10,.)-5^1">-|^'.-^^  4'(^^4.3jn^)4-3^(')  A'"^  I       ^'"'  r..nn  , 


[5082.  or  5082?]  X  "^  =   Q'  X  ^"  ;  [5300c'] 


To  prove  this,  we  shall  observe,  that  the  Jirst  of  the  functions  [5090p  line  1]  is 

[5082.or50829]X^=   Q'X  - 

and,  by  retaining  only  the  terms  in  [50827  ''"^  '^J'  it  becomes, 

\  — ^function[4885]— àfunction[4889]— èa.function[4931p]— àa.function[4932a]  i  X  -^  .     [5300cfl 

The  inspection  of  [4885]  shows  that  it  produces  nothing  of  the  proposed  form  and  order 
in  [5300c].     The  next  term  of  [5300rf]  is, 

-|function[4889]X^;  j,3„„^^ 

and,  by  substituting  [5297?<],  it  becomes, 

3m2     a  (5+Qm)      a^.dv 

—,    —         g POS  V  * 

IC    ■  a'        '    c-l-\-m'  ^a,  '  [.5300/] 

and,  if  we  neglect  the  common  factor  [5300i],  it  produces  the  two  first  terms  of  [5300c], 
depending  on  5-\-2m.  In  the  table  [4931^]  we  find  a  term  which  is  produced  by  connecting 

the  term     yi"^'.-.cos.(u — mv),     in  the  first   column,  with     — ;Se.sin.C2u — 2mv — cv),     in 

a  ^  ^  ^  '  [5300g] 

its  second  column.     These  give,  in  the  third  column  of  that  table,  the  term, 

_2 

6  m  1  .,,_,   a 

.  Je  . — .  Ax'K  —■ .  cos.  V. 

a  c — \-\-m  a 


Substituting  this  in  [5300rfj,  and  using  the  value  of    irfi     [5082A'],  it  produces  the  term, 

5 
|m^. — TT"  "^i"''     as  in  the  fourth  term  of  [5300c].  [5300A] 

The    last    of  the    functions  [5300(/]    produces   nothing    of   importance.      The   second  of 


676  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5301"]     Hence  we  obtain,  iit     ni+£,     the  inequality, 


the  functions    [5090/j]  is   [50906];    and,  by   combining   the  term      — 2e.cos.cv,     in 

a         I 

its  first  column,  with  the  term     — fm^--,  •  :; .003.(1; — 7nv),      in   its  second  coUimn,  or 

a      1—m  ' 

[5300i]     [5082s  hne  19],  we  get      'ÔTYZ.'^  ^     connected  with  the  common  factor  [5300è],  as  in  the 
last  term  of  [5300c].     The  third  of  the  functions  [5090;;]  is     — function['1904]X2.— "; 

and, by  substituting  the  value  of  a5u  [5297],  and  neglecting  the  common  factor  [53006], 
[5300&]     '^^  set     —2A'f^     [5300c].     The  fourth  of  the  functions  [5090pj  is  [5090^]  ;  and,  by 

combining  the  term     — 2A\"\-.cos.{v — mv),     in  the  first  column,  with  — Sc.cos.t),  in  the 


[53001]     second  column,  we  get     3^*"',    connected  with    the    factor   [53006],   as  in   the  seventh 
term  of  [5300c].       The    last  of  the  functions  [5090p]  is  [5090i]  ;  and,   if  we  combine 

rcoAn   -1    ^''^«.cos.(2y — 2mv~cv),     in  its  first  column,  with     3Jl[">.-.cos.(v — 7nv),     in  its  second 

[OoUUwi  ]  a 

column,  we  get     §A[^''.A["\     connected  with  the  factor  [53006].     In    like  manner,   the 

combination  of    A[^^K —  .cos.[v — mv),     in  the  first  column,  with  3^',"c.cos.(2i;-27?iu-ct;), 

in  its  second  column,  gives  the  same  term  ^A[^''.j1[^''\  The  sum  of  these  two  terms  is 
3Ai^\A''^''\  as  in  the  eighth  term  of  [5300c].  We  have  yet  to  notice  the  terms  of 
[5081],  or  of  [5300c],  corresponding  to  the  parts  of  the  equation  [4961],  which  are 
contained  in  [5298a,  e'].  These  terms  of  [5081]  may  be  derived,  in  a  very  simple 
^  °'  manner,  from  those  of  [4961],  by  the  same  process  of  derivation  which  is  used  in  computing 
[5032/]  from  [4946/]  ;  namely,  by  dividing  this  last  expression  by     — 2^-'     [5082A: — /]; 

[530Cj)j    or  rather,  by  multiplying  it  by     — ^a  ;     and  annexing  the  common  factor     —^ —    [5081]. 

The  propriety   of  using  this  method  of  derivation   is  manifest  from  the  consideration,  that 
the  first  of  these  terms  [5298a]  is  derived  from  the  function, 

[5300,]  (^.  +u).-  ./[-^)  .  ^„     m  [4943-4945  line  2]; 

and  this  function  is  very  nearly  equal  to, 

1      2       /°/^/Q\      dv 

Moreover,  tlie  second  of  these  terms  [5298e']  is  derived,   as   in  [52986,  Sic],  from  the 
function    [4956  or  4882] ,   which  is  a  part  of  the  function   [4881'],  by  multiplying  it    by 

\-u  =  -,     nearly   [52986]  ;  and  this  last  product  is  evidently  equal  to  the  function 

[53009^],  from  which  the  first  term  is  derived.  On  the  other  hand,  the  corresponding  terms 

of    di    [5300m, t)]  arise  from  the  function      Q^X-j —  [5300c],whosechicf  term, connected 


VII.  i.  >^n.J  TERMS  OF  THE  FOURTH  ORDER.  577 

*  — 8',31.(l+z).sin.(cw — v-\-mv — w).  [5302] 

The  inequality  depending  on  the  argument  v — mv-\-cv-i^  is  easily  obtained 
from  ^  15;  and  it  is  evidently  expressed  by,t 


with    Q,    is 7/T  '  Ifl' J  \d~)  • '^     [50S2m]  ;      and   this    is    evidently   equal  to  the      [5300*] 

product  of  the  function  [5300/-]  by  the  factor  — ia.~ —  ,  as  in  [5300p].    Now,  if  we  multiply 

the  expressions  [5298rt,  e']  by  the  factor     —  \a.  — — ,     they  become,  respectively,    as 

in  [5300«,w]; 

1  hm-    n  1  a^.dv 

+  16    •  7/  ■•^'  "  c-^T^  •  "7^-'°""  [5300„] 

+  l!^.«.e._LOj^.^^.cos...  [5300V] 

16       a'         c  —  {  -\-  m       \/a, 

Dividing  these  by  the  common  factor  [5300i],  we  obtain, 


15m-  1  >/,v  ,  3m^  10  u. 

.Ax\         and  ^ 


[5300w] 


16       c—l+m  IG    '  c— 1+  m   ' 

which  correspond  to  the  fifth  and  third  terms  of  [5300c],  respectively.     Hence  it  appears, 

that  the  value  of  C*'"*    [5300]  agrees  with  the  preceding  calculation.     Substituting,   in 

[5299,5.300],  the  values  [5117,5194,5158,517.3],  also  that  of    f^  =  ;g^   [4320,4948'],     [5300x] 

we  get,  for     Af\     C'f\     nearly  the  same  values  as  in  [5301,5301']. 

*  (2957)     Substituting,  in   [5298],  the  values  of     C"f,     e,  &c.  [5301',  5194,  5221],     rggoa^] 
we  get  nearly  the  same  expression  as  in  [5302]. 

f  (2953)     The    coefficient  [5303]   may  be  computed  in  the  same   manner  as   that  in 
[5298  or  5300]  ;   but  the  change  of  the   divisor  from     c — l-\-m,     which  is  of  the  order 
m,     to     c-j-1 — m,     of  the  order    2,    enables  us  to  neglect,  in  [5303],  all  the  terms  which     [•'>303a] 
appear  in  [5300],  except     ./2<''\     The  term  depending  on     ^','"     is  found   in  the  same 
manner  as  in  [5300Z],  by  combining  the  term 

—  2.<4',"\-  .cos.  {v  — mv), 

in  the  first  column  of  [5090^],  with  the  term     — 3e.cos.cy,     in  its  second  column  ;  which 
gives,  in  the  third  column,  the  corresponding  term  of 

dt  =  3A[^'\  -  .  e  .  —.cos.{v—mv+cv).  ^5303^^ 

.    .    .  1        aS 

Integrating,  and  then  dividing  by  -^ [5092cl,  we  get  the  expression  [53031  ;  and,  by 

n       »/a,  [5303c] 

using  the  values  of    c,     m,     e,     inc.    [5117,  5194, 5221],  it  becomes  as  in  [5304]. 
VOL.  HI.  145 


578  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5303]  l-m  +  c   •  â'  •  ^  •  s'"- («— »'^+^«— ^)  ; 

consequently,  it  is  equal  to 
[5304]  — 5',01 .  (l+i).sin.(«; — mv-\-cv — t^). 


[5304'] 


Torma  of 


fourth 
order. 


[5305] 


[5306] 


By  following  the  same  process,  we  may  determine  the  other  inequalities  of 
the  fourth  order  ;  but,  as  thoy  are  less  than  the  errors  of  our  approximation, 
it  will  be  useless  to  investigate  them  by  the  theory,  unless  Vv'e  wish  to  carry 
on  the  approximation  to  quantities  of  the  fifth  order. 


If  we  collect  together  the  inequalities  of  the  fourth  order,  which  we  have 
just  determined,  they  will  become,* 

+   n%61  .sm.(2v—2mv—2gv+cv+2è—z!)  1 

—  8',ll.sin.(2cr-f2tJ— 2miJ— 2z=)  2 
+ 10',  1 7 .  sin.(2«—  2mvi-cv — c'mv — ^+t^')  3 

pte'                                 +  5%88.sin.(2cv— 2D+2mv+c'm«— 2^— ^')  4 

—  0\2o.sin.(2cv—2vi-2mv — c'mv — 2^+ts')  5 

—  3%'i6.s\n.(2cv+c'mv—2^—Ts')  '  6 
4-  4%50.sin.(2cr— c'wîi'— 2îï+-n')  7 
+  33',38.sin.(4î;— 4?«t)— CD+^)  8 
+  15',46.sin.(4«— 4mu— 2cy+2!=)  9 

—  8',31.(l+0-sin.(cy— ?J+J?ii"— i^)                    '  10 

—  6%01.(l+0.sin.(f — «u'+ci- — ïî).  11 


18.  We  shall  now  consider  the  moon'' s  motion  in  latitude.  We  have  before 
determined  the  tangent  of  the  latitude  s  ;  and,  as  the  expression  of  the 
arc,  by  its  tangent  s,  is  s— ^s-'+|/ —  &c.  [48]  Int.  we  find,  that  the 
latitude  of  the  moon  is  very  nearly  represented  by  the  following  function  ;t 


*  .'2959)     If  we  connect  together  the  quantities  contained  in  [5240,5248,5257,5266, 
[5305o]     5268,5283, 5296,  5302, 5304]  ;  the  sum  becomes  as  in  [5305]. 

[5306a]         I  (2960)     From     s^^y.sm.gv  -{-  &s  [48971],  we   get,  by  neglecting  the  second  and 
higher  powers  of    5s  ;     and  reducing  by  means  of    [1,  2]  Int. 


VII.i.>^18.] 


MOON'S  LATITUDE. 


r.(  1— i7-).sin. (gv—ù')+6s.  1 1  —jr7~+i7-'Cos.(2gv—2))  \  +-^^f.sin.(3gv—3é)  ; 

from  which,  by  using  the  preceding  value  of  y    [5117],  we  get  the  latitude, 
as  in  the  following  expression;* 


679 

[5307] 


18542',79.sin.(5«— !)) 
+   12',56.sin.(3^«— 3j) 
+525\23.s\n.(2v—2mv—gv+û) 
+      P,14.sin.(2f — 2mv-Jrgv—ô) 

—  5\59.sin.(gv-\-cv — ù — zs) 
1+  19%85.sin.(^i" — cw— ^+to) 
1+     6'4,6.sm.(2v—2}nv—gv-ircv+ê — ra) 

Moon's  Latitude  =  /  "     V,39.shi.{2v—2mv+gv—cv—S+^) 
\ —  2]%60.s'n\.(2v-r-2mv—gv—cv-rù-{-z!) 
+  24>%35.sin.(gv-'rcmv — i — z^') 
' —  25',94.sin.(^« — c'mv — ^+ra') 

—  10%20.sin.(2v—2mv—gv-irc'mv+ô — ro') 
+    22',42.sin.(2y — 2mv^gv—c''mv+ù+i!i') 


+   21%4,0.s'm.(2cv—gv—2-a+ù) 
i+     5',13.sin.(2cw4-^« — 2v+2'mv- 


.—2z!—ù)  I 


1 

2 
3 

"'4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
16 


Moon's 
lattludo. 


[5308] 


[53066] 


— ^s^  =  — ^y^.  s'm.^gv  — Ss.y-.  sin.-^u 

The  sum  of  the  two  expressions  [5306a,  J],  is  easily  reduced  to  the  form, 

s  —  153^7.(1  —iy'^).sm.gv+ôs.{i  —  ^y~-\-i7-.cos.2gv\-}-j'2-y^.sm.dgv.  [53V6C] 

Substituting  this  in  the  expression  of  the  arc  [530G],  and  neglecting  the  terms  of  a  higher 
order,  it  becomes  as  in  [5307].  We  may  remark,  that  the  term  5s.^7^.cos.2gv  [5306c], 
produces,  by  means  of  the  term  [4897  line  1],  the  expression 

i  J?',"'  7^.  COS.  2gv  .  sin.  (9u  —  2mv  —  gv)  ; 

from  which  we  obtain  the  term  lB[''\7^.s\n.{2v — 2mv-\-gv) ,  which  is  of  the  same  form 
as  that  which  is  retained  in  [4897  hne  2]  ;  hence  the  expression  of  the  latitude  [5o06c] 
becomes,  very  nearly, 

7.(1  -  if).sm.gv+.^\y^.sm.3gv-{-lB['>\7^.  sin.(2«— 2mD+^D)-|-(l— Jys).^,. 

*  (2961)     Substituting  in  [5o06e],  the  expression  of    5s     [4897],  and  then  the  values 


[5306d] 


[5306«] 


580  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[5309]      —  =  —  ,     D    being  the  eartli's  radius.*     Considering    the  smallness 


19.     It  now  remains  to  determine  the  third  co-ordinate  of  the  moon,  or  its 

parallax.     The   sine  of  the  moon's  horizontal  parallax  is  represented  by 

D  Du 

of  this  sine,  we  may  take  it  for  the   expression  of  the   parallax  itself  ;    and, 
if  we  substitute  the  value  of    u     [53096]  ;  naraelj, 

[5310]  «  =  1  .  {l+e''+l7''+e.(l+e'').cos.(cv—z^)—l7''.cos.(2gv—2ù)}-\-èu  ; 

neglecting    terms   of    the   order     —  .  e"* ,      we  shall  find,  that  this  parallax 


Motll'rt 

purallax. 


a 
is  represented  by  the  folloicing  formula. 


[5311]      -=  -^^=- .  (1  +e'^).  1 1  +e.n-l7''+iy^cos.(2gv-2})].cos(cv--^)-{-a&u-s6s  I . 
r       \/  \-\-ss        a    ^  '  U41/  vo  /j\ 

[5307o]     of  B^°\...B['^^    [5176  —  5191],  also    those    of    m,  e,  &,c.     [5117,5194,5221],   we    get 
[5308],  nearly  ;  a  few  of  the  small  terms  being  neglected. 

*  (2962)    If  we  substitute  the  value  of    r    [4776],  in  the  well  known  expression  of  the 

[5309o]     «me  of    the   horizontal  parallax     -,     it  becomes  as  in  [5309],  or  as  in  the  first  member  of 

[5309/],  and  this  may  be  taken  for  the  parallax  itself,  by  neglecting  its  third  power.  Now, 
if  we  add  to  the  expression  of  u  [4826]  ,  the  part  of  <5u,  [4904,  &c.] ,  arising  from  the 
perturbations,  it  becomes,  by  neglecting  terms  of  the  fourth  order, 

[53096]  u  =.  ^  .  j  l-\-e^-\-t/+e.{l  +  e'').cos.cv—iy~cos.2gv+a5u  j    as  in  [5310] 

[5309c]  =^.(\+e~)-\l-\-{7--{l—cos.'2gv)+e.cos.cv+a<')u]^. 

Developing  the  radical  \/l+W ,  neglecting  s"  ,  and  substituting  for  s,  its  value 
[5306a],  we  get, 

[5309<i]  77^n^=  l—i^=  1  -i.  j7=.sin.V+2^«-r-S'"-5-^^ 

=  1  — iy-.(l — C0S.2i^u) — ds.y.s'in.gv  . 

Multiplying  together  the  expressions  [5o09c,e],  and  the  product  by  D,  we  get,  by 
neglecting     7^,  &.c.  of  the  fourth  order. 


[5309e] 


[5309/]  —^ .(l4-e-).{  l+c.(l— iy+if.cos.2^«).cos.ra+a5M— <55.7.sin.g«|. 

Y  l-\-ss  a 

This  becomes  as  in  [5311],  by  substituting,  in  its  last  term,  the  approximate  value  of 

[5309^]  y.sin.g-D  =  s.  [5306a]. 


VII.  14 19.]  MOON'S  PARALLAX.  581 

To  determine     —,     we  shall  observe,  that  we  have,  in  [4968],* 
a 

^-  =  -.  0,9973020  ;  [53i2] 

a         a, 


and,  by  [5082,  5090], t 


Hence  we  get,î 


-^  X  1 ,0003084  =.  - .  [5313] 


l^  é  ^  /n^.  (  1 ,0003084)2 
a  Y  0,9973020" 


[5314] 


Let     2  s     be  twice  the  space  which   the  earth's  attraction   would   make    a      .^gj^ 
particle  describe  in  the  time     t ,     in  the  parallel,  on  which  the  square  of  the 

3T 

sine  of  the   latitude   is     i.     This  attraction  is     —       [1812,  1811/],^   the      [5316] 

earth     M    being  supposed  elliptical.     But  we  have  before  put     M-\-m  =  1      [5317] 
[4775"]  ;    m    being  here  the  moon's  mass  ;    therefore,  we  have, 

~  (iVi+»z).X)2  •  [^318] 


a  2 

*  (-2963)     Substituting,  in     m  [5094],  the  value  of  m  [5117],  we  get  m=0,0055796. 

With  this,  and  the  values  of    e',     m,     y,    A'i\    B?"     [5117,  5157, 5176],  we  find,  that    t^^^^"] 

the  equation  [4963]  becomes  nearly  as  in  [5312]. 

t  (2961)     If  we  substitute,  in  the  coefficient  of    — — ■   [5082],  the  values  of  w,  A'-^\ 
A[^\  e  [5117,5157,5158,5194],  it  becomes     i^^.l, 0003084.  This  is  to  be  put  equal     [5313a] 

y  (If 

dv 
to    —  [5090];  hence  we  get  [5313]. 

t(2965)     We  have,  in  [5312],      J-    =    ~  ■  ^=m-   ;      multiplying    this    by 

a'. 1,0003084,     and  substituting,  for  the  first  member  of  this  product,  its  value  -  [5313],     ^5314^1 

1  3     1,0003084  ,  .,     ,    ,         r  , 

we  eet    —  =  a-.    ,  — ^==^  ;     whence  we  easily  deduce  [53141. 
^       n  v/0,9973020  J'  L  J 

%  (29G6)     Changing    z    into    s,    in  [67],  we  get     2s  =^^2;     g     being  the  force  of    [5316a] 
gravity    [54"  line?].     Now,  in  the    parallel  of  latitude,  mentioned   in   [5315],  we    have 

VOL.  in.  146 


582  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Hence  we  deduce,* 

[5319]  ^  =  \    /    -^^        £)      "'^'      (1,0003084)^ 

«  V       M-\-m  '  'as     *       0,9973020 

If  we  suppose     t     to  be  equal  to  a  centesimal  second,  and     T     equal  to  the 
number  of  centesimal  seconds  of  time,  during  a  sidéral  revolution  of  the  moon, 

[5331]     we  shall  have  t     »»^  =  ™  ?     "^     being  the  ratio  of  the  semi-circumference  to 

the  radius.  If  /  be  the  length  of  a  pendulum,  vibrating  in  a  centesimal 
'•^  ■'  second  of  time,  upon  the  parallel  under  consideration,  we  shall  have,  as  in 
[5323]      [86'],     2;=:^^/,t     which  gives, 


M 

^2 — ^=0     [1618'"];  Iience  the   expression  of     V    [1812],  becomes     V=—,     M 

being  the  mass  of  the  ellipsoidal  earth,  and    r     the  distance  of  the  attracted  point  from  its 
centre,  [1G16',  1016"'"].   Now,  the  attraction  of  the  earth,  in  the  direction  r,  is  represented 

r5316c]     by    — ( —  ^i  :^  —      [181  iZ, 53166]  ;  and,  by  changing     r     into     D,     to  conform  to  the 

M 

present  notation  [5309],  it  gives  very  nearly,  the  expression  of  the  gravity  g  =  jp.  [531C]; 

M  l~ 
[5316d]    hence  [531Ca]  becomes     2j  =  -p- .     We  have  put,  in  [4775"],     Jll-\-m     equal  to  unity, 

M 

,,„.,,     therefore,  for  the  sake  of  homogeneity,  we  may  change  M  into     ~ — ,  in  the  preceding 
[5310e]  °  •'  M-\-n  ^  ° 

expression  of     2; ,     and  then  it  becomes  as  in  [5318]. 

*  (2967).  Multiplying  [5318]  by     —  ,     and  extractmg  the  cube  root,  we  get, 


the  product  of  this,  by  the  expression  [5314],  gives  [5319]. 

t  (2968)     Noticing  only  the  mean  motions,  we  have  nt  =  v  [5220].     Now,  when     v 

|.ggç,j  ,    is    equal    to     2t  ,     t     becomes     T     [5320],    and    we    get     ?«  T=  2ir,     or    7i  ==  ~  ; 
whose  square  gives     n^     [5321]. 

J  (2969)     Changing,  in  the  formula  [86'],    z    into    e,    and     r     into     I,     to  conform 

4 
to  the  present  notation,  we  get    2s  ^t^;      as   in    [53331.     Multi;)lyina;   it  by      ,-77^.  we 
[5323a]  L  J  I  J     o         J      ijo 

obtain     J^2=:^;    hence     ir=-~      [5321];    and,  as      <=1,       [5320],    we    have 

—  =  A  ;  substituting  this  in  [5319]   and   putting   4.(1,0003084)2=  (2,0006168)2,  we 
get  [5324]. 


VII.  i.  §  19.]  MOON'S  PARALLAX  ;  583 


D  _  .^   /   M       D    (2,0004108)2 


.W+m      /     ■    0,9973020.T2  [52,14.] 

The  length  of  a  pendulum,  vibrating  in  a  centesimal  second,  upon  the  same 

parallel,  is  equal  to   0™^'-,740905  [2054],*  we  must  increase  it  by  its  434th  ^^^^^ 
part,  to  obtain  the  length  which  could  obtain  independently  of  the  centrifugal 

force  ;  hence  we  have,     /  =  0"""-,742612.     The  value  of    D     is  equal  to  [532G] 

6369374"'"-  [3896,  nearly]  ;  lastly,  we  have,  by  the  phenomena  of  the  tides,  [5327] 

m=  —:, —   [4321];   and,  by  observation,    T  =  2732 166  centesimal  seconds;  [5328] 

hence  Ave  have,t 

■?-  =  0,01655101.  f5329] 

Estimating  in  seconds  the  coefficient     —  .(1+e^),     we  find  it   equal  to      [5330] 

3424",  16.     This  being  premised,  we  find,  for  the  expression   of   the   moon's 
parallax,  in  the  proposed  parallel  ;  X 


*  (2970)    This  value  corresponds  with  the  formula  [2054],  putting  sin.-Nj^  =sin.^]at.=^ 
as  in  [531 G].     This  must  be   increased  ^j^j  part,  to  correct  for  the  centrifugal  force  [088"], 


by  which  means  it  becomes     /  =  0'"='-,742612,    as  in  [5326].     This  will  be  varied  a  Title 
if  we  use  the  corrected  value  of    /     [2054w,or205Cp]. 


[53256] 


t  (2971)  Substituting,  in  [5324],  the  values  of  I,  m,  D,  T,  [5326  -5328],  we 
get  [5329],  nearly.  Multiplying  this  by  1-f-ec  [5194],  and  then  by  the  radius  in 
seconds,  we  get  the  expression  [5330],  nearly.      This  would  be  varied  a  little  by  correcting  •' 

the  value  of    /,   as  in  [o325J],  and  also  by  the  change  in  the  value  of    m  [11906, 3380i]. 

f  (2972)   Substituting  the  value  of  -  .  (l+fc)  =  3424^16  [5330]  in  [5311],  it  becomes     r533Q„i 
Moon's  Parallax  =  3424%1G.{  l-\-e.{l—ly^-\-^-)'^.cos.2gv).cos.cv-\-aSu — sSs\.  [53306] 

We  may  substitute  in  this     }y^e.cos.2gv.cos.cv  =  ^j'^e.cos.{2gv — cv),     neglecting  the  term     [53301 
depending  on  the  angle     2gv-\-cv,     because  the  term  is  small  ;  and  angles  of  this  form  are 
not    retained    in    [5331].      Moreover,   the    chief    term    of     Ss     [5308  line 3,  or 5307]  is 
à25',23.sm.{2v—2mv—gv);     and  the  chief  term  of    s     [5307]  is  [5330rf] 

7.(1  — 17^).  sin. ^11  =  0,0899.  sin.  ^t)     [5117line5].  [5330^] 

Multiplying  these  two  expressions  together,  we  get,  in     sSs  ,     the  terms, 

2S\6.\cos.{2gv  —  2v+2mv)—cos.{2v—2mv)\  ;  [ssscn 

substituting    this  in  [53303],  and  dividing  by    the  radius  in  seconds    2062C5',   it  produces 
the  terms    0',39.  j— cos.(2^i'— 2y-{-2my)-f-cos.(2i; — ^mv)\.     Hence,  [523 Oi]  becomes, 


584 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


Parallai. 


[5331]      Moon's  Parallax  = 


3424% 16                                               V 

1 

+  187%48.cos.(ct)— z^)                             \ 

2 

+ 

24>%6d.cos.(2v—2mv) 

3 

+ 

38%07 .  COS.  (2v—2inv—cv+-^) 

4 

— 

0^70 .  cos.(2îJ — 2mv-{-cv—^) 

5 

0',17.cos.(2î;     2mv+c'mv     ra') 

6 

+ 

1%64.  cos.(2t> — 2mv — cWi+w') 

7 

0^33.  cos.  (c'm«—^') 

8 

0',22 .  cos.{2v-2mv-cv-{-c'mv+^-^') 

9 

+ 

P,63 .  cos.{2v-2mv-cv-c'mv+-^+-^) 

10 

0%65  .COS.  (cv-\-cmv — « — to') 

11 

+ 

0'',87 .  cos.(cD— c'my— w+to') 

12 

+ 

0%01.cos(2cw— 2^) 

13 

+ 

3^60 .  cos .  (2cî;— 2tJ+2  mv—2z,) 

).                    14 

+ 

0^07.  cos.  (2^t;— 20)                         / 

15 

0',1 7 .  COS.  (2gv—2v+2mv—2ô) 

16 

0%0l.cos.(2c'mv—2-m') 

17 

(y,9o.cos.(2gv     CV     2S+r,) 
0',06 .  cos.(2v-2mv-2gv  +  cv+2s-^) 

18 

19 

0%97.(l+i).cos.(v—mv) 

20 

+ 

O'J  6 .  (1  -|-«).cos.(z7 — mv-\-c'mv-y:') 

21 

0%04.cos(2«-2miJ+c«;-c'mw-TO+TO') 

22 

— 

0',  1 5 .  COS.  (4>v — 4m«j — cv+:^) 

23 

+ 

0',05 .  COS  (4^—Amv — 2cz;-f  2si) 

24 

+ 

0',  1 3 .  cos(2ce;-2t)+2w«+c'mz;-2a-TO') 

25 

+ 

0%02.  cos.(2cu+2«— 2mzj— 2^) 

26 

0%\2.(l+i).cos.(cv—v+mv     -)   , 

27 

[5330âr] 


Moon's  Parallax  =  3424%16.p+e.(l—iy2).cos.ct)4-^72e.cos.(2^D—CT)+a(5M} 

—  0^39  .COS.  (2gv—2v-\-2mv)-\-0\  39.cos.  {2v—2mv). 

We  must  now  substitute  the  value  of    aSu     [4904,5242,5251,5258,5269,  5287, 5297, Sic], 
also  [5117,5157—5175,5221],  and  we  shall  get  [5331]. 


VII.ii§20.]         EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  585 


CHAPTER   II. 

ON  THE  LUNAR  INEaUALlTIES  ARISING  FROM  THE  OBLATENESS  OF  THE  EARTH  AND  MOON. 

20.  We  shall  now  consider  the  terms  arising  from  the  oblateness  of  the 
earth  and  moon.*  We  have  seen,  in  [4773],  that  the  effect  of  this  oblateness 
is  to  add  to  the  expression  of     Q     [4756]  the  quantity, 

(  ôV    ôV  ) 
(M+m).  <  —H ^  =  increment  of  Q.  '  [5332] 

If  we  put, 

oLp  =:  the  ellipticity  of  the  earth  ;  [53331 

a;p  ;=   the  ratio  of  the  centrifugal  force  to  the  gravity  at  the  equator  ;        [5333'] 

D  =  the  mean  radius  of  the  earth  ;  [5334] 

(*   =  the  sine  of  the  moon's  declination  ;  [5334'] 
we  shall  have,  as  in  [1812],t 


*  (29T3)  This  subject  is  tieated  of,  in  a  more  simple  and  elegant  manner,  in  the 
appendix  to  this  volume  [5937 — 5971]  ;  and  again,  in  the  fifth  volume  [12952 — 12996]; 
where  some  very  small  terms  are  noticed,  which  are  neglected  in  this  volume  ;  but  they  " 

have  but  little  effect  on  the  resulting  formulas.     We   shall,  in  the  notes  on  this  chapter, 
restrict  ourselves  to  the  terms  here  investigated  by  the  author,  and  shall  follow  the  same     ^  ' 

method  of  demonstration  which  he  has  used. 

t  (2974)    We  have,  in  [1812],  for  an  ellipsoid  of  revolution, 

r  =  f+(4.,-./o.i.itf.K-4).  ,,^, 

VOL.  III.  147 


586  THEORY  OF  THE  MOON;  [Méc.  Cél. 

[5:135]  F  =:   ^  +  I  lap— a,,  |  .  ^.  M.(^.2— X). 

If  the  earth  vary  from  the  elliptical  form,  Ave  shall  have,  by  §  32,  35,  of 
book  iii.,* 

[5336]  r  =   ^'  +   ^  (ia,?_ap).CaS— a)+a/t'.  (1— ,x2).COS.2^  |  .  M.  ~   ; 

[5337]      ap  and  0-h'  being  constant  quantities,  depending  on  the  figure  of  the  terrestrial 

[5338]      spheroid;  and  ■^  the  angle  formed  by  one  of  the  two  principal  axes  of  the  earth, 

situated  in  the  plane  of  the  equator,  with  the   terrestrial   meridian,  passing 

through  the  moonh  centre  [1746'].     It  is  evident,  by  the  following  analysis, 


[53356]     To  conform  to  the   present  notation,  we  must  put     tt/(=  ap     [1795',  5333]  ;  and,  in  the 

1  2)2 

[5335c]     second  term,  we  must  change  -  into   -^,   to  render  it  homogeneous  with  the  first  term  : 

observing,  that  the   radius  of  the  earth     D     [5334],  is  supposed  to   be  nearly  equal  to 
unity  in  [1795",  1812].     Making  these  changes  in  [5335a],  it  becomes  as  in  [5335]. 

*  (2975)     Neglecting  the  attraction  of  foreign  bodies,  and  the  terms  depending  on    r"'^, 
in  [1811],  we  get,  for  an  ellipsoid  of  a  general  form, 

[533(V,]  V^f^  ./„\o  .  d.a-+^^.  r(^>./„'p.rf.«^- "3  .  Z^-\ 

To  render  this  homogeneous,  we  must  multiply  the  two  last  terms  by     D^,    as  in   [5335c], 
and  substitute,  for    ^itf^^.d.a^,    its  value  M  [1811',  4757]  ;  by  which  means  it  becomes, 

[5336c]  F  =  f  +  J  a  Y^^>  -|  .Z^^^  \.M.  ^'. 

If  we  substitute  this  value  of    M,     in     aZ<-'     [1793],  we  get, 


[53366] 


[5336c']  _^.Z«)=ia9.(,2_A); 

and,  from  [1763],  we  have,  by  changing     a/i     into     ap,    as  in  [5335i],  also    h""  into  A', 
to  conform  to  the  present  notation, 

[5336c/]  ^''''  =  _p.(,.3_J)+A'.(l-^^).cos.2«  ; 

r5336el     the  earth  being  supposed  to  revolve  about  one  of  its  principal  axes  [1 762',  &c.].  Substituting 
these    in  [5336c],  it  becomes  as  in    [5336].     The  radius  of  an  ellipsoid  is  represented  by 
[5336/]    j_j_y^y(n,     [-1775^01.15030]  ;  and,  if  we  substitute  the  value  of     Y^-'^     [5336^/],  we  get, 

„  ,  1 — ap.((J.~ — ^-)-|-aA'.(l — fj,~).cos.25i  =  radius  of  the  spheroid. 

[5336A]    At  the  pole,  where     fx=lj     this  becomes     1— jap;     subtracting  this  from  [5336^-],  and 


Vll.ii.  §20.]    EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH. 


687 


that  the  term  depending  on  cos.2ro  has  no  sensible  influence  on  the 
lunar  motions  on  account  ol'  the  rapidity  with  which  the  angle  w  varies; 
so  that  the  value  of  V,  which  we  shall  here  use,  is  the  same  as  in  the 
elliptical  hypothesis,  with  an  ellipticity  equal  to  ap  ;  but,  in  the  general 
case  of  any  spheroid  whatever,  ap  does  not  express  the  dlipticiiy  [53o6/i;]. 
We  may,  therefore,  suppose,  in  this  general  case,  that  the  value  of  Q  [4756] 
is  increased,  on  account  of  the  oblateness  of  the  earth,  by  the  function, 

(|aç  —  f-p).  — .((J.2 — -i)  =  increment  of  Q  [4756]; 

M^m    being  taken  for  the  unity  of  mass  [4775",  5336/]. 

We  shall,  in  the  first  place,  consider  the  variation  of  the  orbit,  or  the  moon's 
motion  in  latitude,  depending  on  this  cause.  If  we  put  >-  for  the  obliquity 
of  the  ecliptic  to  the  equator,  and  fix  the  origin  of  the  angle  v  in  the  vernal 
ecjuinox,  at  a  given  epoch  ;  tee  shall  have,  very  nearly,'*' 


[5338'J 
[5339] 

[5339'] 

[5340] 
[5340'] 

[5341] 
[5342] 
[5343] 


putting    ;j.  =  0,     we  get  the  excess  of  tlie  equatorial  radius,  or, 

the  ellipticity  =  ap-)-aA.cos.2^.  [5336i] 

Hence  it  appears,  that   the  ellipticity  of  the  different  meridians  varies,  with  the  different     ,roqcA.| 
values  of    2^,     from     ap — a//    to     af-f-aA  ;     instead  of  heing  generally  represented  by 
ap,     as  in  [5333,5339'].     From   [4767,5336]  we  get     &V,    and  then  the  first  term  of    [5336/] 
[533-2]  becomes  as  in  [5340,5340']. 


*  (2976)  In  the  annexed  figure,  P  is  the  pole 
of  the  moveable  equator  ;  P'  the  pole  of  the  ecliptic  ; 
M  the  place  of  the  moon  ;  so  that,  if  the  moon's 
latitude  be  represented  by  /,  and  the  declination  by  ^ 
d,  we  shall  have  PM=9Q-'—d;  P'M=  90''— I; ^^ 
PP'=>.;  PP'M=  90"— fv  [5345].  Substituting 
these  symbols  in  the  formula  [5344f],  which  is  the  same 
as  [1315®],  we  get  [5344r/],  using  the  symbol  /j-  =  sin.c? 
[5-334'].  This  is  reduced  to  the  form  [5344e],  by  means 
of  the  expressions  of    sin./,     and     cos./     [47T6i]  ; 

cos.PM  =  sm.P'P.sm.P'M.cos.PP'M+cos.P'P.cos.P'M  ; 
/J.  =sin.X.cos./.sin.yi)-{-cos.X.sin./; 
1 


J'oie  o/Eriuator 


Mo  un. 


fA=  sm.X. 


v/l+ss 


.sin./i!-(-cos.X, 


VÎ+S 


[5344a] 
[.53446] 

[5344i'J 

[5.344c] 
[5344(/] 

[5344e] 


588  THEORY  OF  THE  MOON;  [Méc.  Cél. 

L5344]  ft  =  sin.x.y^i — ss  .sin.fv-\-s  .cosA; 

[5345]  J'y  being  the  apparent  longitude  of  the  moon,  referred  to  the  moveable  vernal 
equinox.  We  must,  therefore,  add  to  the  value  of  Q  a  quantity,  which  we 
shall  represent  by,* 

Terms  of 

[5346]     Q=  ih'^v — ap).— .{sin.-x.(l  —  5^).sin.y«-J-2s.sin.x.cos.x.sin/t)-}-s^.cos.-^ — i}. 

This  being  premised,  we  shall  resume  the  equation  [4755].  We  have 
developed,  in  [5018 — 5049],  the  different  terms  of  this  equation,  depending 
on  the  sun's  action.  It  is  evident,  that  the  preceding  function  adds  to  the 
equation  [4755]  the  following  quantity, f 

[5347]  2.(ap  —  lo-cp).      ^  ■  .sin.x. COS. X. sin./y+ (g^ — \).H.smfv  ; 


[5344/] 


[5346o] 


[53466] 


If  we  neglect  the  third  and  higher  powers  of    s,     we  may  change        ,  into  \/l—s^, 

and      , ^   into   s  ;     by  which  means,  the  formula  [5344e]  becomes  as  in  [5344]. 

*  (2977)     Substituting    (a    [5344]    in  [5340],     and   putting     2  s,     for    2s.^rT^,     in 

1  u 

the  coefficient   of    sin./t;,     we  get  [5346].     Now,  we   have     —  =     ,  [4776], 

which  is  nearly  equal  to     ?<.\/l  —  s~',     substituting  this   in   [5346],  neglecting     s^,     &ic. , 
we  get,  for  this  part  of     Q,     the  following  expression  ; 

Q=(i[i,:p — a.'i).D^.u^.  ?  sin.-X.(l  —  s-)-.sin.^/i;-(-24-.sin.X.cos.X.sin.yD-)-s^.cos^X — ■j(l-«^)-  \ . 


t  (2978)  The  substitution  of  the  value  of  Q  [534G6],  in  [4755],  produces  an 
[5347al    equation  of  the  same  kind  as  [5037]  ,    in  which     r     is  composed  of  a  series  of  terms,  of 

the  form  k,.  s'm. (i^t-^-s^),  depending  on  Q.  When  i^  is  very  nearly  equal  to  unity, 
r5347il    ^^^'^  corresponding   term  of    s     will  be  very  ir.uch  increased  by  the  divisors  introduced  by 

the  integration  ;  as  in  the  similar  case  of  the  equation  treated  of  in  [4849],  as  will  be  seen  in 
r5347cl    [5347r — t'].    Now,  /—I  is  of  the  order  aiiyVocj  [53475']  ;  therefore,  the  term  depending  on 

sin./i'     must  be  particularly  noticed  ;    and,  in  fact,  it  is  the  only  one  the  author  considers 

as  necessary  to  retain  in  this  calculation.     In  making  the  substitution  of  the  value  of     Q 

[53466],  in  [4755],  we  may  neglect  the  quantities     (-j^))      ("/")'     because    they  are 

ds 
r5347el    multiplied    by     s,     or     —,     of  the  order     y.sm.gv,     or     y.cos.gv,     and  produce  only 

terms  of  small  value,  in  which     i,     differs  considerably  from  unity.     We  may  also  neglect 


Vll.ii.  ^5-20.]        EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  589 

supposing    the    inequality  of    6s,     depending    on    the   angle    fv,     to    be      [5347] 


the  term •(  — I     [47551,  because  it  is  multiplied  by     s^.     Hence  the  equation 

h-.u^    \ds  J  -^  ^ 

[4755]  becomes, 

^        dels  ,  1  /dQ\ 


dds  , 


Now,  by  noticing  only  the  terms  depending  on     sm.fv,     we  get,  from  [5346i], 
(-^]  =  2.(|aç)— ap).DV.sin.X.cos.X.sin./y. 

Substituting  this  in  [5347/],  it  produces  the  term, 

1      A/Q\         ^  ,         ,      ,  />2«   . 
""  hA^^'  \di)  "^  -•("-'— JM--^  sm.X.cos.X.sin/t.  ; 

which  is  the  same  ns  the  first  term  of  [5347],  or  the  first  term  of  the  function  r  [50371. 
The  other  term  of  r  is  deduced  from  [5040 line  1],  iWi.-.5s  ,  by  the  successive 
substitution  of  [5082/t',4828e]  ;  by  which  means,  it  becomes, 

§  m^.  Ss  =  (g- — 1  )  .OS,     nearly  ; 
and,  if  we  use  the  value  of    Ss     [5348],  it  produces     (g^ — l).JZ.sin./j;,     as  in  the  last 
term  of  [5347].     Hence,  the  equation  [5347/],  by  retaining  only  the  terms  depending  on 
the  angle    fv,     is  reduced  to  the  following  form  ; 

=  ^a+*+2-l"-P— io-?.).— .sm.X.cos.X.sin./y4-(n-2_l).7i.sin./«. 

Substituting  the  assumed  value  of  'U ,  or  s  =  H. sm.fv  [5348],  and  dividing  by 
sm.fv,    we  get, 

0  =  (— /^+l)-ff+2.(ap~ia?).-^\sin.X.cos.X+(^2— l).if. 
Connecting  together  the  terms  depending  on     H,     and  dividing  by  its  coefficient,  we  get, 

-"^ ^:Zf2 -^-sm.X.cos.X. 

The  moon's  longitude  v,  is  counted  from  tlie  fjced  axis  x,  or  the  fxed  vernal 
equinox  [4760']  ;  and  fv  [534-5]  is  the  same  longitude,  counted  from  the  moveable 
vernal  equinox  ;  hence,  /—I  is  of  the  same  order  as  the  ratio  of  the  precession  of  the 
equinoxes  to  the  moon's  mean  motion.  Now,  the  annual  precession  is  nearly  50'  [4614],  and 
the  moon's  annual  motion  is  —-=4813'',  nearly  [5117,  5I17«].  These  quantities 
are  to  each  other  in  the  ratio  of  1  to  340000,  nearly  ;  hence,  /—I  is  of  the  order 
WcTTir;  which  is  very  small,  in  comparison  with  g-— 1  =  fm^ :=  ^i^,  nearly  [5I171ine3]; 
VOL.  III.  148 


[5347/] 

[53i7g] 
[5347A] 

[5347.] 

[5347A;] 
[[5347/] 

[5347m] 

[5347rt] 

[5347n'] 
[5347o] 

[5347pJ 
[5347?] 


590  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

represented  by, 


[5348] 


6s  =  H.s'm.fv. 


We  may,  moreover,   easily   satisfy  ourselves,  that  this  quantity  is  the  only 
sensible  one  which  results  from  the  function     Q     [5346].     Adding  it  to  the 
differential  equation  [5049],  and  observing,  that    /—I     is  extremely  small, 
[5349]      in  comparison  with     g — 1,     we  get,  by  integration, 

^^       — 2.(ap— iaqj)  ■    D'^       . 

[5350]  H=  h — r —   •  -^-  sm.x.cos.x. 

g^ — 1  a- 

Hence  we  obtain  in    5 ,    or  in  the  moon's  motion  in  latitude,  the  inequality,* 


[5351] 
[5351' 


Is  =  —  — ^.  — r.  sm.x.cos.x.sm.ji'. 


Which  is  the  only  sensible  inequality  of  the  moon'' s  motion  in  latitude,  arising 

from  the  ohlateness  of  the  earth.     This  inequality  is  equivalent  to  the  supposition 

that  the  moon's  orbit,  instead  of  moving   on  the  plane  of  the  ecliptic,  ivith  a 

[53521      constant  inclination,  moves,  ivith  the  same  condition,  upon  a  plane  passing  ahmys 

through  the  equinoxes,  beticeen  the  equator  and  the  ecliptic,  and  inclined  to  this 


[5347g']     so  that  we  may  put    /=!,    in  [5341n'],  and  we  shall  get, 

_2.(ap-^a9)    D^u 

H  = V— ; •  — To—  •  sin.X  .  cos.X. 

[5347J-]  jg-  —  I  /* 

Substituting;    u  =  -,     h^z=a,  =  a,      [4937n,  5312],    it    becomes    as  in  [5350].      We 
[5347«]  a 

may  observe,  that  if  /  differ  considerably  from  unity,  it  will  make  the  corresponding 
value  of  H,  deduced  from  [5347n'],  very  small;  because  the  divisor,  in  finding 
JH,  will  be  a  large  number  of  the  order  g^ — /^,  instead  of  the  very  small  one 
of   the    order    g- —  1     [5347r]  ;     and,   for   this    reason,   most   of  these  terms     of     Q 

may  be  neglected,  considering  that  they  are  multiplied  by  the  very  small  factor  (o-r-aU-?)-"",  ; 

which  can  become  sensible  only  by  means  of  a  small  divisor. 


[5347/] 


*  (2979)     We    have     g^—\={g-\-l).{g  —  l)=2.{g—l),     nearly    [4828e], 
[5351a]     substituting  this  in  [5350],  and  then  the  resulting  value  in     ôs=H.sm.fv     [5348],  we 
get  [5351]. 


VII.  ii.  '^  20]        EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH. 


591 


last  plane,  by  an  angle,  loJiich  may  be  represented  as  follows,* 

(ap-4a(p)      1)3        .  ,  [5353] 

Angle  of  inclin.  of  the  equator  and  fixed  plane  =  ' '—-^  .  -^  .  sm.x.cos.x.    ]^:^'S-,^, 

°  '■  g 1  «  equator  to 

the  fixed 

We  have  found  in  [5329,  5117], 

-=0,01655101;         ^—1=0,00402175;  ^5354] 

a 

also  at  the  epoch,  in  1750, 

X  =  23''  28'"  17%9     [4353"].  ^5355] 

Lastly,   019  =  ^1^    [1594«,&c.];  therefore,  by  supposing    <^p  =  ^i^-    [2034]      [5356] 
the  preceding  inequality  becomes, f 


j\'l[  Moon 


77 

\ 

[53520] 

J? 

3^-— - 

[5352!)] 

■Fixed  plane          n 

[5352cl 

*  (2980)  The  angle  of  inclination  of  the 
ecliptic  to  the  fixed  plane,  given  in  [5353], 
being  put,  for  brevity,  equal  to  A  ,  we  shall 
h  ave  A  =  —  H  [5353, 5350,  535 1  a]  ;  and 
ês  =  — A.s'm.fv  [5348].  Suppose,  in  the 
annexed  figure,  that  C  R  represents  the 
equator,  C  B  the  fixed  plane,  C  L  the 
ecliptic,  .A/the  place  of  the  moon,  ML  a. 
circle  of  latitude,  perpendicular  to  the  ecliptic, 
MDB  the  arc  perpendicular  to  the  fixed 
plane  ;  then  the  difference  of  the  arcs  M  L, 
M  B,    will  be  veiy  nearly  represented  by 

BD=aug\eBCD  x  sm.CD  =  A  .sm.fv     [5352a,5345]. 
Hence  it  is  evident,  that  if  the  moon's  latitude,  above  the   fixed  plane,  be   expressed  by 
B M  =  s,     its  latitude,  counted  from  the  ecliptic,  will  be  very  nearly  represented  by 
ML  =  MB  —  BB^s  —  A.  sin.  fv=s-\-hs     [53526]  ;  as  in  [5352]. 

t  (2981)     The  expression  of    A    [5352a,  5353],  is. 


A  = 


_  (gp— èaç)   _D2 


g-l 


.  sin. X. cos.  X. 


Substituting  the  values  [5354,5355],  and  that  of    aç     [5356],  we  obtain, 

^  =  5132',9.ap  — S-'.SS  ; 
hence,  .^-j-8^S8 

"^^^    5132%9    • 


[5352(/] 
[5352e] 

[5357a] 

[53576] 
[5357«] 


692  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Inequality 

[5357]  OS  =  —  6,487  .  sin./  v  . 

depending 
on  the 

[5358]     It  would  be     —  13',436.sin./i; ,     if  the  oblateness  be  -\^,  which  corresponds 
°inb.        *^o  the  supposition  that  the  earth   is  homogeneous   [1592a].     Therefore,  if 
r5358'i     ^^^^  inequality  be  carefully  observed,  it  will  be  very  useful  in  ascertaining  the 
oblateness  of  the  earth. 

We  shall  noio  consider  the  variations  in  the  radius  vector,  and  in  the  moon^s 
longitude  arising  from  the  oblateness  of  the  earth.  We  may  deduce  them 
from  the  equations  [4753,  4754]  ;  but  it  is  more  simple  and  accurate,  to  use 
the  formulas  [919,923].  For  this  purpose,  we  shall  suppose,  that  the 
[5359]  differential  characteristic  6  refers  to  the  quantity  -^<i-?  —  a--.  We  shall  then 
observe,  that  the  functions     R,     rR,     [913,928'],  are  represented  by,  * 


[5360] 


R  =  —  Q^\     [4774a]  ;         rR'  =  r .  C^^_ 


dR\ 


Hence,  the  equation  [919]  becomes,! 


[5361]  0  =  -^+  -3-  +  2  .fUR+,.r .  ^- 


[5362] 


We  have,  in     R ,   the  term,î     R  =  2.(aj) — ia-p).-j  .  sin.x.cos.x.s.sin./y.    This 
contains  the  following  term. 


r5357rfl     ^f    '*'P  =^  3^*  '     ^^®   ^^^^  °^  ^^^^^  equations  gives     A  =  6',4S7  ,     as  in  [5357]  ;  and,  if 
ap  =  ji!r)     it  becomes     A=lS%4o6  ,     as  in  [5358]. 

*  (2982)     If  we  substitute  the  expression  of     Q     [5346i],  in     R     [5360],  we  shall 
obtain, 

[5360a]         =  1_^  (ap— |a?).D2M3  5sin,2X.(l— s2)^.sin,'-yy4-2s.sinX.cosX.sin>-fs2.cos^-i(l-«')^^; 
which  will  be  used  hereafter. 

t  (2983)     The  equation  [5361],  is  the  same  as   [919],  using  the    expression  of    rR' 
[5361a]      [5360],  and  that  of    iJ.  =  M+m=l     [914',5340']. 

X  (29S4)     The  term   of    R  ,     retained  in   [5362],  is  the  same]  as   that   in   [5360a], 
[5362a]     depending  upon     s.sinfv.     Substituting  in  it  the  chief  term  of    s;     namely,     s  =  7.sin.^« 


Vll.ii.>§.20]         EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  ô93 

éR  =  (a-. — iaç)  .  — .  7  .  sin.x.cos.x.cos.(gi' — fv — .').  [5303] 

This  term  of     sR     gives,  in    fs.dR,  an    expression  which  is  exactl}'  similar 

and  equal   to     iR .      For  the  differential   characteristic     d     [916'],   refers     [5363] 

only  to  the  moon's  co-ordinates  ;  and,  we  have,  by  noticing  only  the  preceding 

term, 


/  S.dR  =iR  . 
Then  we  obtain,* 

6.r.(  —  j  =  —  3  .  (etp — lap)  .  — .  7.  sin.x.cos.X.cos.(^T— j^ — 6). 
If  we  substitute  these  values  of   fôAR,     and     6.r.(-— j     [5364,5365], 


[5364] 


[5305] 


in  the  differential  equation    [5361],  we   shall  find,  that  the  expression     dr 
contains  a   term,  depending  on     cos.(gv — -fv — &)  ,     but  it   is  insensible,  not      [5366] 
having     g — 1      for  a  divisor,  which  the  corresponding  term  of    6s     has. 

[4897»"],  it  produces  the  term  given  in  [53G3],   which    depends  on    the  angle     (g-f)-v  ; 
—     being  used  instead  of    ti.     Now,  the  coefficient  of  this   angle,  is  of  the  order     ^ — 1 , 


or  ?n-  [5347c],  and  the  integration  of  dùv,  in  [5387],  introduces  g — 1  as  a  divisor; 
and  it  is  on  this  account,  that  the  terms  depending  on  the  angle  gv — fv  are  retained  by 
the  author. 


[53626] 
[53C9c] 


*    ("2985)      The    partial    differential    of    oR     [53G3],    taken    relatively    to     /• ,     and 

multiplied  by    — ,     gives  [536.5],  as  is  evident  from  the  nature  of  the  symbol     &     [5359].     [3366n] 

If  we  substitute  the  values  [5364,  5365]  in  [5361],  tliey  will  produce   in   it  an   expression,     ,._^.,, 

[.j36bol 

n  . 

which  we  shall  represent  by     ^.     Then,  if  we  put,  for  a  moment     rSi-  =  u,  the  equation 

*"  [5366c] 

[53611,  will  become     0  =-~ -{---]- -.      Multiplying  this    by     r^,      and    puUine;    for 

•-  «''■       •■         '"  [5366-/] 

(It,     its  chief  term     -^      [5081],      or     7~(Jv,     nearly,  it  becomes,     0  =  --^-\-u-\-U  ; 

^"'  .  ,  .  .  [•'536fie] 

which  is  of  the  same  form  as  [4S45],  supposing     jV=l.      Its   integral   [4847]  introduces 

the  divisor     i'  —  JV''^  ^=  P —  1  ,     which  is  nearly  equal  to    — 1;    because,  in  the  present 
case,    i  =  g — /    [4S46,  5363]  is  of  the  order     m'^     [53475f].     Hence  it  is  evident,  that    i^^cQfi 
u  =r6r  ,     is  not  increased  by  the  introduction  of  a  small  divisor  in  the  integration.     This 
agrees  with  [5366]. 

VOL.  III.  149 


69^  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

It  is  not  the   same  with  the  expression  of  the  longitude.     The   formula 
[923J  gives,  in     cUv,     the  following  terms  ;* 


,53(.-.  3df.fs.àR+2dt^6.r.('- 


[5368] 


r  .dv 

Substituting  the  value  of    ôR     [5363],   we  obtain,  in     dàv,     the  following 
term  ;t 

d.ôv  :=  —  • Vt — - — -  •— T  '7  '  sm.x.cos.x.cos.f^w — fv — ê). 

r^.dv  r^  \s      J        / 

But,  this  is  not  the  only  term  of  the  same  kind,  in  the  expression   of    div. 
[5369]     The  sun's   action  gives,    in     Q     [4806],  the  term      Q  ^'i:^^-J\  —  2s^). 

[5370]      Substituting  in   it  the  value  of    u     [4776],  we  obtain,   in     7?  «=  —  Q+- 
[5360],  the  expression,! 

which  gives,  in     àR,     the  term, 

[5372]  àR=:^m'u'\r^.Sf,s; 


*  (29S6)     Noticing  only  the  terms   depending  on   tlie   angle     gv — fv — d ,     or    those 
'•        "•'     which  produce  the  factor    s&s     in  [5373,  Sic],  we  may  neglect     or,     and  then  we  obtain 

from  [923], 

[53676]  ,,  Sdfi.  f  6AR+'îdfi.r5R' 

■■  •'  dSv  = 5-^ . 

r^.dv 

Now,  we  evidently  have     rSR'=.5.{rR') — R'&r  ;     and,  for  the  same  reason  as  in   [5367a], 

[5367c]     we  may  reject     R'5r  ;     then,  using  the  value  of    rR'   [53G0],  we  get     i-5R'=ô.r.(  —  j; 

hence,  the  preceding  expression  of    dSv     becomes  as  in  [5367]. 

t   (2937)     Substituting    fô.dR^SR  [5.364],  in  [5.367];  and   then   using  the  values 
[5363,5365],  we  obtain  the  expression  [5368],  by  a  slight  reduction. 

1  7-3 

r5370al         Î  (2988)     From     u     [4776],  we   deduce     —  ==  — ^  =  r^  .{l  —  s^},     nearly  ; 

multiplying  this   by     ^m'u'^.^l — 2s^),     we   get  the   value  of  the  term  of     Q     [5369]; 
and,  by  the  substitution  in     R     [5370],  we  obtain  the  term  [5371],  neglecting  quantities 
[53706]    qJ-  jj^p  order     s\     The  variation   of    [.5371],   relative  to  the  characteristic     6,     putting 
5r=0     [5367ff],  gives     iR     [5372]. 


vil. il.  §20.]         EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  595 

from  which  we  easily  deduce  the  following  expression  ;* 

3/é.di?+26.r.r^)   =  'i.m'u".r.sôs.  [537.3] 

We  have,  very  nearly,t    mii'\r^  =  »r,  also  g  =  1+f  m^  [5117or4828e]  ;      ^^^^^^ 
hence  the  function  [5373]  becomes, 

/(}R\  14. (p- — l).s5s 

3f6.dRi-26.r.(—J  =  r       "•  ^^^^^^ 

Substituting  in  it     as  =  —  ^''^~^""^\  — -sin.x.cos.x.  sin.>  [6351,5374a]; 

^~^         '■'  [5376] 

and   s  ^  7.sïn.(gv—ê)   [5050],  we  obtain,  in  [5375],  the  following  term;| 


(2989)     From  [5371],  we  get,  by  differentiation, 


r .  f'^)  =-im' u'\  r\  {i-2s^).  [5373al 


Jr  J 

Its  variation  relative  to  the  characteristic     5 ,     neglecting     <5r  [5367a],     gives, 

S.r.(^—^  =  ^m'u'^.r^.sès;  [53736] 

and,  from  [5364,  5372],  we  have    f  S.dR^  §m'.u'^r^.s5s.     Substituting   these  values  in 
the  first  member  of  [5373],  it  becomes  as  in  its  second  member. 

t    (2990)      We    have  nearly     r  =  a,    m'=-     [4937n,  &c.]  ;    substituting    these    in     [5374a] 

m'.u'^.i-^,     we  get     m'.u'^.r^  ^  ——  :=  m       [4S65]  ;    and,  from   [5094],  it  appears  that 

this  is  equal  to     m^     nearly,  as  in  [5374].     If  we  use  the  value  of  ^  ,     [5374],  it  becomes 

m'.  u  3.r3  =  4  .  (^—1  ) .     Substituting  this  in  [5373],  we  get  [5375].  '^^^''^^^ 

J  (2991)     Multiplying    together  the   values  of    s    and     5s,     [5376];    reducing,  and 
retaining  only  the  term  depending  on  the  angle     gv — fv — 6  ,     we  get, 

sis  =  —    21"— I)    '  ^  •  y  •  sin. X . cos.  X .  cos.  (gv  —fv  —  ê)  .  [5376a] 

Multiplying  this  by     — '- ,     we  obtain  the  expression  of  the  second   member  of  the     [537661 

dt- 
equation  [5375],  as  in  [5377].     Multiplying  this  last  function  by     — — -  ,     we  get  the  term 

of    d&v ,     corresponding  to  the  second  member  of  [5367]  ;  namely, 

V.dv  H    •'/•sin.X.cos.X.cos.(5-«-/t.-<!);  ^^g^^^^ 

adding  this  to  the  term  [5368],  we  get  [5378]. 


ê96  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

[5377]        3f6.dR-\r25.r.  f'l^^  =  —  7.(ap— la^).  —  .7  .  sin.x.cos.x.cos.fs-r— /r— :'). 

Multiplying  this  by     -^—  ,     we  obtain,  in  the  expression   of     cUv     [5367], 

a  term  which  is  to  be  added  to  that  in  [5368]  ;  and  the  sum  becomes, 

rco^oi                          -. ,                 \Odt^.(a.n-ia.a)   D^  .  ,  r         \ 

[5378]  dij'D  —  —  . A_l '  .—,./•  sm.x  .  cos.x  .  cos.r^-i' — fv — è). 

We   may  substitute  in  it,     a     for     r,     do     for      7idt     [603,  4828],     and 
^^^^^'^     n^rt^  =  1      [3709']  ;  by  which  means,  it  becomes,* 

[5379]  d&V  ==  — 10fl«.(ap — ia?)).-^.7.sin.X.C0S.X.C0S.(^?;— /i) — ('). 


(r 


This  value  of    d5v     corresponds  to  the  angle  contained  between  the  two 
[5380]     consecutive  radii  vectores  r   and    r-{-dr,    as  in  [923 — 925].     Now,  if  we  put 
this  angle  equal  to     dv^,     dv     will  reiiresent  its  projection  upon  the  plane  of 
the  ecliptic,  and  we  shall  have,  as  in  [925],t 


[5381]  dv  =  dv  .  -Tl -^= ^^  ; 

or,  very  nearly, 

[5382]  dv  =  dv^ .  ^  l+hs-—h-Jl,  J  • 


(2992)     Substitutina;  in  the  factor      v^r  •  T>     ^^"^i'^'^  occurs  in  [5378],  the   values 


[5379aj    ^jf^±^    r  =  a,     and     n^'a^  =  1    [5378'],  it  becomes, 


dv       -D2  _  m 

[53794]  ^a?'l^  —  ''''  "    a^   ' 

hence  [5378]  changes  into  [5379]. 

f  (2993)     The  expression  [5381]  is  nearly  the  same  as  tliat  in  [925],  changing    v    into 
V  ,     and     V      into     v     in  order  to  adapt  it  to  the  notation   in    [5380],  which  is   different 
from  that  in  r923'l,  observing  that,  on  account  of  the   smallness  of    s,     we   may   change 
[5381a]      ,  J  ds 

—     into     — .      Developing  [5381],  according  to  the   powers  and  products  of    i,     —  j 
dv,  dv  " 

neglecting  the  fourth  dimension  of  these  quantities,  it  becomes  as  in  [5382]. 


Vn.il  S-20.]         EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH. 


597 


Substituting  for     s     tlie  expression,* 


5  =  7.  sm.  {gv — c)  —  ^-^ — — ^  .  —  .  sni.  x  .  cos.  x  .  sin.fv  ;  [5383] 


we  get,t 


(h  =  dv, .  <  1+1 .  (c>-p — i«-?)  .  ~^.  y  .  sin.x.cos.x.cos.(^«— ^îj — 5)-f-&c.  >  . 

Hence  we  see,  that  to  obtain  the  value  of    J5« ,     relative   to   the  angle     v, 
formed  by  the  projection  of  the  radius  vector     r,     upon  the  ecliptic,  with  a 


[5384] 


*  (2994)  Substituting  in  [5050],  tlie  values  of  h  [5351],  we  get  [53S3]  ;  wiiich 
by  using  the  value  of  A  [5o57a],  becomes  as  in  [5383c],  omitting  for  brevity  the  symbol 
(3.  Its  differential  gives  [5383f/],  observing  that  /  is  nearly  equal  to  unity  [5347»/]. 
Squaring  these  expressions,  retaining  only  the  products  sin.^u.sin._/w,  cos.^u.cos._/i, 
which  produce  the  term  depending  on  cos.(^« — fv) ,  we  get  [53S3e,/],  whose  sum  is  as 
in  [53S30-]  ;  this  is  used  in  the  following  note  ; 


5  =  y.sin.^D — A.zm.fo  ; 
ds 


dv 


=  gy.cos.gv — ^.cos./«  ; 


is-  =  — ^7.3in.^y.sin./w-(-&z,c.  =  — ^Ay.cos.(gv — ■/i')-(-&ic. 


ds^ 


—  i-—  =  +gAy.cos.gv.cos.fv-{-iic.  =  igAY.cos.(gv—fv)-\-hc.  ; 
^■' -^-^^  i.(^-l).^y.cos.(^.-/.)  . 


[5383a] 

[53836] 

[5383c] 
[5383rf] 
[5383e] 

[5383/] 
[5383g] 


[53;'G«] 


[53866] 


t   (2995)     Substituting  [53S3o-],  in  [5382],  we  get, 

civ  =  dv,.ll-j-i{g—  I)  .Ay  .  cos.(gv  —fv}}  ; 

and  by  using  the  value  of    A     [5357a],  it  becomes  as  in  [5384].     Hence  it  appears  tliat 

this  reduction,  adds  to  the   value   of    dv  ,     the  term     dv^.^(^g — 1)  .,;3y.  cos.^^-u — J'v), 

or     dv.i(g — I)  .Ay.cos.{gv  — fv)     nearly;  which  by  the  substitution   of    A    [5357«], 

becomes  as  in  the  second   member   of  [5385].     This    term    of    dv  ,     is    a    part    of  that 

depending  on     ap — laçj,     which  is  denoted  by     d&v     in  [5359,  5379, 5385,  &c.].     Adding     [5386c] 

together  the  two   parts   of    dôv     [5379,5385],  we  get  the  complete  value  [538G],  and  its 

integral,  putting    /=  1,     gives    i5y   [5387].     This  expression  is  obtained,  to  a  somewhat    [5386(i] 

greater  degree  of  accuracy,  in  [12995]  ;  where   small  terms    are   computed,  of  the   order 

3m  .  ■  .  [5386e] 

—  ,     in  comparison  with  those  which  are  here  investigated. 


VOL.   til. 


150 


598  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

fixed  light  line  ;  we  must  add  to  tlie  preceding  expression  of    div     [5379], 
the  term, 

[5385]  (/.îî;  =  ic;î;.(ap— lap),— .7.sin>.cos.x.cos.(g-«;— /ij— 0)     [53866]  ; 

which  gives, 
[5386]  (/5t7  =  — V'rft).(ap— la.?),— .7.sin>.COS.X.cos.(o-i;— /«— 0)      [5386f/]  ; 

and,  by  integration, 

(ap — ^as)    D^        .  .      .  r       .\ 

[5387]  ÔV  =  —  ^.  —  — ^-^.-^.7.sm.x.cos.x.sm.(^i)— /i) — "). 

'nequality  g 1  W 

This  is  the  only  sensible  ineqicality  in  the  moon^s  motion  in  longitude,  arising 
from  the  oblateness  of  the  earth.  It  may  be  observed,  that  fv — gv^é* 
expresses  the  longitude  of  the  ascending  node  of  the  orbit,  counted  from  the 
moveable  vernal  equinox  ;  hence  it  follows,  that  the  expression  of  the  true 
longitude,  in  terms  of  the  mean  longitude,  contains  the  following  inequality  ; 

[5389]  (5v=]|.-^^^^^—,—-,7,sin.x.cos.x.sin. (longitude  of  the  ascending  node). 


in  Ion 

gituJs 

depending 

on  tlie 

oblateness 

of  the 

earth. 

[5388] 


[5390] 


The   coefficient  of  this    inequality  isf     5^552,     if     p  =  ^i^  ;     it  becomes 
11 ',499,     if    P  =  ^iô- 


*  (2996)     It  is  evident,  from  [4813,4817],  that     gv—ê     represents  nearly  the  moon's 
[5388rt]    distance  from  the  ascending  node  on  the  fixed  ecliptic,  counted  according  to  the  order  of  the 

signs  ;  and    fv     [5-34.5],  the  moon's  distance  from  the  moveable  equinox,  counted  in  the 

same  order.       Subtracting    the   first    of    these    expressions   from  the  second,  we    obtain 
[53886]    fv — gv-^é,     which  must   evidently  represent  the  distance  of  the  node  from  the  equinox, 

or  its  longitude.     Hence, 
[5388c]  —s\n.{gv—fv—ê)  =  s\n.(fr—gv+ê)  =: sin. (longitude  of  the  ascending  node). 

Substituting  this  in   [5387],  we  get  [5389]. 

t  (2997)     Substituting     A     [5357o],  in  [5389],  it  becomes, 
[5390a]  Sv=^'^.Ay.  sin. (longitude  of  the  ascending  node). 

The   values  of    A,     corresponding  to    the  ellipticities     ^ij,     2-^,     have  already  been 

computed  in  [5.357,5358],  and  found  to  be    6%487,     13%436,  respectively.     Multiplying 

[53906]     ^j^ggg  ^,y     ^.y=  0,855767     [51 17  line  5],   we  get  the  values   [5390].     If  we   put  the 

coefficient  of  [5389]  equal  to     A',     we  shall  have,  by  comparing  it  with  [5357a], 
[5390c]  A'='i.AY,       or,       A=—.A'; 


VII.ii.§20.]         EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  599 

The  ohlateness  of  the  earth  affects  also  the  motions  of  the  perigee  and  nodes 

[5390'! 

of  the  lunar  orbit.     For,  the  value  of     Q     is,     by  this  means,  increased  by 
the  quantity,* 

Q=(ap-ioLç).(l-fs^).{i-(l-s'*).sin.^.sin.>-2s.sinx.cosx.sin/tJ-s^cos2x|.Z)V.      [5391] 
This  produces,  in  the  equation  [4754],  the  following  term  ;t 

and,  by  substituting  for     u,     its  approximate  value, 

u  =  -  .{l  +  e  .cos.(cv — -n)]      [4826],  [5393] 

and  observing,  that     h^     is  very  nearly  equal  to     a     [4859],  we  obtain,  in 
the  differential  equation  [4961,  or  5392a],  the  terms. 


the  equa- 
tion 


2.(ap_W)   ^^  (l_3.sin.^X).  e.  C0S.(C.-.).  ^53^95] 


a  a^ 


substituting  this  in  [5357e,  c],  and  reducing,  we  get  the  following  equations,  which  may  be 

used  hereafter  ; 

A'  =  4392%C.ap— 7^6  ;  [5390rf] 

A'+V,6 


ap  = 


4392%6  [5390e] 


*  (2998)     If  we  change  the  signs  of  the  two  factors  of     Q     [53466],  which  does  not 
alter  its  value  ;  and  then  vary  the  place  of  its  last  term,  we  get, 

Q=(a.p — .Jtt;p).Z)"-.M^.{|(l — s^)~ — (1 — «^)-.sin.^X.sin.yt)-2«.sinX.cosX.sin./r-i^.cos2x|.      [5391o] 

Dividing  the  last  factor  by  (1 — s^)^,  and  then  multiplying  by  the  equivalent  expression 
1 — ^s-,  neglecting  terms  of  the  order  s^,  we  get  [5391].  If  we  neglect  also  the  terms 
depending  on     s,     and  substitute     sin.-yu  =  i — i.cos.2fv,     it  becomes, 

^  =  (ap— ia?).D2.M3.  {1— i.sin.2x+|.sin.2x.cos.2/j;|  ;  [53916] 

which  is  used  in  the  next  note. 

t  (2999)     Upon  the  same  principles,  by  which  we  have  obtained  the    equation  [4755] 
under  the  form  [5347/],  we  may  reduce  [4754],  to  the  following  form, 


600  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Hence  we  easily  find,  that  the  motion  of  the   perigee  is  increased  by  the 
following  quantity  nearly  ;* 


1^396]  5n  =  (ap_la?).^.  v.  {1  — |  .  sin.==X| . 


Increment 
of  the 
motions 
of  tlie 
perigeR 
and  nude. 


It  is  evident,  from  the  equation   [4755J,  that  the  retrograde  motion   of  the 
node,  ivill  he  increased  by  the  same  quantity.     If  we  reduce  it  to  numbers, 
[5397]     we  obtain,t     0,00000026384.z)  ;     which  is  insensible. 


[5392a]  0  =  ^  +  K--^.f^^ 

rfll2    "  h'i        \dh 


[5392i] 


This  contains  the  most  important  part  of  the  terms  now  under  consideration  depending  on 
Q  ;  the  neglected  quantities  being  of  a  different  form  and  order  from  those  which  are 
retained  in  [5394,5395].  Now,  the  expression  of  Q  [53916],  gives  in  [5392a],  tlie 
terms, 

■      _  ^  .  (^1?^  =   _  i^lZ^^  .  DhL\  \  l-|.sin.2x+i.sin.5X.cos.2> } . 

If  we  neglect  the  part  depending  on  the  angle  2/î)  ,  it  becomes  as  in  [5392].  If  we 
use  the  values  [4937n],  and  put,  for  brevity, 

[5392c]  B  =  (a?— iciffi)  .  ~  .  (1— f.sin.^X) , 

we  get, 

_  1      ('B\    _  _  R       2 
[5392d]  Ifi'  \du)   ~ 

Substituting     rt^  =   —  .  (l-)-2e.cos.Ci;)      [5393],  and  neglecting     c^  ,     it  becomes, 
[5392e]  2  JS  .  -  .  cos.ci;  ,     as  in  [5394, 5395]  : 

hence  the  equation  [5392rt],  is  reduced  to  the  following  form, 
[5392/]  0  =  ^  +  M  —  -  —  2  B .  -  .  COS.CÎ). 

*  (3000)     Neglecting  terms  of   the  order     e^  ,  e'^,     we  find   that  the   coefficient    of 

[5396a]    -  .  cos.cy  ,     in  the  equation  [4961],  is  represented   by     — -p     [4975];  and,  it    is    evident, 

[53966]    that  the  terms  depending  on     B,     in  [5392/,  or  49G1],  augment  the  value   of    p     by  tlie 

quantity     &p  =  2B  .     Now    the  motion  of  the   perigee    is    represented,    in   [49846],  by 

[539bc]     ^Y — y/yz:^).j;,     which  is  very  nearly  equal  to     ipv  ;     so,  that   if    p     be   augmented  by 

[5396rf]    f5p  ,     the  motion  of  the  perigee  will  be  increased  by     ^5p.v  ■=^  Bv  ,     as  in   [5396,5392f]. 

t  (3001)     If  we  neglect  terms  of  the  order     e'°,  e^,  &c.,     and  also,  for   brevity,   the 


VII.  ii.  §  20.]        EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.  601 

We  shall  now  make  an  interesting  remark,  upon  the  preceding  inequality  of 

.....  .        L  "^^y  D 1 

the  moon's  motion  in  latitude.    This  inequality  is  nothing  more  than  the  reaction    "^^'J'^^y^ 

of  the  nidation  of  the  earth^s  axis,  discovered  by  Bradley.     To  prove  this,  we    'reaction 

shall  put  7  for  the  inclination  of  the  lunar  orbit  to  the  plane  we   have  spoken     [5398] 

,  ....  nutation 

of  in    [5352],  which  passes  always  through  the  equinoxes,  and  is   inclined    °[^'-^^_ 
to  the  ecliptic  by  an  angle  [5353],  equal  to      — — - — -  .  -^  .  sin.  x  .  cos.>^.      [5399] 
The  inclination  of  the  lunar  orbit  to  the  ecliptic,  will  be, 

symbol     ê,     we  shall  find,  that  the  retrograde  motion  of  the  nodes  is, 

1  \/iW—  1  i  •  "  =  hp"-  »  ,     nearly  [5059]  ;  [5397a] 

observing,  that    p"y-sin.^u     [5053],  is  the  term  of  [5049, or 4755],  depending  on     sin.^y. 
The  inspection  of  the  value  of     Q     [5391a],  shows,  that   the    quantity     (y^)     produces     [5.39741 

nothing  of  importance   in    [4755].     If  we   neglect     s^ ,     and  put     h^=a,    u=a~^,     in 
the  other  terms  of  [4755  line  2],  we  find,  that  this  equation  becomes, 

Multiplying  the   equation   [5392f/],  by     h-s ,     and    substituting  the  preceding  values    of 
h^,    u,     we  get     — s.(—j=^  —  Bs.     Again,  if  we  take  the  partial  differential  of     Q,     [5397(i] 
[5391a],  relative  to    s,     and    multiply  it  by     — a,     putting     M  =  a~",     we    shall    "et     [5397e] 
[5397^].     Neglecting     s^,     putting     sin.^i)  =  i  —  J.cos.2/y ,     and  omitting   the   terms 
depending  on    fv,     2/y,      we   get   [5397 A].      Substituting      cos.^X^  I  —  sin.^X,      and    [5397/] 
reducing  successively,  using   B  [5392c],  it  becomes  as  in  [5397 ij  ; 

=  (ap— U?)  .— .5.^I-J.sin.2x+2.cos.2x^=  (ap— ^aç;) .-.«.? 3— f.sin.sx'       [5397ft] 

=  3Bs.  [5397t] 

Substituting  the  values  [5397</,  i],  in  [5397c],  we  get, 

rf(/«  lids  „ 

0=-T^+«+2S«,  or         0=-~^s-{-2B.v.sm.gv,     nearly  [5383]  ;  [5397ft] 


hence  the  value  of  p"  [5053],  is  increased  by  the  quantity  2B ,  nearly  ;  consequently 
the  motion  of  the  node  ip"v  [5397a]  is  augmented  by  the  quantity  Bv  ,  being  the 
same  as  that  of  the  perigee,  [5396d],  as  in  [5397]. 

Substituting,  in  [5396],  the  values  [5354 — 5356],  we  get, 
VOL.  III.  151 


[.5397i] 


602 


[5400]      *        (q-p-U^)  D^ 
.s:— I 


[5401] 


THEORY  OF  THE  MOON;  [Méc.  Cél. 

—  .  sin.X  .  COS.X  .  COS.ÇgV — -fv — li)  =  inclination  of  orbit  to  the  ecliptic. 


Now,  the  area  described  by  the  moon  about  the  earth's  centre  of  gravity,  is 
\r^'.dv     [372«].     This  area,  projected  upon  the  ecliptic,  is  decreased  in  the 
[5401]     ratio  of  the  cosine  of  the  inclination  of  the  moon's  orbit  [5400]  to  the  radius  ; 
therefore,  it  is  represented  by, 

[5402]        ^r-.dy.cos.  <  } — '.  -^.sm.X.COS.X.COS.(g?;— /i; — è)  \  =  projec.  of  the  area  èrS.rfti. 

Hence,  the  expression  of  this  area  contains  the  inequality,! 


[5397m]  ^^  ^  ^^  ^  0,00000026384.1',     as  in  [5397]  ; 

[5397n]  and,  by  putting  ti  =  SOC,  it  becomes  (5ra  =  0',3,  corresponding  to  one  revolution  of 
the  moon.  This  part  of  the  motion  of  the  perigee  is  insensible,  in  comparison  with  its 
whole  motion     0,00845199. «     [5117  line  2]  ;  being  only     ^t^utt     part  of  it. 


[5397o] 
[5400a] 


*   (3002)     In    the   annexed  figure,  let 

AR  be  the  equator,  AJVB  the  fixed  plane, 

AEl)  the  ecliptic,  JVEM  the  moon's  orbit  ; 

then,  if  we  make  arc  A'iVi=arciVB^90'', 
[5400&]    and    describe    about    N,    as    a   pole,    the 

2iïc  MDB,     we   shall   have    mcJ\IB=^y 

[5398'],     angle    BAB=A      [5357«].  

Moreover,  we   have,  very,  nearly,  in   the  -^^  Enuator  _k 

[5400c]     triangle     BAB,     ^vcBB  =  A.ûn.AB=  A  .sm.{A]<l-\-QQ'^)  =  A.cos.AN  ;     and,    as 

^iV  is  nearly  equal  to     AE=z  fv—gv-\-d  [5388],  we  have     BB  =A.cos.{fv—gv-\-è); 

hence, 
[5400rf]  MD=^MB—BB  =  y—A.cos.{fv—gv-\-è)  =  y—A.cos.{gv—fv—è). 

Now,  from  the  extreme  smallness  of  the  arcs  DB,  EK,  it  is  evident,  that  the  arc 
MB  represents  very  neariy  the  value  of  the  angle  MEB,    or  the  inclination  of  the  moon's 

[5400e]     orbit  to  the  ecliptic.      This  agrees  with  [5400].      We  may  moreover  remark,  that  the  angle 

p-u /■« — â,    or     fo — gv-\-^,    corresponding  to  the  distance  of  the  node  from  the  equinox 

varies  only   about     3'',     in  a  periodical  revolution  of  the  moon  ;  consequently,  the  angle  of 

[5400/]  inclination  [5400]  alters  but  little,  during  that  revolution;  and  the  factor  of  ^r'^.dv,  in  the 
inequality  [5403],  is  neariy  constant  in  the  whole  of  that  period. 

t    (3003)       Putting,    for    brevity,     A'=  A.cos.{gv — fv—è)     [5357«],    in   the 
"•        "■'    expression  of  the  projection  of  the  area  [5402],  and    then  developing,  as  in  [61]  Int., 


VII.ii.§90.]    EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.        603 

[5403] 
[5404] 


,    o     I     (o-p— Jaa)    D^        .  /  /•        .\ 

ir.  dv.  — - .  — 5-.7.Sin.X.COS.>,.COS.(g"l' — -JV — (')  =  a  term  of  the  projection  of  ^r^.dv  ; 

Ô 

and,  as  Ave  have,  very  nearly,*     i".dv  =  ar.dt,     dt  denoting  the  moon' s  mean 
motion,  this  inequality  will  be  represented  by, 


IjD".  dt  X-^' — ^.7.sin.X.COS.X.COS.(^T — -fv — (')  =  a  term  of  the  projection  of   ir2.rfu.  [5405] 


Multiplying  this  expression  by  the  moon's  mass,  which  we  shall  represent 
by  L  ;  then,  dividing  the  product  by  \dt,  Ave  obtain  the  momentum  of 
the  moon's  force  about  the  centre  of  gravity  of  the  earth,  arising  from  the 
oblateness  of  the  earth.f  Hence  we  get,  for  this  momentum,  the  following 
expression  ; 


[5406] 
[5406'] 


L.D^.— — '~ — ^•^.sin.x.cos.x.cos.f^'i; — fv — 0  =  momentum  of  the  moon,    (i)      [5407i 

<r 1  \0  J  /  \  y       Momen- 


S 

In  consequence  of  the  equality  hetiveen  the  action  and  reaction,  the  same  cause    ■■;/ «""he 


turn  ofthe 
moon  cor- 
respond- 
ing toth 
oblatenesa 
ofthe 
earth. 


neglecting  the  second  and  higher  powers  and  products  of    A',     it  becomes, 

^r^.dv.coa.{y — A')  =  ^'fi.dv.\cos.y-\-A'.s\u.y\  =  ^r'^.dv.cos.y-\-^r^.dv.Ay,     nearly.  [54035] 

Re-substituting  the  value  of    A!,     in  the  last  part  of  this  expression,  we  obtain  the  term 
[5403]. 

*    (3004)     We    have      r^.  dv  =  a^.ndt  .\/l  —  e^      [1057];    and,  bj'    neglecting     e^ 
changing  also  the  mean  motion  ndt  into  dt,  so  as  to  correspond  to  the  notation  in  [5404],     1^^040] 
it  becomes     r-.dv  =  a^.dt,    as  in  [5404]  ;  substituting  this  in  [5403],  we  get  [5405].     In 
this  process,  we  neglect  the  consideration  of  the  perturbations  of  the  moon's  motion  by  the     [54046] 
sun's  action,  using  the  elliptical  value  of    r^.dv     [5404a];    observing,  that  the    rejected 
terms  are  of  a  different  form  or  order,  from  that  in  [5405]. 


[5406a] 


f    (3005)      The  arc    which  the  moon  describes  in  her  orbit,   in   the  time  dt,  being 
resolved  in  a  direction  perpendicular  to  the  radius     r,     is  evidently  represented  by  i\dv  ; 

consequently,  the  velocity,  in  that  direction,  is     ^--j-',     and  the  force  is  proportional  to  it. 

Multiplying  this  by  the  radius  r,  and  by  the  mass  L,    we  get  the  corresponding  momentum 

of  the  moon  [29'],  [54066] 

r^.—  .L,         or  .L,     as  m  [5406']. 

dt  2  dt 

Substituting,  in  this  last  expression,  for     ^r^.dv,     the  term  given  in  [5405],  we  obtain  the 

corresponding  part  of  the  moon's  momentum,  as  in  [5407]. 


[5406c] 


604  THEORY  OF  THE  MOON  ;  [Méc.  Cél 

must  produce,  in  the  particles  of  the  earth,  a  momentum  which  is  equal  and 
contrary  to  the  preceding.  This  momentum  is  indicated  by  the  nutation  of 
the  earth's  axis,  and  we  may  determine  its  value  by  means  of  the  formulas 
[5408]  ij^  book  V.  ^  6.  For,  we  see,  in  [3101],  that  if  we  put  F  for  the  obliquity 
of  the  ecliptic  to  the  equator,  the  moon's  action  upon  the  earth  produces,  in 
consequence  of  the  oblate  form  of  the  earth,  an  increment  in  the  angle  V, 
which  is  represented  by,* 

[5409] r-. r  .7  .COS.  (gv—fv — â)  =  increment  of  the  obliquity   V  ; 

I  and  >^  being  the  same  as  in  that  article.  The  element  of  the  rotatory 
[a409]  jj^o|.Jq„  of  the  earth  being  supposed  ndt  [3015]  ;  the  sum  of  the  momenta 
of  the  forces  acting  upon  each  particle  of  the  earth,  multiplied  by  the  mass 
of  the  particle,  is  equal  to  nC  ;  C  being  the  momentum  of  inertia 
of  the  earth,  relative  to  its  axis  oi  rotation.!      io  reduce  this  momentum  to 


[54096] 


*  (3006)     Of  the    five    terms   which  compose   the    vaUie    of    ê     [.3101],  and  of    ê' 
[3360  or  3378],  or  that  of     V,     in  the  notation  [5408],  the  first  is  constant  ;    the  second 
"      is  secular  ;     the /bwrtA  and  _^/i:/i  are  small,  and  depend  on  the  places  of  the  sun  and  moon. 
The  third  is  that  upon  which  the  nutation  depends  ;  namely, 


^\''.cos.if't  +  pJ) 


(1+x)./ 

c'   [3086]  being  nearly  the  same   as     7     [5398']  ;  and, 
[5409c]  —f't—p'  =fv  —gv  +  é     [3086',  5388], 

representing  the  longitude  of  the  moon's  ascending  node,  counted  from  the  moveable  vernal 
equinox.     Substituting  these  values  in  [54096],  it  becomes, 

[5409(i]  7T-,-T->,-cos.(^«— /r  — a). 

Now,  the  mean  increment  of  v,  in  the  time  t,  being  represented  by  t  [5404],  it 
[5409e]      will  follow,  from  the  equation  [5409c],  that     —f=f—g  =  'i—g,     nearly  [53475r],    or 

f'  =  g — 1  ;  substituting  this  in  [5409f/],  we  get  the  increment  of  the  inclination  V 
[5409/]     [5409].     We  may  remark,  that  this  use  of  the  symbol     V    is  restricted  to  §  20  [5408]  to 

[5422]  ;  in  other  parts  of  this  chapter,    V    denotes  the  function  [53-36,  he.]. 

t  (3007)  The  angular  velocity  of  a  particle  of  the  earth  about  its  axis  of  revolution 
being  n  [5409'],  its  actual  velocity,  at  any  distance  r,  from  the  axis,  is  nr^. 
Multiplying  this  by  the  same  radius     r, ,     and  by  the  mass  of  the  particle     dm,     we   get 


Vll.ii.  .^20.]    EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.         605 


[5411] 


the  ecliptic,  we  must  multiply  it  by  the  cosine  of  its  obliquity,  or  by,* 

we  shall,  therefore,  have  the  following  inequality,  in  the  momentum   of  the 
earth  [541 U]  ; 

l-K.nC.s'm.V 

7  .  COS.  fgV JV ÔJ  =^  inequality  in  the  earth's  momentum.  [5412] 


We  have,  in  [3098], 


[5413] 


m  t    denoting  the   mean    motion   of  the  earth  [3059]  ;    alsof     Knf  =  -^  ;      [5414] 

a     being  the  moon's  mean  distance  from  the  earth  ;  and,  since  we   represent 
the  moon's  mean  motion  by     t     [5404],  and  the  mass  of  the  earth  by     M 

[4757]  ;    we    have,  very   nearly,  J     —  =  1  ,     which  gives        \.m^  =  —  ;      [5416] 

(I  JYJ. 


[5415] 


[54105] 


the  momentum  of  this  particle,  equal  to  n.r^.dm  [29].  Integrating  this,  relative  to  the 
whole  mass  of  the  earth,  it  becomes  n  .fr/'.Jm;  in  which  r/^  is  represented  by 
z"^-\-y"^,  of  the  formula  [229],  the  axis  of  rotation  being  z";  consequently,  this  expression 
becomes, 

n.fr/^.(!m  =  n.f{x"^-^y"^)  .(lm=^n.C     [229],    as  in  [5410].  [5410c] 


[5411a] 


*  (300S)     Putting  the  function  [.5409]  equal  to     5V,     the  whole  obliquity  will  become 
V-\-ûV.  Its  cosine,  by  [61]  Int.  is  represented  by  cos.V — iiV.sm.V ,  nearly.  Multiplying 
this,  by  the  momentum     nC  ,     it  produces  the  term,   —nC.sin.F.tS?^;  and,  by  substituting     [54ni] 
the  value  of    oV     [5409],  it  becomes  as  in  [5412]. 

t  (3009)     This  is  easily  deduced  from       X  .  w^  =  —      [.3079],    changing      L'      into 

L,     and     a'     into     a,     to  conform   to  the  alterations  in  the  notation,  which    is  used  in     [5414a] 
[3073,5406,5414].     We  may   also  observe,  that   in   deducing  the   value    of    /     [5413], 
from  [3098],  we  must  change     h     into     V,     to  conform  to  [3357,  5408]. 

J  (3010)     The  mean  increment  of     v  ,     in  the  time     t ,     is  very  nearly  represented 

by     nt     [5095]  ;  consequently  that  of    dv     is     mit  ;     and  as   this   is   put   equal  to     dt, 

[5415fl ] 
in  [5404],  we  shall  have     n=  1  .     Substituting  this  and     [i^M+m     [4775"],  in  [3700], 

VOL.  III.  152 


606  THEORY  OF  THE  MOON  ;  [Méc.Cél. 

thus,  the  preceding  inequality  becomes,* 

[5417-1 .  \Z L  .y.s'm.V.COS.V.COS. (gV—fv â)  =  inequalitymthe  earth's  momentum. 

4M  g — 1 

We  have,  from  [2960— 2962], t 
[5418]  2  C—A—B^^.  ^ .  (a  p— i aç)  .  D\f  3  u  .  R\  d R  ; 

[5419]      p     being  the  oblateness  of  the  earth;     D    its  semi-diameter;     R     the  radius 


[5420] 
[5421] 


of  one  of  its  particles,  whose  density  is    n  ;    and    *    the  semi-circumference, 
whose  radius  is  unity.     The  mass  of  the   earth  is  Î     M  —  i-^.f  3n.R-.dR  ; 


[5415t]     we  get      — ^ — =  I  ;     which,  by  neglecting  the   mass   of  the   moon     m,     in  comparison 

M 

[5415c]     with  that  of  the  earth     M  ,     becomes     —  =1,     as  in  [5416].      This  gives     a^  =^  M  , 

and,  by  substituting  it  in  [5414],  we  obtain  the  expression  of    X.m^    [5416]. 

*  (3011)     From  [5416]  we  get      "*^  =  TJ*  5     hence  [5413]  becomes, 

3i      (2C-A-B)     (1+X) 

substituting  this  in  [5412],  we  get  [5417]. 

t   (3012)      Subtracting   the   sum  of  the    values   of    A  ,  B     [2960,2961],   from     2C 
[2962] ,  we  get, 

[5418a]  2C-A—B^^^  .  o.^.{h-l^).  f^^  p  .d.a^  =  -.*  .{^h—l^^).f^'?.3a''.da  ; 

in  which  ip  [2951],  is  the  same  as  in  [5333'],  and  A  =  p  [5335'*].  Moreover,  we 
[5418i]     must  change     «,    p     [2947],  into      R,    n     [5419,5420],  to    conform    to    the    present 

notation  ;  hence  the  last  expression  [5418a]  becomes, 
[5418,]  ÇIC-A—B  =  '^ .  *  .  (ap-èap) .  /„i  m  .  R^ .  clR. 

The  two  members  of  this  equation  are  not  homogeneous  ;  for  in  the  first   member,     ji,  B, 

C  [2920 -2922],  are  of  the  j^/cA  order  in  R,  and  the  second  member  is  only  of  the 
[5418rf]     ffiiy(]  order  ;  we   must,  therefore,  multiply  the  second  member,  by  the  square   of  the  mean 

radius  of  the  earth  D  [5334],  which  is  taken  for  unity  in  [2947']  ;  and  then  it  becomes 
[.5418e]     as  in  [5418].     In  the  original  work,  the  factor     3,     under  the  sign    /,     is   accidentally 

omitted. 

X  (3013)     This   is   similar  to    the    expression   [1506a],  changing  the  notation,  as  in 


Vll.ii.<^2l.]  EFFECT  OF  THE  SPHEROIDAL  FIGURE  OF  THE  MOON.  607 

which  is  to  be  substituted  in  [5418]  ;  and  then  the  resulting  value  in  [5417], 
changing  also  the  obliquity   of  the   ecliptic     V    [5408],  into     x     [5841];      [5422] 
hence  the  inequality  [5417]  becomes, 

L.  /)-.  ^^ -.  7. sin. X. COS. X. cos. (^« — -fo C)  =  inequality  in  the  earth's  iiioiucntuni.  [5423] 


[5424] 
The  ine- 


This  expression  is  the  same  as  that  in  [5407],  ivith  a  contrary  sign.  Hence 
it  follows,  that  the  preceding  ineqiiality  of  the  moon's  motion  in  latitude,  is  the 
reaction   of  the  nutation  of  the  earth's  axis;    and,  that  there  would  be  an    quality 

'  -^  '  in  the 

equilibrium  about  the  centre  of  gravity  of  the  earth,  by  means  of  the  forces  which    T^°^L\> 
Ijroduce  these  two  inequalities,  supposing  all  the  particles  of  the  earth  and  moon  to    action 
be  firmly  connected  loith  each  other  ;  since    the   moon  compensates   for   the    Titil"" 

eartli's 

smallness  of  the  forces  which  act  on  it,  by  the  length  of  the   lever  to  which    ''''''■ 
it  is  attached. 

21.     To   notice  the   effect  of  the  moon's  figure,  which   is    not    exactly 
spherical,  we  shall  observe,  that  it  introduces  into     Q     [4756],  the  term, 

5V'                                                      SV 
(M  +  ni)  . [4773],  or  more  simply,     ;  f^^^^l 

because,  we  have  put  M+m  =  1  [4775"].  Now,  from  [1505, 1809',  4770'], 
we  obtain,* 


[5426] 


[54l8i].     Substituting  the  value  of    AI    in  [5418],  we  get, 

2  C—A—B  ==  i  .  (ap— >ç) .  D2  M  .  [5421a] 

and,  by  using  this  expression,  and  tliat  of     V  =  X     [5422]  ;  we  may  reduce  the  inequality 
[5417],  to  the  form  [5423]. 

*  (3014)  We  may  neglect  the  terms  of  V  [1505],  which  are  divided  by  r* ,  on 
accountof  their  smallness  ;  also  those  depending  on  y<°\  F''',  as  is  done  in  [1809',  1811], 
and  then  it  becomes,  by  accenting  the  letter     V,     so  as  to  conform  to  the  notation  [4769], 

F'  =  |./„V.d.«3+'^./„'p.rf.(«=r^=')=   7+'^:-/a'P-'^.(«^î^'^0   [5429].    [5425»] 

Substituting  this  in  [4770'],  we  get     àV     [5426]  ;  the  limits  of  the  integral  being  changed 

from     0,    1,      to      0,    a.     Multiplying  the  expression  of    5V'     [5426],    by     M-f-m^l     [54256] 

[4775"]  ;  and  then  dividing  by     m     [5429],  we  get  [5430]. 


608  THEORY  OF  THE  MOON  ;  [Méc.  CéJ. 

[5427]     the  integral  being  taken  from     a  =  0  ,     to     a ,     equal  to  the  moon'' s  semi- 
[5428]     diameter,  which  ive  shall  denote  by     a ,     and    ?     being  the  density  of  the 
[5429]     stratum  of  the  moon  corresponding  to     a.     We  have     m  = -| -^  ./;' p.  d.a^ 
[1506«]  ;  hence  we  deduce, 

^  '        m  5?-'.  /j,''  I' .  ri  .  a'* 

To  determine    f"  p.d.(a^.Y'--^)  ,     we  shall  observe  that  we  have,   in   [1761], 
for     Y  <-' ,     an  expression  of  the  following  form,* 

Y(2)  =  h'.  (X  — (x2)_j_/t".,a,^lZ:;i;i.sin.a+/t"'.  f^.V/ï^^-cos.« 
_1_  II"",  (1  _,a,a)  .  sin.  2^+/i'.  (1— ftj.)  .  cos.2^  . 

Then,  the  properties  of  the  axes  of  rotation  [1753 — 1757],  give,t 

5432]  0=/;p.fL(«^/O;         0=f;?.d.{a'h"');         O  ^f^  e.d.(a' h^)  : 

and  then,  from  [2948—2950],  we  obtain,! 


[5431] 


*   (3015)     The  expression  of     F->     [5431],  is  the  same  as  in  [17G1],  increasing  the 
accents  on     h  ,     by  unity. 

1(3016)     Substituting  the  expression  of     F'^'     [5431],  in  [1757],  we  get, 

^^^^^"^  4-a.(l-,j.2).sin.2a./;  f.d.{a^h"")+^u{l- f-^~).cos.2^.f,'p.d.{aVi^). 

Comparing  this,  with  the  value  of     U'"^     [1753],  we  get, 

H=-  a.  r,"  p.rf.(«^A')  ;      H'  =  a./„«  p.d.{a^h")  ;      H"  =  a,  /„«  p.d.{a%"')  ; 
r5432H 

Jf"'=cL./„»p..Z.(«W");       if""=o../oV.f/.(«=AO- 

Now,  the  properties  of  the  principal  axes  give,  in  [1754],    12'=  0,     H"  =  0  ,     Ji"'  =  0; 
[•''432c]     gjji^gtit^ting  these  in  [54326],  and   dividing  by     a  ,     we  get,  from   the   second,  third   and 
fourth  equations,  the  values  [5432]. 

t  (3017)  Substituting  the  values  of  A,  B,  C  [2948— 2950],  in  2C—A—B, 
we  get  the  expression  [54336],  by  putting  cos.^ra  +  sin.^  î?=  1.  This  is  easily 
reduced  to  the  form  [543.3c],  by  introducing  the  value  of  F^'  [5431],  and  neglecting  the 
[5433a]  terms  depending  on  h",  h'",  h"",  on  account  of  the  integrals  [54.32].  We  may  also 
neglect  the  term  depending  on  cos.2zï;  because,  at  the  limits  of  the  integral  -3=0 
zi  =  2*,  it  has  the  same  value  ;  and  the  integral  taken  between  these  limits  vanishes. 
Hence  we  have, 


Vll.ii.§21.]    EFFECT  OF  THE  SPHEROIDAL  FIGURE  OF  THE  MOON. 


609 


B-A  =  II 


Thus,  Ave  have,* 


[5433] 
[5433'] 


=  3<x..f.p.d.{a^h').{^  -f;.2)34a.(Zw+3a./.p.(/.(a5/i^).(^— p.2).(l— a2).cos.2«4"'.ffe 
=:3a./.p.f/.(a5  h'  ).(^—,jP)^.diJ..d7z. 

Now  we  have,  by  the  usual  rules  of  integration, 

f~"'du  =  2^;         f_^{i—i^?y.dix  =  ^\     [2933i,/,or3569e]; 

substituting  these  in  [5433(Z],  we  get  [5433].  In  like  manner,  if  we  substitute  the  values 
of  A,  B  [2948, 2949],  in  B — A,  we  get  the  first  expression  [5433^].  Substituting 
in  this,  the  value  of  Y"*-'  [5431],  and  neglecting,  as  above,  h",  h'",  h"",  we  get 
[5433A]  ;  reducing  also,  by  means  of  cos.^sf — sin.^ïï  =  cos.2i3;  cos.^2ïï^  |-j-|.cos.4ra; 
and  neglecting,  as  in  [5433a],  the  terras  depending  on  cos.2ro,  cos.4'W,  we  obtain 
[5433i]  ; 

B— ^=a/p.£7.(o5F2)).r/(A.rfro.(l— H.2).(cos.2ra_sin.2^s) 
=  a/p.cZ.  (o5  F2>)  .(Z,x.<Zïî.  (  1  — ,;i2)  .COS.2Z3 

=  a/p.rf.(a5A').rf,a.fZOT.(i— M.2).(l_^2).cos.2w+a/p.f7.(o5/i^).(l-,x2)2.cos.'2w.(/fji.rfw 
=  ia/p.rf.(a5A').(l— (j..2)2.rffii.(/w. 

Substituting  the  integrals 

y^~"rf^==2*,       y!iV-f--)'-^M--  If         [lî54e,/], 

in  this  last  expression,  it  becomes  as  in  [5433']. 

*  (301S)  Substituting  the  value  of  F®  [.5431],  in  fp.d.{a^  F^»),  and  neglecting 
the  terms  depending  on  A",  h"',  h"",  on  account  of  the  equations  [5432],  we  get 
[5434a].  The  integrals  of  this  expression  are  easily  obtained  from  [5433,  5433'],  and,  by 
substitution,  we  get  [5434è]  ; 


[54336] 
[5433c] 
[5433rf] 

[5433e] 


[5433/1 


[5433g] 

[5433A] 
[5433i] 

[5433/1] 


2C—A—B  B—A 

=  (i-O-         ,e,..       +(1— ,x-).C0S.2«.-— -  . 


1  5  * 


[5434a] 
[54346] 


Substituting  this  in  [5430],  and  making  a  slight  reduction,  we  get  [5434].  Multiplying 
this  by  the  second  member  of  [5435],  and  dividing  by  its  first  member  C,  we  obtain 
[5436]. 

VOL.  III.  153 


610 


THEORY  OF  THE  MOON; 


[Méc.  Cél. 


[5434]  (M+m) 


[5435] 


sv 


m  16*  r^.f^f.d.a? 

We  have,  very  nearly,  in  [2962], 


.{(2C— ^— 5).(i-a=)+(jB-J).(I-;^.-).cos.2^] 


c^\l.f:,j.a^, 


therefore. 


Terms  of 

[5436]      ^M+m)._l- 
m 


_ri_ 

1    0 


'f:?.d.a^'  r^ 


[5436 


terras  of  Q. 


In  this  expression,  th    is  the  angle  formed  by  the  principal  axis  of  the  moon, 

,,^    directed  towards  the  earth,  and  the  plane  ivhich  passes  through  the  earthh 

centre,  and   the  axis  of  the  moon's  equator;*    p-  is  the  sine  of  the  earth's 


[5436a] 

[54366] 
[5436c] 

[5436c'] 
[5436(/] 

[5436e] 

[5436/] 
[5436^] 

[54367i] 
[5436i] 


*  (3019)  Tlie  notation  which  is  here  used,  is  similar  to  that  for  the  earth  [5333,5334']; 
and  corresponds  also  with  [2910,3435,  &ic.].  In  defining  the  angle  to,  in  the  original 
work,  the  words,  line  connecting  the  centres  of  the  earth  mid  moon,  are  inadvertently  used, 
instead  of  the  part  printed  in  italics  in  [5436'].  If  we  suppose  the  line  connecting  the 
centres  of  the  moon  and  earth  to  be  projected  upon  the  plane  of  the  lunar  equator,  then 
w  will  represent  the  angle  formed  by  this  projected  line,  or  radius  vector,  and  the  moon's 
longest  axis,  wliich  is  directed  nearly  towards  the  earth  ;  this  axis  being  taken  as  the  origin 
of  the  angle  zi  ;  hence  we  have,  by  supposing  the  angular  and  rotatory  motion  to  commence 
together,  when    -n  =  0  ; 

w:=:  angular  motion  of  this  radius  vector  —  moon's  rotatory  motion. 

Now,  in  [3440,3433/],  v  represents  the  apparent  motion  of  the  earth  in  longitude,  seen 
from  the  moon  ;  and  (p  the  rotatory  motion  of  the  moon  ;  so  that,  if  we  neglect  the  terms 
arising  from  the  reduction  of  v  to  the  plane  of  the  kinar  equator,  we  may  put  v  for  the 
angular  motion  of  the  radius  vector,  and     p    for  the  rotatory  motion  ;  and  by  this  means 

[5436fZ]  becomes, 

w  =  V  —  <p. 

The  differential,  relative  to  the  characteristic  d,  affects  only  the  moon's  co-ordinates  [5363'], 
in  its  relative  motion  about  tlie  earth  ;  and,  as  (p  depends  on  the  rotatory  motion,  we  shall 
get,  for  the  differential  of  the  equation  [5436o-],  the  expression     dT^=dv  ;     therefore, 

d.cos.2w=— 2cZ«.sin.23i,     as  in  [5437,5437']. 
If  we  substitute  the  expression  of    v—(p     [5436ir],  in  [3447c],  we  get, 


VII.ii.§21.]  EFFECT  OF  THE  SPHEROIDAL  FIGURE  OF  THE  MOON.  611 

declination,    seen    from    the    moon,  and    referred    to    the    moon's    equator 
[2909,  3435,&c.].     It  is  evident,  that,  bj  increasing    v    by    dv,   «    increases      [5437] 
by     dv;     therefore,   we  have     d.cos.2OT  =  — 2(/t).sin.2t3     [5436f]  ;     the     [5437] 
differential    symbol     d     referring  only  to  the  co-ordinates    of  the    moon  ; 
moreover,  we  have,  as  in  [5360], 

i2__Q+i.  [5438] 

r 

The  part  of   dR,    relative  to  the  spheroidal  form  of  the  moon,  produces  the 

i-  II       •  •  1      .•       .u  r       *  [5438'] 

followmg  expression,  neglectmg  the  square  of  it-  ;* 

Hence  we  get,  in    to,    or  in  the  moon's  true  longitude,  the  following  term  of 
the  formula  [931]  ;t 


a  =  — M  +  ii.sin.n -f  Sic.  ;  [5436A] 

!/  being  the  moon's  libration  in  longitude  [3464"]  ;  so  that  any  inequahty  which  occurs  in  u, 
may  occur  also  in    -n,    but  with  a  different  sign,  as  in  [5441,  &c.].      If  we  substitute,  in     [5436i] 
[5436A],  the  value  of   u    [3456],  we  get, 


^=-q.  sin.  J  m  i  .  *     /'è .  (^-^-)  +Fl—kc.;  [5436m] 

and,  if  we  change      Q     into     K,     it  produces  the  term  mentioned  in  [5441].  [5436n] 

*  (3020)     The  part  of    Q    mentioned  in  [5425],  and  developed  in  [5436],  produces 
in     R     [5438]  the  following  quantity  ; 

^  f^Yd.a^   1      C  (2C-A-B)              ..AB-A)  ^ 

-^  =  —  -^^y/^^-  -3  •  j    c •  (i— f^  )H Jj (^—n  •  C0S,2îJ  J  .  [5439a] 

If  we  neglect  the  square  of   (x,    as  in   [5438'J  ;   then   take  its  differential   relative  to    d, 
using  the  expression  [5437'],  we  get  [5439]. 

t   (3021)     We   have,  in     Sv    [931],  the  term     -.ff'-^^^;     and,  if  we  neglect 

e^,    putting     a  =  r,     nearly;    also     (j.  =  1,    as  in  [4775"]  ;    it  becomes     3r  .ffndt.dR.     [5Ai0n] 
Now,    nclt    is  nearly  equal  to    dv    [5095];  therefore,  Sv    contains  the  term  3r.ffdv.dR; 
and,  by  substituting  the  value  of    dR    [5439],  it  becomes  as  in  [5440]. 


612  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

The  angle    a    is  always  very  small  [3468,  5436']  ;  so  that  we  may  suppose 
sin.2«=:23i.     Moreover,  from  [3456],  we  find,  that  îj  contains  a  term  of  the 

[5441]     form     —  ^.sin.  \  ^'-X^^'^^^'"^  +  ^\       [5436?«,  «].      This  term,  taken 

with  a  contrary  sign,  represents,  in  [3456,  5436Ht],  the  real  libration  of  the 
moon.     As  it  increases  very  slowly,  it  would  seem,  that  it  ought  to  become 
[5441']     sensible  by  double  integration  :    this  is  the  only  term  of  the  expression  of 
S    which  it  is  necessary  to  notice.     It  produces,  in   6v,   the  term,* 


[5442]  5  ^  _  ^  fjLliÉll'  E  sin   \  V  \  /sS-^r^  +  F 


in  the 
moon's 
longitude 
aris 
from 

spheroidal 
form  of 
the  moon. 


he      The   libration     K .  sin.  \v.l   / ^S^-^  +  F  \    being  insensible, 

suppose,  that  it  amounts  to  a  centesimal  degree.     Moreover,  the  coefficient 
[5443]     y  .  -.  °      '  ^  is  extremely  small.     If  the  moon  be  homogeneous,  it  becomes f 

a^  a 

[5444]      4  ■  V  ^     now,    -    is   the  sine  of  the  moon's  apparent  semi-diameter  ;  hence, 


*  (3022)     Substituting    2^    for    sin.2t3,    in  the  integral  expression  of  ffdv^.sm.2vi, 
which  occurs   in    [5440],  and   then   the  term   of    «    [5441],  we  obtain,  by   successive 
"      integrations,  the  expression  [5442c],  retaining  only  the  most  iinportant  term,  having  the 
divisor     B — A,     arising  from  the  double  integration  ; 

[54426]  ffdv^.sm.2^=  2ffdvK^=  —  2K.ffdv'^.sm.  \  v.  1     /HB—A)  _^  p) 

Substituting  this  in  [5440],  we  get  [5442]. 

t   (3023)     The  moon  being  supposed  homogeneous,  and    p^l,    we  have, 
[5443a]  f^%.d.a^  =  .^;       f;?.d.a^  =  .^;         hence,     j^,  =  -'- 

Substituting  this,  in  [5443],  we  get, 
1544361    ^  .  -  /^^-  =3  4  .  ^  =  I .  sin.3(moon's  semi-diameter)  =  |.(0,0045)«  =0,000024  ; 

and,  if  we  suppose    J5r=lo=54"'  =  3240%    we  shall  get  0,000024.^=0%07,    for  the 

[5443c]  >  rr 

coefficient  of  the  correction  [5442]  ;  which  is  msensible. 


VIl.ii.§21.]  EFFECT  OF  THE  SPHEROIDAL  FIGURE  OF  THE  MOON.  613 

the  product  of    K,    by  this  coefficient,  is  wholly  insensible.     If  the  moon  be 

not  homogeneous,  its  density  must  increase  from  the  surface  to  the  centre; 

then,   this   coefficient  is  yet  less.*      Hence   it  follows,   that  the  preceding     [5444] 

inerjualiti/  of  the  moon'' s  longitude  is  insensible;  and,  that  the  variation  fj-om 

a  spherical  form  does  not  produce  any  sensible  inequality  in  the  motion  in     t^'*'*^] 

lon'^itude. 


As  to  the  latitude,  we  must  observe,  that  (j.  is  the  sine  of  the  earth's 
declination,  seen  from  the  moon  [5437],  and  referred  to  the  lunar  equator; 
moreover,  the  ascending  node  of  the  moon's  orbit  always  coincides  with  the 
descending  node  of  its  equator  [3433]  ;  therefore,  we  shall  have,t 


[5445-] 


S+X.sin.(^l,'  — Oi'  ;  [5446] 

[5446'] 


X     being  here  the  inclination  of  the  lunar  equator  to  the  ecliptic.     Hence  we 
get,t 

*  (3024)     Changing     R     into     a,     in  [277']  and  miiltiplj'ing  by     ^,     we  get 

being  less  than  its  value     a^,     corresponding  to     p==l      [5443a]. 

t  (3025)     It  is  found  by  observation,  that  the  descending  node  of  the  lunar  equator  always 
coincides  with  the  ascending  node  of  the  lunar  orbit  [3433]  •  and  the  inclination  of  the  lunar    [5446a] 
orbit  to  the  ecliptic  is  nearly  equal  to     -/     [.5400],  also  the  inclination  of  the  equator  to  the 
ecliptic  is     X     [5446']  ;  therefore,  the  inclination  of  the  lunar  orbit  to  the  lunar  equator,  is 
nearly  equal  to     v+X  .     Now  from  [5383],  we  find,  that  the  moon's  latitude,  or  the  angular     [544("iR] 

elevation  of  the   moon  above  the  ecliptic,  is  nearly  represented   by     s  =  y.s'm.f^v ê)  • 

hence  the   coiTesponding    angular  depression   of  the    earth,  as    seen    from    the   moon,    is 
—'y.sm.(gv — Ô)  ;     and  it  is  evident,  that  by  changing  the  inclination    7  into    y+X  [54404], 

we  get  the  angular  depression  of  the  earth  below  the  lunar  equator     — (y+X).sin.(i?-i) 6)  . 

This  may  be  put  equal  to  its  sine     /a  ,     and  by  using  the  value  of    s     [544Gc],  we  "-et 

l^  =  —  (v+>^).sïn.(gv—6)^  —  s  —  \.sm.(gv—ê)z=—  \s-{-\.sm.{gv—ô)  I;  [5446e] 

vsrhose  square  is  the  same  as  [5146]. 

X  (3026)    The  partial  differential  of  fj.a  [5446],  relative  to  s,  being  divided  by  2ds,  gives 

the  first  of  the  expressions  [5447]  ;  substituting  in  this,  the  value     sm.(gv—ê)=-     [5446cl    r...^  . 

/  [.5447a] 

we  get  the  second  form  of  that  equation. 
VOL.  III.  154 


[544Ce] 
[5446^^] 


614  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

/c'a               ,            •      ^              N          (>^+7) 
[5447]  '^  •  i  rf^  ]  ""  *  +  ^  •  ^'"-(e"*^  —  ")  "=  -^ •  *  Î 

therefore,    the    spheroidal    form    of  the   moon,   adds   to    the    expression    of 

[5447']      —  -i-  .  ( -^  )  ,     in  the  equation  [4755],  the  term* 

[5448]  ./A4i;4.(-_±Z)...52_t^+^.eos.2.|. 

=     f^p.d.a'     r^  y  I  C  ^       C  s 

[5448]      Now,  as  we  have  very  nearly,    cos.2i3  =  1,  it  adds  to  [4755],  the  quantity,t 

[5449]  A  ,  fll^-^^  .  i     ^^±^  .  i^  .  S  ^  term  of  [4755]. 

It  is  evident,  from  [5397 A;,  /],  that  this  term  adds  to  the  motion  of  the  node, 
the  quantity, Î 


*  (3027)    Substituting,  in     — —   .  \-^\     [5447'],  the  tenus  of  ^,   given  in  [5436], 
we  get, 

[5448a]  '        /dQ\  s     .'sil .  u,.     —  ]  .  ( .  cos.  2  m  >  : 

[544861     substituting    the   last  of  the  expressions  [5447],  we  get  [5448];  observing  that     A^     and 
M-',     are  nearly  equal  to     a ,     or     r     [4937?i,&ic.]. 

t   (3028)     Since     «     is  very  small,  we  have  nearly     cos.23J=1;     hence  we  get, 

9C—A—B      B—A                   2C-A—B    ,  B—A       ^    C—A 
[5449a]  2L_£_Ji  _^  -D_^  _  ^^^^^  =  -^^ \-  —^  =  2  .  -^   ; 

substituting  this  in  [5448],  we  get  [5449J. 

X  (3029)     Substituting, in  [5449],  the  value  of    s     [5446c],  it  produces,  in  the  equation 
[4755]  or  in  its  development  [5347/],  the  quantity, 

r/p.^/.aS     1      (X+y)      (C—A)  .  . 

[5450a]  A  .  ■'^y—.  -,  .  ^^^^  •  —-JT-^  •  7  •  sm.{gv—à)   . 

[54506]     This  is  similar  to  the  term  which  is  computed  in  [5397A:]  ;  and,  by  making  the  calculation  as 
in  [5397fc,Z],  we  find,  that  the  preceding  term  [5450«),  produces  in     p",     the  term, 

f.y.d.a^     1      M-y     C—A  _ 
[5450c]  ^P"  ""  '  '  f^Y^Ta' '  '^^  '     y     ■        C     ' 

„     and  the  corresponding  motion   of  the   node,  computed   as  in  [5397^,/],  is     W'-^     as  in 
[5450a 1 

[5450]. 


Vll.ii.'^Si.]     EFFECT  OF  THE  SPHEROIDAL  FIGURE  OF  THE  MOON.  616 


MoLioa  of 
tlie  nodoa- 


/■'p.d.«'         t>         C^-hy)        (<^ '^)  c    ,.  risingfiom 

1 .  1^— -3  •  -o  •    -^-^  •  —-r      =  ^^^"^  °^  ^^  •  t^^5°l 

^      L^p .  a. a"*      r-  7  C  iho  sphe 

-'^  "^  roidal fig- 

ue u  of  tbo 
/^       j^  niooD. 

In  [3545]  we  have  *    — x—  =  0,000599  ;     hence    it   is   evident,  that   the      [5451] 
preceding  quantity  is  insensible. 

We  find,  likewise,  that  the  spheroidal  form  of  the  moon  adds  to  the  term 


— i 


(  j^)     of  the  equation  [4755],  the  term, 1  ^  [5452] 


_  4  .  ''-Î-!— — -  .  -  .  ^^ -— !— ^  .  s  =  term  of  [47551. 


[5453] 


*  (3030)     We  have      ^      =  0,000599     [3545]  ;    hence    it    follows,  that     C     is     [5451a] 
nearly  equal  to     .^;     and  we  may,  therefore,  change     Jî     into     C,     in  the  denominator  ; 

by  this  means  we  shall  get     ^""^  =  0,000599    [5451].     Moreover,  X  =  1''29"'  [5446'] 

[54516] 
[3434]  ;     7 1=5'' 8""  50'     [5117]  ;  and  if  we  suppose  the  moon    to  be  homogeneous,  we 

6       1      r^p  d  a^ 
shall  have      -  .  ^  .    °       '  3  =  0,000024     [54436].      Substituting    these    in    [5450],    it    i[545it] 

becomes,   0,00000001. d     nearly.     Now,  in  one  lunar  month,     j;  :^  1296000';  substituting 

it,  we  get     0-,01  ,     for  the  motion  of  the  node  in  a  lunar  month,  arising  from   this  cause.     1  l 

This  is  wholly  insensible. 

t   (3031)     Substituting  in  the  term  of    Q   [5436]  the  value  of    r=-    nearly  [4776]      [545301 

we  get  [54526].     Neglecting     (a,     on  account   of  its    smallness,  and  putting     cos.2«=l 
[5448'],  we  get  [5452c], 

j^'-^.d.a^      ,    C  2C—A—B     ,  „,       (B—A)    ,  > 

^ = " •  %:d-:è ■''■{  —c—  ■  (^ - -')  +  S-- ■  ( '--^)--2.  j 


[54526] 
.  u"  .  ^ 77-^ '-.  [5452c] 


//p.d.a^      3    (C-2A+B) 


This  gives, 


U;  =  "  •  l^Zd:a^  ■  "   •  r ■'  [5452rf] 


and  by  multiplying  it  by     —  —  ;     using  also     h^  =:  a  ,     u'^  =  a  =  r     nearly  [4937n], 
we  get  [5453]. 


616  THEORY  OF  THE  MOON  ;  [Méc.  Cél- 

This  adds  lo  the  motion  of  the  noae,  the  term,* 


l^I  -  -.-  ,  ei-^,  .  -.-  .  i^?#+^  =  tern,  of  . .  ; 


1   0 


a  quantity  which  is  wholly  insensible. 


..._.  ,  *  (3032)  The  expression  [5454]  may  be  derived  from  [5453],  in  the  same  manner  as 
[5450]  is  from  [5449]  ;  namely,  by  changing  «  into  |u  .  To  estimate  roughly  the  value 
of  the  expression  [5454],  we  may  observe,  that  in  the  case  of  homogeneity,  we  have, 

[54546]  __=_;  ^^=7T     [3570]. 

Their  sum  is, 

;,«„  'C:^='^;=i.  (_£=!>  =0,001     [545,.l,neaH,; 

hence  it  is  evident,  that  the  term  [5454]  is   insensible,  Hke  the  corresponding   term  [5450] 
which  is  computed  in  [545l£/]. 


VII.iii.§22.]  ACTION  OF  THE  PLANETS.  617 


CHAPTER    III. 

ON  THE  INEaUALITIES  OF  THE  MOON,  DEPENDING  ON  THE  ACTION  OF  THE  PLANETS. 

22.     It  now  remains  to  consider  the  action  of  the  planets  upon  the  moon. 
We  shall  put, 

P  —  the  mass  of  a  planet  ;  [5455] 

X,Y,Z=  the  rectangular  co-ordinates  of  the  planet,  referred  to  the  centre  of     [5455'] 
the  earth  ; 

/=  the  distance  of  the  planet  from  the  earth's  centre.  [5455"] 

Then,  it  is  evident,  that  the  action  of  the  planet    P,   îvill  increase  the  value 

of    Q    14:1 5G],  by  the  quantity  *  Terms  of 

_   _P.(.X+yY+.Z) P_ _^  .  3^' 

or,t 


[5456o] 


*  (30.33)  The  disturbing  force  of  the  planet  P,  upon  the  moon,  in  her  relative 
motion  about  the  earth,  is  computed  by  the  same  differential  formulas  which  are  used  for  the 
disturbing  force  of  the  sun.  We  must,  in  this  case,  change  the  mass  m'  of  the  sun 
[4757"],  into  that  of  the  planet  P  ;  and  the  co-ordinates  x,  y',  z'  of  the  sun  [4758'],  [54566] 
into  those  of  the  planet  X,  Y,  Z  [5455']  ;  by  which  means,  the  distance  r'  of  [5456c] 
the  sun  from  the  earth  [4759'],  changes  into  /  [5455"],  which  represents  the  distance  of 
the  planet  from  the  earth.     Making  these  alterations  in  the  two  last  terms  of     Q     [4756],     '■  ■' 

we  obtain  the   part  of     Q     [5456],   upon   which  the  disturbing  force  of  the  planet     P     [5456e] 
depends. 

t  (3034)     The  development  of  [4774]  is  given  in  [4775],  and,  if  we  multiply  this  by 

VOL.  III.  155 


618                                              THEORY  OF  THE  MOON  ;  [Mée.  Cél. 

[5457]  Q    =    J j^+iP-^       ^/J       ^    +^C. 

Let 

[5458]     X',   Y',  Z',  be  the  co-ordinates  of  the  planet  P,  refered  to  the  sun's  centre  ; 
[5458']      y.'^    y'^    ~'^  ^i^g  co-ordinates  of  the  earth,  referred  to  the  sun's  centre  ; 

then  we  shall  have, 
[5459]  X=X'—x';         y^Y'— 7/';         Z  :=  Z'—zf. 

Hence,  the  function  [5457]  becomes,* 

C5460]  ,2    =    ^  _  J^+  I  p.  (£'~+Y',+  Z'y. '-„'-. ^r  +  j,„. 

[5461]     ff^g  shall  take  the  ecliptic  for  the  fixed  plane.,  which  makes    2'=  0,    and,  we 
shall  put, 

Symbols.  ■*■ 

[5462]     R  =  the  radius  vector  of  the  planet    P,    projected  upon  this  plane  ; 

[5463]     U  =   the  angle  formed  by  the  projection  of  the  radius,  and  by  a  fixed  right 
line,  taken  in  the  same  plane  ; 

[5464]      «S  =  the  tangent  of  the  heliocentric  latitude  of  the  planet    P  ; 

[5465]      r'  =  the  radius  vector  of  the  earth  ; 

[5465']     v'  =^  the  angle  formed  by  the  earth's  radius  and  the  fixed  line. 

Then,  we  shall  have, 

[5457a]    P  ;  changing  also  x',     y',     z ,     r' ,    into    X,      Y,     Z,    f,  respectively,  as  in  [5456è-c?], 
we  get, 

^''"''^  vÂx^mT^^^R^^-^7+ ~p +" p ^ 

Substituting  this  in  [5456]  ;  reducing  and  neglecting  terms  of  the  order     Xf-^,     or    /~^  ; 
r5457c]    we  get  [5457]  ;  observing,  that  the  terms  depending  on  the  first  powerof  {xX-\-yY-\-z  Z), 
mutually  destroy  each  other. 

*    (3035)      Substituting,    in    [5457],   the  values   of    X,     Y,     Z     [5459],  we   get 
f^*^°"l    [5460]. 


VII.  iii.'§,22.] 


ACTION  OF  THE  PLANETS. 


619 


*  /  =3.  y'R^(  I  -^SS)+r'^—2Rr'.  cos.(U—v').  [5466] 

Hence,  the  part  of     Q,     relative    to  the  action   of     P     upon  the    moon, 
will  be,t 


*  (3036)  111  the  annexed  figure,  S 
is  the  place  of  the  sun  ;  E  that  of  the 
earth  ;  P  the  place  of  the  planet  ;  and 
P'  its  projection  on  the  plane  of  the 
ecliptic  SMP'.  Then,  z'=0  gives 
Z  =  Z'  [5461,  5459]  ;  and  the 
rectangular  co-ordinates  of  E,  P,referred 
to  the  sun,  are  SF  =  x'  ;  FE  =  y'  ; 
S31  =  X'  ;  31P'=  Y'  ;  P'P^  Z'  ; 
and,  by  drawing  EX  parallel  to  SM, 
v^ehzveEN^X;  NP'=Y;  P'P=Z;  ^^ 
SE=r';       SF^R;       EP=f; 

angle  FS£  =  »';  angle  F5P'=  C7 ;  tang.  P5'F=S.  Fron  these  symbols  we  easily 
obtain, 

X'^iJ-cos.^';  Y'  =  R.sm.U;  Z' =RS; 

.r' =r'.cos.i;';     -  i/' =  ?•'.  sin.t;' ;  5;'=  0. 

The  values  of  the  co-ordinates  of  the  moon  x,  y,  z,  and  of  the  radius  r,  referred 
to  the  earth's  centre,  are  given  in  [4776 — 4779].  Now,  the  distance  EP=f,  is 
evidently  equal  to  \/{X~-\-Y~-\-Z^)  ;  and.  if  we  substitute  the  values  [5459],  we  get, 
by  development, 

/=  ^{X^+Y^+Z^-)  =^l{X'-xr+{Y'-^f+{Z'-zy\ 

=  S/{{X'^+Y  '^+Z'2)+(x'2+y2_)_^'a)_2(xV+  Y'y'^  Z  V)  \. 
Substituting  in  this,  the  values  of 

X'2-|-F'2-]-Z'2=  SP2=iJa.(l_|_Sf2);  /2  =  y2_^y2+V2; 

X'x'+y'y'+Z'2'  =  JfJr'.{cos.f7.cos.i)'-fsin.f7.sin.«'|  =:Rr' .cos.{U—v')  ; 
it  becomes  as  in  [5466]. 

t  (3037)     Substituting  the   values    [5466/,  4776—4779],    in    the  first  members  of 
[5467a,  è],  and  making  the  usual  reductions  by  means  of  [24]  Int.,  we  get  the  second 


[54661] 
[54666] 
[5466c] 

[5466rf] 
[546Grf'] 
[5466e] 
[5466e'] 

[5466/] 

[5466^-] 


[5466A] 

[5466t'] 
[5466*] 


620  THEORY  OF  THE  MOON  ;  [Méc.  Ce). 

or,  by  neglecting  the  square  of  S* 
[54681        O   =    -  4-  ^"-(1-2^')   I  3  p   \ ^'- cos{2v-2U)-j-r'"-. cos{2v-2v')-2Rr'.cos{^v- U-v')  j 

J- 3  P    -R-s-S'.f fi.cos.(iJ  —  U)  —  i-'.cos.{v—v')l    ,    0^ 

P 

As  the  term    —    does  not  contain  either    u,    v,    or    .9,    it  will  not  enter 

[5468']  / 

P 

into  the   equations   [4753—4755].       The  term      j-Y~f3      gi^es,     by   its 


members  of  these  expressions  ; 

R  R 

[5467aJ  X'a;  +  r'y4-Z'r  =  - .  jcos.L^.cos.t)+sln.t^.sin.u  +  &  |  = -.  [cos.(f7— it)4-&|  ; 


[54676]  — xx  —  yy' — zz  =  —  —  .|cos.i)'.cos.i;-j-sin.t;'.sin.i)^  = .cos.(t) — ti'). 


l-t-ss 
[5467c]     Substituting  these,   and     r"~  = -^      [4776],  in  [54G0],  we  get  [5467]. 

*  (3038)     If  we  develop  the  numerator  of  the  last  term  of  [5467],  and  neglect  the 

square  of     S,     we  shall  find,  that  the   terms  containing  the  first  power  of     ^S'     are  the 

same  as  in  the  second  line  of  [5468].     The  remaining  part  of  this  numerator  of  [5467]  is 

[546861    ^^  ™  ^^^^  ^'"^^  ™^"''^^'"  °^  [5468c]  ;  and,  by  developing,  using  [20]  Int.,  it  becomes  as  in 

[546Srf]  ;  and,  by  the  substitution  of    /^     [5466],  we  finally  obtain  [5468e]; 

\E  .CQS.{v—U)—r' .cos.{v—v')\^ 

[54()8c]      ^JJ2_j.os_2('^_J7)_^/2.cos.2(^_,„')_Oiî,.'.coS.(y— C/).cos.(^— /) 

[5468(/]    =J-.{7?2+r2— 2Rr'.cos(t/-u')}+i|iî^cos(2i;-2C7)+7-'2.cos(2y-2ii')-27î/-'.cos(2f-f7-i/)| 
[5468e]     =^-f-+h  { R^.cos.{2v—2U)+i-'^.cos.{2v—2v')—2Rr'.cos.{2v—U—v')  I . 

The  part  of  this  expression  between  the  braces,  being  substituted  in  the  numerator  of  the 
last  term  of     Q     [5467],    produces  the  third  term  of  [5468  line  1]  ;  the  otlier  part  of 

è/2  SP 

[5468/]     [5468e]is     iP  ;     which  gives,  in  [5468],  the  term     i -P- ".^T  =    4^^575-      Connecting 

p  I 2 2^2) 

this  with  the  second  term  of  [5467],  which  may  be  put  under  the  form        '„     —  ,     we 
[5468g-]     ^gj    ^^,     as  in  the  second  term  of  [.5468].     Finally,  the  first  term      j     [5467],  is 

the  same  as  in  [5468]  ;  and  we  may  observe,  as  in  [5468'] ,  that  this  term  may  be  neglected  ; 
for,    /    [5466]  does  not  contain     r,     s,     v;     and  its  partial  difierentials,  relative  to  these 
[5468/t]     quantities,  will  vanish  from  the  general   formulas  [4753—4755],  which  are  used  in  this 
chapter,  in  finding  the  perturbations. 


Vll.iii.  ^2-2.]  ACTION  OF  THE  PLANETS.  621 

development,  a  function  of  this  form,* 
JL.  =  il-.[^^('')+J(i).cos.(C/— i)')+^'".cos.2(C7— tj')+^c.}=terms  of  Q.      [5469] 

Hence,  the  term     —   -r^  .  ('y^j,     of  the  equation  [4754],  produces  the 
following  function  ; 

-^.^M"''+-4<'>.cos.(t/'-2;')+-4="-cos.2.(C/-w')  +  Sic.J=termsof  -~.('l^\.      [5470] 

and  it  is  evident,  from  ^9,  10,  that  there  will  result  from  it,  in  the  expression 
of     au,     the  quantity, f 

p 

*  (3039)     If  we  substitute  the  value  of  /    [5466],  in  the  term    T-^-^g,     of    the 

expression  [5468],  we  may  develop  it,  in  the  usual  manner,  in  a  series  of  the  form  [5469]. 

This  part  of    Q     gives,  in    —  T^"  •(/")'      ^^^'^   expression    [5470];    as    is  evident  by     [54C9o] 

2Ps3 

differentiation.     The  next  term  of  [5468]  is     —      ^       ;    and,  as  it  is  of  the  order  s^,  in 

comparison  with  [5469],  it  may  be  neglected.  The  next  terms  of  [5468]  contain  the  angle  [.54696] 
2v  ;  but  these  quantities  do  not  produce,  by  integration  in  nt-\-s  [5474],  any  term  of 
importance,  arising  from  a  small  divisor  like  i — m.  The  same  remark  may  be  made 
relative  to  the  terms  of  [5468]  containing  v — U,  v — v' ;  and,  as  they  are  also  multiplied  [5469c] 
by  the  small  quantity  Ss,  they  may  be  neglected.  Moreover,  a  little  attention  will  show, 
that  the  substitution  of  Q  [5468],  in  the  four  first  lines  of  [5081],  will  produce  no  terms 
of  the  like  kind,  depending  on  angles  having  a  small  coefficient  except  they  are  multiplied 
by  quantities  of  the  order  of  the  excentricities,  Sic;  and,  by  neglecting  such  quantities  as 
in  [5486',  &1C.],  we  shall  find,  that  the  first   term  of  importance   is  that  in  [508Iline  5], 

which  gives  in    fit    the  term     —  -^ — .2a5u.     Multiplying  this  part  of    Jt    by     n  =  ~ 

[5092c],  we  get,  in    nflt,     the  term     7idt  =  — dv.^aSu;     which  will  be  used  hereafter.  [5469/] 

t  (3040)     Substituting     U=iv     [.5463,5472],     v'=:mv,     h^^a,    m  =  a"'   [4937m],     [5470a] 
in   [5470],    and   then    connecting   it  with    the   two  terms -X-u     [47541   and  with 

the  term  of  the  same  equation,  which  is  developed  in  [4908  line  1]  ;  namely, 

2 
3m 
—  -ir—.ahL  =  —%m^M     r5082A'],  nearly: 

2a,  "•  i'  :  '  [547051 


VOL.  III.  156 


622  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

TKAji^            -  r.  1  ^A^'K COS. (i-m).v  ,  A^-\cos.2(i-ni).v     A^^^Kcos.SU-m^-v  ,  „      )  „     , 

[5471]       — iPa^.  } i '- !^ i i L-  4-&C.  V  =  terms  of  aôu  ; 

i   beins'  the  ratio  of  the  mean  motion  of  the  planet    P  to  that  of  the  moon. 

[5472]  a  J  J  r  J 

Hence  arises,  in    ndt    [5081,  &c.],  the  function,* 
[5473]       p^3j^ ,     ,       ,    ,      ,.    \3+,      3    2  Ar      N2+ 1— ^    2  or     \o+&c.  [  =  terms  of  ndt  ; 

conseqenily,  we  have,  in     ni+s,     the  following  expression  ; 

it  becomes, 

[5470c]         0  =  — +  M  +lPa^AiA^'>^+A'-^\cos.{i—m).v-irA^'''.cos.2(i—m).v-i-k.c.\—iin^Su. 

Now,  supposing  any  term  of    u,     or     Su,     to  be  represented  by, 
l^470rf]  ûu  =  B^"\  COS.  n.{i  —  m).v, 

and  substituting  it  in  [5470c],  we  find,  by  retaining  only  the  terms  depending  on  this  angle, 
and  dividing  by     cos.?i.(i — m).v, 
[_5470e]  0  =  —  «2.(i— »i)2.B('0-}-5('')-|-iPrt2.^u)_3,B2_5(7.). 

Hence  we  get, 

—iPoS.^i») 
[5470/]  -B*"'  =  - — :^ --. r^   ; 

and,   the  term    of    a^u     [5470i],   corresponding    to    that  in    [5470c],    which  contains 

^''",     is, 

„  1  -4''''.cos.7i.(i— m).v 
[5470^:]  ahu  =  —\Pa\  ,_,  o_  o— r„ 


a 


1  — §m^ — 11?. [i — ?n) 

From  this  formula  we  may  easily  deduce  any  term   of    a&u     [5471],   from  that   which 

depends  on  the  same  angle     n.{i—m).v     in  [5470c],  by  multiplying  the  term  of  [5470c], 
[5470ftj  _^ 

depending  on     ^"'',     by  the  factor      i_|^a_,i2  (j-_„j)2- 


*  (3041)     Substituting,  in     ndt  =  —dv.2aSu   [5469/],  the  value  of  a<5M    [5471],  we 
[5473a]     get  [5473],  whose  integral  gives   [5474].     Now,  from    [5475],  we   have     a  = -;;^  ; 
substituting  this  in  [5474],  we  get  [5476]. 


VII.iii.^22.]  ACTION  OF  THE  PLANETS.  623 

Pa'    QA^^\sm.{i—m).v     iA'^Ksm.2{i-m).v  AA^^\s\n.3{i-m).v 


&c.  [  =  terms  of  ?it+ f.       [5474] 


Now,  we  have     — ^  =  m^    [5374rt — 6]  ;    m'  being  the  sun's  mass.  Hence,      [5475j 
the  preceding  function  becomes, 

.7)1  .a     c^i).sin.(î"-m).i;  ,  à^'->.sin.2(?'-?»).«  ,  M'^'-sin  3(i-m).v  } 

— A Î: i !^ '- \-- ^ '- — h&c.  >  =  terms  of  7!<+«.         [54761 

In  the  case  of  a  'planet,  inferior  to  the  earth,  ive  have,  by  putting    a  for  the 

ratio  of  the  mean  distance  of  the  planet  from  the  sun,  to  that  of  the  earth  from     ^  ^'^ 

the  sun,  and  retaining  the  denominations  of  chap.  vi.  of  the  sixth  book,* 

a".  J<"  =  b'^  ;         a'\  J'^'  =  b^  ;         a".  A'-'^  =  b'^  ,     &c. ;  [5478] 

2  2  2 

which  changes  the  function  [5476]  into  the  following  ; 

Terms  of 

~-;.m^    \  b  g. sin. (^i-m).v     |6„.sin.2(»-7«).i'     ib  ^. sin. S {i—m).v  /  ivomtho 

^ i   /.     o    ,•        V'+.     ^■^     2    AT     ^2+1     ^■^     2    Q/^l3+^"-  I  =   *"'"'    °^     "'+-    ;         f5479] 

I — m   I  l-^mr-h-m)-     1 — ^m-'-4  (i-mY     1 — mr-dn-mY  ) 

direct  ac- 
tion of  an 

in  which  ive  may  take,  for    (i — m).v,    the  mean  longitude   of  the  planet,    pllne?.' 
minus  that  of  the  earth. 

With  respect  to  a  superior  planet,     a     denotes  the  ratio  of  the  mean  distance     [5479'] 


*    (3042)      Changing    a,     a'     [956],   into     R,     r'     [5462,5465].  respectively,    in 
order  to  conform  to  the  present  notation  ;  also,  the  angle     n't — n^-f-s' —  s,     into      U^v',     [5478a] 
it  becomes,  by  neglecting,  for  brevity,  the  consideration  of  the  excentricities, 

\m-i-r'^-—<2Rr>.cos.{U—v')\-i=:^^-S..B'-^cos.i.{U—v').  [54784] 

If  we  neglect     S-,     the  first  member  of  this  expression  becomes  equal  to    f~^    [5466]. 

p 
Multiplying  this  by     rr  >   we  get, 

4^3=     ^.\i^.B^'\oos.i.{V-v')\.  f5478c] 

Comparing  this  with  the  development  in  [5469,956'],  we  get     £<''=  ^'''.     Substituting 
[1006],   and  multiplying  by    f^'^    we  obtain     a^.A'^'~>==b3  ,  as  in  [5478].    Substituting     [5^^^^^ 
these  in  [5476],  we  get  [5479]. 


624  THEORY  OF  THE  MOON;  [Méc.  Cél. 


of  the  earth  from  the  sun,  to  that  of  the  planet  ;  so  that  we  have 


* 


(l)  (2)                                                                           (3) 

[5480]       «'3.  J(')_al6,       ;  o'^  ^(^' =  a=.è^      ;                a'\  A^^^  =  ^\  h  ^  ;  he. 

2  2-2 

Terms  of 

f/oJr''      This  changes  the  function  [5476]  into  the  following  form, 

the  direct 

planet?""     —■1)^0?  S     ^    .  sin.ft— m).w  4  6,  .sin.2(i— 7n).v       Ih      e,mâ[i—m).v               }                           (^) 

m               <â  .A                            ,*                            ,„>„.. 


These  are  the  only  sensible  terms  ivhich  can  result  from  the  direct  action  of 
the  planet   P    on  the  moon. 

But,  the  sun's  action  upon  the  moon  may  render  sensible,  in  the  motion  of 

that  satellite,  the  perturbations  of  the  radius  vector  of  the  earth'' s  orbit,  arising 

Indirect     fiom  tlic  ttctlon  oftlic planct  P  upon  the  earth,  and  may  produce,  in  the  moon's 

"fanets       motious,  incqualitics  of  the  same  order  as  those  we  have  just  considered.  To  prove 

[5482]     it,  we  shall  consider  the  term        '    ^     [4866],  which  is  a  part  of  the  equation 

h-'        P 

[5483]      [4754].     We  shall  suppose     — =^  ~.  K.  cos. Q2'n't—^n't+B),     to  be  any 

,5,-' 
[5484]      term  of    — ,     arising  from  the  action  of  the   planet     P     upon  the  earth  ;t 

'  n"t    denoting  the  mean  motion  of     P,     and     n't     that  of  the  earth  ;    the 

corresponding  term  of    -7-     will  be, 

[5485]  ^=  —-,.K.  COS. œ'n"t—^n't+B). 

urn 


*  (3043)     The  equation  [5478d]  holds  good  for  a  superior  planet,  by  merely  changing, 
3 
in  the  factor     a'",     the    quantity     a',     corresponding  to   the    earth's    distance  from  the 
[5480a]  „, 

sun,  into     -      [5479],  which  represents  that  of  the  superior  planet  from  the   sun  ;    by 

which  means,  it  becomes, 
[54806]  ©'-^'"^^r         °'         a'^A^^^  =  a?.b'^,       as  in  [5480]. 

Substituting  this  in  [5476],  we  get  [5481]. 

f  (3044)     This  form  is  the  same  as  is  used  in  various  places  ;  as,  for  example,  in 


VII.iii.§22.]  ACTION  OF  THE  PLANETS.  625 

^       '3 

Hence,  the  term       '^   .^     produces  the  following  ; 


Q  p  ,,'3 

__  ''1:1.  .  K .  COS.  œ.'n"t—^n't+B).  [Term  of  4754]  [5486] 

Sr' 

If  loe  consider  only  those  inequalities  of    —,     lohich  are  independent  of  the     [5480] 
excentricities  of  the  orbit,  and  represent  them  by  the  series* 

P  or' 

—  .{X(''.cos(n''<-«V+s''-.'')+*^^-'-cos2(ft'V-ri7+£''-5')+£''3).cos3(n'7-n7+s''-£')+&'=|=termsof_;       [54871 

m  a 

f  fO 

lit  tU 

the  term    -7^—5    Avill  produce,  in  [4754  or  4961],  the  function,! 

—  ^  •-, •  i  K^'\eQS.{i-m).v+K''Kcos.2{{-m).v-\-K'-^\cos.3(i-m).V'}-hc.  j  ;  [Terras  of  4754]       rg^gg-, 
whence  results,  in     a^u,     the  function, 

"l~-,7'  1 1  -|TO3_(i_„,)2+i_3„,a_4(i_,„p+j-:zp-9_c,(i_„,p+  «^c.  ^  _  terms  of    atSw  .  ^g^gg-j 

This  gives,  in     nt-\-s     [5095],  the  following  terms  ; 


[1023,  4306,  4308,  &.C.].     Now  we  have,  very  nearly,  in  [4777e],     u'=-;      and,     the     [5486a] 

differential  of  its  logarithm  gives, 

6u'  or'  Sr 

-;7  =  —  —  =  —  ^  ,     nearly  ;  [54866] 

substituting  this  in  [5483],  we  get  [5485].     If  we  vary     u',     by  the  quantity     (5)*',      it 

J  .        m'.  !i'3 

produces,  in  ^  ,     the  term, 

3  m'.  It' 2.  fa'  3m'. u'^     iu' 

2A,3.u3        ~    2^2;^  •  ~^  '  [5486c] 

Su' 
and,  by  substituting  the  value  of    — ;-     [5485],  it  becomes  as  in  [5486]. 

*  (3045)     The  form  assumed   in    [5487],  is  the  same  as  that  in  [4306  lines  9—1 1]  ; 
decreasing  the  accents  on    n'",    n",    i'",    s",  &ic.  by  unity,  so  as  to  conform  to  the  notation     [5487a] 
here  used. 


t  (.3046)     Substituting,  in  [5486],  the  values     u  =  cr^     u'=a'-\     h^=a[4937n], 
also     ^=^,      [5475],  it  becomes,  [54876] 


a'3  m' 

VOL.  III.  157 


planet. 


Action  of 
Venui. 


[5491] 


(0) 
2 

9,992539  ; 

(1) 
2 

8,871894; 

2 

:  7,386580  ; 

*!"= 

5,953940 . 

626  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Tonna  of 

nt+e        *    3ma  P    C    K^'Vm.ii—viU    ,    iK&'>.sm.2{i—m).v   ,    lsKS3).sin.3{i—m).v     ,     „       )  (^) 

[54901 <  ^ —  -\ ^ r — — h  &c.  >  =termsof  nt+e. 

illing  '  i_mm'    U-|m2_(i— m)a^l— am2-4(i— m)3^1— fm-2— 9(i-m)2  ^  5 

IVoni  ilio 

Mtimofa  This  function  is  of  the  same  order  as  that  which  results  from  the  direct  action 
of  the  planets  upon  the  moon  [5479,5481].  fVe  shall  noio  compute  these 
several  inequalities  for  Venus,  Mars,  and  Jupiter. 

Relatively  to  Venus,  we  have,  in  [4126,4132], 

a  =  0,72333230  ;  1 

2 
S 

4 

6 

Hence  we  deduce,  by  means  of  [974],f 


[5488a]  —  ï  •  W  •  K.cos.{?!i,:'t-^nt+B)  ; 

ir' 
which  is  the  same  as  the  product  of  the  assumed  value  of     —      [5483],    by   the  quantity 

[548861 ^.     Therefore,  if  we  multiply  the  assumed  value  of    — -  [5487] ,  by  the  same  factor 

2a  a'     ■•  •' 

—      we   shall  obtain  the  corresponding  expression,  which  arises  from  the  variation  of 

2a 

[5488c]    '"'•"'   ,     as  in  [5488].     This  term  forms  a  part  of  the  equation  [4754,  or  4961]  ;    and,  we 

may  find  the  corresponding  part  of    k,    or  rather  of    ahi,    as  in  [5470^*,  A],  by  multiplying 

a 
any  term  of  [5488],  depending  on     K'^"-\coi.n.{i—m).v,     by     —  j_3„j2_,j27/;_„;)2    5 

hence  we  obtain  [5489]. 

*  (3047)     Substituting  the  terms  of    a&u     [5489],  in     ndt  =  —  2dv.a5u     [54G9/], 
[5490a]    and  integrating,  we  get  the  terms  of    nt+s   [.5490].     We  may  remark,  that  i.i  iLe  original 
work,  by  a  typographical  error,  the  terms  of  [5490],  are  made  to  depend  on    cos.(;'— ?«).r  ; 
[.54906]    C0S.2. {i—m).v,     &c.     instead  of    s\n.{i—m).v;     <i^2.(i— m).«',   &c. 

t   (3048)     Putting     «  =  f,     in  [974],  and   then,  successively,     i  =  0,     i=\,     we 
get; 


vu.  iii.  §  22.]  ACTIOA  OF  THE  PLANETS.  627 

(0) 

6^  =  85,77422  ;  [5492] 

b'J^=^  83,40760. 

By  observations,  we  have     z—îh  =  0,0467900  ;*     therefore,  by  supposing,     [5492'] 
as  in  [4061, line 3], t 


[5493] 


Direct  ac- 
tion of 
Venus. 


[5494] 


P J 

m'  ~  3S.3130  ' 

we  find,  that  the  function  [5479],  reduced  to  seconds,  becomes, 

+  0%577273.sin.(z— m).D  1 

+  0',241919.sin.2.(i— /«).«  [Terms  of    nt+£]  2 

+  0%131463.sin.3.(i— m).i;  3 

What  we  have  here  represented  by     —,     is   denoted   by     Sr'',     in   [4306, 
line  l,&c.],  and  we  have,  in  that  article,  by  means  of  the  action  of  Venus, 


(0)  <1)  (I)  (2) 

b,  -= ;  b,  ^ ? ^  .  [5492a] 

With  these  formulas,  we  may  compute  the  values  [5492], by  using  the  expressions  [5491]. 

*  (3049)     If  we  use  the  same  notation  as  in  [4077],  we  shall  fiod,  that  the  mean  motion 

of  Venus,  in  comparison  witli  that  of  the  earth,  is  represented  by     — .     Multiplying    this 

by     m  =  0,0748013     [5117],  which  expresses  the  ratio  of  the  sun's  mean  motion  to  that 

of  the  moon,  we  get  the  expression    of    i     [5472],  or  the  ratio  of  the  mean   motion  of    [.MgSi] 

Venus  to  that  of  the  moon  ;    consequently, 


?•  =  0,0748013.^  .         Hence,      î —  ?«  =  0,0748013  .  ^^ 
1  «'■ 


[5493c] 


and,  by  substituting  the  values  of    n',  n"     [4077],  it  becomes  as  in  [5492']. 

t  (3050)     In  the  present  notation,     P     is  the   mass   of  the   planet  [5455],     »«'     that 

p 
of  the  sun  [4757"]  ;  hence     -,     of  the  present  notation,  is  the  same  as  m'  [4061  line  3],    t^^^^a] 


628  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

rir' 

-L  =.  0,0000015553  1 

a 

—  0,0000060012.cos.(i— m).»  2 

^^^^^^  4-  0,0000171431. cos.2.(i—m).v  3 

+  0,0000027072.cos.3.(î— m).w  4 

+  &c. 
The  function  [5490],  reduced  to  seconds,  becomes,* 

+  0%448818.sin.(i — m).v  1 

—  0',645333.sin.2.(i— m).v  •  2 

[Terms  of    ««+;] 

—  0',068705.sin.3.(i— wî).îJ  3 
&c. 

If  we  connect  this  with  the  preceding  expression  [5495],  toe  shall  have  for 
the  lunar  inequalities,  depending  on  the  direct  and  indirect  actions  of  Venus, 
upon  the  moon  ; 

+   1 ',026091. sin.(i—TO).tJ  1 


Indirect 
action  of 
Venus. 


[5496] 


Whole  ac- 
tio;! uf 
Vonua  on 


nl^-s.                                        —  0',40S414.sin.2.(t— m).z>  2 

[5197]  [Terms  of    nt-\-B]      ^ 

+  0%062758.sin.3.(i— m).«  3 
&c. 

We  must  increase  these   inequalities  in  the  ratio  of  1,0743    to  1    [4605]. 


[54946] 


and  by  putting     (^'=0,     it  becomes  as  in  [5493].     Substituting,    in   [5479],  the   values 
[5491—5493],  also  that  of    m     [5117],  it  becomes  nearly  as  in  [5494]. 

*  (3051)     Comparing  [5487,  5495],  we  get, 

P  P 

—      ^0)  ='0,0000015553  ;"  — .  iC''>  =  —  0,0000060012; 

m!  '  '  ^ 

^^  ^2)^0,0000171431,      &c. 
m' 

Substituting  these,  r,nd     m     [5117],  also     i—m     [5492'],  in  [5490],  we  get  the  terms  of 
[5496i]      ,.^_|_j  ^     arising  from  the  indirect  action  of  the  planet  Venus  on  the  moon,  as  in  [5496]. 


[5496a] 


VII.  iii.§22.] 


ACTION  OF  THE  PLANETS. 


629 


Relativel}'  to  Mars,  we  have  from  [4159,  4165], 


Hence  we  deduce,* 


a  =  0,65630030  ; 

(0) 


6,856336 


a 

(1) 


b^  =  5,727893 

2 

&'''  =  4,404530 


(3) 


b^  =  3,255964 

2 

&c. 


(0) 

b^  =  38,00346  ; 

2" 
(0) 

b^  =  36,20013 . 

2 


I        Action  of 
AlaiB. 


2 
3 
4 
6 


[5498] 


[5499] 


Observations  give     i  — m  =  — 0,0350306  ;t  therefore,  by  supposing,  as  in      ^^^qq-^ 
[4061  line  5], 


1 


m'         1846082  ' 


[5501] 


*  (3052)     Substituting  the  values  [5498],  in  [5492a],  we  get  [5499].  [5498o] 

t  (3053)     Changing     n'     into     ?i"'     in  [5493c],  we  get  the  value  of 


i—  OT=  0,0748013 


(«"'— n") 


[5500a] 


corresponding   to    Mars  ;   and,   by   using    the    values    [4077],   it  becomes  as  in  [5500]. 

Substituting  these,  and     -'    [5501],  in  [5481],  we  get  [5502].     The   expression  [5504], 

is  deduced  from  [5490,  5503],  in  the  same  way  as  [5496]  is  obtained   from  [5490,  5495], 
in  [5496«,5].     In  the  original  work,  the  coefficient  of  [5505 line 2],  is  erroneously  printed, 

1",201491  =0%3S9283,     instead  of    1",21 1491  =  0',392523  .  [5500c] 

VOL.  III.  158 


630  THEORY  OF  THE  MOON  J  [Méc.  Cél. 

the  function  [5481],  becomes, 
Direct  — 0%029177.sin.(i — m).v 

action  of 

"""•  —  0^01 1260.sin.2.(i— m).t; 

t5509]  _0^005584.sin.3.(^■— m).?;  [Terms  of    nt^,-] 

&c. 
We  have,  in  [4306  lines  8 — 11],  from  the  action  of  Mars, 

-  =  _  0,0000000478  I 

a 

+  0,0000G05487,cos.(«— m).«  2 

[5503]  ^  0,0000080620.cos.2.(i— m).t)  g 

—  0,0000006475.cos.3.(z— m).ij  4 
&c. 

The  formula  [5490],  reduced  to  seconds,  becomes, 

+  0',054760.sin.(î— m).iJ  1 

action  of 

M»-  +  0',403783.sin.2.(i— m).z;  2 

r.^,  .,  [Terms  of    nl-\-t] 

[^5"4]  _  o\021753.sin.3.(z— m).t>  3 

&.C. 

If  we  connect  together  the  terms  in  [5502,5504],  we  shall  obtain  the  lunar 
inequalities  depending  on  the  direct  and  indirect  actions  of  Mars  upon  the 
Moon  ; 


Complete 
action  of 
Mars  on 
n/+£. 


+  0%025583.sin.(î— m).^)  1 

+  0%392523.sin.2.(î— m).t;  2 

[5505]  _  0%027337.sin.3.(/-m)..  [Terms  of  n.+.]  3 

&c. 
We  must  decrease  these  inequalities,  in  the  ratio  of    0,725     tp     1      [4608]. 
Relatively  to  Jupiter,  we  have,  as  in  [4167,4173], 


VII.  iii.  >^  22.] 


ACTION  OF  THE  PLANETS. 


631 


a  =  0,19226461  ; 


(U) 


b^  =  2,176460; 


3. 
2 

.(1) 


6    =  0,619063; 


(2) 


6,  =  0,148198; 


&^'=  0,032439 

2 

&c. 


Action  of 
Jupiter. 


2 
3 

4. 
5 


[5506] 


Hence  we  deduce,  from  [5492a], 


(0) 

h^  =  2,51906; 

2 

hl=  1,13310. 

2 


I 

2 


We  have,  by  observation,    i  —  m  =  —  0,0684952  ;*  therefore,  by  supposing, 
as  in  [4061  line  6], 


p          1 

m'  ~  1067,09  ' 

the  function  [5481]  becomes, 

—  0',070391.sin.(î— m).«; 

1 

—  0%008547.sin.2.(i— m).« 

2 

—  0%001275.sin.3.(i— m).t> 

[Terms  of    n«+;] 

3 

&c. 

[.5,507] 


[5.508] 


[5509] 


Direct 
action  of 
Jupiter- 

[5510] 


*  (3054)     Clianging     n     into     n'',     in  [5493c],  we  get  the  value  of 

i-.,  =  0,0748013. ^:^"1,  [5508a] 

corresponding  to  Jupiter;   and,  by  using   the   values  [4077],  it   becomes  as    in    [5508]. 

p 
Substituting   this  and     -,     [5509],  in  [5481],  we  get  [5510].     The  expression  [5512]  is 

deduced  from  [5490,  5511],  in  the  same  manner  as  [5504]  is  found,  in  the  last  note. 


632  THEORY  OF  THE  MOON  ;  [Méc.  CéJ. 

We  have,  from  [4306, lines  13 — 16],  by  means  of  Jupiter's  action, 

-  =  —  0,0000011581  1 

a' 


[5511] 


Indirect 
action  of 
Jupiter. 


[5512] 


+  0,0000159384.cos.(î— m).!)  2 

—  0,0000090986.cos.2.(î— m).?;  3 

—  0,0000006550.cos.3.(i— m).i'  4 
&c. 

Tde  formula  [5490],  reduced  to  seconds,  becomes, 

+  0',816336.sin.(i— ?«)-«^  1 

—  0%236377.sin.2.(i— m).«  2 

—  0%0n625.sm.3.(i—m).V  [Terms  of    nt-\-s]  ^ 

&c. 

If  we  connect  it  with  the  preceding  [551 0],  we  obtain  for  the  lunar  inequalities 
depending  on  the  direct  and  indirect  actions  of  Jupiter  upon  the  moon. 

Whole  +  0%745945.sin.(z — m).v  \ 

action  of 

^''nt^r  —  0^244924.sin.2.(i— m).i'  2 

—  0',012900.sin.3.(î— m).i;  [Terms  of  «<+£]  3 
&c. 


[5513] 


[5513']  If  we  take,  with  a  contrary  sign*an  the  inequalities  resulting  from  the  actions 
of  the  planets  upon  the  moon,  [5497,  5505,  5513],  we  shall  obtain  the 
inequalities  ■produced  by  this  action,  in  the  expression  of   the  moon's  true 

[5514]  longitude;  we  may,  therefore,  reduce  them  to  tables,  observing,  that  {i—m).v 
may  be  supposed  equal  to  the  mean  longitude  of  the  planet,  minus  that  of 
the  earth.  It  would  be  useful  to  introduce  these  inequalities  into  the  lunar 
tables,  considering  the  precision  to  which  these  tables  have  been  carried. 


*  (3055)     The  inequalities  of  the  expression  of    nt-\-s     [5095],  arising  from  the  actions 
[5515i]    ^j.  ^j^g  planets,  are  given  in  [5497,  5505,  5513]  ;  and  to  obtain  the  corresponding  terms  of 
«     [5095],  we  must  ev'dently  change  their  signs. 


VII.iii.§22.]  ACTION  OF  THE  PLANETS.  ^^^ 

PA'.")  1      /dQ\  .  .        , 

The  term      ^3,     of   the    expression   of    — -.(^-^j,     gives,  in  the      [5515] 
equation  [4961],  the  term,* 

J.P«^  J""  e    .  COS.(CV îî).  (Term  of  4%1]  [5516] 

Hence  it  is  evident,  that  the  value  of    c     is  decreased  by  the  action  of  an 
inferior  planet,  by  the  quantity,  f 

P  /o' 

f  .  —  .  m~.  0  3    ;  •  (Decrement  of  c]  [5517] 


2 


and,  by  the  action  of  a  superior  planet,  by  the  quantity, 


p  ^  (0) 

3.  .  —  _  in~'  Oi?.h      •  [Decrement  of  c]  [551S] 

8  ,y^l  3 


* 


1    /dq\ 
(3056)     The  equation  [4754,  or  4961],  contains  the  term     — p'Vrfil"/'     which 


is  developed  in  [5470],  and  contains  the  term    _— — ^.        Substituting    h^=a     [49377i], 

^'''•"  [5516a] 

and      M     [5393],    which  gives     —  =  «^.{1 — 3e.cos.(CT — w)},     nearly;    we  obtain  the 


w 


term  [5516],  depending  on    e. 

t  (3057)     Neglecting     e^     c'^,     and  also,  for  brevity,  the  symbol     •«,     we  have,  as 

in  [5396a],     — j^     for  the  coefficient  of    -.cos.ct,     in  [4961]  ;  hence  it  is  evident,  that 

the  quantity  [5516]  increases  p,  by  the  term  Sp=:^P.a'.A^''\  The  corresponding 
increment  of  the  motion  of  the  perigee  is  ^Sp.v=yP.a^.A'-''Kv  [5396^].  Substituting 
the  value  of    a^     [5473«],  it  becomes, 

p 

■|.— 7.m2.«'3.^(0).^_  [55166] 

Now,  the  motion  of  the  perigee  is  represented  by  (1 — c).v  [4817]  ;  hence  it  is  evident, 
that  the  preceding  expression  decreases  the  value  of    c    by  the  quantity, 

4-.-  .m^.a'^.A^''\  [5516c] 

"     m 


If  we  substitute  the  value     a'\A^<'-^  =  b^      [5478rf],    corresponding  to  an  inferior  planet, 

it  becomes  as  in  [5517]  ;  and,  if  we  use  the  value  «'3.^(°'=  <v>.b^  [5480&],  corresponding    [5516rf] 
to  a  superior  planet,  the  decrement  of    c    becomes  as  in  [5518]. 
VOL.  III.  159 


634  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[5519]     Likewise,  the  term     --^     [4865']     gives,   in    the  equation    [4961],    the 


quantity, 

9 

"2A2       '""a' 


[5520]  — ^  .«=.  —  .  e.  COS.  (cîJ—n)  ; 


5r' 
[5521]     —    representing  the  constant  part  of  the  perturbations  of  the  radius  vector 

[5521']     of  the  earth's  orbit,  given  in  [4306].     Hence,  the  value  of   c    is  increased 
by  this  means,  by  the  quantity,! 

9  m^      or' 

.15522]  — —    .    — r  .  [Increment  of  cj 


i5530ol        *  (3058)     The  variation  of  the  term  [5519]  is  given  in  [5486c],  namely,     ^j^-^  ■  ^  : 
and,  by  substituting, 

•5"'                 ^'■'        rr^ocn       w  I  3m'.u'3   6r 

[55206]  —  = [54866],     It  becomes     —  .-• 

If  we  use  the  value  of    u'^     [5516a],  it  will  produce  tlie  term, 

r5520c]  -— -—.a^  —  .e.cos.  (ct)— «),     dependmg  on  e. 

hi  the  original  worli  it  is  erroneously  printed, 

9»i'.k'3      6r'  ,  , 

,j..„,, ,,  •  .  — r  .e  •  COS.  (cv — ■ss)  ; 

[5530rf]  2A3.M3       a'  ^  •" 

the  sign  being  wrong,  and     «^     changed  into     ir^. 

t   (3059)     Substituting     «'=«'-',     h~  —  a     [4937ft],  and   then     --;y  =m2  [-5475j^ 


a' 
This  produces,  in    j)     [5396a],  the  term. 


in  [5520],  it  becomes  g      a   ^     £  (rv-.-!.-) 

[5522a]  ^  ^^«-a'     •  ^  •  C0=,.  (cy— raj. 


[55226]  ^.P ^'"^'"^   ' 

and,  in  the  motion  of  the  perigee     i&p.v     [5396(Z],  the  term, 


9 


fir' 
m~  .  ■—  .  V  . 


[5522c]  4  '"    •  a' 

Now,  the  motion  of  the  perigee  being     {l—c).v     [4817],  it  is  evident,  that  this  produces 
|5522rf]    an  increment  in  the  value  of    c,     which   is  represented  by  the  function  [5522].      In  the 

original  work,  the  word  increased  [5521'],  is  printed  decreased. 


VII. in.  ^22.]  ACTION  OF  THE  PLANETS.  635 

It  is  easy  to  prove,  that  all  these  quantities  are  insensible.*  [5522'] 

ffe  shall  now  consider  the  perturbations  of  the  moon'' s  motions  in  latitude. 
The  sum  of  the  terms, 

s  /^\  (l  +  .O       A!Q\  ,Te™s  of 47551  [5523] 


.       [Terras  of  4755] 

K^.U     \duj  li^.U^  \(fs  J  Perturba- 

tions 

which  make  a  part  of  the  equation   [4755],  acquires,  by  the  action  ot  the    [noon^s^ 
planet    P,    the  quantity, t  action 

planets. 

3P.S       ,  3P.Rr'.S.cos.(v—v')—3P.R\S.cos.(v—U) 

— 4- ^^ ^^ ■     '  [Terms  of  4755]  [55241 

This  function  contains,  relatively  to  an  inferior  planet,  the  term,t 


*  (3060)  That  these  quantities  are  insensible,  is  evident  by  computing  any  one  of  the 
terms;  for  example,  that  in  [5517],  corresponding  to  Venus.  Substituting,  in  this,  the 
values  of 

P  (0) 

;7=3Wt^7     [5493];        m^  =  0,0055     [5117./]  ;        b,  =  10,     nearly  [5491]  ;      ^ggag^j 

we  get, 

I ,  £r  .  m^  .  C  =  0,00000006  ;  [55236] 

which  is  insensible,  in  comparison  with  the  whole  coefficient  of  the  motion  of  the  perigee 

c— 1  =  0,00815199     [5117  line  2].  [5523c] 

t  (3061)  Taking  the  partial  differentials  of  Q  [5468],  relative  to  u.  s,  we  get, 
by  neglecting  terms  of  the  order    s^, 


s 


\du)~       2u3/3      ^^•«•—  yM3.y5  ;     [5524a] 

fdq^_       2P.S  RS.{R.cos.(v-U)-,-'.cos.{v-v')\ 

1  (!+««)  1 

Multiplying    [5524a],  by     —  ^,     and  [5.524i],  by    — -f~,     or  simply,  by    ——. 

and  adding  the  products,  we  get  the  value  of  the  function  [5523],  as  in  [5524],  nearly  ;      [5524c] 
neglecting  the  terms  depending  on  the  angles     2« — 2t7,     2« — 2«',     2v — V — v';    because 
they  do  not  produce,  by  the  integrations,  any  term  of    s,    having  the  small  divisor    g — 1  ;     [5524rf] 
which  the  other  terms  [5527,  5528]  acquire,  as  will  be  seen  in  the  following  note. 

•iP  s 

X  (3062)     We  shall  notice  the  effect  of  the  first  term  of  [5524]    -      '         in  [5534«], 


636  THEORY  OF  THE  MOON;  [Méc.  Cél. 

(,3        /  (0)  (1)   f 

[5525]  f-P-^-'-Tg'S^-'^S  "s      (^  .Sin.(t; è)  ;  ITorms  of  4755] 

'^  t  '2  '2       ) 

[5526]     X    being  the  inclination  of  the  orbit  of  the  planet  P  to  the  ecliptic,  and  <'  the 

and  shall  consider  the  rest  of  this  function  in  the  present  note.     If  we  divide  the  equation 

p 

[5525a]    [5469],  by     — -^,     and  substitute  [5473],   we    shall    obtain,  successively,  the  values   of 

f~^  [5525è,c]  ;  and,  by  using  the  same  notation  for   f"^,    we  get  its  value  [5525fZ]  ; 

[55256]  ~^^A^o)j^^(iicQs.{U—v')+A^-\cos.2.(U—v')-\-hc. 

[5525c]  =  4-,  •  S  i*r+  ^1"- t^os. ( U—v')-\-li'l  cos.2.{U—v')+  &c.  \  ; 

1  1  f  to)  (1)  (2)  ■) 

[5525rf]  TT  =-5-     IK  +l>,.cos.{U-v')+h^  .cos.2.(£7-^')+&c.     . 

J  ^         a  -^    i       -2         2  g-  ) 

The  first  of  these  developments  is  used   in  [55346];  the  second  in   this  note   [5525Â]. 
[5525e]     Now,  as    X    is  very  small  [5526, 4082],  we  shall  have,  very  nearly,     &'  =  X.sin.([^ — è) 
[5526,5463,679]  ;  hence  we  get, 

[5525/]  S.cos.(y— ti')  —  iX.sin.(L^— î^'+u — â)+JX.sin.(r-j-î)'— r — è)  ; 

|-5505g.]  S.cos.{v—U):^\'k.s\x\.{v—è)-\-^\.sm.{2U—v—è). 

We  shall  now  multiply  these  two  last  expressions  by  the  value  of  f~^  [5525(7],  and 
reduce  the  product  by  formula  [18]  Int.  ;  neglecting  the  terms  in  which  the  coefficient  of 
the  angle  v  differs  considerably  from  unity  ;  because  they  are  not  much  increased  by 
integration;  whilst  the  terms  depending  on  sin.(y — é),  are  considerably  augmented  by 
[5525i]  the  divisor  of  the  order  g — 1,  as  in  [53476  or  5527,  5528]  ;  hence  we  get,  by  making 
the  usual  reductions  ; 

[5525i-]  —.S.cos.^v—v)  =j^^.b^.s\n.{v—è)+'kc.; 

1  X       ^^^ 

[5525/]  -^..S.cos.(._l7)=-.6^.sin.(^-^)+&c. 

Substituting  [5525A-,  l\  in  the  two  last  terms  of  [5524],  they  produce  the.  folloiving  term 
of  [4755]  ; 

3P.P./..S.cos.(.-.0-3P.fi^S.cos.(.-f7)_     3FR  j^,  ."L/?.r;.x.sin.(,,-.V 
[5525m]        h^.%l\p  Ah^.u\a">i         J  ^S  ^  ' 

Substituting,    in    this    second    member,   the    approximate    values     h^  ^  a,       u^crK 
[5525)t]    r'=a'    [5470«,  &.C.]  ;  and,  for  an  inferior  planet,     R  =  a.a',     nearly  [5462,  5477,  &c.], 
we  get  the  expression  [5525]. 


VII.iii.4.'2-2.]  ACTION  OF  THE  PLANETS.  637 

lomitudeof  its  ascending  node.     This  produces  in    s,  for  an  inferior  planet,     [5526'] 
the  term,* 

*  (3063)     If  we  put,  for  brevity, 

in  the  second  member  of  [55-25ot],  it  becomes    H'.ûn.{v  —  è).      Tliis  represents   a    term     [55275] 
of  the  equation  [4755],  or  of  the  similar  equations  [5347/,  m]  ;  and  may  be  integrated  as 
in   [5347/ — «'].       If   we   su])pose    the  term   of    Ss,     corresponding  to  [5527i],  to  be 
represented  by  &'s^R".sm.{v — è),   which  is  similar  to  [5348]    the  equation  corresponding     [5527c] 
to  [5347/h],  will  become, 

0  =^+.-f  fl-'.sin.(t»-0)  +  fe-2-l).//".  sin.(«-â).  [5527^] 

Substituting,  in  this,  the  assumed  vakie   of    s,     or     <h,     [5527c],  we  find,   that   the  two 

first  terms  mutually  destroy  each  other.     Dividing  the  rest  by    sin.(M — è),    we  get  the      [5527e] 

following  equation,  which  is  similar  to  that  in  [5347»]  ; 

0=fl'+(o-2-l).f/".  [5527/] 

Dividingby    g''—\={g-^V).{g—\)=2.{g—\),    nearly  [5-35 la],  we  get  H"=——^-.     [5527^-] 
Substituting  this  in    as    [5527c],  and  then  resuming  the  value  of    li'     [5527 a],  we  get, 

^'  =  8.{g-l).h^n\a'n^ ■  \-  '''-^l  S •^•^'"■(^-^) •  [5527M 

Substituting  the  values  [5525ra],  corresponding  to  an  inferior  planet,  we  get  [5527«]  ;  and, 
by  using  the  value  of   a^    [5473a],  it  becomes  as  in  [5527A;]  ; 

3Pa         «3      ,-  (0)         (1)  ^ 


m' 


(0)         (I)  ) 
a.ôj   — ftj     >  .X.sin.(i) — (3).  [.5527A;] 

'2  2"     ) 


This  agrees  with  [5527]  ;  observing,  that  jve  have  corrected  this  formula,  for  a  mistake  in 

the  original  work,  where  it  is  printed  ivith  the  prefix  of  a  negative  sign.  [.5527i] 

In  making  the  calculation  for  «  s!<periorp/aMe^,  we  must  change  the  factor     -7-,     in  the 
second  member  of  [5525f/],  into     -— ;  and  the  same  change  must  be  made  in  [5527a,  A]  ; 

XL-'  [5527771] 

by  which  means,  this  last  formula  becomes,  for  a  superior  planet, 
VOL.  III.  160 


638  THEORY  OF  THE  MOON  ;  [Méc.Cél. 

Terms  of 

6s,  ,  P  (        (0)         (')  ) 

[5527]  l--,-^»»'-^^-^^— &A    \ 

6  6'  =    ^^ — ^.X.sin.(î) â)    ;  [inferior  plaoetj 


arising 
from  the 
action  of 
an  inferior 


O 


planet;       aïià,  foT  o  supcnor  planet,  this  inequality  becomes, 


p                     (       (0)                (1)    ) 
[5528]  6s    =    ^— Y ^-^.X.Sin.(» è).  [Superior  planet] 


and,  from 
tiiat  of  a 


superior,  S!" 1 

planet.  "^ 


Reducing  these  inequalities  to  numbers,  by  using  the  masses  of  Venus, 
Mars  and  Jupiter  [4605, 4608,  4065],  we  get,  for  Venus,* 

[5529]  ^s    ^    —  0^276468.sin.(î;— «')   ;  [Action  of  VennsJ 


[5527o] 


Now,  substituting  as  in  [5525n],     h^  =  a,     u  =  a  ^,     r'=a,     and  then,     R^-, 
get  [5527J3]  ;  and,  Idj  using     «^     [5473«],  it  becomes  as  in  [5521q]  ; 


we 


3Pa3        «3      (     (»)  (1) 


p 


This  agrees  with  [5528]  ;  the  expression  being  corrected  as  in  [5527/], /or  the  mistake  of 
^  ^^  prefixing  the  negative  sign.  The  terms  we  have  here  computed  [5527A,  «7],  have  the 
small  divisor  g — 1,  of  the  order  m-  [4828e]  ;  and,  even  with  this  divisor,  they  amount 
only  to  a  fraction  of  a  second,  as  appears  in  [5529 — 5531]  ;  hence  it  is  manifest,  that  the 
terms  of  this  kind,  which  have  large  divisors,  must  be  wholly  insensible. 


[5527«] 


P  1 

*  (30G4)  Substituting,  in  [5527], the  values  of    ^  =  ^^     [4605],    a    [4126],  also 

("1  (0 

[5529a]  /j[^  h^  ,  deduced  from  [5492],  g,m  [5117],  \=<s?'  [4082],  it  becomes,  as  in  [5529]. 
a"  5" 
In  like  manner  we  obtain  from,  [5528],  the  expressions  [5530,553!]  ;  using  the  mass  of 
Mars  [4608],  and  that  of  Jupiter  [4065]  ;  also  the  other  elements  as  in  [4159 — 4173,4082]  ; 
m ,  g ,  being  as  before.  We  have  corrected  the  signs  of  the  expressions  [5529,  5530, 5531], 
for  the  error  [5527?,)-],  ivhich  is  foundinthe  original  ivork;  the  numeral  coefficients  given 
by  the  author  being. 


[55296] 
[5529c] 


VII.iii.§22.]  ACTION  OF  THE  PLANETS.  639 

and,  for  Mars, 

^5   =    +0',005497.sin.(l'— r);  [Action  of  Ma»J  [5530] 

also,  for  Jupiter, 

o's  = +0%037925.sin.(?;— ^")  ;  f Acion  of  jupHer,  [5531] 

è',  ê'",  ê'",     being   the   longitudes  of  the   ascending   nodes   of  the  orbits   of     [5532] 
Venus,  Mars,  and  Jupiter. 

Finally,  it  is  evident,  that  the  value  of    g,  is  increased  by  the  action  of  the 
planet     P  ,     by  the  quantity, 

P  (0) 

I .  — .  nî^.  63  ,     relative  to  an  inferior  planet  ;  [5533] 

WÎ  "2  Increment 


and,  by  the  quantity. 


o(     ff,     by 
the  direct 
action 
of  the 
planets- 


P  (0) 

I .  —  .  m^.  0-^.  63  ,     relative  to  a  superior  planet*  [5534] 


m 


+  0",85329C  =  +0^276468  ;    — 0",016966  =  —  0%005497  ; 
—  0",117051  =— 0',037925. 


[5529d] 


2P.S 

*  (3065)     If  we  substitute,  in  the  first  term  of  [5524],  ^'  -  ,    which  was  neglected     rrco^  -i 

in  [5525a],the  value  of     —     [5525J],  and  retain  only  the   part  which   is   independent  of 

U — v',     we  obtain  the  expression  '^   .  ^^'°\       Substituting    the    values      h^  =  a  ,     [55346] 

«  =  a~%     and     a^    [5473o],  it  becomes  successively, 

This  term  of  [4755],  increases  the  value  of    p"     [5397^,  /  ],  by  the  quantity, 

6p"  =  I .  -  .  m^.  a'3.  ^(oi ,  [5534rf] 

m 

and  the  corresponding  increment  of  the  motion  of  the  node  [5397/],  is, 

h¥'-^=i-~-m'.a'\A^o\v.  [5534,^ 

Now,  the  motion  of  the  node  is  represented  by     (g—  \).v     [4817]  ;  hence  the  increment 
of    g     is  represented  by, 


64.0  THEORY  OF  THE  MOON  ;  t^^c.  Cil. 

rpi  3m'.u'^,s 

Ine  term  ^  —  ,     which  forms  a  part  of  the  equation  [4755],  and  is 

t^^^^^      developed  in  [5021],  decreases  the  value  of  g,    by  the  quantity,     ^  .  ^  ;* 

Decrement  ^  ** 

—7     being  the  constant  part  of  the  perturbations  of  the  radius  vector  of  the 


the  mdi 

reel  action 

or  the  « 

planets, 


[5536] 


earth's  orbit.  Hence,  the  value  of  g  is  decreased  by  the  action  of  the 
planets,  by  the  same  quantity  that  c  [5522]  is  increased  by  the  same  action. 
But  these  quantities  are  insensible  [5535/"]. 

The  direct  action  of  the  planet     P     upon   the  moon,  introduces   in  the 
equation  [4961],  a  quantity  of  the  form,t 


[5534/]  *         ^     m 

[553%]     For  an  inferior  planet,  we  have      a'^.A'^°^=^l>3      [5478f7]  ;    substituting   this  in  [r35o4/] 

fO) 

[55347t]      we  get     &g     [5533].     For  a  superior   planet    a'^.  A'"''  =^  a?.b^      [54806]  ;    hence     Sg 

1 

[5534yj,  becomes  as  in  [5534]. 

*   (3066)     Tlie  variation  of  the  term     —pcr^—r  >     taken    relatively   to     u',      becomes 
[5535a]  ^  ^  S/Ak"  ^ 

.        as  in  the  first  or  second  member  of  [5535c].     Substituting      —  = ;      [55206],    it 

becomes  as  in  its  third  member  ;  and,  by  successive  substitutions,  using  the  values  [55346], 
we  finally  obtain  [5535cZ]  ; 
9m'.u'-U.s 


[5535c] 
[5535rf] 


2/i2.  ; 


9m'.  iP.  s     Su' 

9  m' 

m'''.  5 

&r' 

9  m' 

«3 

&r' 

.  s 

2h^.iâ    '   u'  ~ 

2 

F.M^ 

a' 

2 

■  a'3' 

a' 

9m^      Sr' 

2     ■    a'   ■  ^  ■ 

Now,  proceeding  as  in  [5534c,  Sic]  we  find,  that  the  expression  [55o5<Z],  produces  in     p" 

[5535e]      the  term      (5p"  =  —  f  m^.  —  ;     and  tiierefore  in     g     the  increment,      Sg  ^  —  |  m^.  —, 

as  in  [5535]  ;  being  the  same  as  that  of  c  [5522],  except  in  its  sign.  The  quantities 
thus  computed,  in  [5533,  5534,5535],  are  of  nearly  the  same  order  as  that  in  [5522],  and 
must  be  insensible,  as  in  [5522']. 

f  (3067)     As  an  example  of  the  manner  in  which  terms  of  the    form  [5537],  or  such 
as  are  free  from  the  sines  and  cosines  of  the  periodical  angles,  are  introduced   into  [4961], 
[5537a]     by  means  of  the  function      ^  ,     we  may  mention,  those  which  arise  from   the  substitution 
of    /    [5466],  in     Q    [5467].     For,  in  [669  line  1],  we  have,  relative  to  the  earth. 


VIl.iii.§22.]                        ACTION  OF  THE  PLANETS.  641 

M.  ^  .  7n^e'^+3î.  -, .  m\e'e"-{-M".  -,  .  m^e"^+&c.  ;  [5537] 

m  m  m 

e"    beins;  the  ratio  of  the  excentricity  to  the  semi-major  axis,  in  the  orbit  of 

P.     Hence,  there  arises  in  the  moon's  mean  longitude,   a  secular  equation  j",^^'","^^,^ 

analoîTOUS  to  that  we  have  found  in  [5095^?],  sccùiar 

equation. 


m"-.  /  (e'-^—  E'^).dv.  [5538] 


This  last   expression    arises    from    the    development   of  the    term  3 

[4866  line  l,5083,&c.]  ;  and  it  is  incomparably  superior  to  the  former,  on 

p 

account  of  the  small    factor     — ,      connected    with    the    first    expression. 

m  *■ 

Thus,  the  indirect  action  of  the  planet  P   itpon  the  moon,  transmitted  by  means     [5539] 
of  the  sun,  is,  as  it  regards  this  inequality,  much  more  important  than  the  direct 
action,  ivhich  may  be  neglected,  ivithout  any  sensible  error. 


r'  =  a'.H  +i(i'^—  e'.  cos.  z)'4-&c. }  ;  [5527b] 

and  for  the  attracting  planet  P  , 

R  =  R".\  1  +ie"^-  e".cos.  U+hc.];  ^5537,^ 

R"     being  its  mean  distance.     From  these  values,  we  easily  perceive,  that     r'^     contains 
a  term  depending  upon     e'^;     R^     a  term,  depending  on     e"^;     Rr'     a  term,  depending 
on     e'e".cos.(U — v')  ;      therefore,     Rr'.cos.^U — v')     contains  a  term  depending  on     [5537^] 
e'e".     Substituting  these  in  [5466],  we   find,    that    /    contains  such    terms,   free    from 
periodical  angles,  and  depending  on     e'^,     e'e",     e"^  ;     which  are,  by  this  means,  introduced     [55376] 
into     Q     [5467],  and  finally  into  [4961].     If  we  proceed  with  the  function  [55.37],  by  the 
method  which  is  used  in  [5083 — .5089],  it  will  produce  terms  of  the  form  [5087],  or  rather    rKK'i^fi 
like  [5095(7, or  5538]  ;  but  they  will  be  much  less  than  those  in  [5538],  by   reason   of  the 

p 
small    factor     —, .  ?n^,      which  attaches,  as  in  [5476],  to  the  terms  depending  on  the  direct 

™  [5537ff] 

action  of  the  planet   P. 


VOL.  III.  161 


642  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


CHAPTER    IV. 


COMPARISON  OF  THE  PRECEDING  THEORY  WITH  OBSERVATION. 


23.  In  the  first  place,  we  shall  consider  the  mean  motions  of  the  moon, 
of  the  perigee,  and  of  the  nodes.  The  expression  of  the  moon's  mean 
longitude,  in  a  function  of  its  true  longitude,  contains,  in  [5095],  the 
secular  inequality, 

[5540]  I  m\f(e"-E").dv. 

Hence,   the   expression  of  the  true  longitude,    in    a  function  of  the  mean 


Secular 


of  u,T'"^    longitude,  contains  the  secular  inequality 

longitude  ; 

[5541]  iv  =  —pn^.f(e'^—E"').ndt. 

If  we  represent  the  number  of  Julian  years  elapsed  since  1750,  bij     t,     we 
shall  have,  as  in  [4611], 

[5542]  2e'  =2E'—t.0%nil93—t^  0  ,0000068194. 

reduced  to    Thercforc,  the  inequality  [5541]  is  represented  by,t 

3eC0Q(l9. 

[5543]  6t,=  10%181621.î^+0%01853844.i=^;  ['TtgS'™] 


*  (3068)     From  [50966]  we  obtain, 
[5541a]  v  =  7it  +  s— |mS./(e'2— E'2)  .rfy— 2  C.sin.  (lî^+p) . 

[55415]    In  the  secular  part  of  this  expression     —^m^.f{e'''—E"').fh,     we    may    substitute     ndt 
for     dv,     and  it  will  become  as  in  [5541]. 

t  (3069)     If  we  put     2a,     2b,     for  the  coefficients  of    t,     t^     [5542],  divided  by 
[5543a]    jj^g  j.^jj^jg  jjj  seconds     206265%     to  reduce  them  to  parts  of  unity,  we  shall  have, 


Vll.iv.§23.]     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION.  643 

i  being  the  number  of  centuries  elapsed  since  the  epoch  of  1750.  This  [5543] 
secular  equation  was  found  by  observation,  before  I  discovered  the  cause 
of  it  by  the  theory  of  gravity.  It  is  ascertained,  by  the  comparison  of  a 
great  number  of  eclipses,  Avhich  were  observed  by  the  Chaldeans,  Greeks, 
and  Arabs,  that  the  moon^s  mean  motion  has  increased,  from  the  most  remote 
period  to  the  present  day  ;  and  the  observed  acceleration  is  very  nearly 
conformable  to  the  preceding  theory.  This  secular  equation  is  placed  beyond 
doubt,  by  Mr.  Bouvard,  by  a  profound  discussion  of  the  ancient  eclipses, 
which  were  known  to  astronomers  ;  and  also  of  those  he  has  obtained  from 
an  Arabian  manuscript  of  Ibn  Junis. 


[5544] 


[5544'] 


We  have  seen,  in  [5231],  that  the  sidéral  motion  of  the  moon's  perigee, 
deduced  from  the  preceding  theory,  differs  from  its  true  value,  but  by  a  four 
hundred  and  forty-fifth  part.*  According  to  the  theory,  this  motion  is 
subjected  to  a  secular  equation  equal  to    — 3,00052.A;  ;     k  being  that  of  the      [5545] 


0 171793 
«  =  ^^aôëacJ  =  0,000000416438  ; 

,  0,0000068194 

*  =     2X206265  =  0,0000000000165307. 


[55436] 


We  also  have  £'=0,01681.395  [4080  line  .3],  corresponding  to  e'  [5117]  ;  hence, 
[5542]  gives,  by  neglecting  terms  of  the  order    t^, 

e'  =  E'—at—ht"~;     and,     c'^  =  E'^-2E'.{at-i-bfi)-\-a^f.  [5543^^ 

Substituting  this  expression  of    e'^,     in  the    secular  equation  [5541],   it  becomes  as  in 
[5543/]  ;  whose  integral  is  in  [5543o-]  ;  and,  by  putting      t==z]OO.i     [5541',  5543'],  we     [5543e] 
get  [5543/-]  ; 

6v  =  §m^n  .f{2E'.  atdt+{2E'h—cv').tHl\  [5M2,f] 

=  imH.\E'.  at^-^{%E' b-W)A  ^5543^5 

=  J.IOO^  nv'n  .£'a.ia+|.1003.7?!2n.(§E'  h—ia^).i^.  \^Uih^ 

This  last  expression  is  easily  reduced  to  the  form  [5543],  by  the  substitution  of  the  values 
of  a,  b.  E'  [.55436,  c],  also  m  [5117];  and,  for  n,  the  motion  of  the  moon  in 
a  Julian  year,  which  is  taken  for  the  unit  of  time  in  [5541'],  making 

m«=129577',349     [4077  line 3, 4835].  [5543,-] 


(3070)     This    is    erroneously   quoted   in  the    original  work,  as  a  five  hundred  and 

tbnnrf.  [5544a] 


sixtieth  part 


644  THEORY  OF  THE  MOON  ;  [Mcc.  Cél. 

moon's  mean  motion  [5232,  5541]  ;  so  that  the  secular  equation  of  the 
[5546]  anomaly  [5238]  is  4,00052. A;,  or  very  nearly  four  times  that  of  the  mean 
motion.  The  preceding  equation  was  discovered  by  me,  by  means  of  the 
theory  of  gravity  ;  and,  I  have  found,  from  the  theory,  that  the  motion  of  the 
moon^s  perigee  decreases  from  age  to  age  ;  and,  that  it  is  now  less,  by  about 
The  mo-    fifteen  centesimal  minutes  in  a  century,  than  in   the  time  of  Hipparchiis* 

tion  of  the  •  i  /»       i  i 

moons       This  result  of  the  theory  has  been  confirmed  by  the  discussion  of  the  ancient 
ecieas.ng.  ^^j  ^j^^  modem  observations. 

We  have  seen,  in  [5233],  that  the  sidéral  motion  of  the  nodes  of  the  lunar 
^  J  orbit,  upon  the  apparent  ecliptic,  deduced  from  the  preceding  analysis,  differs 
«tuauon  from  its  true  value  only  by  a  three  hundred  and  fiftieth  part.  The  secular 
node.  equation  of  the  longitude  of  the  node  is,  by  the  same  article,  equal  to 
[5549]     o,735452.A;     [5234,  5541].     This  is  also  confirmed  by  the  ancient  eclipses. 

24.      We  shall  now  consider  the  periodical  inequalities  of  the  moon''s  motion 

^       ■'     in  longitude.     In  order  to  compare  with  observation,  the  preceding  results 

inequai'i-"'   of  thc  theory,  we  shall  consider,  as  the  result  of  observation,  the  coefficients 

moon.        of   the  last  lunar  tables  of  Mason,   and  those   of  the  new  tables  of  Burg. 

The  coefBcients  of  Mason's  tables  have  been  determined  by  the  comparison 

of  a  very  great  number  of  Bradley's  observations  ;  and,  those  of  Burg,  by 

[5550]     means    of    more  than   three  thousand  observations  of   Maskelyne.     These 

tables   have    been    arranged  in  a    manner,    which  is  quite  convenient  for 

calculation  ;  so  as  to  diminish  the  number  of  the  arguments,   making  them 

[5550]    depend,  the  one  upon  the  other.     The  following  is  the  process  for  determining, 

by  Mason's  tables,  the  equations  of  the  moon's  true  longitude.    This  method 

I  have  developed,   in  a  series  of  sines   of  angles,   increasing  in  proportion 

to    V . 


*  (3071)     If  we  put   successively,  in  [5543],    {  =  — 20,     i  =  — 19,     we  shall  find, 

that  the  difference  of  the  two  results  is     6""  16';     which  represents  nearly  the  acceleration 

[5547o]    p£  jjjg  moon's  motion,  in  a  century,  since  the  time  corresponding  to  the  mean  of  these  two 

values    of   i,    or  1950    years  before  the   epoch   of  1750,    which    is    about   the    time  of 

Hipparchus.      Multiplying  the  preceding  expression   by     — 3,00052     [5545],    we  get 
[55476] 

nearly     19"     for  the  secular  decrement  of  the  motion  of  the  perigee  j  instead  of     15', 

given  by  the  author  in   [5547]. 


Coefficionls 

Coefficients 

of  lîurg'a 

of  Mason's 

Tables. 

Tables. 

VII.iv.§24.]    COMPARISON  OF  THE  THEORY  WITH  OBSERVATION.  645 

We  must  first  compute  the  following  terms,   iu  which  the  anomalies  are     [5550"] 
counted  from  the  perigee  ; 

Tables 
of  Mason 
und  Bur^. 

—  671',8.... —  66S'',6.sin.(0's  mean  anom.)  1 

—  6%0.... —  8°",9.sin.(2.@'s  mean  anom.)  2 
-j-  53',9. ...-}-  55%9.sin.(2.3>'s  mean  long. — 2.@  true  long.-{-@  mean  anom.)  3 
-j-     76',5....-|-     75*,3.sin.(2.  3>mean  long. — 2. @  true  long. — (2)  mean  anom.)  4 

—  57*,8.... —    57',8.sin.(2.  Jmean  long. — 2.0  true  long. -|- 3)  mean  anom.)  5 

-[-4829*,5....-(-4S28^4.sin.(2. 3)meanlong. — 2.0  true  long. —  Jmean  anoin.)         [Ejection.]         6 

-j-     35',4....-j-     35',0.sin.(4.  5  mean  long. — 4.0 true  long. — 2.  J)  mean  anom.)  7 

-J-  124',G. ...-{-  123*,5.sin.(2. 3)mean  long. — ^2.0  true  long. —  j)  mean  anom.-|-0mean  anom.)  8 

-j-     47',6....-)-     46%5.sin.(2.  î)mean  long. — 2.0  true  long. —  ])  mean  anom. — 0  mean  anom.)  9 

-j-     39* ,3. ...-j-     42',0.sin.(])  mean  anom. — 0  mean  anom.)  10     inequali- 

ties in  tlio 

—  21',4.... —  22'',7.sin.(]) mean  long. — 0  true  long. —  5 mean  anom.)  11     i™n'"|'tuj<,, 

—  5S^G.... —  57*,4.sin.(2.  Jinean  long. — 2.0  true  long. — 2.])  mean  anom.)  12 
-|-  62',.5....+  60%4.sin.(2.mean  long,  of  ])  's  node — 2.0  true  long.)  (M)  13 
-(-  1I',5....4-  17',0.sin.(l>  mean  long. — 0  true  long.-j-0  mean  anom.)  14 
4-  4',9....-l-       3', I. sin. (  T)  mean  long. — 0  true  long. — 0  mean  anom.)                                 15 

—  4*',G.... —       3',7.sin.(2.3)mean  long. — 2.0  true  long.-)-2. 5  mean  anom.)  16 

—  10',6.... —     12',4.sin.(4.5mean  long. — 4.0  true  long. —  Draeananom.)  17 

—  6',4.... —  6',3.sin.(2.  3) mean  long. — 2. mean  long.  3) 's  node — 2.  ^mean  anom.)  18 

—  8^,8.... —  8%3.sin.(2.raean  long.  3)'s  node — 2.0  true  long.-}- 3)  mean  anom.)  19 
-j-  6',9....-|-  5',3. sin. (2. mean  long.  3) 's  node — 2.0  true  long. —  ])  mean  anom.)  20 
-j-  6%8....-j-  7'',7.sin.(meanlong.3)'s  node)  21 
_[-  2',6....-j-  0',0.sin.(2.  3)mean  long. — 2.0  true  long. — 2.0  mean  anom.)                       22 

—  2^,0.... —  0',0.sin.(3)mean  long. — 0  true  long— }- 3) mean  anom.)  23 
-J-  2%I. ...-]-  0%0.sin.(3.3)mean  anom. — 2.3)mean  long.-j-2.0  true  long.)  24 
-j-  2*,2....-|-  0',0.sin.(2.  ])  mean  long. — 2.0  true  long.-|-3)  mean  anom.-|-0mean  anom.)25 
-j-  l',3....-j-  0',0.sin.(2. 3)mean  long. — 2.0  true  long.-(-3)  mean  anom. — 0meananom.)26 
-j-  1»,1....-|-  0',0.sin.(4.  3)mean  long. — 4.0truelong. — 3. 3)  mean  anom.)  27 
-\-  l',2....-(-  0',0.sin.(2. 3)  mean  long. — 2.0trHe  long. — 2. 3)  mean  anom.-(-©mean  anom.)28 
-|-  1*, !....-(-  0',0.sin.(  3)  mean  long. — 0  true  long. —  3) mean  anom.-|-0  mean  anom.).  29 

VOL.  111.  162 


[5551] 


646  THEORY  OF  THE  MOON;  [Méc.  Ctl. 

Masonand   TiiG  811111  of  rU  tliGse  tcrms  must  be  added  to  the  moon's  mean  anomaly,  to 
[5j52]     which  we  must  also  add  the  function    A,    given  hy  the  equation, 

Coireclion 

of  the  By  Cuig.  By  IMasoii. 

àriiy.  J  =  — 1337^30 —  1302%0.sin.(©meananom.)  1 

[5553] 

—       1P,00 —       14^0.sin.(2.©  mean  anom.)  ;  2 

[5553']     ^^^^  ^^^  shall  obtain  the  moon's   corrected  anomaly,  bj  means  of  whicli  we 
aiwraa'yl'    iiiust  coiiipute  the  following  terms  ; 

Burç.  Mason. 

Equation  +22692%2 +22695S3.sin.( 5 corrected  anom.)  1 

of  the 

"""'•  +     776',4 +     777%0.sin. (2. 5  corrected  anom.)  2 

[5554]  „  (JV) 

4-       37%3 +       37%2.sin.(3. 3) corrected  anom.)    ^     ^      3 

+         2',0 +         2%0.sin. (4.1)  corrected  anom.).  4 

The  sum  of  the  terms  in  [5551,  5554]  must  be  added  to  the  moon's  mean 
Fk^f^-'      longitude,  and  we  shall  obtain  the  moon's  corrected  longitude,  which  must  be 

corrected  -,  .  i         r   ii  • 

longitude,    used  in  computing  the  toUowing  terms  ; 

Burg.  Mason. 

—  122  ,1 —  116%4.sin.(3)  corrected  long. — ©  true  long.)  1 

Variation     +2141%7 +2141%1  .sin.(2.  :j) corrccted  long — 2.©  true  long.)  2 

(P) 
[5556]      +       3%3 +       5%2.sin.(3. 3)  corrected  long. — 3.©  true  long.)  ^        3 

_j-        7'',3 +        8%8.sin.(4. 3  corrected  long. — 4.©  true  long.).         4 

Second       We    must  connect  the  terms   [5556]  with  the  corrected  longitude  of  the 

in°ngitude.    moon  [5555],  and  thus,  form  a  second  corrected  longitude,  to  which  we  must 

add  the  supplement  of  the  node,  or  the  whole  ciicumterence,  minus  the 

longitude  of  the  node.     We  must  also  add  to  it  the  function  B,  determined 

by  the  equation, 

Burir.  Mason. 

Correction 

^l^^"  B  =  +  540',0 +552%0.sin.(©  corrected  anom.)  ; 

[5558] 

[5558]  and  we  shall  obtain  the  moonh  distance  from  the  corrected  node.  We  must 
subtract  the  moon's  corrected  anomaly  from  the  double  of  this  distance,  and 

[5559]  multiply  the  sine  of  this  argument  by  —84^4,  according  to  Burg  ;  or,  by 
— 84',1,    according   to  Mason;   and  we   shall  get  another  inequality,  which 


VIT.  iv.s^ai.]    COMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


647 


we  must  add  to  the  inequalities  [5551,5554,5556].  Lastly,  we  must  add 
the  same  inequality  to  the  preceding  distance  of  the  moon  from  the  corrected 
node,  in  order  to  form  the  argument  of  latitude  ;  and,  we  must  multiply  the 
sine  of  double  this  argument  by  — 406',8,  according  to  Burg,  or,  by 
— 407',7,  according  to  Mason ,  and  we  shall  obtain  the  inequality  called  the 
reduction  to  the  ecliptic  ;  which  must  be  added  to  the  preceding  inequalities, 
to  obtain  the  longitude  of  the  moon,  counted  from  the  mean  vernal 
equinox.  We  must  here  observe,  that  the  7nean  longitudes  of  the  moon, 
of  its  node,  and  of  its  mean  anomaly,  must  he  corrected  for  the  seciilar 
inequalities. 

From  this  process  I  have  deduced  the  following  expression  of  the 
periodical  inequalities  of  the  moon's  mean  longitude,  developed  in  terms  of 
the  true  longitude,  counted  upon  the  ecliptic.  This  development  requires 
particular  attention,  to   prevent  the    omission  of  any  sensible  term.*     We 


Tables  of 
Mason  and 
Butg. 


[55G0] 

Argument 
oflatitude 

|.5r.Gii 

[5562] 

Reduction 
to  the 
ecliptic. 


[5563 


[5CG4] 


*  (3072)  We  shall  here  point  out  the  general  principles  of  the  method  of  developing 
the  functions  [5551 — 557.3],  in  the  forms  given  in  [5574 — 5579],  without  entering  into 
any  minute  numerical  details,  which  would  be  inconsistent  with  the  limits  of  the  present 
work.  In  the  first  place,  we  shall  show  how  the  functions  [5551, &:c.],  or  the  expression 
of  the  true  longitude,  maybe  reduced,  so  as  to  depend  wholly  on  the  mean  motions 
nt-{-s,  n't-\-i ,  &1C.  ;  noticing  the  secular  inequalities,  as  in  [5563],  but  omitting  any 
particular  reference  to  them  in  the  present  note  ;  and  then,  by  inverting  the  series,  we  can 
obtain  the  expression  of  the  mean  longitude  nt-{-s,  in  terms  of  the  true  longitude  v,  so  as  to 
conform  to  the  present  theory  [5095].  Several  of  the  functions  in  the  table  [5551]  do 
not  require  any  reductions;  as,  for  example,  those  in  [5551  lines  1,  2,  10,  &ic.],  which 
depend  on  the  mean  motions  ;  but,  in  those  inequalities  which  contain  the  sun's  true 
longitude,  we  must  substitute  its  value,  deduced  from  [668],  by  accenting  the  symbols  [5564t/] 
V,     e,     &.C.     to  conform  to  the  notation  used  in  this  theory  [4779'].     Hence  we  have, 


Sun's  true  longitude  v'^  sun's  mean  longitude  («'/-j-s')-}-e'  ; 

e'  being  used  for  brevity,  to  denote  the  periodical  terms  of  the  values  of  v  [668],  or  those 
which  depend  on  coefficients,  containing  the  excentricity  e'  and  its  powers,  multiplied  by 
sines  of  the  periodical  angles  ;  and,  it  may  be  represented  in  the  following  manner  ; 

e'=  2a'.sin.(îVi+p'). 

Now,  if  we  put  a,  for  the  coefficient  of  any  one  of  the  inequalities  [5551]  ;  T',  for  the 
part  of  the  argument  which  depends  on  the  mean  motions  ;    and    ze',  for  the  pari  of  the 


[5564a] 

[55C46] 
[5564c] 


[5564e] 

[5564/1 
[55G4g-] 

[5564A] 
[5564i] 


648 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 

have  neglected  those  inequalities  which  are  less  than  a  centesimal  second,  or 
0',324.     A  part  of  the  inequalities  of  this  expression  arise  merely  from  the 
[5564']     development  of  the  formula,  corresponding  to  the  process  in  Mason's  tables, 


Tables  of 
Mason  and 
Burg. 


same  argument,  depending  on    e'  ;    it  becomes  of  the  same  form  as  in  the  first  member  of 
[5564fe]     [5564Z].     Developing  this,  by  [21]  Int.,  we  get  the  second  member  of  [5564/]  ;   and,  by 
substituting  the  values  of  s'ln.ie',     cos.ie',  deduced  from  [43,44]  Int.,  we  obtain  [5564»i]  ; 

[5504/]  o.sin.(T'+te')  =  a.cos.ie'.sin.T'+a.sin.ie'.cos.T' 

[5564m]  =  a.  \  l—^.r-e'  S-j-^L.i^e'^— &c.  |  .sin.  T'+a.  {{e'—li^^+hc.  \  .cos.  T. 

Substituting,  in  this  last  expression,  the  value  of    e' ^=  lo.' .s\n.{i' n't~\-p')     [5564A],  and  its 

powers  ;  then  reducing  the  products,  by  means  of  [17 — 20]  Int.,  we  finally  get  the  value 

[5564n]    of    a.sm.(T'-{-ie'),     under  the  form  of  a  series  of  terms,  depending  exclusively  on   the 

mean  motions  ;  and  the  whole  function  [5551]  may  be  included  in  a  general  expression  of 

the  form, 

2a. sin. (p< +  7)   ; 


[5564o] 

[5564;)] 

[5564g] 

[5564r] 

[5564«] 

[5564<] 
[5564u] 

[5564u'] 


in  which  the  angles  depend  wholly  on  the  mean  motions.  If  we  substitute  this,  in  the 
expression  of  the  moon's  corrected  anomaly  [5553'],  we  get, 

3)  's  corrected  anomaly  =  3)  's  mean  anomaly  -J-  function  [5553]  -|-  2  a .  s\n.(pt-\-y). 

The  sine  of  this  expression,  or  the  sine  of  any  multiple  of  it  i,  which  occurs  in  [5554], 
may  be  developed,  as  in  the  general  formula  [5564?,  m],  by  putting, 

T  =  i.(3)'s  mean  anomaly)  ;         ie'==i.| function  [5553]+2a.sin.(p<+y)}. 

By  this  means  the  function  [5554]  may  be  made  to  depend  on  the  ?ne««  motions  ;  therefore, 
the  corrcc^ec?  longitude  of  the  moon  [5555]  will  also  be  given  in  terms  of  the  mean  motions. 
Substituting  these  in  [5556],  and  reducing,  by  a  similar  process  to  that  we  have  used,  we 
get,  as  in  [5556'],  the  moon's  longitude  iivice  corrected  ;  whence,  by  using  B  [5558], 
we  easily  obtain  the  corrected  distance  from  the  node  [5558'],  which  gives  the  correction 
[5559].  In  like  manner,  we  get  the  reduction  [5562]  ;  and,  finally,  obtain  the  true 
loni-itude  v,  expressed  in  terms  depending  on  the  mcara  motions;  and,  if  we  denote  the 
mean  longitude  by     nt-\-s  =  T,     the  expression  of  the  true  longitude    v,    may  be  put 

under  the  general  form, 

v=zT+J..B.sm.{iT-\-y); 

in  which  the  angles     {iT-\-y)     correspond  to  the  mean  motions. 

This  last  formula  may  be  inverted,  by  means  of  La  Grange's  theorem  [629c],  which,  by 
changing  -^a;  into  x,  then  x  into   T,  and  t  into  v,  becomes. 


Vll.iv.  <5-24.]     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION.  649 

which  we  have  just  explauied  ;  so  that    they  cannot  be  considered  as  the 
result  of  observation.     To    distinguish  the  different  inequalities,  we  have 
marked  with  an  asterisk  those   computed  by  Mason,  by  the  comparison  of     [5565] 
Bradley's  observations,  and  which  have  all  been   again  determined  by  Burg 
by  means  of  a  very  great  number  of  Maskelyne's  observations.      We  shall    ^^ 
commence  ivith  the  great    inequalilij  of  the  first  order  ;  and  then  shall  give,    '°"°""' 
successively,  the  five  inequalities  of  the  second  order,  the  fifteen  inequalities  of 
the  third  order,  and  all  the  inequalities  of  the  foxirth  and  of  higher  orders, 


1 

Inequali- 

in  tlio 
mooii*a 

icle. 


T:=v-\-F{T);         or         v=T—F{T);  [5564«] 

Comparing  together  the  values  of   v     [5564m,  «],  we  get, 

2B.sin.(iT+7)=— F(r);       whence,       F{v)  ^—SB. sin. (iv+j).  [5564x] 

Substituting  this  last  expression   in   [5564 w],   and  making  the  necessary  reductions,  we 
finally  obtain  the  values  of     T,     or     nt-{-s,     under  the  following  form  ; 

nt-{-s  =  u+2  C.sm.{iv-{-p)  ;  [5564y] 

which  is  the  same  as    in    [5096i],   neglecting,   as    in  [55646],  the    consideration  of  the 
secular  inequalities.     This  corresponds  with  the  results  in  [5574 — 5579]. 

A  similar  process  must  be  used,  in  reducing  the  expressions  of  the  latitude  [5595]  to  the 
form  [5596]  ;  or,  that  of  the  horizontal  parallax  [5603]  to  the  form  [5605].     There  are     [5564z] 
no  other  difficulties  in  performing  these  operations,  than  those  which  arise  from  the  great 
length    of  the   calculations,  in  consequence    of  the   numerous    equations,   which    require 
attention,  in  order  to  procure  accurate  results. 

In  applying  the  formula  [5564m]  to  most  of  the  small  inequalities  in  [5551, &ic.],  we 
may  neglect   the   square   and  higher    powers    of   e'.      For,    e'    is  nearly  equal    to     -j-'jf     [5565a] 

[5117  line  4];  hence  we  have     ae'^  =  -—-;     and,  if    tt<^100*,     as   is  the  case   with 

twenty-six   out  of  twenty-nine    of   the    inequalities    in    the    table    [5551],    it  becomes     [55656] 
ae'^<^0',0.3,     which  is    insensible.      Moreover,  in  the  equations  which  do  not    exceed 

12^    [5521  lines 2,  14— 29],  we  have     «e'  =  j^  <  0')2  ;      and    the  coefficient   of  the 

r5565c1 
corresponding  term  of  ae'.cos.T'  [5564m]  is  so  small,  that  it  may  be  frequently  neglected  ;     '■         ' 

and  then  we  may  put  simply     a.sin.T',     for     a.sm.{T'-{-ie'). 
VOL.  III.  163 


650 


THEORY  OF  THE  MOON 


[Méc.Cél 


[5566'] 


[5567] 


which  have  been  compared  ivith  observations  ;  lastly,  all  the  other  inequalities. 
We  shall  place,  in  the  second  column,  the  results  of  this  analysis;  and,  in  the 
third  column,  the  excess  of  the  numbers  in  the  second  column  above  those  in 
the  first.  In  the  fourth  column,  Ave  shall  give  the  excess  of  the  coefficients  of 
Burg's  new  tables,  reduced  to  the  same  form  as  in  this  theory,  over  those  of 
Mason's  tables  in  the  first  column.  Burg  retains,  in  his  tables,  the  same 
forms  of  the  arguments  as  in  Mason's  tables,  which  had  been  adopted  from 
the  tables  of  Mayer.  It  will  be  sufficiently  accurate,  in  reducing  Burg's 
tables  to  the  forms  of  the  present  theory,  to  apply  to  the  coefficients  of 
Mason's  tables,  thus  reduced,  as  in  the  first  column,  the  difiference  of  the 
corresponding  inequalities  in  the  two  primitive  tables,  taken  with  a  contrary 
sign.*  The  functions  A,  B  [5553,5558],  difler  a  little  in  these  two 
tables,  and  we  have  noticed  this  difference.  We  may  also  remark,  on  this 
point,  that,  by  introducing  in  the  primitive  tables,  an  inequality  in  the 
longitude,  depending  on 

[5568]  sin.(3)mean  anom.+ ©  mean  anom.)  ; 

and,  in  the  latitude,  an  inequality,  depending  on 

[5569]  sin. (argument  of  lat.+ ©  mean  anom.)  ; 

and,  making  the  necessary  changes  in  the  coefficients  of  the  inequalities, 
depending  on 


[5567'] 


[5567a] 


*  (3073)     If  we  suppose,  that  the  equation  [5564m]  corresponds  to  Mason's  tables  ;  and, 
that,  in  Burg's  tables,  one  of  the   coefficients    B,     is  changed  into     B-\-<iB;     it  will 
increase  the  second  member  of  the  ecpation  [5564j«]  by   the  quantity     Œ.sm.[iT-\-y'), 
which  is  very  nearly  equal  to     &B.sm.{iv-\-j).     Transposing  this  to  the  first  member  of 
'-  •'     the  same   equation,  we  find,  that  the  equation  [5564m],  corresponding  to  Burg's  tables, 

becomes, 

v—Œ.sm.{iv-Yy)  =T-\-J.B.Ûn.{iT-\-y)  ; 


[5567c] 


[5567rf] 


[5567e] 


which  may  be  derived  from  that  of  Mason  [5564m],  by  merely  changing  v  into 
D — Œ.sm.{iv-\-y)  ;  and,  if  we  make  the  same  change  in  [5564y],  which  results  from 
Mason's  tables,  we  get,  for  Burg's  tables,  the  following  expression  ; 

nt-\-B  =  V — 5B.sm.(iv-\-'y)-\-X  C.sin.(t«-|-|3). 

This  agrees  with  the  remarks  in   [5567']. 


Vll.iv4'24.]     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


6Ô1 


and,  on 


sin.(I>  mean  anoni. —  ©  mean  anom.); 


sin. (argument  of  lat. —  ©  mean  anom.), 


[5570] 
[5571] 


we  can  dispense  with  the  functions  A  and  B  ;    which  will  give  to  the  tables     r^^^y-^ 
a  greater  degree  of  uniformity.*     Burg  has  introduced  in  his  tables  of  the 


*  (3074)  If  we  put,  for  a  moment,  the  sun's  mean  anomaly  equal  to  s,  and  the 
moon's  mean  anomaly,  corrected  for  the  equations  [5551],  equal  to  m  ;  we  shall  have 
m-\-A  for  the  moon's  corrected  anomaly,  which  is  to  be  used  in  the  formulas  [5554]. 
Now,  if  we  put  C^  22692%2,  we  find,  that  the  first,  or  chief  term  of  [5554],  becomes 
as  in  the  first  member  of  [5571c];  and,  by  development,  using  [21,43,44]  Int.,  we  get, 
successively,  the  expressions  in  the  second  members  of  [5571c,  d]  ; 

Csln.(»i-f"^'^)  ^^  C.cos.A.sin.m-\-C.s\n.A.cos.m 

=  C.\l—iA^+^\A*—&ic.l.sm.m-\-C.\A—iA^+hc.\.cos.m. 

This  last  expression  may  be  considerably  simplified,  by  observing,  that  the  chief  term  of 
A  [5553  line  I],  expressed  in  parts  of  the  radius,  gives,  very  nearly, 

^  =  — 0,006.sin.s  ;     hence     i^2^0,000018.sin.25  =  0,000009— 0,000009.cos.2«; 
and  i^2c=0',2— O',2.cos.2s. 

This  last  expression,  being  multiplied  by  sln.m,  becomes  insensible  ;  consequently,  the 
equation  [5571(7]  may  be  put  under  the  form, 

Csin.(w+^)  =  C.sin.m-f-C/J.cos.m. 

If  we  suppose    ^'=1337',3,     ^"=ll',0,     the  expression  of   A  [5553]  becomes, 

A  = — yl'.sin.5 — A".s\n.'2s  ; 

substituting  this  in  [5571/],  and  reducing  by  [18]  Int.,  we  obtain, 

Csin.(m+^)^  C.sin.7?j — lA' C.js\n.(7n-\-s) — sin.(?K — s)^  J 

—iA"C.{sin.{m-i-2s)—sm.{m—2s)  ] .  2 

The  terms  in  the  second  line  of  this  equation  maybe  neglected;  for,  iC  [5571J], 
expressed  in  parts  of  the  radius,  is  nearly  equal  to  xV)  and  A"  =11'  [5571^]  ;  hence, 
^A"C  =  0',6;  which  is  nearly  insensible,  especially  when  multiplied  by  sin.(7n±2s)  ; 
therefore,  the  expression  [557  li]  becomes, 

C.sin.(7n+^)  =  C.s'mjn—^A'  C.sin.{m-]-s)-\-iA'  C.sm.{m—s). 


[5571a] 
[5.57  li] 


[5571c] 
[.5571  (/] 


[5571e] 


[5571/] 
[5571^] 

[5571ft] 

[5571i] 

[.5571  A] 

[557  J  i] 

[5571m] 


652 


THEORY  OF  THE  MOON 


[Méc.  Cél, 


[5572] 


[5573] 


Inequali- 
ties in  the 
moon's 
longitude. 


motion  in  longitude,  eight  new  inequalities,  which  are  not  given  in  the  reduced 
tables  of  Mason,  except  by  their  development.  We  have  distinguished  them 
by  a  double  asterisk.  Lastly,  he  has  compared  with  observation,  several 
inequalities,  which  he  has  found  to  be  insensible;  so  that  their  coefficients, 
given  by  the  development  of  Mason's  tables,  may  now  be  considered  as  the 
results  of  observation  ;  we  have  distinguished  these  by  a  triple  asterisk. 
We  may  thus  know,  by  mere  inspection,  the  inequalities  which  yet  remain  to 
be  compared  with  observation.  The  differences  between  the  two  taljles 
being  small,  enables  us  to  deduce  the  development  of  the  one  from  that  of 
the  other  ;  and  we  may,  by  the  inverse  method,  reduce  the  inequalities  of 
this  theory  to  the  form  of  Mayer's  tables. 


(Col.l.) 

Inequalities 
deduced  rioin 
Mason's  tables. 


(Col.  2.) 


(Col.  3.) 


(Col.  4.) 


Coefficients 

Kxcesg  of  tliuge 

Excess  of  the 

of  this 

coefficicn;s  over 

coefficients  of 

theory. 

those  of  Mason's 

Burg's  tables  over 

tables. 

those  of  Mason. 

Inequality  of  the  first  order. 
[.5574]      — 22677%5  .  sin.  (cv—^)* — 22677',5  ....  +0',0  .  .  .  .  +  3',1 


[5571ji] 


[5571o] 

[5571;)] 

[5571çl 


The  terms  of  this  equation,  depending  on  the  arguments  m±s,  are  as  in  [5568,5570]. 
The  substitution  of  the  values  of  the  multiples  of  m-\-A,  in  [555-1  lines  2 — 4],  produces 
only  some  small,  or  insensible  inequalities.  The  function  B  [5558]  being  small,  its  effects 
on  the  equations  [5559,  5560]  are  nearly  insensible  ;  but,  they  might  be  noticed,  in  a 
similar  manner  to  that  in  [5571ot,&;c.]. 

In  like  manner,  if  we  suppose  the  argument  of  the  latitude  to  be  represented  by 
m'-\-B,  and  the  coefficient  of  the  first  term  of  the  expression  of  the  latitude  by  C"  ;  so 
that  the  term  itself  becomes  C'.sm.{m'-\-B)  [5595  line  1];  we  may  develop  it  in  the 
same  form  as  in  [5571i]  ;  namely, 

C.  sin.(w!'+B)  =  C'.sin.m'— ABC.  \  sin.(TO'+s)— sin.(w'— s)  \  ; 

in  which  the  terms  depending  on  the  angles  m'±5,  are  as  in  [.55G9,  5571].  The  e fleet 
of  the  rest  of  the  terms  depending  on  B,  is  so  small,  that  they  are  hardly  deserving  of 
notice. 


*  (.3075)     The  author  remarks  in  a  note  upon  this  part  of  the  work,  that  the  coeflîcient 
[5574o]     of  the  inequality  [5574],  is  one  of  the  arbitrary  terms  of  the  theory,  and  he  has  thought 
it  best  to  adopt  the  result  of  Burg. 


Vll.iv.  §24.]    COMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


653 


(Col.  1.) 

Inequnlilies 
(lcduce-1  from 
Masoii*s  tables. 


(CoI.i2  ) 


(Col.  3.) 


(Col.  4.) 


Coeflicionts 

Excess  of  these 

Excess  of  the 

of  this 

coetriciente  over 

cooJficii'iits  of 

theory. 

those  of  Muson's 

Burg's  tables  over 

tables. 

those  of  Mason. 

Tables 
of  Mason 
and  Burg. 


Inequalities  of  the  second  order. 

4-  462%5.sin.(2c»— 2ro)* +  467',4  .  .  . 

—\903',4.sm.{2v—2mv)* — 1897%4  .  .  . 

— 4681^5.sin.(2v— 27»!'— ci'+to)* — 4G85'',5  .  .  . 

+  672',5.sin.(cW— s:')* +  6S2',4  .  .  . 

+  407',l.sin.(2_g-u— 2Ô)* +  40G',9   .  .  . 

Inequalities  of  the  third  order. 

—  10*,7.sin.(3cD— Sîi)* —  l  r,4  .  .  . 

+  6V,l.sm.{2gv—cv—2ê-{-iz)* +  66',4  .  .  . 

—  22',4.sin.(2^v+ct)-2â— Tï)*** _  23',0   .  .  . 

4-14G^0.sin.(2y— 2mu-f-cw— a)* +147%0  .  .  . 

+  I4^5.sin.(21;— 2mi;+c'?ni'— in')* -{-   13%6  .  .  . 

— 136',5.sin.(2« — 2mv — c'tod+ct')* — 134',5  .  .  . 

-(-  2P,7.sin.(2u — 2mv — cv-{-c'mv-\--ui—ui')*.  .  .  .  +  24%3  .  .  . 
— 20b',S.sm.(2v—2mv—cv — c'mv-j-u-\-a')*.  .  .  .  — 205%8  .  .  . 

+  68',6.sin.(r«4-c'mîJ — z-.—a')* -f  7P,0  .  .  . 

— l\.6%8.sin.{cv—cfmv — ra-(-a')* — 117'',3  .  .  . 

-f  178^6.sin.(2cj; — 2v+2mv—2-a)* -}-IC9%l   .  .  . 

4-  55\S.sm.{2gv—2v+2mv—2é)* -f  56',6  .  .  . 

-\-     6',9.sm.{2dmv—2zi')* -}-    10', 1   .  .  . 

-|-116',7.sin.(t; — mv)* +122',0.(l-f- 

—  19',0.sin.(i; — mv-\-c'mv — zi')* —   IS',8.(I  + 


+4',9  . 
+G%0  . 
—4^0  . 
+9',9  . 
—0^2  .  , 


— 0',7 
+  5',3 
— 0',6 
+1%0 
— 0^,9 
+2',0 
+2%6 
— 0%0 

+2^4 

—0^5 
—  9^5 

+œ,8 
+r,2 


+0',6  1 

— 0',6  2 

— l',I  3 

+3',2  4 

— 0»-,9  5 


)■ 


—0,1  1 

+0%3  2 

+0',0  3 

+0',0  4 

+2%0  5 

—V,2  6 

— l',l  7 

—  V,l  8 
+  1VJ  9 
+0',8  10 

—  P,2  11 
+2%!  12 

—  2^9  13 
+5%7  14 
+5',5  15 


[5575] 


Inequali- 
ties in 
tlie  moon's 
longitude 
reduced  to 
the  form 
of  the 
present 
theory. 


[5576] 


VOL.  III. 


164 


654  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

Table,  of  (Col.l.)  (Col.  2.)  (Col.  3.)  (Col.  4.) 

Mason  and  ,  ,.  . 

gyp„^  Inequalities 

°  ili)rlii<>iii1     fm 


[5577] 


deduced  from 
Mason's  tables. 


Coefficients 

Excess  of  these 

Excess  of  the 

of  this 

coefficients  over 

coefficients  of 

theory. 

those  of  Mason's 

Burg's  tables  over 

tables. 

those  of  MasoD. 

Inequalities  of  the  fourth  order,  and  of  higher  orders,  which  have  been 
compared  loith  observations. 

—  0',3.sin.(4cy— 4îï)* +0^0     1 

—  2',0.sm.[2gv—2cv—2ô-\-2Ts)* 4-0'',l     2 

+  l^l.sm.igv—v—ê)* +  ô^G  ....  — 2',1   .  . 

—  7%0.sin.(3!; — 3mv)* 

-(-  5'',7.sin.(4i; — 4mv)* 

4-  0%S.sin.(ct)+2c'ff8V — -m — 2«')* 


Inequali' 

ties  in  the     _  0',8.sin.(CT— 2c'm«— «+2^')* 


raoon'a 
longitude 
reduced  to 
the  form 
of  the 
present 
theory. 


— 0%9 

3 

+  1%9 

4 

+P,5 

5 

— 0',2 

6 

+0',2 

7 

+0',9 

8 

+  1'=8 

9 

[5578] 


—  S',9.s\n.{2cv-]-2v—2mv—2'a)* —  S',1   ....  -}-0',S  .  , 

+28%9.sin.(4»— 4??iî;— c«+ra)* +33%4 +4%5  .  . 

+15',2.sin.(4D— 4mu— 2c«+2t3)* +15',5 +0',3 — 0",4  10 

—n',0.am.{cv—v-{-mv—^)* —  8',3.(14-i) +1",3  11 

l',l.sin.(» — mv — c'mv+vi')* — l',S  12 

-f  Ç)\b.sm.{2v—2mv—2gv+cv-{-2ô—-a)* +  8',7 — 0',8 +0',5  13 

-f  l',2.sm.{2gv+cv~2v-}-2mv—2ê—zs)* 4-l',G  14 

—  '3',ô.sm.(2v—2mv—2cfmv+2i^')** — 2',6  15 

_  5%9.sin.(CT+«— 7««— ra)** —   5-,0.(l+i) -f2%G  16 

+   l',0.sm.(3cv—2v+2mv—2-a)** — 2',1  17 

4-  0',6.sin.(2« — 2mi>+CT-|-c'wi'— « — to')** — 2',2  18 

+  12',8.sm.{2î)— 2mv+CT— c'nu-— «+to')** +10%2 — 2',6 — 1',3  19 

+  0%S.sm.{4v—4mv—3cv—Qzs)** — 1»,I  20 

4-  l',0.sm.{2cv—2v-\-2mv—c'mv—2-us-{-vi')** —  0',2  ....  — P,2  ....  +1',2  21 

-|-  V,3.s\n.{cv—v-^mv—cmv — •n+a')** +!',!   22 

-I-  G',4.sm.{2cv—2v+2mv-\-cmv—2-!S—m')***.  .  .  +  5',9 — 0',5            _  23 

l',2.sin.(4D— 4mt)4-ct;— w)***  24 

-j-  0',2.sin.(4c« — 4v-\-4:mv — 4ra)***  25 

—  3",9.sm.(2D— 2mt)+2^jJ— 2^)***  26 
±    V,l.sm.(2gv±c'mv—2ê=P-!s')***  27 

—  Û',3.sin.(2gj;+2ci)— 2D+2mi)— 2é— 2a)***  28 
±  2%0.sm.{2gv—2v-\-2mv±cmv—2ê^zi')***.  29 


VII.iv.§24.]     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


655 


(Col.  1.) 

Inoqualities 
deduced  from 
Mason's  lables. 


(Col.  2.) 

(^oofficiollts 
ol'  this 
tlieory. 


(Col.  3.) 

Excess  of  these 
coefficients  over 
ttiose  of  Mason's 
tables. 


Tables  of 
Mason  and 
Buig. 


Inequalities  of  the  fourth  order,  and  of  a  higher  order,  deduced  from  Mason's 
tables,  which  have  not  been  compared  loith  observations. 


-{-5',0.s\n.{2cv—cmv—2^-\-^') 

—2',8.sm.{2cv+c'mv—2zi—-!s') 

-|-4%7.sin.(4i; — 4mv—cv — c'mv-\-zi-{-^') 
— 4',5.sin.(2« — 2mv-\-2gv—cv — 2d+w) 
— 0',4.sin.(2v — 2mv — 2^i'-f-2cw+2<)— 2ra) 
-|-l'',9.sin.(4w — 4mu — 2cv-{-c'mv-{-2zs — ^') 
-|-l»,6.sin.(4w — 4m« — 2cv — c'mv-{-2-ss-\-zi') 
— l'',2.sin.(3î)— 3mD— ci'+w) 
+0',8.sm.{4gv—4è) 

4-3',0.sin.(2i; — 2mv—cv-\-2c'mv-\-Ta — 2ct') 
— 5',8.sin.(2t' — 2mv — cv — 2c'mv-\-ui-\-2zi') 
-|-0',5.sin.(4i' — 4mv — 2gv — fy+2â-[-ra) 


+4',5 


-0",5 
-0',4 


-. igv-cv+2é+^) 

0',5.sin.(4i' — 4mt) — c 

imv — 3cv-\-3t!s) 


■c'mv+zi') 


-]-0',7.sin.  (6v — 6mu — oti;-t-ora 
•0',4.sin.(cD — v-\-mv-\-c!mv — 

n>  Q  o;,,    ^1,. Am„J-^'„,„ -,' 


-|-0',3.sin.(4D — 4mv-\-c'mv  — 


-') 


0- 


1 

2 

3 

4 

5 

G 

7 

8 

9 

10 

11 

12 

13 

14 

15 

16 


Inequali- 
ties in  ihe 
moon's 
longitude 
reduced  to 
the  form 
of  the 
present 
theory. 


[5579] 


We  see  by  this  table,  that  the  greatest  difference  between  the  coefficients 
of  Mason's  tables  and  those  of  the  theory,  is  9%9  ;    and,  there  is  only  8%3      rsggoi 
between  the  theory  and  Burg's  tables.   We  might  make  this  difference  vanish 
by  carrying  on  the  approximations  to   terms  of  a  higher  order  ;    but,  the 
preceding  comparison  is  sufficient  to  establish  incontestibhj,  that  the  general     [5580'] 
laio  of  gravitation  is  the  only  cause  of  all  the  moon's  inequalities. 

Two   of  these    inequalities,    on   account   of  their  importance,    must  be 
determined   with  particular   care.       The  first   is  that  lohich  is    called    the      [558I] 
parallactic  inequality,    whose   argument    is     v — mv.       It  depends  on  the    Paraiiae- 
sua's  parallax.     It  has  been  determined  by  carrying  on  the  approximation  to    <i™i"j- 
quantities  of  the  fitth  order  inclusively  ;  so  that  we  have  reason  to  suppose. 


656  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


b 


that   the  value    whicli    we   have    obtained,  is    very    accurate.       According 

to  Mason's  tables,  reduced  to  the  form  of  the  present  theory,  this 
[5582]      inequality  is  equal  to  116',7  [5576  line  14]  ;  but  Burg,  who  has  determined 

it  by  the  comparison  of  a  very  great  number  of  observations,  finds  it  to  be 
[5583]  greater  by  5',7  [5576]  ;  therefore,  it  is  equal  to  122',4.*  Putting  this 
[5584]      last  result  equal  to  the   coefficient     (l+i)A22%0,     which  is  given  by  the 

theory  in  [5220  line 21],  we  obtain,t 


*  (3076)  In  ihe  Monatliche  Correspondenz,  vol.  28,  page  101,  is  given  an  extract  of 
a  letter  from   Burckhardt,  containing  some  remarks  on  the  effect  of  an  erroneous  estimate 

[5583a]  of  the  moon's  semi-diameter,  in  determining  the  value  of  the  coefficient  of  the  parallactic 
inequality.  The  usual  method  of  determining  the  moon's  place,  by  observation,  is,  by 
ascertaining  the  difference  between  the  time  of  the  transit  of  the  moon's  enlightened  limb, 
over  the  meridian,  and  that  of  some  well  known  fixed  star.  In  tliis  method,  the  moon's 
we«<e™  limb  is  observed,  when  the  angle  v—mv  is  less  than  180'',  or  sin.(y — mv) 
is   positive;    but,    the   eastern    limb   is    observed,    when     v  —  mv     exceeds     ISO"*,     or 

[5583i]     gjj,  /^ ,^jy)     ig  negative.     Now,  it  is  evident,  that,  if  there  be  an  error  in  the  estimated 

value  of  the  moon's  semi-diameter,  and,  that  it  be  taken,  for  example,  too  great  by  P,  the 
longitude  of  the  moon's  centre,  resulting  from  this  observation,  will  be  increasedhy  nearly 
the  same  quantity,  when     sin.(v — mv)     is  positive,  and  decreased,  when     sm.{v — mv)  is 

[5583c]  nerrative  ;  consequently,  the  error  of  the  moon's  longitude,  arising  from  this  source,  will 
always  have  the  sa7ne  sign  as  the  parallactic  inequality,  and  it  will  be  impossible  to 
separate  these  two  quantities.     From  this  we  easily  perceive,  that  it  is  of  great  importance, 

[5583rf]  j^  ascertaining  the  coefficient  of  the  parallactic  inequality,  to  have  the  moon's  semi- 
diameter,  to  the   utmost   degree  of  accuracy.     Burckhardt  supposes,   that  it  is  owing,  in 

[5583e]  g^^^^^  measure,  to  this  circumstance,  that  Mayer's  first  estimate,  given  in  his  lunar  theory, 
which   was   published  by  the    Commissioners  of  Longitude    of  Great  Britain,  in    1757, 

[5583/]  j^f^^gg  tiiis  coefficient  only  115'  ;  being  less  by  7',4,  than  the  late  accurate  determination 
of  Burg. 


[5584a] 


1(3077)  We  have,  in  [5584],  (l+i).122%0  =  122^4.  Dividing  this  by  122',0, 
we  get  1+i  =  1,003  nearly,  as  in  [5585]  ;  the  slight  difference  arises  from  the  use  of 
the  centesimal  division  to  two  or  three  more  places  of  decimals;  hence,  [5221]  becomes. 


a  1,003  .        rrco/'l 

[55841]  â'^^ÔT'     ^'  '"   [^^^^]- 


[  5584c] 


Now,    the    moon's  mean   horizontal  parallax  is  nearly     -     [5309]  ;  and,  in  like  manner, 
the  sun's  horizontal  parallax  is, 


VII.  iv.<5.24.]    COxMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


657 


therefore, 


l  +  t=  1,002985; 


a  _  1,00-2985 
n'  ~~  ""400""  ■ 


Now,  the  sun's  parallax  is     —,     or     — .-:    therefore, it  may  be  represented 

a'  a    a 

by, 


D    1,002985 


=  sun's  parallax. 


Substituting  for 


D 


its  value 


0,01655101 


[5329],  we  get     8',56  for 

the  sun's  mean  parallax  upon  the  parallel,  in  which  the  square  of  the  sine  of 
the  latitude  is  ^  ;  which  is  very  nearly  the  same  as  has  been  found  by 
astronomers,  from  the  last  transit  of  Venus  [5589^,  A;].  Hence  it  appears, 
that  the  hinar  theory  furnishes  a  very  accurate  method  of  determining  the 
sunh  parallax.* 


[5585] 


[5586] 


[5587] 


[5588] 

Uetermin- 
ation  of 

[5589] 

the  sun's 
parallax, 
by  means 
of  this 
Junnr  iri- 
equatity. 

[5589'] 


D 

a'' 


D    a 

a    a' 


D     1,003 


a       400 


,     as  in  [5588],  nearly. 


D 


[5584rf] 


Substituting  in  this,  the  value  of    —      [5.329],  and,  multiplying  by  the  radius  in  seconds 
206265',   it  becomes    8',56,   as  in  [5489]. 

*  (.3078)  We  may  observe,  that  the  author,  in  vol.5  [12737],  states  the  well  known 
fact,  that  this  method  of  determining  the  sun's  parallax,  by  means  of  the  parallactic  [ssggai 
inequality,  was  given  by  Mayer,  in  page  50  of  his  lunar  theory  [5583e],  almost  fifty 
years  before  the  first  publication  of  this  volume  of  the  Mécanique  Céleste.  According  to 
Mayer's  calculations,  from  the  theory,  the  sun's  parallax  lO'.S  corresponds  to  a 
parallactic  coefficient  of  158'',6  ;  consequently,  the  parallax  8', 56  corresponds  to 
125',7,  instead  of  122',4,  wiiich  is  used  by  La  Place.  Mayer  supposes  this  coefficient 
to  be,  by  observation,  only  115%  corresponding  to  the  parallax  7'',8.  If  he  had 
used  the  same  coefficient  122", 4  as  La  Place,  the  result  of  his  theory  would  make  the 
parallax  8',3  ;  which  differs  but  little  from  the  truth  ;  and  proves,  that  Mayer  had 
carried  on  his  approximations  to  a  considerable  degree  of  accuracy,  in  computing  the  value 
of  this  inequality  by  the  theory. 

Before  closing  this  note  we  may  remark,  that  Messrs.  Carlini  and  Plana  have  given,  in 
Zach's  Correspondance  Astronomique,  for  the  year  1320,  page  26,  a  calculation  of  the 

VOL.  III.  165 


[55895] 

[5589c] 
[5589rf] 


658  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 


[5590] 


The  second  inequality  is  that  which  depends  on  the  longitude  of  the  node  oj 
the  lunar  orbit,  or,  on  the  argument  gv — v — ('.  Its  coefficient,  according 
to  Mason,  is  7,7  [6578  line  3];  but  Burg,  who  has  just  determined  it, 
[5590']  by  a  very  great  number  of  observations,  reduces  it  to  6%8  [5578  line  3]. 
[5591]  The  theory  gives  5',552  [5390],  if  Ave  suppose  the  earth's  oblatencss  to 
[5592]  be  -^\j  ;  or,  1P,499  if  the  oblateness  be  -^j^-^.  Hence  it  is  evident,  that 
[5593]  Burg's  computation  corresponds  to  the  oblateness*  ■j-ôi,-âT'  This  inequality 
Oblateness  is  determined  ivith  great  precision  by  the  theory  :  and,  we  have  no  reason  to 
e°nrth!        suppose,  that   there   is,  with  respect  to   it,  the  same  degree  of  uncertainty, 


[5589e]  sun's  parallax,  b)'  this  method,  making  it  8',719.  On  the  other  hand,  La  Place,  in  reviewing 
his  calculations,  in  a  paper  presented  to  the  Board  of  Longitude  oJ  France,  January  19, 

[5589/]  1820,  and  printed  in  the  Connaissance  des  Terns,  for  1823,  page  230,  makes  it  S',65. 
In  his  fiftl)  and  last  edition  of  the  Système  chi  Monde,  page  230,  he  finally  adopts  the  value 
26",58  =  8',6L     This   differs  but  very  little  from  the  value     8',62     given  by  Burg,   in  a 

'■  ^  late  investigation,  published  in  1826,  in  vol.  iv.  page  24,  of  Schumacher's  Astronomische 
Nachrichten.     Finally,  we  may  remark,  tliat  these  results  difler  but  very  little  from  those 

[5589ft]  which  are  obtained  from  the  transits  of  Venus  in  1761  and  1769.  These  observations 
have  been  lately  discussed  with  great  care,  by  Encke,  using  the  most  approved  tables  ; 
and,  in  a  work  entitled,  "Die  Entfernung  der  Sonne  von  der  Erde  aus  dcm  Venusdurchgange 

[5589i]  ^Q„  1761^"  page  143,  he  gives  the  parallax  from  8',43  to  8',55  ;  by  combining,  in 
the  best  manner,  the  diflerent  observations  of  the  transit  of  1761.     The  results  of  the 

[55894]  observations  of  the  transit  of  1769,  are  given  from  8',56  to  8°,65,  in  vol.  iv.  page  25, 
of  Schumacher's  Astronomische  Nachrichten;  and  the  final  result  8', 5776  is  used  in 
computing  the  Nautical  Almanac  for  1834.  In  conclusion,  we  may  observe,  that,  in  the 
year   1763,  a  work  was  published  by  Doctor  Matthew  Stewart,  entitled,  "  The  Distance 

'^"'  ■'  of  the  Sun  from  the  Earth  Determined  by  the  Tlicory  of  Gravity,  ^c,"  by  means  of 
the  observed  motion  of  the  moon's  apsides.  This  method,  though  it  has  been  approved 
by  Horsley,  Play  fair,  Hutton,  and  others,  is  essentially    erroneous   and  defective  ;  as  is 

[5589jn]  shown  in  a  jjaper  presented  by  me  to  the  American  Academy  of  Arts  and  Sciences,  and 
published  in  the  fourth  volume  of  the  first  series  of  their  Memoirs. 

*  (3079)     This  is  easily  deduced  from  the  formula  [5390e],  by  substituting     ^'^6',8 
[5590',  5390a— e],  which  gives, 

6%8-|-7',6  1 

L5593a]  ''-P  =     4392',6     =  3Ô5;Ô5'      "^'"■'^- 

This  result  is  finally  retained  by  the  author,  in  page  230  of  the  fifth  edition  of  his  Système 
du  Monde. 


VII.iv.§25.j     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION.  659 


which  prevails  in  most  of  the  other  coefficients  of  the  lunar  theory,  by  reason  [5593] 

of  the     slow    convergency    of    the    approximations.     As  this  inequality  is  aucfn™'"" 

oftlic 

proportional   to  the  oblateness  of  the  earth,  it  deserves  the  greatest  attention  Jii^'^^^"""'' 

of  astronomers.     It  follon-s  incontestibly,  from  the  values  assigned  to  it  by  bemoan? 

Mason    and    Burg,   that  the   earth   is  less  fattened,  than  in  the   case    of  i;;X"''''' 
homogeneity.       This   is   conformable  to  what  has  been  deduced  from  other 
phenomena,  in  books  iii.,  iv.,  v. 


longitude 

[5594] 


25.  We  shall  now  consider  the  moon'' s  motion  in  latitude.  It  is  found 
by  the  tables  in  the  following  manner.  If  we  call  the  moon\s  corrected 
longitude,  the  mean  longitude  added  to  all  the  inequalities,  except  the 
inequality  of  the  reduction,  we  shall  find  that  the  moon's  latitude  is  represented 
by  the  folloiving  expression  ; 


+  18520',8  ...  +18524%5  .  sin. (argument  of  latitude)  1 

—         5%0  ...  —  4',4  .sin. (3. argument  of  latitude)  2 

+     528',4...    +     528',4.  sin.  (2  3)  corrected  long. —  2©  true  long. —  arg.  lat.)  3 


4-        n%6  ...   +        17%6  .  sin.(arg.  lat. —  3)  mean  anom.)  5 

-j-       25',1    ...   -f-        2.5',1  .sin.(25mean  anom.— arg.Iat.)  6 

[Moon's  latitude.] 

-\-  r,9  ...  +  r,9.  sin.(.33)mean  anom. —  arg.  lat.)                                                 7 

+  9'',0  ...+  9',0  .sin.(2Dcorr.long.-2©truelong.-arg.lat.+©niean  anom.)  8 

+  3',7  ...  +  S",?  .sin. (23)corr.long.-2©true  long.-arg.lat.-©mean  anom.)   9 

-f  2',2  ...   +  2",2  .sin. (2Dcorr.long.-2@truelong.-arg. lat. +  I»mean  anom. )10 

+  15'.9  . . .   +  15',9  .sin.(arg.lat.-f-3)mean  anom.-2l)corr.lon.-|-2©true  long.)ll 

-f-  5',2  .  .  .   +  5',2.sin.(arg.lat.-|-2])meananom-23)cor-lon.-t-2©truelong.)I2 

—  8',0  ...   —  0',0.  sin.  (3)  corrected  longitude).                                                      13 

Reducing  these  formulas  to  sines  of  angles,  which  vary  in  proportion  to  v, 
we  obtain  the  following  results  ; 


[5594'] 


Tables 
of  the 
moon'ê 


—  f3,l    ...  —  o  jl  .sin.(arg.  lal. —  ©  mean  anoni.)  4     i^^tiiude, 

'  by  Burg 

and 


Mason. 


[5595] 


660 


THEORY  OF  THE  MOON  ; 


[Méc.  Cél. 


(Col.  10 

Inequalities 
deduced  from 
Mason's  tables. 


iCol.  9.) 

Coefficients 
of  this 
theorj. 


Inequali- 
ties in  the 
moon's 
latitude, 
reduced  to 
the  form 
of  the 
present 
theory. 


[5596] 


(Col.  3.) 

Excess  of  tliese 
coefficienis  over 
those  of  Mttson*s 
tahlea. 


(Col.  4.) 

Excess  of  the 
coefficients  of 
Burg's  lahlcs  over 
those  of  Mason. 


18543',9.sin.(g'«— «)* 18542%8  . 

+  13%9.sin.(3^«— 3^)* +  12%6  . 

-{-52T,2.sm.{2v—2mv—gv-{-^)* +525',2 

+     0',7.sin.(2t)— 2mî;+^u— 0) +     l',l 

—  4%l.s\n.{gv-\-cv—ê—zr)* —     5',6 

+   19%8.sin.(gD— cu-ô+zs)* +  19',8 

-f  2V,l.sm.{gv-\-cv—2v-\-2mv—ê—z:s)* +  2r,6 

—  0',8.s\n.{2v—2mv-{-gv—cv—ê-}-a) —     r,4 

+     6%0.sin.(2i;— 2m«— ^y+cj;+é— «)* +     6%5 

+  24\8.sm.(gv-{-c'mv—ê—zs')* +  24%3 

—  2T,9.sm.{gv—c'mv—ê+zs')* —  25%9 

—  9\5.s\n.(2v—2mv—gv+c'mv-\-ê—a')*.  ...  —  10',2 
+  22',2.sm.{2v—2mv—gv—c'7nv-^ê-\-z!')*.  .   .   •   +  22%4 

-j-  25',7.sin.(2cD— g-i'— 2î3+â)* +  27',4 

+     4%3.5m-(2cv-{-gv—2v+2mv—2zi—ê)*    .  .  .  +     5',1 

_     0',9.sin.(3c«— ^v— 3ra+â)* -0',0  16 

+     r,0.sm.{3gv—2v+2mv—3ê) +0%0  17 

-|-     0%4.sin.(4î)— 4mï— ^t)+fl) +0%0  18 

-I-     (y,6.sm.{3cv—gv—2v+2mv—3-^+ê) +0',0  19 

±     0', 6. sin. {cv'\-gv — 2v-{-2mv±:c'mv—zi—ê^-^) +0',0  20 

T     0%6.sin.(2ci;+^« — 2v-{-2nv±:Cv—2ia—ê^-!:s)  21 

+     0',9.sm.{4v—4m,v—gv — ct+^+to) +0%0  22 

—  0»,0.sin.(3)'s  true  longitude)** —     6',5 — 8%0  23 

Here  the  theory  agrees  better  with  observation,  than  it  does  in  the  case 
relative  to  the  moon's  motion  in  longitude.     This  happens,  in  consequence 


— IM  . 
— r,3  . 

,  — 2',0 

,  +0',4 
— 1%5 

•  +0',0 
.  — 0',1 
.  — 0%6 

.  +œ,5 

.  —  0',5 

.  +2^o 

.  — 0%7 

•  +0',2 

•  +1%7 
.  +0',8 


— 3',7*  1 

— 0-,6  2 

-|-0^0  3 

+  0^0  4 

+0'',0  5 

+0',0  6 

4-0^0  7 

+0'',0  8 

+0',0  9 

—  0',5  10 

+0'',5  11 

— 0',0  12 

-[-0',0  13 

+0",0  14 

-t-0%0  15 


*  (3080)     In  a  note  on    this  table,  the    author  remarks,    that  the  coefficient  of  the 
inequality  [5596 line  1],  is  one    of  the  arbitrary   quantities  of  the  theory;    and,  that  he 
[5.596a]     gj^gg  jj^g  preference  to  the  result  of  Burg's  calculation. 


VII.iv.>5.-25.]     COMPARISON  OF  THE  THEORY  WITH  OBSERVATION.  661 


[5596'] 


of  the  greater  simplicity  in  the  approximations  of  the  motions  in  latitude, 
which  renders  the  results  more  accurate.  For  tliis  reason,  1  have  thought 
it  best  to  compute  the  tables  of  the  motion  in  latitude,  strictly  by  the 
theory  ;  so  as  to  reduce,  as  much  as  is  possible,  the  whole  science  of 
astronomy  to  the  single  princij)le  of  universal  gravitation.  The  inequality, 

—  6',487  .  sin.  (5  's  true  longitude)     [5357],  [5597] 

is  not  introduced  into  Mason's  tables,  but  was  discovered  by  me,  by  the 
theory  ;  and  is  now  confirmed  by  observation,  in  an  incontestible  manner. 
Burg  found  it  to  be  equal   to, 

—  8',0  .  sin.(3)'s  true  longitude),  [5598] 

by  the  comparison   of  a  very   great  number   of   Maskeline's   observations. 

This  coefficient  is, 

—  6^487     [5357],  [55991 

if  we  suppose  the  oblateness  of  the  earth  to  be    ^^^  ;     it  will  become, 

—13',  436     [5358],  [5600] 

if  the  oblateness  be  -jl-g,  as  in  the  case  of  the  homogeneity  of  the  earth. 
Hence  it  is  evident,  that  the  coefficient     — 8%     which  is  found  by  Burg,      [5601] 

corresponds  to  the  oblateness .*      It    is    veni    remarkable,     that    this      [5602] 

^  304,6  "^  Doletrain- 

ation 

inequality  gives  the  same    oblateness   as   the   inequality   in   the  motion   in    oblateness 

ofthe 

longitude,  depending  on   the   sine   of  the  longitude  of  the  node,  which  toe  ^^ymeans 

have   given  in  [5593].     These   tivo  inequalities,  which,  by   the    light    they  ("ne^naiity 

throrv  on  the  figure  of  the  earth,  deserve  the  utmost  attention  of  observers,  '[seoan 
unite   in   the    exclusion    of  the   homogeneity  of  the  earth. 


*  (3081)     Substituting  in  [5357c],  the  value  of  ^  =  8'  [5601],  it  becomes, 

_  8'+8%88  _      1 
'^'  5Ï32^9    ~  304,1  '  [5602a] 

which  is  nearly  the  same  as  in  [5602]  ;  the  slight  difference  arises  from  the  use  of 
centesimal  seconds  to  a  greater  number  of  decimals.  The  result  given  in  [5602],  is  used 
by  the  author,  in  page  229,  of  the  fifth  edition  of  his  Système  du  Monde. 

VOL.  III.  166 


662  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

26.  It  noiv  remaiiiH  to  consider  the  moon^s  horizontal  parallax.  The 
following  is  the  expression  of  that  parallax,  at  the  equator,  according  to 
the  tables  of  Mason  and  Burg  ; 

(Col.  1.)  (Cui.a  ) 

nuig.  Mason  and  Mayer. 

342F,0  . . .    3431^4  1 

—  0',3  ...  —  0^3.cos.(©'s  mean  anom.)  2 
-f-  0'',7  .  .  . -(-  O',7.cos.(2.3) 's  mean  long. — 2.©  true  long. -|-(v)  mean  anom.)  3 
-j-     0',8  ■■■-{-     0>',8.cos.(2.  ]>  mean  long. — 2.©  true  long. — ©  mean  anom.)  4 

—  0*,1  •  •  • —     O',l.cos.(2.3)  mean  long. — 2. @  true  long.-)- 3)  mean  anom.)  5 

Tables 

ofihe  _|_  37s  :5  .  . . -J_  37'',3.cos.  (2.1)  mean  long. — 2.©  true  lon<T. —  l)meananom.)         [Eveciion.]         6 

moon's  '  o  V.'  o  / 

paiaiia.x,'      -j-     0%3  ■••-!-     0%3.cos.(4.  3)mean  long. — 4. ©true  long. — 2.  J)  mean  anom.)  7 

by  Burg, 

amf""         -|-     I'jfl  .  . . -j-     l'',0.cos.(2.  J)mean  long. — 2,©  true  long. —  1)  mean  anom.-)-©  mean  anom.)  8 

Mayer. 

-\-     0',()  .  ■  •  -|-     0%6.cos.(2.  3)  mean  long. — 2.©  true  long. —  j)  mean  anom. — ©  mean  anom.)  9 

-)-     0',2...-)-     O'',2.cos.(])  mean  anom. — ©  mean  anom.)  10 

-)-     0',2  .  .  . -)-     0»',2.cos.(  J)  mean  long. — ©  true  long. —  J)  mean  anom.)  11 

-)-     2M)  .  . . -)-     2'',0.cos.(2.  Dmeau  long. — 2.©  true  long. — 2. 3)  mean  anom.)  12 

-)-     0%4  ...-)-     O',4.cos.(2.mean  long,  of   3)  's  node — 2.©  true  long.)  13 

-)-l87',3  .  .  .  -)-187%7.cos.(  3)  corrected  anom.)                                                          '  I4 

-)-  10",0  .  .  . -j-   l0^0.cos.(2.3)corrected  anom.)  15 

-)-     0'',2  .  .  . -)-     O',3.cos.(3. 3) corrected  anom.)  IG 

-)-  26%0  ...-)-  2G^0.cos.(2. 3) corrected  long. — 2.©  true  long.)  17 

—  l',0  .  .  . —  P,0.cos.(  3) corrected  long. —  ©  true  long.)  IB 
-)-     0'%2  .  .  . -)-     O',2.cos.(3.corrected  long. — 3.©  true  long.)  19 

—  0%8  ...  —     O',8.cos.(2.  3)'s  true  distance  from  node  —  3)  corrected  anom.).  20 

To  obtain  the  moon^s  horizontal  parallax  for  any  latitude  :  Burg  supposes 
the  ellipticity  of  the  earth  to  be  -gi-^,  and  Mayer  uses  ■^^-^.  We  have 
supposed  it  to  be  -3!^,  in  conformity  with  the  calculations  in  the 
r.5604l  preceding  article  ;  and,  we  must  multiply  the  coefficients  of  the  table 
[5603,  or  5605],  by  unity,  jniniis  the  product  of  the  ellipticity  by  the 
square  of  the  sine  of  the  latitude  [1795"].  This  being  premised,  we 
have,    for    the    i^ioon's    equatorial  horizontal  parallax,    expressed  in  terms 


[5003] 


Vir.iv.  §26.]    COMPARISON  OF  THE  THEORY  WITH  OBSERVATION. 


66S 


depeiidiiis:    on     the    cosines    of    angles,    which  vary  in    piopoition  to   the 
longitude     v  ;* 


(Col.l.) 

Inequnlities 

(ledviCP'i  from 
tlio  tables  nf 
Mnsuii  ami  ATayer. 


(Col.  5.) 

Coefficients 
of  this 
theory. 


(Col.  3.) 

Excess  of  tlicso 
cnefficionts  over 
those  of  Muson'a 
tables. 


(Col.  4.) 

Excess  of  the 
coefficients  of 
Iîurg*rt  tables  over 
those  of  Mason. 


+3442%4 +3427',9   ....  —  I4',r)  ....  — 10',4  1 

+    1S3%5.cos.(ct— ^) +   1S7%7   ....  —  0%8   ....  —  0',4  2 

—  0^5.cos.(2ci'— 2:3) +       0',0  .  .  .  .   +  0V5  .  .  .  .  +  0',0  3 

—  O',3.cos.(3cr— 3w) +  0',0  4 

+       O',l.cos.(4cv— 4w) +  0'\0  5 

+     24%2.cos.(2v—2mv) +     24%7  .  .  .  .  +  0',5   .  .  .  .  +  0',0  6 

+     3S',i.cos.{2v—2mv—cv-\-zi) +     38%1    ....  —  0',3  .  .  .  .  +  0',0  7 

—  I',2.cos.(2y — 2mv-{-cv — -n).  .  . 

—  O',2.cos.(2» — 2mv-\-dmv — ct') 
+  r,7.cos.(2i'- 


■M' — c'mv-\^zi') -\- 


0%7   .  . 

■  •  + 

0',5   .  . 

••  + 

0%0     8 

0',2  .  . 

•  •  + 

0',0  .  . 

••  + 

0',0     9 

r,6  .  . 

. .  — 

0',1    .. 

••  + 

O^O  10 

0',3  .  . 

.  .  — 

0',0  .  . 

••  + 

0',0   11 

0',2  .  . 

. .  — 

0',1    .  . 

•■   + 

0',0  12 

Vfi  .  . 

.  .  — 

OM  .. 

••   + 

0',0   13 

O'fi  .  . 

. .  — 

0',3  .  . 

••  + 

0',0  14 

0',9   .  . 

•  •  + 

0',4  .  . 

••  + 

0',0   15 

3%6  .  . 

.  .  — 

0',3  .  . 

••  + 

0',0   16 

0*,2  .  . 

.  .  — 

0',G  .  . 

••   + 

0',0   17 

i%o.d- 

^i). . . 

.  .   + 

O'.O   18 

Tables  of 
the  moon's 
horizontal 
parallax 
reduced  to 
the  form 
of  the 
present 
theory. 


—  Q',3.cos.{c'mv—-:n') — 

—  O',l.cos.(2t) — 2mv — cv-\-c'mv-\--!s — «').  .  — 
-|-  I',7.cos.(2y — 2mv — cv — c'mv-}--!:s-\-ôi') .  .  -j-       l',6 

—  0%3.cos.(cv-\-c'mv — —t — -m') — 

-j-  O',5.cos.(cu — c^mv — ra-f-ra') -j- 

4-  o',9.cos.(2ct — 2v+2mv—2-a) + 

4-  O',4.cos.(2^« — 2v+2mv — 2&) — 

—  l',0.cos.(i' — mv) — 

—  0-,l  .cos.(4r— 4mv) _j_  0',0  19 

—  0",1.cos.(4î; — Amv — 2cv-\~2~,) -\-       0',0  .  .  .  .  -|-  O',  I    .  .  .  .  -|-  O'.O  20 

—  O',l.cos.(4v— 4mD— CT+ro) _       o^l    .  .  .  .  -f  0^0  .  .  .  .  -f  O'.O  21 

—  0',2.cos.(3cw — 2v-{-2mv — 3to) r     o'  0  22 

—  \',0.cos.{2gv—cv—2ê+zi) _       ]',o 4-   0%0  .  .  .  .  +  0',0  23 

+  0;2.cos.{2gv+cv—2ê~z,) ^  0',0  24 

—  O',2.cos.(cv—v+mv—:;j) _       o-,l.(l+;) 4-  0",0  25 

—  O',l.cos.(2ci'4-2y— 27WI' — 2:^) 4.       0',0  ....  4-  0',1    ....  4-  0',0  26 


[5605] 


(3082)     The  expression  of  the  parallax  [5331]  is,  for  a  latitude  whose  sine  is     \/^ 


[5606] 


664  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

The  equations  of  the  horizontal  parallax,  in  the  tables  of  Mayer,  Mason, 
and  Burg,  are  derived  from  Mayer's  theory,  and  we  see,  by  the  preceding 
table,  that  there  is  but  very  little  difference  between  the  coefficients  of  these 
equations,  and  those  of  the  preceding  analysis.  We  have,  however,  reason 
to  believe,  that  the  present  analysis  is  the  most  accurate,  since  this  theory 
represents,  better  than  Mayer's  does,  the  moon's  motion  in  longitude.  This 
is  however  a  mere  nicety  in  analysis  ;  because  observations  cannot  be  made, 
with  sufficient  accuracy,  to  determine  such  slight  differences.  With  respect 
to  tlie  constant  term  of  the  parallax,  it  was  determined  by  observation, 
both  by  Mayer  and  Burg.  This  last  astronomer  has  grounded  his  calculations 
chiefly  upon  a  very  great  number  of  Maskelyne's  observations,  and  he   has 

[5607]  found,  that  this  constant  part  is  less  than  in  Mayer's  tables,  by  10'',4.  We 
have  deduced  this  quantity,  in  [5330],  from  the  experiments  upon  the  length 
of  a  pendulum,  vibrating  in  a  second  ;  and  from  the  measures  of  the  degrees 
of  the  meridian  :  by  this  means,  we  have  found,  that  we    must   still   farther 

|.5608|  decrease, by  4',1  [56051inel],  the  constant  part  of  the  i)arallax  given  in  Burg's 
tables.  The  question  then  arises,  whether  this  difference  depends  on  the 
errors  of  the  observations,  or  on  those  of  the  elements  which  we  have  used 
in  the  calculation  ?  This  can  be  ascertained,  by  a  long  continued  series  of 
observations.  The  only  element  which  appears  to  be  liable  to  any  considerable 
degree  of  uncertainty,  is  the  moon's  mass.  We  have  seen,  in  [4628,4629'], 
that  to  make  the  result  of  the  theory  coincide  with  the  calculations  of  Burg, 

we  must  decrease  the    moon's    mass,  from    — -     to  — —  .     This  diminution 

58,6  74,2 

appears  rather  too  great,  to  accord  with  the  phenomena  of  the  tides,  with 
the  nutation  of  the  earth's  axis,  and  with  the  inequality  in  the  solar  tables. 


[5609] 


[5330,5310];  and,  by  supposing  the  oblateness  equal  to  -j^-g,  we  shall  obtain  the 
[5604a]     gquatorial  parallax,  by  multiplying  the  function  [5331], by     l+iX^ri^     nearly,  [1795"]  ; 

or  by  increasing  their  coefficients  ^l^  part.     This  process  being  applied  to  the  numbers  in 

[5331],  gives  those  in  [5605  col.  2],  corresponding  to  the  present  theory;  those  in 
[56046]     [SGOScol.  1],  being  deduced  from  [5603col.  2],  by  a  method  of  inversion   similar  to   that 

which  is  used  in  finding  [5575,  &ic.  col.  1],  from  [5551, fee.]. 


Vll.iv.  ^26.]     CO-AIPARISON  OF  THE  THEORY  WITH  OBSERVATION.  666 


which  depends  on  the  moon's  mass.  Upon  a  full  consideration  of  the  subject, 
it  appears  that  we  must  still  farther  diminish,  by  two  or  three  centesimal 
seconds,  the  constant  term  of  the  moon's  parallax,  as  it  is  given  by  Burg  ; 
who,  by  the  comparison  of  a  very  great  number  of  observations,  had  already 
diminished  the  constant  term,  adopted  by  other  astronomers,  and,  by 
that  means,  obtained  very  nearly  its  true  value. 


VOL.  III.  167 


[5610] 


666  THEORY  OF  THE  MOON;  [Méc  Cei. 


CHAPTER   V. 

ON  AN  INEQUALITY'  OF  A  LONG  PERIOD,  WHICH  APPEARS  TO  EXIST  IN  THE  MOON'S  MOTION. 

27.  We  have  remarked,  in  [4733 — 4736],  that  the  moon's  mean 
motion,  deduced  from  a  comparison  of  the  observations  of  Flamsteed  and 
Bradley,  is  sensibly  greater  than  that  which  results  from  the  observations  of 
[5611]  Bradley,  compared  with  those  of  Maskelyne  ;  moreover,  the  observations 
made  within  fifteen  or  twenty  years,  indicate,  in  this  motion,  a  still  greater 
diminution.  This  seems  to  prove,  that  there  is,  in  the  theory  of  the  moon's 
motion,  one  or  more  inequalities,  of  a  long  period  ;  and,  it  is  important 
to  ascertain  the  law  which  regulates  any  such  inequality.*     If  we  examine 

*  (3083)  The  propriety  of  introducing  an  inequality  of  this  kind,  into  tlie  lunar  theory, 
has  been  much  discussed  by  astronomers.     It  is  very  apparent,  that  the  theory  gives  such 

[5Glla]  an  inequality  ;  but,  the  result  of  the  latest  observations  leads  to  the  belief,  that  its 
coefficient  is  insensible  ;  and,  it  is  not  used  in  Damoiseau's  tables,  as  we  have  already 
observed   in   [4746a].      This  correction  was  proposed  by   D'Alembert,  about  sixty  years 

[56116]     3gQ^  ^Q  account  for  the  acceleration  of  the  moon's  motion  ;  before  La  Place  had  discovered 

the  real  cause  of  that  acceleration.      To  estimate  the   periods  of  the    arguments  of  the 

inequalities  treated  of  in  this  chapter,  we  have  taken,  from  the  third  edition  of  La  Lande's 

'^       astronomy;  the   following  mean  motions,  in  one  hundred  years  ;  supposing     nt,     n't,     to 

represent,  respectively,  the  mean  motions  of  the  moon  and  sun,  during  that  time. 

[5611d]  Motion  of  3) 's  perigee  =  (1—c). ni  =     4069'',2         [4817]; 

[56116]  _  Motion  of  5 's  node      =^  {\—g).nt  =—\9M\2         [4817]; 

[5611/]  Motion  of  ©'s  perigee  =  (l—f').n7=  1^7     [4817,4831]; 

[5611g-]  Precession  of  the  equinoxes  =  (/—I ).w<=  1^4     [5.347o,  4.3.59]. 

Hence  we  obtain  the  increments  of  the  arguments  of  the  first  members  of  the  following 


vil.  V.  §  27.] 


INEQUALITY  OF  A  LONG  PERIOD. 


667 


the  lunar  theory,  with  the  most  scrupulous  attention,  we  shall  find,  that  the 
action  of  the  planets  produces  nothing   of  this  kind.     This  is    made    quite      ^^^^'^^ 
evident,  by  the  analysis,  given  in  [5455 — 5539].     But,  the.  sunh  attraction    i',',T"'"^ 
produces,  in  the  expression  oj    nt-\-s,    an  inequality,  proportional  to  the  sine    ''"'*"'''"° 
of  the  following  angle  ,** 


3 1) — Qmv  +  'âc'mv — 2gv — ctJ4-2ti-f  si — 3; 


on  ilie 

sun's 

uciion. 


[56 J 3] 


expressions,  in  one  Inindi-ecl  years  ;  also,  the  times  of  the  periodical  revolutions  of  these 
arguments,    respectively,   or    the    number  of   years   requisite    to    complete    the    whole     [561U] 
circumference    .360''  ; 


Years 

3nt—<2gnt—ai(                       =  200'',8 

]79 

[.56 1 1.-] 

3nt—n't-^  c'n't—2gnt—cnt  =  igO^l 

181 

[56114] 

Zni—Zn't-^-'icnt-^gnt—cnt  =  195^7 

184 

[5611(1 

2fnt-\-nt-n't-\-cn't-2gni-cnt  =  20r',9 

178 

[5611m] 

3fnt—2g7it—cnt                       =  205'',0 

175 

[561  l7j] 

2  J)  node-f-  D  perigee 
2d  node-)-  D  perigee  —  @  perigee 
2  D  node  -f-  J>  perigee  —  3  ©  perigee 
2  J)  node-}- 3)  per.-©  per.-|-2.precession 
2  J>  node-)-  D  perigee  -)-  3. precession 

The  arguments  [56111,  m,n]  correspond,  respectively,  to  [5627,5633,5639].  The 
author  commenced  with  the  use  of  the  first  of  these  arguments,  as  in  [5665]  ;  but  he 
afterwards  proposed  to  change  it  into  the  form  [5611»].  Burckhardt  uses  the  argument 
23  node-f- D  perigee,  in  his  tables,  published  in  1812.  Several  papers  were  published  by 
LaPlace,  Burckhardt  and  Burg,  upon  this  subject,  in  the  Connaissance  des  Terns,  for  1813, 
1 823,  1 824,  Sic;  and  in  the  Monatliche  Correspondenz,  vols.  24, 26,  28  ;  also  by  Carlini  and 
Plana,  in  Zach's  Chrresyondance  Astronomique,  vol.  4,  page  26,  8ic.  La  Place  resumes 
the  subject  in  the  fifth  volume  of  this  work  [12755']  ;  but  does  not  there  speak  with  much 
confidence  relative  to  the  existence  of  this  inequality.  Finally,  he  omits  it  altoo-ether  in 
the  last  edition  of  his  Système  du  Monde,  which  was  published  a  short  time  before  his 
decease. 


[5611o] 

[5611;)] 
[56112] 


*  (3084)     As  an  example  of  the  production  of  such  quantities,  we  shall  observe   that 
the  function    \~r-)     [4809]  contains  the  term, 

15m'.  v!  4 

~  ~ë;:F~-s'"-(3''— 3i'')  ; 

and,  we  have,  in     u'^,     a  term  of  the  form, 

A. c'3.  cos. (3c'm D— 3zô')     [4838,&c.]  ; 
also,  in     xr"^,     a  term  of  the  form. 


[5613o] 
[56134] 


668  THEORY  OF  THE  MOON  ;  (Méc.CéJ. 


[5614] 


The  terms  which  compose  this  inequality  are  very  small,  in  the  differential 
equations  ;  but,  some  of  them  acquire,  by  successive  integrations,  the 
divisor  (3  —  3m-\-Sc'm—2g — c)^;  and  this  can  render  them  sensible, 
by  its  extreme  sniallness.  To  determine  this  divisor,  we  shall  observe,  that 
we  have,  by  using  the  values  [5117], 


3— 2o— c  =  0,00040849. 


[5615]  ^       -5 

[5616]      JMoreover, the  annual  motion  of  the  sun's  perigee  is  1P,949588  [42441inel]; 
hence  we  have,* 

[5617]  l—c'=- 0,00000922035. 

From  this  we  get, 
[5618]  s—3m+3c'm—2g—c  =  0,00040642  ; 

consequently,  we  have, 


A".ey^.cos.  {^gv-{-cv — 25 — ro)   ; 

which   is  similar  to  that   in  [4904  line  16].       The  product  of  these  two  term  gives,  by 

reduction, 

iA'  A".e'^.  ey^.cos.{Sc'mv—2gv—cv+2é-\-us-3-ui'). 

Multiplying  this  by  the  factor, 

[5613c]  ^.sin.(3i)— 3?;')  = ^  .  s\n.(3v—3mv),     nearly; 

r5613dl  and  reducing,  we  obtain  a  term  of  (-^\  depending  on  the  sine  of  the  angle  mentioned 
in  [5613] .  Substituting  this  in  [4753,  or  562U'],  we  find  that  it  will  suffer  two  integrations, 
which  will  introduce  the  divisor  [5614]. 

*  (3085)     The  motion  of  the  sun's  perigee  is     {l—c').n't     [5611/];  and,  if  we  put 
this  equal  to  ll',949588  [5616],  and  n't  =  1295977',349  [4077  line  3],  we  shall  get, 

[5616a]  (1— c').1295977',349=  ir,949588  ; 

whence,  we  easily  deduce  [5617].     Multiplying  this  by  3m  [51 17],  we  obtain, 

[56161]  3  m  — 3  f'w  =  0,00000207; 

subtracting  it  from   [56  J  5],   we  get   [5618];  whose  square  is  as  in  [5619].     We  have 
[5616c]    corrected  the  numbers  [5615,  5618,  5619],  for  a  small  mistake,  made  by  putting  [5615] 
equal  to  0,00040859. 


m   being  equal  to     —     [4835]  ;  but,  it  has  for  a  factor     3 — 2g — c,    which 

is  very  nearly  equal  to  3 — 3»i+3c'm — 2g — c  [5615,5618];  so  that  it 
must  be  considered  as  having  only  the  divisor  3 — Sm-\-Sc'm — 2^ — c,  which 
does  not  appear  to  be  small  enough  to  render  the  result  sensible.  If  the 
preceding   term    of   the  expression    of    R    depend    on  the  square    of   the 


[5620] 


VJI.  v.s^27.]  INEQUALITY  OF  A  LONG  PERIOD.  669 

(3— 3m+3c'm— 2j— f)'  =  0,0000001651 8.  [5619] 

We  have  seen,  however,  in  [4853',  &c.],  that  the  square  of  the  coefticicnt  of 

the  angle    v,    cannot  become  a  divisor  of  the  corresponding  inequality,  by 

means  of  the  successive  integrations,  when  we  notice  only  \.\\e  first  power  of     ^        ^ 

the   disturbing  force  ;     but    this   restriction    does    not  obtain   in   the   terms 

depending  on   the  .ignare  of  that   force  ;  and,   the  inequality  depending  on 

3v — 3mi'-{-3c'mv — 2gv — «)-j-2ii-t-s — 3:^',    can   arise   only   from    these    terms. 

To  prove  this,  we  shall  consider  the  term     3a.fJniJt.dR.,     of  the  expression     [5(320'] 

of    6v,     given  by  the  formula  [931].     This   term  appears  to  be  that  upon 

which  the  inequality  in  question  must  chiefly  depend.     The  development  of 

R    gives  some  terms  of  the  form,* 

R  =  H.cos.(3nt—3n't+3c'n't—2gnt-—cnt+2ê-^zi—3^').  [5621] 

If  these  terms  depend  only  on  the  first  power  of  the   disturbing   force,    n't 

and    c'n't    will  depend  on  the  sun's  co-ordinates  ;  and  then,  the  differential      [5622] 

dR,   which  only  affects  the  moon's  co-ordinates  [5363'],  will  become, 

dR  =  —(3—2g—c).ndt.H.sm.(37it—3n't+3c'n't—2gnt—cnt+2è+-.—3^').        ^5^33^ 

The  double  integral    3a.ffndt.dR    acquires  the  divisor, 

(S—3m+3c'm—2g—cf;  [5624] 


[5625] 


[5625'] 


*  (3086)     This  is  evident,  by  comparing  the  value  of  R    [949]  with  its  development     rsgai^-i 
[957,  &ic.].     It  also  appears,  by  a  process  similar  to  that  in  [5613rt — d],   from  which  we 
easily  perceive,  that     — ^,    or    R     [5360]  contains  a  term  of  the  form, 

iZ.cos.(3«— 37nt)+3c'mj;— 2^D— CT+2â-J-ra— 3ra').  [56216] 

Now,  substituting     nt     for     v,     and     mn  =  n'     [4835],  it  becomes   as  in  [5621].     Its     [5621c] 
differential,  relative  to     d,     supposing  it  not  to  affect     n't,     becomes  as  in  [5623]  ;    but, 
if  we  suppose  it  to  affect  the  part     — )ln't     of  the  term     — Znt,     and  put     n'z^mn,     as     [5621(/] 
above,  it  becomes  as  in  [56"26]. 

VOL.  III.  168 


670  THEORY  OF  THE  MOON;  [Mtc.  Cél. 

disturbing  force  ;   or,  in  other  words,  if  it  arise  from  the  substitution  of  the 

[5625"! 

parts  of  r,  v,  which  depend  on  the  first  power  of  that  force  ;  then,  the 
moon's  co-ordinates  will  contain  the  angles  n't  and  c'nt.  For  example, 
if  we  suppose,  that  the  part  — 2n7,  of  the  angle  — Sn't,  in  this  term 
of    R,     depends  on  the  moon's  co-ordinates  ;  we  shall  have, 

[5G2C]      djR  =  —{3—2m—2g—c).H.ndt.ûn.{Snt-Qn't^Scn't-'2.gnt-cnt^'2.'^-\-Tr>~S:,')  ; 

and,  the  term  3a.ffndt.dR  [5620']  gives,  in  the  expression  of  the 
moon's  longitude,  the  following  term, 

3a.(3—2m—'is:—c).n\H.sin.(3nt—3n't-\-Sc'nt—2<!nt—cnt-\-2ê-{-:z-3T^') 

[5G27]  oV  =    — ^ 7Z — 5 -^, ^ 7^ ; 

*•        ■'  (3 — 3m-{-3cm—2g — c)-'  ' 

which  may  become  sensible,  by  the  extreme  smallness  of  its  divisor.  The 
terms  of  this  kind,  are  very  numerous,  and  it  is  difficult  to  determine  all  of 
[5628]  them,  with  accuracy  ;  but  it  is  sufficient  for  the  present  purpose,  to  prove  the 
possibility  of  such  an  inequality  ;  since  we  may  then  refer  directly  to 
observations  to  determine  its  magnitude.  This  inequality  must  be  applied 
to  the  mean  motion,  and,  therefore,  also  to  the  mean  anomaly. 

The  theory  also  indicates  an  inequality,  depending  îipon  the  oblateness  of 
the  earth,  and  having  very  nearly  the  same  period  as  the  preceding  [5627]. 
We  have  seen,  in  [5340],  that  the  expression  of     Q     contains  the  term, 

Q=(la?  — ap).-.(,.^— X); 

now,  we  have,  as  in  [5344], 

ix  =  s.  cos.x4-\/i— «  -sin.x.  sin.fv  ; 
moreover,  we  have,  in  [4776], 


[5628'] 


[5629] 


[5630] 


[5631]  ^  —         u~' 

This  gives  in     R,     or  in     —  Q,     [5438],  the  function,^ 


*  (3087)     The  square   of    jx     [5630],  or  rather  the  square  of  the   last  term  of  that 
[5632a]     expression,   produces      {{-s^).sm.^'K.5m:fv  =  {\  —  s^).sm.^\.{\  —  \.cos.2fv);     so   that 
^fi   or    fJ-^  — ^   contains  the   term     — J(l— s^).sin.^X.cos.2/D  .     Substituting  this  in  [5629], 
we  obtain  in      Q ,     the  term, 


VII.v.§27.]  INEQUALITY  OF  A  LONG  PERIOD.  671 

R  =  —  Q^  (la?— ap).iD-.  «^  (1  — |s=).sin.2x.cos.2>  .  [5C32] 

Inequality 

This  function  produces,  by  its  development,  some  terms  depending  on  the        v , 

depending 

following  angle,*  ^'^^^^.n 

of  Ihe 

2fnt  -\-nt  —  n't  +  c'n't — "ignt  —  cyj<  +  2i)  +  ^  — 13' .  °'[  5633] 

They  are  analogous  to  those   produced  by   the  function     R     [5626, &c.], 
relative  to  the  sun's  action,  which  depends  on  the  angle  [5621], 

37it—Qn't+  3c' n't  — 2g7it~  cnt  +  2è-\-zi  —  3i^ .  [5634] 

The  coefficient  of  the  time     t ,     is   very   nearly  the    same    in  both   these      ^53351 
angles,  which  differ  from  each  other  about      1 80'',     in  the  present  situation 


q  =  — (Aap— ap)  .  |D3.  lL-£5  .  sin.2x.cos.2/i) .  [5632J] 

Now  the  expression  of    r     [5631]  gives, 

I  3  1 ^2 

—  ^u^.([J^s^)-^=u^.{l—§s^),     and     —^  =  u^.{l  —  ^s^),    nearly.  [^5632^] 

Substituting  this  in  the  preceding  value  of     Q,     it  gives  in     — Q,     or     R     [543S],  the 
term  [5632]. 

*  (3088)     This  angle  is   produced  by  the  development  of  the   term     m^.  4^.  cos.2/t) ,     fsessal 
which  occurs  in  [.5632].     For  the  value  of    s,     orratherof    s-\-Ss  ,     [4818,4896,4897] 
contains  the  terms, 

s  =  7'.sin.(^!> — ê)-\-Bf\  ey.s'm.(gv-\-cv — ê — w)  ;  [56335J 

whose  square  produces  the  term, 

2Bf\  ey^.sm.{gv — ê)  .sm.{gv-{-cv  —  6  —  ro)  ; 
or,  by  reduction, 

s^  =  —  Bf\  ey^.co5.{2gv^cv—2ê—^).  ^5^33^^ 

In  like  manner,  the  value  of    u,     or  that  of  «+'''*     [4826, 4904], contains   the  following 
terms, 

«  =  ^  •  J  l+'^o'"-  "^..e'.cos.iv  —  mv  +  c'mv  —  ^)  |  ;  ^5^33^ 

therefore,     11?    contains  the  term, 

^^»"'*  â'  •  ^  *  ^'"  ''°'*^''  ~  mv-\-c'mv  —  ^')  .  ^5g33^^ 


672  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

of  the  sun's  perigee.*     All  the  terms  of    R     [5632],  depend  entirely  upon 
the  co-ordinates  of  the  moon  ;t  so  that  if  we  represent  by, 

[5636]  R  =  iT.sin. (2/n^  +  nt  —  n't  +  c'n't  —  'Hgnt  —  cn^  -f  20  +  ^  —  ^')  , 

the  term  of  the  development  of  R  [5632],  which  depends  upon  the 
[5637]  preceding  angle  ;  we  shall  find,  that  this  term  acquires,  in  the  differential  àR, 
the  factor  (2/'+l — m-{-c'm — 2g — 1  ).n  ;  therefore,  it  will  have  for  a  divisor, 
in  the  double  integral  3a.Jfndt.dR,  only  the  ^^r^f  power,  and  not  the 
square  of  this  quantity  ;  hence,  it  is  evident,  that  this  term  must  be 
insensible. 

The  term  of  the  form     Y^^^,    which,  as  ive  have  seen  in  the  third  book,  may 
occur  in  the  expression  of  the  radius  of  the  earth,  can  also  introduce  into  the 


[5637'] 


Terra  of 

I'. 

depending 
on 


JMuhiplying  this,  by  the  term   of    s~     [5633c],  and  reducing,  we  get,  in     u^.s^,     a  terra 

of  the  following  form, 
[5633e]  2K'.cos.{v  —  mv-\-c'mv  —  2gv  —  cv-\-2è-{--a  —  ra'). 

Lastly,  multiplying   this    by     cos.2fv  ,     and   reducing,  we   obtain,   m     R,      a  term  of 

the  form, 
r5633/"l  ^ ■  ^°^' (^-^^ "f" ^  —  mv-\- c'mv  —  2gv  —  cv  -\-2è-^-a  —  ra')  . 

Now,  changing,  as  in  [5G21c],     v     into     nt ,     and   putting     ?)m  =  7i',     it  becomes   as 

in  [5633,5636]. 

*  (3089)  Subtracting  the  angle  [5634]  from  that  in  [5633],  we  get  for  their  difference, 
[5635a]  2.(/— 1)  .îi<-f  2.(1  —  c')  .?i'/+2ot'; 

and,  as  we  have,  very  nearly,  /=  1  ,  c'=  1  [53475',  5617],  the  preceding  expression 
[56356]     is,  very  nearly,  equal  to     2ra',     which  differs  but  little  from     180''     [4081, line  3],  as  in 

[5635]. 

f  (3090)     The  variable  quantities  which  occur  in     R     [5632],  are     ti^,    s",     cos.2fv  ; 

[5636o]     aZZ  of  which  refer  to  the  moon  ;  so  that  for  this  term  of    R,     the  differential     d/?  [5632] 

changes  into   the   complete  differential     dR  ;     and  by  taking  the  complete  differential  of 

[5636],  we  get, 

ggggj,     dR=  (2fn-^n—n'+c'n'--2gri—cn).(h.cos.{2fnt-]-nt—n't-\-c'7i't—2gnt—cnt-{-2ê-{-zi—'U!'). 

Substituting     Ji'  =  mn    [5621c]  in  the  factor  of  this  expression,  it  becomes, 
[5636c]  (2/+  1  —  m  +  cm  —  2g—c).ndt, 

corresponding  to  [5637]. 


VII.  V.  4-28.]  INEQUALITY  OF  A  LONG  PERIOD.  673 

expression  of  the  moon's  true  longitude,  an  inequality  depending  on* 

sin.  {Sfnt  —  2gn1  —  cnt  +  2  '  +  za)  ;  [5638'] 


[5fi39] 


which  is  now  nearly  confounded  with  the    two  preceding  ones  [5638/].     If 
this  inequality  become  sensible,  it  will  furnish  new  data  on  the  figure  of  the 
earth  ;  but  some  calculations,  which  I  have  made  for  this  object,  induce   me 
to  believe,  that  this  inequality,  like  the  former,  is  insensible.     The   lapse  of     [5639] 
ages,  and  new  improvements  in  analysis,  will  throw  light  on  this  delicate  and 
important  part  of  the  lunar  theory. 

28.     We  shall  now  proceed  to  establish  by  observations,  the  existence  of  the 
ineqxiality  depending  on  the  sine  of  the  angle, 

Snt  —  Sn't  +  Sc'n't  —  2gnt  —  cnt  +  2j  +  =i  —  3^'     [5627].  [5540] 


*  (3091)     In  the  same  manner  as  the  term     jj.^ — -j   of     F'-'    [1528c],  introduces  into 
V    [1811  or  5336],  the  term, 

C9 


[5636a] 


(lap  — ap)./xa.J/.  ^ 

„3 

tlie  term      1'^^'     [1811,   \52S(I],  produces  a  term,  whicii   contains   the   factor     —       or 
(x^.u^     [4776].     Now,  the  last  term  of    fA     [5630],  gives  in    (j.^     tlie  term, 

(1 — ««)^.  sin.^X  .sin.^/v  ,     or     sin.^X  .  sin.'/"w  ; 

which,  by  means  of  [2]  Int.  gives     — j  .  sin.^X  .  sin.3/y  .     Moreover,  the  complete  value     [56386] 
of    M     or     M-j-du     [4826,4904],  contains  terms  of  the  form, 

-  .  ^  l+A,.cos.{2gv-}-cv  —  2ê  —  zi)\;  [5638c] 

therefore,     u*     produces     4a~*.  ^, .  cos.(2^j;-l-c«  —  2è — zs)  .     Mukiplying  this   by   the 
term,     —  5  .  sin.^  X  .  sin.  3/u     [563Sè],  and  reducing  by  [18]  Int.  we  obtain, 

—  i.fr*.  A^.sm.^X.sm.{3fv  —  2gv  —  cv  -|-2â+ra)  ;  [5C38rf] 

which,   by  changing     v      into      nt,      produces  the   angle   mentioned   in    [5638'].     The 
difierence  between  this  angle  [5638'],  and  that  in  [5626],  is  represented  by, 

3.(/— 1).«^— 3.(c'— l).n'<  +  3ra';  [5638e] 

which,  by  reason  of  the  smallness  of  / —  1 ,    <f —  1   [5635i],  is  now  nearly  equal  to     3t^'  ; 
and  as  this  varies  slowly,  the  periods  of  the  inequalities  [5627,  5638'],  are  nearly  equal  to     [5638/"] 
each  other,  and  to  that  in  [5633],  as  in  [56356,5630],  or  in  [5611/,ot,  n]. 

VOL.  III.  169 


674  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

If  we  represent  this  angle  bj     E,     we  shall  evidently  have, 

[5641]  E  =  2.1ong.Dnode  + long.  3  perigee  —  o.long.©  perigee      [5611/]  ; 

and  we  shall  now  proceed  to  show,  that  the  law  of  the  variations  of  sin.jE, 
is  the  same  as  that  of  the  variations  which  have  been  observed  in  the  moon's 
mean  motion. 

In  the  lunar  tables,  inserted  in  the  third  edition  of  La  Lande's  astronomy,  it 

is  supposed,  that  in  the  interval  of  100  Julian  years,  the  moon's  motion  relative 

[5642]     to  the  equinoxes,  exceeds  a  whole  number  of  circumferences,  by  307'' ôS™  12',- 

[5643]     and  that  the  epoch  of  1750  is  IBS'*  17"'14',6.     The  correction  of  the  epoch 

of  these  tables,  in  1691,  has  been  determined   by  Bouvard  and  Burg;   by 

means  of  more  than  two  hundred  observations  of  La  Hire  and  Flamsteed  ; 

[5644]     they  have  both  found  this  correction  equal  to     — 4',4. 

The  correction  of  the  epoch  of  the  same  tables,  in  1756,  has  been 
determined  by  Mason  and  Bouvard,  by  means  of  a  very  great  number  of 

[5644']  Bradley's  observations  ;  and  they  have  found  it  to  be  0%0.  Thus,  in  the 
interval  from  1691  to  1756,  the  moon's  mean  motion  was  greater  than  the 

[5645]  tables,  by  4',4  ,  which  gives  6',8*  for  the  increment  of  the  mean  motion 
of  the  same  tables  in  a  century. 

Burg  has  found,  by  a  great  number  of  Maskelyne's  observations,  that  the 
correction  of  the  epoch  of  these  tables  is  equal  to     — 3',0,     in   1766,  and 
[5646]     — 9',1,    in  1779. 

Bouvard    has  found,  by  a  great  number   of  Maskelyne's  observations, 
[5647]     — 17',6,    for  the  correction  of  the  epoch  of  these  tables,  in  1789. 

Lastly,  by  a  considerable  number   of  observations   made   at  Greenwich, 
Paris  and  Gotha,  it  has  been  found,  that  the  correction  of  the  epochs  of  the 
[5648]     same  tables,  in  1801,  is    — 28',5. 


[5648'] 


Hence  it  appears,  that,  from  1756  to  1801,  the  moon's  mean  motion  has 
decreased  in  a  sensible  manner  ;  and,  that  this  diminution  is  now  increasing. 


*  (3092)     In  the  interval  from  1691  to  1756,  which  is  65  years,  this  correction  varies 
[5645a]    ^,4     [5645],  which  is  at  the  rate  of   6',8    in  a  century,  as  in  [5645]. 


VII.v.§28.]  INEQUALITY  OF  A  LONG  PERIOD  675 

For,  in  the  interval  between  1756  and  1779,  which  is  twenty-three  years, 

this  motion  was  less  than  by  the  tables,  by    9',1     [5644', 5646]  ;  and,  from      [5649] 

1779  to   1801,   that   is,  in   twenty-two  years,  it  was  less  by    19,4.*     The 

epoch  of  1756,  compared  with  that  of  1779,  gives    39',5,t    for  the  decrease      [5650] 

of  the  tabular  motion  in  a  century;  whilst  the   epoch  from  1756   to   1801 

gives     63',3,     for  this  diminution.     Therefore,  the  combination  of  all  these      [5651] 

observations  evidently  indicates  the  three  following  results.     First.  A  mean 

motion  greater  than  that  of  the  tables,  from  1691  to  1756  [5644'].     Second. 

A  less  mean  motion   from    1756    to   the    present  time  [5651].      Third.   A 

diminution  which  becomes  more  and  more  rapid. 


[5652] 


These  results  are  conformable  to  the  march  of  the  preceding  inequality. 
For,  at  the  epoch  of  1691,  the  sine  of    E    was   negative;!  and,   it  was      [5053] 
positive  in  1756  ;  therefore,  this  inequality  increases  the  moon's  mean  motion, 
in  that  interval.  In  1756,  this  sine  was  positive,  and  near  its  maximum;  and      [5654] 
since  that  epoch,  it  has  always  been  decreasing  ;    therefore,  the  inequality 
decreases  the    moon's  mean   motion.     Lastly,  this  sine  was  nearly  equal  to 

*  (309.3)     This  is  the  difference  of  tlie  two  corrections  — 9%\,  — 28*',5  [5646,5648].      [5648a] 

t  (3094)  The  difference  of  the  numbers  0',0,  — 9',1  [5644',  5646]  is  O',!, 
corresponding  to  the  Interval  1779 — 1756:=  23  years.  This  is  at  the  rate  of  39',5,  in  [5(550o] 
100  years;  as  in  [5650].  If,  instead  of  — 9',1,  we  had  used  — 28',5  [5648], 
corresponding  to  1801,  the  variation  would  be  28',5,  in  45  years  ;  corresponding  to 
63',3,  in  a  century.  These  differ  a  httle  from  the  results  of  the  author  in  the  original  [56506] 
work;  who  gives  126"=40',8,  and  172",5  =  55',9,  instead  of  39^5  and  63V3, 
respectively. 

J  (3095)     According  to  the  tables  in  La  Lande's  astronomy,  the  values  of  E,    at  the 
different  epochs,  are  nearly  as  follows  ; 

Years,         1691  1750  1756  1801  [5652a] 

Values  of  E,         320''  76"  87"  176".  [56526] 

The  signs  of  the  angles  change  from  negative  to  positive,  in  1750,  &£c.,  as  in  [5653.  &c.]  ;     [5652c1 
and,  in  1756,    ûn.E    attains   nearly  its    maximum  value,  or    sin. 90".     Moreover,  if  we 
represent,  as  in   [5658],  by    y.s'm.E,    the   part  of  this  correction  which  depends  on    E,     [565iid] 
and  suppose    E    to  increase  by  the  quantity  dE,  the  corresponding  increment  of  y. sin. JÏ 
becomes    y.<Z£.cos.E;  which  has,  evidently,  its  greatest  negative  value  when    E  ^  180'',     [5652c] 
or  sin.£  ^  0  ;  as  in  [5654'J  • 


676  THEORY  OF  THE  MOON  ;  [Méc.  Cél 

[5654'] 


nothing,  in  1801  [56526];  and  then,  the  diminution  of  the  mean  motion 
was  the  greatest  [5652e].  The  decrement  of  the  mean  motion  must, 
therefore,  be  greatest  about  the  year  last  mentioned. 


We  shall  now  determine  the  coefficient  of  this  inequality.  It  is  evident, 
that  it  must  produce  a  change,  both  in  the  epoch  of  the  tables  in   1750,  and 

[5655]  in  the  mean  motion  of  the  tables  in  a  hundred  years.  We  shall  put  s 
for  the  correction  of  the  epoch  of  the  tables  in  1750;  x  for  the  diminution 

[5656]  Q^  ^j^p  mean  motion  in  a  century  :  and,  y  for  the  coefficient  of  the 
preceding  inequality.  The  formula  for  the  correction  of  the  epochs  of 
the  tables,  will  be,  by  putting  i  for  the  number  of  centuries  elapsed 
since  1750, 


[5657] 


[5658]  -  X  .i  -\-  y .  Sin.£.  [Correction  of  the  epoch] 

To    determine   the    three  unknown   quantities    s,     x     and     y  ;     we    have 
[5658']     compared   this  formula  with  the  results  of  observation,  at  the  three  epochs 
1691,   1756    and    1801  ;     and,    by  this    means,    have    obtained    the  three 
following  equations  ;* 

s+x.0,59— 3/.0,63660  =— 4',4  ; 
[5659]  £— .T.0,06+î/.0,99898  =     0',0  ; 

£—a;.0,51 +^.0,08199  =-28^5. 

These  three  equations  give, 


[Year  1691] 

1 

[Year  1756] 

2 

[Year  1801] 

3 

*  (-3096)  The  coefficients  of  v,  in  the  equation  [5658,  or  5659],  are  represented  by 
[5659al  Tffff-(1^'50  —  years);  those  of  y  are  the  values  of  sm.E,  corresponding  to  the 
respective  years  ;  similar  to  those  in  [56526],  but  taken  to  a  greater  degree  of  accuracy. 
Lastly,  the  constant  terms  of  the  second  members,  are  the  quantities  computed  in 
[5644,5644',  5648].  The  equations  [5659]  give  the  values  of  s,  x,  y  [5660];  as 
we  can  easily  prove,  by  substituting  them  In  [5659].  With  these  values,  we  find,  that  the 
formula  [5658]  becomes, 


[56596] 


[5659c]  —  J3',46  — 31^96.^■+15•,39.sin.i:  ; 

from  this  we  obtain  the  values  [5661],  using  the  values  of  E,  corresponding  to  the 
different  epochs.  We  may  observe,  that  the  quantities  — '^'fi,  — 9',1,  — 17',6 
[5646,  5647]  furnish  three  additional  equations,  of  the  form  [5659]  ;  and,  we  can 
determine  the  value  of  s,  x,  y,  by  combining  all  these  equations,  by  the  method  of 
the  least  squares  [815e — /]. 


vil.  V.  §  23.] 


INEQUALITY  OF  A  LONG  PERIOD. 


677 


£  =— 13^46  ; 
.T  =  31  ,96  ; 
y=      15%39  . 


1 

2       [5660] 


3 


By  means  of  these  values,  we  find  — 4',4  ,  +  ()',0  ,  — 3',8  ,  — ll',3, 
— 18%7  ,  and  — 28',5  ,  for  the  corrections  of  the  six  epochs  of  1691, 
1756, 1766, 1779,  1789,  1801.  The  sum  of  these  six  corrections  is  —66,7; 
and  the  sum  of  the  six  corrections  determined  by  observations  is  —  62',6  ; 
the  whole  of  these  corrections  taken  together,  indicate,  therefore,  that  we 
must  increase  the  preceding  value  of  s  by  0',7  ;*  and  then  the  formula 
for  correcting  the  tables  becomes, 

—  i2',8  -  31%96  .  i  +  15S39  .  sin.E  . 

Calculating  by  this  formula,  the  corrections  for  the  six  epochs,  we  have. 


(Col.  1.)  (Col.  2.) 

Corrections  of  the  tables 
by  observations. 

—    4',4     [5644] 


(Col.  3.) 

Corrrctions  by  the 
formula. 


(Col.  4.) 

Excess  of  llipse  corrections 
above  tlio  first. 


1691 
1756 
1766 
1779 
1789 
1801 


—    3',7 


+  0^7     1 


+     0',0  [5644'] +    0',7 +  0',7  2 

—  3',0  [5646] -    3',1 _  0,1  3 

—  9',1  [5646] —  10',6 —  P,5  4 

—  17',6  [5647] —  18',0 —  0',4  5 

—  28%5  [5648] —  27%8 +  0',7  6 

The  difference  between  the  results  of  observation  and  those  of  the  formula, 
are  within  the  limits  of  the  errors  to  which  these  last  results  are  liable  ;  they 
may  in  part  depend  on  the  formula  itself,  which  can  be  rectified  by  new 
observations. 


[5661] 

[5662] 
[5663] 

[5664] 
[5665] 


[5666] 


*  (3097)  If  we  suppose  the  expression  f  [5G58],  to  be  increased  by  the  quantity 
e',  it  will  augment  each  of  the  six  numbers  [5661],  by  the  same  quantity  ^,  [5665a] 
and  the  sum  of  all  of  them  will  become  —  66',7-(-6£'.  Putting  this  equal  to  the 
sum  —  62',6  of  the  corrections  by  observation,  as  they  are  given  in  the  second  column 
of  the  table  [5666],  we  get  —  66',7-j-6e' =  —  62',6  ;  whence  e'=0',7;  as  in 
[5664].  Adding  this  to  each  of  the  values  [5661],  we  get  the  numbers  in  the  third 
column  of  [5666].  Subtracting  the  terms  in  the  second  column  of  this  table,  from  those  in 
the  third,  we  get  the  corrections  in  the  fourth  column. 

VOL.  III.  170 


[56656] 


[5665c] 


678 


THEORY  OF  THE  MOON  ; 


[Mec.  Cel 


CHAPTER    VI. 


ON  THE  SECULAR  VARIATIONS  OF  THE  MOTIONS  OF  THE  MOON  ANU  EARTH,  WHICH  CAN  BE  PRODUCED 
BY  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID  SURROUNDING  THE  SUN. 


29.     It  is  possible,  that  there  may  be  an  extremely  rare  fluid  surrounding 
[5666]      the   sun,  which   alters  the  motions  of   the  planets   and  satellites  ;*   it  is, 
therefore,  interesting  to  know  its  influence  on  the  motions  of  the  moon  and 
earth.     To  determine  it,  we  shall  put, 

[5667]      X  J  111  ^1  for  the  rectangular  co-ordinates  of  the  moon,  referred  to  the  centre 
of  gravity  of  the  earth  ; 

[5668]      ^'t  y'l  ~i  for  the  rectangular  co-cordinates  of  the  earth,  referred  to  the  sun's 
centre. 

The  moon's  absolute  velocity   about  the    sun,   will   be   expressed  by    the 
following  function  ;t 


[5667a] 
[56676] 
[5667c] 

[5669a] 


*  (3098)  The  existenceof  sucha  resisting  medium  is  now  considered  as  highly  probable, 
in  consequence  of  the  observed  decrease  of  the  times  of  revolution  of  Encke's  comet,  in  its 
successire  appearances  between  the  years  17S6  and  1829.  Encke  has  given  an  important 
paper  on  this  subject,  in  the  ninth  volume  of  Schumacher's  Astronomische  Nachrichten, 
pag.  .317 — 348  ;  to  which  we  may  have  occasion  to  refer,  in  treating  of  the  perturbations 
of  comets.  We  shall  here  merely  remark,  that  the  extreme  rarity  of  the  mass  of  this 
comet,  makes  it  peculiarly  well  adapted  to  the  discovery  of  the  effects  of  such  a  resisting 
ethereal  fluid  ;  which  cannot,  however,  produce  any  sensible  effect  on  the  large  and  dense 
bodies  of  the  planets  and  satellites. 

t  (3099)  The  rectangular  co-ordinates  of  the  moon,  referred  to  the  sun's  centre, 
are  represented  by  x-{-x' ,  y-\-y',  ~-|-~',  as  in  [5667,5668].  Their  differentials, 
divided  by     dt,     are, 


VII.vi.§29.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        679 


v_K — -r     J  ^  \  :f  T   yj  -r\ 1 j__ ^   j^j^g  moon's  velocity. 

JVe  shall  suppose,  that  the  resistance  which  the  moon  suffers,  is  represented  by 
the  product  of  the  square  of  the  velocity  by  a  coefficient    K,    depending  upon      ^    '  ^ 
the  density  of  the  ether,  and  upon  the  surface  and  density  of  the  moon.     If   "rule""" 
we  resolve  it,  in  directions  parallel  to  the  axes     x,     y,     z,   we  shall  obtain    "[^j^'» 
the  three  following  forces  •* 


K.(dx'+dx)      , 

^^2 — •  V{dx'+dxy+{dy'+dyy+{dz'+dzf;         [f»™  p'-iwi  lo  x]    1 


[5671] 


■  ^H^i--^  •    K/{dx'+dxf+{dy'-^dyf+{dz'+dzy  ■  [fo™  I-alle:  ,„  ,]       2       Exprès- 


sions 
of  the 
resistance 
of  the 


K.idz'A-dz')  , ofth, 

^—r^'-\/{d3i^rdxfA-{d\j-^dyf-\-{dz'-Ydzf,  [Force  parallel  ,o  :1       3      moon 


di 


In  the  lunar  theory,  the  earth  is  supposed  to  be  at  rest  ;  we  must,  therefore, 
apply  to  the  moon,  in  a  contrary  direction,   the   resistance  which  the   earth     [5671' 
suffers.     This  resistance  being   resolved,  in  directions  parallel  to  the  same 


dx+dx'  dy+dy'  dz-\-dz' 

-W~    '  dt        '  dt        '  [5669i] 

which  evidently  represent  the  velocity  of  the  moon  about  the  sun,  resolved  in  directions 
parallel  to  the  axes     x,     y,     z.     The  square  root  of  the  sum  of  the  squares  of  the  three     [5669c] 
partial  velocities  [5669è],  gives  the  whole  velocity  [5669]  ;  as  is  evident  from  [40a b]. 

*  (3100)     Putting,  for  brevity, 

d^^  =  y/(dx'+dxr+{dy'+dyr+{dz'+dz)%  ^5671  a] 

we  find,  that   the  absolute  velocity  of  the  moon  is     -—       [5669]    ;     consequently,     the 

resistance  is     — ^-^JI^      [^6*0],    in     the     direction    of    the    described    arc     fAv.     The 

[56716] 
negative  sign  being    prefixed,  because    the    resistance  tends    to  decrease  tliis  arc.     To 

resolve  this  force,  in  directions  parallel  to   the  axes  x,     y,     z,     we   must  multiply  it 

by  the  expressions, 

dx'-\-dx  dy'+dy  dx'-\-dz 

~d^    '  IbT    '  ~d^    '  [5671c] 

respectively  ;  as  is  apparent  fi-om  [40J].     Hence  we  obtain  the  expressions  [5671]. 


Ç80  THEORY  OF  THE  MOON  ;  fMéc.Cél. 

axes,  gives  the  three  following  forces.* 


dx' 

earth.  df 


fr,ir"  —  K'.  % .  s/dx-^+dy^+dz'^\  1 


[5672]  -  K-  %  .  ^da^^+dr+d-^  ;  2 

—  K'.  ^, .  v/rf^"-^+rf2/'^+^^'^  ;  ^ 

^'  6ez/?^  a  coefficient,  ivhich  differs  from  K,  and  depends  iipon  the 
resistance  ivhich  the  earth  suffers.  Now  having  represented  the  forces,  which 
act  upon  the  moon,  parallel  to  the  axes  of    x ,     y,     and     z  ,     by, 

m'  (f)'  a-  ^''''^"•^' 

we  shall  have,  by  noticing  only  the  preceding  forces, 

'^^^  =  K'.  Jl  .  ^dx'^+dy'^+dz'^'  1 


Relative 
forces  00 
the  moon, 
considered 
as  moving 


^  •  ^^  •  K^WTWTWTW+W+W;  2 


ÏSàï""  C^)  =K'X.  ^dx'^+dy'^+d^^  3 


real. 


dy  J  di^ 

—  K  .  —^ .  \/{dx'+di:f+{dy'+dy)--j-{dz-{.dzy, 

—  K.  ^^—   •  \/{dx'+dxf+{dy'+dyf+dz'+dzf 


6 


[5673a] 


*  (3101)  The  resistances  [5671]  corresponding  to  tiie  moon,  will  evidently  give  those 
relative  to  the  earth,  by  taking  the  co-ordinates,  so  as  to  correspond  to  the  earth,  and  changing 
the  factor  K  into  K .  This  requires  that  we  should  put  a?==0,  y  =  0  ,  s  =  0; 
in  [5671].  Hence  we  obtain  the  forces  relative  to  the  earth,  as  in  [5672].  The  signs  of 
[56736]  the  forces  [5672],  must  be  changed,  as  in  [5671'],  and  then  they  must  be  added  to  the 
corresponding  quantities  in  [5671],  to  obtain  the  forces  of  resistance  of  the  ether,  supposing 
the  moon  to  revolve  about  the  earth  considered  as  at  rest.     These  forces  are  represented,  in 

„„       [498n'— 499a],  by  (— ^  j ,  (-j^)  >  (-i^j  5  hence,  we  easily  obtain  the  expressions  [5673]. 


VII.  vi.  ^-29.]  EFFECT  OF  THE  RESISTAACE  OF  AN  ETHEREAL  FLUID.        681 
Now  we  have,  by  supposing  the  moon's  co-ordinates  only  to  be  variable, 

If  we  substitute  the  values, 

COS. y  sin.i'  s 

^-  -^-^      z/  =  —  ;       --  =  -  ;  [5674'] 

which  are  given  in  [4777 — 4779],  we  shall  obtain,* 

'^«--S-l— (^?)+'>"-(f)+»-(f)l       > 

dv    c    .         fdQ\  fdq\  ) 
.{  sm.  V  .  [  -^]  —  COS.  V  .[-^\}  2 

M         I 


u       \  dz. 
Then  we  have,t 


drj  \dyj  )  [5675] 


'"2-(S)-*'+(t?)-*"  +  (t?)-''- 


*  (3102)     The  expressions  of     Q     [4756,  5673],  may  be   considered   as   functions  of 
X,     y,     r.     x',     y',     z' ;     but  if  ue  suppose  the  moon's  co-ordinates     x,     y,     z,     io    ^        "J 
be  t!ie  onlv  variable  quantities,  we  shall  get  for     t/Q     the   expression    [5674].     Now,  the 
differentials  of    x,     y,     z     [5674']  give, 

— dv.sm.v        du.cos.v                    dv.cos.v         dus'm.v                     ds       sdu 
dx  == 5 —  ;      dy  = -—  ;      dz  = -.  [56756] 

Substituting  these  in  [5674],  and  connecting  the  terms  depending  on     du,     dv ,     ds  ,     we 
get  [5675]. 


[5676a] 


f  (3103)  Considering  the  co-ordinates  of  the  moon  as  the  only  variable  quanthies,  we 
shall  have  the  two  expressions  of  d(^  [5674,  5676].  In  the  first  of  these  expressions, 
the  moon's  co-ordinates  are  x ,  y ,  z ,  and  in  the  second  u ,  v ,  s;  and  if  we 
substitute,  in  the  first,  the  values  of  dx,  dy,  dz  [5675i],  it  becomes  equal  to  the  second, 
and,  by  this  substitution,  produces  the  function  [5675].  Hence  it  evidently  follows,  that  [56766] 
the  expressions  [5675,5676]  must  be  equivalent.  Now,  by  comparing  together  the  coefficients 
of  f7«,    dv  ,    ds,    in  these  two  last  expressions  of  t/Q,  we  get  the  equations  [5677 — 5679]. 

Multiplying  [5677],  by     — 1,     and   [5679],   by     — -;     then,  taking  the    sum    of   the      [5676c] 

two  products,  we  get  [5680]. 

VOL.  III.  171 


682  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

and,  by  comparing  these  two  values  of     Q  ,     we  shall  obtain, 


[5679] 


\  ch   )  M         V  f'-2 


Hence  we  deduce, 

'-»>  -  (f  )  -  :  •  (f)  -  i  ■  1  --  ■  (f  ) + ^'"■"  ■  (f  )  I  [«'='«']■ 

Now  we  have,  as  in  [4777/ — /t], 

,.„„                                                       cos.d'                 ,         sin.v'  ,         s' 

[5681]  -P'  ^  — ^  ;  ^'  =  ;  .^  =  -  ; 

v'  denoting  the  longiiitile  of  the  earth  seen  from  the  sun.     If  we  take  for  a 
[5682]     fixed  plane,  that  of  the  ecliptic   in  1750,  we  may   suppose     5'  =  0 .     We 
shall  represent  by     r'dq',     the   small  arc  which  is  described  by  the  earth 
in  the  time     dt ,     and  we  shall  have, 

[5683]  ^(dx'^  +  df  +  dz'^)  =  î'dq'     [40«,  &c.  ] . 

This  arc  is  to  that  which  is  described  by  the   moon,   in   its   relative  motion 

[5684]     about  the  earth,  very  nearly  in  the  ratio  of*   —     to     1;     therefore,  it  is  at 

[5484']    least,  thirty  times  as  great  ;  and  we  shall  have,  very  nearly,! 


*  (3104)     Whilst  the  moon  describes  the  angle     dv  .     with   the    radius     a,     the   sun 

[5684a]    ^Jgg(.^.^^3es    f^e    angle     mdv  ,     with    the    radius     a',     nearly  ;  as   is  evident  from    [4837], 

[4838,  &;c.  ]  ;    so    that    the    space    described    by    the   moon    is     adv ,     and    the    space 

described  by  the  sun     a'mdv  ,     nearly.      The    ratio   of  the  second   of  these  expressions, 
[56846]  •'  , 

to   the  first,   is  denoted  by     —,     as  in  [5G84].     Substituting     -  =  400,    ?«  =  0,0748. 
[5684c]  '  '        a  a 

[5221,  5117],  it  becomes  nearly  equal  to     30,     as  in  [56S4']. 

f   (3105)     Developing  the  terms  in  the  first  member  of  [5085],  and   substituting     r'dfj' 

[5683],  it  becomes, 

^\r'Mq'^+2dx'dx-\-2dy'dy-\-2dz'dz+dx^+dy^-+dz^l 
[5685a]  ^ 


VII.vi429.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        683 


If  we  neglect  the  excentricity  of  the  earth's  orbit,  we  shall  have  dq'  =  mdt; 
the  time  t  being  represented  by  the  moon's  mean  motion.  Then  we 
have,* 


[5686] 


'^^■'         —sin.!)';  ^  =  cos.îJ';  [5687] 


r  dq'  r'  dq 


consequently, 

\/{dx'-{-  dxY  +  (rf!/4-  dyf  +  (rfz'+  dzf  =  ma',  dt—dx.sin.v'+dy.cos.v'. 
Hence,  we  easilv  obtain, t 


[5688] 


Putting  now     s  =  0     [5682],  we  have     z' =  0     [5681]  ;  substituting  this,  and  neglecting     [5685J] 
also     di^-^dy~-{-dz^,     in  comparison  with  the  other  terms,  we  easily  reduce  it  to  the  form 
in  the  second  member  of  [5685]. 

*  (3106)     Neglecting  the  excentricity  of  the  earth's   orbit,  we  may  put     7-'  =  a'=-     [5687o] 

[4 937n],  and  the  described  arc  [5683]  becomes     r' dq  =  a' dv' ;     moreover,  the  values  of 

x',     y'     [5681],     become     x'  =  a  .  cos.i)',      y' =  a'.i'm.v'  ;     whose    differentials    are     *•  ■' 

dx' =  — ddv'.  sin  v',       dy'=  a'dv'.  cos.  v'.       Dividing   these   by   the    above    expression 

r'dq'  =  adv',     we  obtain  the  values  [5687]  ;  substituting  these,  and     dq':=mdt  [5686], 

in  [5685],  we  get  [-5688].     The  expressions  [5683,  5688]   may  be  put  under  the  forms 

[56S7e,_/'],  bv  merely  changing,  as  above,    r'     into     —,     and     do',     or     dv'    into    mdt. 

•  '  ^    =^  "'  ■'  [5687rf] 

Lastly,  the  expressions  of    r'dq',     dx',     dy'    [56876,  c],   may  be   put  under  the   forms 
[5687^],  which  will  be  of  use  hereafter  ; 

, mdt 

Sj  dx'"-  -f-  dy'  9  +  J~'  2  =    -^    ;  [5687e] 

, mdt       7      .       ,      , 

v/(rfi'+rfz)2+(rfy'+f/y)a+(rf~'4-^s)2  =:  — — (/a:.sin.i/+f??/.cos.i'';  [5687/] 

r'dd=—-  dx'=—'^^—-  ..^rndt^^^  [5687^^ 

u  u'        '  ^  ?/ 

t  (3107)     Multiplying    [5687e]  by  the  value   of    ^^  [5687§-],  we  get  [5687A]; 


684  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

/rfQ\         -(K'-K).m^.^m.v'        3K.m  dx    ,    Km   dx  ^   ,  ,    Km  dy     .     ^  , 

\dy  J  m'2  2m'      t^i     '     2it'   d^  2?<'   (//  ' 


[5691] 


m 


Km  dz 

u    '  dt 


Kdx  Kdx 

again,  multiplying  [5687/]  successively  by =-g— ,     —        -,     and  neglecting,  in  the 

last  product,  the  terms  of  the  order     dx  .  dy,    we  gel  [5687i,À:]  ; 


dx' ,  K'. 


[5687A]  K'.  -j^^.^-dx'^J^dy"^+dz' 


m^.sin.v' 


rf<2  V  "         I      y      I  „/2 


1 


[5687i] 


r-r   dx      , ^ -K?n-.  sin.t)'        Km  dx    ,    ^  , 

-K.  -.^[dx'+dxf+{dy'+dyf+{dz'+dzf=—^^ —  -rf,-""-  " 

H Y  .—■  .sm.y  .COS.  i; 

u'     dt 


[5687/fc]     -^^-  -^,V{^'^'^'+<^^f+W+c'yr+{dz'+dz)^  =  —Vit- 

Adding  together  the   expressions  [5687/*,?',^"],  we   find,  that  the  first  member  of  the  sum 

L         J      becomes  the  same  as  the  expression  of    f'T"  )     [5673  lines  1,2];    and  the  second  member 

r5687   1    °^  ^'^'^  ^""^  '^  easily  reduced  to  the  form  [5689],  by  substituting    sin.^j;'  =;  A— i.cos.2y', 
sin.i;'.cos.j;'=  |.sin.2«',    and  making  a  slight  reduction. 

We  may  obtain  [5690],  from  [5673  lines  3,4],  by  a  similar  process  ;  or,  we  may  find 
it  more  readily  by  derivation.      For,  if  we  change,  reciprocally,  x    into   y,     and     x'    into 

[5687n]    y''    we  shall  find,  that     f^\     [5673  lines  1,  2]  changes  into     (^-^^     [5673  lines  3,  4]. 

Now,  this  change  in  the  values  of    o',     y',     is  made  by  putting    sin.i)'    for    cos.?)',     and 

cos.t)'  for  sin.î)',  in  [5681].  This  does  not  alter  the  value  of  sin.i;'. cos. 1/=  J. sin.  2i)' 
[5687o]     [5687i],   but  it   changes    sin.^u'    [5687i]  into     cos.V=:^+à-cos.2w';     so  that  we  must 

ç(rrite  +J.cos.2i>',  instead  of  — J.cos.2t)',  in  [5687?«].  Hence  it  appears,  that  we  may 
[5687p]     Q^jj^ij,  [5690]  from   [5689],   by  writing   dx   for  dy,   reciprocally,  also    cos.d'  for    sin.v', 

and  changing  the  sign  of    cos.2v'. 

Lastly,  if  we  substitute     ~'=  0     [5685Zi],  in  [5673  lines  5,6],  we   find,  that  the  term 

1 5687g]     in  [5673  line  5]  vanishes,  and  the  factor  of  the  radical  in  [5673  line  6]  becomes    —  -^  ■  ^i" 

Multiplying  this  by  the  value  of  the  radical  [56S7/],  and  neglecting  terms  of  the  second 
[5687r]     p^^,.g,.i^     j^^     jy^     J,,     we  get  [5691]. 


VlI.vi.^-29.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        685 

If   we  substitute  the  values    of     x,     y,     and   neglect  the    square    of   the 
excentricitj  of  the  moon's  orbit,  we  shall  get,* 


/dq\      s     /fiq\  _  [K'—K]  m-.sm.{v—v')  3Km.clu 


Km         (Jv        .        .r,  r-,    ,s  J^"*        ''"  ^^  ^    i\      r, 

— ^,.--.sin.(2w— 2r')—  -^-,-  — .cos.(2î;— 2«').  2 
2u^.u     dt  ^  ^        )iu\u'  dt  ^  ^ 


[5692] 


*  (3108)     Multiplying  [5689]  by    cos.i',     also    [5690]  by     sin.r,     and  reducing   the 
sum   of  these  products,  by  means   of  the  formulas   [56926, c],   whicli    are  deduced  from 
[22,  24]  Int.,  we  get  the  equation  [5692c/].     In  like  manner,  we  may  obtain  [5692e]  ;  or,     [^^^Sa] 
it  may  be  more  simply  derived    from  [5692<]^,  by  changing     v     into     w+90'*,     where 
it  explicitly  occurs,  in  both  members  ; 

— sin.i)'. cos.!;-)-cos.î)'.sin.j;  ^  sin.(« — i'')  ;  .  [569261 

cos.2K'.cos.r+sin.2i''. sin.i'  =  cos.(i' — 2u')  ; 

sin.2v'.cos.'y — cos.2[)'.sin.ii  =  — sm.[v — 2u')  ; 


[5692c] 


cos.i;. 


-<sin.?;. 


/rfO\  ,    .         fdOX         (K'—K).m°~.sm.(v~v')    3Km  idr  dy  ) 

-p  +sin.r.    -^    =  ^ '—- ^ '-  —  . ^— .cos.î;+-^.sin.i>. < 

\dx  J  \dy  J  M  2(t'    tdt  dt  ^ 

,    Km    idx  ,       n  ,.       dy    .     ,        ^      > 

+  ^/  •  J^-cos.C.-2t.')-^^sm.(.-2.') \  ; 

^Q\  ('^^1         {K'—K).m"-.cos.(v-v')   3Am  C    dx    .  dy  ) 


[56Q2d] 


^  Km    i      dx    .     ^        ^,^       dy  ,  [5^^^^] 

+  2^.'  •  J--^-S'n-(^-2i0-f  cos.(.-2.')  j . 

We  must  substitute,  in  [5692f/,  e],  the  values  of  dx,  dy  [5675i]  ;  and,  in  performing 
this  operation,  we  may  use  the  following  theorems,  supposing  W  to  be  any  angle 
whatever  ; 

dx.cos.W-{-dy.s\n.W  = .sin.(r — W) ^.cos.(z; fV)  ; 


dx.sin.W — dy.cosJV  =  —  —  .cos.(t) — JV)-\ — ^'.sin.  (i; W). 


^9-^"^-^^— ^'';  ;  [5692/] 

[5692^] 


The  equation  [5692/]  may  be   easily  proved  to  be  correct,  by  substituting,  in  the  first 
member,  the  values  of     dx,     dy     [56756],  and  developing  the  second  member,  by  means 
of  [22,24]  Int.     The  equation  [5692o-]   may  be  found  in  the  same  manner;    or,  it  may     [5692/.] 
VOL.  III.  172 


686  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

/f/<?\    dv         (K'—K).m^.dv  ,  „        ^Km    ,    dv 

\dv  J    u'  u'^.u^  ^  ^       Su'.M*        dt 


[5693] 

2u'.  lé        di  ^  ^  '  2u'.  n^        dt  ^  ^' 

dQ\      du  (K'—K^.iif'  du  ,         „        3Aw    du 

— ir     . =  -^^ 1 cos  (t) 1)\ . 

dv)   u^.dv  u'^u^        \U  ^^        ^       2m'. M«   dt 

[5694] 

Km      du 

2m'.  îj-*   dt  ^  ^ 

Density  of 
the  ether, 

?o'be"re-''  "^^^^  vctlue  of  K  is  not  constant.  If  ive  suppose  the  density  of  the  ether 
byTfùnc.  to  be  proportional  to  a  function  of  the  distance  from  the  sun,  and  denote 
u^ce'Lm    this  function  by, 

the  sun. 

be  more  easily  derived  from  [5692/],  by  changing  the  arbitrary  angle  TV  into  W — 90"*. 
If  we  now  put  JV=v,  in  [5692/, g-],  we  shall  get  the  two  equations  [5692j,  7^]  ;  and, 
if  we  put  TV==  — (v — 21»'),  or  v  —  W^2v — 2v',  we  shall  get  [5692/,m],  respectively, 
making  some  slight  reductions  ; 

[5692iJ  dx.cos.vA-dy.s'm.v  = ; 

[5692/1]  f/a;.sin.u — dy.cos.v  = ; 

qv                                       du 
[5692i]  dx.cos.(v — 2v')—di/.s\n.(v — 2v')  = .sin.(2v— 2d') 5.cos.(2y — 2v')  ; 

{11}  du 

[5692m]  — <^a;.sin.(« — 2v') — dy.cos.{v — 2v')  = .cos.(2« — 2v')  -\ — ^.sin.(2i' — 2v'). 

Substituting  the  expressions  [5692i,  /],  in  [5692rf],  and  then,  the  result  in  [5680],  we  get 

[5692].     In  like  manner,  if  we  substitute  [5692A',/«],  in  [5692e],  and  then,  the  result  in 

[5692n]     [5678],  we  get,  by  multiplying  by     —,    the    expression     [5693].      Lastly,    multiplying 

[5693]  by     —  ,     we  get  [5694]  ;  observing,  that  the  term  of  this  expression,  having  the 

factor     — .— ,     may  be  nedected,  as  a  quantity  of  the  order    e^.      For,     —     is  of    the 
dv  dt  ■'  °  dv 


du 
Jt 


|5692o]     Q^^igj.     g     [4826]  ;  and  the  same  may  be  observed  of    —  ,      which    is    evidently   of  the 

same  order  as     —     [5686]. 
dv 


Vll.vi.  ^29.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.  687 

(fÇu')  :=  density  of  the  ether  near  the  earth  ;  [5695] 

it  will  become,  for  the  moon,  in  which  u'  changes  into  u' .cos.(î; — v'),*  [5696] 

(p(î/) .?'(«'). COS. (v — v')  =   density  of  the  ether  near  the  moon  ;  [5G97] 

(f'(u')     being    the  differential  of    ©(?«'),    divided   by     du'  \     so  that  we'  [•''008 ] 
may  suppose, 

K  =  H.^  («')  —  ^^  .  <p'  («')  .  COS. (»—?;').  f^C99] 

This  being  premised,  if  we  neglect  those  periodical  inequalities,  which  do 


*  (-3109)     Substituting     s':=0     [5682],  in  the  expression  of  the  distance     r'     of  the 

earth  from  the  sun  [4777c],  it  becomes     u'=  —,.     If  tlie  quantities  ?■',    u'.    corresponding     L^GOGa] 

to  the  earth,  be  increased  by  ^r',  5m',  for  the  moon  ;  we  shall  have,  by  taking  the 
variation  of  the  preceding  expression, 

Su' = .ôr'=  —  u'^.Sr'.  [56966] 

r  2 

The   radius  vector     r,     drawn  from  the  earth  to  the  moon,  makes,  with  the  continuation 
of  the   radius     r',    an    angle   which    is  represented   by     v — v'  ;     and,   it  is  evident,  on 
account  of  the  great  distance  of  the  sun,  in   comparison  with  that  of  the  moon,  that  the      [5696c] 
moon's  distance  from  the  sun  must  exceed  that  of  the  earth,  by  the  quantity  r.cns.[v — v'), 
nearly  ;    hence,     5  r' =  r.cos.  (v — v').       Substituting   this,    in    [5696?/],     and    putting     [5696rf] 

r  =  -  ,     nearly  [4776],  we  get, 

eu'  =  —  -'  .cos.  {v—v'),     as  in  [5696].  \5696e] 

Now,  the  function  ?(«')  [5695],  corresponding  to  the  earth,  changes  into  cp(u'-\-Su'), 
for  the  moon  ;  and,  if  we  develop  it,  according  to  the  powers  of  M,  by  Taylor's  theorem 
[617],  neglecting  the  square  and  higher  powers  of    hi',     it  becomes, 

(P(«')  +  <5m'.9'(m').  [5696/ J 

Substituting  the  value  of  m'  [5696e],  it  becomes  as  in  [5697].  Lastly,  multiplying 
this  by  the  constant  quantity  H,  we  get  the  expression  of  the  resistance  [5699]. 
Encke,  in  making  the  calculation  of  the  orbit  of  the  comet  [56676],  supposed  the  function  ^' 

p{u'),     or,     9(t)i     to  be  represented  by     9[~,)  =  i^- 


688  THEORY  OF  THE  MOON  ;  [Mec  Cel. 

not  depend  on  the  sine,  or  cosine,  of    cv — 51,     we  shall  have,* 
/■dQ\      dv  H.m^.dv      , ,   ,.         3Hm  ,      dv 

If  we  substitute  the  values,t 

[5701]  w  =  -.  j  1  +e.cos.(ct) — îj)  i  ;         f/i  =  dv.  {1 — 2e.cos.(cv—vi)  ]  ; 

a 

we  shall  obtain, 


*  (3110)  Substituting  the  value  of  K  [5699],  in  [5693],  and  neglecting  the  terms 
which  depend  on  the  sine  or  cosine  of  v—v',  or  its  multiples,  we  get  [5700].  For,  the 
first  term  of  [5699]  H.cp{u'),  being  combined  with  the  second  term  of  [5693],  produces 
the  second  of  [5700]  ;  and,  the  second  term  of  [5699], 

[57006]  T-  •  f'  (  "')  •  ^°^-  ("  —  ^') 


u 


being  substituted  for     K,     in  the  first  term  of  [5693],  produces, 

Hnfi.dv     ,,   ,,  „,  A  Hm-.dv     ,,   i\  ci   \  -i  c  /■  '        \> 

[5700c]  -^-^-.,f'{u').cos-'(v—v')  =  —^--.v'{u').{i-{-l.cos.2.{v—v)l; 

which  gives  the  first  term  of  [5700]. 

f  (3111)     If  we  neglect  the  second  and  higher  powers  of    e,    we   get,  from  [4826], 
[5701a]     the  expression  of  ?t    [5701].     Moreover,  the  mean  motion  of  the  moon  being  represented 
by    t    [56S6],  we  get,  from  [4828]     n  =  1  ;    and  then, 

[57015]  t-]-s  =  v~-^  .sm.(cv  —  ^); 

whose  differential  is  the  same  as  the  value  of     dt     [5701].     These  values   of    u,     dt 
[5701]   give, 

[5701c]  -^  =  u\\\—'\.e.cos.{cv—-a)\\  ^^  '  ft  "^  <?t'.{14-2e.cos.(a'— w)}. 

Substituting  these,  in  the  second  member  of  [5700], it  becomes, 

/rfQ\  1^  =  ^H.m''a\dv.(f'{u').{  \—Ae.cos.{cv—zs)\—:^.a\dv.<?{u').  \  1  — 2e.cos.(CT— ra)  \ 

[5701d]         ^     "  '  ■»  C3  > 

^-lH.ma\dv.  [  ?^— m.9'(«')  \  +a«a''.  J -.?(w')-2m.9'(M')  j  .edv.cos{cv-iz). 

Integrating  this,  we  get  [5702]. 


vil.  vi.§ 29.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        689 


+  H.m.a" .  \  '-. 9 ( ii')—2m.v'( «')  Le. s'm.(cv — ra).         2 


[5702] 


Then  we  shall  have,* 

—5 .    — î^  ^3=  — i.H.in.a^.  ^'.e  .fim.(cv—z,)  ;  [5703] 

clu  J      u    \ds  J  -  w  ^ 

— ^    .  — —  =  l.H.m.(r.  {  — V^ — m.cc(u)  >  .e.  sm.(cv — u).  r.5704i 

\dv  J     xi^.dv       ^  i     u  ) 

Now,  if  we  put, 

a  =  H.m.a^ .  \  ^-^  —  m.^\u')  \  ;  [5705] 


/3  =  H.m.cv^ .  i  ^_|m.a>'(M')  I  ; 


[570G] 


*  (3112)     In  substituting  the  value  of    K    [5699],  in  the  second  member  of  [5692], 
and  neglecting  the  terms   depending  on  the  sine  or  cosine  of    v — v',     or    its  multiples 

[5700a],  it  will   be  only  necessary  to  retain  the  term     ^-^ — '-—      [5692].       Now,    the     fsvoSal 

differential  of    m     [5701],  being  divided  by     dt     [.5701],  gives,  by  neglecting  terms  of 
the  order     e^,     and  observing,  that     c  =  l,     nearly; 

du  «  •        /  N 

■^   =   — --sin-lci)  — ^).  [57036] 

Hence,  the  term  [5703fl]  becomes, 

3Km       e        .      ,  . 

-    2;;W-  „•''"•(" ''-^)  5  [5703c] 

and,  if  we  substitute  —  ^^a'^,    nearly;    also,  the   first  term    of    K     [5699],   namely, 

H.(p{u')  ;     we  shall  get  the  value  of  the  first  member  of  [5692,  or  5703],  as  in  the  second 
member  of  [570-3].     By  similar  substitutions,  we  may  obtain  [5704]  ;  but,  it  is   more    ^'^'^^^'^ 
easily  obtained,  by  multiplying  the  differential  of  [5702],   by 

d  V  e       .      , 

-—  = .sm.(cw  — ^       [5701]; 

dv  a  ^  /       L  J    '  [5703e] 

and  then,  dividing  the  product  by     dv  ;     observing,  that  we  need  only  notice  the  first  line 
of  [5702],  because  the  second  line  produces  terms  of  the  order    e^. 

VOL.  III.  173 


(390  THEORY  OF  THE  MOON  ;  [Méc.Cél. 

we  must  add  to  the  second  member  of  the  equation  [4754],  or  to  the  second 
member  of  [4961]  the  following  function  ;* 

[5707]  V^  ■-  •  sm. (Cl' — vi). 

[5708]      The  value  of     -     [4968]  will,  by  this  means,  be  increased  by  the  quantity! 


*  (3113)     We  have,  very  nearly. 


^+M  =  -     [4S90,4892f/],     and     A^^a,     [48631 


hence, 


[5707a]  i^^A-i^      A  _  A    . 

Vrf«2  ~     )  ■    }fi  aa' 


[57076] 


multiplying  this  by  [5702],  we  get, 

-{-H.m.a\  \  ^^-4m.ç.'(M')  I  .-  .sm.(cv—vs). 


[5707c]      Now,  dividing  the  sum  of  the  expressions  [5703,5704]   by     h^,     or     a,,     and   adding 
the  quotient  to  [57076],  we  find,  that  the  sum  becomes, 

[5707rf]        —H.m.a^.  \  ^î^—m.<p'(u')  \ -^  +  H.m.a\  J  ^^  — |.?n.(p'(M')  ]  .'-.sm.(cv—zs). 

Substituting  in  this,  the  abridged  symbols  ci,  p  [5705,5706],  we  get  [5707]  ;  which 
represents  the  sum  of  all  the  terms  of  [4754],  depending  on  the  part  of  Q  now  under 
[5707e]  consideration  ;  as  is  evident  by  observing,  that  the  first  members  of  the  three  expressions 
mentioned  in  [5707c]  contain  all  the  terms  of  Q  [4754].  If  we  now  connect  the  function 
[5707],  with  the  two  first  terms   of  [4754],   we  obtain  the  following   equation,  for  the 

determination  of    u  ; 

ddu    ,  a.v    .  e      .      ,  . 

[5707/]  0  =  —  +M— — +  ,3  .-.sm.(ct>-«). 

In  which  we  may  change     n,     into     a     [4968]. 


t   (3114)     If  we  put,  for  a  moment,     A= ,     and  neglect  the  part  of  [5707/], 

depending  on     e,     the  eqviation  becomes  as  in  [4963fl]  ;  whence,  we  get,  as  in  [4963rt,  è], 

CL  V 

[5708a]     u  =^—  A  =   — ,     for  the  part  of    u     which  corresponds  to     A.      Now  we  have,  very 
[5708i]     nearly,     u  =  -      [4937n],  whose  variation  gives    5u  = ~,  or    (5a  =  —  a^.6ji;  and, 


VII.  vi.  ^'29.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        691 


—  ;    consequently,  the  value  of    a    will  be  decreased  by    a-a^.v.     We  shall      [5709] 
then  have,  as  in  [4973],  very  nearly,* 


.2d.- 

-1—^  +  P  .  -    ==0.  [5710] 

dv  a 


This  gives,t 


by  substituting,  for     Su,     the  value  of    m    [5708a] ,  and  putting  also    a^=a,    it  becomes 

.'  .     r^-fr>/M  [5708e] 

da  =  —  o-a.v,     as  in  [5709]. 


(3115.)     The  term     p.-.sin.  (cr — a)     [5707/],   is  to   be  added  to   the   second 


e 
a 

member    of  [4973c]  ;     therefore    also,    to   that    of   [4973^],    which    is    deduced    from 
[4973c].     Now,  it  is  evident,  from  [4973A],  that  the  effect  of  this  will  be  to  add  to  the 

e  e  [5710a] 

second  member  of  the  equation  [4973],  tlie  term         p.-,      or      p.-;      without   altering 

a,  a 

[4974].     To  find  the  effect  of  this  additional  term   of  [4973],  it  is  only  necessary  to  notice 
it,  together  with  the  chief  term  of  that  equation, 


[57106] 
dv 

neglecting   the  other   small   term,  which  depends  on     -  .         ;     observing  also,   that    zs 

[49S0],  is  deduced  from   [4978],  which  is  not  altered,  by  the  introduction  of  the  terms     [5710c] 

157071.     Moreover,  it  follows,  from  r4978a,5228o1,  that     c — —      is    nearly    equal    to 

^  A'  -^        ^  [57I0rf] 

unity.     Substituting    this    in    [5710&],  and   neglecting   the     terms   of  the   order     e^,     it 

becomes        — '^'~lf~  '  '°  which  we  must  add  the  term  p.-      [5710a]  ;    and    we    shall     [5710«] 
obtain  [5710],  representing  the  equation  [4973],  adapted  to  the  present  case. 

1(3116).     Putting,  for  a  moment,     -^=x,    and  also  a,  =  a,  we  find  that  [5710]  may     [57iia] 
be  put  under  the  form 

2(fa    ,  ,?x       ,     _, 

~rfr  +  ^"^  =  ^'      °''       —=\?'^^;  [57116] 

whose  integral  is      log.-=JP»)      /    being  a  constant  quantity.     Now,     pv    being  very 

small,  we  have  very  nearly   \^xi  ■=-\o^.{\-\-\pv)     [58]  Int.;  hence  [57116'] 


692  THEORY  OF  THE  MOON;  [Méc.  Cél. 


e 


[5711]  -  =  constant. {l+i/3zj}  ; 


consequently, 


a 


[5712] 

î^ecular 
inequali- 
ties of  ilie 


€  =  constant.  {1 — (a — ^[3).i?}, 


peHgV^     The  ratio  of  the  excentricity  to  the  semi-major  axis  is,  therefore,  subjected  to  a 

and 

«cen-        secular  equation,  arising  from  the  resistance  of  the  ether;  but  it  is  insensible, 

[57131"     ^'^  comparison  ivith  the  corresponding  acceleration  of  the  moonh  mean  motion  ; 

because  this  last  acceleration  is,  as  we  shall  soon  show  [5714],    multiplied 

by  the  square  of  v.     This  resistance  does  not  produce  any  secular  equation  in 

[5713']      the  motion  of  the  perigee  [5710c].* 


[5711c]  -=i_|_J|3y;     consequently,    x  =z  -  ^  f .  {\ -\-\^v) ,     as  in  [5711]. 

rwilrfl     Moreover,  we  have  in  [5709],  a  =  constant  X  {1  — a   ■v\  ;    substituting  this  in  [5711], 
after  multiplying  both  members  by  a,    we  get  [5712].     If  we  represent  the  increments  of 

l_o7Ile]      ^^    ^^   arising  from  this  cause,  by  &a,    5e,    respectively,  we  shall  have,  as  in  [570Sc,5712], 
the  following  expressions; 

[5711/]  Sa=  —  aa  .  u  ;  6e  =  —  e  .  (a  —  i  fi)  .  v; 

e  being  the  constant  factor  of  [5712].     These  values  will  be  of  use  in  the  next  note. 

*  (3117.)     Neglecting  terras  of  the  order    e^  ,    y^,    we  have,  in  [5081^], 

[5714a]  dt  =  a^.\l—2e.cos.cv].dv, 

in  which   cv    is  used  for    c  v  —  w,    for  brevity.       Supposing    this   quantity   to   vary,  by 

augmenting    «    by    5a,    and    e    by    (5  e    [  571 1/],  it  will  be  increased  by 

1  3 

[57Hh]  §  a'.  5a  -ll  —  2e.  cos.cr  \  .  dv  —  2  a~.  6e  .cos.  cv  .  dv. 

Substituting  the  values  [5711/],  it  becomes,  successively, 

3  -3 

— fa.r(^.{  l—2e.cos.cv\.vdv.-]-a''^.e.{2a. — ^).vdv.cos.cv 

[5714c]  3  ==   ,  V         , 

t= — 1«^.  ai'.cZy4-  a^.  (5a — ^).e.vdv.cos.cv. 

The  integral  of  this  last  expression   gives   the  corresponding  increment  of    t  -\- s,     which 
will,  therefore,  be  represented  by 

[5714d]  — 3  ^2-_  (i^^a^  a^.(5a  —  p)  .  e  .^v.sm.cv-\-cos.cv.l  ; 


as   is  easily   proved    by    differentiation,  and  putting     c=l.     We  can    neglect   the  part 
depending  on    e.cos.cv,    which  may  be  considered  as  included  in  the  elliptical  motion  ;  then 


VII.vi.§-29.J  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.         693 

The  expression  of    dt     [5081;^]  gives,  in  the  value  of    t-\-s,     the  terms 
[ôlUdM-l, 

—  f  .o-t?®  4-  (5a  —  ^).ve.sm.(^CV  —  ro),        [Incrementof    HeJ  [57141 

Substituting      ^  +  s  + 2e.sin.(ff — -^      for      r,      we    shall    obtain,    in    the      [^714'] 

^  Secular 

expression  of     v,     the  secular  equation,*  L'fTe'"' 

moon's 

(.V  =  f  .a<'  —  (2a  —  ^).i.e.sin.(cf  —  ^)  ;     [Secular  equation  in  v]  "'[57151 

therefore,  the  resistance  of  the  ether  produces  in  the  moori's  mean  motion,  a 
secular  equation,  tvhich  accelerates  that  mean  motion,  without  producin<f  any      t^'^^^l 
secular  variation  in  the  motion  of  the  perigee. 

We  may  prove,  in  the  same  manner,  that  the  resistance  of  the  ether  does  not      (57171 

produce  any  sensible  secular  equation,  either  in  the  motion  of  the  nodes,  or  in  equalîues" 

the  inclination  of  the  lunar  orbit  to  the  ecliptic.i  v'">'>  ^"'^ 

tioii  are 
insensible. 


putting  ft- =n  ^  =  1    [4S27,5701rt],  it  becomes  as  in  [5714].     This  contains  the  syware  of    r57i4ei 

V  ;  but     Sa,     Se     [571 1/J  depend  chiefly  on  its  frst  power  ;  hence  it  is  evident,  that  the 

secular  variation  of  the  mean  motion  [5714],  must  be  much  more   sensible  than   those  of    [5''14/] 

n     and     e,     as  in  [5713,  &;c.]. 

*  (3US).     Putting     c==l,    and     £=0,     in   [570li],  we  get     /  =  u— 2e.sin.(cf-«).     [57,5^1 
Transposing  tlie  last  term,  and  substituting   in   it     t    for    v,     which   may    be  done,  if  we 
neglect  terms  of  the  order    c^,    we  get  d=  ^  + 2£.sin.(f<  — -n)  [5714'].      Substituting  this 
in    the    first    members  of  [57I56,c],  and  neglecting   e^,   they   become   as    in   the    second     [5715a'] 
members  of  these  expressions  ;  their  sum   gives  the   value  of  the   function  [5714],  as  in 
[57 15 J]  ; 

— f.a«2  = — |-a<2  —  3o..t.e.s\n.{ct — ra)  ; 

(5a  —  ^).i'e.sin.(cr  —  to)  ==  +(5a  —  p). i.e. sin. (c^  —  ra)  ; 

Sum  =— £a;2-j-(2a  — p).<.e.sin.(rt-  to).  [5715^^ 

This  last  expression  represents  the  correction  of    t     [5714, 571 5a]  ;  and  it  is  evident,  that 

we  must  change  its  sign,  to  get  the  corresponding  correction  of    v,     as  in  [5715].  [5715e] 

f  (3119.)     In   finding  the  secular  motions  of    y,     Ô,     depending  upon  the  resistance 
of  the  ether,  we  must  proceed  with  the   equation  [4755,or505lè],  as   we  have  done  with 
[4754, or 4973c],  in  finding  the  secular  motions  of    e,     w,     [5692— 5715]  ;  making  the     [5717a] 
necessary  changes,  to  correspond  to  this  case.     In  examining  the  reductions  of  the  equation 
vor,.  III.  174 


[57156] 
[5715c] 


694  THEORY  OF  THE  MOON;  [Méc.  Cél. 

Hence  it  follows,  that  the  resistance  of  the  ether  can  become  sensible,  in  the 

moon's  mean  motion  only.     Ancient  and  modern  observations  evidently  prove, 

[5718]     that  the  mean  motions  of  the  moon's  perigee  and  nodes,  are  subjected  to  very 

sensible  secular  inequalities.       The  secular  motion  of  the  perigee,  deduced 

from   the   comparison  of  ancient  arid  7ïiodern  observations,  is  less  by   eight 

or   nine   sexagesimal  minutes,  than  that  which  results  from  the  comparison 

of  the  observations  made  in  the  last  century.      This  phenomenon,  of  ichich  no 

doubt  can  remain,  must,  therefore,  depend  upon  some  other  cause  than  the 

resistance  of  the  ether.     We  have  seen,  in  [4983,  &c.],  that  it  depends  on  the 

[5720]     variation  of  the  excentricity  of  the  earth's  orbit;  and,  as  the  secular  equations 

lnTih°L     resulting  from  that  variation  satisfy,  completely,  all  the  ancient  and  modern 

onthf       observations,  ivemay  conclude,  that  the  acceleration,  produced  by  the  resistance 

of  an  ethereal  fluid,  on  the  moon's  mean  motion,  is  yet  insensible. 


[5719] 


moon's 
raean 
iiiotiuii  if 
insensibli 


30.     The   acceleration,  produced  by  that  resistance  in  the  mean  motion 
rs-an      ^/  ^^*^  earth,  is  much  less  than  the  corresponding  acceleration  in  the  moon's 
mean  motion.     To  prove  this,  we  shall  resume  the  formula  [931]  ;  and,  if 
we  apply  it  to  the  earth,  we  shall  get,  in  the  expression  of    6v',     the  term,* 

[5722]  6v' =  — '—-  .ffdv'.d'Q'  ; 


[5717rf] 


[4755],  we  find,  that  the  integral  expression,  in  the  first  member  of  [5702],  is  multiplied,  in 

[57176]     [4755],  by    the    factor     j^  +  ^  ^     which    is    of  the    third   order   in     y     [5034a — b]  ; 

therefore  it  may  be  neglected.  Now,  it  is  on  this  term,  that  the  value  of  a  [5702,  5705] 
chiefly  depends  ;  and  a  produces  also  the  part  of  the  secular  inequality  of  the  mean 
"^  motion  corresponding  to  the  square  of  the  time,  which  is  the  most  important  part  of  the 
efiect  of  the  resistance  of  an  ethereal  fluid  [5714/].  Hence  it  appears,  that  the  remaining 
terms  of  Q  produce,  in  like  manner  as  in  [5713],  only  insensible  secular  inequalities,  in 
comparison  with  that  of  the  mean  motion. 


*  (3120).     The  chief  term  of  [931]  is, 
[5723a]  —.ffndt.AR; 


[5722i] 


which  may  be  reduced   to  the   form    [5722],  by  changing     mit     into     dv     [4828]  ;     àR 

into     AO    [5438];     m-    into     S     [914',  5722'],  and  tlien  accenting  the  letters  to  conform 

to  the  present  notation  ;  the  mass  of  the  earth  being  neglected,  in  comparison   with  that  of 
the  sun,  in  estimating  the  value  of    n- 


VII.vi.§30.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        695 

S    being  the   sun's   mass  ;  supposing  the  sura  of  the  masses  of  the  earth      [5722] 
and  moon  to  be  equal  to  unity  ;  and,  that  the  quantity     Q',     in  the  earth's 
motion,  corresponds  to  that  which  we  have  denoted  by     Q,     in  the  moon's      [5723] 
theory.     Moreover,   the    differential  characteristic     d'     corresponds  to  the 
sun's  co-ordinates.     Then  we  have,* 

(-ri-\    (~j^)'    (   /  '  )     being   the  forces  acting  upon  the  earth,  parallel      [5725] 

to  the  axes     x',     y,     z',     by  means  of  the  resistance  of  the  ether.     If  we 
neglect  the   excentricity  of  the  earth's  orbit,  and  represent  the  element  of      ^    „„, 

°  •'  -^         _  [5/26] 

the  time     dt     by  the  differential  of  the  moon's  mean  motion,  we  shall  have, 
as  in  [5672],  for  these  forces,  the  following  expressions  ;t 


*   (3121).     The  equation  [5724]  is  similar  to  that  in  [5G74]  ;  and,  it  is  evident,  from 
[5673c],  that  the  quantities 

/dq'\           /dq'\  /rfQ'\ 

[l^'r          W>  U^'J'  [5^24a] 

represent  the  forces  acting  upon  the  earth, parallel  to  the  axes  of    x',     y',     z',     and  arising 
from  the  resistance  of  the  ether  upon  the  earth. 

f  (3122).     These  forces  are  represented  by  the  expressions   [5672]  ;  and  we  have,  as 
in  [56876,c,  5681,  5683,  &.C.],  by  neglecting  the  excentricity  of  the  orbit, 

dx  ^  —  a'dv'. s'm.v'  ;  d y' ^a'dv'.cos.v'  ;         dz'  =  a'ds'  ; 

^ilx'2-\-dy'^  +  dz'^  =  r'dq'  =  a'dv'. 

Substituting  these  values  in  the  three  expressions  [5672],  they  become  respectively. 


[5727a] 


E.a\-^-^.  sm.v   ;    -K.a\  — .cos.r  ;    -K  .a\- .  --.  [57276] 

Now  we  have,  very  nearly,     dv  =  mdl     [56S7(/]  ;  substituting  this  in  [5727i],  we  get  the      [5727cl 
expressions  [5727]  ;  which  represent  the  values  of 

m  m  &?)• 

respectively.     Substituting   these  in  the  second  member   of  [5724],  and  also  the  values 

dx' ^  —  a'. mdt. sin. v'  ;         dy'  =  a'.mdt.cos.v'  ;         dz'  =  a'ds'  ;  [5727d] 

which  are  deduced  from  [5727a,c],  we  get, 

d'q=  —  K'.a'^m\dt.  i  sin.V+cos.V  +  ^^.|.' j  .  [5727e] 


696  THEORY  OF  THE  MOON  ;  [Méc.  Cél. 

J     f 

[5727]  K'.a'^.m^.  s'm.v'  ;         — K'.  d^.m^.  cos.  v'  ;         — K'.a^.m. —  ; 

dt 

els' 
[5727]     therefore,  by  neglecting  the  square  of     —,     we  shall  have, 

[572S]  d'Q'  =  —  K'.  a'  \  m\  d  t  ; 

which  gives,* 

[5729]  <5  V'  =  -^-  .ffdv'.  d'Q'  =  1  .  ^ . 

[5730]  We  must  put  K'  =  H'.<f(u')  [5699];  H'  being  a  constant  quantity, 
depending  on  the  surface,  and  on  the  mass  of  the  earth.  Hence,  the  secular 
equation,  produced  by  the  resistance  of  the  ether,  in  the  mean  motion  of  the 
earth,  is, 

[5731]  iV      = •  [Secular  equation  of  tho  earth] 

S 

The    corresponding  acceleration   of  the   moon's  mean    motion   is,  hy  what 
precedes  [57306], 


Neglecting  the  term  depending  on  the  square  of  ds    [5727'],  and  putting  sin.V+cos.V=l, 
it  becomes  as  in  [5728]. 

*  (3123).     Substituting,  in  [5722],  the  value  of    d'Q'  [5728],  and  dv'  =  mdt  [5727c], 
it  becomes,  by  noticing  only  the  part  depending  on    t^, 

[5730a]  l.K'.a'*.m\ffdf-  =  ~.K'.a'\m'U^     as  in  [5729]  ; 

substituting     Z' [5730],  we   get  [5731].     The   acceleration   of  the  moon's  mean  motion, 
depending  on     l^,     is     |  a  i^  [57 1 5]  ;     and,  by  substituting     a     [5705],  it  becomes, 


3 
[5730i] 


i.H.a\mt^[^-^-m.<p'{u')Y, 


which  is  easily  reduced  to  the  form  [5732],  by  using     -,=  «'    [4937w].     Again,   if    we 


3 


[5730c] 


change  the  sun's  mass     m'     [4757"]  into     S     [5722'],  also     w     into  m»,   nearly  [5094], 
we  shall  find  that  the  expression  [4865]  becomes, 

—  —  m,     or     S= — ^>     as  m  [5733]. 


Vll.vi.  s^30.]  EFFECT  OF  THE  RESISTANCE  OF  AN  ETHEREAL  FLUID.        697 

6V   =^    ^.H.(l^.a'.mt^.j3:(u') ^.•'P'(«')f'         [Secular  equation  of  Iho  moon]  [5732] 

S  a^ 
Moreover,  we  have     ~  =  wr     \5130c]  ;    therefore,    the   acceleration    of     [5733] 

«  •'  "- 

the  moon's  mean  motion,  is  to  the  corresponding  acceleration  of  the  earth's 
mean  motion,  as  unity  is  to,* 

2H'.m.  ip(tt')  secular  motion  of  the  earth 


TT  ^r.    /  i\       ™    //  /N>        secular  motion  of  the  moon  ' 
1Z.J3ç(h)  — -.<p'(m)J 


[5734] 


1  •  •  H'.m  1-1  '"        //     l\  I4.  rr-o-T 

consequently,  as  unity  IS  to     -|.  ;     neglecting  the  term ;.<»(?«;.       It      L^'-^^J 

is  evident,  that,t 


*  (3124).     Dividing    the   expression    of     &v'     [STol],  by    that   of    5v     [5732],    and 
Hibstituting     S     [5730c],  we  get  [5734].     If  we  neglect   the  term  of  the  denominator  of    [o'34a] 

[5734],  which  is  multiplied  by  the  small  quantity     —  ;     we    find  that   the  numerator  and 
denominator  become  divisible  by     ç(m'))     and  the  expression  changes  into     i-~n~-  [57346] 

t  (3125)     The  resistance,  which  the  moon  suffers,  must  evidently  be  proportional  to 


square  of  the  moon's  seaii-diameter 
mass  of  the  moon 

and  that  of  the  earth  is  proportional  to 


[5736o] 


square  of  the  earth's  semi-diameter  [5736a'] 

mass  of  the  earth 

Now,  these  quantities  are  to  each  other  as     H    to     H'     [5699,5730];  hence  we  get, 

H'  mass  of  the  moon      square  of  the  earth's  semi-diameter 

H  mass  of  the  earth      square  of  the  moon's  semi-diameter  '  '■  '"^"  J 

If  we  take,  for  the  moon's  semi-diameter,  the  angle  under  which  it  appears  when  viewed 

from  the  earth,  at  its  mean  distance  ;  and,  for  the  earth's  semi-diameter,  the  angle  under     [5736c] 

which  it  appears  when   viewed   from  the  moon,  or  the  moon's  horizontal  parallax  ;  we 

shall   find,  that  the  expression  [STSG?-]  becomes  as  in  [5736].      Substituting   the   values 

JTt 

[5737 — 5738'],  we  get  [5739].     Substituting  this,  and     m    [5117],  in     f--^    [5735],     [5735^] 
it  becomes  as  in  [5740]. 

VOL.  III.  175 


(398  THEORY  OF  THE  MOON;  [Méc.  Cél. 

H'        mass  of  the  moon  square  of  the  moon's  parallax 

H         mass  of  the  earth       square  of  the  app.  semi-diameter  of  the  moon 

From  observation,  we  get, 

[5737]  The  moon's  apparent  semi-diameter  =     943'  ; 

[5738]  The  moon's  parallax  =  3454'  ; 

[5738']     and,  in  [4631],  the  moon's  mass  is     -—     of  that  of  the  earth  ;  therefore, 

we  have, 
[5739]  g-'=^  0,195804. 

Hence   it  folloivs,  that  the  acceleration  of  the  earth^s  mean  motion,  produced 
157401     %  ^'*^  resistance  of  the  ether,  is  equal  to  the  corresponding  acceleration  of  the 
moonh  mean  motion,  multiplied  by     0,0097642     [5736ti]  ;   or,  about  one 
hundredth  part  of  the  moorih  acceleration. 


APPENDIX. 


Presented,  hy  the  Author,  to  the  Board  of  Longitude  of  France 

August  17,   1808.* 


The  object  of  this  appendix  is  to  render  more  complete  the  theory  of  the 
perturbations  of  the  planets,  which  is  given  in  the  second  and  sixth  books.  In 
striving  to  give  to  the  expressions  of  the  elements  of  the  orbits,  the  most  simple 
forms  which  they  can  attain,  we  have  been  able  to  make  them  depend  wholly 


*  (3126)  This  paper  was  given  by  the  author,  as  an  appendix  to  the  third  volume  of 
this  work  ;  it  was  not,  liowever,  published,  till  after  the  appearance  of  the  fourth  volume  ; 
which  is  referred  to  in  several  places,  as  in  [5764',  5975].  The  improvement,  made  by 
Mr.  Poisson,  in  the  demonstration  of  the  permanency  of  the  mean  motions,  which  is 
treated  of  in  [5794' — .5846],  was  made  known  to  the  National  Institute  of  France,  in  a 
paper,  presented  June  20, 1808,  and  printed  in  the  eighth  volume  of  the  JoJirnrtZ  f/e  rEcole 
Polytechnique.  This  first  demonstration  was  followed  by  a  much  more  simple  one,  given 
by  La  Place,  in  this  appendix  ;  and  some  improvements  were  afterwards  made  by  him, 
and  published  in  tlie  fifth  volume  of  the  present  work  [12508,  &ic.].  La  Grange  also  gave 
an  elegant  demonstration,  founded  upon  the  principle  of  the  variation  of  the  constant 
quantities,  in  the  Mémoires  de  l'Institut  de  France,  for  1808,  Stc.  ;  and  in  the  second 
edition  of  his  Mécanique  Analytique.  Subsequently,  the  subject  was  resumed  by  RJr. 
Poisson,  in  the  same  volume  of  the  Journal,  and  in  the  Mémoires  for  1816,  with  important 
improvements;  in  which  he  extended  the  demonstration  of  his  theorem  on  the  mean 
motions,  so  as  to  include  terms  of  the  third  order  of  the  disturbing  masses,  arising  from  those 
of  the  secontZ  order  in  the  disturbed  planet;and  then,byinduction, he  supposes  this  will  hold 
good  for  all  powers  of  the  masses,  so  far  as  they  depend  on  the  elements  of  the  disturbed 
planet.  He  also  demonstrated  this  remarkable  theorem,  '  That  the  perturbations  of  the 
rotatory  motion  of  a  solid  body,  oÇ  any  form,  arising  from  forces  of  attraction,  dejiend  upon 


[5741a] 

[57416] 
[574 1  e] 

[5741d] 
[5741e] 

[5741/] 

[5741^] 


Elemcnls. 

Second. 

Third. 

[5742] 

Foiirth, 

Fifth. 

Sixth. 

700  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.  Cél. 

on  the  partial  differentials  of  a  single  function  [913,  1195,  1258,  i&c.],* 
[5741']  taken  relatively  to  these  elements  ;  and,  it  is  remarkable,  that  the  coefficients 
of  these  differentials  are  functions  of  the  elements  themselves.  These 
elements  are  the  six  arbitrary  quantities  of  the  three  differential  equations 
of  the  second  order  [915]  ;  by  means  of  which,  the  motion  of  each 
planet  is  determined.  Supposing  the  orbit  to  be  an  ellipsis,  which  is 
[5741"]  variable  at  every  instant,  the  elements  will  be  represented  in  the  following 
manner  : 

First.     The  semi-major  axis,   on  which  the   mean  motion  of  the  planet 
depends,  a  ; 

The  epoch  of  the  mean  longitude,  s  ; 
The  excentricity  of  the  orbit,  e  ; 

The  longitude  of  the  perihelion,  to  ; 
The  inclination  of  the  orbit  to  a  fixed  plane,  ?  ; 
The  longitude  of  its  node,  è. 

La  Grange  gave,  a  long  time  ago,  the  above-mentioned  form  to  the 
differential  expression  of  the  greater  axis  [5786]  ;  and  proved,  by  means  of 
[5742']  it,  in  a  very  elegant  manner,  the  invariableness  of  the  mean  motion,  noticing 
only  the  first  power  of  the  disturbing  masses.  This  invariableness  was  first 
discovered  by  me  ;  neglecting,  however,  the  terms  of  the  fourth  and  higher 


[574i;i]  the  same  equations  as  the  perturbations  of  a  slaghpartide  of  matter,  attracted  towards  a 
fixed  centre;'  so  that,  the  precession  of  the  equinoxes,  and  the   nutation  of  the  earth's 

[5741i]  axis,  can  be  expressed  by  tlie  same  formuhis  as  the  variations  of  the  eUiptical  elements  of 
the  planets.     We  had  Intended  to  2,ive  a  particular  account  of  these  improvements  of 

[5741A]  La  Grange  and  Poisson,  together  with  some  notice  of  the  papers  which  Mr.  Lubbock  has 
published,  on  the  secular  and  periodical  inequalities  of  the  planets,  in  the  Transactions  of 
the  Royal  Society  of  London,  in  1830,  1831  ;  but,  we'have  been  induced  to  postpone  this 

[5741Z]  notice,  by  reason  of  the  great  length  of  the  appendix  to  this  volume.  We  shall,  however, 
resume  the  subject  in  the  commentary  on  the  fifteenth  book. 

*  (3127)      The    function   here    spoken  of   is    R     [913].      The  differentials  of  the 
[5741m]   elements    a,     s,     e,     &c.,    are  given  in  [1 177,  1345,  1258,  13376,  Sic]  ;    and  they  are 
collected  together,  with  improvements,  in  [5786 — 5791]. 


[5744] 


VII.App.Int]  INTRODUCTION.  701 

powers   of    the     excentricitics    and     inclinations   of    the    orbits,   which   is      ,,.,,, 

^  [5/43] 

sufficiently  accurate  for  the  purposes  of  astronomy.  I  have  given,  in  the 
second  book.  [1258,1337,  fcc],  the  same  forms  to  the  differential  expressions 
of  the  excentricity  of  the  orbit,  of  the  inclination,  and  of  the  longitude  of 
its  node;  nothing  more  is  required,  than  to  give  the  same  form  to  the 
differential  expressions  of  the  longitudes  of  the  epoch  and  of  the  perihelion  ; 
this  I  have  now  done  in  the  present  appendix. 

The  principal  advantage  of  this  form  of  the  differential  expressions  of  the 
elements  is,  to  give  their  finite  variations,  by  the  development  of  the  function, 
which  is  denoted  by  R,  in  the  second  book  [913,  &c].  If  we  reduce  this 
function  into  a  series  of  cosines  of  angles,  increasing  in  proportion  to  the 
time  [lOllj&c],  we  shall  obtain,  by  taking  the  differential  of  each  term,  the 
corresponding  terms  of  the  variations  of  the  elements.  We  have  endeavored 
to  satisfy  this  condition  in  the  second  book  ;  but,  we  can  do  it  in  a  more 
simple  and  general  manner,  by  means  of  some  new  expressions  of  these 
variations.  These  last  expressions  have  also  the  advantage  of  proving  clearly, 
the  beautiful  theorem  discovered  by  Mr.  Poisson,  on  the  invariableness  of  the 
mean  motions,  noticing  the  square  of  the  disturbing  force.  We  have  proved, 
in  the  sixth  book,  by  means  of  similar  expressions,  that  this  uniformity  is 
not  altered  by  the  great  inequalities  of  Jupiter  and  Saturn  [3906"],  which  is 
the  more  important,  as  we  have  shown  in  the  same  book  [3910 — 3912], 
that  these  great  inequalities  have  a  considerable  influence  upon  the  secular 
variations  of  the  orbits  of  these  two  planets.  The  substitution  of  the  new 
formulas  which  we  have  just  mentioned,  shows,  that  the  uniformity  of  the  mean  [5745] 
motions  of  the  planets  is  not  troubled  by  any  other  periodical  or  secular 
equation.  These  expressions  give  also,  the  most  general  and  simple  solution 
of  the  secular  variations  of  the  elements  of  the  planetary  orbits.  Lastly, 
they  give,  in  a  very  simple  manner,  the  two  inequalities  of  the  moon's  motion 
in  longitude,  and  in  latitude  [5967,5971],  depending  on  the  oblatenessof  the 
earth,  which  have  been  determined  in  the  second  chapter  of  the  seventh  book 
[5357,5389].  This  confirmation  of  the  results,  which  have  been  obtained 
relative  to  these  inequalities,  is  interesting,  because  we  can  get,  by  comparing 
them  with  observations,  the  ellipticity  of  the  earth,  in  as  accurate  a  manner, 
to  say  the  least,  as  by  the  direct  measures  ;  with  which  they  also  agree,  as  [5746] 
well  as  can  be  expected,  considering  the  irregularities  of  the  earth's  surface. 

VOL.  111.  176 


702  APPENDIX,  BY  THE  AUTHOR  j  [MécCél. 

In  the  theory  of  the  great  inequalities  of  Jupiter  and  Saturn,  which  is 
given  in  book  VU,  we  have  noticed  the  fifth  power  of  the  excentricities  and 
inclinations  of  the  orbits.  Mr.  Burckhardt  has  calculated  the  terms  depending 
on  these  powers.  But,  it  has  been  since  found,  that  the  inequality  resulting 
from  these  terms,  is  taken  with  a  wrong  sign.  Therefore,  we  shall  correct, 
at  the  end  of  this  appendix,  the  formulas  of  the  motions  of  Jupiter  and 
[5747]  Saturn,  which  are  given  in  the  eighth  chapter  of  the  tenth  book.  This 
produces  a  small  alteration  in  the  mean  motions,  as  well  as  in  the  epochs  of 
these  two  planets;  and  this  change  satisfies  the  observation  of  the  conjunction 
of  these  two  planets,  made  by  Ibn  Junis,  at  Cairo,  in  the  year  1007.  This 
observation  varies  from  the  formulas,  by  a  quantity  which  is  much  less  than 
the  error  to  which  the  observation  is  liable.  The  ancient  observations,  quoted 
by  Ptolemy,  are  equally  well  represented  by  these  formulas.  This  agreement 
proves,  that  the  mean  motions  of  the  two  greatest  planets  in  the  system  are 
now  well  known,  and,  that  they  have  not  suffered  any  sensible  variation  since 
the  time  of  Hipparchus  ;  it  guarantees,  for  a  long  time,  the  accuracy  of  the 
tables  which  Mr.  Bouvard  has  constructed,  by  the  theory,  and  which  the  Board 
of  Longitude  has  just  published. 

In  the  same  meeting  at  which  I  presented  these  investigations  to  the  Board 
of  Longitude,  La  Grange  also  communicated  his  learned  researches  on  the 
same  subject.  He  has,  by  a  very  elegant  analysis,  expressed  the  partial 
differential  of  R,  taken  relatively  to  each  element,  by  a  linear  function  of 
the  infinitely  small  differences  of  these  elements;  in  which  the  coefficients  of 
these  differences  are  functions  only  of  the  elements  themselves.  If  we 
determine,  by  means  of  these  expressions,  the  differences  of  each  element, 
we  may,  by  proper  reductions,  obtain  the  very  simple  exjn-essions  which  we 
have  given  ;  and,  as  they  can  thus  be  deduced  from  such  different  methods, 
their  accuracy  will  thereby  be  confirmed. 

1.     We  shall  resume  the  expression  of     ede,     given  in  [1262]  ;  putting, 
[5750]     far  greater  simplicity,     p-=l,     we  obtain,* 


*  (3128)      In  the  equations  [1262,5751],  terms  of  the  order  of  the  square   of  the 

[5751a]     jjigjurbing  forces  are  neglected  [1253(7,  &;c.]  ;  but  it  is  correct  in  terms  of  the  frst  order  of 

the  disturbing  forces,  for  all   powers  of  the   excentricities   and  inclinations.     Tiie  value 

_3 

[5751i]     fji.=  l,     being  substituted  in  [541'],  gives    »i  =  a  ^    which  is  used  in  [5785,  &:c.]. 


[5754] 


VII.  App.'^l.]       INVESTIGATION  OF     rf^,     di,     da,     dc,     (fe,     dp,     dq.  703 

ede  =  a.ndt.^ï=7c .  (^)-«-(l  -  «')-^'^»  ^^''^^^ 

In  this  equation,  /  is  the  time  ;  nt  the  mean  motion  of  the  planet  m  ;  [5752] 
a  the  semi-major  axis  of  its  orbit;  e  the  excentricity;  v  the  true  longitude  1-57531 
of  the  planet  ;  R  a  function  of  the  co-ordinates  of  the  tivo  planets  m,  m' ; 
so  that,  by  naming  these  co-ordinates  x,  y,  z,  x',  y',  z',  respectively, 
we  shall  have,  as  in  [949,  949'], 

R  _  m'  .  (^''+H'+^^')  _  ^  .  [5755] 

P  being  the  distance  of  the  two  planets  from  each  other;  so  that  we  shall  have, 

P  =  v/ ! G^'  - ^y  +  (y- i/r+  (^'- ^r \  ;  ^5756] 

r'   is  the  radius  vector  of  the  planet  m'  ;     r     that  of  the  planet  m  ;    lastly, 
the  characteristic   d   refers  only  to  the  co-ordinates  of  the  planet  m  [916']. 

We  may  observe,  that  to  obtain     \-j-\     we  must  develop    R    in  a  series 


[5757] 


of  angles  proportional  to  the  time   t  ;   then  take  its  differential  relative  to     nt,      [5758] 


[5759] 


[57C0] 


and  divide  it  by     ndt,    adding  to  the  quotient  the  partial  differential     (~\ 

^  being  the  longitude  of  the  perihelion  of  the  orbit  of  m.  For,  we  must 
not  notice,  in  finding  the  partial  differential  of  R,  relative  to  v,  the  angle 
nt,  introduced  into  R,  by  the  radius  vector  r  of  the  planet  m,  or 
by  the  periodical  part  of  the  elliptical  expression  of  v,  developed  in  a 
series  of  sines  of  angles,  proportional  to  the  time.  Now,  in  these  functions 
[669],  the  angle  nt  is  always  connected  with  the  angle  — z,,  which  is  [5761] 
introduced  into     R,    by  this  means  only  ;   therefore  by  adding  to  the  partial 

differential     —  ,     the  partial  differential     Ç~\     we  shall  have  the  value*      [5762] 


*  (3129)     The  two  first  terms  of    ,it-}-s     [669],  are  not  connected  with     —  ra,     but, 
It  IS   found  ill  all  the  remaining   terms;  so  that  we   have     v  =  7t( -{-e  +  cp{nt  +  i  —  vs),    [5763a] 
<p  being  the  characteristic  of  a  function.     If,  for  a  moment,  we  consider  iï  to  be  a  function 
of     V,     as    in    [3742],  and  represent  it   by     R=f{v),     we   shall   have,   by   the  usual     [57636] 
notation,     (-j=/'(r).   Substituting   ^    [5763a],  in     R     [57636],  we  get,  ^57^3^^ 

I^=f{nt  +  e  +  cf>{nt-j-s  —  z=)l. 


704  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

'dR\ 
\d7j 


[5763]       of     (t-)'     Hence,  the  preceding  expression  of    ede ,     will  give, ^ 


[5764]  de  =  ^V^-t .( I  _  v/ï^^)-diî  +  "-^^^'.nrfL  (f  ) . 

[5764']      Then  we  have,  as  in  [7886],t 

Its   differentials,  considering  successively,     nt     and     «,     as  the  variable   quantities,  also 

[5763c']  /rf.iw)\  ,,    , 

putting,  for  brevity,     nt-{-s—-a-  =  \v,     (  ~T~  )  =  <?  V^^)'    S'^^' 

[5763i]  W<""^  *  +  *'^"^  "^  '~^^  i  •/'!  "<+  «  +  9  («<  +  s  — «)  i  • 

[5763e]  (^)  =  —  <P'("^  +  s  —  «)  ./'{n<  +  6  +  ?(«<  +  £  —  w)  J. 

The  sum  of  the  two  expressions  [5î63tZ,e],  being  successively  reduced,  by  using  [57G3a,c']^ 
becomes  as  in  [5762]  ;  namely, 

t5^63/]  ^+(^)=/'l,.+  .+  , (,.+  .-«)!=. /'W  =  (^). 

*  (3130)     Substituting  the  value  of      {~-\     [5763/],  in  [5751],  it  becomes, 

[5764a]  cde  =  a.ndtVY^^.  |  ^  +  (^)  ]—-0  -  «^)-d«- 

Dividing  this  by     c,     and  making  a  slight  reduction,  we  obtain  [57G4]. 

t  (3131)     The  formula  [5765]   is   the  same  as  that  which  the  author  has  demonstrated 
in  [7S86],  in  nearly  the  following  manner.     The  first  of  the  equations  [606]  becomes,  by 
[5765a]    changing  the  origin  of    the   time     t,     as    in    [668'];     ni-\-s—u:=u—e.sm.u;     and,  if 
we  also  change     7it     into    fndt,     as  in  [5793],  we  shall  get, 

[57656]  fndt-\-£ — w  =  u — e.sin.M. 

In  which    fndt-\-s     is  the   mean  longitude    of  the  planet    m  ;    fndi-\-s — w     its    mean 
[5765c]     anomaly;     v — «    its  true  anomaly  ;  and  u  its  excentrical  anomaly  [603",  Sic,  668',  669]. 
The  differential  of  [57656],  supposing  the  ellipsis  to  be  invariable,  is, 

|-5765^-|  ndi  =  rfii.(l— c.cos.m)  ; 

and,  as  this  must  also  hold  good  for  the  variable  ellipsis  [1168'"],  we  may  take  the  general 
[5765e]     (jifj-grgntial  of  [57655],  supposing  all  the  elements  to  be  variable  ;  subtracting  from  this, 
the  expression  [5765fZ],  we  get, 

[5765/]  de — dia  =  <?«.(!— e  .cos. w) — de.sm.u  ; 


VII.  App.§l.]        INVESTIGATION  OF     d^,    ds    da,     de,     cfe,     dp,     dq.  705 

,          ,               rfra.fl  —  e.cos.uY       <Ze.sin.M.(2  —  e^  —  e.cos.w) 
d.-d.  =  -  -^-^^^^^^  -  -^ ^-^-^^ ^.  [5765] 

In  this  formula,     u     is  the  excentrical  anomaly  [603" — 604],  and     s    the     [sree] 
longitude  of  the   epoch  [669'].     We  may  put  the  second  member  of  [5765] 
under  the  form,* 


supposing     du,     in  the    second    member,  to  be  restricted  to  the  variations  arising  from    [57G5g] 
s,     zi  ;     instead  of  referring  to  the  time     t,     as  in  [5765fZ].      The  tliird  of  the  equations 
[606]  becomes,  by  changing  the  origin  of    t,     as  in  [5765a]  ; 

tang.è.(i)— a)  =  ^^l±5  .tang.jM.  [g^gg^^ 

If  we  take  its  differential,  supposing     s,     zs,     u,     to  be  the  variable  quantities  ;   and     u, 
to  vary  as  in  [5765^]  ;  we  shall  get,  by  multiplying  by  '2, 

dzs  du  /\  _i_e  2rfe.tang.^M 

~~cos.2J(r— ^)  ""  7ô^u '  \/  T^^e  "^  (l-e).\/III^  '  [^^"^^'J 


Now  we  have,  by  using  [5765A], 

cos.2i(t.-^)  ^  l+tang.^è-("-«)  =  1+ j3^^-tang.2iw=  l+tang.^è«+^.tang.=èw 

1                2e  l^~!:>oK\ 

=  ■ +  , .tane.^iw. 


Substituting  this  in  [5765j]  ;  then,  multiplying  by     cos.*^^  n  ;     and  reducing,  by  putting, 
cos.^i«.tang.J«  =cos.^M.sin.àu  =  J.sin.u  ;     (cos.|M.tang.^it)''=  sin.^âM=  J— |.cos.m  ;        rr.',cK^^ 

Multiplying  this  by     \/    -,  T^  >     and  reducing,  we  get, 

rfra.(l — e.cos.w)        rfe.sin.M 


du  =  — 


^/nr72  1— ea  I5765n] 


Substituting  this  value   of    du,     in    [5765/],  we  get  the   expression  [5765]  ;  in  which     rg^gg  , 
nothing  is  neglected. 

*  (3132)     We   have     — (1— e.cos.M)a  =  — (1  —  e^) -|- e.(2.cos.M— e — ccos-^m), 
as  is  easily  proved,  by  developing  its  first  member.     Substituting  this  in  the  numerator  of    [5767a] 
the  first  term  of  the  second  member  of  [5765],  it  becomes  as  in  [5767]. 

VOL.  III.  177 


706  APPENDIX,  BY  THE  AUTHOR;  [Méc.Cél. 

[5767]        — ctro.^i_e2-}-     ____.(^2.cos.?t  —  c  —  c.cos.^u) —  ^  _^  .(2 — c^ — e.cos.w). 

[5768]      The  excentrical  anomaly     %i,     is  given  in  terms  of  the  true  anomaly     v  —  ro, 
by  means  of  the  equations  [603, 606 J, 

«.(1— e2)  .,  . 

[5769]  r  =  —. — 5^ — 7 — - — ,  =  a.{\  —  e.cos.?*.); 

^  \-\-e.cos.{v — -nr)  ^  ^' 

whence  we  deduce,* 

e+cos.  (v — to") 
[5770]  COS.W  =  -^= ^ ^   ; 

l/l —  ee.smAv — ra) 
[^'^'^J  l+e.cos.(D-«)      ' 

consequently,t 


*  (3133)      Dividing  the   two   values  of    r     [5769]   by     a,     we  get,   by  successive 

reductions, 

(1 — e^)  e.cos.(j> —  «)  +  6^ 


[5770a]  e.COS.W  =  1  ■ 


1  4"  e.cos.(« — vs)         1  +  Ê.cos.(î)  —  «)  " 


[5770a']    Dividing  by  e,  we  obtain  [5770]  ;  and  if  we  put  for  a  moment,  for  brevity,  cos.(« — w)=w, 

it  becomes, 

e  -|- w 


[57704]  COS.M  =  -q:^^i 

whence  we  obtain, 

sm.M  =  V/(l-cos.^«)  =  1/  1  -(i+i^  =  ^1^-,^ =  ^^ 

f^''^°^l  _v/(l-e2)V(I-w.) 

l-[-£W 

[5770^1     Re-substitutingthe  values  of  w=  cos. (« — to),   and   \/(l — w^)  =  sin.(t; — to),    it  becomes 
as  in  [5771]. 

f  (3134)  The  value  of  cos.m  [5770i],  being  substituted  in  the  first  member  of 
[5772nl,  we  get,  by  successive  reductions,  the  expression  in  its  last  member.  In  like 
manner,  from     sin.w     [5770c],  we  get  [5772i], 

2e4-2w  2(1  — e2).w        2(1— e2).w.(l+ew) 

2.C0S.M  —  2e  =  -— ■  2e  =  — — = —- -r„ 

l+ew  1+ew  (1+ew)'' 

[5772al  ^^_^2^ 


(1+ew) 


,.{  2w+2ew2}  ; 


VII.Api).§l.]      INVESTIGATION  OF     d^,     ih,     da,    de,    dz,,  dp,     dcj.  707 

r .  (2.C0S.M  — e — e.cos.u) ^  .  (2 — e^ — e.cos.w)  1 


/l— ee    ^  1 — e^ 


. {2.cos.(« — Ts)-\-e-\-e.cos.^v — «)!        ,  _, 

=   V^l— e^.^ \,  ,  T ^^^ ^.erf^  2       [5772] 

}l-|-e  .cos.(î; — rajj'' 

•^  jl-(-e.cos.(î; — rajp  "■ 

Substituting  the  values  of    e(h,     de     [1258],   we  find,  that  the    second 
member  of  the  equation  [5772]  can  be  reduced  to  the  following  form  ;* 


('-'•'      !e_e..|. 


(14_ew)2  •»  >•  [577261 

The  sum  of  these  two  expressions,  gives, 

2.C0S.M  —  e  —  e.cos.^M  =  - — ; _   5  2w+e4-evv^  ? .  rK'>'m  ^ 

(l+cw)2  >■      ^  ^       ^  [5772c] 

Substituting  this  in  the  term  which  is  connected  with  dis,  in  the  first  member  of  [5772], 
get  the  term  depending  on  dzs ,  in  its  second  member  [5772,  line  2].  In  a  similar  manner, 
we  get,  from  the  value  of    cos. m     [5770i], 

2  f  \  /"         («+w)\  /eew  — w\ 

e-' —  e.cos.M  =  eJe  — cos.m)  =  e  .     c  —  -^ — — -  )  =  e  . ) 

^  ^  V  1+ewy  \   1+ew  J 

[5772cf] 


l^ew 

Adding  to  the  first,  and  to  the  last  members  of  this  expression,  the  quantity     2.(1  — e^)  ; 
we  obtain, 

€W  (  I  —  C^^ 

2  —  e^— e.cos.M  =  2.(1— e^) —    .  (1— e^)  = -^^ ^  .  J2.(l+ew)  —  ew  j 

1-f-ew  14-ew      '     ^     '       /  i 

1  +  ew     '    ^      * 

H»„„o      2  — e^— e.cos.M        2+ew  ,,•,•.,         .  .  /i:=i2.sin.(t>-w) 

Hence =  ■— —  ;     multiplymg  these  by     sm.M  = ^     [K770f-\ 

1  —  e2  1+ew  fjb  J  l-\-c^v  P'7^/] 

[5771];  and  substituting  the  result  in  the  term    depending  on     de     [5772 line  1],  we  get 

the  corresponding  term  of  the  second  member  [5772  line  3]. 

*  (3135)     If  we  substitute     f^  =1     [5750],  in  [1258],  we  shall  obtain  the  following 
expressions  of    ed-a,     de,     in  which   terms  of  the  order  of  the  square  of  the  disturbing     [5773a] 
forces  are  neglected  [1253']  ; 


708  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

[5773]  Za.ndt.r.l—    ]     ;  [Value  of  the  function  57721 

[5774]     and,  as  we  have     r.f— j  =  «/  —  j     [962],  it  becomes, 

t^'^^^1  2a^.7ldt.     •(-;—).  [Value  of  the  function  5772] 

\daj 
Hence,  the  expression  of    di — (Zro     [5765]  gives  the  following  very  simple 


[57736]     edra  =  — |^;=.sin.(D— w).  { 2+  e.cos.{v—zi)  } .  (^~  j+a^.  ndtyi-e^.  cos.{v—!^}.(^~j   ; 
[5773c]        <Ze  =  — ^^g.{2.cos.(j;— :;i)+e+e.cos^(t)— 5!)}.(^^j— a2.n(Z^v/i^2.sin.(i;— î:).(^— j. 

These  are  to  be  substituted  in  [5772  lines  2,3]  ;    and,  in  performing  the  operation,  we 

may  neglect  the  part  depending  on     i~J~]  7     because,    the  terms   depending    on     edzr 

[5773d]  |-5772iij,e2,  5773&],  are  equal  to  those  depending  on  de  [5772  line  3,  5773c]  ;  and, 
they  have  different  signs  ;  so  that  they  mutually  destroy  each  other  ;  as  is  easily  seen 
by  the  mere  inspection  of  the  formulas.     The  remaining  part  of  the  second  member  of 

[5773  1  [^"'^^1'  arising  from  the  substitution  of  the  parts  of  [57736,  c],  depending  on  (^  j, 
becomes,  v.ithout  any  reduction,  as  in  [5573/]  ;  omitting,  for  the  sake  of  brevity,  the 
symbol    îï,     which  is  connected  with  the  angle     1; — sr,     as  in  [4821/]  ; 

rw7Qn  (  — e  )•",:"     ^  f        )  .  j  (2.cos.«+e+c.cos.3j;).cos.t)  +  (2+e.cos.t)).sin.2«J. 

lonaj  i  (l-|-e.cos.v)''     \dr  / 

The  terms  of  the  factor,  between  the  braces,  being  arranged  according  to  the  powers  of 
e,     and  then  successively  reduced,  become, 

[5773^]    2.(cos.2«+sin.2i;)-fe.cos.D.^l+(cos.3u+sin.2y)}  =  2+e.cos.u.|l+l|=2.|l+e.cos.r}. 

Substituting  this  last  expression  in  [5773/],  it  becomes, 

2.(1- e2)        „      ,^    /dR\ 

which  is  easily  reduced  to  the  form  [5773],  by  the  substitution  of, 

[5773i]  r  =    ,°_;^^~'''       [603]. 

*•  ■■  1+e.cos.  «      '■ 

Lastly,  the   substitution   of  [5774],  in  [5773],  gives  [5775],  for  the  value  of  the  second 
member  of  the  equation  [5772]. 


VII.  App.§l.]        INVESTIGATION  OF     f/^,     di,    da,     de,     (fo,     dj),     dq.  709 

equation,  which  was  lirst  discovered  by  Mr.  Poisson  ;* 

ds  =  (h .  (\—^T=Tc)+2a\  (^)  .ndt.  [5775'] 

\(l(Z  J  Poissoii^s 

expression 

If  we  refer,  as  m  [1030',  &c.],  the  motion  of  the  planet    in,   to  that  of      ds. 
its  primitive  orbit,  and  put,  as  in  [  1 032] , 

p  =  tang. <p  .sin. 0  ;         q  =  tang.ç  .  cos.^  ;  [5776] 

(p    being  the  inclination  of  the  orbit  [1030'],  and   ô    the  longitude  of  its 
ascending  node,  we  shall  have,  as  in  [13376,ô7516j,t  ^^'^'^'^^ 

,  df  /dR\ 

'^P=-sya.{i-ce)  •  \Tq)    '  [5778] 

,  dt  /dR\ 

Now  we  have,  by  ^  44,  of  the  second  book, f 

0  -  O  ■  *'  +  (f  )  ■"'  +  (")■""  +  (?)  ■  "■  +  (?)-*+(?)-''»^    '-»' 


*  (3136)     The  expression  of  ds — dzi   [5765]  is  reduced,  in  [576/^,  to  three  separate 
terms  ;  of  which  the  Jirst  is     — dzi.\/ 1— e^ .     The  second  and  third  terms  constitute  the     [5775a] 

first  member  of  [5772],  which  is  successively  reduced  to  the  form     2a^.ndt  .  (  i~),     in 

[5775]  ;  hence  we  get, 

ds—d^  =  —  dv!.  /i:rr2-}-2a2.  ndt .  (^)  ;  [57756] 

and,   by  transposing    — dzr,  we  obtain  [5775']  ;  which  is  correct  in  terms  of  the  order  m',     [5775c] 
as  in  [5773a]. 

t  (3137)     We    have     an  =  a~*     [575 li]  ;    substituting    this    in    [1337i],  we    get 
[5778,  5779]  ;  which  are  exact  in  terms  of  the  order     m'     [1337iline  3].  "■' 

J  (3138)     R     is  a  function  of    fndt     [5793],    and  of  the  elements     a,     e,     zs ,     s,     [578031 
p,     q.     Now,  we  may  take  its  differential,  relative  to     t,     considering  the  elements  as 
constant,  and  the  ellipsis  invariable.     We  may  also  take  it,  supposing  all  the  quantities   to 
be  variable,  as  in  [1168', &ic.].     The  first  of  these  differentials,  being  subtracted  from  the     [57806] 
second,  gives  [5780]. 

VOL.  III.  178 


710  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

moreover,  we  obtain,  from  [1177,5750], 
[5781]  da  =  —2a\àR  ; 

/'dR\        AR 


(nH\  n  H 

—-)  =  —  ;    because  the  angle    nt     is  always  connected  with    += 


.* 

5 


[5783] 


[5784] 


therefore,  by  substituting  the  preceding  values  of     da,     de,     d?,     dp,     and 
dq;     we  shall  have  this  very  simple  equation,! 

,               a.ndt.\/\ — ce     f<JR  \ 
d.  =  — ^_  j  ; 

which  gives, 


*  (3139)     We  see,  in  [953,954,  Sic],  that     ni     is  always  connected  with     s,     in  the 

'•'       "J     form  of    nt-\-s ,     or  rather    fndt-\-s     [5793]  ;  so  that  if  we  suppose     R    to  be  a  function 

of  fndt-\-î ,    we  may  represent  it  by     R  =  f{fndt-\-s)  ;    and,  by  using  a  notation  similar 

to  that  in  [5763c],  we  have    (~\=f\fndt-\-i).     and    i-r)'=f'{fndi-\-E);     whence 
[57826]  ^      ''  ^   ^^ 

we  get    (  —  j  =  [  — -  j ,     which  is  equivalent  to  that  in  [5782]. 

t  (3140)     Of  the  six  terms  of  which  the  function  [5780]  is  composed,  the  fifth  and 
sixth  destroy  each  other,  by  the  substitution  of  the  values  of    dp ,     dq     [5778,5779],  as 

[57830]     is  evident  by  inspection.    Again,  the  second  term  of   ds    [5775'],  namely    2a^.i—\.ndt, 

being  substituted  in  [5780],  produces, 

fdRX        ,      fdR\        ^  ,  fdR\     ,„ 

and  this  is  destroyed  by  means  of  the   first  term   of  [5780],  namely     (-—\.da,     as  is 

evident,  by  the  substhution  of    da    [5781].     Hence  the  function  [5780],  is  reduced  to  the 

i^ree  terms  depending  on     de,    d-a,    de;     taking  for     ds,     the  first  term  of  [5775']  only  ; 

[5783c]     namely,     ds  ^  dzT.\\  —  \/l—e^;     hence  the  function  [5780]  becomes, by  the  substitution 

of  this  value  of    ds,     and  that  of    (~\     [5782], 

/dR\      ,      ,     (  /dR\    ,  àR    ,^         ^ ^  ■)     , 

[5783.]  0  =  ^-  )  .  c^e  +  I  (yj  +  ^^  •  (1  -  /l-e^)  \  •  d^- 


VII.  App.§l.]       INVESTIGATION  OF     d^,     ds,     da,     de,     dzs,     dp,     dq. 


711 


Connecting  together,  in  one  table,  these  different  equations,  we   shall  have, 

by  observing,  that     n^a^     [57516],  and,  that  the  sign     d,     affects  only      1-5785] 

the  co-ordinates  of  the  body  m  ;  * 


Now,  tlie  value  of    de     [5764),  can  be  separated  into  two  factors,  so  that   we  may  put  it 
under  the  following  form, 

a.ndt.\/  i—e'i 


(  /dR\    ,   AR     ,  , ,  ) 


as  is  easily  proved,  by  multiplying  the   terms.     Substituting  this   in  [5783f/],  and   then 


dR 


dividing  by  the  common  factor     ("T"'  )  +  "37  •  (  '  — \/l— e^)  ,     we  get, 


dfi 


0  = 


a.ndi.\/l — c'S 


^f)  +  -^ 


*  (3141)  The  equations  [5786 — 5791],  are  the  same  as  those  which  are  given 
in  [5731,5784,5764,  5783,  1337i],  respectively.  The  equations  [5787—5791]  are 
correct,  in  terms  of  the  Jjrst  order  of  the  disturbing  masses,  for  all  powers  of  the 
excentricities  and  inclinations  ;  but,  some  terms  of  the  order  of  the  square  of  the 
disturbing  masses  are  neglected. 


[5783£] 


[5783/] 


whence  we  obtain     dzg     [5783].     Substituting  this  value  of    d-a,    in  that  of    de  [5775'], 
we  get  [5784].     The  expressions  of    cZra,     ds     [5783,  5784],  are   exact  in  terms  of  the     [5783^-] 
order     m',     for  all  powers  of  the  excentricities  and   inclinations  ;  but  some  terms    of  the 
order     wi'^     are  neglected. 


[5786a] 
[57866] 


[5786c] 


We  may  observe,  that,  in  estimating  the  values  of  dp,  dq  [5790,  5791],  we  have 
taken  the  primitive  orbit  of  the  disturbed  planet,  for  the  fixed  plane  ;  so  that  p,  q,  are 
considered  as  very  small  quantities,  of  the  order  of  the  disturbing  masses;  whose  squares 
are  neglected.  To  avoid  this  restriction,  the  author  has  given  other  forms  to  these 
expressions  in  [12528,  12529]  ;  by  taking  another  fixed  plane  independent  of  the  primitive 
orbit.  Then,  if  y'  be  the  inclination  of  the  orbit  of  the  disturbed  planet  to  thisneio 
plane,  and  è'  the  distance  of  its  node  from  a  fixed  point  in  the  same  plane,  we  shall 
have,  instead  of  p,  q,  dp,  dq  [5776,5790,5791],  the  system  of  equations  [5786e — g],  t^^gQji 
representing  the  values  of  p,  q',  dp',  dq'  ;  corresponding  to  this  plane.  From  these 
we  easily  deduce  the  values  of  dy',  d6'  [5786/t,iJ.  The  investigation  of  these  equations 
is  given  by  the  author  in  [12513 — 12537]  ;  and  it  is  unnecessary  to  repeat  it  here. 


p'  =  sin. 7'.  sin. 


q'  =  sin. y'.  cos. 


[12520] 


[5786e] 


712 


APPENDIX,  BY  THE  AUTHOR; 


[Méc.  Cél. 


[5786] 


[5787] 

Differen- 
tials of  the 
elements, 
exact  in 

[5788] 

terms 
of  the 
order  m'. 

[5789] 


[5790] 

[5791] 
[5792] 


da  =  —  2a\dR  ;  (1) 


de  = 
(/ra  = 
dip  = 


a.ndt 
V/l— e 


(  !  -  v/]^?).di?  +  ^H^TE?.n./^  (g)  ;  (3) 

(4) 
(5) 


e  '[Te    '    ' 


dR 

^1 


a.ndt         f^^\ 


^l_e2  *  \di)J 


(6) 


[5793] 
[5793'] 

Moan 

motion. 

[5794] 

[5794'] 


We  may  substitute,  ia  these  equations,     ndt .  (-f)     for     dR    [5782],  and 

bj  this  means,  reduce  the  preceding  expressions,  so  as  to  contain  only  the 
partial  differentials  of  the  elements  ;  but,  it  is  as  simple,  to  retain  the 
differential     dR. 

In  the  motion,  considered  as  elliptical,  we  must  substitute    fndt    for    nt,'* 

if  ive  wish  to  be  rigorously  correct  ;  now,  n  =  a~^  [5785]  ;  therefore,  by 
putting  2,  equal  to  the  mean  motion  of  the  planet  m,  we  shall  have 
[1183,5750], 

^  ^  fndt  =  3ffa.ndt.dR.  (7) 

2.     From  these  equations,  ice  easily  dedtice  the  same  result,  as  that  which 
was  discovered  by  Mr.  Poisson,  relative  to  the  invariableness  af  the  mean 


[5786/] 
[5786g] 
[5786A] 
[5786i] 


dq'z= 


a.ndt 


v/ï: 


.cos.^ 


dR\ 


dy'  = 


a.ndt 


•'•\dp')   ' 


d& 


\/l_e2.sin.7''  \dê'J    ' 

a.ndt  /dR  \ 

i/l_e2.sin.7    \dy/ 


[12528] 
[12529] 
[12536] 
[12537] 


•(3142)     We  have  the  differential  of  the /rsi  order     d^^=  ndt     [1180",  or  5794], 

[5794a]    ^jjich  corresponds  to  the  variable  ellipsis,   and,   therefore,  also,  to  the  invariable  ellipsis 

[1168'].     In  the  invariable  ellipsis,  we  have     n     constant,  and  its  integral  is     2^=nt-\-s; 


VII.App.{-2.]        TERMS,  IN  ^,  OF  THE  ORDER  m^  mm',  m'm",  he.  713 

motions  of  the  planets  ;  noticing  the  square  of  the  disturbing  force.     If  we 
denote  anj  finite  variation  by  tlie  characteristic    5,    and   vary,  in    R,    only    sjmbui 

H'/ta?  relates  to  the  planet  m  ;    observing,  tiiat     \~7~)  ^  ~1      [5782]  ;     we    [5794 '] 

shall  have,* 

Substituting,  for     âa,     6e,     or,,     &c.,  the  integrals  of  the  preceding  values 
of    da,     de,     f?=i,     &c.   [5786,  &c.],  we  shall  have,t 

'I'erina  of 

ATI  ^^' 

Ti  Ult  ,   /-       7.\  ,         of  the 

ôR    =    —-    .   Ô  (fndt)  1        order 


7ldt  "  m'-' 

arising 
from  the 
variation 
2       of  the 
elemeata 
of  the 
planet  m. 


+  ^«--lS->*-(T!)-(f)-/^^i 

+  =^-Kf)->*-(S)-(?,)>*-(f)J      * 
+  .^.-K?)->-CI)-(")-/--Q|-      « 


but,  in  the  variable  ellipsis,  n  is  variable,  and  we  have  ?_=fndt-{-s.  Hence  it  is 
evident,  that  the  mean  motion  7it,  corresponding  to  the  invariable  ellipsis,  must  be 
changed  into    fndt,     in  the  variable  ellipsis,  as  in  [5793]. 


[57944] 


*   (3143)     R    IS  a  function  of   fiult,     and  of  tlie  elements     s,     a,     e,     -a,     p,     a  ; 
now,  if  these   quantities   vary  by  the    increments     3. fndt,     6s,     6a,     6e,     6zr,     6p,     on,      [5795a] 
respectively,  we  may  obtain  the  development  of    R,     in  a  series,  proceeding  according  to 
the  powers  and  products  of  these  increments,  by  means  of  the  formulas  [610 — 612, &ic.]. 

If  we  retain    only   the  first   power   of  these  quantities,  and  put,   for     (  —  V     its    value,     forgsft] 


deduced  from  [5782]  ;  namely,     --   ;     the  increment  of    R    will  become  as  in  [5795].      [5795c] 

This  equation  is  correct  in  terms  of  the  order  m'^;  because,  R  [5755J  is  of  the  order  m'; 
and    the   variations     6s,     6c,     Stc,    which   depend    on    R,    are   also  of  the  order    7n'; 
therefore,  the  terms  of  the  second  member  of  [5795]  are  of  the  order    m'^;    and  the     i^'^^"] 
neglected  terms  of  the  order     R6s^,     R6e^,    he,  must  be  of  the  order    m'^. 

t  (3144)     The  integral  of  the  equation  [5786]    is     a  ;=  constant  —  2.fa-.dR;     the     [5796a] 
VOL.  III.  179 


714 


APPENDIX,  BY  THE  AUTHOR; 


[Méc.  Ctl. 


[5797]      To  obtain  the  value  of  d  .  ]  àR -.i(fndt)i,  given  bjthe  equation  [5796],^ 


constant  quantity  being  equal  to  the  value  of    a,    at   tlie  commencement    of  the  integral. 
[57966]     Hence  the   increment  of     a,     is  represented   by     lîrt  =  —  2  fa^.  dR  ;     so,   that   if   we 
put    fdR  =  R',     and  integrate  by  parts,  we  shall  have,  successively, 

[5796c]  Sa  =  —  2  fa^.  dR  =  —  2  a^.  R'  +fR'.  4  ada  ; 

as  is  easily  proved,  by  taking  the  differentials  of  these  expressions  of    (Sa,  and  re-substituting 
rWQôc'l     R' =  fdR .      Now,     R'      and     da      [5786],  are    botli    of   the    order     m' ;     therefore, 
fR'.4ada,     is  of  the  order     m'^  ;     and  if  we  neglect  terms  of  this  order,  in     Sa,     which 
will  only  produce  terms  of  the  order     m'^,     in  [5795],  we  shall  have, 


[5796rf] 


[5796e] 


6a 


2fa^àR  =  —  2a^.fdR. 


[5796/] 
[5796êr] 
[5796A] 
[5796i] 
[5796ft] 


Hence  it  appears,  that  in  finding  the  integral  of  a-.  dR  ,  we  may  bring  the  factor  a^ 
from  under  the  sign  of  integration  ;  neglecting  terms  of  the  order  ?«'^.  For  similar 
reasons  we  may  bring  a,  e,  from  under  the  sign  J^,  in  the  integrals  of  the  other 
expressions  [57SG — 5791],  leaving  for  symmetry,  «  under  that  sign,  connected  with 
dt ,     as  in  [5794,  5795, Sic]  ;  hence  we   get  the  following   expressions,  which  represent, 

respectively,  the  integrals  of  the  five  equations  [5787 — 5791]  ; 


Ss  =  — 


,,  _     "V}=:îî  .  (i-\/i— e)  .fdR  +  "-±^-11^ 


Jndt 


/dR 


a.\/\ — ce       /•   , 
(5a  = .  Jndt . 


dR 

Je 


— ==   .  fndt .     T-  )  ; 

V/l-ee     ^  \dq  J 


Sp  : 


a  ^  ,     /dR\ 


[5796i]      Substituting  these,  and  also     5a     [5796rf]  in   [5795],  we   get   [5796],  which  is  exact  in 
[5796m]     terms  of  the  order     m'-.     If,  for  brevity,  we  represent  by     R,     the  four  lower  lines  of 
the  second  member  of  [5796],  we  shall  obtain,  by  substitution  and  reduction. 


SR-^  .5{fndt) 
ndt 


R,) 


[5796n] 

[5796o]    so  that    dR,     represents  the  value  of  the  function  which  is  mentioned  in  [5797]. 

*  (3145)     If  we  vary  in     R,     what  relates  to  the  planet  m,  as  in  [5794",  &ic.],  we 


VII.App420         TERMS,  IN  ^  OF  THE  ORDER  n?,  mm',  m'm",  &ic.  715 

we  must  take  its  differential,  relative  to  the  quantities  corresponding  to  the 
planet  m  only  [5785].  To  obtain  the  differential  relative  to  the  elements  of 
that  planet,  it   tvill   be  sufficient  to  suppress  the  sign    f,     which   has  been 


shall  get  the  expression  of    &R   [5796]  ;  or  the  equivalent  expression  [5796m]  ;  and  the 
object   of  the    author,   in  [5797 — 5812],  is   to  prove,  that     à.ôR     contains    nothing  but     [5797a] 
periodical  quantities.     The  value  of    à.SR,     deduced  from  [5796n],  is  of  the  following 
form  ; 

d.6R=dA~.  S  (fndt)  J  +  dR.  [57976] 

The  calculation  in  [5798 — 5806]  is  to  prove,  in  the  first  place,  that  the  second  term  of 
this  expression  d/î, ,  produces  periodical  quantities  only  ;  the  process  in  [5807 — 5812] 
serves  the  same  purpose,  relative  to  the  other  term  ;  namely, 

In  these  calculations,  the  terms  of    R,     are  supposed  to  be  represented  by, 

M.fNdt  —  N.fMdt     [5800]  ;  ^^^^^^^ 

and,  it  is  very  easy  to  reduce  them  to  this  form.     For,  if  we  change    fdR     into  fiidt. — 

ndt 

in  [5796  lines  2.3],  for  the  sake  of  symmetry,  we  shall  find,  that  any  one  of  the  lines  of 
the  function  [5796  hnes  2 — 5],  is  composed  of  two  terms  of  the  form, 


[5797e] 


[5797/] 


A.\R,  .fndt .  R,—R,  .fndt  .R^\; 

A  being  the  factor  without  the  braces;  and  R^,  R^,  the  differential  coefficients, 
depending  on  the  partial  difierentials  of  R,  which  occur  in  that  line.  Now,  if  we  put 
AR^  =  M  ;     ni?3  =  iV  ;     the  preceding  expression  becomes, 

M.fNdt-^.fndt."^-,  tS^9^/'] 

M    and    iV    being  each  of  the  order  m'  ;    therefore,     MN     is  of  the  order    m'~  ;    and, 

a 
if  we  neglect  terms  of  the  order    m'^,    we  may  introduce  the  factor     -  ,     of   the  second   [5797/"] 

n 

term  of  [5797/'],  under  the  sign    /;     and  then,  by  reduction,  the  expression  becomes, 

M.fNdt  —  N.fMdt,     as  in   [5800].  [5797^] 

Similar  processes  and  redactions  are  used,  in  calculating  the  partof  d.iiî,    arising  from  the 
variation  in     SR,     relative  to  the  planet  m',   in   [5813,  Sic.];  and  those  relative  to  the     ^^'^^'^^' 
planet  m'',  in  [5832,  Sic.]. 


716  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

introduced  only   by  the  integrals  of  the  differeiitial    expressions  of  these 

[5798']     elements   [5786 — 5791]  ;    and    then,    that  expression  becomes    identically 

nothing  ;*     so    that,    if  we    wish   to   obtain   the  differential     d     of   the 

[5799]      function    ôR Mfndt),     it  will  suffice  to  take  its  differential  relative  to 

ndt 

nt,      noticing    only    the    quantities    without  the   sign    f    [5798e].      The 
expression  of  this  function  is  composed  of  terms  of  the  form, 
[5800]  M./Ndt—N./Mdt     [5797^].  !Fu„ct.o.«) 

M     and     N     may  be  developed  in  terms,  depending  on  cosines  of  angles  of 
the  following  forms  ;t 

[5801]  M=k.cos.(i'n't—inti-A);  N=k'.cos.(i'n't—i7it+A'); 

[5802]      i'     and     i     being  any  integral  numbers,  positive  or  negative.     We  must 


*  (3146)     The  integrals  of  the  expressions  [57S6 — 5791],  introduce  the  sign    /    in 

the  values  of  the  variations   of  the   elements  of  the   planet  m   [5196f—k]  ;  and  by  this 

[5798a]     means  they  occur  also  in  [5796];  and,  as  these  integrals  haverel'erence  to  the  elements  of 

m,  their  differentials  relative  to  the  characteristic     d     [5785],  must  be   equivalent  to   the 

complete  differentials  ;  so  that  we  shall  have, 

[■57985]  d  .fJVdt  ==  JVd  t  ;         d  .  fMd  t  =  Mdt . 

Hence  the  differential  of  the  function     R^     [5800],  relative  to     d,     is, 

d«,  =  AM .  fJVdt  —  dJV  .  /Mdt  -f  MJVdt  —  MJYdt . 

The  two  last  terms  of  this  expression   destroy  each  other,  as  in   [579S']  ;  and  we  finally 
get, 
[;5798d]  dR,  =  dM .  fJVdt  —  dJV .  fMdt . 

Hence  we  obtain  the  same  rule  as  in  [5799],  for  finding  the  differential  of 

rgyggg,  R,=    M    .  fJVdt    —    JV  .  fMdt  [5800]     ] 

namely,  by  taking  the  differential  of    R^,     supposing  the  terms  without  the  sign    /,     to 
be  the  only  variable  quantities. 

t  (3147)     The  functions     M,     JV     [5797/],  depend  on     R,     which  is  of  the  same 
[5801tt]    form  as  the  assumed  values  of    M,     JV    [5801]  ;  as  appears  in   [957'"].     Substituting 
these  in  [5803],  we  get  [5804]. 


VII.App.>§--2.]         TERMS,  IN  ^,  OF  THE  ORDER  w^,  mm',  mm",  Uc.  717 

[5803] 


combine  these  two  terms  together,  to  obtain  the    non-periodical    terms    in 
AAM.fNdt — N.fMdt]  ;     then  this  function  becomes, 


k.indt.sm.Ci'n't — int-\-A)  .  fk'dt.cosJi'n't — int-{-A')  1 

"^  \  _  [Function  .lfi,l  [5804] 

—k'.indt.sin.(i'7i't — int-{-A')  .ykdt.cos.Çi'n't — int-j-A).  2 

The  integrations  which  are  indicated  in   this  function,  being  made,  we  find,      [5305] 
that  the   terms  destroy  each  other,  and  the  whole   expression    vanishes.* 
This  agrees  with  what  we  have  demonstrated,  in  [3906'],  relative  to  the  great 
inequalities  of  Jupiter  and  Saturn.     The  expression  of 

d  .<  iR .  6.  fndt  >  ,  [5806] 

is,  therefore,  a  periodical  function. 

The    expression    of     à .}  —- .à  .fndt   >,        contains     only     periodical 
quantities  ;  for,  we  have,t 

Substituting  for     on,     its  value  f     in^Sfan.dR,     we  shall  have,  [5808] 


*  (3148)     The  integrations,  which  occur  in  [5804],  are  made  in  the  usual  manner,  by 
changing  co«.  into  Mw.,  and  dividing  by     iW  —  in;     and   when   this   is  done,  the  terms      |C805a] 
mutually  destroy  each  other.     We  may  remark,  that  the  coefficient  of    t ,     in  the  values 
of    Jli,     A*     [5801],  are  ejMoZ  to  each  other,  being    represented  by     i'n'  —  in.     It  is      [5805i] 
useless  to  notice  other   terms,    in  which   these   coefficients   are  unequal  ;   because   they 
produce   nothing,  except    periodical    terms,  in   the   function   [5804];  as    is  evident    from      [5805c] 
[17]  Int. 

t  (3149)     The  complete  differential  of  the  first  member  of  158071       ^—.5     fndtl 

Indt        '  •'         y 

taken  relatively  to  the  characteristic     d ,     contains  the  two  terms  in   the  second   member      [5807aJ 

of  [.'>807]  ;  and   also  the  additional  term     —     „  "'  .  6  .  fndt  ;      but    this    term    contains 

the  three  factors     àR,     dn ,     5.  fndt;     each  of  which   is   of  the   order     m' ;     jience    it 

is  of  the  order     ro'^,     and  may  be  neglected  ;  and  the  expression  becomes  as  in  [5807].        [58076] 

J  (3150)     Taking  the  differentials  of  the  two  expressions  of    ^     [57  94],  and  dividing 
VOL.  III.  180 


718  APPENDIX,  BY  THE  AUTHOR;  [Méc.Cél. 

[5809]  d  A  —  .6  .fndt  I  =  3  an  .  -—- .  ffàR  .dt  +  Q  an  .  —  .  dt  -fàR  . 

We   may  unite,  in  one  expression,  all  the  terms  of  the  development  of    R  , 
which  depend  on  the  same  angle     i'n't  —  int,     and  it  becomes  of  the   form, 

[5810]  R  ^  k.  cos.(i'7i't  —  int  +  A)     [957'"]. 

Substituting  it  for    R,  in  the  functions      — r-  .ffàR.dl,    and    —  .  f  àR, 

it  LI  L  lid  V 

[5811]     we  find,  that  they  are  reduced  to  sines  of  double  the  angle*     i'n't  —  int+A; 

[5808a]     them   by     dt ,     we    get     n  =  3  fan.dR  ;  or,  as    it  maybe    written,     5n^=3fan.dR, 
as  in  [5S08].     Substituting  this  in  the  development  of    5. fndt,     we  easily  obtain, 

^ggjjgjj  Ô  .  fndt  =f5n .dt  =  3  ffan .dR.dt. 

These  values  being  introduced  into  the  second  member  of  [5S07],  we  get, 

r^Bna-i  d  .{  —  .5.  Cndi  >  =  — p-  .  3  fCan  .  dR  .  dt  4- —-  .  dt  .  3  fan  .  dR  . 

Each  of  the  two  terms  of  the  second  member  of  this  expression,  is    of  the   order     m'^; 
[5808rf]    and,  if  we  neglect  terms  of  the  order     m'*,     we  may  bring   the   factor     an,     from  under 
the  sign    /,     as  in  [5796rf — e]  ;  and  then  the  equation  [5808c],  becomes  as  in  [5809]. 

*  (31'51)     From     R  =  Tc.cos. {i'n't — int-\-A)    [5810],  we  easily  deduce  the  following 
[5810a]     expressions, 

J  p  If  7« 

[58106]               —  =  ¥i.s\n.{i'rJt — int-\-A)  ;  fdR  =  —  .,  i_.    .  cos.(iV< — int^A)  ; 

[5810c]       ffàR-dt  = J^^2  •  sin.(iW<— in<+^)  ;      7^  =  —  ^■î^n-oos.{i'n't—int-]rA)dt 

In  finding  these  expressions,  we  have  neglected  the  variations  of  the  elements   n,     n',    Sic, 
because  they  produce  only  terms  of  the  order     m'^     in  [5809].      The  product  of  the  two 
expressions  [5810c],  being  substituted  in  the  first  term  of  the  second  member  of  [5809], 
produces  a  term  depending  on, 
r5810d]  sm.{i!nt—int-\-A)  X  cos.{i'n't—int-\-A)  ^\.s\n.'2.{i'n't—int-\-A). 

In  like  manner,  the  product  of  the  two   expressions  [58106],  being   substituted   in   the 
second  term  of  [5809],  produces  another  terra  depending  on, 

jjgjO  ,  i.  sin.2.(iVî  —  int  -\-  A)  ,     as  in  [581 1]. 


VII.App.«§,2.]    TERMS,  IN  ^,  OF  THE  ORDER  »«^  mm,  m'm",  he.  719 

thus,  the  differential    d  .  (—-  .  i .  J'ndtj,  contains  only  jjeriodical  quantities.      [5811'] 

Hence  it  follows,  that     àJR,     contains  only  periodical  quantities,  tvhen  ive 

vary  in     Œ,     the  quantities  relative  to  the  planet  m  only.  "^       ^ 

To  obtain  the  complete  value  of    d.Œ,     tve  must  also  vary  in     ôR,     what 
relates  to  the  planet  m'.     For  this  purpose,  we  shall  put     R',     for  what    R      [58V3] 
becomes,  relative  to  the  planet  m',  disturbed  by  the  action  of  m.     We  shall 
then  have,* 

R'  =  "'•(^'''+yy+^--')_  ^  .  [5814^ 

r'  p 

hence, 

R^^  .R+m'.(xx'+yy'+zz').Ç-^^  -^)  .  ^^5815] 

The  variation  of  R,  so  far  as  it  depends  upon  the  variations  of  what 
relates  to  the  planet  m',  is,  therefore,  equal  to  the  variation  of  the  second 
member  of  the  equation  [5815],    arising  from  the   variations   of  the  co-      [5817] 


Symbol 


ordinales  of  m'.     We  shall  denote,  by     ô',     the  variations  which  correspond       à'. 


From  what  has  been  proved,  it  appears,  that  the  two  functions  [5806,  58 11 'J,  which  compose 

the  value  of    à.5R     [57967?],  produce  nothing  except  periodical  terms,  noticing  quantities     [5810/] 

relative  to     m,     as  in  [5812]. 

*  (3152)     Changing,  reciprocally,  the  elements   of  m  into  those  of  m',  we   shall  get, 

from     R     [5755],    the    expression    of     R'     [5814].      Multiplying    this    by     —,     we 

m 

obtain , 

m[  __  m'.(xx'\-yy'-\-zz') m^ 

m  '  t3  p    '  [5815a] 

subtracting  this  from  [5755] ,  we  get. 


R-^    R'^m'.^,X-+yy'+,,'y^±_^y, 


[5815 


from  which  we  easily  obtain     R     [5815].     This  expression  of    R     does  not  contain   p, 

and,  on  that  account,  it  is  more  convenient  than  the  expression  [5755],  in  making  the       [5815c] 

calculations  relative  to  ?«',  in  [5813 — 5831']. 


720  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.Cél. 

to  these  co-ordinates.     We  evidently  see,  by  the  preceding  analysis,  that,* 

is  composed  of  terms  of  the  form 

[5819]  M  ./Ndt  —  N  ./Mdt . 

To  obtain  their  differentials,  relative  to  the  characteristic     d,     we   must 

[5819]     vary  only  the  quantities  w^ithout  the  sign  of    integration  ;    because    the 

quantities  under  that  sign  correspond   to  the  elements  of  the  planet  m'.f 


*  (3153)  If  we  change,  in  [5795, 5796],  the  elements  ?^,  e,  a,  e,  zr,  p,  q, 
f5818a]  jj^j^  ^;^  ^,^  ^1^  ^^  ^1  ^  p/^  ^^  respectively,  we  shall  get,  by  using  the  characteristic 
[5818b]     i5',    as  in  [5817],  and  supposing    d'    to  affect  the  co-ordinates  of  m'  only  ; 

,e*,  ^J^=:i.!n/«'*)+<vs<S:).av+(f).,v+(t^)...,(f;).,y+(f,).V. 

i'R  =  ^^  .afn'dt)  I 

+  ^M(")->''"-(S')-(S)->''"-(f)J      , 

+  •^;KI')->--(f)-(?)->--Q|-         ' 

If  we  represent  by    /?/    the  four  lower  lines  of  the  second  member  of  this  last  equation, 
[5818e]      we  shall  get,  by  substitution  and  transposition,  the  following  expression,  which  is  similar  to 
[5796n] ; 

[5818/1  ô'R'-^^[.ô'ifn'dt)=R;; 

r58l8a-l     ^"^  ""^  ™^y  prove,  as  in  [5797^],  that  Rf  is  composed  of  terms  of  the  forms  mentioned 
in  [5819]. 

r5819a]         t  (3154)     The  terms  under  the  sign  of  integration,  in  the  second  member  of  [5818J], 


VII.  App.v^2.]  TERMS,  IN  ^,  OF  THE  ORDER  »«=,  mm',  mm",  &ic. 


721 


We    shall    suppose    these    two   corresponding   terms     of     M,     N,     to    be 
represented  by,* 

M=k.cos.(i'n't—mti'A)  ;  N  =  k!. cos. (i' n't— ini+ A').  [5820] 

Then,  we  must  combine  these  terms  together,  to  obtain  the  non-periodical 

quantities  in 

A.{M.fNdt—N.fMdt)  ;  [582i] 

and,   it   is  evident,   tliat    this  differential  function  does   not  contain   such 
quantities.     We  may  easily  prove,  that 

does  not  contain  any  ;  by  the  same  manner  of  reasoning  as  that  which  we 
have  used  in  proving  that 

cl.(L«.,.y„rf,)     [68ir] 

contains    only   periodical   quantities  ;  f     therefore,     à.ô' R     contains    only     [5821"] 
similar  quantities. 


arise  from  the  quantities     o'/,     à' a,     h'e',     (5'ra',     o'p'     h'q^,     à'  .fn'dt;     which  contain 
terms    with    the  sign    /,     like  the  similar   expressions  of     àe,     Sa,     &;c.    [5796rf — k].     rsgigj-i 
Now,   these  quantities     oV.     ô'a,     Sjc,  depend   on  the  co-ordinates  of  the  planet    m'  ; 
therefore,  their  differentials  relative  to     d     [5785]  must  vanish.     On  the  contrary,  the 

factors    — -,      {~T-)'      (  TT  )'     Sic,  in  the  function  [5818c],  may  produce,  in  [5818rf],      r58i9e] 

some  terms  without  the  sign    /,     containing  the  elements  of  the  planet    ?n,  which  will  be 
affected  by  the  differential    d. 

*  (.3155)     The  calculation  in  [5819—5821"],  is  similar  to  that  in  [5800—5812]  ;  and 
the  functions  [5800,  5801,  .580.3,  &c.],  correspond,  respectively,  to  [.5819,5820,5821,  &c.]  ; 
hence  we  obtain  a  result,  similar  to  that  in  [5806]  ;  namely,  that  the  differential     d  ,     of    [53206! 
the  function  [5818/"],  does  not  contain  non-periodical  quantities. 

t     (3156)     If  we  develop  the  function  [5821'],  we  shall  get,  by  observing,   that     n, 
and    fn'dt,     are  not  affected  by     d  ; 

VOL.  III.  181 


722  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

It  now  remains  to  consider  the  second  term  of     R     [5815],  which  we 
shall  denote  by, 

[5822]  p  =  m'.  (.r.;'+^y  +  r=')  .  (^-^3)  • 

We  have,  as  in  [915],* 


We   may  substitute,  in   the   second  member  of  this  equation,  for     b' .[fn'dt),     its    value 
[5821fe]    fb'n'.fh;     and,    for     ô'n',     its  value     &'n  =3ftt'n.d'R',     which  is  similar  to   [5S08]  ; 
hence  we  shall  have, 

[5821C1  d  .  S  ^-^'.&'.{ fn'dt)  1  =  ^,-  .  3//a'n'.  à'R'.  dt  =  ^.3  «'«'.  ffà'R.  dt  ; 

'-  ■"  (  ndt  )  n'dt         •'•'  n'dt  '  '' 

observing,  that  we  may  bring     an      from  under  the  sign    ff,    by  neglecting  terms  of  the 
order  m^,  as  in  [5796e,  Stc.].     Now,  if  we  put 

[5821rf]  R'  =  'k.cos.{i'n't  —  int  +  A), 

we  shall  get,  in  like  manner  as  in  [5810c]  ; 

k  i'n'  AA'R 

r5821f]  rCA'R'.dt  ==  — '- .  sm.{i'n't—ini+A)  ;      --,  =  Jc.i'i7i.cos.(i'n't — int-\-A)uc- 

The  product  of  these  two  quantities  being  substituted  in  the  last  expression  of  [5821c], 

r5821/"1     produces  only  a  periodical  term  depending  on     s\n.2. (i'n't — int-\-A)  ;     in  like  manner  as 

in  [5810<?,  Sic.].    Having  found,  that  the  differential  relative  to  d,  of  the  function  [5818/], 

and  that  of  [58:21'],  produce  only  periodical  quantities;  their  sum   representing  the  value 

[5821g-]    of    d.S'R',    deduced  from     5'R'     [58 IS/],  must  also  consist  of  such  periodical  quantities; 

r5821?i]     which  may  be  neglected  :    therefore,  we  may  reject  the  term     —  .  R',     in    the  value  of 

R    [5815],  and  it  will  be  reduced  to     R  ^^  P;     using  the  abridged  symbol    P   [5822]. 

*  (3157')     Substitutine,  in  the  first  of  the  equations  [915],  the  value  of    M4-m  =u. 
[58230]  , 

^  [914'],  we  get, 


ddx  ,  {M-\-m).x  ,  /dR\ 
[58236]  ^  =  -^2 


{M+m).x      /dR\  Mx ddx       mx       /dR\ 

multiplying  this  by     —,     we  obtain  [5823].      The  second   and  third  of  the  equations 

r58''3cl     [915],  give  smndar  expressions  01     —,     — .     It,  in  these   equations,   we  change     m, 
X,    y,    z,  r,     into     m',   x',    y',   z',    r',  respectively,  and  the  contrary  ;  and,  then  multiply 

"''  !•  1  <■        ^'■'■'       ^y'       "'*'       mi 

r5823(il    ^J     ~'     ^^'^   ^'^^^'   §^^  ^^^  corresponding  values  of    —7^,    —,    — .    The  first  of  these 
expressions  is  explicitly  given,  in  [5825]. 


vu.  App.§-2.]  TERMS,  IN  ^,     OF  THE  ORDER  m^  mm',  rn'm",  he. 


723 


m'x  m'      (hlx        mm!  x         m'     /dR\    _  [58231 

M    being  the  sun's  mass.     We  have  also,  [5824] 

m'x'  m'      ddx'        m'"       v'  in'     /^dR'\  [58251 


r'3  M  '    dt^        M  '   r'3         M'  \dx' J 

The   co-ordinates     y,     z,     y',     z',     ^Jroduce   similar  equations  ;  hence  we 
easily  deduce,* 

m'      d.{x'dx—xdx'-\-y'dy—ydy'-\-z'dz—zdz')        ^ 

Q      being   a  function   of    x,     y,     z,     x',     y',     z',     of   the    order   of   the      [5827] 
square   of  the  masses    m,    m'     [5825c,  c"].     The  variation    of  the  part  of 
P    [5826],  which  is    independent  of     Q,     may  be  expressed  by, 

™'      d.6'.{x'dx-Tdx'+y'dy-ydy'+z'dz-zdz')   _ 
^~M'  dfi 


*  (3158)     The  terms  depending  on     x,     x',    in  [5822],  are     'iLfl.  _  ^^  .      The     [5825a] 

value  of  this  function  is  found,  by  multiplying   [5323]  by     — x',     also    [5825]  by     -j-'^) 
and  then  taking  the  sum  of  the  products.     Hence  we  have, 


m'.xx'        m'.xx        m'      (x'ddx — xddx')       m'.xx'     C  m       m' 
~7^  ^ ^ M ■  ~d^  ^    M    '  }?~'7^ 


^M     I         \dxj  \dx'J 


[58256] 


If  we  substitute,  in  the  first  term   of  the   second   member,  for     x'ddx — xddx',     its   value 
d.(x'dx — xdx')  ;  which  is  easily  proved  to  be  identical,  by  development  ;  and  put    ^,     for  •' 

the  remaining  terms  of  the  second   member,  which   are  of  the  order     m^;     we   get   the 
expression    [5825rf].     The    similar   expressions   in     y,     y' ,      z,     z',     give  [58256,/]  ;     ^  ' 

Q,n     Qa)     being  quantities  similar  to      Q, ,     and  of  the  order     m^.     The   sum    of  the 
equations  [5825(7,  e,/],  being  substituted  in  [5822],  putting     Q  =  Q,-f  Q,H- Q, ,    becomes     [S825c"] 
as  in  [5826]  ; 

m'      d.{x'dx-xdx')^^^^  ^5g25rf] 


m'.xx'. { 

f  1          1 
Vr'3        r3 

r  1       1 

m.yy'.[ 

Vr"       7-3 

(  1           1 

■ni.  rz'.l 

\r^       ,.3 

M  df 

m^      d.(y'dy—ydy') 
M  '  dt"" 


+  Q»  ;  [5825e] 


to'      d.(z'dz — zdz') 

M  • d? ^  ^'  '  f^^^^-^] 


724 


APPENDIX,  BY  THE  AUTHOR  ; 


[Méc.  Cél 


[5829] 


[5830] 


and,  as  this  is  an  exact  differential,  we   shall  obtain   the   part  of    fà.ô'P, 


which  depends  on  the  function  [5828],  by  changing,  in  this  function,  d  into 
[5829']     d   [5829e]  ;*  and  then,  it  is  evident,  that  it  contains,  in  terms  of  the  order 
m^    none  but  periodical  quantities   [5829î]. 


The   term     Q     will  give,  in    fdP  ,     the  quantity    fàQ .     If  we  notice 


rggoQ-,         *  (3159)     If  We  neglect,  for  a  moment,  the  consideration  of  the  quantity      Q,     the 

remaining  part  of  the  second  member  of  [58'26]  will  be  an  exact  differential,  which  we 

'■    _      •'     shall  represent  by     dP,;     so  that  we  shall  have     P  =  dP^.     Its  variation,  relative  to  i5', 

[5829c]     gives  ô'P  =  d.S'P,,  which  corresponds  to  [5828].     Integrating  this,  we  get  fi'P  =  è'P;, 

and  its  differential,  relative  to  the  characteristic    d,     gives    y"d.(5'P=d.f5'P,.     Comparing 

'•  ^     this   with     li'P     [5829c],    we  easily   perceive,    that    fà.ô'P     can  be  deduced  from  this 

[5829e]     expression  of    '5'P     [5S29c,  or  5828],  by  changing,  in  its  second  member,     d     into     d, 

as  in  [5829']  ;  hence  we  shall  have. 


[5829/] 


m'      à.&'.{x'dx-xdx'+y'dy-ydy'+z'dz 


idz') 


dt^ 


[5829-] 
[5829A] 

[5829i] 

[5829A;] 

[5829i] 
[5829m] 

[5829n] 
[5829o] 


If  tlie  function     —-Ax'dx — xdx'-\-y'dy — ydy'-\-z'dz — zdz'\,     by  the  substitution  of  the 
at 

elliptical  values  of  r,  y,  z,  x' ,  y',  z',  produces  a  term  represented  by  A^  ;  its 
variation,  relative  to  h',  will  become  (5'^,  ;  which  is  of  the  first  order  relative  to  the 
masses,  as  is  evident  from  the  import  of  5'  [5817]  ;  and,  when  à'A^  is  multiplied, 
as  in   [5829/],  by     —,     it  becomes  of  the  «cconrf  order.     This  is  finally  reduced  to  the 

third  order,  in  the  second  member  of  [5829/],  by  taking  the  differential  relative  to  d,  of 
the  non-periodical  terms  ;  because  it  produces  the  differentials  of  the  elements  [5786, 8ic.], 
which  are  of  the /rs<  order.  Hence  it  appears,  that,  if  we  neglect  the  non-periodical 
terms  of  the  third  order,  relative  to  the  masses,  we  may  put  the  part  of  fà.à'P,  which 
depends  on  the  function  [5828],  equal  to  nothing.  Then,  there  will  remain  to  be  noticed 
only  the  part  of  the  function  fà.i'P,  depending  on  Q  [5829o]  ;  which  may  be 
represented  by  fd.S'P  =/d.<5'Q.  But,  q  is  of  the  order  m^  [5827],  and,  if  we 
represent  it  by  m^A„,  we  shall  have  6'Q,  of  the  order  m^.è'A^;  which  is  of  the 
third  order  relative  to  the  masses,  as  is  evident  from  [5829Â]  :  therefore,  it  may  be 
neglected.  What  is  proved  in  [5814 — 58.31],  relative  to  the  planet  ?«',  may  also  be 
applied  to  the  other  planets  m",  in!",  &ic.;  but,  it  will  still  be  necessary  to  notice  the  effect 
of  m"  on  m'  ;  m"'  on  m',  Sic.  ;  m!"  on  m",  h.c.  ;  in  the  value  of  R.  This  is  done  in 
[5833,  &tc.]. 


VlI.App.§-2.]         TERMS,  IN  ^,  OF  THE  ORDER  m^,  »»«',  m'm",  he.  72Ô 

only  terms  of  the  Older     m"     in     dQ,     it  will  sufrice  to  substitute  in     Q, 
the  elliptical  values  of  the  co-ordinates,  and  then    fdQ     will  contain   only 
periodical  inequalities.     Thus,   J'd.oP,     will  contain  only  similar  quantities.      [5t3l] 
Hence    it    follows,  that    fd.&R     will    contain,  in    terms   of  the  order     mr, 
only  periodical  quantities,  when   we  vary  in     R,     the   co-ordinates  of  the      [5^31] 
two  jjlanets     m     and     m'. 

If  there  be  a  third  planci     m",     it  adds  to     R     the  function* 

p'  being  the  distance  from  in"  to  m.  The  part  of  R,  relative  to  the 
action  of  m  upon  m,  then  acquires  a  variation  depending  on  the 
action  of     m"     upon     m'.     This  part  of     R     is, 

„        m'.(xx'+yy'+zz')        m'     rrirr. 

K^    ^^ —^ [OlOO\    ;  [Aclionof    m'    on     m]  [5833] 


the  variation  of  the  co-ordinates  x',  y\  z',  by  the  action  of  m",  produces 
in  [5833],  some  terms,  multiplied  by  rn'm",  which  are  functions  of  the 
elliptical  co-ordinates     x,     y,     z,     and  of     the  angles     n't,     /t'7  .f     But 


[5834] 


*  (3160)     The  expression  [5832]  is  the  same  as  [Ô755];  changing  the   elements  of 
m      into  those  of     ni".     It  corresponds  to  the  second  terms  in  the  expressions  of    R,     X     15832a] 
[913,914]. 

t  (3161)     The  co-ordinates     x',     y',     z'.     contain  the   elliptical  values   of  the  orbit 
of    m',     augmented  by  the  terms  arising  from   the   action  of  the  bodies     ?«,     m" ,     m'",    [5834a] 
&ic.     When  these  are  substituted  in  [5833],  they  produce  terms  of  the  second  order  of  the 
masses,  which  we  shall  represent   by     tn'm"A^;    A^     containing  among  other  terms,  the 
quantities     x,     y,     z.     The  co-ordinates  of  the  planets     m',     m",     which  occur  in     A  ,     [58346] 
introduce  the  angles     n't,     n"t     [5834,950,952,953],  and  the  co-ordinates     x,     y,     z, 
contain  the  angle     nt .     The  products  of  the  sines  and   cosines  of  such   angles,  produce, 
in  AR,  some  terms,  which  depend  on  the  angles  int-{-i'n't-\-i"n't   [1214'"]  ;  and,  as  n,  n',     t^^'^^e] 
?i"     are  incommensurable  [1197"],  these  terms  will  be  periodical.     Therefore,  by  noticing 
only  the  non-periodical  terms,  in     dR ,     we  must  consider     i',     i"     as  equal  to  nothing  ;    t^^^^''] 
or,  in  other  words,  we  must  notice  in     R,     only  those  terms  which   are   independent   of 
n't,     n"t,     as  in  [5835],  and  then  it  becomes  of  the  form     m'm"X     [5836];     X     being 
a  function  of  the  co-ordinates  of    m,     as  in  [5836].     Putting  this  equal  to     R,     it  gives     t5834e] 

VOL.  III.  182 


726  APPEiVDlX,  BY  THE  AUTHOR;  [Méc.  Cél. 

._„„.,  these  angles  must  vanish  from  the  non-periodical  part  of  dR,  and  as  they 
cannot  be  destroyed  by  the  angle  nt ,  which  is  introduced  by  means  of 
the  values  of  x,  y,  z;  we  need  only  notice,  in  the  development  of  the 
variation     R,     the  terms  which  are  indejjendent  of     n't     and     n"t .     These 

[5836]  terms  will  be  of  the  form  m''m"X;  X  being  a  function  of  the  co-ordinates 
of  the  planet  m,  they  introduce  into  fdR  some  terms  of  the  form,  m'm".fdX, 
or  m'm"X\  which  produce  only  non-periodical  quantities  of  the  order 
m'ml'\     and  such  quantities  we  have  neglected  in    fdR. 


[5838] 


In  like  manner,  the  variation  of  the  co-ordinates  x,  y,  z,  by  the 
action  of  m",  can  introduce  in  the  preceding  part  of  R  [5833],  only 
the  angles    nt     and     n"t;     therefore,  we  need   only   consider,  in  this  part, 

[5839]  the  terms  independent  of  7i't ,  consequently  of  the  form  m'm"X;  X 
being  a  function  of  the  co-ordinates     x,     y,     z,     only;  which,  as  we  have 

[5840]  just  seen,  can  only  produce  quantities  that  may  be  neglected.  Thus,  by 
noticing  only  the  non-periodical  quantities,  of  the  order  m^  in  fdR, 
we  may  suppose,  that  in"  is  nothing,  when  we  consider  the  part  of  R , 
relative  to  the  action  of     m!     upon     m  ;    and  we  may  suppose    m'   nothing, 

[5841]  when  we  consider  the  part  of  R  relative  to  the  action  of  m"  upon  m,'. 
we  have  just  seen,  that  in  these  two  cases  [5837, 5840],  the  secular 
variation  of  fdR    is  nothing.     This  variation  is,  therefore,  generally  nothing, 

[5842]  when  we  consider  the  reciprocal  action  of  three,  or  of  any  number  of  planets, 
if  we  only  notice  as  far  as  the  squares  and  products  of  the  disturbing  forces, 
inclusively,  in  the  value  of    dR. 

We  shall  now  resume  the  equation  [5794], 
[5843]  2,  =  3ffa.ndt.dR. 

Its  variation  is,* 


[5834/]  àR  =  m'm'.dX;  whence  fdR  =  m'm" .fdX  =  m'm"X ;  this  last  expression  being 
deduced  from  that  which  precedes  it,  by  omitting  the  double  sign  /d,  taking  into 
consideration,  that     X     is    a    function    of  the   co-ordinates  of    m     only,  as    in  [5836]; 

[5834ff]  consequently  the  signs  /d  represent  inverse  operations  which  mutually  cancel  each 
other.  The  variation  of  the  expression  fdR  =  m'm"X ,  produces  in  fd.SR  ,  non- 
periodical  quantities,  of  the  third  order  of  the  masses     m,     in',    he,  which  are  neglected. 

[5844o]        *  (3162)     Multiplying     an=a-i     [57516]    by     dR,     we   get     an.dR=a-KdR 


VII.  App.s^-2.]        TERMS,  IN  ^,  OF  THE  ORDER  m«,  mm',  m'm",  he. 


727 


6P  =  3(1)1.  ffdtA.6R+3a-.ff(ndLdR.fdR). 

We  have  just  seen  [5812,  5821",  &c.],  that  d.o/t  is  nothing,  noticing  only  the 
secular  quantities,  as  far  as  the  order  of  the  square  of  the  masses  of  the  planets, 
inclusively.  We  have  seen,  likewise,  that  dR  .fdR  is  nothing,*  noticing 
only  the  same  quantities.  Therefore,  if  we  take  into  consideration  only  the 
secular  quantities,  which  acquire,  by  the  double  integration,  a  denominator  of 
the  order  of  the  square  of  the  masses  of  the  planets  ;  we  shall  find,  that  the 
valuation  5^  vanishes.  Hence  it  is  manifest,  that,  if  we  notice  the  secular, 
as  well  as  the  periodical  quantities,  this  variation  cannot  exceed  a  term  of  the 
order  of  the  disturbing  masses.f  This  important  result  ivas first  obtained  by 
Mr.  Poisso7i. 


[5844] 


[5845] 


[5840] 


Importent 
ipsnll,  by 
M. Poisson. 


[584C'] 


Taking  its  variation,  and  then  substituting   tlie  value  of    Sa     [5196d],  also     a~- =  (ni,     [5844a'] 
a'=  a^ii,     we  get,  successively,  by  neglecting  terms  of  the  order    m^  , 

S.{an.dR)  :^  o.(a~- .  dR)  =  a~^.  d.SR  —i.a~K dR.Sa  =  an.d.Œ -{-a^ n.dR  .fdR.  [58446] 

Multiplying  this  by     3f/^     and  prefixing  to  the  double  sign    ff,     we  obtain. 


^^, 


3  5.ff{an,dR)=Smi.ffc1t.d.ôR+3a^-.ff^ndt.dR.fdR)  ;  L^^^''^] 

the   terms     an,     a^,     being    placed    without   the   signs    Jf;     which    can  be    done,  by 
neglecting  terms  of  the    order     ?«',     as  in  [5796c,  &:c.].     Now,  taking  the   variation     &     [5844rf] 
of    ^     [5S43],  and  substituting  [5844c],  we  get  [5844]. 

*   (3163)     We  have  seen,  in  [5810e],that  the  product  of  the  two  equations  [5810i], 
which  represents  the  value    of    —.dRfdR,     produces  only  periodical  inequalities,  as     [5845a] 
in  [5845]. 

t  (3164)     The  elements  of  the  orbit  of  a  planet  are  represented  in  [1102, 1133],  by 
systems  of  terms  of  the  forms, 

N.sm.{gt  +  ^)    ;  N.  COS.  (gt+fi)   ;  [5846a1 

in  which     g     is  of  the  same  order  as  that  of  the  disturbing  masses   m',  m",  kc.  [1097c]. 

The  double  integration  of  a  quantity,  depending  on  an  angle   of  this  kind,  in  [5843  &.C.],      [58466] 

introduces,  into    i^  or  «5^,   the  divisor    g^,     of  the  second  order  of  the  disturbing  masses. 

But,  the   terms  of  the  Jîrsi  and  second  orders,  vanish   from   the  expressions  in  [5845]  ; 

therefore,  this  divisor  can  operate  only  upon  those  of  the  third  or  higher  orders  ;  and,  when      [5846c] 

those  of  the  third  order  ot'^   are  divided  by  g^,  they  produce  terms  of  the  first  order  only; 


728  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Ctl. 

3.      We  shall   now  consider  two  planets  m  and  m',  i7i  motion  about  the 

[5847]     sun,  ivliose  mass  we  shall  take  for  unity.     We  shall  put     v    for  the  angular 

g.g,     distance   of  the  planet  m,  from   the  line  of  intersection  of  the  tîvo  orbits  ; 

v'  for  tlie  angular  distance  of  the  planet  m',  from  the  same  right  line  ;  also 

[5849]     Y  for  the  mutual  inclination  of  the  tivo  orbits  ;  taking  the  orbit  of  m  for  the 

[5850]     plane  of  the  co-ordinates,  and  the   line  of  the  nodes  of  the  orbit,  for    the 

origin  of  x;    ice  shall  have,* 

X  =  r.cos.»  ;         y  =  r.sin.iJ  ;  r  =3  0  ;  1 

[5851] 

x'=  r'.  cos.v'  ;        y'  =  r.  cos.}  .sin. r'  ;    z'  =  r'.  sin. 7. sin. «'  ;  2 

which  gives,  by  putting,! 


r5846rfl  *^'"'  ^f  ^^*  same  order  as  the  peiiodical  inequalities.  This  agrees  with  [5846']  ;  and,  the 
importance  of  this  result  of  Mr.    Poisson,  is  manifest  from  the  consideration,  that,  if  the 

r5846  1  ^^'"'^s  ^^  the  second  order,  relative  to  the  masses,  instead  of  vanishing,  as  in  [5846],  were, 
on  the  contrary,  of  their  usual  magnitude,  or  of  the  order     m'^,     they  would  produce,  in 

[5846/]     ^    [5843],  by  the  double  integrations,  terms  of  the  order     —^  ,     or  of    di  finite   order  ; 

[5846g-]     which  might  become  sensible,  in  the  theory  of  the  planetary  motions. 

*  (3165)  The  formulas  [5851],  are  as  in  [3740,  3740'],  changing  the  value  of  7, 
[5851a]     which  represents,  in  [3739,  Sic],  the  tangent  of  the  inclination  of  the  two  orbits  ;  but,    7 

1  y 

is  used  for  the  inclination  itself  in  [5849]  ;   so  that,  we  must  change         /    ,     „  ,  , 

[58514]  I  J.  >  5        v/j+7-  \/l+>2 

[3740c],    into     cos. 7,     sin.7,  respectively  ;     by  this  means,     y' ,     z'     [3740'],  become 
as  in  [5851, line  2]. 

t  (3166)  Substituting  the  values  of  x,  x',  &c.  [5851],  in  the  first  member  ol 
[5853o]     [58536],  it  becomes  as  in  its  second  member.     Putting,  in  this,     cos.7  ^  1 — p     [5852] 

and  successively  reducing,  we  obtain  [5853c?].  In  like  manner,  by  developing  the  first 
[5853a']     member  of  [5853e],  and  substituting     x^-\-y^-\-z^  =^  r'^  ;     x'^-\-y'^-{-z'^  ^ /^     [3742d]; 

we  get   [5853e,/]  ; 

[58536]  *^*'+yi/'-|-*'2^'  =  '■?"'. {cos. v.cos.î)'-|-cos. 7. sin. î>. sin. î)'| 

[5853cl  =  rr'.5cos.2;.cos.t)'-)-sin.D.sin.T' — p.sin.r.sin.ii'l 

[-5353^^  =  rr'.\cos.{v'—v)—^.sin.v.sm.v'\  ; 

[5853e]        {x'-xY+iy'-yYM^'-^y  =  {x^+y'+z^)-^{œ'^+y'^+z")-^.{ix'+yy'+zz') 
[5853/]  =  r^-\-r'  ^ — 2rr'.  cos.(«)' — v)-\-2^.rr'.  sin.v.sin.»'. 


VII.App.§3.]  DEVELOPMENT  OF  R.  729 


R 


/3  =  1— COS.;.  =  2.sin.''^7  ;  [5852] 

m'.  (xx'-j-yif-^-zz')  m! 

''  7^  ~~  \/(x'—  xf  +  {y-—yf  +  (z'— z? 


[5853] 

ot'.  r  m' 

=  — r-4cos.(i''-îj)-(3.sin.u.siiw'? —  /  „     „  ^    ,  ,     ^  ^ ^,  .    -;2        r. 

r'^  \/r+r' -2rr.cos(?)-t;)+2^.rr.sin«.sin.ij' 

under   this  form,     R     becomes  independent  of  the  plane  to  which  the  co-      rro-.n 

ordinales  are  referred  [5853o-].    Developing  it,  in  terms  of  sines  and  cosines 

of  angles,    increasing  in   proportion  to  the  time    t,    by  the  substitution  of 

the  elliptical  values  of     r,     r',     v,     v'     [952,  953],  it  becomes  a  function 

of  the   mean  angular  distances     nt-\-s,     7i't-\-s',     of  the  planets,  from  the 

line   of  nodes  ;    of  the  distances   of  the  perihelia  from  the  same  line  ;  of 

the  semi-axes     a,     a'  ;     of  the  excentricities     e,     e'  ;  and  of     p,     or  the 

mutual  inclination  of  the  orbits  :     (3     being  a  very  small  quantity,  of  the 

order  of  the  square  of  that  inclination  [5852].     Under  this  form,     R     does      [5856] 

not  contain    explicitly  the   variable    quantities     p     and     q     [1032]  ;    but, 

we  may  introduce  them  in  the  following  manner. 


Substituting  [5853(Z,/]  in  [5755,  or  5853 line  1],  we  get  the  expression  in  [5853  line  2]  ; 
which  is  a  function  of  v,  v' ,  p  [5852]  ;  and  these  quantities  depend  entirely  on  the 
relative  position  of  the  two  orbits,  and  are  wholly  independent  of  any  arbitrary  plane,  to 
which  the  co-ordinates  can  be  referred  ;  as  in  [5854]. 


[5855] 


[5857] 


Instead  of  referring  the  motions  of  the  planets  to  their  orbits,  we  may 
refer  them  to  the  fixed  plane  of  the  primitive  orbit  of  m  ;  then  z  will 
not  vanish,  and  it  will  be  represented  by  z^r*;*  s  being  the  sine  of  [5858] 
the  latitude  of  m,  above  that  plane.  If  we  neglect  the  square  of  the 
disturbing  forces,  we  may  reject  the  square  of  s  ;  then  we  shall  have, 
instead  of    R,     the  following  function,  which  we  shall  denote  by,t 


[5859] 


[5853^-] 


*  (3167)     This  is   similar    to     [3787],     z     being    the    perpendicular,  and     r     the 
hypothenuse  of  a  right-angled  plane  triangle,   of   which   the   sine  of  the  angle  at  the     [5858a] 
base  is     s. 

t  (3168)     If  we  use     z  =  rs     [5858],  and     z'     [5851  line  2],  we  get, 

zz  =  rr'.s  .sm.y.s'm.v' ,     instead  of    zz^O     [5851];  [5859al 

VOL.  III.  183 


730  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 


[5860] 


R  =z  — ;^.^cos.(t;' — v) — |'3.sin.?;.sin.îj'+s.sin.7.sin.î;'}  1 


R.  —  — .         2 

i/r^+Z- — 2rr'.cos.(«' — v)-\-'2.^.rr'  .sm.v.s\n.v' — 2rr'.5.sin./.sin.?;' 

rsSGi]  In  these  values  of  R  and  H,  we  shall  subtract,  from  v,  v',  the 
longitude  è'  of  the  node  of  the  orbit  of  m'  upon  m  ;  this  longitude 
being  counted  in  the  orbit  of    ?«.     This   is  equivalent  to  a  change   in   the 

[5862]      Qj-ig{ji  Qj'    ^     and     v'  ;     and  we  shall  suppose,* 


[5863] 


[58596] 


[5859c] 


[5859rf] 


S  =  q.sm.(v  —  ê')  —  j?. COS. (27  —  è') . 
Then  we  shall  have,t 

hence  the  value  of  x  x' -{•  y y' -\- z z'  [5Q53d]  must  be  increased  by  that  quantity  ; 
moreover,  the  value  of  («'— a:)^  +  (y~2/)-  +  (2'' — z)'^  [5853/],  which  contains 
—  2 .  {x  x'-{-y  y'-\-zz'},  must  be,  for  the  same  reason,  augmented  by  the  term 
— arr'.s.sin.y. sin.î)';  and  these  corrections  being  applied  to  the  corresponding  terms  of 
[5853  hne  2],  it  becomes  as  in  [5860];  observing,  that  the  value  of  y=r.sm.v 
[5851  hne  1],  may  be  retained  in  this  hypothesis,  if  we  neglect  quantities  of  the  order  s^. 
For,  the  correct  value  of    y,     being  similar  to  that  of    y'     [5851]  ;  namely, 

y^r. COS.7,. sin.u  =?•.  sln.i; — r. sin.i;.(2.sin.|7y)^  ; 

7,    being  of  the  order     s,     we  may,  by  neglecting    s^,     suppose 

yz^r.s'm.v,     as  in  [5851  line  1]. 


*  3169)  The  expression  [5S63],  is  like  that  in  [1335'],  altering  the  origin  of  the 
angles  v,  by  writing  v—ê'  for  v,  as  in  [5861].  We  may  remark,  that  the  angle 
^ — Ô'  is  counted,  as  in  [3739],  from  the  line  of  nodes,  or  mutual  intersection  of  the 
[58626]  Qj.(3-ug^  Q,j  ff^g  ^^jj^  of  m  ;  and  the  angle  v' — &'  is  counted  from  the  same  line  of 
nodes,  on  the  orbit  of  m  ;  so  that  we  may  consider  the  origin  of  the  angle  v  to  be 
on  the  orbit  of  m,  at  a  point,  which  is  distant,  by  the  angle  è',  from  the  node,  and 
counted  upon  the  orbit  of  m.  In  like  manner,  the  origin  of  the  angle  v'  is  taken  ujion 
the  ^;Zane  of  the  orbit  of  m',  and  at  the  same  distance  é'  from  the  node,  but  counted 
on  the  orbit  of  m'.  This  is  evident  from  the  investigation,  in  [3737 — 3740'],  of  the 
formulas  [3740,3740'],  which  are  similar  to  those  in  [5851]. 

t  (3170)     If  we  decrease  the  angles     v,     v      by     è',     as  in   [5S6I],  we   shall  find, 
that  the  angle     v' — v     is  not  altered  ;  but  the  expression     sin.u.sin.î)'     becomes, 

[5864a]  sin.  (.-n.  sin.  (.'-O; 


[5862c] 
[5862d] 


VII.App.>^3.]  DEVELOPMENT  OF  iî.  731 


R  =  ^2  -\(l—hr^)-cos.(v'—v)+ir^.cos.(v'+v—2è')\  1 

2 


m' 


[5864] 


[5865] 


V//-2+7-'2— 2;t'.|(]— ip).cos.(t)'— «)+ip.cos.(î;'4-r— 2ô')[  ' 

^_n^r  S  (1— èP+è'/-sin.7).cos.(îj'— «)+(ip— i9.sin.7).cos.(î)'+tJ— 20  )    1 
'"'"     (  — |p.sin.7'.sin.(i'' — v) — ^.s\n.y,s'm.(v'+v — 2t)')  )  2 

m/ 3 

y  y/ ^■2tj.'2_2j.r'     5  (1— à(3  +  à?.sin.>).cos.(«'— w)+(.lp  — a?.sin.>).cos.(«'+r  — 2d')  )  . ^ 
V'  (.  — èp.siii.>.sin.(«' — j>) — ip.s\a.y.sm.{v'-]-v  —  2^')  ) 

now,  it  is  evident,  that  we  may  change     R     into     R,     if    we  vary  in     R, 

(3     by     ^|3;     v     by     Sv;     and     ô'     by     (5()'     [5867^■],•  so  that  we  may  have,*      L5866] 

5/3  =  —  ç.sin.7  ;  1 

(l_i|3).5|j  =  cos.^ir.'5v  =  —  ip.sin.7  ;  2      ^ggg^^ 

p.(5a' — 1|3.5d  =  —  i^.sin.7.  3 


which  may  be  reduced  to, 

Jcos.(2;'-z;)— Jcos.  («'+!>  -2  r)     [17]  Int.  ^^^^^^ 

Substituting  these  in  [5853 line 2],  we  get  [5S64].     Now  if  we   multiply   the   expression 
[5S63],  by    sin.7.sin.(v' — ê'),    and  reduce  the  product,  by  means  of  [17, 18]  Int.,  we  get, 

C  |7.cos.(i'' — v) —  ^q  .cos.(u'+ w  —  2()')  — ip.sin.(v' — v)  > 
i.sin.7.sin.(!;' — ^')  =  sm.y .  ^  "  / . 

(  — ^p.s'm.(v'-\- V  —  2ê')  \' 

Substituting,   in    [5860],  for     sin.tJ.sin.t)',     its  value  [58645]  ;  and  for     s.sin.7.sin.'i;',     its 
value  [5S64c],  we  obtain  [5865]. 

*   (3171)     If  we  put  the  factor  of    -7^     'i    [5864  line  1],  equal  to     w;     and  that  of 
[5865]  equal  to     w  -|-i5w  ;     we  shall  have, 

w  =  {l  —  lfi).cos.(v'—v)-\-y.cos.(v'-}-v—2è')  ;  [58676] 

ow  =  55r.sin.7.cos.(«;' — v)  —  5p.sin.7.sin.(r' — v)  —  i9'.sin.7.cos.(î>'+î^  —  2^') 

~      .         .    ,     ,  s  [5867cl 

—  ip.sm.y.sm.[v-\-v  —  2ê')  . 

Then     72     [5864],  being  considered  as  a  function  of    w  ;     that  of    R     [5865],  will  be  a 

[5867c'] 
similar  function  of    w-{-5w.     Now,  if  we  take  the  variations  of    w     [58675],  considering 

p,     V,     ê',     as  variable,  and  neglect  the  second  and  higher   powers  and  products   of    5/3, 


[5864c] 


1 5867a 1 


732  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.Cél. 

Thus  we  get, 

,  .  /dR\ 

\dv  J         sm.y'\dà'J' 


ri  r.  •  /'<iR\  ,         /'dR\  V         fdll\ 

[5868]  R=R-  q.sm.r  .  ^-)  -p.Ung.h7  •  (,-)  -  £^  •  (^-^  '- 


and  we  have,  as  in  [5163/], 

/dR\         dR    ,    ^dR\ 

This  being  premised,  the  equations   [5790,5791]   give*  the   two  following 

5v,     èê',     we  get, 

èw  =  —  ^5^.cos.{v' —v) -{- {]  —  ^^).Sv.s\n.{v'—v)  -f-  l&^.cos.{v'-\-v — 2è') 
[5867d]  +  {^.èé'—U.5v).sin.{v'+v  —  2ê')  . 

Comparing  the  coefficients  of    cos.(c' — v),     sin.(D'— î;)     &,c.,  in  the   expressions  of    i5vv 
[5867c,  rf],  we  obtain, 

rcQ^-  1  —  Pp  =  Iq.sin.y  ;     (1  —  ip).(5«  =  —  ip.sin.7  ;     (3.5(3'—  ip.5v  =  —  \p.un.y  . 

\pOXHt\ 

These  equations  agree  with  those  in  [5S67]  ;  observing,  in  [5867  line  2, 5852],  that  we 
[5867/]  have  1 — Jp  =  1— sin.^ly  =  cos.^^y.  If  we  substitute  sin.y  =:  2.sin4y-cos.Jy  [31] 
[586~ê-]  Int.,  in  [5867nne2],  and  divide  the  result  by  cos.^^y,  we  get  5v  == — jp.tang.^y. 
[5867fi-'l    Subtracting  the  equation  [5867  line  2],  from  that  in  [5867  line  3],  we  get,    ^M —  èv  =  0, 

hence, 

,,.._,,  U'-^I=-P:^^^^^^ V- =_^i^      [5867^,5852]. 

[5867A]  ^^  —  ^  2.sin.2^y  a.sin.J-y.cos.^y  sin.y      •■  ^'  ^ 

It    is   evident,  by  inspection,   that   the   symbols     p,     1;,     è' ,     occur  in     R     [5864],  by 

means  of  the  quantity  w  only  [58676]  ;  hence  it  is  plain,  from  [5867c'],  that  we  may 
[5867i]     consider   jR  as  a  function  of    p,  «,  <3';  and     R     as  a  similar  function  of    p+5p,     v-^5v, 

È'^àè',  as  in  [5866].  If  we  develop  5,  according  to  the  powers  and  products  of  5p, 
r5867A;]    ^v ,    5â',    by  formulas  [610 — 612],  and  retain  only  the  first  power  of  these  quantities,  which 

are  of  the  order     m',     we  shall  have, 

/dRX     ^     ,    fdR\     ,     ,    fdR\     ^^, 

Substituting   in    this,  the   expressions  of    à?,     àv,     àè'     [5867line  1,  5867^,  A],   we  get 
[5868]. 

*  (3172)     The  function  ^    [5360],  is  equivalent  to    R,    in  the  formulas  [5790,  5791], 

[5869a]    where  the  fixed  plane  is  supposed  to  be  the  primitive  orbit  of  m  [5775'  line  2].     Therefore 

we   must   substitute     R     [5868],  for     R,     in   the    values    of    dp,     dq      [5790,5791], 


VII.Api,..,S3.]  INVESTIGATION  OF  dp,  dg,  kc.  733 

expressions, 

Connecting   these   equations  with   those   in   [5786—5789,5794],  we    shall 
have,  by  taking  the  differential   of  the   terms   of  the  development    of    R 
the  corresponding  terms  of  each  of  the  elements  of  the  motion  of  m.     This       ' 
facilitates  very  much  the   computation  of  these  different  terms.     We   shall 
put, 

R  =  m'.k.coiJi'n't  —  int  +  i'e  —  û — o-u o-v 2o-"d")  [5^,72] 

for  one  of  the  terms  of  the  development   of    R.     Then,  the  corresponding 
terms   of   the   semi-major    axis     a  ;     of  the  mean  motion    fndt  ;     of  the 
epoch     £,•     of  the  excentricity     e;     of  the  longitude   of  the  perihelion     ^;     [5872'] 
and  of  the  quantities   p,  q;  will  be  represented  by  the  following  expressions, 
respectively  ;* 


observing,  that  the  partial  differentials  of  [5868],  relative  to     p,     q,     give  the  express 
[58696— c/],  by  using  [5869]; 


ions 


dR\  .  fdR\ 

—  ^=_sm.v.^— J-,  [5869ij 

—\  =  -   tan     J-       (~\ L      f'^\ 


Now  we  have, 


,      sin.^y    2.sin.^^-y         ^    ]_Cos.y  p 

COS.J7         2.sin.iv.cosi7  ~       sin.7      ~   sin.y       [^^52].  [5869e] 

Substituting  this  in  [5S69f/J,  and  then  using  the  resulting  value  for     (-—V     in     [57911 

we  get  [5871].     In  like  manner,  the  substitution  of  [5869&],  for     ( — \     in  [5790], gives 
[5870]. 

*  (3173)      Substituting    the  expression       R     [5872],     in   the  first    member  of  the 
vor,.  Til.  184 


734  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

[5873]  5a  =        • —^r~.'k-cos.(i'n't—înt-\-i's'—i!—gzi—g'-m'—2g"ô'); 

i'n  —  m 

3m'  iii^ 

[5874]       6P  =  L  fndt  = r— ^  :—.nk.sm.{tn't—int-{-i's'—ù—gz:—g'u'—2g"ê')  ; 

*  ■'  {ill — mf 

[5875]      J,=_.^_^^.|(lVI=72).^'p^{'^)-2«.(f;)jsin(^«^^^^^^ 

Periodical  ^ 

inaquali- 

ties  in  the  .  - 

«''■nents.  m'.an.\/l—e^     ,      }?+ï-(l V/l— «^)s  /•/    -  •.!•/,•  '     '       O     '/d/\ 

,j.j,7^T       5e= .  ^-  V-J^ ^^  .cos(iV«-in!;+i's'— IS— ^ra— g-^'— 2g  â')  ; 

,  ,  ,      .  ,  -^  )  •  sin.(i'«V— i»i^+i'£'— is— g-w— g-V— 2^'M')  ; 

e.(^n  —  m)         \de  J 


[5876] 


m'.  an.  ;/l_e2       /<?fc 

[5877]       i5î3  =  — 


[5878]       ¥  =       ,7î^:(îv-i)  •  U)  •  -n.(.«'^-nU  +  ..-.-..«-^^-2.^  0,* 

[5679]      h  =  r>-     ^";'-"^--  .  ^^"+(z-+£-).sin.«è7l.cos.(zV^-m^+i'e'-ù-^--^V-2g"â')  ; 
'■         ■*  (i?j  —  in).\/\—t^.s\n.y 


following  integral,  we  get, 

[5869/1  fan  =  —-, r-v  •  m'k.cos.{i'7i't-int-Yi'i'—ù-g^—g'^'—2g"ê'). 

<-       J  '  "  (in  —  tn) 

Substituting  this  in  [5796<Z],  we  obtain  Sa  [5873].  The  same  value  of  R,  being 
used  in  ^  [5794],  gives  [5874].  In  like  manner,  from  5; ,  de,  Szs  [5796/— A],  we 
deduce  [5375,5876,5877]. 

*   (3174)     Taking  the  partial  diflerentials  of    R     [5872],  relative  to     |3,     6',    fndt, 
[.5878o]     u,     and  using  for  brevity,      T=  i'n't  —  iiit  +  i'e' — is  —  gu  —  g'-a' — 2g"ô';     we  get, 

[5878c]  —  =  m'.k.i.sm.T;  \-—\z=  m'.k.g.sm.T. 

Substituting  the  first  of  the  values  [58786],  in  [5870],  we  get,  by  integration,     p     or     (5p 
[5S78]  ;  and  by  using  the  remaining  three  equations,  we  obtain  from  [5371],  the  expression 
[5878(i]    of    Sq     [5879]  ;    observing  that  we  have,     /3  =  2.sin.^^y.     [5S52]. 


VII.  App.-^S.]      INVESTIGATION  OF     i.fndt,     ôs,     Sa,     Se,     (3«,   Sj,,     Sq. 


735 


These  results  are  conformable   to   those  in  chap,    viii,  of  the  second  book  ; 
but   these  new  expressions   have  the  great  advantage  of  including  all  the      '*' 
powers  of  the  excentricities  and  inclinations.* 


*  (3175)  We  may  show,  that  the  expressions  of  Sa,  S.fndt,  Se,  S^  [5873, 
5S74,5S76,  5S77],  are  simihir  to  those  in  [1197,  1286, 1294,  &c.],  in  the  following  manner. 
The  assumed  value  of  R  in  [II 95'],  is  R  =  m'.Jc.cos.^i'S,' — i^-\-A)  ;  so  that,  if  we  [5880a] 
substitute  the  mean  values  2,'  =  n't,  ^  ^  jit ,  and  A  =  i's' — is — g-a — g'vs' — 2g  è  , 
it  becomes,  by  using  T  [5S7Sa],  R  =  m'.k.cos.T,  as  in  [5872].  Substituting  these 
values  of  A,  T,  and  (j,  =  1  [5750],  in  [1197]  ;  prefixing  also  the  sign  S  before 
the  terms,  in  the  first  membcfs  of  these  equations,  to  conform  to  the  present  notation  ; 
we  get, 


[58806] 
[588Cc] 


,'1\  2m'.  in       ,  ^ 

■5 .  (  -     =  —  ^n — —  •  ^^-cos.T  ; 
ay  m  —  m 


3m'.  ùi^         ,    .    ^ 
S^  =  -  ahsm.T. 

{i7i  —  in)-' 


Now,  by  neglecting  the  square  and  liigher    powers  of    Sa,     we   have     S  .  1-)= ; 

substituting  this  in  the  first  of  the  equations  [5880t/],  and  then  multiplying  by  — a"^,  we 
get  Sa  [5873].  The  expression  of  S^  [5880f/],  is  the  same  as  that  in  [5874]. 
Again,  if  we  neglect  e",  as  in  [1283']  ,  we  may  change  the  factor  [/l—e^  into  I,  in 
[5876],  and  then  it  will  become, 


[5880d] 
[58S0e] 


.              m  .an     ^ 
Se  = .  A: 


.? 


cos.T, 


[5880/] 


as    in  [1286,1285].     In  like   manner,  if  we  change  the   factor      ^i_ea 
[5877],  and  multiply  the  expression  by     e,     we  get, 

m'.an        /^^A       .     ^ 

eSzs  =  —  -:— r-  •     "1-      •  sm.  1  ; 

m' — m      \de  J 


into     1, 


[5880g-] 


which  is  the  same  as  the  integral  of    edzt 


[1291]. 


[5880ft] 


The  expression  of  Si  [5875],  may  be  derived  from  that  in  [1345],  neglecting  terms 
of  the  order  e'.  For,  if  we  multiply  edzi  [1258],  by  — \e  ,  and  add  the  product 
to  [1345],  we  get,  by  reduction,  an  expression  of  ds — Jc^Ju,  which  is  equivalent  to 
that  in  [5775'],  using  the  value  of  r  [5769]  ;  and,  from  this  we  easily  obtain  [5875]. 
We  have  thought  it  unnecessary  to  go  through  the  details  of  this  calculation,  as  it  is  evident  rsssoil 
that  the  result  must  correspond  with  [5775'].  For  similar  reasons,  we  shall  omit  the 
reduction  of    Sp,     Sq  ,     [5878,5879],  to  the  forms  [1341,  Sic] 


736  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.  Cél. 

[5880'!  ^^  "^'^"^^  ^"*^^  ^^^  secular    variations  of  the  elements  of  the   orbit  of  m, 

by  reducing     R     to  its  non-periodical  part,  which  ive  shall  denote  by, 

I-  J  R  =    m' F ,  [.\'on-periodicalpartof    R\ 

[5881]     Then     àR     vanishes,*  as  well  as     da ,     and  we  shall  have, 

[5882]  ds     =-   'ÎLl^^i^.  (l.^r^Ti).  (f)  +  2«^(f  ).,«'.«  J.  ; 

[5883]  de=         ^'•^V^^.n./^.Q; 

[5884]  d.   =    -    —-- .  ^— j  ; 

Secular 
inequali- 

[5885]  dp   =    -   ^^^,  .    (^^  j  ; 

,  m'.andt       fdFX 


or. 


[5887]  ^/»    =  :;7f^  •«!"•>'  -(^7^;; 

We  may  here  observe,  that  we  have,  as  in  [5755], 


[5889] 


„ m'.(xx'-'ryjj'+zz') m' 

r-*  p 


r5882  1  *  (3l'^6)     Taking  for     R     its  non-periodical  part     m'F,     we   shall  have     dR  =  0 

[5812,  5821',  5831, &,c.].     Subtituting  this  in  [5786],  we  get  d'a=0    [5881'].     With  this 

[5S826]  value  of  dR,  and  f---\=m'.(-—\  [5881],  we  obtain, from  [5788],  the  expression 
of  de  [5883].  In  like  manner,  from  [5789],  we  get  [5884]  ;  from  [5787],  we  obtain 
[5882]  ;  from  [5790,5791],  we  deduce  [5885,5886]  respectively;  lastly,from  [5870,5871], 

[5882c]     ^çgggj  [-5887^5883-1^  respectively.     In  all   the   equations  [5882— 5888],  quantities  of  the 

order     m'-     are  neglected  ;  but  they  are  exact  in  terms  of  the  order     m',     for  all   powers 

[.5882(i]  °  •' 

and  products  of  the  excentricities  and  inclinations. 


VII.App.p]  SECULAR  INEQUALITIES.  737 

and  hy  neglecting  quantities  of  the  order     m'^     it  becomes,*  [5889] 

R=  —  m'  .^        ^'J '  —-;  [5890] 

Therefore,  the  non-periodical  terms  of    R     depend  on   the  non-periodical 

part  of ;     hence  we  have,t 

P 

F  =  non-periodical  part  of  —  =  non-periodical  part  of ;  [5890'] 

this  part  being  developed  in  a  series  of  cosines  of  angles,  increasing  in  proportion 

to   the  time     t;     and     F    is  the   same,  for  both    planets  f5756].     U  we      [5891] 

vary  in  F,  the  elements    e,  ^,  p,  q,  of  the  orbit  of  m,  and  substitute  for  ^e, 

Sw,     op,     oq,     their  values,  which  are  given  by  the  integrals  of  the  preceding 


*  (3177)     If  we  neglect  terms  of  the  order     m'^     in  [5S25]  we  get, 
m' x"  m'      dilx'  .  m' x'  ddx' 

because,  by  neglecting  quantities   of  the    order     m'^,     we    may  put     M  ^  I      [3709ol.     [589061 
In  like  manner,  we  have, 

m'y'  ,  ddy'  m' 2'  ddz' 

7^=~'"-l^'  ~^^~'^-li^-  t5890c] 

Multiplying  these  three  equations  by     x,     y,     z,     respectively,  and  taking  the   sum  of 
the  products,  we  get, 

"'■'•  (^  '^'+yy'+zz')  {xddx'+  yddy'+  zddz') 

~ ^"^ =  —  m  . -~ -^  .  [5890rf] 

Substituting  this  in  [58S9],  we  obtain  [5890]. 

t  (3178)     If  we   neglect  terms   of  the  order     m'^,    we  may  substitute  the  elliptical 
values  of    x,     y,     z,     i',     y',     z'     [950, 952, 953,  Sic],   in  the  terms   of   the    second     ^^^^^"^ 
member  of  [5890],  which  are  divided  by     d(^  ;     and  then  we  shall  see,  that   it  contains 
no  terms  of  the  proposed  order,  except  such  as   are   periodical.     For,  if    x'     contain  a     ^^^^^^^ 
non-periodical  term,  its  second  differential     ddx'     will    depend   on   the  differentials  of 
the   elements     «',     e',     &:c.,  which   are   of  the   order     R,     or     m     [5786,  &.c.]  ;    and,      '■^^'^^"^ 

VOL.  III.  185 


738 


APPENDIX,  BY  THE  AUTHOR; 


[Méc.  Cél 


[5892] 


[5894] 


differential  equations  [5883 — 5886],  we  shall  find,  that  <'jF  vanishes,*  and 
the  same  result  is  obtained  with  the  variations  of  the  elements  of  the  orbit 
of  m'.  This  is  demonstrated,  in  [3767],  supposing  the  terms  of  fourth  and 
higher  orders  of  the  excentricities  and  inclinations  to  be  neglected. 


We  have,  as  in  [5867  line  1,  5867/i], 

[5893]  i|3  =  —  q.ûn.y  ;  53'  = 

If  we  suppose,  that     (5[3     and     àè'     are  increased  by  the  quantities     fZ(3,    cW, 


P 

sin./ 


respectively,  we  shall  have,t 


[5891d] 


[5891f] 


[5891/1 


[5892a] 
[58924] 

[5892e] 

[5892(i] 
[5893a] 


when  ddx'  is  multiplied  by  m'x,  as  in  [5890],  it  becomes  of  the  same  order  as  the 
neglected  terms  [5889'].  It  is  unnecessary  to  notice  the  periodica!  terms  of  ddx', 
because  they  produce  no  non-periodical  terms  of  the  first  order  in  m'.  xddv'  ;  therefore, 
tliis  term  may  be  neglected;  and,  for  similar  reasons,  we  may  reject  m'.yddtj',     m.zddz'. 

■m 
Hence    we    have,    by    noticing  only   the    non-periodical    terms,      R  =  — —      [5890]. 


Substituting  this   in    [5881],  and   dividing  by    m',    we  get     F^ ,     as  in    [5890']. 

Finally,  as  the  value  of  p  [5756]  is  symmetrical,  in  the  co-ordinates  of  the  two  planets 
X,  y,  z,  x,  y',  z',  respectively  ;  it  is  plain,  that  the  non-periodical  part  of  R, 
or     F,     must  be  the  same  for  both  planets,  as  in  [5891]. 

*  (.3179)  If  we  vary  in  F,  the  elements  e,  ra,  ;?,  q,  of  the  orbit  of  m,  we  shall 
get,  in  like  manner  as  in  [5795a — 6,5795],  by  noticing  only  the  secular  variations  of 
these  elements  ; 


àF-- 


m-^'- 


! 


V..;-S  +  U>+(ï)-M 


The  integrals  of  the  values  of  de,  rfra,  dp,  dq  [.5883,  5884,  5885,  5886],  are 
found,  by  changing,  in  these  functions,  dt  into  t,  neglecting  terms  of  the  order  m'^; 
by  this  means,  we  get  (5e,  53i,  r5p,  &q,  respectively.  Substituting  these  values  of 
èe,  <5ra,  in  [5892a],  we  find,  that  the  terms  depending  on  these  quantities  mutually 
destroy  each  other.  In  like  manner,  the  terms  which  depend  on  'îp,  (5y,  mutually 
destroy  each  other  in  [5892n]  ;  therefore,  the  whole  of  the  second  member  of  [5892ff] 
vanishes,  and  we  have,  as  in  [5892],  i5F  =  0.  In  a  similar  manner,  we  find,  that  HF 
vanishes,  by  the  substitution  of  the  variations  of  the  elements  e',  ts' ,  p' ,  q' ,  oftiie  planet  m'. 

t  (.3180)     Taking  the   differentials  of  [589.3],  and  writing,  as  in    [5894],     dfi,     dû', 
for     d.à^,     d.S6',     we  get, 


VII.App.§3.]  SECULAR  INEQUALITIES.  739 

rf/3  =  —  dq.sin.r  ;  dt)'  =  —  -^.  [5894'] 

^  sin. 7 


Substituting  the  values  of     dp ,     dq  ,     we  shall  get. 


* 


d^    =    _    '"'■""^       ('l^  .  [5895] 


/l_ea.sin.y      (  \  ^^  /  \d^J   ) 


We  have,t 


dfi  =  —  âq.s\n.j—qdr.  COS.  7  ;  (W  =  —  ^  ,  ^-^^  _  [58936] 

sin.y         sin.a> 

Now,    y  [5849]  is  of  the  same  order  as  the  greatest  latitude  of  the  planet  m',  above  the 

orbit  of  m  ;  and  this  varies,  in  consequence  of  the  perturbations  of  tlie  latitude,  by  quantities 

of  the  order  m.     Moreover,     p,     q     [5863],  are   of  the  same  order  as     s,     which  is  of  ■' 

the  order    m  [5858]  ;  therefore,  pt/y,    qdy,    are  of  the  second  order  in  m,    m',  and  may 

be  neglected;  hence  the  formulas  [58936],  become  as  in  [5894']. 

*  (3181)     Substituting     dp     [5887],  in  the  expression  of    d&'     [5894'],    we    get 
[5895];     moreover,  the  differential  of    |3  =  1 — cos.y     [5852],    gives     f/p  =  f/y. sin.y.     ^  ^ 

Now,  it  is  evident,  that  we  may  put  this  value  of     </(3     equal  to  that  in  [5894']  ;  because 
p    would  be  constant,    if  it  were  not   for  the  mutual   action  of  the  planets  ;  so  that  the     ^58955] 
whole  of  this  variation  of    (3,     arises  from  that  of    5^  ;     hence  we  get, 

—  rfj.sin.y  =  f7y  .sin.  7;     consequently,     dy  ^^ — dq.  [5895c] 

Substituting  the  value  of    dq     [5888],  we  get  [5896]. 

t  (3182)     If  we  put    g"'^g",     è  =  è',     in  the  term  of    R     [958],  it  becomes  of 
the  same  form  as  in  [5872].     Making  these  substitutions  in  [959],  we  get, 


0  =  i'—i—g  —  g'—2g"  ; 


L5897a] 


which  must  be  satisfied  for  all  the  terms  of  R  [5872].  Now,  F  [5881]  comprises 
the  non-periodical  terms  of  R,  or  those  wliich  do  not  contain  i'n't — hit  [5872]  ; 
and,  as  n,  n'  are  incommensurable  [1197'],  we  must  necessarily  have,  in  this  case, 
i'=0,     1=0.     Substituting  these  values  of    i',     i,     in  [5897a],  we  get, 

0  =  5-  +  5-'  +  2  g",      as  in  [5899]  ;  [5897c] 

and  the  value  of    R     [5872]  becomes, 


740  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.CéJ. 

/dF\  /dF\        /dF\ 

because,  if     F    be  developed  in  cosines  of  the  form, 

[5898]  F=^  H.COS.  (g^  +^V  +  2g"ô')  ; 

the  sum     g-'rg'-\-2g"     of  the   coefficients  of  the  angles     ro,     ra',     ê',     must 
[5899]      be    equal  to  nothing,  to  render  this    term    independent  of   the    arbitrary 
origin  of  those  angles  [5897c].     Therefore,  we  have,* 

m'.amit         (^       ^.      /iIF\    ,     /dF\   } 
Hence   we  obtain,  by  means  of  the  preceding  expressions  of    de,      de',-f 


[5897c']  R^m'.Ic.cos.(-gu-g'^'-2g"ê')  =  m'.Jc.cos.(gz^+g'^'+2g"6'). 

Hence  we  get,  by  means  of  [5890'], 

[5897c;]  F=l'.cos.(gvi-]-g'T^'+'2g"è'),     as  in  [5898]  ; 

H   being  used  for    k.      The   partial  differentials  of    F,     relative  to     w,     to',     ê'     give, 
[5897e]    by  putting,  for  abridgement,     w  =^  gTs-{-g'-m'+2g"é', 


/(IF 
[5897/]  (^ 


'%)  =  -gk.sin.^v  ;         (^i)  =  -^-'^'-sin.w  ;  (^,)  =  -  2g"k.sm.w  ; 


h 


lence. 


[5897g]  0+Q+(^)  =  -^•(â-+.-'+2g")-sin.w  =  0       [5897c]. 

This  last  expression  is  equivalent  to  that  in  [5897]. 
[5900a]        *  (3183)     Substituting  the  value  of    {j~\     [5897],  in  [5896],  we  get  [5900]. 

f5901a]  t  (3184)  The  expression  of  dy  [5900]  depends  upon  the  disturbing  force  of  m' ; 
and,  if  we  call  this  part  dy^,  and  put  the  other  part,  depending  upon  the  disturbing 
force  of    m    upon  ?n',     equal  to     dy^,     we  shall  have  the  whole  value     dy=dy^-\-dy^. 

"■  Substituting     f/y,     for     dy,     in  [5900],  also     1 — |3  =  cos.y     [5852],  then  multiplying 

[5901c]  by  ^-^,  weget  [5901e].  Multiplying  [5883]  by  j-î-,  we  obtain  [5901/];  adding 
this  to  [5901c],  we  get  the  first  of  the  formulas  [5901^]  ;  and,  by  substituting  the  value  of 


-^  )  = ^ ,     which  is  easily  deduced  from  [5883],  by  changing  reciprocally 

\da'J        m.a'n'dt.\/[\ — t'-) 

[5901c']    ,^i,e  elements  of  m  into  those  of  m',  which  does  not  change     jP     [5891],  we  get  the  last 


VII.App.s^3.]  SECULAR  INEQUALITIES.  741 


f/y.sin.y  eile  e'dc'  m.a'n'.ede 


cos.y  1  —  e-         1  —  e'^  m  .an.\/l  —  e^.^/l— e'a.cos.  y 

m',  an. e' de' 
m.a'n'.\/\—e'i  •  \/\—e"^.cos.y 

Multiplying  this  equation  by     — 2.^i— e^ .  ^/i— e'^.cos-r  ,     and  taking  its 
integral,  we  get,* 

m.\/a  g,        m'.\/a' 


[5901] 


2.1/1— e2.v/Ti:?2.cos.7  =  constant ~  •i\—e^) -^^- .  (\—e'^).  [5902] 

m  y  a'     -  '        m-v/rt      ^ 


expression  in  [590 1»-].     The   similar  formula,  corresponding  to  the  action  of  ?«  on    m',    is 
found,  by  changing  the  elements  of  711  into  those  of  m',  and  the  contrary  ;   by  this  means,     [sooirf] 
we  get  [5901A].    Adding  together  the  expressions  [590l5-,/i], and  substituting  dy  [.5901e], 
we  get  [590 J]  ; 

dy^.s\n.y  m'.andt      C  /dF 


COS.7  \/\- 


(.2 


\C!l\+JL_,(^].  [5901e 


ede  m'.andt 


1— e^  V/î=^2    *  ^  V^J  I  ' 


[5901/-] 


dy^.sin.y  ede  m'.andt         1        /'^^X  in',  an. c' de' 


COS.7  1 — f^  \/l— e2     COS.7     \dc/y  OT.a'n'.y/i_e2.y/l_e's.cos.7  ' 

rfy,.  sin.^    ,     c'f/e'  m.a'n'.ede 

-^ +  1 72    = ; , ,^= .  [590U] 

cos.y  1 — €■'  m.an.\/l—e^.yi—e'^.cos.y 

*  (3185)       Multiplying  the   equation    [5901]    by     — S./HT^.^/JZITa.  cos.-/,     we 
obtain, 

^  ^  '  v/(l-e2)  \/(l-e'2) 

[£9C2o] 
m.a  n     ^    ,      ,    m .  an  ,  ■" 

= .  2ede  -{ r,  .2eWe'. 

m  .an  7n.a  a 

The  integral  of  the  first  member  of  this  equation,  is  the  same  as  that  in   [5902].     In  the 

second  member,  we  must  substitute     an  =  «"*,     an'  =  «'-=     [5778a],  and  it  becomes,       t^'^^^^l 

m.y/a      ^    ,      ,    m'.\/a'     ^  ,  .  , 
,  ,  ,  •  Série  -\ —  .  2e'Je'  ;  rwnQrl 

which,  by  integration,  gives  the  second  member  of  [5902].     Finally,  we  may  observe, 

that,    in   all  the  differential    equations   [5882—5902],  we  have  neglected  terms  of  the     ^^^^^^^ 

second  order  in  7n,  m'. 

VOL.  III.  186 


742 


APPENDIX,  BY  THE  AUTHOR; 


[Méc.  Ctl. 


If  we  put,  for  brevity, 


[5903] 

[5904] 
[5904'] 

[5905] 
[5905'] 
[5906] 
[5907] 


v/«-(i-e-)  =/; 


^„'.(l_e'2)  =/'; 


we  shall  have,* 


f3  = 


[,nf+m'fY-c^ 
2mm'.ff' 


â  being  an  arbitrary  constant  quantity,  independent  of  the  elements. 

The  preceding  value  of  d^  [5895],  expresses  the  motion  of  the 
intersection  of  the  two  orbits,  produced  by  the  action  of  /w',  and  referred  to 
the  orbit  ot  m'  [5862^].  We  shall  suppose  an  intermediate  plane,  between 
these  two  orbits,  and  passing  through  their  mutual  intersection  ;  and  shall  put 
9  for  the  inclination  of  the  orbit  of  m  to  this  plane.  To  obtain  the  differential 
motion  of  the  node  of  the  orbit  of  m,   upon  this  plane,  arising  from  the  action 

of  m'    upon  m,  we   must  multiply  the  preceding  value  of     de'    byf     "-^^  . 


[5904o] 


[59046] 


[5904c] 


[5907o] 


[59076] 


*   (3186)     From  [5903],  we  obtain, 

i/l_e2  =  ^^;  wlZTTa  =  4-    ;       also     COS.y:=l— p      [5852]. 


Substituting  these  in  [5902],  we  get, 


■P 


n'.f 


2.(1— p).-—=^  ==  constant-  -    ,  —         , 

\/ aa'  m.\/aa        m.y  aa! 

multiplying  tliis  by     ?«?«'.  \/^,     and  putting, 

Hm'.\/;i^'X constant  =  c^     we  get,     2.(1 — ^).mm'ff=^  c^ — m-.f^ — m"^.f^  ; 

whence  we  easily  deduce     p     [5904]. 

t   (3187)     In  the  annexed  figure,     NM,     NM,     represent   the  orbits  of  the  planets 
m,    m',    respectively ,     supposing  ^' 

them  to  be  viewed  from  the  sun, 
and  referred  to  the  concave 
surface  of  the  starry  heavens  ; 
NDM"  is  the  intermediate  plane, 
or  orbit  ;  and  N  the  common 
intersection,  or  node,  at  the  ^-. 
commencement    of  the   time     dt. 


Orlrii  cj"  TTt 


VII.App.'§.3.] 


SECULAR  INEQUALITIES. 


743 


Putting  this  motion  equal  to     dt\     we  shall  have, 

m'.(]t       sin.  y      /f/jP' 
dé  =  — 


[5807'] 

[5908] 
f         sin. (J)      \dp . 

If  we  put     ?'     for  the  inclination  of  the  orbit  of  m,  upon  the  same  plane,      [^'-^0^] 
we  shall  have     ç+çj'  =  7  ;     and,  [5909] 


Then  we  shall  have,  as  in  [5905',  5909], 

the  angle  MNM"=  9  ;     the  angle  MNM"  =  <p'  ;     the  angle  MNM  =  ?+?)'=  y  ; 
the  arc  ND  =  rfé  ;     the  arc  NE=  cW      [5907',  5905]. 

We  shall  now  suppose,  that  the  action  of  the  body  m'  upon  in,  changes  the  orbit  of  m, 
from  MN  to  the  infinitely  near  orbit  MDE,  in  the  time  iJt  ;  by  this  means,  the 
node  JV  moves  through  the  space  ]VE=cU'  [5905,  5862,c,d].  upon  the  orbit  of  m  ; 
or,  through  the  space  ND=  dé,  upon  the  intermediate  orbit.  Then,  in  the  infinitely 
small  triangle     NDE,     we  have, 

sineNDE  :  smeNED  ::  NE:  ND  ; 

and,  if  we  neglect  infinitely  small  quantities,  we  have, 

angle  ND  E  =  ip  ;         angle  iV£D  =  180"— 7  ; 
hence  we  have,  in  symbols, 


sin. 9  :  sin. 7  :  :  de'  :  de  ;    consequently,  di)  =  Jd' 

Substituting  in  this,  the  value  of    dé'     [5895],  we  get, 

m'.andt    Biit.y   /dF\ 
^1^^'  sin.((>'\ 


sm.y 
sin.(p 


[5907]. 


d^J  ' 


and,  since     an  =  o~'     [5902&],  we  have, 

an  1 


\/l— e 


^a:^)  =  7   ^^««^]  ■' 


hence  the  preceding  expression  of  de  becomes  as  in  [5908].  In  like  manner  we 
obtain  the  value  of  d'ô  [5910],  which  represents  the  motion  of  the  node  of  the  planet  m' 
by  the  action  of  m;  and,  we  can  easily  deduce  this  value  of  d'é  [5910],  from  that  of  dé 
[5908],  by  clianging  reciprocally  the  elements  and  mass  of  m  into  those  of  ?«';  by  which 
means,  /  changes  into  /',  in  [5903]  ;  and  dé  [5908],  changes  into  d'ô  [5910]; 
F  remaining  unaltered  [5891]. 


[5907c] 
[5907rf] 


[5907e] 


[5907/-] 


[5907/'] 


[5907/"] 


[5907^:] 


[5907A] 


[5907t] 


744  APPENDIX,  BY  THE  AUTHOR;  [Mée.  Cél. 


m 


„                ....lit     sin.  y       fJFx 
[5910]  d'&  = — ■  .  -. ;■  .      —  )    ; 

[5911]  (He  being  the  motion  of  the  orbit  of  m',  upon  this  plane,  produced,  bj  the 
[5912]      action  of  m  upon    ;/*'.      The   motions   de  and  d'è    will  be    equal,   and   the 

intersection  of  the  two  orbits  will  remain  iqyon  the  plane  we  have  just 
[5912']     considered,  if  it  divides  the  angle  of  the  mutual  inclination  of  the  orbits   j,    so 

that  loe  may  have,* 

[5913]  mf.  sin.?  =  Hiy.  sin.9'. 

This  result  is  the  same  as  is  found  in  [1164]  ;  ivhere  ive  see,  that  the  plane 
[5913']  .        .  ,  .  L  J  '  r 

m  question,  is  that  of  the  maximum  of  areas  ;  and,  that  we  have, 

[5914]  c  =  mf.  cos. ?+my.  cos.ip'- 

This    equation   [5914],   being  combined  with   [5913],   gives   the  integral 
corresponding  to  [5904]  ;  namely, f 


[5915]  P  =  ■ 


2mm'.//' 


*  (3188)     Putting  the  two  expressions  [5908,  5910]  equal  to  each  other,  and  dividing 

,       ,  ,  ,    .        /'dF\  m'  m  ,  •  ,    •         -, 

r59]2al     bv  the  common  factor     — dt.sm.yA- —   ,     we  get,     - — : —  =  — — -, —  ;     which  is  easily 
i-  J       ■  \dp  /  /■  sin.<P         / .  sin. 9  •' 

reduced  to  the  form  [591.3].     This  equation,  by  the  substitution  of  the  values  of    /,    /' 

[5903],  becomes  as  in  [1 164  line  1],  corresponding  to  the  equation  of  the  maximum  of  the 

areas  ;  and,  by  a  similar  reduction,  we  may  prove  the  identity  of  the  expressions  of    c    in 

[1165,5914]. 


[59126] 


t   (31S9)     The   equation  [5913]  may  be  put  under  the  form, 

[5915a]  0=  — '«/sin.çj+m/'.sin.©'. 

Adding  the  square  of  this  equation  to  the  square  of    c     [5914],  we  get  successively,  by 
using     y,     p     [5909',  5852]  ; 

[59156]     c^  =  »î^-./^-(cos.^ip-f-sin.^^))+2mm'.//''.(cos.9'.cos.ç3-sin.ç)'.sin.ç))-|-;«'^./'2.(cos.V+sin.V) 
[5915c]        =m^P+2mm'.ff.cos.{<p'+<p)+nr-.f'^^7n^P-^2mm'.ff.oos.v+m'^.f^ 
[5915rf]         =  m\f^+2mm'.ff.  (  I_^)+m'2./2  =  [,nf-^>n'.fy-2mm'.ff'.  (3. 

From  this  last  expression,  we  easily  deduce  the  value  of    |3    [5915];    and,  by  an  inverse 
■^^^'^'^     operation,  we  might  deduce  [.5914]  from  [5904,  5913]. 


VlI.App.^S.]  SECULAR  INEQUALITIES.  745 

These  two  equations,  give  also  the  following  expressions  ;* 


[5916] 


m'f'-s'm.y                                    .       ,        mf.sm.y 
Sin.?  =  — ;  sin.?  = ; 

c  c 

COS.Ç3  =  ^-—- ^   ;  C0S.9  = ,r~ri^: '  [5917] 

2m/. c  2mJ  .c  >•        J 

We  shall  denote  by   -a^    and  «/,   the  perihelion  distances  of  m   and  m',  from      ^59191 

the  line  of  mutual  intersection  of  the   orbits.     Then   we  shall  obtain     d^^ , 

by  subtracting  from   the  differential     d:^,     the   motion  of  that  intersection 

dt\    referred  to  the  orbit  of  m  ;t  and,  it  is  evident,  that,  for  this  purpose,  it  ^ 


sin  © 
*  (3190)     From  [5913]  we  get     mf=nif'.—-^    ;     substituting  this  in    [5914],  we     [5916(1] 

obtain  successively,  by  using     y     [5909']  ; 

m'f    ,             ....                ,,        m'f     ■     ,    <    i\       ™y    ■ 
c  =  - —  .   cos.o.sin.ffl  +sin.a).cos.ç)  ?  ^= .sm.((D+<p  )=-. —  .sin.y.  [591651 

sin.ip    '  ^         ^    '  ^'         sin. If  \-    ^  ^  /        sjD^ç,  1.  J 

From  iliis  last  value  of    c,    we  easily  obtain     sin.çj  [5916].     Substituting  this  expression 
of     sin.?     in  [5913],  and  dividing  by     m'f,     we  get     sin. 9'    [5916].     Again,  we  have, 

c— m/.cos.ip=:w7'.cos.9'     [5914]   ;  '  [5916c] 

adding  the  square  of  this  to  the  square  of  [5913],  and  reducing,  we  obtain, 

c2_2TO/c.cos.(p+my2=:OT'y2  ;  [5916d] 

whence  we  easily  deduce  the  value  of    cos.»?     [5917]  ;     substituting  this  in  [5914],  we 
get     cos.(p'     [5917].     Losing  the  value  of    sin.ip     [5916],  we  get,  from  [5908]. 

''--Jf'-Q      t^^'^J'  [5«16e] 

and,  by  substituting  the  value  of    c     [5915<^],  we  get  the  second  form  of    dé     [5918]. 

f   (3191)     Drawing     DF    perpendicular  to     NM,     in  fig.  80,  page  742,  we  have, 

JVF  =  ND.cos.FND  =  dê.cos.ç     [5907c,  (Z]   ;  [5921a] 

and,  if  we  substitute  the  first  value  of    do     [5918],  and  that  of    cos.tp     [5917],  we  get, 

VOL.  III.  187 


746  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

is  only  necessary  lo  multiply  it  by     cos.;?  ;     now,  we  have, 

(m/+m'/'— m'/'.p)      ,       /dF\ 

[5921]  dé.cos.ç=: —  ^  •'^   ''        -^-'.dtJ-j-y 

therefore,  we  shall  have,* 
[5922]  ed^^  =  —  m .  andt.\/[—e^.  (-77)  +  -^^ — "^-yp — - — -  ^  -  edt  .  i  —  j  ; 

[5923]  ede   =         m'.  andt.\/Y^^.  (~\  . 


[59216]  d^  . COS.,  =  -  ~^t-X__£_i.  J, .  (^_  ^  . 

Substituting  c^  [5915rf],  and  dividing  the  numerator  and  denominator  by  2mf,  we 
[5921c]     get  [5921].       Subtracting  this  quantity  from  the  whole  motion  of  the  perihelion  of  the 

planet  m;  namely,     d-a,     we    get     dw^     [.5921e]  ;    which  represents  the  increment    of 

the  distance  of  the  perigee  of  the  planet  m  from  the  moveable  node.  In  the  same 
[5921(/]     manner,  we  get     c/ar/  [5921/]  ;     or,  it  may  be  more  easily  derived  from   c?w,  [5921e], 

by  interchanging  the  elements  of  m,  m',  in  the  usual  manner  ; 

[5921e]  d.,  =  d.  +  ^:^J^-^^^ .  ,,  .  Q   ; 

[5.31/]  .«-..'+i^^^^i'^=^)../..Q. 

*  (3192)  Multiplying  the  expression  of  d^^  [592 le],  by  e,  and  substituting 
da,  [5884],  we  get  [5922].  In  like  manner,  multiplying  the  expression  of  d.-us' 
[5921/],  by     £■',     and  substituting, 

m.a'n'dt.wT^3       /dF\ 
[5922a]  rf«  = -, .  [—j  ; 

which  is  deduced  from  [5884],  by  changing  reciprocally,  the  elements  of  m  into  those 
of  m' ;  we  get  [5924].  Now,  we  may  suppose,  as  in  [592G],  that  w,  ra/,  take  the 
places  of    -ra,     w',     respectively,  in  the  function     jF  ;     and  then  we  shall  have, 

^  '  \d-aj  \d-^J       \dTsJ  yd'^J  \d-a,J       xdis'J 

If  we  neglect  quantities  of  the  order     m  ,     we  shall  get  from  [592 If,/], 


VII.App.§3.]                            SECULAR  INEQUALITIES.  747 

In  like  manner,  we  have, 

«*;  =  -  „,.«V*VI=7»-  ('^)  +  ("■/+'"/-'"/•  W  .  ,d,  .  C;^)  ;        !=»«, 

e'de'    =         m.a'n'diyT—r-.  f^^j  .  [5925] 

F  is  a  function  of     a,     a',     e,     e',     ra,     w',   and   f3.     If  we  eliminate     (3      [5926] 
from  the  second  members  of  these  equations,  by  means  of  its  value, 

^_(^^f^)J-C^        [5915],  [5927] 

2mm  .Jj 

we  shall  obtain  four  differential  equations  between  the  four  variable  quantities 
e,     e',     ^^,     3'.     We  may  give  them  a  still  more  simple  form,*  by  putting, 

h  =  e.sin.:^^  ;  I  =  e.cos.^^  ;  [5928] 

h'  =  e'.  sin.^/;  /'  =  e'.  cos.w'.  [5929] 

This    renders    them  linear,    when    we   neglect  the  higher   powers  of    the 
excentricities,  and    facilitates    the    farther    integrations,  by  approximation,     [5929'] 
to  any  powers  of  the   excentricities. f     Thus    we  shall    have    the    position 

so  that  by  rejecting  quantities  of  the  order     m  ,     we  shall  have, 

Substituting  the  first  of  these  expressions  in  [5883],  and  multiplying  by     e ,    we  get  [5923] , 
in  which  terms  of  the  order     m^     are  neglected.     The  second  of  the  expressions  [5922rf], 
being  substituted  in  the  value  of    de',     deduced  from     de      [5883],  by  interchanging  the      '■        "^ 
elements  of    m,     m',     gives  [5925]. 

*  (3193)     We  have  already  seen  the  effect  of  similar  substitutions,  in  simplifying  such 
results,  in  [1022,  1046,  10S9,  &c].  "•' 

t  (3194)     After   we    have    obtained    the    values    of    h,     h',     I,     /',     by    methods 
analogous  to  those  in  [1097,  &c.],     we  may  determine  e,  e',  w,    ,w/,  from  [5928,5929].     [5929a] 
Then     a,     a',     being  constant  [5881'],   we  shall  have    /,    /',     from   [5903].      The 
constant    quantity     c^     is     known,   from   the  values     of     f,    f,     /3,     at    the    epoch     [5929i] 
when     ^  =  0,     by  means  of  [59I5(/]  ;  and  at  any  other  time     t,     the  value  of    /3     will 
be  known,  by  substituting  the  corresponding  values  of    f,    f ,     in  [5927],  then  from     (3,     [5929c] 


748  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

of  the  orbits,  relatively  to  the  variable  position  of  the  line  of  their 
[5930]  mutual  intersection.  We  shall  then  have  the  inclinations  of  their  orbits 
to  each  other,  by  means  of  the  preceding  value  of  [3  ;  and  we  may 
thence  obtain  their  inclinations  upon  the  plane  of  the  maximum  of  the 
areas,  by  means  of  the  preceding  values  of  f  and  o'.  Lastly,  we  shall 
have  the  motion  of  the  intersection  of  the  two  orbits,  upon  this  maximum 
plane,  by  integrating  the  preceding  expression  of  de  [5908].  This 
seems  to  he  the  most  general  and  simple  solution  of  the  problem  of  the 
secular  variations  of  the  planetary  orbits. 


[5931] 


[5931'] 


We  shall  now  resume  the  equation  [5915^], 

[5932]  c^-   (mf-^mfy  —  2mm'.ff'.^. 

If  we  neglect  quantities  of   the    fourth   power  of  the    excentricities    and 
[5932']      .  .  .        .,,      .        „ 

inclinations,  it  will  give,* 

/      /-      '2,1        2^771'.  y/^  (3 


[5933]  constant  =  m.\/a .  e'+  m'.  \/«'.  e'^  + 


ffl.v/«+  m'.  \/a' 


[5929d] 


we  obtain  y  [5852].  With  these  values  of  m,  m,  c,  f,  f,  7,  we  deduce 
cp ,  (p',  from  [59 16 or  59 1 7],  and  de  from  [5918],  whose  integral  gives  è.  Thus  we 
shall  obtain  all  the  elements,  in  the  same  manner  as  in  [5930,5931]. 


*  (3195)     The  quantity     |3     is  of  the  second  order  in     y     [5852],  and  by  neglecting 
terms  of  the  fourth  order,  we  may  put, 

[5933a]  _  2mm:.  ff.  (3  =  —  2mm'.  ^^.  (3     [5903]  ; 

also, 

[5933a']  ff  =  vA7.  v/r=ra.v/i^=?â  =  /^'.  (1  —  1  e^—  | e'2) . 

Hence  the  expression  [5932],  becomes,  without  reduction, 

[59336]     c^=  m'.a.  {\  —  c~)-\-2mm'.\/^.{\^ie^—^e'^)-{-m"^.  a'.(l  — e'^)  _  2mm'. /^.  |3. 

Then,  by  transposition,  we  get  [5933c],  and  its  second  member  is  easily  reduced   to  the 
form  [5933rf]  ; 

[5933c]     — c^+TO^.  r(+m'2.a'+2»im'.  /^=  m^.  o.e^+mm',  v/W.  {e^+e'^)-{-m'^.  a'.  €'^+2mm'.^^'.  (3 
[5933i]  "  ={m.\/â-\-m'.\/a').{m.\/â.t~+m'.\/â'.e'^)-\-2mm'.\/'^:^. 

If  we  divide  this  by     m.^â-j-  »i'-  \/a' ,     we  shall  find,  that  the  first  member  is  a  constant 
quantity,  and  the  second  member  becomes  as  in  [5933]. 


VII.App.§4.]        EFFECT  OF  THE  OBLATEINESS  OF  THE  EARTH.  749 


D~ 

(ap— la?).  — .(f.3_^-)     .  [Terra  of  ii] 


[5034] 


[5935] 


and  bj  what  has  been  said  in  [5786,5842, 5881',  &c.],  a  and  a',  are 
constant,  noticing  the  square  of  the  disturbing  force  ;  therefore,  we  shall 
have,* 

0  :=  7n.\/a  .  e  e  +  m  .Wa'.  eoe  -j -^ Li-  . 

my  a  +  m'.  \/a' 

This  equation  is  of  the  same  form  as  that  which  is  found  in  [3964],  noticing 
the  terms  dependmg  upon   the   great    inequalities  of  Jupiter  and    Saturn. 
Hence  it  appears,  that  the  invariable  plane,  determined  in  [1 162',&c.,5913],      [5936] 
remains  invariable,  even  when  we  notice  some  terms  of  the  order  of  the 
square  of  the  disturbing  force  [.5935c]. 

4.  We  may,  by  means  of  the  differential  expressions  of  the  elements, 
determine,  in  a  very  simple  manner,  the  influence  of  the  figure  of  the 
earth  upon  the  moon's  motion.  We  have  seen,  in  [5340,5438],  that  this 
action  produces  in     R,     the  following  term  ; 


[5987] 


ap  is  the  oblateness  of  (he  earth  [5333];  a.:^  is  the  ratio  of  the  centrifugul  force     [5938] 
to  gravity,  at  the  equator  [5333']  ;     D    is  the  mean  radius  of  the  terrestrial 
spheroid  [5334]  ;  and    (^    the  sine  of  the  moon^s  declination  [5334']  ;  which      [^''39] 
is  represented  as  in  [5344],  by, 

i^  =  v/l — s-.sin.x.siuj/tj+s.cos.x  ;  [5940] 

or,  more  accurately,  as  in  [5344e], 

sin.X.sin./î)-j-s.cos.X 

(^  =  -=:z ;  [5941] 

yl-\-ss 

fv    being  the  true  longitude  of  the  moon,  counted  from  the  vernal  equinox 
[5345];     >•    the  obliquity  of  the  ecliptic  [5S^:\]  ;    and    s    the  tangent  of  the      '•^^^^^ 
moon' s  latitude  [4759  "]. 


*   (3196)     We  have     2|3  =  4.sin.^4-/    [5852],  and,  if  we  neglect  terms  of  the  order 
y^,     we  get     2(3  =  y^.     Substituting  this  in  [5933]  ;  taking  its  variation,  dividing  by    2,     [5^35a] 
and  neglecting  terms  of  the  second  order  in     Se  ,     Se,     Sy  ,     v/e  obtain  [5935],  which  is     [59356] 
similar  to  that  in  [3964].     The  equation  [5935]  is  correct   in    some  of  the   terms   of  the 

VOL.  III.  188 


760  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.Cél. 

The  part  of  R,  depending  on  the  sun's  action,  is  of  the  form*  r^Q', 
neglecting  terms  depending  on  the  sun^s  parallax,  ivhich  are  very  small 
[5944c].     Then  we  shall  have,  very  nearly, 

[5944]     i2=rQ'+(ap-iap).  — .(sin.^x.sin.yi'+2s.sin.x.cos.x.sin./i'-|)     [5944e,&;c.]  ; 

which  gives, 

2r  .(  —  )=2a.(  —  )=4r^Q'-6.(a--ia;).— .(sJn^À.sinyi;-f2s.sinx.cosx.siii/r--i.}. 


[5945]      ^r.^-y  =  ^«.^-^  = 

We  shall  here  notice  only  the  inequalities  depending  on  the  angle  gv — fv  ; 
[5946]      g^  being  what  is  called  the  argument  of  latitude  ;    then  we  shall  have. 


[5935cl     order     mr'     [3964',  &.C.],  but  others  of  the  order     nî^,    m^.e^.Se,     Se^,     Sic,  are  neglected, 
as  in  [1 150',  5932',  59356,  &ic.]. 

*   (3197)     Substituting   the  values   of     u,     u,     [4776, 4777e]  in     (^     [47S0],  and 
developing  it  in  a  series  ascending  according  to  the  powers  of    r,     we  get, 


[5944o] 


1  m'      C  7"^  r^  ) 

Q  =  -  +  -  •     1  +  -4  .  -    +  i?  •  -3  +  &c.     ; 
r  r       (_  r  -  r  y 


[5944a']    ^^     S,  &1C.,  being  quantities  which  contain     v,     s,     v',     s'.     Substituting  this  in  [5438], 

we  get, 
[5944i]  R  =  --.)^l+A.-+B.~  +  Uc.^. 

The  first  term  of  this  expression  of  R  ,  produces  nothing,  in  its  partial  differentials, 
taken  relatively  to  the  elements  of  the  moon's  orbit  ;  we  may,  therefore,  neglect  it;  and 

[5944c]  ^jg^  |.j^g  terms  depending  on  r^,  r^,  &tc.,  on  account  of  their  smallness  [5943].  By 
this  means,  the  expression  of  R,  is  reduced  to  its  greatest  term,  depending  upon  r^, 
which  is  represented  by  r^Q'  in  [5943],  and  is  of  the  same  order  as  that  of  the 
disturbing  force  of  the  sun  upon   the  moon  ;      Q'     being  a  function  of    v,    s  ,     r',    v',    s' 

[5944d]  [5944a, a'].  Finally,  we  may  remark,  that  the  symbol  Q'  is  denoted  by  Q,  in  the 
original  work,  but  we  have  placed  an  accent  upon  it,  in  order  to  distinguish  it  from  the 
value  of     Q     [5944o].     Adding  this  chief  term  of    R     to  that  in   [5937],  we  get, 

[5944e]  R  =  r2Q'+  (ap— iaç)  .  —   .  (m.^— è)  • 

Substituting  the  value  of    (a     [5940],  and   neglecting     s^,  it  becomes  as  in  [5944].     Its 
[5944/]     partial  differential,  relative  to     r,     being  multiplied  by     2r,     and  then  substituting  [5774], 
gives  [5945]. 


VII.App.§4.]   EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH. 

very  nearly,     s  =  y.s'm.go     [481  8]  ;     7    being  the.  inclination  of  the  moon'' s 
orbit  to  the  ecliptic  [4813].     Thus,  we  shall  obtain,* 

R=^  r-Q'-\-(a.p — la.:p).—.7.su\.Kcos.\.cos.(gv—fv)  ; 
2a^.  (  — j  =4^a.r^Q' — 6.(a.p — la.p),—,y.sin.-K.cos.\.cos.(gv—fv). 

We  have  seen,  in  [5842],  that  the  variation  of  dit  is  nothing,t  even 
when  we  notice  the  square  of  the  disturbing  force  ;  therelore,  the 
coefficient  of  cos.(gv—fv)  must  vanish  from  R.  We  shall  denote  by 
the  characteristic  <5,  placed  before  any  function,  the  part  of  that  fmct  ion, 
which  depends  on  the  oblateness  of  the  earth  ;  and,  we  shall  then  have, 

0  =  5. {r^Q')+(a.p  —l<xp)  .—.-;■  .s\n.\.cos.\.cos.(gv—fv)  ; 


*  (3198)  The  value  of  s  [5946'],  is  the  same  as  in  [4818^,  suppos! Jig  the  origin  of 
gv  to  correspond  to  è  ^  0.  From  tliis  expression,  we  get,  in  2s.smfv  ,  the  term 
y.cos.(gv — ■/«).  Substituting  this  in  [5944],  it  becomes  as  in  [5947]  ;  and,  from  [5945], 
multiplied  by  a,  we  get  [5948];  observing,  that  in  the  terms  whicli  are  connected  with 
ap — |a^,  we  may  put  r=«.  Moreover,  we  have,  as  in  [53479],  /^l+TTWiJsi 
g  =  l+?bo  J  nearly;  so  that  the  angle  gv — fv  is  very  small  in  comparison  with  v; 
the  mean  increment  of  gv — fv  in  a  given  time,  being  the  same  as  that  of  the  longitude 
of  the  moon's  node  [538Sc],  and  g — -/  is  of  the  order  m~  [4S28e],  or  of  the  same 
order  as  the  disturbing  force  of  the  sun  upon  the  moon  ;  consequently  the  factor  m'.{g — •/) 
which  occurs  in  dR  [5949f],  must  be  considered  as  of  the  second  order,  relative  to  the 
powers  and  products  of  the  disturbing  forces. 


751 

[5946'] 

[5947] 

[5948] 
[5948'] 

[5949] 

Symbol 

0. 

[5950] 

[59470] 

[59476] 
[5947c] 

[5947rf] 
[5947  e] 

[5947/] 


t  (3199)     The    secular  variation  of    d.SR,     or  of    dfi     vanishes,  as    is   shown  in     [5949a] 
[5844  line  2, 5794",  &ic.],  noticing  the  terms  of  the  order  of  the  square  of  the  disturbing 
forces.      Now  the  secular  inequalities  are  those  which  are  independent  of  the  configuration  of    [594961 

the  heavenly  bodies;  that  is  to  say,  they  depend  on  the  variations  of  the   elements,  or  on 
the  motions  of  the  nodes,  perihelia,  inclinations,  &.c.,  as  in  [4242 — 4251, &ic.]  ;  and  as  the 
angle     gv—fu  represents  the  longitude  of  moon's  node  [5947rf],  it  partakes  of  the  nature    [5949c] 
o  f  the  secular  quantities,  being  similar  to  those  in  [5846«],  which  are   represented   by  the 

angle     gt-\-j2 ,     applied  to  the  moon's  orbit.     If  we  notice  only  the  terms  of     R     [5881 1 

which  depend  on  the  angle     gv — fv,     we  may  put  it  under  the  form. 


R  =  m'.F'.  cos.  (gv  — fv)  ; 


[5949d] 


752  APPENDIX,  BY  THE  AUTHOR  ;  [Méc.  Cél. 

hence  we  deduce,* 
[5951]  &  .  )  2a^.  [-T'j(  =  — 10.(ao — ^ap).— .7.sin.X.cos.X.COS.(^t)— ^). 

We  shall  now  resume  the  expression  of    d=     [5784], 

[5952]  d^  = -^ .(l—^l-e^).{^~^+2a^^—yndt. 

It  is  evident,  that,  if  we  neglect  the  excentricity  of  the  orhit,  we  shall 
have,t 

[5953]  ds  =  2«^  (--\ndt  ; 

therefore,  by  noticing  only  the  cosine  of  the  angle  gv—fv,  and  substituting 


whose  differential,  relative  to     d ,     is, 

[5949e]  dR  =  —  n.  (g  —  f)  .  F'.  sin.  {gv  —fv  )  .  dv; 

[5949/]  and,  as  the  factor  m'.  {g — /) .  F',  is  of  the  second  order  relative  to  the  disturbing  forces 
[5947/],  it  must  vanish  from  dR  [5949«]  ;  therefore  we  must  put  F'  =  0  ;  and 
then  the  expression  of  ït  [5949rf],  becomes  /?  =  0.  Substituting  this  in  [5947], 
and  retaining  in  r^  Q',  the  part  ^-(''Q')  [5949],  corresponding  to  the  angle 
fgi}  — fo^j^  vve  get  [5950]  ;  observing,  that  the  co-ordinates  of  the  moon  produce  in  r^Q'^ 
terms  depending  on  the  angle  gv — Jv  ,  in  the  same  manner  as  arguments  of  similar 
forms  appear  in  the  expressions  of  the  moon's  mean  motion  and  parallax  in 
[5220,  5331,  &ic.]. 

*    (3200)      If  we   retain,  in    [594S],   only  those  terms   which    depend  on  the  angle 
(gv—fv),     and  use  the  sign     6,     as  in  [5949],  we  shall  get, 

[5951a]  S  .}  2a2   ^L_  j  (  =  4a.8.(r^q')  —  C.(ap— ia(p)  .  —  .  7.sin.X.cos.X.cos.(^y-/y)  ; 

Adding  this  to  the  product  of  [5950],  by     — 4a,     we  obtain  [5951]. 


[5949g] 
[5949;»] 


[5953a] 


t   (3201)     We  have,  by  development,     1 — \/l—e^  =  2  «^  +  ^c.  ;     substituting  this 

in  the  first  term  of  [5952],  we   find,  that  it  becomes  of  the  order    e;     and  by  neglecting 

terms  of  this  order,  we  get   [5953].     If  we   retain,  in   the   second   member  of  this    last 

[59536]     expression,  the  term  depending  on    the    angle     gv—fv,     which  is  given  in  [5951],  and 

chanse     ndt     into     dv,     as  in  [5378'],  we  shall  get  [5954]. 


VII.Apj).  VI.]   EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.       753 

dv    for    ndt    [5378'],  we  shall  get,  as  in  [5379], 

d;=  — 10.(oL — \<i.^)  .~^.y.dv.ûn.\.co^.\.co^.[gv—fv)     [59536].  [5954] 

This  value  of    ds     [5952,  or  5954],  is  measured  in  the  plane  of  the  moon's 

orbit  ;*  to  refer  it  to  the  ecliptic,  we  must  add  to  it  the  quantity  \'{qdp-pdq)      [5955] 

[5955c].     We  shall  now  determine    p    and    q. 


[5956] 


The  equation, 

s  =7.  sin. ^t'     [5946'], 
may  be  put  under  the  form,t 

s  =  r.cos.(gv—fv).sin.fv-{-}.s'm.(gv—fv).cos.fv.  ^^g^^^ 

If  we  compare  it  with  the  following  expression, J 

s  =  q.  sm.fv—p.  cos.fv,  ^5958^ 

we  shall  obtain, 

p  = —r.sm.(gv—fv)   ;         q=r.cos.(gv—fv).  [59593 


*  (3202)  In  computing  the  value  of  ch  [5784  or  5952],  from  the  expression  [5775'], 
we  have  taken,  in  [5775'line2],  the  primitive  orbit  of  m,  for  the  plane  of  the  projection-  [5955a] 
so  tliat  the  angle  nt  -{- s ,  or  fncit  +  £  [5782, 5793],  is  counted  on  this  primitive  orbit. 
If  we  represent  the  differential  of  this  expression  by  dv  =  ndt  -j-  ds ,  and  put  dv,  for  rwî'ïM 
its  projection  upon  the  fixed  plane  of  the  ecliptic  [3778,  Sic],  we  shall  have,  as  in  [3782], 
dv,  ^  dv-{-h.{qdp—pdq);  so  that,  to  obtain  dv,  from  dv  ,  we  must  add  to  ds  the 
correction     \.{qdp — pdq),  as  in  [5955].  [5955c] 

t   (3'20.3)     We  have     gv  =fv-{-{gv—fv)  ;     hence, 

sm.gv  =  COS. (gv—fv).sm.fv+s\n.(gv—fv). cos.fv     [21]  Int.  [5957a] 

Multiplying  this  by     7,     we    get  the  second  member    of  [5956],  and  this  value  of    s 
becomes  as  in  [5957]. 

f    (3204)     The  expression  [5958]  may  be  deduced  from  [1335'],  by  changing    v    into 
fv  ;  which  is  the  same  as  to  count  the  longitudes  from  the  moveable  equinox,  instead  of  the 
fixed  equinox  [5345]       Comparing  the  coefficients  of    sin./«,     cos.fv,     in  [5957,5958],     [5958a] 
we  get  [5959]. 

VOL.  lu.  189 


754  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél 

From  these,  we  get,* 

[5960]  dp  =  —(g—f).q(lv  ; 

L5961]  dq  =      (g—f).pdv  . 

The  value  of     R     contains  the  term,t 

[5962]  (a.0  —  laj)  .  -—  .  sin.x.  cos.x.  o  : 

a-' 

by  the  equations  [5790,  5791],  it  adds  to  the  value  of     dp     the  term, 

D''    . 

[5963]  — (ap — laç)).  — .Sin.  X.  COS.X.  f/l)  ;  [TcTmofdp] 


*  (3505)     The  differentials  of  [5959]  give, 

[5960a]  dp=  —{g—f).y.cos.{gv-fi!).dv  ;  dq=r—{g—f).y.s\x\.{gv—fv).dv. 

Substituting,  in  the  second  members  of  these  equations,  the  values  of    p.,     q    [5959],  we 
get  [5960,5961]. 

t  (3206)     Substituting   for     Y.cos.(gv — •/»),     its   value    q    [5959],   in  the  last  term 
of     R     [5947],  and  retaining  only  this  part  of    /?,     we  get, 

[5963a]  iî  =  (oLp— la(p)  .— .sin.X.cos.X.y      [5962]. 

This  is  to  be  substituted  in  [5790,5791],  as  the  most  important  part  of  R    corresponding 
to  the  values  of    dp,     dq,  now  under  discussion  ;   the  other  parts  having  the  small  factor 

—,     which  is  contained  in     r^Q'     [5944r7,  6].       Its  partial  differentials  relative  to    p,    q, 

give, 

[5963t]  (^— j  =0  (;^;  =  (ap-^a^).— .sm.X.cos.X. 

Substituting  these,  in  [5790,5791],  we  get, 

andt     ,  ,      ^    i)3    .  ,  „ 

[5963c]  dp  =  —  -;==g.(ap— Jao)  .  — .sm.X.cos  X   ;         dq  =  0  . 

Neglecting   terms  of  the  order     e^,     and   changing     ndt     into     dv     [5953i],   we  find, 
that    this    term   of    dp     becomes  as  in  [5963].     Adding   this    part   of    dp     to    that   in 
[5963d]     [5960],  we  get  [5964]  ;     dq     [.5961]  is  the  same  as  in  [5965],  not  being  altered  by  the 
term     dq=0     [5963c]. 


VII.App.§4.]   EFFECT  OF  THE  OBLATENESS  OF  THE  EARTH.        755 

then  we  have  the  two  equations, 

D- 

dp  =  — (^— /)-'y^^i' — ("^-f — 2"-^)  •  "i"  •  sill-  ^  •  COS.  X.dv  \  [5964] 

dq=        (g—f).pdv.  '  [5965] 

These  equations  give,  in  the  expression  of    q,     the  constant  term* 

—^ ■-^.  — r-  .sin.  X.COS.X        r5965fZ]    .  (CoDslam  pan  of,]  [5966] 

g—f      «^ 

From  this  we  obtain,  in  the  latitude     s,     the  inequality, 

*  (3207)     Taking  the  differential  of  [5965],  supposing     dv     to  be  constant,  we  get, 

ddq  =  (g—f).(Jp.dv.  [5965a] 

Substituting  the  value  of    dp     [5964],  dividing  by     dv^,     and  reducing,  we  obtain, 

0  =  ^+(S-— /f  •?+(,?— /)-(<^P-W)--^'-sin.X.cos.X.  [59656] 

This  equation  is  of  the  same  form  as  in  [865«,  870'],  changing  y,  t,  a,  b,  <p,  &c., 
into  5',  V,  g — f,  y,  0,  &c.  respectively  ;  by  this  means,  we  obtain  from  the 
integral  [8656,871]  the  following  expression  [5965f/],  which  satisfies  [59656]  ;  as  is  easily 
proved  by  substitution  and  reduction,  by  mere  inspection,  if  we  take  separately  into 
consideration  the  two  terms  of    q  ; 

q  ^  y. COS. (gv—fv)— —-  .  — -.sin.X.cos.X.  [5965rf] 

g-f        «^ 

The  differential  of  this  value  of  q,  being  substituted  in  the  first  member  of  [5965], 
and  then  dividing  by      (g — f).dv,     gives, 

P  =  — y.s'm.igv—fv),     as  in  [5959].  [5965c] 

Multiplying  [5965f/]  by  s'm.fv,  and  [5965e]  by  — cos.fv;  then  taking  the  sum  of  the 
products,  and  reducing  the  factor  of  y,  by  means  of  [5957»],  we  obtain  the  value  of 
the  second  member  of  [5958],  or  the  expression  of    «  ;     namely, 

•5  =  7-sm.gv -— .  — -.sm.X.cos.>..sin./f.  \5965n 

g—f       «^ 

The  term  depending  on     a" — |o,a),     being  represented  by    ôs,    is  as  in  [5967]  ;     and  if 

we  change  the  divisor     g — ■/    into    g — 1  ;    /    being  nearly  equal  to  unity  [5947c]  ;    it     [596.%] 

becomes  as  in  [5351]. 


756  APPENDIX,  BY  THE  AUTHOR  ;  [MécCél. 

|-5967]  is  =  —  ^-! — - —  .  —  •  sin.x.cos.x.sin./j;     [596q/ J  ; 

which  agrees  with  the  result  in  [5351]. 

The  constant  part  of  q    [5966]  produces,  in  the  function    ^.(qdp — l)dq), 
the  following  term,  as  in  [5385]  ;* 

[5969]  è-C^-P — 2^?)  •— ^•7-sin.x.cos.  A.  cos.(o-« — -Jv),dv. 

[59691     Putting,    therefore,     de^      equal  to   the    preceding  value  of    di,     referred 
to  the  ecliptic,  we  shall  have, 

[5970]  ds^  =  —  ^.(o-p — la.D^.—.7-s'm.>..cos.x,cos.(gv—fv).dv  ; 

which  gives,  in     s^ ,     and,  therefore,  in  the  moon's  motion  in  longitude,  the 
inequality, 


*  (3208)     Multiplying  the  expressions  [5964,  5965]  by  J7    and     — Ip,    respectively, 
and  adding  the  products,  we  get, 

[5968a]  i-{Q<^V—'P^9)  =  —h-(g—f)-(j>^+q^}-dv—i.{o.c—o.(p).—.sin.Xcos.-k.qdv. 

Taking  the  sum  of  the  squares  of    q,     p     [5965f/,  t],  and  neglecting  terms  of  the  order 
(a — o-<p)^,     we  get, 

.,       „         „      2.(ap— a?))     D^       .  ,         j- ^ 

[59686]  V  +q  =  T -^rZf — •  -^  •y-sin.X.cos.X.cos.(g-ti— ». 

Substituting  this  in  [5968a],  and  retaining  only  the  terms  depending  on     (ap — a(p),     we 
get, 

r5968c]      h-il^^P — J>dq)^={^p —  aq)).-j-.y.sin.X.cos.X.cos.(^ti — fv).dv — ^-(o-p — ttçj).  —  .  sinX.cosX.çrftj. 

r.5968rf]     We  may  put     ç  =  7.co3.(^'-» — fv)     [5965(Z],  in   the  last  term  of  [5968c],  and  then  we 
shall  have,  as  in  [5969], 

[5968e]  ^.(çf/p—pf/ç)^  J. (ttp—a(p).—  .y.sin.X.cos.X.cos.(^«— /()).</«;. 

This  value  of    ^.{qdp—pdq)     is  to  be  added  to     ds    [5954],  as  in  [5955],  to  obtain  the 
[5968/]     quantity  which   is  called     rfs,     [5969']  ;    and  the  sum   evidently  becomes  as  in  [.5970]. 
Its  integral  gives  the  term  of    s,,     or     &v     [597 1  ];  which  agrees  with  that  in  [5387]. 


5973] 


VlI.App.  v^^ô.]  GREAT  INEQUALITIES  OF  JUPITER  AND  SATURN.  757 

6v  =  —  13^. -^:i^\-i.— -.--.sin.x.cos.x.sin.C^-i; — fv).  [5971] 

-       g-j       «2 

This  result  is  wholly  conformable  to  that  in  [5387]. 

Lastly,  the  luiictiou  R  being  indeterminate,  the  preceding  differential 
expressio7is  of  the  elements  of  the  orbits,  can  also  be  used  to  determine  the  [5972] 
variations  they  suffer,  either  by  the  resistance  of  an  ethereal  medium,  by  the 
impulsion  of  the  sun'' s  light,  or,  by  the  change  which  the  course  of  tim,e  may 
produce  in  the  masses  of  the  sun  and  planets.  It  is  only  necessary,  for 
this  purpose,  to  determine  the  function  R,  which  results  from  it,  by  the 
considerations  explained  in  chap,  vii,  of  the  tenth  book*  [8884 — 9036]. 

0.\  THE  TWO  GREAT  INEQUALrPIES  OF  JUPFrER  AND   SATURN. 

5.  In  the  theory  of  these  inequalities,  given  in  the  sixth  book,  we  have 
noticed  the  fifth  powers  of  the  excentricities  and  inclinations  of  the  orbits. 
But  it  has  been  discovered,  that  the  values  of  A^^"',  N^'\  &c.  [3860-3860''^]  [5974] 
are  taken  with  a  wrong  sign  [386f)rt,  &c.].  To  correct  this  mistake,  we 
must  change  the  signs  of  this  part  of  the  inequalities.  This  can  be  done,  by 
adding  to  the  expression  of  the  mean  longitude,  which  is  given  in  the  eighth  [59751 
chapter  of  the  tenth  book,  the  double  of  this  part,  taken  with  a  contrary  sign. 
This  part,  for  Jupiter,  is  as  in  [4431,4430a]  ; 

6V'''  =      (12',536393— ï.0',00I755).sin.(5?ï^i— 2n''i+5=^— 2si')  1 

—  (8',l20963+t.0%004>885).cos.(5n't—2nH-\-5e''—2e")  ;       2 
and,  for  Saturn,  as  in  [4487,  4483e  line  4j  ; 

iv"  =  — (29',144591— <.0',004081).sin.(5n''^— 2w''i+5i'— 2.>)  1 

+(18%879594+L0',0n356).cos.(5n7— 2n-i+53^— 2-=-).        2      ^^^'^^ 
The  addition,  to  the  mean  longitudes  of  Jupiter  and  Saturn,  of  the  double 


[5976] 


*  (.3-209)     This    method  of   finding      %     or     R     [5438],   has   already  been     used 
in  estimating  the  resistance  of  the  earth  and  moon,  from  an  ethereal  fluid  [5672,5673]. 
Similar  methods  are  used  in  ascertaining  the  values  of    R,     in  other  cases,  like  those     [^^^""o] 
which  are  mentioned  in  [5973]. 


VOL.  111.  190 


768 


APPENDIX,  BY  THE  AUTHOR; 


[Méc.  Cél. 


of  these  inequalities  taken  with  a  contrary  sign,  can  affect  only  the  mean 
motions  and  the  epochs  of  these  two  planets.  It  cannot  alter,  except  by 
insensible  quantities,  the  other  elliptical  elements,  deduced  from  the 
observations  made  between  the  years  1750  and  1800  ;  because,  during  that 

[5978]  interval,  the  variations  of  these  inequalities  are  very  nearly  proportional 
to  the  time.  We  may,  therefore,  determine  the  corrections  of  the  mean 
motions,   so  as  to  make  the   double  of  these   inequalities,   affected  tviih  a 

[5979]  contrary  sign,  vanish,  in  1750,  when  t  ==  0,  and,  in  1800,  ivhen  t  =  50. 
Thus  we  find,  by  noticing  the  correction  of  Saturn's  mass,  given  in  chap.viii, 
of  the  tenth  book  [9121],  that  we  must  add  to  the  mean  longitude  q"  of 
Jupiter,  given  in  [9137],  the  function,* 


[5980a] 
[59806] 


[5980c] 
[5980rf] 


[5980e] 


[5980/-] 


[5980fir] 


[5980/1] 


*     (3210)     We  have,  in  [9128,9129], 

n"t-\-i''-  =      S" 45'"  41\5+t. 30"  20"'  56',4  ; 
nH-\-i'-  =  231''21'"5S%9+^.  jaMS"  I7%1  . 

Multiplying  the  second  of  these  expressions  by  5,  and  the  first  by  — 2  ;  and  then  putting 
llie  sum  of  these  products  equal  to     T,     for  brevity,  we  shall  have, 

T  =  5n^<— 2w'^<+5£>— 26"  =  69"  17"'5'l'',5+^24"' 32",7. 

Now,  if  we  double  the  expression  of  (hi'"  [5976],  and  change  ils  sign,  as  in  [5978]  ; 
then  decrease  the  result,  in  the  ratio  of  19,232  to  20,232,  on  account  of  the  change  in 
the  estimated  value  of  the  mass  of  Saturn  [9121],  it  becomes, 

1  n  030 

_2x^;-.(12',536393— i.0%001755).sin.r 
+2  X  ^^  .  (8%  1 20963 +i.0',004885)  .cos.  T  ; 

the  terms  A"  -\-  B'^t,  being  added  so  as  to  make  the  expression  vanish  in  1750,  and  in 
1800,  when  t  :=  0 ,  and  ^  =  50,  as  in  [5979].  To  obtain  the  vakies  of  A'",  E'\ 
we  must  first  put  f  =  0  in  [5980c],  and  we  shall  get  the  value  of  T  corresponding 
to  this  time.  Substituting  this,  and  <  =  0,  in  [5980e],  then  putting  the  result  equal  to 
nothing,  as  in  [5979],  we  get  the  value  of  A'".  Again,  with  t  =  50,  we  get  a  new- 
value  of  T  [5980c];  substituting  these  expressions  of  ^,  T,  Jl"',  in  [59S0(?],  we 
obtain  bOB'",  from  which  B"  may  be  determined.  The  result  of  this  calculation 
agrees  very  nearly  with  that  in  [5980]. 

In  like  manner,  if  we  multiply  the  expression  [5977]  by  2,  and  change  its  signs,  adding 
also  the  terms     jJ''-\-B't,     we  shall  obtain  the  formula    [5981].     Having  computed   the 


VII.App.§5.]     GREAT  INEQUALITIES  OF  JUPITER  AND  SATURN.  759 

âç'v=        16',84+^.0%1347  1 

—(2S%S4.—t.0%0033).sm.(5n't—2n"t+5=''—2i")  2      [5980] 

+  (15',44+^0',0093).cos.(5/i7— 2ft'''i+5-=^— 2i'^)  :  3 

and,  to  the  mean  longitude     q"     of  Saturn  [9138],  the  function, 

59'  ==  —  41%  19  — <.0',3309  1 

+  (58',304— ^.0%008162).sin.(5n7— 2m''<+5=-'— 2.=")  2      [5981] 

— (37',759-fï.0',022744).cos.(5n'<— 2»''^+5;'— 2-=").  3 


expressions  [5980, 5981],  it  will   be    easy    to    complete    the   calculations  relative  to  the 
observations  of  Ebn  Junis  [5982,  &c.]. 


[5980i] 


It  is  probable,  that  the  coefficients  of  the  function  [5981],  as  well  as  those  of  tlie  other 
inequalities  of  the  motions  of  Saturn,  arising  from  the  action  of  Jupiter,  must  be  increased 
in  consequence  of  an  augmentation  of  the  estimated  value  of  the  mass  of  Jupiter  by  Gauss, 
Nicolai,  Encke,  and  Airy.     The  first  estimate,  made  by  La   Place,  in    [40G5],  is   founded 
on    the   observed   elongations    of   the   satellites,  by    Pound,    and   is     — ^ — .     But    these     [59804:1 
elongations  have  been  lately  observed  witii  much  greater  accuracy,  by  Professor  Airy,  and 
the  result  of  his  measures,  given  in  vol.  10,  page  404,  of  the  Astronomische  JVachrichlen 
makes  the  mass     — —  .     Nicolai,  by  the  observations  of  the   perturbations  of  Juno,  gives      [5980/1 
iM^-     Encke,  by  those  of  Vesta,     j^^^;^  ;  and  by  the  perturbations  of  the  comet  which     [5980m] 
bears  his  name,      j^^  .    All  these  observations  indicate,  that  the  mass,  assumed  by  La  Place, 
is  too    small   by  about    i\    part  ;  and   tliat   the    perturbations  of   Saturn,   and  several   of    [5980nl 
the  other  planets,  require  some  correction  on  this  account.     On  the  contrary,  the  calculations 
of  Bouvard,  from  numerous  observations  of  the  perturbations  of  Saturn  and  Uranus,  make 
the  mass  equal   to      j^^ .     The   cause  of  this  difference   must  be  ascertained  by  future     [598O0I 
observations  and  investigations.      Some  have  supposed  this   discrepancy  to  arise  from  a 
difference  between  the  action  of  Jupiter  upon  Saturn,  and  upon  the  other  planets  ;  but  we 
have  nothing,  analogous  to  this,  in  any  known  experiments  or  observations  on  the   effect  of    [59P0p] 
universal  gravitation. 

In  closing  this  volume,  we  may  remark,  that  the  sequel   of  the    work   of  Hansen,  upon 
the  inequalities  of  the  motions  of  Jupiter  and  Saturn  ;  which  is  mentioned  in  [■1458c],  and     ^^^^^l] 
also  the  work  on  the  lunar  tlieory,  by  Plana  and  Carlini,  [4752r(],  have  not  been   received 
in  this  country  at  the  time  of  writing  this  article.     We  must  therefore  defer  any  notice  of    I^'^^^^'"] 
these  works  in  the  present  volume. 


760  APPENDIX,  BY  THE  AUTHOR;  [Méc.  Cél. 

These  corrections  have  the  advantage  of  making  the  formulas  of  the  motion 
of  Jupiter  and  Saturn,  given  in  the  above-mentioned  chapter,  agree  better 
with  a  very  important  observation  of  Ebn  Junis.  This  observation,  reduced 
to  the  meridian  of  Paris,  took  place  the  31st  of  October,  1007,  at  3*50'". 
These  formulas  give  729'  for  the  excess  of  the  geocentric  longitude  of 
[5983]  ga,turn  over  that  of  Jupiter,  at  that  time  ;  and  the  Arabian  astronomer 
found  it,  by  observation,  to  be  1440'  :  the  difference  being  71  P.  The 
preceding  corrections  increase,  by  388',  the  excess  of  the  longitude  of 
Jupiter  over  that  of  Saturn;  consequently,  the  new  computation  corresponds 
more  accurately  with  the  observation,  by  that  quantity  ;  and  the  difference 
is  reduced  to  nearly  five  sexagesimal  minutes  ;  which  is  much  less  than 
the  error  to  which  this  observation  is  liable. 


APPENDIX,  BY  THE  TRANSLATOR. 


We  shall,  in  this  appendix,  point  out  some  of  the  important  improvements  made  by 
Gauss,  Olbers,  and  others,  in  the  calculation  of  the  orbit  of  a  planet  or  comet,  moving  in 
an  ellipsis,  parabola  or  hyperbola;  with  the  methods  of  computing  the  place  of  the  moving 
body,  at  any  time,  by  means  of  several  auxiliary  tables.  For  the  sake  of  convenient  [5984] 
reference,  we  shall  insert  in  the  tables  [5985,5986,5988],  the  most  important  theorems, 
relative  to  this  subject,  which  have  been  already  introduced  in  the  preceding  part  of  the 
work  ;  together  with  several  new  formulas,  given  by  Gauss,  in  his  Theoria  Motus  Corporum  (i) 
Cœ/cs^iMm,  conforming,  however,  to  the  notation  generally  used  by  La  Place,  in  this  work. 

In  the  demonstrations  of  the  formulas  included  in  the  table  [59S5lines  1  — 19],  we  shall 
refer  to  any  particular  line  of  it,  by  including  the  number  of  the  line  in  a  parenthesis  ; 
thus,  in  referring  to  the  value  of    c     [5985line  1],  we  shall  use  the  abridged  notation  (1). 


(2) 


From  the  assumed  value  of    e  ^  sin.p     (1),  we  easily  deduce  the  expressions  (2,  3,4)  ;  ,3) 

observing,  in  the  formulas  (3),  that  the  development  of     |\/l-|-e  =F  \/]_e|2     becomes,  by  (4) 

reduction,  equal  to    2  =F  ~-\/\  —  t~  =  2  ^  2. cos. 9  ;     and,  that,  (5) 

4.sin.^Jip,        2 -j- 2. cos. (p  ^  4x03.^^9      [1,0]  Int.  (6) 


The  expression  of  p  [378s],  is  the  same  as  in  (5)  ;  those  of  D ,  a  (6),  are  as  in 
[681"].  The  second  and  third  values  of  p  (5),  are  easily  deduced  from  the  first,  by 
using  p,  D  (1,6).  The  formulas  (7,8,9),  are  as  in  [606],  using  the  second  of  the 
expressions  (4).  The  first  of  the  formulas  (10),  is  the  same  as  in  [603]  ;  the  second  and 
third  values  are  obtained  by  means  of  (5).  The  expression  of  cos. m  (I  !),  is  the  same 
as  in  [603i]  ;  and,  from  this,  \\e  easily  obtain  the  value  of  cos.i;,  in  the  same  line.  The 
first  expressions  of  sin.lw,  cos.\u  (J2,13),  are  the  same  as  in  [1,  6]  Int.  The  second 
values  in  these  lines,  are  deduced  from  the  first,  by  the  substitution  of  the  formulas, 


(7) 
(8) 

(9) 
(10) 


,  zp  eos.u  =  ii^^Ml^i^)       [603&line.5],  Ot, 

l-(-e.cos.r 

and  putting     ^.(1  —  cos.d)  =  sin.^iw  ,     J  .  (  1 +cos.  «)  ^  cos.^^d    [1,6]  Int.     The  third     (is) 

VOL.    III.  191 


762 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5964] 


(13) 


expressions  are  deduced  from  the 
second,  by  the  substitution  of 

' =--    (10); 

l-|-e.cos.j;         p 

the  fourth,  or  last  of  these  values, 
is  deduced  from  third,  by  the 
substitution  of 

jp=:a.(l  — e^)      (5). 

The  last  of  the  formulas  (14), 

is  the  same  as  in   (8);  and  the 

second  is  deduced  from  this  by 

(15)     using    the    value    of    tang.(45'' — |(p)      (4).     Multiplying    together    the   last    values    of 

(15)     sin. Am,  cos. ^u    (12, 13),  reducing  by  means  of  [31]  Int.,  and  using    ^/l  — e^  ^cos.9  (I), 

we  get  the  last  expression  (15)  ;  the  second    expression  (15),  is   deduced  from  this,   by 

M7>     usin2     ==  — -     (5).     The  first  of  the  formulas  (16),  is  deduced  from  tiie  first  of 

'"'  "      a.cos.ij]  P 


(14) 


(15);  then  substituting  p  =  t/.cos.^ç),  and  ^^=«.cos.<p,  we  get  the  third  and 
fourth  expressions  in  that  line.  Multiplying  together  the  first  values  of  r  and  cos.v 
(9,  1 1),  we  get  the  first  expression  of  ?-.cos.'v  (17)  ;  substituting  e  =  sin.ç,  or  rather 
_  c  =  cos.(90''+ç))  ,     we  get, 

cos.  M  —  e  =  COS.  w  +  cos.  (90"'+  9) 

=  2  .cos.{iu  4-i<p+45'').cos.  (^M  — *(?  —45'')     [27]  Int.; 

whence  we  easily  obtain  the  last  expression  (17).  Multiplying  the  third  value  of  cos.J?< 
(13),  by  sin.|« ,  and  the  third  value  of  sin.^M  (12),  by  — cos.iu;  then  taking 
the  sum  of  the  products,  and  reducing,  by  means  of  [22,31]  Int.,  we  obtain, 

sin.  I  .(r —  m)  =  |sin.D  .  1/    L  •  \^i  -\-  e  —  \/l  —  e]  ] 

substituting  the  first  of  the  formulas  (3),  we  get  the  first  of  the  expressions    (18)  ;  and,  by 

(24)     using  the  value  of    sin.r  =:  VP"-^'"'"     (16),  we  obtain  the  second  of  the  formulas  (S). 

If  we  repeat  this  last  calculation,  changing  the  factor  — cos.iw,  into  -f  cos.Ji; , 
we  get, 

sin.J.(i'4-w)  =  ism.v.X/    L  .l^rfe  -f  ^r^e], 

and  by  using  the  second  expression  (3),  we  get  the  first  formula  (l9)  ;  then,  substituting 
the  preceding  value  of    sin.v,     we  get  the  second  of  the  formulas  (19). 


(18) 
(19) 
(20) 

(21) 

(22) 
(23) 


(23) 


FORMULAS  IN  AN  ELLIPTICAL  ORBIT. 


763 


FORMULAS  IN  AN   ELLIPTICAL  ORBIT, 
e  -i^  sin. 9  ;  \/(l c")  =  COS.O  ;  [ExcenHicity  t] 

1— c  =  2.sin.2(45''-J?)  =  2.cos.3(45''+à(p)  ;     I4-e=2.cos.2(45''4(p)=2.sin.2(45"+J<!))  ; 
v/(l+e)-v/(l— e)=2.sin.*<p  ;         ^Çl^e)-^\/(l—e)  =  S.cos.^?  ; 

1=^=  tang.2(45''— I?)  ;  J±^  =  tang.2(45''+iç>)  ; 

p  =;  «.(1 — e^)  =  «.cos.^(p  =  (l-j-e).J)  ; 
D  =  a. (I — e)  =  aa.  ;         a.  =  1 — e  ; 
n<  =  u — e.sin.M  ; 

tang.Jt)  =r  »  y/f  — ^Ytang.jM  =  tang.(45''+è'p).tang.jM  ; 

r  =  a. [I — e.cos.w)  ; 

n.(l — e2)  a.cos.2?  p 


l-}-ecos.«  l-}-e.cos.u  l-(-f.cos.u    ' 


COS.U   = 


C03.U — e 
1 — e.cos.ît 


COS. M 


e-|-cos.« 


l-[-e.cos.«   ' 

iu=\/h.(l — cos.u)=s\n.iv.( )  =s'm.^v.[- )  =sin.it'-l — ~ —  1  : 

2    ^  ^  ^  '  \l+e.cos.vJ  \      P      /  ^     \a.(l+e)/  ' 

.Au=n/*^Cl+cos.M)=cos.Jy.( ,-: y=cos.|«.{   '■ -)  =COS.U'.(  ^- Y; 

tang.iM  =  tang.Jj;.tang.(45''— ^<p)=  iy^^^-^j.tang.iu  ; 


sin 


cos 


sin. M 


r.sin.îJ 


r.sin.D.cos.ç         r.sin.î) 
p  a.cos  (? 

p.sin.14 


cos.ip 


a.cos.ip.sin.M  =K/pa.s'm.u  ; 


[5985] 
(1) 

(2) 

(3) 


r  Paramotcr    9p 

(5) 

rPorihelion  distance  D 

1       (6) 

[Mean  anomaly  ni 

(7) 

rTime  from  Perihelion    (. 
|_        cxpressetl  in  days 

(8) 

fExcentric  anomaly  \l 

(3) 

[Radiu^t  vector  r 

(10) 

Elliptical 
formulas. 

[True  anomaly  v 

(11) 

Y    >•    V. 

(121 

r.cos.i'  =  «.(cos. M — e)  =  2a.cos.(jM+^(p-|-45'').cos.(^M — |(p — 45'')  ; 
sin.  J.(t) — u)  =  I    y  -  .  sin.|?.sin.D  =  i    /  -  .  sin.|?).sin.M  ; 

sin.5.(i;-|"w)  "^  I  /    ~  .cos.5(p.sin.«=  *    X  -  .  cos.jp.sin.w. 


(13) 
(M) 

(15) 

(16) 
(17) 
(18) 

(19) 


764 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5986] 


FORMULAS  IN  A  PARABOLIC  ORBIT. 


(4) 


(5) 


(6) 

Parabolic 
formulas. 

(7) 


(8) 


(9) 


The   equations   of  the  motion   in  a  parabola   [59S61ines2 — 101,  are   the   same  as  in 

[691,693,  &C.J  ;  in  which     2*     represents  the  circumference  of  a  circle,  whose  radius  is 

(1)     unity  [691'"  line  4J,  and    r=365''^J\ 25638,  is  the  length  of  a  sidéral  year  [691'",  750']. 

j  Parameter  2p  1 
fPejihelion  distance  Z>1 


FRadius  vector   r\ 
[True  anomaly    v  J 


(2) 

p  =  2D  ; 

(3) 

D  =  ip  ; 

D 

COS.Siî)  l-(-cos.w     ' 


* .  V/2"  ' 


nh' 


tang.|t)-|-^.tang.»Jr} 


tang.|î)+i.tang.3J«J 


=  j-ltang.èu+^.tang.^ét)} 


"  Time  from  the  Peiihelion    f, 
expressed  in  d&^a 


] 


[Time  from  tho    "1 
periiielion  t'  daye,  I 
when   B=J.      J 


(10) 


3 

B^ 


[5987]  In  the  expressions  of    t     [5986  lines  5,  8],  we 

(1)  ought,  in  strictness,  to  change  T  into  T.y/i-f-ni"  ; 
m"  being  the  mass  of  the  earth,  and  1  the 
mass  of  the  sun  j  this  is  evident  from  [692',  &ic.], 

(2)  where  |j.  =  l-|-m".  It  is  common,  however,  to 
neglect  the  mass  m",  as  we  have  already 
observed  in    [692'  line  4].       Instead   of     T,     or 

2ir 

(3)  rather     T.\/l-|-m",     the    symbol     ^=fVT^" 

is     used     by     Gauss,     and     by      most     of     the 
(4,    German  astronomers.       We  have   already  found, 
in  [750'], 

T 


T 


(5) 


127 


=  9'i-y% 688724...,       or       log.-^  =  0,98626669...  ; 


FORMULAS  IN  A  PARABOLIC  ORBIT.  765 


and,  by  neglecting    m",    we  have,  [59871 

(6) 


2x  ,       ,         ,       St 


fc=— ,     or     log./.  =  log.-f^  8,2355820...; 


but,  if  we  notice  m",  we  shall  get 


to^"-) 


log.fc.\/ï+^'  =  log.^  =  8,2355820...  ; 


(7) 


(10) 


and,  since     log.^l-j-m"  ^=  0,0000006... ,     we  shall  obtain  the  corrected  value  of, 

log.fc  =  8,2.355814...  ;  (8) 

being  nearly  as  it  is  given  by  Gauss,  in  his  Theoria  Motus  Corporum  Cϔestium  ;  differing 
from  the  former  expression,  by  the  very  small  fraction  0,0000006...  We  may  remark, 
that  the  mean  angular  motion  of  any  planet,  in  the  time  t,  is  represented  in  [605",  605'J, 

by     nt  =     '^  ^"^     ;     m  being  the  mass  of  the  planet  ;     a    its  mean  distance  from  the     '■^' 

a* 
sun  ;  that  of  the  earth  from  the  sun  being  taken  for  unity.  The  second  member  of  this 
expression  must  he  multiplied  by  a  constant  quantity,  which  is  the  saine  for  all  the  planets,  to 
reduce  it  to  the  unit  of  the  measures  of  these  angles.  To  ascertain  this  quantity,  we  shall 
observe,  that  the  mean  angular  motion  of  the  earth  in  a  sidéral  year  T,  is  represented 
by  the  whole  circumference  2*  [691'']  ;  and,  if  we  change,  in  the  second  member  of  (U) 
[5987(9)],     t,     m,     a     into     T,     m",     1     respectively,  it  becomes     T.y/l^^.      To 

2* 
reduce  this  to     2c     [598T  (1 1)],  we  must  evidently  multiply  it  by     w,    .         =-,     or  by 

the  quantity  Jc  [5987(3)];  which  therefore  represents  the  constant  quantity  [5987(10)]  ; 

hence  the  mean  motion  [5987  (9)]  becomes  nt='   ^      "  ;  consequently  n=    ^     '"''.    „2) 

«^  ai 

This  value  of   n    must  be  used  in  [5985  (7)].      If  we  wish  to  express  the  mean  motion  in 

secondsjwe  must  multiply  the  expression  of  nt  [5987(12)]  by  the  radius  in  seconds  206264',67;     (i3) 
or,  to  avoid  this  labor,  we  may  use  the  value  of  A."  in  seconds  ;  namely,  A,"  ^3548', 18761 
or  log.A-^ 3,55000657.     In  estimating  tlie  motion  of  a  comet,  we  may  neglect  its  mass    (H) 
VI,  on  account  of  its  smallness  ;     and  tlien  the  expression  of  the  mean  motion  [5987  (12)] 

becomes     — .       This   is    expressed  in  [702']  by      -^^  ;     the    accent     on     n'     being     (is) 

omitted,  to  conform  to  the  present  notation.  Hence  it  appears,  that  we  must  put  y/jji  =  k, 
to  reduce   the  formulas  of  the  author,  in  [702',  &c.],  to  the  notation  of  this  article. 


(16) 


The  expressions  in  [5986  lines  2,  3]  are  the  same  as  in  [807',  807"].     The  first  formula 
in   [5986  (4)],  is  the  same  as  in  [691  line  1]  ;    the  second  expression  is  easily  deduced     (17) 
from  the  first,  by  the  substitution  of 

cos.^iw  =   J  -)-  i  .  cos.  V  , 
VOL.  III.  192 


766 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5987]      and    the  value  of    D     [5986  (3)].      The  expression  of    t     [5986  (5)],  is  the  same 
as  in  [693].     Substituting  in  this,  the  value, 


(18) 


T  = 


[5987  (6)], 


(19) 

(20) 
(21) 

(32) 


we  get  [5986  (6)].  This  expression  of  t  may  be  put  equal  to  V^  t'  [693a], 
as  in  [5986(7)];  t'  being  the  time  from  the  perihelion,  corresponding  to  the  anomaly 
V,  in  a  parabolic  orbit,  whose  perihelion  distance  D  is  equal  to  unity.  This  parabola 
is  usually  called  the  parabola  of  109  days  ;  because,  it  requires  about  109  days  to 
describe  an  arc  of  90'^    from  the  perihelion,  in  a  parabola  whose   perihelion  distance  is 

unity.  Dividing  the  three  expressions  in  [5986  (5,6,  7)],  by  D^,  we  get  the  formulas 
[5986  (8, 9, 10)].  From  that  in  line  8  or  9,  Burckhardt  has  computed  Table  III,  of  this 
appendix,  changing     v    into    U;    and  putting, 


3!r.v/2 


_    27day3^  4038.. 


Then,   by  means  of  this  table,  we  can  find,  by  inspection,  the    anomaly     U,     or     v, 
from   log.  t',    or  the  contrary. 


FORMULAS  IN  A  HYPERBOLIC  ORBIT. 


[5988]  The   formulas  for  computing  the  motion  of  a  body,  in  a  hyperbolic  orbit,  are  given  in 

[702]  ;  but,  it   will   be    convenient  to  alter  the  forms   of  these  expressions,  by  writing 
(1)     o    for    a',  and  introducing  the  auxiliary  quantities    >f,    m,  proposed  by  Gauss  j  so  that 


(2) 


e  .  cos.^  =  1, 


and 


u  =  tang.(45''4-i«)  ; 


by  this  means,  we  obtain  the  following  system  of  equations,  corresponding  to  the  motion 
in  a  hyperbolic  orbit. 


is 
I 


S 

^ 


si 
t9 


FORMULAS  IN  A  HYPERBOLIC  ORBIT.  767 

e_i  [rm8] 

e  ==  —,  =  secant4-=v/i+tan!T.s4.;     \/î2ZT=  t&ng.^;     j-p-=tang.2è4.;  [ExcentncUyeJ  o) 

^   =a.(e^— l)  =  rt.tang.=»4-=  (e+l).D;                                                                                             [Parameter  2p]  (4) 

D=  a.{e—l)  =—aa.;             a=— (c— 1);                                                                        [perihelion  distariceC]  (5) 

— -.t    =  e.tang.a liyp.log.  tang.(45''-j-2-ro)   ;                                              [Semi-transvorso   axis  o]  (6) 

^K                                 (m  11                                                      //icdl    1      N                    rTiine  from  tlie  perihelion  (,"I  ,.. 

— J.  ^    =    iXe.-i ^ common  log.  tang. (45  +Jro)   ;                [         expressed  in  days         J  (7) 

a*  « 

X  =  0,4.3429448...  ;     log.x  =  9,63778431 13...  ;     log.Xfc  =7,8733657527...  ;  (S) 

fc  =          7     -^^  =  0,01720209895  parts  of  radius  ;     log./c=8,2355814414...  ;  (9) 

J-  -y  l-\-7n" 

tang,  ^-a  ^  I    /  (  —  Vtang.^r  =  tang.^^/.tang.^u  ;                                      [Auxiliary  angia  a]  (loj 

p  a.[t- — 1)  ^.cos.sj^ 


l-j-e.cos.«  l-f-e.cos.u  2.cos.fs(t) — 4').cos.à(r-^-^],)    ' 


j  Radius  vector  r\ 


(IJ) 


r  =:  a.  ( —  1  )  =  ^a .  ■;  e  .  I  w  +  -  1  —  :^  >  ;  (i2) 


.rf_l_j    >,  ]-f-tang.  AiTT    _    cos..i(v— 4) 


HyperboJk 
furmulas. 


W    =    tang.(45*+i7.)    =   ^_^^^^l^     =    eoS.4(«+4)      '  [Auxil.ary  ,uant..y  .]        (.3, 

1  1  f      \     ^\  l-l-cos.^.cos.v  e-|-cos.t! 

COS. -51  ^  V  w/  2.cos.è(i'— 4).cos.è(«-(-4)  l+e.cos.u    ' 

«2-1  2m  u2  — 1 

r.  sin.i'  ^^.cot.i/'.tang.'n  :^  a.tang.4'.tang.a 

=  ^p.cot.4-.U—  -j  ==  |rt.tang.+  .^<-  A  ; 


(21) 
C22) 


r.  COS 


768  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5989]  In  the  demonstrations  of  these  formulas  [5988],  we  shall  refer  to  any  one  of  them,  by 

placing  the  number  of  the  line  in  which  it  is  situated,  in  a  parenthesis,  in  the  same 
manner    as    in    the    elliptical   formulas   [5984  (2),  fee.].        From    the    assumed    value 

e   =    (3),    we  set,  by  means  of  [1,6]  Int., 

1— C0S.4  2.sin.2.H  ,   ,  l+cos.X       2x03.244 

(?)  e — 1^ —  =  - — r~  ;  ^+1  — ;"■= r~  '> 

COS.X  COS.n}/  COS.-4  COS.4 

dividing  the  first  of  these  expressions  by  the  second,  we  get  the  third  of  the  formulas  (3). 
In  a  hyperbola,  the  semi-axis  a  becomes  negative,  and  is  represented  by  — a  [698"]  ; 
hence  the  values  of    j),     D     [5985  (5,6)]  become,  in  the  hyperbola, 

p  =  a'.(e2— 1);  D  =  a'.{e—l); 


(3) 


w 


(5) 


(6) 


(7) 


and,  if  we  neglect  the  accent  upon  a! ,  for  the  sake  of  simplicity  in  the  notation,  we 
shall  obtain  the  first  expressions  of  p,  D  (4,  5)  ;  the  others  are  deduced  from  these, 
by  the  substitution  of  ^l,  D  (•^,5).  If  we  change,  in  the  first  equation  [702],  the 
symbol  \/fji.  into  k,  as  in  [5987  (16)],  and  omit  the  accent  on  a,  as  above,  it 
becomes  as  in  (6)  ;  using  hyperbolic  logarithms.     We  must  multiply  this  by 

X  =  0,43429448...     (8), 

when  common  logarithms  are  used  ;  the  quantity  X  being  the  ratio  of  a  common 
logarithm  to  a  hyperbolic  logarithm  ;  and  then,  (6)  changes  into  (7),  by  the  substitution  of 
tang.ci    (15)  ;  this  value  of    tang.ra     being  deduced  from  the  assumed  value  of    u    (13), 

(8)  as  in  [5989(14)].  The  first  formula  (10)  is  the  same  as  that  in  [702  line  3]  ;  from  this 
we  easily  deduce  the  second  form,  by  the  substitution  of  tang-J^^  (3).  The  first 
value  of  r  (11)  is  the  same  as  in  [3796],  using  p  (4)  ;  and  this  form  is  common  to 
the  other  conic  sections  [5985  (10),  5986  (4)].  Substituting  in  this,  the  first  value  of 
»    (4),  we  get  the  second  form  of   r    (11)-     Multiplying  the  numerator  and  denominator 

(10)  of  the  first  form  of  r  (11),  by  cos.-^,  and  substituting  e.cos.-^- =  1  (2),  in  the 
denominator,  we  find,  that  this  denominator  becomes, 


(11) 


cos.vj.'+cos.v  =  2.cos.|(« — 4')-cos.5(t)+4')     [20]  Int., 

and  we  obtain  the  third  expression  of  r  (U).  The  first  expression  of  r  (12)  is  the 
same  as  in  [702  line  2],  omitting  the  accent  upon  a',  as  above.  To  obtain  the 
second  form,  we  must  use  the  auxiliary  quantity     u     (13)  ;  namely, 

.  =  tang.(45^+i-):=.;±;:-g^     [29]  Int.  ; 
from  which  we  get, 

(.3,  t«"s4-  =  ^    (16)  ; 

and  then,  from  [30']  Int.,  we  have,  as  in  (15), 


(12 


FORMULAS  IN  A  HYPERBOLIC  ORBIT.  769 


_    2.tang.*73     __  \u+U      __         2.(m^— 1)  u^—l 


[5989] 

(H) 


From  this,  we  get, 

sec.TO  =  — ^  =  (l+tang.^ra)i  =   ^^==:  jYm+-Y     as  in  (14,  15).  05) 

Multiplying  together  the  expressions  of    cos.ra,     and     tang.ra     (15),      we  get     sin.* 
(15).     In  Uke  manner,  if  we  substitute  the  value  of    tang.Jw     (16),  in  the  expression, 

cos.J=r  ==   (l+tang.2^^)-i     [34'"]  Int.,  (I6) 

we  get  its  value  (16)  ;  multiplying  together  these  two  expressions  of    cos.^w,     tang.|î;i, 

we  get     sin.|:3     (16).     Substituting  the  first  value  of    (14)  in  the  first  expression 

of    r     (12),     we  obtain  its  second  form.     If  we  substitute,  in  the  second  expression  of 
M    (13), the  value, 

tang.Jra  ==  tang.|4-.tang.|y     (10)  ;  (i8) 

then,    multiply    the   numerator  and   denominator  by     cos.J4'.co3.|«,      we  shall  find   that 
the  numerator  becomes, 

cos.i^^.cosl^J+si^.^^^.sin.l^)  =  cos.i(î) — 4.)  ; 
and,  the  denominator,  ,|9> 

cos.J-J/.cos.^t) — sin.^4/.sin.l«  =  cos.J(«+4/)  ; 

as  in   the  last  of  the  formulas  (13).     If  we  now  substitute  the  last  value  of    m     (13),  in 
the  first  expression  of  (14),  it  becomes, 


1        ^    1     \  cos-i(«— 4-)    ,    cos.j(r+4.)  -i  _ 
cos.a-  ^  '  I  cos.!(i;+4.)        cos.|(î;— 4.)  5  ' 

reducing  these  to  a  common  denominator, 

2.cos.i(t;— 4,).  cos.J('y+4.), 
we  find,  that  the  numerator  becomes,  by  using  [6,  20]  Int., 

cos.2|(o-+)+cos.2|(t;+4-)  =  li+è-cos.(y— 4.)H-{'+|.cos.(«;+v}.)J 

=  1+|.cos.(d— 4)-f|.cos.(jj-f-4-)  =  l+cos.+.cos.D  ; 
as   in   the    second  formula   (14).     Multiplying  the   numerator   and   denominator  of  the 
second  formula  (14)   by     e,     and  substituting  the  values   [5989  (ll)J  and   (2),  we  get     '^'* 

VOL.  III.  193 


(20) 


(21) 


(22) 


770  APPENDIX,  BY  THE  TRANSLATOR; 

[5989]      the  third  formula  (14).     If  we  add     q=l     to  the  last  of  the  values    (14),     and 

(24)  1  r 

substitute     ,  , =-     (11),  we  get, 

l-f-e.cos.K        p 

lq=cos.3r  (e=F]  ;.(l=Fcos.i))  (eTI).(l^cos.D).r 

(25)  =     — =       . 

cos.^  l-|-e.cos.«  p 

If  we  use  the  upper  sign,  and  put 

(26)  1— cos.OT  =  2.sin.®ia- ;         1 — cos.î)  =  2.sin.^iM     [l]Int.  ; 

we  get,  by  extracting  the  square  root,  the  first  of  the  formulas  (17).    If  we  use  the  lower 
sign,  and  put, 

(28)  l_|_C0S.ar    =    â-COS^Ja-  ;  l-(-COS.l'    =    2.C0S.^|«  ; 

we  get  the  first  of  the  formulas  (19).     The  second  of  the  formulas  (17,  or  19),  is  deduced 

(29)  from  the  first,  by  the  substitution  of  p  =  a.{e^ — 1)  (4).  Substituting,  in  the  first 
of  the  formulas  (17,  or  19),  the  values  of  sin.Jji,  cos.iw,  cos.ct  (16,15),  which 
give, 

sin. its  u — 1  cos.^ts        u-\-l 

^/cos.TS         2.\/u  ycoi.zi       2yu 

we  get  the  first  of  the  formulas  (18,20);  finally,  substituting  in  these,  the  value  of 
p=a.(e^ — 1)  ,  we  get  the  last  of  the  formulas  (18,20).  Multiplying  by  two  the 
product  of  the   first  of  the  formulas  (17,  19),  we  get, 

2sin.|-!S.cos.|'ss  p 

cos.w  {/{e^ — 1) 

and  by  substituting, 

2.sin.iu.cos.|«  =  sin.w  ;         2.sin.its.cos.its  =:  sin.-z3  =  cos.ra.tang.a     [3] ,  34']  Int., 

(32) 

also     y/(e^ — 1)  =  tang.4.  =  (cotang.4')~^     (3),  we  get  the  first  equation  (21).      The 
(33;     second  formula  (21  ),  is  easily  deduced  from  the  first,  by  the  substitution  of  j3=a.tang.^4/  (4). 

('*;    Substituting  in  these  two  expressions,  the    value    of    tang.is  =  |.f  h j     (15),  we  get 

the  first  and  second  formulas  (22).  Multiplying  the  second  value  of  r  (11),  by  cos.j;, 
and  reducing,  we  get,  by  using  the  last  formula  (14), 

a.(e^ — l).cos.«  (e-[-cos.v)  1 

(35)  r.cos.'w  =  — ^ — =  «e — a.-- =  ne — a.  ; 

l-J-e-cos.u  l+e.cos.«  cos.ra 

as  in  the  first  expression  (23).  Substituting  in  tiiis,  the  first  value  of  ^^^  (14),  it 
becomes  as  in  the  second  formula  (23) . 


INDIRECT  SOLUTION  OF  KEPLER'S  PROBLEM.  771 

From  the  first  of  the  formulas  (11),  it  appears,  thiit    r    increases  with    v,    and  becomes       [5989] 
infinite,  when 


l+e.cos.i'  =  0,     or     cos.r  ^= =  —  cos. 4^     (.3)  ; 


(37) 


e 


(38) 


(41) 


which    gives     v  =  ISC — 4''     Now    the    radius     ;•,     corresponding   to    a    point    of  tlie 
hyperbola,  at  an  infinite  distance  from  the  hcus,  must  evidently  be  parallel  to  the  asymptote; 
therefore,  the  angle    4^     represents  the  angle  of  inclination  of  the  asymptote   to  tiie  axis. 
Hence    it  is    evident,  that  the  maximum  value  of    v     is  represented  by     180'' — 4^  >     ''nd     (39) 
the  greatest  77!!n«m«?n  value  is     — (ISC' — 4-)  j     moreover,  it  follows,  from  the  last   of  the 

COS.A.f — 4^)  (A(\'\ 

formulas  f  IS),  that  when     v  ^=r.  0       u  ^  ■ ^-rr;  =  '  >     a'la  tli<it  ^  increases  with  v,     ^  ' 

^      ''  cos.i.{-(-4) 

and  becomes  infinite,  when     y  =   ISO''— 4-,     or     \-{y-\-\^  =  OC  .     It  decreases  when 

I'     is  negative,  and  becomes  nothing  at  the  other  limit,   where     v  =  —  (ISO" — 4');     or 

\.(v-\)  =  -  90". 

TO  COMPUTE  THE  TRUE  AXOMALY   FROM  THE  TIME,  OR  THE  CONTRARY,  IN  AN  ELLIPTICAL  ORBIT. 

The  true  anomaly     v,    in  an  elliptical  orbit,  can  be  easily  obtained  from  the  mean  anomaly       (59901 
«t,     by  means  of  the  formula  [<3C8],  in  cases  where  the  excentricity     e     is  so  small,  that 
it  is  only  necessary  to  notice  two  or  three   terms  of  the    series  ;  but    as  the   value   of    e     ''' 
augments,  the  number  of  terms  must  be    increased,  so  that  the   method   finally  becomes 
very  laborious,  and  it  is  much  better  to  use  the  indirect  method  of  solution,  first    o-jven   bv 

■'  ^  a  J        Kepler's 

Kepler,  who  was  the  original  proposer  of  the  problem.     This  method  is   very  simple,  and    '""''''="'• 
has  the  decided  advantage  of  being  applicable  to  all  the  varieties  of  the  ellipsis  ;  but  when 
the  excentricity  is  nearly  equal  to  unity,  it  requires  the  use  of  a   table    of  logarithms,  to 
more  than  seven  places  of  decimals  ;    this  difficulty  is  obviated  partially  in   the   method   of    (2) 
Simpson,  and  wholly  in  the  method  of  Gauss,  which  we  shall  give  hereafter. 


To  illustrate  this  indirect  method  of  solution,  we  shall  apply  it,  according  to  the  precepts 
of  Gauss,  to  the  determination  of  the  true  anomaly  in  an  elliptical  orbit.  We  shall  suppose 
M,  to  be  an  approximate  value  of  u,  and  x  its  correction;  so  that  u  =  u, -{- x  , 
satisfies  the  equation  [.5985  (7)].  We  must  compute  the  value  of  e.sin.w^  in  seconds,  by 
logarithms;  and,  while  performing  the  operation,  we  must  take  from  the  tables,  the  variation 
X  of  the  log.sin.î/,,  corresponding  to  r  in  the  value  of  u^  ■  also  the  variation  fj.  of  the  (S) 
logarithm  e.sin.w^,  corresponding  to  the  variation  of  one  unit  in  the  number  e.sin.w^; 
the  signs  of  X ,  |u,  being  neglected,  and  both  the  logarithms  being  taken  to  the  same 
number  of  decimals.  Now  when  w,  is  nearly  equal  to  u,  or  u^-j-x  ,  the  variations 
of  the  log.  sines  of  the  arcs  from  ?<,  to  u^-\-x,  will,  in  general,  be  nearly  uniform  ; 
hence  we  shall  have,  with  a  considerable  degree  of  accuracy, 


(3) 

(4) 


(B) 


(7) 


■Kx 
c.  sin.  {u^ -\-  x)  =  e.s'm.u^  ziz  —  ;  (8) 


(14) 
(15) 


772  APPENDIX,  BY  THE  TRANSLATOR; 

[5990]      the  upper  sign  being  used  m  the  first  and  fourth  quadrants  ;  the  hiver  sig7i   in   the  second 
(9)    and  third  quadrants  ;  these  signs  being  evidently  the  same  as  those  of  e.cos.w,  [5990(13)]. 
Substituting  this,  and     u  =  u^-\-x ,     in  [5985  (7)],  we  get,  by  reduction, 

(10)  a;  =  .  (lit  —  u,  4-  e  .  sin.  u,)  ; 

Indirect 

solution  of      _« 
Kepler's  ^*  ' 

problem. 

(11)  u  =  ti,-\-  X  =:  nt  -{-  e  .  sin. M,  ±  .  (nt  —  «,  +  e . sin.  ?<,)  ; 

(J,  ^  X 

(12)  in  which  we  must  notice  the  sign  of  the  factor  ±  ■  ^  ,  according  to  the  above 
directions;  and  we  must  also  have  regard  to  the  sign  of  the  other  factor     (nt — !i^-|-c.sin.M,). 

(13)  We  may  remark,  that  the  factor     ±  -  ==  e.cos.w,,     as  is  easily  proved  by  the  substitution 

of    sin.(M,+a?)  =  sin.?<,-fx  cos.m,     [00]  Int.,  in  the  first  member  of  [5990(8)]  ;  and,  as 

e<l,     cos.M,<l,    we  shall  have    (j.>X  ;     tlierefore,     ,7^     has   the   same  sign   as     -. 

If  the  assumed  value  of  u,  should  differ  considerably  from  «,+» ,  we  must  repeat  the 
operation  ;  using  this  computed  value  of  m,+x'  for  a  new  value  of  «,;  and  this  process 
must  be  repeated,  until  the  correct  value  of  u  is  found.  In  most  cases  which  occur  in 
practical  astronomy,  it  will  be  easy  to  assume,  in  the  first  instance,   a   value  of    u^     which 

(^5)  does  not  difier  much  from  v  .  This  is  particularly  the  case,  when  forming  a  table  of  the 
values  of  u,  corresponding  to  the  regular  intervals  of  nt ,  from  0"*  to  360".  If  we 
have  no  means  of  ascertaining  this  first  value  of  w, ,  we  may  make  the  first  computation 
in  a  rough  manner,  using  small  tables  of  logarithms,  to  five  places  of  decimals,  and  to 
minutes  of  a  degree.     It  unll  tend  to  simplify  the  operation,  to  take  for     w,     a  quantity 

''^*  whose  sine  can  be  obtained  frorn  the  tables  by  inspection,  withont  any  interpolation;  as,  for 
example,  by  taking  the  value  of    n^     to  minutes,  when  the  table  of  sines  is  given  for  every 

*^^'    minute  ;  or  for  tens  of  seconds,  when  tlie  tables  are  arranged  for  tens  of  seconds  ;   &,c. 

Useoftho  jn    rnakina:     these    calculations,   and  others  of    a   similar  nature,  it  has  been  found 

letter  II,  "  /•  (•      J        7 

^fth'e  convnnent  to  annex  the  small  letter     n     to   the  last  figure  of  the  logarithm  of  any  factor 

*°'"°°(iO)  which  has  a  nc<ratiue  value  ;  since,  by  this  means,  ive  can  very  easily  ascertain  the  sign 
n"umericai  of  0  quantity,  which  depends  on  the  product  of  a  number  of  factors,  of  different  signs, 
tion.  ^^^  whose  lo"-arithms  are  to  be  added  together,  to  obtain  the  logarithm  of  the  required  number. 
It  beino-  evident,  that  the  sign  of  this  number  must  be  positive,  if  the  number  of  the  letters 
n  be  even,  but  negative  if  the  number  be  odd.  Thus,  in  finding  the  logarithm  corres- 
pondin"- to  the  quantity  —3. sin. 192'',  composed  of  the  two  factors  — 3  and  sin.  192'*, 
we  may  put  for  their  logarithms  the  quantities  0,4771213„  and  9,317S789„  ,  whose 
'■'^^  sum  9,7950002  corresponds  to  a  positive  quantity.  We  must  also  carefully  notice  the 
signs  of  any  quantities,  depending  on  the  sine,  cosine  or  tangent  of  an  arc  ;  observing  that, 
according  to  the  usual  rules,  we  have, 


(20) 
(21) 


INDIRECT  SOLUTION  OF  KEPLER'S  PROBLEM. 


773 


sin.     or     cosec.     is  +  in  the  first  and  second  quadrants  ;  —  in  the  third  and  fourth. 
COS.     or     sec.        is  -j-  in  the  first  and  fourth  quadratits  ;  —  in  the  second  and  third. 
tang,  or     cot.        is   +  in  the  first  and  third  quadrants  ;     —  in  the  second  and  fourth. 

To  show  by  an  example  the  use  of  the  formula  [5990(11)],  we  shall  suppose  the  mean 
motion  to  be  «<  =  332''28"54',77,  log.  e  in  seconds  =  4,7041513,  or  e  =  50600' 
nearly.  Then,  for  a  first  operation,  we  shall  take  m,  =  320'',  from  which  we  find,  as 
below,  !(,-)-a;  =  324'' I6"'20'.  Taking  this  for  u, ,  in  a  second  operation,  we  finally 
obtain!/  =  524''16"' 29',5  ;  which  is  its  true  value,  as  will  appear  by  the  following 
calculations. 


[5990] 

(23) 
(24) 
(95) 


(20) 


FIRST    OPERATION       «,  =    320''. 

SECOND    OPER.\TION       M,  =   324"   iG™  20'. 

11,  =  326''                         log.sin.9,74756i7„ 
e                                      log.      4,7o4i5i3 

^=  3i 

u,  =  324''  i6"  20'         log.sin.9,7663644„          Jv  =    29 
e                                      log.       4,7o4i5i3 

e.sin.u,                            log.      4,45i7i3o„ 

At  =  i53 

e.sin.M,                              log.        4.47o5i57ii         ft  =  i47 

e.sin.u,  =  —  28295'  =  —  7"*  Siik  35'         /.<  - 
nt  =    332''  28"'  55' 

—  K  =  122 

c.sin.M,  =  —  29547', 16  =  —  8'' 1 2'»  27',i6  ^  —  ^=  118 
nt  =  332"  28"'  54«,77 

nt  +  e.sin.u,  =    324"  37'"  20'  =  jî 
u,  =    Ssô"*  00"'  oo« 

ni  -\-  e.sin.u,  =  324''  16"  27«,6  =  .4 
w,  •=  324''  ifi""  20' 

{nt  —  u,-\-  e.sin.u,)  =  —  i**  22"'  4o'  =  —  4960^ 
multiply  this  by 

± =-f- î^gives  —  ai^oo»  =  S     nearly 


(27) 


(nt  —  M, "4"  e.sin.u,)    = 
multiply  this  by 


+  7',e 


=t^— r=+3[||    gives    +i',g=B 


A  +  B  =u,+x 


32^(f  igm  20*. 


.« 


u  =  324''  16""  29»,5. 


Having  obtained  the  value  of  u,  we  may  compute  r,  v  from  [5985(9,11)]- 
but  as  the  method  of  making  this  calculation  is  sufficiently  obvious,  we  shall  not  "ive  an 
example. 

When  the  excentriciiy     e     is  very  nearly  equal  to  unity,  this  indirect  method  requires  the      [5991] 


use  of  tables  of  logarithms  to  more  than  seven  places  of  decimals.  For,  if  the  logarithms 
were  correct,  to  the  nearest  unit,  in  the  seventh  decimal  place,  there  might  be  an  error 
of  46%  in  computing  the  anomaly,  in  an  otbit,  where  1 — c=:  0,001  ;  and,  the  error 
would  exceed  this,  by  decreasing  1 — e.  In  this  case,  we  may  use  the  method  of  Simpson, 
given  by  La  Place  in  [694—698],  neglecting  all  the  powers  of  1 — e  =  a,  above  the 
first.  This  degree  of  accuracy  is  not,  however,  sufficient,  in  Halley's  comet,  where 
1 — c  =  0,03,  nearly  ;  for,  it  is  found  to  be  necessary  to  notice  the  terms  depending  on 
the  second  power  of  1 — n  ;  which  exceed  30%  when  the  anomaly  is  100'.  If  we  use 
the  same  notation  as  in  [694',  &ic.],  we  easily  perceive,  that  the  true  anomaly  v=^U-4-x 
in  the  ellipsis,  may  be  derived  froin  the  value  of    U,    corresponding  to  the  parabola,  by 

an  expression  of  the  following  form,  in  which  the  third  and  higher  powers  of     1 e  — g 

are  neglected  ; 

VOL.  III.  194 


(1) 

(2) 

(3) 

(4) 
(5) 

(6) 


774  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5991] 

V  =  V-i-S.{l—e)-i-B.i\  —  ey  =   U+S.a.  +  B.o.^  ; 


m 


(8) 


m 


S  being  the  value  of  the  function  [698],  corresponding  to  Simpson's  method,  and  B  the 
function  [5991(30)],  introduced  by  Bessel,  in  his  tables,  published  in  vol.  12,  p.  201, 
of  the  Monatliche  Correspondenz.  The  same  formula  may  be  applied,  ivithout  any 
modification,  to  a  hyperbolic  orbit,  which  approaches  very  near  to  a  parabolic  form,  by 
merely  noticing  the  sign  of    1 — e,     which  then  becomes  negative. 

(10)  In  the  computation  of    S    and    B,    we  may  put,  for  brevity,     tang.|t7=â,     or, 

(11)  cos.^jZ7  = 


1+tang.ail/  l+é^  ' 

Substituting  these,  in  the  expression  of    S     [698],  it  becomes. 

Method  of 
Simpson, 

byBeàséi.  To  obtain     B,     we  shall  develop  the  expression  [690],  according  to  the  powers  of  a, 

neglecting  terms  of  tlie  order     «■'  ;     hence  we  get  the  first  of  the  following  expressions  ; 

(13)     the  second    form  is  deduced  from  the  first,  by  multiplying  the  terms,  between  the  braces, 

by  the  external  factor     1  +ja--t-i|"-~  j     tlie   third  form  is  obtained,  by  arranging  the  terms 

according  to  the  powers  of    a  ; 

t  =  5^  .(l+k-+-|,a.2).tang.i«  .  ^       i  vj     a       g    ^       &    2  r 

/f.       ^  ^^  ^-    J       ^-       I     +(-^+.'50L2).tang.ni;+>^.tang.<-i«5 

=       ''Z^-  {  (l+|a+ia2).tang.ii)+(i-ia— icL2).tang.3ir— ia..tang5J»4->2.tang.7,^| 

ly— i.tang.^lt))  > 
i«+|5.tangJ|K)  5  ' 


(14) 


(15) 


D~.y^2     (  tang.|!;-[-3-tang^|y-|-"--(itang-i''  —  |.tang  ^i" — 1  tano- si 
//•''         I  -fa2.(i.tang.iu— ^.tang 


(16) 


If    a  =  0,     I'     changes   into      U,     and    the    expression    of    t     becomes   as  in   [691]. 
Putting   these  two  values  of    t     equal  to  each  other,  and  dividing  by  the  common  factor 

D^.\/2 

—^,     we  get, 

tang4C/-}-|.tang.^|l7  =  tang-lv+e-tang.^iy-f-a, .  |  i.tang.i« — i.tang.^|y — i.tang.'|w} 

+a2.  {â.tang.|w — ^.tang.^  •«-|-|'5.tang.''|»  J . 


(17)     If  we  put,  for  brevity,     x  =  So.~\-Ba?,     we  shall  have     v=U-\-x     [5991  (7)]  ;  and,  by 
neglecting   x^,    which  is  of  the  order     a^,     we  shall  get,  by  means  of  [29,  45]  Int., 

-)      tang.,«^tang.,(C^.)  =  ^SSl  =   ^  =  Hi-(l+^^)+l-^^-(l+^^)- 


SIMPSON'S  METHOD,  FOR  A  VERY  EXCENTRICAL  ORBIT.  776 


Re-substituting  tlie  value  of  x  [5991  (17)],  and  putting,  for  brevity,  l-{-ô^  =  ê^, 
we  get  the  following  expression  of  tang.it)  ;  from  which  we  easily  deduce  its  powers 
tang.'jt),     &:c.  ; 

tang.|u  =  ()+U....S'<),-fa2.0,.{iJ5+iS2j}  ;  (20) 

tang.3U'=  tî3+^a..S'()2t),+a.2.(),.{|Bd2-fiS2(^â,+é3)|  ;  (ai) 

tang.5it)=  ti*-|-|a.S()<(»,  +  8ic.  ;         tang.^iv  ==  f+hc.  ''^^ 

If  we  substitute  these  in  [5991  (IG)],  the  terjns  independent  of  a  will  mutually  destroy 
each  other;  also  those  depending  on  the  first  power  of  a:  and,  if  wc  notice,  in  the 
second  members  of  the  following  expressions,  only  the  terms  multiplied  by  a-,  we  shall 
have,  by  using  the  values  [5991  (20—22)],  and     Sê'^  =  (_|é+|é3+=()5)      [5991  (12)]  ;     («) 


[5991] 


<24) 


tang.Jj;+e.tang.3|v  =  a^J,.  Jii?.  (l+â9)+i5'2<3.(l+^.+ô2)  |  =  a,a.^  ■Bâ^+jS^âé.s} 

a.^.lang.ii'— i.tang.3>— i.tang.ni'5   =  o?.Sè^.\\—\è^—\è'^\  =  l<i?.S.\\—\è^—lè'^—t)^\;       ^s) 
a^^a-tang.!»— ^.tang.='i«+i\.tang.^Jf}  =  ^^.\gè—i,S'^i^-'].  t^^' 

The  sum  of  these  three   formulas  represents  the  terms  depending  on     a^,     in  the  second 
member  of  [5991  (16)]  ;   and,  as  this  sum  is  to  be  put  equal  to  nothing,  we  shall  get,  by     '--'''> 
dividing  by     \'^^~^,     the  first  of  tlie  following  expressions.     Substituting  in  this,  the  value 
of     5^,2     |-599^   (23)];     also     è^^  =l-\-2&^-\-èi  ;     and    then    reducing,    we  obtain   the 
second  value  of    B.1,*  ;     dividing  this  by     è*,     we  get  the  value  of    B  ; 

The  values  of  the  logarithms  of    S,     B,     in  seconds,  computed  by  Bessel,  by  means  of 
the  formulas  [5991  (12.30)],  with  their  first  and  second  differences,  are  given  in  Table  IV,     (^') 
of  this  collection. 

To  show,  by  an  example,  the  use  of  Table  IV,  we  have  here  inserted  the  computation 
of  the  true  anomaly  v,  in  an  orbit  which  does  not  differ  much  from  that  of  Halley's  comet  ; 
supposing  the  time  from  the  perihelion  to  be  60  days  ; 

e=z.  0,9675212;         log.(l—e)=  8,5115999  ;         log.peri.dist.  =9,7665598.  (3») 

With  these  data,  we  find, 


776 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5991]       -O 


(33) 


D 

Its  half 

t  =  6o  days 

log.  CO 

log. 
log. 

log- 
log. 

log- 
log, 
log. 
log. 

log. 

0,2334402 
0,1167201 
J,778i5i3 

Table  III.     U=Ç)T'  'O""  58',6 

2,i283ii6 

Table  IV.        S 

I  — c 

4,565o6 
8,5ii6o 

Simpson's  corv.    II93'',I 

3,07666 

Table  IV.        £ 
i  —  e 
I — e 

4,4333 
8,5ii6 
8,5ii6 

Bessel's  coir.          28',6 

1,4565 

From  Table  III,  for  the  parabola,  U^gj''  29"'  58»,6 

>impson's  correction,  Table  IV  -|-    ig""  53', i 

Bessel's  correclion,  Table  IV  -|-            28',5 

Sum  is  true  anom.  in  the  ellipsis  v  =  97''  5o'"  20s, 3 


(34) 


(35) 


In  a  hyperbolic  orbit,  in  which     e^  1,0324788,     we  shall  have, 

log(e— 1)  =  8,5115999  ; 

and,  if  we  suppose  t  =  60  days,  the  numerical  calculation  will  be  the  same  as  before; 
but,  1 — e  being  negative,  the  value  of  Simpson's  correction  will  be  negative  ;  and,  we 
shall  have,  in  this  hyperbolic  orbit. 


From  Table  III,  for  the  parabola 
Simpson's  correction 
Bessel's  correction 


U^  m-"  29"*  58',6 
—  19™  53',  1 
+  28',6 


True  anomaly  in  the  hyperbolic  orbit      v  =     97''   10"  34',1 

The  inverse  problem,  of  finding  the  time   t,  from  the  perihelion,  when   v   is  given,  is 

(36)  easily  solved,  if     1— e    be  so  small,  that  Bessel's  correction,  depending  on     B,     may  be 

(37)  neglected.  For,  in  this  case,  the  expression  [5991(7)]  becomes  U  =v—S.{\ — e)  ; 
and  S  may  be  obtained  from  Table  IV,  with  the  argument  v  instead  of  U.  Having 
found  U,  we  easily  deduce  from  it,  the  value  of  t,  by  means  of  Table  III.  Hence 
it  appears,  that  this  inverse  problem,  in  Simpson's  method,  merely  requires  a  change  in  the 
sign  of  the  quantity  S.  If  1 — e  should  be  so  great,  that  it  is  necessary  to  notice  the 
term  B,  it  will  be  necessary  to  repeat  the  operation,  by  an  indirect  method;  or,  more 
conveniently,  by  forming  a  table,  similar  to  that  used  in  finding  B,  by  which  the 
correction  of  Bessel  may  be  directly  obtained.  But,  in  this  case,  it  is  better  to  use  the 
method  of  Gauss,  which  is  not  restricted  to  the  first  and  second  powers  of  1 — e,  but 
includes  also  the  higher  powers  of  this  quantity. 


(38) 


(39) 


(40) 


[5992] 

(1) 


We    shall  now  proceed  to   the  investigation  of  this  method  of  Gauss,  for   the   direct 
solution  of  Kepler's  problem,  for  computing  the  true  anomaly    v,    from  the  time    t,    in 


GAUSSS  METHOD,  FOR  A  VERY  EXCENTRIC  ELLIPSIS. 


/  /7 


an  ellipsis  or  a  hyperbola,  luhich  approaches  nearly  to  a  parabolic  form  ;  and,  in  the 
demonstrations,  we  sliail  refer  to  any  line  of  [5992],  by  merely  putting  the  number  of  the 
line  in  a  parenthesis,  as  \\e  have  done  in  [5984  (2)],  omitting,  for  brevity,  the 
number  [5992].  In  this  solution  we  do  not,  as  in  the  preceding  method,  deduce  the 
anomaly  in  the  ellipsis,  from  that  in  a  parabola  having  the  same  perihelion  distance  D  ;  but 
we  obtain  it  from  a  parabola,  whose  perihelion  distance  is  increased  to 


[59U2J 


n  =  D 


5-3 


1  —  0,9 .  a 


i 


(41)  ; 


FFe  shaUJirst  treat  of  an  elliptical  orbit,  using  the  same  elements  as  before  ;  namely, 
a  the  semi-transverse  axis  ;  e  the  exccntricity  ;  2p=2a.(l — e^)  the  parameter  ;  D  the 
perihelion  distance  ;  nt  the  mean  anomaly  ;  u  the  excentrlc  anomaly  ;  v  the  true 
anomaly.  We  shall  also  use  the  following  abridged  symbols,  in  which  a,  a',  C,  differ 
from  those  used  by  Gauss  ;  this  change  is  made  in  order  to  conform  to  the  notation  generally 
used  in  this  work,  and  to  render  some  of  the  formulas  more  simple. 


a' 

= 

V/ 0,1-1-0,9.6 

J 

CL    = 

=   1-e  ; 

P 

== 

.5— 5e            a. 

1-H9e          2a' 

~2     J 

/'    ^ 

^  v/(5£) 

T 

=^ 

tang.-J«  = 

(S)' 

,tang. 

H^; 

f 

= 

1.5.(m  —  sin.u) 

j 

9u-(-sin.« 

Tt 

9u-|-sin.u 

\/m 


20^* 


+  M 


or, 


T  = 


A 


C-îA 


The  quantities     A,     B,      C,     may  be  expressed  in  series,  by  the  substitution  of 

sin.M  =  u — -i?<^4-yi-ôM* — &c.     [43]  Int.  ; 
which  gives, 

u—ûn.u  =  Lu^—-X^ti^J^--\-u'—hc.  ; 
9M-|-sin.î<  =  10i<— |?/^-|-yi-ô?<^ — &c. 
VOL.  III.  195 


(9) 


(3) 


B  being  a  quantity    which  exceeds  unity,  by  terms  of  the  fourth  order  in    n    (18).     By 
this  means,  the  interpolations  in  Table  V  become  very  easy,  on  account  of  the  smallness  of    (4) 
log.  B,     and      C — 1,     as  well  as  the  smallness  of  their  variations  ;  so  that  we  are  enabled 
to  notice  all  the  powers  of    a,     with  but  very  little  additional  labor.     The   same  remarks 
may  be  applied  to  the  use  of  Table  VI,  relative  to  a  hyperbolic  orbit. 


(5) 
(6) 

(') 

(8) 

(9) 

(10) 

(11) 

(12) 

(i:)) 

(14) 
(15) 

(16) 


778  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5992]      Substituting  these  in     A     (12),  it  becomes, 

A  =  i«2— -i^M^— ^^l^^M^— &c.  ; 

(17)  or, 

\/A  =  iu—^^^u^—j^\-y—kc.  ; 

and,  in  liice  manner,  we  get, 

(18)  B  =  l  +  _-^_-«^— &c.  ; 

so  that  A  is  of  the  stcond  order,  relative  to  u,  and  B  differs  from  unity,  by  a 
quantity  of  the  fourth  order  only.  We  may  obtain  the  value  of  A,  in  terms  of  T,  by 
the  following  process.  From  [48]  Int.,  putting  2:=^m,  we  get  u  (20),  and  from  [30'']  Int., 
we  have    sin.u    (20),  by  using     T     (II); 


2.tang.iM  2.T2  i 

sm.M  = ^    =       ^  ^  ^  2.1    .(1  —  i  +  i  — oic.)  ; 


M  =  2.(tang.*M— itang.siM+itang.siu— &:c.)  =  2T2.(1— jT+iT^— &tc.)  ; 

'■*"  2.tang.iM     _  2.T* 

l+tang.2iM  "~  1+T 

hence  we  get,  by  substitution, 

(21)         1.5.(M-sin.M)  =  30.tI{|T— IT2+&C.}  =  20.T*.  jT— fT^+fTS— '|TH&c.|  ; 

^22,  (9M+sin.M)  =  2TJ.  { V-¥T+'^T2-&c.  \  =  20.T*.  { i_f,T+,\T^— f^T^+kc.  j . 

Substituting  these  in     Jl     (12),  it  becomes, 

_  T— fT2+9T3— '^T^-l-i5T5— &c. 
(23)  ~"    1-  AT+|,T2— ^l-p+^T^^fcc. 

T"  4  "pS  _1- 2''T'3 1592'T"'1_1_236568'T'5 93097192 'T'6|Stp 

™,  -■-  5  ■*•        I    35  J-  SC25  ••     "TMÔIÎS-'-  197071875-^     "poiA.. 

Inverting  this  series,  we  get, 

A 
T 


(35)  m    &-"   I   TT¥-^  T^5?^-"     I    Î1I5S7  5-^     I    1UT1J51?5-^  T^**-^-? 


as  we  may  easily  prove,  by  substituting  in  it   the  value  of    A     (24),   and  reducing,  by 
which  means  we  shall  find,  that  the  terms  mutually  destroy  each  other. 

If  we  substitute  this  value  of    -     in      C     (14),  it  becomes, 

^^^  C  =  1  +Tf  r^-^+^  lî-^M-âlMf  t^^+t/t¥5VV^-45+S^c. 

Hence  it  appears,  <A«<      C     differs  from  unity  by  terms  of  the  secoiid  order   in     A,  or 

(^'^     of  the  fourth  order  in     u     (17).      The   quantities     Jl,     B,      C,     are    functions    of  T, 

(28)     which    have  been   computed   by  the  preceding  formulas,  and  inserted  in  Table  V.  By 

(99)     means  of  this  table  we  can  easily  find,  by  inspection,  the  values  of    A,     C,     log..B,  for 


GAUSS'S  METHOD,  FOR  A  VERY  EXCENTRIC  ELLIPSIS.  779 


(30) 


any  given  value  of  T,  or  the  contrary;  and,  as  the  quantities  C,  log.B,  vary  so 
slowly,  in  the  most  useful  part  of  the  table,  it  is  very  easy  to  take  out  the  corresponding 
numbers,  wliich  we  shall  hereafter  find  to  be  one  of  the  great  advantages  of  the  method 
of  Gauss.  After  this  digression  on  the  method  of  computing  Table  V,  we  shall  proceed  t^^) 
to  the  investigation  of  its  uses  in  the  direct  solution  of  Kcjpler^s  problem,  of  finding  r,  v 
from     t,     in  a  very  excentric  ellipsis. 

Substituting  the  value  of    nt     [5987  (12)],  in  [5985  (7)],  neglecting     m     on  account 

D  .  (^^' 

of  its    smallness,   and   then    putting     n= [5985  (C)],  we  get  (34).     From  this  we 

easily  deduce  (35),  since  by  multiplying  together  the  two  factors  of  (35),  and  reducing,  it 
becomes  identical  with  the  second  member  of  (34).     Now,  the  value  of    B     (13),  gives, 

9m  +  sin. M  =  20 A^.B  ;  03) 

substituting  this  in  (35),  in  the  factor  without  the  braces,  also  the  value  of    A     (12),  we 
get  (36);  whence  we  easily  deduce  the  expression  (37)  ; 

,'i  —  e\z 
k.t  .[  — =—  )  =  u  —  c.sm.w  (3<) 


[.'iQSa] 


,^      ,     .       .      (  1 — e    ,    l4-9c      u  —  sin.n  } 

(9w  +  sin.?0  .  < . } 

^        '  ^     ^     10     ^      10        9«+sin.u  3 

i    „     C  1  — e  I  +  9e      A   ) 

20A'.  B  .  {  +   — .  —  { 

^     10     ^       10        15  3 


(35) 


(36) 


C  il  ?    ) 

=  2B  .  ]  (1  — e).^-+ —  .  (l+9c).^-  [  ;  (37) 

in  which  we  must  substitute  the  value  of  log.t  =  log-y/f^  =  8,2355814...  [5987  (8,16)]. 
If  we  now  suppose, 

A^'=  r\      ~lj   ■  tang.JM>  ,      or      A  =  ^.tang.^w     (10),  (38) 

and  substitute  it  in  the  preceding  expression,  every  term  will   have    the    factor     (1 — e)^  ; 
then  dividing  by  this  quantity,  we  get, 

t  . =  2iî .    .  Uane.Àw  4-  J.tang.^J^wK  _ 

Multiplying  this  by, 


7   •  Bk.^^-      ^  '' 


Bk^  \      5      y  ■  Bk.^2      '-'  '  <''' 

we  finally  obtain. 


780  APPENDIX,  BY  THE  TRANSLATOR  ; 

i'^l^  -^.^  =  f.{tans.à-+^-.tang.3J.|. 

(40)  J5J5^  k 

Now,  from  the  construction  of  Table  III  [5987  (22)],  it  appears,  that  the  tabular  number, 
corresponding  to  the  anomaly  w,  represents  the  logarithm  of  the  second  member  of  this 
expression  ;  so  that,  if  we  put. 


0,l+0,9.c/  VI— 0,9.a/ 

and  then  substitute  D^  and  a'  (9),  in  (40),  we  shall  get,  by  making  successive 
reductions  in  its  first  member,  the  following  expressions  ; 

a'             (0,l+0,9.e)H     t  ,       .  ,    ,       •   -n  ,,    ,„  ,■  ,      '       , 

/4g\  f —^^ ! — — :^  number  of  Uie  log.,  Ill  lablc  in,  corresponding  to  Ine  anomaly  t£j   ; 

so  that,  if  B,  and,  therefore,  J),,  be  known,  we  can  determine  the  relation  of  w  and  t, 
by  means  of  Table  III.  Hence  it  appears,  that,  in  the  direct  solution  of  Kepler'' s  problem, 
in  a  very  excentrical  orbit  ;  where  t  is  given,  to  find  r,  v;  vie  can  obtain  iv  from  t, 
by  means  of  (42)  ;  and  then,  from  w,  we  get  A,  by  means  of  formula  (38);   namely, 


(43) 


A=  (3.tang.2i«'=     'çr^  ■  tang.^iif  =  —.tang.^Ji 


l+9.e 

Now,     B     differs  so   little   from  unity  (18),  that  we  may,  in  a  first   rough  calculation, 
(«)    suppose     J9=l  ;     and,  upon  this  supposition,  we  can  compute  the  approximate  values 

(45)  of  w  and  A  (42,43).  With  this  value  of  A,  we  find,  from  Table  V,  the 
expression  of  log.B  ;  and,  by  repeating  the  calculation,  with  this  value,  we  get  the 
corrected  expressions  of  w,  A.  In  general,  this  second  operation  will  be  sufficiently 
accurate,  except     u     be  very  great.     It  frequently  happens,  when   several  observations 

(46)  are  computed,  for  successive  days,  that  the  value  of  log.i?  is  very  nearly  known  at  the 
commencement  of  the  operation  ;  in  this  case,  we  must  use  this  approximate  value  of  B, 
in  the  first  operation  ;  and,  it  will  generally  happen,  that  one  operation,  in  such  cases,  will 
be  sufficient  to  obtain  the  correct  value  of    w. 


(47) 


(48) 


(49) 


(50) 


Having  obtained  the  value   of    A,     we  find,  from  Table  V,  the   corresponding  value 
of     C  ;     from  which  we  get, 

T  =  tang.'éM  =     c^TJ       (H.  14), 

vifith  more  accuracy  and  less  labor,  than  it  could  be  directly  obtained  from  Table  V. 
Substituting  this  value  of  tang.^gW,  in  (1 1),  we  get  the  first  expression  of  tang.|j)  (51). 
Substituting  in  this,  the  second  value  of  A  (43),  rejecting  the  factor  (1 — e)^,  which 
occurs  in  the  numerator  and  denominator,  then  introducing  the  first  value  of  y  (10), 
we  get  the  second  expression  (51); 


GAUSS'S  METHOD,  FOR  A  VERY  EXCENTRIC  ELLIPSIS.  781 


Having  found     u,     v,     we  may  compute     r     from  either  of  the  formulas  [5985  (9,10)], 
or  from  the  following  ; 

_   J0.cos.2|«    _  D  _        {C—^A).D 

cos.^it'     ~    (l+T).cos.2^   ~   {C+iAycosJiV 


[5'J92J 

(SI) 


(52) 


The   first  of  these  expressions  is  easily  deduced  from    the   last  formula  [5985  (13)],  by 
substituting     a.(l — e)^D     [5985(6)],  then  squaring   and   reducing.     The  second  is     (53) 
obtained  from  the  first,  by  putting, 

and  the  third  is  deduced  from  tlie  second,  by  the  substitution  of  tiie  value  of  T  (14). 

The  inverse  •problem  of  finding  the  time  t,from  the  true  anomaly  v,  is  also  solved  by  means 
of  Table  V.     In  this  case,  we  must  first  compute    T,    from    i;,    by  the  formula  (11)  ; 


(55) 


1 e 

T  =   .tang.^iv.  (56) 

1+e  "    ^ 

With  the    argument     T,     we  must  enter   Table  V,  and  take  out  the  number     A,     and 
the     log.-B;     or,  what  is    more  convenient,  and,   at  the  same  time,   more   accurate,    the 

(57) 

number     C,     and   the     log.i?  ;     then  compute     A,     by  the  formula  (14), 

CT 

A  =  q:^;  (58) 

lastly,  we  must  find     t,     by  means  of  the  formula  (37).      This  expression,  being  divided 
by  the  factor  of    t,     gives, 

t  =  l.D^.AKB.(\-e)-^.  I  l+,V^.(l+9e).(l-e)-^  |  ; 
and,  if  we  put, 

t,  =  l.DlAKB.(l-e)-^;       t._  =  t,.,\.A.{l+9eUl-e)-^   ; 
we  shall  have, 


(59) 


(60) 


t  =  t,  +  t,   ;  (61) 

and,  it  is  under  this  form,  that  the  value  of  t  is  computed  in  the  introduction  to  Table  V, 
observing,  that  we  have, 

log.^- =  2,0654486     [5987(8)],     and     log.  J,  =  8,8239087 .  ^^^ 

VOL.  III.  196 


782  APPENDIX,  BY  THE  TRANSLATOR; 

[5993]  yy-g  i^jgy  ^]g^j  compute     t,     from     v.     by  means   of  Table  III  ;    but,  this   table  does 

(^3)     not  facilitate  the  operation,  as  it  does  when  finding     r     from     t.     In  using  Table  III,  for 
this  purpose,  it  will  not  be  necessary  to  compute    A.     For,  we  bave,  in  (43,56), 

,.„,.i.,.=^..(S:)s      ,»,....  =  (sy.T. 

Dividing  the  first  of  these  expressions  by  the  second,  we  get  the  first  of  the  equations  {66); 
substituting  j~  (10),  we  get  the  second  expression  {66);  and,  by  using  A  (58), 
we  get  the  last  of  the  formulas  {66)  ;  from  which  we  easily  obtain  the  first  value  of 
tang.|w  (67).  The  second  formula  (67)  is  derived  from  the  first,  by  the  substitution 
of  the  second  value  of    y     (10). 

tang.iw    _    fA\h   p-l-9A4_  (   ^\- _  .     /        C  . 

e)  -  VTvV  V     7^\+%^)    ' 


(65) 


(66) 


tanç.Ji)  \Ty  A5+5e 


or, 


(67)  l'l"g-2 


tang.ittJ  = 


(68) 


Havin°-   found,  in   Table    III,    tlie  time  corresponding   to  this  anomaly     iv,     we    must 

3 

multiply    it    by       — —  ,     to  obtain  the  time     t     from  the  perihelion  ;  as  is  evident  from 
the  first  of  the  formulas  (42). 


Table  V  is  given  for  every  thousandth  part  of  a  unit,  from  A  =  0,000  to 
t09)  yl  =  0,300.  It  was  thought  to  be  unnecessary  to  extend  it  any  farther  ;  because 
A  =  0,3  corresponds  to  T=  0,392.374  =  tang-^Jw  (1 1),  or  w  =  64"  7"  ;  and, 
with  such  large  values  of  ti,  the  indirect  method  of  solution  is  the  shortest,  as  we  have 
already  observed.  This  table  is  arranged  so  as  to  make  it  most  convenient  for  use  in 
finding  B,  C,  with  the  argument  A,  in  the  first  problem,  where  t  is  given  to 
find  V,  which  is  by  far  the  most  frequently  required.  In  this  case,  the  number  T  is 
not  used.  In  the  second  problem,  the  argument  T  is  used  to  find  B  and  C,  which 
are  small  and  easily  computed  ;  and  then  A  is  found  directly,  by  means  of  the 
formula  (58). 

We  shall  apply  this  method  to  the  compulation  of  the  same  example,  as  in  [5991  (33)]. 

EXAMPLE     1. 

Given,  e  =  0,9675212,  t  =  m'^y\ 

be.  perih.  dist.  D  =  9,7665598,  a  =  1  —  e  =  0,0324788. 

(73)  '^     ' 

(,'2  __  0,1  -f  0,9. f  =  0,9707691  ;     to  find     t,     v,     in  an  elliptical  orbit. 


(70) 


(71) 


(72) 


GAUSS'S  METHOD,  FOR  A  VERY  EXCENTRIC  ELLIPSIS. 


FIRST    OPERATION    TO    FIND       I). 

0,'2  log.  9,9871159 


a' 
D 

t=  60 

log. 

log.   CO. 

Its  half 
log. 

9,9935579 
2334402 
1 167201 

1,7781 5i3 

U  =  gô^SS"  Table  III. 

log.i' 

2,1218695 

a 

è 

log. 

log.  CO. 
log. 

8,5 1 1 5999 

128841 

9,^989700 

/3 
èC=  48''  29" 

log. 

taog. 

same 

8,2234540 

o,o52g4 

o,o52g4 

Approx.  A  =  0,02 1 347 

log. 

8,32933 

TO    FIND    THE    RADIUS        /". 

C4-o,2.jî  =  i,oo42gi2    log.  CO.  g,g98i4o3 

C — o,8.^î  =  0,9829401    log.  9,9925270 

D         log.  g,76655g8 

4»   =  48'' 55'»  io',47                       sec  0,1823567 

same  0,1823567 


log. 


o,i2ig4o5 


SECOND    OPERATION    TO    FIND       V. 


783 


[5992] 


(74) 


— BLox  34,  found  by  the  first  operation      2,1218661. 
Hence     w  =  go"*  58™  2i«,6,     by  means  of  Table  III. 


(75) 


Jio  =  48''  29*"  ios,8 


same  8,223454o 

tang.  0,0529828 

same  0,0529828 


A  =  o,02i35ii         log.  8,3394196 


C  =  1,0000210 
o,8.-î  =  0,0170809 

C  —  0,8.^  =  0,9829401  log.  CO.  0,0074730 

1 -|-e  =  1,9675212  log.  0,3939194 

I  e  =  (j|_  log.  CO.  1 ,4884001 

tang.Sà"  'og-  2^o,II92I2l 

il)  =  48''  55™  io',47  tang.  0,0596060 


»  =  97''  So"  2o',94     (51). 


(76; 


(77) 


This  value  of    v     differs     0',64     from  that  found  in  [5991  (33)],  by  noticing  only  the 
corrections  of  Simpson  and  Basse). 

EXAMPLE     II. 

In  the  inverse  problem,  with  the  same  elements,  we  have  given, 

the  anomaly  t>  =:  97"  50""  20',94  , 

to  find     t,     in  the  following  manner,  by  means  of  the  formula  (61). 


(78) 


I — 6  =  0,0324788  log.        8,5115999 

I  ■\-  e  =  1,9675212  log.  CO.  9,7060806 

4w  =  48''  SS""  io»,47  lang.       0,0596060 

same       0,0596060 

T  =  0,02173163         log.         8,3368925 
Hence     C  =  1,0000210  log.  91 

I  -|-o,8.T  =  1,0173773  lug.  CO.  9,9925180 

A  =  o,02i35ii  log.        8,3294196 

Corresponding  log.  B  in  Table  V  o,ooooo34 


Constant  log.  3,o654486 

|.  log.  D  9,6498397 

è  log.  A  9,1647098      (79) 

log.  B  34 

è  log.  (i  — e)  arith.  co.  0,7442000 


.  ,  days 

<    =  42        ,09 


log.  1,6243015 

('onstant  8,8239087 

A  log.  8,3394196 

.    I  +  9e  =9,707691    log.  0,9871159       (SO) 

(i  —  e)  log.  CO.  1,4884001 


.7''"",9o8 


log.     i,353o458 


t  =  60 


days 


=  '.  +  '■ 


784 


APPENDIX,  BY  THE  TRANSLATOR: 


[5992]  We  shall  now  compute  the  same  example   by  means   of  Table   III  ;  by  which  means  it 

^^'^    will  evidently  appear,  that  the  preceding  form  is  the  shortest  and  most  simple. 


(82) 


(83) 


(84) 


è  »  =  48<*  55""  4o',47 


I  —  e 


log- 
log.  CO, 
tang, 
same 


T  =3  0,02172163 
C  =  1,0000210 
i-|-o,8.T  =  1,0173773 

A  =  o,02i35ii 

Corresponding    log.  B,    Table  V 


8,5115999 
9,7060806 
0,0596060 
0,0596060 

8,3368925 
9' 


log- 
log, 
log.  CO.   9,9925180 

log.         8,3294196 

0,0000034 


a'2  =  0,9707691 


log. 
2  log- 


sum 

half 
lana. 


è»  =  48''55">  io',47 
hw  =  48''29"'io»,8 

to  =  96*58"  3i',6  Table  III  log.  (' 

Table  V  log.  B 

D  log. 

D^  log. 

d'  log.  CO, 


9,9871159 

9,7060806 
o,3oio3oo 


91 

9,9926180 

!)9,9867536 

9,9933768 
0,05960(10 


tang.         0,0529828 
2,1218662 

M 

9,7665598 

9,8832799 

64421 


(  =  60 


dnys 


log. 


I,778i5i4 


[5993] 


We  shall  now  proceed  to  the  explanation  of  the  method  of  computation  in  a  hyperbolic 
orbit  ;  in  which  the  elements  are  ;  «  the  semi-transverse  axis  ;  e  the  excentricity  ; 
2p  ==ia.(e^ — 1)  the  parameter;  D  the  perihelion  distance.  We  shall  also  use  the 
following  abridged  symbols,  which  are  similar  to  those  in  [5992  (9 — 14)],  corresponding 
to  an  elliptical  orbit.  In  the  demonstrations  in  this  article,  we  shall  refer  to  any  line  of 
(5)     [5993],  by  merely  putting  the  number  of  the  line  in  a  parenthesis,  as  in  [5984  (2),&c.]. 


(1) 

(2) 

(3) 
(4) 


(6) 


C) 


(8) 


(9) 


(10) 


(11) 


(12) 


c-?;^ . 


"+1/ 


B  = 


V/ 0,1+0,9.6  ; 

5e-5  _   e-1  _  y/5{e-\-})\   ^  /{'±}\ 

l+'Je  ~~   20.'=   '  ^  \X    U+ye/  y/    V2-^'V 

e 1 

tang.^Jis  =  ^qT^-tang.^èt'  = 

tang.(45''+|^)  ; 

î'o  •(«  —  -) +is-log.M 
,v(m— ^)+iyog.w 


2^  A 


;  — M 


T  = 


A 


C+tA 


GAUSS'S  METHOD,  FOR  A  HYPERBOLIC  ORBIT.  785 

We  may  observe,  that  the  expression  of    u     (9)     is    the  same  as  in   [5989(12)]  ;  and       [5993] 
the  last  expression  of    tang-.i«',     or     T     (8),  is  deduced  from    it,  in  the   same  manner 
as  in  [5989(13)].    This  last  value  of    T     (8)  gives, 

1+Ti 


i     ' 


1— T* 


hence,  ''^' 


1  (1+T*)        (1— Tn  4T1 

"-  u  =  I^tT  -  -Ï+TT  =   ^z-]^=4T^l+T+T^+T'+&c.)  ;  .a, 

and,  from  [58]  Int.,  we  have, 

log.«=log.(i±5)  =  log.(l+T*)-log.(l-T')  (u, 

=  (t*+|T^+^T^  +  &c.)— (— Ti+|T^_>T^+&ic.) 
=  2Ti.(I+JT+iT2-KT3+&c.);         hence,  ^,^^ 

§-[i  •(«  -  J)  -log.«  I  =3Ti.{iT+|T2+?T3+&ic}=2T^.{T+|T2+|T='+^'T^+&c};     ^^^^ 

^^  •("  - 1)  +«-log-«=2T^^  (i]i+,VT+,'5T='+,'oT3+&ic)+,|(l+,^T+iT=^+|T3+&c)  j     ^^^^ 
=2Ti.  f  l+BT+l.T^+I^T^+^c.  S . 

(IB) 

Substituting  the  expression  (16, 18)  in  the  value  of    ^     (10).  and  rejecting     2T*     from 
the  numerator  and  denominator,  we  get, 

T+fT^|-T3  +  ^°T^-}-&C.  -p   I  ^rpa   ,   24'r3  I   .59--T4-l_  &•,. 

^  I+6JT+/3T3+I5T3+&C.  •^  +  =■■1     +3li    i-5S55l    +ûiC.  ^^^^ 

this  may  be  derived  from  the  expressions  [5992(23, 24)],  by  changing  the  signs  of  ^4,  T; 
and,  if  we  make  these  changes  in  [5992  (25,26)],  we  shall  get,  for  an  hyperbolic  orbit, 

/J 

Extracting  the  square  root  of  the  expression  of    A     (19),  we  get, 

\/A  =  Ti.  1 1+  ft  T  +  r*r%  T^+  &c.}  ;  ^^ 

substituting  this,  and  (18),  in     B     (H),  we  get. 


(94, 


VOL.    HI.  197 


786  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5993]  Now,  if  we  consider  ■us  as  a  small  quantity  of  the  first  order,  we  shall  have  T  (8) 
^^"  of  the  second  order,  and  A  (19)  of  the  second  order.  Hence  C,  B  (22,24)  differ 
(26)    from  imity,  by  quantities  of  the  fourth  order.     These  values  of    A,     B,     C,     T     have 

relations  to  eacli  other,  which  are  very  similar  to  those  in  the  ellipsis  [5992  (15 — 31)]. 

These  quantities,  for  the  hyperbola,  are  given  in  Table  VI  ;  which  is  arranged  in  the  same 

way  as  Table  V,  for  the  ellipsis  ;  and  is  used  in  the  same  manner  as  in  [5992  (29),  &ic.]. 
(38)    The  numbers  in  Table  VI  are  computed  for  values  of    A,     from  0  to  0,300  ;    which  is 

sufficiently  extensive  for  practical  purposes. 

We  have  in  [5983  (6)], 

Jc 

(29)  — .  i  =  e  .  tan^.  zi  —  log.  tang.(45''-J- J-ra). 

a^ 
Substituting  in  this  the  values  of    tang.w,     tang.(45''-j- ^ w)     [5988(15,13)]; 

D 

(30)  also,         a  = [5988  (4)], 

we  get  (34)  ;  and,  as  we  have  identically, 

(31)  |e=^V•(e-l)  +  ^(TV  +  T^^e)  ;  -1  =A-(«-l)-(TV  +  T\e); 

as  is  easily  proved  by  reduction  ;  we  may  substitute  these  factors  of    %i —  -,    andoflog.w, 

in  the  second  member  of  (34),  and  it  will  become  as  in  (35).     This   may  be   still   farther 
reduced,  by  observing,  that  the  product  of  the  expression  (11),  by     2A^,     gives, 

(32)  2-V  •  ("—7,)  +  T^-log-«  =  2J5.^*; 

substituting  this,  in  the  denominator  of  the  value  of    A    (10),  and  then  multiplying  it  by 


(33) 


X  2B.^A ,     we  get, 

|i-("-^)  -log.M|=|B.^ 


Using  these  two  last  expressions,  we  find,  that  the  function  (35),  is  reduced  to  the  form 
(36),  or  the  equivalent  expression  (37)  ;  which  is  very  similar  to  that  corresponding  to 
the  eUlpsisin  [5992(37)]. 


e— IM  /  1 


(34)     A;.(  -^j  .<  =  4e.  («  —  -)— log.M 


(35) 


(36) 


(37) 


=  (e-l).2B.^*+(J^+Ae).f.B.^- 
=  2B.  \  [e-[).A^+^\.{\+9e).A^  |  . 


\.[  u ) — los;.t«; 

u. 


GAUSS'S  METHOD,  FOR  A  HYPERBOLIC   ORBIT.  787 

If  we  suppose,  [WDS] 

^  =  (-[     ~lj  •  tang.î'jM)  =  ^ . tang.2^i«     (7),  (M) 

3 

and  then  substitute  this  first  value  of  A  in  (37),  we  shall  get,  by  dividing  by     (e  —  1)^, 

—^.t  =  2B.  (-q^  V-  {tang.4t«  +  J.tang.'iwj .  (=9) 

Multiplying  this  by. 


/l+9e\é  1 


we  finally  obtain, 


-^   .<  =  ^-.{tang.^îo+J.tang.^àw;}.  Ho) 


(•II) 


This  is  of  exactly  the  same  form  as  [5992  (40)],  in  an  ellipsis  ;  and,  if  we  put,  as  in 
[5992(41)], 

we  shall  get,  as  in  [5992  (42)], 

a'             (0,l+0,9.e)  t 
.t  = .  t  ^=  — =■  number  of  the  log.,  in  Table  III,  corresponding  to  the  anomaly  w   ;  (42) 

Boi  BOi  D,i 

so  that,  if  B  be  known,  we  can  determine  the  value  of  iv,  by  means  of  Table  III. 
Therefore,  in  the  direct  solution  of  Kepler's  problem,  in  a  hyperbolic  orbit;  where  t  is 
given,  to  find  r  and  v  ;  we  can  find  w  from  /,  by  means  of  (42)  ;  and  then,  from  w, 
we  get  A,  by  the  following  expression,  which  is  th€  same  as  in  (38); 


A=  f3.tang.^Jî«=    '      ^^  .  tang.'' J w  =  ^.tang.^Jw. 

Now,  B  differs  so  Utile  from  unity  (24).  that  we  may,  at  first,  suppose  B^l; 
and,  with  this  assumed  value,  we  can  find  the  approximate  values  of  w,  A  (42,4-3). 
With  this  value  of  A,  we  obtain,  from  Table  VI,  the  expression  of  log.J9;  and, 
by  repeating  the  calculation,  with  this  value,  we  get  the  corrected  expressions  of 
w,  A.  In  general,  this  second  operation  will  be  sufficiently  accurate,  as  we  have  (46) 
observed  in  the  similar  calculation  for  an  elliptical  orbit  [5992  (46)]. 

Having  obtained  the  value   of    A,     we  find,  from  Table  VI,  the   corresponding  value 
of     C  ;     from  which  we  get, 


(43) 


(44) 


(45) 


788  APPENDIX,  BY  THE  TRANSLATOR  j 

[5993]  ^ 

(«)  T  =  tang.^J^  =     Qj^.j^       (8,  12), 

with  greater  accuracy  and  with  less  labor,  than  it  could  be  directly  obtained  from  Table  VI. 
Substituting  this  value  of  tang-^l^r,  in  (8),  we  get  the  first  expression  of  tang.|«  (49). 
Substituting  in  this,  the  second  value  of  A  (43),  rejecting  the  factor  (e — 1)=,  which 
occurs  in  the  numerator  and  denominator,  then  introducing  the  first  value  of  y  (7), 
we  get  the  second  expression  (49)  ; 


(48) 


(49) 


tang.è.  =  ^î±}  .  \/ 


A        ^    y.tang.^t<; 
C+M         \/C+fA  ' 


Having  found     «,     v,     we  may  compute     r,    from  either  of  the  formulas  [5988(11,12)], 
or  from  the  following  expressions  ;  which  are  similar  to  those  in  an  ellipsis  [5992  (52)]  ; 

D  (C+^A).D 

(50)  r   =  _^       \    ^  t    J 


(1— T).cos.2^y  (C—iA). cos.^iv 

The   first  of  these  formulas  is  deduced  fiom  the  last   expression  in  [5988  (20)],   which 
gives,  by  squaring   and  reducing, 

_  (m+1  f  o.(g— 1) 
(51)  4u     ■  C0S.2  4  i;  ' 

Now,  from  the  value  of    T     (8),  we  have, 

^-^  =  '-(^ù'=(^^'     ^'^°     «.(e-l)  =  l>     (30). 

Substituting  these  in  the  preceding  value  of   r,  it  becomes  like  the  first  expression  (50)  ; 
and  the  second  expression  is  deduced  from  the  first,  by  using  the  second  value  of  T  (47). 


(53) 


Theinverse  problem  of  finding  the  time  t,from  the  true  anomaly  v,  may  be  solved  by  means 
of  Table  VI.     To  effect  this,  we  must  first  compute     T,    from    v,    by  the  formula  (8)  ; 


e 1 

(54)  T  =   —  .  tang.2|i; . 

With  the  argument  T,  we  must  enter  Table  VI,  and  take  out  the  number  A,  and 
the  log.i?;  or,  what  is  more  convenient,  and,  at  the  same  time,  more  accurate,  the 
number  C,  and  the  log.S  ;  then  compute  A,  by  the  following  formula;  which  is 
easily  deduced  from  (47)  ; 

CT 


(55) 


A  = 


(56) 


1— tT' 


lastly,  we  must  find     t,     by  the  formula  (37).      This  expression,   being  divided  by   the 
factor  of    t,     gives. 


GAUSS'S  METHOD,  FOR  A  HYPERBOLIC  ORBIT.  789 

[5993] 

observing,  that  we  have,  as  in  [5992  (62)], 

log.^=  2,0654486  ;         logji  =  8,8239087.  (s?) 

Ihen,  if  we  put, 

t,^\.D^.A^.B.{e—\)-^;       t,  =  t,.i,.A.{l+9e).{c—\)-^  ;  (58) 

we  shall    have  the  following  expression  of    /,     which  is  exactly  similar  to  that  for  an     (59) 
ellipsis  [5992(61)]; 

t  =  t^  +  1„  ;  (60)  . 

and,  it  is  under  this  form,  that  the  value  of  t  is  computed  in  the  introduction  to  Table  VI. 

If  we  wish  to  use  Table  III,  which  does  not,  however,  facilitate  the  operation,  it  will 
not  be  necessary  to  compute    A.     Then,  we  shall  have, 

tang.  >  =  AK  Q-g)*     (38)  ;  tang.J.  =  ^^.(^J  (54).  (6» 

If  we  divide  the  first  of  these  expressions   by  the   second,   then  substitute  the  values   of 
y  (7),  also  that  of    A    (56),  we  shall  get,  by  successive  reductions, 

tang-l^.    _    (A\h    /l+9eY_  (  A\^=  t    /        ^  •  (ca) 

tang.J.  Vt;  •  V5e+5;         VTvV         V    7^.(1— |T)  ' 

tang4^«  =  \/ :,,:^^'  '^^S-hv  =  \/ ^^^^~::^y  tang-è^^- 
Having  computed  the  value  of    w,     from  (63),  we  may  then  find,  in   Table  III,  the  time 

3 

corresponding   to  the  anomaly     «•.     We   must  multiply  this  time  by      — ;—       (42),      to     (64) 

obtain  the  time     t     from  the  perihelion.     The  remarks  made  in  [5992  (69 — 72)],  relative 
to  the  construction  of  Table  V,  will  apply,  with  the  proper  modifications,  to  Table  VI. 

To  illustrate  this  method  of  computation  we  shall  give  the  following  examples. 

EXAMPLE     I. 
Given,     e  =  1,2500000  ;     log. perih.dist.  0,0200000  ;     r  =  GO""^)",       to  find     t,     v.     (^s) 

VOL.  III.  198 


790 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5993] 


APPROXIMATE    OPERATION    TO    FIND       V. 


a'2 


(66) 


(67) 


(68) 


=  0,1  +o,9.e=  1,225 

log. 
log- 

0,088 1 36 1 

a' 

0,0440680 

D 

log.  CO. 

g,g8ooooo 

its  half 

g,ggooooo 

t  =  6o'î''y' 

log. 

I,778i5i3 

Approx. 

log.  t' 

1,7922793 

;  Cr=66''44'",  nearly,  in 

Table  III 

e  —  I  =  o,25 

log. 

g,3g794oo 

a'a 

log.  CO. 

9,9118639 

Constant 

log. 

9,6989700 

Sum  given  /2 

log. 

9,0087739 

iU==33''  22m 

tang. 

9,8 1 85849 

same 

9,8i85849 

Approx.  JÎ  =  0,044253 

log. 

8,6459437 

iponding  log.  j5  =  o,ooooi45  Table  VI. 

TO    FIND    THE    RADIUS    r. 

C —  o,2.jî  =  o,ggi236o 

log.  CO. 

o,oo3823o 

C  -1-  o,8..4  =  1 ,035496g 

log. 

o,oi5i488 

D 

log. 

0,0200000 

è»  =.  3i''48™3i%3 

sec. 

0,0706768 

same 

0,0706768 

log. 


o,i8o3254 


CORRECTED    OPERATION    TO    FIND    V. 


Subtract  log.B  =  o,ooooi45  gives correc.  log.*'  i ,7922048 
Hence  U  or  iv  =  6&^  AA™  iG^g  in  Table  III. 


same 

4  tc  =  33"^  22™  o8=,4    tang, 
same 

log. 


Constant  A  =  0,044260g 

0,8.^  =  0,0354087 
C  =  1 ,0000882 


9,0087739 
9,8186233 
9,8186233 

8,646o2o5 


C-j-o,8..^  =  1,0354969 
e-[~  '  =  2,25 
e  —  I  =  0,25 

Sum  is  2  log.  tang  \  v 

à  u  =  3i<i4Sm3t«,3 

o  =  63''  37""  02«,6 


log.  CO.  9,9848512 
log.  0,3521825 
log.  CO.  0,6020600 

9,585ii42 
tang.   9,7925571 


(69) 


EXAMPLE    II. 
In  the  inverse  problem,  with  the  same  elements,  we  have  given, 

e  =  1,2500000  ;     log.  perlh.  dist. 0,0200000  ;     and     y  =:=  03"  37™  02^G 
to  find     t,     in  the  following  manner,  by  means  of  formula  (60). 


e — I  =0,25  log.        9,3979400 

e+  I  =  2,25  log.  CO.  9,6478175 

èî)  =  3i<'48"'3i«,3    tang.      9,7925572 

same      9,7925572 


(70) 


T  =  0,0427437  log.  8,5308719 
Hence  C  =  i  ,0000882  Tab.  VI  log.  383 
I  —  o,8.T  =  o,9658o5o    log.  co.  o,oi5iio6 

A  =  0,0442609    log.    8,6460208 


Constant  log. 

2,0654486 

J  log.  D 

o,o3ooooo 

à  log.  A 

9,323oio4 

log.  B 

i45 

4  log.  (e  —  i)  arith.  co. 

3oro3oo 

^=52''^^=,42I                                           log. 

i,7ig5o35 

Constant 

8,8239087 

A  log. 

8,646o2ù8 

.     I  -j-ÇÊ^  12,25             log. 

i,oS8i36i 

e  —  1     log.  CO. 

G020600 

'j=     7'^''^'.579                                  log. 

0,8796291 

60' 


days 


=  t 


t  . 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


791 


We  shall  now  compute  the  same  example  by  means  of  Table  III;  by  which  means  it 
will  appear,  that  the  preceding  method  is  the  most  simple. 


C  I    ^   0. 2^)00000 

e  -j-  I  =  2,25ooooo 
et)  =  3i''48"'3i»,3 

T  =  0,0427437 

■  0,8. T  =  0,9608050 

C  =  1,0000882 

.4  =  0,0442609 


log.  9,3979400 

log.  CO.  9,64781-5 

tang.  9,7925572 

same  9,7925572 


log.  8,630871g 

log.  CO.   o,oi5iio6 
383 


log. 
log. 


Corresponding  log.  B,   Table  VI,  is 


8,6460208 
0,0000145 


a'2  =  1,225 


log. 
2  log. 


o,o88i36i 
9,6478175 
o,3oio3oo 


O,oi5iio6 
383 


sum  2^o,o52i325 

half  0,0260662 

J»  =  3i''48"'3i',3                   tang.  9,7925572 

•iio  =  33'' 22">  o8»,4                   tang.  9,8186234 

to  =  66"* 44"  i6%8  Table  III  log.  t'  1,7922044 

Table  VI  log.  B  i45 

■D     log.  0,0200000 

i)*    log.  0,0100000 

a'    log.  CO.    9,9559320 

i=  60    ^'  neai-ly.     log.  1,7781509 


ON  THE  METHOD  OF  COMPUTING  THE  ORBIT  OF  A  COJIET. 

A  shon  time  before  the  publication  of  the  first  volume  of  the  Mécanique  Céleste, 
containing  La  Place's  method  of  computing  tlie  orbit  of  a  comet  [754 — S49],  Dr.  Olbers 
gave  a  much  shorter  process  for  solving  the  same  problem,  in  a  work  published  at  Gotha, 
in  1797,  entitled  Abhandlu.ng  ilber  die  leichleste  und  hequemste  Méthode  die  Balm  eines 
Cometen  aus  einigen  Beobachtungen  zu  bcrechncn  ;  and  as  this  method  is  but  little 
known  in  our  country,  we  shall  here  give  a  full  explanation  of  it,  and  shall  simplify  in  some 
respects,  the  calculation  by  means  of  Tables  I,  II,  of  this  collection  ;  which  have  been 
computed  and  examined  with  particular  care,  in  order  to  render  them  correct,  to  the  nearest 
unit,  in  the  last  decimal  place.  We  have  used  Table  II,  in  an  abridged  form,  for  several 
years,  and  have  found  it  convenient  and  sufficiently  accurate,  as  it  regards  the  number  of 
decimal  places.  We  shall  first  explain  the  method  of  Dr.  Olbers,  by  the  geometrical 
process,  which  he  used,  and  shall  afterwards,  in  (262  &z;c.),  show  how  his  results  can  be 
obtained  by  an  analytical  process;  noticing  the  smah  terms  that  he  has  neglected,  and 
which  require  attention  in  some  particular  cases. 

In  finding  the  orbit  of  a  comet,  we  have  given,  by  observation,  three  geocentric  longitudes 
and  latitudes,  together  with  the  times  of  observation  ;  and  from  the  solar  tables  we  have 
the  Sun's  longitudes  and  the  radii  vectores.  We  shall  use  the  symbols  in  the  following  table 
(9 — 29)  ;  most  of  them  being  like  those  which  are  given  by  La  Place,  [7Gl"',820'''&c.]. 
The  unaccented  letters  being  taken  for  thefirst  observation  ;  the  same  letters  with  one  accent 
for  the  middle  observation;  and  with  two  accents  for  the  third  observation.  We  have 
inserted  in  the  same  table  (30 — 45),  several  theorems  which  are  useful  in  these  calculations 
with  the  demonstrations  in  (40 — 130).  In  treating  of  this  subject  we  shall  refer  to  any 
line  of  [5994],  by  placing  the  number  of  the  line  in  a  parenthesis,  as  in  [5984  (2),  &;c.]. 


[5993] 

(71) 


(72) 


[5994] 


(1) 


(2) 


OiberSij 
metliod  of  I 
computing 
the  orbit  of 
a  Comet. 


(3) 
(1) 

(5) 
CO) 

(7) 

(8) 


792 


APPENDIX,  BY  THE  TRANSLATOR; 


[5994] 

(9) 
(10) 

(") 

(12) 
(13) 

(14) 

(15) 

(16) 

■       (17) 

(18) 
Symbols. 
(19) 

(20) 

(21) 

(29) 

(23) 

(24) 
(25) 
(26) 
(27) 

(28) 

(29) 
(30) 

(31) 

(32) 
Fundaniea- 
tal  equa- 
tions. 

(33) 


(34) 
(35) 
(36) 

(37) 
(38) 
(38') 

(39) 
(40) 
(11) 
(42) 


(44) 


t,  t',  I" ,  The  times  of  observation; 

©J  ^1  ©")  Longitudes  of  the  Sun,  differing  i8o''  from  those  of  the  earth  Jl,  A',  A",  respectively  ; 

a,  cl',  a".      Geocentric  Longitudes  of  the  comet  ; 

6,  8',  6",         Geocentric  latitudes  of  the  comet  ;  southern  latitude  being  considered  as  negative  ; 

Distances  of  the  earth  from  the  sun  ; 

Distances  of  the  comet  from  the  earth  ; 

Curtate  distances  of  the  comet  from  the  earth; 

Radii  vectores  of  the  orbit  of  the  comet  ; 

Heliocentric  longitudes  of  the  comet  ; 

Heliocentric  latitudes  of  the  comet  ;  southern  latitude  being  considered  as  negative  ; 

The  difTerences  of  the  heliocentric  longitudes  of  the  comet  and  the  earth  ; 

Longitude  of  the  ascending  node  of  the  comet; 

Inclination  of  the  comet's  orbit  to  the  ecliptic  ; 
Arguments  of  latitude  of  the  comet,  or  distances  from  the  ascending  node  counted  on  the  orbit  ; 

Arguments  of  latitude  of  the  comet  reduced  to  the  ecliptic  and  counted  from  the  ascending  node  ; 


R,  R',  R". 

îi>  Çi'>  î" 
h  f''  P"' 
r,  r',  r" , 

n, 
f, 

u,  u',  u", 
w,  w',  w", 

p^  =u  — l 
V,  V,  !)", 

c 

tang.6' 


The  true  anomalies  of  the  comet  ; 

The  perihelion  distance  of  the  comet  ; 

The  chord  of  the  path  of  the  comet  betvpeen  the  first  and  third  observations. 


m 


sin.(©'-a') 

p"=  M.f  ; 


[Approximnte"! 
value  of   JIf.J 


"tang.6"— m.sin.(©'— CL")       t'—t 
rS  =  /}2— 2fl.f.co3.(©— a)+f9.sec2.â  ; 
r"2  =  Ri'-i—2R".Mf,.cos.{Q"—o,'i)-\-M2.f^.sec''.6'i  ; 
c2  =  »-2-|-)-"2— 2iifl".cos.(Q"— ©) 

4-^2iJ".cos.(©"— a)+2Jl!fiî.cos.(i3— a")}-p 
+  5— 2>/.cos.(n,"— a)— 2JV/.tang.fl.tang.6"|.f2 


(A) 


(O 


sin.-w  =:  —  .  tang.9  ; 

p" 

sin.^"  =  !-77.  tang.S"  ; 

r" 

f.sin.(0— a)  . 

sin.Ê  =  ^ -^ ; 

r.cos.-ra- 

7-".C03..nr" 

cot.tu  =  tang.m".cot.Œ-.cosec.(/S"— ;S) — cot.(/3"— yg)  ; 
sin.(!o"-|-'=') 


SU3l. 


or, 


tan] 


/  g^-gx        sin.(.-4-^  _  (l!^) 

\  2         /  Sin.(OT"— ot)  *  V       2       / 


n  =  0 — V)  =  longitude  of  the  ascending  node  ; 
tang.?  =  tang.ra-.cosec.u)  . 
cos.u  =  cos.-ET.cos.îi!  =  cos  /sr.cos.(^ — n)  ; 
cos.u"=  cos.ot".cos.(/3"— n)  ; 


Xj  =  longitude  of  the  descending  node  =  i8o<^  -|-  fl  ; 
[?  =  Inclination] 


1 


(43)     tang. 


tang.Jt)  =  cot.ix—  (-Ttj    •  cosec.i;^  ; 


(44-,    tang.èu"  =  —  cot 


ta+fr)'. 


cosec.à;^;  ; 


(44") 
(45) 


tang.(èt)+Jx)  =  tang.(45''~J).cot.ix  ; 
D  =  r.cos.^iu  =  Perihelion  distance. 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  793 

[5994] 
We  shall  suppose,  in   the   annexed  figure   84,  that  s  is  the  place  of  the  sun  ;  a,  h,  c, 

the    places    of    the  comet  in   the   first,   second,    and  third  observations  ;  a',  b',  c',    the     i'^) 

corresponding  places  of    the   earth.      Draw  the   chords    ahc,  a'h'c,    intersecting   the 

radii    sb,  sb',  in    the   points  A,  A',  respectively;  then  by  Kepler's   first  law  [3G5'],  we 

have, 

(' — t  :  i" — t'  :  :  sector  sab  :  sector  sbc  .  (*') 

Now   if  we    consider    tlie    chord    «  c   as    a    very  small  quantity   of  the  first  order,   in 
comparison   with  the    radius    sb,    the   segment    hb  will   be  of  the  scco/k/ order.     In  this     (■is) 

Geometri 

case,  tlie  triangle   sac   will  be  of  the ^rsi  order,  and  the  elliptic,  hyperbolic  or  parabolic     JfiauoTof 
segment    a  be  ha   of    the  third  order;    so,   that  the   sector   s  abc    will   difier  but  very     (^g""*' 
little  from  the  triangle    sake.     In  like   manner  if  we   suppose   the   chords    ab,  cb    to  be 
drawn,  we  shall  find  that  tbe  sectors  sab,  scb,  differ  respectively  from  the  corresponding 
plane   triangles  sab,  scb,  by  quantities   of  the //»«/  order;  therefore  the   error  will  be 
but  very  small,  if  we   substitute   in  (47),  the  ratios  of  the   areas   of  these    plane   triangles,     (^"^ 
instead  of  the  ratio  of  the  areas  of  the  sectors.     Now  these  plane  triangles  have  the  same 
common    base  sb,  and   the   perpendiculars   let  fall   upon  it   from   the  points     a,c,     are 
evidently  proportional   to  ah,  ch,  therefore   their  areas  must  be  in  the  same  proportion; 
hence,  we  shall  have,  very  nearly, 


(51) 


(5S) 


(53) 


t' — t  :  t'' — t'  :  triangle  s«i  :  triangle  sc 5   ::  ah  :  ch. 

The  same  reasoning  may  be  applied  to  the  segments  of  the  chord  aV,  described  by  the 
earth  ;  therefore,  we  shall  have,  very  nearly, 

t'—t  :  t"—t'  ::  ah  :  ch  :  :  a'h'  :  c'h'  ; 

which  is  equivalent  to  the  supposition,  that  if  the  two  chords  a  c,  a'c',  be  described  with 
uniform  velocities,  in  the  time  t" — t,  by  a  fictitious  comet  and  j)ianet,  the  fictitious  bodies 
will  be  at  the  points  h,  h',  when  the  real  bodies  are  at  b,  b',  respectively  ;  and  it  is 
upon  this  hypothesis  that  the  method  of  Dr  Olbers  essentially  depends. 

We  shall  now  take  the  point  h' ,  as   a  centre,  and  shall  suppose  the  line  h's,    to  be 
continued  infinitely,  till  it  meets  the   concave  surface   of  the   starry  heavens,  in  the  point 
S,  figure  65,  representing  the    geocentric   place    of  the    sun  at  the   second  observation. 
Moreover,  we  shall    suppose    three  lines  to  be   drawn  through  A'  figure  84,  page  797,     (54) 
parallel  to  the  lines  a'a,  b'b,  c'c,  in  the  same  directions,  and   continued   infinitely  to  the 
heavens  in  the  points  A,  B,    C,  figure  S5,  representing  respectively  the  geocentric  places 
of  the  comet,  in  the  first,  second,  and  third  observations.     Through  the    extreme   points 
A,  C,  we  shall  draw  the  great  circle  CHAJV,  intersecting  the  ecliptic  SJV'm  the  point   .A''; 
also  the    great  circle  SB,  intersecting  the   arc  AC  in  H.     To  avoid  the  confusion  of 
having  many  lines  on  the  same  figure,  we  have  not  actually  drawn  these  three  lines  through     ,^^ 
the  point  A',  but  have  merely  marked,  in   figure  84,  page   797,  the   point  a'  of  the   line 
h'd'A,  and  the  point  c"  of  the    line  h'd'C;  supposing  h'a"  z=  a'a,  h'd'  =  dc.     Then  it  is 

VOL.  III.  199 


(55) 


794  APPENDIX,  BY  THE  TRANSLATOR; 

[5994] 

evident  from  this  construction,  and  from  the  proportions   between   tlio  lines  ah,  ch,  a'h',  c'h' 

(52),  that  the  right  line,  connecting  the  points  «",  c",  will  pass  through   the  point  h  ;  and 

'^^'     this  line  will  be  divided  by  the  point  h  into  the   segments  ha",  he",  which  have  the  same 

ratio  to  each  other,  as  ha,  he  ;  as  will  be  more  particularly  explained  in   a   similar  case  in 

(70,  &c.).     Then  as  the  line    shb,    when    viewed    from    h',    is  projected  on  the  concave 

surface  of  the  heavens,   in   the   great  circle    SB  ;    and  the  line    a" he',   when    viewed 

from  the  same  point  h',  is  projected  in  the  great  circle    AC  ;    it  follows,  that   the    point  h, 

which  is  the  intersection  of  these  two  lines  sb,  a"c",  must  be  projected   in  the   heavens  in 

the  point  H  where  the  two  great  circles  AHC,  SHB  intersect  each  other.     Therefore, 

H  will  be  the  geocentric  place  of  the  comet  in  the   heavens,  in  the  middle  observation,  if 

the  bodies  were  to  move  uniformly  in  the  chords  ae,  a'c'  and  the  comet  be  at  the  point  h, 

when  the  earth  is  at  h'. 


(38) 


(59) 
(60) 

(61) 


(02)         Now  if  we  suppose  P,  figure  85,  to  represent  the  pole  of  the  ecliptic  ;   °f  the  first  point 
of  Aries;  PAA',  PBB',  PHH,  FCC  circles  of  latitude  ;  we  shall  have, 


(G3) 


J  A'  =  è,     BB'=  ê',     CC'=  6"  ;     TA'  =  a,     rB'  =  a',     T  C"  =  a",     °fS=  ©', 

and  we  sliall  put  for  the  geocentric  longitude  and  latitude  of  the  point     H, 

cfW  =  a,  ;  HH'  =  L  ; 

,54,     also,  the  angles,  ASA!  =  b  ;         BSE'  =  b'  ;  CSC  =  b"  ; 

and  the  arcs,  SA^©'—^;         SB  =  0—a.' ;         .S'C'=  ©'— a". 

Then,  in  the  rectangular  spherical  triangle  ASA',  we  have, 

(65,  tang.^S^'='^^      [1345='^]; 

which,  in  symbols,  is  the  same  as  the  first  of  the  equations  (66)  ;  the  second  and  third  of 
these  equations,  are  found  in  the  same  manner,  from  the  rectangular  spherical  triangles, 
BSB',  CSC  ;  the  second  of  these  expressions,  is  evidently  equal  to  the  assumed  value 
of    m     (28); 

tangJ                          ,,              tang.â'  tang.4" 

(^6)     tang.è  = -r— T^.:^ r;        tang.i'==  -^— -~ —  =  m  ;         tang.i"=  ° 


(67) 


(68) 


(69) 


sin.(©'-a)'  °'  sin.(©'— a')  '  ^^  sin.(©'-a")- 

We  shall  suppose  in  figure  86,  that  the  paths  of  the  earth  and  comet  are  projeeted 
orthographically  vjion  the  plane  of  (hat  circle  of  latitude  which  is  perpendicular  to  the 
radius,  drawn  from  the  sun  to  the  earth  at  the  time  of  the  middle  observation  ;  or  in  other 
words,  that  the  plane  of  projection  is  perpendicular  to  the  line  b'h's  figure  84  ;  so  that 
the  point  h^,  of  figure  86,  is  the  projection  of  this  line,  or  of  the  three  points  b',  h' ,  s, 
upon  the  plane  of  this  figure.  AVe  shall  suppose,  that  the  points  «,  ,  c, ,  .^, ,  C,  , 
represent,  respectively,  the  projections  of  the  places  of  the  earth  a',  c',  and  of  the  comet 
a,  c,  at  the  times  of  the  first  and  third  observations  ;  also  I-l„  the  projection  of  the 
point  h;  so  that  the  points  S,  A,  H,  C,  in  figure  85,  correspond  respectively  to 
the   points    s,  A^,  H,,    C,   in   figure  86.     Then  it  is  evident  from  the  principles   of  the 


I 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 

PPolc  of  theEcUpnc 

orthographic  projection,  that  the    lines  rt,f,, 

.4, C, ,    are  divided  in  the   points  /(,,  //.;,  in 

tlie  same  proportion  as  the  lines     n't',  «c,  in 

figure  84,  are  by  the  points  /(',  h.     Therefore, 

if  we  draw  tlie  line  ^,.î,  ,  parallel  and  equal 

to  (7, /îj;  C,  C^ ,  parallel    and  equal    to    e,/i,; 

then   join  //„  C.,  H,A„ ,  we  shall  have,  as  in 

(52),  very  nearly, 

t'—l  :  t"—t'  ::A,H,:  C,H,  :  :  A,.^„  :  C,C„. 

IN'ow  by  construction  the  angles  C,C^H,  A^A^H,,  are  equal,  and  as  the  sides  about 
these  angles  are  proportional,  in  the  triangles  C^C^H^,  A^A^M^ ,  therefore  these  triangles 
are  similar,  and  the  angle  A^H„A^  :^  the  angle  C^H„C„;  consequently  the  three 
points  A„,H„,C„,  are  situated  in  a  straight  line  ;  \^hich  is  divided  by  the  point  H„,'m 
the  same  proportion  as  the  line  A,C^  is  divided  by  the  same  point;  so  that  we  shall 
have,  as  in  (52), 

t'~t:  t"—t'  ■.-.AJL  :  CM.. 


795 

[5994] 


(70) 


(71) 


(T2) 


(73) 


(74) 


From  the  above  construction,  it  is  also  evident,  that  the  line    h^A..  is   equal  and  parallel 
to  a, .^,  ;  and    h^C„,  equal   and   parallel    to    c^C^;     so   that  if   the  lines  ^j ./2, ,  A,  C,  be    ('S) 
continued  infinitely,  they  will  represent  the  projections  of  the  lines  liA,  h'C  (55),  drawn 
in  figure  85,  from  the  centre  of  the  sphere  h'  to  the  geocentric  places  A,B,C,  of  the  comet,     P^) 
in  the  starry  heavens,  at  the  first  and  third  observations.     In  like  manner  h^  J/,  represents 
the  projection  of  the  line    h'hH  figure  84,  drawn  from  the  centre   A',  through  the  point   h, 
towards  the  point    H   in  the  starry  heavens.     The  line    «,Ci,  figure  86,  continued  to    A,,     <■"''' 
represents  the  projection  of  the  ecliptic,  upon  which  we  shall  let  fall  the  perpendiculars  A„A^, 
A^a^,HJi^,  C^c,,  C„Cy     Then  it  is  evident,  from    the  constmction,   that     a^a^^k^A,    (78) 
is  the  projection  of  the  curtate  distance     p     at  the  time  of  the  first  observation  ;  and  as  the 
geocentric  longitude   of  the  comet  is  then  equal   to     a.,     and  the  longitude   of  the  axis    (79) 


796  APPENDIX,  BY  THE  TRANSLATOR; 

[5994] 

drawn  through  a, ,  perpendicular  to  the  plane  of  the   figure  is  ©',  the   inclination  of  the 

line    p    to  this  axis  is    0' — a  ;  consequently  this  projection  of    p     is  represented  by, 

(80)  a,a,  =  h.  A,  =  p.sin.(©'— a). 
In  like  manner  the  projection  of    p"     is, 

(81)  qC3  =  A.C3  =  p".sin.(©'-a"). 

Again,  as  the  line  .S'A'  figure  85,  is  perpendicular  to  the   plane  of  projection   in  figure  86, 
the  angles   formed  about   the    point    »Si    figure  85,  will  be    projected  about  the   point  h  , 

(82)  figure  86,  without  any  alterations  in  their  magnitudes  or  relative  positions  ;  so  that  the 
angle  ASA'  figure  85,  will  be  projected  into  AJi^A'  in  figure  86,  and  so  on  for  the  other 
angles  ;  hence  we  shall  have,  by  using  the  same  symbols  as  in  (64)  ; 

■  (83)    AJi^A„_  ==  b  ;     HJi,H^  =  V  ;      CJi,  C._  =  h"  ;     AJi.H,  =  b'— h  ;     C.h^H,  =  h"—  b'. 

Now  in  the  rectangular  plane  triangles  A^h^A^,  CJi^C^,  we  have  by  using   the  values 
(80,31,83), 

(84)  h^^=_Ml_  _  P-sin.(©'-a).  ^^  ^  _         KC         _  p".sin.(©'-a")   ^ 

'    "       cos-A^h^A„  cos. 6         '  '    '       c  os.C^h^Cr,  cos. 6" 

In  the  plane  triangle  A,HJi^  we  have, 

(85)  sm.A„HJi^   :  sm.AJi.H.,  ::  h,A„  :  A^_H„; 

hence  we  get  the  first  expression  (86),  using  for  brevity, 

(85)  sin.  jH":=  sin.^^iTjAj  =  sin.CjH,A,  ; 

and  by  substituting  the  symbols  (83,84)  in  its  second  member  we  get  the  second  expression 
(86).     In  like  manner  from  the  triangle    C^H^h^  we  get  the  expression  (87)  ; 

(86)  A„H,.sm.H=h,A„.sm.A„h,H  =  ^'^'"'^®,~-^ .  s\n.(b'—b)  ; 

cos. 6 

(87)  CM. .  sin.H  =  h,  C„  .sin.  CJi.H^  =  j!:^"-(©'— "■')  _  si„. (i"_  m 

cos. 6 

Dividing  the  equation  (87)  by  (86),  then  substituting  in  the  first  member,  the  expression, 

CM.         t"—t' 


A„  H„         i' 


(-^4); 


putting  also  p"  =  J\Lp,  as  in  (29),  we  get  the  approximate  values  of  M  (92).  Developing 
the  first  members  of  (89,90),  by  [22,34']  Int.,  and  substituting  the  values  (66),  we  get 
successively, 


co:mputation  of  the  orbit  of  a  comet. 

sin.(i' — b)  =sin.6'.cos.i  —  cos.ô'.sin.i  =  cos.i.cos.t'.  (tang.6' — fang. 6) 


=  COS. J. COS. J'. 


tang.^      \ 


s.n.(©'. 
sin.(i" —  b)  =^  sin.i".  cos.i'  —  cos. 6".  sin. 6'=  cos. 6'. cos. 6".  (tang. 6" —  tang. J') 

,,  ,,,  /       tang.â" 

=  cos.6'.cos.6".    -^—, — .  —  t, 

Vsni.(©'-a") 

Substituting  the  values  (S9,90)  in  M  (92),  and  rejecting  the  factor  cos.b.cos.b'.cos.b'', 
which  occurs  in  the  numerator  and  denominator,  we  finally  obtain  the  approximate  value  of 
J\I     (93)  ;  which  is  of  tlie  same  form  as  in  (30)  ; 

t"—i'     cos.b".sm.{b'—b)       sin.((v)'_cL) 


M 


I'—t     cos.b.s\n.{b"—b')      sin.(©'— a") 
t" — t'       m.sin.f©' — a) — tang.é 


[Approximate"! 
ViiiUL'  of     .V.J 


f  t 


ig.ô" — 7n.sin.(@' — a") 

We  shall  show  hereafter,  in  (306,  &c.),  iiow  this  approximate  value  of  JH  may  be  corrected 
for  the  error  of  the  hypothesis  (50),  where  the  ratio  of  the  areas  of  tiie  triangles,  is  used 
instead  of  that  of  the  sectors.  Again,  we  have,  in  the  right  angled  spherical  triangle 
BBS,  figure  85,  page  795, 

C0S.SJ5  =  cos.SB'.  cos.BB'  ==  cos.(©'— a').cos.ô'     [IS^S^'J  ; 

and  this  evidently  represents  the  cosine   of  the  angular  distance    of  the  sun   and   comet 

sb'b  =  SB     figures  S4,  85,  in  the  second  observation.     In  like   manner,  by  decreasing  by 

unity,  the  accents  of  the  symbols,  so  as  to  make  them  correspond  to  the  first  observation, 
we  get, 

cos.  s  a' a  =:  cos.  (©  —  a)  .  cos.  Ô  . 

Now  in  this  plane  triangle  sa'a,  we  have,  sa  =  r, 
sa'  ■==  R,  aa'  =  p. seed,  and,  by  using  [62]  Int. 
we  obtain  the  expression  (9T),  which  is  easily 
reduced  to  the  form  (98),  being  the  same  as  the 
first  equation  of  La  Place's  method  [806]  ; 

r^^.^^-2R.(p.secJ).\eos.{Çî)-a.).cosJl+{p.sec.êf 
=iJ2_2iJ.p.cos.(©— a)4-,A  sec^.^. 

This  last  expression  is  the  same  as  the  value  of 
r^,  (31),  corresponding  to  the  Jirst  observation. 
If  we  add  two  accents  to  the  symbols  of  this 
expression  we  get, 

r"^=R"^—2  R"J'.co5.  (©"—a") +p"2.sec2.«3"  ;     ^"'^ 
VOL.  III.  200 


797 

[5994] 


(90) 
(9)) 

(93) 
(93) 

(93') 

(94) 

(95) 

(9C) 
(9C-) 


(97) 
(98) 


(90) 


798 


APPENDIX,  BY  THE  TRANSLATOR; 


'-^      '       which,  by  substituting     p"  =  iVi.p     (29),  becomes  as  in  (32)  ;  corresponding  to  the  third 
observation. 

We  shall  now  suppose,  fora  moment,  that  the  place  of  the  comet  at  the  first  observation, 
is  determined  by  three  rectangular  co-ordinates  x,  y,  z,  whose  origin  is  the  centre  of 
the  sun.  Tiie  axis  of  x  is  drawn  in  the  plane  of  the  ecliptic,  towards  the  first  point  of 
Aries  ;  the  axis  of  y,  is  drawn  in  the  same  place,  towards  the  first  point  of  Cancer  ;  the  axis 
of  z,  is  perpendicular  to  the  ecliptic,  and  directed  towards  its  northern  pole.  In  like 
manner,  we  shall  suppose,  that  x',  y',  z',  represent  the  co-ordinates  of  the  comet,  at 
the  second  observation  ;  also  x",  y"  z",  those  at  the  third  observation  ;  then  it  is 
evident,  from  the  principles  of  the  orthographic  projection  [118],  that  if  c  represent  the 
line  or  chord,  between  the  places  of  the  comet  at  the  first  and  third  observations,  we  shall  have 
the  first  of  the  expressions  of    c^     (106)  and  by  developing  and  substituting, 

r2=.ï2^y2_j_,a.  r""~  =  x""" -^  y"^  +  z"^  ; 

it  becomes  as  in  (107)  ; 

c^=(x''_a:)2-f(y"-y)2+(^"-=)2=(x"2-fy'S+~~"^)+(^^+/+^=)-'2.(x^^"+y2/"+r^") 


(100) 
(101) 

(102) 
(103) 
(104) 


(105) 

(106) 
(107) 


(108) 

(109) 


(110) 

(HI) 
(112) 

(113) 
(114) 


Now  we  have,  as  in  [762,768], 

X  =  R.cos.A-\-  p.cos.a  ; 
a;"  =  JÎ".cos.^" -f  p".  cos.a"; 


•■"■^+r^-2.{xx"+yy"+zz"). 

y  =  R.sm.A  -\-  p. sin. a,  ; 
y"=.ii".sin.^"-f  p".sin.a". 


p.tang.é. 
■■  p".  tang.â". 


(115) 


Substituting  these  values  in  the  first  member  of  (110),  we  get  its  second  member,  and  by 
successive  reductions,  it  becomes  as  in  (112)  ;  using  the  values  of  A,  A"  (10); 

xa;"+y/  =  iî.iî".(cos.y4.cos.„2"-f-sin.^.sin../2")4-iî".r.(cos.^".cos.a-fsin.^".sin.a) 

-\-  i?.p".(cos.^.cos.a"-|-sin.^.sin.a") -f-p.p".(cos.a.cos.a"-f-sin.a.sin.a") 

=  iï.iî".cos.(^"— ^)-|-jR".p.cos.(^"— a.)-Liî.p".cos.(.4— a")+p.p".cos.(a"— a) 

=/î.iî".cos.(©"— ©)— iî".p.cos.(©"— a)— JJ.p".cos.(©-a")-(-p.p".cos.(a"— a). 

CoTiiet  tPi 

^  Substituting  this  and  i;;"  =  p.r".tang.ltang.ô"  (108,  109), in  (107); 

and  then  putting  p"  =  ^lp.     (29), it  becomes  as  in  (33),  the  terms 

81    being  arranged  according  to  the  powers  of    p.    We  have   as   in 

[5858]     c  =  r.sin.lat.  or  c  =  r.sin.ra    (18);  putting  this  equal 

to  the  value  of  z  (108),  we  get    sin.w    (34),  corresponding  to  the 

first   observation,  and    in    like  manner    we   obtain    for   the  third 

observation    sin.jr"    (35).     In  fig.  87,  if  S  be  the  place  of  the  sun, 

C,  that  of  the  comet,and  Tthat  of  the  earth,  at  the  first  obervation  ; 

g^^^  C,C  a  line  drawn  from  the  comet  Cj,  perpendicular  to  the  plane 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


799 

[5994] 

(116) 


of  the  ecliptic  ;  we  shall  have  in  the  plane  triangle,   STC, 

TC:^?,      SC^  r.cos.zi,       CST  =  e,       STC  =  ©  —  a  ; 
and  since, 

SC  :   TC  ::  sin.STC  :  sm.  CST  ;  (in) 

we  shall  have,  in  symbols, 

r.cos.-a  :  p  ::  sin. (©  —  a)   :  sin.s;  (U3) 

whence  we  obtain  sin. s  (3G),  corresponding  to  the  first  observation;  and  by  putting  two 
accents  upon  the  symbols,  we  obtain  the  similar  expression  of  sin.s"  (37),  corresponding 
to  the  third  observation. 


In  figure  88,  NA'C  represents  the  ecliptic,  A,C,  the  heliocentric  places  of  the  comet  at 

the  first  and  third  observations  ;  A',  C,  these  places  reduced  to  the  ecliptic  ;  N  the  ascending 

node  of  the  comet's  heliocentric  orbk  NAC.     Then  in  the  rectangular  spherical  triangle, 

NJ'J,v:e  have  cot.AJS^A'   =   cot.^^'.sin.iV^'      [1345  31J  ;      or,    in  symbols, 

cot.(p  =  cot.  w.  sin.w,   which  is  easily  reduced   to  the  form   (40).     In  like  manner,  in  the 

triangle  NCC,  we  have,  by  putting  for  a  moment,    p"  —  (3  =  2p„  and  NC  =  tv  -\-  2(3i  ; 

cot.<p  =  cot.i3".sin.(w  -\-  2|3i)  =  cot.w".{sin.w.cos.2(3,-fcos.w.sin.2j3i.}.     Putting  these  two 

expressions  of   cot.ç    (120',  122)  equal  to  each  other,  and  dividing  by     sin.w.sin.2(3,.cot.ra", 

we  get,    tang. •!3".cot.w.cosec.2p.  =  cot.2p, -f  cot.  w,     whence  we  get     cot.w    (38).     This 

expression  may  be  reduced  to  the  form  (38')  ;  which   is  rather  more  convenient,  in  using 

logarithms.     For  we  have,  in  the  triangles,  iV,^^',    NCC; 

tang. -53 
tang.çi  =  -r^—  ; 
s\n.io 

88 


(119) 

(ISO) 

(120') 
(121) 
(122) 
(1220 


tang.  (? 


tans.w 


sin.(i(;4-p"— /3)    ' 


(122-) 


and  by  putting  these  two  expressions  equal  to    27hac^ 

each  other,  we  get  the  first   equation  (123').     ^ 

Putting  for    brevity,     m'j=?=  w  +  I- (p'' — (3)  =  "'+P,,    we  get  the  second  form  in  (123')     (123) 

and,    by  development  we  obtain   the   third   form.     From  this  last  expression,  we  easily 

.  cos. ta".  COS. Î3 

deduce  (124),  and   by  multiplying  it  by    tang./3,  . t, ;   we  get  the  first  expression 

cos.ra  .  cos.w 

(124'),  which  is  easily  reduced  to  the  second  form,  which  is  the  same  as  (38'), 


tang. -a"  sin.(w  +  p"  —  p)         sin.(w,  -|-  p^)         sin.Wj.cos.Pj  +  cos.Wj.sin.p, 


IV.  sin.(îfj  —  Pj) 

2sin.M, .  cos.pj  tang.M'i 


tang.w 

tang.sr"  +  tang.ra 

tang.ra"  —  tang.CT  2cos.Jfi  .sin.Pi  tang.^ 

sin.-n''.cos.«  -\-  cos.-n".sin.ra 


sin.t«,.cos./3j  —  cos.iVi.sin.p, 


tang.jfj  = 


sin.ra  .cos.nr  —  cos.w  .sm.ar. 


sin.('n"  4-  w) 
^^"S-P'  =  sin.(."-^]-'^"S-^'" 


(123') 


(124) 


(124) 


800  APPENDIX,  BY  THE  TRANSLATOR;  1 

[59941 

•^    Again  in  tlie  triangles     NAA',     NCC,     fig.  88.  we  have 

(las)  cos.iV^  =  cos.^^'.cos.iV.f  ;       cos.jYC  =  cos.CC\co3.iYC'    [1345^'], 

which  in  symbols,  becomes  as  in  (41,42).     These  values  of  it,  m",  give, 

(126)  X  ^=  ""  —  "  =  ^'^^  AC  ; 

adding  this  to     v     we  gel     v"  =  v  -\-  x-     Then  the  formvda  (45),  which  is  the  same  as 
[5986(4)],  gives, 

(137)  D  =  ?-.cos.^Ju  =  r".  cos.^i.(v-|-  x)  5 

hence, 

/r\4  cos.i.(w4-v)        cos .  il) .  cos.  J  y — sin.  Jy  .  sin.  fv  ,  ,      .     . 

(1-28)    [-j;Y  =         ^^  .  = -^ = ^  =  cos.ix  — tang.iu.sin.ix- 

V  /  cos.^y  cos.Ji; 

(128)  Dividing  this  by  sin.Jx»  we  get  the  value  of  tang.iy  (44).  In  the  same  way,  we  may 
obtain  the  expression  of  tang.|w"  (44')  ;  or  more  simply,  by  changing  r,  v,  u, 
corresponding  to  the  first  observation,  into  r",  v",  ii",  which  corresponds  to  the  third  ; 
by  which  means  %  (24),  changes  into  —  x  .  The  expression  (44),  may  be  reduced 
to  the  form  (44"),  by  putting, 

(129)  tang.l  =  iy^  4      (4-'^)  ; 

by  which  means  it  becomes, 

tang.? 

tang.^w  ==  cot.lx r-^-  ,         or,  tang.|  =  cos.ix  —  sm-sX-tang.ii,'  ; 

(129')  sm.J-x 

hence  we  get, by  successive  reductions,  and  using  [1,6,31,29]  Int.,  the  following  expressions, 

1  —  tang. I         1  —  cos.i-x  +  sin.i-x.tang.^^u  2sin.^2~X  +  Ssin.ix-^os.^x-'ang.v^y 


(130) 


1  -|- tang.l         1  -|- cos.^x  —  sin-^x-tang-J^u       2cos.^,[x —  ^sin.^x-cos.^x-'ang.iv 


tang.J^v  4-  tang. il) 
C130')  =tang.ix-  ',       T   .        1    =tang.ix-tang.(^i;4-ix)- 

1  —  tang.J^x-tang.^w 

Substituting     1  =  tang.4.5'',     in  the  first  member  of  (130),  and  then  reducing,  by  means  of 
(30)  Int.  it  becomes, 

tan£!;.45''  —  tang.|  ,      , 

(130")  ~ _    '^^    =  tang.(45''  —  |)  ; 

1  4-  tang.45'' tang.l  °^  ^ 

hence  the  expression    (130')    becomes  as  in  (44"). 

We  shall  now  proceed  to   illustrate  these  formulas  by  an  example  in  (1T3,  Sic).     The 

(131)    data   being    as  in  (174 —  17-5).     With    these,  we  can   compute  in    (176  —  181),    the 

coefficientsofthe  fundamental  equations  (31,32,33),  as  in  (182 — 186).  From  these  equations , 


whence  we  find,  by  inspection,  in  Table  II,  T=^27<'^J",  instead  of  the  real  value  by 
observation  T  =  8^"^^  ;  and  as  this  is  three  times  toj  great,  we  may  decrease  p  in  that 
ratio,  and  take  for  a  second  value     p  ^ +•     This  gives  in  (184,186), 

7-2  _|.  /'2  =  1^747  .         c2  =  0,0374, 
VOL.  III.  201 


(135) 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  801 

[5994] 
by  llie  process,  which   is  explained    in   (134 — 163),   we  may  compute  the  values   of    p,     ;i32) 

r,  r".     in  successive  approximations  with  the  help  of  Tables  I,  II,  as  in  (167 — 191)  ;    the 

argumenlstobe  used  in  Table  II,  being  the  sum  of  the  radii    r  -|-  r"  at  the  top  of  the  page, 

and  the  chord  c  at  the  side.     Having  obtained  these  approximate  values  of  p,  r,  r",  we  can    ,,33, 

deduce  from  tlicni  the  approximate    elements  of  the  orbit,  as  in  (193 — 20.5).     The  chief 

difficulty  in   this  solution,  is   in   finding   the  value  of  p,   which  will   satisfy  the   equations 

(lS-2, 183,186),  or,  as  they  are  called,  {A),  (B),  (C)  ;    to  which  we  may  also  annex  the     (134) 

equation  (X)),  or  the   sum   of  tlie   equations  (A),  (B),  which    represents  the   value   of 

,.2_j_  ^"2_     The  method  of  operation,  to  find   the  valu 3  of    p,  is  explained  in  the  precepts, 

in  the  four  first  pages  of  Table  II,  to  which  we  may  refer,  observing  particularly  the  directions 

at   the  bottom  of  the  fourth  page,  to  vary  p  in  the  successive  operations  by  some    aliquot     (135) 

part  of  its  last  value,  represented  by    -.p;      p     being    an    integral   number,    positive  or 

negative;  by  this  means  any  term     A,     depending  on  the  first  power  of    p     is  augmented 

1  2  1   /2      \ 

by     -.A.     and  if  it  depend  on     p^,     it  is  augmented  by  the  quantity     --A-] .(-.A). 

P  P  ^p\p      J 

We  may  also  observe,  that  in  making   the  first  rough  estimate  of  the  value  of    p,     we  can 
use  with  advantage  the  two   equations  (C),  (D),  or  the  values  of     r^ -\- r''~,    c^  ;     found     "^^' 
to  one  or  two  places  of  decimals.     In  this  process  we  must  enter  Table  II  with  the  argument 
,.2  _j_  ,."2     at  ti^g  bottom,  and     t^     at  the  right  hand  side  column.     In  this  case  we  have      ''^"' 
only  two  equations,    {C),{D),  to  satisfy  ;  instead  of  the  t/iree  equations    (A),  (B),(C)  , 
required   in  the  general  and  more  accurate  process.     Most  commonly,  we  may,  for  a  first 
hypothesis,  take  p  =  1  ;  and  if  the  resulting  time  T,  deduced  from  Table  II,  be  too  great.     C^b) 
we  must,  in   general,  decrease  proportionally  the  value  of    p  ;     and  in  one  or  two  trials, 
without  the  trouble  of  taking  any  proportional  parts,  and  with  a  very  few  minutes  labor,  we 
can  get  a  pretty  close  approximation  to  the  value  of  p.     When  this  is  obtained,  we  can  use 
it  with  the   equations  [A),  (B),  (C),  in  getting  the  correct  value  of   p,    by  the  process 
explained   in   page  2  of  Table  II,  or  by  the  similar  calculation   in   (153 — 163).     In  the 
examples  which  we   shall  give   in   (207 — 242),  for  finding     p,     we   have   neglected  the 
consideration  of  the  equation   (D),  but  it  may  not  be  amiss  to   show  the   advantage  of 
using  it,  by  applying  it  to  these  examples.     Taking  therefore  the  first  example,  and  usino- 
the  equations  (D),  (C),  (184,186),  we  find,   that    if  we   put      p  ^  1,      and   use  two 
places  of  decimals  we  shall  get 

,.a  _|_  ^/ 3  ^2^02—  1,50  +  2,01  =  2,53  ;         £2  =  0,02  —  0,11  +  0,50=0,41  ; 


(139) 


(HO) 


(141) 


(142) 


(143) 


B02  APPENDIX,  BY  THE  TRANSLATOR  ; 

r 59941 

whence      T  =  "''"-'^G  nearly.     This  must   be    increased  a  little,  because  the  time  is   too 
(144)    small,  as  we   have    clone  in  (189).     Again  if  we  put     p  =  1,     in  the   second   example, 
(207, 8ic.)   we  shall  get,  from  (210,  209), 

,•2+  r"2  =  4,71  ;         c2  =  0,6S  ; 

which  gives,    in  Table  11,      T  =  42'i"Js     instead  of     ll''-'')%9734.     We  may,  therefore, 
C'*^'     for  a  second  supposition,  put     P  =  4»     because   these  two  values  are  nearly  in  that  ratio. 
Substituting     p  =  i     in  (210,209)  we  get, 

7-2  4- r"2  =  2,42  ;         c^^  0,104; 

hence  we   get   in    Table   II,      J"^  I4<iay3     nearly;    so   that     p     must   be   still   further 
(146)     decreased  ;  and  the  value  assumed  in  (212)  is  |.     In  Example  III,  (216, &,c.),  we  have 
by  putting     P  =  1,     in  (219,218), 

r3  +  r"2  =  4,98;         c^  =  0,91  ; 

whence      T  =  49''"^"     instead  of     lO''"^"  ;      so  that  for  a  second    value    we  may  take 

f  =  -1,     which  gives, 

r2  +  r"2  =  1,79  ;         c^  =  0,009  ; 

,j47)     whence      T  =  S'^"-",'-     This  is  much  loo  small,  therefore  we  may  take    p  =  i  ;     hence, 

r3  +  ,-"s  =  1,89  ;         0^  =  0,050; 

whence     T  =1  9'^"^%     which  must   be   increased  a  little  as  in  (222).     In   Example  IV, 
(226,  &tc)  we  have,  by  putting     p  =  1,     in  (229,228), 

r^^- ?-"2=l,9S;         c2  =  0,12; 

whence     r=  14''''>' ;     which  is  nearly  four  times  too  great,  therefore  we  may  take  for 
(148)    the  next  operation    p  =  j,    as  in  (231).     In  Example  V,  (235,  Sic),  we  have,  by  putting 
p=l,     in   (230,235), 

j-s  +  r"2  =  4,39  ;        c^  =  0,]6; 

whence     T=20'^''>'%     which  is  more   than   double    the   actual  value,  we  may  therefore 
(H9)     assume     p  =  I     as  in   (237)   for  the  next  operation.     In   Example   VI,  we   have  by 
putting     p=l,     in  (240,239), 

,•24-  r"2  =  1,27  ;         0^=0,45  ; 

whence  T=  21'''^^^;  which  is  twice  the  actual  value;  we  may  therefore  take  for  the 
next  operation  p  =  à)  as  in  (241).  What  we  have  here  stated  will  serve  to  show  the 
method  of  using  the  equation  (D).  We  shall  now  proceed  to  the  explanation  of  the 
process  with  the  equations  (A),  (B),  (C)  ;  and  it  will  suffice,  for  this  purpose,  to  explain 
(153)     part'cularly,  the  calculations  in  the  first  example  in  (173 — 206). 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  803 


(IÔ3) 


(154) 


(155) 


(156) 


(157) 


In  making  the  calculation  of  p,  from  the  equations  (A),  (B),  (C),  or  (182, 183, 18G) 
of  the  first  example,  we  have  placed,  in  the  first  column  of  the  table  (187—191),  the 
successive  values  which  are  assumed  for  p.  The  second  column  contains  the  corresponding 
terms  of  /",  deduced  from  the  equation  (A),  in  the  third,  the  value  of  r"'^,  deduced 
from  (Z?;  ;  tiie  fourth  the  value  of  c-,  deduced  from  (C).  In  the  fifth  column  are 
the  corresponding  values  of  7-,  »■",  c,  deduced  from  r~,  ?■"-,  t^,  by  means  of  Table  I  ;  and 
in  the  sixth  column  is  the  resulting  value  of  T,  deduced  from  Table  II.  Thus  by  putting 
p^l  in  the  equation  (.2),  we  find  that  the  terms  become  7--^l,014—O,2S8-|-l  ,103=1,829, 
as  in  column  2;  and  with  this  value  of  i~,  we  get  r=  1,35,  in  Table  I.  In  the 
same  way,  we  get,  from  (5),  (C),  the  expressions  ?"  =  0,84.;  c  =  0,64  ;  then  with 
r-\-r"  ^=  2,19  and  c  =  0,G1,  we  obtain,  by  the  mere  inspection  of  Table  II,  r=27'^">% 
nearly.  This  time  being  about  three  times  as  great  as  the  actual  value  by  observation, 
T  =  B'''"'',  we  may  take  for  a  second  hypothesis  p^  ^  ;  and  by  repeating  the  operation  get 
T^  7'''>%6GO.     The  calculation  of  the  coefficients  of    p,  p^    in  these  equations  is  made  in  ^ 

columns  S,  9,  10,  conformably  to  the  precepts  in  pages  I,  2,  3,  4,  of  Table  II;  and  the 
results  are  transferred  tocolumns  2,3,  4.  In  going  through  these  calculations,  we  have  always 
varied  p  by  an  aliquot  part  -  .  p  of  its  last  value,  according  to  the  precepts  in  the  table 
and  in  (135).  Thus  we  have,  in  the  first  instance,  taken  p=l  (187),  then  p=^  (188)  ;  to 
this  second  value  J^j  part  is  added,  for  the  next  operation;  and  as  this  is  found  to  be  too  (IM) 
great,  it  is  decreased  by  ^^^  part  ;  finally  this  last  value  is  increased  by  ^J^^  part  or 
0,0004,  multiplied  by  its  last  value  ;  and  then  the  resulting  expression  of  T  becomes  (JC2) 
gjajs^  agreeing  with  the  observations.  Similar  processes  are  used  in  the  other  examples, 
as  may  be  seen  by  inspection  of  the  calculations,  without  any  particular  explanation. 


(159) 


(ICO) 


(163) 


(165) 
(106) 


In  the  first  example  (173 — 206),  we  have  gonethrough  the  whole  calculation  (176 — 181) 
for  finding  the  coefficients  of  the  equations  {A),  (B),  (C),  (18-2 — 186)  ;  and  deducing  from 
them  the  values  of     p,     r,     r'     (187 — 192).     From  these  last  quantities  we  have  finally     (i64) 
deduced  the  elements  of  the  orbit,  as  in  (193 — 205).     This  one  example   will  suffice  for 
the  illustration  of  the  method  of  calculating  the  coefficients  (176 — 181),  and  the  computation 
of  the  elements  (193 — 205)  ;  but  for  the  sake   of  explaining  more  particularly  the  uses  of 
Tables  I,  II ,     we  shall  insert  several  examples  of  the  computation  of    p,     r,    r",    similar 
to  (187 — 192),  from  the   fundamental  equations  (A),  {B),  (C),  corresponding  lo  difierent 
comets  and  shall  select,  for  this  purpose, some  which  have  been  already  calculated  by  Olbers,     (la?) 
Delambre,  Ivory,  Sic.     We  may  remark,  that  if  any  one  of  the  coefficients  of  the  erjualions 
(A),  {B),  (C),  be  negative,  we  may   add  its    arithmetical  coniplement   to   I OfiQOOO,  and    (les) 
then  reject  this  last  quantity.    Thus,  in  finding  the  first  value  of    r-.     in  the  following  table 
(187);  instead  of  using     1,014—0,288+1,103     we  may  take,  (leo) 

1,014  +  9,712  +  1,103  —  10,000  ; 
and  as  each  figure  of  the  arithmetical  complew eut  can  be  taken  separately,  tvhilc  performing    ^^^^^ 
the  process  of  the  addition  of  these  quantities,  toilhout  the  trouble  of  actually  writing  down 
the  figures  of  the  arithmetical  complement,  u-e   can   make   this  addition,  by   one   operation^ 
notwithstanding  the  difference  of  the  signs  :  by  this  means  the  calculation  is  somewhat    (i72) 
abridged. 


804 

[5994] 

(173) 

(171) 

(175) 


(1750 


APPENDIX,  BY  THE  TRANSLATOR  ; 


EXAMPLE     Ï. 

This  example  is  the  same  as  that  of  Dr  Olbers,  in  page  54  of  his   Mhamllung,  &c.,  in   which    he    gives   the 
computation  of  the  orbit  of  the  comet  of  1769,  from  the  observations  of  September  4'''',  8"',  12"',  1769. 

©  long.  Comet's  geo.  long.  Com.  geo.  lat.  South.  log.  ©  dist.  earth. 

1769  Sep.  4'"  14'';    ©   =  i62''42"'o5»  ;  a    =    So-'Se'»!!';  9    =  —  17*  5im  3g.  ;  jog.R    =o,oo3i32; 

8'' 14'';     0'  =i66''35"'3i';  a'   =  loi'^oo'"  54^  6'  =  —  22'^  oS"  02»  ;  log.B'   =  o,oo2665  ; 

12''  14'';     ©"  =  I70''29"'20s;  a"  =  124'' 19™  22' ;  Ô"  =  —  23''43'"  55' ;  log.iî"  =  0,002184  . 

Hence  we  deduce, 

©  — ci.  =  8i<f45»' 54";    ©  —  a"=  38'' 22™  43»  ; 

©' —  a  :^  SS-J  39»  20»  ;   4g)' —  a' =  65*  34™  37' ;    ©'  — a"=  42*  le^cg»; 

©"— a  =  89'' 33m  ogS    ©"— a"=  46'' 09"  58»  ;    ©"— ©  =   7'' 47""  1 5»  ;     y."  —  cl  =  43-' 23"  11». 

log.flâ  =  0,006264  ;     log./J"a  =  o,oo4368  ;     log.2iJ  =o,3o4i62  ;    log.2iJ"  =  o,3o32i4  . 

In  this  example  the  ffieeii's  geocentric  latitudes  being  smith  are  considered  as  nc^a<i«e  ;  and  the  rules  fur 
the  signs  of  t lie  angles  ISggo  (23,24,  25)]  are  to  he  ohseived  in  finding  the  coefficients  uf  ail  the  terms  of 
the  fundamental  equations  (28 — 33). 


I.       CALCULATION    OF    THE    THREE    FUlSfD.lMENTA  L    EQUATIONS    (3[,32,  33). 


(176) 


(177) 


To  find    m,     M    (28,  3o). 

6'  tang.  9,608237,, 

©' — a'  cosec.  ,040712 

m  log.     9,648949,, 

— sin.(©'— a")  log.     9,827766" 

0,29972  log.     9,476715 
(ang  6"=— 0,43963 


(178) 


— o,i3ç9i^Denomin.  of  Jil 

m    log.    9,6489491 
©'—a,    sin.    9,998750 

—0,44432  log.  9,647699» 
— tang. 6^=0, 32 224 


(179) 


i\um.of3/=-0, 12308  log.   9,086644 
Den.  ot  M   log.co.ar.o,854i5i" 
t" —  t'   log.  0,602060 
(' —  t   log.co.ar.9,397940 

M    log.  9,940795 


To  find    r2  (3i). 


Ri 

i,oi453 

log. 

—  2R 

log. 

©-a 

cos. 

coeff.  of  p 

=—0,28854  log. 

9 

sec. 

scc2.9= 

=i,io3S4 

log. 

To  find 

j-rtz> 

Rii-2  1,01011 

log. 

—2R" 

log. 

©"—a" 

cos. 

M 

log. 

coeffi.of  |)= 

=— I,2l47 

I  log. 

6" 

sec. 

M 

log- 

M.sec.6" 

log. 

Jia.sec2  a 

"=0,9085 

2  log. 

0,006264 

o,3o4i62, 
9,i56o45 

9,46o207„ 

0,02l452 

0,042904 


(32). 

o, 004368 

o,3o32i4, 
9,84o464 
9,940795 

o,o84473„ 

o,o3837i 
9,940795 

9,979166 
9,958332 


vieO) 
(181) 


To  find    c2     (33). 


—2R 

R" 

log- 
log, 
cos. 

o,3o4i62„ 

0,002184 

9.995976 

—  2,00596 

log- 
log. 

COS. 

0,302322„ 

272" 

o,3o32i4 

7,892666 

i^'  term^o,0i57o 

8,195880 

2R    . 

log. 
CO;, 
log. 

o,3o4i62 

9,894275 
9,940795 

2"''term=i,37795 

log- 

los;. 
log. 

COS. 

0,139232 

coefr.  of f=i, 39365 

— 2 

M 

a"— a 

o,3oio3o„ 

9.940795 

9,861378 

i-''term=— 1,26825 

log- 
log, 
tang 
tang 

o,io32o3„ 

— 2  . 

M  . 

S  . 
9"  . 

o,3oio3o„ 
9.940795 
9.508 1 75„ 
9,643092,, 

2"''term= — 0,2472; 

log. 

9,393092,, 

COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 

Three  Fundamental  Equations. 

7-2  =      1,01453  —  o,28854.f  4-  i,io384  f^  (Ji) 

r"~  =:      1,01011  —  i,2i47i-/i -(- o,go852.f2  (JJ) 

Sum        r2 ^  >-"2  =      2,02404  —  i,5o335./i  -j-2,oi236f2  (/)) 
Add  the  other  terms  of    c-,     — 2,oo5g6  +  i,39365.f  —  I,5i548.f3 

Sum  is     c2  =      0,01868  —  0,10960./!  +  0,49688.^  (C) 

Coinpuliition  of    f    from  the  equations  (.?),(£),  (C). 


805 

[591)4] 

(182) 
(183) 
(18-1) 
(185) 
(186) 


Col.  1. 

Col.  2.  1  Col.  3.  1    Col.  4. 

Col.  5. 

Col.  6. 

Assumed  Viilues 

of     J. 

Corresponding   terms  of  the 
equations     {A),  (B),  (C). 

Values  of 
>■,       >■",       c. 

T 

r-2       j      r"2      1       c9 

Hypothesis  I. 

f  =  1,0 

as  in  (i4i). 

i,oi4 

—,288 

i,io3 

1,010 

-I,2l4 

0,908 

0,018 

— 0,109 

o,4g6 

r=  1,35 
r"  =  0,84 

3.^doys 

r-{-'"=  2,19 

1,829 

0,704 

o,4o5 

c  =  0,64 

Hypothesis  11. 

t=J=o,33333 

1,01453 

—,09618 

,12265 

1,0101 1 

—,40490 

,10095 

0,01868 

—  ,o3653 

,o552i 

r  =  1,0202g 
r"=o,84o33 

r+r"=  1,86062 

7,53g 

1 

,i3o 

i,o4ioo 

0,70616 

o,o3736 

c  =  0,19339 

7,660 

Hypothesis  HI. 

Add    1    or 

0,01667     makes 

f  =  0,35 

1 ,01453 
— ,ioogg 

,13522 

1,01011 

-,425i4 

0,11129 

0,01868 

—  ,o3836 

,06087 

r  =  I  ,o24oy 
»■"=  0,83443 

r-\-r"  =  1,85852 

7,903 

18 

,1 17 

1,04876 

0,69626 

0,04119 

c  =  0,20395 

8,o38 

Hypothesis  IV. 

Less     j;     or 
0,00175     makes 

f  =  0,34825 

i,oi453 

— ,10048 

,13387 

1,01011 

— ,423oa 

,11018 

0,01868 

—  ,o38i6 

,06025 

r  =  1 ,02368 
r"  =  o,835o3 

7,9^3 
18 

7,99'"' 

r  4- r"=  1,85871 

1 ,04792 

0,69727 

0,04077 

c  =  0,20191 

Hypothesis  V. 

Add  o,ooo4-/>    or 

0,000 1 4     makes 

f  =  0,34839 

1,01453 
— ,ioo52 

,13398 

1,01011 

-o,423i9 

0,11027 

0,01868 

—  ,o38i8 

,060  3 1 

r  =  1,02372 
r"  =  o,834g9 

r  +  r"=  1,85871 

7,903 
18 

79 

1,04799 

0,69719 

o,o4o8 1 

c  =  0,20201 

8,000 

Col.  7.    Col.  8.     Col.  9.    Col.  10. 


Coefficients  of 


i 

I 
JiJ 

2ffcr 

,ooo4 


0,38854 


O,og6i8o 
48og 


o,ioog8g 
— 5o4 


o,4o4go3  o,o36533 
20245|    1826 


o,  100435 
4o 


1,21471  o,iog6o 


o,425i48'o,o38359 

3135!         191 


o,423o23^o,o38i68 
169I  1 5 


0,1005250,423193  o.o3Si83 


Coefficients  of 


f- 


1  0 
1 


1  uo 


+1 


,0008 


i,io384  |0,go852 


0,1226490,100947 

1 3365!   lOogS 

306;     3  52 


o,i3522o  0,1  I13g4 

— i352  — iii3 

3      3 


o,i3387i  0,110184 

107  88 


0,1 33978  0,1 10372 


o,4g688 


o,o552o8 
552 
i38 


0,060867 
—609 


0,060259 
48 


o,o6o3o7 


With  these  last  found  values  of  f  =  0,34839,  r=  1,02372,  r"  =  0,83499,  we  shall  now  compute  the 
elements  of  the  orbit,  by  means  of  the  formulas  (34—45)  ;  observing,  that  as  r  >  r",  the  comet  must  be 
nearer  the  perihelion  at  the  third  observation  than  at  the  first. 


(187) 


(188 


(189) 


(ISO) 


(191) 


1,152) 


Computation  of  the  elements  of  the  orbit. 
f  =  0,34839        log.         9,542066 
M  log.         9,940795 

t"  —   1/  ' 


log.  9,482861 
j"  0,83499  '"§•  <^o-  ,078319 
6"  tang.      9,643o92„ 


•IS-"  =  —      cf  1 2™  37' 


9,304a72n 


/>  log.  9,543066 

r        1,02372         log.  CO.  g.gSgSig 

6  tang.  9,5ù8i75„ 

«^  =  —  6<'i7m45'        sin.  g,o4oo6o„ 


VOL.   III. 


202 


©-a 


see.  0,002627 

log.  CO.  9,g8g8i9 

log.  9,542066 

sin.  9,995499 


i=    19"  48'»  35»        sin.        9,53ooii 
A  =  342''  42°'  o5'  =  ©  -I-  iS'S^         " 

/3  =      2''  So"»  3o»  =  .4  -f  6 
/3"  =      S"*  55'"  06'      found  in  (196) 


yS"  —  ^  =      id  24"  36» 

w  =      -;''  II'"  35'       found  in  (197) 

/S"  —  tJ  =    10''  36'"  oi'  =  y5"  —  ;S  -|-  to 
U  =  355"*  igtn  o5'  =  /3  —  u> 


(193) 


(m) 


(195) 


806 

[5994] 


APPENDIX,  BY  THE  TRANSLATOR; 


(196) 


(197) 


(197') 


(198) 


■  a" 


sec.  o,oo5636 

log.  CO.  0,078319 

log.  9,482861 

sin.  9,858147 


('/ =     i5''25"'46'        sin.        9,424963 
All  =  SSo"*  29""  20»  =  ©"  -Jf-  180^ 

;5"  =      S"*  55"<  06'  =  Jill  +  s" 

—  ^  =      3ii  24™  36»        cosec.     1,225625 

OT-  cot.  0,957317» 

V  tang.       9,209914» 


24,7090        '°g- 
-cot.(/5"  — ^)  —  16,7824 


1,392856 


cot.jc  =    7,9366        log.        0,899087 

u)  =      7'*  II'"  25"        cosec.     0,902518 
OT  tang.      9,042683,1 


Inclination  f  =  — 41'' 23™  4i'        tang.      9,g4520i„ 

-  «"  =  '35"  54"'  oo»  >  f^^^j  i„  „^^  ^d  ,„,„^„ 
m"  =    i4<'  00"'  29»  ) 

Perihel.  —  u=  i49''54"'  29» 

Long,  u  =  355''  19™  o5*'    found  '"  ('95) 

Long.  Perih.  =  i45''  i3"'  34»     on  the  orbit. 

Time  of 


OT  COS.         9,997373 

w  COS.         9,996571 

u=      9*32"' 46»        COS.         9,993944 


COS.         9,994364 
COS.         9,992525 

COS.         9,986889 


(193)    /3"_u 

«"  =    14*^  oowi  29» 
^  =  u"  —  u=     ifi  27"'  43« 


4;(^  :=     2<f  i3'»  52»        cosec.     1,409711 


è  log-r 

arith. 

co.9,9g49og 

è  log.r" 

g.960840 

Number               23,ig85 

log. 

i,36546o 

—  cot.J;^^  ^  —  25,6674 

tang.4i)"  =  —    2,4689 

\v'i  =  —    67''  57'"  00 

COS. 

9,574512 

same 

COS. 

9,5745 1 2 

)-" 

log. 

9,921681 

log. 


Per.  Dist.     B=        0,11768 
half 
t)"  =  —  135''  54*"  00»  tab.  Ill  log.     2,789133 

Time  from  Per.        24'''»»,8422 

Third  obs.  Sept.      1 2""»», 5833 

Perihelion,  October    7''''!;%4255. 


log. 


9,070705 
9,535352 


i.BgSigo 


(198') 
(199) 

(200) 

(201) 
(302) 
(203) 

(204) 
(205) 

(206) 


The   value  of    v"    being  negative,  indicates,  that  the  comet  was   approaching  towards 
the  perihelion  at  the  time  of  the  third  observation.     The  heliocentric  latitudes, 

«  =  _C''17'"45';  tn"  =— 9"12'"37% 

being  south  and  increasing,  it  is  evident,  that  the  comet  had  passed  the  descending  node  ?3, 
a  short  time  before  the  first  observation  ;  and  we  have  therefore  calculated  the  longitude 
of  that  node  355'' 19'"  05"-,  to  which  corresponds  9=:  —  41''23"'41',  which  is  the 
same  as  to  put  ^  =  175'' 19"'05',  and  <?  =  41''23'"4I''.  Hence  the  approximate 
elements  of  the  orbit  are, 

Longitude  of  the  ascending  node  175''  19'"  05'; 

Inclination  41"  23-"  41' 

Longitude  of  the  Perihelion  145"13'"34' 

Perihelion  distance  0,11768 

Time  of  passing  the  Perihelion  1769,  Oct.     7''''J'%4255. 

To  illustrate  the  process  of  finding  P,  r,  r",  from  the  fundamental  equations  (31,32,33), 
we  shall  give  the  following  additional  examples. 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


EXAMPLE    II. 

Thd  equations   in   lliis  cxnmple,  correspond  to   those  of  the   comet   of   i8o5,  as  given   by   Mr   Ivory   in    the 
Transactions  of  the  Royal  Society  for  i8i4,  page  170. 

r2  =  0,973662  -[-  1,408969.^  -\-  i.oooooo.f'î  ;  (.1) 

r"2  =  0,969967  -(-  o,23oo47.f  -)-  o,i3i45o.f2  ;  (g) 

c2  =  o,o435o5  +  o,ii52oo.f  +  o,5i8768./i9  ;  (C) 

ra  _[-  r"-2  =  1,943629  -\-  i,6390i6.f  -f-  i,i3i45o.f3.  (iJ) 

Interval  between  the  extreme  observations     T  =:   H'>"y<^,f)j34. 


Col.  1. 

Col.  2.  Col.  3.  1  Col.  4. 

Col.  5. 

Col.  ti. 

f 

r2   1  r"a 

c2 

r,     r",     c 

T 

Hypothesis  1. 

f  =  §  or  0,16667 
as  in  (146). 

0,97366  0,96997 

,23483    3834 

2778    365 

0,043  5o5 
19200 
i44io 

r=  1,11188 
r"  =  1,00596 

r-\-r"=  2,11784 

c  —  0,27769 

ii,3g2 

21 

,324 

1,23627  1,01196 

0,077115 

11,73- 

ii,84i 
i5 
87 

Hypothesis  II. 

Add  5Ô  or  o,oo833 
f  =  0,175 

0,97366  0,96997 

,24657   4026 

3062    402 

o,o435o5 
20160 
15887 

r=  i,ii84i 

r"  =  1 ,007 1 0 

r+r"  =  2, i255i 

i,25o85  i,oi425 

0,079552 

c  =  0,28205 

1 1 ,943 

Hypothesis  III. 

Add  IÏÛ  =  0,00125 
f  =  0,17625 

0,97366  0,96997 

,24833.   4o55 

3io61    408 

1 

o,o435o5 
2o3o4 
i6ii5 

r  =  1,1193g 
r"  =  1,00727 

n,84i 

19 

,ii4 

r4-»-"  =  2,12666 

i,253o5|  i,oi46o 

o,07gg34 

c  =  0,28271 

1 1 .974 

Col.  7.|  Col.  8.  1  Col.  9.  Col.  10. 

Coefficients  of  f. 

X 

1 
150 

1,408969 

o,23oo47 

0,11  5200 

0,234828 
I1741 

o,o3834i 
1917 

0,019200 
960 

o,24656g 
1761 

o,o4o258 
288 

0,020160 
1 44 

n.24833i 

L.,o4o546 

o.o?o3o4 

Coefficients  of  /i'2.      1 

1 

6 
1 

==1 

1 

280 

1 ,000000 

o,i3i45o 

0,518768 

0,166667 

0,02 1  go8 

o,o8646i 

0,027778 

2778 

69 

o,oo365i 

365 

9 

o,or44io 

144 1 

36 

o,o3o62  5 

437 

2 

o,oo4o25 
57 

0,015887 
227 

o,o3 1 064 

0,004082 

o,oi6ii5 

807 

[5994] 


(207) 
(208) 
(209) 
(210) 

(211) 


Henco  f^  0,17625,     r^i,iig3g, 

Mr  Ivory  makes,     /i  =.0,17620,    r  =  1,11936, 


r    =  1,00727. 
r"  =  1,00727. 


(212) 


(213) 


(214) 


(215) 


EXAMPLE    III. 

These  equations  are   similar  to  those  given  by  Mr  Ivory  in  the  Transactions  of  the   Royal   Society  for    i8i4, 
page  160  ;  and  correspond  to  the  comet  of  1781.. 

r2  =  0,976625  —  o,3o3724.f  +  i.oooooo.fa  ;  (jÎ) 

r"2=  0,972873  —  i,457243.f  -\-  3,788i66.f2  ;  (S) 

£2  =  0,080278  —  0,353719.,  +  i,2378i8.,2  ;  (  C) 

r-2  -j-  r"3  =  i,94g4g8  —  1,760967-,  +  4,7881 66., 3.  (D) 

Interval  between  the  extreme  observations     T"  =  10  °''. 


(216) 
(217) 
(2!8) 
(219) 

(220) 


808 

[5994] 


APPENDIX,  BY  THE  TRANSLATOR; 


(221) 


(222) 


(223) 


(234) 


(235) 


Col.  I. 

Col.  2. 

Col.  3. 

Col.  4. 

Col.  5. 

Col.  6. 

f 

/■2 

r"2 

cS 

r,     t",     c 

T 

Hypothesis  1. 

P  =  o,33333 
as  in  (i47). 

0,97663 

— ,10124 

,11111 

0.97287 

-,48575 

,42091 

0,030278 

— ,1 17906 

,137535 

r  =  0,99323 
r"  =  0,95291 

8,902 

14 

1 37 

r-\-r"  =  1,94614 

0,98650 

0,90803 

0,049907 

c  =  0,2234 

9,o53 

Hypothesis  H. 
Add  50  malces 
f  =0,35 

0,97663 
— ,io63o 

,1225o 

0,97287 

— ,5ioo3 

,464o5 

0,030278 

— ,i238oi 

,i5i633 

r  =  0, 99640 
?■''  =  0,96275 

9,735 

23 

43 

r-j-  r"  =  i,95gi5 

0,99283 

0,92689 

o,o58tio 

c  =  0,24106 

9,801 

Hypothesis   HI. 

.Add  100  malies 

f  =  0,3535 

0,97663 

—  .10737 

,  1 2496 

0,97287 

— ,5i5i3 

,47338 

0,030278 

— ,i25o3g 

,  1 54681 

r  =  0,99711 

r"  =  0,96494 

9,760 
195 

r  4-  r"  =  1 ,96205 

0,99422 

0,93113 

0,059920 

c  =  0,24479 

9,960 

Hypothesis  IV. 

.Add  500  or  o,ooo88 

f  =  0,35438 

0,97663 

— ,10763 

,.2559 

0,97287 

—  5 1642 

■47575 

0,030278 

—,125352 

,155455 

r  =  o,9973o 
r"  =  0,96550 

9,760 
233 

r  -(-  !■''  ^  1 ,96280 

0,99459 

0,93220 

o,o6o38i 

c  =  0,24573 

10,000 

Col.  7.    Col.  S.       Col.  9.  1  Col.  10. 

Coefficients  of    f  . 

h 

1 
55 

I 
lou 

1 
4110 

o,3o3724 

1,457243 

0,35371g 

0,101241 
5062 

o,io63o3 
io63 

o,48574S 
24287 

0,117906 
5895 

o,5ioo35 
5 1 00 

0,i238ûi 
1238 

0,107366 
268 

o,5i5i35 
128S 

o,i25o39 
3i3 

0,107634 

n.5i64.,3 

o,i25352 

Coefficients  of    ^2.               | 

1 

I 

10 
J 

1,0000003,788166 

1,237818 

0,11111  1 
11  III 

278 

0,420907 
42091 

1052 

0,137535 

13754 

344 

1 
ill 

1 
sou 

1 

SfJO 
8ÙU 

0,122500 

2450 

12 

o,464o5o 

9281 

46 

o,i5i633 

3o33 

i5 

0,124962 
625 

1 

0,473377 

2367 

3 

0,1 54681 

773 

I 

o.i25588'o,475747 

0,T  55455 

(226) 
(227) 
(228) 
(229) 
(230) 


(231) 


(232) 


(233) 


(234) 


Hence     ;i  =  o, 35438,    r  =  0,99730,     r"  =  0,96530  ;     which  agree    with  Mr  Ivory's  calculation,  excepting 
a  unit  in  the  last  decimal  place. 

EXAMPLE     IV. 

These  equations  are  equivalent  to  those  given  by  Mr  Ivory,  in   the  Transactions   of  the    Royal    Society    for 
i8i4,  page  i65  ;  and  refer  to  the  comet  of  176g. 

r2  =  T ,017347  —  0,778609.^1  -(-  I,O00O0O./l2  ;  (^) 

r"~  =  1,010107  —  1,297813.^ -|-  1,033677.^2  ;         (£') 

c3  =0,004678  — o,0275i8.f -l-o,i396i9.()2  ;         (C) 

j-2  _|_  r"2  =  2,022454  —  2,076422.^  -1-  2,o33677.f2.  (JD) 

Interval  between  the  extreme  observations     T"  =  4  "^'^ 


f 

r2 

r"-2 

t2 

r,     r'l,    c 

T 

Hypothesis  I. 

f  =  i  =  0'25 
as  in  (i48). 

1,012 

—,194 

62 

1,010 

-,324 

64 

o,oo46 
—,0068 

87 

r  =  0,94 
r"  =  0,86 

3,119 

r  +  r"=  1,80 

0,880 

o,75o 

o,oo65 

C  =:  0,080 

Hypothesis  II. 
p  =  J  =  0,33333 

1,01235 

-25954 

,11111 

1 ,0 1 0 II 

—,43260 

,11485 

0,004678 

—     9'73 

i55i3 

r  =  0,92947 
r"  =  o,832og 

3,856 

3 

,191 

/•  +  )■"=  1,761 56 

0,86392 

0,69236 

0,011018 

c  =  0, 10497 

4,049 

Hypothesis  III. 

Sub.  j'o  or  o,oo4i7 

p  =  0,32916 

1,01235 

—,25629 

,io835 

1,01011 

—,42720 

,11200 

0,004678 

—      9o58 

i5i27 

r  =  0,92974 
r"  =  0,83362 

3,856 

3 

,i4i 

r  4- r"=  1,76336 

o,8644i 

0,69491 

0,010747 

c  =  0,10367 

4,000 

Coefficients  of    f.               1 

i 

0,778609 

1,297813 

0,027518 

0,194 

0,324 

0,0068 

I 

0,259536 
—   3244 

0,432604 
—   5408 

0,009178 
—      ii5 

10,256292 

0,427196 

0,009058 

Coefficients  of    f-.              i 

1 

15 

1 ,000000 

1,033677 

0,13961g 

0,062 

0,064 

0,0087 

5 

1 

0,1  11111 

—     2778 
17 

o,ii4853 

—    2871 

18 

o,oi55i3 

—      388 

2 

o,io835o 

0.1  120no 

o,ni5l27 

Hence 

The  true  values  being 


(5  =  0,32916,     r  =  0,92974,     »•"  =  0,83362. 
f;— 0,32911,    r  ^  0,92974,    r"=o,8336i. 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


EXAMPLE     V. 


809 

[5994] 


The  foUouins  equations  were  comi)utcil  liy  Dr  Olliers   in  liis  Abhandlung,  &c.,  page  Sg  ;  they  correspond  to 
the  comet  of  i6Si,  and  were  computed  from  Halley'^  elements,  and  not  deduced  from  actual  observations. 

r2  =  0,96734  —  0,59992  f,  4-  i,24328./>3  (.;?) 

r"3  =  0,96941  —  o,4oi85.f  -f  2,2oo87,f3  (B) 

c2  =  0,019726—0,122756.^-1-0,265982.^2  (C) 

rS  +  i-"a  =  1,93695  -  o,gg477./>+3,444i5.f2  (D) 

Interval  between  the  extreme  observations     T  =  8''^''*,o47. 


Col.  1. 

Col.  2.     Col.  3.  1 

Col.  4. 

Col.  5. 

Col.  G 
T 

P 

r-2 

,-"2 

c3 

r,    »■",    c 

Hypothesis  I. 

f  =  0,5 
as  in  (i49)- 

0,96754   0,96941 

— ,2g646 — ,20092 

,31082      ,55022 

,oig726 

—,061378 

,066495 

r  =  0,99091 
r'' =  1,1 4835 

J--|-r"  =  2,i3g26 

6,363 

1 4 

,32  3 

6,699 

OjgSigo 

1,31871 

,024843 

c  =  0,15763 

Hypothesis  11. 
Add  15  or  ,o5 

p  :=  0,55 

o,g6754 

— ,32611 

,3760g 

0,96941 

— ,22102 

,66576 

,019726 

— ,067516 

,080459 

r  =  1,00872 
r"=  1,18918 

7;74o 
i4 

33 

r  +  r"=  2,19790 

1,01752 

i,4i4i5 

,o3s669 

c  ^=  0,18074 

7,786 

Hypothesis  III. 

Add  50  or  0,01 1 
f  =  o,56i 

o,g6754 

—,33263 

,39129 

0,96941 

—,22544 

,69266 

,019726 

—,068866 

,083709 

r  =  i,oi3o2 
r"=  i,ig85g 

7,776 

3 

,256 

r-t^r"  =  2,21161 

1 ,02620 

1,43663 

,034569 

c  =  0,18593 

8,o35 

Hypothesis  IV. 

Add  1  =o,ooo56i 

lUUO 

f  =  o,56i56i 

0,9675/ 

-,33296 

,39207 

0,96941 

—,22566 

,69404 

,019726 

— ,o6Sg35 

,083876 

r  =  I, 01 324 
r"  =  1,19908 

7,776 

4 

,267 

r-\-ir"  =  2,21332 

1, 02665 

1^43779 

,034667 

e  ^0,18619 

8,047 

Col.  7. 

Col.  S. 

Col.  9.     Col.  lO.J 

CoelTicients  of    p.               i 

t 
tV 

r 

o,5g2g2    o,4oi85 

0,122756 

0,296460 
3g646 

o,20og25 
20093 

0,061378 
6i38 

0,326106 

6522 

0,221017 
4420 

0,067516 
i35o 

0,332628 
33? 

0,225437 
225 

0,068866 
69 

0,332960 

0,2  2  5663 

0,068935 

Coefficients  of    fi.            1 

TDWcT 

r,34,J28 

3,20087 

0,265982 

o,3io82o 

62164 

3io8 

0,550217 

',110043 

55o2 

o,o664g5 

1329g 

665 

0,376093 

i5o44 

i5o 

0,665762 

2663 1 

266 

o,o8o45g 
3218 

32 

o,3gi386 
782 

o,6g2659 
i385 

0,08370g 
167 

o,3g2o68 

o,694o44iO,o83876| 

(235) 
(236) 


(237) 


Hence    f  =  o,56i56i,    r=i,oi334,    r"=i,ig9o8.     The  actual  values,  according  to  Halley's  theory,  upon      ,333 
which  the  proposed  equations  are  founded,  are  t  =  i,oi44,    r"  =  1,2000  ;    which  agree,  very  nearly,  with  the 
preceding  result. 

EXAMPLE    VI. 

These  equations  correspond  to  the  comet  of  i8o5,  in  the  calculation  of  Mr.  Ivory  in   the  Transactions   of  the 
Royal  Society  for  i8i4,  page  175. 

r2  =  o,988ig2  —  1,271721.^-1-1  ,oooooo.f 2  ; 
t"-2  =  o,g8ig87  —  2,3ii644.f  -f-  i,88i447f'-  ; 
e2  =  0,043371  —  o,07448g./>  -|-  o,485838  p9  ;  (239) 

r2  -\-  r"2  =  1,970179  —  3,583365.f  -f-  2,88i447-f2.  (3«) 

Interval  between  the  extreme  observations     7"=  12  *^',o36. 


VOL.  III. 


203 


810 


APPENDIX,  BY  THE  TRANSLATOR; 


[5994] 


CS-40 


Col  .1. 

Col.  2. 

Col.  3. 

Col.  4. 

Col  5. 

Col.  6. 

f 

,a 

r"i 

ca 

r  ,    r",     c 

T 

Hypothesis  I. 

f=  I 
as  in  (240- 

0,98 

—  1,27 
-j-i,oo 

0,98 

— 2,3l 

-1-1,88 

o,o43 

—,074 
+.485 

r  =  0,84 
r"  =  0,74 

r-\-r"  =1 ,58 
c  =  0,67 

24days 

0,71 

0.55 

0,454 

Hypothesis  II. 
f  =  è 

0,98819 
—,63586 

,25oOO 

0,98199 

-i,i5582 

,47o36 

0,043371 

-   37244 

,121459 

r  =  0,77610 
r"  =  0,54455 

11,653 

3 

,238 

r-i-r"=  i,32o65 

0,60233 

0,29653 

0,127586 

f,  =  0,35719 

11,894 

Hypothesis  HI. 

Add  jij  or  o,o5 

f  =  o,5o5 

0,9881g 
—,64222 

,25502 

0,98199 

-1,16738 

,47982 

0,043371 

—   37616 

,i23goo 

r  =  0,77523 
r"  =  0,54263 

1 1 ,938 

36 
3 

r  +  r"=  i,3i785 
c  =  0, 36008 

0,60099 

0,29443 

0,129655 

1 1  >977 

Hypothesis  IV. 
Add  jijj  or,o  o33 

p  =  o,5o83 

0,98819 

— ,6465o 

,25844 

0,98199 

-I, 17516 

,48623 

0,043371 

—   37867 

,125557 

r  =  0,77468 
r"  =  o,54i35 

11,938 
28 
67 

r-f->-"  =  i,3i6o3 

o,6ooi3 

0,29306 

o,i3io6i 

c  =  0,36202 

i2,o33 

11,938 
28 

70 

Hypothesis  V. 

Add  5^0  =  o,ooi7 

f  =  o,5o847 

0,98819 

— ,64673 

,2586i 

0,98199 

-1,17555 

,48656 

0,043371 

—   37880 

,12  5641 

r  =  o,77465 
r"  =  0,54129 

r-\-r"=  i,3i594 

0,60008 

0,29300 

o,i3ii32 

c  =  0,36212 

1 2  ,o36 

Col.  7. 

Col.  8.    Col.  9.    Col.  10.1 

Coefficients  of    p.               1 

è 

I 

I,27i73i|2.3i  16440,074489 

o,63586o  1,1558220,037244 
6359       ii558|          372 

1 

0,642219 
4281 

1,1673800,037616 

7783|          35i 

1 

(i,6465oo  1,1751630,037867 
3i5j          3g2             i3 

o.6407i5!i, 1755550,037880 

Coefficients  of    f  2                1 

i 

s'ô 
1 

200 

2 
ISO 

ah 

T5ÛÔ 

1 ,000(100 

1,881447  o,485838| 

O,2  5o000 

5ooo 

25 

0,470362 

9407 

47 

0,121459 

2429 

12 

o,255o25 

3400 

II 

0,479816 

6398 

21 

o,i23goo 

i652 

5 

o,258436 

172 

0,486235  o,i25557J 
324             84| 

0, 258608  •0.486559  0,1 2  aUi  j 

(242)    Hence 

Mr  Ivory  makes 


f  =  o,5o847,    r  =  0,77465,    r"  =  0,54129. 
f  =  o,5o8i,      r  =:  0,77472,    r'' ==  o,54I44• 


(242') 


From  these  examples  we  see  that  the  interval  of  time  T,  between  the  extreme 
observations,  is  found  in  Table  II,  with  a  sufficient  degree  of  accuracy,  and  that  the  results 
agree  with  the  calculations  by  logarithms  of  other  astronomers,  although  the  table  is  only 
carried  to  the  nearest  unit  in  the  third  decimal  place.  While  treating  upon  this  subject,  it 
may  not  be  amiss  to  recall  to  mind  the  remarks  of  La  Lande,  in  the  third  volume,  page  259, 

of  the  third  edition  of  his  astronomy,  relative 
to  the  degree  of  accuracy  in  the  cometary 
calculations.  He  has  there  given  a  table 
of  the  elements  of  the  orbits  of  those  comets 
which  had  been  previously  computed, 
giving  the  longitudes  and  angles  to  seconds, 
and  thelogarithmsof  the  perihelion  distances 
to  five  or  six  decimals  ;  but  at  the  same  time 
observing,  that  though  he  has  inserted  the 
seconds,  no  confidence  could  be  placed  in 
them;  neither  could  we  depend  on  the 
correctness    of   the     logarithms    of    the 


Col.  1. 

Col.  2. 

Col.  3. 

Col.  4. 

Examples. 

Time     T   by 

Observation. 

Time     T   by 
Table  JI. 

Errors. 

I. 

8''''y%ooo 

8'"'y',o2o 

-f  o''^y%020 

II. 

I.''^^^973 

ii'"'^",98i 

-(-  o'''■'>•^oo8 

HI. 

days 
10     ■'   ,000 

9''''^^998 

-  0''">'^002 

-  o"='^-',ooi 

IV. 

4'""",ooo 

3"^^^999 

V. 

s-^'^'Mi 

8"'=>'^o6o 

+  o'"'^",oi3 

VI. 

i2'^''",o36 

days 
12        ,129 

+  o'^''^^093 

COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  811 

[5994] 
perihelion  distances  in  the  fourth  decimal  place,  as  is  abundantly  manifest,  by  comparing  the 

results  of  the  calculations  of  différent  astronomers.     To  estimate  the  degree  of  accuracy  with 

which  the  time   T  can  be  ascertained,  by  entering  Table  II,  with  the  values  of  r~^r"^  at  the 

bottom  of  the  table  and    c^    at  the  right  hand  side  ;  we  have  computed  the  value  of    T,    for    (243., 

the  six  preceding  examples;  as  in  the  third  column  of  the  annexed  table;  the  times  by 

observation  being  given  in  the  second  column,  and  their  differences  or  errors  respectively,  in 

the   fourth    column.     These    errors  being  very    small,    it  is  evident,  that   the    method    of 

combining  the  equations  (C),  (Dj,  or  the  values  of    r-  -f-  r"^,  c^  ;     by  means  of  Table  II, 

must  generally  give  a  very  close  approximation  to  the  value  of    p. 


Gauss  varied  the  forms  of  the  equations  (31,32,33),  by  the  introduction  of  several 
auxiliary  numbers  A,  B,  B'  b,  b",  c,  c",  he.  which  are  deduced  from  the  co-efficients  of 
the  terms  in  the  original  equations  ;  changing  also  the  unknown  quantity  p  into  u  ;  so 
as  to  reduce  the  expression  of  c^  (33),  to  the  form  in  (244).  The  object  of  these 
transformations  is  to  render  the  calculations  more  convenient  for  computation  by  logarithms, 
by  putting  them  under  the  following  forms; 


(243) 


(244) 


When  the  equations  are   given  in  this  form,  we  may  determine  u,  by  means  of  Tables  I,  II, 
or  by  successive  apjiroximations,  in  the  same  manner  as  we  have  found    p     in  the  preceding 
examples  ;  using  in  Table  II  the  arguments,     r  -f-  r"     at  the   top,  with  c  at  the  side  ;  and 
it  is  evident,  on  account  of  the  decrease  of  the  number  of  terms  in   the  expression  of    c^ 
(244),  that  the   calculation  of  u  is  more  simple  than   that   of  finding     p     in  the   former    (S") 
examjiles  ;  but  the  ?aving  of  labor  is  nowise  sufficient  for  the  trouble  of  reducing  the  equations 
to  the  forms  (244),  when  the  time  is  deduced  from  Table  II,  in  the  manner  we  have  here 
pointed  out.     We  may  also  use  the  equations  (C),  (D),  or  the    values  of    r^  -j-  r''^     and 
c^,    in  finding  the  first  rough  estimate  of  u  ;  in  like  manner  as  we  have  proceeded  with  the 
similar  expressions  in    terms  of    p    in    (136 — 150).     This   process    may    be  illustrated, 
by  the  two  following  examples.     Thus  if  we  put     ?«  =  0,    in  (248,247),  we  shall  have 
r= -|- /'^  =  2,49,  c- =0,028,     whence  we  obtain,  by  inspection  in  Table  II,     T^7''*>'^3     (2«') 
nearly  ;  which  is  less    than  the  time  by    observation    14''^>%0493.     We  also  observe  by 
inspecting  the   same  vertical  column,  corresponding  to     r^  -f-  r"^  =  2,49  :     that  this  last 
mentioned  time  corresponds  very  nearly  in  the  margin  to     c-  =  0,11  ;     substituting  this 
in  (247)  we  get    0,11  =:  0,028  -f-  u^,     whence  we  obtain     7i  =  0,28,  or  nearly  1/  =  |,     (2«) 
which   is   assumed   in   (249).     In   like   manner,  in  Example    VIII,  we   have,  by   putting 
„  =  0,    in  (2.54,2.53)     r^  +  r"^  ^  12,53,  c^  =  0,051  ;     which  correspond  in  Table  II, 
to  14'^^''', S .     If  we  suppose  7L  =  3-V,  we  get  r- -f  ?-"2  =  23,2,  c^  =  0,062  ;    corresponding 
in  Table  II  to    18''"5'%9.     As  the  actual  time  by  observation  falls   nearly  midway  between 

■'  ■'  (246) 

these  two  times,  we  may  assume,  for  an  approximate  value,  t<-  =  rrj,     as  in  (255). 


812 

[5994] 


(247) 

(248) 


APPENDIX,  BY  THE  TRANSLATOR  ; 

EXAMPLE   VII. 

The  following  equations  correspond  to  the  second  comet   of  i8i3.     They   are    equivalent  to   those   given  by 
Gauss  ill  vol.  28,  page  Sog,  of   the  Monatliche  Correspondenz  ;  or  by  Encke,  in  the  Jahrbuch,  for  i833,  page  284. 

r2  =  1,2441 5  -\-  i,92565.u  -{-  ZfiGgjS.u^  ;        (Jl) 

j-"a  =  1,24837  4-  i,5i429.M  -+-  o,-jg33i.u^  ;        (£) 

c2  =0,028219-]- «3;  (O 

ra  -\-  r"-2  =  2,49252  -f-  3,43994.m  +  3,863o4.w2  ;        (D) 

Interval  between  the  extreme  oliservations     T  =  i4  ^^',o493. 


(249) 


Col.  7.    Col.  S.       Col.  9.   |Col.  10. 

Coelficients  of    u . 

i 

65 

1 

1 

4000 

1,92565  |i, 51429 

o,48i4i2  0,378572 
— 9628    — 7571 

0,4717840,371001 
— 2358|  — i855 

0,4694260,369146 
117',           93 

0.469543  0,369238 

Coefficients  of    u^.             1 

i 

1 
100 

2 

200 

1 

400 
3 

40ÔÔ 

3,06973  ]o,7933i 

1 ,00000 

,7674320,198328 

,25oooo 

,191858 

-7674 
77 

0,049582 

—1983 

20 

0,062500 
— 25oo 

25 

0,184261 

—  1843 

5 

0,047619 

—476 

I 

0,060025 
— 600 

I 

O,i82423|o,o47i44 
91            24 

0,059426 
3o 

o,i835j4  0.04-168  0,059456] 

Hence  we  have  «  =  o,243836,        r  =  1,37702,        r"  =  1,29026  ; 

According  to  Gauss,  u  =  0,24388,  r  =  1,37708,         r"  =  1,29027  ; 

(250)  According  to  Encke,  r  =  1,37705,         r"=  1,29027. 

We  may  observe,  that  the  last,  or  fourth  hypothesis,  may  be   dispensed   with,  by  interpolating  between   the 
values  of    f,  r,  r",    given  in  the  second  and  third  hypothesis,  so  as  to  make     T    correspond   to  the   proposed 

interval    1 4''°^'',o493. 


(251) 
(252) 
(253) 
(254) 


EXAMPLE    VIII. 

The  following  equations  correspond  to  the  comet  of  1825,  calculated  by  Nicolai  in  the  tenth  volume   of  the 
Jlstronomische  JVachrichten,  page  238. 

r2  =  6,2o536  -\-  43,23445.M  -{-   8o,07556.m2  ;  (^) 

r"2  =  6,332i3-f-46,4i4ii.M+   93,5o6io.«2;  (B) 

c2  =  o,o5i58-|-«2;  (C) 

r2  _^  r"a  =  12,53749  +  89,64856.u  +  i73,58i66.m2  (Z>) 

Interval  between  the  extreme  observations    T  =  i6iiay3,782i. 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


Col.    1. 

Col.  2. 

Col.  3.   1    Col.  4. 

Col.  5. 

Col.  6. 

u 

r-3 

,"2              c3 

r,    r",     c 

T 

Hypothesis  1. 

u  =  5ij  ^  o,o5 
as  in  (246). 

6,2o536 

2,16173 

,20019 

6,332x3   o,o5i58 
2,32071 
,23376!      ,0025o 

r  =  2,927 
r"  =  3,g8i 

16,237 

II 

,180 

/■4-r"=  5,908 

8,56727 

8,88660'  o,o54o8 

c  =  0,23355 

16,438 

Hypothesis  II. 
Adil  i  makes 
u  =  o,o58333 

6,3o536 
2,52201 

,2724s 

6,332:3'  o,o5i58 
2,70749 
,3 18 1 7     ,oo34o 

J-  ^  3,0000 
»■"  =  3,0590 

16,374 

83 

,319 

r+r"  =  6,0590 

8.99985 

9,35779   0,05498 

c  =  0,23448 

16,775 

Hypothesis  III. 

Add  ôj,fi  or 
0,0003916  makes 

t(  ^  n,n",869  5 

6,3o536 

2,53462 

,37520 

6,332 1 3   o,o5i58 
2,72103 
,32135          343 

r  =  3,00353 
r"  =  3,061-9 

16,374 
8q 

r-\-r"  =  6,06432 
c  =  0,23454 

,323 

9.ci5i8 

9,3745 1  j  o,o55oi 

16,786 

Col.  7.|   Col.  8.  1   Col.  9. 

Col.  lO.j 

Coellicienls  of    u.              | 

B 

500 

43,23445 

46,4i4ii 

3,16172 
,36029 

2,32071 
38678 

2,52201 
1367 

3,70749 
1 354 

3.534(» 

3,73103 

Coefficients  of    u-.            \ 

I 
400 

1 
IS 

2 

JO(J 

80,07556 

93,50610 

1 ,00000 

0,30019 

667J 
556 

0,33376 

7792 

649 

O,0035o 

83 

7 

0,27248 
272 

o,3i8i7 
3i8 

o,oo34o 

0,27520 

o.33i35 

o,oo343 

813 

[5994J 


1255) 


The  Talue  of  T  by  observation,  falls  between  the  results  of  these  two  last  hypotheses,  and  by  taking 
parts  of  the  corresponding  variations  of  the  values  of  p,  r,  r",  we  get  the  final  values  corresponding  to  the 
actual  value  of    T  ; 

f  =  o,o5852  ;  r  =  3,ooi63  ;  r"  =  3,o6o8o. 


This  manner  of  finding  the  orbit  of  a  comet  has  an  imperfection,  which  obtains  in  several 
other  methods;  namely,  that  it  fails  in  accuracy  in  the  particular  case  where  the  value  of 
M  (30,  or  9-2)  appears  under  the  form  3/  =  g  ;  which  happens  when  the  apparent  j^alh  of 
the  comet  is  in  the  ecliptic,  or  in  any  other  great  circle  passing  through  the  sun.  For  in  this 
case,  as  the  points  A,  B,  C,  figure  85,  page  795,  are  situated  in  the  same  great  circle,  passing 
through  S,  we  shall  have  all  three  of  the  angles  h,  h',  h"  (64),  equal  to  each  other,  and 
then  the  expression  (92)  becomes  M  =  %.  Hence  it  is  evident  that  this  method  can  be 
most  successfully  applied,  in  cases  where  the  arc  B  H,  is  considerable,  in  comparison  with 
the  arc  ..3  C.  When  the  ratio  of  these  arcs,  B  H,  j1  C,  is  small,  there  may  be  instances 
in  which  the  method,  without  actually  failing,  becomes  somewhat  uncertain,  on  account  of 
the  inaccuracy  in  the  estimated  value  o(  M,  in  consequence  of  the  neglected  terms  (93'), 
which  have  a  more  important  influence  than  usual,  and  it  is  an  object  of  interest,  to  obtain 
a  more  correct  estimate  of  the  value  of  M.  We  shall  therefore  proceed  to  investigate  the 
complete  value,  by  the  analytical  methods,  used  by  Gauss,  Ivory,  Encke,  &c.,  without 
neglecting  any  terms,  and  we  shall  obtain  in  (306,  &:c.),  the  correction  to  be  made  to  the 
approximate  value,  which  is  given  in  (30).  Finally  we  shall  give,  in  (355,  &c.),  the  process 
to  be  used  in  the  excepted  case  mentioned  in  (251). 


(256) 

Analytical 
investiga- 
tion   of 
Olbers's 
method. 

(357) 


(258) 


(259) 


(260; 


(Cei) 


(2C2) 


VOL.     III. 


204 


814 

[5994] 

1263) 

(264) 

(265) 

(366) 

(2CC') 
(267) 

(268) 


(269) 


(270) 


APPENDIX,  BY  THE  TRANSLATOR  ; 

Using  the  same  notation  as  in  (100 — 104),  we  have,  identically, 

0  =  [x'li"  -  x"y').x  +  {x"y  -  xy").x'  +  (x,/  -  x'y).x". 

For  the  Jirst  term  is  balanced  by  the  fovrth,  the  second,  by  the  fifth,  and  the  third  by  the 
sixih  ;  so  that  the  second  member  is  identically  equal  to  nothing.  We  shall  now  represent 
the  double  of  the  area  of  any  one  of  the  plane  triangles  sah,  sbc,  sac,  figure  84,  page  792, 
by  including  the  corresponding  radii  in  brackets  ;  so  that  we  shall  have, 

[rr']  =  2.  area  of  the  triangle  sab  ;  ['"''■"]  =  2.  area  of  the  triangle  sbc  ; 

[;•;•"]  =  2.  area  of  the  triangle  sac. 

The  plane  of  the  comet's  orbit  being  inclined  to  the  ecliptic  by  the  angle  ç  (21)  ;  it  is 
evident,  by  the  principles  of  the  orthographic  projection,  that  the  double  of  the  projections 
of  the  areas  of  these  triangles, upon  the  plane  of  the  ecliptic,  will  be  obtained  by  multiplying 
the  expressions  (266)  by  cos.?,  so  that  we  shall  have, 

[«•']. cos. 9=  2. projection  oi  sab  ;         [rV"]. cos. ç  =  2. projection  of  sbc  ; 
[r-/'].cos.ip  =  2.projection  o(sac. 

We  shall  represent  the  co-ordinates,  of  the  projection  of  the  point  a,  hy  x,  y  ;  those  of  the 
point  b,  by  x' ,  y'  ;  and  tliose  of  the  point  c,  by  x"  y"  (100,  Sic.)  ;  as  in  figure  89,  where 
a,  |3,  7,  represent  respectively  the  projection  of  the  points  «,  b,  c,  of  figure  84,  upon  the 
plane  of  the  ecliptic.     Now  we  evidently  have, 


area  sa.p^ 


=  i< 


3,  X  o-aj  =  ix'y  ;         area  (SttjBj  =  |^Pi  X  a^Pj  =  iy'.{x' —  x)  ; 


(271) 


(272) 


(273) 


area  sjBp^  =  J«(3,  X  |3/3,  =  ix'y'  ; 

subtracting  the  sum  of  the  two  first  expressions  from 
the  third,  we    evidently  get  the  value  of  the   triangle, 

so.p  =  Ix'y'  —  ix'y  —  iy'.  (x'  —  x)  ; 

and  if  we  neglect  the  terms  ix'y'  —  i^'y',  which 
mutually  destroy  each  other,  it  becomes  as  in  the  first 
of  the  expressions  (273).  If  we  change  the  accents 
on  xy,  so  as  to  correspond  to  the  other  triangles 
s^y,  so-y,     we  shall  obtain  their  values,  as  in  (27.3). 

Triangle     «ap  =  i.(xy'—  x'y)  ;         triangle     s^y  =  ^.{x'jj"  —  x" ij')  ; 
triangle     so-y  ==  ^.{xy"  —  x"  y). 

Substituting  these  in   (268),  we  get  the  following  system  of  equations  depending  on  the 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


815 


principle  tiial  tlie  three  observed  places  of  the  comet  a,  b,  c,  figure  84,  are  in  the  same 
plane  passing  through  the  sun  ;  this  plane  being  inclined  to  the  ecliptic  by  the  angle     <p  ; 

xi/'—  I'l/  =  [rr'].cos.q,  ;  {r',j" —  x",/)  =  [r'r"].cos.<p  ;      {nj"  -  ^''y)  =  [rr"].cos.(p. 

Introducing  these  values  into  the  equation  (2(i3),  and  then  dividing  by  cos.cp,  we  get 
the  equation  (277).  This  equation  must  be  satisfied,  whatever  be  the  position  of  the  axis  of 
X  ;  and  if  we  change  this  axis  into  that  of  i/,  we  shall  find  that  the  values  x,  x',  x",  will 
become  y,y',y",  respectively,  without  altering  ['■'/■"],[/•/•"],[(•/■'];  hence  we  get  (278). 
In  like  manner,  by  changing  the  axis  of    x    into  that  of    z,    we  get  (279). 

0  =  [r'r"]  .  X  —  [n-"]  .  x'  +  [rr']  .  x"  ; 

0  =  ['■''■"].  y -K'].  y +[/T'].  y  ; 

Q=[r'r"].z-irr"].z'  +  [rr'].z"; 

We  may  remark,  that  the  whole  number  of  accents  on  each  of  the  terms  of  these  equations,  is 
three;  and  this  symvietry  obtains  in  many  other  of  the  equations  of  this  article.  The 
recollection  of  this  eireumstance  u'ill  sometimes  assist  in  distinguishing  the  symbols  from  each 
other.  If  we  substitute  .^=:  180''-)-©,  (10)  in  (108),  we  shall  obtain,  for  the  co-ordinates 
X,  y,  z,  at  the  first  observation,  tlie  expressions  (281),  and,  by  accenting  the  letters,  we  get 
the  values  corresponding  to  the  other  observations  as  in  (282,283)  ; 


a;  =  p.cos.a  —  iî.cos.@  ;  y    =  p.sin.u.  —  jR.sin.©  ;  z    =  p.tang.é  ; 

a;' ^  p'.cos.a' — jR'.cos.©';  /  =  p'.sin.a' — /î'.sin.©' :  s'  ^  p'.tang.â' ; 

x"=  p".cos.a"—  7î".cos.©"  ;         y"  =  p",sin.a"—  R".sm.(^";         z"  =  p".tang.()". 

Substituting  these  in  (277 — 279),  we  obtain, 

0  =  [;■'/■"] .  \  p.cos.a  —  i^.cos.© }  —  [rr"]  .  I  o'.cos.a'  —  Tî'.cos.©'} 

-I-  [rr']  .{!>". COS. i)."—R".cos.Q"]  ; 
0  =  [rV'J.f^sin.a  — iî.sin.©!  —  [rr"]  .{/.sin.a'  — iî'.sin.©'i 

+  [r/]  .  J/'.sin.a"  — /?".sin.©"i  ; 
0  =  [r'r"]  .  ^tang.a  —  [rr"]  ./.tang.ô'  -f-  [rr']  .  /'.tang.â". 

If  we  divide  (284,285,286),  by  any  one  of  the  areas  [r'r"],  [rr"],  [rr'],  we  shall  find, 
that  these  three  equations  contain  fve  unknown  quantities  ;  namely,  the  two  ratios  of  the 
areas,  and  the  three  radVi  p,  p',  p"  ;  any  two  of  which,  may  be  eliminated.  In  doing  this, 
we  may  observe,  that  the  equations  (284,  285),  are  wholly  independent  of  each  other  ;  and 
we  may,  in  either  of  them,  change  at  pleasure  the  direction  of  the  axis  of  x.  If  we  decrease 
the  angles  in  (284),  by  the  quantity  ©',  we  shall  get  (292)  ;  if  we  decrease  the  angles  in 
(285)  by  a,  and  then  change  the  signs  of  all  the  terms,  we  shall  get  (293)  ;  lastly,  if  we 
decrease  the  angles  in  (285),  by  ©',  we  shall  get  (294).  The  same  results  may  also  be 
obtained  by  combining  the  equations  (284,  285)  by  the  usual  methods  ;  thus,  if  we  multiply 


[5994] 

(2730 


(274) 

(275) 

(276) 

(277) 
(278) 
(279) 

(279') 
(280) 


(281) 
(282) 
(283) 


(284) 

(285) 
(286) 


(287) 
(288) 
(289) 


816  APPENDIX,  BY  THE  TRANSLATOR; 

[5994] 

(390)  (284)  by  cos.©',  and  (285)  by  sin.©',  then  take  tbe  sum  of  (he  products,  reducing 
them  by  [24],  Int.  we  shall  get  (292).  Again,  multiplying  (284),  by  sin.a',  also  (285)  by 
—  cos. a',     then  adding  the  products,  we  get  (293)  by  reduction,  and  using  [22],  Int.    Lastly, 

<29i)  multiplying  (285),  by  cos.©',  and  (284),  by  —  sin.©',  then  adding  tlie  products,  we 
get  (294).     The  equation  (295)  is  the  same  as  (286). 

0^[r';-"].{p.cos.(a-©')-iî.cos.(©-©')|-[,T"].lp'.cos.(a'-©')_/î'| 

+[rr'].5p".cos.(a"_©')-iî".cos.(©"-©')}; 

0=  [r'r"]  .{p.sin.(a'— a)+iî.sin.(©  — a')^— [n-"].7?'.sin.(©'— a') 

— [n-'].{p".sin.(a"— a')— iî".sin.(©"— a')|: 

0  =  [r'r"]  .{p.sin.(a-©')+J?.sin.(©'-©)|-[n-"].p'.sin.(a'-©') 

+[,r'l\ p".sin.(a"-©')-fi".sin.(©"-©') , . 
(995)      0  :=  [r'r"]  .p. tang. ^  —  [rr"].p'.tang.â'  -f  [rr'].p".  tang.t)". 

Multiplying  (294)  by     tang.ô',     and  (295)  by    — sin.(u.'  —  ©')  ;     then  taking  the  sum  of 
the  two  products,  we  find  that  the  terms  multiplied  by     p'     vanish,  and  we  get, 


(392) 


(393) 


(294) 


(396) 


(297) 


0  =  [;•'/■"]  .^itang.â'.sin.(a  —  ©')  —  tang.â.sln.(a'—  ©')  j  +  [/r'I.iî.tang.ô'.sin. (©'  —  ©) 
+  [rr'].p". \ tang.â'.sin.(a"— ©')  —  tang.ô".sin.(a.'—  ©')  |  —  [;T']./Î".tang.ô'.sin.(©"— ©'). 

Dividing  by  the  coefficient  of    f",     we  finally  obtain, 

„      [rV'J       |tang.ô'.sin.(a  — ©')— tang.lsin.(a'  — ©')} 
''  "^  [77]   ■  |tang.â".sin.(a'—  ©')  —  tang.â'.sin.(a"-(^|    '  '' 

tang.^'       I  r>V'].7?.sin. (©'  —  ©)  —  [rr'].J^".sin.(©"—  ©')  \ 
"^   [rr]    '  tang.â".sin.(a'  — ©')  — tang.()'.sin.(a"— ©') 

In  like  manner,  the  plane  triangles  sn'li',  sb'c',  sac',  figure  84,  page  792,  corresponding  to  the 
earth's  orbit,  give  by  using  a  notation  like  that  in  (266), 

(298)     \RR''\  =  2.area  of  the  triangle  sab'  ;         \R'R"\  =  2.area  of  the  triangle  sh'c'  ; 

[IiR"'\  =  2. area  of  the  triangle  sa'd. 

The  area  of  any  one  of  these  triangles,  as  sa'I),  is  found  by  multiplying  its  base  sa'  =  R, 
by  half  the  perpendicular  let  fall  upon  it  from  its  vertex  b',  or  by  i  R'.sin.a'sù'  ;  therefore, 
this  area  is  represented  by     ^RR'.sm.a'sb'  ;  and  as  the  angle    a'sb'=  A'  —  A=0  —  ©, 

'■^^^  the  area  becomes  i  E/?'.sin.(©' — ©).  Substituting  this  in  the  first  expression  (298), 
we  get  the  first  of  the  equations  (300)  ;  in  like  manner,  the  second  and  third  of  the  formulas 
(298), become  like  those  in  (300).     Inexactly  the  same  way,  we  get  the  expression  [300']  ; 

C299')    observing,  that  the  angle  asb  =  v' — v  ;  the  angle  csb  =  v" — v'  ;  the  angle  asc  ^v"  —  v  ; 

[RR]  =  RR'. sm.{Q'  -  Q)  ;     [R'R"]  =  R'R".sm.{Q" -Q')  ; 
^3»°)  [RR"]  =  RR".sm.{&'—&)  ; 

(300)       [rr']  =  rr'.sin.(i-'— 1»)  ;  [rr"]  =  r'r" .s\n.{;v"  —  v')  ;  \>r"]  =  rr".sm.{v'  —  v). 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  817 

[5994] 
The  second   of  the  equations   (300),  gives  the  first  expression   (301)  ;    multiplying  its 

numerator  and  denominator  by    R.sm.{(;?)' — ©),    we  get  its  second  expression  ;  substituting 
in  its  denominator  the  value,   [Rli']   (300),  we  get  the  last  of  the  formulas  (301)  ; 

R"  ,in  (B"-m  =  ^^'^"]  =  L^'i^n  ■7?sin.(C^'-G)  _  [R'R"].R.s\n.{Q' -Q) 

'^    '^  '^  R'  liRf.s\n.{&  —  &)  [iuf]  '      (3"^ 

substituting  this  last  expression,  in  the  numerator  of  the  second  line  of  the  second  member 
of  (297),  we  get, 

"  —  ['"''""]       tang.â'.sin.(a  —  fy)  —  tangJ.sin.(a'  —  ©') 
['•'•'J    '  tang.d".sin.(a'—  f^')  —  tang.ô'.  sin.(a"  — ©')  "'' 

+    \  I^  _  [^'^"]  ]      7?.tang.é'.sin.(g/  —  Q) ''""'' 

I    [r/J         lRR']y   tang.d".sin.(a'— ©')— tang.é'.tang.(a"— ©')    " 

Now  putting  for  brevity, 

^^^    tang.é^sin■(  g  —  Q')  —  tang.é.sin.  (  a'  — €i')    . 

tang.r.sin.(a'— ©')  — tang.â'.sin.(a"— ©-)  '  (303) 

_  tang.O'.sin.  (©'  —  ©) 


tang.a".  sin.(a'  —  ©')  —  tang.O'.  sin.(a" —  ©')    '  (304) 

the  preceding  expression  of    p"  (302),  or  M.p  (29),  becomes  of  the  following  form  ;  in 
which  nothing  is  neglected; 


'—[^•-.■'+1[^] -[IS  I  •«=•«• 


(305) 


(30G) 


Dividing  this  last  expression  by     p,     we  get  the  correct  value  of  M.    If  we  suppose,  as  in 
Olbers's  hypothesis  (53),  that. 


[//■"]         [R'R"]        t"—t' 


[n']  [RR']         t'—t    ' 

the  term  depending  on    M^    will  vanish  from  (306),  and  we  shall  have,  very  nearly, 


(307) 


hence, 


f f 

I'  If I  "^    '  (308) 

^  i"—f      ^j  ^  t"—t'       tang.^'.sin.(a  — ©')— tangJ.sin.(a'— ©') 

t' —  t'  ^    '  ~  t' —  t  '   tang.a".sin.(a'— ©')  —  tang.é'.sin.  (a"—  ©')  "  (309) 


This  expression  of  M  is  the  same  as  the  approximate  value,  assumed  by  Dr.  Olbers  (30)  ; 
as  is  evident,  by  substituting  in  it  the  value  of  m  (28),  and  making  a  slight  reduction.  To 
estimate   the  value  of  the  neglected  terms   in  the   value    of   M,  we  may   proceed   in  the 

VOL.  III.  205 


818  APPENDIX,  BY  THE  TRANSLATOR; 

[5994] 


(310) 


(311) 


(312) 


(313) 


(314) 


following  manner.  Taking  the  rectangular  co-ordinates  of  the  comet,  in  the  plane  of  its 
orhit,  and  representing  them  in  the  three  observations,  by  x,  y,  x',  y',  x",  y";  putting 
|ji=l,or  neglecting  the  mass  of  the  comet,  in  comparison  with  that  of  the  sun,  as  in 
[760^'"],  we  obtain  from  [^61],  by  accenting  the  symbols,  the  following  equations  , 

d'^K.'     ,     x'  _  dY         y' 

"rf^  +  /3  —  0  ;        d?  +  ^2  =  ^- 

Now  if  we  take,  for  the  origin  of  the  time  t,  tlie  moment  of  the  second  observation,  when 
the  co-ordinates  are  x',  y'  ;  and  suppose  that  at  the  end  of  the  time  t,  these  co-ordinates 
become  x",  y",  respectively  ;  we  shall  have  by  Taylor's  or  Maclaurin's  theorem  [G07a] 
the  expression  (315).  Substituting  in  this  the  value  of  fPx',  and  of  its  differentials,  deduced 
from  the  first  of  the  equations  (312),  we  shall  get  (316)  ;  which  is  easily  reduced  to  the 
form  (317); 


(317) 


(315)  x"=x'+^.^  +  i.    —.fi+i.---^    .t^+fcc. 


,       „..  ,     -       ,  C  f/x'     1       rfr'   3x'  )        „ 

'     -"  ^    -'•*  ^  I  dt    r  3       dt     ?•'*  5 


d\.'  J     X 


=  -l'-*-;  +  *V^-S  +  -|  +  l'l'-*7-+-l 


In  like  manner,  we  can  obtain  the  similar  expression  of  y".     The  intervals  of  the  times 

(318)  between  the  observations,  namely,  t'  —  i,  i" —  t',  t"  — t,  are  to  be  reduced  to  parts  of  the 
radius,  by  multiplying  them  by  k  [5937(8)]  ;  and  we  shall,  for  brevity,  express  these  products 
by    r,    t',    t"  ;     as  in  (319)  ;  observing  that  these  symbols  have  the  same  symmetry  as  in 

(318)  (279^)  namely,  that  the  number  of  accents  in  each  of  the  equations  (319)  is  three.  We 
shall  also  use  the  abridged  expressions  (320—323). 

(319)  t"=^'.(/'  — 0;  'r  =  k.{i"  —t');  r'  =  l:  {t"  —  t);  r'=r+'r"; 

t"2  .r"3     dr' 

(320)  «^,=  1— i.  -^— J  ,— ,  .  — +&C.; 

(321)  w„=r"—  i.^  —  hc.; 

(323)  W"=  T    —  -^  .  ^  +  &C. 

While  the  body  moves  from  the  second  point  b,  to  the   third  point  c,  figure  84,  the  time 
increases  from   t'  to  «",  the  increment  being  t"—i',  or  r    (319),  expressed  in  parts  of  the 

(324)  radius.     Substituting  this  for     t    in  (317),  we   get  the  expression  of   x",   (328),  using  the 
symbols  (322, 323)  ;  in  like^  manner  we  get  the  similar  expression  of    y"   (329).     If  we 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.:  819 

[5994] 
change,  in  this  calculation,    t"  into   t,    the  quantity    t    will  change  into     — t"    (319);  by     <''-=) 
which  means    w'  (322),  changes  into   u\  (320),  and  w"  (323)  into  — w^^  (321);  making 
these  changes  in    x",    y"    (328, 329),  we  get    x,    y    (326,327).      Finally   as  the  jilane 
of  the  orbit  is  taken  for  the  plane  of  projection  (310),  we  shall  have     z  =  0,     z"=  0,     as 
in  (32T',329'). 


It 
dy' 


X  =  w,  •  X'  —  «'„  --^  ;  (=«6) 


y  ==  u', .  Y  —  w,, .  ~    ;  (32-) 

z  =  0  ;  (32-) 

x"  =  w' .  X'  +  rv".  ~  ;  (328) 

at 

II  I        I     s        11    ^h'  (329) 

Z"  =  0  (329') 

Multiplying  (326)  by  y',  and  (327),  by  — x',  then  taking  the  sum  of  the  products, 
we  get  the  first  expression  (331).  Again,  multiplying  (329)  by  x',  and  (328)  by  — y'; 
then  taking  the  sum  of  the  products,  we  get  the  first  expression  (332).  Lastly,  multiplying  (330) 
(326)  by  (329),  also,  (327)  by  (328),  and  subtracting  the  last  product  from  the  preceding, 
we  get  the  first  expression  (333).  The  second  form  of  either  of  these  expressions,  is  easily 
deduced  from  the  first,  by  the  substitution  of 


(330) 


s.'  dy'  —  y'  d x'  

rf^ =  ^a-{y  -  e^)=^p, 

which  is  easily  deduced  from  [366,596c],  using  (311),  and  [5985(5)]. 

(x'f/y'  —  y'd\') 
xy'  —  x'y  =  w„  . -^ =  w„  .  \/p  ;  (33i) 

U'dy'  —  y'dx') 
x'y"—  x"y'  =  10"  . ^  -^         '  =  w".  s/p  ;  (332) 

(x'f/y'—  y'(/x')                       (x'Jy'  —  y'dx'\ 
xy"_  x"y  =  w,Ao" .  ' '-^ ■'  +  lo'.tv,,  .i l—J. L  =  {iv,.io"  +  w'.w,,) .  x/p.       (333, 

Now  the  expressions  (320 — 323),  give  successively,  by  using     t'  =  t  -\-  t",     (319), 

,.,.«/'  =  T-i.--i.r._-f&c.;  w'.W„='r"-l—  _i..".-+&c.;     ,,,,, 

u;ac"-{-w'.w„=  t+t"—  —3.  |t3+3t2.t"+3t.t"2-[-t"3|+&:c. 

"'"  (335) 

T'3 
=  ^'—i-     ^+^''-'  (336, 


820  APPENDIX  BY  THE  TRANSLATOR  ; 

[5994] 

Substituting  in  the  first  members  of  (331 — 333),   the  following  expressions,  which  are 
deduced  from  (274),  by  putting     <p  ^  0,     as  in  (310). 

(337)  xy'  —  x'y  =  [rr']  ;  x'y"—  x"y'  =  [r'r"]  ;  xy"  —  x"y  =  [rr"]  ; 
and  in  their  last  members,  the  values  (321,323,336),  we  get, 

(338)  [r/]  =  \r"  —  -X3.r"^—k.c.lyp  =  r".\l—~    .  r"^  —  ^A Yp  ; 

(339)  [,V']=^T  —-TTs'  'r^  +  Sic.  >.v/p  =  '^•jl  ~7^  •  1-2+  &c.>.v/p  ; 

Dividing  these  expressions,  the  one  by  the  other,  we  obtain, 


(340) 


(341)  ^-^    =    ^  J    1  _  _L  .   (^2    _    ^"3)   +    &c.      ]; 

[rr]  r"     I  6r'3     ^  ^^  <,  ' 


[r'r"] 

b 

[r 


(343)  Ï;:^   -      r'r         Qr'  •   "^  M   i-    ^C.     j  . 

As  these  formulas  may  be  used  for  any  of  the  heavenly  bodies,  we  shall  obtain  the  expressions 
(344—346),  corresponding  to  the  earth's  orbit,  by  merely  changing  r,  r',  r",  into  R,  R,  R  , 
respecti  vely, 


[RR"] 


1 


(344)  ltL!±J  =  _  .  M  —  -5-3  .  ( 


.a 


6R 


T 


'-)  +  &c.    I  ; 


[RR 

(345)  <■ 


[RR] 

^  =  -  .  5  1  — ^  •  (^"  -  ^"-)  +  ^c.   \; 
[RR]  r"    I         6R3  5 

i^E]    -^.\   1 î-    .  (r'^-   r.)    +    &c.    ?  . 

C3«)      If  the    intervals  between   the  three    observations  be  equal,   or     t"  =  r,     we  shall  have 
t3  t"2  =  0,     and  then  the  expressions  (341,344),  will  give,  hij  neglecting  terms  of  the 

jourth  order  in    r,  r',    (333— 340),  or  of  the  ^Aùy/ order  in  the  factors  of —,  (341,344); 

(348)  [^         [Rm^^^^:^     (319), 

[rr]  [RR]  t"  i'— <     ^       ^ 

which  agrees  with  the  supposition  of  Dr.  Olbers  (307).     Hence  ive  see  the  great  advantage 
^^^'     of  having  the  intervals  of  time  between  the  observations  equal  to  each  other,  in  computing  the 


C03IPUTATI0N  OF  THE  ORBIT  OF  A  COMET. 


821 


orbit  of  a  comet,  ly  this  method;  because  it  makes  the  factor  of  M„  R,  (306),  nearly 
insensible;  and  gives  a  more  accurate  value  of  the  expression  M.p,  than  it  would  if  the 
intervals  u-ere  unequal.  If  observations  cannot  be  obtained,  in  which  the  intervals  r,  t" 
are  equal  to  each  other,  we  must  select  those  which  are  nearly  equal  ;  in  order  to  diminish 
as  much  as  possible  the  effect  of  the  factor  t^  —  t"-.  If  R'=r',  the  expressions 
(341,344),  become  equal;  hence  it  is  evident,  that  if  r'  be  nearly  equal  to  /?',  and 
the   intervals     t,  t"     differ  considerably  ;  it  will  be   rather  more   accurate   to  compute 

equal   to   it,   than  to   put   each    of  these 


• ,     from  the  solar  tables,  and  put     f— -: 

[RR]  '^         [rr'] 


quantities  equal  to      —     (34S).     Finally,  we  may  observe,  that  after  we  have  computed, 

by   a   first   approximation,   the   values   of    p,  r,  r",     we  may,  by  interpolation,   find    an 

approximate  value  of    r,    by  supposing  the  values  to  increase  uniformly  ;  by  which  means 

we  shall  have, 

t' —  t 
r"  =  r  -\ .  (r" —  r). 


[5994] 

Grout  ad- 
vantage of 
having  the 
(319) 

intervals  of 
time  equal 
between 
the  obser 
vations. 
(350) 


(351) 


(352) 


(353) 


With  these  we  may  obtain  the  corrected  value  of  the  function  (341),  to  be  substituted 
in  (306),  to  get  a  more  accurate  value  of  M;  with  which  the  calculation  can  be  repeated, 
in  any  extreme  case,  where  it  shall  be  found  necessary. 

In  the  case  where  the  value  of  M  (309),  appears  under  the  form  of  M  =  ^  ,  we 
may  deduce  the  value  of  p"  =  M.p  from  the  equation  (293),  instead  of  (294,  295), 
which  are  used  in  finding  (297).  Then  as  radius  p'  does  not  occur  in  (293),  we  shall 
have, 

[r'r"]      sin. (a' — a) 
''   ~  [rr']  '  sin. (a."— a')  *  ** 


+ 


[r'r"].R.sm.(f£)—a.')—[rr"].R'.  sm.{0'—o.')+ [rr'].sm.(0"—a.').V.~ 
[rr']. sin. (a"  —  a') 


If  we  divide  the  expression  (341)  by  (344),  we  get,  by  a  slight  reduction,  the  expression 
(357)  ;  in  like  manner,  from  (342,  345),  we  get  (358)  ,  lastly,  from  (343,  346),  we  obtain 
(359).     The  equation  (360),  is  evidently  identical; 


[r' 

r"] 

[rr'] 

[r 

n 

[' 

-r'] 

[;■ 

■r"] 

['" 

'r"] 

[rr'] 

[RR] 


^  ''     \R'^         r' 


+  &c. 


+  &c.  ]  ; 


'2    _     ^3)    .      (    J- 


I 


(334) 


(355) 


«56) 


[rr'] 
VOL.    III. 


[RR'] 


(357) 


(358) 


(339) 


(.3011) 


206 


822  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5994] 

Taking,   as   in    (269),  the    ecliptic    for  the   plane  of  projection  ;  we  shall   represent    the 

(361)  rectangular  co-ordinates  of  the  earth,  by  X,  Y,  at  the  first  observation  ;  X',  Y',  at 
the  second  observation  ;  X",  Y"  at  the  third  observation  ;  hence  the  identical  equations 
in  the  earth's  orbit,  corresponding  to  (277,278),  In  the  comet's  orbit  ;  becomes, 

(362)  0  =  [R'R"] .  X  —  [RR"]  .  X'  +  [RR']  .  X"  ; 

(363)  0  =  [R'R"]  .  Y—  [RR"]  .  Y  +  [RR] .  Y"  . 

If  we  take  for  the  axis  of  X,  the  line  whose  longitude  is  lSO''+o-',  we  shall  evidently  have, 

(364)  Y  =  iî.sin.(©  —  a')  ;         Y'  =  R'.  sin.(©'—  a')  ;         Y"  =  R".  sln-(©"—  a  )  . 
Substituting  these  in  the  numerator  of  the  second  line  of  (356),  it  becomes, 

(365)  [>■'>■"]  .  Y  —  [n"]  .  Y  +  [rr']  .  Y". 

If  we  substitute,  in  this  expression,  the  values  of    [»•';"],     [rr'],     [rr'],     (357,  358,  360) 
and  neglect,  for  a  moment,  the  terms  depending  on  the  factor     ^ -j     ^^  ^vill  become, 

(366,  ^^  . I  [R'R"] .  Y  -  [RR"] .  Y  +  [RR] . F'  j  ; 

and  as  this  vanishes,  by  means  of  the  equation  (363),  it  will  be  only  necessary  to  retain  the 

(367)     terms  of  (357,  358),  which  are   multiplied  by  that  factor     — — —^.     In  the  case  now 

under  consideration,  this  factor  is  very  small,  because  when  the  apparent  motion  of  the 
comet  is  in  a  great  circle,  we  shall  have  r'  =  R'  [780"]  ;  and  if  the  intervals  i'  —  t 
i"  —  tf,  or  r",  T,  be  nearly  equal,  we  shall  have  ■f^  —  t"^  =  0  ;  and  we  may 
therefore  neglect  the  product  of  this  quantity,  by  the  preceding  factor  in  (357)  ;  putting  also 
T '=  2t"  in  the  factor  r'^  —  t"2  (35S),  by  which  means  we  get  -|.(t'2  —  t"2)=:1t"2; 
hence  the  term  of  (358),  depending  on  this  factor,  becomes, 


(368) 
(369) 


(370) 


[RR 


/]'^      \r'^      ?-'V     ^     \r">      T'y     '      \R'^      r'y' 


(371) 


(372) 


[RR 

nearly;  as  is  evident  by  using  only  the  first  term  of  the  second  member  of  (345). 
Substituting  this  in  the  numerator  of  the  second  line  of  (356,or365,&;c.),  and  putting  in  its 
first  line, 

p^  =^  =  '-P^      (341,369,319), 

we  finally  obtain  the  following  value  of  p",  which  can  be  used  in  the  case  now  under 
consideration,  ivhcn  the  geocentric  longitudes  a,  a',  a",  vary  from  each  other  much 
more  than  the  geocentric  latitudes    é ,  è',  ô"  ; 

t"  —  t''      sin.(a'  —  a)         ,    ,         iî'.sin.(a'— ©')    /I  1    \ 

^  —  t'—t  •  sin.(a"—  a')  ^     ^  sin.(a"-a')        \R^  r  '  J 


COMPUTATION  OF  THE  ORBIT  OF  A  CO]\IET.  823 

[5994] 
We  may  obtain  another  form  of  the  expression  of    p"    by  eliminating    p'   from  (292,295)  ; 

this    is    done   by  multiplying  (292)  by     — tangJ',     and  (295)  by     cos.(a' — ©  ),     and 

taking  the  sum  of  the  products,  by  which  means  we  get, 


(  —  p.tang.â'.cos.(a.  —  ©')  +iî.tang.ô'.cos.(0  —  ©') 
0  =  [rr]  .  j  ^         \  —[rr"].R'.  tang.â' 

'  -j-  p. tang. â. COS. (o 


5-(©-©')) 
(a'-©')      S 

(  —  p  '.  tang.é'.cos.(a"—  ©')  +  R".  tang.ô'.cos.(  ©"  —  ©  )  ) 

+  [n-].j  [ 

(  4-  p"-  tang.d".cos.  (a'  —  ©')        ) 


(373) 


Dividing  this  by  the  coefficient  of    P  ,     we  obtain, 

, [rV  ]     C  tang.^'.cos.(a  —  ©')  —  tang.é.cos.(tt.'  —  ©')  , 


p' ,  . 

[rr']     ^tang.^'.cos.(a-'  —  ©')  —  tang.()'.cos.(a"  —  ©')i 


(37-1) 


_   ^  [>■;•].  JZ.tang.^'.cos.(©  —  ©')  —  [rr"].  R.  tang.â'  -fJVr'jJ?^  tang  J'.  cos.(©"—  ©')  \ 
(  [rr'].  \  tang.d".  cos.(a'  —  ©')  —  tang.â'.cos.(a"— T©^)]  ~      "^ 

The  second  line  of  this  expression  may  be  reduced,  by  a  process  similar  to  that  in  (364  &c.). 
Taking  for  the  axis  of  X  the  line  whose  longitude  is  180''+©',  we  shall  have 
in  like  manner  as  in  (364), 

X  =  fi.cos.(©-©'),         X'=./î'.cos.(©'-©')=i2';         X=i?".co3.(©"-©')  ;    (375) 

and  then  the  numerator  of  the  expression  in  the  second  line  of  (374),  becomes. 

j  [r'r"lX-[rr"\.X  +  [rf].X'  [ .  tang.ô'.  ,376) 

If  we  substitute  in  this,  the  parts  of  \r'r"],  [rr"],  [rr'],  (357,358,360),  which  depend 
on  the  first  term  of  the  second  members,  it  becomes, 

[W]   •  ^  ^^'^"^-  ^  ~  [^«'  ]-^'  +  [Ri?'].X"  S    ;  (377, 

which  vanishes,  by  means  of  (362).  Hence  we  obtain  the  same  result  as  in  (367);  namely, 

that  it  is  only  necessary  to  notice  the  terms  depending  on  the  factor     —    —  —  •     and  by     <^'*> 

supposing  the  intervals  i'  —  t,  t"—  t'  to  be  nearly  equal,  we  shall  find  as  in  (370),  that 
the  only  part  of  this  numerator,  which  it  is  necessary  to  notice,  arises  from   that  part  of 

-^^,     which  is  denoted  by     -\- ^.rr'.f--^  —  ^\     (370).      Substituting  this  in  the     (379) 

second  line  of  (374),  and  puttiiig,  in  the  first  line,  the  value  (371),  we  finally  obtain   the 
following  expression  of    p",     which  can  he  used,  in  this  excepted  case,  when  the  geocentric    (3790 
latitudes     ê,ê',è",     vary  from  each  other  more  than  the  geocentric  longitudes     a   a'  a"- 


824 

APPENDIX,  BY  THE  TRANSLATOR; 

[5994] 

t" —  t      \  tang.«'.cos.(a  —  ©')  —  tang.â.cos.(a'  —  ©') 

^  ~  V  —  t'  ^tang.â".cos.(ciL' — ©')— tang.ô'.cos.(a" — ©') 

(380) 

^,       ,     ^                                iî'.tang.â' 

'    ^     *       ^  tang.ô".  cos.(a'— ©') — tang.ô'.cos.(a" — @') 

(381) 
(382) 

(383) 

(334) 

(385) 
(386) 

(337) 

(388) 
(389) 
(390) 

(391) 
(392) 

(393) 

(394) 
(395) 


For  convenience  in  the  calculations  we  have  arranged  the  formulas  (372,  380),  as  in  the 
table  (387 — 392).  If  we  neglect  the  term  of  p''  (372),  depending  on  tt',  and  use 
the  symbol  M'  (387),  it  becomes  p"  =  JkZ'.p,  so  that  M'  represents  an  approximate 
value  of  M,  (29).  With  this  we  may  compute  the  equations  (31 — 33),  and  from  thence 
deduce,  as  in  (192),  the  approximate  values  ?',  r",  p.  This  value  of  p  we  shall  represent 
by   (p)  ;  and   from    r,   r",     we   may  find  the  approximate   value  of    r     (353),  to  be 

used   in   computing  the   term  of  the  order     "'-l^g  —  ~A-,     vvhich  occurs  in  (372). 

)     (319),  in  the  second   term  of  (372),  and  then  dividing 

the  whole  of  the  second  member,  by  the  expression  of  M'  (387)  ;  we  find  that  the  quotient 
becomes  equal  to  F'  (388)  ;  consequently,  this  expression  of  p",  will  become  as  in 
(389).  In  like  manner,  by  using  the  abridged  values  of  M",  F"  (390,391),  we  find 
that  the  expression  of  p"  (380),  becomes  as  in  (392)  ;  (p)  being  as  before,  the  value 
of  p,  deduced  from  the  first  approximation,  in  which  . 
unity. 


is  supposed  to  be  equal  to 


M'  = 


t" — t'     sin. (a' —  a,) 
t' —  t  '  sin.(a" — ^0,')  ' 


F'    =    l+ir' 


sin.(a'— ©0 
sin.  (a'  —  a) 


(p)  ■  \R''      ' 

p"  =  M.p  =  M.F'.  p  ;        or        M=M'.  F: 

t"—t'    tang.é'.cos.(a— ©')— tang.é.cos.(a'— ©') 
"^^"^  fZTt  '  tang.â".cos.(a'-©')— tang.â'.cos.(a"-©') 


F"=l+h^ 


tang.ô' 


tang.ô'.  cos.(a- 
p"=^.p=iM".F".p; 


R 

.  e>')-tang.â.cos.(a'—  0)  '(p)' 

M=M".  F". 


1 

m' 


or 


To  Le  used  when 
the  longitudes 

a,  a',  a", 

vary  faster  than 
the  latitudes 


To  he  used  when 
the  longitudes 

0,,  a',  01", 

vary  slower  than 
the  latitudes 

6,  6',  6". 


P" 


If  we  compare  the  correct  value  of    M=-     (306),  with   its    approximate    values 

(309,  387,  390),  we  shall  find,  that  the  first,  or  general  form,  is  by  far  the  most  accurate  ; 
especially  when  the  intervals  of  the  observations  are  nearly  equal,  or  r^— r"2  =  0; 
since  in  this  case,  the  value  of  M  (309),  is  correct  in  terms  of  the  second^  order,  in 
r  r",  inclusively  (306,347, 8ic.)  On  the  contrary,  the  values  of  M  (389,392), 
aie  found  by  multiplying  the  assumed  values  M',  M"  (387, 390),  by  the  factors  F',F" 
(388, 391),  which  contains  terms  of  the  second  order  in    r,    r"  ;  so  that  these  expressions 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET. 


825 


[5994] 

(395) 

(H90; 
(397) 


of  M  may  be  considered  as  less  accurate  than  that  in  (30)  or  (309),  by  at  least,  terms 
of  one  order,  in  t,  t'.  Now  from  the  mere  inspection  of  the  approximate  values  of  M, 
given  in  (309,  387,  390),  it  is  evident,  that  when  the  apparent  path  of  the  comet  is  near  the 
ecliptic,  and  the  latitudes  è,  6',  é"  differ  but  little  from  each  other,  the  expressions  (309,  390), 
will  have  very  small  numerators  and  denominators  ;  therefore  the  resulting  value  of  M 
or  M'  may  be  considerably  affected  by  the  imperfections  of  the  observations  ;  but  this 
would  not  be  the  case  with  the  expression  (387),  supposing  the  longitudes  of  the  comet  to 
vary  rapidly.  On  the  other  hand,  when  these  longitudes  vary  slowly,  the  expression 
sin. (a' — a),  sin.(o.' — a'),  are  small  ;  consequently,  the  numerator  and  denominator  of 
(SSI),  may  be  so  small  that  the  errors  of  the  observations  can  have  an  important 
influence  on  the  resulting  value  of  M'.  Hence  it  follows,  that  when  the  expression  (309) 
becomes  uncertain,  on  account  of  the  smallness  of  its  numerator  and  denominator,  we  can 
use  the  expressions  (387 — 3S9),  if  the  longitudes  of  the  comet  vary  more  rapidly  than 
the  latitudes  ;  or  the  expressions(390 — 392),  if  these  longitudes  vary  slowly  in  comparison 
with  the  latitudes.  The  method  of  using  the  formulas  (387 — 392),  is  so  similar  to  that  in 
the  preceding  examples  (173,  &c.),  that  it  is  unnecessary  to  give  any  examples  for  illustration. 
We  shall,  therefore,  close  our  remarks  on  this  method,  by  observing,  that  after  the  approximate 
values  of  the  elements  have  been  obtained,  we  may  correct  them  by  taking  more  distant 
observations,  as  we  have  already  observed  in  [820"',  Sic,  849a,  &c.]. 

Since  the  preceding  article  was  prepared  for  this  appendix,  a  new  method  of  computin'' 
the  orbit  of  a  comet  has  been  proposed  by  Mr  Lubbock,  and  published  in  the  fourth  volume 
of  the  Memoirs  of  the  Astronomical  Society  of  London,  and  in  a  separate  pamphlet  "On 
the  determination  of  the  distance  of  a  comet,  &ic.;"  in  which  he  has  reduced  the  question 
to  the  solution  of  a  quadratic  equation.  As  we  have  not  made  any  numerical  computations 
by  this  process  ;  v.e  shall  restrict  ourselves  to  the  explanation  of  the  principles  of  the  method, 
with  such  illustrations  as  may  be  necessary. 

If  we  suppose  the  intervals  of  time     t' —  /,  t'' —  t',     between  the  observations   to    be 
equal,  we  shall  have     r"  =  r     (319),  and    by   neglecting    terms   of  the   order     ^^.     we     '^"'' 
shall  have,  as  in  (320—323), 


Substituting  these   in    (326 — 329'),   we    get,   by  taking  the    differences    of  the    resulting 
expressions. 


f/x' 


X    X 


Y"  —  \ 


dy' 


rfz' 


0. 


(308) 
(399) 

(400) 

(40  J) 
(402) 

(403) 


LuI)bock*a 
method  of 
computing 
the  orbit  oi 
a  comet. 
(404) 


(400; 


(^f  '  ''  '   (It  '  cli  mi) 

The  sum  of  the  squares  of  these  iliree   equations,  produres   the  first  îiik!   scccnd  of  the 

VOL.  III.  207 


826  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5994] 

following  expressions  of    c^  ;     from  the  second  we  easily  deduce  the  third  by  means  of  the 

(407)      formula  [572, line  5],  putting     (j.  =  I,     as  in  (311)  ; 


(408) 


The  values  of  r^,  r"^,  may  be  deduced  from  ;'^  and  its  differentials,  by  Maclaurin's 
theorem  [G07«],  in  the  same  manner  as  we  have  obtained  x"  from  x'  in  (315,&c.)  ; 
and  we  shall  have, 

(«9)  r^  =  r"2  —   r  .  -V^  +  J  r2.  ^^  —  &;c. 

dt  dr 

Subtracting  2r'^  from  the  sum  of  these  values  of  r^,  r"^  ;  neglecting  the  terms  depending 
on     T^,     and  the  higher  powers  of    -r,  we  get, 


(411)  ^2  _  2/2  +,."2   =   ^2. 


dfi 


The  second  member  of  this  equation  may  be  reduced,  by  means  of  [595],     For  if  we  put 
(■»H'>      for  a  moment     r  =  r^,     the  expression  [595],  becomes,  by  supposing  as  in  (407')     ti-^l, 


1  fh-2 

412))  2  r* .  r  —  ^^-„  ;=  h^. 


a 


Adf 


Taking  its  differential,  and  dividing  by     di- ,     we  get, 

1  ddï 

(412)  r-* — 7-„  =  0  . 

a         2dt^ 

Re-substituting  the  value  of    r,     and  making  a  slight  transposition  in  the  order  of  the  terms, 
we  get, 

cP.  (,-2)  1  1 

(413)  !^ — :  = • 

2dt^  r  n' 

hence,  the  equation    (411),  becomes, 

(414)  ,2_2,.'2+r"2=2r2/l    _    1 

\r         a 

Mr  Lubbock's  method  is  grounded  on  the   two  equations   (408,414);  by  substituting   the 
values  of    c,  r,  r' ,  r",     in  terms  of    p',     and  assuming  the  following  expressions  of    ,",  p", 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  827 

[5'J94] 

p  =  ^1  •  p'  ;  (-115) 

p"    =    X^  ,   p'   .  (4)6) 

Tlie  values  of    X, ,  X„ ,     may  be  deduced  from  the  equations  (294,295),  by  the  ehmination 
of    p".     For  if  we   multiply   (294)  by     tang.d",     also,  (295)  by     —  sin.(a"— ©'),     and     d") 
take  the  sum  of  the  products,  we  shall  find  that  the  terms  depending  on     p"     will   vanish, 
and  we  shall  have, 


0  =  [rV"].p.{tang.â".sin.(cL  — ©')  —  tang.().sin.(a"— ©')}+  [r'r"]./î.tang.ô".  sin.(0— ©) 
_[_[,-r"].p'.|_tang.â".sin.(a'— ©')+tang.ô'.sin.(a"— ©')}— [rr'].i?".tang.é".sin.(©"— ©'). 

Dividing  by  the  co-efficient  of  p,  we  obtain  (419).  In  like  manner,  if  we  multiply  (294) 
by  tang.^,  also  (295)  by  — sin. (a  —  0'),  then  take  the  sum  of  the  products,  and 
divide  by  the  co-efficient  of    p",     we  shall  get  (420)  ; 


[rr"]     C  tang.é'.sin.(a" — ©' 
f—  [r')-"]  ■  (  tang.â.sin.(a"— ©'; 


—  ©')  —  tang.é".sin.(a'— ©') 


P 


+ 


p"  = 


+ 


')  — tang.d".sin.(a—  ©') 

tang.a"       \  [r'r"].R.sm.{©'  —  ©)  —  [  r  r'] .R".  sin. (©"—  ©')  \ 
[r'r"]      '         tang.â.sin.(a"—  ©')  —  tang.d".  sin. (a  —  ©') 

[rr"J      C  tang.é.sin.(oL'  —  ©')  —  tang.ô'.  sin. (a  —  ©') 


5')  —  tang.ô'.  sin.  (a  —  ©')  )       , 

^')— tang.()".sin.(a  — ©')  \   '^ 


[rr'J       I  tang.â .  sin. (a"  —  ©'] 
tang.ô      {[?y].R".sin.(©"  —  ©')  —  [rV'].i?.sin.(©'  — ©)| 


[rr]    '  tang.ô.sin.(tt." — ©') — tang.é".sin.(a  —  ©') 

Substituting  in  the  last  term  of  each  of  these  expressions,  the  value  of    R".  sin.(©" —  @') 
(301),  we  get, 

_  [  rr'q     C  tang.<!'.sin.(a."—  ©')  —  tang.é".sin.(a^—  ©Q  ) 
P  ==  |- ,./,-'/]  •  I  tang.â.sin.(a" — ©')  —  tang.â".sin.(a  —  ©')  5  '  ^ 

(   [r'r"]  _  [R'R"]    )   [rrq    i^.tang.y^sin.((2)' —  ©) 

'^  i  Trr^  [^^']    >  ['■''^'l'  tang.lsin.(a"  — ©')— tang.â".sin.(a  — ©')  ' 

[rr"]    <;  tang.a.sin.  (a'  —  ©Q  —  tang.é^sin.  (g  —  0') 
''""  [rr^  '  (  tang.ô.sin.(a"—  ©')  —  tang.ô".  sin. (a—  ©') "  ^' 


-1 


[r'r"]  _  [R'R"]  } ■R.tang.lsin.(©^  — ©) 

Irr']  [RR']   )  *  tang.é.sin. (a"—  ©')  —  tang.ô". sin.faT^^^©^' 


If  we  neglect  those  terms  of  the  second  members  of  these  equations,  which  are  multiplied 
by  the  extremely  small  quantity     -j— rr  —    [RR]     ^'^*^^)'  ^^^  ^'^^^^  '^a^^' 


(418) 


(419) 


(420) 


(421) 


(422) 


828  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5994] 

^^^  ^  [rr"]     ^  tang.é'.sin. (a^' - ©Q  —  tang.é".  sin.(a'  —  ©Q  ^ 

''        [r'r"]  ■^tang.â.sin.(a"— ©')  — tans.â".sin.(tt  — ©')^' 


(424) 


(435) 


(434) 


p  ; 


[rr"]    CtangAsln.(a' — ©')  —  tang.é'.sin.(a  —  ©')  ^ 
[rr]  '  5  tang. Ô. sin. (a" —  ©')  —  tang.â".sin.(a  —  ©')  C  ' 

Comparing  these  with  (415,416),  we  get, 

_[rr"]     (  tang.ô'.  sin. (a"  —  ©')  —  tang.ô".  sin.(a  —  ©') 
'""[77]  '  I  tang.ô.sin.(a"—  ©')  —tang.ô",  sin. (a  —  ©') 


(426)  ^  ^lîZÎ]     ^  tang.lsin.(a'  —  ©')  —  tang.ô'.  sin.(a  —  ©')  )  _ 

°      [""']  *  (  tang.ô.sin.(a"  —  @')  —  tang.ô".sin.(a  —  ©')  ^  ' 

ïrr"]  îr)-"1 

in  which  we  must  substitute  the  value  of  tlie  factors     - — ^     and     - — -.     Now  if  we  use 

[)■)•']  [rr'] 

the  abridged  symbols     A,  y^,  y^     (428,429,430),  and  suppose  the  intervals     i! —  t,  t" — t' 

to  be  equal,  or,  r'  =  2r  =  2r"  (319)  ;  we  shall  find  from  (342,  343),  that  both  these  factors 

become  equal  to     2A   (431),  and  the  values  of   \,  \,  p,  /'   (425,426,415,416)  become, 

as  in  (432,433); 

(428)  ^  =  1  —  — 3  ; 

(429)  _2    \  tang.fl'.sin.(a"  -  ©')  -  tang.ô".  sin.(a'  -  ©')  ^  _ 
^'         ■  \  tang.ô.sin.(a"  —  ©')  —  tang.ô".  sin. (a  —  ©')  3  ' 

(430)  y  =2   \  tang.ô.sin.(a'  —  ©')  —  tang.ô'. sin.(a  —  ©')  ^ 

'  ^  tang.ô.sin.(a" —  ©')  —  tang.ô".  sin. (a  —  ©')>' 


(431) 

[n-"]          [rr"] 
[r'r"]  ~"  [rr'j" 

'  =2A; 
1 

(432) 

\=A.y,; 

whence. 

p  =  '^■7i  ■  p'  ; 

(433) 

K  =  ^.7,  ; 

whence, 

p"=.3.y,.p'. 

Hence  it  appears  that  each  of  the  values  of    \,  \    (432,433)  contains  the  unknown  factor 

A=l  —  ~-  ;     which  is  an  inconvenience  that  Olbers's  method  does  not  suffer  ;  since  his 

value  of    M,     deduced  from     p"=M.i>     (29),  by  the  substitution  of    p,  p"     (432,433), 
does    not    contain    this    factor;    for    by  using    the  value  of    p,  p"     (432,433),  we   have 


P"         >= 


M  =  -=^  — .     Substituting  this  last  value  of   M,    also,     p=^.7, ./    (432),  in  (31 ,32) 

we  get  (4.36,438).     The  expression  of    r'-     (437),  is  similar  to  (31).     The  same  values 

<-^^^'     of    M,   p,    being  substituted  in  (33),  give  the  first  expression  of    c^    (439),  and  the  second 

expression    is    the    same    as    in    (403).     Lastly,    substituting    the    values    of    r^,  r'-,  r"a 

(436 — 438)  in  (414),  we  get  (440)  ;  observing  that  terms  of  the  order    t^     are  neglected 


1 


COMPUTATION  OF  THE  ORBIT  OF  A  COMET.  829 

[59941 
in  the  second  member  of  (439, 440)  ;  but   may  be  introduced,  by  noticing  the  terms  of  a 

higher  order,  wliich  are  neglected  in  (406  k.c.)  ; 

r^  =  R^  —  2.y.  .l?.^.p'.cos.(©  -  a)  +  y,^A^  p'^.sec^.é  ;  («oj 

r'^  =  R'^  —  2.R'.  p'.  cos.(©'  -  a')  +  /a.  sec^.d'  ;  («t) 

r"2  =  R"^  —  2.y,  .R".  A.p'.co5.{©"  —  a")  +  7/.  A^.p'-\  sec^ô"  ;  («e) 
'  ,-2  4-  r"3  _  2.RR". COS.  (©"  —  ©)                                   A 

J  + 1 2.y,.R".cos.{©"—  a)  +  2.y„.R.cos.{(^  —a")  I  Jl.p'  V==4.ra.  ^ 4  —  '  (  ;    P^P'^'^f'™  °'1     ''='°' 
.  +  j^— 2.7,.7,.cos.(a"— a)— 2.7,.7„.tang.é.tang.â"|.^2_/a) 

R^  —  -2.R'^  +  R"^  \ 

r-2.v,.R.cos.(©-a)+^./î'.cos.(©'-a'))  /  ,,      ,,r  -, 

+  {  '^  )  .A.f'    \_g     2)'        ^?     I     Expression  Of    I 

(  — 2.7v/î".cos.  (©"-a")  j  (  ~  ~'^  7  r~a  \  '  U-2r'2+,-"2j 

2 

is' 


+  {y?.  sec^.d—  --.sec2.4'+7,2_sec2.é"|.^a./a 


(440) 


(441) 


(442) 


Multiplying  the  equation  (440)  by  —  4,  and  adding  the  product  to  (439)  ;  after  substituting 
the  values  of  r^,  r"^  (436,  438),  we  get  the  fundamental  equation  of  Mr.  Lubbock's 
method, 

In  this  equation,  «3',  B',  C  are  functions  of  the  given  quantities  R,  R',  R',  ©,  ©',  ©", 
a,  a',  ol",  ê,6',è";  and  of  the  unknown  quantity  A  (428).  If  we  put  A=^l,  in  the  first 
operation,  we  shall  obtain  the   approximate  values  of    A',  B",  C  ;     and  then    putting 

-  =  0,     to  correspond  to  a  parabolic  orbit,  we  shall  finally  obtain  the  quadratic  equation, 

^'  +  5'./+C'.p'2  =  0;  (443) 

for  the  determination  of  an  approximate  value  of  p',  or  A.f.  With  this  value  of  p',  we 
may  find  an  approximate  value  of  r'  by  means  of  (437),  and  this  is  to  be  used  in  finding  jl 
(428).  This  last  value  of  A  must  be  substituted  in  (439,440),  in  order  to  get  a  more 
accurate  expression  of  the  equation  (441,  or  443)  ;  and  thence  a  corrected  value  of  .3.p'.  '^^"'^ 
The  same  process  is  to  be  repeated  till  the  true  value  of  Ap  is  found  ;  and  ihen  from 
(436  &1C.)  we  get  r,  r',  r",k,c.  What  we  have  said,  will  serve  to  explain  the  principle  of 
this  method,  which  is  illustrated  by  examples,  in  the  works  of  Mr.  Lubbock,  mentioned  '■'^*^'> 
at  the  commencement  of  this  article. 

VOL.  III.  208 


830  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5994] 


(446) 


(147) 


(449) 

(450) 

(451) 
(402) 


If  we  compare  these  two  methods  together,  we  shall  see  that  the  peculiar  advantage  of 
Mr.  Lubbock's  method  is,  that  the  determination  of  p'  is  reduced  to  the  solution  of  a 
quadratic  equation  (443)  ;  but  the  accuracy  of  this  equation,  is  considerably  impaired,  in 
the  first  operation,  by  putting  A=  I  (442)  ;  and  this  defect  can  be  remedied  only  by 
successive  operations,  with  repeated  solutions  of  the  quadratic  equations  after  correcting  the 

(448)  coefficients,  which  increases  the  labor  considerably,  and  sometimes  alters  very  essentially 
the  coefficients  of  the  equations,  so  that  it  changes  materially  the  successively  approximating 
values  of  p'.  This  is  evident  by  the  inspection  of  the  coefficient  of  Jî-p',  in  the  second 
and  third  lines  of  the  first  member  of  (440)  ;  where  we  see  that  when  the  interval  of  time 
is  small,  the  term  which  is  to  be  divided  by  A  is  nearly  equal  to  the  sum  of  the  other  two 
terms  of  this  coefficient,  and  has  a  different  sign  ;  so  that  the  resulting  coefficient,  arising  from 
the  difference  of  these  expressions,  is  frequently  so  small  as  to  be  materially  afl"ected  by  the 
divisor  A,  which  affects  the  largest  term  of  this  coefficient.  Similar  rermaks  may  be  made 
relative  to  the  three  terms  of  the  coefficient  of  A^.  p'~,  In  the  fourth  line  of  the  first  member 
of  the  equation  (440).  Moreover  the  intervals  between  the  observations  are  required  to  be 
equal  in  the  equation  (414)  ;  and  the  peculiar  form  of  the  second  member  of  this  equation  is 
founded  upon  this  circumstance  ;  so  that  this  method  could  not  be  applied,  without  some 

(453)  modification,  when  the  intervals  are  unequal.  Neither  of  these  objections  apply  to  the  method 
of  Dr.  Olbers,  because  the  fundamental  equations  (31,32,33),  contain  only  the  known 
coefficients  of     f>,  p^,     and  the  equations  may  be  used  whether  the  intervals  be  equal  or 

'''^''*  unequal;  the  equal  intervals  being  however  the  best.  Finally,  in  consequence  of  introducing 
the  three  radii  r,  r',  /',  into  the  equation  (414),  we  are  under  the  necessity  of  computing 
the  coefficient  of  the  equation  (437),  in  Mr.  Lubbock's  method,  as  well  as  the  value  of  A, 
neither  of  which  are  wanted  in  Dr.  Olbers's  method,  or  in  the  similar  method  of  Mr.  Ivory. 
Thus,  we  see,  that  these  methods,  which  are  the  best  now  known  by  astronomers,  have  each 

(457)  their  peculiar  advantages  and  disadvantages.  They  are  short  and  simple  in  their  application  ; 
taking  into  view  the  difficulties  of  the  problem  ;  and,  by  either  of  them,  an  astronomer  can 
obtain  the  elements  of  the  orbit,  in  a  few  hours.  Instead  of  being  employed  several  days,  or 

'*^^'     weeks,  as  in  the  early  calculations  of  the  orbits  of  comets. 


[5995]         METHOD  OF  COMPUTING  THE  ELEMENTS  OF   THE  ORBIT  OF  ANY  HEAVENLY  BODY;    THERE  BEING  GIVEN 
THE  TWO  RADII     rtVi,     THE  INCLUDED  ANGLE     v'—v  =  2f,    AND  THE  TIME    t'—t 
OF  DESCRIBING  THE  ANGLE  2/. 

This  is  a  very  Important  problem,  in  the  computation  of  the  elements  of  the  orbits  of  the 
planetary  bodies  ;    and   the   method  of  Gauss,   which   we   shall   give   in   [5999]   depends 

(1)    essentially  upon  it.     He   has   given   two  different  solutions  ;  the   one  by  the    process  of 
quadratures;  the  other,  by  developing  the  quantities  in  series,  and  reducing  them  to  tables, 

2)    as  in  Tables  VIII,  IX,  X.     We  shall  restrict  ourselves   to  this  last  method  ;  which   has 
different  forms  in  the    ellipsis,  parabola,   and   hyperbola;  and   it  is  therefore   necessary  to 

^''    consider  each  of  them  separately. 


(455) 


(456) 


ELLIPTIC  ORBIT  COMPUTED  FROM    r,  /,  v'  —  v,t'  —  t. 

TO  FIND  THE  ELEMENTS  OF  AN  ELLIPTICAL  ORBIT. 

In  the  first  place  we  shall  suppose  the  orbit  to  be  elliptical  and  shall  use  the  following 
symbols  (6 — 16)  which  are  similar  to  those  in  [5985].  For  convenience  of  reference  we 
shall  also  insert  in  the  table  (17 — 67),  most  of  the  formulas  which  are  used  in  this  method; 
and  shall  afterwards  give  the  demonstrations  in  (68&C.); 

r,  r'      the  radii  vectores  ; 

t',  v'     the  mean  anomalies  ; 

u,  u'     the  excentric  anomalies  ; 

the  semi-parameter    jJ  =  «.(1  —  e^)  =  a.cos^.p  =  b.cos.cp  ; 

a  =  the  mean  distance  ;  that  of  the  sun  from  the  earth  being  unity  ; 

6  =  the  semi-conjugate  axis  =  a.\/i—c^  =  a.cos.<p  = =  \/(ip      [5985  (5),.378??2]  ; 

e  =  the  excentricity  =  sin.ip  ;  \/i—e^  =  cos.(p ; 

-2f^v'-v;  v  =  F-f; 

2F==v'+v;  v'=F+f; 

2g=u~u;  u  =  G—g; 

2G  =  u'-\-u;  u'=G-'s-g. 

l.sin.g  =  s'm  f.\/Tr'  ; 
b.sin.G  =  sin.F.y/î'y; 
sin.y.sin.G  =  sin.o-.sin.F 
p.cos.^  =  (cos./-|-e.cos.F).\/7T'; 
p.cos.G^  |cos.i^-|"  e.cosf\.^rr'  ; 
cos  f.\/rr'  =  {cos.^  —  e.cos.G|.a  ; 
cos.F.^r7=  jcos.G  —  e.cos.^}.a; 


:  tang.  (45"' — w); 


r'  —  r  ^  2afi.sin.o-.sin.  G 


4.tang.2w 


•  V^y  ; 


cos.2w 

r"  -\-r  =  2a  —  2ae.cos.^.cos.  G  =  2a.sin^.g-  -f-  S.cos./.cos.^.^/jy  . 
^  (2  +  4.tang^  2^')  .^=  2.cos./  .(1+21).^^'; 


v/:^+v/p_, 


2.C0S/ 


+  21; 


\/'-+  \/'-,  =  (2  +  4.tang^.2«;)  ; 


/;•         4.tang.2?c 
V        r  cos.2k' 

. %\x?.\  f      tan2,-.2i<' 

cos.y  COS. y 

2.(/+  sin2.iir).cos./:v/;7 

«  = ■ ^"i '-^^■, 

s\a.  .g 


r  Assumed  I 
value  of  Mj.J 


[AssumecJ  "I 
value  of  /.J 


831 

[5995] 

(*) 

(5) 

(C) 

(7) 
(8) 

(9) 

(10) 

(11) 
(12) 
(13) 

(14) 
(15) 
(16) 

(17) 
(18) 
(19) 
(20) 

(21) 
(22) 

(23) 
(24) 

(25) 

(26) 
(27) 

(28) 


(29) 
When 
COS./   is 
positive. 

(30) 


(31) 


(35) 


832 


APPENDIX  BY  THE  TRANSLATOR  ; 


[5995]  ,_ 

^\2.{l  +  smKls:).cos.fVrr'\  , 
(33)     i/a  =  ±    -. > 

kt 
,,,,    —  =  u'  —  e.sin.w'  —  u-\-  e.sm.u  ; 

(o^J  3 


C Upper  sign,  if  sin.ff  be  positive."! 
Lower  sign,  if  sin.^  be  neg;itive.  J 


:  2g  —  Se.sin.^.cos.G  ; 
:  2g  —  s\n.2g  +  2.cos./.sin.^ 
kt 


s/rr' 


(35) 
(36) 

(37)  m  = 

2icos.y.(rr')* 

(38)  log.m^  =  5,5680729  +  2.1og.«  -  .S.log.cos/—  §.log.(7T')  ; 
^     ,    ,7   ,   ^-^.^x?  /2^  — sin.2^ 


[Assumed  "I 
value  of  ÏH.  J 


(39)    ±m=(Z  +  sin^|^f   +(Z  +  sin^|^) 


sin.^^ 


(40)     m 


(41)     a;  =  s\n.^g  =  J.(  I  —  cos.^)  =  J  versed  sin.^  ; 
2g  —  sin.2^ 


(42)       X==  ■ 


CLTpper  sign,  if  sin.^  be  positive.  "I 
Lower  sign,  if  sin.^"  be  negative.  J 


[Used  when  sine    g    and "! 
cosine    /    are  positive.  J 

[Assumed   "I 
value  of   I.J 

Assumed 


sin.^jg' 


(43)  I  =  a;  —  f  -t-  7-^  = 

(44)  y    —        I     J^ 

(45)  A  = 

(46)  h  ^ 


■m  sin.^g  — ^.(2g--sin2g).(l— |.sin.%) 

9X 


ft.(2^— sin.2^) 


m 


-Ma;— I)         v/i  +  x' 


}»•-= 


i  +  Hl' 


(47)       X    =     -5    /  . 

yi 


\/r+l/i^ 


(48) 

When 
COS./    is 
negative. 

(49) 


2. COS. y 


=  1— 2L; 


_  sin. 2*/        tang.22ît) 


(50)      -'"  3 


COS./" 

kt 


COS./      ' 


2^.  (— cos./)*.(rr')* 

—  2.(1,  —  sin.%).cos./:i/;y 
(51)    a   =  - 


sin.^^ 


(52) 


±  M=-(i^sin.%f +(^sin.2ig) 


„     ,H-   /  2p- — sin.2p- 


sin.^^ 


[Assumed    T 
value  of    X.J 

C   Assumed     "I 
value  of    à. J 

[Assumed    "1 
value  of    y.  J 

C  Assumed   "1 
value  oi    /i.J 


[Assumed  l 
value  of  L.\ 


[Assumed     "1 
value  of    J/.  J 


ELLIPTIC  ORBIT  COMPUTED  FROM     r,  /,  v' —  v,  f —  t. 


M=-iL  -,r  )*+  ,!^JSL.  =  "^VL^^  ; 


r  =  -  1  + 


4 i5-('» 1) 

L  —  x  M 


i-?û-(*-|)        K^L-x' 


H  = 

H  = 


M2 


(Y+l).Y^ 


T       ^^' 
X    =   Li ; 

m^  cos./i/;y 
!/-      sia-'.sr 


a  =-2. 


3P  CQS.fYrr'  . 


sin-.^- 


/)/.rr'.sin.2/"\^ 


27  = 


Y.rr'.s\n.2f\^ 


log./.-  =  8,2355814 ....      [5987  (8)]  ; 

log.fc  in  seconds  =  3,55000657  ....      [5987  (14)]  ; 

with    a,p,    we  get     cos.p  =  \/l  — ea=  \//  -;      (H); 

^      co3.^      \/7P.cos.f  v/;7 

COS.  u  = •  =  cos.fi".cosec.(p cos.f.cosec.ffl  ; 

e  ae  '^  ^         a         •'  - 

.  sin./sin.G  . 

sin.!*  :=: -. =  sin./.sin.Cr.cosec.e'  ; 

sin.o- 

o 

mean  daily  motion     ^  ka    '';     or, 

log.  mean  daily  motion  in  seconds     =  3,55000657  —  f  log. a. 

Other  formulas  of  a  similarnature  may  be  deduced  from  these,  particularly  the  expressions  of 

sin.(|/q=^o-);         cos.(J/zfJ-);         sin.QFqrJG);         co%.{\F ^\G)  ; 

which  may  be  conveniently  used  in  logarithmic  computations.  In  general,  however,  the  use 
of  these  auxiliary  angles  requires  more  labor  than  the  common  processes  of  spherical 
trigonometry  ;  and  the  formulas  we  have  given  are  all  that  are  necessary.  We  shall  now 
proceed  to  tlie  demonstration  of  these  formulas  (17 — 67). 

If  we  select  the  last  values  of  sin.iw,  cos.iw  [5935(12,13)],  and  then  accent  the  symbols 
r,  »,  M,  we  shall  get  the  corresponding  values  of  sin.|w',  cos.|m'  ;  substituting  these  in 
the  first  member  of  (69),  it  becomes  as  in  its  second  member  ; 

VOL.   III.  209 


833 

[5995] 

(53) 


r  Assumed     "1 
Lvalue  of    r.J 

(54) 

r    Assumed     1 
Lvalue  of    //.J 

(55) 

(50) 

(57) 

(58) 

(59) 

(60) 

(61) 

(62) 

(63) 

(6t) 

(65) 

(66) 

(66') 
(67) 


(07) 


(66) 


834  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5995] 

\  TT  § 

(69)     sin4w'-cos.jM  =Fcos.iM'-sln.iM=  \  -^r; ^f  ^'   ^sin.iw'-cos.JrTcos.lD'.sm.J^K 

(«''.(1 — e-))  ^ 

Multiplying  this  by  h  =  «.(1  — (?)'"  (H),  and  reducing,  by  means  of  [21,22]  Int.  we 
get, 

(TO)  J.sin.J.(H'  =F  m)  =  (?•;•')*.  sin.|.(i;'  ^  v)  ; 

substituting  the  values  (13 — 16)  we  get  (17,18);  the  upper  sign  giving  (17),  the  lower, 
(18).  Multiplying  crosswise  ihe  two  equations  (17, 18),  and  dividing  by  h.\/^',  we  get 
(19).  In  like  manner,  if  we  substitute  the  third  values  of  [5985(12,13)],  in  the  first  member 
of  (71),  we  obtain  its  second  form,  and  by  connecting  together  the  teims  depending  on  e, 
and  reducing,  by  means  of  [23,24]  Int.  we  get  (72), 

('1)    jj.{cos.|m'.  Cos.^M±sin.|M'.sin.jM|  =  {(l  -\- e).ç,o=,.^vi' .co?,.\xi  ^^{X  — t).%\a.\v  .•sm.\v\.\y'Çp 

C  (cos.|«'.cos.J«  ± sin.it)'.  sin. Jîj)         ^ 
C  -\-t.{co'S,.^X!' .CQ?,.\v:::ç.'^m.\v' ,%\x\.\v)'  ) 
C'a)  p.cos.(^M' q: ^m)  =  {cos.(jî)'q=  J«)  -|- e.cos.(J.w'± l'v)\.  \  tt-' 

Substituting  (13 — 16),  we  find  that  the  upper  sign  of  this  last  expression  gives  (20),  the 
?ower  (21).     Multiplying  (21)  by     — e,   and  adding  the  product  to  (20),  we  get, 

(73)  p.{cos.^  —  c.cos.G}  =  \/r7.(l  —  e^).cos./; 

substituting  p=ia.(l — e^)  (9),  and  dividing  by  1  —  c^  we  get  (22).  In  like  manner, 
if  we  multiply  (20)  by   —  c,  and  add  the  product  to  (21),  we  get, 

(74)  p.  I  cos. G  —  e.cos.^l  =^,y".  (1  —  e2).cos.F; 
substituting  the  same  value  of    p,  and  dividing  by     1  — e^     we  obtain  (23). 


(75) 

(76) 
(77) 


(78) 


(79) 


We  have,in  [5985(9)],     j-=a.(l  — e.cos.tj),    r'  =  a.(l  — c.cos.m')  ;     taking  the  sum, 
and  the  difl^erence  of  these  quantities,  we  get,  by  means  of  [27,28]  Int., 

r —  r=  ae.^cos.tt  —  cos.?(' j  =  2ae.sin.^.(2/4"")'S'n'2-("'  —  ")  '■> 
r'  -|-  r=2a  —  ae.^cos.?t'-j- cos.î<}=2a —  2ae.cos.^.(u'  -\-u).cos.i.{u'  —  u)  ; 

substituting  the  values  (15,16),  we  obtain  the  first  forms  of  the  values  of  r' — r,  r'-{-r 
(25,26).  The  second  expression  (26),  is  deduced  from  the  first,  by  changing  the  term  2ft 
into  2rt.(sin^.^-l-cos^.^),     by  which  means  we  obtain, 

r'-\-r=  2a.sin^.^  4-^cos.^ — e.cos.G  j  .«.2. cos.  g=^  2fif.sin2.^-|-^cos./.;/^|  .2.cos.^     (22). 

These    admit   of  further    reductions,    by  the    introduction   of  the    symbol    w    (24)  ;  and 

if  we  put  for  a  moment   45''-[-  w  =  w,     we  shall  have      \    /^ '- ^  tang-,  w  ;     substituting 

this  in  the  first  member  of  (SO),  and  successively  reducing,  by  means  of  [34', 32, 31]  Int., 
we  finally  get  the  expression  (81),  which  is  the  same  as  (29), 


ELLIPTIC  ORBIT  COMPUTED  FROM     r,  r',  v'  —  v,  t' —  t.  835 

[5995] 
\    /^^-f  \/-=  tang^.w -f  cotan^w  =  2  +  {tang.w  —  cotan.wp 

Csin.w        cos.w)^  ,    Csin^.w — cos^.w)      ^,  ( — cos.2vv)2 

=  2+< ; [  =2+]—^ [=2+K   •    o     ( 

^cos.w       sin.w)  (     sin.w.cos.w     )  (  t.sin.aw  ) 

=  2+{— 2.cotan.2w|2  =  2+4.tang^2w. 


(80) 


(81) 


Multiplying  this  last  expression  by     \/'n',     we  obtain  tlie  first  value  in  (27);    finally,  if  we 
multiply  the  assumed  value  of    1+2/   (28),  by    2.v/r7.  cos./,     we  shall  get  the  second 
expression  in  (27)  ;  and,  we  may  incidentally  observe,  that  the  comparison  of  (28)  with  (81)     (Si) 
evidently  shows  that   I  is  positive.     The  same  expression  (79),  gives. 


/             yr                                           sin-.w      cos^.w 
-,  =  tan2:-.w  —  cot-.w  =  — ~^—i — ■ 


(82) 


r        \/      r  cos-.w       sin'.w 

the  numerator  of  this  expression  is  easily  reduced  to  the  form, 

(sin^.w  -(-cos^.w).(sin-.w  — cos^.w)  =  sin^.w  —  cos^.w  =  —  cos.2w  =  sin.2w;  (gg.j 

and  the  denominator  is, 

(sin.w.cos.w)^  =  (^.sin.2w)^  =  (j.cos.2w)^  =  J.cos^.2««  ;  (82,, 

hence  we  easily  deduce  the  expression  (30).  Multiplying  this  by  \/r7,  we  obtain  the 
second  form  of  (25).  From  the  assumed  value  of  1  +2/  (28),  we  get,  by  substituting 
(81),  the  first  expression  of  I  (83)  ;  reducing  by  means  of  [1]  Int.,  we  get  the  last  form 
in  (83),  which  is  the  same  as  (31),  and  is  composed  of  the  given  quantities    /,  w, 

2+4.tang^.2w  1 — cos/      tang^.2i«      sin^.j/       tang^.2(f 

4.CO3/  ^  2.C0s/      '  cos./  cos/  COS./  (^3) 

Transposing  the  last  term  of  the  second  expression  (26),  and  dividing  by  2.sin^.^,  we 
get  successively,  by  using  the  last  of  the  formulas  (27)  ; 

r-}-/ — 2. COS./. COS.  fC-\/rP       2.cos./.(l  +2Z).\/^ — 2.cos./.cos.^.\/r7 
"  ^  2.sin2.^  "^  2.sin2.^  <^^' 

_  J2?+l— cos.g}.2.cos.//,~       I  2?4-2.sin^.ig  } .^.cos.f.s/^' 

'H.sm^.g  ~  a.sin^.^-  "  (85) 

This  last  expression  is  easily  reduced  to  the  form  (32)  ;  and  its  square  root  is  as  in  (33)  ; 

to  which  the  double  sign  ±  is   prefixed,  so  that     ^'  +  sm'J.lg  yl  +  x     u\\    JJ^f^y 

siu.g  sin.g-        »      ■"        •? 

be  considered  as  a  positive  quantity. 


(85') 


Substituting   n  [5987(12)]  in  [5985(7)],  and   neglecting  the  mass  m,  on  account  of  its 
smallness,  we  get  the  first  formula  (87)  ;  the  second  is  deduced  from  the  first,  by  accenting    (sg) 


836  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5995] 


ht  .  kl' 

3 


(87)  —  =  M  —  e.sin.M  ;  — =  ii  —  e.sin.M'. 


(88) 


(89) 


Subtracting  the  fii-st  of  these  expressions  from  the  second,  and  for  t' —  i,  which  represents 
the  interval  of  time  between  the  observations,  putting  simply  t,  we  get  the  expression  (34). 
This  is  easily  reduced  to  the  form  (35)  by  substituting     u'  —  ii^2g  (15),  and, 

sin.?*' —  sin.M  =  2.sin.(2-M'  —  ^u).CQS.[iu' -\-  iu)  =  S.sin.^.cos. fr     (15, 16)  ; 

but  from  (22),  we  have, 

„  ^    yrr' 

(90)  e.cos.  Cr  =  cos.^  —  cos./ . ; 

substituting  this  in  (35),  and  putting  2.sin.^.  cos.^  =  sin.2^,  it  becomes  as  in  (36).  The 
symbol  m  (37),  is  used  for  brevity,  and  when  cos./  is  positive,  the  expression  of  m, 
(90')  will  be  a  real  and  positive  quantity  ;  being  a  function  of  the  given  quantities  r,  r  f,  t,  k; 
and  its  equivalent  logarithmic  expression  is  given  in  (38)  ;  using  the  value  of  log.fc 
[5987(8)].     Multiplying  (37)  by  the  denominator  of  its  second  member,  we  get, 

3  3  ?. 

(91)  kt  =  m.2  - .  cos.  ^/.  (  rr')  *  ; 
substituting  this  in  (36),  and  then  multiplying  by     a^,     we  obtain, 

3  3  3  3  X       i 

(92)  m.2"^\  cos.V-  {rr'f  —  (2o'  —  sm.'2g).cfl  +  2.cos./.  sin.^.  (  rr'y.a^. 

Using  the  value  of    i/a     (33),  we  find  that  each  term  of  the  expression  contains  the  factor 

3.  3 

cos.^/.(rr')*,     and  by  rejecting  it,  we  get, 

(93)  m.22  =  -i-  (2^  —  sin.2g) .  ^   '^      .  ^   "'^'  '    ±  2.  j  2.(;  +  sin^.iç)  |  ^  ; 

sin  .g 

3 

dividing  this  by  ±2^,  we  get  the  expression  of  ±  m  (39)  ;  the  order  of  the  terms 
being  changed.  This  equation  contains  the  known  quantities  I,  m  ;  and  from  it  we  may 
determine  the  unknoion  quantity    g.     In  the  case  which  most  frequently  occurs,   g    is  so 

y  p»  ^-^  sin  2  o* 

(94)  small  that  the  common  tables  of  logarithms  do  not  give  the  factor     .  g  '  °=  X    (42), 

with  a  sufficient  degree  of  accuracy.  In  this  case,  we  must  develop  it,  in  a  series,  ascending 
according  to  the  powers  of    sin.-Jg'  ;     and  then  the  value  of  the  factor,  which  is  represented 

(95)  by  the  assumed  symbol     X,     can  be  obtained  with  accuracy,  in  the  following  manner. 

Changing     y     into     sin.|^^     in  [4G]  Int.  we  get  the  value  of  the  arc     ^g,     in  terms  of 

(96)  sin.lg-  ;  multiplying  this  by  4,  we  get  the  expression  of    2g     (98).     Moreover, 

(97)  sin. 2^  =  2.sin.^.cos.^  ;      sin.^  =  2.s'm.ig.cos.ig  ;     cos.g  =1  —  2.sm.'^ig  ;         hence, 


ELLIPTIC  ORBIT  COMPUTED  FROM     r,  r',  v'—v,  i—t.  837 

r5995 1 
sin.2^  =  4.sin4^.(l  —  2.  sin.^ |^).cos.^g-  ;  ^^^.^ 

and  since, 

cos%=  (1  —  sin.2|o-)i  =  1  _  l.sin.21^  —  |.sin.''i^  —  &c., 

we  find,  that     sin. 2^    becomes  as  in  (99)  ;  subtracting  this  from  (98),  we  get     2g — sin. 2^ 
(100),  being  tlie  numerator  of  the  value  of    X    (94), 

2g  =  4.sin.è^  +  î.sm?^g  +  i'o.sin.^^^  +  &c.  ;  (»8) 

sin.2^  =  4.sin.^^  —  lO.sin.^io-  -}-  i-sm.^g  —  &c.  ;  ''^' 

2§-  —  sin.2^  =  f  .sin.3^^  —  f§.siu.%  —  8ic.  =  f  .sin.'Jg  .{ 1  —  ?^-^m?ig  —  &c.|.        (loo) 
The  denominator  of    X     (94)  is, 

sin.'^  =  (2.sin.^^.cos. Jo-)^  =  S.sin.^^^ .\l  —  ^sm.^^g  —  Sic {  ;  (loi) 

dividing  the  expression  of  the  numerator  (100),  by  that  of  the  denominator  (101),  we  get, 

X=  ê-M+f-sin.^i5-+  &ic.p  (102) 

expressed  in  a  series  ascending  according  to  the  powers  of    sin.^^^  =  a;     (41).     To  obtain 
the  law  of  this  series,  we  shall  resume  the  expression  of    X     (94),  which  gives, 

X.  sin.^^  =  2^'-  —  sin. 2^.  (io3) 

Taking  its  differential,  and  dividing  by     ilg ,     we  obtain, 

—  .sin.'o-  -{-  SX.sin.'^o-.cos.^  =  2  —  2.cos.2g=:  4.sin.^^.  (lo-i) 

The  differential  of    x  =  sin.^^^     (41),  gives, 

dx  =  dg  .%m,^g  COS. ^g  =  \dg.5ia. g ,     or     dg  =  -. —  ;  (ws) 

substituting  this  in  (104),  and  dividing  by     ^.sin.^g,     we  obtain, 

dX  _  &  —  G  X. cos.^  (105') 

dx  sin.*^ 

but,  from  (41),  we  get, 

cos.g-=  1 — 2x;     sin.^^- =  1 — cos.^^  =  I — (1 — 2a?)^:=4a;  —  4x^;  ^loe) 

substituting  these  in  (IDS'),  and  multiplying  by     2x —  2xx,     we  finally  obtain, 


(I—  x).2x.~  =  4— 3.(1— 2a;). X. 

Now  if  we  assume  for  X,  an  expression  of  the  form  (108),  c, ,  f, ,  &ic.,  being 
constant;  we  shall  find,  that  its  differential,  divided  by  dx,  will  become  as  in  (109). 
Substituting  these  in  (107),  we  get  (HO)  ; 

VOL.  111.  210 


(107) 


838  APPENDIX,  BY  THE  TRANSLATOR  ; 


[5995] 

(10 


(109) 


(110) 


^^=^.\c,-\-2c,.x+3c,.x"-+4c,.x^+^c.\; 

=  (8  — 4c,)..x  +  {8c,—4c,).x'^+  {Sc,  —  4c,).x''+  &tc. 
Putting  the  coefficients  of  the  different  powers  of  a;  equal  to  nothing,  we  get,  successively, 

(111)  c,  =  f;         r,=  f.c,;         c^^'^.f^;         c^  =  ^.c,k.c.; 

the  law  of  continuation  being  manifest  ;  substituting  these  in  (108),  we  finally  obtain, 

4.6  4.6.8      „      4.6.8.10      ,,    4.6.8.10.12 

(112)  X  =  4  +  .X  +  ■ • .  x^4- ■ .  x^-\ .  x'^ 4-  Sic. 

""^3.5        ^3.5.7        ^3.5.7.9         ^3.5.7.9.11         ^ 

This  value  of  X  may  be  computed  by  means  of  a  table,  with  the  argument  x;  but  it  is 
much  more  convenient  to  find  and  use  the  small  quantity  |  (43),  of  the  order  x^  (115); 
or  of  the  fourth  order  in  g,  instead  of  X  (112),  which  contains  terms  of  the  order 
X.     If  we  divide  the  fraction 'I ,  by  the  expression  of     X     (112),  we  shall  get, 


(113) 


(114)  •— .  =  f  —  a:  +  |3.a;2  +  ,%2j.a;3  4-  Sic.; 

9  X 

substituting  this  in  the  assumed  form  of    |     (43),  namely,     |  =  x — t  ~t"  tT^  5     we  get, 

(115)  |  =  #5.a;2_j-A2__3;3_j_gjc. 

With  this  formula  we  may  compute  the  values  of    | ,     as  in  table  IX,  for  the  small  values 
of    X,     when  the  usual  tables  would  not  be    sufficiently  accurate.     The  numbers  in  this 

(116)  table  are  given  for  the  values  of    x,     from     x  =  0,001,     to     a;  ==  0,300.     This  last 
(iiT)     value  corresponds  to     ^=66'' 25'";     and    for  greater  values,  if  any  should    occur  in 

practice,  we  may  use  the  indirect  method  of  solving  the  equation  (39),  in  its  present 
form  without  making  any  reduction  ;  assuming  a  value  of  g,  and  repeating  the  process, 
till  we  obtain  an  expression  which  will  satisfy  that  equation.  From  the  first  expression  of 
I  (43),  we  easily  deduce  the  second  value  of  X  (42).  Finally,  if  we  substitute  the 
assumed  value  of  X  (94),  in  the  first  value  of  |  (43),  it  becomes  successively,  by 
using     «     (41), 

sin. 2^ 


(118) 


(119) 


^'-i  +  i"-  ^ -^Z  =  si"-' J5—  *  + 


'''°^  ^~  ^'^^■2g-sm.2g-     '^        «    '    ,|.(2^-sin.2g) 

and  this  last  expression  is  easily  reduced  to  the  second  form  in  (43). 


(121) 


In  the  case  now  under  consideration,     sin.^     is  positive  ;  so  that  we  must  use  the  upper 
sign  of  the  value  of    m     (39)  ;  and  by  substituting    sin.^^^  =  a?     (41);  also  the  second 


ELLIPTIC  ORBIT  COMPUTED  FROM     r,  r',  v'—v,  t'—t.  839 

[5995] 
value  of    X    (42),     it  becomes  as  in  the  first  expression  of    m     (40)  ;  the   second   form 

is  deduced  from  the  first,  by  the  substitution  of  tlie  first  assumed  vahie  of    y     (44).     The     *'"' 

second  form    y    (44),  is  easily  deduced  from  the  second  expression  of    m    (40).    Squaring 

this,  we  get, 

/  +  1-  =  —  ;         whence,         a;  =  -  —  Z    as  in  (47)  ;  (,23, 

and  if  we  use  the  assumed  value  of    h     (45),  which  gives, 


f  +  ^  +  I  =  -7-  ;  <i23) 


we  shall  get  successively, 


4 


-  ,V(^- 1)  =  ,V(|  - ^  +  1)  =  ,« .  (1  +  ?  + 1-'^)  = ,? .^^'_^J 


(124) 


(125) 


_    9m^      (î/2  ^ 

""  10^2  •  ^  X  —  1  ^  • 

Substituting  this,  and     /  +  x     (123),  in  the  first  expression  of    y     (44),  we  obtain, 
y=l+-y^;  or,  (y_l).?^_(y_])^V^ 

whence  we  easily  deduce  the  expression  of    k     (46). 

When  the  heliocentric  motion  is  between  ISC'  and  360''  ;  or  generally  when  cos./  is 
negative,  the  value  of  m  deduced  from  (37)  becomes  imaginary,  and  I  (31)  is  negative. 
To  avoid  this  we  must  change, 

I  into  — L;      m    into    — I\l.\/ — 1     or     M.{ — 1)- ;       y  into  — 1,  and  h  into    H; 

by  this  means,  we  find  that  (28)  changes   into  (43)  ;  (31)  into  (49)  ;   (37)  into  (50),  after 

dividing  by  (  —  1)^;  (32)  into  (51)  ;  (39)  into  (52),  after  dividing  by  (  —  I  )'^  ;  (40) 
into  (53),  divided  in  the  same  manner  ;  (44)  into  (54),  after  dividing  by  —  1  ;  (45)  into 
(55),  changing  the  signs  of  the  numerator  and  denominator  ;  (46)  into  (56),  with  the  same 
changes  of  the  signs  ;  lastly,  (47)  into  (57). 

To  determine  the  value  of  y,  or  rather  of  hg.yy,  from  the  cubic  equation  (46),  a 
table  was  computed  by  Gauss,  being  the  same  as  Table  VIII,  of  the  present  collection.  (120) 
This  table  answers  also  for  computing  log.  FF  from  H,  as  is  evident  from  the 
consideration,  that  if  we  change  y  into  — F,  yy  changes  into  YY,  the  equation  (46)  for  finding 
y,  changes  into  that  in  (56)  for  finding  F,  and  log.yy  changes  into  log.  YY.  This  table 
is  calculated  from  A  =  0,  to  h  =  0,6.  From  0  to  0,04  the  intervals  in  the  values  of  h  are  „.,, 
taken  equal  to  0,0001,  which  do  not  require  the  use  of  second  differences  :  and  this  is  by 


(120) 


(127) 


(128) 


(134) 


(135) 


S40  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5995] 

far  the  most  important  part  of  the  table  ;  from  0,04  to  0,60  the  intervals  are  0,001,  and  then 

(132)  it  is  necessary  to  notice  the  second  differences,  if  we  wish  to  have  the  logarithms  correct  in 
the  last  figure  of  the  decimals.     If    /(     exceed   the  limit  of  the  table,  we  may  obtain  the 

(133)  solution  of  the  cubic  equation  (46  or  56),  by  any  indirect  process,  or  by  some  one  of  the 
well  known  methods  of  solution. 

The  values  of    /,  ?n,  h     (31,37,45)  are  positive  ;  and  as  it  is  supposed  in  the  equations 

(49,50)  that    cos./    is  negative,  (126),  we  shall  also  have  Zr  and  Jl/ positive.     We  have, 

by  [32]  Int.     — sin^.^=  cos./— cos^.i/;     substituting  this   in  the  value  of    L  (49)  it 

,  r  ,     ,      cosS.l/       ,     tançr2.2j«  ,  ,  ...  ,    „   , 

becomes     L,  =  I  -\- -f-  - — ^ — -  ;     and  as  each  term  is  positive,  we  shall  have 

(  —  cos/)         (—cos/)  ' 

L]>1;     therefore     H     (55)   is    also  positive,    |   being  small  (1 15  &.c.)  ;    moreover  as 

(136)  "*>     v'i+i   (90',  85')  are  positive,  we  shall  have   y  =: —t=^      (44)  positive;  and  for  similar 

(137)  reasons     Y^     . —      (54)   is  positive.     If  we   now  trace    the    successive  values  of    h, 

Y  L — X 

while     y     decreases    from    co    positive,  to   0,   we  shall  see,  by  the  mere   inspection  of  the 

(138)  second  member  of  the  formula  (46),  that  h  decreases  with  y  ;  becomes  0,  when 
y  =  1  ;  and  is  negative,  when  y  falls  between  1  and  0  ;  so  that  there  is  always  one 
positive  value  of  y,  which  exceeds  1,  and  will  satisfy  the  equation  (46),  for  any  positive 
value  of  /(,  from  h  =  0,  to  h  =  œ.  In  like  manner,  by  the  inspection  of  the  equation 
(56),  we  find  that  while      Y    decreases  from      co     positive  to      Y  =  ^,    H     will  remain 

'"^'     positive  ;  and  that   it  will  become  negative  when      Y    falls  between  0  and  |  ;  so  that  we 

(142)    have  always  one  positive  value  of     Y,     which  exceeds  i,  and  satisfies  the  equntion  (56), 

for  all  positive  values  of  H.   from    II z=  co,    to  its  least  limit.     After  tliis  digression  on  the 

nature  of  the  roots  of  the  equations  (46,56),  we  shall  now  proceed  to  the  explanation  of  the 

'^■*^'     manner  in  which  these  roots  are  obtained  by  approximation. 

If  I  be  known  we  shall  have  the  value  of  h  (45)  or  H  (55)  ;  and  then  from  the  cubic 
(145)  equation  (46  or  56)  we  can  obtain  y,  or  Y;  and  finally,  from  (47  or  57),  the  value  of 
(140)     X.     Now  as  I  is  a  very  small  quantity  of  the   fourth  order  in    g    (113),  wc  may  at  first 

(147)     neglect  it  in  the  values  of   h  or  jH  (45  or  55),  putting     h=  g-^r,  ,     or   11=  '      5  . 

With  this  value  of  h  or  II,  we  find,  from  Table  VIII,  the  corresponding  value  ijf  log.  yy, 
or  log.YY;  whence  we  obtain,  from  (47  or  57)  the  value  of  x,  and  with  this  we  get, 
in  Table  IX,  the   corresponding  value  of    |.     Having  obtained    |,  we  may  repeat  the 

(]49)  calculation,  using  (45  or  55),  to  obtain  a  corrected  value  of  x  ;  and  generally,  one  operation 
will  be  sufficient  to  get  the  true  result.  Having  found  x,  we  get  g  from  the  equation 
(41),  T  =  sin^.50',  or  versed  sine  g=2x.  Wc  may  here  remark,  that  both  of  the  angles 
u'  —  u  =  2g,     and     v'  —  v=2f,     (13,15)  fall  between  0'' and  360'';  or  between  the 

(151)  same  multiples  of  360'' ;  consequently  the  angles  g,f,  fall  between  the  same  multiples 
of  180". 


(139) 
(140) 


ELLIPTIC  ORBIT  COMPUTED  FROM    ,-,  /  v'—v,  t' —  t.  841 

.  [5995] 

Now  considering    g     as  a  known  quantity,  loe  shall  •proceed  in  the  investigation  of  the 

formulas  (58 — 61),  for  the  determination  of  the  elements  of  the  orbit.     We  have,  from  the     (152) 
equations  (-10,41)     / -|-  r  =  ? -(- sui". Jo- =  — ;    substituting  this  expression  of  /-j-sin^.|^, 
in  (32),  we  get  the  value  of    a     (58).     In  hive  manner,  from  (53,41),  we  have, 

L-X=L-  S.n^.  k  =    yâ  ;  (154, 

substituting  this  in  (51),  we  get  the  value  of  a  (59).  Dividing  the  square  of  the  equation 
(17)  by  the  expression  of  a  (58),  and  rejecting  the  factor  sln^.  ^,  which  occurs  in  both 
members  of  the  equation,  we  get  the  first  expression  (155).  Substituting  the  value  of  m^ 
(37),  we  get  its  second  form  ;  and  the  third  form  is  easily  deduced  from  this,  by  using 
2. sin./,  cos,/  =  sin. 2/; 


(155) 


J2  _  >/.  s\n^.  f(rr')i      y=^.(n-')3.(2.sin./.cos/)2  _  C  y.>T'.sin.2/  )  2 
a    ~~       2m9.cos./     ~"  kH^  ~  (         kt         \     ' 

52 

now  we   have     -  =jj    (H)  ;  hence  we  get  the  expression  of    p  (60).     In  like  manner, 

fit  (  1 5(i  ) 

by  squaring  the  equation  (17),  then  dividing  by  the  expression  of    a  (59),  and  substituting 
JIP    (50),  we  get  (61).     Now  if  a  planet  revolve  about  the  sun,  in  a  circular  orbit,  at  the 

distance  a;  the  angular  motion  in  the  time  t  will  be  represented  by  nt  =^  —  [5987(12)1, 

neglecting  the  mass  of  the  planet,  on  account  of  its  smallness.     Multiplying  this  by    ^a^, 
we  get  the  area  of  the  circular  sector     ^.\/a.kt,     described  by  the  radius  vector,  in  the  time     (isg) 
t,  in  this  circular  orbit,  whose   mean  distance,  or  semi-parameter  is    a.     If  we  retain  the 
same  mean  distance,  and  suppose  the  orbit  to  be  an  ellipsis,  whose  semi-parameter  is  p  (9),     ''^^' 
the  area  described  by  the  radius  vector,  will  be  decreased  in  the  ratio  of  the  square  roots  of 
the   parameters  of    s/p     to     \/a  [383"],  and  it  will  therefore  become     l-s/p.kt  (158)  ; 
which  may  represent  in  figure  84,  page  792,  the  area  of  the  sector  sab;  included  between 
the  radii     Sa=^r,Sb  =  r',     and  the  elliptic  arc  a?i.     On  the  other  hand,  the  area  of  the     '"^'' 
triangle    Snb,    included   between   the  radii     .S'a  =:  r,     Sb  =  r",    and    the    chord    ah 
represented,  in  [5994(300')],  by 


(ICO) 


(162) 


(163) 


^.[jr]  =  ir/.  sin.(î;'  —  ■!;)  =  ^rr' .  sin.2/  (13). 

Dividing  the  area  of  the  sector  (160),  by  that  of  the  triangle  (163),  we  obtain  the  ratio  of 
these  two  areas  as  in  the  first  of  the  following  expressions  ;  and   by  comparing  it  with  the 
value  of    y,    deduced  from  (60),  or  that  of    Y    from    (61);  we  find  that  they  are  equal    C^^') 
to  each  other,  as  in  the  third  and  fourth  expressions  (164)  ; 

area  of  the  sector  sah  ^.\/p.kt 

area  of  the  triangle  506  ^r7-'.s\n.2f  Ci64) 

VOL.   III.  211 


842  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5995] 


(165) 


(165') 


()66) 


(168) 


(172) 

(173) 
(174) 


(175) 


Hence  it  appears  that     y     or     Y    represents  the  ratio  of  the  area  of  the  elliptical  sector 
sail,  to  that  of  the  triangle  sab.     If  we  substitute, 

m 

V//  +  s,n2.àff  =  /r+T=-     (41,40), 

and  X  (42)  in  (39),  we   get  the  expression  of    m    (168),  corresponding   to   figure   84, 
page  792  ;    sin.^   being  supposed  positive.     In  like  manner,  if  we  substitute, 

M 


(167)  \/i,— sin^.Ag-  =:  \/L  —  ,r  =  —        (53), 

in  (52),  we  get  the  value  of    M  (169),  corresponding  to   sin.^    positive, 


m  =  --{-  —.X . 

y     y^      ■ 


(169)  M  = .X. 

Y    '^   y3 

Now  if  we  suppose  the  quantity  ?«,  which  is  proportional  to  the  time  t  (37),  to  represent 
the  area  of  the  sector  sab  ;  the  quantity     —     (164),  will  represent  the  area  of  the  triangle 

(170)  ^ 

sab  (164)  ;  and  their  difference,  which  is     — ;•  X     (168),  will  therefore  represent  the  area 

of  the  segment,  included  betW'Cen  the  chord    «6,  and  the  elliptic  arc  ab.     Similar  remarks 

"^''    may  be  made  relative  to  M  (169),  observing  that  when  the   angle     bsa     exceeds    ISO'', 

we  have  the  sector  equal  to  the  difference  between  the  segments  and  the  triangle.     Hence 

1  3    X 

it  is  manifest  that  the  quantities     m,  (Z  -f  xy,     (I  -\-  x)" .—,     in  the  equation  (39  or  40)  ; 

1  ?  X    . 

and  the  quantities     M,  {L  —  x)''^,    (L  —  *)"'T^  in  (52or  53),  are  respectively  proportional 

to  the  sector,  the  triangle,  and  the  segment  ;  and  these  geometrical  considerations  serve  very 
much  to  illustrate  this  part  of  the  calculation.  We  shall  now  show  the  use  of  these  formulas, 
by  the  following  examples,  given  by  Gauss. 


EXAMPLE     I. 

Given,  log.r  =  0,1394892,  log.r' =  0,3978794,  «' — «  =  5/=  224»',  i  =  206  ^^',80919;  to  find  the 
elements  of  the  orbit  a,  p,  e  ;  the  true  anomalies  v,  v'  ;  and  the  excentric  anomalies  u,  u'.  In  this  example, 
the  value  of  Y  exceeds  the  limits  of  Table  VIII  ;  we  must,  therefore,  in  this  case,  deduce  V  from  the 
original  cubic  equation  (56),  instead  of  using  that  table.  We  have  computed  G,  in  (i8i),  by  the  formula  (65)  ; 
we  may  also  determine  sin.G  by  (25);  and  we  find,  from  these  formulas,  that  sin.  G  and  cos.G,  are 
positive,  therefore  G  (182),  falls  in  the  first  quadrant  of  the  circle,  [5990,  (23,  24)].  In  like  manner,  we  have 
computed  sin.  F  (iS3)  from  (66)  ;  we  may  also  compute  cos.i^  from  (23),  and  as  both  expressions  are  positive, 
F  must  also  fall  in  the  first  quadrant. 


ELLIPTIC  ORBIT  COMPUTED  FROM     r,  r',  v'  —  v,i'  —  t. 


To  find    X. 
t'    log.    0,3978794 
r     log.    0,1394892 


^  tangl.(45''-|-!t')  log.  0,2583902 


45<q.„-_4g'']4'"43;-8  tang.  0,0645975 
w!  =  4''i4'"43',78 


0,3978794 
0,1394892 

sum     0,5373686 
half    0,2686843 


2«j=8''  29™  27^,56 


tang9.2i/j 


cos.f 

f=   II2<f 

è/=    56* 

sin2.  if 

COS./ 


=   0,0594959 


=  1,8347335 


(ir)^log  0,8060529 

ar.co.  9,1939471 

tang.  9,i74o3i4 

same  9,17403 14 

ar.co.cos.  0,4264246» 

log.  8,7744874» 

ar.co.cos.  0,4264246» 

sine  9,9185742 

same  9,9185742 

log.  0,2635730» 


sum  is     L  =  1,8942294 
^  =  0.8333333 

L  —  |-  =  1,0608961 
MM    (176) 

Approx.  H 

Hence  from  the  cubic  >  ,  •      ,     xr  I      TT' 

equation  (56),  we  get  J  APP"^"^="«   ^    =     '.591432 


log.  0,0256728 
log.  0,6724334 
log.     0,6467606 


VV   log.  0,4035762 

MJU    log.  0,6724334 
MM                                         ^ 

— —  =  1,8571935  log.  0,2688572 

L  =  1,8942294 

Approximate  x  =:  0,0370359 

Corresponding  |  =  0,0000801     in  Table  IX. 
L  —  4  =  1,0608961 

L  —  ^  —  f  =    1,0608160  log.  o,02564oi 

MM    log.  0,6724334 

Corrected     H  log.  0,6467933 

Hence  we  get  from  (56),  corrected  V    =  i,59i5ii 


MM 

=  1,8370008 

YY  ^ 

L  =  1,8942294 

Corrected   x  =  0,0372196 


yy    log.    o,4o36i92 
MM    log.    0,6724334 

log.    0,2688142 


Corresponding    |  =  0,0000809    in  Table  IX. 
L  —  |-  ^  1 ,0608961 

L  —  |.  —  ^  =  1,06081 52              log.  0,0256397 

MM    log.  0,6734334 

Corrected    H                                  log.  0,6467937 

Hence  we  get  from  (56),  corrected  V    =  1,5915124 

VV    log.  o,4o362oo 

MM    log.  0,6724334 

MM  „,      ,,  .         

. =  1,8570064                log.  0,2688134 

L  =  1,8942294 


X  =  sin2.Jg  =  0,03722  3o 


To  find  MM.      (5o) 

constant  log.  5,5680729 

?  =  2o6''''y',  80919                   log.  2,3i55698 

same  2,3i55698 

arith.  co.  log.  ( —  cos./)  x  3  1,2792738 


f  log.  r  / 


X  =  sin2.  j  g 

is 

g 
MM 


arith.  comp.     9,1939471 
MM    log.    0,6724334 

To  find  a.      (59) 


11^07'»  2C«,3 

22''  l4"»  525,6 


VV 


—  COS./ 

a 


To  find  p,  and  e  =  sin.  j.       (61,  64) 


k 
t 
rr' 

2/ 
-V 


[/a 

f,  =  75<'23wo7",3 


To  find  F,  G,  »,  »',  u,  u'.       (65,  66) 


g 

cos.  g.  cosec.  f  =  o,g565oi8 


/ 


y-r 


cosec.  0,0142840 

cos.  9,9664018 

log.  9,9806858 

cosec.  0,0142840 

ar.  CO.   log.  8,7442935 

cos.  9,5735754» 

log.  0,2686843» 


u^G —  g^= —  17''  22™  40* 
u'=G-|-g=      27'' 07™  oG" 


843 

[5995] 


(170) 


(177) 


log.  8,5708114 

sin.  9,2854057 

cosec.  0,4218017 

same  0,4218017 

log.  0,2688134 

log.  o,3oio3oo 

log.  9,5735754 

log.  0,2686843 

log.  1,2557065    (l"8) 


ar.  CO.  log.  1,7644186 

ar.  CO.  log.  7,6844302 

log.  0,5373686 

sin.  9,84i77i3» 

log.  0,2018100» 

log.  0,0297987 

log.  0,6278532 

COS.  9,4019455    (179) 


(180) 


-  '^'"'■'coa./.  cosec 
a 

?  =  0.0398875 

log. 

8,6008372 

COS. 

G  =  0,9963893 

log. 

9,9984291 

(181) 

G 

f 

g 

4''52mi3» 

sin. 

sin. 

cosec. 

sin. 

8,9289080 
9,9671659 
0,4218017 

(162) 

F  = 

9.3178756 

a83) 

/= 
v  =  F—f=- 
v'  =  F-\-f= 

112'' 

-  lOOl* 

124<i 

G 

g 

=       4'' 52'»  1 3* 
=      22''  14"  53» 

(184) 

844 

[5995] 


APPENDIX,  BY  THE  TRANSLATOR; 


EXAMPLE    II. 


(185)  Given    log.  r  =  0,3307640,    log.  )•'=  0,3222239,    »'— «  =  2/=  7''34™  53',73,    t  =  ^i^^^^gSSgi  ;    to  find 
the  elements  of  the  orbit     a,  p,  e  =  sin.?  ;     the  true  anomalies     v,  v'  ;     and  the    excentric   anomalies     u,  u'. 

(186)  A  considerable  part  of  the  calculation  of  this  example,  is  given   in  the   introduction  to   tables  VIII,  IX  ;  and 
it  is  unneecessary  to  repeat  it  here  ;  we  shall  merely  give  some  of  the  results  of  this  part  of  the  process  ;  namely, 


(187) 


i  =  o,ooii2o5685  ;    log. — -  =  7,27i5i33;    log.™  =  o,oo2i633  ; 


w  =  —  bm  275  ; 

log.mS  =  7,2736766  ;        log.y/rr'  =  0,3264940  ;        x  =  sin2. ig  =  0,0007480186. 

With  these  we  shall  compute     a    by  the  formula  (58)  ;    p     from  (60)  ;     «f     or     f     from  (64)  ;     G     from  (65)  : 
F    from  ((56)  ;  then    v,  v',  u,  u',    from  (i3— 16). 


(188> 


(189) 

(190) 
(191) 

(192) 
(193) 


To  find    a. 

^g        I"*  34»'  02S,o3 

g-     y  o8">  o4^",o6 

2 
/ 

a 


log.  6,8739124 

sin.  8,4369562 

cosec.  1,2621764 

same  1,2621764 

log.  7,27i5i33 


log. 

COS. 


o,3oio3oo 

9,9990488 

log.        0,3264940 

log.        0,4224389 


To  find   p,    and    e  =  sin.  ?. 


k 

ar.co.log. 

1,7644186 

t 

ar.co.log. 

8,658884o 

rri 

log. 

0,6529879 

=sf 

sm. 

9,1203696 

y 

log. 

log. 

0,0010816 

Vv 

0,1977417 

Va 

log. 

0,2112194 

<»  = 

l4'i  12m  02^,0      COS. 

9,9865223 

cos.gf.cosec.  ? 


To  find    V ,  !)',«,  u^ 


COS.     9,9993498 
cosec.     0,6102727 

4,0702635  log.     0,6096225 


Vr. 


\/r 


a 
f 


cosec. 

ar.co.log. 

cos. 

log. 


0,6102727 
9,5775611 
9,9990488 
o,3264g4on 


.co3./.cosec.f=— 3,261 1940  log.     0,5133766», 

cos.G?  =       0,8090695  log.     9,9079858 


log.e  =  log.sin.j    9,8897273 


G  —  324<'oo"'  i8«,4  sin. 
/=.  3<'47™26»,865  sin. 
g  cosec. 

F  =  3 14'' 42"  54',95  sin. 
/  =      3"*  47™  26^86 

V  =F  —f  =  310''  55m  28' 
d'  =  ^"4-/=  3i8<'3o"'22' 

G  =  324''  00"'  i8«,4 
g-  =      3''  o8mo4«,i 

u  =  G  —  g  =  320''  52»  i4« 
«'  =  G  4-  g  =  327''  08»  23'. 


9,769  i653„ 

8,8202909 

1,2621764 

9,85i(5326„ 


In  this  example,  cos.  G  is  positive  (189)  ;  but  sin.  G  (25)  is  negative,  because  r'  —  r  is  negative  ;  therefore 
G  must  fall  in  the  fourth  quadrant  [5990,  (23,  24)].  Again,  sin.  F  (190)  is  negative,  and  cos.  F,  deduced  from 
(22),  is  positive  ;  therefore  F  falls  in  the  fourth  quadrant. 

These  examples  will  suffice  for  illustrating  the  calculations  in  an  elliptic  orbit  ;  we  shall  now  proceed  to 
explain  the  similar  calculations  in  a  parabolic  orbit. 


PARABOLIC   ORBIT,  COMPUTED  FROM     r,  r',  «'  —  «  =  2/. 

TO  FIND  THE  ELEMENTS  OF  A  PARABOLIC  ORBIT,  THERE  BEING  GIVEN    r,r',    u— r=2/. 

In  a  parabolic  orbit,  we  shall  use  the  symbols  (2 — 10),  most  of  them  being  similar  to  those 
in  an  ellipsis  [5995(6,  &ic.)]-  We  shall  also  insert  in  the  same  table  (11 — 25),  several 
formulas  which  are  useful  in  these  calculations  ;  and  shall  afterwards  give  the  demonstration 
in  (26—60). 

r,  r,     the  radii  vectores  ; 

V,  v  ,     the  mean  anomalies  ; 

p=2D,     the  semi-parameter  ;     [5986(2)]. 

D  =  ^p,     the  perihelion  distance  ; 

2f  =  v'~v;  v  =  F—f; 

2F=y'+v;  v'=F-\-f; 

r'  =  r.tang-.sr  ; 

cos.y  =  cos.yisin.2z  ; 

Cfc  =  1  —  f.sins.iy  ;  log.fe  =  8,2355814 . . .  [5987(8)]  ; 

^  =  co3.(|F—  i/)  =  cos.iy  ; 


|-,  =  cos.(iF+i/)  =  cos.iy'; 


845 

[5996] 


(1) 


(2) 

Symbols. 

(3) 

(4) 

(5) 

(6) 

•(7) 

(8) 
(9) 
(10) 


Fonnulas 
in  a  para- 
bolic orbit. 

(12) 


\/r? 

J-(r+r') 
2rr' 


=  cos.i^-{-  cos.f; 


1  +  cos.J'.cos./; 


(13) 


(14) 


p  = 


2rr'.  sin^./ 


r  -f  r' —  2.cos.f.^/r7 


sm.z.sm.f\2 
.    sin.|y     J 


(15) 


2.sm.f.cos. f.rr'  ,   4.sm^. f.(rr')^      l/2     ,     .    .  „    ,    , 


V/p 


r 


2.C03./ 


3p^ 


=  1+2/; 


=  CA; .  <  -^^—  >    .  sin.iw. 
(  cos.z  )  "^ 


fcf 


m 


2^.{cos.ff.{rr'Y 


log.m2  =  5,5680729  -|-  2.1og.<  -  3.1og.cos./—  |.log.(rr')  ; 
VOL.  III.  212 


[Assumed  "I 
value  of  Z.J 

[Assumed  l 
value  of  m- J 


(16) 


(16) 


(17J 


(18) 


(19) 


846  APPENDIX,  BY  THE  TRANSLATOR  ; 


[5996] 

(20) 

sin2./^,T'  _ 
^^     2/.C0S./  ' 

(21) 

,«=Z2_J_^p. 

\/?  +  v^^_,  , 

2.C0S./ 

M-                ^' 

(23) 

^"3                   s          a  ' 
2^.  (-cos./f.(rr')* 

[Assumed    1 
value  of   L.J 

[Assumed    "I 
value  of    Jl/.J 


sin^./l/r/ 

(24)  p= — ~Y^ — -; 

— 2L.C0S.J 

(25)  M  =  —L^^%Û. 

The  formulas  in  the  prececiing  table  are  easily  demonstrated  in  the  following  manner. 

(26)  Substituting     D=lp    (5),  in  the  first  expression  of  »•    [5986(4)],  we  get     '>'==- — — -  ; 
whence, 

\^£  =  cos4v  =  cos.{hF-if)     (6); 

and  in  like  manner, 

^|,  =  cos.|«'  =  cos.aF+i/-)     (7); 

these  agree  with  (11,12).  Multiplying  the  product  of  the  two  formulas  (11,12),  by  2,  and 
then  reducing  the  second  member,  by  means  of  [20]  Int.,  we  get  (13).  Taking  the  sum  of 
the  squares  of  the  two  expressions  (11,12),  and  reducing,  by  means  of  [6,27]  Int.,  we  get, 
as  in  (14)  ; 

^:^^±^Ucos^(iF^/j+cos^.(|F+è/)=l+|.cos.(F-/)+|.cos.(i^4/)=l+cos. 

Multiplying  (13)  by  — cos/,  and  adding  the  product  to  (14),  we  eliminate  cos.F, 
and  obtain, 


(26') 


(27) 


(28) 


]).  (?•  +  r')  —  2p. COS. f.\/rr' 

2^y 


(29) —^r:j ■ —    =  1  —  cosV=sin-./; 


which  is  easily  reduced  to  the  first  form  (15).  If  we  substitute,  in  this,  the  value  of  /  (8), 
we  get  the  first  of  the  following  formulas,  and  by  successive  reductions,  using  y  (9),  we 
finally  reduce  it  to  the  second  of  the  forms  (15)  ; 


PARABOLIC  ORBIT,  COMPUTED  FROM     r,  r',  v'  —v  =  2/.  847 


(29') 


(30) 


(31) 


2.tanf.z.sm^.f  ^.sin^.z.sm^.f  2.sm^.z.sm^.f 

p  ^  )• .  — :^  r. '■ =  r. 

l+tang-.z — S.cos./.tang.z         1 — 2.cos./.sin.«.co3.2         1 — cosyisin.S^ 

â.sin^.z.sin-./"        2.sin-.s.sin-.f  /sin. «.sin. 

=  r. ^  =  r.— — r— ^  =r.[  ' 

1  —  cos.ij  2.sm'~.iy  \    sm.ly 

Substituting     D=lp     (5)    in  [5986(6)],  we  get, 

p  ^ 
i!  =— .  {tang.|y  +  ^.tang». 'j;]  ; 

and  by  accenting  the  letters, 

f  =g.{tang.|«'  +  e.tang3.|t;'*.  ^3,,, 

Subtracting  the  first  of  these  expressions  from  the  second,  and  changing  t'  —  t  into  t, 
in  conformity  with  the  notation  of  this  article,  we  shall  get,  by  multiplying  by  k,  the 
expression  (32).     The  second  member  is  easily  reduced  into  two  factors,  as  in  (33  or  34)» 

3 

kt  =  If.  j  (tang.iu'  —  tang.iu)  -f-  i.(tang3.i«'  —  tang^i?>) }  Oa, 

3^ 

=  \'p'^ .  \  tang.iu'  —  tang.iu  M 1  +  i-tang^.|u'  +  itang.iw'.  tang.|«  +  |.tang^.|y  \  (33) 

3 

=  Ijj^.^tang.iy'  —  tang.U'^.p  +tang.!w'.  tang.iu  +  iV.(tang.|u'  —  tang.|«)^}. 
Now  we  have, 

sin.iy'       siniy        sin.|«'.cos.iv — cos.lu'.sin.iu      sin.(àî)' — \v) 

tang.|«'  —  tang.Ju  =  — —, ~  =  - — ^— ^^  =  — ^ ^-^ 

cos.il!       cos.|u  cos.^D  .cos.iu  cos.|j;.cos.|w 

sin./ 


[599(5] 


(34) 


COS.iîj'.COS.jU 


and  the  product  of  the  expressions   (11,12),  gives    £5-^^;=  =  cos.|u'.  cos.jU  ;     hence  the     (ss) 
preceding  expression  becomes, 

,  ,                         2.sin./.i/P7 
tang.iu'  —  tang.iv  = .  ^3^, 

By  similar  substitutions,  we  obtain, 

.    ,  ,         •  cos.iîj'.  cos.iî)  4- sin.|u'.sin.i«       cos.(W — Iv)  cos.f 

I  +  tang.iy'.  tang.iu  = = ~ —=: ^^^ ~=^ ^ 

cos.èD.cos.|y  cos.jW  •  cos.jW       cos.iy  .cos.jj;  O') 


2.C0S./  \/rr' 


P 
Substituting  (36,37)  in  (34),  we  get, 


{37') 


848  APPENDIX,  BY  THE  TRANSLATOR 

[5996] 


1  (  2.C0S.f.[/rr' 

(38)  Kt  =  p^.  Sin./  ^rr'  ■  <  '- 1  i 

3 

2.sin./.cos./.rr'       4.sin^/()T')^ 


2.sin./.v/;7\2 


(39) 

This  last  expression  is  the  same  as  the  first  of  the  formulas    (16).     If  we  multiply  the  last 

term  of  the  second  member  of  (39),  by    p,     and  divide  it  by  the  first  value  of    jj      (15)- 
we  get, 

2.sin./'.cos./!rr'      2.sm.f.^^.ir-\-i-' — S.cos./.^/iy  }       2.sm  f.\/rp.\ r-\-j'-\- cos. f.\/^'\ 

Substituting  in  this  last  expression,  the  first  value  of  i/p  (15),  we  get  the  second  expression 
(16).  These  two  forms  of  Gauss,  are  reduced  to  the  form  (16'),  by  Burckhardt,  in  the 
*^''  following  manner.  Substituting  the  assumed  value  /  ^  r.tang^.z  (8),  in  the  second 
expression  (16),  we  get  (42)  ;  and  by  successive  reductions,  using  the  symbols  z,  y,  C 
(8,9,10),  we  finally  obtain  the  expression  (43),  which  is  the  same  as  (16'), 

i/2    ^ 
(42)    kt  =  ^—--  r^.{l  -\-  tang^.2: -j- cos.f.tang.z] ■  f  1  +  tang^.5:  —  2.cos./.tang.z}^ 
o 

l/2     ^ 
=  - —  r^sec.'z.{l  +cos./.sin.2;.cos.2;].|  1  —  2,cos./.sin.z.cos.z]* 

i/2    ' 
=  î— -.  r^.  sec.^z.U  +  J.cos./.sin.2x|.|l  — cos./.sin.25:|* 

=^.  A  sec.^z4l+l.cos.yl.\l—cos.yf=^.Asec.^z.\l+i.(l-2.smUy)]4^-sirr'.lyl'^ 


_V/2 


1  3 

^.r^.sec.^z.{| — sin^.ly} . 2 ^.sin.Jy  ==?•'.  sec.^^.Jl  —  f.sin^.|y}.sin.|2/ 


(43) 


=  r^  sec.^r.CA:.sin.|y=Cfc.  f  ^— )  .sin.ij/. 


To  facihtate  the  use  of  this  last  formula,  Burckhardt  computed  Table  VII  of  this  collection, 

which    contains  the  values  of  the  logarithms  of     C  = ^- — '— ,     for   intervals   often 

minutes  in  the  value  of    y,     from     y  =  0''     to     y  =20'';     and  by  means  of  it,  we  can 
(**) 

very  easily  compute  the  time    t,   corresponding  to  the  radii     r,  i\     and  the  included  arc 

2/"=  v'  —  V  ;     as  may  be  seen  in  (J3),  or  in  the  example  which  is  given  on  the  same  page 

with  the   table.     The  assumed  values  of    l,m,  L,  M    (17,18,22, 23),  are  precisely  the 

('5)    same  as  in  the  ellipsis  [5995(28,37,48,50)].     Multiplying  (17)  by     2.cos.f.\/T?,     we  get, 

r'  -{-  r  =  2.C0S. f.\/r7  +  Al. cos. f .\/^ , 


PARABOLIC  ORBIT,  COMPUTED  FROM 


?-,  V- 


v=2f. 


hence  the  denominator  of  tlie  first  expression  in  (15),  becomes  4Lcos.f.i/'iy  ;  and  tlic 
value  of  p  is  reduced  to  the  form  (20).  Again,  since  (17)  is  reduced  to  llie  form  (-22), 
by  changing  I  into  — L,  we  may,  m  the  same  way, get  (:24)  from  (20).  Substituting  the 
value  of    p     (~0)}  J"  t'l^  first  expression  of    Jet     (IG),  we  get. 


849 

[599G] 

(■IB) 


kt  =  P.(2.cos/)^(^■')'  +  i-l--{2-cos.f)-.{rry  =  21  cos.y.(  rry.{l^  +  |./^- j .  m 

Substituting  this  in  the  value  of  ?»  (IS))  it  becomes  of  the  very  simple  form  (21).  In  a 
similar  manner,  the  substitution  of  the  value  of  p  (21),  in  let  (16),  and  then  in  M 
(23),  gives  (25);     and   this  maybe   derived  from  (21),  by  changing,  as  in    [5995(127)] 

/    into  —  L,    and    m    into     J\I.{ — 1)=.     If  we  compare  the  equations  (21, 25)  with  the     (43, 
similar  ones  in  an  ellipsis,  [5995(40,  53)],  we  shall  find  that  they  agree,  if  we  suppose 
x  =  0,    or    sin^.|5-  =  0;    whichmakes     |=0     [5995(115)].     Henceit  is  evident,  that  in 
calculating  an  orbit,  upon  the  supposition  that  it  is  an  ellipsis;   if  we  obtain    x  =  0,    that  is 

to   say       — — Z  =  0,  or   —  —  L=0,     [5995(47,  57)],  we  may  immediately  conclude     (49) 

that  the  orbit  is  a  parabola,  and  we  can  then  calculate  the  elements  of  the  orbit,  by  any  of 
the  formulas  in   the   preceding   table  (11 — 25).     Thus  we  may  find    jj    from   (15  or  20),     (50) 
also,     D=^\p,     and  then  we  may  obtain     F    from  (13  or  14).     We  shall  illustrate  these 
formulas  by  the  following  example. 


EXAMPLE. 
Given  in  a  parnbolic  orbit   log.  j- =  0,2476368,    log.  7^=0,2929648,  and  k'  —  ï  =  2/  =  3o''  18'"  43»,  to  find 
the  elements  D,  p  ;  the  anomalies  v,  v'  ;  and  the  time  of  describing  the  arc  t. 

To  find  t.  To  find  p,  D,  v. 

4  log.  r'    o,t464S34 
k  log.  r    o,i23Si84 


z  =r  46*  29"'  39»  ,6 

2Z  =  92''  59""  195,2 
J^  15"*  09"'  21« 

y=^  i^i  26"'  27»,2 


v/r .  sec.  2 


43/=  7^43"  i3>,6 

*  =  5â''=5'%6222 


tang.     0,0226640 


sine  9,9994089 

COS.  9.9846256 

COS.  9,9840345 

J  log.  r  o,i238i84 

COS.  9,8378575 

log.  0,2859609 

Multiplied  by  3  0,8578827 

Table  VII.  log.  C  1,7591607 

sine  9,1282047 

log.  1,7452481 


/ 
z 

iy 


r 
P 


D  =  ip 


i/J?   =cosa.4t' 

r     2r 

iv  =  3''  3o"'  53" 


sine 
sine 
ar.  CO.  sin. 


9,4173807 
9,86o52i4 
0,8717953 


sum 

doubled 
log- 
log. 

0,1496974 

0,2993948 
0,2476368 

o,547o3i6 
o,3oio3oo 

log. 
log. 

P,346ooi6 
0,2476368 

log. 

9,9983548 

COS. 

9,9991824 

ble  III. 
log. 

0,7037928 
0,3690024 

(51) 


(52) 


{ô:î/ 


Time  from  tlie  perilielion  cori-espoading  to  r,  f,  1 1       ,83  48     log.     i  ,0727052 


VOL.    III. 


213 


850 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5997]         TO  FIND  THE  ELEMENTS  OF  A  HYPERBOLIC  ORBIT  ;  THERE  BEING   GIVEN   THE  RADII     r,  r ,     THE   ANGLE 

v'  —  v=2f,    AND  THE  TIME    t    OF  DESCRIBING  THE  ANGLE    2/. 

We  shall  here  use  the  same  symbols  as   in  the  elliptical  orbit  [5995(G,  &:c.)],  changing 

C 

'■'    M     into     —,       and     u'     into     Cc;      using    also    the   auxiliary  angle     -^^     [5988(3)]. 

For  convenience    of  reference,    we    shall    insert    these   symbols    in    the    following    table 
(3 — 9,  &,c.),    together  with  the   formulas  which   are  used  in   this  method   (9 — 59),  and 


(2) 


their  demonstrations  in  (60 — 172). 


Symbols- 

(3)  r,  r'     the  radii  vectores  ; 

(1)  V,  v      the  mean  anomalies  ; 

(5j  «=     the  semi-transverse  axis     =  6. cot. 4-; 

7  1  •         •  •  //  o        1  \       s'm. f.\/r? 

(0)  0=     the  semi-coniugate  axis     =  rt.i/(e 1)  =  — ; 

^  *'  ^  V  V  /        tang.2w   ' 

(7)  p  =:  «  (e^  —  1)  =  i>-\/e^  —  i  =  «.tang.-4^  =  i.tang.-^]^  =  semi-parameter  ; 

(8)  e  = 

Formulas  COS.-i. 

fur  a   hy-  " 

perbolic 


;  secant  4-  =^    excentricity  ; 


urbit. 


.        tang./",  tang. 2?j  tang./'.tang.2n 

(0,    ^/ea_i=tang.+  =-^^''       -       -  ^./       ^       . 


2.{_l-z) 


2.{L+z) 


(10)  i«=-; 

(11)  u'  =1  C  c; 

(12)  c  =  tang.  (45"  +  »)  ? 

(13,      Z=\.    ^^^C-^jY', 

(14)  C  =  tang.(45''  +  W); 

c^ 5- — 4.1og.c 

(15)  z  = T —  ; 

(16)  tang.2?i  =  2.\/(7+l2)  ; 

2.sin.4'.tang.2w 

(!')    taiig.2JV=— ^ ; 

^  sin._/.cos.2i« 

(18,      2f=v'-v;  v^F—f; 

(19)     2F=i''-f-i;;  v'=F+J; 


[Corresponding  to  r,  v.] 
[Corresponding  to  r',  v'.  \ 


(20)     sin.gï^-    ? 


(21)    cos.^y=è 


,    ^ 


^ 


^+ 


il 


^   _  C  — c sin.(JV— «)  . 

(22)     tang.^w—  ( c+c). tang.H"  cos.(yV  -f-  ?i).tang.l+  ' 


HYPERBOLIC  ORBIT,  COMPUTED  FROM     r,r',v'—v,t!—t.  851 

[5997] 

\).a  ) 


COS 


sin 


Cc—V  _  sin.(JV  +  «) 

(Cc+ l).tans.i4.         cos.(JV — ?i).tang.^4. 


Ce 


a  c  ^  }   i.        c  ) 


/-j-j' 


,2\2 


y/'^  =  tans.(45'^  +  w)  ;  )çX'-  =  tang.(45'^-  iv)  ;  [v^of t] 

'"      1      I        /  _  [-When    cos./l  r  Assumed  T 

"1~    \/         /  L  13  positive.   J  Lvalueof  I. S 


r  V        r 


s.cos.y 

sin^.J  f  ,   tang^Sw 

^+ — ^^ 

COS./  cos.y 

2*.(cos.y)^.(/T')^ 


=  1+2?; 


(24) 


tang.ij;  =______-__    =  _      ^^/     ^^  ^_  ;^  ^  ,   ;  (25) 


(20) 


cosf^la  .  I  r.{  C  +  -  )-(  c-  4-  i)  I  .(^-^J;  (27) 

(28) 


,i„.F=J..|c-I|.|^|"; 

c».F=i«.|,(.+l)-(c+i)j.(l,)i 

r  (   C        c    } 

-  =ke.  <  — +y,  ?  —1  ;  (30) 

r'  C  1    ) 

-  =  le  .  ■?  Cc+-p;-  ^  —  1  ;  (31) 


(3S) 


(33) 


2  _  (1  +  ^z).{z  +  r^)^  - log.{v/i— .  +  y/z i  ^3^j 


2.(,-  +  c^) 


(36) 


(37) 


(38) 


r  .^S3ume.l    1  (39J 

l_vaIi)o  of   m.  J  ^     ' 


852 

[5997] 

(40)  m 

(41)  y  '■ 

(42)  h  = 

(43)  h  = 

(44) 


APPENDIX,  BY  THE  TRANSLATOR  ; 


irC' 


(y-i)y 
y+i 

o 

TO-  _ 

y 


(45) 


r 


m  L  - 

(47)  Jll  : 

(48)  31 

(49)  5^. 

(50)  H 

(51)  j;^ 

(59)  2 
(53)        T' 
(53') 


^ =  1  —  2L  ; 

2. COS./ 

sin.^i/         tang^.2ît' 

COS./  COS./ 

t« 

=  _(L+c)*+(L  +  cy*.z=  r.(L+~)'; 


=  -^  +  (^  +  ^~)-^  =  -(L+^*' 


M2 


(Y+1).Y 

1 


y— T-   ' 


=  ya""  ^  ' 


=  —  .  ?  ^ liyp.log.tang.(45''  +  ^)  \ 


a"    CXe.tang.2A' 

=  . — .  < ^ comm.  log.  tang 

Xk   (      cos.2)j 


,(45"+^)|: 


(54)       i^  =    — 


rt'     C  e.tang.2;i        ,         ,  fArd,\}. 

^         --^- hyp.  log.  tang.  (45*  +  n)  > 


COS.! 


(54') 

(54  )      loi 


[Assumed   I 
value  of   y.] 

[Assumed    ~| 
value  ol    h.j 


r  When  COS.    /"[  r    Assumed     "1 

L    is  negative,    J  Lvalue  ot    /-.J 


[Assumed    1 
value  of   JI.} 


C   Assumed      I 
value  of    rj 

[Assumed       1 
vplue  of    H.  J 


3  -^ 

-=  -_     )  ^^^^ comm.  log.  tang.  (45 '+  n)  >  ; 

Xk     I     C0S.2A  ) 

5.fe=  8,2355814  ...  :         log.x  =  9,6377843  ...  ;         log.-  =  2,1266342  ...  ; 


HYPERBOLIC  ORBIT,  COMPUTED  FROM     r,  r',  v' —  v,  t' —  t.  853 

[5997] 


■r 


' + '•  -  ('+ ]y°^-f-\^'  __  ^  •  1  ^  -  ^  W'  -  ^cj  \  •  "^"^^v/^ 


-  8  .  ^  L  +  f  (v/c  -  ^)'  I  •  cos./V^ 


2.(1  —  z) .cos.f.\/T?      2m^.  cos./.v/;y fc^_5^ 

tang^Srt  y-.  tang^.  2»  ~  4  j^.  ?•/.  cos.y.tang-.  2?j 


—  2.(.L  +  =:)  .cos/.y/^y  _  —  2.J\P.  COS./.  y/^    _ 


k^fi 


P 


tang'-.  2«  r^.  tang2.  2»i  4  Y^.  rr'.  cos.y. tang2.2n  ' 

siii.y;tang./.\/JT'       «/^.  sin./.tang./.\/Jy         /i/.rr'.sm.2f.^ 


■2.(1— z)  2m^ 


/i/.rr'.sm.2f.\^ 

=  V    ^f     ) 


—  sin/.tang./!^/jT'        —  Y^.  sin./.tang/.v/ir' /  V.rr'.  sin.2f  N^- 

2.(i  +  c)        "^'  2jiï^  ^\         kt 


(55) 


(55) 


(50 


(57) 


(58) 


<59) 


We  shall  now  give  the  explanations  and  demonstrations  of  the  formulas  in   this  table, 
taking  them  generally,  in   the  order  in  which  they  occur.     The  symbols    (a  —  9)    are    '^''') 
similar  to  those  in  the  table,  page  767,  or  like  those  for  the   ellipsis,  [5995(6 — U)],  page 
831,  changing   as   usual      I  —  e^     into     «^ — 1,    &c.  ;    the   formulas    in      (6,  9,  17),    cei) 
depending  on    /    will  be  noticed  in    (149,150).     We  have  iu     [5988(13)], 

M  :=  tang.  (45"  +  ^  w),  («i-, 

and  in  like  manner, 

u'  =  tang.  (45"  +  i  zi).  jsa. 

When  the  quantities  w,  -u^  have  been  obtained,  from  the  times  t,  l',  by  means  of 
[5988(6  or  7)],  we  can  easily  deduce  u,  u'.  Instead  of  the  symbols  w,  zs',  Gauss 
uses  the  quantities     c,    C,     putting, 

'  =  { '3m?) i  *=&'  '=  !.a«,.(«'+,.).,.„,(«-+;.0!*=(...O^;    .« 

these  values  give, 

-=tang.(45"+J^)=u    (61');  Cc  =  tang.(45"+ ^^')  =«'    (62);  (64, 

being  the  same  as  in     (10,11).     In  the  course  of  the  calculations,    the    new  symbols 
VOL.  III.  214 


854  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5997] 

n,  JV,  z,  Z,     are  introduced,  depending  on     c,  C     These  assumed  values  are  given  in 

(12— 15),  in  terms  of    c,  C.     Ifweput,  in     [5989(12,14)], 


(70) 


(71) 


(72) 


the   first  of  these  expressions  will  become  as  in    (12)  ;    and  the  last  form  of  [5989(14)] 
will  give, 

c^— 1         /  1 


(65) 


(66)  tang.2n  =  -—  =  i[c  —  - 

Novv  the  assumed  form  of    z     (13)  gives, 

(67)  y/r=i.\à—c-i  i  ;      ^r+-z=i.ià-\-c-i ]  ;      /rfi-f- v/r=ci  ; 

(68)     \/z.\/ï+-z  =  ^ï+T^=i.{c-c-^);        z=i.(c-2  +  c-');        l+2z=h{c  +  c-^)- 

Substituting  the  first  of  the  expressions  (68)  in     tang.2«     (66),  we  get  (16).     Dividing 
the  numerator  and  denominator  of  (15)  by  8,  it  becomes, 

|.(c2_c-)_log.c* 

<691  ^  :=: 


è-(c-c-)' 


Now  the  product  of  the  first  and  third  of  the  equations  (68)  gives, 

l.{c^-c-^)  =  {\4-2z).{z  +  z^f; 

moreover  the  third  power  of  the  first  of  the  equations  (68),  being  multiplied  by  2, 
produces, 

i..{c-c-^f  =  2.{z  +  z^f; 

substituting  these  and  the  value  of  â,  given  by  the  third  of  the  equation  (67),  in  (69), 
we  get  (34)  ;  which  is  reduced  to  the  form  (35)  in  (119  &;c.)  The  assumed  values  of 
/,  F  (18,  19)  are  similar  to  those  in  the  eUipsis  [5995(13,  14)].  If  we  divide  the 
last  of  the  expressions  of  sin.J?;,  cos.|j;  [5988(18, 20)],  by  i/r,  and  substitute 
the  corresponding  values  of    i«  =  -(10),      we  shall  get     (20,  21).     The   similar  values 

of    sin.|»',    cos.il)'     (23,  24)   are  found  in  the  same  manner,  by  merely  accenting  the 
(73)     letters     r',v',     and  using     u' =  C  c     (11),  instead  of  the  value  of    ii     (10).     Dividing 
(20)  by  (21),  we  get,  without  any  reduction. 


Oc-i—C-ià      /e  +  l\^ 


tOrtfT     ■*-'i1  r  I       

(74) 


Multiplying  the  numerator  and  denominator,  of  the  first  factor  of  the  second  member  of 
this  expression,  by     O  à,     it   becomes     ^^  ;    and  we  have  as  in  [5988(3)], 


HYPERBOLIC   ORBIT,  COMPUTED  FROM    r,r',v' —  v,i' —  t.  856 

,      V  [59971 

(74'; 


e  —  ly  tang.  ^  ^  ' 

hence  we  get  the  first  of  the  expressions  of    tang.^u     (22).     The  second  expression  can 
be  deduced  from  the  first,  by  substituting  the  values  of    c,  C     (12, 14).     For  if  we  put, 
for  a  moment,      45<'-|-n=n',      Ai»" -\- N  =  JV' ,     the    expressions    (12,14)     become    (75) 
c  =  tang.?i'  ;     C  =  tang.JV'  ;     hence  we  get, 


„                       ,,,                ,       sin.JV'       sin.w' 
C  q=  c  :=  tang.^-'  q:  tang.n'  = —  zp  ■ 


cos.JV'       cos.n' 

__  sin.  N'.  COS.  w'  ::p  cos. N'.  sin.?t'        sin.(JV"  zp  n') 
cos.JY'.cosm'  cos.JV'.cos.w' ' 

and  if  we  divide  this  expression  of     C —  c,     by  that  of     C  -{-  c,     we  obtain, 

C—c_sm.(JV'  —  n')  sin. (.A''—  n)        _  sin.(JV— n) 

C+c  ~sm.{JV'+n')  ""siu.(90<'-|- JV+n)  "^  cos.(JV+  n)  ' 


(76) 


(76') 


(77) 


substituting  this  in  the  first  expression   (22),  we  get  its  second  form.     In  like  manner,  by      ,g 
dividing  (23)  by  (24 J,  we  get  the  first  expression  (25)  ;  hence  w-e  may  obtain  its  second 
form,  by  substituting  the  values  of    c,  C     (12,  14).     It  is,  however,  easier  to  derive  (25) 
from  (22)  ;  observing  that  if  we  change     c     into     c~^ ,     in  (20,  21),  we  shall  obtain  the 
formulas  (23,  24)  respectively  ;  moreover  the  change  of    c    (12),  into    c~'  ,    requires  that 


(79) 


we  should  change    tang.(45''-l~  ?;)     into    r~;77w'77~;  >     or    tang. (45''  —  n)  ;     which    is 

equivalent  to  a  change  in  the  sign  of  n;  making  these  changes  in  (22),  we  obtain  (25) 
by  a  slight  reduction.  Multiplying  (21)  by  (23)  we  get  (SO)  ;  also  (20)  by  (24)  gives 
(81)  ;  (21)  by  (24),  gives  (82)  ;  and  (20)  by  (23)  gives  (S3), 

sin.lv'.cos.iv  =  ia.  \  C 7-,  +c i  .  \ ;-   ^  ';  (80) 


,i.'.cos.|«  =  ia.[c--^,+c-  -i^  .  Y^]^; 

,   ,    •  ^  ^         1  1   >       (c^—  1  )  i 

cos.Ju.sm.iy  ^  ia.  <  C  —  "ri  —  c  +  —  ,"•  .  <    ;—  }  -; 

i  ^  c    )       (_      rr       'i 

cos.4y'.cos.4«  =  ia.^  C+  -^+c  +  -|  • '^^  5. 

f  1  1^6+1 

sin.V.  sin.^«;  =  |a.  ^       "^  C"~'^"~75  '  777)i  ' 


(81) 


(82) 


(Kl) 


irr') 
Subtracting  (81)  from  (80),  and  substituting  in  the  first  member  for, 

sin.Ju'.  cos.^D  —  cos.Jt;'.  sin.i«,  (84) 

its  value,      sin.(|i;' — ^v)  =:  s'm.f    (18),  we  get  (26).     In  like  manner,  the  sum  of 


856  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5997] 

(82,83),  gives  by  substituting  for  the  first  member,  its  value      cos-dw'  —  ^v)  =cos.f, 

the  expression  (27).     The  sum  of  (80,81),  substituting     sm.F  ^=  sm.{^v' -\-iv)     (19), 

(85)  gives  (28)  ;  lastly,  by  subtracting  (83)  from  (82),  and  substituting  cos.F=^cos.{^v'-}-iv), 
we  get  (29).  Dividing  the  last  expression  of  r  [5988(12)]  by  a,  and  substituting  the 
value  of    u     (10),  we  get    (30);  accenting    r,  u,     and  substituting     u'     (11),  we  get 

W     (31).     Subtracting  (30)  from   (31),  we  get  (32);  and   the  sum  of  (30,31)  gives  (33). 

(86)  The  assumed  values  of  w,  I,  m  (36, 37, 39),  corresponding  to  the  case  of  cos./  positive, 
are  the  same  as  in  the  ellipsis  [5995(24,28,37)]  respectively  ;  and  the  resulting  value  of  / 
[5995(31)],  is  the  same  as  in  (38).  The  similarvalues  of  L,  M,  (45 — 47), corresponding 
to  the  case  of  cos./  negative,  are  also  the  same  as  in  the  ellipsis  [5995(48 — 50)].  If 
we  substitute  the  value  of  tang.«  [5939(14)],  and  tang.  (45''  -|-  Aw)  [5989(12)]  in 
[5988(6)],  it  becomes, 


(88) 


(91) 


(93) 


k 


(87)  -.t  =  ie.]u  —  -[  —  hyp.  log.w, 


iu-l\- 


a2 


r'-«5 


and  by  accenting     t,  u,     we  get, 

—  .t'  =  he  .)  u' ;  (  —  hyp.  log.w'. 

Subtracting  the  first  of  these  expressions  from  the  second,  then  changing  t'  —  t  into  t, 
to  conform  to  the  notation  in  this  article,  we  get  (90)  ;  which  is  easily  reduced  to  the  form 
(91),  by  the  substitution  of  the  values  of  u,u'  (10,11);  eliminating  e  by  means  of 
(27),  which  gives, 

C  1  1  )      ,      m' 

=  |e.|c+^|.^c-^|-2,log.c 
Jc— -^cos./.v/;y  <;         1) 


(89) 


(90)  -.1 


we  get  (92), 
h 
a' 


Eliminating     e,     from  (33)  by  means  of  (89),  we  get,  by  making  a  slight  reduction. 


(93)  :=   i    C  -\- 


a 


HYPERBOLIC  ORBIT,  COMPUTED  FROM     r,  r',  v' —  v,  f —  t.  857 

whence  we  easily  deduce  the  first  value  of    a    (55).     Multiplying  (37)  by     2.cos. /.\/r7,  [5997] 

we  get,     r'  -}-  r  ^  (2  -j-  Al). cos .f.\/rr'  ',     substituting  this   in   the   preceding  value   of    a  (94) 
(55),  we  obtain, 


(2  +  4/).cos.//r7  —(c  +  -Ycos././ï^  8 .  ^  /  —  i.  ("c  -  2  +  ^-)  I  cos.f.^ 


(95) 


which  is  easily  reduced  to  the  second  form  (55).  The  third  form  is  easily  found,  from  (45) 
by  a  similar  process  ;  or  it  may  be  easily  derived  from  the  second  form,  by  changing 
/  into  — Z,,  as  in  (37, 45).  If  we  substitute  the  value  of  z  (13),  in  the  second  and 
third  forms  of  (55),  we  get, 

9.{l—z).cos.f.{rr'f  _  —8.{L -\- z).cos.f.{rr'y- 
Multiplying  (15)  by     ^.(c j      we  get, 


substituting  this  in  the  second  member  of  (92),  and  then  multiplying  by     a^,   we  get  (100).     m) 

Now  the    square   root  of  the  first  expression  of    a     (97),  being  multiplied  by     c , 

gives, 

(c  -  ^) .  a*  =  2Ï.  (I  -  z)i.  (cos./)i  (rrf  ;  ^99, 

substituting  this  and  its  cube  in  (100),  it  becomes  as  in  (101), 

let  =  ^c  —  -  j  .  a*,  cos./,  {rr')^  +  ^-{^~\)  '  "*■  ^  (WJ 

=2l  (cos./)Mrr')^.  |  (/-  zf  -^{l-zf.  Z\  ;  <"»'^ 

hence  the  value  of    m     (39)  becomes  as  in  the  first  form  of  (40)  ;  and  by  substituting  in  it, 
the  assumed  value  of    yz=\-\-Q,  —  z).Z     (41),  it  becomes     m=-y.{l  —  «)*,     as  in  the     (io2) 
second  expressions  (40, 41).     Squaring  this  value  of    m,     and  dividing  by     if,    we  obtain    (io2) 
z     (44).     By  a  similar  process,  usmg  the   second  value  of    a     (97),  we  may  reduce  the 
value  of    M     (47)  to  the  first  form  in  (4S)  ;  and  by  substituting  the  assumed  value  of 
y=  _  1  +  (L  +  z).Z   (49),  we  get  the  second  forms  of    M,  Y    (48, 49)  ;  finally,  fi-om    ("«) 

VOL.  III.  215 


858  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5997] 

these  we  easily  deduce     z     (52).     We  may  also  obtain   (48)  from   (40),   by  the  same 

process  of  derivation  which  is  used  in  [5995(127)],  namely,  by  changing, 
(104)    I     into     —  Z,  ;  m     into     M\ — l)i;  y     into     — Y;  and     li     into     iî. 

By  developing  in  series,  we  obtain, 

(104.)  \/{z  +  z')  =z^-^  Iz^-  \zi  +  &c.  ; 

multiplying  this  by     1  +  2s,     we  get, 

(105)  (  I  +  2z)y  (s  +  z^)  ^è^  f  J  +  |s* + &c. 

Moreover, 

(106)  ^iqi7+^5:=l   +si-t-is  — ^22_j_gjc.  ; 

whose  hyp.  log.,  by  (58)  Int.  is, 

(107)  hyp.  log.|v/r+7  +  \/z\  =  (sl+  \z  -  iz^  +  &c.)  - U^-  +  ~2Z-  iz^  +  ^c.f 

+  i.(zi  +  is  —  &c.)3  —  J-.(si  +  is— Sic.)*  +  &c. 

=  {zi  +  is  -  iz--  +  &c.)  -  i.(s  +s*  +  Iz^  -  is*  +  &c.) 

_j_  a .  (J  +  |,2  +  3^*  _|_  &c.)  -  I  .(S^  +  |S^  +  &iC.)+iS^+&C. 
1,  3.  Sl 

(108)  — ■'    — s'^    -Titr^    — ^^■ 
Subtracting  (108)  from  (105),  we  get, 

(109)  (I  +  2^)-/(-  +  z^)  —  hyp.  log.  {/Î+;  +  i/s}=  I  s^+  is*  +  &c., 
moreover,  the  cube  of  (104')  is, 

(s  +  s2)*  =  #+fs*  +  &c.; 
substituting  these  expressions  in  (34),  we  get, 

(110)  z  =  ll±A^+^-  =  t  +  f^  +  &^-  _._,,,    &e. 

2.(si  +  iJ+&.c.)       l+i~'  +  ^c.  ^    ^- 

To  obtain  the  law  of  this  progression,  we  shall  multiply   the    value  of    Z     (-34),  by 
2.{z-^z^f,     which  gives, 

(HI)  2.(s+s2)i,_z^  (1  _f.  2s).(^+  s7—  log.{/r+i  +  /s|. 

The  differential  of  this  expression,  being  divided  by    dz,     gives,  without  any  reduction. 


HYPERBOLIC  ORBIT,  COMPUTED  FROM     r,  r',  v'  -v,t'-  t.  859 

[5997] 
3.{z  +  s^.  (  1  +  2^)  .  Z  +  2.(^  +  z^)k  ^  (112) 

=  2.(^  +  z^y  +  1.(1  +  2zy.  {z  +  z^)-^ ^J:-i+-_^^-  ^  .  cnao 

The  last  term  of  the  second  member  being  reduced,  by  rejecting  the  factor    ^1+2  +  \/^ 
which  occurs  in  its  numerator  and  denominator,  becomes, 


hence  that  second  member  may  be  put  under  the  following  form,  by  taking  the  terms  in 
the  same  order  as  in  (112'),  and  bringing  the  factor     ^.{z  +  s^)^  ,     without  the  braces  ; 

i.{z  +  z'^)-i.\4.(z  +  z^)  +  {l+2zr-l}=:i.{z  +  z"^)-i{S.{z-\-z^)\=A.{z  +  z"-)K     (IM) 

Substituting  this  in  (112'),  and  then  dividing  the  whole  equation  by  {z-\-z^)-,  we  get, 
by  transposing  the  term  depending  on     Z, 

(2z  +  2z^).'^  =  4  —  {3-\-6z).Z.  d'S) 

If  we  compare  this  equation  with  that  in  [5995(107)],  we  find  that  the  former  may  be 
derived  from  the  latter,  by  changing  X  into  Z,  and  x  into  —  z  ;  making  the 
same  changes  in  [5995(112)]  which  is  deduced  from  [5995(107)],  we  get, 

^       ^       4. G       ,4.6.8-       4. 6. 8.  10,       4. 6. 8.  10.  12      ^ 

^=  *-  3—5  ^  +  3TTT^^-3.5.7.9^   +    .3.5.7.9.11   "  ^  -  ^^-        ""'' 

Making  the  same  changes  in  [5995(114,116)],  and  writing  Ç  for  |,  v/e  obtain  (117,118); 
substituting  the  second  of  these  expressions,  in  the  first,  we  get  (119),  ^ 

10        5  2  52 

9Z=6+^+35-~'-i575-"'+^'^-'  '"'^ 

2  52 

^=35-^'- 1575  •^'  +  ^''-'  '"'> 

10         5 

From  the  last  equation  we  obtain  the  value  of    Z    (35),     In  Table  X,  are  given  the     (120) 
values  of    Ç     (118),  corresponding  to     z  ;     from     2  =  0,001     to     «  =  0,300;     which 
are  to  be  used  in  solving  the  equation  (40  or  48),  as  we  shall  see  hereafter,  (130 — 134). 
The  comparative  magnitudes  of    z,  ?,     in  Table  X,  have  a  striking  analogy  with  those  of        ' 


<125) 


(126) 


(127) 


860  APPENDIX,  BY  THE  TRANSLATOR  ; 

^^^^^'^     a;,  I,     in  Table  IX  ;   as  is  easily  seen  by   the  inspection   of   the  tables  ;    moreover,  in 
(122)     consequence   of    the    smallness  of    ?,      in  comparison  with      z,      we  may  in  the  firsi 
approximation    towards  the   values   of    z     neglect      Ç,      as   we   have   neglected     |     in 
''^^     [5995(146,  &;c.)].      If  we  now  assume  for     h     the  value  (42),  we  shall  get, 

,    ,   ,  m2 

(124)  5    _]_  /  4-  ^   =    _    . 

Substituting  this,  and  the  value  of    z     (44),  in  the  expression  of    Z"'      (35),  we  get  by 
successive  reductions, 

Z-  =  i  +  «.(^  +  O  =  ft.(t  +  ^  +  0  =  ft-(n-'  +  ?-5)  =  -ft{?-5) 

=ft-e^')-"i=.v(^')-('-)^ 

whence  we  obtain, 

(^— )-^  =  -'^-(,'^,); 

and  by  substitution  in  the  assumed  value  of    y     (102  or  41),  we  get, 

(128)  y_i^io,(jL_^       or       (?/  — i).(f-A)  =  -^^.A; 

whence  we  easily  deduce  the  value  of    h     (43).     In  like  manner  we  may  obtain,  from 
the  assumed  values  of     Y,  H,     (49,  50),  the  expression  (51).     This  may  also  be  very 

(129)  easily  deduced  from  (43).  by  the  principle  of  derivation  (104)  ;  observing  that  if  we 
chan<^e  the  signs  of  the  numerator  and  denominator  of  (42),  and  then  make  the  changes, 
which  are  indicated  in  (104),  it  becomes  as  in  (50). 

We  may  deduce  the  value  of    z,     from  the   cubic   equation   (43  or   51),  in  the  same 

(130)  manner  as     x     is  obtained  from  [5995(46  or  56)],  in  [5995(145,  &tc.)]  ;  by  first  neglecting 

(131)  I,      on  account  of  its   smallness,   and   putting,     ^''  =  j-j-j  (42),  or  H=£— — ^  (50). 

With   this  value  of    h     or     H,     we  find  in   Table  VIII,   the    corresponding   value  of 

(132)  \q„  y  y  or  log.  Y  Y;  and  then  from  (44  or  52),  the  approximate  value  of  z  ;  also  from 
Table  X,  the  con-esponding  value  of  Ç.  Tliis  opération  is  to  be  repeated  till  the  assumed 
and  computed  values  of   Ç    agree,  and  in  general,  it  will  be  found  that  one  single  operation 

'     is  sufficient  to  give  a  very  close  approximation  to   the  true  value.     Hence  we  see  that  the 
calculation  for  finding     z,     in  a  hyperbolic  orbit,  is  nearly  the  same  as  that  for  finding    x 

(134)  in  the  ellipsis  ;  and  we  may  observe  that  the  cwaji^fes  -^  —  ^  ^~'W  [^995(47,57)], 
which  are  positive  in  the  ellipsis  [5995(47,57,41)],  becotne  negative  in  the  hyperbola, 
(44,  52, 13),  and  vanish  in  the  parabola  [5996(49)]  ;  so  that  the  sign  of  these  functions, 
determines  the  nature  of  the  conic  section. 


(135) 


(135) 


HYPERBOLIC  ORBIT,  COMPUTED  FROM     ,-,  r',  v'—v,t'—t.  861 

[59971 
Having  this  computed  the  value  of  z,   tve  may  noio  consi<hr  it  as  one  of  the  data  of  the 

problem,  to  be  used  iufnding  the  éléments  of  the  orbit.     The  value  of     c     may  be  found 

from  the  formula, 

f- I +2- +  2.^(2 +=2);  (130 

which  is  easily  deduced  from  the  first  and  third  of  the  equations  (6S)  ;  by  multiplying  the 
fu-st  of  these  equations  by  2,  and  adding  the  product  to  the  third  equation.  Wemay  also 
obtain     c,     from  the  formulas  (16, 12),  namely, 

tang.Sn  =  2.[/{z  -\- z~)  ;  c=  tang.(45''  +  n).  (is?) 

The  remarks  in  [5995(131 — 144)],  relative  to  the  roots  of  the  cubic  equation  in  y  or  Y, 
corresponding  to  the  ellipsis,  may  be  applied  also,  with  proper  modifications,  to  the  hyperbola, 
as  is  evident  by  considering  that  the  formulas,  [5995(46,56)],  in  the  ellipsis,  are  of  the  same 
forms  as  those  in  the  hyperbola  (43, 51).  Finally,  we  may  observe,  that  if  z  exceed 
the  limits  of  Table  X,  we  may  use  the  indirect  methods  of  solution,  without  changing  the 
form  of  the  equation  (40  or  4S).  In  this  last  case,  if  we  suppose  the  elements  of  the  orbit 
to  be  known  approximatively,  we  may  determine  very  nearly,  the  value  of  n,  by  means 
of  the  formula. 


tan2;.2ji  = 


sin/V»" 


cos.  2ft 

which  is  easily  deduced  from  (16)  ;  for  if  we  square  (16),  and  add  1  to  both   members   of 
the  resulting  equation,  we  get, 

1  +  tang-.  2n  =  l-\-4z  -{-  Az^    or     sec^.  2«  =  (  1  +  2^)2  ; 

whence     sec.2rt  =  1  -|-  2z,     and, 

sec.2?i — 1 1 — cos.2ft       'i.sm^.n         sin^.w 

2  2.cos.2«         2.cos.2«         cos.2«  ' 

This  value  of    z,     is  to  be  used  in  finding     K    '"  Tabic  X;  and  then  a  corrected  value  of 
h     or     H    (42, 50),  may  be  obtained,  which  must  be  substituted  in  (43  or  51),  to  obtain 

VOL.  III.  216 


(138) 


(139) 


which  is  easily  deduced  from  (26),  by  the  substitution  of, 

i.u  —  -  )  =  tang.2?j    {my  <"'> 

Then     z    may  be  deduced  from     n,    by  the  following  expression  of  its  value, 


(142) 


(143) 


862  APPENDIX,  BY  THE  TRANSLATOR; 


[5997] 

(144) 


a  more  accurate  value  of  y  or  Y.  These  operations  arc  to  be  repeated  till  we  obtain  a 
value  of  y  or  Y,  which  will  satisfy  the  equation  (43  or  51)  ;  and  then  from  (44  or  52), 
'"^'  we  get  the  true  value  of  z,  to  be  used  in  Computing  the  elements  of  the  orbit.  We  shall 
now  give  the  demonstrations  of  the  remaining  formulas  in  the  preceding  table,  which  are 
used  in  this  part  of  the  computation. 

Comparing  the  first  of  the  equations  (68)  with  (16),  we  get 

1 


(146) 


(151) 


(154) 


4Y(s  +  s^)  =  2.tang.2«  : 


and  we  have,  in  (13), 


substituting  these  in  the  second  and  third  of  the  formulas  (55, 55'),  we  get  the  first  of  the 

(147)  formulas  (56,57)  respectively.     Substituting  in  these,  the  value     I  —  z  =  —      (44),  and 

(148)  L-\-z^y^     (52),  we  get  the  second  expressions  in  (56,57).     Substituting  the  value  of 

m^,     (39),  in  the  second  form  of  (56),  we  get  its  third  form  ;  and  in  like  manner,  by  using 
JVP     (47),  we  may  reduce  the   second    form  of  (57)    to  its   third   form.     The  value  of 

(149)  «v/e2 — I,     deduced  from  (140),  is  the  same  as  the  last  of  the  formulas  (6).     Dividing  this 

(150)  by  the  first  of  the  expressions  of  a  (.56),  we  get  the  second  form  of  \/e^—\  -(9);  and 
in  like  manner,  by  using  the  first  value  of  a  (57),  we  get  the  third,  or  last  of  the  formulas 
(9).     Multiplying  the  equations  (26,32)  together  crosswise,  and  dividing  the  product  by 

^•{c j,     which  occurs  in  both  members,  we  get, 


.(c-i).si„/=  (,.'-. ).(^v-y- 


(152)  If  we  change,  in  (12),     c    into     C,     and     n     into     N,     it  becomes  as  in  (14),  and  by 
making  the  same  changes  in  (66),  which  is  derived  from  (12),  we  get, 

(153)  tang.2iV  =  ^.(C  —  —\ 
We  have  also,  as  in  [5995(30)], 


/  —  r  /r  /r  4. tans; 

{n-y  ~vV~  V      r'  ~     C0S.2 


2îw 
'iw'' 


Substituting  these  and 

(155)  e  =:  sec.4'  ;         (e^  —  1)^  =  tang.-l     (8,9), 

in  (151),  it  becomes, 

4.  tang. 214) 
(155)  2.sec.+.tang.  2iV.sin./  =  -^^^^  ■  tang.+  ; 


HYPERBOLIC  ORBIT,  COMPUTED  FROM    r,  r'  v'  —  v,  t' —  t.  863 

[5997] 
dividing  this  by     2.sec.4..sin./,     we  obtain  the  expression  of    tang.2A'     (17).     The  third 

expressions  of   p     (53,59),  are  the  same  as  those  in  the  ellipsis  [5995(60,61)]  ;  they  can     (i56) 

be  easily  deduced  from  (6),  by  squaring  it,  and  then  dividing  by     a,     by  which  means  we 

get,  for     «.(e- — 1),     or    p     (7) ,  the  following  expression  ; 

SYn?f.rr' 

P  = ^-  ;  ''*'> 

«.tang^.2n 

substituting  in  this,  the  last  of  the  values  of  «  (56,57),  and  using  2.sin./.cos./=  sin.2/, 
we  get  the  last  of  the  values  of  p  (53,59).  From  these  we  easily  obtain  the  second 
forms  (53,59),  by  putting     sin.2/ =  S.sin.yicos/,     and  using,  in  (53),  (i58) 

{]ctf  =  S.{cos.f )^(rrY.m^     (39);  (i58) 

and  in  (59), 

{]dy'  =  8.{—cos.fy.{rr')^.J\P     (47).  dss",' 

,.2  1 

Lastly,  substituting  in  the  second  form  (58),  the  value     ~  z= (44),  we  get  its  first     (iso) 

form;  in  like  manner,  by  using     —  = -— ;      (52),  we  reduce  the  second  form  of  (59)     ;,60) 

to  its  first  form.  Instead  of  representing  the  times  from  the  perihelion  of  the  first  and  second 
observations  by  t,i',  as  in  (87,83),  we  shall  now  represent  them  by  T — ^t,  and 
T-^-^t,     and  then  the  two  expressions  (87,38)  will  become, 


aoi) 


:^.  (T  -  10  =  è  c/u -^-)-hyp.  log.M  ;     -^.{T+it}=ie/u'-  V\-hypAog.u'. 

3 

The    half  sum  and  the  half  difference  of  these  two  expressions,  being  multiplied  by    ff 

k 

give  (163,165),  and  by  the  substitution  of  the  values  of   u,u'    (10,  11),  we  get  their 
second  forms  (164, 16G)  ; 

0 

«^    <        /  ^         C         1         c  \  ) 

Now  if  we  use  the  values, 


(162) 


(103) 


(1G4) 


(165) 


(I6f.) 


864  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5997] 

(167)  c=  tang.  (45"  +  n)  =  tang,  n' ;         C=  tang.  (45''  +  JV)  =  tang.  N', 

(12,  14,  75),  we  shall  have  as  in  (66,  153), 

(168)  c =2.tang.2n;         C — ^=  2.tang.2JV; 

and  by  using    [30"]    Int.  we  get, 

2  c  2.tang.?i'  .     „   , 

(169)  — .^  g  =  -^2_^=sin.2n  =cos.  27i  ; 

1  -\-  c^       l-[-tang."'n 

(169')  ,    ,    „„  =  ,    i'  r^'  2  A/-'  =  sin . 2  JV'  =  COS.  2  JV  ; 

1  _|_  C^       I  -j-  tang. ''.A' 

substituting  these  in  the  first  members  of  (170,  171),  and  making  successive  reductions,  we 
finally  obtain, 

^      ,    C        I-        c       l+c2    /^        1\  2        ^  ^^,       4.tang.2JV 

(170)  Cc-i 7^ -^=-J—.{C—  ^)= r-.2.tang.2JV=  ^ : 

'     '  '    c       C  c       C  c        V  C/      COS.  2»  °  cos.2?i 

Cl,cl  +  C2/1\  2„  „         4.tang.  2n 

(171)  Cc— -^4--—= — '-^ — .(c 1= ^;-^».2.tang.2n= ^r^^-   . 

''"'  c       Cc  ^    C  C       \        c]      C0S.2JV  °  C0S.2JV 

Substituting  the  last  expressions  (170,  171),  and  also  c,  C  (167)  in  (164,166),  we  get  the 

(172)  first  values  of  T,\t  (53,  54),  adapted  to  the  use  of  hyperbolic  logarithms  ;  the  second 
forms  (53',  54'),  are  adapted  to  common  logarithms,  by  using  the  factors  X,  Xit,  (54"). 
which  are  the  same  as  in  [5988(8,  9)]. 

To  illustrate  the  preceding  formulas,  we  shall  give  the  following  example,  from  Gauss. 


EXAMPLE 


(173) 


Given     log.  »-  =  o,o333585,     log.  j-'  =  o,2oo854i,     «'  — «=  2/=48<i  12",      (  =  5 1 '■^^■',49788.     To  find  the 
elements  of  the  orbit    a,  p,  e,    and  the  true  anomalies    v,  v'. 

We  have  given  the   calculation  of    z,    in  the   introduction  to  Table  X,  and  it  is  not  necessary  to  repeat  it 

(174)  here.      The   results  of  this  calculation  are      10  =  2"*  45"' 28',47      /  =  OjoSygôoSSS  ;       log. -5  =  8,7030725, 

(175)  log.  ^i/ ^  O,o56o846,     log.  m2  =  8,7591571      log.  y'^rs  0,1171063,      z  =  o,00748583.     With    these   we  shall 
compute    n    from    (16),    4    ^''o^    (9)»    t>    from  the  last  of  the  formulas  (6).     From  this  we  shall  deduce 

,j75>     a    and    p,    by  means  of  (5,7)  ;    ^    is  deduced  from    (17),    «,  »'     from  the  last  of  the  formulas   (22,  26)  ; 
lastly,    T,  t     from  the  formulas  (53',  54')-  The  computation  of   t,   is  made  merely  for  the  purpose  of  verification, 
(l"7)     as  it  is  one  of  the  data  of  the  problem. 


HYPERBOLIC  ORBIT,  COMPUTED  FROM  r,  r',  v'  —  v,  t'  —  t. 

To  find    n.    (i6). 


z  =  0,00748583 
I  +  Ï  =  1 ,00748583 

V^  (: +•  22)  =  è-tang-  2« 

2 

3n  =  9*5i"'ii",8i6 
»i  =  4<'55"'35»,9o8 


log.  7,8742399 

log.  0,0032389 

log.  7.8774788 

log.  8,9387394 

log.  o,3oio3oo 

tang.  9,2397694 


To  find    4.  (9). 

i=  0,057960388 
z  =  0,00748583 

Z_s  =  o,o5o474558   log.co.  1,2969275 

/  =  24<'6'"        tang.  9,6506199 

è log-  9.6989700 

tang.  2n  (as  above)  9,2397694 

4  =  37<'34"59«,77        tang.  9,8862868 

To  find    V.     (22). 

n=  4*55'"35',9o8 
JV=  8''o/i"'53«,i27 

JV — n=  3*09'"  I7',2i9  sin.  8,7406274 

jV-j-ji=  t3''oo"' 29',o35     ar.co.cos.  0,0112902 

4  4  =  18'' 47"»  29^,885  cot.  0,4681829 

4»=  9'' 25"  29s  ,97  tiing.  9,22oioo5 

i)=i8''5o'"59',94 

To  find     T.     (53'). 

{x  ft)-!  constant  log.  2,1266342 

a     (in  column  2)  log.  0,6020619 

ai  log.  o,3oio3o9 

Factor  log.  3,0297270 

\e     (in  column  2)  log.  9,7388027 

2rt  sec.  0,0064539 

2J\''     (in  column  2)     tang.  9,4621341 


First  term  of  r=  I72''''^^63o56  log.  i.,iZ-!w;i 

Factor     (above)  log.  3,0297270 

45<H-A' log.tang.         0,1241703  log.  9,0940177 

Second  term  of  r=—i32''"y^96725  log.  2,1237447 

r=      39''='y^6633I 
è<=      25<'^y^7489I 


a  =  6.  cot.  4    (5) 
p=6.tang.4 


To  find    b,  a,  p.  (6,  5,  7)- 

/  sin.  9,6110118 
y;^.  log.  0,1171063 
arith.  co.  0,7602306 


6  log.     0,4883487 

4    (in  the  first  column)     tang.    9,8862868 


log.    0,6020619 
log.    0,3746355 


To  find    jY.    (17)- 
/  arith.  co.  sin.    0,3889882 

2  log.    o,3oio3oo 


4 

2tO 


5<!  3o«  56',94 
2j\r      i6<'  09'"  46',253 


sin.    9,7852685 

sec.  2oi56 

tang.     8,9848318 


tang.    g,462i34i 


To  find    V'.    (25). 

ar.  CO.  COS.  0,0006587 

sin.  9,3523527 
same  0,4681829 

Jb' =  33"^  3iin  295,93                   tang.  9,8211943 

v'  =  67''  02"'  59»,86 

To  find    it,    (54');  Jor  verificatioti. 

\                       constant  log.  9,6377843 

e  =  sec.  4                                      '°g-  0,1010184 

A  e                                      log.  9,7388027 
3,0297270 


2«    (as  in  column  i)      tang.    9,2397694 

2j\r 


First  term  of   ^t  =  Io6''''J^I2393 

4i^-\-n]og.t3ng.  o,075o575 
Second  term  of  Ji  =  8o*''5'^375o2 


sec. 

I75I42 

log. 

2,0258i33 

log. 
log. 

3,0297270 
8,8753941 

log. 

i,9o5i2ii 

it=   25'^'^J■^7489I 
it  =   25''''J'S 74894  by  observation. 
o''*J'^,oooo3  difference. 


ît —      i3       .91440  =  time  from  the  perihelion  of  the  first  observation. 
r+4<=      65  ''^^4I222  =  time  from  the  perihelion  of  the  second  observation 


866 

[5997] 


(178) 


(179) 


(180) 


(181) 


(182) 


(183) 


VOL,    III. 


217 


866  APPENDIX  BY  THE  TRANSLATOR  ; 

[5998] 

'-  ■'  GAUSS'S   METHOD  OF  CORRECTING  FOR  THE  EFFECT  OF  THE  PARALLAX  AND  ABERRATION  OF  ANY  NEWLY 

DISCOVERED    PLANET    OR    COMET,    IN    COMPUTING    ITS    ORBIT,    BY    MEANS    OF    THREE    GEOCENTRIC 
OBSERVATIONS,  WITH  THE  INTERVALS  OF  TIME  BETWEEN  THEM. 

In  the  computation  of  the  orbit  of  a  newly  discovered  planet,  by  the  method  in  [5999],  it 

(1)  becomes  important  to  avoid  the   trouble   of  repeating,  with   much  labor,  the  preliminary 

(2)  calculations,  similar  to   those  in  [5999(300 — 379)],  to  correct  for  the  effect  of  the  planet's 
parallax,  which  at  the   commencement  of  the   calculation   is  wholly  unknown.     This  is 

(•''>     effected  in  a  very  elegant   manner  by  Gauss,  by  applying  an  equivalent  correction  to  the 

(4)  place  of  the  earth  in  the  ecliptic  ;  supposing  at  each  observation,  a  fictions  or  second  observer 

(5)  to  make  the  observation  of  the  planet.      The  place  of  this  second  observer  being  in  theplcme 
of  the  ecliptic,  at  the  point  where  the  line  drawn  from  the  planet,  through  the  actual  place  of 

(^'  observation  on  the  surface  of  the  earth,  and  continued  beyond,  intersects  the  plane  of  the 
0)  ecliptic.  It  being  evident  that  the  geocentric  latitude  and  longitude  of  the  planet  is  the 
same  in  both  places  of  observation  ;  but  the  distances  of  the  planet  from  the  two  observers 
will  be  varied,  by  the  distance  of  tiie  two  places  of  observation.  In  consequence  of  this 
change  of  place,  we  must  apply  a  small  correction  to  the  distance  of  the  earth's  centre  from 
the  sun  ;  and  also  to  the  longitude  and  latitude  of  the  earth,  so  as  to  reduce  them  to  the 
assumed  situation  of  the  second  observer.  After  these  reductions  have  been  made,  the  rest 
'^'  of  the  calculation  must  be  continued  ;  supposing  that  the  second  observer  is  situated  at  the 
times  of  the  three  observations,  in  the  three  points  of  the  ecliptic,  deduced  in  the 
abovementioned  manner,  from  the  actual  places  of  observation  ;  since  it  is  a  matter  of 
indifference,  from  what  places  the  planet  is  observed,  provided  we  carefully  ascertain  the 
assumed  positions  of  the  places  of  observation,  which  are  used  in  the  calculations. 


(8) 


(10) 

(11) 


We  shall  put,  at  the  time  of  any  observation, 

(12)      A  =  ISO'  +  ©  =  the  heliocentric  longitude  of  the  earth's  centre  ; 
,13)     L  =  the  heliocentric  latitude  of  the  earth's  centre  ; 
R  =  the  distance  of  the  centres  of  the  earth  and  sun. 

(15)  In  like  manner  ./3„  L^,  R^,  represent  the  heliocentric  longitude,  latitude,  and  distance  from 
the  sun's  centre,  of  the  place  of  the  first,  or  actual  observer,  upon  the  surface  of  the  earth. 

(16)  Also,  Jl„,  L„,  R^,  the  corresponding  heliocentric  longitude,  latitude  and  distance  of  the  second 
or  fictions  observer. 

(17)  a,  Ù,     the  geocentric  longitude  and  latitude  respectively  of  the  planet  ;  being  the  same  for 
both  observers  ; 

(18)  pi  the  distance  of  the  planet  from  the  first  observer  ;     p,  +  P„     its  distance  from  the  second 
observer  ;     p^     the  distance  of  the  first  and  second  observers  from  each  other. 

Z   the  longitude,  and  z  the  latitude  referred  to  the  ecliptic,  of  the  first,  or  actual  observer, 

(19)  O  '  i 

as  seen  from  the  centre  of  the  earth  ;     r,  the  distance  of  the  first  observer  from  the  centre 
of  the  earth. 


TO  CORRECT  FOR  THE  PARALLAX  AND  ABERRATION. 


/ 

First  Observer  yy 


We  shall   suppose  that  the  plane  of 
the  annexed  figure  90,  is  the  plane  of 
the  ecliptic  ;     S,  the  place  of  the  sun  ; 
(St,  the  line  drawn  from  the  sun  towards 
the  first  point  of  aries  ;      C,  the  centre 
of  the  earth  ;     O',  the   actual  place  of 
the  first  observer  ;  F,  the  corresponding 
place  of  the  fictious  or  second  observer  ; 
CC,    010',  perpendiculars  let  fail, 
upon  the  ecliptic,  from  the  points  C,  O', 
respectively  ;       C  A,     F  B,      O  E, 
perpendiculars  let  fall  upon  Sf;     also,  ■Son 
FH,  C  G,  perpendiculars  let  fall  upon 
OE;    lastly,  C  I  is  drawn  parallel  to  CO.     Then  by  the  preceding  notation  we  have, 

SC'  =  R;  SO'=^R^;  SF  =  R,;  C'0'=-t; 

°{'SC=A;  rSO=^jlr,  'Y'SF=A_; 

OCG  =  Z;      0'C'I=z;  OFH^o-;  0'FO  =  ê; 

and  by  the  usual  rules  of  plane  trigonometry  we  have, 

SC=,SC'.cos.L  =  iî.cos.Z,;     CC  =  IO=R.sm.L; 

SA  =  SC.cos.CSA  =  SC.cos.A  =  R.cos.L.cos.A  ; 

CA=GE=R.cos.L.sm.A;     C'I=  CO  =  C  O.sm.O'C I=t.cos.z  ; 

TO'  =  C'0'.sin.O'CI=T.s\n.z  ;     CG=AE=CO.cos.OCG=  CO.cos.Z=t.cos.z.cos.Z. 

OG  =  r.cos.s.sin.Z ;     SB  =  SF.cos.FSB  =  R„.cos.A„  ;     FB  =  EH=^ R^.s\n.A^  ; 

FO  =  FO'.cos.O'FO  =  FO'. cosJ  =  p,.cos./)  ;     00'  =  FO'.sm.aFO  =  p,.sm.ô. 

FH  =  BE=  F0.C05.  OFH=  FO.cos.o.  ^  p,.cos.0.cos.a  ; 

OH=FO.sm.OFII  =  p^.cosJ.sin.a. 

Now,  by  referring  to  the  figure,  we  evidently  have, 

SB  +  BE=SA  +  AE;        EH  +  0H=  GE-{- OG;        00' =10 +  10'. 

Substituting  the  values  (27 — 31')  in  (3:2),  we  obtain  the  three  following  equations, 

R„.cos.A„  -\-  pj.cosi.cos.a  =  iî.cos.Zy.cos.,^  +  r.cos.z.cos.^; 
R^.sm.A„  -\-  pj.cos.ô.sin.a  :=  iJ.cos.L.sin..^  +  r.cos.z.sin.^  ; 
p,.sin.é  =  iî.sinX  -j-  r.sin.z. 


867 

[5998J 

(20) 
(31) 


(22) 

(23) 

(S4) 


(25) 
(25) 
(26) 

(27) 
(270 
(27") 

(28) 
(29) 

(30) 
(31) 
(31) 

(32) 

(33) 

(34) 
(35) 


868  APPENDIX,  BY  THE  TRANSLATOR; 


[5998] 


(41) 
(43) 

(43) 


If  we  assume   the  value  of    m     (37),  we  shall  get  from  (35),     ?„.sin.â  =  m.tang.â  ; 

(36)  whence  we  easily  deduce     p„     (40)  ;  substituting  this  in  the  second  terms  of  the  equations 
(33,34),  we  obtain  (38,39)  ; 

(37)  m  =  (R.s'm.L  +  r.sin.r).cotang.â  ; 

(38)  R„.cos.A„  =  i?.cos.L.cos.-4  +  r.cos-z.cos.Z  —  m.cos.a  ; 

(39)  R„.sm.A„  =  R.cos.L.sm.A  +  r.cos.s.sin.Z  —  m.sin.o-  ; 

(40)  i>„=m.sec.ê. 

The  equations  (37 — '40)  are  perfectly  accurate,  and  they  give  the  values  of  R„,  A„,  p„. 
Tills  value  of  p,,  is  used  in  (116, 1 17),  in  finding  a  corresponding  correction  of  the  time  t, 
depending  on  the  aberration.  Multiplying  the  equation  (38)  by  cos. ^2,  and  (39)  by 
sin..^2  ;  then  taking  the  sums  of  the  products,  and  reducing  by  means  of  [24]  Int.,  we  get 
(44).  In  like  manner,  if  we  multiply  (33)  by  — sin../3,  and  (39)  by  cos..'2,  we  find 
that  the  sum  of  the  products,  reduced  by  [22]  Int.,  becomes  as  in  (45). 

(44)  R^=:  R.cos.L.cos.{^„  —  A)  -\-  r.cos.z.cos.{Z  —  A^)  —  m.cos.(a —  A„); 

(45)  R„.s\n.(A^  —  A)  ::=r.cos.z.sin.(Z —  A)  — m.sin.(a  — A). 

On  account  of  the  smallness  of    L     and     A^  —  .1,     we  may  put, 

(46)  cos.L=l,     cos.  (^2 — A)  =  l,     s\n.{A.,  — A)  =  A„  —  A; 

also  in  (45),  we  may  change  R„  into  R  ;  hence  we  finally  obtain  from  (37,44,45,40), 
the  expressions  (47 — 50)  ; 

(47)  m  =  {RL  -j-  r.sin.2).cotang.é  ; 

(48)  R^  =  R  +r.cos.r.cos.(Z  —  A)  —  m.cos.(a  —  A)  ; 
r.cos.z.sin.  (Z —  A)  —  m.sin.  (a  —  A) 


(49) 

(50) 

(51) 


(52) 

(53) 

(54) 


Pj  =  m.sec.f). 


If  r,  m,  are  given  in  seconds,  we  must  divide  them  by  206265*,  or  multiply  them  by 
sin.P,  nearly.  With  these  formulas,  (47 — 50),  we  may  compute  the  corrections  of  the 
place  of  the  earth,  for  each  of  the  three  observations. 

In  making  these  calculations  we  must  compute  the  longitude  and  latitude  of  the  zenith  ; 
or  as  it  is  very  commonly  called,  the  longitude  and  the  complement  of  the  altitude  of  the 
nonagesimal  degree  of  the  ecliptic,  for  each  of  the  three  observations.  The  data  in  each 
of  the  observations  being  the  obliquity  of  the  ecliptic,  the  latitude  of  the  place  of  observation 
reduced  to  the  centre  of  the  earth,  on  account  of  its  elliptical  figure,  and  the  right  ascension 
(55)  of  the  meridian.  Various  methods  have  been  given  for  this  purpose  in  books  of  astronomy 
(5g,  and  navigation  ;  but  that  which  is  derived  from  Napier's  formulas  [1345  "'^'^^J, is  as  simple 
and  short  as  any  ;  it  was  published  by  me  several  years  since,  in  a  work  on  navigation,  in 


TO  CORRECT  FOR  THE  PARALLAX  AND  ABERRATION. 


nearly  the  following  form.  In  tlie  annexed  figure,  W°f  S 
is  the  equator,  E  its  pole,  P  the  pole  of  the  ecliptic,  Z 
the  zenith  of  the  observer.  Then  we  have  given,  the 
side  PE  equal  to  the  obliquity  of  the  ecliptic,  the  side 
EZ  equal  to  the  complement  of  the  reduced  latitude  of 


wm 


the  place  of  the  observer,  and  the   angle  PEZ  equal  to    -^^ 

tlie  difference  between  the  right  ascension  of  the  meridian 

and  270'',  or  the  right  ascension  of  the  arch  EP  W  ;  so  that  we  have  the  sides  P  E,  EZ, 

and  the  included  angle  P£^,  to  find  the  angle  £  P  .Z,  and  the  side  PZ.     Having  computed 

this  angle  and  side,  we  shall  then  have,  by  noticing  the  signs. 


longitude  of  the  zenith  =  90" 
We  shall  now  put,  for  brevity, 
<iS=EZ+PE; 
angle  PZE=Z; 


EPZ;         latitude  of  the  zenith  =  QO"*  —  PZ. 


A  = 


cos.D 
COS. S  ' 


2D=  EZ—PE; 

angle  EPZ=  P  ; 

angle  PEZ  = 

=  E, 

B        ■'■"«•";          C  = 

—  tang.S. 

Then  from  Napier's  formulas  [1345 ^'^S'^"],  we  have,  by  changing  the  letters  JÎ,  B,  C,  into 
P,  Z,  E  ;  and  the  arcs  a,  b,  c,  into  EZ,  PE,  PZ,  respectively  ; 

cos.x? 
tang4(P  +  Z)  =  — ^ .  cotang.JE  =  -4.cotang.JJE  ; 

COS.  O 

tang.KP—  ■2)  =  -^-^  •  cotang4i:=  B.^.cotang.|E=£.tang.i(P  +  Z); 
sm.o 

^„^       cos. I- (P+Z)  „        ^,   cos.i(P+Z) 

tang.JPZ=  V,r,       J\-  tang.S  =  C.         ■=  ^      '       ' 


cos.i(P- 


cos.  i(P—Z) 


The  values  of    D,  S,     do  not   vary  sensibly,  during  the   interval    between   the   extreme 
observations,  and  we  may  put  the  preceding  expressions  under  the  following  logarithmic  forms  ; 

2.S'  =  Polar  Distance  of  the  observer  -|-  Obliquity  of  the  Ecliptic; 

■2D  =  Polar  Distance  of  the  observer  —  Obliquity  of  the  Ecliptic  ; 

log. .4  =  log.cos.D  —  log.cos..S'  ;     log.B  =  log.tang.D — log. tang.S  ;     log.  C  =  log  tang.S. 

log.  tang.J(P+Z)  =  log.^  +  log.cot.J£  ; 

log.tang.i(P  -  Z)  =  log .5  +  log.tang.KP  +  Z)  ; 

log.tang.^PZ=log.C  +  log.cos.i(P  +  Z)  —  log.cos.è(P— Z). 

This  method  is  peculiarly  well  adapted  to  this  calculation,  because  it  is  short,  simple,  and 
VOL.  III.  218 


869 

[5998] 


{.■i7) 


08) 


(59) 

(60) 

(CI) 

(61') 

(tii2) 


(W) 

«4) 

((i51 

iUI.) 

(67; 
(67) 
(t*) 
(119) 
('«) 

on 


870 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5998] 


requires  only  four  openings  of  the  table  of  logarithms  for  each  observation  ;  moreover  the 
numbers  A,  B,  C,  do  not  sensibly  vary  in  the  time  included  between  the  extreme  observations, 
so  that  the  same  numbers  are  used  in  all  three  of  the  observations.  Thus  in  the  example 
[5999(277 — 279)],  the  obliquity  of  the  ecliptic  varies  only  0'',42,  in  the  interval  between 
the  extreme  observations.  To  illustrate  these  formulas,  we  shall  apply  them  to  the  three 
observations  in  the  example  [5999(277 — 285)]  ;  and  as  the  altitudes  and  longitudes  of  the 
zenith  are  not  required  to  any  great  degree  of  accuracy,  we  shall  only  use  five  places  of 
decimals  in  the  logarithms.  Then  the  co-latitude  of  the  place  of  observation,  [5999(281)], 
gives,  rZ  =  3S''31"'2r;  the  obliquity  of  the  ecliptic,  PE  =  23" 2T"  59' ,  [5999(277)]. 

''•*>    Their  half  sum,  and  half  difference  gives     S=  30''59"'40'  ;     D^l''3l'"4V.      Then  we 

m    have,  from  (68), 


(72) 


(73) 


(74) 


(75) 


(78) 
(70) 
(80) 


-D=  7''3i»"4i'         COS.     9,99624 
.S=:  30'' 59"  40'         COS.     9,93309 

A        log.     o,o63i5 


D        tang.     9,12107 

S        tang.     9,77868:=  log.  C 

B  log.     9,34239 


Subtracting  270''  from  the  observed  right  ascensions  of  Juno  [5999(274 — 276)],  which  was 
observed  on  the  meridian  [5999(282)],  we  get  the  resulting  values  of  E  (84),  corresponding 
to  the  three  observations  of  the  following  table.  Then  by  means  of  the  formulas  (69 — 71), 
we  obtain  the  values  of  the  angle  P ,  and  the  side  PZ.  Subtracting  the  angle  P,  from 
90*  we  get  the  longitude  of  the  zenith  (88)  5  and  subtracting  the  side  PZ  from  90'', 
(83)    vve  get  the  latitude  of  the  zenith  (89).     The  calculations  for  all  three  of  these  observations 


(81) 


(82) 


are  as  in  the  following  table. 


First  obsenation. 
(84)     R.  A.Merid, — 270^=  £  =  87'' lo"' 22".     (274). 
.S.log.  o,o63i5 
èE=43''35'"i ij  cot.  o,o2i44 


(85)  .i(P+Z)=5o''32"'42^  tan.  0,08459 
B.       .  .     log.  9,34239 


(30)  4(P_Z)=i4'*57'»53»  tan.  9,42698 

(87)       Sum  =65''3o'»35»=£PZ 
(68)     Comp.=24''29"'25*=long.  zen. 

(.89) 


Second  observation. 
JE  =  85"  43»  46».     (275). 
jî.log.  o,o63i5 
4JS:=42"'5i"'53'  cot.  o,o324o 


cos.  9,8o3io 

a  log.  9,77868 

sec.  0,01498 


è(P-fZ)=5i''i5"'09»  tan.  0,09555 
B.         .  .    log.  9,34239 


^PZ  tan.  9,59676 


èPZ=2i''33"'4i' 

/'Z=43''07"'22« 

Latitude  =  46''52'"38' 


è(P— Z)=i5''i9»46nan.  9,43794 


COS.  9,79650 
C  log.  9,77868 

sec.  0,01 573 


liPZ  tan.  9,59091 


Sum=66<'34»'55»=£PZ 
Comp.=23<'25"'o5>=  long.  zen. ^pz^ 2i<'i-jm56. 

PZ=42<'35"'52« 


Latitude  =  47''24'"o 


Third  observation. 
£=85''ii''' 10^    (276). 
A.  log.  o,o63i5 
4£=42''35"'35^  cot.  o,o3653 


è(P+Z)=5i"3i'"o6«  tan.  0,0 

B.         .  .     log.  9,34239 


.i(P-Z)=i5<f28'"o8«  tan.  9,44207 


Sum=66<'59"'i4'=£PZ 
Comp.^23''6o"'46'^long.  zen 


cos.  9,7939 
C.  log.  9,7786 

sec.  0,0160 


èPZ  tan.  9,5886 


.\PZ=  2i''n"'5'; 
PZ=  42"23"'5/ 
Latitude  =  47'i36'"oe 


These  results  are  the  same  as  in  [5999(283 — 285)]. 


(90)  ^^  ^^^^  ^^^^  '°  0^)>  ^^^  ^^™^  latitude  of  Greenwich  as  that  given  by  Gauss,  51''28"'39'; 
but  it  would  be  rather  more  accurate  to  reduce  it,  on  account  of  the  oblateness  of  the  earth; 

(91)  the  difference  is,  however,  of  no  importance,  in  the  present  example,  on  account  of  the 
smallness  of  the  parallax.     In  calculating  the  parallaxes  in  longitude  and  latitude,  in  a  total 

(92)  or  annulai-  eclipse  of  the  sun,  the  longitude  and  latitude  of  the  zenith  may  be  required  at  the 
times  of  the  four  contacts  of  the  limbs  of  the  sun  and  moon  ;  and  during  this  interval  the 
value  of    A,  B,  C,  remain  unchanged.     In  fact,  the  numbers  vary  but  very  little  in  several 

(93)  years,  so  that  we  may  compute  a  table  for  the  obliquity  23''  27™  40%  like  that  in  (96),  with 


TO  CORRECT  FOR  THE  PARALLAX  AND  ABERRATION. 


871 


die  variations  corresponding  to  a  change  of  100*  in  the  obliquity,  or  in  the  latitude,  and  by 
this  means  we  can  obtain,  by  inspection,  for  any  places  inserted  in  the  table,  the  values  of 
log.  A,  B,  C  ;  and  can  make  any  allowance  for  a  small  variation  in  the  latitude  of  the 
place  of  observation,  arising  from  any  correction  in  the  observations,  or  in  the  reduction 
for  the  ellipticity. 


[5998] 

(94) 
(95) 


Table  computed  for  the 

obliquity     23'' 

27"' 

4o«. 

Reduced 

Var. 

OS..Î 

Var.l..-../i 

Var.  log.  CI 

Places. 

latitudes. 

log.  Jl 

+ 

100» 

I0-.    B 

-)-  100' 

log.   C 

+  iuo«    1 

Lat. 

Obi. 

Lat. 

Obl. 

Lat. 

Obl. 

+ 

d     m    1 

— 

+ 

— 

+ 

Albany, 

42,27,13 

0,079670 

63 

97 

9,475733 

293 

739 

9,853328 

223 

223 

Berlin, 

52,20,24 

0,061608 

49 

75 

9,3241 35 

618 

1099 

9'77'i97 

240 

240 

Cambridge,  (E.) 

•52,01,28 

0,062166 

49 

76 

9,33  ro54 

600 

1080 

9,773925 

24o 

240 

Cambridge,  (A.) 

42,12,03 

0,0801 5o 

52 

97 

9,478383 

288 

733 

9,855355 

222 

222 

Dublin,  (Obs.) 

53,12,07 

0,060090 

48 

a 

9,3o4i66 

670 

ii55 

9,763705 

242 

242 

Edinburgh, 

55,46,0-;. 

o,o556i8 

47 

67 

9,a334oi 

878 

1376 

9,74ioii 

249 

249 

Greenwich,    (Obs.) 

51,17,28 

0,063466 

49 

77 

9,346396 

562 

1038 

9,780232 

238 

238 

Havanna, 

23,03,34 

0,120000 

64 

1 48 

9,597658 

96 

5i6 

io,oo3o45 

210 

210 

Leon,  I.  (Obs.) 

36,i6,52 

0,091680 

55 

112 

9,529940 

202 

634 

9.902005 

2l6 

216 

London, 

51,19,29 

o,c634o6 

49 

77 

9,345714 

564 

io4o 

9^779944 

2  38 

238 

Oxford,  (Obs.) 

51,34,28 

0,062963 

5o 

77 

9,34o586 

576 

io54 

9,777800 

239 

239 

Paris, 

48,38,5i 

0,068207 

5o 

83 

9,394413 

452 

9i8 

9,802627 

233 

233 

Philadelphia, 

3q,45,44 

0.084828 

53 

io4 

9,501872 

248 

687 

9,874738 

219 

319 

(9C) 


We  may  observe  that  the  same  rules  of  Napier  (63 — 65)  may  be  used  in  finding  the 
apparent  longitude  and  latitude  of  a  planet  from  its  right  ascension  and  declination,  as  in  the 
observations  which  are  computed  in  [5999(277 — 285)]  ;  supposing  in  the  preceding 
figure  91,  page  869,  that  the  point  .Z  represents  the  place  of  the  planet;  and  using  its  right 
ascension,  instead  of  the  right  ascension  of  the  meridian  ;  and  its  distance  PZ  from  the  north 
pole  of  the  equator,  instead  of  the  co-latitude  of  the  place  of  observation.  To  illustrate  this 
by  an  example,  we  shall  take  the  first  observation  of  Juno  [5999(274,277)],  namely,  right 
ascension  357'^  10™  22',35  ;  declination  6"  40'"  08'  south;  obliquity  of  the  echptic 
23''27'"  59%4S.     Hence  we  have, 


(97) 


(98) 


(99; 


(100; 


angle  FEZ  =  357"  10™  22  ',35  —  270''  =  87''  10"'  22^,35  =  E, 


Pi;  =  23''27™59',48, 
S  =  J  {EZ+  PE)  =  60''  04"'  03%74  ; 


(loi; 

EZ=  96''40'"08^  (102) 

D  =  i{EZ  —  PE)=  36''  ae™  04^26.        (102  ) 


D  sin.  9,7754222 

S     arith.  co.  sin.  0,0621735 

è£=43<^5'"i  i»,i8  cotan.  0,0214379 


.i(P—Z)=35''5i -"375,34    tan.  9,8590336 
è(P4.Z)=59''23"'28«,44 

Sumï^^gb-fi  5"'o5',78=.Ei'Z 
90 


COS.  9,9046102 

arith.  co.  cos.  0,3019201 

cotang.  0,0214379 


i(P-f-Z)=59'^23"'28M4  Ian.  0,2279683 


4(P — Z)  (io3)  ar.co.cos.  0,0912754 

iiP+Z)  (io3)  COS.  9,7068655 

S     (  1 02')  tan.  0,2397466 

iPZ=47''29'"45«,79  tan.  0,0378875     (103) 


PZ=94''59'"3i',58 
90 


Latitude     4''59"'3i'',58  south. 


354''44'"54»,22=longitude  of  Juno. 


(104) 
(105) 

(106) 


872  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5998] 

These  results  agree  with  those  in  [5999(283)].     After  we  have  found  the  angle  EPZ,  we 

may  compute  PZ,  by  means  of  the  formula  [1345'='],  which  gives, 

sm.PEZ.sm.EZ 


(107)  sin.  PZ  = 


sm.EPZ 


but  ic  is  rather   more   accurate   to  determine    P  Z  by  means   of  the  tangents,  as  in  tlie 
formula  (65). 

The  effect  of  the    aberration  of  the  planet  cannot  be  so  completely  determined  as  that  of 

(103)    the  parallax  in  the  preliminary  part  of  the  calculation  of  the  orbit.     Gauss  adopts  the  usual 

()09)   method  of  correcting  the  observed  places  for  the  effect  of  that  part  of  the  aberration  which 

is  common  to  the  fixed  stars  ;  namely,  by  adding  20',  25  to  the  longitude  of  the  sun,  which  is 

given  hy  ike  solar  tables,  neglecting  the  small  correction  from  the  inequality  of  the  motion  of 

'         the  earth,  and   applying    to  the  observed  places  of  the  planet,  the  same  corrections  for  the 

aberrationin  longitude  and  latitude,  as  if  it  were  a  fixed  star.     These  corrected  values  are  to 

be  used  throughout  the  whole  calculation  of  the  orbit.     Moreover,  when  the  distance  of  the 

(ji-i)    comet  from    the  earth   has   been  nearly  determined,   by  the  first  approximation,  as  in  the 

example   [5999('i26)],  we  must  apply  a  correction  for  the  remaining  part  of  the  aberration 

(113)  of  the  planet  ;  by  decreasing  the  time  of  observation,  by  the  time  t^,  which  is  required  by 
the  light,  in  passing  from   the   planet  to  the   earth,  supposing  it  to  take   493  seconds,  or 

(114)  0''^'%  005706,  1.1  passing  from  the  sun  to  the  earth,  when  at  its  mean  distance.  It  being 
evident  that  this  corrected  time  corresponds  to  the  actual  place  of  the  planet,  in  its  orbit,  at 
the  time  that  the  particle  of  light  quits  the  planet,  which  after  the  interval  of  time  t, , 
strikes  the  eye  of  the  observer.  Moreover,  we  may  remark,  that  these  reduced  times 
corresponding  to  the  orbit  of  the  planet,  are  those  which  enter  into  the  calculation  of  the 
orbit  in  [5999],  and  not  the  actual  times  at  the  place  of  the  observer.  Finally,  the 
correction  3<"  the  distance  i>.  =  m.sec.ê  (40),  requires  a  corresponding  correction  in  the 
aberration,  which  upon  the  same  principles  is  represented  by, 


(115) 


(116) 


d")  493^p„=  493'.m.sec.ô  =  0'"^y',005706.m.sec.ô  ;         log.0,005706  =  7,75633  ; 

but  this  correction  is  generally  insensible,  as  in  (121),  and  may  be  neglected. 


EXAMPLE. 

Given  the  geocentric  longitude  of  the  planet  «,  =  354ii  44"'  54'  ;  its  geocentric  latitude  6  =  —  4''  Sg"  32* 
(io6);  longitude  of  the  zenith  Z=  24'' 29™  (88)  ;  latitude  of  the  zenith  z  =  46'' 53"  (89)  ;  heliocentric 
longitude  of  the  earth  .d  =i2'i  aS"  54'  [5999(277)]  ;  heliocentric  latitude  of  the  earth  X  =  -f-  o'!49  [5999(277)]  ; 
distance  of  the  earth  from  the  sun  R  =  0,9988839  [5999(277)]  ;  distance  of  the  observer  from  the  centre  of 
the  earth  r^8',6o,  being  put  equal  to  the  sun's  mean  horizontal  parallax,  the  mean  distance  of  the  earth 
from  the  sun  being  supposed     206265*. 


(118) 
(119) 


(  120)        From  the  above  data  we  get     Z—  A  =  iï'^  oo'"  ;     a,  —  Az=  342''  16"" ; 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


To  find  the  correction,  of  the  time  for  the  aberration. 
m        (col.  i),  log.     i,889i3„ 

i'  sin.     4,68557 

493'  log.     2,69285 

H  sec.    o,ooi65 


To  find 

m. 

M 

log- 

9.9995" 

L 

log. 

9,69020 

«£  =  0,48945 

9,68971 

r 

log. 

o,g345o 

z 

sm. 

log. 

9,8633o 

r  sin.  z  =  6,27769 

0,79780 

Sum  =  6,76714 

log. 

o,83o4o 

e 

cot.ing. 

i,o5873„ 

m 

To  find 

R.. 

log- 

1,8891 3„ 

r 

log. 

0,93450 

z 

COS. 

9,83473 

Z  —  A 

COS. 

9,99040 

I» 

sin. 

4,68557 

-f-  0,0000279 

log 

5,44520 

—  m    . 

log. 

1,88913 

a— JÎ  . 

COS. 

9,97886 

I«   . 

sin. 

4,68557 

■\-  0,0003577 

log. 

6,55356 

Sum  =  o,ooo3856 

=  correction. 

Add  R  =  0,9988839 

gives, 

-«2  =  0,9992695 

Correction  of  lime    =  —  o«,  1 86 


log.    9,26920» 


As  this  correction  of  the  lime      — o',i86     is  so  very 
small  it  may  be  neglected. 


To  find    jîj . 

same  o,g345o 

same  9,83473 

Z—A  sin.  9,31788 

Ri  ar.  CO.  log.  o,ooo32 

+  ''.2'  log.  0,08743 

log.  1,88913 

a —  -9         ■      ■  sin.  9,4837i„ 

-^2  .      ■  ar.  CO.  log.  o,ooo32 

—  23',6i  log.  1,37316,, 

Sum  =  — 22',39  =  ./«j— JÎ;     hence, 

.«2=.;?  — 22',39 


873 

[5998] 

(121) 
(122; 


(123) 


(124) 


(125) 
(126) 


GAUSS'S  METHOD  OF  DETERMINING  THE  ORiSlT  OF  A  PLANET  OR  COMET,  MOVING  IN  ANY  fONlC  SECTION 
BY  MEANS  OF  THREE  OBSERVED  GEOCENTRIC  LONGITUDES  AND  LATITUDES,  TOGETHER  WITH  THE 
TIMES  OF  OBSERVATION. 

We  shall  here  give  the  excellent  method,  published  by  Gauss,  in  his  Theoria  Motus 
Corporum  Cœlestium,  by  which  he  determined  the  orbits  of  the  newly  discovered  planets 
Ceres,  Juno,  Pallas,  and  Vesta;  by  means  of  three  geocentric  observations,  with  the  times 
of  observations  ;  the  intervals  between  the  observations  being  small,  corresponding  to  an 
arc  of  a  few  degrees  in  the  motion  of  the  body.  The  importance  of  this  method  was 
exemplified  several  times  in  the  computations  of  the  orbits  of  these  four  planets, 
particularly  Ceres,  which  was  discovered  by  Piazzi,  a  kw  days  before  its  conjunction 
with  the  sun.  It  remained  obscured  in  the  sun's  rays  above  ten  months  ;  and 
after  the  conjunction,  was  sought  for,  in  vain,  during  several  weeks,  by  many 
European  astronomers.  It  was  feared  by  some  that  they  would  be  unable  to  find  it 
again,  and  that  it  might  be  considered  as  wholly  lost.  But  when  Gauss  furnished  the 
elements  of  its  motion,  they  were  able  easily  to  distinguish  this  very  small  planet  from  the 
numerous  little  stars  which  appear  so  much  like  it  ;    and  on  this  account,  he  may  be 


[5999] 


(1) 


VOL.    III. 


219 


874 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5999] 


(!■) 


(!■') 


(2) 


(2/) 


First 


(3) 

m 


Second 

excepted 

case. 

(5) 


considered  as  its  second  discoverer.  The  great  simplicity  of  this  method,  as  well  as  the 
rapidity  with  which  Gauss  performs  such  laborious  calculations,  was  shown  in  the  very 
remarkable  instance,  of  his  computing  to  a  considerable  degree  of  accuracy,  in  the  period  of 
about  ten  hours,  the  orbit  of  the  planet  Vesta,  by  observations  embracing  a  period  of 
nineteen  days,  with  a  geocentric  motion  of  the  planet  of  only  four  degrees. 


figure 
portion 

surface 


"/-ftV 


riaccs    ef    the    earth 


The  annexed 
92,  represents  a 
of  the  concave 
of  the  starry  heavens,  the 
sun  S,  being  the  centre 
of  this  surface  ;  ^AA'A"G 
the  ecliptic;  a  CC'C'G' 
the  heliocentric  orbit  of  the 
planet  or  comet,  whose 
elements  are  to  be  com- 
puted. ^,  A',  A",  the 
heliocentric  places  of  the 
earth,  at  the  times  of  the 
three  observations  ;  C,  C, 
C  ",      the     corresponding 


heliocentric  places  of  the  planet  ;  B,  B',  B",  the  geocentric  places  ;  the  arcs  AB,  A'B',  A"B", 
being  always  less  than  180'^.  Then  as  the  sun,  earth,  and  planet  are  situated  in  a  plane, 
which  is  projected  in  the  heavens,  in  a  great  circle,  it  is  evident  that  the  arcs  A  CB,  A'  CB', 
A"  C"  B",  are  portions  of  great  circles,  and  we  shall  suppose  them  to  be  continued,  till  they 
intersect  each  other,  in  the  points  E,  E',  E".  Lastly,  we  shall  suppose  the  points  B",  B, 
to  be  connected,  by  a  great  circle,  which  intersects  A'B'  in  the  point  B*,  and  the  orbit 
£l  G',  in  the  point  M.  From  this  construction,  it  is  manifest,  that  the  situation  of  the  point 
B*,  will  be  indeterminate,  if  the  arcs  BB",  A'B"  coincide  ;  or,  in  other  words,  if  the  points 
A',  B,  B',B",  fall  in  the  same  great  circle.  This  case  we  shall  exclude  from  our  calculations, 
cep'ted  with  the  remark,  that  we  must  select  such  observations  as  vary  considerably  from  this 
situation  ;  so  that  the  slight  errors  of  the  observations  may  not  materially  effect  the  position 
of  the  point  B*,  which  is  an  object  of  importance  in  these  calculations.  Moreover,  the  situation 
of  the  point  B*,  or  of  the  arc  B  B"  is  indeterminate,  when  the  points  B,B",  coincide  ;  or 
are  in  opposite  parts  of  the  spherical  surface  ;  we  must  therefore,  for  the  same  reason,  avoid 
the  use  of  observations,  where  the  geocentric  positions,  in  the  first  and  last  observations,  are 
very  near  to  each  other,  or  are  very  nearly  in  opposite  parts  of  the  heavens.  We  shall  also 
exclude  this  case  from  our  calculations.  It  is  important  to  observe  that  the  geocentric  and 
heliocentric  places  of  the  comet,  in  any  particular  observatioii,  fall  on  the  same  side  of  the 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  875 

[5999] 
ecliptic;  the  latitudes  being  cither  both  north,  or  both  south;    moreover,  the  heliocentric 

place  of  the  planet,  is  always  situated  in  a  point  of  that  part  of  the  arc  of  the  great  circle, 

which  is  included  between  the  geocentric  place  of  the  planet  and  the  heliocentric  place  of  the  noiiocen- 

trie   dI&cc 

earth.     Thus,   in   the   first  observation,  the  hehocentric  place  of  the  planet  C,  is    situated  «(  the 

'                               '  planet. 

between  the  heliocentric  place  of  the  earth  A,  and  the  geocentric  place  of  the  planet  B  (2) . 
This  will  be   evident  from   the  following  considerations.     If  the  planet  be  at  an  infinite 

distance  from  the  earth,  the    point  C  will  evidently  fall   infinitely  near  to  B  ;  and   if  that  (vj 
distance  be  infinitely  small,  the  point  C  will  fall  infinitely  near  to  A.     Moreover,  it  is  plain, 
that  if  we  suppose  the  situations  of  the  sun  and  earth  to  remain  unaltered,  while  the  distance 
of  the  planet  from  the  earth  a  a,  figure  84,  page  792,  increases  in  the  direction  of  the  line 

«a',  from  nothing   to  infinite,  without  altering  the    geocentric  position  of  the   planet  in  the  (7,^ 
heavens,  or  the  position  of  the  line  a  a!  ;  the  heliocentric  place  C,  figure  92,  will  gradually 
move  from  A  towards  B  ;  which   are  the  two  extreme  points  or  limits  corresponding  to  an 
infinitely  small,  or   an  infinitely  great  distance  of  the  planet  from  the  earth  ;  therefore,  the 
point  C  will  always  fall  between  A  and  B.     Hence  we  shall  have, 

CB^ABKISO";        C'^'<^'JS'<  180'^   or  2<5',  (30,  24)  ;         C"5"<^"jB"<  180".  (sj 

In  the  calculations  of  this  article,  we  shall   use  the  following   symbols,  which  are  similar  to 
those  in  [5995—5997]. 

Sytiibols. 

t,t',t",           Times  of  observation  ;  (9) 

©.  ©'.  ©".     Longitudes  of  the  Sun  ;  (lOj 

A,  A',  A",        Longitudes  of  the  earth,  differing  180'*  from  ©,  ©',  ©",  respectively  ;  (11) 

O.,  a.',  O.",          Geocentric  longitudes  of  the  planet  ;  ('2) 

6,  6',  6",           Geocentric  latitudes  of  the  planet  ;  southern  latitudes  heing considered  as  negative;  (13) 

a*,  6*,             Geocentric  longitude  and  latitude  of  the  point  B*;  southern  values  of  the  latitude  6*  being  negative;  03', 

R,  R',  R",       Distances  of  the  earth  from  the  sun  ;  (M) 

Pi'f/'ti"'         Distances  of  the  planet  from  the  earth  ;  (15) 

f,  />',  f",            Curtate  distances  of  the  planet  from  the  earth  ;  (16) 

r,r',r",           Radii  vectores  of  the  orbit  of  the  planet  ;  (17) 

y8,  yS', /2",           Heliocentric  longitudes  of  the  planet  ;  (18) 

OT,  Œ-',  isf",       Heliocentric  latitudes  of  the  planet  ;  southern  latitudes  being  considered  as  negative  ;  (19) 

V,  v',  v",           True  anomalies  of  the  planet  ;  (ao) 

u,  u',  u",           Arguments  of  latitude  of  the  planet,  or  distances  from  the  ascending  node,  counted  on  the  orbit  ;  (21) 

CC'C",          C=angle  G'CS;         C  =  angle  G'C'B' ;         C"=  angle  G'C"£";  (22) 

w,w',  w".        Arguments  of  latitude  of  the  planet,  reduced  to  the  ecliptic,  and  counted  from  the  ascending  node  ;  (23) 

i,î',i",          i  =  -i.\-cAB;         i-i  =  3rcA'B';        J- "  =  arc  A"  B"  ;  (24) 

i*                    i*  =  ATC  B'B*;  (25) 

n,                       Longitude  of  the  ascending  node  of  the  orbit  of  the  planet  ;           u  =  180"*  -|-  n  ;  (2(5) 

J,                       Inclination  of  the  orbit  of  the  planet  to  the  ecliptic  ;  (27) 

E,E',E'i,     E  =ans\eA'EA"  ;        £'  =  angle  .«JEVÎ"  ;        E"  =  angle  AE"A' ;  (28) 

7f,2f',2f",     2/=arc  C'C"  =  »"—»';         2/' =  arc  CC"  =  »"— o  ;         of  "=  arc  CC  =  v' —  v  :  (29) 

z,z'                   2  =  arcC'B';         z' =  arc  C'fi*  =  arc  C'2î' —  arc  £'£•  =  2 —  .f»,  (25)  ;  (30) 

^,  f  "  f  =  arc  CE'  ;        C  =  arc  CE'  ; 


(31 J 


876 

[5099] 

(32) 

Formulas 

uaedin 

(33) 

these   cal- 

culations. 


APPENDIX,  BY  THE  TRANSLATOR; 


6  = 


R.sin.fsin.jAiiE'—J-i')  . 
RiiMn.<f".sin.{JlE'—S}  ' 
i{'.sin.J'.sin.(.^"£— J") 


C34)       c  = 


(35)        d  = 


(36) 
(37) 

(38) 
(39) 
(40) 

(40-) 

(41) 
(41') 

(41") 
(4J"'/ 

(42) 

(43) 

(44) 

(45)  x('_ 

(46)  X  = 


2iî'3.siu3.<f'.sin.J-« 

b.sec.S''  —  a  _ 

i^sic.J"*—  I  ' 

tang-iT* 


t  Assumed  1 
value  of  a.  J 

r  Assumed  "I 
Lvalue  of  b.J 

[Assumed  1 
value  of  C.J 

[Assumed  "1 
value  of  d.  J 

t  Assumed  'I 
value  of  C.J 


"—  b.sec.'f—i  ' 

[rr'],  [r'  r"],  [r  »"],     represent  as  in  [5994(266)],  the  double  ol   the  areas  of  the  plane  triangles  sab,  she,  sac, 

in  figure  84,  page  792,  respectively.     The  radii,  corresponding  to  any  particular  triangle, 

being  included  between  the  brackets  ; 


^  I  [»■  r"J  '5 

tang,  w 


sin.J"  " 


{P4-a.).e         ,  ,  ,, 

„    ,  — =-^^ ■ — —  ;       ('30') 

(;-±-:)_eos...        ^  +  ^ 


6/^+' 


+ 
Q'  =  c  Q.sin.  w  ; 

Q'.sin4.z  =  sin.  (2— w  —  <r")  ;  or,         ([26) 

o  =  log.  Q'  +  4. log.  sin. 2  —  log  sin.  (z  —  w  —  <f  *)  ; 

['•'-"]       ,_(P  +  a).g.sin.J-' 

[r';-"J  ■               b.sm.{z  —  i*)  ^       ' 

I  [,'  r"]   ■        5    "  P  ■■ 


[First  unknown"! 
quantity   P.   J 

t Second  unknown"] 
quantity  Q.      J 

t   Assumed  "I 
value  of  W.J 

[Assumed   1 
value  of  Q'.J 


[>•  ''] 


(■69) 


_  Jî.sin.J.  sin.  (./?'£"  —  J-'  -f  J  *)_  a  . 
'  jR'.  sin.cf'.sin.(^-E"  — cf)      ~  6"  ' 

6,.  sin.J-» 

if.sin.J" 


(i33') 


sia.(.^£'  — <r)  ' 

B".sin.<f  " 

'sin.(.^"£'  — J"') 

cos.(.^£'— J-) 


-  ;    whence    a=^;      (32,44,45) 


(47) 

(48) 

(49) 

(50) 
(51) 
(52) 

(53) 

(54) 


i?.sin.<f 

cos.(.^"£'_J") 

~       ii".  sin.J'" 

C  [r  r"]      ,  }      sin.E 
=    <  =—. — 7TZ  .  r 


J  [»■''■"]■     S 


sin.£' 


sin.(î  +  ^'£  — ,r');     (182) 


•^         llrrn         5      sin.B'  ^   ^ 


[Assumed   "| 
value  of  bf.j 

[Assumed  T 
value  of  Wj.J 

[Assumed  "1 
value  of  «.J 

[Assumed   "I 
value  of  x".  J 

[Assumed  '1 
value  of  x-J 

[Assumed  "i 
value  of  X".  J 

t   Assumed  ~| 
value  of  p.  J 

[Assumed    "1 
value  of  p".  J 

[Assumed  "1 
value  of  q.  J 

[Assumed  ~l 
value  of  q",  J 


.[rr'] 
q  =  x..(\p— I);    (igS) 

q"  =  «.".  (x"p"— I);      (198) 

p=r.sin.,>-;       q  =  i-.co3.f;         (182,195);  tang.f=^;         r  =  p.cosec.f  =q.sec.f  ; 

P" 
p"=r".sin.^";        q"  =  r".  cos.f  "  ;  (181,198);         tang.f"=^;         T"  =  p".  cosec.^"  =  q".sec.^"  ; 

log.  k  =  8,23558:4  ;    [5987(8)]- 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  877 

[5999] 
The  points  B,B',B",  are   given  by  observation,  also   tlie  points^,./!?',.//",  by  tiie   solar 

tables  j  and  when  they  are  connected  by  2;reat  circles,  as  in  figure  92,  we  shall  have  several    '^*'' 

spherical  triangles,  whose  sides  and  angles  can   be  computed,  by  the  common  processes  of 

spherical   trigonometry  ;  frequently  using,  with   much  advantage,   the   formulas  of  Napier 

[1345,^^'^^''"'^'].     Gauss  has  given   many  other  similar   formulas,  but  it  is  not  necessary  to 

repeat  them  here,  because  the  computations,  by  the   usual   methods,  are  in   general  more 

simple,  short,  and  accurate  than  those  in  whicii  many  auxiliary  angles  are  introduced  ;  since 

the  small  fractional  parts  which  are  neglected  in  these  auxiliary  angles,  may  have  a  tendency 

to  produce  small  errors  in  the  results.     We  shall  now  give  the  enumeration  of  the  triangles 

which  are  to  be  computed,  inserting  some  of  the  formulas,  to  which  we  may  have  occasion 

to  refer. 


(56) 


(57) 


First.     From  the  point  B,  draw  the  arc  Bb,  perpendicular  to  the  arc  A  G  ;  tlien  in  the 
rectangular  triangle  AbB,  we  have  the  perpendicular  Bb=ô=  the  geocentric  latitude  of    .^g, 
the  planet  at  the  first  observation  ;  and  the  base  Ab=o. — A=^  the  difference  of  longitudes 
of  the  points  B,A;  whence  we  find  the  angle  BM^j,  as  in  the  first  of  the  formulas  (62),    '*'' 
which  is  the  same  as  [1345"];  and  the  hypothenuse  &,  asin  the  first  of  the  formulas  (63),  which    ^^yj 
corresponds  to  the  second  of  [1345  -'].     In  like  manner,  by  letting  fall  perpendicular  arcs. 


First 


from  the  points  B',  B",  upon  the  arc  AG;  we  may  form  similar  triangles,  corresponding  to    ?'""«• 
the  second  and  third  observations  ;  from  which  we  may  deduce  the  values  of    ■)-',  y",  S',  è", 
(62,63)  ;  or  they  may  be  more  simply  derived  from  the  expressions  of    y,  6,     by  merely 
accenting  the  letters,  to  correspond  to  the  particular  observations.     The  values     ô,  à',  ô", 
are  always  considered  as  positive. 


(Cr)') 


(01) 


tang.d  tang.ô'  tang.â" 

tang.7  =    ■     ,         .-  ;  tang.y  =  ^-— — —  ;  tang.7  =  -r~-j — —  ;  (ga, 

sm.(a — .^)  sm.(o.' — A)  sm.(a — A) 

tang.(a— ^)  tang. (a' — A')  „,       tang. (a"— ^") 

taBZ.S=   -^-^ ';  tang.(5'  =  — ^ ; -' ;         tang.5"== — ^-^^ '.         (63) 

COS.7  cos  .7  COS.7 

We  shall  suppose,  that  neither  of  the  expressions  of    tang.7,     '«^ng-y'»     ••^"g->")     appear 
under  the  form  §,  in  the  observations  which  have  been  selected  for  computing  the  orbit.  (^'') 


Second.  In  the  triangle  A  A'E",  we  have  the  angles  A'AE"=  y,  AA' E"  =180"— y' , 
and  the  side  AA'=A'—A  ;  to  find  by  Napier's  formulas  [1345 «.^i],  the  sides  AE",  A'E"; 
and  then  the  angle  E",  by  [1345'*],  or  ^E"  by  [1345 '«or  1345"].  In  like  manner,  in 
the  triangle  AA"E',  we  have  the  angles  A"AE'=7,  AA"E'=  180"— >",  and  the  side 
AA!'=A!' — A;  to  find  by  the  same  formulas,  the  sides  AE',  A"E',  and  the  angle 
AE'  A"  =  E'.  Lastly,  in  the  triangle  A' A'E,  we  have  the  angles  A"A'E=y, 
A'A"E=\80"—'}",  and  the  side  ^'^"=  ^"— ^' ;  to  find,  by  the  same  formulas,  the 
sides  A'E,  A'E,  and  the  angle  E. 

VOL.  III.  220 


Second 
process. 

(65) 
(66) 

(67) 


878 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5999] 

Thud 

process. 
(68) 


(68') 


(69) 


(70) 


(71) 


(72) 


(74) 


(73) 


(76) 


(79) 


Fourth 

proccsa. 

(80) 


(81) 


(89) 


Third.  To  find  the  point  B*  ;  we  have  given,  in  the  triangle  i?£'B",  the  side 
BE'=AE'—AB  =  AE'—5,  the  side  B"E'=A"E'—A"B"=A"E'-o",  and  the 
angle  BE'B'=  E'  ;  to  find  the  angles  EBB",  E'B'B,  by  Napier's  formulas  [1345«.«], 
and  the  side  BB",  by  [1315'*].  Then  in  the  triangle  BE"B*,  we  have  given,  the  angle 
BE"B"=E",  the  angle  E"BB*=E'BB",  and  the  side  BE"=AE"—AB=AE"-Ô; 
to  find  the  sides  55»,  B*E",  by  Napier's  formulas  [1345™'5i],  and  the  angle  BB*E",hy 
formulas  [1345'='].     Finally,  we  have  B*B"^BB"—  BB*  ; 

B*B'=  B*E"—  E"  B'=  B*E"—  A'E"  +  A'B'=  B'^E"—  Jl!E"-\-  Ô'. 


In  the  plane  triangle  STC^,  figure  87,  page  793,  the  sides  TC,,  ST,  S  C, ,  or  the 
corresponding  symbols  p,,  R,  r,  are  respectively  proportional  to  the  sines  of  the  opposite 
angles  TSC^,  SC^T,  STC^  ;  and  these  angles  are  represented  in  figure  92,  page  874,  by 
the  arcs  AC,  CB,  180'' — AB  ;  as  will  evidently  appear,  if  we  suppose  in  figure  87,  page 
t")  798,  a  line  SB  to  be  drawn  through  S,  parallel  to  TC,,  and  continued  infinitely,  in  the 
heavens,  towards  this  point  which  is  marked  B,  in  figure  92  ;  so  that  we  shall  have,  in 
figure  87,  the  angle  j9;S'C^=  angle  SC^T;  and  the  lines  SC^,  ST,  being  continued  infinitely , 
fall  iu  the  points  C,  A,  figure  92.     Hence  we  have. 


sin.^C      sin.CB       s'm.AB 


P, 


R 


From  these  we  obtain  the  expressions  of  r,  p^  (77,  78)  ;  and  by  accenting  the  letters  we 
get  the  similar  quantities  corresponding  to  the  second  and  third  observations,  using  the 
symbols  (24,30)  ; 


r=  R 


s'm.AB         R.sia.5 


r'=z  R'. 


sm.A'B' 


R'.sm.ô'        R'.sm.ô' 


(77) 


(78)         P, 


sm.CB         sin.  CB'         '       " 'sm.  CB'         sm.C'B' 
,.       R".  sm.A'B"         R".  sin. 5" 


sjn.s 


sm.CB" 


sm.CB"- 


R 


sm.  AC 
sm.CB' 


,_       sin.^'C  _  R'.sm.{ô'—z)_ 
sm.Czï  sm.z 


R". 


s\n.A"C" 

sm.CB"' 


Hence  it  is  manifest,  that  when  the  situations  of  the  points   C,  C,  C"  are  known,  we  can 
determine  the  values  of    r,  r' ,  r"  ;     p^,  />/,  p/'. 

Fourth.  We  shall  now  show  these  points  C,  C,  C",  can  he  determined  by  means  of  the 
quantities  P,  Q  (38, 39).  We  shall  suppose  M  to  be  the  point  of  intersection  of  tlie  great 
circles  B"B*B,   C'C'C,  and  for  brevity  we  shall  put, 

2f=  arc  C'C'^MC  "—  M  C  =  v"—  v'  ;  2/'  =  arc  C  C"=  M  C"—  M  C  ^  v"—  v  ; 

2f"=  arc  CC  =MC'  —  MC  =  v'—  v  ; 


(82)     observing  that  <Ae«c  symbols  have  the  same  symmetry  relative  to  the  number  of  accents,  in 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  879 

[5999] 
f,f\f'';  C'C",  CC",  CC;    as  in  the  similar  expressions  [5994(279')]  ;  moreover,  the     («a") 

values  of    /,/',/",    in   terms  of    v,v',v",     are  the  same   as   in   [5995  (13  &.c.)]. 

Tlie  equation  [5994(278)]  is  founded  upon  the  supposition  that  the  three  places  of  the  planet  '^^  ' 
or  comet  a,  b,  c,  figure  84,  page  792,  are  situated  in  the  same  plane,  passing  through  the  sun, 
which  is  the  origin  of  the  rectangular  co-ordinates  x,y,  z;  but  the  plane  of  xy,  and  the 
direction  of  the  axis  x,  are  wholly  arbitrary.  Now  if  we  take  the  plane  of  the  orbit  for  that 
of  xy,  it  will  be  represented  in  figure  92,  page  874,  by  the  plane  drawn  through  the  centre 
of  the  sphere  S,  and  the  great  circle  M  C  C'C"  ;  and  if  we  take  the  line  SM  for  the  axis 
of  X,  and  the  line  perpendicular  to  it,  in  the  same  plane,  for  the  axis  of  y,  we  shall  find  that 
the  radii  r,  r,  r",  form  with  the  axis  of  cr,  three  angles  which  are  represented  by  the  arcs 
MC,  AW,  MC",  respectively  ;  therefore,  by  the  usual  rules  of  trigonometry,  we  shall 
have, 

x  =  r.cos.MC;  x' ^r'.cos.MC  ;         x"  =.r" .cos.MC" ; 

y=r.sm.MC;  y' ^r'.sm.MC  ;  y"  =r".sm.MC". 


(83) 
(84) 

(85) 
(80) 

(86') 

(87) 
(88) 


Substituting  these  values  of    y,  y',  y"     in  [5994(278)],  we  get, 

0  =  [/  ;"].r.sin.MC  —  {rr"\r'.sm.MC'  +  [r/J.r".  sm.MC"  ;  m 

and  by  comparing  [5994(300')],  with  (S2),  we  obtain  the  following  expressions,  which 
have  the  same  symmetry,  in  the  accents  as  in  (82')  ; 

[rr']  =3  r  r'.sin.2/"  ;         [r'/']  =  r'r".  sin.2/;  [rr"]  =  7-)".sin.2/' .  m) 

Substituting  these  last  expressions  in  (89),  and  dividing  by  rr'r",  we  get  (91),  which  is 
the  same  as  (92),  using  the  values  of    2/,  2/',  2/"     (82)  ; 

0  =  sin.2/.sin.;tf  C  -  sin.2/'.  sm.MC  +  sin.2/".  sm.MC"  ; 

0  =  sin.C'C".sin.J»/C  — sin.CC'.sin.MC'+sin.CC'.sin.^WC". 

This  may  be  considered  as  a  theorem  in  spherics,  signifying  that  the  points  C,C',C", 
are  situated  in  the  same  great  circle  MCC'C"  ;  M  being  any  point  whatever  of  the 
circumference  of  this  great  circle.  If  we  suppose  the  point  M  to  be  placed  on  the 
continuation  of  the  arc  CM,  of  the  great  circle,  so  as  to  increase  the  distance  CM, 
by  the  quantity  90^  the  term  sm.MC,  will  change  into  sin. (MC+  90''),  or  cos. MC, 
and  the  other  terms  of  the  equations  (91,  92),  being  changed  in  the  same  manner,  we  get, 

0  =  sin.2/.cos.MC  —  sin.2/'.  cos.MC  +  sin .2/".  cos.iliC"  ;  (93) 

0  ^  sin.  C'C".  cos.AJC  —  sin.  CC".  cos.MC  +  sin. CC.  cos.JiC",  (93) 


(91) 

m) 

Theorem 

m 
sphericit. 
(92') 


(92) 


tvhich  is  merely  another  form  of  the  theorem  in  spherics  (92).  We  shall  now  suppose  that 
perpendicular  arcs  of  great  circles  are  let  fall  from  the  points  C,  C,  C'',  £,  E',  E",  upon  '^''' 
the  great  circle  J/2?B''E/ ;  the  arcs  C^C,  l!^/-Ë',  are  the  only  ones,  which  are  actually  drawn  (95i 
in  the  figure  ;  the  others  being  omitted,  to  avoid  confusion.     We  shall  represents  these  arcs, 


Theorem. 


880  APPENDIX  BY  THE  TRANSLATOR  ; 

r 59991 

(96)  by  the  Roman  capital  letters  C,  C,  C",  E,  E',  E",   respectively.     Then  in  the  rectangular 

spherical  triangle  MCC,  we  have,  as  in  [1345='],  the  first  of  the   following    equations,  or 

(97)  the  value  of  sin. C,C  or  sin.C  ;  the  second  and  third  of  these  equations  correspond  to 
the  points  C,  C",  and  are  easily  derived  from  the  first,  by  increasing  the  number  of 
accents  ; 


(98) 


sin.C  =  sin. CMC,.sm.MC  ;     sin.C'=  sin. C;iiC^.sin.;V/C"  ;     sin.C"=sin. CMC^.sm.MC" 
Substituting  these  in  (89),  after  multiplying  it  by  sin.  CMC,,  we  get, 

(99)  0=[rV"].r.sin.C— [rr"].7-'.sin.C'+  [rr'].r".  sin.C". 

In  the  right  angled  spherical  triangles  E'E^'B,  CCB,  we  have,  by  [1345  ='], 

(100)  sm.E'E;=  sm.E'BE;.  sm.BE'  ;         sin.  CC,=  sin.  CSC  .sin.  CB. 
Dividing  the  first  of  these  expressions,  by  the  second,  and  observing  that, 

sm.E'BE;  =  sïn.CBC,, 


we  get. 


(101) 


whence  we  obtain, 
(loi'i  sin.  CC,= 


sin.E'E;         sin.-BE'   _ 
sin. CC,    ~  sin.CB    ' 

sin.E'E,'.  sin.  CJ5 


sin.BE' 
substituting, 

(102)  BE'=^AE'  —  AB  =  AE'—Ô:  E'E;=E';  CC,  =  C, 

(103)  W6  g^*^  the  first  of  the  equations  (105)  ;  and  by  adding  another  accent  to  the  letters  E',E', 
we  get  the  second  expression  (105),  corresponding  to  the  point  E".     In  exactly  the  same 

(104)  way,  we  obtain  the  values  of    sin.C  (106),  and     sin.C"  (107). 

.    ^      sin.E'sin.Ci5  sin.E".  sin.Cl^ 

(105)  sin.C= 


(106) 


.C'= 


sin.(^E'-^)  sin.(^E"— (5)  ' 

■  sin.E.sin.  C'B*  sin.E".  sin.C'B* 


(107)  sin.C"= 


sin.{A'E-&'-\-o*)         sm.{A'E"—à'-\-è*)  ' 
sin.E.sin.  C"B"  sm.E'.sm. C"B" 


sm.{A"E—ô")  sm.(A"E'—ô") 


Dividing  the  first  of  the  equations  (105),  by  the  second  of  (107),  we  get  the  first  equation 
(108)  ;  in  like  manner,  by  dividing  the  fii-st  of  the  equations  (106),  by  the  first  of  (107), 
we  get  the  second  equation  (108)  ; 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  881 


sin.C  _   sin.C^      sin.(^"-E'— ^")  sin.C'_sin.C".B*     sm.{A"E—è") 

sm.C"~~  sm.C'B"'   sm.{AE'—&)''  ^i^'~sin.C"B"  "  sm.{A'E—5'+  Ô*)  '  '"*' 

Dividing  the  equation  (99)  by     ?■".  sin.C",  and  substituting  (108),  we  obtain, 

^     ^  ,  „.     r.sm.CB      s\n.{A"E'—ô")  „    r'.sin.C'B*      sm.{A"E  —  ô")      ,    ,    , 

'=f''  '"  ^-.".sin.C'ii"  •  sln.iAE'-ô)  "  t'''  ^V'.sin.C'i?"  "  sin. (^'£-.5'+'^*)  +  ^"  ^^        '"" 

Substituting  tlie  values, 

r.sin.C5  =  iî.sin.â;         r'.sin.C'B' = /J'.sin.â' ;  r".  sin.C"B"=  jR".  sin.^"     (77);      (ho) 

observing  also  that  sin.C'5*  may  be  put  under  the  form, 

sin  C'B*  sin  '' 

sin.C'B*=sin.C'£'.         ^ o>  =  sin.  C'B'.  -^^  ;     (30),  (ni) 

sm.C'^'  sin.z       ^     ' 

we  get, 

n—r/  •"!    ^-^'"-^     sin.(^".E'  — j")_  il',  sin.6'        sin.(.^"i:  -  Ô")      sm.z' 

^-^  '  -'■iî".sin.o"-  sin.(^£'-<5)       ^'''  -"-ii".  sin.o"  '  sm.{A'E-ê'+ô*)  '  iii^  +  '^'"'"^  '      '"'^ 

and  if  we  use  the  assumed  values  of    a,  b,  (32,33),  it  becomes, 

sin.js/ 

0  =  a  .  [/)•"]  —  [7  r"]  .  b . 1-  \rr'\ .  (ii3) 

sin.s 

From  the  assumed  value  of    P     (38),  we  easily  deduce. 


[5999] 


substituting  these  in  (113),  we  obtain. 


hence  we  get, 


r-\- 1  sm.z 


[rr<]-\-[fr"]      P+ 1       sin.s' 


[,T"]  P-\-  a      sin.z 

g  this,  and  the  i 
we  obtain. 


(114) 


(115) 


(116) 


Substituting  this,  and  the  value  of    r'= — 'r—^     (77),  in  the  assumed  value  of     Q    (39);     ("^) 


C  P+1       sin.z'  )     /î'3.  sin3.<5' 


^  ^  P  +  a       sm.2  5 


(118) 


sin^.z 


Multiplying  this  by     ^^^-^^„     we  get, 
VOL.  III.  221 


882  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5999] 

q.sm\z  P+l 

(119)  — rr^- ~ —  =  b  .  — .  Sin. S  — sin.z. 

2iî'3.siiA6'  P  +  a 

Now,  from  [21]  Int.,  we  have,  by  using     z  =  z'-{-  &*     (30), 

(120)  sin.z  =  sin. (z'4-  <5*)  =  sin.s'.cos.(5*-|- cos.z'.  sin.é*  ; 

substituting  this  in  the  last  term  of  (119),  we  obtain, 

Q.sm'^.z  C     P+ 1  ) 

(•*"  ^^^- —  =  <  b.— C0S.5*  >  .sin.z' — sin.i5*.cos-.z'. 

2iî'3.  sin3.  S'        I     P+  a  3 

The  assumed  value  of  the  first  expression  of    tang.w     (40),  gives, 

/P-(-l\  sin. (5*        sin.rP.cos.w 

(122)  b  .    -fr-, —  )  —  cos.(5*  = = : . 

\P-f-a/  tang.w  sin.w 

Substituting    this    in   (121),  we  get   (123)  ;    thence   by  successive   reductions,  and   the 

(123)  re-substitution  of    z'  =z—S*     (30),  we  obtain  (125)  ; 


©.sin^.z 

(123)  ^ 


s  .       ^         (   COS.W        .  ) 

--  =sm.o*.  < .sin.z' — cos.z'  > 

.  i5'  I  sin.  w  ) 


2/î'3.sin3 

sin.5*    ,  .  .  ,,       sin.6» 

(124)  =-: .jcos.w.sin.z' — sin.w.cos.z'{=  -: .sin.fz  —  w) 

sin.w  sin.w 

sin  (5* 

C^'  =--- .sin.(z— w— 5*). 

sin.w 

Multiplying  this  last  expression  by     — ^ ,     and  substituting,  in  its  first  member,  the  assumed 
value  of    c     (34),  we  get, 
('25')  c  Q.sin.w.sin^.  z  =  sin.(z  —  w  —  i5*)  ; 

Funda- 
mental 

equation    and  by  using     Q'    (40'),  it  becomes, 

(126)  Q'.sin^.z  =  sin.(z  —  w  —  Ô*)  ; 
or  by  using  logarithms, 

(126')  log.  Q'  +  4.1og.sin.z  —  log. sin. (z  —  w  —  6*)  =0; 

from  which  we  must  find  the  value  of  the  unknown  quantity    z.     We  may  observe  that  the 
assumed  value  of, 

sin.o 

(127)  tang.w  =  — T^XK ~     ('**^)' 

cos. 5* 


\P+aJ 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  883 

[5999] 
may  be  rendered  more  convenient  for  calculation,  in  the  following  manner.     Multiplying  the 

P-L.  a 
numerator  and  denominator  by     — ,     it  becomes, 

(f +a).tang.6* (P-j-a).tang.3* 

tang.w—  J  3ec  ,s#  (p_)_j)_(p_(_3)  —  p  (i.sec.<5*— 1)  +  (6.sec.<5*  —  a)'  '"*' 

Substituting  in  the  numerator,  the  expression, 

tang.  5*  ^=  e.  (b.sec.6*  —  1),  ("a») 

depending  on  the  assumed  value  of    c     (36)  ;  and  in  the  denominator, 

b.secA*  —  a  ^  (h.secà*  —  l).c/, 


(130) 


depending  on  the  assumed  value  of  d  (35),  we  find  that  the  whole  numerator  and 
denominator  becomes  divisible  by  b.sec.i*—  1,  and  we  finally  obtain  the  second  expression 
of    tang.w     (40),  namely, 

(P+a).e 
tang.w  =  ^  J    '    .  (130') 

F-\-a 

The  calculation  of  the  quantities  a,  J,  c,  d,  e  (32 — 36),  which  depends  on  known  quantities, 
constitutes  the  fourth  operation.     The   actual  values  of     b,  c,  e,     are  not   required,  but 

merely  their  logarithms.     If  we  put     -3=6,,   and  substitute  the  values  of  a,  i    (32,33), 

we  find  that  the  factor  i?".sin.5"  occurs  in  the  numerator  and  denominator,  and  by 
rejecting  it,  we  get  the  following  expression, 

■R.sin.^     sin.(v4"-E'— d")    sin.(.^'-E— ^'+ 6*) 
'~'R'.sm.ù''sm.{A"E-&")'       s\n.{AE'—lj       '  "^''* 

Now  from  the  second  and  third  forms  of  the  equation  (107),  we  get  (132)  ;  from  the  second 
and  third  forms  of  (106),  we  get  (132')  ;  and  from  the  second  and  third  forms  of  (105),  we 
get  (132')  ; 

sm.(A"E'—S")         sin.E' _ 


sm.{A"E—ô")         sin.E 
sin.E 


(132) 


sin.(A'E  —  r/+  6*)=-:— -,.sin.(./2'£"— o'+o*);  (m) 

sm.E 

1  _  sin.E"  1 

sm.{AE'—ôy^  sin.E' " s\n.{AE"—S)  '  "^"' 

Multiplying  these  three  expressions  together,  and  rejecting  the  factor     sin.E.  sin.E'. sin.E", 
which  occurs  in  the  numerator  and  denominator  of  the  second  member,  we  get, 

sin.(^"£'— é")   sh.(A'E  —  è'+  6*)      s\n.(A'E"—o+  6*) 

sm.(A"E—Ô"y      s\n.{AE'—5)      ~       sm.{AE"—ô)       '  "^" 


B84 

[5999] 


APPENDIX,  BY  THE  TRANSLATOR; 


Substituting  this  in  the  second  member  of  (131'),  we  obtain  the  value  of    h,     (42),  satisfying 


(133')    the   equation     h,  =  T-,     or     a  =M,     (131). 


(133"i 

Special 
cases. 


(134) 


(135) 


(136) 


(137) 


(138) 


(138') 


(139) 


(W»") 


(140) 


(141) 


(142) 


There  are  two  special  cases,  where  some  modification  must  be  made  in  this  calculation. 
The  Jirst  is  when  the  great  circles  BB",  A"B", 
coincide  ;  as  in  the  annexed  figure  93  ;  in  which  the 
point  B  coincides  with  E',  and  B*  with  E.  In  this 
case,  the  quantities  a,  b  (32,33),  become  infinite, 
because  the  factors, 

sin.(^  E'—  Ô),         sm.{A'E—S'+  6*), 

which  occur  in  the  denominators  of  these  values  of 
a,  b,  vanish.  When  this  happens  we  must  divide 
the  equation  (113),  by  b,  and  substitute  the  assumed 

value  of    r=^/    (133'),  and     2=2  — <i*    (30),     A 
also    —^  =  0.     Hence  we  get, 


0  =  b,.[r'r"]-''''-^'-^*\[rr"]. 


sin.;! 


Multiplying  the  numerator  and  denominator  of    tang.w   (40),  by    b,,  it  becomes,  by  putting 
as  in  (133')     bb,  =  a, 


tang.w  = 


b,  .sin.^* 


{P -{-!)— b,.cos.ô* 


P  +  a 


and  as     a     is  infinite,  the  denominator  is  equal  to     P+l — è,.cos.5*;     consequently  this 
value  of    tang.w,     becomes  the  same  as  the  expression  of    tang.w,     (43). 

The  second  case  is  where  ô*  =  0.  Then  the  expression  c  (34),  is  infinite  ;  and 
w=;0  (40);  hence  it  would  seem  that  the  factor  c.sin.w  (125'),  becomes  indeterminate. 
But  if  we  multiply  together  the  expressions  of  c,  tang.w  (34,40),  and  the  product  by 
cos.w=l,  we  get,  by  rejecting  the  factor  sin.5*,  which  occurs  in  the  numerator  and 
denominator, 

1 


c.sin.w  : 


2iî'3.  sm\ô'  .  U .  ( J^)  —  cos.S*  \ 


Multiplying  the  numerator  and  denominator  by     P-{-a,     and  substituting     cos. 5*  =  1 , 
we  get, 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  886 

[5999] 
P+a 

2jK'^  sin"*.» .  I  o.{F-\-l) — r — a  { 

l a 

Now  when   cos.(S*=l,  the  expression  of  d   (35)  becomes  d=j — r,or6 — a=tZ.(6 — 1);    ci44) 

consequently, 

è.(P+l)-P— a=(è— l).P+(i— a)=(6— l).P-}-f/.(è— l)=(i— l).(P+rZ).  (hs) 

Substituting  this  in  (143),  and  then  multiplying  by     Q,     we  get  for     Q'     (40'),  the 
following  definite  expression  ; 

„,       „   .  (P+a).Q 

(e=c(e.sm.w=  2R^sinW. {b—l).{P+d)  '  ("") 

Lastly,  substituting     â*  =  0,     and     w=iO     (140),  in  the  second  member  of  (126),  we 
find  that  the  whole  equation  becomes  divisible  by    sin.  s;     then  substituting  the  expression    <'■"' 
of    Q     (140),  and  extracting  the  cube  root,  we  get,  in  this  second  case. 

Fifth.    When  P,  ^,  arelcnown,  we  can  obtain  \\  from  {AO),  and  then  z  from  the  equation   (ns) 
(41  or  41').     In  a  first  approximation  we  may  assume  for     P,    Q  the  values      P',  Q'   rmh 

process» 

(259)  ;    and  by  repeated  processes,  in  the  manner   explained  in   (259 — 267)   we  can 
compute  the  true  values  of    P,  Q  ;    from  which  we  finally  deduce   the  required  value  of  (150) 
z.    If  we  develop  the  second  member  of  (41),  by  [22]  Int.  ;  it  may  be  put  under  the  form, 

Q'.  sin^2  —  COS.  (w  -\-  â*).sin.r  = —  sin.(w  +  5*).cos.z  ;  (isi) 

squaring  this  equation  and  substituting   cos^.2  =1  —  sin^.z,    it  produces  an  equation  of  the 
eïg-^iA  degree  in    sin.  s  ;    which  according  to  the  general  theory  of  equations  may  have  eigfAf   (iss) 
roots,  real  or  imaginary.     Several  of  these  roots  must  necessarily  be  real,  and  they  may  all 
be   very    quickly    found,   by  supposing     sin.~     to  increase  gradually  from     0  to  1,     and    ('53) 
selecting,  by  inspection,  those   values   which  nearly  correspond  to  this  equation  ;  and  then 
by  a  few  operations,  correcting  these  first  assumed  quantities,  so  as  to  get  the  precise  values 
of    z     which  satisfy  it.     We  may  reject  all  the  negative  values  of    sin.  z,     because  they    (154) 
would  make     r'     (77)  negative,    ^'     being  supposed  positive  (61)  ;    we  must  also  reject 
those  in  which     z     exceeds     5'     as  is  evident  from   (8)  ;  and  also  from  the  consideration    (155) 
that  if    sin. ((5' — z)    were  negative,  it  would  render   p',  (78)  negative.     When  the  intervals 
of  the  times  are  moderate,  it  is  generally  found  that  there  are  four  values  of    sin.  z,     which 
satisfy  the   equation,  of   which  one    is  most    commonly   negative,   and    can    be  rejected  ;   (i56) 
sometimes  there  are  three  negative  values,  and  only  one  positive  value,  consequently  there 
is  then  no  ambiguity  as  to  that  which  is  to  be  used.     In  case  of  having  three  positive  values, 

vor,.  III.  222 


886  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5999] 

it  commonly  happens  that  one  of  them  is  very  nearly   equal  to     (5'.     This  value  satisfies 

(157)  the  analytical  conditions  of  the  problem,  but  not  the  physical  conditions.     The  analytical 
conditions  require  that  the  planet  should  be  situated,  at  the  times  of  the  three  observations, 

(158)  somewhere  on  the  lines      a'a,  b'b,  c'c,     fig.  84,  page  792,  respectively,  and  that  the  selected 
points     a,  h,  c,  should  be  situated  in   the  same  plane  and  at  such  distances  as  to  make  the 

(159)  areas  of  the  sectors    sab,  she,    proportional  to  the  times.     Now  all  these  analytical  conditions 
are  completely  satisfied  by  supposing  the  planet,  at  the  times  of  the   three  observations,  to 

(160)  he  in  the  same  places  as  the  earth,  so  that  the  points  C,  C,  C"  may  coincide  with  A,  A\A", 

(161)  respectively,  in  fig.  92,  page  874  ;  in  this  case,  we  shall   have      C'B'  =  A'B'  =  6'.     This 
result  is  evidently  incompatible  with  the  physical  conditions  of  the  problem,  which  require 

(162)  that  the  light  in  coming  from  the   planet  to   the  earth,  should  proceed  from  points    a,  b,  c, 
fig.  84  ;  wiiich  are  at  some  distance  from  the  eye  of  the  observer  at     a',  b',  c',  respectively. 

(163)  In  most  cases  it  will  be  found,  that  where   there  are  three   positive   values  of    sin.  z,     we 
can  neglect  one  of  them   because   it  is   nearly  equal    to     à'     (161),   another   because    z 

(164)  exceeds    5'  ;    and  then  the  remaining  one  can  be  used.     If  it  should  however  happen  that 
the  equation  admits  of  two  solutions,  which  satisfy  the  proposed  conditions  of  the  problem, 

(165)  we  shall  thence  obtain  two  different  orbits.     In  this  case  the  true  orbit  is  to  be  determined, 
by  comparing  it  with  observations  taken  at  greater  intervals  of  time. 

As  soon  as  we  have  ascertained  the  value  of    z,     we  can  find     r',     from  the  equation, 
,      R'.sm.S' 


(167) 


(168) 


(iBC)     •-    sm.z  ^''^^-       ^°''    ""'^   ''""''    '"    (^^^^'        [rr']+[rV']  =  [r'r"].(P+l); 

substituting  this  in  the   first  member  of  (116),    and  dividing  by      P-j-1,     we   get,   by 
re-substituting     z' =  z  —  «5*     (30), 


[r'r"]   _        b  s\n.{z  —  5*) 

[fl^  ~  P  +  a  ■         simz 

Dividing  the  value  of  r'  (166),  by  the  preceding  expression,  we  get  (168).  The 
equation  (169)  is  easily  proved  to  be  correct,  by  the  substitution  of  the  value  of  P  (33)  ; 
these  expressions  are  the  same  as  (41"  41"')  ; 

[r  r"]      ^_  (P  +  a).R'.sin.^'  _ 
[i-'r"]  '^  ~     b.sm.{z  —  (5*)      ' 

(169)  [rr]  '  [r'r"]  •     '  p  ' 

(170)  We  shall  suppose  the  arcs  C'c,    C"c",  fig.  92,  page  S74,  to  be  let  fall  from  the  points 

(171)  C,  C"  respectively,  upon  the  great  circle  ABE'  ;  then  in  the  right  angled  spherical  triangle 

(172)  C'dE",  we  shall  have,  by  [1345^»]  and  (24,. 30), 


( 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  887 

[59991 
sm.C'c=sm.E'.sm.C'E'==sm.E''.sm.{C'B'+B'E")==sm.E''.s\n.{C'R+A'E''~A'B')    U") 

=sin.JE",sin.(2+^'£"— <S')  ;  (.74) 

in  like  manner,  in  the  right  angled  spherical  triangle   C"c"E',  we  have,  by  using  (31)  ; 

sin.  C"c"  =  sin.£'.sin.  C"£'  =  sin.E'.sin.i^".  {i75) 

Now  in  the  two  right  angled  spherical  triangles  C'c'C,    €"c"C,  we  have,  by  using  C  (22), 
the  fii'st  of  the  four  following   expressions  of    sin.  C'c',     sin.C'c";    from  these  we  deduce     (i^^) 
the  second  and  third  forms,  by   using  (29,  90)  ;  the   last  forms   are  the  same  as  those  in 
(174,  17Ô)  ; 

sin.C'c'=sin.C.sin.CC  =sin.C.sin.2/'=sin.C. ^^=s\n.E".sm.{z^d'E"—&)  ;  (n?) 

[rr"] 
sin. C  V=sin. C.sin.  CC  ^=sin. C.sin.2/ :=sin.  C.  — ~  :=sin.JG'.sin.^''.  (178) 

Dividing  the  two  last  of  the  expressions  (HS),  by  the  corresponding  ones  in  (177),  we 
eliminate  sin.C,  and,  by  a  slight  reduction,  obtain  the  value  of  r''.sin.^"  (181);  and 
this  value  is  for  brevity,  put  equal  to  p",  in  (49,  53).  In  like  manner,  by  supposing  (i?d) 
perpendiculars  Cc,,  C'c'^  to  be  let  fall  from  the  points  C,  C,  upon  the  great  circle  ./2"J5", 
so  as  to  form  the  right  angled  triangles  Cc,C",  C'c\C",  we  get  the  expression  of  ?•. sin.C 
(182)  ;  which  may  also  be  derived  from  (IS I),  by  changing  the  quantities,  relative  to  liie 
point  C,  into  those  of  the  point  C",  and  the  contrary.  This  value  of  r.sin.i^,  is,  for 
abridgment,  put  equal  to     p     in  (48,  52), 


CI80) 


(180') 


r 


\rr"^         sin.JS  '      .     ,      ,     ^  „ 
ir  r"l  sin   E 


In  the  last  place,  we  shall  suppose  the  arcs  Cc„,  C"c"„,  to  be  let  fall  perpendicularly  upon 
the  great  circle  A'B^  ;  though  we  have  not  actually  marked  these  arcs,  in  the  figure,  to 
avoid  confusion  ;  then,  from  the  right  angled  spherical  triangle  CE"c„,v,e  obtain  (184); 
and  from  the  triangle  C"Ec"^,  we  obtain  (185), 

sin.Gr„=:sin.jE".sin.C£"=sin.£".sin.(C£'4-^£'— ^£')=sin.£".sin.(C4-./4£"— ^£'); 
sin.C"c",=sin.£.sin.C"jG=sin.£.sin.(C"£'4-^"jG— ^"jB')=sin.£;.sin.(r+^"-B-^"£').    (,85, 

Now  by  proceeding,  as  in  (177, 178),  we  get,  in  the  right  angled  spherical  triangles    CC'i\_, 
C"C'c"„,     the  first  of  the  expressions  (187,  188)  ;  from   these  we  deduce  the   second  and     (,8^,, 
third  forms,  by  using  (29,  90)  ;  the  last  forms  are  the  same  as  in  (181,  182)  ; 


(183) 


(184) 


sin. Cc,=sin. C '.sin. CC'=sia. C'.s-in.2/"=sin. C.  tlj  =sm.E".sm.{^-\-^E"—AE')  ; 

rr 


(187) 


888  APPENDIX,  BY  THE  TRANSLATOR  ; 

[5999] 

(188)  sin.  C  "c",=sin.  C'.sin.  C'C"=.sin.  C'.sin.2/=sin.  C  ^Ç^=sm.E.s\n.{i"-\-A"E—JÎ"E'). 

Dividing  the  two   last   expressions  of  (187),  by  those  in  (188),  and  substituting  P  (38), 
we  get,  by  a  slight  reduction, 

(189)  r.sm.{^+JlE"—AE')  =  r".P.  ^^„  .  sm.{i"+A"E—A"E')  ; 

sin.ii> 

(190)  Substituting  CB=^—AE'-^5,  C" B"=?"—A"E'+Ô".{31,  24),  in  the  values  of  r,  ?•" 
(77),  we  get, 

(191)  r.sin.(^— ^E'+(5)=iî.sin.i5  ; 

(192)  r".sm.{C'—A"E'+&")=R".sm.5". 

Developing  the  first  member  of  (191),  by  [22]  Int.  ;  and  then  dividing  by   R.sm.6,    we  get 
(193)  ;  substituting,  in  this,  the  assumed  values  of    X,  x,     (46,  44,),  we  get  (194), 

.       cos.(AE'—S)  sm.(AE—S) 

(193)  r.sin.^. D-^—x~ r.cos.^.  - — ^—. — j —  =  1  ; 

it.sm.d  /t.sin.ô  ' 

] 

(194)  r.sin..*'.X — r.cos.f.— =1. 

x. 

Substituting  in  (194),  the  expression     r.sin.<'=p     (182),  and  then  multiplying  by     x,    we 

(195)  get,  by  using  the  symbol  q  (50);  r.cos.^=x.(Xp — l)=q  ;  as  in  (50,  52).  Again  if 
we  develop,  in  the  same  manner,  the  expression  (192),  and  divide  by  R".s\n.&",  we 
shall  obtain  (196)  ;  and  by  substituting  (47,  45),  we  get  (197)  ; 

,     cos.{j1"E'—ô")  s\n.{A"E'—5") 

(196)  r".sm.<".- 577-; — ^, —   — ?-".cos.f".  — 5^-1 — j;; — =  1  ; 

^     '  it".sin.ù"  il".sin.û" 

I 

(197)  r".sm.i".X"—r".cos.i".-i:^  1. 

Substituting     r''.sin.i"^=  p"     (181)  ;  then  multiplying  by     x.",     we  get, 

(198,  r".cos.i"  =  x".  (X"p  "  —  1)  =  q"     (51,53). 

Hence  it  appears,  that  we  may  deduce     r,  Ç,     fiom  the  expressions  of    p,  q,    as  in  (52)  ; 
and     r",  ?",     from     p",  q",     as  in  (53).     There  can   be  no   ambiguity  in  the   values  of 

(199)  ^j  ^")  because  r,  r",  must  necessarily  be  positive.  The  accuracy  of  the  calculation  can 
be  verified  by  substituting  these  values  in  (189),  to  ascertain  whether  this  equation  is 
satisfied,  by  the  results  we  have  obtained.  There  are  two  cases  in  which  other  methods 
are  to  be  followed.     In   the  first    place,  when  the  point   B  coincides  with  E',  or  with  its 

(200)  opposite  point,  in  the  spherical  surface  ;  or  in  other  words,  when  AE'—ô  is  C,  or  180"; 
because  then  the  equations  (182,  191)  are  identical;     x  (44)  becomes  infinite,  and, 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  889 

[5999] 

Xp  —  1  =  3-  =  0     (50)  ;  (201) 

so  that     q     (50)  is  indeterminate,     (n  this  case  we  must  find     r' ,  ^"     from  (53),  as  in  the  (202) 
former  method;    then     r,  Ç,     from   the  combination    of  (189),  with   (182  or    191);  by 

methods  similar  to  the  preceding,  and  which   require  no  particular  explanation.     We  may  (aoa) 

also  observe  that  when     AE  — 15     is  very  nearly  equal  to  0'',  or  180'',  the  same  method  (204) 
must  be  used,  because  the  former  is  deficient  in  accuracy  ;  adopting  that  combination  of 

(189)  with  (182),  or  with  (191),  which  will  give  the  best  form,  to  the  resulting  equation,  (sos) 
for  the  determination  of    r,  Ç. 


r^^"i    J. 


(206) 


The  second  case  which  requires  modification  is  where  the  point  B",  very  nearly  coincides 
with  E',oï  with  its  opposite  point;    in  this  case  the  determination  of    »•",  Ç",     by  the 
preceding  method  would   be  impossible   or  inaccurate,  on  account  of  the  smallness  of 
sin.(^"£'  —  Ù"),     in  the  value  of    x"     (45).     Then     r,  ^,     must  be  determined  by  the     (207) 
former  method  ;  but    r',^,     must  be  found  by  combining  (189)  with  (181),  or  with  (192),     isosj 
upon  similar  principles  to  those  adopted  in  the  preceding  case,  in  (205).     The  case  where     (aoo) 
the  points  B,  B  ,  coincide  with  E',  or  with  its  opposite  point,  is  excluded  in  (4). 

Having  found  the  arcs    4",  i"  ;   the  points  C,  C",  together  with  the  point  C",  will  be  given     (Sio) 
in  position  ;  and  the  arc  CC"  =  2f',  can  be  determined  by  means  of  the  given  arcs, 

Ç=CE';  ?"=^C"E',     (.31),  can) 

and  the  angle    CE'C'=E'  (28);  using  Napier's  formulas  [1345''®'''"],  to  find  the  angles 

C'CE'  ,CC'E',  and  [1345'*]  to  obtain  the  included  side  CC".     Moreover  in  the  triangle 

C'L'C",  we  have  the  angles   CEC\   C'CE,  and  the  side   CE,  to  find    C'C'  =  2f; 

also  in  the  triangle  C'E"C,  we  have  the  angles  C'E"C,  C'CE",  and  the  side  CE",  to  find 

CC  =2f".     These  values  of    2f,     2/",     are  however  much  more  easily  obtained  by  the    (2i3) 

[rV]     I  [rr']      1 

following  formulas  ;   observing  that  the  logarithms  of    , — — .  —,        r-— • .  -, ,      have  been 

obtained  by  a  previous  calculation  in  (168,169)  ; 


(912) 


(214) 


sin.2/"=  Hth  •  -T  •  sin.2/'.  'S'^) 

These  formulas  are  easily  proved  to  be  correct,  by  the  substitution  of  the  values  of,     [rr'],    aiti) 
[r'r"],  [rr"],     (90),  in  the  second  members,  and  making  a  slight  reduction.     Hence  we  have 
a  new  confirmation  of  the  previous  calculations  ;  because  we  ought  to  liave    2/+  2/""=2/';    (Si?) 
and  if  any  difference  be  found,  we  must  re-examine  the  calculations.     If  the  difference  be 
small,  we  may  apportion  it  between     2/,    2/",    so  that  their  log.  sines  may  be  equally    (si?') 
increased  or  diminished,  by  which  means  the  equation, 

VOL.  III.  223 


89Q  APPENDIX,  BY  THE  TRANSLATOR  ; 


[59991 


(319) 


(220) 


(225) 


(232) 


[rr']         r.sin.2/" 


will  be   satisfied.     If    /,/",     differ  but  little,  the  error  may  be  equally  divided  between 
2/    and     2f". 

Alter  we  have  obtained,  in  this  manner,  the  position  of  the  body  in  its  orbit, 
we  may  compute  the  elements  in  two  different  ways  ;  the  one  by  combining  the  first 
observation  with  the  second  ;  the  other  by  combining  the  second  observation  with  the  third  ; 
using  the  intervals  corresponding  to  the  times  of  observation  ;  by  the  method  given  in 
[5995  &ic.].     Before  these  operations  are  commenced,  we  must  correct  the  observed  times, 

(221)  for  the  effect  of  aberration,  by  subtracting  from  the  times  of  observations,  the  number  of 
seconds  represented  by,     «„  <„,  t^,     respectively,  and  computed  by  the  following  formulas, 

(222)  ^  =  493^p,;        t,  =  493>.p;;         t.^Am^^;'; 

observing  that  493  seconds  is  the  time  required  for  the  light  to  pass  from  the  sun  to  the 
^*^''      earth,  when  at  the  mean  distance,  which  is  taken  for  unity.     This,  expressed   in  parts  of  a 

(223)  day,  is  O"!"'  ,005706  [5998(114)],  whose  logarithm  is  7,75633.     The  values  of    p,,  p/,  p/'„ 
are  found,  as  in  (78,77,1 90),  to  be, 

_  R.sn^.{AE'—l)  _  ?-.sm.(^E'— 0 
'^^'  '''~sin.«-^£'+<5)  ~  sin.<5  ' 


R.sm.{à'—  z)  _  ?-'.sin.(^'— z) 
sin.2  sin.'J' 


„      ■R".sin.(^".E'-r)    _  r".sin.(^"£'— ^") 
'^^  ^'~~sin.(C"-^"£'-f-«5'')   "~  sin.*' 

If  the  situations  of  the  body,  at  the  times  of  the  three    observations,  be   nearly  known,  by 

(227)  any  previous  calculations,  we  may  immediately  correct  the  observations  for  the  effect  of 
aberration,  and    suppress   this  part   of  the  calculation.     Using   tliese  corrected  times  of 

(228)  observation     t,  t',  t",     and  the  value  of    k  (54),  we  shall  put,  as  in  [5994(319)]  ; 

(229,  r"^k.{t'—t);  r  =  k.(t"-t');  r'^k.{t"—t);  r'==r  +  r". 

When  we  have  gone   through  the  calculation,  as  far  as  to  find  the  value  of    y,     or      Y 

(23b)     [5995(129&;c.)],  which   expresses   the   ratio   of  the  area  of    the    elliptical   sector    sab 

[5995(164)],  to  that  of  the  corresponding  triangle  sab  ;  we  can  use  this  value  of    y  or    T, 

to  compute  more  correct  values  of    P,  Q,    by  the  formulas  (235,256)  ;  and  then  a  corrected 

''^''      value  of    z     from  (41,40',40).     This  part  of  the  calculation  is  to  be  repeated  till  the 

assumed  and  computed  values  of    P,  Q,     agree.     As  the  values  of    y     or     Y,     differ 

according  as  we  use  the  different  triangles  or  sectors,  sbc,  sac,  sab,  we  shall  denote  them  by 

y,  y',  y",     respectively  ;  so  that  we  shall  have  by  using  the  same  notation  as  in  (37  or  90)  ; 

(333)  sector  sbc  =  Jy.[/r"]  ;         sector  sac  =  |y'.[''''"l  ;         sector  sab  =  iy''.  [rr']  ; 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  891 

[5999] 
in  which  the  accents  have  the  same  symmetry  as  in  (82').     Now  by  Kepler's  first  law,  the 

sectors  sbc,  sab  [5994(47)],  are  proportional  to  the  intervals  of  time     t" —  t',  t' — t  or  t,  t" 
(229)  ;   hence  we  have, 


sector  sab  ^  "[^'^  W-  [t']  ^  y^'     p      ,gg.  , 
sector  sbc       t        hy.  [rV]      y 

consequently, 


(234) 


(«35) 
Correct 
value  of  P. 


and  as     y,    y"     are  very  .nearly  equal  to  unity  [5995(44,31  Sic.)],  we  shall  have     P  =  — ,     (236) 

for  a  very  near   approximation  to  the  value  of    P  ;     to  be  used   in  a  first  operation,  as  we 

shall  see  in  (259&ic.).     When  the  intervals   r",  r,    are  nearly  equal,  the  expressions  y,  y") 

will  commonly  not  differ  much  from  each  other,  and  then  the  assumed  value  of    P    (236),    (236) 

is  very  near  its  true  value.     We  shall   now  investigate  the  value  of     Q  ;     putting  it  under 

such  a  form  as  will  enable  us  to  assume,  at  the  commencement  of  the  operation,  a  quantity,     (23'') 

which  is  very  nearly  equal  to  it.     We  have  in  [5935(10)],  the  following  system  of  equations, 

in  which  the  anomalies  are  counted  from  the  perihelion,  (238; 

p  =  r.(l  4"  e.cos.v)  ;         p  =r'.[\  -\-  e.cos.y')  ;         p  =  r".(l  -|-  e.cos.t)'').  (239) 

Multiplying  these  three  equations,  by  the  values  of    ['V'],  —  [rr"],  [rr'\     (90),  respectively, 
and  adding  together  the  products,  we  get, 

p.  I  [/,•"]— [rr"]+[r/]  I  =  rrV".  I  sin.2/—  sin.2/'+sin.2/"  J  (240) 

-(-  rr'r".e.{sin.2y.cos.i)  —  sin. 2/'.  cos.u'-(-sin.2/".  cos.i)"}.  (2<" 

The  coefficient  of    e     (241  ),  vanishes  by  means  of  the  formula  (93)  ;  the  arbitrary  position 

of  the  point   M    being  taken  so  as  to  correspond  to  the  position  of  the  perihelion,  from  which     (242) 

the  angles     v,  v',  v",     are  counted  (938)  ;  hence  we  have, 

p,  I  [rV']—[rr"]  +  [?•/]  \  =  rr'r".  \  sin.2/—  sin.2/'+  sin.2/"  \ .  (243) 

Now  by  [31,  26]  Int.,  we  have,  by  observing  that    f'=f-\-f"     (29),  <2«) 

sin.2/=  2.sin./cos./;         sin.2/'— s  in.  2/'=  2.sin.(/"—/').cos.  (/"+/')  (245) 

=  —  2.sin./cos.  (/"+/').  (245') 

Adding  these  two  equations  together,  and  reducing,  by  means  of  [28]  Int.  and  (244),  we 
get  successively, 

siD.2/—sin.2/'+sin.2/-"=2.sin/.{cos./— cos.  (/'+/')! 

=  2.sin./.i2.sin.è.(/-f/'+/").sin.è.(/"+/'-/j=4.sin./.sin./.sin./".       ''*'' 


892  APPENDIX  BY  THE  TRANSLATOR  ; 

[5999] 

Substituting  this  in  (243),  and  dividing  by  the  coefficient  of    p,     we  get, 

4.r/?-".  sin j/". sin ._/''. sin._/" 
^''"  P  ^  [r'r"]  —  [rr"]  +  [rr']   " 

(248)  If  we  substitute  the  value  of     [rr']     (90)  in  [5995(60)],  we  shall  get     ^p  =^  '^^■',  using 

(249)  y",f",f—thc.,    for     y,/,  f  &tc.    as  in  (232 &c.),  also     t"    for    k.{t'—t),    as  m  (229). 
In    like   manner,   in    the   triangle    or  sector  corresponding  to  the  radii     r',  r",     we  have 

V  \r'r"\ 

(250)  \/P  =       — ■     The  product  of  the  two  expressions  of    y'p     (248, 250),  gives, 

y  y".  [>•»•']■[.'/'] 

(251)  p —  — ;;  -■ 

TT 

Putting  this  expression  of    p     equal  to  that  in  (247),  we  get, 

r  ,  „-,     r     ,n  ,  r    n      4rr".  nV.  sin/.sin./"'.  sin.f 

(252)  [r'r"]— [»T"]+[rr'J  =  „  .    n  r  '  'n  ■ 

Multiplying  the  numerator  and  denominator  of  this  expression  by    2rr'r".  cos.f.cos.f'.cos.f"  ; 
we  find  that  the  numerator  becomes, 

(253)  „"_  (2rr'.  sin./",  cos./") .  (2r'r".  sin./.cos/).(2rr".  sin/'.cos/)=rr".[rr']  .[»^r"].[rr '], 


(354) 


as  is  evident  from  (90),  observing  that  2rr'.sin./".cos./"=rr'.sin.2/'^[rr'],  &c.  Using 
this  reduced  value  of  the  numerator,  and  rejecting  the  factor  [rr'],  [rr"],  which  is  common  to 
the  numerator  and  denominator,  we  obtain  the  first  of  the  following  expressions:  the  second 
is  derived  from  the  assumed  value  of     Q     (39)  ; 


rr 


(255) 


.r".[rr"]  Q-hr"] 

[rV']— [rr"]+[rr']=^     „      ,„ ^        f fô  =  -^^hr*  • 

<-      J      L      J  1  L     J      2yy  .rrr  .cos.j.cos.J  .cos-J  2r^ 

Dividing  these  two  last  expressions,  by  the  coefficient  of     Q,    we  get, 

(256)  Q==tt". 


Correct  >r"  *  cos./cos./'.  COS./"  *  yy"  • 

valueof  Q. 


Now  the  angles  /  /',  /',    being  generally  small  ;  their  cosines  do  not  vary  much  from  unity  ; 


r 


,'2 


(257)  moreover  as  the  radius    r'    falls  between     r,  r",    we  shall  have      —77 ,       nearly     equal     to 

unity,    in    most   cases,    in    practice.       Hence    it  is   evident,    that   we    may    take,   at   the 

(258)  commencement  of  the  operation,  Q=tt",  for  a  very  near  approximation  to  the  value  of 
Q  ;  it  is  not  however  so  close  an  approximation  as  the  assumed  value  of  P  (236),  on 
account  of  the  magnitude  of  the  factor  cos./.cos./'.cos./".  The  success  of  Gauss's 
method  essentially  depends  on  this  happy  selection  of  the  unknown  quantities   P,  Q,  whose 

(258)  values  are  so  nearly  known  by  means  of  the  times  t,  f  ;  F  being  nearly  proportional  t<i 
the  ratio  of  their  times,  and     Q    proportional  to  their  products. 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET.  893 

[5999] 
We  shall  now  show  how,  by  means  of  the  approximate  values  of    P,  Q     (236,258),    Approii- 

mato   val- 

namely,  "os  «fp, 

t" 
-P=— ;  Q="";  (259; 

we  may  compute  the   elements  of  the  orbit.      The  preliminary  calculations  for  finding 
a,  b,  c,  d,  e,  5,  Ô',  Ô",  k,  k",  X,  X"      (32— 3G,  62,  63,  Sic,  44—47)  being  made  ;    we  may    (2co) 
substitute  in  (40)  the  assumed  value  of  P    (259),  and  we  shall  get  the  value  of    w  ;    then 
from  (41')  we  may  obtain  by  a  few  trials  the  value  of    ~  ;     substituting  this  in  (  166)  we  get    (acij 
/;    also, 

frr"!  [rr"] 

L;,]./.      (168),  LJ.,'.      (1G9);  (202) 

hence    we    deduce     p,  p"     (48,49);      q,  q"      (50,51);      Ç,  r      (52);      Ç",  r"     (53); 

then  we  obtain  the  arcs  /,/', /",    as  in  (211 — 215).    With  these  values  of  r,r',r",  f,f',f",    (203) 

we  may  compute  the  corresponding  values  of    ['■'■'],  [r'/'J,  [rr"]    (90)  ;  and  with  these  we 

can  obtain  new  values  of  -P,  Q    (38,39).     If  these  last  expressions  are  equal,  respectively,    (264) 

to  the  assumed  values  (259),  we  may  conclude  that  we  have  obtained  the  true  expressions 

of    r,i-',r'',  f,f'  ,f',  &,c.     But  if  the  assumed  and  computed   values  of    P,  Q,     differ    (205) 

from  each  other,  we  must  repeat  the  calculation,  in  the  same   manner  as  in    (260 — 265)  ; 

and  the  same  process  is  to  be  continued,  by  assuming  the  last  found    values  of    P,  Q,     for    (aoo) 

a  new  operation  ;  and  when  the  assumed  and  computed   values  of    P,  Q    agree,   they 

must    be    taken   for  the  correct    expression   of    P,  Q,     to  be    used   in   the   rest  of  the    (267) 

calculation,  in  finding  the  elements  of  the  orbit. 


(908) 


Taking  the  extreme  observations,  for  this  purpose,  we  have,  by  the  preceding  calculations 
the  values  of    r,  r",  2/"'=  v" —  v,    and  the  corrected  interval  of  time     t"—t.     With  these 
we  can  find,  by  the  precepts  in  [5995]  for  an  elliptical  orbit,  the  elements  corresponding  to 
the  plane  of  the  orbit  ;  namely,  the  semi-major  axis,  and  the  excentricity     e  ;     also,  the 
time  and  place  of  the  perihelion  in  its  orbit.     If  the  orbit  be  a  parabola  we  can  use  [5996],    (269) 
and  if  it  be  a  hyperbola  we  must  use   [5997].     The   place   of  the  node   and   inclination  of 
the  orbit,  to  the  ecliptic,  may  be  obtained,  by  means  of  the  triangle    nAC,  or    aA"C",    (270) 
figure  92,  page  874;  and  it  may  be  useful,  for  the   purpose  of  verification,  to  make  the 
calculation  hi  both  triangles  ;  and  take  the  mean  of  the  results,  if  there  should  be  any  slight 
difference.     In   the   triangle   nAC,    we  have   given,    the    angle    Q.CA^=^C,    the  angle    <?^^) 
a.AC=z\SO'^ — y,     and  the  included  side  ACz=AE' — ?,  to  find  the  sides  aA,  nC, 
by  Napier's  formulas  [1345^"'^^],  and  the  angle  Aa.C=cp,    by  [1345'*].     If  we  use  the    (272) 
triangle  V-.TC",  we  have  the  angles  ciC"A'=  6'",  n^"C"=  180"— 7",    and  the  side 
A"C"^A!'E'—l:";     to  find,  as  above,   the  sides   Q.A",nC",  and  the  angle  ^"i2C"=(p.    (273) 

VOL.  III.  224 


894 


APPENDIX,  BY  THE  TRANSLATOR; 


[5999] 


EXAMPLE. 

We  shall  take,  for  an  example  of  this  method  of  calculation,  the  following  observation3  of  the  planet  JunO, 
made  by  Dr.  Maskelyue  at  Greenwich.  The  times  of  observation  may  be  reduced  to  the  meridian  of  Paris,  by 
adding  the  difference  of  meridians,  which  Gauss  puts  equal  to    9"  20" ,9  =  o'^^'' ,00649 2. 


Data. 

(274) 

C275) 

(27G) 


(277) 
(278) 
(279) 


(S80) 
(281) 


(283) 
(284) 
(285) 


(286) 


Observation. 

I. 
II. 
III. 


Mean  time  at  Greenwich. 

October  5<i  lo'i  5i"' 06»  or  5'^''J',453.i52 
17  09  58  10  or  17  ,415393 
27   09    16    4i         or    27       ,386585 


App.  Right  Ascen- 
sion. 

357*  10"  22» ,35 
355  43  45  3o 
355    II    10  95 


App.  Declina- 
tion south. 

(i<i-  40'"  08s 

8   47    25 

10   02    28 


At  these  times  we  have,  from  the  solar  tables,  the  following  results. 


Observation. 

I. 
II. 
III. 


^'s  longitude  from  app. 
Equinox. 
192''  28"»  53» ,71 
2o4  20    21   54 

2l4     16     52     21 


Nutation  of 

equin.  point- 

+  I5^43 

-I-  i5  5i 

-f-i5  60 


©'s  distance 
from  Earth. 

0,9988839 
0,9953968 
0,9928340 


Q's  latitude. 

—  o'Ag 
+  0  79 

—  o  i5 


App.  Obliquity  of 
the  ecliptic. 

23"*  27»  59»,48 
23  27  59  26 
23  27    59  06 


With  these  data  we  obtain  the  apparent  longitudes  and  latitudes  of  Juno,  at  the  times  of  observation,  as  in  the 
following  table  ;  the  latitudes  being  south  are  marked  negative.  Also  the  longitudes  and  latitudes  of  the  zenith, 
which  are  equivalent  to  the  longitudes  and  complements  of  the  altitudes  of  the  nonagesimal  degree  of  the 
ecliptic  ;  the  latitude  of  the  place  of  observation  being  5i''28"'39'  ;  and  the  right  ascensions  of  the  meridian 
being  the  same  as  the  right  ascensions  of  Juno,  because  the  planet  was  observed  in  the  meridian.  This  method 
(283)     of  making  these  calculations  is  given  in  [5998(88,  89,  106,)]. 


Observation. 

App.  longitude  of 

App.     latitude     of 

Longitude  of 

Latitude  ot 

Juno. 

Juno. 

the  Zenith. 

the  Zenith. 

1. 

354*  A^"'  54^,^7 

—  4'' 59"' 3 1  «,59 

24''  29™ 

46''  53™ 

II. 

352  34    44   5i 

—  6   21     56  25 

23     25 

47   24 

III. 

35i   34    5i    57 

—  7    17     52  70 

23     01 

47   36 

The  parallax  of  Juno  being  unknown,  we  must  use  the  method  explained  in  [5998]  ;  by  applying  a  correction 
to  the  sun's  place,  as  in  [5998(121 — 126)],  where  we  have  computed  the  corrections  corresponding  to  the  first 
(287)     observation,  as  in  the  first  line  of  the  following  table  ;  in  which  we  have  given  the  con-ections  for  all  three  ot 
the  observations  ;  the  corrections  of  the  time  in  the  third  column  are  so  small  that  they  may  be  neglected. 


(289) 
(390) 

(291) 

(292) 
(293) 
(294) 
(295) 
(296) 


Observation. 


II. 
III. 


!  Reduction  "of  ©'s 
longitude. 

I  —  22',39 

!        — 27  21 
:  —35  82 


Reduction  of  ©'s 

distance. 
-|-  o,ooo3856 
-j-  0,0002329 
-\-  o,ooo2o85 


Reduction  of 
the  time. 

—  o»,i9 

—  012 

—  012 


These  longitudes  are  reduced  to  the  epoch  of  the  mean  vernal  equinox,  corresponding  to  the  beginning  of  the 
year  i8o5,  by  adding  the  corrections  for  the  precession  as  in  the  following  table  (3oi — 3i2).  We  must  also 
correct  the  longitudes  and  latitudes  for  the  aberration,  as  in  [5998(110,  iii)];  by  applying  to  the  planet's 
longitudes  and  latitudes  the  same  corrections  as  if  it  were  a  fixed  star  ;  these  quantities  being  also  contained  in 
the  same  table.  The  correction  for  the  aberration  of  the  sun  in  longitude  is  made  in  (277 — 279),  where  the 
tabular  numbers  have  been  increased     20^,25. 


(29Î) 

(298) 
(299) 


Observation. 

Reduction'of  precession 

Juno's  aberration 

Juno's   aberration 

to  January  i,  i8o5. 

in  longitude. 

in  latitude. 

I. 

n',87 

—  i9»,ii 

+  0^53 

II. 

10   23 

—  17  II 

+  I    18 

Ill 

8  86 

—  i4  .82 

+  1   75 

COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


895 


Wc  shall  now  apply  these  corrections  to  the  lono;itucles  and  latitudes,  in  order  to  obtain  the  values  of  A,  A',  A"  ; 
a,  a',  a"  ;  9,6',  8",  R,  R',  R"  ;  observing  that  the  signs  of  the  nutation  of  the  equinoctial  points  (277 — 279), 
are  such  as  are  used  in  finding  the  apparent  place  from  the  mean;  and  these  must  be  changed,  in  [3oi',  3o3'] 
in  finding  the  longitudes  from  the  mean  equinox. 

Observation  I.  Observation  II.  Observation  III. 

i2<'28"'53',7i  24''2o'«2i.,54  34''i6»"52',2i 

—  i5  43  —  i5  5i  —  i5  60 

—  22  39  — 27  21  — 35  82 
+  II  87  -)-  10  23  -I-   8  86 


Q's  longitudes    — 180'', 
Nutation  of  Equinoctial  points. 
Correction  for  parallax  of  Juuo, 
Precession  to  Jan.  i,  i8o5, 


Juno's  longitude, 
Nutation  of  the  equinoctial  points, 
Precession  to  Jan.  i,  i8o5. 
Aberration  as  a  fixed  star, 


Juno's  latitude, 
Aberration  as  a  fixed  star. 

Sun's  distance. 

Correction  for  Juno's  parallax. 

Corrected  distances    R,  R',  R", 

Logaaithms  of  these  distances, 
Mean  times  of  observation  at  Paris,  found  by 
adding  o'''''^',oo6492  to  the  times  at  Greenwich, 
From  (3o2,  3o4)  we  get. 


.^=I2''28"'27S,76 


354''44"'54',27 

—  i5  43 
4-  II  87 

—  19  II 


a=354''44'"3i',6o 


—  4''59'"3i«,5g 
+  53 


ô=— 4''59"'3i',o6 


0,9988839 
-(-  o,ooo3856 


R  =  0,9992695 


log.  i?  =  9,9996826 


(=Oct.  5"''>'',458644 

^— a=i7''43'n56',i6 
A' — A=ii  5i    21   29 


.4'=24''i9"'49'>o5 


352''34'"44»,5i 
_  i5  5i 
+  10  23 
—  17  II 


().'=352''34"'22',I2 


—  6''2i™56»,25 
+  I    18 


-6<'2i'"55",07 


0,9953968 
-(-  0,0002329 


iî'  =  0,9966297 
log.  R'  =  9,9980979 


i'  =  Oct.  i7''"5",42,885 


.<?'— a'=3i''45"'26",93 
A"—A'=  9  56  20  60 


.;«"=34''i6'"09»,65 

35i<'34"'5i',57 

—  i5  60 
+   8  86 

—  i4  82 


(,_"=35!''34'"3os,oi 

—  7<'ly'»52»,70 
+  1     75 

6"=  —  jii  7™5o»,95 

0,9928340 
4-  o.ooo2o85 


R"  =  0,9930425 


log.  i{"=  9,9969678 

<"=Oct.  27''^>',393o77 

.4"— a"=43<'4i"'39»,64 
A'i—A=7i  47  4 1  89 


[5999] 

(300) 

Dau. 

(301) 
(301') 


(302) 
(303) 
(303') 


(304) 
(305) 

(306) 
(307) 

(308) 
(309) 

(310; 

(3U) 
(312) 


As  all  the  latitudes  have  the  same  sign,  we  have  considered  them  as  positive,  in  the  following  calculations 
(3i2'— 319,  &c.),  and  have  drawn  the  figure  94,  page  8g4,  to  conform  to  this  supposition,  making  the  points 
B,  B',  B",  C,  C,  C",  Stc.,  fall  below  AA",  instead  ol  above,  as  in  figure  92,  page  874.  The  change  of  the 
directions  in  the  lines  AB,  A'B',  A''B",  of  the  figure,  are  indicated  by  the  signs.  Thus  if  we  had  supposed 
a  to  be  negative,  in  finding  y  (3i4),  we  should  have  tang.â  and  tang.j,  ricgadVe;  but  this  negative 
value  of  y  merely  indicates  that  the  arc  AB  falls  below  AA",  as  in  figure  94,  instead  of  above,  as  in  figure  92, 
page  874.  Hence  we  see  that  by  a  careful  attention  to  the  actual  situations  of  the  points  of  the  figure,  we 
may  avoid,  in  a  great  degree,  the  trouble  of  noticing  the  signs  in  these  preliminary  calculations;  and  by  referring 
to  the  figure,  are  less  liable  to  mistakes,  than  we  should  be,  if  we  restricted  ourselves  exclusively  to  the  analytical 
method  of  computation. 


To  find     y,  yi,  y".     (62). 

6     (3o6)                             tang.  8,9412495 

A  —  a    (.3ii)                      subtract  sin.  9,4836865 

y  =  i6<'bo'"o8',38              tang.  9,4575630 


6'     (3o6)  tang.     9,0474879 

.1'  —  a'     (3ii)  subtract   sin.     9,7212540 

>.'  =  ii<'58"'oo»,33  tang.     9,3263339 


6"     (3o6)  tang.    9,1074080 

A"  —  a.'i    (3ii)  subtract  sin.    9,83 12855 


>"  =  io''4i'"4o',;7 


tang.    9,2761225 


To  find    <f,  ef',  J".     (63). 
A  —  ()_     (3ii)  tang.    9,5048260 

y     (3i4)  subtract    cos.    9,9828366 

<f=jîB  =  i8<'23™59',2o 


A'  — a.'     (3ii) 
y     (3 16) 

<f  '  =  A'B'  =  32"*i9m24',93 


.4"  — a"     (3n)  tang.     9,9650091 

y"    (3i9)  subtract    cos.    9,9923903 

J"  =  .î"£"  =  43''ii'"42>5  tang.    9,9736188 


(312') 


(312') 


Preiimin- 
iiry  calcu- 
lations. 

(319'") 
(313) 


tang.  9,5219894  (314) 

tang.  9,7916902  (314') 

subtract    cos.  9,9904579  ,3,5, 

tang.  9,8012323  (316) 


(317) 
(318) 
(319) 


896 

[5999] 


APPENDIX,  BY  THE  TRANSLATOR  ; 


To  find  E,  A'E,  A"E,  in  the  triangle  EA'A". 


(320)  £jj/^//— i8o<i— 5,'=i68<'oi'»59',67    (3i6).  Using  Napier's  Rules  [i345' 

(321)  E£l'J}'=  y"=   10  4i   4o   17     (3l9) 
(323)  ■ 


'■]• 


(323) 

Prelimiu- 

ary  calcu- 
lations. 


(324) 


(325) 

l326) 


(329) 


(330) 
(330') 
(331) 


Sum=2Si=i78  43  39  84  ;      S,  =89''2i">49',92 
Difference=2Z)i  =i57  20  19  5o  ;     Dj  =78  4o  og  75 


Z)i  sin.    9,9914519 

,S'j  aiith.  CO.  siQ.     0,0000268 

4(4"—^')=  4'*58'"io',3o         tang.    8,g3g2834 


t{A"E—A'E)=  4  52  24  38 

li(AiiE+AiE)=56  58  5o  78 

Difference  is  J1'E=^2  06  26  4o 
Sumis  j2"£=6i  5i  i5  16 


tang.    8,9307621 


i)j                                                                COS. 

Si                               arith.  co.  cos. 
i(^"— ^')     (3 1 2)                                      tang. 

9,2932968 
1,9545834 
8,9392834 

à(^"-E+^'£)=56''58'"50S78                 tang. 
A«—Âi     (3 1 2)                                            sin. 

0,1871636 

9,2370422 

S'E    (325)                                 aiith.  co.  sin. 
y     (3i9)                                                    sin. 

0,1028335 
9,2685128 

£=2i«i9'"34»,oo                    sin. 

8,6o83885 

To  find  El,  AE',  A"E',  in  the  triangle  E'AA'K 

(327)  J5;/^^//=i8o— >^=i63''59™5i«,62    (3i4) 

(328)  E'A"A=y"=  10  4i  40  17    (3i9) 


Sum  ^2S;  =174  4i  3i  79; 
Diffei'ence^2Z)o:=i53  18  11  45  ; 


Sj  ==87''2om45',9o 
Dj  =76  3g  o5  73 


JD,  sin.    9,9881058 

S»  arith.  co.  sin.     o,ooo466o 

J(.4"— ^)=io''53'"5o»,95  tang.     9,a844852 


4(jî"£' — «£')=io  37  1 5  55 
i.(^"£'+^-E')=43  49  45  33 

Difference  is  AE'=33  12  29  78 
Sum  is  A"E'=54  27  00  88 


tang.    9,2730570 


-D2  COS.  9,3633710 

S'a                                   arith.  co.  cos.  1,3343907 

i{A"~A)    (3i2)  tang.  9,2844852 

^{A"E'+AE')=43''49'"4S^,33  tang.  9,9822469 

A'' — 2     (3i2)  sin.  9,5697089 

AE'     (33o)                                   arith.  co.  sin.  0,2614699 

y"    (326)  sin.  9,2685128 

E'—  7'*x3"'37',70  sin.  9,0996916 


To  find  E",  AE",  A'E",  in  the  triangle  E''AA'. 

(»2)     £"^^'=180"— }.=i63''59"'5is,62    (3i4) 


t333) 


(334) 


1335) 
(336) 


E"A'A=y'=  II  58  00  33     (3i6) 

S3  =87''58"'55«,97 
D3  =76  00  55  64 


Sum  2^3=175  57  5i   95  ; 
Difference  21)3^15201  5i   29; 


n^  sin.    9,9869333 

S,  arith.  co.  sin.     0,0002694 

4(jî'— jî)=  5''55"'4o%64  tang.    9,oi63358 


ll{A'E"—AE")=  5  45  25   19 
i(A'E"+AE")=^35  28  32  49 

Difference  is  AE"^2g  43  07  3o 
Sum  is  A'E"=4i  1 3  57  68 


tang.    9,oo35385 


-O3 

(3l2) 

è(^'£"+^-E'')=35''28'»32',49 

A'— A    (3 1 2) 
AE"      (335) 
y'    (3i6) 

£"=  4'^55'"46',22 


cos.  9,3832o5i 

arith.  CO,  COS.  1,4533373 

tang.  9,oi63358 

tang.  9,8528782 

sin.  9,3127087 

arith  co.  sin.  0,3047442 

sin.  9,3166918 

sin.  8,934144? 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


897 


To  find  the  angles  B,  B",  in  the  triangle  EiBB",by  [i345*''"]. 

.îE'=33<'i2'»29<,78    (33o)  jî"£'=54''27moo»,88     (33o')  BjB'B"=jE'=7''i3'"37',70    (33i) 

^B=i8  23  59  20    (3i4)         A'iB"==4^  11  42  o5    (Sig) 


[5999] 


E'B=iA  48  3o  58=^£'— < 
E'B''=ii  i5  18  83     (339) 


EiBii=ii  1 5  18  83=^"JS'— cf"; 


Sum  2S'4  =26  o3  49  4i  ;  «4  =i3''oi"'54»,7i 

Uiff.iiD,  =  3  33  II  75  ;  Z)^  =  i  46  35  88 

J)^  sin.    8,49i4o56 

S^  arith.  co.  sin.     0,6468671 

^BE'Bii=  3<56'"48»,85  (337)cotan.     1,1996098 


è(B"— JS)=  65  19  46  66 

k{B"+B)=  86  28  3g  26 

Sum  is  B"=i5i  48  25  92 
Diff.  is  B=^  21  08  52  60 


tang.    0,3378825 


(337) 
(338) 


(340) 

Pcelimin- 
«ry  calcu- 
latione. 


£=2i<io8'"52',6o    (343) 
E"=  4  55  46  22    (336) 

Sum  2  «5  =2604  38  82 
Diff  2i>5=i6  i3  06  38 


^5  =l3''o2mi9',4l 
Us  =  8  06  33   19 


D^  sin.    9,i494o55 

S5  arith.  co.  sin.    0,6466425 

4BE"=5<'39'»34«,o5   (345')    tang.     8,996067g 


i(E''B"— £'B*)=3  32  43  98 
à(E"B'4-B'S*)=5  45  01  93 


tang.    8,7921 1 5g 


-D4 

«4                                           arith. 
iBE'B"     (337) 

COS. 
CO.   CO.S. 

cotang. 

9.99979'  2 
o,oii33ig 
1,1996098 

(341) 

i(B"-)-.B)=86<i28m39.,26 

tang. 

1,210732g 

(342) 

(343) 

riangle  Ei'BB',  by  [i345so>*']. 

^£"=29<'43'"o7»,3o    (335) 
^B=i8  23  5g  20     (3i4) 

(344) 
(345) 

BE"=ii  ig  08  10 

(3450 

S, 
hBE'     (345') 

è(£;".B*-fB'B*)=5''45'«oi',93 


COS.  9,9g56356 

arith.  co.  cos.  o,oii343g 

tang.  8,gg6o679 

tang.  9,oo3o474 


To  find  i  », 
.î'£"=(336)  4i''i3"=57»,6 


AE'—S,      AEi'—f,      .l'E—J-'+f*,     AiEi'—J'-Jri*,ii.c. 


J-'— <f"=^î'B*=3i  56  II  77 
<r'=.4'B'=(3i6)  32  19  24  93 

i*=B'B*=z  o  23  i3   16 


.î£'(33o)=33''i2"'29',78 
J-    (3i4)=i8  23  5g  20 

AE'-i=i4  48  3o  58 


AE'—i  sin.  g,4o75423 
COS.  9,9853302 


^£"(335)=29''43'»07',3o 
<r  (3i4)=i8  23  5g  20 


AEi'—f=\i  19  08  10 


AE'i—i      sin.  g,2928537 


.4'£(325)=52<'o6m26',4o 
.r'-J*(349)=3i  56  II  77 

A'E-i  '-fr=2o  10  14  63 

■t'E—i  '-I-J  »  sin.  g,5375gog 


(346) 


Sum  E''B*=Q  17  45  gi.  The  sum  is  talsen  because  £"B*  is  opposite  to  the  greatest  of  the  two  angles  S  E"      :3-iî) 


(348) 
(349) 

(350) 
(351) 
(351') 


j}'E(325)=52<'o6">26',4o  A<E"  (336)=4i''i3"'57«,68 
J'(3i6)=32  19  24  g3J     i<  (3i6)=32  ig  24  g 


AiE—î'=\g  47  01  47 


AiEii—t'=  S  54  32  75 


^'E"(336)=4i''i3"'57',68 
J~'— #"(34g)=3i  56  II  77 


WEii—S'+i*=  9  17  45  gi 


A'S'i—i-JTS'   sin.  9,2082704 


./Î"£(326)=6i<'5i'«i5',i6 
<f"(3i9)=43  II  42  o5 


^"-B— <r"=i8  39  33  II 


A"E—ii'    sin.  9,5o5o663 


!l''E'  (33o')=54''27'"oo',88  (s.yj) 
<f"  (3i9)=43  IT  42  o5,353) 

A'iE'—i''==i\   i5  18  83(354) 


A"E'—i  "    sin.  9,2904350  (355) 
COS.  9.ggi566[  (356) 


To   find  iî.sin.J 

R    (3o9)    log.    9,9996826 

f     (3i4)    sin.    9,499'994 

iJ.sin.J~        log.    9,4988820 


J?'.sin.<f' 


iî".sin  J~". 


R'     (3o9)     log.     g,g98o97g 
f'     (3i6)     sin.    9,7281105 


iî'.sin.if'      log.    9,7262084 


R"      (309)      log.      9,9969678  ,357) 

J""    (3ig)     sin.     9,835363i  (358) 

i}'',sin.<f'"     log.     9,83233o9  (gjm 


VOL.  111. 


225 


898 

APPENDIX, 

BY  THE  TRANSLATOR 

) 

[5999] 

To  find    a,  b,  c,  d,  e.    (32—36). 

(3ti0) 
(3G1) 

(302) 

(3C3) 

A"E' 
AE<- 
iî.sin 
fl"sin 

.y 

'    (355) 

(35i)                            arith. 
(359) 
(359)                         !"■'*• 

sin. 
CO.  sin. 

log. 
CO.  log. 

9,2904350 
0,5924577 
9,4988820 
0,1676691 

Ai'E—S"    (355) 
A'E-S'+S-*    (35i) 
W.smJ-i    (359) 
Rii.sin.e-"     (359) 

sin. 
arith.  co.  sin. 

log. 
arith.  co.  log. 

9,5o5o663 
0,4624091 
9,7262084 
0,1676691 

(364) 

3=0,3543593     (32) 
2 

log- 
log. 

9,5494438 

6     (33)              log. 
J-*     (35 1  )                         secant 

9,8613529 

(365) 

o,3oio3oo 

0,0000099 

(366) 
(367) 

3.1og.(iJ'.sia.J'')     (359) 
i*    (35i) 

c-i     (34) 

c 

sin. 

log- 
log. 

9,1786252 
7,8295726 

ft.sec.cf  "=0,72671 28 
1^0,3543593 

ft.secf*— 3^0,3723535 
J.sec.J* — 1=  —0,2732872 

d=— 1,3624994 

log. 

(364) 

log- 
log,  subtract 

(35)         log. 

9,8613628 

(368) 
(369) 

7,3092278 
2,6907722 

9,5709555 
9,4366i92„ 

(370) 

o,i343363„ 

(371) 
(372) 

J«     (35i) 
t.sec  J  »— 1     (369) 

tang, 
log.  subtract 

7,8295825 
9,4366 1 92„ 

(373) 

e    (36)             log. 

8,3929633n 

(374) 

/{.sin.tT    (359) 

(375) 

AEi—S    (36i) 

(376) 

■X=L\ 

,2340696 

(377) 

JlE'—f    (35i') 

(378) 

R.s\n.t    (359) 

! 

(379) 


To  find    K,  «.",  X,  k".    (44—47)- 

R'l.sin.J-"     (359) 
M'lE'—J-"     (355) 


log.     9,4988820 
arith.  co.  sin.     0,5924577 


log.    0,0913397 


cos.     9,9853302 
arith.co.log.     o,5oiii8o 


(46) 


log.  o,, 


log.  9,83233o9 
arith.  co.  sin.  0,7095650 


»"=3,4825384  (45)       log-  0,5418959 

Mi'E'—f"    (356)  COS.  9,991 566i 

Ri'.sin.S^"     (359)  arith.  co.  log.  0,1676691 

\"     (47)  log-  0,1592352 


First 
approiT- 
ointion. 

To  find  the  j 

(380) 

«'— f=ii,96324i     (3io) 
k    (54) 

(381) 

t"      (229) 

T      (38 1)                          su 

(382) 

i'=— =      1,1997804     (259) 

T 

a=     0,3543593    (364) 
(i  =  — 1,3624994    (370) 

(383) 
(384) 
(385) 
(386) 

(387) 


First  Apphoximation  to    P,  Q. 
To  find  the  first  values  ofP,  Q,    w,  Q'  and  the  equation  in  z.     (4i')- 


log.  1 ,0778489 

log.  8,23558:4 

log.  9,3i343o3 

subtract  log.  9,2343285 

log.  0,0791018 


P-|-a=   1,5541397 
P+d^ — 0,1627190 

e    (373) 

w=I3*I6"'54^77  (4o) 
J-»=   23  i3  16  (35i) 


log.  0,1914901 

log.  CO.  0,788561 8n 

log.  8,3929633n 

tang.  9,373oi52 


("— ('=9,971192  (3 10) 
k     (54) 


log.  0,9987471 
log.  8,23558i4 


T       (229) 

t"  (38i) 


c    (369) 
w  (386) 


log.  9,2343285 

log.  9,3i343o3 

Q  =  tt"  (259)  log.  8,5477588 

log.  2,6907722 

sin.  9,36i24o4 


Q'    (4o') 


log.  0,5997714 


Hence  the  equation  (4i')  becomes, 

o,59977i44-4.1og.sin2;— log.sin.(2;— i3''4o"'o7'',93)=o. 


w+if*  =i3  4o  07  93 

To  find  z  by  approximation  from  the  preceding  equation,  (386.) 
By  a  slight  inspection  of  the  table  of  log.  sines,  we  find  that  «  =  i4''  may  be  assumed  for  a  first  process, 
in  the  following  table  ;  and  î=  i5''  for  a  second  process.  The  errors  of  these  assumed  values  leads  to  a  third 
value  i4''45"',  and  so  on,  by  repeated  operations  as  in  the  following  table,  till  we  get  the  correct  value  of  z. 
In  the  same  way  we  may  find  the  other  values  of  z,  which  satisfy  this  equation;  as  in  the  second  example  of 
the  table. 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


899 

[599U] 


Assumed  value  ot    z, 
Its  lo;:;.  sine. 

1 4-' 
9.384 

9,4 1 3 

i4''45™ 
9,406 

7,624 
0,600 

i4'^3o"' 
9,3986 

9,4oi52 

i4''35'" 
9,4oio3 

i4''35'"09> 
9,401  II 

32<i2m 
9,72461 

32"3"' 
9.72481 

32''2'"26'' 
9,72470 

Muhipliod  by  4, 
A.M  lo^.Q', 

7,536 
o,6oo 

7,652 
0,600 

7,5944 
0,5997 

8.1941 
8,i6i5 

7,60608 
0,59977 
8,2o585 
8,21086 

7,6o4i2 
0,59977 
8,2o38g 

8,203o2 

7,60444 
0,59977 

8,89844 
0,59977 

8,89924 
0,59977 

8,89880 
0,59977 
9,49857 

9,49856 
0,00001 

v;  — i3''4o"'  7',g3)leg  sine, 
Uifiereiice, 

8,i36 

7,762 

8.252 

8,366 

8,224 
8,276 

8,20421 
8,20421 

9,49821 

9,49839 

—  0,00018 

9,49901 
9-49877 

4-0,3^4 

—0,1 14 

— o,o52 

-|-o,o336 

— o,oo5oi 

-{-0,00087 

0,00000 

-|-0,O0024 

(.TSS) 


Hence    we    find    tliat  the    value   of     z,     corresponding   to   this    equation   is    z  =i4'^35'"09S;  the  other  value 
z  =32''2'"26»    is  nearly  equal  to    J" '=32''r9"'24',93     (3i6),  and  is  to  be  neglected,  as  in  (i57,  &c.) 


To  find    r<    (jj),  and  the  factors    (4i",  4i"')- 


iî'.sin.if'   (359)  log.    9,7262084 

z=i4''35"'09»       (390)  sub.  sin.    9,4011076 

log.    o,325ioo8 


r>     (77) 
.f  •  (35i) 
z—i*     =i4''ii'"55',84 


23""  1 3',  1 6 


.4'£-J'(354)=i9''47"oi',47 
z=i4  35  09  00 


z-f-^'£-J''=34  22  10  4: 


Its  log.  sine  =9,7516861 


j'£'/_j>'(354)=8''54"'32',75 
(390)    z^i4  35  09  00 

z-|-jî'£"— <f '=23  29  4i  75 


Its  log.  sin.  =9,60061 13 


I  Ir'r"]  "     S 


iî'.sin.,r'     (359) 
P+a     (383) 


log.    9,7262084 
log.    0,1914901 


b    (364)  log.  CO.  0,1 38647 1 

z— if*  (394)  arith.  co.  sin.  o,6io324o 

(4i")  log.  0,6666696 

P     (382)  subtract  log.  0,0791018 

(4i"')  log.  0,5875678 


(.TOO) 


First 

Approxi- 

matluii. 


(;»1) 
1 392) 

(394) 
(395) 

(39(5) 

(397) 
(398) 


To  find  p,  (p"),  (48,49)  ;       q,  q"  (5o,  5i)  ;        ^,  ^n,  r,  r"  (52,  53). 


(394) 


I  :r'T"]    s 

z-\-^'E—i'  (398) 

E        (326) 

E'        (33i) 

P     (48) 
'^     (379) 

X.  =  1,2340696      (376) 

X  px  =3,1977206 
q  =  xpjt  —  X  =  1 ,96365io    (5o) 
P    (4o3) 

—  =  tang.f  (52);    f=23'^i7"'33',38 

e'=  CE'  (409) 
q  (407) 

r        (52) 


log.  0,6666696 

sin.  9,75i686i 

sin.  8,6o83885 

arith.  co.  sin.  0,9003084 


log.  9,9270526 
log.  0,4864482 
log.     0,0913397 


o,5o484o5 


log.     0,2930643 
log.     9,9270526 


■"I 


(396) 


['■'■']■ 

z-^^iE"-J-'       (398) 
E"        (336) 
E'         (33 1) 


log.     0,5875678       <399) 


sin. 

sin. 

arith.  co.  sin. 


9,6006113 
8,9341447 
o,9oo3o84 


P"  (49)  log. 

(379)  log. 

x"=  3,4825384  (376)  log. 

>"p"»"=  5,2937488      log.  0,7237633 


0,0226322 
0,1592352 
0,5418959 


tang.  9,633g883 


sec.  0,0369220 
log.  0,2930643 


log.  0,3299863 


--k"p"k"  —  H."  =  1,8112104    (5i)  log. 
(4o3)  log. 


0,2579689 
0,0226322 


T,  =  tang.,>-"(53)  ;    ^"  =  3o'*i  i'"o4',25  tang.  9,7646633 


?"=C"E'     (409) 

q"   (407) 

r"     (53) 


sec. 
log. 


0,0632798 
0,2579689 


(400) 

(401) 

(403) 

(403) 

(404) 

(405) 

(406) 

(407) 
(408, 

(409) 

(410) 
(411) 


log.      0,3212487       (412) 


900 

[5999] 

First 
Approxi- 
mation. 
(413) 

(413') 


APPENDIX,  BY  THE  TRANSLATOR  ; 


Tofijld  the  arc    CC"  =  2f',    in  the  triangle  CE'C",  by  [i345'"''"]. 


Ç=CE'  =  53<'i7'n33»,38     (409) 

}ii=aiEi        =  3o  n   o4  25     (409) 

Sum  2S6  =  53  28   37  63  ; 
Diff.  2D^  =    6  53   3o  87  ; 


Ss  =26'*44"'i8',82 
J5e  =  3  26  45  M 


(414) 


(415) 
1416) 

(417) 


-De 

hE' 


sin.    8,7789252 

arith.  co.  sin.    0,3468646 

3''36"'48«,85  (34i)     cotan.     1,1996098 


è(C'— 0")=  64  4i  56  92 

è(C-f  C")=  86  45  58  08 

SuraisE'CC"=i5i  27  55  00 

Diflf.is£'C"C=  2204  01    16 


tang.    0,3253996 


Se 

à-B'     (340 

COS. 

arith.  co.  cos. 
cotan. 

9,9992141 
0,0491  i5i 
1,1996098 

è  (C-{-C")  =86''45"'58',o8 

tang. 

1,2479390 

£'C"C  (4 16) 
CE'     (4 1 3) 
E'        (33i) 

arith.  co.  sin. 
sin. 
sin. 

0,4261700 
9,5970663 
9,0996916 

2f=CC"  =  7''36"'32'.42 


sin.     9,1219279 


(418) 
(419) 
(420) 


To  find  the  arcs  CC'=7f"  ,    C'C"=2f,    (214,  2i5). 


r  (4i2)                                log.  0,3399863 

5  ILLJ  .r'  (    (394)            arith.  co.  log.  9,33333o4 

jf'=ca'     {All)                                «'°-  9>i"9'79 

2/=C'C"         =3''29'"47',5o               sin.  8,7862446 
2f'=CC'        =4  06  44  95    (4i9) 


(421)     Sumis2/'=CC"   =7  36  32  45 

Computed    CC"=7  36  32  42     (4i7) 


r"  (4 12)  log.  0,3212487 

< -7 — Pi  •'■' (     (396)  arilh.co.log.  9,4124322 

2/         (417)  sin.  9,1219279 

3/i'=CC'=4''o6'n44',95  sin.  8,8556o88 


(423) 
(4231 
(424) 

(425) 

(42G) 
(427) 
(428) 


To  find    f, ,  f/,  f,"  ■    in 

To  find  fi  and  f,  (224). 
.4£'=33<ii2"'29»,78  (33o) 
,>-=23  17  33  38  (409) 

AE'—^=  9  54  56  40     sin.  9,236o3 


r  (4i2) 
i  (358) 

f/       (224) 


log.  0,32999 
arith.  co.  sin.  o, 60080 


order  to  correct    t,  V,   t",    t,  t",  for  the  aberration,  (223) 

To  find  f/  andt„  (226). 
■T'  =32<'i9m24',93  (3 1 6) 
z    =i4  35  09        (390) 

sin.  9,48382 

log.  o,325io 


<r'— 2=17  44  i5  93 


log.  0,06682 
Constant  log.  of  aberration      7,76633 


Correction  £î=o,oo6665  log.  7,82316 
Observ.    Oct.  5,458644    (3io) 


(429)      Corrected  Oct.  5,461989=^. 

(4301 
(431) 


r'  (392) 

J-'  (358)  arith.  co.  .sin.  0,271? 

(223)     Constant 


log.  0, 

log.  7,75633 


To  find  f/'  and  t^  (226). 

^"£'=54''27»oo',88  (33o') 

^"=3o  II  o4  26  (409) 

^"£'—^"=74  1 5  66  63  sin.9,6i38i 
r"    (412)  log.  0,32125 

j"    (358)        arith.  co.  sin.  0,16464 

log.  0,09970 
log.  7,76633 


(223)  «2  =  0,006873        log.  7,837i4 

Oct.     17,421885    (3io) 

Oct.     i7,4i5oi2=(',  corrected. 
Oct.       5,45ig89^i,    corrected. 


Int.  r—<=t  1,963023    log.   1,0778409 
Constant  ft   (64)  log.  8,23568i4 


Corrected  t"     (229)     log.  9,3i34223 


f,"     (226) 
Constant 


(3=  0,007178      log.  7,856o3 
Oct.      27,393077    (3io) 

Oct.      27,385899=(",  corrected. 
Oct.      i7,4t5oi2=:<',  corrected. 


Int.  t"—t'=  9,970887  log.  0,9987338 
Constant  ft    (54)      log.  8,23558i4 


Corrected  t     (22g)     log.    g,2343i52 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


To  find    y"    from    r,r',  ij"s  V—t.    Li'A-e  [5995(187)]. 


r'    (39.) 
r    (4i2) 


log.     o,325ioo8 
log.     0,3399863 


(■' 


=t,Ulg4.(j5'Ll-!t')  log.      9,9951145 

r 

45*fio=44''55"'o9'.957  tang.  9,9987786 
u;= —    4"5o»,o43 

iw= —    9'"4o',o86 


(39.) 

(412) 


o,325ioo8 
0,3599863 


sum  0,6550871 
half  0.3275436 


(it')*  log.  0,9826307 
arith.  co.  9,0173693 


tang.  7,44907,, 

same  7,44907,1 

y":=2<io3'"22',475     (420)    sec.  0,00028 

tang2.2t/j.sec/""=o,ooooo79i         log.  4,89842 


constant  log.  5,5680729 

V — t        11,963023     (43o)  log.  1,0778409 

same  i  ,0778409 

3Xlog.sec./"     (439)  0,0008391 

^.log.  {rr')  arith.  co.  (433)  9,0173693 


log.     6,7419631 


/"^2''o3"'22*,475     (435)     sec.    0,0002797 

4/"=i  01  4i    2375  sine    8,2538985 

same    8,2538g85 


?in2.4/".sec/"=o,ooo322i6  log.    6,5060767 

tang2.2i/;.sec/"=o,ooooo7gi     (436) 


/=o,ooo33oo7 
1=0,83333333 


i-|- 1=0,83366340    subtract  log.    9,9209908 
mm     (438)  log.    6,7419631 

A  =  0,0006621 7  log.     6,8209723 


Corresponds  in  Table  VIII,  toapp.  log.  y"y"=o,ooo6383 

log.  y"^o,ooo3i92 

To  find    P. 

arith  co.  log.  9,9996808 

log.  0,0002285 

log.  9,3i34223 

arith.  co.  log.  0,7656848 


y" 

(447) 

y 

(447) 

t" 

(43i) 

T 

(43i) 

Corrected  P=  ?^    (235) 

y'V 

Assumed  value  of  P   (382) 


log.    0,0790164 

log.     0,0791018 

Difference   — o,oooo854 


JCa 


We  may  remark  that  the  value  of  ft  (445)  does 
not  require,  in  this  example,  any  correction  for  the 
quantity     |     [5995(14-)],  which  is  wholly  insensible. 


To  find    y    from    r',r",    5/,  ("—('. 
r"    (4i2)    log.  0,3212487(412)   .  .  .   0,3212487 
r'     (3g2)     log.  o,325ioo8  (392)    .  .  .  o,325ioo8 


^  =tang'i.  (45''-|-u>)  log.  9  996 1 479 

45''-4-io=44''56'"ii',3o2  tang.  9,9990369 
w=  —  3"'48',698 

2t«=  —  7'"37',396 


sum  0,6463495 
half  o,323i748 


(r'r''ys  log.  0,9695243 
arith.co.log.  9,0304757 

tang.     7,34587„ 
same    7,34587» 
/=i''4.4»'53',75    (419)       sec.    0,00020 

tang2.2tc.sec./=o,ooooo492  log.     4,69194 


[5995(38)] 
I'l—V 


|.Iog.  {r'r") 


constant  log.  5,5680729 

9,970887     (43o)    log.  0,9987338 

same  0,9987338 

3xlog.sec./    (439)  0,0006066 

arith.  co.  log.     (433')  9,o3o4757 


901 

[.5999] 

(433) 

Firsl 

Approxi- 

malloil. 


(433) 
(433') 

(434) 

(435) 

(4311) 

(430 
(437) 


/=i''44"'53s,75 
4/=o52  26  875 


7)1  m 

(435) 


log.     6,5966228      (436) 


sec.       0,0003022 

sine     8,1834375 
same    8, 1834375 


sin2.4/.sec./=o,ooo23285  log.    6,3670772 

tang2.2«i,sec./^rf3,ooooo492     (436) 

I  ^0,00033777 
I  =0,83333333 

Z-|-|-  =  0,833571 10  subtract  log.     9,9309427 
mm    (438)  log.    6,5966228 

[5995(147)]       ft  =0,00047389  log.    6,6756801 

Corresponds  in  Table  VIII,  to  app.  log.  yy  =0,0004570 

'       log.  y  ^0,0002285 


To  find   q. 


T  (43i) 

t"  (43 1) 

2.log.  r'  (392) 

r  (4i2) 

r"  (4i2) 

y  (447) 

y"  (447') 

/  (439) 

y  (4i7) 

/"  (439) 

Corrected  Q  (256) 

Assumed   Q  (382) 


log.  g,3343i52 

log.  9,3 134223 

o,65o3oi6 

arith   co.  log.  g,6700i37 

arith.  co.  log.  g,67875i3 

arith.  co.  log.  9,9997715 

arith.  co.  log.  9,9996808 

secant  0,0003022 

secant  0,0009581 

secant  0,0002797 

log.  8,5475964 

log.  8,5477588 

Difference        — 0,0001624     ('*53) 


(430) 
(410) 

(441) 
(443) 
(443) 

(444) 

(44i) 
(44fi) 
(417) 

(447') 
(447  ) 

(447    ) 

(448) 
(449) 

(450; 


(151) 
(45S; 


(453) 


VOL.   III. 


226 


902 


APPENDIX,  BY  THE  TRANSLATOR; 


[5999] 

Spcolld 
Approxi- 
mation. 
(454) 

(455) 


Second  Approximation  to    P,  Q. 

With  the  corrected  values  ol  t,  t",  (43i),  and  the  computed  vahies  of  P,  Q  (448,  45i),  we  must  repeat 
that  part  of  the  calculation,  which  is  contained  in  (382 — 453),  in  order  to  obtain  a  nearer  approximation  to  the 
values  of  P,  Q.  We  shall  give  this  calculation  at  full  length,  and  in  the  same  form  as  in  the  first  process 
(382^453);  but  the  part  (422 — 43i)  relative  to  the  aberration,  is  given  with  sufficient  accuracy  ;  and  it  is 
not  necessary  to  make  any  correction  in  it.  The  labor  of  this  re-computation  is  much  decreased  from  the 
circumstance  that  the  same  form  of  calculation  is  retained,  and  the  results  are  not  much  varied. 


(456) 


(457) 


(458) 

(450) 
(460) 


P=      1,1995445      (448) 

a=    0,3543593     (364) 
d= —  1 ,3624994    (370) 


log'.  0,0790164 


P-\-a=     1,5539038  log.  0,1914342 

i'-(-d=— 0,1629549  log.  CO.  0,78793  26„ 

e  (373)  log.  8,3929633,. 

w=i3'^i5'"4i',oo  tang.  9,3733201 

J-'=      23  i3  j6  (35i) 

w-|-cr*=i3  38  54  16 


Q  (45i) 

c  (369) 

w  (458) 

Q'  (4o') 


log.  8,5475964 

log.  2,6907722 

sin.  9,36o58i8 

log.  0,5989504 


Hence  ihe  equation  (4i')  becomes, 
o,59895o4-|-4.log.sin.s— log.sin.(z— i3<'38"'54',i6)=o. 


To  find  z  hy  approximatiun  from  the  equation,     (459). 


(461) 

(402) 
(403) 


Assumed  value  of-, 
Its  log.  sine. 
Multiplied  by  4, 
Add  log.  Q', 

i4''35"' 
9,40103 

i4''33»' 
9,40006 

i4"33'"23» 
9,4oo25 

7, 604 1 2 
0,59895 

7,60024 
0,59895 

7,(5oioo 
0,59895 

Sum, 
(j— i3<i38™54',i6)sine, 

8,2o3o7 
8,21265 

8,19919 
8,19688 

8,19995 
8,19995 
0,00000 

Difference, 

— 0,00958 

-|-0,002  3l 

This  operation  is  much  abridged,  because  we  are  able 
to  assume,  in  the  first  operation,  the  value  of  z, 
computed  in  (3go),  which  varies  but  very  little  from 
the  result  here  found,  namely  z  =  i4''  33™  23'. 


To  find    T>    {-j-j),  and  the  factors    (4i",  4i"')- 


i?'.sin.<r'   (359) 


(464) 
(465) 
(466) 

(407)  "f  *  (35i)      o''23"'i3',i6 

(468)  z— <f*      =i4''io"'o9»,84 

(469)  AiE—Si{Zg^)=i^''ATo\'Ai 

(470)  2  (462)=i4  33  23  00 


log.    9,7362084 


i4  33'"23'      (462)    sub.  sin.    9,4002490 
r'  log.    0,3259594 


(471)         J+-«'-E-<r'=34  20  24  A 
,,,^3j  Its  log.  Bine  =9,7513596 


[T'r"-\-     S 


,4'£//_j'/(395)=;8<'54'"32»,75 

r=i4  33  23  00  f  [rr''^       j 
z-\-Ji'E^'—i'=73  37  55  75  \  ['■'■']  '^  ! 


Its  log.  sin.  ^9,6ooo9"5 


JÎ'.sin.J' 

P+a 

6  (392) 


Z-Î' 

(4i") 


(359) 
(457) 


log.    9,7262084 
log.    0,1914242 


log.  CO.    o,i38647i 
(468)  arith.co.sin.     0,6112070 


log.    0,6674867 
P    (456)  log.  subtract    0,0790164 

(4i"')  log.    o,58847o3 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


903 


To^ndp.p",  (48,49);       q,  q"(5o,  5i);      f ,  <:"  ;       r,  r"  (52,  53). 


[5999] 

Second 
Approxi- 


z-\-.rE—f' 

E 
E' 

(472) 
(4oi) 

(402) 

aril) 

X    (4o4) 
»  = 

P 

1,2340696 

(4o5) 

xpx  = 

3,2oi3348 

log.    0,6674867 


I 


(470) 


log.     o,5684703    (47,-)) 


sin.    9,75i3596z_(-.4'£"_^'      (472) 


sin.    8,6o83885 
arilh.  co.  sin.     O|goo3o84 


'og-  9>9275432 
log.  0,4864482 
log.     0,0913397 


log.    o,5o533ii 


q  =  xpx  —  ic  =  1,9672652  log.  0,2938639 

p  (4-7)  log-  9.9275432 

^  =  tang.^(52);  ^=23''i6'"4o',26  tang.  9,63368o3 

^^CE'  sec.  0,0368739 

q  (48i)  tang.  0,2938629 


E" 
El 


(4oi) 

(402) 


sin. 

sin. 

aritli.  CO.  sin. 


(4o4) 


log. 
log. 


9,6000975 

8,9341447 

o,9oo3o84 

0,0230209 
0,1592352 
0,541895g 


log.  o, 3307368 


«"=3,4825384  (4o5)  log 

>."  p"x''=  5,2984890                    log.  0,724l520 

q"  =  >."p"K"  —  x"  =  1,8 159506               log.  0,2591040 

P"     (477)                                          *"''•  '°g-  0,0230209 

1)" 

!-jy  =  tang.^"(53);     f  "=3o<io8'"3o»,24  tang.  9,7639169 


ÇI  =  O'E' 
q"     (48 1) 


log- 
log. 


0,0630914 
0,2591040 

0,3221954 


(474) 
(475) 
(470) 
(477) 
(478, 
(479) 

(480) 
(481) 
(483) 

(483) 

(484) 
(485) 
(486) 


To  find  the  arc    CO' =  2/',    in  the  triangle  CE'C". 


^=CE'  =  23''i6'n4o',26     (483) 
Çii—C'iEi  =  3o  08  3o  24     (483) 

Slim  28-,  =  53  25   10  5o  ; 
Diff.  2J>7  =    6  5i  49  98  ; 

s, 

iE'     (4i4) 


Sj  =26''42'"35',25 
Dt=  3  25  54  99 


sin.    8,7771576 
arith.  co.  sin.    0,347297 
cotan.     1,1996098 


^(C— C")      64''37'"5i',8o 
1(0-)- C")      86  45  55  3i 

SumisE'CC''=i5i  28  47   " 
Did.  is£'C"C=  2208  o3  5i 


tang.     o,324o65i 


-O7 

■St 

àE'    (4i4) 

.J  (C-\-C")  =86<'45'n55',3i 

E'Ci'C  (490) 
CE'  (487) 
E'         (4i6) 

of=CC"  =  7''34'»56',36 


(487) 


COS.  9,9992204 

arith.  co.  cos.  0,0490053 

cotan.  1,1996098    (488) 

tang.  1,2478355 

arith.  compl.  sin.  0,4239133 

sin.  9,5968064     (^83) 

sin.  9,0996916    (490) 

sin.  9,i2o4ii3     (451) 


To  find  the  arcs  CC'=2f"  ,    C'C"='2f,    (214,  21 5). 


r        (486)  log.  o,33o7368 

jl^.r'^    (473)  arith.co.log.  9,3325i33 

ifi=CC"        (491;  ein.  9,12041 

2f=C'C"  =3'^29'»oi',64  sin.  8,7836614 

2/"=CC'=4  o5  54  75     (493) 

Sum  is  2/=  CC"   =734  56  39 

Computed  CC"=7  34  56  36     (491) 


r"        (486) 

2f      (491) 

2/"=  CC'=4''o5"'54',75 


log.  0,3221954 

arith.  co.  log.  9,4115297 

sin.  9,i3o4ii3  (493^ 

sin.  8,854i364  .493) 

(494) 
(495) 


904 


APPENDIX,  BY  THE  TRANSLATOR  ; 


[5999] 

(490) 

Hpcoml 
Approxi- 
mation. 


(497) 
(497') 
(493) 

(499) 
(500) 

(501) 


(502) 
(503) 
(504) 

(503) 
(506) 
(507) 

(508) 

(5091 

(510) 
(511) 


(512) 

C513) 
(514) 


(515) 
(516) 
(517) 


To  find    y"     frotn  r,  r',  if",  t'—t,      (432—44?) 


log.=o,3259594 
Iog.=o,33o7368 


(466)  . 
(486) 


;o56 


-=tang4.  (45<'-(-u>)        log.    9,9952226 
r 

45i*_|_îo=44'*55'"i6%37    tang.  9 
«.=  —  4"'43',63 


2t0=  9"'27',26 

/"=  2<'o2™57',375     (493) 
tang2.2tt).sec/""^o,ooooo757 


0,3359594 
0,3307368 


r" 
sum  0,6566962  _=tang4.(45<'4-«))       log.    9,9962360 

half  0,3283481     "  —    ..  ■ 


{rr'y^  log.  0,9850443 
arith.  co.  9,0149557 


45*+i«=44''56"'i6',55  tang.  9,9990590 
w=  —  3'"43 


tang.     7,43936„ 

same     7,43936„ 

sec.     0,00028 


log.     4,87900 


(436')  constant  log.  5,568072g 

t'—t    (437)  log.  1,0778409 

same  1,0778409 

3X>og  sec./"     (5o3)  o,ooo8334 

J. log.   {rr')  arith.  co.  (497')  9!Oi49557 

m  m  log.  6,7395438 


f''=2do2"'5-j',3-j5    (499)     sec.    0,000277 
è/"=i  01  28   688  sine    8,2524236 

same    8,2524236 


sin3.jy"'^sec.y '=0,00031998 

tang2.2M).sec.y '=0,00000757 

Z^o,ooo32755 
s=o,83333333 


log.    6,5o5i25o 
(5oo) 


Z-f-|-  =  °>83366o88     log.  sub.     9,9209896 


m  m    (5o2) 
h  =  o,ooo6585o 


log.     6,7395438 


log.     6,8185543 


Corresponds  in  Table  VIII,  to  log.  y"  y"  =^  0,0006347 

log.  y"  =  o,ooo3i73 


To  find     y    from  r',  r",  rf,  ("—<'. 

-''  log.=  o,332i954  (486)    ...   0,3221954 


log.=  0,3269594 


(466) 


■II 


To  find    P. 

y"    (5ii)  arith.co.log.  9,999682 

log.  0,0002271 

log.  9,3i34223 

arith.  co.  log.  0,7656848 


y      (5n) 
t"   (447") 
T     (447'") 


Vt" 

Corrected  P=^,—    (235) 
y"T 

Assumed  value  of  P  (456) 


log.    0,0790169 
log.    0,0790164 


Différence  -|"°>°o°°°o5 


.  .  .   0,3269594 

sum  0,648 1 548 
half  0,3240774 


(r'r")-  log.  0,9722322 
arith.  co.    9,0277678 

tang.     7,33578„ 

same     7,33578h 

sec.     0,00020 


log.     4,67176 


2W^=  —   7'"26^',90 

/=i''44"'3o',82    (493) 

tang2.2M). sec./ =0,00000470 

(436')  constant  log.  5,6680729 

f'—t'    (437)  log.  0,9987338 

saine  0,9987338 

3X log. sec./    (6o3)  0,0006021 

^.log.  {r'r")  arith.  co.     (497')  9,0277678 

m  m  log.  6,6939104 

/=  I ''44""  3os,82     (499)     sec.  0,0002007 

4/=o"'62'"i6»,4i  «'°^  8,1818625 

same  8,1818625 


secS.J /.sec./^o,ooo23ii6  log.     6,3639067 

tang2.2Ui.sec./=o,ooooo470     (600) 

I: 

5  . 


=  0,00023586 
=  0,87333333 


Z-)-|=  °.833569i9  log,  sub.  9,9209417 
7/1  711        (602)  log.  6,6939104 


h  =  0,00047094             log. 

6,6729687 

orrespond 

i  in  Table  VIII,  to  log.     yy 
log.  y 
To  find  Q. 

0,0004541 

0,0002271 

1 

(447') 

log- 

9,2343i52 

t" 

(447") 

log. 

9,3 1 34223 

2.log.  r' 

(466) 

0,6619188 

r 

(486) 

arith.  co.  log. 

9,6692632 

r" 

(486) 

arith.  co.  log. 

9,6778046 

y 

(6.1) 

arith.  co.  log. 

9.9997729 

y" 

(6.1) 

arith.  co.  log. 

99996827 

/ 

(5o3) 

sec. 

0,0002007 

/ 

(49  >) 

sec. 

0,0009614 

f 

(6o3) 

sec. 

0,0002778 

Q 

Assumed  value  of  Q  (456) 

Difference 


log.     8,54''6o96 
log.     8,54-i6964 

-f-       0,0Û00l32 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


905 


Third  Approximation  to    P,  Q. 


[5999] 

Third 

Approxi- 

umtioD. 


With  the  computed    values  of  P,    Q  (5i2,    5i5),    we  must  ap;ain  repeat  the  operation,  as  in  (456— 5i7)  to       (518) 
obtain  the  final  vahics  of  P,  Q.     The  form  of  calculation  is  the  same  as  in  the  last  process,  anil  the  numbers 
vary  but  very  little,  so  that  the  calculation  is  repeated  with  great  facility  ;    and  it  serves  as  a  verification  of 
the  process. 


P=  1,1995459  (5l2) 
a=  o,35435g3  (364) 
d^ — 1,3624994     (370) 


loff.  0,0-90169 


P-(-a=  1,5539052  log.  0,1914546 

P-|-d= — 0,1629535  log.  CO.  0,7879363,, 

e     (373)  log.  8,3g2g633n 

w=i3<fi5'"4i ',44  tang.  9,3723242 

J"=   23  i3  16  (35i) 
w-)-<f '=i3  38  54  60 


Q  (5i5) 

c  (36o) 

W  (522) 

Qi  (4o') 


log- 
log. 


8,5476096 
2,6907722 
9,36o5857 


log.  0,5989675 


Hence  the  equation  (4i')  becomes, 

0,598967  5-|-4.1og.sin.ï — log.sin.(« — i3''38"'54',6o)=o. 


(519) 


(520) 
(521) 

tS22) 
(523) 

(524) 


To  find  z  hy  approximation  from  the  equation,    (523). 


Assumed  value  of  r. 
Its  log.  sine, 

i4''33"'23^ 
9.40025 

l4''33"'23^8 
9,4002555 

i4''33'»23»,72 
9,4002548 

Multiplied  by  4, 
Add  los.  Q', 

7,60100 
0,59897 
8,19997 
8,19989 
-|-o,oooo8 

7,t3oiO220 

0,5989675 

8,1999895 
8,1999982 

— 0.0000087 

7,6010192 
0,5989675 

Sum, 

(:— i3<'38"'54'.6o)sine. 

8,1999867 

8,1999875 

—0,0000008 

Difference, 

(525) 
The     value    of    z,    obtained    in    (462),   is  here 
assumed  as  the  first   operation,  and  by  a  very  easy 
calculation  we  find     2:=i4''33"'23^,72  nearly.  (50g) 

(527) 


To  find    r'    {n),  and  the  factors   (4i",  4i"')- 


R'.im.i'  (464)  log.    9,7262084 

Ï  i4''33"'23»,72  (525)  sub.  sin.    9,4002548 

rl 


log.     0,3259536 


t*  (35i)      o''23"'i3',i6 


2— <f*=i4''io'"io«,56 


.«'£— J' '(469)=i  9''47'"o  I ',47 
z  (526)=i4  33  23  72 


z-\-A'E—i'=M  20  2  5  19 


Its  log.  Bine  =g,75i36i8 


.4'£//_j/(469)=8''54°'32',75 
2=i4  33  23  72 


z-(-.4'£"— ^'=23  27  56  47 


Its  log.  sin.  =9,6001010 


P'.sin.J'  (464)       log.  9,7262084  (528) 
P-(-a    (520)      log.  0,1914246  (529) 

b  (466)  arith.co.log.  0,1 386471  (530) 

z—i*         (532)  arith.co.sin.  0,6112011  (531) 

^rr7!l-'4   (4'")  'og-  0.6674812  (532) 

P  (519)  log.  subtract  0,0790169  (533) 

H-^.r'^   (4im)  log.  0,5884643  (534, 

(535) 

(S3e) 


VOL.  III. 


227 


906 


APPENDIX  BY  THE  TRANSLATOR  ; 


[5999] 

Third 
Approxi- 
mation. 

(537) 

(538) 
(539) 
(540) 


To  find  p,  p",  (48, 49)  ;       q,  q"  (5o,  5i)  ;      ^,  ^"  ;       r,  r"  (52,  53). 


I  [rV]       S 
z-\-A'E—i' 
E 
E' 


(532) 

(536) 
(475) 
(476) 


log.  0,6674812 

sin.  9,75 1 36 1 8 

sin.  8,6o83885 

cosec.  o,9oo3o84 


(541) 
(542) 

(543) 

P 

X  (478) 

x  =  1,2340696 

xpx  =3,2oi3io4 
q  =  xpx  —  «  =  i  ,9672408 
P  (54i) 

^  =  tang.^=23''i6»4o',62 

^=CE' 
q  (545) 

r 

(479) 

log 

log. 
log. 
log- 
log. 
.  sub. 
log. 

tang. 

sec. 
tang. 

log. 

9,9275399 
0,4864482 
0,0913397 

(544) 
(545) 
(546) 

0,5053278 
0,2938575 
9,9275399 

(547) 

9,6336824 

(548) 
(549) 

0,0368743 
0,2938575 

(550) 

o,33o73i8 

(534) 


log.    0,5884643 


x-\-AiE'i-S->       (536) 
E'l             (475) 
E'              (476) 

sin. 

sin. 

cosec. 

9,6001010 
8,9341447 
o,goo3o84 

P"                  log. 

X"   (478)              log. 

x"=  3,4825384  (479)  log. 

o,o23oi84 
0,1592352 
0,5418959 

^"p"K"=  5,2984585 

log- 

0,7241495 

q"  =  x"p"  x"  —  x."=  1,8159201 
p"  (54 I) 

p" 

!-j5  =  tang.4-"=3o''oS'"3i»,23 

f "  =  C"Ei 
q"  (545) 

log,  sub. 
log- 
tang. 

sec. 
log. 

0,2590967 
o,033oi84 

9,7639217 

0,0630926 
0,2590967 

r" 

log. 

0,3221893 

(551) 
(552) 
(553) 
(554) 
(555) 
(55C) 
(557) 


To  find  the  arc    CC"  =  if',    in  the  triangle  CE'C". 


^=CE'  =  23'^i6'"4o',62     (547) 
Çii=C"E'  =  3o  08  3 1  23    (547) 


Sum 
Diff. 

2Z»8  = 

53  25 
6  5i 

II  85; 
5o  61  ; 

iE' 

(488) 

e 

4(C-c")= 

64'f37'»53' 
8645  55 

,3r 
33 

S^  =26'^42'"35s,93 
Xio=  3  25  55  3i 


sin.    8,777  It 

arith.  co.  sin.    0,3472948 

cotan.     1,1996098 


tang.    0,3240734 


(558)  SumisE'CC"=i5i  23   48  64 

(559)  Difi.is£'C"C=  2208  02  02 

(560) 


-Da 

«8 

è-E'    (488) 


i(,C-\-C")  =86<'45">55',33 


cos.    9,9992204 

arilh.  co.  cos.    0,0490060 

cotan.     1,1996098 


tang.     1,2478362 


E'C'C  (559) 
CE'  (55 1) 
E'  (490) 


arith.  compl.  sin.  0,4239210 
sin.  9,5968081 
sin.    9,0996916 


2f=Ca'  =  7''34"'56»,95 


sin.    9,1204207 


To  find  the  arcs  CC'=7fii ,    OC"=-if,    (214,  2i5). 


(561) 
(562) 

(563) 
(564) 


r        (55o)                          log.  0,33073 1 8 

jfrin-'''^    (537)             arith.co.log.  9,3325x88 

•ifi=CC"        (56oJ                             sin.  9,1204207 

2/=3'^29'»oi',92               sin.  8,7836713 

2/"=4  o5  55  07     (56i) 

Sum  is  ■if=^  34  56  99 
Computed  above  =-j  34  56  96     (56o) 


r"        (55o) 

(56o) 
2y"=4''o5'"55>,07 


log.  0,3221893 

arith.  co.  log.  9,4ii5357 

sin.  9,1204207 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


907 


To  find     y"    from   r,  r',  nf",  t'—t.     (496—511). 


log.  0,3259536 
log.  0,33073 18 


r' 

-=!tang4.(45ii-|-u")  log.  9,9952218 

45*f  io=44''55'"i6',32  tang.  9,99880545 
tc=  —  4°'43',68 

2tc=  —  9'"27',36 


(53o)  .  .  .  0,3259536 
(55o)  .  .  .  o,33o73i8 


sum  0,6566854 
half  0,328342- 


{rr')i  log.  0,9850281 
arilh.  co.  9,014971g 


tang.  7,43943,1 

same  7,43943n 

/"=2''o2"'57',535     (562)     sec.  0,00028 

log.  4,87914 


tang2.2u?.secy  "^0,00000757 


(436') 


t'—t 


constant  log.  5,5680729 

(437)      log.  1,0778409 

same  i  ,0778409 

SX'og-sec.y"     (572)  0,0008337 

â.log.  (rr')            arith.  co.  (566')  9,0149719 


log.     6,7395603 


/"=3(f02'"57*,535     (568)     sec.    0,0002779 

^/"=i  01   28  768  -sine    8,252433: 

same    8,252433i 


siQ2.4/".sec/"^o,ooo32ooo  log.    6,5o5i44i 

tang2.2ic.sec/"=o,ooooo757    (569) 

/=o,ooo32757 
5=0,83333333 

6       

J-|- ^=0,83366090    subtract  log.     9,9209895 
mm    (571) 


7j=o,ooo65S52 


log.    6,7395603 
log.    6,8185708 


Corresponds  in  Table  VIII,  to  app.  log.  y"y"^o,ooo6348 

log.  y"=o,ooo3i74 


To  find    y   from    r',r",    2/,  t"—t'. 


log.  o,32  2i8g3 
log.  0,3259536 


=tang4.(45H-«')  log-  9.9962357 

45''-}-u'^44''56"ii6»,53  tang,  9,99905892 
w=  —  3'"43',47 

2W=:  —  7'»26',94 


To 

find 

P. 

y" 
y 

(580) 
(580) 

ari 

t" 

T 

(447") 
(447'") 

arith  co.  log.  9,9996826 

log.  0,0002271 

log.  9,3i34223 

log.  0,7656848 


Corrected  P=  ^    (235) 
y"r 

Assumed  value  of  P   (5i9) 


log.     0,0790168 
log.     0,0790169 


Difference  : 


-0,0000001 


(55o)   .  .  .   0,3221893 
(53o)    .  .  .  0,3259536 

sum  0,6481429 
half  0,3240714 


(/r'')^  log.  0,9722143 
'arith.co.log.  9,0277857 

tang.    7,33582„ 
same    7,33582^ 
f  =  id44m3o',g6    (56i)        sec.    0,00020 

tang2.2tc.sec./=o,ooooo470  log.    4,67184 

(436')  constant  log.  5,5680729 

l"—t'  (437)  log.  0,9987338 

same  0,9987338 

3xlog.sec./    (572)  0,0006021 

arith.  co.     (566')  9,0277857 


[5999] 


(5C5) 

Third 

Approsi- 

matiuil. 


(566) 
(566') 

(507) 

(568) 
(569) 

(570) 


g.log.  (r'r") 


/=i'*44"3os,96 
4/=o52  i5   48 


m  m 

(568) 


log.      6,5939283       (571) 


sec.    0,0002007 

sine    8,1818622 

same     8,1818622 


sin2.4/.sec./=o,ooo23ii7  log.    6,363925i 

tang2.2W),sec./=o,ooooo470    (569) 

I  =0,00023587 
I  =0,83333333 

Z-|-|  =  0,83356920  subtract  log.    9,9209417 
7nm    (571)  log-    6,5939283 


(572) 
(573) 

(574) 
(575) 
(576) 

(577) 


h  ^0,00047096 
1  Table  VIII,  to  app. 

log. 

log-  yy  = 

6,6729866 

(578) 

Corresponds  ii 

=0,0004541 

(579) 

To  find 

Q- 

log.  y  = 

=  0,0002271 

(580) 

T 

(447') 

log. 

9,2343 1 52 

," 

(447"; 

log. 

9,3i34223 

2.log.  r' 

(530) 

0,6519072 

r 

(55o) 

arith. 

CO.  log. 

9,6692682 

r" 

(55o) 

arith. 

CO. log. 

9,6778107 

(581) 

y 

(580) 

arith 

CO.  log. 

9,9997729 

(582) 

y" 

(58o) 

arith 

CO.  log. 

9,9996826 

(583) 

/ 

(572) 

secant 

0,0002007 

/' 

(56o) 

secant 

O,ooog5i4 

/" 

(572) 

secant 

0,0002779 

Corrected  Q 

log. 

8,5476091 

(584) 

Assumed  value  of  Q 

(5i9) 

log. 

8,5476096 

(585) 

Difference= — o,oooooo5     (586) 


The  differences  between  the  assumed  and  computed  values  of  P,  Q  (583,586J,  are  so  very  small  that  it  will 
not  be  necessary  to  repeat  the  operation  ;  and  we  may  suppose  the  expressions  of  r,  ri'J  ',  deduced  from  (his 
last  calculaUon  to  be  their  true  values  ;  from  which  we  may  deduce  the  elements  ot  the  orbit,  in  the  following 


(557) 


908 

[5999] 

(388) 
(589) 


APPENDIX,  BY  THE  TRANSLATOR  ; 

To  compute  the  elements  of  the  orbit. 
We  have  for  this  purpose     log.  r=o,33o73i8  (55o)  ;    log.  r"=o,322i8g3  (55o)  ;  2/'=7''34m56,.96  (56o)  ; 
t=Oct.  5''''^',45i989    (429)  ;  «"=Oct.  27''*^',385899  (429),    or    i"-(=2i''^'",9339io.    With  these  data  we  may 


(601) 

(602) 

(603) 

(604) 
(605) 

(606) 
(607) 

(608) 

(609) 

(610) 

(611) 
(612) 
(613) 
(614) 

(615) 
(616) 
(617) 
(618) 


Computa- 
tion of  the 
eleiaents. 

(590) 
(591) 

déterra 

r" 

r  — '=^"8 

45<'-|-ic= 
w= 

310= 

Ine  the  elements,  by  the  meth 

To  find    ï  =  sin2.i^.     [5ç 
r'l             log.=o,322i893 
r              Iog.=o,33o73i8 

«.(45''-H«)      log.    9,9914575 
44''5i'»32',85  tang.  9,99786438 

od  explam( 

95(187)]. 
(588)  .  .  . 
(588)  .  .  . 

sum 
half 

{rr"^  log 
arith.  co. 

tang. 

same 

)         sec. 

log. 

) 

)          log- 
same 

)  arith. CO. 

log. 

sec. 
sine 

same 

;d  in  [0993] 

0,3221893 
o,33o73i8 

• 

Tc 

2/'= 

a 

find 

=■,-34'' 
\/—e 

To  find    a,    [5995(58)]. 
g         (612)  arith. compl.log.sin. 

same 
?n2 
—       (608)                            log. 

2                                              log. 
/'        (595)                            cos. 

VS^    (591")                           log. 
a                                             log. 

p     and     e  =  sin.  »,     [5g95(6o, 

7c            (54)          arith.  co.  log. 

t'l—t     (5y6)          arith.  co.  log. 

>-r"       (5gi')                          log. 

'56s,g6     (588)                            sin. 

yi          (606)                           log. 

S/P       [5995(60)]                   log. 
Va      (594)                           log. 

î=cos.?  ;     f=i4''i2ino5',3       cos. 

1,2621295 

(591') 
(591") 

0,6529211 
0,3264606 

1,2621295 
7,27i6i36 

(59S) 
(592) 

=  _  8"'27',i5 

=  _I6"■54^3o 

/'=3-i47«.28',48      (58f 

tang2.2t/).sec/'=o,oooo2423 

constant  log.     (436 
<i'_i=2i,9339io     (589 

3Xlog  sec./'     (595 
f.Iog.  (rr")       (592 

TO  m 

/'                         (595 
èy'=i<'53'"44',24  (595 

0,9793817 
9,0206183 

o,3oio3oo 
9,9990486 

(593) 
(594) 
(595) 

7,6917447 
7,6917447 
0,0009514 

0,3264606 
0,4224118 

(595) 

5,38444o8 

12.9)]- 

(596) 

5,5680729 
i,34iii6o 
i,34iii6o 
0,0028542 
9,02o6i83 

1,7644186 

8,658884o 
0,6529211 
9,1204208 

(597) 

7.2737774 

0,0010819 

(598) 
(599) 
(600) 

0,0009514 
8,5195500 

8,5195500 

0,1977264 
0,21 12059 

9,9865205 

sIn2.i/'.sec./'=o,ooi0966i  log.     7,o4oo5i4 

tang2.2M).sec.y^o,oooo2423    (595') 

Z=0,OOII2084 

1=0,83333333 
Z-}-§  =  o,834454i7     log.  sub.    9,9214025 


S 


m  m    (597) 

h  =O,00225l0 


log.    7,2737774 


log.    7,3523749 


Corresponds  in  Table  VIII,  to  y'  y'=  o,0O2i638 
mm    (597)  log.     7,2737774 


To  find     G,  F,  v,  «",  u,  u",    [5995(65,66,  &c.)]. 
f       (600)  sub.  sine    9,3897547 

(612)  cos.    9,9993497 

cos.g'.cosec.?=4,0700o56        log.     0,6095950 

— •;?'     (591") 
a      (594) 

/'      (592') 

(f       (60 1  ) 

■V—cosf'.cosec.f^ — 3,2609391      log.    o,5i33427» 


ma 

—  =0,00186902     log.     7,2716136 

Z  ^0,001 12084     (602) 

7772 

X  =—jr—l=sin^.ig  ^o,ooo-j48i8     log.    6,8740061 

àg=i'*34'"02*,64   sin.    8,4370o3o 
g=3'io8'"o5',28 

After  finding     a    in  the  second  column  (594),  we  may 

find  the  mean  daily  motion  in  seconds  from  [5995(67)]. 

a    (594)  log.  ar.  co.     9,5775882 

its  half    9,7887941 

constant  log.    3,55coo66 

Daily  motion    824',877  log.     2,91638891 


log.    0,3264606» 
ar.co.log.  9,577588a 

cos.     9,9990486 

cosec.  0,6102453 


[5g95(65)]  cos.  G^    0,8090665   log.  9,9079842 


[5995(41,47)]    G=  324''oo'"i7.,4  sin.  9,7691682» 

/'    (595)  sin.     8,820342a 

g    (612,591)    3''o8"'o5',3  cosec.  1,2621295 

F=    3i4''42"'5i'',4  sin.    9,8516399» 

/'=        347  28  5  (595) 

V  =F—fi=    3io55  22  9  [5995(i3)] 

i,"=F-(-/'=     3i8  3o  19  9  [5995(1 4)] 

H=G — g=    320  52  12   I  [5995(i5)] 

u"=G+g=    32708  22  7  [59g5(i5)] 


COMPUTATION  OF  THE  ORBIT  OF  A  PLANET. 


909 


We  may  remark  that  the  expression  of  cos.  G  =  0,8090665  (608),  corresponds  to  G=:  3î4''oo"'i7M  or  to 
G=  SS'^SgiTiîiî'.e.  The  first  of  these  expressions  is  to  be  used  as  in  (610),  because  the  corresponding  values  of 
v,v"  (6i5,6i6),  are  in  the  fourth  quadrant  of  the  true  anomaly,  where  the  radii  r,  r"  are  decreasing,  as  in  (588); 
but  tlie  other  value  of  G,  gives  v,  v",  in  the  first  quadrant  of  the  true  anomaly,  when  the  radii  r,  r"  are 
increasing.  The  mean  anomalies  nt=u—e.sin.u,  »i("=u"— e.sin.u"  [5985(7)],  corresponding  to  the  first 
and  third  observations,  may  be  found  in  the  following  manner. 

To  find  nt,    [5985(7)].  To  find  nV,    [6985(7)]. 


e    (601) 

radius  in  seconds, 

— sin.u  (617)  32o''52"'ia',i 


log.  9,3897547 
log.  5,3i4425i 
sin.  9,8000855 


— e.sin.«  =  3i934»,9^  8  52  149    log.  4,5o42653 


Mean  anom.     nf  =329.44  27  o 


e    (601) 

radius  in  seconds, 

— sin.a"  (618)  327''o8"'22«,7 


log-  9.3897547 
log.  5,3i4425i 
sin.    9,7344746 


-e.sin.M"  =  27457^,1=    73737  I         log.    4,4386544 


Mean  anom.    nt"  =334  45  Sg  8 

To  find  Ui  ?. 
We  may  find  the  longitude  of  the  node  u,  and  the  inclination  ?,  of  the  orbit  to  the  ecliptic  ;  by  means  of  the 
triangle    'oJlC,   in  which  we  have  given, 

the  angle  u.4C=}.=i6''oo'"oS',38     (3i4)  ;  the  angle  uC.5=£'CC"=i5i''23"'48",64     (558); 

.;3C=.4£'— C£'=33''I2»"29^78— 23''i6'"4o',62=9''55'"49',i6       (33o,  55i)  ; 
to  find  the  angle  u,  and  the  sides  uC,  u.3,    by  Napier's  formulas  [i345'°'"J. 
■uJiC=  i6<'oo'»o8%38 


uCjî=r5i  23  48  64 


Sumis  285=167  23  57  02 
Diff.is2Z)9=i35  23  4o  26 


S,=  83''4i'"58',5i 
X)9=  67  4i  5o  i3 


-D9 

4./ÎC   =    457  54  58 

è(U.^— uC)=  4  37  23  46 
è(u.«+t5C)=i6  43  18  36 
Diff.  is  uC=  12  o5  54  90 


sin.     9,96623 16 

arith.  co.  sin.    o,oo263io 

(628)  tang. 


tang.    8,9077624 


Sum  is  u-5=  21  20  4i 
Lon.^(3o2)=  12  28  27  76 


Diflt.  is  u=35i  07  45  9 


uC^  i2''o5'"54',9 
u  (635)  is  ^35 1  07  45  9 


Sum  is  long.  ofC=    3  i3  4»  8 

Sub.»  (6i5)=3io  55  23  g 

Long,  perihelion 


COS.    9,5792122 

arith.  co.  cos.     0,9596291 

tang 


8,g388gg8     (631) 


tang.    9,4777411 


S, 
à./ÎC(628) 

4(u.«+uC)=i6''43'"i8',36  

vC    (632)  sin.  arith.  co.     0,6786204 

uv3  0(629)  sin.    9,4403996 

AC   (628)  sin.    9,2366642 

^uC=i3''o6'"36',o  sin.    9,3556842 


52  18  17  9 

From  the  time  of  the   last  observation,  corrected  for  aberration  as  in  (429),  October  27,  385899   to   the  epoch 

January  I,  i8o5,  the  interval  is  64  ^'^,6i4ioi.     Multiplying  this  by  the  daily  motion  824^,877  (618),  we  get  the 

mean  motion  in   that  interval,  i4''48'"i8s,6.     Adding  this   to   ni"  =  334''45"'59s,8  (625);    we  get   the  mean 

anomaly    at  the    epoch,   equal   to   349''34"'i8*,4.      This  last  expression  being  added  to   the    longitude  of  the 

perihelion  52''i8"'i7',g  (636),  gives  the  mean  longitude  at  the  epoch  4i''52"'36',3.     Hence  we  have  the  following 

elements  of  the  orbit. 

Elements  of  the  orbit  of  Juno. 

Log.  of  the  mean  distance  a=    0,4224118     (5g4). 

Log.  of  the  semiparameter  p  =    0,3964528     (5g8). 

Log.  of  the  excentricity  e=   9,3897547     (601). 

Daily  runlion  824',877     (618). 

Inclination  of  the  orbit  to  the  ecliptic  =  i3''o6"'36',o     (634). 

Long,  of  the  ascending  node  I7id07'n45«,9     (635). 

Long,  of  the  perihelion  in  the  orbit         52''i8'"i7',g     (636). 

Mean  longitude  at  the  epoch  4i''52"'36',3     (639'). 

With  the  daily  motion  824' ,877(618),  the  planet  would  describe  the  whole  circumference  360*  in  about  i57i 
days,  which  represents  the  time  of  revolution  of  the  planet.  If  we  compare  these  elements  of  the  apparent  orbit, 
corresponding  to  the  epoch  i8o5,  with  those  in  [40791],  corresponding  to  the  year  i83i  ;  we  shall  find  that  they 

VOL.  III.  228 


ji'a. 


[5991'] 

(010) 
(620) 
(621) 

(622) 


(623, 

(624) 
(025) 

(626) 

(627; 
(62«) 

(629) 
(63«; 


(63S) 
(633) 

(63H) 
(635) 
(636) 

(637) 
(638) 
(639) 

(639-) 


(640) 

(64)) 
(642) 
(643) 

(044) 
(645) 
(646) 

(647) 


(648) 


910  APPENDIX,  BY  THE  TRANSLATOR. 


[5999] 

(649) 


agree  as  well  as  could  be  expected,  taking  into  consideration  tiiat  all  the  calculations  in  this  article  are  deduced 
"(650)     from  the  motion  of  the  planet  in  a  geocentric  arc  of  less  than  four  degrees.    These  elements  were  sufficiently 
accurate  to  trace  the  path  of  the  planet  for  several  days,  until  other  more  distant  observations  could  be  obtained, 
for  correcting  them. 


This  method,  like  all  others  of  a  similar  nature,  requires  some   modification  in  particular  cases.     First. 

(651)  When  any  one  of  the  three  geocentric  places  of  the  planet  coincides  with  the  heliocentric  place  of  the 
earth,  or  with   its  opposite  point  at  that  time  ;  because  then  the  arc,  connecting  this  geocentric  place  of  the 

(652)  planet,  and  the  corresponding  heliocentric  place  of  the  earth  becomes  indeterminate.      Second,     When   the 
(553)     geocentric  places  ot  the  planet  in  the  first  and  third  observations  coincide.     Third.  When  the  three  geocentric 

(654)  places  of  the  planet  are  situated  in  a  great  circle,  passing  through  the  heliocentric  place  of  the  earth  in  the 
second  observation.     In  the  first  of  these  cases  the  situation  of  one  of  the  great  circles  AB,  A'B',  Jl'' B" ,  remains 

(655)  indeterminate  ;  in  the  second  and  third  cases,  the  situation  of  the  point  B*  is  indeterminate  ;  and  in  these  two 
last  cases,  the  defect  is  inherent  in  the  problem  itself,  and  cannot  be  rectified.     We  must,  therefore,  in  selecting 

(656)  the  observations,  which  are  to  be  used,  avoid  those  which  are  at  the  same  time  near  the  node,  and  near  the 
conjunction  or  opposition  with  the  sun  ;  we  must  also  avoid  those  observations  in  wliich  the  geocentric  place  of 

(657)  (]jg  planet,  in  the  third  observation,  is  near  to  that  in  the  first  observation  ;  finally,  we  must  reject  those  in  which 
all  three  of  the  observed  places  of  the  planet  lie  nearly  in  a  great  circle  passing  through  the  heliocentric  place 

(658)  of  the  earth,  in  the  middle  observation.  We  may  easily  rectify  the  rules  in  the  first  case  (65i),by  supposing  the 
points  E,  E',  E",  figure  92,  page  874,  to  coincide,  and  then  finding  this  point  of  coincidence  by  means  of  the  two  of 

(659)  t]jg  three  arcs  AB,  A'B'  or  A''B",  which  are  given   in  position  and  magnitude  ;  supposing  the  other  arc  to  be 

(660)  infinitely  small,  but  taking  it  in  the  direction  towards  the  common  point  E,  For  example,  if  the  points  JÎ,  B, 
coincide,  we  may  suppose  the  arc  AB  to  be  infinitely  small,  and  that  it  is  taken  in  the  direction  of  the  great  circle 

(661)  ABE.     It  being  evident  that  this  small  change  in  the  place  of  the  planet,  at  the  time  of  the  first  observation, 

^662)      can  produce  no  sensible  effect  in  the  result  of  the  calculation.     In  this  ease  the  factor     -^ — ,  ^  ' , r  ,       which 

'  sm.{AE'—J-) 

occurs  in  the  expression  of    a     (32)  becomes,     - — —j- ,    which  may  be  put  equal   to  nothing,  on    account  of 

(663)  the  extreme  smallness  of  sin  J";  hence  we  have  a^o  (32).  This  value  of  a  is  to  be  substituted  in  (35,4o), 
and  we  shall  get  the  value  of  w,  to  be  substituted  in  (4i')  ;  then  the  calculation  is  to  be  completed  in  the  usual 
manner.  The  method  of  proceeding  is  nearly  the  same,  when  the  points  A",  B",  coincide  in  the  third  observation  ; 

(664)  and  as     a,  6,     (32,33),  become  infinite,  because     sin.<r":=o,     we  must   put  as  in  (42)     a=66,  ;    and     tang.w 

(4o)  changes  into     tang.w,     (43);  also  the  factor,        7~       (4i"))    changes  into    -  =  6,.     When    the     points 

(665)  A',  B',  coincide,  we  have     6=0     (33);  hence  (4o)  becomes,     tang.w=  —  ' — F»^ — ^^^S-^*)  <""    w^— tf»; 

and  so  on  for  the  other  quantities.     It  is  unnecessary  to  enter  more  minutely  into  the  consideration  of  these 
(566)      uncommon  cases,  as  the  method  of  proceeding  is  sufficiently  obvious. 

In  all  the  preceding  calculations,  we  have  supposed  the  orbit  to  be  wholly  unknown,  at  the  commencement 
(lOT)      of  the  calculations;   but  it  is  evident  that  the  same  method  can  be  observed  for  correcting   the   approximate 

(668)  elements,  in  a  manner  similar  to  that  in  [825 — 829].  Taking  P  and  Q  for  the  unknown  quantities;  and  then 
separately  varying  each  of  them,  by  a  small  quantity,  in  two  successive  operations,  so  as  to  obtain  two  equations, 
similar  to  [82g],  for  correcling  the  assumed  values  of  P,  Q.  This  method  is  so  plain,  that  it  requires  no 
particular  illustration.     We  may  however  remark  that  when  the  arcs  2/,  2/',  2_/  "    are  large,  the  assumed  values 

(669)  of  P,  Q  (269)  may  not  be  sufficiently  accurate  for  the  first  operation,  and  then  we  may  use  the  expressions 
(670),  computing  the  values  roughly,  by  means  of  the  approximate  elements,  which  have  been  previously  found. 

r.sin  2  /  "  4r'*.  sin.  /'.sin./'" 

r".sm/  p.cos.J' 

This  value  of  P  is  easily  deduced  from  (38,  go)  ;  and  if  we  multiply  the  expression  of  Q  (3g),  by  that  of  p   (247), 
(CTl)     and  the  product  by  [c  1'],  we  get  p.Q  [rr"]=S  rr'i  r".  sin. /.sin./',  sin./".     Substituting  in  the  first  member, 
the  v.ilue  of   [r  r"]     (go),  and  then  dividing  by    2  pre' .sin./',  cos. /',     we  get  Q  (670). 


TABLE  I.  — OF  SQUARE  ROOTS. 

The  proposeil    number  is  to  be  found,  as   far  as  Oic    scconrl   decimal   jilaco,  in  tlie  side  cobimn  of  the  (able,  and  the  third 
decimal  at  the  top  of  one  ot  the  vertical  co]\i]iMis;  ilie  number  oorrespoiidins  is  tlio  jeciuired  root. 


o.oo 
o.oi 
o.o:! 
o.o3 
0.04 

o.o5 
o.oG 

O.OT 

0.08 
0.09 

O.IO 

O.I 

0.12 

O.I  3 
0.14 

O.I  5 
0.16 
0.17 
0.18 
019 

0.20 
0.21 
0.22 

0.23 

0.24 

0.25 

0.26 

C.27 

0.28 
C.29 

o.3o 
0.3 

0.32 

0.33 
0.34 

0.35 
0.36 
0.37 
0.38 
0.39 

0.40 
0.41 
0.42 
0.43 
0.44 

0.45 
0-46 
0.47 
0.48 
0.49 


0 


1 


o.oooovl  o3i62 
II.  1 0000  10488 
0.14142  14491 
0.1702!  17607 
0.20000  20246 


0.25361 
0.2449") 
0.26458 
0.28284 
o.3oooo 

0.31623 
o.33i66 
0.34641 
o.36o56 


0.37417  37550 


o.5o 
o.5i 
0.52 
0.53 
0.54 

0.55 
o56 
0.57 
0.5S 
0.59 


22583 
24(598 
26646 
28460 
3oi66 

31780 
333i7 
34785 
36194 


0.38-30 
0.40000 
o.4i23i 
0.42426 
0.43589 

0.44721 
0.45826 
0.46904 
o  47958 
048990 

o.Soooo 
0.50990 
0.51962 
o. 5291 5 
o  53852 

0.54-72 
0.55678 
o.  56569 
0.57446 
o.583io 

0.591 61 

0.60000 

0.60S28 

0.6164. 

0.62450 

0.63246 
o.64o3i 
0.64807 
0.65574 
0.66332 

0.67082 

0.67823 

0.6855 

0.69282 

0.70000 


38859 
4oi25 
41352 
42544 
43704 

44833 
45935 
4701 1 
48062 
49092 

5oroo 
5io88 
52o58 
53009 


04472 
10954 
14832 
1788g 
20494 

22804 
24900 
26833 
28636 
3o332 

31937 
33466 
34928 
36332 
3-683 


53944  54037 


0.7071 1 
071414 
0.72111 
0.72801 
0.73485 

0.7416:- 
0.74833 
0.75498 
0.761 58 
0.76811 


54863 
55-6- 
56657 
57533 
58395 

59245 
6oo83 
6091  o 
61725 
62530 

6332 
64i  og 
64885 
6565i 
66408 

67157 

67897 
6862g 

69354 
70071 

70781 
71484 
72180 
72870 
73553 

74229 
74900 
75565 
76223 
7687- 

1 


4o24g 
41473 
42661 
438i8 

44944 
46043 

47117 
48166 

49193 

50200 

5ii86 
52i54 
53io4 


55857 
56745 
57619 
5848i 

59330 
60166 
60992 
61806 
62610 

634o3 
64187 
64962 
6572T 
66483 

67231 
67971 
68702 
69426 
70143 

70852 
71554 
72250 
72938 
73621 

74297 

74967 
7563i 
76289 
76942 


o5477 
ii4o2 
i5i66 
1 81 66 
20736 

23o22 

25lOO 

27019 

288 

30496 

32094 

336i5 
35071 
36469 
37815 

3gii5 
4o373 
41593 
42778 
43932 

45o56 
461 52 
47223 
48270 
49295 

50299 
51284 
52249 
53198 


o6325 
ii832 
1 5492 
i843g 
20976 

23238 
25298 
27203 
28983 


O. 


3o65g  3o822 


54129  54222 


54955  55o45  55i36 


55946 
56833 
57706 
58566 

59414 

60249 

61074 

6188 

62690 

63482 
64265 
65o38 
658o3 
66558 

67305 
68044 
68775 
69498 
70214 

70922 
71624 
72319 
7300-7 
73689 

74364 
75o33 
7569- 
76354 

770C:6 


32249 

33764 

35214 
366o6 
37947 

39243 
4o49' 
41713 
42895 
44o45 

45i66 
46260 
47329 
48374 
49396 

50398 
5i38i 
52345 
53292 


07071 
12247 
i58ii 
18708 

2I2l3 

23452 
25495 
27386 
29155 


G 


56o36 
56921 

57793 
58652 

59498 
60332 
61 1 56 
61968 
62769 

6356 

64343 

65ii5 

65879 

66633 

67380 
681 18 
68848 
69570 
70285 

70993 
71694 
72388 
73075 
73756 

7443i 

75  ICO 

75763 
76420 

77071 


32404 
33912 
35355 
36742 
38079 

39370 
40620 
4i833 
43oi2 
44i5g 

45277 
46368 
47434 
48477 
49497 

50498 
51478 
5244c 
53385 
543 14 

55227 
56i25 
57009 
57879 
58737 

59582 
6o4i5 
6123- 
62048 
62849 

63640 
64420 
65ig2 
65955 
66708 

67454 
681 91 
68920 
69642 
7o356 

71063 
71764 

7245' 

73i4- 
73824 

74498 
75i66 
75829 
76485 
771 36 


07746 
1 264g 
nil  25 
i8g74 
21448 

23664 
256t)o 
27568 
2g326 
30984 

3a558 
34o5g 
354g6 
36878 
38210 

39497 
40743 
41952 
43128 
44272 

45387 
46476 
47539 
48580 
49598 

50596 
5i575 
52536 
53479 
54406 


I 


08367 
I  3o3K 
16432 
■923:' 
21679 

23875 
25884 
2774g 
29496 
3ii45 

3271 1 
34205 
35637 
3701 4 
3834i 

39623 
40866 
42071 
43243 


553 1 7 
56214 
57096 
57966 
58822 

59666 
60498 
6i3ig 
6212g 
62929 

637 

64498 

65269 

66o3o 

66783 

67528 
68264 
68993 
69714 
70427 

71 1 33 
71833 
72526 
73212 
73892 

74565 
75233 
75895 
76551 


44385  44497 


45497 
46583 
47645 
48683 
49699 

50695 
51672 
5263i 
53572 
5^98 


55408 
563o3 
57184 
58o52 
58907 

59749 

6o58 

61400 

62209 

63oo8 

63797 
64576 
65345 
66106 
66858 

67602 
68337 
69065 
69785 


0894^ 
i34i6 
16733 
19494 
21909 

24o83 
26077 
27928 
29665 
3i3o5 

32863 
34351 

35777 
37148 
38471 

39749 
40988 
42190 
43359 


9 


45607 
46690 
47749 
4878; 


71204 
71903 
72595 
73280 
73959 

74632 
75299 
75gôi 
-76616 

7726(3 


5o7g4 
5176g 
52726 
53666 
54589 

554g8 
56391 
57271 
58i38 
58992 

59833 
6o663 
61482 
62290 
63087 

63875 
64653 
65422 
66182 
66933 

67676 
684ii 
69138 
69857 
70569 

71274 
71972 
72664 
73348 
74027 

74699 
75366 
76026 
76681 
7733o 


094s- 
13784 
1702g 
19748 

22l36 

242go 

26268 

2810 

2g833 

3i464 

33oi 

344g6 

35917 

37283 

386oi 

39875 
41110 
423o8 
43474 
44609 

45717 
46797 
47854 
48888 
49900 


5x865 
52820 
5375g 
54681 

55588 
5648o 
5735g 
58224 
59076 

59917 
60745 
61 563 
62370 
63i66 

63953 
64730 
65498 
(16257 
67007 

67750 


6g2io 
6gg29 
70640 

71 344 
72042 
72732 

73417 
74095 

74766 
75432 
760g  2 
76746 
773g5 


WUrn  tho  quantity  j:  wliose  root  is  to  I)c  found  consists 
of  sevL'ml  plact'ô  of  deciumls  anil  is  less  than  0,  ],  it 
will  1)0  convuniunt  to  lind  thfi  root  of  100:);  and  divide 
till;  result  by  10,  which  is  done  l)y  merely  changing  tho 
deciinjil  point  two  ligures  in  finding  lOOx,  and  one  tiguro 
in  dividing  by  tO. 


150 

15 
30 
45 
(10 
75 
90 
105 
131) 
135 


210 

205 

200 

195 

190 

185 

180 

175 

170 

165 

ice 

155 

21 

21 

20 

20 

19 

19 

18 

18 

17 

17 

10 

10 

42 

41 

411 

3il 

3h 

37 

30 

35 

34 

33 

32 

31 

u:t 

112 

CO 

511 

.57 

.51  i 

54 

.53 

51 

,50 

48 

47 

HI 

82 

8(1 

7,s 

70 

74 

72 

70 

(W 

Oli 

04 

02 

lll.S 

103 

mil 

98 

95 

93 

90 

88 

85 

83 

80 

78 

12li 

12:1 

120 

117 

in 

111 

los 

105 

102 

99 

90 

93 

117 

Ml 

1411 

137 

133 

130 

1211 

123 

no 

IK. 

112 

109 

IKS 

104 

11)0 

1.5li 

152 

14- 

141 

1411 

I3i; 

132 

12.^ 

121 

lo'J 

185 

180 

17li 

171 

107 

1U2 

156 

153 

149 

144 

14U 

1.13 

14B 

14-1 

142 

140 

138 

130 

134 

133 

130 

13? 

126 

15 

15 

14 

14 

14 

M 

14 

13 

13 

13 

13 

13 

30 

29 

29 

28 

28 

28 

27 

27 

20 

20 

20 

2.5 

44 

44 

43 

4:1 

42 

41 

41 

40 

40 

39 

;t8 

38 

59 

58 

.58 

.57 

.50 

.55 

54 

.54 

53 

.52 

51 

50 

74 

73 

72 

71 

70 

m 

08 

67 

Rfi 

05 

M 

63 

89 

88 

80 

8.5 

84 

83 

82 

HO 

79 

78 

77 

76 

104 

102 

101 

99 

98 

97 

95 

94 

92 

91 

90 

88 

118 

117 

115 

114 

112 

110 

109 

10- 

100 

104 

109 

101 

133 

131 

130 

128 

120 

124 

122 

121 

119 

117 

115 

113 

134 

12 
25 
37 

50 
62 
74 
87 
99 
112 


123 

122 

121 

120 

119 

118 

117 

iir 

115 

114 

113 

112 

111 

1 

12 

)2 

12 

12 

12 

12 

12 

12 

12 

II 

11 

II 

11 

2 

2.5 

24 

24 

24 

24 

21 

23 

2:1 

23 

23 

2:! 

22 

22 

3 

37 

37 

30 

30 

30 

35 

35 

35 

35 

31 

.34 

34 

.33 

4 

49 

49 

48 

48 

48 

47 

47 

40 

41, 

■II. 

45 

45 

44 

5 

62 

61 

01 

60 

60 

59 

59 

.58 

.58 

57 

57 

50 

.56 

0 

74 

V3 

73 

72 

71 

71 

70 

70 

09 

08 

l»i 

67 

67 

'/ 

80 

85 

85 

84 

83 

83 

82 

81 

81 

80 

79 

78 

78 

8 

98 

98 

97 

90 

95 

94 

94 

93 

92 

91 

90 

90 

89 

9 

111 

110 

lOU 

108 

107 

106 

105 

104 

104 

103 

102 

101 

100 

110 

109 

108 

107 

too 

105 

104 

103 

102 

101 

100 

99 

98 

11 

11 

11 

11 

11 

11 

III 

III 

10 

10 

10 

10 

10 

22 

0.-) 

22 

21 

21 

21 

21 

21 

20 

20 

20 

90 

20 

33 

33 

32 

32 

32 

32 

31 

31 

31 

30 

30 

30 

29 

44 

44 

43 

43 

42 

42 

42 

41 

41 

40 

40 

40 

39 

55 

55 

.54 

.54 

.53 

53 

.52 

.52 

51 

51 

.50 

.50 

49 

00 

65 

65 

64 

64 

63 

62 

62 

61 

01 

60 

.59 

59 

77 

70 

76 

75 

74 

74 

73 

72 

71 

71 

70 

69 

69 

88 

87 

80 

81; 

85 

84 

83 

82 

82 

81 

80 

79 

78 

99 

98 

97 

90 

95 

95 

94 

93 

92 

91 

90 

89 

88 

96 

95 

94 

93 

92 

91 

90 

89 

88 

87 

ec 

85 

34 

83 

82 

81 

10 

10 

(I 

9 

9 

!l 

9 

0 

0 

9 

fi 

9 

8 

8 

8 

R 

19 

19 

19 

19 

18 

Is 

IS 

Is 

Is 

17 

r, 

n 

17 

17 

16 

l(i 

29 

•29 

•28 

28 

■2- 

27 

•Si 

■j- 

2i. 

2t 

21: 

20 

'-Î.5 

25 

25 

94 

38 

38 

38 

37 

37 

36 

30 

36 

35 

35 

3  1 

34 

3-1 

33 

33 

:« 

48 

48 

47 

47 

40 

46 

1.-, 

15  1-1 

41 

4:1 

■13 

-!■' 

4^' 

41 

41 

58 

.57 

56 

56 

.55 

55 

.51 

5.'. 

53 

.52 

.52 

51 

51) 

,511 

49 

49 

ta 

67 

liO 

65 

64 

64 

63 

62 

62 

61 

60 

60 

.59 

5S 

.57 

77 

7li 

75 

74 

74 

73 

72 

71 

70 

70 

69 

lï< 

67 

60 

66 

65 

86 

86 

85 

M 

83 

82 

81 

SO 

79 

78 

"7 

77 

70 

75 

74 

73 

73 


72 


TABLE  I.— OF  SQUARE  ROOTS. 

Tlie  proposed  number  is  to  he  fourni,  as  for  as  the   second   decimal   place,  in  the  side  column  of  the  table,  and  the    third 
decimal  at  the  top  of  one  of  (he  vertical  columns;   the  number  coi-responiliny;  is  the  re([uircd  root. 


0.60 
o.Ci 
0.62 
0.63 
0.64 

0.65 
0.66 
0.67 
0.68 
0.69 

0.70 
0.71 
0.73 
0.73 


7/4 


0.75 

0.76 

0.77 
0.7S 

0.79 

0.80 
0.81 

0.S2 
0.83 
0.84 

0.85 
0.86 
0.87 
0.88 
0.89 

0.90 

O.yl 
0.92 
0.93 
0.94 

eg*; 
0.96 
0.97 
0.98 
0-99 

1. 00 

1 .01 
1.03 

i.o3 
1.04 

i.o5 
1.06 
1.07 
1.08 
1.09 

I. in 
I.I  I 
I.I  2 

I.i3 

1. 14 

i.i5 
i.iG 

1. 17 

1. 18 
1,19 


0 


0.77460 
0.7SIO3 

0.78740 
0.79373 

0.80000 

0.80623 
0.81240 

0.81854 

0.S2462 
o.83o66 

0.83666 


0.84853 
0.85440 
0.86023 

o.866o3 
0.87178 
0.87750 
o.883i8 
0.88882 

0.89443 
0.90000 
o.go554 
0.91 1  o4 
o.gi652 

0.92195 
0.92736 
0.93274 
0.93S08 
0.94340 


0.95394 
0.95917 
0.96437 
0.96954 

0.97468 
0.97980 
0.98489 
0.98995 
0.99499 

1 .00000 
I  .oo4g9 
I  .ooggS 
1. 01 489 
1 .01 980 

I .02470 
1.02956 
i.o344i 
I .03923 
I .o44o3 

I. 04881 
1.05357 
I .o583o 
I .o63oi 
I. 06771 

1.07238 
1.07703 
I .08167 
I .08628 
1 .09087 

0 


1 


77524 
78166 
78804 

79436 
80062 

80685 
8i3o2 
8igi5 
82523 
83i26 

83726 
84321 
84912 
85499 
86081 

86660 
87235 
S7807 
88374 
88938 


90056 
90609 

91 1 59 
9170b 

gasSo 

92790 
93327 
93862 
94393 

94921 
95446 

95969 
96488 
97005 

97519 
98031 
9853g 
99045 
99549 

ooo5o 
00549 
01045 
01 538 
02029 

025i8 
o3oo5 
03489 
03971 

o445i 

04929 
o54o4 
05877 
o6348 
06818 

07285 
07750 
08213 
08674 
091 33 

] 


2 

3 

4 

5 

6 

7 

8 

9 

77589 

77653 

77717 

77782 

77846 

77910 

77974 

78038 

78230 

78294 

78358 

78422 

78486 

78549 

78613 

78677 

78867 

78930 

78994 

79057 

79120 

79183 

79246 

79310 

79498 

79561 

79624 

79687 

79750 

79812 

79875 

79937 

80125 

80187 

8o25o 

8o3i2 

80374 

8o436 

80498 

8o56i 

80747 

80808 

80870 

80932 

80994 

8io56 

81117 

81179 

81 363 

81425 

81486 

81548 

81609 

81670 

81731 

81792 

8ig76 

82037 

82098 

82i58 

82219 

82280 

82341 

82401 

82583 

82644 

82704 

82765 

82825 

82885 

82g46 

83oo6 

83x87 

83247 

833o7 

83367 

83427 

83487 

83546 

836o6 

83785 

83845 

83905 

83g64 

84024 

84o83 

84i43 

84202 

8438o 

84439 

84499 

84558 

84617 

846-76 

84735 

84794 

84071 

85o29 

85ob8 

85i47 

852o6 

85264 

85323 

85381 

85557 

856i5 

85674 

85732 

85790 

8584g 

85907 

85965 

86139 

86197 

86255 

863 1 3 

86371 

86429 

86487 

86545 

86718 

86776 

86833 

86891 

86q48 

87006 

87063 

87121 

87293 

87350 

87407 

87464 

87521 

8757g 

87636 

87693 

87864 

87920 

87g77 

88034 

88091 

88148 

88204 

88201 

88431 

88487 

88544 

88600 

88657 

88713 

8876g 

88826 

88994 

89051 

89107 

89163 

89219 

89275 

8g33i 

89387 

89554 

89610 

89666 

89722 

89778 

8g833 

89889 

8gg44 

goi  1 1 

90167 

90222 

90277 

90333 

9o388 

90443 

9049g 

90664 

90719 

90774 

go83o 

go885 

90940 

90995 

9'  049 

91214 

91269 

91324 

91378 

91433 

91488 

91 542 

9' 597 

91761 

gi8i5 

91869 

91924 

91978 

92033 

92087 

92141 

92304 

92358 

92412 

92466 

92520 

92574 

92628 

92682 

92844 

92898 

92952 

g3oo5 

93o5g 

93ii3 

93167 

g3220 

93381 

93434 

93488 

g354i 

93595 

g3648 

93702 

g3755 

93915 

93968 

94021 

94074 

94128 

94181 

94234 

94287 

94446 

94499 

94552 

g46o4 

94657 

94710 

94763 

9481 5 

94974 

95026 

9507g 

95i3i 

g5i84 

95237 

95289 

95341 

95499 

95551 

95603 

95656 

95708 

95760 

95812 

95864 

96021 

96073 

96125 

96177 

96229 

g628i 

96333 

96385 

96540 

96592 

96644 

96695 

96747 

96799 

96850 

96902 

97057 

97108 

97160 

97211 

97263 

97314 

97365 

97417 

97570 

97622 

97673 

97724 

97775 

g7826 

97877 

97929 

98082 

98133 

98184 

9S234 

g8285 

g8336 

983S7 

98438 

98590 

98641 

986gi 

98742 

98793 

98843 

98S94 

98944 

99096 

99146 

99197 

99=47 

99298 

99348 

99398 

99448 

99599 

99649 

99700 

99750 

99800 

99860 

99900 

99950 

001 00 

001 5o 

00200 

002  5o 

oo3oo 

oo34g 

oo3gg 

00449 

ooSgS 

00648 

00698 

00747 

00797 

00846 

oo8g6 

oog46 

oiog4 

01143 

oiig3 

01242 

01292 

01 341 

01390 

oi44o 

01 587 

01637 

01686 

01735 

01784 

01 833 

01882 

oig3i 

02078 

02127 

02176 

02225 

02274 

02323 

02372 

02421 

02567 

02616 

02665 

02713 

02762 

0281 1 

02859 

02908 

o3o53 

03l02 

o3i5o 

o3i99 

o3247 

03296 

03344 

03392 

03537 

03586 

03634 

o3682 

o373o 

03779 

08827 

03875 

04019 

04067 

o4ii5 

o4i63 

04211 

042  5g 

o43o7 

04355 

04499 

04547 

o45g4 

04642 

04690 

04738 

04785 

04833 

04976 

o5o24 

o5o7i 

o5ii9 

05167 

o52i4 

05262 

o53o9 

o545i 

0549g 

o5546 

o55q4 

o564i 

o5688 

o5736 

05783 

o5g25 

o5g72 

0601  g 

06066 

061 1 3 

06160 

06207 

06254 

o63q5 

06442 

06489 

06536 

06583 

o663o 

06677 

06724 

06864 

0691 1 

06958 

07005 

07o5i 

07098 

07145 

07191 

07331 

07378 

07424 

07471 

07517 

07564 

07610 

07667 

07796 

07842 

078S9 

07935 

07981 

08028 

08074 

08120 

08259 

o83o5 

o835i 

08397 

08444 

08490 

o8536 

08582 

08720 

08766 

08812 

08858 

08904 

08950 

08995 

09041 

09179 

09225 

09270 

09316 

09362 

09407 

09453 

09499 

2 

3 

4 

5 

6 

7 

8 

9 

65 

64 

7 

6 

i3 

i3 

20 

IQ 

26 

2h 

33 

32 

3q 

38 

46 

45 

52 

5i 

59 

58 

63 

6 
i3 
19 

25 
32 

38 
44 
5o 
57 


59 

58 

6 

6 

12 

12 

18 

17 

24 

23 

3o 

2Q 

35 

35 

4i 

4i 

47 

46 

53 

52 

6 
II 

17 

23 

29 
34 
4o 
46 
5i 


53 

52 

5 

5 

II 

10 

16 

16 

21 

21 

27 

26 

32 

3i 

37 

36 

42 

42 

48 

47 

5 
10 
i5 
20 
26 
3i 
36 
4i 
46 


47 

46 

5 

5 

9 

9 

14 

i4 

IQ 

18 

24 

23 

28 

28 

33 

32 

38 

37 

42 

4i 

62 

61 

6 

6 

12 

12 

19 

18 

23 

24 

3i 

3i 

37 

37 

43 

4J 

5o 

49 

56 

55 

60 


55154 

6  5 
II  II 

17'  16 

22!  22 
28  27 
33i32 

39  [38 
44  43 
49I49 


5o 

49 

5 

5 

10 

10 

i5 

i5 

20 

30 

25 

25 

3o 

29 

35 

34 

40 

39 

45 

44 

48 

5 

10 
i4 
19 
34 

?9 
34 
38 
43 


TABLE  I.  — OF  SQUARE  ROOTS. 

The  proposed  number  \s  to  be  fourni,  as  f.\r  as  the  second  decimal  place,  in    tiie  siilc   column  of  the   table,  and  the   third 
(lecimoi  at  the  top  of  one  of  the  vortical  coluuuis  ;  the  number  cor  respond  iu;i;-  is  tlio  required  root. 


0 

1 

■2 

3 

4 

5 

6 

7 

S 

9 

I.2tl 

1.09544 

09590 

09636 

og68i 

09727 

09772 

09818 

09864 

09909 

09955 

46 

45 

1.31 

r.  10000 

10045 

loogi 

101 36 

10182 

10327 

10272 

io3i8 

io363 

io4o8 



— 

1. 22 

1. 1 0454 

10499 

10544 

10589 

io635 

10680 

10725 

10770 

10816 

10860 

I 

6 

5 

1.53 

I.KK)o5 

I  ogSo 

10995 

no4i 

1 1 086 

ui3i 

U176 

11221 

11265 

11810 

2 

9 

9 

1-24 

I.I  j355 

1 1 400 

11445 

ii4go 

11 535 

ii58o 

11624 

ii66g 

11714 

1176g 

3 
4 

M 
18 

i4 
18 

1.23 

1.11S03 

11848 

Ii8g3 

iiq37 

11982 

12027 

1 2071 

121 16 

1 2161 

I2305 

5 

28 

23 

1.26 

I.I2250 

12294 

I233q 

12383 

12428 

13472 

125l7 

I256i 

1 3606 

13660 

6 

28 

27 

1.27 

1. 1  2694 

12739 

12783 

12827 

12872 

12916 

12960 

i3oo4 

i3o4g 

i3og3 

7 

82 

82 

1.28 

I..3I37 

i3i8i 

l3225 

13270 

i33i4 

13358 

1 3402 

1 3446 

13490 

13634 

8 

37 

36 

1.30 

1. 1 3578 

1 3622 

i3666 

1 3710 

13754 

13798 

i3842 

1 3886 

18930 

i3g74 

9 

4i 

4i 

i.3o 

1.14018 

1 4061 

i4io5 

i4i4g 

14193 

14237 

14280 

14324 

1 4368 

i44i3 

i.3i 

1. 14455 

14499 

14543 

14586 

i463o 

14673 

14717 

1 4761 

i48o4 

14848 

1.32 

1.14891 

14935 

14978 

l5022 

i5o65 

i5io9 

i5i52 

15195 

i523g 

16282 

1.33 

I.I  5326 

15369 

1 541 2 

1 5456 

15499 

i5542 

15585 

16629 

16672 

1571 5 

44 

43 

1.34 

I.I5758 

i5So2 

1 5845 

1 5888 

i5g3i 

15974 

16017 

16060 

i6io3 

16146 

I 
2 

4 

4 
9 

1.35 

i.i6igo 

16233 

16276 

i63ig 

16362 

i64o4 

16447 

16490 

1 6533 

16676 

1.36 

1.16619 

16662 

16705 

16748 

16790 

16833 

16876 

16919 

16962 

17004 

3 

i3 

i3 

1.37 

1.17047 

17090 

17132 

17175 

17218 

17260 

i73o3 

17346 

17388 

17481 

4 

18 

17 

1.38 

1. 1 7473 

17516 

17558 

1 7601 

17644 

1-686 

17739 

17771 

17813 

17866 

5 

22 

22 

1-39 

I. .7898 

1 7941 

17983 

18025 

18068 

18110 

18162 

18196 

18237 

1827g 

6 

26 
3i 

26 
80 

1.40 

I.I8322 

1 8364 

i84o6 

18448 

i84gi 

18533 

18575 

18617 

18669 

18701 

7 

8 

85 

84 

1.41 

1. 18743 

18786 

18828 

18870 

18912 

i8q54 

18996 

igo38 

19080 

19122 

9 

40 

39 

1.42 

1 . 1 91 64 

19206 

19248 

19290 

19331 

19373 

19415 

19457 

19409 

19541 

1.43 

1. 1 9583 

19624 

19666 

19708 

19750 

1 9791 

ig833 

19875 

1 991 7 

19958 

1.44 

1.20000 

20042 

20o83 

20125 

20167 

20208 

20230 

20291 

20333 

20374 

1.45 

i.2o4i6 

20457 

2049g 

2o54o 

20582 

20623 

20665 

20706 

20748 

2078g 

42 

4i 

1.46 

i.2o83o 

308 -73 

2ogi3 

2og55 

20996 

21037 

31078 

31120 

21161 

21 203 

— 

— 

1.4- 

I. 21 244 

21285 

21326 

21367 

21408 

2i45o 

21491 

2l632 

21673 

21614 

I 

4 

4 

1.4s 

I. 21655 

21696 

21737 

21778 

21820 

21861 

21902 

2ig43 

21984 

22025 

3 

8 

8 

1.49 

1 .22066 

22107 

23147 

22188 

2222g 

22370 

223ll 

32352 

22393 

22434 

8 
4 
5 

i3 

12 
16 
31 

i.5o 

1.224-4 

225l5 

22556 

225g7 

22638 

22678 

22719 

22760 

23801 

33841 

17 
21 

i.5i 

1.228S2 

23933 

22g63 

23oo4 

23o45 

23o85 

23l26 

23167 

28207 

28248 

6 

25 

35 

1.52 

1.23288 

23339 

2336g 

23410 

23450 

23491 

2353i 

23572 

28612 

33653 

7 

29 

29 

1.53 

1.23693 

33734 

23774 

238i4 

23855 

23895 

2  3g35 

23g76 

24016 

24o56 

8 

34 

33 

1.54 

1.24097 

24137 

24177 

24218 

24258 

24298 

24338 

24378 

24418 

3445g 

9 

38 

37 

1.55 

1.24499 

24539 

2457g 

2461  g 

24660 

24700 

24740 

24780 

24820 

24860 

1.56 

1.24900 

24940 

24g8o 

25020 

25o6o 

25lOO 

35i4o 

25i8o 

26330 

36260 

1.57 

i.253oo 

25340 

2537g 

254ig 

2545g 

25499 

35539 

25579 

36618 

26668 

1.58 

1.25698 

25738 

25778 

25817 

25857 

25897 

35g36 

26976 

2601 6 

26066 

4o 

39 

1-59 

1.26095 

26135 

26174 

26214 

26254 

26293 

26333 

26373 

26412 

26452 

I 
2 

4 
8 

4 
8 

1.60 

i.264oi 

26531 

26570 

26610 

3664g 

26689 

26728 

26768 

26807 

26846 

1. 61 

1.26886 

26925 

26964 

27004 

27043 

27083 

27122 

27161 

27201 

27240 

3 

12 

13 

1.62 

1.2727g 

27318 

27358 

27397 

27436 

27475 

275i5 

27554 

27698 

27682 

4 

t6 

16 

1.63 

1.27671 

27711 

27750 

27789 

2-828 

27867 

27906 

27945 

37984 

28028 

5 

20 

20 

1.64 

1.28062 

28102 

a8i4i 

28180 

2821g 

28258 

28297 

38335 

28874 

28418 

6 

24 
28 

32 

23 

1.65 

1.28453 

28491 

28530 

28569 

28608 

28647 

28686 

28726 

28768 

28802 

7 
8 

27 
3i 

1.66 

1.2S841 

28880 

28919 

28957 

28996 

29035 

29074 

29112 

29161 

29190 

9 

36 

85 

1.67 

1.29228 

29267 

29306 

29345 

29383 

29422 

29460 

29499 

2g538 

29676 

1.68 

I. 2961 5 

29653 

29692 

29730 

2976g 

29808 

39846 

29886 

2g923 

29962 

1.69 

i.3oooo 

3oo38 

30077 

3oii5 

3oi54 

30192 

3o23i 

3o36g 

8o3o7 

8o346 

1.70 

i.3o384 

3o422 

3o46i 

3o499 

3o537 

30576 

3o6i4 

3o652 

80690 

80729 

88 

37 

1.71 

I .30767 

3o8o5 

3o843 

30882 

30920 

30958 

30996 

3io34 

81072 

3iiii 

1.72 

i.3ii49 

31187 

3l225 

3i  263 

3i3oi 

3i33g 

3i377 

3i4i5 

81453 

^'f9' 

I 

4 

4 

1.73 

i.3i529 

3i567 

3i6o5 

3i643 

3i68i 

31719 

31757 

31796 

3i833 

81871 

2 

8 

7 

1.74 

1 -31909 

31947 

31985 

32033 

32061 

32098 

32136 

32174 

82212 

32260 

3 

11 
i5 
19 

23 

II 

1.75 

1.32288 

32325 

32363 

83401 

32439 

32476 

325i4 

32552 

32690 

82627 

4 
5 

i5 

19 
22 

1.76 

1.32665 

32703 

32740 

32778 

32816 

33853 

32891 

33939 

82966 

83oo4 

6 

1-77 

i.33o4i 

330-9 

33ii6 

33i54 

33192 

33229 

33267 

333o4 

83342 

33379 

7 

27 

26 

I. -8 

1. 3341 7 

33454 

33492 

33529 

33566 

336o4 

33641 

336-9 

88716 

33764 

8 

3o 

80 

'•"9 

1. 33791 

33828 

33866 

33903 

33940 

33978 

3401 5 

34062 

84090 

34127 

9 

34 

83 

0 

1 

-2 

•3 

4 

ij 

6 

7 

,c.' 

9 

TABLE  I.— OF  SQUARE  ROOTS. 

The  proposed  number  is  to  be  found,  as  far  as  the  second  decimal   place,  in   the  side  column  of  the  table,  and  the  third 
decimal  at  the  top  of  one  of  the  vertical  columns  ;  the  number  correspoudinf;  is  the  required  root. 


0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

1.80 

1.34:64 

34201 

34239 

34276 

343:3 

34350 

34387 

34435 

34462 

34499 

38 

1. 81 

1.34536 

34573 

34611 

34648 

34685 

34722 

34759 

34796 

34833 

34870 

— 

1.82 

1.34907 

34944 

34981 

35019 

35o56 

35093 

35: 3o 

35167 

35204 

3524: 

I 

4 

1.83 

1.35277 

353i4 

3535i 

35388 

35425 

35462 

354gg 

35536 

35573 

356io 

2 

8 

1.84 

1.35647 

35683 

35720 

35757 

35794 

3583i 

35868 

35904 

35941 

35978 

3 
4 
5 

i: 
i5 

1.85 

i.36oi5 

36o5i 

36o88 

36:25 

36:62 

36198 

36235 

36272 

363o8 

36345 

19 

1.86 

1.36382 

364i8 

36455 

364g2 

36528 

36565 

36602 

36638 

36675 

367:1 

6 

23 

1.87 

1.36748 

36785 

36821 

36858 

368g4 

36931 

36g67 

37004 

37040 

37077 

7 

27 

1.88 

1. 371 1 3 

371 5o 

37186 

37222 

37259 

37295 

37332 

37368 

374o5 

3744: 

8 

l"                         1 

37 

1.89 

1.37477 

37514 

37550 

37586 

37623 

37659 

37695 

37732 

37768 

37804 

9 

34 

1.90 

1.37840 

37877 

37913 

37949 

37985 

38022 

38o58 

38094 

38: 3o 

38:67 

: 

4 

i.gi 

I.38203 

38239 

38275 

383: 1 

38347 

38384 

38420 

38456 

384g2 

38528 

2 
3 
4 
5 
6 

7 

1.02 

1.38564 

38600 

38636 

38672 

38708 

38744 

38780 

388:6 

38852 

38888 

II 

i5 

1.93 

1.38924 

38960 

38996 

39032 

39068 

3g:o4 

3gi4o 

39:76 

3g3i2 

39248 

1.94 

1.39284 

39330 

39356 

3g3g2 

39427 

39463 

39499 

39535 

3957: 

39607 

'9 
22 

1.95 

1.39642 

39678 

39714 

39750 

39786 

39821 

39857 

3g8g3 

39929 

3gg64 

7 
g 

26 
3o 

1.96 

1 .40000 

4oo36 

40071 

40:07 

40143 

40:78 

402:4 

402  So 

40385 

4o32i 

33 

1.97 

1.40357 

40392 

40428 

40464 

4o4gg 

4o535 

4o57o 

40606 

4o64: 

40677 

36              y 

1.98 

I. 4071 2 

40748 

40784 

40819 

4o855 

40890 

40936 

4og6; 

40996 

4:o32 

— 

1-99 

I. 41067 

4iio3 

4n38 

4::  74 

4:209 

4:244 

4:280 

41 3: 5 

4:35: 

4:386 

I 

4 

2.00 

1.41431 

41457 

41492 

4:527 

4:563 

4:598 

4:633 

41669 

4:704 

4:739 

2 
3 

7 
1: 

2.01 

1. 41774 

4i8io 

4:845 

41880 

4:9:5 

4:g5: 

4: 986 

42021 

43o56 

42og2 

4 

i4 

2.02 

1. 421 27 

42162 

42197 

43233 

42267 

42302 

42338 

43373 

42408 

42443 

5 

18 

2.o3 

1.42478 

425i3 

42548 

42583 

436:8 

42653 

42688 

42724 

42759 

42794 

6 

22 

2.o4 

1.42839 

42864 

42899 

43934 

42969 

43oo3 

43o38 

43073 

43: 08 

43:43 

7 
8 

25 

2.o5 

1.43178 

43213 

43348 

43283 

433:8 

43353 

43388 

43422 

43457 

43492 

9 

=9 

32 

35 

2.06 

1.43527 

43563 

43597 

4363: 

43666 

43701 

43786 

4377: 

438o5 

43840 

4 

2.07 

1.43S75 

43gio 

43944 

43979 

4401 4 

44o4g 

44o83 

44:  :  8 

44:53 

44:87 

1 

2.08 

1.44222 

44357 

4429: 

44326 

4436: 

44895 

44430 

44465 

44499 

44534 

2 
3 
4 

7 

2.09 

1.44568 

446o3 

44637 

44672 

44707 

44741 

44776 

44810 

44845 

44879 

:  I 
i4 

2.10 

I. 4491 4 

44948 

44983 

450:7 

45o52 

45o86 

45:2: 

45:55 

45:90 

45224 

5 
6 

18 

2. II 

1.45258 

45293 

45327 

45362 

45396 

45430 

45465 

45499 

45534 

45568 

21 
25 

28 

32 

2.12 

I .45602 

45637 

4567: 

45705 

4573g 

45774 

45808 

45843 

45877 

45gi: 

7 
8 

2.l3 

1.45945 

45979 

460:4 

46o48 

46082 

461:6 

46:5: 

46:85 

462:9 

46253 

2.l4 

1.46287 

46322 

46356 

46390 

46434 

46458 

46492 

46536 

4656: 

46595 

34            y 

2.l5 

1 .46639 

46663 

46697 

4673: 

46765 

467gg 

46833 

46867 

4690: 

46935 

I 

3 

3.16 

1 .46969 

47003 

47037 

47071 

47:05 

47:39 

47173 

47207 

4724: 

47275 

2 

7 

2.17 

I .47309 

47343 

47377 

474:: 

47445 

47479 

475i3 

47547 

47580 

476:4 

3 

:o 

2.18 

1 .47648 

47682 

477:6 

47750 

47784 

478:7 

4785: 

47885 

479' 9 

47953 

4 

:4 

2.19 

1.47986 

48020 

48o54 

48088 

48122 

48:55 

48189 

48223 

48257 

48290 

5 
6 

7 

17 

2.20 

I.4S324 

48358 

4839: 

48425 

48459 

48492 

48526 

48560 

48593 

48627 

20 

24 

2.21 

I. 48661 

48694 

48728 

48762 

487g5 

4882g 

48862 

48896 

48y3o 

48963 

8 

27 

33 

2.22 

1 .48997 

49o3o 

49064 

49097 

4g:3: 

4g:64 

49:98 

4g23: 

49265 

49298 

9 

3: 

2.23 

1 .4g332 

49365 

493g9 

49432 

4g466 

4g499 

49533 

49566 

49599 

49633 

3 

7 

2.24 

1 .49666 

49700 

49733 

49766 

4g8oo 

49833 

49867 

49900 

49933 

4gg67 

I 

2 

2.25 

i.Soooo 

5oo33 

50067 

5oioo 

5oi33 

50167 

50200 

5o233 

50266 

5o3oo 

3 

10 
i3 

2.26 

i.5o333 

5o366 

5o399 

5o433 

5o466 

5o499 

5o532 

5o566 

5o5g9 

5o632 

4 
5 
6 

2.27 

i.5o665 

50698 

50733 

50765 

50798 

5o83: 

5o864 

50897 

50930 

5og64 

17 

2.28 

1.50997 

5io3o 

5:o63 

51096 

5::  29 

5i:63 

5:195 

5:228 

51261 

5:294 

20 

23 

26 

2.29 

i.5i327 

5i36o 

5:394 

5:427 

5: 460 

5:493 

5:526 

5:559 

5:592 

5:625 

7 
8 

2.3o 

i.5i658 

51690 

5:723 

5:756 

5:78g 

5:832 

5i855 

5:888 

51921 

5:954 

32         9 

3o 

2.3l 

1.51987 

5303O 

53o53 

53o85 

52:18 

52:5: 

52:84 

533:7 

5225o 

52283 

— 

2.32 

i.523i5 

52348 

5238: 

534:4 

52447 

53480 

525:2 

53545 

53578 

526:1 

I 

3 

2.33 

1.52643 

53676 

52709 

52742 

52774 

52807 

52840 

52872 

53go5 

52938 

2 

6 

2.34 

I. 52971 

53oo3 

53o36 

53069 

53ioi 

53:34 

53:67 

5319g 

53232 

53264 

3 
4 
5 

:o 
i3 

2.35 

1.53397 

53330 

53362 

53395 

53428 

53460 

53493 

53525 

53558 

53590 

:6 

2.36 

1.53623 

53655 

53688 

5372: 

53753 

53786 

538:8 

5385: 

53883 

^^/J'.^ 

6 

19 

2.37 

1.53948 

53981 

540: 3 

54045 

54078 

54: 10 

54:43 

54:75 

54208 

54340 

n 

22 

2.38 

1.54272 

543o5 

54337 

54370 

54402 

54434 

54467 

544g9 

54532 

54564 

8 

26 

2.39 

1.54596 

5463g 

54661 

54693 

54726 

54758 

54790 

54822 

54855 

54887 

9 

29 

0 

1 

2 

3 

4 

5 

6 

7 

R 

9 

_ 

TABLE  I.  — OF  SQUARE  ROOTS. 


Tlie 

proposed 

numbe 

■  is  to  bi 

found. 

as  lar  as  the  second  t 

eciiiKil 

])Uice,  in  the  sii 

e  column  of  the  table,  and  the  third 

ilcciim 

I  at  llie  top  of  one  of  the  vertical  ooluniiis;  the  luiniber  con-e^pondins  is  t!ie  rc()uiro(l  root. 

0 

1 

0 

3 

1 

5 

6 

7 

8 

y 

a.4o 

I. 54919 

54952 

54984 

55oi6 

55o48 

55o8i 

55ii3 

55i45 

55177 

55310 

33 

2.41 

1.55242 

55274 

553o6 

55338 

55371 

554o3 

55435 

55467 

55499 

55531 

__ 

2.42 

1.55563 

55596 

5562S 

55660 

55692 

55734 

55756 

55788 

55820 

55853 

, 

3 

2.43 

I .55885 

55917 

55949 

55981 

56oi3 

56o45 

56077 

56109 

56i4i 

56173 

2 

7 

2.44 

I. 50205 

56237 

562(i9 

56301 

56333 

56365 

56397 

56429 

5646i 

56493 

3 
4 
5 

10 
i3 

17 

2.45 

1.56525 

56557 

56589 

56621 

56652 

56684 

56716 

56748 

56780 

56812 

2.46 

1.56844 

56876 

56908 

56939 

56971 

57003 

57035 

57067 

57000 

57i3i 

6 

30 

2.47 

I. 57162 

57194 

57226 

57258 

57290 

57321 

57353 

57385 

574/7 

57448 

7 

23 

2.48 

1.57480 

5-5i2 

57544 

57575 

57607 

57639 

57671 

57702 

57734 

57766 

8 

26 

2.49 

1-57797 

57829 

57861 

57892 

57924 

57956 

57987 

58019 

58o5i 

58082 

9 

3o 

2.5o 

i.58ii4 

58i46 

58177 

58209 

58240 

58272 

583o4 

58335 

58367 

583g8 

32 

2.5[ 

I.58430 

5846i 

58493 

58524 

58556 

58588 

58619 

5865i 

58682 

58714 

I 

3 

2.52 

1.58745 

58777 

588o8 

5884o 

58871 

58902 

58934 

58g65 

589g7 

59028 

3 

6 

2.53 

1.59060 

59091 

59123 

59154 

59185 

59217 

59248 

59280 

59311 

59342 

3 

10 

2.54 

1.59374 

59405 

59437 

59468 

59499 

59531 

59562 

59593 

59625 

59656 

4 

i3 

2.55 

1.59687 

59719 

59750 

59781 

59812 

59844 

59875 

59906 

59937 

59969 

5 
6 

16 
19 

22 

2.56 

1.60000 

6oo3i 

60065 

60094 

60125 

6o!56 

60187 

60319 

6o25o 

60281 

7 
8 

2.57 

i.6o3i2 

60343 

60375 

6o4o6 

60437 

60468 

60499 

6o53o 

6o562 

60593 

26 

2.58 

1 .60624 

60655 

60686 

60717 

60748 

60779 

60810 

60842 

60873 

6ogo4 

9 

29 

2.59 

1 .60935 

60966 

60997 

61028 

61059 

61&90 

61121 

61 1  53 

611 83 

61214 

2.60 

1. 61 245 

61276 

6i3o7 

61 338 

61369 

6i4oo 

6i43i 

61463 

61493 

61  524 

01 

2.61 

1. 61 555 

61 586 

61617 

61648 

61679 

61710 

61741 

61771 

61803 

61833 

1 

3 

2.62 

1.61864 

61895 

61926 

61957 

61988 

62019 

62049 

62080 

631 11 

63142 

3 

6 

2.63 

1. 621 73 

62204 

62234 

62265 

63396 

62327 

62358 

62388 

63419 

62450 

3 

9 
12 

2.64 

1.624S1 

62512 

62542 

62573 

62604 

63635 

62665 

62696 

62727 

62757 

4 

2.65 

1.62788 

62819 

62850 

62880 

6291 1 

62942 

62972 

63oo3 

63o34 

63o64 

5 
6 

16 

19 
22 

2.66 

1.63095 

63126 

63i56 

63187 

63218 

63248 

63379 

63310 

63340 

63371 

7 

2.67 

I.6340I 

63432 

63463 

63493 

63524 

63554 

63585 

636i5 

63646 

63677 

8 

25 

2.68 

I .63707 

63738 

63768 

63799 

63839 

63860 

63890 

63921 

63951 

63g82 

9 

38 

2.69 

1 .64oi  2 

64043 

64073 

64io4 

64i34 

64i65 

64195 

64335 

64256 

64286 

3o 

2.-0 

1.64317 

64347 

64378 

64408 

64438 

64469 

64499 

64530 

6456o 

645go 

2.71 

1. 64621 

6465i 

64682 

64713 

64742 

64773 

648o3 

64833 

64864 

648g4 

I 

3 

2.72 

1 .64924 

64955 

64985 

65oi5 

65o45 

65076 

65 1 06 

65i36 

65i67 

65 197 

2 

6 

2.-3 

1.65227 

65237 

65288 

653i8 

65348 

65378 

65409 

65439 

65469 

65499 

3 

9 

2.74 

1.65529 

6556o 

655go 

65620 

6565o 

6568o 

6571 1 

65741 

65771 

658oi 

4 

r 

12 
i5 
18 

2.75 

1.65831 

6586i 

65892 

65922 

65952 

65982 

6601 3 

66043 

66072 

66103 

6 

2.76 

1.66:32 

66163 

66193 

66233 

66353 

66383 

663i3 

66343 

66373 

664o3 

7 

21 

2-77 

1.66433 

66463 

66493 

66523 

66553 

66583 

6661 3 

66643 

66673 

66703 

8 

24 

2.78 

1.66733 

66763 

66793 

66823 

66853 

66883 

66913 

66943 

66973 

67003 

9 

27 

2.7g 

1.67033 

67063 

67093 

67123 

67153 

67183 

67212 

67242 

67272 

67302 

29 

2.80 

1.67332 

67362 

67392 

67422 

67451 

67481 

67511 

67541 

67571 

67601 

I 

3 

2.81 

1.67631 

67660 

67720 

67750 

67780 

67809 

67839 

67869 

67899 

2 

6 

2.82 

1 .67929 

6-958 

6798S 

68018 

68048 

68077 

68107 

68137 

68167 

68196 

3 

9 

2.83 

1.68226 

68b  56 

68385 

683i5 

68345 

68375 

684o4 

68434 

68464 

68493 

4 

5 

2.84 

1.68523 

68553 

68582 

68612 

68642 

68671 

68701 

68731 

68760 

68790 

11 

2.85 

t. 6881 9 

68849 

68879 

68908 

68938 

68967 

68997 

69027 

6go56 

6go86 

6 

7 
8 

17 
20 

2.86 

1.691 1 5 

69145 

69174 

69204 

69234 

69363 

69293 

6g322 

6g352 

69881 

23 

2. 87 

I  .f)94i  I 

6g44o 

69470 

69499 

69529 

69558 

69588 

69617 

69647 

69676 

9 

26 

2.88 

1 .69706 

69735 

69765 

69794 

69823 

69853 

69882 

69912 

69941 

69871 

2.Sy 

1.70000 

70029 

70059 

70088 

701 1 8 

70147 

70176 

70206 

70235 

70265 

28 

2.90 

1.70294 

7o323 

70353 

7o382 

70411 

70441 

70470 

70499 

70529 

7o558 

2.yl 

1.70587 

70617 

70646 

70675 

70704 

70734 

70763 

70792 

70822 

7o85i 

I 

3 

2.92 

1.70880 

70909 

70939 

70968 

70997 

71026 

7io56 

71085 

71114 

71 143 

2 

6 

2.93 

1.71172 

71202 

7i23i 

71260 

71289 

7i3i8 

71348 

71377 

7i4o6 

71435 

3 

8 

2.94 

I. 71464 

71493 

7i523 

71552 

7i58i 

71610 

71639 

71668 

71697 

71727 

4 
5 

II 
i4 
17 

2.95 

1.71756 

71785 

71814 

71843 

71873 

71 901 

71930 

71959 

71988 

72017 

6 

2.96 

1 .72047 

72076 

72105 

72134 

73163 

72193 

72221 

7225o 

72279 

723o8 

7 

20 

2.97 

1.72337 

72  366 

73395 

72424 

72453 

72482 

72511 

72540 

73569 

73598 

8 

22 

3.98 

1.72627 

72656 

72685 

73714 

72743 

72772 

72800 

7282g 

72858 

72887 

9 

25 

2  4(9 

1.72916 

72945 

72974 

73oo3 

73o33 

73061 

73090 

73118 

73i47 

73176 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

2a 


TABLE  I.— OF  SQUARE  ROOTS. 

The  proposed  number  is  to  be  found,  as  far  as  the  second  decimal  place,  in  the  side  column  of  the  table,  and  the   third 
decimal  at  the  top  of  one  of  the  vertical  columns  ;  the  number  corresponding  is  the  required  root. 


0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

3.O0 

1.73205 

73234 

73263 

73292 

73321 

73349 

73378 

73407 

73436 

73466 

29 

3.01 

I .73494 

73522 

7355i 

73580 

73609 

73638 

73666 

73696 

73724 

73753 

— 

3.02 

I. 73781 

738ro 

73839 

73868 

73897 

73926 

73954 

73983 

740:1 

74o4o 

I 

3 

3.o3 

I .74069 

74098 

74126 

74:55 

74:84 

7421 3 

74241 

74270 

74299 

74327 

2 

6 

3.o4 

1.74356 

74385 

7441 3 

74442 

7447: 

74499 

74528 

74557 

74585 

746:4 

3 
4 

9 

12 

3.o5 

1.74642 

74671 

74700 

74728 

74757 

74786 

748:4 

74843 

74871 

74900 

5 

i5 

3.06 

1.74929 

74957 

74986 

76014 

76043 

76071 

76:00 

76129 

76167 

76186 

6 

17 

3.07 

1.75214 

75243 

76271 

75300 

75328 

75357 

75385 

75414 

76442 

7547: 

7 

20 

3.08 

I .75499 

75528 

75556 

75686 

756:3 

76642 

76670 

75699 

76727 

76766 

8 

23 

3.09 

1.75784 

75812 

75841 

76869 

76898 

76926 

76966 

75983 

7(3011 

76040 

9 

26 

3.10 

1 .76068 

76097 

76126 

76163 

76182 

76210 

76238 

76267 

76295 

76324 

3.11 

1.76352 

76380 

76409 

76437 

76465 

76494 

76622 

76660 

76679 

76607 

3.12 

1.76635 

76664 

76692 

76720 

76748 

76777 

76806 

76833 

76862 

76890 

3.i3 

I. 7691 8 

76946 

76976 

77003 

77o3i 

77069 

77088 

77116 

77144 

77172 

3.t4 

1.77200 

77229 

77267 

77286 

773:3 

77341 

77370 

77398 

77426 

77454 

3.i5 

1.77482 

775il 

77539 

77667 

77595 

77623 

7765: 

77679 

77708 

77736 

3.16 

I .77764 

77792 

77820 

77848 

77876 

77904 

77933 

7796: 

77989 

78017 

3.17 

I .78045 

78073 

78101 

78:29 

78:67 

78185 

78213 

7824: 

78269 

78298 

2» 

3.18 

1.78326 

78354 

78382 

784:0 

78438 

78466 

78494 

78622 

78660 

78678 

— 

3.19 

I .78606 

78634 

78662 

78690 

78718 

78746 

78774 

78802 

78830 

78867 

I 
2 

3 
6 

3.20 

1 .78885 

78913 

78941 

78969 

78997 

79026 

79063 

7908: 

^9',2§ 

79:37 

3 

8 

3.21 

I. 791 65 

79193 

79221 

79248 

79276 

793o4 

79332 

79^60 

79388 

79416 

4 

II 

3.22 

I .79444 

79471 

79499 

79627 

79555 

79583 

796:: 

79639 

79666 

79694 

5 

i4 

3.23 

1.79722 

79750 

79778 

79806 

79833 

79861 

79889 

79917 

79944 

79972 

6 

17 

3.24 

1 .80000 

80028 

80066 

8oo83 

80111 

80139 

80:67 

80194 

80222 

80260 

7 
6 

20 
22 

3.25 

1.80278 

8o3o5 

8o333 

8o36i 

8o388 

8o4i6 

80444 

80472 

80499 

80627 

9 

25 

3.26 

i.8o555 

8o582 

80610 

8o638 

80665 

80693 

80721 

80748 

80776 

80804 

3.27 

i.8o83i 

80869 

80887 

80914 

80942 

80970 

80997 

81026 

81062 

81080 

3.28 

1. 81 1 08 

8ii35 

8ii63 

8:191 

81218 

81246 

81273 

8i3oi 

8i328 

81 356 

3.29 

I. 81 384 

8i4ii 

81439 

81466 

81494 

81621 

81 54g 

81676 

81604 

8i63i 

3.3o 

I. 81659 

81687 

81714 

81742 

81769 

81797 

81824 

8i852 

81879 

81907 

3.3i 

I. 81934 

81962 

81989 

82016 

82044 

82071 

82099 

82126 

82164 

82181 

3.32 

1.82209 

82236 

82264 

82291 

823:8 

82346 

82373 

82401 

82428 

82455 

3.33 

1.82483 

82510 

82538 

82666 

82692 

82620 

82647 

82676 

82702 

82729 

3.34 

1.82757 

82784 

8281 1 

82839 

828(36 

82893 

82921 

82948 

82976 

83oo3 

27 

3.35 

1 .83o3o 

83o57 

83o85 

83ii2 

83 1 39 

83:67 

83i94 

83221 

83248 

83276 

I 

3 

3.36 

i.833o3 

8333o 

83358 

83385 

834:2 

83439 

83467 

83494 

83521 

83548 

2 

5 

3.37 

1.83576 

836o3 

83630 

83657 

83686 

837:2 

83739 

83766 

83793 

83821 

3 

8 

3.38 

1.83848 

83875 

83902 

83929 

83967 

83984 

84oii 

84o38 

84066 

84092 

4 

II 

3.39 

1. 84120 

84:47 

84174 

84201 

84228 

84265 

84282 

843io 

84337 

84364 

5 

A 

i4 
16 

3.40 

I .84391 

844 1 8 

84445 

84472 

84499 

84626 

84554 

84581 

84608 

84635 

7 

19 

3.41 

1 .846(52 

84689 

84716 

84743 

84770 

84797 

84824 

84851 

84878 

84906 

8 

22 

3.42 

1 .84932 

84959 

84986 

85oi  4 

86o4: 

86068 

86096 

86122 

85i49 

86176 

9 

24 

3.43 

1.85203 

8523o 

86267 

86284 

863i: 

85338 

86365 

85391 

854i8 

85445 

3.44 

1.85472 

85499 

86626 

85553 

86680 

86607 

85634 

86661 

86688 

86716 

3.45 

1.85742 

86769 

86796 

85822 

85849 

86876 

86903 

86930 

I'P'^J 

86984 

3.46 

1 .8601 1 

86o38 

86066 

86091 

861 1 8 

86:45 

86172 

86199 

86226 

86263 

3.47 

1 .86279 

863o6 

86333 

86360 

86387 

864:4 

86440 

86467 

8fi494 

86621 

3.48 

1 .86548 

86574 

86601 

86628 

86655 

86682 

86708 

86736 

86762 

86789 

3.49 

I. 8681 5 

86842 

86869 

86896 

86922 

86949 

86976 

87003 

87029 

87066 

3.5o 

I .87083 

87110 

87x36 

87:63 

87190 

872:6 

87243 

87270 

87297 

87323 

26 

3.5i 

1.87350 

87377 

87403 

87430 

87457 

87483 

87610 

87537 

87663 

87690 

— 

3.52 

1.87617 

87643 

87670 

87697 

87723 

87750 

87776 

87803 

87830 

87866 

I 

3 

3.53 

1 .87883 

87910 

87936 

87963 

87989 

880:6 

88043 

88o6() 

88096 

88122 

3 

5 

3.54 

I. 881 49 

88175 

88202 

88229 

88256 

88282 

883o8 

88335 

8836: 

88388 

3 
4 

8 

10 

3.55 

I. 8841 4 

88441 

88468 

88494 

8862: 

88647 

88674 

88600 

88627 

88653 

5 

i3 

3.56 

I .88680 

88706 

88733 

88769 

88786 

88812 

88839 

88866 

88892 

88918 

6 

16 

3.57 

1.8S944 

88971 

88997 

89024 

8go5o 

89077 

89103 

8gi3o 

89166 

89182 

7 

18 

3.58 

1 .89209 

89235 

89262 

89288 

893.5 

89341 

89367 

89394 

89420 

89447 

8 

21 

3.59 

1.89473 

89499 

89626 

89662 

89678 

89605 

89631 

89668 

89684 

89710 

9 

23 

0 

1 

2 

.3 

4 

.5 

6 

7 

8 

9 

TABLE  I.— OF  SQUARE  ROOTS. 


The  proposed  number  is  to  be  found,  as  far  as  the  second  decimal  place,  i 
decimal  at  tlie  top  of  one  of  the  vertical  columns  ;  the  number  conespouilins; 


the  side  column  of  the  table,  and  the  third 
1  tlic  required  root. 


3.60 

0 

1 

2 

3 

4 

5 

G 

7 

8 

9 

■.89-37 

89763 

89789 

89816 

89842 

89868 

89895 

89921 

89947 

89974 

27 

3.6! 

1.90000 

90026 

90053 

90079 

90106 

90182 

90168 

90184 

90310 

90287 

— 

3.62 

1 .90263 

90289 

903 16 

90342 

90868 

9o8g4 

90431 

90447 

90478 

90499 

I 

3 

3.63 

1 .90326 

90552 

90578 

90604 

90681 

90637 

90688 

90709 

90735 

90762 

2 

5 

3.64 

1.90788 

90814 

90840 

90866 

90898 

90919 

90945 

90971 

90997 

91024 

3 
4 

8 

3.6-5 

1.91050 

91076 

91102 

91128 

91154 

91181 

91207 

91288 

91269 

91285 

5 

i4 

3.66 

i.giSii 

91337 

91364 

91390 

91416 

91442 

91468 

91494 

91620 

91646 

6 

16 

3.67 

I. 91 572 

91599 

91625 

91631 

91677 

91708 

91729 

91766 

91781 

91807 

7 

'9 

3.68 

I. 91 833 

91859 

91885 

91911 

91937 

91964 

9' 990 

92016 

92042 

92068 

8 

22 

3.6y 

1.92094 

92120 

92146 

92172 

92198 

92224 

92260 

92276 

92802 

92828 

9 

24 

3.-0 

1.92354 

92380 

92406 

92432 

92468 

92484 

92610 

92686 

92662 

92688 

3.-I 

I. 92614 

92640 

93666 

93691 

92717 

93743 

92769 

92795 

92821 

92847 

3.72 

,.92873 

92899 

92925 

92951 

92977 

98008 

98028 

98064 

98080 

98106 

3.-3 

1.93132 

931 58 

93184 

98210 

98286 

98261 

98287 

98818 

93339 

93865 

3.-4 

I. 93391 

93417 

93442 

93468 

98494 

98620 

93540 

93572 

98698 

98628 

3.-5 

1 .93649 

93675 

93-01 

93727 

93752 

93778 

98804 

98880 

98856 

98881 

3.-6 

1 .93y07 

93933 

93959 

93985 

94010 

94o36 

94062 

94088 

941 1 3 

94189 

3.— 

1.94163 

9419' 

94216 

94242 

94268 

94294 

94819 

94345 

94371 

94397 

26 

3.-S 

1.94422 

94448 

94474 

94499 

94625 

94551 

94676 

94602 

94628 

94654 

— 

3.-9 

1.94679 

94705 

94731 

94756 

94782 

94808 

94888 

94869 

94885 

94910 

I 

3 
5 
8 

3.80 

1.94936 

94962 

94987 

9601 3 

96088 

96064 

95090 

96116 

96141 

96167 

2 
3 

3.81 

1.96192 

95218 

95243 

96269 

96396 

96820 

95346 

96871 

96897 

96428 

4 

10 

3.82 

1.95448 

95474 

95499 

95525 

96661 

96676 

96602 

96627 

96668 

96678 

5 

i3 

3.83 

1 .95704 

95729 

95755 

96780 

96806 

95832 

95857 

96888 

96908 

96934 

6 

16 

3.84 

1  -95959 

95985 

96010 

96086 

96&61 

96087 

96112 

96188 

96163 

96189 

7 
8 

9 

i8 

3.85 

1.96214 

96240 

96265 

96291 

96816 

96342 

96867 

96892 

96418 

96443 

21 
23 

3.86 

I  .Q6469 

96494 

96520 

96645 

96671 

96696 

96621 

96647 

96672 

96698 

3.87 

1 .96723 

96749 

96774 

96799 

96826 

96860 

96876 

96901 

96926 

96962 

3-88 

1 .96977 

97000 

97028 

97068 

97079 

97104 

97129 

97166 

97180 

97206 

3.S9 

1.97231 

97256 

97282 

97307 

97882 

97358 

97383 

97408 

97434 

97469 

3.90 

1.9-484 

97509 

97535 

97660 

97585 

97611 

97686 

97661 

97687 

97712 

3.91 

1.97-37 

97762 

97788 

97818 

97888 

97S64 

97889 

97914 

97939 

97965 

3.Q2 

i-9"99o 

98015 

98040 

98066 

98091 

981 16 

98141 

98167 

98192 

98217 

3.93 

1.98242 

98267 

98293 

98318 

98848 

98868 

98894 

98419 

98444 

98469 

3.94 

1.98494 

98520 

98545 

98670 

98696 

98620 

98645 

98671 

98696 

98721 

25 

3.Q5 

1.98746 

9877; 

98796 

9S822 

98847 

98872 

98897 

98922 

98947 

98972 

I 

3 

3.96 

1-98997 

99023 

99048 

99078 

99098 

99133 

99148 

99178 

99198 

99228 

2 

5 

3.97 

1.99249 

99274 

99299 

99824 

99349 

99374 

99399 

99434 

99449 

99474 

3 

8 

3.98 

1-99499 

99524 

99549 

99376 

99600 

99626 

99660 

99675 

99700 

99725 

4 

10 

3.09 

1.99750 

99775 

99800 

99826 

99850 

99875 

99900 

99926 

99950 

99975 

5 
6 

7 

i3 
i5 
18 

4.00 

2.00000 

00025 

ooo5o 

00076 

001 00 

00126 

00160 

00175 

00200 

00225 

4.01 

2.00230 

00275 

oo3oo 

00826 

oo35o 

00876 

oo4oo 

00425 

00449 

00474 

8 

20 

4.02 

2.00499 

00624 

00549 

00674 

00699 

00634 

00649 

00674 

00699 

00724 

9 

23 

4.o3 

2.00749 

00774 

00798 

00828 

00848 

00878 

00898 

00928 

00948 

00978 

• 

4.04 

2.00998 

01022 

01047 

01072 

01097 

01122 

01147 

01172 

01196 

01221 

4.o5 

2.01246 

01271 

01296 

01821 

01 345 

01870 

01896 

01420 

OI446 

01470 

4.06 

2.01494 

oi5i9 

01 544 

01669 

01694 

01 61 8 

01643 

01668 

01698 

01718 

4.07 

2.01742 

01767 

01792 

01817 

01842 

01866 

01891 

01916 

01941 

01966 

4.08 

2.01990 

0201 5 

02040 

02064 

02089 

02114 

02189 

02168 

02188 

022l3 

4.09 

2.02237 

02262 

02287 

02812 

02336 

02861 

02386 

02410 

02486 

02460 

4.IO 

2.02485 

02509 

02534 

02669 

02688 

02608 

02688 

02667 

02682 

02707 

24 

4.11 

2.02731 

02736 

02781 

02806 

02880 

02866 

028-9 

03904 

03929 

02968 

4.12 

2.02978 

o3oo2 

03027 

o3o63 

08076 

08101 

08126 

o8i5o 

08176 

08199 

I 

2 

4.1 3 

2.03224 

03349 

03273 

08298 

08822 

o8347 

08872 

08896 

03431 

03445 

2 

5 

4.i4 

2.03470 

03494 

o33i9 

03544 

03568 

03593 

c36i7 

o3642 

03666 

08691 

3 
4 
5 

7 

4.i5 

2.0371 5 

08740 

03765 

08789 

o38i4 

08888 

08868 

08887 

08912 

08936 

10 

12 

4.16 

2.03961 

03985 

o4oio 

o4o34 

04069 

o4o83 

04108 

04182 

04167 

o4i8i 

6 

i4 

4.17 

2.04206 

o43  3o 

04255 

04279 

o43o4 

04828 

04363 

04377 

o44o2 

04426 

7 

17 

4.18 

2.044 5o 

04475 

04499 

04524 

04548 

04578 

04597 

04633 

o4646 

04670 

8 

19 

4.19 

2.04695 

04719 

04744 

04768 

04793 

04817 

o484i 

04866 

04890  0491 5 

9 

22 

0 

1 

•2 

3 

4 

5 

6 

7 

8    9 

TABLE  I.— OF  SQUARE  ROOTS. 

The  proposed  number  is  to  be   found,  as  for  as  the  first  decimal   place,  in   the  side   column  of  the   table,  and  the   second 
decimal  at  the  top  of  one  of  the  vertical  cobimns  ;  the  number  correspondiiig-  is  the  required  root. 


4.2 
4.3 
4.4 
4.5 
4.6 

4.7 
4.8 

4.9 
5.0 
5.1 

5.2 

5.3 
5.4 
5.5 
5.6 

5.7 
5.8 
5.9 
6.0 
6.1 

6.2 
6.3 
6.4 
6.5 
6.6 

6.7 
6.8 
6.9 

7.0 
7-1 

7-2 
7.3 
7-4 
7-5 
7.6 


0 


2.04939 

2.07364 

3.09762 

2.12l32 
2.14476 

2.16795 
2.19089 
2.21359 
2.23607 
2.25832 

2.28035 
2.30217 
2.32379 
2.34521 

2.36643 

2.38747 
2.4o832 
2.42899 
2.44949 
2.46982 

2.48998 
2.50998 
2.52982 
2.54951 
2.56905 

2.58844 
2.60768 
2.62679 
2.64575 
2.66458 

2.68328 
2.70185 
2.72029 
2.-386I 
2.75681 


1 


?7489 
7.8    2.79285 
2.81069 
.82843 


7-9 


8.2 
8.3 
8.4 

8.5 
8.6 

8.7 
8.8 
8.9 
9.0 
9-' 

9.2 
^.3 
9.4 

9 
9.6 

9■■^ 
9.8 

9-9 
1 0.0 
I  o.  I 


o5i83 
07605 
1 0000 
12368 
14709 

17025 
19317 
2i585 
2383o 
26053 

28254 
3o434 
32594 
3473.  ■ 
36854 

38956 
4io3q 
43io5 
45i53 
47184 

49199 
51197 
53i8o 

55i47 
57099 

59037 
60960 
62869 
64764 
66646 

685i.'i 
70370 
72213 
74o44 
75862 

77669 
79464 
81247 
83019 


2.846o5  84781 


2.86356 
2.88097 


2.91548 
2.93258 

2.94958 
2.96648 
2.g8329 
3.00000 
3.01662 

3.o33i5 
3.04959 
3.06594 
3.08221 
3.09839 

3.11448 
3.i3o5o 
3.14643 
3.16228 
3.17805 

0 


8653i 


05426 
07846 
10238 
12603 
14942 

17256 
19545 
21811 
24o54 
26274 

28473 
3o65i 
32809 
34947 
37065 

39165 
41247 
433ti 
45357 
47386 

49399 
51396 
53377 
55343 
57394 

59230 

6ii5 

63o59 

64953 

66833 

68701 
70555 
72397 
74226 
76043 

77849 
79643 
8i425 
83196 
84956 

86705 


oSôyo 
08087 
1 0476 
12838 

1 5x74 

17486 
19773 

22036 

24277 

26495 

28693 
3o868 
33o24 
35i6o 
37276 

39374 
41454 
43516 
45561 
47588 

49600 
51595 

5357' 
55539 
57488 

59422 
61 343 
63249 
65i4i 
67021 


05913 
08327 
10713 
i3o73 
i54o7 

17715 
20000 
22261 
24499 
26716 

28910 
3io84 
33238 
35372 
37487 


5 


061 55 
08567 
10950 
i33o7 
1 5639 

17945 
20227 
22486 
24722 
26936 

29129 

3i3o 

33452 

35584 

37697 


39533  3979 
■  ""  41868 
43926 
45967 
4799 


90000 

^719 
93428 

95127 
96816 
98496 
00167 
01828 

o348o 
o5i23 
06757 
o8383 


11609 
13209 
14803 
i6386 
17962 

1 


90172 
91 890 
9359S 

95396 
96985 
9866/ 
oo333 
01993 

o3645 
05287 
06920 
08545 
10161 

11769 
i336g 
14960 
i6544 
18119 


70740 
72580 
74408 
76225 

78039 
79821 
8i6o3 
83373 
85i32 

86880 
88617 
90345 
93062 
93769 

95466 
97153 


oo5oo 
o3i59 

o38o9 
o545o 
07083 

08707 

10322 


41661 
43721 
45764 
47790 

49800 
51794 
53772 
55734 
57682 

59615 
61  534 
63439 

6533o 
67208 

69072 
70924 
72764 
74591 
76405 

78209 
80000 
81780 
83549 
85307 

87054 
88791 
905 17 
92233 
93939 

g5635 
97321 
9899S 
00666 
02324 

03974 
o56i4 
07246 
0S869 
10483 


I 


5oooo 

51992 
5396g 
55930 
57S76 

59808 

61725 
6363g 
655i8 
67395 

69258 
71109 
72947 
-4773 
76586 

78388 

801 

8ig57 

83735 

85482 


06398 
08806 
11187 
i3542 
15870 

18174 
20454 
22711 
24944 
27156 

29347 
3i5i7 
33666 
35797 
37908 

40000 
42074 
44i3i 
46171 
48193 

5o200 

53190 
54i65 
56i35 
58070 

60000 
61916 
638i8 

65707 
67582 

6g444 
71293 
73i3o 
74955 
76767 

78568 
80357 
82135 
83901 

85657 


06640 
09045 
11434 
13776 
1 61 02 

i84o3 
20681 
22935 
35167 
27376 

29565 
31733 
3388o 
36oo8 
38ii 

40208 

43381 

44336 

4637, 

48395 

5o4oo 
52389 
54363 
56320 
58263 

60193 
63107 
64008 
65895 
6776g 

6962g 

71477 
733i3 
75i36 
76948 

78747 
8o535 

823l2 

84077 
85832 


9 


iig2g  i2ogo 
13528  i3688 
15278 
16860 


i5ii9 
16703 
18377 


18434 


8733: 

88g64 

90689 

92404 

94109 

95804 
9748g 
99166 
00833 
02490 

o4i38 
05778 
07409 
ogoSi 
10644 

I2250 

1 3847 
1 5436 
17017 
1859, 

5 


06882 
09284 
11660 

i4oog 
i6333 

1 8633 
20907 
23i5g 
25389 
27596 

29783 
3ig48 
34094 
36220 
38328 

4o4i6 
42487 
44540 
46577 
48596 

5o5gg 
52587 
54558 
565 1 5 
58457 

6o384 
62298 
64197 
66o83 
67955 

69815 
71662 
73496 
753i8 


07123 
og523 
1 1 896 
14243 
1 6564 

18861 
3ii33 
33383 
2  56io 
37816 

3oooo 
32164 
34307 
36432 
38537 

40624 
42693 
44745 
46779 
48797 

50799 
52784 
54755 
56710 
5865o 

60576 
62488 
64386 
66371 
68143 

70000 
71846 
73679 
755o( 


77128  77308 


87402 
8gi37 
90861 
92575 
94279 

9^973 
97658 
99333 
00998 
02655 

o43o3 
o5g4i 
07571 
09193 
io8o5 

1 2410 
i4oo6 
i55g5 
17175 
18748 

6 


87576 
89310 

gio33 
92746 
94449 

96142 
97825 
99500 
01164 
02820 

04467 
061  o5 
07734 
09354 
10966 

12570 
i4i66 
15753 
17333 
18904 


78g37 
80713 
8348g 
84353 
86007 

87750 


gi204 
92916 
g46i8 

96311 

97993 
99666 
oi33i 
02985 

o463i 
06268 
07896 
09516 
11127 

12730 
14325 
iSgii 
17490 
19061 

8 


79106 
80891 
82666 
84429 
86182 

87924 
89655 
91376 
93087 
94788 

9647g 
98161 
99833 

ùi4g6 
o3i5o 

04795 
0643 1 
080  58 
09677 
11288 

1 2890 
14484 
16070 
17648 
19218 


246 

215 

344 

243 

242 

241 

240 

23D 

238 

237 

236 

235 

234 

1 

2.5 

i'l 

24 

24 

24 

24 

21 

24 

24 

24 

24 

24 

23 

i> 

4;i 

4H 

4H 

4!l 

4,s 

4K 

4rt 

4K 

4H 

47 

47 

47 

47 

:t 

74 

74 

7:t 

73 

7;! 

72 

72 

72 

71 

71 

71 

71 

70 

•1 

iW 

».s 

!)H 

i)7 

97 

(III 

»(i 

«m 

il.'i 

11.5 

ill 

iH 

!)4 

;", 

l-i;l 

12:! 

122 

122 

121 

121 

1211 

1211 

11:1 

lUI 

IIH 

11.^ 

117 

( 

I4K 

147 

mi; 

14« 

14.5 

14.5 

144 

1 1:1 

I  1:1 

112 

142 

141 

140 

7 

172 

172 

171 

1711 

llW 

l(i! 

ir„s 

11,7 

1117 

ICI, 

1115 

1115 

1114 

h 

1!)7 

HI;. 

111.", 

i:m 

I'.ll 

Hi:' 

|.|., 

l!l! 

I'.lii 

I'.ln 

i.-<;i 

MH 

1H7 

S) 

231 

221 

22U 

21» 

21b 

217 

211) 

2i;. 

214 

21a 

212 

212 

211 

233 

232 

231 

230 

229 

*28 

227 

226 

22.5 

224 

•^3 

2-Î2 

221 

2:h 

23 

& 

23 

23 

23 

23 

23 

23 

00 

22 

-» 

22 

47 

411 

4li 

411 

411 

4il 

4.5 

45 

45 

45 

45 

44 

44 

711 

70 

m 

(iil 

(iil 

(1.-^ 

68 

118 

118 

117 

67 

67 

m 

H:l 

!I3 

m 

(12 

H2 

HI 

111 

illl 

00 

!I0 

8« 

8!l 

88 

11- 

iir, 

116 

115 

115 

114 

M  1 

11:1 

113 

112 

112 

111 

HI 

1  111 

1:1' 1 

IH!1 

ins. 

v.r, 

i:!7 

lllll 

13,1 

135 

131 

134 

133 

133 

II  ill 

111" 

1(1" 

1111 

111(1 

Kill 

I5;i 

15s 

15K 

157 

1.51. 

1.55 

1.55 

ISd 

IKi, 

1K5 

184 

IKli 

1R2 

182 

181 

180 

179 

178 

178 

177 

210 

209 

208 

207 

20U 

205 

204 

203 

203 

202 

20J 

200 

199 

220 

219 

218 

217 

216 

215 

214 

213 

212 

211 

210 

209 

1 

22 

22 

22 

22 

22 

22 

21 

21 

21 

21 

21 

21 

" 

44 

44 

44 

43 

43 

43 

43 

43 

42 

42 

42 

42 

3 

(16 

66 

65 

65 

65 

65 

64 

64 

64 

63 

(13 

63 

4 

88 

R8 

87 

87 

86 

86 

86 

85 

85 

84 

84 

84 

5 

110 

nil 

109 

109 

108 

108 

1117 

107 

106 

106 

105 

lO.-i 

6 

132 

131 

131 

130 

130 

129 

12^ 

128 

127 

127 

126 

12^5 

7 

1.54 

1.53 

1.53 

1,52 

151 

151 

1511 

149 

148 

148 

147 

141. 

8 

176 

175 

174 

17^ 

173 

172 

171 

1711 

170 

U19 

168 

167 

9 

198 

197 

196 

195 

194 

194 

193 

192 

191 

190 

189 

las 

21 

42 

ca 

83 
104 
125 
146 
166 
187 


207 

206 

205 

204 

203 

202 

201 

200 

199 

198 

197 

196 

195 

1 

21 

21 

21 

20 

20 

20 

20 

20 

20 

211 

2,1 

20 

20 

2 

41 

41 

41 

41 

41 

40 

40 

40 

40 

40 

39 

39 

39 

3 

62 

62 

62 

fil 

61 

61 

60 

60 

110 

.59 

59 

.59 

59 

4 

83 

82 

82 

82 

81 

SI 

RO 

8(1 

80 

79 

79 

78 

78 

5 

104 

103 

103 

102 

102 

101 

101 

100 

mil 

99 

99 

9s 

98 

6 

124 

124 

123 

19,2 

122 

1"1 

121 

120 

119 

119 

118 

lit 

117 

145 

144 

144 

143 

141 

1  11 

111 

MO 

139 

139 

Kt 

137 

137 

8 

166 

165 

164 

163 

162 

1112 

161 

lllll 

159 

158 

15,- 

l.)V 

1.56 

9 

186 

185 

185 

184 

183 

182 

181 

180 

179 

178 

177 

176 

17d 

180 

185 

184 

183 

Ifl 

19 

18 

18 

37 

37 

37 

37 

.56 

.56 

55 

55 

74 

74 

74 

73 

93 

93 

92 

92 

112 

111 

no 

no 

130 

130 

129 

128 

149 

148 

147 

141. 

107 

107 

166 

165 

182 

13 
36 
55 
73 
91 
109 
127 
146 
164 


181 

180 

179 

178 

177 

176 

175 

174 

173 

172 

171 

170 

109 

18 

18 

18 

18 

IS 

18 

18 

17 

17 

17 

17 

17 

17 

36 

.311 

36 

36 

35 

.35 

35 

35 

.35 

34 

31 

34 

34 

54 

54 

54 

53 

.53 

.53 

.53 

.52 

.52 

.52 

.51 

51 

bl 

7.) 

72 

75 

71 

71 

70 

70 

70 

69 

69 

68 

68 

68 

91 

90 

90 

89 

89 

88 

88 

87 

87 

86 

86 

85 

85 

109 

108 

107 

107 

106 

106 

105 

101 

104 

103 

103 

102 

101 

107 

126 

12.5 

12.5 

124 

123 

123 

122 

121 

120 

12(1 

119 

118 

145 

144 

143 

142 

142 

141 

11(1 

1119 

13S 

13S 

1:1, 

136 

135 

163 

102 

161 

160 

159 

108 

158 

1;., 

I06 

15j 

lu4 

1j3 

152 

108 

167 

166 

165 

164 

163 

162 

161 

160 

1,59 

1.58 

157 

156 

17 

17 

17 

17 

16 

16 

16 

16 

16 

16 

16 

16 

16 

34 

33 

33 

33 

33 

33 

32 

IfJ 

32 

32 

32 

31 

31 

50 

50 

.50 

50 

49 

49 

49 

48 

48 

48 

47 

47 

47 

67 

67 

66 

66 

66 

65 

65 

64 

IH 

64 

113 

113 

62 

84 

84 

83 

83 

82 

82 

81 

81 

80 

80 

711 

79 

78 

nil 

lllll 

IOO|   99 

98 

98 

97 

97 

91. 

95 

95 

94 

94 

IIS 

117 

nil 

116 

115 

114 

113 

113 

112 

111 

1  1  1 

nil 

109 

134 

134 

1.33 

132 

131 

130 

130 

129 

12s 

127 

12  1 

126 

126 

151 

150 

149 

149 

148 

147 

146 

145 

144 

143 

142 

141 

140 

TABLE  II. 

This  gives  ilie  time  7"  of  describing  a  parabolic  arc  by  a  comet,  tlie  sum  of  tlie  extreme  radii  r  -\- r'   being  found  at  llji 
top,  anil  the  chord  c  at  the  left  side  of  tlie  pace. 


Sum  .)!  thu  ra.lll   r   ■- r  .                                                                                                                      | 

Chord 
C. 

0,01 

0,0-2 

0,03 

0,04 

0,05 

0,00 

0,07 

0,08 

0,09 

0,10 

0,11 

Days  lilif. 

Days  III  if. 

Days  ](lil'. 

Days  Idif. 

Days  |(lif. 

Days  |dif. 

Days  |iiil 

Days  Idil". 

Days  l.lif. 

Days  lijif. 

Days  |dif. 

0,00 
0,01 
0,02 

o,o3 
0,04 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 

0,00c 
0,027 

i4 

0,000 
o,o4l 
o,t>-8 

9 
11 

o,oiio 
o,o5o 
0,099 
0,143 

8 

1->,0(X 

o,o58 
0,11 5 

0,!~0 

0,31  g 

i4 
33 

0,000 
o,o65 
0,129 
0,193 

0,232 

o,3o6 

6 
i3 
■9 

37 

38 

OjOOt 

o,t)7i 
0,143 
0,211 
0,279 

0,344 
o,4o3 

6 
1 1 
18 
24 

3i 
4i 

(>,000 

0,077 

0,1 53 
0,339 
o,3o3 

0,375 
0,444 
o,5o8 

5 
ti 
16 
22 

30 

36 

45 

0,000 
0,082 
0,164 
0,345 
o,3a5 

o,4o4 
o,4So 
0,553 
0,620 

5 
10 

i5 

31 
26 

33 

4o 
49 

0,000 
0,08" 
0,174 
0,360 

0,346 

o,43o 
o,5i3 
0,593 
o,6()9 

0,740 

5 
to 
i5 
'9 

25 

3o 
36 
AA 
53 

0,OOCJ 

0,093 

0,184 
0,275 

o,365 

0.455 
o;543 
0,629 
0,71 3 
0,793 

0,867 

4 

â 
18 

23 

28 
33 
39 
46 

56 

0,000 
0,096 
o,lg3 
0,288 
0,383 

0,478 
0,571 
0,662 
0,752 
o,83g 

0,923 
1 ,000 

5 

8 

i3 

18 

22 

27 

32 

37 
43 

59 

0,0000 
0,0001 

o,oot.v^ 

0,00(KJ 

0,001'' 

0,00  2  ^ 

o,oo3(') 
0,0049 
0,0064 
0,008 1 

0,0100 
0,0121 

0,0001 1 

0,0002 

0,0004 

0,0008 

0,0012 

0,0018| 

0,0024  0,0032| 

0,0040 

0,0050j 

0,0061 

0 

\  •  {  r  -\-  r'  )-    or   r^  -|-  r"*    nearly.                                                                                                 | 

TABLES  rOR  COMPUTING  THE  ORBIT  OF  A  COMET. 
Table  I.  This  is  a  table  of  square  roots,  adapted  to  the  calciilalion  of  the  orbit  of  a  Comet,  by  methods  similar  to  tha' 
proposed  by  Dr.  Olbers.  AVe  have  by  inspection,  in  this  table,  the  root  of  any  number,  from  0,001  to  10,19  ;  and  by 
using  the  small  tables  of  proportional  parts,  given  in  the  margin,  the  root  may  he  obtained  Jrom  the  number,  or  the 
number  from  the  root,  to  five  places  of  decimals.  This  requires  no  particular  explanation,  since  the  arrangement  is  the 
same  as  that  of  a  common  table  of  logarithms.  We  may  also  observe  that  when  the  quantity  .r,  whose  root  is  to  be  found, 
is  less  than  0,102,  it  is  convenient  to  find  the  root  of  lOOx,  and  then  divide  the  result  by  10  ;  which  is  done  by  merely 
transposing  the  decimal  point.  Thus  if  x^  0,0961,  we  may  find  the  root  of  9,61  =3,1,  and  transpose  the  point  one  figure, 
and  we  shall  obtain  4/ 0,0961  =0,31.  In  like  manner,  if  we  have  c3  =  0,080087,  we  get  by  the  table  v/ 8,0087  =  2,82996, 
whence  c  =  0,282996  ;  by  this  means  the  proportional  parts  are  more  easily  obtained. 

Table  II.  The  argument  at  the  top  of  the  table  is  the  sum  of  the  two  radii  vectores  of  the  comet  r,  r"  ;  the  mean 
distance  of  the  earth  from  the  sun  being  taken  for  unity.  On  the  left  side  column  of  the  table,  is  the  length  c  of  the 
chord,  connecting  the  extreme  parts  of  these  radii.  The  corresponding  number  represents  the  time  T,  given  by 
Lambert's  formula  [750,  750']  ;  supposing  the  comet  to  move  in  a  parabolic  orbit, 

T=9''^'",688724.f(r+r"+c)t  — (r+r"— e)f|. 

Thus  if  r4-r"  =  2,20,  and  c  =  0,20,  we  shall  have  r=8''''''^619.  The  proportional  parts  for  the  fractions  of  r  -f  r" 
beyond  two  places  of  decimals,  are  placed  at  the  right  hand  side  of  the  page,  those  for  c,  in  the  column  at  the  bottom  of 
the  table,  nearly  below  the  corresponding  tabular  time  T.  In  using  Table  II.  we  must  enter  it  with  the  values  of  r-{-r" 
and  c  ;  taking  them  to  t%vo  places  of  decimals  ;  and  find,  by  inspection,  the  corresponding  chief  term  of  T.  The  variation 
of  T,  corresponding  to  the  successive  tabular  values  of  r  -\-  r",  is  given  in  the  same  horizontal  line  with  the  chief  term 
of  T;  and  we  must  find  also  the  variation,  corresponding  to  the  successive  tabular  values  of  c,  in  the  vertical  column, 
immediately  below  the  chief  term  of  T".  The  increments  of  T,  corresponding  to  the  fractional  parts  of  r  +  r"  and  c. 
beyond  the  second  decimal  place,  are  to  be  found  and  added  to  the  chief  term  T,  to  obtain  the  true  value' of  T. 

In  general  it  will  be  sufficiently  accurate  to  use  for  the  argument  of  the  proportional  parts  in  the  table  in  the  side 
column,  the  tabular  number  in  the  column  of  differences  corresponding  to  the  chief  term  of  T;  but  when  very  great 
accuracy  is  required,  we  may  find  it  for  the  exact  value  of  c  ;  by  taking  a  proportional  part  of  the  difference  of  the  two 
nearest  numbers  in  the  table. 

To  show,  by  an  example,  the  use  of  this  table,  we  shall  suppose  r-(-r"=  1,96280,  c  =  0,21.573.    Then  we  shall  have  for 

the  chief  term  of  T,  corresponding  to  1,96  and  0,24  the  value  9    ^  ,760  ;  the  differences  between  this  and  the   next 
numbers  being  25,  and  406,  respectively.     The  proportional  parts  corresponding  to  the  decimals  ,00280  and  ,00573  are  7 

and  233  ;  the  sum  of  these  three  quantities  is  9,760  -\-  0,007  +  0,233  =  10''*^^  the  value  of  T  required. 

In  the  right  hand  column  of  the  table  is  given  the  value  of  c~.  At  the  bottom  of  the  table  is  given  the  values  of 
.J  .  (r -)- r")  2,  which  maybe  used,  instead  of  r3 -[-r"2,  in  the  first  approximation  to  the  value  of  ç.  In  this  case  the 
calculation  is  made  merely  by  inspection  ;  using  the  nearest  numbers  in  the  table,  and  taking  them  to  one  or  two  places 
of  decimals  ;  without  using  the  tables  of  proportional  parts,  which  are  exclusively  adapted  to  the  values  of  r  -^  r"  and  c. 

These  two  tables  are  designed  to  facilitate  the  computation  of  the  value  of  g,  from  the  three  equations  {A),  (B),  {  C), 
which  are  similar  to  these  in  the  following  system  ;  in  which  r,r"  represent  the  radii  vectores  at  the  first  and  third 
observations;  c  the  intercepted  chord  ;  ^  the  curtate  distance  0/  the  comet  from  the  earth;  the  interval  bettueen  the 
observations,  expressed  in  days,  being  given  and  represented  by  T.  The  equation  (  /)  )  which  is  the  sum  of  the 
equation  (.4),  (B),  may  be  used  in  the  first  approximation  to  the  value  of  §.  It  is  not  absolutely  necessary,  to  use 
the  equation  (  Z)  ),  but  it  will  frequently  be  found  to  have  a  tendency  to  abridge  the  calculations. 

3a 


TABLE  II. 

This  gives  the  time  Tof  describing  a  paraboUc  arc  by  a  comet,  the  sum  of  the  extreme  radii  r  - 
top,  and" the  chord  c  at  the  left  side  of  the  pace. 


;•"  bein^  found  at  the 


Sum  of  the  liadii  r  -r  r",                                                                                                      | 

Chord 
C. 

0,12 

0,13 

0,14 

0,15 

0,16 

0,17 

0,18 

0,19 

0,20 

0,2 

1 

iiT?. 

0,22 

Days  !dif. 

Days  |dif. 

Days  |ilir. 

Days  Idil'. 

Days  |dil. 

Days  |dil'. 

Days  lilil. 

Days  |dir. 

Days  |dif. 

Days 

Days  [liif. 

0,00 

0,000 

0,000 

0,000 

11,000 

0,000 

0,000 

0,000 

u,ooo 

0,000 

0,000 

0,000 

O.ljOOO 

0,01 

0,701 

4 

0,103 

4 

o,Ioq 

4 

0,11 3 

3 

0,116 

4 

0,120 

3 

0,1  23 

4 

0,127 

3 

0,1 3o 

3 

0,1 33 

3 

0,1 36 

3 

0,0001 

0,02 

0,201 

8 

o,2oq 

8 

0,217 

S 

0,225 

7 

0,232 

8 

0,240 

7 

0,247 

6 

0,2b3 

7 

0,260 

b 

0,266 

7 

0,273 

6 

o,ooo4 

o,o3 

o,3oi 

1 3 

o,3r4 

12 

0,326 

1 1 

0,337 

1 1 

0,348 

1 1 

0,359 

I  I 

0,370 

10 

o,38o 

10 

0,390 

9 

o,3qq 

10 

o,4og 

9 

O.ÛOWJ 

o,o4 

0,401 

17 

0,418 

16 

0,434 

i5 

0,449 

i5 

o,464 

i4 

0,478 

i4 

0,492 

i4 

o,5o6 

i3 

0,519 

i3 

0,532 

i3 

0,545 

12 

0,0010 

o,o5 

0,300 

21 

0,521 

20 

o,54i 

iq 

0,560 

IQ 

o,57q 

18 

0,597 

18 

0,61 5 

17 

0,632 

16 

0,648 

16 

0,664 

16 

0,680 

16 

0.0025 

0,06 

o,5q8 

25 

0,623 

24 

0,647 

24 

0,671 

22 

0,693 

22 

0,71 5 

21 

o,736 

21 

0,757 

20 

0,777 

IQ 

0,790 

IQ 

0,81 5 

iq 

o,oo35 

0,07 

o,6q4 

3o 

0,724 

29 

0,753 

28 

0,781 

36 

0,807 

26 

0,833 

25 

0,858 

24 

0,883 

23 

o,9o5 

23 

0,928 

22 

0,950 

23 

0,0049 

0,08 

0,789 

35 

0,824 

33 

o,857 

32 

0,889 

3i 

0,920 

29 

o,q4q 

29 

0,978 

28 

1,006 

27 

i,o33 

2b 

i,o5q 

25 

1,084 

25 

0,0064 

0,09 

0,882 

40 

0,922 

38 

0,960 

37 

0.997 

35 

I,032 

33 

i,o65 

33 

1,098 

3i 

1,1 2g 

3i 

1,160 

29 

1,189 

29 

1,218 

28 

o,ùo8 1 

0,10 

0,972 

46 

1,018 

A4 

1,062 

4i 

i,io3 

3q 

I,l42 

38 

1,180 

36 

1,216 

35 

I,25l 

35 

1,286 

33 

i,3i9 

32 

1, 35 1 

32 

0,0100 

0,11 

1,069 

53 

1,112 

4q 

1,161 

46 

1,207 

44 

1,25: 

42 

1,293 

4i 

1,334 

39 

1,373 

38 

1, 41 1 

36 

1,447 

36 

1,483 

35 

0,0121 

0,12 

1, 1 39 

62 

1,201 

56 

1,257 

32 

1 ,3f!9 

4q 

1,358 

47 

r,4o5 

45 

1 ,45o 

43 

1,493 

43 

1,535 

40 

1,575 

3q 

1, 61 4 

3q 

0,01 44 

o,i3 

1 ,284 

66 

1,330 

58 

i,4oS 

55 

1.463 

32 

i,5i5 

4q 

1,564 

47 

1 ,61 1 

46 

1,657 

45 

1,702 

4i 

i,74:> 

4i 

0,0169 

o,i4 

1,435 

68 

i,5o3 

62 

1,565 

57 

1,623 

54 

1,676 

52 

1,728 

5o 

1,77a 

49 

1,827 

4l 

1,874 

45 

0,01 96 

0,1 5 

i,5q2 

71 

T,fi63 

64 

1,727 

5q 

1,786 

57 

1,843 

55 

i,8q8 

32 

1,950 

5i 

2,001 

49 

0,0225 

0,16 

1.754 

73 

1,827 

66 

I,8q3 

63 

1,956 

59 

2,01 5 

:)7 

2,072 

53 

2,13- 

3û 

0,0356 

0,17 

1,921 

75 

1,996 

6q 

2,o65 

65 

3,1  3o 

62 

2,192 

59 

2,25l 

38 

0,0289 

0,18 

2,093 

78 

2,171 

71 

2,242 

67 

2,30Q 

63 

2,374 

61 

o,o324 

0,19 

2,270 

So 

3,35o 

74 

2,434 

69 

3,493 

67 

o,o36 1 

0,20 

2,45 1 

83 

2.534 

-6 

2,6tO 

72 

o,o4.x> 

0,21 

2,637 

85 

2,722 

78 

0,044 1 

0,22 

2,82s 

87 

o,o484 

,0072 

,0085 

,0098 

,0113 

,0128 

,0145 

,0162 

,0181  1  ,0200 

,0221  1  ,0242 

'^ 

4  .   (  r  +  J-"  )=    or    r''  +  r'"  nearly.                                                                                              | 

80 

83 

86 

89 

92 

95 

98 

8 

8 

9 

9 

9 

10 

10 

16 

17 

17 

18 

18 

IQ 

20 

24 

25 

26 

27 

28 

29 

2q 

32 

33 

M 

36 

37 

38 

3q 

4o 

42 

43 

45 

46 

48 

4q 

48 

5o 

53 

53 

55 

57 

5q 

56 

58 

60 

62 

64 

67 

69 

64 

66 

6q 

71 

74 

76 

78 

72 

75 

77 

80 

83 

86 

88 

Proporliona 

parts  for  the  Chord. 

lOI 

104 

107 

no 

ii3 

116 

119 

123 

125 

128 

i3i 

i34 

1 37 





— 













_. 





10 

10 

1 1 

1 1 

1 1 

12 

12 

12 

i3 

i3 

i3 

i3 

14 

20 

21 

21 

32 

23 

23 

24 

24 

25 

26 

26 

27 

27 

3o 

3i 

32 

33 

34 

35 

36 

37 

38 

38 

39 

4û 

4i 

40 

42 

43 

A4 

45 

46 

48 

4q 

5o 

5i 

52 

54 

65 

5t 

53 

54 

55 

57 

58 

60 

61 

63 

64 

66 

67 

69 

61 

62 

64 

66 

68 

70 

71 

73 

75 

77 

79 

80 

82 

71 

73 

75 

77 

79 

81 

83 

85 

88 

90 

95 

94 

96 

Si 

83 

86 

8S 

90 

q3 

q5 

q8 

100 

102 

io5 

107 

no 

91 

94 

96 

99 

102 

io4 

107 

no 

1x3 

ii5 

118 

121 

123 

E  X  A  M  P  L  E    I  . 

To  show  the  use  of  these   tables  we  shall   apply  them  to  the  <letermination  of  the  value  of  g  from  tlie  three  followina 

equations,  correspondinç  to  observations  of  the  Comet  of  1779  ;  as  in  page  xiii.  of  Dr.  Olbers'  Jlhhaiidlung,  &,c. 

r2=0,9S240  4-0,87363.ç-l-2,33263.§2;  (A) 

r"2  =  0,98361  4- 2,llSC9.ç  +  2,88041.52  ;  (B) 

(;2  — 0,04133  4- 0,006845. §  +  0,208501. §2;  (  C) 

r3  +  r"-3  =  1,97101  -f-2,99232.g  +  5,21304.ç2  .  (  Z)  ) 

Time  T=  ll''='y^834 . 


COMPUTATION    OF  p  FROM    THE    ABOVE    EQUATIONS, 

(./!),  (E),(C). 


r2. 

r'la. 

C2. 

r,  r",  c. 

T. 

Hypolhesisl. 
g  =  0,3 

0.98240 
0,26209 
0,20994 

0,98861 
0,63560 
0,25924 

0,04168 
,00205 
,01876 

r  =1,20599 

r"=  1,37239 

r+r"  =  2,57838 

c   =0,2.5038 

11,645 
19 
18 

11,682 

1,45443 

1,88345 

0,06269 

Hypothesis  II. 
Add  -^^  makCB 
§=0,3075 

0,98240 
,26864 
,'^057 

0,98861 
,65149 
,27236 

0.041830 
.002104 
,019716 

0,063700 

r  =1,21311 

r''=  1,3829] 

I- -j- I-' =2,59602 

c   =0,25239 

11,690 
13 
111 

1,47161 

1,91216 

11,814 

Hypothesis  III. 
Add  ^-i-y  or  ,00123 
5  =  0,30873 

0,98240 

0,26971 

,22233 

0,98801 
,65410 
,27454 

0,041880 
,002112 
,019374 

r  =1,21427 

r'=  1,38405 

r+r"=2,,59892 

c   =0,25271 

11,090 
20 
127 

1,47444 

1,91725 

0,063866 

11,837 

Hypothesis  IV. 

^"Wtju  "  .MOIS 
J  =  0,30858 

0,98240 
,26958 
,22211 

0,98861 
,05377 
,27427 

0,041880 
,002111 
,019854 

r  =1,21412 

r"=  1,38413 

r+j-"  =  a,59a55 

c   =0,25207 

11,090 

19 

125 

1,47409  1  1,91 61.5 

0,003845 

11,834 

Coetlicients  of  Ç.* 


0,S73C3 


0,20209 
655 


0,26864 
107 


-âTTUtr 


0,20971 
—13 


0,26958 


2,llSi,9 


0,63500 
1589 


0,65149 
2G1 


0,05410 
—33 


0,6537' 


,002053 
51 


,002104 

8 


,002112 


,002111 


CoefBcienlsof  g^ 


2,33203 


2,8804110,208501 


A 


0,20994 

1050 

13 


0,2.592410,018766 
1296  938 

16  12 


Ï5ÎT 
"bUt!' 

-TSUTT 


0,22057 
170 


0,9-^33 
—22 


0,27230 
218 


0,019716 
158 


0,274,54  0,019874 

—27 1        _20 


0,274271   ,1119854 


TABLE  II. 

This  gives  tlie  time  IT  of  dcscrihiiii;  a  parabolic  arc  by  a  comet,  the  sura  of  tlie  extreme  radii  r  -{->■' 
top.  and  the  chord  i-  at  tlio  lelt  siile  of  the  paiie. 


liciiiT  luiiml    at   tin 


t^iimi'l'tho   Kailii   r~\-r". 


Cboril 

c. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
o,c6 
0,07 
0,08 
0,09 

o,io 
0,1 1 
0,13 
0,1 3 
o,i4 

0,13 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,3.2 
0,23 
0,24 

0,25 

0,26 
0,27 
0,28 
0,39 


0.-23 


Days  jdil" 


0.000 
0,139 
0,2 
0,41  S 
0,557 

0,696 
0,834 
0,972 
1,109 
1,246 

1,383 
i,5i8 
1 ,653 
1 ,786 
1,919 

2,o5o 
2,180 
3,309 

2,435 

2,56o 

3,683 

3,800 

2,915 

3,033 


.0-26.= 


0.-24 


Days  |.lil'. 


o,oou 

0,l42 

o,2S5 
0,437 
0,569 

0,711 

o,85 

0,993 
1, 1 34 
1,274 

i,4i3 
1,553 
i,6go 
1,837 
1,963 

2,098 

3,332 

2,364 

2,495 

2,634 
3,75o 

2,874 
3,995 

3,112 
3,322 


0,25 


Days  lilif. 


,0288 


<.),00( 

0,145 
0,291 
0,436 
o,58i 

0,725 
0,870 
I, or  4 
1,1 58 
i,3oi 

1,443 
1,585 
1,736 
1,867 
3,006 

3,1 45 
3,383 
2,4i8 

3,552 

2,685 

3,816 
3,945 
3,073 
3,195 
3,3i4 

3,435 


,0313 


0,26 


Days  |(lir 


o,uoo 
0,1 48 
0,396 
0,444 
0,592 

o,74o 
0,887 
i,o34 
1,181 
1,327 

1,473 
1,618 
1,762 
1 ,906 
2,048 

3,190 
2,33i 
3,470 
3,601 

2,74 

2,880 

3,01 

3,145 
3,273 
3,398 

3,5i9 
3,633 


0 


,0338 


0,-27 


Days  |<iif. 


0,000 

0,1 5 1 
o,3o2 
0,453 
0,604 

0,754 
0,904 
i,o54 
1, 204 
1,353 

i,5o 

1,649 

1,797 

1,944 

2,089 

2,334 
3,378 

3,521 

2,663 
2,804 

3,943 
3,080 
3,3i5 
3,348 
3,478 

3,606 
3,739 
3,845 


83 


,036c 


0,28 


Days  I  dil'. 


0,00( 

0,1 54 
o,3o8 
0,461 
o,Ci  5 

0,768 
0,931 
1,074 
1,236 
1,378 

i,53o 
1,681 
1, 83 1 
1,981 

3,1  3o 

3,378 
2,425 
2,571 
2,716 

2,860 

3,oo3 
3,i44 
3,283 
3,420 
3,556 

3,688 
3,817 
3,942 
4,060 


,0392 


0,29 


0,782 
0,937 
1,093 
1,348 
i,4o3 

1,557 
1,71 1 
1,864 
2,017 
2,169 


,0421 


0,0000 
0,000 1 
0,0004 
0,0009 
0,001  () 

0,0025 

o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,01 2 1 
0,01 44 
0,0169 
0,0196 

0,0225 
o,o256 
0,0389 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
o,o484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 


c" 


[t  -\-  r")^  or  r-  ■ 


r"-   ticarly. 


Proportiooal  parts  for  the  Chord. 


113 

116 

120 

134 

128 

I  32 

1 36 

i4o 

144 

1 48 

l52 

1 56 

, 

II 

13 

12 

13 

i3 

i3 

i4 

i4 

i4 

i5 

i5 

16 

3 

22 

33 

24 

25 

26 

26 

27 

28 

29 

3o 

3o 

3i 

3 

34 

35 

36 

37 

38 

4o 

4i 

42 

43 

44 

4b 

47 

4 

45 

46 

48 

5o 

5i 

53 

54 

56 

58 

bq 

61 

63 

5 

56 

58 

60 

62 

64 

66 

68 

70 

72 

74 

7b 

78 

6 

67 

70 

72 

74 

77 

79 

83 

84 

86 

89 

^1 

94 

7 

78 

81 

84 

87 

90 

92 

qi 

9a 

1 01 

104 

106 

109 

8 

qo 

q3 

96 

99 

102 

106 

109 

112 

n5 

118 

122 

125 

9 

1 01 

io4 

108 

112 

ii5 

"9 

133 

126 

i3o 

1 33 

1 37 

i4o 

lu  the  first  approximation  we  shall  use  the  equations  (C)(jD),  computing 
the  numbers  to  one  or  two  places  of  decimals.  Now  if  we  suppose  ç  =  1.  these 
equations  become  (;2  =  0,26,  r2 -)-)-"2  =  10,2.  The  first  of  these  numbers  is  to  be 
found  ou  the  right  hand  side  of  Table  II.,  and  the  second  at  the  bottom,  the 
corresponding  value  of  T  is  nearly  31  days.  This  being  nearly  three  times  the 
actual  value  of  T,  we  may  take  for  g  one  third  part  of  the  value  first  assumed,  or 
g  =  J  ;  then  repeating  the  preceding  calculation,  with  one  more  decimal  in  c-, 
we  get  c2  =  0,067  ;  r2 +  r"2  =  3,53,  and  the  corresponding  value  of  T  is  about  124 
days  ;  so  that  we  must  decrease  e  a  little  more.  We  shall  therefore  take  for  the  first 
hypothesis  of  the  preceding  table  ç  =  0,3,  and  use  the  equations  (  jî  ),  (B),  (  C  ), 
making  the  c^ilculation  to  a  greater  degree  of  accuracy,  and  we  get  7"=  11,632. 
This  time  being  rather  too  small,  the  value  of  §  is  increased  j-Vi  '°  Hypothesis 
II.,  and  the  resulting  value  of  T  becomes  11,81-1.  Increasing  ç  by  2-50,  we  obtain 
in  a  third  hypothesis  7-=  11,837,  which  is  rather  too  large.  Finally  decreasing 
this  last  value  of  §  by  ^.jn  part,  we  obtain  ç  =  0,3085S,  and  T=  U''''^',S34,  and 
this  value  of  T  agrees  with  that  by  observation.  We  may  use  the  values  obtained 
by  this  last  o()eration,  as  being  very  near  the  true  values  so  that  we  shall  have 
g  =  0,30S58,  r=l,21-J12,  r"=l,38443,  c  =  0,23267  ;  which  are  almost  identically 
the  same  with  those  obtained  in  the  above  mentioned  work  of  Dr.  Olbers. 


Trop,  parts  for  lliu  sum  of  llio  Itailii 

■  I  3  I  3  I  4  I  5  I  6  I  7  I  8  I  9 


I 
1 

I 
3 

3 

3 

3 

3 

4 

4 

4 

5 

5 

6 

6 

6 

6 

7 

7 

8 

8 

'. 

8 

lO 

9 

10 

10 

1 1 

1 1 

I  3 

1 1 

i3 

13 

i4 

i3 

i4 

i3 

i5 

i4 

16 

i5 

17 

i5 

i8 

iG 

iS 

17 

19 

18 

20 

18 

31 

19 

22 

20 

23 

20 

23 

TABLE   II. 

This  gives  the  time  T  of  describing  a  parabolic  arc  by  a  comet,  the  sum  of  the  extreme  radii  ;■  -f- 1 
top,  and  the  cliord  c  at  the  left  side  of  the  page. 


being  found  at  the 


Sum  r,r  th"  liiuhi  r  H- r".                                                                                                            1 

Chord 
C. 

0,30 

0,31 

0,3-2 

0,33 

0,34 

0,35 

0,36 

0,37 

0,38 

0,39 

Days  |dif. 

Day»  |,lir. 

Davs  lilit: 

Days  |ilif. 

Days  |i!ir. 

Days  lilit'. 

Days  Idif. 

Days  |,lif. 

Days  Idif. 

Day»  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0«i 

_ 

0,0000 

0,01 

0,169 

3 

0,162 

2 

0,164 

3 

0,167 

2 

0,169 

3 

0,172 

2 

0,174 

3 

0,177 

2 

0,179 

3 

0,182 

2 

0,0001 

0,02 

o,3l8 

6 

0,324 

5 

0,329 

5 

0,334 

5 

0,339 

5 

0,344 

5 

0,349 

5 

0,354 

4 

0,358 

5 

0,363 

5 

o,ooo4 

o,o3 

0,477 

S 

0,485 

8 

0,493 

8 

o,5oi 

■  7 

o,5o8 

8 

o,5i6 

7 

o,523 

7 

o,53o 

7 

0,537 

7 

0,544 

7 

0,000g 

o,o4 

0,636 

1 1 

0,647 

10 

0,657 

10 

0,667 

II 

0,678 

9 

0,687 

10 

0,697 

10 

0,707 

9 

0,716 

:o 

0,726 

9 

0,0016 

o,o5 

o,7o5 

i3 

0,808 

i3 

0,821 

i3 

0,834 

i3 

0,847 

12 

0,859 

12 

0,871 

12 

0,883 

12 

0,895 

12 

0,907 

12 

0,0025 

o,o6 

0,954 

i5 

0,969 

16 

0,985 

i5 

1,000 

16 

1,016 

i4 

i,o3(' 

i5 

1 ,045 

i5 

1.060 

i4 

1,074 

i4 

1  ,oSS 

i4 

0,00  36 

0,07 

1,112 

iS 

i,i3o 

19 

i,i4g 

18 

1,167 

17 

1, 1 84 

18 

1,202 

17 

i,2ig 

17 

1,236 

16 

1,252 

17 

1 ,260 

16 

0,0049 

0,08 

1,270 

21 

1, 29 1 

21 

I,3l2 

20 

1,332 

21 

1 ,353 

30 

1,373 

19 

1,392 

20 

I,4l2 

19 

i,43i 

19 

1 ,45" 

iS 

0,0064 

0,09 

1,427 

24 

1, 45 1 

24 

1,475 

23 

1,498 

23 

1,521 

22 

1,543 

22 

1,565 

22 

1,587 

22 

i,6og 

21 

i,63o 

21 

0,0081 

0,10 

1,584 

27 

1 ,61 1 

26 

1,637 

26 

1,663 

26 

1,689 

25 

1,714 

24 

1,738 

25 

1,763 

24 

1,787 

23 

1,810 

23 

0,0100 

0,1 1 

1, 74 1 

3o 

1,771 

29 

1 ,800 

28 

1,828 

28 

1,856 

26 

1,884 

27 

1,91 1 

27 

1,938 

26 

1,964 

26 

1.990 

26 

0,0121 

0,12 

1,897 

33 

1,930 

3i 

1,961 

3i 

1,992 

3i 

2,023 

3o 

2,o53 

3o 

2,o83 

29 

2,112 

29 

2,l4l 

28 

2,169 

29 

0,0144 

0,1 3 

2,o53 

35 

2,088 

34 

2,122 

U 

2,1 56 

33 

2,189 

33 

2,222 

33 

2,255 

3i 

2,286 

32 

2,3i8 

3i 

2,34g 

3o 

0,0169 

0,1 4 

2,208 

38 

2,246 

37 

2,283 

36 

2,319 

36 

0,355 

36 

2,391 

35 

2,426 

M 

2,460 

34 

2,494 

33 

2,527 

33 

0,0196 

0,1 5 

2,362 

4i 

2,4o3 

40 

2,443 

39 

2,482 

39 

2,52  1 

38 

2,559 

37 

2,596 

37 

2,633 

37 

2,670 

35 

2,7o5 

36 

0,0225 

0,16 

2,5i5 

Âà 

2,559 

43 

2,602 

42 

2,644 

42 

2,686 

40 

2,726 

40 

2,766 

40 

2,806 

39 

2,845 

38 

2,883 

38 

o,0256 

0,17 

2,668 

4C 

2,714 

46 

2,760 

45 

2,8o5 

45 

2,85o 

43 

2,893 

43 

2,936 

42 

2,978 

42 

3,020 

4o 

3,06c 

4i 

0,0289 

0,18 

2,819 

5o 

2,860 

49 

2,918 

48 

2.966 

47 

3,01 3 

46 

3,059 

46 

3,io5 

45 

3,1 5o 

M 

3,194 

43 

3,237 

43 

o,o324 

0,19 

2,97c 

53 

3,023 

52 

3,075 

5i 

3,126 

49 

3,175 

5o 

3,225 

48 

3,273 

47 

3,320 

Al 

3,367 

46 

3,41 3 

45 

o,o36i 

0,20 

3,119 

56 

3,175 

55 

3,a3o 

54 

3,284 

53 

3,337 

52 

3,389 

5i 

3,440 

5o 

3,49" 

5o 

3,540 

48 

3,588 

48 

o,o4oo 

0,21 

3,26" 

60 

3,327 

58 

3,385 

57 

3,442 

56 

3,4g8 

55 

3,553 

54 

3,607 

53 

3,660 

52 

3,712 

5i 

3,763 

5i 

o,o44i 

0,22 

3,4i4 

63 

3,477 

61 

3,538 

60 

3,598 

59 

3.657 

58 

3,71 5 

57 

3,772 

56 

3,828 

55 

3,883 

54 

3,937 

53 

0,0484 

0,23 

3,559 

66 

3,625 

65 

3,690 

64 

3,754 

62 

3,816 

61 

3,877 

60 

3,937 

58 

3,995 

58 

4,o53 

57 

4,110 

56 

0,0629 

0,24 

3,702 

70 

3,772 

69 

3,84 1 

67 

3,908 

65 

3,970 

64 

4,o37 

63 

4,100 

62 

4,162 

60 

4,222 

60 

4,282 

59 

0,0576 

0,25 

3,844 

74 

3,918 

72 

3,990 

70 

4,060 

69 

4,129 

68 

4,197 

66 

4,263 

64 

4,327 

64 

4,3gi 

62 

4,453 

61 

0,0620 

0,26 

3,983 

78 

4,061 

76 

4,1 37 

74 

4,21 1 

73 

4,284 

70 

4,354 

70 

4,424 

67 

4.491 

67 

4.558 

65 

4,623 

64 

0,0676 

0,27 

4.11Q 

83 

4,202 

80 

4,28? 

79 

4,36 1 

76 

4,437 

74 

4,5ii 

72 

4,583 

71 

4.654 

70 

4,734 

68 

4,792 

67 

0,0729 

0,28 

4.252 

88 

4,340 

85 

4.425 

83 

4,5o8 

80 

4,588 

77 

4,665 

76 

4,74 1 

75 

4,816 

73 

4.S8g 

71 

4,960 

70 

0,0784 

0,29 

4,38 1 

95 

4,476 

90 

4,566 

86 

4,652 

84 

4,736 

82 

4,818 

80 

4,898 

78 

4,976 

76 

5,05; 

75 

5,127 

73 

0,0841 

o,3o 

4,5o3 

io3 

4,606 

97 

4,7o3 

91 

4,794 

89 

4,883 

86 

4,969 

84 

5,o53 

81 

5,1 34 

80 

5,2i4 

78 

5,2g2 

76 

0,0900 

0,3 1 

4,73o 

io5 

4,835 

98 

4,933 

94 

5,027 

90 

5,117 

88 

5,2o5 

85 

5,290 

84 

5,374 

81 

5,455 

80 

0,0961 

0,32 

4,961 

107 

5,068 

100 

5,1 68 

95 

5,263 

92 

5,355 

90 

5,445 

87 

5,532 

85 

5,617 

83 

0,1024 

0,33 

5,195 

109 

5.3o4 

102 

5,406 

97 

5.5o3 

94 

5,59-^ 

91 

5,688 

89 

5,777 

87 

0,1  o8g 

0,34 

5,433 

no 

5,543 

io4 

5,647 

99 

5,746 

96 

5,842 

93 

5,g35 

90 

0,1 1 56 

0,35 

5,674 

ii3 

5,787 

io5 

5.892 

101 

5,Qg3 

97 

6,090 

95 

0,1225 

o,36 

5,919 

ii4 

6,o33 

107 

6,1 4o 

io3 

6,243 

99 

0,1296 

0,37 

6,168 

ii5 

6,283 

log 

6,392 

104 

0,1 36g 

0,38 

6,419 

118 

6,537 

no 

0,1 444 

0,39 

6,674 

i'9 

0,1  52  1 

,0450 

,0481 

,0512 

,0545 

,0578 

,0613 

,0648 

,0685 

,0722 

,0761 

C2 

4  .  (r  +  r"i!i  or    T-  +  r"a    n.-iirly.                                                                                                           | 

p 

roport 

oiial  parts  for  the  Chord. 

122 

125 

128 

i3i 

1 34 

1 37 

i4o 

143 

146 

149 

l52 

i55 

i58 

161 

164 

167 

170 

173 

176 

17g 

182 

I 

12 

i3 

i3 

i3 

i3 

14 

i4 

i4 

i5 

l5 

x5 

16 

16 

16 

16 

17 

17 

17 

18 

18 

18 

2 

24 

25 

26 

26 

27 

27 

28 

29 

2g 

3o 

3o 

3i 

32 

32 

33 

33 

34 

35 

35 

36 

36 

3 

37 

38 

38 

3g 

40 

4i 

42 

43 

AA 

45 

46 

47 

47 

48 

49 

5o 

5i 

52 

53 

54 

55 

4 

4g 

5o 

5i 

52 

54 

55 

56 

57 

68 

60 

61 

62 

63 

64 

66 

67 

68 

6g 

70 

72 

73 

5 

61 

63 

64 

66 

67 

tig 

70 

72 

73 

75 

76 

78 

79 

81 

82 

84 

85 

87 

88 

go 

gi 

6 

73 

75 

77 

79 

80 

82 

84 

86 

88 

8g 

91 

93 

95 

97 

»? 

100 

102 

io4 

106 

107 

109 

7 

85 

88 

90 

92 

94 

96 

g8 

100 

102 

1 04 

106 

109 

n  1 

n3 

ii5 

117 

ng 

121 

123 

125 

127 

8 

08 

100 

102 

io5 

107 

no 

112 

ii4 

117 

ng 

122 

124 

126 

129 

i3i 

1 34 

1 36 

I  38 

i4i 

i43 

1 46 

9 

no 

ii3 

ii5 

118 

121 

123 

126 

12g 

i3i 

i34 

1 37 

i4o 

142 

145 

i48 

i5o 

1 53 

i56 

i58 

161 

164 

In  making  these  successive  operations,  it  is  convenient  to  vary  §,  by  some  aliquot  part  of  its  value,  represented  by  ,'.ç  ; 
f  being  an  intec:ral  number  ;  since  by  this  means  we  are  enabled  to  deduce  any  one  of  the  coefficients  of  §,  in  the  successive 
operations,  from  tliat  which  immediately  precedes  it  ;  as  in  the  small  tables  of  the  preceding  examj>lc.  Thus  if  we 
represent  by  A^  ,  ./7,  ,  ./Î,  ,  A^  ,  the  successive  vahiesof  the  term  0,87.3fi3ç  of  (he  equation  {A'),  we  shall  have,  when 
1  =  0,3,  .à,  :=  0,8736.3. ç=  0,26209,  in  the  first  operation.  In  the  second  hypothesis,  this  is  to  be  increased  by 
~.  .^,  =  0,00655  ;  by  which  means  it  becomes  A,  =  0,26*64.  In  the  third  hypothesis  this  is  increased,!-  .  jî,  =  0,00107; 
making  -5,  =  0,26971.  In  the  fourtli  hypothesis,  it  is  decreased  5555  .  A^  =  0,00013,  making  the  final  value  A^  =  0,26958  ; 
as  in  the  preceding  table.  In  like  manner  if  the  coefficient  of  g'-,  in  any  operation  be  represented  hy  A^  and  we  increase 
5  in  the  next  operation  by  the  quantity  ^.ç,  the  value  of  .^  will  become  A  .  {\ -\-%-\-};i)^=A-\-l  .A  ■\-Jy.B\  using 
for  brevity  B  =  l.A.  From  this  formula  we  obtain  the  successive  values  of  JÎ,  as  in  the  third  table  of  the  preceding 
e.\aniple.     In  this  way  we  obtain  the  values,  in  the  successive  operations,  with  very  little  additional  labor. 


TABLE  II. 

This  gives  tlie  time  T  of  ilesci-ihins;  a  par;ibolic  arc  by  a  comet,  (lie  sura  of  the  extreme  radii  r-j-r"  being  fomiJ   at  t)ie    top, 
nml  tlie  oboril  e  at  tin  U-lt  side  of  the  |iai;e. 


Sutii  ol"    the   llaiiii   r  -f-  ?'. 

Piop.  Jjarla  for  lliu  sum  ol*  tlie  Kadii. 
T  1  3  1  ,3  1  /i  1  5  1  6  1  7  1  8  1  0 

Cliord 

c. 

0,40 

0,41 

0,4-^ 

0,43 

0,44 

0,45 

0,46 

I 

2 

3 

0     0 
0     0 
0     I 

[ 
C 
I 
I 

0 

I 

1 
I 

2 

I      1  '  1       1  - 
1      I      1      I 

1  I      2     3 

2  2       3       3 

Duys  |.lif. 

Days  |.lif. 

Days  |,lif. 

Uays  |ilil'. 

Days  Iclil'. 

Days  |.lir. 

Days  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

o,ocx> 

0,000 

CJ,000(l 

0,01 

0,184 

2 

0,186 

2 

0,188 

3 

o,iqi 

2 

o,ig3 

2 

0,195 

2 

0,197 

2 

0,000 1 

4 

0     I 

I 

2 

2 

3334 

0,02 

o,368 

4 

0,372 

5 

0,37- 

4 

o,38i 

5 

o,386 

4 

0,390 

4 

0,394 

4 

0,0004 

o,o3 

0,55 1 

7 

0,558 

7 

o,565 

7 

0,572 

6 

0,578 

7 

o,585 

6 

o,5gi 

7 

o,ooog 

5 

1      I 

2 

2 

3 

3445 

o,o4 

0,735 

9 

0,744 

9 

0,753 

9 

0,762 

9 

0,771 

9 

0,780 

8 

0,788 

9 

0,0016 

6 

7 

I      I 
I      I 

3 
2 

2 
3 

3 

4 

4455 

4    5     6    6 

o,o5 

0,919 

II 

0,930 

II 

0,941 

II 

0,952 

1 1 

0,963 

1 1 

o,g74 

1 1 

o,g85 

II 

0,0035 

8 

J      2 

2 

3 

4 

5    (i    6    - 

0,06 

1,102 

i4 

1,116 

1 3 

i,i2g 

i4 

i,i43 

i3 

i,i56 

i3 

I, leg 

l3 

1,182 

i3 

o,oo36 

9 

I      2 

3 

4 

5 

5678 

0,07 

!  .385 

Hi 

i,3oi 

Hi 

1,3 1 - 

16 

1,333 

i5 

1,348 

i5 

1,363 

16 

1,37g 

i5 

o,oo4g 

5 
6 
6 

6789 

o,u8 

l,40h 

'9 

1,48- 

18 

i,5o5 

18 

1,533 

17 

1,540 

18 

1,558 

17 

1,575 

17 

0,0064 

10 

I      2 

3 
3 

4 

4 

o,og 

1,65 1 

21 

1 ,672 

20 

1,692 

20 

1,712 

20 

1,732 

20 

1,753 

19 

1,771 

20 

0,008 1 

1 1 

1 2 

I      2 
I      2 

4 
5 

789  10 
7     8  10  I  1 

0,10 

1,833 

23 

1,856 

23 

1,879 

23 

1,903 

33 

1,934 

22 

1,946 

21 

1,967 

22 

0,0100 

i3 

1     3 

1     3 

4 

5 

7 

8      9    10    13 

8  10  11  i3 

0,11 

2,0  [(> 

25 

2,o4l 

25 

2,o6(j 

25 

3,091 

24 

2,Il5 

24 

2,i3g 

24 

2,i63 

24 

0,0121 

i-i 

4 

6 

7 

0,12 
o,i3 

2 , 1  gS 
2,379 

27 
3o 

2,225 

2,4og 

28 

3o 

2,253 

2,43g 

27 
29 

3,380 
3,468 

26 
29 

2,3o6 
2,4g- 

27 
=9 

2,333 
2,526 

26 
28 

2,359 
2,554 

26 
28 

0,0 1 44 
0,0  i6g 

J  5 
i  6 

3     3 

2  3 

3  3 

5 
5 
5 

6 
6 

7 

8 

9  11   12  i4 
10  1 1  i3  i4 
10  12  i4  i5 

0,14 

2,56<> 

33 

2,593 

32 

2,625 

3. 

2,656 

32 

2,688 

3i 

2,719 

3o 

2,749 

3o 

0,0 1  g6 

17 

9 

o,i5 

2.741 

35 

2,7-6 

34 

2,810 

34 

2,844 

34 

2,8-8 

33 

2,911 

33 

2,g44 

33 

0,0225 

18 

2     4 
2     4 

5 
6 

7 
8 

9 

II  i3  i4  16 

11  i3  i5  17 

0,16 

3,921 

37 

3,958 

37 

3,gg5 

37 

3,o32 

35 

3,067 

36 

3,io3 

35 

3,i38 

35 

0,02  56 

19 

10 

0,17 

3,101 

3y 

3,i4o 

4o 

3,180 

38 

3,218 

3g 

3,257 

37 

3,2g4 

38 

3,332 

37 

0,0289 

20 

2     4 
2     4 
2     4 

6 

8 
8 

10 

12  14  16  18 
i3  i5  17  19 
i3  i5  18  20 

0,18 

3,280 

42 

3,323 

42 

3,364 

4i 

3,4o5 

4o 

3,445 

4i 

3,486 

39 

3,535 

39 

o,o334 

2 1 

6 

1 1 

0,19 

3,458 

45 

3,5o3 

44 

3,547 

44 

3,591 

43 

3,634 

42 

3,676 

42 

3,718 

4i 

o,o36i 

22 

7 

9 

1 1 

0,20 

3,636 

48 

3,684 

46 

3,73o 

46 

3,776 

45 

3,821 

45 

3,866 

44 

3,gio 

44 

o,o4oo 

23 

24 

3     5 
2     6 

7 
7 

9 
10 

1 2 
1 2 

i4  16  18  21 

l4    17    19    23 

0,21 

3,8 1 4 

49 

3,863 

49 

3,gi2 

49 

3,961 

48 

4,009 

47 

4,o56 

46 

4,102 

46 

o,o44i 

0,22 

3,ggo 

52 

4,042 

52 

4,094 

5i 

4,i45 

5o 

4,ic)5 

5o 

4,2.45 

49 

4,2g4 

48 

o,o484 

2  5 

3     5 

8 

10 

i3 

i5  18  20  23 

0,23 

4,166 

55 

4,221 

54 

4,275 

53 

4,328 

53 

4,38 1 

53 

4,433 

5i 

4,484 

5i 

o,o53g 

26 

3     5 

8 

10 

i3 

16  18  21   23 

0,24 

4,341 

5- 

4,3g8 

57 

4,455 

56 

4,5ii 

55 

4,566 

55 

4,631 

54 

4,675 

53 

0,0576 

27 

38 

3     5 
3     6 

8 
8 

1 1 
1 1 

i4 

14 

16  ig  22  24 

17  20  22  25 

0,25 

4,5i4 

61 

4,575 

5g 

4,634 

59 

4,693 

58 

4,75 1 

57 

4,So8 

56 

4,864 

55 

0,0635 

29 

3     6 

9 

12 

i5 

17  30  23  26 

0,26 

4.(i87 

64 

4,75 1 

63 

4,81 3 

6i 

4,874 

60 

4,934 

60 

4,gg4 

59 

5,o53 

58 

0,0676 

0,27 

4,859 

66 

4,g25 

65 

4,ggo 

64 

5,o54 

63 

5,117 

62 

5,17g 

62 

5,341 

60 

0,0739 

3o 

3     6 

9 

9 

10 

12 

i5 

18  21  24  27 

0,28 

5,o3o 

69 

5,09g 

68 

5,167 

66 

5,233 

66 

5,399 

65 

5,364 

64 

5,428 

63 

0,0784 

3i 

3     6 

12 

16 

19    32    25    28 

0,2g 

5,200 

72 

5,273 

70 

5,342 

70 

5,4i2 

68 

5,48o 

67 

5,547 

67 

5,6i4 

65 

0,084 1 

32 

3     6 

i3 

16 

19    22    26    29 

33 

3     7 

10 

i3 

17 

20  23  26  3o 

o,3o 

5.368 

75 

5,443 

73 

5,5i6 

73 

5,589 

71 

5,660 

70 

5,73o 

6g 

5,7gg 

68 

0,0900 

34 

3     7 

10 

i4 

17 

20  24  27  3 1 

o,3i 

5,535 

78 

5,6i3 

77 

5,690 

75 

5,765 

74 

5,839 

73 

5,gi3 

72 

5,984 

70 

0,0961 

0,32 

5,700 

81 

5,781 

80 

5.861 

79 

5,940 

77 

6,017 

75 

6,092 

75 

6,167 

73 

0,1024 

35 

4     7 

1 1 

i4 

18 

2  1    25    28    32 

0,33 

5,864 

84 

5,948 

83 

6,o3i 

82 

6,ii3 

80 

6,193 

79 

6,373 

77 

6,349 

76 

o,io8g 

36 

4    7 

1 1 

i4 

18 

32    25    39    32 

0,34 

6,025 

89 

6,1 14 

86 

6,200 

85 

6,285 

83 

6,368 

83 

6,45o 

80 

6,53o 

79 

0,11 56 

37 
38 

4    7 
4     8 

1 1 
1 1 

i5 
i5 

19 
19 

22  26  3o  33 
33  37  3o  34 

0,35 

6,i85 

9' 

6,277 

9° 

6,367 

88 

6,455 

87 

6,542 

84 

6,636 

84 

6,710 

82 

0,1225 

39 

4     8 

12 

16 

20 

23  27  3 1  35 

o,36 

6,343 

96 

6,438 

94 

6,533 

92 

6,624 

89 

6,7 1 3 

88 

6,801 

87 

6,888 

85 

0, 1 296 

24  28  32  36 

25  3g  33  37 

25  2g  34  38 

26  3o  34  3g 

0,3-7 

6,496 

lOI 

6,5g7 

98 

6,695 

95 

6,790 

94 

6,884 

9" 

6,975 

90 

7,o65 

88 

0,1369 

40 

4    8 

13 

16 

30 

o,38 

6,647 

106 

6,753 

102 

6,855 

100 

6,g55 

97 

7,o53 

95 

7,1 47 

93 

7,240 

91 

o,i444 

41 

4    8 

1  2 

16 

31 

0,39 

6,793 

112 

6,905 

108 

7,0 1 3 

1 04 

7,117 

lOI 

7,218 

99 

7,3i7 

96 

7,4 1 3 

95 

0,l52I 

42 
43 

4     8 
4     9 

i3 
i3 

17 
17 

21 
33 

o,4o 

6,933 

120 

7,o53 

ii4 

7, '67 

,09 

7,376 

106 

7,389 

102 

7,484 

101 

7,585 

9& 

0,1600 

44 

4    9 

i3 

18 

22 

26  3 1  35  4o 

0,4 1 

7,194 

123 

7,3i7 

ii5 

7,433 

no 

7,542 

108 

7.65o 

io4 

7,754 

102 

0,1681 

I    '■> 

18 
18 

23 
23 

27  32  36  4i 
38  33  37  4i 

28  33  38  42 
2g  34  38  43 

0,42 

7,45g 

124 

7,583 

1 17 

7,700 

112 

7,8 13 

log 

7,921 

106 

0,1764 

45 

1 4 

0,43 

7,727 

126 

7,853 

u8 

7,971 

ii4 

8,o85 

no 

0,1849 

46 

5    9 

i4 

0,44 

7,998 

127 

8,125 

120 

8,245 

ii5 

0,1936 

47 
48 

?     9 
J   ru 

14 
14 

19 
19 

24 
34 

0,45 

8,273 

12g 

8,4oi 

121 

0,2025 

49 

5o 
5i 

52 

5  10 

5  10 
J  10 
J   10 

i5 

i5 
i5 
16 

20 

20 
20 
21 

25 

25 
26 
26 

29  34  3g  44 

30  35  40  45 

3 1  36  4i  46 
3i  36  42  47 

,0800  1 

,0841 

,0882 

,0925  1 

,0968  1 

,101:3 

,1058  1 

C^ 

'                       1 

'           ] 

'                       1 

'                        1 

53 

J   1 1 

16 

31 

27 

32  37  42  48 

J 

J    .  (r    -f-  r')3  or  r^  +  r  ^  nenily.                                                                    | 

54 
55     ( 

J  1 1 
5  1 1 

16 

17 

22 
22 

27 
28 

32  38  43  4g 

33  39  A4  5o 

Proporlional  parts  fur  tlje  Ciionl. 

184 

i85 

i8( 

)    18- 

188 

i8g 

190 

19 

'9 

i       193 

ig4 

ig5 

'9 

^     197 

56     f 

3    I  1 

17 

23 

28 

34  3g  45  5o 



— 

— 

— 



— 

— 



— 



— 



57     ( 

Î    I  I 

■7 

23 

29 

34  4o  46  5 1 

I       18 

19 

IC 

■Ç 

)        19 

19 

19 

It 

)        i< 

)        19 

19 

20 

2( 

3             20 

58      ( 

)    12 

17 

23 

29 

35  4i  46  52 

2       37 

37 

3- 

3- 

38 

38 

38 

3{ 

i       3i 

S      39 

39 

39 

3( 

i            39 

59     f 

i    12 

18 

24 

3o 

35  4i  47  53 

3    55 

56 

se 

se 

)        56 

57 

57 

5- 

7       5f 

i        58 

58 

59 

5( 

)            59 

4    74 

74 

74 

7- 

75 

76 

76 

7( 

'         7' 

J        77 

78 

78 

7i 

i         79 

5    92 

93 

93 

9^ 

94 

95 

95 

9f 

>        9^ 

'        97 

97 

98 

9! 

5        99 

60     ( 

J    12 

18 

24 

3o 

36  43  48  54 

6  no 

III 

112 

1 15 

Ii3 

ii3 

:i4 

11; 

II 

)       116 

116 

117 

11! 

i      118 

70     - 

1    14 

31 

28 

35 

42  49  56  63 

7   "29 

i3o 

1 3c 

i3i 

1 32 

l32 

1 33 

i3< 

i3i 

i      i35 

1 36 

i37 

i3 

7      i38 

80     i 

.    16 

34 

32 

40 

48  56  64  72 

8  i47 

1 48 

i4ç 

1 5c 

i5o 

i5i 

1 52 

i5: 

1 5. 

i54 

1 55 

1 56 

i5 

7      t58 

90     ( 

i    18 

27  36 

45 

54  63  73  81 

Q  1 66 

16- 

16- 

iW 

16c, 

I-r 

i-i 

I—. 

I- 

J              174 

175 

176 

1-' 

i          177          1  C)0  1 1  ( 

1    30 

3<,  4o 

5o'6ol7.il8ol9o| 

A4 


TABLE 

II.- 

-To  find  the  lime  T 

;  the 

sum 

of  the 

rad 

ir+r 

",  and  the  chord  c  bein 

ge;iven. 

Sum  .if   tlH>  RaJii  r  -|-  r".                                                                                                                       1 

Chord 

0,47 

0,48 

0,49 

0,50 

0,51 

0,52 

0,53 

0,54 

0,55 

0,56 

Days  |dir. 

Days  |iUr. 

Days  |dil'. 

Days  |d>f. 

Days  |dir. 

Days  |dif. 

Days  |dir. 

Days  |dll'. 

Day»  [dif. 

llavs  \Aii. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

O.OOO 

0,000 

0,000 

0,000 

0,00C) 

0,0000 

0,01 

o>i99 

2 

0,201 

2 

o,3o3 

3 

0,206 

3 

0,208 

2 

0,210 

3 

0,312 

3 

0,3l4 

2 

0,3l6 

3 

0,3l8 

I 

0,0001 

0,02 

o,3g8 

5 

o,4o3 

4 

0,407 

4 

0,4 1  I 

4 

0,4 1 5 

4 

0,419 

4 

0,423 

4 

0,437 

4 

0,43  I 

4 

0,435 

4 

0,0004 

o,o3 

0,598 

6 

0,604 

6 

0,610 

6 

0,616 

7 

0,623 

6 

0,62g 

6 

o,635 

6 

0,64 1 

6 

0,647 

5 

0,652 

6 

o,ooog 

0,04 

0.797 

8 

o,8o5 

9 

0,8 1 4 

8 

0,822 

8 

o,83o 

8 

0,838 

8 

0,846 

8 

o,854 

8 

0,862 

8 

0,870 

8 

0,0016 

o,o5 

0,996 

10 

1,006 

II 

1,017 

10 

1,027 

10 

I,o37 

II 

i,o48 

10 

i,o58 

10 

1,068 

9 

1 ,077 

10 

1.087 

10 

0,0035  1 

0,06 

1,195 

12 

1,207 

i3 

1,230 

13 

1,233 

i3 

1,345 

13 

1,357 

13 

1,269 

13 

1,381 

13 

1,293 

11 

i,3o4 

13 

o,oo36 

0,07 

1,394 

i4 

i,4o8 

i5 

1,433 

i5 

1,438 

i4 

1,452 

i4 

1,466 

i4 

i,48o 

i4 

1,494 

14 

i,5o8 

i4 

1,522 

i3 

o,oo4g 

0,08 

1,592 

17 

i,6og 

17 

1 ,636 

16 

1,643 

17 

1,659 

16 

1,675 

16 

i,6gi 

16 

1,707 

16 

1,723 

i5 

1,738 

16 

0,0064 

o,og 

1=791 

'9 

1,810 

19 

1,83g 

18 

1,847 

19 

1,866 

18 

1,884 

18 

1,902 

18 

1,920 

18 

1,938 

17 

1,955 

iS 

0,0081 

0,10 

1.989 

21 

2,010 

31 

3,o3i 

21 

2,o52 

20 

2,072 

21 

3,og3 

30 

2,Il3 

30 

2,i33 

20 

2,i53 

19 

2,173 

20 

0,0100 

0,1 1 

2,187 

33 

2,210 

33 

2,233 

23 

3,356 

33 

2.279 

22 

2,3oi 

33 

2,333 

33 

2,345 

23 

3,367 

22 

3,38g 

31 

0,01  3  I 

0,12 

2,385 

25 

2,4lO 

25 

2,435 

25 

2,460 

25 

3,485 

25 

3,5l0 

24 

3.534 

34 

3,558 

34 

2,583 

33 

3,6o5 

33 

0,01 44 

o,i3 

2,582 

28 

2, 610 

27 

2,637 

27 

3,664 

27 

2,691 

27 

3,718 

26 

3,744 

26 

2,770 

36 

2,796 

35 

3,821 

26 

0,01 6g 

o,i4 

2,779 

3o 

2,809 

3o 

2,839 

29 

2,868 

29 

2.897 

28 

2,g25 

29 

2,954 

28 

3,983 

38 

3,010 

27 

3,037 

27 

0,01  g6 

0,1 5 

3,976 

33 

3,008 

33 

3,o4o 

3i 

3,071 

3i 

3,102 

3i 

3,i33 

3o 

3,i63 

3o 

3,193 

3o 

3,333 

3o 

3,253 

29 

0,0335 

0,16 

3,173 

34 

3,207 

34 

3,241 

33 

3,374 

33 

3,3o7 

33 

3,340 

33 

3,373 

32 

3,4o5 

33 

3,437 

3i 

3,468 

3, 

o,o256 

0,17 

3,369 

36 

3,4o5 

36 

3,44i 

36 

3,477 

35 

3,5i2 

35 

3,547 

35 

3,582 

34 

3,616 

34 

3,65o 

33 

3,683 

33 

0,028g 

0,18 

3,564 

39 

3.6o3 

38 

3,64i 

38 

3,679 

37 

3,716 

38 

3,754 

36 

3,7QO 

36 

3,836 

36 

3,863 

36 

3,898 

37 

o,o324 

0,19 

3,759 

4i 

3,800 

4i 

3,841 

40 

3,881 

39 

3.920 

40 

3,g6o 

38 

3.998 

39 

4.037 

38 

4,075 

37 

4,112 

38 

o,o36i 

0,20 

3,954 

43 

3,gg7 

43 

4,o4o 

42 

4,083 

42 

4,124 

4i 

4,i65 

4i 

4.206 

4i 

4.347 

4o 

4,287 

4o 

4,337 

39 

o,o4oo 

0,21 

4,i48 

46 

4,ig4 

45 

4,339 

44 

4,283 

44 

4,337 

44 

4,37! 

43 

4,4 1 4 

42 

4.456 

42 

4,498 

42 

4,540 

42 

0,044 1 

0,22 

4,342 

48 

4,3go 

47 

4,437 

4l 

4,484 

46 

4,53o 

46 

4,576 

45 

4,621 

44 

4,665 

45 

4,710 

44 

4,754 

43 

o,o484 

0,23 

4,535 

5o 

4,585 

5o 

4.635 

49 

4,684 

48 

4,733 

48 

4,780 

47 

4,827 

4i 

4,8-4 

46 

4.920 

46 

4,966 

46 

o,o52g 

0,24 

4,728 

52 

4,780 

53 

4,832 

5i 

4,883 

5i 

4,934 

5o 

4.984 

49 

5,o33 

49 

5,083 

49 

5,1 3i 

48 

5,179 

47 

0,0576 

0,25 

4,919 

55 

4,974 

54 

5,028 

54 

5,082 

53 

5,i35 

52 

5,187 

52 

5,33g 

5i 

5,290 

5i 

5,341 

5o 

5,391 

49 

0,0625 

0,26 

5,111 

57 

5,168 

56 

5.234 

56 

5,280 

55 

5,335 

55 

5,390 

54 

5,444 

53 

5,4g7 

53 

5,55o 

53 

5,603 

52 

0,0676 

0,27 

5,3oi 

60 

5,36i 

59 

5,420 

58 

5,478 

57 

5,535 

57 

5,592 

56 

5,648 

56 

5,704 

55 

5,759 

54 

5,8i3 

54 

0,072g 

0,28 

5,491 

62 

5,553 

61 

5,614 

61 

5,675 

59 

5,734 

60 

5,794 

58 

5,852 

58 

5,gio 

57 

5,967 

57 

6,034 

56 

0,0784 

0,29 

5,679 

65 

5,744 

64 

5,808 

63 

5,871 

62 

5,933 

61 

5,994 

61 

6,o55 

60 

6,ii5 

60 

6,175 

58 

6,233 

59 

0,084 1 

o,3o 

5,867 

67 

5,g34 

67 

6,001 

65 

6,066 

65 

6,i3i 

64 

6.195 

63 

6,258 

62 

6,320 

62 

6,382 

61 

6,443 

60 

o,ogoo 

o,3i 

6,o54 

70 

6,124 

69 

6,ig3 

68 

6,261 

67 

6,328 

66 

6,394 

65 

6,45g 

65 

6,524 

64 

6,588 

63 

6,65 1 

63 

o,og6i 

0,32 

6,240 

73 

6,3 1 3 

71 

6,384 

70 

6,454 

70 

6,534 

69 

6,593 

67 

6,660 

67 

6,727 

67 

6,794 

65 

6,859 

65 

0,1024 

0,33 

6,425 

75 

6,5oo 

74 

6,574 

73 

6,647 

73 

6,719 

71 

6,790 

70 

6,860 

70 

6,g3o 

68 

6,gg8 

68 

7,o6(5 

67 

0,1  o8g 

0,34 

6,6og 

78 

6,687 

76 

6,763 

7fi 

6,8  3g 

75 

6,914 

73 

6,987 

73 

7,060 

72 

7,i3s 

71 

7,2o3 

70 

7,373 

69 

0,1 1 56 

0,35 

6,792 

80 

6,872 

80 

6,952 

78 

7,o3o 

77 

7,107 

76 

7.183 

75 

7,258 

74 

7,332 

74 

7.406 

72 

7.478 

72 

0,1225 

o,36 

6,973 

83 

7,o56 

83 

7,139 

81 

7,220 

79 

7.299 

79 

7,378 

78 

7.456 

76 

7.532 

76 

7,608 

75 

7.683 

74 

0,1296 

0,37 

7.153 

86 

7,23g 

85 

7,334 

84 

7,408 

83 

7.491 

81 

7,572 

80 

7,652 

80 

7.733 

78 

7,810 

77 

7,887 

76 

0,1369 

0,38 

7,33i 

9" 

7.421 

88 

7,5og 

86 

7,595 

86 

7.681 

84 

7,765 

83 

7,848 

82 

7,930 

80 

8,010 

80 

8,ogo 

79 

0.1444 

o,3g 

7,5o8 

93 

7.601 

91 

7,693 

89 

7.781 

89 

7,870 

87 

7.957 

85 

8,042 

85 

8,127 

83 

8,310 

83 

8,2g2 

81 

0,1  521 

o,4o 

7,683 

96 

7.779 

94 

7,873 

93 

7.966 

91 

8,o57 

90 

8.147 

88 

8,335 

87 

8,333 

86 

8,4o8 

85 

8,493 

84 

0,1600 

o,4i 

7.856 

99 

7,955 

98 

8,o53 

96 

8,149 

94 

8,243 

g3 

8,336 

9' 

8,427 

90 

8,5i7 

89 

8,606 

87 

8,693 

86 

0,1681 

0,42 

8,027 

io3 

8,i3o 

lOI 

8,33i 

99 

8,33o 

98 

8,428 

96 

8,534 

94 

8,618 

93 

8,711 

91 

8,803 

90 

8,893 

89 

0,1764 

0,43 

8,.g5 

107 

8,3o3 

io5 

8,407 

io3 

8,5 10 

lOI 

8,611 

99 

8,710 

97 

8,807 

06 

8,903 

94 

8,9g7 

g3 

9.090 

91 

o,i84g 

0,44 

8,36o 

112 

8,472 

log 

8,58i 

107 

8,688 

io4 

8,792 

103 

8,8g4 

100 

8,994 

99 

9.093 

97 

9.190 

96 

9,386 

94 

o,ig36 

0,45 

8,522 

117 

8,63g 

Ii3 

8,753 

III 

8,863 

108 

8.971 

106 

9.077 

io3 

g,i8o 

102 

9.283 

100 

g,382 

99 

9,481 

97 

0,2025 

o,5o 

9,689 

1 36 

9.825 

13g 

9.954 

124 

10,078 

120 

io,ig8 

118 

io,3i6 

ii5 

10,43 1 

ii3 

0,3  5oo 

0,55 

11,178 

143 

11,331 

136 

o,3o35 

,1105 

,1152 

,1201 

,1250 

,1301 

,1352 

,1405 

,1458 

,1513  1  ,1568 

r^ 

i    .  (r  +  r'\'-  or    r~-  +  r  ^    nearly.                                                                                                           | 

163 

164 

166 

I 

16 

16 

17 

2 

32 

33 

33 

3 

4P 

49 

5o 

4 

65 

66 

66 

5 

81 

82 

83 

6 

97 

q8 

■  100 

7 

ii3 

ii5 

116 

8 

i3o 

i3i 

1 33 

9 

1 46 

1 48 

i4g 

168 

170 

172 

174 

176 

178 

180 

182 

184 

186 

1 88 

190 

192 

194 

1 96 

,98 

200 

303 

17 

'7 

17 

17 

18 

18 

18 

18 

18 

19 

ig 

ig 

19 

19 

20 

20 

20 

20 

34 

34 

34 

35 

35 

36 

36 

36 

37 

37 

38 

38 

38 

3q 

39 

40 

40 

40 

5o 

5i 

52 

52 

53 

53 

54 

55 

55 

56 

56 

57 

58 

58 

5q 

5q 

60 

61 

67 

68 

69 

70 

70 

71 

72 

73 

74 

74 

75 

76 

77 

78 

78 

79 

80 

81 

84 

85 

86 

87 

88 

89 

90 

9' 

92 

93 

94 

95 

96 

97 

9« 

99 

100 

lOI 

101 

102 

io3 

104 

106 

107 

108 

109 

no 

112 

ii3 

ii4 

Hi 

116 

118 

iiq 

120 

121 

118 

iiq 

120 

122 

123 

125 

136 

137 

12g 

i3o 

l32 

i33 

i34 

1 36 

l37 

.3q 

i4o 

l4l 

1 34 

1 36 

i38 

i3q 

i4i 

l42 

i44 

1 46 

147 

i4g 

i5o 

l52 

1 54 

i55 

.57 

1 58 

160 

1 6a 

i5i 

1 53 

i55 

1 57 

1 58 

160 

162 

1 64 

166 

167 

169 

171 

173 

175 

176 

178 

180 

183 

TABLE  II.  — To  find  tlie  time  T\  the  sum  of  the  radii  r-\-r\  and  Ihc  choi-d  <•  being  given. 


Siinioftlie  Kadii  r-\-r". 

1 

'rup 

pa, 

ij  II 

r  til 

,  Ml, 

1  ol 

llir 

{ml, 

~1 

Chonl 

c. 

0,57 

0,58 

0,59 

0,60 

0,61 

0,62 

'|2|J|4|5|6|7|8|9| 

1 

3 

3 

0 
0 

0 

0 
0 
I 

0 

I 
I 

0 

I 
1 

I 

I 
2 

I 

I 

2 

I 
I 
2 

I 
2 
2 

I 
2 
3 

Diijs  |.lil'. 

jiiiys  i.i.r. 

Uiiys  |.lir. 

U.iys  Idif. 

Uiiys  |.lir. 

Days  IlIIi". 

0,00 

0,O^KT 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,2  iq 

2 

0,221 

2 

0,223 

2 

0,225 

2 

0,227 

3 

0,239 

2 

0,000 1 

4 

0 

1 

1 

2 

2 

2 

3 

3 

4 

0,05 

o,43cj 

4 

0,443 

4 

0,447 

3 

o,45o 

4 

0,454 

4 

o,458 

3 

0,0004 

<),o3 

o,65b 

6 

o,6()4 

6 

0,670 

5 

0,675 

6 

0,681 

6 

0,687 

5 

O.OOOC) 

5 

1 

1 

2 

3 

3 

3 

4 

4 

5 

0,04 

0,878 

7 

0,885 

8 

0,893 

' 

0,900 

8 

0,908 

7 

0,915 

8 

0,0016 

() 

1 
1 

1 

1 

2 

3 

2 
3 

3 
4 

4 
4 

4 
5 

5 
6 

5 
6 

o,o5 

1.097 

9 

1,106 

10 

1,116 

9 

1,125 

10 

i,i35 

9 

1.144 

9 

0,0025 

8 

1 

3 

2 

3 

4 

5 

6 

6 

7 

0,06 

1,3 16 

12 

1,328 

II 

1,339 

II 

i,35o 

12 

1,362 

1 1 

1,373 

1 1 

o,oo36 

9 

1 

3 

3 

4 

5 

5 

6 

7 

8 

0,07 

1,535 

i4 

1, 54c. 

i3 

1 ,562 

i3 

1,575 

i3 

1,588 

i3 

1 ,60 1 

i3 

0,0049 
0,0064 

0,08 

■  .-54 

i5 

1 ,769 

16 

1,785 

i5 

1,800 

i5 

i,8i5 

i5 

i,83u 

i4 

10 

1 

2 

3 
3 
4 

4 

5 

6 

7 

8 

9 

0,09 

1.97J 

17 

1,990 

17 

2,007 

17 

2,024 

17 

2,o4l 

17 

2,o58 

17 

0,008 1 

1 1 
12 

1 
I 

2 
3 

4 
5 

6 
6 

7 
7 

8 
8 

9 
10 

10 
II 

0,10 

2,192 

'9 

2,211 

19 

2,23o 

19 

2,249 

19 

2,268 

18 

2,386 

'9 

0,0100 

i3 

1 

3 
3 

4 
4 

5 
6 

7 

8 
8 

9 

10 

12 
i3 

0,1  I 

2,410 

21 

2,43i 

21 

2,452 

21 

2,473 

21 

2,4cj4 

20 

2,5i4 

21 

0,01 3 1 

1 4 

I 

7 

10 

II 

0,12 

2,628 

24 

2,652 

23 

2,674 

23 

2,697 

23 

2,720 

22 

2,743 

22 

0,01 44 

i5 

2 

3 

5 

6 

g 

9 

10 

1 1 

12 
i3 

i4 

0,1 3 

2,847 

25 

2,872 

24 

2,896 

25 

2,921 

25 

2,946 

34 

2,970 

24 

0,0169 

16 

2 

3 

5 

6 

8 

II 

i4 

o,i4 

3,064 

27 

3,091 

27 

3,118 

27 

3,i45 

26 

3,171 

36 

3,197 

26 

0,0196 

17 

2 

3 

5 

7 

9 
9 

10 

10 

12 

14 

i5 

0,1 5 

3,282 

'9 

3,3 11 

'9 

3,340 

28 

3,368 

=9 

3,397 

28 

3,425 

27 

0,0225 

18 
'9 

2 
2 

4 
4 

5 
6 

7 
8 

II 

i3 
i3 

i4 
i5 

16 

17 

0,16 

3,490 

3i 

3,53o 

3i 

3,56i 

3i 

3,593 

3o 

3,622 

3o 

3,652 

'9 

o,o256 

0,17 

3,716 

33 

3,749 

33 

3,782 

32 

3,814 

33 

3,847 

3i 

3,878 

32 

0,0289 
o,o324 

20 

2 

4 

6 

8 

10 

12 

i4 

16 

18 

0,18 

3,933 

35 

3,968 

35 

4,oo3 

34 

4,o37 

34 

4,071 

34 

4,io5 

33 

21 

2 

4 

6 

8 

1 1 

1 3 

i5 

17 

■9 

0,19 

4,1 5o 

37 

4,"i87 

36 

4,223 

37 

4,260 

36 

4,296 

35 

4,33i 

36 

o,o36i 

23 
23 

2 
2 

4 

5 

7 

7 

9 
9 

II 
12 

i3 
i4 

i5 
16 

18 
18 

20 
21 

0,20 

4.366 

39 

4,4o5 

36 

4,443 

39 

4,482 

38 

4,520 

37 

4,557 

37 

o,o4oo 

24 

2 

5 

7 

10 

13 

i4 

17 

19 

22 

0,21 

4,582 

4i 

4,623 

4o 

4,663 

40 

4,7o3 

4o 

4,743 

4o 

4,783 

39 

0,044 1 

0,23 

4,797 

43 

4,84o 

43 

4,883 

42 

4,925 

42 

4,967 

4i 

5,008 

4i 

0,0484 

25 

3 

5 

8 

10 

i3 

i5 

18 

20 

23 

0,23 

5,012 

45 

5,o57 

45 

5,102 

ÂA 

5,i46 

A4 

5,190 

43 

5,233 

43 

0,0529 
0,0576 

36 

3 

5 

8 

10 

i3 

16 

18 

21 

23 

0,24 

5,226 

47 

5,273 

47 

5,320 

46 

5,366 

46 

5,4 1 2 

46 

5,458 

AA 

27 

28 

3 
3 

5 
6 

8 
8 

II 
II 

i4 
i4 

i6 
17 

19 
20 

22 
23 

24 

25 

0,25 

5,440 

5o 

5,490 

48 

5,538 

49 

5,587 

47 

5,634 

48 

5,682 

47 

0,0625 

29 

3 

6 

9 

12 

i5 

17 

20 

33 

26 

0,26 

5,654 

5i 

5,7o5 

5i 

5,756 

5o 

5,806 

5o 

5,856 

49 

5,905 

4q 

0,0676 
0,0729 
0,0784 
0,084 1 

3o 
3i 

32 

33 

3 
3 
3 
3 

6 
6 
6 

7 

i5 
16 

18 

0,27 

5,867 

53 

5,920 

53 

5,973 

53 

6,026 

5i 

6,077 

5? 

6,129 

5i 

9 

13 

21 

34 
35 

27 

28 

0,28 

6,080 

55 

6,1 35 

55 

6,190 

54 

6,244 

54 

6,298 

54 

6,352 

52 

9 

13 

19 

22 

0,29 

6,393 

57 

6,349 

57 

6,4o6 

57 

6,463 

56 

6,519 

55 

6,574 

55 

10 

lO 

l3 

i3 

16 

17 

19 
20 

22 

23 

36 
36 

'9 
3o 

o,3o 

6,5o3 

60 

6,563 

59 

6,623 

58 

6,680 

58 

6,738 

58 

6,796 

57 

0,0900 
0,0961 

34 

3 

7 

10 

i4 

17 

20 

24 

27 

3i 

0,3 1 

6,714 

62 

6,776 

61 

6,837 

61 

6,898 

60 

6,958 

59 

7,017 

59 

35 

4 

7 
7 

7 

1 1 

i4 

18 

21 

25 

28 

32 

0,32 

6,924 

64 

6,988 

63 

7,o5i 

63 

7,ii4 

62 

7,176 

62 

7,238 

61 

0,1024 

36 

4 

I  [ 

i4 
i5 

18 

23 

25 

Jo 

32 

0,33 

7,i33 

67 

7,200 

65 

7,365 

65 

7,33o 

64 

7,394 

64 

7,458 

63 

0,1089 

37 
38 

4 

1 1 

19 
ig 

32 

26 

33 

0,34 

7,342 

68 

7,4io 

68 

7,478 

67 

7,545 

67 

7,612 

66 

7,678 

65 

0,1 1 56 

4 

1 

8 

11 

i5 

23 

27 

3o 

34 

0,35 

7.55o 

71 

7,621 

70 

7,691 

69 

7,760 

69 

7,829 

68 

7,897 

67 

0,1235 

39 

4 

8 

12 

16 

30 

23 

27 

3i 

35 

o,36 

7,757 

73 

7,83o 

73 

7,903 

71 

7,974 

71 

8,045 

70 

8,ii5 

69 

0,1396 

4o 

4 

8 

12 

16 

20 

24 

28 

32 

36 

0,37 

7.963 

76 

8,039 

74 

8,ii3 

74 

8,187 

73 

8,260 

73 

8,333 

71 

0,1 369 

4i 

4 

8 

12 

16 

21 

25 

29 

33 

37 

o,38 

8,i6() 

78 

8,247 

77 

8,334 

76 

8,400 

75 

8,475 

75 

8,55o 

73 

o,i444 

42 

4 

8 

i3 

17 

21 

25 

29 

34 

38 

0,39 

8,373 

81 

8,45^ 

79 

8,533 

78 

8,611 

78 

8,68g 

77 

8,766 

76 

0,l52I 

43 
AA 

4 
4 

9 
9 

i3 
i3 

17 
18 

22 
22 

26 
26 

3o 
3i 

34 
35 

39 
4o 

o,4o 

8,577 

83 

8,660 

81 

8,74 1 

81 

8,823 

80 

8,902 

79 

8,981 

78 

0,1600 

0,41 

8,779 

86 

8,865 

84 

8,949 

83 

g,o33 

83 

9,114 

83 

9,196 

80 

0,1681 

45 

5 

9 

i4 

18 

33 

2-7 

32 

36 

4i 

0,42 

8,981 

88 

9,069 

86 

9, 1 55 

86 

g,24i 

85 

9,326 

83 

9,409 

83 

0,1764 

46 

5 

9 

i4 

18 

23 

28 

32 

37 

4i 

0,43 

9,181 

9' 

9,272 

89 

9,36i 

88 

9,449 

87 

9,536 

86 

9,633 

85 

0,1849 

47 

5 

9 

i4 

■9 

24 

28 

33 

38 

42 

0,44 

9,38o 

93 

9.473 

92 

9,565 

91 

9,656 

89 

9,745 

89 

9,834 

87 

0,1936 

48 
49 

5 
5 

10 
10 

i4 
i5 

19 
30 

24 

3  5 

29 
29 

34 
34 

38 
39 

43 
AA 

0,45 

9,578 

96 

9,674 

94 

9,768 

94 

9,863 

92 

9,954 

91 

10,045 

89 

0,2025 

i5 

3o 

45 
46 
47 
48 

o,5o 

to,544 

III 

,o,655 

109 

10,764 

107 

10,871 

106 

0,977 

io4 

1 1 ,08 1 

io3 

o,25oo 

5o 

5 

10 

20 

25 

35 

40 

0,55 

■1,45- 

i3i 

,1,588 

127 

Ii,7i5 

125 

ii,84o 

122 

1 ,96.1 

120 

12,082 

118 

o,3o35 

5i 

5 

10 

i5 

20 

26 

3i 

36 

4i 

0,60 

13,736 

i5o 

2,886 

i43 

1 3,029 

137 

o,36oo 

52 

53 

5 
5 

10 

16 
16 

31 
21 

36 

27 

3i 

32 

36 

37 

42 

42 

54 

5 

II 

16 

22 

27 

32 

38 

43 

49 

55 

6 

II 

17 

22 

28 

33 

39 

AA 

5o 

56 

6 

1 1 

17 

2  3 

28 

34 

39 

45 

5o 

57 

6 

u 

17 

33 

29 

34 

4o 

46 

5i 

58 

6 

13 

■7 

3  3 

29 

35 

4i 

46 

52 

59 

6 

13 

18 

34 

3o 

35 

4i 

47 

53 

60 
61 

6 
6 

13 
12 

18 
18 

24 
24 

3o 
3i 

36 

42 

43 

48 
49 

54 
55 

,16-25 

.1682  1 

.1741  1 

,1800  1 

,1861 

.1922 

â 

63 
63 
64 

(i 

■9 
19 
'9 

25 

3i 

37 
38 
38 

43 
AA 
45 

5o 
5o 
5i 

56 

^  .  {r  -t-  r")^  or  T^   -f-  r'"^   nearly. 

6 
6 

l3 

i3 

25 

26 

32 

32 

^8^ 

204 

206 

208 

210 

212 

214 

2lt 

1        2I« 

22 

0  22 

2  224 

22 

6  228 

2J0 



— 



— 



— 



— 

_  — 

.  — 

_ 



65 

7 

i3 

20 

26 

33 

39 

46 

53 

% 

I   20 

21 

21 

21 

21 

21 

2 

!     22 

2 

2   2 

2   22 

2 

3   23 

23 

66 

7 

i3 

20 

26 

33 

4o 

Aft 

53 

59 

2  4i 

4i 

42 

42 

42 

43 

A- 

i    ÂA 

4 

4   4 

i       45 

4 

5   46 

46 

67 

7 

i3 

20 

27 

34 

4o 

Ai 

54 

66 

3  61 

62 

62 

63 

64 

64 

6; 

)   65 

6 

6   6 

7   67 

6 

8   68 

69 

68 

7 

i4 

20 

27 

34 

4i 

48 

54 

61 

4  82 

82 

83 

84 

85 

86 

8f 

'   87 

8 

8   8( 

J   90 

9 

0   91 

92 

('9 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

5  102 

io3 

104 

io5 

1 06 

107 

I  of 

109 

II 

0  11 

112 

II 

3  ii4 

ii5 

6  122 

124 

125 

126 

127 

128 

1 3c 

i3i 

i3 

2   i3. 

i   i34 

i3 

fi  i37 

1 38 

70 

7 

i4 

21 

28 

35 

42 

49 

56 

63 

7  i43 

1 44 

1 46 

1 47 

1 48 

i5o 

i5i 

1 53 

i5 

4  15; 

)   l57 

i5 

8  160 

161 

80 

8 

16 

24 

32 

4o 

48 

56 

64 

72 

8  i63 

1 65 

166 

168 

170 

171 

17; 

174 

17 

5   17? 

179 

18 

1   182 

1 84 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

9  i84 

i85 

18- 

189 

191 

193 

19^ 

196 

'g' 

S  20c 

203 

20 

3  2o5 

307 

100 

10 

30 

3o 

4o 

5o 

60 

70 

80 

90 

TABLE  II. 

—  To  fiml  (he  time  T 

the  sum  0 

fttie  i-i 

A\\  J 

+  '■", 

and 

the  cliord  c 

beinp: 

given. 

Sum  ol' tlic  milii  r-^r",                                                                                                                 1 

Chord 

c. 

0,63 

0,64 

0,65 

0,66 

0,67 

0,68 

0,69 

0,70 

0,71 

0,72 

Days  |.lif. 

Diiys  |dir. 

Days  |.liC. 

Da)S  lilif. 

Days  |rlil'. 

Days  |ilil'. 

Dasy  |dif. 

Days  Idir. 

Days  |dil'. 

Days  l<lif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,0 1 

o,23l 

2 

0,233 

I 

0,234 

2 

o,336 

2 

o,238 

2 

0,240 

1 

0,241 

2 

0,243 

2 

0,245 

2 

0,247 

1 

0,0001 

0,03 

0,46 1 

4 

0,465 

4 

0,469 

3 

0,472 

4 

0,476 

3 

0,479 

4 

0,483 

3 

0,486 

4 

o,4go 

3 

0,493 

4 

0,0004 

o,o3 

0,692 

6 

0,698 

5 

0,703 

5 

0,708 

6 

0,714 

5 

0,719 

5 

0,724 

6 

o,73o 

5 

0,735 

5 

0,740 

5 

o,ooog 

o,o4 

0,923 

7 

0,930 

7 

0,937 

7 

0,944 

8 

0,952 

7 

0,959 

7 

0,966 

7 

0,973 

7 

0,980 

6 

0,986 

7 

0,0016 

o,o5 

i,i53 

9 

1,162 

9 

1,171 

9 

1,18c. 

9 

1,189 

9 

1,198 

9 

1,207 

9 

1,216 

8 

1,224 

9 

1,233 

8 

0,0025 

0,06 

1,384 

II 

1,395 

1 1 

1, 406 

10 

i,4i6 

11 

1,427 

11 

1,438 

10 

1,448 

1 1 

1,459 

10 

1,469 

10 

1,479 

1 1 

o,oo36 

0,07 

1, 61 4 

i3 

1,627 

i3 

1 ,64( 

12 

1,652 

i3 

1,665 

12 

1,677 

12 

1,689 

i3 

1,702 

12 

1,714 

12 

1,72(1 

12 

0,0049 

o,oS 

1,844 

i5 

1,869 

i5 

1,874 

i4 

1,888 

14 

1,902 

i4 

1.916 

i4 

i,g3t 

i4 

1,944 

14 

1,958 

i4 

1,973 

i4 

0,0064 

0,09 

2,075 

16 

2 ,09  i 

16 

2,107 

17 

2,124 

16 

2,i4o 

16 

2,i56 

i5 

2,171 

16 

2,187 

16 

2,203 

i5 

2,218 

16 

0,0081 

0,10 

3,3o5 

18 

2,323 

18 

2,341 

18 

2,359 

18 

2,377 

18 

2,395 

17 

2,4l2 

18 

2,43o 

17 

2,447 

17 

2,464 

17 

0,0100 

0,1 1 

2,535 

20 

2,555 

20 

2,575 

19 

2,5g4 

20 

2,614 

20 

2,634 

19 

2,653 

19 

2,672 

19 

2.6gi 

19 

2,710 

'9 

0,01 2 1 

0,12 

2,764 

22 

2,786 

22 

2,80b 

22 

2,83o 

21 

2,85i 

21 

2,872 

22 

2,894 

21 

2,915 

20 

2,935 

21 

2,956 

21 

o,oi44 

0,1 3 

2.oq4 

24 

3,018 

23 

3,04 1 

24 

3,o65 

23 

3,088 

23 

3,111 

23 

3,i34 

23 

3,1 57 

22 

3,179 

23 

3,202 

22 

(J  ,01 69 

o,i4 

3,223 

26 

3,249 

25 

3,274 

26 

o,3oo 

25 

3,325 

25 

3,35g 

24 

3,37/ 

25 

3,399 

24 

3,423 

24 

3,447 

24 

0,0196 

0,1 5 

3,452 

28 

3,480 

27 

3,5o7 

27 

3,534 

27 

3,56i 

27 

3,588 

26 

3,6i4 

27 

3,64i 

26 

3,667 

26 

3,693 

26 

0,0225 

0,16 

3,681 

3o 

3,71 1 

29 

3,740 

^9 

3,769 

29 

3,798 

28 

3,826 

28 

3,854 

28 

3,882 

28 

3,gio 

28 

3,938 

27 

o,0256 

0,17 

3,910 

3i 

3,941 

3i 

3,972 

3i 

4,oo3 

3i 

4,o34 

3o 

4,064 

3o 

4,094 

3o 

4,124 

3o 

4,1 54 

29 

4,i83 

29 

0,0289 

0,18 

4,i38 

34 

4,172 

32 

4,204 

33 

4,237 

32 

4,269 

33 

4,3o2 

3i 

4,333 

32 

4,365 

32 

4,3g7 

3i 

4,428 

3i 

o,o324 

0,19 

4,367 

35 

4,402 

34 

4,436 

35 

4,471 

34 

4,5o5 

34 

4,539 

34 

4,573 

33 

4,606 

33 

4,639 

33 

4,672 

33 

o,o36i 

0,20 

4,594 

37 

4,63 1 

3? 

4,668 

36 

4,704 

36 

4,74o 

36 

4,776 

36 

4,812 

35 

4,847 

35 

4,882 

35 

4,917 

34 

c3,o4oo 

0,2 1 

4,822 

39 

4,861 

38 

4,899 

39 

4,938 

37 

4,975 

38 

5,oi3 

37 

5,o5c 

37 

5,087 

37 

5,124 

37 

5,161 

36 

0,044 1 

0,22 

5,049 

4i 

5,ogo 

40 

5,i3i 

40 

5,170 

40 

5,210 

40 

5,25c. 

39 

5,28g 

39 

5,328 

38 

5,366 

38 

5,4o4 

38 

0,0484 

0,23 

5,276 

43 

5,319 

42 

5,36 1 

42 

5,4o3 

42 

5,445 

4i 

5,486 

41 

5,527 

4i 

5,568 

40 

5,608 

4o 

5,648 

40 

0,0529 

0,24 

5,5o2 

45 

5,547 

44 

5,591 

44 

5,635 

AA 

5,679 

43 

5,722 

43 

5,765 

42 

5,807 

42 

5,849 

42 

5,891 

42 

0,0576 

0,25 

5,729 

46 

5,775 

/fi 

5,821 

46 

5,867 

45 

5,912 

45 

5.957 

45 

6,002 

45 

6,047 

43 

6,090 

A4 

6,1 34 

i 

0,0625 

0,26 

5,954 

49 

6,00  3 

48 

6,o5i 

48 

6,099 

47 

6,i46 

47 

6,193 

46 

6,239 

46 

6,285 

46 

6,33i 

46 

6,377 

45 

0,0676 

0,27 

6,180 

5o 

6,23o 

5o 

6,280 

5o 

6,33o 

49 

6,379 

49 

6,428 

48 

6,476 

48 

6,524 

48 

6,572 

47 

6,6 1  g 

47 

0,0729 

0,28 

6,4o4 

53 

6,457 

52 

6,509 

5i 

6,56o 

5i 

6,611 

5i 

6.662 

5o 

6,712 

5o 

6,762 

5o 

6,812 

49 

6,861 

49 

0,0784 

0,29 

6,629 

54 

6,683 

54 

6,737 

54 

6,791 

53 

6,844 

52 

6,896 

52 

6,948 

52 

7,000 

52 

7>o52 

5o 

7,102 

5i 

0,084 1 

o,3o 

6,853 

56 

6,909 

56 

6.965 

55 

7,o2r 

55 

7,075 

55 

7,1 3o 

54 

7,184 

54 

7,238 

53 

7,291 

53 

7,344 

52 

0,0900 

0,3 1 

7,076 

59 

7,i35 

57 

7,19= 

58 

7,25o 

j7 

7,307 

56 

7,363 

56 

7,419 

56 

7,475 

55 

7,53o 

54 

7,584 

55 

o,og6i 

0,32 

7,299 

60 

7,359 

60 

7,4 1 9 

60 

7,479 

59 

7,538 

58 

7,596 

58 

7,654 

57 

7,711 

57 

7,768 

57 

7,825 

56 

0,1024 

0,33 

7,521 

63 

7,584 

62 

7,64(> 

61 

7,707 

61 

7,768 

60 

7,828 

60 

7,888 

59 

7,947 

59 

8,006 

59 

8,o65 

58 

0,1  o8g 

0,34 

7,743 

64 

7,807 

64 

7,871 

64 

7,935 

63 

7,998 

62 

8,060 

62 

8,122 

61 

8,i83 

61 

8,244 

60 

8,3o4 

60 

0, 1 1 56 

0,35 

7.964 

67 

8,o3i 

66 

8,097 

65 

8,162 

65 

8,227 

64 

8,291 

64 

8,355 

63 

8,4i8 

63 

8,48i 

62 

8,543 

62 

0,1225 

o,36 

8,184 

69 

8,253 

68 

8,321 

68 

8,389 

67 

8,456 

66 

8,522 

66 

8,588 

65 

8,653 

64 

8,717 

65 

8,782 

63 

0,1296 

0,37 

8,4o4 

71 

8,475 

70 

8,545 

70 

8,6i5 

G9 

8,684 

68 

8,752 

68 

8,820 

67 

8,887 

67 

8,954 

66 

g,020 

65 

0,1 36g 

o,38 

8,623 

73 

8,6g6 

73 

8,769 

71 

8,84o 

71 

8,911 

71 

8,982 

69 

9,o5 1 

G9 

9,120 

69 

9,-89 

68 

9,257 

67 

0,1 444 

0,39 

8,842 

75 

8,917 

74 

8,991 

74 

9,o65 

73 

9,1 36 

73 

9,211 

71 

9,282 

71 

9,353 

71 

9,424 

70 

9,494 

69 

0,l52I 

o,4o 

9>o59 

78 

9,i37 

76 

9,2i3 

76 

9,289 

75 

9,364 

75 

9 -430 

74 

9,5i3 

73 

9,586 

72 

9,658 

72 

9,73o 

71 

0,1600 

0,4 1 

9,276 

80 

9,356 

79 

9,435 

78 

9,5i3 

77 

9,590 

■76 

9,666 

76 

9,742 

75 

9,817 

75 

9,892 

74 

9,966 

73 

0,1681 

0,42 

9'492 

82 

9,574 

81 

9.655 

8u 

9,735 

80 

9,8 1 5 

78 

9,893 

78 

9.971 

78 

10,049 

76 

10,125 

76 

10,201 

75 

0,1764 

0,43 

9,101 

84 

9,791 

84 

9,875 

82 

9,957 

82 

10,039 

80 

10,1 19 

81 

I0,20' 

79 

10,27g 

78 

10,357 

78 

10,435 

78 

0,1849 

0,44 

9«2i 

87 

10,008 

85 

10,093 

85 

10,178 

84 

10,262 

83 

10,345 

82 

10,427 

82 

io,5og 

80 

io,58g 

80 

10,669 

79 

0,1936 

0,45 

1 0,1 34 

S9 

10,223 

88 

io,3ii 

87 

10,398 

86 

10,484 

85 

10,569 

85 

10,654 

83 

10,737 

83 

10,820 

82 

10,902 

83 

0,2025 

o,5o 

II, 184 

lOI 

11,985 

101 

11,386 

99 

11,485 

97 

1 1 ,582 

97 

11,679 

9O 

11,775 

95 

1 1 ,870 

93 

1 1  ,g63 

^l 

i2,o56 

92 

o,25oo 

0,55 

12,200 

116 

I2,3i6 

ii4 

i2,43o 

112 

12,542 

II I 

12,653 

no 

12,763 

108 

12,871 

107 

I2,g78 

io5 

i3,o83 

io5 

i3,i88 

io3 

o,3o25 

0,60 

1 3, 166 

1 35 

i3,3oi 

i3i 

1 3,432 

129 

i3,56i 

126 

13,687 

125 

i3,8i2 

122 

13,934 

121 

i4,o55 

118 

14,173 

118 

14,291 

116 

o,36oo 

0,65 

1 4,36 1 

i56 

i4,5i7 

i4g 

i4,666 

i45 

14,811 

i4o 

i4,95i 

i38 

15,089 

i35 

l5,224 

1 33 

1 5,357 

i3o 

0,4225 

0,70 

16,049 

1 63 

16,212 

i55 

16,367 

i5i 

0,4900 

,1985 

,2048 

,2113 

,2178 

,2245    1 

,2312   1 

.2381 

,2450 

,2521 

.2592 

c"- 

Ji   .    (r  +  r")»    or    r=  -)-  r"=  nearly.                                                                                                       | 

2l3 

2l5 

217 

2ig 

221 

21 

22 

22 

22 

22 

43 

43 

43 

AA 

AA 

64 

65 

65 

66 

66 

85 

86 

87 

88 

88 

107 

108 

loq 

no 

111 

12,8 

129 

i3o 

i3i 

1 33 

1 49 

i5i 

l52 

i53 

i55 

170 

172 

174 

175 

177 

192 

194 

193 

197 

199 

45 
67 
89 

112 
1 34 

1 56 
178 
201 


225 

227 

229 

23 

23 

23 

45 

45 

46 

68 

68 

69 

90 

91 

92 

ii3 

114 

ii5 

i35 

1 36 

1 37 

1 58 

i5q 

160 

180 

182 

1 83 

2o3 

2o4 

206 

23l 

2  32 

233 

2  34 

235 

236 

237 

238 

239 





— 













23 

23 

23 

23 

=4 

24 

24 

24 

24 

46 

46 

47 

47 

47 

47 

47 

48 

48 

6q 

70 

70 

70 

71 

71 

71 

71 

72 

92 

93 

93 

94 

94 

94 

95 

95 

96 

iih 

n6 

117 

117 

118 

lib 

119 

iiq 

120 

i3q 

i3q 

1 40 

i4o 

i4i 

142 

142 

i43 

143 

162 

162 

i63 

1(34 

i65 

i65 

166 

167 

167 

i85 

186 

186 

187 

188 

189 

190 

190 

19; 

208 

209 

210 

211 

212 

212 

2l3 

214 

2l5 

240 

24 1 

2.13 

243 

24 

24 

24 

24 

48 

48 

48 

4q 

72 

72 

73 

73 

96 

9b 

97 

97 

120 

121 

131 

122 

1 44 

i45 

145 

i46 

16b 

i6g 

169 

170 

192 

193 

i(j4 

iq4 

216 

217 

318 

219 

TABLE  II.  —  To  find  the  lime  T\  tlie  sum  of  the  radii  r-\-r",  and  the  chord  c  being  given. 


of  Ihe   Radii    r -j- '' 


Chor.l 

c. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

0,0  5 
o,<'(> 
o,(i^ 
o,oti 

0,10 
0,1 1 
0,1  :' 
o.ij 
0,14 

0,1 5 
0,16 
0,17 
0,18 

O..If) 
0,3(i 

0,2 1 

0,32 
0,23 
0,34 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 


0,73 


l>ay5  |ilil'. 


0,35  8 
0,36  8: 
0,37 


o,38 


0,000 
0,248 
0,497 
.0,745 
0,993 

1,241 

1  ,.f()0 

1,738 
I  ,l|S(i 
2,234 

3.4S1 
2,729 
2,9 
3.224 

3,4 

3,719 
3,965 

4,213 

4.459 

4,7o5 

4,951 
5,197 
5,442 
5,688 
5,933   A'l 


0,74 


Days  liiif. 


6,178 
6,423 

6,666 
6.gio 
7, 1 53 

7,639 
7,881 
8,123 
8,364 


,6o5 
,845 
l,o85 


0,39    9,563 


o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
0,65 
0,70 

0,75 


9,324 


9,801 
10,009 
10,276 
io,5i3 
10,748 

10,984 
I2,i48 
13,391 
14,407 
15,487 
i6,5i8 


0,000 
o,25o 
o,5oo 
o,75o 
1,000 

I,25o 

i,5oo 
i,75o 

1. 999 
2,349 

2,498 

2,748 

■■'■99' 
3,246 
3,495 

3,-44 
3,993 
4,241 
4,489 
4,-37 

4,985 
5,233 
5,480 

5,727 
5,974 

6,221 
6,467 
6,71 3 
6,958 
7,2o3 

7.448 
7,692 
7,936 
8,180 
8,423 

8,666 
8,908 
9,i5o 
9,3iii 
9,603 

9.S72 
10,112 
io,35i 
10,589 
10,827 

1 1 ,064 
12,239 
13,393 
14,521 
5,616 
1 6,66  5 


18 


0,75 


Days  |iiif. 


80 

90 
101 
ii3 

127 
144 


0,000 
0,252 

O,5o3 
0,-55 
1 ,007 

1,2  58 
i,5jo 
1,-61 

2,Ol3 

2,264 
2 

2 .7(>6 

3,0 

3,268 

3,519 

3,769 
4,020 
4,370 
4,520 
4,770 

5,019 
5,269 
5,5i8 
5,766 
6,01 5   4i 


0,76 


D.iys  |iliC. 


6,263 

6,5 11 
6.759 
7,006 
7,253 

7,5oo 
7,746 
7.995 
8,237 
8,482 

8,727 
8,971 
9,214 
9.458 
9,700 

9.942 
10,184 
10,425 
io,665 
10,905 

ii,i44 
12,329 
1 3,49 
i4,634 
1 5,743 
16,809 

17.799 


43 
M 
46 
48 
5o 

5i 
53 
55 
57 
59 

60 
62 
64 
65 
68 

70 
71 
73 
76 

77 

79 
90 
101 
112 

125 

i4i 
169 


0.000 
0,253 
o,5o' 
0,760 
1, 01 3 

1 ,367 
1,5 

1,7-3 
2,026 

3,2-9 

2,53 

2,785 

3,o38 

3,390 

3,542 

3,795 
4,047 

4.399 
4.55o 
4,802 

5,o53 
5,3o4 
5,555 
5,8o5 
6,o56 

6.3o6 

6,5 

6,8o5 

7,o54 

7,3o3 

7,55i 
7,799 
8,047 
8,394 
8,54i 


8,787   60 
9,o33    62 


0,77 


Diiy.i  |dif. 


0,000 
0,255 
0,5 10 
0,765 
1,020 

1,375 
i,53u 
1,785 
2,o4o 
2,294 


2,549 

2,8o3 
3,o58 
3,3 12 
3,566 

3,820 
4,073 
4,327 
4,58o 
4.834 

5,087 
5,339 
5,592 
5,844 
6,096 

6,348 
6,599 
6,85o 
7,101 
7,352 

7,602 
7,852 
8,101 
8,35o 
8,599 


9,278 
9,52" 
9.768 

10,012 
10,255 
1 0,498 
10,741 
10,982 

[1,223 

12,419 

[3,595 
■746 

1 5,868 
i6,g5o 

i-,968 


64 
66 
67 

69 

71 

73 
74 

77 

79 
88 

99 
[1 1 
124 
139 

161 


9.095 
9,342 
9,589 
9,835 

10,081 
10,326 
[0,57[ 
[o,Si5 
11,059 

[l,3o2 
I2,507 

13,694 

14,857 
15,992 
17,089 

[8,139 


i3 
i5 

16 
18 

19 
21 

23 

25 

27 
28 

3o 
3i 

33 
35 

37 
38 
4o 

42 
AÂ 
46 

47 
48 

5o 

52 

54 
56 

57 

59 
61 
63 
65 
67 

69 

71 
72 
75 
76 

78 
88 

98 
110 
122 
i36 

1 57 


0,78 


Duys  |dir. 


,2665   I  ,2738       ,2813   |   ,2888       ,2965       ,3042        (? 


0,000 
0,357 

0,5 1 3 

0,770 
1,027 

1,383 
1 ,54f 
1,796 
2,o53 
2,309 

2,565 

2,831 

3,077 

3,333 
3,589 

3,845 
4,100 
4,355 
4,610 
4,865 

5,130 

5,374 

5,629 

5,88: 

6, 1 36 

6,390 
6,643 
6,896 
7.148 
7,4oo 

7,652 
7.904 

8,i55 
8,406 
8,656 

8,906 
9,1 56 
9,4o5 
9,654 
9,902 

io,i5o 
10,397 
10,643 
10,890 
ii,i35 


ii,38o 
12,595 
13,792 
14.967 
i6,ii4 
17,225 

18,286 


12 
i3 
i5 

17 

'9 
20 
22 

33 

26' 
28 
3o 

33 

33 
35 
36 

39 

40 

4i 
43 
45 

47 
49 

5o 

52 

54 
55 

57 

59 
61 
63 
64 
66 

68 

70 
72 
73 
76 


0,0000 
0,0001 
0,00114 
0,0009 

O.fKl!  fi 
0,0025 

o,oo36 
0,0049 
o,oo()4 
0,0081 

0,0100 
0,01  2  I 
o,oi44 
0,0169 
0,0196 

0,0225 
o,o256 
0,0289 
o,o324 
o,o36i 

o,o4oo 
0,044 1 
0,0484 
0,0539 
0,0576 

0,0635 
0,0676 
0,0729 
0,0784 
o,oS4i 

0,0900 
0,09(11 
0,1024 
0,1089 
0,1 1 56 

0,I235 

0,1396 
0,1369 
0,1444 

0,l531 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,2025 

O,35oo 

o,3o35 
o,36oo 
0,4225 

lO 

0,5625 


(r  -\-  r'"^)  or  r-  -f-  r"^   nearly. 


244  245  246  247  248  249  25o  25i   252  253  254  2551  256|  257 


24 
49 

-3 

98 

122 

i46 
171 
195 

220 


25 

49 

74 

98 

123 

i47 
172 
196 

221 


25 
49 

74 
98 

123 

1 48 
172 
197 

231 


25 

49 

74 
99 

134 

1 48 
173 


25 

5o 

74 

99 

124 

i4q 

174 

198 
333 


25 

5o 

75 
100 

125 

i49 

174 

199 
224 


25 

5o 

75 

too 

125 

i5o 
175 
200 

225 


25 

5o 
75 
100 
126 
i5i 
176 
2or 
236 


25 

5o 

76 

lOI 

[26 

i5i 
176 
202 

227 


25 

5i 

76 
10 
127 

l53 

177 

202 
228 


25 

5i 

76 

102 

127 

l53 

178 

2o3 
229 


26 

5i 

77 

ro2 

128 

i53 

179 
2o4 
23o 


26 

5 

77 
102 
128 
i54 

179 

2o5 

2  3o 


26 

5i 
77 
io3 
129 
1 54 
180 
206 

23l 


Prop,  imrts  tor  Uio  simi  ul'  tliu  Radii, 

■  I  2  I  3  I  4  I  5  I  6  I  7  I  8  I  9 


35 
36 

37 
38 
39 

4o 
4i 
42 
43 
44 

45 
46 

47 

48 
49 

5o 
5i 

52 

53 
54 

55 
56 

57 

58 
59 

60 
61 
62 
63 
64 

65 
66 

67 
68 

69 

70 
80 

90 

[OO 


0 

0 

0 
1 
1 
1 

0 
1 
1 
2 

3 

2 

2 

2 

3 

3 

2 

2 

3 

2 

3 

4 

2 

3 

4 

2 

3 

4 

2 

4 

5 

3 

4 

5 

3 

4 

6 

3 

5 

6 

3 

5 

6 

3 

5 

7 

4 

5 

7 

4 

6 

8 

4 

6 

8 

4 

6 

8 

4 

7 

9 

5 

7 

9 

5 

7 

10 

5 

8 

10 

5 

8 

10 

5 

8 

I  I 

6 

8 

1  1 

9   12 


10 


14 

11  i4 
i5 


[I 
8  12 


12 
i3 
i3 

i3 
i3 
i3 
i4 
i4 

i4 

16 

18 

1  o  I  30 


i3 
3 

14 
i4 
i5  17 


18 
18 
19 
19 

30 

20  24 
25 
25 
26 
26 


21  38  35 


3o  36 

3i 

3i 

33 


33 


3 
4 

5 
5 
6 

7 
8 

9 
10 

13 

i3 

i4 
i4 
i5 
16 


24 
35 
26 
26 
27  3i 

32 
32 

33 
34 
35 


37 
37 
38 
38  45 


59 
59 
60 
61 
55  63 


49  56 
56  64 
63  72 
60 1  70 1 80 


a5 


TABLE  H.  —  To  find  the  time  T;  the  sum  of  the  radii  r-\-r".,  and  the  chord  c  being  given. 


Sum  of  the  radii  r- 


Chord 
C. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,1 1 
0,1 3 
0,1 3 
o,i4 

o,i5 
,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
o,32 
0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
0,39 


0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
o,85 


0,79 


Day3   jdif. 


0,000 
0,258 
o,5i7 
0,775 
i,o33 

1,292 
i,55o 
1,808 
2,066 
2,324 

2,582 

2,84o 
3,097 

3.355 
3,612 

3,869 
4,126 
4,383 
4.640 
4,897 

5,i53 

5,409 

5,665 

5,92 

6,176 

6,43] 
6,686 
6,941 
7,195 
7.449 

7.702 
7,956 
8,209 
8,461 
8,7i3 

8,965 

9'2i7 
9,468 
9,718 
9,968 

10,218 
10,467 
1 0,7 1 5 
10,963 
11,211 

11,457 

12,682 

1 3,1  _ 

15,075 

16,235 

17,360 

18,439 


0,80 


Days  \  dif. 


0,000 
0,260 
0,520 
0,780 
I,o4o 

i,3oo 
1,559 
1,819 
2,079 
2,339 

2,857 
3,1 17 
3,376 
3,635 

3,6 

4,i53 

4,4ii 

4.670 

4,928 

5,186 
5,444 
5,701 
5,959 
6,216 

6,4 

6,729 

6,985 

7.241 

7.497 

7,752 
8,007 
8,262 
8,5i6 
8,77< 

9,024 

9.277 
9,53o 
9,782 
io,o34 

10,28 

io,536 

10,786 

ii,o36 

11,285 

11,53 

12,769 

13,986 

i5,i83 

16,354 

17.493 

i8,588 
19,609 


0,81 


Days  Idir. 


,3121 


174 


,3-200 


0,000 
0,262 
0,523 
0,785 
1,046 

i,3o8 
1 ,569 
i,83'i 
2,092 
2,353 

2,61 

2,875 
3,i36 
3,397 
3,658 

3,918 

4,179 
4,439 
4,699 
4,9^9 

5,218 
5,478 
5,737 
5,996 
6,255 

6,5 1 3 
6,772 
7,o3o 
7,287 
7,545 

7,802 
8,059 
8,3i5 
8,571 
8.827 

9,082 
9,337 

9.591 
9.845 
10,099 

10,352 
10, 60  5 
10,857 
11,109 
1 1 ,36o 

11.610 
12,855 
14,082 
15,289 
16,472 
17,624 

18,736 
9,783 


0,82 


Days  |dir. 


0,000 
0,263 
0,526 

0,790 
I  ,o53 

i,3i6 
1.579 
1,842 
2,io5 
2,368 

2,63o 
2,893 
3,i56 
3,4:8 
3,680 

3,943 
4,2o5 
4.466 
4,728 
4,990 

5,25i 
5,5i2 
5,773 
6,o34 
6.294 

6,554 
6,814 

7.074 
7,333 
7.592 

7,85i 
8,109 
8,368 
8,625 
8,883 

9,i4o 
9,396 
9,653 
9.908 
10,164 

10,419 
10,673 
10,927 
11,181 
11,434 

11,686 
12,940 

14,177 
15,395 
16,589 
17.754 

18,880 
19,960 


0,83 


Days  |(lif". 


,3281 


25 

28 
29 

3o 

32 

34 
35 
37 
39 

4i 
42 
M 
46 
47 

49 
5i 

52 

54 
55 

57 

59 
60 
63 
64 

66 
68 

70 
71 
73 

75 
84 
94 
io4 
116 
128 

143 
162 


0,000 
0,265 
o,53o 

0,794 
1,059 

1,324 
1,588 
1,853 
2,118 

2,382 

2,646 

2,91 

3,175 

3,439 

3,7o3 

3,967 
4,23o 
4.494 

4.757 
5,020 

5,283 
5,546 
5,808 
6,071 
6,333 

6,595 
6,856 
7." 

7.379 
7,639 

7,900 
8,160 
8,420 
8,679 
8,938 

9.197 
9.455 
9.7 1 3 

9.971 
10,228 

io,485 
10,741 
10,997 
11,252 

1 1 ,507 

1 1 ,761 
i3,024 
14,271 

1 5,499 
i6,7o5 
17,882 

19,023 
20,112 


0,84 


Days  |dir. 


5o 
52 
54 

56 

57 

59 
6i 
62 
64 

65 

67 
69 

71 
73 

75 
84 
94 
104 

114 
126 

i4o 
159 


0,000 
0,266 
0,533 

0,799 
i,o65 

1,332 
1,598 
1,864 
2,i3o 

2,396 

2,662 
2.928 

3,194 
3,460 
3,725 

3,991 

4,256 
4,52 
4.786 
5,o5i 

5,3 1 5 
5,58o 
5,844 
6,108 
6,3 

6,635 
6,898 
7,161 
7,424 
7,686 

7.948 
8,210 
8,472 
8,733 
8,994 

9,254 
9,5i 

9.77 
io,o33 
10,292 

io,55o 
0,808 
1 1 ,066 
11,32 
1 1 ,58o 

11,836 

i3,io8 

i4,36 

i5,6o3 

16,819 

1 8,008 

19,163 
20,271 


0,85 


Days  |dir. 


23 


o,ooc> 

0,268 

0,536 
0,804 
1,072 

1 ,340 
1 ,608 
1,875 
2,143 

2,4  II 

2,678 
2,946 
3,2i3 
3,480 
3,747 

4,014 
4,281 
4.548 
4,814 
5,081 

5.347 
5,6i3 
5,879 
6,144 
6,4 10 

6,675 
6,940 

7,204 

7.469 
7,733 

7,997 
8,260 
8,523 
8,786 
9,049 

9,3ii 
9,572 
9,834 
10,095 
10,355 


0,86 


Da 


I  |dif. 


10,616 

10,875 

ii,i35 

71  11 ,394 

72  11,652 


3362       ,3445       ,3528 


11,910 
13,191 

14,457 
1 5,706 

i6.q33 
18,1 34 

19,302 

20,427 
21,475 


0,000 
0,270 
0,539 
0,809 
1,078 

1,348 
1,617 
if^^ 
2,i56 
2,425 

2,694 
2,963 

3,232 

3,5oi 
3,77c 

4,o38 
4,307 
4,575 
4,843 
5,111 

5,379 
5,646 
5,914 
6,181 
6,448 

6,715 
6,98 

7.247 
7,5i3 

7.779 

8,044 
8,3io 
8,574 
8,839 
g,io3 

9,367 
9,63o 
9,894 
io,i56 
10,419 

10,680 
10,942 
i,2o3 
11,464 
11,724 

11,983 
13,274 
14,549 
1 5,808 
17,045 
i8,258 

19,439 
20,579 
21,655 


0,87 


Days  I  dif. 


,3613 


49 

5i 
53 
54 

56 
58 

59 

6 

62 

65 
66 
68 
69 

71 

73 
82 

92 
101 
112 
123 

i36 
i5i 
173 


0,000 
0,271 
0,542 
0,81 3 
1,084 

1,355 
1,626 
1,897 
2,168 
2,439 

2,710 
2,980 
3,25i 
3,521 
3,791 

4,062 
4,332 
4,602 
4.871 
5,i4i 

5,4 1 

5,679 

5,948 

6,21 

6,486 

6,754 
7,022 
7.290 
7,558 
7,825 

8,092 
8,359 
8,625 
8,892 
9,i57 

9,423 
9,688 
9,953 
10,21 
10,48 

10,745 
1 1 ,008 
11,371 
11,533 
11,795 

i2,o56 
i3,356 
i4,64i 
15,909 
17,157 
i8,38i 

19,575 
2o,73o 
21,828 


0,88 


Day 9  [dif. 


,3698 


0,000 
0,273 
0,545 
0,818 
1,091 

1 .363 
1,636 
1,908 
2,181 
2,453 

2,725 

2.997 
3,269 

3,541 
3,8 1 3 

4,o85 
4,357 
4,638 

4,899 
5,170 

5,44 1 
5,712 
5.983 
6,253 
6,523 

6,793 
7.o63 
7,333 
7,602 
7,871 

8,i39 
8,408 
8,676 
8,944 
9,211 

9,478 
9.745 
10,012 
10,278 
10,543 

10,809 
1 1 ,0-4 
11,338 
1 1 .602 
11,866 

12,120 
i3,437 
i4,73i 
16,009 
17,267 
i8,5o2 

19,709 
20,878 
21,996 


9 
II 
12 

i4 

16 

17 
19 
21 
22 

23 

24 

26 
28 

3o 

32 

33 
34 
36 
38 

39 
41 

42 

45 

47 

49 
5o 

53 

54 

56 

57 
58 
60 
62 

63 
65 
67 

69 

70 

72 
81 

90 
100 
no 
121 

l32 

1 47 
164 


0,0000 
0,0001 
o,ooo4 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
o,<.>o8i 

0,0100 
0,01  2 1 
0,01 44 
0,0169 
0,0196 

0,0225 
o,o356 
0,0289 
o,o324 
o,o36i 

o,o4oo 
0,044 1 
0,0484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

0,0900 
0,0961 
0,1024 
0,1089 
0,1 1 56 

0,1225 
0,1 296 
0,1 36g 
0,1 444 
0,1 52  I 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,2025 
0,2600 
o,3o25 
0,3600 
0,4225 
0,4900 

0,5635 
0,6400 

0,7235 


,3785       ,3872 


.  (r  -|-  ^")"  or   r^  -J-  r"^    nearly. 


246 

247 

248 

249 

25o 

25l 

262 

253 

254 

255 

256 

257 

258 

359 

260 

261 

262 

263 

264 

265 

366 

267 

268 

25 

25 

25 

25 

25 

25 

25 

25 

25 

26 

26 

26 

26 

26 

26 

26 

26 

26 

26 

27 

27 

27 

27 

49 

74 

4n 

5o 

5o 

5o 

5o 

5o 

5i 

5i 

5i 

5i 

5i 

52 

52 

52 

52 

52 

53 

53 

53 

53 

53 

64 

74 

74 

75 

75 

75 

76 

76 

76 

77 

77 

77 

77 

78 

78 

78 

79 

79 

79 

80 

80 

80 

80 

9« 

123 

99 

99 

100 

100 

TOO 

lOI 

lOI 

102 

102 

102 

io3 

io3 

io4 

104 

io4 

io5 

io5 

106 

106 

106 

107 

107 

124 

T24 

125 

125 

126 

126 

137 

127 

128 

128 

I2q 

1 20 

i3o 

i3o 

i3i 

i3i 

l32 

l32 

i33 

i33 

1 34 

134 

T-18 

r48 

t4o 

i4q 

i5o 

i5i 

i5i 

l52 

l52 

i53 

i54 

1 54 

i55 

i55 

1 56 

l57 

1 57 

i58 

1 58 

i5q 

160 

160 

161 

172 

173 

174 

174 

175 

176 

176 

177 

178 

179 

179 

180 

181 

181 

182 

i83 

i83 

184 

i85 

186 

186 

187 

188 

197 
321 

198 
222 

108 

199 

200 

201 

202 

202 

203 

204 

2o5 

206 

206 

207 

208 

209 

310 

210 

211 

212 

3l3 

214 

2l4 

2i3 

224 

125 

226 

327 

228 

229 

23o 

23o 

23 1 

232 

233 

234 

235 

236 

237 

238 

239 

239 

240 

241 

TABLE  II 

•  — 

fo  find  the  time  T\ 

the  sum 

oft 

\e  radii  r-f-  r". 

ind  tlic 

chord 

c  be 

ng  given 

Sum  ol  tbe  Radii  r  -f-  r".                                                                  j 

I'rop.  parts  for  the  sum  of  the  Radii.    1 
1  |2|3|4|5|6|7|8|9  1 

Chord 

c. 

0,89 

0,90 

0,91 

0,92 

0,93 

0,94 

1  c 

2  c 

3  < 

0 
0 

I 

0 

I 
1 

0  I       I 

1  I      I 
12       2 

I 
I 
2 

I 

2 
2 

I 
2 
3 

Days  |dif. 

Da)  s  \M\ 

Uays  ]dil'. 

Ua>s  Idil 

Uays  Idif. 

Days  |dir. 

0,00 

o,oou 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,2-4 

2 

0,276 

I 

0,277 

2 

0,279 

I      0,280 

2 

0,282 

1 

0,0001 

4    ( 

,     I 

I 

2      : 

2 

3 

3 

4 

0,0-2 

0,548 

3 

0,55l 

4 

0,555 

3 

o,558 

3     0,56 1 

3 

o,564 

3 

0,0004 

o,o3 

0,823 

4 

0,827 

5 

o,832 

4 

o,836 

5    0,84 1 

4 

0,845 

5 

o,ooog 

5 

1 

2 

2     3|   3| 

4 

4 

5 

0,04 

i><i9" 

6 

i,io3 

6 

1,109 

6 

i,ii5 

6     1,121 

6 

1,127 

6 

0,0016 

6 

1 

2 

2 

i    4 

4 

5 

5 

7 

I 

2 

3     4    4 

5 

6 

6 

o,o5 

1,371 

8 

1 ,379 

7 

1 ,386 

8 

1,394 

7     i,4oi 

8 

1 ,409 

7 

0,0025 

8 

2 

2 

3     4    5 

6 

6 

7 

0,06 

1,645 

9 

1 ,654 

9 

1 ,6(i3 

9 

1,6-2    I 

0     1 ,682 

9 

1,691 

9 

o,oo36 

9 

2 

3 

4 

3    5 

6 

7 

8 

0,0- 

i>9'9 

II 

r,93o 

10 

1,940 

1 1 

1 ,95 1     1 

I     1 ,9(12 

10 

1 ,972 

11 

0,0049 

3 

3    6 

0,08 

2,193 

12 

2,205 

12 

2,217 

i3 

2,23o     I 

2     2,242 

12 

2,254 

12 

0,0064 

10 

2 

4 

7 

8 

9 

0,09 

2,46-: 

i4 

2,481 

i3 

2,494 

14 

2,5o8    I 

4       2,522 

i3 

2,535 

i4 

0,008 1 

1 1 
1  2 

2 
2 

3 
4 

4 
5 

'■>     7 
J     7 

8 
8 

9 
10 

10 
1 1 

0,10 

2,74 1 

i5 

2,756 

i5 

2,771 

16 

2,787  I 

5    2,802 

i5 

2,817 

i5 

0,01 00 

1 3 

3 

4 

5 

7     8 

9 

10 

1 2 

0,1 1 

3,014 

17 

3,o3i 

17 

3,o48 

17 

3,o65    I 

7     3,082 

16 

3,098 

17 

0,01  2 1 

i4 

3 

4 

6 

7     8 

10 

1 1 

i3 

0,12 

3,288 

'9 

3,3o7 

18 

3,325 

18 

3,343    I 

8    3.36i 

18 

3,379 

18 

0,01 44 

i5 
16 

17 

I     3 
1     3 
I     3 

5 
5 
5 

6 
6 

7 

3    9 
B  10 
d  10 

i4 

0,1 3 

3,562 

20 

3,582 

'9 

3,601 

20 

3,621    2 

0    3,64 1 

20 

3,661 

jg 

0,0169 

1 1 

1 2 
i3 
14 

0,1 4 

3,835 

22 

3,857 

21 

3,878 

21 

3,899   2 

2    3,921 

21 

3,942 

21 

0,0196 

I  1 
12 

i5 

0,1 5 

4,108 

23 

4,i3i 

23 

4,1 54 

23 

4,177   2 

3    4,200 

23 

4,223 

22 

0,0225 

18 

i    4 
2    4 

5 
6 

7 

^  " 

i3 
i3 

14 
i5 

16 

0,16 

4,38i 

25 

4,406 

25 

4,43 1 

24 

4,455   2 

4    4,479 

24 

4,5o3 

24 

0,0256 

19 

8    io|ii 

17 

0,17 

4,654 

27 

4,681 

26 

4,707 

26 

4,733    2 

5    4,758 

26 

4,784 

26 

0,0289 

20 

1  4 

2  4 
2    4 

6 

8    I 

012 

i4 
i5 

16 

18 

0,18 

4,927 

28 

4,955 

28 

4,983 

37 

5,010   2 

8    5,o38 

27 

5,o65 

27 

o,o324 

21 

6 

8    1 

T      ,^ 

17 
18 

19 
20 

0,19 

5,200 

29 

5,229 

3o 

5,259 

29 

5,288   2 

8    5,3 16 

29 

5,345 

29 

o,o36i 

22 

7 

9    1 1|  i3 

i5 

o,ao 

5,473 

3o 

5,5o3 

3i 

5,534 

3i 

5,565   3 

0    5,595 

3o 

5,625 

3o 

o,o4oo 

23 

24 

2    5 
2     5 

7 
7 

9    ' 
10    I 

2    l4 

2  14 

16 

I  7 

18 
'9 

21 

22 

0,21 

5,745 

32 

5,777 

33 

5,810 

32 

5,842    3 

2    5,874 

32 

5,906 

3i 

o,o44i 

0,32 

6,01- 

34 

6,o5i 

34 

6,o85 

34 

6,119   3 

3    6,i52 

33 

6, 1 85 

34 

o,o484 

25 

3     5 

8 

10    1 

3  i5 

18 

20 

23 

0,23 

6,289 

36 

6,325 

35 

6,36o 

35 

6,395   3 

5    6,43o 

35 

6,465 

35 

o,o52g 

26 

3     5 

8 

lo    1 

3  16 

18 

21 

23 

0,24 

6,56i 

37 

6,598 

37 

6,635 

37 

6,672   i 

6    6,708 

37 

6,745 

36 

0,0576 

27 

28 

3     5 
3    6 

8 
8 

1 1    I 
1 1    I 

4  16 

4  17 

19 
20 

22 
22 

24 

25 

0,25 

6,832 

39 

6,871 

39 

6,gio 

38 

6,948    I 

8    6,986 

38 

7,024 

38 

0,0625 

29 

3    6 

9 

12    I 

5  17 

20 

23 

26 

0,26 

-,io4 

40 

7,i44 

40 

7,lS4 

4o 

7,224   i 

0    7,264 

39 

7,3o3 

40 

0,0676 

0,27 

7-3-5 

42 

7,417 

4i 

7,458 

42 

7,5oo    I 

I     7,541 

4i 

7,582 

4i 

0,0729 

3o 

3    6 

9 

9 

10 

12    I 

5  18 

21 

24 

27 

0,28 

7,646 

43 

7,689 

^^ 

7,732 

M 

7,776   ^ 

2    7,818 

43 

7,861 

42 

0,0784 

3i 

3    6 

12    1 

6  19 

22 

25 

28 

0,29 

7>9i6 

45 

7,961 

45 

8,006 

45 

8,o5i    I 

4    8,095 

^A 

8,139 

A4 

0,084 1 

32 

3    6 

i3    1 

6  19 

22 

26 

29 

33 

3     7 

10 

i3    I 

7  20 

23 

26 

3o 

o.3o 

8,r86 

47 

8,233 

47 

8,280 

46 

8,326   i 

'6    8,372 

46 

8,4i8 

45 

o,ogoo 

34 

3     7 

10 

14    I 

7  20 

24 

27 

3i 

0,3 1 

8,457 

48 

8,5o5 

48 

8,553 

48 

8,601    i 

i7    8,648 

48 

8,696 

47 

0,0961 

0,32 

8,726 

5o 

8,776 

5o 

8,826 

49 

8,875    . 

i9    8,924 

49 

8,973 

49 

0,1024 

35 

4     7 

11 

14    I 

8  21 

25 

28 

32 

0.33 

8,996 

5i 

9,047 

52 

9,099 

5i 

9,1 5o  ; 

)0    9,200 

5i 

9,25i 

5o 

0,1089 

36 

4    7 

II 

14    I 

8  22 

25 

o9 

32 

0,34 

9,265 

53 

9,3 1 8 

53 

9^371 

53 

9,424 

)2       9,476 

52 

9,528 

52 

0,1 156 

37 
38 

4    7 
4    8 

1 1 
1 1 

i5    I 
i5    I 

922 
9   23 

26 

27 

3o 
3o 

33 
34 

0,35 

9,534 

54 

9,588 

55 

9,643 

54 

9,697 

)4    9,751 

54 

9,8o5 

53 

0,1225 

39 

4    8 

12 

16   2 

0   23 

27 

3i 

35 

o,36 

9,802 

57 

9,859 

56 

9,915 

56 

9,971 

>5  10,026 

55 

10,081 

55 

0,1296 

0,37 

10,070 

58 

10,128 

58 

10,186 

58 

10,244 

)7  io,3oi 

56 

10,357 

57 

o,i36g 

40 

4    8 

12 

16   2 

0  24 

28 

32 

36 

o,38 

io,338 

60 

10,398 

59 

10,457 

59 

io,5i6 

ig  10,575 

58 

io,633 

58 

0,1 444 

4i 

4    8 

12 

16   2 

1    25 

29 

33 

37 

0,39 

io,6o5 

62 

10,667 

6Ï 

10,728 

61 

10,78g   ( 

3o  10,849 

60 

10,90g 

60 

0,l521 

42 
43 

4    8 
4    9 

i3 
i3 

17    2 

17   2 

1  25 

2  26 

'9 
3o 

34 
34 

38 
39 

o,4o 

10,872 

63 

10,935 

63 

10,998 

63 

11,061    ( 

52     11,123 

61 

11,184 

61 

0,1600 

M 

4    9 

i3 

18    2 

2    26 

3i 

35 

4o 

0,4 1 

ii,i3o 

65 

II,2o4 

64 

11,268 

64 

11,332    f 

54  1 1 ,396 

63 

1 1 ,459 

63 

0,1681 

18   3 

32 
32 

33 
34 

36 
37 
38 
38 

4i 
4i 
42 
43 

0,42 

1 1 ,4o5 

6- 

11,4-2 

66 

11,538 

65 

ii,6o3    ( 

56  11,669 

64 

11,733 

65 

0,1764 

45 

I    ^ 

i4 

3  27 

0,43 

11,671 

68 

11,739 

68 

1 1 ,807 

67 

11,874   ( 

37  11,941 

67 

12,008 

66 

0,1849 

46 

I    9 

i4 

18    s 

3  28 

4  28 
4  29 

0,44 

11,936 

70 

12,006 

69 

12,075 

69 

12,144   ( 

59    I2,2l3 

68 

12,281 

68 

0,1936 

47 
48 

I    5 
5  10 

i4 
i4 

ig    s 

19    '' 

0,45 

12,201 

72 

12,273 

71 

12,344 

70 

i2,4i4 

71  12,485 

70 

12,555 

69 

0,2025 

49 

5  10 

i5 

20    s 

529 

34 

39 

U 

o,5o 

i3,5i8 

80 

13,598 

80 

13,678 

79 

13,757 

-9  1 3,836 

78 

i3,gi4 

78 

o,25oo 

5o 
5i 

52 

5  10 
5  10 
5  10 

i5 
i5 
16 

20    J 

5  3o 

35 

4o 

45 

0,55 

14,821 

90 

14,911 

88 

14,999 

88 

15,087 

38  15,175 

87 

15,262 

86 

o,3o25 

20    ^ 

6  3i 

36 

4i 

46 

0.60 

16.109 

98 

16,207 

98 

i6,3o5 

98 

i6,4o3 

56  16,499 

96 

i6,5g5 

9! 

o,36oo 

21    ; 

6  3i 

36 

42 

47 

0^65 

17,377 

109 

17.486 

lOT 

17,593 

107 

17,700  I 

37  17,807 

io5 

17,912 

io5 

0,4225 

53 
54 

5  11 
5  11 

16 
16 

21    ; 

732 
732 

37 
38 

42 

48 

0,70 

18,623 

119 

18,742 

118 

18,860 

118 

18,978  1 

16  19,094 

ii5 

19,209 

ii5 

0,4900 

22    : 

43 

49 

0,75 

19.841 

i3i 

■9,972 

i3o 

20,102 

128 

20,23o  I 

28  2o,358 

126 

20,484 

125 

0,5625 

55 

6  II 

17 
17 

22    ; 

8  33 

% 

44 

5o 

0,80 

21,025 

i44 

2i,i6g 

i43 

2I,3l2 

i4i 

2M53  I 

3g  2i,5g2 

1 38 

2i,73o 

i37 

o,64oo 

56 

6  11 

22    - 

.8  34 

45 

5o 

o,85 

22,l6c 

161 

22,321 

1 59 

22,480 

1 56 

22,636  I 

54  22,7go 

l52 

22,942 

i4g 

0,7225 

57 

6  II 

17 
17 

23 

g  34 
9  35 

4c 

46 

5i 

0,90 

23,398 

i85 

23,583 

179 

23,762  1 

73  23,935 

170 

24,io5 

166 

0,8100 

58 

6  12 

23 

4i 

iC 

52 

59 

60 
61 
62 
63 

6  12 

6  12 
6  12 
6  12 
6  i3 

18 

18 
18 
ig 

24 

24    - 
24 

25 
25 

Jo  35 

Î0  36 
ÎI  37 
3i  37 
52  38 

4i 

42 

43 
43 
44 

47 

48 

49 
5c 
5o 

53 

54 
55 
56 

57 

,3961 

,4050 

,4141 

,42.33 

,4325 

,4418 

â 

\    .  (r    -}-  r"  )  ^  or  r=  -f  r"^  nearly. 

19 

269                ■ 

270 

271 

272 

27 

3      27^ 

275 

276 

277 

278 

279 

280 

281 

282 

64 

6  i3 

"j 

26 

32  38 

45 

5i 

58 

I          27 

27 

2- 

7          27 

2 

7        2- 

1       28 

28 

28 

28 

28 

28 

28 

28 

65 

7  i3 

2C 

26 

3339 

4f 

53 

DO 

61 
62 

a       54 

54 

5^ 

i    54 

5 

5       5: 

)       55 

55 

55 

56 

56 

56 

56 

56 

66 

7   i3 

20 

26 

33  40 

4C 

53 
54 

3      81 

81 

8 

82 

8 

2       8; 

83 

83 

83 

83 

84 

84 

84 

85 

67 

7  i3 

20 

27 

34  40 

4- 

4     lofi 

108 

lof 

i     109 

10 

q       lie 

)     no 

no 

111 

III 

112 

112 

112 

ii3 

68 

7   i4 

20 

27 

34  4i 

48 
48 

54 
55 

5     i35 

i35 

i3f 

;   i36 

i3 

7      .3- 

1     i38 

i38 

139 

i3g 

i4o 

i4o 

i4i 

i4i 

69 

7  i4 

21 

28 

35  4i 

6     16! 

162 

16 

i     i63 

16 

4      16^ 

!     i65 

166 

166 

167 

167 

168 

169 

169 

70 

7  i4 

21 

28 

35  42 

4c, 

56 

63 

7     i8f 

189 

i9< 

)     190 

19 

I      19: 

.93 

193 

194 

195 

195 

196 

197 

'97 

80 

8  16 

24 

32     . 

io  48 

5f 

64 

72 

8       31? 

216 

21 

-     218 

21 

8         2K 

)     220 

221 

222 

222 

223 

224 

225 

226 

go 

9  18 

27 

36    . 

i5  54 

63 

72 

81 

9       34î 

243 

24 

'i     245 

24 

6     24- 

■     248 

248 

249 

2  50 

25l 

253 

253 

2  54 

100  1 

0  20 

3r 

4o 

io|  6<" 

7f 

80 

go 

TABLE  II.  —  To  find  the  time  T\  the  sum  of  the  radii  r  -f  r",  and  tlie  chord  t  being  given. 


Sum  of  the  Radii  r  -(-  r". 


Chord 

c, 


0,95 


Days  Idif. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
o,o6 
0,07 
0,08 
0,09 

0,10 
0,1 1 
0,12 
0,1 3 
0,1 4 

0,1 5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

0,3(1 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
0,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 
1,00 


0,000 
0,283 
0,567 
0,8  5o 
i,i33 

i,4i6 
1,700 
1,983 
2,266 
2,549 

2,832 

3.1 15 
3,397 
3,680 
3,963 

4,245 
4,527 
4,810 
5,092 
5,374 

5,655 
5,937 
6,219 
6,5oo 
6,781 

7,062 
7.343 
7,623 
7,903 
8.i83 

8,463 
8,743 
9,022 
g,3oi 
9,58o 

9,858 
io,i36 
io,4i4 
io,6gi 
10,96g 

1 1,245 

11,522 
11,798 
12,074 
12,349 

2,624 
13,992 

1 5,348 
16,691 
18,017 
19,324 

20,609 
21,867 
23,091 
24,271 
25,374 


0,96 


Days  idif. 


45 

46 
48 
5o 
5i 

53 
55 
56 
58 
59 

61 
62 
64 
65 
67 

69 

77 
86 

94 
io3 

!l3 
134 

1 35 
149 
i64 
191 


0,000 
0,285 
0,570 
o,854 
1, 139 

1,424 
1 ,708 
1,993 
2,278 
2,562 

2,847 
3,i3i 
3,4 1 5 
3,699 
3,984 

4,267 
4,55i 
4,835 
5,119 
5,4o2 

5;685 
5,969 

6,252 

6,534 
6,817 

7-099 

7,382 
7,664 
7,945 
8,227 

8,5o8 

8,789 
9,u70 
9,35i 
9,63: 

9'9ii 
10,191 
10,470 
10,749 
11,028 

ii,3o6 

ir,584 

II,! 

I2,i39 

I2,4i6 

1 2 ,693 
14,069 
1 5,434 
16,785 
18,120 
19,437 


,4513 


20,733  123 
22,002 1 34 


23 

24 

25 

26 
28 

3o 
3i 

32 

35 
36 

38 
38 
40 
42 
43 

45 
47 
48 

49 
5i 

53 
54 
56 
58 
59 

61 
63 
64 
66 

67 

68 
77 
85 
94 
104 
ii3 


0,97 


Days  |iiir. 


23,240 
24,435 
2  5,565 


0,000 
0,286 
0,573 
0,859 

i,i45 

i,43i 

1,717 
2,oo3 
2,290 
2,575 


3, 1 47 
3,433 
3,719 
4,004 

4,290 
4,575 
4,860 
5,i45 
5,43o 

5,7 1 5 
6,000 
6,284 
6,56g 
6,853 

7.13? 
7,420 
7,704 
7,987 
8,270 

8,553 
8,836 

9,1 

9,400 

9,682 

9>9'54 
10,245 
10,526 
10,807 
11,087 

1 1 ,367 
1 1 ,647 
11,926 

I2,2o5 

12,483 

12,761 
i4,i46 
i5,5i9 
16,879 
18,224 
19,550 

20,856 
22,1 36 
23,386 
24,596 
25,749 


,4608 


0,98 


Days  |dif. 


0,000 
0,288 
0,575 
0,86  3 
i,i5i 

1,439 
1,726 

2,Ol4 

2,3oi 

2,589 
2,876 

3,i63 
3,45i 
3,738 
4,025 

4,3 1 2 
4,599 
4,885 
5,172 
5,458 

5,745 
6,o3i 
6,3i7 
6,6o3 
6,888 

7,174 
7,459 
7,744 
8,029 
8,3i4 

8,598 
8,882 
9,166 
9,4  5o 
9,733 

10,016 
0,299 
io,58i 
10,864 
I  i,i45 

427 
1 1 ,708 
11,989 
12,270 
i2,55o 

i2,83o 

l4,233 

1 5,604 
16,973 

18,326 

19,663 

20,978 
22,269 
23,53i 
24,756 
25,927 


,4705 


0,99 


Days  lilif. 


0,000 
0,28g 

0,578 
0,868 

i,i57 

1,446 
1,735 
2,024 
2,3i3 
2,603 

2,i  _ 
3,180 

3,468 

3,757 
4,045 

4,334 
4,622 
4,910 
5,1  ~ 
5,486 

5,774 
6,062 
6,349 
6,637 
6,934 

7,211 
7,497 
7,784 
8,070 
8,356 

8,642 
8,928 
9,2i3 

9,499 
9,784 

10,068 
10,353 
10,637 
10,920 
59  11,204 


,4802 


11,487 
1 1 ,770 

I2,o53 

13,334 
12,616 

12,897 
14,398 
1 5,688 
17,065 
18,428 
19,773 

2 1 ,099 
22,401 
23,675 
24,913 
26,102 


1,00 


IJays  Idif. 


0,000 
0,291 
o,58i 
0,872 
i,i63 

1,453 

1,744 
2,o34 

2,325 

2,61 5 

2,905 
3,196 
3,486 
3,776 
4,066 

4,356 
4,646 
4,935 

5,325 

5,5i4 

5,8o3 
6,093 
6,382 
6,670 
6,959 

7,347 
7,536 
7,824 
8,112 
8,399 

8,687 
8,974 
9,261 
9,547 
9,834 

10,120 
10,406 
10,691 

10,977 
11,263 

[1,546 
11,83 

I2,Il5 

13,399 
12,683 

12,965 
14,37.' 
1 5,772 
I7,i58 
18,539 
19,883 

21,219 

32,53l 

23,817 
25,068 

26,274 
37,404 


,4901 


3o 
3o 

32 

34 
35 

37 
38 

39 
4i 
43 

44 
45 

47 

49 
5o 

52 

53 
55 
56 

57 

60 
61 
62 
63 
65 

67 
75 
83 

91 

100 
no 

119 
i3o 

i4o 
■  54 
169 
196 


1,01 


Days  |dif. 


,5000 


0,292 

o,584 
0,876 
1,168 

1,460 
1,753 
2,044 
2,336 
2,628 

2,920 
3,212 
3,5o3 
3,795 
4,086 

4,378 
4,669 
4,960 
5,25i 
5,542 

5.833 
6,123 
6,4 1 
6,704 
6,994 

7,3i 

7,574 

7,863 
8,i53 
8,442 

8,73i 
9,019 
9,3û8 

9,596 
9,884 

10,172 
10,459 
10,746 
ii,o33 
ii,3i9 

1 1 ,606 
11,89: 

12,177 
12,462 

13,747 

i3,o32 
1 4,449 
1 5,855 
17,249 
18,629 

19,99" 

21,338 
22,661 
23,957 

25,222 
26,443 
27,600 


1,02 


,ys 


0,000 
0,394 
0,587 
0,881 

1,174 

1,468 
1,761 
3  ,o54 
3,348 
2,641 

2,934 
3,228 
3,521 
3,8 1 4 
4,107 

4,399 
4,692 
4,985 
5,277 
5,569 

5,863 
6, 1 54 
6,446 

6,737 
7,029 

7,320 
7,61 1 
7,903 
8,193 
8,484 

8,774 
9,o()5 
9,354 
9,644 
•  9,934 

10,223 

IO,5l2 

1 0,800 
1 1 ,089 

11,377 

11,66' 

11,95' 
12,239 
13,526 
12,813 

1 3,099 

i4,'^23 

1 5,938 

17,34 

18,729 

20,102 

21,456 
22,789 
24,097 
25,373 
26,610 
27,789 


,5101    I  ,5202 


1,03 


Days  Idif. 


49     9,983 


0,000 
0,295 
o,5go 
0,885 
1,180 

1,475 
1,770 
2,o65 
2,359 
2,654 

2,949 
3,243 
3,538 
3,832 
4,127 

4,42 
4,71 5 
5,oog 
5,3o3 
5,597 

5,890 
6,1 84 
6,477 
6,771 
7,064 

7,356 
7,649 
7,942 
8,234 
8,526 

8,818 
9,1 10 
9,401 
9,692 


1,04 


Days  |dif. 


10,374 

io,564 
io,E 
11,144 
11,43 

11,723 
1  2 ,0 1  2 
12,30I 
12,589 
12,877 

i3,i65 
14,598 
16,020 
17,431 
18,828 
20,210 

21,573 
22,916 
24,235 
25,524 
26,775 
27,972 


i3 

i4 
16 
17 
'9 
20 

21 

23 

24 
26 

27 

29 
3o 

32 

33 

34 

36 
38 

39 
4o 
42 

43 
44 
46 
48 
49 

5i 
53 
54 
56 

57 

58 
60 
61 
63 
65 

66 
73 
82 

90 
98 

107 

117 
127 
■  37 
i48 
162 
181 


,5305 


0,000 
0,296 
0,593 
0,889 

i,i8b 

1,482 
1,778 
2,075 
2,371 
2,667 

2,963 
3,259 
3,55:' 
3,85i 
4,i47 

4,442 
4,738 
5,o33 
5,329 
5,624 

5,91g 
6,214 
6,5og 
6,804 
7,098 

7,392 
7,687 
7,981 
8,274 
8,568 

8,861 
9,1 54 
9,447 
9,740 
o,o32 

10,325 
10,617 
1 0,908 
11,200 
11,491 

1 1,781 
12,073 
12,362 

12,652 

12,942 

i3,33i 
14,671 
16,103 
17,521 
18,926 
20,317 

21,690 
23,043 
24,372 
25,672 
26,9.37 
28,153 


74 
81 

89 
98 
107 

116 

125 

i36 

1 48 
160 

177 


,5408 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 

o,oo36 
0,0049 
0,0064 
0,0081 

0,0100 
0,0121 
0,01 44 
0,0169 
0,0196 

0,0225 
o,o256 
0,0389 
o,o334 
o,o36i 

o,o4oo 

o,o44 

o,o484 

o,o52g 

0,0576 

0,0625 
0,0676 
0,072g 
0,0784 
0,084 1 

0,0900 
0,0961 
0,1024 
o,io8g 
o,n56 

0,1225 
o,  1 296 
0,1369 
0,1 444 

0,l521 

0,1600 
0,1681 
o,  1 764 
0,1849 
0,1936 

0,3025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
0,6400 
0,7225 
0,8100 
0,9025 
1 ,0000 


C- 


(  r  +  r" 


T''   -t-  r""   nearly. 


275 

f 

28 

1 

55 

3 

83 

4 

no 

«i 

,38 

6 

i65 

7 

193 

K 

2  30 

9 

248 

276 

277 

278 

279 

280 

2S1 

282 

283 

284 

385 

286 

287 

288 

28g 

290 

291 

292 

293 

28 

28 

28 

28 

28 

28 

28 

28 

28 

29 

29 

29 

29 

29 

29 

29 

29 

29 

55 

55 

56 

56 

56 

56 

56 

57 

57 

57 

57 

57 

58 

58 

58 

58 

58 

81 

83 

83 

83 

84 

84 

84 

85 

85 

85 

86 

86 

86 

86 

87 

87 

87 

88 

no 

III 

III 

112 

112 

112 

ii3 

ii3 

ii4 

ii4 

114 

ii5 

ii5 

lib 

116 

116 

117 

117 

T.38 

i3g 

i3g 

i4o 

1 40 

i4i 

i4i 

l42 

l42 

i43 

143 

144 

i44 

i45 

145 

1 46 

i46 

147 

t66 

166 

167 

167 

168 

i6q 

i6q 

170 

170 

171 

172 

172 

173 

173 

174 

175 

175 

176 

ici3 

iq4 

iq5 

iq5 

196 

Ip7 

197 

198 

iqq 

200 

300 

201 

202 

202 

2o3 

204 

204 

2o5 

•>2I 

222 

222 

223 

224 

225 

226 

326 

227 

338 

22Q 

23o 

23o 

23l 

232 

233 

234 

234 

348 

249 

25o 

25l 

252 

253 

254 

255 

256 

257 

257 

258 

25g 

260 

261 

262 

263 

264 

TABLK 

n. - 

-  To  fi 

1,1  th 

e  time 

T; 

the  sum  of  the  ra 

Hi  r 

■f 

r",  nml  ll 

e  chore 

c  tjciitff  given. 

tfuill   of  til»-'  Kadil   r-\-r". 

Prop,  parts  lur  tho  sum  ol'  tlio  Kadii.          1 

1              l-llfir.r.     >              >n<              1 

Chord 
C. 

1,05 

1,06 

1,07 

1,08 

U.iys  |dir. 

1,09 

Days  |dif. 

1,10 

I    1    2 

|0|4|3|t)|7|0 

^ 

1 
3 
3 

0 
0 

0 
0 

0 

I 
I 

0 

I 
I 
2 

I 

I 
2 

I 

1 
2 

I 
2 
2 

I 
2 
3 

Days  |dir. 

Days  |dif. 

Days  jdil'. 

Days  |dir. 

OjlKJ 

0,000 

0,000 

0,000 

0,000 

0.000 

0,000 

0,OCH)0 

o,ui 

0,298 

I 

0,299 

2 

o,3oi 

I 

o,303 

I 

O,3o3 

3 

o,3o5 

I 

0,000  1 

4 

I 

2 

2 

2 

3 

3 

4 

0,02 

0,596 

3 

0,599 

2 

0.60 1 

3 

o,6o4 

3 

o,t)07 

3 

0,610 

2 

o,ooo4 

5 

2 

2 

3 

3 

4 
4 
5 

4 
5 
6 

5 
5 
6 

o,o3 

0,893 

5 

0,898 

4 

0.903 

4 

0.906 

4 

0.910 

5 

0.915 

4 

0,01  ,ci{) 

6 

2 

2 

3 
4 

4 
4 

0,04 

iî'9' 

6 

',•197 

6 

I,203 

5 

1,208 

6 

I,2l4 

5 

1,219 

6 

0,001  () 

2 

3 

o,o5 

1.489 

n 

1,496 

7 

i,5o3 

7 

1,5 10 

7 

I,5i7 

7 

1,524 

7 

0,0025 

h 
9 

2 
2 

2 

3 

3 
4 

4 
5 

5 
5 

6 

6 

7 

7 
8 

u,oO 

i.:-«7 

8 

■.-95 

9 

1,804 

8 

1,812 

9 

1,831 

8 

1,829 

8 

0,00  36 

0,07 

2.084 

10 

2,094 

10 

2,1 04 

10 

2.114 

10 

2,124 

10 

3,i34 

9 

0,0049 

10 

2 

3 

4 

5 

6 

-. 

8 

9 

o,<* 

2.383 

II 

2.393 

13 

2,4o5 

11 

3.416 

11 

3,427 

II 

3,438 

II 

0,0064 

u 

2 

3 

4 

6 

7 

8 

9 
10 

10 

0,09 

2,680 

12 

2,692 

i3 

2,7o5 

i3 

3,718 

12 

2,73o 

i3 

2,743 

12 

0,008 1 

12 

2 

4 

5 

6 

7 

8 

II 

i3 

3 

4 

5 

7 

8 

9 

10 

12 

0,10 

2,977 

i4 

2,991 

i5 

3,006 

14 

3,030 

i4 

3,o34 

i3 

3,047 

i4 

0,0100 

i4 

3 

4 

6 

7 

8 

10 

11 

i3 

0,1 1 

3.275 

i5 

3,290 

16 

3.3o6 

i5 

3,33  1 

16 

3.33-7 

i5 

3,352 

i5 

0,01 3 1 

0,12 

3,572 

17 

3,589 

17 

3;6o6 

17 

3.633 

17 

3.640 

16 

3,656 

17 

0,01 44 

i5 

2 

3 

5 

6 

8 

9 

1 1 

12 

i4 

o,i3 

3.869 

'9 

3,888 

18 

3.906 

18 

3.934 

'9 

3.943 

18 

3:96. 

18 

0,0169 

16 

2 

3 

5 

6 

8 

10 

1 1 

i3 

i4 

o,i4 

4,167 

20 

4,18- 

19 

4,20(i 

30 

4,226 

20 

4,346 

'9 

4,265 

19 

0,0196 

17 
18 

2 
2 

3 
4 

5 
5 

7 
7 

9 
9 

10 
11 

12 
i3 

14 
14 

i5 
16 

o,i5 

4.464 

21 

4.485 

21 

4,5o6 

31 

4.527 

21 

4.548 

31 

4.56c, 

31 

0,0225 

■9 

2 

4 

6 

8 

10 

11 

i3 

i5 

17 

0,16 

4.761 

23 

4,784 

32 

4,806 

33 

4,839 

23 

4.85i 

33 

4,873 

33 

0,0  2  56 

20 

4 
4 
4 
5 

g 

8 

10 

1 2 

14 
i5 

,  r 

16 

18 

0,17 

5,o58 

24 

5.082 

24 

5,106 

34 

5,i3o 

24 

5, 1 54 

33 

5,177 

34 

0,0289 

21 

6 

8 

i3 
i3 
14 

0,18 

5.355 

25 

5,38o 

26 

5,4o6 

35 

5,43 1 

25 

5.456 

25 

5,481 

35 

o,o32.^ 

3 

1 1 

17 
18 
18 

'9 

0,19 

5,65 1 

27 

5,678 

27 

5,705 

27 

5,732 

26 

5;758 

27 

5,785 

36 

o,o36 1 

23 

3 
2 

7 
7 

9 
9 

1 1 
12 

10 
16 

20 
21 

0,20 

5,948 

28 

5,976 

28 

6,004 

29 

6,o33 

38 

6.061 

28 

6,089 

27 

o,o4oo 

24 

2 

5 

7 

10 

12 

i4 

17 

19 

22 

0,21 

6,,244 

3o 

6,274 

3o 

6,3o4 

29 

6,333 

3o 

6.363 

?9 

6,392 

39 

0,044 1 

25 

3 

5 

8 

10 

i3 

i5 

18 

20 

23 

0,22 

6.540 

32 

6,573 

3i 

6,6o3 

3T 

6.634 

3i 

6.665 

3o 

6,695 

3i 

0,0484 

26 

3 

5 

8 

10 

i3 

16 

18 

2 1 

23 

0,23 

6,837 

32 

6,869 

33 

6,902 

32 

6.934 

33 

6.967 

33 

6-999 

33 

0,0529 

27 

3 

5 

8 

1 1 

14 

16 

■9 
20 

22 

24 

35 

0,24 

7,i32 

35 

7,167 

34 

7,201 

33 

7,234 

34 

7,268 

34 

7,3o2 

33 

0,0576 

28 

3 

6 

8 

1 1 

i4 

17 

22 

0,25 

■7,42b 

36 

7,464 

35 

7,499 

36 

7,535 

35 

7,570 

35 

7,6o5 

34 

0,0625 

29 

3 

6 

9 

12 

i5 

17 

20 

23 

26 

0,26 

7,724 

37 

7. -6 1 

37 

7,798 

37 

7.835 

36 

7.871 

36 

7,907 

37 

0,0676 

3o 

3 

6 

9 

12 

i5 

18 

21 

24 

27 

0,27 

8.019 

39 

8.058 

38 

8.096 

38 

8. 1 34 

38 

8,172 

38 

8,3IO 

38 

0,0729 

3i 

3 

6 

9 

12 

16 

19 

33 

25 

28 

0,2s 

8,3i4 

4o 

8,354 

40 

8,394 

4o 

8.434 

39 

8,473 

39 

8.5 1 3 

39 

0,0784 

32 

3 

6 

10 

■  3 

16 

19 

33 

26 

29 

0,29 

8,610 

4i 

8,65 1 

4i 

8,692 

4i 

8,733 

4i 

8,774 

4i 

8,8 1 5 

40 

0,084 1 

33 
34 

3 
3 

7 
7 

10 
10 

i3 
14 

17 
17 

20 
20 

33 
34 

26 

27 

3o 
3i 

o,3o 

8,904 

43 

8,947 

43 

8,990 

42 

9,032 

43 

9,075 

42 

9,117 

43 

0,0900 

0,3 1 

9: '99 

44 

9,243 

44 

9.387 

44 

9,33i 

44 

9,375 

44 

9,419 

43 

0,0961 

35 

4 

n 

1 1 

i4 

18 

21 

25 

28 

32 

0,32 

9,493 

46 

9,539 

46 

9.585 

45 

9,63o 

45 

9,675 

45 

9,720 

45 

0,1024 

36 

4 

7 

11 

14 

18 

22 

35 

=9 

32 

0,33 

9,787 

48 

9,835 

47 

9,882 

47 

9-929 

46 

9-975 

47 

10,023 

46 

0,1089 

37 

4 

7 

11 

i5 

19 

22 

36 

3o 

33 

0,34 

10,081 

49 

io,i3o 

49 

10,179 

48 

10,227 

48 

10,375 

48 

io,323 

47 

0,1 1 56 

38 
39 

4 
4 

8 
8 

II 
12 

i5 
16 

'9 
20 

23 
23 

27 
27 

3o 
3i 

34 
35 

0,35 

10.375 

5o 

10,425 

5o 

10,475 

5o 

10.535 

5o 

10,575 

i^ 

10,624 

P 

0,1225 

4o 

4 
4 

8 

13 

16 

20 

24 

25 
25 

26 
26 

28 

32 

36 

37 
38 
39 
40 

0,36 

10.669 

5i 

10.720 

52 

10,773 

5i 

10,823 

5i 

10,874 

5i 

10,925 

5o 

0,1296 

8 
8 
9 
9 

16 

21 

33 
34 
34 
35 

0,37 

10.962 

53 

r  1 ,0 1 5 

53 

11.068 

53 

1 1. 1 20 

53 

11,173 

52 

11,225 

53 

0, 1 369 

41 

42 
43 

44 

i3 
i3 
i3 

29 

o,38 
0,39 

1 1.255 
11,547 

54 
56 

1 1 ,309 
1 1 ,6>3 

55 
56 

1 1 ,364 
11,659 

54 
56 

ii,4i8 
1 1, 71 5 

54 
55 

1 1 ,472 
1 1 ,770 

53 
55 

11.525 
11,825 

54 
55 

o,i444 

0,l53I 

4 

4 
4 

17 
17 
18 

3  I 
22 
22 

3^! 
3i 

o,4o 

11,839 

58 

1 1 .89- 

58 

11,955 

57 

12,012 

56 

12,068 

57 

12,125 

56 

0,1600 

45 

5 

9 
9 
9 
10 

i4 

18 

23 

27 

32 

36 

4i 
4i 
42 
43 
44 

0,4 1 

I2,l3l 

60 

12.1QI 

59 

I3,3  5o 

58 

i3,3o8 

58 

13,366 

58 

12,424 

58 

0,1681 

46 

5 

i4 

18 

23 

28 

32 

37 
38 

042 

12,423 

61 

13,484 

6Ô 

12,544 

60 

1 3 ,6o4 

60 

12,664 

60 

12,724 

59 

0,1764 

47 
48 

5 

i4 

19 
'9 
20 

24 

28 

33 

0,43 

12,715 

62 

12.7-7 

62 

12.839 

61 

1 3. goo 

63 

12.963 

60 

l3.022 

61 

o,i84g 

5 

i4 

34 

29 
29 

34 

38 

0,44 

1 3,006 

63 

■  3,069 

64 

i3,i33 

63 

13,196 

63 

13,359 

63 

.3,321 

63 

0,1936 

49 

5 

10 

i5 

35 

34 

39 

0,45 

13.296 

66 

1 3.362 

65 

13.427 

64 

13,491 

64 

i3,555 

64 

i3,6ig 

64 

0,2035 

5o 

5 

10 

i5 

20 

35 

3o 

35 

40 

45 

o,5o 

14.745 

73 

i4,8i8 

72 

14,890 

72 

14.963 

72 

i5.o34 

72 

i5,io6 

71 

o,25oo 

5i 

5 

10 

i5 

20 

26 

3i 

36 

4i 

46 

0,55 

i6,i83 

81 

16,264 

80 

16,344 

80 

16,424 

80 

i6,5o4 

79 

i6,583 

79 

o,3o35 

52 

5 

10 

16 

21 

26 

3i 

36 

42 

4- 

0,60 

17,610 

89 

17,699 

89 

17,788 

87 

17,875 

88 

17,963 

87 

i8,o5o 

86 

o,36oo 

53 

5 

II 

16 

21 

27 

32 

37 

4:! 

48 

o,65 

19,024 

98 

19,122 

96 

19,218 

96 

ig,3i4 

96 

19.410 

95 

i9,5o5 

94 

0,4225 

54 

5 

II 

16 

22 

27 

32 

38 

43 

49 

0,70 

20,424 

io5 

20,52g 

106 

2o,635 

io4 

20,739 

io4 

30,843 

io4 

20,947 

io3 

0,4900 

55 

6 

II 

17 

22 

38 

33 

39 

44 

5o 

0,75 

21.806 

ii5 

21.931 

ii4 

23.o35 

ii4 

22,149 

112 

23,361 

112 

22,373 

113 

0,5625 

56 

6 

II 

17 

22 

28 

34 

39 

45 

5o 

0,80 

23.16S 

125 

23,293 

124 

23,417 

133 

23,539 

123 

23,661 

131 

23,783 

121 

o,64oo 

57 

6 

1 1 

17 

23 

29 

34 

4o 

46 

5i 

0,85 

24,5o8 

i35 

24,643 

i33 

24,776 

i33 

34.90g 

l32 

25.o4i 

i3i 

25,173 

129 

0,7325 

58 

6 

12 

17 

23 

29 

35 

4i 

46 

52 

0,90 

25,820 

1 46 

25,966 

144 

26,110 

144 

26,254 

142 

26,396 

i4i 

36.537 

i4o 

0,8100 

59 

6 

12 

18 

24 

3o 

35 

4i 

47 

53 

0,95 

27.097 

i5g 

27.356 

1 57 

27,4 1 3 

1 56 

27,569 

1 54 

27,723 

I  52 

37,875 

i5i 

0,9035 

18 
18 
'9 
19 
19 

36 

37 
37 
38 
38 

1,00 

28,330 

174 

28,5o4 

172 

28,676 

.69 

28,845 

168 

29,013 

i65 

29,178 

1 64 

1 ,0000 

60 
61 
63 
63 
64 

6 
6 
6 
6 
6 

12 
12 

13 

i3 
i3 

24 
24 

25 
25 

26 

3o 
3i 
3i 

32 
32 

42 
43 
43 
44 
45 

48 
49 

5o 

54 
55 
56 

57 
58 

.5513 

,5618 

,5725 

,5832 

,5941  1 

,6050 

c" 

i  .  (r  +  r"«)  or  r"  +  r""    nearly. 

294 

295 

296 

297 1     29^ 

299 

3oo 

3oi 

302 

3., 3 

3o4 

3o5 

J  J 







— 





— 

— 

— 



65 

7 

i3 

30 

26 

33 

39 

46 

52 

5g 

I 

=9 

3o 

3o 

3< 

)         3c 

)        3o 

3o 

3o 

3o 

3c 

3o 

3i 

66 

7 

1 3 

30 

26 

33 

4o 

46 

53 

59 

2 

59 

59 

59 

5< 

,        6c 

)        60 

60 

60 

60 

61 

61 

61 

67 

7 

i3 

30 

27 

34 

4o 

47 

54 

65 

3 

88 

89 

89 

8( 

i        8ç 

)        90 

!   90 

90 

91 

91 

9' 

92 

68 

7 

i4 

30 

27 

34 

4i 

48 

54 

61 

4 

118 

118 

118 

lie 

)       II' 

1      120 

120 

120 

121 

121 

122 

122 

6g 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

5 

l47 

1 48 

1 48 

i4( 

)      i4( 

)      i5o 

i5o 

i5i 

i5i 

l53 

l52 

1 53 

6 

176 

177 

178 

17' 

1      17c 

)       '79 

180 

181 

181 

182 

182 

i83 

70 

7 

i4 

21 

28 

35 

42 

49 

56 

63 

7 

206 

207 

207 

20f 

i          30( 

)       2og 

210 

211 

211 

212 

2l3 

3l4 

80 

8 

16 

24 

32 

4o 

48 

56 

64 

72 

8 

235 

236 

237 

23 

i          23f 

;      239 

240 

241 

242 

242 

343 

244 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

9 

265 

266 

266 

26 

-          26( 

5      369 

370 

271 

272 

273 

274 

375 

ICX) 

10 

20 

3o 

4o 

5o 

60 

70 

80 

_9o 

a6 


TABLE  II. 

—  To  find  the  time  T 

the  sum  0 

f  the  radii 

■  +  .", 

and  the  cb 

51-d  c 

being 

given. 

Sum   of  the  Itadii  r  -)-  r".                                                                                                            i 

Chord 
C. 

1,11 

1,12 

1,13 

1,14 

1,15 

1,16 

1,17 

1,18 

1,19 

1,20 

Duys  |dif. 

Days  |dif. 

Days  |dil'. 

Days  |dir. 

Days  |clif. 

Kays  |dil'. 

Days  |ilif. 

Days  Idif. 

Days  |.lif. 

Days  |dif. 

0,00 

0,000 

0,000 

OjOOC» 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

u,uooo 

0,01 

0,3o6 

2 

o.3o8 

I 

0,309 

I 

o,3io 

2 

0,3l2 

I 

o,3l3 

I 

0,3l4 

2 

o,3l6 

I 

o,3i7 

I 

0,3l8 

2 

0,0001 

0,02 

0,612 

3 

0,61 5 

3 

0,618 

3 

0,621 

2 

0,623 

3 

0,626 

3 

0,629 

2 

o,63l 

3 

o,634 

3 

0,637 

2 

o,ooo4 

o,o3 

0,919 

4 

0,923 

4 

0,927 

4 

0,931 

4 

0,935 

4 

0,939 

4 

0,943 

4 

°'947 

4 

0.951 

4 

0,955 

4 

(.,,0009 

o,o4 

1,225 

5 

I,23o 

6 

1,236 

5 

1,241 

6 

1,347 

5 

1,253 

6 

1,2  58 

5 

1,263 

5 

1,268 

6 

1,274 

5 

0,0016 

o,o5 

1, 53 1 

7 

1,538 

7 

1,545 

7 

1.552 

6 

1,558 

7 

1,565 

7 

1,572 

7 

1,579 

6 

1,585 

7 

1 ,592 

7 

0,0025 

0,06 

1.837 

8 

1,845 

9 

1.854 

8 

1,862 

8 

1,870 

8 

1,878 

8 

1,886 

8 

1,894 

8 

1 ,902 

8 

1,910 

8 

o,oo36 

0,07 

2,143 

10 

2;i53 

10 

2.i63 

9 

2,173 

10 

3,183 

9 

2,191 

9 

3,200 

10 

2,310 

9 

2,219 

10 

2,229 

9 

0,0049 

o,oS 

2,449 

II 

2,460 

II 

2.471 

1 1 

2,482 

II 

2,493 

II 

2,5o4 

II 

2,5i5 

10 

3,525 

II 

2,536 

1 1 

2,547 

10 

(.1,0064 

0,09 

2,755 

i3 

2,768 

12 

2,780 

12 

2,792 

i3 

2,8o5 

12 

3,817 

12 

2,829 

12 

2,84 1 

13 

2,853 

12 

3,865 

12 

0,0081 

0,10 

3.061 

i4 

3.075 

14 

3,089 

i3 

3,102 

i4 

3,116 

i4 

3,i3o 

i3 

3,143 

1 3 

3,i56 

i4 

3,170 

i3 

3,i83 

i3 

0,0 1 00 

0,1  I 

3.367 

i5 

3.382 

i5 

3,397 

i5 

3,4i2 

i5 

3,427 

i5 

3,443 

i5 

3,457 

i5 

3,472 

i5 

3,487 

i4 

3,5oi 

i5 

U,012I 

0,12 

3,673 

17 

3,690 

16 

3,706 

16 

3.723 

17 

3,739 

16 

3,755 

16 

3,771 

16 

3,787 

16 

3,8o3 

16 

3,819 

16 

0,0  [44 

0,1 3 

3.979 

18 

3.997 

17 

4.014 

18 

4,o32 

18 

4.o5o 

18 

4,068 

17 

4,o85 

18 

4,io3 

17 

4,120 

17 

4,i37 

17 

0,0  [69 

0,1 4 

4,284 

20 

4,3o4 

'9 

4,323 

19 

4,342 

19 

4,36i 

19 

4,38o 

■9 

4,399 

19 

4,418 

18 

4.436 

19 

4,455 

'9 

0,0196 

0,1 5 

4,590 

21 

4,611 

20 

4,63 1 

21 

4,652 

20 

4,672 

21 

4,693 

20 

4,71 3 

30 

4,733 

30 

4,753 

20 

4,773 

20 

0,0225 

0,16 

4,095 

23 

4.918 

22 

4.940 

21 

4,961 

22 

4.983 

22 

5,oo5 

21 

5,026 

22 

5,048 

21 

5,060 

22 

5,09] 

21 

o,o256 

0,17 

5,201 

23 

5.224 

24 

5,248 

23 

5,271 

23 

5.394 

23 

5,3 1 7 

23 

5,340 

23 

5,363 

23 

5,38b 

22 

5,408 

23 

0,0389 

0,18 

5,5o6 

25 

5,53i 

25 

5.556 

24 

5.58o 

25 

5,6o5 

24 

5,629 

25 

5,654 

24 

5,678 

24 

5,702 

34 

5,726 

24 

0,0834 

0,19 

5,811 

27 

5,838 

26 

5,864 

26 

5,890 

26 

5,916 

25 

5,941 

26 

5,967 

26 

5,993 

25 

6,018 

35 

6,043 

26 

o,o36i 

0,30 

6.116 

28 

6.144 

27 

6.1 71 

28 

6,19g 

27 

6,236 

27 

6,253 

27 

6,280 

27 

6,3o7 

27 

6,334 

27 

6,36i 

26 

o,o4oo 

0,21 

6,421 

29 

6.45o 

29 

6.479 

29 

6.5o8 

29 

6,537 

28 

6,565 

28 

6,593 

29 

6,622 

28 

6,65o 

28 

6,678 

28 

0,044 1 

U,22 

6,726 

3o 

6,756 

3i 

6,787 

3<. 

6.817 

3o 

6,847 

3o 

6,877 

3o 

6,907 

29 

6,936 

3o 

6,966 

29 

6.995 

29 

o,o484 

0,23 

7,o3i 

3i 

7,062 

32 

7,094 

33 

7,126 

3i 

7,1  57 

3i 

7,188 

3i 

7,219 

3i 

7,25û 

3i 

7,281 

31 

7,3 1 2 

3i 

o,o52g 

0,24 

7,335 

33 

7,368 

33 

7,401 

33 

7,434 

33 

7,467 

33 

7,5oo 

32 

7,532 

33 

7,565 

32 

7,597 

32 

7,639 

32 

0,0576 

0,25 

7,639 

35 

7,674 

35 

7,709 

34 

7,743 

34 

7,777 

M 

7,811 

34 

7,845 

34 

7,879 

33 

7,912 

34 

7,946 

33 

0,0625 

0,26 

7,944 

36 

7.980 

36 

8.oi(i 

35 

8.o5i 

36 

8,087 

35 

8,122 

35 

8,i57 

35 

8,192 

35 

8,227 

55 

8,362 

35 

0,0676 

0,27 

8,248 

37 

8.285 

37 

8,322 

37 

8.359 

37 

8,396 

37 

8,433 

37 

8,470 

36 

8,5o6 

36 

8,542 

37 

8,579 

36 

0,0729 

0,28 

8,55i 

39 

8:590 

39 

8,629 

38 

8,667 

39 

8,706 

38 

8,744 

38 

8,782 

38 

8,820 

37 

8,857 

38 

8,895 

37 

0,0784 

0,29 

8,855 

40 

8,895 

40 

8,935 

40 

8,975 

40 

9,01 5 

40 

9,o55 

39 

9,094 

39 

9,i33 

39 

9.172 

39 

9,211 

39 

o,o84i 

o,3o 

9>i59 

4i 

9,200 

42 

9.242 

4i 

9,283 

4i 

9,334 

4i 

9,365 

41 

9,406 

40 

9,446 

4i 

9,487 

40 

9,527 

4o 

0,0900 

0,3 1 

9,462 

43 

9:505 

43 

9,54»' 

43 

9-591 

42 

9,633 

42 

9.675 

42 

9,717 

42 

9.759 

43 

g,8oi 

42 

9,843 

4i 

0,0961 

0,32 

9,765 

44 

9,809 

45 

9,854 

44 

9,898 

44 

9,94? 

43 

9,985 

44 

10,029 

43 

10,072 

43 

io,ii5 

43 

io,i58 

43 

0,1024 

0,33 

10,068 

46 

io,ii4 

45 

10,1 59 

46 

IO,3o5 

45 

I0,250 

45 

10,395 

45 

io,34o 

45 

[o,385 

A4 

10,429 

45 

10,474 

44 

o,io8g 

0,34 

10,370 

48 

10,418 

47 

10,465 

4i 

IO,5l2 

47 

10,559 

46 

io,6o5 

46 

I  o,65 1 

46 

10,697 

46 

10,743 

46 

10,789 

45 

0,11 56 

0,35 

10,673 

49 

10.722 

48 

10,770 

49 

10.819 

48 

10,867 

48 

10,915 

47 

10,963 

48 

n,oio 

47 

1 1  ,o57 

47 

11,104 

47 

0,1225 

o,36 

10,975 

5o 

11,025 

5o 

11,075 

5o 

n,i25 

5o 

r  1,175 

49 

n,224 

49 

11,273 

49 

11,322 

48 

11,370 

49 

11,419 

48 

0,1296 

0,37 

11,277 

52 

11.329 

5i 

1 1 ,38o 

5i 

n.43[ 

5i 

11,482 

5i 

11,533 

50 

11,583 

5i 

11,634 

5o 

11,684 

49 

11,733 

5o 

o,i36g 

o,38 

[  1 ,579 

53 

11.632 

53 

1 1 ,685 

52 

.1:737 

53 

1 1 .790 

52 

11,842 

53 

11,894 

5i 

11,945 

52 

11,997 

5i 

12,048 

5i 

o,i444 

0,39 

1 1 ,880 

55 

11.935 

54 

1 1 ,989 

54 

I2,o43 

54 

1 3 ,097 

53 

1 2 , 1 5o 

54 

12,204 

53 

13,357 

52 

12,809 

53 

12,362 

52 

[i,[52I 

o,4o 

12,181 

56 

12,237 

56 

12.293 

55 

12.348 

56 

i2,4o4 

55 

12,459 

54 

i2,5i3 

55 

12,568 

54 

12,622 

54 

12,676 

54 

0,1600 

0,4 1 

12.482 

58 

12.540 

57 

12,597 

57 

12,654 

56 

[2,710 

57 

12,767 

56 

13,833 

56 

12,879 

55 

12,934 

56 

12,990 

55 

n,i68i 

0,42 

12:783 

59 

12.842 

58 

12.900 

59 

i2.95[. 

58 

l3,OI-7 

58 

13,075 

57 

1 3, 1 32 

57 

13,189 

57 

1 3,246 

57 

i3,3o3 

57 

0,1764 

0,43 

i3.o83 

61 

i3,i44 

60 

i3.2o4 

"■9 

13.263 

60 

[3,333 

59 

1 3,382 

59 

T  3,441 

59 

i3,5oo 

58 

i3,558 

58 

i3,6i6 

58 

o,i84g 

0,44 

1 3,383 

62 

1 3,445 

62 

i3,507 

(11 

1 3,568 

61 

13,629 

60 

13,689 

61 

i3,75o 

60 

i3,8io 

60 

18,870 

59 

18,929 

59 

0,1986 

0,45 

1 3,683 

63 

1 3,746 

63 

13.809 

63 

13,87? 

62 

13.934 

62 

1 3, 096 

63 

i4,o58 

62 

l4,130 

6, 

i4,i8i 

61 

14,242 

61 

0,2025 

o,5o 

1 5, 1 77 

70 

1 5,247 

71 

i5.3i8 

70 

1 5.388 

70 

1 5,458 

69 

1 5,527 

69 

i5,5g6 

C9 

1 5,665 

68 

15,733 

68 

1 5,801 

68 

o,25oo 

0,55 

16.662 

78 

i6,74o 

78 

i6.8iK 

77 

16.895 

77 

16.973 

77 

17,049 

77 

17,126 

75 

17,201 

76 

17,277 

75 

17,352 

75 

o,3o25 

0,60 

i8,i36 

86 

18,222 

86 

i8,3o8 

85 

18,393 

85 

18,478 

84 

i8,563 

84 

[8,646 

83 

18,729 

83 

18,812 

87 

i8,8g5 

83 

o,36oo 

0,65 

19,599 

94 

19,693 

94 

19.787 

93 

19,880 

92 

19-972 

92 

20,064 

92 

20,1 56 

91 

20,347 

90 

20,337 

91 

30,438 

89 

0,4225 

0,70 

2i,o5o 

102 

2I,l52 

lOI 

21,253 

lOI 

21,354 

lOI 

21,455 

100 

21,555 

99 

31,654 

99 

21,753 

98 

2 1, 85 1 

98 

21,949 

97 

0,4900 

0,75 

22,485 

no 

22,595 

1 10 

22,705 

no 

22,8l5 

108 

22,933 

109 

23,o33 

107 

23,139 

107 

23,246 

!06 

23,352 

106 

23,458 

io5 

o,5635 

0,80 

23,903 

119 

24.022 

i'9 

24,i4i 

118 

24.259 

117 

24,376 

117 

24,493 

116 

24,609 

(i5 

24,724 

ii5 

24,889 

i-iA 

34.053 

ii3 

o,64oo 

0,85 

25,3oi 

I '9 

25:430 

12S 

25.558 

127 

2  5,685 

127 

25,812 

135 

25,937 

125 

36,062 

124 

36,186 

133 

36,309 

123 

26,433 

121 

0,7225 

0,90 

26.677 

1 39 

26,816 

1 38 

26.954 

■37 

37.091 

1 36 

27,227 

i35 

27,362 

1 34 

27,496 

1 33 

37,639 

l32 

27,761 

l32 

27,893 

i3o 

0,8100 

0,95 

28.026 

i5o 

28,176 

■49 

28,:325 

1 47 

28,472 

146 

38,618 

i45 

28,763 

i44 

28,907 

i43 

39,o5o 

142 

29,192 

i4i 

29,333 

i4o 

0,9025 

I, ou 

:9,342 

162 

29.504 

161 

29,665 

.59 

29.82Z 

I  57 

29.981 

1 56 

3o,i37 

i55 

30,293 

[54 

30.446 

I  52 

30.598 

r5i 

3o,749 

i5o 

1 ,0000 

,6161 

,6272 

,638.5 

,6498 

,6613 

,6728 

,6845 

,6962 

,7081 

,7200 

c2 

4  .  (  r  +  !■"  ,=  or  )-'  -)-  r"'   nf:irly.                                         | 

3oo 

3oi 

302 

3o3 

3o4 

3o5 

3o6 

3o7 

3o8 

309 

3[o 

3ii 

3l2 

3i3 

3i4 

3i5 

3i6 

3o 

3o 

3o 

3o 

3o 

3i 

3i 

3i 

3i 

3i 

3i 

3i 

3i 

3i 

3i 

32 

32 

fio 

60 

60 

61 

61 

61 

61 

61 

62 

62 

62 

62 

63 

63 

63 

63 

63 

QO 

9" 

91 

9' 

91 

92 

92 

92 

92 

93 

93 

93 

94 

94 

94 

95 

gb 

120 

120 

121 

121 

122 

133 

122 

123 

123 

134 

134 

124 

125 

125 

126 

126 

130 

i5o 

i5i 

i5i 

l52 

l52 

1 53 

1 53 

1 54 

1 54 

1 55 

1 55 

i56 

1 56 

1 57 

1 57 

1 58 

1 58 

I  So 

181 

181 

182 

182 

i83 

184 

184 

i85 

i85 

186 

187 

187 

188 

188 

189 

I  go 

210 

211 

21 1 

212 

2l3 

2l4 

214 

2l5 

216 

216 

217 

218 

218 

219 

220 

221 

221 

240 

241 

242 

242 

243 

244 

245 

246 

246 

247 

248 

249 

2  50 

2  5o 

35l 

252 

253 

270 

271 

272 

273 

374 

275 

275 

376 

277 

278 

279 

280 

381 

282 

283 

284 

284 

TABLE  11.  —  To  liml  llie  time  T\  the  sum  of  the  radii  r-|-r",  and  tlie  cliord  c  being  c;iven. 


Sum  ui'  tlie  Radii  r -\- r' 


Chord 
C. 

0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
o,oC 
0,07 
0,08 
0,09 

0,10 
0,1 1 
0,13 
o,i3 
0,1 4 

0,1 5 
0,16 
0,1- 
0,1  S 
o,ig 

0,30 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
o,3g 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
0,65 
0,70 

0,75 
0,80 
o,85 
0,90 
0,95 
1,00 


\^i 

1 

!).,)« 

idif. 

t»,tKH) 

t>,3-.>ti 

I 

i>,()Jy 

3 

0,919 

4 

i>J7y 

5 

■.599 

6 

1,0  tb 

« 

2.a3t 

q 

2,55- 

1 1 

2,87: 

12 

3,19(1 

i4 

3,5 16 

14 

3,835 

16 

4,1 54 

18 

4,4:'4 

18 

4.-C.3 

20 

3,1  ij 

21 

5,43 1 

22 

5,-50 

24 

6,069 

25 

6,38- 

27 

6,706 

28 

-.024 

2Q 

7.343 

3o 

-,661 

32 

7,979 

33 

8,29- 

34 

8,61 5 

35 

8.932 

37 

9,2Do 

38 

9,567 

40 

9,884 

4i 

10,201 

Ai 

io,5i8 

44 

io,834 

46 

1  i,i5i 

46 

1 1 ,46- 

48 

11,-83 

49 

12,099 

bi 

i3,4i4 

D2 

i2,73o 

53 

1 3,045 

55 

i3,36o 

56 

13,674 

58 

13,988 

60 

i4.3o3 

60 

15,869 

67 

'7>427 

7^ 

18,977 

82 

20.317 

Kq 

22,o46 

97 

23,563 

io5 

25,066 

ii3 

26,553 

122 

28,023 

i3o 

29,473 

.3q 

30,899 

149 

,73S 

Î1 

1,-22 

Dhvs 

d.r. 

o,OOC: 

0,321 

I 

0,642 

3 

o,9(>3 

4 

1,284 

5 

i,6<:.5 

-, 

1 ,926 

8 

2,24- 

9 

2,568 

10 

2,889 

12 

3,aio 

i3 

3,53o 

i5 

3,S5i 

16 

4,173 

17 

4,.-i92 

19 

4,8 1 3 

iq 

5,1 33 

21 

5,453 

23 

5,774 

23 

6,094 

25 

6,4 14 

26 

6,734 

27 

7,o53 

3q 

7,373 

3o 

7.693 

3i 

8,012 

33 

8,33i 

35 

8,65o 

36 

8,q6Q 

37 

9,28» 

39 

9,607 

4o 

9,925 

41 

10,244 

43 

10,562 

44 

10,880 

45 

11,197 

47 

11,313 

48 

11,832 

5o 

I2,l5o 

5o 

12,466 

52 

12,783 

53 

i3,ioo 

54 

i3,4i6 

56 

i3,732 

57 

i4,o48 

58 

i4,363 

60 

1 5,936 

67 

17,503 

74 

19,059 

81 

20,606 

8q 

22,l43 

96 

23,668 

io4 

25,179 

112 

26,675 

120 

28,153 

I2q 

29,612 

1 38 

3i,o48 

1 48 

,74^ 

12 

1,23 


Uuys  |djr. 

o,ix)o 
0,322 

0,645 

(.1,96- 

1,289 


1,612 

1 ,934 

2,256 

2,578 
2,901 

3,333 

3,545 

3,86- 
4,189 
4,5ii 

4,833 
5,i54 
5,476 

5,797 
6,119 

6,44o 
6,761 

7,083 
7,4o3 
7,724 

8,045 
8,366 
8,686 
9,006 
g,32 

9,647 
9,966 
10,286 
1 0,606 
10,925 

11,344 
11,563 
11,882 
12,200 
i2,5i8 

12,836 
i3,i54 
1 3,472 
13,789 
i4,io6 

14,423 
1 6,oo3 
17,576 
19,140 
20,695 
22,239 

23,772 
25,291 
26,795 
28,282 
39,750 
31,196 


,7565 


1,24 


Duyâ  |dit'. 


0,000 
0,324 
0,647 
0,97 1 
1,295 

1,618 
1,942 
2,265 
2,589 
2,9 

3,236 
3,559 
3,882 
4,206 
4,529 

4,853 
5,175 
5,498 
5,821 
6,144 

6,4C6 

6,789 
7,1 1 1 
7,434 
7,756 

8,078 
8,400 
8,723 
9,043 
9,36- 

9,686 
10,007 
10,328 
10,649 
10,970 

1 1 ,290 
11,610 
11,930 

I2,25o 


13,889 
13,209 
1 3,528 
1 3,846 

i4,i65 

1 4,483 
16,070 
i7,65o 
19,321 
20,784 
22,335 

23,875 

25,402 

26,915 
28,410 

9,8 
3 1,343 


,7688 


1,25 


UiijS  |dil'. 


0,000 

0,325 
o,65o 
0,975 
1 ,3oo 

1,625 
1,950 

2,274 
2,599 

2,924 

3,349 
3,574 
3,898 

4,323 

4,547 

4,872 
5,196 

5,520 
5,844 
6,168 

6,492 
6,816 

7,i4o 
7,464 
7,787 

8,111 
8,434 
8,757 
9,080 
9,4o3 

9,725 
10,048 
10,370 
1 0,692 
1 1, 014 

11,336 
11,658 
11,979 

I2,300 
13,621 

12,942 
1  3,263 

1 3,583 
i3,qo3 

l4,223 

14,543 
i6,i37 
17,724 
19,302 
30,873 

23,43l 

23,978 
35,5i3 
27.034 
28,538 
3o,o24 
3i,488 


i3 
i4 
16 

17 
18 

■9 
21 
22 

24 

25 

26 
28 

29 
3o 
3i 

32 

34 
35 
37 
38 

40 
40 
42 
44 
45 

46 

47 

49 
5o 

52 

53 
54 
55 

57 
58 

59 
66 

73 
80 
87 
95 

io3 
no 
n8 
126 
i35 
i45 


,7813 


1,26 


Daya  |dit'. 


0,000 
0,326 

o,653 

0,979 

i,3o5 

i,63i 

1,957 
2,384 
2,610 
3,936 

3,262 
3,588 
3,914 
4,240 
4,565 

4,6 

5,3l7 

5,542 

5,868 

6,193 

6,5i8 
6,844 
7,169 
7,494 
7,818 

8,i43 
8,468 
8,793 
9,"7 
9,441 

9,765 
10,08b 

10,4 13 
10,736 

1 1 .059 

11,382 
1 1 ,7o5 
12,028 
i2,35o 
13,673 

12,995 
!3,3i7 
i3,638 
i3,g6o 
14,281 

1 4.60  3 
i6,2o3 

17,797 
19,382 
20,959 
22,526 

24,081 
25,633 

37,l52 

28,664 

3o,i59 
3 1,633 


33 
25 

26 

27 
28 
3o 

32 

33 
34 
35 
36 

37 

39 
4i 
43 
43 
44 

46 
47 
48 
5o 
5i 

52 

53 
55 
5f) 
58 

59 
66 

73 
80 
87 
94 

102 
no 
118 
127 
i35 
1 44 


,7938 


0,0000 
0,0001 

o,ooo4 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
o,t)o()4 
0,0081 

0,0100 

0,<H2I 

0,01 44 
0,0169 
0,0196 

0,0235 
o,o256 
0,0289 
o,o324 
o,o36i 

o,o4oo 
o,o44  i 
0,0484 
0,0^29 
0,0570 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

o,oyoo 
0,0961 
0,1024 
0,1089 
0,1 1 56 

0,I225 

0,1296 
o,  1 369 
0,1444 
0,1 52  I 

0,l6l)0 

o,  1 68 1 
o,  1 7(i4 
0,1849 
0,1936 

0,2025 
0,2  5oo 
o,3o25 
o,36oo 
0,4225 
o,49"o 


Ï  •  (r  -}-  r'2)  or  r=  -f  r"  -  nearly. 


3i7 

3i8 

3ig 

320 

331 

322 

323 

354 

325 

326 

327 

32 

32 

33 

32 

32 

32 

32 

32 

33 

33 

33 

63 

64 

64 

64 

64 

64 

65 

65 

65 

65 

65 

95 

q5 

q6 

q6 

q6 

97 

97 

97 

98 

q8 

q8 

127 

127 

128 

128 

128 

l2q 

I2q 

i3o 

i3o 

i5o 

i3i 

l5q 

:5q 

160 

1 60 

161 

161 

162 

162 

i63 

i63 

164 

190 

'9' 

19' 

192 

iq3 

iq3 

194 

194 

195 

196 

196 

222 

223 

223 

224 

225 

225 

226 

227 

228 

228 

239 

254 

254 

255 

2  56 

257 

258 

258 

239 

260 

261 

263 

285 

286 

287 

288 

289 

390 

391 

392 

293 

393 

394 

1' 

"1' 

Piirlslor  tlif 

sum  of 

ll.c 

Kai 

li. 

1  |2 

3 

4  1  5  1  6  1  7  1  8 

9 

I 

0 

0 

0 

0 

I 

1 

I 

I 

I 

3 

0 

0 

I 

1 

I 

I 

1 

2 

2 

3 

0 

1 

1 

1 

2 

2 

2 

2 

3 

4 

0 

I 

1 

2 

2 

2 

3 

3 

4 

5 

1 

2 

2 

3 

3 

4 

4 

5 

6 

1 

2 

2 

3 

4 

4 

5 

5 

7 

' 

2 

3 

4 

4 

5 

6 

6 

8 

3 

2 

3 

4 

5 

6 

6 

7 

9 

3 

3 

4 

5 

5 

6 

7 

8 

10 

3 

3 

4 

5 

6 

7 

8 

q 

1 1 

2 

3 

4 

6 

7 

8 

q 

10 

1  2 

2 

4 

5 

6 

8 

10 

1 1 

i3 

3 

4 

5 

7 

8 

q 

10 

12 

i4 

3 

4 

6 

7 

8 

10 

1 1 

i3 

i5 

2 

3 

5 

6 

8 

q 

1 1 

12 

i4 

16 

3 

3 

5 

6 

8 

ll.» 

1 1 

i3 

i4 

17 

3 

3 

5 

7 

q 

10 

12 

14 

i5 

18 

2 

4 

5 

7 

q 

1 1 

i3 

14 

lb 

19 

2 

4 

6 

8 

10 

I  1 

i3 

i5 

17 

20 

2 

4 

6 

8 

10 

1  2 

i4 

i( 

18 

21 

2 

4 

6 

8 

1 1 

i3 

i5 

17 

iq 

22 

2 

4 

7 

q 

1 1 

i3 

i5 

18 

20 

23 

2 

5 

7 

q 

12 

i4 

16 

18 

21 

34 

2 

5 

7 

10 

12 

i4 

17 

'9 

22 

25 

3 

5 

S 

10 

i3 

i5 

18 

21) 

23 

26 

3 

5 

8 

10 

i3 

16 

18 

21 

23 

27 

3 

5 

8 

1  1 

i4 

16 

iq 

22 

24 

28 

3 

6 

8 

1 1 

14 

17 

20 

22 

25 

29 

3 

6 

9 

12 

i5 

17 

20 

23 

26 

3o 

3 

6 

9 

q 

12 

i5 

18 

21 

24 

27 

3i 

3 

6 

12 

16 

iq 

32 

25 

28 

33 

3 

6 

10 

i3 

16 

iq 

2  2 

26 

2q 

33 

3 

10 

i3 

'7 

20 

33 

36 

3o 

34 

3 

7 

10 

14 

17 

20 

24 

27 

il 

35 

4 

7 

1 1 

i4 

18 

31 

35 

38 

32 

36 

4 

7 

1 1 

14 

18 

22 

25 

29 

32 

37 

4 

7 

1 1 

i5 

iq 

22 

26 

30 

ii 

38 

4 

8 

I  1 

i5 

iq 

33 

27 

3o 

i4 

39 

4 

8 

12 

16 

30 

23 

27 

3i 

35 

40 

4 

8 

13 

16 

20 

34 

28 

32 

36 

4i 

4 

8 

12 

16 

21 

25 

2q 

33 

37 

42 

4 

t 

l3 

17 

31 

35 

2q 

M 

38 

4J 

4 

9 

i3 

17 

32 

26 

3o 

M 

iq 

44 

4 

9 

i3 

18 

32 

26 

3i 

35 

40 

45 

5 

9 

i4 

18 

23 

27 

33 

36 

4i 

46 

3 

q 

i4 

18 

33 

28 

32 

37 

41 

47 

5 

q 

i4 

iq 

24 

28 

iJ 

38 

42 

48 

5 

10 

14 

iq 

24 

2q 

M 

38 

43 

49 

'j 

10 

13 

20 

23 

29 

M 

39 

44 

5o 

5 

10 

i5 

20 

25 

3o 

35 

4o 

45 

5i 

5 

10 

i5 

20 

26 

3i 

36 

4i 

46 

52 

5 

10 

16 

21 

26 

3i 

36 

42 

47 

53 

5 

1  1 

16 

21 

27 

32 

37 

42 

48 

54 

5 

1 1 

16 

22 

27 

32 

38 

4à 

49 

55 

6 

I  I 

17 

22 

28 

33 

3q 

44 

5o 

56 

6 

1 1 

>7 

22 

38 

34 

3q 

45 

5o 

57 

6 

1  I 

17 

23 

3q 

M 

4o 

46 

5i 

58 

6 

12 

17 

23 

2q 

35 

4i 

46 

52 

59 

6 

12 

18 

24 

3o 

35 

4i 

47 

53 

60 

6 

1  3 

18 

24 

3o 

36 

42 

48 

54 

61 

6 

13 

18 

24 

3i 

37 

43 

4q 

55 

62 

6 

13 

iq 

25 

3i 

37 

43 

5o 

56 

63 

6 

i3 

iq 

25 

32 

38 

44 

5o 

57 

64 

6 

i3 

19 

26 

32 

38 

45 

5i 

58 

65 

-, 

i3 

20 

26 

33 

3q 

46 

53 

5q 

66 

7 

i3 

20 

26 

33 

4o 

46 

53 

5q 

67 

7 

i3 

20 

27 

34 

4o 

47 

54 

60 

68 

i4 

30 

27 

M 

4i 

48 

54 

61 

69 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

70 

7 

i4 

21 

28 

35 

42 

49 

56 

63 

80 

8 

16 

24 

33 

4o 

48 

56 

64 

72 

qo 

q 

18 

27 

36 

45 

54 

63 

72 

81 

100 

Id 

30 

3o 

40 

5o 

61. 

70 

80 

90 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-f-r",  and  the  chord  c  being  given. 


Sum  of  the  radii  r-f-î-'.                                                                                                                  1 

Cliord 
C. 

1,27 

1,28 

1,29 

1,30 

1,31 

1,32 

1,33 

1,34 

1,35 

1,36 

_l 

Days  |ilif. 

Day»  \A\f. 

Days  Iclir. 

Days  |dir. 

Days  |dil'. 

Uaysldif. 

Days  |dir. 

Days  \, 

if. 

Days  |dif. 

Days  Idif.    1 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

),0000 

o,oi 

0,328 

1 

0,329 

I 

o,33o 

I 

0,33l 

2 

0,333 

I 

0,334 

I 

0,335 

I 

o,336 

2 

o,33& 

I 

0,339 

1 

1,0001 

0,02 

o,655 

3 

o,658 

2 

0,660 

3 

o,663 

2 

o,665 

3 

0,668 

2 

0,670 

3 

0,673 

2 

0,675 

3 

0,67b 

1 

J  ,0004 

o,o3 

0,983 

4 

0,987 

3 

0,990 

4 

0,994 

4 

0,998 

4 

1,002 

4 

1 ,006 

3 

[,009 

4 

i,oi3 

4 

1,017 

A 

1,0009 

o,o4 

I,3lO 

5 

i,3i5 

5 

1,320 

6 

1,326 

5 

i,33i 

5 

1,336 

5 

1,341 

5 

1,346 

5 

i,35i 

5 

1 ,356 

5 

0,0016 

o,o5 

1,638 

6 

1,644 

7 

i,65i 

6 

1.657 

6 

1,663 

7 

1,670 

6 

1 ,676 

6 

[,682 

7 

1,689 

6 

1,695 

6 

0,0026 

0,06 

i,g65 

8 

1 ,973 

8 

1,981 

7 

1,988 

8 

1.996 

8 

2,oo4 

7 

2,011 

8 

2,oig 

7 

3,026 

8 

3,o34 

7 

i,oo36 

0,07 

2,293 

9 

2,302 

9 

2,3ll 

9 

2,320 

8 

2,328 

9 

2,337 

9 

2,346 

9 

2,355 

9 

2,364 

9 

2,373 

8 

3,0049 

0,08 

2,620 

10 

2,63o 

1 1 

2,641 

10 

2,65 1 

10 

2,661 

10 

2,671 

10 

2,681 

10 

2,691 

10 

2,701 

10 

2,711 

ii> 

},oo64 

0,09 

2,947 

12 

2.959 

12 

2,971 

11 

2,982 

12 

2.994 

11 

3,oo5 

i[ 

3,016 

12 

3,028 

11 

3,o39 

11 

3,o5o 

" 

0,0081 

0,10 

3,275 

i3 

3,388 

12 

3,3oo 

i3 

3,3 1 3 

i3 

3,326 

i3 

3,339 

[2 

3,35i 

i3 

3,364 

12 

3,376 

i3 

3,389 

12 

),0100 

0,11 

3,602 

M 

3,6[6 

i4 

3,63o 

i4 

3,644 

i4 

3,658 

i4 

3,672 

i4 

3,686 

i4 

3,700 

i4 

3,714 

i4 

3,72b 

i3 

1,0121 

0,I2 

3,929 

16 

3,945 

i5 

3,960 

i5 

3.975 

16 

3,991 

i5 

4,006 

[5 

4,021 

i5 

4.036 

i5 

4,o5i 

i5 

4,066 

i5 

0,01 44 

o,i3 

4,256 

17 

4,273 

17 

4,290 

16 

4,3o6 

17 

4.323 

17 

4,34o 

[6 

4,356 

16 

4,372 

17 

4,389 

16 

4,4o5 

16 

0,0169 

o,i4 

4,584 

18 

4,602 

18 

4,620 

17 

4.637 

18 

4,655 

18 

4,673 

18 

4.691 

17 

4,708 

18 

4,726 

17 

4,743 

18 

0,0196 

o,i5 

4,911 

19 

4,930 

'9 

4,949 

19 

4,968 

19 

4,987 

19 

5,006 

■9 

5,025 

'9 

5,044 

19 

5,o63 

19 

5,082 

19 

0,0235 

0,16 

5,237 

2[ 

5,258 

21 

5.279 

20 

5.299 

31 

5,320 

20 

5,34o 

20 

5,36o 

20 

5,38o 

20 

5,400 

20 

5,430 

20 

0,02  56 

0,17 

5,564 

22 

5,586 

22 

5,608 

22 

5,63o 

22 

5,652 

21 

5,673 

22 

5,695 

21 

5,716 

21 

5,737 

22 

5,759 

21 

0,0289 

0,18 

5,891 

23 

5,914 

23 

5,937 

24 

5,961 

22 

5,983 

23 

6,006 

23 

6,029 

23 

6,o53 

22 

6,074 

23 

6,097 

22 

o,o324 

o,ig 

6,218 

24 

6,242 

25 

6,267 

24 

6,291 

24 

6,3i5 

24 

6,339 

25 

6,364 

23 

6,387 

24 

6,4 1 1 

24 

6,435 

24 

o,o36i 

0,20 

6,544 

26 

6,570 

26 

6,596 

26 

6,622 

25 

6,647 

25 

6,672 

26 

6,698 

25 

6,723 

25 

6,748 

25 

6,773 

25 

o,o4oo 

0,21 

6,871 

27 

6,898 

27 

6,925 

27 

6,952 

27 

6,979 

26 

7,oo5 

27 

7,o"32 

27 

7.059 

26 

7,o85 

26 

7,111 

26 

0,044 1 

0,22 

7.197 

29 

7,226 

28 

7.254 

28 

7,282 

28 

7,3io 

28 

7,338 

28 

7,366 

28 

7,394 

28 

7/i22 

27 

7.449 

38 

o,o484 

0,23 

7,524 

29 

7.553 

3o 

7,583 

29 

7,612 

3o 

7,642 

29 

7,671 

29 

7,700 

29 

7,729 

29 

7,758 

29 

7,787 

29 

0,0529 

0,24 

7,85o 

3i 

7,88  [ 

3i 

7.9' 2 

3o 

7.942 

3i 

7,973 

3i 

8,004 

3o 

8,o34 

3o 

8,064 

3i 

8,095 

3o 

8,125 

3o 

0,0576 

0,25 

8,176 

32 

8,208 

32 

8,240 

32 

8,272 

32 

8,3o4 

32 

8,336 

33 

8,368 

3[ 

8,399 

32 

8,43 1 

3i 

8,462 

3i 

0,0625 

0,26 

8,5o2 

33 

8,535 

34 

8,569 

33 

8,602 

33 

8,635 

33 

8,668 

33 

8,701 

33 

8,734 

33 

8,767 

33 

8,800 

32 

0,0676 

0,27 

8,827 

35 

8,862 

35 

8,897 

35 

8,932 

34 

8,966 

35 

Q'™' 

34 

9,o35 

34 

9,069 

M 

9,io3 

34 

9.137 

34 

0,072g 

0,28 

9>i53 

36 

9.189 

36 

9,225 

36 

9.261 

36 

9.297 

36 

9,333 

35 

9,368 

36 

9,404 

35 

9.439 

35 

9.474 

35 

0,0784 

0,29 

9.478 

38 

9,5[6 

37 

9,553 

38 

9.591 

37 

9,628 

37 

9,665 

37 

9,702 

36 

9,738 

37 

9-775 

36 

9,811 

37 

0,084  i 

o,3o 

9,804 

39 

9,843 

38 

9,881 

39 

9.920 

38 

9,958 

39 

9.997 

38 

io,o35 

38 

10,073 

38 

10,1 11 

37 

io,i48 

38 

■1,0900 

o,3i 

10,129 

4o 

10,169 

4o 

10,209 

40 

10,249 

40 

10,289 

39 

10,328 

4o 

io,368 

39 

10,407 

39 

10,446 

39 

10,485 

39 

o,ii(j6i 

0,32 

10,454 

4i 

10,495 

42 

10,537 

4i 

10,578 

4i 

io,6ig 

4i 

10,660 

4o 

1 0,70c, 

4i 

io,74i 

40 

10,781 

41 

10,822 

40 

11,11124 

0,33 

'  0.779 

42 

10,82  [ 

43 

10,864 

43 

10,907 

42 

10,949 

42 

10,991 

42 

ii,o33 

42 

1 1 ,075 

42 

11,117 

41 

ii,i58 

42 

0,1089 

0,34 

ii,io3 

Aà 

ii,i47 

44 

11,191 

Ai 

11,235 

AA 

11,279 

43 

11,333 

44 

11,366 

43 

1 1 ,409 

43 

11,452 

42 

11,494 

43 

0,1 156 

0,35 

[1,428 

45 

11,473 

46 

11,519 

45 

11,564 

45 

1 1 ,609 

Ai 

11,653 

45 

11,698 

44 

11,742 

45 

11,787 

AA 

ii,83i 

AA 

0,1225 

o,36 

11,752 

47 

11.799 

46 

11,845 

47 

1 1 ,892 

46 

11,938 

46 

11,984 

46 

13,o3o 

46 

12,076 

45 

12,121 

46 

12,167 

45 

0,1 296 

0,37 

12,076 

48 

12,124 

48 

12,172 

48 

12,220 

48 

12,268 

47 

i2,3i5 

47 

12,362 

47 

12,409 

47 

12,456 

47 

i3,5o3 

46 

0,1 36g 

o,38 

1 2 ,400 

49 

12,449 

5o 

[2,499 

49 

12,548 

49 

12,597 

48 

12,645 

49 

i2,(ig4 

48 

12,743 

48 

12,790 

48 

12,838 

48 

0,1 444 

0,39 

12,724 

5Ï 

12,775 

5o 

12,825 

5o 

12,875 

5i 

12,926 

5o 

12,976 

49 

1 3,025 

5o 

13,075 

49 

i3,i24 

5o 

i3,i74 

49 

0,1 521 

o,4o 

1 3,047 

52 

13,09g 

52 

[3,[5[ 

52 

i3,2o3 

5i 

i3,354 

52 

i3,3o6 

5i 

i3,357 

5[ 

i3,4o8 

5o 

i3,458 

5i 

i3,5og 

5o 

0,1600 

0,4 1 

i3,370 

54 

1 3,424 

53 

(3,477 

53 

i3.53o 

53 

i3,583 

53 

1 3,636 

52 

1 3,688 

52 

i3,74o 

52 

13,792 

52 

1 3,844 

52 

0,1681 

0,42 

13,693 

55 

1 3,748 

55 

[3,8o3 

54 

1 3,857 

54 

13,91 1 

54 

13,965 

54 

14,019 

54 

14,073 

53 

14,126 

53 

14,179 

53 

0,1764 

0,43 

i4,oiÉ 

56 

14,072 

56 

[4, [28 

56 

14.184 

56 

i4,24o 

55 

14,295 

55 

i4,35c 

55 

i4,4o5 

54 

14,459 

55 

i4,5i4 

54 

0,1 84g 

0,44 

i4,33ç 

57 

[4,396 

58 

14,454 

57 

i4,5ii 

56 

14,567 

57 

[4.624 

56 

1 4,680 

57 

14,737 

55 

14,792 

56 

1 4,848 

56 

0,1936 

0,45 

14.661 

59 

14,72c 

59 

i4,77f 

58 

1 4,837 

58 

14.895 

58 

[4.953 

58 

i5,oii 

57 

1 5,068 

57 

i5,i25 

57 

i5,i82 

57 

0,2025 

o.5o 

[6,26c 

66 

16,335 

65 

16,400 

65 

i6,465 

65 

i6,5'3c 

65 

16,595 

64 

i6,65g 

64 

16,723 

64 

16,787 

63 

1 6,85c 

64 

o,25oo 

0,55 

17.871 

72 

17,942 

73 

i8,oi5 

71 

[8,o8e 

72 

i8,i5E 

71 

[8,23Ç 

72 

i8,3oi 

70 

18,371 

71 

18,442 

70 

i8,5i2 

70 

o,3o25 

0,60 

19,46-. 

80 

19,542 

79 

19,621 

79 

19,70c 

79 

'9.77Ç 

78 

19.85- 

78 

■9.93Î 

77 

20,012 

78 

20,ogc 

77 

20,16- 

76 

o,36oo 

0,65 

2 1  ,o4( 

)   87 

21, i3; 

86 

21,2K 

86 

2[,3o' 

86 

21,39 

85 

2  [,47e 

85 

2i,56[ 

84 

2 1 ,645 

85 

2 1 ,73c 

83 

21,81: 

84 

0,4325 

0,70 

22,62c 

)   94 

22,71^ 

94 

22,8ot 

93 

22,90 

93 

22,99- 

92 

23,o8f: 

92 

23,178 

9- 

23,26c 

92 

23,36i 

90 

23,45i 

91 

0,4900 

0,75 

34,18 

I  lOI 

24,28_ 

lOI 

24,38' 

lOI 

24,48( 

i  100 

24,58f 

)  100 

24,68f 

'   99 

24.78' 

98 

34,88' 

99 

24,98: 

98 

25,o8c 

97 

0,5625 

0,80 

25,73 

1  [09 

25,84; 

109 

25,95 

108 

26,o5( 

)  108 

26,16- 

7  107 

26,27^ 

!  [06 

26,38< 

t  [06 

26,48f 

)  106 

26,59: 

io5 

26,69- 

[o5 

o,64oo 

o,85 

27,27( 

3I[7 

27,38- 

1  116 

27,50, 

i  116 

27,61 

jii5 

27,73, 

iii5 

37,84c 

)  \iA 

27,96 

i  iiA 

28,07- 

7  ii3 

28,19c 

)ii3 

28,30; 

112 

0,7225 

0,90 

28,79 

[25 

28,qi( 

3 124 

29,o4( 

)  12^ 

29, [6 

UM 

29,28 

3  123 

29.4  [< 

1123 

29,53. 

i  [21 

29,65. 

121 

29,77- 

)  120 

29,89' 

120 

0,8100 

0,95 

30,29 

iiM 

3o,42f 

ii33 

3o,56 

l32 

30,69 

3  i32 

30,82 

5i3i 

3o,95( 

1  [3o 

3[,o8( 

3  [3o 

3l,2lf 

3  138 

3 1, 34. 

i  129 

31,47; 

127 

0,9025 

1,00 

3  [,77 

7i43 

3 1,92; 

1  142 

32,06 

7   [4l 

33,20 

3  i4 

32,34 

1i3c 

33,48 

3  i3c) 

32,62 

I  [38 

3  2, 76c 

3i37 

32,89 

7.37 

33,o3^ 

i35 

1 ,0000 

,8065 

,8192 

,8321    1  ,8450 

,8581 

,8712 

1  ,8845 

,8978 

,9113 

1  ,9248 



\  .  (r  -\-  r")'  or   r=  +  r"=    nearly.                                                                                                         | 

322 

323 

324 

325 

326 

327 

328 

329 

33o 

33i 

332 

333 

334 

335 

336 

337 

T 

32 

32 

32 

33 

33 

33 

33 

33 

33 

33 

33 

33 

33 

34 

34 

34 

2 

64 

65 

65 

65 

65 

65 

66 

66 

66 

66 

66 

67 

67 

67 

67 

67 

3 

97 

97 

97 

98 

p8 

98 

98 

99 

99 

99 

100 

100 

100 

101 

101 

101 

A 

i2g 

129 

i3o 

i3o 

i3o 

i3i 

i3i 

I  32 

l32 

l32 

i33 

i33 

1 34 

1 34 

1 34 

i35 

5 

i6[ 

[63 

162 

1 63 

i63 

164 

164 

i65 

i65 

166 

166 

167 

167 

168 

168 

169 

6 

193 

194 

194 

Iq5 

196 

iq6 

197 

197 

ig8 

'99 

199 

200 

200 

201 

202 

202 

■7 

225 

226 

227 

228 

228 

229 

a3o 

23o 

23l 

233 

232 

233 

234 

235 

235 

236 

8 

258 

258 

25g 

260 

261 

262 

262 

263 

264 

365 

266 

266 

267 

268 

269 

270 

S 

290 

291 

292 

293 

293 

294 

295 

296 

=97 

298 

299 

3oo 

3oi 

302 

302 

3o3 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-f-»"",  nnd  the  cliord  c  beinj;  given. 


of   Llio  K^kIii    r+, 


Chonl 
C. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,00 
0,07 
0,0b 
0,09 

0,10 
0,1 1 
0,12 
o,i3 
o,i4 

o,i5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,3  I 
0,2  J 
0,2  J 
0,24 


0,2') 
0,26 
0,37 
0,38 
0,39 

o,3o 
o,3i 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 

0,43 
0,43 
0,44 

o,4'J 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,73 
0,80 
o,85 
0,90 
o,g5 


i,;37 


0,l)UO 

0,340 
o.<i8o 
1 ,03 1 
i,36i 

1,701 
3,04 1 
3,38i 
3,721 
3,(161 

3,4<u 
3,741 
4,081 
4,421 
4.7tJi 

5,101 

5,440 
5,780 

6,1 19 

6,459 

6,798 

7,47- 
7,816 
8,1 

8,493 
8,832 

9 

9.-J09 

9,848 

10,186 
10,524 
10,862 
1 1,300 
11,537 

11,875 
12,212 
12,549 
12,886 

l3,223 

13,559 
13,896 

l4,332 

i4,568 
14,904 

15,239 
16,914 
i8,583 
20,243 
2 1 ,897 
23,543 

25,177 
26,802 
28,4 1 5 
3o,o  1 5 
3i,f5oo 
33,i6g 


18 


43 
45 
46 
48 

49 

5o 

5i 

53 

5. 

55 

5 
63 

70 
76 
83 

9'J 

9' 

io4 
III 
"9 

12-7 

1 351 


1,3d 


Day9  I'Jill 


0,000 
0,341 
o,683 
1,024 

1,366 

1.707 
3,049 

3,3()0 

3,73i 
3,073 

3,4 1 4 
3,7'V", 
4,1 '96 
4,4  i- 

4,778 

5,119 
5,460 
5,801 
6,143 
6,482 

6,823 
7,164 
7,5o4 
7.844 
8,184 

8,525 
8,864 
9,204 
9.544 
9 

10,223 
10,562 

U>,902 

1 1,341 
ii,58o 

1 1,918 
13,357 
I3,5g5 
12,934 
13,273 

13,609 
13,947 
i4,285 
14,622 
14,959 

1 5,396 
16,977 
1 8,652 
20,319 
2 1 ,980 
23,632 

25,274 
26.906 
28,526 
3o,i34 

3l,727 

33,3o4 


1,39 


Days  lilil'. 


0,000 
0,343 
o,685 
1,028 
1,371 

1, 71 3 
2,o56 
2,399 
2,74 1 

3,084 
3,426 

3,-69 

4,1 1 1 
4,453 
4,796 

5,i38 
5,480 

5,833 

6,164 
6,5o6 

6,848 

7.19' 
7.531 
7,873 

8,31 

8,556 
8,897 
9,338 

9.579 
9,930 

10,360 
10,601 
10,941 
1 1,282 
11,622 

1 1,962 

13,3o3 
I  3 ,64 1 
12,981 

1 3,320 

1 3,659 
13,998 
14,337 
14,676 
1 5,01 4 

i5,352 
17,040 
18,721 
20,395 

33,o63 
33,731 

35,370 
27,009 
38,637 

30.2  53 

3 1,853 
33,439 


18 


1,40 


Days  |>hl'. 


9385  I   ,9522 


,9661 


0,000 
0,344 
0,688 

l,o32 

1,376 
1.719 

2,063 
3,407 
2,75i 
3,095 

3,438 
3,783 
4,126 
4,469 
4,81 3 

5,i56 
5,5oo 
5,843 
6,186 
6,529 

6,872 
7.2i5 
7,558 
7,901 
8,244 

8,586 
8,929 

9.271 
9,61 3 
9.956 

10,398 
io,63g 
1 0,98 1 
11,333 
11,664 

I2,005 

1 3,346 
13,687 
13,028 
i3,36g 

13,709 
1 4,049 
14,389 

i4,7'9 
15,069 

i5,4o8 
17,102 
18,790 
20,47 1 
22,145 
23,810 

25,467 
27,11,3 
28,748 
3o,37f) 
3 1,979 


1,41 


U.iya  |dit'. 


33,572(133 


,9800 


0,000 
0,345 
0,690 

i,o35 
1,38 1 

1,736 
2,071 
2,4i6 
2,761 
3,106 

3,45 1 
3,796 
4,i4i 
4,48' 
4,83o 

5,175 
5,5i9 
5,864 
6,208 
6,553 

6,897 
7,241 
7,585 

7.929 
8,373 

8,617 
8,961 
9,3o4 
9,648 
9.991 

10,335 
10,678 

1  I,031 

11,363 
11,706 

12,049 
12,391 
13,733 
13,075 
i3,4i7 

13,759 

l4,!0O 

i4,44i 
14,783 
i5, 123 

1 5,464 
17,164 
18,859 
20,547 
22,227 
23,899 

25,562 

27,3l5 

28,857 
30,487 

33,io4 
33,7o5 


49 
5i 

52 

53 
55 

56 
63 
68 
75 
82 

89 

96 
io3 
no 


I  33 


1,42 


Uiiys  |ilil'. 


0,(J00 

0,346 

0,693 
1 ,0.39 
1,385 

1,732 
2,078 
2,434 
2,771 
3,117 

3,463 
3,809 
4,1 55 
4,5oi 
4,847 

5,ig3 
5,539 
5,885 
6,33o 
6,576 

6,933 
7,367 
7,613 

7.957 
8,3.  " 

8,648 
8,993 
9,338 
9,683 
10,027 

10,371 
10,716 
1 1 ,060 
1 1 ,4o4 
11,748 

12,092 
12,435 

12,779 
1 3,1 22 
1 3,465 

1 3,808 
i4,i5i 
14,493 
1 4,836 
15,178 

1 5,520 
17.227 
18,927 
20,633 

3  2, 309 
23,988 


',3i8 
1,967 
>,6o4 
1,238 
3,837 


25,658   95 

27,"  " 

28, 

3o 

33 

33 


102 
109 
116 

124 

l32 


,9941  I  1,0082 


0,0025 
0,00  36 
o,0(vi9 
o,of.64 
0,0081 

0,0100 
0,01 3  1 
0,0144 
0,01(19 
0,0196 

0,0225 
0,0  2  56 
0,0289 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
o,o484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0739 
0,0784 
0,084 1 

o,ogoo 
0,0961 
0,1024 
0,1089 
0,11 56 

0,1235 
o,  1 396 
0,1 3(19 
o,i444 

0,l531 

0,1600 
0,1681 
o,  1 764 
0,1849 
o,ig36 

0,3035 

0,3  5oo 
o,3o25 
o,36oo 
0,4225 
igoo 

0,5625 
o,64oo 
0,7225 
0,8100 
o,go2  5 
1 ,0000 


(r  -t-   r'f   or   r'+  , 


338 

33g 

340 

341 

342 

343 

344 

345 

346 

347 

I 

34 

34 

34 

34 

34 

34 

34 

35 

35 

35 

3 

68 

68 

68 

68 

68 

69 

69 

69 

69 

69 

J 

lOI 

103 

I03 

102 

io3 

io3 

io3 

io4 

io4 

io4 

4 

i35 

1 36 

1 36 

1 36 

I  37 

1 37 

1 38 

1 38 

1 38 

■39 

5 

.69 

170 

170 

171 

171 

172 

172 

■73 

173 

174 

6 

203 

203 

2o4 

2o5 

205 

206 

206 

207 

208 

208 

7 

237 

237 

a38 

23q 

239 

240 

241 

242 

242 

243 

» 

270 

371 

272 

273 

274 

274 

275 

276 

277 

278 

9 

3o4 

3o5 

3o6 

3o7 

3o8 

3og 

3 10 

3,1 

3ii 

3l2 

l'nj|t.  |iiirt3  fur  lliu  sum  ol'  the  Hailii. 

I  I  2  I  3 1  4 1  5 1  <î  I  7 1  «  I  9 


18    23 
18    23 


24 


28  35 
32  40 
36  45 
4o|5o 


24 

28 

25 
25 

29 
29 

36 

3o 

36 

3i 

27 

32 

38 

32 

38 

33 

29 

34 

29 

34 

3o 

35 

3i 

36 

3i 

3(i 

33 

37 

32 

38 

33 

3q 

34 

3q 

M 

4o 

35 

4i 

35 

4i 

36 

42 

37 

43 

37 

43 

38 

44 

38 

45 

39 

46 

40 

46 

4o 

47 

4i 

48 

4i 

48 

42 

4q 

48 

56 

54 

63 

(>o 

70 

12 
i3 

14 
>4 
i5 
16 
17 
18 

19 
20 
21 
22 

23 
23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 
4o 

4i 
4i 
43 
43 
44 


4o  45 

41 

42 

42 

43 


TABLE 

II. 

—  To  find  the  time  T 

the  sum  of  (he  radii 

r  +  r". 

■  nd  the  chord  e 

being  giren. 

Sum  of  the  Uadii  r-\~T".                                                                                                            1 

Chord 

c. 

1,43 

1,44 

1,45 

1,46 

1,47 

1,48 

Duya  Idif. 

1,49 

1,50 

1,51 

1,52    1 

Us)l  |dir. 

Hay»  jilil'. 

Days  |(lif. 

Uh;s  |dir. 

Days  Idif. 

Days  |dil'. 

Days  Idif. 

Days  lilif. 

Days 

(lit. 

0,00 

0,000 

0,(X)0 

0.000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,348 

I 

0,349 

I 

o,35o 

I 

0,35l 

I 

0,352 

2 

0,354 

I 

0,355 

1 

o,356 

1 

0,357 

1 

0,358 

2 

0,0001 

0,0  a 

0,695 

3 

0,698 

2 

0,700 

2 

0,702 

3 

o,7o5 

2 

0,707 

3 

0,710 

1 

0,712 

2 

0,714 

3 

0,717 

2 

0,0004 

o,o3 

1,043 

3 

1,046 

4 

i,o5o 

4 

i,o54 

3 

i,o57 

4 

1,061 

3 

1 ,064 

4 

1,068 

4 

1,072 

3 

1,075 

4 

0,0009 

o,o4 

1,390 

5 

1,395 

5 

1, 400 

5 

i,4o5 

5 

1,410 

4 

i,4i4 

5 

1,419 

5 

1,424 

5 

1,429 

4 

1,433 

5 

0,0016 

o,o5 

1,738 

6 

1,744 

6 

i,75o 

6 

1,756 

6 

1,762 

6 

1,768 

6 

1,774 

6 

1 ,780 

6 

1,786 

6 

1.792 

6 

0,0025 

0,06 

2,o85 

8 

2,oq3 

7 

2,100 

7 

2,107 

7 

2,114 

7 

2,121 

8 

2,129 

7 

2,i36 

7 

2,143 

7 

2,l5o 

■J 

o,oo36 

0,07 

2,433 

8 

2,441 

9 

2,45o 

8 

2,458 

9 

2,467 

8 

2,475 

8 

2,483 

9 

2,492 

8 

2,5oo 

6 

2,5()6 

8 

0,0049 

0,08 

2,780 

10 

2,790 

10 

2,800 

9 

2,809 

10 

2,819 

10 

2,829 

9 

2,838 

10 

2,848 

9 

2,857 

9 

2,86ti 

10 

0,0064 

0,09 

3,128 

1 1 

3,139 

11 

3,i5o 

10 

3,160 

11 

3,171 

II 

3,182 

11 

3,193 

10 

3,2o3 

3,214 

II 

3,225 

10 

0,0081 

0,10 

3,475 

12 

3,487 

12 

3,499 

12 

3,5ii 

12 

3,523 

12 

3,535 

12 

3,547 

12 

3,559 

12 

3,571 

12 

3.583 

12 

0,0100 

0,1 1 

3,822 

i4 

3,836 

i3 

3,849 

i3 

3,862 

14 

3,876 

i3 

3,88g 

i3 

3.902 

i3 

3,915 

i3 

3,928 

i3 

3,941 

i3 

0,0121 

0,12 

4,170 

i4 

4,1 84 

i5 

4,199 

i4 

4,2i3 

i5 

4,228 

i4 

4,242 

14 

4^256 

i5 

4,271 

i4 

4,285 

14 

4.399 

.4 

0,0144 

0,1 3 

4,5i7 

16 

4,533 

16 

4,549 

i5 

4.564 

16 

4,58o 

i5 

4,595 

16 

4,611 

i5 

4,626 

16 

4,642 

i5 

4.657 

.5 

0,0169 

o,i4 

4,864 

17 

4,881 

17 

4,898 

17 

4,91 5 

17 

4,932 

17 

4,949 

16 

4,965 

17 

4,982 

17 

4,999 

16 

5,oi5 

17 

0,0196 

0,1 5 

5,211 

19 

5,23o 

i& 

5,248 

18 

5,266 

iS 

5,284 

18 

5,3o2 

18 

5,32c 

18 

5,338 

17 

5,355 

18 

5,373 

18 

0,0225 

0,16 

5,558 

20 

5,578 

19 

5,597 

20 

5,617 

19 

5,636 

19 

5,655 

19 

5,674 

19 

5,693 

19 

5,712 

19 

5,73 1 

■9 

0,02 56 

0,17 

5,905 

21 

5,926 

21 

5,947 

20 

5,967 

21 

5,988 

20 

6,ocjS 

20 

6,028 

21 

6,049 

20 

6,069 

20 

6,o8g 

20 

0,0289 

0,18 

6,252 

22 

6,274 

22 

6,296 

22 

6,3i8 

21 

6,339 

22 

6,36 1 

21 

6,382 

22 

6,4o4 

21 

6.425 

23 

6,447 

21 

o,o324 

o,ig 

6,599 

23 

6,622 

23 

6,645 

23 

6,668 

23 

6,691 

23 

6,714 

23 

6,737 

22 

6,759 

23 

6,782 

22 

6,804 

23 

o,o36i 

0,20 

6,946 

24 

6,970 

24 

6,994 

25 

7,019 

24 

7,043 

24 

7,067 

24 

7,091 

23 

7,ii4 

24 

7,1 38 

24 

7,162 

2  3 

o,o4oo 

0,21 

7.393 

25 

7,3i8 

26 

7,344 

25 

7,369 

25 

7,394 

25 

7.419 

26 

7,445 

25 

7,470 

25 

7.495 

34 

7,5 19 

2  5 

o,o44i 

0,22 

7,639 

27 

7,(366 

27 

7,693 

26 

7.719 

2- 

7,746 

26 

7.773 

26 

7,79'^ 

27 

7,825 

26 

7,85i 

26 

7,877 

26 

o,o484 

0,23 

7,986 

2& 

8,oi4 

28 

8,042 

27 

8,069 

28 

8,09- 

28 

8,125 

27 

8,1 5^ 

28 

8,180 

37 

8,207 

27 

8,334 

37 

0,0529 

0,24 

8,332 

39 

8,36i 

=9 

8,390 

=9 

8,419 

29 

8,448 

29 

8,477 

29 

8,5ot 

29 

8,535 

28 

8,563 

28 

8,591 

29 

0,0576 

0,35 

8,678 

3i 

8,709 

3o 

8,739 

3o 

8.769 

3i 

8,800 

3o 

8,83o 

29 

8,859 

3o 

8,889 

3o 

8,919 

3o 

8,949 

29 

0,0625 

0,26 

9.025 

3i 

9,o56 

32 

9,088 

3i 

9,119 

35 

9,i5i 

3i 

9,182 

3i 

9.213 

3i 

9,344 

3i 

9.275 

3i 

9,3o6 

3" 

0,0676 

0,27 

9,371 

33 

9,404 

32 

9,436 

33 

9,469 

33 

g,5o2 

32 

9,534 

32 

9^566 

33 

9,599 

32 

9,63 1 

33 

9,663 

32 

0,0729 

0,2« 

9.717 

34 

9,75i 

34 

9,785 

34 

9,819 

33 

9,852 

34 

9,886 

34 

9.920 

33 

9,953 

33 

9,986 

34 

10,020 

33 

0,0784 

0,29 

10,062 

36 

10,098 

35 

io,i33 

35 

10,168 

35 

I0,203 

35 

10,238 

35 

10,273 

34 

10,307 

35 

10,342 

34 

10,376 

35 

0,084 I 

o,3o 

io,4o8 

37 

10,445 

36 

10,481 

37 

io,5i8 

36 

10,554 

36 

10,590 

36 

10,626 

36 

10,662 

35 

10.697 

36 

10,733 

35 

0,0900 

0,3 1 

10,754 

36 

10,792 

37 

10,829 

38 

10,867 

3? 

10,904 

38 

10,942 

37 

10,979 

37 

1 1,016 

37 

ii;o53 

37 

1 1 ,090 

36 

o,fj96i 

0,32 

1 1 ,099 

3q 

ii,i38 

3g 

11,177 

39 

1 1,216 

39 

11,255 

38 

11,293 

3g 

11,335 

38 

1 1 ,370 

38 

1 1 ,408 

38 

1 1 ,4^16 

3fc 

0,1024 

0,33 

11.444 

4i 

1 1 ,485 

4a 

11,525 

4o 

11,565 

40 

ii,6o5 

40 

11,645 

39 

1 1 ,684 

4o 

11,724 

39 

11,763 

3q 

1 1 ,802 

39 

0,1089 

0,34 

11,790 

4i 

ii,83i 

42 

11,873 

4i 

11,914 

4i 

11,955 

4i 

1 1 ,996 

4i 

i2,o37 

40 

12,077 

4i 

12,118 

4o 

I2,i58 

4i 

0,1 1 56 

0,35 

i2,i35 

42 

12,177 

43 

12,220 

43 

12,263 

42 

i2,3o5 

42 

12,347 

42 

1 2 ,389 

42 

i2,43i 

43 

12,473 

4i 

i2,5i4 

42 

0,.225 

o,36 

12,479 

44 

12,523 

44 

12,567 

44 

12,61 1 

44 

12,655 

43 

12,698 

43 

12,74"l 

43 

12,784 

43 

12,827 

43 

1 2 ,870 

43 

0,1296 

0,37 

12,824 

45 

12,869 

46 

12,915 

44 

12,959 

45 

1 3,004 

4'. 

1 3,049 

44 

13,093 

45 

i3,i38 

44 

I3.I82 

44 

l3,226 

44 

0,1369 

0,38 

13,169 

46 

i3,2i5 

47 

13,262 

46 

i3,3o8 

46 

i3,354 

4fc 

i3,4oo 

45 

1 3,445 

46 

13,491 

45 

13.536 

45 

i3,58i 

46 

0,1 444 

0,39 

i3,5i3 

48 

i3,56i 

47 

1 3,608 

48 

1 3,656 

47 

i3,7o3 

4- 

i3,75o 

47 

.3,79- 

47 

1 3,844 

46 

13,890 

47 

13,937 

46 

0,l52I 

o,4o 

1 3,857 

49 

13,906 

49 

13,955 

49 

i4,oo4 

48 

i4,o52 

49 

i4,ioi 

48 

i4,i49 

48 

14,197 

48 

14,245 

47 

14,293 

48 

0,1600 

0,4 1 

l4,20I 

5i 

l4,252 

5o 

14,3C2 

49 

i4,35i 

5c. 

i4,4oi 

5o 

i4,45i 

49 

i4,5oc 

49 

14,549 

49 

14,598 

49 

14,647 

49 

0,1681 

0,42 

r4,545 

52 

14,597 

5i 

14,648 

5i 

14,699 

5i 

i4,75o 

5i 

i4-8oi 

5o 

i4,85i 

5i 

14,902 

5o 

14,952 

5c 

1 5.003 

5o 

0,1764 

0,43 

14,889 

52 

14.941 

53 

14,994 

52 

1 5,046 

53 

i5,oqQ 

52 

i5,i5i 

52 

i5.2o3 

5i 

15.254 

53 

i5,3o6 

5i 

1 5,357 

5i 

0,1849 

0,44 

I  5,232 

54 

15,286 

54 

1 5,340 

54 

15,394 

53 

1 5,447 

53 

i5,5ou 

53 

1 5,553 

53 

1 5,606 

53 

1 5,659 

53 

i5,7i2 

53 

0,1936 

0,45 

15,575 

56 

1-5,63 1 

55 

1 5,686 

55 

1 5,741 

54 

1 5,795 

55 

i5,85o 

54 

15.904 

54 

15.958 

54 

16,012 

54 

16,066 

54 

0,2025 

0,5., 

17,288 

62 

i7,35o 

61 

17,411 

62 

17,473 

61 

17,534 

60 

17.594 

61 

17,655 

60 

17,715 

60 

17.775 

60 

17,835 

60 

0,25oO 

0,55 

18,996 

68 

ig,o64 

67 

19,1 3 1 

68 

19,199 

67 

19,266 

67 

19,333 

67 

1 9,400 

67 

19,467 

66 

19,533 

66 

19,590 

66 

o,3o25 

0,60 

20,696 

75 

20,771 

74 

20,845 

74 

20,919 

74 

20,993 

73 

2 1 ,066 

73 

21,139 

73 

21,213 

73 

2  1,285 

72 

21,357 

73 

o,36ûo 

0,65 

2  2,3go 

81 

22,471 

81 

22,552 

81 

22,632 

81 

22,7l3 

7^) 

22.792 

8c 

22,872 

79 

22,951 

79 

23,0 3o 

79 

23,icq 

78 

0,4225 

0,70 

24,076 

87 

24,i63 

88 

24,25l 

87 

24338 

87 

24,425 

8t 

24,5ii 

86 

24,597 

86 

24,683 

85 

24,768 

85 

24,853 

85 

0,4900 

0,75 

25,753 

94 

25,847 

94 

25,941 

94 

26,035 

93 

26,128 

9" 

26,221 

93 

26,3i4 

92 

26,406 

92 

26,498 

92 

26.590 

9' 

o,5635 

0,80 

27,42f 

101 

27,521 

loi 

27,622 

101 

27,723 

100 

27,823 

lOC 

27,923 

99 

28,022 

99 

28,121 

99 

28,220 

98 

28,3.8 

98 

0,6400 

o,85 

29,076 

106 

29,184 

loç 

29,293 

107 

29,400 

107 

29,507 

10- 

29.61.; 

10É 

39,720 

lot 

29,826 

106 

29.932 

.05 

3o,o37 

io4 

0,7335 

0,90 

3o,72c 

lit 

3o,83b 

lit 

3o,q52 

ii4 

3 1,066 

ii5 

3i,i8i 

IK 

3 1^294 

114 

3 1,408 

112 

3i,52c 

ii3 

31.633 

1 12 

3 1,745 

1 1 1 

0,8100 

0,95 

32,352 

12C 

32,475 

12C 

32,598 

122 

32,72( 

121 

32,841 

12 

32.962 

121 

3  3. 08  3 

12c 

33,2o3 

119 

33,322 

"9 

33.44. 

no 

0.9035 

1,00 

33,96c 

.3 

34,10c 

i3c 

34,23o 

i3ol34,36o 

12c 

34,489 

12f 

34,617 

126 

34,745 

128 

34,873 

136 

34,999 

136 

35,1251.36 

1 ,0000 

1,0225 

1 ,0368 

1,0513  1  1,0658 

1 ,0805 

1 ,0952 

1,1101  1  1,1250 

1,1401 

1,1552 

(2 

i  ■ 

(r  +  r-f 

or    j'^  -j-  r"'^  nearly.                                                                                                     | 

343 

344 

345 

346 

347 

348 

349 

35o 

35. 

352 

353 

354 

355 

356 

357 

358 

35y 

I 

34 

U 

35 

35 

35 

35 

35 

35 

35 

35 

35 

35 

36 

36 

36 

36 

36 

2 

6q 

69 

69 

69 

69 

70 

70 

70 

70 

70 

71 

71 

71 

7' 

71 

72 

73 

3 

io3 

io3 

1 04 

104 

io4 

104 

io5 

io5 

io5 

106 

106 

106 

107 

107 

107 

107 

108 

4 

.37 

i38 

i38 

i38 

i3q 

.3q 

i4o 

i4o 

i4o 

i4i 

i4. 

142 

l42 

142 

143 

143 

144 

5 

173 

172 

173 

173 

174 

174 

175 

175 

176 

176 

177 

177 

178 

178 

179 

179 

180 

6 

206 

206 

207 

208 

208 

309 

309 

310 

211 

211 

2.2 

212 

3l3 

ai4 

214 

2.5 

2l5 

7 

340 

241 

245 

242 

--4J 

■i44 

■i44 

245 

246 

246 

247 

248 

249 

249 

2  5o 

35l 

35l 

8 

274 

275 

276 

277 

278 

278 

279 

280 

281 

281 

282 

283 

284 

285 

386 

286 

387 

9 

309 

3io 

3ii 

3ii 

3l2 

3i3 

3i4 

3i5 

3i6 

3l7 

3.8 

319 

320 

320 

321 

323 

323 

TABLE  II.  —  To  find  the  time  T\  the  sum  of  the  radii  r-j-  r",  and  the  chord  c  being  given. 


Suit!  ol'  the  Riulu  r-|-7-'. 


CliorJ 

c. 

0,00 
0,01 
0,1)  a 
o,o3 
o,u4 

o,()5 
0,06 
0,07 
o,oS 
o,og 

0,10 
0,1  i 
0,1  3 
0,1 3 
0,1 4 

0,1 5 
0,16 
0,17 
0,18 
0,19 

0,20 

0,2  1 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 


0,75 
0,80 
o,85 
o,go 
0,91 
1,00 


1,53 


l)u>«  l.lit. 


0,00(1 
o,36o 
0,719 
1,079 
1,438 

1,798 

2,ID7 
2,5l() 

2,876 

3,235 

3.595 
3.g'j4 
4.3i3 
4,673 
5,o32 

5,391 
5,75u 
6, 1 09 
(i,466 
6,83 

7,i8 

7.544 

7,903 

8,361 

8,620 

8,978 
9,336 

io,o53 
io,4i  I 

10,768 
1 1,126 
11,484 
ii,84i 
12,199 

12,556 
12,913 
13,370 
13,627 
13,983 

!  4,340 
14,696 

i5,o53 

1 5,408 
15,764 

16,120 

17,895 
19,665 

21,439 

23,187 
34,938 

36,681 
28,416 

3o,i4i 
3 1, 856 


19 


1,54 


Days  |ilif. 


33,56c)  118 
35,25i|i35 


0,000 
o,36i 

0,73  1 
1 ,082 
1,443 

1 ,8o3 
2,164 

2,52 

2,885 
3,246 

3,606 
3,y6- 
4,J3- 
4.688 
5,048 

5,408 
5.769 
6,129 
6,489 
6,849 

7,309 
7,569 

7.929 
8.388 
8,648 

9,008 
9,367 
9,736 
10,086 
10,445 

io,8o4 
1 1 , 1 63 
11,522 
11,1 
12,239 

12,597 
I2.g55 
i3,3i4 
1 3,671 
14,029 

14,387 
14,745 

l5.I03 

15,459 

i5,8i6 

16,173 
17.954 
19,731 

2I,50I 

23,365 
35,023 

36.773 
28,5i3 
30.345 
31,96- 
33,678 
35,376 


1,1705 


23 

34 

25 

27 
38 

il 

32 

33 
34 

35 
36 

3 

39 
40 

4i 
43 
43 
45 
46 

47 
48 

49 

5i 

52 

53 
60 
6: 
72 
78 


0,000 
o,363 
0,724 
1 ,086 
1,44 

1,809 

2,171 

2,533 
2,895 
3,256 

3,618 
3,980 
4,341 
4,703 
5,064 

5,436 
5,787 
6,149 
6.5io 
6,871 

7.233 

7,593 

7.954 

8,3i5 
8,676 

9,o37 

9,398 

9,758 
10,1 19 
10,479 

10,839 

11,199 
ii,55q 

'i.9'9 
12,279 

12,638 
12,998 
1 3,357 
i3,7i6 
14,075 

14,434 
14.793 
i5,i5i 
i5,5io 
1 5,868    53 


1,1858 


16,226 
i8,oi4 
19,796 
21,573 
33,343 
35,107 

36,863 
38;6io 
3o,349 
32.078 
33,795 
35,5oi 


1,56 


Days  |<lir. 


0,000 

o,3(vi 
0,726 
1 ,089 
1,452 

1,81 5 
2,178 
2,541 

3 ,904 
3,267 

3,63( 

3,993 

4,355 

4.718 

5,o8i 

5,443 
5,806 
6,169 
6,53 1 
6,893 

7,2  50 
7,618 
7,980 
8,342 
8,704 

g,o66 
9,428 

9.790 
io,i5i 
io,5i3 


10,874 
11,23 
1 1 .597 
ii,g58 
I2,3ig  3y 


12,679 
i3,o4o 
i3,4oi 
13,761 

l4,I2I 

14.48 1 

i4,84i 
1 5,201 
i5,56o 
15,920 

16,27g 

18,073 

19,861 

21,644 

33,43 

35,191 


90  26,953 

97  38,707 

"  3o,452 

32,1 

33,gi3 
35,635 


124 


1,2013 


1,57 

Uiiys  IJlf. 


0,000 

o,364 
0,738 
1 ,093 


1,831 
3,i85 
2,549 
2,913 
3.-^77 

3,64 1 
4,oo5 
4.369 
4.733 
5,097 

5,461 
5,835 
6,188 
6,552 
6,916 

7.'79 
7,643 
8,006 
8,369 
8,732 

9.095 
9,458 
9,821 
10,184 
10,547 

10,909 
11.273 
11,634 
1 1 ,996 
12,358 


12,720 
1 3,083 
1 3,444 
i3,8o5 
46  14,167 


1,2168 


14,538 
i4.i  . 
i5,25o 
1 5,611 
15,971 

16,332 
i8,i3i 
19,926 
2 1 ,7 1 5 
23,4g8 
25,274 

27,043 
38,804 
3o,555 
32,297 
34,039 
35,748 


18 

3(J 
31 
22 

23 

35 

35 

3 

28 

29 

3o 

33 

33 
33 

35 
36 
3' 

39 
4o 

4i 
43 
43 

45 
45 

4- 
48 

49 
5o 

53 

53 

59 
65 

71 
77 
83 

90 
9O 
io3 
110 
116 

123 


1,58 


Daya  Idif. 


1 ,2325 


0,00c 

o,365 
0,73 1 
I  ,og6 
1,461 

1,827 
2,193 
2,557 
3,923 
3,288 

3,653 
4,018 
4.383 
4,748 
5,ii3 

5,47 

5,843 

6,208 

6,573 

6,938 

7,3o2 
7.66- 
8,o3i 
8,396 
8,760 

9,124 
9,488 
9,85- 
10,317 
io,58o 

io,g44 
ii,3o8 
1 1 ,67 1 
i3,o35 
12,398 

13,761 
13,124 
i3,48 
i3,85o 

l4,213 

14,575 

i4,g37 
i5,3gg 
1 5,661 
16,033 

i6,385 
18,190 

19,991 
31,786 

33,575 

35,357 

27,i33 
38,900 
3o,658 
33,4o' 
34,145 
35,871 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0035 

,oo36 

0,0049 

0,0064 
Hi 

ft, 01 00 
0,01  2  1 

0,01 44 
0,01 6g 
0,0196 

e),0225 

0,0  2  56 
0,038g 
o,o334 
o,o3ôi 

o,o4oo 
0,044 1 
0,0484 
o,o53g 
0,0576 

0,0625 
0,0676 
0,072g 
0,0784 
0,084 1 

o,ogoo 
o,og6i 
0,1024 
0,1  o8g 
0,1 156 

0,1225 
0,1 2g6 
0,1 36g 
0,1 444 
0,1 521 

0,1600 
0,1681 
0,1764 
0,1 84g 
0,1936 

0,3025 
o,25oo 

0,3o25 

o,36oo 
0,4235 
0,4900 

0,5625 
0,64*00 
0,7335 
0,8100 
0,9025 
10,000 


1,2482 


(  r  -(-  r  "  )^  or  r'  -f-  r  '  '  neatly. 


I'l'ip.  (titrtnlur  the  sum  of  ihe  Kiidii. 

1  I  3  I  3  1  4  I  5  1  6  I  7  I  8  I  9 


356 

357 

358 

36 

36 

36 

71 

71 

72 

107 

107 

107 

142 

143 

i43 

178 

'79 

179 

2l4 

2l4 

2l5 

249 

25o 

231 

285 

286 

286 

320 

331 

332 

359 

36 

72 

108 

1 44 

:8o 

2l5 
25l 

287 

323 


36o 

36 
73 
108 
144 
180 
216 
252 
388 
334 


36 1 


36 
72 
108 
1 44 
181 
217 
253 
289 
335 


362 


36 
72 
109 
145 
181 
217 
253 
290 
326 


363 


36 
73 
log 
i45 
182 
218 
254 
290 
327 


364 

365 

366 

36 

37 

37 

73 

73 

73 

109 

no 

no 

1 46 

146 

i46 

183 

i83 

i83 

218 

219 

220 

255 

256 

256 

291 

392 

293 

338 

32g 

339 

i3 

i4 

i5 
16 

17 
18 

19 

20 
21 
22 

23 

24 

25 

26 

27 
28 
29 

3o 
3i 

33 

33 
34 

35 
36 

37 
38 

39 

40 
4i 
42 
43 
AA 

45 
46 
47 
48 

49 

5o 
5i 

52 

53 

54 

55 
56 

57 
58 

59 

60 
61 
62 
63 

64 

65 
66 

67 
68 

69 

70 

80 

90 

100 


1 1 

1 1  16 

17 
17 
17 

12  17 
12  18 


i5  30 
i5|  20 
16 
16 


23 

24 

25 

26 
26 
27 

28 

29 
3o 
3o 
3i 

32 

33 
34 
34 
35 

36 

37 
38 
38 
3g 

4o 
4i 
42 
42 
43 

AA 
45 
46 
46 

47 

48 

49 

5^ 


23 
23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 
39 
40 

4r 
4i 
42 
43 
AA 

45 
46 
47 
48 

49 

5o 
5o 
5i 

52 

53 

54 
55 
56 

57 
58 

59 

59 
60 
6i 
62 

63 
72 
81 
90 


TAPLE 

11. 

—  Tofi 

11(1  the  time 

T; 

the  sum  0 

f  tlie  ra 

ciii  > 

4-  r",  and 

the  chc 

rd  c 

being  given. 

Sum  ut"  llie  Radii  r-\-r  '.                                                                                                                        | 

Chord 
C. 

1,59 

1,60 

1,61 

1,62 

1,63 

1,64 

1,65 

Days  Iclir. 

1,66 

Days  [dit'. 

1,67 

1,68 

Days  |dir. 

bays  |ilil'. 

Uays  |dlt'. 

Days  lilil'. 

Days  |.lir. 

Duy.-î  |.]ir. 

Days  |4ir. 

Day.s  |dir. 

0,00 

0,000 

0,000 

0,000 

0,000 

o,00ù 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,367 

I 

0,368 

I 

0,369 

1 

0,370 

1 

0,371 

I 

0,372 

1 

0,373 

3 

0,375 

1 

0,376 

1 

0,377 

1 

0,0001 

0,02 

0,733 

2 

0,735 

3 

o,738 

3 

0,740 

2 

0,742 

2 

0,744 

3 

0,747 

2 

0,749 

2 

o,75i 

2 

0,753 

3 

0,0004 

o,o3 

1,100 

3 

i,io3 

3 

1,106 

4 

1,110 

3 

i,ii3 

4 

1,117 

3 

1,120 

3 

1,123 

4 

1,127 

3 

1 , 1 3o 

4 

0,0009 

0,04 

1,466 

5 

^At 

4 

1,475 

5 

1, 480 

4 

1,484 

5 

1,489 

4 

1,493 

5 

1,498 

4 

I,5o2 

5 

i,5o7 

4 

0,0016 

o,o5 

1,832 

6 

1,838 

6 

1,844 

6 

1 ,85o 

5 

1,855 

6 

1,861 

6 

1,867 

5 

1,873 

6 

1,878 

6 

1,884 

5 

0,0025 

0,06 

2,199 

7 

2,206 

7 

2,213 

7 

2,220 

6 

2,226 

7 

2,233 

7 

3,240 

7 

2,247 

7 

2,254 

6 

2,260 

7 

o,oo36 

0,07 

2,565 

8 

2,573 

8 

2,58i 

8 

2,589 

8 

2,597 

8 

2,6o5 

8 

2,6i3 

8 

2,621 

8 

2.629 

8 

3,637 

J. 

0,0049 

0,08 

2.932 

9 

2.941 

9 

2.950 

9 

2,959 

9 

2.968 

10 

2,978 

9 

2,987 

9 

2-996 

9 

3,oo5 

9 

3,014 

9 

0,0064 

0,09 

3,298 

11 

3,309 

10 

3,319 

xo 

3,329 

10 

3;339 

II 

3,35o 

10 

3,36o 

10 

3,370 

10 

3,38o 

10 

3,390 

10 

0,008 1 

0,10 

3,665 

11 

3,676 

12 

3,688 

1 1 

3,699 

11 

3,710 

12 

3,732 

II 

3,733 

1! 

3,744 

12 

3,756 

11 

3,767 

1 1 

0,0100 

0,11 

4,o3i 

12 

4,043 

i3 

4,o56 

x3 

4,069 

12 

4,081 

i3 

4,094 

12 

4,106 

i3 

4,119 

12 

4,i3i 

12 

4,143 

i3 

0,01 21 

0,12 

4,397 

i4 

4,411 

i4 

4,425 

i3 

4,438 

i4 

4.452 

i4 

4.466 

i3 

4,479 

i4 

4,493 

13 

4,5o6 

i4 

4,520 

i3 

0,01 44 

0,1 3 

4,763 

i5 

4,778 

i5 

4,793 

i5 

4,808 

i5 

4,823 

i5 

4,838 

14 

4,852 

i5 

4,867 

i5 

4,882 

i4 

4,896 

i5 

0,0169 

o,i4 

5,129 

17 

5, 1 46 

16 

5,162 

16 

5,178 

16 

5,194 

16 

5,210 

16 

5,226 

i5 

5,241 

16 

5,257 

16 

5,273 

16 

0,01 96 

o,i5 

5,496 

17 

5.5i3 

17 

5,53o 

17 

5,547 

17 

5,564 

17 

5.58 1 

17 

5,598 

17 

5,6i5 

17 

5,632 

17 

5,649 

17 

0,0225 

0,16 

5,862 

18 

5,880 

19 

5,899 

18 

5,917 

18 

5,935 

18 

5;953 

18 

5,971 

19 

5,990 

18 

6,008 

18 

6,026 

ifc 

0,02  56 

0,17 

6.228 

'9 

6,247 

20 

6,267 

■9 

6,286 

20 

6,3o6 

19 

6,335 

19 

6,344 

20 

6.364 

19 

6.383 

19 

6,402 

■9 

0,0389 

0,18 

6,594 

20 

6,614 

21 

,  6,635 

31 

6,656 

20 

6,676 

21 

6,697 

20 

6,717 

21 

6;738 

20 

6,758 

20 

6,778 

2C 

o,o334 

0,19 

6,960 

21 

6,981 

22 

7,oo3 

22 

7.025 

22 

7.047 

21 

7,068 

32 

7,090 

21 

7,111 

23 

7,.33 

21 

7,1 54 

22 

o,o36i 

0,20 

7,325 

23 

7,348 

23 

7,37. 

23 

7,394 

33 

7.417 

33 

7,440 

23 

7.463 

22 

7,485 

23 

7.508 

22 

7,53o 

23 

o,o4oo 

0,21 

7.691 

24 

7,7  >  5 

24 

7.739 

25 

7,764 

24 

7,788 

23 

7,811 

24 

7,835 

34 

7,859 

24 

7,883 

23 

7.906 

24 

0,044 1 

0,22 

8,057 

25 

8,082 

2  5 

8,107 

26 

8,i33 

25 

8,1 58 

25 

8,i83 

25 

8,208 

35 

8,233 

3  5 

8,258 

24 

8.283 

25 

0,0484 

0,23 

8.422 

27 

8,449 

36 

8,475 

27 

8,5o2 

26 

8,528 

26 

8,554 

36 

8,58o 

26 

8,606 

26 

8,632 

26 

8,658 

26 

0,0529 

0,24 

8,788 

28 

8,816 

27 

8,843 

28 

8,871 

27 

8,898 

27 

8,925 

28 

8,953 

27 

8,980 

27 

9.007 

27 

9,o34 

27 

0,0576 

0,25 

9.153 

29 

9,182 

29 

9,2 1 1 

29 

9.240 

28 

9,268 

29 

9.297 

28 

9,32  5 

28 

9,353 

29 

9,382 

38 

9.410 

28 

0,0625 

0,26 

9^519 

3o 

9-549 

3u 

9.579 

29 

9,608 

3o 

9,638 

3o 

9,668 

29 

9.697 

3o 

9-727 

29 

9,756 

29 

9.785 

3o 

0,0676 

0,27 

9,884 

3i 

9-9 '5 

3i 

9,946 

3i 

9-977 

3i 

10,008 

3i 

io,o3g 

3o 

10,069 

3i 

io,ioo 

3i 

io,i3i 

3o 

10,161 

3o 

0,0739 

0,28 

10,249 

32 

10,281 

33 

10,3  [4 

33 

10,346 

32 

10,378 

32 

io,4io 

33 

10,442 

3i 

10,473 

32 

io,5o5 

3i 

10,536 

33 

0,0784 

0,29 

io,6i4 

34 

10,648 

33 

10,681 

33 

10,714 

33 

10,747 

33 

1 0,780 

33 

10,8 1 3 

33 

10,846 

33 

10,879 

33 

10.912 

32 

0,084 1 

o,3o 

10,979 

35 

ii,oi4 

34 

1 1 ,048 

35 

1 1 ,08  3 

34 

11,1 17 

34 

ii,i5i 

34 

ii,i85 

34 

11,219 

34 

11,253 

34 

1 1,387 

34 

0,0900 

0,3 1 

11,344 

36 

ii,38o 

35 

ii,4i5 

36 

11.451 

35 

11,486 

36 

11,522 

35 

11,557 

35 

11,592 

35 

11,627 

35 

1 1 ,662 

35 

0,0961 

0,32 

1 1 ,708 

37 

11,745 

37 

11,782 

37 

1 1 ,8 1 9 

37 

11,856 

36 

11,892 

37 

1 1 ,929 

36 

11,965 

36 

12.001 

36 

i2,o37 

36 

0,1034 

0,33 

12,073 

38 

12,1 1 1 

38 

12,i4q 

38 

12.187 

38 

12,225 

38 

12,263 

37 

i2,3oo 

38 

12,338 

37 

I2;375 

37 

12,412 

3- 

0,1089 

0,34 

12,437 

4o 

12,477 

39 

X2,5i6 

39 

12,555 

39 

12,594 

39 

12,633 

39 

12,672 

38 

12,710 

39 

12,749 

38 

12,787 

38 

0,11 56 

0,35 

12,802 

4o 

12.842 

4i 

12,883 

4o 

[2,923 

4o 

12,963 

40 

i3,oo3 

4o 

1 3,043 

40 

i3,o83 

39 

l3,122 

40 

i3,i62 

39 

0,1225 

o,36 

i3,i66 

42 

1 3.208 

4i 

13,249 

42 

13,291 

4i 

i3,332 

4i 

13,373 

41 

i3,4i4 

4i 

i3,455 

4i 

13,496 

4o 

i3,536 

4i 

0,1296 

0,37 

i3,53o 

43 

13.573 

43 

i3,6i6 

42 

1 3,658 

43 

i3,70i 

42 

13.743 

42 

15.785 

42 

13,827 

42 

13.869 

42 

13,91 1 

43 

0,1369 

o,38 

13.894 

M 

1 3,938 

44 

13,982 

44 

14.026 

43 

14,069 

44 

i4,ii3 

43 

i4,i56 

43 

14.199 

43 

14,242 

43 

i4,285 

43 

0,1444 

0,39 

i4,258 

45 

i4,3o3 

45 

14,348 

45 

14.393 

45 

i4,438 

44 

14,482 

45 

14,527 

44 

14,571 

44 

i4,6i5 

45 

1 4,660 

44 

0,1 52  I 

o,4o 

14.621 

47 

1 4,668 

46 

14.714 

46 

14,760 

46 

i4,8o6 

46 

i4,852 

46 

14,898 

45 

14,943 

45 

14.988 

46 

1 5.0  34 

45 

0,1600 

0,4 1 

14.985 

47 

i5.o33 

46 

1 5,080 

47 

l5,127 

47 

i5,i74 

47 

l5,221 

47 

1 5,368 

47 

i5,3i5 

46 

i5,36i 

47 

1 5.408 

46 

0,1681 

0,42 

1 5.34s 

49 

15,397 

48 

1 5,445 

49 

15,494 

48 

1 5,542 

48 

15,590 

48 

15.638 

48 

1 5,686 

48 

15,734 

47 

15,781 

48 

0,1764 

0,43 

15.711 

5o 

15,761 

5o 

1 5,8 11 

5o 

1 5,861 

49 

15,910 

49 

15,959 

5o 

16,009 

49 

i6,o58 

48 

16,106 

49 

i6,i55 

49 

0,1849 

0,44 

16,074 

5i 

16,125 

5i 

16,176 

5i 

16,227 

5i 

16,278 

5o 

16,328 

5i 

16,379 

DO 

16,429 

5o 

16,479 

5o 

16,529 

49 

0,1936 

0,45 

16,437 

52 

16,489 

53 

16,542 

52 

16,594 

5i 

16,645 

52 

16,697 

5i 

16,748 

52 

16,800 

5i 

i6,85i 

5i 

16.902 

5] 

0,2025 

o,5o 

18,249 

58 

i8,3o7 

58 

18, 365 

58 

18,423 

58 

18,481 

57 

i8,538 

57 

18.595 

58 

1 8,653 

57 

18,710 

56 

18,766 

57 

o,2  5oo 

0,55 

20.o5"5 

65 

20,120 

64 

20,184 

63 

20,247 

64 

20,3ll 

64 

20,375 

63 

30,438 

63 

2o.5oi 

63 

20,564 

63 

20,626 

63 

o,3o25 

0,60 

21,856 

71 

21,937 

7C 

21.997 

70 

22.067 

69 

22,l36 

70 

22,206 

69 

22,275 

69 

22,344 

69 

22,4l3 

68 

22,481 

69 

o,36oo 

o,65 

23,652 

76 

23.728 

76 

23,8o4 

76 

23,880 

76 

2  3,956 

76 

24,o32 

75 

24,107 

75 

24,182 

74 

24,256 

75 

24,33 1 

74 

0,4225 

0,70 

25,44o 

83 

25^523 

82 

25,6o5 

83 

25,688 

81 

25,769 

82 

25,85i 

81 

25,932 

81 

36,oi3 

81 

26,094 

80 

26,174 

81 

0,4900 

0,75 

27,222 

89 

27,3ii 

86 

27,399 

89 

27,488 

88 

27,576 

88 

27,664 

87 

27,751 

87 

27,838 

87 

37,925 

86 

28,011 

87 

o,5625 

0,80 

28,995 

gt 

29,091 

95 

29,186 

94 

29,280 

95 

29.375 

94 

39,469 

93 

39,562 

94 

29,656 

93 

29.749 

92 

39,841 

93 

o,64oo 

o,85 

30,760 

103 

30.862 

101 

30.963 

101 

3 1,064 

101 

3i,i65 

100 

3 1,265 

100 

3 1, 365 

100 

3 1, 465 

99 

3 1,564 

99 

3 1, 663 

99 

0,7225 

0,90 

32,5i5 

109 

32,624 

108 

32,732 

107 

33,839 

108 

32,947 

106 

33,o53 

107 

33.160 

106 

33,266 

io5 

33,371 

106 

33,477 

io5 

0,8100 

o,g5 

34.260 

1x5 

34,375 

1x5 

34,490 

114 

34.604 

114 

34,718 

114 

34,833 

112 

34,944 

ii3 

35,o57 

112 

35,169 

113 

35,281 

III 

0,9025 

1 ,00 

35,994 

122 

36,1 16 

121 

36,2  37 

121 

36,358 

121 

36,479 

120 

36,599 

120 

36.719 

119 

36,838 

'■9 

36,957 

118 

37,075 

118 

1 ,0000 

1,2641  1  1,2800 

1,2961 

1,3122 

1,3285 

1,3448 

1,3613 1 

1,3778  1 

1 ,3945  1 

1,41 12  1 

«2 

i  .  (r  +  r")-  or   7-'^  4-  r  "  ^    nearly.                                                                                                        | 

I 
I 


363 

364 

365 

366 

367 

368 

369 

370 

371 

372 

373 

374 

375 

376 

377 

36 

36 

37 

37 

37 

37 

37 

37 

37 

37 

37 

37 

38 

38 

38 

73 

73 

73 

73 

73 

74 

74 

74 

74 

74 

75 

75 

75 

75 

75 

109 

109 

no 

no 

1 10 

no 

1 11 

in 

III 

112 

112 

112 

ii3 

ii3 

n3 

145 

1 46 

1 46 

146 

1 47 

1 47 

1 48 

1 48 

1 48 

1 49 

149 

i5o 

i5o 

i5o 

i5i 

182 

182 

i83 

1 83 

1 84 

184 

i85 

i85 

186 

186 

187 

1S7 

188 

188 

189 

218 

218 

219 

220 

230 

321 

231 

222 

223 

223 

224 

224 

225 

226 

226 

254 

255 

2  56 

256 

257 

2.58 

258 

259 

260 

260 

261 

262 

263 

263 

264 

200 

291 

392 

2q3 

294 

294 

2q5 

396 

297 

298 

298 

?99 

3oo 

3oi 

3o2 

327 

328 

329 

329 

33o 

33 1 

332 

333 

334 

335 

336 

337 

338 

338 

339 

TAIÎI.V",   II.  —  To  fiiul  the  time  T\  the  sum  of  the  radii  r-|->' ">  nnil  the  chonl  c  lieins  given. 


.'"uin  «r  llnJ  Kiulil   r-f  r". 


Chord 

c 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,1 1 
0,12 
o,i3 
,i4 

o,i5 
0,16 
0,17 
0,1b 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 

o,3a 
0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 

Oy43 

0,44 
0,45 

o,5o 
0,55 
0,60 
0,65 
0,70 

0,75 
o,bo 
0,85 
0,90 
0,95 
1,00 


1,69 


Dii)s  |.lil. 


O.OOU 

0.3-8 

o,756 
i.i34 
i,5ii 


2,267 
2,645 
3,023 
3,400 

3,7 
4,1 56 
4,533 
4,91 1 
5,289 

5,666 
6,044 
6,421 
6,-98 
7.176 

7,553 
7,930 
8,307 
8,684 
9,061 

9,438 
9,81 5 
0,191 
o,56fc 
0,944 

1,321 

1,697 
2,073 
2^449 
2,825 

3,20  ! 

3,577 
3,953 
4,328 
4,704 

5,079 
5,454 
5,829 
6,204 

6,5-8 

6,953 

8,b23 

20,689 

22,5  5o 

24,4o5 
26,255 

28,098 
29,934 
31,762 
33,582 
35,392 
37,193 


23 


1t 


1,4281 


1,70 


lliiys  |ilil'. 


0,CKX> 
0,379 

0,75b 

!,l3 

i,5i6 

1,895 
2,274 
2,653 
3,o3 
3,4 10 

3,789 
4,16b 
4,54- 
4,935 
5,3o4 

5,683 
6,061 
6,440 
6,818 
7,197 

7,575 
7,953 
8,332 
8,710 
9,088 

9.466 
9,844 
0,222 
o,5ç9 

o.y77 

1.354 

1,732 
2,10g 
2,4!-'6 
2,864 

3,241 
3,617 
3,994 
4,371 
4,747 

5,124 
5,5oo 
5,876 

6,252 

6,628 
7,004 

8,879 

20,75 1 

22,618 
34,479 

26,335 
28,1 

30,026 
3 1,860 
33,686 
35,5o3 
37,3io 


1,4450 


1,71 


U.iys  |dif. 


0,000 
o,38o 
0,-60 
1 , 1 4o 
i,5';o 

1 .900 
2,280 

2,6()0 

3,o4o 
3,420 

3,800 

4,lb0 

4,56o 
4,940 
5,320 

5,700 
6,079 
6,459 
6,83b 
7,21b 

7.597 

7.97 

8,356 

8,735 

9.115 

9.494 
9,873 
0,252 
o,63i 
1,009 

1,388 
1,76' 
2,145 

2,523 

2 ,909 

3,280 
3,658 
4,o36 
441 3 
4,79' 

5,1 6g 
5,546 
5,923 
6,3oo 
6,677 

7,o54 
8,936 
20,81 3 
23,686 
24,553 
26,414 

28,269 
3o,ii7 
3 1,958 
33,790 
35,6i4 
37,427 


23 
23 
25 

26 
56 

28 
39 

3c 
3i 

33 

33 

36 

3 

3fc 

3o 
4c 
4i 
43 
AA 

44 
46 
47 
46 

49 

5o 
56 
63 
67 
73 
80 

86 

9' 
98 
io4 
110 
"7 


1,72 


Itiiy.:  |dir 


0.000 
0^381 
0,-762 

i,i44 
1,525 

1,906 

2,28 

2,66b 

3,049 

3,43o 

3,811 
4.192 
4,573 
4,954 
5,335 

5,716 

6,097 
6,478 
6,858 
7.339 

7.620 
8,000 
8,38i 
8,761 
9,i4i 

9,522 
9«o2 
0,282 
0,662 
1,042 

1,421 
1,801 
2,181 
2,56o 
2,940 

3,3r9 
3,698 
4,077 
4,456 
4,835 

5,21 3 
5,593 
5,970 
6,348 
6,726 

7,104 

8.993 
20,875 
22,753 
24,626 
36,494 

28,355 
3o,2C9 
32,o56 
33,894 
35,724 
37,544 


39 
3(, 
3i 

33 

34 

35 

3 

3 

37 

39 
4i 
41 
45 
43 

45 
45 
47 
4t 
5c- 

5i 
56 
62 
68 

74 
76 

85 
9' 
97 
104 
ic.g 
116 


1,46211  1,4792 


0,000 
0,382 
0,765 

i,i47 

1.539 

1.911 
3,394 
3.676 

3,o58 
3^440 

3,833 
4,3o5 
4,587 

4,969 
5,35i 

5.733 
6,ii5 
6,497 
6,878 
7,360 

7,642 
8,023 
8,4o5 
8,787 
9,16b 


9.931 

0,3l2 

0,693 
1 ,074 

1,455 

1,836 
2,216 
2,597 
3.977 

3,358 

3,738 

4,11 

4,498 

4.878 

5,2 

5,637 
6.017 
6,396 
6,776 

7,i55 
9,048 
20,937 
22,821 
24,700 
26,573 

38/i4o 
3o,3oo 
33,i53 
33,998 
35,833 
37,660 


46 
4 
48 
49 

5o 
55 
61 

67 
73 
79 

85 
91 
97 

io3 
o 

116 


1,74 


Duys  |.lil. 


O,O0(' 

0.383 
0,767 
I.lSo 
1,534 

1,917 
2,3oo 
3,684 
3,067 
3,45o 

3,834 
4,317 
4.60U 
4x(S3 
5,366 

5,749 
6,i32 
6,5 1 5 
6,898 
7.381 

7.664 
8,047 
8,439 
8,812 
9.195 

9.577 

9.959 

0,34 

0,724 

1,106 

1,488 
1,870 

2,25? 

2,633 
3,oi5 

3,397 
3,778 
4,i59 
4,540 
4,931 

5,3o2 
5,683 
6,064 
6,444 
6,83 

7,2o5 
9,io3 
30,998 
22,888 
34i773 
26,653 

28,525 
30,391 

32,25o 

34,101 

35,943 

37.776 


0,OOC)0 

0,000 1 
o,ooo4 
0,00c  9 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,01  21 
0,01 44 
0,0169 
0,0196 

0,0225 
0,02 56 
0,0289 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
0,0481 
0,0539 
0,0576 


3t  0,0635 
0,0676 


1,49651  1,5138 


0.0739 
0,0784 
0,084 1 

o,ogoo 
0,0961 
0,1024 
0,1089 
0,1 156 

0,1225 
0,1296 
o,i3fc9 
0,1444 
0,1 521 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,2025 
0,2  5oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
0,6400 
0,7225 
lioo 
0,9035 


c" 


i- 

r  +  r' 

)^  or  T 

'-fr '■  = 

nrarly 

374 

375 

376 

377 

378 

379 

38o 

38 1 

382 

383 

384 

37 

38 

38 

38 

38 

38 

38 

38 

38 

38 

38 

75 

75 

75 

75 

76 

76 

76 

76 

76 

77 

77 

112 

ii3 

ii3 

ii3 

Ii3 

ii4 

114 

ii4 

ii5 

lib 

ii5 

i5o 

i5o 

i5o 

i5i 

i5i 

l52 

l52 

l52 

i53 

i53 

i54 

,87 

188 

188 

i8q 

189 

190 

190 

iqi 

191 

192 

192 

324 

225 

236 

236 

227 

227 

228 

339 

229 

23o 

23o 

262 

363 

263 

264 

265 

265 

266 

367 

267 

268 

269 

309 

Joo 

3oi 

3o2 

3o2 

3o3 

3o4 

3o5 

3o6 

3o6 

3o7 

337 

338 

338 

339 

340 

34i 

342 

343 

344 

345 

346 

l'rwp.  piirls  Inr  tin-  sum  ol'  tlic  Ituilii. 

■  I  3  I  3  I  4  I  5  I  6  I  7|8|9 


5i 

52 

53 
54 

55 
56 

57 
58 

59 

60 
61 
62 
63 
64 

65 
66 
67 
68 
69 

70 
80 

90 
100 


25  3o 


43  4q 
56 
54  63 
60  70 


35 

28 

35 

39 

26 

3o 

37 

3o 

37 

3i 

38 

32 

2q 

33 

39 

34 

3o 

M 

3i 

35 

23 
23 

34 

35 

26 

37 
28 

39 

3o 
3i 

32 

32 

33 

34 
35 

36 

37 
38 

39 
40 

4i 
4i 
43 
43 
44 


36 

37 
38 
38 
39 

40  45 

4i 

42 

43 

43 

44 
45 
46 
46 
47 


55  62 


90 


a8 


TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r  +  t",  and  the  chord  c  being  given. 

Sum  of  the  Radii  t  -\-r". 


Chord 

c. 


0,00 
0,01 
0,02 
o,o3 
0,04 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 

0,1  ! 
0,1  2 

0,1 3 
o,i4 

0,1 5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 

0,23 

0,24 

0,25 
0,26 
0,27 

0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
0,39 

o,4o 
0,41 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
0,61 
0,70 

0,75 
0,80 
o,85 
0,90 
0,95 
1,00 


1,75 


Days  |dif. 


0,000 
0,385 
0,769 
1, 1 54 
1,538 

1,922 
2,307 
2,691 
3,076 
3,460 

3,845 
4,229 
4,6i3 

4,997 
5,383 

5,766 
6,i5o 
6,534 
6,918 
7,3o2 

7,686 
8,070 
8,454 
8,837 
9,221 

9,6o5 
9,988 
0,371 
0,755 
i,i38 

1,521 
1,904 
2,287 
2,670 
3,o53 

3,435 

3,81 

4,200 

4,582 

4:965 

5,347 
5,728 
6,110 
6,492 
6,873 

7,255 
9' 1 59 
21,059 
22.95 
24,846 
26,730 

28,609 
3o,48? 
32,346 
34,2o3 
36,o53 
37,891 


1,76 


Days  |dif. 


1,5313 


0,000 
o,386 

0,771 
1, 1 57 
1,542 

1,928 
2,3i4 
2,699 
3,o85 
3,470 

3,856 
4,241 
4,626 
5,012 
5,397 

5,782 
6,168 
6,553 
6,938 
7,323 

7,708 
8,og3 
8,478 
8,863 
9>247 

9,632 
10,017 
io,4oi 
10,786 
11,170 

11,554 
11,938 

12,322 
12,706 
13,090 

i3,47 
i3,857 
i4,24i 
14,624 
1 5,008 

15,391 
i5,774 
i6,i57 
16,539 
16,922 

i7,3o4 
19,214 
21,120 
23,022 
24,918 
26,809 

28,69. 

30,572 

32,443 

34,3o6 

36, 160 

38,oo6 


1,77 


Days  [dit'. 


1 ,5488 


0,000 
0,387 
0,773 
1,160 
1,547 

1,933 
2,320 

2,707 
3,093 
3,480 

3,866 
4,253 
4,64o 
5,026 
5,412 

5.799 
6,i85 
6,571 
6,958 
7,344 

7,730 
8,116 
8,5o2 
8,888 
9,274 

9'659 
0,045 
0,43 1 
0,816 

1,202 

1,587 
1,972 
2,357 
2,743 
3,127 

3,5i2 
3,897 
4,282 
4,666 
5,o5i 

5,435 
5,819 
6.2o3 
6,587 
6,970 

7,354 
9,270 
21,181 
23,088 
24,991 
26,887 

28,778 
30,662 
32,539 
34,4oS 
36,269 
38,121 


1,78 


Days  |ilif. 


1,5665 


0,000 
o,388 
0,776 
i,i63 
i,55i 

1,939 
2,327 

2,714 
3,102 
3,490 

3,877 
4,265 
4,653 
5,o4o 
5,428 


16 

5,81 5 

18 

6,2o3 

19 

6,590 

19 

6,977 

21 

7,365 

22 

7,752 

23 

8,i3q 

24 

8,526 

25 

8,QI. 

26 

9,3oo 

9,687 

0,074 

0,460 

0,847 

1.233 

1,620 
2,006 
2,393 

2,779 
3,i65 

3,55i 
3,937 

4,322 

4,708 
5,093 

5,479 
5,864 
6.249 
6,634 
7,oJ9 

7,4o4 
9,325 
21,242 
23,1 55 
25,o63 
26,965 

28,862 
3o,75i 
32.634 
34,5io 
36,377 
38,235 


1,79 


Days  Idif. 


1,5842 


0,000 
0,389 
0,778 
1,167 
1,555 

1,944 
2,333 
2,722 
3,111 
3,5oo 

3,8 

4,277 

4,666 

5,o54 

5,443 

5,83 1 
6,220 
6,608 

6,997 
7,385 

7,774 
8,162 
8,55o 
8,938 
9,326 

9,7'4 
10,102 
10,490 
10,877 
11,265 

11,653 

12,o4o 
12,427 

I2,8i5 
1 3,202 

1 3,589 
13,976 
i4,363 
14,749 
i5,i36 

l5,522 

1 5,909 
16,395 
16,68 
17,067 

17,453 
19,380 
2i,3o3 

23,22! 

25,i35 
27,043 

28,945 

3o,f 

32,73o 

34,611 

36,484 

38,348 


49 
55 
60 
66 

71 

7 

83 

89 
95 
101 

107 
114 


1 ,6021 


1,80 

Days  Idif. 


0,000 
0,390 
0,780 
1,170 
l,56o 

i,95o 
2,34o 
2,73o 
3,119 
3,509 

3,899 
4,28g 

4,679 
5,068 
5,458 

5,848 
6,237 
6,627 
7,016 
7,406 

7,795 
8,i85 
8,574 
8,963 
9,352 

9,74 1 
io,i3o 
10,519 
10,908 
11,297 

11,685 
12,074 
12,462 
i2,85i 
13,239 

13,627 
i4,oi5 
i4,4o3 

14,791 
i5,i79 

1 5,566 
15,954 
16,341 
16,728 
I7,ii5 

i7,5o2 
19,435 
21,363 
23,287 
25,206 
27,120 

29,028 
30,930 
32,825 
34,712 
36.591 
38,462 


1 ,6200 


1,81 


Days  |dif. 


0,000 
0,391 
0,782 
1,173 
1,564 

1,955 
2,346 
2,737 
3,128 
3,519 

3,910 
4,3oi 
4,692 
5,082 
5,473 

5,864 
6,255 
6,645 
7,o36 
7^26 

7,817 
8,207 
8,598 
8,988 
9,378 

9,768 
0,1 58 
0,548 
0,938 
1,328 

1.718 
2,108 

2,497 
2,887 
3,276 

3,665 
4,o5. 
4,443 
4,832 
5,221 

5,610 

5,998 
6,387 
6,775 
7,i63 

7,55i 
9,489 

21,423 

23,3 

25,278 

27,198 

29,111 
31,019 
33.920 
34,81 3 
36,698 
38,575 


1,6381 


1,82 


Days  |dif. 


0,000 
0,392 
0,784 
1,176 

1,568 

1,961 
2,353 
2,745 
3,i37 
3,529 

3,921 
4,3i3 
4,7o5 
5,097 
5,488 

5,880 
6,272 
6,664 

7,o55 
7,447 

7,839 
8,23o 
8,621 
9,01 3 
9,4o4 

9,795 
0,187 
0,578 
0,969 
i,36o 

i,75o 

2,l4l 
2,532 

2,922 
3,3i3 

3, 703 
4,093 
4.4«3 
4,873 
5,263 

5,653 
6,043 
6,432 
6,822 
7,211 

7,600 
9,544 
21,483 
23,419 
25,349 
27,275 

29,194 

3i,io8 

33,01 

34,913 

36,8o5 

38,688 


21 
23 
34 
25 
26 

27 
28 

29 

3o 
3i 

33 
34 
34 
36 
36 

38 

39 
40 
42 
43 

43 
44 
46 
46 
48 

49 
54 
60 
65 

71 
76 

83 
88 

94 
101 
106 
1 12 


1,6562 


1,83 


Days  Idif. 


0,000 
0,393 
0,786 
1,180 
1,573 

1,966 
2,359 
2,752 
3,145 
3,538 

3,932 
4,325 
4,718 
5,111 
5,5o3 

5,896 
6,289 
6,682 

7,075 
7,467 

7,860 
8,253 
8,645 
9,o38 
9,43o 

9,822 

0,3l5 

0,607 

0,999 
1,391 

1,783 

3,175 
2,566 
3,958 
3,349 

3,74i 
4,i33 
4,523 
4,915 
5,3o6 

5,696 
6,087 
6.478 
6,868 
7,259 

7,649 
9,598 
21,543 
23,484 
25,420 
27,351 

29,277 
31,196 
33,108 
35,oi4 
36.911 
38.800 


1,6745 


1,84 


Days  |dif. 


0,000 
0,394 
0,789 
I,i83 

1,577 

1,971 
2,366 
2,760 
3,i54 
3,548 

3,942 
4,336 
4,73o 
5,124 
5,519 

5,912 
6,3o6 

6,700 

7,094 
7,488 

7,5 

8,275 

8,669 

9,062 

9,456 

9,849 
0,243 
o,636 
1,029 
1,422 


2,208 
2 ,60 1 
2,993 
3,386 

3,779 
4,171 
4,563 
4.956 
5,348 

5,740 
6,i3i 
6,523 
6,9 1 5 
7,3o6 

7,698 
g,652 
2 1 ,6o3 
23,549 
25,491 
27,428 

29,359 
3i,284 
33,202 
35,ii3 
37,017 
38,912 


1,6928 


0,0000 
0,0001 

o,ooo4 
0,0009 
0,0016 

0,0025 
,oo36 
0,0049 
0,0064 
0,0081 

0,0100 
0,0121 
o,oi44 
0,0169 
0,01  g6 

0,0225 
,02  56 

O,028_ 

o,o324 
o,o36i 

o,o4oo 
o,o44i 
0,0484 
0,0529 
0,0576 

0,0625 
0,0676 
0,072g 
0,0784 
0,084 1 

o.ogoo 
0,0961 
0,1024 
o,ic 
0,1 156 

0,1225 
0,1296 
0,1369 
0,1 444 

0,l52I 

1600 
0,1681 

1764 
0,1849 
0,1936 

0,2035 
o,25oo 
o,3o35 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 

0,8lCK> 

0,9025 
1 ,0000 


cr 


(r  -1-  r")»  or  r''   +  r"^   nearly. 


38 1 

382 

383 

384 

385 

386 

387 

388 

38g 

3go 

3gi 

392 

3g3 

3g4 

3g5 

38 

38 

38 

38 

39 

3q 

39 

39 

39 

39 

39 

3q 

39 

3q 

40 

76 

76 

77 

77 

77 

77 

77 

78 

78 

78 

78 

78 

79 

79 

79 

ii4 

ii5 

ii5 

•  ii5 

116 

116 

116 

116 

117 

117 

117 

118 

118 

118 

"9 

162 

i53 

1 53 

1 54 

1 54 

i54 

i55 

1 55 

i56 

1 56 

i56 

i57 

1 57 

1 58 

1 58 

191 

191 

192 

192 

193 

193 

194 

194 

iq5 

iq5 

iq6 

196 

197 

197 

igS 

229 

32g 

23o 

23o 

23l 

232 

232 

233 

333 

334 

235 

235 

236 

236 

237 

267 

367 

268 

260 

370 

270 

271 

272 

373 

273 

374 

274 

275 

276 

277 

3o5 

3o6 

3o6 

307 

3o8 

309 

3io 

3io 

3ii 

3l3 

3i3 

3i4 

3i4 

3i5 

3i6 

343 

344 

345 

346 

.347 

347 

348 

349 

35o 

35i 

352 

353 

354 

355 

356 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-f-r",  and  the  chord  c  being  given. 


Sum  of  the  Uailii  r-f-r". 


Chord 
C. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
o,i3 
0,1 4 

o,r5 
0,16 
0,17 
0,18 


0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
o,3i 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 

0,43 
0,44 

0,45 

o,5o 
0,55 
0,60 
o,65 


0,75 
0.80 
o,85 
0,90 
0,95 


1,85 


Pays  Idii; 


0,000 
0,395 
0,-9 1 
J, 186 

1, 58 1 

1.977 

2,3 

2,767 
3,162 
3,558 

3,953 
4,348 
4,743 
5, 1 38 
5,533 

5,959 
6,324 
6,718 

7,Il3 

7,5o8 

7,903 
8,298 
8,692 
9,08- 
9,482 

9,876 
10,270 
io,665 
1 1 ,059 
11,453 

11,847 
12.241 
12,635 
r  3,029 
1 3,423 

i3,8i6 

l4,2IO 

i4,6o3 

14,996 
15,39.: 

1 5,783 
16,176 
i6,568 
16.961 
17,354 

17.746 
19,706 
21,662 
23,6i4 
25,562 
27,5o4 


1,86 


Dnya  |dir 


29 ,44 1 
3 1,372 
33,296 

35,2i3 
37,122 
39,023 


0,000 
0,396 

0,793 
I,l8q 

1,586 

1,982 

2,378 
2,775 
3,171 
3,567 

3.964 
4,36o 
4,756 
5,i53 
5,548 

5,945 
6,341 
6,737 
7,i33 
7,529 

7,9'4 

8,320 

8,716 
9,112 

g,5o7 

9,903 
10,398 
10,694 
1 1 ,089 
11,484 

11,879 
12,274 
12,669 
13,064 
13,459 

1 3,854 
14,248 
14,643 
i5,o37 
i5,43i 

15,826 
16,230 
i6,6i3 

17,007 
17,401 

17,794 
19,760 
21,722 
23,679 
35,632 

27.58o 


1,87 


Days  lilil'. 


1,7113 


29,533 
31.459 
33,389 

35,3 12 
37,227 


i3 
i4 
i5 

16 

17 
18 

19 
20 

22 

23 
23 

24 
26 

26 
28 
28 

3c. 
3i 

33 

34 
35 
36 
36 

3 

39 

39 

4i 

42 

42 
43 
45 
46 
4- 

49 
54 

59 
65 

71 
76 


39, 1 34I 1 1 1 


1,7298 


0,000 
0,39' 
0,795 
1,192 
1,590 

1,987 
2,385 

2,7' 

3,1. 
3,5 

3,974 
4,372 
4,7(19 
5.160 
5,563 

5,961 
6,358 
6,755 
7,i52 
7,549 

7,946 
8.343 
8,739 
9,1 36 
9,533 

9,929 
10,326 
10,733 
11,119 
ii,5i5 

11,911 
1 3 ,3o8 
12,704 
i3,ioo 
13,495 

13.89 
14,387 
14,682 
15,078 
1 5,473 

1 5,868 
16,263 
i6,658 
i7,o53 
17,44s 

17.843 
19,814 
21,781 
23,744 
25,7o3 
27,656 


39,604 
31.547 
33.482 
35,4ii 
37,332 
39,245 


1,88 


Days  Itlif. 


1 ,7485 


0,000 

0,399 

o,"9' 
1 , 1 96 

1,594 
1,993 

2,391 
2,790 

3,188 

3,586 

3.9S5 
4,383 
4.783 
5,180 
5,578 

5,976 
6,375 
6,773 
7,171 
7,569 

7.967 
8,365 
8,763 
9,161 
9,558 

9,956 
10,354 
io,75i 
11,149 
11,546 

11,943 
13,341 
12,738 
i3,i35 
i3,532 

13.928 
i4,325 
14,722 
i5,ii8 
i5,5i5 

15,911 
i6,3o7 
i6,7o3 

17,099 
17,495 

17,891 
19,867 
21,840 
23,809 
25,773 
37,732 

29,686 
3i,633 
33,575 
35,5io 
37,437 
39,356 


1,89 

Days  |dif. 


1,7672 


0,000 
0,400 
o,"99 

',"99 
1,598 

1,998 

2,397 

2,797 
3,197 
3,596 

3,995 
4,395 
4,794 
5,194 
5,593 

5,992 
6,393 
0,791 
7,190 
7,589 

7,988 
8,387 
8,786 
9,i85 
9,584 

9,983 
1 0,38 1 
10,780 
11,178 
11,577 

11,975 
12,373 
12,772 
13,170 
1 3,568 

13,966 
1 4,363 
14,761 
1 5,1 59 
1 5,556 

1 5,954 
i6,35i 
16,748 
17,145 
17,543 

17,939 
19,931 
21,899 
23,873 
25,843 
27,807 


_^90^ 

Daya  jdif. 


0,000 
o,4oi 
0,801 
1 ,302 
i,6o3 

2,oo3 
2,4o4 
2,804 
3,2o5 
3,606 


29,767 

3l,720 
33,667 
35,608 
37,541 
39,466 


4,006 
4,407 
4,807 

5,207  i4 
5,608  i5 

6,008  16 
16 
I 
19 


6,409 
6,809 
7,209 
7,609 

8,009 
8,409 
8,809 
9,209 
9,609 

10,009 
10,409 
10,808 
11,208 
1 1 ,608 

13,007 

I2,4o6 

12,806 

t3,2o5 
i3,6o4 

i4,oo3 
i4,4o2 
1 4,800 
15,199 
15,598 

15,996 
16,394 
16,793 
17,191 
17,589 

17,987 
19,974 
21,958 
23,937 
25,912 
27,883 


3Q,848 
3 1,807 
33,76<i 
35,706 
37,645 
39,576 


o,ot,oo 
0,0001 

0,CKK,4 

o,o<:)09 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,0081 

0,01 00 
0,01 2 1 
0,01 44 
0,0169 
0,0196 

0,0225 
0,0256 
0,0289 
0,0324 
o,o36i 

o,o4oo 
o,o44i 
0,0484 
0,0529 


21 
23 
24 

25 

36  0,0576 


1,7861     1,8050 


0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

0,0900 
0,0961 
0,1094 

o.io8f) 
o,  1 1 56 

0,1225 
0,1296 
0,1369 
o,i444 

l52I 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,3025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5635 
o,64oo 
0,7335 
0,8100 
0,9025 
1 ,0000 


/•a 


(  r  -(-  r  "  J  ^  or  r^  -f"  ^  '  ^  nearly. 


392 

393 

394 

395 

396 

397 

398 

399 

400 

4oi 

I 

3q 

3q 

3q 

4o 

40 

4o 

40 

40 

40 

4o 

2 

78 

"§ 

79 

79 

79 

79 

80 

80 

80 

80 

3 

118 

118 

118 

"9 

119 

119 

"9 

120 

120 

120 

4 

1 57 

1 57 

1 58 

1 58 

1 58 

l5q 

l5q 

160 

160 

160 

5 

196 

197 

197 

iq8 

198 

199 

300 

200 

201 

b 

235 

236 

236 

237 

238 

238 

239 

239 

240 

241 

7 

274 

275 

276 

277 

277 

278 

279 

279 

280 

281 

8 

3i4 

3i4 

3i5 

3i6 

3l7 

3i8 

3i8 

3iq 

320 

32  1 

9 

353 

354 

355 

356 

356 

357 

358 

359 

36o 

36 1 

Trop,  ports  for  tlie  sum  of  the  Itadii. 
1  I  2  I  3  I  4  I  5  I  6  I  7  I  8     9 


70 
80 

90 
100 


7 

I  1  17 
17 
17 
18 


10 

!  I  l3 

1 1  i3 
i4 
i4 

i3  i5 
i3  16 
14  16 

i4 
i5 

i5 
16 
16 

17 
17 

18 
18 
J9 
19 
20  23 


23 


25 

26 
26 

3  1   37 
2  2   37 


3o  4o 


35 
35 
26 
36 

27 
28 
28 

29 
39 

3o 
3i 
3i 

32 
32 

3 

34 

34 

3 

35 

36 

37 
37 
38 
38 

39 
40 
4o 
4i 
4i 

43 
48 
54 
60 


13 

i3 

14 
i4 
i5 
16 
17 

18 

'9 
30 
21 
22 

23 
23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 
39 
4o 


4i 
4i 
42 
43 
39  44 


TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-\-r",  and  the  chord  c  being  given. 


Sum  of  the  Radii  r-|-'*  '• 


Cliord 
C. 


0,00 
0,01 
0.02 
o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
o,i3 
o,i4 

o,i5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
o,4> 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75' 
0,80 
0,85 
0,90 
0,95 
1 ,00 


1,91     I     1,92 

1 I  i.i-         n..,.=  i.i; 


Days  |.lif. 


0,000 
0.402 
o',8o3 
I,2o5 

1,607 

2,008 

2,4lO 
2,812 

3,2 1 3 
3,61 5 

4,017 
4,418 
4,820 
5,221 
5,623 

6,024 
6,435 
6,827 
7,228 
7,629 

8.o3o 
8,432 
8,833 
9,234 
9,635 

io,o35 
10,436 
10,837 
11,238 
11,638 

12,039 
12,439 
12,839 
1 3,240 
1 3,640 

i4,o4o 
i4,44o 
i4,84o 
15,239 
1 5,639 


16,039   42 

i6,438 

i6,837 

17,236 

17,635 


Days  l.ar. 


i8,o34 
20,027 
22,016 
24,001 
25.982 
27,958 

29,928 
31,893 
33,852 
35,804 
37,748 
39.685 


47 


0,000 
o,4o3 
o,8o5 
1,208 
1,61 1 

2,Ol4 

3,4i6 
2,819 
3,222 
3,624 

4,027 
4,43o 
4,832 
5,235 
5,637 

6,o4o 
6,442 
6,845 
7,247 
7>649 

8,o5i 
8.454 
8,856 
9.2  58 
9,660 

10,062 
10,464 
io,865 
1 1,267 
1 1 ,66() 

12,070 
12,472 
12,873 
i3,274 
13,676 

14,077 
14,478 
14,87g 
1 5,379 
1 5,680 

16,081 
16,481 
16,882 
17,282 
17,682 


20,080 
22,074 
24,065 
26,05 1 
28,032 

30,009 
31,979 
33,943 
35,901 
37,85! 
39,794 


23 
23 
24 
25 

26 

27 
29 
29 

3^ 

32 
32 

34 

3 
35 

37 
38 

39 
4o 
4i 

42 
43 
44 
45 
46 

47 
53 

59 
64 

69 

75 

80 
86 
9 
97 
io3 


1,93 


Uays  |(lir. 


0,000 

o.4o4 
0,808 
1,211 
1, 61 5 

2,019 
3,423 
2,826 
3.23o 
3,634 

4,o38 
4.441 
4,845 
5,248 
5,652 

6,o55 
6,459 
6,862 

7,266 
7,669 

8,072 
8,476 
8,879 
9,282 
9,685 

10,088 
10,491 
10,894 
1 1,296 
1 1 ,699 

12,102 
i2,5o4 
13,907 
1 3,309 
i3,7i  I 

i4,ii4 
i4,5i6 
14,918 
1 5,3 19 
15,721 

16,123 
16,524 
16,926 
17,337 
17,728 

18,129 
20,1 33 

22,l33 

24,139 

26,1  2( 

28,107 

30,089 
3  2, 06  5 
34,o35 
35,998 
37,9^4 


109139,903 


0,000 
o.4o5 
0,810 
1,21 5 
1,619 

3,024 
2.439 
3,834 
3.239 
3,643 

4,048 
4.453 
4,857 
5,262 
5,667 

6,071 
6,476 
6,880 
7,285 
7,689 

8,093 
8,498 
8,902 
9,3o6 
9,710 

10, 1 14 
1 0,5 18 
10,922 
r  1,326 
1 1,730 

i2,i33 
12,537 
1 2 .940 

1 3, 34.' 
1 3,747 

i4.i5o 
i4,553 
14,956 
i5,«9 
15,762 


16,165  42 

16,567 

16,970 

17,372 

■7,775 


1,8241  I  1,84321  1,8625  |  1,8818 


18,177 
20,186 
22,191 
24,192 
26.189 

28,i8"i 

30,169 
32,i5o 
34,136 
36,095 
38,o57 
4o,oi  1 


1,95 


Days  |dir. 


0,000 
0,406 
0,8 13 
1,218 
1,634 

2.029 

2^435 
3, 84 1 
3,347 
3,653 

4,o58 
4,464 
4,870 
5,276 
5,681 

6,087 
6,492 
6,898 
7,3o3 
7,709 

8,ii4 
8,520 
8,925 
g,33o 
9,735 

io.i4o 
10,545 
10.950 
11,355 
1 1,760 

I2,i65 
12,569 
13,974 
1  i,J7- 
I  3,783 

14,187 
14,591 
14,995 
15,399 
i5,8o3 


1,96 


Days  |iiif. 


16,207 

42 

i6.6[o 

43 

17,014 

44 

17,417 

45 

17,821 

46 

18,224 

47 

20,2  38 

52 

23,249 

57 

24,255 

6A 

26,258 

68 

28,256 

74 

3o,248 

80 

32,236 

85 

34,217 

90 

36,192 

96 

38,1 59 

102 

40,120 

107 

1,90 

13 

0,000 

0,407 
0,814 

1,231 
1,628 

2,o35 
2,44i 
3.848 
3.255 
3,662 

4,069 
4,476 
4,882 
5,289 
5,696 

6,102 
6,509 
6,916 

7,323 

7,729 

8,i35 
8.541 
8,948 
9,354 
9,760 

io,i66 
10,573 
10,978 
11,384 
11,790 

13,196 

I  3, 603 
1 3,007 

i3,4i3 
i3,8i8 

l4,333 
14,629 

i5,o34 
15,439 


41  1 5,844 


16,349 
16.653 
7,o58 
17,463 
17,867 

18,27 
290 

22,3o6 

24,319 
26,326 

28,330 

3o,328 

32,321 

34,307 

36,2. 
38,36i 


62 

69 

73 

79 
84 

9' 
96 

_  _, 102 

40,3371  Ï08 


1,97 

Unya  |ilil7 


0,000 
0,408 
0,816 
1,224 

1,632 

2,o4o 

3,448 
2,856 
3,363 
3,671 

4.079 

4,487 

4,89 

5,3o3 

5,710 

6,118 
6,526 
6,933 
7,341 
7,748 

8,1 56 
8,563 
8,971 
9,378 
9,785 

10,192 
10,599 
1 1 ,006 
ii,4i3 
11,820 

12,227 
13,634 
i3,o4o 
1 3,447 
1 3,853 

14,260 
1 4,666 

I  5,07 3 
15,478 
I  5,884 

16,290 
16,696 
17,102 
17,507 
17,913 

18,3  18 
20,343 
22,364 

24,38 1 
26,395 
28,4o3 


1 ,9208 


3i 

32 

34 
34 
36 

36 
38 

39 
4o 
4i 

42 
43 
43 
45 
46 

47 

53 

57 
63 
68 
74 


1,98 

Days  Idtl'. 


3o,4o7     79 

32,4o5    " 

34,398 

36,384 
38,363 
40,335 


0,000 
0,409 
0,818 
1,227 
1,636 

2,o45 
2,454 
3,863 
3,373 
3,681 

4,090 
4,498 
4.907 
5,3i6 
5,735 

6, 1 33 
6,542 
6,951 
7,359 
7,768 

8,176 
8,58 

8,993 
9,403 
9,810 

10,218 
10,626 
1 1  ,o34 
ii,'!43 
ii,85o 

12,258 

12,666 
13,074 
i3,48i 
13,889 

i4,2g6 
14,704 
i5,ii  I 
i5,5i8 
i5,935 

16,332 
16,739 
17,145 
17,552 
17,959 

i8,365 
20,395 
22,421 
24,444 
26,463 
28,477 

3o,486 
32,490 
34,488 
36,48o 
38,464 
40,442 


1,9405 


1,99 


Days  jdir. 


17 


0,000 
0,4 10 
0,820 
i,23o 
i,64o 

3,o5o 
3,460 
2,870 
3,280 
3,690 

4,100 
4,5io 
4,930 
5,339 
5,739 

6,149 
6,55q 
6,968 
7,378 
7,788 

8,197 
8,607 
g,oi6 
9,435 
9,835 


10,244 
10,653 
1 1 ,062 
11,471    29 
1,880    3o 


2,00 


Day*  |dif. 


1 ,9602 


12,289 
1 2 ,698 

i3,i07 
i3,5i5 
13,924 

i4,332 
i4,74i 
i5,i4o 
i5,557 
15,965 

16,373 

16,781 

17,1 

17,597 

18,004 

l8,4l2 

30,447 
22,479 
34,507 
36,53 1 
28,550 

3o,565 
32,574 
34,578 
36,575 
38,566 
40,549 


0,000 
0,4 1 1 
0,822 
1,233 
1,644 

2,o55 
3,466 

2,877 

3,2 

3,699 

4.110 
4,531 
4,932 
5,343 
5,754 

6,164 
6,575 
6,986 

7,397 
7,807 

8,218 
8,628 
9,039 
9,449 
9,859 

10,270 
10,680 
1 1 ,090 
1 1 ,5oo 
11,910 

12,320 
i2,73ci 
i3,i4o 
i3,549 
13,959 


37  14,369 

"     14,778 

15,187 

15,597 

16,006 

i6,4!5 
16,824 
17,333 
17,641 
i8,o5o 

i8,458 
20,499 

32,536 

24,569 
26,59g 

28,624 

3o,644 
33,658 
34,667 
36,670 
38,666 
4o,655 


37 
38 
4o 
4i 

43 
43 
43 
44 
46 

46 

53 

57 
63 
68 

74 

79 
84 
89 
95 

100 
106 


1,9801 


0,0000 
0,0001 

o,ooo4 
0,0009 
0,0016 

0,0035 
o,oo36 
o,oo4g 
0,0064 
0,008 1 

0,0100 

0,01  3  1 

0,01 44 
0,01 6g 
0,0196 

0,0225 
o,o256 
0,0289 
o,o324 
o,o36 1 

o,o4oo 
0,044 1 
o,o484 
o,o52g 
0,0576 

0,0625 
0,0676 
0,072g 
0,0784 


3o  0,08 


2,0000 


0,0900 
0,0961 
0,1024 
0,1089 
0,11 56 

0,1225 
0,1296 
0,1369 
o,i444 
0,1 52  I 

0,1600 
0,16 
0,1764 
0,18  _ 
0,1936 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 


,  (r  4-  *■  "  )"  oi"  '■*  -\-  t'"^    nearly. 


399 

400 

4oi 

402 

4o3 

4o4 

4o5 

406 

407 

408 

409 

4io 

40 

4o 

4o 

40 

4o 

40 

4i 

41 

4i 

4i 

4i 

4i 

80 

80 

80 

80 

81 

81 

81 

81 

81 

82 

82 

82 

120 

120 

120 

121 

121 

121 

123 

122 

123 

122 

123 

123 

160 

160 

160 

161 

161 

162 

163 

162 

i63 

1 63 

1 64 

1 64 

30O 

200 

201 

201 

202 

202 

2o3 

203 

204 

2o4 

2o5 

2o5 

239 

340 

241 

341 

242 

243 

243 

244 

344 

245 

245 

246 

279 

280 

281 

281 

282 

283 

284 

284 

285 

286 

286 

287 

3iq 

330 

321 

322 

322 

323 

324 

325 

326 

326 

327 

328 

359 

36o 

36i 

362 

363 

364 

365 

365 

366 

367 

368 

369 

411 

4i 
82 

123 

164 
206 

347 
288 
339 
370 


TABLE   II.  —  To  fiiiil  the  time  T ;  the  sum  of  tlie  lailii  r-f-r",  ami  the  chord  c  being  given. 


^um  uf  the  Ru'iii  r-\-r". 


ChonI 
C. 


0,t)0 

0,0 1 

(1,02 

o,o3 
o,o4 

o,u5 
o,u6 
0,07 
0,08 
0,09 

0,10 
0,1 1 

0,12 

0,1 3 
0,1 4 

0,1 5 
0,16 
17 
o,i8 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
o/ii 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 


0,75 
0,80 
o,85 
0,90 
0,95 
1. 00 


2,01 


2,060 
2,47s 

2,884 
3,296 
3,708 

4,120 
4,532 

5,356 
5,768 

6,180 
6,592 
7,oo3 
-,4i5 
7.827 

8,238 
8,65o 
9.061 
9.473 
9,884 

io,2g5 
10.707 

11,529 
1 1 ,940 

i2,35i 
12,762 
13,173 
1 3,583 
1 3,994 

i4,4o5 
i4,8i5 

l5,225 

1 5,636 
i6,o46 

1 6,456 
16,866 
17,276 
17,686 
18,095 

i8,5o5 
2o,55o 
22,593 
24,632 
26,666 
28,697 

30,722 
32,742 
34.757 
36,765 
38,767 
40,762 


■2,0-2 


Duys  Idii; 


2,0201 


0,000 

0,4 1 3 
0,826 
1,239 
1,652 

2,o65 

2,479 
2,892 
3,3o5 
3,718 

4,i3i 
4,544 
4,957 
5,369 
5,782 

6,195 
6,608 
7,021 
7,433 
7,846 

8,259 
8.671 
9,084 
9.496 
9,909 

10,321 
10,733 
1 1,146 
11,558 
11,970 

12,382 

12,794 
1 3,206 
1 3,61 7 
i4,02g 

i4,44i 
i4,852 
1 5,264 
15,675 
16,086 

16,497 
16,908 
17,319 
17,730 
i8,i4o 

i8,55i 
20,602 

22,65o 

24,694 

26,734 
28,769 

3o,8oo 
32,826 
34,846 
36,86o 
38,86- 
40,868 


2,03 


Dats  |dif. 


2,0402 


0,000 
0,4 14 
0,828 
1,242 

1 ,656 

2,071 
2,485 
2,899 
3,3i3 
3,727 

4,i4i 
4.555 
4,969 
5,383 
5,797 

6,211 
6,624 
7,o38 
7,452 
7,866 

8,270 
8,693 
9,106 
9,520 
9,933 

0,347 
0,760 

1,173 

1,586 
2,000 

2,4i3 
2,825 
3,238 
3,65 1 
4,064 

4,476 
4.889 
5,3oi 

5,7 
6,126 

6,538 
6,95o 
7,362 

7,774 
8,186 

■8,597 
20,654 
22,706 
24,756 
26,801 
28,842 

30,878 
32,909 
34,935 
36,954 
38,967 
40,973 


2,04 


Oays  Id  if. 


2,0605 


0,000 

0,4 1 5 
o,83o 
1,245 
1,661 

2,076 
2,491 
2,906 
3,321 
3,736 

4,i5i 
4,566 
4,q8l 
5,39(i 
5,811 

6,226 
6,641 
7,o55 
7,470 
7,885 

8,3oo 
8,714 
9,129 
9,543 
9,958 

10,372 
10,787 
11,201 
II, 61 5 
12,029 

12,443 
12,857 
13,271 
1 3,685 
14,099 

i4,5i2 
14,926 
15,339 
i5,753 
16,166 

16,579 
16,992 
i7,4ù5 
17,818 
i8,23i 

18,643 
20,705 

2  2,763 
24,81 
26,868 
28,915 

30,956 
32,993 
35,023 
37,048 
39,067 
41,079 


2,05 


Dnys  |ilir. 


2,0808 


0,000 
o,4i6 
o,832 
1 ,248 
1,665 

2,081 
2,497 
2,913 
3,32q 
3,74b 

4,161 
4,577 
4,993 
5,409 
5,825 

6,241 
6,657 
7,073 
7,489 
7,904 

8,320 
8,736 
9,i5i 
9,567 
9,983 

0,398 
0,81 3 

l,22i 

1,644 
2,059 

2,47- 
2,88( 
3,3o4 
3,719 
4,i33 

4,548 
4,963 
5,377 
5,791 
6,206 

6,620 
7,o34 
7.448 
7,862 
8,276 


20,756 
22,819 
24,879 
26,935 
28,987 

3i,o34 
33,075 
35,112 
37,142 
39,166 

4i,r 


2,06 


Days  )<lit'. 


2,1013 


0,000 

0,4 17 

0,834 

1,252 
1,669 

2,086 

2,5o3 
2,920 
3,337 
3,754 

4,171 
4,588 
5,oo5 
5,422 
5,839 

6,256 
6,673 
7,090 
7,5o7 
7,924 

8,34o 
8,757 
9, '74 
9,590 
10,007 

10,423 
io,83g 
11,256 
11.672 
12,088 

i2,5o4 
12,920 
1 3,336 
i3,752 
14.168 

i4,584 

14,999 
i5,4i5 
i5,83o 
16,245 

16,661 
17,076 
17,491 
17,906 
18,32 

18,735 
20,807 
22,876 
24,g4i 
27,002 
29,o5g 

3i,iii 
33,i58 
35,200 
37,236 
39,265 
41,288 


0,0000 
0,0001 
0,0004 
o,ooog 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,0081 

0,0100 
0,01  2  I 
0,01 44 
o,uifk) 
0,0196 

0,0225 
0,0256 
0,0289 
o,o324 
o,o36 1 

o,o4oo 
0,044 1 
0,0484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

0,0900 
0,09!)  1 
0,1024 
0,1089 
0,11 56 

0,1225 
0,1296 
0,1369 
0,1 444 

0,l521 

o,  1 600 
0,1681 
0,1764 
0,1849 
o,ig36 

0,2025 
0,2  5oo 
o,3o25 
o,36oo 
0,4225 
o,4goo 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 


2.1218 


5   ■  (r  -f-  r  "  )  ^  or  r^  -{-  r"^  nearly. 


409 

410 

4ii 

4l2 

4i3 

4i4 

4i5 

416 

417 

4i8 

4i 

4i 

4i 

4i 

4i 

4i 

42 

42 

42 

42 

82 

82 

82 

82 

83 

83 

83 

83 

83 

84 

123 

123 

123 

124 

124 

124 

125 

125 

125 

J25 

164 

164 

i64 

16!) 

i65 

166 

166 

166 

167 

167 

2o5 

2o5 

206 

206 

207 

207 

208 

208 

209 

200 

245 

246 

247 

247 

248 

248 

249 

250 

250 

25Ï 

286 

287 

288 

288 

289 

290 

291 

2QI 

292 

2g3 

327 

328 

329 

33o 

33o 

33 1 

332 

333 

334 

334 

368 

369 

370 

371 

372 

373 

374 

374 

375 

376 

Prup.  purts  fur  tlin  sum  uf  tho  Kudii. 

I |2|3|4  |5|6|7|8|g 

I 
2 

3 

4 


22 

23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 

33 
34 

35 
36 

37 
38 

39 

40 
41 
42 
43 
44 

45 
46 
47 
48 

49 

5o 
5i 

52 

53 
54 

55 
56 

57 
58 

59 

60 
61 
62 
63 
64 

65 
66 

67 
68 

69 

70 
80 

90 
100 


I 

I 

I 

I 

2 

2 

2 

3 

3 

4 

4 

4 

4 

5 

5 

6 

5 

6 

6 

7 

7 

8 

7 

8 

8 

9 

8 

10 

9 

1  1 

10 

1  1 

10 

12 

1 1 

i3 

1 1 

i3 

12 

i4 

i3 

i5 

i3 

i5 

i4 

16 

i4 

17 

i5 

18 

16 

18 

16 

'9 

17 

20 

17 

20 

18 

21 

'9 

22 

iq 

22 

20 

23 

20 

24 

21 

25 

22 

25 

22 

26 

23 

27 

23 

27 

24 

28 

25 

29 

2b 

29 

26 

3o 

26 

3i 

27 

32 

28 

32 

28 

33 

2q 

34 

29 

M 

3o 

35 

3i 

36 

3i 

36 

32 

37 

32 

38 

33 

3q 

34 

3q 

M 

4o 

35 

4i 

35 

4i 

36 

42 

37 

43 

37 

43 

38 

44 

38 

45 

3q 

46 

4o 

46 

4o 

47 

4i 

48 

4i 

48 

42 

4q 

48 

56 

54 
60 

63 

70 

a9 


FABLE  II 

—  To  find  the  time  T 

;  the  sum  of  the  radii 

r  +  r". 

and  the  chord  e 

being  give 

n. 

Sum  of  the  Rudii  r  -|-  r  ".                                                                                                              1 

Chord 
C. 

2,07 

Days  |iJil'. 

2,08 

2,09 

2,10 

2,11 

2,12 

2J3 

2,14 

2,15 

2,16 

Uavs  |i]if. 

Days  |dil'. 

Hays  lilif. 

Days 

dit". 

Days  Idif. 

Days  |.lif. 

Days  Idif. 

Days  |dif. 

Days  |dif. 

0,00 
0,01 

0,02 

o,o3 
o,o4 

0,000 
0,4 1 8 
0,836 
1,255 
1,673 

I 
2 
3 
4 

0,000 
0,419 
o,838 
1,258 
i>677 

I 
3 
3 
4 

0,000 
0,420 

o,84o 

1,261 
1,681 

I 
3 
3 

4 

0,000 
0,421 
0,843 
1,264 
1,685 

1 

3 

3 
4 

0,000 
0,422 

0,844 
1,267 
1,689 

I 
2 

3 
4 

0,000 
0,423 
0,846 
1.270 
1,693 

I 
3 
3 
4 

0,000 
0,434 

o,84& 

1,373 
1,697 

I 
2 
3 
4 

0,000 
0,425 
o,85o 
1,276 
1,701 

1 
2 
3 
4 

0,000 
0.426 
0352 
1,279 

i,7o5 

I 
2 
3 
4 

0,000 
0,427 
o,854 
1,282 

1 ,709 

1 
2 
2 
4 

0,0000 
0,0001 
o,ooo4 
o,ooog 
0,0016 

o,o5 
0,06 
0,07 
0,08 
0,09 

2,091 
2,5og 
2,927 
3,345 
3,763 

5 
6 

7 
8 

9 

2,096 
2,5i5 
2,934 
3,353 
3,772 

5 
6 

7 

8 

10 

2,101 
2,521 
2,941 

3,36i 
3,782 

5 
6 

7 
8 

9 

2,106 
2,537 
2,948 
3,369 
3,791 

5 
6 

7 
8 

9 

2,111 
2,533 
3,955 
3,377 
3,800 

5 
6 

7 
8 

9 

2,116 
2,539 
2,962 

3,385 
3,809 

5 
6 

7 
8 

9 

2,121 
2,545 
2,969 

3,3g3 
3,818 

5 
6 

7 
8 

9 

2,126 
2,55i 
2,976 
3,401 
3,827 

5 
6 

7 
8 
8 

2,l3l 

2,557 
2,983 

3,409 

3,835 

5 
6 

7 
8 

9 

2,i36 
2,563 

2,99" 
3,417 
3,844 

5 
6 

7 
8 

9 

0,0025 
o,ûo36 
0,0049 
0,0064 
0,0081 

0,10 
0,1 1 
0,12 
0,1 3 
o,i4 

4,181 
4,600 
5.018 
5,436 
5,854 

II 
II 
12 
i3 
i4 

4,192 
4,611 
5,o3o 

5,449 
5,868 

10 
II 
12 
i3 
i4 

4,203 
4,622 
5,042 
5,462 
5,882 

10 

I' 
12 

i3 

i4 

4,212 

4,633 
5,o54 
5,475 
5,896 

10 
II 

13 

i3 
i4 

4,232 

4,644 
5,066 
5,468 
5,910 

10 
II 
12 
i3 
14 

4,333 

4,655 
5,078 
5,5oi 
5,924 

10 
11 

13 

i3 

i4 

4.243 
4,666 
5,090 
5,5i4 
5.938 

10 
11 
12 
i3 
i4 

4,252 

4,677 

5,102 

5,527 
5,952 

10 
1 1 

13 

i3 
i4 

4.263 
4,688 
5,ii4 
5.540 
5,g66 

9 

1 1 
12 
i3 
i4 

4,271 
4.699 
5,126 
5,553 
5,980 

10 
10 
11 
12 

i3 

0,0100 
0,0121 
0,01 44 
0,0169 
0,0196 

0,1 5 
0,16 
0,17 
0,18 
0,19 

6,271 
6,689 
7,107 
7,525 
7.943 

16 

17 
17 
18 

'9 

6,287 
6,706 
7.124 
7.543 
7,962 

i5 
16 
i8 
18 
19 

6,3o2 
6,722 
7,142 
7,56 1 
7,981 

i5 
.6 

17 
18 

19 

6,3i7 
6.738 
7,159 

7.579 
8,oou 

i5 
16 

17 
18 

19 

6,332 
6,754 
7,176 
7,597 
8,019 

i5 
16 

■7 
18 

19 

6,347 
6,770 
7,193 
7,61 5 
8,o38 

i5 
16 

.7 
18 

19 

6,362 
6,786 
7,210 
7,633 
8,o57 

i5 
16 

17 
18 

19 

6,377 

6,802 
7,227 
7,65 1 
8,076 

i5 
16 
16 
18 
19 

6,3g3 
6,818 
7.243 
7,669 
8,og5 

14 
i5 
17 
if 
19 

6,/c6 
6,833 
7.360 
7,687 
8,114 

i5 
16 

17 
18 

'9 

0,0225 
0,0256 
0,0289 
o,o334 
o,o36i 

0,20 
0,21 
0,22 
0,23 
0,24 

8,36i 
8,778 
9,196 
9,61 3 
io,o3i 

20 
21 
22 
24 
24 

8,38 1 

8.799 
9,218 
9,637 
io,o55 

20 
22 
22 

23 

24 

8,401 
8,821 
9,240 
9,660 
10,079 

20 
21 
22 

23 
25 

8.421 
8,842 
9,262 
9,683 
1 0, 1  o4 

20 
21 
22 

23 

24 

8,44i 
8,863 
9,284 
9,706 
10,128 

20 
21 

23 
23 
34 

8,461 
8,884 
9,3o6 
9.729 

IO,l52 

20 
21 
22 

23 

24 

8,481 
8,905 
9,338 
9.753 
10,176 

20 

21 
22 
23 
23 

8,5oi 
8,936 
9,35o 
9.775 
10,199 

20 
21 
22 

23 

24 

8,521 

8,g47 
9,372 

9.798 
10,223 

20 
20 
22 

23 

24 

8,541 
8,967 
9,394 
9,831 
10,247 

19 

2J 
33 
22 
24 

o,o4oo 
o,o44i 
0,0484 
0,0529 
0,0576 

0,25 
0,26 
0,27 
0,28 
0,29 

10,448 
10,866 
11,283 
1 1 ,700 
12,1 18 

26 
26 

27 

=9 
29 

10,474 
10,892 
I  i,3io 

11,729 
I2,l47 

25 

26 
28 
28 
29 

10,499 
10,918 
11,338 

11,757 
12,176 

35 

26 

27 
28 

29 

10,524 
10,944 
11,365 
11,785 

I2,2o5 

25 

27 
27 
28 
29 

10,549 
10,971 
11,392 
ii,8i3 
12,234 

25 
26 

27 
28 

29 

10,574 
10,997 
11,419 
ii,84i 

13,363 

25 

26 

27 
28 

29 

io,5g9 
11,023 
1 1 .446 
1 1 ,869 
12,292 

25 
25 

27 
28 

29 

10,634 
ii,o48 
11,473 
11,897 

13,321 

25 

26 
27 
28 
29 

10,649 
11,074 
1 1 ,5oo 
11,925 
i2,35o 

25 

26 
36 
38 
29 

10,674 
11,100 
11,536 
1 1 ,953 
12,379 

34 
36 

27 
27 
29 

0,0625 
0,0676 
0,0729 
0,0784 
o,o84i 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

12,535 
12,952 
13,369 
13,786 
1 4,202 

3o 
3i 

32 

33 
35 

12,565 
12,983 
i3,4oi 
i3,8i9 
i4,237 

3o 
3i 

33 

33 

34 

12,595 
i3,oi4 
1 3,433 
i3,852 
14,271 

3o 

32 

33 

34 
34 

12,625 

i3,o46 
1 3,466 
1 3,886 
i4,3o5 

3i 
3i 

32 

33 
35 

12,656 
1 3,077 
1 3,498 
13,919 
1 4,340 

3o 
3i 

32 

33 
34 

12,686 
i3,io8 
i3,53o 
13,953 
14,374 

3o 
3i 

32 

33 
34 

13,716 
i3,i39 
i3,562 
i3,g85 
1 4,408 

3o 
3i 

32 

33 
34 

13,746 
13,170 
i3,5g4 
i4,oi8 
14,442 

29 

3i 

32 

33 
33 

12,775 

l3,201 

13,626 

i4,o5i 
i4,475 

3o 
3o 
3i 

32 

34 

i3,8o5 
i3,23i 
1 3,657 
i4,o83 
i4,5o9 

3o 
3i 

32 

33 
34 

o,ogoo 
0,0961 
0,1034 
0,1  o8g 
0,1 156 

0,35 
o,36 
0,37 
o,38 
0,39 

14,619 
i5,o36 
1 5,452 
15,869 
16,285 

36 
36 
38 
38 
40 

14.655 
15,072 
15,490 
15,907 
i6,325 

35 
37 
37 
39 

39 

14,690 
15,109 
i5,527 
1 5,946 
i6,364 

35 
36 

37 
38 

39 

14,725 
i5,i45 
i5,564 
15,984 
i6,4o3 

35 
36 
38 
38 
40 

14,760 
i5,i8i 
1 5,602 
16,022 
16,443 

35 
36 

37 
38 

39 

14,795 
l5.3I7 
1 5,639 
16,060 
16,482 

35 
36 

37 
38 

39 

i4.83o 
i5,253 
15,676 
16,098 
16,53 1 

35 
36 
37 
38 

39 

14,865 
1 5,28g 
i5,7i3 
16,1 36 
i6,56o 

35 
36 

37 

38 
39 

14,900 
1 5,325 
i5,75o 
16,174 
16,599 

35 
36 
36 
38 
38 

14,935 
i5,36i 
15,786 

l6,213 

1 6,637 

35 
35 

37 
38 

39 

0,1225 

o,i2g6 
0, 1 369 
0,1 444 

0,l52I 

o,4o 
0,41 
0,42 
0,43 
0,44 

16,701 
17,118 
17,534 
i7:95o 
i8,365 

4i 
4i 
42 
43 
45 

16,742 
17,159 
17,576 

17:993 
18,410 

40 
42 
43 

AA 
45 

16,782 
17,201 
17,619 
i8,o37 
18,455 

4i 
4i 
42 
43 
AA 

16,823 
17,242 
17,661 
18,080 
18,499 

40 
4i 
Ao 
43 
AA 

i6,863 
17,283 
17,703 
18.123 
18,543 

4o 
4i 
43 
AA 
45 

16,903 
17.324 
17,746 
18,167 
i8,588 

40 
4i 
43 
43 
AA 

i6,g43 
17,365 
17,788 
18,210 
i8,632 

4o 
4i 
42 
43 

AA 

i6,g83 
17,406 
i7,83o 
18,253 
18,676 

40 
4i 
41 
43 
AA 

17,023 
17.447 
17,871 
18,296 
18,720 

40 
4i 
42 

42 
43 

i7,o63 
17,488 
17,913 
i8,338 
18,763 

39 
4i 
42 
43 
AA 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,45 

0,5r) 

0,55 
0,60 
0,65 
0,70 

18,781 
20,858 
22,932 

25,002 
37,06g 

29,i3i 

46 
5i 
56 
61 
66 
71 

18,827 
20,909 
22,988 
25,o63 
27,i35 
29,202 

45 
5i 
56 
61 
66 
72 

18,872 
20,960 
2  3,o44 
25,124 
27,201 
29,274 

46 
5o 
55 
61 
66 
71 

18,918 
21,010 
33.09g 
25;i85 
27,267 
39,345 

45 
5i 
56 
61 
66 
71 

18,963 
21,061 
23,i55 
25,246 
27,333 
29,416 

45 
5o 
55 
61 
66 
71 

19,008 
21,1 11 
23,210 
25,3o7 
27,399 
29,487 

46 
5o 
56 
60 
66 
71 

19,054 

31, 161 

23,366 
35,367 

37,465 
29,558 

45 
5o 
55 
60 
65 
71 

19.099 
21,211 

23,321 

25,437 
27,530 

29.639 

AA 
5o 
55 
60 
65 
70 

19,143 
21,261 
23,376 
25,487 
27,595 
29.699 

45 
5o 
55 
60 
65 
70 

19,188 

2I,3lI 

23,43 1 

25,547 
27,660 
29,769 

45 
5o 
55 
60 
65 
70 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,75 
0,80 
o,85 
0,90 
0,95 
1,00 

3i,i88 
33,241 
35,288 
37,329 
39,364 
41,393 

77 
82 
88 
93 
99 
io4 

3 1, 265 
33,323 
35,376 
37,422 
39,463 
41,497 

77 
82 
8-^ 
93 
98 
io4 

31,342 
33,4o5 
35,463 
37,5i5 
39,561 
41,601 

77 
82 

87 

93 

98 
io3 

3i,4i9 
33,487 
35,55o 
37.608 
39,65g 
41,704 

76 
82 
87 
92 
98 
io4 

31.495 
33,56q 
35,637 
37,700 
39.757 
41,808 

76 

81 

87 

92 

98 
io3 

31,571 
33,65o 
35,724 
37.792 
39,855 

41,911 

76 
83 
87 
92 
97 

103 

3 1, 647 
33,732 
35,811 
37,884 
39,952 
42,oi3 

76 
81 
86 
92 
97 
io3 

3i,723 
33,8i3 
35,897 
37,976 
40,049 
42,116 

76 
80 
86 
92 
97 
102 

3 1,799 
33,8g3 
35,983 
38,o68 
4o.i46 
42,218 

75 
81 
86 
9' 
97 
102 

31,874 
33,g74 
36,o6g 
38,1 59 
40,243 
42,320 

75 
81 
86 

96 
102 

o,5635 
o,64oo 
0,7325 
0,8100 
0,9025 
1 ,0000 

2,1425 

2,1632 

2,1841 

2,2050 

2,2261  ' 

2,2472 

2,2685 1 

2,2898 1 

2,31131 

2,3328 1  c2     1 

.  (1-  -\-  r")''    or   ?•=  4.  r"»  nearly. 


4i5 

4i6 

417 

4i8 

419 

420 

421 

422 

423 

424 

425 

426 

437 

428 

42 

42 

42 

42 

42 

42 

42 

43 

42 

42 

43 

43 

43 

43 

83 

83 

83 

84 

84 

84 

84 

84 

85 

85 

85 

85 

85 

86 

125 

125 

125 

125 

136 

136 

126 

137 

127 

127 

128 

128 

128 

128 

166 

166 

167 

167 

168 

168 

168 

169 

169 

170 

170 

170 

171 

171 

208 

208 

209 

200 

210 

210 

211 

211 

212 

212 

2l3 

3l3 

2l4 

2l4 

249 

35o 

25o 

25I 

25l 

252 

253 

253 

254 

2  54 

255 

256 

356 

257 

291 

291 

292 

2g3 

293 

294 

295 

2q5 

296 

297 

298 

298 

299 

3oo 

332 

333 

334 

334 

335 

336 

337 

338 

338 

339 

340 

341 

342 

342 

374 

374 

375 

376 

377 

378 

379 

38o 

38i 

382 

383 

383 

384 

385 

TABLE  II.  —  To  fiiul  the  time  T\  the  sum  of  the  radii  i-j^  r",  nnil  tlie  choid  <■  being  given. 


Sum  ul'  thi!  Uuilll 


r  -f-  r  ". 


Chord 
C 


0,00 

0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,06 

0,0-7 

0,08 
0,09 

0,10 
0,11 
0,12 
o,i3 
o,i4 

o,i5 
0,16 
o,n 
0,18 
0,1  g 

0,20 
0,21 
0,2? 
0,23 
0,24 

0,25 

0,26 
0,27 
0,28 
0,29 

o,3o 
o,3i 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
Oj4i 
0.42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
o,85 
o,go 
0,95 
1,00 


2,17 


Days  |dit' 


0,000 
0,428 

o,856 

1,284 

i,7i3 

2,i4i 
2,569 

2.997 
3,425 
3,853 

4,281 

4,7«» 
5,i3" 
5,565 
5,993 

6.421 

6,849 

7,2 

7,-'>5 

8,i33 

8,56o 
8,988 
9,416 
9,843 


10,698 
11,126 
11,553 
1 1 ,980 

I2,4o8 

12,835 
13,262 
13,689 
i4,ii6 
14,543 

1 4,9 
15,396 
1 5,823 
i6,25o 
16,676 

17,102 
17,529 
17,955 
i8,38i 
18,807 

19,233 
2i,36i 
23,486 
25,607 
27,725 
29,839 


3 1,949 
34,o55 
36,1 55 
38,25o 
40,339 
42,422 


21 
21 

23 

24 

25 
25 

27 
28 
28 

3o 
3i 

32 

33 
33 

34 
36 
37 
37 
3g 

40 
4f 
42 
43 

Ai 
49 
54 
60 
65 
70 


2,18 


Udys  jdif. 


0,000 
0,42g 
o,858 
1,287 
1,717 

2,146 
3,575 
3,004 
3,433 
3,862 

4,2gi 
4,720 

5,149 
5,578 
6,007 

6,436 
6,865 
7,294 
7,723 
8,i5i 


8,58o    20 
9,009 
9,437 
9,866 
lo,2g5 


2,19 


Unys  jdir. 


0,000 
o,43o 
o,86<; 
1,291 


2,3545 


10,723 

ii,i5i 
ii,58o 
1 2 .008 
12,436 

12,865 
13,293 
1 3,721 
14,149 
14,576 

1 5,oo4 
i5,432 
1 5,860 
16,2: 
16, -"iS 

£7, 142 
17,569 
17,997 
18,424 

i8,85i 
19,277 

2I,4lO 
23,540 
25,667 
27,790 
29,909 


32,024 

34,i35 
36, 240 
38,34o 
40,435 

2,523 


60 

65 

70 

75 
80 
86 
91 
96 
loi 


2,3762 


2,l5l 

2,58i 
3,011 
3,44 1 
3,871 

4,3oi 
4,73i 
5,161 
5,591 
6,021 

6,45 1 
6,881 
7,3 1 1 
7,74o 
8,170 

8,600 

9,029 

9,459 

9,889 

io,3i8 

10,748 
11,177 
1 1 ,606 
i2,o36 
12,465 

12,89 
i3,323 
i3,752 
i4,i8i 
i4,6io 

1 5,039 
1 5,468 
15.896 
16.325 
16,753 

17.182 
17,610 
i8,o38 
1 8,466 
18,89, 

19,322 
21,460 
23,595 
25,727 
27,855 
29,979 


2,20 


Uuys  |ilil'. 


32,099 
34,21 5 
36,326 
38,43 1 
4o,53i 
42,6241 


24 

24 
26 

27 
27 
28 

3o 
3i 

32 

33 
33 

34 
3 

37 
3 

39 

39 

4' 

4i 

42 

43 

44 
49 
54 
59 
64 
70 


75 
80 
85 
90 
95 
101 


2,3981 


0,000 
0.431 
0,862 
1,293 
1,724 

2 , 1 56 
2.587 
3,oi« 
3,449 
3,880 

4,3 1 1 
4,742 
5,173 
5,604 
6,o35 

6,466 
6,896 

7,327 
7,758 
8,189 

8,6.9 

9,050 

9,481 
9.91  r 
10,343 

10,773 

II,2o3 

1 1 ,633 
i2,o63 
12,493 

12,924 
i3,354 
13,784 
i4,2i4 
14,643 

1 5,073 
i5.5o3 
15,933 
16,362 

16,792 

17,221 
i7,65o 
i8,0"9 
i8,5o8 
18.937 

19,366 
21,509 
23,64g 
25,786 

27,919 
3o,o4g 


2,21 


lluya  |dir. 


0,000 
0,433 
0,864 
1,296 
1,728 

3, 160 

2,5g3 
3,035 
3,457 
3, 

4,331 

4,753 
5,i85 
5,617 
6,048 

6,480 
6,g  1 2 

7,344 
7,776 
8,207 

8,639 
9,071 
9,5o2 
9-0  34 
23  10, 365 


32,174 
34,295 
36,4 1 1 
38,521 
40,626 


2,22 


Uuys  |dir. 


10,797 
11,228 
11,659 
i2,ogi 
12,522 

I2,g53 
i3,384 
i3,8i5 
14,246 
14,677 

i5,io8 
i5,538 
15.969 
l6.3gg 
i6,83o 


39  17,260 
17,691 
18,121 
i8,55i 
18,981 


19,411 
3  7,558 
33,7o3 
25,845 
37.984 
3o,ii8 

33,248 
34,37 
36,4g5 
38,6ii 
40,733 
3,826 


II 

13 

i4 

i5 
16 
16 
17 
19 

30 
20 
22 
22 
24 

34 

36 

27 
27 
28 

29 

3o 
3i 

32 


33 

34 
36 
36 
38 

38 

39 
4o 
4i 
43 
43 

5o 
55 

59 
64 
69 

75 
80 


2,735|lOll 

2,4200'|  2,4421 


0,000 
0,433 
0,866 

1,299 
1,733 

2, 1 65 

=.598 
3,o3i 
3,464 
3,897 

4,33o 
4,763 
5,ig6 
5,629 
6,062 

6,495 
6,928 
7,36o 
7,793 
8,226 

8,659 
9,091 
9,53. 
9>956 
I  o,38g 

10,82 
11,254 
11,686 
12,1 1 
i2,55o 

12,982 
i3,4i4 
1 3,846 
14,278 
i4,7>o 

i5,i42 

1 5,574 
1 6,00  5 
16,437 
16,868 

17,29g 
17,731 
18,162 
i8,5g3 
19,024 


19,455 
2 1 ,608 
23,758 
25,904 
28.048 
30^187 

32,323 
34,454 
36,58o 
38,701 
40,817 
43,926 


12 
i3 
I 

i5 
i5 

17 
lb 
I 

19 

31 
21 
23 
23 

25 
25 

36 
27 
29 

3o 
3i 

33 

33 
33 

34 
35 
36 

37 
38 

4o 
4o 
4i 
42 
43 


0,0000 
0,000 1 
0,0004 
0,0009 
0,0016 

0,0035 
o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,01 3 1 
0,0144 
0,0169 
0,0196 

0,0225 
o,o356 
0,0289 
0,0324 
o,o36i 

o,o4oo 
0,044 1 
0,0484 
o,o52g 
0,0576 

0,0625 
0,0676 
0,0739 
0,0784 
0,084 1 

o,ogoo 
0,0961 
0,1034 
0,1089 
o,  1 1 56 

0,1225 
0,1296 
0,1369 
o,i444 

0,l52I 

0,1600 
0,1681 
0,1764 
o,i84g 
0,1936 


4A  0,2035 
4o  o,35oo 
o,3o3  5 
o,36oo 
0,4225 
0,4900 


69 

74 
79 
84 

95 
101 


0,5625 
0,6400 
0,7335 
0,8100 
0,9025 
1 ,0000 


2,46421  ê 


Î  .  (r  -f-  r"  )^  or  r^  4"  ' 


nearly. 


426 
43 

85 

128 
170 

2l3 

256 
298 
341 
383 


427 

43 
85 

138 

171 

2l4 

256 

299 

342 
384 


428 

43 

86 

128 

171 

2l4 

357 
3oo 
342 
385 


439 

43 

86 

129 

173 

2l5 

257 
3oo 
343 
386 


43o 

43 1 

432 

433 

43 

43 

43 

43 

86 

86 

86 

87 

129 

129 

i3o 

i3o 

173 

172 

173 

173 

2l5 

216 

216 

217 

258 

359 

25q 

260 

3oi 

3o2 

,302 

3o3 

344 

345 

346 

346 

387 

388 

38q 

3qo 

43 
87 
i3o 
174 
217 
260 
3o4 
347 
3qi 


Pro|i.  parts  (or  llic  sum  of  llie  Radii. 
■  I  2   I  3|  41   5|  6|  7|8|9 


i3 
i4 

i5 
16 

17 
18 

'9 

30 
21 
22 

23 

24 

25 

26 
27 
28 

29 

3o 
3i 

32 

33 
34 

35 
36 

37 
38 

39 

4o 
4i 
A-> 
A3 

A4 

45 
46 
47 
48 

49 

5o 
5i 

52 

53 
54 

55 
56 

57 
58 

59 

60 
61 
63 

6: 


8  10 
II 
9 
9 


8  10 
8  10 
8 


'9 
19 
20 
17  20 


i4  18 
18 

19 


1 5  20 

i5 

16 

16 

16 


27  33 


38 
28 
29 

129 
3o 
3o 
3i 


38 

32 

36 

40 


23 
23 
24 

25 
2  5 
36 

27 
27 

38 
29 
29 

3o 
3i 

32 
32 

33 
34 
34 

35 
36 
36 

37 
38 


13 

i3 

i4 
i4 
i5 
16 
17 


20 
21 
22 

23 
23 

24 

25 

26 

27 
28 
29 

3o 
3i 

32 
32 

33 
3A 
35 

36 

37 
38 

39 
4o 


33  3g 


39  46 
46 

47 


4i 

I 

42 

A3 

39  AA 


45 
46 
47 
48 

49 

5o 
5o 
5i 

52 

53 

54 
55 
56 
57 
58 

59 
59 
60 
61 
62 

63 
72 
81 
90 


TABLE  II.  —  To  find  the  time  T\  the  sum  of  the  radii  r  -\-r'\  and  the  chord  c  being  given. 


Sum  of  the  Radii  r-\-r". 


Chord 
C. 


0,00 
0,01 

0,02 
o,o3 
0,04 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
0,1 3 
o,i4 

o,i5 

0,16 

0,17 

,18 

.19 

0,20 
0,21 
0,22 

0,23 

0,24 

0,25 

0,26 
0,27 

0,28 
0,29 

o,3o 
o,3i 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 
1,00 


2,23 


Days  |dif. 


0,000 
0,434 
0,868 

I,302 

1,736 

2,170 
2,604 
3,o38 
3,472 
3,906 

4,340 

4,774 

5,208 
5,642 

6,076 

6,5io 
6,943 

7.377 
7,811 
8,244 

8,678 
9,112 
9,545 
9'979 

IO,4l2 

10,846 
11,279 
11,712 
12,145 
13,579 

l3,OI2 

1 3,445 
13,878 

i4,3ii 
14,743 

15,176 
15,609 
1 6,04 1 
16,474 
16,906 

17,339 

17,771 
18,2 
1 8, 63  5 
19,067 

19,499 
21,637 

23,8l2 

25,963 

28,1  12 

3o,256 

32,397 
34,533 
36,664 
38,791 
40,912 
43,027 


2,24 


Days  Idif. 


o,Ouo 
0,435 
0,870 
i,3o5 
1, 740 

3,175 
2,610 
3,045 
3,480 
3,9i5 

4,35o 
4,785 
5,220 
5,655 
6,089 

6,524 
6,959 
7,394 
7,828 
8,263 

8,698 
9,i32 
9,567 
10,001 
10,436 

10,870 
1 1 ,3o4 
1 1 ,738 
12,173 
12,607 


i3,o4i 
1 3,475 
13,909 
32  14,343 
34   1 4,777 


2,25 


Days  |dir. 


0,000 

o,436 
0,872 
i,3o8 
1,744 

2,1 

2,616 

3,o52 

3,488 

3,924 

4,36o 

4,795 
5,23i 
5,667 
6,ro3 

6,539 
6,974 
7,4 10 
7,846 
8,281 

8,717 
9, 1 53 
9,588 
10,023 
10,459 

io,f 

11,329 

11,765 

12,200 

12,635 


29  13,070    29 

30  i3,5o5    3o 


2,26 


Days  |(lir. 


34 
35 

36 

37 
38 

39 
4<- 
4i 
42 
43 

49 
53 

59 
64 
69 

74 
79 
85 
89 
94 
99 


2,4865 


l5,2IO 

1 5,644 
16,077 
i6,5ii 
16.944 

17,378 
17,811 
18,244 
18,677 
19,110 

19,543 
2 1 ,706 
23,865 
26,022 
28,176 
3o,325 

32,471 
34,612 
36,749 

38  ,r- 
4 1, 006 
43,126 


1 3,. 

14,375 

i4,8io 

1 5,244 
15,679 
i6,ii3 
16,548 
16,982 

17,417 
17,85 1 


42  18,719 

43  19,153 


2,5088 


0,000 
0,437 
0,874 
1,3  II 

1,748 

2,i85 
2 ,62  2 
3,059 
3,496 
3,932 

4,369 
4,806 
5,243 
5,680 
6,116 

6,553 
6,990 

7,427 
7,863 
8,3oo 

8,736 
9,173 
9,609 
10,046 
10,482 

10,918 
11,355 
11,791 
12,227 
12,663 

13,099 
i3,535 
'3,971 
14,407 
14,843 

15,278 
i5,7i4 
16,149 
1 6,585 
17,020 


2,27 


Days  \A\\\ 


0,000 
o,438 
0.876 
i,3i4 
1,752 

2,190 
2,627 
3,o65 
3,5o3 
3,941 

4,379 
4,817 
5,254 
5,692 
6,i3o 

6,568 

7.oo5 
7,443 
7,88 
8,3i 

8,756 
9,193 
9,63 1 
10,068 
io,5o5 


38  17,455 
4o  17 


19,587 
21,754 
23,919 

26,or 

28,239 

30,394 

32,545 
34,691 

36,833 
38,969 
4i,ioi 
43,226 


10,943 
ii,38o 

11,817 

12,254 
28  12,691 


18,326 
18,761 
'9,196 

!9,63o 
21 ,8o3 
23,973 
26,140 
28,3o3 
3o,463 

32,618 
34,770 
36,917 
39,o58 
41,195 
43,325 


2,28 


Days|dir. 


2,5313  I  2,5538 


i3,i28 
1 3,565 
14,002 
14,439 
14,876 

i5,3i2 

1 5,749 
i6,i85 
16,622 
i7,o58 

17,494 
17,930 
I 8, 366 
18,802 
19,238 

19,674 

21,852 

24,026 
26,198 
28,366 
3o,53i 

32,692 

34,848 

37,000 

39,147 

4i,  " 

43,425 


0,000 
0,439 
0,878 
i,3i7 
1,756 

2,194 
2,633 
3,072 
3,5ii 
3,950 

4,389 
4,827 
5,266 
5,7o5 
6,i43 

6,582 
7,021 
7,459 
7,898 
8,337 

8,775 
9,21 3 
9,652 
10,090 
10,528 

10,967 
ii,4o5 
1 1 ,843 
12,281 
12,719 

i3,i57 
13,595 
i4,o33 

14,471 
14.908 

1 5,346 
15,784 
16,221 
i6,658 
17,096 

17,533 
17,970 
18,407 
18,844 
19,281 

19,71 
2 1 ,900 
34,080 
26,256 
28,430 
68  30,599 


2,5765 


2,29 


Day..;  |dir. 


32,765 
34,927 
37,084 
39,236 
41,382 


0,000 
0,440 
0,880 
1,320 
1,759 

2,199 
2,639 

3,079 
3,519 

3,958 

4,398 
4,838 
5,278 

5,717 
6,1 57 

6,597 
7,o36 
7,476 
7.915 
8,355 


8,794 
9,234 
9,673 

10,1  12 
10,552 


10,991 

1 1 ,4  3o 

!  1 ,869 

i2,3oa 

12,747 

i3,i86 
1 3,625 
14,064 
i4,5o2 
14,941 

i5.38o 
i5,8i8 
16,257 
16,695 
I7,i33 

17,572 
18,010 
18.448 
18,886 
19,32" 

19,761 
21,948 
24, 1 33 
26,3 1 5 
28,493 
3o,668 


2,30 


Days  |dif. 


43,523   99 
2,5992 


73  32.838 
78  35,oo5 
37,167 
39,324 
41,476 
43,622 


83 


94 


23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 

33 

33 
35 
35 
37 
38 

38 

39 
40 

4i 
43 

Aà 
49 
53 
58 
63 
67 

73 
78 
83 
88 
93 
99 


0,000 
0,44 1 
0,882 

1,322 
1,763 

2,304 

2,645 
3,086 
3,526 
3,967 

4,408 
4  ' 
5,289 
5,73o 
6,170 

6,611 
7,o52 
7,492 
7.933 
8,373 

8,81 3 
9,254 
9,694 
1 0,1 34 
10,575 

11. 01 5 
11,455 
ii,8q5 
12,335 

12,775 

i3,3i5 
i3,655 
14,095 
i4,53' 
14,974 

i5,4i3 
1 5,853 
16,292 
16,732 
17,17' 

17,610 
18,049 
18,488 
18,927 
19,366 

19,805 

21,997 
24,186 
26,373 
28,556 
30,735 

32.911 
35,oB3 
37,25o 
39,412 
41,569 
43,721 


2,31 


Days  |dir. 


0,000 
0,442 
0,884 
1,325 
1,767 

2,209 
2,65i 
3,092 
3,534 
3,976 

4,417 
4,859 
5,3oi 
5,742 
6,1 

6,625 
7,067 
7,5o8 
7,950 
8,391 

8,833 
9,274 
9,715 
10, 1 56 
io,5g8 

1 1 ,039 
1 1 ,480 
1 1 ,92 1 
1 2 ,362 
i2,8o3 

1 3,244 
1 3,684 
i4,i25 
1 4,566 
1 5,007 


1 5,447 
15,887 
16,328 
16,768 
37  17,208 


2,6221 


2,32 


Days  |dTl'. 


0,000 
0,443 

0,885 
1,328 

1.771 

2,2l4 

2,656 
3,099 
3,542 
3,984 

4,427 
4,869 
5,3t2 
5,755 
6,197 

6,640 
7,083 
7.525 
7,967 
8,409 

8,852 

9,294 
9,736 
10,178 
10,621 


ii,o63    24 
ii,5o5 
1 1 ,947 
12,389 
12,83 1 


17,648 
18,089 
18,529 
18,968 
19,408 

19,848 
22,045 
24,239 
26,431 
28,619 
3o,8o3 

32,984 
35,161 
37,333 
39,500 
41,662 
98143,819 


3o 
3i 

32 
32 

34 
35 
35 

37 
38 

39 
39 
4o 
42 
42 

43 
48 
53 

57 
62 
68 

73 

77 


93 


2,6450  I  2,6681 


13,272 
1 3,7 1 
i4,i56 
14,598 
1 5,039 

1 5,48 1 
15,922 
i6,363 
i6,8o5 
17,246 

1 7,687 

18,12. 

18,569 

19,010 

19,450 

19,891 
22,093 
24,292 

26„"" 

28,681 
30,871 

33,o57 
35,238 
37,41 5 
39,588 
41,755 
43,917 


0,0000 
0,0001 
o,ooo4 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,0121 
0,01 44 
0,01 69 
0,0196 

0,0225 
0,02  56 
0,0289 
o,o324 
o,o36 1 

o,o4oo 
0,044 1 
o,o484 
0,0529 
0,0576 


0,0625 
0,0676 
0,0729 

26  0,0784 

27  o,o84i 


0,0900 
0,0961 
0,1024 
0,1089 
0,1 1 56 

0,1225 
0,1 296 
0,1 36g 
0,1 444 
0,1 521 

o,  1 600 
0,1681 
0,1764 
0,1849 
0,1936 


^    0,2025 

o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 


2,6912 


0,5625 
0,6400 
0,7225 
0,8100 
0,9025 
1 ,0000 


(r 


è  .(r  +  r")^     or    r' 


nearly. 


432 

433 

434 

435 

436 

437 

438 

439 

440 

44 1 

■  442 

43 

43 

43 

M 

ÂA 

AA 

AA 

AA 

AA 

AA 

AA 

86 

87 

87 

87 

87 

87 

88 

88 

88 

88 

88 

i3o 

i3o 

i3o 

i3i 

i3i 

i3i 

i3i 

l32 

l32 

l32 

i33 

173 

173 

174 

174 

174 

175 

175 

176 

176 

176 

177 

216 

217 

217 

218 

218 

219 

219 

220 

220 

221 

221 

sSg 

260 

260 

261 

262 

262 

263 

263 

264 

265 

265 

302 

3o3 

3o4 

3o5 

3o5 

3o6 

307 

3o7 

3o8 

309 

3°9 

346 

346 

347 

348 

349 

35o 

35o 

35i 

352 

353 

354 

389 

390 

391 

392 

392 

393 

394 

395 

396 

397 

398 

443 


AA 

I 

80 

2 

1 33 

3 

"77 

4 

222 

5 

266 

6 

3io 

7 

354 

8 

399 

9 

TABLE    II.  —  To  fin  il  the  time  T:  the  sum  of  the  iDtlii  r-|-r '',  and  the  chord  c  boinp;  given. 


Srum  of  iho  Kailii  t-\-t" 


Choiri 
C. 

2,33 

2,34 

2,35 

Days  lilif. 

lliijs  lilif. 

Ilujs  |ilil. 

0,00 

0,000 

0,000 

0,000 

0,0 1 

0,444 

1 

0,445 

1 

0,446 

I 

0,02 

0,887 

2 

0.889 

3 

0,891 

2 

o»o3 

1, 33 1 

3 

1.334 

3 

1,337 

3 

o,o4 

1  {ll'i 

4 

1,779 

3 

1,783 

4 

o,o5 

2,318 

5 

2,333 

5 

2,228 

5 

0,06 

2,662 

6 

2,668 

5 

2.673 

6 

0,07 

3,106 

6 

3.113 

- 

3,119 

-J 

0,08 

3,54q 

8 

3.557 

- 

3,564 

8 

o,og 

3,593 

8 

4,001 

9 

4, OK) 

8 

0,10 

4,436 

10 

4.446 

Q 

4,455 

10 

0,1  I 

4,880 

10 

4.8Q0 

II 

4,901 

10 

0,12 

5.324 

1 1 

5.335 

1 1 

5,346 

12 

0,1 3 

5.-6- 

13 

5,~c) 

i3 

5,792 

13 

0,1 4 

6,211 

i3 

6,224 

i3 

6,33-7 

i3 

o,.5 

6.654 

i4 

6,668 

i5 

6,683 

i4 

0,16 

-.09- 

lO 

7,ii3 

i5 

7.128 

i5 

0,17 

-,54i 

16 

7.557 

16 

7,573 

16 

0,18 

7,984 

I- 

8,001 

17 

8,018 

17 

0,1  g 

8,427 

•9 

8,446 

18 

8,464 

18 

0,20 

8.871 

19 

8,890 

iq 

8,90g 

iq 

0,2 1 

9.314 

2(. 

9,334 

30 

9,354 

30 

0,22 

9'757 

31 

9:778 

31 

9>7S9 

31 

0.23 

10.200 

22 

10,222 

32 

10,344 

33 

0,34 

10,644 

22 

10,666 

23 

10,689 

23 

0,25 

11.087 

23 

1 1,110 

34 

ii,i34 

24 

0,26 

ii.53o 

24 

11,554 

25 

11.570 

25 

0,27 

1 1 ,973 

25 

1 1 .998 

26 

12.034 

2b 

0,28 

i2.4i5 

27 

13.443 

27 

13,469 

26 

0,2g 

12,858 

2b 

12,886 

37 

12,913 

38 

o,3o 

i3,3oi 

29 

i3,33o 

38 

i3,358 

3q 

0,3 1 

1 3,744 

29 

i3,773 

3o 

i3.8o3 

3Q 

0,32 

i4,i£6 

Jl 

14-317 

3o 

14,247 

3i 

0,33 

14,629 

32 

1 4,661 

3 1 

14.692 

3i 

0,34 

15,072 

33 

i5,io4 

32 

i5,i36 

33 

0,35 

i5,5i4 

33 

1 5,547 

34 

z5,58i 

33 

o,36 

15.956 

35 

15,991 

34 

16,025 

M 

0,37 

16,399 

35 

16,434 

35 

16,469 

35 

o,38 

16.841 

36 

16,877 

36 

16,913 

36 

0,39 

17,283 

37 

17,330 

37 

17,357 

37 

o,4o 

17,725 

38 

i-',763 

38 

17,801 

38 

0,4 1 

18,167 

3g 

18.306 

3q 

18,345 

3q 

0,42 

18,609 

4o 

i8,64q 

40 

18,689 

40 

0,43 

1 9,o5 1 

4i 

19,093 

4i 

19,133 

41 

oM 

19,493 

42 

19,535 

42 

19,577 

4i 

0,45 

19,934 

43 

I9'977 

43 

20,020 

43 

o,5o 

22.l4l 

48 

22,189 

47 

22,236 

48 

0.55 

24,345 

53 

24,398 

53 

24,45o 

53 

0,60 

26,546 

58 

26,604 

57 

36,661 

57 

o,65 

28,744 

63 

28.806 

63 

38,869 

63 

0,70 

3o,938 

68 

3 1, 006 

67 

31,073 

67 

0,75 

33,129 

72 

33,201 

73 

33,374 

72 

0,80 

35,3i6 

77 

35.393 

77 

35,470 

77 

o,85 

37.498 

83 

37,580 

83 

37,662 

83 

0,90 

39,675 

88 

3q,763 

«7 

39,85o 

87 

0,95 

4 1, 848 

92 

41,940 

93 

42,o32 

92 

1,00 

44,014 

98 

44,112 

97 

44,309 

97 

2,71 

45 

2,73 

78 

2,76 

13 

2,36 


0,000 
0,447 

o,8g3 
1, 340 
1,786 

2,233 

2 ,67q 
3,126 
3,572 
4,018 

4,465 
4,911 
5.358 
5,804 
6,2  5o 

6,697 
7,143 
7,58g 
8,o35 
8,482 

8,928 
9,374 
9.820 
0,266 
0,712 

1, 1 58 
1,604 
2  ,o5o 
2,495 
2,941 

3,387 
3.832 
4,278 
4,723 
5,169 

5,614 
6,059 
6,5o4 
6,949 
7,394 

7,839 
8,284 
8,729 
9,174 
9,618 

20,063 
22,284 
24.5o3 
26,718 
38,931 
3i,i4o 

33,346 
35,547 
37,744 
39,937 
43,124 
44,3o6 


2,7848 


2,37 


Days  lilif. 


0,000 
0,447 
0,895 
1,342 
1,790 

2,237 

2,685 
3.i32 
3,58o 
4,027 

4,474 
4.933 
5.36q 
5.816 
6,364 

6,711 
7,i58 
7,6o5 
8,o53 
8,5oo 

8,947 
9,394 
9,84 1 
0.288 
0^735 

1. 183 
1^638 
3,075 

2,523 
2,968 

3.41:) 
3,862 

4.3o8 

4,754 

5,301 

5,647 
6,093 
6.539 
6,985 
7,43 1 

7,877 
8,333 
8,76g 
9,3i5 
9,660 

30,106 

3  2.332 
34,555 
26,776 

38,gg3 
3 1, 207 

33,417 

35.634 

37,836 

40,02 

42.216 

44 .4o3 


2,8085 


2,38 


ll«)s  lilif. 


t,,ooo 

0,448 

o,8g7 
1,345 
i>794 

2,242 
2,690 
3, 1 39 
3.587 
4,o35 

4,484 
4,932 
5,38o 
5,839 
6,277 

6,725 
7,173 
7,621 
8,069 
8,5i8 

8,966 
9,4i4 
9,862 
o,3c9 
0,757 

r,3o5 
1,653 
3,101 
2.548 
2-996 

3,443 
3,891 
4,338 
4,786 
5,233 

5,680 
6,127 
6,574 
7,021 
7,468 

7,9i5 
8,362 
8,809 
9,355 
9,702 

20, 1 48 
2  2,379 
24,607 
36,833 
39.055 
31,374 

33,489 
35,700 
37,907 
40,110 
43,307 
44 .500 


2,8322 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 
,oo36 
,oo4g 
,0064 
,0081 


,0100 
,0121 
,0144 
,01 6g 
,0196 

,0235 
,02  56 
,028g 
,o324 
,o36i 

,o4oo 
,044 1 
i0484 
io53g 
,0576 

,0625 
,0676 
,0729 
,0784 
.084 1 

,ogoo 
,0961 
1034 
1089 
ii56 

1225 
1296 
1369 
1444 
l52I 

1600 

168 1 
1764 

i84g 
ig3Ô 

2025 
25oo 
3o25 
,3600 
4225 
i4goo 

625 
,64oo 
7235 
,8100 
9035 
,0000 


K    .  (,r  -\-  r"  )  ^    or  r^  -j-  r'  ^  n  -iirly. 


441 

443 

443 

AM 

445 

446 

447 

448 

449 

iA 

44 

44 

44 

45 

45 

45 

45 

45 

88 

88 

8q 

89 

8q 

89 

8q 

90 

90 

l32 

1 33 

1 33 

i33 

i34 

1 34 

1 34 

i34 

i35 

176 

177 

177 

178 

178 

178 

179 

179 

180 

221 

331 

222 

222 

223 

223 

224 

234 

225 

265 

265 

266 

266 

367 

268 

268 

269 

269 

309 

309 

3io 

3ii 

3l2 

3l2 

3i3 

3i4 

3i4 

353 

354 

354 

355 

356 

357 

358 

358 

359 

397 

398 

399 

400 

40 1 

4oi 

4o2 

4o3 

4o4 

Prop. 

parts  fur  ttif,  8UII1  uf  tho  Radii.  1 

■  1 

2l3|4|5|6|7|8|9  1 

1 

0 

0 

0 

0 

1 

I 

I 

1 

I 

2 

0 

0 

1 

I 

1 

1 

1 

3 

2 

3 

0 

I 

1 

I 

3 

2 

3 

3 

3 

4 

0 

I 

1 

2 

3 

2 

3 

3 

4 

5 

I 

3 

2 

3 

3 

4 

4 

5 

6 

1 

3 

2 

3 

4 

4 

5 

5 

7 

I 

2 

3 

4 

4 

5 

6 

fi 

8 

3 

3 

3 

4 

5 

6 

6 

7 

9 

2 

3 

4 

5 

5 

6 

n 

8 

10 

3 

3 

4 

5 

6 

-T 

8 

q 

1 1 

2 

3 

4 

6 

7 

8 

q 

10 

12 

2 

4 

5 

6 

7 

8 

10 

1 1 

i3 

3 

4 

5 

7 

8 

q 

10 

12 

14 

3 

4 

6 

7 

8 

10 

1 1 

i3 

i5 

2 

3 

5 

6 

8 

q 

1 1 

12 

i4 

16 

2 

3 

5 

6 

8 

10 

1 1 

i3 

i4 

17 

2 

3 

5 

7 

q 

10 

12 

14 

i5 

18 

2 

4 

5 

7 

9 

1 1 

i3 

i4 

16 

'9 

2 

4 

6 

8 

10 

1 1 

i3 

i5 

17 

20 

2 

4 

6 

8 

10 

12 

i4 

16 

18 

21 

2 

4 

6 

8 

1 1 

i3 

i5 

17 

iq 

22 

2 

4 

7 

q 

1 1 

i3 

i5 

18 

20 

23 

2 

5 

7 

q 

12 

■  4 

16 

18 

21 

24 

2 

b 

7 

10 

12 

i4 

17 

■9 

22 

25 

3 

5 

8 

10 

i3 

i5 

18 

30 

23 

26 

3 

5 

8 

10 

i3 

16 

18 

21 

23 

27 

3 

5 

8 

1 1 

i4 

16 

iq 

22 

24 

28 

3 

6 

8 

1 1 

i4 

17 

2t 

23 

35 

29 

3 

6 

9 

13 

i5 

17 

20 

23 

26 

3o 

3 

6 

q 

12 

i5 

18 

21 

24 

27 

3i 

3 

6 

q 

12 

16 

iq 

22 

35 

28 

32 

3 

6 

10 

l3 

16 

iq 

32 

26 

29 

■Ji 

3 

7 

10 

l3 

17 

20 

23 

36 

3o 

M 

3 

7 

10 

14 

17 

20 

24 

27 

3i 

35 

4 

7 

I  I 

i4 

18 

21 

25 

28 

32 

36 

4 

7 

I  1 

14 

18 

22 

25 

2q 

32 

37 

4 

7 

1  1 

i5 

iq 

22 

26 

3o 

33 

38 

4 

8 

I  1 

i5 

iq 

33 

37 

3o 

34 

39 

4 

8 

12 

16 

20 

23 

27 

3i 

35 

40 

4 

8 

12 

16 

20 

24 

38 

32 

36 

4i 

4 

8 

12 

16 

21 

25 

20 

a 

37 

42 

4 

8 

1 3 

17 

21 

25 

2q 

M 

38 

4<i 

4 

9 

i3 

17 

22 

26 

3c 

M 

3q 

44 

4 

9 

i3 

18 

22 

26 

3i 

35 

40 

45 

5 

q 

i4 

18 

23 

27 

33 

36 

4i 

46 

5 

9 

14 

18 

33 

28 

32 

37 

4i 

47 

5 

q 

i4 

iq 

24 

28 

Si 

38 

43 

48 

5 

10 

14 

iq 

24 

2q 

M 

38 

4i 

49 

5 

10 

i5 

2Ù 

25 

29 

M 

39 

44 

5o 

5 

10 

i5 

30 

25 

3o 

35 

4o 

45 

5i 

5 

10 

i5 

20 

26 

3i 

36 

4i 

46 

53 

5 

10 

16 

21 

26 

3i 

36 

42 

47 

53 

5 

1 1 

16 

21 

27 

32 

37 

42 

48 

54 

5 

1 1 

16 

22 

27 

32 

38 

4i 

49 

55 

6 

1  1 

17 

32 

38 

33 

3q 

44 

5o 

56 

6 

1 1 

17 

22 

38 

34 

3q 

45 

5o 

57 

6 

1 1 

17 

33 

3q 

34 

4o 

46 

5i 

58 

6 

12 

17 

23 

2q 

35 

4i 

46 

52 

59 

6 

12 

18 

24 

3o 

35 

4i 

47 

53 

60 

6 

I  2 

18 

34 

3o 

36 

43 

48 

54 

61 

6 

12 

18 

24 

3i 

37 

43 

4q 

55 

62 

6 

12 

iq 

25 

3i 

37 

43 

5o 

56 

63 

6 

i3 

iq 

25 

32 

38 

44 

5o 

57 

64 

6 

i3 

'9 

26 

32 

38 

45 

5i 

58 

65 

7 

i3 

20 

36 

33 

3q 

46 

53 

5q 

fi6 

7 

i3 

20 

26 

33 

40 

46 

53 

5q 

67 

7 

i3 

20 

37 

34 

4o 

47 

54 

60 

68 

7 

i4 

20 

27 

34 

4i 

48 

54 

61 

69 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

70 

7 

i4 

21 

38 

35 

43 

4u 

56 

63 

80 

8 

16 

24 

33 

40 

48 

5C 

64 

72 

90 

0 

18 

37 

36 

45 

54 

63 

72 

81 

ion 

1  r 

3f 

3c 

40 

5f 

6f 

70 

80 

90 

AlO 


TABLE  II 

.  —  To  find  the  time  T";  the  sum 

of  the  radii 

r  +  r" 

and  the  chord 

c  being 

given. 

tjum  of  tlie  Radii  r  -\-  r".                                                                                                            1 

Chord 
C. 

2,39 

Uajs  lilif. 

2,40 

Days  |(lir. 

2,41 

2,42 

2,43 

Days  |dif. 

2,44 

Days  |dif. 

2,45 

2,46 

2,47 

2,48 

Days  |dir. 

Days  |dif. 

Days  |dif. 

Days  l.iif. 

Days  |dif. 

Days  |dlf. 

0,00 

0,0 1 

O,03 

o,o3 
o,o4 

0,000 
0,449 
0,899 
1,348 
1.797 

I 
2 

3 
4 

0,000 

o,45o 

0,901 
1, 35 1 
1,801 

I 
I 
3 
4 

0,000 

o,45i 

0,902 
1,354 

i,8o5 

I 
2 
2 
4 

0,000 
0,452 
0,904 
1,356 
1,809 

I 
3 

3 
3 

0,000 
0,453 
0,906 
1,359 
1,812 

I 
2 

3 
4 

0,000 
0,454 
0,908 
1,362 
1,816 

I 
3 
3 
4 

0,000 
0,455 
0,910 
1,365 
1,820 

1 

2 

3 
4 

0,000 

o,456 

0,912 
1,368 

1.824 

I 

2 
3 

0,000 
0,457 
0,914 
1,370 
1,827 

I 
I 
3 
4 

0,000 

o,458 

0,915 
1,373 

1, 83 1 

I 
3 

3 
4 

0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

o,o5 
0,06 
0,07 
0,08 
0,09 

2,247 
2,696 
3,145 
3,595 
4,044 

4 
6 

7 
7 
8 

2,25l 
2,702 

3,i52 
3,602 
4,o52 

5 
5 
6 
8 
y 

2,256 

2.707 
3,1 58 
3,6ir 
4,061 

5 
6 

7 
7 
8 

2,361 
2.7i3 
3,i65 
3.617 
4,o6g 

4 
6 

7 
8 

9 

2,265 

2.719 
3,172 

3,625 
4,078 

5 
5 
6 

7 
8 

2,270 
2,724 
3,178 
3.632 
4,086 

5 

e 

7 

6 
8 

2,275 
2,730 
3,i85 
3,640 
4,094 

4 
5 
6 
7 
9 

2.279 

2.735 

3.191 
3,647 
4,io3 

5 
6 

7 
7 
8 

2,284 
2, 74 1 
3,198 

3,654 
4.111 

5 
5 
6 
8 

8 

2,289 
2,746 
3,204 
3,662 
4,119 

4 
6 
6 

9 

0,0025 
0,00 36 
0,0049 
0,0064 
0,0081 

0,10 

0,1  I 

0,12 
o,i3 
o,i4 

4,493 
4.942 
5,393 
5,84i 
6,290 

10 
II 
ij 
12 
i3 

4,5o3 
4,953 
5,4o3 
5,853 
6,3o3 

9 
10 
1 1 
12 
i3 

4.5 1 2 
4,963 
5,4i4 
5,865 
6,3i6 

9 
10 
1 1 
12 
i3 

4.521 
4,973 
5,425 

5,877 
6,329 

10 
11 

13 

i3 
i3 

4,53 1 
4,984 
5,437 
5,890 
6,342 

9 
10 
II 
12 
14 

4,540 
4,9g4 
5,448 
5,903 
6,356 

9 
10 
II 
12 
i3 

4,549 
5,004 
5,45q 

5,914 
6,369 

lO 
lO 

II 

12 

i3 

4.559 
5,014 
5,470 
5,926 
6,382 

9 
II 
II 

13 

i3 

4,568 
5,025 
5,481 
5,938 
6,395 

9 
10 
11 
12 

13 

4,577 
5,o35 
5,492 
5,g5o 
6,407 

9 
10 

i3 

0,0100 
0,0121 
o,oi44 
0,0169 
0,0196 

0,1 5 
0,16 
0,17 
0,18 
0,1  g 

6,739 
7,188 
7.637 
8,086 
8,535 

i4 
i5 
16 

17 
18 

6,753 
7,2o3 
7,653 
8,io3 
8,553 

i4 
i5 
16 

17 
18 

6,767 
7,218 
7.669 
8,120 
8,57. 

i4 
i5 
16 

17 
18 

6,781 
7,233 
7,685 
8,i37 
8,589 

14 
i5 
16 

17 
18 

6,795 
7,248 
7.701 
8,i54 
8,607 

i4 
i5 
16 

17 
17 

6,809 
7,263 
7.717 
8,171 
8,624 

i4 
i5 
16 
16 
18 

6,823 
7,278 
7.733 
8,187 
8,642 

i4 
i5 
i5 

17 
i8 

6,837 
7,393 
7,748 
8,3o4 
8,660 

i4 
1 5 
16 

17 
17 

6,85 1 
7,3o8 
7.764 
8,221 
8,677 

i4 
i4 
16 
16 
18 

6,865 

7,323 

7,780 
8,237 
8,695 

14 
i5 

% 

17 

0,0225 

o,o256 
0,0289 
o,o324 
o,o36i 

0,20 
0,21 
0,22 
0,23 
0,24 

8,984 
9.433 
9,882 
io,33i 
10,780 

'9 
20 
21 
22 
22 

9,oo3 
9.453 
9,903 
10,353 
10,802 

19 
20 
21 
21 

23 

9,023 
9.473 
9.924 
10,374 
10,825 

19 
19 
20 
22 
22 

9,o4i 
9.492 
9.944 
10,396 
10,847 

18 
20 
21 
21 

23 

9.059 
9.5i2 
9.965 
10,417 
10,870 

19 
20 
30 

23 
22 

9,078 
9,532 
9,985 
10,439 
10,892 

19 
'9 
21 
21 

23 

9,"97 

9,55i 

10,006 

10,460 

10,915 

i8 

20 
20 
22 
22 

9,ii5 

9.571 
10,026 
10,482 
10,937 

'9 
'9 
21 
21 

23 

9, 1 34 

9,59" 
10,047 
io,5o3 
10,959 

18 
2r 
20 
21 

23 

9,i52 

9,610 

10,067 

10,524 

10,981 

19 
19 
20 
21 
22 

o,o4oo 
o,o44i 
o,o484 
0,0529 
0,0576 

0,25 
0,26 
0,27 
0,28 
0,29 

11,229 
1 1 ,677 
1 2 , 1 26 
12,575 
i3,o23 

23 
25 
25 

26 

27 

11,252 
11,702 
I3,l5l 
I  2 ,60  ! 

i3,o5o 

34 
24 
26 
36 
28 

1 1,276 
11.726 

12,177 
12,627 
13,078 

33 
25 
25 

27 
27 

11,299 
1 1, 75 1 
12.302 
12,654 
i3,io5 

23 

24 

25 

26 

27 

I  1,323 
11.775 
12,227 
12,680 

i3,i32 

24 
24 
25 
26 

27 

11,346 
11.799 

12,252 
12,706 

i3,i59 

23 

24 
26 
26 
27 

1 1 ,369 
11,823 
12,378 

13,733 

i3,i86 

23 
25 
25 
26 

27 

11,392 
11,848 
i2,3o3 
12.758 
i3;2i3 

33 

24 

25 

26 

27 

ii,4i5 
11,873 
12,338 
12,784 
1 3,340 

24 

25 
26 

27 

11,439 
1 1 ,896 
13,353 
12,810 
13,267 

23 

24 

25 

36 
27 

0,0625 
0,0676 
0,0729 
0,0784 
o,o84i 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

13,472 
13,920 
i4,368 
14,817 
1 5,265 

28 

3i 
3i 

32 

i3,5oo 
13,949 
14,39g 
14,848 
15,297 

28 

=9 
3o 
3i 

32 

i3,528 
13,978 
14.420 
14,87g 
i5,32g 

28 

=9 
3o 
3i 

32 

i3,556 
14,007 
14,459 
14.910 
i5,36i 

28 
39 

3o 
3i 

32 

1 3,584 
i4,o36 
14,489 
14.941 
15,393 

28 
29 

=9 
3o 
3i 

i3,6i2 
i4,o65 
i4,5i8 
14,971 
i5,424 

28 

29 
3o 
3i 

33 

i3,64o 
14,094 
i4,548 
1 5,002 
1 5,456 

28 

=9 
3o 

3i 

32 

1 3,668 
i4,i23 
14,578 
i5,o33 
1 5,488 

28 
29 

3o 
3i 
3i 

13,696 
i4,i53 
1 4,608 
1 5,064 
i5,5i9 

28 
29 

3^ 

32 

13.724 
i4,i8i 
1 4,637 
15,094 
i5,55i 

27 
38 

3o 
3i 
3i 

0,0900 
0,0961 
0,1024 
0,1089 
0,1 i56 

0,35 
o,36 
0,37 
o,38 
0,39 

i5,7i3 
16,161 
16,609 
17.057 
i7,5o5 

33 
34 
35 
36 

37 

1 5,746 
i6,ig5 
16,644 
17,093 
17,542 

33 
34 
35 
36 

37 

1 5,779 
16, 22g 
16,67g 
17,129 
17.579 

33 
34 
35 
35 
36 

i5,8i2 
16,263 
16,714 
17,164 
I7,6i5 

33 
34 
34 
36 

37 

1 5,845 
16,297 
16,748 
17,200 
17,652 

32 

33 
35 
36 
36 

15,877 
i6,33o 
16,783 
17,236 
17,688 

33 
34 
34 
35 
37 

l5.QIO 

i6;364 
16,817 

17,271 
17,735 

32 

33 
35 
35 
36 

15,942 
16,397 
i6,852 
i7,3o6 
17.761 

33 
34 
34 
36 
36 

15,975 
1 6.43 1 
16,886 
17,342 

17,797 

32 

33 
34 
35 
36 

1 6,007 
1 6,464 
16,920 
17.377 
17,833 

33 
33 
35 
35 
36 

0,1225 
0,1296 
0,1 369 
0,1 444 

0,l52I 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

17,953 
i8,4oi 
1 8,848 
19,296 
19.743 

38 
38 
4o 
4o 
43 

18^439 
18,888 
19,336 
19,785 

37 

39 
39 

4i 

4i 

18,028 

18,478 
i8,g27 

19.377 
19,826 

38 
38 
40 
4o 
43 

18,066 
[8,5i6 
■8,967 

19,417 
19,868 

37 
39 
39 
4i 
41 

i8.To3 
18,555 
19,006 
19,458 
19,909 

38 
38 
4o 
40 
4i 

i8,i4i 
18,593 
19,046 
19,498 
19,950 

37 
38 

39 
4o 
4i 

18,178 
i8,63i 
19,085 
ig,538 
19,991 

37 

39 
39 

4o 

4i 

i8.2i5 
18,670 
19,124 
19.578 

20,o33 

37 
38 

39 
40 
4i 

18,353 
18,708 
ig,i63 
ig,6i8 
20,073 

37 
38 
3q 
4o 
4i 

18.289 
18,746 
19,202 
■  9,658 
20,1 14 

37 
38 

39 
40 
40 

o,r6oo 
0,1681 
0,1764 
0,1849 
0,1936 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

20,191 
22,426 
24,659 
26,889 
29,117 
3 1, 340 

42 

48 

52 

57 
61 
67 

20,233 

22,474 

24,71 1 
26,946 
29,178 
3i,4o7 

43 

47 

52 

57 
62 
66 

20,276 

22,521 
24.763 

27,oo3 
2g,24o 
3 1, 473 

42 

47 

52 

56 
61 
66 

2o,3i8 
22,568 
24,81 5 
27,059 
29,301 
31,539 

42 

47 

52 

57 
61 
66 

2o,36o 
22,61 5 
24,867 
27,116 
39,362 
3i,6o5 

42 
46 
5i 
56 
61 
66 

20,402 
22,661 
24,918 
27,172 
29,423 
31,671 

42 

47 

52 

56 
61 
66 

20,444 
2  2 ,708 
24,970 
27,228 
39.484 
31,737 

42 

47 
5i 
57 
6i 
66 

30,486 
22,755 
25,021 
27,285 
29,545 

3i,8o3 

43 
46 
5i 
56 
61 
65 

20,528 
22,801 
25,073 
27,341 
29,606 
3 1, 868 

42 
47 
5i 
55 
60 
65 

20.570 
2  2,848 

25,123 

27,396 
29,666 

31,933 

4i 
46 
5i 
56 
61 
66 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,75 
0,80 
o,85 
0,90 
0,95 
1,00 

33,56o 

35,777 
37,989 
4o,  1 96 
42,399 
44,596 

72 
76 
81 
86 
91 
96 

33,632 
35,853 
38,070 
40,283 
42,490 
44,692 

71 
76 

8! 

86 
9' 
96 

33,7o3 
35,929 
38,i5i 
4o,368 
42,58r 
44,788 

71 
76 
81 
86 

96 

33,774 
36,oo5 
38,232 
40,454 
43,671 
44,884 

71 
76 
80 
85 

95 

33,845 
36,o8i 
38,3i2 
4o,53g 
42,762 
44  ,g79 

71 
75 
81 
86 

90 
95 

33,916 

36,1 56 
38,3g3 
40,625 
42,853 
45,074 

70 
76 
80 
85 
90 
95 

33,986 
36,232 
38,473 
40,710 
42,q42 
45,i69 

71 
75 
8o 
85 

9? 
95 

34,057 
36.307 
38,553 
40,795 
43.032 
45,264 

70 
75 
80 
85 

95 

34,127 
36,383 
38,633 
40,880 
43.122 
45,359 

70 
75 
80 
84 
89 
94 

34,197 

36,457 
38,7i3 
40,964 
43,311 
45,453 

70 
75 
79 
85 
89 
94 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 

2,8561 1 

2,8800  1 

2,9041  1 

2,9282  1 

2,9525  1 

2,9768 1 

3,0013  1  3,0258  1 

3,0505  1 

3,0752  1 

ê 

4  .  (r  +  r")=  or  r"  +  r"^  nearly.                                        | 

447 

448 

449 

45o 

45 1 

452 

453 

454 

455 

456 

457 

45 

45 

45 

45 

45 

45 

45 

45 

46 

46 

46 

89 

90 

90 

90 

go 

90 

91 

91 

91 

91 

91 

1 34 

i34 

i35 

i35 

i35 

1 36 

1 36 

1 36 

1 37 

1 37 

1 37 

179 

179 

180 

180 

180 

181 

181 

182 

182 

182 

i83 

224 

224 

225 

225 

226 

226 

237 

227 

228 

228 

239 

268 

269 

269 

270 

271 

271 

272 

272 

273 

274 

274 

3i3 

3i4 

3i4 

3i5 

3i6 

3i6 

3,7 

3i8 

3ig 

3.g 

320 

358 

358 

35g 

36o 

36 1 

362 

362 

363 

364 

365 

366 

402 

4o3 

404 

4o5 

406 

407 

4d8 

4og 

4io 

4io 

All 

458 


46 

I 

92 

2 

1 37 

3 

i83 

4 

220 

5 

275 

6 

321 

7 

366 

8 

4X2 

9 

TABLE  II.  —  To  find  the  time  T\  the  sum  of  the  radii  r-}-r  ",  and  the  chord  c  being  piven. 


tiuni  of  Iho  Kudu  r-^-r".                                                                     1 

Pro[ 

.  purl 

lor  tito 

.urn 

oltl 

e  Radii. 

■^" 

Churd 

C. 
0,00 

2,49 

^1  f^/» 

2,51 

2,52 

2,53 

llHya  |dir. 

2,54 

l)«y«  |dif. 

M2|J|4|5|b|7|Hl9 

Af^^JKJ 

1 
2 
3 

0   0 
0   0 
0   1 

0 

1 
1 

0 
I 

1 
1 

2 

1 

2 

I 

I 
2 

3 
2 

I 
2 
3 

Dnys  |dil'. 

U«)s  |dif. 

Days  |dir. 

Duys  |dir. 

0,00( 

1 

0,000 

OjOtiC 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,45c 

)  I 

0,460 

0 

0,460 

1 

0,461 

1 

0,462 

1 

o,463   I 

0,000 1 

4 

0   1 

2 

2 

3 

3 

3 

4 

0,02 

0,Q|- 

3 

0,919 

2 

0,921 

3 

0,92; 

2 

0,925 

1 

0,926  2 

0,0004 

o,o3 

i,37t 

)   c 

1,379 

2 

i,38i 

3 

1,384 

3 

1,387 

3 

1 ,390  2 

O,O0OC) 

5 

I   1 

2 

2 

3 

3 

4 

4 

5 

o,o4 

1,83; 

^ 

1,838 

4 

1,842 

4 

1,84e 

3 

1,849 

4 

1,853  4 

0,0016 

«) 

I   I 

2 

2 

3 

4 

4 

5 

5 

7 

1   1 

2 

3 

4 

4 

5 

6 

6 

o,o5 

2,2qC 

5 

2,298 

4 

2,3o3 

5 

2,307 

5 

2,3l2 

4 

2,3i6  5 

0,0025 

8 

1    2 

2 

3 

4 

5 

6 

6 

7 

0,06 

2,75:; 

5 

2,757 

( 

3,763 

5 

2,76b 

6 

2,774 

5 

2,779  6 

o,oo36 

9 

1    2 

3 

4 

5 

5 

6 

7 

8 

0,07 

3,2IC 

3,217 

f 

3,323 

7 

3,23c 

e 

3,236 

7 

3,243   6 

0,0049 

3 
3 

4 
4 
5 

r 

6 

8 

0,08 

3,66c 

3,676 

8 

3,684 

7 

3,691 

7 

3,698 

8 

3,706  7 

0,0064 

10 

' 

5 
6 
6 

7 

8 
8 

S 

0,09 

4,12e 

6 

4, 1 36 

8 

4,i44 

8 

4,i52 

e 

4,161 

8 

4,169   8 

0,0081 

1  3 

1    2 

4 

7 
7 

9 
10 

11 

0,10 

4,58C 

e 

4,5q5 

i( 

4,6o5 

9 

4,614 

9 

4,623 

\ 

4,63: 

9 

0,0100 

i3 
i4 

1   3 
1   3 

4 
4 

5 
5 

7 

8 
g 

9 
10 

10 

12 
i3 

0,1 1 

5,o45 

K 

5,<.55 

K 

5,o65 

It 

5,075 

10 

5,o85 

11 

5,oq5|  10 

0,0121 

7 

1 1 

0,15 

5,5o3 

1  I 

5,5i4 

I  I 

5,525 

1 1 

5,536 

11 

5,547 

1 1 

5,55t 

1 1 

0,01 44 

i5 

2   3 

5 

6 

8 

9 

11 

12 

i4 

o,i3 

5,963 

12 

5.9-4 

12 

5,986 

12 

5,998 

12 

6,010 

1 1 

6,02 

12 

0,0169 

16 

2  3 

5 

6 

8 

10 

1 1 

i3 

i4 

0,14 

6,420 

i3 

6,433 

i3 

6,446 

i3 

6,459 

i3 

6,472 

i3 

6,48d 

12 

0,0196 

17 
18 

2  3 
2  4 

5 
5 

7 
7 

9 
9 

10 
1 1 

13 

i3 

i4 
■  4 

i5 
16 

o,i5 

6,879 

i4 

6,8g3 

i3 

6,906 

14 

6,Q20 

i4 

6,934 

i4 

6,94f 

i3 

0,0225 

19 

2  4 

6 

8 

10 

11 

i3 

i5 

'7 

0,16 

7,33-7 

i5 

7,352 

i5 

7,367 

14 

7,38 1 

i5 

7,3c)6 

i5 

7,4ii 

i4 

o,o256 

0,17 

7,796 

i5 

7,811 

16 

7,827 

16 

7.843 

i^ 

7,(-'58 

i() 

7,87^ 

i5 

0,0389 

20 

2  4 

6 

8 

10 

12 

i4 

16 

18 

0,18 

8,254 

i-j 

8,271 

16 

8,287 

17 

8,3o4 

16 

8,320 

I", 

8,33- 

16 

o,o324 

21 

2  4 

6 

8 

1 1 

i3 

i5 

'7 

19 

o,ig 

8,7" 

18 

8,73o 

17 

8,747 

18 

8,765 

17 

8,782 

I- 

8,79( 

18 

o,o36i 

22 

2  3 

2  4 
2  5 

7 
7 

9 
9 

11 
12 

i3 
i4 

i5 
16 

18 
18 

30 
21 

0,20 

9:'7I 

18 

9,189 

18 

9,207 

'9 

9.336 

if 

9,244 

18 

9,363 

19 

o,o4oo 

24 

2  5 

7 

10 

12 

14 

17 

19 

22 

0,21 

9,629 

19 

9,648 

30 

9,668 

19 

9,687 

19 

9,706 

11, 

9,73? 

19 

0,044 1 

25 

3  5 

8 

i3 

i5 

18 

23 

0,22 

10,087 

20 

1 0, 1 07 

31 

10,128 

30 

10,148 

30 

io,ifi8 

3C) 

10,188 

20 

0,0484 

3  5 
3   5 
3  6 

i3 

i4 
i4 

16 
16 

17 

18 

23 

24 

25 

0,23 

10,545 

22 

10,567 

21 

io,588 

21 

10,609 

21 

io,63o 

21 

io,65i 

21 

0,0529 

26 

8 
8 
8 

10 

21 

0,24 

1 1  ,oo3 

13 

1 1 ,026 

22 

11,048 

22 

1 1 ,070 

33 

1 1 ,092 

32 

ii,ii4 

21 

0,0576 

27 

28 

1 1 
1 1 

19 
20 

22 
22 

0,25 

1 1 ,463 

23 

11,485 

23 

ii,5o8 

23 

ii,53i 

22 

11,553 

23 

11,576 

23 

0,0625 

29 

3  6 

9 

12 

i5 

17 

30 

23 

26 

0,26 

1 1,920 

24 

1 1 ,944 

24 

1 1 ,968 

33 

1 1,991 

24 

12,Ol5 

24 

i2,o3g 

24 

0,0676 

3o 

3  6 

9 

9 

10 

13 

i5 

18 

21 

24 

27 

0,27 

12,378 

25 

i2,4o3 

24 

12,427 

25 

12,453 

25 

12,477 

25 

12,5o2 

24 

0,0729 

3i 

3  6 

12 

16 

19 

23 

25 

28 

0,28 

12,836 

25 

13,861 

36 

12,887 

26 

12.913 

36 

12,939 

25 

12,964 

26 

0,0784 

32 

3  6 

i3 

16 

19 

22 

26 

'9 

3o 

0,29 

13,394 

26 

i3,32o 

27 

1 3,347 

27 

1 3,374 

26 

i3,4oo 

27 

13,427 

26 

0,084 1 

33 

3  7 

10 

i3 

17 

20 

23 

36 

34 

3  7 

10 

14 

17 

20 

34 

27 

3i 

o,3o 

1 3,75 1 

28 

1 3,779 

28 

1 3,807 

27 

1 3,834 

38 

1 3,862 

27 

i3,88g 

27 

0,0900 

0,3 1 

14.209 

29 

i4,238 

38 

14,266 

29 

14,295 

38 

14,333 

26 

i4,35i 

29 

o,og6i 

35 

4   7 

11 

i4 

18 

21 

25 

28 

32 

0,32 

14.667 

29 

i4,6y6 

3o 

14,726 

29 

14,755 

3o 

14,785 

29 

i4,8i4 

29 

0,1024 

36 

4   7 

11 

i4 

18 

22 

25 

29 

33 

0,33 

i5,i25 

35 

i5,i55 

3o 

i5,i85 

3i 

i5,3i6 

3o 

1 5,246 

3o 

15,276 

3o 

o,io8g 

37 

4  7 

11 

i5 

19 

22 

26 

3o 

33 

0,34 

1 5,582 

32 

1 5,614 

3i 

1 5,645 

3i 

15,676 

3i 

15,707 

3i 

1 5,738 

3i 

o,ii56 

38 
39 

4  8 
4  8 

11 
12 

i5 
16 

19 
20 

23 
23 

27 
27 

3o 
3i 

34 
35 

0,35 

i6,o4o 

32 

16,072 

32 

i6,io4 

33 

i6,i36 

32 

16,168 

32 

16,200 

32 

0,1225 

o,36 

16,497 

33 

i6,53o 

34 

i6,564 

33 

16,597 

33 

i6,63o 

33 

1 6,663 

32 

0,1296 

4o 

4  8 

12 

16 

20 

24 

28 

32 

36 

0,37 

16,955 

34 

16.989 

34 

17,023 

M 

17,057 

34 

17,091 

34 

17,135 

33 

0,1369 

4i 

4  8 

12 

16 

21 

25 

29 

33 

37 

0,38 

17,412 

35 

17:447 

35 

17,482 

35 

17,517 

35 

17,552 

35 

17,587 

34 

0,1 444 

42 

4  8 

i3 

17 

21 

25 

=9 

34 

38 

0,39 

17,869 

36 

i74)o5 

36 

1 7,94  > 

36 

17,977 

36 

i8,oi3 

35 

i8,o48 

36 

0,l521 

43 
44 

4  9 
4  9 

i3 
i3 

17 
18 

22 

33 

26 
26 

3o 
3i 

34 
35 

39 
40 

o,4o 

18,326 

37 

i8,363 

37 

18,400 

37 

18,437 

37 

18,474 

36 

i8,5io 

37 

0,1600 

45 
46 
47 
48 

49 

I     t 

i4 
i4 
i4 
i4 
i5 

18 
18 

23 
23 
24 
34 
25 

32 
32 

33 
M 
34 

36 

37 
38 
38 
3g 

4i 
4i 
42 
43 
A4 

0,4 1 

18,784 

37 

18,821 

38 

18,859 

38 

18,897 

38 

18.935 

37 

18,972 

38 

0,1681 

27 
28 

0,42 

19,241 

38 

19,279 

39 

19,318 

39 

19,357 

38 

19:395 

39 

ig,434 

38 

0,1764 

:  9 

28 

0,43 

19,698 

39 

19,737 

40 

19,777 

3q 

19,816 

4o 

19,856 

39 

19,895 

4o 

0,1849 

.      9 

D  10 

5  10 

19 

0,44 

20, 1 54 

4i 

20,195 

4i 

20,336 

40 

30,276 

4i 

20,3i7 

A'- 

20,357 

40 

0,1936 

19 
20 

29 

29 

0,45 

20,611 

42 

2o,653 

4i 

30,694 

42 

30,736 

4i 

20,777 

4t 

20,818 

4i 

0,2025 

5o 

3  10 

i5 

20 

25 

3o 

35 

4o 

45 

o,5o 

22,894 

46 

22,940 

46 

33,986 

46 

23,o33 

46 

23,078 

46 

33,124 

46 

0,2  5oo 

5i 

J  10 

i5 

30 

26 

3i 

36 

4i 
42 
42 

46 

0,55 

25,174 

5i 

25,225 

5i 

25,276 

5i 

25,337 

5o 

25,377 

5i 

25,438 

5o 

o,3o25 

52 

1  10 

16 

2 1 

26 

3i 

36 

4? 

0,60 

27,453 

56 

27,508 

55 

27,563 

56 

27,619 

55 

27,674 

55 

27,729 

55 

o,36oo 

53  - 

'  1 1 

16 

21 

27 
27 

32 

37 
38 

48 

o,65 

59-727 

60 

29,787 

60 

29,847 

61 

39,908 

59 

29,967 

60 

3o,o37 

60 

0,4225 

54  '- 

1 1 

16 

22 

32 

43 

A9 

0,70 

3 1, 999 

65 

32,064 

65 

32,129 

64 

32,193 

65 

32,358 

65 

32,323 

64 

o,4goo 

55  ( 

)  11 

17 

32 

38 

33 

39 

44 

5o 

0,75 

34,367 

70 

34,337 

69 

34.406 

70 

34,476 

69 

34,545 

70 

34,61 5 

69 

0,5625 

56  t 

)  II 

17 

22 

28 

M 

39 

45 

5o 

0,80 

36,533 

74 

36.6o6 

75 

36;68i 

74 

36,755 

74 

36,829 

74 

36,9o3 

74 

o,64oo 

57  f 

11 

17 

23 

29 

M 

4o 

46 

5i 

o,85 

38,793 

80 

38,872 

79 

38,95i 

79 

3g,o3o 

79 

39,109 

79 

39.188 

78 

0,7225 

58  f 

12 

17 

23 

29 

35 

4i 

46 

52 

0,90 

4 1, 049 

84 

4i,i33 

84 

41.217 

84 

4i,3oi 

83 

4 1,384 

84 

4 1, 468 

83 

0,8100 

59  t 

12 

18 

24 

3o 

35 

4i 

47 

53 

0,95 

43,3oo 

90 

43,390 

88 

43,478 

89 

43,567 

89 

43,656 

88 

43,744 

88 

0,9025 

1,00 

45,547 

94 

45,64 1 

94 

45,735 

94 

45,829 

93 

45,922 

93  46.01 51 

93 

1 ,0000 
c2 

60  6 

61  6 
63  6 

63  6 

64  6 

12 

13 
13 

i3 
i3 

18 
18 
'9 
■9 

24 
24 
25 
25 
26 

3o 
3i 
3i 

32 
32 

36 
37 
37 
38 
38 

42 
43 
4i 
44 
45 

48 

t 
5o 
5i 

54 
55 
56 

57 

58 

3,1001  1 

3,1250  1 

3,1501  1 

3,17f 

52 

3,2005  1  3,2258  | 

\  .  {r  -\-  r''  )'^     or  r'* -\-  r  "  "^     nearly.                      | 

456 

457 

458 

459 

460 

461 

462 

463 

464 

■9 

— 

— 



— 



— 

— 

— 

65  7 

i3 

20 

26 

33 

39 

46 

52 

59 

I 

46 

46 

46 

46 

46 

46 

46 

46 

46 

I 

66  7 

i3 

20 

36 

33 

4o 

46 

53 

59 

2 

Qi 

91 

92 

92 

92 

92 

V 

93 

93 

2 

67  7 

i3 

20 

37 

M 

40 

47 

54 

60 

3 

■37 

1 37 

1 37 

1 38 

1 38 

1 38 

1 39 

139 

139 

3 

68  7 

i4 

20 

27 

34 

4i 

48 

54 

61 

4 

182 

i83 

i83 

184 

184 

184 

i85 

i85 

186 

4 

69  7 

14 

21 

28 

35 

41 

48 

55 

62 

5 

228 

229 

229 

275 

23o 

23o 

23 1 

23l 

232 

232 

5 

6 

274 

274 

275 

276 

277 

277 

278 

278 

6 

70  7 

i4 

21 

28 

35 

42 

49 

56 

63 

7 

319 

330 

321 

321 

322 

333 

323 

324 

325 

7 

80  8 

16 

24 

32 

4o 

48 

56 

64 

72 

8 

365 

366 

366 

367 

368 

369 

370 

370 

371 

8 

90  9 

18 

27 

36  45 

54 

63 

72 

81 

4io 

4ii 

4l2 

4i3 

4i4 

4i5 

416 

417 

418 

9 

|ioo  10 

20 1 

3o 

io  5o 

So 

70 

80 

22 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-j-i"",  and  the  chord  c  being  given. 


Sum  of  the  Radii  r-f-r".                                                                                                                | 

Chord 
C. 

2,55 

2,56 

2,57 

2,58 

2,59 

Days  |dir. 

2,60 

2,61 

2,62 

Days  |dir. 

2,63 

Days  |dif. 

2,64 

Days|dif. 

Days  |dir. 

Days  |dil'. 

Days  |dif. 

UaysldiC. 

Days  |dir. 

Day»  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,464 

I 

0,465 

I 

0,466 

I 

0,467 

I 

0,468 

I 

0,469 

1 

0,470 

0 

0,470 

1 

0,471 

I 

0,472 

I 

0,0001 

0,02 

0,928 

3 

0,930 

3 

0,932 

2 

0,934 

2 

0,936 

I 

0,937 

2 

0,939 

2 

0,941 

2 

0,943 

2 

0,945 

I 

0,0004 

o,o3 

i,3q2 

3 

1,395 

3 

1 ,398 

3 

I,4oi 

2 

i.4o3 

3 

1, 406 

3 

1,409 

2 

i,4ii 

3 

I,4l4 

3 

1,417 

2 

o,ooog 

o,o4 

1,857 

3 

1,860 

4 

1,864 

3 

1,867 

4 

1,871 

4 

1,875 

3 

1,878 

4 

1,882 

3 

1,885 

4 

1,889 

4 

0,0016 

o,o5 

2,321 

4 

2,325 

5 

2,33o 

4 

2,334 

5 

2,33g 

4 

2,343 

5 

2,348 

4 

2,352 

5 

2,357 

4 

2, 36 1 

5 

0,0025 

0,06 

2,785 

5 

2,790 

6 

2,796 

5 

2,801 

6 

2,807 

5 

2,812 

5 

2,817 

6 

2,823 

5 

2,828 

6 

2,834 

5 

o,oo36 

0,07 

3,249 

6 

3,255 

7 

3,362 

6 

3.268 

6 

3,274 

7 

3,281 

6 

3,287 

6 

3,293 

7 

3,3oo 

6 

3,3o6 

6 

0,0049 

0,08 

3,7i3 

-7 

3,720 

8 

3,728 

7 

3;735 

7 

3,742 

7 

3,749 

7 

3,756 

8 

3,764 

7 

3,771 

7 

3,778 

7 

0,0064 

o,og 

4,177 

8 

4,i85 

8 

4,193 

9 

4,203 

8 

4,210 

8 

4,218 

8 

4,226 

8 

4,234 

8 

4,242 

8 

4,25o 

8 

0,008 1 

0,10 

4,64i 

9 

4,65o 

9 

4,659 

9 

4,668 

9 

4,677 

10 

4,687 

9 

4,6g6 

9 

4,7o5 

8 

4,7i3 

9 

4,722 

9 

0,0100 

0,11 

5,io5 

10 

5,ii5 

10 

5,125 

10 

5,i35 

10 

5,i45 

10 

5,i55 

10 

5,i65 

10 

5,175 

10 

5,i85 

10 

5,195 

9 

0,0121 

0,13 

5,5fi9 

II 

5,58o 

1 1 

5.591 

II 

5,602 

11 

5,6 1 3 

1 1 

5,624 

10 

5,634 

11 

5,645 

II 

5,656 

1 1 

5,667 

10 

0,01 44 

o,i3 

6,o33 

12 

6,045 

12 

6,o57 

12 

6,069 

1 1 

6,080 

12 

6,092 

12 

6,104 

12 

6,116 

11 

6,127 

12 

6,139 

12 

0,01 6g 

o,i4 

6,497 

i3 

6,5io 

i3 

6,523 

12 

6,535 

i3 

6,548 

i3 

6,56i 

12 

6,573 

i3 

6,586 

12 

6,5g8 

i3 

6,611 

i3 

0,01  g6 

0,1 5 

6,961 

14 

6,975 

i4 

6,989 

i3 

7,002 

i4 

7,016 

i3 

7,02g 

i4 

7,043 

i3 

7,o56 

i4 

7,070 

i3 

7,o83 

i4 

0,0225 

0,16 

7,425 

j5 

7,440 

i4 

7,454 

i5 

7,469 

14 

7,483 

i5 

7,498 

i4 

7,5i2 

14 

7,526 

i5 

7,541 

i4 

7,555 

14 

o,0256 

0,17 

7,889 

16 

7,9o5 

i5 

7,920 

i5 

7,935 

16 

7,951 

i5 

7,966 

i5 

7,981 

16 

7,997 

i5 

8.012 

i5 

8,027 

i5 

0,028g 

0,18 

8,353 

16 

8,36q 

17 

8,386 

16 

8,402 

16 

8.418 

17 

8,435 

16 

8,45i 

16 

8,467 

16 

8,483 

16 

8,499 

16 

o,o324 

0,19 

8,817 

17 

8,834 

17 

8,85i 

18 

8,869 

17 

8,886 

17 

8,903 

17 

8,930 

17 

8,937 

17 

8,g54 

17 

8,971 

17 

o,o36i 

0,20 

9,281 

18 

9,299 

18 

9,317 

18 

g,335 

18 

9,353 

18 

9,371 

18 

9,389 

18 

9,407 

18 

9,425 

18 

9,443 

18 

o,o4oo 

0,21 

9-744 

20 

9,764 

19 

9,783 

19 

g,8o3 

19 

9,831 

19 

9,84o 

18 

9,858 

'9 

9,877 

19 

9,896 

19 

9,9' 5 

19 

0,044 1 

0,22 

10,208 

20 

10,228 

20 

10,248 

20 

10,268 

30 

10,388 

20 

io,3o8 

30 

10,328 

19 

10,347 

20 

10,367 

20 

10,387 

20 

0,0484 

0,23 

10,672 

21 

10,693 

21 

10,714 

30 

10,734 

21 

10,755 

21 

10,776 

21 

10,797 

21 

10,818 

20 

io,838 

21 

io,85g 

20 

o,o52g 

0,24 

ii,i35 

22 

ii,i57 

22 

11,179 

22 

1 1,201 

22 

I  1,223 

21 

11,244 

33 

1 1,266 

21 

11,287 

22 

11,309 

22 

11,331 

21 

0,0576 

0,25 

11,599 

23 

11,622 

33 

11,645 

22 

1 1 ,667 

23 

I  1 ,690 

22 

11,712 

33 

11,735 

22 

11,757 

23 

11,780 

22 

11,802 

23 

0,0625 

0,26 

i2,o63 

23 

1 2  ,oS6 

34 

12,1 10 

23 

i3,i33 

24 

I2,i57 

24 

12,181 

23 

13,204 

23 

13,337 

24 

12,25l 

23 

12,274 

23 

0,0676 

0,27 

12,526 

35 

I2,55i 

24 

13,575 

25 

1 3 ,600 

34 

12,624 

25 

1 3 ,649 

24 

12,673 

24 

12,697 

25 

12,722 

24 

12,746 

24 

0,0729 

0,28 

12,990 

25 

1 3,01 5 

26 

1 3,04 1 

25 

1 3,066 

25 

13,091 

26 

i3,ii7 

25 

i3,i42 

35 

13,167 

25 

13,192 

25 

i3,2i7 

25 

0,0784 

0,2g 

1 3,453 

26 

1 3,479 

27 

i3,5o6 

26 

i3,532 

26 

1 3,558 

27 

1 3,585 

26 

1 3,61 1 

26 

1 3,637 

26 

1 3,663 

26 

13,689 

26 

0,0841 

o,3o 

13,916 

28 

1 3,944 

27 

13,971 

27 

13,998 

27 

i4,025 

28 

i4,o53 

27 

14.080 

27 

14,107 

27 

i4,i34 

26 

i4,i6o 

27 

0,0900 

o,3i 

i4,38o 

28 

I 4, 408 

28 

1 4,436 

28 

i4,464 

28 

14,492 

28 

i4,53o 

28 

i4,548 

28 

14,576 

28 

1 4,604 

28 

i4,632 

28 

0,0961 

0,32 

14,843 

29 

14,872 

29 

14,901 

29 

1 4,930 

29 

14,959 

29 

14,988 

29 

15,017 

29 

1 5,046 

29 

15,075 

28 

i5,io3 

29 

0,1024 

0,33 

i5,3o6 

3o 

1 5,336 

3o 

1 5,366 

3o 

15,396 

3o 

15,426 

3o 

1 5,456 

3o 

1 5,486 

29 

i5,5i5 

3o 

1 5,545 

3o 

15,575 

29 

0,1  o8g 

0,34 

15,769 

3i 

1 5,800 

3i 

i5,83i 

3i 

15,862 

3i 

15,893 

3i 

15,924 

3o 

15,954 

3i 

1 5,985 

3i 

16,016 

3o 

16,046 

3o 

0,11 56 

0,35 

l6,232 

33 

16,264 

33 

16,396 

32 

16,328 

32 

i6,36o 

3i 

16,391 

32 

16,423 

3i 

16,454 

32 

16,486 

3i 

16.517 

32 

0,1225 

o,36 

16,695 

33 

16,728 

33 

16,761 

33 

16,794 

32 

16,826 

33 

16,859 

32 

16,891 

33 

16,924 

32 

16,956 

32 

16,988 

33 

0,1296 

0,37 

I7,i58 

34 

17,192 

34 

17,226 

33 

17,259 

34 

17,393 

33 

17,326 

34 

17,360 

33 

I7,3g3 

33 

17,426 

34 

1 7,460 

33 

0.1 36g 

o,38 

17,621 

35 

17,656 

35 

17,691 

34 

17,725 

34 

■7,759 

35 

17,794 

34 

17,828 

34 

17,862 

35 

17,897 

34 

17,931 

34 

0,1 444 

0,39 

18,084 

36 

18,120 

35 

i8,i55 

36 

18,191 

35 

18,226 

35 

18,261 

35 

i8,2g6 

36 

18,333 

35 

18,367 

35 

18,402 

35 

0,l52I 

o,4o 

18,547 

36 

i8,583 

37 

18,620 

36 

i8,656 

36 

18,692 

37 

18,729 

36 

18,765 

36 

18,801 

36 

18,837 

36 

18,873 

35 

0,1600 

0,4 1 

19,010 

37 

19,047 

37 

19,084 

38 

19,122 

37 

19,159 

37 

19,196 

37 

ig,233 

37 

19,270 

37 

19,307 

36 

19,343 

37 

0,1681 

0,42 

19,472 

38 

19,510 

39 

19,549 

38 

19,587 

38 

19,625 

38 

ig,663 

38 

19,701 

38 

'9,739 

38 

19,777 

37 

19,814 

38 

0,1764 

0,43 

19,935 

39 

19-974 

39 

30,01  3 

39 

20,o52 

39 

20,ogi 

39 

3o,i3o 

39 

20,169 

39 

20,208 

38 

20,346 

39 

20,285 

39 

0,1849 

0,44 

20,397 

40 

20,437 

40 

20,477 

4o 

20,517 

40 

20,557 

40 

20,597 

4o 

20,637 

40 

20,677 

39 

20,716 

4o 

20,756 

39 

0,1  g36 

0,45 

20,859 

42 

20,901 

4i 

20,942 

40 

20,982 

4i 

21,023 

4i 

2 1 ,064 

4i 

2i,io5 

40 

21,145 

4i 

21,186 

4o 

21,226 

4i 

0,2025 

o,5o 

23,170 

46 

23,3l6 

45 

23,261 

46 

23,307 

45 

23,352 

46 

23,398 

45 

23,443 

45 

23,488 

45 

33,533 

45 

23,578 

45 

o,25oo 

0,55 

25,478 

5i 

25,52g 

5o 

25,579 

5o 

25,639 

5o 

25,679 

5o 

25,72g 

5o 

25,779 

49 

25,838 

5o 

25,878 

49 

25,927 

5o 

o,3o25 

0,60 

27,784 

55 

27,839 

55 

27,894 

55 

27,949 

54 

38,oo3 

55 

28,o58 

54 

28,1 12 

54 

28,166 

55 

28,221 

54 

28,275 

54 

o,36oo 

o,65 

30,087 

60 

3o,i47 

59 

3o,2o6 

59 

3o,265 

60 

3o,325 

59 

3o,384 

59 

3o,443 

59 

3o,5o2 

58 

3o,56o 

59 

30,619 

59 

0,4225 

0,70 

33,387 

64 

32,45i 

64 

32,5i5 

64 

32,579 

64 

32,643 

64 

32,707 

64 

32,771 

63 

32,834 

63 

32,897 

64 

32,g6i 

63 

0,4900 

0,75 

34,684 

69 

34,753 

68 

34,821 

69 

34,890 

69 

34,959 

68 

35,027 

68 

35,095 

68 

35,i63 

68 

35,23i 

68 

35,299 

68 

0,5625 

0,80 

36,977 

73 

37,o5o 

74 

37,124 

73 

37,197 

74 

37,271 

73 

37,344 

73 

37,4.7 

72 

37,489 

73 

37,562 

72 

37,634 

73 

0,6400 

o,85 

39,266 

79 

39,345 

78 

3g,43  3 

78 

39,501 

78 

39,579 

78 

3g,657 

77 

39,734 

78 

39,812 

77 

39,889 

77 

39,966 

77 

0,7225 

0,90 

4i,55i 

84 

4 1, 635 

83 

41,718 

83 

4 1 ,800 

83 

4i,883 

82 

4i,g65 

83 

42,048 

83 

42,i3o 

82 

42,212 

83 

42,294 

81 

0,8100 

0,95 

43,832 

88 

43,920 

88 

44,008 

88 

44,096 

87 

44,i83 

87 

44,270 

87 

44,357 

87 

44ÀM 

87 

44,53 1 

86 

44,617 

87 

o,go25 

1,00 

46,108 

93 

46,201 

93 

46,294 

92 

46,386 

92 

46,478 

92 

46,570 

92 

46,663 

92 

46,754 

91 

46,845 

92 

46,937 

91 

1 ,0000 

3,2513 

3,2768 

3,3025 

3,3282 

3,3541 

3,3800 1 

3,4061 

3,4322 

3,4585 1 

3,4848  1 

C^ 

è  .  (r  H-  r  "  )•'     or 

r^  -{-  r"^    nearly. 

1 

462 

463 

464 

465 

466 

467 

468 

469 

470 

471 

472 

46 

46 

46 

47 

47 

47 

47 

47 

47 

47 

47 

92 

93 

93 

93 

93 

93 

94 

94 

94 

94 

94 

i3g 

i3g 

i3g 

1 40 

i4o 

i4o 

1 40 

i4i 

i4i 

i4i 

142 

i85 

1 85 

186 

186 

186 

187 

187 

188 

188 

188 

189 

23l 

232 

232 

233 

233 

234 

234 

235 

235 

236 

236 

277 

278 

278 

279 

280 

280 

281 

281 

282 

283 

283 

323 

324 

325 

326 

326 

327 

328 

328 

329 

33o 

33o 

370 

370 

371 

372 

373 

374 

374 

375 

376 

377 

378 

4i6 

417 

418 

419 

419 

420 

421 

422 

423 

424 

425 

473 


47 

I 

P5 

3 

142 

3 

189 

4 

237 

5 

284 

6 

33i 

7 

378 

8 

426 

9 

TABLE    II.  —  To  linil  llie  tinu-  T :  (lie  sum  of  (he  lailii  r-{-r",  and  the  chord  c  beino;  given. 


Sum  ol'  Iho  Ra'lii  r-f-r". 


Chord 
C. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,u5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,1  I 

0,I2 

0,1 3 
0,1 4 

o,,5 

0,lt) 

0,17 
0,18 
0,19 

0,20 

0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 

0^2 

0.43 
0,44 

0,45 
o,5o 
0,55 
0,60 
0,65 


0,73 
0,80 
0,85 
o,go 
0,95 
1,00 


2,65 


Davs  {dif. 


0,000 
0,4-3 
0,946 

i,4i( 
1,89 

2,366 
2.839 
3.3i2 

3,785 
4,258 

4,73i 
5,204 
5,6^7 
6,i5i 
6,624 

7,09- 
7,569 
8,042 
8,5i5 
8,988 

9,461 

9,934 

10,407 

10,879 

11,352 

11,825 
12,297 
12,770 
13,242 
i3,7i5 

14,187 
14,660 
I 5,1 32 
i5,6o4 
16,076 

16,549 
17,021 
17,493 
17,965 
18,437 

18.908 
19.380 
19,852 
20,324 
20,795 

2 1 ,267 
23,623 
25.977 
28;'329 
30,678 
33,024 

35,367 
37,707 
40,043 
42,375 
44,704 
47,028 


2,66 


Days  |dif. 


3.5113 


0,000 

0,474 

1 

0,948 

2 

1.422 

; 

1,896 

4 

2,3-0 

5 

2,844 

6 

3,3i8 

- 

3,-Q2 

- 

4,2(10 

8 

4.740 

Q 

■3.214 

\< 

5,(jSS 

1 1 

6.102 

1  ) 

6,636 

12 

7,110 

t3 

7,584 

i4 

8,o58 

t5 

8,53i 

16 

9,oo5 

17 

9'4-9 

18 

9,953 

18 

10,426 

20 

10,900 

20 

11,373 

22 

11,847 

22 

12,321 

23 

12,794 

24 

13,267 

25 

i3,74i 

26 

i4,2i4 

27 

14.687 

28 

i5,i6i 

28 

1 5,634 

2Q 

16,107 

3o 

i6,58o 

3l 

i7,o53 

32 

17,526 

33 

17,999 

34 

18,472 

34 

18,944 

36 

19.417 

37 

19,890 

3- 

20,362 

38 

2o,835 

39 

2i,3o7 

40 

23,668 

AÂ 

26,026 

4q 

28,382 

54 

3o,736 

58 

33,087 

63 

35,435 

67 

37,779 

72 

4o,I20 

7-^ 

42.457 

81 

44,790 

86 

47,119 

90 

2,67 


Unys  liUr. 


3,5378 


0,000 
0,475 

o.gSo 
1,425 
1 ,900 

2.375 
2 ,85o 
3,325 
3.-99 

4.2-4 

4.749 
5.224 
5.699 
(J.1-4 
6,(548 

7.123 
7,598 
8,073 
8,547 
9,02 

9.497 

9.971 

10,446 

10,920 

11,395 


12,344 
12,81 
13,292 
13,767 

14,241 
i4,7i5 
15,189 
1 5,663 
16,1 37 

16,611 
17,085 
17,559 
i8,o33 
i8,5o6 

18,980 
19,454 
19-927 

2O,400 
20,874 

21,347 
23,712 
26,075 

28,436 
30,794 
33,i5o 

35,5o2 
37,85 1 
40,197 
42,538 
44,876 
47.209 


2,68 


Days  |dir. 


3,5645 


0,000 
0,476 
0,952 
1,427 
1,903 

2,379 

2.855 
3,33i 
3, So 
4,282 

4,758 

5,234 

5," 

(■),i85 

6,661 

7,i3- 
7.612 
8,088 
8,563 
9,039 

9.5i4 

9,990 

10,465 

10,941 

ii,4i6 

11,892 
1 2 ,367 
12,842 
i3,3i7 
13,792 

14.268 
1 4,743 
i5,2i8 
15,693 
16,167 

16,642 
17,117 
17,592 
18,066 
i8,54i 

19,016 
19,490 
19,964 
20,439 
20,913 

21,387 
23,757 
26,125 
28,490 
3o,853 

33,212 

35,56g 
37,923 
40,273 
42.619 
44,962 
47,3oo 


19 


3,5912 


2,69 


Days  (dif. 


0,000 
0,477 
0,953 
i,43o 
'.■907 

2.384 
2,860 
3,337 
3,814 
4,290 

4,767 

5,244 

5,720 

6.19 

6,673 

7,1 5o 
7,626 
8,io3 
8,579 
9,o56 

9,532 
10,009 
io,485 
10,961 
11,438 

11.914 
12,390 
12,866 
13.342 
i3,8i8 

14,294 
14,770 
1 5,246 

l5,722 
16,198 

16,673 
17.149 
17,625 
18,100 
18,576 

i9,o5i 
19,527 
20,002 
20,477 
20.952 

21,427 
23,802 
26,174 
28,543 
30,911 
33,275 

35,637 
37,995 
40,349 
42,700 
45,047 
47,390 


3,6181 


2,70 


Days  jdif. 


0,000 

0,47 
0,955 
1,433 
1,910 

2,388 
2,866 
3,343 
3,821 
4,298 

4,776 
5,253 
5,73i 
6,208 
6,686 

7,i63 

7,64i 

8,11 

8,595 

9.073 

9,55o 
10,027 
io,5o4 
10,982 
11,459 

1 1  ,g36 
12,4  " 
12,890 
1 3,367 
1 3,844 

i4,32i 
14.798 
15,274 
1 5.751 
16,228 

16,704 
17,181 
17,658 
i8,i34 
18,610 

19,087 
ig,563 
20,o3g 
20,5i5 
20,991 

2 1 ,467 
23,846 
26,223 
28,597 
30,96g 
33,338 

35,704 
38, 066 
40.426 
42,781 
45,i33 
47,480 


3,6450 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
o,oû(i4 
0,0081 

0,0100 
0,01 2 1 
0,01 44 

l^Olfxj 

0,0196 

0,0225 
o,o256 
0,028g 
o,o324 
o,o36i 

o,o4oo 
0,044 1 
0,0484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,0841 

0,0900 
0,0961 
0,1024 
0,1089 
0,1 156 

0,1225 
0,1296 
0,1 36g 
0,1444 

0,l52I 

0,1600 

0,1681 

0,1764 
0,1849 
0,1936 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 

~72" 


(r  + 


nearly. 


471 

472 

473 

474 

475 

476 

477 

47 

47 

47 

47 

48 

48 

48 

94 

94 

95 

95 

95 

95 

95 

i4i 

142 

142 

142 

143 

143 

143 

188 

189 

igo 

190 

190 

191 

2  36 

236 

237 

237 

238 

238 

239 

283 

283 

284 

284 

285 

286 

286 

33o 

33o 

33 1 

332 

333 

333 

334 

3-7 

378 

3-8 

379 

38o 

38 1 

382 

424 

425 

426 

427 

428 

428 

429 

478 

48 

143 
191 

23g 
287 
335 
382 

43f. 


Trop,  parts  for  ilto  sum  ut'  tho  Kadii. 
I  I  2  I  3 I 4  |5|6|7|8|9 


53 

54 

55 
56 

57 
58 

59 

60 
61 
62 
63 
64 

65 
66 
67 
68 
69 

70 
80 

90 

100 


3ol4o 


56 
54  63 
6o|  70 


23 
23 

24 

a5 
26 

27 
28 

29 
3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 
4o 

4i 
4i 
42 
43 
4Â 

45 
46 

47 


5, 

54 

55 

49  56 


52  59 

53  5g 


60 
61 
62 

63 
72 
81 

90 


aU 


TABLE 

II.- 

-To  find  the  time 

T; 

the  sum  of  the  radii  r 

+  '• 

',  and  the  chord  c 

being  given. 

Sum  of  the  Kadii  r-\-r".                                                                                                              | 

Chord 
C. 

2,71 

2,72 

2,73 

2,74 

2,75 

2,76 

Days  |dir. 

2,77 

Days  Idif. 

2,78 

Days  |dif. 

2,79 

2,80 

Daysldi 

Days  Idif. 

Days  |dif. 

Days  |dif. 

Days  |dif. 

Days  |dif. 

Days|dit'. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,478 

I      0,479 

I 

0,480 

I 

o,48i 

1 

0,482 

1 

o,483 

1 

0,484 

1 

o,485 

I 

0,486 

0 

0,486 

I 

0,000 1 

0,02 

0,957 

2       0,959 

2 

0.96 1 

I 

0,962 

2 

0,964 

2 

0,966 

2 

0.968 

1 

0,969 

2 

0,971 

3 

0,973 

1 

0,0004 

o,o3 

1,435 

3     1,438 

3 

1, 44 1 

2 

1,443 

3 

1,446 

3 

1,449 

2 

1, 45 1 

3 

1,454 

2 

1,456 

3 

1,459 

3 

0,0009 

o,o4 

1,914 

3     1,917 

4 

1,921 

4 

1,925 

3 

1,928 

4 

1,932 

3 

1,935 

3 

1,938 

4 

1,942 

3 

1,945 

4 

0,0016 

o,o5 

2,392 

5     2,397 

4 

2, 40 1 

5 

2,406 

4 

2,4l0 

4 

2,4i4 

5 

2,419 

4 

2,423 

4 

3,427 

5 

2,432 

4 

0,0025 

0,06 

2,871 

5     2,876 

5 

3,881 

6 

2,887 

5 

2,892 

5 

2,897 

5 

2,902 

6 

2,908 

5 

2,913 

5 

2,918 

5 

o,oo36 

0,07 

3,349 

7     3,356 

6 

3,362 

6 

3,368 

6 

3,374 

6 

3,38o 

6 

3,386 

6 

3,392 

6 

3,398 

7 

3,4o5 

6 

0,0049 

0,08 

3,828 

7     3,835 

7 

3,842 

7 

3,849 

7 

3.856 

7 

3,863 

7 

3,870 

7 

3,877 

7 

3,884 

7 

3.8qi 

7 

0,0064 

0,09 

4,3o6 

8    4,3 i4 

8 

4,322 

8 

4,33o 

8 

4,338 

8 

4,346 

8 

4,354 

7 

4,36i 

8 

4,369 

8 

4,377 

8 

0,008 1 

0,10 

4,785 

8    4,793 

9 

4,802 

9 

4,811 

9 

4.820 

9 

4,829 

8 

4,837 

9 

4,846 

9 

4,855 

8 

4,863 

9 

0,0100 

o,u 

5.263    I 

0    5,273 

9 

5,383 

10 

5,293 

10 

5,3o2 

9 

5,3ii 

10 

5,321 

10 

5,33i 

9 

5,340 

10 

5,35o 

9 

0,0121 

0,12 

5,74 1    I 

I     5,752 

II 

5,763 

10 

5,773 

II 

5,784 

10 

5,794 

11 

5,8o5 

10 

5,81 5 

11 

5,826 

10 

5,836 

10 

0,01 44 

o,i3 

6,220    r 

I     6,23i 

12 

6,243 

II 

6,254 

12 

6,266 

11 

6,277 

11 

6,288 

12 

6,3oo 

11 

6,3 11 

II 

6,322 

12 

0,01 69 

0,1 4 

6,698    I 

2     6,710 

i3 

6,733 

13 

6,735 

12 

6,747 

i3 

6,760 

13 

6,772 

12 

6,784 

12 

6,796 

12 

6,808 

i3 

0,0196 

0,1 5 

7,176    I 

4    7,190 

i3 

7,2o3 

i3 

7,216 

i3 

7,229 

i3 

7,242 

i3 

7,255 

i4 

7,269 

i3 

7,282 

i3 

7,295 

i3 

0,0225 

0,16 

7,655    I 

4    7,669 

i4 

7,683 

i4 

7,697 

i4 

7,711 

i4 

7,725 

i4 

7,739 

14 

7,753 

i4 

7,767 

i4 

7,781 

i4 

0,0256 

0,17 

8,i33    I 

5     8,i48 

i5 

8,i63 

i5 

8,178 

i5 

8,193 

i5 

8,208 

i5 

8.223 

i4 

8,237 

i5 

8,252 

i5 

8.367 

i5 

0,0289 

0,18 

8,611     I 

6    8,627 

16 

8,643 

16 

8,659 

16 

8,675 

i5 

8,690 

16 

8,706 

16 

8,722 

16 

8,738 

i5 

8,753 

16 

o,o324 

0,19 

9,o8g    I 

7     9>'o6 

17 

9,123 

17 

9,i4o 

16 

9,1 56 

17 

9,173 

17 

9,190 

16 

9,206 

17 

9,223 

16 

9,239 

17 

o,o36i 

0,20 

9,568    I 

7    9,585 

18 

9,6o3 

17 

9,620 

18 

9,638 

18 

9,656 

17 

9,673 

18 

9.691 

17 

9,708 

17 

9-725 

18 

o,o4oo 

0,21 

io,o46    I 

8  10,064 

19 

io,o83 

18 

10,101 

19 

10,120 

18 

io,i38 

18 

10,1 56 

19 

10,175 

18 

10,193 

18 

10,31 1 

'9 

o,o44i 

0,22 

10,524    I 

9  10,543 

20 

io,563 

'9 

io,583 

19 

10,601 

20 

10,621 

19 

io,64o 

19 

1 1 ,65q 

'9 

10,678 

19 

10,697 

'9 

o,o484 

0,23 

1 1 ,002    2 

0  11,022 

21 

1 1,043 

20 

ii,o63 

20 

ii,o83 

20 

1 1 . 1 o3 

20 

11,123 

20 

11,143 

20 

ii,i63 

30 

ii,iS3 

20 

0,0529 

0,24 

1 1 ,480    2 

1   ii,5oi 

31 

11,522 

21 

11,543 

22 

11,565 

21 

11,586 

21 

1 1 ,607 

21 

11,628 

20 

1 1 ,648 

21 

1 1 ,669 

21 

0,0576 

0,25 

11,958    2 

2  1 1 ,980 

22 

I  2 ,002 

22 

12,024 

22 

12,046 

22 

13,068 

22 

12,090 

23 

12,112 

31 

i2,i33 

22 

I3,i55 

22 

0,0625 

0,26 

12,436    2 

3  12,459 

23 

12,482 

23 

i2,5o5 

23 

12,528 

22 

i2,55o 

23 

12,573 

23 

12,596 

22 

12,618 

23 

13,641 

23 

0,0676 

0,27 

12,914    2 

4  13,938 

34 

12,962 

23 

12,985 

24 

13,009 

24 

i3,o33 

23 

i3,o56 

24 

1 3,080 

23 

i3.io3 

24 

13,127 

23 

0,0729 

0,28 

13,392    2 

4  i3,4i6 

25 

1 3, 44 1 

25 

1 3,466 

24 

13,490 

25 

i3,5i5 

34 

i3,53g 

25 

1 3,564 

24 

i3,588 

25 

i3,6i3 

24 

0,0784 

0,29 

13,870    2 

5  13,895 

26 

13,921 

25 

1 3,946 

36 

13,972 

25 

1 3,997 

26 

i4,o23 

25 

i4,o48 

25 

14,073 

35 

14,098 

26 

o,o84i 

o,3o 

14,347    3 

7  14,374 

26 

1 4,400 

27 

14,427 

26 

i4,453 

26 

i4,479 

27 

i4,5o6 

26 

i4,532 

26 

i4,558 

26 

14,584 

26 

o,ogoo 

0,3 1 

14,825    2 

7  i4,853 

38 

14,880 

27 

14,907 

27 

14,934 

28 

14,962 

27 

14,989 

27 

i5.oi6 

27 

1 5,043 

27 

15.070 

27 

0,0961 

0,32 

i5,3o3    ? 

8  i5,33i 

28 

15,359 

28 

1 5,387 

29 

i5,4i6 

28 

1 5,444 

28 

1 5,472 

28 

i5,5oo 

27 

1 5, 5 37 

28 

1 5,555 

28 

0,1024 

0,33 

15,780    3 

0  i5.8io 

29 

i5,83q 

29 

1 5,868 

29 

15,897 

29 

15,936 

29 

1 5,955 

28 

15.983 

29 

16,012 

29 

1 6,04 1 

29 

0,1089 

0,34 

i6,258    3 

0  16,288 

3o 

i6,3i8 

3o 

16,348 

3o 

16,378 

3o 

16,408 

29 

16,437 

3o 

16,467 

3o 

16,497 

29 

16,526 

3o 

0,1 1 56 

0,35 

16,735    3 

I   16,766 

3i 

16,797 

3i 

16,838 

3i 

16,859 

3i 

16,890 

3o 

16,920 

3i 

16,951 

3o 

16,981 

3i 

17,012 

3o 

0,1235 

o,36 

I7,2i3    3 

3  17,345 

32 

17,277 

3i 

17,308 

32 

17,340 

3i 

17.371 

33 

i7,4o3 

3i 

17,434 

32 

17,466 

3i 

17,497 

32 

0,1296 

0,37 

17,690    3 

3  17,723 

33 

17,756 

32 

17,788 

33 

17,821 

32 

17,853 

33 

17,886 

32 

17.918 

33 

17,950 

33 

17,983 

32 

0,1369 

o,38 

18,168    3 

3  18,201 

34 

18,235 

33 

18,268 

34 

i8,3o2 

33 

18,335 

33 

i8,368 

34 

i8,4o2 

33 

18,435 

33 

18,468 

33 

0,1 444 

0,39 

18,645    3 

4  18,679 

35 

18,714 

34 

18,748 

34 

18,782 

35 

18,817 

34 

i8,85i 

34 

i8,885 

34 

18,919 

34 

18,953 

34 

0,1 52  I 

o,4o 

19,122    C 

6  19,1 58 

35 

19,193 

35 

19,238 

35 

19,263 

35 

19,398 

35 

19,333 

35 

19,368 

35 

19,403 

35 

19,438 

35 

0,1600 

0,4 1 

19.599    : 

7  19,636 

36 

19,672 

36 

19,708 

36 

19,744 

36 

19,780 

36 

19,816 

36 

19,853 

36 

19,888 

35 

19,923 

36 

0,1681 

0,42 

20,076    . 

8  2o,ii4 

37 

30,1 5i 

37 

20,188 

37 

20,225 

36 

30,261 

37 

20,398 

37 

20,335 

37 

20,372 

36 

20,408 

37 

0,1764 

0,43 

20,553    , 

8  20,591 

38 

20,629 

38 

30,667 

38 

20,705 

38 

20,743 

38 

30,781 

37 

20,818 

38 

20,856 

37 

2o,8q3 

38 

0,1849 

0,44 

2 1  ,o3o   , 

g  21,069 

39 

21,108 

39 

2I,l47 

39 

21,186 

38 

21,224 

39 

21,263 

38 

2i,3oi 

39 

21,340 

38 

2 1 ,378 

38 

0,1936 

0,45 

21,507   i 

!o  21,547 

40 

21,587 

39 

21,626 

40 

21,666 

4o 

21,706 

39 

21,745 

39 

21,784 

40 

21,824 

39 

21,863 

39 

0,2025 

o,5o 

23,890   ^ 

i5  23,935 

44 

23,979 

44 

24,023 

44 

24.067 

44 

24,111 

44 

24,i55 

44 

24,199 

43 

24,242 

44 

24,286 

44 

o,25oo 

0,55 

26,2-ri    i 

:9  26,320 

49 

26,369 

48 

26,417 

49 

26,466 

48 

26,5 1 4 

49 

26,563 

48 

26,61 1 

48 

26,659 

48 

26,707 

48 

o,3o25 

0,60 

28,65o    ; 

)3  28,703 

54 

28,757 

53 

28,810 

53 

28,863 

52 

28,915 

53 

28,968 

53 

29,021 

53 

29,073 

53 

29,126 

52 

o,36oo 

0,65 

31,026 

J8  3 1, 084 

58 

3l,!42 

57 

31,199 

58 

31.257 

57 

3i,3i4 

57 

3i,37i 

57 

31,428 

57 

3 1, 485 

57 

3 1, 542 

57 

0,4225 

0,70 

33,400    ( 

33  33,462 

62 

33,524 

62 

33,586 

62 

33,648 

62 

33,710 

62 

33,772 

61 

33,833 

62 

33,895 

61 

33,956 

61 

0,4900 

0,75 

35,771    ( 

56  35,837 

67 

35,904 

67 

35,971 

66 

36,o37 

66 

36,io3 

66 

36,169 

66 

36,235 

66 

36,3oi 

66 

36,367 

66 

0,5625 

0,80 

38,i38 

71   38,209 

71 

38,280 

72 

38,352 

70 

38,422 

71 

38,493 

71 

38,564 

70 

38,634 

71 

38,7o5 

70 

38,775 

70 

o,64oo 

o,85 

4o,5o2 

76  40,578 

75 

4o,653 

76 

40,729 

76 

4o,8o5 

75 

40,880 

75 

40,955 

75 

4i,o3o 

75 

4i,io5 

75 

41,180 

75 

0,7225 

0,90 

42,862 

3o  42,942 

81 

43,023 

80 

43,io3 

80 

43,i83 

80 

43,263 

80 

43,343 

79 

43,422 

80 

43.5o2 

79 

43,58i 

79 

0,8100 

o,g5 

45,218 

35  45,3o3 

85 

45,388 

85 

45,473 

85 

45,558 

84 

45,642 

85 

45,727 

84 

45,811 

84 

45,895 

84 

45,979 

83 

0,9025 

1,00 

47,570 

30  47,660 

90 

47,750 

89 

47,839 

89 

47,928 

89 

48,017 

89 

48,106 

89 

48,195 

89 

48,284 

88 

48,372 

88 

1 ,0000 

3,672 

1     3,6992 

3,7265 

3,7538 

3,7813 

3,8088 

3,8365 

3,8642 

3,8921 1 

3,9200 

c" 

J  .  (r  +  r")'     01 

7-*  +  r"^   nearly.                                                                                               1 

477 

478 

479 

480 

481 

482 

483 

484 

485 

486 

487 

I 

48 

48 

48 

48 

48 

"48 

"48 

48 

49 

49 

49 

I 

3 

f. 

96 

96 

96 

96 

96 

97 

97 

97 

97 

97 

3 

3 

i43 

143 

144 

1 44 

144 

i45 

145 

145 

1 46 

1 46 

1 46 

3 

4 

19' 

■9' 

192 

192 

192 

193 

193 

194 

194 

194 

iq5 

4 

5 

23q 

239 

240 

240 

241 

34 1 

342 

242 

243 

243 

244 

5 

6 

386 

3S7 

287 

288 

289 

289 

290 

290 

291 

292 

292 

6 

7 

334 

335 

335 

336 

337 

337 

338 

339 

340 

340 

341 

7 

8 

382 

382 

383 

384 

385 

386 

386 

387 

388 

389 

3qo 

8 

9 

429 

43o 

43i 

432 

433   1 

434 

4 

35 

4: 

6 

43 

7 

437 

438 

9 

TABLE  II.  —  To  find  the  time  7";  tlie  sum  of  the  radii  r-\-r  ",  and  the  chord  c  being  given. 


Siun  01'  the  Radii  r-f-r 


Chord 
C. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

0,0") 
,u6 
0,1)7 
o.oy 


(), 


0,10 
0,11 
0,12 
û,i3 
o,i4 

0,1'j 
0,16 
0,77 

0,I(J 

0,30 
0,21 
0,22 
0,23 
0,24 

0,23 
0,26 
0,27 
0,28 
0,29 

o,3t) 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 
1,00 


2,81 


Days  (liir. 


o,oou 

0,487 
0,974 
1,462 
1,949 

2,436 
2,923 
3.41 1 
3,898 
4,385 

4.8-2 
5,359 
5,84'"i 
6.334 
6,821 

7,3o8 
-,7o5 
8,282 
8,-69 

9.256 

9.743 

io,2  3o 
10,716 

II,2o3 

1 1 ,690 

12,177 
12,664 
i3,i5o 
1 3,637 
14,124 

i4,6io 
1 5,09' 
1 5,583 
16.070 
i6;556 

17,042 
17,529 
i8,oi5 
i8,5oi 
18,987 

19,473 
i9!959 
20,445 
20,93 1 
2i,4i6 

21,90: 

24,33o 

26,755 

29, 1 78 

31,599 

34,017 

36,433 
38,845 
4i,255 
43,660 
46,062 
48,460 


iS 


2,82 


Uays  |<lif^ 

0,000 

0,488 

0,976 

1,464 

1,952 

2,440 
3.929 
3,417 
3,9o5 
4,393 


3,9481 


4,881 

5,3('>9 
5.85- 
6,345 
6,833 

-,32I 

7,809 
8.29" 
8,-84 
9,272 

9,-60 
[0,248 
10,736 

11,223 
11,711 

12,199 

12.686 
l3,i74 
1 3,66 1 
i4,i49 

i4,636 
i5,i24 
1 5,6 
16,098 
i6,585 

17,073 
i7,56o 
18,047 
18,534 
19,021 

19,508 

I9'995 
20,481 
20,968 
21,455 

21,941 
24,3-3 
26,803 
2g.23i 
3 1 ',656 
34,079 

36,4' 

38,915 

41,329 

43,739 

46,i46 

48,548 


21 

23 
23 
25 
20 

36 
26 
28 
29 

3o 

3o 
3 

32 

33 
34 

34 
35 
37 

37 

38 

3q 
43 
48 

52 

56 
61 

66 

70 

74 

79 
83 


2,83 


Days  \dit'. 


3,9762 


0,000 
0,489 
0,9-8 
1 ,467 
1,956 

2,445 
2,934 
3,423 

3.t)12 

4,4oi 

4,889 
5,378 
5,867 
6,356 
6,845 

7,334 
7,822 
8,3 1 1 
8,800 
9,289 

9 

10,26*) 
10,755 
11,243 
11,732 

12,220 
13,709 
13,197 
1 3,686 
14,174 

14,663 
i5,i5o 
1 5,639 
16,137 
i6,6i5 

i7,io3 

17,591 
18,079 
18,567 
19,055 

19,543 
20,o3o 
20,5i8 
2 1  ,oo5 
21,493 

21.980 
24,4'6 
26,85i 
29,283 
3i,7i2 
34,i4o 

36,564 
38,q85 
4i,4o3 
43,818 
46,229 
48,636 


2,84 


Days  jdil'. 


0,000 
o,4go 
0,980 
1,470 
1,959 

2,449 

2,939 
3,429 

3,9Iq 
4,408 

4,898 
5,388 
5,878 
6,36- 
6,857 

7,347 

7,836 

8,326 

8,81 

9,3o5 

9,795 
10,284 
10,774 
11,263 
11,752 

12,243 
I2,73i 

l3,220 

1 3,710 
14,199 

1 4,688 
r5.i7 
1 5,666 
16, 1 55 
16,64. 

I7,i33 
17,633 
18,111 
18,600 


19,088    34 


4,0045 


19,57' 
20,066 
20,554 
21,043 
2 1,53 1 

22,019 
34,460 
26,898 
29,335 
3 1 ,769 
34,200 

36,629 

39.055 

41,478 

43,897 

46,3 

48,724 


2,85 


Days  I  dit'. 


4,0328 


0,000 
0,491 
0,981 
1,472 
1 ,963 

2,453 
2.944 
3,435 
3,925 
4,416 

4,907 
5,397 

5,888 
6,3-8 
6,869 

7,36o 
7,85o 
8,341 
8,83 1 
9,321 

9,812 

lO,302 

10,793 
11,283 
11,773 

12,263 
12,754 
i3,244 
i3,-34 

l4,234 

14.-^14 
1 5,204 
1 5,6(), 
16,184 
16,674 

17,163 
n,653 
i8,i43 
1 8,632 
19,1 

ig,6i3 
20,101 
20,590 
3 1 .080 
21,569 

22.o58 

24,5o3 
36,946 
29,387 
3i,825 
34,261 

36,694 
3g,i25 
4i,552 
43,975 
46,395 
48,812 


2,86 


Diiy3  |dir. 


4,0613 


0,000 
0,492 
0,983 
1,475 
1 ,966 

2,458 

2,949 
3,441 
3,932 

4:424 

4,915 

5,407 
5,898 

6,39c 

6,881 
7,372 

7,864 
8,355 
8,847 
9,338 

9,829 
10,320 
10,812 
ii,3o3 
11,794 

12,285 

12,776 
13,267 
i3,758 
14,249 

1 4,740 
i5,23i 
i5,72i 

16, 312 

16,703 

17,194 
17,684 
18,175 

i8,665 
19,156 

ig,646 
20,1 36 
20,627 
21,117 
2 1 ,607 

22,097 
24,546 
26,994 
29,439 
31,882 
34,322 

36,759 
3g,ig4 
41,626 
44,o54 
46,478 
48,899 


'9 


0,0000 
0,000 1 

o,of)o4 

o,<ioot) 
0,0016 

0,0035 

o,oo36 
o,oo4g 
0,0064 
0,008 1 

0,0100 
0,01 3 1 
0,01 44 
0,01 6g 
0,0196 

0,03  3  5 
o,o356 
0,028g 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
o,o484 
o,o52g 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

0,0900 
0,0961 
0,1024 
0,1089 
0,11 56 

0,1225 
0,1 396 
0,1 36g 
0,1444 

0,l521 

0,1600 
0,1681 
0,1764 
o,i84g 
o,ig36 

0,3025 

0,2  5oo 
o,3o25 
0,3600 
0,4225 
o,4goo 

0,5625 
0,6400 
0,7225 
0,8100 
0,9025 
,0000 


Prop,  parts  for  tho  fioiii  of  tho  Kadii. 
1  I  2   I   3  I  4  I    5  I   6  I   7  I  8  I  9 


4,0898 


(r  -i-  r")^  or  r^  4"  '"  "  ^  nearly. 


485 

486 

487 

488 

48g 

490 

491 

49 

49 

49 

49 

49 

49 

49 

97 

97 

97 

98 

98 

98 

98 

i46 

i46 

i46 

i46 

i47 

1 47 

l47 

194 

194 

195 

195 

196 

196 

196 

243 

243 

244 

244 

245 

245 

246 

291 

292 

292 

2g3 

293 

294 

2g5 

340 

340 

341 

342 

342 

343 

344 

388 

389 

390 

3qo 

391 

392 

393 

437 

437 

438 

439 

44o 

44 1 

443 

492 


148 
197 
246 

295 

344 
394 
443 


10 


8 
9 
9 
10  II 


22  26 


20  23 


5 
5 
6 

7 
8 

9 
10 
11 
12 
i3 

i4 
i4 
i5 
16 

17 


'9 
20 
21 
22 

33 
23 

24 

25 

26 

27 
28 

29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 
4o 

4i 
4i 
42 
43 
44 

45 
46 
47 
48 

49 

5o 

5o 
5i 

52 

53 

54 
55 
56 
57 
58 

59 
59 
60 
61 
62 

63 
72 
81 
90 


TABLE  ir 

. —  Tofinil  the  time  T 

;  the  sura  of  the  radii 

r  +  r", 

ant 

the  chord 

c  being 

given. 

Sum  of  tlie  Raiiii  r  -j-  r".                                                                                                            1 

Chord 

c. 

2,87 

2,88 

2,89 

2,90 

2,91 

2,92 

2,93 

2,94 

2,95 

2,96 

Days  Idif. 

Diiys  Idif. 

D.iy8  Irlif. 

Days  |dif. 

Days  IdiC. 

Days  |dif. 

Days  |dir. 

Days  Idit". 

Days  |dif. 

Days  {dir. 

0,00 
0,01 
0,02 
o,o3 
o,o4 

0,000 
0,493 
0,985 

1,477 
1,970 

I 
2 
3 
3 

0,000 
0,493 

o,9«7 
1,480 
1 ,973 

I 
I 
2 

3 

0,000 

0,494 
0,988 
1,482 
1,976 

I 
2 

3 
4 

0,000 
0,495 
0,990 
1,485 
1,980 

I 
3 
2 

3 

0,000 
0,496 
0,993 
1,487 
1,983 

1 

3 
4 

O,ùù0 
0,497 
0,993 
1,490 
1,987 

I 
2 

3 
3 

0,000 
0,498 
0,995 
1,493 
1,990 

0 
2 
2 

4 

0,000 
0,498 
0,997 
1,495 
1,994 

I 
I 

3 
3 

0,000 

o,4gg 

0,990 

i,4g8 
■,997 

1 

3 
2 
3 

0,000 
o,5oo 
1,000 
i,5oo 
2,000 

I 
2 

3 

4 

0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

o,o5 
0,06 
0,07 
0,08 
0,09 

2,462 
2,954 
3,447 

3,939 

4,432 

4 
6 
6 

7 
7 

2,466 
2,960 
3,453 
3,946 
4,439 

5 
5 
6 

7 
8 

2,471 
2.965 

3:459 
3.953 

4,447 

4 
5 
() 
7 
8 

2,475 
3,970 
3,465 
3, 960 
4,455 

4 
5 
6 

7 
7 

2,479 
2.975 
3,471 
3,967 
4,462 

4 
5 
6 
6 
8 

2,483 
3, 980 
3,477 
3,973 
4,470 

5 
5 
6 

7 
8 

2,488 
2,985 
3,483 
3,980 
4,478 

4 
5 

6 

7 
7 

2,492 
2,990 
3,489 
3,987 
4,485 

4 
5 
5 
7 
8 

2,496 
2,995 
3,494 
3,994 
4,4g3 

4 
5 
6 
6 

7 

2,5oo 
3,000 
3,5oo 
4,000 
4,5oo 

5 
5 
6 

7 
8 

0,0025 

ù,oo36 
0,0049 
0,0064 
0,0081 

0,10 
0,1 1 
0,12 
0,1 3 
0,1 4 

4,924 
5,4i6 

5,909 
6,4oi 
6,893 

8 
10 
10 
II 
12 

4.933 
5,426 
5,919 
6,4 1 2 
6,905 

9 

9 

10 

II 

12 

4.941 
5,435 
5,929 
6,423 
6,917 

9 
9 
10 
II 
12 

4,95o 
5,444 
5,939 
6,434 
6,929 

8 
10 
II 
11 
12 

4,958 
5,454 
5,950 
6,445 
6,941 

9 
9 
10 
11 
12 

4,967 
5,463 
5,g6o 
6,456 
6,953 

8 
10 
10 
II 
12 

4,975 
5,473 
5,970 
6,467 
6,965 

9 
9 
10 
11 

13 

4,984 
5,482 
5,980 
6,478 
6,977 

8 

9 
10 
11 

13 

4,gg2 
5,4gi 
5,ggo 
6,489 
6,989 

8 

9 
10 
1 1 
1 1 

5,000 
5,5oo 
6,000 
6,5oo 
7,000 

9 
10 
1 1 
11 
12 

0,0100 
0,0121 
0,0 1 44 
0,0169 
0,0196 

0,1 5 
0,16 
0,17 
0,18 
0,19 

7,385 
7,878 
8,370 
8,863 
9,354 

i3 
i3 
i4 
i5 
16 

7,398 
7,891 
8,384 
8,877 
9,370 

i3 

i4 
i5 
16 

17 

7,4  n 
7,905 
8,399 
8,893 
9,387 

1 3 
i4 
i4 
i5 
16 

7.434 

7.919 
8,4i3 
8.908 
9,4o3 

i3 
i3 
i5 
16 
16 

7,437 
7,932 
8,428 
8,934 
9,419 

12 
i4 
i4 
i5 
16 

7,449 
7,946 
8,443 
8,939 
9,435 

1 3 
i4 
i5 
i5 
16 

7,462 
7,960 
8,457 
8,954 
9,45i 

i3 
i3 
i4 
i5 
17 

7,475 
7,973 
8,471 
8,96g 
9,468 

i3 
i4 
i5 
16 
16 

7,488 

7,987 
8,486 
8,985 
9,484 

12 
i3 
14 
i5 
16 

7,5oo 
8,000 
8,5oo 
9,000 
9,5oo 

i3 
i4 
i4 
i5 
16 

0,0225 
0,02 56 
0,0289 
0,0824 
o,o36i 

0,20 
0,21 
0,22 

0,23 

0,24 

9,846 
io,338 
10,8  3o 

11,322 

11,814 

17 
18 

19 
20 
21 

9,863 
io,356 
10,849 
11,34? 
11,835 

18 
18 

'9 

20 

31 

9,88. 
10,374 
10,868 
11,362 
1 1 ,856 

17 
18 

19 
20 
30 

9,898 
10,393 
10,887 
1 1 ,383 
1 1 ,876 

17 
18 

19 
19 
21 

9.915 
io,4io 
10,906 
1 1, 401 
11,897 

17 
18 
18 
20 
20 

9,932 
10,428 
10,924 
1 1 ,43 1 
11,917 

17 
18 

19 
19 
20 

9,949 
(0,446 
10,943 
1 1 ,44o 
11,937 

17 
18 

19 
20 

31 

9,966 
10,46^ 
10,962 
1 1 ,460 
ii,g58 

17 
18 
18 

19 
20 

9.983 
10,482 
10,980 

11,479 
11,978 

17 
17 

19 
20 

2f 

10,000 
10,499 
10,999 
11,499 
1 1 ,998 

16 
i& 
19 
19 
21 

o,o4oo 
0,044 1 
o,o484 
o,o52g 
0,0576 

0,25 
0,26 
0,27 
0,28 
0,29 

i2,3o6 
12,798 
13,290 
13,782 
14,274 

22 

23 
23 

24 

35 

12,338 
13,821 
1 3,3 1 3 
1 3,806 
14,399 

21 
22 
24 
34 
25 

12,349 
i3,84'3 
1 3,337 
i3,83o 
1 4,324 

33 
22 
33 

24 
34 

13,371 
13,865 
i3,36o 
13.854 
14,348 

31 

33 
33 
24 
25 

13,393 
13,887 
13.383 
13,878 
14,373 

21 

22 

23 

24 

25 

I3,4i3 
12,909 
I 3, 406 
13,903 
i4,3g8 

22 

23 
23 

24 

25 

12,435 
12,933 
13,429 
13,926 
i4,423 

31 
32 
3  3 
23 

24 

12,456 
12,954 
1 3,452 
13,949 

1 4,447 

21 
22 
22 
24 

25 

'2,477 
12,976 
1 3,474 
13,973 
14,472 

21 
22 
23 
24 
24 

12,498 
12,998 
1 3,497 
1 3,997 
14,496 

21 
22 

23 

24 

25 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

o,3o 
0,3 1 

0,32 

0,33 
0,34 

14,766 
1 5,257 
1 5,749 
16,241 
16,732 

25 

27 
27 
28 
29 

14,791 
1 5,284 
15,776 
16,369 
16,761 

26 

27 
28 
28 

3u 

14,817 
i5,3ii 
1 5,804 
16,297 
16,791 

26 

36 

27 
38 

29 

14,843 
1 5,337 
1 5,83 1 
16,335 
16,830 

25 

27 
28 

29 
29 

14,868 
1 5,364 
1 5,859 
16,354 
16,849 

26 
26 

27 
28 

29 

14,894 
15,390 
1 5,886 
i6,383 
16,878 

25 

26 

27 
28 
29 

14.919 
i5,4i6 
i5,9i3 
i6,4io 
16,907 

36 

27 
27 
28 
28 

14,945 
1 5,443 
1 5,g4o 
i6,438 
16,935 

25 

26 

27 
28 

29 

14.Q70 
15,469 
15,967 
16,466 
1(5,964 

26 
26 
28 
28 
29 

14,996 
15,495 
15,995 
16,494 
16,993 

25 

26 

27 
28 
29 

0,0900 
0,0961 
0,1034 
0,1089 
0,1 156 

0,35 
o,36 
0,37 
0,38 
o.Sg 

17,224 
17,715 
18,207 
18,698 
19,189 

3o 
3i 
3 1 
33 
34 

17,^54 

17.746 

i8,238 
i8,73i 
19,223 

3o 
3i 

33 
32 

33 

17,284 
17,777 
18,270 
18,763 
19,256 

3o 
3 1 

32 

33 
34 

i7,3i4 
17,808 
i8,3o3 
18,796 
19,290 

3o 
3i 
3 1 

32 

33 

17,344 
17,839 
18,333 
18,828 
19,323 

3o 

32 

33 
33 

17,373 
i7,86q 
i8,365 
1 8,861 
ig,356 

3o 
3i 
3i 

32 

33 

i7,4o3 
17,900 
18,396 
18,893 
19,389 

3o 
3o 

32 
32 

34 

17,433 
17,930 
18.428 
18,925 
19,423 

3o 
3i 
3i 
33 
33 

17,463 
17,961 
18,459 
18,958 
19,456 

=9 
3i 

32 
32 

33 

17,492 
17,992 
18,491 
18.990 
19,489 

3o 
3o 
3i 

32 

33 

0,1225 
0, 1 296 
0, 1 36g 
o,i444 

0,l52I 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

19,680 
20,172 
20.663 
2i,i54 
21,645 

35 
35 
36 

37 
38 

19,715 
20,207 
20,699 
21. 191 
31,683 

34 
35 
36 
37 
37 

19:749 

20,343 
20,735 
21,238 
31,720 

34 
35 
36 

37 
38 

19,783 
20,377 
20,771 
21,265 
21,758 

35 
35 
36 
36 
38 

19,818 
20,3 1 2 
20,807 

2I,30I 

21,796 

34 
35 
36 

37 
37 

19,853 
20.347 
20,843 
2  1,338 
21,833 

34 
35 
35 

37 
38 

19,886 
20,382 
20.878 
21,375 
21,871 

34 
35 
36 
36 

37 

19,920 
20,417 
2o,gi4 

2I,4lI 

2 1 ,908 

34 
35 
36 

37 
38 

19,954 
20,453 
20.950 
31,448 
2 1 ,946 

34 
35 
35 
36 

37 

19,988 
20,487 
20,985 
21,484 
21,983 

34 
34 
36 

37 
37 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,45 
o,5o 
0,55 
0,60 
0,65 
0,70 

22,l36 

24,589 
27,041 
29.490 
3 1, 938 
34,382 

38 
43 
47 

52 

56 
61 

32,174 
24,632 
27,088 
29,542 
3 1, 994 
34,443 

39 
43 
48 

52 

56 
60 

23,2l3 
24,675 

27,1 36 
29,594 
33,o5o 
34,5o3 

39 

An 
5i 
56 
60 

22,252 
24,718 
27,183 
29,645 
32,106 

34,563 

38 

43 
47 

53 

55 
61 

22,290 
34.761 

37,33o 

39,697 
32,161 
34,624 

47 
5i 
56 
60 

23,329 

24,804 
27,277 
29,748 
32,217 
34,684 

38 
42 
47 
5i 
56 
60 

32.367 
24,846 
27,324 

29,799 
32,273 

34,744 

38 
43 

47 

53 

55 
59 

22,4o5 

24,889 
27,371 
2g,85i 
32,328 
34,8o3 

38 
42 
47 
5i 
56 
60 

33,443 
34,981 
27,418 
29,902 
32,384 
34,863 

46 
5i 
55 
60 

22,482 

24,974 
27,464 
29,953 
32,439 
34,923 

38 
42 
47 
5i 
55 
59 

0,2025 

o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,75 
0,80 
o,85 
0,90 
0,95 
1,00 

36,82  4 
39,264 
41,699 
44,1 32 
46,56 1 
48,986 

65 

69 
74 
78 
83 
87 

36,889 
39,333 
41,773 
44,210 
46,644 
49,073 

65 
69 

74 
78 
82 
87 

36,954 
39,403 
41^847 
44,288 
46,726 
49,160 

65 

% 

78 
82 
87 

37,019 
39,471 
41.920 
44,366 
46,808 
49.247 

64 

78 
83 
87 

37,083 

39,540 
41,993 

44,444 
46,890 
49,334 

65 

69 

74 
77 
83 
86 

37,148 
89,609 
43,067 
44,521 
46,973 
49,420 

64 
68 
73 
78 
81 
86 

37,212 
39,677 
43,140 
44,599 
47,o54 
49,506 

64 
69 
72 
77 
82 
86 

37,276 
39,746 
42,212 
44,676 
47,1 36 
49,592 

64 
68 
73 
77 
82 
86 

37,340 
39,814 
43,385 
44,753 
47,218 
49,678 

64 
68 
73 
77 
81 
86 

37,4o4 
39,882 
42,358 
44,83o 
47,299 
49,764 

64 
69 

72 
77 
81 
86 

0.5625 
0,6400 
0,7235 
0,8100 
o,go35 
1 ,0000 

4,1185 

4,1472 

4,1761 

4,2050 

4,2341 

4,2632 

4,2925 

4,3218 

4,3513  1 

4,3808  1 

â 

^   .   (r  -f-  r")^     or     t^  -\-  r""^     nearly. 


491 

492 

493 

494 

4g5 

496 

497 

498 

499 

5oo 

I 

49 

49 

49 

49 

5o 

5o 

5o 

5o 

5o 

5o 

I 

3 

98 

98 

99 

99 

99 

99 

99 

100 

100 

100 

3 

3 

i47 

i48 

l48 

i48 

149 

i4g 

149 

i5o 

i5o 

3 

4 

196 

197 

197 

198 

198 

199 

199 

200 

200 

4 

5 

246 

346 

247 

247 

248 

248 

249 

249 

25o 

25o 

5 

6 

295 

395 

3q5 

296 

297 

298 

398 

299 

299 

3oo 

6 

7 

344 

344 

345 

346 

347 

347 

348 

349 

349 

35o 

7 

8 

393 

394 

3g4 

395 

396 

397 

398 

398 

399 

400 

8 

9 

442 

443 

iA'i 

445 

446 

446 

447 

448 

44g 

45o 

9 

TABLE  II.  —  To  finil  the  time  T;  the  sum  of  the  radii  r-\-r",  and  llie  chord  c  beiiiK  given. 


Sum  of  the  Railii  r-f-r".                             j 

Clioiil 
C. 

2,97 

2,98 

nays  iiiir. 

2,99 

3,00 

3,01 

3,02 

Days  |dif. 

Days  Idil". 

Days  |ciif. 

Days  lilif. 

Days  |.iif. 

0,00 

o,ouo 

0,000 

0,000 

0,000 

0,000 

0,000 

o,ouoo 

0,01 

o,5oi 

1 

0,502 

I 

o,5o3 

0 

o,5o3 

1 

o,5o4 

1 

o,5o5 

I 

0,0001 

0,02 

1,002 

u 

i,oo4 

1 

i,oo5 

2 

1,007 

2 

1,009 

1 

1,010 

2 

0,0004 

o,o3 

i,5o3 

2 

i,5o5 

3 

i,5o8 

2 

i,5io 

3 

i,5i3 

2 

i,5i5 

3 

o,ooog 

o,o4 

2,oo4 

3 

2,007 

3 

2,010 

4 

2,014 

3 

2,017 

3 

2,020 

4 

0,0016 

o,o5 

2,5o5 

4 

3,509 

4 

2,5i3 

4 

2,5i7 

4 

2,521 

5 

2,526 

4 

0,0025 

o,o(5 

3,oo5 

6 

3,011 

5 

3,016 

5 

3.021 

5 

3,026 

5 

3,o3i 

5 

o,oo36 

0,07 

3,5oC 

6 

3,5i2 

6 

3,5i8 

6 

3,524 

6 

3,53o 

6 

3,536 

6 

0,0049 

0,08 

4,00-' 

7 

4,014 

7 

4.021 

6 

4,027 

7 

4,o34 

7 

4,04 1 

7 

0,0064 

0,09 

4,5o8 

8 

4,5i6 

7 

4,523 

8 

4,53i 

7 

4,538 

8 

4.546 

7 

0,0081 

0,10 

5,oog 

8 

5,017 

9 

5,026 

8 

5.o34 

9 

5,043 

8 

5,o5i 

8 

0,0100 

0,1 1 

5,5io 

9 

5,519 

9 

5,528 

ii> 

5,538 

9 

5,547 

9 

5,556 

9 

0,0121 

o,r2 

6,011 

10 

6,021 

10 

6,o3i 

10 

6,04 1 

10 

6,o5i 

10 

6,061 

10 

0,01 44 

0,1 3 

6,5ii 

II 

6,522 

11 

6,533 

1 1 

6,544 

11 

6,555 

1 1 

6,566 

1 1 

0,0169 

o,i4 

7,012 

13 

7,024 

12 

7,o36 

13 

7.048 

II 

7,059 

12 

7.071 

12 

0,0196 

0,1 5 

7,5i3 

i3 

7,526 

12 

7,538 

i3 

7,55i 

12 

7,563 

i3 

7.576 

12 

0,0225 

0,16 

8,014 

i3 

8,027 

i4 

8,04 1 

i3 

8,o54 

i4 

8,068 

i3 

8,081 

i3 

o,o256 

0,17 

8,5i4 

i5 

8,529 

i4 

8,543 

i4 

8,557 

i5 

8,572 

i4 

8,586 

14 

0,0289 

0,18 

g.oi5 

i5 

9,o3o 

i5 

9,045 

16 

g,o6i 

i5 

9,076 

i5 

9,09  ' 

i5 

o,o324 

o,ig 

9,5i6 

16 

9,532 

16 

9.548 

16 

9,564 

16 

g,58o 

16 

9,596 

16 

o,o36i 

o,ao 

10,016 

17 

io,o33 

17 

io,o5o 

17 

10,067 

17 

10,084 

16 

10,100 

17 

o,o4oo 

0,21 

10,517 

18 

10,535 

17 

10,552 

i& 

10,570 

18 

io,588 

17 

io,6o5 

18 

0,044 1 

0,22 

1 1,018 

18 

ii,o36 

'9 

11.055 

18 

1 1,073 

19 

1 1 ,092 

18 

11,110 

19 

o,o484 

0,23 

ii,5i8 

30 

11,538 

19 

11,557 

19 

11,576 

20 

1 1  ^96 

19 

1 1, 61 5 

19 

o,o52g 

0,24 

12,019 

30 

12,039 

20 

i2,o5g 

20 

12,079 

21 

12,100 

20 

I2,I30 

20 

0,0576 

0,25 

I2,5ig 

21 

i3,54o 

21 

i3,56i 

21 

13,583 

21 

iD,6o3 

21 

12,624 

21 

0,0625 

0,26 

1 3,020 

22 

13,042 

22 

1 3,064 

21 

i3,o85 

32 

i3,i07 

22 

i3,iP9 

22 

0,0676 

0,27 

i3,520 

23 

1 3,543 

23 

i3,566 

22 

1 3,588 

23 

i3,6ii 

23 

i3,634 

22 

0,0729 

0,28 

14,021 

23 

i4,o44 

24 

i4,o68 

23 

14,091 

24 

i4,ii5 

23 

i4,i38 

24 

0,0784 

0,29 

i4,52i 

24 

14.545 

25 

14,570 

24 

14,594 

24 

i4,6i8 

25 

14,643 

24 

o,o84i 

o,3o 

1 5,021 

25 

1 5.046 

26 

15,072 

25 

15,097 

25 

l5,123 

25 

i5,i47 

25 

0,0900 

o,3i 

i5,52i 

27 

1 5,548 

26 

1 5,574 

26 

1 5,600 

26 

15,626 

26 

1 5,652 

26 

0,0961 

0,32 

16,022 

37 

16,049 

27 

16,076 

26 

16,102 

27 

16.I2C) 

27 

i6,i56 

27 

0,1024 

0,33 

16,522 

28 

i6,55o 

2-! 

16,577 

38 

i6,6o5 

28 

1 6,633 

28 

16,661 

27 

0,1089 

0,34 

17,022 

=9 

i7,o5i 

28 

17,079 

29 

17,108 

28 

I7,i36 

29 

I7,i65 

28 

0,11 56 

0,35 

17,522 

29 

i7,55i 

3o 

i7,58i 

29 

17,610 

3o 

17,640 

29 

17,669 

29 

0,1225 

o,36 

18,022 

3o 

i8,o52 

3i 

i8,o83 

3o 

i8,ii3 

3o 

18,143 

3o 

18,173 

3i 

0,1296 

0,37 

18,522 

3i 

18,553 

3i 

i8,584 

3i 

i8,6i5 

32 

18,647 

3i 

18,678 

3i 

0,1369 

o,38 

19,022 

32 

19,054 

32 

19,086 

32 

19,118 

32 

ig,i5o 

32 

19,182 

32 

0,1 444 

0,39 

ig,522 

33 

19,555 

33 

19,588 

32 

1 9,620 

33 

ig,653 

33 

19,686 

32 

0,l521 

0,40 

20,022 

33 

2o,o55 

34 

20,089 

34 

20,123 

33 

30,1 56 

34 

20,190 

33 

0,1600 

0,4 1 

20,521 

35 

2o,556 

34 

2o,5go 

35 

20,625 

34 

20,659 

35 

2o,6g4 

34 

0,1681 

0,42 

2 1 ,02 1 

35 

2 1  ,o56 

36 

21,092 

35 

21,127 

35 

21,162 

36 

21,198 

35 

0,1764 

0,43 

21,521 

36 

21,557 

36 

21,593 

36 

21,629 

37 

21.666 

36 

21,702 

36 

0,1849 

0,44 

22,020 

37 

22,057 

37 

22,094 

37 

22,l3l 

37 

22;i68 

37 

22,2o5 

37 

0,1936 

0,45 

22,520 

38 

22,558 

38 

22,596 

38 

22,634 

37 

23,671 

38 

22,70g 

38 

0,2025 

o,5o 

25,016 

42 

25,o58 

43 

25,101 

43 

25,143 

42 

25,i85 

43 

25,227 

42 

o,25oo 

0,55 

27,5 11 

46 

27,557 

47 

27,604 

46 

27,65o 

47 

27,697 

46 

37,743 

46 

o,3o25 

0,60 

3o,oo4 

5o 

3o,o54 

5i 

3o,io5 

5i 

3o,i56 

5o 

3o,2o6 

5i 

3o,357 

5o 

o,36oo 

o,65 

32,494 

55 

32,549 

55 

32,6o4 

55 

32,659 

55 

32,7i4 

55 

32,76g 

54 

0,4225 

0,70 

34,982 

60 

35,042 

59 

35,101 

59 

35,160 

59 

35,2ig 

59 

35,278 

59 

0,4900 

0,75 

37,468 

63 

37,53i 

64 

37,595 

64 

37,659 

63 

37,722 

63 

37,785 

63 

0,5625 

0,80 

39.951 

68 

40,019 

68 

40,087 

67 

40, 1 54 

68 

40,222 

68 

40,290 

67 

o,64oo 

o,85 

43,430 

73 

42,5o3 

72 

42,575 

72 

42,647 

72 

42,71g 

72 

42,791 

72 

0,7225 

0,90 

44,907 

77 

44,984 

76 

45.060 

77 

45,i37 

76 

45,2i3 

76 

45,289 

76 

0,8100 

0,95 

47,380 

81 

47,461 

81 

47.542 

81 

47,623 

81 

47,704 

80 

47,784 

81 

0,9025 

1,00 

49,85o 

85 

49,935 

86 

50,02  1 

85 

5o,io6 

85 

50,191 

85 

50,276 

85 

1 ,0000 

1  4,4105 

4,4402 

4,4701 

4,5000 

4,5301 

4,5602 

i.(r+r"J=  or  r'-f-r'"  nearly.                      | 

499 

5oo 

5oi 

502 

5o3 

5o4 

5o5 

5(,6 

5o 

5o 

5o 

5o 

5o 

5o 

5i 

5i 

100 

100 

100 

100 

101 

lOI 

101 

101 

i5o 

i5o 

i5o 

i5i 

i5i 

i5i 

l52 

l52 

200 

200 

200 

201 

201 

202 

202 

202 

25o 

25o 

25l 

25l 

252 

252 

253 

253 

209 

3oo 

3oi 

3oi 

302 

303 

3o3 

3o4 

34q 

35o 

35i 

35i 

352 

353 

354 

354 

3qq 

400 

4oi 

402 

402 

4o3 

4o4 

4o5 

449 

45o 

45i 

452 

453 

454 

455 

455 

Prup.  purts  I'or  tlio  sum  of  tho  Radii. 

I  |3|3|4  |5|6|7|8|9 


60 
61 
6? 
63 
64 

65 
66 
67 
68 

69 

70 
80 

90 

100 


23 
23 

24 

25 

26 

27 
28 
29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 
40 

4i 
4i 
42 
43 
44 

45 
46 
47 
48 

49 

5o 
5o 
5i 

52 

53 

54 
55 
56 

57 
58 

59 
59 
60 
61 
62 

63 

72 
81 
90 


a12 


TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-f»'",  and  the  chord  c  heing  p;iven. 


Sum  of  tlie  Iladil  r-\~r' 


Chord 

c. 


0,00 
0,01 
0,02 
o,o3 
o,( 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
o,i3 
o,i4 

o,i5 
o,i6 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,38 
0,29 

o,3o 
0,3 1 

0,32 

0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
0,39 

o,4o 
o,4i 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
0,65 
0,70 

0,75 
0,80 
0,85 
o,go 
o,()5 


3,03 


Days  |dif. 


0,000 
O,5o6 
1,012 

i,5i8 
2,024 

2,53o 
3,o36 
3,542 
4,o48 
4,553 

5,059 
5,565 
6,071 
6,577 
7,o83 

7,588 
8,094 
8,600 
9,106 
9,612 

10,117 
10,623 
11,129 
11,634 
12,140 

12,645 
i3,i5i 
1 3,656 
14,162 
14,667 

15,172 
15,678 
i6,i83 
16,688 
I7>i93 

1 7,698 
18,204 
18,709 
19,214 
19,718 

20,223 
20.728 

21,233 

31,738 
23,342 

22,747 
25,269 
27,789 
3o,3o7 
32,823 
35,337 

37,848 
40,357 
42,863 
45,365 
47,865 
5o,36i 

4,5905 


3,04 


Days  |dit'. 


0,0( 
0,507 

i,oi4 
1,520 

2,037 
2,534 

3,o4i 

3,547 
4,o54 
4,56i 

5,068 
5,574 
6,081 
6,588 
7.094 

7,601 
8,108 
8,6i4 
9,121 
9,637 

10,1 34 
io,64i' 
11,147 

11;653 

12,160 

12,666 
13,172 
13,679 
i4,i85 
14,691 

15,197 
1 5,704 
16,210 
16,716 
17,322 

17,798 
18,234 
18,739 
19,245 
19,751 

30,257 
30,762 
21,268 
21,774 
22,279 

22,784 
25, 3i  1 
37,835 
30,35? 
32.878 
35,3g6 

37,911 
0,424 
42,934 
45,441 
47,94'i 
5o,445 


3,05 


Daysldil'. 


4,6208 


0,000 
o,5o8 
1, 01 5 
1,533 
2,o3o 

2,538 
3,046 
3,553 
4,061 
4,568 

5,076 
5,584 
6,091 
6,599 
7,106 

7,614 

8,131 

8,628 
9,1 36 
9,643 

io,i5i 
10,658 
ii,i65 
11,6' 

12,l8o 

12,687 
13,194 
1 3,701 
i4,2o8 
i4,7i5 

l5,223 

15,739 

16, 2 36 

16,743 

17,250 

I7>757 
18,264 
18,770 
I9>277 
19,784 

20,290 
20,797 
2i,3o3 
2 1 ,809 

22,3l6 

22,833 
25,353 
27,881 
3o,4o8 
33,933 
35,455 

37,974 
40,492 
43,006 

45,517 
48,025 
5o,53o 


3,06 

Days  Idif. 


4,6513 


0,000 
o,5o8 
1,017 
1,525 
2,o34 

2,542 
3,o5i 
3,559 
4,067 
4,576 

5,084 
5,593 
6,101 
6,609 
7,118 

7,626 
8,i34 
8,643 
9,i5i 
9.659 

10,167 
10,675 
1 1 , 1 84 
1 1 ,692 


12,708 
i3,2i6 
1 3,724 

l4,232 

1 4,740 

1 5,247 

1 5,755 

i6,263 
16,771 
17,278 

17,786 
18,294 
18,801 
19,309 
19,816 

30,324 
20,83i 
31,338 
21,845 

22,352 


3,07 


Days[dif. 


3,08 


0,000 
0,509 
1,019 
1,528 

2,o37 

3,546 
3,o56 
3,565 
4,074 
4,583 

5,093 
5,602 
6,111 
6,620 
7,129 

7,638 
8, 1 48 
8,657 
9,166 
9,675 

10,184 
10,693 
11,202 


,86o|  37 
25,394 
37,937 
3o,458 
32,987 
35,5i3 


38,o37 
0,559 
43,077 
45,593 
48,io5 
5o,6i4 

4,6818 


19,729 
13,237 

1 3,746 
i4,255 
14,764 

15,372 
15,781 
16,290 
16,798 
i7,3o7 

i7,8i5 
18,324 
i8,S32 
19,340 
19,849 

30,357 
30,865 
21,373 
21,881 
23,389 

23,897 
25,436 
27,973 
3o,5o8 
33,o4i 
35,573 

38,100 
40,626 
43,149 
45,668 
48,i85 
50,6981 


Days  |dir. 


4,7125 


0,000 
0,5 10 
1,020 

i,53o 
2,o4o 

2,55i 
3,061 
3,571 
4,081 
4,591 

5,101 
5,611 
6,121 
6,63 1 
7>i4i 

7,65 1 
8,161 
8,671 
9,181 
9,691 

10,300 
10,710 
11,220 

1 1 ,73o 
12,240 

",749 

i3,359 
13,769 
14,278 
14,788 

1 5,297 
1 5,807 
i6,3i6 
16,826 
17,335 

17,844 
18,353 
i8,863 
19,372 
19,881 

20,3go 
20,899 
2 1 ,4oS 
21,917 
22,426 

22,934 
25,477 
28,019 
3o,558 
33,095 
35,63o 

38,i63 
40,693 
43,220 
45,744 
48,265 
50,782! 


3,09 


Days  Idif. 


0,000 
o,5i  1 
1,022 
1,533 
2,o44 

2,555 
3,066 

3,577 
4,087 
4,598 

5,109 
5,620 
6,i3i 
6,642 
7,i53 

7,663 
8,174 
8,685 

9,196 
9,706 


4,7432 


10,728 

11,238 
11,749 

13,359 

12,770 
1 3,280 
13,791 
i4,3oi 
i4,8i2 

l5,322 

i5,832 
16,343 
i6,853 
17,363 

17,873 
i8,383 
18,893 
19,403 
19,913 

20,423 
20,933 
21,443 
31,953 
22,462 

22,972 
25,519 
28,064 
3o,6o8 
33,i49 
35,688 

38,335 
40,759 
43.291 
45^819 
■",344 
5o,866 


23 


3,10 


Days  Idir. 


4,7741 


0,000 

0,5l2 

1,034 
1,535 
2,047 

2,559 
3,071 
3;582 
4,094 
4,606 

5,117 
5,639 
6,i4i 
6,652 
7,164 

7,676 
8,187 
8,699 
9,210 
9,733 

10,233 
10.745 
11,256 
11,768 
12,27g 

12,791 
j3,3o2 
i3,8i3 
14,324 
i4,836 

1 5,347 
1 5,858 
16,369 
16,880 


17,391    28 


17.903 
i8,4i3 
18,924 
19,435 
19,946 

20,4  56 
20,967 
21,478 
21,988 
22,499 

23,009 
25,56o 
38,110 
3o,657 
33,3o3 
35,747 

38,288 
40.826 
43,362 
45,894 
48,424 
5o,95o  83 


3,11 


Days  |dif. 


0,000 
0,5 1 3 
1,025 
1,538 
2,o5o 

2,563 
3,075 
3,588 
4,101 
4,61 3 

5,126 
5,638 
6,1 5 1 
6,663 
7,176 

7,688 
8,201 
8,71 3 
9,225 
9,738 

10,25o 

10,762 
11,275 
1 1 ,787 
'2,299 

12,8 

i3,323 
1 3,836 
14,348 
14,860 


15,373    24 
1 5,884 
16,396 
16,907 


3,12 


Dav! 


4,8050 


'7,419 

17,931 
18,443 
18,955 
19,466 

19:978 


31,001 
2I,5l2 
22,024 

22,535 

23,046 
25,602 

28,155 

30,707 

33,257 

35,8o5 

38,35o 
40,893 
43,432 
45,969 
48,5o3 
5i.o33 


0,000 
o,5i3 
1.027 
1, 540 
2,o54 

2,567 

3,080 

3,59. 

4,107 

4,621 

5,i34 
5,647 
6,161 
6,674 
7,187 

7,700 
8,2 

8,727 
9,240 
9,753 

10,266 
10,780 
1 1,393 
11,806 
12,319 

12,832 

1 3,345 

1 3,858 
14,371 


15,396 
1 5;909 
16,422 
16,935 
17,447 

17.960 
18^473 
18,985 
19,498 
20,010 

20,522 
3i,o35 
21,547 
33,o5g 
22,571 

33,o83 
35,643 
38,201 
3o,757 
33,3ii 
35,863 

38,4i2 
4o,g5g 
43,5o3 
46,044 
48,582 
5i,ii7 


37  0,1936 


4,8361  I  4,8672 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 

o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 

0,013  1 

0,01 44 
0,0169 
0,0196 

0,0225 
0,0256 
0,028g 
0,0824 
o,o36 1 

o,o4oo 
0,044 1 
o,o484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0739 
0,0784 
0,08 

0,0900 
0,0961 
0,1024 
0,1c 
0,1 1 56 

0,1225 
0,1296 
0,1369 
0,1444 
0,1 52  I 

1600 
0,1681 
0,1764 
0,1849 


0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 

IF 


.  (r  -{-  r")'     or    r'^  -^  r  "  ^    nearly. 


5o4 

5o5 

5o6 

5o7 

5o8 

5o 

5i 

5i 

5i 

5i 

101 

101 

101 

101 

102 

i5i 

l52 

l52 

l52 

l52 

202 

202 

3f)2 

303 

2o3 

252 

253 

253 

2,54 

254 

3o2 

3o3 

3o4 

3o4 

3o5 

353 

354 

354 

355 

356 

40  3 

4o4 

4o5 

4o6 

4o6 

454 

455 

455 

456 

457 

Sog 

5io 

5ii 

5i 

5i 

5i 

102 

102 

102 

1 53 

i53 

i53 

204 

204 

204 

255 

355 

2  56 

3o5 

3o6 

3o7 

356 

357 

358 

407 

408 

409 

458 

459 

460 

5l3 


5 1 
102 
1 54 
3o5 
356 
307 
358 
4io 
46 1 


5i3 


5i 
io3 
1 54 

205 

257 

3o8 
359 
4io 
462 


5i4 


5i 
io3 
1 54 
206 
257 
3o8 
36o 
4ii 
463 


TABI.K   II.  —  To  find  llie  time  T\  tlie  sum  of  the  radii  r-\-r",  and  the  chord  c  being  given. 


TABLE 

II. 

—  To  find  the  time 

T; 

the  sum  of  the  radii  t 

+  r". 

ind  the  chord  c 

being  given. 

Suni  of  the  Radii  r  -\-r".                                                                                                           I 

Chord 

c. 

3,19 

3,20 

3,21 

3,22    1 

3,23 

3,24 

3,25 

3,26 

3,27 

3,28 

Days  |dif. 

Days  |ilir. 

Days  |dir. 

Daysl 

dif. 

Days  |dif. 

Days  |dif. 

Days  |dif. 

Days  Idif. 

Days  |d.f. 

Days  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,5ig 

I 

0,520 

1 

0,5:  1 

I 

0,522 

0 

0,522 

I 

0,523 

I 

0,524 

1 

o,525 

I 

0,526 

0 

0,526 

I 

0,0001 

0,02 

I  ,o38 

2 

i,o4o 

2 

1,042 

I 

1,043 

2 

i,o45 

I 

i,o46 

2 

1,048 

2 

i,o5o 

I 

l,o5l 

3 

I,o53 

1 

0,0004 

o,o3 

1,557 

3 

I,56o 

2 

1,562 

3 

1,565 

2 

1,567 

3 

1,570 

2 

1,572 

2 

1,574 

3 

1,577 

2 

1,579 

3 

0,0009 

0,04 

2,077 

3 

2,080 

3 

2,o83 

3 

2,086 

4 

2, ego 

3 

2,og3 

3 

2,og6 

3 

2,099 

3 

2,102 

4 

3,106 

3 

0,0016 

o,o5 

2,596 

4 

2,600 

4 

2,6o4 

4 

2,608 

4 

2,612 

4 

2,616 

4 

2,620 

4 

2,624 

4 

2,628 

4 

3,632 

4 

0,0025 

0,06 

3,ii5 

5 

3,120 

5 

3,125 

4 

3,I2Q 

5 

3,i34 

5 

3, 139 

5 

3,144 

5 

3,i4g 

5 

3,i54 

4 

3.i58 

5 

o,oo36 

0,07 

3,634 

6 

3,64o 

5 

3,645 

6 

3,65î 

6 

3,657 

5 

3,662 

6 

3,668 

6 

3,674 

5 

3,67g 

6 

3,685 

5 

0,0049 

0,08 

4,i53 

7 

4,160 

6 

4,166 

6 

4,172 

7 

4,179 

6 

4,i85 

7 

4,192 

6 

4,1  g8 

7 

4,2o5 

6 

4,21 1 

7 

0,0064 

0,09 

4,672 

7 

4,679 

8 

4,687 

7 

4,694 

7 

4,701 

8 

4,709 

7 

4,716 

7 

4,723 

7 

4,73o 

8 

4,738 

7 

0,0081 

0,10 

5,191 

8 

5,199 

8 

5,207 

9 

5,216 

8 

5,224 

8 

5.232 

8 

5.240 

8 

5,248 

8 

5,256 

8 

5,264 

8 

0,0100 

0,1  I 

5,710 

9 

5,719 

9 

5,728 

9 

5,737 

9 

5,746 

9 

5,755 

g 

5,764 

9 

5,773 

8 

5,781 

9 

5.790 

9 

0,0121 

0,12 

6,22g 

10 

6,23g 

10 

6,249 

ID 

6,25g 

9 

6,268 

10 

6,278 

10 

6,288 

9 

6,2g7 

10 

6,3o7 

10 

6,3.7 

9 

0,01 44 

0,1 3 

6,748 

II 

6,759 

10 

6,769 

I  1 

6,780 

II 

6,791 

10 

6,801 

II 

6,812 

10 

6,822 

10 

6,832 

II 

6,843 

10 

0,0169 

o,i4 

7.267 

12 

7,279 

II 

7,290 

11 

7,3oi 

12 

7,3i3 

II 

7,324 

II 

7,335 

12 

7,347 

11 

7,358 

II 

7,369 

II 

0,0196 

0,1 5 

7,786 

i3 

7,799 

12 

7,811 

12 

7,823 

12 

7,835 

12 

7,847 

12 

7,859 

12 

7,871 

12 

7,883 

12 

7,895 

i3 

0,0225 

0,16 

8,3o5 

i3 

8,3i8 

1 3 

8,33i 

l3 

8.344 

i3 

8.357 

i3 

8,370 

i3 

8,383 

i3 

8,396 

i3 

8,4og 

i3 

8,422 

i3 

0,02  56 

0,17 

8,824 

i4 

8,838 

1 4 

8,852 

i4 

8,866 

1 3 

8,879 

i4 

8,893 

14 

8.907 

14 

8.921 

i3 

8,g34 

14 

8.948 

14 

0,0289 

0,18 

9,343 

i5 

9,358 

i5 

9,373 

i4 

9,387 

i5 

9,402 

14 

9,416 

i5 

9,43i 

i4 

9,445 

i5 

g,46o 

i4 

9.474 

i5 

o,o324 

0)i9 

9,862 

16 

9,878 

i5 

9,893 

i5 

9,908 

16 

9.924 

1 5 

9,939 

16 

9,955 

i5 

9,970 

i5 

9.985 

i5 

10,000 

16 

o,o36i 

0,20 

io,38i 

16 

10,397 

17 

1 0,4 1 4 

16 

io,43o 

16 

10,446 

16 

10,462 

16 

10,478 

16 

10,494 

17 

io,5ii 

16 

10,527 

16 

o,o4oo 

0,21 

10,900 

17 

10,917 

17 

io,g34 

17 

10,951 

17 

10,968 

17 

10,985 

17 

1 1,002 

'7 

11,0 1  g 

17 

1 1  ,o36 

17 

ii.o53 

17 

0,044 1 

0,22 

11,419 

18 

11,437 

18 

11,455 

17 

11,472 

18 

1 1 ,490 

18 

ii,5o8 

18 

11,526 

17 

11,543 

18 

ii,56i 

18 

11,570 

17 

o,o484 

0,23 

11.938 

18 

1 1  .g56 

19 

11,975 

19 

1 1  ,gg4 

18 

12.012 

19 

I2.o3l 

18 

1 2  ,o4q 

19 

12,068 

18 

12, 086 

19 

12,lo5 

iS 

0,0629 

0,24 

12,456 

20 

12,476 

19 

12,495 

20 

I2,5i5 

19 

i2;534 

20 

12,554 

19 

12,573 

19 

12,592 

20 

!2,6l2 

19 

12,63 1 

19 

0,0676 

0,25 

12,975 

20 

12,995 

21 

i3,oi6 

20 

i3,o36 

20 

i3,o56 

21 

1 3,077 

20 

13,097 

20 

i3,ii7 

20 

i3,i37 

20 

i3,i57 

20 

0,0626 

0,26 

13,494 

21 

i3,5i5 

21 

1 3,536 

21 

1 3,557 

21 

13,578 

21 

1 3,599 

21 

13,620 

21 

i3.64i 

21 

13,662 

21 

1 3,683 

21 

0,0676 

0,27 

i4,oi3 

22 

i4,o35 

21 

i4,o5(i 

22 

14,078 

22 

i4,ioo 

22 

l4,I22 

22 

i4,i44 

22 

i4,i66 

21 

14,187 

32 

14.209 

22 

0,0729 

0,28 

i4,53i 

23 

14,554 

23 

14,577 

22 

14,59g 

23 

14,622 

23 

i4,645 

22 

14,667 

23 

14,690 

23 

i4,7i3 

22 

14,735 

23 

0,0784 

0,29 

i5,o5o 

23 

15,073 

24 

15,097 

24 

l5,I2I 

23 

i5,i44 

23 

15,167 

24 

16,191 

23 

i5,2i4 

24 

1 5,238 

23 

1 5,261 

23 

0,084 1 

o,3o 

1 5,568 

25 

15,593 

24 

15.617 

25 

1 5.642 

24 

1 5,666 

24 

15,690 

24 

i5,7i4 

25 

15,739 

24 

1 5,763 

24 

15,787 

24 

0,0900 

0,3 1 

16,087 

25 

16,112 

25 

16, 1 37 

26 

i6,i63 

25 

16,188 

25 

i6,2i3 

25 

i6,238 

25 

16,263 

25 

16,288 

25 

i6.3i3 

25 

0,0961 

0,32 

i6,6o5 

27 

1 6,63  2 

26 

1 6,658 

25 

i6,683 

26 

16,709 

26 

16,735 

26 

16,761 

26 

16,787 

26 

i6,8i3 

25 

i6,838 

26 

0,1024 

0,33 

17,124 

27 

I7,i5i 

27 

17,178 

26 

17,204 

27 

I7,23i 

27 

17,258 

26 

17,284 

27 

17,311 

27 

17^338 

26 

17,364 

27 

0,1089 

0,34 

17,642 

28 

17,670 

28 

17,698 

27 

17,725 

28 

.7,753 

27 

17,780 

28 

17,808 

27 

17,835 

28 

17,863 

27 

17,890 

27 

0,1 1 56 

0,35 

18,161 

28 

18,189 

29 

18,218 

28 

18,346 

28 

18,274 

29 

i8.3o3 

28 

i8,33i 

28 

18,359 

28 

18,387 

29 

18,416 

28 

0,1226 

0,36 

18,679 

29 

18,708 

3o 

18,738 

29 

18,767 

29 

18,796 

29 

18,825 

29 

i8,854 

29 

i8,883 

29 

i8,gi2 

29 

18,941 

29 

0,1296 

0,37 

19.197 

3o 

19,227 

3i 

19,258 

3o 

19,288 

3o 

ig,3i8 

3o 

19,348 

29 

19,377 

3o 

19,407 

3o 

19,437 

3o 

19.467 

3o 

0,1369 

o,38 

19,716 

3i 

19,747 

5o 

19,777 

3i 

19,808 

3i 

19,839 

3i 

19,870 

3i 

19,901 

3o 

19,931 

3i 

19,962 

3o 

19,992 

3i 

0,1 444 

0,39 

20,234 

32 

20,266 

3i 

20,297 

32 

3o,32g 

32 

20,36i 

3i 

20,392 

32 

20,424 

3i 

20,455 

32 

20,487 

3i 

20,5 1 8 

3i 

0,1621 

o,4o 

20,752 

32 

20,784 

33 

20,817 

33 

20,85o 

32 

20,882 

3a 

20,gi4 

33 

20,947 

32 

20,979 

32 

21,011 

33 

2 1 ,043 

33 

0,1600 

o,4i 

2I,27<. 

33 

2i,3o3 

34 

21,337 

33 

21,370 

33 

2i,4o2 

34 

21,437 

33 

2 1 ,470 

33 

2i,5o3 

33 

21,536 

33 

21,569 

33 

0,1681 

0,42 

21,788 

34 

21,822 

34 

21,856 

35 

2 1 ,89 1 

3/ 

21,925 

34 

21,959 

34 

2 1 ,993 

33 

22,026 

34 

22,060 

34 

22,094 

34 

0, 1 764 

0,43 

22,3o6 

3^ 

22,341 

35 

22,376 

35 

22,4ll 

35 

2  2,446 

35 

22,481 

34 

22,5l5 

35 

22,550 

35 

23,585 

34 

22,619 

35 

0,1 84g 

0,44 

22,824 

3t 

22,860 

36 

22,896 

35 

22,931 

36 

22,967 

36 

23,oo3 

35 

23,o38 

36 

23,074 

35 

23,109 

36 

33,145 

35 

o,ig36 

0,45 

23,342 

3t 

23,378 

37 

23,4i5 

37 

23,452 

36 

23,488 

37 

23,525 

36 

23,56i 

36 

23,597 

37 

23.634 

36 

23,670 

36 

0,3025 

o,5o 

2  5,93c 

4 

25,971 

4i 

26,012 

4o 

26,052 

4i 

26,09; 

4c 

26,133 

4i 

26,174 

40 

26.214 

4i 

26,255 

4o 

26,395 

4c 

0,2600 

0,55 

28,517 

e 

28,562 

45 

28,607 

44 

28,65i 

45 

28,696 

45 

28,741 

44 

28,785 

45 

28,83o 

44 

28,874 

45 

28.91g 

44 

o,3o25 

0,60 

3 1,1 02 

4< 

3i,i5i 

4ç 

3 1, 200 

49 

31,249 

4s 

3 1, 298 

48 

3 1, 346 

49 

31.395 

48 

3 1, 443 

49 

31,492 

48 

3 1,540 

49 

o,36oo 

o,65 

33,685 

5: 

33,738 

5: 

33,7qi 

53 

33,844 

53 

33,897 

53 

33.g5c 

53 

34,oo3 

52 

34.055 

53 

34,108 

52 

34,160 

53 

0,4226 

0,70 

36,26e 

5- 

36,323 

se 

36,38 1 

57 

36,438 

57 

36,495 

5- 

36,552 

56 

36,6o8 

57 

36,665 

57 

36,72  2 

56 

36,778 

57 

0,4900 

0,75 

38,845 

61 

38 ,906 

62 

38.q68 

61 

39,02g 

61 

39,090 

61 

3g,i5i 

61 

3g.2i2 

61 

39,273 

60 

39,333 

61 

39.394 

61 

0,6626 

0,80 

41,421 

6f 

41,487 

65 

41.552 

65 

4i,6i- 

6f 

41.683 

65 

41,748 

65 

4i;8i3 

65 

41,878 

65 

4i,q43 

64 

42,007 

65 

o,64oo 

o,85 

43,994 

7c: 

44,064 

!<: 

44,i34 

6g 

44,2o3 

7r 

44,273 

6(; 

44,342 

6Ç 

44,4ii 

69 

44,48c 

69 

44,54a 

69 

44,618 

69 

0,7226 

0,90 

46,565 

lA 

46,639 

T\ 

46,71 3 

74 

46,787 

73 

46,860 

74 

46,934 

73 

47,007 

73 

47,080 

73 

47,i53 

73 

47.226 

73 

0,8100 

0,95 

4q,T33 

78 

49,21! 

It 

49,28c 

78 

49.367 

78 

49,445 

7- 

4g,522 

78 

49,600 

77 

49,677 

77 

49,754 

77 

49,83 1 

77 

0,9026 

1,00 

51,69- 

83 

51,780 

83 

51,862 

82 

5 1 ,944 

83 

52,026 

82 

52,108 

81 

52,189 

82 

52,271 

81 

52,352 

82 

52,434 

81 

1 ,0000 



5,0881 

5,1200 

5,1521 

5,18 

42 

5,21651  5,2488 

5,2813 

5,3138  1  5,3465 

5,3792 

c2 

(,■  -)-  r")'     or     r'  +  r'"'     nporly. 


5l8 
52 

io4 
i65 
207 
269 
3ii 
363 
4i4 
466 


619 

52 

io4 
1 56 
208 
260 
3ii 
363 
4i5 
467 


620 

52 

104 
1 56 
208 
260 

3l2 

364 
416 
468 


621 

62 
io4 
i56 
208 
261 
3i3 
366 
417 
469 


623 

52 

io4 

167 
209 
261 
3i3 
365 
4i8 
470 


533 

52 

io5 

167 
209 
262 
3i4 
366 
418 
471 


624 

52 

io5 
167 

3IO 
262 

3i4 
367 
4ig 
472 


626 

53 
106 
1 58 
210 
263 
3i5 
368 
420 
473 


626 

53 
106 
1 58 
210 
263 
3i6 
368 
421 
473 


627 

53 
io5 
1 58 
211 
264 
3i6 
369 
422 
474 


TABLE   II.  —  TofinJ  the  time  T;  the  sum  of  the  raJii  r-\-r'',  ami  the  chord  r.  heing  given. 


8uni  ol 

the 

Uu.lii  r+r". 

Clu.i.l 

c. 

0,00 

3,^29 

3,30 

3,31 

3,32 

3,33    3,34  1 

D.iys  l.lir. 

Uins  |dir. 

Du>s 

.lit. 

"  I)uys]iï7r. 

ll.iys  iiiir. 

Uuys  |dif  1 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

t>,00<.10 

0,01 

0,527 

1 

0,528 

1 

0,52lj 

I 

o,53o 

0 

o,53o 

1 

0,53 1 

1 

0.0001 

0,0a 

i.o54 

2 

i,o56 

2 

1  ,o5» 

I 

1 ,059 

2 

1,061 

1 

1,062 

2 

o,ooo4 

0,0  3 

1,582 

2 

1,584 

2 

1 ,58(1 

3 

1,589 

2 

1,591 

3 

..594 

a 

0,0009 

o,o4 

2,log 

3 

2,112 

3 

2,1 15 

3 

2,11b 

4 

2,122 

3 

2,125 

3 

0,0016 

0,0  5 

2,636 

4 

2,64ci 

4 

2,644 

4 

2,648 

4 

2,652 

4 

2,656 

4 

0,0025 

0,06 

3,i63 

5 

3,168 

5 

3,173 

5 

3,178 

4 

3,182 

5 

3,187 

5 

o,oo36 

0,07 

3,690 

6 

3,696 

6 

3,702 

5 

3,707 

6 

3,7.3 

5 

3,7.8 

6 

0,0049 

o,oS 

4^2]  8 

6 

4,224 

6 

4,23o 

7 

4,237 

6 

4,243 

7 

4,25o 

6 

0,0064 

0,09 

4,745 

7 

4,752 

7 

4,759 

7 

4,766 

b 

4,774 

7 

4,78. 

7 

0,0081 

0,10 

5,272 

8 

5,280 

8 

5,288 

8 

5,296 

8 

5,3o4 

8 

5,3i2 

8 

0,0100 

0,1  1 

5.799 

9 

5,808 

9 

5,817 

8 

5,825 

9 

5,834 

9 

5,843 

9 

0,01 2 1 

0,1  a 

6,326 

10 

6.336 

9 

6,345 

10 

6,355 

10 

6,365 

9 

'6,374 

10 

0,01 44 

0,1 3 

6,853 

1 1 

6,864 

10 

6,874 

lu 

6,884 

1 1 

6,895 

10 

6,go5 

1 1 

0,0169 

o,i4 

7.3SO 

12 

7,392 

1 1 

7,4o3 

11 

7,4i4 

1 1 

7,425 

1 1 

7,436 

1 1 

0,0196 

0,1 5 

-T.Q08 

1 2 

7,920 

12 

7,93' 

11 

7,943 

12 

7.955 

12 

7,967 

12 

0,0225 

0,16 

8,435 

13 

8,447 

i3 

8,460 

i3 

8,473 

i3 

8,486 

13 

8,498 

i3 

o,0256 

0,17 

8,962 

i3 

8.9-5 

i4 

8,989 

i3 

9,002 

14 

9,016 

i3 

9,"29 

i4 

0,0289 

0,1  « 

9,489 

14 

9,5o3 

i4 

9,517 

i5 

9,532 

14 

9,546 

i5 

9,56i 

i4 

o,o324 

0,19 

10,016 

i5 

io,o3i 

i5 

10,046 

i5 

10,061 

i5 

10,076 

16 

10,092 

i5 

o,o36i 

0,20 

10,543 

iC 

10,559 

16 

10,575 

16 

10,591 

16 

10,607 

16 

10,623 

i5 

o,o4oo 

0,21 

1 1 ,070 

16 

1 1 ,086 

17 

ii,io3 

17 

11,120 

17 

1 1,1 37 

16 

ii,i53 

17 

0,044 1 

0,22 

1 1,596 

lb 

1 1,614 

16 

1 1 ,632 

17 

1 1 ,649 

18 

1 1 ,667 

17 

11,684 

18 

0,0484 

0,23 

12,123 

'9 

12,142 

18 

13,160 

19 

12,179 

ifc 

12,197 

18 

12,21 5 

19 

o,o529 

0,24 

1 2 .65o 

2<i 

1 2 ,670 

19 

12,689 

19 

12,708 

19 

12,727 

19 

.2,746 

'9 

0,0576 

0,25 

1 3,177 

20 

13,197 

20 

i3,2i7 

20 

i3,237 

20 

i3,257 

20 

.3,277 

20 

0,0625 

0,26 

1 3,704 

2  I 

i3,7?5 

21 

1 3,746 

20 

13,766 

21 

13,787 

21 

1 3,808 

30 

0,0676 

0,27 

i4,23i 

21 

l4,252 

22 

14,274 

22 

14,296 

21 

i4,3i7 

22 

14,339 

21 

0,0729 

0,28 

1 4,758 

22 

14,780 

22 

14,802 

23 

14,825 

23 

14,847 

22 

14,869 

33 

0,0784 

0,29 

0,284 

23 

1 5,3o7 

24 

i5,33i 

23 

i5,354 

23 

.5,377 

23 

1 5,400 

33 

0,084 1 

o,3o 

1 5,81 1 

24 

1 5,835 

24 

1 5,859 

24 

1 5,883 

24 

.5,907 

24 

15.931 

24 

0,0900 

0,3 1 

1 6,338 

24 

16,362 

2  5 

16,387 

25 

i6,4i2 

25 

.6,437 

34 

16,461 

a5 

0,0961 

0,32 

16,864 

26 

16,890 

25 

16,915 

26 

i6,g4i 

26 

16,967 

35 

16,992 

25 

0,1024 

0,33 

17,391 

26 

17,417 

27 

17,444 

26 

17,470 

26 

.7,496 

37 

17,523 

26 

0,1089 

0,34 

17,9'7 

28 

17,945 

27 

17,97' 

37 

17,999 

37 

18,026 

27 

i8,o53 

27 

0,1 156 

0,35 

18,444 

28 

18,472 

28 

i8,5oo 

28 

18,528 

28 

i8,556 

28 

i8,584 

37 

0,1225 

o,36 

18,970 

'9 

18,999 

29 

19,028 

39 

19,057 

28 

19,085 

39 

19,114 

39 

0,1296 

0,37 

19.497 

'9 

19.526 

3o 

19,556 

'9 

19,585 

3o 

19,615 

29 

.9,644 

3o 

0,1 369 

o,38 

20,023 

3o 

20  o53 

3i 

20,084 

3o 

20,Il4 

3i 

20,145 

3o 

20,175 

3o 

0,1444 

0,39 

20,549 

32 

2o,58i 

3i 

20,612 

3i 

20,643 

3! 

20,674 

3i 

20,705 

3i 

0,l52I 

o,4o 

2 1 ,076 

32 

21,108 

32 

2I,l4o 

33 

21,172 

32 

2I,304 

3i 

21,235 

32 

0,1600 

0,4 1 

2 1 ,602 

33 

2  1,635 

32 

21,667 

33 

2  1 ,700 

33 

21,733 

33 

3 1 ,766 

32 

0,1681 

0,42 

22,128 

34 

22,162 

33 

21,195 

34 

22,229 

33 

23,262 

34 

22,296 

33 

0,1764 

0,43 

22,654 

34 

22,688 

35 

33,733 

34 

22,757 

35 

22,792 

34 

22,826 

34 

0,1849 

0,44 

23,180 

35 

23,2l5 

36 

23,25l 

35 

23,286 

35 

23,321 

35 

23,356 

35 

0,1936 

0,45 

23,706 

36 

23,742 

36 

33,778 

36 

23,8i4 

36 

33,85o 

36 

33,886 

36 

0,2025 

o,5o 

26.335 

40 

26,375 

4o 

26,41 5 

40 

26,455 

4o 

26,495 

40 

26,535 

4o 

o,25oo 

0,55 

28.963 

ii 

39,007 

AA 

29,05 1 

Ai 

29,095 

AA 

29,139 

AA 

29,183 

AA 

o,3o35 

0,60 

31,589 

48 

3 1,637 

48 

3i,685 

48 

31.733 

48 

31,781 

48 

31,829 

48 

o,36oo 

o,65 

34,21 3 

52 

34,265 

52 

34,3i7 

53 

34,369 

52 

34,421 

52 

34,473 

52 

o,42a5 

o,7t< 

36,835 

56 

36,891 

56 

36,947 

57 

37,004 

56 

37,060 

56 

37,116 

56 

0,4900 

0,75 

39,455 

60 

39,51 5 

60 

39,575 

61 

39,636 

60 

39,696 

60 

39,756 

60 

o,56a5 

0,80 

42,072 

64 

42,i36 

65 

42,201 

64 

42,265 

64 

42,329 

65 

4?, 394 

64 

o,64oo 

o,85 

44,687 

68 

44,755 

69 

44,834 

68 

44,893 

69 

44,961 

68 

45,029 

68 

o,7aa5 

0,90 

47,399 

73 

47,373 

73 

47,445 

73 

47,517 

73 

47,589 

73 

47,662 

73 

0,8100 

0,95 

49.908 

77 

49,985 

77 

50,062 

77 

5o,i39 

76 

5o,2i5 

77 

50,292 

76 

0,9035 

1,00 

52,5i5 

81 

52,596 

81 

52,677 

80 

53,757 

81 

53,838 

81 

52,919 

80 

1 ,0000 

5,4121 

5,4450 

5,4781 

5,5112 

5,5445 

5,5778  1  c^  1 

4  .  (  r  +  r  "  )  ^  I 

r  r'   +  r'-- 

nearly.                      | 

l'ri>|>.  purts  liir  tli(>  sum  uf  tlio  Itiiilii. 

1  I  2  I  3  I  4  I  5  I  6  I  7  I  8  I  9 


536 

537 

528 

539 

53o 

53i 

53 

53 

53 

53 

53 

53 

io5 

io5 

106 

106 

106 

106 

1 58 

1 58 

1 58 

1 59 

1 59 

1 59 

210 

211 

211 

312 

212 

212 

263 

264 

264 

365 

265 

266 

3.6 

3i6 

3<7 

3i7 

3i8 

3.9 

368 

369 

370 

370 

37. 

373 

421 

433 

422 

433 

434 

425 

473 

474 

475 

476 

477 

478 

532 

53 
106 
160 

2l3 

266 

3,9 

373 
426 

479 


45 
46 

47 

48 

49 

5o 
5i 

52 

53 

54 

55 
56 

57 
58 

59 

60 
61 
62 
63 
64 

65 
66 

67 
68 

69 

70 
80 

90 
100 


10 

16 

1  1 

16 

1 1 

16 

1 1 

17 

1  1 

17 

1 1 

.7 

12 

17 

12 

.8 

I  2 

18 

12 

.8 

12 

19 

l3 

.9 

i3 

19 

i3 

20 

i3 

20 

i3 

20 

i4 

20 

.4 

21 

.4 

2  I 

16 

24 

18 

37 

2< 

3.^ 

23 
23 

24 

25 

26 

27 
28 
29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 

4o 

4i 
4i 
42 
43 
AA 

45 
46 
47 
48 

49 

5o 
5o 
5i 

52 

53 

54 
55 
56 

57 
58 

59 
59 
60 
61 
62 

63 

73 
81 
90 


Al3 


TABLE 

II. 

—  To  find  the  time 

T 

the  sum  of  the  rad 

■>»•+/■", 

ind 

the  chord 

c  being  given. 

Sum  oflhe  lUtiii  T-}-r".                                                                                                                           | 

Chord 
C. 

0,00 

3,35 

3,36 

3,37 

3,38 

3,39 

Days  |dir. 

3,40 

3,41 

3,42 

3,43 

Days  |dir. 

3,44 

Day^  |(lir. 

Days  |dil. 

Days  |dil'. 

Days  \i\L 

Days  |d 

it'.       Days  lilif. 

Days|dil'. 

llaysldir. 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,532 

1 

0,533 

1 

0,534 

0 

0,534 

1 

0,535 

I 

o,536 

I      0,537 

1 

o,538 

0 

o,538 

I 

0,539 

I 

0,000 1 

0.02 

1,064 

2 

1,066 

1 

1,067 

2 

i,o6g 

I 

1,070 

3 

1,072 

I      1 ,073 

2 

1,075 

2 

1,077 

1 

1,078 

3 

o,ooo4 

0,n3 

1,596 

2 

1,598 

3 

1,601 

2 

i,6c;3 

3 

i,6o5 

3 

1,608 

3       1,610 

3 

i,6i3 

2 

1, 61 5 

2 

1,617 

3 

0,0009 

o,o4 

2,128 

3 

3,l3l 

3 

2,i34 

3 

3,1 37 

4 

3,l4l 

3 

2,144 

3     2,147 

3 

2,i5o 

3 

3,i53 

3 

3,1 56 

4 

0,001 6 

o,o5 

3,660 

4 

2,664 

4 

3,668 

4 

3,672 

4 

2,676 

4 

3,680 

4     3,684 

4 

2,688 

4 

2,692 

3 

3,6g5 

4 

0,0025 

0,06 

3,192 

5 

3,197 

4 

3,301 

5 

3.206 

5 

3,2  1  I 

5 

3,316 

4    3,220 

5 

3,325 

5 

3,23o 

5 

3,335 

4 

o,oo36 

0,07 

3,724 

5 

3,73g 

6 

3,735 

6 

3;74i 

5 

3,746 

e 

3,752 

5    3,757 

6 

3,763 

5 

3,768 

6 

3,774 

5 

0,0049 

0,08 

4,356 

6 

4,262 

7 

4,269 

6 

4,275 

6 

4,281 

7 

4,388 

6    4,294 

6 

4,3oo 

6 

4,3o6 

7 

4,3i3 

6 

0,0064 

0,09 

4,788 

7 

4,795 

7 

4,802 

7 

4,809 

7 

4,816 

7 

4,833 

8    4,83 1 

7 

4,838 

7 

4,845 

7 

4,853 

7 

0,008 1 

0,10 

5,320 

8 

5,328 

8 

5,336 

8 

5,344 

7 

5,35i 

8 

5,359 

8     5,367 

8 

5,375 

8 

5,383 

8 

5,391 

8 

0,0100 

0,11 

5,852 

8 

5,860 

9 

5,869 

9 

5,878 

9 

5,887 

8 

5,895 

9     5,go4 

9 

5,9 1 3 

8 

5,921 

9 

5,930 

8 

0,01 2 1 

0,12 

6,384 

9 

6,393 

10 

6,4o3 

9 

6,4 1 3 

10 

6,423 

g 

6,43 1 

10    6,44 1 

9 

6,45o 

9 

6,459 

10 

6,469 

9 

0,01 44 

0,1  3 

6,916 

10 

6,926 

10 

6,936 

10 

6,g46 

11 

6,957 

IC 

6,967 

10    6,977 

10 

6,987 

1 1 

6,998 

10 

7,008 

10 

0,0169 

o,i4 

7>447 

12 

7,459 

II 

7.470 

II 

7,481 

11 

7.493 

II 

7,5o3 

II     7,5i4 

II 

7,535 

II 

7,536 

1 1 

7.547 

1 1 

0,0196 

o,i5 

7.979 

12 

7-99' 

13 

8,oo3 

13 

8,oi5 

13 

8,027 

12 

8,039 

II     8,o5o 

12 

8,063 

13 

8,074 

12 

8,086 

12 

0,0335 

0,16 

8,5ii 

i3 

8,524 

i3 

8,537 

12 

8,54g 

i3 

8,562 

13 

8,574 

1 3     8,587 

i3 

8,600 

13 

8,612 

i3 

8,625 

12 

o,0256 

0,17 

9,043 

i3 

9,o56 

i4 

9,070 

i3 

g,o83 

IÂ 

9,097 

i3 

g,i  10 

i4    9,124 

i3 

9. '37 

l3 

9,i5o 

i4 

9.164 

i3 

0,0389 

0,18 

9,575 

i4 

9,58g 

i4 

9,6o3 

i5 

g,6i8 

i4 

9,632 

i4 

9,646 

i4    9,660 

i4 

9. M 

i5 

9,689 

i4 

9.703 

i4 

o,o324 

0,19 

10,107 

i5 

10,122 

i5 

io,i37 

i5 

10,l53 

i5 

10,167 

i5 

10,183 

i5  10,197 

i5 

10,212 

i5 

10,227 

i5 

10,242 

i4 

o,o36i 

0,20 

1 0,6  38 

16 

10,654 

16 

1 0,670 

16 

10,686 

16 

10,703 

16 

10,718 

i5  10,733 

16 

10,749 

.6 

10,765 

i5 

10,780 

16 

o,o4oo 

0,21 

1 1 , 1 70 

17 

11,187 

16 

Il,203 

17 

I  1,330 

17 

1 1,337 

16 

11,253 

17  11.370 

16 

11,286 

17 

ii,3o3 

16 

11,3,9 

17 

0,044 1 

0,22 

1 1 ,703 

17 

11.719 

18 

11,737 

■7 

11,754 

18 

■1,772 

17 

11,78g 

17  11 ,806 

18 

11,824 

17 

ii,84i 

17 

1 1 ,858 

17 

0,0484 

0,23 

12,234 

18 

12,352 

18 

12,270 

18 

12,288 

18 

i2,3o6 

■9 

12,325 

18  13,343 

18 

I2,36i 

18 

13,379 

19 

13,397 

18 

0,0529 

0,24 

12,765 

19 

12,784 

19 

i2,8o3 

19 

12,822 

19 

I2,84l 

■9 

13,860 

19  13,879 

19 

12,898 

'9 

12,917 

■9 

13,936 

19 

0,0576 

0,25 

13,397 

20 

1 3,3 1 7 

30 

i3,337 

19 

1 3,356 

30 

13,376 

20 

i3,3g6 

30  i3,4i6 

19 

1 3,435 

30 

1 3,455 

'9 

1 3,474 

20 

0,0625 

0,26 

13,828 

21 

1 3,849 

21 

13,870 

20 

1 3,890 

31 

13,911 

30 

1 3,931 

31  13,953 

30 

i3,g73 

31 

■3,993 

30 

i4.oi3 

21 

0,0676 

0,27 

i4,36o 

21 

i4,38i 

33 

i4,4o3 

21 

14,424 

33 

i4,446 

31 

14,467 

21   14,488 

21 

i4,5o9 

3  2 

i4,53i 

31 

i4,553 

31 

0,0729 

0,28 

14,892 

22 

14,914 

22 

14.936 

23 

14.958 

22 

i4,g8o 

32 

1 5,002 

33  i5  025 

22 

i5,o47 

33 

15,069 

22 

15,091 

31 

0,0784 

0,2g 

1 5,433 

33 

1 5,446 

33 

15,469 

33 

15,492 

33 

i5,5i5 

33 

1 5,538 

23  i5,56i 

33 

1 5,584 

33 

1 5,606 

23 

1 5,63g 

23 

0,0841 

o,3o 

15,955 

33 

15,978 

34 

16,002 

34 

16,026 

24 

i6,o5o 

23 

16,073 

24  16,097 

24 

16,121 

23 

i6,i44 

24 

16,168 

23 

0,0900 

0,3 1 

16,486 

25 

i6,5ii 

34 

16,535 

25 

i6,56u 

24 

1 6,584 

25 

16,609 

34  i6,633 

35 

i6,658 

24 

16,683 

24 

16,706 

25 

0,096 1 

0,32 

17,017 

36 

17,043 

25 

17,068 

36 

17,094 

35 

17,119 

25 

17,144 

35  17,169 

26 

17,195 

25 

17,330 

25 

17,345 

25 

0,1034 

0,33 

17,549 

26 

17,575 

26 

17,601 

26 

17,627 

36 

17,653 

27 

17,680 

26  17,706 

36 

17,733 

25 

17.757 

36 

17,783 

26 

0,1089 

0,34 

18,080 

27 

18,107 

37 

i8,i34 

27 

18,161 

27 

18,188 

27 

i8,2i5 

27  18,242 

26 

18,268 

27 

18,395 

37 

18,333 

26 

0,1 1 56 

0,35 

18,611 

38 

18,639 

28 

18,667 

38 

18,695 

27 

18,733 

28 

18,750 

28  18,778 

27 

i8,8o5 

28 

i8,833 

27 

18,860 

28 

0,1  325 

o,36 

19,143 

38 

19,171 

29 

ig.200 

28 

19,338 

29 

19,257 

38 

19,285 

29  i9,3i4 

28 

19,342 

28 

19,370 

29 

19.399 

38 

0,1396 

0,37 

19,674 

59 

19,703 

3o 

19,733 

29 

19,762 

29 

•9.79' 

39 

19,830 

3o  19,850 

29 

19,87g 

29 

19,908 

o9 

19.937 

29 

0,1 36g 

0,38 

2O,305 

3o 

30,235 

3o 

20,265 

3i 

20,296 

3o 

20,326 

3o 

20,356 

3o  2o,386 

3o 

20,416 

29 

20,445 

3o 

30,475 

3o 

0,1 444 

0,39 

30,736 

3i 

30,767 

3i 

20,798 

3i 

20,82g 

3i 

30,860 

3i 

3o,8gi 

3i  30,922 

3o 

2o,g52 

3i 

20,983 

3i 

31,Ol4 

3o 

0,1 52  I 

o,4o 

21,267 

32 

21,299 

32 

2i,33i 

32 

21.363 

3i 

21,394 

32 

31,436 

3i  31,457 

32 

2i,48g 

3i 

21,520 

33 

31,552 

3i 

0,1600 

0,4 1 

21,798 

33 

2  1,83. 

32 

3  1,863 

33 

21,896 

33 

21,928 

33 

2i,g6i 

32  21,993 

32 

22,025 

33 

33,058 

33 

33,090 

33 

0,1681 

0,42 

22,329 

34 

23,363 

33 

33,396 

33 

22,42g 

34 

22,463 

33 

23,496 

33  33,539 

33 

32,503 

33 

22,5g5 

33 

33,638 

33 

0,1764 

0,43 

33,860 

34 

22,894 

35 

32,939 

34 

22,963 

34 

22,997 

34 

23,o3i 

34  23,o65 

33 

33,og8 

34 

23,l32 

34 

23,166 

34 

0,1849 

0,44 

23,391 

35 

33,426 

35 

33,461 

35 

23,496 

35 

33,53i 

34 

23,565 

35  23,600 

35 

33,635 

34 

23,669 

35 

33,704 

35 

0,1936 

0,45 

23,g32 

36 

23,958 

35 

23,993 

36 

34,039 

36 

34,o65 

35 

24,100 

36  24, I 36 

35 

34,171 

36 

24,207 

35 

34,342 

35 

0,2025 

o,5o 

26,575 

40 

26,615 

40 

36,655 

39 

36,694 

40 

26,734 

39 

26,773 

4o  26,81 3 

39 

26,852 

40 

26,893 

39 

26,g3i 

39 

o,25oo 

0,55 

39,337 

•iA 

29,371 

43 

29.3i4 

Aà 

2g,358 

44 

29,402 

43 

39,445 

44  29,48g 

43 

39,533 

43 

29,575 

44 

39,619 

43 

o,3o25 

0,60 

31,877 

48 

31,935 

48 

3'i,973 

47 

33,030 

48 

33,068 

47 

33,ii5 

48  33,i63 

47 

33,210 

47 

33.357 

48 

32,3o5 

47 

o,36oo 

0,65 

34,525 

53 

34,577 

52 

34,62g 

5i 

34,680 

52 

34,732 

52 

34,784 

5i  34.835 

5i 

34,886 

53 

34,938 

5i 

34.989 

5i 

0,4225 

0,70 

37,173 

55 

37,327 

56 

37,283 

56 

37,339 

55 

37,394 

56 

37,450 

55  37.5o5 

56 

37,56i 

55 

37,616 

55 

37,671 

55 

0,4900 

0,75 

39,816 

60 

39,876 

59 

39.935 

60 

39.995 

60 

4o,o55 

59 

4o,ii4 

60  40,174 

59 

4o,233 

59 

40,393 

59 

40,35 1 

60 

o,5635 

0,80 

43,458 

64 

42,522 

63 

42,585 

64 

42,649 

64 

43,713 

63 

42,776 

54  43,840 

63 

42,C)o3 

63 

43.966 

64 

43,o3o 

63 

o,64oo 

0,85 

45,097 

68 

45,i65 

68 

45,333 

68 

45,3oi 

67 

45,368 

68 

45,436 

67  45.5o3 

68 

45,571 

67 

45,638 

67 

45,7o5 

67 

0,7235 

o,go 

47.734 

73 

47,806 

72 

47.878 

72 

47.950 

72 

48,022 

71 

48,093 

72  48,i65 

71 

48,236 

71 

48,3o7 

72 

48,379 

71 

0,8100 

0,95 

5o,368 

76 

5o,444 

76 

5o,53o 

76 

50,596 

76 

50,672 

76 

5o,748 

75  50,823 

76 

50,89g 

75 

50,974 

75 

5i,o4g 

75 

0,9035 

1  ,(  )i  ) 

52.999 

80 

53,07g 

80 

53,i5g 

80 

53,239 

80 

53,319 

80 

53,399 
5,780 

80  53,479 

79 

53,558 

80 

53,638 

79 

53,717 

79 

1 ,0000 

5,6113 

5,6448 

5,6785 

5,7122 

5,7461 

0    5,8141  1 

5,8482 1 

5,8825 1  5,91681 

c" 

^  .  (r  -j-  r")'*     or    r^  -y  r'"^    nearly.                                                                                                      | 

53i 

533 

533 

534 

535 

536 

537 

538 

539 

540 

I 

53 

53 

53 

53 

54 

54 

54 

54 

54 

54 

I 

2 

106 

106 

107 

107 

107 

107 

107 

108 

108 

108 

2 

3 

1 59 

160 

160 

160 

161 

161 

161 

161 

163 

162 

3 

4  ■ 

212 

2l3 

3l3 

214 

214 

3l4 

2l5 

2l5 

316 

216 

4 

5 

266 

266 

267 

367 

368 

268 

269 

269 

370 

270 

5 

6 

3i9 

319 

320 

320 

331 

333 

32? 

323 

333 

334 

6 

7 

373 

37? 

373 

374 

375 

375 

376 

377 

377 

378 

7 

8 

435 

436 

4a6 

427 

428 

439 

43o 

43o 

43 1 

432 

8 

9 

478 

A 

i79 

4 

80 

48 

I    1 

48 

2  1 

482 

483 

484 

485 

486 

9 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-j-r",  and  the  chord  c  being  given. 


tfuni  v)t'  the  Kudil    r -^  r  ' 


CJlurd 
C 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,01) 

0,10 
0,11 
0,12 
0,1 3 
o,i4 

0,1 5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 
0,24 

0,25 
0,26 
0,27 
0,28 
0,39 

o,3o 
o,3i 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

0,40 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
o,85 
0,90 
0,95 


3,45 


Duys  |ilil 


0,796 
1,336 

1,875 

3,4i5 

2,955 

3,4q4 
4,0.34 
4,573 
5,1 12 
5,652 

6,191 
6,-3 1 
7,370 
7,809 
8,348 

8,888 

9,427 

9,966 

2o,5o5 

21,044 

21,583 
22.122 
22,661 
23,200 
23,739 

24,377 
26,970 
29,663 
33,353 
35,040 
37,726 

4o,4t  I 
43,093 
45,773 
48,45o 
5 1, 1 24 
53,796 


0,000 
o,54o 
1,080 
1,620 
2,160 

2,699 
3,239 

3,779 
4,319 
4,859 

5,3qQ 
5,()38 
6,478 
7,018 
-.558 


8, 098 
8,637 
9,1-- 

9r'"i  '4 
10,2  56 


i3 


5,9513 


0,000 
0,541 
1,081 
1,622 
2,i63 

2,703 
3,244 
3,785 
4,325 
4,866 

5,4o6 

5,947 
6,488 
-,028 
-,56(i 

8.iotj 
8,650 

9- '9" 
9,-3. 
10,271 

10,812 
11,352 

1 1 ,893 
12,433 
12,973 

i3,5i4 
i4,o54 
14,594 
i5,i34 
15,675 

i6,2i5 
16,755 
17,295 
17,835 
18,375 

18,915 
19.455 
'9,995 
30,535 
21,075 

2 1, 61 4 

22,l54 

32,694 
23,333 
23,773 

24,3 1 3 
27,010 
29,705 
32,3g9 
35,ogi 
37,781 

40,470 
43,i56 
45,839 
48,531 

51,199 
53,875 


3,47 


Udys  |dir. 


0,000 
0,54 1 
1 ,08  3 
1 ,634 

2,l6t) 

2,707 
3,249 
3,790 
4,332 
4,873 

5,4i4 
5,956 
6,497 
7,0  38 
7,58o 


8,662 
9,204 
9,745 
10,286 

10,827 
1 1 ,369 
11,910 
i2,45i 
12,993 

i3,533 
14,074 
i4,6i5 
i5,i56 
15,697 

i6,238 

16,779 
17,320 
17,861 
18,402 

i8,g42 
19,483 
20,024 
20,565 
2 1 , 1  o5 

2 1 ,646 
22,186 
23.737 
33,267 
23,807 

24,348 
27,049 
29,748 
32,446 
35,i43 
37,836 

40,528 
43,219 
45.906 
48,592 
5 1, 274 
53,954 


3,48 


Days  Idii; 


5,9858 1  6,0205 


0,000 
0,543 
1,084 
1,627 
2,169 

2,711 
3,253 

3,796 
4,338 
4,880 

5,422 
5,964 
6,5o6 
7,048 
7,5yl 

8,i33 
8,675 
9,217 
9,759 
io,3oi 

10,843 
11,38 
11,927 
1 2 ,469 
i3,oi  1 

1 3,553 
14,095 
i4,636 
15,178 
15,720 

16,262 
i6,8o3 
17,345 
17,887 
18,428 

18,970 
i9,5ii 
2o,o53 
30,594 
3i,i36 

21,6- 

23,318 

22,759 

23,3oi 

23,842 

24,383 
27,088 
29,791 
32.493 
35,193 
37,891 

40,587 
43,281 
45,973 
48,662 
5 1, 349 
54,o33i 


3,49 


Dnys  jdif. 


0,000 
0,543 
1,086 
1,629 
2,172 

2,7l5 

3,258 
3,801 
4,344 
4,887 

5,43o 
5,973 
6,5 1 6 
-,o5y 
7,601 

8,144 
8,687 
9,23' 
9,^7 
io,3i6 

10,859 
1 1 ,40 1 
1 1 ,944 
12,487 
'  3,039 

13,572 
i4,i  i5 
i4,657 
1 5,200 
1 5,742 

i6,385 
16,838 
17,370 
17,912 
18,455 

18,997 
19,539 
20,082 
20,624 
21,166 

21,708 

23,35o 
22,792 

23,334 

23,876 

24:4>8 

27,127 

39,834 
32,540 
35,244 
37,946 

40,646 
43,344 

46,o4o 
48,733 
5r,424 
54,11! 


i3 


6,0552 


6,0901 


3,50 


I)ay4  |dir. 


o,coo 

0,544 

1 

1 ,088 

I 

i,63i 

: 

2,175 

3 

2,719 

4 

3,363 

4 

3,8c6 

6 

4,35o 

6 

4,894 

7 

5,438 

7 

5,981 

9 

6,53  5 

9 

7.C  69 

10 

7,6 1 3 

11 

8,1 56 

12 

8,700 

12 

9.243 

i4 

9,787 

i4 

1 0,33 1 

14 

10,874 

16 

ii,4i8 

16 

ii,g6i 

17 

i3,5o5 

18 

1 3,048 

'9 

13,593 

19 

i4,i35 

20 

14.678 

21 

l5,333 

31 

1 5,765 

23 

i6,3o8 

24 

16,85? 

34 

17,395 

35 

17.938 

26 

18,481 

27 

19,024 

27 

ig,567 

38 

30,110 

3Q 

30,653 

3o 

2i,ig6 

3i 

21,739 

3t 

22,383 

33 

22,825 

33 

23,368 

33 

23,910 

35 

24,453 

35 

27,166 

3q 

39,877 

43 

32,587 

46 

35,394 

5i 

38 ,001 

54 

4o,7o5 

58 

43,407 

62 

46, r  06 

67 

48,804 

70 

51,498 

75 

54,190 

78 

6,1250 


0,001  >o 
0,0001 
0,0004 

0,0(Ki9 

0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,0081 

0,0I  00 
0,01  3  1 

o,oi44 
0,0169 
0,01  g6 

*,0225 

0,02 56 
0,0289 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
0,0484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,0841 

0,0900 
0,0961 
0,1024 
o,io8g 
0,1 1 56 

0,1225 
0,1396 
o,  1 369 
0,1 444 

0,1  521 

0,1600 
0,1681 
0,1764 
0,1 84g 
0,1936 

0,3035 
0,2  5oo 
o,3o25 
0.3600 
0,4225 
0,4900 


(r  -t-  r'  )^  or  r'^  4"  '' "  ^   nearly. 


538 

539 

54 

54 

108 

108 

161 

162 

2l5 

216 

269 

270 

323 

323 

377 

377 

43o 

43 1 

484 

485 

540 

541 

542 

543 

54 

54 

54 

54 

108 

108 

108 

log 

162 

162 

i63 

i63 

216 

216 

217 

217 

270 

371 

271 

272 

324 

325 

335 

326 

378 

379 

379 

38o 

432 

433 

434 

434 

486 

487 

488 

48q 

544 

54 
log 
1 63 
218 
272 
336 
38 1 
435 
490 


Prni>.  imrts  (i>r  tlie  Kuiii  of  (lie  Uudii. 
,  I  2   I  3  I  4  I    5  I   6  I  7  1  8  I  9 


25 

3 

26 

3 

27 

3 

28 

3 

29 

3 

3o 

3 

3i 

3 

32 

3 

33 

3 

34 

3 

35 

4 

36 

4 

37 

4 

38 

4 

39 

4 

4o 

4 

4i 

4 

42 

4 

43 

4 

44 

4 

45 

5 

46 

5 

47 

5 

48 

b 

49 

5 

5o 

5 

5f 

5 

52 

5 

53 

5 

54 

5 

55 

6 

56 

6 

57 

6 

58 

b 

59 

6 

60 

6 

61 

6 

63 

6 

63 

6 

64 

6 

65 

7 

66 

7 

67 

7 

68 

7 

69 

7 

70 

7 

80 

8 

90 

9 

00 

10 

28  35 
32  40 
36 1  45 
40 


I 

1 
2 

1 

2 

2 

2 

3 

3 

3 

4 

4 

4 

5 

4 

5 

5 

5 

6 

6 

6 

6 

7 

6 

7 

8 

7 

8 

9 

8 

9 

10 

8 

10 

1 1 

9 

10 

12 

10 

1  1 

i3 

1 1 

13 

i4 

II 

i3 

i4 

13 

i4 

i5 

i3 

14 

16 

i3 

i5 

17 

14 

16 

18 

i5 

17 

'9 

i5 

18 

20 

16 

18 

21 

17 

19 

22 

18 

20 

23 

18 

21 

23 

19 

22 

24 

30 

23 

25 

20 

23 

26 

21 

24 

27 

22 

2  5 

28 

23 

26 

29 

23 

26 

3o 

24 

27 

3i 

25 

28 

33 

25 

29 

32 

26 

3o 

33 

37 

3o 

34 

27 

3i 

35 

28 

32 

36 

29 

33 

37 

29 

34 

38 

3o 

34 

3q 

3i 

35 

40 

32 

36 

4i 

32 

37 

4i 

33 

38 

42 

34 

38 

43 

34 

39 

44 

35 

4o 

45 

36 

4i 

46 

36 

43 

4" 

37 

43 

48 

38 

43 

49 

3q 

44 

5o 

3q 

45 

5o 

4o 

46 

5i 

4i 

46 

52 

4i 

47 

53 

42 

48 

54 

43 

49 

55 

43 

5o 

56 

44 

5o 

57 

45 

5i 

58 

46 

52 

59 

46 

53 

59 

47 

54 

60 

48 

54 

61 

48 

55 

62 

49 

56 

63 

5f) 

64 

72 

63 

72 

81 

70 

80 

90 

TABLE  II. 

—  To  find  the  time  T 

the  sum  0 

f  the  ra 

(lii 

'  +  r". 

am!  (he  chord  c  being  given. 

t^uin  .il'  the  Kiiclii  r  -|-  r".                                                                                                           1 

Chord 
C. 

3,51 

3,52 

3,53 

3,54  1 

3,55 

3,56 

3,57 

3,58 

3,59 

Days  l.lil'. 

3,60 

Day»  |(iil'. 

I)ilj3  IcIlT. 

Days  |ilil'. 

Dny»  1 

III'. 

Days  |.lif. 

Day*  \m: 

Days  |clil'. 

Days  |.lir. 

Days  |ilif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0U0 

0,000 

0,0000 

0,01 

0,545 

0 

0,545 

I 

0,546 

1 

0,547 

I 

0,548 

0 

0,548 

I 

0,549 

I 

o,55o 

1 

o,55i 

I 

0,552 

0 

0,0001 

0,02 

1,089 

2 

1,091 

1 

1,092 

2 

1,094 

1 

1,095 

2 

1,097 

I 

1,098 

2 

1,100 

1 

1,101 

2 

i,io3 

2 

0,0004 

o,o3 

1,634 

2 

1.636 

2 

1,638 

3 

i,64i 

2 

1,643 

2 

1,645 

3 

1,648 

2 

i,65o 

2 

1,653 

2 

1,654 

3 

0,0009 

o,o4 

2,178 

3 

2,181 

3 

2,184 

3 

2,187 

4 

2,191 

3 

2,194 

3 

2,197 

3 

2,200 

3 

2,2o3 

3 

2,206 

3 

0,0016 

o,o5 

2,723 

4 

2,727 

3 

2,730 

4 

2,734 

4 

2,738 

4 

2,742 

4 

2,746 

4 

2,75o 

4 

2,754 

3 

2,757 

4 

0,0025 

0,06 

3,267 

<; 

3,272 

5 

3,277 

4 

3,281 

5 

3,286 

5 

3,291 

4 

3,295 

5 

3,3oo 

4 

3,3o4 

5 

3,309 

4 

o,oo36 

0,07 

3,812 

5 

3,817 

6 

3,823 

5 

3,828 

6 

3,834 

5 

3,839 

5 

3,844 

6 

3,85o 

5 

3,855 

5 

3,860 

6 

0,0049 

0,08 

4,356 

7 

4,363 

6 

4,36y 

6 

4.375 

6 

4,38i 

6 

4,387 

6 

4,393 

7 

4,400 

6 

4,406 

6 

4,4 1 2 

6 

0,0064 

o,og 

4,901 

7 

4,908 

7 

4,915 

7 

4,922 

7 

4,929 

7 

4,936 

7 

4,943 

6 

4,949 

7 

4,956 

7 

4,963 

7 

0,008 1 

0,10 

5,445 

8 

5,453 

8 

5,461 

8 

5,469 

7 

5,476 

8 

5,484 

8 

5,492 

7 

5,499 

8 

5,5o7 

8 

5,5i5 

7 

0,0100 

0,1 1 

5,990 

8 

5,908 

9 

6,007 

8 

6,01 5 

9 

6,024 

8 

6,o32 

9 

6,o4i 

8 

6,049 

9 

6,o58 

8 

6,066 

9 

0,0121 

0,12 

6,5'34 

10 

6,544 

9 

6,553 

9 

6,562 

9 

6,571 

10 

6,58 1 

9 

6,590 

9 

6,599 

9 

6,608 

10 

6,618 

9 

0,0 1 44 

0,1 3 

7,079 

10 

7,089 

10 

7,099 

10 

7,109 

10 

7,119 

10 

7,129 

10 

7,139 

10 

7,149 

10 

7,1 5g 

10 

7,169 

10 

0,0169 

o,i4 

7,623 

II 

7,634 

II 

7,645 

II 

7,656 

1 1 

7,667 

10 

ifin 

1 1 

7,688 

1 1 

7,69g 

11 

7,710 

10 

7,720 

II 

0,0196 

0,1 5 

8,168 

1, 

8,179 

12 

8,191 

12 

8,2o3 

1 1 

8,2i4 

12 

8,226 

1 1 

8,237 

12 

8,249 

1 1 

8,260 

12 

8,272 

II 

0,0225 

0,16 

8,712 

1 3 

8,725 

12 

8,737 

12 

8,749 

i3 

8,762 

12 

8,774 

12 

8,786 

i3 

8,799 

12 

8,811 

12 

8,823 

12 

0,0256 

0,17 

9,257 

i3 

9,270 

i3 

9,283 

i3 

9'296 

i3 

9,309 

i3 

9,3i2 

i3 

9,335 

i3 

9,348 

i3 

g,36i 

14 

9.375 

i3 

0,028g 

0,18 

9,801 

i4 

9,8 1 5 

i4 

9,829 

i4 

9,843 

14 

9,857 

14 

9,871 

i3 

9,884 

i4 

9,898 

i4 

9.912 

14 

9,926 

i4 

0,0324 

0,19 

10,345 

i5 

io,36o 

i5 

10,375 

i4 

10,389 

i5 

I  o,4o4 

i5 

10,419 

i4 

10,433 

i5 

10,448 

i5 

io,463 

14 

10,477 

i5 

o,o36i 

0,20 

10,890 

i5 

10,905 

16 

10,921 

i5 

1  o.g36 

16 

10,952 

i5 

10,967 

i5 

10,982 

16 

1 0,998 

.5 

1 1, 01 3 

1 5 

11,028 

16 

o,o4oo 

0,21 

11,434 

16 

ii,45o 

16 

11,466 

17 

11,483 

16 

1 1 ,499 

16 

ii,5i5 

16 

ii,53i 

16 

11,547 

'7 

11,564 

16 

1 1 ,58o 

16 

o,o44i 

0,22 

1 1 ,978 

17 

I  1 :995 

■7 

12,012 

17 

1 2 ,029 

17 

i2,o46 

17 

1 2, 06 3 

17 

1 2 ,080 

17 

i2,<->97 

17 

12,1 14 

17 

12,l3l 

17 

o,o484 

0,23 

12,52.3 

17 

12,540 

18 

12,558 

18 

13,576 

18 

12,594 

17 

12,61 1 

18 

12,62g 

18 

12,647 

18 

12,665 

17 

12,682 

18 

o,o52g 

0,24 

13,067 

18 

i3,o85 

19 

i3,io4 

19 

i3,i23 

18 

i3,i4i 

19 

i3,i6o 

18 

13,178 

19 

13,197 

18 

i3,2i5 

18 

i3,233 

19 

0,0576 

0,25 

1 3,61 1 

19 

i3,63o 

30 

i3,65o 

'9 

13,669 

19 

1 3,688 

20 

1 3,708 

■9 

13,727 

19 

1 3,746 

'9 

13,765 

20 

1 3,785 

19 

0,0625 

0,26 

i4,i55 

20 

14,175 

20 

14,195 

21 

14,216 

20 

i4,236 

20 

14,356 

20 

14,276 

20 

14,396 

20 

i4,3i6 

20 

i4,336 

20 

0,0676 

0,27 

14,699 

21 

14,720 

21 

1 4,74 1 

21 

14,762 

21 

14,783 

21 

1 4,804 

21 

14,825 

20 

14,845 

21 

14,866 

21 

14,887 

20 

0,0729 

0,28 

1 5,243 

22 

i5,265 

22 

15,287 

22 

1 5,309 

21 

i5,33o 

22 

i5,352 

21 

15,373 

22 

15,395 

21 

i5,4i6 

22 

1 5,438 

21 

0,0784 

o>29 

15,788 

22 

i5,8io 

23 

1 5,833 

22 

1 5,855 

22 

15,877 

23 

15,900 

22 

15,922 

22 

i5,g44 

23 

15,967 

22 

1 5,989 

22 

0,084 1 

o,3o 

16,332 

23 

16,355 

23 

16,378 

23 

16,401 

24 

16,425 

23 

16,448 

23 

16,471 

23 

i6,4g4 

23 

i6,5i7 

23 

16,540 

23 

o,ogoo 

0,3 1 

16,876 

24 

16,900 

24 

16,924 

24 

16,948 

24 

16,972 

24 

16,996 

24 

17,020 

23 

17,043 

H 

17,067 

24 

17,091 

24 

0,0961 

0,32 

17,420 

25 

17,445 

24 

1 7,469 

25 

17,494 

25 

17,519 

25 

17,544 

24 

17,568 

35 

i7,5g3 

24 

17,617 

25 

1 7,642 

24 

0,1024 

0,33 

I  ■',964 

25 

17.989 

26 

i8,oi5 

25 

i8,o4o 

26 

18,066 

25 

18,091 

26 

18,117 

25 

18,143 

26 

18,168 

25 

18,193 

25 

0,1089 

0,34 

i8,5o8 

26 

18,534 

26 

i8,56o 

27 

18,587 

26 

i8,6i3 

26 

18,639 

26 

1 8,665 

27 

i8,6g2 

26 

18,718 

26 

18,744 

26 

0,1 156 

0,35 

19,05 1 

28 

19,079 

27 

19,106 

27 

i9,i33 

27 

19,160 

27 

19,187 

27 

ig,2i4 

27 

ig,24i 

27 

19,268 

27 

19.295 

26 

0,1225 

o,36 

19,595 

28 

19,623 

28 

I9,65i 

28 

19,679 

28 

19-707 

28 

19.735 

27 

19,762 

28 

19,790 

28 

19,818 

27 

1 9,845 

28 

0,1296 

0,37 

20,139 

29 

20,168 

29 

20,197 

28 

20,225 

29 

20,254 

38 

20,282 

29 

30,3 1 1 

28 

30,339 

29 

20,368 

28 

20,396 

29 

0,1369 

o,38 

2o,683 

29 

20,712 

3û 

20,742 

59 

20,771 

3o 

20,801 

29 

2o,83o 

'9 

20,8  5g 

3o 

20,88g 

29 

20,918 

29 

20,947 

29 

0,1 444 

0,39 

21,227 

3o 

21,257 

3o 

21,287 

3o 

2 1,3 1 7 

3i 

2  1,348 

3o 

21,378 

3o 

2 1 ,4û8 

3o 

21,438 

3o 

21,468 

3o 

21,498 

3o 

0,l52I 

o,4o 

21,770 

3i 

21,801 

3i 

21,832 

3i 

21,863 

3i 

21,894 

3i 

21,925 

3i 

2 1 ,956 

3i 

3 1  ,g87 

3i 

22,Olfi 

3o 

2  3,048 

3i 

0,1600 

o,4i 

22,3l4 

32 

22,346 

32 

22,378 

3i 

22,409 

32 

22.441 

32 

22,473 

3i 

22,5o4 

33 

22,536 

3 1 

22,567 

32 

22,599 

3i 

0,1681 

0,42 

22,858 

32 

22,890 

33 

22,923 

32 

22,955 

33 

22,988 

32 

23,020 

33 

23,o53 

32 

23,o85 

32 

23,1 17 

33 

33.i5o 

32 

0, 1 764 

0,43 

23,4oi 

34 

23,435 

33 

23,468 

33 

23,5oi 

33 

23,534 

34 

23,568 

33 

23,601 

33 

23,634 

33 

23,667 

33 

23,700 

33 

0,1849 

0,44 

23,945 

34 

23,979 

34 

24,01 3 

34 

24,047 

34 

24,081 

34 

24,ii5 

34 

24,149 

34 

24,i83 

34 

24,217 

34 

24,25l 

33 

0,1936 

0,45 

24,488 

35 

24,523 

35 

24,558 

35 

24,593 

35 

24,628 

34 

24,662 

35 

24,697 

35 

24,732 

34 

24,766 

35 

24,801 

34 

0,2025 

o,5o 

27,2o5 

39 

27,244 

38 

27,282 

39 

27,321 

39 

27,36o 

38 

27,398 

39 

27,437 

38 

27,475 

39 

37,5i4 

38 

27,552 

39 

o,25oo 

0,55 

29,920 

42 

29,962 

43 

3o,oo5 

43 

3o,o48 

42 

30,090 

43 

3o,i33 

42 

30,175 

43 

3o,2i8 

42 

3o,2fio 

42 

3o,3o2 

43 

o,3o25 

0,60 

32,633 

47 

33,680 

47 

32,727 

46 

32,773 

47 

32,820 

46 

32,866 

46 

32,912 

47 

32,959 

46 

33,oo5 

46 

33,o5i 

46 

o,36oo 

o,65 

35,345 

5i 

35,396 

5o 

35,446 

5i 

35,497 

5o 

35,547 

5o 

35,597 

5i 

35,648 

5< 

35,6()8 

5o 

35,748 

5o 

35,798 

5o 

0,4225 

0,70 

38,o55 

55 

38, no 

54 

38, 164 

55 

38,219 

54 

38,273 

54 

38,327 

54 

38,38i 

54 

38,435 

54 

38,48y 

54 

38,543 

54 

o,4goo 

0,75 

40,763 

5g 

40,822 

58 

40,880 

58 

40,938 

59 

40,997 

58 

4i,o55 

58 

4i,ii3 

58 

41,171 

58 

41,229 

57 

41,286 

58 

o,5625 

0,80 

43,469 

63 

43,532 

62 

43,594 

62 

43,656 

62 

43,718 

62 

43,780 

62 

43,842 

63 

43,904 

62 

43,966 

62 

44,028 

61 

o,64oo 

o,85 

46,173 

66 

46,239 

66 

46,3o5 

67 

46,372 

66 

46,438 

66 

46,5o4 

66 

46,570 

65 

46,635 

66 

46,701 

66 

46,767 

65 

0,7225 

0,90 

48,874 

7C 

48,944 

71 

49,0 1 5 

70 

49,085 

70 

49,1 55 

70 

49,225 

70 

49,295 

69 

49,364 

70 

49,434 

69 

49,5o3 

70 

0,8100 

0,95 

51,573 

74  5;  647 

74 

51,721 

74 

51,795 

74 

5i.86g 

74 

51,943 

74 

52,017 

74 

52,ogi 

73 

52,164 

74 

52,238 

73 

o,go3  5 

1,00 

54,268 

79  54,347 

78 

54,425 

78 

54,5o3 

78 

58 

54,58 1 

78 

54,659 

78 

54,737 

1  ,, 

54,814 

78 

54.892I  77 

54,969 

78 

1 ,0000 

6,16 

01 

1  6,19 

52 

6,23 

05 

6,26 

6,30 

13 

6,33 

68 

6,37 

25 

6,4082 

6,44 

41 

6,48 

00 

C^ 

(r  -|-  r")^     or     T^  -\-  r"'     nearly. 


543 

54 

109 

1 63 
317 
272 
326 
38o 
434 
489 


54 

log 
i63 
218 
273 
326 
38 1 
435 
4go 


545 

55 

log 
164 
218 
273 
327 
382 
436 
4gi 


546 

547 

548 

54g 

55o 

55i 

552 

55 

55 

55 

55 

55 

55 

55 

109 

log 

no 

no 

no 

no 

no 

1 64 

164 

1 64 

i65 

i65 

i65 

166 

218 

219 

219 

230 

220 

220 

221 

273 

274 

374 

275 

275 

276 

276 

328 

328 

329 

339 

33o 

33 1 

33 1 

382 

383 

384 

384 

385 

386 

386 

437 

438 

438 

439 

440 

44 1 

442 

4gi 

492 

4g3 

494 

4g5 

496 

497 

TABLE   II. — To  fiiul  tlic  time  T;  the  sum  of  the  radii  r-fr',  and  the  chord  <■  beini;  given. 


Sum  of  tJio 

RQ.lii  r+r  ■ 

Choiil 

c. 

3,61 

3,62 

Days  Idif. 

3,63 

3,64 

3,65 

3,66 

Days  Idif. 

Days  |dir. 

Days  Idif 

Days  Idif. 

Days  |dif. 

0,00 

0,000 

0,000 

0.000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,552 

1 

0,553 

I 

0,554 

I 

0,555 

c 

0,555 

1 

o,556 

I 

O.OOOI 

0,03 

i,io5 

I 

1,106 

2 

I,IO& 

I 

1,109 

2 

I, III 

I 

1,1  12 

2 

0,0004 

o,o3 

1,657 

2 

1,659 

2 

1,661 

3 

1,664 

2 

1,666 

2 

1,668 

2 

0,0009 

o,o4 

2,209 

3 

2,212 

3 

2,2l5 

3 

2,21b 

3 

2,221 

3 

2,224 

3 

0,0016 

o,o5 

2,761 

4 

2,765 

4 

2,760 

4 

2,773 

4 

2,777 

3 

2,780 

4 

0,0025 

0,06 

3,3i3 

5 

3,3i8 

5 

3323 

4 

3,327 

5 

3,333 

4 

3,336 

5 

o,oo36 

0,07 

3,866 

5 

3,871 

5 

3,876 

6 

3,882 

5 

3,887 

5 

3,892 

6 

0,0049 

0,08 

4,4 1 S 

6 

4,424 

6 

4.430 

6 

4,436 

6 

4,442 

6 

4,448 

n 

0,0064 

0,09 

4,970 

7 

4,977 

" 

4,984 

7 

4,99' 

" 

4,998 

7 

5,oo5 

6 

0,0081 

0,10 

5.522 

8 

5,53o 

8 

5,538 

- 

5,545 

8 

5,553 

8 

5,56i 

7 

0,0100 

0,1 1 

6:075 

8 

6,o83 

8 

6,091 

9 

6,100 

8 

6,108 

9 

6,117 

s 

0,0121 

0,1  3 

6,627 

9 

6,636 

g 

6,645 

9 

6,654 

9 

6,663 

10 

6,673 

9 

0,01 44 

0,1 3 

7.i7q 

10 

7,189 

i^, 

7,199 

10 

7,209 

10 

7,219 

IC 

7,229 

9 

0,0169 

0,1 4 

7,73i 

II 

7,742 

II 

7,753 

10 

7,763 

11 

7,774 

II 

7,785 

10 

0,01 96 

0,1 5 

8.283 

12 

8,295 

11 

8.3o6 

12 

8,3i8 

II 

8,329 

11 

8,340 

12 

0,0225 

0,16 

8.835 

i3 

8,848 

12 

8;86o 

12 

8,872 

12 

8,884 

12 

8,896 

i3 

0,02  56 

0,17 

9,388 

i3 

9,401 

i3 

9,4i4 

12 

9,426 

i3 

9,439 

i3 

9,452 

i3 

0,0289 

0,1  S 

9,940 

i3 

9,953 

i4 

9,967 

14 

9,981 

i4 

9,995 

i3 

10,008 

i4 

o,o324 

0,19 

10,492 

i4 

io,5o6 

i5 

10,521 

i4 

10,535 

i5 

io,55o 

i4 

10,564 

i5 

o,o36i 

0,20 

1 1 ,044 

i5 

11,059 

i5 

11,074 

16 

1 1 ,090 

i5 

ii,io5 

i5 

11,120 

i5 

o,o4oo 

0,21 

11,596 

16 

1 1, 61 2 

16 

11,628 

16 

11,644 

16 

1 1 ,660 

16 

11,676 

16 

0,044 1 

0,22 

I2,i48 

17 

I2,i65 

16 

12,181 

17 

12,198 

17 

I2,2l5 

17 

12,232 

16 

o,o484 

0,23 

12,700 

17 

13,717 

18 

12,735 

17 

12,752 

18 

12,770 

17 

12,787 

18 

0,0529 

0,24 

13,252 

18 

13,270 

18 

13,288 

19 

i3,307 

18 

i3,325 

18 

1 3,343 

19 

0,0576 

0,25 

1 3,804 

'9 

i3,823 

'9 

1 3,842 

19 

i3,S6i 

19 

1 3,880 

19 

13,899 

19 

0,0625 

0,26 

i4,356 

19 

i4,*75 

2(j 

14,395 

20 

i4,4i5 

20 

14,435 

20 

14,455 

20 

0,0676 

0,27 

i4,qo7 

21 

14.928 

21 

14,949 

20 

14,969 

21 

14,990 

20 

i5,oio 

21 

0,0729 

0,28 

15,459 

22 

1 5,48] 

21 

i5,502 

22 

i5,524 

21 

i5,545 

21 

1 5,566 

21 

0,0784 

0,29 

16,011 

22 

i6,o33 

23 

i6,o56 

22 

16,078 

22 

16,100 

22 

16,122 

22 

0,084 1 

o,3o 

i6,563 

23 

i6,586 

23 

16,609 

23 

i6,632 

23 

1 6,655 

22 

16,677 

23 

0,0900 

0,3 1 

17.115 

23 

I7,i38 

24 

17,162 

24 

17,186 

23 

17,209 

24 

17,233 

24 

0,0961 

0,32 

17,666 

25 

17,691 

24 

I7,7i5 

25 

17,740 

24 

17,764 

25 

17,789 

24 

0,1024 

0,33 

18,218 

25 

18,243 

26 

18,269 

25 

18,294 

25 

18,319 

25 

18,344 

25 

o,io8g 

0,34 

18,770 

26 

18,796 

26 

18,822 

26 

18,848 

26 

18,874 

26 

18,900 

25 

o,ii56 

0,35 

19,321 

27 

19,348 

27 

19,375 

27 

19,402 

26 

19,428 

27 

19,455 

27 

0,1225 

o,36 

19,873 

28 

19,901 

27 

19.928 

28 

19,956 

27 

19,983 

27 

20,010 

28 

0, 1 296 

0,37 

20,425 

28 

20,453 

28 

20,481 

28 

20,509 

29 

20,538 

28 

20,566 

28 

0,1369 

o,38 

20,976 

29 

2I,oo5 

29 

2i,o34 

29 

2 1 ,063 

29 

21,092 

29 

21,121 

29 

0,1 444 

0,39 

21,528 

29 

21,^57 

3o 

21,587 

So 

21,617 

3o 

21,647 

29 

21,676 

3o 

0,1 52  I 

o,4o 

22,079 

3i 

32,110 

3o 

22,l4o 

3i 

22,171 

3o 

22,201 

3i 

22,232 

3o 

0,1600 

o,4i 

22,63o 

32 

22,662 

3i 

22,6g3 

3i 

22,724 

32 

22,756 

3i 

22,787 

3i 

0,1681 

0,42 

23,182 

32 

23,2l4 

32 

23,246 

32 

23,378 

32 

23,3io 

32 

33,342 

32 

0,1764 

0,43 

23,733 

33 

23,766 

33 

23,799 

33 

23,832 

32 

23,864 

33 

23,897 

33 

0,1849 

0,44 

24,284 

34 

24,3i8 

34 

24,352 

33 

24,385 

34 

24,419 

33 

24,452 

M 

0,1936 

0,45 

24,835 

35 

24,870 

34 

24,904 

35 

24,939 

34 

24,973 

34 

25,007 

35 

0,2025 

o,5o 

27.591 

38 

27,629 

38 

27,667 

38 

27,705 

39 

27,744 

38 

27,782 

38 

o,25oo 

0,55 

3o,345 

42 

3o,387 

42 

30,429 

42 

3o,47i 

42 

3o.5i3 

42 

3o,555 

42 

o,3o25 

0,60 

33,097 

46 

33,143 

46 

33,189 

46 

33,235 

46 

33:281 

46 

33,327 

45 

o,36oo 

0,65 

35.848 

5o 

35,898 

5o 

35,948 

49 

35,997 

5o 

36,o47 

5o 

36,097 

^9 

0,4225 

0,70 

38,597 

54 

38,65 1 

53 

38,7o4 

54 

38,758 

54 

38,8i2 

53 

38,865 

53 

0,4900 

0,75 

41,344 

58 

4i,4o2 

57 

41,459 

58 

4i,5i7 

57 

41,574 

58 

4i,632 

57 

0,5625 

0,80 

44,089 

62 

44,i5i 

61 

44,212 

62 

44,274 

61 

44,335 

61 

44,3y6 

61 

o,64oo 

o,85 

46,832 

66 

46,898 

65 

46,963 

65 

47,028 

65 

47,093 

66 

47,159 

65 

0,7225 

0,90 

49,573 

69 

49,642 

70 

49,712 

6q 

49,781 

69 

49,8'5o 

69 

49,919 

68 

0,8100 

0,95 

52,3ii 

73 

52,384 

73 

52,457 

74 

52,53i 

7a 

52,6o3 

73 

52,676 

73 

0,9025 

1. 00 

55,047 

77 

55,124 

77 

55,201 

77 

55,278 

77 

55,355 

76 

55,43i 

77 

1 ,0000 

6,5161  1 

6,552-2  1 

6,5885  1 

6,6248 1 

6,66131 

6,6978  1 

Î  .  C  J-  +  r  "  )  =  or  r'  -f-  r  «  nearly.                     | 

55i 

552 

553 

55 

"55 

55 

no 

no 

III 

1 65 

166 

166 

220 

221 

221 

376 

276 

277 

33i 

33i 

332 

386 

386 

387 

44i 

442 

442 

4q6 

497 

498 

554 

55 
111 
166 
222 

277 
332 
388 
443 
499 


555 

56 
III 
167 
222 
278 
333 
389 

5oo 


556 

56 
III 
167 
222 
278 
334 
389 
445 


^■-■7 

56 
III 
167 

223 

279 
334 
390 

446 
5oi 


Trop,  purts  fur  tbo  sun)  uf  tlio  Radii. 

i|2|3|4|5|6|7|8|9 

I 
2 

3 


45 
46 

47 

48 

49 

5o 
5i 

52 

53 
54 

55 
56 

57 
58 

59 

60 
61 
62 
63 
64 

65 
66 
67 
68 

69 

70 
80 

90 


9|i4 
9 


i3 
i3 
i4 

i4 
i4 
i5 
i5 
16 

16 
16 

17 
17 
18 

18 
i4  18 
i4  19 
i4  19 
i5  20 


25  3o 


22 

23 

24 

25 

26 
26 

27 

25  28 


56 


56 

64 

63|72  81 

70I  80I00 


23 
23 

24 

25 

26 

27 
28 

29 

3û 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 

40 

4i 
4i 
43 
43 
A4 

45 
46 
47 
48 
49 

5o 
5o 
5i 

52 

53 

54 
55 
56 

57 
58 

59 
59 
60 
61 
62 

63 

72 


a14 


FABLE  II 

—  To  find  the  time  T 

,  the  sum  0 

f  the  radii 

r  +  ,-", 

and  the  chord  c 

being  give 

n. 

Sum  of  the  Radii  r  +  r  ".                                                                                                             1 

Chord 
C. 

3,67 

3,68 

3,69 

3,70 

3,71 

Days  |dif. 

3,72 

3,73 

3,74 

3,75 

3,76 

Days  \M: 

Days 

die. 

Days  |dif. 

Days 

dif. 

Days  |dif. 

Days  Idif. 

Days  |dir. 

Days  jdif. 

Days  |dif. 

0,00 
0,01 
0,02 

o,o3 
o,o4 

0,000 
0,557 

i,ii4 
1,670 
2,227 

I 
I 
3 
3 

0.000 

o;558 
i,n5 
1,673 

2,23o 

0 
2 
2 

3 

0.000 
o;558 
1,117 
1,675 

2,233 

I 
I 
2 
3 

0,000 
0,559 
1,118 

1,677 

2,236 

I 

2 

3 
3 

0,000 
o,56o 
1.120 
1,680 
2,239 

I 

I 

2 

3 

0,000 

o,56i 
1.121 

i;682 

3,242 

0 
2 

2 

3 

0,000 
0,56 1 

1,123 

1,684 
2,245 

1 

I 
3 
3 

0,000 
0,562 
1,124 
1,686 

2,248 

1 
2 

3 
3 

0,000 
o,563 
1,136 
1,689 
2,25l 

I 
I 
3 
3 

0,000 

o,564 
1,127 
1,691 

2,254 

0 

2 
2 

3 

0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

o,o5 
0,06 
0,07 
0,08 
0,09 

2,784 
3,341 
3,898 
4,455 
5,011 

4 
4 
5 
6 

3,788 
3,345 
3,903 

4,46i 
5,018 

4 
5 
5 
6 

7 

2,792 

3,35o 
3,908 
4,467 
5,035 

3 

5 
6 
6 

7 

2,795 

3,355 
3,914 
4,473 
5,o32 

4 
4 
5 
6 

2,799 
3,359 

3,919 

4,479 
5,039 

4 
5 
5 
6 
6 

2,8o3 
3,364 
3,934 
4,485 
5,045 

4 
4 
5 
6 

7 

2,807 
3,368 
3,929 
4,491 
5,o53 

4 
5 
6 
6 

2,811 
3,373 
3,935 
4,497 
5,059 

3 
4 
5 
6 

7 

2,8l4 
3,377 
3,940 

4,5o3 
5,066 

4 
5 
5 
6 
6 

2,818 
3,382 
3,945 
4,509 
5,072 

4 
4 
5 
6 

7 

0,0025 
o,oo36 
0,0049 
0,0064 
0,0081 

0,IO 

0,11 
0,12 
0,1 3 
o,i4 

5,568 
6,125 
6,682 
7,238 
7..795 

8 
8 

9 
10 
11 

5,576 
6,i33 
6,691 
7,248 
7,806 

7 
9 
9 
10 
10 

5,583 
6,143 
6,700 
7,358 
7,816 

8 
8 

9 
10 
II 

5,591 
6,i5o 
6,709 
7,268 
7,827 

7 

8 

9 
ro 
10 

5,598 
6, 1 58 
6,718 
7,278 
7,837 

8 
8 

9 
10 
11 

5,606 
6,166 
6,727 
7,288 
7,848 

7 
9 
9 
9 
II 

5,6i3 
6,175 
6,736 
7,297 
7,859 

8 
8 

i^ 
10 

5,621 
6,i83 
6,745 
7,3o7 
7,869 

7 
8 

9 
10 
u 

5,628 
6,191 
6,754 

7,3l7 
7,880 

8 

9 

9 

10 

10 

5,636 
6,200 
6,763 
7,337 
7,890 

8 

9 

9 

II 

0,0100 

0,013I 
0,0144 
0,0169 
0,0196 

0,1 5 
o,t6 
0,17 
0,18 
0,19 

8,352 

8,9"9 
9,465 
10,022 
10,579 

n 
12 
i3 
i4 
i4 

8,363 
8,921 
9.478 
io,o36 
10,593 

12 
12 

i3 
i3 
i4 

8,375 
8,933 

9,491 
10,049 
10,607 

II 
12 
i3 
i4 
i5 

8,386 
8,945 
9,5o4 
io,o63 
10,622 

II 
12 

i3 
i3 

1 4 

8:5? 

9,5i7 
10.076 
io,636 

12 
12 
i3 
i4 
i4 

8,409 

8,969 

g,53o 

10,090 

io,65o 

II 
12 
12 

i4 
i5 

8,420 
8,981 
9,542 
io,io4 
io,665 

11 

13 

i3 
i4 

8,43i 
8.993 
9,555 
10,117 
1 0,679 

II 
12 

i3 
i4 
i4 

8,442 

9,oo5 

9,568 

io,i3i 

10,693 

13 
13 
l3 

i3 
i5 

8,454 

9,017 

9,58i 

io,i44 

10,708 

II 

12 
12 

i4 
i4 

0,0225 

o,o256 
0,0289 
0,0824 
o,o36i 

0,20 
0,21 
0,22 

0,23 

0,24 

ii,i35 
1 1 ,693 
12,248 
t2,8o5 
i3,362 

i5 
16 

17 
17 
18 

ii.i5o 
ii;7o8 
12,265 
13,822 
i3,38o 

16 
16 

17 
18 
18 

11,166 
11,724 
12,282 
i3,84o 

13,398 

i5 
16 
16 

17 
18 

11,181 
1 1 ,74o 
12,298 
13,857 
i3,4i6 

i5 
i5 
17 
18 
18 

11,196 

11,755 
I2,3i5 
12,875 
1 3,434 

i5 
16 

i7 
17 
18 

11,211 

11,771 

12,332 

12,893 

1 3,453 

i5 
16 
16 

17 
18 

11.236 
11,787 
12,348 
1 2 ,909 
1 3,470 

i5 
16 

17 
18 
18 

11.241 
ii,8o3 
12,365 

12,027 

1 3,488 

i5 
16 
16 
17 
18 

1 1,256 
1 1 ,8 1 9 
I2,38i 
12,944 
i3,5o6 

1 5 
i5 
17 
17 
18 

11,271 
11.834 
i2,3q8 
12,961 
1 3,524 

i5 
16 
16 

17 
18 

o,o4oo 
0,044 1 
o,o484 
0,0529 
0,0576 

0,25 
0,26 
0,27 

0,28 
0,29 

13,918 
14,475 
i5,o3i 
1 5,587 
16,144 

19 
19 
30 
22 
22 

13,937 
14,494 
i5,o5i 
1 5,609 
16,166 

19 
20 
21 
21 

23 

i3,o56 
i4,5i4 
15,072 
i5,63o 
16,188 

19 
20 
20 
21 
22 

i3,975 
14,534 
15,092 
i5,6'5i 
16,210 

19 
19 
21 
21 
22 

1 3,994 
14,553 
i5,ii3 
15,672 
16,232 

19 
20 
20 
21 
22 

i4,oi3 
14,573 
i5,i33 
15.693 
16,254 

18 

19 
20 
21 
21 

i4,o3i 
14,593 
i5,i53 
i5,7i4 
16,275 

19 
20 

31 
22 
23 

i4,o5o 
i4,6i2 
i5,i74 
1 5,736 
16,297 

19 
30 
20 
21 
22 

14,069 
i4,632 
15,194 
15,757 
16,319 

19 
19 
20 
21 

23 

i4,o88 
1 4,65 1 
i5,2i4 
1 5,778 
i6,34i 

19 
20 
21 
21 
21 

0,0625 
0,0676 
0,0739 
0,0784 
0,084 I 

o,3o 
0,3 1 

0,32 

0,33 
0,34 

16,700 
17,257 
I7,8i3 
18,369 
18,925 

33 
23 

24 

25 

26 

16,723 
17,280 
17,837 
18,394 
18,951 

23 
24 
24 
25 
26 

16,746 
i7,3o4 
17,861 
18,419 
18,977 

22 

23 
25 
25 

26 

16,768 
17,327 
17,886 
18,444 
19,003 

33 

33 

24 

25 
25 

16,791 
17,350 

17,910 
18,469 
19,028 

23 

24 
24 

25 

26 

i6,8i4 
17,374 
17,934 
18,494 
19,054 

23 

23 
34 
25 
26 

i6,836 

17,397 
17,958 
18,519 
19,080 

23 
24 
24 
35 
35 

16,859 
17,421 
17,982 
18,544 
ig,io5 

22 

23 

24 

35 

26 

16,881 
17,444 
18.006 
18,569 
ig,i3i 

33 
33 
24 
24 
35 

16,904 
17,467 
i8,o3o 
18,593 
I9,i56 

22 

23 

24 

25 

26 

o,ogoo 
0,0961 
0,1024 
0,1089 
o,ii56 

0,35 
0,36 
0,37 
0,38 
0,39 

19,482 
2o,o38 
20,594 
2i,i5o 
21,706 

26 

27 
28 

3o 

19,508 
20,065 
20,622 
31,179 
31,736 

27 
27 
28 

29 
29 

19,535 
20,092 
2o,65o 
21,208 
2 1 ,765 

26 
38 
28 
28 

3o 

19,561 
20,120 
20,678 

21,236 
2  1 ,795 

27 

27 

28 
29 

29 

19,588 

20,147 
20,706 

21,365 

21,824 

26 

27 
28 

=9 
3o 

19,614 
20,174 
20,734 
31,294 
21,854 

26 
27 
28 
28 
29 

19,640 
20,201 
30,762 

31,333 

21,883 

27 
27 
28 

29 
29 

19,667 
20,228 
20,790 
2i,35i 
21,912 

26 

27 
28 

^9 
3o 

19,693 
20.355 
20,818 
2i,38o 
21,942 

26 

27 
27 
28 

29 

19,719 
20,282 
20,845 
21,408 
21,971 

27 
27 
28 

29 
29 

0,1225 
0,1296 
o,i36g 
0,1444 

0,l52I 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

22,262 
22,818 
23,374 
23,930 
24,486 

3o 
3. 

32 

33 
33 

22,292 
33,849 
23,4o6 
23,963 
24,519 

3i 
3i 

32 
32 

34 

22,323 
23,88o 

23,438 
23,995 
24,553 

3o 
3i 

32 

33 
33 

33,353 
22,911 
23,470 
24,028 
24,586 

3o 
3. 
3i 

32 

33 

22,383 
22,942 
23,5oi 
24,060 
24,619 

3i 
3i 

32 

33 
33 

32,4l4 

23,973 
23,533 
24,093 
24,652 

3o 
3i 

32 

^4 

22,444 
23,004 
23,565 
24,125 
24,686 

3o 
3i 
3i 
33 
33 

22,474 
23,o35 
23,596 
24,i58 
24,719 

3o 
3i 

32 
32 

33 

33,5o4 

33.066 
23,628 

24,190 

24,752 

3o 
3i 
3i 

32 

33 

22,534 
23.097 
23,659 

24,232 
24,785 

30 
3o 

32 
32 

33 

0,1600 
0,1681 
0, 1 764 
0,1849 
0,1986 

0,45 
o,5o 
0,55 
0,60 
0,65 
0,70 

25,042 
37,820 
30,597 
33.372 
36, 1 46 
38,918 

34 
38 
43 
46 
5o 
54 

25,076 
27,858 
3o,63ci 
33,418 
36,196 
38,972 

34 
38 
4i 
45 

49 
53 

25,110 

27,896 

3o,68o 
33,463 
36,345 
39,025 

34 
38 
42 
46 

25,i44 
37,934 
3o,722 
33,5o9 
36,294 
39,078 

34 
37 
42 
45 
5o 
53 

25,178 
27,971 
30,764 
33,554 
36,344 
39,i3i 

34 
38 
4i 
46 

49 
53 

25,212 
28,009 

3o,8o5 
33,600 
36,393 
39,184 

34 
38 
42 
45 

49 
53 

25,246 
28,047 
3o,847 
33,645 
36,442 
39,237 

34 
38 
4i 
45 

49 
53 

25,280 
28,085 
3o,888 
33.690 
36,491 
39,290 

34 
37 
42 
46 

49 
53 

25,3i4 
28,122 
3o,93o 
33,736 
36,540 
39,343 

34 
38 
4i 
45 

È 

25,347 
28,160 

3o,97i 

33,781 

36,589 
39,396 

34 
37 
4i 
45 

52 

0,2025 
0,3  5oo 
o,3o35 
o,36oo 
0,4225 
0,4900 

0,75 
0,80 
0,85 
o,go 
0,95 
1  1,00 

41,689 
44,457 
47,334 
49,987 
53,749 
55,5o8 

57 
61 
64 
69 

73 

77 

4 1, 746 
44.5i8 
47,288 
5o.o56 

52,833 

55,585 

57 
61 
65 

69 

72 
76 

4i,8o3 

44,579 
47,353 
5o,i25 
52,894 
55,661 

57 
61 

65 
68 

73 
76 

4 1, 860 
44,64o 
47,418 
50,193 
52,967 
55,737 

57 
61 
64 
69 

73 

77 

41,917 
44,701 
47,482 
50,262 
53,039 
55,8x4 

57 
60 
65 
68 
72 
76 

41,974 
44,761 
47,547 
5o,33o 
53,111 
55,890 

57 
61 
64 
69 

72 
76 

42,o3i 
44,822 
47,611 
50,399 
53,i83 
55,966 

56 
61 
65 
68 

72 
76 

42,087 
44,883 
47,676 
50.467 
53;255 
56,o42 

57 
60 
64 
68 

72 
75 

42,144 
44,943 
47,740 
5o,535 
53,337 
56,117 

56 
60 
64 
68 

72 
76 

43,300 
45,oo3 
47,804 
5o,6o3 
53,399 
56,193 

57 
61 
64 
68 

72 
76 

0,5635 
o,64oo 
0,7225 
0.8100 
0,9025 
1 ,0000 

6,7345 

6,7712 

6,8081 

6,84 

50 

6,8821 

6,9192 

6,9565 

6,99 

38 

7,0313 

7,0688 

i 


(r  -\~   r")^  or   r"^  -\~  r"^     nearly. 


556 

56 
III 
167 
222 
278 
334 
389 
445 
5oo 


557 

56 
II I 

167 

233 
279 
334 
390 

446 
5oi 


558 

56 
112 

167 

223 

279 

335 
391 
446 

502 


559 

56 

112 
168 
224 
280 

335 
391 
447 
5o3 


56o 

56 
112 

168 
224 
280 
336 
392 
448 
5o4 


56i 

56 
112 
168 

324 
281 
337 
393 

449 
5o5 


562 

56 
112 
169 

225 
281 
337 
393 

45o 
5o6 


563 

56 
ii3 
169 

225 
282 

338 
3g4 
45o 
507 


564 

56 
ii3 
169 
226 
282 
338 
395 
45 1 
5o8 


TABLE  II.  =^  To  find  the  time  T;  the  sum  of  the  radii  r  -j-r  ",  and  the  chord  c  being  given. 


Sum  of  the  Rmlii  r-l-r".                         | 

Prop,  parts  for  the  sum  of  the  Radii.    1 

1       ITI    /ICI/'I—   1C>1„I 

Cliord 
C. 

3,77 

3,78 

3,79 

3,80 

3,81  ' 

3,82 

I  1  2  1  3  1  4  1  5  1  6  1 

7  1  0  1  9  1 

1 
2 
3 

0 
0 

0 

0 
0 

0 

I 
1 

0 

I 

1 
I 
2 

1 

I 
2 

I 
1 

2 

I 
2 
2 

I 
2 
3 

Days  |ilir. 

Days  |dif. 

Days  Idir. 

Days  |dir. 

Days  |dif. 

Days  |dil'. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,564 

1 

o,565 

I 

o,566 

1 

0,567 

0 

0,567 

I 

0,568 

I 

0,000 1 

4 

0 

I 

2 

2 

3 

3 

3 

4 

0,02 

1,129 

I 

i,i3o 

2 

l,l32 

1 

i,i33 

2 

I,l35 

I 

i,i36 

3 

0,0004 

o,o3 

1,693 

2 

1,695 

3 

1,698 

2 

1,700 

2 

1,702 

2 

1,704 

3 

0,0009 

5 

2 

2 

3 

3 

4 

4 

5 

o,o4 

3,257 

3 

2,260 

3 

2,263 

3 

2,266 

3 

2,369 

3 

2,272 

3 

0,0016 

6 

7 

2 

2 

2 
3 

3 
4 

4 
4 

4 
5 

5 
6 

5 
6 

o,o5 

2,823 

4 

2,826 

3 

2,829 

4 

2,833 

4 

2,837 

3 

2,84o 

4 

0,0025 

8 

2 

2 

3 

4 

5 

6 

6 

7 

0,06 

3,386 

5 

3.391 

4 

3.395 

5 

3,4oo 

4 

3,4o4 

5 

3,409 

4 

o,oo36 

9 

2 

3 

4 

5 

5 

6 

7 

8 

0,07 

3,950 

6 

3i956 

5 

3,961 

5 

3,966 
4,533 

5 

3,971 

6 

3.977 

5 

0,0049 

10 

2 

3 

4 

5 

G 

7 
8 

8 

9 
10 

0,08 

4,5 1 5 

6 

4,521 

6 

4,527 

6 

6 

4,539 

6 

4,545 

6 

0,0064 

1 1 

2 

3 

4 

6 

7 
7 

9 

10 

0,09 

5,079 

7 

5,086 

5,093 

6 

5,099 

7 

5,106 

7 

5,u3 

6 

0,008 1 

12 

2 

4 

5 

6 

8 

11 

0,10 

5.643 

8 

5,65 1 

~ 

5,658 

8 

5,666 

7 

5,673 

8 

5,681 

7 

0,0100 

i3 

i4 

3 

3 

4 
4 

5 
6 

7 
7 

8 
8 

9 

10 

10 
1 1 

12 
i3 

o,u 

6,208 

S 

6,216 

8 

6,224 

8 

6,232 

9 

6,241 

8 

6,249 

8 

0,01 2 1 

0,12 

6,772 

9 

6,781 

9 

6,790 

9 

C,799 

9 

6,808 

9 

6,817 

9 

0,01 44 

i5 

2 

3 

5 

6 

8 

9 

II 

12 

i4 

o,i3 

-,336 

10 

7,346 

10 

7.356 

10 

7,366 

9 

7,375 

10 

7,385 

10 

0,01 6g 

16 

2 

3 

5 

6 

8 

10 

II 

i3 

i4 

o,i4 

7, go  I 

10 

7.9" 

11 

7,922 

10 

7,935 

10 

7.942 

11 

7,953 

10 

0,01 96 

17 
18 

3 
2 

3 
4 

5 
5 

7 

7 

9 
9 

10 
u 

12 
i3 

i4 
i4 

i5 
16 

0,1 5 

8,465 

1 1 

8,476 

11 

8,487 

12 

8,499 

11 

8,5io 

11 

8,521 

II 

0,0225 

■9 

2 

4 

6 

8 

10 

1 1 

i3 

i5 

17 

0,16 

9>"20 

12 

9.041 

12 

9,o53 

12 

9,065 

12 

9.077 

12 

9.089 

13 

o,o256 

16 

18 

0,17 

9.593 

i3 

9,606 

i3 

9.619 

12 

9,63 1 

i3 

9.644 

i3 

9,657 

12 

0,028g 

20 

2 

4 

6 

8 

10 

13 

i3 

i4 

0,18 

io,i58 

i3 

10,171 

i3 

10,184 

i4 

10,198 

i3 

10,211 

i4 

10,225 

l3 

o,o324 

21 

2 

4 

6 

8 

II 

i5 

17 

19 

0,19 

10,722 

i4 

10,736 

i4 

io,75o 

i4 

10,764 

i5 

10,779 

i4 

10,793 

i4 

o,o36i 

22 

23 

2 

2 

4 
5 

7 

n 

9 
9 

II 
12 

i3 
i4 

i5 
16 

18 
18 

20 
21 

0,20 

11,286 

i5 

ii,3oi 

i5 

ii,3i6 

i5 

II, 33 1 

i5 

11,346 

i5 

ii,36i 

i4 

o,o4oo 

24 

2 

5 

7 

10 

12 

i4 

17 

19 

22 

0,21 

ii,85o 

16 

11,866 

16 

11,882 

i5 

11,897 

16 

11,913 

i5 

11,928 

16 

o,o44 1 

35 

3 

5 
5 
5 
6 

8 
8 
8 
8 

10 

i3 

i5 

18 

20 

23 

0,22 

12,414 

17 

i2,43i 

16 

12,447 

17 

12,464 

16 

1 3,480 

16 

12,496 

17 

o,o484 

26 

3 
3 
3 

10 

i3 

16 

18 

2 1 

23 

0,23 

".978 

18 

12,996 

17 

i3,oi3 

17 

i3,o3o 

17 

1 3,047 

17 

1 3,064 

17 

0,0529 

i4 
i4 

16 

19 

30 

22 

24 

25 

0,24 

i3,542 

18 

i3,56o 

18 

13,578 

18 

13,596 

18 

i3,6i4 

18 

1 3,632 

i8 

0,0576 

27 

28 

1 1 
II 

17 

22 

0,25 

14,107 

18 

i4,i25 

19 

i4,i44 

'9 

i4,i63 

18 

i4,i8i 

19 

l4>200 

18 

0,0635 

29 

3 

6 

9 

12 

i5 

17 

20 

23 

26 

0,26 

14,671 

19 

14,690 

19 

14,709 

20 

14,729 

'9 

i4,748 

20 

14,768 

19 

0,0676 

3o 

3 

6 

9 
9 
10 

12 

i5 

18 

21 

24 

27 

0,27 

i5,235 

20 

i5,255 

20 

15,275 

20 

15,295 

30 

1 5,3 1 5 

30 

1 5,335 

20 

0,0729 

3i 

3 

6 

12 

16 

'9 

23 

35 

38 

0,28 

1 5,799 

20 

15,819 

21 

i5,84o 

21 

1 5,861 

21 

1 5,882 

31 

1 5,903 

21 

0,0784 

32 

3 

6 

i3 

16 

'9 

33 

36 

29 

0.29 

16,362 

22 

1 6,384 

22 

16,406 

32 

16,428 

21 

16,449 

32 

16,471 

21 

0,084 1 

33 
34 

3 
3 

7 
7 

10 
10 

i3 
i4 

17 
17 

30 
30 

33 

24 

36 

27 

3o 
3i 

o,3o 

16.926 

23 

16,949 

22 

16,971 

23 

16,994 

22 

17,016 

22 

i7,o38 

23 

o,ogoo 

0,3 1 

17,490 

24 

i7,5i4 

23 

17,537 

23 

17,560 

23 

17,583 

23 

17,606 

23 

0,0961 

35 

4 

7 

II 

i4 

18 

21 

25 

28 

33 

0,32 

i8,o54 

24 

18,078 

24 

18,102 

24 

18,126 

24 

i8,i5o 

24 

18,174 

23 

0,1024 

36 

4 

7 

II 

i4 

18 

23 

25 

29 

33 

0,33 

18,618 

25 

18,643 

24 

18,667 

25 

18,692 

25 

18,717 

24 

i8,74i 

25 

0,1089 

37 

4 

7 

II 

i5 

■9 

33 

26 

3o 

33 

0,34 

19,182 

25 

19,207 

26 

19,233 

25 

19,258 

25 

19,283 

26 

19,309 

35 

o,n56 

38 
39 

4 
4 

8 
8 

II 
12 

i5 
16 

'9 
20 

23 
23 

27 
27 

3o 
3i 

34 
35 

0,35 

19,746 

26 

19.772 

26 

19,798 

26 

19,824 

26 

i9,85o 

26 

19,876 

26 

0,1225 

32 

33 
34 

36 

37 
38 

o,36 

20,309 

27 

2o,336 

27 

2o,363 

27 

20,390 

37 

20.417 

27 

20,444 

27 

0,1296 

4o 

4 

8 

12 

16 

20 

24 
25 

28 

0,37 

3o'.873 

28 

20,901 

27 

20,928 

28 

20,956 

28 

2o',984 

27 

21,011 

38 

0,1389 

4i 

4 

8 

12 

16 

21 

29 

0,38 

21,437 

28 

21,465 

29 

2  '  ,494 

28 

21,522 

28 

2i,55o 

29 

21,57g 

38 

0,1 444 

42 

4 

8 

i3 

17 

21 

25 

19 

0,39 

22,000 

3o 

22,o3o 

29 

22,059 

29 

22,088 

29 

33,117 

29 

22,l46 

29 

0,l52I 

43 
44 

4 
4 

9 
9 

i3 
i3 

17 
18 

22 
22 

26 
26 

3o 
3i 

34 
35 

39 
40 

o,4o 
0,4 1 

22,564 
23,127 

3o 
3i 

22,594 

23,1 58 

3o 
3i 

22,624 
23,189 

3o 
3o 

23,654 
23,219 

3o 
3i 

22,684 

23,25o 

19 
3i 

22,7l3 

23,281 

3o 
3o 

0,1600 
0,1681 

45 

5 
5 
5 
5 
5 

9 

i4 

18 
18 

23 

23 

„  / 

27 
28 
28 

32 
32 

33 
34 
34 

36 

37 
38 
38 
39 

4i 

4i 
42 
43 
44 

0,42 

23,691 

3i 

23,722 

32 

23,754 

3i 

23,785 

32 

23,817 

3i 

23,848 

3i 

0,1764 

46 

9 

i4 
i4 

0,43 

24.254 

33 

24,287 

32 

24,319 

32 

24,35i 

32 

24,383 

32 

24,41 5 

32 

o,i84g 

47 

9 

19 

24 

24 

25 

0,44 

24,818 

33 

24,85i 

33 

24.884 

33 

24,917 

32 

24,949 

33 

24,982 

33 

0,1936 

48 
49 

10 
10 

i4 
i5 

19 
20 

29 
29 

0,45 

25.38i 

34 

25.4i5 

34 

25,44s 

33 

25,482 

34 

25,5i6 

33 

25.549 

34 

0,2025 

5o 
5i 

52 

53 
54 

5 

10 

i5 

20 

25 

3o 

35 

4o 

45 

o,5o 

28,197 

38 

28.235 

37 

28,272 

38 

28,310 

37 

28,347 

37 

28;384 

38 

o,35oo 

5 

10 

i5 

20 

26 

3i 

36 

4i 

46 

0,55 

3l,OI2 

42 

3i;o54 

4i 

3 1 ,095 

4i 

3i,i36 

4i 

3i,i77 

4i 

3i,2i8 

4r 

o,3o25 

5 

10 

16 

21 

26 

3i 

36 

42 

4-' 

0,60 

33,826 

45 

33,871 

45 

33,91c 

45 

33,961 

45 

34,006 

44 

34,o5o 

45 

o,36oo 

5 

16 

21 

27 
27 

32 

37 
38 

42 

48 

0,65 

36.638 

4g 

36,687 

48 

36,735 

49 

36,784 

49 

36,833 

48 

36,88 1 

49 

0,4335 

5 

I J 

16 

33 

33 

43 

49 

0,70 

39,448 

53 

39,501 

52 

39,553 

53 

39,606 

52 

39,658 

53 

39,711 

52 

0,4900 

55 

6 

II 

17 

32 

28 

33 

39 

44 

5o 

0,75 

42,257 

56 

42,3i3 

57 

42,37r 

56 

42,426 

56 

42,482 

56 

42,538 

56 

0,5625 

56 

6 

1 1 

17 

22 

38 

34 

39 

45 

5o 

0,80 

45,064 

6c 

45,124 

60 

45,18^ 

60 

45,244 

60 

45,3o4 

60 

45,364 

60 

o,64oo 

57 
58 

6 

1 1 

17 

23 

29 

34 

40 

46 

5i 

0,85 

47,868 

64 

47,932 

64 

47.99f 

64 

48,060 

64 

48,124 

63 

48,187 

64 

0,7335 

6 

12 

17 

23 

20 

35 

4i 

46 

52 

0,90 

50,671 

68 

50,739 

67 

5o,8oe 

68 

50,874 

67 

5o,94i 

68 

51,009 

67 

0,8100 

5g 

6 

12 

18 

24 

3o 

35 

4i 

47 

53 

0,95 

53,471 

-2 

53,543 

71 

53,6m 

72 

53,686 

71 

53,757 

71 

53,828 

71 

o,go25 

1,00 

56,26gl  70 

56,344 

75 

56,4191  76 

56,495 

75 

56,570 

75 

56,645 

75 

I 

,0000 

60 
61 
62 
63 

6 
6 
6 
6 

12 
12 
12 
i3 

18 
18 
19 
19 

24 
24 
25 
25 

3o 
3i 
3i 

32 

36 
37 
37 
38 
38 

41 
43 
43 
44 
45 

48 

5o 
5o 
5i 

54 
55 
56 
57 
58 

7,1065 

7,1442 

7,1821 

7,2200 

7,2581  1 

7,2962 

c2 

,^  .  (r  -f-  r"  ]^     or  r^ -\-  r"^     nearly. 

563 

564 

565 

566 

567 

568 

56g 

64 

6 

i3 

19 

26 

32 











— 

— 

65 

7 

i3 

20 

26 

33 

39 

46 

52 

59 

I 

56 

56 

57 

57 

57 

57 

57 

I 

66 

7 

i3 

20 

26 

33 

4o 

46 

53 

59 

2 

ii3 

ii3 

ii3 

1x3 

ii3 

ii4 

114 

2 

67 

7 

i3 

20 

27 

34 

40 

47 

54 

60 

3 

160 

,6g 

170 

170 

170 

170 

171 

3 

68 

7 

i4 

30 

27 

34 

4i 

48 

54 

61 

4 

225 

226 

226 

226 

227 

227 

228 

4 

69 

7 

i4 

31 

28 

35 

4i 

48 

55 

62 

5 

282 

282 

283 

283 

284 

284 

285 

5 

6 

338 

338 

339 

340 

340 

341 

34i 

6 

70 

7 

i4 

31 

28 

35 

42 

49 

56 

63 

7 

394 

395 

396 

396 

397 

398 

3o8 

7 

80 

8 

16 

24 

32 

40 

48 

56 

64 

72 

8 

45o 

45i 

452 

453 

454 

454 

455 

8 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

Q 

507 

5o8 

509 

509 

5io 

5ii 

5l2 

9 

100 

10 

20 

3o 

40 

5o 

60 

70 

80 

iS. 

TABLE  II.  —  To  find  the  time  T\  the  sum  of  the  radii  r -)-»■",  and  the  chord  c  being  given. 


Sum  of  the  Radii  r'\-r". 

Ciiord 
C. 

3,83 

3,84 

3,85 

3,86 

Days  Idif. 

3,87 

3,88 

3,89 

Days  Idif. 

3,90 

3,91 

3,92 

Days  |dir. 

Days  |dif. 

Days  idif. 

Days  Idif. 

Days  Idif. 

Daysjdif. 

Days  |dif. 

Days  |dif. 

0,00 
0,01 

0,02 
o,o3 
0,04 

0,000 
0,569 
i,i38 
1,706 
2,275 

I 
I 

3 
3 

0,000 
0,570 
1, 139 
1,709 
2,278 

0 
2 

2 

0 

0,000 
0,570 
I,l4l 
1,711 
2,281 

I 
I 
2 
3 

0,000 
0,571 
I,l42 
i,7i3 
2,284 

I 
2 
2 
3 

0,000 
0,572 
1. 144 
i,7i5 
2,287 

I 

I 

3 
3 

0,000 
0,573 

i,i45 
1,718 
2,290 

0 
2 
2 

3 

0,000 
0,573 

i,i47 
1,720 
2,293 

1 
I 
2 
3 

0,000 
0,574 
I,l48 
1,722 
2,296 

1 
2 
3 

0,000 
0,575 
1,1 5o 
1.724 
2,299 

0 

I 

3 

0,000 
0,575 

i,i5i 
1,726 

2,302 

I 
I 

3 

3 

0,0000 

0,000 1 
0,0004 
0,0009 
0,0016 

o,o5 
0,06 
0,07 
0,08 
0,09 

2,844 
3,4:3 
3,982 
4,55i 
5,119 

4 
4 
5 
6 

7 

2,848 
3,417 
3,987 
4,557 
5,126 

4 

c 

r 

7 

2,852 

3,422 
3,992 
4,562 
5,i33 

3 

4 
5 
6 
6 

2,855 
3,426 

3,997 
4,568 
5,139 

4 
5 
6 
6 
7 

2,859 
3,43 1 
4,oo3 
4,574 
5,i46 

4 
4 
5 
6 

7 

2,863 
3,435 
4,008 
4,58o 
5,i53 

3 
5 
5 
6 
6 

2,866 
3,440 
4,oi3 
4,586 
5,159 

4 
4 
5 
6 

7 

2,870 

3,444 
4,018 
4,592 
5,166 

4 
4 
5 
6 

7 

2.874 
3.448 
4,023 
4,598 
5,173 

3 
5 
5 
6 
6 

2,877 
3,453 
4,028 
4,604 
5,179 

4 
4 
5 
6 

7 

0,0025 

0,00  36 
0,0049 
0,0064 
0,0081 

0,10 
0,11 
0,12 
o,i3 

0,1 4 

5,688 
6,237 
6,826 
7,395 
7,963 

8 
8 
9 
9 
II 

5,696 
6,265 
6,835 
7>4o4 
7.974 

8 

9 
10 
.10 

5,7o3 
6,273 
6,844 
7,4 1 4 
7,984 

7 
8 
8 

9 
10 

5,710 
6.281 
6;852 
7.423 
7.994 

8 

I 
10 
II 

5,718 
6,290 
6,861 
7,433 
8,oo5 

8 

9 
10 
10 

5,725 
6,298 
6,870 
7.443 
8,oi5 

8 
8 
9 
9 
10 

5,733 
6,3o6 
6,879 
7.452 
8,025 

7 
8 

9 
10 
II 

5,74f 
6,3i4 
6,888 
7.462 
8,o36 

•-j 

8 

9 

9 

10 

5,747 

6,322 

6,897 

7,471 

8,046 

8 

8 

8 

10 

10 

5,755 

6,33o 
6,905 
7.481 
8,o56 

7 
8 

9 
9 
11 

0,0100 
0,0121 
0,0144 
0,0169 
0,0196 

o,i5 
0,16 
0,17 
0,18 
0,19 

8,532 
9,101 

io,238 
10,807 

II 
12 

1 3 
i3 
i4 

8,543 
9,ii3 
9,682 

IO,25l 

10,821 

II 

II 
i3 
i4 
i4 

8,554 
g,i24 
9.695 
10,265 
io,835 

II 
12 
12 
i3 
i4 

8,565 
9, 1 36 

9.707 
10,278 
10,849 

II 
12 
i3 
i3 
i4 

8,576 
9,148 
9.720 
10,291 
10,863 

12 
12 
12 

14 
i4 

8,588 
9,160 
9,732 
io,3o5 
10,877 

II 
12 

i3 
i3 

i4 

8,599 
9.172 
9.745 
io,3i8 
10,891 

II 
12 
12 
i3 
i4 

8,610 

9,184 

9.757 

io,33i 

10,905 

II 
11 
i3 

i4 
i4 

8,621 
9.195 
9.770 
10,345 

10,919 

II 
12 
12 
i3 
i4 

8,632 
9.207 
9,782 
io,358 
10,933 

n 
12 
i3 
i3 

i4 

0,02  25 

o,o256 
0,0289 
o,o324 
o,o36i 

0,20 
0,21 
0,22 
0,23 
0,24 

11,375 
11,944 
I2,5i3 
1 3,081 
i3,65o 

i5 
16 
16 

17 
18 

1 1 ,390 
1 1 ,960 
12,529 
i3,oq8 
i3,668 

i5 
i5 
16 

17 

17 

ii,4o5 
11,975 
12,545 
i3,ii5 
1 3,685 

i5 
16 

17 
17 
18 

11,420 
11,991 
12,562 
i3,i32 
1 3,703 

i5 
i5 
16 

17 
18 

11,435 
12,006 
12,578 
1 3,149 
i3,72i 

i4 
16 
16 

17 
18 

11,449 
12,022 
12,594 
i3,i66 
13,739 

i5 
i5 
16 

17 
17 

11,464 
i2,o37 
12,610 
i3,iS3 
i3,755 

i5 
16 

17 

17 
iS 

11.479 
i2,o53 
12,627 

l3,200 

1 3,774 

i5 
i5 
16 

17 
18 

11.494 
12,068 
12,643 

i3,2i7 
13,792 

i4 
16 
16 

17 
17 

ii,5o8 
12,084 
12.659 
i3;234 
13,809 

i5 
i5 
16 

17 
18 

o,o4oo 
0,044 1 
o,o484 
0,0529 
0,0576 

0,25 
0,26 
0,27 
0,28 
0,29 

14,218 
14,787 
i5,355 
15,924 
16,492 

19 
19 
20 
21 
22 

14,237 
14,806 
15,375 
1 5,945 
i6,5i4 

18 

19 
20 
20 
21 

i4,255 
14,825 
15,395 
15,965 
16,535 

'9 
20 
20 
21 
22 

14,274 
i4,845 
i5,4i5 
15,986 
16,557 

18 

19 
20 
21 
21 

14,292 
14.864 
i5,435 
16,007 
16,578 

19 

19 
20 
21 
22 

i4,3ii 
i4,883 
14.455 
16,028 
16,600 

18 

19 
20 
20 
21 

i4,329 
14.902 
14,475 
16,048 
16,621 

19 
20 
20 
21 
21 

14,348 
14,922 
15,495 
16,069 
16,642 

18 

19 
20 
20 
22 

1 4,366 
i4,94i 
i5,5i5 
16,089 
i6,664 

19 
19 
20 
21 
21 

i4,385 
14,960 
i5,535 
16,110 
1 6,685 

i8 

19 
20 
21 
21 

0,0625 
0,0676 
0,0729 
0,0784 
o,o84i 

o,3o 
o,3i 
0,32 
0,33 
0,34 

17,061 
17,629 
18,197 
18,766 
19,334 

22 

23 

24 
24 

25 

i7,o83 
17,652 

l8,22I 
18,790 
19,359 

22 

23 

24 

25 

26 

i7,io5 
17,675 
18,245 
i8,8i5 
19,385 

22 

23 

24 
24 

25 

17.127 
17,698 
18,269 
18,839 
19,410 

23 
23 
23 
25 
25 

i7,i5o 
17,721 
18,292 
18,864 
19,435 

22 

23 

24 
24 

25 

17.172 
17.744 
i8,3i6 
18,888 
19,460 

22 

23 

24 
24 

25 

17.194 
17,767 
18,340 
18,912 
19,485 

22 

23 
23 
25 
25 

17,216 

17.790 
1 8,363 
18,937 
19,510 

22 
22 
24 
24 

25 

17,238 
17.812 
18,387 
18,961 
19,535 

22 

23 
23 

24 

25 

17,260 
17,835 
18,410 
18,985 
19,560 

22 

23 

24 

25 
25 

0,0900 
0,0961 
0,1024 
0,1089 
0,1 1 56 

0.35 
o;36 
0,37 
o,38 
0,39 

19,902 
20,471 
2 1 ,039 
2 1 ,607 
22,175 

26 
26 

27 
28 
29 

19,928 
20,497 
2 1 ,066 

21,635 
22,204 

26 
27 
28 
28 
29 

19,954 
20,524 
2 1 ,094 
21.663 

22,233 

26 

27 
27 
29 
29 

19,980 
20,55 1 
21,121 
21,692 
22,262 

26 
26 
28 
28 
29 

20,006 
20,577 
21,149 
21,720 
22,291 

26 

27 
27 
28 
29 

20,o32 
20,604 
21,176 

21,748 
22,320 

26 

27 

27 
28 
28 

2o,o58 
20,63i 

2I,203 

21,776 
22,348 

26 

26 

27 
28 

29 

20,084 
20,637 

2I,23o 
21,804 
22,377 

25 

27 
28 

28 
29 

20,109 
20,684 

21,258 
21,832 

22,406 

26 
26 

27 
28 

29 

20,i35 
20,710 

21,285 

21,860 
22,435 

26 
26 

27 
28 
28 

0,1225 

0,1296 
0,1369 
0,1444 

0,l52I 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

22,743 
23,3ii 
23,879 
24,447 
25,01 5 

3o 
3i 
3i 

32 

33 

22,773 
23,342 
23,910 

24,479 
25,o48 

3o 
3o 

32 
32 
32 

22,8o3 

23,372 
23,942 
24,5ii 
25,080 

^9 
3o 

3i 

32 

33 

22,832 
23,402 
23,973 
24,543 

25,ii3 

3o 
3i 
3i 

32 

33 

22,862 
23,433 
24,004 
24,575 
25,i46 

'9 
3o 

3i 

3i 

32 

22,891 
23,463 
24,o35 
24,606 
25,178 

3o 
3o 
3i 

32 

33 

22,921 

23,493 

24,066 
24,638 

25,211 

^9 
3i 

3i 

32 
32 

22.950 

23,524 
24,097 
24,670 
25,243 

3o 
3o 
3i 

32 
32 

22,980 
23,554 
24,128 
24,702 
25,275 

29 

3o 
3i 
3i 
33 

23,009 
23,584 
24,159 
24.733 
25,3o8 

3o 
3o 
3o 

32 
'32 

0,1600 
0,1681 
0,1764 
0,1849 
0,1936 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

25,583 
28,422 
3i,259 
34,095 
36,93o 
39,763 

33 

37 
4i 
45 
48 

52 

25,616 
28,459 
3i,3oo 
34, 1 40 
36,978 
39,815 

34 
37 
4i 
44 
48 

52 

25,65o 
28,496 
3i,34i 
34,184 
37,026 
39,867 

33 

37 
4i 
45 

t 

25.683 
28;533 
3 1, 382 
34,229 
37.075 
39.919 

33 

37 
40 
44 
48 

52 

25,716 
28,570 

3l,422 

34,273 
37,123 
39.971 

34 
37 
4i 
45 
48 

52 

25,75o 
28,607 
3 1,463 
34,3i8 
37,171 

40,023 

33 

37 
4i 

48 

52 

25,783 

28,644 

3i.5o4 
34,362 

37.219 
40,075 

33 
37 
4o 
45 
48 
5i 

25,816 
28,681 
3 1, 544 
34,407 
37,267 
40,126 

33 

37 
4i 
AA 
48 

52 

25,849 
28,718 
31.585 
34,45i 
37,3 1 5 
40,178 

33 

37 
4o 
AA 
48 

52 

25,882 
28,755 
3i,625 
34,495 
37,363 
4o,23o 

33 
36 
4i 
AA 
48 
5i 

0,2025 

0,2  5oo 
o,3o2  5 
o,36oo 
0,4225 
0,4900 

0,75 
0,80 
0,85 
0,90 
o,g5 
1,00 

42,594 
45,424 
48,25i 
5 1 ,076 
53,899 
56,720 

56 

59 
63 

67 

71 
75 

42,65o 
45,483 
48,3 1 4 
5i,i43 
53,970 
56,795 

56 
60 
64 
68 

71 
75 

42,706 
45,543 
48,378 

5l,2II 

54,o4i 
56,870 

56 
59 
63 

67 
71 
74 

42,762 
45,602 
48 ,44 1 
51,278 
54,112 
56,944 

55 
60 
63 
67 
71 
75 

42,817 
45,662 

48,5o4 
5 1,345 
54,1 83 
57,019 

56 
5q 
63 
67 
71 
74 

42,873 
45,721 
48,567 
5i,4i2 
54,254 
57,093 

56 

66 

70 
75 

42,929 
45,780 
4S,63o 
51,478 
54,324 
57,168 

55 
60 
64 
67 
71 
74 

42,984 
45,840 
48,694 
5i,545 
54,395 
57,242 

55 

59 
62 

67 

70 
74 

43,039 
45,899 
48,756 
5i,6i2 
54,465 
57,3i6 

56 

59 
63 
66 

70 
74 

43,095 
45,958 
48,819 
51,678 
54,535 
57,390 

55 

1% 
67 
71 
74 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 

7,3345  1 

7,3728 

7,41131 

7,44981 

7,4885  1 

7,527:21 

7,5661 1 

7,6050 1 

7,6441 1 

7,68321 

i"" 

^  .  (r  +  '*")*  or  Î-"  -\-  r"~    nearly.                                         1 

568 

~1 
ii4 
170 
227 
284 
341 
398 
454 
5ii 


569 

57 
ii4 
171 
228 
285 
341 
398 
455 

5l2 


070 

57 

ii4 
171 
228 
285 
342 
399 
456 
5i3 


571 

572 

573 

574 

575 

576 

57 

57 

57 

57 

58 

58 

ii4 

ii4 

ii5 

ii5 

ii5 

ii5 

171 

172 

172 

172 

173 

173 

228 

229 

220 

23o 

23o 

23o 

286 

286 

287 

287 

288 

288 

343 

343 

344 

344 

345 

346 

400 

400 

4oi 

402 

4o3 

4o3 

457 

458 

458 

459 

460 

461 

5i4 

5i5 

5i6 

5i7 

5i8 

5i8 

TABLE  II. — TofinJ  the  time  T;  the  sum  of  the  radii  r-)-r",  and  tlie  chord  c  bcinp  given. 


Sum  of  tlie  Ra'iii  r-f-r". 


Choril 

c. 


0,00 
0,01 
0,02 
o,o3 
o,o4 

o,c5 
0,0(1 
0,07 
0,08 
o,og 

0,10 
0,1  I 
0,12 
0,1 3 
0,1 4 

0,1 5 
o,j6 
0,17 
0,18 
0,19 

0,30 
0,31 
0,23 
0,33 
0,24 

0,25 
0,36 
0,37 
0,28 
0.29 

o,3o 
0,3 1 

0,32 

0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
o,3g 

o,4o 
0,4 1 
0,43 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 
1. 00 


3,93 


Days  lilif 


0,000 
0,576 
l,l52 

1.7=9 
2,3o5 

2,88 1 

3,457 

4,o33 
4,610 
5,186 

5,762 
6.338 
6.9,4 
7,4il" 
8,067 

8,ti43 

9-"  y 
9,79:1 
10,371 
ro,947 

11,523 
12,099 
12,675 

l3,2  )I 

13,837 

r4,4o 

14,979 
15,355 
16,1  J 1 
16,706 

17,383 
17,858 
18,434 
19,010 
10,585 

20,l6l 

20,736 

3I,3l3 

21,888 

22,463 

23,039 
23,6i4 
24,189 
24,765 
35,340 

2J,Ql5 

28,791 

3 1, 666 
34,539 
37,411 
40,381 


43,130 
46,017 
48,882 
5 1, 74 5 
54,606  70 
57,4641  74 


3,94 


Days  |(iif. 


7,72: 


3.Î 


0,000 
0,577 
i,i54 
i,73i 
2,3o8 

2,885 
3,462 
4.039 
4,616 
5,193 

5,769 

6,346 

6.93 

7,5oo 

8,077 

8,654 

0,23  I 

5.807 

10, 384 
■  0.96 

11,538 
12,1 14 
12,691 
13.26S 
i3,84] 

i4>42i 
14,998 
1 5,5-5 
16,  i5i 
16,728 

i7,3o4 
17,881 
18,457 
'9,o34 
ig,6io 

20,187 
20.761 
21339 
21,913 
22.493 

23,068 
3  3,644 
24,220 
24,796 
25,372 

25.948 
28,838 
3r,7o6 
34,j83 
37,'i59 
4o,33r 

43,3oj 
46,076 
48,945 
5i,8ii 
54,676 
57,538 


3,95 


Days  |dir. 


7.7618 


1 1,332 

1  2 , 1 3o 

I2,70' 

1 3,285 
1 3,862 

i4,44o 
1 5,0 1 
15,594 
16,172 
if>,749 

17,326 
1 7,903 
18.481 
i9,o58 
19,635 

20,212 
20,789 
21.36b 

2  '  ,943 

22,320 

23,09' 
23,674 
24,331 
24,828 

25,4o5 

35.9S1 
28,865 
31,747 
34,627 
37,507 
4o,384 

43.260 
46;  1.35 
49.007 
5^878 
54,746 
57,612 


0,000 
0,578 
i,i55 
1,73. 

2,3l 

2.888 
3,466 
4,o44 
4,621 

5,199 

5,777 
6,354 
6,()32 
7,309 
8,087 


8,665 

9,242 

9,820 
10,3971   i3 
io,975|  i4 


3,96 


Days  liiif 


7,8013 


0,000 
0,378 

l,l57 

1,735 

2,3i4 

3,892 
3,470 
4,049 
4,637 
5,206 

5,784 
6,363 
6.941 
7,5i9 
8,097 

8,676 
9,254 
9,833 
io,4io 
■  0,989 

1 1 ,567 
12,145 
12,723 
i3.3o2 
1 3,S8o 

(4,458 
1 5,0 36 
1 5,61 4 
16,192 
16,7 

17,' 

17,926 

i8,5o4 

19,082 

19,660 

20,2.38 

20.816 

'  1^393 

31,971 
22,549 


23,704 
24,382 
34:839 
23,437 

26,014 
28,901 
31,787 
34,671 
37,554 
40,436 

43.3i5 
46,193 
49,070 
5 1,944 
54,816 
57,68') 


0,371^ 

1,138 

1,737 
2,3i7 

2.896 
3,-175 
4,o54 
4,633 
5,212 


3,791 
6,370, 

6,949     9 

7,328 

S,io8 


7,8408 


8,687 
9,366 

9,84 
10,434 

I  1  ,003 

11,582 
12,161 

12,739 

1 3,3 18 
1 3,897 

14,476 

13,03 

i5,63- 
i6,2i3 
16.79 

17,370 

17,949 
18,527 
19,106 
19,683 

30,263 
20,843 
21,420 

21,999 
22,57 

23.1 56 
23;734 

3.'<,3l3 

34,89 

35,469 

26,047 
28.938 

3 1, 83' 
34,71 5 
37,603 
40,487 

43,370 
46,252 
49,1 32 
32,010 
54,886 
57,759 


3,98 


0,0(K) 

o,58o 

I 

1,160 

I 

1 ,740 
2,319 

2 
3 

■-',899 

4 

3,479 
4,0  5(1 

5 
5 

4,639 
5,219 

6 
6 

5,799 
(i,378 

7 
8 

6,958 
7,538 

9 
9 

8,118 

10 

8,698 

10 

9,277 

12 

9,857 
10,437 

12 
i3 

i>,oi6 

i4 

11,596 

i5 

12.176 

i5 

12.733 

17 

1 3,335 

17 

13.9) 5 

17 

) 4,494 
)  5,074 

19 
19 

15.653 
16,233 
1 6,8 1 2 

17,392 
'7,971 
i8,55i 
i9,i3o 
19,710 

20,289 
30,868 

21,447 
22,027 
33,606 

33,i85 
33,764 
24,343 
24,923 
25,5oi 

36,080 
28,974 
31,867 
34,759 
37,649 
4o,538 

43,425 
46,3x1 
49,194 
53,076 
54,955 
57,833 


7,8805  I  7,9202 


0,0000 

0,tK)01 
0,0004 
0,0009 
0,0016 

0,0035 

o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,01 3 1 
0,01 44 
0,0169 
0,0196 

0,0335 
0,0256 
0,0389 
o,o324 
o,o36i 

o,o4oo 
0,044 1 
0,0484 
0,0529 
t),o576 

0,0625 
0,0676 
0,0729 
0,0784 
o,o84i 

0,0900 
0,0961 
0,1024 
0,1089 
0,11 56 

0,1225 
o,  1 296 
o,  1 369 
0,1 444 

0,l521 

0,1600 
0,1 68 1 
0,1764 
0,1849 
0,1936 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4335 
0,4900 

0,5635 
o,64oo 
0,7335 
0,8 1 00 
0,9025 
1 ,0000 

^2^ 


.  (  r  -f-  r  "  )  ^    or     r'^  -{-  r'  '^    nearly. 


373 

576 

577 

578 

579 

58o 

I 

58 

58 

58 

58 

58 

58 

I 

2 

113 

ii5 

ii5 

116 

116 

116 

2 

3 

173 

173 

173 

173 

174 

174 

3 

4 

23o 

23o 

33l 

23l 

232 

232 

4 

5 

388 

288 

389 

289 

390 

290 

5 

6 

345 

346 

346 

347 

347 

348 

6 

7 

4o3 

4o3 

4o4 

4o5 

4o5 

406 

7 

8 

460 

461 

462 

463 

463 

464 

8 

9 

5i8 

5(8 

5,9 

520 

521 

523 

0 

Proi».  \n\t\^  Inr  tln!  sum  uf  tliu  Uadii. 

.  I  2  I  3  I  4  I  5  I  6  I  7  I  8  I  9 


6 
6 
6 

7 
7  10 


1 1 


i&  21 
'9 


21 
16  21 
16  22  27 


22 


33 
23 

24 

35 

33  26 


24 

25 

26 
26 

27 

28 

3^ 
3o 
3i 

32 

33 
34 
34 
35 

36 

37 
38 
38 
39 

40 
41 
43 
43 
43 

44 
45 
46 
46 

47 

48 

t 
5o 
5i 

53 

53 
54 
54 


27 
28 

29 
3o 
3i 

33 
33 

33 
34 
35 

36 

37 
38 

39 
4o 

4i 
4i 
43 
43 

45 
46 
47 
48 

49 

5o 
5o 
5i 

52 

53 

54 
55 
56 
57 
58 

59 
59 
60 
61 
62 

63 


64  721 
73  81 
80I90I 


a15 


TABLE  II 

.  —  To  find  the  time  T 

;  the  sum 

3f  the  radii 

r-\-r",  and  the  chord  c  being 

given. 

Sum  of  the  Radii  r-\-r". 

Chord 
C. 

3,99 

4,00 

4,01 

4,02 

4,03 

4,04 

4,05 

1    4,06 

4,07 

4,08 

Days  |dif. 

Days  |dif. 

Days  |dif. 

Days|dif. 

Days  |dif. 

Days|dif. 

Days  |dir. 

Days  |dif.  1    Days  |d 

if.       Days  |dif. 

0,00 

0,00c 

0,00c 

0,00c 

) 

o,ooc 

0,00c 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,58i 

r 

o,58i 

o,58: 

I 

o,583 

c 

o,58: 

o,584 

1 

o,585 

I     0,586 

0    0,586 

I 

0,587 

I 

0,000 1 

0,02 

1,161 

3 

i,i63 

1 

1,164 

:; 

I,i6( 

1 

1,16- 

1 

1,168 

1,170 

I     1,171 

2     1,173 

I 

1,17^ 

2 

0,0004 

o,o3 

1,742 

2 

1,744 

i,74f 

s 

1,746 

i,75c 

1,753 

1,755 

2     1,757 

3     i,75g 

3 

1,761 

2 

0,0009 

0,04 

2,323 

3 

2,325 

- 

2,32fi 

- 

2,33i 

3,334 

C 

3,337 

'- 

2,340 

3     2,343 

3    2,346 

2 

3,348 

3 

0,0016 

o,o5 

2,90; 

4 

¥^ïl 

z 

2,910 

A 

3,qi4 

3,917 

A 

3,931 

A 

2,935 

3     3,g38 

4    2,932 

4 

2,936 

3 

0,0025 

0,06 

3,484 

4 

3,488 

A 

3,493 

5 

3,497 

4 

3,5oi 

A 

3,5o5 

c 

3,5io 

4     3;5i4 

4    3,5i8 

5 

3,523 

4 

o,oo36 

0,07 

4,064 

5 

4,069 

5 

4,074 

5 

4,079 

5 

4,084 

f 

4,090 

(; 

4,og5 

5    4,100 

5    4,io5 

5 

4,1 10 

5 

0,0049 
0,0064 

0,08 

4,645 

6 

4.65 1 

5 

4,656 

e 

4,662 

€ 

4,668 

6 

4,674 

ë 

4,680 

5    4,685 

6    4,691 

6 

4,697 

6 

0,09 

5,225 

7 

5,232 

e 

5,338 

7 

5,245 

6 

5,25i 

7 

5,358 

e 

5,364 

7     5,371 

6    5,277 

7 

5,284 

6 

0,0081 

0,10 

5,806 

7 

5,8 1 3 

7 

5,830 

8 

5,828 

7 

5,835 

7 

5,842 

7 

5,849 

8     5,857 

7    5,864 

7 

5,871 

7 

0,0100 

0,11 

6,386 

8 

6,394 

& 

6,4o2 

8 

6,4 10 

8 

6,4i8 

8 

6,426 

e 

0,434 

8    6,443 

8    6,45o 

8 

6,458 

8 

0,01 3 1 

0,12 

6,967 

9 

6,976 

8 

6,984 

9 

6,993 

9 

7,002 

8 

7,0 1  c 

6 

7,019 

9    7,038 

8    7,o36 

9 

7,045 

9 

0,01 44 

0,1.3 

7.547 

10 

7,557 

9 

7,566 

10 

7,576 

9 

7,585 

10 

7,595 

s 

7,604 

9    7>6i3 

lo     7,623 

9 

7,632 

9 

0,0169 

0,14 

8,128 

10 

8,i38 

10 

8,i48 

10 

8,i58 

II 

8,i6g 

10 

8,179 

10 

8,189 

10    8,199 

10    8,309 

IC 

8,219 

10 

0,01 96 

o,i5 

8,708 

II 

8,719 

II 

8,73o 

II 

8,74 1 

11 

8,752 

II 

8,763 

II 

8,774 

II     8,785 

10    8,795 

11 

8,806 

II 

0,0325 

0,16 

9,289 

12 

9,3oi 

1 1 

9,3 12 

12 

9,324 

1 1 

9,335 

13 

9,347 

13 

9,359 

II     9.370 

12     9,382 

II 

9,393 

12 

0,0256 

0,17 

9,8f>9 

1 3 

9,882 

13 

9,894 

12 

9,906 

i3 

9,919 

13 

9,931 

13 

9,943 

i3    9,956 

1 3     9,968 

13 

9,980 

12 

0,0289 

0,18 

io,45o 

i3 

io,463 

i3 

10,476 

i3 

10,489 

i3 

lO,502 

l3 

io,5i5 

l3 

10,538 

i3  io,54i 

1 3  i  0,554 

i3 

10,567 

i3 

o,o324 

0,19 

ii,o3o 

i4 

1 1 ,044 

14 

1 1  ,ù58 

i4 

1 1 ,072 

i3 

1 1  ,o85 

i4 

11,099 

14 

1 1,1 T 3 

i4  11,127 

i3  ii,i4o 

i4 

ii,i54 

14 

o,o36i 

0,20 

1 1 ,6 1 1 

i4 

11,625 

i5 

1 1 ,640 

i4 

1 1 ,654 

i5 

1 1 ,669 

i4 

11,683 

i5 

11,698 

i4  11,712 

i5  11,727 

i4 

II,74l 

i4 

o,o4oo 

0,21 

I3,igi 

i5 

12,206 

16 

12,322 

i5 

12,237 

i5 

13,353 

i5 

13,367 

16 

13,283 

1 5  13,298 

i5  i3,3i3 

i5 

13,338 

i5 

0,044 1 

0,22 

13,772 

16 

12,788 

16 

i3,8o4 

i5 

i2,8ig 

16 

12,835 

16 

1 3,85 1 

16 

13,867 

16  12,883 

16  13,899 

16 

I3,gi5 

16 

o,o484 

0,23 

i3,353 

17 

1 3,369 

16 

i3,385 

17 

l3,403 

17 

i3,4ig 

16 

i3,435 

17 

i3,452 

17  13,469 

16  i3,485 

17 

l3,S03 

16 

o,o53g 

0,24 

13,932 

18 

i3,g5o 

17 

13,967 

18 

13,985 

17 

l4,003 

17 

14,019 

18 

i4,o37 

17  i4,o54 

17  14,071 

18 

i4,o8g 

17 

0,0576 

0,25 

1 4,5 1 3 

18 

i4,53i 

18 

14.549 

18 

14,567 

18 

i4,585 

18 

i4,6o3 

18 

14,621 

18  i4,639 

18  i4,657 

18 

14,675 

18 

0,0625 

0,36 

i5,og3 

19 

l5,I  13 

19 

i5,i3i 

19 

i5,i5o 

i8 

1 5,168 

'9 

15,187 

19 

1 5,206 

ig  i5,325 

18  r5,343 

19 

15,363 

19 

0,0676 

0,27 

15,673 

20 

15,693 

'9 

i5,7i3 

30 

1 5,733 

20 

1 5,752 

19 

i5,77> 

30 

1 5,79 1 

19  i5,8io 

30  i5,83o 

19 

i5,84g 

19 

0,072g 

0,28 

16,253 

21 

16,274 

30 

i6,3q4 

30 

16,3 1 4 

2! 

16,335 

20 

i6,355 

30 

16,375 

30  i6,3g5 

21   i6,4i6 

30 

1 6,436 

20 

0,0784 

0,2g 

1 6,834 

31 

i6,855 

31 

16,876 

21 

16,897 

21 

i6,gi8 

21 

16,939 

21 

1 6,g6o 

21   16,981 

21   17,003 

31 

17,033 

20 

o,o84i 

o,3o 

I7,4i4 

22 

17.436 

21 

17,457 

33 

17,479 

33 

i7,5oi 

32 

17,533 

21 

17,544 

23   17,566 

33  17,588 

3! 

17,609 

22 

0,0900 

0,3 1 

17,994 

33 

18,017 

22 

i8,o39 

23 

18,063 

33 

18,084 

22 

iS,io6 

33 

i8,i2g 

33  i8,i5i 

23  18,174 

23 

i8,ig6 

32 

0,096 1 

0,32 

18,574 

33 

18,597 

24 

i8,62'i 

23 

18,644 

33 

18,667 

23 

i8,6go 

23 

18,7.3 

24  18,737 

23  18,760 

33 

1 8,783 

23 

0,1024 

0,33 

19,154 

34 

19,178 

24 

19,303 

34 

19,336 

34 

ig,3  5o 

24 

19,274 

24 

19,298 

24  19,322 

24  19,346 

33 

19,369 

34 

0,1089 

0,34 

19,734 

25 

19,759 

25 

19,784 

24 

19,808 

25 

19,833 

25 

19,858 

24 

19,882 

2  5  19,907 

24  19,931 

25 

ig,g56 

34 

0,1 1 56 

0,35 

20.3 1 4 

26 

20,340 

35 

20,365 

26 

3o,3gi 

25 

3o,4i6 

25 

3o,44i 

26 

20,467 

25  30,492 

35    20,5l7 

25 

20,543 

36 

0,1225 

o,36 

20,894 

27 

20,921 

26 

20,947 

36 

20,973 

26 

2o,qqq 

26 

21,025 

26 

2I,o5l 

26  21,077 

26  2i,io3 

26 

2i,i3g 

36 

0,1296 

0,37 

21,474 

37 

2 1, loi 

27 

31,538 

27 

31,555 

27 

21,582 

27 

21,609 

26 

21,635 

27  21,663 

27  21,689 

27 

21,716 

26 

0,1 369 

o,38 

2  2,o54 

38 

23,083 

28 

22,110 

27 

22,l37 

28 

22,l65 

27 

22,193 

28 

22,220 

27    32,247 

28  22,275 

27 

22.302 

37 

0,1 444 

0,39 

22,634 

29 

22,663 

28 

22,691 

28 

22,719 

29 

22,748 

28 

33,776 

28 

22,804 

28    22,832 

28  22,860 

28 

33,888 

39 

0,l52I 

0,40 

23,2l4 

?9 

33,243 

29 

33,273 

29 

33,3oi 

29 

23,33o 

29 

23,359 

20 

33,388 

29    23,417 

29  23,446 

29 

33,475 

39 

0, 1 600 

0,4 1 

33,794 

3o 

23,824 

3o 

23,854 

39 

23,883 

3u 

33,913 

3o 

23,943 

3Ô 

23,973 

29    24,002 

3o   24,o33 

39 

34,061 

3o 

0,1681 

0,42 

34,374 

3o 

24,404 

3i 

24,435 

3o 

24,465 

3i 

34,496 

3o 

34,536 

3i 

24,557   . 

ÎO  24,587 

3o  34,617 

3, 

24,648 

3o 

0,1764 

0,43 

24,954 

3 1 

24,985 

3i 

25,016 

3i 

25,o47 

33 

25,079 

3i 

25,110 

3i 

35,i4i 

jl     25,172 

3i  2  5,2o3 

3i 

35,334 

3i 

0,1849 

0,44 

25,533 

32 

25,565 

33 

3  5,5g7 

33 

35,62g 

32 

25,661 

33 

25,693 

32 

25,735 

32  25,757 

3 1  25,788 

32 

25,820 

33 

0,1936 

0,45 

26,113 

33 

26,146 

32 

26,178 

33 

36,311 

33 

36,344 

33 

26,276 

33 

36,309 

Î2    26,341 

33  26,374 

32 

36,406 

33 

0,3025 

o,5o 

29,011 

36 

29,047 

37 

3g,o84 

36 

29,120 

36 

39, 1 56 

36 

39,193 

37 

29,22g 

Î6  29,265 

36  29,301 

36 

29,337 

36 

0,2  5oo 

0,55 

31,907 

4i 

3 1, 948 

40 

31.988 

4o 

33,038 

39 

33,c)67 

4o 

33,107 

4" 

32,i47   ' 

io  32,187 

^0  32,237 

39 

32,266 

4o 

o,3o25 

0,60 

34,8o3 

ÂA 

34,847 

43 

34,890 

AA 

34,934 

AA 

34,978 

43 

35,021 

44 

35,o65   / 

13  35,108 

43  35,i5i 

44 

35,195 

43 

o,36oo 

o,65 

37,697 

47 

37,744 

48 

37,792 

47 

37,839 

47 

37,886 

47 

37,933 

47 

37,980   t 

iS  38,028 

il  38,075 

46 

38,121 

47 

0,4335 

0,70 

40,589 

5i 

4o,64o 

5i 

40,691 

5i 

40,742 

5i 

40,793 

5i 

40,844 

5i 

40,895 

ji  40,946 

5o  40,996 

5i 

4i,o47 

5o 

o,4goo 

0,75 

43,480 

55 

43,535 

55 

43,590 

54 

43,644 

55 

43,699 

54 

43,753 

55 

43,808 

54  43,862 

54  43,916 

55 

43,971 

54 

o,5635 

0,80 

46,369 

59 

46,438 

58 

46,486 

58 

46,544 

59 

46,6o3 

58 

46,661 

58 

46,719 

58  46,777 

58  46,835 

58 

46,Sg3 

58 

c,64oo 

o,85 

49,357 

62 

49,319 

63 

49,38i 

62 

49,443 

62 

4q,5o5 

62 

49,567 

61 

49,628   ( 

32    49,690     ( 

33  49,753 

61 

4g,8i3 

62 

0,7225 

0,90 

52, 142 

66 

52,308 

65 

53,273 

66 

53,339 

66 

5i,4o5 

65 

52,470 

66 

53,536   ( 

55  52,601    ( 

55  52,666 

66 

52.732 

65 

0,8100 

0,95 

55,035 

70 

55,095 

69 

55,164 

69 

55,333 

70 

55,3o3 

69 

55,372 

69 

55,441    ( 

39  55,5io 

59  55,579 

69 

55,648 

69 

0,9025 

1,00 

57,906 

73 

57,979 

73 

58,o52 

73 

58,125 

73 

58,198 

73 

58,271 

73 

58,344   • 

73  58,4 17 

73  58,490 

72 

58,562 

73 

1 ,0000 

7,9601 1 

8,0000  1 

8,0401 1 

8,0802 1 

8,12051 

8,16081 

8,201. 

3    8,241 

3    8,28251 

8,3232  1 

c2 

\  .  {r  •\-  r")'^     or    r^  +  r"'   nearly.                                                                                                      | 

579 

58o 

58 1 

582 

583 

584 

585 

586 

587 

588 

I 

58 

58 

58 

58 

58 

58 

~9 

~59 

"59 

"5^ 

I 

2 

116 

116 

116 

116 

117 

117 

117 

117 

117 

118 

a 

3 

174 

174 

174 

175 

175 

175 

176 

-     176 

176 

176 

3 

4 

233 

332 

333 

233 

233 

334 

234 

234 

235 

235 

4 

5 

390 

290 

391 

2qi 

392 

392 

293 

2q3 

294 

294 

5 

6 

347 

348 

349 

349 

35o 

35o 

35i 

352 

352 

353 

6 

7 

4o5 

406 

407 

407 

408 

409 

4io 

4io 

4ii 

4l2 

7 

8 

463 

464 

465 

466 

466 

467 

468 

469 

470 

470 

8 

9 

r 

21 

5 

32 

c 

23 

5 

241 

5 

35   1 

5: 

6  1 

527 

537 

528 

529 

9 

TABLE  II.  - 

To  find  the  time  T; 

the  sum 

of  the  rad 

ir  +  , 

",  and  th 

e  chord 

c  being 

given. 

Sum  ot"  the  Kaihi  r-\-r'\                                                                    | 

Prop,  parts  lur  the  sum  of  the  Kadii.    i 
.  1  ^  1  J  1  /I  r,  1  /;  1  -,  I  i;  1  ^  1 

ChorJ 

c. 

4,09 

4,10 

4,11 

4,1-2 

4,13 

4,14 

I  1  2  1  J  1  4  1  J  1  6  1  7  1  8  1 

y. 

1 
2 
3 

0 

0 
0 

0 

I 
I 

0 

1 

I 
I 

2 

1 

I 
2 

1 
I 
3 

I 
2 
2 

I 
2 
3 

Days  |dif. 

Days  |dif. 

Days  Idif. 

Duya  |dir. 

Uays  |dir. 

Days  |dif. 

0,00 

0,000 

0,000 

o,o<  )0 

0,000 

0,000 

OjOOt.) 

<.),ouoo 

0,01 

o,58« 

I 

0,589 

0 

0,589 

I 

0,590 

I 

0,591 

0 

0,591 

I 

<.),0l.i01 

4 

1 

3 

2 

2 

3 

3 

4 

0,02 

1,17(1 

1 

1. 177 

2 

1. 1 -9 

I 

1,180 

I 

1,181 

2 

I,i83 

1 

0,0004 

o,o3 

1,763 

3 

1,766 

2 

1,768 

2 

1.770 

2 

..773 

2 

1,774 

2 

0,0009 

5 

2 

2 

3 

3 

4 

4 

5 

o,o4 

2,35i 

3 

2.354 

3 

2.357 

3 

2,36o 

0 

2,363 

3 

2,366 

2 

0,0016 

6 

7 

2 
2 

2 
3 

3 
4 

4 
4 

4 
5 

5 
6 

5 
6 

o,o5 

2,939 

4 

2,943 

3 

2,946 

4 

2,950 

3 

2,953 

4 

2,957 

4 

0,0025 

8 

2 

2 

3 

4 

5 

6 

6 

7 

0,06 

3.527 

4 

3,53 1 

5 

3,536 

4 

3,540 

4 

3,544 

4 

3,548 

5 

o,oo36 

9 

2 

3 

4 

5 

5 

6 

7 

8 

0,07 

4,ii5 

5 

4,120 

5 

4.125 

5 

4,i3o 

5 

4,i35 

5 

4,i4o 

5 

0,0049 

10 

2 

3 

4 
4 

5 

5 

f, 

7 
8 

8 

9 
10 

0,08 

4,7o3 

5 

4,708 

6 

4,714 

6 

4,720 

5 

4,725 

6 

4,73 1 

6 

0,0064 

2 

3 

fi 

7 
7 

9 
10 

0,09 

5,290 

7 

5,297 

6 

5,3o3 

7 

5,3io 

6 

5,3i6 

7 

5,323 

6 

0,008 1 

12 

2 

4 

() 

8 

1 1 

0,10 

5,8-8 

- 

5,885 

7 

5,892 

8 

5,900 

7 

5,907 

7 

5,914 

7 

0,0100 

i3 
i4 

3 
3 

4 

5 
6 

7 
7 

8 
8 

9 
10 

10 
1 1 

12 
i3 

0,11 

6,466 

S 

6,474 

8 

6,482 

8 

6,490 

7 

6,497 

8 

6,5o5 

8 

0,01  3  I 

0,12 

7,o54 

8 

7,062 

9 

7,071 

8 

7.079 

9 

7,088 

9 

7,097 

8 

0,0.44 

i5 

2 

3 

5 

6 

8 

9 

11 

12 

.4 

o,i3 

7,64 1 

10 

7,65 1 

9 

7,660 

9 

7,669 

10 

7,679 

9 

7,688 

9 

0,0169 

16 

2 

3 

5 

6 

8 

10 

II 

i3 

.4 

o,i4 

8,229 

10 

8,239 

10 

8,249 

10 

8,259 

10 

8,269 

10 

8,279 

10 

0,0196 

17 
18 

2 
2 

3 

4 

5 
5 

7 
7 

9 
g 

10 
II 

12 

i3 

i4 
■  4 

i5 
16 

0,1^1 

8,8 1- 

II 

8,828 

10 

8,838 

11 

8,849 

II 

8,860 

II 

8,871 

10 

0,033  5 

■9 

2 

4 

6 

8 

10 

II 

i3 

i5 

.7 

0,16 

9,4o5 

II 

9,416 

12 

9.428 

II 

9,439 

12 

9,45 1 

I. 

9,462 

11 

o,o256 

16 

18 

0,17 

9.993 

i3 

io,oo5 

12 

10,017 

12 

10,029 

12 

io,o4i 

12 

io,o53 

12 

0,0289 

20 

2 

4 

6 

8 

10 

12 

.4 

0,18 

io,58o 

i3 

10,593 

i3 

10,606 

i3 

io,6ig 

i3 

io,632 

12 

10,644 

i3 

o,o334 

21 

2 

4 

6 

8 

II 

i3 

i5 

'7 

•9 

0,19 

11,168 

.3 

11,181 

i4 

11,195 

.4 

11,209 

i3 

11,222 

i4 

1 1 ,236 

i3 

o,o36i 

22 

23 

2 
2 

4 
5 

7 

7 

9 
9 

II 
12 

i3 
i4 

i5 
16 

18 
18 

20 
21 

0,50 

.1,735 

i5 

11,770 

i4 

11,784 

i4 

11,798 

i5 

ii,8i3 

i4 

11,827 

.4 

o,o4oo 

24 

3 

5 

7 

10 

12 

i4 

'7 

19 

22 

0,21 
0,22 

13,343 
12,931 

.5 
i5 

12,358 
12,946 

i5 
16 

12,373 
12^62 

i5 
16 

12,388 
12,978 

i5 
16 

1 2,4o3 
12,994 

i5 
i5 

12,418 
13,009 

i5 
16 

0,044 1 
0,0484 

25 

26 

3 
3 

5 
5 
5 
6 

8 
8 
8 
8 

10 

i3 
i3 

i5 
16 

18 
18 

20 

23 
23 

0,23 

i3,5i8 

■7 

i3,535 

16 

1 3,55 1 

17 

1 3,568 

16 

1 3,584 

17 

i3,6oi 

16 

0,0529 

3 
3 

10 

i4 
i4 

16 

24 

25 

0,24 

i4,io6 

17 

i4,i23 

17 

i4,i4o 

18 

i4,.58 

17 

14,175 

17 

14,192 

17 

0,0576 

27 

28 

1 1 

1 1 

17 

19 
30 

22 

0,25 

14,693 

18 

14,711 

18 

i4,72<) 

iG 

.4,747 

18 

14,765 

18 

14,783 

18 

0,0625 

29 

3 

6 

9 

12 

i5 

.7 

30 

23 

26 

0,26 

1 5,281 

'9 

i5,3oo 

18 

i5,3i8 

'9 

1 5,337 

'9 

1 5,356 

18 

.5,374 

19 

0,0676 

3o 

3 

6 

9 
9 
10 

12 

i5 

18 

21 

24 

27 

0,27 

1 5,868 

20 

1 5,888 

19 

15,907 

20 

.5,927 

■9 

1 5,946 

19 

15,965 

20 

0,0739 

3i 

3 

6 

12 

16 

'9 

22 

25 

28 

0,28 

16,4  56 

20 

16,476 

20 

16,496 

20 

i6,5i6 

20 

1 6,536 

20 

1 6,556 

20 

0,0784 

32 

3 

6 

i3 

16 

'9 

22 

26 

29 

0,29 

17,043 

21 

17,064 

21 

i7,o85 

21 

17,106 

21 

17,127 

20 

17,147 

21 

0,084 1 

33 
34 

3 
3 

7 
7 

10 
10 

i3 
i4 

.7 
17 

30 
20 

23 

24 

26 

27 

3o 
3i 

o,3o 

i7,63i 

21 

17,652 

22 

17.674 

21 

17,695 

22 

17,7.7 

21 

17,738 

22 

0,0900 

0,3 1 

18,218 

23 

18,241 

22 

1 8.363 

23 

i8,285 

22 

18,307 

22 

18,329 

23 

0,096 1 

35 

4 

7 

II 

i4 

18 

21 

25 

28 

32 

0,32 

i8,So6 

23 

18,829 

23 

i8,852 

23 

18,875 

23 

18,897 

23 

18,920 

23 

0,1034 

36 

4 

7 

II 

.4 

18 

22 

25 

29 

32 

0,33 

19,393 

24 

.9>4i7 

23 

19,440 

24 

19.464 

24 

1 9,488 

23 

19,51 1 

24 

o,io8g 

37 

4 

7 

11 

i5 

■9 

33 

26 

3o 

33 

0,34 

19,980 

25 

20,005 

24 

20,029 

25 

2o,o54 

24 

20,078 

24 

20,102 

25 

0,11 56 

38 
39 

4 
4 

8 
8 

II 
12 

i5 
16 

19 
20 

23 
23 

27 
27 

3o 
3i 

34 
35 

0,35 

2o,568 

25 

20,593 

25 

20,618 

25 

20,643 

25 

20,668 

25 

20,693 

25 

0,I335 

32 

36 

37 
38 

39 
40 

0,36 

2i,i55 

26 

21,181 

26 

21,207 

25 

21,232 

26 

21,358 

26 

21,284 

26 

o,i3g6 

40 

4 

8 

12 

16 

20 

24 

28 

0,37 

21,742 

27 

21,769 

26 

21,795 

27 

21,822 

26 

2 1 ,848 

27 

21,875 

26 

0,1369 

4i 

4 

8 

12 

16 

21 

25 
25 

29 

33 
34 
34 
35 

0,38 

22,329 

28 

22,357 

27 

2  2,384 

27 

92,4ll 

27 

22,438 

28 

2  2,466 

27 

o,t444 

43 

4 

8 

i3 

17 

31 

=9 

0,39 

22,917 

28 

22,945 

98 

22,973 

28 

23,001 

28 

23,039 

27 

23,o56 

28 

0,l521 

43 
44 

4 
4 

9 
9 

i3 
i3 

17 
18 

33 
22 

26 

26 

3o 
3i 

o,4o 

23,5o4 

28 

23,532 

29 

23,56i 

29 

23,590 

29 

23,619 

28 

23,647 

=9 

0,1600 

45 
46 

5 

T  /, 

18 
18 

23 
33 
24 
24 
25 

32 
32 

33 
34 
34 

36 

37 
38 
38 
39 

4i 
4. 
42 
43 
44 

0,4  r 

24,091 

29 

24,120 

3o 

24,1 5o 

29 

24,179 

3o 

24,209 

'9 

24,238 

29 

0,1681 

5 
5 
5 
5 

9 

14 

i4 
i4 
i4 
i5 

27 

28 
28 

0,42 

24,678 

3o 

24,708 

3o 

24,738 

So 

24.768 

3o 

24,798 

3i 

24,829 

3o 

0,1764 

9 

0,43 

25,265 

3i 

25,296 

3i 

25,327 

3i 

25.358 

3< 

25,388 

3i 

25,419 

3i 

0,1849 

47 

9 

'9 

0,44 

25,852 

32 

25,884 

3i 

25,9.5 

32 

25,947 

3i 

25,978 

32 

26,010 

3i 

o,ig36 

48 
49 

10 
10 

19 
20 

29 
29 

0,45 

26,439 

32 

26,471 

33 

26,504 

32 

26,536 

32 

26,568 

32 

26,600 

32 

0,3025 

5o 

5 

If» 

1 5 

20 

25 

3o 

35 

40 

45 

o,5o 

29,373 

36 

29,409 

36 

29,445 

36 

29,481 

36 

39,5.7 

35 

3g,552 

36 

o,35oo 

5i 

5 

10 

i5 

30 

26 

3i 

36 

4i 

46 

0,55 

32,3o6 

4o 

32,346 

39 

32,385 

40 

32,425 

3g 

32,464 

4( 

32,5o4 

39 

o,3o35 

52 

5 

10 

16 

31 

26 

3i 

36 

42 

47 

0,60 

35,238 

43 

35,281 

43 

35,324 

43 

35,367 

43 

35,410 

43 

35,453 

43 

o,36oo 

53 

5 

1 1 

16 

31 

27 
27 

32 

37 
38 

42 

48 

o,65 

38, 168 

47 

38,2i5 

47 

38,262 

47 

38,3o9 

4C 

38,355 

47 

38,4o2 

46 

0,4225 

54 

5 

1 1 

16 

22 

32 

43 

49 

0,70 

41,097 

5i 

4.,i48 

5o 

41,198 

5i 

41,249 

5o 

41,29g 

5o 

41,349 

5o 

0,4900 

55 

6 

II 

17 

22 

28 

33 

39 

44 

5o 

0,75 

44,025 

54 

44,079 

54 

44,i33 

54 

44,187 

54 

44,241 

54 

44.295 

53 

0,5625 

56 

6 

II 

17 

32 

28 

34 

39 

45 

5o 

0,80 

46,95 1 

57 

47,008 

58 

47,066 

58 

47,124 

5- 

47,. 8. 

58 

47,239 

57 

0,64*10 

57 

6 

II 

17 

23 

29 

34 

4o 

46 

5i 

0,85 

49,875 

61 

49.936 

61 

49,997 

62 

5o,o59 

61 

5o,i2o 

61 

5o,i8i 

61 

0,7225 

58 

6 

12 

.7 

23 

29 

35 

4i 

46 

52 

0,90 

52,797 

65 

52,862 

65 

52,927 

65 

52,992 

64 

53,o56 

65 

53,121 

65 

0,8100 

59 

6 

12 

18 

24 

3o 

35 

4. 

47 

53 

0,95 

55,7.7 

68 

55,785 

69 

55,854 

69 

55,923 

6t 

55,991 

68 

56,o59 

69 

0,9025 

1,00 

58,635 

72 

58,707 

72 

58,779 

72 

58,85i 

73 

58,924 

72 

58,996 

7. 

I 

,0000 

60 
61 
62 
63 
64 

6 
6 
6 
6 
6 

12 
12 
12 
i3 
i3 

18 
18 
19 
19 

24 
24 
25 
35 
26 

3o 
3 1 
3i 

32 
32 

36 
37 
37 
38 
38 

42 
43 
43 
44 
45 

48 

49 
5o 
5o 
5i 

54 
55 
56 
57 
58 

8,3641 

8,4050 

8,4461 

8,4872 

8,5285 

8,5698 

"  C^ 

^  .  (r  +  r")=^  or  r^-^  r"'^     nearly. 

587 

588 

589 

590 

5g< 

592 

.9 



— 





— 

65 

7 

i3 

20 

26 

33 

3g 

46 

52 

59 

I 

59 

59 

59 

59 

^§ 

59 

I 

66 

7 

i3 

20 

26 

33 

40 

46 

53 

59 

1 

117 

118 

118 

118 

118 

118 

2 

67 

7 

1 3 

20 

37 

34 

4o 

47 

54 

60 

3 

176 

176 

177 

177 

177 

178 

3 

68 

7 

i4 

20 

27 

34 

4i 

48 

54 

61 

4 

235 

235 

236 

236 

236 

237 

4 

69 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

5 

294 

294 

2g5 

295 

296 

296 

5 

6 

352 

353 

353 

354 

355 

355 

6 

70 

7 

i4 

21 

28 

35 

42 

49 

56 

63 

7 

4ii 

4l2 

4l2 

4i3 

4i4 

4i4 

7 

80 

8 

16 

24 

32 

4o 

48 

56 

64 

72 

8 

470 

470 

471 

472 

473 

474 

8 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

9 

528 

529 

53o 

53i 

532 

533 

9 

100 

10 

20 

_3o_ 

4o 

5o 

60 

70 

80 

9^ 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-\-r",  and  the  chord  c  being  given. 

ISutn  of  tlie  Radii  r  -\-  t". 


Chord 
C. 


0,00 
0,01 
0,02 

o,o3 
o,o4 

o,o5 
0,06 
0,07 

0,08 
0,09 


0,1 3 
o,i4 

0,1 5 
o,t6 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 
0,23 

0,24 

0,25 
0,26 
0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 


4,1.5 


Days  |<lir. 


0,000 
0,592 
1,184 
I,77f' 
2,368 

2, 961 

3,553 
4,i45 
4,737 
5,32g 

5,921 
6,5 1 3 
7,io5 

7,697 
8,289 

8,881 

9:473 

io,o65 

10,657 

11,249 

ii,84i 
12,433 
1 3,025 
13,617 
14,209 

i4,8oi 
15,393 
1J.985 
16,576 
17,168 

17,760 
18,352 
18,943 
19,535 
20,127 

20,718 
a  1 ,3 1  o 
2i,goi 
22.^93 
23,084 

23,676 
24,267 
24,859 
25,i5o 
26,041 

26,633 
29,588 
32,543 
35,496 
38,448 
41,399 

44,348 
47,296 
50,242 
53,r86 
56,128 
59,067 


4,1(5 


Days  |dir, 


8,611:3 


0,000 
0,593 
1,186 
1,778 
2,371 

2,964 
3,557 
4,i5o 
4,743 
5,335 

5,928 
6,521 
7,1'^ 
7,707 
8,299 

8,892 

9,485 

1 0,078 

10,670 

11,263 

11.856 
12,448 

1 3,633 
14,226 

14,819 
i5,4ii 
16,004 
16,596 
17,189 

17,781 
18,37-1 
18,966 
19,558 

20,l5l 

20,743 
21,335 
21,928 
22,520 
a3,ii2 

23,704 
24,296 
24.88g 
25,48 1 
26,073 

26,665 
29,624 
32,583 
35,539 
38,495 
41,449 

44,402 
:Î7,353 
5u,3o3 
53,25o 
56,196 
59. '39 


4,17 


Days  III  if. 


8,6528 


0,000 
o,5g4 

1,187 
1,781 
2,374 

2,968 

3,56i 
4,i55 

4,748 
5,342 

5,935 
6,539 
7,122 
7,716 
8,3og 

8,903 

9>49'5 
10,090 
1 0,68  i 
11,276 

17,870 
1  2,46-; 
1 3,007 
i3,65o 
14,243 

1  4,836 
r5,4;'o 

1 6.02  ■; 

^6:616 

17,209 

17.803 
18,396 

18,989 
19,583 
20,175 

20,768 
3i,36i 
21,954 
22,547 
23,i4o 

23,733 
24,326 
24,918 
25, 5i  I 
26,ioi 

26,697 
29,660 
32,621 
35,582 
38,541 
41=499 

,456 
47,4ii 
5o,364 
53,3i5 
56,264 
59,21 1 


4,18 


Days  |dif. 


8,6945 


0,000 

0.59. 

li'Sg 

1,783 

2,377 

2,971 
3,566 
4,160 
4,7'i4 
5,348 

5,943 
6,537 
7,i3i 
7,725 
8,3)9 

8,913 

9,5oS 

10,102 

10,696 

1 1 ,290 

11,884 
12,478 
1 3,072 
1  3,666 
14,260 

i4,85 
1 5,44s 
i(i,o42 
1 6.636 
(7, 230 

17,82 

i8,4i8 

19,012 

19,605 

20,199 

20,793 
2i,3S7 
2 1 ,980 

22,374 
23,168 

23,761 
24,355 
24,948 
25,542 

26, 1 35 

26,72g 
29,695 
32,661 
35.625 
38,588 
41,549 

44,5oq 
17,468 
5o,  124 
53,379 
56.332 
59,283 


4,19 


Days  |.lif. 


8,7362 


0,000 
0,595 

i,igo 

1.785 
2,3So 

2,975 
3,570 
4,i65 
4,760 
5,355 

5,g5o 
6,j44 
7,1 39 
7,734 
8,329 

8,924 

9,519 

io,ii4 

10,709 

ii,3o3 

11,898 
12,493 
i3,oS8 
i3,68J 

'4,277 

14,872 
15,467 
i6.o(i 
1 6,656 
'7,25i 

17,845 
i8,4':o 
19,034 
19.629 

20;223 

20,818 
2l,4l2 
23,007 

2  2,(j<Ji 
ai, 195 

23,790 

3 4,38 < 
2'î,978 
25,572 
36,167 

26,76 1 
29,731 

3  a. 700 
35/568 
38,634 
41,59g 

44,563 
47,525 
50.485 
53,fi3 
56,  -lOO 
59.354 


4,20 


Days  ]dif. 


26 


38 


8,7781 


0,000 

o,5g6 
1,191 
1,787 
2,383 

2,978 
3,574 
4,170 
4,765 
5,36i 

5,957 
6,552 
7,148 

7.744 

8,339 
8,935 

9,53o 
10,126 
10,721 
ii,3i7 

ii,gi2 
i2,5o8 
i3,io3 
13,69g 
14,294 

1 4.8go 
1 5,485 
16.0S1 
1 6,676 
17,271 

1 7,867 

18,462 

19,057 

19,65 

ao,248 

20,843 
31,438 

22,033 

32,628 
33,233 

23.818 

24.<l3 

25,008 
3  5,6o3 
26,198 

26,793 
29,766 

3 ',739 
35.710 
38.680 
4 1,649 

44,616 
47.532 
5o,546 
53,5oS 
56,468 
5g,l26 


4,21 


Days  |dif. 


0,000 
o,5g6 
1,193 

',789 
3,386 

2,982 
3,578 
4,175 
4,77' 
5,367 

5,96 
6,56o 
7,1 56 

7,753 
8,349 

8,g45 
9,542 
io,i38 
10,734 
ii,33o 


1 5  11,927 
i5  13,533 


8,8200 


i3,i  19 
13.71J 
i4|3ii 

1 4,908 

1  5,5o4 
1 6, 1 00 
16,696 
17,292 

17,888 
18,484 
19,080 
19,676 
20,272 

20,868 
2i,,|63 
22,059 
22,655 
23.r!5l 

23,847 
24,442 

2  5,0)8 
a  5,634 
26.22g 

26,825 
20.802 

32,778 
35,753 
38,727 
41,699 

44,670 
47,639 
5o,6o6 
53,5-2 
56,536 
30,497 


4,22 


Days  Idil'. 


8,8621 


0,000 
0,597 
1,194 
1,791 

2,388 

a.985 
3,583 
4,180 

4,777 
5,374 

5,971 
6,568 
7,1 65 
7,762 
8,359 

8,956 

9,553 

io,i5o 

10,747 

",344 

11,941 
13,538 
1 3,i35 
1 3,732 
14,328 


4,23 


Days  |dir. 


0,000 
0,598 
r ,  I  g6 

1,793 
2,391 

2,989 
3,587 
4,i85 
4,782 
5,38o 

5,978 
6,576 
7,173 
7,77' 
8,36g 

8,967 

9.564 

10,162 

10,760 

11,357 

11,955 
12,553 
i3,i5o 
1 3,74s 
14,345 


14,925 

18 

'4,943 

.8 

1  3.323 

lb 

13,540 

IQ 

io,i  19 

19 

i6,i38 

IQ 

16,710 

10 

16,735 

20 

17,3l2 

21 

17,33; 

20 

'7.909 

21 

17,930 

aa 

i8,3ob 

22 

18,528 

22 

19.103 

22 

19,125 

23 

19,699 

23 

19,722 

24 

20,396 

24 

20,320 

21 

20,893 

2  5 

20,917 

23 

2i,4Sa 

2J 

2i,5i4 

26 

32.083 

27 

22,113 

26 

3 a. 68 a 

27 

22,709 

27 

23,278 

38 

23,3o6 

28 

23,875 

28 

2  3-ooj 

aq 

2  (.471 

2Q 

34.300 

aq 

25.068 

29 

23,097 

3o 

3  5,664 

3o 

35.694 

3/ 

26,2(X) 

3i 

36,291 

3? 

26,85- 

3i 

26.8S8 

32 

29,837 

36 

29;S73 

33 

32,8.7 

39 

32  856 

3q 

33,795 

a 

35,838 

Â2 

38,773 

46 

38,819 

46 

41,749 

49 

41,798 

30 

44:733 

53 

44.776 

53 

47,6{j6 

56 

47.7" 

37 

50,6(17 

60 

30,727 

60 

53,636 

64 

53.700 

64 

56,6o3 

68 

36,671 

67 

5g,i68 

72 

39,640  71 

8,9465 

8,90 

12 

4,24 


Days  Idif. 


0,000 
0,598 

','97 
1,796 
2,394 

2,993 
3,591 
4,190 
4,788 
5,386 

5,c 

6,583 

7,183 

7,780 

8,379 

8«77 
9,576 
10,174 
10,773 
11,371 

"«69 
12.567 
1 3, 1 66 
1 3,764 
i4,362 

14,961 
1 5,559 
16,137 
16.755 
17,353 

r7,o52 
i8,53o 

'9:' 

'9.746 
20,344 

20,942 
21,540 

22,l38 

2  2,736 
23,334 

23,932 
24,52g 
25,127 
25.725 
26,323 

36,930 
29,908 
32,893 
35,880 
38,865 
4 1,848 

'14,829 
47.809 
30,787 
53,764 
56,738 
59,7" 


0,0000 
0,0001 
o,ooo4 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
0,0064 
0,008 1 

0,0100 
0,0121 
0,0 1 44 
o,oi()g 
0,0196 

0,0235 
0,02 56 
0,0389 
o,o324 
o,o36i 


r4  o,o4oo 
1 5  o,o44' 
0,0484 
0,0529 
0,0576 


8,9888 


0,062  5 
0,0676 
0,072g 
0,0784 
0,084 1 

0,0900 
0,0961 
0,1024 
0,1089 
0,1 156 

0,1335 
o,  1 396 
o,  1 369 
0,1 444 

0,l52I 

0,1600 
o,  1 68 1 
0,1764 
o,  1 84g 
o,ig36 

0,2025 
0,2  5oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
0,6400 
0,7225 
0,8100 
o,go25 
T  ,0000 


■   Ir  -\-  r-')- 


+ 


nearly. 


591 

592 

593 

594 

5g 

59 

59 

59 

ti8 

118 

119 

"9 

177 

178 

178 

178 

2  36 

237 

237 

238 

2q6 

296 

297 

297 

355 

355 

356 

356 

4i4 

4i4 

4i5 

4i6 

473 

474 

474 

475 

533 

533 

534 

535 

595 
60 

"9 
179 
238 

298 
357 
417 
476 
536 


596 


60 
119 
179 
238 

298 
358 
4'7 
477 
536 


597 


60 

"9 

179 
239 

299 
358 
418 
478 
537 


598 


60 
120 

179 
239 

299 
359 
419 
478 
538 


399 

60 
120 

180 
240 
3oo 
35g 
4'9 
479 
539 


TABLE  II.- 

-  To  tmJ  the  time  T; 

lie  suir 

of  the  latl 

i  r-f-r",  am!  the 

chord  e  heiiif;  given 

Sum  of  Iho  Ka'lil  r-j-r". 

Prop,  parts  Ibl'  tlio  aolii  uf  tlif  Itudii.     1 
ll2iSI/il5l6i-,l8lol 

Chord 
C. 

0,00 

4,25 

4,26 

4,27 

4,28 

4,29 

4,30 

2 

3 

0     0 
0     0 
0     1 

0  0 

1  I 
I     I 

I 
I 
2 

I 
2 

I     I 

? 

I 
2 
3 

Days  Idif. 

Dii>3  |Jif. 

Days  Idir. 

Days  |dir 

Dnys  Idif. 

l)uy3  Idif. 

I 
2 

2 

3 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,OUtiO 

0,01 

0,599 

I 

0,600 

I 

0,601 

0 

0,601 

I 

0,602 

1 

o,(io3 

0 

O.CtOOI 

4 

0     1 

I      2 

2 

2 

3 

3 

4 

0,02 

1,198 

2 

1,200 

1 

1,201 

2 

1,20J 

1 

1,204 

1 

l,205 

2 

0,0004 

o,o3 

iryS 

2 

1,800 

2 

1 ,802 

2 

1,804 

2 

I,8o() 

2 

1,808 

2 

0,0009 

5 

I      1 

2     2 

3 

3 

4 

4 

5 

o,o4 

2,397 

3 

2,4oo 

2 

2,402 

3 

2,4o5 

3 

2,408 

3 

2,4lJ 

3 

0,0016 

6 

7 

I      1 

2     2 
2     3 

3 
4 

4 
4 

4 
5 

5 
6 

5 
6 

o,o5 

2.qq6 

4 

3,000 

3 

3.003 

4 

3,007 

3 

3,010 

4 

3,oi4 

3 

0,0025 

8 

I     2 

2     3 

4 

5 

6 

C 

7 

0,06 

3.5^ 

4 

3,599 

5 

3,604 

4 

3,608 

4 

3,612 

4 

3,616 

5 

o,oo36 

9 

I     2 

3    4 

5 

5 

6 

7 

8 

0,07 

4,>94 

5 

4,199 

5 

4,204 

5 

4,209 

5 

4,3 14 

5 

4,219 

5 

0,0049 

3    4 

3  4 

4  5 

5 

6 

8 

0,08 

4.794 

5 

4,-99 

6 

4,8o5 

6 

4.811 

t 

4,816 

6 

4,822 

5 

0,0064 

10 

I     2 

7 

9 

0,09 

5,393 

6 

5,399 

7 

5,406 

6 

5,412 

b 

5,418 

6 

5,424 

7 

0,0081 

1  1 
1 3 

I     3 
I      2 

6 
6 

7 
7 

8 
8 

i(- 

10 
1 1 

0,10 

5.Q92 

_ 

5.999 

-. 

6,006 

^ 

6,01 3 

7 

6,020 

7 

6,027 

7 

0,0100 

i3 

1     3 
I     3 

4     5 

7 

8 
& 

9 

u 

1 2 
i3 

0,1  I 

6,591 

8 

6,599 

8 

6,607 

7 

6,6 1 4 

b 

6,622 

8 

6,63o 

8 

0,01 2 1 

.4 

4    6 

7 

10 

1 1 

0,12 

7,190 

9 

7.199 

8 

7.207 

9 

7,216 

b 

7,224 

9 

7,233 

8 

0,01 44 

i5 

2     3 

5    6 

8 

9 
10 

1  1 

12 

.4 

0,1 3 

7,-8q 

10 

7.-99 

9 

7,808 

9 

7,817 

9 

7,826 

9 

7,835 

9 

0,0169 

16 

3     3 

5    6 

h 

1 1 

iC 

.4 

o,i4 

8,389 

9 

8,398 

10 

8,4o8 

10 

8,418 

i< 

8,428 

10 

8,438 

10 

0,0196 

17 

2     3 

5     7 

g 

to 

12 

U 

i5 

0,1 5 

8,988 

10 

8,998 

II 

9,009 

10 

9,019 

II 

g,o3o 

IC 

9.040 

II 

0,0225 

18 
19 

2    4 
2    4 

5  7 

6  8 

9 
10 

1 1 
1 1 

i3 
i3 

14 
it 

16 

17 

0,16 

9,58- 

11 

9.598 

1 1 

9,609 

12 

9,621 

1 1 

9,632 

11 

9,643 

11 

0,02  56 

0,17 

10,186 

12 

10,198 

12 

10,210 

12 

10,222 

12 

10,234 

12 

10,246 

12 

o,<;)28g 

20 

2    4 

6    8 

10 

1 3 

14 

it 

18 

0,18 

io,-85 

i3 

10,798 

12 

10,810 

i3 

10,823 

i3 

io,836 

12 

10,848 

i3 

o,o324 

21 

2    4 

6    8 

1 1 

i3 

i5 

f 

.9 

0,19 

11,384 

i4 

11,398 

i3 

ii,4ii 

i3 

11,424 

14 

11,438 

i3 

ii,45i 

i3 

o,o36i 

22 

23 

2    4 

2     5 

7     9 

7     g 

1 1 
12 

.3 
i4 

i5 
iG 

I^ 
I^ 

20 
21 

0,20 

11,983 

i4 

".997 

.4 

12,011 

14 

12,025 

.4 

12,039 

i4 

i2,o53 

i5 

o,o4oo 

24 

2     5 

7  10 

I  2 

i4 

'7 

IÇ 

22 

0,21 

12,582 

i5 

12,597 

i5 

12,612 

i5 

12,637 

14 

12,641 

i5 

12,656 

i5 

0,044 1 

0,22 

i3,i8i 

16 

13,197 

i5 

l3,212 

16 

l3,228 

i5 

13.243 

16 

i3,25g 

i5 

0,0484 

25 

3     5 

8  10 

i3 

.5 

18 

21 

23 

0,23 

13,780 

16 

13,796 

'7 

i3.8i3 

16 

13,829 

16 

i3,845 

16 

1 3,861 

16 

o,o52g 

26 

3     5 

8  10 

i3 

16 

lb 

2 

23 

0,24 

14,379 

17 

14,396 

17 

i4,4i3 

17 

.4,430 

17 

14,447 

17 

14,464 

16 

0,0576 

27 
28 

3     5 
3     6 

8  II 
8  II 

i4 
i4 

16 

17 

19 

2Û 

2: 

25 

24 

25 

0,25 

14,978 

18 

14,996 

17 

i5,oi3 

18 

i5,o3i 

ife 

.5,049 

17 

1 5,066 

18 

0,0625 

29 

3     6 

9  '2 

i5 

17 

20 

2; 

26 

0,26 

.5,577 

18 

15,595 

19 

i5,6i4 

18 

1 5,632 

ifc 

1 5,650 

19 

1 5,66g 

18 

0,0676 

0,27 

16,176 

'9 

16,195 

'9 

16,214 

'9 

16,233 

19 

16,252 

19 

16,271 

19 

0,0729 

3o 

3    6 

9  12 

i5 

18 

21 

24 

27 

0,28 

.6,775 

20 

16.-95 

19 

16,814 

20 

i6,834 

2( 

i6,854 

'9 

.6,873 

20 

0,0784 

3i 

3    6 

9  " 

16 

19 

22 

25 

28 

0,2g 

17.374 

20 

17,394 

21 

17.4.5 

20 

.7,435 

2( 

17,455 

21 

17,476 

20 

0,084 1 

32 

33 

3    6  , 
3     7  I 

0  i3 
0  i3 

16 

17 

'9 
20 

23 
23 

2f, 
2t 

29 
3o 

o,3o 

17>973 

21 

17,994 

21 

i8,oi5 

21 

i8,o36 

21 

18,057 

21 

18,078 

21 

o,ogoo 

34 

3     7  I 

0  .4 

17 

20 

34 

27 

3i 

0,3 1 

18,572 

21 

.8,593 

32 

i8,6i5 

22 

1 8,637 

22 

18,659 

22 

i8,6Si 

21 

o,og6i 

35 

28 

32 
32 

33 
34 

0,32 

19.170 

23 

19,193 

22 

ig,2i5 

33 

19,238 

22 

19,360 

23 

ig,283 

22 

0,1024 

35 

4     7  I 

1  i4 

18 

21 

0,33 
0,34 

20,368 

23 

34 

19.79' 
2o,3g2 

24 
24 

19,816 
20,4.6 

23 

24 

ig,83g 
20,440 

23 
34 

19^862 
20,464 

23 
33 

ig,885 
20,487 

?3 
24 

0,1  o8g 
0,1 1 56 

36 

37 
38 

4     7  1 
4    7  I 
4     8  I 

1  .4 
1  .5 
1  .5 

18 
'9 
.9 

22 
22 

23 

25 

26 

27 

3^ 
3c 

0,35 

20,967 

24 

20,991 

25 

21,016 

25 

2i,o4i 

24 

3 1  ,o65 

25 

2 1 ,090 

24 

0,1225 

39 

4    8  I 

2  16 

20 

23 

27 

3i 

35 

0,36 

2  1,565 

26 

2i,5gi 

25 

21,616 

25 

2 1 ,64 1 

26 

3 1 ,667 

25 

21,69? 

25 

0,1 2g6 

4., 
4. 
42 
43 

4    8  I 
4     8  I 
4    8  I 
4    9  I 

2  16 

2  16 

3  .7 
3  17 

24 

25 
25 

26 

28 
29 

3p 

36 

37 
38 

0,37 
o,38 

22,164 
22,763 

26 
26 

22,igo 
22,789 

26 

27 

22,216 
22,816 

26 

27 

22,242 
22,843 

26 

27 

22,268 
22,870 

26 
26 

22,2g4 
22,8g6 

26 

27 

0,1 3(39 
0,1 444 

30 
21 

33 
34 
34 

0,39 

23,36i 

28 

23,389 

27 

23,4i6 

28 

23,444 

27 

23,47. 

27 

23,4g8 

28 

0,1 52  I 

21 

23 

=9 
3o 

39 

o,4o 

23,960 

28 

23,988 

28 

24,016 

28 

24,044 

28 

24,072 

28 

24,.  00 

28 

0, 1 600 

44 

4    g  I 

3  .8 

22 

26 

3i 

35 

40 

0,4 1 

24,558 

=9 

24,587 

29 

24,616 

29 

24,645 

29 

24,674 

29 

24.703 

28 

0,1681 

45 
46 
47 
48 

5       r,    T 

418 
4  i& 
4  '9 
4  '9 

23 

27 

33 

36 

4i 

0,42 

25,i57 

29 

25,186 

3o 

25,216 

3o 

25,246 

29 

25,275 

3o 

25,3o5 

29 

0,1764 

5    a 

23 

28 

32 

37 

4i 

0,43 

25,755 

3. 

25,786 

3o 

25,816 

3o 

25,846 

3o 

25,876 

3i 

25,go7 

3o 

0,1849 

5     g  I 

24 
24 

28 

33 

38 

42 

0,44 

26,354 

3i 

26,385 

3i 

26,416 

3. 

26,447 

3i 

26,478 

3o 

26,508 

3i 

o,ig36 

J     g  I 

5  10  I 

29 

34 

38 

43 

0,45 

26,952 

32 

26,984 

3i 

27,01 5 

32 

27,047 

33 

27,07g 

3i 

27,110 

32 

0,2025 

49 

5  10  I 

5  20 

25 

29 

34 

39 

44 

o,5o 

29,943 

36 

59.979 

35 

3o,oi4 

35 

3o,o49 

35 

3o,o84 

35 

3o,  1 1 9 

36 

o,35oo 

5o 

5  10  I 

5  20 

25 

3o 

35 

40 

45 

0,55 

32,934 

39 

32,g73 

38 

33,011 

39 

33,o5o 

39 

33,089 

38 

33,127 

39 

o,3o2  5 

5i 

5  10  I 

5  20 

26 

3i 

36 

4. 

46 

0,60 

35,923 

42 

35,g65 

43 

36,oo8 

42 

36,o5o 

42 

36,og2 

42 

36, 1 34 

42 

o,36oo 

52 

5  10  I 

6  21 

26 

3i 

36 

42 

47 

0,65 

38.911 

46 

38,g57 

46 

39,003 

45 

39,048 

46 

3g,og4 

46 

3g,i4o 

46 

0,4225 

53 

5  II  1 

6  21 

27 

32 

37 

42 

48 

o,7<j 

41,897 

5o 

4., 947 

49 

4i,gg6 

5o 

42,046 

49 

42,og5 

49 

42,144 

49 

o,4goo 

54 

5  II  I 

6  22 

27 

32 

38 

43 

49 

0,75 

44,882 

54 

44,936 

52 

44,988 

53 

45,o4i 

53 

45,og4 

53 

45,147 

53 

o,5625 

55 

5  II  I 

7  22 

28 

33 

39 

44 

5o 

0,80 

47.866 

57 

47,923 

56 

47.979 

57 

48,o36 

56 

48,092 

56 

48,i48 

57 

0,6400 

56 

5  II  I 

7  22 

28 

34 

39 

45 

5o 

o,85 

5o,848 

60 

50,908 

60 

50,968 

60 

5 1, 028 

60 

5 1, 088 

60 

5i,i48 

60 

0,7225 

57 

5  I  I   I 

7  23 

29 

34 

4o 

46 

5i 

0,90 

53,8p8 

63 

53,891 

64 

53,955 

64 

54,019 

63 

54,082 

64 

54,146 

63 

0,8 1 00 

58 

5  12  I 

723 

29 

35 

4. 

46 

52 

0,95 

56,8o6 

67 

56,873 

67 

56,940 

68 

57,008 

67 

57,075 

67 

57,142 

67 

o,go2  5 

59 

i  12  I 

8  24 

3o 

35 

4. 

47 

53 

1,00 

59,782 

7. 

59,853 

71 

59,924 

70 

59,994 

7. 

6o,o65 

71 

60, 1 36 

70 

1 ,0000 

60 
61 
62 
63 
64 

5  12  I 
5  12  I 
5  12  I 
5  i3  1 
3  i3  I 

8  24 
S  24 

9  25 

?,    25 

3o 
3i 
3 1 

32 

36 

42 
43 
43 
44 

48 

t 
5o 

54 
55 
56 

57 
58 

9,0313  1 

9,0738 

9,1165" 

9,1592 

9,2021 

9,2450  1 

"?~ 

37 
37 
38 

^   .  (r  -|-  I- ") '^    or    r"^  -{-  r'"^    nejirty.                                                      | 

598 

599 

600 

601 

602 

6o3 

9    23 
9    26 

32 

38 

45 

5. 

I 

60 

60 

60 

60 

60 

60 

I 

65 
66 

7   i3  2 
7  i3  2 

0  26 
a  26 

33 
33 

39 
40 

46 
46 

52 

53 

59 

2 

3 

120 
■79 

120 
180 

120 
180 

120 
180 

120 
181 

121 

181 

2 
3 

67 
68 

7  i3  2 
^  i4  2 

T    27 
D    27 

34 
34 

4o 
4i 

47 
48 

54 
54 

60 
61 

4 
5 

239 

240 

3oo 

240 

3oo 

340 

3oi 

241 

3oi 

241 
302 

4 
5 

69 

7  i4  2 

I     28 

35 

4i 

48 

55 

62 

6 

359 

36o 

36 1 

36i 

362 

6 

70 

7  i4  2 

I     28 

35 

42 

49 

56 

63 

7 

419 

4.9 

420 

421 

421 

422 

7 

80     f 

i  16  2 

^    32 

40 

48 

56 

64 

72 

8 

4-'8 

479 

480 

48 1 

482 

482 

8 

90    ( 

)  18  2 

-  36 

45 

54 

63 

2' 

81 

9 

538 

539 

540 

54 1 

542 

543 

9 

00  11 

20  3 

4o 

5< 

6o| 

70  eoi9o| 

il6 


rABLE 

II 

—  To  find  the  time  T 

,  the  sum  of  the 

radii 

r  +  r", 

and 

the  chord 

e  being  given. 

SumoftheKadii  r+i-". 

Chord 
C. 

4,31 

Days  |dir. 

4,32 

4,33 

4,34 

4,35 

4,36 

4,37 

4,38 

Days|ilif. 

4^39 

4,40 

Days  Idif. 

Days  Idif. 

Days  Idif. 

Days  Idif. 

Days|dif. 

Days  Idif. 

Days  |dif. 

Days  |dif. 

0,00 

0,000 

0,00c 

0,000 

0,000 

0,000 

0,00c 

o,ooo| 

0,000 

0,00c 

0,000 

0,0000 

0,01 

o,6o3 

1 

0,60^ 

I 

0,60  5 

I 

0,606 

0 

0,606 

I 

0,607 

I 

o,6of 

0 

0,608       1 

o,6oc 

I 

0,610 

0 

0,000 1 

0.02 

1 ,207 

1 

1,208 

3 

1,310 

I 

1,311 

I 

1,212 

3 

1,31^ 

I 

I,2l5|      2 

1,217       1 

I,3lt 

I 

l,2lg 

2 

0,0004 

o,o3 

1,810 

2 

1,812 

3 

i,8i4 

3 

1,817 

2 

1.81& 

2 

1,821 

3 

1,82- 

2 

1,82 

)     2 

1,83- 

2 

1,829 
2,439 

2 

0,000c 
0,0016 

o,o4 

2,4i4 

2 

2,416 

3 

3,4ig 

3 

2,422 

3 

3,435 

3 

2,428 

3 

2,43o      3 

2,433     3 

2,43e 

3 

3 

o,o5 

3,017 

4 

3,021 

3 

3,024 

4 

3,028 

3 

3,o3i 

4 

3,o35 

3 

3,o3f 

4 

3,04 

3 

3,045 

3 

3,o48 

4 

0,0025 

0,06 

3,621 

4 

3,625 

4 

3,629 

4 

3,633 

4 

3,637 

4 

3,64i 

5 

3,64e 

4 

3,65o     4 

3,654 

4 

3,658 

4 

o,oo36 

0,07 

4,224 

5 

4,229 

5 

4,334 

5 

4,339 

5 

4,M4 

4 

4,248 

5 

4,25: 

5 

4,258     5 

4,263 

5 

4,268 

5 

0,0049 
0,0064 

0,08 

4,827 

6 

4,833 

6 

4,83q 

5 

4.844 

6 

4.85o 

5 

4,855 

6 

4,861 

5 

4,866     6 

4,872 

6 

4,878 

5 

o,og 

5,43 1 

6 

5,437 

6 

5,443 

7 

5,45o 

6 

5,456 

6 

5,463 

6 

5,46£ 

7 

5,47; 

6 

5,481 

6 

5,487 

6 

0,008 1 

0,10 

6,o34 

7 

6,o4i 

7 

6,o48 

7 

6,o55 

7 

6,062 

7 

6,069 

7 

6,07e 

7 

6,08; 

7 

6,ogo 

7 

6,097 

7 

0,0100 

0,11 

6,638 

7 

6,645 

8 

6,653 

8 

6,661 

7 

6,668 

8 

6,676 

8 

6,684 

7 

6,691 

8 

6,6gg 

7 

6,706 

8 

0,01 2 1 

0,12 

7.241 

8 

7,24q 

9 

7,358 

8 

7,366 

8 

7,274 

9 

7.283 

8 

7.291 

8 

7,29c 

9 

7,3o8 

8 

7,3i6 

8 

0,01 44 

o,i3 

7,844 

9 

7,853 

9 

7,862 

10 

7.873 

9 

7.881 

9 

7.890 

9 

7.89c 

9 

7,90s 

9 

7,gi7 

9 

7,g26 

g 

0,01 6g 

0,14 

8,448 

9 

8,457 

10 

8,467 

10 

8,477 

10 

8,487 

g 

8,496 

10 

8,5oè 

10 

8,5  r( 

10 

8,526 

9 

8,535 

!0 

0,0196 

o,i5 

9,o5i 

10 

9,061 

II 

9.072 

10 

g,o82 

II 

9,093 

10 

g,io3 

II 

9,114 

10 

Q,I2^ 

II 

g,i35 

10 

9,145 

.  10 

0,0225 

0,16 

9.654 

13 

9,666 

11 

9.677 

II 

9,688 

II 

9.699 

II 

9,710 

II 

9.721 

II 

9.73. 

13 

9,744 

II 

9.755 

II 

0,02  56 

0,17 

10, 258 

12 

10,270 

" 

10,281 

12 

10,293 

12 

!o,3o5 

12 

io,3i7 

12 

10,33g 

12 

10,341 

II 

10,352 

12 

io,364 

13 

0,028g 

0,18 

10,861 

i3 

10,874 

13 

10,886 

i3 

10,89g 

12 

io,gii 

i3 

io,g34 

13 

10,936 

i3 

io,94c 

12 

io,g6i 

i3 

10,974 

13 

o,o324 

0,19 

1 1 ,464 

i4 

11,478 

1 3 

11,491 

i3 

ii,5o4 

i3 

ii,5i7 

i4 

ii,53i 

i3 

11,544 

i3 

11,55: 

i3 

11,570 

i3 

11,583 

i3 

o,o36i 

0,20 

12,068 

i4 

12,083 

i3 

13,095 

i4 

1 3 , 1  og 

i4 

12,123 

14 

I3,i37 

i4 

I3,l5l 

i4 

I3,i65 

i4 

12,17g 

i4 

13,193 

i4 

o,o4oo 

0,21 

12,671 

i4 

13,685 

i5 

13,700 

i5 

I2,7i5 

i4 

12,73g 

i5 

13,744 

i5 

13,759 

i4 

12,773 

i5 

12,788 

i4 

13,802 

i5 

o,o44i 

0,22 

•3,274 

i5 

13,289 

16 

i3,3o5 

i5 

1 3,320 

i5 

1 3,335 

16 

i3,35i 

i5 

1 3,366 

i5 

i3,38i 

16 

13,397 

i5 

i3,4i2 

i5 

o,o484 

0,23 

13,877 

16 

13,893 

16 

13,909 

16 

1 3,935 

17 

i3,g43 

16 

i3,g58 

16 

1 3,974 

16 

i3.gqr 

16 

14,006 

i5 

I4.03I 

r6 

0,0529 

0,24 

i4,48o 

17 

14,497 

17 

i4,5i4 

17 

i4,53i 

17 

14,548 

16 

i4,564 

17 

i4,58i 

17 

14,598 

16 

i4,6i4 

17 

i4,63i 

17 

0,0576 

0,25 

1 5,084 

17 

i5,ioi 

18 

i5,iig 

17 

i5,i36 

17 

i5,i53 

18 

15,171 

17 

i5,i88 

18 

i5,3o6 

'7 

I  5,223 

17 

1 5,240 

18 

0,0625 

0,26 

15,687 

18 

i5,7o5 

18 

15,733 

18 

1 5,74 1 

18 

■5,759 

'9 

15,778 

18 

15,796 

18 

i5,8i4 

18 

1 5,832 

18 

i5,85o 

18 

0,0676 

0,27 

16,290 

19 

16,309 

19 

16,338 

19 

16,347 

18 

i6,365 

'9 

1 6,384 

19 

1 6,4^3 

19 

16,422 

'9 

16,44 1 

18 

16,459 

19 

0,0729 

0,28 

16,893 

20 

16,913 

19 

i6,q32 

30 

i6,q53 

■9 

16,971 

20 

16,991 

19 

17,010 

20 

i7,o3o 

ly 

17,049 

20 

17,069 

19 

0,0784 

0,29 

17,496 

20 

I7,5i6 

21 

17,537 

30 

17.557 

20 

17,577 

20 

17,597 

31 

17,618 

20 

17,638 

20 

17,658 

20 

17,678 

20 

o,o84i 

o,3o 

18,09g 

21 

l8,130 

21 

i8,i4i 

31 

18,163 

21 

i8,i83 

21 

18,204 

21 

l8,325 

21 

18,246 

31 

18,267 

20 

18,287 

31 

0,0900 

0,3 1 

18,702 

22 

18,734 

22 

18,746 

31 

18,767 

22 

18,789 

22 

18,811 

21 

i8,833 

22 

18,8  54 

21 

18,875 

22 

18,897 

21 

0,0961 

0,32 

i9,3o5 

23 

19,338 

22 

19,350 

32 

19.372 

23 

19,395 

33 

19,417 

22 

19,439 

33 

19,463 

22 

19,484 

22 

ig,5o6 

22 

0,1024 

0,33 

19,908 

23 

ig,93i 

23 

19,954 

24 

19,978 

23 

20,001 

23 

20,024 

23 

20,047 

22 

2o,o6g 

23 

30,og3 

23 

20,Il5 

23 

0,1089 

0,34 

20,5 11 

24 

20,535 

24 

2o,55g 

24 

3o,583 

23 

20,606 

24 

2o,63o 

24 

20,654 

23 

20,677 

24 

30,701 

24 

20,735 

23 

0,1 1 56 

0,35 

2I,Il4 

25 

3i,i3g 

24 

2i,i63 

25 

21,188 

24 

21,312 

34 

31,236 

25 

21,261 

24 

21,285 

34 

3 1 ,309 

25 

3  1,334 

24 

0,1335 

o,36 

21,717 

25 

31,742 

26 

21,768 

25 

21.793 

25 

21,818 

35 

21,843 

25 

21,868 

25 

2i,8g3 

25 

3 1 ,9 1 8 

25 

31,943 

25 

0,1 296 

0,37 

22,320 

26 

3  2,346 

36 

23,373 

36 

22,398 

25 

22,433 

26 

2  3,44q 

26 

33,475 

26 

22,5oi 

25 

22,526 

26 

22,552 

2t3 

0,1 369 

o,38 

22,923 

27 

32,950 

26 

22,976 

2T 

33,oo3 

26 

33,029 

37 

3  3,o56 

36 

23,083 

27 

23,  log 

26 

23,i35 

26 

23,161 

27 

0,1 444 

0,39 

23,526 

27 

23,553 

27 

23,58o 

28 

33,608 

27 

23,635 

27 

33,663 

27 

33,689 

27 

23,716 

27 

23,743 

27 

23,770 

27 

0,1 53  I 

o,4o 

24.128 

=9 

24,157 

27 

24,184 

28 

34,212 

28 

24,240 

38 

24,368 

38 

34,396 

28 

24,324 

38 

34,352 

27 

24,379 

28 

0,1600 

o,4i 

24,73i 

29 

24,760 

29 

24,789 

28 

34.817 

29 

24,846 

?9 

24.875 

28 

34,go3 

29 

24,932 

28 

24,960 

29 

24.989 

2« 

0,1681 

0,42 

25,334 

29 

25,363 

3o 

25,393 

29 

35,422 

29 

35,45i 

3o 

35,481 

29 

35,5io 

29 

25,539 

29 

2  5,568 

3o 

25,5g8 

29 

0,1764 

0,43 

25,937 

3o 

25,967 

3û 

25,997 

3o 

26,027 

3o 

36,057 

3o 

26,087 

3o 

36,117 

3o 

26,147 

3o 

26,177 

3o 

36,207 

29 

0,1849 

0,44 

26,539 

3i 

26,570 

3i 

26,601 

3i 

26,633 

3o 

36,663 

3i 

26,693 

3i 

26,724 

3o 

26,754 

3i 

26,785 

3o 

26,815 

3\ 

0,1936 

0,45 

27,142 

3i 

37,173 

32 

27,205 

3i 

27,236 

32 

37,368 

3i 

27,299 

32 

37,331 

3i 

27,362 

3i 

27,393 

3i 

27,424 

32 

0,2025 

o,5o 

3o,i55 

35 

30,190 

35 

3o,225 

35 

30,260 

34 

30,294 

35 

3o,339 

35 

3o,364 

35 

3o,3q9 

35 

30,434 

34 

3o,468 

35 

o,25oo 

0,55 

33,166 

39 

33,3o5 

38 

33,243 

39 

33,282 

38 

33,3io 

38 

33,358 

39 

33,3g7 

38 

33,435 

38 

33,473 

38 

33,5ii 

39 

o,3o35 

0,60 

36,176 

43 

36,319 

43 

36,261 

42 

36,3o3 

4i 

36,344 

42 

36,386 

42 

36,438 

42 

36,470 

42 

36,5 12 

4i 

36,553 

42 

o,36oo 

o,65 

39,186 

45 

39,231 

46 

39.277 

45 

39,322 

46 

3g,368 

45 

39,41 3 

45 

39,458 

46 

39,504 

45 

39,54g 

45 

39,594 

45 

0,4225 

0,70 

42,193 

5o 

42,343 

49 

42,292 

49 

42,341 

49 

42,390 

49 

42,439 

48 

43,487 

49 

42,536 

49 

42,585 

49 

42,634 

48 

o,4goo 

0,75 

45,200 

52 

45,353 

53 

45,3o5 

53 

45,358 

52 

45,4io 

53 

45,463 

53 

45,5i5 

53 

45,567 

52 

45,619 

53 

45,672 

53 

o,5625 

0,80 

48,2o5 

56 

48,261 

56 

48,317 

56 

48,373 

56 

48,42Q 

56 

48,485 

56 

48,541 

56 

48,597 

56 

48.653 

55 

48,708 

56 

o,64oo 

o,85 

5 1,208 

60 

51,268 

5g 

5i,337 

60 

51,387 

59 

5 1, 446 

60 

5i,5o6 

59 

5 1, 565 

60 

51,625 

59 

5 1, 684 

59 

5 1, 743 

59 

0,7335 

0,90 

54,209 

63 

54,273 

64 

54,336 

63 

54,3gg 

63 

54,462 

63 

54,525 

63 

54,588 

63 

54,65 1 

63 

54.714 

60. 

54,776 

63 

0,8100 

0,95 

57,209 

67 

57,276 

66 

57.342 

67 

57,4og 

67 

57,476 

66 

57,543 

67 

57,609 

66 

57,675 

67 

57,742 

66 

57,808 

66  o,go25 

1,00 

60,206   71 

60,277 

70 

60,347 

70 

60,4 1 7 

70 

60, 
9; 

487I 

71 

6o,558 

70 

60,638    70 

6o,6g8 

69 

60,767 

70 

60,837 

70  1,0000 

9,2881 

9,33121 

9,3745  1 

9,41781 

4613  1 

9,5048  1 

9,5485 

9,5922 1 

9,6361  1 

9,6800 1    c2    1 

k-tr^T")"     or    r^  -|-  r"=    nearly.                                                                                                               | 

602 

6o3 

604 

6o5 

606 

607 

608 

609 

610 

I 

60 

60 

60 

61 

61 

61 

61 

61 

61 

I 

2 

120 

121 

lai 

121 

121 

121 

132 

122 

122 

3 

3 

181 

181 

181 

182 

182 

182 

183 

i83 

i83 

3 

4 

241 

241 

242 

342 

342 

243 

243 

244 

244 

4 

5 

3oi 

3o2 

3o2 

3o3 

3o3 

3o4 

3o4 

3o5 

3o5 

5 

6 

36 1 

362 

362 

363 

364 

364 

365 

365 

366 

6 

7 

421 

422 

433 

434 

434 

435 

436 

426 

427 

7 

8 

482 

482 

483 

484 

485 

486 

486 

487 

488 

8 

9 

5 

42 

543 

544 

5 

45 

545 

546  1 

547  1 

548  1 

549 

1 

9 

TV  BLE   II.  —  To  fiml  the  time  T\  the  sum  of  the  r;i(lii  ?-(-)•  ",  anil  the  chord  <•  hehig  t^ivcn. 


tfum  ol    t  ho  Rati  II   r -f- r  ".                                                                     | 

Chord 
C. 

4,41 

4,42 

4,43 

4,44 

4,45 

4,46 

Days  |dif. 

Days  |dir. 

Days  Idif. 

Days  |dil'. 

Days  |dil". 

Days  |dif. 

0,00 
o,ui 
o,o:i 
o,u3 
o,u4 

0,000 
0,610 
1,23  1 
1,83 1 
2,442 

1 

1 
2 

2 

0,000 
0,611 
1,222 

1,833 
2  AAA 

1 
2 
3 
3 

0,000 
0,612 
1,234 

1,835 
2,447 

0 
1 
3 

3 

0,000 
0,612 
1,235 
1,837 

2,45o 

I 
I 
3 
3 

0,000 
0,61 3 
1,226 
1,83() 
2,453 

I 
3 

3 
3 

0,000 
0,6l4 
1,328 
1,843 

2,455 

1 
I 
2 

3 

0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

o,o5 
0,06 
0,07 
o,ufci 
0,uy 

3,o52 
3,(562 
4,273 
4.883 
5,493 

3 
4 
5 
6 

3,o55 
3,666 
4,378 
4,889 
5,5oo 

4 
5 
4 
5 
6 

3,o5q 
3,671 
4,282 
4,894 
5,5o6 

3 
4 
5 
6 
6 

3,062 

3,675 
4.387 

4,900 
5,5i2 

4 
4 
5 
5 
6 

3,066 
3,679 
4.392 
4,905 

5,5i8 

3 
4 
5 
6 
6 

3,069 

3,683 
4,397 
4,911 
5,524 

4 

4 
5 

7 

0,0025 
o,oo36 
0,0049 
0,0064 
0,008 1 

0,10 
0,1  I 
0,1  :' 
o,i3 
0,14 

6,104 
6,714 
7,334 

8 
9 
9 
10 

6,111 
6.722 
7,333 

7,944 
8,555 

8 
9 
9 

6,118 
6,729 
7.341 
7,953 
8,564 

7 

8 
8 
9 

lO 

6,125 
6.737 
7,349 
7.963 
8,574 

6 

7 

9 
9 
10 

6,i3i 
6,744 
7,358 
7.97' 
8,584 

7 
8 
8 
9 
9 

6,1 38 
6,753 
7.366 
7.980 
8,593 

7 
8 
8 

9 
10 

0,0100 
0,0121 
0,01 44 
0,0169 
0,0196 

o,i5 
0,16 
0,17 
0,18 
o,Iy 

9.- 50 
9,-66 
10,3-6 
10,986 
11,596 

1 1 
11 

13 

i3 

14 

9,i6() 

9>777 
io,388 

■0,999 
1  i,6io 

10 
11 
II 
12 
i3 

9,176 

9,788 

10,399 

11,01 1 

11,623 

1 1 
1 1 

13 

i3 
i3 

9,187 

9.799 
10,41 1 
1 1,034 
1 1 ,636 

10 
1 1 
12 
12 

i3 

9. '97 
9,810 
10,423 
1 1  ,o36 
1 1 ,649 

10 
11 

13 
13 
l3 

9,207 
9.821 
10,435 
1 1 ,048 
1 1 ,662 

.1 
11 
11 
i3 
i3 

0,0225 
o,o256 
0,0289 
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1  .  (r  +  r'  )'     or     ?•= -f  r  "  '      nearly.                                                         | 

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—  To  find  the  Unie  T 

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le  sum  0 

f  th 

3  radii 

r  +  r". 

and  the  chord  < 

being 

çiven. 

Sura  of  llie  lladii  r  -\-  r".                                                                                                            | 

Chord 
C. 

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14,763 

17 

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16 

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21 

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22 

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22 

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3o,95o 

35 

30,985 

34 

31,019 

34 

o,25oo 

0,55 

33,778 

38 

33.816 

37 

33,853 

38 

33.891 

38 

33,929 

38 

33,967 

37 

34,004 

38 

34,042 

37 

34,079 

38 

34,117 

37 

o,3o25 

0,60 

36,844 

4r 

36;885 

4i 

36,026 

42 

36,968 

4i 

37,000 

4i 

37,o5o 

41 

37,091 

4i 

37,i32 

4i 

37,173 

4' 

37,214 

4i 

o,36oo 

o,65 

39,909 

45 

39,954 

45 

39,999 

AA 

4o,o43 

45 

40,088 

AA 

4o,i33 

45 

40,177 

AA 

40,22I 

45 

40,266 

AA 

4o,3io 

AA 

0,4225 

0,70 

42,973 

48 

43,021 

48 

48 

43,117 

48 

43,i65 

48 

43,21 3 

48 

43,361 

48 

43,309 

48 

43,357 

48 

43,4o5 

48 

0,4900 

0,75 

46,o35 

52 

46,087 

52 

46,139 

5i 

46,190 

52 

46,242 

5i 

46,293 

52 

46,345 

5i 

46,396 

5i 

46,447 

52 

46,499 

5i 

0,5625 

0,80 

49,096 

55 

49.i5i 

56 

49,207 

55 

49,362 

55 

49,317 

55 

4g,372 

54 

49,426 

55 

49,481 

55 

49,536 

55 

49,591 

54 

o,64oo 

o,85 

52,i56 

58 

52,214 

59 

52,273 

58 

52,33i 

59 

52,390 

58 

52,448 

59 

53,507 

58 

52,565 

58 

52,623 

58 

53,681 

58 

0,7225 

0,90 

55,2 13 

63 

55,276 

6? 

55,338 

63 

55.400 

62 

55,462 

61 

55,523 

62 

55,585 

62 

55,647 

62 

55,7oq 

61 

55,770 

62 

0,8100 

0,95 

58,269 

66 

58,335 

66 

58,4oi 

65 

58,466 

65 

58,53 1 

66 

58,597 

65 

58,662 

65 

58,727 

65 

58,793 

65 

58,857 

65 

0,9025 

1,00 

61,323 

70 

6i,3g3 

69 

61,462 

69 

6i,53i 

69 

61,600 

68 

61,668 

69 

61,737 

69 

61,806 

68 

61,874 

J9 

61,943 

68 

1 ,0000 

9,9905 

10,0352 

10,0801 

10,1250 

10,1701 

10,2152 

10,2605 

10,3058 

10,3513 

10,3968] 

^  .   (r  -(-  r")^     or      î^  -f  r"^     nearly.                                                                                                 | 

6i3 

6r4 

6i5 

616 

617 

618 

619 

620 

621 

I 

61 

61 

62 

62 

62 

62 

62 

62 

62 

I 

2 

123 

123 

123 

123 

123 

124 

124 

124 

124 

2 

3 

1 84 

184 

i85 

i85 

i85 

i85 

186 

186 

186 

3 

4 

245 

246 

246 

246 

247 

247 

248 

248 

248 

4 

5 

307 

3o7 

3ù8 

3o8 

3og 

309 

3io 

3io 

3ii 

5 

6 

368 

368 

36g 

370 

370 

37. 

371 

372 

373 

6 

7 

429 

43o 

43i 

43 1 

432 

433 

433 

434 

435 

7 

8 

4qo 

491 

4q3 

493 

494 

494 

495 

496 

497 

8 

9 

5 

5^  1 

553 

554 

5 

54 

,55 

556  1 

557  1 

558 

559 

9 

T.VRLE   II.  — To  tinJ  the  time  T;  the  sum  of  (lie  lailii  r-f-c'',  and  the  chord  <•  beinf;  given. 


Sum  ol 

the 

Kn.lii  r+r". 

Clionl 

4,57 

4,58 

4,59 

Days  |Hir. 

4,60 

4,61 

4,62 

Days  l.lil". 

c. 

Days  |dil". 

Days  |.lcl'. 

Days  IJil". 

Days  lilil". 

o,t)o 

0,000 

0,000 

o,ooc 

0,000 

0,000 

0,000 

0,00t)0 

(),()! 

0.(32  1 

1 

0,632 

I 

0,623 

0 

0,623 

1 

0,624 

I 

0,635 

0 

0,0001 

0,(I2 

ii243 

1 

1,344 

1 

1,345 

2 

1,247 

I 

1,248 

2 

l,25o 

I 

o,o<»o4 

o,<>3 

t,8fi4 

2 

1 ,866 

2 

1 ,868 

2 

1,870 

2 

1,872 

3 

1 ,874 

3 

0,0(109 

o,o4 

2,485 

3 

2,488 

3 

2,491 

3 

2,494 

'2 

2,496 

3 

2,499 

3 

0,0016 

o,o5 

3,107 

3 

3,110 

4 

3,..4 

3 

3,117 

3 

3,120 

4 

3,134 

3 

0,0025 

0,06 

3,728 

4 

3,732 

4 

3,736 

4 

3,740 

4 

3,744 

5 

3,749 

4 

o,oo36 

0,07 

4,35o 

4 

4,354 

5 

4,359 

5 

4,364 

4 

4,368 

5 

4,373 

5 

0,0049 

o,oi) 

4,971 

5 

4,976 

() 

4,982 

5 

4,987 

6 

4,993 

5 

4,998 

5 

0,0064 

0,09 

5,592 

6 

5,598 

fa 

5,604 

7 

5,611 

6 

5,617 

6 

5,623 

6 

0,008 1 

0,10 

6.214 

6 

6,230 

- 

6,227 

7 

6,234 

- 

6,241 

6 

6,247 

7 

0,0100 

0,1 1 

6.835 

7 

6,843 

8 

6;85o 

7 

6,857 

8 

6,865 

7 

6,872 

8 

0,0121 

0,I3 

-,456 

8 

7,464 

8 

7,47' 

9 

7,48. 

8 

-,48q 

8 

7,497 

8 

0,01 44 

0,1 3 

8,077 

9 

8,086 

9 

8.095 

9 

8.104 

9 

8,ii3 

9 

8,122 

8 

0,0169 

o,i4 

8,699 

9 

8,708 

10 

8,718 

9 

8:727 

10 

8,737 

9 

8,746 

10 

o,oi<j6 

0,1 5 

9,330 

10 

9,33o 

10 

9,340 

1 1 

9,35i 

10 

9,361 

10 

9,371 

10 

0,0335 

0,16 

9'94i 

II 

9,953 

1 1 

9,963 

11 

9'974 

11 

9«85 

11 

9,996 

10 

o,o256 

0>i7 

io,563 

1 1 

10,574 

12 

io,586 

11 

10,597 

13 

10,609 

11 

10,620 

12 

0,0289 

0,18 

11,184 

12 

1 1,196 

12 

1 1,208 

12 

1 1.220 

1 3 

1 1,333 

13 

11,245 

12 

o,o324 

0,19 

1 1 ,8o5 

i3 

11,818 

1 3 

I!  ,83! 

i3 

1 1 ,844 

i3 

1 1 ,857 

i3 

11,870 

12 

o,o36i 

0,30 

12,426 

i4 

1 3 ,440 

i3 

12,453 

14 

12,467 

14 

13,481 

i3 

12,494 

i4 

o,o4oo 

0,21 

1 3.048 

14 

13.062 

14 

13,076 

14 

13,090 

1 4 

i3,io4 

i5 

13.119 

i4 

o,o44 1 

0,22 

i3;66o 

i5 

1 3,684 

i5 

1 3,699 

14 

i3.-i3 

i5 

13,738 

i5 

i3,743 

i5 

o,o484 

0,23 

14,290 

i5 

i4,3o5 

16 

1 4,32  1 

16 

i4,33- 

i5 

14,353 

16 

1 4,368 

i5 

0,0529 

0,24 

14,911 

16 

14,927 

I- 

i4:944 

ifa 

14,960 

16 

14,9-6 

16 

14,992 

17 

0,0576 

0,25 

i5,532 

I- 

1 5,549 

i~ 

1 5,566 

17 

1 5,583 

17 

1 5,600 

17 

i5,6i7 

17 

0,0625 

0,26 

i6,i53 

18 

16,171 

18 

16,189 

17 

16.306 

18 

16,224 

17 

16,241 

18 

0,0676 

0,27 

16,774 

19 

16,793 

18 

16,811 

lb 

16,820 

19 

1 6.848 

18 

16,866 

18 

0,0739 

0,28 

i-,395 

20 

17.41 5 

19 

17,434 

19 

17,453 

18 

17,471 

19 

17,490 

'9 

0,0784 

0,29 

18,017 

'9 

i8,o36 

20 

1 8,0  56 

20 

18,076 

19 

18,095 

30 

i8,ii5 

20 

0,084 1 

o,3o 

1 8,638 

20 

1 8,658 

20 

18,678 

21 

18,699 

30 

18,719 

20 

18,739 

21 

0,0900 

0,3 1 

19,259 

21 

19,280 

21 

19,301 

21 

19,333 

31 

19,343 

31 

19,364 

21 

0,0961 

0,32 

19,880 

21 

19.901 

22 

19,923 

33 

19.945 

21 

19.966 

23 

19,988 

22 

0,1034 

0,33 

2o,5oi 

23 

30,523 

22 

20,545 

23 

2o,568 

32 

2o,5go 

22 

20,612 

23 

0,1089 

0,34 

21,121 

24 

2i,i45 

33 

21,168 

23 

21,191 

23 

2(,2l4 

23 

21,237 

23 

0,1 156 

0,35 

2  1,742 

34 

21,766 

24 

2 1 ,790 

24 

3i,8i4 

23 

21,837 

24 

31,861 

24 

0,1225 

o,36 

22.363 

35 

22,388 

34 

22,412 

25 

33,437 

24 

22,461 

34 

3  3,485 

25 

0,1296 

0,37 

22.984 

35 

23,009 

35 

23.034 

26 

23:060 

25 

23,o85 

25 

33,1 10 

25 

0, 1 36g 

o,38 

2  3,6o5 

36 

33,63'i 

36 

23,657 

25 

23,682 

26 

23,708 

36 

33,734 

26 

0,1 444 

0,39 

24,226 

36 

24,252 

37 

24,27g 

26 

24,3o5 

27 

24,332 

36 

34,358 

27 

0,l521 

0,40 

24,847 

37 

34,874 

27 

34,901 

27 

24,938 

27 

24.955 

27 

24,983 

27 

0,1600 

0,4 1 

25,467 

38 

35,495 

38 

35,323 

38 

25,55i 

28 

25,579 

27 

35,606 

38 

0,1681 

0,42 

26,088 

39 

36.1 17 

3fc 

26,145 

59 

26,174 

28 

26,302 

29 

36,33l 

38 

0,1764 

0,43 

36,709 

39 

36.738 

39 

26,767 

29 

36,7g6 

3o 

26,836 

29 

26,855 

29 

0,1849 

0,44 

27,329 

3o 

27,3 5g 

3o 

27,389 

3o 

27,419 

3o 

27,449 

3o 

'7,479 

3o 

o,ig36 

0,45 

27.950 

3i 

37,981 

3o 

28,011 

3i 

28,042 

3o 

38,073 

3i 

28,103 

3o 

0,2025 

o,5o 

3i,o53 

34 

31,087 

34 

3l,I21 

34 

3i.i55 

34 

3i,i8o 

33 

3l,222 

34 

o,25oo 

0,55 

34, 1 54 

38 

34,193 

3- 

34,339 

38 

34,267 

37 

34,3o4 

37 

34,341 

37 

o,3o25 

0,60 

37,255 

4i 

37,396 

4i 

57.33- 

4o 

37,377 

4 1 

37.41& 

4i 

37,459 

40 

o,36oo 

0,65 

40,354 

45 

4o,3g9 

U 

40,443 

Aâ 

40.48- 

Ai 

40,53 1 

AA 

40,575 

AA 

0,4225 

0,70 

43,453 

47 

43,5oo 

48 

43,548 

48 

43,5g6 

Al 

43,643 

48 

43,691 

Al 

0,4900 

0,75 

46,55o 

5i 

46,601 

5i 

46,652 

5i 

46,703 

5i 

46,754 

5i 

46,8o5 

5i 

o,5625 

0,80 

49,645 

55 

49,700 

54 

49.754 

55 

49,809 

54 

49,863 

55 

49,918 

54 

o,64oo 

o,85 

52,739 

58 

53,-97 

58 

52,855 

58 

52,gi3 

58 

53,971 

58 

53,029 

57 

0,7325 

0,90 

55.832 

61 

55,893 

62 

55,955 

61 

56,oi6 

61 

56,077 

61 

56,1 38 

61 

0,8100 

0,95 

58,923 

65 

58,987 

65 

59,052 

65 

59,117 

65 

59,183 

64 

59,246 

65 

0,9035 

1,00 

62,01 1 

fig 

62,080 

68 

62,148 

6f- 

63,316 

68 

63,384 

68 

63,352 

68 

1 ,0000 

10,4425 

l(),4ç 

82 

10,53 

"4Ï 

10.5>= 

00 

10,62 

61 

10.67 

22 

"?^ 

r'  +  . 


630 

62 
124 
186 
348 

3io 

372 
434 
496 

558 


621 
63 

134 

186 
348 
3ii 
373 
435 
497 
55n 


622 

62 

124 
187 
'49 
3ii 

373 
435 
498 
56o 

a17 


623 

62 
125 
187 
249 

3l2 

374 

436 

498 

56 1 


624 


625 


62 

63 

125 

125 

187 

188 

25o 

25o 

3l2 

3i3 

374 

375 

437 

438 

4qq 

5oo 

503 

563 

1  I  '  3  I  4  I  5  I  (i  I  7  I  8  I  9  1 


I 

0 

2 

0 

3 

0 

4 

0 

5 

6 

-T 

8 

9 

10 

1 1 

12 

i3 

i4 

i5 

2 

16 

2 

17 

2 

18 

2 

19 

2 

30 

2 

31 

2 

32 

3 

23 

2 

24 

2 

35 

3 

36 

3 

27 

3 

28 

3 

29 

3 

3o 

3 

i5  I 

16  19  22 
19 


49 


I 
3 

3 

4 

5 
5 
6 

7 
8 

9 
10 
1 1 
12 
i3 

14 
i4 
i5 
16 

17 


23 
33 

34 

3  5 

26 


38 
29 

3o 
3i 

32 
32 

33 
34 
35 

36 

37 
38 

39 
40 

4i 
4i 
42 
43 
AA 

45 
46 

47 


56 
63 


5o 
5o 
5i 

53 

53 

54 
55 
56 

57 
58 

59 
59 
60 
61 
62 

63 
3 


60 


64 

7281 

80I90 


TABLE  II.  —  To  fi  ml  the  time  T;  the  sum  of  the  radii  )■ -f-r",  and  the  chord  c  being  given. 


Sum  ( 

r  Uie  Rai 

il  r 

+  '■' 

Chord 
C. 

4,63 

Days  |(]ir. 

4,64 

4,65        4,66 

4,67 

4,68 

Daysldif. 

4,69 

4,70 

Daysldif. 

4,71 

4,72 

Days  |(lir. 

Days  |dif. 

Days  |dir. 

Days  |dir. 

Days  |dif. 

Days  |dir. 

Days  Idif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,625 

I 

0,626 

I 

0,637 

0 

0,627 

1 

0,628 

1 

0,629 

0 

0,639 

I 

o,63o 

I 

o,63i 

0 

0,63 1 

I 

0,0001 

0,02 

T,25l 

I 

1,252 

2 

1,2  54 

1 

1,255 

1 

1.256 

2 

1,358 

I 

1,259 

1 

1 ,260 

2 

1 ,362 

1 

1,363 

1 

o,ooo4 

o,n3 

1,876 

■1 

1,878 

2 

i,S8o 

2 

1,882 

2 

1,884 

2 

1,886 

2 

1,888 

2 

i,8go 

2 

1,892 

2 

1 ,894 

2 

0,0009 

0,04 

2,502 

2 

2,5o4 

3 

2,5o7 

3 

2,5lO 

2 

2,5l2 

3 

2,5i5 

3 

a,5i8 

3 

2,521 

2 

2,523 

3 

3,536 

3 

0,0016 

o,o5 

3,127 

3 

3,i3o 

4 

3, 1 34 

3 

3,i37 

4 

3,i4i 

3 

3,144 

3 

3,147 

4 

3,i5i 

3 

3,1 54 

3 

3,i57 

4 

0,0025 

0,06 

3,753 

4 

3,757 

4 

3,761 

4 

3.765 

4 

3,769 

4 

3,773 

4 

3,777 

4 

3,781 

4 

3,785 

4 

3,789 

4 

o,oo36 

0,07 

4,378 

5 

4,383 

4 

4,387 

5 

4,392 

5 

4,397 

5 

4,402 

4 

4,406 

5 

4,4 11 

5 

4,416 

4 

4,430 

5 

0,0049 

0,08 

5,oo3 

6 

5,009 

5 

5,oi4 

6 

5,020 

5 

5,025 

5 

5,o3o 

6 

5,o36 

5 

5,04 1 

5 

5.046 

6 

5,o53 

5 

0,0064 

0,09 

5,629 

6 

5,635 

6 

5,64i 

6 

5,647 

6 

5,653 

6 

5,659 

6 

5,665 

6 

5,671 

6 

5,677 

6 

5,683 

6 

0,0081 

0,10 

6,254 

7 

6,261 

7 

6,268 

6 

6,274 

7 

6,281 

7 

6,288 

7 

6,295 

6 

6,3oi 

7 

6,3o8 

7 

6,3 1 5 

6 

0,0100 

0,11 

6,880 

7 

6.887 

7 

6,894 

8 

6,902 

7 

6,909 

8 

6,917 

7 

6,924 

7 

6.931 

8 

6,939 

7 

6,946 

7 

0,01 3 1 

0,12 

7,5o5 

8 

7,5i3 

8 

7,52, 

8 

7,529 

8 

7,537 

8 

7,545 

8 

7,553 

8 

7,56i 

9 

7,570 

8 

7.578 

8 

0,01 44 

o,i3 

8,i3o 

9 

8,139 

9 

8,i48 

9 

8,i57 

8 

8,i65 

9 

8,174 

9 

8,i83 

9 

8,192 

8 

8,200 

9 

8,209 

9 

0,0169 

o,i4 

8,756 

9 

8,765 

10 

8,775 

9 

8,784 

9 

8,793 

10 

8,8o3 

9 

8,812 

10 

8,822 

9 

8,83 1 

9 

8,840 

10 

0,0196 

o,i5 

9,38i 

10 

9>39! 

10 

9,401 

10 

9,4 11 

10 

9,431 

II 

9,432 

10 

9,442 

10 

9,453 

10 

9,462 

10 

9,472 

10 

0,0225 

0,16 

10,006 

11 

10,017 

i  1 

10,028 

1 1 

10,039 

II 

io,o5o 

10 

10,060 

II 

10,071 

1 1 

10,082 

10 

10,092 

II 

io,io3 

II 

0,0256 

0,17 

io,632 

II 

10,643 

12 

10,655 

1 1 

10,666 

12 

10,678 

II 

10,689 

11 

10,700 

13 

10,713 

1 1 

10,733 

12 

10,735 

11 

0,038g 

0,18 

11,257 

12 

11,269 

12 

11,281 

12 

11,293 

i3 

ii,3o6 

13 

ii,3i8 

13 

ii,33o 

13 

11,342 

12 

11,354 

12 

1 1 ,366 

12 

o,o324 

0,19 

11,882 

i3 

11,895 

l3 

1 1  ,go8 

i3 

11,921 

i3 

11,934 

12 

11,946 

i3 

11,959 

i3 

":972 

i3 

11,985 

12 

",997 

i3 

o,o36i 

0,20 

i2,5o8 

i3 

12,531 

14 

12,535 

i3 

13,548 

i4 

12,562 

l3 

12,575 

i3 

13,588 

14 

I  2 ,602 

i3 

i2,6i5 

i4 

12,629 

i3 

o,o4oo 

0,21 

1 3,1 33 

i4 

i3,i47 

i4 

1 3,161 

i4 

13,175 

i5 

13,190 

i4 

1 3,204 

i4 

i3,3i8 

14 

l3,233 

i4 

i3,246 

14 

13,260 

i4 

0,044 1 

0,32 

1 3,75s 

i5 

1 3,773 

i5 

13,788 

i5 

i3,8o3 

i4 

i3,8.7 

i5 

i3,833 

i5 

1 3,847 

i5 

1 3,863 

i5 

13,877 

14 

13,891 

i5 

o,o4S4 

0,23 

i4,383 

16 

14,399 

i5 

i4,4i4 

16 

i4,43o 

i5 

i4,445 

16 

i4,46i 

i5 

14,476 

16 

14,493 

i5 

i4,5o7 

16 

14,523 

i5 

0,0529 

0,24 

15,009 

16 

i5,025 

16 

i5,o4i 

16 

1 5,057 

16 

1 5,073 

16 

l5,oSg 

17 

i5,io6 

16 

1  5,1  22 

16 

i5,i38 

16 

i5,i54 

16 

0,0576 

0,25 

1 5,634 

17 

1 5,65 1 

17 

1 5,668 

16 

1 5,684 

17 

1 5,701 

17 

15.718 

17 

i5,735 

17 

1 5,752 

16 

15,768 

17 

1 5,785 

17 

0,0625 

0,26 

16,259 

18 

16,277 

T7 

16,294 

18 

1 6,3 1 3 

17 

16,329 

18 

16,347 

17 

1 6,364 

18 

16,382 

17 

16,399 

'7 

i6,4i6 

18 

0,0676 

0,27 

16,884 

18 

16,902 

'9 

16,921 

18 

16.939 

18 

16,957 

18 

16,975 

18 

16.993 

18 

17,01 1 

19 

i7,o3r 

18 

17,048 

18 

0,0739 

0,28 

17,509 

19 

.7,528 

19 

17,547 

19 

17,566 

19 

17,585 

19 

17,604 

19 

17,633 

18 

17,641 

19 

17,660 

19 

17,679 

19 

0,0784 

0,2g 

i8,i35 

19 

i8,i54 

20 

18,174 

'9 

18,193 

20 

i8,2i3 

19 

18,232 

20 

18,353 

19 

18,271 

20 

18,291 

'9 

i8,3io 

19 

o,o84i 

o,3o 

18,760 

20 

18,780 

20 

18,800 

20 

18,820 

21 

18,841 

20 

18,861 

20 

18,881 

20 

i8,goi 

30 

i8,g2i 

30 

18,941 

20 

0,0900 

o,3i 

19,385 

21 

19,406 

21 

19,427 

20 

19,447 

21 

19,468 

21 

19,48g 

21 

■9,5io 

2! 

ig,53i 

31 

19,552 

20 

19,572 

21 

0,0961 

0,32 

20,010 

21 

2O,03l 

22 

20,o53 

22 

30,075 

21 

20,096 

22 

30,!  18 

21 

20,139 

22 

20,161 

21 

20,182 

21 

20,203 

33 

0,1024 

0,33 

20,635 

22 

20,657 

22 

30,679 

23 

30,703 

23 

20,724 

22 

30,746 

22 

20,768 

22 

20,7gc 

33 

20,812 

23 

20,835 

33 

o,io8g 

0,34 

21,260 

23 

21,283 

23 

3 1 ,3o6 

23 

31,339 

23 

21,352 

22 

21,374 

23 

21,397 

23 

2 1 ,420 

33 

21,443 

23 

21,466 

33 

0,1 156 

0,35 

21,885 

23 

3  1 ,908 

24 

21,932 

24 

21,956 

23 

21,979 

24 

22,003 

23 

32,026 

24 

22,o5o 

23 

22,073 

24 

33,097 

23 

0,1335 

0,36 

22,5lO 

24 

33,534 

24 

22,558 

25 

22,583 

24 

2  2 ,607 

24 

2  2 ,63  I 

24 

22,655 

24 

22,67g 

25 

22,704 

24 

33,738 

24 

0,1396 

0,37 

23,i35 

25 

33, 160 

25 

23,i85 

25 

23,210 

25 

33,335 

24 

23,25g 

25 

23,284 

25 

23,309 

25 

23,334 

25 

33,35g 

24 

0,1369 

o,38 

23,760 

25 

23,785 

26 

23,8ii 

26 

23,837 

25 

33,863 

26 

23,888 

25 

23,913 

26 

23,939 

25 

23,964 

26 

23,ggo 

25 

0,1444 

0,39 

24,385 

36 

24,411 

26 

34,437 

27 

34,464 

26 

34,490 

26 

24,5i6 

26 

24,542 

26 

24,568 

27 

24,595 

36 

24,621 

26 

0,l531 

o,4o 

25,009 

27 

25,o36 

27 

3  5,o63 

27 

25,090 

27 

35,117 

27 

25,i44 

27 

25,171 

27 

25,ig8 

27 

35,335 

27 

25,353 

26 

0,1600 

0,4 1 

25,634 

28 

25,663 

28 

25,690 

27 

35,717 

38 

25,745 

27 

25,772 

28 

25,800 

28 

25,828 

27 

35,855 

27 

35,883 

28 

0,1681 

0,42 

26,25g 

28 

36,387 

29 

26,3 16 

28 

36,344 

38 

26,372 

29 

26,401 

28 

36,43g 

28 

26,457 

38 

26,485 

28 

36,5i3 

38 

0,1764 

0,43 

26,884 

=9 

26,913 

29 

26,942 

29 

26,971 

29 

27,000 

29 

37,02g 

29 

37,o58 

29 

27,087 

38 

27,ii5 

29 

37,144 

29 

0,1849 

0,44 

27,509 

29 

27,538 

3o 

27,568 

3o 

27,598 

29 

27,627 

3o 

27,657 

29 

27,686 

3o 

27,716 

3o 

27,746 

29 

27,775 

29 

0,1  g36 

0,45 

28,i33 

3i 

28,164 

3o 

28,194 

3o 

28,224 

3i 

28,255 

3o 

28,385 

3o 

28,3i5 

3o 

28,345 

3i 

28,376 

3o 

28,406 

3o 

0,2025 

o,5o 

3i,256 

34 

31,290 

34 

3i,324 

34 

3 1, 358 

33 

3 1 ,39 1 

34 

3i,435 

34 

31,459 

33 

31,492 

34 

3 1, 526 

33 

31,559 

34 

0,2  5oo 

0,55 

34,378 

38 

34,416 

37 

34,453 

37 

34,490 

37 

34,527 

37 

34,564 

37 

34,601 

37 

34,638 

37 

34,675 

37 

34,712 

36 

o,3o25 

0,60 

37,499 

4i 

37,540 

4i 

37,581 

4o 

37,621 

4i 

37,662 

4o 

37,703 

40 

37,743 

4i 

37,783 

4o 

37,823 

4o 

37,863 

40 

o,36oo 

o,65 

4o,6ig 

Ai 

4o,663 

AA 

40,707 

AA 

4o,75i 

AA 

40,795 

AA 

4o,83g 

AA 

4o,883 

43 

40,936 

AA 

40,970 

AA 

4i,oi4 

43 

0,4225 

0,70 

43,738 

48 

43,786 

47 

43,833 

Ai 

43,880 

Ai 

43,927 

48 

43,975 

Ai 

44,022 

47 

44,069 

Ai 

44,116 

Al 

44,i63 

47 

o,4goo 

0,75 

46,856 

5o 

46,906 

5i 

46,957 

5i 

47,no8 

5i 

47,059 

5o 

47,109 

5i 

47,160 

5o 

47,210 

5o 

47,260 

5i 

47,3ii 

5o 

0,5625 

0,80 

49.972 

54 

50,026 

54 

5o,o8o 

54 

5o,i34 

54 

5o,i88 

54 

5o,343 

54 

50,396 

54 

5o,35o 

54 

5o,4o4 

54 

50.458 

53 

o,64oo 

0,85 

53,086 

58 

53,144 

58 

53,202 

57 

53,359 

57 

53,3i6 

58 

53,374 

57 

53,43i 

57 

53,488 

58 

53,546 

57 

53,6o3 

57 

0,7225 

0,90 

56,199 

61 

56,36o 

61 

56,321 

61 

56,383 

6r 

56,443 

61 

56,5o4 

61 

56,565 

60 

56,625 

61 

56,686 

60 

56,746 

61 

0,8100 

0,95 

59,3ii 

64 

59,375 

65 

59,440 

64 

59.504 

64 

59,568 

64 

59,633 

65 

59,697 

64 

59,761 

64 

5g,825 

63 

5g,888 

64 

0,9025 

1,00 

62,420 

68 

63,488 

68 

62,556 

68 

6 

2,624 

67 

62,691 

68 

63,759 

68 

63,837 

67 

62,894 

67 

62,961 

68 

63,02g 

67 

1 ,0000 

10,7185 

10,76481 

10,8113 

10,8578 

10,9045 

10,9512 

10,9981 

1 1 ,0450 

11,0921 

11,1392 

(? 

è  .  (r  +  r  "  )'     or    r=  +  J 

"^    nearly.                                                                                                      | 

624 

635 

626 

637 

628 

629 

63o 

63 1 

632 

I 

62 

63 

63 

63 

63 

63 

63 

63 

63 

I 

2 

125 

135 

125 

135 

126 

126 

126 

126 

126 

3 

3 

187 

188 

788 

188 

188 

i8g 

189 

189 

190 

3 

4 

25o 

25o 

2  5o 

25l 

25l 

252 

252 

253 

253 

4 

5 

3l2 

3i3 

3i3 

3i4 

3i4 

3i5 

3i5 

3i6 

3i6 

5 

6 

374 

375 

376 

376 

377 

377 

378 

379 

379 

6 

7 

437 

438 

438 

439 

440 

440 

44 1 

442 

442 

7 

8 

499 

5oo 

5oi 

502 

502 

5o3 

5o4 

5o5 

5o6 

8 

9 

562 

563 

56 

3 

5( 

54 

5 

65 

566 

567  1 

568  1 

569 

9 

TABLE   II.  —  To  find  the  time  T\  tlie  sum  of  the  radii  r-}-»' ",  and  tlie  cliord  c  beinf;  f^iven. 


Sum  of  llio  Kadii  r~\-r". 

r 

..p. 

imrl 

Itir 

llio 

bum 

ul  ll 

,,■  lit 

Jii. 

Cliuri 

4,7;j 

4,7-^ 

[         4,75 

4,76  1  4,77 

1  4,78 

OjOOtIO 

1  1  3  1  3  1  4  1  5  1  (i  1  7  1  8  1  g 

1 
2 
3 

0 
0 
0 

0 
0 

0 
I 
1 

0 

I 

I 

2 

I 
I 

3 

I 
I 
3 

I 
3 
3 

I 
2 
3 

C. 

Days  1 

lif.   Days  |i 

if.   Days  |d 

1'.    Days  1 

lir   Days  |(lif.  |  Days  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

o,ui 

o,632 

I  o,633 

I  o,634 

0  0,634 

1  o,635 

0  0,635 

I 

0,000 1 

4 

1 

2 

2 

2 

3 

3 

4 

0,02 

1,264 

3  1,366 

I   1,367 

1  1,368 

3  1,370 

I  1,271 

I 

o,ooo4 

o,o3 

1,896 

3   1,898 

2   I  ,QOO 

I   ■■9"' 

3   I  ,go4 

2  1 ,9o( 

2 

0,0009 

5 

2 

2 

3 

3 

4 

4 

5 

0,04 

2,529 

3   2,53l 

3  2,534 

3  2,537 

2  2,53g 

3  2,542 

3 

0,0016 

6 

2 
3 

3 

3 

3 

4 

4 

4 

4 

r 

5 
6 

5 
6 

0,uf> 

3,161 

3  3,164 

3  3,167 

4  3,171 

3  3,174 

3  3,177 

4 

0,0035 

8 

3 

2 

3 

4 

5 

() 

6 

7 

t),u6 

3,793 

4  3,-97 

4  3,801 

4  3,8o5 

4  3,8og 

4  3,8i3 

4 

o,oo36 

9 

3 

3 

4 

5 

5 

6 

7 

8 

0,07 

4,425 

5  4,43o 

4  4,434 

5  4,439 

5  4,444 

4  4,448 

5 

0,0049 

3 

0,0b 

5, 057 

5  5.063 

6  5,068 

5  5.073 

5  5,078 

6  5,084 

5 

0,0064 

10 

3 

4 

5 

6 

7 

8 

9 

o,oy 

5,689 

C  5,(^95 

6  5,701 

6  5,707 

6  5,7.3 

6  5,71g 

6 

0,008 1 

1 1 

13 

3 
3 

3 
4 

4 
5 

6 
6 

7 
7 

8 

8 

9 
10 

10 
1 1 

0,10 

6.321 

7  6,338 

7  6,335 

6  6,341 

7  6,348 

7  6,355 

6 

0,0100 

i3 
i4 

3 

3 

4 

5 
6 

7 

8 

9 

10 

12 
i3 

U,I  I 

6,o53 

8  6,961 

7  6,968 

7  6,975 

8  6,g83 

7  6,990 

7 

0,01  3  1 

4 

7 

8 

10 

II 

0,12 

7,586 

8  7.594 

8  7,603 

8  7,610 

8  7,618 

8  7,626 

8 

0,0144 

i5 

2 

3 

5 

6 

8 

9 
10 

1 1 

13 

'4 

û,i3 

8,218 

8  8,336 

9  8,335 

9  8,244 

8  8,252 

9  8,261 

9 

0,01 6g 

16 

2 

3 

5 

6 

8 

1 1 

i3 

'4 

0,14 

8,85o 

9  8,85g 

9  8,868 

10  8,878 

g  8,887 

9  8,896 

10 

0,01 96 

17 

3 

3 

5 

7 

g 

10 

12 

i4 

i5 

o,i5 

9,482 

10  9,492 

10  g,5o2 

10  9,5i3 

10  g,522 

10  9,532 

10 

0,0225 

18 
'9 

3 
2 

4 
4 

5 
6 

7 
8 

9 
10 

11 
1 1 

i3 
i3 

i4 
i5 

16 

17 

0,16 

io,ii4 

11  10,125 

10  io,i35 

II  io,i46 

II  io,i57 

10  10,167 

II 

o,o256 

0,17 

10.746 

11  10,757 

13  10,769 

II  10,780 

11  10,791 

12  io,8o3 

II 

0,0289 

30 

2 

4 

6 

8 

10 

13 

i4 

i6 

18 

O.ltl 

11,378 

12  11,390 

13  II,403 

12  ii,4i4 

12  II ,426 

12  11,438 

12 

o,o324 

31 

2 

4 

6 

8 

11 

i3 

i5 

'7 

'9 

o,iy 

12,010 

l3  12,023 

13  I3,035 

i3  12,048 

1 3  13,061 

12  12,073 

i3 

o,o36i 

33 

2 

4 

7 

9 

11 

i3 

i5 

18 

20 

33 

2 

5 

7 

9 

13 

i4 

16 

18 

21 

0,30 

12,642 

i3  13,655 

i4  i2,66g 

i3  13.683 

i3  12,695 

i4  12,709 

i3 

o,f>4oo 

24 

2 

5 

7 

10 

12 

i4 

17 

19 

22 

0,3 1 

i3,274 

14  i3,388 

i4  i3,3o2 

4  i3,3i6 

1 4  i3,33o 

i4  1 3,344 

i4 

0,044 1 

0,22 

13,906 

1 5  13.931 

14  i3,g35 

5  i3,g5ù 

1 5  13,965 

i4  13.979 

i5 

o,o484 

25 

36 

3 

5 

8 

10 

l3 

i5 

18 

30 

23 

0,23 

i4,538 

1 5  i4,553 

16  14,569 

5  i4,584 

i5  14,599 

16  f4,6i5 

i5 

o,o52g 

3 

5 

8 

10 

i3 

16 

18 

31 

23 

0,24 

15,170 

16  i5,i86 

16  l5,203 

6  i5,3i8 

16  i5,234 

16  i5,35o 

16 

0,0576 

27 

3 

5 

8 

u 

i4 

16 

'9 

33 

24 

38 

3 

6 

8 

1 1 

i4 

17 

20 

3  2 

25 

0,25 

1 5,802 

17  i5,8ig 

16  1 5,835 

7  1 5,852 

17  15,869 

16  i5,885 

17 

0,0625 

29 

3 

6 

9 

13 

i5 

17 

20 

33 

26 

0,26 

16,434 

17  i6,45i 

18  16,469 

7  16,486 

17  i6,5o3 

17  16,530 

18 

0,0676 

3o 

3 

6 

9 
9 
10 

I  3 

i5 

18 

3 1 

34 
25 
36 

27 
28 

59 

3o 

0,27 
0,28 

17,066 
17.698 

18  17,084 
18  17,716 

18  17,102 
ig  17,735 

8  17,120 

9  '7,754 

18  I7,i38 
18  17,772 

18  I7,i56 

19  17,79' 

18 
'9 

0,073g 
0,0784 

3i 

33 

3 
3 

6 
6 

12 

i3 

16 
16 

19 
19 
20 

2  3 
32 

0,2y 

i8,32g 

3o  i8,34g 

19  1 8,368  : 

0  i8,388 

19  18,407 

19  18,436 

19 

0,084 1 

33 

3 

7 

10 

i3 

17 

33 

36 

o,3o 

18,961 

20  18,981 

20  19,001  ; 

0  19,021 

20  19,041 

30  19,061 

30 

o,ogoo 

34 

3 

7 

10 

i4 

17 

20 

34 

27 

3i 

o,3i 

19,593 

31  ig,6i4 

20  19,634  2 

1  19,655 

21  19,676 

30  19,696 

31 

0,0961 

35 

4 

7 

II 

14 

18 

21 

35 

28 

32 

0,32 

20,225 

31  30,346 

33  20,268  3 

1  30,289 

21  20,3 10 

33  30,332 

31 

0,1024 

36 

4 

7 

1 1 

i4 

18 

23 

35 

29 

32 

0,33 

20.857 

33  20,879 

33  20,901  3 

2  20,933 

22  20,945 

2  2  20,967 

23 

0,1  o8g 

37 

4 

7 

II 

i5 

'9 

22 

36 

3o 

33 

0,34 

21,488 

23  2I,5ll 

33  21,534  3 

3  31,556 

33  31,57g 

33  3 1, 603 

23 

0,1 1 56 

38 

4 

8 

II 

i5 

'9 

23 

27 

3o 

34 

39 

4 

8 

12 

16 

30 

23 

27 

3i 

35 

0,35 

22,120 

24  33,l44 

23  22,167  a 

3  32,190 

34  22,214 

23  23,237 

23 

0,1335 

0,36 

23,752 

24  32,776 

24  22,800  2 

4  32,824 

24  22,848 

24  32,872 

34 

0,1296 

40 

4 

8 

12 

16 

30 

34 

38 

32 

36 

0,37 

23,383 

25  23,408 

25  23,433  2 

5  23,458 

24  33,483 

25  23,507 

34 

o,i3(k) 

4i 

4 

8 

12 

i(j 

21 

35 

29 

33 

37 

o,38 

24,01 5 

36  24,041 

3  5  34,066  3 

5  24.091 

36  34,117 

25  34,142 

25 

0,1 444 

43 

4 

8 

i3 

17 

31 

25 

29 

34 

38 

o,3g 

24,647 

26  34,673 

26  24,699  2 

6  34,735 

36  34,75i 

36  24,777 

26 

0,l52I 

43 

4 

9 

i3 

17 

33 

26 

3o 

34 

39 

44 

4 

9 

i3 

18 

33 

36 

3i 

35 

40 

o,4o 

25,278 

27  35,3o5 

J7  25,332   2 

7  25,35g 

26  25,385 

27  25,4l2 

26 

0,1600 

o,4i 

25,910 

i-j   35,937 

28  35,g65  2 

7  25,gg2 

i-j   36,01g 

!8  26,047 

27 

0,1681 

45 

5 

9 

i4 

18 

2  3 

27 

32 

36 

4i 

0,42 

26,541 

îg  26,570 

28   26,598  2 

8  26,626 

!8  26,654 

!8  26,683 

27 

0,1764 

46 

5 

9 

i4 

18 

23 

38 

33 

37 

4i 

0,43 

27.173 

!g  37,303 

18    27,230  3 

9  27,25g 

jg  27,288 

!8  37,3 1 6 

=9 

0,1849 

47 

5 

9 

i4 

19 

24 

38 

33 

38 

43 

0,44 

37,804 

3o  27,834 

!g  27,863  3 

0  27,893 

iQ   37,923 

!g  37,g5i 

3o 

0,1936 

48 

5 

10 

14 

'9 

34 

29 

34 

38 

43 

49 

5 

10 

i5 

20 

35 

29 

34 

39 

44 

0,45 

28,436  , 

ÎO  28,466  . 

ÎO  38,496  3 

0  28,526  . 

3o  28,556  . 

3o  38,586 

3o 

0,2025 

r 

35 
26 
36 

3o 
3i 
3i 

33 
33 

35 
36 
36 

37 
38 

4o 
4i 
42 

45 
46 

47 

48 
49 

o,5o 

3i,5g3  . 

Î3  31,626 

33  3 1, 659  3 

4  31,693  . 

33  31,726  . 

33  31,759 

34 

o,25oo 

5o 
5i 

53 

53 
54 

J 
r 

10 

i5 
i5 
16 
16 
16 

2C) 

0,55 

34,748 

37  34,785 

37  34,822  3 

7  34,859 

36  34,895  . 

37  34,933 

37 

o,3o2  5 

J 

5 

10 

20 

0,60 

37,903  ; 

U   37,944  < 

io  37,984  4 

0  38,024  t 

jo  38,o64  ^ 

fo  38,io4 

4o 

o,36oo 

r. 

10 

31 

0,65 

4i,o57  . 

i4  41.101  I 

<3  41, 144  4 

4  4i,i88  i 

i3  4i,23i  , 

i3  4 1, 274 

44 

0,4225 

f, 

1 1 

3  1 

27 

42 

43 

0,70 

44.210  1 

ij   44,257  I 

Î6  44, 3o3  4 

7  44,35o  i 

[7  44,397  i 

i7  44,444 

46 

0,4900 

J 

1 1 

22 

27 

0,75 

47,36i 

5o  47,4 1 1 

5i  47,462  5 

0  47,5i2  ' 

)o  47,562  t 

)0  47,612 

5o 

0,5625 

55 
56 

6 
6 

II 

17 
17 
17 
17 
18 

22 
22 

38 
38 

33 
34 

39 
39 
4o 
4i 

44 
45 

5o 
5o 

0,80 

5o,5ii 

54  5o,565 

53  5o,6i8  5 

4  50,673  ' 

)3  50,725  ; 

)4  5o,77g 

53 

0,6400 

57 
58 

6 

Ï I 

23 

29 

3^ 

M 

46 
46 

5i 

o,85 

53,660 

37  53,717 

J7  53,774  5 

7  53,83 1 

)6  53,887  ! 

>7   53,g44 

57 

0,7235 

6 

13 

33 

35 

53 

0,90 

56,8o7 

5o  56,867  ( 

3i  56,938  6 

0  56,988  ( 

io  57,048  ( 

X)  57,108 

60 

0,8100 

59 

6 

1  2 

34 

35 

4i 

47 

53 

o.gS 

59.953  ( 

Î4  60,016  ( 

54  60,080  6 

3  60,143  ( 

)4  60,207  t 

)3  60,270 

64 

o,go25 

1,00 

63,096  ( 

57  63,i63  f 

J7  63,33o  6 

7  63,397  ( 

>7  63,364  t 

)7  63,43 1 

67 

1 ,0000 

60 
61 
62 
63 
64 

6 
6 
6 
6 
6 

12 
12 
12 
l3 
l3 

18 
18 
'9 
19 
19 

24 
34 
35 
3  5 
36 

3o 
3i 
3i 

33 
33 

36 
37 
37 
38 
38 

42 
43 
43 
44 
45 

48 

49 
5o 
5o 
5i 

54 
55 
56 
57 
58 

11,186 

5  11,233 

8  ll,28i; 

3  11,328 

8  11,376 

5  11,42421 

\  .  {r  -\-  t")'*     or  r^-\-  r"^     nearly.                      | 

63 1 

632 

633 

634 

635 

636 







— ■ 





65 

7 

l3 

20 

36 

33 

39 

46 

53 

59 

I 

63 

63 

63 

63 

64 

64 

I 

66 

7 

i3 

20 

26 

33 

4o 

46 

53 

59 

2 

136 

126 

137 

127 

127 

137 

2 

67 

7 

i3 

20 

'7 

34 

40 

47 

54 

60 

3 

189 

I  go 

190 

190 

191 

191 

3 

68 

7 

14 

20 

27 

34 

4i 

48 

54 

61 

4 

353 

253 

353 

2  54 

254 

254 

4 

69 

7 

i4 

21 

38 

35 

4i 

48 

55 

62 

5 

3i6 

3i6 

3.7 

3t7 

3i8 

3i8 

5 

6 

379 

379 

38o 

38o 

38i 

382 

6 

70 

7 

i4 

21 

38 

35 

43 

49 

56 

63 

7 

442 

442 

443 

444 

445 

445 

7 

80 

8 

16 

24 

33 

4o 

48 

56 

M 

72 

8 

5o5 

5o6 

5o6 

5o7 

5o8 

5og 

8 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

9 

568 

569 

670 

571 

572 

572 

9 

00 

0 

20 

3o 

4o 

5o 

60 

7" 

80 

9°! 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r  +  >■".  and  the  chord  e  being  given. 


t>uin  of  llie  Railii  r  -\-  r".                                                                                                            1 

Chord 
C. 

4,79 

4,80 

4,81 

4,82    1 

4,83 

4,84 

4,85 

4,86 

4,87    1 

4,88 

Days  |.l(l'. 

Days  Idir. 

Days  1.1  if. 

Days  1 

dif. 

Days  Idif. 

Uaya  |dir. 

Tj^sfdrr. 

Days  Irtif. 

Day 

3  |dif. 

Daya  |dif. 

0,00 

0,000 

0,000 

0,0(Ki 

0,000 

0,000 

0,000 

0,000 

0,00 

0 

0,0c 

0 

0,000 

0,0000 

0,01 

o,636 

I 

o,637 

0 

",637 

I 

0,638 

I 

0,639 

0 

0,639 

I 

0,640 

I 

0,64 

I     0 

0,64 

1        I 

0.642 

I 

0,0001 

0,0  a 

1,279 

2 

1,274 

I 

1,275 

I 

1,276 

3 

1,278 

I 

1,279 

1 

1,280 

2 

I,2& 

2     I 

1,28 

3      t 

1,284 

2 

0,0004 

o,o3 

i,go8 

2 

1,910 

2 

1,912 

2 

1.914 

2 

1.916 

2 

i,gi8 

2 

1,920 

2 

1,92 

2     2 

1,93 

4     2 

1,926 

2 

o,ooog 

0,04 

2,545 

3 

2,547 

3 

2,55o 

3 

2,553 

3 

2;555 

3 

2,558 

2 

2,56o 

3 

2,56 

3      3 

2,56 

6     2 

2,568 

3 

0,0016 

o,o5 

3,181 

3 

3,184 

3 

3,187 

4 

3,191 

3 

3,194 

3 

3,197 

4 

3,201 

3 

3,2c 

4     3 

3,20 

7      3 

3,310 

4 

0,0025 

0,06 

3,817 

4 

3,821 

4 

3,825 

4 

3,82g 

4 

3,833 

4 

3,837 

4 

3,84i 

4 

3,84 

5     4 

3,84 

9     4 

3,853 

3 

o,oo36 

0,07 

4,453 

5 

4,458 

4 

4,462 

5 

4,467 

5 

4,472 

4 

4,476 

5 

4,481 

4 

4,48 

5     5 

4,4g 

0     5 

4,495 

4 

o,oo4g 

0,08 

5,089 

5 

5,094 

6 

5,100 

5 

5,io5 

5 

5,110 

6 

5,116 

5 

5.121 

5 

5.12 

6     5 

5,i3 

1      6 

5,i37 

5 

0,0064 

0,09 

5,725 

6 

5,73. 

6 

5,737 

6 

5,743 

6 

5,74g 

6 

5,755 

6 

5^761 

6 

5;7e 

7      6 

5,77 

3     6 

5,779 

6 

0,0081 

0,10 

6,36i 

T 

6,368 

7 

6,375 

6 

6,38 1 

7 

6,388 

6 

6,3g4 

-1 

6,4oi 

7 

6,4c 

8     6 

6,4 1 

4     7 

6,421 

6 

0,0100 

o,i  I 

6,997 

8 

7, 00  5 

7 

7 .0 1 3 

7 

7,oig 

8 

7,027 

7 

7,"34 

7 

7,o4i 

7 

7,0-j 

8      8 

7,o5 

6     7 

7, 06  3 

7 

0,0121 

0,12 

7,634 

7 

7,64 1 

8 

7,649 

8 

7,657 

8 

7,665 

8 

7,673 

8 

7,681 

8 

7,6fc 

9      8 

7,6cj 

7      8 

7,705 

8 

0,0144 

0,1 3 

8,270 

8 

8,278 

9 

8,28-j 

9 

8.996 

8 

8,3o4 

9 

8,3 1 3 

8 

8,321 

9 

8,3: 

0     8 

8,33 

8      9 

8,347 

9 

0,0 1 6g 

0,1 4 

8,906 

9 

8,915 

9 

8,924 

10 

8,934 

9 

8,g43 

9 

8,953 

9 

8,y6i 

10 

8,9- 

■      9 

8,98 

"      9 

8.98g 

9 

0,0196 

0,1 5 

9.'^42 

10 

9,559 

10 

9,563 

10 

9,572 

10 

g,582 

9 

9,59' 

10 

9,601 

10 

9.61 

I    10 

g.69 

1      IO 

g,63i 

10 

0,0225 

0,16 

10,178 

10 

10,188 

II 

10,199 

11 

10,210 

10 

10,330 

11 

IO,23l 

10 

10,241 

1 1 

10,3^ 

2    II 

IO,2f 

3    10 

10,273 

1 1 

o,o256 

0,17 

10,814 

II 

10,825 

1 1 

io,836 

13 

io,848 

II 

10,8  5g 

1 1 

10,870 

1 1 

10,881 

19 

10,8c 

3    II 

io,gr 

4    11 

io,gi5 

II 

0,0289 

o,i3 

I  i,45o 

13 

11,462 

13 

11,474 

13 

11,486 

12 

1 1 ,498 

12 

1 1, 5 10 

II 

11,521 

19 

11,5; 

3      19 

■  ■,5^ 

5    12 

11,557 

12 

o,o324 

0,19 

12,086 

i3 

12,099 

13 

12,11 1 

i3 

12,124 

12 

I2,i36 

i3 

12,149 

13 

l2,lGl 

i3 

r2,i- 

4      19 

I2,lt 

6    i3 

12,199 

12 

o,o36i 

o,ao 

19,723 

i3 

12,735 

i4 

■2,749 

i3 

12,762 

1 3 

12,775 

i3 

12,788 

i3 

I  2 .80 1 

■  4 

12,8 

5    i3 

12,83 

8    i3 

i2,84i 

i3 

o,o4oo 

0,21 

i3,358 

i4 

13,372 

i4 

i3,386 

i4 

1 3,400 

14 

i3,4i4 

1 4 

13,428 

i3 

■  3,44i 

i4 

i3,4' 

5    14 

1 3,4c 

9    i4 

13483 

i4 

0,044 1 

0,22 

1 3,994 

i5 

14,009 

i4 

l4,023 

i5 

i4,o38 

■  4 

i4,o52 

15 

14,067 

i4 

14,081 

i5 

1 4,0c 

)6    14 

i4,i  I 

0    i5 

i4,i25 

i4 

0,0484 

0,23 

i4,63o 

i5 

i4,645 

i5 

1 4,660 

16 

14,676 

i5 

■  4,691 

i5 

14.706 

i5 

14,72  ■ 

i5 

■  4,7^ 

Î6    16 

■  4,7' 

2    i5 

14.767 

i5 

0,0529 

0,24 

1 5,266 

16 

15,283 

16 

15,298 

16 

i5,3i4 

16 

i5,33o 

i5 

■  5,345 

16 

i5,36i 

16 

i53- 

7    16 

1 5,3c 

3    16 

1 5,409 

i5 

o,o5-6 

0,25 

i5,go9 

16 

1 5,91 8 

17 

■5,935 

■7 

1 5,953 

16 

15,968 

17 

1 5,985 

16 

i6/)oi 

17 

16,0 

8    16 

i6,o' 

4    17 

i6,o5i 

16 

0,0625 

0,26 

i6,538 

■7 

16,555 

17 

16,573 

17 

16,589 

18 

16,607 

17 

16,624 

■  7 

16,64 1 

17 

16,6: 

8    17 

16,6- 

5    17 

16.692 

18 

0,0676 

0,27 

17.174 

18 

17,192 

17 

17,209 

18 

■  7.237 

18 

17,245 

18 

17,263 

18 

17,281 

18 

17,2c 

)9    18 

■7,3 1 

7     17 

17,334 

18 

0,0739 

0,28 

17,810 

18 

17,838 

'9 

17-847 

18 

17,865 

■9 

17,884 

18 

■  7,912 

■9 

17.921 

18 

17,9' 

9    19 

i7,g- 

8    18 

i7-g76 

■9 

0,0784 

0,2g 

18,445 

30 

i8,465 

19 

■  8,484 

'9 

i8,5o3 

ig 

l8,523 

■9 

i8,54i 

20 

i8,56i 

■9 

i8,5t 

io     I  g 

iS,5ç 

9    '9 

18,618 

■9 

o,o84i 

o,3o 

19,081 

20 

19,101 

30 

ig,i2i 

20 

ig,i4i 

90 

19,161 

20 

ig.tSi 

19 

19.200 

20 

19,2: 

0     90 

■9-2- 

0    20 

ig,26o 

■9 

0,0900 

0,3 1 

I9'7I7 

21 

19,738 

30 

19,758 

21 

■  9.779 

20 

■9.799 

21 

19,820 

20 

19,840 

21 

i9,8( 

)I      20 

ig,8f 

1    21 

19,903 

20 

0,0961 

0,32 

30,353 

21 

90,374 

21 

90,395 

23 

30,4l7 

91 

2o,438 

21 

20,459 

21 

30,480 

21 

90, 5c 

)I      91 

20, 5; 

3    21 

20,543 

21 

0,1034 

0,33 

30,989 

23 

2 1 ,0 1 1 

21 

9  1,o32 

9  9 

2  r  ,o54 

22 

3 1 ,076 

29 

2 1 ,098 

99 

21,190 

22 

i\,\i 

9      91 

21, if 

3    22 

2i,i85 

22 

0,1089 

0,34 

21,624 

23 

21,647 

23 

2 1  ,670 

23 

3 1 ,693 

23 

21,715 

22 

21,737 

93 

2 1 ,760 

22 

2i,7f 

i9      23 

2 1, 8c 

4     23 

21,827 

22 

0,1 1 56 

0,35 

22,360 

23 

32,283 

24 

22,307 

2  3 

2  2,33o 

23 

23,353 

23 

29,376 

23 

29,3gg 

23 

224 

2      23 

22^:!^ 

'5    23 

22,468 

23 

0,1335 

o,36 

22,896 

24 

32,920 

24 

22,g44 

23 

2  2 ,967 

24 

3  3,ggi 

24 

33,oi5 

24 

2  3,o3g 

24 

23,of 

>3      23 

2  3, of 

G    24 

23,1 10 

24 

0,1296 

0,37 

23,53 1 

25 

23,556 

25 

33,58i 

24 

33,6o5 

2  5 

2  3,63o 

24 

2  3,654 

3  5 

23,679 

24 

23.7c 

j3    34 

23,7: 

7     25 

23,752 

24 

0,1369 

o,38 

24,167 

25 

24,199 

36 

34,218 

25 

24.243 

25 

34,268 

25 

24,2g3 

35 

24.3 1 S 

25 

24,3. 

f3    2  5 

24,3t 

)8    25 

24,393 

25 

0,1 444 

0,39 

24,8o3 

26 

24,829 

36 

24,855 

25 

34y88o 

26 

24,906 

26 

24,932 

26 

24,958 

26 

24,9* 

i4   25 

2  5,0c 

9    26 

25,o35 

26 

0,l52I 

o,4o 

25,438 

27 

3  5,465 

26 

25,491 

27 

35,5i8 

27 

25,545 

26 

25,571 

26 

25,597 

27 

25,6 

4    26 

25,6: 

0    27 

25,677 

26 

0,1600 

0,4 1 

36,074 

27 

26,101 

27 

36.128 

28 

36,1 56 

27 

26,183 

27 

26,210 

27 

26.237 

27 

26,9( 

54    27 

26,9c 

I    ii 

26,318 

27 

0,1681 

0,42 

26,709 

28 

26,737 

28 

26,765 

28 

26,793 

28 

96,821 

28 

26,849 

27 

26,876 

28 

26,91 

.4    28 

26,g" 

2    28 

26,960 

27 

0,1764 

0,43 

27,345 

29 

27,374 

28 

27,402 

29 

27,431 

28 

27,45g 

29 

27,488 

28 

27.516 

28 

27,5. 

i4    29 

27.5- 

3    28 

27,601 

28 

0,1 84g 

0,44 

27,981 

=9 

28,010 

29 

28,039 

29 

28,068 

29 

28,og7 

29 

28,126 

29 

28,155 

29 

28,1! 

M    3o 

28,2 

4    29 

28,243 

28 

0,1  g36 

0,45 

98,616 

3o 

28,646 

3o 

38,676 

3c 

28,706 

29 

28,735 

3o 

38,765 

3o 

28,795 

3o 

38,8 

25    2g 

38,8 

)4   3o 

28,884 

3o 

O,3035 

o,5o 

31,793 

33 

3 1 ,826 

33 

31.859 

33 

3 1, 893 

33 

31.995 

34 

31,959 
35,1 5 1 

33 

31,993 

33 

32,0 

!5    33 

32,0 

)8    33 

32.ogi 

33 

o,25oo 

0,55 

34,969 

36 

35,oo5 

37 

35,049 

36 

35,078 

37 

35;ii5 

36 

36 

35,187 

37 

35,3 

!4    36 

35,2f 

)o    36 

35,996 

37 

o,3o25 

0,60 

38,i44 

4o 

38,i84 

39 

38,333 

4' 

38.263 

4o 

38,3o3 

4o 

38,343 

39 

38,389 

40 

38,4 

22    40 

38, 4( 

>2    39 

38,5oi 

40 

o,36oo 

o,65 

4i,3i8 

43 

4i,36i 

43 

4 1 ,4o4 

43 

4 1, 447 

43 

41,490 

43 

41,533 

43 

41,576 

43 

4i,6 

g  A'i 

4i,6f 

)2      43 

4 1, 70  5 

43 

0,4225 

0,70 

44,49" 

47 

44,537 

46 

44383 

47 

44,63o 

46 

44,676 

47 

44.723 

46 

44,76g 

46 

44,8 

5   47 

44,8f 

J2      46 

44,go8 

46 

0,4900 

0,75 

47.662 

5o 

47.7 1 2 

5o 

47,762 

5o 

47,812 

4g 

47,861 

5o 

47,gii 

5o 

47 ,9'' ■ 

49 

48 ,0 

0    5o 

48, of 

5o   49 

48,iog 

5o 

o,5625 

0,80 

5o,832 

53 

5o,885 

54 

5o,g39 

53 

5o,gg3 

53 

5 1, 045 

53 

5 1 .09S 

53 

5i.i5i 

53 

5 1,2 

d4    53 

5l,2 

J7    53 

5i,3io 

52 

0,6400 

o,85 

54,00  T 

57 

54,o58 

56 

54,  ■M 

57 

54,i7i 

56 

54,227 

57 

54,284 

56 

54,340 

56 

54,3< 

)6    56 

54,4 

52    57 

54,509 

56 

0,7225 

0,90 

57,168 

60 

57,228 

60 

57,288 

60 

57,348 

60 

57,4o8 

60 

57,468 

59 

57,527 

60 

57,5 

il    59 

57,6 

\&   60 

57,706 

r? 

0,8100 

0,95 

60,334 

63 

60,397 

64 

60,461 

63 

60,52^ 

63 

60,587 

63 

6o,65o 

63 

60,71 3 

63 

60,7 

76   63 

60,8 

39    63 

60,902 

63 

o,go35 

1,00 

63,498 

67 

63,565 

66 

63,63 1 

67 

63,698 

66 
62 

63,76/ 

67 

63,83 1 

66 

63,897 

67 

63,9 

54    66 

64, 0 

3o    66 

64 ,096 

66 

1 ,0000 

1 1 ,4721 

11,5200 

11,5681 

1 1  ,'6" 

11,6645 

11,7128 

11,7613 

11,8098 

11,8585111,9072 

<? 

r   .    (  r  -f-  r"  j^      or      r^   -j-  r"  '^     nearly. 

1 

635 

63( 

)               637 

638 

639 

(i4o 

64 1 

642 

643 

I 

64 

%i 

i               64 

64 

64 

^64 

~A 

64 

&A 

I 

Î 

127 

12- 

127 

138 

128 

128 

128 

128 

12g 

3 

3 

'9' 

191 

191 

igi 

192 

192 

192 

193 

,93 

3 

4 

254 

25^ 

!              255 

255 

2  55 

256 

256 

257 

257 

4 

5 

3i8 

3iS 

319 

3i9 

320 

320 

321 

321 

322 

5 

6 

38 1 

38: 

382 

383 

383 

384 

385 

385 

386 

6 

7 

445 

44' 

446 

447 

447 

448 

449 

449 

45o 

7 

8 

5o8 

5oc 

)               5io 

5io 

5ii 

5l2 

5i3 

5i4 

5i4 

8 

9 

572 

57: 

5- 

?3 

t 

74 

S- 

.75 

576 

577 

578 

579 

9 

TABLE  II.  —  Toliiul  tlic  time  T;  the  sum  of  the  vailii  r- 


-)■'',  and  the  chord  e  being  given. 


Sum  ut'  iho  [iQ'lii  r-f-r". 


Clioiil 

4,8i) 

4,90 

4,91 

4,92 

4,93 

4,94 

c. 

l);iys  Iclif. 

Days  lUif. 

Buys  |(lil'. 

Days  |dif. 

Days  lilir. 

Duys  l.lir. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

o.oot» 

0,0000 

0,01 

0,643 

0 

0,643 

I 

0,644 

I 

o,645 

0 

0,645 

1 

0,646 

I 

0,0001 

0,05 

1 ,286 

I 

1,287 

I 

1,28s 

1 

1,289 

2 

1,291 

1 

1,392 

I 

0,0004 

o,o3 

1,928 

2 

1,930 

2 

1.933 

3 

1,934 

2 

1 ,936 

2 

i.g38 

3 

o,ooog 

o,o4 

2,571 

3 

2,574 

2 

2,576 

3 

2,579 

2 

2,58i 

3 

2,584 

3 

0,0016 

o,o5 

3,2i4 

3 

3,217 

3 

3,230 

4 

3,224 

3 

3,227 

3 

3,23o 

3 

0,0025 

0,06 

3,85() 

4 

3,860 

4 

3,864 

4 

3,868 

4 

3,872 

4 

3,876 

4 

o,oo36 

0,07 

4,490 

5 

4,5o4 

4 

4,5o8 

5 

4,513 

5 

4,5i8 

4 

4,522 

5 

0,0049 

0,08 

5,142 

5 

3,147 

5 

5,i52 

6 

5,1 58 

5 

5,i63 

5 

5,168 

5 

0,0064 

0,09 

5,785 

6 

5,791 

5 

5,79(5 

6 

5,802 

6 

5,808 

6 

5,8i4 

6 

0,008 1 

o,io 

0,427 

7 

6,434 

7 

6,441 

6 

6,447 

7 

6,454 

6 

6,460 

7 

0,0100 

0,1 1 

7,070 

7 

7>077 

8 

7,o85 

7 

7,092 

7 

7,099 

7 

7,106 

7 

0,0121 

0,12 

7,7"  3 

8 

7,721 

8 

7,729 

7 

7,736 

8 

7,744 

8 

7,752 

8 

o,oi44 

o,i3 

8,356 

8 

8,364 

9 

8,37! 

8 

8,38 1 

9 

8,390 

8 

8,398 

9 

0,0169 

o,i4 

8:99» 

9 

9.-O07 

10 

9,<"7 

9 

9,026 

9 

9,o35 

9 

9,044 

9 

0,01 96 

0,1 5 

9,64 1 

10 

9,65 1 

10 

9,66 1 

9 

9,670 

10 

9,680 

10 

9690 

10 

0,0225 

0,16 

10,284 

10 

10,294 

II 

io,3o5 

10 

io,3i5 

II 

10,326 

10 

io;336 

10 

o,o256 

0,17 

10,926 

II 

10.937 

12 

10,949 

II 

10,960 

II 

10,971 

II 

10,982 

11 

0,038g 

0,18 

11,569 

12 

ii,58i 

12 

11,593 

1 1 

1 1 ,604 

12 

11,616 

12 

11,628 

12 

o,o324 

0,19 

12,211 

i3 

12,224 

12 

12,236 

i3 

12,249 

12 

12,261 

i3 

12,274 

12 

o,o36 1 

0,30 

12.854 

1 3 

12,867 

i3 

12,880 

i4 

12,894 

i3 

12,907 

i3 

12,920 

i3 

o,o4oo 

0,21 

1 3,497 

i4 

i3,5ii 

i3 

i3,524 

14 

i3,538 

i4 

i3,552 

14 

1 3,566 

i3 

0,044 1 

0,22 

i4,i39 

i5 

i4,i54 

i4 

i4,i68 

i5 

i4,i83 

14 

14,197 

14 

l4,2II 

i5 

o,o484 

0,23 

14,782 

i5 

14,797 

i5 

i4,8i2 

i5 

14,827 

i5 

i4,842 

i5 

i4,85; 

i5 

0,0529 

0,24 

15,424 

16 

i5,44o 

16 

1 5,456 

16 

15,472 

16 

1 5,488 

i5 

i5,5o3 

16 

0,0576 

0,25 

1 6,067 

16 

i6,o83 

17 

16,100 

16 

16,116 

17 

i6,i33 

16 

16,149 

16 

0,0625 

0,26 

16,710 

17 

16,727 

17 

16,744 

17 

16,761 

17 

16,778 

17 

16,795 

17 

0,0676 

0,27 

17,352 

18 

17,370 

18 

17,388 

17 

i7,4o5 

18 

17,423 

18 

17,441 

17 

0,072g 

0,28 

17,995 

18 

i8,oi3 

18 

i8,o3i 

■9 

i8,o5o 

18 

18,068 

18 

18,086 

19 

0,0784 

0,29 

18,637 

'9 

1 8,656 

'9 

18,675 

'9 

i8,6g4 

19 

18,713 

19 

18,732 

19 

0,084 1 

o,3o 

'9^'79 

20 

I9-299 

20 

19,319 

30 

19,339 

19 

19,358 

20 

19,378 

19 

0,0900 

0,3 1 

19,922 

20 

19,942 

21 

19,963 

30 

19,983 

30 

30,Oo3 

21 

20,024 

20 

0,0961 

0.32 

20, 564 

21 

20,585 

21 

30,606 

31 

20,627 

31 

30/348 

21 

20,669 

21 

0,1024 

0,33 

21,207 

21 

21,228 

22 

3I,25o 

22 

21,272 

31 

21,293 

22 

2i,3i5 

22 

o,io8g 

0,34 

21,849 

22 

21,871 

23 

31,894 

22 

2i,gi6 

22 

21,938 

33 

2i,g6i 

22 

0,11 56 

0,35 

22,491 

23 

22,5l4 

23 

22,537 

23 

22,56o 

23 

22,583 

33 

22,606 

23 

0,1225 

o,36 

23,i34 

23 

33,157 

34 

23,181 

34 

23,2o5 

23 

23,228 

24 

23,253 

23 

0,1296 

0,37 

23,776 

24 

33,800 

25 

33,835 

24 

23.849 

34 

33,873 

24 

23,897 

25 

0,1369 

o,38 

24,418 

25 

54,443 

25 

34,468 

25 

24,493 

25 

24,5i8 

25 

24,543 

25 

0,1 444 

o,3g 

25,061 

25 

25,086 

26 

25,113 

25 

25,i37 

26 

25,i63 

26 

25,189 

25 

0,l52I 

o,4o 

2  5,7o3 

26 

25,729 

26 

25,755 

27 

25,782 

36 

25,808 

26 

25,834 

26 

0,1600 

0,4 1 

26.345 

27 

26,372 

27 

26,399 

27 

26,436 

27 

26,453 

27 

26,480 

36 

0,1681 

0,42 

26,987 

28 

27,01 5 

27 

27,042 

28 

27,070 

28 

27,098 

27 

27,135 

27 

0,1764 

0,43 

27,629 

59 

27,658 

28 

27,686 

28 

27,714 

28 

27,742 

28 

27,770 

29 

0,1849 

0,44 

28,271 

29 

28,300 

29 

28,329 

29 

38,358 

29 

28,387 

29 

28,416 

29 

o,ig36 

0,45 

28.914 

29 

28,943 

3o 

28,973 

29 

39,003 

3o 

29,033 

29 

29,061 

3o 

0,2025 

o,5o 

32.124 

32 

32.156 

33 

32,i8q 

33 

33.332 

33 

32,255 

33 

33,388 

32 

o,25oo 

0,55 

35.333 

36 

35;369 

36 

35,4o5 

36 

35:44. 

36 

35,477 

36 

35,5i3 

36 

o,3o35 

0,60 

38,54 1 

39 

38,58o 

4o 

38,620 

39 

38,659 

39 

38,698 

40 

38,738 

39 

o,36oo 

o,65 

4 1, 748 

43 

41,791 

42 

4 1, 833 

43 

41,876 

43 

41,919 

43 

41,961 

43 

0,4225 

0,70 

44:954 

46 

45,000 

46 

45,046 

46 

45,093 

46 

45,i38 

46 

45,184 

46 

0,4900 

0,75 

48,1 59 

49 

48.208 

5o 

48,258 

49 

48,3o7 

49 

48,356 

49 

48,4o5 

5o 

0,5635 

0,80 

5 1, 362 

53 

5i;4i5 

53 

5 1, 468 

52 

5i,52o 

53 

51,573 

53 

51,626 

52 

o,64oo 

0,85 

54,565 

56 

54,621 

56 

54,677 

56 

54,733 

55 

54,788 

56 

54,844 

56 

0,7325 

0,90 

57,765 

60 

57,835 

59 

57,884 

59 

57,943 

59 

58,002 

60 

58,o63 

59 

0,8100 

0,95 

60.965 

62 

61,027 

63 

61,090 

62 

6i,i52 

63 

6i,2i5 

63 

61,277 

63 

0,9035 

1,00 

64.162 

66 

64,228 

66 

64,294 

66 

64,36o 

66 

64.426 

66 

64,4g3 

65 

1 ,0000 

1 1 .9.: 

.61 

12,0c 

)50 

12,0E 

>41 

12,H 

);32 

V2,\l 

Î25 

i2;2f 

)18 

~?~ 

642 

64 
128 
193 
257 

331 

385 
449 
5i4 

5-S 


643 

64 
129 
193 

257 

322 

386 
45o 
5i4 


644 

64 
129 
193 
258 

322 

386 
45 1 
5i5 

58o 


nenrly. 

645 

65 
129 
194 
258 
323 
387 
452 
5i6 
58 1 


646 

65 
I2g 
194 
258 
323 
388 
452 
5i7 
58 1 


Prop. 

turts  fur  tlin  sum  ui'  tliu  Itiulii.  | 

■  1 

2  3  1  4  1  5  1  6  1  7  1  8 

_9 

I 

0 

0 

0 

0 

I 

I 

I 

I 

I 

2 

0 

0 

I 

I 

I 

I 

I 

2 

2 

3 

0 

I 

I 

I 

2 

2 

2 

2 

3 

4 

0 

I 

I 

2 

2 

2 

3 

3 

4 

5 

1 

3 

2 

3 

3 

4 

4 

5 

6 

I 

2 

2 

3 

4 

4 

5 

5 

7 

I 

2 

3 

4 

4 

5 

6 

6 

8 

2 

2 

3 

4 

5 

6 

6 

7 

9 

3 

3 

4 

5 

5 

6 

7 

8 

10 

2 

3 

4 

fj 

6 

7 

8 

9 

1 1 

2 

3 

4 

(> 

7 

8 

9 

10 

1 3 

2 

4 

5 

6 

7 

8 

10 

1 1 

i3 

3 

4 

5 

7 

8 

9 

10 

12 

i4 

3 

4 

0 

7 

8 

10 

1 1 

i3 

i5 

3 

3 

5 

6 

8 

9 

I  I 

12 

i4 

16 

2 

3 

5 

6 

8 

10 

I  I 

i3 

i4 

'7 

3 

3 

5 

7 

g 

10 

13 

i4 

i5 

18 

2 

4 

5 

7 

9 

1 1 

i3 

i4 

16 

19 

2 

4 

6 

8 

!0 

1 1 

i3 

i5 

17 

20 

2 

4 

6 

8 

10 

12 

i4 

16 

18 

21 

2 

4 

6 

8 

1  1 

i3 

i5 

17 

'9 

22 

2 

4 

7 

9 

I  1 

i3 

i5 

18 

30 

23 

3 

5 

7 

9 

12 

i4 

16 

18 

31 

24 

2 

5 

7 

10 

I  2 

i4 

17 

■9 

33 

25 

3 

5 

8 

10 

l3 

i5 

18 

20 

33 

26 

3 

5 

8 

10 

i3 

16 

18 

21 

23 

27 

3 

5 

8 

1 1 

i4 

16 

>9 

22 

24 

28 

3 

6 

8 

1 1 

i4 

17 

20 

23 

25 

29 

3 

6 

9 

12 

i5 

17 

20 

23 

26 

3o 

3 

6 

g 

12 

i5 

18 

21 

24 

27 

3i 

3 

6 

9 

1 2 

16 

'9 

22 

25 

28 

32 

3 

6 

10 

i3 

16 

19 

23 

26 

29 

33 

3 

7 

10 

i3 

17 

20 

33 

26 

3o 

34 

3 

7 

10 

i4 

17 

20 

24 

27 

3i 

35 

4 

7 

1 1 

14 

18 

21 

25 

28 

32 

36 

4 

7 

1 1 

i4 

18 

22 

25 

29 

32 

37 

4 

7 

1 1 

i5 

19 

22 

26 

3o 

33 

38 

4 

8 

II 

i5 

19 

23 

27 

3o 

34 

39 

4 

8 

13 

16 

20 

23 

27 

3i 

35 

40 

4 

8 

12 

16 

20 

24 

28 

32 

36 

4i 

4 

8 

12 

16 

21 

25 

29 

33 

37 

42 

4 

8 

l3 

17 

21 

25 

29 

34 

38 

43 

4 

9 

l3 

17 

23 

26 

3o 

34 

39 

44 

4 

9 

i3 

18 

22 

26 

3i 

35 

40 

45 

5 

9 

i4 

18 

33 

27 

32 

36 

4i 

46 

5 

9 

i4 

18 

23 

28 

32 

37 

4i 

47 

5 

g 

i4 

19 

24 

28 

33 

38 

42 

48 

5 

10 

i4 

19 

24 

29 

34 

38 

43 

49 

5 

10 

i5 

20 

35 

29 

34 

39 

44 

5o 

5 

10 

i5 

20 

35 

3o 

35 

4o 

45 

5i 

5 

10 

i5 

20 

26 

3i 

36 

4i 

46 

52 

5 

10 

16 

21 

26 

3i 

36 

42 

47 

53 

5 

1 1 

16 

21 

27 

32 

37 

42 

48 

54 

5 

1 1 

16 

22 

27 

32 

38 

43 

49 

55 

6 

1 1 

17 

32 

28 

33 

39 

44 

5o 

56 

6 

1 1 

17 

22 

28 

34 

39 

45 

5o 

57 

6 

1 1 

17 

23 

29 

34 

4o 

46 

5i 

58 

6 

12 

17 

23 

29 

35 

4i 

46 

52 

59 

6 

12 

18 

24 

3o 

35 

4i 

47 

53 

60 

6 

12 

18 

24 

3o 

36 

42 

48 

54 

61 

6 

13 

18 

24 

3i 

37 

43 

49 

55 

62 

6 

12 

'9 

35 

3i 

37 

43 

5o 

56 

63 

6 

l3 

19 

25 

33 

38 

44 

5o 

57 

64 

6 

i3 

19 

26 

32 

38 

45 

5i 

58 

65 

7 

i3 

20 

26 

33 

39 

46 

5: 

5g 

66 

7 

i3 

20 

26 

33 

40 

46 

53 

59 

67 

7 

i3 

20 

27 

34 

4o 

47 

54 

60 

68 

7 

i4 

20 

27 

34 

4i 

48 

54 

61 

69 

7 

i4 

21 

28 

35 

4i 

48 

55 

62 

70 

7 

i4 

31 

28 

35 

42 

49 

56 

63 

80 

8 

16 

24 

32 

40 

48 

56 

64 

72 

90 

9 

18 

27 

36 

45 

54 

63 

72 

81 

1  (10 

10 

30 

3o 

4o 

5o 

60 

70 

80 

go 

lis 


TABLE 

II. 

—  To  find  the  time 

T; 

the  sum  of  the  rac 

iir 

4-,-",  and 

the  chord  ( 

being  given. 

Chord 
C. 

4,95 

4,96 

4,97 

Days  IJil'. 

4,98 

4,99 

5,00 

5,01 

5,02 

5,03 

5,04 

Days  |(lil". 

Days  Idir. 

Days  |dif. 

Days  |ilir. 

Daysldif. 

Days  |dif. 

Daysldif. 

Days  Idif. 

Days  |dif. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

0,647 

0 

0,647 

I 

o,648 

1 

0,649 

0 

0,649 

I 

o,65o 

I 

o,65i 

0 

o,65i 

I 

o,652 

I 

o,653 

0 

0,0001 

0,02 

1,293 

2 

1,295 

I 

1 ,296 

I 

1,297 

2 

1,299 

I 

i,3oo 

1 

i,3oi 

1 

I,302 

2 

1 ,3o4 

I 

i,3o5 

1 

0,0004 

o,o3 

1 .940 

2 

1.942 

2 

1,944 

2 

1,946 

2 

1,948 

3 

i,95o 

3 

1,952 

2 

1.954 

3 

1,956 

3 

1,958 

2 

0,0009 

o,o4 

2,587 

2 

2,589 

3 

2,592 

3 

2,595 

2 

2,597 

3 

2,600 

2 

2,602 

3 

3,6o5 

3 

2,608 

3 

2,610 

3 

0,0016 

o,o5 

3,233 

4 

3,237 

3 

3,240 

3 

3,243 

3 

3,246 

4 

3,25o 

3 

3,253 

3 

3,356 

3 

3.25g 

4 

3,363 

3 

0,0025 

0,06 

3,880 

4 

3,884 

4 

3,888 

4 

3,892 

4 

3,896 

4 

3,900 

4 

3,go4 

3 

3,907 

4 

3,911 

4 

3,qi5 

4 

o,oo36 

0,07 

4,527 

4 

4,53i 

5 

4.5.36 

4 

4,540 

5 

4,545 

5 

4,55o 

4 

4,554 

5 

4,559 

4 

4,563 

5 

4,568 

4 

0,0049 

0,08 

5,173 

6 

5,179 

5 

5,i84 

5 

5,189 

5 

5,194 

5 

5,199 

6 

5,2o5 

5 

5,310 

5 

5,2i5 

5 

5,230 

5 

0,0064 

0,09 

5,820 

6 

5,826 

6 

5,832 

6 

5,838 

6 

5,844 

5 

5,849 

6 

5,855 

6 

5,861 

6 

5,867 

6 

5,873 

6 

0,008 1 

0,10 

6,467 

6 

6,473 

7 

6,480 

6 

6,486 

7 

6,493 

6 

6,499 

7 

6,5o6 

6 

6,5 1 2 

7 

6,5ig 

6 

6,525 

7 

0,0100 

0,11 

7,ii3 

8 

7,121 

7 

7,128 

7 

7,i35 

7 

7.142 

7 

7.149 

7 

7,1 56 

7 

7,i63 

8 

7. 171 

7 

7,178 

7 

0,013  1 

0,12 

7,760 

8 

7,768 

8 

7,776 

1 

7,783 

8 

7.791 

8 

7.799 

8 

7,807 

8 

7,8i5 

7 

7,822 

8 

7,83o 

8 

0,01 44 

o,i3 

8,407 

8 

8,4 1 5 

9 

8,424 

8 

8,432 

9 

8,441 

8 

8,449 

8 

8,457 

9 

8,466 

8 

8,474 

9 

8,483 

8 

0,0169 

o,i4 

9,o53 

9 

9,062 

ID 

9,072 

9 

9,081 

9 

9,090 

9 

9.099 

9 

g,io8 

9 

9.117 

9 

9.126 

9 

g,i35 

9 

0,01 96 

o,i5 

9,700 

10 

9,710 

9 

9>7i9 

10 

9.729 

10 

9.739 

10 

9.749 

9 

9,758 

10 

9.768 

10 

9,778 

10 

9,788 

9 

0,0225 

0,16 

10,346 

II 

10,357 

10 

10,367 

11 

10,378 

10 

io,388 

11 

10,399 

10 

io,4og 

10 

10,419 

11 

io,43o 

10 

10,440 

10 

o,o256 

0,17 

10,993 

II 

1 1  ,oo4 

II 

11, 01 5 

11 

11,026 

II 

ii,o37 

II 

11,048 

11 

1 1  ,o5g 

12 

1 1 ,07 1 

11 

11,082 

II 

11,093 

11 

0,0389 

0,18 

1 1 ,64o 

II 

ii,65i 

12 

11,663 

12 

11,675 

12 

11,687 

11 

1 1 ,698 

12 

11,710 

12 

11,723 

II 

11,733 

13 

11,745 

12 

o,o334 

0,19 

12,286 

i3 

12,299 

12 

I2,3l  I 

12 

12,323 

i3 

12,336 

12 

12,348 

12 

i2,36o 

i3 

13,373 

13 

12,385 

13 

I3,3g7 

i3 

o,o36i 

0,30 

12,933 

i3 

12,946 

i3 

12,959 

i3 

12,972 

i3 

12,985 

i3 

12,998 

i3 

i3,oii 

i3 

i3,o34 

i3 

i3,o37 

l3 

i3,o5o 

i3 

o,o4oo 

0,21 

13,579 

i4 

13,593 

i4 

1 3,607 

i3 

1 3,620 

i4 

1 3,634 

i4 

I 3, 648 

i3 

i3,66i 

i4 

13,675 

i4 

i3,68g 

i3 

1 3,703 

i4 

0,044 1 

0,22 

14,226 

i4 

i4,24o 

i5 

i4,255 

i4 

14,269 

.4 

14,283 

i5 

14,298 

i4 

i4,3i2 

i4 

14,326 

i4 

1 4,340 

i5 

14,355 

i4 

o,o484 

0,23 

14,872 

i5 

14,887 

i5 

14,902 

i5 

'4,917 

i5 

14,933 

i5 

14,947 

i5 

14,962 

i5 

14,977 

i5 

i4,gg3 

i5 

1 5,007 

i5 

0,0539 

0,24 

i5,5i9 

16 

i5,535 

i5 

i5,55o 

16 

1 5,566 

15 

i5,58i 

16 

15,597 

16 

i5,6i3 

i5 

1 5,638 

16 

1 5,644 

i5 

1 5,659 

16 

0,0576 

0,25 

i6,i65 

17 

16,182 

16 

16,198 

16 

16,214 

17 

i6,23i 

16 

16,247 

16 

16,263 

16 

16,379 

16 

i6,3g5 

17 

1 6,3 1 3 

16 

0,0625 

0,26 

16,812 

17 

16,829 

17 

16,846 

17 

1 6,863 

17 

1 6,S8o 

17 

16,897 

16 

16,913 

17 

16,930 

17 

i6,g47 

17 

1 6,964 

17 

0,0676 

0,27 

■  7,458 

18 

17,476 

17 

17,493 

18 

17,511 

18 

17,539 

17 

17,546 

18 

17,564 

17 

I7,58i 

18 

i7.5gg 

17 

17,616 

18 

0,072g 

0,28 

i8,io5 

18 

18,123 

18 

i8,i4i 

18 

i8,i5q 

19 

18,178 

18 

18,196 

18 

18,214 

18 

l8,232 

18 

i8,25o 

19 

18,369 

18 

0,0784 

0,29 

i8,75i 

19 

18,770 

'9 

18,789 

19 

18,808 

'9 

18,837 

19 

i8,846 

18 

18,864 

'9 

1 8,883 

19 

18,902 

19 

i8,g2i 

19 

o,o84i 

o,3o 

19,397 

20 

i9'4i7 

20 

19,437 

19 

19,456 

20 

19,476 

19 

19,495 

30 

I9,5i5 

'9 

T9,534 

20 

19,554 

19 

19,573 

20 

o,ogoo 

0,3 1 

20,044 

20 

20,064 

20 

20,084 

21 

20,I05 

20 

30,125 

20 

20,145 

3r 

2o,i65 

20 

2o,i85 

20 

20,305 

20 

20,225 

20 

0,0961 

0,32 

20,690 

21 

20,711 

21 

20,732 

21 

20,753 

21 

20,774 

21 

30,795 

30 

30,81 5 

21 

20,836 

21 

30,857 

21 

20,878 

20 

0,1034 

0,33 

21,337 

21 

21,358 

22 

2i,38o 

21 

21,401 

22 

21,423 

21 

31,444 

33 

21,466 

21 

21,487 

31 

2i,5o8 

33 

2i,53o 

21 

0,1089 

0,34 

21,983 

22 

2  2,005 

22 

22,027 

22 

32,049 

23 

22,072 

22 

33,094 

32 

22,116 

22 

22,l38 

33 

22,160 

33 

32,182 

22 

o,ii56 

0,35 

22,629 

23 

22,652 

23 

22,675 

23 

22,698 

22 

23,730 

23 

22,743 

23 

22,766 

23 

22,789 

32 

23,8  I  I 

23 

22,834 

23 

0,1  335 

o,36 

23,275 

24 

23,299 

23 

23,322 

24 

23,346 

23 

23,369 

24 

23,393 

23 

23,4i6 

24 

23,440 

33 

33,463 

23 

23,486 

24 

0,1296 

0,37 

23,922 

24 

23,946 

24 

23,970 

24 

23,994 

24 

24,018 

24 

24,042 

24 

24,066 

24 

24,090 

24 

34.114 

24 

34,i38 

34 

0,1 36g 

o,38 

24,568 

25 

24,593 

25 

24,618 

24 

24,642 

25 

24,667 

25 

24,692 

24 

24,716 

35 

24,741 

25 

24,766 

24 

24,790 

35 

0,1 444 

o,3g 

25,2l4 

26 

25,240 

25 

25,265 

25 

25,290 

26 

25,3i6 

25 

2  5,34 1 

26 

25,367 

25 

35,3g3 

25 

25,417 

35 

25,443 

36 

0,l521 

0,40 

25.860 

26 

25,886 

36 

25,912 

27 

25.939 

26 

25,965 

26 

25,991 

26 

26,017 

26 

26,043 

26 

26,069 

26 

26,095 

25 

0,1600 

0,4 1 

26,506 

27 

26,533 

27 

26,560 

27 

26,587 

26 

36,61 3 

27 

26,640 

27 

26,667 

36 

26,6g3 

27 

26,720 

27 

26,747 

36 

0,1681 

0,42 

27,l52 

28 

27,180 

27 

27,207 

28 

27,235 

37 

27,262 

27 

27,289 

28 

27,317 

37 

27,344 

27 

37,371 

27 

27,3g8 

38 

0,1764 

0,43 

27,799 

28 

27,827 

28 

27,855 

28 

27,883 

28 

27,911 

28 

27,939 

28 

27,967 

38 

27,995 

28 

38,033 

27 

28,o5o 

28 

0,1849 

0,44 

28,445 

28 

28,473 

29 

28,502 

29 

28,531 

28 

28,559 

29 

38,588 

29 

28,617 

38 

28,645 

29 

38,674 

38 

28,703 

29 

0,1936 

0,45 

29,091 

29 

29,120 

29 

29)149 

3o 

29'i79 

29 

29,208 

29 

29,237 

3o 

29,267 

29 

29.296 

29 

39,325 

29 

2g,354 

29 

0,2025 

o,5o 

3i,32o 

33 

32,353 

33 

32,386 

32 

32,4i8 

33 

32,45i 

32 

32,483 

33 

32,5i6 

33 

32,548 

33 

32,58i 

32 

32,6i3 

33 

0,2  5oo 

0,55 

35,549 

36 

35,585 

36 

35,62 1 

36 

35,657 

36 

35,693 

36 

35,729 

35 

35,764 

36 

35,800 

36 

35,836 

36 

35,872 

35 

o,3o25 

0,60 

38,777 

39 

38,8i6 

40 

38,856 

39 

38,895 

39 

38,934 

39 

38,973 

39 

39,012 

39 

3g,o5i 

39 

39,090 

3g 

3g,i3g 

39 

o,36oo 

o,65 

42,004 

43 

42,047 

42 

42,089 

42 

42,i3i 

43 

42,174 

42 

42,216 

43 

42,25g 

43 

42,3oi 

42 

42,343 

42 

42,385 

42 

0,4225 

0,70 

45,230 

46 

45,276 

45 

45,321 

46 

45,367 

46 

45,4i3 

45 

45,458 

46 

45,5o4 

46 

45,55o 

45 

45,5g5 

46 

45,641 

45 

0,4900 

0,75 

48,455 

49 

48,5o4 

49 

48,553 

49 

48,602 

49 

48,65 1 

49 

48,700 

48 

48,748 

49 

48,797 

49 

48,846 

49 

48,8g5 

48 

0,5625 

0,80 

51,678 

52 

5i,73o 

53 

5 1, 783 

52 

5 1, 835 

52 

51,887 

52 

51,939 

53 

5 1  ,gg2 

53 

52,o44 

53 

52,096 

53 

52,i48 

53 

o,64oo 

0,85 

54,900 

56 

54,956 

55 

55,011 

56 

55,067 

56 

55,123 

55 

55,178 

55 

55,233 

56 

55,280 

55 

55344 

55 

55,399 

56 

0,7225 

0,90 

58,121 

59 

58,i8o 

59 

58,239 

59 

58,298 

58 

58,356 

59 

58,4 1 5 

59 

58,474 

58 

58,532 

5g 

58,591 

59 

58,65o 

58 

0,8100 

o,g5 

61,340 

62 

6 1 ,402 

62 

61, 464 

63 

61,527 

62 

61,589 

62 

6i,65i 

62 

6i,7i3 

63 

61,775 

63 

61,83- 

61 

61,898 

62  0,9020  1 

1,00 

64,557 

66 

64,623 

66 

64,689 

65 

64,754 

65 

64,819 

66 

64,885 

65 

64,g5o 

65 

65,oi5 

65 

65,o8o 

66 

65,i46   65|i,oooo| 

12,2513 

12,3008 

12,3505 

12,4002 

12,45 

01 

12,5000 

12,5501 

12,60021 

12,65051 12,70081    c"    I 

■(r  +  r"  y 


•j-  r"^    nejirly. 


646 

647 

648 

65 

65 

65 

129 

129 

i3o 

194 

194 

ig4 

258 

359 

359 

333 

324 

334 

388 

388 

38g 

453 

453 

454 

5l7 

5i8 

5i8 

58r 

582 

583 

64g 

65 
i3o 
195 
2Ô0 
335 
38g 
454 
5ig 
584 


65o 

65i 

652 

653 

65 

65 

65 

65 

T,3o 

i3o 

i3o 

i3i 

iq5 

ig5 

196 

196 

260 

260 

261 

261 

325 

326 

326 

327 

3go 

39. 

3gi 

392 

455 

456 

456 

457 

520 

521 

522 

522 

585 

586 

587 

588 

TABLE 

I. - 

-To  find  the  time  7";  the  sum 

of  the  rail 

ii  )•  -|-  '■  ",  ami  the  choi-d  c  bein 

;  given 

Sum  ot  tlie  lladil  r-\-r  '. 

Prtip.  parts  lor  the  sum  ol"  the  Kodti. 

Choid 

c. 

5,05 

5,06 

UajS   |dir. 

5,07 

5,08    5,09  I  5,10 

I  1  3  1  3|  41  5|  6|  7|8  9 

1 
2 
3 

0  0 
0  0 
0  I 

0 
I 
I 

0 
1 

T  <    - 

I 
I 
2 

1 
3 
2 

2 
3 

Days  |dir. 

Days  |.lir. 

Days  |dil'.   Days  |d 

if.    Days  |dif. 

I 

I 

2 

1 
2 

0,00 

0,000 

0,000 

0,00c 

0.000 

0,000 

0,000 

0,0000 

0,01 

0,653 

I 

o,654 

c 

0,6  54 

I 

o;655 

I  o,656 

0  o,656 

I 

0,000 1 

4 

0  I 

1 

3 

2 

2 

3 

3 

4 

0,02 

i,3oO 

2 

i,3ob 

1 

I,3tH| 

I 

1 .3 1 0 

3   I,3l3 

I  I,3i3 

I 

0,0004 

o,o3 

1,960 

I 

1. 96 1 

2 

1 ,96c 

1:965 

2  1,967 

2  1  ,g6c 

2 

0,0009 

5 

2 

2 

3 

3 

4 

4 

5 

o,o4 

2,6i3 

2 

2,6i5 

3 

3,618 

2 

2 ,620 

3  2,623 

3  2,626 

2 

0,0016 

6 

2 
2 

2 
3 

3 
4 

4 
4 

4 
5 

5 
6 

5 
6 

o,o5 

3,266 

3 

3,261) 

3 

3,273 

4 

3,276 

3  3,279 

3  3,282 

3 

0,0025 

8 

I   2 

2 

3 

4 

5 

6 

6 

7 

OjOti 

3,9 '9 

4 

3.923 

4 

3,927 

4 

3.931 

4  3,935 

3  3,938 

4 

o,oo36 

9 

I   2 

3 

4 

5 

5 

6 

7 

8 

0,07 

4,572 

5 

4,5- 

4 

4,58i 

5 

4^586 

4  4,590 

5  4,5g5 

4 

o,oo4g 

10 

I   2 

3 
3 
4 

4 
4 
5 

5 
6 
6 

6 

8 

o,o« 

5,225 

6 

5,33i 

5 

5,236 

5 

5.241 

5  5,246 

5  5,25i 

5 

0,0064 

7 
8 
8 

9 

OjOy 

5,879 

5 

5,884 

6 

5,890 

C 

5,896 

6  5,go2 

6  5,908 

5 

0,0081 

1 1 

12 

1   2 
I   3 

7 
■7 

9 
10 

10 
II 

0,10 
0,1 1 

6,532 

7>i85 

6 

6,538 
7,192 

7 

6,545 
7,199 

6 

7 

6,55i 
7,206 

7  6,558 
7  7,2i3 

6  6,564 

7  7,220 

6 

n 

0,01 00 
0,01 2 1 

1 3 

i4 

I   3 
I  3 

4 
4 

5 
6 

7 
7 

8 
8 

9 
10 

10 
1 1 

12 
i3 

0,12 

7,83b 

6 

7,846 

b 

7,854 

7 

7.861 

8  7,869 

8  7,877 

7 

0,01 44 

i5 

3   3 

5 

6 

8 

9 
10 

II 

12 

i4 

o,i3 

8,491 

9 

8,5oo 

b 

8,5o8 

8 

8;5i6 

9  8,525 

8  8,533 

8 

0,01 6g 

16 

2  3 

5 

6 

8 

II 

i3 

i4 

P,i4 

9ii44 

9 

9,1 53 

9 

9,162 

9 

9,171 

9  9,180 

9  9,189 

9 

0,0196 

17 
18 

2  3 
2  4 

5 
5 

7 
7 

9 

9 

10 

10 
11 

12 
i3 

i4 
i4 

i5 
16 

o,i5 

9.797 

10 

9,807 

10 

9,817 

9 

9,826 

10  9,836 

10  9,846 

9 

0,0225 

19 

2  4 

6 

8 

II 

i3 

i5 

17 

0,16 

io,45o 

11 

10,461 

10 

10,471 

10 

10,481 

II  10,492 

10  IO,503 

10 

o,o256 

0,17 

11,104 

II 

ii,ii5 

II 

11,126 

10 

ii,i36 

II  Il,l47 

II  ii,i58 

II 

0,0289 

20 

2  4 

6 

8 

10 

12 

i4 

16 

18 

0,18 

11,757 

II 

11,768 

12 

11,780 

12 

11,-92 

11  11 ,8o3 

12  1 1 ,8 1 5 

II 

o,o324 

21 

2  4 

6 

8 

II 

i3 

i5 

17 

19 

0,19 

l2,4lO 

12 

12,422 

12 

12,434 

i3 

12,447 

13  13,459 

12  13,471 

12 

o,o36i 

22 

23 

2  4 
2  5 

7 
7 

9 
9 

II 
12 

i3 
14 

i5 
16 

18 
18 

20 
21 

0,30 

i3,o63 

i3 

13,076 

i3 

13,089 

i3 

l3,102 

12  i3,ii4 

i3  i3,i27 

i3 

o,o4oo 

24 

2  5 

7 

10 

12 

i4 

17 

19 

22 

0,21 

1 3,716 

i3 

13,729 

i4 

1 3,743 

i4 

13,757 

1 3  13,770 

i4  13,784 

i3 

0,044 1 

25 

26 

3  5 
3  5 
3  5 
3  6 

8 
8 
8 
8 

i3 
i3 
i4 
i4 

i5 
i() 
16 

17 

18 
18 

23 
23 

24 

25 

0,22 
0,23 

14,369 
1 5,022 

14 
i5 

1 4,383 
1 5,037 

14 
i5 

14,397 
i5,o52 

i4 
i4 

i4,4i  1 
1 5,066 

i5  14,426 
i5  i5,o8i 

i4  i4,44o 
1 5  i5,oq6 

i4 

i5 

o,o484 
0,0539 

10 
10 

20 
21 

0,24 

15,675 

i5 

15,690 

16 

1 5,706 

i5 

i5,72i 

16  15,737 

1 5  1 5,752 

i6 

0,0576 

27 
28 

1 1 
II 

19 

20 

22 

32 

0,25 

16,328 

16 

16,344 

16 

i6,36o 

16 

16,376 

16  16,392 

17  i6,4og 

16 

0,0625 

29 

3  6 

9 

12 

i5 

17 

20 

23 

26 

0,26 

i6.q8i 

17 

1 6,998 

16 

17,014 

17 

I7,o3l 

17  17,048 

17  17,065 

16 

0,0676 

3o 

3  6 

9 
9 

10 

12 

i5 

18 

21 

24 

27 

0,2- 

1^,634 

I- 

i7,65i 

18 

17,669 

IT 

17,686 

18  17,704 

17  '7,721 

17 

0,0729 

3i 

3  6 

1 2 

16 

19 

19 
20 

22 

25 

28 

0,28 

18,287 

18 

t8,3o5 

18 

18,323 

18 

18,341 

18  18,359 

18  18,377 

iS 

0,0784 

32 

3  6 

i3 

16 

22 

26 

=9 
3o 

0,29 

18.940 

18 

18,958 

19 

18,977 

19 

18,996 

ig  19,015 

18  ig,o33 

19 

0,084 1 

33 

3  7 

10 

i3 

17 

23 

26 

34 

3  7 

10 

i4 

17 

20 

24 

27 

3i 

o,3o 

19,593 

19 

19,612 

19 

19,63 1 

20 

1 9,65 1 

19  19,670 

19  19,68g 

20 

0,0900 

o,3i 

20.245 

20 

20,265 

21 

20,286 

20 

2o,3o6 

20  20,336 

ig  20,345 

20 

0,0961 

35 

4  7 

II 

i4 

18 

21 

25 

28 

32 

0,32 

20,898 

21 

20,919 

21 

20,940 

20 

20,960 

21  20,981 

21  21,002 

20 

0,1024 

36 

4  7 

II 

i4 

18 

22 

25 

29 

32 

0,33 

2i,55i 

22 

21,573 

21 

21,594 

21 

2i,6i5 

21  21,636 

22  21,658 

21 

o,io8g 

37 

4  7 

II 

i5 

19 

33 

26 

3o 

33 

0,34 

22,204 

22 

22,226 

23 

22,248 

22 

22,270 

22  22,292 

22  22,3l4 

22 

0,1 156 

38 
39 

4  8 
4  8 

II 
12 

i5 
16 

19 
20 

33 
23 

27 
27 

3o 
3i 

34 
35 

0,35 

22,857 

22 

22,87g 

23 

22,902 

23 

22,925 

22  22,947 

23  22,970 

22 

0,1225 

o,36 

23,5io 

23 

23,533 

23 

23,556 

23 

23,579 

24  23,6o3 

23  23,626 

23 

0,1296 

4o 

4  8 

12 

16 

20 

24 

28 

32 

36 

0,37 

24,162 

24 

24,186 

24 

24,210 

24 

24,334 

24  24,258 

24  24,282 

34 

o,i36g 

4i 

4  8 

12 

16 

21 

35 

29 

33 

37 

o,38 

24.815 

25 

-:4,84o 

24 

24,864 

25 

24,889 

24  24,Ql3 

25  24,938 

34 

0,1444 

42 

4  8 

i3 

17 

21 

25 

=9 

34 

38 

0,39 

25;468 

25 

25,493 

25 

25,5i8 

25 

25,543 

25  25,568 

26  25,594 

25 

0,l52I 

43 
44 

j     9 
4  9 

i3 
i3 

17 
18 

22 
22 

26 
26 

3o 
3i 

34 
35 

39 

40 

o,4o 

26,120 

26 

26,146 

36 

26,172 

26 

26,198 

26  26,234 

26  26,250 

25 

0,1600 

5  9 
5  9 

5  10 
5  10 

18 
18 
19 

23 
23 

24 
24 

25 

32 
32 

33 
34 
34 

36 

37 
38 
38 
39 

4i 
4i 
42 
43 
44 

0,4 1 

26,773 

27 

26,800 

26 

26,826 

27 

26;853 

26  26.87g 

26  26,905 

27 

0,1681 

45 
46 
47 

i4 
i4 
i4 

27 
28 
28 

0,42 
0,43 

27,426 
28.078 

27 
28 

27,453 
28,106 

27 
28 

27,480 
28,134 

27 
28 

27,507 
28,162 

27  27,534 
27  28,189 

27  27,561 

28  28,217 

27 

38 

0,1764 
0,1849 

0,44 

28,731 

28 

28,759 

29 

28,788 

28 

28,816 

sg  28,845 

28  28,873 

38 

o,ig36 

48 
49 

i4 
i5 

19 
20 

29 
29 

0,45 

29,383 

3o 

29,4i3 

29 

39,442 

29 

29,471 

29  29,500 

2g  29,529 

29 

0,2025 

5o 

5  10 

i5 

20 

25 

3o 

35 

40 

45 

o,5o 

3?,646 

32 

32,678 

32 

32,710 

33 

32,743 

32  32,775 

32  32.807 

33 

o,25oo 

5i 

52 

5  10 

i5 

20 

26 

3i 

36 

4i 

46 

0,55 

35,907 

36 

35,943 

35 

35,978 

36 

36.0I4 

35  36,o49 

36  36,o85 

35 

o,3o25 

J  10 

16 

21 

26 

3i 

36 

42 

47 

0,60 

39,168 

39 

39,207 

38 

39,345 

39 

39,284 

39  39,323 

39  3g,362 

38 

o,36oo 

53 

5  1 1 

16 

21 

27 

32 

37 

42 

48 

0,65 

42,427 

42 

42,469 

43 

43,5l3 

42 

42,554  ^ 

12  42,596  i 

il  42,637 

42 

0,4225 

54 

5  II 

16 

22 

27 

32 

38 

43 

49 

0,70 

45,686 

45 

45,731 

46 

45,777 

45 

45,822  i 

i5  45,867  . 

i5  45,912 

45 

o,4goo 

55  f 

5  II 

17 

22 

28 

33 

39 

44 

5o 

0,75 

48,943 

49 

48,992 

49 

49,041 

48 

49,089  i 

ig  4g,i38  . 

i8  49,186 

48 

0,5625 

56  ( 

3  II 

17 

23 

28 

34 

39 

45 

5o 

0,80 

52,200 

5i 

52,25l 

52 

52,3o3 

52 

52,355 

)2  52,407  , 

ji  52,458 

52 

o,64oo 

57  ( 

)  11 

17 

23 

29 

34 

40 

46 

5i 

o,85 

55,455 

55 

55,5io 

55 

55,565 

55 

55,620  . 

)5  55,675 

J5  55,730 

55 

0,7225 

58  t 

12 

17 

23 

29 

35 

4i 

46 

52 

0,90 

58,708 

58 

58,766 

59 

58,835 

58 

58,883  ' 

)8  58 ,94 1 

39  59,000 

58 

0,8100 

59  c 

12 

18 

34 

3o 

35 

4i 

47 

53 

0,95 

61,960  62 
65,2  11  65 

62,022 

61 

63,o83 

62 

62,145  t 

5i  62,306  t 

)2  62,268 

61 

0,9025 

1,00 

65,276 

64 

65,34o 

65 

65,4o5  ( 

12,903 

55  65,470  ( 

55  65,535 

64  I, 0000 1 

60  ( 

61  t 

62  r 

63  (J 

64  6 

12 
12 

13 

1 3 
i3 

18 
18 
19 
19 

24 
24 
25 
25 
26 

3o 
3i 
3i 

32 

36 
37 
37 
38 
38 

42 
43 
43 

44 
45 

48 

5o 
5o 
5i 

54 
55 
56 
57 
58 

12,7513 

12,8018' 

12,85251 

2  12,954 

1  13,00501  c2  1 

h  .  {r  +  r"y     or  r'^-\-  r"^     nearly.                     | 

652 

653 

654 

655 

656 

657 

19 

32 

— 

— 

— 



— 



65  7 

i3 

20 

26 

33 

39 

46 

52 

59 

I 

65 

65 

65 

66 

66 

66 

I 

66  7 

1 3 

20 

26 

33 

40 

46 

53 

59 

2 

i3o 

i3i 

i3i 

i3i 

i3i 

i3i 

2 

67  7 

i3 

20 

27 

34 

4o 

47 

54 

60 

3 

196 

196 

,96 

197 

197 

197 

3 

68  7 

i4 

20 

27 

34 

4i 

48 

54 

61 

4 

261 

261 

262 

262 

263 

263 

4 

69  7 

i4 

21 

28 

35 

4i 

48 

55 

62 

5 

326 

327 

327 

328 

338 

329 

5 

6 

3qi 

392 

3q2 

393 

394 

394 

6 

70  7 

i4 

21 

28 

35 

42 

49 

56 

63 

7 

456 

457 

458 

459 

459 

460 

7 

80  8 

16 

24 

32 

40 

48 

56 

64 

72 

8 

522 

522 

523 

524 

525 

526 

8 

90  9 

18 

27 

36 

45 

54 

63 

72 

81 
90 

9 

587 

588 

58o 

590 

Sgo 

591 

9 

100  10 

20 

3o 

40 

5o 

60 

70 

80 

TABLE  II. 

—  To  find  the  time  T 

the  sum  of  the  radii 

r  +  r", 

and  the  chord  c 

be 

ng  given. 

Sum  of   the  Radii  r-)-r". 

Cliord 

c. 

5,11 

5,12 

5,13 

5,14 

5,15 

5,16 

5,17 

5,18 

5,19 

5,20 

Days  |dif. 

Days  |dir. 

Days  |dif. 

Days  |dif. 

Days  |dif. 

Days  Idif. 

Days  Idif. 

Days  Idif. 

Days  Idif. 

Days. 

0,00 

0,000 

0,000 

0,000 

0,000 

0,000 

0;000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,657 

I 

0,658 

0 

0,658 

I 

0,659 

I 

0,660 

0 

0,660 

I 

0,661 

I 

0,662 

0 

0,662 

I 

o;663 

0,0001 

0,02 

1,314 

I 

i,3i5 

2 

i,3i7 

I 

I,3l8 

I 

1,319 

2 

1,321 

I 

1,322 

I 

1,323 

1 

1,334 

2 

1,326 

0,0004 

o,o3 

1. 97 1 

2 

1,973 

2 

i>975 

2 

''977 

2 

'.979 

2 

1,981 

2 

1,983 

2 

1,985 

2 

1,987 

I 

1,988 

0,0009 

o,o4 

2,628 

3 

2,63 1 

2 

2,633 

3 

2,636 

2 

2,638 

3 

2,64 1 

3 

2,644 

2 

2,646 

3 

2,649 

2 

2,65  r 

0,0016 

o,o5 

3,285 

3 

3,288 

4 

3,292 

3 

3,295 

3 

3,298 

3 

3,3oi 

3 

3,3o4 

4 

3,3o8 

3 

3,3ii 

3 

3,3i4 

0,0025 

0,06 

3,942 

4 

3,946 

4 

3,950 

4 

3,954 

4 

3,958 

4 

3,962 

3 

3,965 

4 

3,969 

4 

3,973 

4 

3,977 

o,oo36 

0,07 

4,599 

5 

4,604 

4 

4,608 

5 

4,6i3 

4 

4,617 

5 

4,622 

4 

4,626 

5 

4,63 1 

4 

4,635 

5 

4.640 

0,0049 

0,08 

5,256 

5 

5,261 

6 

5,267 

5 

5,272 

5 

5,277 

5 

5,282 

5 

5,287 

5 

5,393 

5 

5,397 

5 

5.302 

0,0064 

0,09 

5,913 

6 

5,919 

6 

5,925 

6 

5,931 

5 

5,936 

6 

5,942 

6 

5,948 

6 

5,954 

5 

5,959 

6 

5^965 

0,0081 

0,10 

6,570 

7 

6,577 

6 

6,583 

7 

6,590 

6 

6,596 

6 

6,602 

7 

6,609 

6 

6,6 1 5 

7 

6,622 

e 

6,638 

0,0100 

0,11 

7,227 

7 

7,234 

8 

7,242 

7 

7,249 

7 

7,256 

7 

7,263 

7 

7,270 

7 

7,277 

7 

7,284 

7 

7,291 

0,0121 

0,12 

7,884 

8 

7,892 

8 

7,900 

8 

7,908 

7 

7,915 

8 

7,923 

8 

7,931 

7 

7,938 

8 

7,q46 

8 

7,954 

0,0 1 44 

0,1 3 

8,541 

9 

8,55o 

8 

8,558 

8 

5,566 

9 

8,575 

8 

8,583 

8 

8.591 

9 

8,600 

8 

8,608 

8 

8,616 

0,0169 

0,1 4 

9)198 

9 

9.207 

9 

9,216 

9 

9,225 

9 

9,234 

9 

9,243 

9 

9,252 

9 

9,261 

9 

9,270 

9 

9,279 

0,0196 

0,1 5 

9,855 

10 

9,865 

10 

9,875 

9 

9,884 

10 

9,894 

10 

9,904 

9 

9,9'3 

10 

9,923 

9 

9,932 

10 

9,942 

0,0225 

o,t6 

IO,5l2 

II 

io,523 

10 

10,533 

10 

10,543 

10 

10,553 

II 

io,564 

10 

10,574 

10 

io,584 

10 

10,594 

II 

io,6o5 

0,03  56 

0,17 

11,169 

II 

11,180 

11 

11,191 

II 

11,202 

II 

1 1,2 1 3 

II 

11,224 

II 

11,235 

II 

11,346 

10 

11,256 

11 

11,267 

0,0289 

0,18 

11,826 

12 

11,838 

II 

11,849 

12 

11,861 

II 

1 1 ,872 

12 

11,884 

12 

1 1 ,896 

11 

11,907 

12 

11,919 

II 

1 1 ,930 

o,o324 

0,19 

12,483 

12 

12,495 

i3 

i2,5o8 

12 

12,520 

12 

12,532 

12 

12,544 

12 

13,556 

12 

13,568 

1 3 

12,58, 

12 

12,593 

o,o36i 

0,20 

i3,i4o 

i3 

i3,i53 

i3 

i3,i66 

i3 

i3,i79 

i3 

13,192 

12 

i3,2o4 

i3 

i3,2i7 

i3 

i3,33o 

i3 

1 3,243 

12 

1 3,255 

o,o4oo 

0,21 

1 3,797 

i4 

i3,8ii 

i3 

13,824 

i4 

1 3,838 

i3 

i3,85i 

i3 

1 3,864 

14 

13,878 

i3 

13,891 

i4 

1 3,905 

i3 

13,918 

0,044 I 

0,22 

14,454 

i4 

i4,468 

i4 

14,482 

i4 

14,496 

i4 

i4,5io 

i5 

i4,535 

14 

14,539 

i4 

14,553 

i4 

14,567 

14 

i4,58i 

0,0484 

0,23 

i5,iii 

i5 

15,126 

i4 

i5,i4o 

i5 

i5,i55 

i5 

15,170 

i5 

i5,i85 

i4 

15,199 

i5 

i5,2i4 

i5 

l5,22g 

14 

1 5,343 

o,o529 

0,24 

15,768 

i5 

1 5,783 

16 

1 5,799 

i5 

i5,8i4 

i5 

15,829 

16 

1 5,845 

i5 

1 5,860 

i5 

15,875 

16 

15,891 

i5 

15,906 

0,0576 

0,25 

16,425 

16 

16,441 

16 

16,457 

16 

16,473 

16 

i6,48q 

16 

i6,5o5 

16 

16,521 

16 

16,537 

16 

16,553 

16 

16,569 

0,0635 

0,26 

17,081 

17 

17,098 

17 

I7,:i5 

17 

I7,i32 

16 

17,148 

17 

i7,i65 

16 

17,181 

'7 

17,198 

17 

I7,2i5 

16 

I7,23r 

0,0676 

0,27 

17,738 

18 

17,756 

17 

17.773 

17 

17.790 

18 

17,808 

17 

17,825 

17 

17.842 

17 

17,859 

18 

17,877 

17 

I7,8q4 

0,0729 

0,28 

18,395 

18 

i8,4i3 

18 

i8,43i 

18 

i8,44y 

18 

18,467 

18 

1 8,485 

18 

i8,5o3 

18 

18,521 

18 

18,539 

17 

1 8, 556 

0,0784 

0,29 

19,052 

19 

19,071 

18 

19,089 

'9 

19,108 

18 

19,126 

19 

19,145 

18 

19,163 

19 

19,182 

'9 

19,201 

18 

'9,219 

0,084 1 

o,3o 

19,709 

19 

19,728 

19 

'9.747 

'9 

19,766 

20 

19,786 

'9 

19,805 

'9 

19.824 

'9 

19.843 

'9 

19,862 

20 

19,882 

0,0900 

0,3 1 

20,365 

20 

20,385 

20 

20,4o5 

20 

20,425 

20 

20,445 

20 

2o,465 

20 

20,485 

20 

2o,5o5 

'9 

20,524 

20 

20,544 

0,0961 

0,32 

21,022 

21 

3 1 ,043 

20 

2 1  ,o63 

21 

21,084 

20 

2i,io4 

21 

21,125 

30 

21,145 

21 

2 1 , 1 66 

20 

21,186 

31 

21,307 

0,1024 

0,33 

21,679 

21 

21,700 

21 

21,721 

21 

21,742 

22 

21,764 

21 

21,785 

21 

21,806 

21 

31,837 

21 

21,848 

31 

21,869 

0,1089 

0,34 

22,336 

21 

22,357 

22 

22,379 

22 

22,401 

22 

22,423 

22 

22,445 

21 

22,466 

23 

3  3,488 

22 

22,510 

33 

22,533 

0,1 156 

0,35 

22,992 

23 

2 3,01 5 

22 

23,o37 

23 

23,060 

22 

23,082 

23 

23,io5 

22 

23,127 

23 

33,149 

23 

23,173 

23 

23,194 

0,1225 

o,36 

2  3,649 

23 

23,672 

23 

23,695 

23 

23,718 

23 

23,74i 

23 

23,764 

23 

23,787 

23 

33,810 

23 

23,833 

23 

23,856 

0,1296 

0,37 

24,3o6 

23 

24,329 

24 

24,353 

24 

24,377 

24 

24,401 

23 

24,424 

24 

24,448 

24 

34,47' 

23 

24,495 

24 

24,519 

0, 1 369 

0,38 

24,962 

25 

24,987 

24 

25,011 

24 

25,o35 

25 

25,060 

24 

25,084 

24 

25,108 

25 

35,i33 

24 

35,i57 

24 

25,181 

û,i444 

0,39 

25,619 

25 

25,644 

25 

25,669 

25 

25,694 

25 

25,719 

25 

2  5,744 

25 

25,769 

25 

25,794 

25 

35,819 

25 

25,844 

0,l52I 

o,4o 

26,275 

26 

26,301 

26 

26,327 

25 

26,352 

26 

26,378 

26 

26,404 

25 

36,429 

36 

26,455 

25 

36,480 

36 

36,506 

0,1600 

0,4 1 

26,932 

26 

26,958 

27 

26,985 

26 

27,011 

26 

27,037 

26 

27,063 

27 

37,090 

26 

27,116 

36 

27,142 

26 

27,168 

0,1681 

0,42 

27;588 

27 

27,61 5 

27 

27,642 

27 

27,66g 

27 

27,696 

27 

27,723 

27 

27,750 

27 

27,777 

27 

27,804 

26 

27,83o 

0,1764 

0,43 

28,245 

27 

28,272 

28 

28,300 

28 

28,328 

27 

28,355 

28 

28,383 

27 

38,410 

28 

28,438 

27 

28,465 

28 

28,493 

0,1849 

0,44 

28,901 

29 

28,930 

28 

28,958 

28 

28,986 

28 

29,014 

28 

29,042 

29 

29,071 

38 

29,099 

28 

39,137 

28 

29,155 

0,1936 

0,45 

29,558 

29 

29,587 

29 

29,616 

28 

29,644 

29 

29,673 

29 

29,702 

29 

29,731 

29 

29.760 

28 

29,788 

29 

29,817 

0,2025 

o,5o 

32,839 

33 

32,872 

32 

32,904 

32 

32,936 

32 

32,968 

32 

33,000 

32 

33,o32 

33 

33,n64 

32 

33,096 

32 

33,128 

o,25oo 

0,55 

36,120 

36 

36,i56 

35 

36,191 

35 

36,226 

36 

36,262 

35 

36,297 

35 

36,332 

35 

36,367 

35 

36,4o3 

36 

36,438 

o,3o25 

0,60 

39,400 

39 

39,439 

39 

39,478 

38 

39,516 

39 

39,555 

38 

39,593 

38 

39,63 1 

39 

39,670 

38 

39,708 

39 

39,747 

o,36oo 

o,65 

42,679 

42 

42,721 

42 

42,763 

42 

42,8o5 

42 

42,847 

4i 

42,888 

42 

42,930 

41 

43,971 

42 

43.013 

42 

43,055 

0,4225 

0,70 

45,957 

45 

46,002 

46 

46,048 

45 

46,093 

45 

46,i38 

44 

46,182 

45 

46,227 

45 

46,272 

45 

46,3 1 7 

45 

46,362 

0,4900 

0,75 

49,234 

49 

49,283 

48 

49,33i 

48 

49,379 

48 

49,427 

48 

49,475 

49 

49,524 

48 

49,572 

48 

49,620 

48 

49,668 

0,5625 

0,80 

52,5io 

52 

52,562 

5i 

52,6i3 

52 

52,665 

5i 

52,716 

5i 

53,767 

52 

52,819 

5i 

52,87c 

5i 

52,921 

5i 

52,972 

0,6400 

o,85 

55,785 

54 

55,839 

55 

55,894 

55 

55,949 

54 

56,oo3 

55 

56,û58 

55 

56,1 13 

54 

56,167 

55 

56,222 

54 

56.376 

0,7225 

0,90 

59,o58 

58 

59,116 

58 

59,174 

58 

59,232 

58 

59,290 

57 

59,347 

58 

59,405 

58 

59,463 

58 

59,521 

57 

59',578 

0,8100 

0,95 

62,329 

62 

62,391 

61 

62,452 

61 

62,5i3 

61 

62,574 

61 

62,635 

61 

62.696 

61 

62,757 

61 

62,818 

61 

62,879 

0,9025 

1,00 

65,599 

65 

65,664 

64 

65,728 

65 

65,7931  64 

65,857 

65165,92^ 

64 

65,9861  64 

66,o5o 

6/ 

66,1 14 

64 

66,178 

1 ,0000 

13,0561 

13,1072 

13,1585 

1 13,2098 

13,2613113,3128 

13,3645 

13,4162 

13,4681 

13,5200 

^2 

h  ■('■  +  '■")'     or     r'  +  r"=     nearly.                                                                                                 | 

656 

657 

658 

659 

660 

661 

662 

663 

I 

6G 

66 

66 

66 

66 

66 

66 

66 

I 

2 

i3, 

i3i 

l32 

l32 

l32 

l32 

l32 

i33 

2 

3 

'97 

'97 

197 

198 

198 

198 

199 

199 

3 

4 

262 

263 

263 

264 

264 

264 

265 

265 

4 

5 

328 

Sag 

329 

33o 

33o 

33i 

33 1 

332 

5 

6 

394 

394 

395 

395 

396 

397 

397 

398 

6 

7 

459 

460 

461 

461 

462 

463 

463 

464 

7 

8 

525 

526 

526 

527 

528 

52q 

53o 

53o 

8 

9 

59 

0 

'9' 

592  1 

593 

5Ç 

)4  1 

595 

5( 

36 

597 

9 

TA  RLE 

II 

—  To  find  the  time  T 

,  the  sum  of  tlic  v; 

dii 

^■Vr", 

and 

the  chord 

c  being  given. 

Sum  of  the  Radii  r-f-r".                                                                                                                1 

Chord 

c. 

5,->0 

5,30 

5,40 

5,50 

5,60 

5,70 

5,80 

5,90 

6,00 

6,10 

Days  |dir. 

Huy*.  |dir. 

Days  |dir. 

Days  |dir. 

Dnysldil'. 

Days  lilif. 

Days|,lir. 

Day»  Idif. 

Days  |dil. 

Days  Idir. 

0,00 

0,0(K) 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,000 

0,0000 

0,01 

o,fi63 

6 

0,669 

6 

0,675 

7 

0,682 

6 

o,68S 

6 

0,694 

6 

0,700 

6 

0,706 

6 

0,713 

6 

0,718 

6 

0,0001 

0.02 

1.326 

13 

1,338 

i3 

I,35l 

12 

1,363 

i3 

1,376 

12 

1,388 

13 

1 ,4ot. 

12 

I  .4 1  2 

12 

1,434 

13 

1,436 

II 

o,ooo4 

o,o3 

i.il88 

'9 

2,007 

HI 

3,03.6 

19 

2,045 

.8 

2, 06  3 

'9 

2,082 

18 

2 , 1 00 

18 

2.118 

18 

2,1 36 

18 

2,i54 

17 

o,ooog 

0,04 

3,()5l 

26 

2,677 

25 

3,702 

35 

2,727 

24 

2,75i 

25 

2,776 

24 

2,800 

24 

2,834 

24 

2,848 

24 

2,872 

23 

0,0016 

o,o5 

3,3i4 

32 

3,346 

3i 

3,377 

3i 

3,4o8 

3i 

3,43g 

3i 

3,470 

3o 

3,5oo 

3o 

3,53o 

3o 

3,56o 

29 

3,58g 

3o 

0,0026 

0,1)6 

3,977 

38 

4,01 5 

38 

4,o53 

37 

4,ogo 

37 

4,^27 

37 

4,164 

36 

4,300 

36 

4,236 

36 

4,272 

35 

4,3o7 

35 

o,oo36 

0,07 

4.64" 

44 

4,684 

44 

4,738 

44 

4.772 

43 

4,8  ■  5 

43 

4,858 

42 

4,goo 

42 

4.943 

43 

4,984 

4i 

5,025 

4i 

o,oo4g 

0,08 

5;3o2 

5i 

5,353 

5o 

5,4o3 

5o 

5,453 

DO 

5,5o3 

49 

5,552 

48 

5,600 

48 

5,648 

48 

5,696 

47 

5,743 

47 

0,0064 

0,09 

5,965 

57 

6,022 

57 

6,079 

56 

6,1 35 

55 

6,190 

55 

6,245 

55 

6,3oo 

.54 

6,354 

54 

6,408 

53 

6,461 

53 

0,0081 

0,10 

6,628 

63 

6,691 

63 

6,754 

63 

6.817 

61 

6,878 

61 

6,939 

61 

7,000 

60 

7,060 

60 

7,130 

59 

7,179 

58 

0,0i00 

0,11 

7,'9' 

70 

7,36i 

69 

7,43o 

68 

7,498 

68 

7,566 

67 

7,633 

67 

7,700 

66 

7,766 

66 

7,833 

65 

7,897 

64 

0,0121 

0,I5 

7.ii54 

76 

8,o3o 

75 

8,io5 

75 

8,180 

74 

8,254 

73 

8,327 

73 

8,400 

72 

8,472 

T- 

8,544 

70 

8,6i4 

71 

0,01 44 

o,i3 

8,616 

83 

8,699 

81 

8,780 

81 

8,861 

81 

8,g42 

79 

9,021 

79 

g,ioo 

78 

9.178 

7- 

9,255 

77 

9,332 

76 

o.oifig 

o,i4 

9>279 

89 

9,368 

88 

9.456 

87 

9,543 

86 

9,629 

86 

9,7 15 

85 

g,8oo 

84 

9,884 

83 

9,967 

83 

io,o5o 

82 

0,0196 

o,i5 

9.945 

95 

TO,o37 

94 

io,i3i 

94 

10,225 

92 

10,317 

92 

io,4og 

91 

io,5oo 

90 

10,590 

89 

10,67g 

89 

10,768 

88 

0,0325 

0,16 

io,6o5 

101 

10,706 

101 

10,807 

99 

10,906 

99 

1 1  ,oo5 

98 

ii,io3 

97 

I  l,300 

96 

11,396 

95 

■  i,3gi 

95 

11,486 

94 

o,0356 

0,17 

11,267 

108 

11,375 

107 

11,482 

106 

1 1 ,588 

io5 

1 1 ,693 

104 

■1,797 

io3 

1 1  ,goo 

103 

12,002 

101 

12,lo3 

101 

I2,204 

0,028g 

0,18 

1 1 ,930 

114 

12,044 

ii3 

i2,i57 

112 

12,269 

1 1 1 

i3,38o 

II I 

■  2,491 

loq 

12,600 

108 

12,708 

107 

i2,8i5 

106 

12,921 

10Ê 

o,o324 

o,ig 

12,593 

120 

I2,7i3 

120 

12,833 

118 

■  2,951 

117 

1 3,068 

116 

i3,i84 

116 

i3,3oo 

114 

■  3,4i4 

ii3 

■  3,527 

113 

■  3,639 

112 

o,o36i 

0,20 

i3,355 

127 

i3,382 

126 

i3,5o8 

125 

i3,633 

123 

1 3,756 

122 

13,878 

131 

■3,999 

121 

l4,^30 

■'9 

■4,23g 

116 

■  4,357 

117 

o,o4oo 

0,3 1 

i3,c|i8 

i33 

i4,o5i 

I  32 

i4,i83 

i3i 

■4,3i4 

i3o 

■  4,444 

128 

■4,572 

127 

■4,69g 

■27 

14.836 

135 

i4,g5i 

124 

■  5,075 

123 

0,044 1 

0,23 

i4,58i 

139 

14,720 

■39 

14,859 

■37 

■4,996 

i35 

i5,i3i 

i35 

■  5,266 

i33 

■5,399 

l33 

i5;53i 

l33 

1 5,663 

i3o 

15,793 

■29 

0,0484 

0,23 

i5,243 

1 46 

1 5,389 

145 

1 5,534 

i43 

■  5,677 

■  42 

15,819 

■  4^ 

1 5, 960 

i3g 

16,099 

i38 

16,337 

■  37 

16,374 

i36 

i6,5io 

i35 

0,0529 

0,24 

15,906 

l52 

i6,o58 

i5i 

16,209 

i5o 

16,359 

i48 

16,507 

146 

1 6,653 

1 46 

■6,799 

144 

16,943 

143 

17,086 

142 

17,228 

lAi 

0,0576 

0,25 

16,569 

1 58 

16,727 

■57 

16,884 

1 56 

1 7,o4o 

■  54 

17,194 

1 53 

'7,347 

l53 

■7,49g 

i5o 

17,649 

l4g 

■7,798 

148 

17,946 

1 46 

0,0625 

0,26 

I7,23i 

i65 

17,396 

164 

17,560 

162 

■  7,722 

160 

17,883 

■  59 

i8,o4^ 

■  58 

■8,199 

i56 

18,355 

1 55 

i8,5io 

i54 

18,664 

I  52 

0,0676 

0,27 

17,894 

171 

i8,o65 

170 

18,335 

168 

i8,4o3 

167 

18,570 

.65 

■8,735 

i63 

i8,8gb 

i63 

19,061 

161 

iq,222 

■  59 

ig,38i 

■  58 

0,072g 

0,28 

18, 556 

178 

18,734 

176 

i8,gio 

174 

19,084 

173 

19,257 

■72 

19,429 

169 

19,598 

■69 

19,767 

166 

19,933 

166 

20,099 

■  64 

0,0784 

0,29 

■9.2'9 

i84 

19,403 

183 

ig,5S5 

iSi 

19,766 

■  79 

19,945 

177 

20,122 

176 

20,298 

■74 

20,472 

173 

20,645 

■72 

30,817 

170 

0,0841 

o,3o 

19,882 

190 

20,072 

189 

20,261 

186 

20,447 

i85 

20,632 

184 

30,816 

182 

20,998 

180 

21,178 

179 

21,357 

■77 

21,534 

176 

o,ogoo 

0,3 1 

20,544 

197 

20,74l 

■95 

2o,g36 

193 

21,12g 

■9' 

21,330 

190 

2 1,5 10 

188 

2i,6g8 

186 

31,884 

i85 

2  2  ,069 

i83 

22,252 

182 

o,og6i 

0,32 

21,20^ 

2o3 

21,410 

201 

2 1 ,6 1 1 

■99 

2I,8lO 

198 

22,008 

195 

22,2o3 

194 

22,397 

'93 

33,590 

.190 

22,780 

190 

2  2,g70 

187 

0,1024 

0,33 

21,869 

210 

22,079 

207 

22,386 

2o5 

22,491 

2o4 

22,695 

202 

22,897 

200 

23,097 

198 

23,2g5 

197 

23,493 

195 

23,687 

ig4 

0,1  o8g 

0,34 

22,532 

2l5 

22,747 

214 

22,961 

212 

23,173 

210 

23,383 

208 

23,591 

206 

23,797 

204 

24,001 

203 

24,204 

301 

24,4o5 

'99 

0,1 1 56 

0,35 

23,194 

223 

23,4i6 

220 

23,636 

218 

23,854 

216 

24,070 

314 

24,284 

3l3 

24,497 

310 

24,707 

209 

24,916 

206 

35,122 

206 

0,1225 

o,36 

23,856 

339 

24,o85 

226 

24,3 1 1 

224 

24,535 

223 

24,758 

220 

24,978 

3l8 

35,196 

217 

35,4i3 

214 

25,627 

3l3 

2  5,84o 

211 

0,1 296 

0,37 

24,519 

2  35 

24,754 

232 

24,986 

33  1 

25,217 

223 

25,445 

226 

25,671 

335 

25,896 

222 

26,118 

221 

26,339 

319 

26,558 

216 

0,1369 

o,38 

25,r8i 

241 

25,422 

239 

25,661 

237 

25,898 

235 

26,133 

232 

26,365 

33o 

36,5g5 

229 

36,834 

226 

37,o5o 

225 

27,275 

323 

0,1 444 

0,39 

25,844 

247 

2'5,og  1 

245 

26,336 

243 

26,57g 

241 

26,820 

239 

27,o5g 

236 

27,295 

235 

27,530 

232 

27,762 

33l 

27,993 

228 

0,1 521 

o,4u 

26,506 

254 

26,760 

25l 

27,011 

249 

37,360 

247 

27,507 

245 

27,752 

243 

27,995 

34o 

28,235 

2  3g 

28,474 

336 

28,710 

235 

0,1600 

0,4 1 

27,168 

260 

27,428 

258 

27,686 

256 

27,942 

353 

28,195 

25l 

28,446 

248 

28,694 

247 

28,941 

244 

29,185 

343 

29,428 

240 

0,1681 

0,42 

37,83o 

267 

28,097 

264 

38,36i 

262 

28,623 

25g 

28,883 

257 

2g,i3g 

355 

39,394 

353 

29,646 

25l 

'9.897 

248 

3o,i45 

246 

0,1764 

0,43 

28,493 

273 

28,^66 

270 

29,o36 

368 

2g,3o4 

265 

29,569 

264 

3g,833 

360 

3o,og3 

2  5g 

3o,352 

356 

3o,6o8 

355 

3o,863 

252 

0,1849 

0,44 

29,155 

279 

29,434 

277 

29,711 

274 

29,985 

372 

3o,257 

269 

30,526 

367 

30,793 

264 

3 1, 057 

363 

3 1, 320 

260 

3i,58o 

258 

o,ig36 

0,4a 

39,817 

286 

3o,io3 

283 

3o,386 

280 

3o,666 

378 

3o,g44 

275 

3i,2ig 

273 

31,492 

371 

3 1, 763 

268 

32,o3i 

266 

32,2g7 

264 

0,2025 

o,5o 

33,138 

3i7 

33,445 

3i5 

33,760 

3ii 

34,071 

3og 

34,38o 

3o6 

34,686 

3o3 

34,98g 

3oi 

35,390 

298 

35,588 

296 

35,884 

293 

o,25oo 

0,55 

36,438 

349 

36,787 

346 

37,i33 

343 

37,476 

33g 

37,81 5 

337 

38,i52 

334 

38,486 

33 1 

38,8i7 

3Ï8 

39.145 

325 

3g,470 

323 

o,3o25 

0,60 

39.747 

38 1 

40,128 

377 

4o,5o5 

374 

40,879 

371 

4i,25o 

367 

4i,6i7 

365 

4i,g82 

36 1 

43,343 

358 

42.701 

355 

43,o56 

352 

o,36oo 

o,65 

43.n55 

4i3 

43.468 

409 

43,877 

4o5 

44,282 

4o2 

44,684 

398 

45,082 

3g5 

45,477 

3gi 

45,868 

388 

46,256 

384 

46,640 

383 

0,4225 

0,70 

46,363 

445 

46,807 

440 

47,247 

437 

47,684 

433 

48,117 

42g 

48,546 

425 

48,g7i 

43. 

49,393 

4i8 

4g,8io 

4i4 

5o,224 

4ii 

o,4goo 

0,75 

40,668 

476 

5o,[44 

473 

5o,6i7 

468 

5r,o85 

464 

5i,54g 

459 

52,008 

456 

52,464 

45  ■ 

52.9,5 

448 

53,363 

AU 

53,807 

440 

0,5625 

0,80 

52,972 

5ou 

53,481 

5o4 

53,g85 

5oo 

54,485 

495 

54,g8o 

4go 

55,470 

486 

55,g56 

482 

56,438 

478 

56,gi6 

Ali 

57,38g 

470 

o,64oo 

o,85 

56,276 

54. 

56,817 

536 

57,353 

53o 

57,883 

526 

58,4o9 

521 

58,93o 

5^7 

59,447 

5l2 

59,959 

5o8 

60,467 

5o3 

6o,g70 

5oo 

0,7225 

0,90 

59.578 

573 

6o,i5i 

568 

60,71g 

563 

61.281 

557 

6 1,838 

552 

62.390 

547 

62,937 

542 

63,479 

538 

64,017 

534 

64,55 1 

538 

0,8100 

0,95 

62,879 

6o5 

63,484 

599 

64,o83 

594 

64,677 

588 

65,365 

583 

65;848 

578 

66,436 

573 

66,999 

567 

67,566 

564 

68,i3o 

558 

o,go25 

1,00 

66,178 

637 

66,8 1 5 

632 

67,447 

625 

68,073 

619 

68,6gi 

6i4 

69,305 

608 

69,913 

6o4 

70,517 

597 

71,114 

593 

71,707 

588 

1 ,0000 

13,5200 

14,0450 

14,5â00 

15,1250 

15,6800 

16,2450 

16,8200 

17,4050 

18,0000 

18,6050 

â 

1                                                                                                     5  .  (r  -)-  r")-     or    r^  -|-  r  "^    nearly.                                                                                                      | 

662 

665 

668 

671 

674 

677 

680 

683 

686 

689 

692 

6g5 

698 

701 

704 

707 

710 

7i3 

7^6 

71g 

66 

67 

67 

67 

67 

68 

68 

68 

69 

69 

6q 

70 

70 

70 

70 

?■ 

71 

1' 

72 

72 

l32 

i33 

1 34 

1 34 

i35 

1 35 

1 36 

1 37 

■37 

1 38 

1 38 

i3g 

i4o 

i4o 

i4i 

i4^ 

143 

143 

143 

1 44 

199 

200 

200 

201 

202 

203 

204 

205 

206 

207 

208 

2oq 

2og 

210 

211 

312 

3l3 

214 

2l5 

216 

265 

266 

267 

268 

270 

271 

272 

273 

374 

276 

277 

278 

279 

280 

282 

283 

284 

285 

386 

288 

33i 

333 

334 

336 

337 

33q 

340 

342 

343 

345 

346 

348 

34q 

35 1 

352 

354 

355 

357 

358 

36o 

397 

399 

4oi 

4o3 

4o4 

406 

408 

4io 

4l2 

4i3 

4i5 

417 

419 

421 

422 

424 

426 

428 

43o 

43 1 

463 

466 

468 

470 

472 

474 

476 

478 

480 

482 

484 

487 

48q 

4qi 

4q3 

4q5 

497 

499 

5oi 

5o3 

53o 

532 

534 

537 

53q 

542 

544 

546 

549 

55i 

554 

556 

558 

56i 

563 

566 

568 

570 

573 

575 

596 

599 

601 

604 

607 

609 

612 

6i5 

6,7 

620 

623 

626 

628 

63 1 

634 

636 

639 

642 

644 

647 

il9 


TABLE  II.  —  To  find  the  time  T";  the  sum  of  the  radii  r-\-r",  and  the  chord  c  being  given. 


Sum  of  the  Radii  r-\-r' 


Chord 

c. 


OjOO 

0,0 1 
0,02 
o,o3 
0,04 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
0,1 3 
o,i4 

0,1 5 
0,16 
0,17 
0,18 
0,19 

0,20 
0,21 
0,22 

0,23 

0,24 

0,25 
0,26 

0,27 
0,28 
0,29 

o,3o 
0,3 1 
0,32 
0,33 
0,34 

0,35 
0,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
o,5o 
0,55 
0,60 
o,65 
0,70 

0,75 
0,80 
0,85 
0,90 
0,95 
r,oo 


6,20 


Days  |ilif. 


O,0CO 
0,724 


3,619 

2q 

4,343 

35 

5,066 

4> 

5,790 

46 

b,5i4 

52 

7.237 

58 

7,961 

64 

8,685 

70 

Q,4o8 

76 

IO,l32 

82 

io,856 
ii,58o 
i2,3o3 
1 3,037 
i3,75i 

14,474 
15,198 
15,932 
16,645 
17,369 

18,093 
18,816 
19,539 
20,263 

20,987 

21,710 
22,434 
23,i57 
23,881 
24,604 

25,328 
26,05 1 
26,774 
37,498 
28,221 

28,945 
29,668 
30,391 
3i,ii5 
3 1,838 

33,56i 
36,177 
39,793 
43,408 
47,022 
5o,635 

54,247 
57,859 
61,470 
65,079 
68,688 
73,295 


116 

132 
127 
1 34 
139 

146 

i5i 
157 
i63 
168 

175 
180 
186 
193 
198 

2o3 

209 

316 

221 
227 

233 
238 
245 

25o 
256 

262 
29 

320 

349 
378 
408 

437 

466 
495 
525 
554 
584 


19,2200 


6,30 


Days  lilif. 


0,000 
0,730 
1,459 
2,i8y 
3,918 

3,648 

4,377 
5,107 
5,836 
6,566 

7,295 
8,035 
8,755 
9,484 

JO,2l4 

10,943 
I  1,673 
12,402 

i3,i33 
i3,86i 

14,590 
1 5,320 
16,049 

16,779 
i7,5oS 

i8,238 
18,967 
19,696 
20,426 
2i,i55 

21,885 

23,6t4 

23,343 

24,073 
24,803 

25,53i 
26,260 
26,990 
37,719 
28,448 

29,177 
39.906 
3o,636 
3 1, 365 
32,094 

33,823 
36,468 
4o.ii3 
43,757 
47,400 
5 1,043 

54,684 
58,335 
61,965 
65, 604 
69,343 
72,879 


5 

13 

1 

33 

29 

35 
4( 

4- 

53 

58 
63 

eg 

75 
80 

87 
93 
98 

io3 
no 

116 
121 
127 
i33 
139 

i44 
i5o 
1 56 
161 
168 

173 
179 
i85 

1  go 
196 

302 

208 

2l3 

219 

225 

23l 

237 
243 
2 

2  54 

260 
289 
3i7 
346 
375 
4o4 

434 
462 
491 

520 

549 

578 


19,8450 


6,40 


Days  |dif. 


0,000 
0,735 
1,471 
2,206 
3,941 

3,677 

4,4 1 3 
5, 1 47 
5,883 
6,618 

7,353 
8,0! 
8,824 
9,559 
io,3g4 

1  i,o3( 
1 1 ,765 
i3,5oc. 
i3,235 
i3,97i 

14,706 
1 5,441 
16,176 
16,912 
17,647 

18,382 
19,117 
1 9,852 
20,587 

21,323 
22,o58 

22,793 

33,528 
24,263 
34,gg8 

25,733 
36,468 
27,203 
27,938 
28,673 

29, 408 
3o,i43 
30,878 
3i,6i3 
32,348 

33,o83 
36,757 
4o,43o 
44, io3 

47,775 
5 1, 447 

55,118 
58,787 
63,456 
66,124 
69,791 
73,437 


23 

38 

34 
40 
45 

5i 

57 
63 
68 
74 
80 

8 

9 

97 
io3 
108 

114 
120 
126 
1 3 
1 3 

i43 

149 
1 55 
161 
166 

171 
177 
i83 
189 
195 

200 
206 

212 
218 
223 

229 

235 
240 

346 

252 

257 
286 

3i5 
344 
373 


2q 
459 
488 

5i7 

545 
574 


20,4800 


6,50 


Days  111  if. 


0,000 
0,741 
T,482 
2,223 
2,964 

3,7o5 
4.446 
5,187 
5,928 
6,66g 

7,4io 
8,i5i 
8,892 
9,633 
10,37. 

11,11 5 
11,856 
12,597 
1 3,338 
14,079 

i4,83o 
i5,56i 
i6,3o3 
17,043 
17,784 

18,535 
19,266 
20,007 
3o,748 
21,489 

22,229 
22,970 
23,711 
24,453 
25,193 

25,933 
26,674 
37,4 1 5 
28,1 56 


39,637 
30,378 
3i,ii8 
3i,85g 
33,600 

33,340 

37,043 

40.745 

44,44 

4S,i48 

5 1, 848 

55,547 
59,246 
62.944 
66,64 1 
70,336 
74,o3i 


86 

g 

g7 

io3 
108 

114 
120 

125 

i3i 
1 36 

143 
1 48 
1 53 
i5q 
164 

171 
176 
182 
187 
193 

199 

205 
210 
216 
22i 


333 

23g 
344 

2  5o 

2  56 
284 
3i3 
341 
369 
398 

43 

455 

484 

5l2 

541 
570 


21,1250 


6,60 


Days  |dif. 


0,000 
0,747 
1,493 
2,240 
2,987 

3,734 
4,480 
5,337 
5,974 
6,720 

7,467 

8,2i4 

8,961 

9,707 

10,454 

11,201 
11-947 
12,694 
i3,44i 
14,187 


14,934 
1 5,681 
16,427  124 
17,174  129 
17,920  i36 


17 
22 

28 
S4 
40 
45 
5i 

57 
63 

67 
74 
79 

84 
90 
96 
101 
107 


18,667 
19,414 
20,160 
20,90- 
31,653 

22,400 
23,i46 
23,893 
24,639 
25,386 

26,132 
26,879 
27,625 
28,372 
29,118 

29,864 
3o,6i  I 
3 1, 357 
32,10.3 
32,85û 

33,596 
37,327 
4i,o58 

44,7 

48,5i7 

52,246 

55,974 
59,701 
63,428 
67,153 

70,877 
74,601 


1 46 

l52 

i58 
164 

169 
175 
180 
186 
191 

1 98 
2o3 

209 

21 
220 

226 
23l 
237 
243 


254 

282 

3io 

338 

36 

395 

423 
452 
48o 
5o8 
537 
565 


21,7800 


6,70 


Days  Idif. 


0,000 
0,752 
I,5o5 
3,357 
3,009 

3,762 

4,5 1 4 
5,267 

6,019 
6,771 

7,534 
8,376 

9,028 

9,781 
10,533 

11,385 
12,037 
1 2 ,790 
1 3,542 
14,294 

i5,o47 
1 5,799 
i6,55i 
i7,3o3 
i8,o56 

18,808 
19,560 

20,3t2 

2i,o65 


22,569 

23,321 

24,073 

34,835 

25,577 

26,330 
27,082 
27.834 
28,586 
29,338 

30,090 
3o,842 
31,594 
32,346 
33,098 

33,85o 
37,609 
4 1, 368 
45,126 
48,884 
52,64i 

56,397 
6o,î53 
63, 008 
67,661 
7i>4i4 
75,166 


1 46 
i5i 
[56 
162 

168 
174 
179 
i85 

191 

195 
201 
207 
212 
218 

224 
329 
235 
240 
246 

252 
280 
3o8 
336 
364 
393 

431 

448 
476 
5o5 
533 
56i 


22,4450 


6,80 


Days  Id  if. 


0,000 
o,758 
i,5i6 
2,274 
3,o32 

3,790 
4,548 
5,3o6 
6,064 
6,822 

7,579 
8,33 
9,095 
9,853 
10,61 1 

11,369 
12.137 
i2;885 
1 3,643 
i4,4oi 

i5,i59 

15,916 

16,67 

17,433 

18,190 

18,948 
19,706 
20,463 
21,221 
21,979 

22,737 
23,495 

24-,253 
25,010 
25,768 

26,535 
27,283 
28,041 
28,798 
29,556 

3o,3i4 
3 1 ,07 1 
3i,82q 
32,586 
33,344 

34,102 

37  „ 
41,676 
45,463 
49,248 
53,o33 

56,8 1 8 
60,601 
64,384 
68,166 

71,947 
75,737 


28 
33 

3g 

44 
5o 

56 
61 

67 

72 
78 

83 
89 
94 
100 
io5 

III 

117 
122 

12( 

1 33 

1 39 
1 44 
i5o 
i56 
161 

166 
173 
178 
i83 
[89 

195 

200 

2o5 

212 
21- 


333 
238 
333 
339 

245 
25o 

278 

3o6 
334 
362 
389 

417 
445 
473 
5oi 
529 
557 


23,1200 


6,90 


Days  [dif. 


0,000 
0,764 
1,527 
2,291 
3,o54 

3,818 
4,58 1 
5,345 
6 
6,872 

7,635 
8,3y8 
9,163 
9,925 
10,1'" 

11,453 

I3,3l6 
12,979 

i3,743 
i4,5o6 

15,270 
i6,o33 
16,796 
17,560 
18,323 

19,087 
i9,85o 
20,61 3 
21,377 

22,l4o 

22,903 
23,667 

24,43o 
25,ig3 
25,95 

26,721 
27,483 
28,246 
29,0  n 
39,773 

3o,536 
31,399 
33,062 
32.825 
33,589 

34,352 
38,167 
41,982 
45,796 
49,610 
53,422 

57,235 
61,046 
64.857 
68,667 
72,476 
76,284 


27 
33 
38 
44 

4g 

55 
61 
66 

72 

77 

83 
88 
94 
99 
io5 

no 
116 
122 
137 
1 33 

l37 
1 43 
i4g 
i54 
160 

166 
171 
176 
183 
187 

193 
199 

3o4 
209 
2l5 

221 
226 
232 
2  38 
242 

248 

■6 
3o3 
33i 
358 
387 

4i4 
442 
469 
497 
"25 
552 


23,8050 


7,00 


Days  |dif. 


0,76c 

i,53b 

2,3o' 

3,076 

3,845 
4,6 1 4 
5,383 
6,i52 
6,921 

7,690 
8,459 
9,338 
9,997 
10,766 

11,535 
1 2 ,3o4 
13,073 
1 3,842 
1 4,61 1 

i5,38o 
16,149 
1 6.9 1 8 

17^687 
1 8,456 

19,224 
19-993 
20,762 
2 1, 53 1 
22,3oo 

23,069 
23,838 
24,606 
25,375 
26,144 

26,913 
27,682 
28,450 
29,219 
39,988 

30,757 
3i,535 
33,2g4 
33,o63 
33,83 1 

34,600 
38,443 
42,285 
46,127 
49,968 
53,809 


93 
98 
io4 

109 
ii5 
120 
126 
i3i 

1 37 
143 
1 48 
1 53 
i5g 

164 
169 
176 
181 
186 

191 

ig7 

2o3 

208 

2l3 

219 

225 
23o 

235 
241 

246 

274 
3oi 
329 
356 
383 


57,649411 
61,488439 
65,326466 
69,164494 
73,001  521 
76,8361549 


24,5000 


7,10 


Days  [dif. 


0,000 
0,774 
,.549 

2.323 

3,098 
3.872 

4,647 
5,421 
6,196 
6,970 

7,745 
8,519 
9,294 
10,068 
10,843 

11,617 
12,393 
1 3, 166 
1 3,940 
14,71 5 

i5,4  _ 
16,364 
i7,o38 
I7,8i3 
18,587 

ig,36i 
20,1 36 

30,gT0 

21,684 
22,45g 

23,233 
24,007 
24, ""82 
25,556 
26,330 

27,104 
27,879 
28,653 
29,427 

3o,20I 

30,976 
3i,75o 
32,524 
33,398 
34,072 

34,846 
38,717 
42,586 
46,456 
5o,334 
54,192 

58,o6o 
6i,g37 
65,7g3 
6g,658 

73,533 

77,385 


6 
11 

■7 
22 

28 
33 
38 
43 
49 

54 
60 
65 

7' 
76 

83 
87 
92 
98 
io3 

109 
1 1 
120 

125 

i3o 

i36 
i4i 

1 47 
i53 
i57 

1 63 
169 

174 
179 
i85 

191 
195 
201 

20- 


217 
223 


234 
239 

245 
273 

3oo 
326 
354 
38 1 

4o8 
435 
463 
490 

5l7 

545 


25.2050 


0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 

o,oo36 
0,0049 
0,0064 
0,0081 

0,0100 
0,0121 
o,oi44 
0,0169 
0,0196 

0,0225 
o,o256 
0,0289 
o,o334 
o,o36i 

o,o4oo 
o,o44i 
o,o484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,084 1 

0,0900 
o,og6i 
0,1024 
o,io8g 
0,1 156 

0,1225 
0,1396 
0,1369 
0,1 444 

0,l53I 

0,1600 
o,  1 68 1 
o,  1 764 
0,1 84g 
o,ig36 

O,3035 

o,25oo 
o,3o35 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 


(  Î-  4-  r")-     or 


+ 


nearly. 


723 

726 

729 

732 

735 

733 

741 

744 

747 

75o 

753 

756 

759 

762 

765 

768 

771 

774 

777 

72 

73 

73 

73 

74 

74 

74 

74 

75 

75 

75 

76 

76 

76 

77 

77 

77 

77 

78 

i45 

i45 

i46 

i46 

l47 

1 48 

i48 

1 49 

1 49 

i5o 

i5i 

i5i 

l52 

1 52 

I53 

1 54 

1 54 

1 55 

i55 

217 

218 

219 

220 

221 

221 

222 

223 

224 

225 

226 

227 

228 

229 

230 

23o 

23l 

232 

233 

289 

290 

292 

293 

294 

295 

296 

298 

299 

3oo 

3oi 

3o2 

3o4 

3o5 

3o6 

307 

3o8 

3io 

3ii 

362 

363 

365 

356 

368 

35o 

.371 

372 

374 

375 

377 

378 

3So 

38 1 

383 

384 

386 

387 

38q 

434 

436 

437 

439 

441 

443 

445 

446 

448 

45o 

452 

454 

455 

457 

459 

461 

463 

464 

466 

5o6 

5o8 

5io 

5l3 

5i5 

517 

5 10 

521 

523 

525 

527 

52q 

5Ji 

533 

536 

538 

540 

542 

544 

578 

58t 

583 

586 

588 

590 

5q3 

5q5 

5qS 

600 

603 

6o5 

607 

610 

bl2 

614 

6.7 

619 

622 

65 1 

653 

656 

659 

652 

664 

667 

670 

672 

675 

678 

b8o 

68J 

686 

689 

691 

694 

697 

6g9 

TABLE 

II. 

—  To  fi 

ml  tlie  tiiiifc 

T 

the  sum  of  (lie  railii  r +  )■'', 

and  the  cliord  i 

being  given. 

Sum  of  the  Ita.lii  r-f-r".                                                                                                                   | 

Cliord 

c. 

7,-20 

7,30 

Days  |dif. 

7,40 

7,50 

7,60 

7,7 

0 

7,80 

Days  Idif. 

7,90 

8,00 

8,10 

Days  |(lil". 

Days  |(lif. 

Days  Idif 

Days  Idif. 

Days 

dir: 

Days  Idif. 

Days  Idif. 

Days  |dif. 

0,00 

0,0(I0 

0,000 

0,000 

0,000 

0,000 

0.f)00 

0,000 

0,0O(j 

0,000 

0,000 

o,cooo 

0,01 

0,780 

5 

0,785 

6 

0,701 

5 

0,-96 

5 

0,801 

6 

oi8o- 

5 

0,812 

5 

0,817 

5 

0,822 

5 

0,827 

5 

0,0001 

0,02 

i,56o 

1 1 

.,571 

10 

i,58i 

11 

1,592 

11 

i,6o3 

i(ï 

i,6i3 

1 1 

1,()34 

10 

1.634 

10 

1,644 

10 

1,654 

11 

o,ooo4 

o,o3 

2,34o 

16 

2,356 

16 

2,372 

16 

2,388 

16 

2,4o4 

16 

2,420 

i5 

2,435 

i(i 

2,45i 

i5 

2,466 

16 

2,482 

i5 

0,0009 

o,o4 

3,120 

21 

3,i4i 

22 

3,i63 

21 

3,184 

21 

3,2o5 

21 

3,226 

21 

3,247 

21 

3,268 

20 

3,288 

21 

3,309 

20 

0,0016 

o,o5 

3,900 

27 

3,927 

26 

3,953 

27 

3,980 

27 

4,007 

26 

4,o33 

26 

4,059 

26 

4,o85 

26 

4,111 

25 

4,1 36 

26 

0,0025 

0,06 

4,680 

32 

4,712 

32 

4,744 

32 

4,776 

32 

4,808 

3i 

4,839 

32 

4,871 

3i 

4,902 

3i 

4,933 

3o 

4,963 

3i 

o,oo36 

0,07 

5,459 

38 

5,497 

38 

5,535 

37 

5,572 

37 

5,609 

37 

5,646 

36 

5,682 

37 

5.719 

36 

5,755 

36 

5,791 

35 

0,0049 

0,08 

6,239 

44 

6,283 

42 

6,325 

43 

6,368 

42 

6,410 

42 

6,452 

42 

6,494 

42 

6,536 

41 

6,577 

4i 

6,618 

4i 

0,0064 

o,og 

7,019 

49 

7,068 

48 

7,116 

48 

7,164 

48 

7,212 

47 

7.259 

47 

7,3o6 

47 

7,353 

46 

7,399 

46 

7,445 

46 

0,0081 

0,10 

".799 

54 

7,853 

54 

7.907 

53 

7,960 

53 

8,0 1 3 

52 

8.065 

53 

8,118 

52 

8,170 

5i 

8,221 

5i 

8,272 

5i 

0,0100 

0,1 1 

8,579 

5o 

8,638 

59 

8,(197 

59 

8,756 

58 

8,81 4 

58 

8,872 

57 

8,929 

58 

8,987 

56 

9,043 

57 

g,ioo 

56 

0,0121 

0,12 

9,359 

65 

9.424 

64 

9,488 

64 

9,552 

63 

9,61 5 

64 

9, •'79 

62 

9.741 

62 

9,8o3 

63 

9,865 

62 

9.927 

61 

0,01 44 

o,i3 

10,139 

70 

10,209 

70 

10,279 

69 

10,348 

69 

io,4i7 

68 

io,485 

68 

10,553 

67 

10,620 

67 

10,687 

67 

10,754 

66 

0,0169 

o,i4 

10,919 

75 

10,994 

75 

11,069 

75 

ii,i44 

74 

11,218 

74 

11,292 

73 

11,365 

72 

11.437 

72 

ii,5og 

72 

ii,58i 

71 

0,01 96 

0,1 5 

11,699 

81 

11.780 

80 

11,860 

80 

1 1 ,940 

79 

12,019 

79 

1 2 ,098 

78 

12,176 

78 

12,254 

78 

12,332 

76 

12,408 

77 

0,0225 

0,16 

12,4-9 

86 

12,565 

86 

1 2,65 1 

85 

12,736 

85 

12.821 

84 

1 2 ,905 

83 

1 2, 988 

83 

13,071 

83 

i3;i54 

82 

i3,236 

81 

0,02  56 

0,17 

1 3,208 

92 

i3,35o 

9' 

i3,44i 

9' 

i3,532 

90 

13,622 

89 

l3,7Il 

89 

1 3,800 

88 

1 3,888 

88 

■3,976 

87 

i4,o63 

86 

0,0289 

0,18 

i4.o38 

q8 

i4,i36 

96 

l4.232 

96 

14,328 

95 

i4,423 

95 

i4i5i8 

94 

i4,6i2 

93 

i4,7o5 

93 

14,798 

92 

i4,8go 

92 

o,o324 

0,19 

14,818 

io3 

14,921 

102 

1 5,023 

101 

i5,i24 

100 

1 5,224 

100 

1 5,324 

99 

i5,423 

99 

l5,522 

98 

15,620 

97 

15,717 

97 

o,o36i 

0,20 

15,598 

108 

15,706 

107 

i5,8i3 

107 

15.920 

106 

16,026 

io5 

i6,i3i 

io4 

16,235 

io4 

16,339 

io3 

16.443 

102 

16,544 

102 

o,o4oo 

0,21 

16,3-8 

ii3 

16.491 

ii3 

16,604 

112 

16,716 

111 

16,827 

no 

16,937 

£10 

17,047 

log 

17,1 56 

108 

17,264 

iû8 

17,372 

106 

o,o44 1 

0,22 

1 7, 1 58 

118 

17,276 

118 

17,394 

118 

I7,5i3 

116 

17,628 

116 

17,744 

ii4 

17,858 

ii5 

17-973 

ii3 

18,086 

ii3 

18,199 

112 

o,o484 

0,23 

I -.938 

124 

18,062 

123 

i8,i85 

123 

i8,3o8 

121 

18,429 

121 

i8,55o 

120 

18.670 

'■9 

18,789 

119 

l8,go8 

118 

1 9,026 

117 

0,0529 

0,24 

18.71: 

i3o 

18,847 

129 

18,976 

127 

ig,io3 

127 

1 9,23o 

127 

19,357 

125 

19,482 

124 

ig,6o6 

124 

19,730 

123 

19,853 

122 

0,0576 

0,25 

19.497 

i35 

19,632 

i34 

19,766 

i33 

19,899 

i33 

20,o32 

i3i 

20,i63 

i3o 

20,393 

i3o 

20,423 

12g 

20,552 

128 

20,680 

127 

0,0625 

0,26 

20,277 

i4o 

20,417 

t4o 

20,557 

1 38 

20,695 

1 38 

2o,833 

1 36 

20,96g 

1 36 

2I,105 

i35 

21,240 

i34 

21,374 

1 33 

2I,507 

i33 

0,0676 

0,27 

2l,o57 

i46 

2!,203 

i44 

21,347 

144 

2M91 

i43 

21,634 

142 

21,776 

i4i 

21,917 

i4o 

2  2,o57 

1 39 

22,196 

i38 

22,334 

i38 

0,072g 

0,28 

21,837 

i5i 

21,988 

i5o 

22,l38 

i4g 

22,287 

148 

22.435 

147 

22,582 

i46 

22,728 

i46 

22,874 

1 44 

23,018 

i44 

23,162 

142 

0,0784 

0,29 

22,616 

1 57 

22,773 

1 55 

22,928 

1 55 

23,o83 

1 53 

23;236 

i53 

23,389 

IDl 

23,540 

i5i 

23,691 

149 

23,840 

i4g 

23,989 

i47 

0,084 1 

o,3o 

23,396 

162 

23,558 

161 

23,719 

i6o 

23,879 

1 58 

24,037 

i58 

24,195 

1 57 

24,352 

i55 

24,507 

i55 

24,662 

i54 

34,816 

l52 

0,0900 

0,3 1 

24,176 

167 

24,343 

166 

24,509 

166 

24,675 

164 

24,889 

162 

25,001 

162 

25,i63 

161 

25,324 

16c 

25,484 

159 

25,643 

i58 

0,0961 

0,32 

24,956 

172 

25,128 

172 

25,3oo 

170 

25,470 

170 

25.640 

168 

25.808 

167 

25.975 

166 

26,141 

i65 

26,306 

164 

26,470 

i63 

0,1024 

0,33 

25-35 

179 

25.914 

176 

26,090 

176 

26,266 

175 

26,441 

173 

26,614 

173 

26:787 

171 

26,958 

170 

27,128 

169 

27,297 

168 

0,1089 

0,34 

26,5i5 

184 

26,699 

182 

26,881 

181 

27,062 

180 

27,242 

179 

27,421 

177 

27,598 

177 

27,775 

175 

27,950 

174 

28,124 

173 

0,11 56 

0,35 

27,295 

189 

27,484 

187 

27,671 

187 

27,858 

i85 

28,043 

184 

28,227 

i83 

28,4i<;' 

181 

28,5gi 

181 

28,772 

179 

28,95] 

.78 

0,1225 

o,36 

28,074 

195 

28,269 

ig3 

28,462 

192 

28,654 

190 

28,844 

189 

2g,o33 

186 

29,221 

187 

29,408 

186 

29.594 

184 

29,778 

i83 

0,1296 

0,37 

28,854 

200 

29.054 

198 

29,252 

197 

2gMg 

196 

29,645 

195 

29.840 

ig3 

3o,o33 

192 

3o,225 

'9' 

3o,4i6 

189 

3o,6o5 

i8g 

0,1369 

o,38 

29,634 

205 

29,839 

204 

3o.o43 

202 

30,245 

201 

3o,446 

200 

3b;646 

198 

3o,844 

198 

3 1, 042 

195 

3 1,237 

ig5 

3 1,432 

ig4 

0,1444 

0,39 

3o,4t3 

211 

30,624 

209 

3o;833 

208 

3i,o4i 

206 

3 1, 247 

205 

3i,452 

204 

3 1, 656 

202 

3 1, 858 

201 

32,o5g 

200 

32,259 

199 

0,l52I 

0,40 

31,193 

216 

3 1 ,409 

2l5 

31,624 

2l3 

3 1, 837 

211 

32,o48 

211 

32,259 

208 

33,467 

208 

32,675 

2g6 

33,881 

2o5 

33,086 

204 

0,1600 

o,4i 

31.973 

221 

32,ig4 

220 

32,4i4 

218 

32,632 

217 

32.840 

216 

33,o65 

214 

33,279 

2l3 

33,492 

211 

33,7o3 

210 

33,913 

3t)g 

0,1681 

0,42 

32,752 

227 

32,979 

225 

33,204 

'>o4 

33,428 

222 

33,650 

221 

33,871 

219 

34,090 

218 

34,3o8 

217 

34,525 

2l5 

34,740 

2l4 

0, 1 764 

0,43 

33,532 

232 

33,764 

23l 

33,995 

229 

34,224 

227 

34,451 

226 

34,677 

225 

34,902 

223 

35,125 

222 

35,347 

220 

35,567 

2iq 

0,1849 

0,44 

34,3 11 

238 

34,549 

236 

34,785 

234 

35,019 

233 

35,252 

232 

35,484 

22g 

35,7i3 

229 

35,942 

227 

36,i6g 

225 

36,394 

224 

0,1936 

0,45 

35,091 

243 

35,334 

241 

35,575 

240 

35,8i5 

238 

36,o53 

237 

36,390 

235 

36,525 

233 

36,758 

232 

36,990 

23l 

37,221 

229 

0,3035 

o,5o 

38,989 

270 

39,259 

268 

39,527 

266 

39,793 

265 

4o,o58 

263 

4o,32i 

261 

40,582 

259 

4o,84i 

258 

41,099 

256 

41,355 

255 

0,2  5oo 

0,55 

42,886 

297 

43,183 

295 

43,478 

293 

43,77. 

291 

44,062 

289 

44,35 1 

287 

44,638 

28(3 

44,924 

283 

45,207 

282 

45,489 

380 

o,3o25 

0,60 

46,782 

324 

47,106 

332 

47,428 

320 

47,748 

3i7 

48,o65 

3i6 

48,38 1 

3i3 

48,6g4 

3l2 

49,006 

309 

4g,3i5 

3o8 

4g,623 

3o6 

o,36oo 

o,65 

50,678 

35i 

51,029 

349 

51,378 

346 

51,724 

345 

52,069 

34! 

52.410 

340 

52,750 

337 

53,087 

336 

53,423 

333 

53.756 

33i 

0,4225 

0,70 

54,573 

379 

54,952 

375 

55,327 

373 

55,700 

371 

56,071 

368 

56;439 

366 

56,8o5 

364 

57,169 

36i 

57,53o 

359 

57,88g 

356 

0,4900 

0,75 

58,468 

4o5 

58,873 

4o3 

59,276 

400 

59,676 

397 

60,073 

395 

60,468 

392 

60,860 

389 

61,249 

387 

6 1,636 

385 

63,021 

382 

o,5625 

0,80 

62,362 

432 

62,794 

43o 

63,224 

427 

63,65 1 

423 

64,074 

421 

64,495 

418 

64  91 3 

4i6 

65,32y 

4i3 

65,742 

4io 

66,1 52 

408 

o,64oo 

0,85 

66,255 

460 

66,7 1 5 

456 

67,171 

454 

67,625 

45o 

68,075 

447 

68,5"22 

445 

68.967 

441 

69,408 

439 

69,847 

436 

70,283 

433 

0,7325 

0,90 

70,148 

486 

70,634 

484 

71,118 

480 

71,598 

477 

72,075 

473 

72,548 

471 

73,019 

468 

73,487 

464 

73,951 

462 

74,4 1 3 

45g 

0,8100 

0,95 

74,039 

5i4 

74,553 

5io 

75,o63 

5o7 

75,570 

5o4 

76,074 

5oo 

76,574 

497 

77,071 

4g3 

77,564 

491 

78,055 

487 

78,542 

485 

0,9025 

1,00 

77,930 

54 1 

78,471 

537 

79,008 

534 

79,542 

53o 

80,072 

527 

80,599 

523 

81,122 

519 

8i,64i 

5i7 

83,i58 

5i3 

82,671 

5io 

1 ,0000 

25,9200l 

26,64501 

27,38001 

28,12501 

28,88001 

29,64501 

30,42 

00 

31,20501 

32,0000| 

32,80501 

i   .  (  r  -f-  r  "  J  ^    or    f^  -f*  **  '^    nearly.                                                                                                     | 

7-9 

-82 

7S5 

7S8 

I 

78 

78 

79 

79 

2 

i56 

1 56 

1D7 

1 58 

3 

234 

235 

236 

236 

4 

3l2 

3i3 

3i4 

3i5 

5 

390 

391 

393 

3q4 

6 

467 

469 

471 

473 

7 

545 

547 

55o 

552 

8 

623 

626 

628 

63o 

9 

701 

704 

707 

709 

79' 

794 

797 

800 

£o3 

806 

8cg 

812 

8i5 

818 

821 

834 

79 

79 

80 

80 

80 

81 

81 

81 

82 

82 

82 

82 

1 58 

i5q 

i59 

160 

161 

161 

162 

162 

1 63 

164 

164 

1 65 

237 

23ii 

339 

340 

241 

242 

s43 

244 

245 

245 

246 

247 

3i6 

3i8 

3ip 

320 

321 

322 

324 

325 

326 

327 

328 

33o 

396 

397 

3qc, 

400 

4o2 

4o3 

4o5 

4c6 

4o8 

409 

4ii 

4l2 

475 

4-6 

478 

480 

482 

484 

485 

487 

489 

4qi 

4q3 

494 

554 

556 

558 

56o 

562 

564 

566 

568 

571 

573 

575 

577 

633 

635 

638 

640 

642 

645 

647 

65o 

652 

654 

657 

65q 

712 

7i5 

717 

720 

723 

725 

728 

73i 

734 

736 

739 

742 

827 

83o 

83 

83 

i65 

166 

248 

249 

33i 

332 

4i4 

4i5 

4q6 

498 

579 

58 1 

662 

664 

744 

747 

TABLE  II.  —  To  find  the  time  T;  the  sum  of  the  radii  r-\-r'\  and  the  chord  c  being  given. 

Sum  of,  the  Radii   r-\-r". 


Chord 
C. 


0,00 
0,01 

0,02 

o,o3 
o,o4 

o,o5 
0,06 
0,07 
0,08 
0,09 

0,10 
0,11 
0,12 
0,1 3 
o,i4 

o,i5 
0,16 
0,17 
o,iS 
'•9 

0,30 
0,21 
0,22 

0,23 

0,24 

0,25 
0,26 
0,27 

0,28 
0,29 

o,3o 
0,3 1 

0,32 

0,33 
0,34 

0,35 
o,36 
0,37 
o,38 
0,39 

o,4o 
0,4 1 
0,42 

0,43 
0,44 

0,45 

o,5o 
0,55 
0,60 
0,65 
0,70 

0,75 
0,80 
o,85 
0,90 
0,95 


8,20 


Days  |dir. 


0,000 
0,832 
1,665 
2>497 
3,329 

4,162 
4,994 
5,826 
6,659 

7 

8,323 

9, 1 56 

9,988 

10,820 

11,652 

12,485 
1 3,3 1 7 
i4,i49 
14,983 
t5,8i4 

1 6,646 
17,478 
i8,3ii 
i9''43 
'9.975 

20,807 
2 1 ,640 
22,472 
23,3o4 
24,i36 

24,968 
25,801 
26,633 
27,465 
28,297 

29,129 
29,961 
30,794 
31,626 
32,458 

33,290 
34,122 
34,954 
35,786 
36,6 1 8 

37,450 
4 1 ,6  [  o 
45,769 

49,929 
54,087 
58,245 

62,4o3 
66,56o 
70,716 
74,873 
79,037 
83,i8i 


i5 


35 

3o 
36 
40 
45 

5i 
55 
61 
66 
71 

76 
81 
86 
91 
96 

lOI 

107 
I II 
116 
122 

127 
i3i 
1 36 
143 

147 

I  53 

1 57 
162 
167 
172 

177 
i83 
.87 
192 
197 

202 

307 

2l3 

218 

233 
328 

253 
279 

3o3 
339 
355 

38o 
4o5 
43 
456 

4i 

507 


8,30 


Diiya  Idir 


0,000 

0,837 
1,675 

2,5l2 

3,35o 

4,187 
5,024 
5,862 
6,699 
7,536 

8,374 

9,211 

10,049 

10,886 

11,723 

i2,56i 
13,398 
i4,235 
15,073 
15,910 

16,747 
17,585 
18,432 
19,259 
20,097 

30.934 
21,771 
33,608 
33,446 
24,283 

25,120 
2  5,958 
26,795 
27,633 
28,469 

29,306 
3o,  1 44 
30,981 
3i,8i8 
32.655 

33,492 
34,339 
35,167 
36,oo4 
36,84 1 

37,678 
4 1, 863 
46,o48 

5o,333 

54,4i6 
58,6oo 

62,783 
66,965 

71,147 
75,328 
7q.5o8 
83,688 


i5 


3o 
35 
4o 
46 

5o 
56 
6< 
65 
71 

75 
80 
86 
90 
9G 

101 
io5 
11 1 
116 

130 
136 

i3i 
i36 
i4i 
1 46 

i5i 
■  55 
161 
166 
171 

176 


33,6200 


19' 
196 

202 
207 
211 
316 
221 

326 

252 

277 

3o2 

327 

352 

377 
40  3 
43 
453 

479 
5o4 


8,40 


Duys  Idif. 


0,000 
0,842 
1,685 
2,527 
3,370 

4,212 

5,o54 
5,897 
6,739 
7,583 

8,434 

9,367 

10,109 

10,951 

1 1 ,794 

13,636 
13,478 
i4,33i 
i5,i63 
16,006 

16,848 
17,690 
18,533 
19,375 
20,217 

2 1 ,060 
21,902 

3  2,744 

23,587 
24,429 

25,271 
26,1 13 
26,956 
27,798 
28,640 

39,483 
3o,325 
31,167 
33,009 
32,85i 

33,694 
34,536 
35,378 
36, 220 
37,063 

37,904 
43,ii5 
46,335 
5o,534 
54,743 


5o 
55 
60 
65 

70 

75 
80 
85 
90 
95 

100 
io5 
110 
ii5 
120 

125 
i3o 
i35 
i4o 
145 

i5o 
i55 
160 
i65 
170 

176 
180 
i85 
19( 
195 

200 

205 
210 
2l5 
220 

225 
25o 
375 

3oo 
326 


34,4450 


58,952  35o  59,302 


63, 160 
67,368 
71,575 
75,781 
79-987 
84,192 


8,50 

"Days  |dil'. 


376 

4oo 
435 
45i 
476 
5oi 


35,2800 


0,000 
0,847 
1,695 
2,542 
3,390 

4,237 

5,û84 
5,932 

6,779 
7,627 

8,474 

9,322 

10,169 
11,016 
11,864 

13,711 
1 3,558 
i4,4o6 
1 5,253 
16,101 

16,948 

17,795 
18,643 
19,490 
20,337 

2i,i85 

3  2,o33 
22,879 
23,727 
24,574 

25,421 
26,268 
27,1  16 
27,963 
28,810 

29,658 
3o,5o5 
3i,352 
32,199 
33,046 

33,894 
34,741 
35,588 
36,435 
37,282 

38,129 
42,365 
46,600 
5o,834 
55,069 


63,536 
67,768 
73,000 
76,232 
8o,463 
84,693 


i5 
20 

25 

3o 
35 
40 

5o 
54 
60 
65 
69 

75 
80 
84 
9" 
94 

99 
io5 
109 
114 
120 

134 

129 

35 

139 

i44 

i49 
i55 
159 
164 
169 

174 
179 
184 
189 
194 

198 

3o4 
209 
2l4 

219 

224 

2 
373 

299 
323 
349 

373 
398 

423 

448 
473 
4q8 


8,60 


Days  |dif. 


0,000 
0,853 
i,7o5 
3,557 
3,4io 

4,363 
5,114 
5,967 
6,819 

7,671 

8,524 

9,376 

10,329 

1 1 ,08 1 

1 1,933 

12,786 
1 3,638 
14,490 
15,343 
16,195 

17,047 
17,900 
18,752 
19,604 
20,457 

21,309 
22,161 
23,014 
2  3,866 
34,71 

35,570 
26,433 
27,275 
28,127 
28,979 

39,833 
3o,684 
3i,536 
32,388 
33,240 

34,092 

34,945 

35,79 

36,649 

37,501 

38,353 
42,61 3 
46,873 
5i,i33 
55,393 
59,65i 


36,1250 


94 

99 
io3 
109 
114 
118 

134 

'29 

33 

i3S 

143 

149 
i53 
1 58 
i63 


173 
178 
i83 
188 
193 

1Ç 

202 
207 

313 
217 

223 
248 
272 

297 
331 

346 


63,90g  371  64,280 


68,166 

72,423 

76,680 
80,936 

85,191 


8,70 


Days  Irtif. 


0,000 
0,857 

1,71 5 
2,572 
3,429 

4,287 
5,144 
6,001 
6,859 

7,716 

8,573 

9,43 1 

10,288 

11,145 

13,002 

T  2,860 
13,717 
1 4,574 

i5,432 
16,289 


17,146 

i8,oo3 

18,861 

19,718 

20,575 

21,433 

22,290 

23,147 

24.004 

24,861 

25,719 
26,576 

27,433 

28,290 
29,147 

3o,oo4 
30,862 
31,719 
32,576 
33,433 

34,290 
35,147 
36 ,004 
36,86i 
37,718 

38,576 
42,861 
47,145 
5i,43o 
55,7i3 
59,997 


396 
421 
445 
470 
495 


36,9800 


562 
72,844 
77,125 
81,406 
85,686 


127 
1 33 
i38 
i43 

1 47 

I  52 

'57 
162 
167 

173 

177 

1S2 

it 

192 

'97 
202 
207 
212 
217 

231 
245 
371 
295 
320 


369 
394 
418 
443 
467 

492 


8,80 


Days  Idif. 

0,000 

0,862 

1,724 

2,587 

3.449 


37,8450 


4,3ii 
5,173 
6,o36 
6,898 
7,760 

8,622 

9,485 
10,347 
1 1,209 
12,071 

12,933 
1 3,796 
1 4,658 
1 5,520 
1 6,38 2 

17,244 
18,107 
18,969 
i9,83i 
2o,6g3 

21,555 
22,417 
33,280 
24,143 
25,oo4 

25,866 
26,728 
27,590 
28,452 
29,314 

30,176 
3 1, 039 
3 1 ,90 1 
32,763 
33,625 

34.487 
35,349 
36,2 1 1 
37,073 
37,935 

38,797 
43,106 
47,416 
5i,725 
56,o33 
60,341 

64,649 
68,956 
73,262 
77,568 
81,873 
86,178 

38,7200 


25 

3ù 
34 
39 
AA 

49 
53 
58 
64 
69 

74 
78 
83 
88 
93 

98 
102 
107 
112 
117 

122 
128 

l32 

'37 
142 

■47 

I  52 

'57 
162 
167 

172 
175 
180 
i85 
190 

195 
200 
2o5 

310 
2l5 

220 
245 
268 
293 

3'r 
342 

366 
391 
4i6 
440 
465 


,90 


Days 


0,000 
0,867 
1,734 
2,601 
3,469 

4,336 
5,2o3 
6,070 
6,937 
7,804 

8,671 

9,538 

io,4o5 

1 1,273 

12,l4o 

13,007 
13,874 
'4,74' 
1 5,608 
16,475 

17,342 
18,209 
19,076 
19,943 
20,810 

21,677 
22,545 
23,4 12 
24,279 
25,146 

26,013 
26,880 

27,747 
28,614 
29,481 

3o,348 
3 1,2 1 4 
32,081 
32,948 
33,81 5 

34,683 
35,549 
36,4' 6 
37,283 
38,1 5o 

39,017 
43,35i 
47,684 
52,018 
56,35 1 
6o,683 

65,oi5 
69,347 
73,678 
78,000 
82,338 
86,667 


5 
10 
i5 
'9 

24 
29 
34 
39 
AÂ 

49 

54 

59 
63 
68 

73 
78 
83 
87 
92 

97 
102 
107 
112 
117 

122 
126 
i3i 
1 36 

i4o 

145 
i5o 
i55 
160 
i65 

170 
175 
180 
i85 
190 

'95 
199 
204 
209 

2l4 

21 

343 

368 

391 

3i6 

341 

36: 
389 

4i3 
438 
462 

487 


39,6050 


9,00        9,10 


Days  |dir. 


Days 


0,000 

0,000 

0,873 

5 

0,877 

1,744 

10 

1,754 

3,616 

14 

3,63o 

3,488 

19 

3,5o7 

4,36o 

24 

4,384 

5,333 

29 

5,361 

6,104 

M 

6,1 38 

6,976 

3q 

7,01 5 

7,848 

Ai 

7,891 

8,730 

48 

8,768 

9,592 

53 

9,645 

10,464 

58 

10,522 

11,336 

63 

1 1 ,399 

12,208 

67 

12,275 

1 3,080 

72 

i3,i52 

13,952 

77 

14,039 

14,824 

82 

14,906 

15,695 

87 

15,782 

16,567 

92 

16,659 

17,439 

97 

17,536 

i8.3i[ 

102 

i8,4i3 

19,183 

lOb 

19,289 

2o,o55 

1 11 

20, 1 66 

20,927 

116 

2 1 ,043 

21,799 

121 

2 1 ,920 

22,671 

125 

22,796 

23,543 

i3o 

23,673 

24,41 5 

i35 

24,55o 

25,286 

i4i 

25,427 

36,1 58 

145 

26,3o3 

27,o3o 

i5o 

27,180 

27,902 

i55 

28,057 

28,774 

159 

28,933 

29,646 

104 

29,810 

3o,5i8 

i6q 

30,687 

3 1,389 

174 

3 1,563 

32,261 

'79 

32,44o 

33,i33 

1 84 

33,3 17 

34,oo5 

188 

34,193 

34,877 

iq3 

35,070 

35,748 

,p8 

35,946 

36,620 

20  J 

36,823 

37,492 

308 

37,700 

38,364 

212 

38,576 

39.235 

218 

39.453 

43,594 

341 

•43.835 

47,952 

2fab 

48,218 

52,309 

390 

52,5g9 

56,667 

3i4 

56,981 

61,024 

338 

61,362 

65,38o 

363 

65,743 

69,736 

^87 

70,123 

74,091 

4.1 

74,5o2 

78,446 

435 

78,881 

82,800 

460 

83,260 

87,154 

483 

87,637 

40,5( 

)00 

41,40.50 

0,0000 
0,0001 
0,0004 
0,0009 
0,0016 

0,0025 
o,oo36 
0,0049 
o,où64 
0,008 1 

0,0100 
0,0121 
0,01 44 
0,0169 
0,0196 

0,0225 
0,0256 
0,0289 
o,o324 
o,o36i 

o,o4oo 
o,o44 1 
o,o484 
0,0529 
0,0576 

0,0625 
0,0676 
0,0729 
0,0784 
0,0841 

0,0900 
0,0961 
0,1024 
0,10 
0,11 56 

0,1225 
0,1296 
0,1369 
0,1444 

0,l52I 

0,1600 

0,1681 

0,1764 
0,1849 
0,1936 

0,2025 
o,25oo 
o,3o25 
o,36oo 
0,4225 
0,4900 

0,5625 
o,64oo 
0,7225 
0,8100 
0,9025 
1 ,0000 


\ 

■  (»■  + 

r"  )^  0 

r=  + 

"  -   no;t 

rlv. 

832 

835 

838 

84' 

844 

847 

85o 

853 

856 

859 

S62 

865 

868 

871 

874 

877 

83 

84 

84 

84 

84 

85 

85 

85 

86 

86 

86 

87 

87 

87 

87 

88 

166 

167 

168 

168 

i6q 

i6q 

170 

171 

171 

172 

172 

173 

174 

174 

175 

175 

25o 

25l 

25l 

252 

253 

254 

255 

256 

257 

258 

2  5q 

260 

260 

261 

262 

263 

333 

334 

335 

336 

333 

339 

34o 

34 1 

342 

344 

345 

346 

347 

348 

35o 

35i 

416 

4i8 

4'9 

421 

422 

424 

425 

427 

428 

43o 

43i 

Aii 

434 

436 

437 

fî 

4q9 

5oi 

5o3 

5o5 

5o6 

5o8 

5io 

5l2 

5i4 

5i5 

5l7 

519 

521 

523 

524 

526 

582 

585 

587 

589 

5qi 

5q3 

5q5 

5q7 

5qq 

601 

60  3 

606 

608 

610 

612 

6i4 

666 

668 

670 

673 

675 

678 

6S0 

63  2 

685 

687 

6go 

6q2 

694 

697 

699 

702 

749 

752 

754 

757 

760 

762 

765 

768 

770 

773 

776 

779 

781 

784 

787 

789 

TABLE  III. 

This  fable  gives  llie  true  anomaly  U  of  a  comet,  moving  in  a  parabolic  orbit,  whose  perihelion  distance  is  equal  to 
the  ine.in  ili<taiice  of  the  sun  from  tlie  earth  or  uniti/  ;  tlic  time  from  the  perihelion  being  /'   days.     It  was  computed 
by  Uurckhardt,  by  means  of  the  formula  in  book  ii.  §  23,  Mécanique  Celeste,  [693  &.C.],  namely, 
<'  =  27''''-",4038  .  .  .  X^Stang.  àt/+tang.3  )^u\. 

If  the  perihelion  distance  be -D,  and  the  time  from  the  perihelion  t  days,  we  must  put<  =  i»3't'  [693a].  If  [7  be 
given,  we  must  iind,  in  this  table,  the  corresponding  value  of  log.  t',  and  then  the  value  of  t  from  the  formula, 

log. /  =  log.  r+f  log.  I>. 
But  if  t  he  given,  we  must  first  find 

log.  r  =  log.  t  —  f  log.  D  ; 
and  then  from  this  table  the  value  of  U,  corresponding  to  this  value  of  log.  ('. 

When  t'  is  less  than  5  days,  the  différences  of  log.  ('  vary  so  rapidly,  that  it  is  found  convenient  to  vary  the  form  of  this 
part  of  the  table.  This  is  done  by  two  ditierent  methods  ;  the  one  proposed  by  Burckhardt,  the  other  by  Carlini  ;  by 
means  of  the  fust  six  columns  of  the  first  page  of  Table  III.  Burckhardt's  method  consists  in  finding  (',  from  log.  ('  ; 
and  then,  with  the  argument  t',  we  obtain  the  corresponding  value  of  U,  as  in  the  first  three  columns  of  the  table.  In 
the  next  three  columns,  which  contain  the  table  of  Carlini,  the  argument  is  log.  (',  as  in  all  the  rest  of  the  table,  and  the 

corresponding  number  is  log.  - ,  or  log.  U —  log.  t' ;   U  being  expressed  in  sexagesimal  minutes,  and  t',  in  days.     This 

method  of  Carlini  is  very  convenient,  in  the   case  which  most  frequently  occurs;  namely,  where  t  is  given  to  find  U  ; 
for  we  have, 

log.  V  =  log.  I  —  I-  log.  D  ; 

log.  U'ln  minutes  =  log.  f -(-tab.  number  corresponding  to  log.  t. 

In  the  determination  of  the  cimslant  factor  97  ^'',4038,  in  the  above  value  of  (',  we  have  neglected,  as  in  [G92'],  the 
mass  of  the  earth  in  comparison  with  that  of  the  sun  ;  as  is  usually  done  in  computing  tables  of  this  kind.  This  omission 
may  be  rectified,  by  adding  0,0000006  to  the  argument  log.  ('  in  the  table  ;  or  by  subtracting  0,0000006  from  the  logarithm 
oit,  in  finding  the  log.  t'. 

Tables  of  this  kind  have  been  given  by  several  authors,  as  Halley,  La  Caille,  Zach,  Pingre,  &c.  ;  but  above  all,  by 
Delambre,  who  improved  and  extended  this  table  very  much,  giving  the  values  of  U,  corresponding  to  the  argument  I', 
taken  at  convenient  intervals  from  ^'^0  to  t'^  200,000  days.  Burckhardt  made  an  important  improvement  in  Table 
III.  ;  by  taking  for  the  argument  log.  «',  ivhich  is  given  by  a  previous  calculation,  and  by  this  means  he  saves  the  labor 
of  finding  t'  from  log.  t'. 

Barker  published  a  general  table  of  the  paraboUc  motion  of  a  comet,  in  which  the  argument  is  the  true  anomaly  U, 
taken  at  intervals  of  5"'  ;  the  corresponding  numbers  are  what  he  calls  the  logarithms  of  the  mean  motion  represented  by 

log.  mean  motion  =  log.  t'  —  0,039871(j, 
and  the  numbers  in  Barker's  table  may  be  deduced  from  those  of  Burckhardt's  in  Table  III.,  by  putting 

Barker's  log.  =  Burckhardt's  log.  (Table  III.)  —  0,0398710  ; 
so  that  Table  III.,  may  be  considered  as  an  improvement  on  Barker's  table,  and  may  be  used  for  the  same  purposes  ;  the 
arguments,  however,  are  in  an   inverted  order.     The  argument  in  Barker's  table  being  the  true  anomaly   U ;  and  in 
Burckhardt's  table,  the  argument  is  the  logarithm  of  the  time  t'. 


EXAMPLES  OF  THE  USE  OF  TABLE  III. 


EXAMPLE     I. 
Given  the  log.  of  perihelion  distance,  or  log.  D.  =9,76565oo 
Time  from  perihelion  '  =49  ^^^,26281 

To  find  the  true  anomaly  U. 

f  X  log.  D,  9,6484750 

log.  t,  1, 69243 10 

log.  f:=\og.  t—  f  log.  D,  2,0439560 

In  Table  III.  90''  16'"  29^,3  corresponds  to  2,o43 

5   01  ,9  =  3i 5',8  X  0,9561 

f=9o  21    3 1  ,2 

EXA3IPI.E     III. 
Given  the  log.  of  perihelion  distance,  or  log.  D  =  o,t  35oooo 
Time  from  perihelion,  i  =  2  days. 
To  find  the  true  anomaly  U,  by  Burckhardt's  method. 


I-  X  log.  -D, 
log.  t, 

log.  ('  =  log.  t  —  J  log.  D, 
t' =  i'^''\2gS-633 
In  Table  III.  x  "^,2  corresponds  to 

Tab.  diif.  5oI^6x  0,987633  =  493^4 
Sum  is 


0,1875000 
o,3oio3oo 


=  o,ii353oo 

1   4o    20  ,6 

=        8     i5,4 
U=i    48     36 ,0 


EXAMPLE      II. 
Given  the  log.  of  perihelion  distance,  or  log.  i)  =  9,76565oo 
True  anomaly,  C7'==9o    2i"'3i,2 

To  find  (. 
Log.  2,043  Table  III.,  corresponds  to  90    16    29  ,3 

Difference,    3oi',9^         5    01  ,9 

Tabular  difference,  3i5  ,8  :  3oi  ,9  ::  0,001     :     0,0009560 
Hence  log.  t',  =2,0439560 

Add  I  log.  D,  =  9,6484750 

Sum  is  log.  (  =  log.  49  ^^',2528 


;  1,6924310 


EXAMPLE     IV. 


Given  D,    t'  as  in  example  iii.,  to  find  U,  by  Carlini's 
method. 


Table  III.,  Carlini,  log.  If— log.  t', 
Sura  is  log.   [/■=  108  ,600  =  1   48    36  ,0 


o,ii353o 
1,922298 

2,o35828 


a20 


To  find  the  true  anomaly  U,  corresponding 
perihelion  distance  is  the  same  as  the  mean  di 


TABLE  III. 

to  the  time  t'  from  the  perihelion  in  days,  in 
stance  of  the  sun  from  the  earth. 


a  parabolic  orbit,  whose 


Days 

t'. 


days 
0,0 
0,1 
0,2 
0,3 

0,5 
0,6 
0.7 

0,8 
0,9 

r,o 


2,2 

2,3 
2,4 

2,5 

2,6 

2.7 
2,8 
2,9 

3,0 
3,1 

3,2 

3,3 
3,4 

3,5 
3,6 

3,7 
3,8 

3,9 

4,0 
4,1 
4,2 

AÀ 

4,5 
4,6 
4,7 
4,8 
4,9 

5,0 
5,r 

5,2 

5,3 
5,4 

5,5 
5,6 

5,7 
5,8 

5,9 
6,0 


True 
Anom.   U. 


0,00,00,0 
0,08,21,8 
0,16,43,6 

o,25,o5,4 
0,33,27,2 

0,41,48,9 
o,5o,io,7 
0,58,32,4 
I  ,o6,54; 

I,l5,l5; 

1,23,37,4 
1,31,59,0 
1,40,20,6 
1,48,42,2 

1,57,03,7 

2,o5,25,2 

2, 1 3,46,6 
2,22,08,0 
2,30,29,4 
2,38,5o,7 

2,47,11.9 
2,55,33,1 
3,o3,54,2 

3,!2,l5,2 

3,20,36,2 

3,28,57,1 
3,37,17,9 
3,45,38,6 
3,53,39,3 
4,02,19,9 

4,10,40,4 
4,19,00,8 
4,27,21,1 
4,35,4i,3 
4,44,01,4 

4,52,21,5 
5,oo,4i,4 
5,09,01,2 
5,17,20,9 
5,25,40,6 

5,34,00,1 
5,42,19,5 
5,5o,38,7 
5,58,57,8 
6,07,16,8 

6,15,35,7 
6,23,54,4 
6,32,i3,o 
6,4o,3i,5 
6,48,49.8 

6,57,08,0 
7,05,26,0 
7,13,43,9 
7,22,01,7 
7,30,19,3 

7.38,36,7 
7,46,53,9 
7,55,11,0 
8,03,37,9 
8,11,44,7 
8,20,01,3 


Diff. 


5oi,8 
5oi,8 
5oi,8 
5oi,8 

5oi,7 

5oi,8 
5oi,7 
5oi,7 
5ox,7 
5oi,6 

5oi,6 
5oi,6 
5oi,6 
5oi,5 

5oi,5 

5oi,4 
5oi,4 
5oi,4 
5oi,3 

5oi,2 

5oi,2 
5oi,i 
5oi,o 
5oi,o 

5oo,9 

5oo,8 
5oo,7 
5oo,7 
5oo,6 

5oo,5 

5oo,4 
5oo,3 
5oo,2 
5oo,i 

5oo,i 

499'9 
499,8 

499  >7 
499.7 

499.5 

499.4 
499.2 
499.1 
499,0 

498,9 

498,7 
498,6 
498,5 
498,3 


498,0 

497.9 
497.8 
497,6 

497.4 

497.2 
497.1 

496.9 
496,8 
496,6 


(lay? 


9,00 
9,10 
9.20 

9,3o 
9.40 

9,5o 
9,60 

9.70 
9,80 

9.90 

0,00 
0,10 
0,20 
o,3o 
0,40 


o,4o 
0,4 1 
0,42 
0,43 
0,44 

0,45 
0,46 
0,47 
0,48 
0^49 

o,5o 
o,5i 

0,52 

0,53 
0,54 

0,55 
o,56 
0,57 
o,58 
0,59 

0,60 
0,61 
0,62 
o,63 
o,64 

0.65 
0,66 
0,67 
0,68 
0,69 

0,70 
0,71 


l.o^.     u 

nùnulns,      jjjg.^ 
imnu/t  log 

t'  in  days 


1,922370 
1,922370 
1,922370 
1,92236g 
1,92236b 

1,922366 

1,922364 
1,932360 
1,922354 
1,9223  ' 

1,922338 
i,9223o3 
1,922264 
1,922201 
1,933102 


,922102 
,922089 
,923076 
,923063 
,922048 

,922032 
,922016 

.921999 
,921981 
,921963 

,931944 
,921924 
,921903 
,921881 
,921858 

,921834 
,92 1 808 
,921782 
,921754 
,921725 

,921695 
,93 1 663 
,921630 
,921595 
,921558 

,921520 
.921480 
,921437 
,921393 
,921347 

,92 1 3oo 
,g2i25i 


Log.  ol 
t   days. 


0,700 
0,701 
0,703 
0,703 
0,704 

0,705 
0,706 
0,707 
0,708 
0,70g 

0,710 
0,71 1 
0,712 
0,713 
0,714 

0,71 5 
0,716 
0,717 
0,718 
0,719 

0,720 
0,721 
0,733 
0,723 
0,724 

0,735 
0,726 
0,727 
0,728 
0,729 

0,730 
0,731 
0,732 
0,733 
0,734 

0,735 

0,736 

0,73 

0,738 

0,739 

o,74o 
0,741 
0,742 
0,743 
0,744 

0,745 
0,746 
0,747 
0,748 
0,749 

0,750 
0,75 1 
0,752 
0,753 
0,754 

0,755 
0,756 
0,757 
o,758 
0,759 
0,760 


True 
Anom.   U. 


6,58,07,1 
6,59,04,6 
7,00,02,3 
7,01,00,1 
7,01,58,0 

7,02,56,1 
7,o3,54,3 
7,04,53,7 
7,o5,5i,i 
7,06,49,7 

7,07,48,5 
7,08,47,3 
7,09,46,3 
7,10,45,5 
7,11,44,8 

7.^2,44,2 

7.i3,43,7 
7,14,43,4 
7,i5,43,2 
7,16,43,2 

7,17,43,2 
7,18,43,4 
7.19.43,7 
7,20,44,2 
7,21,44,8 

7,22,45,6 
7.23,46,5 
7,24.47.5 
7.25.48,7 
7,26,50,0 

7,27,51,5 
7.28,53,1 
7,29,54,8 
7,3o,56,7 
7.31.58,7 

7,33,00,9 
7,34.o3,3 
7,35;o5,6 
7,36,o8,2 
7,37,10,9 

7,38,i3,8 
7,39,16,8 
7,40,19.9 
7,41,23,2 
7,42,26,6 

7,43,3o,2 
7,44,33,9 
7,45,37.8 
7,46,41,8 
7,47,45,9 

7,48,50,2 

7,49,54,7 
7.50,59,3 
7,52,o4,o 
7,53,08,9 

7,54,13.9 
7,55,19,1 
7,56,24,4 
7>57.29,9 
7,58,35,5 
7,59.41,3 


Diff. 


57.5 
57,7 
57,8 

57.9 
58,1 

58,2 
58,4 
58,4 
58,6 

58,8 

58,8 
59,0 
5q,2 
59,3 

59,4 

59,5 

59,7 
59,8 
60,0 

60,0 

60,2 
60,3 
60,5 
60,6 

60,8 

60,9 
61,0 
61,2 
61,3 

61,5 

61,6 
61,7 
61,9 
62,0 

62,2 

62,3 
62,4 
62,6 
62,7 

62,9 

63,0 
63,1 
63,3 
63,4 

63,6 

63,7 
63,9 
64,o 


64.3 

64.5 
64,6 
64.7 
64.9 

65,0 

65,2 
65,3 
65,5 
65,6 
65,8 
65,9 


Log.  oC 
('  day! 


0,760 
0,761 
0,762 
0,763 
0,764 

0,765 
0,766 
0,767 
0,768 
0,769 

0,770 
0,771 
0,772 
0,773 
0,774 

0,775 
0,776 
0.777 
0,778 
0,779 

0,780 
0.781 
0,782 
0,783 
0,784 

0,785 

0,786 

0,787 

0,7' 

0,789 

0.790 
o,79' 
0.792 
0,793 

0,794 

0.795 

0.796 

0.797 

0.7 

0,799 

0,800 
0,801 
0,802 
o,8o3 
0,804 

o,8o5 

0,8 

0,807 

0,808 

0,809 

0,810 
0,811 
0,812 
0,8 1 3 
0,81 4 

0,81 5 
0,816 
0,817 
0818 
0,819 
0,820 


True 
Anom.  U. 


d    m    i 
7.59.41 
8,00,47.2 
8,01,53,3 
8,03,59,5 

8,o4,o5,9 

8,o5,i2,4 
8,06,19,1 
8.07,25,9 
8^08,32,8 
8,09,39,9 

8,10,47,3 
8,11,54,6 

8,l3,02,2 

8,14,10,0 

8,15,17,8 

8,16,25,9 
8,17.34,0 
8,18,43,4 

8,19,50,9 
8,20,59,5 

8,22,08,3 

8,33,17,3 
8,34,36,4 

8,35,35,7 
8,26,45,1 

8,27,54,7 
8.29,04.4 
8,3o,i4i3 
8,3i,24,4 
8,32,34,6 

8,33,44,9 
8.34,55,5 
8,36,06,2 
8,37,17,0 
8,38,28,0 

8,39,39,2 
8,4o,5o,5 
8,43,02,0 
8.43,i3,6 
8,44,25,5 

8,45,37.4 
8,46,49.6 
8,48,01,9 
8,49,14.3 
8,50,36,9 

8,51,39,7 
8,52,52,7 
8.54,o5,8 
8,55,19,1 
8,56,33,5 

8,57,46,1 
8,58,59,9 
9,00,1 3,8 
9,01,27,9 
9,02,42,2 

9,o3,56,7 
9,05,11,3 
9,06,26,0 
9,07,41,0 
9,08,56,1 
9,10,11,4 


65,9 
66,1 
66,2 
66,4 
66,5 

66,7 
66,8 
66,9 
67,1 

67,3 

67,. 
67,6 
67,8 
67,1 

68,1 

68,1 
68,4 
68,5 
68,6 

68,8 

69,0 

69,1 
69,3 
69,4 

69,6 

69.7 

69.9 
70,1 
70,2 

70,3 

70,6 

70,7 
70,8 
71,0 

71,2 

71,3 
71,5 
71,6 
71,9 
7i>9 
72,2 
72,3 
72.4 
72,6 

72,8 

73,0 
73.1 
73,3 
73,4 
73,6 
73,8 
73.9 
74.1 
74,3 

74,5 

74,6 
74,7 
75,0 
75.1 
75,3 
75,4 


Log.  of        True 
t'  days.     Anom.   U. 


0,820 
0,821 
0,833 
0,823 
0,824 

0,825 
0,826 
0,837 
0,828 
0,829 

o,83o 
o,83i 
o,832 
o,833 
0,834 

o,83 

o,836 

0,837 

0,838 

0,839 


0.84 
0,842 
0,843 
0,844 

0,845 

o,846 

o,f 

o,84& 

0,84 

o.85o 
o,85i 
o,852 
0,853 
0,854 

o,855 
o,856 
0,857 
o,858 
0,859 

0,860 
0.861 
0,863 
o,663 


0,865 

0,866 

0,867 

0,8 

0,869 

0.870 
0^871 
0,872 
0,873 
0,874 

0,875 
0,876 
0,877 
0,878 
0,879 
0,880 


Diff. 


9,10,11,4 
9,11,26,8 
9,12,42,4 

9.13,58,2 
9,i5,i4,2 

9,i6,3o,3 
9,17,46,6 
9,19,03,1 
9,20,19,7 
9,21,36,6 

9,22,53,5 
9,24,10,7 
9,25,28,c 
9,26,45,5 
9,28,03,3 

9,29,31,1 
9,30,39,1 
9,3i,57,3 
9,33,15,7 
9,34,34,3 

9,35,53,0 
9,37,11.9 
9, 38,3 1,0 
9,39,50,3 
9,41,09,7 

9,42,39,3 
9,43,49,1 
9,45,09,1 
9.46,29,3 
9,47.49.6 

9,49,10,1 
9,5o,3o,8 
9,5 1,5 1, 7 
9,53,12,7 
9,54,34,0 

9,55,55,4 

9,57,17,0 

9.58,38,7 

10,00,00, 

10,01,22,9 

10,02,45,2 

10,04,07 

io,o5,3o,4 

10.06,53,3 

10,08,16,4 

10,09,39,6 
io,ii,o3,) 
10,12,26,7 
io,i3,5o,5 
io,i5,i4.5 

io,i6,.38,7 
io,i8,o3,i 
10,19,27,6 
10,20,53,4 
10,22,17,3 

10,23,43,5 
10,25,07,8 
10,26,33,3 
10,27,59,0 
10,29,34,9 
io,3o,5i,o 


75.4 
75,6 
75,8 
76,0 

76,1 

76.3 
76,5 
76,6 
76,9 

76,9 

77,2 
77.3 
77.5 

77.7 

77,9 
78,0 
78,2 
78,4 
78,6 

78,7 

78,9 
79,' 
79,3 
79,4 

79,6 

79,8 
80,0 
80,2 
80,3 

80,5 

80,7 
80,9 
81,0 
81,3 

81,4 

81,6 
81,7 
82,0 
82,2 

82,3 

82,5 
83,7 
82,9 
83,1 

83,2 

83,5 
83,6 
83,8 
84,0 

84,2 


84,9 

85,2 

85,3 
85,5 
85,7 
85,9 
86,1 
86,3 


TABLE    III. 

To  finil  the  truc  anomaly  f,  con-esponilinn   to  the   time   /'from   the  peiihelion  in  days,  in  a  parabohc  orbit,  whose   perihelion 
ilijt.incc  is  tliesanie  as  the  mean  ilistance  of  tlie  sun  from  the  eartli. 


t'  days. 


0,880 

0,881 

0,882 

0,88 

0,884 

0,885 

0,886 
0,887 
0,888 
0,889 

0,890 
0,891 
0,895 
0,893 
0,894 

0,895 
o,8g6 
0,897 
0,898 
0.899 

0,900 
0,901 
0,902 
0,903 
0,904 

0,905 
0,906 
0,907 
0,908 
0,909 

0,910 
o.gii 
0,912 
0,913 
0,914 

0,915 
0,916 

0,91 

0,918 

0,919 

0,920 
0,921 

0,923 
0,923 
0,924 

0,925 
0,926 
0.927 
0,928 
0,929 

0,930 
0,931 
o,g33 
0,933 
0,934 

0,935 
0,936 
o,g3- 
0,938 

0,939 
0,940 


Truo 
Anoiii.  U. 


o,3o,5i ,0 
0,32,17,3 
0,33,43,7 
0,35,10,4 
0,36,37,2 

0,38,04,3 
0,39,31,5 
0,40,59,0 
0,43,26,6 
0,43,54,4 

0,45,22,4 
o,46,5o,7 
0,48,19,1 
0,49,47,7 
o,5i,i6,5 

0,52,45,5 
0,54,14,7 
0,55,44,1 
0.57,13,7 
o;58,43,5 

,oo,i3,5 
,01,43,7 
,o3.i4, 1 
,04,44,7 
,06,1 5,5 

,07,46,5 
,09,17,7 
,10,49,1 
,12,20,7 
,i3,52,5 

, 1 5,24,6 
,i6,56,8 
,18,29,2 
,20,01 ,9 
,21,34,7 

,23,07,7 
,24,41,0 
,26,14,4 
,27,48,1 
,29,22,0 

,3o,56,o 
,32,3o,3 
,34,04,8 
,35,39,5 
,37,14,4 

,38,49,5 
,40,24.8 
,43,00,4 
,43,36,1 
,45,12,1 

.46,48,3 
,48,24,6 
,5o.oi,3 
,5i,38,i 
,53,i5,i 

,54,53,3 

,56,29,8 

,58,07,5 

-,59,45.3 

3,01,23,5 

2,o3,oi,S 


86.3 
86,4 
86,7 
86,8 

87,1 

87,2 
87,5 
87,6 
87,8 


88,3 
88,4 
88,6 
88,8 

89,0 

89,3 
89,4 
89,6 


90,0 

90,2 
90,4 
90,6 
90,8 

91,0 

91,2 
91 '4 
91.6 
91,8 

92,1 

92,2 
93,4 
93,7 
93,8 

93,0 

93,3 
93,4 
93,7 
93=9 
94,0 

94,3 
94.5 
94,7 
94.9 

95,1 
95,3 
95,6 

95,7 
96,0 

96,3 

96,3 
96,6 

96>9 
97.0 

97,3 

97,5 
97.7 
97,8 
98,3 
98,3 
q8,5 


iMg     of 

t'  (Jays. 


0,940 
0,941 
0,942 
0,943 
0,944 

0,945 
0,946] 

o,94' 
0,948 
0,949 

0,950 
0,951 
0,952 
0.953 
0,954 

0,955 
0,956 
0,957 
0,958 
0,959 

0,960 

0,961 

0.96 

0,963 

0,964 

0,965 
0,966 
0,967 
0,968 
0,969 

0,970 
0,971 
0,973 
0,973 
0,974 

0,975 
0,976 

0,97 
0,978 

0,979 

0,980 
0,981 
0,982 
0,983 
0,984 

0,985 
0,986 
0,987 
0,988 
0,989 

0,990 
0,991 
0,992 
0,993 
0,994 

0.995 
0,996 

0,99 
0,998 

0,999 
1,000 


'I'rue 
A  nom.   U< 


I2,o3,Ol,& 

I2,o4,4o,3 
I2,c6,i9,< 
i2,o7,5b,o 
13,09,37,2 

I2.ii,>6,6 
12,12,56,3 
I3,i4,36,i 
12,16,16,3 
12,17,56,4 

12,19,37,0 
12,31,17 

12,22,58,6 

12,34,39,8 
12,26,21,3 

12,28,02,8 
12,29,44,7 
12,31,26,7 
12,33,09,0 
I2,34,5i,5 

13,36,34,3 
12,38,17,3 
12,40,00,4 
12,41,43,8 
12,43,27,5 

12,45,11,3 
12,46,55,4 
1 2^8,39,6 
i3,5o,34,3 
13,53,09,1 

12,53,54,1 
12,55,39,3 
12,57,24,8 
12,59,10,5 
i3,oo,56,4 

l3,02,42,6 

i3,o4,29,o 
1 3,06, 1 5,6 
i3,o8,o2,5 
13,09,49,6 

i3, 1 1,36,9 
i3,r3,24,5 
t3,i5,i2,3 
i3, 17,00,3 
i3,i8,48,6 

i3,20,37,i 
i3, 22, 25,9 
i3,24,i4,8 
i3, 26,04, 1 
13,27,53,5 

13,39,43,2 
i3,3i,33,3 
i3,33,23,3 
i3,35,i3,7 
1 3,37,04,4 

i3,38,55,3 
i3,4o,46,4 
1 3,42,37,8 
13,44,29,4 
13.46.3 1,3 
i3,48,i3,4 


98,5 

98,7 
99,0 

99.2 

99.4 

99.7 
99.8 
100,1 
100,2 

100,6 

100,7 
100,9 
101,2 
101,4 
101,6 
101,9 

103,0 
102,3 
102,5 

102,8 

102,9 

Io3,2 

io3,4 
io3,7 

io3,8 

io4,i 
io4,4 
io4,5 


io5,o 

io5,2 
io5,5 
io5,7 
io5,9 

106,3 

106,4 
106,6 
io6,g 
107,1 

107,3 

107,6 
107,8 
108,0 
108,3 

108,5 

108,8 
108,9 
109,3 
109,4 
109,7 

110,0 
110,1 
110,4 
110,7 

110,9 

111,1 
111,4 
111,6 
111,9 
112,1 
1 12,3 


Log.  >,1 
t'  duys. 


1 ,000 
1,001 
1,002 

i,oo3 
i,oo4 

i,oo5 
1,006 

I,00' 

1,008 
1,009 

1,010 
1,011 

1,013 

1,01 3 
1,014 

1,01 5 

1,016 

1,01 

1,018 

1,019 

1,020 
1,021 
1,022 
1,023 
1,024 

1,025 
1,026 
1,027 
1,038 
1,039 

i,o3o 
i,o3i 

l,o32 

i,o33 
i,o34 

i,o35 
i,o36 
1.037 
i,o38 
1,039 

i,o4o 

1. 04 1 

1. 042 
i,o43 
i,o44 

1,045 
1,046 

I,o47 

i,o48 
1,049 

i,o5o 
i,o5i 

I,o52 

i,o53 
i,o54 

i,o55 
1,0  56 
i,o57 
i,o58 
1,059 
1,060 


True 
Anom.   U. 


tt  m    s 

3,48,i3,4 
3,5o,o5,- 
3,5i,58,3 
3,53,5i,2 
3,55,44,3 

3,57,37,6 
3,5g,3i,2 
4,01,35,0 
4,03,19,1 
4,o5,i3,4 

4,07,07,9 
4,09,02,7 
4,10,57,8 
4,13,53.1 
4,14,48,6 

4,i6,44,4 
4,18,40,5 
4,30,36,8 
4,32,33,4 
4,24,3o,2 

4,26,27,3 
4,28,24,6 

4,3o,23,2 
4,32,20,0 

4,34,18,1 

4,36,16,5 
4,38,i5,i 
4,4o,i3,g 
4,43, i3,o 
4,44,13,4 

4,46,12,0 
4,48,1 1, g 
4,5o,i2,o 
4,52,12,4 
4,54,1 3 

4,56,14,0 
4,58,i5,3 
5,00,16,7 
5,03,18,4 
5,04,20,4 

5,06,22,6 
5,08,25,1 
5,10,27,8 
5,i2,3o,7 
5,14,34,0 

5,16,37,5 
5,18,41,3 
5,20,45,4 

5,22,4g,7 

5,24,54,3 

5,26,59,1 
5,29,04,2 
5,31,09,6 
5,33,15,3 
5,35,21,2 

5,37,27,4 
5,39,33,9 
5, 4 1, 40,7 
5,43,47,7 
5,45,55,0 
5,48,02,6 


Diff. 


3,3 

2,6 

2.9 
3,1 

3,3 

3,6 
3,8 
4,1 
4,3 

4,5 

4,8 
5,1 
5,3 
5,5 

5,8 

6.1 
6;3 
6,6 
6,8 

7>i 

7.3 
7,6 
7,8 
8,1 

8,4 

8,6 
8,8 

9.1 
9.4 

9.6 

9.9 
20,1 

30,4 
30,7 


21,2 
21,5 
31,7 
22,0 

22,3 

22,5 
23,7 
23,9 
33,3 

33,5 

23,8 
24,1 

34,3 
24,6 

24,8 

25,1 

25,4 
25,7 

25,9 

26,2 

26,5 
26,8 

27,0 

27,3 

27,6 

37,8 


Log.  of 
V  days. 

1,060 
1,061 
1,062 
1  ,o63 
1,064 

i,o65 

1,066 

i,o& 

1,068 

1,069 

1,070 
1,071 
1,073 
1,073 
1,074 

1,075 
1,076 

1.077 
1,078 
1,079 

1,080 
1,081 
1,083 
i,o83 
1,084 

i,o85 
1,086 
1,087 
1,088 
1,089 

i,ogo 
1,091 
1,093 
i,og3 
1,094 

I,og5 
1,096 
1,097 
1,098 
1.099 

1,100 
1,101 
1,102 
i,io3 
i,io4 

i,io5 
1,106 
1,107 
i,io8 
I, log 

1,110 
1,111 

1,113 

i,ii3 
i,ii4 

i,ii5 
1,116 
1,117 
1,118 
1,119 
1,120 


True 
Anum.  U. 


5,48,02,6 
5,5o,io,4 
5,52,18,5 
5,54,26.9 
5,56,35,5 

5,58,44,4 
6,00,53,6 
6,o3,o3,o 
6,o5,i2,8 
6,07,22,8 

6,09,33,1 
6,11,43,7 
6,i3,54,6 
6,i6,o5,7 
6,18,17,1 

6,30,38,8 
6,22,40,8 
6,24,53,1 
6,27,05,6 
6,29,18,5 

6.3 1.3 1.6 
6,33,44,9 
6,35,58.6 
6,38,12,5 
6,40,26,7 

6,43.41.3 
6,44;55;9 
6,47,11,1 
6,49,26,5 
6,5i,42,i 

6.53,58.0 
6,56,14.3 
6,58,30,8 
7,00,47,6 
7,o3,o4,6 

7,05,22,0 
7.07,39,7 
7,09,57,7 
7,12, i5,c) 
7.14.34,4 

7,16,53,2 
7,19,13,3 

7.3 1.3 1. 7 
7,33,5i,4 
7,36,11,4 

7,28,31,7 
7,3o,52,3 
7,33,i3,i 
7,35.34,3 
7,37,55,8 

7,40,17,6 
7,42,39,6 
7,45,01,9 
7,47,24,6 
7,49,47.5 

7,53,10,8 
7,54,34,3 
7,56,58,1 
7,59,22,3 
8,01,46,7 
8,04,11,5 


Diff. 


37,8 
28,1 
28,4 
28,6 

28,9 

39.2 
29,4 
29.8 
3o,o 

3o,3 

3o,6 
3o,g 
3i,i 
3i,4 

3i,7 

32,0 
33,3 
32,5 
32,9 

33,1 

33,3 
33,7 
33,9 
34,2 

34,5 

34,7 
35,2 
35,4 
35,6 

35,9 
36,3 
36,5 
36,8 
37,0 

37.4 

37.7 
38.0 
38,3 
38,5 

38,8 

39,1 
3g,4 
39:7 
40,0 

40,3 

40,6 
40,8 

4l,2 

4i,5 

4i,8 

42,0 
43,3 
43,7 
42,9 

43,3 

43,5 
43,8 
44,3 
44.4 
44,8 
45,0 


Log.  ol 
('  day.s 


1,130 

J, I 
1,122 
1,123 
1,124 

1,125 
1,126 
1,127 
1,128 
1.129 

i,i3o 
i,i3i 

l,l33 

i,i33 
i,i34 

i,i35 
I, I 

i,i37 
1,1 38 
i,i39 


i,i4i 
1,1 
1,143 
i,i44 

1, 145 
i,i46 
i,i47 
i,i48 
1,149 

i,i5o 
i,i5i 

I,l52 

i,i53 
1,1 54 

i,i55 
1,1 56 
i,i57 
1,1 58 
1,159 

1,160 
1,161 
1,163 
i,i63 
1,164 

i,i65 
1,166 
1,167 
1,168 
1,169 

1,170 
1,171 
1,173 
1,173 
1,174 

1,175 
1,176 
1,177 
1,178 
1,170 
I,ll 


True 
Anom.    U, 


8,04,11,5 

8,o6,36,5 
8, eg  ,01 ,9 
8,1 1,37,5 
8,13,53,5 

8,16,19,7 

8,18,46,3 
8,31, i3. 1 
8,33,40,3 
8,26,07,8 

8,38,35,5 
8,3i,o3,6 
8,33,32,0 
8,36,00,7 
8,38,29,7 

8,40,59,0 
8,43,28,6 
8,45,58,5 
8,48,38,8 
8,50,59,3 

8.53,3o,2 
8,56,01,4 
8,58,32,8 
g,oi,o4,6 
g,o3,36,7 

9.06,09,1 
9,08,41,8 
9,11,14,8 
g,i3,48,2 
9, 16,3 1, g 

9,18,55,9 
9,21,30,2 
9,24,04,8 
9,36,3g,8 
9.29.15.0 

9,3i,5o,6 
9,34,36,5 
9,37,02,7 
9,39,39,3 
9,43,16,0 

9,44,53,3 
9,47,3o,8 
g,5o,o8,7 
g,52,46,g 
g,55,25,3 

ig,58,o4,i 
20,00,43,2 

2O,03,22,6 

30,06,02,3 
20,08,42,4 

20,1  1,23,1 

2o,i4,o3,5 
20,16,44,5 
20,19,35,9 
20,33,07,6 

20,34,49,6 
30,27,32,0 
2o,3o,i4,7 
20,32,57,7 
2o,35,4i,o 
20,38,24,7 


Diff. 


45,0 
45,4 
45,6 
46,0 

46,3 

46,6 
46,8 

47,3 
47.5 

47.7 
48,1 
48,4 
48,7 
49,0 

49,3 

49,6 
49.9 
5o,3 
5o,5 

5o,g 

5l,2 

5i,4 
5i,8 

52 

52,4 

52,7 
53,0 
53,4 
53,7 
54,0 

54,3 
54,6 
55,0 
55,2 

55,6 

55,9 
56,2 
56,5 
56,8 

57,3 

57,6 

57,9 
58,3 
58,4 

58,8 

5g,i 
59,4 
59.7 
60,1 

60,4 

60,7 
61,0 
61,4 
61,7 

63,0 

63,4 
63,7 
63 ,0 
63,3 

63,7 
64,0 


TABLE   IJI. 

To  find  the   true  anomaly   U,  corresponding  to  the  time  f  from  the  perihelion  in  days,  in  a  paraholic  orbit,  whose  perihelion 
distance  is  the  same  as  tlie  mean  distance  of  the  sun  from  the  earth. 


Log.  of 
t'  days. 


i,i8o 
i,i8i 
1,182 
i,i83 
1, 184 

i,i85 
1,186 
1,187 
1,188 
i,ie 

1,190 
1,191 
1,192 
1,193 
1. 194 

1,195 
1,196 

1. 197 
1,198 

1. 199 

1,200 
1,201 
1,202 

I,203 

1,204 

I,2o5 

1,206 
1,207 

1,20 
1,209 

1,210 
1,211 
1,212 
1,2 1 3 
I,2l4 

1,2  1 5 
1,216 
1,217 
1,218 
I.2I9 

1,220 
1,221 
1,222 
1,223 
1,224 

1,225 
1,226 
1,227 
1,22 


Truo 
Anom.  U. 


1,22g 

1,280 

1,23 1 

1,232 

1,233 

1,234 

1,235 

1,236 

1,237 

1,238 

1,239 

1,240 

20,38,24,7 
20,4i,o8,7 
20,43,53,0 
20,46,37,6 
20,49,22,6 

20,52,07,9 
20,54,53,6 
20,57,39,6 
21,00,25,9 

2I,03,I2,6 

21,05,59,6 
21,08,46,9 
21,11,34,6 

21, r4, 22,6 

21,17,10,9 
21,19,59,6 

21,22,48,6 

21,25,37,9 
21,28,27,6 
2i,3i,i7,6 

21,34,08,0 
21,36,58,7 
21,39,49,7 
21,42,41,1 
21,45,32,8 

21,48,24,8 

2I,5l,17,2 

21,54,10,0 
2i,57,o3,i 
21,59,56,6 

22,03,5o,4 

22,o5,44,5 
22,08,39,0 
22,11,33,8 

22,14,29,0 

32,17,24,5 
22,20,20,3 
22,23,16,5 

22,2D,l3,0 
22,29,09,9 

22,32,07,1 
22,35,04,7 
22,38,02,6 
22,4l,00,9 

22,43,59,5 

22,46,58,5 
22,4g,57,8 
22,52,57,4 
22,55,57,4 
22,58,57,8 

23,01,58,5 
23,04,59,6 
23,08,01,0 

23,11,02,7 

23,i4,o4,8 

23,17,07,3 
23,20,10,1 
23,23, i3,3 
23,26,16,8 
23,29,20,7 
33,32,24,9 


i64,o 
i64,3 
i64,6 
i65,o 

i65,3 

i65,7 
166,0 
166,3 
166,7 

167,0 

167,3 

167,7 
168,0 
168,3 

168,7 

169,0 
169,3 
169,7 
170,0 

170,4 

170.7 
171,0 

171.4 
171.7 
172,0 

172.4 
173,8 
173.. 
173,5 

173,8 

174.1 
174,5 
174 
175,3 

175,5 

175,8 
176,2 
176,5 
176,9 

177,2 

177,6 

177,9 
178,3 
178,6 

179,0 
179,3 
179,6 
180,0 
180,4 

180,7 

181 
181,4 
181.7 
182,1 

182,5 

183,8 
i83.2 
i83,5 
i83,9 
1 34.2 
184,6 


Log.  ol 
V  days. 


True 
Anora.  U. 


1,240 
1,24 1 
1,242 
1,243 
1,244 

1,245 
1,246 
1,247 
1,248 
1,249 

I,25o 
I,25l 
1,252 

1,253 
1,254 

1,255 
1,256 
1,257 
1,258 
1,359 

1,260 
1,261 
1,262 
1,263 
1,354 

1,265 
1,366 
1,267 
1,368 
1,269 

1,2' 

1,371 

1,373 

1,373 

1,274 

1,275 
1,276 

1,277 
1,278 

1,279 

1.280] 
1,281 
1.282 

1^283 
1,384 

1,285 

1,286 

1,287 

1,2 

1,289 

1,290 
1,291 
1,292 
1,293 
1,294 

1,395 
1,296 
1,29- 


1,299 
1 ,3oo 


d    m      s 
23,33,24,9 
33,35,29,5 

23,38,34,5 
23,41,39,8 

23,47,5i,4 
23,50,57,8 
23,54,04,5 
23,57,11,6 
24.00,19,0 

24,03,26,8 
24,06,35,0 
24,09,43,5 

24,13,52,4 

34,16,01,6 
24,19,11,2 

24,22,31,2 
34,25,3l,5 
24,28,42,2 

24,3i,53,3 

24,35,04,7 
24,38,16,5 
24.41,28,6 
34,44.41,1 
24,47,54,0 

34,51,07,3 
24,54,20,9 
24,57,34,9 
25,00,49,2 
25,o4,o3,9 

25,07,19,0 
25,10,34,4 
25,i3,5o,3 
25,17,06,4 
25,20,23,0 

25,23,39,9 
25,26,57,2 
25,3o,i4,g 
25,33,32,9 
25,36,5i,3 

25,4o,io,i 
25,43,39,3 
25,46,48,8 
25,5o,o8,7 
25,53,29,0 

25,56,49,6 
26,00,10,6 
26,03,32,0 
36,06,53,8 
2D,io,i5,9 

36,i3,38,5 
26,17,01,4 
26,30,34,7 
26,23,48,4 
26,27,12,4 

36,3o,36,8 
26,34,01,6 
26,37,26,7 
26,40,52,3 
36,44,18,3 
36,47,44,5 


Diff. 


i84,6 
i85,o 
i85,3 
1 85,6 

186,0 

186.4 
186,7 
187,1 
187,4 

187,8 

188,3 
188,5 
188,9 
189,2 

189,6 

190,0 
190,3 
190,7 
191,1 

191,4 

191,8 
192,1 
192,5 
'92,9 
193,3 

193,6 
194,0 
194,3 
194,7 
195,1 

195,4 
195,8 
196,2 
196,6 

196,9 
197,3 

197.7 
198,0 
198,4 
198,8 

199,2 
199,5 
199,9 
200,3 

200,6 

201,0 
201,4 
201,8 
202,1 

202,6 

203,9 
2o3,3 
2o3,7 
204,0 

2o4,4 

2o4,8 
2o5,i 
2o5,6 
2o5,9 
206,3 
206,6 


Log.  of 
t'  days. 


I,3oo 
i,3oi 

I,303 

i,3o3 
i,3o4 

i,3o5 
i,3o6 
1 ,307 
i,3o8 
1,809 

i,3io 
i,3ii 

I,3l2 

i,3i3 
i,3i4 

i,3i5 
i,3i6 
1,817 
1,818 
1,819 

1,820 

1,331 

1,833 
1,333 
1,324 

1,325 
1,336 
1,337 
1,328 
1,339 

i,33o 
1,33 1 
1,333 
1,333 
1,334 

1,335 
1,336 
1,337 
1,838 
1,339 

1,340 
1,341 
1,343 
1,343 
1,344 

1,345 
1,846 
1,347 
1,348 
I,- 

i,35o 
i,35i 
1,353 
1,353 
1,354 

1,355 

1,356 

1,35 

1,358 

1,359 

i,36o 


True 
Anom.  U. 


26,47,44,5 
26,51,11,1 
26,54,38,1 
26,58,o5,5 
27,01,33,3 

27,05,01,4 
27,08,29,9 
27,11,58,8 
27,15,38,1 
27,18,57,8 

27,23,37,8 
27,35,58,3 
27,29,29,0 
27,88,00,2 
27,86,81,9 

27,4o,o3,S 
27,43,86,1 
27,47,08,8 
27,50,4 1, g 
27,54,15,4 

27,57,49,3 
38,01,28,5 
38,04,58,1 
28,08,33,1 
28,12,08,5 

28,15,44,2 
28,19,20,3 
28,23,56,9 
28,36,88,8 
28,80,11,1 

28,33,48,7 
28,87,26,8 
28,41,05,3 
28,44,44,1 
28,48,28,3 

28,52,02,9 
28,55,42,9 
28,59,28,3 
2g,o3,o4,o 
29,06,45,2 

39,10,26,7 
29,14,08,6 
39,17,50,9 
29,31,33,6 
29,25,16,7 

29,29,00,2 
29,82,44,0 
29,86,38,8 
29,40,13,9 
29,48,57,9 

39,47,43,3 
29,51,29,1 
39,55,15,3 
29,59,01,8 
3o,o2,48,8 

3o,o6,36,i 
30,10,38,9 
3o,i4,i3,o 
80,18,00,5 
80,31,49,4 
3o,35,38,7 


Log,  of 

t'  diiys. 


3o6,6 
207,0 
207,4 
307,8 

208,1 

208,5 
208,9 
209,3 
209,7 

210,0 

210,4 
210,8 

311,2 
211,7 
211,9 

212,3 
212,7 
2l3,l 
21 3,5 

218,9 

2l4,2 

2i4,6 

21 5,0 

2 1 5,4 

21 5,7 

216,1 
216,6 
216,9 
217,8 

217,6 

218,1 
218,5 
218,8 
219,2 

21 9,6 

230,0 

220,4 

220,7 

331,2 

221,5 

221,9 
222,3 
222,7 
228,1 

228,5 

233,8 
234,3 
334,6 
235,0 

225,4 

335,8 

226,2 
336,5 
227,0 

227,3 

227,8 

228,1 

228,5 

338,g 
22g,3 

32Q, 


True 
Anom.    U. 


1 ,860 

1,36 1 
1,363 
1,863 
1,364 

1,365 
1,366 
1,867 
1,368 
i,36g 

1,870 
1,371 
1,873 
1,878 
1,874 

1,375 
1,876 

1,377 
1,378 

1,379 

i,38o 
i,38i 
1,382 
1.388 
1,384 

1,385 
1,386 
1,887 
1,888 
1,389 

1 ,890 
1,891 
1,892 
1,393 
1,394 

1,895 
1,396 
i,3g7 
1,898 
1 ,399 

i,4oo 
1,401 
1,402 
i,4o3 
i,4o4 

i,4o5 
i,4o6 
1,407 
i,4o8 
i;4og 

i,4io 
i,4i 

I,4l2 

i,4i3 
i,4i4 

i,4i5 

i,4i6 

1,417 

i,4i 

1.419 

1,420 


Diff. 


3o,35,38,7 
80,39,28,4 
80,33,18,5 
80,87,08,9 
80,40,59,8 

3o,44,5i,o 
80,48,42,7 
80,52,34,7 
80,56,27,1 
31,00,19,9 

3i,o4,i3,i 
81,08,06,7 
81,12,00,7 
3i,i5,55,i 
31,19,49,8 

81,28,45,0 
81,37,40,5 
8i,3i,36,5 
81,35,82,8 
81,39,29,5 

3  [,43,36,6 
81,47,34,1 

3l,5l,32,0 

81,55,20,3 
81,59,19,0 

32,o3,i8,o 
32,07,17,5 
82,1 1,17,3 
83,15,17,5 
32,19,18,2 

82,28,19,2 
82,27,20,6 
82,81,22,4 
82,35,24,6 
83,89,37,3 

33,43,80,1 
82,47,33,5 
82,51,87,3 
83,55,41,4 
33,59,46,0 

38,o3,5o,9 
33,07,56,3 
88,13,02,0 
33,16,08,1 
33,20,14,6 

33,24,21,5 
33,38,38,7 
33,33,36,4 
33,36,44,5 
33,40,52,9 

88,45,01,8 
88,49,11,0 
83,53,20,7 
88,57,80,7 
34,01,41,1 

84,o5,5i,9 
84,10,08,1 
34.14,14,7 
84,18,26,6 
34,22,89,0 
84,26,51,8 


Log.  of 
('  du 


339,7 
280,1 
280,4 

23o,9 

23l,3 

281,7 
282,0 
282,4 

233,8 
283,3 

333,6 
334,0 
334,4 
234,7 

235,2 

235,5 
286,0 
286,8 
236,7 

287,1 

287,5 
287,9 
238,3 
288,7 

289,0 

289,5 
289,8 
240,2 
240,7 

241,0 

241,4 
241,8 
242,2 
243,6 

242,9 

243,4 
243,8 
244,1 
244,6 

244,9 

245,3 
245,8 
246,1 
246,5 

246,9 
247,2 
347,7 

348,1 

248,4 
248,9 
249,3 

249,7 
25o,o 
25o,4 

25o,8 

25l,3 

3  5 1, 6 
i5i,9 

253,4 
2  53,8 

253,1 


1,420 
1,421 
1,422 

1^438 
1,424 

1,425 

1,426 

1,427 

1,428 

1,439 

1,480 
i,43i 
1,482 
1,433 
1,434 

1,435 
1,436 
1,437 
1,438 
1,439 


True 
Anom,  U. 


34,36,5 1,8 
34,81,04,9 
34,35,18  " 
34,89,82,4 
34,43,46,7 

34,48,01,4 
84,52,16,5 
84,56,83,0 
85,00,47,8 
35,o5,o4,i 

35,09,20,7 
35,18,37,7 
35,17,55,3 
35,33,18,0 
35,26,81,2 

35,80,49,7 

35,85,08,7 

35,3g,2i 

85,43,47,8 

35,48,08,0 


i,44o   35,52,28,5 
i,44i    35,56,49,4 


1,442 
1,443 
1,444 

1,445 
1,446 
1,447 
1,448 


i,45o 
1,45: 
1,452 
1,453 
1,454 

1,455 
1,456 
1,457 
1,458 
1,459 

1,460 
1,461 
1,462 
1,468 
1,464 

1,465 
1,466 
1,467 
1,468 
1,469 

1,470 
1,471 
1,472 
1,473 
1,474 

1,475 
1,476 
1,477 
1,478 

1,479 
1,480 


36,01,10,7 
86,05,82,4 
86,09,54,4 

36, 1 4, 1 6,9 
86,18,89,8 
86,33,08,0 
86,27,36,6 
36,3i,5o,6 

36,36,15,0 
36,40,89,8 
86,45,04,9 
86,4o,8o,5 
86,53,56,4 

36,58,22,7 
87,02,49,4 
87,07,16,5 
87,11,43,9 
87,16,11,8 

87,20,40,0 
87,25,08,6 
87,39,37,6 
87,84,07,0 
87,88,86,7 

87,43,06,9 
87,47,37.4 
87,52,08,3 
87,56,39,6 
38,01,11,3 

88,o5,43,3 
38,io,i5,7 
38, 14,48,5 
88,19,21,7 
38,23,55,3 

88,38,29,3 
38,38,o3,5 
88,87,88,3 
88,43,18,2 
38,46,48,7 
88,5i,24,5 


253,1 
353,6 
253,9 
354,3 

254,7 
255,1 
255,5 
355,8 
3  56,3 

356,6 

357,0 
357,5 
257,8 

258,2 

258,5 

259,0 
259,4 
359,7 
360,2 

260,5 

260,9 
261,8 
261 
262,0 

262,5 

262,9 
268,2 
363,6 
264,0 

364,4 

264,8 
265,1 
265,6 
265,9 

266,3 

266,7 
267,1 
367,4 
267,9 

368,2 

268,6 

369,0 
369,4 
269,7 

270,2 

270,5 
270,9 
371,3 

271,7 

273,0 

272,4 
272,8 
278,2 

378,6 
273,9 
274,3 
274,7 

375,0 

375,5 
275,8 

276,1 


TABLE    III. 


To  fin 
distance 


1  tlie  true  anonuily 
is  the  same  as  tlie 


V,  corresponiliiig  to  llie  time  ('  from  the 
iiiCiHi  ilislrtiice  ol  tlie  sim  from  the  earth. 


perihelion  in  days,  in  a  parabolic  orbit,  whose  perihelion 


Log.  I.I 
I'  duvs 


True 
.-\iiom.  U. 


l,4So 

i,48i 
1,485 
1,483 
1,484 

1,485 

1,466 

1,48' 

1,481 

1,489 

1,490 
1.491 
1,492 
1,493 
1.494 

1,495 
1,496 
1,497 
1,498 
1.499 

i,5oo 

i.5oi 
i,5o3 
i,5o3 
i,5o4 

i,5o5 
i,5o6 

I,507 

i,5o8 
1,509 

i,5io 
i,5i  I 

I,5l3 

i,5i3 
i,5i4 

i,5i5 
i,5i6 
I,5i7 
I,5i8 
1,519 

1,530 
1,52  1 
1,522 

1,523 

1,524 

1,525 

1,526 

1,527 

1,528 

1,529 

i,53o 
1,53 1 
1,532 
1,533 
1,534 

1,535 
1,536 
1,537 
1,538 
i,53q 
i,54n 


38,5 1, 24,5 
38,56,00,6 
39,00,37,3 
39,o5,i4,i 
39,09,51,4 

39,14,29,1 
39,19,07,1 
3g,23,45,5 
39,28,24,3 
39,33,03,5 

39,37,43,0 
39-42,33,9 
39,47,03,3 
39,51,43,8 
39,56,24,8 

40,01,06,2 
4o,o5,48,o 
4o,io,3o,i 

4o,l5,!3,6 

40,19,55,4 
40,34,38,6 

4o,2g,22,2 

40,34,06,2 
4o,38,5o,5 
40,43,35,2 

40,48,20,2 
4o,53,o5,6 
40,57,5 1,4 
41,02,37,6 
41,07,24,1 

41,12,10,9 

4i,i6,58, 

41,21,45,7 

41,26,33,6 

4i,3i,2i,9 

4i, 36, 10,6 
41,40,59,6 
41,45,49,0 
4i,5o,38,7 
4i,55;:S,8 

42,00,19,2 
42,o5,io,o 
42,10,01,1 
43,14,52,6 
42,19,44,4 

43,24,36,6 
43,39,39,2 
42,34,22,1 
43,39,15,3 
42,44,08,9 

43,49.02,9 
42,53,57,2 
42, 58,5 1, 9 
43,03,46,9 
43,08,42,3 

43,i3,38,o 
43,18,34,0 
43,33,304 
43.38,27,1 
43,33,24,3 
43,38,2 


Uiff. 


276,1 
376,6 

276,9 
277,3 

277,7 
278,0 
278,4 
278,8 
279,2 

279,5 

279-9 
280,3 
380,6 
281,0 

281,4 

381,8 
282,1 
283,5 
382,8 

383,2 

283,6 
284,0 
284,3 
284,7 
285,0 

285,4 
285,8 
286,3 
286,5 

286,8 

287,2 
287,6 
287,9 
288,3 

288,7 

289,0 
289,4 
289,7 
290,1 

290,4 

290,8 
291,1 
391,5 
291.8 

292,3 

293,6 

292,9 
293,3 
293,6 

294,0 

294,3 

294,7 
395,0 
295,4 

295,7 

296,0 
296,4 
296,7 

297-1 
297,5 


U,g.  of 
('  tlujs. 


,540 
,541 
,543 
,543 
,544 

,545 
,546 

,547 

,548 
,549 

,55o 
,55i 
,552 
,553 
,554 

,555 
,556 
,557 
,558 
.559 

,56o 
,56i 
,562 
,563 
,564 

,565 
,566 
,567 
.568 
,569 

,570 
,571 
,572 
.573 
,574 

,575 
,576 
,577 
,578 
,570 

,5So 
,58 1 
,582 
,583 
,584 

,585 
,586 
,587 
,588 
,589 

,590 
,591 
,592 
,593 
,594 

,595 
,596 
,597 
,598 

,599 
,600 


True 
Aiiom.  U. 


43,38,31,7 
43,43,19,5 
43,48,17,5 
43,53,1 5,8 
43,58,i4,5 

44,o3,i3,6 
44,08,1 3,0 
44, i3,i2,7 
44,18.13,8 
44. 23,i3,2 

44,28,14,1 
44,33, i5, 3 
44,38, 16,6 
44,43,18,4 
44,48,20,5 

44,53,22,9 
44,58,35,7 
45,03,38,8 
45,08,33,2 
45,1 3,36,0 

45,i8,4o,i 
45,33,44,6 
45,38,49,4 
45,33,54,5 
45,38,59,9 

45,44,05,6 
45,49,11,7 
45,54,18,0 
45,59,34,7 
46,o4,3i,7 

46,09,39,0 
46,14,46,6 
46,rg,54,6 
46,35,03,9 
46,3o,ii,5 

46,35,20,3 
46,40,39,5 
46,45,39,0 
46,5o,48,8 
46,55,59,0 

47,01,09,4 
47,06,20,1 

47,1 1,3l,2 

47,16.42,6 
47,21,54,3 

47,27,06,3 
47,32,18,6 
47,37,31,2 
47,42,44,1 
47.47,57,2 

47,53,10,7 
47,58,24.5 
48,o3.38,6 
48,08,52,9 
48.14,07,6 

48,19,32.6 
48,24,37.9 
48,39,53,^ 
48,35.09.3 
48  4o,35..< 
48,4  5,4 1, t 

a21 


297,8 
298,0 
298,3 
298,7 

299,' 

299-4 
299-7 
3oo,i 
3oo,4 
3oo,g 

3oi,i 
3o  1 ,4 
3oi,8 
3o2,i 

3o2,4 

3o3,8 
3o3,i 
3o3,4 
3o3,8 

3o4,2 

3o4,4 
3o4,8 
3o5,i 
3o5,4 
3o5,7 

3o6,i 
3o6,3 
3o6,7 
307,0 

3o7,3 

3o7,6 
3o8.o 
3o8.3 
3o8,6 

3o8,8 

309,3 
309,5 
309,8 

3lO,3 

3io,4 

3 1 0,7 
3ii,i 
3u,4 
3ii,7 

3l3,0 

3i3,3 
3 1 3,6 
3i2,9 
3i3,i 

3i3,5 

3i3,8 
3i4.i 
3i4,3 
3i4,7 
3t5,o 

3i5,3 
3i5,5 
3i5.g 
3i6.i 
3 1 6,5 
3i6.7 


Log.  01" 
('  days. 


1,600 
1,601 
1,602 
1 ,6o3 
i,6o4 

i,6o5 
1,606 
1,607 
1,606 
1,609 

1,610 
1,611 
1,612 
i,6i3 
i,6i4 

i,6i5 
1,616 
1,617 
i,6iS 
1.619 

1,620 
1,621 
1,622 
1,623 
1.624 

1,635 
7,636 
1,637 
1,638 
1,639 

i,63o 
1,63 1 
1,632 
1,633 
1,634 

1,635 
1,636 
1,637 
1,638 
1,639 

1,640 
i,64i 
1 ,642 
1,643 
1,644 

1,645 
1,646 
1,647 
1,648 
1,649 

i,65o 
J, 65 1 
1,652 
1,653 
1,654 

1,655 
1 ,656 
1,657 
1,658 
1  -659 
1,660 


'i'rue 
Anoni.  U, 


48,45,41,9 
48,5o,58,6 
48,56,1 5,6 
49,0 1, 32, g 
49,06,50,4 

49,12,08,3 
49,17,36,5 
49,33,44,g 
49,28,03,6 
49,33,33,6 

49,38,41,8 
4g,44,oi  ,4 
4g.4g,3i,3 
49,54,41,3 
5o,oo,oi,7 

5o,o5,23,3 
5o, 10,43, 3 
5o,i6,o4,4 
5o, 31, 35,9 
50,36,47,6 

50,32,09,6 
5o,37,3i,8 
50,43,54,3 
5o,48,i7,i 
5o,53,4o,2 

5o, 59,03, 5 
51,04,27, 1 
5i,og,5o,9 
5i,i5,i5,o 
51,20,39,4 

5i  ,26,04,0 
5i, 31,28,9 
5 1, 36,54,0 
51,42,19,4 

5 1. 47.45.0 

5i,53,io,Q 
51,58,37,0 
52,o4,o3,4 
52,09,30,0 
52,i4,56,9 

52,20,34,0 
53,35, 5i,3 
53.3i,r8,9 
52,36,46,7 
52,42,14,8 

52,47,43,1 
52,53,11,6 
53,58,4o,4 
53,o4,og,4 
53,og,38,7 

53,i5,o8,2 
53,20,37,9 
53,26,07,9 

53.31.38. 1 
53,37,08,5 

53,42,39. 

53,48,09.9 

53,53.41,0 

53.59  13,3 

54,04,43,9 

54,io,i5,6 


DifT, 


3 1 6,7 
3i7,o 
3i7,3 
3i7,5 

3i7,9 
3i8,2 
3 18.4 
3i8;7 
319,0 

319,3 

319,6 
3,g,8 
320,1 

320,4 
320,6 
32o,g 

321,3 

331,5 
321,7 
333,0 

323,3 
323,5 
323,8 

323,1 

323,3 

323,6 
323,8 
324,1 
324,4 

324,6 

324,g 
325,1 
325,4 
325,6 

325,g 

326,1 
326,4 
336,6 
326,9 

327,1 

327.3 
337,6 
337,8 
328,1 

338,3 

338,5 
338,8 
339,0 
329,3 

32g,5 

33g,7 
33o,o 
33o,3 
33o,4 

33o,6 

33o.8 
33i.i 
33 1, 3 
331.6 
33 1, 7 
33t,q 


f  days 


,660 
,661 
.663 
,663 
,664 

.665 
,666 
,667 
,668 
,66g 

,670 
.671 

;673 

,673 
,674 

.675 
,676 

,677 

,678 

,679 

,680 
,681 
.682 

,683 
,684 

,685 
,686 
,68-j 
,688 
,689 

,690 
,6gi 
,6g2 
.693 
,694 

,695 
,696 

,697 
,6g8 

.699 

,700 
,7UI 
,702 
,703 
,704 

,705 
,706 

,707 
,708 

,709 

,710 

f7ii 
,712 
,71 3 
,7 '4 

,71 5 
,716 

^717 
,718 

-719 


Tiuo 
Anom.  U. 


d     m    s 

54,io,i5,6 
54,15,47,5 
54,21,19,7 
54,26,53,1 
54,32,24,7 

54.37,57,5 
54,43,3o,5 
54,4g,o3,7 
54,54,37,1 
55,00,10,8 

55,o5,44,7 
55,11,18,8 
55,16,53,0 
55,23,27,5 
55,28,02,2 

55^3,37,7 
55, 3g, J  3,3 
55,44,47^4 
55,5o,23,g 
55,55,58,6 

56,01,34,4 
56,07,10,4 
56,13.46.7 
56,18,33,1 
56,33,5g,7 

56,39,36.5 
56;35,i3,5 
56,4o,5o,6 
56,46,37,9 
56,53,o5,4 

56,57,43,3 
57,o3,3r,i 
57,08,59,1 
57,14,37,3 
57,20,15,7 

57,35,54,3 
57, 3 1, 33,0 

57,37,11,9 
57,42,50.9 
57,48,3o,i 

57,54,09,5 
57,59,49,2 
58,05,29,0 
58, 1 1, 08 ,9 
58,i6,4g,o 

58,23,39,2 
58,38.09,6 
58.33;5o.i 
58,39,3o,8 
58,45,11,6 

58,5o,52,5 
58,56,33,6 
5g,02,i4,9 
5g,07,56,3 
59,-i  3,37,9 

59,19,19,7 
5g. 25,01, 6 
5g,3o,43,6 
59,36,35.7 
5g,42,o8,o 
59.47,50,4' 


33 1,9 

332,2 

332,4 
333,6 

333,8 

333,0 
333,3 
333,4 
333,7 

333,g 

334.1 
334.3 
334,5 
334,7 

334,g 

335,1 
335,3 
335,5 
335,7 

335,8 

336.0 
336,3 
336.4 
336,6 

336,8 

337,0 
337.1 
3373 
337,5 

337,8 

337,g 
338.0 
338,3 
338,4 

338.6 

338,7 
338,9 
339,0 
339,3 

339,4 

33g,7 
33g,8 
339,9 
340,1 

340,3 

34o,4 
340.5 
340,7 
340,8 

340,9 

341,1 
341,3 
341,4 
341,6 

34 1. 8 

34 1. 9 
343,0 
343,1 
343,3 
343.4 
343.5 


Log.  of 
1/  «lays 


,720 
,73  1 
,723 
,723 
,724 

.735 

;736 

,727 

.72- 

,72g 

.730 

,73, 

,733 

,733 
,734 

,735 

,736 

,737 
,738 

,73g 

,740 
,74 1 
.743 
,743 
,744 

,745 

,746 

•74' 

,748 

,749 

,750 

;75i 

.753 

;753 
,754 

,755 

,756 
,757 
,758 

,759 

,760 
,761 
,763 
,763 
,764 

,765 
.766 
.767 
,768 
,769 

,770 

,771 

:772 
,773 
,774 

,775 
,776 

,777 
,778 
,779 
,780 


Truo 
.^nuiii.  U. 


59,47,50,4 
59,53,33,9 

59,5g,i5,6 
6o,o4,58,4 
60,10,4 

60,16,24,4 
60,33,07,6 
6o,37,5o,g 
60,33,34,3 
60,39,17,8 

60,45,01,5 
6o,5o,45,3 
60,56,29,3 

6l,03,l3,3 

61,07,57,4 

6i,i3,4i,7 
61,19,26,1 
61, 35, 10,6 
6i,3o,55,3 
6i,36,3g,9 

61,42, 34,i 
61 ,48,09,8 
61,53,54,9 
6i,5g,4o,i 
63,o5,35,3 

63,11,10,6 
62,16,56,0 
63,33,41,5 
63,38,37,1 
63,34,12,8 

62,3g,58,6 
62,45,44,5 
62,5i,3o,5 
63,57,16,6 
63,o3,03,8 

63,o8,4g.o 
63,14,35,3 
63,30,31,7 
63.36,08.3 
63,3i,54,8 

63,37 ,4i, 4 
63,43,38,1 
63,4q,i4:9 
63,55,01,8 
64,00,48,7 

64,06,35,7 

64,13,33,8 

64,i8,og,g 
64,33,57,1 
64,3g,44,4 

64.35.3 1. 8 
64,4i,ig,3 
64,47,06,7 
64.53,54,3 
64,58,41,7 

65,o4,3g,3 

65. 10.16.9 
65,i6,o4,6 
65,31,53,4 
65,37.40.3 
65,33,28' 


1 


343,5 
342,7 
342,8 
342,9 

343,1 

343,2 
343,3 
343,4 
343,5 

343,7 

343,8 
343. g 
344io 
344,2 

344,3 

344,4 
344,5 
344,6 
344,7 
344,9 

345,0 
345,1 
345,2 
345,2 

345,3 

345,4 
345.5 
345.6 
345,7 

345,8 

345.9 
346,0 
346,1 
346,2 

346,2 

346,3 
346,4 
346,5 
346,6 

346,6 

346,7 
346,8 
346.9 
346^9 

347,0 

347,1 
347,1 
347,2 
347,3 

347,4 

347,4 
347,5 
347,5 
347,5 

347,6 

347,6 
347,7 
347,8 
347,8 
347,9 
347,9 


To  find  the  true 
distance  is  the  same 


TABLE   III. 

anomaly   U,  coiTCsponding  to  the  time  ('  from  the  perihelion  in 
as  the  mean  dislance  of  tlie  sun  from  the  eajth. 


days,  in  a  parabolic  orbit,  whose  perihelion 


Log.  of 
('  days. 


1.780 
1,781 
1,782 
1,783 
1,784 

1,785 
1,786 

1,787 
1,768 
1,789 

1,7911 
1,791 
1,792 
1,793 

1,794 

1,795 
1,796 

',797 
1,798 

1.799 

1,800 
1,801 
1,802 
i,8o3 
i,8o4 

i,8o5 
1,806 
1,807 
1,808 
i.E 

i,8io 

1,812 

i,8i3 
i,8r4 

i,8i5 
i,8i6 
1,817 
1,818 
1,819 

1,820 
1,821 
1,822 
1,823 
1.824 

1,825 
1,826 
1,827 
1,828 
1,829 

i,83o 
1, 83 1 
1,832 
1,833 
1,834 


True 
Anom.   U. 


65,33,28,1 
65,39,16,0 
65,45,o3,9 
65,5o,5i,9 
65,56,39,9 

66,02,28,0 
66,08.16.1 
66,i4,o4,3 
66,19,52,5 
66,25,40,7 

66,31,29,0 
66,37,17,3 
66,43,o5,6 
66,48,53,9 
66,54,42,3 

67,00,30,7 
67,06,19,2 
67,12,07,7 
67,17,56,1 
67,23,44,5 

67,29,32,9 
67,35,21,4 
67,41,09,9 
67,46,58,4 
67,52,47,0 

67,58,35,6 
68,04,24,1 
68,10,12,7 
68,16,01,3 
68,21,49,9 

68,27,38,5 
68,33,27,1 
68,3g,i5,7 
68,45,04,2 
68,50,52 

68,56,4: 

69-02,29,9 

69,08,18,4 

69,14,07,0 

69,19,55,5 

69,25,44,0 
69,31,32,5 
69,37,21,0 
69,43,09,5 
69,48,58,0 

69,54,46,5 
70,00,34,9 
70,06,23,3 
70,12,11,7 
70,18,00,0 

70,23,48,3 
70,29,36,6 
70,35,24,9 
70,41, i3,i 
70,47,01,3 


1.835  70,52,49,5 

1.836  70,58,37,6 

1.837  71,04,25,7 

1.838  7i,io,i3,l 

1.839  71,16,01,1 
i,84o  71,21,49,8 


347,9 
347,9 
348,0 
348,0 

348,1 

348,1 
348,2 
348,2 
348,2 

343,3 

348,3 
348,3 
348,3 
348,4 

348,4 

348,5 
348,5 
348,4 
348,4 

348,4 

348,5 
348,5 
348,5 
348,6 

348,6 

348,5 
348,6 
348.6 
348,6 

348,6 

348,6 
348,6 
348,5 
348,6 

348,6 

348,5 
348,5 
348,6 
348,5 

348,5 

348,5 
348,5 
348,5 
348,5 

348,5 

348.4 
348,4 
348,4 
348,3 

348,3 

348,3 
348,3 
348,2 
348,2 

348,2 

348,1 
348,1 
348,1 
348,0 
348,0 
348,0 


Loj.  of 
t'  days 


True 
Anom.    U. 


I,84o 
1, 84 1 
1,842 
1,843 
1,844 


1,846 
1,847 
1,848 
1,849 

i,85o 
1. 85 1 
1,852 
1,853 
1,854 

1,855 
1,856 
1,857 
1,858 
1,859 

1,860 
1,861 
1,862 
1,863 
1,864 

1,865 
1,866 
1,867 
1,868 
1,869 

1,870 
1,871 
1,872 
1,873 
1,87 

1,875 
1,876 

1,877 
1,878 

1,879 

1,880 
1,881 
1,882 
1,883 
1,884 

1,885 
1,886 
1,887 
1.888 


1,890 
1,891 
1,892 
1,893 


1,895 
1,896 
1,897 
i,8g8 
1,899 
1,900 


71,21,49,8 
71,27,37,8 
71,33,25,7 
7i,3g,i3,6 
71,45,01,4 

71,50,49,1 
71,56,36,8 
72,02,24,5 
72,08,12,1 
72,13,59,7 

72,19,47,2 
72,25,34,7 
72,31,22,1 
72,37,09,4 
72,42,56,7 

72,48><i3,9 
72,54,31,0 
73,00,18,0 
73,06,05,0 
73,1 1,52,0 

73,17,38,9 
73,23,25,7 
73,29,12,5 
73,34,59,2 
73,40,45,8 

73,46,32,3 

73,52,18 

73,58,o5,i 

74,o3,5i,4 

74,09,37,6 

74,1 5,23,7 

74,21,09,7 

74,26,55,6 

74,32,4i 

74,38,27,3 

74,44, 1 3,0 
74,49,58,6 
74,55,44,1 
75,01,29,6 
75,07,15,0 

75,i3,oo,3 
75,18,45,5 
75,24,30,6 
75,3o,i5,5 
75,36,00,4 

75,41,45,2 
75,47,29,9 
75,53,14,4 
75,58,58,9 
76,04,43,3 

76,10,27,5 
76,16,1 1,6 
76,21,55,6 
76,27,39,5 
76,33,23,3 

76,39,07,0 

76,44,50,6 

76,50,34,1 

76,56,17,5 

77,02,00 

77,07,43,8 


348,0 
347,9 
347,9 
347,8 

347,7 

347,7 
347,7 
347,6 
347,6 

347,5 

347,5 
347,4 
347,3 
347.3 

347,2 

347,1 
347,0 
347,0 
347,0 

346,9 
346,8 
346,8 
346,7 
346,6 

346,5 

346,4 
346,4 
346,3 
346,2 

346,1 
346,0 
345,9 
345,9 
345,8 

345,7 
345,6 
345,5 
345,5 
345,4 
345,3 

345,2 
345,1 
344,9 
344,9 
344,8 

344,7 
344,5 
344,5 
344,4 

344,2 

344,1 
344,0 
343,9 
343,8 

343,7 
343,6 
343,5 
343,4 
343,2 
343,1 
343.0 


Log.  of 
t'  diiys. 


I, goo 

IfJOl 

1,902 
1,903 
1,904 

i,go5 
1,906 
1,907 
i,go8 
1,909 

1,910 

i,9H 
1,912 
1,913 
1,914 

1,915 
1,916 
i,9'7 
1,918 

i,9'9 

1,920 
1,921 
1,922 
1,923 
1,924 

1,925 
1,926 
1,927 
1,928 
1,92g 

1,930 
1,931 
1,932 
1,933 


True 
Anom.  U. 


1,935 
1,936 
1,937 

1,938 
1,939 

1,940 
1,941 
1,942 
1,943 
1,944 

1,945 
1,946 
1,947 
1,948 
1,949 

1,950 
1,951 
1,952 
1.953 
1,954 

1,955 
1,956 
1,957 
1.958 
1,959 
1,960 


77,07,43,8 
77,13,26,8 
77,19,09,7 
77,24,52,5 
77,3o,35,2 

77,36,17,8 
77,42,00,2 
77,47,42,5 
77,53,24,6 
77,59,06,6 

78,04,48,5 
78,10,30,2 
78,16.11,7 
78,21,53,1 
78,27,34,4 

78,33,15,5 
78,38,56,5 
78,44,37,4 
78,50,18,2 
78,55,58,9 

79,01,39,4 
79,07,19,8 
79,1 3,00,0 
79,18,40,0 
79,24,19,9 

79,29,59,6 
79,35,3g,2 
7g,4i,i8,7 
7g,46,58,o 
7g,52,37,2 

7g, 58, 16,2 
8o,o3,55,i 
8o,og,33,8 
8o,i5,i2,3 
8o,20,5o,7 

8o,26,28,g 
8o,32,o6,g 
80,37,44^8 
80,43,22,5 
80,49,00,1 

80,54,37,6 
81,00,14,9 
8 1, o5, 52,0 
81,11,28,9 
81,17.05,7 

81,22,42,3 
81,28,18,8 
81,33,55,1 
81,39,31,2 
81,45,07,1 

8i,5o,42,8 
8i,56,i8,4 
82,01,53,8 
82,07,29,0 

82,l3,04;I 

82,i8,3g,o 
82,24,13,7 
82,29,48,2 
82,35,22,5 
82,40,56,6 
82,46,30,5 


Diff. 


Log.  of 
L'  days. 


343,0 
342,9 
342,8 
342,7 

342,6 

342,4 
342,3 
342,1 
342,0 

341,9 

341,7 
341,5 
341,4 
341,3 

341,1 

341,0 
340,9 
340,8 
340,7 

340,5 

340,4 
340,2 
340,0 
339,9 

339,7 

339,6 
339,5 
339,3 
339,2 

339,0 

338,9 
338,7 
338,5 
338,4 

338,2 

338,0 
337,9 
337,7 
337,6 

337,5 

337,3 
337,1 
336,9 
336,8 

336,6 

336,5 
336,3 
336,1 
335,g 

335,7 

335,6 
335,4 
335,2 
335,1 

334,9 

334,7 
334,5 
334,3 
334,1 
333,g 
333,8 


True 
Anom.    U. 


i,g6o 

1,961 
1,962 
1,963 
1,964 

1,965 
1,966 
1,967 
1, 968 
1,969 

1,970 
1,971 
1,972 
1,973 
1,974 

1,975 
1,976 
1.97' 
1,978 
1 ,979 

1,980 
1,981 
1,982 
1,983 

1,985 
1,986 
1,987 


1,990 

1.99' 

1-99 

1,993 

1,994 

1,995 
1,996 
1,997 

1 ,999 

2,000 
2,001 
2,002 
2,oo3 

2,004 

2,oo5 
2,006 
2,007 
2,008 
2,oog 

2,010 
2,01 1 
2,012 

2,Ol3 
2,Ol4 

2,Ol5 
2)01 

2,017 

2,018 
2,oig 
2,020 


Uiff. 


82,46,3o,5 
82,52,04,3 
82,57,37,9 
83,o3,ii,3 
83,08,44,5 

83,i4,i7,5 

83,i9,5o,3 

83,25.23,^ 

83,3o,55, 

83,36,27,8 

83,41,59.9 
83,47,3i,7 
83,53,o3,4 
83,58,34,9 
84,04,06,2 

84,09,37,3 

84.1 5.08.2 
84,20,38,9 
84, 26,0g  ,4 
84,3i,3g,8 

84,37,09,9 
84,42,39,8 
84,48,09,5 
84,53,39,0 
84,59,08,3 

85,04,37,4 

85. 10.06.3 
85,i5,35,o 
85,2i,o3,5 
85,26,3 

85,31,59,9 
85,37,27,7 
85,42,55,4 
85,48,22,8 
85,53,5o,o 

85,59,17,0 
86,04,43,8 
86,10,10,4 
86,1 5,36,8 
86,21,02,9 

86,26,28,8 
86,3 1, 54,5 
86,37,20,0 
86,42,45,3 
86,48,10,4 

86,53,35,2 
86,58,59,8 
87,04,24,2 
87,09,48,4 
87,15,12,3 

87,20,36,0 
87,25,59,5 
87,31,22,8 
87,36,45,9 
87,42,08,7 

87,47,31 ,3 

87,52,53,7 

87,58,1 5,8 

88,o3,3 

88,08,59.4 

88,i4,2o,g 


333,8 
333,6 
333,4 
333,2 

333,0 

332,8 
332,7 
332,5 
332,3 

332,1 

33 1, 8 
33 1,7 
33i,5 
33 1,3 

33i,i 

33o,9 
33o,7 
33o,5 
33o,4 

33o,i 

329,9 
329,7 
329,5 
329,3 

329,1 

328,9 
328,7 
328,5 
328,3 

328,1 
327,8 
327,7 
327,4 
327,2 

327,0 

326,8 
326,6 
326,4 
326,1 

325,9 

325,7 
325,5 
325,3 
325,1 

324,8 

324,6 
324,4 
324,2 
323,9 

323,7 

323,5 
323,3 
323,1 

322,8 

322,6 

322,4 
322,1 

321, g 

331,7 

32  1,5 

321,2 


Log.  of 
i'  days. 


2,020 
2,021 
2,022 
2,023 
2,024 

2,025 
2,026 
2,027 
2,028 
2,029 

2,o3o 

2,o3l 
2,032 

2,o33 
2,o34 

2,o3 
2,o36 
2,o37 
2,o38 

2,039 

2,o4o 
2,04 1 

2 

2,043 
2,044 

2,045 
2,o46 
2,047 
2,o48 
2,o4g 

2,o5o 

2,05l 
2,o52 

2,o53 
2,o54 

2,o55 
2,o56 
2,067 
2,o58 
2,059 

2,060 
2,061 
2,062 
2  ,o63 
2,064 

2,o65 
2,066 
2,067 
2,068 
2,o6g 

2,070 
2,071 
2,072 
2,073 
2,074 

2,075 
2,076 

2,077 
2,078 
2,070 
2,080 


True 
Anom.  U. 


Diff. 


88,14,20.9 

88,ig,42;i 
88,25,03,1 
88,30,23.9 
88,35,44,4 

88,4i,o4,7 
88.46,24,8 
88,51,44,6 
88,57,04,2 
8g,o2,23,6 

89,07,42,7 
89,13,01,6 
8g, 18, 20,2 
89,23,38,6 
89,28,56,7 

89,34,14,6 
89,39,32,3 
89,44,49,8 
89,50,07,0 
89,55,23,9 

90,00,4^ 
90,05,57,1 
90,11, i3,3 
90,16,29,3 
90,21,45, 

90,27,00,6 
90,32,15,8 
90,37 ,3o,8 
gg,42,45,6 
90,48,00,1 

90,53,14,4 
90,58,28,4 
91,03,42,1 
91,08,55,6 
91,14,08,9 

gi,ig,22,o 
gi, 24,34,8 
91,29,47,3 
gi,34,5g,6 
gi,4o,ii,6 

91,45,23,4 
91,50,34,9 
91,55,46,1 
92,00,57,1 
92,06,07,8 

92,11,18,3 

92,16,2' 

92,21,38,5 

92,26,48,2 

92,31,57,7 

92,37,06,9 
92,42,15,8 
92,47,24,5 
92,52,32,9 
92,57,41,1 

g3,02,49,o 

93,07,56,' 

93,13,04,1 

93,18,11 

g3,23,i8,o 

93,28,24,5 


321,2 
321,0 
320,8 
320,5 

320,3 

320,1 


7,9 

7,7 
7,5 
7 
6,9 

6,7 

6,5 
6,2 
6,0 
5,8 

5,5 

5,2 

5,0 
4,8 
4,5 

4,3 
4,0 
3,7 
3,5 
3,3 

3,1 
2,8 

2,5 
2,3 

2,0 
1,8 

1,5 
1,2 
1,0 
0,7 
0,5 


0,2 
0,0 
'9.7 
309,5 

309,2 

3o8,9 
3o8,7 
3o8,4 
3o8,2 

307,9 

3o7,7 

3o7,4 

3o7 

3o6,8 

3o6,5 

3o6,3 


TABLE    m. 

To  firiil   ttio  truc  aiiuiiialv    f^  coriespuiulinfi  to    the   time    t'  from   the   peiihclioii  in  days,  in  a  parabolic  orbit,   whose    perihelion 
distance  is  tlic  same  as  tlie  mean  distance  oi'  the  sun  Iroiii   tbe  cartb. 


Log.  of 
t'  days 


2,oSo 
2,081 
2,082 
2,o83 
2,084 

a,o85 
a, 086 
2,087 
2,o8S 
2,089 

2,090 
2,091 
2,092 
2,og3 
2.094 

2,og5 
2,096 
2,097 
2,098 
2,099 

2,100 
2,101 
2,102 
2,io3 
2,io4 

2,I05 

2,106 
2,107 

2,108 
2,109 

2,110 

2,11  I 
2,112 
2,1  l3 

2,Il4 

2,ir5 
2,116 
2,117 
2,118 
2,119 

2,130 
3,121 
2,122 
2,123 
2,124 

2,125 
2,126 
2,127 
2,128 
2,129 

3,i3o 

2,l3l 
2.l33 

2;i33 

2,i34 

2,i35 
2,i36 
2,l37 
2,i38 
2,139 

2,l4o 


Truo 
Anoin.    U. 


93,28,24,5 
93,33,30,8 
93,38,36,9 
93,43,42,7 
93,48,48,3 

93,53,53,6 
93,58,58,6 
94,o4,o3,4 
94,09,07,9 
94,14,12,1 

94,19,16,1 
94,24,19,8 
94,29,23,2 
94,34,26,4 
94,39,29,3 

94,44,32,0 
94,49,34,4 
94,54,36,5 
94,59,38,3 
95,04,39,8 

95,09,41,1 
95,14,42,1 
95,19,42,9 
93,24,43,4 
95,29,43,6 

95,34,43,5 
95,39,43,2 
95,44,42,6 
95,49,41,7 
95,54,40,6 

95,39,39,2 
96,04,37,5 
96,09,35,6 
96,14,33,4 
96,19,30,9 

96,24,28,1 
96,29,25,1 
96,34,21,8 
96,39,18,2 
96,44,14,3 

96,49,10,2 

96,54,05,8 
96,59,01,1 
97,o3,56,i 
97,08,50,9 

97,i3,45,4 
97,18,39,6 
97,23,33,5 
97,28,27,2 
97,33,20,6 

97,38, i3,7 
97,43,06,5 
97,47,59,1 
97 ,52,5 1,3 
97,57,43,3 

98,02,35,0 
98,07,26,5 
98,12,17,6 
98,17,08,5 
98,21,59,1 
98,26,49,4 


3o6,3 
3o6,t 
3o5,8 
3o5,6 

3o5,3 

3o5,o 
3o4,S 
3o4,5 
3o4,2 

3o4,o 

3o3,7 
3o3,4 
3o3,2 
3o2,9 

3o2,7 

3o2,4 

3o2,I 

3oi,8 
3oi,5 

3oi,3 

3oi,o 
3oo,8 
3oo,5 
3oo,2 

299,9 

299,7 
299.4 
299,1 
298,9 

298,6 

398,3 
298,1 
297,8 
297,5 

297,2 

297,0 
296,7 
296,4 
256,1 

295,9 
295.6 
295,3 

295,0 

294,8 

294,5 

294,2 
293,9 
293,7 
293,4 

293,1 

292,8 
292,6 
292,2 
292,0 

291,7 
291,5 
291,1 
290,9 
290,6 
290,3 
290,1 


Loi'.  or 

('  days, 


2,l4o 
2,l4l 
2,142 
2,143 

2,i44 

2,145 
2,i46 
2,l47 

2,14s 
2,149 

2,i5o 

2,l5l 
2,l52 

2,i53 

2,1  54 

2,i55 
2,1 56 
2,i57 

2. 1 58 

2. 1 59 

2,160 
2,161 
2,163 
2,i63 
2,164 

2,i65 
2,166 
2,167 
2,168 
2,169 

2,170 
2,171 
2,172 
2,173 
2,174 

2,175 
2,176 
2,177 
2,178 

2,179 

2,180 
2,181 
2,183 
2,i83 
2,1 

2,i85 
2,186 
2,187 
2,188 
2,189 

2,igo 
2,191 
2,192 

2,193 
2,194 

2,195 
a,ig6 

2,197 
2,198 

2,199 
2,200 


'I'iUO 

Anom.  U. 


98,26,49,4 
98,31,39,5 
98,36,29,3 
98,41, 1«,8 
98,46,08,0 

98,50,56,9 
98,55,45,5 
99,00,33,9 
99,o5,22,o 
9g,I0,09,8 

99,14,57,3 
99,19,44,6 
99,24,31,5 
gg, 29,18,3 
99,34,04,7 

99,38,5o,8 
99,43,36,6 
gg,48,22,3 
gg,53,07,5 
99,57,52,5 

00,02,37,2 

00,07,2 

oo,i2,o5,9 

00,16,49,8 

00,21,33,4 

00,26,16,7 
00,30,59,7 
00,35,42,5 
oo,4o,23',o 
00,45,07,2 

00,49,49,1 
oo,54,3o,7 
00,59,12,0 
oi,o3,53,i 
01,08,33,9 

oi,i3,i4,4 
01,17,54,6 
01,22,34,6 
01,27,14,2 
oi,3i,53,6 

01,36,32,7 
01,41,11,5 
01,45, 5o,o 
01,50,28,2 
01,55,06,2 

01,59,43,9 
02,04.21,3 
02,08^8,4 
o2,i3,35,2 
02,18,11,7 

02,22,48,0 
02,27,24,0 
02,31,59,6 
02,36,35,0 
02,41,10,1 

02,45,45,0 
o2,5o,ig,6 
02,54,53,8 
03,59,27,8 
o3,o4,oi,5 
o3,o8,34,9 


Diff. 


290,1 
289,8 
289,5 
289,2 

288,9 

288,6 
288,4 
288,1 
287,8 

287,5 

287,3 
286,9 
286,7 
286,5 

286,1 

285,8 
285,6 
285,3 
285,0 

284,7 

284,5 
284,2 
283,9 
283,6 

283,3 

283,0 
282,8 
282,5 
282,2 

281,9 

281,6 
281,3 
281,1 
280,8 

280,5 

280,2 
280,0 
279,6 
279,4 

279'! 
278,8 
278,5 
278,2 
278,0 

277,7 

277,4 
277,  t 
276,8 
276,5 

276,3 

276,0 
275,6 
275,4 
275,1 

274,9 

274,6 
274,2 
274,0 
273,7 
373,4 
273,1 


Log 
f  days. 


2,200 
2,201 
2,202 
2,2o3 
2,204 

2,2o5 
2,206 
2,207 
2,208 
2,209 

2,210 

2,21 

2,212 

2,2l3 

2,2l4 

2,2l5 
2,216 
2,217 
2,2lS 
2,219 

2,220 
2,221 
3,222 
2,223 
2,224 

2,235 
3,226 
2,227 
2,228 
2,229 

2,23o 
3,23l 
2,232 
2,233 
3,234 

2,235 
2,236 

2,237 

3,238 

2,239 

2,240 
2,241 
2,242 
2,243 
2,244 

2,345 
2,246 
2,247 

2,248 

2,249 

2,25o 
2,25l 
2,252 
2,253 
2,254 

2,255 
2,256 
2,257 
2,2  58 

2,259 
2,260 


'I'rue 
Aiioni.    C/, 


o3,o8,34,9 
o3,i  3,08,0 
o3, 1 7,40,9 
o3,22,i3,5 
03,26,45,8 

o3,3i,i7,8 

03,35,49,5 

o3,4o,20,g 

03,44,52, 

03,49,23,0 

o3,53,53,6 
o3, 58, 23,9 
04,02,53,9 
04,07,23,6 
04,11,53,1 

04,16,22,3 
04,20,5 1,3 
04,25,19,8 
04,29,48,1 
04,34,16,1 

o4,38,43,9 
04,43,11,3 
04,47,38,5 
o4,52,o5,4 
o4,56,32, 

o5,oo,58,4 
o5,o5,24,5 
05,09,50,3 
o5,i4;i5,7 
o5, 1 8,40,9 

o5,23,o5,g 
o5,27,3o,5 
o5,3 1,54,9 
05,36,19,0 
o5,4o,43,8 

o5,45,o6,3 
05,49,29,5 
o5,53,52,5 
o5,58,i5,i 
06,02,37,5 

06,06,59,6 
06,11,21,5 
06,1 5,43,0 
06,20,04,3 
06,24,25,3 

06,28,46,0 
06,33,06,4 
06,37,36,5 
06,41,46,3 
o6,46,o5,g 


),5o,25,2 

),54,44,3 

1,59,02,9 

/,o3,2i,4 

[07,07,39,6 


,11,57,4 
,i6,i5,o 
,20,32,4 
,24,49,4 
,29,06,2 
,33,33,7 


273,1 
272,9 
272,6 
272,3 


271,7 
271,4 
271,2 
270,9 
270,6 

270,3 
270,0 
269,7 
269,5 

269,2 

368,9 
268,6 
268,3 
268,0 

267,8 

267,4 
267,2 
266,9 
266,7 

266,3 

266,1 
265,7 
365,5 

365,2 

265,0 

264,6 
264,4 
264,1 
263,8 

263,5 

263,2 
363,0 
262,6 
262,4 

363,1 

261,9 
261,5 
261,3 
261,0 

260,7 

260,4 
260,1 
259,8 
25g,6 

25g,3 

259,0 
258,7 
258,5 

258,3 

257,8 

257,6 
257,4 
357,0 
256,8 
256,5 

256,2 


jOg.  ot' 
'  days. 


3,360 

3,26 

2,262 

2,363 

2,264 

2,365 

2,266 
2,267 

2,268 

2,26g 

2,270 
2,371 

2,272 
2,273 

2,274 

2,375 
2,276 

2,277 

2,278 
2,279 

2,280 
2,281 

2,282 

2,283 
2,284 


True 
Anom,    U- 


107,33,33,7 
107,37,38,9 
107,41,54,8 
107,46,10,5 
107,50,25,9 

107,54,41,0 
107,58,55,8 
io8,o3,io,3 
108,07,24,6 
108,1 1,38,5 

108,1  5,52,2 

io8,2o,o5,6 
108,24,18 
108,28,31,6 
108,32,44.2 

io8,36,56,5 
108,41,08,5 
108,45,20,3 
108,49,31,7 
108,53,42,9 

108,57,53,8 

109,02,0- 

109,06,14,8 

109,10,24,9 

109,14,34,7 


2,283     109,18,44,2 
,286    log, 32, 53, 5 
2,287 
2,288 
2,28g 


2,2go 
2,391 
2,392 
2,293 
2,294 

2,295 

2,2g6 
2,297 
2,398 
2,29g 

2,3oo 
2,3oi 

2,302 

2,3o3 
2,3o4 

2,3o5 
2,3o6 
2,3o7 
2,3o8 
2,3og 

2,3lO 
2,3ll 
2,3l2 

3,3i3 
3,3i4 

2,3 1 5 
2,3i6 
2,317 
2,3i8 
2,3i9 
2,320 


109,27,03,4 
log, 3i, 11, 1 
iog,35,ig,6 

109,39,27,7 
109,43,35,6 
109,47,43,2 
io9,5i,5o,6 
109,55,57,6 

110,00; 

110,04,11,0 
110,08,17,2 
110,12,23,3 
110,16,28,9 

110,20,34,4 
110,24,39,5 
110,28,44,4 
1 10,32,49,0 
110,36,53,3 

1 10,40,57,4 
110,45,01,1 
110,49,04,6 
110,53,07,9 
110,57,10,8 

111,01, i3, 5 
iii,o5,i5,9 
111,09,18,1 
iii,i3,ig,9 
111,17,21 

111,21,22,9 
111,25,33,9 
111,29,24,71 
111,33,25,2 
111,37,25,5 
iii,4i,25,5 


256,2 

255,9 
255,7 
255,4 

255,1 

254,8 
254,5 
354,3 
253,9 

253,7 

253,4 
253,1 

253,9 
252,6 

252,3 

252,0 

25i,8 
25i,4 

25l,2 

25o,g 

25o,6 
25o,4 
25o,i 
24g,8 

249,5 

249,3 
248,g 
248,7 
348,5 

248,1 

247,9 
247,6 

247,4 
247,0 

246,8 

246,6 
246,2 
246,0 
245,7 
245,5 

245,1 
244.9 
244,6 
244,3 

244,1 

243,7 
243,5 
243,3 
242,9 

242,7 

343,4 
343,3 
241,8 
341,6 

241,4 

24 1,0 
240,8 
240,5 
240,3 
24o,o 
339,7 


Loy.  of 
V  (lays. 


2,330 
2,321 
2,323 
2,323 
2,324 

2,325 
2,326 
2,327 
2,328 
2,329 

2,33o 
2,33i 

3,333 

3,333 
2,334 

2,335 
2,336 
2,337 
2,338 
2,339 

2,34o 
2,341 
2,342 
2,343 
2,344 

2.345 
2,346 
2,347 
2,348 
2,349 

2,35o 
2,35i 

2,352 

2,353 
2,354 

2,355 
2,356 
2,357 
2,358 
2,35g 

2,36o 
2,36i 
2,362 
2,363 
2,364 

2,365 
2,366 
2,367 
2,368 
2,369 

2,370 
2,371 
3,373 
2,373 
2,374 

2,375 
2,376 
2,377 
2,378 
2,379 
3,38o 


True 
Anom.  U. 


111,41,25,5 
111,45,35,3 
111,49,34,6 
111,53,23.8 
111,57,22,7 

112,01,21,3 
112,05,19,7 
112,09,17,8 

Ii2,i3,i5,6 
H2,i7,i3,i 

112,21,10,4 
112,25,07,4 
112,29,04,3 
113,33,00,7 
112,36,56,9 

112,40,52,8 
112,44,/'  " 
112,48,43,9 
ii2,52,3g,i 
112,56,34,0 

1x3,00,28,6 
ii3,o4,33,o 
1 1 3,08, 17,0 
ii3,i2,io,8 
1 13, 16,04,4 

113,19,57,7 
ii3,23,5o,7 
113,27,43,4 
Ii3,3i,35,g 
113,35,28,1 

ii3,3g,2o,i 
ii3,43,ii,8 
ii3,47,o3,3 
ii3,5o,54,5 
1 1 3,54,45,4 

ii3,58,36,i 
114,02,36,5 
114,06,16,6 
114,10,06,5 
ii4,i3,56,i 

114,17,45,5 
114,31,34,6 
114,25,33,4 
114,29,11,9 
ii4,33,oo,2 

114,36,48,3 
ii4,4o,36,i 
114,44,23,6 
ii4,48,io,g 
114,51,57,9 

114,55,44,6 
ii4,59,3i,i 
ii5,o3,i7,3 
ii5,07,o3,3 
115,10,49,0 

ii5, 14,34,4 
115,18,19,6 
ii5,33,o4,6 
11 5,25,49,3 
115,29,33,7 
1 1 5,33,17,9 


Diff. 


239,7 
239,4 
239,2 
238,9 

238,6 

238,4 
238,1 
237,8 
287,5 

237,3 

237,0 
236,8 
236,5 

236,2 

235,9 

235,7 
235,4 

235,3 

234,9 

234,6 

234,4 
234,0 
333,8 
233,6 

233,3 

233,0 

232,7 
232,5 
232,2 

232,0 

23 1,7 

23i,5 

23l,2 

23o,9 

23o,7 

23o,4 
23o,i 

229,9 

229,6 

229,4 

229,1 
228,8 
228,5 
228,3 

238,1 

227,8 
227,5 
227,3 

227,0 

226,7 

226,5 
226,2 
226,0 

225,7 
225,4 
225,2 

225,0 
334,7 

234,4 

324,2 

333,9 


TABLE    III. 

To   find  the  true  anomaly    U,  corresponding   to  the   time  ('  from  the   perihelion  in  days,   in  a  parabolic   orbit,  whose  perihelion 
distance  is  the  same  as  the  mean  distance  of  the  sun  from  the  earth. 


Log.  ol 
('  days 


2,38o 
2.38i 

2,382 

2,383 
2,384 

2,385 
2,386 
2,387 
2,388 
2,389 

2,390 

2,3yl 
2,392 
2,393 
2,394 

2,395 
2,396 
2,397 
2,398 
2,399 

2,400 

2,4oi 

2,4o2 

2,4o3 
2,4o4 

2,4o5 
2,4o6 
2,407 
2,4o8 
2,409 

2,4lO 
2,4ll 
2,4l2 
2,4l3 

2,4i4 

2,4i5 
2,4r6 
2,417 
2,4i8 
2,419 

2,420 
2,421 
2,422 
2,423 
2,424 

2,425 
2,426 
2,427 
2,428 

2,429 
2,43o 

2, 43 1 

2,43? 

2,433 
2,434 

2,435 

2,436 
2,437 
2,438 
2,43g 
2,44o 


True 
Anoin.  U. 


115,33,17,9 
1 1  5,37,01,8 
II  5,40,45,5 
115,44,28,9 

ii5,48,i2,o 

ii5,5i,54jg 

115,55,37,6 

115,59,20,0 

ii6,o3,o2, 

116,06,43,9 

116,10,25,5 
116,14,06,9 
116,17,48,0 
116,21,28,8 
116,25,09,4 

116,28,49,7 
116,32,29,8 
116,36,09,6 
116,39,49,2 
116,43,28,5 

116,47,07,7 
ii6,5o,46,5 
116,54,25,2 
ii6,58,o3,5 
117,01,41,6 

117,05,19,5 
117,08,57,2 
117,12,34,5 
117,16,11,6 
117,19,48,5 

117,23,25,2 
117,27,01,5 
117,30,37,7 
117,34,13,6 
117,37,49,1 

117,41,24,4 
117,44,59,5 
1 17,48,34,3 
117,52,08,9 
117,55,43,3 

117,59,17,3 

ii8,o2,5i 

118,06,24,8 

118,09,58,1 

Ii8,i3,3i,2 

118,17,04,0 
118,20,36,7 
118,24,09,1 
118,27,41,2 
ii8,3i,i3, 

118,34,44,8 
ii8',38,i6,2 
118,41,47,4 
118,45,18,3 
118,48,49,0 

118,52,19,5 
118,55,49,7 
118,59,19,7 
119,02,49,4 
119,06,18,9 
119,09,48,1 


223,9 
223,7 
223,4 
223,1 

222,9 

222,7 
222,4 
222,1 
221,8 

221,6 

221,4 
221,1 
220,8 
220,6 

220,3 

220,1 
219,8 
219,6 
219,3 

219,2 

218,8 
218,7 
218,3 
218,1 

217.9 

217,7 
217,3 
217,1 
216.9 

216,7 

216,3 
216,2 

21 5,9 
2i5,5 

2 1 5.3 

2l5,I 

2i4,8 
2i4,6 

2 1 4.4 

2l4,0 

213.9 
2i3^6 
2i3,3 

2l3,l 

212,8 

212,7 
212,4 
212,1 
211,9 

211,7 

211,4 
211,2 
210,9 
210,7 

210,5 

210,2 
210,0 

2og,7 
209,5 
209,2 
209.0 


Log.  or 

£    days. 


2,44o 
2,44 1 
2,442 
2,443 

2,444 

2,445 
2,446 
2,447 
2,448 
2,449 

2,45o 
2,45i 
2,452 
2,453 
2,454 

2,455 
2,456 
2,457 
2,458 
2,459 

2,46u 
2,461 
2,462 
2,463 
2,464 

2.465 
2,466 
2,467 
2,468 
2,469 

2,470 

2,471 
2,472 
2,473 
2,474 

2,475 
2,476 
2,477 
2,478 
2,479 

2,480 
2,481 
2,482 
2.483 


2,485 
2,486 
2,487 
2,4 

2,4 

2,490 
2,491 
2,49a 
2,493 
2,494 

2,495 
2,496 
2,497 
2,498 
2,499 
2,5oc 


True 
Anoiii.    U. 


19,09,48,1 
19,13,17,1 
19,16,45,9 
19,20,14,4 
19,23,42,7 

19,27,10,7 
19,30,38,5 
19,34,06,1 
19,37,33,4 

ig,4i,oo,5 

19,44,27,3 
19,47,53,9 
19,51,20,3 
19,54,46,4 
ig,58,i2,3 

20,01,38,0 
2o,o5,o3,4 
20,08,28,6 
20,11,53,5 

20,l5,l8,2 


,18,42,7 
,22,07,0 
>,25,3i,o 
1,28,54,8 
,32,18,3 


20,35,41,6 
20,39,04,7 
20,42,27,5 
20,45,50,1 
20,49,12,5 

20,52,34,7 
20,55,56,6 
20,59,18,3 
2i,02,3g,7 
21,06,00,9 

2 1 ,09,2 1 ,9 
21,12,42,7 

21,l6,o3,2 

21.19.23. 5 
21,22,43,6 

21,26,03,4 
21,29,23,0 
21,32,42,4 
2  1,36,01,5 
21,39,20,4 

2i,42,3g,i 
21,45,57,6 
21,49,15,. 
21,52,33,8 

2 1. 55.5 1. 6 

21,59.09,1 
22,02,26,4 
22,05,43,5 
22,09,00,4 
22,12,17,0 

22,i5,33,4 
22,18,49,6 

22,22,o5,5 
22,25,21,3 

22,28,36,8 

22, 3l, 52,0 


Dlff. 


209,0 

208,8 
208,5 
208,3 

208,0 


207,6 
207,3 
207,1 

206,8 

206,6 
206,4 
206,1 
205.9 

2o5,7 

2o5,4 

205,2 
204r9 

204,7 
2o4,5 
204,3 

2o4,0 

2o3,8 
2o3,5 

2o3,3 

2o3,I 

202,8 
202,6 
202,4 

202,2 

201,9 
201,7 

201,4 
201,2 

201,0 

200,8 
200,5 
200,3 
200,1 

99,8 

99,6 
99,4 
99,1 

98.9 

98,7 

98,5 
98,2 

g8,o 
97,8 

g7,5 
97,3 

97,. 

96,9 

96,6 
96,4 

96,2 

95,9 
95,8 
95,5 

95,2 

95.1 


Log.  ol 


2,5oo 
2,5oi 

2,502 

2,5o3 
2,5o4 

2,5o5 
2,5o6 
2,507 
2,5o8 

2,509 

2,5lO 
2,5ll 
2,5l2 

2,5i3 
2,5i4 

2,5i5 
2,5i6 
2,5i7 
2,5i8 
2,519 

2,520 

2,521 
2,522 
2,523 

2,524 

2,525 

2,526 

2,527 

2,528 
2,52g 

2,53o 
2,53i 

2,532 

2,533 

2,534 

2,535 
2,536 

2,537 

2,538 

2,539 

2,540 

2, 54 1 

2,542 

2,543 
2,544 

2,545 
2,546 
2,547 
2,548 
2,549 

2,55o 
2,55i 

2,552 

2,553 

2,554 

2,555 
2,556 
2,557 
2,558 
2,559 
2,56o 


True 
Anoni .  U. 


d    m    s 
22,3l,52,0 
22,35,07,1 
22,38,22,0 
2  2, 4 1,36,6 

22,44, 5i,o 

22,48,05,2 
22,5l,ig,2 
22,54,33,0 
22,57,46,6 

23,oo,5g,9 

23,o4,i3,o 
23,07,25,8 
23,10,38,4 
23,i3,5o,7 
23,17,02,9 

23,20,14,8 
23,23,26,5 
23,26,38,0 

23,2g,4g,2 

23,33,00,3 

23,36,11,1 
23, 3g, 2 1,7 
23,42,32,1 
23,45,42,3 
23,48,52,3 

23,52,02,0 
23,55,11.5 
23,58,20,8 
24,01,29,9 
24,04,38,8 

24,07,47,5 
24,10,55,9 
24,14,04,2 
24,17,12,2 
24,20,20,0 

24,23,27,6 
24,26,35,0 
24,29,42,2 
24,32,4g,i 
24,35,55,9 

24,39,02,4 
24,42,08,7 
24,45,14,8 
24,48,20,7 
24,51,26,4 

24,54,31,8 
24,57,37,1 
25,00,42,1 
25,o3,47,o 
25,o6,5i,6 

25,09,56,0 

25,l3,00,2 

25,16,04,2 
25,19,08,0 

25,22,11,5 

25,25, i4-Q 
25,28,18,0 
25, 3 1,2 1,0 
25,34,23,7 
25,37,26,2 
25,40,28,5 


Diff. 


95,1 
94:9 

94,6 
94,4 

94,2 

g4,o 
g3,8 
93,6 
g3,3 

g3,i 

92,8 
92,6 
92,3 
92,2 

9'>9 

gi,7 
91,5 
91,2 
91,1 

go,8 

90,6 
90,4 
90,2 
90,0 

89,7 
8g,5 
8g,3 

69,1 

88,9 

88,7 

88,4 
88,3 
88,0 
87,8 

87,6 

87,4 
87,2 
86,9 
86,8 

86,5 

86,3 
86,1 
85,9 
85,7 

85,4 

85,3 
85. o 
84.9 
84,6 

84,4 

84,2 
84,0 
83,8 
83,5 

83,4 

83,1 
83,o 
82,7 
82,5 
82,3 
82,1 


Log.  of 
(  (luys 


2,56o 
2,56l 
2,562 
2,563 
2,564 

2,565 
2,566 
3,567 
2,568 
2,56g 

2,570 
2,571 
2,572 
2,573 
2,574 

2,575 
2,576 

2,577 
2,578 
2,579 

2,58o 
2,58i 

2,582 

2,583 
2,584 

2,585 
2,586 
2,587 
2,588 
2,589 

2,590 
2,591 
2,5g2 
2,593 
2,594 

2,595 
2 ,596 
2,597 
2,5g8 
2,5g9 

2,600 
2,601 
2,602 
2,6o3 
2,604 

2,6o5 
2,606 
2,607 
2,608 
2,6og 

2,610 
2,611 
2,612 
2,6i3 
2,614 

2,6i5 
2,616 
2,617 
2,618 
2,6ig 
2,620 


Ti  uc 
Au 0111.    U. 


25,40,28,5 
25,43,30,6 

25,46,32,5 
25,49,34,2 
25,52,35,7 

25,55,37,0 
25,58,38,1 
26,01,38,9 
26,04,39,6 
26,07^^0,1 

26,10,40,3 
26,13,40,4 
26,16,40,2 
26,19,39,8 
26,22,39,3 

26,25,38,5 
26,28,37,5 
26, 3 1,36,3 
26,34,35,0 
26,37,33,4 

26,4o,3i,6 
26,43,29,6 
26,46,27,4 
26,49,25,0 
26,52,22,4 

26,55,19,6 
26,58,16,6 
27,01, i3,4 
27,04,10,0 
27,07,06,4 

27,10,02,6 
27,12,58,6 
27,15,54,4 
27,18,50,0 
27,21,45,4 

27,24,40,5 
27,27,35,5 
27,3o,3o,3 
27,33,24,9 
27,36,19,3 

27,3g,i3,5 
27,42,07,5 
27,45,01,3 
27,47,54,9 
27,50,48,3 

27,53,41,6 
27,56,34,6 
27,59,27,4 
28,02,20,1 
28,05,12,5 

28,08.04.7 
28,10,56,8 
28,13,48,7 
28,16,40,3 
28,19,31,8 

28,22,23,1 
28,25,14,2 
28,28,05,1 
28,30,55,8 
28,33,46,3 
28,36.36,7 


82,1 
81,9 
81,7 
81,5 

81,3 

81,1 
80,8 
80,7 
80,5 

80,2 

80,1 
79,8 
79,6 
79,5 

79,2 

79,0 
-8.8 
78,7 
78,4 
78,2 

78.0 
77,8 
77,6 
77,4 

77.2 

77,0 
76.8 
76.6 
76^ 
76,2 

76,0 
75,8 
75,6 
75,4 
75,1 

75,0 
74,8 
74,6 
74,4 

74,2 

74,0 
73,8 
73.6 
73,4 
73,3 

73,0 
72,8 
72,7 
72,4 

72,2 

72,1 
71,9 
71.6 
71,5 
71,3 

71,1 
70,9 
70,7 
70,5 
70,4 
70,2 


Log.  oi 
I'  days. 


2,620 
2,621 
2,622 
2,623 
2,624 

2,625 
2,626 
2.627 
2,628 
2,629 

2,63o 
2,63 1 

2.632 

2,633 
2,634 

2.635 
21636 
2,637 
2,638 
2,63g 

2,640 
2,64i 
2 ,642 
2.643 
2,644 

2,645 
2,646 
2,647 
2,648 
2,64g 

2,65o 
2,65 1 

2,652 

2,653 
2,654 

2,655 
2,656 
2,657 
2,658 
2,659 

2,660 
2,661 
2,662 
2,663 
2,664 

2,665 
2,666 
2.667 
2;668 
2,669 

2,670 
2,671 
2,672 
2,673 
2,674 

2,675 
2,676 
2,677 
2,678 
2,679 
2,680 


True 
Anoni.  U. 


28,36,36 

28,3g,26,g 

28.42,16.8 

28,45.06,5 

28,47,56,0 

28,50,45.4 

28,53,34.5 

28,56,23,5 

28,59,12 

29,02,00,9 

29,04,49,3 
29,07,37.5 
29,10,25,5 
29,13, i3,3 
29,16,01,0 

29,18,48,4 

29,21,35,7 

29,24,22,8 

29,27,0g 

29,29,56,4 

29,32,43,0 
2g,35,2g.3 
29,38,15,5 
29,41,01,4 
29,43,47,2 

29,46,32,8 
29,49,18,3 
29,52,03.5 
29,54,48,6 
29,57,33,4 

3o,oo,]8,i 
3o,o3,02.6 
30,05,46^8 
3o,o8,3o,9 
3o,i  1,14,8 

3o,i3,58,6 
3o, 16,42, 1 
3o,ig,25,5 
3o,22,or 
30,24,5 

30,27,34,5 
3o, 30,17, 3 
30,32,59,6 
3o,35,4i,9 
3o,38,24,o 

3o,4i,o6,o 
3o,43,47,7 
30,46,29,3 
30,49,10,7 
3o,5i,52,o 

3o, 54,33,0 
3o,57,i3,S 
30,59,54,5 
3i,o2,35,o 
3i,o5,i5,3 

31,07,55,5 
3i, 10,35, 5 
3i,i3,i5,3 
3i,i5,54,9 
3i,i8,34,3 
3i,2i,i3.6 


Dim 


70,2 

6g,9 
6g,7 
6g,5 

6g,4 

69,1 
69,0 
68,8 
68,6 

68,4 

68,2 
68,0 
67,8 
67,7 
67,4 
67,3 
67,1 
66.9 
66,7 

66,6 

66,3 
66,2 
65.9 
65,8 

65,6 

65,5 
65,2 
65,1 
64,8 

64,7 

64,5 
64,2 
64,1 
63,9 

63,8 

63,5 
63,4 
63,2 
63 ,0 

62,8 

62,7 
62,4 
62,3 
62,1 

62,0 

61,7 
61,6 
61,4 
61,3 

61,0 

60,8 
60,7 
60,5 
60,3 

60,2 

60,0 
59,8 
59,6 
59,4 
59,3 
59,0 


TABLE  111. 

To   find   llie  true  anomaly    U,  corresponding  to  the   time  t'  from  llie   perilielion  in  days,  in  a  parabolic  orbit, 
distance  is  llie  same  as  ihe  mean  distance  of  the  sun  Irom  the  earth. 


whose  perilielion 


I    (lay- 


2,6So 
2,681 

2,683 
2,684 

2,685 
2,686 
2,687 
2,688 
2,689 

2,6go 
2,691 
2,693 
2,693 
2,(59-1 

2,695 
2,696 
2 ,697 
2,(k)6 
21699 

2,700 
2,701 
2,703 
2,703 
2,704 

2,705 
2,706 

2,707 
2,708 
2,709 

2,710 
2,71 1 
2,712 
2,7 1 3 
2,714 

2,71 5 
2,716 
2,71 
2,718 

2,719 

2,720 
2,721 
2,722 
2,723 
2,724 

2,725 
2,736 
2,727 
2,728 
2,739 

2,73o 
2,73i 
2,733 
2,733 
2,73i 

2,735 
2,736 
2,737 
2,738 
2,739 
2,740 


'i'rue 
Aiioiii.  U. 


1 3 1.2 1. 1 3.6 
i3i,23,52,6 
i3i,26,3i,5 
131,29,10,2 
1 3 1, 3 1, 48,8 

1 3 1, 34,27, 1 

1 3 1.37.05. 3 

1 3 1.39.43.4 
1 3 1,42, 2 1, 3 
i3i,44,58,8 

1 3 1, 47,36,3 
i3i,5o,i3,6 
i3i,52,5o,8 

1 3 1.55.27.7 

1 3 1. 58 .04.5 

i32,oo,4r,i 

1 32.03.17.6 
i32,o5,53,8 
132,08,29,9 
i32,ii,o5,8 

i32,i3,4i,6 
132,16,17,3 
i32, 18,52,6 

l32,2t,27, 
132,24,02,9 

133,26,37,8 

i32,2g,i2,5 
i32,3i,47,i 
i32,34,3i,5 
132,36,55,7 

132,39,29,7 
i32,42,o3,6 
132,44,37,3 
i32,47,io,8 
132,49,44,2 

133,52,17,4 
i32,54,5o,5 
i32,57,23,3 
i32, 59,56,0 
133,02,28,5 

i33,o5,oo,g 
133,07,33,1 
i33,io,o5,i 
i33,i2,36,9 
i33,i5,o8,6 

133,17,40,1 
i33,2o,i  [,4 
133,22,43,6 
i33,25,i3,6 
133,27,44,4 

i33,3o,i5,i 
133,32,45,6 
1 33,35, 16,0 
133,37,46,2 
i33,4o,i6,2 

i33,42,46,i 
i33.45,i5.8 
1 33,47,45,3 
i33,5o,i4,7 
133,53,43,9 
i33,55,i2,9 


59,0 
58,9 
58,7 
58,6 

58,3 

58,3 
58,1 
57,8 
57,6 

57,5 

57,3 
57,2 
56,9 
56,8 

56,6 

56,5 
56,2 
56,1 
55,9 

55,8 

55,6 
55,4 
55,2 
55,1 

54,9 

54,7 
54,6 
54,4 
54,3 

54,0 

53,9 
53,7 
53,5 
53,4 

53,2 

53,1 
52,8 
52,7 
52,5 

52,4 

53,2 
52,0 

5i,8 

5. ,7 

5i,5 

5i,3 
5i  ,2 
5i,o 
5o,8 

5o,7 

5o,5 
5o,4 
5o,2 
5o,o 

49,9 

49,7 
49,5 
49,4 
49.2 
49,0 
48. q 


L  d&yi. 


2,740 
2,741 
2,743 
2,743 

2,744 

2,745 
2,746 
2,747 
2,748 
2,749 

2,75o 

2,75l 

2,753 

2,753 
2,754 

2,755 

2,756 
2,757 
2,758 

2,759 

2,760 
2,761 
3,763 
3,763 
2,764 

2,765 
2,766 
3,767 
3,768 
3,769 

2,770 

2,771 
2,772 
2,773 
2,774 

2,775 
3,776 
2,777 
2,778 
2,779 

3,780 
2,-81 
2,783 
2,783 
2,784 

2,785 
2,786 
2,78- 
2,788 
2,789 

2,790 

2,791 
2,793 

3,793 

2,794 

2,795 
3,796 

2,797 
3,798 

2,799 
2,800 


T,u.j 
Ailun).     £/. 


l33,55,I3,9 

i33,57,4i,8 
1 34 ,00, 1 0,6 
134,03,39,3 
1 34,05,07,6 

134,07,35,8 
1 34,10,03,9 
i34,i2,3i,8 
1 34, 14,59,6 
134,17.27,2 

134,19,54,7 

l34,22,22,0 
134,34,49,1 
134,27,16,0 
134,39,42,8 

i34,32,og,4 
134,34,35,9 
134,37,02,3 
134,39,38,4 
1 34,4 1, 54,4 

1 34,44,30,3 
134,46,45,9 
i34,4g,ii,4 

1 34.5 1.36.8 
134,54,02,0 

1 34.56.27.0 
i34,58,5i.9 
i35,oi,i6,6 
i35,o3,4i,3 
i35,o6,o5,6 

135,08,39,8 
i35,io,53,9 
i35, 13,17,9 
i35,i5,4i,7 
i35,i8,o5,3 

135,30,28,8 

135. 33.53.1 

i35,35,i5,3 
i35,27,38,2 
i35,3o,oi, 

i35,32,23,8 
1 35,34,46,3 
135,37,08,7 

1 35.39.30.9 
i35,4i,53,o 

i35,44,i4,9 
135,46,36,7 
135,48,58,3 
i35, 51,19,8 
1 35,53,4 1,3 

135,56,03,3 
135,58,33,3 
1 36,00,44,3 
i36,o3,o4,9 
i36,o5,25,5 

1 36,07,45,9 
1 36, 10,06, 3 
1 36, 13, 36,3 
1 36, 1 4,46,3 
i36,i7,o6,i 
i36,i9,35,8 

a22 


148,9 
148,» 

i48,6 
i48,4 
1 48,2 

i48,i 
147,9 
i47,a 
147,6 

147,5 

147.3 
147.1 
i46,9 
1 46,8 

1 46,6 

i46,5 
i46,3 
i46,3 
1 46,0 

145,8 

■  45,7 
i45,5 
i45,4 
145,3 

145,0 

144,9 
144,7 
144,6 
i44,4 

i44,3 

i44,i 
144.0 
143,8 
143,6 

i43,5 

143,3 
143,1 
143,0 
142,9 

143,7 

i43,5 
142,4 
143,3 
143,1 

i4i,9 

i4i,8 
i4i,6 
i4i,5 
i4i,4 

i4i,i 

i4r,o 
140.9 
1 4"  ,7 
1 40,6 

i4o,4 

i4o,3 
1 40,1 
i4o,o 
139,8 
139,7 
i3q.5 


3,800 
3,801 

3,8o2 

3,8o3 

2,804 

2,8o5 

2 ,806 

2,807 
2,808 

3,809 
2,810 

2,811 
2.812 

2,8i3 

2,814 

2,8i5 

2,816 
3,817 
2,818 

3,819 

3,820 

2,821 

2.822 

2;823 

2,824 

2,835 
3,826 
2,827 
2,828 
2,829 

2,83o 
2,83 1 

2,833 

3,833 
2,834 

2,835 
2,836 
2.837 
3,838 
3,839 

3,84o 
2, 84 1 

2,843 

2,843 
2,844 

2,845 

2,846 

2,847 

3,6 

2,849 

2,85o 
3,85 1 

2,853 

2,853 
2,854 

2,855 
2,856 
2,85 
3,858 
3,859 
3,860 


'I'rue 
A  null).  {/, 


36,19,35,8 
36,31,45,3 
36,24,04,7 
36,36,23,9 
36,28,42,9 

36,3 1,0 1, 8 
36,33,30,6 
36,35,39,3 
36,37,57,7 
36,4o,i6,o 

36,43,34,3 
36,44,52,2 
36,47,10,1 
36,49,27,8 
36,5 1,45,4 

36,54,02,8 
36,56,30,1 
36,58,37,2 
37,00,54,2 
37,03,1 1,1 

37,05,27,8 
37,07,44,4 
37,10,00,8 
37,12,17,0 
37,14,33,1 

37,16,49,1 
37,19,04,9 
37,31,20,6 
37,23,36,2 
37,25,5i,6 

37,28,06,8 
37,3o,2i,9 
37,32,36,9 
37,34,51,7 
37,37,06,4 

37,39,20,9 
37,41,35,3 
37,43,49,6 
37,46,03,7 
37,48,17,6 

37,50,3 1, 4 
37,52,45,1 
37,54,58,7 
37,57,12,1 
37,59,25,3 

38,01,38,4 
38,o3,5i,4 
38,o6,o4,3 
38,08,16,9 
38,10,39,4 

38,i2,4i,8 
38,14,54,1 
38,17,06,2 
38,19,18,3 
38,3i,3o,o 

38,33,4i,7 
38,35,53,3 
38, 38,04 
38,3o,i6,o 

38,33,37,3 

38,34,38,3 


39,5 
39,4 
39,2 
39,0 

38,9 

38,8 
38,6 
38,5 
38,3 

38,3 
38,0 
37,9 
37,7 
37,6 

37,4 
37,3 

37,1 
37,0 
36,9 

36,7 

36.6 
36,4 
36,3 
36,1 

36,0 

35,8 
35,7 
35,6 
35,4 

35,2 

35,1 
35,0 
34,8 
34,7 
34,5 

34,4 
34,3 
34,1 
33,9 

33,8 

33,7 
33,6 
33,4 
33,2 

33,1 

33,0 
32,8 
33,7 
33,5 

33,4 

33,3 

33,1 

33,0 
3i,8 

3t,7 

3i,6 
3 1. 4 
3i,3 

3l,3 

3 1,0 
3o,q 


Log.  al 
I  .luy-~. 


3,660 
3, 861 
2,863 

3,863 
2,864 

3,865 
2,866 
3,867 
2,868 
2,869 

3,870 
2,871 
2,873 
3,873 
2,874 

2,875 
2,876 
2,877 
2,878 
2,879 

2,880 
3,881 
2,882 
3,883 
2,884 

2,885 
2,886 
3,887 

3,8 


2,890 
3,8gi 
3,892 
2,8g3 


2,895 
2,896 
2,897 
2,898 
2,899 

2, goo 
2,901 
2,902 
2,903 
2,904 

3,9o5 
2 ,906 
3,90 
2,908 
2,909 

2,910 

2.9" 

3,913 
2913 

2,914 
2.915 

2,916 

2.917 

2,918 

2.919 

3,930 


Ti  uo 
Anoni,    U. 


38,34,38,3 
38,36,49,1 
38,38,59,8 
38,4 1, 10,4 
38,43,30,9 

38,45,31,3 
38,47:41,4 
38,4g,5i,4 
38,53,01,3 
38,54,11,1 

38,56,20,8 
38,58,30,3 
3g,oo,3g,6 
39,03,48,9 
39,04,58,0 

39,07,06,9 
3g,og,i5,7 
39,1 1,34,4 
39,13,33,0 
3g,i5,4i,4 

39,17,49,7 
39,19,57,8 
39,23,05,8 
3g,34,i3,7 
3g,36,2i,5 

39,38,39,1 

3g,3o,36,6 

39,33,43,9 

39,34,51 

39,36,58,3 

39,39,05,1 
3g,4i,i  i.g 
3g,43,i8,6 
3g,45,35,3 
39,47,31,6 

39,49,37,9 
39,51,44,0 
39,53,50,0 
3g,55,55,9 
39,58,01,7 

40,00,07,3 

40,03,I3,8 

4o,o4,i8,3 
40,06,33,4 
40,08,28,5 

40,10,33,5 
4o,i  2,38,3 
4o, 14,43,0 
40,16,47,6 
40,18,53,0 

40,20, 56, 4 
4o, 23,00,6 
40,35,04.6 
40,37,08,6 
40,39,13,4 

4o,3i,t6,i 
40,33.19,6 
4o,35,33,i 
40,37,36.4 
40.39,39,6 
40.41.32.6 


3o,9 
3o,7 
3o.6 
3o,5 

3o,3 

3o,2 

3o,o 

29.9 
39,8 

29,7 

29,5 
39,3 

39,3 
29,' 
28,g 

28,8 
38,7 
28,6 
28,4 
28,3 


27.9 
27,8 

27,6 

37.5 
37,3 
37,2 
27,1 
26,9 

36,8 
26,7 
36,6 
36,4 

36,3 

36,1 

36,0 
25,9 
35,8 

25,6 

25,5 
35,4 

35,3 
25,1 

25,0 

34,8 
34,7 
34,6 

24: 

24,4 

24,2 
34,0 
34,0 

33,8 
33,7 

33,5 
33,5 
33,3 

33,3 

33,0 
33.Q 


1..1J;.  t 

I'  (l.iys 


2,920 
2,931 
2,923 
2,933 
2,924 

2,925 
2 ,926 
2,927 
2,938 
2,929 

2,930 
3,931 
2,933 
2,933 
2,934 

2,935 
2,936 
2,937 

2,g38 
2,93g 

3,g4o 
2,941 
3.943 
3,943 
2,944 

2,945 
2.946 
2,947 
3,948 

2,949 

3,950 
3,951 
3,953 
2,953 
2,954 

2,956 
2-957 
3,958 
2,959 

3,960 
2,961 
3,963 
3,963 
3,964 

2,965 
2,966 
2,967 
2,g68 
2,969 

2,970 
2,971 

2,9' 

2,973 

2, .974 

2,975 
2,976 
2,977 
2,978 

2-979 
2.< 


'J'rue 
Anom.  U. 


40,4 1,32, 6 
40,43,35,5 

4o,45,38,3 
40,47,41,0 
40,49,43,5 

40,51,45.9 
4o,53,48,3 
4o,55,5o,3 
40,57,52,4 
40,59,54,3 

4 1.01.56.0 
41,03,57,7 
4 1, 05,59, 3 
41,08,00,6 
4i,io,oi,g 

4i,i2,o3,o 
4i,i4,o4,i 
4i,i6,o5,o 
4i,i8,o5,7 
41,20,06,4 

4i,22,o6,g 
41,24.07,3 
4i  .26,07,6 
4iJ38,o7,8 
4 1,30,07,8 

41,32,07,7 
41,34,07,5 
41,36,07,1 
4i,38,o6,7 

4 1.40.06.1 

4i,43,o5,4 
4 1, 44 .04 ,6 
4i,46,o3,6 
4 1,48,03,5 
4i,5o,oi,3 

41,52,00,0 
4r,53,58,6 
41,55,57,0 
41,57,55,3 
41,59,53,5 

43,01, 5i,6 
43,o3,4g,6 
43,o5,47,4 
43,07,45,1 
43,09,42,7 

43,1  i,4o,3 
43,13,37,5 
43,i5,34,8 
43,17,31,9 
42,19,28,9 

42,21,35,7 
43,33,33,5 
43,35,19,1 
42,27,1 5,f 

42,29,I2,C 

42,3i,o8,3 
42,33,04,4 
42,35,00,4 
43,36,56,4 

43,38,53,3 

43,40,47.' 


22,9 
33,8 

3  2,7 
33,5 

3  2,4 

33,3 
33,1 
33,1 
31,9 

21,7 

21,7 
31,5 
21,4 
21,3 

21,1 

21,1 

20,9 
20,7 
20,7 

20,5 

20,4 
20,3 
20,2 
20,0 

19,9 
19,8 
19,6 
19,6 
19,4 
19,3 

19,2 
19,0 
18,9 
18,8 

.8,7 
18,6 
18,4 
18,3 
18,2 


18,0 
17,8 
17,7 
17,6 

17,5 

17,3 
.7,3 
17,1 
17,0 

16,8 

16,8 
16,6 
16,5 
16,4 
16,3 

16,1 
16,0 
16,0 
1 5,8 
1 5,6 
1 5.6 


TABLE    III. 

To  finil   the  true  anomaly    U,  correspondin»   to    the   time    V  liora    the   peiihelion   in  days,   in  a  p.iiab6lic  orbit,  whose   perihelioB 
distance  is  tlie  same  as  tlie  mean  distance  of  the  sun  from  the  earth. 


2,982 
2,9"- 
2,9 

2,985 
2,986 
2,987 
2,988 
2,989 

2,990 

2-99' 
2,992 
2.993 
2,994 

2,995 
2,996 
2.997 
2,998 

2>999 
3,000 


True 
Ailuin.    U. 


142,40,47,8 
142,42.43,4 
142,44.38,8 
142,46,34,3 
142,48,29,4 

142, 5o, 24, 5 
142,52,19,4 
142,54,14,3 
142,56,09,1 
i42,58,o3,7 

142,59,58,2 
143,01,52,6 
i43,o3,46,9 
i43,o5,4i,i 
143,07,35,2 

143,09,29,1 
143, 1 1,23,0 
143, i3, 16, 7 
i43,i5,io,3 
i43,i7,o3.8 
143,18,57,3 


ii5,6 
1 1 5,4 
1 1 5,4 

Il5,2 

1 1 5, 1 

"i4,9 
1 14,9 
ii4,8 

1 14.6 

114,5 

ii4,4 
1 1 4,3 

Il4,2 

ii4,i 
1 1 3,9 

1 1 3,9 

1 1 3.7 
1 1 3,6 
ii3,5 
ii3,5 


£'  liay 


3,00 

3,0 

3,02 

3,o3 
3,04 

3,o5 
3,06 
3,07 
3,oS 
3,oy 

3,10 
3,11 
3,12 
3,i3 
3,i4 

3. 

3,16 

3,17 

3,18 

3,19 

3,20 
3,21 
3,22 
3,23 
3,24 
3,25 


True 
Anoin.    U. 


143,18,57,3 

143,37,44,7 
i43,56,2o,8 
i44,i4,45,6 
144,32,59,4 

i44,5i,o2,5 
145,08,54,8 
i45,a6,36,5 
145,44,07,7 
146,01,28,(5 

146,18,39,3 
146,35.39,9 
i46,52,3o,5 
147,09,11,3 
147.25,42,5 

147,43,04,1 
i47,58,i6,2 
148,14.19,0 
i48,3o,i2,5 
148,45,56,9 

149,01,32,3 
149,16,58,9 
149,33,16,6 
149.47.25,7 
1 50,02,26,3 
i5o,i7,i8,2 


1127,4 
1 1 16,1 
1 104,8 
1093,8 

[o83,i 

1072,3 
1 06 1 ,7 

105l,2 

1  o4o,9 
io3o,7 

1020,6 
I  o  !  0,6 
1000,8 
991.2 
981,6 

973,1 
962,8 
953,5 
944,4 
935,4 
926,6 
9 '7.7 

909.' 
900,5 
892,0 
883,7 


Luj;.  ol 
/'  days. 


3,25 
3,26 
3,2- 
3,2b 
3,29 

3,3o 
3,3i 
3,33 
3,33 
3,34 

3,35 
3,36 
3,37 
3,38 
3,39 

3,40 
3,41 
3,42 
3,43 
3,44 

3,45 
3,46 
3.4- 
3,48 
3,4o 
3,5o 


'I'rue 
Anom.    V. 


l5o,I7,l8,2 
l5o,32,ol,c, 
1 50,46,37,  j 
1 5 1, 01, 04,5 
i5i,i5,23,5 

151,29,34,7 
i5i,43,38,o 

1 5 1. 57.33.5 

l52,II,21,l 

i52, 25,01,3 

i52,38,34,o 
152,51,59,1 
1 53,05,16.9 
i53,i8,27;5 
i53,3i,3o,8 

153,44.27,1 
153,57,16,3 
154,09,58,5 
i54,22,33,g 

1 54.35.02.6 

154,47.24,4 
154,59,39,6 
1 55, 1 1,48, 
i55,23,5o,5 
155,35,46.2 
1 55,47,35,6 


I)  I  ft'. 


883,7 
875,4 
867,2 
859,0 

85i,2 

843,3 
835,5 
827,6 
820,2 

812,7 

8o5,i 
797.8 
790,6 
783,3 

776,3 

769.2 
762,2 
755,4 
748,7 

74 1, 8 

735,2 
728,8 
722,1 
7 1 5,7 
709,4 
7o3,i 


l.„g.  ..!■ 

1    (J.iy3. 


3,5o 
3,5i 
3,53 
3,53 
3,54 

3,55 
3,56 
3,57 
3,58 
3,59 

3,60 
3,61 
3,63 
3,63 
3,64 

3,65 
3,66 
3.67 
3,68 
3,69 

3',70 

3,71 

3,73 

3,73 

3.7 

3i75 


Anoin.    U. 


55,47,35,f 
55,59,18,7 
56,10,55,5 
56,32,26,3 
56,33,5o,8 

56,45,09,4 
56,56,22,1 
57,o7,28,fc 
57,18,29,7 
57,29,24,8 

57,40,14,3 
57,5o,58,o 
58,01,36,3 
58,i2,o8,t 
58,22,36,0 

58.32,57,7 
58,43,14,1 
58,53,25,3 
59,o3,3i,f 
59,1 3,3 1,6 

59,23,27,1 
59,33,17,5 
59,43,02,^ 
59,53,43,3 
60,02,18,6 
60,11,49,1 


703,1 
696,8 
690,7 
684,6 

678,6 

672,7 
666,7 
660, g 
655,1 

649.5 

643,7 
638,2 
633,6 
637,3 

621,7 

616,4 
611,1 
6o5,8 
600,6 

595,5 

590,4 
585,3 
58o,4 
575,4 
570,5 
565,6 


Lug.  ul 
t    days. 

3,75 
3,76 

3,77 
3,7b 

3,79 

3,80 
3,81 
3,82 
3,83 
3,84 

3,85 
3.86 
3,87 
3,8t 
3,89 

3,90 
3,91 
3.93 
3,93 
3,94 

3,95 
3,96 
3,07 
3,cjb 

3,9t 
4,00 


'J'rue 
Anorn.    t/. 


60,11,49,1 
60,21,14,7 

60. 30. 35.6 

60.39.51 .7 

6o,4g,o3,(. 

6o,58,og,7 
61,07,11,9 
61,16,09.5 
61 ,25,02,5 
6i,33,5i,i 

61,42,35,3 

6i,5i,i5,o 

61,59,50,4 

63,08,31 

62,16,48,3 

62,25,11,0 
62,33,39,4 
63,41,43.6 
63,49,53,b 
62,58,00,1 

63,o6,o2,o 
63,i4,oo,i 
63,21,54,2 
63,39,44,5 
63,37,3o,t 
63 ,45,1 3,4 


5,00    172,32,09,2 


565,6 
56o,9 
556,1 
55i,3 

546,7 

543,2 
537,6 
533,0 
528,6 

524,1 

519,8 
5i5,4 
5ii,i 
5o6,8 

5o2,7 

498,4 
494,3 
490,3 
486,3 


478,1 
474,1 
470,3 
466,3 
462,6 


TABLE    IV. 

This  tahle  is  given  for  the  purpose  of  computing  the  true  anomaly  k,  from  the  time  t  from  the  perihelion  ;  in  a  very  excentrical 
orbit,  whether  it  be  an  ellipsis  or  hyperbola.  The  excentricity  is  represented  by  c,  and  the  periheliim  distance  by  D.  In  using 
this  table  we  must  first  compute,  by  means  of  Table  III.,  the  anomaly  U,  corresponding  to  the  time  t  from  the  peiihelion,  in  a  parabola, 
whose  perihelion  distance  is  D.  To  this  value  of  U,  we  must  apply  a  correction,  of  the  first  order,  S.  (1  —  f)  ;  first  proposed  by 
Simpson,  and  which  corresponds  to  the  function  [697].  When  1  —  e  is  somewhat  large,  and  great  accuracy  is  required,  we  must  apply 
a  correction  of  the  second  order  B.  (1  —  e)3  ;  first  computed  by  Bessel.  The  logariihms  of  the  values  of  S,  B,  in  se.'iagesimal  seconds, 
are  given  in  Table  IV.,  for  every  degree  of  the  anomaly  U,  with  their  differences;  and  when  any  one  of  these  values  is  negative,  the 
letter  n  is  annexed  to  its  logarithm.  For  intermediate  values  of  U,  we  must  use  the  common  rules  o(  interpolation.  The  logarithms 
of  S  are  given  to  seven  places  of  decimals,  and  those  of  B  to  five  places;  but  in  most  cases  it  will  be  sufficiently  accurate,  if  we  reject 
the  two  last  of  these  ligures.  The  logarithm  of  S,  added  to  the  log.  (1  —  e),  gives  the  logarithm  of  Simpson's  correction;  and  the 
logarithm  of  B,  added  to  2  log.  (1  —  e),  gives  the  logarithm  of  Bessel's  correction.     In  symbols  we  have, 

v=  V'-{-S.{l—e)  +  B  .  (1— e)2;  [In  an  ellipsis]. 

v=U—S.{e  —  l)-i-^  ■  (<:— 1)-;  ['n  a  hyperbola]. 


EXAMPLE. 
We  shall  suppose  that  with  the  lime  t  from   passing  the  perihelion,  and  the  perihelion  distance  D,  the  anomaly  in  a  parabola  is  found, 
by  means  of  Table  III.,  to  be  i!7=  SO"*.     Then  it  is  required  to  find  the  true  anomaly  v  ;  in  an  ellipsis,  whose  excentricity  is  e  =  0,99    ; 
and  in  a  hyperbola,  whose  excentricity  is  e=  1,  01. 


In  an  ellipsis. 

Given  e:=o,gg     and   J7=5o''  to  find  i). 
S        log.     4,383 i7„ 
I  —  e      log.     8,00000 


•  24i  ,6    log.     2,383i7h 


B     log.  3,8341 7« 
(i  —  e)  log.  8,00000 
same       8,00000 


-o*,7  log.  g,824i7„ 


Simpson's  correction, 
Bessel's  correction. 


1/=  5o  00   00  ,0 

—  4   01  ,6 

—  o  ,7 


Tiue  anoTialy  0  =  49    55    57,7 


III  a  hyperbola. 
Given  e  =  i,  01  and  U^  5o   to  find  v. 

The  calculation  of  the  corrections  of  Simpson  and  Bessel,  is  the 
same  as  in  the  ellipsis;  the  only  difference  is  in  the  sign  of  Simpson's 
correction. 

C7'=:  5o'  00'"  00''  ,0 
Simpson's  correction,  -f"         4    01   ,6 

Bessel's  correction,  —  o  ,7 


True  anomaly  »  =  5o  o4    00  ,9 


TABLE   IV. 

To  fiiui  tlio  line  nnomaiy  v,  in  a  very  eccentric  ellipsis  or  hyperbola,  fiom  the  corresponding  anomaly  ?7in  a  parabola  ;   according 
to  Simpsoir.s  inelhoil,  improved  by  Hessel. ^^ 


lO 

II 

12 

i3 
i4 

i5 
i6 

17 
18 

19 

20 
21 
22 

23 

24 

25 

26 

27 
28 

29 

3o 
3i 
3a 
33 
34 

35 
36 
37 
38 

39 

40 
4i 
42 
43 
44 

45 
46 

47 
48 

49 

5o 
5i 

52 

53 

54 

55 
56 
57 
58 

59 
60 


i.ug.  or  s. 

sex.  seconds. 


Infîn.  neg. 

2,g5425,35n 
3,35491,94.1 
3,43o56,98„ 
3,5548g,o5„ 

3,65ioo,44n 
3,72941,16,1 
3,79500,5611 
3,85i66,48n 
3^0 1 30,3971 

3,94536,62n 
3,98488,07,. 
4,02060, 54ii 
4,o53i  1, 8 In 
4,08285,95,. 

4,iioi9,93n 
4, 1 354o,67n 
4,15871,98» 
4,i8o3j,95n 
4,20039,68,1 

4,21905,61» 

4,23642,13,. 

4,2535g,o6n 
4,36764,78„ 
4,28166,46,. 

4,29470,54» 
4,30683,33» 
4, 3 1806,61,. 
4,33847.5o„ 
4,33808,67,, 

4,34693. 32„ 

4.355o3,8i„ 
4,36343,83,, 
4,36912,33,1 
4,37513,93,, 

4, 38049, 1 4n 
4,385iç,o3„ 
4,38924,52,, 
4.39266,33,, 
4,39544,73,, 

4,39760,06,, 
4,3991 3, 36„ 
4,4oooi,i3„ 
4,4ooj6,oi„ 
4,39986,33„ 

4,39881,03,, 
4,39708,93,, 
4.39468,40» 
4,3yi57,gon 
4,38774,94» 

4,383i7,o6» 
4,37781,33,, 
4,37164,40,1 
4,36462,19» 
4,35670,34» 

4,34783,17» 
4,33795,o3„ 
4,33698,74„ 
4,3i486,o8„ 
4,30147.45,, 
4,3867i,76„ 


I'irsl  Dili'. 


Infinite. 

3oo(i6,59 
i7565,o4 
13432,07 

9611,39 

7840,73 
6559,40 
5665,9a 
4963,91 

44o6,23 

3951,45 
3572,47 
325i,27 
2974,14 
2733,98 

25ao,74 
233i,3i 
2160,97 
2006,7^ 

1865,93 

i736,5i 
1616,94 
i5o5,72 
i4oi,68 

i3o4,o8 

1 2 1 1 ,79 

I  I34,3B 

io4o,8g 
961,17 

884,55 

810,59 
739,03 
669,49 
601,61 

535,21 

469,89 
4o5,49 
341,80 
278,41 

2i5,33 

I  52,20 
88,93 
34,83 

—  39,69 

105,39 

172,10 

—  240,53 

—  3 1 o,5o 

—  382,96 

—  457,88 

—  535,74 

—  616,93 

—  703,31 

—  79 '^95 

—  887,07 

—  988,14 

—  1096,39 

1313,66 

—  1 338,63 

—  1475,69 

—  1 636,,  6 


Second  Difl; 


Infin.    neg. 

—  ia5oi,55 

—  5i32,g7 

—  2820,68 

—  1770,67 

—  I28i,3a 

—  893,48 

—  702,01 

—  557,68 

—  454,78 

—  378,98 

—  321, ao 

—  277,13 

—  240,16 

—  2l3,34 

—  189,43 

—  170,34 

—  1 54,34 

—  i4o,8o 

—  139,42 

—  119.57 

Ill  ,32 

—  io4,o4 

—  97,60 

—  92,29 

—  87,51 

—  83,39 

—  79'72 

—  76,63 

—  73,96 

—  7>,57 

—  69,53 

—  67,88 

—  66,4o 

—  65,33 

—  64,4o 

—  63,69 

—  63,39 

—  63 ,08 

—  63.i3 

—  63,28 

—  64,09 

—  64,52 

—  65, 60 

—  66,81 

—  68,43 

—  69,97 

—  72,46 

—  74.92 

—  77.86 

—  81,, 

—  85,29 

—  89,74 

—  95,12 

—  101,07 

—  108, 1 5 

—  116,37 

—  I35,g 

—  1 37,06 

—  i5o,37 


l^ug,  of  B. 


Infin.  neg. 

2,o5ig4» 
3,35333,1 
2,53oog„ 
2,656 10,1 

2, 75450,, 
a, 8356 1,1 
2,90473» 
2,9651 3» 
3,01903» 

3,o6777„ 
3,1  i24o„ 
3,1 5364,, 
3,19205,, 
3,228o5„ 

3,36198,, 
3,3940g,, 
3,33458,, 
3,35365„ 
3,38i42„ 

3,4o8oo„ 
3,43348^ 
3,45794» 
3,48 i46„ 
3,5o4o7« 

3,5258i„ 
3,54673,, 
3,56684„ 
3,586ig„ 
3,6o479„ 

3,62264,, 
3,63o76„ 
3,656 17,, 
3,67187,, 
3,68685,, 

3,701 13„ 
3,71473,, 
3,72758,, 
3,73g7i,, 
3,75  no» 

3,76174» 
3,77 165„ 
3,78080» 
3, 78g 1 9» 
3,79679" 

3,8o356„ 
3,80949» 
3,8 1 454» 
3,81870» 
3,82194» 

3,82417» 
3,82538» 
3,82548,, 
3,82445/1 
3,83220» 

3,8i863» 
3,81 365,, 
3,807 1 3« 
3,7g8g7» 
3,78897» 
3,77695» 


Infin. 

3oi39 
1 7676 
12601 

9840 

8111 
6912 
6o4o 
53go 

4874 

4463 
4ia4 
384 1 
3600 

3393 

331  I 

3o4g 
3907 

2777 

2658 

2548 
3446 

3353 

2361 

2174 
2091 

3012 

1935 

i860 

1785 

I7I2 
i64i 
1570 
i4g8 

1428 

i35g 
1286 

I2l3 

II 39 

1064 

991 
9i5 
83g 
760 

677 

593 
5o5 
4i6 
324 

223 


—  io3 

—  235 

-357 


—  653 

—  816 
— 1000 

— 1303 

—  1438 


60 
61 
63 

63 
64 

65 
66 

67 
68 

69 

70 
71 
72 
73 
74 

75 

76 

7 

78 

79 

80 
81 
83 
83 
84 

85 
86 

87 


90 
9' 
9' 
93 
94 

95 
96 
9- 
9i 
99 

100 
101 
103 
io3 
io4 

io5 
106 


109 

ITO 
1  I  1 
113 

ii3 

ii4 

ii5 
116 

117 
118 

"9 


i.i.g.  or  «. 

sex.  seconds 


4,28671,76. 
4,37045,70. 

4,35a53,4on 
4,33375,93. 

4,21090,35» 

4,1 8668,38. 
4,15974,94» 
4,1 2965,58. 
4,og582,g6„ 
4,o575i,66, 

4,01 368 ,88. 
3,g639i,i  1. 
3,90307,53. 
3,83ogi,43n 
3,74094,99» 

3,62292,660 
3,45382,45. 
3,16757,57» 
0,87017,73. 
3,16902,43 

3.47716,74 
3,65978,86 
3,79098,67 
3,89400,55 
3,979 '7.62 

4,o53oi,79 
4,1  i582,oi 
4,17270,58 
4,23412,29 
4,371 1 1,80 

4.3i443,5i 
4,35465,59 
4.3g325,36 
4,43757,53 
4,46ogo,g5 

4,4925o,5i 
4,53354,88 
4,55120,92 
4,57862,82 
4,60492,71 

4,63020,78 
4,65456,52 
4,67807,55 
4,70080,97 
4,72283,19 

4,74419,74 
4,76495,65 
4,785 1 5,45 
4,8o483,28 
4,82402,87 

4,84277,69 
4,86110,88 
4,87905,38 
4,89663,98 
4,9 1389, 1 3 

4,93083,36 
4,94748,58 
4.96387,30 
4,98001,1 1 
4,99593,23 
5,01 162,34 


1626,06 
1792,30 

-  1977.47 

-  2i85,58 

242 1 ,97 

2693,44 
3009,36 

-  3383,63 

-  383i,3o 

-  4382,78 

-  5077,77 

-  5983,59 
7216,09 

-  8996,44 

-  11802,33 

-  i6gio,2 

-  28634,88 
-2,39739,84 

3o8i4,3i 

18262,12 

i3i  ig,8i 

io3oi,88 

8517,07 

7284,17 
638o,23 
5688,57 
5i4i,7i 
46gg,5i 

4330,71 

4o33,o8 
375g,67 
3532,37 
3333,43 

3i5g,56 

3oo4,37 
2866,04 
2741,90 
2629,8g 

2528,07 

2435,74 
235i,o3 
2273,43 
2202,33 

2i36,55 

2075,91 
2019.80 
1967,83 
igig,5ci 

1874,82 

1833,19 
i794,5o 
1758,60 
1725,15 

i6g4,i3 

i665,32 
I 638 ,63 
1613,91 
1 59 1 , 1 3 
1 570, 1 1 
i55o.gi 


Second  Dili'. 


-  i5o,37 

-  166,24 

-  185,17 

-  208,11 

-  236,3g 

-  271,47 

-  3i5.g2 

-  373,26 

-  448,68 

-  55i,48 

-  694,99 

-  905,82 
-1232. 5o 
-i78o;35 
-2805,89 


— 5i42,3i 

—  2817,93 

—  1784,81 

—  i233,go 

—  9"3,95 

—  6gi,65 

—  546,86 

—  443,30 

—  368,8o 

—  307 ,63 

—  263,4 1 

—  237,40 

—  198,85 

—  173,86 

—  155,19 

—  1 38,33 

—  124,14 

—  112,01 

—  101,82 

—  92,33 

—  84,71 

—  77,61 

—  71,20 

—  65,67 

—  60,64 

—  56,11 

—  51,97 

—  48,24 

—  44,77 

—  4i,63 

—  38. 6g 

—  35,90 

—  33,45 

—  3 1, 02 

—  28,81 

—  26,70 

—  24,71 

—  22,79 

—  2 1 ,0 1 

—  19.20 


..r  B. 

fconds. 


3,776g5„ 
3,76267,, 
3,7458i„ 
3,72602,, 
3,70282,, 

3,6756i„ 
3,64354» 
3,6o555n 
3,56oo7n 
3,5o47i,„ 

3,4357g„ 
3,347o5„ 
3,22612,, 
3, 043 5 1 
2,68g54n 

2,2 1  £60 
2,g34i7 
3,3f)257 
3,37493 
3,5o38o 

3,60770 
3,69533 
3,771 54 
3,83938 
3,90043 

3,9563o 
4,00782 
4,o558o 
4,10078 
4,i43i4 

4,i8325 

4,23  I  39 
4,35765 

4,2g244 
4,32585 

4,35799 
4,3889a 
4,41887 
4,44786 
4,47599 

4,5o333 
4,52993 
4,55585 
4,58 116 
4,6o5gi 

4,63oi3 
4,65383 
4,67711 
4,6999g 
4,72248 

4,74463 
4,76647 
4,78803 
4,8og3o 
4,83o36 

4,85i3i 
4,87189 
4,89242 
4,91281 
4,g33o8 
4,g532g 


-  142B 

-  1686 

-  '979 

-  2320 

-  2721 

-  3207 

-  3799 

-4548 

-  5536 

-  68g2 

-  8874 
-i2og3 
-18261 
-35397 


+71557 
26840 
17235 
12888 

10390 

8763 
7621 
6774 
6114 

5588 

5i52 
4798 
4498 
4236 

401 

38o4 
3636 
3479 
334i 

32i4 
3093 
2995 
2899 
2813 

2734 

2659 
25g3 
253i 
2475 
2421 
237. 

2328 

2288 
2249 

22l5 
2184 

2i55 
2138 
2106 

2o85 

2068 
2o53 
2039 
2027 
ao2i 
201 5 


TABLE   IV. 

To  find  the  true  anomaly  «,  in  a  very  eccentric  ellipsis  or  liyperbola,  from  the  corresponding  anomaly  17  in  a  parabola  ; 
accordini;  to  Simpson's  method,  improved  by  Bessel. 


U. 


d 
1 20 
121 
122 

123 

124 

125 

126 

127 
128 
129 

i3o 
i3i 

l32 

i33 

1 34 

i35 

1 36 

1 37 
i38 
139 

i4o 
i4r 

l42 

143 

i44 

i45 
1 46 

l47 

148 
149 

i5o 
i5i 

l52 

1 53 

1 54 

i55 

1 56 

1 57 

1 58 
159 

160 
161 
162 

1 63 

1 64 

i65 
166 
167 
168 
169 

170 

171 
172 
173 
174 


sex.    seconds 


5,01162,34 
5,02713,25 
5,04246.44 
5,05763,87 
5,07266,81 

5,08757,06 
5,10235,87 
5,11705,01 

5,i3i65,35 
5,14618,91 

5,16066,94 
5,17510,76 
5,18952,15 
5,20392,32 
5,2i832,5o 

5,23274,66 
5,24719,89 
5,26170,05 
5,27626,64 
5,29091,30 

5,3o565,78 
5,32o5i,87 
5,3355i  43 
5,35o66,42 
5,36598,87 

5,38i5i,i7 
5,39725,43 
5,4 1 324,24 
5,42950,27 
5,44606,4 1 

5  46295,75 
5,48021,66 

5,49787,97 
5,5 1 598,58 
5,53458.03 

5,55371,25 
5,57343,74 
5,59381 ,69 
5,61492,02 
5,63682,66 

5,65962,52 
5,68341,99 
5,70833,00 

5,73449,49 
5,76207,92 

5,79127,92 
5,82233,12 
5,85552,33 
5,89121,30 
5,92985,02 

5,97201,42 
6,01 846,63 
6,07023,80 
6,12877,42 
6,19619,12 


175  6,27576,94 

176  6,37300.24 
[77  6,49819,30 

178  6,67546,42 

179  6,97560. [8 

180  Infinite 


1 550,91 
i533,iQ 
■  5i7,43 
1 502,94 

1490,25 
1478,81 
1469,14 
1460.34 
1453^56 

i448,o3 

1443,82 
1441,39 
1440,17 
i44o,i8 

1442,16 

i445,23 
i45o,!6 
1456,59 
1464,66 

i474,48 

1486,09 
i4g9,56 
i5i4,99 
i532,45 

i552,3o 

1574,26 
1598,81 
1626,03 
1 656, 1 4 

1689,34 

1725,9 
1766,3. 
1810,61 
1859,45 

1913,22 

1972,49 
2037, g5 
2110,33 
2 1  go,64 

2279,86 

2379,47 
2491,01 
2616,49 
2758,43 

2920,00 

3io5,2o 
33i9,2i 
3568,97 
3863,72 

4216,40 

4645,21 
5i77,i7 
5853,62 
674 1 ,70 

7957,82 

9723,30 
12519,06 
17727,12 
3oo  13,76 
Intinite 


Seeond 
Ditr. 


—  17,72 

—  15,76 

—  14,49 

—  12,69 

—  11,44 

—  9-67 

—  8,80 

—  6,78 

—  5,53 

—  4,21 

—  2,43 


+ 


1,22 
0,01 

1,98 
3,07 
4,93 
6,43 
8,07 

9,82 
11,61 

i3,47 
i5,43 
17,46 
19,85 
21,96 

24,55 
27,22 
3o,ii 

33,20 
36,57 
4o,4o 
44, 3o 


53,77 
59,27 

65,46 
72,38 
80,3 1 

89,22 
99,61 
1 1 1 ,54 
125,48 
i4i,94 
161,57 
i85,2o 

2l4,01 
249,76 
294,75 

352,68 

428,81 

531,96 
676.45 
888,08 

1216,12 
1765,48 
2795,76 
5208,06 
12286.64 
Infinite. 


Lo;.  of  «. 
sex.seLOnds. 


4,9532g 
4,97344 

4,gg355 
5,01 36 
5,03379 

5,05395 
5,07419 
5,09451 
5,1 1496 
5,i3556 

5,1 5634 
5,17734 
5,ig855 
5,22004 
5,24182 

5,26395 
5,28649 
5.3o()4i 
5,33278 
5,35664 

5,38io6 
5, 4061 1 
5,43 1 80 
5,45821 
5,48539 

5,5i34i 
5,54236 
5,57230 
5.6o33i 
5,63547 

5,66893 
5,70375 
5,74010 
5,77806 
5,81781 

5,85948 
5.90332 
5,94946 
5,gg8i6 
6,04965 

6,10426 
6,16232 
6,224i4 
6,29016 
6,36 1 11 

6,43737 
6,51976 
6,60914 
6^70666 
6,81 364 

6,93190 
7,06371 
7,21220 

7,38173 
7,57867 

7.81288 
8,ioo85 
8,47350 
9,00022 


201 5 
201 1 
2012 
2012 

2016 

2024 

2o32 

2045 
2060 

2078 

2100 
2121 
2149 
2178 

22l3 

2254 
2292 
2337 

2386 

2442 

25o5 
2569 
2641 
2718 

2802 

2895 
2gg4 
3ioi 
3216 

3346 

3482 
3635 
37g6 
3975 
4167 

4384 
46i4 
4870 
5i4g 
5461 

58o6 
6182 
6602 
7og5 

7626 

8239 

8938 

9752 

10698 

11826 

i3i8i 
i484q 
16953 
19694 
23421 

28797 
37265 
52672 


In  the  extreme  and  middle  parts  of  the  table, 
the  first  differences  vary  rapidly,  in  which  case 
we  may  use  the  valuer,  of  .S',  i>,  instead  of  tiieir 
logarithms,  as  in  the  following  auxiliary  table. 

AUXILIARY  TABLE  IV. 


Î7. 

s. 

sex.  seconds. 

Diff. 

B. 

sex.  seconds. 

Diff. 

d 
0 
1 
2 
3 

4 
5 

70 
7' 
72 
73 
74 

75 
76 

77 
78 

79 

80 
81 
82 

s 

—  0,0 

—  900.0 

—  1798:5 

—  26g5,o 

—  3588,3 

—  4477,2 

—  55o7,4 

—  4iq6,9 

—  2843,3 

—  1470,9 

—  7,4 
1475,8 

3ooo,3 
4568,7 
6i8o,c 

—  goo,o 

—  8g8,5 

—  896.5 

—  893,3 

—  888,9 

1 3 10.5 

1 353.6 
1372,4 
i463,5 
i483,2 

i524,5 

1 568,4 
1611,3 

s 

—  0,0 

—  II2.7 

—  225,6 

—  338,9 

—  453,0 

—  568,2 

—  2727,7 

2223,6 

—  i683,i 

—  iio5,4 

—  489,3 

1 65, 4 

85q,3 

1594,3 

2370,9 

—  112,7 

—  112,9 

—  ii3  3 

—  ii4,i 

—  Il5,2 

5o4,i 
540,5 

577,7 
616,1 

654,7 

693,9 
735,0 
776,6 

TABLE  V. — For  an  Ellipsfs. 

Tliis  table  is  to  be  used  in  finding  the  true  anomaly  v,  currespomling  to  the  time  t  from  the  perihelion,  in  a  very 
excentrical  ellipsis  ;  the  cxcentricity  e  and  the  perihelion  distance  D  being  given.  In  paint  of  accuracy,  it  is  not  restricted  to 
the  tirst  and  second  powers  of  1  — e,  lilic  Tal)le  IV.,  but  includes  all  llie  power.-*  of  tliat  quantity.  Tliis  table  is  nearly  in  the 
same  form  as  it  was  first  given  by  Professor  Gauss. 

Rl-le.    From  e  find  a=l  —  e,    a'- =  0,1  +  0,9  .  f,  and  then  find  the  approximate  value  of  log.  (',  by  the  following  formula; 

Appiox.  log.  i'=log.  (-j-log.  a.'  —  2^.  log.  £). 
With  this  value  of  ('  find  the  corresponding  value  of  t'iu  Table  III.  ;  also, 

log.  /3  =  log.  a  +  arith.  log.  co.   a'^  -j-  9,6939700  —  10,0000000  ; 
Approx.  log.  .1=  log.  /2-(-2  log.  tang.  ^  C. 
Entfir  Table  V.,  with  the  natural  number  corresponding  to  this  value  of  log.  j9,  and  find  the  corresponding  log.  S,  which  is  to 
be  subtracted  from  the  approximate  log.  ('  to  obtain  the   corrected  value  of  log.  t'.     With  this  corrected  value  find,  in  Table 
III.,  the  corrected  value  of  U,  and  for  the  sake  of  distinction,  we  shall  represent  it  by  w  ;   then  the  corrected  value  of  log.  Ji 
is  found  by  the  following  formula,  which  is  similar  to  the  preceding  one,  changing  {/into  w ; 

Correct,  log.  Jl  =  log.  /3  -)-  2  log.  lang.^  w. 

It  will  very  rarely  be  necessary  to  repeat  again  this  operation  to  get  a  more  accurate  value  oi  A  ;  we  may  therefore,  with  this 
value  of  ^,  find  the  correct  value  of  C,  in  Table  V.,  and  then, 


tang.a  4  ti  = 


.4 


C  —  0,i 


.Î  ■  1  — e  ' 


■0,8.^ 


JO  .  sec.a  è  V. 


[Anomaly  v]. 


[Radius  vector  r]. 


C  +  0,2.^ 

We  may  observe  that  in  computing  a  large  number  of  observations,  it  will  frequently  happen  that  the  value  of  Bis  very  nearly 
known,  at  the  commencement  uf  the  operation  ;  in  this  case  the  correction  B,  may  be  applied  to  the  first  process,  in  finding  the 
approximate  value  oJ  t'. 


EXAMPLE. 


Given  the  excentricity  «  =  0,96764567  ;  log.  perihelion  distance  i3  =  9,7656500;  f  =  63''''^^544  ;  to  find  d  and  ; 
From  the  value  of  e  we  get,  a=i — e=:o,o3235433;  a'2  =  0,1  4-0,9  6^0,970881103. 


t  =  63"'*y',544 


Approximate  Operation. 

a'2^o,i +0,9  .  e  log. 

a'  log. 

D  log.  CO. 

its  half 
log. 

Approx.  log.  t' 

Hence  U  =  gQ6'',  in  Table  III. 
a=  1  —  e  log. 

a'2  log.  CO. 

Constant  log. 

Sum  gives  /3       log. 
.i  Î7=49''33"  tang. 

same 

Approx.  .4  =  0,022923  log. 

Corresponding  log.  B=o,ooooo4o,  Table  V. 


9,9871661 

9,9935830 
o, 2343500 
0,1171750 
i,8o3o745 


2,1481825 

8,5o993a5 
0,0128339 
9,6989700 


8,2217364 

0,06927 

0,06927 


8,36027 


a23 


Corrected  Operation. 


Subtract  log.  £  :=  o,ooooo4o  gives  correct  log.  (' 
Hence  U  or  u;  =  99'' 6°*  1 3',  4  in  Table  III. 


i  10  =  49'' 33"  6',  7 
Corrected  Jl  =  0,0229361 


same 

tang, 
same 

log. 


log. 


2,1481785 


8,2217364 

0,0692972 
0,0692972 

8,36o33o8 


0,8  JÎ  =  0,01 83409 

. 

C  =;  1 ,0000242 

log.  CO. 

• 

C  — 0,8.^  =  0,9816833 

0,0080286 

I  +«=1,96764547 

log- 

0,293946g 

I— e  =  a 

log.  CO. 

1,4900675 

Sum  is 

2  log. 

tang.  4  V 

0,1523738 

4  0  :=    5o   0    0,1 

tang. 

0,0761869 

d    m    t 

»=  too  0   0,2 

C  +  0,2  JÎ  =  1 ,0046094 

log.  CO. 

9,9980028 

C  — 0,8  jî  =  0,981 6833 

log. 

9,9919714 

D 

log. 

9,76565oo 

io  =  5o''o°'o',i 

sec. 

0,1919327 

aame 

0,1919327 

0,1394896 


TABLE    V.  —  For  an  Ellipsis. 

In  the  inverse  problem,  we  have  given,  the  true  anomaly  v,  the  perihelion  distance  O,  and  the  excentriciiy  e,  to  find  the  time 
t  from  the  perihelion  in  days.     This  is  obtained  by  the  following  rule. 


Rule.    With  e  and  »  find  T  = 


1  — e 

1+e 


.  tang.3  J  11,  and  then  by  Table  V.,  the  corresponding  value  of  C.     Also, 


Log.  A=  log.  T-f  log.  C  -Y  arith.  comp.  log.  (1  -f-  0,8  .  T)  ; 
from  which  we  find  log.  B,  by  means  of  Table  V.     Then  we  find, 

log.  ij  =  2,0654486  +  J  log.  2)  +  i  log.  ./Î  +  log.  5  —  è  log.  (1  —  e)  ; 
log.  <2  =  log.  <i  +  8,8239087  +  log.  A  -\-  log.  (1  -f  9  <■)  —  log.  (1  —  c)  ; 
'=',  +  '2- 


EXAMPLE. 
Given  as  before  «  =  0,96764567;  log.  perihelion  distance  X)  =  9,7656500  ;  and  the  true  anomaly  »^  100'' o^o',  2  ;  to  find  the 
time  (  from  the  perihelion  in  days. 


I  —  e 

4  0  ^  5o  o""  o  ,  I 


T  =  0,0233539 
Hence  C=  1,0000242  Table  V 
1-1-0,8T=  i,oi8683r 

.4=  0,0229261 
Corresponding  log.  B  in  Table  V. 


log- 

8,5099325 

log.  CO. 

9,706053 1 

tang. 

0,0761869 

same  tang. 

0,0761869 

log. 

8,3683594 

log- 

0,00001  o5 

log.  CO. 

9,9919609 

log. 

8,36o33o8 

o,ooooo4o 

:  43"'^J'%564 


-^dftyg 


<2=i9""'%98o 
,,4-,2  =  63''»>-S544  =  ( 


Constant  log. 
t log.  D 
è  log.  Jl 
log.  B 
J  log.  (i  — e)  arith.  co. 

log. 
Constant 

A   log. 

+  9  «  =  9,7088110  log. 

(i  —  e)  log.  CO. 

log. 


2,0654486 
9,6484750 
9,1 801 654 
0,0000040 
o,745o337 

1,6391267 
8,8339087 
8,36o33o8 
0,9871661 
1 ,4900675 

i,3oo5gg8 


Lo<j.  B 


0,000 
001 
002 

00  3 
004 

o,oo5 
006 
007 
oo3 
009 

0,010 
oil 

012 
oi3 
oi4 

0,0 1 5 
016 
017 
018 
019 

0,020 
021 
022 
023 
024 

0,025 
026 
027 
028 
029 

o,o3o 
o3i 

032 

o33 
o34 


o,o35 
o36 
o37 
o38 
039 

o,o4' 


0,0000000 
000 
000 
001 
001 

0,0000002 
oo3 
oo4 
oo5 
006 

0,0000007 
009 
oil 
oi3 
oi5 

0,000001 7 
019 
022 
024 
027 

o,ooooo3o 
o33 
o36 
o4o 
043 

0,0000047 
o5i 
o55 
oSg 
o63 

0,0000067 
072 
077 
082 
087 

0,0000092 
097 
io3 
108 
ii4 

0.0000120 


1 ,0000000 
1 ,0000000 
1,0000002 
1 ,0000004 
1 ,0000007 

1 ,00000 1 1 
1,0000016 
1,0000022 
1,000002g 
1,0000037 

1 ,0000046 
I  ,ooooo56 
1 ,0000066 
1 ,0000078 
1 ,0000090 


0,00000 
0,00100 
0,00200 
o,oo3oi 
o, 00401 

o,oo5o2 
o,oo6o3 
0,00704 
o,oo8o5 
0,00907 

0,01008 
0,01110 
0,01212 
o,oi3i4 
o,oi4i6 


i,ooooio3  o,oi5i8 
i,oooon8  0,01621 


1,0000 1 33 
1,0000149 
1,0000166 

1,0000184 

1,0000203 

1,0000223 
1 ,0000244 
1 ,0000265 

1 ,0000288 
1  ,oooo3 1 2 
i,oooo336 
1, 0000362 
I  ,oooo388 

1, 00004 16 
1 ,0000444 
1 ,0000473 
i,oooo5o3 
i,oooo535 

1 ,0000567 
1 ,0000600 
1 ,0000634 
1 ,0000669 
1 ,0000704 
1 .000074 1 


0,01723 
0,01826 
0,01929 

O,02o32 

0,021 36 
0,02239 
0,02343 
0,02447 

o,o255i 
0,02655 
0,02760 
0,02864 
0,02969 

o,o3o74 
o,o3i79 
0,03284 
0,03389 
0,03495 

o,o36oi 
0.03707 
o,o38i3 
0,03919 

O,o402  5 

o,o4i  32 


Lo£.  B 


o,o4o 
o4i 
042 
o43 
044 

0,045 
o46 
o47 
048 
049 

o,o5o 
o5i 
o52 
o53 
o54 

o,o55 
o56 
o57 
o58 
059 

0,060 
061 
062 
o63 
064 

o,o65 
066 
067 
068 
069 

0,070 
071 
072 
073 
074 

0,075 
076 
077 
078 
079 

0,080 


0,0000120 
126 
i33 
139 

i46 

0,00001 52 
i59 
166 
173 
18 

0,0000181 
196 
204 
212 
220 

0,0000228 
236 
245 
254 
263 

0,0000272 
281 
290 
3oo 
309 

o,oooo3i9 
339 
339 
35o 
36o 

0,0000371 
38 1 
392 
4o3 
4i5 

0,0000426 
437 

449 
461 
473| 
0,000048 5 1 


1 ,000074 1 
1 ,0000779 
1 ,00008 1 8 
i,oooo858 
1 ,0000898 

1 ,0000940 
1,0000982 
1,0001026 
1,0001070 
1,0001116 

1,0001163 
1,0001210 
1,0001258 
1 ,000 1 307 
1, 0001 358 

1,0001409 
1, 000 1 461 
i,oooi5i4 
1,0001 568 
1,0001623 

1,000167g 
1,0001736 
1 ,000 1 794 
1,0001853 
1,0001913 

1,0001974 
i,ooo2o36 
1,0002099 
1,00021 63 
1,0002228 

1,0002394 
1, 0002360 
1,0002428 
1 ,0002497 
1,0002567 

1 ,0002638 
1,0002709 
1,0002782 
1 ,0002856 
1 ,0002930 
1  ,ooo3oo6 


o,o4i3ig 
0,042387 
0,043457 
0,044528 
o,o456oi 

0,046676 
0,047753 
o,o4883i 
0,0499 1 1 
0,050993 

0,052077 
o,o53i63 
o,o5425o 
0,055339 
o,o5643o 

0,057523 
o,o586i8 
0,059714 
0,060812 
0,061912 

o,o63oi4 
0,064 1 18 
o,o65223 
o,o6633i 
0,067440 

o,o6855i 
0,069664 
0,070779 
0,071896 
0,073014 

0,0741 35 
0,075257 
0,076381 
0,077507 
0,078635 

0,079765 
0,080897 
o,o82o3o 
o,o83i66 
o,o843o3 
o,o85443 


0,080 
081 
082 
o83 
084 

o,o85 
086 
087 
088 
089 

0,090 
091 
092 
093 
094 

0,095 
096 
097 
098 
099 

0,100 
101 
102 
io3 
1 04 

o,io5 

106 
107 
108 
109 

0,1 10 
11 1 

113 

II 

114 


0,1 15 
116 
117 
ii8 

i'9 
0,120 


Los.  B 


0,00004 
4_ 
5io 
523 
535 

o,oooo548 
56 1 
575 
588 
602 

0,000061 5 
629 
643 
658 
672 

0,0000687 
701 
716 
73i 
746 

0,0000762 

777 
793 
809 
825 

0,0000841 

857 
873 
890 
907 

0,0000924 

94 
958 

975 
993 

0,000101 
1029 
io47 
io65 
io83 

0,0001102 


,ooo3oo6 
,ooo3o83 
,ooo3i6o 
,0003239 
,ooo33i9 

,0003399 
,ooo348i 
,ûoo3564 
,ooo3647 
,0003732 

,ooo38i8 
,0003904 
,0003993 
,ooo4o8 1 
,ooo4 1 70 

,0004261 
,0004353 
,0004446 
,0004539 
,ooo4634 

,0004730 
,0004826 
,0004924 
,ooo5o23 
,ooo5 123 

,ooo5224 
,ooo5325 
,0005428 
,ooo5532 
,ooo5637 

,0005743 
,ooo585o 
,ooo5g58 
,0006067 
,0006177 

,0006288 
,0006400 
,00065 1 3 
,0006627 
,0006743 
.0006858 


o,o85443 
o,o86584 
0,087737 
0,088872 
0,090019 

0,091168 
0,092319 
0,093472 
0,094627 
0,095784 

0,096943 
0,098104 
0,099266 
0,1 0043 1 
0,101598 

0,102766 
0,103937 
o,io5i  10 
0,106284 
o,  1 0746 1 

0,108640 
0,109820 
0,1 1  ioo3 
0,112188 
0,1 13375 

0,1 1 4563 
0,115754 
0,116947 
0,1 18142 
0,119339 

O,i2o538 
0,131739 
0,122942 
o, 124148 
0,125355 

0,126564 
0,127776 
0,138989 

O,l3o3o5 

o,i3i423 
0,132643 


TABLE    v.  — For  an  Ellipsis. 


To  find  the  true  anomaly 

n  a  very  excentric  elli 

psis,  by  th 

J  method  of  Gauss 

A 

Log.  B 

c 

T 

A 

Log.  B 

c 

T 

A 

Log.  B 

c 

T 

0,120 

0,0001102 

i,ooo6858 

o,i32643 

0,180 

0,00025 1 5 

1,0016764 

0,209894 

0,240 

0,0004537 

1 ,0028644 

0,296980 

121 

1121 

1 ,0006976 

0,1 33865 

181 

2543 

1,0016945 

0,211253 

241 

4576 

i,oo288g4 

0,297498 

122 

1.39 

1 ,0007094 

0,135089 

182 

2672 

1,0016128 

0,212614 

24j 

461 5 

i,oo2gi46 

0,299018 

123 

ii58 

1,0007213 

o,i363i5 

i83 

2601 

i,ooi63ii 

o,2i3g77 

243 

4664 

1 ,0039397 

o,3oo542 

124 

1 178 

1 ,0007334 

0,137543 

184 

263o 

1,0016496 

0,2 15343 

244 

4694 

1,0039651 

o,3o2o68 

0,125 

0,0001197 

1,0007455 

0,i38774 

o,i85 

0,0002660 

1,0016682 

0,216712 

0,245 

0,0004734 

I  ,oo3g9o5 

o,3o35g7 

126 

1217 

1,0007577 

0,140007 

186 

2689 

1,0016868 

o,2i8o83 

246 

4774 

i,oo3oi6i 

o,3o5i39 

127 

1236 

1,0007701 

o,i4i34i 

18-- 

2719 

1,0017067 

0,219466 

247 

48i4 

i,oo3o4i8 

o,3o6664 

128 

1256 

1,0007825 

0,142478 

188 

2749 

1,0017246 

0,220832 

248 

4864 

1 ,0030676 

0,308202 

129 

1276 

1,0007951 

0,143717 

189 

2779 

1,0017436 

0,222211 

249 

4894 

1 ,0030936 

0,309743 

0,1 3o 

0,0001206 

1 ,0008077 

0,144959 

0,190 

0,0002809 

1,0017637 

0,223692 

0,260 

0,0004936 

1,0031196 

0,3 1 1286 

i3i 

.3.7 

1,0008205 

0,146202 

19' 

283q 

1,0017830 

o,2  24g75 

261 

4976 

i,oo3i458 

o,3i2833 

l32 

1337 

i,ooo8334 

0,1 47448 

192 

2870 

i,ooi8oi3 

o,33636i 

263 

5017 

1, 0031721 

o,3i4382 

1 33 

i358 

i,ooo8463 

0,148695 

193 

2900 

1,0018208 

0,337760 

263 

6o58 

1,0031986 

0,316935 

1 34 

1378 

1,0008594 

0,149945 

194 

3931 

1, 0018404 

0,229141 

264 

5099 

1, 0032260 

0,3 17490 

0,1 35 

0,000139g 

1 ,0008736 

o,i5ii97 

0,195 

0,0002963 

1,0018601 

o,23o535 

0,255 

o,ooo5i4i 

1,0032617 

0,3 1 9048 

1 36 

1421 

1 ,0008859 

o,i53452 

196 

2993 

1,001879g 

o,33i93i 

256 

5182 

1,0032784 

0,320610 

1 37 

i442 

1 ,0008993 

0,1 53708 

197 

3o25 

i,ooi8gg8 

0,233329 

267 

6224 

1  ,oo33o53 

0,322174 

1 38 

1463 

1,0009128 

0,154967 

198 

3o56 

1, 001  g 198 

o,23473i 

258 

6266 

1, 0033323 

0,323741 

■  39 

1 485 

1 ,0009264 

0,156228 

199 

3o88 

i,ooig4oo 

o,336i35 

269 

53og 

1,0033596 

o,3253i2 

o,i4o 

0,0001 5o7 

i,ooog4oi 

0,167491 

0,200 

O,0003l2O 

i,ooig6o2 

0,237641 

0,260 

o,ooo535i 

1,0033867 

0,326885 

i4i 

l52Q 

1 ,0009539 

0,1 58756 

201 

3i53 

1,0019806 

0,338960 

261 

6394 

i,oo34i4i 

0,328461 

142 

i55i 

1 ,0009678 

0,160024 

203 

3i84 

1,0020011 

o,24o36i 

262 

5436 

i,oo344iG 

o,33oo4i 

i43 

1573 

1,0009819 

0,161294 

2o3 

3216 

l,OC'>02I7 

0,24177c 

263 

5479 

i,oo346g2 

o,33i623 

144 

1596 

1 ,0009960 

0,162566 

204 

3249 

1,0020424 

0,243193 

264 

5533 

I  ,oo34g7o 

0,333208 

0,145 

0,0001618 

1,0010103 

o,i6384o 

o,2o5 

0,0003282 

1, 0020632 

0,344612 

0,266 

o,ooo6566 

1,0036248 

0,334797 

i46 

i64i 

1,0010246 

o,i65i  16 

206 

33i5 

1 ,0020842 

0,246034 

266 

66og 

1,0036628 

o,336388 

1 47 

1664 

1,0010390 

0,166395 

207 

3348 

1,0021062 

0,347468 

267 

5653 

1  ,oo358og 

0,337983 

1 48 

1687 

i,ooio536 

0,167676 

208 

338i 

1,0021264 

0,248885 

268 

56g7 

1,0036091 

0,339680 

149 

1710 

1, 00 10683 

0,168969 

209 

3414 

l,oo2i477 

o,25o3i6 

26g 

5741 

1 ,0036376 

0,341181 

0,1 5o 

0,0001734 

I,ooio83o 

0,170345 

0,210 

o,ooo3448 

1,0021690 

0,261748 

0,270 

0,0006786 

1 ,0036669 

0,342786 

i5i 

1757 

1,0010979 

0,171533 

211 

3482 

i,oo2igo5 

o,253i83 

271 

682g 

i,oo36g45 

0,344392 

l52 

1781 

1,0011 129 

0,172823 

212 

35i6 

1,0022122 

0,354620 

272 

5874 

1,0037232 

0,346002 

1 53 

i8o5 

1,0011280 

0,1741 15 

2l3 

355o 

1,0022339 

0,266061 

273 

^919 

1,0037621 

0,347615 

i54 

1829 

1,0011432 

0,175410 

214 

3584 

1 ,0022567 

0,267604 

274 

5964 

1,0037810 

0,349231 

o,i55 

0,0001854 

1,0011 585 

0,176707 

0,2  I  5 

o,ooo36i8 

1,0022777 

o,268g5o 

0,276 

0,000600g 

i,oo38ioi 

o,35o85o 

1 56 

1878 

1,0011739 

0,178006 

216 

3653 

i,oo229g8 

0,360398 

276 

6064 

i,oo383g3 

0,362473 

1 57 

1903 

1,0011894 

0,179308 

217 

3688 

1,0023220 

0,361849 

277 

6100 

i,oo38686 

0,354098 

1 58 

'927 

I,001205l 

0,180612 

218 

3733 

1,0023443 

o,2633o3 

278 

6145 

1,0038981 

0,355727 

.59 

1952 

1, 00 1 2 208 

0,181918 

219 

3758 

1 ,0023667 

0,264769 

279 

6191 

1 ,0039277 

o,35736g 

0,160 

0,0001977 

1, 001 2366 

0,183336 

0,220 

0,0003793 

1,0023892 

0,366218 

0,380 

0,0006337 

1,0039673 

o,368g94 

161 

2003 

1,0012526 

0,184537 

231 

383g 

1,0024119 

0,267680 

281 

6283 

1,0039873 

o,36o632 

162 

2028 

1 ,00 1 2686 

o,i8585o 

222 

3865 

1,0024347 

0,269145 

282 

633o 

1,0040171 

0,363374 

1 63 

2o54 

1,0012848 

0,187166 

223 

3900 

1,0024576 

0,270613 

283 

6376 

1,0040472 

0,363918 

164 

2080 

i,ooi3oi  I 

o,i88484 

224 

3g36 

1 ,0024806 

0,273083 

284 

6423 

1,0040774 

o,365566 

0,1 65 

0,0002106 

i,ooi3i75 

0,189804 

0,225 

0,0003973 

1,0026037 

0,273555 

0,286 

0,0006470 

1,0041077 

0,367217 

166 

2l32 

1,00 1 3340 

0,191137 

226 

4009 

1,0026269 

0,276031 

286 

6617 

i,oo4i38i 

0,368871 

167 

2i58 

i,ooi35o6 

0,193453 

227 

4o46 

I,0025502 

0,276609 

287 

6664 

1,0041687 

0,370629 

168 

2184 

1,0013673 

0,193779 

228 

4082 

1,0026737 

0.277990 

288 

6612 

i,oo4i9g4 

0,373189 

169 

2211 

1,00 1 384 1 

0,196109 

229 

4119 

1,0026973 

0,279474 

28g 

6660 

1, 0042302 

0,373863 

0,170 

0,0002238 

i,ooi4oio 

0,196441 

o,23o 

o,ooo4i56 

1,0036210 

0,280960 

0,390 

0,0006708 

1,0042611 

0,375521 

171 

2265 

i,ooi4i8i 

0,197775 

33l 

4iq4 

1 ,0026448 

0,282450 

291 

6766 

1,0043933 

0,377191 

172 

2292 

1,0014353 

0,1991  13 

233 

423 1 

1,0026687 

0,283943 

392 

6804 

1,0043333 

0,378865 

173 

2319 

i,ooi4535 

o,3oo45i 

2  33 

4269 

1,0026928 

0,285437 

3g3 

6862 

1 ,0043547 

o,38o642 

174 

2347 

1,0014699 

0,201793 

234 

43o6 

1,0027169 

0,286935 

394 

6901 

1, 0043861 

0,382222 

0,175 

0,0002374 

1,0014873 

o,2o3i37 

0,235 

0,0004344 

1,0027412 

0,288435 

0,296 

0,0006960 

1,0044177 

o,383go6 

176 

2402 

I ,001 5o49 

o,2o4484 

2  36 

4382 

1 ,0027666 

0,289939 

296 

6999 

1 ,0044493 

o,3855g3 

177 

243o 

1,001 5226 

o,2o5833 

237 

4421 

1,0027901 

0,391446 

397 

7048 

1 ,00448 1 3 

0,387283 

178 

2458 

1. 001 5404 

0,207184 

238 

445g 

1,0028148 

0,292964 

298 

7097 

i,oo45i3i 

0,388977 

7  79 

2486 

1, 001 5583 

o,3o8538 

239 

4498 

i,oo283q5 

0,294466 

'99 

7147 

1,0045462 

0,390673 

0,180 

0,00025 1 5 

1,001 5-64 

0,209894 

0,240 

0,000453- 

1,0038644 

0,395980 

o,3oo 

0,0007196 

1 .0046774 

o.3q9374 

TABLE    VI.  —For  an  Hyperbola. 

This  table  is  used  in  finding  the  true  anomaly  v  of  a  comet,  moving  in  a  hyperbolic  orbit,  which  approaches  very  nearly  to 
the  form  nf  a  parabola;  the  excentricity  e,  the  perihelion  distance  D,  and  the  lime  t  from  passing  the  -perihelion  being 
given.  Like  the  preceding  table,  it  is  not  restricted  to  the  first  and  second  powers  of  e  —  1,  but  includes  nil  the  powers  of  that 
quantity. 

Rule.     From  e  find  0.-'2  =  0,1 -j-0,9  .  e;  and  then  the  approximate  value  of  log. /'  from  the  formula, 

Approx.  log.  ('  =  log.  t-\-\cg.  a'  —  f^'og-  D. 
With  this  value  of  (',  find  the  corresponding  value  of  U,  in  Table  IIL,  also, 

log.  /3  =  log.  (e  — l)+arith.  co.  log.  a'2  + 9,6989700  — 10,0000000; 

Approx.  log.  .4  =  log.  ^-\-2  log.  tang.J  U. 

Enter  Table  VL,  with  the  natural  number,  corresponding  to  this  value  of  log.  A,  and  find  in  it  the  corresponding  log.  B  ;  which 

is  to  be  subtracted  from  the  approximate  log.  (',  to  obtain  the  corrected  value  of  log.  ('.     With  this  corrected  value,  find  in  Table 

IIL,  the  corrected  value  of  log.  U;  and  for  distinction,  we  shall  call  it  w;  then   the    corrected  value  of  log.  A  is  found  by  the 

following  formula,  which  is  similar  to  the  preceding; 

Correct,  log.  A  =  log.  /2  -|-  2  log.  tang.^  w. 
It  will  very  rarely  be  necessary  to  repeat  the  operation,  to  get  a  more  accurate  value  of  A  ;  we  shall  therefore  use  it,  in 
finding  the  correct  value  of  C,  in  Table  VI.,  and  then, 

A  «4-1   _ 

1  ' 


tang.2  i  t! 


C-|-0,8.^  ■  e- 
C-\-a,S.A 


[Anomaly  v\. 


.  D.sec.Si  V. 


[Radius  vector  r]. 


C  —  0,2.A 

In  computing  a  large  number  of  observations,  it  will  frequently  happen  that  the  value  of  B  is  very  nearly  known,  at  the 
commencement  of  the  operation;  in  this  case,  the  correction  B,  may  be  applied  in  the  first  process,  for  finding  the  approximate 
value  of  t'. 


Given  the  excentricity  e=  1,261882;  log.  perihelion  distance 
Approximate  Operation. 
a'2  =  0,1 +0,9.  e^  1,2356938  log. 

a'  log. 

D  log.  CO. 

its  half 
log. 

Approx.  log.  f 


EXAMPLE. 

0,0201667;  t  =  65''''^',4i236  ;  to  find  e  and  r. 


t  =  65^'')",4i236 


Hence  ^7=  70" 32"",  nearly,  in  Table  III. 
e  — 1=0,261882  log. 

a'2  log.  CO. 

Constant  log. 

Sum  gives  y3  log. 
à  £7=35'' 1 6""  tang. 

same 

Approx.  .4  =  0,05299  log. 

Corresponding  log.  B  =  0,0000207,  Table  VI. 


0,0919108 

0,0459554 
9,9798343 
9,9899171 
1,8 1 56598 

1, 83 1 3666 


9,4i8io56 
9,9080892 
9,6989700 


9,0251648 

9,84952 

9,84962 


8,72420 


Corrected  Operation. 


Subtract  log.  5  =  0,0000207  gives  correct  log.  t'=  i, 83 1 3469 
Hence  î/ort/)^70  3i    87^,0  in  Table  III. 


è«)  =  35S5'"48',5 

Corrected  A  =  0,0629792 

0,8  A  =  0,0423834 
C  =  1,0001261 


same 
tang, 
same 

log. 


C  -|-  0.8  -^  =  1,0426095 
e  -j-  I  =  2,261882 
e  —  I  ^  0,261882 


Sum  is  2  log.  tang.  J  v 


u  =  33  3i     3o 

f.    d       .,771  S 

V  =  67  o3    00 
C  —  0,2  ./Î  =  0,9895303 
C4-0)8-^=  1.0426096 
D 

4  0  =  33  3 1  3o 


tang. 


9,0261648 
9,8494702 
9,8494702 

8,7241062 


log.  CO. 

9,9819200 

log. 

0,3544699 

log.  CO. 

0,6818944 

9,6423896 

9,8211947 


g.  CO. 

0,0046709 

log- 

0,0180800 

log. 

0,0201667 

sec. 

0,0790189 

same 

0,0790189 

log. 

0,2008544 

TABLE    VI.  —For  an  Hyperbola. 

/»  the  inverse  problem,  we  have  given,  the  true  anomali/  v,  the  perihelion  distance  D,  and  the  excentricily  e,  to  find  the  lime 
tfrom  the  perihelion  in  days.     This  is  obtained  by  the  following  rule,  which  is  similar  to  that  for  an  ellipsis,  in  the  last  table. 

Ç     \ 

Rule.    With  e  and  »  find  T  =  — —  .  tang.-'  4  p,  and  then  by  Table  VI.,  the  corresponding  value  of  C.     Also, 

Log.  A  =  log.  T  +  log.  C  -f  arilh.  co.  log.  (1  —  0,8  .  T)  ; 
and  the  corresponding  log.  B,   in  Table  VL     Then  find, 

log.  t^  =  2,0654486  -j- 1  log.  D  +  i\og.A  +  log.  B  —  A  log.  (e  —  1  )  ; 
log.  «2  =  log.  <i  +  8,8239087  +  log.  A  +  log.  (1  _(-  9 e)  —  log.  (e  —  1)  ; 


EXAMPLE. 
Given  a-s  before  £=1,261882;  log.  perihelion  distance  i)=  0.0201657  ;  and  the   true  anomaly  t!  =  67'' o3"o' ;    to  find   th 
time  from  the  perihelion  (. 

e — i=a=o,26i882  log.  9,4i8io56 


e-|-i         =2,261 
è»=33"'3i"'3o' 


82    log.  CO.  9,6455301 

tang.  9,8aiig46 

same  tang.  9,8211946 


T  =  0,0508189  log.  8,7060249 

Hence  C^  1,0001261  Table  VL  log.  o,oooo548 
1  —  0,8  T  =:  0,9593449  log.  CO.  0,0180232 

.4=:  0,0529791  log.   8,7241049 


Corresponding  log.  B  in  Table  VI.  0,0000207 


f  J  =  56'^°ySo683o 


f„=  g*"'^',  34407 


Itj-f  (,=65''^y%  41237  =  f. 

TABLE    VI. 


Constant  log.  2,o654486 

§  log.  D  o,o3o2485 

è  log.  A  9,362o5s4 

log.  B  0,0000207 

•  àIog-(«  —  l)arith.co.  0,3909472 

log.  1,7487174 

Constant  8,8239087 

A   log.  8,7241049 

I -|-9  e=  I2,356g38  log.  1,0919108 

(e  —  i)  log.  CO.  0,5818944 

log.  0,9705362 


A 

Log.  B 

c 

T 

0,00000 

A 

Log.  B 

c 

T 

A 

Log.  B 

c 

T 

0,000 

0,0000000 

1 ,0000000 

o,o4o 

0,000011 8 

1,0000722 

0,038757 

0,080 

0,0000468 

1, 0002850 

0,075168 

001 

000 

1 ,0000000 

0,00100 

o4i 

124 

1,0000758 

o,o3g6g5 

081 

480 

1,0002921 

0,076050 

002 

000 

1,0000002 

0,00200 

042 

i3o 

1, 000075g 

o,o4o632 

082 

492 

I  ,ooo3gg2 

0,076930 

oo3 

001 

1 ,0000004 

0,00299 

043 

1 36 

1 ,0000833 

o,o4i567 

o83 

5o4 

1  ,ooo3o65 

0,077810 

004 

001 

1 ,0000007 

0,00399 

044 

143 

1,0000872 

o,o425oo 

084 

5 16 

I  ,ooo3 1 38 

0,078688 

o,oo5 

0,0000002 

1,0000011 

o,oo4g8 

0,045 

0,0000149 

1,0000912 

0,043432 

o,o85 

0,0000528 

I,00032I2 

0,079564 

006 

oo3 

1,0000016 

0,00597 

o46 

i56 

1,0000953 

o,o44363 

086 

540 

1 ,0003287 

0,080439 

007 

oo4 

1,0000022 

0,00696 

047 

i63 

1 ,0000994 

o,o452g2 

087 

553 

1, 0003363 

o,o8i3i3 

008 

oo5 

1 ,0000029 

o,oo7g5 

048 

170 

1, 0001037 

0,046220 

088 

566 

1  ,ooo344o 

0,082186 

009 

006 

1 ,0000037 

o,oo8g4 

049 

177 

1,0001080 

0,047147 

089 

578 

i,ooo35i7 

o,o83o57 

0,010 

0,0000007 

1 ,0000046 

0,00992 

o,o5o 

0,0000184 

1,0001124 

0,048072 

0,090 

o,oooo5gi 

1,0003595 

0,083927 

on 

009 

1, 0000055 

0,01090 

o5i 

19' 

1,0001  i6g 

o,o489g5 

ogi 

6o4 

1 ,0003674 

0,084796 

012 

on 

1 ,0000066 

0,01 i8g 

o52 

199 

l,00012l5 

O,o4ggi7 

092 

618 

1,0003754 

o,o85663 

oi3 

oi3 

1 ,0000077 

0,01287 

o53 

207 

1,0001262 

o,o5o838 

og3 

63 1 

i,ooo3835 

o,o8652g 

oi4 

oi5 

1 ,000008g 

0,01 384 

o54 

2l5 

i,oooi3io 

o,o5i757 

094 

645 

1,0003917 

o,o873g4 

0,0 1 5 

0,00000:7 

1,0000102 

0,01482 

o,o55 

0,0000223 

1, 0001 338 

0,052675 

0,095 

o,oooo658 

1,0003999 

0,088257 

016 

0T9 

1,0000116 

o,oi58o 

o56 

23  I 

1,0001407 

o,o535g2 

096 

673 

i,ooo4o83 

0,089119 

017 

021 

1,00001 3 1 

0,01677 

o57 

23g 

1,0001 4  58 

o,o545o7 

097 

686 

1,0004167 

0,089980 

018 

024 

1,0000147 

0,01774 

o58 

247 

i,oooi5og 

o,o5542o 

098 

700 

1,0004252 

O,ogo84o 

019 

027 

1,0000164 

0,01872 

o5g 

256 

i,oooi56i 

o,o56332 

099 

714 

1,0004338 

0,091698 

0,020 

o,ooooo3o 

1,0000182 

0,01 g68 

0,060 

0,0000265 

1,0001614 

0,057243 

0,100 

0,0000728 

1 ,0004424 

0,092555 

021 

o33 

1 ,0000200 

0,02065 

061 

273 

1,0001667 

o,o58i52 

101 

743 

1,00045 12 

0,093410 

022 

o36 

1,0000220 

0,02162 

062 

282 

1,0001722 

o,o5go6o 

102 

758 

1 ,0004600 

0,094265 

023 

039 

1 ,0000240 

0,02258 

o63 

2gi 

1,0001777 

0,059967 

io3 

772 

1 ,0004689 

o,og5ii8 

024 

043 

1 ,0000261 

0,02355 

064 

3oi 

i,oooi833 

0,060872 

104 

787 

1,0004779 

0,o95g6g 

0,025 

o,ooooo46 

1,0000283 

0,0245 1 

o,o65 

o,oooo3io 

I, 000 I 8g I 

0,061776 

o,io5 

0,0000802 

1,0004820 

0,096820 

026 

o5o 

1  ,oooo3o6 

0,02547 

066 

320 

i,ooorg4g 

0,062678 

106 

8.7 

1 ,0004962 

0,09766g 

027 

o54 

1  ,oooo33o 

0,02643 

067 

329 

1,0002007 

0,063579 

107 

833 

i,ooo5o54 

o,og85i7 

028 

o58 

i,oooo355 

0,02739 

068 

33g 

1,0002067 

0,064479 

108 

848 

i,ooo5i48 

0,099364 

029 

062 

i,oooo38i 

0,02834 

069 

349 

1,0002128 

0,065377 

109 

864 

1,0005242 

0,100209 

o,o3o 

0,0000067 

1 ,0000407 

0,02930 

0,070 

0,0000359 

1,0002189 

0,066274 

0,110 

0,0000880 

1 ,0005337 

o,ioio53 

o3i 

071 

1,0000435 

o,o3o25 

071 

370 

1, 000225] 

0,067170 

11 1 

895 

i,ooo5432 

o,ioi8g6 

o32 

076 

1  ,oooo463 

o,o3 1 20 

072 

382 

1,00023 1 4 

0,068064 

112 

911 

1,0005539 

0,102738 

o33 

080 

1 ,0000492 

o,o32i5 

073 

390 

1,0003378 

o,o68g57 

ii3 

928 

1,000  5626 

0,103578 

o34 

o85 

i,oooo523 

o,o33io 

074 

401 

1,0003443 

o,o6g848 

114 

944 

1,0005724 

o,io44i7 

o,o35 

0,0000091 

1, 0000554 

o,o34o4 

0,075 

0,00004l2 

i,ooo25og 

0,070738 

o,ii5 

0,0000960 

i,ooo5823 

o,io5255 

o36 

096 

i,oooo585 

0, 03499 

076 

423 

1,0002575 

0,071627 

116 

0977 

i,ooo5g23 

0,106092 

o37 

lOI 

1,0000618 

o,o35g3 

077 

434 

1 ,0003643 

0,072514 

117 

0994 

1 ,0006034 

0,106927 

o38 

107 

1, 0000652 

o,o3688 

078 

445 

1,0002711 

0.073400 

118 

1010 

1,0006135 

0,107761 

039 

112 

1 ,0000686 

0,03782 

079 

457 

1,0002780 

0,074285 

119 

1027 

1,0006328 

o,io85g4 

o,o4o 

0,0000118 

1.0000722 

0,03876 

0,080 

0,0000468 

1,0002850 

0.075168 

0,120 

0,0001045 

1. 00063 3 1 

o,iog426 

a24 


TABLE  VI.  — For  an  Hyperbola. 

To  find  the  true  anomaly  in  a  hyperbolic  orbit,  which  is  nearly  of  a  parabolic  form,  by  the  method  of  Gauss. 


Log.  B 


0,120 
121 

123 
123 
124 

0,125 

126 

127 

128 
129 

0,1 3o 
i3i 

l32 

i33 
1 34 

o,i35 

1 36 

1 37 
i38 
1 39 

0,1 4o 
i4i 
i4a 
i43 
144 

0,145 
i46 
147 
I 
1 49 

o,i5o 
i5i 
iSa 
i53 
1 54 

o,i55 
1 56 
l57 
1 58 
159 

0,160 
161 
163 
1 63 
164 

0,1 65 

166 
1 6 
168 
169 

0,170 

171 
172 
173 
174 

0,175 

176 
177 
178 

179 
0,180 


0,0001045 
1062 
1079 
1097 
iii4 

0,0001 133 
ii5o 
1 168 
1 186 

I2o5 
0,0001223 

1242 
I26I 

1280 
1299 

0,0001 3 18 
i337 
i357 
1376 
1396 

o,oooi4i6 
1 436 
i456 
1476 
1497 

o,oooi5i7 
1 538 
1 559 
i58o 
1601 

0,0001623 
1643 
i665 
1686 
1708 

0,0001730 
1752 
1774 
1797 
1819 

0,0001843 
1864 
1887 
1910 
1933 

0,0001956 
1980 
2oo3 
2027 

205l 

0,0002075 

2099 

2133 
2l47 

2172 
0,0002196 

2221 
2246 
2271 
2296 
0,0003321 


1, 000633  I 
1,0006435 
1 ,0006539 
1,0006645 
1,0006751 

I  ,ooo6858 
1 ,0006966 
1,0007075 
1,0007185 
1,0007295 

1 ,0007406 
1 ,00075 1 8 
1 ,000763 1 
1 ,0007745 
1,0007859 

1 ,0007974 
1 ,0008090 
1,0008207 
1,0008325 
1 ,0008443 


0,109426 
o,iio356 
o,iiio85 
0,111913 
0,112740 

o,ii3566 
0,114390 
o,ii52i3 
o,ii6o35 
o,ii6855 

0,117675 
0,118493 
0,119310 
0,120126 
0,130940 

0,121754 
o, 122566 
0,123377 
o,i24r86 
0,124995 


,0008562  0,1 25802 
1,0008682  0,126609 


I  ,ooo88o3 
1,0008935 
1 ,0009047 

1,0009170 
1 ,0009294 
1 ,00094 1 9 
1 ,0009545 
1,0009671 

1,0009798 
1,0009926 
i,ooioo55 
i,ooioi85 
i,ooio3i5 


1,0010578 
1,001071 1 
1,0010844 
1,0010978 

1,001 1 1 13 
1,0011349 
1,001 1 386 
1,001 1 523 
1,0011661 

1,0011800 
1,0011940 
1,0012081 
1,0012222 
1,0012364 

1,0012507 
1, 00 1 265 1 
1,0012795 
1,0013940 
i,ooi3o86 

i,ooi3333 
i,ooi338o 
1,0013539 
1,0013678 
1, 001 3827 
1,0013978 


o,i274i4 
0,128217 
0,139020 

0,129822 
o,r3o622 
o,i3i42i 
0,132219 
o,i33oi6 

0,i338t2 
0,1 34606 
0,1 3  5399 
0,136191 
0,13698a 


i,ooio446  0,137772 


o,i3856i 
o,i3g349 
o,i4oi35 
0,140920 

o,r4i7o4 
0,142487 
0,143269 
o,i44o5ù 
0,144829 

o,i456o8 
o,i46385 
0,147161 
0,147937 
0,148710 

o,i49483 
o,i5o255 
o,i5io26 
o,i5i795 
o,i52564 

o,i5333i 
0,154097 
0,154862 
0,155626 
0,1 56389 
0,i57i5i 


Log.  B 


0,180 
181 
182 

1 83 
184 

o,i85 
186 

187 

189 

0,190 

191 
192 
193 
194 

0,195 
1 96 

197 
198 

199 

0,200 
201 
202 
2o3 

204 

o,2o5 
206 

207 

208 
209 

0,210 
211 
212 
2l3 
2l4 

0,2  I  5 

216 

217 

3l8 
219 

0,220 
331 
222 
223 
224 

0,225 
226 
227 
228 
229 

o,23o 

23l 
232 

233 
234 


0,235 
236 
287 
238 
239 

0,340 


0,0002321 

2346 
2872 

2398 

2423 

0,0002449 
2475 

25o2 

2528 
2554 

o,ooo258i 
2608 
2634 

2661 

2688 

0,0002716 

2743 
2771 
2798 

2826 
0,0002854 

2882 

2910 

2938 

2967 

0,0003995 
3o24 
3o53 
3082 
3iii 

o,ooo3i4o 
3169 

3199 
3228 
3258 

0,0003288 
33i8 
3348 
3378 
3409 

0,0003439 
3470 
35oo 
353 
3562 

0,000359. 
362  5 
3656 
3688 
3719 

0,000875 1 
3783 
38i5 
3847 
388o 


0,0008912 
8945 

3977 

4oio 

4o43 

0,0004076 


1,0018978 
1,0014129 
1,0014281 
1,0014434 
i,ooi4588 

1,0014742 
1,00 

i,ooi5o54 
1, 001 52 10 
1, 001 5368 

1,0015526 
1,001 5685 
I, 001 5845 
i,ooi6oo5 
1,0016167 

1,0016829 
1,0016491 
1,0016655 
1,0016819 
1,0016984 

i,ooi7i5o 
1,0017817 
1,0017484 
1,0017652 
1,0017821 

1,0017991 
1,0018161 
i,ooiS333 
i,ooi85o4 
1,0018677 

i,ooi885o 
1,0019024 
1,0019199 
1,00x9875 
1,1019551 

1,0019728 
1,0019906 
1 ,0020084 
1 ,0020264 
1 ,0020444 

1,0020625 
1,0020806 
1 ,0020988 
1,00211 
1, 002 1 355 

1 ,002 1 540 
1,0021725 
1,0021911 
1,0022098 
1,0022285 

1,0022478 
1,0022662 
1, 002 285a 
1,0028043 
1,0028284 


1,0023425 
1,0028618 
1,0028811 
I  ,oo24oo5 
1,0024200 
1,0034396 


o,i57i5i 
0,157911 
0,158671 
0,159439 
0,160187 

0,160948 
0,161698 
0,162453 
0,168206 
0,163958 

0,164709 
o, 165458 
0,166207 
0,166955 
0,167702 

0,168447 
0,169192 
o,i6gg35 
0,170678 
0,171419 

0,172159 
0,173899 
0,178637 
0,174374 
0,175110 

0,175845 
0,176579 
0,177813 
0,178044 
0,178775 

o,  179505 
0,180334 
0,180962 
0,181688 
0,182414 

0,188189 
o, 188863 
o,i84585 
o,t858o7 
0,186028 

0,186747 
0,187466 
0,188184 
0,188900 
0,189616 

o, 190881 
o,igio44 
0,191757 
0,192468 
0,198179 

0,198889 
0,194597 
o,  ig53o5 
o,jg6oi2 
0,196717 


0,197433 
0,198136 
0,198839 
o,igg53o 
0,200281 
0,200981 


Loff.  B 


0,240 
241 
242 
248 
244 

0,245 
246 

247 
248 

249 

o,25o 

25l 
252 

253 

254 

0,255 
2  56 
257 
258 
259 

0,260 
261 
262 
268 
264 

0,265 
266 
267 
268 
269 

0,270 
271 
272 
278 
274 

0,275 
276 
277 
278 
279 

0,280 
281 
282 
288 
284 

0,285 
286 
387 
288 
289 

0,390 
291 
292 
298 
294 


0,0004076 
4iio 
4i43 
4176 
42 

0,0004244 

4277 
43ii 
4846 
438o 

o,ooo44i4 


4483 
45i8 
4553 

0,0004588 
4628 
4658 
4644 
472g 

0.0004765 
4801 
4838 
4878 


o,ooo4g45 
4g8i 
5oi8 
5o55 
5ogi 

o,ooo5 128 
5i65 
5302 
5340 

5277 

o,ooo53i5 
5352 
5390 
5428 
5466 

o,ooo55o4 
5542 
558 1 
56iQ 
5658 

0,0005697 
5786 
5775 
58i4 
5853 

0,0005898 
5982 
5972 
6012 
6o52 


1,0034896 
1, 0024593 
1,002478g 
1,0034987 
i,oo25i85 

1,0025334 
1,0025584 
1,0025785 
1,0025986 
1,00261" 

1,0026891 
1,0036594 
1 ,0036799 
1,0027004 
1,0027209 

100,27416 
1,0027628 
1,0027880 
1,0028089 
1,0028248 

1,0028458 

1,0028669 

1,00288" 

1,0029093 

1,0029305 

1,0029519 
1 ,0029733 
1,0029948 
1, 0080164 
1 ,0080880 


I  ,oo3o8 1 5 
I,oo3io38 
1,0081253 
1,0081478 


0,200981 
0,201680 
0,202828 
0,308025 
0,208721 

o,2o44i6 

0,205lI0 

o,2o58o3 
0,206495 
0,207186 

0,207876 
o, 208565 
0,209254 
0,209941 
0,210627 

0,21  i3i8 
0,211997 
0,213681 
0,2 1 3864 
n,2i4o45 

0,214736 
0,21 5406 
o,3i6o85 
0,216768 
0,217440 

0,218116 

0,218791 
0,219465 

0,220l38 

0,220811 


1,0080597  0,221482 


0,295  0,0006093 


396 
297 
298 

=99 
o,3oo 


6182 
6172 
6218 
63  53 
0.0006394 


i,oo3igi5 
1,0082187 
1,0082859 
1,0082583 

1 ,0082807 
1,0088082 
1, 0088257 
1 ,0083484 
1,0088711 

I  ,oo33g38 
1,0084167 
I  ;oo84396 
1,0084626 
1, 00848 56 

1, 0035087 
1, 0085819 
i,oo35552 
1,0035785 
1,0086019 

I, 0086253 
I ,0086489 
1,0086725 
1,008696! 
1,0087199 
1,003^437 


0,223l58 
0,222822 

o,2234gi 
o, 224159 


1,0031693  0,224826 


0,335492 
0,226157 
0,226821 
0,227484 

9,228147 
0,228808 
0,239469 
0,280128 
0,280787 

0,281445 
0,282102 
0,282758 
0,283418 
0,234068 

0,234721 
0,285874 
0,286025 
0,286676 
0,287826 

0,287975 

0,288628 
0,289371 
0,389917 
o,24o563 
0,241207 


TABLE   VII. —For  a  Parabola. 

This  table  is  for  co7nputing  Ihe  time  t  in  days,  for  a  cornel  to  describe,  in  a  parabolic  orbit,  an  arc  of 
the  true  anomaly,  re2irese7ited  by  v'  —  v  =  2f.  This  arc  2  f  being  given,  together  with  the  extreme 
radii  r,  r'. 

Rule.  Put  tang,  z  =  i/-  ;  cos.  y  =  cos.  /.  sin.  2  z. 

With  this  value  of  y,  find  in  Table  VII.  the  corresponding  log.  C;  then  we  have, 

log.  t  =  Iog.  C-(-log.  sin.èy  +  S.log.  (^). 


EXAMPLE. 

Given  log.  >•  =  9,9ii5i4o.  log.  7^=  9,7902520  ;  2/=i  11  44'"  22'  ;  to  find  (  in  days. 
4  log.  r"  9,8951260 


è  log-  r   9,9557670 


=  4i° 


22  =  82" 


1  o  s 
37 

f=   5  52  n 
y=  9  53  22 


8'  ,5  tang.  9,9393690 

■  ''"     sin.  9,9957814 

COS.  9,9977170 


cos.  9,9934984 


è  log.  r  9,955757c 
z   COS.  9,8776911 

^^^    log.  0,0780659 

Multiplied  by  3  .  log.  0,2341977 
Table  VII.  log.  C.  1,7622613 

è  2/  =  4"*  56"" 4i'    sin.  8,9354800 
ï=8    ",54g4    log.  0,9319390 


With  the  two  radii  r, 
to  describe  that  arc,  in 


TABLE    VII.  —  For  a  Parabola. 

r,  )■',  and  the   included  arc  »'  —  v=  if,  to  find  the  time  t  in  days,  for  a  comet 
parabolic  orbit. 


d  m 
0,00 
0,10 
0,20 
o,3o 
o,4o 
o,5o 

1,00 
1,10 
1,20 
i,3o 
Mo 
T,5o 

2,00 
■2,10 
2,20 
2,3o 
2,40 
2,5o 

3,00 

3, 

3,20 

3,3o 

3,40 

3,5o 

4,00 
4,10 
4,20 
4,3o 
4,4o 
4,5o 
5,00 


1,7644177 
1,7644171 
1,7644153 
1,7644122 
1 ,7644079 
1,7644024 

1,7643957 
1,7643877 
1,7643785 
1,7643681 
1,7643565 
1,7643436 

1,7643395 
1,7643142 
1,7642977 
1,7642799 
1,7642610 
1,7642408 

1,7642193 
1,764196' 
1,7641728 
1,7641477 
1,7641213 
1 ,7640938 

1, 7640650 
1, 76403 5o 
1,7640037 
1,7639713 
1 ,7639376 
1 ,7639027 
1,7638665 


6 
18 
3i 
43 
55 

67 

80 

92 

io4 

116 

129 

i4i 

i53 
i65 
178 
189 
202 

2X5 

226 
239 

25l 

264 
275 

288 

3oo 
3i3 
324 
337 

349 
362 

373 


Log.  C 


d  111 
5,00 

5,10 

5,20 

5,3o 
5,40 
5,5o 

6,00 
6,10 
6,20 
6,3o 
6,4o 
6,5o 

7,00 
7,10 
7,20 
7,3o 
7^0 
7,5o 

8,00 
8,10 
8,20 
8,3o 
8,4o 
8,5o 

9,00 

9;I0 
9.20 

9,3o 

9,40 

9,5o 

10,00 


1,7638665 
1,7638292 
1 ,7637906 
1 ,7637508 
1,7637097 
1 ,7636675 

1 ,7636240 
1,7635793 
1,7635334 
1,7634862 
1 ,7634378 
1,7633882 

1 ,7633374 
1,7632853 
1,7632320 
1,7631775 
1,7631217 
i,763o648 

1 ,7630066 
1,7629471 
1,7628865 
1,7628247 
1,7627616 
1,7626973 

1,7626318 
1,7625550 
1,7624970 
1,7624278 
1,7623574 
1,7622858 
1,7622129 


373 
386 
398 
411 
422 

435 

447 
459 
472 
484 
496 
5o8 

521 
533 
545 
558 
569 

582 

595 
606 
618 
63 1 
643 

655 

668 
680 
692 
704 
716 

729 

-4 1 


d  m 
10,00 
10,10 
10,20 
IO,3o 
10,; 
10, 5ù 

11,00 
11,10 
11,20 
II, 3o 
II, 40 
11, 5o 

12,00 
12,10 
12,20 
12, 3o 
i2,4o 

12,5o 

1 3,00 
i3,io 

l3,20 

i3,3o 
i3,4o 
i3,5o 

1 4,00 
i4,io 
i4,2o 
i4,3o 
1 4,40 
i4,5o 
1 5,00 


liOg.  C 


1,7622129 

1,762138s 

1 ,7620634 
1,7619869 
1,7619091 
1,7618301 

1,7617498 
1,7616684 
1,7616857 

1,7616017 

1,7614166 

i,76i33o3 

1,7612427 
1,7611539 
1,7610638 
1 ,7609726 
1 ,760880 1 
1 ,7607864 

1,7606916 
1,7606963 
1 ,7604980 
1 ,7603994 
1,7602996 
1,7601986 

1 ,7600962 
1.7599927 
1,7598880 
1,7697820 
1,76967  ' 
1 ,7696664 
1,7694568 


Diff. 


neg. 

74 1 
754 
766 
778 
790 
So3 

814 
827 
84o 
861 
863 

876 


901 
gi2 
926 
937 

062 

973 
986 

999 

lOIO 

1023 

io35 
io47 
1060 
1073 
1084 
1096 
1109I 


16,00 
i5,io 
1 5,20 
i5,3o 
16,40 
i5,5o 

16,00 
i6,io 
16,20 
16, 3o 
i6,4o 
16,60 


1,7594568 
1,7693469 
1,7692338 
1,7691206 
1,7690060 
1,7688903 

1,7687733 
1,758655 1 
1,7685357 
i,7584i5o 
1,7682931 
1,7681700 


17,00  1,7680457 
17,10  1,7679201 


17,20 
i7,3o 
17,40 
17,60 

18,00 
18,10 
18,20 
i8,3o 
18,40 
i8,5o 

19,00 
19,10 
19,20 
19,30 
19,40 
19,60 
20,00 


1,7577933 
1,7676663 
1,7676361 
1,7674067 

1,7672740 
1,7671411 
1 ,7670070 
1,7668716 
1,7567361 
1,7665973 

1,7564583 
1,7663 1 80 
1,7661766 
1, 7660338 
1,7668899 
1,7557448 
1,7555984 


neg. 

1 1 09 
II2I 
Ii33 
1 145 
1167 

1 170 

1182 
1 194 
1207 
1219 

123l 

1243 

1266 

1268 

1280 

1292 
i3o4 

I3I7 
1329 
i34i 
i364 
i366 
1378 

1 390 

i4o3 
i4i5 
1427 
1439 
i45i 
i464| 


USES   OF   TABLES  VIII.   IX.    AND  X. 

Table  VIII.  combined  with  Table  IX.,  for  an  elliptical  orbit,  anJ  witli  Table  X.,  for  a  hyperbolic  orbit,  are  used  in  findin»;  the 
elements  of  the  orbit;  when  we  have  given,  the  two  radii  r,  )-',  the  included  heliocentric  arc  «'  — ti=2/,  and  the  time  t  of  describing 
that  arc,  expressed  in  days.  These  tables  are  limited  to  the  most  useful  values  of  h,  H,  which  do  not  exceed  0,6  ;  and  to  values  of  x,  z, 
which  do  not  exceed  0,3.  These  limits  include  the  most  common  cases  ;  and  in  observations  which  do  not  fall  within  them,  we  can  use 
the  indirect  solutions  explained  in  this  appendix.  VVkeii  h  or  H  exceeds  0,040,  and  log.  yy,  or  log.  YV,  is  required  to  be  correct  in 
the  seventh  decimal  place,  ice  must  use  the  second  differences. 


PRECEPTS  FOR  TABLES  VIII.,  IX.,  IN  AN  ELLIPTICAL  ORBIT. 

The  particular  object  of  these  tables  is  to  facilitate  the  computation  of  the  value  of  O  §:  =  £'  —  E,  representing  the  diflference  between 
the  two  excentric  anomalies  E',  E;  corresponding  respectively  to  the  true  anomalies  v',v;  which  is  an  important  part  of  the 
preliminary  process,  in  computing  the  elements  of  the  orbit.  After  g  has  been  found,  the  elements  may  be  computed  by  the  methods, 
given  in  this  appendix  ;  we  shall  not  however  enter  here  upon  this  subject,  but  shall  restrict  our  remarks  to  the  mere  explanation  of  the 
method  of  computing  the  value  of  g,  by  means  of  the  tables. 

Iq  the  calculation  of  g,  there  are  two  separate  cases  ;  the  one  when  /  is  acute,  or  t)'  —  ti  between  0    and  180   ;  the  other  when  J  is 

obtuse  or  v' v  between  ISO''  and  360''.     We  shall  give  the  precepts,  in  both  the.^e  cases,  at  full  length,  for  convenience  of  reference  ; 

remarking,  however,  that  the  case  of/  being  acute,  is  that  which  occurs  most  frequently  in  practice,  and  is  that  for  which  these  tables 
are  particularly  designed. 


When  f  is  acute. 
We  must  find  w,  I,  mm,  h,  by  the  following  formulas  ; 

tang.  (45  +ii>)=\/  -; 


1  = 


sin. 2  hf     tang.a  2  u) 


cos.  /      '  COS.  / 

log.  mm  =  5,5680729  +  2  log.  t  —  3  log.  cos./—  f  log.  {rr')  ; 

Approx.  log.  7»  =  log.  mm  —  log.  (7  -f  f  )  • 
With   this  approximate   value  of  h,   find,  in   Table  VIII.,  the 


coresponding  approximate  value  of  loi 

Approx.  value  oi  x^ 


yy,  also, 
mm 


men  f  is  obtuse. 
We  must  find  w,  L,  MM,  H,  by  the  following  formulas  ; 

tang.  (45'' -|-  w)=y/-; 
r 

sin.2  4/     tang.2  2  w 


L  = 


yy 


—  I. 


With  this  approximate  value  of  x,  find,  in  Table,  IX.,  the 
corresponding  approximate  value  of  *,  and  then  the  corrected 
value  of  ft,  from  the  formula, 

corrected  log.  7t  =  log.  mm  —  log.  ('  +  |  +  H  • 

With  this  corrected  value  of  h,  find  a  new  value  of  log.  yy,  in 
Table  VIII.,  which  is  to  be  used  in  finding  a  corrected  value  of  a-, 
by  the  formula  used  above, 

corrected  value  of  r  = —  I . 

yy 

If  necessary,  we  may  repeat  the  operation  until  the  assumed  and 
computed  values  of  J  agree  ;  then  we  have, 

X  =  sin.3  4  g  =  sin.2  i  (£'  —  £)  ; 
from  which  we  easily  obtain  g  or  E' —  E. 


cos.  /  cos.  / 

log.  JIO/=  5,5680729-}- 2  log.  «  —  3 log.  (—cos./)  — J  log.  {rr')  ; 

Approx.  log.  H=  log.  MM —  log.  (L  —  ^)  . 

With  this  approximate  value  of  H,  find,  in  Table  VIII.,  the 
corresponding  approximate  value  of  log.  YY,  also, 

Approx.  value  01  x  =  L — —  . 

With  this  approximate  value  of  x,  find,  in  Table  IX.,  the 
corresponding  approximate  value  of  |,  and  the  corrected  value 
of  H,  from  the  formula, 


corrected  log.  H  =  log.  MM  - 


-log.  (z,-!-^ 


)• 


With  this  corrected  value  of  H,  find  a  new  value  of  log.  YY, 
in  Table  VIII.,  which  is  to  be  used  in  finding  a  corrected  value  of 
.r,  by  the  formula  used  above, 

corrected  value  of  a:  =  i — — -  . 

If  necessary,  we  may  repeat  the  operation  until  the  assumed  and 
computed  values  off  agree  ;  then  we  have, 

X  =  sin.2  4  g  =  sin.2  1  (£'  _  E)  ; 
from  which  we  easily  obtain  g  or  E'  —  E. 


EXAMPLE. 
Given  log.  r  =  o,33o764o;  log.  7^  =  0,3222239:    i' —  «)  =  2/ =  7'' 34"  53",  73  ;  (  =  21'''''",  93391  ;    to  find  ig  =  E'  —  E,  or  rather 
i=sin.a  ig. 


r'    log.  0,3222239 
r     log.  0,3307640 


—  =tang.4(45''4-«))  log.  9,9914599 


45''4-.u)  =  44''5i™33'    tang.  9,9978650 

ft"*  .,-.* 
ui  =  —   o    27 


0,3222239 
0,3307640 

sum  0,6529879 

half  0,3264940 


(rr')a  log.  0,9794819 
arith.  co.  9,02o5i8i 


/=  3''47™  26' ,865     COS.  arith.  co.  0,0009512 


è/=i''53"43',4325 

sin.2  4/ 

±i  =  0,0010963480 

COS./ 

sin. 
same 

log. 

8,5194986 
8,5194986 

7,0399484 

tang.2  2  to                    ,       . 
— 2 —  =  0,0000242205 

COS./ 

Z  =  o,ooii2o5685 
1  =  0,8333333 

2l«^   — 16™  54'      tang.  7,6916163^ 

same  7,6916163» 

/  COS.  arith.  co.  0,0009512 

'!^'i-ii^  =  0,0000242205    log.  5,384i838 

COS./ 

constant  log.  5,5680729 

J  =  2I''')'^9339I   log.  i,34iii6o 

same  i,34iii6o 

(arith.  co.  log.  cos.  /)  X  3      o,oo28536 

|.  log.  T  r"    arith.  CO.  9,o2o5i8i 

mm  log.  7,2736766 

Approx.    a;  =  0,000748018 

The  correction.  Table  IX.,  corresponding  to  this  value  of  x  is  insensible,  therefore,  we  may  assume  this  value  of  x  for  the  true  value 
of  3in.2  4  g  =  0,0007480186. 


7 -f  I  =  0,8344539        log.  9,9214023 
■mm  log.  7,2736766 

Approx.  A  ^  o,O0225o47      log.  7,3522743 

Corresponds  in  Table  VIII.,  to  approx.   log.  ^y  =  o,oo2i633 

mm  log.  7,2736766 


yy 


=  0,0018685871     log.  7,271 5i33 


I  =  0,001  i2o5685 


PRECEPTS  FOR  TABLES  VIII.  AND  X.,  IN  A  HYPERBOLIC  ORBIT. 

The  process  for  calculatin;;  the  elL'iiients  of  a  liyperbolic  oiliit,  by  means  of  r,r\  v'  —  r=2/an.l  t,  varies  but  very  Utile  from 
that  in  an  elliptical  orbit,  wliicli  we  have  just  explained.  Tlie  formulas  for  the  computation  of  «',  I,  m,  L,  M,  are  identically  the 
sanic.     The  formulas  for  h,  H,  are  the  same,  with  the   exception  of  using  ("  Table   X,  instead  of  ç  Table  IX  ;  moreover  x  is  changed 

into  z.     For  convenience  in  reference  we  shall  here  give  the  formulas,  for  the  hyperbola,  arranged  in   the  same   order  as  lor   the 

ellipsis, 


J  = 


IVhen  f  is  acute. 

4  r' 
tang.  (45<'-\-w)=  v/-  ; 

sin.2  if  j^  tang.2  2  to 


COS.  /  cos.  / 

log.  mm  ^  5,5680729  +  2  log.  /  —  3  log.  cos./ —  ^  log.   (rr'); 

approximate  log.  h  =  log.  mm  —  log.  (I  +  ^). 
With  this  approximate  value  of /i,  find   in   Table  VIII.   the  cor- 
respoodiog  approximate  value  of  log.  yy,  also 

approximate  value  of  z  =  i . 

yy 

With  this  approximate  value  of  ;,  find  in  Table  X.  the  corres- 
ponding value  of  ^,  and  then  the  corrected  value  of  h,  from  the 
formula, 

corrected  log.  /i  =  log.  7ii77i  —  log.  C  +  ^-t-f)- 

With  this  corrected  value  of  A,  find  a  new  value  of  log.  yy,  in 
Table  V'lII.,  which  is  to  be  used  in  finding  a  corrected  value  of  z, 
by  the  formula  used  above,  namely, 

corrected  value  01  z^l — ■ . 

yy 

If  necessary  we  may  repeat  the  operation,  until  the  assumed 
and  computed  value  of  ^  agree  ;  and  this  must  be  taken  for  the  true 
value  of  ^,  to  be  used  in  computing  the  elements  of  the  orbit,  by 
(he  formulas  given  in  this  appendix. 


When  f  is  obtuse. 
4  r' 


tang.  (45''- 


L  =  - 


sin.2  4/      tang.2  2  to 
cos.  f  cos.  / 

log.  MM  =  5,56807394-  2  log.  <  —  3  log.  (—  cos. /)  —  ^  log.  (r  r')  ; 

approximate  log.  //=  log.  .MJ\I  —  log.  {L  —  -|  ). 
With  this  approximate  value  of  //,  find  in  Table  VIII.  the  cor- 
responding approximate  value  of  log.  VY,  also 

approximate  value  of  z  =  —  L  . 

With  this  approximate  value  of  2,  find  in  Table  X.  the  corres- 
ponding value  of  ^,  and  then  the  corrected  value  of  H  from  the 
formula, 

corrected  log.  jH'=  log.  MM—  log.  (i—  |  —  ^). 

With  this  corrected  value  of  H,  find  a  new  value  of  log.   ¥¥, 

in  Table  VIII.,  which  is  to  be  used  in  finding  a  corrected  value  of 

z,  by  the  formula  given  above,  namely, 

,      ,        ,  MM 

corrected  value  of  z  =  —mr  —  L  . 
IF 

If  necessary  we  may  repeat  the  operation,  until  the  assumed  and 
computed  value  of  f  agree  ;  and  this  must  be  taken  for  the  true 
value  of  ^,  to  be  used  in  computing  the  elements  of  the  orbit,  by 
the  formulas  given  in  this  appendix. 


EXAMPLE. 


Given  log.  r  =  o,o333585;  log.  r' =  o,20o854i  ;  »'  — »  =  2/=48''  12"";  «  =  5i, '''')"  49788;  to  find  z. 


r'  log.  o,2oo854i 
r  log.  0,0333585 


0,1674956 


45''-|-ti•  =  47''45'"28^47  tang.  0,0418739 


u>=    2  45    28',  47 


2tc=   5'' 30""  56',  94   tang.  8,98483x8 

same  8,9848318 

/  arith.  co.  cos.  0,0396081 


tang.2  2  u) 


cos.  f 


mm  log.  8,7591571 


o,20o854i 
o,o333585 

sum  0,2342126 

half  0,1171063 

(rr')tlog.  o,35i3i89 
arith.  co.  9,6486811 


^0.010215784     log.  8,0092717 


constant  5,5680739 

^  =  51'^''^',  49788     log.   1,7117894 

same  1,7117894 

(arith.  co.  log.  cos.  /)  X  3     0,1188243 

^  log.  rr'    arith.  co.  9,6486811 


i25 


/=24    6™    cos.  arith.  co.  o,o3g6o8i 


è/=i2    3 


sin.  g,3i9658i 
same  9,3196581 


siD.2  if 

COS.  f 

tang.2  2  w 


^0,047744604    log.  8,6789243 


COS./ 


=  0,010215784 


I  =  0,057960388 
1  =  0,8333333 


'  +  1  =  018913937         log.  9,9500208 
mm    log.  8,7591671 

Approx.  ?s^  0,0644371     log.  8,8091363 

Corresponds  in  Table  VIII.  to  approx.  log.  i/y  =  o,o56o848 

mm     log.  8,7591571 

=  o,o5o47454    log.  8,7030723 

yy  

I  =  o,o57g6o39 

Approx.  2  =  0,00748585    =1 

Corresponding  to  this  in  Table  X.  is  ^=  o,ooooo32 
Hence,    Z -f-|^ -1-^  =  0,8912969      log.  9,9500224 
mm     log.  8,7591571 

corrected  A  =  o,o64436g     log.  8,8ogi347 

Corresponds  in  Table  VIII.  to  corrected  log.  yy=o,o56o846 

mm     log.  8,7591671 
mm 


yy 


^^o,o5o47456 
t  =  0,05796039 


log.  8,7030725 


Corrected  z  =  o,oo748583    which  agrees  with  the  assumed  value. 


TABLE  VIII.  —  For  an  Ellipsis  or  Hyperbola. 


This  table,  with  Tables  IX.,  X.,ave 
,r' ;  the  included  Iieliocentric   ai-c  v' 


AN 

for  computing  the 
— 1!  =  2/,  and  the 


elements  of  the  orbit,  when  there  are  given  the  two 
time  (  of  describing  that  arc,  expressed  in  days. 


radii 


h 
H 


Log.  yy 
Los.  YY 


0,0000 
0001 

0OO3 

ooo3 
ooo4 

o,ooo5 
0006 
0007 
0008 
0009 

0,0010 
001 1 

001  3 

ooi3 
0014 

0,00 1 5 
0016 
0017 
0018 

0019 

0,0020 
0021 
0022 
0023 
0024 

0,0025 
0026 
0037 
0028 
0029 

o,oo3o 
oo3i 
od32 
oo33 
oo34 

o,oo35 
oo36 
oo37 
oo38 
0039 

o,oo4o 
oo4i 
0043 
0043 
0044 

o,oo45 
0046 
0047 
oo48 
0049 

o,oo5o 
oo5i 
oo52 
oo53 
00  54 

o,oo55 
00  56 
0057 
oo58 
ooSg 

0,0060 


0,0000000 
0965 
igSo 
2894 
3858 

0,0004821 
5784 

M? 
7710 
8672 

0^0009634 
10595 
1 1 557 

I25l7 

13478 

o,ooi4438 
15398 
16357 
17316 
18275 

0,0019234 
20192 
2ii5o 
22107 
23o64 

0,002402 
24977 
25933 
26889 
27845 

0,0028800 
29755 
30709 
3i663 
32617 

0,0033570 
34523 
35476 
36428 
37381 

o,oo38333 
39284 
40235 
4ii86 
421 36 

o,oo43o86 
44o36 
44985 
45934 
46883 

0,0047832 
48780 
49728 
50675 
51622 

o,oo5256g 
535i5 
54462 
55407 
56353 

0,0057298 


965 
965 
964 
964 

963 

963 
963 
963 
962 

962 

961 
962 
960 
961 

960 
960 
9^9 
959 
9^9 

959 
958 
958 

957 
957 

9^7 
956 
956 
956 
956 

955 

955 
954 
954 
954 

953 

953 
953 
952 
953 

95 1 

952 
951 
951 
950 

950 
950 
949 

94y 

9^9 
9^9 
948 
9-18 
9^7 
947 

947 
946 
947 
945 
946 
945 
q45 


h 
H 


0,0060 
0061 
0063 
oo63 
0064 

o,oo65 
0066 
0067 
0068 
0069 

0,0070 
0071 
0073 
0073 
0074 

0,0075 
0076 
0077 
0078 
0079 

0,0080 
0081 
0082 
oo83 
0084 

o,oo85 
0086 
008 
0088 
0089 

0,0090 
0091 
0093 
0093 
0094 

o,oog5 
0096 
0097 
0098 
0099 

0,0100 

OIOI 

0102 
oio3 
oio4 

0,0  io5 
0106 
0107 
0108 
0109 

0,0110 
0111 
01 12 
oii3 
oii4 

0,0 1 1 5 
0116 
0117 
0118 
0119 

0,0120 


Log.  ijy 
Log.  YY 


0,0057298 
58243 
59187 
601 3 1 
61075 

0,0062019 
62962 
63905 
64847 
65790 

0,0066732 
67673 
68614 
69555 
70496 

0,0071436 
73376 
73316 
74255 
75194 

0,0076133 

77071 
78009 
78947 
79884 

0,0080821 
81758 
82694 
83630 
84566 

o,oo855o2 
86437 
87372 
883û6 
89240 

0,0090 1 74 
91 108 
92041 
92974 
93906 

0,0094839 
95770 
96703 
97633 
98564 

0.0099495 
100425 
ioi356 
102285 
io32i5 

0,0 1  o4 1 44 
io5o73 
1 0600 1 
106929 
107857 

0,0108785 
109712 
1 1 0639 
iii565 
112491 

o,oii34i7 


Diff. 


945 
944 
944 
944 


943 
943 
942 
943 
942 

941 
941 
941 
941 

940 

940 
940 
939 
939 

939 
938 
938 
938 
937 
937 

937 
936 
936 
936 

936 

935 
935 
934 
934 

934 

934 
933 
933 
932 

933 

932 
931 
931 

931 

930 
901 

9=9 
930 

929 

929 
928 
928 
938 

928 

957 
927 
936 
936 
926 
936 


A 
H 


0,0120 

0131 
0132 
0123 
0124 

0,0135 
0126 
0127 
0128 
0139 

0,0  i3o 
oi3i 

Ol32 

oi33 
oi34 

0,01 35 
oi36 
oi37 
01 38 
0139 

0,0  i4o 

oi4i 
0142 
0143 
0144 

o,oi45 
0146 
014? 
oi48 
0149 

0,01 5o 
oi5i 

0l52 

oi53 
01 54 

0,01 55 
01 56 
oi57 
oi58 
0159 

0,0160 
016 
0163 
oi63 
0164 

0,01 65 
0166 
0167 
0168 
0169 

0,0170 
0171 
0173 
0173 
0174 

0,0175 
0176 
0177 
0178 

0179 
0;Oi8o 


Log. 
Log. 


yy 

YY 


o,oii34i7 
114343 
1 1 5268 
116193 
117118 

0,0118043 
11896' 
119890 
120814 
121737 

0,0122660 
123582 
i245o5 
125427 
126348 

0,0127269 
128190 
129111 
i3oo32 
1 30952 

0,0131871 
132791 
133710 
134629 
135547 

0,01 36466 
137383 
i383oi 
139218 
i4oi35 

o,oi4io52 
141968 
143884 
i438oo 
144716 

o,oi4563i 
146546 
147460 
148375 
149288 

0,0l50203 

i5i  ii5 
1 52038 
i53g4i 
1 53854 

0,0154766 
155678 
1 56589 
1 57500 
i584ii 

0,0159322 
160333 
161142 
162052 
162961 

0,0163870 

164779 
165688 
166596 
167504 
o.oi684i3 


926 
925 
925 
925 

925 

924 
933 
924 
923 

923 

922 
933 
933 
921 

921 

921 
921 
921 
920 

919 
920 
919 
919 
gi8 

919 

917 
918 

917 
917 

917 
916 
gi6 
gi6 
916 

9i5 

915 
914 
gi5 
9'3 

914 

9i3 
gi3 
9i3 
913 

912 
912 
911 
9" 
9'i 

9" 
gio 
gio 
910 
909 
9°9 

909 
909 
908 
go8 

908 

007 


h 

H 


o,oi8û 

0181 

0183 
oi83 
0184 

0,01 85 
0186 
0187 
0188 
0189 

0,0190 
0191 
0192 
0193 
0194 

0,0195 
0196 
0197 
0198 
0199 

0,0200 
020 
0202 

0203 

0204 

0,0205 
03o6 

0307 

0308 

0309 

0,0210 

0211 

0312 
03l3 
03l4 

0,03 1 5 
0216 
0217 

0218 

02ig 

0,0220 
0221 

0333 
0233 
023 

0,0225 
0226 
0327 
0228 
0229 

0,033o 
023l 
0233 

0233 
0334 

0,0335 
0236 
0337 
0238 

0239 

0,0240 


Log.  yy 
Log.  YY 


0,0168412 
169319 
170226 
171 i33 
172039 

0,0172945 
i7385i 

174757 
175662 
176567 

0,0177471 
178376 
179280 
i8oi83 
181087 

0,0181990 
182893 
183796 
184698 
i856oo 

o,oi865oi 
187403 
i883o4 
189205 
190105 

0,0191005 
igigo5 
ig28o5 
193704 
ig46o3 

0,0195502 
196401 

197299 
198197 

199094 

o>oi99992 
20088g 
201785 
202682 
203578 

0,0204474 
205369 
206264 
207159 
2o8o54 

0,0208948 
209843 
210736 
2ii63o 

212523 

0,021 34 1 6 
2 1 4309 

2l520I 

216093 
2i6g85 

0,0217876 
218768 
219659 
220549 

23l44o 
0,02  3333o 


Diir. 


9"7 
907 
907 
906 

906 

go6 
906 
9o5 
905 

go4 

905 
904 
903 
904 

903 

go3 
go3 
go2 
902 

901 

go2 
go  I 
901 
goo 

goo 

goo 
900 
899 


898 
898 
897 


897 
896 
897 
896 

896 

895 
8g5 
8g5 
8g5 

894 

8g5 
8g3 
894 
8g3 

893 

893 
892 
892 
892 

8gi 
8g2 
891 
890 


8qo 


TABLE  VIII.  —  For  an  Ellipsis  or  Hyperbola. 

This  tabic,  with  Table  IX.,  X.,  are  for  computinE;  the  elements  of  the  orbit,  when  there  are  given  the  two  railii 
r,  r'  ;  the  iiicliulcd  heliocentric  arc  v'  —  v=  if,  and  the  time  t  of  describing  that  arc,  expressed  in  days. 


y 

H 


0,0240 
0241 
0343 
0343 
0344 

0,0345 
0246 
0347 
0248 
0349 

o,o35o 

025l 

0252 
0253 
0254 

0,0255 
0256 
0257 
0258 
0259 

0,0260 
0261 
0263 
0363 
0364 

0,0265 
0266 
0267 
0268 
0269 

0,0270 
0271 
0272 
0273 
0274 

0,0275 
0276 
0277 
0278 
0279 

0,0280 
0281 
0282 
0283 

0284 

0,0285 
0286 
0287 
0288 
0289 

0,0290 
0291 
0292 
0293 
02g4 

o,02g5 
0296 
0297 
0298 
029g 

o,o3oo 


Log. 
Log. 


yy 

YY 


0^333330 
223220 
224109 
224998 
225887 

0,0236776 
227664 
228553 
22g44o 
23o328 

0,023 1 21 5 

233I03 

333988 

233875 
234761 

0,0235647 
236532 

237417 
238303 
239187 

0,024007 1 
24og56 
241839 
242723 
243606 

0,024448g 
245372 
246254 
2471 36 
248018 

o,o348goo 
349781 
350663 
25 1 543 
253423 

o,o2533o4 
254i83 
255o63 
255942 

256822 
0,0257700 

258579 
259457 
260335 
261213 

0,0262090 
262g67 
263844 
364721 
2655g7 

0,0266473 
26734g 
268224 
269099 
269974 

0,0270849 
271733 
373597 
273471 
274345 

0,0375218 


890 
889 
889 
889 

88g 

888 
868 
888 
888 

887 

887 
886 
887 
886 

886 

885 
885 
885 
885 

884 

885 
883 
884 
883 

883 

883 
882 


881 
880 


879 
880 
879 
880 


879 
878 
878 
878 

877 

877 
877 
877 
876 

876 

876 
875 
8-5 
875 

875 

874 
874 
874 
874 
873 
873 


y 

H 


o,o3oo 
o3oi 
o3o3 
o3o3 
o3o4 

o,o3o5 
o3o6 
o3o7 
o3o8 
o3o9 

o,o3io 
o3ii 

03l3 

o3i3 
o3i4 

o,o3 1 5 
o3i6 
o3i7 
o3i8 
o3i9 

o,o32o 
o32i 

o322 

o323 
o324 

o,o325 
0326 
0327 
o328 
0329 

o,o33o 
o33i 
o332 
o333 
o334 

o,o335 
d336 
o337 
o338 
0339 

o,o34o 
o34i 
o342 
0343 
o344 

o,o345 
o346 
o347 
o348 
0349 

o,o35o 
o35 
o352 
o353 
o354 

o,o355 
o356 
0357 
o358 
o35g 

o,o36o 


Log.  yy 
Log.  YY 


0,02753:8 
2760g  I 
276964 
277836 
278708 

o,027g58o 
280452 
28i323 
283194 
283o65 

0,0283936 
284806 
285676 
386546 
287415 

0,0288284 
289 r53 
290022 
290890 
391758 

0,0292626 
293494 
294361 
395238 
396095 

0,0396961 
397827 
2986g3 

299559 
300424 

O,o3oi2go 
3o2i54 
3o3oig 
3o3883 
3o4747 

o,o3o56ii 
306475 
307338 
308201 
3ogo64 

0,0309926 
310788 
3ii65o 

3l35l3 

3 I 3373 

o,o3 14234 
3i5og5 
3i5g56 
3i68i6 
3 1 7676 

o,o3i8536 
3ig3g6 
330355 
321114 
331973 

o,o32283 
323689 
334547 
3254o5 
326262 

0,0327120 


Dim 


873 
S73 
872 
872 

872 

872 
871 
871 
871 


870 
870 
869 


86g 
868 
868 

868 

868 
867 
867 
867 

866 

866 
866 
866 
865 

866 

864 
865 
864 
864 

864 

864 
863 
863 
863 

862 

862 
862 
862 
861 

861 

861 
861 
860 
860 

860 

860 
859 
859 
859 

858 

858 
858 
858 
857 
858 
856 


H 


o,o36o 
o36i 
o362 
o363 
o364 

o,o365 
o366 
0367 
o368 
0369 

0,0370 
0371 
0372 
0373 
0374 

0,0375 
0376 
o377 
0378 
0379 

o,o38o 
o38i 
o382 
o383 
o384 

o,o385 
o386 
0387 
o388 
0389 

0,0390 
o3gi 
0392 
0393 
o3g4 

o,o3g5 
0396 
0397 
0398 
o3gg 

o,o4oo 

o,o4i 

043 

043 

o44 

o,o45 
o46 
o47 
o48 
049 

o,o5o 
o5i 
o52 
o53 
o54 

o,o55 
o56 
o57 
o58 
059 

0,060 


Log.  yy 
Log.  YY 


0,0327120 

327g76 
328833 
32968g 
33o546 

o,o33i4oi 
332257 
333ii2 
333967 
334822 

0,0335677 
336531 
337385 
338239 
33gog2 

o,o33gg46 
340799 
34i65i 
3425o4 
343356 

0,0344208 
345o59 
34591 1 
346763 
347613 

o,o348464 
34931 
35oi64 
35ioi4 
35i864 

o,o3527i3 
353562 
35441 
355259 
356io8 

0,0356956 
357804 
358651 
359499 
36o346 

0,0361192 
369646 
378075 
386478 
394856 

0,0403209 
4ii537 
419841 
438121 
436376 

0,0444607 
452814 
460998 
469157 
477294 

o,o4854o7 
493496 
5oi563 
509607 
517628 

0,0525626] 


Diir. 


856 
857 
856 
857 

855 

856 
855 
855 
855 

855 

854 
854 
854 
853 

854 

853 
852 
853 
852 

852 

85i 
852 
85i 
85i 

85i 

85o 
85o 
85u 
85û 

849 

849 
849 
848 
849 


847 
848 
847 
846 

8454 

8429 
84o3 
8378 

8353 

8328 
83o4 
8280 
8255 

833i 

8207 
8184 
8i5g 
8137 

8ii3 


8067 
8044 
8021 

7998 

7976 


h 
H 


0,060 
061 
062 
o63 
064 

o,o65 
o(i6 
067 
068 
069 

0,070 
071 
072 
073 
074 

0,075 
076 
077 
078 
079 

0,080 
081 
082 
o83 
084 

0,0 
086 
087 
088 
089 

0,090 
09 

09 

og3 

og4 

0,095 
096 
097 
098 

099 

0,100 
101 
102 
io3 
io4 

o,io5 
106 
107 
loi 
109 

0,110 
II I 

J  13 

ii3 
ii4 

o,ii5 
116 
117 
118 

i'9 
0,120 


Log. 
Log. 


yy 

YY 


0,0525626 
533602 
541 556 
549488 
557397 

o,o565285 
573 1 5o 
58o9g4 
588817 
596618 

0,0604398 
612157 
6ig8g5 
627612 
6353o8 

o,o642g84 
65o63g 
658274 
665888 
673483 

0,0681057 
688612 
6g6 1 46 
70 366 1 

711157 

0,0718633 
736ogo 
733527 
74og45 
748345 

0,0755725 
763087 
770430 
777754 
785060 

0,0792348 
799617 
806868 
8i4ioi 
82i3i6 

o,o8285i3 
8356g3 
842854 

849999 
857125 

0,0864335 
871327 
878401 
885459 
892500 

o,o8gg523 
go653o 
gi352o 
920494 
927451 

0,0934391 
g4i3i5 
948223 
955114 
961990 

0,0968849 


Difl'. 


7976 
7954 
7932 

7909 

7888 

7865 
7844 
7823 
7801 

7780 

7759 
7738 
7717 
7696 

7676 

7655 
7635 
7614 
7595 

7574 
7555 
7534 
75i5 
7496 

7476 

7457 
7437 
7418 
7400 

7380 

7362 
7343 
7334 
73o6 

7288 

7269 
725i 
7233 
72i5 

7>97 
7180 
7161 
7145 
7126 

7110 

7092 
7074 
7o58 
7041 

7023 

7007 
Oygo 
6974 
6957 

6940 

6924 
6908 
68gi 
6876 
6859 
6843 


TABLE   VIII.  —  For  an  Ellipsis  or  Hyperbola. 

elements  of  the  orbit   when  theie  are  given  tlie  two  radii 
time  t  of  describing  that  arc,  expressed  in  days. 


This  table,  with  Table  IX.,  X.,  are  for  computing  the 
?■,  r'  ;  tlie  included  heliocentric  arc  v'  —  t)  :=  2/",  and  the 


h 

H 


123 

124 

0,125 
126 
127 
128 
129 

o,i3o 
i3i 

1 32 

i33 
1 34 

0,1 35 
i36 

i37 

1 38 

1 39 

o,i4o 
i4i 
142 
J  43 

o,i45 
i46 
147 
1 48 
'49 

o.i5o 
)5i 

I  52 

i53 
1 54 

o,i55 

1 56 

1 57 

1 58 
i59 

0,160 
161 
162 
1 63 
164 

o,i65 
:66 
167 
168 
169 

0,170 
171 
172 
173 
174 

0,175 
176 

177 
178 

179 
0,1 


Log.  yy 
Log.  YY 


0,0968849 
975692 
982520 
989331 
996127 

0,1002907 
100967a 
1016421 
io23i54 
1029873 

0,1036576 
1043264 
1049936 
io56594 
1063237 

0,1069865 
1076478 
1083076 
1089660 
1096229 

0,1102783 
1109323 
1115849 
1122360 
1128857 

o,ii3534o 
1141809 
1 148264 
1 1 54704 
ii6ii3i 

0,1167544 
1173943 
1 180329 
II 8670 1 
1 193059 

0,1199404 
1205735 

1212053 

1 218357 

1224649 

0,1230927 
1237192 

1243444 

1249682 
1255908 

0,1262121 
1268321 
1274508 
) 280683 
1286845 

1,1292994 
1299131 
i3o5255 
1 3 1 1 367 
1 3 17466 

o,i323553 
1329628 
1335690 
1 34 1740 
1347778 

0,i3538o4 


Diff. 


6843 
6828 
6811 
6796 

6780 

6765 
674g 
6733 
6719 

6703 

6688 
6672 
6658 
6643 

6628 

66i3 
6598 
6584 
6569 

6554 

654o 
6526 
65ii 
6497 
6483 

6469 
6455 
6440 
6427 

64i3 

6399 
6386 
6372 
6358 

6345 

633i 
63i8 
63o4 
6292 

6278 

6265 
6252 
6238 
6226 

6213 

6200 
6187 
6175 
6162 

6149 
6i37 
6124 
6112 
6099 

6087 

6075 
6062 
6o5o 
6o38 
6026 
6014 


h 
H 


Log.  yy 
Log.  YY 


0,180 
181 
182 
i83 
184 

o,i85 
186 

187 

I  ,SH 
iSy, 

Ojigo 

191 
192 
193 
194 

0,195 
196 

197 
198 

199 

0,200 
201 
20a 
2o3 

204 

o,ao5 
206 
207 
208 
209 

0,210 
211 
212 

2l3 

214 

0,2l5 

216 
217 

218 
219 

0,220 

221 
22a 
223 
224 

0,225 
226 
227 
228 
229 

o,23o 

23l 
232 

233 
234 

0,235 
236 
237 
238 
239 

0,240 


o,i3538o4 
1359818 
1365821 
1371811 
1377789 

o,i383755 
1 3897 10 
1395653 
i4oi585 
1407504 

o,i4i34i2 
1419309 
i425ig4 
143 1 068 
143693 

0,1442782 
1448622 
1454450 
1460268 
1466074 

0,1471869 
1477653 
1483427 
14891 
1494940 

o,i5oo68i 
1 5o64 1 1 
1 5 1 2 1 3o 
i5i783S 
1523535 

0,1529222 
1534899 
i54o564 
1546220 
i55i865 

0,1557499 
1 563123 
1568737 
1 574340 
1579933 

o,i5855i6 
1591089 
1596652 
1602204 
1607747 

o,i6i3279 
1618802 
i6243i5 
1629817 
i6353io 

0,1640793 
1646267 
i65i73o 
1657184 
1662628 

o,i66So63 
1673488 
1678903 
i6843og 
1689705 

0,1695092 


Diff. 


A 
H 


6oi4 
6oo3 
5990 
5978 

5966 

5955 
5943 
5932 
5919 

5908 

5897 
5885 
5874 
5863 

585i 

584o 
5828 
58i8 
58o6 

5795 

5784 

5774 
5762 
5751 

5741 

5730 
5719 
5708 
5697 

5687 

5677 
5665 
5656 
5645 

5634 

5624 
56i4 
56o3 
5593 

5583 

5573 
5563 
5552 
5543 

5532 

5523 
55i3 
55o2 
5493 
5483 

5474 
5463 
5454 
5444 

5435 

5425 
541 5 
5406 
5396 
5387 
5378 


0,2 
241 
242 
243 

244 

0,245 
246 
247 
248 
249 

o,25o 

25l 
253 

253 
254 

0,255 
256 

257 
258 
259 

0,260 
261 
262 
263 
264 

0,265 
266 
267 
268 
269 

0,270 
271 
272 
273 
274 

0,275 
276 
277 
278 
279 

0,280 
281 
28a 
283 
284 

0,285 
286 
287 
288 
289 

0,390 
291 
292 
293 
294 

0,295 
296 

297 
398 

299 
o,3oo 


Log.  yij 
Log.  YY 


0,1695092 
1 700470 
1705838 
1711197 
1716547 

0,1721887 
1727218 
i73a54o 
1737853 
I743i56 

o, 1748451 
1753736 
1759013 
1764280 
1769538 

0,1774788 
1780029 
1785261 
1 790483 
1795698 

o,i8oogo3 
1806100 
18112 
1816467 
i82i638 

0,1826800 
i83ig53 
1837098 
1842235 
1847363 

o,i852483 
i8575g4 
i8626g6 
I 8677g I 
1872877 

o,i877g55 
i883o24 
1888085 
1893138 
1898183 

0,1903220 
190824g 
igi326g 
igi828i 
ig23286 

0,1928382 
1933271 
1938251 
1943224 
1948188 

0,1953145 
1958094 
1963035 
ig67g68 
1972894 

0,1977811 
1982721 
1987624 
1992518 
i9g74o6 

0,3002285 


Diff. 


5378 

5368 
535g 
535o 

5340 

533 1 

5332 

53i3 
53o3 

53g5 

5285 

5277 
5367 
5258 

535o 

5341 

5332 
5222 

52i5 
52o5 

5197 

5i88 

5179 
5171 

5162 

5i53 
5i45 
5i37 
5i28 

5l20 

5iii 

5l02 

5095 
5o86 

5078 

5069 
5o6i 
5o53 
5o45 

5o37 

5029 
5o3o 
5oi3 
5oo5 

4996 


4973 
4964 

4957 

4949 
4941 
4933 
4926 

4917 
4910 
4903 
4894 
4888 
4879 
4873 


h 
H 


o,3oo 
3oi 
3n2 
3o3 
3o4 

o,3o5 
3o6 
3o7 
3o8 
3og 

0,3 10 

3ii 

3l2 

3i3 
3i4 

0,3 1 5 
3i6 
3i7 
3i8 
3ig 

0,320 

321 
323 

333 
324 

0,325 
326 
337 
338 
339 

o,33o 
33 1 
333 
333 
334 

0,335 
336 
337 
338 
339 

0,340 
341 
343 
343 
344 

0,345 
346 
347 
348 
349 

o,35o 
35i 
352 
353 
354 

0,355 
356 
357 
358 
359 

o,36o 


Log.   yy 
Log.  Y  Y 


0,2002285 
2007157 

2012031 
2016878 
2021727 

0,2026569 

2o3i4o3 
2o3623o 
ao4io5o 
2045862 

0,2050667 
2055464 
2060254 
2o65o37 
2069813 

0,2074581 
2079342 
2084096 
2088843 
2093583 

0,3098315 
2io3o4o 
2107759 
21 13470 
2 1 1 7 1 74 

0,3131871 

2126503 

2i3i345 
2135921 
2i4o5gi 

0,3145253 
2149909 
2154558 
2i5g3oo 
2103835 

0,2168464 
2173085 
2177700 
2i833o8 
2186910 

o,2i9i5o5 
3 1 g6og3 
2200675 
22o525o 
>i8 


0,2214380 
22i8g35 
2223483 
2338026 

2232561 
0,2  2370g  I 

234i6i3 

2246l3o 

225o64o 
2255i43 

o,235g64o 
3264i3i 
3368615 
2373og4 
3377565 

0,3383o3l 


Diff. 


4872 
4864 
4857 


4842 

4834 
4827 
4830 
4812 

48o§ 

4797 
479" 
4783 
4776 
4768 

4761 
4754 
4747 
473g 

4733 

4725 
4719 
4711 
4704 

4697 

4691 
4683 
4676 
4670 

4662 

4656 


4642 
4635 

4629 

4631 
46i5 
4608 
46o3 

45g5 

4588 
4582 
4575 
4568 

4562 

4555 
4548 
4543 
4535 

453o 

4522 

4517 
45io 
45o3 

4497 

4491 
4484 
4479 
4471 
4466 
445q 


TABLE  VIII. — For  an  Ellipsis  or  Hyperbola. 


This  table,  witli  Table  IX.,  X.,  arc  lor  computing  the  elements  of  the  orbit 
»•';  the  incliulcil  helion-iitric  arc  r'  —  !•  =  :>/,  ami  the  time  (  of  descril)iii{;  th 


,  when  there  are  given  the  two  radii 
at  arc,  expressed  in  days. 


h 

H 


o,3tx) 
301 
3(53 
363 
364 

0,365 
360 
367 
368 
369 

0,370 

37  > 
372 
373 
374 

0,375 
376 

377 
378 

379 

o,38o 
38 1 
382 
383 
384 

o,385 
386 
387 
388 
389 

0,390 
391 
392 
393 
394 

0,395 
391- 

397 
398 

399 

0,400 
4oi 
402 
4o3 
4o4 

o,4o5 
4o6 

407 
4o8 
409 

0,4 10 
4ii 

4l2 

4i3 
4i4 

o,4i5 
Aid 
417 
4i8 
419 

0.420 


Log.  yy 
Log.  YY 


0,2282031 
2286490 
2290943 
2295390 
2399831 

o,23o4265 
2308694 
23i3i  16 
2317532 
2321942 

0,2326340 

233o'743 
2335i35 
2339521 
2343900 

0,2348274 
2352642 
2357003 
236i359 
2365709 

0,2370053 
2374391 
2378723 
2383o5o 
2387370 

0,2391685 
2395993 
2400296 
2404594 
2408885 

0,24i3i7i 
2417451 
2421725 
2425994 
2430257 

0,24345:4 
243876O 
2443oi3 
2447252 
2451487 

0,2455716 
2459940 
2404 1 58 
2468371 
2472578 

0,2476779 
2480975 
2485i60 
2489351 
2493531 

0,2497705 
2501874 
25o6o38 
251019O 
2514349 

0,2518496 
2522638 
2526775 
2530906 
2535o32 

0,2539153 


4459 
4453 
4447 
4441 

4434 

4429 
4422 
4416 
44io 

44o4 

4397 
4392 
4386 
4379 
4374 

4368 
436 1 
4356 
435o 

4344 

4338 
4332 
4327 
4320 

43i5 

43o8 
43o3 
4298 
4291 

4286 
4280 
4274 
42C9 
4263 

4257 

4252 

4246 

4240 
4235 

4229 

4224 
4218 

42l3 

4207 
4201 

4196 
4I9I 

4i85 
4180 

4174 
4169 
4i64 
4i58 
4i53 

4i47 

4i42 
4i37 
4i3i 
4126 

4l2I 

4ti6 


h 
H 


0,420 
42 
422 
423 
424 

0,425 
426 

427 
428 
429 

o,43o 
43 1 
432 
433 

m 
0,435 

436 

437 
438 
439 

0,440 
441 
442 
443 
AAA 

0,445 


449 

o,45o 
45: 
452 
453 
454 

0,455 
456 
457 
458 
459 

0,460 
461 
462 
463 
404 

o,465 
400 
407 
468 
469 

0,470 
471 
4-2 
473 
474 

0,475 
47O 
477 
478 

479 
0,480 


Log.  yy 
Log.  YY 


0,2539153 
25433O9 
254737g 
255i485 
2555584 

0,2559679 
2503769 
25O7853 
2571932 
257600O 

0,2580075 
2584i39 
2588198 
2592252 
25ge3oo 

0,2000344 
2O04382 
2O08415 
2O 1 2444 
2G1O4O7 

0,2020480 
2O24499 
2028507 
2O32511 
26365o9 

o,264o5o3 
2644492 
2648475 
2O52454 
2650428 

o,200o397 
2664362 
2668321 
2672276 
2676226 

0,2680171 
2684111 
2O8804O 
2691977 
2695903 

0,2699824 
2703741 
2707652 
2711559 
2715462 

0,2719360 
2723253 
2727141 
2731025 
2734904 

0,2738778 
2742648 
27465 1 3 
2750374 
2754230 

0,2758082 
27O1929 

2765771 

2769609 

2773443 

0,2777272 


4ii6 
4iio 
4106 
4099 

4095 

4090 
4o84 

4079 
4074 

4069 

4064 
4059 
4o54 
4o48 

4044 

4o38 
4o33 
4029 
4023 

4019 

4oi3 
4008 
4oo4 
3998 

3994 

3989 
3983 

3979 
3974 

3969 

3965 

3959 
3955 
3950 

3945 

3940 
3935 
3931 
392e 

3921 

3917 
391 1 
3907 
3903 

3898 

3893 
3888 
3884 
3879 
3874 

3870 
3865 
386 1 
3850 

3852 

3847 
3842 
3838 
3834 
3829 
3834 


H 


0,480 
481 
482 
483 
484 

0,485 
480 
487 


0,490 
491 
492 
493 
494 

0,495 
496 
497 
498 
499 

o,5oo 
5oi 

502 

5o3 
5o4 

o,5o5 
5oO 
5o7 
5o8 
509 

o,5io 
5i 

5l2 

5i3 
5i4 

o,5i5 
5iO 
517 
5i8 
5ig 

0,520 

521 

522 
523 
524 

0,525 
526 
527 
528 
529 

o,53o 
53i 
532 
533 
534 

0,535 
536 
537 
538 
539 

0,540 


Log.  yy 

Log.  IT 


0,2777272 
2781 096 
2784916 
2788732 
2792543 

0,2796349 
2800152 
2803949 
2807743 
2811532 

o,28i53i6 
28 1 9096 
2822872 
2826644 
283o4ii 

0,2834173 
2837932 
2841686 
2845436 
28491 8 1 

0,2852923 
285O6O0 
2800392 
2804 1 2 1 
2867845 

0,2871505 
2875281 
2878992 
2882700 
2886403 

0,28901 
2893797 
2897487 
2901 174 
2go4856 

0,2908535 
2912209 
2915879 
2919545 
3923207 

0,2926864 
2930518 
2934168 
2937813 
2g4i455 

0,3945092 
2948726 
2952355 
2955981 
2959602 

0,2963220 
29O6833 
2970443 
2974049 
2977650 

0,2981248 
2984843 
2988432 
2992018 
2995600 

0,3999178 


Diir. 


3824 

3820 
38iO 
38ii 

38o6 
38o3 
3797 
3794 
3789 

3784 
3780 
3776 

3772 

3767 
3762 

3759 
3754 
3750 
3745 

3742 

3737 
3732 

3729 
3724 

3720 

371O 
371 1 
3708 
3703 

3O99 

3695 
3O90 
3087 
3682 

3079 

3O74 
3O70 
3000 
3002 

3057 

3654 
305o 
3045 
3642 

3637 

3634 
3629 
3626 
3621 

30i8 

36i3 
3O10 
36o6 
3O01 

3598 

3594 
3590 
3586 
3582 
3578 
35^4 


h 
H 


0,540 
54 1 
542 
543 
544 

0,545 
540 
547 
548 
549 

o,55o 
55i 
552 
553 
554 

0,555 
550 
557 
558 
559 

o,50o 
56 1 
502 
503 
504 

o,565 
566 
5O7 
568 
569 

0,570 
571 
572 
573 
574 

0,575 
57O 

577 
578 

579 

o,58o 
58 1 
582 
583 
584 

o,585 
586 
587 
588 
589 

0,590 
591 
592 
593 
594 

0,595 
596 

59' 
598 

599 
0.000 


Log.  yy 
Log.  YY 


0,2999178 
3002752 
3oo6323 
3009888 
3oi3452 

0,3017011 
3o2o566 
3024117 
3027664 
3o3i2o8 

o,3o34748 
3o38284 
3o4i8i6 
3045344 
3048869 

0,3052390 
3o55go7 
3059420 
30O2930 
3o66436 

0,3069938 
3073437 
307O931 
3o8o422 
3083910 

0,3087394 
3090874 
3094350 
3og7823 
3ioi2g2 

o,3io4758 
3108220 
3iii078 
3ii5i33 
3i 18584 

0,3l2203l 

3125475 

3i28gi5 
3i32352 
3 1 35785 

o,3i3g2i5 
3i43Ô4i 
3 1 46064 
3i4g483 
3152S98 

0,3 1 503 10 
3i5g7i9 
3i03i24 
3i66525 
3169933 

0,3 1733 18 
3 1 7O709 
318009O 
3i8348i 
3 1 8086 1 

0,3190239 
3193612 
3196983 
32oo35o 
3203714 

0,3207074 


3574 
3571 
3565 
3564 

3559 

3555 
355 1 
3547 
3544 

3540 

3530 
3532 
3528 
3525 

3521 

35i7 
35i3 
35io 
35oe 

35o2 

34gg 
34g4 
34gi 
3488 

3484 
3480 
3476 
3473 
3469 

3466 

3462 
3458 
3455 
345 1 

3447 

3444 
3440 
3437 
3433 

3430 

3426 
3423 
3419 
341 5 

3412 

3409 
34o5 
3401 
3398 

3395 

3391 
3387 
3385 
338o 

3378 

3373 
3371 
3367 
3364 
336o 


a26 


TABLE    IX.  —  For  an  Elliptical  Orbit. 


This 

table  is  used  in  connexion  witli  Ta 

Me  VIII.,  in 

inding  the  elements  of  tl 

e  orbit,  by 

means  of  the  two  radii 

r'.  )■  .- 

the  included  heliocentric  arc  v 

-«  =  2/, 

and  tlie  time 

t  of  describinn;  that  arc, 

in  days. 

. 

1 

Diff. 

X 

1 

UifT. 

73 
74 
76 

X 

1 

Diir. 
1 54 

X 

1 

Difl'. 

X 

1 

Diir. 

0,000 

0,0000000 

J 

0,060 

0,00021 3i 

0,120 

0,0008845 

0,180 

0,0020685 

244 
246 

0,340 

0,0038289 

346 
348 
35o 
352 

'    001 

0001 

I 

061 

2204 

121 

8999 

i55 

181 

20929 

241 

38635 

002 

0002 

062 

2278 

122 

gi54 

1 57 
i58 

182 

21175 

242 

38g83 

oo3 

ooo5 

0 
4 

o63 

2354 

123 

93 1 1 

i83 

21422 

247 
249 

243 

3g333 

004 

0009 

064 

243i 

77 

124 

9469 

184 

21671 

244 

39686 

5 

78 

i5g 

25l 

354 

o,oo5 

0,0000014 

7 
7 
9 

0,065 

o,ooo25og 

79 
81 

0,125 

0,0009628 

161 

o,i85 

0,0021922 

262 
264 
255 
258 

0,245 

O,oo4oo39 

355 
358 
35g 
36 1 

006 

0021 

066 

2588 

126 

09789 

162 

186 

22174 

246 

4o3g4 

007 

0028 

067 

2669 

82 

127 

ogg5i 

1 64 
i65 

187 

22428 

247 

40762 

008 

0037 

068 

2761 

83 

128 

ioii5 

188 

22683 

248 

4iiii 

009 

0047 

069 

2834 

12g 

10280 

189 

22g4i 

249 

41472 

10 

84 

167 

258 

363 

0,010 

0,0000057 

i3 

0,070 

0,0002918 

86 

o,i3o 

0,0010447 

168 

0,190 

0,0023  igg 

261 
262 
263 
266 

0,260 

o,oo4i836 

364 
367 
368 
371 

on 

0070 

i3 

071 

3oo4 

87 
89 

i3i 

1 061 5 

i6g 

191 

23460 

261 

42199 

012 

oo83 

i4 
16 

072 

3ogi 

1 32 

10784 

192 

23722 

262 

42666 

oi3 

0097 

073 

3i8o 

1 33 

10955 

171 
173 

193 

23g85 

253 

42934 

oi4 

oii3 

074 

326g 

1 34 

11128 

ig4 

24261 

2  54 

433o5 

17 

91 

173 

267 

372 

0,01 5 
016 

o,ooooi3o 
oi48 

18 
19 

0,075 
076 

o,ooo336o 
3453 

93 
93 
95 
97 

o,i35 
1 36 

0,001 i3oi 
"477 

176 

o,ig5 
1 96 

0,0024618 
24786 

268 

0,255 
256 

0,0043677 
44o5i 

374 
376 

377 
38o 

017 

0167 

077 

3546 

137 

1 1 654 

177 
178 
180 

197 

26066 

370 

257 

44427 

018 
019 

0187 
0209 

22 

078 
079 

364 1 
3738 

1 38 

1 39 

ii832 
1 20 1 2 

198 
199 

25328 
a56o2 

272 
274 

2  58 
269 

44804 
45i84 

22 

97 

181 

275 

382 

0,020 

0,000023 1 

1/Ï 

0,080 

o,ooo3835 

99 
100 

o,i4o 

0,0012193 

i83 
184 
i85 
188 

0,200 

0,0026877 

0,260 

0,0045666 

383 
385 
387 
3go 

021 

0255 

24 

25 

26 
28 

081 

3g34 

i4i 

12376 

201 

26154 

277 

261 

45g49 

022 

023 

0280 
o3o6 

082 
o83 

4o34 
4i36 

102 
io3 

142 
143 

i256o 
12745 

202 
2o3 

26433 
26713 

279 
280 
282 

262 
263 

46334 
46721 

024 

o334 

084 

4239 

i44 

12933 

2o4 

26996 

264 

471 1 1 

28 

io4 

188 

283 

391 

0,025 

o,oooo362 

32 

o,o85 

0,0004343 

io5 

o,i45 

0,OOl3l2I 

0,205 

0,0027378 

286 
287 
288 

0,265 

0,0047602 

392 
396 
397 
399 

026 

o3g2 

086 

4448 

107 
108 

1 46 

i33ii 

IQO 

206 

27664 

266 

47894 

027 

0423 

087 

4555 

1 47 

i35o3 

iga 
193 
ig5 

207 

27861 

267 

4828g 

028 

0455 

34 

088 

4663 

1 10 

1 48 

13696 

208 

28139 

268 

48686 

029 

0489 

089 

4773 

149 

1 389 1 

209 

28429 

290 

269 

4go85 

34 

III 

ig6 

293 

4oo 

o,o3o 

0,0000623 

36 

37 
38 
4o 

o,ogo 

o,ooo4884 

112 

0,1 5o 

0,0014087 

198 

0,210 

0,0028722 

293 
296 

0,270 

o,oo4g485 

4o3 
4o4 

407 
408 

o3i 

o559 

091 

4gg6 

ii3 

i5i 

14285 

211 

2goi5 

271 

49888 

032 

0596 

092 

5 1 09 

ii5 

l52 

14484 

'99 

212 

2g3i  1 

273 

60292 

o33 

0634 

093 

5224 

117 

1 53 

14684 

200 

2l3 

29608 

297 

273 

60699 

o34 

0674 

094 

5341 

1 54 

14886 

202 

2l4 

29907 

299 

274 

61 107 

4o 

117 

204 

300 

410 

o,o35 

0,0000714 

42 
43 
45 
45 

0,ng5 

o,ooo5458 

"9 
120 

o,i55 

o,ooi5ogo 

205 

0,2 1 5 

o,oo3o207 

302 
3o5 
3o5 
308 

0,276 

0,oo5i5i7 

4i3 
4i4 
416 
418 

o36 

0756 

096 

5577 

1 56 

i52g5 

216 

30609 

276 

5ig3o 

037 

0799 

097 

5697 

122 

1 57 

i55o2 

207 

208 

217 

3o8i4 

277 

63344 

o38 

0844 

og8 

58ig 

123 

1 58 

16710 

218 

31119 

278 

62760 

o3g 

0889 

099 

5942 

159 

16920 

210 

219 

31427 

279 

53178 

47 

124 

211 

309 

420 

o,o4o 

0,0000936 

48 
5i 

0,100 

0,0006066 

126 

0,160 

o,ooi6i3i 

2l3 
2l5 

216 

0,220 

o,oo3 1 736 

3ii 

313 

3i5 
316 

0,280 

o,oo635g8 

422 

04 1 

0984 

lOI 

6192 

127 
129 
i3o 

161 

i6344 

221 

32047 

281 

54020 

042 

io33 

102 

63ig 

162 

i655g 

222 

3235g 

282 

54444 

424 
426 
428 

043 

1084 

io3 

6448 

1 63 

16775 

223 

02674 

283 

54870 

044 

ii35 

104 

6578 

164 

16992 

217 

224 

32990 

284 

552g8 

53 

i3i 

219 

3i8 

43o 

0,045 

0,0001188 

54 
56 
56 
58 

o,io5 

0,0006709 

1 33 

o,i65 

0,0017211 

0,225 

o,oo333o8 

319 
333 
333 
325 

0,285 

0,0066728 

432 
434 
436 
438 

o46 

1242 

106 

6842 

1 34 
i35 

166 

17432 

221 

226 

33637 

286 

66160 

047 

1298 

107 

6976 

167 

17654 

222 
224 
225 

227 

33g49 

387 

565g4 

048 

1 354 

108 

7rii 

1 37 

168 

17878 

228 

34272 

288 

57o3o 

049 

l4l2 

109 

7248 

169 

i8io3 

22g 

34597 

289 

57468 

59 

1 38 

227 

327 

440 

o,c5o 

0,0001471 

61 
61 
63 
64 

0,110 

0,0007386 

i4o 

0,170 

o.ooi833o 

228 

o,23o 

o,oo34g34 

338 
33o 
332 

0,290 

0,0067908 

442 
446 
446 
448 

o5i 
o52 

1 532 

1593 

III 

113 

7526 
7667 

i4i 
142 

171 
172 

18558 
18788 

23o 

232 

23l 
232 

35252 
35582 

291 
292 

6835o 
587g5 

o53 

i656 

ii3 

7809 

1 44 

173 

19020 

233 

233 

35914 

334 

3g3 

59241 

o54 

1720 

ii4 

7953 

■74 

19253 

234 

36348 

2g4 

69689 

65 

i45 

234 

336 

45o 

o,o55 

0,0001785 

67 
68 
69 

71 

o,ii5 

o,ooo8og8 

T  4-! 

0,175 

0,0019487 

237 
237 
240 

24l 

243 
244 

0,235 

o,oo36584 

337 
339 
341 
343 
345 
346 

0,395 

0,0060139 

4  53 
454 
457 
458 
46 1 

o56 

i852 

116 

8245 

1 48 

176 

19724 

236 

36931 

296 

60691 

o57 

1920 

117 

8393 

177 

1 996 1 

237 

37360 

297 

61045 

o58 
059 

■989 
2060 

118 
"9 

8542 
86g3 

149 
i5i 

l52 

178 
179 

20201 
20442 

238 
239 

37601 
37944 

298 
299 

61602 
61960 

0,060 

0,0002 1 3i 

71 

73 

0,120 

0,0008845 

i54 

0,180 

o,oo2o685 

0,240 

0,0038289 

o,3oo 

0,0062431 

TABLE    X.  —  For  a  Hyperbolic  Orbit. 


This 

tabic  is  used  in  connexion  with  Table  VIII.,  in  fimlins;  the 

elenie 

nts  of  the  orbit  bv 

means  of  th 

c  two  radii  »',  r  ; 

the  iiic 

viiied  heliocentric 

arc  I)' 

-V=7f, 

uid  tl 

e  time 

t  of  describ 

ing  that  arc, 

in  days. 

z 

^ 

Ditr. 

^ 

Diff. 

~ 

s" 

Dili'. 

~ 

^ 

Dili'. 
178 

~ 

s" 

Dill'. 

0,000 

0,0000000 

0,060 

0,0001988 

66 

67 
68 
68 

0,120 

0,0007698 

,  „  / 

0,180 

0,0016783 

o,34o 

0,0028989 

001 

0001 

I 

c6i 

2o54 

121 

7822 

134 
126 
126 
128 

181 

16960 

241 

29166 

337 
2  38 

002 

0002 

I 
3 

4 

062 

2121 

122 

7948 

183 

'7139 

17g 
180 
181 

242 

29894 

oo3 
004 

ooo5 
0009 

o63 
064 

2189 
2257 

123 

124 

8074 
8202 

1 83 

1 84 

'73ig 
I750Ô 

243 
244 

39638 

29852 

3  29 
239 

5 

70 

128 

181 

281 

o,oo5 

0,0000014 

6 
8 
8 

o,o65 

0,0002327 

0,135 

o,ooo833o 

o,i85 

0,0017681 

i83 
1 83 
184 
i85 

0,245 

o,oo3oo83 

281 
281 

283 
233 

006 

0020 

066 

2398 

71 

136 

8459 

139 
i3i 
i3i 

l33 

186 

I7S64 

346 

3o3i4 

007 
008 

0028 
oo36 

067 
068 

2470 
2543 

72 
73 

127 
138 

8590 
8721 

187 
188 

18047 
18281 

247 
34s 

3o545 
30778 

009 

0046 

10 

069 

2617 

74 

139 

8853 

189 

I84I6 

249 

3ioii 

II 

74 

i33 

186 

234 

0,010 
on 

0,0000057 
0069 

12 
i3 

i4 
i5 

0,070 
071 

0,0002691 
2767 

76 

o,i3o 
i3i 

0,0008986 
9120 

i34 
i35 
i35 
1 37 

0,190 
191 

0,0018602 

1878g 

187 
187 
189 
i8g 

o,25o 

25l 

0,0081245 
3 1480 

335 
386 

OI3 

0082 

072 

2844 

77 

l32 

9255 

193 

18976 

253 

81716 

286 

287 

oi3 

0096 

073 

3922 

78 

1 33 

9390 

193 

19165 

253 

31953 

oi4 

OIII 

074 

3ooi 

79 

1 34 

9527 

194 

19354 

254 

82189 

16 

80 

1 38 

190 

288 

0,01 5 

0,0000127 

18 

0,075 

o,ooo3o8i 

81 
82 
83 
84 

o,i35 

0,0009665 

1 38 
i4o 
i4o 
i4i 

0,195 

o,ooig544 

0,255 

0,0083437 

289 
289 

34l 

016 

oi45 

076 

3162 

i36 

09803 

196 

.g735 

'9' 

256 

82666 

017 

0164 

'9 

077 

3244 

1 37 

09943 

197 

19926 

'9' 
ig3 
ig3 

257 

82905 

018 

oi83 

'9 

078 

3327 

138 

ioo83 

198 

20119 

258 

33i46 

oig 

0204 

21 

079 

3411 

1 39 

10334 

199 

203l2 

259 

33387 

3^1 

32 

85 

142 

ig5 

24l 

0,020 
021 

0,0000226 
0249 

23 
34 
25 

0,080 
081 

0,0003496 
3582 

86 

o,i4o 
i4i 

o,ooio366 
loSog 

143 
i44 
145 
i46 

0,200 
201 

0,0020507 

20703 

195 
195 

0,360 
361 

0,0088628 
88871 

243 
243 

344 
245 

022 

0273 

082 

3669 

87 
88 
89 

l43 

10653 

303 

30897 

363 

34114 

023 

0398 

o83 

3757 

i43 

10798 

203 

2iog4 

'97 
198 

263 

34858 

024 

o325 

27 

084 

3846 

144 

10944 

204 

21392 

264 

84608 

27 

90 

i47 

198 

345 

0,025 

o,oooo352 

o,o85 

0,0003936 

0,145 

0,0011091 

l47 

1 49 
i4g 

o,3o5 

0,0021490 

0,265 

0,0084848 

346 
247 
248 
24g 

026 

o38i 

29 

086 

4027 

91 

1 46 

1 1 338 

206 

21689 

199 

266 

35094 

027 

o4io 

29 

3i 

32 

087 

4119 

9' 
93 

i47 

ii387 

207 

2188g 

300 

267 

35341 

028 

0441 

088 

4212 

148 

1 1 536 

208 

22ogo 

301 

368 

3558g 

029 

04-3 

089 

43o6 

94 

149 

1 1687 

IJI 

209 

222gi 

201 

269 

35888 

33 

95 

i5i 

2o3 

249 

o,o3o 

o,oooo5o6 

33 
36 
36 
37 

0,090 

o,ooo44oi 

95 
97 
98 

o,i5o 

0,001 1838 

l53 

0,3I0 

o,oo224g4 

2n3 
204 
2o5 
2o5 

0,270 

0,0086087 

o3i 
o32 

0539 
0575 

091 
092 

44g6 
4593 

i5i 

l53 

1 1990 
12143 

1 53 
i53 

21  1 
212 

236g7 
33901 

271 
272 

36837 
36587 

25o 

353 
352 

o33 

061 1 

093 

4691 

1 53 

13296 

i55 

2l3 

23io6 

273 

86889 

o34 

o648 

094 

4790 

99 

1 54 

i345i 

2l4 

233ii 

274 

37091 

38 

100 

1 56 

207 

253 

o,o35 

0,0000686 

4o 
40 
4i 
43 

0,095 

o,ooo48go 

o,i55 

0,0013607 

1 56 
1 58 

1 58 

1 59 

0,21  5 

o,oo235i8 

0,275 

0,0087844 

254 
254 
255 
256 

o36 
o37 
o38 

0726 
076e 
0807 

096 
097 
098 

4991 
5og2 
6195 

lOI 
lOI 

io3 
104 

1 56 

1 57 

1 58 

12763 
I2g2i 
1 307g 

216 
217 
218 

23725 

23932 
34142 

207 

207 
210 

276 

277 
378 

37598 
87852 
88107 

039 

08  5o 

099 

529g 

1 59 

1 3338 

219 

24352 

210 

279 

38363 

44 

io4 

160 

210 

257 

o,o4o 

0,0000894 

44 
46 
47 
48 

0,100 

o,ooo54o3 

106 

0,160 

o,ooi33g8 

161 

0,220 

0,0034562 

0,280 

0,0088620 

257 

258 
35g 
360 

o4i 

0938 

101 

5509 

161 

i355g 

ifio 

231 

24774 

2  I  2 

281 

38877 

042 

0984 

102 

56i6 

107 

163 

1373 1 

1U2 
162 
164 

233 

24986 

213 
2l3 
213 

283 

89135 

043 
o44 

io3i 
1079 

io3 
io4 

5723 
5832 

107 
log 

1 63 
164 

1 3883 
i4o47 

233 
224 

25199 

35413 

283 
284 

39894 
89654 

49 

log 

164 

2l5 

260 

0,045 

0,0001128 

5o 

o,io5 

o,ooo594i 

o,i65 

0,00 1 42 1 1 

J  66 

0,225 

0,0025637 

2l5 

216 

0,285 

0,0039g i4 

261 
262 
263 
263 

046 

1 178 

5i 

106 

6o53 

III 

166 

14377 

166 

226 

35842 

286 

40175 

047 

1229 

52 

53 

107 

6i63 

II I 

167 

14543 

167 
168 

227 

26o58 

387 

40437 

o48 

1281 

108 

6275 

IT2 

ii4 

168 

14710 

228 

26275 

217 

218 

388 

40700 

049 

1 334 

109 

6389 

i6g 

14878 

229 

36493 

289 

40968 

55 

ii4 

169 

218 

264 

o,o5o 

0,0001389 

55 

0,110 

o,ooo65o3 

ii5 
116 

0,170 

o,ooi5o47 

169 

171 
171 
172 

o,23o 

0,0026711 

0,390 

0,0041337 

364 
366 
366 
367 

o5i 
o53 

1 444 
i5oo 

56 
58 

III 
112 

6618 
6734 

171 
173 

i53i6 

1 5387 

33l 
233 

26931 

27l5l 

220 

2gi 
293 

41491 
41757 

o53 
o54 

1 558 
1616 

58 

ii3 

ii4 

685 1 
696g 

"7 
118 

173 
174 

i5558 
1 5730 

233 
234 

37371 
27593 

220 
222 

2g3 
294 

43038 

422go 

59 

"9 

173 

223 

267 

o,o55 

0,0001675 

61 
62 
62 

64 
64 
66 

0,1 1 5 

0,0007088 

0,175 

0,001 5903 

174 
175 
176 
176 
178 
,78 

0,235 

0,0027816 

223 

224 
224 
236 
226 
327 

o,3g5 

0,0042557 

269 

269 
269 

271 
271 

o56 

057 
o58 
o5g 

1736 
1798 
i860 
1924 

116 

117 
118 
"9 

7208 
733g 
745 1 

7574 

1 20 
121 
122 

123 

124 

134 

176 
177 
178 
17g 

16077 
16352 
16438 
16604 

2  36 
237 
338 
239 

28039 
28363 
38487 
38713 

296 

297 
298 

299 

42826 

43og5 
43864 
43635 

0,060 

0,0001988 

0,120 

0,0007698 

0,180 

0,0016783 

0,240 

0,0038989 

o,3oo 

0,0048906 

PRECEPTS  FOR  THE  USES  OF  TABLES  XI.  AND  XII. 

These  Tiibles  are  inserted  for  the  purpose  of  changing  the  arcs  of  the  centesimal  division  of  the  quadrant  into  sexagesimals. 

Table  XI.,  is  divided  into  three  distinct  parts.  The  first  part  gives  the  degrees  and  minutes,  in  sexagesimals,  for  every  degree  of 
the  centesimal  division,  from  0°  to  .399°  ;  the  tens  being  in  the  side  column,  and  the  units  at  the  top.  Thus  we  see  by  inspection,  that 
260°  =  234'' 00'"  ;  261°  =  2.34'' 54"' ;  &c.  The  second  part  gives  the  minutes  and  seconds  in  sexagesimals,  corresponding  to  the 
centesimal  division  from  0'  to  99';  the  tens  of  minutes  being  at  the  side,  and  the  units  at  the  top  ;  thus  60' =  32'"  24*;  61 '  =  .32"' 56  ,4: 
&c.  The  third  part  gives  the  seconds  and  decimals  in  sexagesimals,  corresponding  to  the  centesimal  division,  from  0"  to  99"  ;  the  tens 
of  seconds  being  at  the  side  and  the  units  at  the  top;  thus  40"  =  12%  960;  41"  =  13%  284;  &c.  The  two  following  examples,  show 
its  use  in  more  complicated  cases;  they  require  no  particular  explanation. 


EXAMPLE     I  . 

Change  agS     21' 17"  into  sexagesimals. 

Table  XI.    293°  =  26^  A"  00* 
21'  =  II     20,4 

17"  =  5,5o8 


293''2i'i7"  =263''53'"25',9o8 


EXAMPLE     II. 

Change  263    53""  25',  908  into  centesimals. 


Table  XI.     263"^  42"' 


=  293°  00'  00" 


Remainder,  ii""  25  ,  908 

Table    XI.  11'"  20',  4       =     o    21     00 


Remainder  Table  XI.    5^,  5o8  = 


17 


263'^  53°"  25*  908  =2g3°  21'    17" 


Table  XII.,  gives  the  seconds  and  decimals,  in  sexagesimals,  for  every  second  of  the  centesimal  division,  from  0"  to  999";  the  tens 
being  in  the  side  column  and  tlie  units  at  the  top.  It  is  computed  by  the  rule  s  =  0,324.  c;  s  being  the  number  of  sexagesimal  seconds 
corresponding  to  c  In  centesimal  seconds.  Hence  we  have  by  inspection  570"  =  184%  680  ;  571"  =  185*,  004  ;  &c.  If  we  change  the 
decimal  point,  three  places  to  the  left,  we  shall  get,  from  the  table,  by  inspection,  the  value  of  every  thousandth  part  of  1"  from  0",001 
to  0",999.  Thus  we  have,  by  using  the  same  numbers  as  before,  0",.570  =  O", 184680  ;  0",571  =  0',185004  ;  &c.  In  like  manner,  by 
changing  the  decimal  point  to  the  left  6  units  we  get  the  values  from  0",000001  to  0",000999;  &c.  We  may  also  change  the  decimal 
point  to  the  right,  if  larger  numbers  are  wanted. 


EXAMPLE      III. 

Change  327",  345  into  se.xagesimals. 
327",  000  :=:  io5*,  948 
,345  111780 


327",  345  =  106*,  059780 

EXAMPLE     V. 
Change  327345"  into  sexagesimals. 
327000"  =  105948' 
345"=        in*,  780 


327345"  =  io6o59%  780 

EXAMPLE     VII. 

Change  o",  6443o2  into  sexagesimals. 

o",  644       =  o*,  2o8656 
o",  ooo3o2  =  q8 


O",  644302   =  Q,\  208754 


EXAMPLE     IV. 

Change   106*,  059780  into  centesimal  seconds. 
Table  XII.     io5*,  948        =  327",  000 
Table  XII.  111780=  345 


106*,  059780  =  327",  345 

EXAMPLE      VI. 

Change  106059*,  7^°  ''^*''  centesimal  seconds. 
Table  XII.     105948*  =  327000" 

Table  XIII.        in',  780  =        345" 

106059*.  780  =  327345" 

EXAMPLE     VIII. 

Change  o",  076897  into  sexagesimals, 
o",  076       =  o',  024624 
o",  000897  =  291 


o",  076897  =  o",  024915 


Table  XII.,  has  been  found  very  convenient  in  making  the  reductions  of  the  planetary  inequalities,  in  this  volume,  from  centesimal 
to  sexagesimal  seconds,  to  six  places  of  decimals,  as  in  the  two  last  examples.  Since  it  is  easy  (0  obtain  the  sum  of  the  two  parts  of  the 
fraction,  without  the  trouble  of  writing  them  down  separately;  the  last  part  of  the  fraction  being  generally  so  small  that  it  is  easy  to 
add  it  to  the  large  tabular  number  corresponding  to  the  first  part.  Thus  in  example  VII.,  the  number  98  is  easily  added  lo  0,208656, 
to  obtain  0,208754,  by  mere  inspection.  The  numbers  given  in  this  volume  were  in  the  first  place  computed  from  the  table,  and  then 
verified  by  a  numerical  calculation  ;  found  by  putting  .s'  =  0,3  c  and  s  =  *'  +  0,08  s'.  So  that  instead  of  writing  down  the  number  c 
and  then  multiplying  it  by  0,324  ;  we  may  write  down,  in  the  first  instance  0,3  c  ;  and  then  multiply  it  by  0,08,  which  gives  0,024  c; 
whose  sum  is  s ^0,324  c.    This  method,  applied  to  the  preceding  examples  VII.,  VIII.,  produce  the   following  results: 


EXAMPLE     IX. 


Change  0",  6443o2  into  sexagesimals. 
0,3  c  =;  o*,  1932906 
Multiply  by  0,08  i5463248 

o',  208753848 


EXAMPLE     X  . 

Change  o",  076897  into  sexagesimals. 
0,3  c  =  o*,  0230691 
Multiply  by  0,08  1845528 

o*,  024914628 


TABLE  XI. 


To  convert  ccnte 

iiiiKil  degrees,  minutes,  and  seconds,  into 

^exagcsimals. 

1.— 

To  couvert 

coiUcàiinul  i 

ogrees  into  soxagesimals 

Cenic. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

i  m 

d  m 

d  m 

d  m 

d   ,11 

d  m 

d   m 

(l   m 

d   m 

d  m 

O 

0,00 

0,54 

1,48 

2,42 

3,36 

4,3o 

5,24 

6,18 

7,12 

8,06 

I 

y, 00 

9,54 

10,48 

11,42 

12,36 

i3,3o 

14,24 

i5,i8 

16,12 

17,06 

2 

18,00 

18,54 

19,48 

20,42 

2  1,36 

22,3o 

23,24 

24,18 

25,12 

26,06 

3 

27,00 

27,54 

28,48 

29,42 

3o,36 

3i,3o 

32,24 

33.18 

34,12 

35,06 

4 

36,oo 

36,54 

37,48 

38,42 

39,36 

4o,3o 

41,24 

42,18 

43,12 

44,06 

5 

45,00 

45,54 

46,48 

47,42 

48,36 

49,3o 

5o,24 

5i,i8 

52,12 

53,06 

6 

54,00 

54,54 

55,48 

56,42 

57,36 

58,3o 

59,24 

60,18 

61,12 

62,06 

7 

63,oo 

63,54 

64,48 

65,42 

66,36 

67,30 

68,24 

69,18 

70,12 

71,06 

8 

72,00 

72.54 

73,48 

74,42 

75,36 

76,30 

77,24 

78,18 

79,12 

80,06 

9 

81,00 

81,54 

82,48 

83,42 

84,36 

85, 3o 

86,24 

87,18 

88,12 

89,06 

10 

90,00 

90,54 

9', 48 

92,42 

93,36 

g4,3o 

95,24 

96,18 

97,12 

98,06 

1 1 

99>oo 

99-54 

100,48 

101,42 

102,36 

io3,3o 

104,24 

io5,i8 

106,12 

107,06 

l:> 

ioS,oo 

108,54 

109,48 

110,42 

111,36 

II2,3o 

ii3,24 

114,18 

Il5,12 

1  16,06 

l3 

117,00 

117,54 

118,48 

119,42 

120,36 

1 2 1 ,3o 

122,24 

123,18 

124,12 

125,06 

i4 

126,00 

126,54 

127,48 

128,42 

129,36 

i3o,3o 

i3i,24 

i32,i8 

i33,i2 

1 34,06 

i5 

i35,oo 

i35,54 

1 36,48 

1 37,42 

I 38,36 

I 39,30 

i4o,24 

i4i,i8 

142,12 

143,06 

i6 

1 44,00 

144,54 

1 45,48 

i46,42 

i47,36 

i48,3o 

149,24 

i5o,i8 

l5l,12 

1 52,06 

17 

1 53,00 

i53,54 

1 54,48 

i55,42 

1 56,36 

i57,3o 

1 58,24 

1 59,18 

160,12 

161,06 

iS 

162,00 

162,54 

i63,48 

164,42 

i65,36 

i66,3o 

167,24 

168,18 

169,12 

1 70,06 

■9 

171,00 

171,54 

172,48 

173,42 

174,36 

175,30 

176,24 

177,18 

178,12 

1  79,06 

20 

180,00 

180,54 

181,48 

182,42 

1 83,36 

i84,3o 

i85,24 

186,18 

187,12 

188,06 

21 

iSg,oo 

189,54 

190,48 

191,42 

192,36 

193,30 

194,24 

195,18 

196,12 

197,06 

22 

198,00 

198,54 

199,48 

200,42 

201,36 

202,3o 

2o3,24 

204,18 

2o5,12 

206,06 

23 

207,00 

207,54 

208,48 

209,42 

2io,36 

21  i,3o 

212,24 

2i3,i8 

2l4,i2 

21 5,06 

24 

216,00 

216,54 

217,48 

218,42 

2ig,36 

220, 3o 

221,24 

222,18 

223,12 

224,06 

25 

225,00 

225,54 

226,.'î8 

227,42 

228,36 

229,30 

23o,24 

23i,i8 

232,12 

233,06 

26 

234,00 

234,54 

235,48 

236,42 

237,36 

238,3o 

239,24 

240,18 

241,12 

242,06 

27 

243,00 

243,54 

244,48 

245,42 

246,36 

247,3o 

248,24 

249,18 

25o,I2 

25 1,06 

28 

252,00 

252,54 

253,48 

254,42 

255,36 

256,30 

257,24 

258,i8 

259,12 

260,06 

29 

261,00 

261,54 

262,48 

263,42 

264,36 

265,3o 

266,24 

267,18 

268,12 

269,06 

3o 

270,00 

270,54 

271,48 

272,42 

273,36 

274,30 

275,24 

276,18 

277,12 

278,06 

3i 

279,00 

279,54 

280,4s 

281,42 

282,36 

283,3o 

284,24 

285,18 

286,12 

287,06 

32 

288,00 

288,54 

289,48 

290,42 

291,36 

292,30 

293,24 

294,18 

295,12 

296,06 

33 

297,00 

297,54 

298,4s 

299,42 

3oo,36 

3oi,3o 

302,24 

3o3,i8 

3o4,i2 

3o5,o6 

34 

3o6,oo 

3o6,54 

307,48 

3o8,42 

3o9,36 

3io,3o 

3ll,24 

3i2,i8 

3i3,i2 

3 14,06 

35 

3 1 5,00 

3 I 5,54 

3i6,48 

317,42 

3 1 8,36 

3 19,30 

320,24 

321,18 

322,12 

323,06 

36 

324,00 

324,54 

325,48 

326,42 

327,36 

328,30 

329,24 

33o,i8 

33l,12 

332,06 

37 

333,00 

333,54 

334,48 

335,42 

336,36 

337,3o 

338,24 

339,18 

340,12 

341,06 

38 

342,00 

342,54 

343,48 

344,42 

345,36 

346,3o 

347,24 

348,18 

349,12 

35o,o6 

39 

35 1,00 

35 1,54 

352,48 

353,42 

354,36 

355, 3o 

356,24 

357,18 

358,12 

359,06 

II.  — T 

0   convert  c 

sntesiinal  ini 

notes  into  se 

^agesimals. 

Centet. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

m    s 

7n    5 

m    s 

m     s 

m    s 

ïft    s 

m    s 

m    s 

m    s 

m    s 

0 

0,00,0 

0,32,4 

1,04,8 

1,37,2 

2,09.6 

2,42,0 

3,i4,4 

3,46,8 

4,19,2 

4,5 1,6 

I 

5,24,0 

5,56,4 

6,28,8 

7,01,2 

7,33,6 

8,06,0 

8,38,4 

9,10,8 

9,43,2 

10,1 5,6 

2 

10,48,0 

11,20,4 

11,52,8 

12,25,2 

12,57,6 

i3,3o,o 

14,02,4 

1 4,34,8 

15,07,2 

15,39,6 

3 

16,12,0 

16,44,4 

17,16,8 

17,49,2 

18,21,6 

18,54,0 

19,26,4 

19,58,8 

20,3l,2 

2i,o3,6 

4 

21,36,0 

22,08,4 

22,40,8 

23,l3,2 

23,45,6 

24,18,0 

24,5o,4 

25,22,8 

25,55,2 

26,27,6 

5 

27,00,0 

27,32,4 

28,04,8 

28,37,2 

29,09,6 

29,42,0 

3o,i  4,4 

3o,46,8 

3i,i9,2 

3i,5i,6 

6 

32,24,0 

32,56,4 

33,28,8 

34,01,2 

34,33,6 

35,06,0 

35,38,4 

36, 10,8 

36,43,2 

37,1 5,6 

7 

37,48,0 

38,2o,4 

38,52,8 

39,25,2 

39,57,6 

4o,3o,o 

41,02,4 

41,34,8 

42,07,2 

42,39,6 

8 

43,12,0 

A^AM 

44,16,8 

44,49,2 

45,21,6 

45,54,0 

4C\-^<iÀ 

46,58,8 

47,5i,2 

48,o3,6 

9 

48,36,0 

49,08,4 

49,40,8 

5o,i3,2 

5o,45,6 

5 1,1 8,0 

5i,5o,4 

52,22,8 

52,55,2 

53,27,6 

m.— ï 

0  convert  c 

anteaimal  sec 

onds  into  so:; 

ageainmlâ. 

1 

Cînto. 
0 

0 

1 

2 

3 

4 

5 

s 
1,620 

6 

7 

8 

9 

s 

0,000 

s 

0,324 

0,648 

0,972 

s 

1,296 

1,944 

5 
2,268 

s 
2,592 

5 
2,916 

I 

3,240 

3,564 

3,888 

4,212 

4,536 

4,860 

5,184 

5,5o8 

5,832 

6,1 56 

2 

6,48o 

6,804 

7,128 

7,452 

7,776 

8,100 

8,424 

8,748 

9,072 

9,396 

3 

9,720 

10,044 

io,368 

10,692 

11,016 

1 1 ,340 

11,664 

11,988 

I2,3l2 

12,636 

4 

12,960 

i3,284 

1 3,608 

13,932 

i4,256 

i4,58o 

14,904 

l5,228 

i5,552 

15,876 

5 

16,200 

16,524 

i6,848 

17,172 

17,496 

17,820 

i8,i44 

18,468 

18,792 

19,116 

6 

19,440 

19,764 

20.088 

20,4 12 

20,736' 

21,060 

21,384 

2 1 ,708 

22,o32 

22,356 

7 

22,680 

23,004 

23,328 

23,652 

23,976 

24,3oo 

24,624 

24,948 

25,272 

25,596 

8 

25,920 

26,244 

26.568 

26,892 

27,216 

27,540 

27,864 

28,188 

28,512 

28,836 

9_ 

29,160 

29,484 

29,808 

3o,i32 

3o,456 

30.780 

3i,io4 

31,428 

3 1,752 

32,076 

a27 


TABLE  XII. 


To  convert  centesimal  seconds  into 

sexagesimr 

Is. 

Con(c>. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

Ccnic. 

5 

s 

S 

£ 

s 

5 

s 

s 

£ 

0 

s 

0,324 

o,648 

0,972 

1,296 

1,620 

1,944 

2,268 

2,592 

2,916 

0 

I 

3,240 

3,564 

3.888 

4,212 

4,536 

4,860 

5,184 

5,5o8 

5,832 

6,1 56 

I 

1 

6,480 

6,804 

7,128 

7.452 

7.776 

8,100 

8,424 

8,748 

9,072 

9,396 

3 

3 

9,720 

10,044 

10, 368 

10,693 

11,016 

1 1 ,340 

1 1 ,664 

11,988 

12,3 12 

12,636 

3 

4 

12, 960 

i3,284 

1 3,608 

13,932 

14,256 

i4,58o 

14,904 

15,228 

i5,552 

15,876 

4 

5 

16,200 

16,524 

16,848 

17,172 

17,496 

17,820 

i8,i44 

18,468 

18,792 

19,1 16 

5 

6 

19,440 

19,764 

20,088 

20,4 12 

20,736 

2 1 ,060 

21,384 

21,708 

22,o32 

2  2,356 

6 

7 

22,680 

23,oo4 

23,328 

23,652 

23,976 

24,3oo 

24,624 

24,948 

25,272 

25.596 

7 

8 

25,920 

26,244 

26,568 

26,892 

27,216 

27,540 

27,864 

28,188 

28,512 

28,836 

8 

9 

29,160 

29,484 

29,808 

3o,i32 

3o,456 

30,780 

3i,io4 

31,428 

3i,752 

32,076 

9 

10 

32,4oo 

32,724 

33,048 

33,372 

33,696 

34,020 

34,344 

34,668 

34,992 

35,3i6 

10 

II 

35,640 

35,964 

36,288 

36,6i2 

36,936 

37,260 

37,584 

37,908 

38,232 

38,556 

11 

12 

38,880 

39,204 

39,528 

39,852 

40,176 

4o,5oo 

40.824 

4i.i48 

4 1,472 

41,796 

12 

i3 

42,120 

42,444 

42,768 

43,092 

43,416 

43,740 

44,064 

44,388 

44,7  >  2 

45,o36 

i3 

i4 

45,36o 

45,684 

46,008 

46,332 

46,656 

46,980 

47.3o4 

47,628 

47,952 

48,276 

i4 

i5 

48,600 

48,924 

49,248 

49.572 

49,896 

5o,220 

5o,544 

5o,868 

51,192 

5i,5i6 

i5 

i6 

5 1,840 

52,164 

52,488 

52,812 

53,i36 

53,460 

53,784 

54,108 

54,432 

54,756 

16 

17 

55,080 

55,4o4 

55,728 

56,o52 

56,376 

56,700 

57,024 

57,348 

57,672 

57,996 

17 

i8 

58,320 

58,644 

58,g68 

59,292 

59,616 

59,940 

60,264 

6o,588 

6o,qi2 

6i,236 

18 

19 

6i,56o 

6 1,884 

62,208 

62,532 

62,856 

63,1 80 

63,5o4 

63,828 

64,1 52 

64,476 

19 

20 

64,800 

65,124 

65,448 

65,772 

66,096 

66,430 

66,744 

67,068 

67,392 

67,716 

20 

21 

68,o4o 

68,364 

68,688 

69,0 1 2 

69,336 

69,660 

69,984 

70,308 

70,632 

70,956 

21 

22 

71,280 

71,604 

71,928 

72,252 

72,576 

72,900 

73,224 

73,548 

73,872 

74,196 

22 

23 

74,520 

74.844 

75,168 

75,492 

75,816 

76,140 

76,464 

76,788 

77,112 

77,436 

23 

24 

77,760 

78,084 

78,408 

78,732 

79.056 

79,380 

79,704 

80,028 

80,352 

80,676 

24 

25 

8 1 ,000 

81,324 

81,648 

81.972 

82,296 

82,620 

82,944 

83,268 

83,5q2 

83,916 

25 

36 

84,240 

84,564 

84,888 

85,212 

85,536 

85,86o 

86,184 

86,5o8 

86,832 

87,1 56 

26 

27 

87,480 

87,804 

88,128 

88,452 

88,776 

89,100 

89,424 

89,748 

90,072 

90,396 

27 

28 

90,720 

91,044 

91,368 

91,692 

92,016 

92,340 

92,664 

92,988 

93,3i2 

93,636 

28 

29 

93,960 

94,284 

94,608 

94,932 

95,256 

95,580 

95,904 

96,228 

96,552 

96.876 

29 

3o 

97,200 

97,524 

97,848 

98,172 

98,496 

98,820 

99,144 

99,468 

99,792 

100,116 

3o 

3i 

100,440 

100,764 

1 0 1 ,088 

IOI,4l2 

101,786 

102,060 

102,384 

102,708 

io3,o32 

103,356 

3i 

32 

io3,68o 

io4,oo4 

104,328 

104,652 

104,976 

io5,3oo 

105,624 

105,948 

106,272 

106,596 

32 

33 

106,920 

107,244 

107,568 

107,892 

108,316 

108,540 

108,864 

109,188 

109,512 

109,836 

33 

34 

110,160 

110,484 

110,808 

111,132 

111,456 

111,780 

112,104 

112,428 

112,752 

113,076 

34 

35 

ii3,4oo 

113,724 

ii4,o48 

114,372 

114,696 

Il  5,020 

11 5,344 

Il  5,668 

115,992 

116,3 16 

35 

36 

ii6,64o 

1 1 6,964 

117,388 

117,612 

117,936 

118,260 

118,584 

118,908 

119,282 

119,556 

36 

37 

119,880 

120,204 

120,528 

120,852 

121,176 

12I,5oO 

121,824 

123, i48 

122,472 

123,796 

37 

38 

123,120 

123,444 

123,768 

124,092 

124,416 

124,740 

125,064 

125,388 

125,712 

i26,o36 

38 

39 

126,360 

126,684 

127,008 

127,332 

127,656 

127,980 

128,304 

128,628 

128,952 

129,276 

39 

40 

129,600 

129,924 

i3o,248 

1 30,572 

130,896 

l3l,220 

1 3 1,544 

1 3 1,868 

133,192 

i32,5i6 

40 

4i 

1 3  2,840 

i33,i64 

I 33,488 

i33,8i2 

1 34,1 36 

1 34,460 

134,784 

i35,io8 

i35,432 

135,756 

41 

42 

i36,o8o 

i36,4o4 

1 36,728 

i37,o52 

137,376 

137,700 

i38,o24 

138,348 

138,672 

1 38,996 

42 

43 

139,320 

139,644 

139,968 

140,292 

1 40,61 6 

1 40,940 

141,264 

i4i,588 

141,912 

i42,236 

43 

44 

i42,56o 

142,884 

143,208 

143,532 

143,856 

144,180 

i44,5o4 

144,828 

i45,i52 

145,476 

44 

45 

145,800 

i46>i24 

146,448 

146,772 

147.096 

147.420 

147,744 

148,068 

148,392 

148,716 

45 

46 

1 49,040 

149,364 

149,688 

l5o,012 

i5o,336 

1 5o,66o 

1 50,984 

i5i,3o8 

1 5 1,632 

1 5 1.966 

46 

47 

152,280 

i52,6o4 

152,928 

i53,252 

153,576 

153,900 

i54,224 

154,548 

154,872 

155,196 

47 

48 

i55,52o 

155,844 

i56,i68 

1 56,492 

1 56,8 16 

i5-7,r4o 

157,464 

157.788 

i58,ii2 

158,436 

48 

49 

158,760 

159,084 

159,408 

159,732 

i6o,o56 

160,380 

160,704 

161,028 

161,352 

161,676 

49 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

TABLE    XII. 


Ti 

convert  centesimal  seconds  into  sexagesima 

s. 

Centei. 

0 

1 

2 

3 

4 

5 

6 

7 

8 

9 

Cemci. 

5o 

5 
162,000 

s 

162,324 

162,648 

s 
162,972 

163,296 

s 

163,620 

163,944 

164,268 

5 
164,592 

164,916 

^0 

5i 

i65,24o 

165,564 

i65,888 

1(56,212 

166,536 

166,860 

167,184 

167,508 

167,832 

168,1 56 

5i 

52 

168,480 

168,804 

169,128 

169,452 

169,776 

170,100 

170,424 

170,748 

171,072 

171,396 

52 

53 

171,720 

172,044 

172,368 

172,692 

173,016 

173,340 

173,664 

173,988 

174,312 

174,636 

53 

54 

174,960 

175,284 

175,608 

175,932 

176,256 

176,580 

176,904 

177,228 

177,552 

177,876 

54 

55 

178,200 

178,524 

178,848 

179,172 

179.496 

179,820 

180,144 

180,468 

180,792 

181,116 

55 

56 

181,440 

181,764 

182,088 

182,412 

182,736 

1 83, 060 

183,384 

183,708 

i84,o32 

I 84,356 

56 

57 

184,680 

i85,oo4 

185,328 

185,652 

185,976 

i86,3oo 

186,624 

186,948 

187,272 

187,596 

57 

58 

187,920 

188,244 

188,568 

188,892 

189,216 

189,540 

189,864 

190,188 

190,512 

1  go  ,836 

58 

59 

191,160 

191,484 

191,808 

192,132 

192,456 

192,780 

193,104 

193,428 

193,752 

194,076 

59 

6o 

194,400 

194,724 

195,048 

195,372 

195,696 

196,020 

196,344 

196,668 

196,992 

197,316 

60 

6i 

197,640 

197,964 

198,288 

198,612 

198,936 

199,260 

199,584 

199,908 

200,232 

200,556 

61 

62 

200,880 

201,204 

201,528 

201,852 

202,176 

202,5oO 

202,824 

2o3,i48 

203,472 

203,796 

62 

63 

204,120 

204,444 

204,768 

205,092 

2o5,4i6 

2o5,74o 

206,064 

206,388 

206,712 

207,036 

63 

64 

207,360 

207.684 

208,008 

208,332 

2o8,656 

208,980 

209,304 

209,628 

209,952 

210,276 

64 

65 

210,600 

210,924 

211,248 

211,572 

2 1 1 ,896 

212,220 

212,544 

212,868 

213,192 

2i3,5i6 

65 

66 

2i3,84o 

2i4,i64 

214,488 

214,812 

2i5,i36 

21  5,460 

215,784 

216,108 

216,432 

3i6,756 

66 

67 

217,080 

217,404 

217,728 

2l8,o52 

218,376 

218,700 

219,024 

219,348 

219,672 

219,996 

67 

68 

220,320 

220,644 

220,968 

221,292 

221,616 

221,940 

222,264 

222,588 

222,912 

223,236 

68 

69 

2  23,56o 

223,884 

224,208 

224,532 

224,856 

225,180 

225,5o4 

225,828 

226,152 

226,476 

69 

70 

226,800 

227,124 

227,448 

227,772 

228,096 

228,420 

228,744 

229,068 

229,392 

229,716 

70 

71 

23o,o4o 

230,364 

23o,688 

23l,OI2 

231,336 

23 1,660 

231,984 

232, 3o8 

232,632 

232,956 

71 

72 

233,280 

233,604 

233,928 

234,252 

234,576 

234,900 

235,224 

235,548 

235,872 

236,196 

72 

73 

236,520 

236,844 

237,168 

237,492 

237,816 

238, i4o 

238,464 

238,788 

239,112 

239,436 

73 

74 

239,760 

240,084 

240,408 

240,732 

24 1  ,o56 

241, 38o 

241,704 

242,028 

242,352 

242,676 

74 

75 

243,000 

243,324 

243,648 

243,972 

244,396 

244,620 

244,944 

245,268 

245,592 

245,916 

75 

76 

246,240 

246,564 

246,888 

247,212 

247,536 

247,860 

248,184 

248,5o8 

248,832 

349,1 56 

76 

77 

249,480 

249,804 

25o,I2S 

25o,452 

250,776 

25l,IOO 

25i,424 

25i,748 

252,072 

252,396 

77 

78 

252,720 

253,044 

253,368 

253,692 

254,016 

254,340 

254,664 

254,988 

255,3i2 

255,636 

78 

79 

255,960 

256,284 

256,6q8 

256,932 

257,256 

257,580 

257,904 

258,228 

258,552 

258,876 

79 

80 

239,200 

259,524 

259,848 

260,172 

260,496 

260,820 

261,144 

261,468 

261,792 

262,116 

80 

81 

262,440 

262,764 

263,088 

263,412 

263,736 

264,060 

264,384 

264,708 

265,032 

265,356 

81 

82 

265,680 

266,004 

266,328 

266,652 

266,976 

267,300 

267,624 

267,948 

268,272 

268,596 

82 

83 

268,920 

269,244 

269,568 

269,892 

270,216 

270,540 

270,864 

271,188 

271,512 

271,836 

83 

84 

272,160 

272,484 

272,808 

273,132 

273,456 

273,780 

274,104 

274,428 

274,752 

275,076 

84 

85 

275,400 

275,724 

276,048 

276,372 

276,696 

277,020 

277,344 

277,668 

277,992 

278,316 

85 

86 

278,640 

278,964 

279,288 

279,612 

279,936 

280,260 

280,584 

280,908 

281,232 

281,556 

86 

87 

281,880 

282,204 

282,528 

282,852 

383,176 

283,5oo 

283,824 

284,148 

284,472 

284,796 

87 

88 

285,120 

285,444 

185,768 

286,092 

286,416 

286,740 

287,064 

287,388 

287,712 

288,036 

88 

89 

288,360 

288,684 

289,008 

289,332 

289,656 

289,980 

290,304 

290,628 

290,952 

291,276 

89 

90 

291,600 

291,924 

292,248 

292,572 

292,896 

293,220 

293,544 

293,868 

294,192 

294,516 

90 

91 

294,840 

295,164 

295,488 

295,812 

296,136 

296,460 

296,784 

297,108 

297,432 

297,756 

91 

92 

298,080 

298,404 

298,728 

299,052 

299,376 

299,700 

3oo,o24 

3oo,348 

300,672 

300,996 

92 

93 

3oi,32o 

3oi,644 

301,968 

302,292 

3o2,6i6 

3o2,94o 

303,264 

3o3,588 

303,912 

3o4,236 

93 

94 

3o4,56o 

3o4,884 

3o5,2o8 

3o5,532 

3o5,856 

3o6,i8o 

3o6,5o4 

306,828 

3o7,i52 

307,476 

94 

95 

307,800 

3o8,i24 

3o8,448 

308,772 

309,096 

309,420 

309,744 

3 10,068 

310,392 

3io,7i6 

95 

96 

3 1 1  ,o4o 

3 11,364 

3 11,688 

3l2,012 

312,336 

3 12,660 

312,984 

3i3,3o8 

3i  3,632 

3i3,956 

96 

97 

3 14,280 

3i4,6o4 

314,928 

3i5,252 

315,576 

3 15,900 

3i6.234 

3 16.548 

316,872 

317,196 

97 

98 

3i7,520 

317,844 

3i8,i68 

318,492 

3iS,8i6 

319, i4o 

3 19,464 

319,788 

320,112 

320,436 

98 

99 

320,760 

321,084 

321,408 

321,732 
3 

322,o56 

322,38o 

322,704 

323,028 

323,352 

323,676 

99 

0 

1 

2 

4 

5 

6 

7 

8 

9 

,,^„^;-,;^, 


AUTHOR 

La  Place. 


TITLE 


351 
L32 


cXt^^^-^ 


31037 


Astron 

qQB 
351 
L32 


3 

31037 


\  ••t*-^.v   -  .■     H*  •to  ■         . 


Jf#Vi