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RUDIMENTARY 

DICTIONARY    OF    TERMS 

USED   IN 

ARCHITECTURE,  CIVIL, 

ARCHITECTURE,   NAVAL, 

BUILDING  AND  CONSTRUCTION, 

EARLY  AND  ECCLESLA.STICAL  ART, 

ENGINEERING,  CIVIL, 

ENGINEERING,  MECHANICAL, 

FINE  ART, 

MINING,  SURVEYING,  ETC. 


L\>'    ^> 


TO  WDICn   ABB  ADDED 

EXPLANATORY    OBSERV ATIONifS- 


ON-  f\-  -■  .    '         ,'*• 


NUSiBROUS    SUBJECTS    CONNECTED  WITH    PRACTICAL   ART  4nD,  SlCIEN^.*^ 


BY  JOHN  WEALE, 

AVTHOB  OP 

A  Treatise  entitled  *  Divers  Works  of  Early  Masters  in  Christian  Decoration,  with 
Examples  of  Ecclesiastical  Ornament,  Ancient  Painted  and  Stained  Glass,* 

in  two  folio  volumes ; 

AMD   EDITOR  OP 

*  Ensamples  of  Railway  Making  ;* 

'  Papers  on  Architecture,'  in  four  volumes  quarto ;  and 

*  Papers  on  Engineering,'  in  six  volumes  quarto. 


JOHN   WEALE,   59,   HIGH   HOLBORN. 

1849~5«. 


BV(>BB8  Al«D  ItOBlHSON,   PBIRTBBS, 
BIMG'S     BBAD     COUBT,    eOUGB    SaUABB. 


PREFACE. 

It  was  intended  that  the  contents  of  this  work  should  be 
comprised  within  the  space  of  about  one  hundred  and  fifty 
pages,  and  thus  form  a  single  Tolume  of  the  series  of  *  Kudi- 
mentary  Treatises;'  but  in  the  course  of  its  compilation 
it  soon  became  apparent  that  such  confined  Umits  were 
wholly  inadequate  to  the  admission  of  explanations  of  terms, 
which,  although  not  immediately  connected  with  the  sub- 
jects mentioned  in  the  title-page,  were  yet  deemed  essential 
to  their  further  amplification:  its  utiHty  as  a  book  of  re- 
ference win  therefore,  it  is  hoped,  be  found  commensurate 
with  its  necessarily  increased  extent. 

Since  the  publication,  in  1819,  of  Mr.  Peter  Nicholson's 
elaborate  ^Architectural  Dictionary,'  in  two  quarto  Tolumes, 
changes  of  vast  import  have  occurred :  the  field  of  practical 
science  has  been  widely  extended,  and  proportionately  occupied 
by  a  new  generation  of  professional  men  and  students ;  im- 
portant advances  have  been  made  in  the  arts  of  design  and 
construction ;  and  the  extended  appHcation  of  steam  as  a 
motive  power  has  not  only  produced  an  extraordinary  de- 
velopment of  the  means  of  internal  communication,  but 
surmounted  those  impediments  which  considerations  of  space 
and  time  formerly  presented  to  the  pursuits  of  men  in  quest 
of  business  or  pleasure, — ^thus  influencing,  to  a  great  extent, 
the  various  operations  by  which  the  wants  and  luxuries  of 
civilized  life  are  supplied. 

In  a  ratio  proportionate  to  the  rapid  extension  of  what 

a3 


Tl  PREFACE. 


may  be  strictly  termed  practical  knowledge  has  the  study  of 
the  more  pleasurable  sciences  also  progressed:  archaeology, 
geology^  philosophy,  &c.,  have  exercised  a  powerful  and  cap- 
tivating influence,  which  has  gradually  led  to  the  incorporation 
of  societies  or  associations  devoted  to  the  cultivation  and 
advancement  of  the  several  branches  of  human  knowledge ; 
and  hence  has  arisen  an  extensive  class  of  non-professional 
men,  who,  however  duly  acquainted  with  scientific  principles, 
may  yet  be  anxious  to  possess  any  easily  available  means 
of  becoming  familiar  with  the  nomenclature  and  the  technical 
language  necessarily  employed  in  a  series  of  rudimentary 
treatises  on  the  practical  arts  and  sciences. 

Within  the  period  already  adverted  to,  much  professional 
taste  and  skill  has  been  displayed  in  the  erection  of  public 
buildings,  in  the  construction  of  engineering  works  of  vast 
magnitude  and  importance,  and  in  the  invention  of  the  im- 
proved machinery  employed  in  the  arts  and  manufactures 
of  the  country.  These  and  similar  causes  have  combined 
greatly  to  augment  the  ranks  of  a  meritorious  and  useful 
class  of  men,  among  whom,  more  especially,  new  wants  may 
be  said  to  have  been  created,  —  a  dass  which  comprises  no 
inconsiderable  number  of  ingenious  operative  engineers  and 
matured  artisans ;  and  to  such  this  work  may  become  in- 
teresting and  useful,  however  insuflSicient  it  may  prove  to 
those  already  advanced  in  their  professional  pursuits. 

Should,  however,  the  paucity  of  information  contained  in 
the  following  pages  induce  others  more  competent  to  the 
task,  and  who  have  sufficient  leisure  for  the  purpose,  to 
devote  their  talents  and  time  to  the  production  of  a  more 
comprehensive  and  more  valuable  compilation,  some  share  of 
useful  information  will  at  least  have  been  contributed  to  the 
means  of  supplying  the  wants  of  an  improving  age. 

The  slender  efforts  here  placed  before  the  reader  were 


PRKFACB.  TU 


aocomplished*  by  the  aid  of  the  lamp,  after  the  honn  uauall j 
deroted  to  the  labours  of  business,  and  they  are  now,  with 
the  most  humble  pretensions,  submitted  to  public  approval. 
It  has  been  well  observed,  that  'the  kngnage  of  truth  is 
simple :'  no  attempt  has  here  been  made  to  trace  the  deriva- 
tions of  the  scientific  or  technical  terms  which  have  been 
adopted:  they  are  given  and  explained  as  generally  writtoi 
and  understood  at  the  present  period,  and  care  has  been 
taken  to  avoid  surreptitious  or  unauthorized  versions,  with 
the  view  of  guiding  the  student  and  the  operative  workman 
in  the  onward  path  of  knowledge. 

Some  analogous  explanations  and  references  may  probably 
appear,  at  a  first  glance,  as  superfluous,  and  to  detract  from 
the  merits  of  the  work;  but  when  it  is  considered  how 
numerous  and  varied,  in  the  present  age,  are  the  ramifications 
into  which  the  employment  of  those  engaged  in  the  building 
and  constructive  arts  has  been  extended,  and  how  earnestly 
the  searchers  after  technical  terms  and  meanings  must  desire 
the  acquisition  of  a  knowledge  of  what  may  not  inaptly  be 
designated  as  a  correct  disposition  of  fine  art,  any  unfavour- 
able impression  of  this  nature,  hastily  formed,  will  probably 
be  removed  upon  mature  reflection. 

The  collation  made  firom  Dugdale's  '  Monaaticon,'  of  the 
abbeys,  alien  priories,  collegiate  churches,  monasteries,  &c., 
with  their  several  orders,  dates  of  foundation,  and  localities, 
may  perhaps  be  looked  on  with  indifference  by  the  mechanical 
engineer,  as  embracing  subjects  of  little  or  no  importance ; 
bnt  viewed  archseologically,  by  the  architect,  the  historian, 
or  the  antiquary,  a  reference  to  researches  into  the  early 
architecture  of  his  country  must  ever  command  a  paramount 
degree  of  interest.  Similarly,  with  the  latter  class,  objections 
niay  be  raised  vrith  regard  to  subjects  merely  mechanical; 
and  it  is  therefore  earnestly  to  be  desired  that  each  may  be 


TIU  PREFACE. 


disposed  to  indulge  the  predilections  of  the  other  as  to  their 
more  favoared  pursuits. 

In  referring  to  the  series  of  *  Rudimentary  Scientific 
"Works'  to  which  this  'Dictionary  of  Terms*  will,  it  is  pre- 
sumed, he  deemed  an  appropriate  Companion,  it  is  proper 
to  mention  that  the  first  suggestion  as  to  their  publication 
emanated  from  Lieutenant -Colonel  Reid,  of  the  Corps  of 
Royal  Engineers,  who,  during  his  residence  at  Barbadoes  as 
Her  Majesty's  representative,  kindly  forwarded  to  the  Pub- 
lisher, with  a  recommendation  that  it  should  be  printed  for 
general  circulation,  a  copy  of  Professor  Fownes's  *  Rudimen- 
tary Chemistry.'  This  elementary  treatise,  the  first  of  the 
series,  and  to  which  the  recommendation  of  the  late  Go- 
vernor of  Barbadoes  was  Umited,  had  been  printed  at  hid  own 
expense,  for  the  laudable  and  special  purpose  of  adding  to 
the  numerous  educational  and  scientific  works  which  he  had 
already  distributed  among  different  classes  in  the  West  India 
colonies. 

To  Lieut.-Colonel  Portlock,  R.  E., — ^to  the  Commissioners 
of  Northern  Lighthouses,  and  to  others  who  have  hberally 
contributed  their  assistance  in  the  production  of  the  suc- 
ceeding tfeatises,  the  PubHsher  thus  acknowledges  his 
obligations;  and  as  the  series  has  been  extended  to  thirty 
volumes,  the  public  have  now  the  means  of  forming  a  due 
estimate  of  their  efficacy  and  utility,  and  of  the  discretion 
exercised  in  the  selection  of  subjects. 

J.W. 

59,  High  Holbom, 
November  1, 1849. 


UST  OF  THE  WORKS  WHICH  HAVE  BEEN  CONSULTED  IN 
THE   COMPILATION  OF  THIS  DICTIONARY. 


Adooek's  Rules  and  Data  fbr  the  Steam  Engine,  &e.  12mo.  1839. 
Aide-M&noire  to  the  Military  Sciences,  Parts  I.  II.  III.  1845-8. 
Britten's  Aichitectural  Dictionary.  4to.  1838. 
Brown's  Prindplea  of  Perspective.  4to.  1835. 
Bacfaanan's  Technological  Dictionary.  12mo.  1849. 

Practical  Essays  on  Mill-work  and  on  Machinery  and  Tools. 

2  vols.  8to.  :  edited  by  George  Rennie,  1841. 
Builder's  (the)  Dictionary.  2  yols.  4to.  1788. 
Bnry's  Styles  of  Architecture.  12mo.  1849. 
Cslmet's  Dictionary  of  the  Bible.  8vo.  1848. 
CsmpbeU's  Text-Book  of  Inorganic  Chemistry.  12mo.  1849. 
Csstell's  Villas  of  the  Ancients.  foL  1728. 
Clegg's  Essay  on  the  Architecture  of  Machinery.  4to.  1842. 

-—  Manuftcture  and  Distribution  of  Coal  Gas.  4to.  1840. 

Dana's  Seaman's  Vade  Mecum.  12mo.  1849. 

Dempsey's  Practical  Railway  Engineer.  4to.  1847. 

Dictionary  of  Painters,  Sculptors,  and  Engravers.  8vo.  1810. 

Dodd's  (Ralph)  Observations  on  Water.  18mo.  1805. 

Dugdale's  Monasticon  Anglicannm.  8  vols,  folio :  now  in  course  of  repub* 
lication  in  guinea  parts. 

Eosamples  of  Railway  Making.  8vo.  1843. 

Ewbank's  Hydraulics  and  Machinery.  8vo.  New  York,  1849. 

Fergusson's  Rock-Cut  Temples  of  India:  plates  folio,  text  8vo.  1845. 

HeUl's  Chromatognq^hy.  8vo.  1841. 

Gsidner's  Railway  Mensuration :  imperial  8vo:  1848. 

Glossary  of  Architecture.  2  vols.  Oxford,  Parker.  1845. 

Greir's  Mechanical  Dictionary.  12mo.  1847. 

Gregory's  Mathematics  for  Practical  Men,  by  Henry  Uw ;  Isrge  8vo.  1848. 


LIST   OF   WORKS   CONSULTED. 


Gwilt's  (Joseph)  Encydopsedia  of  Architecture.  8vo.  1847. 

■     edition  of  Sir  William  Chamhers's  Civil  Architecture. 

2  vols,  imperial  8vo.  1824. 
Notitia  Architectonica  Italiano.  8vo.  1818. 


Hamilton  on  Terms  used  in  the  Arts  and  Sciences.  12mo.  1825. 
Hann's  Theoretical  and  Practical  Mechanics.  8vo.  1849. 
Hann's,  &c.  Theory  and  Practice  of  Bridges.  4  vols,  in  3 :  large*  8vo.  1843. 
HolzapffeFs  Turnery  and  Mechanical  Manipulation.  2  vols.  8vo.  1846-7. 
Homersham  on  Water  Supply  to  Manchester  and  the  adjacent  Tovms. 

8vo.  1849. 
Hunt's  Tudor  Architecture.  4to.  1830. 

Hutton's  Mathematical  and  Philosophical  Dictionary.  2  vols.  4to.  1815. 
Jamieson's  (Dr.)  Dictionary  of  Mechanical  Science.  4to.  1827. 

— Mechanics  for  Practical  Men.  8vo.  1830. 

Leeds's  Preface  to  Lamb's  Studies :  imperial  4to. 

Leeds's  Rudimentary  Treatise  on  the  Orders  of  Architecture.  12mo.  1849. 

Meason's  Architecture  of  the  Great  Painters  of  Italy.  4to.  1828. 

Meteorological  Society's  Transactions,  vol.  i.  large  8vo.  1839. 

National  Encyclopaedia,  now  in  course  of  publication  by  Mr.  Charles 

Knight,  in  monthly  parts. 
Nicholson's  Architectural  Dictionary.  2  vols.  4to.  1819. 

Mechanical  Exercises.  8vo.  1819. 

Normand's  Parallel  of  the  Orders  of  Architecture,  by  Pugin  :  folio.  1829. 
Palladio's  Architecture,  with  Notes  by  Inigo  Jones.  2  vols,  folio.  1742. 
Pambour's  Practical  Treatise  on  Locomotive  Engines.  8vo.  1840. 
Papers  connected  with  the  Duties  of  the  Corps  of  Royal  Engineers.  10  vols. 

:»        4to.  1835-1849. 
Pole  on  the  Ck>mish  Pumping  Engine.  1  vol.  4to.  folio  plates.  1844. 
Pryce's  Treatise  on  Mines  and  Minerals,  folio.  1773. 
Pugin's  True  Principles  of  Pointed  or  Christian  Architecture.  4to.  1841. 
Apology  for  the  Revival  of  Christian  Architecture  in  Enghind. 

4to.  1843. 
Reid  (Lieut.-Col.)  on  the  Law  of  Storms :  large  8vo.  1842. 
Repton's  Theory  and  Practice  of  Landscape  Architecture :  large  4to.  1805. 
Rich's  Companion  to  the  Greek  Lexicon  and  Latin  Dictionary.  8Vo.  1849. 
Smith's  Classical  Dictionary :  large  8vo.  1849. 
Stalkartt's  Naval  Architecture.  2  vols,  folio.  1803. 
Stephenson's  (Robert)  Report  on  the  Atmospheric  Railway  System.  4to. 

1844. 
Stuart's  Antiquities  of  Athens,  vols.  ii.  &  m.  folio :  last  edition.  1825. 
Thorman's  Taunus  Railway.  4to.  1846. 
Tomlinson's  Rudimentary  Natural  Philosophy.  12mo.  1848. 


LIST   OF  WORKS   CONSULTED.  XI 

Transactions  of  the  Institutioii  of  Civil  Engineers.  3  vols.  4lo.  1835-40. 

Tredgold  on  the  Steam  Engme.  2  vols.  4to.  1838-1849. 

Tredgold  on  the  Strength  of  Cast  Iron.  Svo.  1842. 

Tredgold's  Elementary  Principles  of  Carpentry.  4to.  1840. 

Vicat  on  Cements,  by  Capt.  Smith.  8vo.  1837. 

Vitroyins's  Civil  Architecture,  by  Wilkins :  imperial  4to.  1812. 

Wathen's  Arts,  Antiquities,  and  Chronology  of  Ancient  Egypt :  large  8vo. 

1843. 
Watson's  Account  of  Mines.  Svo.  1843. 
Wigbtwick's  Hints  to  Yoong  Architects.  8vo.  1846. 
Willis's  (Professor)  Architectural  Nomenclature.  4to.  Cambridge. 
Wood's  Letters  of  an  Architect  from  France,  Italy,  and  Greece.  2  vols. 

4to.  1828. 


J 


NOTICE. 

The  two  Farts  of  the  work  now  published^  it  will  be  per- 
ceiyed,  extend  only  to  the  letter  Mi  the  remaining  portion 
is  now  in  the  press,  and  will  probably  be  ready  for  publi- 
cation by  the  end  of  the  present  year ;  but  as  various  works 
have  necessarily  to  be  consulted  for  correct  definitions  and 
explanations,  the  time  required  for  its  completion  will  not, 
it  is  presumed,  be  deemed  unreasonable. 

*^*  For  each  Fart,  comprising  six  sheets,  or  144  pinges.  Is,  is 
charged;  or  for  the  two  Farts,  bound  together,  and  con- 
tainmg  12  sheets,  or  288  pages,  2«. 


DICTIONARY  OF  TERMS 


USED 


IN  ARCHITECTURE,  BUILDING,  ENGINEERING, 


NAVAL  ARCHITECTURE,  ARCHJEOLOGY,  &c. 


ABA 


ABBEYS. 


ABB 


Aaron's-rod,  an  ornamental  figure 

representing  a  rod  with  a  serpent 

entwined    about    it;     improperly 

calfed  the  caduceug  of  Mercury 

AbacUcuSy  small  tesserse  or  square 

stones  for  tesselated  paTement 
Abacotf  the  cap  of  state,  a  double 
crown  formerly  worn  by  the  sove- 
reigns of  England 
Abacubis,  a  small  table  or  desk 
AbactUf  a  small  tile  or  covering  mem- 
ber of   a  capital,  varying  in  the 
several  orders :  in  Grecian  Doric, 
square,  without  chamfer  or  mould- 
ing ;  in  Roman  Doric  it  has  an  ogee 
or  fillet  round  the  upper  edges ;  in 
the  Tuscan,  a  plain  fillet  and  a  ca- 
vetto  under  it ;  in  Grecian  Ionic  it 
is  thinner,  with  ovolo  only ;  in  Ro- 
man Ionic,  an  ogee  and  ovolo,  and 
fillet  above ;  in  the  Saxon  and  Nor- 
man styles,  and  in  early  Enghsh,  it 
varies  in  form  and  substance, — flat, 
chamfered,  and  hollow,  circular  and 
octagonal,  with  mouldings,  latterly 
decorated 
Abacus  fiui;or,alarge  trough  towashin 
Abaft,  towards  the  stem  of  a  ship 
Abaigedf  in  heraldry,  a  term  applied 


to  the  wings  of  eagles  when  the 
tips  are  depressed  below  the  centre 
of  the  shield 

jibaiseTf  burnt  ivory,  ior  ivory  black 

jibamurus,  a  buttress  or  second  wall, 
added  to  strengthen  another 

Abatement,  in  heraldry,  a  figure  in  a 
coat  of  arms  expressing  stain  or 
dishonour 

Abat-jour,  a  skyKght,  or  aperture  for 
the  admission  of  light 

Abattoir,  a  building  appropriated  to 
the  slaughtering  of  cattle 

Abat-vent,  the  sloping  roof  of  a  tower; 
a  pent-house 

Abat'Voix,  the  sounding  board  over  a 
pulpit  or  rostrum 

Abbey,  a  building  annexed  to  or  ad- 
jacent to  a  convent  or  monastery, 
for  the  residence  of  the  abbot  or 
abbess,  and  the  whole  combining  a 
series  of  buildings  for  the  accommo- 
dation of  a  fraternity  under  ecclesi- 
astical government 

Abbeys  in  Great  Britain  and  Ireland, 
alphabetically  arranged,  with  their 
respective  orders,  the  dates  of  their 
foundation,  and  their  several  locali- 
ties : 


NAME. 

Abbotsbury 
Aberbrothic 
Abingdon     . 
Alcester  .     • 
Alnwick . 


ORDER. 

Benedictine 
Tyrone 

Benedictine 
Do. 

Premonstrant 


DATE. 

drca  1026 

1178 
ante  955 

1140 

1147 


COUNTY. 

Dorsetshire 

Forfarshire 

Berkshire 

Warwickshire 

Northumberland 


ABB 

ABBEYS. 

ABB 

NAME. 

ORDER. 

DATE. 

COUNTY. 

Appleby 

White  Monks 

1281 

Westmoreland 

Athelney     .... 

Benedictine 

circa  888 

Somersetshire 

Austin 

Augustine 

1005 

Do. 

Balmerinoch     .     .    . 

Cistercian 

1229 

Fifeshire 

Ballintobber     .    .    . 

Augustine 

1216 

Mayo 

Bardney 

Benedictine 

temp.  W.  Con. 

Lincolnshire 

Bardsey  Island      .    . 

Black  Friars 

1276 

Caernarvonshire 

Barling 

Premonstrant 

1154 

Lincolnshire 

Ba8ing;work.    .    .    . 

Cistercian 

1159 

Flintshire 

Battle 

Benedictine 

1067 

Sussex 

Bayham 

Premonstrant 

1200 

Do. 

Beauchief    .... 

Do. 

1183 

Derbyshire 

Beanlieu 

Cistercian 

1204 

Hampshire 

Bermondsey     .    .    . 

Do. 

1082 

Surrey 

Bileigh 

Premonstrant 

1180 

Essex 

Bindon 

Cistercian 

1172 

Dorsetshire 

Bisham 

Augustine 

1338 

Berkshire 

Bittlesden    .... 

Cistercian 

1147 

Buckinghamshire 

Blanchland  .... 

Premonstrant 

1165 

Northumberland 

Bbinchland  •  ,  •    .    . 

Cistercian 

1143 

Carmarthenshire 

Bordesley    .... 

Do. 

1138 

Worcestershire 

Bourn 

Augustine 

1138 

Lincolnshire 

Boxley 

Cistercian 

1146 

Kent 

Brueme 

Do. 

1147 

Oxfordshire 

Buckfastleigh   .    .    . 

Do. 

1137 

Devonshire 

Buckland     .... 

Do. 

1278 

Do. 

Builderwas  .... 

Do. 

1135 

Shropshire 

Burnham     .... 

Augustine 

1255 

Buckinghamshire 

Burton  on  Trent   .    . 

Benedictine 

1004 

Staffordshire 

Bury  St.  Edmund's    . 

Do. 

1020 

Suffolk 

Byland 

Cistercian 

1177 

Yorkshire 

Caerleon 

Do. 

1227 

Monmouthshire 

Calder 

Do. 

1134 

Cumberland 

Calke 

Augustine 

1161 

Derbyshire 

Cambus  Kenneth  .    . 

Do. 

1147 

Clackmannanshire 

Cemi 

Benedictine 

1172 

Dorsetshire 

Chertsey      .... 

Do. 

temp.  Edgar 

Surrey 

Chrehe 

Augustine 

1118  , 

Essex 

Cirencester  .... 

Do. 

1117 

Gloucestershire 

Clyve 

Cistercian 

1188 

Somersetshire 

Coggeshall  .... 

Do. 

1142 

Essex 

Cokersand   .... 

Premonstrant 

1190 

Lancashire 

Colchester   .... 

Benedictine 

1142 

Essex 

Colunsay      .... 

Augustine 

1230 

Argyleshire 

Combe 

Cistercian 

1150 

Warwickshire 

Combermere     .    .    . 

Do. 

1133 

Cheshire 

Conway 

Do. 

1185 

Caernarvonshire 

Coupar    

Do. 

1164 

Forfarshire 

Covcrsham  .... 

Premonstrant 

14  John 

Yorkshire 

Cranbum     .... 

Benedictine 

980 

Dorsetshire 

Creyk 

Augustine 

1206 

Norfolk 

Crossraguel .... 

Cluniac 

1244 

Ayrshire 

Croxden  .    .     .^.     . 

Cistercian 

1176 

Staffordshire 

ABB                                                  ABBEYS. 

ABB 

NAME. 

ORDER. 

DATE. 

COUNTY. 

Croxton 

Premonstrant 

1162 

Leicestershire 

Croyland      .     . 

Benedictine 

948 

Lincolnshire 

Cnlros      .     .     . 

Cistercian 

1217 

Perthshire 

Cumhyre      •     . 

Do. 

1143 

Radnorshire 

Dale,  le  •     •     . 

Premonstrant 

temp.  Hen.II. 

Derbyshire 

Deer  .     •     -     . 

Cistercian 

1218 

Aberdeenshire 

De  la  Pre     .     . 

Cluniac 

temp.  Steph. 

Northamptonshire 

Denny     .     .     . 

Benedictine 

980 

Cambridgeshire 

Derley     .     .     . 

Augustine 

temp.  Hen.  I. 

Derbyshire 

Dieulacres    .     . 

Cistercian 

1214 

Staffordshire 

Dorchester  .     . 

Augustine 

1140 

Oxfordshire 

Dore  .... 

Cistercian 

temp.  Steph. 

Herefordshire 

Downpatrick     . 

Benedictine 

493 

Down 

Drybnrgh      .     • 

Premonstrant 

1152 

Roxburghshire 

Dnisk      •     •     • 

Cistercian 

1212 

Kilkenny 

Dumfermling    . 

Benedictine 

1124 

Fifeshire 

Danbrody     •     - 

Cistercian 

1178 

Wexford 

Dundrenan 

Do. 

1142 

Kirkcudbright 

Dunkeswell  •     • 

Do. 

1201 

Devonshire 

Dareford      .     • 

Premonstrant 

1169 

SuSSflK 

Egliston  .     • 

Do. 

temp.  Ric.  I. 

Yorkshire 

Eversham     . 

Benedictine 

701 

Worcestershire 

Ejmsham 

Do. 

1005 

Oxfordshire 

Faringdon     .     • 

Cistercian 

1203 

Berkshire 

Feme  •     •     •     • 

Premonstrant 

1214 

Ross-shire 

Ferns .     •     •     • 

Augustine 

1166 

Wexford 

Feversham   »     • 

Benedictine 

1140 

Kent 

Flezley    .     •     • 

Cistercian 

temp.  Steph. 

Gloucestershire 

Ford  .... 

Do. 

1141 

Devonshire 

Fountains     . 

Do. 

1132 

Yorkshire 

Frethelstoke 

Augustine 

8  Hen.  III. 

Devonshire 

Fomess   •     • 

Cistercian 

1127 

Lancashire 

Garendon 

Do. 

1133 

Leicestershire 

Glastonbury 

Benedictine 

954 

Somersetshire 

Glenluce .     •     • 

Cistercian 

1190 

Kirkcudbright 

'     Grace- Dieu  .      - 

Do. 

1226 

Monmouthshire 

.     Great  Corrall     . 

Augustine 

1202 

Ktldare 

Haddington 

'  Franciscan 

1178 

Haddingtonshire 

Haghman     •     - 

Augustine 

1110 

Shropshire 

Hagneby 

Premonstrant 

1175 

Lincolnshire 

Hales  Owen 

Do. 

temp.  John 

Shropshire 

;     Hasledon      • 

Cistercian 

temp.  Steph. 

Gloucestershire 

Hayles     • 

Do. 

1251 

Do. 

1     Hertland       •      • 

Augustine 

Devonshire 

Hexham  • 

Do. 

674 

Northumberiand 

;     Hilton      .      • 

Cistercian 

1223 

Staffordshire 

*     Holme-Cultrani 

Do. 

1150 

Cumberland 

'     Holy- Cross  . 

Do. 

1182 

Tippcrary 

Holy-Rood  . 

Augustine 

1128 

Edinburghshire 

Home  Lacy  • 

Premonstrant 

temp.  H.  III. 

Herefordshire 

Horton    • 

Benedictine 

970 

Dorsetshire 

Halme     •      • 

Carmelite 

1240 

I4ortbumberland 

Hmnberstayn 

•     *    * 

Benedictine 

1226 

Lincolnshire 

ABB 


ABBEYS, 


ABB 


NAMS. 

ORDER. 

DATE. 

COUNTY. 

Hurnston     .... 

Benedictine 

temp.  H.  U. 

Lincolnshire 

Hyde .    .    . 

1110 

Hampshire 

loolmkill 

Cluniac 

Argyleshire 

lespoint  .    . 

Cistercian 

1180 

Kilkenny 

Inchaffi:ay    . 

Augustine 

1200 

Perthshire 

Inchmahome 

Do. 

1200 

Do. 

Inys   .     .    . 

Cistercian 

1180 

Down 

Jedburgh     . 

Augustine 

temp.  Day.  I. 

Roxburghshire 

Jerval     .    . 

Cistercian 

1156 

Yorkshire 

Joneval  .    • 

Do. 

1145 

Do. 

Kelso .    .    . 

Tyrone 

1128 

Roxburghshire 

Kenilworth  . 

Augustine 

1122 

Warwickshire 

Keynsham   . 

k       • 

Do. 

1170 

Somersetdiire 

Kilcooly .     . 

Cistercian 

1200 

Tipperary 

Kilwinning  . 

Tyrone 

1140 

Ayrshire 

Kimmer  or  C 

Jyn 

unc 

ir  . 

Cistercian 

1200 

Merionethshire 

Kingswood  . 

Do. 

1139 

Wiltshire 

Kinner    .    . 

Do. 

1209 

Merionethshire 

KirkstaU 

Do. 

1152 

Yorkshire 

KirkRtead     . 

Do. 

1139 

Lincolnshire 

Kynloss  .    . 

Do. 

1150 

Moray 

TiRngdon  (W 

est 

Premonstrant 

1192 

Kent 

Langley  .    . 

Do. 

1198 

Norfolk 

Lanthony     . 

Augustine 

1136 

Gloucestershire 

Lavenden     . 

Premonstrant 

temp.  Hen.  IL 

Buckinghamshire 

Leicester 

Do. 

1143 

Leicestershire 

Leiston   .    . 

Premonstrant 

1182 

Suffolk 

Tyrone 

1140 

Lanarkshire 

Lesnes    . 

Augustine 

1178 

Gloucestershire 

Lindores . 

Tyrone 

1178 

Perthshire 

Llantamam 

Cistercian 

Monmouthshire 

Lolleshull 

Augustine 

1145 

Shropshire 

Louth  Park 

Cistercian 

1139 

Lincolnshire 

Machline 

Do. 

temp.  Day.  L 

Ayrshire 

Malmsbury 

Benedictine 

675 

WUtshire 

Margan  . 

Cistercian 

1147 

Glamorganshire 

Maynan  . 

Do. 

1283 

Denbighshire 

Meaux    . 

Do. 

1150  • 

Yorkshire 

Medmenhan 

Do. 

1200 

Buckinghamshire 

Mellifont 

Do. 

1142 

Louth 

Melrose  . 

Do. 

1136 

Roxburghshire 

Mereval  . 

Do. 

1148 

Warwickshire 

Michelney 

Benedictine 

939 

Somersetshire 

Milton     . 

Do. 

933 

Dorsetshire 

Missenden 

Augustine 

1133 

Buckinghamshire 

Ne&th      . 

Cistercian 

temp.  Hen.  I. 

Glamorganshire 

Nerminster 

Do. 

1138 

Northumberland 

Netley     . 

Do. 

1239 

Hampshire 

Newbo    . 

Premonstrant 

1198 

Lincolnshire 

Newbottle 

Cistercian 

1140 

Edinburghshire 

Newenham 

Do. 

1246 

Deyonshire 

Newhouse 

Premonstrant 

1143 

Lincolnshire 

Newry     . 

Cistercian 

1150 

Down 

ABB 


ABBEYS. 


ABB 


Northampton 

Nutley     . 

Oransey  . 

Osney 

Osulveston    • 

Owney 

Owrston  • 

Paisley     . 

Pershore .     * 

PipweU   *      . 

Quarre 

Radmore 

Ramsey    • 

Reading  • 

Revesby  - 

Rewley     •      • 

Rivaux     . 
Robertsbridge 

Roche 
Roncester 
Rosglas    . 
RulTord    • 
Russen     -      - 
Saffron  Walden 

Salley       •      - 
Saltry       -      • 
Saundle   • 
Scone 

Selby        -      - 
Shaftesbury 

Shap  -      •      * 

Shirebum 

Shrewsbury 

Sibton 

Spalding 

Stanlaw  -      - 

Stanley    . 

Stoneley  . 

St.  Agatha    . 

St.  Alban's 

St.  Augustine 

St.  Bennet  ot 

St.  James      -       .      x^ 

St.  John's,  Colchester 

St.  Mary 

St.  Mary         ^^^^ 
St.  Mary  de  Grace 
St.  M^ry  d^  Fr6 
St.  Mary    dc 

Salutis       -      • 
St.  Kadegand 
Strada    Florida 

Stratflear 


Hul 


VaUe 


me 


or 


} 
} 


ORDBR. 

Anjputine 

Do. 

Augustine 

Do. 

Do. 

Cistercian 

Templars 

Cluniac 

Benedictine 

Cistercian 

Do. 

Do. 

Benedictine 

Do. 

Cistercian 

Do. 

Do. 

Do. 

Do. 

Augustine 

Cistercian 

Do.    . 

Do. 

Benedictine 

Cisterdan 

Do. 

Do. 

Augustine 

Benedictine 

Do. 

Premonstrant 

Benedictine 

Do. 

Cistercian 

Benedictine 

Cistercian 

Do. 

Do. 

Premonstrant 

Benedictine 

Do. 

Do. 

Augustine 

Benedictine 

Cistercian 

Augustine 

Cistercian 

Augustine 

Cistercian 

Premonstrant 

Cistercian 


DATS. 

COUNTY. 

1112 

Northamptonshire 

1162 

Buckinghamshire 

St  Columba 

Argyleshire 

1129 

Oi^ordshire 

1175 

Leicestershire 

1205 

Limerick 

temp.  Hen.  II. 

Leicestershire 

1164 

Renfrewshire 

984 

Worcestershire 

1143 

Northamptonshire 

1132 

Hampshire 

1140 

Staffordshire 

969 

Huntingdonshire 

1121 

Berkshire 

1142 

Lincolnshire 

1280 

Oxfordshire 

1131 

Yorkshire 

1176 

Sussex 

1147 

Yorkshire 

1146 

Staffordshire 

Ireland 

1148 

Nottinghamshire 

1098 

Isle  of  Man 

1136 

Essex 

1146 

Yorkshire 

1146 

Huntingdonshire 

1164 

Argyleshire 

1114 

Perthshire 

1069 

Yorkshire 

888 

Dorsetshire 

temp.  Hen.  II. 

Westmoreland 

705 

Dorsetshire 

1083 

Shropshire 

1149 

Suffolk 

1052 

Lincolnshire 

1172 

Cheshire 

1151 

Wiltshire 

1154 

Warwickshire 

1151 

Yorkshire 

793 

Hertfordshire 

605 

Kent 

1020 

Norfolk 

1112 

Northampton 

1096 

Essex 

1139 

Dublin 

temp.  Ed.  III. 

Drogheda 

1349 

Middlesex     . 

1143 

Leicestershire 

tem]^.  Ed.  III. 

1191 

1294 


Ireland 

Kent 
Cardiganshire 


ABB 


ABBEYS. 


ABB 


NAME. 

ORDBK. 

DATS. 

COUNTY. 

Stratford  Longthome 

Cistercian 

1134 

Essex 

Stratmargel,  or  Stra- 1 
ta  MarceUa  .    .    j 

Do. 

1170 

Montgomeryshire 

Sulby 

Premonstrant 

1155 

Northamptonshire 

Sweetheart)  or  New  . 

Cistercian 

1296 

Kirkcudbright 

Swine 

Do. 

temp.  Steph. 

Yorkshire 

Swineshead      .    .    . 

Do. 

1134 

Lincolnshire 

Talley 

Premonstrant 

1197 

Carmarthenshire 

Tame 

Cistercian 

1137 

Oxfordshire 

Tavistock    .... 

Benedictine 

961 

Devonshire 

Tewkesbury     .    .    . 

Do. 

1102 

Gloucestershire 

Thometon  .... 

Augustine 

1139 

Yorkshire 

Thomey 

Benedictine 

972 

Cambridgeshire 

Tiltey 

Cistercian 

1152 

Essex 

Tintem 

Do. 

1131 

Monmouthshire 

Tintem 

Do. 

1308 

Wexford 

Titchfield     .... 

Premonstrant 

1231 

Hampshire 

Torr 

Do. 

1196 

Devonshire 

Tangland     .... 

Do. 

1160 

Kirkcudbright 

Tupholm     .... 

Do. 

temp.  H.  II. 

Lincolnshire 

Vale  Royal  .... 

Cisterdan 

1266 

Cheshire 

ValleCrucis     .    .    . 

Do. 

1200 

Denbighshire 

Vaudey 

Do. 

1147 

Lincolnshire 

Waltham  Abbey   .    . 

Augustine 

1062 

Essex 

Wardon 

Cistercian 

1135 

Bedfordshire 

Waverley     .... 

Do. 

1128 

Surrey 

Wearmouth      .    .    . 

Benedictine 

Durham 

Welbeck 

Premonstrant 

1153 

Nottinghamshire 

Wellow 

Augustine 

temp.  Hen.  I. 

Lincolnshire 

Wendling    .... 

Premonstrant 

temp.  H.  III. 

Norfolk 

West  Dereham     .    . 

Do. 

1188 

Do. 

West  Ham  .... 

Cistercian 

1135 

Essex 

Westminster    .    .    . 

Benedictine 

1049 

Middlesex 

Westwood  .... 

Augustine 

1178 

Kent 

Whalley 

Cistercian 

1296 

Lancashire 

Whitby 

Benedictine 

Wm.  Conq. 

Yorkshire 

Whiteland  .... 

Cistercian 

1143 

Wigmore     .... 

Augustine 

1179 

Herefordshire 

Wiuchcombe    .    .    . 

Benedictine 

985 

Gloucestershire 

Windham    .... 

Do. 

1107 

Norfolk 

Wobmm 

Cistercian 

1145 

Bedfordshire 

Abbey  gate-house,  a  lodge  for  warders 
or  porters  at  the  entrance  of  an 
abbey  edifice 

Abbot  J  the  superior  of  a  monastery  of 
monks  erected  into  an  abbey  or 
priory :  there  are  various  classes  of 
abbots,  as  mitred,  crosiered,  car- 
dinal,  regular,  and  commendatory 
abbots 

Abbofe  lodgings,  in  the  early  times  of 
English  ecclesiastical  architecture, 


a  complete  house,  with  hall,  chapel, 

and  every  convenience  for  the  rest- 

deuce  of  a  spiritual  baron 
Abbreviate,  to  contract  a  word    in 

writing  or  printing 
Abbreviations,  characters  or  marks 

over  letters  to  signify  either  a  word 

or  syllable 
Abele-tree,  a  species  of  white  poplar 
Aberration,  in  astronomy, an  apparent 

motion  of  the  celestial  bodies  oc- 


ABE 


ABUSES. 


ABU 


caaioned  by  the  progressWe  motion 
of  light  and  the  earth's  annual 
motion  in  its  orbit 

Aberration,  in  optics,  the  demtion 
or  dispersion  of  the  rays  of  light 
when  reflected  by  a  lens,  by  which 
they  are  prevented  from  meeting 
or  uniting  in  the  same  point,  called 
the  geometrical  focus ;  but  spread 
over  a  small  span,  they  produce  a 
confusion  of  images 

Ablactation,  in  gardening,  the  method 
of  grafting 

Ablaqueation,  the  opening  of  the 
ground  around  the  roots  of  trees, 
for  the  admission  of  the  air 

Aboard,  a  nautical  term,  the  inside  of 
a  ship,  or  to  go  on  board 

Aboutsh^,  the  situation  of  a  ship 
after  she  has  tacked 

Abomt-sledge,  the  largest  hammer  em- 
ployed by  smiths ;  it  is  slung  round 
near  the  extremity  of  the  handle, 
and  generally  used  by  under  work- 
men, called  hammer-men 

Abragion,  the  effect  produced  by  at- 
trition or  rubbing 

Abreast,  as  when  two  ships  have 
their  sides  parallel 

Abreuooir,  a  watering-place 

Abremvoir,  in  masonry,  the  interstice 
or  joint  between  two  stones  to  be 
filled  up  with  mortar  or  cement 

Abseioooj  a  geometrical  term  for  a  seg- 
ment cut  off  from  the  straight  line 
by  an  ordinate  to  a  curve 

Abiorbents,  in  chemistry,  those  earthy 
substances  capable  of  uniting,  by 
capillary  attraction,  a  large  pro- 
portion of  water:  such  are  mag- 
nesia,  lime,  and  clay,  when  d^ 
and  porous 

Absorption,  in  chemistry,  takes  place 
when,  by  the  combination  of  gases 
with  other  substances,  a  very  con- 
siderable diminntion  of  volume  is 
experienced:  it  differs  from  con- 
densation 
Abstract  (To),  a  term  used  by  arti- 
ficers and  surveyors  in  arranging 
and  apportioning  their  work,  to 
explain  and  price  it 
Abstract  mathematics,  otherwise  de- 
nominated pure  mathematics,  that 


branch  of  the  science  which  treats 
of  simple  properties,  magnitude, 
figure,  or  quantity,  alwolutely  and 
generally  considered 

Absurd,  a  term  used  in  demonstrating 
converse  propositions 

Abundant  number,  a  number  whose 
aliquot  parts,  added  together,  make 
a  sum  which  is  greater  than  the 
number  itself 

Abuses,  ** Architecture,'' says  PaUadlo, 
'*  being  an  imitatrix  of  Nature,  de- 
lights in  that  which  is  most  conso- 
nant with  her  prototype/'  Ancient 
edifices  were  built  with  wood,  trees 
forming  the  columns;  and  when 
architects  began  to  build  with  stone, 
they  made  the  columns  toimitate  the 
trunks  of  trees,  tapering  from  their 
bases.  Being  thus  originally  of 
wood,  and  therefore  liable  to  split 
when  much  loaded,  they  bound 
them  with  rings  at  top  and  bottom. 
Thus  the  bases  and  capitals  in  the 
different  orders  seem  originally  de- 
rived from  these  bandages,  though 
they  are  now  become  essential 
ornaments.  Thus  also  in  entabla- 
tures, the  triglyphs,  modillions,  and 
dentils  represent  the  ends  of  those 
beams  and  timbers  which  are  em- 
ployed for  the  support  of  the  floors 
and  roofs.  If,  therefore,  all  these 
conditions  be  duly  considered,  those 
practices  in  building  are  highly  to 
be  reprobated  which  are  in  oppo- 
sition to  that  analogy  which  should 
exist  between  the  original  and  its 
imitation,  or  which  depart  from  Na- 
ture and  the  simplicity  observable 
in  all  her  works. 

Consoles  or  cartouches,  which 
are  of  a  scroll-like  form,  should 
never  be  employed  for  the  appa- 
rent support  of  great  weights,  in 
place  of  columns  or  pilasters ;  nor 
should  they  ever  project  from,  or 
spring  out  of,  cornices. 

Pediments  and  frontispieces  over 
doors  and  windows,  or  elsewhere, 
should  on  no  account  be  broken  or 
disconnected  in  the  middle;  for 
the  intention  of  these  is  to  shelter 
the  parts  below  from  the  rain,  and 


7 


ABU 


ABUTMENTS. 


ACC 


this  result  is  completely  obviated 
by  such  a  practice. 

The  projecture  of  cornices, 
though  for  the  purpose  of  shelter- 
ing buildings,  should  not  be  more 
than  in  due  proportion  to  their 
height,  whether  or  not  accompanied 
by  columns ;  for  if  too  heavy,  they 
seem  to  threaten  with  danger  those 
who  are  under  them ;  and  if  too 
small  in  projection,  they  do  not 
properly  perform  their  office. 

Again,  those  columns  which  are 
feigned  to  be  composed  of  several 
pieces,  by  being  jointed  together 
ynth  rings,  should  be  carefully 
avoided,  because  the  more  soUd 
and  strong  the  columns  appear,  the 
better  they  seem  to  answer  the 
purpose  for  which  they  were  erect- 
ed, which  is  securely  to  receive 
the  superincumbent  loading. 

There  are  many  other  abuses 
which  the  authority  of  great  mas- 
ters may  sanction,  but  not  justify ; 
and  such  will  readily  occur  to  the 
student,  and  themselves  point  out  * 
that  they  ought  to  be  avoided 

Abutment,  the  solid  part  of  a  pier 
from  which  the  arch  springs 

Abutments,  the  extremities  of  a 
bridge,  by  which  it  joins  upon  the 
banks  or  sides  of  a  river,  &c. :  in 
carpentry  and  joinery,  the  junctions 
or  meetings  of  two  pieces  of  timber, 
of  which  the  fibres  of  the  one  run 
perpendicular  to  the  joint,  and 
those  of  the  other  parallel  to  it 

Abuttalg,  the  buttings  or  boundaries 
of  land 

Abyst,  in  heraldry,  the  centre  of  an 
escutcheon 

Aeaeio,  a  heavy,  durable  wood  of  the 
red  mahogany  character,  but  darker 
and  plainer ;  it  is  highly  esteemed 
in  ship-building 

AcademiOf  in  antiquity,  a  villa  or 
pleasure-house  in  one  of  the  sub- 
urbs of  Athens,  where  Plato  and 
other  philosophers  assembled 

Academician,  a  member  of  a  society 
or  academy  instituted  for  the  cul- 
tivation of  the  arts  and  sciences 

Acanthus,  the  plant  branna  ursina,  in 

8 


English  beards  breech,  the  leaves  of 
which  are  imitated  in  decorating 
the  Corinthian  and  Composite  ca- 
pitals of  columns 

Accelerated  motion,  a  force  acting  in- 
cessantly upon  a  body;  called  also  a 
constant  or  uniformly  accelerating 
force  when  the  velocity  increases 
equally  in  equal  times :  the  force  of 
gravity  near  the  earth's  surface  is 
of  this  kind;  it  generates  a  ve- 
locity of  32f  feet  in  each  second  of 
time ;  that  is,  a  body,  after  falling 
one  second,  acquires  a  velocity  of 
32^  feet;  after  falling  two  seconds, 
it  will  acquire  a  velocity  of  2  x  32^ 
feet ;  after  three  seconds,  a  velocity 
of  3  X  32^  feet,  and  so  on 

Accelerating  force,  in  physics,  the 
force  which  accelerates  the  motion 
or  velocity  of  bodies;  it  is  equal 
to,  or  expressed  by,  the  quotient 
arising  from  the  motion  or  absolute 
force,  divided  by  the  mass  or  the 
weight  of  the  body  moved 

Accelerative  or  retardative  force,  is 
commonly  understood  to  be  that 
which  affects  the  velocity  only,  or 
that  by  which  the  velocity  is  ac- 
celerated or  retarded;  it  is  equal 
or  proportional  to  the  motive  force 
directly,  and  to  the  mass  or  body 
moved  inversely 

Accesses,  approaches  or  passages  of 
communication  between  the  various 
apartments  of  a  buUding,  as  corri- 
dors 

Accessible,  in  surveying,  a  place  which 
admits  of  having  a  distance  or 
length  of  ground  measured  from 
it;  or  such  a  height  or  depth  as 
can  be  measured  by  the  application 
of  a  proper  instrument 

Accessories,  or  accompanimenis,  in 
painting,  secondary  objects  to  the 
principal  one  in  a  picture,  intro- 
duced as  explanatory  and  illus- 
trative of  the  scene:  sometimes 
they  are  considered  as  solely  con- 
tributing  to  the  general  effect  and 
harmony  of  the  piece 

Accidental  point,  in  perspective,  the 
point  in  which  a  right  line  draw^n 
from  the  eye,  parallel  to  another 


ACC 


ACROTERIA. 


ACT 


right  line,  cuts  the  picture  or  per- 
spectiTe  plane 

AecUmtyf  the  slope  or  steepness  of  a 
line  or  plane  inclined  to  the  hori- 
zon, taken  upwards;  in  contra- 
distinction to  declivity,  which  is 
taken  downwards 

Accovplement,  in  carpentry,  a  tie  or 
brace,  or  the  entire  work  when 
framed 

Jceretwnj  in  physics,  the  growth  or 
increase  of  an  organized  body 

Accroch^f  in  heraldry,  denotes  the 
hanging  of  one  thing  upon  another 

JccubUus,  a  room  annexed  to  large 
churches,  in  which  the  clergy  oc- 
casionally reposed 

Aeeric  acid,  in  chemistry,  an  acid 
formed  from  the  juice  of  the  maple- 
tree 

AcerrOf  in  antiquity,  an  altar  erected, 
among  the  Romans,  near  the  bed 
of  a  person  deceased,  on  which  his 
friends  daily  offered  incense  until 
his  burial 

Acetate  of  lead, — sugar  of  lead, — a 
compound  of  acetic  acid  and  lead 

Acetate  of  potash,  a  compound  of 
acetic  acid  and  potash,  produced 
by  dissolving  carbonate  of  potash 
in  distilled  vinegar 

Acetates,  crystallizable  salts,  formed 
by  the  combination  of  any  base  with 
acetic  acid,  named  also  radical  or 
pmre  vinegar 

Achromatic,  a  term  expressing  ab- 
sence of  colour :  in  optics,  applied 
to  telescopes  invented  to  remedy 
aberrations  and  colours 

Acids,  in  chemistry,  are  sour  to  the 
taste,  and  convert  vegetable  blues 
to  a  red  colour;  they  combine  with 
alkalies,  earths,  and  metallic  oxides, 
and  form,  with  them,  the  well- 
known  compounds  named  salts 

Acinose,  a  term  applied  to  iron  ore 
found  in  masses,  and  of  several  co- 
lours 
A-cock'biU,  in  navigation,  the  situ- 
ation of  the  yards  when  they  are 
topped  up  at  an  angle  with  the 
deck;  the  situation  of  an  anchor 
when  it  hangs  to  the  cat-head  by 
the  ring  only 


Acolyte,  in  the  ancient  church,  a 
person  who  trimmed  the  lamps, 
prepared  for  the  sacrament,  &c. 

Acoustics,  the  doctrine  or  theory  of 
sounds,  consisting  of  diacoustics, 
or  direct  sounds,  and  catacoustica, 
or  reflecting  sounds 

Acre,  a  measure  of  land,  containing, 
by  the  ordinance  for  measuring 
hmd  in  the  time  of  Edward  I.,  160 
perches  or  square  poles  of  land; 
and  as  the  statute  length  of  a  pole 
is  5i  yards  or  16i  feet,  the  acre 
contains  4840  square  yards,  or 
43560  square  feet.  The  chain 
with  which  land  is  now  commonly 
measured,  invented  by  Gunter,  is 
4  poles,  or  22  yards,  in  length ;  and 
the  acre  is  therefore  just  10  square 
chains;  and  as  a  mile  contains 
1760  yards,  or  80  chains,  in  length, 
the  square  mile  is  equal  to  640 
acres.  The  acre,  in  surveying,  is 
divided  into  4  roods,  and  the  rood 
into  4  perches 

Acrolithes,  in  sculpture,  statues,  the 
extremities  of  which  are  formed  of 
stone 

Acropolist  a  building  strictly  appli- 
cable to  a  Greek  city,  and  usually 
erected  upon  a  hill,  rock,  or  some 
natural  elevation,  and  devoted  to 
a  magnificent  temple ;  also  a  tower, 
castle,  or  citadel 

AcrostolioH,  in  ancient  naval  archi- 
tecture, an  ornament  of  the  prow 
or  forecastle  of  a  ship,  chiefly  of 
war,  most  frequently  circular  or 
spiral 

Acroteria,  small  pedestals  at  the 
angles  and  vertex  of  a  pediment : 
the  gate  of  the  Agora  at  Athens  is 
the  only  instance  in  which  they 
appear  in  Grecian  buildings 

Actinometer:  Sir  John  Herschel,  at 
the  third  meeting  of  the  British 
Association,  submitted  an  instru. 
ment  for  measuring  at  any  instant 
the  direct  heating  power  of  the 
solar  ray:  it  affords  a  dynamical 
measure  of  the  solar  radiation,  by 
receiving  a  quantity  of  heat  per 
second,  or  any  short  space  of  time, 
on  a  surface  exposed  to  the  sun. 


a5 


ACT 


ACTINOMETER. 


AER 


In  making  observations  with  this 
instnunenty  it  shoald  be  freely  ex- 
posed in  the  shade  for  one  minute, 
and  the  variation  read ;  afterwards 
expose  it  for  the  same  time  to  the 
soUur  action,  and  again  note  it ;  and 
lastly,  repeat  the  experiment  in  the 
shade :  the  mean  of  the  two  varia- 
tions in  the  shade  being  subducted 
from  the  variation  in  the  sun,  the 
excess  gives  the  dilatation  per  minute 
due  to  the  sun's  rays ;  the  quantity 
subducted  being  the  effect  of  the 
other  causes  at  the  time 

Aetust  a  Roman  measure  of  length, 
equal  to  120  Roman  feet 

Acute  angle,  in  geometry,  less  than  a 
right  angle,  and  measured  by  less 
than  90°,  or  a  quadrant  of  a  circle 

Acute-angled  coney  that  in  which  the 
opposite  sides  make  an  acute  at  the 
vertex,  or  whose  axis,  in  a  right 
cone,  makes  less  than  half  a  right 
angle  with  the  side 

Acute-angled  section  qfa  cone,  an  el- 
lipsis made  by  a  plane  cutting  both 
sides  of  an  acute-angled  cone 

Acute -angled  triangle ,  that  in  which 
the  three  angles  are  all  acute 

Adamant,  a  very  hard  stone,  used  by 
the  ancients  for  cutting  and  polish- 
ing other  hard  stones  and  glass 

AdeHng,  a  title  of  honour  given  to  the 
children  of  princes  among  the  An- 
glo-Saxons 

Adhesion,  the  force  with  which  differ- 
ent bodies  remain  attached  to  each 
other  when  brought  into  contact 

Adit,  the  passage  or  approach  to  a 
house;  applied  also  to  the  hori- 
zontal shaft  of  a  mine,  driven  for 
the  purposes  of  ventilating,  water- 
ing, or  draining 

Adit  level,  in  mining,  a  horizontal 
excavation  through  which  the  water 
is  drawn  by  the  engine 

Adjacent  angle,  in  geometry,  an  angle 
immediately  contiguous  to  another, 
so  that  one  side  is  common  to  both 

Adjutage  (Ajutage),  or  Jet  d*eau,  a 
tube  fitted  to  the  aperture  of  a  ves- 
sel through  which  water  is  to  be 
played 

Adonia^  a  festival  celebrated  in  ho- 
— 


nour  of  Aphrodite  and  Adonis  in 
most  of  the  Grecian  cities 

Adrift,  the  condition  of  a  vessel  broken 
from  her  moorings 

Adumbration,  in  heraldry,  a  fig^ure 
painted  of  the  same  colour  as  the 
ground  of  the  field,  but  darker 

Adytum,  the  most  sacred  place  in  the 
heathen  temples ;  the  Holy  of  Ho- 
lies ;  in  Christian  architecture,  the 
chancel  or  altar-end  of  a  church 

Adze,  an  edged  tool  used  to  chip  sur- 
faces in  a  horizontal  direction ;  the 
axe  being  employed  to  chop  mate- 
rials in  vertical  positions 

^ccle8iolo,m  Domesday  Book,  a  cha- 
pel  subordinate  to  the  mother  church 

^des,  an  inferior  kind  of  temple ;  in 
Christian  architecture,  a  chapel ; 
also  sometimes  applied  to  a  house 

^dicula,  a  small  chapel,  house,  or 
building  of  any  kind;  not  un&e- 
quently  applied  to  the  niches  of 
tabernacles  in  a  wall  which  held 
statues  of  the  lares  or  penates 

jEgricanes,  a  name  given  to  rains' 
heads  when  sculptured  on  friezes, 
altars,  &c. 

jEolipile,  in  hydraulics,  an  instrument 
consisting  of  a  hoUow  metallic  ball 
with  a  slender  neck  or  pipe  pro- 
ceeding from  it,  which,  being  filled 
with  water,  produces  a  violent  blast 
of  wind 

jEolus,  a  small  portable  machine  for 
refreshing  and  changing  the  air  of 
apartments 

^rarium,  a  treasury  among  the  Ro- 
mans ;  the  place  where  public  mo- 
ney was  deposited 

Aerial  perspective,  the  relative  appa- 
rent recession  of  objects  from  the 
foreground,  owing  to  the  quantity 
of  air  interposed  between  them  and 
the  spectator 

Aerology,  the  doctrine  or  science  of 
the  air 

Aerometer,  an  instrument  contrived 
to  ascertain  the  mean  bulk  of  gases 

Aerometry,  the  science  of  measuring 
the  air,  its  powers  and  proper- 
ties 

Aeronautics,  the  art  of  sailing  or  float. 
ing  in  the  air 


AER 


AIR-PUMP. 


AIR 


] 


Aero»tatic9,    the    doctrine    of    the 
weight,  pressure,   and  balance  of 
the  air  and  atmcraphere 
jEruffo,  rust,  more  especially  that  of 

copper;  verdigris 
JEstheticSf  the  power  of  perception  by 
means  of  the  senses  :  the  word  im- 
plies the  perception  and  the  study 
of  those  qualities  which  constitute 
the  beautiful  and  artistic,  and  fonn 
the  finer  essence  of  all  productions 
of  fine  art.  It  carries  with  it,  there- 
fore, a  more  exact  and  philosophic 
meaning  than  the  word  '  taste.'  In 
its  adjective  form,  in  which  it  more 
frequently  occurs,  it  is  particularly 
us^l,  as  no  adequate  epithet  can 
be  substituted  for  it.  Thus  we  speak 
of  the  *  aesthetic  sense,'  of  *  aesthetic 
feeling,'  or  *  study,'  or  *  principles,' 
&c.;  but  we  cannot  correctly  say 
the  'tasteful  sense,'  or  *  tasteful 
study' 
Aetoma,  a  pediment,  or  the  tympanum 

of  a  pediment 
Affinity,  in  chemistry,  the  power  by 
which  the   ultimate   particles   of 
matter  are  made  to  unite,  and  kept 
united 
Affiujp,  a  flow  of  electric  matter  to  a 
globe  and  conductor,  in  opposition 
to  efflune,  from  them 
After,  in  ship-building,  implies  a  con- 
nexion,  as  belonging  to  the  after- 
body, after-timber,  &c. 
Affolma,  a  sculptural  ornament   or 

image 
Ager,  a  Roman  acre  of  land 
Agger,  a  heap  or  mound  of  any  kind, 

formed  of  stone,  wood,  or  earth 
Agglutination,  the  cohesion  of  bodies 
Aggregation,  in  chemistry,  the  collec- 
tion of  bodies,  solid,fluid,  or  gaseous 
Agora,  a  place  of  public  assembly  in 
a  Greek  city  for  the  transaction 
of  all  public  business;  a  market- 
place 
AguiUa,  an  obelisk,  or  the  spire  of  a 

church  tower 
A'huU,  the  condition  of  a  vessel  when 
she  has  all  her  sails  furled,  and  her 
helm  lashed  a-lee 
AvT'casing,    the    sheet-iron    casing 
which  surrounds  the  base  of  the 


11 


chimney  of  a  steam  vessel,  to  pre- 
vent too  great  a  transmiasioD  of 
heat  to  the  deck 

Air-drains,  cavities  between  the  ex- 
ternal walls  of  a  building,  protected 
by  a  wall  towards  the  earth,  which 
is  thus  prevented  from  causing 
dampness 

Atr-eecaqfe,  a  contrivance  for  letting 
off  the  air  from  water-pipes 

Air-holes,  those  made  for  admitting 
air  to  ventiUte  apartments 

Air'machine,  in  mining,  the  apparatus 
used  for  forcing  purer  air  into  or 
withdrawing  foul  air  from  parts 
badly  ventilated 

Air-pipes,  in  mining,  tubes  or  pipes 
of  iron  or  wood,  for  ventilating 
under  ground,  or  for  the  convey- 
ance of  fresh  air  into  levels  having 
but  one  communication  with  the 
atmosphere,  and  no  current  of  air : 
also  used  for  clearing  foul  air  from 
the  holds  of  ships,  or  other  close 
places 

Air-pump,  a  pneumatic  instrument, 
by  means  of  which  the  air  is  ex- 
hausted out  of  the  proper  vessels : 
its  effects  are  produced  by  the  elas- 
ticity of  the  air;  and  as  at  each 
stroke  of  the  pump  only  a  part  of 
the  remaining  air  is  vnthdrawn,  an 
absolute  vacuum  cannot  be  obtain- 
ed, although  so  near  an  approxi- 
mation to  it  may  be  had  as  to 
remove  the  general  effects  of  the 
atmosphere.  The  proportion  of 
the  air-pump,  as  given  by  Watt, 
is  usually  about  two-thirds  of  the 
diameter  of  the  cyUnder,  when  the 
length  of  the  stroke  of  the  air- 
bucket  is  half  the  length  of  the 
stroke  of  the  steam  piston.  The 
area  of  the  passages  between  the 
condenser'-and  the  air-pump  should 
never  be  less  than  one-fourth  of 
the  area  of  the  air-pump.  The 
apertures  through  the  air-bucket 
should  have  the  same  proportion  ; 
and,  if  convenient,  the  discharging 
flap  or  valve  should  be  made  larger. 
The  capacity  of  the  condenser 
should  at  least  be  equal  to  that  of 
the  air-pump ;  but,  when  conveni- 


AIR 


AIR-VESSEL. 


ALG 


ence  will  admit  of  it,  the  larger  it 
is  the  better 

Air'pump  buckett  an  open  piston, 
with  valves  on  the  upper  surface, 
opening  upwards,  so  as  to  admit 
the  air  and  water  in  the  down- 
stroke,  and  lift;  it  with  the  up- 
stroke of  the  pump 

Air-pump  rodf  the  rod  for  connecting 
the  bucket  to  the  beam 

Air-tinty  in  painting,  the  tint  by 
which  the  distant  parts  of  a  land- 
scape are  rendered  more  distinct, 
or  sometimes  giving  a  misty  appear- 
ance to  the  whole :  it  is  generally 
compounded  of  a  blue-grey,  occa- 
sionally approaching  to  purple 

Air-trapf  a  trap  immersed  in  water, 
to  prevent  foul  air  arising  from 
sewers  or  drains 

Air-valvcy  applied  to  steam  boilers 
for  the  purpose  of  preventing  the 
formation  of  a  vacuum  when  the 
steam  is  condensing  in  the  boiler 

Air-vessel,  the  closed  cylinder  con- 
nected to  the  discharge-pipe  of  a 
force-pump,  and  by  the  action  of 
which  the  water  ejected  by  the  pis- 
ton or  plunger  of  the  pump  enters 
the  cylinder  and  compresses  the  air 
within ;  it  acts  as  a  spring  during 
the  return  stroke,  and  thus  renders 
the  stream  constant :  also  a  cham- 
ber containing  air,  attached  to 
pumps  and  other  water  engines,  for 
the  purpose  of  making  the  discharge 
constant  when  the  supply  is  inter- 
mittent 

Aislct  the  side  passage  or  division  of 
a  church,  partially  separated  from 
the  nave  and  choir  by  columns  or 
piers 

Aitre,  a  hearth  or  chimney 

Alabaster f  a  species  of  gypsum,  a  mi- 
neral substance,  chemically  termed 
sulphate  of  lime:  also  a  box  or 
vase  for  holding  perfumes  and  oint- 
ments ;  so  called  because  originally 
made  of  alabaster,  and  for  which 
the  variety  called  onyx-alabaster 
was  usually  employed 

Alba,  a  beacon  or  light-house 

Albarium,  white-wash ;  according  to 
Pliny  and  Vitruvius,  a  white  stucco 


or  plaster,  made  of  a  pure  kind  of 
lime  burned  from  marble,  and  used 
to  spread  over  the  roofs  of  houses 

Albarium  opus,  according  to  Vitru- 
vius, a  species  of  stucco-work 

Alcahestf  in  ancient  chemistry,  a 
universal  dissolvent 

Alcha,  a  cellar,  pantry,  or  an  apart- 
ment for  the  reception  of  drinking 
vessels 

Alchemist,  one  skilled  in  the  art  of 
alchemy  or  chemistry 

Alchemy,  that  branch  of  chemistry 
which  presumes  the  transmutation 
of  metals :  Lord  Bacon  calls  it  the 
art  of  distilling  or  drawing  qain- 
tessences  out  of  metals  by  fire 

Alcohol,  in  chemistry,  a  pure  spirit 

Alcoholometer,  an  instrument  for  as- 
certaining the  strength  of  spirits 

Alcorans,  in  oriental  architecture, 
high  slender  towers  attached  to 
mosques,  in  which  the  Koran  is 
read 

Alcove,  a  recess  in  a  chamber,  or  a 
recess  separated  from  other  parts 
of  the  room  by  columns,  antse,  and 
balusters 

Alder,  a  wood  formerly  much  used. 
The  common  alder  seldom  exceeds 
40  feet  in  height,  is  very  durable 
under  water,  and  was  used  for  the 
piles  of  the  Rialto  at  Venice,  the 
buildings  at  Ravenna,  &c.:  it  w^as 
formerly  much  used  for  pipes 
pumps,  and  sluices 

Aleaceria,  a  palace,  castle,  or  other 
large  edifice 

Aleatorium,  an  apartment  in  a  Roman 
house  appropriated  to  the  use  of 
persons  playing  with  dice 

A-lee,  a  term  used  to  denote  the  posi- 
tion of  the  helm  when  it  is  put 
in  the  opposite  direction  from  that 
in  which  the  wind  blows 

Alembic,  in  chemistry,  a  vessel  u6ed 
in  distillation 

Aleois,  loopholes  in  the  walls  of  a  castle 
or  fortification,  through  which  ar- 
rows may  be  discharged 

Algaroth,  in  chemistry,  a  white  pow- 
der obtained  from  muriate  of  anti- 
mony 

Algebra,    literal  arithmetic,   or    the 


ALH 


ALIEN  PRIORIES. 


AL] 


science  by  which  quantity,  and  the 
operations  of  quantity,  are  ex- 
pressed by  conventional  symbols 

Alhambra,  in  Saracenic  architecture, 
the  royal  palace  of  the  kings  of 
Granada 

Alien  I^riitries,  cells  or  small  religious 


houses  erected  in  different  coun< 
tries,  and  distinguished  as  aUeii 
from  their  dependence  on  large 
foreign  monasteries.  The  following 
is  a  list  of  those  established  in 
England,  with  the  dates  of  theii 
foundation : 


IfAME. 

ORDER. 

DATE. 

COUNTY. 

Alley 

Benedictine 

1160 

Herefordshire 

Alberbury     -      .      .      . 

Do. 

Henry  I. 

Shropshire 

Allerton  Mallever  . 

Do. 

1364 

* 

Yorkshire 

Andewell      •      .      .      . 

Do. 

Hampshire 

Andover 

Do. 

Wm.  Conq. 

Do. 

Appledercomb  . 

Do. 

Henry  III. 

Isle  of  Wight 

Astley 

Do. 

1160 

Worcestershire 

Avebnry 

Do. 

Wm.  Conq. 

Wiltshire 

Axmoath.       .      •      •      • 

Do. 

Henry  II. 

Devonshire 

Beccanford  .      .      .      . 

Augustine 

Gloucestershire 

Begare 

Henry  III. 

Yorkshire 

Birstall 

Benedictine 

1115 

Do. 

Blakenbam  .      .      .      . 

Do. 

Wm.  Rufus 

Suffolk 

Brimsfield     .      .      -      • 

Do. 

Gloucestershire 

Burne  (College  of)      . 

Do. 

1200 

Kent 

Burwell 

Do. 

1318 

Lincolnshire 

Cameringham    . 

Premonstrant 

Richard  II. 

Do. 

Carisbrook    .       .       .      - 

Benedictine 

1071 

Isle  of  Wight 

Charleton      .      .      .      . 

Premonstrant 

1187 

Wiltshire 

Charlton  upon  Otmoor 

1081 

Oxfordshire 

Clare 

Benedictine 

1090 

Suffolk 

Clatford 

Do. 

Wm.  Conq. 

Wiltshire 

Cogges 

Black  Monks 

1103 

Oxfordshire 

Cosham    •      •       -       •     • 

Benedictine 

King  Steph. 

Wiltshire 

Covenfaam     .       .       •     • 

Do. 

1082 

Lincolnshire 

Cowike 

Do. 

Henry  II. 

Devonshire 

Cresswell       .       .       -     • 

Do. 

King  John 

Herefordshire 

Be  la  Grave         -       -     • 

Do. 

1169 

Bedfordshire 

Ecclesfield     -       -       -    • 

Do. 

Yorkshire 

£dith  Weston    -       -     • 

Do. 

Henry  I. 

Rutlandshire 

FiAmgham       .       -       •    • 

Do. 

1163 

Hampshire 

Fieldallyin^          -       -    • 

Cistercian 

Henry  II. 

Norfolk 

Frampton       .       -       -    • 

Black  Monks 

King  Steph. 

Dorsetshire 

GoldcUff.       .        -       -     • 

Benedictine 

1113 

Monmouthshire 

Grosmont       -       -       •     • 

Do. 

King  John 

Yorkshire 

Hagham  .       -       -       •     • 

Cluniac 

Richard  II. 

Lincolnshire 

Haghe      .       -       -       •     • 

Benedictine 

1164 

Do. 

Hamele    .       -       -        *     • 

Cistercian 

Hampshire 

Hinckley         .       -        •     • 

Benedictine 

1173 

Leicestershire 

Horkeslegli  .       -       •     • 

Do. 

Wm.  Conq. 

Gloucestershire 

Hou    .      -       •       -        •     • 

Do. 

1096 

Sussex 

Ipilpen     .       -       -       •     • 

Do. 

1274 

Devonshire 

Lancaster       .       -       •     • 

Do. 

1004 

Lancaster 

Lappele    .       -       -       '     * 

Black  Monks 

Edw.  Conf. 

Staffordshire 

Lavenestre    -       -       •     • 

Benedictine 

Wm.  Conq. 

Sussex 

13 


ALI 


ALIEN  PRIORIES. 


AI.I 


NAME. 

Lasingham  .    . 
Jiewuham   • 
Limburgh  Magna 
Llangewith  .    . 
Llangkywan     . 
Lodnea   .    .    . 
Long  Bengton . 
Lynton   .    .    . 
Mersey   .    .    • 
Minster  Lovel  . 
Minting  .    •    • 
Modbury     .    . 
Monkenlane 
Monks  Kirby    . 
Okebum .    .    • 
Okerington  .    . 
Overdon      .    . 
Newington  LongCTille 
New  Romney 
Noent     .    . 
Paunsfield    . 
Povington    . 
Riselipp  .    . 
Rotberfield  . 
Scardeburgh 
Sidmouth     . 
Spedtesbury 
Sporle     .    . 
Stayning 
Steventon    . 
Stoke  Curcy 
Stratfieldsay 
St.  Clare 
St.  Cross 
St.  Helen's 
St.  Michaers  Mount 
Sumpting 
Swavesey 
Takeley  . 
Talcarr   . 
Thurlegh 
Tofte.    . 
Tooting  . 
Tregony . 
Tykeford 
Upbayen 
Ware.    . 
Wareham 
Warmington     .    . 
Wedon  on  the  Street 
Wedon  Pinkney    . 
Welles    . 
Wenge    . 


ORDB&. 

Benedictine 

Cistercian 

Benedictine 

Black  Monks 

Benedictine 

Do. 

Benedictine 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Benedictine 
Do. 
Do. 
Do. 

Do. 

Cistercian 
Benedictine 
Carthusian 
Black  Monks 

Black  Monks 
Benedictine 
Do. 
Cluniac 

Do. 
Benedictine 

Do. 


CeU  of  Monks 
Benedictine 
Black  Monks 

Benedictine 


Do. 

Do. 
Do. 
Do. 


DATE. 

Wm.  Rufas 

before  Conq. 

Richard  II. 

King  Steph. 

1183 
Henry  I. 

1175 

1255 
Edw.  Conf. 

1259 

1129 

1275 
Richard  II. 

1077 

1149 
Wm.  Conq. 

1217 
Henry  I. 

Wm.  Conq. 
King  Steph. 

Wm.  Rufus 

800 

King  John 

Wm.  Conq. 

Henry  I. 

1256 

Sax.  period 

Henry  I. 

Henry  II. 

1170 

1153 
1155 
1085 

Wm.  Conq. 
Edward  I. 


Henry  I. 
Wm.  Conq. 

1267 

Wm.  Rufus 

King  Steph. 

1081 

Henry  I. 

Henry  I. 
Wm.  Conq. 

Henry  I. 
Wm.  Conq. 


COUNTT. 

Norfolk 

Kent 

Lincolnshire 

Glamorganshire 

Monmouthshire 

Dorsetshire 

Lincolnshire 

Cambridgeshire 

Essex 

Oxfordshire 

Lincolnshire 

Devonshire 

Herefordshire 

Warwickshire 

Wiltshire 

Devonshire 

Northamptonshire 

Buckinghamshire 

Kent 

Gloucestershire 

Essex 

Dorsetshire 

Middlesex 

Sussex 

Yorkshire 

Devonshire 

Dorsetshire 

Norfolk 

Sussex 

Berkshire 

Somersetshire 

Berkshire 

Carmarthenshire 

Isle  of  Wight 

Do. 

Cornwall 

Sussex 

Cambridgeshire 

Essex 

Cornwall 

Kent 

Norfolk 

Surrey 

Cornwall 

Buckinghamshire 
WUtshire 

Hertfordshire 

Dorsetshire 

Warwickshire 

Northamptonshire 

Do. 

Norfolk 

Buckinghamshire 


14 


kL.1 


ALIEN  PRIORIES. 


ALT 


NAMIS. 

ORDBK. 

Wenghale    .... 

West  Ravendale    •     . 

Premonstrant 

West  Shirbome     .     . 

Benedictine 

Westwood    .... 

Do. 

Willesford   .... 

Do. 

Wilmington      .     .     . 

Do. 

Winterbury  Wast .     . 

Do. 

Wirham 

Do. 

Wolfiicheston  .     •     . 

Black  Monks 

Wolton  Wawm      .     . 

Benedictine 

DATE. 

Henry  III. 
1202 

Henry  I. 

Henry  II. 
King  Steph. 
Wm.  Rufus 

1214 
Richard  I. 
Wm.  Conq. 

Henry  I. 


COUNTY. 

Lincolnshire 

Do. 

Hampshire 

Worcestershire 

Lincolnshire 

Sussex 

Dorsetshire 

Norfolk 

Warwickshire 

Do. 


JHpterion,  in  ancient  Rome,  a  room 
wherein  bathers  anointed  themselves 

Atiquot  part,  such  part  of  a  n  amber 
as  will  exactly  divide  it  without  a 
remainder ;  a  part  as,  being  taken 
or  repeated  a  certain  number  of 
times,  exactly  makes  up  or'is  equal 
to  the  whole :  thus  1  is  an  aliquot 
part  of  6  or  any  other  whole  number 

Alkalescent^  a  chemical  term  applied 
to  such  animal  and  vegetable  sub- 
stances  as  have  a  tendency  to  pro- 
duce muriate  of  ammonia,  or  vola- 
tile alkali 

Alkalif  in  chemistry:  potash  and  soda 
were  usually  termed  fixed,  and  am- 
monia volatile,  alkalies:  alkalies 
combine  with  and  neutralize  acids, 
thereby  producing  salts ;  they  also 
change  vegetable  blues  to  green 

AUalimeter,  an  instrument  for  mea- 
suring and  determiningthe  quantity 
and  strength  of  alkalies 

AUette,  used  to  express  a  small  wing 
of  a  building;  also  applied  to  a  pilas- 
ter or  buttress 

AUey,  a  passage  from  one  part  of  a 
building  to  another ;  a  passage  or 
court  with  houses 

AUigatUm,  one  of  the  rules  of  arith- 
metic, by  which  are  resolved  ques- 
tions which  relate  to  the  compound- 
ing or  mixing  together  of  divers 
simples  or  ingredients 

AUoriumi  a  piazza,  corridor,  or  co- 
vered way  in  the  flank  of  a  building 

AUoy^  baser  metal,  commonly  mixed 
with  the  precious  metals 

AOuoium,  the  debris  occasioned  by 
causes  still  in  operation,  as  deposits 
left  by  the  action  of  rivers,  floods, 
and  torrents 


U 


Almacantar,  lines  parallel  to  the  ho- 
rizon, and  conceived  to  pass  through 
every  degree  of  the  meridian 

Almehrad,  a  niche  in  the  mosques  of 
the  .Arabs,  for  praying 

Almond-tree,  a  hard,  heavy,  oily  or 
resinous  kind  of  wood,  somewhat 
pliable 

Almonry  f  a  room  or  place  where  alms 
were  formerly  distributed  to  the 
poor 

Almshouse^  a  house  for  the  reception 
and  support  of  the  poor 

Aloof,  in  navigation,  to  keep  the  ship 
near  the  wind  when  sailing  upon  a 
quarter  wind 

Alguifore,  lead  ore  found  in  Cornwall, 
and  used  by  potters  to  green  var- 
nish their  wares 

AlruncB,  small  images  carved  out  of 
roots  of  trees,  and  anciently  held  in 
much  veneration  by  the  northern 
nations 

Altar,  an  elevated  table  of  either 
stone,  marble,  or  wood,  dedicated 
to  the  ceremonies  of  religious  wor- 
ship. "  And  Noah  builded  an  altar 
unto  the  Lord ;  and  took  of  every 
clean  beast,  and  of  every  clean  fowl, 
and  offered  burnt  offerings  on  the 
altar."— Gen.  viii.  20. 

Altar-piece,  the  ornamental  sculpture 
or  painting  behind  the  altar  in  a 
Christian  church 

Altar-screen,  the  back  of  an  altar,  or 
the  partition  by  which  the  choir  is 
separated  from  the  presbytery  and 
lady-chapel 

Altars,  among  the  Greeks,  according 
to  Wilkins's  *  Vitruvius,'  faced  the 
east,  and  were  placed  lower  than 
the  statues  arrangedabout  the  cella, 


ALT 


ALTAR. 


AMY 


in  order  that  those  who  offered  up 
prayers  and  sacrifices  might  know, 
from  their  different  heights,  to 
what  particular  deities  the  several 
altars  were  consecrated 

Altare  chorif  a  reading  desk  in  a 
church 

Altare  farunii  the  lustre,  chandelier, 
or  cresset,  suspended  over  an  altar 

Altimetryf  the  art  of  taking  or  mea- 
suring altitudes  or  heights 

Altitttdey  of  a  figure,  the  length  of  a 
line  drawn  perpendicularly  from 
the  vertex  to  the  base 

Alto-rilievot  highly  relieved  sculpture 
representing  figures  either  entirely 
or  nearly  detached  from  the  back- 
ground 

Alumi  a  salt  extracted  from  various 
minerals  called  alum  ores;  of  great 
use  to  chemists,  dyers,  and  artists ; 
acid  and  sharp  to  the  taste 

Aluminum^  in  chemistry,  the  metallic 
base  of  the  earth  alumina,  which  is 
found  in  nature  along  with  some 
oxides,  and  acting  as  an  acid :  these 
combinations  are  termed  ahAmin- 
atesy  and  are  insoluble  in  acids 

Alveus,  in  hydrography,  the  channel 
or  belly  of  a  river 

Amalganit  a  mixture  of  mercury  with 
any  other  metal,  tin,  lead,  &c. 

AmbituSf  an  enclosure,  more  particu- 
larly applied  to  the  space  around  a 
building,  as  a  church-yard  or  a 
castle-yard 

Ambo,  Ambone,  a  rostrum  or  raised 
platform 

AmbulatiOj  walks,  or  places  of  exer- 
cise, according  to  Vitruvius,  adja- 
cent to  theatres 

Ambulatory y  a  cloister,  gallery,  or  alley 

Ammonia,  in  chemistry,  a  compound 
of  hydrogen  and  azote,  which  can 
only  be  exhibited  pure  in  a  state  of 
gas;  with  carbonic  acid,  it  forms 
volatile  alkali  or  hartshorn.  Am- 
monia  is  found  in  the  urine  of 
animals,  in  the  earth,  and  also  in 
the  atmosphere:  it  was  formerly 
obtained  by  distilling  horn,  from 
which  it  acquired  the  name  of 
hartshorn.  It  is  generally  prepared 
from  chloride  of  ammonium  or  sal- 

16 


ammoniac,  from  which  it  receives 
its  name 

Ammoniac,  a  gum  used  for  metallic 
vessels 

Amphiprostyle,  a  term  applied  to  a 
temple  virith  a  portico  in  front  and 
also  behind 

Amphitheatre,  an  edifice  formed  by 
the  junction  of  two  theatres  at  the 
proscenium,  so  as  to  admit  of  seats 
all  round  the  periphery 

Amphitheatre,  in  Roman  antiquity,  a 
large  edifice  of  an  elliptic  form, 
with  a  series  of  rising  seats  or 
benches  disposed  around  a  spacious 
area,  called  the  arena,  in  which 
the  combats  of  gladiators  and  wild 
beasts,  and  other  sports,  were  ex- 
hibited. It  consisted  exteriorly  of 
a  wall  pierced  in  its  circumference 
by  two  or  more  ranges  of  arcades, 
and  interiorly  of  vaulted  passages 
radiating  from  the  exterior  arcades 
towards  the  arena,  and  several 
transverse  vaulted  corridors  which 
opened  a  free  communication  to 
the  stairs  at  the  ends  of  the  passage 
and  to  every  other  part  of  the 
building ;  the  corridors  and  ranges 
of  seats  forming  elliptical  figures 
parallel  to  the  boundary  wall 

Amphithura,  in  the  Greek  Church 
the  veil  or  curtain  opening  to  the 
folding  doors,    and  dividing    the 
chancel  from  thfe  rest  of  the  church 

Amphora  (pi.  amphorci),  an  earthen 
vase  or  jar,  with  a  handle  on  each 
side  of  the  neck ;  among  the  an- 
cients, the  usual  receptacles  of 
olives, grapes,  oil,  and  wine.  Hence 
in  decoration,  amphoral  means* 
shaped  like  an  amphora  or  vase 

Amulet,  in  decoration,  a  figure  or  cha- 
racter to  which  miraculous  powers 
were  supposed  to  be  attached,  and 
which  particularly  distinguished 
the  buildings  of  Egypt 

Amusdum,  anciently  a  carpenter's 
and  mason's  instrument,  the  use  of 
which  was  to  obtain  a  true  plane 
surface ;  but  the  statements  of  the 
ancient  writers  render  its  construc- 
tion extremely  difiScult 

Amylum,  in  chemistry,  starch 


ANA 


ANGLES. 


ANG 


Anabathray  steps  to  any  elevated  8itu- 
atioD,  as  the  anabathra  of  theatres, 
pulpits,  &c. 

^no^a/Arum,  apulpit,  desk,  or  highseat 

Anacampteriay  the  lodgings  of  per- 
sons who  fled  for  sanctuary  to  pri- 
vileged religious  houses 

Anacan^tics,  the  doctrine  of  reflected 
light 

Anaehorita^  the  cell  of  a  hermit 

AnaclagHcSy  the  doctrine  of  refracted 
light 

Anaglyph,  an  engraved,  embossed,  or 
chased  ornament 

Anaglypha,  chased  or  embossed  ves- 
seis  made  of  bronze  or  the  precious 
metals,  which  derived  their  name 
from  the  work,  on  them  being  in 
relief,  and  not  engraved 

Anofflyphic  worJt,  a  species  of  sculp- 
ture wherein  figures  are  made  pro- 
minent by  embossing 

AfuUemnutf  a  projection  of  the  meri- 
dian; used  also  to  designate  a  wall, 
pier,  or  buttress 

Analoghtm,  a  tomb  over  the  bodies  of 
saints;  idso  a  term  formerly  applied 
to  pulpits  wherein  the  gospels  and 
epistles  were  read 

AnamarpAosiSftidistOTted  piece  of  per- 
spective, oc<uisioned  by  too  near  a 
point  of  view,  and  from  the  injudi- 
cious attitude  or  situation  of  the 
object,  but  perfectly  true  accord- 
ing  to  the  laws  oi  perspective 

Anchor,  an  instrument  used  for  the 
mooring  of  ships ;  in  architecture, 
a  decorative  moulding  used  in  the 
orders,  and  applied  to  the  echinus ; 
also  an  ornament  in  the  form  of  the 
fluke  of  an  anchor,  frequently  cut 
in  the  ovolo  of  Ionic  capitals,  and 
in  the  bed-mouldings  of  Ionic  and 
Corinthian  cornices 

Anchor-stock,  in  ship-building,  a  me- 
thod of  working  planks,  by  which 
the  abutments  are  to  be  disposed 
near  the  middle  of  those  planks 
which  are  above  or  below  them 

Aneon,  in  decoration,  a  carved  drink- 
ing-cup  or  horn  ;  an  elbow  or 
angle,  or  corner-stone.  The  An^ 
cona  foot  measure  is  1*282  of  an 
English  foot 

17 


Ancone,  a  console  or  ornament  cut  on 
the  key-stone  of  an  arch 

AnconeSf  trusses  or  consoles  employed 
in  the  dressings  of  apertures ;  also 
used  to  signify  the  corners  or  quoins 
of  walls,  cross-beams,  or  rafters,  &c. 

Andironf,  iron  bars  with  legs  to  sup- 
port  logs  of  wood  in  fire-places 

Androidt  in  mechanics,  an  automaton 

AndroKf  an  apartment,  cloister,  or 
gallery,  assigned  to  the  male  part 
of  a  monastic  establishment;  ap- 
plied also  to  the  space  in  a  church 
by  which  the  men  were  separated 
from  the  women 

Anemography,  a  description  of  the 
winds 

Anemometer,  an  instrument  for  mea- 
suring the  force  of  the  wind 

Anemoeccpe,  a  machine  to  denote 
the  changes  of  the  wind  or  weather 

Any^fortum,  among  the  ancients,  a 
narrow  laiae  between  two  rows  of 
houses 

Angle,  in  geometry,  the  mutual  in- 
clination of  two  lines  meeting  in  a 
point 

Angle-bar,  in  joinery,  the  upright  bar 
at  the  angle  of  a  polygonal  window 

Angle-bead,  a  vertical  bead,  commonly 
of  wood,  fixed  to  an  exterior  angle, 
and  flush  vrith  the  surface  of  the 
plaster,  &c.  of  rooms,  arches,  &c. 

Angle-brace,  in  carpentry,  timber 
fixed  to  the  two  extremities  of  a 
piece  of  quadrangular  framing, 
making  it  to  partake  of  the  form  of 
an  octagon 

Angle-bracket,  a  bracket  placed  in  the 
vertex  of  an  angle,  and  not  at  right 
angles  vrith  the  sides 

Angle-capital,  used  in  Ionic  capitals 
to  the  flank  columns  which  have 
their  volutes  placed  at  an  angle  of 
45°  with  the  planes  of  the  front 
and  returning  friezes 

Angle-float,  in  plastering,  a  float  made 
to  any  internal  angle  to  the  planes 
of  both  sides  of  a  room 

Angle-modiUion,  a  modillion  placed  in 
a  direction  parallel  to  a  diagonal 
drawn  through  a  cornice  at  its 
mitreing 

Angle  of  application,  the  angle  which 


AN6 


ANNULAR  ENGINE. 


ANT 


the  line  of  direction  of  a  power 
giyes  the  lever  it  acts  upon 

Angle  qf  incUnatUm,  the  angle  an  in- 
clined plane  makes  with  the  hori- 
zon 

Angle  qf  traction,  the  angle  which 
the  direction  of  a  power  makes 
with  the  inclined  plane 

Angular  perfpecthfCf  a  term  applied 
to  the  horizontal  lines,  both  of  the 
front  and  end  of  a  building,  con- 
verging to  vanishing  points,  and 
terminating  in  the  horizon ;  it  is 
lometimes  called  oblique  perspec- 
tive 

Anhydrous  eufyhuric  add,  pure  sul- 
phuric acid,  in  the  form  of  a  crys- 
talline solid 

Annealing,  the  process  of  softening 
and  restoring  the  malleability  of 
metals,  by  heating  and  allowing 
them  to  cool  very  slowly ;  and  by 
which  means  glass,  cast  iron,  and 
steel  may  be  united  to  other  sub- 
stances 

Annotto,  in  chemistry,  a  reddish-yel- 
low vegetable  dye,  obtained  from 
the  seeds  of  the  bixa  orellana,  and 
used  for  colouring  cheese 

Annular  engine,  a  direct-action  ma- 
rine engine,  having  two  concentric 
cylinders;  the  annular  space  is 
fitted  vdth  a  piston  which  is  at- 
tached to  a  T-shaped  cross-head 
by  two  piston-rods :  the  cross-head 
is  formed  by  two  plates  with  a  space 
between  for  the  connecting-rod  to 
vibrate,  and  the  lower  end  slides 
within  the  inner  cylinder,  and  is 
connected  to  the  crank.  This  ar- 
rangement has  been  patented  by 
Messrs.  Maudslay 

Annular  vault,  a  vaulted  roof  sup- 
ported on  circular  walls 

Annulated  eoAcmiM, those  clustered  to- 
gether or  joined  by  rings  or  bands 

Annulet,  in  architecture,  a  small 
square  member  in  the  Doric  capi- 
tal ;  also  the  name  of  a  small  flat 
moulding 

AntiP,  square  pilasters  terminating 
the  walls  of  a  temple:  when  a 
temple  had  no  portico  in  front,  two 
I      columns  were  made  to  intervene 

"^18 


between  the  antae,  and  the  aspect 
of  the  temple  was  said  to  be  in 
antia 

Ante»ehamber,  a  room  or  passage  to 
an  inner  chamber,  for  the  accom- 
modation  of  servants  and  persons 
in  waiting 

Ante'Ctgntuhan,  part  of  a  cloister  be- 
fore the  door  of  a  chapter-house 

Antefixa  (by  some  called  Greek  tiles)  ^ 
upright  ornamental  blocks  placed 
at  intervals  on  the  cornice  along 
the  side  of  a  roof,  to  conceal  or 
rather  terminate  the  ridges  formed 
by  the  overlapping  of  the  roof  tiles ; 
also  heads  of  lions,  &c.,  for  ^watcr 
spouts,  below  the  eaves  of  temples 

Antemural,  a  term  applied  to  the 
outward  wall  of  a  castle ;  or  that 
which  separates  a  presbytery  from 
a  choir;  also  to  a  biurbican  entrance 
before  a  castle 

Antepagmenta,  or  Antepagmentum, 
the  jamb  of  a  door-case 

Ante 'parallels,  in  geometry,  lines 
which  make  equal  angles  witb  two 
other  lines,  but  in  a  contrary  direc- 
tion 

Ante-portico,  a  term  sometimes  used 
to  denote  an  outer  porch  or  vesti- 
bule; the  prcpgkeum  in  classic 
architecture 

Awterides,  buttresses  for  strengthen- 
ing walls 

AntC'Solarium,  a  balcony  facing  the 
sun 

Ante»venna,  an  awning  or  projecting 
roof  of  wood-work ;  a  wooden  or 
pent-house  before  a  shop 

Anthepsa,  a  Grecian  vessel  used  for 
boiling  water  or  keeping  it  hot ;  a 
cooking  utensil 

Anthracite,  a  coal  not  bituminous 
found  principally  in  South  Wales 
and  in  the  United  States 

Antics,  in  architecture,  figures  of  men 
beasts,  &c.,  placed  as  ornaments  to 
buildings 

Anticum,  a  porch  before  a  door 

Antilia,  an  ancient  machine  similar 
to  the  modern  pump 

Antimensium,  a  portable  altar  or  con- 
secrated table,  used  as  a  substitute  I 
for  a  proper  altar  1 


ANT 


APOSTLES. 


API 


AfUimeter^  an  optical  mstraincnt  for 
measuring  angles 

Antimony,  a  metal  usually  found  in  a 
crude  state  combined  -with,  sulphur, 
of  a  bluish-white  colour,  crystal- 
line texture,  brittle,  and  easily  pul- 
verized. It  does  not  oxidate  at 
ordinary  temperatures  in  the  air, 
but,  when  heated,  it  bums  with  a 
light  flame,  producing  the  oxide; 
it  fuses  at  800^,  and  volatilizes  at  a 
white  heat 

Antimony  yellow,  a  preparation  of 
antimony,  of  a  deeper  colour  than 
Naples  yellow,  and  similar  in  its 
properties :  it  is  principally  used 
in  enamel  and  porcelain  painting, 
and  is  very  various  in  tint;  that 
of  a  bright  colour  is  not  affected 
by  foul  air,  although  blackened  by 
sugar  of  lead 

Antipagments,  ornaments  in  carved 
work  on  the  architrave,  jambs, 
posts,  or  puncheons  of  doors 

Antiquarium,  a  repository  for  antique 
monoments 

AntreUum,  a  small  cave  or  grotto; 
also  a  small  temple 

Antrum,  an  early  temple  for  Christian 
worship 

Antrum  iumdale,  a  sepulchral  cave  or 

grotto 

Antwerp  blue,  light  -  coloured,  and 
somewhat  brighter  than  Prussian 
blue,  or  ferro-prussiate  of  alumine, 
having  more  of  the  terrene  basis, 
but  all  the  other  qualities  of  that 
pigment,  except  its  extreme  depth. 
Haarlem  blue  is  a  similar  pigment 

Antwerp  hraum,  a  preparation  of 
asphaltuna  ground  in  strong  drying 
oil,  by  which  it  becomes  less  liable 
to  crack 

Anvil,  a  large  block  of  iron  with  a 
very  hard  smooth  horizontal  sur- 
face on  the  top,  in  which  there  is 
a  hole  at  one  end,  for  the  purpose 
of  inserting  various  tools,  and  a 
strong  steel  chisel,  on  which  a  piece 
of  iron  may  be  laid,  and  cut  through 
by  a  blow  with  a  hammer 

A-peek,  a  nautical  term  implying  that 
the  cable  is  hove  taut,  so  as  to  bring 
the  vessel  nearly  over  her  anchor  : 


19 


the  yards  are  a-^«eitwhen  they  arc 
topped  up  by  contrary  lifts 
Aperture,  an  opening  in  a  wall,  door« 

way,  or  window 
Apex,  the  top  or  highest  point  of  a 
cone,    mountain,   pyramid,  spire, 
roof,  &c. 
Apiary,  a  place  where  bees  are  kept 
Aplome,  a  mineral  of  a  deep  orange 
colour 

Apluitre,  in  early  naval  architecture, 
a  carved  tablet  fixed  on  the  ex- 
tremity of  a  ship's  head 

Apodyterium,a.  dressing-room  or  ante- 
room  to  a  bath  in  Roman  vUlas,  con- 
tiguous to  the  laeanieum 

Apophyge,  in  architecture,  that  part 
of  a  column  between  the  upper 
fillet  of  the  base  and  the  cylindrical 
shaft,  which  is  usually  curved  into 
it  by  a  concave  sweep  or  inverted 
cavetto 

Apostles  (the)  of  Jesus  Christ  were  his 
chief  disciples,  whom  he  invested 
with  his  authority,  filled  with  his 
spirit,  and  instructed  particularly 
in  his  doctrines  and  services :  they 
were  chosen  to  raise  the  edifice  of 
his  church;  and,  after  his  resurrec- 
tion, sent  into  all  the  world,  com- 
missioned to  preach,  to  baptize,  and 
to  work  miracles.  The  names  of 
the  twelve  were, — 1.  Peter.  2.  An- 
drew. 3.  John.  4.  Philip.  5.  James, 
major.  6.  Bartholomew.  7.  Thomas. 
8.  Matthew.  9.  Simon.  10.  Jud^. 
11.  James,  minor.  12.  Judas  Is- 
cariot.  The  last  betrayed  his  mas- 
ter, and  having  hanged  himself, 
Matthias  was  chosen  in  his  place 

Apotheca,  a  place  in  the  upper  part 
of  the  house,  in  which  the  Romans 
frequently  placed  their  wines  in 
earthen  amphorae ;  also  an  apothe- 
cary's shop,  a  cabinet,  storehouse, 
&c. 

Apothesis,  a  recess  on  the  south  sid^ 
of  the  chancel  of  a  church,  fitted 
up  with  shelves  for  books,  vest- 
ments,  &c. 

Apparatus,  a  term  denoting  a  com- 
plete set  of  instruments  belonging 
to  an  artist  or  a  mechanist 

Appaumie,  in  heraldry,  to  extend  the 


APP 


APPIAN  WAY. 


ARC 


palm  of  the  hand  and  the  thumb 
and  fingers  at  fall  length 

Appian  watf^  a  celebrated  road  lead- 
ing from  Rome  to  Brundusium :  so 
named  from  Appius  Claudius 

Appii  forum,  the  forum  built  by  Ap- 
pius, the  Roman  consul,  about  50 
miles  distant  from  Rome,  near  the 
modern  town  of  Pipemo,  on  the 
way  to  Naples.  The  uses  to  which 
the  Romans  applied  the  forum  were 
so  various,  that  it  is  not  easy  to  as- 
certain the  nature  of  the  building. 
Itmighthavebeen  a  place  for  thedis- 
tribution  of  justice,  or  for  holding  a 
market.  The*  Three  Taverns' were 
nearer  to  Rome  than  the  Appii 
forum,  as  Cicero  intimates,  who, 
in  going  from  Rome,  a  little  before 
he  came  to  the  forum  of  Appius, 
arrived  at  the  Three  Taverns;  so 
that  probably  the  chief  number  of 
Christians  waited  for  the  Apostle 
Paul  at  a  place  of  refreshment, 
while  some  of  their  number  went 
forward  to  meet  him  and  to  acquaint 
him  with  their  expectation  of  seeing 
him  among  them,  and  for  which 
they  respectfully  waited  his  coming. 
— Calmet, 

Apple-tree,  a  wood  generally  hard 
and  close,  and  of  reddish-brown 
tints,  used  commonly  in  Tunbridge 
turnery,  &c. 

Apricot'tree,  a  native  wood  of  Ar- 
.  menia,  used  by  the  French  in 
turnery 

Apron,  the  sill  or  lower  part  of  a  win- 
dow ;  a  platform  or  flooring  of  plank 
raised  at  the  entrance  of  a  dock :  in 
naval  architecture,  a  piece  of  curved 
timber  fixed  behind  the  lower  part 
of  the  stem  of  a  ship 

Apsis,  the  east  end  of  a  church  or 
chancel;  sometimes  applied  to  a 
canopy  over  an  altar ;  also  to  a 
circle  about  a  star  or  planet 

Apsis  gradata,  a  bishop's  throne  in 
cathedral  churches 

Apyrous,  a  chemical  term  applied  to 
refractory  bodies  which  resist  heat 

Aquafortis,  in  chemistry,  nitric  acid 
diluted ;  the  more  concentrated  is 
named  spirit  of  nitre 

20 


Aquamaie,  a  holy-water  baain 

Aqua  regia,  nitro -muriatic  acid;  a 
compound  of  two  parts  nitric  acid 
and  one  part  muriatic  add 

Aquatinta,  in  the  arts,  engraving 
which  resembles  drawings  in  Indian 
ink 

Aqua  tqfano,  a  poisonous  liquor 

Aqueduct,  a  conduit  for  water :  a  con- 
struction of  stone  or  timber,  built 
on  uneven  ground,  to  preserve  the 
level  of  water,  and  convey  it  by  a 
canal  from  one  place  to  another 

Aquemola,  a  water-mill 

Aquila,  a  reading-desk,  so  called  from 
its  shape  being  that  of  an  eagle 
with  extended  wings,  supported  by 
a  pedestal 

Arabesque,  generally  applied  to  a  style 
of  ornament  for  pilasters,  friezes, 
&c.,  as  those  painted  by  Rafaelle 
in  the  Vatican 

ArabO'tedesco,  a  term  applied  to  the 
Moorish  style  of  buildings  in  Spain, 
&c. 

Ara  dignitatis,  an  altar  at  which  none 
butthe  highest  ecclesiastics  perform 
divine  rites 

AriBOstyle,  in  architecture,  the  g^at. 
est  interval  or  distance  which  can 
be  made  between  columns,  that  is, 
eight  modules  or  four  diameters ; 
also  a  species  of  temple  which  has 
its  columns  placed  widely  asunder 

Arbor,  a  spindle  or  axis  upon  which  a 
ring  or  wheel  is  turned  in  a  lathe 

Arbor  Diarus,  in  chemistry,  crystals 
formed  by  the  combination  of  sil- 
ver and  mercury 

Arbores,  brass  branches  for  lights  sua- 
pended  from  ceilings 

Arboretum,  a  grove  of  trees  in  a  park, 
pleasure-ground,  or  garden 

Arbor  vittB,  a  tree  which  attains  to  a 
height  of  from  40  to  50  feet ;  its 
wood  is  of  a  reddish  colour,  very 
light,  soft,  and  fine-grained,  and  is 
much  used  in  house  carpentry 

Arc,  in  geometry,  part  of  the  circum- 
ference of  a  circle,  or  any  curve 
lying  between  two  points ;  a  bow 
vault,  or  arch 

Area,  a  place  in  a  vaulted  chamber 
for  sepulchral  purposes;  an  exca- 


ARC 


ARCADE. 


ARC 


Tation  before  the  basement  story 
of  a  house ;  an  enclosed  space ;  a 
chest  in  which  the  Romans  depo- 
sited their  money:  the  word  is  also 
nsed  to  signify  a  beam  of  wood 
which  has  a  groove  or  channel  hol- 
lowed in  it  from  one  end  to  the 
other 
Aireadey  a  series  iA  recesses  with 
arched  ceilings  or  soffits ;  a  covered 
passage;  in  modem  appliances,  a 
vaalted  avenue,  nowr  much  in  vogue, 
moreparticularly  in  Paris.  Arcades, 
though  less  magnificent  than  colon- 
nades, are  of  extraordinary  beaoty 
when  well  contrived,  affording  shade 
from  the  sun  and  shelter  from  the 
rain.  Though  not  so  magnificent 
as  colonnades,  they  are  stronger, 
more  solid,  and  less  expensive. 
They  are  proper  for  triumphal  en- 
trances, gates  of  (uties,  of  palaces, 
of  gardens,  and  of  parks;  for  public 
squares,  markets,  or  large  courts  in 
general,  and  for  all  apertures  that 
require  an  extraordinary  width. 

Their  ornaments.— The  piers 
of  arcades  may  be  decorated  with 
cdumns,  pilasters,  niches,  and  aper- 
tures of  different  forms.  The  arch 
itself  may  be  turned  either  with 
rock-worked  or  plain  rustic  arch 
stones  or  voussoirs,  or  with  an 
archivolt  properly  moulded.  The 
keystone  is  generally  carved  in  the 
form  of  a  console,  or  sculptured 
with  some  head,  or  the  Hke.  The 
archivolt  springs  from  an  impost  or 
plat-band,  or  sometimes  from  co- 
lumns ;  but  this  is  not  to  be  prac- 
tised except  in  cases  of  the  most 
'  nrgent  nature,  for  it  makes  neither 
substantial  nor  beautiful  work. 

In  arches  that  arc  of  large  dimen- 
sions, the  keystone  should  never  be 
omitted ;  its  carving,  however,  may 
be  dispensed  with,  if  expense  be  an 
object.  When  the  piers  are  deco- 
rated vnth  disengaged  columns,  the 
enUbUituie  must  break  round  over 
the  cohmins;  and  the  columns, 
whether  engaged  or  not,  should 
stand  either  on  a  pedestal  or  high 
plinth,  by  which  means  they  will 


not  only  be  kept  dry,  bat  their 
bases  will  likewise  be  protected 
from  accidental  damage. — ^Arches 
must  always  rise  from  an  impost  or 
a  plat-band;  and  if  there  be  no 
keystone  to  the  archivolt,  its  sum- 
mit should  be  kept  down  from  the 
under  side  of  the  architrave  of  the 
accompanying  order,  at  least  half 
the  distance  that  it  woald  be,  were 
a  keystone  employed,  in  order 
that  the  disagreeable  appearance  of 
the  acute  angle  which  it  would 
otherwise  form  with  the  architrave 
may  be  avoided. 

Thbib  proportions.  —  The 
height  of  arches  to  the  under  side 
of  their  crowns  should  not  exceed 
twice  their  clear  width,  nor  should 
it  be  much  less;  the  piers  not 
less  than  one-third  the  breadth  of 
the  arch,  nor  more  than  two-thirds; 
but  the  piers  at  the  angles  should 
be  wider  than  the  other  piers  by 
one-half  or  one-fourth  at  least 

Arc€R,  in  Roman  architecture,  the 
gutters  of  the  cavedium 

Arc-boutantt  a  kind  of  arched  but- 
tress formed  of  a  fiat  arch,  or  part 
of  an  arch,  and  abutting  against  the 
feet  or  sides  (tf  another  arch  or 
vault,  to  support  them,  and  prevent 
them  from  bursting  or  giving  way 

ArcettOf  in  mediaeval  architecture,  a 
cheese-room 

Arch,  the  curved  part  of  a  building, 
supported  at  its  extremities  only, 
and  concave  towards  the  earth ;  a 
vaulted  roof,  or  dome,  constructed 
either  with  bricks,  stone,  or  other 
materials :  the  arch  of  a  bridge  is 
formed  of  segments  of  a  circle, 
elliptical  or  catenarian;  in  Christian 
architecture,  arches  display  twenty, 
two  varieties  of  form.  —  Arches 
are  used  in  large  intercolumni- 
atlons  of  spacious  buildings;  in 
porticoes,  both  within  and  without 
temples;  in  public  halls,  as  ceil- 
ings,  the  courts  of  palaces,  cloisters, 
theatres,  and  amphitheatres  :  they 
also  are  used  to  cover  the  cellars  in 
the  foundations  of  houses  and  pow- 
der-magazines ;  also  as  buttresses 


21 


1 


ARC 


and  counterforts,  to  support  large 
walls   laid    deep    in    the    earth; 
for  triumphal  arches,  gates,  win- 
dows, &c. ;  and,  above  all,  for  the 
foundations  of  bridges  and  aque- 
ducts :  they  are  supported  by  piers, 
abutments,  imposts,  &c. — ^Arches 
are  of  several  kinds,  circular,  ellip- 
tical, cycloidal,  catenarian,  &c.,  ac- 
cording as  their  curve  is  in  the  form 
of  a  circle,  ellipse,  cycloid,  cate- 
nary, &c. — ^Arches  are  to  be  found 
in  the  Greek  theatres,  stadia,  and 
gymnasia,  some  of  them  erected 
probably  400  years  before  Christ. 
The  most  ancient  arches  of  which 
we  have  correct  data  are  those  of 
the  cloacs  at  Rome.   The  emperor 
Hadrian  threw  a  bridge  over  the 
Cephisus,  between  the  territories  of 
Attica  and  Eleusis,  on  the  most 
frequented  road  of  Greece. 
Jrch  (the  theory  of).   This  important 
subject  has  exercised  the  talents 
and  ingenuity  of  some  of  the  great- 
est   mathematicians    in     modem 
times,  and  many  different  solutions 
have  been  given  to  the  various  pro- 
blems connected  with  it;  but,  as 
the  greater  part  of  them  are  founded 
on  suppositions  that  have  no  exist- 
ence whatever  either  in  nature  or 
practice,  they  have  had  a  tendency 
rather  to  mislead  than  direct  those 
who  are  engaged  in  the  operations 
of  bridge-building.     Dr.  Olinthus 
Gregory,  in  the  preface  to  his  ex- 
cellent work  on  Mechanics,  states, 
that  '^  theoretical  and  practical  men 
will  most  effectually  promote  their 
mutual  interests,  not  by  affecting 
to  despise  each  other,  but  by  blend- 
ing their  efforts ;  and  further,  that 
an  essential  service  will  be  done  to 
mechanical  science,  by  endeavour- 
ing to  make  all  the  scattered  rays 
of  light  they  have  separately  thrown 
upon  this  region  of  human  know- 
ledge   converge    to    one    point." 
Gauthey,  speaking  of  the  theory  of 
La  Hire,  observes  that  such  analy. 
tical  researches  are  founded  on  hy- 
potheses which  every  day's  experi- 
enoe  contradicts.  The  following  are 

22 


ARCH.  ARC 

the  principal  writers  on  the  equilib- 
rium of  the  arch.   In  1691,  the  ce- 
lebrated mathematicians,  Leibnitz, 
Huygens,  James  and  John    Ber- 
nouiUi,  solved  the  problem  of  the 
catenary  curve:  it  was  soon  perceiy- 
ed  that  this  was  precisely  the  curve 
of  that  should  be  given  to  an  arch 
which  the  materials  were  infinitely  i 
small  and  of  equal  weight,  in  order ' 
that  all  its  parts  may  be  in  equili- 
brium.     In    the    '  Philosophical 
Transactions'  for  the  year  1697,  it ' 
is  stated  that  David  Gregory-  first 
noticed  this  identity;  but  his  mode 
of  argument,  though  sufficiently , 
rigorous,  appears  not  to  be  so  per- 
spicuous as  could  be  desired.     In 
one  of  the  posthumous  works  of 
James  Bemouilli,  two  direct  solu- 
tions of  this  problem  are  given, 
founded  on  the  different  modes  of 
viewing  the  action  of  the  voussoirs : 
the  first  is  clear,  simple,  and  precise, 
and  easily  leads  to  the  equation  of 
the  curve,  which  he  shows  to  be 
the  catenary  inverted ;  the  second 
requires  a  little  correction,  which 
Cramer,  the  editor  of  his  works, 
has   pointed  out.      In  1695,    La 
Hire,  in  his  *  Treatise  on  Mecha- 
nics,' laid  down,  from  the  theory  of 
the  wedge,  the  proportion  accord- 
ing to  which  the  absolute  weight 
of  the  materials  of  masonry  ought 
to  be  increased  from  the  keystone 
to  the  springing  in  a  semicircular 
arch.    The  historian  of  the  Ac*ade- 
my  of  Sciences  relates,  in  the  vo- 
lume for  the  year  1 704,  that  Parent 
determined  on  the  same  principle, 
but  only  by  points,  the  figure  of  the 
extrados  of  an  arch,  the  intrados 
being  a  semicircle,  and  found  the 
force  or  thrust  of  a  similar  arch 
against  the  piers.   In  the  *  Memoirs 
of  the  Academy  of  Sciences'  for  the 
year  1712,  La  Hire  gave  an  inves- 
tigation of  the  thrusts  in  arches 
under  a  point  of  view  suggested  by 
his  own  experiments :  he  supposed 
that  arches,  the  piers  of  which  had 
not  solidity  enough  to  resist  the 
thrust,  split  towaids  the  haunches 


ARC 


ARCH. 


ABC 


at  an  elevation  of  about  45  degrees 
above  the  spring^ings  or  impost;  he 
consequently   reg^arded  the  upper 
part  of  the  arch  as  a  wedge  that 
tends  to  separate  or  overturn  the 
abutments,  and  determined,  on  the 
theory  of  the  ^wedge  and  the  lever, 
the  dimensions  vehich  they  ought 
to  have  to  resist  this  single  effort. 
Couplet,  in  a  memoir  composed  of 
two  parts,  the  first  of  which  was 
printed  in  the  volume  of  the  Aca- 
demy for  1729,  treats  of  the  thrusts 
of  arches  and  the  thickness  of  the 
voussoirs,  by  considering  the  mate- 
rials infinitely  small,  and  capable  of 
sUding  over  each  other  without  any 
pressure  or  friction.     But,  as  this 
hypothesis  is  not  exactly  conform- 
able to  experiment,  the  2nd  part  of 
the  memoir,  printed  in  the  volume 
for  1730,  resumes  the  question  by 
supposing  that  the  materials  have 
not  the  power  of  sliding  over  each 
other,  but  that  they  can  raise  them- 
selves and  separate  by  minute  rota- 
tory motions.    It  cannot,  however, 
be  said    that  Couplet  has  added 
materially  to  the  theories  of  La 
Hire  and  Parent,  and  none  of  them 
treated  the  subject,  either  in  theory 
and  practice,  in  such  a  satisfactory 
manner  as  "was  afterwards  done  by 
Coulomb.     S  ubsequently  a  memoir 
was  pubhshed  by  Bouguer  on  the 
curve  lines  that  are  most  proper 
for  the   formation    of  the  arches 
of  domes.    He  considers  that  there 
may  be  an  infinite  number  of  curve 
lines  employed   for   this  purpose, 
and  points  out  the  mode  of  select- 
ing them.     He  lays  it  down  uni- 
formly that  the  voussoirs  have  their 
surfaces  infinitely  smooth,  and  es- 
tablishes, on  this  hypothesis,  the 
conditions  of  equilibrium  in  each 
horizontal  course  of  the  dome,  but 
has  not  given  any  method  of  inves- 
tigating the  thrusts   of  arches  of 
this  kind,    nor  of  the  forces  that 
act  upon  the  masonry  when  the 
generating   curve   is  subjected  to 
given  conditions.     In  1 7  70,  Bossut 
gave  investigations  of  arches  of  the 

23 


different  kinds,  in  two  memoirs, 
which  were  printed  among  those 
of  the  Academy  of  Sciences  for  the 
years  1774  and  1776:  he  appears 
to  have  been  engaged  in  tUs  in 
consequence  of  some  disputes  con- 
cerning the  dome  of  the  French 
Pantheon,  begun  by  the  celebrated 
architect  Soufflot,  and  finished  from 
his  designs.  In  1772,  Dr.  Hntton 
published  his  principles  of  bridges, 
in  which  he  investigated  the  form 
of  curves  for  the  intrados  of  an 
arch,  the  extrados  being  given,  and 
vice  versa.  He  set  out  by  develop- 
ing the  properties  of  the  equili- 
brated  polygon,  which  is  extremely 
useful  in  the  equilibrium  of  struc- 
tures. Mr.  Attwood  has  written  a 
dissertation  on  the  construction  of 
arches  on  the  same  principles  as  La 
Hire. 

Archt  in  architecture,  a  Concave  struc- 
ture raised  or  turned  upon  a  mould, 
called  the  centering,  in  form  of  the 
arc  of  a  curve,  and  serving  as  the 
inward  support  of  some  superstruc- 
ture. Sir  Henry  Wotton  says,  **  An 
arch  is  nothing  but  a  narrow  or 
contracted  vault ;  and  a  vault  is  a 
dilated  arch.'' 

Archf  in  geometry,  a  part  of  any 
curved  Une,  as  of  a  circle  or  ellipsis 

Archt  in  masonry,  a  part  of  a  building 
suspended  over  a  hollow,  and  con- 
cave towards  the  area  of  the  hollow : 
the  top  of  the  wall  or  walls  which 
receives  the  first  arch-stones  is 
technically  called  the  abutment  or 
springing 

Jrchf  in  mining,  a  piece  of  ground  left 
unworked 

Arch-buttresSf  a  piece  of  insulated 
masonry  usually  named  a  flying- 
buttress,  extending  from  the  cleres- 
tory of  a  church  and  over  the  roof 
of  its  aisle,  where  it  rests  on  the 
buttress  of  the  outer  wall 

Arch  ofequilibrationf  that  which  is  in 
equilibrium  in  all  its  parts,  having 
no  tendency  to  break  in  one  part 
more  than  in  another 

Arch,  triumphalt  a  building  of  which 
an  arch  is  the  principal  feature, 


ARC 


ARCHITECTURE. 


ARCi 


usually  raised  to  commemorate 
some  great  achievement 

Jrchaohgy,  the  study  of  ancient  art, 
but  more  particularly  that  of  the 
middle  ages 

'  Arched,  in  mining :  the  roads  in  a 
mine,  when  built  with  stones  or 

'  bricks,  are  generally  arched  level 
drifts 

Archeion,  a  recess  in  a  Grecian  tem- 
ple, for  the  reception  of  the  trea- 
sures of  the  deity  to  whom  the 
temple  was  dedicated 

Archeiouy  in  Athens,  the  oiBce  in 
which  the  decrees  of  the  people 
and  other  state  documents  were 
preserved 

ArchetuSf  a  saw  for  cutting  stones : 
Muratori  used  the  term  for  a  crane 
or  pulley  for  raising  stones  to  the 
upper  part  of  a  building 

Archimedean  screw,  a  machine  in- 
vented by  Archimedes  for  raising 
water ;  also  now  applied  to  propel 
vessels  through  water 

Architect,  a  person  skilled  in  the  art 
of  building;  one  who  forms,  plans, 
and  designs  for  edifices,  conducts 
the  work,  and  directs  the  secondary 
artificers  employed ;  and  whose 
emoluments  are  generally  5  per 
cent,  on  the  amount  of  money  ex- 
pended 

Architecture,  a  science  applicable  to 
the  art  of  constructing  domestic, 
ecclesiastical,  municipal,  palatial, 
or  other  buildings,  and  the  adorn- 
ment of  the  same  according  to  the 
rules  of  the  several  orders,  Doric, 
Ionic,  and  Corinthian,  also  the  Tus- 
can, and  Composite,  from  Roman 
models,  or  other  styles,  each  for  its 
purpose,  such  as  is  usually  called 
Gothic  architecture,  and  modes 
subservient  to  climate  and  fashion, 
or  caprice.  "Architecture,"  says 
Palladio,  "being  grounded  upon 
rules  taken  from  the  imitation  of 
Nature,  admits  of  nothing  that  is 
contrary  or  foreign  to  that  order 
which  Natore  has  prescribed  to  all 
things.  An  architect  is  not  re- 
strained from  departing  sometimes 
from  common  methods  or  usage, 

24 


provided  such  variation  be  agree- 
able and  natural." 

The  public  at  large  has  a  claim 
over  the  architecture  of  a  coun- 
try. It  is  common  property,  in- 
asmuch as  it  involves  the  national 
taste  and  character;  and  no  man 
has  a  right  to  pass  off  his  own 
barbarous  inventions  as  the  na- 
tional taste,  and  to  hand  down  to 
posterity  his  own  ignorance  and  dis- 
grace to  become  a  satire  and  a  libel 
on  the  knowledge  and  taste  of  his 
age.  There  is  perhaps  no  subject 
on  which  persons  are  more  apt  to 
differ  in  their  opinions  than  on  the 
beauty  of  a  building.  In  archi- 
tecture the  creative  powerof  Nature 
herself  is  the  model  imitated.  It 
is  an  art  which  appeals  directly  to 
the  understanding,  and  has  not  the 
means  of  flattering  the  senses  in 
the  same  way  as  the  sister  arts: 
hence  its  productions  are  not  uni- 
versally appreciated.  The  beautiful 
models  of  Nature,  however,  are  the 
index  and  guide  of  the  painter  and 
sculptor :  a  successful  imitation  of 
these  models,  even  without  an  ad- 
vance on  the  part  of  the  artist 
towards  those  higher  intellectual 
beauties  which  distinguish  the  his- 
torical painter,  is  capable  of  affecting 
us  with  very  agreeable  sensations. 
The  object  of  an  artist's  inquiry  is 
not  so  much  to  investigate  meta- 
physically the  cause  of  beauty  in 
the  productions  of  his  art,  as  to 
study  the  effects  that  flow  from 
those  which  by  the  common  con- 
sent of  ages  are  esteemed  beautiful, 
and  thus  shorten  his  road  by  an  fl 
priori  method.  It  is  in  this  way 
that  he  will  more  readily  obtain 
information  on  those  qualities  which 
act  on  the  understanding  and  ex- 
cite our  affections  by  means  of  the 
beautiful  result  they  exhibit.  These 
qualities  may  be  classed  as  fol- 
lows: 

Magnitude  and  solidity,  as 
qualities  which  affect  the  eye. 

Order  and  harmony,  as  qual^' 
ties  which  affect  the  understanding. 


ARC 


ARCHITECTURE. 


ARC 


Richness  and  simplicity,  as 
qualities  which  excite  the  affec- 
tions,— ^in  which  taste  is  the  prin- 
cipal guide. 

These  qualities  answer  to  the 
three  divisions  which  those  who 
haye  written  on  architecture  have 
usually  adopted,  namely — 

Construction,  in  which  the 
chief  requisites  are  solidity  and 
strength. 

Design  oh  disposition,  in 
which  the  principal  requisites  are 
order  and  harmony. 

Decoration,  whose  requisites 
are  richness  or  simplicity,  according 
to  the  nature  of  the  composition. 

That  there  are,  however,  many 
other  circumstances  which  tend  to 
the  production  of  an  agreeable  and 
beautiful  result,  is  sufficiently  ob- 
vious: one  of  them  should  be  more 
particularly  noticed,  because  there 
can  be  no  doubt  of  its  influence  in 
the  excitement  of  our  admiration 
of  the  splendid  monuments  of  Gre- 
cian art ;  it  is  an  association  with 
the  times  and  countries  which  are 
most  hallowed  in  our  imagination. 
It  is  difficult  for  us  to  see  them, 
even  in  their  modem  copies,  with- 
out feeling  them  operate  upon  our 
minds,  as  relics  of  those  polished 
nations  where  they  first  arose,  and 
of  that  great  people  by  whom  they 
were  afterwards  borrowed. 

The  business  of  an  architect  re- 
quires him  rather  to  be  a  learned 
judge  than  a  skilful  operator ;  and 
when  he  knows  how  to  direct  and 
instruct  others  with  precision,  to 
examine,  judge,  and  value  their 
performances  vnth  masterly  accu- 
racy, he  may  truly  be  said  to  have 
acquired  all  that  most  men  can  ac- 
quire :  there  are  but  few  instances 
of  such  prodigies  as  Michael  An- 
gelo  Buonarotti,  who  was  at  once 
the  first  architect,  painter,  geome- 
trician, anatomist,  and  sculptor  of 
his  time. 

Vitruvius  furthermore  observes, 
that  an  art  enriched  with  such 
variety  of  knowledge  is  only  to  be 


learned  by  long  and  constant  appli- 
cation ;  and  advises  his  contempo- 
raries never  to  assume  the  title  of 
architects  till  they  are  perfect  mas- 
ters of  their  own  profession,  and  of 
the  arts  and  sciences  vrith  which  it 
is  connected ;  a  caution  that  even 
in  the  present  times  may  perhaps 
not  be  unnecessary. 
Architecture  (the  application  of  the 
orders  of).  Among  the  ancients, 
the  use  of  the  orders  was  very  fre- 
quent ;  many  parts  of  their  cities 
were  provided  with  spacious  porti- 
coes, their  temples  were  surround- 
ed vrith  colonnades,  and  their  the- 
atres, baths,  basiUcsB,  triumphal 
arches,  mausolea,  bridges,  and  other 
public  buildings  were  profusely 
enriched  vrith  columns;  as  were 
likewise  the  courts,  vestibules,  and 
halls  of  their  private  villas  and 
houses. 

In  pure  architecture,  says  A.  W. 
Pugin,the  smallest  detailshouldhave 
a  meaning  or  serve  a  purpose ;  and 
even  the  construction  itself  should 
vary  with  the  material  employed,  and 
thedesigns  should  be  adapted  to  the 
material  in  which  they  are  executed. 

Strange  as  it  may  appear  at  first 
sight,  it  is  in  pointed  architecture 
alone  that  these  great  principles 
have  been  carried  out :  we  may  be 
enabled  to  illustrate  them  from  the 
vast  cathedral  to  the  simplest  erec- 
tion. Moreover,  the  architects  of 
the  middle  ages  were  the  first  who 
turned  the  natural  properties  of 
the  various  materials  to  their  fuU 
account,  and  made  their  mechanism 
a  vehicle  for  their  art.  The  won- 
derful strength  and  solidity  of  their 
buildings  are  the  result,  not  of  quan- 
tity  or  size  of  the  stones  employed, 
but  of  the  art  of  their  disposition. 


On  the  following  page  is  a  synopsis 
of  the  proportions  of  the  orders, 
and  of  the  various  examples  of 
each,  compiled  expressly  by  Mr. 
W.  H.  Leeds  for  Pugin's  edition  of 
Normand's  'Parallel  of  the  Or- 
ders.* 


25 


ARC 


ARCHITECTURE. 


Names  of  the  Order*. 


TUSCAN. 

Palladio 

Scamoxii 

Serlio      *...... 

VignoU  . 

DORIC. 
Parthenon  at  Athens     .    . 
Temple  of  Theseus,  do.      . 
Great  Temple  at  Psstum  . 
Temple  of  Apollo  at  Delos 
Portico  of  Philip,       do.    . 
Temple  at  Corinth    .    .    . 
PropylsBum  at  Athens   .    . 
Portico  of  Augustus,  do.    . 
Theatre  of  Marcellus,  Rome 
Doric  Order  at  Albano  .    . 
Baths  of  Diocletian  .    .    . 

PaUadio 

Scamozzi     ■    •    .    .    *    • 

Vignola 

Viola 

Delonne 


IONIC. 
Temple  on  the  Ilissus  .... 
Temple  of  Minerva  Poliaa,  Athens 
Temple  of  Erechtheus,  Athens  . 
Temple  of  Fortuna  Virilis  .  .  . 
Theatre  of  Marcellus     .... 

Baths  of  Diocletian 

Palladio 

Scamozzi 

Vignola 

Serlio 

Alberti 

CORINTHIAN. 
Lftntem  of  Demosthenes,  Athens 
Temple  of  Jupiter  Olympius,  do. 
Incantada  at  Salonica    .... 
Arch  of  Theseus,  Athens    .    .    . 

Templeof  Jupiter  Stator,  Rome  . 
Temple  of  Jupiter  Tonans  .  .  . 
Portico  of  the  Pantheon  .  .  . 
Interior  of  the  Pantheon    .    .    . 

Forum  of  Nerva 

Temple  of  Antoninus  and  Faustina 


Nero's  Frontispiece 
Arch  of  Constantine  .    .    . 
Temple  of  Mars  the  Avenger 
Basilica  of  Aptoninus    .    . 
Temple  of  the  Sibyl,  Tivoli 
Palladio  ....... 

Scamozzi     ...... 

Vignola  ....,,. 

Serlio 

Alberti 


COMPOSITE. 

Arch  of  Titus 

Arch  of  Septimiua  Severus 
Baths  of  Diocletian  .    .    . 

Palladio 

Scamozzi 

Vignola 

Caryatides   of  the  Temple 
Pandrosus 


?'} 


Base. 


i 

0 
0 
0 
0 


a  u 

1  0 

1  0 

1  0 

1  0 


0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 

0 
0 
0 
0 


] 
1 
1 
1 
1 

1 

0 
0 

1 
1 
1 

0 
0 
0 
0 
0 

1 

0 
0 
0 
0 
0 
0 
0 


0 
0 
0 
0 
0 

0 
25 

oi 

0 

0 
22 
22 
20 
20^ 
22| 

8* 
21 
25 
23 

20 
224 
24 
23i 


0 
0 
0 


0  24 

0  204 

0  24 


0 
0 
0 
0 
0 
0 
0 

0 

0 
0 
0 
0 
0 


0  23 

0  164 


0 
0 
0 
0 
0 


0  23 
0  20 

0  82 

1  14 
1     0 

1     0 


Column. 


I  "S     • 

^  a  u 

7  0 

7  1 

6  0 

7  0 


0 
0 
0 
0 


5     10 
5     1     0 

4  0  16 

5  0  25 

6  0  20 
8     0  10 

1     0 

0  0 

1  18 
1  0 
0    0 


5 
6 
7 
7 
8 
8 
8 
8 
8 
8 


f 

0 
0 
0 


0 
0 
0 
0 
0 


8 

0 

0 

9 

0 

9 

0 

8 

2i 

9 

0 

8 

0 

9 

0 

8 

15 

9 

0 

0 

7 

1 

0 

8 

0 

0 

10    0  0 

9    1  15 

0  15 

1  0 
0  (^ 

10    0  15 

9    1  I6i 

9    1  44 


9 

9 

10 


9    1    Oi 
10     0    0 

9    1    7 


10     0  111 

9    0  25 

1     0 

0 

0 

0 

0 


9 

10 

10 

9 

9 


0 
0 
0 
0 


10 
9 


0  6 

1  10 
10    0  29i 

10   0   a 

9     1   15 
0    0 


10 
6 


0    0 


Capital. 


€  a 
0  1 
0  1 
0  1 
0  1 


0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 


Q. 
0 
0 
0 
0 


0    0  28 


1     0 
1     2| 
0  284 

0  16 

0  25i 
0  23 
0  23 

1  a* 


0 
0 
0 
0 
0 
0 
0 


1  9k 
1  13| 
1  10 

0  29 

1     14 
1     1 
1     1 
0204 

1  o| 

1     0 

1  14 


0  24 

0  27 

0  11 
0  16 
0    6i 
0  10 

0   7* 

0  12i 
0  18 
0    8] 

0  16 

0    61 


0 
0 
0 
0 
0 
0 
0 
0 


9k 

9k 

0 

0 

0 

0 

0 

0 


Archi- 
trave. 


Frieze. 


0  Hi 

0  54 

0  11 
0  0 
0  0 
0    0 

0   0  27 


I   -g    ^ 

"o  a  P. 
5 

0 

25 


0 
0 
0 
0 

0 
0 
0 
0 
0 
0 


0 
0 
0 
0 
0 
0 
0 
0 

0 
0 

• 

0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 


144 

20 

"4 

20 
9 

Id 


1 

0 
2 
0 
5 
0 
0 
0 

35 

214 

84 
13 

4 

6 

15 

74 
0 

0 

21 

111 
164 

124 

134 

124 
12| 
12 
14 

134 
144 

15 

91 
134 

0 

8 
12 
15 

0 

0 

16 

15 

144 

10 

9 
15 


't3  a 

0  0  sc 

0  1    9 

0  10 

0  15 


i 


0  1  I9i 

0  1  25^ 

0  1  8( 

0  1  7 

0  1  14 


1  161 

1  is; 

I  15; 

1  15; 

1  15 

1  15 

0     1  15 

0     1  15 


0    1  19 

0     1  184 


0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

• 

0 

o 
o 

0 
0 
0 
0 

0 
0 
0 
0 
0 
0 


ii 

0  28 

0  27 

0  38 

1  15 

0  224 

1     0 


1   04 
0274 

1  13^ 

1  10 

1  134 

1  13 
1    94 

1  IS 

1  15 

1  10) 

1  Ui 

1  10 

.       . 

1  10 
1    9k 

0  234 

1     2 
1  15 

1  7 
1   0 

1   14 

0  25i 

1  14 
1     0 

1     U 

I  15 


0   1  254 


26 


IRC 


ARCHITECTURE. 


ARC 


iCornice. 


Entabla- 
ture. 


Interco- 
luxnniation. 


'at 

1  13^ 
1  U 
1     0 
1  10 

t  0  S6 

0  0  25^ 

•  e  28 

0  1     74 

0  0  25 


61 

5 
16 

8 
17 
15 
10 
10 

2 

74 

m 

0 
16 
16 
13 

2 
10 

20 
18 
13i 
164 

Of 
I6i 
24 

2U 
254 

224 

m 

284 


3 

174 

19 

0 

9 
10 


1  0  3 

1  0  Sk 

•  I  SI 

t  1  90 

0  1  I6f 

1  0  0 

10  0 


a  -6 

eS  o       • 

;g  g  ^ 

1  1  U4 

I  1  224 

1  1    0 

1  1  10 

s  0    o 

s  0  11 

1  1  12 

2  0    44 

1  1   18 


Diameter  of 
column. 


S 
2 
3 
2 
3 
2 


1 
1 

S 
1 
2 
S 
1 
1 


1  23f 
1  20 

0  3 

1  23 
0     7 

0  0 

1  25 
1  25 


2     O  18 
2     O   17i 


2 
2 
1 
1 
1 
2 
1 
1 

2 

1 
2 

2 
2 
& 
2 

2 
2 
2 
2 
2 


251 


O 
O 
1    18 

1    19 
1    25 

0  15 

o  244 

1  10 

o  204 

1    27 
O     7i 

0  14 

1  6* 
O    111 

O   I6i 

O   15i 
O  284 

o  164 

O  26| 

o  234 


1 
1 
2 
2 
1 
1 

3 
3 
3 
3 
1 
3 


1  124 

1  24 

0  3 

1  0 
1  16 
1  10 

1     2 

o  19 
o  194 

0  0 

1  27 
1    0 

1  254 


3 

4 


3 
1 
2 


o       • 


0  20 

1  6 
O    10 

0  25 

1  5 
O    15 


1    1 
O 


2      O  15 


0  0 

1  20 
1      5 


2     O     74 


206 

3  0     0 

8  0  24 

•  ■          • 

115 

1  1     34 

2  0  15 

2  0  24 

•  •     . 

1  1     14 

1  1     0 

•  •     • 

1  0  284 

1  1  io| 

2  0  14 

3  0  0 
3  0  0 
2  0  20 


•  .  * 

•  •  • 

•  •  « 

■  •  • 

•  ■  • 

•  •  • 

I  •  • 


feet,    inches. 


6  1 

6  1 

7  0*03 
•  .    • 

3  5-10 


405 


1  9*4 

2  9'4 

2  3-8 

3  3 


1        3 

3  11*3 
8  5'  9" 


4 
4 
4 
3 
3 
4 

• 
3 
5 

• 
3 


10ft 
11 

sft 

6 


11 


1 

44 


3 

3 


lOft 
Oft 


27 


Architecture,  Naval,  the  art  of  con- 
strocting  ships  and  Teasels  to  float 
on  the  waters.    Naval  architecture 
has  suffered  more  than  most  other 
sciences  by  the  arbitrary  systems 
of  those  interested  in  its  improve- 
ment. Disregarding  the  fundamen- 
tal principles  of  all  floating  bodies, 
and  too  hastily  giving  up  as  hope- 
less the  attainment  of  a  theory 
combining  experiment  vnth  esta- 
blished scientific  principleSi  they 
have   contented  themselves  with 
ingeniously  inventing  mechanical 
methods  of  forming  the  designs  of 
ships'  bodies,  which  they  did  not 
even  pretend  to  prove  had  any 
connexion  with  the  properties  of 
the  machine  necessary  to  insure 
the  qualities  conducive  to  its  in- 
tended use.     For  instance,  some 
invented  methods  of  forming  ships' 
bodies  of  arcs  of  circles ;  others,  of 
arcs  of  ellipses,  parabolas,  or  of 
whatever  curve  they  might  arbi- 
trarily assume.    They  did  not  at- 
tempt to  show  that  these  curves 
possessed  any  property  which  would 
render  a  ship  a  faster  sailer,  a  more 
weatherly  or  safer  ship,  than  any 
other   curves  which   might  have 
been  adopted  in  the  construction 
of  the  ship's  body 
Architholua,  a  round  chamber,  the 

sudatorium  of  a  Roman  bath 
Architrave,  the  lower  of  the  three 
principal  members  of  the  entabla- 
ture of  an  order,  being  the  chief 
beam  resting  immediately  on  the 
column 
Architrave   cornice,  an  entablature 
consisting  of  an  architrave  and  cor- 
nice only,  without  the  interposition 
of  a  frieze 
Architrave  doors,  those  which  have 
an  architrave  on  the  jambs  and 
over  the  door 
Architrave  windows,  of  timber,  are 
usually  an  ogee  raised  out  of  the 
solid  ^mber,  with  a  roll  over  it 
Archivott,  a  collection  of  members 
in  the  face  of  an  arch,  concentric 
vrith  the  intradoBjt  and  supported 
by  imposts 


ARC 


ARK. 


ARK 


ArehwoH  of  the  arch  of  a  hridge, — 
the  curve  line  formed  by  the  upper 
sides  of  the  arch-stones  in  the  face 
of  the  work ;  it  is  sometimes  un- 
derstood to  be  th&  whole  set  of 
ardi-stones  which  appear  in  the 
face  of  the  work 
JrcMvoUunif  a  cesspool  or  common 

sewer 
Archway  f  an  aperture  in  a  building 

coyeied  with  a  yault 
Arcuia,  a  small  coffer  or  box 
Arcut,  an  area  in  the  form  of  an  an- 
cient basilica : 
^rcitf,  an  arch.  A  true  arch  is  formed 
of  a  series  of  wedge-like  stones  or 
of  bricks,  supporting  each  other, 
and  all  bound  together  by  their 
mutual  pressure 

ArcuS'twaiUf  in  mediaeval  architec- 
ture, the  lattice  separating  the  choir 
from  the  nave  in  a  basilica 

Arderittf  a  slate  used  in  Italy  for  co- 
vering roofs 

Ar^Of  in  geometry,  the  superficial 
content  of  any  figure 

AreaSf  in  computing  the  superficial 
content  of  land,  are  generally  ex- 
pressed in  statute  acres,  roods,  and 
perches.  The  acre  is  equal  to  10 
square  chains  of  66  j^feet,  or  22 
yards  in  length 

Arerutf  the  area  or  floor  of  an  amphi. 
theatre 

Arenariunif  an  amphitheatre,  ceme- 
tery, crypt,  or  sepulchre 

Areometer,  an  instrument  for  mea- 
suring the  density  or  gravity  of 
fluids 

Areopagus,  the  court  in  which  the 
areopagites,  or  supreme  judges  of 
Athens,  assembled 

Areostylos,  intercolumniations,  when 
their  distance  from  each  other  is 
four  diameters 

Arerde,  reared,  built,  or  raised  up 

Argand  lamp,  a  lamp  with  a  circular 
wick,  through  which  a  current  of 
air  passes 

Argent,  in  heraldry,  in  the  blazoning 
of  arms,  signifies  also  white  or  silver 

ArgyrocopHon,  the  mint  at  Athens 

Ark,  a  belter,  a  place  of  protec- 
tion from  fioods:   in  the  time  of 


28 


Moses  a  coffer  or  sort  of  bark,  | 
in  shape  and  appearance  like  a 
chest  or  trunk;  also  described  by 
Moses  as  a  little  vncker  basket  in 
which  he  was  exposed  on  the  Nile. 
The  ancients  inform  us  that  the 
Egyptians  used  on  the  Nile  barks 
made  of  bulrushes.  Noah's  Ark 
was,  in  all  probability,  in  form  like 
these  Egyptian  boats,  but  much 
larger.  If  we  reckon  the  Hebrew 
cubit  at  21  inches,  the  aik  of  Noah 
was  512  feet  long,  87  wide,  and 
52  high ;  and  the  internal  capacity 
of  it  was  357,600  cubical  cubits. 
K  we  suppose  the  cubit  to  be  only 
18  inches,  its  length  was  450  feet, 
its  vndth  75,  and  its  height  45. 
Its  figure  was  an  oblong  square; 
the  covering  had  a  declivity  to 
carry  off  water.  Its  length  ex- 
ceeded that  of  most  churches  in 
Europe.  The  wood  used  for  the  ark 
was  called  gopher-wood,  square 
pieces  of  wood,  cedar  or  box,  or 
woods  that  do  not  easily  perish; 
some  supposed  it  to  have  been  con- 
structed of  Cyprus  wood 

Ark :  **  And  this  is  the  fashion  which 
thou  shalt  make  it  of;  the  length 
of  the  ark  shaU  be  three  hundred 
cubits,  the  breadth  of  it  fifty  cubits, 
and  the  height  of  it  thirty  cubits." 
— Oen.  vi.  15. 

Ark  {Noah'e),  supposed  by  some 
authors  to  be  a  mere  variation 
from  the  customary  construction  of 
houses  for  residence,  and  to  change 
its  character  from  that  of  a  house 
for  standing,  to  that  of  a  house  for 
fioating.  Niebuhr  compares  it  with 
ordinary  houses  of  the  east,  that 
the  sides  are  constructed  of  upright 
supports  of  timber,  which  are  plas- 
tered over  with  clay.  The  appli- 
cation of  canes,  split  and  laid  across 
these  quarterings,  is  very  like  the 
usage  of  laths,  which  are  common 
every  where.  The  same  may  be 
said  of  the  coating  of  bitumen:  the 
substance  was  employed  on  account 
of  its  property  of  resisting  water ; 
the  mode  of  its  application  might 
be  similar  to  our  plastering. 


ARM 


ASPHALTUM. 


AS 


Armarhtm,  a  niche  or  cupboard  near 
the  side  of  an  altar 

Armiger,  in  heraldry,  an  armoor- 
beu'er,  an  esquire 

ArmSla,  an  ornament  worn  by  Greek 
men  and  women  as  a  bracelet  or  an 
wmlet 

Armowr,  a  defemdye  clothing  of  metal 

Amumry,  a  storehouse  or  room  in 
which  armour  is  preserved 

Amotta  (colour),  the  name  of  a  vege- 
table substance  from  the  'West 
Indies,  of  an  orange-red  colour, 
soluble  in  water  and  spirit  of  wine, 
but  very  fugitive  and  changeable, 
and  not  adapted  for  painting.  It  is 
principally  used  by  the  dyer,  and 
in  colouring  cheese.  It  is  also  an 
ingredient  in  lacquering 

Artmade,  embattled,  a  junction  of 
several  lines  forming  indentations 

Arritf  in  joinery  and  ipasonry,  the 
line  of  concourse,  edge,  or  meeting 
of  two  surfaces 

ArrufiOet,  a  slight  piece  of  timber 
of  a  triangular  section,  used  in 
raising  the  slates  against  chimney 
shafts,  &c. 

Jrrit  gutter  J  a  wooden  gutter  of  the 
y  form,  fixed  to  the  eaves  of  a 
building 

Jtrit-wiset  in  bricklaying,  tiles  laid 
diagonally 

Arronddlef  in  heraldry,  the  carved 
cross,  the  arms  which  terminate  in 
the  escutcheon 

Anehkn,  a  Russian  measure  of  length, 
equal  to  2i  feet  English 

Anenal,  a  building  for  naval  or  mili- 
tary stores 

Anemct  &  white  metal  of  a  crystal- 
line  appearance,  and  very  brittle. 
It  sublimes  out  of  the  air  unchanged 
at  360^,  but  in  air  it  is  oxidated, 
and  becomes  arsenious  acid;  it  is 
occasionally  found  alone,  but  is  ge- 
nerally combined  with  nickel,  co- 
balt, and  other  metals 

Artetian  weUSf  so  called  from  a  mode 
practised  in  Artois  in  boring  for 

water 
ArttfieeTf  one  who  possesses  a  supe- 
rior knowledge  as  an  artist  or  ma- 
nufacturer 


29 


Aaarotumf  a  kind  of  chequered  pav< 
ment  used  by  the  Romans 

Ath,  a  superiorwood of  British  growtl 
of  a  brownish  white,  with  a  shad 
of  green ;  it  is  tough  and  ebutic,  an 
superior  to  any  other  wood  expose 
to  sudden  shocks  and  strains;  use 
for  frames  of  machines,  wheel  car 
riages,  inside  work  of  fnumiture,  &c 

Ashlar y  a  term  applied  to  common  o 
free  stones  as  they  oome  out  of  tb 
quarry.  By  ashlar  is  also  mean 
the  facing  of  squared  stones  on  thi 
front  of  a  buOduig :  if  the  work  Im 
so  smoothed  as  to  take  out  thi 
marks  of  the  tools  by  which  th< 
stones  were  first  cut,  it  is  caUec 
plane  ashlar ;  if  figured,  tooled  ash- 
lar, or  random  tooled,  or  chiselled; 
or  boosted,  or  pointed:  if  the  stonet 
project  from  the  joints,  it  u  said  tc 
be  rusticated 

Ashlar,  or  Achehr,  hewn  stone,  used 
for  (lie  facings  of  walls 

Ashlerinff,  in  carpentry,  the  fixing  ol 

•  short  upright  quarterings  between 
the  rafters  and  the  floor 

Ash'pan,  in  locomotive  engines,  an 
iron  box,  open  to  the  front  only, 
attached  to  the  fire-box  to  receive 
the  ashes  from  the  fire 

Asphalt,  native  bitumen  used  with 
pitch  as  a  substitute  for  pavement 

AsphaUum,  a  bituminous  substance, 
used  for  pavements  and  as  a  build- 
ing material 

AsphaUum,  called  also  Bitumen, 
Mineral  Pitch,  &c.;  it  is  a  resinous 
substance  rendered  brown  by  the 
action  of  the  fire,  natural  or  artifi- 
cial. The  substances  employed  in 
painting  under  this  name  are  the 
residua  of  the  distillation  of  various 
resinous  and  bituminous  matters 
in  preparing  their  essential  oils, 
and  are  all  black  and  glossy  like 
common  pitch,  which  d^ers  from 
them  only  in  having  been  less 
acted  upon  by  fire,  and  in  their 
being  softer.  Asphaltum  is  prin- 
dpaUy  used  in  oil-painting;  for 
which  purpose  it  is  first  dissolved 
in  oil  of  turpentine,  by  which  it  is 
fitted  for  glazing  and  shading.   Its 


ASS 


ASSURANCE. 


ASS 


fine  brown  colour  and  perfect 
transparency  are  lures  to  its  free 
use  with  many  artists  notwith- 
standing the  certain  destruction 
which  awaits  the  work  on  which 
it  is  much  employed*  owing  to  its 
disposition  to  contract  and  crack 
from  changes  of  temperature  and 
the  atmosphere 

jitsayt  to  examine  and  proye  metals 

jissay  bakmett  a  yery  accurate  ba- 
lance, used  in  determining  the  ex- 
act weights  of  yery  small  bodies 

Assayhifft  ascertaining  the  qualities 
of  g^ld  and  silyer  with  respect  to 
their  purity 

Asgemblaget  in  carpentry  and  joinery, 
framing,  doyetailing,  &c. 

Assemblage  qf  the  Orders  in  archi- 
tecture,  the  placing  of  columns  upon 
one  another  in  the  several  ranges 

Asserts t  small  rafters  immediately 
beneath  the  tiles  of  a  roof 

Assurance^  or  Insurance^  a  contract  to 
make  good  a  loss 

Assurance  CompanieSf  or  SoctetteSfdit- 
ford  protection  to  persons  from  the 
chances  or  hazards  to  which  their 
property  or  interests  may  be  exposed. 
Assurance  on  human  life  is  a 
contract  by  which  a  certain  amount 
or  capital  is  secured  at  the  expira- 
tion of  a  stipulated  period,  either 
by  the  payment  of  a  specified  sum 
at  the  time  of  effecimg  the  assure 
ancej  or  by  the  annual  payment  of 
a  smaller  amount,  according  to  the 
age  of  a  person  whose  life  is  assured. 
A  person,  with  the  yiew  of  se- 
curing a  certain  sum  of  money  to 
his  family  after  his  death,  desires 
to  effect  an  assurance,  either  for  a 
determinate  period,  as  one,  three, 
fiye,  seven,  ten,  or  more  years,  or 
for  the  whole  term  of  his  life.  In 
the  first  case,  if  the  person  whose 
life  is  assured,  die  brfore  the  expi- 
ration of  the  term  specified  in  the 
policy,  his  inheritors  receive  the 
amount  for  which  the  assurance  has 
been  effected ;  but,  if  the  assured 
liye  beyond  that  period,  they  receive 
nothing,  and  the  assurer  reaps  the 
advantage  of  the  contingency.    In 

30 


the  latter  case, — ^that  is,  by  assur- 
ance for  the  whole  term  of  life, — 
the  inheritors  are  entitled  to  re- 
ceive the  amount  named  in  the 
policy,  upon  proof  of  the  death  of 
the  person  whose  life  has  been  as- 
sured. To  prevent  the  forfeiture 
of  the  policy,  it  is  in  all  cases  es- 
sentially important  that  the  con- 
ditions upon  which  it  has  been 
granted  be  strictly  complied  vrith. 

The  calculation  as  to  the  amount 
of  premium  should  be  made  ac- 
cording to  mathematical  expecta- 
tion,— ^that  is,  equitably  as  to  both 
parties,  allowing  a  fair  rate  of  pro- 
fit to  the  party  granting  the  assur- 
ance. If  the  terms  for  assuring 
£100  be  required,  for  one  year, 
the  probability  must  depend  on  the 
age  of  the  person  whose  life  is  pro- 
posed to  be  assured ;  and  in  equity 
the  sum  to  be  paid  should  be  equal 
to  the  yalue  of  the  expectation, 
multiplied  by  the  probability  of  its 
being  obtained.  Should  the  age  of 
the  person  be  40  years,  the  probabi- 
lity of  death  in  the  course  of  the 
year  vrill  be,  according  to  the  ta- 
bles of  mortality  generally  adopted, 
-gH^ ;  and  this  fraction,  multiplied 
by  100,  gives  the  price  of  the  as- 
surance, namely,  1*74  nearly.  The 
result,  according  to  the  tables  of 
mortality  used  in  France,  is  1*89. 
This  is  the  rate  charged  by  the 
*  General  Assurance  Company'  es- 
tabUshed  at  Brussels ;  but  the  *  Bel- 
gic  and  Strangers'  Union  Society' 
charges  at  the  rate  of  1*87.  Both 
societies  adopt  Dubillard's  table  of 
of  mortality,  which  is  deposited  in 
the  Bureau  of  Longitude  in  Paris. 

The  profit  to  the  assurer  thus 
appears  to  be  reduced  to  the  in- 
terest on  the  sum  paid  by  the  as- 
sured; but  persons  in  health  being 
alone  accepted,  the  chance  of  pro- 
fit thereby  becomes  considerable. 
For  a  longer  term  than  one  year, 
the  calculations  are  made  on  an 
estimate  of  the  probable  amount  of 
interest  derivable  from  the  pre- 
mium paid  by  the  assurer. 


f 


AST 


ATMOSPHERIC  RAILWAY. 


ATM 


Astely  in  miniog,  a  board  or  plank, 
an  arch  or  ceiling  of  boards,  oTer 
the  men's  heads  in  a  mine,  to  pro- 
tect them 

Aftragal,  a  small  moulding,  whose 
contour  is  circular,  at  the  neck  of 
the  shafts  of  columns,  next  the  apo- 
physes :  it  also  occurs  in  the  base 
of  Ionic  columns,  and  below  the 
fasciae  of  the  Corinthian  epistylium 

Aitronomy,  a  mixed  mathematical 
science,  which  treats  of  the  hea- 
venly bodies,  their  motions,  periods, 
eclipses,  magnitudes,  &c.,&nd  of  the 
causes  on  which  they  depend :  the 
knowledge  of  astronomy  is  essential 
in  navigation  and  in  measuring  the 
earth's  surface;  the  diameter  of 
this,  the  third  planet  in  the  system, 
is  7924  miles  and  7  furlongs 

Astylar,  a  term  which  expresses  the 
absence  of  columns  or  pilasters, 
where  they  might  otherwise  be 
supposed  to  occur 

Attplktif  in  mining,  a  small  ward  or 
stoppage  in  an  adit  or  mine,  to 
prevent  the  free  and  full  passage 
of  water,  by  damming  up 

Agyhmif  in  the  Greek  states,  the  tem- 
ples, altars,  sacred  groves,  and 
statues  of  the  gods ;  a  place  pro- 
"vided  for  the  protection  of  debtors 
and  criminals  who  fled  for  refuge 

Ataeamitef  piismatoidal  green  mala- 
chite, a  native  muriate  of  copper 

MhanoTf  an  ancient  term  for  a  metal 
furnaces 

MkefuBttm,  a  school  founded  by  the 
Emperor  Hadrian  at  Rome  for  the 
promotion  of  literary  and  scientific 
studies 

Athwart-hawae,  the  situation  of  a  ship 
when  driven  by  the  wind  or  tide 
across  the  fore-part  of  another 

Mlanteg,  in  architecture,  male  figures, 
used  similarly  to  the  female  Carya- 
tideSf  in  place  of  columns 

^trnogpheret  the  invisible  elastic  fluid 
which  surrounds  the  earth  to  an 
unknown  exact  height,  and  par. 
takes  of  all  its  motions ;  the  con- 
stituent parts  are — air,  water,  car- 
bonic acid  gas,  and  unknown  bodies. 
Theatmosphere  is  measured  by  a  co- 

^^31  """^  " 


lumn  of  mercury  of  29*922  inches, 
which  has  been  adopted  in  France 
as  the  mean  height  of  the  barome- 
ter at  the  surface  of  the  sea 
Atmospheric  currents,  in  high  lati- 
tudes, when  undisturbed,  are  west- 
erly, particularly  in  the  winter  sea- 
son.    If  storms  and  gales  revolve 
by  a  fixed  law,  and  we  are  able,  by 
studying  these  disturbing  causes  of 
the  usual  atmospheric  currents,  to 
distinguish  revolving  gales,  it  is 
likely  that  voyages  may  be  short- 
ened.   The  indications  of  a  revolv- 
ing gale  are,  a  descending  barome- 
ter, and  a  regularly  veering  wind 
Atmospheric   engine,   an   engine   in 
which  the  steam  is  admitted  only 
to  the  under  side  of  the  piston 
for  the  np-stroke ;  it  is  then  con- 
densed, and  the  top  of  the  cylinder 
being  open,  the    down-stroke  is 
caused  by  the  pressure  of  the  at- 
mosphere.   Marine  engines  on  this 
principle  have  three  cylinders  con- 
nected to  one  crank-shaft,  to  obtain 
uniformity  of  motion 
AtmosphericraUway,  The  conclusions 
drawn  by  Mr.  R.  Stephenson  are 
as  follows:  1st,  That  the  atmo- 
spheric system  is  not  an  economical 
mode  of  transmitting  power,  and 
inferior  in  this  respect  both  to  loco- 
motive engines  and  stationary  en- 
gines with  ropes.  2ndly,  That  it  is 
not  calculated  practically  to  ac- 
quire and  maintain  higher  veloci- 
ties than  are  comprised  in  the  pre- 
sent working  of  locomotive  engines. 
3rdly,  That  it  would  not  in  the  ma- 
jority of  instances  produce  economy 
in  the  original  construction  of  rail- 
ways, and  in  many  would  most  ma- 
teriaUy  augment  their  cost.    4thly, 
That  on  some  short  railways,  where 
the  trafilc  is  large,  admitting  of 
trains  of  moderate  weight,  but  re- 
quiring high  velocities  and  frequent 
departures,  and  where  the  face  of 
the  country  is  such  as  to  preclude 
the  use  of  gradients  suitable  for 
locomotive  engines,  the  atmospheric 
system  would  prove  the  most  eli- 
gible.    5thly,  That  on  short  lines 


ATM 


AUDITORIUM. 


AUD 


of  railway,  say  four  or  five  miles  in 
length,  in  thevicinity  of  large  towns, 
where  frequent  and  rapid  communi- 
cation is  required  between  the  ter- 
mini alone,  the  atmospheric  system 
might  be  advantageously  applied. 
Gtfaly,  That  on  short  lines,  such  as 
the  Blackwall  Railway,  where  the 
traffic  is  chiefly  derived  from  inter- 
mediate points,  requiring  frequent 
stoppages  between  the  termini,  the 
atmospheric  system  is  inapplicable, 
being  much  inferior  to  the  plan  of 
disconnecting  the  carriages  from  a 
rope,  for  the  accommodation  of  the 
intermediate  traffic.  7thly,Thaton 
long  lines  of  railway,  the  requisites 
of  a  large  traffic  cannot  be  attained 
by  so  inflexible  a  system  as  the 
atmospheric,  in  which  the  efficient 
operation  of  the  whole  depends  so 
completely  upon  the  perfect  per- 
formance of  each  individual  section 
of  the  machinery. 
Atmospheric  vapour.  Deluc  proves 
the  amount  of  force  and  vapour  in  a 
vacuum  of  any  given  dimensions 
is  equal  to  its  force  and  quantity 
in  an  equal  volume  of  air  at  the 
same  temperature,  or  that  the  tem- 
perature of  the  air  wUl  determine 
the  force  and  quantity  of  vapour 
held  in  it.  M.  Le  Roi,  however, 
first  observed  the  temperature  at 
which  dew  commences  to  be  de- 
posited as  a  rule  of  ascertaining 
the  moisture  of  the  atmosphere. 
Dr.  Dalton  investigated  the  force 
of  vapour  of  every  temperature, 
from  Zero  to  the  boiling  point  of 
water,  Fahrenheit,  and  expressed 
this  force  by  the  weight  of  the 
mercurial  column  it  coidd  support 
in  the  tube  of  the  barometer. 
Dalton  and  Le  Roi  find  the  clear 
point  by  pouring  cold  water  into  a 
glass,  and  markmg  the  temperature 
at  which  it  just  ceases  to  deposit 
dew  on  the  sides  of  the  glass  in  the 
open  air.  The  temperature  here 
observed  is  the  point  at  which  dew 
would  begin  to  be  formed.  From 
this  Dalton  infers  not  only  the 
force  exerted  by  the  vapour,  but 

^"32 


also  its  amount  in  a  perpendicular 
column  of  the  whole  atmosphere, 
and  likewise  the  force  of  evi^ra- 
tion  at  the  time  of  observation 

AtramerUum,  a  dye  made  of  soot 
mixed  vnth  burnt  resin  or  pitch, 
used  by  the  ancients,  particularly 
by  painters ;  and  also  as  a  varnish 

Atrium,  a  term  applied  by  the  Romans 
to  a  particular  part  of  a  private 
house ;  the  court  or  hall  of  a  Greek 
or  Roman  house  entered  imme- 
diately from  the  fauces  of  the  ves- 
tibilium 

Attalf  Attkf  AdaU,  Addle,  in  mining, 
corrupt,  impure  off-casts  in  the 
working  of  mines 

Attic  bate,  the  base  of  a  column  of 
upper  and  lower  torus,  a  scotia, 
and  fillets  between  them 

Attic  Order,  a  low  order  of  architec- 
ture, used  over  a  principal  order, 
never  with  columns,  but  with  ants 
or  small  pilasters 

Attics  should  not  be  less  than  one- 
quarter  nor  more  than  one-third 
of  the  order  they  surmount :  they 
are  frequently  decorated  with  small 
short  pilasters,  whose  breadth 
ought  to  be  equal  to  the  upper 
diiuneter  of  the  column  underneath 
them,  and  their  projection  usually 
not  more  than  one-quart-er  of  their 
breadth 

Attic  story,  the  upper  story  of  a  house 
when  the  ceiling  is  square  with  the 
sides,  by  which  it  is  distinguished 
from  a  common  garret 

Atticwrgus,  a  term  applied  by  Vitru- 
vius  to  the  base  of  a  column,  which 
he  describes  as  divided  by  a  scotia 
or  trochilus,  with  a  fillet  above 
and  below,  and  beneath  all  a  plinth 

Attle,  in  mining,  rubbish,  deads,  re- 
fuse, or  stony  matter 

Attributes,  in  architecture,  symbols 
given  to  figures,  or  disposed  as 
ornaments  on  a  building,  to  indicate 
a  distinguished  character 

Attrition,  the  rubbing  of  bodies  one 
against  another,  so  as  to  destroy 
their  surfaces 

Auditorium,  an  apartment  in  monas- 
teries for  the  reception  of  strangers ; 


AUG 


AXIS. 


AXL 


also  a  place  where  the  Roman  ora- 
tors and  poets  recited  their  compo- 
sitions 

Auger,  a  tool  for  horing  large  holes ; 
it  consists  of  a  wooden  handle,  ter- 
minated at  the  bottom  with  steel 

Auta^aii  area  or  open  pkce;  in  ancient 
Roman  architecture,  a  court  or  hall 

Auleobtm,  a  small  church  or  chapel 

AureolOf  a  crown  of  glory,  given  by 
statuaries,  &c.  to  saints,  &c.  to  de- 
note the  victory  they  have  obtained 

Aurificina,  a  place  for  melting  and  re- 
fining gold,  &c. 

Aurttm,  anciently,  gold 

Autfjmattm,  an  apparently  self-acting 
machine,  constructed  of  weights, 
levers,  piiUeys,  and8prings,by  means 
of  which  it  continues  in  motion  for 
a  definite  period 

Autometer,  an  instrument  to  mea- 
sure the  quantity  of  moisture 

Avenue,  a  passage  from  one  part  of  a 
builduig  to  another 

Avuny,  an  apartment  or  building  for 
the  keeping  of  birds 

AfBotta,  a  place  vaulted  or  arched  over 

A-weather,  the  situation  of  the  helm 
of  a  ship  when  it  is  put  in  the  di- 
rection from  which  the  wind  blows 

Awning,ti  covering  of  canvass  over  the 
deck  of  a  vessel,  or  over  a  boat,  as 
shelter  from  the  sun  or  rain 

Axal  tectum,  a  section  through  the 
axis  of  a  body 

Axet,  the  timbers  of  a  roof  which 
form  two  sides  of  a  triangle,  the 
tignum  being  the  base ;  more  gene- 
rally termed  Principals 

Axiom,  a  self-evident  truth 

Axit,  in  architecture,  an  Imaginary 
line  through  the  centre  of  a  column, 
&c.,  or  its  geometrical  representa- 
tion :  where  different  members  are 
placed  over  each  other,  so  that  the 
same  vertical  line,  on  the  elevation, 
divides  them  equally,  they  are  said 
to  be  on  the  same  axis,  although 
they  may  be  on  different  planes : 
thus,  triglyphs  and  modillions  are 
80  arranged,  that  one  coincides  with 
the  axis  or  line  of  axis  of  each  co- 
lumn :  in  like  manner,  the  windows 
or  other  openings  in  the  several 


stories  of  a  facade  must  all  be  in  the 
same  respective  axis,  whether  they 
are  all  of  the  same  breadth  or  not 

Axis,  in  geometry,  the  straight  line  in 
a  plane  figure,  about  which  it  re- 
volves to  produce  or  generate  a  solid 

Axis,  in  mechanics:  the  axis  of  a 
balance  is  the  line  upon  which  it 
moves  or  turns 

Axis,  in  turning,  an  imaginary  line 
passing  longitudinally  through  the 
middle  of  the  body  to  be  turned, 
from  one  point  to  the  other  of  the 
two  cones,  by  which  the  work  is 
suspended,  or  between  the  back 
centre  and  the  centre  of  the  collar 
of  the  puppet  which  supports  the 
end  of  the  mandril  at  the  chuck 

Axis  qf  a  circle  or  sphere,  any  line 
drawn  through  the  centre,  and  ter- 
minated at  the  circumference  on 
both  sides 

Axis  of  a  cone,  the  line  from  the 
vertex  to  the  centre  of  the  base 

Axis  of  a  cyUnder,  the  line  from  the 
centre  of  the  one  end  to  that  of  the 
other 

Axis  in  peritrochio,  a  wheel  and  axle, 
one  of  the  five  mechanical  powers, 
or  simple  machines;  contrived 
chiefly  for  the  raising  of  weights  to 
a  considerable  height,  as  water 
from  a  well,  &c. 

Axis  qf  rotation,  of  any  solid,  the  line 
about  which  the  body  really  re- 
volves when  it  is  put  in  motion 

Axle  bearing,  in  locomotive  engines, 
the  gun-metal,  or  other  metal  bear- 
ing, under  which  the  axle  journal 
revolves :  it  is  nicely  fitted  to  the 
journal,  and  lubricated  by  a  syphon, 
to  reduce,  as  far  as  practicable,  the 
friction  on  the  journal 

Axle,  in  locomotive  engines.  Journal 
or  neck,  the  part  of  the  axle  turned 
and  polished  for  revolving  in  the 
axle-box  bearing 

Axle,  leading,  in  locomotive  engines, 
the  front  axle  of  the  engine:  eight- 
wheeled  engines  have  two  axles  in 
front  of  the  driving  wheel  axle,  and 
they  are  often  called  leading  axles 

Axle,  trading,  the  last  axle  of  the  en- 
gine, usually  placed  under  the  foot- 


33 


b5 


AXL 


BABYLONIAN  ARCHITECTURE. 


AZU 


plate:  in  Stephenson's  and  Cramp- 
ton's  patent  engines,  the  driving 
wheel  axle  is  the  last  axle 

Axles,  in  locomotive  engines,  the  iron 
shafts  supporting  the  engine,  and 
on  which  the  wheels  are  fixed 

Axlet:  driving  wheel;  in  locomotive 
engines,  with  inside  cylinders,  this 
is  a  cranked  axle;  with  outside 
cylinders,  it  is  a  straight  axle :  it 
is  called  the  driving  axle  because 
the  connecting-rods  and  eccentric- 
rods  connect  this  axle  to  the  pis- 
tons, slide-valves,  and  pumps,  and 
by  converting  the  rectilinear  mo- 
tion of  the  piston  into  a  rotatory 
one,  it  propels  or  drives  the  engine 
in  the  direction  required 

Axle-box,  in  locomotive  engines,  the 
box  (usually  cast  iron)  fitted  up  with 
a  mefcal  bearing  in  it,  which  rests 
upon  the  polished  part  of  the  axle 

Axle-box  coo^,  in  locomotive  engines, 
the  plate  of  iron  (usually  lined  with 
leather)  fitted  to  the  top  of  the 
axle-box  to  keep  the  oil  clean,  and 
also  from  shaking  out  by  the  motion 
of  the  engine 

Axle-box  syphon,  in  locomotive  en- 
gines, the  small  tubes  fitted  into  the 


BAB 


Babel,  tower  of,  built  by  the  posterity 
of  Noah,  after  the  Flood ;  remark- 
able for  its  great  height,  and  for 
the  disappointment  of  the  builders 
by  the  confusion  of  their  language. 
It  was  erected  in  the  plain  of  Shi- 
nar,  upon  the  banks  of  the  great 
river  Euphrates,  and  near  the  place 
where  the  famous  city  of  Babylon 
subsequently  stood.  <'  Let  us  build 
us  a  city  and  a  tower  whose  top 
may  reach  unto  heaven." — Gen,  xi. 
4.  ***"ThenameofitispaUed 
Babel,  because  the  Lord  did  there 
confound  the  language  of  all  the 
earth,  and  from  thence  did  the 
Lord  scatter  them  abroad  upon  the 
face  of  all  the  earth/*— 7J.  xi.  9 

Babylonian  architecture  takes  its  ap- 
pellation from  the  magnificence  and 
extent  of  the  public  buildings  of 


top  of  the  axle-box  for  feeding  oil  on 
to  the  axle  journal  as  it  revolves : 
the  oil  is  fed  by  a  piece  of  cotton 
or  worsted,  having  one  end  intro- 
duced into  these  pipes,  and  the  other 
end  lying  down  amongst  the  oil  in 
the  axle-box 

Axle-ffuarde,  or  hom-platee,  in  loco- 
motive engines,  the  parts  of  the 
frame  in  which  the  axle-box  slides 
up  and  down,  as  acted  upon  by 
the  springs 

Axle-ffuard  stays,  in  locomotive  en- 
gines, the  iron  rods  bolted  to  the 
frame  and  to  all  the  ends  of  the 
axle-guards,  to  strengthen  them 

Azimuth  conqioMS,  an  instrument  used 
at  sea  for  finding  the  son's  magnetic 
azimuth 

Azimuth  dial,  a  dial  of  which  the  style 
or  gnomon  is  perpendicular  to  the 
plane  of  the  horizon 

Azote,  in  chemistry,  an  important 
constituent  of  atmospheric  air,  &c.; 
also  a  gas  called  nitrogen,  which, 
when  breathed  alone,  destroya  life 

Azure,  in  heraldry,  the  blue  colour, 
in  the  shields  of  all  persons  under 
the  rank  of  baron :  in  painting,  a 
light  or  sky-coloured  blae 


BAB 


Babylon.  This  city  was  founded 
by  Nimrod  about  1665  years  before 
Christ:  its  walls  were  50  cubits 
thick  and  200  in  height,  built  of 
bricks  made  from  the  earth  dug 
out  of  the  ditch  that  surrounded 
the  city.  In  the  walls  were  100 
gates  made  of  brass ;  the  jambs  and 
lintels  were  made  of  the  same  metal 
BcAyUman  engine.  The  engine  that 
raised  water  from  the  Euphrates  to 
supply  the  hanging  gardens  of  Ba- 
bylon was  constructed  and  used  in 
this  the  most  ancient  and  splendid 
city  of  the  early  age,  founded  by  the 
builders  of  Babel,  and  enlarged  by 
Nimrod;  extended  and  beautified 
by  Semiramis.  This  engine  greatly 
exceeded  in  the  perpendicular  the 
the  height  to  which  the  water  was 
elevated  by  it.    Extensive  terraces 


/ 


BAG 


BALANCE  IN  A  PICTURE. 


BAL 


were  formed  one  above  another  to 
the  top  of  the  city  walls ;  and  to 
supply  them  with  the  necessary 
moisture,  the  engine  was  erected, 
of  which  no  account  is  known  at 
the  present  time 

BaCf  in  nayigation,  a  praam  or  ferry- 
boat 

Bae,  in  brewing,  a  cooler 

Baeealaureug,  an  ecclesiastical  appari- 
tor or  Terger,  who  carries  a  staff 
of  office 

BaeeOf  a  light-house,  watch-tower,  or 
beacon 

BacckarU,  a  ploughman's  spikenard 

Back,  the  back  of  a  lode  is  the  part 
of  it  nearest  the  surface ;  the  back 
of  a  level  is  that  part  of  the  lode 
extending  above  it  to  within  a  short 
distance  of  the  level  above 

Back-doard,  in  turning,  that  part  of 
the  lathe  which  is  sustained  by  the 
foor  legs,  and  which  sustains  the 
pillars  tiiat  support  the  puppet-bar ; 
the  back-board  is  only  used  in  the 
best  constructed  lathes 

Baei  centre  tcrewj  the  screw  for  set- 
ting up  the  back  centre  of  a  lathe, 
to  the  work  to  be  turned,  after  the 
puppet-head  has  been  fixed 

Backed,  a  sea  phrase,  to  back  an  an- 
chor, to  carry  out  a  smaller  one  a- 
bead  of  the  one  by  which  the  vessel 
lides,  to  take  off  some  of  the  strain 

Bock-grfmnd,  in  painting,  is  the  space 
of  ground  behind  the  principal  ob- 
jects of  the  picture 

Back4ink9,  the  links  in  a  parallel  mo- 
tion which  connect  the  air-pump 
rod  to  the  beam 

^h  of  a  hipj  in  carpentry,  is  the 
apper  edge  of  a  rafter  between  two 
tides  of  a  hipped  roof,  formed  to  an 
angle,  so  as  to  range  with  the  raft- 
en  on  each  side  of  it 

Back  of  a  vrmdowt  the  board  or  wain- 
iGOtingbetween  the  sash-framesand 
theiloor,unitingwith  the  twoelbows 
in  the  same  plane  with  the  shutters : 
when  framed  it  is  commonly  with 
liQgle  panels,  with  mouldings  on 
the  framing  corresponding  with  the 
doors,  shutters,  &c.,  in  the  apart- 
ment in  which  it  ia  fixed 


Baek-painiinff,  the  art  of  painting 
mezzotinto   prints,    on   plate   or 
crowned  glass  with  oil  colours 
Backg,    in   carpentry,  the  principal 

rafters  of  a  roof 
Back-ttaff,  an  instrument  invented  by 
Capt.  Davis  for  a  sea  quadrant,  so 
named  because  the  back  of  the  ob- 
server is  turned  towards  the  sun 
when  using  it 
Baek^tayMf  long  ropes  from  the  top- 
mast h^uls  to  both  sides  of  the 
ship,  where  they  are  extended  to 
the  channels 

Back-etay  etool,  a  short  piece  of  plank 
fitted  for  the  security  of  the  dead 
eyes  and  chains  for  the  back-stays, 
though  sometimes  the  channels  are 
left  long  enough  at  the  after  end  for 
the  back -stays  to  be  fitted  thereto 

Bac-maker  a  cooper  who  makes 
liquor  bacs,  &c. 

Baculometryt  the  art  of  measuring 
either  accessible  or  inaccessible 
lines,  by  the  help  of  baculi,  staves, 
or  rods 

Badigeon,  in  statuary,  a  mixture  of 
plaster  and  freestone  sifted  and 
ground  together,  used  by  statuaries 
to  repair  defects  in  their  work 

Bagnette,  a  small  moulding,  like  the 
astragal :  when  enriched  with  foli- 
age, it  is  called  a  chaplet;  when 
plain,  a  head 

Bagnio,  a  bath 

Bagpipe.  To  bagpipe  the  mizen  is  to 
lay  it  aback  by  bringing  the  sheet 
to  the  weather-mizen  rigging 

Bailey f  an  area  of  ground,  a  court 
within  the  walls  of  a  fortress ;  in 
modem  acceptation,  frequently  used 
as  prison 

Bakehouse f  an  apartment  with  an  oven 

'^  to  bake  bread 

Baker' 8  central  rule  for  the  construc- 
tion of  equations;  is  a  method  of 
constructing  all  equations  not  ex- 
ceeding the  4th  degree 

Bal,  a  term  used  in  mining 

Balance,  or  equilibrium,  in  a  picture, 
is  when  the  forms  of  objects,  the 
lights,  shades,  colours,  and  expres- 
sions,  are  happily  adapted  to  each 
other,  and  no  one  figure  or  colour 


35 


BAL 


BALANCE  GATES. 


BAL 


overpowers  or  obscures  the  rest. 
When  a  bmlding  is  seen  in  one 
comer  of  a  picture,  it  is  frequently 
balanced  by  something  in  the  other; 
even  a  large  burd  will  have  the 
effect 

Balanee,  one  of  the  six  simple  powers 
in  mechanics,  chiefly  used  in  de- 
termining the  equality  or  diffier- 
ence  in  heavy  bodies,  and  conse- 
quently their  masses  or  quantities 
of  matter 

Balance fiamechamafaieYmooB;  the 
common  balance,  the  bent  lever 
balance,  the  Roman  balance,  and 
the  Swedish  or  Danish  balance, — 
a^jostmentof  differences  in  weights, 
&c 

Balance  (Hydrostatical),  an  instru- 
ment  for  determining  the  specific 
gravity  of  bodies 

Balance,  of  a  clock  or  watch,  is  that 
part  which,  by  its  motion,  regulates 
and  determines  the  beats 

Balance  gates,  in  hydraulic  engineer- 
ing, are  best  described  as  follows : 
Balance  gates  at  the  Compensation 
Reservoir  of  the  East  London  Wa- 
ter Works. — ^Thcse  gates  were  de- 
signed for  the  purpose  of  discharg- 
ing the  body  of  water  collected  in 
the  reservoir  during  the  rise  of  the 
tide,  in  order  to  supply  the  mills 
lower  down  the  river  Lea,  which 
might  otherwise  have  been  injured 
by  the  amount  withdrawn  from 
the  river  by  the  pumping-engines 
of  the  water  company.  They  dif- 
fer in  construction  from  common 
flood-gates,  being  made  to  work 
upon  a  vertical  shaft  or  spindle,  as 
a  centre,  and  having  an  equal  sur- 
face  of  gate  on  each  side  of  that 
centre,  so  that  whatever  pressure 
of  water  there  may  be  on  one  side 
of  the  gate  tending  to  forde  it  open, 
there  is  as  great  a  pressure  on  the 
opposite  lei^  to  keep  it  shut 

Balance  reef,  a  reef  in  a  spanker  or 
fore-aft  mainsail,  which  runs  from 
the  outer  head  eaving  diagonally  to 
the  tack;  it  is  the  closest  reef,  and 
makes  the  sail  triangular 

Balcony,  a  projection  in  the  front  of 

~36 


a  house  or  other  building,  supported 
by  consoles  or  columns,  sometimes 
applied  to  the  interiors  of  theatres, 
and  for  public  convenience  in  larger 
buildings 

Balcony,  the  projecting  gallery  in  the 
stem  of  large  ships 

Baldachin,  a  canopy  supported  by 
columns,  and  raised  over  altars, 
tombs,  &c 

BiUdachino,  in  architecture,  an  open 
building  supported  by  columns  and 
covered  with  a  canopy^  frequently 
placed  over  an  altar 

Bale.  To  bale  a  boat,  is  to  throw  water 
out  of  her 

BalisUcs,  used  by  some  for  projectiles 
in  the  art  of  throwing  heavy  bodies 

BaUitraria,  a  room  in  fortified  build- 
ings, wherein  the  crossbows  were 
deposited 

Ball,  is  any  spherical  body,  either 
natural  or  artificial 

BaUaet,  for  ships,  materials  for  which 
consist  of  gravel,  iron,  or  stone,  or 
any  heavy  substance,  to  stow  away 
in  the  hold,  to  bring  a  ship  to  a 
proper  water-line  when  unladen, 
and  counterbalance  the  effect  of  the 
wind  on  the  masts,  and  to  give  sta- 
bility 

BalUcoek,  a  hollow  globe  of  metal  at- 
tached to  the  end  of  a  lever,  which 
turns  the  stopcock  of  a  cistem-pipe 
by  floating  on  the  surface  of  the 
water,  thereby  regulatingthe  supply 

Ball  flower,  an  ornament  like  a  ball, 
placed  in  a  circular  flower,  the  pe- 
tals of  which  form  a  cap  round  it, 
and  belongs  to  the  decorated  style 
of  the  14th  century 

Bad  of  a  penduhim,  is  the  weight  at 
the  bottom  of  it,  and  is  sometimes 
called  the  bob 

Ball  and  socket,  an  instmmoit  made 
of  brass  with  a  perpetual  screw,  so 
as  to  move  horizontally,  vertically 
or  obliquely,  and  is  used  for  the 
managing  of  surveying  and  astro- 
nomical instruments 

BallUta,  in  practical  geometry,  the 
same  as  the  geometrical  cross, 
called  the  Jacob's  Staff 

Ballistic  Pendulum  is  an  instrument 


BAL 


BALUSTRADES. 


BAN 


for  meastuing  the  'velocity  of  a 
cannon  ball,  t.  0.  the  force  of  gun- 
powder. It  consists,  in  its  simples^ 
form,  of  a  beam,  which  can  swing 
on  a  fixed  axis  at  one  end,  while 
the  ball  strikes  the  other  end;  and 
the  angle  through  which  that  end 
moyes  being  known,  the  velocity 
of  the  cannon  ball  may  be  com- 
puted 

BaOoath  a  spherical  hollow  body, 
floating  in  the  air  by  means  of  its 
inflation  with  gas  specifically  lighter 
than  the  atmosphere 

Balloon,  a  globe  placed  on  the  top  of 
a  piUar  or  pediment^  as  an  acroter 
or  crowning 

BaUsy  in  electricity,  invented  by  Mr. 
Canton,  are  two  pieces  of  cork  or 
pith  of  elder-tree,  nicely  turned  in 
a  kthe  to  the  size  of  a  small  pea, 
and  suspended  by  delicate  threads 

Ball  valveSf  the  valves  in  the  force- 
pumps  of  a  locomotive  engine :  the 
balls  are  turned  and  ground  truly 
spherical,  so  as  to  fit  water-tight 
into  the  valve-seats  in  every  position 

Baheae,  in  Greek,  signifies  a  bath  or 
bathing  vessel 

BaUeum,  a  band  or  girdle,  according 
to  Vitmvius :  this  word  is  used  to 
denote  the  moulding  on  the  bolsters 
or  sides  <^  the  Ionic  capital 

Balteif  the  bands  in  the  flanks  of 
Ionic  pulvinatcd  capitals.  Balteum 
and  balteus  were  generally  used 
by  the  Romans  to  signify  the  belt 
hy  which  the  sword  or  quiver  was 
suspended 

Bahuter,  a  small  column  or  pillar, 
used  in  a  balustrade 

Bahutert,  placed  round  the  gallery 
in  the  stem,  and  likewise  m  the 
quarter  gallery  of  large  ships 

Bahutrade,  a  series  or  row  of  balus- 
tere,  joined  by  a  rail,  serving  for  a 
rest  to  the  arms,  or  as  a  fence  or 
indosure  to  balconies,  altars,  stair- 
cases,^ &c. 

B^tnuUSf  when  intended  for  use, 
IS  against  windows,  on  flights  of 
steps,  terraces,  and  the  like,  should 
not  be  more  than  three  feet  six 
inches,  nor  less  than  three  feet  in 


height.  When  used  for  ornament, 
as  on  the  summit  of  a  building, 
their  height  may  be  from  two- 
thirds  to  four-fifths  of  the  entabla- 
ture whereon  they  are  employed : 
and  this  proportion  is  to  be  taken 
exclusive  of  their  zoccolo  or  plinth, 
so  that  from  the  proper  point  of 
sight  the  whole  balustrade  may  be 
exposed  to  view.  There  are  vari- 
ous species  of  balusters ;  if  single- 
bellied,  the  best  way  is  to  divide 
tbe  total  height  of  the  space  al- 
lotted for  the  balustrade  into  thir- 
teen equal  parts, — the  height  of 
the  baluster  to  be  eight,  of  the  base 
three,  and  of  the  cornice  two  of 
those  parts;  or  divide  the  total 
height  into  fourteen  parts,  making 
the  baluster  eight,  the  base  four, 
and  the  cornice  two.  If  double- 
bellied,  the  height  should  be  di- 
vided into  fourteen  parts,  two  of 
which  are  to  be  given  to  the  cor- 
nice, three  to  the  base,  and  the  re- 
mainder to  the  baluster. 

The  distance  between  two  ba> 
lusters  should  not  be  more  than 
half  the  diameter  of  the  baluster  in 
its  thickest  part,  nor  less  than  one- 
third  of  it; — ^but  on  inclined  planes 
the  intervals  should  not  be  quite  so 
wide. — Ovnlt. 

Band,  in  architecture,  denotes  any 
flat  low  member,  or  moulding,  that 
is  broad  and  not  very  deep 

Banderole,  in  heraldry,  a  narrow  flag 
or  streamer  affixed  under  the  crook 
of  a  crosier,  and  folding  over  the 
staff 

Bandlet,  a  small  fillet,  or  flat  moulding 

Bandrol,  a  little  flag  or  streamer 
affixed  to  the  top  of  masts 

Bank,  a  long  piece  of  timber 

Bank,  To  double  bank  an  oar,  is  to 
have  it  pulled  by  two  men 

Banker,  in  bricklaying,  is  a  bench 
from  6  to  12  feet  in  length ;  is  used 
for  preparing  the  bricks  for  gauged 
work 

Banker,  a  cushion  or  covering  fo»  a 
seat 

Banneret,  in  heraldry,  a  knight  made 
in  the  field 


37 


BAN 


BAR  IRON. 


BAR 


Banquet  J  the  raised  footway  adjoining 
to  the  parapet  on  the  sides  of  a 
bridge 

Bagptateriumj  a  back  mill  or  fulling 
mill 

Baptistery f  a  place  or  edifice  where 
baptism  is  performed.  A  basin, 
pool,  or  place  for  bathing 

Bar^  a  hairier,  gatehouse :  in  law,  a 
place  where  counsellors  plead 

Bar,  a  bank  or  shoal  at  the  entrance 
of  a  harbour 

Bar  of  ground,  in  mining,  any  course 
of  vein  which  runs  across  a  lode,  or 
different  from  those  in  its  vicinity 

Barberry  wood  is  of  small  size,  re- 
sembling alder,  and  is  straight  and 
tenacious 

Barbican,  in  the  middle  ages,  the 
part  of  a  fortress  where  watch  and 
ward  was  kept 

Barcella,  a  vessel  containing  incense 

Barcon,  a  luggage  vessel  used  in  the 
Mediterranean 

Bardiglione,  a  blue  variety  of  anhy- 
drite, cut  and  polished  for  orna- 
mental purposes 

Bare  poles,  the  condition  of  a  ship 
when  she  has  no  sail  set 

Barge,  a  large  double-banked  boat 
used  by  the  commander  of  a  vessel 
in  the  navy 

Barge  board,  the  front  or  facing  of 
the  former,  to  conceal  the  barge 
couples,  laths,  tiles,  thatch,  &c. 

Barge  boards,  or,  more  properly, 
verge  boards,  pendants,  pinnacles, 
and  brackets,  being  the  chief  deco- 
rations of  houses  in  early  domestic 
architecture,  should  always  be 
noade  of  strong  oak,  and  left  to 
acquire  by  age  a  grey  hue;  and 
not  of  slight  deal,  painted,  as  is 
now  the  too  frequent  practice 

Barge  cmiples,  in  architecture,  a  beam 
mortised  into  another,  to  strengthen 
the  building 

Barge  course,  a  part  of  the  tiling  or 
thatching  of  a  roof,  projecting  over 
the  gable,  and  filled  up  with  boards, 
mortar,  &c. . 

Bar  iron,  long  prismatic  pieces  of 
iron,  being  rectangular  parallelopi- 
■ox^Am  TWATtoTwH  from  oiflT  ironi  so  as 


to  be  malleable  for  the  use  of  black- 
smiths for  the  method  of  joining 
bars 

Barium,  a  metal  that  exists  in  the 
sulphate  and  carbonatje  of  barytes; 
found  in  nature  in  great  abund- 
ance 

Barker^s  miU,  an  hydraulic  machine 
in  much  use 

Barkery,  a  tan-house;  also  a  sheepcote 

Barmkyn,  the  rampart  or  outer  forti- 
fication of  a  castle 

Bam,  a  covered  farm-building  for 
laying  up  grain,  hay,  straw,  &c. 

Bamack,  a  dieU  fish  often  found  on 
a  vessel's  bottom 

Barometer  and  Sympiesometer.    The 
barometer  is  a  measure   for  the 
weight  of  the  atmosphere,  or  its 
pressure  on  the  surface  of  the  globe. 
It  is  well  known,  that  it  is  owing 
to  the  atmospheric  pressure  that 
water  rises  in  a  common  pump,  after 
the  air  has  been  drawn  from  the 
barrel ;  but  that  the  height  to  which 
it  can  be  raised  by  tMs  means  is 
limited,  and  not  much  exceeds  30 
feet.    A  little  more  than  30  feet  of 
water,  therefore,  balances  the  at- 
mosphere.    Mercury  being  about 
twelve  times  heavier  than  water, 
about  30  inches  of  mercury  will 
also  counterpoise  the  atmosphere. 
The  principle  of  the  barometer  is 
simple.    If  a  tube,  about  3  feet 
long,  closed  at  one  end  and  open  at 
the  other,  be  filled  with  mercury, 
and,  with  the  open  end  stopped 
by  a  finger,  this  tube  be  rtveaned, 
and  placed  upright  in  a  cup  partly 
filled  with  the  same  liquid,  the 
mercury  in  the  tube,  in  ordinary 
states  of  the  weather,  will  descend  I 
to  30  inches,  measured  from  the  i 
sariauce  of  the  fluid  in  the  cup,  and 
not  much  lower.    The  mercury  is  I 
sustained  in  the  tube  by  the  pres-  j 
sure  of  the  atmosphere  on  the  sur- 1 
face  of  the  fluid  in  the  cupt    Such 
a  tube  and  cup,  so  filled,  would  in 
fact  be  a  barometer ;  and  if  a  move* 
able  index  were  added  to  it,  this 
simple  instrument  would  indicate 
the  changes  which  take  place  in  the 


BAR 


BAROMETER. 


BAR 


atmospheric  pressure.  The  sympie- 
someter  is  a  more  delicate  instru- 
ment, for  measuring  the  atmospheric 
pressure ;  but  it  is  also  a  more  com- 
plicated one  than  the  mercurial 
harometer,  and  it  would  be  best  un- 
derstood by  inspection.  The  upper 
part  of  the  tube  contains  hydrogen 
gas,  which  is  elastic ;  and  the  lower 
part,  including  the  weU,  contains 
oiL  By  this  compound  construc- 
tion, whilst  the  length  of  the  tube 
is  less  than  that  of  the  mercurial 
barometer,  the  index,  or  scale  for 
measuring  the  pressure,  is  increased. 
Hydrogen  gas  being  very  sensibly 
affected  by  all  changes  of  tempe- 
rature, the  index,  by  wbich  the  at- 
mospheric  pressure  is  read,  requires 

Seduction  of  the   English  Barometer  to 

Fahrenheit's  Scale- 


to  be  set  according  to  the  actual 
temperature,  before  the  atmospheric 
pressure  can  be  read  off. 

Since  mercury  expands  by  heat, 
a  correction  for  temperature  is  also 
required  for  the  mercurial  barome- 
ter, when  exact  calculations  are  to 
be  made;  and  for  this  reason  ba- 
rometers usually  have  athermometer 
attached  to  them,  in  order  that  the 
temperature  may  be  read  off,  and 
recorded  at  the  same  time  that  the 
barometer  is  registered. 

The  following  is  a  table  for  the 
correction  to  be  applied  to  the  ob- 
served height  of  the  mercury,  to 
reduce  it  to  the  freezing  point,  at 
32°  Fahrenheit,  or  zero  of  the  cen- 
tigrade  scale. 

the  Freezing  Point,  or  to  32°  on 
-Subtraetwe, 


Tempi 


Fah. 

o 

3S 
34 
S6 
38 
40 
43 
44 
46 
48 
50 


53 
54 
56 
58 
60 
63 
64 

68 
70 


73 

74 
76 
78 
80 
83 
84 
86 
88 
90 


Cent. 

Voo 

1-11 
2*22 
8*33 
4-44 

5*55 
6-66 

7'T7 

8*88 

10*00 


11*11 
12*22 
1S'S3 
14*44 
16*55 
16-66 

17-77 
18*88 
20*00 
21*11 


22*22 
23-33 
24*44 

25*55 
26*60 

^'77 

28*88 
30*00 
31*11 
32*22 


PA.KT  I. — For  Mercury  only. 


Hagbt  of  the  Barom.  in  Inches. 


28  In. 


O'OOOO 
0*0056 
0*0112 
0-0108 
0*0224 
0*O280 
0-0336 
0*0392 
0*0448 
0*0504 


39  In. 


O'OOOO 
0*0058 
0*0116 
0-0174 
00332 
0*0290 
0*0348 
0*0406 
00464 
0*0523 


0*0559 
0*061 5 

0-0671 
0*0727 
0*O783 
0-0838 
0*0804 
O-O050 
0-1 O06 
0*1061 


0*0579 

0*0637 
0-0695 
0*0753 

0*0811 
0*0868 
0*0936 
0*0984 
0*1041 
0*1099 


P,  P.  for 
Temp.  F.  •♦• 


0*1117 
0-1173 
0'1228 
0-1 283 
0-1330 
0-1304 
0*1450 
0*1505 
0*1561 
0-1617 


0*1156 
0*1314 
8*1371 
0*1329 
0*1387 
0*1444 
0*1603 
0*1559 
0'l6l6 
0-1674 


30  In. 


0*0000 
0*0060 
0*0120 
0-0180 
0-0240 
0*0300 
0*0360 
0*0430 
0*0480 
0*0540 


0*0599 
0*0659 

0*0719 
00779 
00839 
0*0898 
0*0958 
0*1018 
0*1077 
0*1137 


0*1196 
0*1356 
0*1315 
0*1375 
0*1434 
0*1494 
0*1553 
0'l6l3 
0*1673 
0*1731 


31  In. 


0-0000 
0*0063 
0*0134 
0*0186 
0*0348 
0*0310 
0*0373 
0*0434 
0*0496 
0*0558 


0*0619 
0*0681 
0*0743 
0-0805 
O-O867 
0*0928 
0-0990 
0-1051 
0*1113 
0-1175 


0*1236 
0-1398 
0*1359 
0*1421 
0*1483 
0*1544 
0*1605 
0*1667 
0-1738 
0*1790 


0<».  4   0°.  8   1°.  3   1°.  6  3<».  0 
12        34        85        47        69 


Past  II. — Mercury  and  Bras*. 


Height  of  the  Barom.  in  Inches. 


38  In. 


0*0088 
0*0138 
0*0188 
0*0338 
0*0388 
0*0338 
0*0388 
0*0438 
0*0488 
0*0538 


0-0588 
0*0638 
0*0688 
0-0738 
0*0788 
0*0838 
0*0888 
0*0938 
0*0988 
0*1037 


0*1087 
0*1137 
0*1187 
0*1237 
0*1286 
1336 
1386 
1435 
1485 
1535 


39  In. 


0*0091 
0*0143 
0*0194 
0*0346 
0*0398 
0*0350 
0*0403 
0*0454 
0*0506 
0*0558 


0*0609 
0*0661 
0*0713 
0*0765 

0*0817 
0*0868 
0*0930 

0*0971 
0*1033 
0*1076 


0*1136 
0*1178 
0*1339 
0*1381 
0*1333 
0*1384 
0*1435 
0*1486 
0*1538 
0*1689 


so  In. 


0*0094 
0*0148 
0*0301 
0*0366 
0*0309 
0*0363 
0*0416 
0*0470 
0*0633 
0*0577 


0*0630 
0*0684 
0*0738 

0*0791 
0*0846 
0*0898 
0*0951 
01006 
0*1058 
0*1113 


0*1166 
0*1318 
0-1373 
0*1336 
0-1.378 
0*1433 
0*1486 
0*1638 
0*1501 
0*1644 


31  In. 


0*0097 
0*0153 
0*0208 
0*0363 

0*0319 
0*0374 
0*0430 
0*0485 
0*0641 
0*0596 


0-0653 

0*0707 
0*0763 
0*0818 
00873 
0*0938 
0*0983 
0*1039 
0*1094 
0*1149 


0*1304 
0*1369 
0*1314 
0*1369 
0*1424 
0*1479 
0*1534 

0'1589 
0*1644 

0*1099 


3 

6 

7 

9 

11 

13 

14 

16 

17 

19 


21 
33 
35 
86 
38 
30 
S3 
84 
36 
38 


40 
43 
44 

46 

47 
49 
61 
53 
54 
66 


O**.  4  O**.  8  1°.  3  1°.  6  3®.  0 
10   31    31   43   53 


JWmt  Galbraith*8  Tables. 


39 


BAR 


BASE  COURT. 


BAS 


The  atmosphere  is  supposed  to 
extend  to  ahout  the  height  of  50 
miles ;  and  its  density  to  diminish 
from  the  smfisoe  of  the  globe  up- 
wards, in  a  geometrical  ratio. 

Thus,  when  observations  are  made 
on  land,  above  the  level  of  the  sea, 
a  correction  is  required  for  altitude, 
since  the  weight  of  the  atmosphere 
diminishes  as  we  ascend.  It  is 
owing  to  this  that  we  are  enabled 
to  determine  the  height  of  moun- 
tains by  barometers ;  and  that  aero- 
nauts compute  the  altitude  to  which 
they  ascend  in  balloons. 

If  any  fluid  in  a  cup  be  put  into 
rapid  circular  motion,  we  should 
have  a  representation  of  the  form 
that  portion  of  the  atmosphere  as- 
sumes which  is  VTithin  the  limits  of 
a  storm ;  the  most  depressed  part 
of  the  fluid  would  represent  the 
centre  of  the  gale  where  the  atmo- 
spheric pressure  is  the  least. 

The  principle  of  the  barometer 
shoyld  be  explained  in  all  works 
on  navigation,  and  in  all  schools 
where  navigation  is  taught 

Barm,  in  heraldry,  a  degree  of  no- 
bUity  next  to  a  viscount 

Baronet  J  in  heraldry,  the  lowest  de- 
gree of  honour  that  is  hereditary 

Baroscope,  an  instrument  for  proving 
the  weight  of  the  atmosphere 

Barque,  a  three-masted  vessel  having 
her  fore  and  main  masts  rigged  like 
ft  ship's,  and  her  mizen-mast  like 
the  main-mast  of  a  schooner,  with 
no  sail  upon  it  but  a  spanker 

Barra,  in  the  middle  ages,  a  tower  or 
bar  at  one  end  of  a  bridge 

Barrack,  a  building  for  the  lodgment 
of  soldiers 

Barraly,  in  heraldry,  the  field  divided 
barwise,intoseveral  parts,  sideto  side 

Barrel,  in  machinei-y,  is  a  term  ap- 
plied generally  to  anything  hollow 
and  cylindrical 

Barrow,  in  mining,  a  heap  of  dead 
attle,  rubbish,  &c. 

Barrows,  or  tumuli,  monuments  of 
the  greatest  antiquity,  raised  as  se- 
pulchres for  the  interment  of  the 
great 

40 


Barrukt,  in  heraldry,  the  fourth  part 
of  the  bar,  or  one-half  the  closet 

Barry,  in  heraldry,  is  when  an  escut- 
cheon is  divided  barwise,  or  into 
any  number  of  compartments 

Barry-bendy,  in  heraldry,  is  when 
the  escutcheon  is  divided  evenly 
barwise  and  bendwise 

Barry-pily,  in  heraldiy,  is  when  a 
coat  is  divided  by  several  lines 
drawn  obliquely  from  side  to  side, 
where  they  form  acute  angles 

Bare,  straight  pieces  of  timber  or 
metal  that  run  across  from  one 
part  of  a  machine  to  another 

Bartisan,  in  architecture,  the  small 
overhanging  turrets  which  project 
from  the  angles  on  the  top  of  a 
tower,  or  from  the  parapet  or  other 
parts  of  a  building 

Bartisan,  a  wooden  tower ;  a  tnrret 
on  the  top  of  a  house,  castle,  or 
church  tower 

Barton,  a  manor-house,  or  out-house 

Bar  Wood,  is  an  African  wood,  four 
to  five  feet  long.  It  is  used  as  red 
dip  wood,  used  for  ■violin  bows, 
ramrods,  and  turning 

Barytes,  a  heavy  mineral  substance, 
found  in  copper  mines,  and  for- 
merly named '  ponderous  spar' 

BasaU,  a  variety  of  trap  rock,  usually 
of  a  dark  green  or  brownish  black 
colour,  composed  of  augite  and  fel- 
spar, with  some  iron  and  olivine 

BasaUea,  a  heavy,  hard  stone,  chiefly 
black  or  greenish,  consisting  oi 
prismatic  crystals,  the  number  of 
whose  sides  is  uncertain 

Basanite,  a  variety  of  schistose  horn- 
stone,  called  also  Lydian  stone 

Base  of  a  figure,  in  geometry,  denotes 
the  lowest  part  of  its  perimeter 

Base  of  a  conic  section,  is  a  rigW 
line  in  the  parabola  and  hyperbola 
formed  by  the  common  intersection 
of  the  cutting  plane  and  the  base 
of  the  cone 

Base,  in  architecture,  the  lower  part 
or  member  of  a  column,  on  which 
the  shaft  stands 

Base-court,  the  outer  or  lower  yard 
of  a  castle,  appropriated  to  stables, 
offices,  &c. 


BAS 


BASILICA. 


BAS 


Base-line,  in  perspective)  the  common 
section  of  a  picture  and  the  geo- 
metrical plane 

Base-Une,  in  surveying,  a' line,  mea- 
sured with  the  greatest  possible 
exactness,  on  vehich  a  series  of  tri- 
angles are  constructed,  in  order  to 
determine  the  position  of  objects 
and  places.  The  measurement  of 
degrees  of  the  meridian,  for  the 
porpose  of  ascertaining  the  size  of 
the  earthy  have  been  undertaken 
in  various  countries,  with  extreme 
accuracy.  The  arc  measured  by 
the  French  extended  from  Dunkirk 
to  the  southernmost  point  of  the 
Balearic  Islands,  including  120°, 
22^,  14'^  having  its  centre  half- 
way between  the  equator  and  the 
north  pole.  Another  survey  of  this 
kind  was  performed  on  a  part  of 
the  shore  of  Pennsylvania,  which 
happens  to  be  so  straight  and  level 
as  to  admit  of  a  line  of  more  than 
100  miles  being  measured  directly 
without  tiiangulation.  Very  long 
lines  have  also  been  measured  (tri- 
gonometiically)  by  order  of  the 
English  government,  both  at  home 
and  in  India,  the  mean  result  of 
which  makes  the  earth's  axis  7898 
miles,  5  furlongs,  16  yards,  and  the 
diameter  of  the  eq^tor  7924  miles 
7  forlongs 

Basement^  the  lower  story  or  floor  of 
a  building;  the  story  of  a  house 
below  the  level  of  the  ground 

Batements,  As  an  alternative  for 
employing  orders  upon  orders,  the 
ground  floor  is  made  to  assume  the 
appearance  of  a  basement,  and  the 
order  that  decorates  the  principal 
story  placed  thereupon:  in  such 
cases  the  basements  should  not  be 
higher  than  the  order  it  supports, 
nor  lower  than  one-half  the  height 
of  the  order ;  but  if  a  basement  be 
mtroduced  merely  for  the  purpose 
of  raising  the  principal  or  ground- 
floor,  it  may  be  three,  four,  five,  or 
six  feet  high,  at  pleasure. 

These  basement  stories  are  gene- 
niUy  in  rock-worked  or  plain  rus- 
tics; and  in  no  case  should  the 


height  of  a  rustic  course  be  lesi 
than  one  module  of  the  order  rest- 
ing on  the  basement,  nor  should  i1 
ever  much  exceed  it :  their  joints, 
if  tquare,  ought  not  to  be  broadei 
than  one-eighth  of  the  height  oi 
the  rustic,  nor  narrower  than  one- 
tenth,  and  their  depth  should  equal 
their  breadth;  if  chanrfered,  the 
whole  joint  may  be  one-quarter  to 
one-third  the  height  of  the  rustic, 
the  joint  being  always  right-angled 
When  the  basement  is  high,  it  is 
sometimes  crowned  with  a  cornice, 
but  a  platband  is  more  commonly 
used. — GwiU. 

Basenet,  a  helmet 

Base-plate,  the  foundation  plate  of  an 
engine 

Basil,  that  angle  the  edge  of  a  tool  is 
ground  to 

Basilica,  in  the  time  of  the  Romans, 
a  public  hall  or  court  of  judicature. 
After  the  conversion  of  the  em- 
peror Constantine  to  Christianity, 
these  edifices  were  converted  into 
Christian  churches  The  BasUioB 
of  the  Romans  were  the  types  from 
which  the  early  Christian  places  of 
worship  were  taken ;  and  the  ruins 
of  these  buildings  were  the  chief 
materials  used.  In  several  instances 
the  columns  that  divide  the  centre 
part  of  the  church  from  the  aisles 
have  been  taken  frx)m  other  edifices, 
either  on  account  of  the  want  of 
artists  capable  of  executing  any 
thing  equal  to  them,  or  the  haste 
with  which  they  were  erected. 
The  expedient  that  was  adopted 
tends  to  show  that  proportion  was 
not  considered;  some  columns  were 
reduced  from  their  former  height, 
and  others  mounted  on  pedestals 
to  suit  the  purposes  to  which  they 
were  applied.  Besides  this  total 
disregard  to  proportion  in  the  shafts 
of  the  columns,  capitals  and  bases 
were  applied  without  any  consider- 
ation to  their  fitness.  The  heathen 
basihcsB,  generally  situated  in  the 
forums,  were  of  rectangular  form, 
and  divided  into  three  or  five  parts 
by  rows  of  columns  parallel  to  the 


■AMCb 


BAS 


BASSO.RILIBVO. 


BAT 


length  of  the  huilding;  another 
colonnade  at  the  extremity  crossed 
the  former  at  right  angles,  and  in 
the  middle  of  the  end  wall  was  a 
semicircular  recess,  in  which  was 
situated  the  tribune  of  the  judge. 
These  basilicie  had  likewise  galle- 
ries oyer  the  aisles,  in  which  com- 
mercial or  other  business  was  trans- 
acted ;  but  in  the  Christian  churches 
this  was  appropriated  to  the  wo- 
men, who  (as  in  the  Jewish  syn- 
agogues) were  not  allowed  to  join 
with  the  men  in  the  lower  parts  of 
the  building.  These  galleries  were 
omitted  in  the  after  basilicse,  and 
one  of  the  aisles  was  retained  solely 
for  their  use.  Six  of  the  principid 
churches  or  basilicae  at  Rome  are 
attributed  to  the  zeal  of  Gonstan- 
tine.  The  basilicae  of  St.  John  de 
Lateran,  St.  Peter,  St.  Laurentius, 
St.  Paul,  St.  Agnes,  and  St.  Ste- 
phen were  built  by  him,  besides 
the  baptisterium  that  bears  his 
name 

BasiUculat  a  shrine,  oratory,  or  ceno- 
taph 

Basifu  and  ewers.  In  early  times, 
before  the  cleanly  custom  of  using 
a  fork  was  practised,  the  hands 
were  frequently  washed  during  din- 
ner :  a  basin  and  ewer  were  handed 
for  that  purpose  by  an  attendant. 
At  the  feast  given  by  Henry  VIII. 
to  the  French  ambassadors,  there 
were  three  ewry  boards;  one  for 
the  king,  another  for  the  queen, 
and  the  third  for  the  princes,  &c. 

Basset,  The  basset  or  outcrop  means 
the  emergence  at  the  surface  of  the 
different  mineral  strata  from  be- 
neath each  other 

Bass-relief  or  Basso-rilievo,  a  species 
of  low  sculpture,  the  figures  of 
which  do  not  stand  out  from  the 
ground  in  their  full  proportion 

Bastard  stucco,  a  three-coated  plaster, 
the  first  generally  roughing  in  or 
rendering ;  the  second  floating,  as 
in  trowelled  stucco ;  but  the  finish- 
ing coat  contains  a  little  hair  be- 
sides the  sand:  it  is  not  hand- 
floated,  and  the  trowelling  is  done 


with  less  labour  than  what  is  called 
trowelled  stucco 

Bastard-toothed  file,  in  smithing,  that 
employed  after  the  rubber 

Bastard-wheel,  a  flat  bevil-wheel,  or 
one  which  is  a  near  approach  to  a 
spur-wheel 

Bastida,  in  the  twelfth  century,  a 
place  of  defence,  a  fortress 

Bastile,  a  prison;  a  castle,  tower,  fort- 
ress, or  any  place  of  defence 

Bastion,  a  rampart,  bulwark,  or 
earthen  mound 

Batardeau,  a  coffer-dam,  or  case  of 
piling  without  a  bottom,  for  build- 
ing  the  piers  of  a  bridge 

Batch,  in  mining,  a  certain  quantity 
of  ore  sent  to  the  surface  by  any 
pair  of  men 

Bateau,  a  light  boat,  long  in  propor- 
tion to  its  breadth 

Bath,  a  receptacle  of  water,  in  which 
to  plunge,  wash,  or  bathe  the  body. 
Among  the  Romans,  baths  were 
erected  both  in  magnificence  of 
style  and  purpose,  many  of  them  of 
great  architectural  beauty.  In  later 
times  the  bath  was  always  used  by 
the  Romans  before  they  went  to 
their  supper.  The  rich  generally 
had  hot  and  cold  baths  in  their 
own  houses ;  and  it  was  not  till  the 
time  of  Augustus  that  the  baths 
assumed  an  air  of  grandeur  and 
magnificence.  The  situation  chosen 
for  baths  ought  to  be  sheltered 
from  the  north  and  north-east. 
The  caldaiia  and  tepidaria  should 
be  made  to  receive  their  light 
from  the  west;  or,  should  local 
circumstances  not  admit  of  this 
disposition,  they  may  both  be  made 
to  face  the  south,  because  the  ge- 
neral time  of  bathing  is  frt)m  mid- 
day until  sunset.  One  thing  neces- 
sary to  be  observed  is,  that  the 
caldaria  of  that  division  of  the  bath 
which  is  appropriated  to  the  women 
should  be  contiguous  to  that  exclu- 
sively used  by  the  men,  and  have 
the  same  aspect;  for  then  the  cop- 
pers of  both  may  be  heated  from 
the  same  furnace.  Three  brazen 
vessels  are  fixed  over  the  furnace, 


42 


.   ■   f    r   ^      ■  j^    ..        -      » ^         »    _-.  —     ^^^«  ,  -*    ...   ,    - 


'  *  1  'iJ  ^i^w^^a^^^^fcfci 


BAT 


BAY* 


BAY 


which  are  severally  called  ealda- 
rium,  tepidarium,  and  frigidarium : 
they  are  so  arranged,  that  whaMyer 
heated  water  is   taken   from  the 
first,  is  replaced   by  warm  water 
£rom  the  second,  the  deficiency  of 
which  is  supplied,  in  a  similar  man- 
ner, from  the  thL^.     The  concave 
coTerings  of  the  small  tubes  of  both 
baths  are  likewise  heated  from  the 
same  furnace.   The  insulated  stages 
of  the  caldaria  are  thus  constructed: 
the  floor  is  made  inclining  towards 
the  furnace,  so  that  if  a  ball  were 
placed  upon  any  part  of  it,  it  would 
not  remain  at  rest,  but  take  a  direc- 
tion towards  the  mouth ;  by  which 
means  the  flame  will  more  easily 
pervade  the  interval  between  the 
floors,  which  is  paved  with  tiles  a 
foot  and  a  half  square:  upon  the 
floor,  earthen  props,  eight  inches 
each  way,  are  arranged  at  such  in- 
tervals as   to   receive  upon  them 
square  tiles  two  feet  in  length :  the 
props  are  two  feet  in  height;  the 
tiles  which  form  them  are  cemented 
with  clay  and  hair  mixed  together. 
The  square  tiles  which  they  sup- 
port form  the  substratum  of  the 
pavement  of  the  caldaria 

Bath  stonCf  Bath  oolite ;  minute  glo- 
bules, cemented  together  by  yel- 
lowish earthy  calcareous  matter; 
is  much  used  in  building,  but  not 
a  lasting  material.  It  is  soft  when 
quarried,  but  hardens  by  exposure 
to  the  air 

BatifoUum,  a  moveable  wooden  tower 
used  by  besiegers  in  attacking  a 
fortress 

Batten,  in  carpentry,  a  scantling  of 
wooden  stuflT,  from  two  to  four 
inches  broad,  and  about  one  thick, 
principally  used  for  wainscot,  on 
which  also  are  bradded,on  the  plain 
boards,  also  batten  doors,  those 
which  resemble  vmnscot  doors, 
but  are  not  so;  for  in  wainscot 
doors  the  panels  are  grooved  in 
the  framing 

Battens,  nautical,  thin  strips  of  wood 
put  around  the  hatches  to  keep  the 
tarpaulin  down;    also   put   upon 

43  ~ 


rigging  to  keep  it  from  Chafing. 
A  large  batten  widened  at  the  end, 
and  put  upon  rigging,  is  called  a 
Scotchman 
Batter,  to  displace  a  portion  of  the 
iron  of  any  bar  or  other  piece  by 
the  blow  of^a  hammer,  so  as  to 
flatten  or  compress  it  inwardly, 
and  spread  it  outwardly  on    all 
sides  around  the  place  of  impact 
Batter,  a  term  applied  to  walls  built 
out  of  the  upright,  or  gently  sloping 
inwards;  wharf  walls  and  retaining 
walls  built  to  support  embankments 
Batter,  the  leaning  back  of  the  up- 
per part  of  the  face  of  a  wall,  so  as 
to  make  the  plumb-line  fall  within 
the  base 
Battery,  in   electricity,  a  combina- 
tion of  coated  surfaces  of  glass, 
commonly  jars,  so  connected  to- 
gether that  they  may  be  charged 
at  once  and  discharged  by  a  com- 
mon conductor 
Battlement,  an  open  or  interrupted 
parapet  on  the  roof  of  a  building ; 
a  parapet  with  embrasures 
Bauffium,  an  out-house  or  domestic 

office 
Baidk,  a  piece  of  foreign  fir,  or  deal, 
from  8  to  16  inches  square,  being 
the  trunk  of  a  tree  of  that  species 
of  wood;  generally  brought  to  a 
square  for  the  use  of  building 
Bawk,  a  cross  beam  in  the  roof  of  a 
house  which  unites  and  supports 
the  rafters ;  a  tie-beam 
Bay,  a  division  of  a  roof  or  vaulting 
of  a  building,   consisting  of  the 
space  between  the  beams  or  arches. 
A  part  of  a  window  between  the 
mullions  is  often  called  a  bay  or 
day 
Bay,  in  plastering,  the  space  between 
the  skreeds,  prepared  for  regulating 
and  working  the  fioating-rule 
Bay  of  Joists,  the  joisting  between 
two  binding  joists,   or    between 
two   girders  when  binding  joists 
are  not  used 
Bay  o/ roofing,  the  small  rafters  and 
their  supporting  purlins  between 
two  principal  rafters 
Bay-salt,  salt  obtained  by  evaporating 


BAY 


BEAMS. 


BEAi 


sea-water  in  shallow  ponds  by  the 
heat  of  the  sun ;  is  of  a  dark  grey 
colour,  and  contains  iodine 

Bay  tree,  a  native  of  Italy  and  Greece; 
grows  to  the  height  of  thirty  feet, 
and  is  an  aromatic  wood 

Aiy-irtn^otc',  an  oriel  window:  a  win- 
dow jutting  outwards;  frequently 
called  bow-window 

Bazaar t  a  market-place 

Beacon,  a  post  or  buoy  placed  oyer  a 
shoal  or  bank,  to  warn  vessels  off: 
also  a  signal-mark  on  land 

Beacon,  an  eminence  on  which  a 
tower  is  placed,  with  a  light  to  de- 
note the  approach  of  danger 

Bead,  a  small  globular  ornament  used 
in  ancient  and  modem  architecture 

Bead  and  BtUt  work,  in  carpentiy, 
framing  in  which  the  pannels  are 
flush,  having  beads  stuck  or  run 
upon  the  two  edges,  the  gi-ain  of  the 
wood  being  in  the  direction  of  them 

Bead  and  quirk,  a  bead  stuck  on  the 
edge  of  a  piece  of  stuff,  flush  with 
its  surface 

Bead-butt  and  sguare'Work,  framing 
with  bead  and  butt  on  one  side, 
•nd  square  on  the  other ;  is  used 
in  doors 

Bead-house,  a  dwelling-place  for  poor 
religious  persons 

Bead-plane,  is  a  moulding  plane  of  a 
semi-cylindric  contour,  and  is  ge- 
nerally used  in  sticking  a  moulding 
of  the  same  name  on  the  edge,  or 
on  the  side  close  to  the  arris 

Beak,  the  crooked  end  of  a  piece  of 
iron,  to  hold  any  thing  fast 

Beak,  a  small  pendent  fillet,  forming 
a  channel  behind,  to  prevent  water 
from  running  down  the  lower  bed 
of  the  cornice 

Beak-head,  a  small  platform  at  the 
forepart  of  the  upper  deck  in  large 


Beak  iron,  the  conic  part  of  the  an- 
vil, with  its  base  attached  to  the 
side,  and  its  axis  horizontal 

Beaking-joint,  is  the  joint  formed  by 
themeetingofseveralheading  joints 
in  one  continued  line,  wluch  is 
sometimes  the  case  in  folded  floors 

Beam,  a  horizontal  piece  of  iron  or 


timber,  used  to  resist  a  force  or 
weight,  as  a  tie-beam,  where  it  acts 
as  a  string,  or  chain,  by  its  ten-i 
sion;  as  a  collar-beam,  where  it' 
acts  by  compression;  as  a  Inres- 
summer*  where  it  resists  a  trans- 
verse insisting  weight 
Beam,  in  steam-engine,  a  large  lever 
turning  upon  a  centre,  and  forming 
the  medium  of  communication  be- 
tween the  piston-rod  and  the  crank 
shaft 
Beama.  Forms  of  Beams.  In  the 
construction  of  beams,  it  is  ne- 
cessary that  their  form  should  be 
such  that  they  wUl  be  equally 
strong  throughout;  or,  in  other 
words,  that  they  will  offer  an  eqnsl 
resistance  to  fracture  in  all  their 
parts,  and  will,  therefore,  be  equally 
liable  to  break  at  one  part  of  their 
length  as  at  another. 

If  a  beam  be  fixed  at  one  end 
and  loaded  at  the  other,  and  the 
breadth  uniform  throughout  its 
length,  then,  that  the  beimi  may  be 
equally  strong  throughout,  its  form 
must  be  that  of  a  parabola. 

This  form  is  generally  used  in 
the  beams  of  steam-engpines ;  and, 
in  double-acting  steam-engines,  the 
beam  is  strained  sometimes  from 
one  side,  and  sometimes  frt>m  the 
other;  therefore,  both  the  sides 
should  be  of  the  same  form. 

Mr.  Emerson  gives  the  load  that 
may  be  sdPely  borne  by  a  square 
inch  rod  of  each  of  the  following : 

Ibi.  avoird. 

Iron  rod,an  inch  square  1  ^g  ^qq 

willbear    .    .    .     J  ' 

Brass 35,600 

Hempen  rope     .    .    •  19,600 

Ivory 15,700 

Oak,  box,  yew,  plum- 1  y  g^^ 

tree      .    .    .    .     j  * 

Elm,  ash,  beech     .    .  6,070 

Walnut,  plum    .    •    •  5,360 
Bed  fir,  holly,  elder,! 
plane,  crab    .    .     J 

Cherry,  hazel     .    .    .  4,760 

Alder,  asp,  birch,  willow  4,290 

l^ad 430 

Freestone 914 


5,000 


44 


BEA 


BEAMS,  FORMS  OF. 


BEA 


He  also  gives  the  following  prac- 
tical rule,  yiz.,  That  a  cylinder,  the 
diameter  of  which  U  d  inches, 
loaded  to  one-fourth  of  its  absolute 
strength,  will  cany  as  follows : 

cwt< 

Iron  135  X  cP 

Good  rope .  •  •  .  22  x  tP 
Oak  ...•-.  14  X  <^ 
Fir 9  X  d« 

Also  he  says,  that  a  cylindric  rod 
of  good  clean  fir,  of  an  inch  cir- 
cumference, drawn  in  length,  will 
bear  at  its  extremity  400  lbs. ;  and 
a  spear  of  fir,  2  inches  diameter, 
will  hear  about  7  tons,  but  not 
more. 

A  rod  of  good  iron,  of  an  inch 
circumference,  will  hear  nearly  3 
tons  weight. 

A  good  hempen  rope,  of  an  inch 
circumference,  will  bear  1000  lbs. 
being  at  its  extremity. 

Mr.  Barlow  gives  the  following 
table  as  a  mean  derived  from  his 
experiments,  on  the  strength  of 
direct  cohesion  on  a  square  inch  of 
the  following : 

fts. 
Box  is  about ....    20,000 

Ash 17,000 

Teak 15,000 

Fir 12,000 

Beech 11,500 

Oak 10,000 

Pear 9,800 

Mahogany      ....      8,000 

Transversb  Strength  of 
Beams,  etc.  The  transverse 
strength  of  rectangular  beams,  or 
the  resistance  which  they  offer  to 
fracture,  is  as  the  breadth  and 
square  of  the  depth:  therefore,  if 
two  rectangular  beams  have  the 
same  depth,  their  strengths  are  to 
each  other  as  their  breadths ;  but 
if  their  breadths  are  the  same, 
then  their  strengths  are  to  each 
other  as  the  squares  of  their  depths. 

The  transverse  strengths  of 
square  beams  are  as  the  cubes  of 
the  breadths  or  depths.  Also,  in 
cylindrical  beams,  the  transverse 

~45 


strengths  are  as  the  cubes  of  the 
diameters. 

Thus,  if  a  beam  which  is  one  foot 
broad  and  one  foot  deep  support  a 
given  weight,  then  a  beam  of  the 
same  depth,  and  two  feet  broad, 
will  support  double  the  weight. 

But  if  a  beam  be  one  foot  broad 
and  two  feet  deep,  it  will  support 
four  times  as  much  as  a  beam  one 
foot  broad  and  one  foot  deep. 

If  a  beam  one  foot  square,  sup- 
port a  given  weight,  then  a  beam 
two  feet  square  will  support  eight 
times  as  much.  Also,  a  cylinder 
of  two  inches  in  diameter  will  sup- 
port dglit  times  as  much  as  a  cy- 
linder one  inch  in  diameter. 

The  following  table  of  data  is 
extracted  from  tables  in  Barlow's 
Essay: 

Teak 2,462 

English  oak    ....    1,672 

Canadian  do 1,766 

Dantzic    do 1,457 

Adriatic  do 1,383 

Ash 2,026 

Beech 1,556 

JSlm 1,013 

Pitch  pine 1,632 

Red  pine 1,341 

New  England  fir  .    .    .    1,102 

Riga  fir 1,108 

Mar  Forest  fir.    .    .    .    1,262 

„     Larch 1,127 

Beam-ends,  A  ship  is  said  to  be  on 
her  beam-ends  when  she  inclines 
very  much  on  one  side,  so  that  her 
beamsapproach  to  a  vertical  position 
Beam  engincy  generally  a  land  en- 
gine, which  has  the  top  of  the  pis- 
ton-rod connected  to  one  end  of  a 
lever  or  beam:  by  a  contrivance 
called  a  parallel  motion,  the  beam 
vibrates  upon  a  central  ads,  and 
communicates  the  motion  of  the 
piston  to  the  crank  by  means  of  a 
connecting-rod  attached  to  the 
other  end  of  the  beam,  and  also 
gives  motion  to  the  various  parts 
Beam-fillingi  the  brickwork,  or  ma- 
sonry, brought  up  from  the  level 
of  the  under  to  the  upper  sides  of 
the  beams 


BEA 


BED-MOULDINGS. 


BED 


Beam  gudgeorUf  the  bearings  on  the 
centre  of  the  beam,  or  the  central 
pivot  upon  which  it  vibrates 

Beam  of  a  balancet  the  horizontal 
piece  of  iron  from  the  ends  of 
which  the  scales  are  suspended 

BeamSf  in  naval  architecture,  strong 
thick  pieces  of  timber  stretching 
across  the  ship  from  side  to  side,  to 
support  the  decks :  they  are  sus- 
tained at  each  end  by  thick  planks 
in  the  ship's  side,  called  clamps, 
upon  which  they  rest 

BeareTf  any  thing  used  by  way  of 
support  to  another  weight 

Bearer  J  in  turning,  that  part  of  the 
lathe  which  supports  the  puppets 

Bearinffi  the  distance  that  a  beam 
or  rafter  is  suspended  in  the  clear : 
thus,  if  a  piece  of  timber  rests  upon 
two  opposite  waUs,  the  span  of  the 
void  is  called  the  bearing,  and  not 
the  whole  length  of  the  timber 

Bearinfft  that  part  of  a  shaft  or 
spindle  which  is  in  contact  with 
the  supports 

Bearing^  a  word  for  delineating  an 
antique  plaster  figure.  It  is  gene- 
rally said,  if  the  drawing  of  a  figure 
has  not  the  same  bearing  or  angles 
of  inclination  as  the  original  pos- 
sesses, it  is  out  in  all  its  bearings 

Bearing^  in  heraldry,  the  figures  on 
a  coat  of  arms ;  a  coat  of  arms  in 
general 

Bearing,  the  direction  of  an  object 
fit)m  the  person  looking.  In  ship- 
ping, the  bearings  of  a  vessel  are  the 
widest  part  of  her  below  the  plank- 
sheer  ;  that  part  of  her  hull  which 
is  on  the  water  line  when  she  is  at 
anchor  and  in  her  proper  trim 

Beat  away,  in  mining,  to  excavate, 
usually  applied  to  hard  ground 

Beatingy  in  navigation,  the  operation 
of  making  progress  at  sea  against 
the  wind 

Beaufet,  a  cupboard  or  niche 

Beau  ideal,  va.  painting,  that  beauty 
which  is  freed  from  the  deformity 
and  the  peculiarity  found  in  nature 
in  all  individuals  of  a  species 

Beauty,  in  architecture,  consists  of 
the  following  qualities :  magnitude 

46~ 


and  strength,  order  and  harmony, 
richness  and  simplicity ;  Constnic- 
tion,  in  which  the  cMcf  requisites 
are  magnitude  and  strength,  order 
and  harmony;  Decoration,  whose 
requisites  are  richness  or  simplicity, 
accprding  to  the  nature  of  the  com- 
position 

Becalm,  to  intercept  the  wind  by  al- 
ternate tacks 

Becket,  a  piece  of  rope  placed  so  as 
to  confine  a  spar  or  another  rope ; 
a  handle  made  of  rope  in  the  form 
of  a  circle 

Beconage,  dues  levied  for  the  mainten- 
ance of  beacons 

Bed  of  a  brick,  the  horizontal  sur- 
faces as  disposed  in  a  wall 

Bed,  a  term  used  in  masonry  to  de- 
scribe the  direction  in  which  the 
natural  strata  in  stones  lie;  it  is 
also  applied  to  the  top  and  bottom 
surface  of  stones  when  worked  for 
building 

Bed,  in  mining,  a  seam  or  horizontal 
vein  of  ore 

Beds  of  a  stone  are  the  parallel  sur- 
faces which  intersect  the  face  of  the 
work  in  lines  parallel  to  the  horizon 

Beds  and  Bedding.  Feather-beds, 
bolsters,  and  pillows  filled  with 
feathers  and  down,  with  mattresses 
and  every  other  comfort  of  this 
kind,  seem  to  have  been  as  well 
known  to,  and  enjoyed  by,  the  su- 
perior orders  of  society  three  cen- 
turies ago,  as  they  are  now.  Direc- 
tions are,  however,  mentioned  as 
having  been  given  in  the  reign  of 
Henry  VIII.  "to  examine  every 
night  the  straw  of  the  king's  bed, 
that  no  daggers  might  be  con- 
cealed." 

Beds  (trussing)  were  beds  which 
packed  into  chests,  for  travelling; 
and,  considering  the  frequent  re- 
movals, these  must  have  been  the 
most  convenient  kind.  John  of 
Ghent  seems  to  have  always  slept 
in  such  beds,  as  by  his  will  it  ap- 
pears that  he  demised  to  his  wife 
all  the  beds  made  for  his  body, 
"  called  in  England  trussing-beds;" 
and  the  "  best  chambers"  of  both 


B£D 


BELFRY. 


BEL 


Master  Permor  and  Sir  Adrian  Fos- 
kewe  had  trussing-beds 

Bed-chamberg,  in  Tudor  times.  The 
furniture  of  these  apartments,  in 
great  houses,  was  of  the  same  gor- 
geous character  as  that  in  the  chief 
rooms ;  and  the  paraphernalia  of  an 
ancient  dressing-table  yielded  only, 
in  the  splendour  and  costliness  of 
plate,  to  the  cupboard  of  the  great 
chamber,  or  the  altar  of  the  chapel. 
Like  the  hall,  the  state  bed-cham- 
ber had  a  high  place,  on  which 
were  placed  the  *  standing  bed'  and 
the  'truckle-bed ' :  on  the  former  lay 
the  lord,  and  on  the  latter,  his  at- 
tendant 

Beddem,  a  refectory 

Beddrng-stonef  used  in  bricklaying,  a 
straight  piece  of  marble :  its  use  is 
to  try  the  rubbed  side  of  the  brick ; 
first,  to  square,  to  prove  whether  the 
smrface  of  the  brick  be  straight;  se- 
condly, to  fit  it  upon  the  leading  skew- 
back,  or  leading  end  of  the  arch 

Bed-nunddmgs.  This  may  be  under- 
stood as  a  oollectiYe  term  for  all 
the  mouldings  beneath  the  corona 
or  principal  projecting  member  of 
a  cornice,  which,  without  bed- 
mouldings,  would  appear  too  much 
like  a  mere  shelf 

Bed-platej  the  foundation  plate  of  a 
marine  or  a  direct  action  engine 

^ed:r/«ad^,  in  Tudor  times.  The  posts, 
head-boards,  and  canopies,  or  sper- 
vers  of  bedsteads  were  curiously 
wrought  and  carved  in  oak,  walnut, 
box,  and  other  woods,  and  variously 
painted  and  g^t.  Ginger-colour, 
hatched  with  gold,  was  a  favourite 
style,  but  purple  and  crimson  were 
also  used  in  their  decorations 

Beech,  a  species  of  timber  very  much 
wed  l^  artificers ;  while  young,  it 
possesses  great  toughness,  and  is  of 
awhitecolour:  the  cohesive  strength 
is  12,225  fts.  weight,  which  will  tear 
asunder  a  piece  of  this  timber  one 
square  indi 

Beech  tpood,  common  in  Buckingham- 
shire and  Sussex  as  the  best ;  about 
fifty  feet  high  and  thirty  inches  in 
diameter ;  white,  brown,  and  black 


colour :  it  is  used  for  piles  in  wet 
foundations;  is  used  also,  for  its 
uniform  texture  and  closeness,  in 
in-door  works,  as  the  frames  of 
machines,  bedsteads,  and  furniture; 
also  for  planes,  tools,  lathe-chucks, 
keys,  cogs  of  machinery,  brushes, 
handles,  &c 

Beef  wood,  red-coloured  wood,  gene- 
nerally  applied  to  Botany  Bay  oak 

Beer-drawing  macJwnee  are  contriv- 
ances by  means  of  which  beer  is 
drawn  up  from  the  barrel  or  cask 

Beett  pieces  of  plank  bolted  to  the 
outer  end  of  the  bowsprit,  to  score 
the  fore-top  mast  stays  through 

Beetle,  or  Maui,  a  large  mallet  to 
knock  the  comers  of  framed  work, 
and  to  set  it  in  its  proper  position : 
the  handle  is  about  three  feet  in 
length 

Brfore  the  learn,  in  naval  architec- 
ture, is  an  arch  of  the  horizon, 
comprehended  between  a  line  which 
crossesaships'leng^h  at  right  angles, 
and  some  object  at  a  distance  be- 
fore it ;  or  between  the  line  of  the 
beam,  and  that  point  of  the  com- 
pass which  she  stems 

Belay,  to  make  a  rope  fast  by  turns 
round  a  pin  or  coil,  without  hitch- 
ing or  seizing  it 

Belfry,  that  part  of  the  tower  of  a 
church  which  contains  bells 

Bell.  The  body  of  a  Corinthian  or  Com- 
posite capital,  supposing  the  foliage 
stripped  off,  is  called  the  bell ;  the 
same  is  applied  also  to  the  early 
English  and  other  capitals  in  Go- 
thic architecture  which  in  any  de- 
gree partake  of  this  form 

BeU,  a  metallic  instrument  rung  in  the 
belfry  of  a  church  for  the  attend- 
ance of  divine  worship,  and  upon 
occasions  of  rejoicing;  composed 
of  three  parts  of  copper  and  one  of 
tin,  called  bell-metal 

BeU' crank,  a  bent  lever,  used  for 
changing  a  vertical  into  a  horizon- 
tal motion 

BeU-gdble,  a  term  applied  to  the  gable 
of  a  rehgious  edifice,  having  a  plain 
or  ornamental  niche  for  the  recep- 
tion of  one  or  more  bells 


47 


BEL 


BELLOWS. 


BBT 


Bettowst  the  instrument  for  blowing 
the  fire,  with  an  internal  cavity  so 
contrived  as  to  be  of  greater  or  less 
capacity  by  reciprocating  motion, 
and  to  draw  in  air  at  one  place  while 
the  capacity  is  upon  the  increase, 
and  discharge  it  by  another  while 
upon  the  decrease.  The  bellows  are 
placed  behind  the  forge,  with  a  pipe, 
and  are  worked  by  means  of  a  lever, 
called  a  rocket.  Steam  machinery 
is  now  much  used  in  the  generating 
of  wind  for  blowing  the  wind  or 
furnace 

Bellow9t  or  water-blowing  engine,  is  a 
machine  in  which  the  stream  of  air 
is  supplied  by  the  flowing  of  water 

Belly,  the  hollow  part  of  a  compass 
timber,  the  round  part  of  whidi  is 
called  the  back 

Belt,  in  building,  a  string-course  and 
blocking-course ;  a  course  of  stones 
projecting  from  awall,  either  mould- 
ed, plain,  fluted,  or  enriched 

Behedere,  a  turret,  lantern,  or  cupola, 
raised  above  the  roof  of  a  building. 
It  is  sometimes  applied  in  Italy  to 
open  galleries  or  corridors 

Bema,  an  ambo,  or  reading-desk;  a 
raised  structure  forthe  seator throne 
of  a  bishop 

Bema,  the  sanctuary,  presbytery;  or 
chancel  of  a  church 

Bema,  in  Greek,  the  platform  from 
which  the  orators  spoke  in  the 
Athenaeum 

Ben^Hve,  Cornish  mining 

Bench,  for  carpenters  and  joiners  to 
do  their  work  on,  usually  10  or  12 
feet  in  length,  and  about  2^  feet  in 
width 

Benehplanee,  The  jack-plane,  the  try. 
ing'plane,  the  long-plane,  the  jointer, 
and  the  smoothing-plane,  are  called 
bench  planes 

Bench  idle,  a  low  stone  seat  round 
the  interior  of  the  walls  of  many 
churches 

Bend,  in  mining,  indurated  clay,  a 
name  given  by  miners  to  any  indu- 
rated argillaceous  substance 

Bend,  the  form  of  the  ship  from  the 
keel  to  the  top  of  the  side,  as  the 
midship  bend,  &c. 

ii  ~~ 


Bend,  in  heraldry,  an  honourable  dr' 
dinary,  formed  by  lines  drawn  fron^ 
the  dexter-comer  to  the  sinister- 
base  J 

Bends,  the  strongest  part  of  a  vessdi 
side,  to  which  the  beams,  knees,  aoa 
foot-hooks  are  bolted 

Bending  •  strakee,  are  two  strakei 
wrought  near  the  coverings,  worked 
an  fore  and  aft,  about  one  inch  oi 
one  inch  and  a  half  thicker  than 
the  rest  of  the  deck,  and  let  doivn 
between  the  beams  and  ledges  so  u 
the  upper  side  to  be  even  with  the 
rest  of  the  deck 

Bending  of  timber.  The  process  of 
bencUng  wood  to  any  required  curve 
depends  on  the  property  of  heat,  for 
its  pressure  increases  the  elasticity 
of  the  wood 

Bendlet,  in  heraldry,  the  sixth  part  of 
a  shield 

Bendy,  in  heraldry,  applied  to  the 
field  when  divided  into  parts  dia- 
gonally, and  varying  in  metal  and 
colour 

Benefice,  a  church  endowed  with  are- 
venue  for  the  performance  of  divine 
service 

Benetier,  a  vessel  to  containholy  water; 
a  font,  or  piscina 

Ben-heyl,  in  Cornish  mining,  rich  in  tin 

Benttekshroude,  formerly  used,  and 
extending  from  the  futtock  staves 
to  the  opposite  channels 

Benzine,  the  bi-carburet  of  hydrogen, 
procured  by  heating  benzoic  add 
with  lime 

Bergmote,  a  court  held  on  a  hiU  tp 
decide  controversies  among  nu- 
ners 

Berne  machine,  for  rooting  up  trees, 
the  invention  of  Peter  Sommer,  ol 
Berne 

Berth,  the  place  where  a  vessel  nes; 
the  place  in  which  a  man  sleeps 

Beryl,  a  pellndd  gum,  of  a  bluish  green 
colour,  found  in  the  East  Indies, 
Peru,  &c.,  used  by  artists 

Betty,  in  mechanics,  an  instrument  to 
break  open  doors 

Bevel,  any  angle  except  one  of  90  de- 
grees 

Bevel,  in  bricklaying,  is  for  drawinj 


BEV 


BILLET  MOULDING. 


BIN 


the  soffit-line  on  the  ttuce  of  the 
bricks 
Bevel,  in  jdmesry.  One  side  is  said  to  be 
beyelled  with  respect  to  another, 
when  the  angle  formed  by  these  two 
sides  is  grei^er  or  less  than  a  right 
angle 
Bevel  ffear^  in  mechanics,  denotes  a 
species  of  wheel-work  where  the 
axis  or  shaft  of  the  leader  or  driver 
forms  an  angle  with  the  axis  or  shaft 
of  the  follower  or  the  driven.  In 
practice  it  ia  requisite  to  have  finite 
and  sensible  teeth  in  bevel  gear: 
these  are  made  similarly  to  those  of 
spur  gear,  except  that  in  the  latter 
they  are  parallel,  while  in  bevel  gear 
they  HimJTiiiih  in  length  and  tluck- 
ness  in  approaching  the  apex  of  the 
cone :  the  teeth  are  of  any  breadth, 
according  to  the  strength  required. 
Bevel  gearing  ia  stronger,  works 
smoother,  and  has  superseded  the 
fiu)e-wheel  and  tnmdle 

BevtOmfff  in  ship-bmlding,  the  wind- 
ing of  a  timber,  &c,  agreeably  to 
directions  given  fmm  the  mould-loft 

Betel-wheel,  a  wheel  having  teeth 
ftnrmed  so  as  to  woric  at  an  angle 
either  greater  or  less  than  half  a 
right  angple 

Bibia,  in  ship-bnilding,  pieces  of  tim- 
ber bolted  to  the  hounds  of  a  mast, 
to  sapport  the  trestle-trees 

BibUotkeea,  in  Greek,  the  place,  apart- 
ment or  bmldiiig  where  books  were 
hept 

Bicarbide  qf  hydrogen.  This  gas  is 
knovm  by  tiie  names  of  light  csr- 

i  buretted  hydrogen,  marsh-gas,  fire- 
damp, and  gas  of  the  acetates.  It 
ia  discharged  from  fissures  in  coal 
in  large  quantities,  snd  from  the 
bottoms  of  the  pools  in  which  there 
is  vegetable  matter 

Biee,  a  blue  ooloi^r  used  in  painting, 
prepared  from  the  lapis  Armenius 

Bice  or  Bue,  in  painting,  a  pale  blue 
colour,  procured  by  the  reduction 
of  smalt  to  a  fine  powder 

Bieelham,  the  dweUing  of  a  tradesman, 
havii^  under  it  two  vaults,  for  the 
reception  of  merchandise 

BteAoM,  a  turret  or  watch-tower 


Bier-balkf  the  church  road  for  burials 

Bifirtme,  in  sculpture,  double-fronted 
or  freed,  usually  applied  to  Janus 

Bigeff  an  arch  or  chamber 

Bigg,  to  build 

Bigger,  a  builder 

Bighi,  the  double  part  of  a  rope  when 
it  is  folded,  in  contradistinction 
from  the  ends 

Bikmder,  a  smaU  vessel  with  two 
masts,  used  chiefly  in  the  canals  of 
the  Low  Countries 

BUboea,  large  bars  or  bolts  of  iron, 
with  sluu^les  sliding  on  them,  used 
for  criminals 

Bileetion^mouldmg9,thosesurroxmi&ng 
the  panels,  and  projecting  before 
the  face  of  a  door,  gate,  &c. 

Bilge,  that  part  of  the  floor  of  a  ship 
wMoh  approaches  nearer  to  an  hori- 
zontal than  to  a  perpendicular  di- 
rection 

BUge'-pwmp,  the  forcing-pump  worked 
by  a  marine  engine,  to  discharge 
the  bilge-water  from  the  vessel 

Bi^e-fmmp  rod,  the  plunger'^rod,  or 
rod  connecting  the  piston  of  the 
bilge-pump  to  one  of  the  side-levers 

Bill,  the  point  at  the  extremity  of  the 
fluke  of  an  anchor 

BUlet-fnouldmg,  an  ornament  used  in 
sMng-Gourses  and  the  archivolts  of 
windovfs  and  doors 

BHUon,  in  numbers,  the  sum  of  a  mil- 
lion of  millions 

Bills,  the  ends  of  compass  or  knee- 
timber 

Bimedial  Hue,  in  geometry,  the  sum 
of  two  mectiaU.  When  medial  lines, 
equal  only  in  power  and  containing 
a  rational  rectangle,  are  compound- 
ed, the  whole  vrill  be  irrational 
with  respect  to  either  of  the  two : 
this  is  called  a  first  bimedial  line ; 
but  if  two  medial  lines,  commen- 
surable only  in  power,  and  con- 
taining a  medial  rectangle,  be  oom- 
poun£d,  the  whole  will  be  irra- 
tional, and  is  then  called  a  second 
bimedial  line 

Binary,  in  arithmetic,  double 

Binder,  one  who  undertakes  to  keep 
a  mine  open 

Binding-joiata,  those  beams  in  a  floor 


49 


BIN 


BITUMEN. 


BIT 


1 


which  support  transvenely  the 
bridgingB  above  and  the  oeUing- 
joistB  below 

BindingSf  the  iron  wrought  round  the 
dead-eyes 

Binnaclet  a  box  near  the  hehn,  con- 
taining the  compass 

Binocular  telescope t  one  to  which  both 
eyes  may  be  applied 

BinSf  for  wine,  open  snbdiyisions  in  a 
cellar  for  the  reception  of  bottles 

Birch  woodi  a  forest  tree  common  to 
Europe  and  North  America;  an 
excellent  wood  for  turning,  being 
of  light  colour,  compact,  and  easily 
worked 

Birds,  in  heraldry,  are  emblems  of 
expedition,  liberty,  &c. 

Bird's-eye  perspective  is  of  two  kinds, 
angular  and  parallel :  it  is  used  in 
the  drawings  of  extensive  bmldings 
having  spacious  courts  and  gardens, 
as  palaces,  colleges,  asylums,  &c 
The  observer  is  supposed  to  be  on 
an  eminence,  and  looking  down  on 
the  building,  as  from  a  steeple  or 
mountain 

Bird'S'tnouthf  in  carpentry,  an  interior 
angle  or  notch  cut  in  the  end  of  a 
piece  of  timber  for  its  reception  on 
the  edge  of  a  pole  or  plate.  It  sig- 
nifies also  the  internal  angle  of  a 
polygon 

Bireme,  a  vessel  with  two  banks  or 
tiers  of  oars 

Birhombaidal,  having  a  8ur£ace  of 
twelve  rhombic  faces,  which,  being 
taken  six  and  six,  and  prolonged 
till  they  intercept  each  other,  would 
form  two  different  rhombs 

Birthing,  the  working  a  top  side,  bulk- 
heads,  &c. 

Bisection,  in  geometry,  the  division  of 
any  quantity  into  two  equal  parts 

Bishops,  prelates  holding  baronies  of 
the  King  or  of  the  Pope,  and  exer- 
cising  ecclesiastical  jurisdiction  over 
a  certain  extent  of  territory,  called 
their  diocese 

Bismuth.  This  metal  is  found  native, 
crystallized  in  cakes,  which  gene- 
rally contain  small  quantities  of 
silver;  it  is  also  combined  with 
oxygen,  arsenic,  and  sulphur 


Bispia,  a  bishopric  or  episcopal  pa- 
lace 

Bissextik,  or  leap-year,  a  year  con- 
sisting of  366  days,  happening  once 
every  four  years,  by  the  addition  of 
a  day  in  the  month  of  February,  to 
recover  the  six  hours  which  the 
sun  spends  in  his  course  each  year, 
beyond  the  365  days  usually  aUow- 
edforit 

Bistre,  a  brown  pigment,  extracted 
by  watery  solution  from  the  soot 
of  wood  fires,  when  it  retains  a 
strong  pyroligneons  scent.  It  ii 
of  a  wax-like  texture,  and  tff  a  ci- 
trine-brown colour,  perfectly  dura* 
ble.  It  has  been  much  used  as  a 
water  colour,  particularly  by  the 
old  masters,  in  tinting  drawings 
and  shading  sketches,  previously  to 
Indian  ink  coming  into  general  use  | 
for  such  purposes.  In  oil,  it  dries 
with  the  greatest  difficulty 

Bisturres,  small  towers  placed  at  in- 

•  tervals  in  the  walk  of  a  fortress, 
forming  a  barbican 

Bit,  an  instroment  for  boring  holes  in 
wood,  &c 

Bitter  end,  that  part  of  the  cable 
which  is  abaft  the  bitts 

Bitter  Nut  wood,  a  native  of  America, 
is  a  large  timber  wood,  measuring 
30  inches  when  squared ;  plain  and 
soft  in  the  grain,  like  walnut 

Bats,  in  ship-building,  perpendicular 
pieces  of  timber  going  through  the 
deck,  placed  to  secure  any  thing  to. 
The  cables  are  fastened  to  them,  if 
there  is  no  windlass.  There  are 
also  bitts  to  secure  the  windlass, 
and  each  side  of  the  heel  of  the 
bowsprit 

Bitumen,  a  name  for  a  number  of 
inflammable  mineral  substances, 
known  under  the  names'  of  naph- 
tha, mineral  tar,  mineral  pitch, 
sea-wax,  asphalte,  elastic  bitumen, 
or  mineral  caoutchouc,  jet,  mineral 
coal,  &c. 

Bituminous  eemeni,  a  factitious  sub- 
stance, used  for  pavements,  for 
roofs,  and  other  uscdfiil  purposes 

Bituminous  ttmestone,  a  limestone  of 
a  lamellar  stnicture 


BLA. 


BLAST-PIPE. 


BLE 


Biack,  the  last  and  the  lowest  in  the 
series  or  scale  of  descending  co- 
lours; the  opposite  extreme  finom 
white;    the  maximum  of  colour. 
To  be  perfect,  it  must  be  neutral 
with  respect  to  colours  individually, 
and  absolutely  transparent,  or  desti- 
tute of  reflective  power  in  regard 
'     to  hght ;  its  use  in  painting  being 
j     to  represent  shade  or  depth,   of 
which  it  is  the  element  in  a  picture 
and  in  colours,  as  white  is  of  light 
Blaei-band  ironstone,  discovered  by 
Mr.  David  Mushet,  in  1801,  ^hile 
engaged  in    the   erection  of  the 
Calder  iron  works.   Great  prejudice 
was  exerted  against  him  by  the 
iron-masters,  in  presuming  to  class 
the  wild  coals  of  the  country  with 
iron-stones  fit  and  proper  for  the 
blast  furnace;  yet  that  discovery 
has  ^evated  Scotland  to  a  consi- 
derable  rank  amongst  the  iron- 
making  nations  of  Europe,  and  pro- 
duces an  annual  average  income  of 
£16,500    to    Sir    W.  Alexander, 
Bart. 
Black  Botany  Bay  wood  is  the  hardest 
and  most  wasteful  of  all  woods: 
some  of  the  finest,  however,  if  well 
selected,  exceeds  all  woods  for  ec- 
centric turning 
Black  chalk  is  an  indurated  black 
I     clay,  of  the  texture  of  white  chalk: 
I     its  principal  use  is  for  cutting  into 
the  crayons  which  are  employed  in 
sketching  and  drawing 
Black  dye.   The  ingredients  of  black 
I     dye  are  logpnrood,  Aleppo  gaUs,  ver- 
{     digris,  and  sulphate  of  iron,  or  green 

vitriol 
t  Black  tron,  malleable  iron,  in  contra- 
distinction to  that  which  is  tinned, 
called  white  iron 
Black  Jack,  in  mining,  blende 
Black  lead,  plumbago,  or  graphite,  is 
a  naUve  carburet  of  iron,  or  oxide 
of  carbon,  found  principally  at  Bor- 
rodale  in  Cumberland;  consumed  in 
large  quantities  in  the  formation  of 
crayons  and  black-lead  pencils  for 
writing,  sketching,  designing,  and 
drawing 
Black  octare^  a  yaxiety  of  the  mine- 


ral black,  combined  with  iron  and 
alluvial  clay 

Black  tin,  tin  ore  when  drened, 
stamped,  and  vrashed,  ready  far 
melting 

Black  wadd,  one  of  the  ores  of  man- 
ganese, used  as  a  drying  ingredient 
in  paints 

Blade,  in  joinery,  is  expressive  of  any 
part  of  a  tool  that  is  broad  and 
thin,  as  the  blade  of  an  axe,  of  an 
adze,  of  a  chisel,  of  a  square :  the 
blade  of  a  saw  is  more  frequently 
called  the  plate 

Blades,  the  principal  lafiers  or  bnaks 
of  a  roof 

Blanc  d^argent,  or  silver  white.  This 
is  a  false  appellation  ^or  a  white 
lead,  called  also  Frtoch  white.  It 
is  first  produced  .in  the  form  of 
drops,  is  exquisitely  white,  but  is 
of  less  body  than  flake  white,  and 
has  all  the  properties  of  the  best 
white  leads;  but,  being  liable  to 
the  same  changes,  is  imfit  for  gene- 
ral use  as  a  water  colour,  though 
good  in  oil  or  varnish 

B^tt  the  air  introduced  into  a  fur- 
nace 

Blasting  of  stone,  from  rocks  and 
beds  -of  stone,  for  the  purpose  of 
quarrying  and  shaping  stones  to  be 
used  for  building  purposes.  The 
ordinary  implements  used  are  the 
jumper  or  cutting-tool,  the  ham- 
mer, and  scraper.  For  the  process 
and  its  effect,  see  Sir  John  Bur- 
goyne's  Rudimentary  Volume  on 
Blasting,  &c 

Blast-p^e,  the  waste  steam-pipe  of 
an  engine,  but  more  particularly 
applied  to  locomotive  engines :  in 
the  latter  it  leads  from  the  exhaust 
passages  of  the  cylinders  into  the 
chimney,  and  is  of  great  use  for 
forming  the  draught  through  the 
flre-tul£ss,  as  eadi  jet  of  steam 
emitted  creates  a  partial  vacuum  in 
the  chimney,  which  is  immediately 
filled  by  a  cmrent  of  air  rushing 
through  the  fire-grate 

Blazonry,  in  heraldry,  deciphering  of 
coats  of  arms 

Bleac1ung,Ka.  art  divided intobranches. 


51 


BLE 


BLOW-OFF  PIPE. 


BL.O 


bleaching  of  yegetable  and  animal 
substances  requiring  different  pro- 
cesses for  whitening  them 

Blende,  in  mining,  one  of  the  ores  of 
zinc,  composed  of  iron,  zinc,  sul- 
phur, silex,  and  water:  on  being 
scratched,  it  emits  aphosphoriclight 

Blending  and  melting,  in  colouring 
or  painting,  are  synonymous  terms. 
They  imply  the  method  of  laying 
different  tints  on  buildings,  trees, 
&c.,  so  that  they  may  mingle  to- 
gether while  wet,  and  render  it  im- 
possible to  discover  where  one 
colour  begins  and  another  ends. 
A  variety  of  tints  of  neariy  the 
same  tone,  employed  on  the  same 
object  and  on  the  same  part,  gives 
a  richness  lind  mellowness  to  the 
effect ;  while  the  outline,  insensibly 
melting  into  the  back-ground,  and 
artfuUy  disappearing,  binds  the  ob- 
jects together,  and  preserves  them 
in  unison 

Bleostanrnfff  Mosaic  pavement 

Bloekf  a  lump  of  wood  or  stone 

Blocks,  pieces  of  wood  in  which  the 
sheaves  or  pulleys  run,  and  through 
which  the  ropes  pass 

Block  cornices  and  entablatures  are 
frequently  used  to  finish  plain  build- 
ings, where  none  of  the  regular  or- 
ders have  been  employed.  Of  this 
kind  there  is  a  very  beautiful  one 
composed  by  Vignola,  much  used 
in  Italy,  and  employed  by  Sir  Chris- 
topher Wren  to  finish  the  second 
design  of  St.  Paul's  cathedral 

Block-house,  a  building  erected  by  be- 
siegers for  the  investment  of  a  cas- 
tle. Block-houses  were  erected  in 
the  time  of  Henry  YIIl.  on  the 
south  and  south-western  coast  of 
England 

Blocking-course,  a  course  of  masonry 
or  brick-work,  laid  on  the  top  of  a 
cornice  crowning  a  wall 

Blockings,  small  pieces  of  wood,  fitted 
in,  or  glued,  or  fixed  to  the  interior 
angle  of  two  boards  or  other  pieces, 
in  order  to  give  strength  to  the 
joint 

Block-machinery,  the  machinery  for 
manufacturing  ships'  blocks,  invent- 

52 


ed  by  the  elder  Brunei,  and  ad- 
justed by  the  late  Dr.  Gregmry 

Block-tin,  tin  cast  into  blocks  or  in- 
gots 

Blood-red  heat,  the  degree  of  heat 
which  is  only  necessary  to  reduce 
the  protuberances  on  coarse  iron  by 
the  hammer,  in  order  to  prepare  it 
for  the  file,  the  iron  being  previ- 
ously brought  to  its  shape.  This 
heat  is  also  used  in  punddng  small 
pieces  of  iron 

Bloom,  a  mass  of  iron  after  having  un- 
dergone the  first  hammering 

Blower,  in  mining,  a  smelter 

Blowing,  the  projection  of  air  into  a 
furnace,  in  a  strong  and  rapid  cur- 
rent, for  the  purpose  of  increasing 
combustion 

Bk/w-off  cock,  the  stop-cock  in  the 
blow-off  pipe 

Blow-off  p^,  the  pipe  fixed  to  the 
bottom  ol  a  boiler,  for  discharging 
the  sediment,  whidi  is  efifected  by 
blowing  through  a  portion  of  the 
water  from  the  boiler 

Blow-p^.  The  blow-pipe  is  a  most 
valuable  little  instrument  to  the 
mineralogist,  as  its  efi^ects  are  strik- 
ing, rapid,  well  characterized,  and 
pass  immediately  under  the  eye  of 
the  operator.  Tlie  most  eflScadous 
fiame  is  produced  by  a  reg^idar,  mo- 
derate stream  of  air ;  wMe  the  act 
of  blowing  with  more  force  only 
has  the  effect  of  fatiguing  the  mus- 
cles of  the  cheeks,  oppressing  the 
chest,  and  at  the  same  time  renders 
the  flame  imsteady. 

The  student  should  fill  his  mouth 
with  air,  so  as  to  inflate  the  cheeks 
moderately,  and  continue  to  breathe 
without  letting  the  air  in  the  mouth 
escape ;  the  blow-pipe  may  then  be 
introduced  between  the  lips,  and 
while  the  breathing  is  carried  on 
through  the  medium  of  the  nose, 
the  <£eeks  will  expel  a  stream  of 
air  through  the  blow-pipe ;  and  by 
replenishuig  the  mouth  at  each  ex- 
piration, and  merdy  discharging 
the  surpbu  air  through  the  nosbils, 
a  facility  will  be  acquired  of  keep- 
ing up  a  constant  stream  of  air. 


BLO 


BLOW.PIPE. 


BLU 


The  best  flame  for  the  purpose 
of  this  instrument  is  that  of  a  thick 
wax  candle,  such  as  are  made  for 
the  lamps  of  carriages,  the  wick 
being  snuflfed  to  sudi  a  length  as 
to  occasion  a  strong  combustion: 
it  should  be  deflected  a  little  to  one 
sidC)  and  the  current  of  air  directed 
along  its  smface  towards  the  point : 
a  well-defined  cone  will  be  pro- 
duced, consisting  of  an  external 
yellow,  and  an  internal  blue  flame. 
At  the  point  of  the  former,  calcina- 
tion, the  oxidation  of  metals,  roast- 
ing of  ores  to  expel  the  sulphur 
and  other  volatile  ingredients,  may 
be  accomplished;  and  by  the  ex- 
treme point  of  the  latter  (which 
aflbrds  the  most  intense  heat)  fa- 
sion,  the  deoxidation  of  metals,  and 
all  those  operations  which  require 
the  highest  temperature,  will  be 
efflected.    The  piece  of  mineral  to 
be  examined  must  necessarily  be 
supported  on  some  substance ;  and 
for  the  earths,  or  any  subject  not 
being  metallic,    or  requiring  the 
opention  of  a  flux,  a  spoon  or  pair 
of  forceps  made  of  platina  will  be 
found  useful;  but,  as  the  metals 
and  most  of  the  fluxes  act  on  pla- 
tina, the  most  serviceable  support, 
for  general  purposes,  will  be  a  piece 
of  sound,  well-bumt  charcoal,  with 
the  baric  scraped  off,  as  free  as  pos- 
sible finom  knots  or  cracks:  the 
piece  of  mineral  to  be  examined 
should  not  in  general  be  larger  than 
a  pepper-corn,  which    should  be 
plaiced  in  a  hollow  made  in  the 
charcoal;  and  the  first  impression 
of  the  heat  should  be  yery  gentle, 
as  the  sudden  application  of  a  high 
temperature  is  extremely  liable  to 
destroy  those  efltects  which  it  is 
most  material  to  observe.    Many 
substances  decrepitate  immediately 
they  become  hot;  and  when  that  is 
found  to  be  the  case,  they  should 
be  heated  red,  under  circumstances 
whidi  will  prevent  their  escape: 
this   may  be   effected,  with  the 
earthy  minerals,  by  wrapping  them 
m  a  piece  of  platina  foU,  and,  with 


the  metallic  ores,  by  confining  them 
between  two  pieces  of  charcoal, 
driving  the  point  of  the  flame 
through  a  small  grooye  towards  the 
place  where  the  mineral  is  fixed,  by 
which  means  a  sort  of  reverberating 
furnace  may  be  formed.  The  prin- 
cipal phenomena  to  be  noticed  are, 
phosphorescence,  ebullition,  intu- 
mescence, the  exhalation  of  vapours 
having  the  odour  either  of  sulphur 
or  garlic  (the  latter  arising  from 
the  presence  of  arsenic),  decrepita- 
tion, fusibility;  and,  amongst  the 
fusible  minerals,  whether  the  pro- 
duce is  a  transparent  glass,  an 
opaque  enamel,  or  a  bead  of  metal. 
Having  first  made  some  observa- 
tions on  a  particle  of  the  mineral 
alone,  either  the  residue  or  a  fresh 
piece  should  be  examined  with  the 
addition  of  a  flux,  more  particularly 
in  the  case  of  the  ores,  as  the  na- 
ture of  the  metal  may  be  generally 
decided  by  the  colour  with  which 
it  tinges  the  substance  used.  The 
most  eligible  flux  is  glass  of  borax: 
a  piece  about  half  the  size  of  a  pea 
bdng  placed  on  the  charcoal,  is  to 
be  heated  till  it  melts ;  the  particle 
of  ore  being  then  taken  in  a  pair  of 
forceps,  is  to  be  pressed  down  in  it, 
and  the  heat  applied;  or,  should 
the  mineral  not  be  inclined  to  de- 
crepitate, it  may  be  laid  on  the 
chfuxjoal,  and  two  or  three  pieces 
of  glass  of  borax,  about  the  size  of 
a  pin's  head,  placed  over  it ;  and  on 
using  the  blow-pipe,  the  whole  vnll 
form  itself  into  a  globular  bead. 

Blow-vahe,  the  *  snifting  valve  *  of  a 
condensing  engine 

Bhef  one  of  the  seven  primitive  co- 
lours of  the  rays  of  light,  into  which 
they  are  divided  when  refracted 
through  a  glass  prism 

Bhte-blaek  is  a  well-bumt  and  lavi- 
gated  charcoal,  of  a  cool,  neutral 
colour,  and  not  differing  frt)m  the 
common  Frankfort  black.  Blue- 
black  was  formerly  much  employed 
in  painting,  &c. 

Bhte  carmine  is  a  blue  oxide  of  mo- 
lybdena,  of  which  little  is  known 


BLU 


BOATS. 


BOB 


as  a  substance  or  as  a  pigment. 
It  is  said  to  be  of  a  beautiful  blue 
colour,  and  durable  in  a  strong 
light,  but  is  subject  to  be  changed 
in  hue  by  other  substances,  and 
blackened  by  foul  air:  we  may 
conjecture,  therefore,  that  it  is  not 
of  much  value  in  painting 

Blue  dyett  indigo,  Prussian  blue,  log- 
wood, bilberry,  &c. 

Bhteinfft  the  process  of  heating  iron, 
and  some  other  metals,  until  they 
assume  a  blue  colour 

BhteJohn,  fluor  spar,  called  so  by 
Derbyshire  miners 

Blue  ochre  is  a  mineral  colour  of  rare 
occurrence,  found  with  iron  pyrites 
in  Cornwall,  and  also  in  North 
America,  and  is  a  subphosphate  of 
iron.  What  Indian  red  is  to  the 
colour  red,  and  the  Oxford  ochre 
to  yellow,  this  is  to  other  blue  co- 
lours. They  dass  in  likeness  of 
character:  hence  it  is  admirable 
rather  for  the  modesty  and  soUdity, 
than  for  the  brilliancy  of  its  colour 

Blue  pigments,  found  in  common,  are 
Prussian  blue,  mountain  blue,  Bre- 
men blue,  iron  blue,  cobalt  blue, 
smalt,,  charcoal  blue,  ultramarine, 
indigo,  litmus,  and  blue  cake 

Blue  tint,  in  colouring,  is  made  of 
ultramarine  and  white,  mixed  to  a 
lightish  azure.  It  is  a  pleasant 
working  colour,  and  with  it  shoidd 
be  blended  the  gradations  in  a  pic- 
ture. It  follows  the  yellows,  and 
with  them  it.  makes  the  greens; 
and  with  the  red  it  produces  the 
purples.  No  colour  is  so  proper 
for  blending  down  or  softening  the 
lights  into  keeping.  In  pictures  of 
less  yalue,  Antwerp  blue- may  be 
substituted  for  ultramarine 

Blue  verditer  is  a  blue  oxide  of  cop. 
per,  or  precipitate  of  the  nitrate  of 
copper  by  lime,  and  is  of  a  beauti- 
fill  light-blue  colour.  It  is  little 
affected  by  light ;  but  time,  damp, 
and  impure  air  turn  it  green,  and 
ultimately  blacken  it,  —  changes 
which  ensue  even  more  rapidly  in 
oil  than  in  water :  it  is,  therefore, 
by  no  means  an  eligible  pigment  in 


oil,  and  is  principally  confined  to 
distemper,  painting,  and  the  uses 
of  the  paper-stainer,  though  it  has 
been  found  to  stand  well,  many 
years,  in  water-colour  drawings  and 
in  crayon  paintings,  when  preserved 
dry. 

Blue  vitriol,  sulphate  of  copper 

Bhtf :  a  bluff-bowed  or  bluff-headed 
vessel  is  one  which  is  full  and 
square  forward 

Bhtnk,  heavy  cotton  doth :  the  term 
used  in  Scotland 

Board,  a  substance  of  wood  contained 
between  two  parallel  planes;  as 
when  the  banlk  is  divided  into  se- 
veral pieces  by  the  pit-saw,  the 
pieces  are  called  boards 

Board,  in  nautical  language,  the  line 
over  which  a  ship  runs  between 
tack  and  tack.  To  board  is  to  en- 
ter a  ship 

Boarding -floorf  are  those  covered 
with  boards :  the  operation  of 
boarding  floors  should  conomence 
as  soon  as  the  windows  are  in,  and 
the  plaster  dry 

Boarding-joists,  joists  in  naked  floor- 
ing, to  which  the  boards  are  fixed 

Boarding-pike,  a  pike  used  by  sailors 
in  boarding  an  enemy's  vessel 

Boasting,  in  masonry,  the  paring  of  a 
stone  with  a  broad  chisel  and  mal- 
let 

Boasting,  in  sculpture  or  earving,  is 
the  rough  cutting  of  a  stone  to  form 
the  outline  of  a  statue  or  ornament 

Boats,  small  open  vessels,  impelled  on 
the  water  by  rowing  or  sailing, 
having  different  uses,  dimensions, 
&c.,  either  for  river  or  sea  service 

Boat-hook,  an  iron  hook  with  a  sharp 
point,  fixed  on  a  pole,  at  the  extre- 
mity 

Boatswain,  a  warrant  ofllcer  in  the 
navy,  who  has  the  charge  of  the 
rigging,  and  calls  the  crew  to  duty 

Bob,  the  miner's  engine-beam 

Bob,  of  a  pendulum,  is  the  metallic 
weight  which  is  attached  to  the 
lower  extremity  of  a  pendulum  rod 

Bobstay-holes,  those  in  the  fore-part 
of  the  knee  of  the  head,  for  the  se- 
curity of  the  bobstay 


BOB 


BOILERS. 


BO 


Bob-stays^  used  to  confine  the  bow- 
sprit down  to  the  stem  or  the  cut- 
water 

Boeafornan,  anciently  a  daughter- 
house 

BodtuMt  ft  crypty  or  sabtemmeous 
chapel 

Bodyt  in  physics  or  natural  philosophy, 
any  solid  or  extended  palpable  sub- 
stauoe 

Bodiff  or  solid,  in  geometxy,  has  three 
dimensions;  length,  breadth,  and 
thickness.  Bodies  are  either  hard, 
soft,  or  elastic 

BodyplaHf  in  naval  architectural  draw- 
ing, sectional  parts  showing  fore  and 
after  parts  of  a  vessel 

Boerutf  anciently  a  niaaor-honse  or 
large  country  dwelling 

Bofff  soft,  marshy,  and  spongy  matter, 
or  quagmire.  RailrcMbds  haye  been 
made  across  bogs  in  Lancashire  and 
in  America  by  draining,  &c.,  and  in 
the  bitter  by  piling  as  well  as  drain- 
ing 

Bog4ron  ore,  an  iron  ore  disooYerable 
in  boggy  land 

BoUetf  a  wroi^ht  iron  vessel  contain- 
ing water,  to  whicdi  heat  is  applied 
for  the  generation  of  steam.  Boilers 
are  made  of  various  forms,  according 
to  the  nature  of  their  application, 
and  are  constructed  so  as  to  obtain 
the  hugest  heating  suiftce  with  the 
least  cubical  content 

Boikn.  A  boiler  for  20-hor8e  power  is 
usually  15  feet  long  and  6  feet  wide; 
therefore  90  feetof  sur&ce,  or4ifeet 
to  1  horse  power;  a  boiler  for  a 
l4.horse  }M>wer  60  feet  of  surface, 
or  4*3  feet  to  1  horse  power ;  but 
engineers  allow  5  feet  of  surface  to 
1  horse  power,  and  Mr.  Hicks,  of 
Bolton,  proportions  his  boilers  at 
the  rate  of  5^  square  feet  of  hori- 
zontal sur&ce  of  water  to  each  horse 
power:  Mr.  Watt  allows  25  cubic 
feet  of  space  to  each  horse  power 

BoUen.  Iron  cement  is  far  preferable 
to  any  other  material  for  making 
iron  joints:  it  has  the  excellent 
property,  that  it  becomes  more 
sound  and  tight  the  longer  it  stands, 
so  that  cemented  joints  which  at 

""~55 


first  may  be  a  little  leaky,  soon  be 
come  perfectly  tight.  The  follow 
ing  is  the  best  mode  of  preparing 
this  iron  cement :  take  16  parts  o 
iron  filings,  free  from  rust ;  3  parti 
powdered  sal-ammoniac  [muriati 
of  ammonia] ;  and  2  parts  of  flowei 
of  sulphur :  mix  all  together  inti. 
mately,  and  preserve  the  compounc 
in  a  stoppered  vessel,  kept  in  a  drj 
place,  until  it  is  wanted  for  use 
Then  take  1  part  of  the  mixture, 
add  it  to  12  parts  of  clean  iron 
filings,  and  mix  this  new  compound 
with  so  much  water  aa  will  bring  i1 
to  the  consistence  of  a  paste,  hav- 
ing previously  added  to  the  water 
a  few  drops  of  sulphuric  acid.  In- 
stead oi  filii^  of  hanmiered  iron, 
filings,  turnings,  or  borings  of  cast 
iron  may  be  used ;  but  it  must  be 
remarked,  that  a  cement  made  en- 
tirely of  cast  iron  is  not  so  tena- 
cious and  firm  as  if  of  wrought 
iron;  it  sooner  crumbles  and  breaks 
away.  It  is  better  to  add  a  certain 
quantity,  at  least  one-third,  of  the 
latter  to  the  former. 

There  is  but  little  ground  to  fear 
for  the  soundness  of  a  well-riveted 
iron  boiler;  for  in  time  the  action 
of  rust  and  deposit  will  stop  almost 
any  crevices.  In  order,  however,  to 
take  all  precaution,  it  is  to  be  re- 
commended that  some  clammy 
substance,  such  as  horse-dung,  bran, 
coarse  meal,  or  potatoes,  should  be 
boiled  in  the  vessel  before  it  is  used. 
A  very  small  quantity  also  of  the 
same  kind  of  substance  may  be  put 
into  the  boiler  when  first  set  to  work : 
this  vrill  find  its  way  into  the  cre- 
vices by  the  pressure  within,  and, 
gradually  hardening,  will  soon  ren- 
der the  vessel  perfectly  sound. 
Boilers.  Copper  is  more  tough  and 
less  liable  to  crack  than  iron,  and 
is  a  most  excellent  material  for 
high-pressure  boilers :  it  has,  how- 
ever, a  less  cohesive  power;  and 
therefore  a  greater  thickness  of  me- 
tal is  necessary  to  produce  an  equal 
strength :  but  since  copper  boilers 
never  fly  in  pieces  in  case  of  explo- 


BOI 


BOND  TIMBER. 


BON 


rion,  it  is  not  necessary  to  be  too 
scrupulous  in  regard  to  this  point. 
Even  when  the  metal  is  thin,  espe- 
cially if  the  diameter  is  not  great, 
the  use  of  copper  removes  all  dan- 
ger of  destructive  explosion,  since 
at  most  only  a  simple  tearing  asun- 
der of  the  metal  Will  ensue 
BoUmfft  or  ebullition,  the  agitation  of 
fluids,  arising  from  the  action  of 
fire,  &c. 
Bole,  an  argillaceous  mineral,  having 
a  conchoidal  fracture,  an  internal 
lustre,  and  a  shining  streak 
Bottarda,  large  posts  set  in  the  ground 
at  eadi  side  of  the  docks,  to  lash 
and  secure  hawsers  for  docking  and 
undocking  ships 
BoUard  tifnbera,  in  a  ship,  two  timbers 
within  the  stem,  one  on  each  side 
of   the   bowsprit,   to   secure   its 
end 
Bolognes  School^  in  painting,  a  Lom- 
bard school,  founded  by  Caracd 
Bolognian  stone  is  derived  from  sul- 
phate of  baryta  by  calcination  and 
sure  to  the  rays  of  the  sun 
Bolster,  a  piece  of  timber  placed  upon 
the  upper  or  lower  cheek,  worked 
up  about  half  the  depth  of  the 
hawse-holes,  and  cut  away  for  the 
easement  of  the  cable,  and  to  pre- 
vent its  rubbing  the  cheek;  hke- 
vnse  the  solid  piece  of  timber  that 
is  bolted  to  the  ship's  side,  on  which 
the  stantients  for  the  linings  of  the 
anchors  are  placed;   or  any  other 
small  piece  fixed  under  the  gunwale, 
to  prevent  the  main  sheet  from  being 
rubbed,  &c. 
Bolster,  a  tool  used  for  punching  holes 

and  for  making  bolts 
Bolster  qfa  capitals  the  flank  of  the 

Ionic  capital 
Bolt,  a  cylindrical  pin  of  iron  or  other 
metal,  used  for  various  purposes  of 
fastening,  planking,  &c. 
Bolt  auger,  an  auger  of  a  larger  size, 

used  by  ship-bidlders 
Bolt  rope,  the  rope  to  which  the  edges 
of  sails  are  sewed,  to  strengthen 
them 
Bolt-acrewing  machine,  a  machine  for 
screwing  bolts,  by  fixing  the  bolt- 


head  to  a  revolving  chuck,  and 
causing  the  end  which  it  is  required 
to  screw  to  enter  a  set  of  dies,  which 
advance  as  the  bolt  revolves 

Bolts,  long  cylindrical  bars  of  iron  or 
copper,  used  to  secure  or  unite  the 
different  parts  of  a  vessel 

Bolts,  the  principal  iron-woik  forfitft 
ening  and  securing  the  ship 

Bolts,  large  iron  pins 

Bomb-vessel,  a  strong-bnilt  vessel  car< 
rying  heavy  metal  for  bombardmenl 

Bond,  in  masonry,  is  that  connection 
of  lapping  the  stones  upon  one  anO' 
ther  in  the  carrying  up  of  the  woili 
so  as  to  form  an  inseparable  masi 
of  building 

Bond,  in  bricklaying  and  masonry,  ii 
the  arrangementorpladng  of  bricks, 
&c.,  so  as  to  form  a  secure  mast 
of  building 

Bonders,  Bond  stones,  Binding  stones^ 
stones  which  reach  a  considerabk 
distance  into,  or  entirely  through, 
a  wall,  for  the  purpose  of  binding 
it  together 

Bond  stones,  are  pkced  in  the  thick- 
ness  of  a  wall,  at  right  angles  to  iti 
face,  to  bind  securely  together 

Bond  timber,  pieces  of  timber  used  tc 
bind  in  brick-work  especially.  Tht 
naked  flooring  being  laid,  in  cairf- 
ing  up  the  second  story  bond  tim- 
b^  must  be  introduced  opposite 
to  all  horizontal  mouldings,  as  basei 
and  surfaces.  It  is  also  customarj 
to  put  a  row  of  bond  timber  in 
the  nuddle  of  the  story,  oi  greatei 
strength  than  those  for  the  bases 
and  surfaces 

Bone-brown  and  Ivory-brown,  pro- 
duced by  torrefying  or  roasting 
bone  and  ivory,  till,  by  partiaJ 
charring,  they  become  of  a  brown 
colour  throughout 
Boning,  in  carpentry  and  masonry,  tw 
art  of  making  a  plane  surface  oj 
the  guidance  of  the  eye:  joiners 
try  up  their  work  by  boning  with 
twostraight-edges, which  determine 
whether  it  be  in  or  out  of  winding, 
that  is  to  say,  whether  the  8Ui£»ce 
be  twisted  or  a  plane 
Bonnet,  in  navigation,  an  additional 


BON 


B0RIN6.MACHINE. 


BOT 


piece  of  canvas  attached  to  the  foot 
of  a  jib,  or  a  schooner's  foresail, 
by  ladngs,  taken  off  in  bad  weather 
BtnmetSj  the  cast-iron  plates  which 
coyer  the  openings  in  the  valve- 
chambers  of  a  pump :  the  openings 
are  made  so  that  ready  access  can 
be  had  when  the  valves  need  re- 
pairing 
Boom,  in  ship-bnilding,  a  bng  pole 
mn  out  from  different  places  in  the 
ship,  to  extend  the  bottoms  of  par- 
ticobyr  sails,  as  jib-boom,  flying- 
boom,  studdUng-sails-boom,  &c. 
Boomkm,  in  ship-buildmg,  a  beam  of 
tunber  projecting  from  each  bow 
of  a  ship,  to  extend  the  clue  or 
lower  comer  of  the  foresail  to  wind- 
ward 
BoatK,  a  stall  or  standing  m  a  £ur  or 

market 
BooUtuppmgy  scraping  off  the  grease, 
or  other  matter,  which  may  be  on 
a  vessel's  bottom,  and  daubing  it 
over  vdth  tallow 
Borax,  in  chemistry,  a  salt  in  appear- 
ance like  crystals  of  alum;  an  ar- 
tificial salt  used  for  soldering  metals 
BorceTf  an  instrument  of  iron,  steel- 
pointed,  to  bore  holes  in  large  rocks, 
in  order  to  blow  them  up  with  gun- 
powder 
Bord,  anciently  a  cottage 
Bore,  in  hydrography,  a  sudden  and 
abrupt   influx  of  the  tide  into  a 
river  or  narrow  strait 
Boreas,  the  north  wind 
Borer,  a  boring  instrument,  with  a 
piece  of  steel  at  the  end,  called  a 
boring-bolt 
Borinff,  the  art  of  perforating  or  mak- 
ing a  hole  through  any  solid  body; 
as  boring  the  earth  for  water;  bor- 
ing water-pipes,  either  wood,  iron, 
zinc,  or  lead ;  boring  cannon,  &c. 
Boring,  Modem  steam  engines  depend 
on  the  improved  method  of  boring 
their  cylinders.   The  cylinder  to  be 
bored  is  firmly  fixed  with  its  axis 
parallel  to  the  direction  in  which  the 
borer  is  to  move :  the  cutting  ap- 
paratus moves  along  a  bar  of  iron  ac- 
curately turned  to  a  cylindrical  form 
Boring-bar,  a  bar  of  a  small  horizontal 


boring  machine :  it  is  used  for  bor- 
ing the  brasses  of  plummer-blocks, 
by  means  of  a  cutter  fixed  in  it 

Boring-eoUar,  in  turning,  a  machine 
having  a  pUtte  with  conical  holes  of 
different  diameters:  the  plate  is 
moveable  upon  a  centre,  which  is 
equidistant  from  the  centres  or 
axes  of  the  conical  holes ;  the  axes 
are  placed  in  the  circumference  of 
a  circle.  The  use  of  the  boring- 
collar  is  to  support  the  end  of  a 
long  body  that  is  to  be  turned  hol- 
low, and  which  would  otherwise  be 
too  long  to  be  supported  by  a  chuck 

Boring  lathe,  a  lathe  used  for  boring 
wheels  or  short  cylinders.  The 
wheel  or  cyUnder  is  fixed  on  a  large 
chuck,  screwed  to  the  mandril  of  a 
lathe 

Boring  machine,  a  machine  for  turn- 
ing the  inside  of  a  cylinder 

Boron,  in  chemistry,  is  an  oUve-green 
powder,  which,  heated  out  of  the 
air,  becomes  harder,  and  darker  in 
colour:  it  bums  brilliantly  when 
heated  in  air  or  oxygen,  forming 
boradc  add 

Boss,  a  sculptured  keystone  or  carved 
piece  of  wood,  or  moulded  plaster, 
placed  at  intervals  of  ribs  or  groins 
in  vaulted  and  flat  roofr  of  Gothic 
structures 

Boss,  a  short  trough  for  holding  mor- 
tar when  tiling  a  roof:  it  is  hung 
to  the  laths 

Bossage,  projecting  stones  laid  rough 
in  building,  to  be  afterwards  cut 
into  mouldings  or  ornaments 

Botany  Bag  oak,  resembling  in  colour 
full  red  mahogany,  is  used  as  veneer 
forthe  backs  of  brushes,  turnery,  &c. 

Bottle-glass,  a  composition  of  sand 
and  lime,  day,  and  alkaline  ashes  of 
any  kind 

Bottom  -  certain,  a  superintendent 
over  the  miners  in  the  bottoms 

Bottom  heat,  artifidal  temperature, 
produced  in  hot-houses 

Bottom-Uft,  in  mining,  the  deepest  or 
bottom  tier  of  pumps 

Bottom-rail,  in  joinery,  the  lowest 
rail  of  a  door 

Bottoms,  in  mining,  the  deepest  work- 


BOT 


BOWER  CABLES. 


BO\« 


ing  parts  of  a  mine^  wrought  either 
by  sloping,  driving,  or  otherwise 
breaking  the  lode 

Bottoms  in  fork.  In  Cornwall,  when 
all  the  bottoms  are  unwatered,  they 
say,  'the  bottoms  are  in  fork;' 
and  to  draw  out  the  water  from 
them,  or  any  dippa,  or  any  other 
particular  pfurt  of  a  mine,  is  said  to 
be  'forking  the  water;'  and  when 
accomplished,  such  dippa,  &c.,  is 
*  in  fork/  Likewise  when  an  en- 
gine  has  drawn  out  all  the  water, 
they  say,  *  the  engine  is  in  fork  * 

Bottony;  in  heraldry,  a  cross-bottony 
is  terminated  at  each  end  in  three 
buds,  or  knots,  or  buttons 

Boudoir  t  a  small  retiring-room 

Bougetf  in  heraldry,  the  representa- 
tion of  a  vessel  for  carrying  water 

BoulderSf  fragments  of  rocks  trans- 
ported by  water,  and  found  on  the 
sea-shore 

Boulder  wallst  walls  built  of  the  above 

Boultinej  in  architecture,  a  convex 
moulding  whose  periphery  is  a 
quarter  of  a  circle,  next  below  the 
plinthinthe  Doric  andTuscan  orders 

Bounds f  in  mining,  signifies  the  right 
to  tin  ore  over  a  given  district 

Boursci  a  public  edifice  for  the  as- 
semblage of  merchants  to  consult 
on  matters  of  business  or  money 

Boutant;  in  architecture,  an  arc-bou- 


tant is  an  arch,  or  buttress,  serving 
to  sustain  a  vault,  and  whicli  is  it^ 
self  sustained  by  some  strong  'wal 
or  massive  pile 

BovOf  anciently  a  wine-cellar 

Bovey  coalf  wood-coal  found  at  Bovey 
in  Devonshire 

Bow  f  the  roundpart  of  the  ship  forwarc 

Bow,  anciently  an  arch  or  gate^ray 

Bow  compass,  for  drawing  arclies  o: 
very  large  aisles;  it  consists  of  i 
beam  of  wood  or  brass  with  three 
long  screws  that  bend  a  lath  o: 
wood  or  steel  to  any  arch.  The 
term  also  denotes  smiall  compasses 
employed  in  describing  arcs  toe 
small  to  be  accurately  dra^vn  b^ 
the  common  compasses 

Bower,  anciently  a  small  enriched 
chamber  for  ladies;  a  private  room, 
or  parlour,  in  ancient  castles  and 
mansions 

Bower,  a  working  anchor,  the  cahle  of 
which  is  bent  and  veered  through 
the  hawse-hole 

Bower,  in  navigation,  two  anchors 
thus  named  from  their  being  car- 
ried at  the  bow 

Bower  cables,  for  ships. 

Table  showing  the  different  kinds 
of  best  bower  cables  at  present  em- 
ployed in  the  British  navy,  with  the 
corresponding  iron  cables,  and  the 
proof-strain  for  each : 


BAtes  of  Ships. 


Best  bower  hempen 
cables,  100  fathoms. 


Cir- 
cum. 


First-rate,  larre  . 
middle 
small 
Second-rate    . 
Third,  large    . 
small    . 
Fourth,  60  guns 
58   do. 
50   do. 
Fifth,     48   do. 
46   do. 
42   do. 

Sixth,     28   do. 

Ship,  sloop 
Brig,  large .    . 

Ditto,  small    . 
~T8 


} 


m. 
25 
24 
23 
23 
23 
22 
21 

19 

184 

18 

144 

134 
134 

11 


Weight. 


cwt.  qr.  tb. 

114    2      7 

105    2    17 

96    2    27 


96 
96 
89 
80 
66 


2 
2 
0 
0 
0 


27 
27 
12 
22 
21 


62  1  14 

58  2  6 

66  0  1 

38  0  21 

33  0  10 

33  0  10 

21  2  15 


■ 


Number 

of 
threads 
in  each. 


3240 

2988 

2736 1 

2736}. 

2736  J 

26201 

2268  J 

1872 

1764 

1666 

1664 

1080 

936 
936 

612 


tons.  cwt.  qr. 


Breaking 

strain  by 

experiment. 


114 
89 


0     0 
0*0 


63     0     0 


40      0      0 


Diameter  and 

weight  of  the  bolt 

of  the  iron  cable 

substituted  for 

the  preceding. 


Strain 
for  the' 
proof. 


24  inches. 
''21 8  cwt. 


r     S  inches. 
1 186  cwt.  2  qra. 
1|  inch. 
170  cwt.  2  qrs. 

If  iach. 
145  cwt.  3  qra. 

If  inch. 

87  cwt.  2  qra. 

14  inch. 

74  cwt.  3  qra. 

14  inch. 

61  cwt.  1  or. 


tons. 
}8. 

}72 

}63 

}34 
}28 
}23 


BOW 


BRACKETS. 


BRA 


From  the  preceding  Table  the  un- 
mense  advantage  of  iron  cables  will 
be  distinctly  seen,  and  particularly 
when  it  is  considered  that  a  hempen 
cable,  on  a  rocky  bottom,  is  de- 
stroyed in  a  few  months,  while  the 
other  will  sustain  no  perceptible 
injury. 

Bawericj  in  the  East  Indies,  a  well 
descended  by  steps 

Bow-grace,  a  frame  of  old  rope,  or 
juiUc,  placed  romid  the  bows  and 
sides  of  a  vessel,  to  prevent  the  ice 
from  injuring  her 

Bow-Une,  in  navigation,  a  rope  leading 
forward  from  die  leach  of  a  square 
sail,  to  keep  the  leach  well  oat,  when 
sailing  close-hauled 

Bowlt  of  silver  were  used  as  drinking- 
glasses  are  now,  before  the  intro- 
duction of  glass  for  such  purposes  ; 
they  were  of  small  sizes,  in  *  nests' 
fitting  one  within  another.  Of  the 
larger  sized  bowl,  the  most  distin- 
guished are  the  mazer  and  the 
wassail.  Mazer  is  a  term  applied 
to  large  goblets,  of  every  kind  of 
mater^;  but  the  best  authors 
agree  that  its  derivation  is  from 
maeaer,  which,  in  Dutch,  means 
maple ;  and  therefore  that  a  mazer 
bowl  is  one  formed  of  maple  wood 

Bow-saw,  a  saw  used  for  cutting  the 
thin  edges  of  wood  into  curves 

Bowse,  to  pull  upon  a  tackle 

Bowsprit,  m  ship-buildmg,  a  large 
boom  or  mast  which  projects  for- 
ward over  the  stem  to  cany  sail 

Bowtel,  the  shaft  of  a  clustered  pillar, 
or  a  shaft  attached  to  the  jambs  of 
a  door  or  window 

Box,  for  mitring,  a  trough  for  cutting 
mitres :  it  has  three  sides,  and  is 
open  at  the  ends,  with  cuts  in  the 
vertical  sides  at  angles  of  45^  with 
ihem 

Box-drain,  an  underground  drain  built 
of  brick  and  stone,  and  of  a  rectan- 
gular section 

Box  of  a  rib-saw,  two  thin  iron  phites 
fixed  to  a  handle,  in  one  of  which 
plates  an  opening  is  made  for  the 
reception  of  a  wedge,  by  which  it 
is  filed  to  the  saw 


59 


BoX'haui,  to  veer  a  ship  in  a  manner 

when  it  is  impossible  to  tack 
Box  the  compass,  to  repeat  thirty- 
two  points  of  the  compass  in  order 
Boxing-off,  throwing  the  head  sails 
a-back,  to  force  the  ship's  head  ra- 
pidly off  the  wind 
Boxings  of  a  window,  the  cases  oppo- 
site each  other  on  each  side  of  a 
window,  into  which  the  shutters 
are  folded 
Box  wood  is  of  a  yellow  colour,  in- 
clining to  orange ;  is  a  sound  and 
useful  wood,  measuring  from  2  to 
6  feet  long,  and  2^  to  12  inches  in 
diameter :  it  is  much  used  by  wood 
engravers;  for  clarionets,  flutes;  for 
carpenters'   rules,  drawing-scales, 
&c.      Much  of  it  comes  from  Box 
Hill,  in  Surrey,  and  from  several 
districts  in    Gloucestershire,    also 
from  other  parts  of  Europe 
Boziga,  anciently  a  house  or  dwelling 
Brace,  a  piece  of  slanting  timber,  used 
in  truss  partitions,  or  in  framed 
roofs,  in  order  to  form  a  triangle, 
and  thereby  rendering  the  frame 
immoveable :  when  a  brace  is  used 
by  way  of  support  to  a  rafter,  it  is 
called  a  strut :  braces  in  partitions 
and  span  roofs  are  always,  or  should 
be,  disposed  in  pairs,  and  placed  in 
sopposite  directions 
Brace,  ah^justrument  into  which  a 
vernier  is  fixed ;   also  part  of  the 
press-drill 
Brace,  a  rope  by  which  a  yard  is  turned 

about 
Braces,  that  security  for  the  rudder 
which  is  fixed  to  the  stem-post  and 
to  the  bottom  of  a  ship 
Bracket  plummer-block,  a  support  for 
a  shaft  to  revolve  in,  formed  so  that 
it  can  be  fixed  vertically  to  the 
frame  of  a  machine,  or  to  a  wall 
Brackets,  ornaments :  the  hair  bracket 
in  ship-building  is  the   boundary 
of  the  aft-part  of  the  figure  of  the 
head,  the  lower  part  of  which  ends 
.   vrith  the  fore-part  of  the  upper 
cheek.     The  console  bracket  is  a 
hght  piece  of  ornament  at  the  fore- 
part of  the  quarter-gallery,  some- 
times called  a  canting-hose 


i>tf.i..iiiit-. 

.p™of.j 

^.n:s- 

J  •  •*" 

■      'V 

-     :,«. 

>-  ! 

a— 

t'ifS-'r 

)~  1 

BOW 


BRACKETS. 


BRA 


From  the  preceding  Table  the  im- 
mense advantage  of  iron  cables  will 
be  distinctly  seen,  and  partiailarly 
when  it  is  considered  thttt  a  hempen 
cable,  on  a  rocky  bottom,  is  de- 
stroyed in  a  few  months,  while  the 
other  will  suatain  no  perceptible 
injury. 

Bowericy  in  the  East  Indies,  a  well 
descended  by  steps 

Bow-grace,  a  frame  of  old  rope,  or 
junk,  placed  romid  the  bows  and 
sides  of  a  vessel,  to  prevent  the  ice 
from  injuring  her 

Bow-tine,  in  navigation,  a  rope  leading 
forward  from  die  leach  of  a  square 
saU,  to  keep  the  leach  well  oat,  when 
sailing  close-hauled 

Bowls  of  silver  were  used  as  drinking- 
glasses  are  now,  before  the  intro- 
duction of  glass  for  such  purposes ; 
they  were  oi  small  sizes,  in  *  nests' 
fitting  one  within  another.  Of  the 
larger  sized  bowl,  the  most  distin- 
guished are  the  mazer  and  the 
wassaiL  Mazer  is  a  term  applied 
to  large  goblets,  of  every  khid  of 
material;  but  the  best  authors 
agree  that  its  derivation  is  from 
maeser,  which,  in  Dutch,  means 
maple  i  and  therefore  that  a  mazer 
bowl  Ib  one  formed  of  maple  wood 

Bow-saw,  a  saw  used  for  cutting  the 
thin  edges  of  wood  into  curves 

Bowse,  to  pull  upon  a  tackle 

Bowsprit,  in  ship-building,  a  large 
boom  or  mast  which  projects  for- 
ward over  the  stem  to  carry  sail 

Bowtel,  the  shaft  of  a  clustered  pillar, 
or  a  shaft  attached  to  the  jambs  of 
a  door  or  window 

Box,  for  mitring,  a  trough  for  cutting 
mitres:  it  has  three  sides,  and  is 
open  at  the  ends,  with  cuts  in  the 
vertical  sides  at  angles  of  45^  with 
them 

Box-drain,  an  underground  drain  built 
of  brick  and  stone,  and  of  a  rectan- 
golar  section 

Box  of  a  rib-saw,  two  thin  iron  plates 
fixed  to  a  handle,  in  one  of  which 
plates  an  opening  is  made  for  the 
reception  of  a  wedge,  by  which  it 
is  fixed  to  the  saw 


59 


BoX'hatU,  to  veer  a  ship  in  a  manner 

when  it  is  impossible  to  tack 
Box  the  compass,  to  repeat  thirty- 
two  points  of  the  compass  in  order 
Boxmg-off,  throwing  the  head  sails 
a-back,  to  force  the  ship's  head  ra- 
pidly ofif  the  wind 
Boxings  of  a  window,  the  cases  oppo- 
site each  other  on  each  side  of  a 
window,  into  which  the  shutters 
are  folded 
Box  wood  is  of  a  yellow  colour,  in- 
clining to  orange ;  is  a  sound  and 
useful  wood,  measuring  from  2  to 
6  feet  long,  and  2i  to  12  inches  in 
diameter :  it  is  much  used  by  wood 
engravers;  fw  clarionets,  flutes;  for 
carpenters'   rules,  drawing-scales, 
&c.      Much  of  it  comes  from  Box 
HOI,  in  Surrey,  and  from  several 
districts  in    Gloucestershire,    also 
from  other  parts  of  Europe 
Boziga,  anciently  a  house  or  dwelling 
Brace,  a  piece  of  slanting  timber,  used 
in  truss  partitions,  or  in  fr^ed 
roofs,  in  order  to  form  a  triangle, 
and  thereby  rendering  the  frame 
immoveable :  when  a  brace  is  used 
by  way  of  support  to  a  rafter,  it  is 
called  a  strut :  braces  in  partitions 
and  span  roofs  are  always,  or  should 
be,  disposed  in  pairs,  and  placed  in 
•^posite  directions 
Brace,  air^instrument  into  which  a 
vernier  is  fixed ;  also  part  of  the 
press-drill 
Brace,  a  rope  by  which  a  yard  is  turned 

about 
Braces,  that  security  for  the  rudder 
which  is  fixed  to  the  stem-post  and 
to  the  bottom  of  a  ship 
Bracket  pJummer-block,  a  support  for 
a  shaft  to  revolve  in,  formed  so  that 
it  can  be  fixed  vertically  to  the 
frame  of  a  machine,  or  to  a  wall 
Brackets,  ornaments :  the  hair  bracket 
in  ship-building  is  the  boundary 
of  the  aft-part  of  the  figure  of  the 
head,  the  lower  part  of  which  ends 
-  with  the  fore-part  of  the  upper 
cheek.     The  console  bracket  is  a 
hght  piece  of  ornament  at  the  fore- 
part of  the  quarter-gallery,  some- 
times caQed  a  canting-hose 


BRA 


BRAMAH'S  HYDROSTATIC  PRESS. 


BRA 


BraeketSt  tbe  cheeks  of  the  carriage 
of  a  mortar;  a  cramping.iron  to 
^ttay  timber-work;  also  stays  set 
under  a  shelf,  to  support  it 

Bracket -stain,  **  The  same  method 
must  be  observed,  with  regard  to 
taking  the  dimensions  and  laying 
down  the  plan  and  section,  as  in 
dogling-stairs.  In  all  stairs  what, 
ever,  after  having  ascertained  the 
number  (tf  steps,  take  a  rod  the 
height  of  the  story,  from  the  surface 
of  the  lower  floor  to  the  surface  of 
the  upper  floor ;  divide  the  rod  into 
as  many  equal  parts  as  there  are  to 
be  risers ;  then,  if  you  have  a  level 
surface  to  work  upon  below  the 
stairs,  try  each  one  of  the  risers  as 
you  go  on :  this  will  prevent  any 
defect/' 

Bradf  a  small  nail  with  a  projecting 
head  on  one  edge 

Brad-awl,  the  smallest  boring  tool 
usedbya  carpenter;  its  handle  is  the 
frustmm  of  a  cone  tapering  down- 
wards ;  the  steel  part  is  also  coni- 
cal,  but  tapering  upwards,  and  the 
cutting  edge  is  the  meeting  of  two 
basils,  ground  equally  from  each 
side 

Braih,  in  navigation,  ropes  by  which 
the  foot  or  lower  comers  of  fore 
and  aft  sails  are  hauled  up 

Brake,tYie  apparatus  used  for  retarding 
the  motion  of  a  wheel  by  friction 
upon  its  periphery 

Brake,  the  handle  of  a  ship's  pump 

Brake,  a  machine  used  in  dressing  flax 

Brake-wheel,  the  wheel  acted  upon  by 
a  brake 

Bratnah*8  hydrostatic  pren  consists  in 
the  application  of  water  to  engines, 
so  as  to  cause  them  to  act  with  im- 
mense force ;  in  others,to  communi- 
cate the  motion  and  powers  of  one 
part  of  a  machine  to  some  other 
part  of  the  same  machine 

This  press  was  constructed  in 
Woolvrich  dockyard  for  testing 
iron  cables,  and  the  strain  is  pro- 
duced by  hydrostatic  pressure :  its 
amount  is  estimated  by  a  system 
olf  levers  balanced  on  knife  edges, 
which  act  quite  independently  of 

60 


the  strain  upon  the  machine, 
and  exhibit  sensibly  a  change  of 
pressure  of  ^h  <rf  a  ton,  even 
when  the  total  strain  amounts  to 
100  tons. 

This  proving  machine  was  con- 
structed by  Messrs.  Bramah,  of 
Pimlico,  and  is  doubtless  one  of 
the  most  perfect  of  the  kind  which 
has  been  executed.  It  consists 
of  two  cast-iron  sides,  cast  m 
lengths  of  9i  feet  each,  with  pro- 
per flanches  for  abutting  against 
each  other,  and  for  fixing  the  whole 
to  sleepers  resting  on  a  secure  stone 
foundation.  The  whole  length  of 
the  fiwne  is  104^  feet,  equal  to  ^th 
the  length  of  a  cable  for  a  first-rate ; 
so  that  the  cables  are  tested  in  that 
number  of  detached  lengths,  which 
are  afterwards  united  by  shackle- 
bolts.  The  press  is  securely  bolted 
down  at  one  end  of  the  fnmt^ 
and  the  cylinder  is  open  at  both 
ends.  The  solid  piston  is  5^  inches 
in  diameter  in  fnmi  and  lOi  inches 
behind,  so  that  the  surfiiu^  of  press- 
ure is  the  difference  of  the  two,  viz. 


(?llL?5*) 


X  '7854  »  65|  inches. 


The  system  of  levers  hung  oo 
knife  edges  is  attached  to  the  other 
end  of  the  frame,  and  the  cable  is 
attached  by  bolt-links  to  this  and 
to  the  end  of  the  piston-rod.  The 
levers  being  properly  balanced,  and 
the  oible  attached  to  a  short  ann 
rising  above  the  axis,  this  draws  the 
other  arm  downv^ards;  and  at  a  dis- 
tance equal  to  twelve  times  the  short 
arm,  is  a  descending  pin  and  ball, 
acting  in  a  cup  placed  on  the  upper 
part  of  the  arm  of  the  second  lever, 
and  this  again  acts  on  athird.  The 
first  two  levers  are  under  the  floor, 
and  piM  ultimately  into  an  adjacent 
nMmifWliere  a  scale  carryingweights 
la  oonvenientlyplaced,  and&ewhole 
combinationiB  suchthateverypound 
in  the  scale  is  the  measure  of  a  ton 
■train:  the  whole  acts  with  such 
precision  that  ^Stt  of  a  pound,  more 
or  less,  in  the  scale,  very  sensibly 


BRA. 


BRASSES. 


BRE 


affects  the  balance.     At  the  same 
place  is  situated  a  scale,  acted  upon 
by  the  water  pressure  from  the 
cbarge-pipe  of  the  press,  and  the 
valve  in  this  pipe  is  of  such  dimen- 
sioiis  that,  tc^ether  with  the  lever 
by  which  it  acts,  the  power  is  again 
such  that  a  pound  should  balance 
a  ton ;  but  the  firic^on  is  here  so 
great  that  it  requires  several  pounds 
to  make  a  sensible  change  in  the 
apparent  balance,  and  for  this  rea^ 
son  this  scale  is  never  used.    The 
forcxng-pumps  are  in  another  adja- 
cent room,  and  are  worked  by  han-  j 
dies,  after  the  manner  of  a  fire  en- 
gine.  At  first,  six  pistons  are  acting, 
and  the  operation  proceeds  quickly; 
but  as  the  pressure  and  strains  in- 
crease, the  barrels  are  su^Msessivcly 
shut  off,  tin  at  length  the  whole 
power  of  the  men  is  employed  on 
one  pair  of  pumps  only,  and  on  this 
theaction  is  continued  till  the  proof- 
strain  is  brought  on  the  cable.    A 
communication  is  then  opened  be- 
tween the  cistern  and  cylinder,  and 
everything  is  again  restored  to  equi- 
librium. 
Braneh,  in  mining,  a  leader,  string, 
or  rib  of  ore,  that  runs  in  a  lode ; 
or  if  a  lode  is  divided  into  several 
strings,  they  are  called  branches, 
whether  they  contain  ore  or  not : 
likewise  strings  of  ore  which  run 
transversely  into  the  lode  are  called 
branches;  and  so  are  all  veins  that 
are  small,  dead  or  alive,  t.  e.  whe- 
ther they  contain  ore  or  not 
Branched'Warky   carved  and  sculp- 
tured leaves  and  branches  in  mo- 
numents and  friezes 
BroncAea,  anciently  the  ribs  of  groined 

edlings 
Brandishing  or  BrattiaMng,  a  term 

used  for  carved  work,  as  a  crest, 

battlement,  or  other  parapet 
Brmubitht  a  fence  or  rail  round  the 

opening  of  a  well 
BratBf  a  factitious  metal,  made  of 

copper  and  zinc 
Brow,  in  the  middle  ages,  a  plate  of 

metal  inserted  or  affixed  to  a  flat 
gravestone 

61 


BraMe9,«^p«/cAra/,monumentalplates 
of  brass  or  mixed  metal,  anciently 
called  latten,  inlaid  on  large  slabs 
of  stone,  which  usually  form  part 
of  the  pavement  of  a  church,  and 
represent  in  their  outline,  or  by 
lines  engraved  upon  them,  the 
figure  of  the  deceased 

Brattishmjf,  anciently,  carved  open 
work 

Brajff  anciently  a  bank  or  earthen 
mound 

Brazedf  in  heraldry,  three  chevrons 
clasping  one  another 

Bnail  woodf  the  wood  of  the  Caesal- 
pinia  crista,  which  yields  a  red  dye: 
it  is  imported  principally  from  Per- 
nambuco :  the  tree  is  large,  crooked, 
and  knotty;  and  the  bark  is  thick, 
and  equals  the  third  or  fourth  of 
its  diameter.  Its  principal  use  is 
for  dyeing :  the  best  pieces  are  se- 
lected for  violin-bows  and  turnery 

Braziktto  wood  is  of  a  ruddy  orange 
colour,  principally  used  for  dyeing, 
and  for  turnery  and  violin-bows 

Brazing,  the  soldering  together  of 
edges  of  iron,  copper,  brass,  &c., 
with  an  alloy  of  brass  and  zinc 
called  spelter  solder 

Breaehittfff  a  strong  rope  used  to  se- 
cure the  breech  of  a  gun  to  the 
ship's  side 

Breadth  is  applied  to  painting  when 
the  colours  and  shadows  are  broad 
and  massive,  such  as  the  lights  and 
shadows  of  the  drapery;  and  when 
the  eye  is  not  checked  and  dis. 
tracted  by  numerous  little  cavities, 
but  glides  easily  over  the  whole. 
Breadth  of  colouring  is  a  promi- 
nent character  in  the  painting  of 
all  great  masters 

Break,  in  shipping.  To  break  hUk,  is 
to  begin  to  unload 

Break,  a  projection  or  recess  from  the 
snrfoce  or  wall  of  a  building 

Break  Joint,  constructively,  to  dis- 
allow two  joints  to  occur  over  each 
other 

Breaker,  a  small  cask  containing 
water 

Breaking  down,  in  sawing,  is  dividing 
the  baulk  into  boards  or  planks 


BRE 


BRICKS. 


BRI 


Breaking  joints  in  joinery,  is  not  to 
allow  two  joints  to  come  together 

Breakwater,  a  human  contrivance  to 
ward  ofif  and  diminish  the  force  of 
waves,  to  protect  harbours,  stations, 
&c.,  from  the  violence  of  tempes- 
tuous gales.  Some  stupendous 
works  have  been  executed  for  these 
purposes,  especially  that  at  Ply. 
mouth,  by  the  great  Sir  John  Rennie 

Breammfff  cleaning  a  ship's  bottom 
by  burning 

Breast,  in  mining,  the  face  of  coal> 
workings 

Breast-fast,  a  rope  used  to  confine  a 
vessel  sideways  to  a  wharf  or  to 
some  other  vessel 

Breast-hooks,  pieces  of  compass  or 
knee-timber,  placed  withinside  a 
ship,  to  keep  the  bows  together. 
The  deck-holes  are  fayed  to  the 
timbers,  and  placed  in  the  direction 
of  the  decks :  the  rest  are  placed 
one  between  each  deck,  and  as 
many  in  the  hold  as  are  thought 
needful;  all  of  which  should  be 
placed  square  with  the  body  dl^  the 
ship,  and  fayed  on  the  planks. 
Breast-hooks  are  the  chief  security 
to  keep  the  ship's  bows  together ; 
therefore  they  require  to  be  very 
strong  and  well- secured 

Breast-knees,  those  placed  in  the 
forward  part  of  a  vessel,  across  the 
stem,  to  unite  the  bows  on  each 
side 

Breast-plate,  that  in  which  the  end 
of  the  drill  opposite  the  boring  end 
is  inserted 

Breast-rail,  the  upper  rail  of  the  bal- 
cony or  of  the  breast-work  on  the 
quarter-deck 

Breast-rope,  a  rope  passed  round  a 
man  in  chains,  while  sounding 

Breast-wheel,  in  mill-work,  a  form  of 
water-wheel  in  which  the  water  is 
delivered  to  the  float-boards  at  a 
point  somewhat  between  the  bot- 
tom and  top.  Buckets  are  seldom 
employed  on  breast-wheels 

Breast-work,  the  stantients  with  rails 
on  the  quarter-deck  and  forecastle. 
The  breast-work  fitted  on  the  up- 
per  deck  of  such  ships  as  have  no 

62" 


quarter-deck  serves  to  disting^sh 
the  main  deck  from  the  quarter-deck 

Breech,  the  angle  of  knee-timber,  the 
inside  of  which  is  called  the  throat 

Breeze,  small  ashes  and  cinders  used 
instead  of  coal  for  the  boming  of 
bricks 

Breort-weallft  anciently,  a  breast-high 
wall 

Bressummer,  a  beam  supporting  a  su- 
perincumbent part  of  an  exterior 
wall,  and  running  longitudinally 
below  that  part 

BretachuB,  anciently,  wooden  toipvers, 
attached  ^o  fortified  towns 

Brick,  *  *  *  "  Let  us  make  brick, 
and  bum  them  thoroughly.  And 
they  had  brick  for  stone,  and  slime 
had  they  for  mortar." — Gen.  xL  3 

Bricks  are  a  kind  of  factitious  stone, 
composed  of  argillaceous  earth,  and 
frequently  a  certain  portion  of  sand 
and  cinders  of  sea  coal  (called 
breeze),  tempered  together  ^with 
water,  dried  in  the  sun,  and  burnt 
in  a  kiln,  or  in  a  heap,  or  stack, 
called  a  clamp.  For  good  brick- 
making,  the  earth  should  be  of  the 
purest  kind,  dug  in  autumn,  and 
exposed  during  the  winter's  frost : 
this  allows  the  air  to  penetrate, 
and  divide  the  earth  particles,  and 
facilitates  the  subsequent  opera^ 
tions  of  mixing  and  tempering 

The  Romans  made  bricks  of  va- 
rious sizes,  from  2  feet  to  1  foot  in 
length,  from  7  inches  to  9  inches  in 
breadth,  and  from  3^  inches  to  1^ 
in  thickness.  Roman  bricks  found 
in  the  old  Roman  wall  at  Veru- 
1am,  compared  with  modem  bricks, 
showed  the  superiority  of  the  old 
to  the  new;  the  Roman  bricks 
being  lighter  and  better  burnt 
than  the  modem. 

The  brick  remains  of  the  period 
of  the  Roman  empire  are  more  en-. 
tire  than  the  stone.  Bricks  were 
found  at  Toulouse,  quite  sharp  at; 
the  edges,  and  not  altered  by  time  • 
they  measured  14  inches  long-, 
9  inches  broad,  and  1^  thidc. 
These  bricks  formed  the  founda.^ 
tion  all  around  the  building.    The 


BRI 


BRIDGE. 


BRI 


arches  were  formed  of  them  for 
entrances ;  and  round,  large,  water- 
worn  pebbles  of  quartz  with  mor- 
tar,  formed  the  wsdls  of  the  circus, 
resting  on  the  brick  arches. 

Mr.  Layardy  in  his  work  on  Ni- 
nereh,  says — ' '  The  soil,  an  alluTial 
deposit,  was  rich  andtenadons:  the 
builders  moistened  it  with  water, 
and  adding  a  little  chopped  straw, 
that  it  might  be  more  firmly  bound 
together,  theyformed  it  into  squares, 
wMch,  when  dried  by  the  heat  of 
the  sun,  served  them  as  bricks.  In 
that  climate,  the  process  required 
but  two  or  three  days.  Such  were 
the  earliest  building  materials,  and 
as  they  are  used  to  this  day,  almost 
exclusively,  in  the  same  country. 

*'  The  Assyrians  appear  to  have 
made  much  less  use  of  bricks  baked 
in  the  furnace  than  the  Babylonians; 
no  masses  of  brick-work,such  as  are 
every  where  found  in  Babylonia 
Proper,  existing  to  the  north  of  that 
province.  Common  clay  moistened 
with  water,  and  mixed  with  a  little 
stubble,  formed,  as  it  does  to  this 
day,  the  mortar  used  in  buildings ; 
but,  however  simple  the  materials, 
they  have  successfully  resisted  the 
ravages  of  tiuae,  and  still  mark  the 
stupendous  nature  of  the  Assyrian 
structures. 

"  This  mode  of  brick-making  is 
described  by  Sanchoniathon :   The 
people  of  Tyre  invented  the  art  of 
brick-making   and  of  building  of 
huts;  afterthem  came  two  brothers : 
one  of  them,  Chrysor  or  Hyphaes- 
tus,  was  the  first  who  sailedin  boats; 
his  brother  invented  the  way  of 
making  walls  with  bricks.    F^om 
thegeneration  werebomtwo  youths, 
one  called  Technites  and  the  other 
Genius  Autochthon.    They  disco- 
vered the  method  of  mingling  stub- 
ble with  the  loam  of  the  bricks,  and 
drying  them  in  the  sun ;  they  also 
invented  tiling." 
Bricka.    Some  of  Palladio's  finest  ex- 
amples are  of  brick :  the  cortile  of 
the  Carit^  at  Venice  is  an  instance. 
The  interiora  of  the  Redentore  and 


St.  Giorgio,  in  the  same  city,  have 
but  a  coat  of  plaster  on  them ;  the 
beautiful  Palazzo  Thiene  at  Vicenza, 
at  least  that  part  which  was  exe- 
cuted, is  left  with  its  rock-worked 
basementinbrick-workchipped  out. 
Form  alone  fastens  on  the  mind  in 
works  of  art :  the  rest  is  meretri- 
cious, if  used  as  a  substitute  to  su- 
persede this  grand  desideratum 
Brici  ajpe,  used  for  axing  off  the 
soffits  of  bricks  to  the  saw-cut- 
tings,  and  the  sides  to  the  lines 
drawn:  as  the  bricks  are  always 
rubbed  smooth   after  axing,   the 
more  truly  they  are  axed,  the  less 
labour  there  will  be  in  rubbing 
Brick  ffroinst  the  intersecting  or  meet- 
ing  of  two  circles  upon  their  dia- 
gonal elevations  drawn  upon  the 
different  sides  of  a  square,  whose 
principal  strength  Ues  in  the  united 
force  of  elevation  divided  by  geo- 
metrical proportions  to  one  certain 
gravity 
Bricklaying^  the  art  by  which  bricks 
ar6  joined  and  cemented,  so  as  to 
adhere  a  sone  body.    This  art,  in 
London,  includes  the  business  of 
walling,  tiling,    and  paving  vdth 
bricks  or  tiles 
Brick-nogging,  brick-work  carried  up 
and  fiUed  in  between  timber  fram- 
ing 
Brick  trimmery  a  brick  arch  abutting 
upon  the  wOoden  trimmer  under 
the  slab  of  a  fire-place,  to  prevent 
the  communication  of  fire 
Brick-trowelf  a  tool  used  for  taking  up 
mortar  and  spreading  it  on  the  top 
of  a  waU,  to  cement  together  the 
bricks,  &c. 
Bridge,  a  constructed  platform,  sup- 
ported at  intervals,  or  at  remote 
^  points,  for  the  purpose  of  a  road- 
way over  a  strait,  an  inlet  or  arm 
of  the  sea,  a  river,  or  other  stream 
of  water,  a  canal,  a  valley,  or  other 
depression,  or  over  another  road : 
it  is  distinguished  from  a  cause- 
way,  or  embanked  or  other  con- 
tinuously  supported  road-way,  and 
from  a  raft,  by  being  so  borne  at 
intervals    or    at    remote    points. 


63 


BRI 


BRIDGE. 


BRI 


Constructions  of  the  nature  and 
general  form  and  arrangement  of 
bridges, — such  as  aqueducts  and 
yiaducts ;  the  former,  being  to  lead 
or  carry  streams  of  ^ater  or  canals, 
and  the  latter,  to  carry  roads  or 
railways  upon  the  same,  or  nearly 
the  same  level,  oyer  depresBiouB,-=^ 
are  in  practice  considered  asbridges, 
although  they  are  not  such  in  the 
commonly  receiyed  sense  of  the 
term.  Taken,  however,  in  the 
sense  which  the  most  plausible  ety- 
mology that  has  been  suggested  of 
the  term  would  require,  the  word 
bridge  being  formed  by  prefixing 
the  constructive  be  to  ridget  a 
bridge  is  an  elevated  construction 
upon,  or  over  a  depression,  and  be- 
tween depressed  points. 

There  are  bridges  buQt  of  the 
materials,  stone,  brick,  iron,  timber, 
wire,  and  on  the  principles  of  sus- 
pension; for  the  explanation  of 
which,  see  the  word  Suspemion. 

The  bridge  across  the  Zab,  at 
Lizari,  is  of  basket-work.  Stakes 
are  firmly  fastened  together  with 
twigs,  forming  a  long  hurdle,  reach- 
ing from  one  side  of  the  river  to 
the  other.  The  two  ends  are  laid, 
upon  beams,  testing  upon  piers  on 
the  opposite  banks.  Both  the 
beams  and  the  basket-woric  are 
kept  in  their  places  by  heavy  stones 
heaped  upon  them.  Animals,  as 
well  as  men,  are  able  to  cross  over 
this  frail  structure,  which  swings 
to  and  fro,  and  seems  ready  to  give 
way  at  every  step.  These  bridges 
are  of  frequent  occurrence  in  the 
Tiejari  mountains. 
Bridges.  The  principal  object  to  be 
observed  in  forming  the  plan  of  a 
bridge,  is  to  give  a  suitable  afd 
convenient  aperture  to  the  arches, 
so  as  to  afford  a  free  vent  to  the 
waters  of  sudden  fioods  or  inunda- 
tions, and  to  secure  the  solidity  and 
duration  of  the  edifice  by  a  skilfril 
construction.  The  solidity  of  a 
bridge  depends  almost  entirely 
on  the  manner  in  which  its  foun- 
dations are  laid.    When  these  are 


64 


once  properly  arranged,  the  upper 
part  may  be  Greeted  either  with 
simplicity  or  elegance,  without  im- 
pairing in  any  degree  the  durability 
of  the  structure.  Experience  bas 
proved,  that  many  bridges  either 
decay,  or  are  swept  away  by  sud- 
den  floods,  by  reason  of  the  de- 
fective mode  of  fixing  their  founda- 
tions, while  very  few  suffer  from  an 
unskilfrd  construction  of  the  pilea 
or  arches.  This  hitter  defect,  how- 
ever, is  easy  of  correction,  nor  is  it 
difiicult  to  prevent  the  consequences 
that  might  be  expected  from  it. 

In  the  projection  of  a  bridge, 
five  principal  points  are  necessary 
to  be  considered, — ^first,  the  choice 
ofits  position  or  locality;  secondly, 
the  vent,  or  egress  that  must  be  al- 
lowed  to  the  river;  thirdly,  the 
form  of  the  arches;  fourthly,  the 
size  of  the  arches;  fifthly,  the 
breadth  of  the  bridge. 

Bridge-board^  or  notch-board,  a  board 
on  which  the  ends  of  the  steps  of 
wooden  stairs  are  fastened 

Bridged guitert  are  made  with  boards 
supported  by  bearers,  and  covered 
above  with  lead 

Bridgestonet  a  stone  laid  from  the 
pavement  to  the  entrance-door  of 
a  house,  over  a  sunk  area,  and  sup- 
ported  by  an  arch 

Bridging'/loorSf  floors  in  which  biidg- 
ing  joists  are  used 

Bridging-joiete  are  the  smallest  beams 
in  ndced  floorings,  for  supporting 
the  boarding  for  walking  upon 

Bridging-pieeeSf^ieceA  placed  between 
two  opposite  beams,  to  prevent 
their  nearer  approach,  as  rafters, 
braces,  struts,  &c. 

BrieOe,  the  spans  of  rope  attached  to 
the  leaches  of  square  sails,  to  which 
the  bow-lines  are  made  foil 

Bridle-cable,  in  navigation.  When 
a  vessel  is  moored  by  laying  down 
a  cable  upon  the  ground,  with  an 
anchor  at  each  end,  then  another 
cable  attached  to  the  middle  of  the 
ground  cable  is  called  bridle-cable 

Bridle-part,  the  foremost  part,  used 
for  stowing  the  anchors 


BRI 


BUCKETS. 


BUG 


Briff,  a  square-rigged  yesael  with  two 
masts 

Brtne-pun^,  the  pump  in  ■  ste^- 
ship,  used  occasionally  for  dnifdng 
off  a  sufficient  quantity  of  water)  to 
prevent  the  salt  from  depositing  in 
the  boiler 

BrittUnetB,  in  iron,  is  a  want  of  tena- 
city or  strength,  so  as  to  be  easily 
broken  by  pressure  or  impact: 
when  iron  is  made  too  hot,  so  as 
to  be  nearly  in  a  state  of  fiision, 
or  so  hard  as  to  resist  the  action 
of  the  file,  this  is  caUed  the  dispo- 
sition of  cast  iron 

Broach,  an  old  English  term  for  a 
spbe ;  still  in  use  in  some  parts  of 
the  country  todenote  a  spire  siNring- 
ing  from  the  tower  without  any 
intermediate  parapet 

Broaek-to,  to  fidl  off  so  much,  when 
going  free,  as  to  bring  the  wind 
round  on  the  other  quarter,  and 
tske  the  sails  a-back 

Broadride,  the  whole  side  of  a  vessel 

Broken  back,  the  state  of  a  vessel 
when  she  is  so  loosened  as  to  droop 
at  each  end 

Bromine,  in  chemistry,  is  found  com- 
bined with  silver  in  a  few  ores,  also 
m  sea-water  and  salt-springs ;  as 
bromide  of  potassium,  sodium,  or 
magnesium 

Broii<«ni,in  Greek  architecture,brazen 
vessels  placed  under  the  floor  of  a 
theatre,  with  stones  in  them,  to 
imitate  thunder 

Bronze,  a  compound  metal,  made  of 
from  6  to  12  parts  of  tin  and  100 
parts  of  copper 

Bnod,  in  noining,  any  heterogeneous 
mixture  among  tin  or  copper  ore, 
as  Mundick,  Black  Jack,  &c. 

Broumkiff,  a  process  by  which  the 
surfaces  of  articles  of  iron  acquire 
a  shining  brown  lustre :  the  mate- 
rial used  to  produce  this  is  the 
chloride  of  antimony 

Brown  ink.  Various  compounds  were 
used  in  sketching  by  Claude,  Rem- 
brandt, and  many  of  the  old  mas- 
ters, the  principal  of  which  were 
solutions  of  histre  and  sepia 
Broum  ochre,  S^^ruce  ochre,  or  Ochre 

65 


de  Rue,  a  kind  of  dark-coloured  yel- 
low ochre  :  it  is  much  employed,  and 
affords  useful  and  permanent  tints. 
This  and  all  natural  ochres  require 
grinding  and  washing  over,  to  se- 
parate them  from  extraneous,  sub- 
stances; and  they  acquire  depth 

'  and  redness  by  burning 

Brown-pink,  a  'flne  glazing  colour 
baring  but  little  strength  of  body. 
In  the  flesh,  it  should  never  join  or 
mix  with  the  lights,  because  this 
colour  and  white  antipathize  and 
mix  of  a  warm  dirty  hue ;  for  which 
reason  their  joinings  should  be 
blended  with  a  cold  middle  tint 

Brown-pott,  a  name  given  by  some 
builders  to  a  beam  laid  across  a 
building 

Brown  apar,  a  magnesian  carbonate 
of  lime,  tinged  by  oxide  of  iron  and 
manganese 

Bruiser,  a  concave  tool  used  in  grind- 
ing the  specula  of  telescopes 

Brunewick  green,  a  pigment  composed 
of  carbonate  of  copper  with  chalk 
or  lime 

Brush-wheeh  are  used  in  light  ma- 
chinery, to  turn  each  other  by 
means  of  bristles  or  brushes  fixed 
to  their  circumference 

Buata,  anciently  an  arch  or  chamber; 
a  crypt 

Bueca,  anciently  an  almonry 

Bucentcmr,  the  name  of  the  once  ce- 
lebrated galley  of  Venice,  used  by 
the  Doge  on  Ascension-day,  to  ce- 
lebrate the  wedding  of  the  Adriatic, 
by  dropping  a  ring  into  that  sea 

Suckers,  in  mining,  bruisers  of  the  ore 

Buckets,  in  water-wheels,  a  series 
of  carities  placed  on  the  circumfer- 
ence of  the  wheel,  and  into  which 
the  water  is  delivered,  to  set  the 
wheel  in  motion.  By  the  revolu- 
tion of  the  wheel  the  buckets  are 
alternately  placed  so  as  to  receive 
the  water,  and  inverted  so  as  to 
discharge  it;  the  loaded  side  al- 
vrays  descending 

Buckinff,  in  mining,  a  term  appBed  to 
a  method  of  breaking  the  poor  foul 
copper  ore  smaller  by  hand,  with 
smidl  flat  irons,  called  bucking. 


BUG 


BUILDIN9. 


BU 


ing-irons,  in  order  to  ^ash  and  se- 
parate the  pure  ore  from  the  use- 
less waste :  the  same  term  is  used 
in  the  lead-mines ;  but  Pettus,  in 
his  '  Plata  Miner/  gives  it  the  sig- 
nification of  washing  or  wet-stamp- 
ing  ores 

J3tfcit'ii^-troii,  in  mining,  the  tool  with 
which  the  ore  is  pulverized 

Buckle t  in  heraldry,  a  token  of  surety, 
fiedth,  and  service  in  the  bearer 

Buckler f  a  shield  of  armour,  anciently 
used  in  war 

BucklerBtin  ships,blocks  of  wood  made 
to  fit  in  the  hawse-holes,  or  holes 
in  the  half-ports,  when  at  sea 

Bucranett  in  sculpture,  the  heads  of 
oxeur  flayed  and  lacerated,  some- 
times represented  on  friezes 

Buddie f  in  mining,  a  pit  dug  in  the 
earth  near  the  stamping-mill,  7  feet 
long,  3  feet  wide,  and  2^  feet  deep, 
where  the  stamped  tin  is  curiously 
washed  from  its  impurities  by  water 
constantly  running  through  the  bud- 
die,  while  a  boy,  called  a  buddle- 
boy,  is  standing  in  the  body  of  it, 
and  working  both  with  a  shovel  and 
with  his  feet 

Budget,  a  pocket  used  by  tilers  for 
holdhig  the  nails  in  lathing  for  tiling 

Buffers^  in  locomotive  engines,  rods 
with  enlarged  ends  or  striking  blocks 
projecting  from  the  ends  ofthe  frame 
of  a  railway  carriage,  and  attached 
to  springs,  for  deadening  the  shocks 
received  from  the  engines 

BufUy  unbumished  gold 

Buhl-ifforkf  ornamental  furniture,  in 
which  tortoise-shell  is  inlaid  with 
wood  and  brass 

Builder,  a  term  applied  to  buildings  in 
civil  and  naval  architecture:  in  the 
former  he  is  mostly  employed  under 
the  superintendence  of  an  architect 
by  contract,  or  at  measure  and  value; 
the  latter,  under  the  naval  architect, 
mostly  by  contract 

Building,  thekart  which  comprises  all 
the  operayons  of  an  architect  in 
building  with  stone,  brick,  timber, 
iron,  cement,  &c. 

BuUdings.  Ofthe  aspects  best  adapted 
to  convenience  and  health,  for  the 

66 


different  kinds  of  buildings,  Vitru 
vius  writes :  **  The  principles  whicl 
should  be  attended  to  in  allotting 
to  each  kind  of  building  an  s^pro 
priate  aspect  remain  to  be  explain 
ed:  the  winter  eating-rooms  anc 
baths  ought  to  face  the  winter 
west,  because  the  use  of  them  re 
quires  that  they  should  be  li^ht  ai 
the  time  of  the  sun's  setting  :  be 
sides  which,  the  western  sun,  beinj 
immediately  opposite  to  them,  ren< 
ders  their  temperature  mild  at  the 
close  of  the  day.    The  sleeping 
apartments  and  libraries  should  be 
made  to  front  the  east,  because  the 
morning  hght  is  necessary  for  them 
and  books  are   better   preserved 
when  the  air  and  light  are  received 
from  that  quarter.    When  libraries 
have  a  southern  or  western  aspect, 
they  admit  those  winds,  which,  at 
the  same  time  that  they  carry  with 
them  moths,  instil  also  damp  va- 
pours into  the  books,  which,  in 
process  of  time,  cause  their  decay. 
The  vernal  and  autumnal  triclinia 
should  face  the  east,  because  the 
windows  being  turned  from  the 
sun's  rays,  whose  heat  increases  as 
the  sun  advances  towards  the  west, 
their  temperature  is  cool  at  the 
hours  they  are  generally  used.   The 
summer  tricliiua  should  front  the 
north ;  because,  having  that  aspect, 
they  will  be  least  exposed  to  the 
sun,  and  the  temperature  of  the 
apartments  will  be  grateful,  at  the 
same  time  that  it  is  conducive  to 
health.    No  other  aspect  possesses 
equal  advantages;  for  the  sun,  dur- 
ing the  solstice,  would  render  the 
air  of  all  others  sultry.    This  as- 
pect is  necessary  for  pinacothecae 
and  the  apartments  in  which  the 
pursuits  of  embroidery  and  painting 
are  followed,  because  the  colours 
used  in  works  of  this  kind  retain 
their  brightness  longer  when  ex- 
posed to  an  equable  and  regular 
Ught."— Wilkins's  Vit.  p.  220. 
BuUdingt  Act,  an  Act  of  Parliament 
^  passed  in  the  7th  and  8th  of  Vic- 
toria to  regulate  the  construction  of 


BUI 


BURDEN. 


BUR 


buildings  generally,  and  appurte- 
luuioea  thereto,  and  to  determine 
their  supervisions  by  district  sur- 
yeyors  and  referees 

BuUdmg  of  beams,  the  joining  of  two 
or  several  pieces  of  timber  together 
in  one  thickness,  and  of  several 
pieces  in  one  length,  by  means  of 
bolts,  so  as  to  form  a  beam  of  given 
dimensions,  which  it  would  be  im- 
possible to  obtain  from  a  single 
piece  of  timber 

Buleuteria,  among  the  Greeks,  coun- 
cil-chambers or  public  halls 

Bufye,  that  part  of  a  ship  which 
bulges  out  at  the  floor-heads,  to 
assist  the  ship  when  taking  the 
ground 

Buige'Wayt  ft  hurge  piece  of  timber,  or 
pieces  bolted  together,  making  one 
solid  piece,  placed  under  the  bulge 
of  a  diip,  to  support  her  launch. 
The  support  of  the  bulge-v^ays  to 
lie  on  is  called  ways,  which  some- 
times are'placed  straight  and  some- 
times cumber :  but  if  they  do  cum- 
ber, it  should  be  truly  circular; 
though  sometimes  the  curve  is 
quicker  at  the  lower  part,  but  this 
is  liable  to  strain  the  sheer  of  the 
ship.  Their  extreme  distance  is 
generally  about  one -third  the 
breadth  of  the  ship,  but  this  must 
depend  on  the  form  of  the  mid-ship 
bend 

Buiif  the  contents  of  the  hold  of  a  ship 

Bulk'headg,  partitions  built  up  in 
several  parts  of  a  ship,  to  form  and 
separate  the  various  apartments 

BnUantic,  so-called  ornamental  capital 
letters,  used  in  apostolic  bulls 

BuOm^iuUb,  such  as  have  round  heads 
with  short  shanks,  turned  and  lac- 
quered, used  principally  for  hang- 
ings  of  rooms 

BuHet  woodf  from  the  West  Indies,  is 
the  produce  of  a  large  tree  with  a 
white  sap ;  is  of  a  greenish  hazel, 
dose  hnd  hard;  used  in  the  coun- 
try for  building  purposes 

BuBet  woodf  another  species,  from 
Berbice,  is  of  a  hazel-brovm  colour, 
ad^>ted  to  general  and  eccentric 
turning 

~67 


BidTs-eye,  a  small  circularapertorefor 
the  admission  of  light  or  air 

Buffs-eye,  a  small  oval  block  of  hard 
wood  without  sheaves,  having  a 
groove  round  the  outside,  and  a 
hole  in  the  middle 

Bulwarks,  the  wood-work  round  a 
vessel,  above  her  deck,  consisting 
of  boards  fastened  to  stanchions 
and  timber-heads 

Bumboats,  those  which  He  alongside  a 
vessel  in  portwith  provisionsfor  sale 

Bumpkins,  pieces  fitted  above  the 
main -rail  in  the  head,  which  ex- 
tend nearly  as  far  forward  as  the 
fore-part  of  the  knee  of  the  head, 
and  are  for  the  use  of  hauling  down 
the  fore-tack 

Bunch,  or  Bunchy:  a  mine  that  is 
sometimes  rich  and  at  other  times 
poor,  is  said  to  be  bunchy 

Bunch,  or  Squat,  in  mining,  a  quan- 
tity of  ore,  of  small  extent,  more 
than  a  stone  and  not  so  much  as  a 
course :  a  mine  is  said  to  be  bunchy 
when  these  are  found  in  place  of  a 
regular  lode 

Bundle-pillar,  a  column  or  pier,  with 
others  of  small  dimensions  attached 
to  it 

Bunny,  in  mining,  of  tin  or  copper 
ore ;  a  sombrero  in  Alonzo  Barba ; 
a  pipe  of  ore ;  a  great  collection 
of  ore  without  any  vein  coming  into 
or  going  out  from  it 

Bunt  of  a  sail,  the  middle  part  formed 
into  a  bag  or  cavity,  that  it  may 
gather  more  wind 

Buntine,  thin  woollen  stuff,  of  which 
a  ship's  colours  are  made 

Bunt-line  cloth,  the  Uning  sewed  up 
the  sail  in  the  direction  of  the 
bunt-Une,  to  prevent  the  rope  from 
chafing  the  sail 

Bunt-lines,  ropes  fastened  to  cringles 
on  the  bottoms  of  the  square  sails, 
to  draw  them  up  to  their  yards 

Buoy,  a  cask,  or  block  of  wood,  fast- 
ened by  a  rope  to  an  anchor,  to 
point  out  sho^  or  particular  spots . 

Burden,  in  mining,  the  tops  or  heads 
of  stream-work  which  lie  over  the 
stream  of  tin,  and  which  must  be 
first  cleansed 


BUR 


BURNERS. 


BUR 


Bwrdon^  a  pilgrim's  staff 

Bureau^  a  chamber  or  office  for  the 
transaction  o£  state  or  business  af- 
fairs 

Burge»,  the  Persian  word  for  Towers, 
evidently  the  same  as  the  Gothic 
burgh;  a  fortified  dwelling  or  en- 
closed town.  Cfird  or  geard  is  in 
Persian  a  city  or  fortress,  which 
approximates  togarthf  an  enclosure, 
in  the  Gothic :  hence  garden.  But 
a  castle,  comprehending  towers  and 
walls,  is  in  Persian  calaa 

Burgundy  pitch,  a  resin  collected 
from  the  spruce  fir 

Burguif  anciently  a  number  of  houses 
protected  by  a  fortress 

Burgward,  anciently  the  custody  or 
keeping  of  a  castle 

Burg-work,  anciently  applied  to  a 
castle  or  borough 

Burm,  an  engrayer's  instrument;  a 
graver 

Burners,  for  gas-light.  Coal-gas  has 
now  been  used  for  the  purposes  of 
artificial  illumination  nearly  fifty 
years,  and  the  burners  sanctioned 
by  the  companies  at  the  present 
day  are  of  several  shapes. 

Carburetted  hydrogen  of  the  spe- 
cific gravity  '390  (which  is  about 
the  density  of  gas  when  arrived  at 
the  point  where  it  has  to  be  burnt) 
requires  two  volumes  of  pure  oxy- 
gen for  its  complete  combustion  and 
conversion  into  carbonic  acid  and 
water.    Atmospheric  air  contains, 
in  its  pure  state,  twenty  per  cent, 
of  oxygen,  —  in  populous  tovms 
less ;  but  twenty  per  cent,  may  be 
taken  as  a  fiiir  average:  1  cubic 
foot  of  carburetted  hydrogen  then 
requires  for  its  proper  combustion 
10  cubic  feet  of  air;  if  less  be  ad- 
mitted  on  to  the  fiame,  a  quantity 
of  free  carbon  will  escape  (from  its 
not  finding  a  proper  volume  of  oxy. 
gen  for  conversion  into   carbonic 
acid),  and  be  deposited  in  ^^  form 
of  dense  black  smoke.    When  the 
fiame  frt>in  an  Argand  burner  is 
turned  up  high,  the  air  which  rushes 
through  the  interior  ring  becomes 
decomposed  before  it  can  reach  the 

68 


air  on  the  top  of  the  fiame,  which 
consequently  bumsin  one  undivided 
mass,  the  gas  being  in  part  uncon- 
sumed,  the  products  nnconyerted, 
and  carbon  deposited  abundantly. 

If  an  excess  of  air  is  admitted,  it 
would  appear  at  first  to  be  of  no 
consequence,  but  it  will  be  found 
that  the  quantity  of  nitrog^  ac> 
companying  this  excess  has  a  ten- 
dency to  extinguish  the  fiame,  while 
it  takes  no  part  in  the  elective  affi- 
nity constantly  going  on  between 
the  several  elementary  gases,  viz. 
hydrogen,  oxygen,  and  the  vaponr 
of  car&n;  and  also  thatthe  qnantity 
of  atmospheric  air  passing  through 
the  flame  unchanged,  tends  to  re- 
duce the  temperature  below  that 
necessary  for  ignition,  and  therefore 
to  diminish  the  quantity  of  light. 
For  the  proper  combustion  of  the 
gas,  neither  more  nor  less  air  than 
the  exact  quantity  required  for  the 
formation  of  carbonic  add  and  water 
can  be  admitted  through  the  flame 
without  being  injurious.  It  is  not 
possible  practically  to  regulate  the 
supply  of  air  to  such  a  nicety:  it  is 
preferred  therefore  to  diminish  the 
quantity  of  light  by  having  a  slight 
excess  of  air  rather  than  to  pro- 
duce smoke  by  a  deficiency,  the 
former  being  unquestionably  the 
least  evil. 

Bummg-gkue,  a  ghiss  lens,  which, 
being  exposed  directiy  to  the  son, 
refracts  the  rays  which  £all  upon  it 
into  a  focus 

Burning-house,  the  furnace  in  which 
tin  ores  are  calcined,  to  sublime  the 
sulphur  frx)m  pyrites:  the  latter 
being  thuv  decomposed,  are  more 
readily  removed  by  washing 

Burnisher,  a  tool  used  for  smoothing 
and  polishing  a  rough  smrfa<*e. 
Agates,  polished  steel,  ivory,  &:c., 
are  used  for  burnishing 

Burnt  Carmine  is,  according  to  its 
name,  the  carmine  of  cochineal  par- 
tially charred  till  it  resembles  in 
colour  the  purple  of  gold,  for  the 
uses  of  wldch  in  miniature  and 
water  piunting  it  excels 


BUR 


BUTTRESS. 


BT 


Bumi  Sienna  earth  is,  as  its  name 
impiiest  the  terra  di  sienna  bamt, 
snd  is  of  an  orange-nisset  colour 

Burnt  Umber y  apigment  obtained  from 
a  fossil  substance,  which  when  burnt 
sssumes  a  deeper  and  more  russet 
hue :  it  contains  manganese  and 
iron,  and  is  very  drying  in  oil,  in 
which  it  is  employed  as  a  diyer. 
It  is  a  fine  warm  brown,  and  a  good 
working  strong  colour,  of  great  use 
iat  the  hair  of  the  human  head,  and 
mixes  finely  with  the  warm  shade 

Bmmt  Verdigri».i%  an  olive-coloured 
oxide  of  copper  deprived  of  add. 
It  dries  weU  in  oil,  and  is  more 
durable,  and  in  other  respects  an 
improved  and  more  eligible  pig- 
ment than  in  its  original  state 

Btar/'etone,  a  mill-stone  which  is  al- 
most pure  silex :  the  best  kind  is 
of  a  whitish  colonr 

Burrock,  a  small  weir  or  dam,  where 
wheels  are  laid  in  a  river  for  catch- 
ing fish 

BumtWf  in  mining,  the  heap  or  heaps 
of  attle,  deads,  or  earth  (void  of 
ore),  which  are  raised  out  of  a  mine, 
and  commonly  lie  around  the  shafts ; 
sny  heap  or  hiUock  of  deads  or 
waste 

Bmr-fmn^,  a  bilge-pump  worked  by 
a  bar  of  wood  pulled  up  and  down 
by  a  rope  fastened  by  the  middle 

Buna,  a  bag;  a  purse  used  in  the  mid- 
die  ages  for  the  purposes  of  a  little 
college  or  hall  for  students 

Btartar,  one  to  whom  a  stipend  is 
paid  out  of  a  fund  set  apart  for  poor 
students;  the  treasurer  of  a  college 

Bunary,  the  treasury  of  a  college 

Bunery,  the  exchequer  of  collegiate 
and  conventual  houses,  and  for 
paying  and  receiving  monies 

Burthenj  the  weight  or  measure  of 
capacity  of  a  ship.  Multiply  the 
length  of  the  keel,  the  inner  mid- 
ship breadth,  and  the  depth  from 
the  main-deck  to  the  plank  joining 
the  keelson  together ;  and  the  pro- 
duct, divided  by  94,  gives  the  ton- 
nage or  burthen 

Burton,  a  manor ;  a  manor-house 

Burton,  in  a  ship,  a  small  tackle  of 

""I9  "  ~ 


two  single  blocks,  named  from  the 

inventor 
Bush,  in  machinery,  a  piece  of  metal 

fitted  into  the  plummer-block  of  a 

shaft  in  which  the  journal  turns. 

The  guide  of  a  sliding-rod  also 

bears  the  same  name 
Bush,  a  circular  piece  of  iron  or  other 

metal,  let  into  the  sheaves  of  such 

blocks  as  have  iron  pins,  to  prevent 

their  wearing 
Bushel,  a  dry  measure  of  8  gallons  or 

4  pecks 
Bush-harrow,  an  implement  used  in 

harrowing  grass  lands 
Bushm,  a  high  shoe  or  boot  worn  an- 
ciently, in  tragedy,  on  the  stage 
Buss,  a  small  sea-Tcaael  used  in  the 

herring-fisheiy 
Bust,  in  sculpture,  the  head,  neck, 

and  breast  of  a  human  figure 
Bustum,  anciently  a  tomb 
But,  the  end  of  a  plank  where  it 

unites  with  another 
But'hmges,  those  employed  in  the 

hanging  of  doors,  shutters,  &c 
Butmen  cheeks,  the  two  solid  sides  of 

a  mortise  varying  in  thickness 
Butments,  the  supports  on  which  the 

feet  of  arches  stand 
Butterffy'Vahfe,  the  double  valve  of 

an  air-pump  bucket,  consisting  of 

two  clack-valves,  having  the  joints 

opposite  and  on  each  side  of  the 

pump-rod 
Butteris,  an  instrument  of  steel  set 

in  a  wooden  handle,  used  by  far- 

riers  for  paring  the  hoof  of  a  horse 
Buttery,  a  cellar  in  which  butts  of 

wine  are  kept;  a  place  for  provisions 
Buttock,  the  round  part  of  a  ship 

abaft,  frx)m  the  wing  transom  to  the 

upper  water-line,  or  lower  down 
Buttres8,inGothie  architectural  struc- 
tures, a  pilaster,  pier,  or  masonry 

added  to  and  standing  out  from  the 

exterior  of  a  wall 
Buttress,  a  piece  of  strong  wall  that 

stands  on  the  outside  of  another 

wall,  to  support  it 
By,  said  of  a  vessel  when  her  head  ia 

lower  in  the  water  than  her  stem ; 

if  her  stem  is  lower  in  the  water. 

she  is  by  the  stem 


BYA 


BYZANTINE  ARCHITECTURE. 


BYZ 


Byard,  a  piece  of  leather  across  the 
breast,  used  by  those  who  drag  the 
sledges  in  coal-pits 
Byzantine  Architecture,  About  the 
year  a.d.  328,  Constantine,  who 
had  previously  resided  at  Rome, 
commenced  his  new  capital  in  the 
East,  which  was  called  after  his 
name,  and  in  May,  330,  was  so- 
lenmly  dedicated  to  the  Virgin 
Mary.  He  adorned  it  with  so 
many  stately  edifices  that  it  nearly 
equalled  the  ancient  capital  itself: 
he  here  built  a  cathedral  dedicated 
to  Santa  Sophia  or  the  Eternal  Wis- 
dom, and  a  church  to  the  Apostles. 
This  cathedral,  having  been  twice 
destroyed  by  fire,  was  finally  rebuilt 
about  532  a.  d.,  by  Justinian,  who 
had  invited  the  celebrated  architect 
Anthemius  to  Constantinople  for 
that  purpose.  It  was  completed  in 
six  years  from  the  time  of  laying 
the  first  stone. 

The  emperor,  in  his  admiration 
of  this  magnificent  edifice,  is  said  to 
have  exclaimed,  '^  I  have  vanquished 
thee,  O  Solomon  :*'  and  with  justice 
might  he  glorify  himself;  for  the 
dome  of  St.  Sophia  is  the  largest  in 
the  world,  and  the  more  to  be  ad- 
mired in  its  construction  from  the 
lowness  of  the  curvature. 

This  church,  after  twelve  centu- 
ries, remains  the  same,  vnth  the  ex- 
ception of  the  mode  of  worship  to 
which  it  is  devoted.  It  stiU  retains 
its  former  name,  but  the  Mahome- 
tans, instead  of  the  Christiims,  pos- 
sess  it. 

This  is  the  earliest  Byzantine 
building  extant,  totally  dissimilar 
in  arrangement  to  the  Christian 
churches  in  the  empire. 

The  plan  of  the  interior  is  that  of 
a  Greek  cross,  the  four  arms  of 
which  are  of  equal  length ;  the  cen- 


tral part  is  square,  the  sides  are 
about  115  feet  in  length.  At  eacli 
angle  of  the  square  a  ^massive  pier 
has  been  carried,  86  feet  in  height 
from  the  pavement,  and  four  semi- 
circular  arches  stretch  across  the 
intervals  overthe  sides  ofthe  square, 
and  rest  on  the  piers.  The  iDterior 
angles  between  the  four  piers  are 
filled  up  in  a  concave  form.  At 
145  feet  from  the  ground  is  the  level 
ofthe  springing  ofthe  dome,  which 
is  115  feet  in  ^Sameter ;  the  form  is 
a  segment  of  a  circle,  and  the  height 
is  equal  to  one-sixth  of  its  diameter 
at  the  base.  On  both  the  eastern 
and  western  side  of  the  square  is  a 
semicircular  recess,  with,  domes  that 
rest  against  the  main  arches,  and 
assist  in  resisting  the  lateral  thmst. 
On  the  north  and  south  sides  of  the 
square  are  vestibules  forming^  a 
square  on  the  plan.  Aboye  the  vesti- 
bules are  galleries  appropriated  to 
women  during  the  p^ormanoe  of 
worship.  The  whole  church  is  smr- 
rounded  by  cloisters,  and  enclosed 
by  walls. 

The  total  cost  of  St.  Sophia  has 
been  reckoned  at  the  lowest  com. 
putation  to  have  exceeded  one  mil. 
lion  pounds ;  as  before  the  building 
was  4  feet  out  of  the  ground,  its 
cost  had  amounted  to  a  sum  eqni. 
valent  to  £  200,000  sterling. 

Besides  this  cathedral,  Justdnian 
is  said  to  have  built,  at  Constant!. 
nople,  twenty.five  churches  to  the 
honour  of*  Christ,  the  Virg^,  and 
'  the  Saints ;  he  also  built  a  church. 
to  St.  John  at  Ephesus,  and  another 
to  the  Virgin  at  Jerusalem  7  the 
bridges,  hospitals,  and  aqnedocts 
erected  by  this  emperor  were  nu- 
merously distributedthroughoutthe 
empire. 
Byzanteum  artificiumf  Mosaic-'work 


CAB 

Cabbling.  The  proctss  in  the  ma- 
nufiicture  of  iron,  which  in  Glou- 
cestershire is  called  *  scabbling,'  or, 

70 


CAB 

more  correctly,  <  cabbling,'  may  be 
thus  described.  When  tiie  cast  or 
pig  iron  has  been  subjected  to  the 


CAB 


CALCULATING  MACHINE. 


CAI 


influence  of  a  refinery,  the  product  is 
called  *  Finery:'  it  is  then  carried  to 
the  forge,  jand  smelted  in  a  furnace 
with  charcoal :  in  a  short  time,  a 
large  hall,  about  2i  cwt.,  is  formed 
by  working  with  an  iron  har ;  this 
ball  is  then  taken  to  a  large  ham- 
mer,  and  beaten  into  a  flat  oval  or 
oblong  shape,  from  2  to  4  inches 
in  thickness:  this  is  allowed  to 
cool,  when  '  cabbling'  commences, 
and  which  is  simply  breaking  up 
this  fiat  iron  into  small  pieces. 
Men  are  especially  allocated  for 
this  operation,  and  are  named 
*  cahblers/  The  pieces  of  iron  ob- 
tained by  cabbling  are  then  heated 
in  another  furnace  almost  to  fusion, 
hammered  down  into  shape,  and 
ultimately  drawn  out  into  bar-iron 

Ca^  a  room  or  apartment  in  a  ship 
^here  any  of  the  ofiScers  usually 
reside,  and  also  used  in  passenger 
vessels  for  the  residence  of  passen- 
gers 

(Mtet  pictures,  usually  denominated 
80,  are  small  valuable  paintings  from 
the  old  masters,  painted  on  copper, 
panel,  or  canvas.  Modem  subjects, 
if  painted  small  in  size,  should 
equally  be  called  Cabinet 

Cabinets,  in  Tudor  times,  were  of 
maissive  proportions,  carved  in  oak, 
ebony,  walnut,  and  other  woods, 
inlaid.  Some  of  them  answered 
the  double  purpose  of  depositories 
&nd  cupboards  for  plate,  from 
baring  drawers  and  recesses,  or 
unbries,  enclosed  by  doors;  and 
broad  shelves  between  the  tiers  of 
turned  columns  were  conspicuous 
objects  in  these  apartments 

Cable,  a  thick  stout  rope,  made  of 
hemp,  &c.,  to  keep  a  ship  at  anchor 

Cable-mouldingj  ahead  ortorus  mould- 
ing, cut  in  imitation  of  the  twisting 
of  a  rope,  much  used  in  the  later 
period  of  the  Norman  style 
Cab^ng^  a  round  moulding,  frequently 
used  in  the  fiutes  of  columns,  pilas- 
ters,  &c. 
^^«*««<rtw,  an  emblem  or  attribute  of 
Mercury ;  a  rod  entwined  by  two 
^ged  serpents 

1\ 


Calatura  (Greek),  a  branch  of  th< 
fine  arts,  under  which  all  sorts  <x 
ornamental  work  in  metal,  ezoepil 
actual  statues,  appear  to  be  indudeid 

C€Bmentieius,  bi^t  of  unhewn  stones ; 
large  irregular  masses  laid  togetha 
without  mortar,  having  the  inter« 
stices  filled  in  with  smiUl  chipping! 

Caen  stone,  a  peculiar  quality  of  stone 
used  for  building  purposes,  prin- 
cipally for  Gothic  structures ;  it  ii 
taken  fit>m  quarries  in  Normandy 

Caisson,  a  wooden  frame  or  box  with 
a  flat  bottom,  made  of  strong  timben 
firmly  connected  together;  used  for 
laying  the  foundations  of  a  bridge 
in  situations  where  the  oofibr-dam 
cannot  be  adopted 

Caisson,  a  name  given  to  the  sunk 
panels  of  various  geometrical  forms 
symmetrically  disposed  in  flat  or 
vaulted  ceilings,  or  in  soffits  gene- 
rally 

Cal,  in  Cornish  mining,  a  kind  of  iron 
Gossan  stone  found  in  the  bryle  and 
backs  of  lodes,  much  of  the  colour 
of  old  iron ;  reckoned  a  poor  brood 
with  tin 

Calcar,  a  small  oven  or  reverberatory 
furnace,  in  which  the  first  calcina- 
tion of  sand  and  potashes  is  made 
for  turning  them  into  frit,  firom 
which  glass  is  ultimately  made 

Calcareous  earth,  the  same  as  lime, 
and  of  which  there  are  various  com- 
binations, as  marble,  limestone, 
marl,  gypsum,  &c. 

Caleatonum,  among  the  Romans,  a 
raised  'platform  of  masonry  in  the 
cellar  attached  to  a  vineyard 

Calcination,  the  process  of  subjecting 
a  body  to  the  action  of  fire,  to  drive 
off  the  volatile  parts,  whereby  it  is 
reduced  to  a  condition  that  it  may 
be  converted  into  a  powder :  thus 
marble  is  converted  into  lime  by 
driving  off  the  carbonic  add  and 
water;  and  gypsum,  alum,  borax, 
and  other  saUne  bodies  are  said  to 
be  calcined  when  they  are  deprived 
of  theur  water  of  crystallization 

Calcium,  the  metallic  basis  of  lime 

Calcography,  to  write,  engrave,  &c. 

Calculating  machmes  are  of  early  in- 


CAL 


CAMBER  SLIP. 


CAM 


Tention ;  but  recently  Mr.  Babbage 
has  completed  a  cidculating  ma- 
chine surpassing  all  previous  ones : 
the  machine  accomplishes  the  ad- 
ditions of  numbers  by  the  move- 
ments of  a  number  of  cylinders 
having  on  the  convex  surface  of 
each  the  series  of  numbers  12  3  4 
5  6  7  8  9  0;  and  the  operations 
are  of  two  Idnds :  by  the  first  the 
additions  are  made,  and  by  the 
second  there  is  introduced  the  l, 
which  should  be  carried  to  the 
ten's  place  every  time  that  the  sum 
of  the  two  numbers  is  greater  than 
10,  &c. 

Caldariumt  the  hot  bath.  The  vase 
which  supplied  the  hot  bath  was 
likewise  so  termed  • 

Caldariumf  according  to  Vitruvius,  the 
thermal  chamber  in  a  set  of  baths 

CalendcTf  a  mechanical  engine  for 
dressing  and  finishing  cloths 

Calends,  in  Roman  antiquity,  the  first 
day  of  every  month 

Caliber  or  Caliper  compasses;  com- 
passes made  virith  bowed  or  arched 
legs,  for  the  purpose  of  taking  the 
diameter  of  any  round  body 

Caliber,  an  instrument  used  by  car- 
penters, joiners,  and  bricklayers,  to 
see  whether  their  work  be  well 
squared 

CaUco,  a  doth  made  from  cotton  wool, 
like  linens ;  the  origin  of  the  name 
is  from  Calicut,  in  India 

Caiico  printing,  the  art  of  applying 
coloured  patterns  on  a  white  or 
coloured  ground  of  linen  or  cotton 

Calk,  a  Cornish  term  for  lime 

Calipers,  a  species  of  compasses  with 
legs  of  a  circular  form,  used  to  take 
the  thickness  or  diameter  of  work, 
either  circular  or  flat;  used  also  to 
take  the  interior  size  of  holes 

CdUipers,  in  turning,  compasses  with 
each  of  the  legs  bent  into  the  form 
of  a  curve,  so  that  when  shut  the 
points  are  united ;  and  the  curves, 
being  equal  and  opposite,  enclose  a 
space.  The  use  of  the  callipers  is 
to  try  the  work  in  the  act  of  turn- 
ing, in  order  to  ascertain  the  dia- 
meter orthe  diameters  of  the  various 


parts.  As  the  points  stand  nearer 
together  at  th^  greatest  required 
diameter  than  the  parts  of  the  legs 
above,  the  caUipers  are  well  adapted 
to  the  use  intended 

CaUys  or  KUlas  (Cornish),  hard,  smart; 
the  most  common  and  agreeable 
stratum  in  our  mine  country,  usually 
called  killas 

Calorie,  the  matter  and  cause  of  heat 

Caloric,  in  chemistry,  the  quality  of 
producing  heat 

Calorimeter,  an  instrument  to  measure 
the  heat  given  out  by  a  body  in 
cooling  by  the  quantity  of  ice  it  melts 

Cdtquing,  the  process  of  copying  or 
tran^eiring  a  drawing.  It  is  ef- 
fected by  rubbing  over  the  back  of 
the  original  with  a  fine  powder  of 
red  chalk  or  black  lead;  the  smeared 
side  is  then  laid  on  a  sheet  of  paper, 

and  thelinesofthedrawingare  traced 
by  a  blunt-pointed  needle,  which 
imprints  them  on  the  paper  under- 
neath. Another  method  is  to  hold 
the  drawing  up  to  a  vrindow  with 
a  sheet  of  paper  before  it:  the  out- 
lines  will  appear  through,  and  may 
be  pencilled  off  without  damage  to 
the  original 

Calyon,  flint  or  pebble  stone,  used  in 
building  walls,  &c. 

Cam,  in  steam  machinery,  a  plate  with 
curved  sides,  triangular  or  other- 
vrise,  fixed  upon  a  revolving  shaft, 
for  changing  the  uniform  rotatory 
motion  into  an  irregular  rectilineal 
motion.  It  is  sometimes  used  for 
moving  the  slide-valves 

Camaieu,  a  term  used  ib  painting  when 
there  is  only  one  colour,  the  light 
and  shades  being  of  goldf  or  on  a 
golden  andazureground.  Itis  chiefly 
used  to  represent  basso-rilievo 

Camber,  the  convexity  of  a  beam  upon 
the  upper  surface,  in  order  that  it 
may  not  become  concave  by  its  own 
weight,  or  by  the  tinder  it  may  have 
to  sustain,  in  the  course  of  time 

Camber-beams  are  those  used  in  the 
flats  of  truncated  roofs,  and  raised 
in  the  middle  with  an  obtuse  angle 
for  discharging  the  rain-water  to- 
virards  both  sides  of  the  roof 


72 


CAM 


CANAL. 


CAN 


Camber-si^,  a  piece  of  wood,  ^ne- 
rally  about  half  an  inch  thidc,  with 
at  least   one    curved  edge  rising 
aboat  1  inch  in  6  feet,  £91  drawing 
the  soffit-lines  of  straight  arches : 
when  the  other  edge  is  curved,  it 
rises  only  to  about  one-half  of  the 
other,  viz.  about  half  an  inch  in 
6  feet,  for  the  purpose  of  drawing 
the  upper  side  of  the  arch  so  as 
to  prevent  it  from  becoming  hol- 
low by  the  settling  of  the  bricks. 
The  upper  edge  of  the  arch  is  not 
always  cambered,  some  persons  pre- 
ferring it  to  be  straight.   The  brick- 
layer is   always   provided  with  a 
camber-slip,  which  being  sufficiently 
long,  answers    to   many  different 
widths  of  openings :  when  he  has 
done  drawing  his  arch,  he  gives 
the  camber-slip  to  the  carpenter, 
in  order  to  form  the  centre  to  the 
required  curve  of  the  soffit 

Cambering  J  a  sea  phrase,  used  when  a 
deck  is  higher  in  the  middle  than 
at  the  ends 

Camel,  the  name  of  a  machine  used  by 
the  Dutch  for  carrying  vessels  hea- 
vily laden  over  the  sand-banks  in 
the  Zuyder  Zee 

Camera  (Greek),  an  arched  or  vaulted 
roof,  covering  or  ceiling,  formed  by 
circular  bands  or  beams  of  wood, 
over  the  intervals  of  which  a  coating 
of  lath  and  plaster  was  spread: 
they  resembled,  in  their  construc- 
tion, the  hooped  awnings  now 
commonly  in  use 

Camera-lucidaf  and  Camera-ohtcura, 
(the  light  and  dark  chamber,)  the 
names  given  to  two  methods,  simi- 
lar in  principle,  of  throwing  images 
of  external  objects  upon  plane  or 
curved  surfaces,  for  the  purpose  of 
drawing  or  amusement:  in  the  first 
contrivance  there  is  no  chamber; 
but  as  it  was  the  last  invented,  and 
as  its  predecessor  had  been  called 
the  *camera-obscura,'  it  was  termed 
the  'camera-lucida' 

Camerated,  a  term  applied  to  the  roof 
of  a  church 

Camegf  the  slender  rods  of  metal 
used  by  glaziers  as  turned  lead; 

73  " 


th^  are  usually  cast  in  lengths 
which  measure  12  or  14  inches 
Caminus,  according  to  Pliny,  a  smelt- 
ing furnace 
Canyfarue  or  CampamUaf  or  GutttB, 

the  drops  of  the  Doric  architrave 
Campanile,  from  the  Italian,  a  bell- 
tower,  principally  used  for  church 
purposes,  but  now  sometimes  for 
domestic  edifices 
Camphor  wood  is  imported  from  China 
and  the  Indies  in  logs  and  planks 
of  large  size,  and  used  in  Enghmd 
for  cabinet-work  and  turnery 
Canqnti  Marthu,  a  district  outside 
the  walls  of  ancient  Roine,  between 
the  Quirinal  and  Pindan  Mounts 
and  the  Tiber,  dedicated  to  Mars : 
there  public  exerdsss  were  per- 
formed, and  the  consuls  and  other 
magistrates  elected :  it  was  adorned 
with  statues,  columns,  arches,  &c., 
and  much  frequented  by  the  citizens 
Cam  wood,  the  best  and  hardest  of 
the  red  dye-woods:  it  is  brought 
from  Africa,  and  used  in  ornamental 
and  eccentric  turnery 
Canal,  an  artificial  water-course  for 
connecting  rivers  or  lakes ;  a  navi- 
gable communication 
Canalia,  in  Latin,  a  water-pipe  or 
gutter ;  used  in  architecture  for  any 
channel,  such  as  the  flutings  of  co- 
lumns; the  channel  between  the 
volutes  of  an  Ionic  column 
Canary  wood,  from  South  America, 
is  a  sound,  light,  orange-coloured 
wood,  used  for  cabinet-work,  mus- 
ketry, and  turnery 
CanceUi,  among  the  Romans,  iron 
gratings  and  trellis-work  ;  in  mo- 
dem buildings,  latticed  vrindows 
made  with  cross-bars  of  wood,  iron, 
lead,  &c 
Candela,  a  candle,  made  either  of 
wax  or  tallow ;  used  generally  by 
the  Romans  before  the  invention 
of  lamps 
Candelabrum,   originally    a    candle- 
stick, but  afterwards  used  to  sup. 
port  lamps 
Candlemas,  the  popular  name  for  the 
feast    of  the   Purification   of  the 
Virgin  Mary,  February  2,  derived 


CAN 


CAOUTCHOUC. 


CAO 


from  the  lights  which  were  then 
distrihuted  and  carried  about  in 
procession 

Candlestick  of  gold  {The)  was  made 
by  Moses  for  the  service  of  the 
Temple,  and  consisted  wholly  of 
pure  gold :  it  had  seyen  brandies, 
upon  the  extremities  of  which  were 
seven  golden  lamps,  which  were 
fed  with  pure  olive  oil,  and  lighted 
every  evening  by  the  priest  on 
duty  :  it  was  used  in  the  holy 
place,  and  served  to  illumine  the 
altar  of  incense  and  the  table  of 
shew-bread,  which  stood  in  the 
same  chamber 

Candleeticks,  The  magnificence  of 
these  articles  was  at  fot  displayed 
in  chapels  and  in  domestic  apart- 
ments, as  banquets  in  early  times 
were  given  by  daylight.  We  find 
them,  however,  of  very  costly  de- 
scriptions. In  Henry  the  Eighth's 
temporary  banqueting -room,  at 
Greenwich,  "the  candlestykes  were 
of  antyke  worke,  whichoare  little 
torchetts  of  white  waxe:  these 
candlestykes  were  polished  lyke 
ambre." 

Cangica  wood,  from  South  America,  is 
of  a  light  and  yellow-brown  colour, 
used  for  cabinet-work  and  turnery 

Can-hookSt  strings  with  flat  hooks  at 
each  end,  used  for  hoisting  bar- 
rels or  light  casks 

Canopy f  a  covering  or  hood,  the  en- 
riched projecting  head  to  a  nichie 
or  tabernacle.  The  tablet  or  drip- 
stone, whether  straight  or  circular, 
over  the  heads  of  doors  or  windows, 
if  enriched,  is  so  called 

Canopy,  in  Gothic  architecture,  an 
ornamental  projection  over  doors, 
windows,  &c.;  acoveringover  niches, 
tombs,  &c. 

Cant,  a  term  used  among  carpenters 
to  express  the  cutting  off  the  angle 
of  a  square 

CantaUver,  a  kind  of  bracket  to  sup- 
port eaves,  cornices,  balconies,  &c. 

Canted,  applied  to  a  pillar  or  turret 
when  the  plan  is  of  a  polygonal 
form 

Canterii,  beams  of  wood  in  the  frame- 


work  of  a  roof,  extending  from  the 
ridge  to  the  eaves,  corresponding 
to  the  rafters  of  a  modem  roof. 
The  word  canterii  was  also  applied 
to  two  inclining  reeds  fixed  in  the 
ground  some  distance  asunder  and 
meeting  at  the  top,  for  the  support 
of  vines 

Canthartu,  a  fountain  or  cistern  in 
the  atiium  or  court-yard  before 
ancient  churches,  at  which  persons 
washed  before  they  entered  the 
sacred  buildings 

Canthu,  in  Greek  and  Latin,  the 
tire  of  a  wheel;  a  hoop  of  iron  or 
bronze  fastened  on  to  the  felloe,  to 
preserve  the  wood  from  abrasion 

Cantilevert  are  horizontal  rows  of 
timbers,  projecting  at  right  angles 
from  the  naked  part  of  a  wall,  for 
sustaining  the  eaves  or  other  mould- 
ings 

Cant-moulding,  abevelled  surface,  nei- 
ther perpendicular  to  the  horizon 
nor  to  the  vertical  surface  to  which 
it  may  be  attached 

Cantoned,  in  architecture,  is  when  the 
comer  of  a  building  is  adorned 
with  a  pilaster,  an  angular  column, 
rustic  quoins,  or  any  thing  that  pro- 
jects beyond  the  wall 

Cani'piecee,  in  ships,  pieces  of  timber 
fastened  to  the  angles  of  fishes  and 
side-trees,  to  supply  any  part  that 
may  prove  rotten 

Cant'timbere,  in  ship-building,  those 
timbers  or  ribs  of  the  ship  which 
are  situated  afore  or  abaft,  or  at  the 
two  ends,  where  the  ship  grows 
narrower  below 

Cant'timber  abaft,  the  chock  upon 
which  the  spai^er-boom  rests  when 
the  sail  is  not  set 

Caniuar,  The  signature  of  the  Arch- 
bishop  of  Canterbury,  is  thus  abbre- 
viated, the  Christian  name  being 
usually  prefixed 

Canvas,  the  cloth*  of  which  the  sails 
of  ships  are  made 

Caoutchouc,  a  substance  produced  by 
the  sephonia  elastica,  the  ficus  elas- 
tica,  and  the  urceola  elastica,  and 
many  other  American  and  Asiatic 
trees.     It  is  often  termed  Indian 


CAP 


CAPITOL. 


CAl 


T 


rubber,  from  its  use  in  removing 
pencil  traces  from  paper.  There  are 
various  chemical  properties  which 
render  caoutchouc  viduable  in  the 
arts,  but  elasticity  and  iropervious- 
ness  to  water  are  those  for  which 
it  is  most  prized.  It  is  worked  into 
a  great  variety  of  useful  things  for 
dms  and  for  domestic  purposes 

Capf  a  thick,  strong  block  of  wood, 
with  two  holes  throughit, one  square 
and  the  other  round,  used  in  ship- 
building to  confine  together  the 
head  of  a  mast  and  the  lower  part 
of  that  next  above  it 

C^gtadty^  the  same  in  sense  as  content 
or  volume  in  pure  mathematics. 
In  physics  it  generally  signifies  the 
power  of  holduig  or  retaining:  thus 
we  speak  of  the  capacity  of  a  body 
for  heat,  &:c. 

Ct^fei,  in  mining,  a  stone  composed  of 
quartz,  schori,  andhomblende,  usu- 
ally occurring  in  one  or  both  walls 
of  a  lode,  and  more  frequently  ac- 
companying tin  than  copper  ores 

CtqnUary  attraction  and  repulsion. 
These  names  have  been  given  to  the 
properties  of  matter  which  cause 
the  ascent  above  or  descent  below 
the  level  of  the  surrounding  fluid 
which  takes  place  when  a  tube  of 
small  diameter  is  dipped  into  water, 
mercury,  &:c. 

Ogntalf  in  architecture,  the  head  or 
uppermost  part  of  a  column  or  pi- 
laster. The  capitals  of  the  columns 
constitute  the  principal  and  most 
obvious  indicial  mark  of  the  re- 
spective orders.  For  thos^  of  each 
of  the  three  classes  or  orders  a  cer- 
tain character  conformable  with  the 
rest  of  the  order  is  to  be  observed; 
but  that  attended  to,  further  re- 
striction  is  unnecessary.  Between 
several  examples,  all  decidedly  re- 
ferrible  to  one  and  the  same  order, 
very  great  special  differences  occur, 
and  there  might  easily  be  a  very 
great  many  more.  Although  the 
capital  itsdf  is  indispensable,  it  is 
10  only  iBSthetically,  and  not  out  of 
positive  necessity.  The  necessity  is 
only  artistic ;  decoration  of  the  kind 

"75 


there  must  be,  but  the  express  mod< 
of  it  is  one  of  those  matters  whicl 
should  be  left  to  design,  to  whicl 
it  properly  belongs.  Capitals  ari 
just  as  legitimate  subjects  for  th< 
exercise  of  taste  and  invention  ai 
anything  else  in  decorative  design 
The  capital  is  only  an  ornamental 
head  to  the  column,  and  therefore 
admits  of  being  as  freely  designed 
as  any  other  piece  of  ornament,  on 
the  conditions  of  itsbeing  accordant 
in  character  vrith  the  rest  of  the 
order,  and  of  forming  an  agreeable 
transition  from  the  shaft  of  the  co- 
lumn to  the  architrave 

CapitoKumf  a  temple  or  citadel  at 
Rome,  on  the  Tarpeian  rock :  it  was 
finished  by  Tarquinius  Superbus, 
and  consecrated  by  the  consul  M. 
Horatius, — was  burnt  in  the  time 
of  Marius,  and  rebuilt  by  Sylla,  — 
destroyed  a  second  and  third  time 
in  the  troubles  under  Vitellius  and 
Vespa^^,  and  lastly  raised  again 
by  Domitian.  Its  name  was  de- 
rived from  the  discovery  of  the 
head  of  TbUu$,  during  the  excava^ 
tion  of  the  earth  for  the  founda- 
tion. Q.  Catulus  consecrated  it  to 
Jupiter  Capitolinus,  and 'covered 
it  with  gilded  brass  tiles.  The 
steep  ascent  of  the  rock  was 
mounted  by  100  steps  on  the  side 
of  the  forum.  In  the  temple  were 
statues  of  gold  and  silver,  vessels 
of  those  metals  and  of  crystal,  and 
3000  brass  tables  on  which  the 
Roman  lavre  were  engraved 

Ceple  (in  Cornwall)  ttoneis  something 
like  limestone,  but  vnll  not  bum. 
The  walls  of  most  lodes  are  of  this 
kind,  and  therefore  it  is  common 
to  call  a  lode  by  the  name  of  its 
caple:  those  veins  which  abound 
virith  it  are  termed  caples  or  caple- 
lodes 

CapreoU,  the  pieces  of  timber  on  a 
roof,  which  serve  to  uphold  the 
axes  or  principals.  A  fork  inclined 
so  as  to  afford  support  to  anything 
was  formerly  called  a  Capreohu 

Capsa  or  Ct^«»/a,  a  box  for  holding 
books  among  the  Romans:  these 


CAP 


CARLISLE  TABLES. 


CAR 


boxes  were  usually  made  of  beech 
wood,  and  were  cylindiical  in  form 

Capsizet  to  overturn 

Capttanfin  naval  architecture,  a  strong 
massive  piece  of  timber  let  down 
through  the  decks  of  a  ship,  and 
resting  its  foot  or  axis,  which  is 
shod  with  iron,  in  an  iron  socket, 
called  a  saucer,  fixed  on  a  wooden 
block  or  standard,  called  the  step, 
resting  on  the  beams 

Captain^  in  mining,  an  experienced 
miner ;  one  who  directs  and  over- 
sees the  workmen  and  business  of 
a  mine 

Caracolf  a  term  sometimes  used  for  a 
staircase  in  a  helix  or  spiral  form 

Caradoc  formation^  the  uppermost  of 
the  two  great  divisions  of  the  lower 
Silurian  strata  of  Murchison,  seen 
principally  in  Shropshire,  Worces- 
tershire, Somersetshire,  &c.,  and  on 
the  eastern  borders  of  Wales 

Caravanserai^  a  building  in  the  East, 
expressed  in  our  version  of  the 
Scripture  by  the  term  Inn;  in 
Turkey  it  is  understood  to  be  a 
placeofaccommodationforstrangers 
and  travellers:  they  are  built  at 
proper  distances  through  the  roads 
of  theTurkish  dominions,  and  afford 
the  indigent  and  weary  traveller  an 
asylum  from  the  inclemency  of  the 
weather 

Carbouy  a  non- metallic  elementary 
solid  body,  which  is  widely  diffused 
throughout  nature.  The  purest  and 
at  the  same  time  the  rarest  form  in 
which  it  occurs  is  that  of  the  dia- 
mond ;  the  more  common  states  in 
which  it  is  met  with  are  those  of 
anthradte,  graphite,  and  coal :  an- 
other form  is  that  of  charcoal 

CarbonatCf  a  salt  composed  of  car- 
bonic acid  and  a  base.  The  chief 
varieties  are  described  under  their 
alkaline,  earthy,  and  metallic  bases 

Carburet t  a  compound  of  carbon  with 
nitrogen,  metals,  &c. 

Carcan  {The)  of  a  building  is  the 
naked  walls  and  the  rough  timber- 
work  of  the  flooring  and  quarter 
partitions  before  the  building  is 
plastered  or  the  floors  laid 

76 


CareoM-jraofing',  that  which  supports 
the  covering  by  a  grated  frame  of 
timber-work 

Career^  a  prison  or  gaoL  The  Roman 
prisons  were  divided  into  three 
stories,  one  above  the  other,  each 
of  which  was  appropriated  to  dis- 
tinct purposes 

Card'tnaking  machme,  an  arrange- 
ment of  wires  used  in  the  cotton 
manufacture,  for  disentangling  the 
fibres  of  cotton  preparatory  to  spin- 
ning 

CardOf  a  pivot  and  socket,  an  appa- 
ratus by  means  of  which  the  doors 
of  the  ancients  were  fixed  in  their 
places,  and  made  to  revolve  in 
opening  and  shutting 

Careeninfft  the  operation  of  heaving 
a  ship  down  on  one  side  by  the 
application  of  a  strong  purchase 
to  her  masts,  which  are  properly 
supported  for  the  occasion,  to 
prevent  their  breaking  vrith  so 
great  a  strain,  and  by  which  means 
one  side  of  the  bottom,  being 
elevated  above  the  surface  of  the 
water,  it  may  be  cleansed  or  re- 
paired 

Carina^  according  to  Cicero,  the  keel 
or  lowest  piece  of  timber  in  the 
frame-work  of  a  ship 

CSar/tnpr«,short  pieces  oftimber  ranging 
fore  and  aft  from  one  deck-beam  to 
another,  into  which  their  ends  are 
mortised :  they  are  used  to  sustain 
and  fortify  the  smaller  beams  of  the 
ship 

CarUale  TableSf  so  called  from  the  more 
recent  mode  of  making  calculations 
of  the  value  of  annuities  on  lives, 
based  on  the  average  duration  of 
human  life,  as  taken  at  Carlisle,  in 
Cumberland.  The  value  of  a  life 
annuity  depends  upon  the  manner 
in  which  it  is  presumed  a  large 
number  of  person8,similarly  situated 
with  the  buyer,  would  die  oflf  suc- 
cessively. .  Various  tables  of  these 
decrements  of  life,  as  they  are 
called,  have  been  constructed  from 
observations  made  among  diflTerent 
classes  of  lives.  Some  make  the 
mortality  greater  than  others ;  and, 


r 


CAR 


CARPENTRY. 


CAR 


of  course,  tables  which  give  a  large 
mortality  give  the  value  of  the  an- 
unity  smaller    than    those  which 
suppose  men  to  live  longer.  Those 
who  buy  annuities  would  therefore 
be  glad  to  be  rated  according  to 
tables  of  high   mortality,  or  low 
expectation    of  life;    while  those 
who  sell  them  would  prefer  receiv- 
ing the  price  indicated  by  tables 
which  give  a  lower  rate  of  morta- 
lity.     Hence  arise  bargains  or  sti- 
pulations according  to  either  the 
Northampton  or  Carlisle  tabulated 
rating  of  the  duration  of  life.     In 
assurances  the  reverse  is  the  case : 
the  shorter  the  time  which  a  man 
is  supposed  to  live,  the  more  must 
he  pay  the  office,  that  the  latter 
may  at  his  death  have  accumulated 
wherewithal  to    pay  the  amount. 
The  Northampton  tables,  formed 
by  Dr.  Price,  from  observations  of 
burials  at  Northampton,  as  com- 
pared  with  all  other  tables  of  au- 
thority, give  too  high  a  mortality 
at  all  the  younger  and  middle  ages 
of  life,  and,  consequently,  too  low 
a  value  of  the  annuity.    The  Car- 
lisle tables,  formed  by  Mr.  Milne, 
give  much  less  mortality  than  most 
of  the  old  tables,  and  therefore  a 
higher  value  of  the  annuities :  they 
have   been    proved    to  represent 
the  actual  state  of  life  among  the 
middle  classes 

Carmine  {colour)  9  a  name  originally 
given  only  to  fine  specimens  of  the 
tinctures  of  kermes  and  cochineal, 
and  denoting  generally  at  present 
any  pigment  which  resembles  them 
in  beauty,  richness  of  colour,  and 
fineness  of  texture :  hence  we  hear 
of  blue  and  other  coloured  car- 
mines, though  the  term  is  princi- 
pally confined  to  the  crimson  and 
scarlet  colours  produced  from 
cochineal  by  the  agency  of  tin 

Com,  in  Cornish  mining,  a  rock;  a 
heap  of  rocks ;  a  high  rock 

Carnagioni  (of  the  Italians),  a  colour 
which  differs  from  terra  puzzuoli 
in  its  hue ;  in  which  respect,  other 
variations  and  denominations  are 


produced  lif  dressing   and  com- 
pounding    ^  0 
Carol,  a  small  closet  or  enclosure  to 

sit  and  read  in 
Carpenfer't  tquare:  the  stock  and 
bUde  are  formed,  in  one  piece,  of 
plate-iron,  and  the  instrument  is 
thus  constructed  :~one  leg  is  18 
inches  in  length,  numbered  from 
the  exterior  angle ;  the  bottom  of 
the  figures  are  adjacent  to  the  in- 
terior edge  of  the  square,  and  con- 
sequently theu"  tops  to  the  exterior 
edge :  the  other  leg  is  12  iQches  in 
length,  and  numbered  from  the  ex- 
tremity towards  the  angle ;  the 
figures  are  read  firom  the  internal 
angle,  as  in  the  other  side ;  and 
each  of  the  legs  is  about  an  inch 
broad.    It  is  not  only  used  as  a 
square,  but  also  as  a  level,  and  as  a 
rule:  its  application  as  a  square 
^     and  as  a  rule  is  so  easy  as  not  to 
require  any  example;  but  its  use 
as  a  level,  in  taking  angles,  may  be 
thus  illustrated:  suppose  it  were 
required  to  take  the  angle  which 
the  heel  of  a  rafter  makes  with  the 
back,— apply  the  end  of  the  short 
leg  of  the  square  to  the  heel-point 
of  the  rafter,  and  the  edge  of  the 
square  level  across  the  plate ;  ex- 
tend a  line  from  the  ridge  to  the 
heel-point,  and  where  this  line  cuts 
the  perpendicular  leg  of  the  square, 
mark  the  inches:  this  will  show 
how  far  it  deviates  from  the  square 
in  12  inches 
Carpenters*  tools :  the  principal  tools 
used  in  the  rougher  operations  of 
carpentry  are  the  axe,  the  adze,  the 
chisel,  the  saw,  the  mortise  and 
tenon-gauge,  the  square,the  plumb- 
rule,  the  level,  the  auger,  the  crow, 
and  the  draw-bore-pin,  or  hook-pin, 
for  draw-boring 
Carpentry  is  the  art  of  combining 
,  pieces  of  timber  for  the  support  of 
any  considerable  weight  or  pres- 
sure. 

The  theory  of  carpentry  is 
founded  on  two  distinct  branches 
of  mechanical  science :  the  one  in- 
forms us  how  strains  are  propagated 


CAR 


CARTOON. 


CAR 


through  a  system  of  framing;  the 
other,  how  to  proportion  the  re- 
sistance of  its  parts,  so  that  all  may 
be  sufficiently  strong  to  resist  the 
strains  to  which  they  are  exposed. 
The  one  determines  the  stability 
of  position,  the  other  the  stability 
of  resistance.  Each  of  these  may 
be  considered  in  the  most  simple 
manner  the  subject  admits  of,  with 
the  addition  of  rules  and  practical 
remarks. 

Timber  is  wrought  into  Tarious 
forms  according  to  the  principles 
of  geometry ;  and  these  forms  are 
to  be  preserved  in  their  original 
shape  only  by  adjusting  the  stress 
and  strain  accorcUng  to  the  laws  of 
mechanics.  Hence  the  import, 
ance  of  studying  both  these  sciences 
is  evident,  and  particularly  the 
latter;  for  unless  the  stress  and 
strain  be  accurately  a4justed,  the 
most  careful  attention  to  geometri- 
cal rules,  and  the  most  skilful  work- 
manship, will  be  exerted  in  vain. 
If,  for  instance,  the  centre  of  an 
arch  were  to  be  drawn  and  worked 
ever  so  truly  to  the  curve  required, 
what  would  it  avail  if  the  centre 
changed  its  form  virith  every  course 
of  stone  laid  upon  it  ?  And  it  must 
be  remarked,  that  this  is  not  an 
imaginary  case,  but  one  that  has 
frequently  happened ;  and  not  only 
to  men  ignorant  of  mechanics,  but 
to  some  of  the  most  celebrated  en- 
gineers that  France  ever  produced. 

The  engineers  of  our  own  coun- 
try have  been  more  successful, 
having  succeeded  in  gradually  in- 
troducing a  better  principle  of  con- 
structing centres  than  our  neigh- 
bours. The  greatest  defect  of  the 
English  centres  is  now  an  excess 
of  strength,  which,  on  principles  of 
economy,  it  would  be  desirable  to 
avoid  in  erections  for  temporary 
purposes 
Carpentry t  in  civil  architecture,  is  the 
art  of  employing  timber  in  the  con- 
struction of  buildings. 

The  first  operation  of  dividing  a 
piece  of  timber  into  scantlings,  or 


boards,  by  means  of  the  pit-saw, 
belongs  to  sawing,  and  is  previous 
to  any  thing  done  in  carpentry. 

The  tools  employed  by  the  car- 
penter are  a  ripping-saw,  a  hand- 
saw, an  axe,  an  adze,  a  socket, 
chisel,  a  firmer  chisel,  a  ripping- 
chisel,  an  auger,  a  gimlet,  a  hammer, 
a  mallet,  a  pair  of  pincers,  and  some- 
times planes ;  but  as  these  are  not 
necessarily  used,  they  are  described 
under  the  head  of  joinery,  in  which 
they  are  absolutely  necessary 

Carrara  marble^  a  species  of  white 
marble:  it  is  distinguished  from 
the  Parian  or  statuary  marble  by 
being  hardier  and  less  bright.  It 
takes  its*  name  from  Carrara,  in 
Italy 

Carrel  J  a  pew,  closet,  or  desk,  with  a 
seat  placed  under  a  window,  where 
the  monks  were  engaged  in  copying 
writings 

Carriage  efa  stair,  the  timber  which 
supports  the  steps 

Carrick-bend,  a  kind  of  knot.  Car- 
rick.bitts  are  the  vrindlass-bitts 

Carrier,  the  piece  of  iron  which  is 
fixed  by  a  set.screw  on  the  end  of 
a  shaft  or  spindle  to  be  turned  in 
a  lathe,  to  carry  it  round  by  the 
action  of  the  driver  of  the  centre 
chuck 

Carry  away,  a  sea  term,  to  break  a 
spar  or  part  a  rope 

Cartoon,  a  distemper-coloured  draw. 
ing,  made  on  paper,  linen,  parch- 
ment, &c.,  of  the  exact  pattern  of 
a  design  intended  to  be  executed 
either  in  tapestry,  mosaics,  or  on 
glass:  such  are  Raphael's  divine 
pictures  in  Hampton  Court  Palace 

Cartoon,  in  painthig,  a  design  drawn 
on  strong  paper,  sometimes  after- 
wards calqued  through,  and  trana- 
ferred  on  the  fresh  plaster  of  a 
wall,  to  be  painted  in  fresco 

Cartouch,  the  same  as  modillion,  ex- 
cept  that  it  is  exclusively  used  to 
signify  the  blocks  or  modillions  oq 
the  eaves  of  a  house  < 

Cartouche,  an  ornament  representi^^  ' 
a  scroll  of  paper 

Carucru,  or  Chica,  a  new  pigment. 


CAR 


CASTELLA. 


CAS 


of  a  soft  powdery  texture  and  rich 
marrone  colour,  first  brought  from 
South  America  by  Lieut.  Mawe 

Cartfinff  and  inlaying  of  woods  had 
hecome  pretty  general  at  the  latter 
end  of  the  sixteenth  century :  "  at 
Hardwick,  in  Derbyshire  (15  70),the 
wood-work,  in  several  of  the  prin- 
cipal apartments,  is  oak,  inlaid  with 
ebony  ornaments  on  the  panels  and 
stiles.  The  doors  and  shutters  of 
'  Mary  Qneen  of  Scot's  room/  as  it 
is  called,  are  framed  in  panels  of 
light  wood,  inlaid  with  profiles  of 
the  Caesars,  and  other  enrichments ; 
the  stiles,  of  darker  coloured  oak. 
In  the  state-room,  tl^  walls  are 
divided,  at  about  half  the  height, 
by  a  stringing,  the  upper  part  filled 
with  landscapes,  figures,  and  ani. 
mals,  relieved  in  plaster,  and 
painted  in  their  proper  colours  on 
white  ground ;  and  the  lower  divi. 
sion  hung  with  tapestry.  The 
chimney  front  is  entirely  occupied 
byalarge  armorial  compartment,  re- 
Ueved  in  plaster  and  emblazoned" 

Caryates  or  Carya/M2e«(0reek),  figures 
used  instead  of  columns,  employed 
in  architecture '  to  represent  the 
portraiture  of  the  defeated  Persians 
after  the  subjugation  of  the  Carya- 
tas.  The  male  figures  are  denomi- 
nated Persians,  Telamones,  or  Atlan- 
tides :  the  female,  Caryans  or  Cary- 

atides 

Caryatides,  anthropostylar  pillars  or 
human  figures  (usually  female  ones) 
employed  instead  of  columns  to  sup- 
port  an  entablature.  Such  figures 
ought  always  to  be  perfectly  free 
from  all  attitudinizing,  and  to  ap- 
pear to  support  their  burden  with- 
out any  eflfort.  Some  very  matter- 
of-fact  critics  object  to  caryatides 
as  being  at  the  best  only  beautiful 
absurdities ;  as  if  statues  so  applied 
were  particularly  liable  to  be  mis- 
taken for  living  persons  subjected 
to  a  more  severe  punishment  than 
that  of  being  posted  up  in  a  niche, 
or  on  the  top  of  a  building 

Cata^  according  to  Vitruvius,a  cottage ; 
a  small  country-house 


Cated  tm,  in  Cornish  mining,  that 
which  is  re-framed  by  the  gentlest 
current  of  water,  and  prevented 
fit>m  running  off  the  fhune  by  turf 
placed  at  the  bottom 
Case^hardemnff,  The  hardness  and 
polish  of  steel  may  be  united,  in  a 
certain  degree,  with  the  firmness 
and  cheapness  of  malleable  iron,  by 
what  is  called  case-hardening,  an 
operation  much  practised,  and  of 
considerable  use 

Casemenif  a  frame  encTosing  part  of 
the  gUzing  of  a  window,  with 
hinges  to  open  and  shut ;  also  an 
early  English  name  for  a  deep 
hollow  moulding 

Ciuemeni,  the  same  as  'sootia,'  the 
name  of  a  hollowed  moulding 

(kuementt,  sashes  or  glass  frames 
opening  on  hinges  and  revolving 
upon  one  of  the  vertical  edges 

Case$f  in  Cornwall,  very  small  fissures 
in  the  strata  of  the  earth,  through 
which  small  streams  of  vmter  flow 
when  they  are  opened  by  the  work- 
ing underground,  greatly  to  the 
hindrance  of  the  workmen 

Caring  of  timber-work,  the  plastering 
a  house  all  over  on  the  outside  with 
mortar  and  then  striking  it  wet  by 
a  ruler  vrith  the  comer  of  a  trowel, 
or  the  like  instrument,  to  make  it 
resemble  the  joints  of  freestone, 
by  which  means  the  whole  house 
appears  as  if  built  thereof 

Cassel  earthy  or  Ctutle  earth,  an 
ochreous  pigment  of  a  brown  co- 
lour, more  inclined  to  the  russet 
hue 

Cturia  Fistula  is  a  native  vegetable 
pigment,  though  it  is  more  com- 
monly used  as  a  medicinal  drug 

Cagt,  to  pay  a  vessel's  head  off,  in 
getting  under  way,  on  the  tack  she 
is  to  sail  upon 

Cast  after  east,  in  Cornwall,  is  throw- 
ing up  of  tin  stuff,  &c.,  from  one 
stage  of  boards  to  another,  each 
cast  about  5  or  6  feet  high 

Castella,  square  towers  in  the  cele- 
brated  Roman  wallof  Severas,  which 
was  raised  to  separate  England  from 
Scotland 


79 


CAS 


CATARACT. 


CAT 


CeuteUated,  built  in  imitation  of  an 
ancient  castle 

CasteUum,  the  receptacle  in  which  the 
water  waa  collected  and  heated  for 
the  public  baths  of  the  Romans ;  a 
castle 

Coitnuft  among  sculptors,  the  taking 
casts  of  impressions  of  figures,  busts, 
medals,  leaves,  &c. 

Coating  oi  draperies:  by  this  term  i^ 
implied  the  distribution  of  the  folds, 
and  draperies  are  said  to  be  well 
cast  when  the  folds  are  distributed 
in  such  a  manner  as  to  appear 
rather  the  result  of  mere  chance 
than  of  art,  study,  or  labour.  In 
that  manner  or  style  of  painting, 
which  is  called  the  grandf  the  folds 
of  the  draperies  should  be  great, 
and  as  few  as  possible,  because 
their  rich  simplicity  is  more  sus- 
ceptible of  great  lights ;  but  it  is 
an  error  to  design  draperies  too. 
heavy  and  cumbersome,  for  they 
ought  to  be  suitable  to  the  figures, 
with  a  combination  of  ease  and 
grandeur.  Order,  contrast,  and  a 
variety  of  stuffk  and  folds,  consti- 
tute the  elegance  of  draperies;  and 
diversity  of  colours  in  these  stuffs 
contributes  extremely  to  the  har- 
ihony  of  the  whole  in  historic  com- 
positions 

Casting  or  Warping^  in  joinery,  is  the 
bending  of  the  surfaces  of  a  piece 
of  wood  from  their  original  posi- 
tion, either  by  the  weight  of  the 
wood  or  by  an  unequal  exposure  to 
the  weather,  or  by  the  unequal  tex- 
ture of  the  wood 

Cast-iron /rammgf  for  mill-work,  pos- 
sesses great  superiority  over  that 
of  timber,  for  constructing  the 
framing.  It  is  not  only  much 
more  durable,  but,  from  the  uni- 
formity of  its  texture,  may  be  con- 
verted into  any  shape,  so  as  to  give 
it  great  advantage  in  arranging  the 
materials  with  respect  to  strength, 
and  proportioning  it  to  the  stress 
it  has  to  sustain 

Cast-iron  shoes  for  roqft.  A  prac- 
tice has  been  recently  introduced 
into    the    construction    of    roofs 

80 


having  the  beams  of  wood,  of  pro- 
tecting their  extremities  from  the 
damp  and  consequent  decay  to 
which  they  are  liable,  by  resting 
immediately  in  contact  with  the 
brick,  or  stone  work  of  the  walls  of 
the  building.  This  is  effected  by 
what  th^  workmen  call  cast-iron 
shoes,  which  are  attached  to  the 
ends  of  the  tie-beams  by  means  of 
bolts,  nuts,  &c. 

The  iron  shoe  itself,  of  course, 
takes  various  forms,  according  to 
circumstances  and  the  situation 
where  it  is  introduced,  and  the 
jMffticular  views  of  the  architect 
who  employs  it. 

In  cases  where,  from  the  nature 
of  the  work  carried  on,  every  part 
is  exposed  to  great  heat  and  mois- 
ture, the  defence  afforded  by  such 
an  attachment  is  of  great  import- 
ance ;  the  wood,  unless  thus  pro- 
tected, being  of  course  very  liable 
to  decay  in  those  parts  where  damp 
and  moisture  might  accumulate 

Castlsj  a  fortified  and  strong  mansion, 
Situated  and  constructed  and  ar- 
ranged for  the  purpose  of  protect- 
ing its  inmates  against  the  assaults 
of  enemies ;  in  modem  use,  domes- 
tic residences  of  the  nobility  and 
gentry,  without  the  necessity  of 
being  garrisoned  by  armed  men 

Cat^  the  tackle  used  to  hoist  the  an- 
chor up  to  the  cat-head 

CatacombSf  subterraneous  vaults  or 
excavations  used  as  burying-places 

Catamaranf  a  name  given  both  in  the 
East  and  West  Indies  to  some  kinds 
of  rafts,  which  are  used  in  short 
navigations  along  the  sea-shore 

Cataractf  a  contrivance  applied  to 
Coraish  engines  for  regulating  the 
number  of  strokes  per  minute :  it 
consists  of  a  small  pump  fixed  on  a  | 
cistern  *,  the  piston  is  raised  at  each 
stroke  of  the  engine  by  a  tappet  on 
the  plug-rod,  and  the  water  rises 
into  the  cylinder  of  the  pump ;  it 
is  then  forced  through  a  cock  by 
means  of  counterweights  attached 
to  a  cross-head  on  the  pump  piston- 
rod:  when  the  water  has  beenforced 


CAT 


CATHEDRALS. 


CAT 


back  into  the  cistern,  a  series  of 
leyers,  acting  on  a  rising  rod,  loosen 
catches  which  allow  weights  to  act, 
by  means  of  levers,  to  open  or  shut 
the  steam,  equilibrium,  and  exhaust 
valves 

Cataractes,B,  cataract,  cascade,  or  sud- 
den  fall  of  water  from  a  higher  to 
a  lower  level ;  according  to  Pliny, 
a  sluice,  flood-gate,  or  lock  in  a 
river 

Catehf  a  contrivance  in  machinery, 
acting  on  the  principle  of  a  latch 

Catenary,  in  the  Wgher  geometry,  a 
mechanical  curve  which  a  chain  or 
rope  forms  itself  into  by  its  own 
weight,  when  hung  freely  between 
two  points  of  suspension,  whether 
these  points  be  in  the  same  hori- 
zontal plane  or  not 

CaigtU,  in  turnery,  the  string  which 
connects  the  fly  and  the  mandril 

Cai'harpm,  an  iron  leg  used  to  con- 
fine  the  upper  part  of  the  rigging 
to  the  mast 

Cat-head,  in  naval  architecture,  a  large 
square  piece  of  timber,  one  endjof 
which  is  fastened  upon  the  fore- 
castle and  the  other  end  projects 
without  the  bow,  so  as  to  keep  the 
anchor  clear  of  the  ship  when  it  is 
being  drawn  up  by  a  tackle 

Cathedra,  according  to  Horace,  a  chair 
without  arm  s ;  according  to  Juvenal, 
a  chair  with  a  long  deep  seat 

Cathedral,  the  principal  church  of  a 
diocese,  in  which  the  bishop's  throne 
is  placed 

Cathedral  (the  very  ancient)  of  Usum- 
bar  and  other  Armenian  churches 
in  Georgia  have    an  arcade  sur- 


rounding the  outside  of  the  build- 
ing, of  which  the  arches  are  in  the 
flattened  Gothic  style:  the  same 
form  prevails  in  the  windows,  doors, 
&c.,  in  the  body  of  the  church. 
These  structures  are  of  an  earlier 
date  than  any  Gothic  architecture 
in  Italy 

Cathedrals.  Very  few  of  the  Gothic 
cathedrals  on  the  Continent  have 
the  tower  or  spire  springing  from 
the  centre  of  the  cross,  and  resting 
on  four  pillars,  tobalance  the  thrusts 
of  the  ranges  of  arches  centering 
there ;  nor  have  those  of  Stras- 
burgh,  Ulm,  Vienna,  Orleans,  or 
Antwerp.  '*  The  distribution  of  light 
in  a  Gothic  cathedral  is  admirably 
adapted  to  the  grandeur  of  the  edi- 
fice, and  produces  that  effect  which 
a  painter  aims  at  in  his  picture.  At 
the  entrance  at  the  west,  the  win- 
^.r  dow  being  placed  high,  there  is  a 
low-toned  light  on  the  lower  part 
of  the  pillars,  and  a  jshadow  on  the 
pavement,  which,  as  we  walk  up  the 
nave,  graduates  into  light  from  the 
choir.  The  east  window,  always 
the  broadest  and  the  highest,  pours 
in  a  greater  body  of  hght  than  is  to 
be  found  in  any  other  kind  of  build- 
ing. The  altar,  rather  in  shadow, 
surrounded  by  this  strong  Ught, 
gives  additional  effect  by  contrast. 
The  light  from  the  transept  win- 
dows  is  softened  down  by  painted 
glass.  The  small  windows,  placed 
high  along  the  aisles,  enlighten  their 
roofs,  but  the  lower  part  of  the 
pillars  and  floor  remain  in  shadow.'' 

Cathedral  churches  of  Great  Britain : 


NAME. 

Aberdeen,  Old 
Andrew  (St.) 
Asaph  (St.) 
Bangor    • 
Bath  .     . 
Brechin   . 
Bristol     . 
Canterbury 
Carlisle    . 
Chester    . 
Chichester 


ORDEa. 

DATE. 

COUNTY. 

•         » 

1137 

Aberdeenshire 

• 

temp.  Alex.  I. 

Fifeshire 

»            * 

SecularCanons 

550 

Flintshire 

Do. 

550 

Caernarvonshire 

Benedictine 

676 
1140 

Somersetshire 
Forfar 

Augustine 

1148 

Somersetshire 

Benedictine 

616 

Kent 

Augustine 

686 

Cumberland 

Benedictine 

875 

Cheshire 

•          •       • 

SecularCanons 

1075 

Sussex 

81 


d5 


CAT 


CAUTIONS  IN 


CAU  ) 


•    •    • 


•    •    • 


•    •    • 


•    •    • 


NAMB. 

Coventry 

David's  (St.)    .    .    . 

Dornoch 

Dornoch.  •  .  .  • 
Dublin,  Cathedral  of  1 
the  Holy  Trinity  J 
Dumblain  • 
Donkeld .  . 
Durham  .  . 
Elgin .  •  . 
Ely  .  .  . 
Exeter  .  . 
Glasgow .  • 
Gloucester  . 
Hereford 
lona  .  .  . 
Lichfield .  . 
Lincoln  .  . 
lindisfame  . 
Llandafif .  . 
Manchester . 

Norwich 

Oxford 

Paul's  (St.).    .    .    . 
Peterborough  «    .    . 

Ripon 

Rochester    .... 

Ross 

Salisbury     •    .    .    . 

Wells 

Whitehom  .  .  .  . 
Winchester  .... 
Worcester  . 
York  .    .    . 


.    •    . 


... 


•    .    . 


ORDBR. 

Benedictine 
Secular  Canons 


Augustine 


Benedictine 

Dominican 

Benedictine 

Do. 

Augustine 

Benedictine 

SecularCanons 

Secular  Canons 

Benedictine 
SecularCanons 

Benedictine 

Aug^tine 

Do. 

Benedictine 

SecularCanons 

Benedictine 

SecularCanons 


Benedictine 

Do. 

SecularCanons 


DATB. 

1102 
577 


1170 


990 
1233 

673 
1050 
1270 

680 

825 

656 

635 

635 

635 

522 

9  Hen.  V. 

1096 

727 

604 

970 
Wm.  Conq. 

600 

905 
766 

963 
678 
627 


COUNTY. 

Warwickshire 
Pembrokeshire 
Caithness 
Sutherland 

Ireland 

Perthshire 

Do. 

Durham 

Moray 

Cambridgeshire 

Devonshire 

Renfrewshire 

Gloucestershire 

Herefordshire 

Argyleshire 

Staffordshire 

Lincolnshire 

Northumberland 

Glamorganshire 

Lancashire 

Norfolk 

Oxfordshire 

London 

Northamptonshire 

Yorkshire 

Kent 

Ross-shire 

Wiltshire 

Somersetshire 

Kircudbright 

Hampshire 

Worcestershire 

Yorkshire 


Catherine-wheelf  in  architecture,  an 
ornament  that  occurs  in  the  upper 
part  of  the  north  and  south  tran- 
septs of  ancient  cathedrals 

Cathetw.  The  eye  of  the  volute  is 
so  termed  because  its  position  is 
determined,  in  an  Ionic  or  voluted 
capital,  by  a  line  let  down  from  the 
point  in  which  the  volute  generates 

Cafs-paWf  a  hitch  made  in  a  rope 

CauUculfUt  the  volute  or  twist  under 
the  flower  in  the  Corinthian  capital 

Catdkinfff  in  naval  architecture,  the 
art  of  driving  a  quantity  of  oakum, 
t. «.  old  ropes  untwisted  and  sdft- 
ened,  into  the  seams  of  the  planks, 
to  keep  out  the  water 

Counter  and   Counting^  in  Cornish 

82 


mining.  Contra:  when  two  lodes 
run  across,  the  one,  with  respect 
to  the  other,  is  called  a  couaUer  or 
contra  lode 

Cautions  in  Architectural  Construe- 
tion. — 

UNION  OF  NBW  AND  OLD  WORK. 

In  attaching  any  new  work  to  a 
building,  every  allowance  must  be 
made  for  the  sinking  of  the  footings 
under  pressure,  and  for  the  settle- 
ment of  the  masonry  into  itself. 
Thus,  while  it  is  necessary  that  a 
vertical  groove,  or  indent,  be  made 
in  the  old  work,  to  receive  a  cor- 
responding piece  of  the  new,  it  is 
still  more  essential  that  a  freedom  I 


CAtf 


CONSTRUCTION. 


for  tbe  downward  motion  of  the 
latter  should  be  secured:  otberwiae, 
if  it  be  tightljr  toothed  and  bonded 
into  tbe  old  work,  tbe  result  illui- 
traled  in  the  Btineied  iketch  maf 
be  anticipated. 


FACING    WITH 

The  aame  caution  required  in 
the  latter  case  must  be  here  equally 
obseryed.  The  iacltitig  (compoaed 
of  tmall  material  and  much  mor- 
tar) will  settle  more  than  the /re*; 
and  the  latter  will  consequently 


bnlge.  Thil  is  eaiilj'  remedied  by 
compatmg  and  allowmg  for,  the 
diiference  of  settlement  and  by  a 
due  legard  to  the  occaiioaal  bond- 
ing; of  the  aibUr  ao  aa  to  make 
the  wall  one  substance  instead  of 
two  difTereutly  conditioned.  The 
preceding  sketch  lUuBtrales  the 
conieqnence  of  we  ght  presaing 
npon  unbonded  aahlar  and  upon 
yielding  nibble. 


in  which  the  points  a  and  a  were 
prevented  by  the  ioverted  arch 
from  aioking  with  the  poiuts  h  b, 
which  latter  sunk  the  more  from 
tbe  preiiure  of  the  srcb  c  in  the 
direction  of  the  dotted  lines.  It 
IS  not  uncommon  for  the  young 
architect  to  of  eel  precautionary 
$citnc*,  without  a  doe  considera- 
tion of  the  peculiar  drcunutancei 
of  his  case. 


Always  endeavour,  if  posiible,  to 
get  yoiir  water-closet  cea»-pit  out- 
side the  building,  so  that  it  may 
be  approached  for  cleansing  with- 
out disturbing  the  interior.  Be 
careful  in  tbe  efficient  use  of  dip- 
draps  to  prevent  the  ascent  of  tats 
from  the  outer  sewer  into  the 
drains  which  are  under  the  floors 
of  the  house.  Rats  are  destructive 
in  their  operadans,  and  if  tbey  die 
in  the  drain,  prove,  for  a  length 
of  dme,  an  unbearable  nuisance. 
Drains  may  serve  every  purpose  of 
carrying  off  soil  and  water ;  but 
the  slightest  opeuing  in  their  upper 
part  wUl  allow  the  escape  of  effluvia 
iato  the  space  under  the  ground 
flooring,  and  thence  into  the  rooms, 
unless  that  space  be  thoroughly 
ventilated  with  grated  openings, 
dlowiog  a  thorough  draught, — or, 
at  least,  a  free  ingress  of  fresh  air, 
and  equal  egress  of  foul.  In  tbe 
appUcatioQ    of  covered  diy  areas 


CAU 


CAUTIONS  IN 


CAU 


round  the  excavated  basements 
of  buildings,  on  no  account  omit 
their  entire  ventilation.  If  this  be 
not  attended  to,  the  main  walling, 
which  they  are  intended  to  preserve 
from  damp,  may  remain  even  more 
continually  moist  than  if  in  imme- 
diate connection  with  the  natural 
ground.  Moisture  frequently  rises 
up  the  walling  from  below  its 
foundation,  and,  exuding  from  the 
face  of  the  masonry,  remains  con- 
fined, unless  it  evaporate  and  es- 
cape. Without  means  to  this  end, 
a  covered  area  vrill  be  merely  a  re- 
ceptacle for  damp,  and  may  keep 
the  masonry  continually  wet,  even 
when  the  ground  outside  is  per- 
fectly  dry.  Be  especially  cautious 
that  the  water  from  the  rain-pipesof 
the  roofs  and  flats  be  not  conducted 
by  them  into  the  foundations. 

FIRB    OPENINGS. 

It  vnll  save  much  subsequent 
trouble  and  disturbance  of  masonry, 
to  be  assured  as  to  the  size  and 
character  of  the  stoves,  grates, 
ranges,  &c.,  which  the  proprietor 
will  employ.  In  the  kitchen  and 
cooking-rooms,  especially,  precau- 
tionary care  shoidd  be  taken  in 
suiting  the  openings  to  the  intended 
apparatus.  Do  not  forget  to  be 
prepared  for  a  smoke-jack,  &c. 

DWAB.F   WALLS. 

In  constructing  these,  do  not 
omit  the  holes,  &c.,  necessary  for 
under-floor  ventilation. 

PAVING. 

Be  careful  that  the  bottom,  on 
which  fine  paving  is  laid,  be  dry 
and  free  from  ttaining  material. 
Common  lime  mortar  is  often  in- 
jurious to  pavements.  Portland 
paving  is  especially  liable  to  be 
disfigured  by  it. 

WROUGHT  S^ONB-WORK. 

In  putting  wrought  stone-work 
together,  tron  is  to  be  avoided  as 
the  certain  cause  of  its  subsequent 
destruction.  The  stone  cornices, 
architraves,  and  dressings  of  many 
a  noble  mansion  have  been  brought 


into  premature  ruin  by  the  con- 
traction and  expansion  of  iron 
under  the  efiiects  of  cold  and  heat. 
But  there  are  careless  contractors 
who  will  allow  their  Corinthian 
capitals  and  fluted  shafts  to  be 
ruined,  even  before  the  entablature 
surmounts  them;  and  the  young 
architect  will  not,  therefore,  omit 
to  insert  a  clause  in  his  specifica- 
tion, (and  to  be  peremptory  in.  its 
enforcement,)  that  all  cut  stone- 
work be  securely  preserved,  daring 
the  progress  of  the  building,  with 
wood  casing.  It  is  surprising  how 
grossly  indifferent  each  class  of 
artificers  is  to  the  work  of  the 
others.  It  is  still  more  surprising 
to  observe  how  frequently  they 
seem  indifferent  to  tiie  preserva- 
tion of  tlleir  own. 

SLATING. 

Get  rid  of  the  masons  and  plas- 
terers and  plumbers  before  your 
slaters  begin.  The  injury  done  to 
slating  by  the  afterwork  of  chim- 
ney-tops, &c.,is  much  to  be  dreaded. 
The  cementitious  *  stopping'  to  a 
roof  will  not  be  eflSciently  done 
without  close  supervision :  the 
ridge,  hip,  and  valley  courses  will 
not  be  properly  formed  of  large  cut 
slates, — nor  will  every  slate  have 
its  two  nails,  unless  the  architect 
see  to  it. 

PLASTERING. 

Clear  may  be  your  specification 
in  forbidding  salt  sand,  but,  if  your 
work  be  carried  on  in  the  vicinity 
of  any  estuary,  the  chances  are 
(unless  you  be  deemed  cruelly 
strict)  that  the  surface  of  your  in- 
ternal walls  will  vary  vdth  the 
weather,  from  damp  to  dry,  like  a 
sea-weed,  and  throw  out  salt  in 
abundance. 

BEAMS,  JOISTS,  AND  OTHER  TIMBERS. 
LINTELS,  BOND,  PARTITIONS. 

It  is  the  office  of  walls  to  carry 
beams,  &c. ;  and  that  of  beams  to 
stay  the  walls  from  falling  out- 
wards  or  inwards:  but  it  is  the 
duty  of  architects  to  see  that  the 


CAU 


CONSTRUCTION. 


wood-work  whicb  supplants  ma. 
n>Di7  does  Dot  veaken  the  lattar ) 
i.  e.  that  the  eods  of  timbers  in- 
serted into  walls  toay  not,  bjr  com- 
pmaloa  or  decay,  leave  the  tn- 
perincumbent  tnasoiiT;  to  loosen 
downwards.  Thus,  the  beam  a, 
(bough  entering  only  a  parlion  of 


tbewall,  presses  upon  the  thorough- 
itoae  «,  which  throws  tbe  weight 
upon  the  tuAole  wall,  and  has,  by 
means  of  an  iron  plate  c,  s  hold  to 
secure  its  perpendicularity.  The 
cover-stone  c  presses  on  (he  surface 
of  the  tinber  to  confirm  i($  secu- 
ri(y :  but  should  tbe  timber 


e  will  B 


(.be- 


cause lustained  by  tbe  eide-stont . 
dd.  To  preeeni  rot,  the  backing 
isd  aide-stones  are  left  free  of  tbe 
timber,   so    that   air      -. p 

it.  Tbehabitofplac-  ZjiHtH 
iog  the  eods  of  beams  -^H^ 
on  a  template,  as  a,  |  i,  '  '  | 
ii  bad.  The  only  jus-  0 

tification  of  the  employment  of 
wood,  so  built  into  the  walls,  is 
when  it  forms  a  continuous  plate, 
that  it  may  act  as  a  bond  to  pre- 
•erre  the  perfect  homontal  level  of 
joists,  which,  however,  should  ex- 


tend a  little  beyond  tbe  plate,  so  as 
to  have  a  bearing  also  on  the  solid 
of  the  wall.  Careful  inspection 
will  then  so  manage  the  construe. 
6on  of  the  wall  in  this  part,  as  to 
kaie  it  but  little  weakened  by  the 
tir-boUows  required  for  the  plate 


and  joists ;  unless,  Indeed,  it  be 
very  thin,— m  only  one  brick,  for 
instance, — when  no  law  of  common 
sense  can  jusli^  the  nse  of  continu- 


mil 

'.  Mill  : 

I  111! 


ous  bond.    Where  joists  uninter. 
ruptcdiy  cross  a  tbin  wall,  wbi  ' 
is  to  support  another  story  of  n 
Boniy,  let  there  only  be  one  plate, 
thin,  and  an  its  edge,  in  the  centre 
of  tbe  wall,  so  that  at  least  a  brick 
on  edge  may  be  placed  on  each 
side  of  it,  to  fill  up  tbe  interve' 
between  the  joists,  and  give  sol 
support  to  the  superincumbent  m 
sonry.      On    no    account   let   tL_ 
upper  part  of  the  nail  be  separateil 
from  the  lower  by  a  mere  layer  of 
perishable  wood,  or  supported  by  a 
range  of  joists  on  their  edge.    It 
bas  often  been  seen  that  iron  hoc 
ing  should  be  more  used  than  it 
as  the  internal  bonding  of  walla. 


Lt  the  SI 


t  be  n 


membered,  that  bond  timbering  is 
necessary,  at  intervals,  to  receive 
the  nails  of  the  battening.  When, 
bowevei,  the  wall  is  thin,  it 
be  imperative  to  avoid  its  use, 
ploying  old  oak  bats  for  that  pur. 
pose.  In  short,  let  it  be  the  care 
of  the  young  architect,  >o  to  eon. 
trive  the  union  of  his  masonry  and 
carpentry,  aa  that  the  entire  re- 
moval of  the  latter  may  leave  the 
former  secure  in  its  own  strength. 
In  the  use  of  Knleli  especially,  he 
should  be  cautious.  They  are  uae- 
fol  as  bonds  to  unite  the  tops  of 


CAU 


CAUTIONS  IN 


CAU 


pien,  and  ai  means  for  the  fixing 
of  the  jomery;  but  they  ought 
never  to  be  trusted  to  as  a  lasting 
support  of  masonry  y — ^that  support 
being  always  really  aiforded  by  the 
relieying  segment  arch  above  the 
lintel.  A  bressummer  may  be 
termed  a  large  lintel ;  and  by  its 
adoption  here,  at  least,  the  support 
of  the  masonry  is  truly  intended. 
The  use  of  the  bressummer,  in  shop- 
front  openings,  is  an  evil  necessity 
to  -which  an  architect  must  often 
submit ;  and  all  that  he  can  do,  is 
to  make  the  best  of  a  bad  job,  by 
VfrougM'iion  trussing,  which  will 
at  least  give  adequate  ttrength, 
though  it  may  not  insure  perma- 
nent durability.  If  time  spare  it, 
fire  may  destroy  it ;  and  the  latter 
evil  is  not  to  be  met  even  by  iron, 
which,  if  vnx>nght,  will  bend, — ^if 
cast,  YhiSl  crack,  with  heat.  Let 
the  arch,  then,  or  some  modifica- 
tion of  it,  be  always  used — if  pos- 
sible. 

Partitions  of  wood  should  not  be 
left  to  the  sagacity  of  the  carpenter. 
Under  all  circumstances  where  they 
have  to  support  themselves  over 
voids,  or  to  bear,  or  participate  in 
the  bearing  of,  a  pressure  from 
above,  they  should  be  considered 
by  the  architect  in  his  specifica- 
tion, and  carefully  studied  in 
making  the  working  drawings.    It 


is  not  enough  merely  to  say,  that 
"  they  are  to  be  trussed  so  as  to  pre- 
vent any  injury  to  ceilings  by  their 
own  pressure  ;**  marginal  sketches 


should  be  made,  showing  the  dis- 
position of  the  skeleton  framing, 
vdth  whatever  iron-work  is  neces- 
sary to  its  security.  See,  for  in- 
stance, what  a  carpenter  may  do, 
unless  well  directed:  a  roof  c, 
bearing  partly  on  the  partition  a, 
when  it  should  have  borne  only  on 
the  walls ;  and,  instead  of  distress- 
ing the  partition,  should  ha,\e 
rather  held  it  suspended :  the  psr- 
tition  A  bearing  dovm  with  its  own 
weight,  and  that  of  the  roof,  on 
the  floor  b,  instead  .of  being  so 
truss-framed  in  its  length  as  to 
leave  the  floor  unconscious  of  its 
existence.  No  ignorance  in  the 
young  architect  is  presumed  as  to 
the  manner  of  doing  these  things ; 
he  is  merely  admonished  not  to 
imagine  that  they  are  so  obvious  ss 
to  be  done  without  his  guidance. 

In  the  framing  of  roofs,  give  a 
maximum  strength  to  the  purlins : 
the  undulating  surface  of  a  weakly- 
purlined  roof  will  soon  proclaim  its 
defect  in  this  particular.    The  po- 


sition of  the  principals  should  not 
be  observable  from  without. 

FLOORS  ;   SIMPLE  AND  FRAMED,  ETC. 

For  permanent  and  uniform 
strength,  there  is  no  floor  so  good 
as  one  composed  of  simple  joists, 
stiflfened  by  cross  bonding :  but,  in 
very  large  rooms,  there  is  more 
economy  in  the  compound  floor  of 
binders  and  joists,  or  of  joists, 
binders,  and  girders.  There  may 
be  particular  reasons  for  girders, 
&c. ;  as,  when  the  weight  of  the 
floor  has  to  be  thrown  upon 
piers,  and  not  on  a  continuous 
wall  of  uniform  strength:  but 
the  usual  motive  to  the  use  of  the 
compound  floor,  in  rooms  ^rhich 


86 


CAU 


CONSTRUCTION. 


CAU 


aaed  18  or  20  feet  in  width,  i*  t, 
legitinutte  economy  of  mateiuJa. 
ll  is  onl;  necesaarji  to  cautioii  the 
Toung  practitioner  on  the  neceuity 
of  considering,  that  girden  bsve  to 
perform  the  duty  of  ciDas-waUi; 
ibtt  they  iboiild  be  tnuaed  to 
prerent  their  '  saggiiig '  eren  with 
their  own  weight ;  that  their  icuit- 
Ung  thould  sllon  for  the  nealiening 
effbct  of  the  cuttings  made  into 
their  nibsiance  to  receive  the  tim- 
bers they  support;  that  their  truis«* 
■hotild  be  wholly  of  iron  (and  not 
pirtially  of  oak)  ;  and,  especially, 
that  the  end  of  each  ginier,  tn- 
■tead  of  being  notched  on  perish- 
(ble  template*  of  wood,  and  closely 
KDTODnded  with  mortar  and  mo- 
Hnry,  shoold  be  housed  in  a  carity 
wttb  an  iron  holding  -  plate ;  or 
iourted  into  a  cast-iron  boiing, 
notched  Into  a  thorough  -  itone, 
leniQg  a  apace  (howerec  snuUl) 
for  the  air  to  circulate  ahoat  it. 


^^^f  ..„1-| 


Bid  prevent  rot.  The  failure  of 
I  girder  sometimes  involves  the 
UluTG  of  all  the  rest  of  the  floor ; 
■Dd,  though  all  timbers  inserted 
in  masonry  should  have  a  more 
oiefol  regard  to  their  preiervatioo 
from  decay  than  it  is  usual  to  be- 
stow, it  will  be  readily  admitted, 
that  too  much  care  cannot  be  given 
In  those  leading  bearing  timbers, 
without  the  permaoent  duration  of 
which  the  durability  of  the  large 
remainder  ia  of  no  avaiL 

The  same  remarks,  qiplying  to 


CBILIHOS. 

To  procure  a  good  ceiling  in 
^gle-joist  floon    i' 


there  should  be  ceiling  joists  cross- 
ing below  the  others :  and  it  is  a 
question  whether  the  ceiling  joists, 
under  double-framed  Boors,  instead 
of  being  chase-mortised  into  the 
binders,  should  not  be  in  unbroken 
lengths  nailed  under  the  binders. 
Where  the  ceiling  joists  (is  under 
roofe)  ire  likely  to  be  trodden 
upon,  they  must  he  well  secured. 


Always  consider  whether  the 
occnpsnts  of  any  particnlai  room 
will  be  annoyed  by  noises  from  the 
rooms  below  or  above.  Sound 
boarding  and  pugging  considerably 
increase  the  weight  of  the  floor,  the 
scantling  of  whose  timbers  should, 
therefore,  be  thought  upon.  Water- 
cLoset  partitions   shoijd   be  well 


The  spsce  behind  the  skirtings 
is  often  a  thoronghfare 
for  mice,  which  also 
0  travel  from 


the 


boUows  of  the  quarter- 
parti  tioos,  and  became 
in  several  ways  a  great 
nuisance.  Plaster  oi 
wood  stopping  is  not 
always  so  efficadoas  u 
the  use  of  broken  glass 
in  those  secret  passages  which  they 
are  prone  to  frequent. 


TF 


The  liability  of  gutters  and  ds- 
teiss  to  become  choked  with  snow, 
or  filled  up  with  leaves,  &c.,  renders 
it  advisable  to  protect  them  with  a 
boarded  covering,  which  may  pre. 
serve  the  under  caiient  of  water 
from  receiving  what  may  speedily 
produce  a  chokage  or  overflow. 


On  this  moat  important  subject 
the  young  architect  should  not 
move  a  step  without  carefully  con- 
sulting the  experienced  linowledge 
of  the  engineer.   Tredgold's  '  Prac. 


CAV 


CEILINGS. 


CEL 


tical  Essay  on  the  Strength  of  Cast 
Iron'  should  he  well  studied, 
-whenever  necessity  compeis  the 
support  of  heavy  and  loaded  su- 
perstructures hy  iron  columns  and 
heams.  A  careful  computation  of 
the  weight  of  the  mere  huilding, 
added  to  that  of  its  possihle  hur- 
then,  with  allowance  for  theoretical 
fallacy,  and  a  due  estimate  of  the 
increased  strength  of  the  hollow 
pillar,  as  compared  with  a  solid 
one  having  the  same  amount  of 
metal,  must  he  made,  examined, 
and  re-examined,  before  the  speci- 
fication be  issued. 

CaviBdiufnt  one  of  the  courts  of  a 
Roman  house,  most  commonly  sur- 
rounded  by  a  covered  passage, 
having  the  middle  area  exposed  to 
the  air 

CaviBdia.  There  are  five  kinds  of 
cavsedia,  which,  from  their  mode 
of  construction,  are  severally  deno- 
minated  Tuscan,  Corinthian,  tetra- 
style,  displuviatum,  and  testudi- 
natum.  They  are  termed  Tuscan 
when  the  beams  which  are  thrown 
across  the  court  have  timbers  and 
gutters  extending  diagonally  from 
the  angles  made  by  the  walls  of  the 
court  to  those  made  by  the  junction 
of  the  beams,  and  the  rafters  of  the 
eaves  are  made  to  incline  every 
way  towards  the  centre  of  the  com- 
pluvium.  The  timbers  and  com- 
pluvia  of  Corinthian  cavsedia  have 
a  disposition, in  all  respects,  similar; 
but  beams  are  made  to  project  from 
the  walls,  and  are  supported  upon 
columns  arranged  around  the  court 

Cavaziorit  in  architecture,  the  hollow 
trench  made  for  laying  the  founda- 
tion of  a  building;  according  to 
Yitruvius,  it  ought  to  be  one-sixth 
part  of  the  height  of  the  whole 
building 

CemettOt  a  hollow  moulding  whose 
profile  is  a  quadrant  of  a  circle; 
principally  used  in  cornices 

Cedar.  Cedar  wood  was  known  and 
used  in  the  earliest  times,  as  in  the 
construction  of  Solomon's  Temple: 

88 


great  varieties  are  produced  in  the 
eastern  and  western  parts  of  the 
world:  it  is  used  in  ship-build- 
ing, cabinet-work,  pencil-making, 
and  for  various  other  purposes 

CeiUngt  the  upper  side  of  an  apart- 
ment, opposite  to  the  floor,  gene- 
rally finished  with  plastered  work. 
CeiUngiB  are  set  in  two  difiTerent 
ways:  the  best  is  where  the  setting- 
coat  is  composed  of  plaster  and 
putty,  commonly  called  '  gauge.' 
Commpn  ceilings  have  plaster,  but 
no  hair :  the  latter  is  the  same  as 
the  finishing  coat  in  walls  set  for 
paper 

Ceilinff,  the  under  covering  of  a  roof, 
under  the  surface  of  the  vaulting  in 
vaulted  rooms  and  buildings.  Ceil- 
ings in  buildings  of  any  dimensions 
at  either  story  are  the  upper  or  over- 
head surfaces  of  the  rooms  respect- 
ively 

Ceilingi,  "When  ceilings  are  covered, 
the  height  of  the  cove  should  be 
regulated  by  the  total  height  of  the 
room.  In  proportioning  the  height 
of  a  room  to  its  superficial  dimen- 
sions, the  best  proportion  for  the 
cove  is  one-quarter  of  the  whole 
height 

Celerity  is  the  velocity  or  swiftness 
of  a  body  in  motion;  or  that  affec- 
tion of  a  body  in  motion  by  which 

*  it  can  pass  over  a  certain  space  in 
a  certain  time 

Cettf  an  enclosed  space  within  the 
walls  of  an  ancient  temple;  a  term 
applied  also  to  monkish  sleeping- 
rooms  in  religious  establishments 

Celhi  the  body  or  principal  part  of  a 
temple, —  anciently  written  cela. 
It  is  thought  to  be  derived  from 
eelanduSt — to  be  concealed  or  shut 
out  from  public  view;  because  in 
early  temples  the  cella  could  only 
be  entered  by  privileged  persons 

Cellarino,  that  part  of  the  capital  in 
the  Roman,  Doric,  and  Tuscan 
orders  which  is  below  the  annulets 
under  the  ovolo 

Cementation  is  the  process  of  con- 
verting iron  into  steel,  which  is 
done  by  stratifying  bars  of  iron  in 


CEM 


CEMENTS. 


CEM 


charcoal,  igniting  it»  and  letting 
them  continue  in  a  kiln  in  that  state 
for  five  or  six  days :  the  carbon  of 
the  charcoal  is  thus  absorbed  by 
the  iron,  and  the  latter  converted 
into  steel 
Cementf,  natural  When  the  propor- 
tion of  clay  in  calcareous  minerals 
exceeds  27  to  30  per  cent.,  it  is 
seldom  that  they  can  be  conyerted 
into  lime  by  calcination ;  but  they 
then  furnish  a  kind  of  natural  ce- 
ment, which  may  he  employed  in 
the  same  manner  as  plaster  of 
Paris,  by  pulverizing  it,  and  knead- 
ing it  with  a  certain  quantity  of 
water. 

There  are  some  natural  cements 
which  do  not  set  in  water  for  many 
days,  and  some  which  harden  in 
less  than  a  quarter  of  an  hour: 
these  last  are  the  only  ones  which 
have  been  made  use  of  at  present. 
Though  very  useful  in  circum- 
stances where  a  quick  solidification 
is  indispensable,  they  are  far  from  • 
ttOfbrding,  in  ordinary  cases,  the 
advantages  of  hydraulic  mortars  or 
cements  of  good  quality.  In  fact, 
they  merely  adhere  to  the  stone, 
owing  to  the  roughness  of  its  sur- 
face, and  the  entanglement  result- 
ing from  it;  and,  however  dexterous 
or  experienced  the  workman  may 
be  who  makes  use  of  them,  he  will 
be  unable  to  connect  the  different 
parts  of  his  masonry  in  one  conti- 
nuous bond  by  means  of  them. 
This  statement  must  be  understood 
to  apply  only  to  cements  which 
harden  while  in  contact  with  bricks 
under  water,  because  the  adhesion 
of  such  as  dry  in  the  open  air  is 
well  known  to  be  much  greater 
than  what  would  be  caused  merely 
by  asperities  of  the  surface.  It  is 
not  uncommon  to  see  from  twenty 
to  thirty  bricks  stuck  to  one  an- 
other by  Roman  cement,  and  pro- 
jecting at  right  angles  from  the 
side  of  a  wall,  as  a  proof  of  the 
excellence  of  the  composition;  and 
an  instance  has  been  mentioned  in 
which  thirty-three  bricks  were  suc- 

~l9 


cessfully  supported  in  this  manner. 
Now,  if  we  assume  the  weight  of  a 
brick  and  its  corresponding  joint 
of  cement  to  be  6  ths.,  and  their 
thickness,  when  the  bricks  were 
joined  one  to  another  in  the  man- 
ner above  alluded  to  (in  which  the 
longest  dimension  of  the  brick  was 
placed  vertically),  to  be  2^  inches, 
then  the  cohesive  force  necessary 
to  unite  the  first  brick  to  the  wall, 
with  sufiSdent  firmness  to  bear  the 
strain  occasioned  by  the  weight  of 
the  remaining  thirty-two  supported 
by  it,  must  have  been  nearly  91  ths. 
per  square  inch,  or  equivalent  to  a 
direct  load  of  3640  lbs.  upon  its 
whole  surface  of  about  40  square 
inches. 

That  which  is  in  England  very 
improperly  termed  Roman  cement 
is  nothing  more  than  a  natural  ce- 
ment, resulting  from  a  slight  calci- 
nation of  a  calcareous  mineral, 
containing  about  31  per  cent,  of 
ochreous  clay,  and  a  few  hundredths 
of  carbonate  of  magnesia  and  man- 
ganese. A  very  great  consumption 
of  this  cement  takes  place  in  Lon- 
don; but  its  use  will  infallibly  be- 
come restricted,  in  proportion  as 
the  mortars  of  eminently  hydraulic 
lime  shall  become  better  known, 
and,  in  consequence,  better  appre- 
ciated. 

Very  recently,  natural  cements 
have  been  found  in  Russia  and  in 
France.  They  may  be  composed  at . 
once  by  properly  calcining  mix- 
tures made  in  the  average  propor- 
tions of  66  parts  of  ochreous  clay 
to  100  parts  of  chalk.  It  is  fair, 
however,  to  admit,  that  no  artificial 
product  has  yet  been  proved  to 
equal  the  English  cement  in  point 
of  hardness. 

The  pure  calcareous  substances, 
when  imperfectly  calcined,  be- 
come converted  into  sub -carbon- 
ates, possessed  of  certain  proper- 
ties. These  properties  are  to  afford 
a  powder,  which,  when  kneaded 
with  water  in  the  same  way  as 
plaster  of  Paris,  acquires  in  it,  at 


CEN 


CENTRE  FRAMES. 


CE^ 


first,  a  consUtency  more  or  less 
firm,  but  which  does  not  continue 
its  progress  at  the  same  rate. 

The  argillaceous  limestones,  and 
the  artificial  mixtures  of  pure  lime 
and  clay  in  the  proportions  requi- 
site  to  constitute  hydraulic  lime  by 
the  ordinary  calcination,  become 
natural  or  artificial  cements  when 
they  have  been  subjected  merely 
to  a  simple  incandescence,  kept  up 
for  some  hours,  or  even  for  some 
minutes.  This  result,  which  has 
often  occurred  in  the  course  of 
first  experiments  in  burning  the 
artificial  hydraulic  limestones,  has 
been  equally  observed  in  Russia  by 
Colonel  Raucourt;  and  M.  Lacor- 
daire,  Engineer  of  Roads,  has  not 
only  fidly  verified  it  with  respect  to 
the  different  argillaceous  limestones 
of  the  neighbourhoodof  Pouilly,but 
has  aho  made  a  useful  and  happy 
application  of  it  in  the  works  which 
have  been  erected  at  the  junction  oC 
the  Burgpindy  canal;  both  in  trans- 
forming these  limestones  into  na- 
tural cements,  and  in  turning  to 
account  the  laxge  quantity  of  half- 
burnt  lime  which  is  found  in  the 
upper  layers  of  the  kilns,  when  the 
intensity  and  duration  of  the  heat 
is  80  regulated  as  not  to  exceed  the 
limit  proper  for  the  lower  strata  of 
the  charge. 

^  The  history  of  these  new  cements 
wiU  not  b9  complete  until  authentic 
and  multiplied  experiments  shall 
have  established  their  power  to 
resist  the  effects  of  air  and  frost, 
and  the  degree  of  adhesion  with 
which  they  unite  to  the  building- 
stone 

Cenotaphium,  a  cenotaph,  an  empty 
or  honorary  tomb,  erected  by  the 
Greeks  as  a  memorial  of  a  person 
whose  body  was  buried  elsewhere, 
or  not  found  for  burial 

CensitoreSf  surveyors  of  the  Roman 
aqueducts 

CetUauVf  poetically,  and  in  ancient 
mythology,  a  being  represented  as 
half  man,  half  horse ;  the  Sagitta- 
rius of  the  Zodiac 

90 


Centering,  temporary  supports,  prin. 
cipally  of  timber,  placeii  and  affixed 
under  vaults  and  arches  to  sustain 
them  while  they  are  in  course  oi 
building.  Much  ingenuity  is  dis- 
played in  the  centering  for  bridges 
and  tunnels 

Centigrade,  the  division  into  grades 
or  degrees  by  hundredth  parts; 
called  alto  centesimals 

Central  forces,  the  powers  which 
cause  a  moving  body  to  tend  to- 
wards or  recede  from  the  centre  of 
motion.  When  a  body  is  made 
to  revolve  in  a  circle  round  some 
fixed  point,  it  will  have  a  continued 
tendency  to  fly  off  in  a  straight  line 
at  a  tangent  in  the  circle,  which 
tendency  is  called  the  centrifugal 
force;  and  the  opposing  power  by 
which  the  body  is  retained  in  the 
circular  path  is  called  the  centri- 
petal force 

Centre,  any  timber  frame,  or  set  of 
-fellies,  for  i^upporting  the  arch- 
stones  of  a  bridge  during  the  con- 
struction of  an  arch. 

The  qualities  of  a  good  centre 
consist  in  its  being  a  sufficient  sup- 
port for  the  weight  or  pressure  of 
the  arch-stones,  without  any  sen- 
sible change  of  form  taking  place 
throughout  the  whole  progress  of 
the  work,  from  the  springing  of 
the  arch  to  the  fixing  of  the  key- 
stone :  it  should  be  capable  of  being 
easily  and  safely  removed,  and  de- 
signed so  that  it  may  be  erected  at 
a  comparatively  small  expense. 

In  navigable  rivers,  where  a  cer- 
tain space  must  be  Idft  for  the  pas- 
sage of  vessels,  and  in  deep  and 
rapid  rivers,  where  it  is  dif^cult  to 
establish  intermediate  supports, 
and  where  much  is  to  be  appre- 
hended from  sudden  floods,  the 
frames  should  span  the  whole  width 
of  the  archway,  or  be  framed  so  as 
to  leave  a  considerable  portion  of 
the  archway  unoccupied.  In  such 
cases,  a  considerable  degree  of  art 
is  required  to  make  the  centre  an 
effectual  support  for  the  arch- 
stones,  particularly  when  the  arch 


CEN 


CENTRE-DRILL. 


CEN 


is  luge.  But  in  narrow  riven,  and 
in  those  where  the  above-mentioned 
inconveniences  do  not  interfere 
with  the  work,  the  framing  may  be 
constructed  upon  horizontal  tie- 
beams,  supported  in  several  places 
by  pili»,  or  frames  fixed  in  the  bed 
of  the  river ;  and  the  construction 
is  comparatively  easy. 

In  large  arches,  when  the  arch- 
stones  are  laid  to  a  considerable 
height,  they  often  force  the  centre 
out  of  form,  by  causing  it  to  rise 
at  the  crown ;  and  it  is  sometimes 
necessary  to  load  the  centre  at  the 
crown  to  prevent  such  rising ;  but 
tbis  is  a  Yery  imperfect  remedy. 
Notwithstanding  the  subject  has 
been  considered  by  several  very 
eminent  men,  their  works  are  not 
much  calculated  to  instruct  the 
carpenter  how  to  avoid  this  diffi- 
colty;  indeed,  their  object  seems 
to  have  been  exclusively  to  calcu- 
late the  strength  of  a  centre  al- 
ready designed,  instead  of  showing 
the  principles  on  which  it  ought  to 
be  contrived ;  and  even  in  calcu- 
lating the  strength,  they  are  very 
imperfect  g^des,  because  they  have 
not  attempted  to  find  what  forces 
would  derange  a  centre,  but  only 
the  force  that  might  be  supported 
without  fracture. 

Cm/re,  in  a  general  sense,  denotes  a 
point  equally  remote  from  the  ex- 
tremes of  a  line,  surface,  or  solid : 
the  word  signifies  a  point 

CetUre-bitf  in  joinery,  an  instrument 
with  a  projecting  conical  point 
nearly  in  the  middle,  called  the 
centre  of  the  bit :  on  the  narrow 
vertical  surface,  the  one  most  re- 
mote from  the  centre,  is  a  tooth 
with  a  cutting  edge.  The  undco* 
edge  of  the  bit  on  the  other  side  of 
the  centre  has  a  projecting  edge 
inclined  forward.  The  horizontal 
section  of  this  bit  upwards  is  a 
rectangle.  The  axis  of  the  small 
cone  in  the  centre  is  in  the  same 
straight  line  as  that  of  the  stock ; 
the  cutting  edge  of  the  tooth  is 
more  prominent  than  the  projecting 

91 


edge  on  the  other  side  of  the  oen* 
tre,  and  the  vertex  of  the  conic 
centre  is  still  more  prominent  than 
the  cutting  edge  of  the  tooth. 

The  use  of  the  centre-bit  is  to 
form  a  cylindric  excavation,  having 
the  upper  point  of  the  axis  of  the 
intended  hole  given  on  the  surftce 
of  the  wood.  The  centre  of  the  bit 
is  first  fixed  in  this  point ;  then,  by 
placing  the  axis  of  the  stock  and 
bit  in  the  axis  of  the  hole  intended 
to  be  bored,  with  the  head  of  the 
stock  against  the  breast,  and  by 
turning  the  stock  swiftly  round  by 
means  of  the  handle,  the  hollow 
cone  made  by  the  centre  will  cause 
the  point  of  the  tooth  to  move  in 
the  drcumference  of  a  circle,  and 
cut  the  cylindric  sur&oe  progres- 
sively as  it  is  turned  round,  while 
the  projecting  edge  upon  the  other 
side  of  the  centre  will  cut  out  the 
cone  in  a  spiral-formed  shaving. 
Centre-bits  are  of  various  sizes,  for 
bores  of  different  diameters. 

Centre-ehuckf  a  chuck  which  can  be 
screwed  on  the  mandril  of  a  lathe, 
and  has  a  hardened  steel  core  or 
centre  fixed  in  it;  also  a  projecting 
arm  or  driver 

Centre-drUli  &  small  drill  used  for 
making  a  short  hole  in  the  ends  of 
a  shaft  about  to  be  turned,  for  the 
entrance  of  the  lathe  centres 

Centre  qf  attraction  ot  a  body  is  that 
point  into  which,  if  all  its  matter 
were  collected,  its  action  upon  any 
remote  particle  would  still  be  the 
same  as  it  is  while  the  body  re- 
tains its  own  proper  form ;  or  it  is 
that  point  to  which  bodies  tend  by 
their  own  gravity,  or  about  which 
a  planet  revolves  as  a  centre,  being 
attracted  or  impelled  towards  it  by 
the  action  of  gravity.  The  common 
centre  of  attraction  of  two  or  more 
bodies  is  used  to  denote  that  point 
in  which,  if  a  particle  of  matter 
were  placed,  the  action  of  each 
body  upon  it  would  be  equal,  and 
where  it  will  remain  in  eqiuUbrium, 
having  no  tendency  to  move  one 
way  rather  than  another 


CEN 


CENTRES. 


CEN 


Centre  of  a  circlet  that  point  in  a 
circle  which  is  eqaally  distant  from 
every  point  of  the  circumference, 
being  that  from  which  the  circle  is 
described 

Centre  of  a  conic  eeetiony  that  point 
which  bisects  any  diameter,  or  that 
point  in  which  all  the  diameters 
intersect  each  other.  This  point 
in  an  ellipse  is  within  the  figure,  in 
the  hyperbola  without,  and  in  the 
paraboU  it  is  at  an  infinite  dis- 
tance 

Centre  of  conversiont  a  mechanical 
term,  the  signification  of  which  may 
be  thus  conceived:  if  a  stick  be 
laid  on  stagnant  water,  and  drawn 
by  a  thread  fastened  to  it,  so  that 
the  thread  makes  always  the  same 
angle  with  it,  the  stick  will  be 
found  to  turn  about  a  certain  point; 
which  point  is  called  the  *  centre 
of  conversion  * 

Centre  of  a  curve  of  the  higher  kind, 
is  the  point  where  two  diameters 
concur;  and  when  all  the  diameters 
concur  in  the  same  point,  it  is 
called  the  general  centre 

Centre  of  a  dial^  that  point  where 
the  gnomon  or  style,  placed  par- 
allel  to  the  axis  of  the  earth,  inter- 
sects the  plane  of  the  dial 

Centre  of  an  equilibrium  is  the  same 
with  respect  to  bodies  immersed  in 
a  fluid  as  the  centre  of  gravity  is 
to  bodies  in  free  space,  or  it  is  a 
certain  point  on  which,  if  a  body, 
or  system  of  bodies,  be  suspended, 
,  they  vnll  rest  in  any  position 

Centre  of  friction  is  that  point  in  the 
base  of  a  body  on  which  it  revolves, 
in  which,  if  the  whole  surface  of 
the  base  and  the  mass  of  the  body 
were  collected  and  made  to  revolve 
about  the  centre  of  the  base  of  the 
given  body,  the  angular  velocity 
destroyed  by  its  friction  would  be 
equal  to  the  angular  velocity  de- 
stroyed in  the  given  body  by  its 
friction  in  the  same  time 

Centre  of  gravity  of  any  body,  or  sys- 
tem of  bodies,  is  that  point  upon 
which  the  body  or  system  of  bodies 
acted  upon  only  by  the  force  of 

92 


gravity  will  balance  itself  in  all 
positions ;  or  it  is  a  point  on  which, 
when  supported,  the  body  or  sys- 
tem will  be  supported,  however  it 
may  be  situated  in  other  respects. 
Hence  it  follows,  that  if  a  line  or 
plane  passing  through  the  centre 
of  gravity  be  supported,  the  body 
or  system  will  idso  be  supported ; 
and  conversely,  if  a  body  or  system 
balance  itself  upon  a  line  or  plane, 
in  all  positions,  the  centre  of  gravity 
is  in  that  line  or  plane.  In  a  simi- 
lar manner  it  will  appear,  that  if  a 
body  rest  in  equilibrio  when  sus- 
pended from  any  point,  the  centre 
of  gravity  of  that  body  or  system 
is  in  the  perpendicular  let  fall  from 
the  centre  of  suspension;  and  on 
these  principles  depends  the  me- 
chanical method  of  finding  the  cen- 
tre of  gravity  of  bodies 

Centre  rf  gyration^  that  point  in  a 
body  revolving  on  an  axis,  into 
which,  if  the  matter  of  the  whole 
body  were  collected,  the  same  an- 
gular velocity  would  be  generated 
by  the  same  moving  force 

Centre  of  motion  of  a  body  is  a  fixed 
point  about  which  the  body  is 
moved ;  and  the  axis  of  motion  is 
the  fixed  axis  about  which  it  moves 

Centre  of  osciUettion,  the  point  in 
which  the  whole  of  the  matter 
must  be  collected,  in  order  that  the 
time  of  oscillation  may  be  the  same 
as  when  it  is  distributed 

Centre  qf  percuseiont  that  point  of  a 
revolving  body  which  would  strike 
an  obstacle  with  the  same  force  as 
if  the  whole  of  the  matter  were 
collected  in  it 

Centre  of  positiont  in  mechanics,  de- 
notes a  point  of  any  body,  or  system 
of  bodies,  so  selected  that  we  may 
properly  estimate  the  situation  and 
motion  of  the  body  or  system  by 
those  points 

Centre  ofprewurey  or  meta  centre  of 
a  fluid  against  a  plane,  is  that  point 
against  which  a  force  being  applied, 
equal  and  contrary  to  the  whole 
pressure,  it  will  sustain  it,  so  as 
that  the  body  pressed  on  will  not 


CBN 


CHAINS. 


CHA 


iDdine  to'  either  side.  This  is  the 
same  as  the  centre  of  percussion, 
supposing  the  axis  of  motion  to  be 
at  the  intersection  of  this  plane 
with  the  surface  of  the  fluid ;  and 
the  centre  of  pressure  upon  a  plane 
parallel  to  the  horizon,  or  upon  any 
plane  where  the  pressure  is  uniform, 
is  the  same  as  the  centre  of  gravity 
of  that  plane 

Centre  of  gponianeous  rotation,  that 
point  which  remains  at  rest  the  in- 
stant a  body  is  struck,  or  about 
which  the  body  begins  to  revolve. 
If  a  body  of  any  size  or  form,  after 
rotatory  or  g3a^tory  motions,  be 
left  entirely  to  itself,  it  will  always 
have  three  principal  axes  of  rota- 
tion; that  is,  all  the  rotary  motions 
by  which  it  is  effected  may  be  con- 
stantly reduced  to  three,  which  are 
performed  round  three  axes  per- 
pendicular to  each  other,  passing 
through  the  centre  of  gravity,  and 
always  preserving  the  same  position 
in  absolute  space,  while  the  centre 
€i  gravity  is  at  rest,  or  moves  uni- 
formly forward  in  a  right  line 

Centre  phonic,  in  acoustics,  the  place 
where  the  speaker  stands  in  making 
polysyllabical  and  articulate  echoes 

Centre  phonocantpiiCf  the  place  or 
object  which  returns  the  voice 

Centre-punch,  a  small  piece  of  steel 
with  a  hardened  point  at  one 
end 
Centres,  in  turnery,  are  the  two  cones 
with  their  axes  horizontally  posited 
for  sustaining  the  body  while  it  is 
turned 
Centre-velic  or  Velic-pomt,  the  centre 
of  gravity  of  an  equivalent  sail,  or 
that  single  sail  whose  position  and 
magnitude  are  such  as  cause  it  to 
be  acted  upon  by  the  wind  when 
the  vessel  is  sailing,  so  that  the 

j    motion  shall  be  the  same  as  that 

I     which  takes  place  while  the  sails 

I     have  their  usual  positions 

I  Centrijitgal  force   is  that  force  by 

I  which  a  body  revolving  about  a 
centre,  or  about  another  body,  has 
a  tendency  to  recede  from  it 

\CentHfitgalpwfnp,  a  machinefor  raisin 


»S 


water  by  centrifugal  force  combined 
with  the  pressure  of  the  atmo- 
sphere 

Centr^tal  force  is  that  force  by 
which  a  body  is  perpetually  urged 
onwards  to  a  centre,  and  thereby 
made  to  revolve  in  a  curve  instead 
of  a  right  line 

Cerium,  a  metal  discovered  in  1803 
by  Berzelius,  and  named  after  the 
planet  Ceres.  It  is  brittle,  white, 
and  volatile  in  a  very  intense  heat : 
it  is  not  acted  upon  by  nitric  add, 
but  is  dissolved  in  aqua  regia,  nitro- 
hydrochloric  add 

Chain,  in  surveying,  is  a  lineal  mea- 
sure, consisting  of  a  certain  number 
of  iron  links,  usually  100,  serving 
to  take  the  dimensions  of  fidds,  &c.: 
at  every  tenth  link  is  usually  fas- 
tened a  small  brass  plate,  with  a 
figure  engraved  upon  it,  or  else  cut 
into  different  shapes,  to  show  how 
many  links  it  is  from  one  end  of 
the  chain 

Chains,  strong  links  or  plates  of  iron, 
the  lower  ends  of  which  are  bolted 
through  a  ship's  side  to  the  tim- 
bers 

Chain-plates,  plates  of  iron  bolted  to 
the  side  of  a  ship,  to  which  the 
chains  and  dead-eyes  of  the  lower 
rigging  are  connected 

Chain-pump,  an  hydraulic  machine  for 
raising  water.  It  is  made  of  dif- 
ferent lengths,  and  consists  of  two 
collateral  square  barrels  and  an 
endless  chain  of  pistons  of  the 
same  form,  fixed  at  proper  dis- 
tances 

Chttin-timber,iD.  brick-building,  a  tim- 
ber of  large  dimensions  placed  in 
the  middle  of  the  height  of  a  story, 
for  imparting  strength 

Chairs,  Andently,  in  most  apart- 
ments  we  find  "two  great  chayers :" 
these  were  arm-chairs,  vrith  stuffed 
backs  and  sides,  entirely  covered, 
and  similar  to  the  lounging-chairs 
of  the  present  day.  Others  are  de- 
scribed  as*  Flemish  chairs,'  *  scrolled 
chairs,' and '  turned  chairs,' wrought 
in  ebony,  walnut,  cherry-tree,  Ac., 
with  high  backs,  either  stuffed  in 


93 


CHA 


CHANTING. 


CHA 


one  long  upright  panel,  or  fiUed 
with  wicker-work,  &c. 

Chaieedonyt  a  precious  stone,  in  colour 
like  a  carbuncle;  by  some  translated 
from  the  Scriptures  as '  emerald' 

Chaleidieumf  among  the  Romans,  a 
large,  low,  and  deep  porch,  coTcred 
with  its  own  roof,  supported  on  pi- 
lasters, and  appended  to  the  en- 
trance-front of  a  building,  where  it 
protected  the  principal  doorway, 
and  formed  a  grand  entrance  to  the 
whole  edifice 

Chaleidria,  chambers  attached  to  a 
basilica ;  they  were  built  at  one  end 
when  the  situation  would  admit 
of  it 

ChaUeef  the  cup  used  for  the  wine  at 
the  celebration  of  the  Eucharist 

Chalk,  in  geology,  forms  the  higher 
part  of  the  series  or  group  termed 
cretaceous:  it  is  composed  of  nearly 
44  parts  of  carbonic  add  and  56 
parts  of  lime 

Chambert,  according  to  Palladio,  are 
made  either  arched  or  with  a  flat 
ceiling :  if  in  the  last  way,  the  height 
from  the  floor  to  the  joists  above 
ought  to  be  equal  to  their  breadth; 
and  the  chambers  of  the  second 
story  must  be  a  sixth  part  less  than 
them  in  height 

Chamfer,  An  edge  or  arris,  taken  off 
equally  on  the  two  sides  which  form 
it,  leaves  what  is  called  a  chamfer, 
or  a  chamfered  edge.  If  the  arris 
be  taken  off  more  on  one  side  than 
the  other,  it  is  said  to  be  splayed 
or  bevelled 

Chamfering,  the  process  of  cutting  the 
edge  or  the  end  of  any  thing  bevel 
or  aslope 

Champ,  the  flat  surface  of  a  wall 

Champe,  the  field  or  ground  on  which 
carving  is  raised 

Chan^  de  Mars  .•  in  French  history, 
the  public  assemblies  of  the  Franks 
are  said  to  have  been  held  in  an 
open  field,  and  in  the  month  of 
March ;  whence  the  name 

Chancel,  the  choir  or  eastern  part  of 
a  church  appropriated  to  the  use  of 
those  who  ofilciate  in  the  perform, 
ance  of  the  services,  and  separated 

94 


from  the  nave  and  other  portions 
in  which  the  congregation  assemble, 
sometimes  by  a  screen 

Channel,  in  hydrography,  the  deepest 
part  of  a  river,  luurbour,  or  strait, 
which  is  most  convenient  for  the 
track  of  shipping ;  also  an  arm  of 
the  sea  running  between  an  island 
and  the  main,  or  continent,  as  the 
British  Channel,  &c. 

Channels,  broad  pieces  of  plank  bolted 
edgewise  to  the  outside  of  a  vessel, 
used  for  spreading  the  lower  rigging 

Chant,  Chanting.  The  word  *  chant' 
is  derived  from  the  Latin  Canius, 
which  signifies  singing ;  a  song,  a 
tune,  or  melody, — ^the  sound  of  a 
trumpet,  crowing  of  a  cock  (whence 
this  bird  is  called  '  chanticleer'): 
it  also  signifies  the  frequent  repe- 
tition of  the  same  thing.  The  word 
chant  is  not  confined  to  merely  a 
melody  consisting  of  several  notes; 
it  may  consist  of  one  only  :  in  this 
case  it  is  called,  in  church  music, 
'  intonation,'  although  in  Gregorian 
music  the  word  intonation  has  a 
somewhat  different  signification. 
(See  Gregorian  Chant.)  Hence 
chanting  is  reciting  in  a  musical 
tone,  and  is  peculiarly  adapted  to 
a  dignified  utterance  of  the  sublime 
language  of  the  Liturgy.  Chant- 
ing  or  intoning  on  a  monotone,  or 
single  sound,  is  the  simplest  and 
easist  method  of  reading  and  re- 
spending  the  various  prayers,  ex- 
hortations,  litanies,  suffrages,  Kyrie 
eliesons,  Allelujahs,  Gloria  Patri, 
and  the  Amens,  and  is  eminently 
more  dignified  and  solemn  than 
when  there  is  neither  elevation  nor 
depression  of  the  voice  at  any  one 
termination.  In  chanting  the 
greater  and  lesser  Canticles, — ^the 
Te  Peum,  Jubilate,  Benedidte, 
Benedictus,  Athanasian  Creed,  Ve- 
nite  exultemus.  Magnificat,  Can- 
tate  Pomino,  Nunc  dimittis,  Deus 
misereatur,as  also  the  prose  Psalms, 
— ^the  chant  may  consist  of  more 
than  one  tone,  although  it  is  prefer- 
able  to  use  a  small  number.  The 
method  of  chanting  the  Psalter  in 


CHA 


CHEMISTRY. 


CHE 


the  English  church  is  different  from 
that  adopted  on  the  Continent,  where 
it  appears  to  be  governed  by  no 
role ;  whereas  the  Gregorian  chant 
is  governed  entirely  by  rule 

ChatUhie,  in  building,  a  piece  of  wood 
listened  nearthe  ends  of  the  rafters, 
and  projecting  beyond  the  wall,  to 
support  two  or  three  rows  of  tiles, 
so  placed  to  hinder  the  rain-water 
from  tpckling  down  the  sides  of 
the  walls 

Ckaniry,  an  ecclesiastical  benefice  or 
endowment  to  provide  for  the  chant- 
ing of  masses 

Chapelj  a  small  building  attached  an- 
dently  to  various  parts  of  large 
churches  or  cathedrals,  and  sepa- 
rately dedicated ;  also  a  detached 
building  for  divine  service:  in  Eng- 
land, chapels  are  sometimes  called 
eluqteU  of  eeue,  built  for  the  accom- 
modation of  an  increasing  popu- 
lation 

CS^^^w/Zin^,  wearing  a  ship  round,  when 
taken  aback,  yrithout  bracing  the 
head-yards 

Chapiter,  the  capital  of  a  column 

duplet,  in  architecture,  a  small  orna- 
ment carved  into  round  beads,  &c. 

Chapft  the  two  planes  or  flat  parts  of 
a  vice  or  pair  of  tongs  or  pliers,  for 
holding  any  thing  fast,  and  which 
are  generally  roughed  with  teeth 

ChapteT'house,  an  establishment  for 
Deans  and  Prebendaries  of  cathe- 
drals and  collegiate  churches ;  the 
apartment  or  hall  in  which  the 
monks  and  canons  of  a  monastic 
establishment  conduct  their  affairs 
connected  with  ecclesiastical  regu- 
lationa 

Char  or  Chare,  to  hew,  to  work 
charred  stone  ;  hewn  stone 

Character,  in  a  picture,  is  giving  to  the 
different  objects  their  appropriate 
and  distinguishing  appearance 

Charcoal  consists  mainly  of  carbon 
procured  from  the  decomposition 
of  wood  by  burning.  This  ope- 
ration is  generally  conducted  in 
pits  made  in  the  ground,  and  in 
iron  cylinders.  Wood  is  essentially 
composed  of  carbon,  oxygen,  and 


hydrogen.  Charcoal  has  the  same 
properties:  it  is  black,  lighter  than 
water,  and  full  of  pores,  occasioned 
by  the  expulsion  of  the  bodies  voliu 
tilized 

Charge,  in  electricity,  is  the  accumu- 
lation of  the  electric  matter  on  one 
surface  of  an  electric,  as  a  pane  of 
glass,  Leyden  phial,  &c.,  whilst  an 
equal  quantity  passes  off  from  the 
opposite  surface 

Charge,  in  mining:  any  quantity  of  ore 
put  at  one  time  into  a  furnace  to 
fuse  is  called  a  *  charge ;'  letting  it 
out  is  called  *  tapping' 

Chargers,  large  dishes,  sometimes  de- 
scribed as  *  flat  pieces ' 

Cheeks,  the  shears  or  bed  of  the  lathe 
as  made  with  two  pieces  for  con- 
ducting the  puppets 

Cheeks,  the  projection  on  each  side 
of  a  mast,  upon  which  the  trestle- 
trees  rest ;  the  sides  of  the  sheet 
of  a  block 

Cheerly,  quickly ;  with  a  will 

Chemistry,  The  science  of  chemistry 
has  for  its  object  the  study  of  the 
nature  and  properties  of  the  dif- 
ferent substances  of  which  the 
earth,  the  waters,  the  air,  and  their 
inhabitants,  (namely,  plants  and 

..  animals,)  are  composed.  In  a 
word,  it  embraces  the  study  of 
every,  thing  under  heav^i  accessible 
to  man.  In  its  highest  branches 
it  aims  at  discovering  the  laws  or 
rules  which  regulate  the  fonnation 
of  chemical  compoundr  generally ; 
and  in  its  useful  applift&tions  it  has 
been  already  exceedingly  service- 
able in  directing  and  improving 
the  various  arts  of  common  life,  as 
agriculture,  the  working  of  metals, 
dyeing,  and  many  other  pursuits. 
It  serves  also  to  guide  the  medical 
man  in  the  preparation  of  his  re- 
medies, and  also  occasionally  in 
distinguishing  between  diseases 
which  are  in  other  respects  much 
alike.  There  is,  indeed,  scarcely  a 
situation  in  life  in  which  a  know- 
ledge  of  chemistry  may  not  prove 
directly  useful.  It  is  a  science  the 
study  of  which,  from  its  simplest 


95 


CHE 


CHIMES. 


CHI 


.  beginnings  to  its  highest  attempts, ' 
is  rendered  delightful  by  the  con- 
stant sacoession  of  new  and  inter- 
esting things  brought  before  the 
eye  and  the  mind. 

Cherry'treef  a  hard,  close-grained 
wood,  of  a  pale  red-brown  colour : 
when  stained  with  lime,  and  oiled 
and  Tarnished,  it  resembles  maho- 
gany, and  is  used  for  furniture,  &c. 

CheU'treett  pieces  of  oak  fitted  to  the 
sides  of  a  vessel,  abaft  the  fore- 
chains,  with  a  sheave  in  them,  to 
board  the  main-tack  to ;  not  much 
used 

Chettf  a  piece  of  furniture  for  the  re- 
ception of  all  kinds  of  goods,  parti- 
cularly household  conYeniences,de- 
posited  therein  for  security,  and  for 
plate ;  placed  also  in  churches,  for 
the  keeping  of  the  holy  vessels,  vest- 
ments, &c.:  the  seaman's  chest  con- 
tains in  the  personalities  of  a  sailor. 
Coffers  and  chests  were  the 
general  repositories  for  articles  of 
every  kin4 ;  writings,  apparel,  food, 
and  even  fuel,  were  kept  within 
them.  Many  of  these  chests,  which 
were  raised  on  feet  to  protect  them 
from  damp  and  vermin,  were  beau- 
tiAiUy  ornamented  with  carving 
and  other  sumptuous  enrichments. 
Large  trunks,  in  which  clothes, 
hangings,  &c.,  were  packed  for 
removal,  were  called  'Trussing 
Chests:'  they  were  substantially 
made,  and  bound  in  every  direction 
with  ux)n  straps,  wrought  into  fan- 
ciful forms,  and  secured  by  locks 
of  artful  and  curious  contrivance. 
Two  "  standard  chests ''  were  de- 
livered to  the  laundress  of  King 
Henry  VIII. ;  "  the  one  to  keep  the 
deane  stuff,  and  the  other  to  keep 
the  stuff  that  had  been  occupied.'' 
"  In  ivory  coffers,"  says  Grameo,  "I 
have  stuffed  my  crowns ;  in  cypress 
chests,  my  arras,  counter-points, 
&c."  Cypress  wood  was  selected 
for  its  rare  properties  of  neither 
rotting  nor  becoming  worm-eaten. 

Chestnut  wood  is  very  durable,  and 
was  formerly  much  used  in  house 
carpentry  and  furniture 

96 


Chetal  de/ritet  a  square  or  octagonal 
beam  of  wood,  from  6  to  9  feet  in 
length,  and  pierced  by  iron  rods  or 
wooden  pickets  6  feet  long,  which 

-  are  pointed  at  each  end,  and  shod 
with  iron:  the  pickets  are  placed 
6  inches  asunder,  and  pass  through 
two  opposite  faces  of  the  heam,  in 
directions  alternatelyat  right  angles 
to  each  other,  the  cheval  resting  on 
the  ground  at  the  lower  extremity 
of  the  pickets 

Chevetf  the  termination  of  a  church 
behind  the  high  altar,  when  of  a 
semicircular  or  polygonal  form 

Chevrofif  a  moulding  of  a  zig-zag  cha- 
racter, of  the  Norman  style  parti- 
cularly, but  sometimes  to  he  found 
with  the  pointed  arch 

ChiarO'Oscuro,  a  drawing  made  in  two 
colours,  black  and  white ;  also  the 
art  of  advantageously  distributing 
the  lights  and  shadows  which  ought 
to  appear  in  a  picture,  as  well  for 
the  repose  and  satisfaction  of  the 
eye  as  for  the  effect  of  the  whole 
together 

ChiUadt  an  assemblage  of  several 
things  ranged  by  thousands;  appUed 
also  to  tables  of  logarithms,  -which 
were  at  first  divided  into  thou- 
sands 

Chiliaedron,  a  solid  figure  of  a  thou- 
sand faces 

CkUiagon,  in  geometry,  a  regular 
plane  figure  of  a  thousand  sides 
and  angles 

Chimett  a  set  of  bells  tuned  to  the 
modem  musical  scale,  and  struck 
by  hanuners  acted  on  by  a  pinned 
cylinder,  or  barrel,  which  revolves 
by  means  of  clock-work :  also  ap- 
plied to  the  music  or  tune  pro- 
duced by  mechanical  means  from 
the  bells  in  a  steeple,  tower,  or 
common  clock 

Chimney,  in  locomotive  engines.  The 
chimney  is  regulated  in  size  for 
each  engine  so  as  to  act  in  union 
with  the  blast-pipe,  to  produce  a 
proper  blast  on  the  .fire.  This  is 
done  by  each  exhaust  of  steam 
from  the  cylinders  creating  a  partial 
vacuum  in  the  chimney:  hence  a 


CHI 


CHISELS. 


CHI 


rush  of  air  takes  place  through  the 
fire  and  tubes  to  fill  this  mcuum ; 
and  these  successive  rushes  of  air 
*  blow  the  fire/  This  vacuum  ranges 
from  2  to  8  inches  of  a  water-gauge. 
The  mild  blast  produces  the  least 
vacuum  and  the  least  consumption 
of  fiiel 

CJamney-piecea.  The  Egyptians,  the 
Greeks,  and  the  Romans,  to  whom 
architecture  is  so  much  indebted  in 
other  respects,  living  in  warm  cli- 
mates, wher«  fires  in  the  apart- 
ments were  seldom  necessary,  have 
thrown  but  little  light  on  this  branch 
of  the  science.  Palladio  only  men- 
tions two  which  stood  in  the  mid- 
die  of  the  rooms,  and  consisted  of 
oohmms,  supporting  architraves, 
whereon  were  placed  the  pyramids 
or  funnels  through  which  the  smoke 
was  conveyed.  Scamozzi  mentions 
only  three  in  his  time,  placed  simi- 
larly.  In  England,  Inigo  Jones 
designed  some  very  elaborate  chim- 
ney-pieces. The  size  of  the  chim- 
ney must  depend  upon  the  dimen- 
sions of  the  room  wherein  it  is 
placed :  the  chimney  should  always 
be  situated  so  as  to  be  immediately 
seen  by  those  who  enter :  the  mid- 
dle of  the  side  partition  wall  is  the 
best  place  in  halls,  saloons,  and 
other  rooms  of  passage  to  which 
the  principal  entrances  are  com- 
monly in  the  middle  of  the  front  or 
of  the  back  wall ;  but  in  drawing- 
rooms,  dressing-rooms,  &c.,  the 
middle  of  the  back  wall  is  the  best 
situation  ;  the  chimney  being  then 
farthest  removed  from  the  doors  of 
communication 

Chinese  arcAt/^e/t(re,  a  style  peculiar  to 
China,  where  the  material  employed 
is  principally  wood.  It  is  a  style 
not  congenial  to  English  taste  or 
climate:  its  monstrosity  may  bfc 
seal  at  Brighton 

Chineae  Yellow  (colour),  a  very  bright 
snlphuret  of  arsenic,  brought  from 
China 

Chinse,  to  thrust  oakum  into  seams 
with  a  small  iron 

Chisel^  a  tool  with  the  lower  part  in 

^7" 


the^orm  of  a  wedge,  for  cutting 
iron  plate  or  bar,  and  with  the 
upper  part  flat,  to  receive  the  blows 
of  a  hammer,  in  order  to  force  the 
cutting  edge  through  the  substance 
of  the  iron 

Chisel,  an  instrument  used  by  car- 
penters.  The  large  chisels  used  by 
millwrights  for  heavy  work  are  ge- 
nerally composed  of  iron  an4  steel 
welded  together.  Chisels  are  also 
employed  in  turning,  and  they  are 
driven  more  or  less  by  blows :  those 
used  by  the  joiner  are  similar ;  but 
those  used  by  cabinet-makers  are 
straight  across  the  end 

Chisels  in  general  A  chisel  is  an 
edge  tool  for  cutting  wood,  either 
by  leaning  on  it  or  by  striking  it 
with  a  maUet.  The  lower  part  of  the 
chisel  is  the  frustrum  of  a  cuneus 
or  wedge ;  the  cutting  edge  is  al- 
ways on  and  generally  at  right 
angles  to  the  side,  "nie  basil  is 
ground  entirely  from  one  side. 
The  two  sides  taper  in  a  small  de- 
gree upwards,  but  the  two  narrow 
surfaces  taper  downwards  in  a 
greater  degree.  The  upper  part  of 
the  iron  has  a  shoulder,  which  is  a 
plane  surface  at  right  angles  to  the 
middle  line  of  the  chisel.  From 
this  plane  surface  rises  a  prong  in 
the  form  of  a  square  pyramid,  the 
middle  line  of  which  is  the  same  as 
the  middle  line  of  the  cuneus  or 
wedge :  the  prong  is  inserted  and 
fixed  in  a  socket  of  a  piece  oi  wood 
of  the  same  form:  this  piece  of 
wood  is  called  the  handle,  and  is 
generally  the  frustrum  of  an  octa- 
gonal pyramid,  the  middle  line  of 
which  is  the  same  as  that  of  the 
chisel:  the  tapering  sides  of  the 
handle  diminish  downwards,  and 
terminate  upwards  in  an  octagonal 
dome.  The  use  of  the  shoulder  is 
for  preventing  the  prong  from  split- 
ting the  handle  while  being  struck 
with  the  mallet.  The  chisel  is 
made  stronger  from  the  cutting 
edge  to  the  shoulder,  as  it  is  some- 
times used  as  a  lever,  the  prop 
being  at  or  very  near  the  middle, 


£ 


CHI 


CHOCOLATE  LEAD. 


CHO 


the  power  at  the  handle,  atid  the 
resistance  at  the  cutting-edge. 
Some  chisels  are  made  with  iron 
on  one  side  and  steel  on  the  other, 
and  others  consist  entirely  of 
steel.  There  are  several  kinds  of 
chisels,  as  the  mortise-chisel,  the 
ripping-chisel,  and  the  socket- 
chisel 

Chiseli  the  firmer ^  is  formed  in  the 
lower  part  ^milar  to  the  socket- 
cliisel;  but  each  of  the  edges  above 
the  prismoidal  part  falls  into  an 
equal  concavity,  and  diminishes 
upwards  until  the  substance  of  the 
metal  between  the  concave  narrow 
surfaces  becomes  equal  in  thickness 
to  the  substance  of  that  between 
the  other  two  sides,  produced  in  a 
straight  line,  and  meeting  a  protu- 
berance projecting  equally  on  each 
side.  The  firmer  chisel  is  used  by 
carpenters  and  joiners  in  cutting 
away  the  superfluous  wood  by  thin 
chips :  the  best  are  made  of  cast 
steel.  When  there  is  a  great  deal 
of  superfluous  wood  to  be  cut  away, 
sometimes  a  stronger  chisel,  consist- 
ing of  an  iron  back  and  steel  face, 
is  first  used,  by  driving  it  into  the 
wood  with  a  mallet;  and  then  a 
slighter  one,  consisting  entirely  of 
steel  sharpened  to  a  very  fine  edge, 
is  used  in  the  finish.  The  first 
used  is  called  a  firmer,  and  the  last 
a  paring  chisel,  in  the  application 
of  which  only  the  shoulder  or  hand 
is  employed  in  forcing  it  into  the 
wood 

ChiseU  the  mortiae^  is  made  exceed- 
ingly strong,  for  cutting  out  a 
rectangular  prismatic  cavity  across 
the  fibres,  quite  through  or  very 
deep  in  a  piece  of  wood,  for  the 
purpose  of  inserting  a  rectangular 
pin  of  the  same  form  on  the  end  of 
another  piece,  and  thereby  uniting 
the  two.  The  cavity  is  called  a 
mortise,  and  the  pin  inserted,  a 
tenon ;  and  the  chisel  used  for  cut- 
ting out  the  cavity  is,  therefore, 
called  a  mortise-chisel.  As  the 
thickness  of  this  chisel  from  the 
face  to  the  back  is  great,  in  order 

98 


to  withstand  the  percussive  force 
of  the  mallet,  and  as  the  angle 
which  the  basil  makes  with  the 
face  is  about  25°,  the  slant  dimen- 
sion of  the  basil  is  very  great.  This 
chisel  is  only  used  by  percassive 
force  given  by  the  mallet 

Chisel,  the  rippinfff  is  only  an  old 
socket-chisel  used  in  cutting  holes 
in  walls  for  inserting  plugs,  and  for 
separating  wood  that  has  been 
nailed  together,  &c. 

Chigelf  the  socket,  is  used  for  cutting 
excavations:   the  lower  part  is  a 
prismoid,  the  sides  of  which  taper 
in  a  smaU  degree  upwards,  and  the 
edges  considerably  downwards:  one 
side  consists  of  steel,  and  the  other 
of  iron.    The  under  end  is  ground 
into  the  form  of  a  wedge,  forming 
the  basil  on  the  iron  side,  and  the 
cutting  edge  on  the  lower  end  of 
the  steel  face.  From  the  upper  end 
of  the  prismoidal  part  rises   the 
frustrum  of  ahollowcone,  increasing 
in  diameter  upwards :  the  cavity  or 
socket  contains  a  handle  of  wood 
of  the  same  conic  form:  the  axis 
of  the  handle,  the  hollow  cone,  and 
the  middle  line  of  the  fhistnun,  are 
all  in  the  same  straight  line.     The 
socket-chisel,  which  is  commonly 
about  1^  or  1^  inch  broad,  is  chiefly 
used  in  cutting  mortises,  and  may 
be  said  to  be  the  same  as  the  mor- 
tise-chisel employed  in  joinery 

Chiselt  in  turnery,  a  flat  tool,  skewed 
in  a  small  degree  at  the  end,  and 
bevelled  from  each  side,  so  as  to 
make  the  cutting  edge  in  the  mid- 
dle of  its  thickness 

Chock,  in  navigation,  a  wedge  used  to 
secure  any  thing  with,  or  for  any 
thing  to  rest  upon.  The  long-boat 
rests  upon  two  large  chocks  when 
it  is  stowed 

Chocolate  lead,  a  pigment  prepared 
by  calcinating  oxide  of  lead  with 
about  a  third  of  that  of  copper, 
and  reducing  the  compound  to  a 
uniform  tint  by  levigation 

Choke,  An  adit  is  said  to  be  choked 
when  any  earth  or  stone  falls  in 
and  prevents  the  current  of  water 


I" 


CHO 


CHRON0METRICAL  GOVERNOR. 


CHR 


through  it :  the  place  or  part  so 
fiUed  is  called  <the  choke ' 

Chopping  block,  a  block  of  wood  used 
for  reducing  bricks  totheir  intended 
form  by  axing  them :  it  is  made  of 
any  chance  piece  that  can  be  ob- 
tained, and  commonly  from  6  to  8 
inches  sqnare,  supported  generally 
upon  two  14-iDch  brick  piers,  if  two 
men  are  to  work  at  it ;  but  if  four 
men,  the  cfaopping-block  must  be 
lengthened  and  supported  by  three 
piers,  and  so  on,  according  to  the 
number :  it  is  about  2  feet  3  inches 
in  hdgfat 

Choragie  monwneniSf  in  Grecian  story, 
monuments  in  honouv^  of  those 
who  bad  gained  a  prize  as  cboragus, 
or  leader  of  the  play  and  choruses 

Choragie  monament  (the)  of  Lysicra- 
tes,  known  as  the  Lantern  of  De- 
mosthenes, was  built  in  the  111th 
Olympiad,  and  is  stiU  entire :  it  is 
considered  the  most  exquisite  and 
perfect  specimen  of  the  orders 

Ckoragic  monument  of  Thrasycles^  &c., 
now  the  church  of  our  Lady  of  the 
Grotto.  It  is  built  against  the  rock 
of  the  Acropolis:  above  it  stand 
two  columns,  on  which  tripods  have 
been  placed,  and  on  each  side  of 
it  the  rock  has  been  chiseled  away 
in  such  form  as  evidently  shows 
that  similar  buildings  had  been 
erected  contiguous  to  it 

Chords  in  geometry,  is  the  right  line 
joining  the  extremities  of  any  arc 
of  a  circle 

Chorobates  (Greek),  an  instrument 
for  determining  the  slope  of  an 
aqueduct,  and  the  levels  of  the 
country  through  which  it  was  to 
pass.  It  differed  but  slightly  from 
a  common  carpenter's  level,  which 
consists  of  a  straight  rule  support- 
ing a  perpendicular  piece,  against 
wMch  bangs  a  plumb-line 

Chorographyt  the  art  of  making  a  map 
of  a  particular  country  or  province, 
or  of  teaching  geography 

Chromatics,  a  division  of  the  science 
of  optics,  by  which  the  properties 
of  the  colours  of  light  and  of  na- 
tural bodies  are  illustrated 


Chromascopet  or  optical  chromatics : 
there  are  three  species  of  optical 
effects  of  colours, — that  of  refrac- 
tion of  prisms  and  lenses,  that  of 
the  transmission  of  light  through 
transparent  media,  and  that  of  the 
reflection  of  specula,  &c. 

Chromate  of  mercury  is  improperly 
classed  as  a  red  with  vermillion ; 
for  though  it  is  of  a  Vight  ochreous 
red  colour  in  powder,  it  is,  when 
ground,  of  a  bright  orange  ochre 
hue,  and  affords,  with  white,  very 
pure  orange-coloured  tints 

Chromatics,  the  science  of  the  rela- 
tions of  light,  shade,  and  colours 

Chrome  greens  are  compound  pig- 
ments of  which  chrome  yellow  is 
the  principal  colouring  substance 

Chrome  orange  is  a  beautiful  orange 
pigment,  and  one  of  the  most 
durable  and  least  exceptionable 
chromates  of  lead,  but  not  of  iron 

Chrome  yellow  is  a  pigment  of  modem 
introduction  into  general  use,  and 
of  which  there  are  many  varieties, 
mostly  chromates  of  lead,  in  which 
thelattermetalmore  or  less  abounds. 
They  are  distinguished  by  the  pure- 
ness,  beauty,  and  brilliancy  of  their 
colours,  which  qualities  are  great 
temptations  to  their  use  in  the 
hands  of  the  painter;  they  are, 
however,  far  from  unexceptionable 
pigments 

Chromium,  a  very  rare  metal,  found 
either  in  the  form  of  chromate  of 
lead  or  chromate  of  iron 

Chronometer,  a  time-keeper,  used  for 
determining  the  longitude  at  sea, 
and  for  other  purposes  where  great 
accuracy  is  required 

Chronometrical governor,  an  improved 
regulator  for  rendering  the  mean 
velocity  of  an  engine  umform.  The 
mechanism  is  as  follows :  a  spindle 
placed  vertically  has  a  pulley  fixed 
upon  the  top,  to  receive  motion  from 
the  crank-shaft ;  below  the  pulley 
two  bevel-wheels  of  equal  diameters 
are  placed  face  to  face ;  the  upper 
wheel  is  fixed  to  the  spindle,  and 
the  lower  one  is  free  to  turn  upon 
it,  and  has  an  arm  or  crank  attached 


99 


CHR 


CHURCH  MUSIC. 


CHU 


to  its  under  aidei  to  act  as  a  driver 
for  the  pendulous  ball :  between  the 
two  wheels,  and  communicating 
with  them,  is  a  third  wheel,  fixed 
upon  a  spindle  placed  horizontally, 
and  connected  at  one  end  to  the 
vertical  spindle,  so  as  to  turn  round 
it;  the  other  end  is  supported  by  a 
carriage  resting  upon  a  plate^  and 
is  connected  to  a  spring  or  counter- 
weight on  one  side,  and  on  the 
other  side  to  the  throttle-valve; 
the  ball  being  suspended  from  a 
spherical  bearing  near  the  top  of 
the  rod.  The  spring  ig  adjusted 
so  that  when  the  velocity  of  the 
engine  is  as  required,  the  upper  and 
lower  wheels  revolve  at  the  same 
speed :  when  the  velocity  increases, 
the  centrifugal  force  causes  the  ball 
to  rise,  and  retards  the  motion  of 
the  lower  wheel;  then  the  inter- 
mediate wheel  distends  the  spring, 
and  moves  forward  upon  the  lower 
wheel  as  a  rack,  and  closes  the 
throttle-valve:  when  the  velocity 
diminishes,  the  ball  faUs,  and  the 
lower  wheel  requires  less  power,  so 
that  the  spring  pulls  back  the  inter- 
mediate wheel  and  opens  the  valve. 
The  above  is  a  modification  of  Mr. 
James  Wood's  governor,  and  is  pa- 
tented by  Mr.  C.  W.  Siemans 

ChryfolitCj  a  precious  stone,  probably 
the  tenth  on  the  high  priest's  pec- 
toral, bearing  the  name  of  Zebulon: 
it  i^  transparent,  the  colour  of  gold, 
with  a  mixture  of  green,  which  dis- 
plays a  fine  lustre 

Chucky  a  piece  of  wood  or  metal  fixed 
on  tiie  end  of  the  mandril  for  keep- 
ing fast  the  >body  to  be  turned 

Cpurch  Music,  By  this  term  is  com- 
monly imderstood  aU  music  set  to 
words  of  a  sacred  character:  hence 
we  have  not  only  the  language  of 
Scripture  set  to  music  in  the  shape 
of  anthems,  &c.,  but  also  metrical 
versions  and  paraphrases  thereof, 
used  and  considered  by  many  as 
church  music.  Indeed  it  too  often 
happens  that  these  are  adapted  to 
secular  melodies — ^melodies  not  ori- 
ginally intended  to  be  applied  to 


■'■ » 


words  of  a  sacred  character*  and  yet 
the  music  is  then  termed  sacred, 
probably  irom  an  idea  that  tliere  is 
no  such  thing  as  sacred  and  profane 
music.  But  this  is  a  great  error, 
and  arises  solely  from  ignorance  of 
the  existence  of  sacred  muuc, — ^we 
mean  especially  church  music  Ex- 
amine any  of  the  ancient  authorized 
liturgical  books,  and  tiiere  will  be 
found  an  order  of  music  that  can- 
not be  mistaken  for  profane»  which 
is  not  only  sacred  in  its  character, 
but  eminently  grand,  dignified, 
noble,  and  sublime ;  in  short,  it  is 
for  church  purposes  so  superior  to 
all  other  music,  that  it  alone  can 
properly  be  called  church  music. 

Church  music  is  the  music  of  the 
holy  offices, — is  that  music  in  which 
the  whole  cAurcA,  priests  and  people, 
can  participate.  It  is  easy  to  exe- 
cute, being  simple  and  pkdn  (plain 
chant).  It  can  he  sung  by  every 
one,  and  is  always  most  majestic 
when  sung  by  all;  hence  it  is  also 
called  the  fall  chant  (cantus  ple- 
nus).  For  a  long  period,  and  until 
very  lately,  scarcely  a  remnant  oj 
church  music  was  to  be  found,  even 
in  those  places  where  we  had  a 
right  to  expect  to  find  it :  the  plain 
chant  was  banished  entirely  in  some 
places,  and  mutilated  in  others,  so 
that  it  could  scarcely  be  discerned; 
but  it  is  now  being  restored,  and 
we  hear  the  priest  intoning  his  part 
in  the  offices  of  morning  and  evening 
prayer,  and  the  people  singing,  in 
response,  the  ancient  authorized 
melodies  of  the  church  'i — we  heai 
the  Psalter  chanted  to  fine  old  (so 
called)  Gregorian  tones ; — ^we  heai 
the  Litany  chanted  to  its  ownpropei 
music,  that  of  the  church :  we  also 
hear  the  soul-stirring  music  in  the 
Communion  office,  the  Gloria  in  ex- 
celsis,  the  Credo,  andSanctus;  the 
latter  moreover  in  its  proper  pl|ice< 
We  can  have  also,  if  so  disposed, 
the  church  music  for  the  matrix 
monial,baptismal,  and  burial  offices, 
as  well  as  an  immense  variety  oj 
tunes  for  the  metrical  psalms,  of  a 


100 


CHU 


CIRCLE. 


CIN 


true  dnureh  character,  unlike  any 
other  kind  of  music,  and  whieh  is 
tmly  chnrdi  music,  inasmuch  as  it 
is  the  church's  peculiar  property, 
md  wouM  be  totally  misused  in 
any  other  place.  Our  definition  of 
church  music  is,  music  which  is 
ad^ted  for  the  services  and  pur- 
poses of  the  church,  and  unfit  for 
any  other  place  or  purpose. 

Church  mittie,  such  as  is  here 
shortly  defined,  is  unisonous;  and 
harmmiized  music  is  not  fit  for 
congregational  purposes;  it  is  pro- 
per only  in  those  parts  of  divine 
worship  which  may  be  called  extra- 
UtnrgieEd,  such  as  the  anthem. 
Singing  harmonized  chants,  canti- 
cles, Te  Deum,  &c.,  is  thrusting  out 
Ihe  congregation,  that  is,  the  chief 
part  of  the  church  present.  Tlie 
harmonies  should  be  1^  entirely 
to  the  Ascretion  of  an  intelligent 
organist,  to  be  executed  on  the 
organ  alone.  Harmonized  music 
leqmres  accomplished  and  well- 
informed  musicians  for  its  perform* 
ance,  and  can  be  sung  only  by  the 
few.  The  anthem,  in  cathedral 
worship,  is  edifying  only  when  it  is 
performed  by  the  choir-men  in  a 
masterly  manner,  not  only  with 
correct  musical  execution,  but  with 
care  and  attention,  to  develop  all 
the  piety,  sublimity,  grandeur,  dig- 
nity, and  whatever  else  the  music 
is  capable  ai* 

Before  the  latter  half  of  the  15th 
century,  the  liturgy  was  chanted  in 
muson ;  and  it  is  from  this  period 
we  can  trace  the  gradual  departure 
fiom  the  rigid  church  style  of  music, 
in  the  compositions  of  Josquin  de 
Pr^  especially.  In  the  early  part 
of  the  16th  century,  we  find  that 
Adrian  Wilhert,  who  was  made  sing- 
ing-master at  St.  Mark's,  Venice, 
was  the  first  who  harmonized  the 
psalm  melodies  for  two  or  more 
choirs;  then  followed  the  motet,  or 
hannonized  antiphon,  which  before 
had  been  chanted  in  unison,  as  it 
is  done  at  this  day  in  the  Romish 
chapels  in  England,  where  there 

101 


are  not  accomplished  singing  men 
to  perform  the  motet.  During  this 
century,  the  use  of  harmony  had 
not  only  driven  the  people  away 
from  their  part  in  the  performance 
of  the  service,  but  also  corrupted 
the  music  itself  so  much,  that  it 
was  only  saved  from  being  wholly 
forbidden  by  the  grave  and  devo- 
tional motets  and  other  compo- 
sitions of  the  renowned  Palestrina, 
whose  works  were  imitated  with 
great  success  by  the  disciples  of  his 
school,  and  this  in  a  very  eminent 
degree  by  the  English  church  mu- 
sicians. The  harmonies  used  by 
Tallis,  Morley,  Gibbons,  and  the 
rest  of  the  masters  of  church  music 
of  this  age,  are  tmly  sublime 

Church  ornament  consists  principally 
of  the  painted  and  stained  glass 
windovrs  of  the  emblem  of  the 
Trinity,  of  the  passion  of  our  Lord, 
of  the  evangelists,  sacred  mono- 
grams, statues  of  the  holy  apostles, 
of  the  holy  evangelists,  and  of  the 
sttnts  commemorated  by  the  church 

Chmreh  in  rotunda,  that  whose  plan 
is  a  perfect  circle,  in  imitation  of  the 
Pantheon 

Chymolf  a  hinge,  anciently  called  a 
grimmer 

Ciboriumf  an  arch  supported  by  four 
pillars  placed  over  the  high  adtar 

CUeryy  in  architecture,  the  drapery  or 
leavage  that  is  wrought  upon  the 
heads  of  pillars 

Ctmellare,  the  vestry  or  room"^  where 
plate,  vestments,  and  other  rich 
things  belonging  to  the  church  are 
kept 

Cmciure,  a  ring,  list,  or  fillet  at  the 
top  and  bottom  of  a  column,  serving 
to  divide  the  shaft  from  the  capi- 
tal and  its  base 

Cinder-framej  in  locomotive  engines, 
a  wire-work  frame  placed  in  fh>nt 
of  the  tubes,  to  arrest  the  ascent  of 
large  pieces  of  ignited  coke 

Cinque-foily  an  ornamental  foliation  or 
feathering,  used  in  the  arches  of 
the  lights  and  tracery  of  windovirs, 
panellings,  &c. 

Cinque  Porta,  the  sea-port  tovms  of 


CIP 


CITRINE  COLOUR. 


CIT 


Dover,  Sandwich,  Hastings,  Hythe, 
and  Romney,  to  which  three  others 
were  afterwards  added,  viz.  Win- 
chelsea,  Rye,  and  Seaford.  These 
towns  possess  peculiar  privileges, 
and  are  under  the  government  of  a 
Lord  Warden 

Cipher  J  a  secret  mode  of  writing 

Cippua  (Latin),  a  low  column,  some- 
times round,  but  more  frequently 
rectangular,  used  as  a  sepulchnd 
monument 

CircinuSf  a  pair  of  compasses.  Those 
used  by  statuaries,  architects,  ma- 
sons, carpenters,  &c.,  were  often 
represented  on  their  tombs 

Circinug,  according  to  Vitruvius,  a  pair 
of  compasses  employed  by  archi- 
tects, carpenters,  &c.,  for  describing 
circles,  measuring  distances,  and 
taking  the  thickness  of  solids 

Circlet  a  plain  figure  contained  by 
one  line,  which  is  called  the  dr- 
cumference,  and  is  such  that  all 
straight  lines  drawn  from  a  certain 
point  within  the  figure  to  the  cir- 

.  cumference  are  equal  to  one  another, 
and  this  point  is  called  the  centre 
of  the  circle 

The  circumference  of  a  circle  is 
known  to  be  about  3*14159  times 
its  diameter,  or,  in  other  words, 
the  ratio  of  the  circumference  to 
the  diameter  is  represented  by 
3*14159 :  for  this  number  writers 
generally  put  the  Greek  letter  n- 

Circular  saw.  Cu*cular  saws,  revolv- 
ing uponan  axis,have  the  advantage 
that  they  act  continually  in  the 
same  direction,  and  no  force  is  lost 
by  a  backward  stroke:  they  are 
aiso  susceptible  of  much  greater  ve- 
locity than  the  reciprocating  saws, 
an  advantage  which  enables  them 
to  cut  more  smoothly :  used  prin- 
cipally for  cutting  mahogany  for 
veneering,  and  for  other  woods  cut 
into  thin  layers 

Circus,  an  area  used  by  the  Romans 
for  chariot-races  and  horse-races, 
and  for  other  public  sports 

Cissoid  of  Diodes,  in  the  higher  geo- 
metry, a  curve  line  of  the  second 
order 


Cistern.  There  were  cisterns  through- 
out  Palestine,  in  cities  and  in  pri- 
vate houses.  As  the  cities  were 
mostly  built  on  mountains,  and  the 
rains  fall  in  Judea  at  two  seasons 
only  (spring  and  autumn),  people 
were  obliged  to  keep  water  in  ves- 
sels. There  are  cisterns  of  very  large 
dimensions  at  this  day  in  Palestine. 
Near  Bethlehem  are  the  cisterns  oi 
pools  of  Solomon :  they  are  three 
in  number,  situated  in  the  sloping 
hollow  of  a  mountain,  one  above 
another,  so  that  the  waters  of  the 
uppermost  descend  into  the  second, 
and  those  of  the  second  descend 
into  the  third.  Thebreadthis  neark 
the  same  in  all,  between  80  and  90 
paces,  but  the  length  varies:  the 
first  is  about  160  paces  long ;  the 
second,  200;  the  third,  220.  These 
pools  formerly  supplied  the  town 
of  Bethlehem  and  the  city  of  Jeru- 
salem with  water.  Wells  and  cis- 
terns, fountains  and  springs,  are  sel- 
dom correctly  described  in  Scripture 

Cistern,  in  the  steam  engine,  the  ves- 
sel which  surrounds  the  condenser, 
and  contains  the  injection  water 

Cistema,  an  artificial  tank  or  reser- 
vou*,  sunkinthe  ground  and  covered 
in  with  a  roof,  for  the  p^irpose  oi 
collecting  andpreserving  goodwatei 
for  the  use  of  a  househcdd.  Neai 
the  baths  of  Titus  are  nine  subter- 
raneous cisterns,  17i  feet  wide,  12 
feet  high,  and  above  137  feet  long 

Citrine,  or  the  colour  of  the  dtron, 
is  the  first  oi  the  tertiary  class  oi 
colours,  or  ultimate  compounds  oi 
the  primary  triad,  yellow,  red,  and 
blue,  in  which  yellow  is  the  archeus 
or  predominating  colour,  and  blue 
the  extreme  subordinate;  for  ci- 
trine being  an  immediate  compound 
of  the  secondaries,  oiange  and 
green,  of  both  which  yellow  is  a 
constituent,  the  latter  colour  is  of 
double  occurrence  therein,  virhile 
the  other  two  primaries  ent^  singly 
into  the  composition  of  dtrine ;  its 
mean  or  middle  hue  comprehending 
eight  blue,  five  red,  and  six  yellow, 
of  equal  intensities 


^«*^ip— ^^ 


■^^^PW^P^I^^ 


102 


CLA 


CLASSIC  ORDERS. 


CLI 


atrme  iaJte  is  a  durable  and  better 
drying  species  of  brown  pink,  pre- 
pared from  the  quercitron  bark 

Ckiei,  the  valve  of  a  pump  piston ; 
the  can-lead,  in  DerbysHire 

Claeis,  in  locomotive  engines,  the 
complete  valves  of  the  pumps  where 
the  ball-Talve  is  enclosed  in  a  frame 
or  cage,  to  limit  its  rise,  and  guide 
its  fall  into  the  steam-tight  seat  of 
the  orifice  of  the  pipe 

Qaci'bojF,  in  locomotive  engines,  the 
box  fitted  on  to  the  boiler  where 
&  ball-clack  is  placed,  to  close  the 
orifice  of  the  feed-pipe,  and  pre- 
vent steam  or  hot  water  reaching 
the  pomps.  The  ball  of  the  clack 
is  raised  from  its  seat  by  the  stroke 
of  the  pump-plunger  forcing  the 
water  against  it,  and  which  water 
then  passes  into  the  boiler,  while 
the  instant  fall  of  the^Mdl  prevents 
egress  from  the  boiler 

CUet-door,  a  square ironplate  screwed 
on  to  the  side  of  a  bottom-pump, 
or  small  bore  for  convenience. of 
changing  the  clack  or  valve 

Oack'Beats,  in  locomotive  engines, 
two  recesses  in  each  pump,  for  the 
dacka  to  fit  into 

Claek'Vaive^  in  the  steam  engine,  a 
•flat  valve  in  the  cold-water  pump, 
with  a  hinge  joint 

Qanqt,  a  kiln  built  above  the  ground, 
for  the  purpose  of  burning  bricks  in 

Clamp,  a  piece  of  wood  fixed  to  the 

>•  end  of  a  board  by  mortise  and  tenon, 
or  by  groove  and  tongue,  so  that 
the  fibres  of  the  one  piece,  thus 
fixed,  traverse  those  of  the  board, 
and  by  this  means  prevent  it  from 
casting:  the  piece  at  the  end  is 
called  a  damp,  and  the  board  is 
said  to  be  clamped 

Clan^,  in  naval  architecture,  thick 
planks  in  a  ship's  side,  which  sup- 
port the  ends  of  the  beams 

Clan^nnfff  in  joinery,:  when  a  piece 
of  board  is  fitted  with  the  grain  to 
the  end  of  another  piece  of  board 
across  the  grain,  the  first  board  is 
said  to  be  clamped 

Clamp-nails,  used  to  fasten  on  clamps 
in  the  building  of  ships 

103 


Clatsie  orderSf  in  architecture:  of 
these  there  are  but  threet — the 
Doric,  Ionic,  and  Corinthian  :  two 
others,  the  Tuscan  and  Composite, 
are  often  improperly  classed  with 
liiem,  and  the  whole  denominated 
*the  five  orders  of  architecture.'  For 
the  prtqwrtiona  of  the  respective 
orders,  see  the  Synopsis,  p.  26 

Cleadinfftm  locomotive  engines,i8  usu- 
ally made  of  narrow  strips  of  tim- 
ber, neatly  fitted  round  the  boiler 
and  fire-box,  to  prevent  the  radi- 
ation of  the  heat.  Externally,  this 
is  sometimes  covered  with  zinc,  and 
a  coating  of  dry  hair  felt  is  com- 
monly placed  between-  the  boiler 
andthetimber,  for  the  same  purpose 

Clearing  the  deads,  a  term  for  clearing 
a  sht^  or  drift,  &c. 

Cleat,  a  piece  of  wood  used  in  different 
parts  of  a  vessel  to  belay  ropes  to 

Qeavage,  in  geology,  is  an  indicator  of 
pecuUar  fossility  in  certain  rocks, 
which  is  independent  of,  and  meets 
at  a  considerable  angle,  the  surfaces 
of  lamination  or  deposition.  Clay 
slate  furnishes  the  best  examples 
of  this  phenomenon 

Cleithralf  a  covered  Greek  temple 

CleithroSf  an  enclosed  place;  a  temple 
whose  loof  covers  or  encloses  it 

Clerestory,  an  upper  story  or  row  of 
windows  in  a  Gothic  church,  rising 
clear  above  the  adjoining  parts  of 
the  building 

Clew,  the  lower  comer  of  square-sails, 
and  the  after  comer  of  a  fore-and- 
aft  sail 

Clew-garnet,  a  rope  for  hauling  up  the 
clew  of  a  fore-sail  or  main-sail  in  a 
square-rigged  vessel 

CleW'Une,  a  rope  for  hauling  up  the 
clew  of  a  square-sail:  the  dew- 
gamite  is  the  clew-line  of  a  course 

Clicket,  a  latch-key;  the  latch  of  a  door 

Clinch,  in  navigation,  the  great  ring 
connected  with  the  mooring-chains 

Clinch,  a  half- hitch  stopped  to  its 
own  part 

CHnker-bar,  in  steam  engines,  the  bar 
fixed  across  the  top  of  the  ash-pit 
for  supporting  the  rods  used  for 
clearing  the  fire-bars 


CLI 


COAL. 


COA 


ClinJtertf  bricks  which,  by  the  vio- 
lence of  the  fire,  are  run  together 
and  glazed  over 
Clmkerst  hard  bricks  imported  from 

HoUand 
CloaeOf  a  common  sewer.    The  term 
cloaca  is  generally  used  in  reference 
to  those    spacious    subterraneous 
vaults,  either  of  stone  or  brick, 
through  which  the  foul  waters  of 
the  city,  as  weU  as  all  the  streams 
.   brought  to  Rome  by  the  aqueducts, 
finally  discharged  themselves  into 
the  Tiber 
Cloaca,  according  to  Livy,  a  large 
subterraneous  canal,  constructed  of 
masonry  or  brick- work,  for  the  pur- 
pose of  carrying  off  the  rain-water 
from  the  streets  of  a  town,  and 
the  impurities  from  private  houses, 
which  were  thus  discharged  into 
some  neighbouring  river 
Cloacarmm,  the  sewers'  rate;  a  tax 
which  was  levied  in  Rome  for  the 
expenses  of  deansing  and  repairing 
the  sewers 
Cloister,  a  covered  ambulatory,  fcmn- 
ing  part  of  a  monastic  or  collegiate 
establishment.  Cloisters  are  always 
attached  to  a  college  cathedral, 
and  arranged  round  three  or  four 
sides  of  a  quadrangular  area,  with 
large  windows,  not  often  glaased, 
looking  into  the  quadrangle 
Close-hauled,  a  term  applied  to  a  vessel 
sailing  with  her  yards  braced  up 
so  as  to  get  as -much  as  possible  to 
windward 
Closer,  a  brick-back  inserted  where 
the  distance  wiU  not  permit  of  a 
brick  in  length 
Closet,  a  small  chamber  or  private 

room 
CUme-hiteh,  two  half-hitches  round  a 

spar  or  other  rope 
Clove-hook,  an  iron  clasp,  in  two  parts, 
moving  upon  the  same  pivot  and 
overlapping  one  another,  used  for 
bending  chain-sheets  to  the  clews 
of  sails 
Clubbing,  drifting  down  a  current  with 

an  anchor  out 
Club'haul,  to  bring  a  vessel's  head 
round  on  the  other  tack,  by  letting 

104 


go  the  lee  anchor,  and  cutting  or 
slipping  the  cable 

due-garnets,  in  navigation,  tackles 
fixed  to  the  clews  or  lower  corners 
of  the  fore  and  main  sail,  to  dew 
them  up  to  the  yards.  (See  Clew- 
garnet.) 

Clustered  cohmm,  a  pier  which  con- 
sists of  several  columns  or  shafts 
clustered  together 

Clutch,  an  apparatus  for  engaging  or 
disengaging  two  shafts :  it  consists 
of  two  pieces  of  metal  formed  so 
that  when  placed  together,  project- 
ing pieces  on  one  (which  is  made  to 
slide  to  andfro  on  the  shaft,  but  turn 
with  it)  fit  into  recesses  in  the  other, 
which  is  fixed  on  the  driving  shaft, 
so  that  the  first  being  puUed  back, 
its  shaft  will  remain  at  rest 

Cooking,  in  ship -buildings  uniting 
pieces  of  spar  by  means  of  tabular 
projections,  formed  by  cutting  away 
the  solid  of  one  piece  into  a  hollow, 
so  as  to  make  a  projection  in  the 
other  in  such  a  manner  that  they 
may  correctly  fit,  the  buts  pre- 
venting the  pieces  from  drawing 
asunder 

Coal  belongs  to  the  third  series  of 
the  Wemerian  prindple,  vis.,  car- 
boniferous rocks,  coal  measures, 
carboniferous  limestone,  and  old 
red  sandstone  $  it  is  admitted  to  be 
of  vegetable  origin,  and  comprises — 
1.  Lignites,  aspedesofmineralchar- 
coal  or  intermediate  gradation  from 
wood  to  eoal;  2.  Ordinary  bitu- 
minous coal,  of  numerous  varieties; 
3.  Anthrarite,  found  generally  in 
connection  with  the  lowest  portion 
of  the  third  series,  and  sometimes 
in  the  primary  rocks  themselves. 
Coal,  then,  appears  to  have  been 
formed  of  large  vegetable  masses, 
of  considerable  extent,  in  strata 
varying  from  a  few  inches  to  many 
feet  in  depth,  the  strata  alter- 
nating with  rocks  wonderfully  uni- 
form, and  which  consist,  in  most 
eases,  of  the  fallowing :  sandstone, 
slate  clay  or  shale,  fire-clay,  iron- 
stone, limestone,  &c.  Rocks  are 
found  participating  of  both  day 


COA 


COCOA  WOOD. 


COC 


and  sandstone  text««,  greatly  pre- 
dominating. The  coal  beds  arc 
indiscriminately  accompanied  by 
locks  cither  of  san^tonc  or  shale, 
which  often  reat  upon  fire-clay.  It 
is  in  the  shale  accompanying  the 
coal  that  the  foasil  impressions  are 
80  numerous;  for  they  are  seldom 
foraid  in  the  sandstones,  or  in  the 
shales  considerably  distant  from  the 
coal  beds.  The  organic  remains  of 
coal  formation  consist  of  many 
shells  of  ftesh-water  origin.  The 
fossils,  with  land  pUmts,  occur  in 
great  abundance  and  Taricty,  be- 
longing to  extinct  species,  but 
bearing  considerable  analogy  to 
those  now  growing  only  in  tropical 
climates.  These  plants  are  mostly 
succulent,    and   are  of  enormous 

Coal-gag.  Carbnretted  hydrogen,  coaV 
jas  when  freed  from  the  obnoxious 
forign  gas,  may  be  propelled  in 
streams  out  of  small  apertures, 
which,  when  lighted,  form  jets  of 
flame,  and  are  caUcd  gas-lights 

Coal-tar ^  tax  made  from  bitummous 

ONmitiMV,  in  ships,  raised  ¥rork  nwnd 
theSitches,  to  prevent  water  from 
setting  down  into  the  hold 

CwU  Mast-coat  is  a  piece  of  canvas 
tarred  or  painted,  placed  round  a 
mast  or  bowsprit  where  it  enters 

the  deck 
Coat  m  buUding,  a  stratum  or  thich- 
niis  of  phister-work 

Cob  (Cornish),  to  ^«fk  o'^^f 
a  cobber,  a  bruiser  of  tm.  Cobbed 

ore  is  spotted  which  is  broken  out  of 
the  soKd  large  stones  with  sledges, 
and  not  put  to  water,  bemg  the 
best  ore  :  the  same  as  bingore  in 
the  lead  mines 
QoigM     The  ancient  name  for  tnis 
mineral  ig  not  known.  Theophrastus 
mentions  its  use  for  stainmg  gUiss. 
No  cobalt  has  been  discovered  in 
any  oi  the  remains  of  ancient  paint- 
ing.    It  makes  a  colour,  according 
to  Vitruvius,  between  scarlet  and 

C^^^  hi  chemistry,  a  metal,  when 


pure,  of  a  white  colour,  inclining 
to  bluish  or  steel  gray :  at  the  com- 
mon temperature  its  specific  gravity 
is  more  than  8*5 

Codalt-blue  is  the  name  now  appro- 
priated to  the  modem  improved 
blue  prepared  with  metallic  cobalt, 
or  its  oxides,  although  it  propo^ly 
belongs  to  a  class  of  pigments  in- 
cluding Saxon  blue,  Dutch  ultra- 
marine, Thenard's  blue,  royal  blue, 
Hungary  bine,  smalt,  Zaffoe  or 
enamel  blue,  and  Dumont's  blue. 
These  differ  principally  in  their 
degrees  of  purity,  firom  the  nature 
of  the  earUis  with  which  they  are 
compounded 

CobaU-green.  There  are  two  pig- 
ments of  this  denomination,  the 
one  a  compound  of  cobalt-blue  and 
chromic  yellow,  which  partakes  of 
the  qualities  of  those  pigments,  and 
may  be  formed  on  the  palette 

Coboose,  the  place  where  the  victuals 
are  cooked  on  board  of  merchant 
and  passenger  ships 

Cob  wail,  a  wall  built  of  unbumt  clay 
mixed  with  straw 

Cochineal  is  extremely  rich  in  the 
finest  red  colouring  matter,  and  has 
been  long  employed  in  scarlet  dye- 
ing, and  in  the  manufacture  of 
carmine 

CoehleOj  a  term  used  by  the  ancients 
to  denote  something  of  a  spiral 
form;  a  spiral  pump  for  raising 
water,  &c. 

Cock,  or  stop-cock,  a  kind  of  valve 
contrived  for  the  purpose  of  per- 
mitting  or  arresting  at  pleasure  the 
flow  of  a  liquid  through  a  pipe 

Cock-hoot y  a  smaU  boat  used  on  rivers 

Cock-pU,  that  part  of  a  ship  which  is 
appropriated  to  the  use  of  the  sur- 
geon, being  the  place  where  the 
wounded  are  dressed;  it  is  near 
thehatchvray,  and  under  the  lower 
gun-deck 

Codde,  the  skiorl  of  the  Swedes  and 
the  school  of  the  Germans  :  a 
laminated  mineral  substance  of  a 
blackish  brown  colour,  Mke  tin 

Cocoa  wood,  the  heart  of  which  is  sel- 
dom sound,  is  much  used  in  turnery 


105 


E  5 


coc 


COKE. 


COK 


Coetilist  according  to  Pliny,  a  brick 
hardened  by  burning 

Cod'lme,  an  eighteen-thread  line 

Co-efficientSf  in  algebra,  are  numbers 
or  letters  prefixed  to  other  letters 
or  unknown  quantities,  into  which 
they  are  supposed  to  be  multiplied ; 
and  therefore  with  such  letters,  or 
the  quantities  represented  by  them, 
making  a  product,  or  co-efficient 
product 

Ceelumf  according  to  Yitruvius,  a 
soffit  or  deUng 

Qenobiumf  anciently  a  monastery  of 
monks  or  friars 

C^feTf  in  Cornish  mining,  a  snudl 
wooden  trough  which  receives  the 
tin  cleansed  from  its  impurities  or 
slime 

Cofee-tree,  a  wood  of  a  light  greenish 
brown,  close-grained,  and  small  in 
stature,  sometimes  used  by  cabinet- 
makers 

Cqfer,  a  deep  panel  in  a  ceiling ;  also 
applied  to  a  casket  for  keeping 
jewels,  and  sometimes  to  a  chest 

Coffer-dam,  a  hollow  space  formed 
by  a  double  range  of  piles,  with 
clay  rammed  in  between,  for  the 
purpose  of  constructing  an  en- 
trance lock  to  a  canal,  dock,  or 
basin,  or  for  the  piers  of  a  bridge 

Coffin,  in  Cornish  mining,  old  work- 
ings which  were  all  worked  open 
to  g^ass,  without  any  shafts,  by 
digging  and  casting  up  the  tin 
stuff  from  one  stall  of  boards  to 
another 

Coffin,  a  wooden  case  in  which  a 
dead  body  is  placed,  sometimes  en- 
cased in  lead:  anciently,  stone 
coffins  were  used  for  interment 

Cog,  the  wooden  tooth  of  a  large 

,    wheel 

Cog-teeth  are  formed  of  a  differentma- 
terial  from  the  body  of  the  wheel : 
a  timber  tooth  on  a  cog-wheel  is 
one  made  of  wood,  when  the  teeth 
stand  perpendically  to  the  plane  of 
the  wheel 

Cog-wheel,  an  iron  wheel  with  wooden 
teeth  or  cogs 

Cohesion  qf  fluids,  M.  Monge  and 
others  assert  that  the  phenomena 

106 


of  capillary  tubes  are  referable  to 
the  cohesive  attraction  of  the  su< 
perficial  particles  only  of  the  fluids 
employed,  and  that  the  surface  must 
consequently  be  formed  into  curvet 
of  the  nature  of  linteariae,  which 
are  supposed  to  be  the  results  of  a 
uniform  tension  of  a  surface  resist- 
ing the  pressure  of  a  fluid,  either 
nniform  or  varying  according  to  a 
given  law 

Cohesion,  the  attraction  which  takes 
place  between  the  particles  of  bo- 
dies, denoting  that  force  by  which 
the  particles  firmly  cohere 

Cohesion  and  resistance  of  fluids,  as 
examined  by  the  force  of  torsion. 
Pressure  does  not  augment  the 
friction;  on  the  contrary,  the  re- 
sistance is  greater  when  the  im- 
mersion is  only  partial.  Greasing 
wood  does  not  lessen  the  friction : 
the  friction  of  oil  is  17^  times  as 
great  as  that  of  water.  A  part  of 
the  friction  is  proportional  to  the 
velocity:  the  constant  part  is  al- 
most insensible.  Thus  a  circle  *195 
metre  in  diameter,  turning  in  water 
with  a  velocity  equal  to '  1 4  m.  in  1  '^ 
meets  a  resistance  equivalent  to  a 
weight  of  1  gramme  acting  on  a 
lever  of  '143  m.  The  portion  pro- 
portional to  the  velocity  is  equiva- 
lent to  *042  gr.  for  a  surface  equal 
to  twice  such  a  circle  moving  in  its 
own  direction  with  a  velocity  of 
•01  m. 

Cohesive  strength  of  materials.  The 
force  of  cohesion  may  be  defined 
to  be  that  force  by  which  the  fibres 
or  particles  of  a  body  resist  separa- 
tion, and  is  proportioned  to  the 
number  of  fibres  in  the  body,  or  in 
the  area  of  its  section. 

Coiling,  a  serpentine  winding  of  ropes, 
by  which  they  occupy  a  small  space, 
and  are  not  liable  to  be  entangled 
amongst  one  another  in  working 
the  sails  of  a  ship 

Coin  or  quoin,  the  angle  of  a  building; 
used  also  for  the  machicolation  of  a 
wall 

Coke,  charred  pitcoal 

Coke.    The  most  valuable  of  the  se- 


COK 


COKE. 


COK 


condaiy  products  of  a  gas  estab- 
liflhment  is  coke.  The  best  kind 
is  obtained  from  coal  when  car- 
bonized  in  large  masses,  in  oTens 
constmcted  on  purpose.  In  a  gas 
manufactory,  the  production  of  coke 
being^  of  minor  inaportance  to  tbe 
formation  of  good,  gas,  it  is  gene- 
rally of  an  inferior  quality  to  that 
made  in  coke  ovens,  where  it  is  the 
primary,  and  indeed  sole  object  for 
which  the  coal  is  carbonized.  But 
gas-coke  is  excellent  for  many  pur- 
poses in  the  arts  and  raanofactm^, 
producing  «s  clear  a  fire  as  that  of 
the  first  quality,  though  it  is  neither 
so  lasting  nor  so  free  from  slag :  for 
domestic  use,  however,  it  is  unob- 
jectionahle,  and  may  be  burnt  both 
in  the  drawing-room  and  kitchen 
with  economy  and  comfort. 

The  distinguisliing  characters  of 
TOod  coke  are,  first,  a  clean,  granu- 
lu  fracture  in  any  direction,  with 
a  oearly  lustre,  inclming  to  that 
exhibited  by  cast  iron.  Secondly, 
density,  or  close  proxhnity  of  its 
particles,  which  «ihere  together  in 
masses,  and  specific  prayi^  of  1-10, 
or  rather  higher.  Thirdly,  when 
exposed  to  awhite  heat,  it  consumes 
entirely  away ,  without  leavmg  either 
olsur  or  ashes* 

It  is  invariably  the  case  that  the 

Quality  of  the  coke  is  inversely  as 

that  of  the  gas.  The  manufacturer 

must  not  expect  to  produce  both  of 

the  best  quality.     The  process  by 

which  the  hest  gas  is  made  gene- 

raUv  leaves  the  coke  Ught,  spongy, 

and  friable,  idthough  an  increase  of 

oTiantity  is  gained ;  for  the  simple 

reason,  that  the  degree  of  heat  and 

the*    circumstances  required  to 

form  perfect  coke  must  be  entirely 

chani^d  when  gas  of  a  high  specific 

gravity  is    *®  ^  obtained.    Thus 

Were  inasses  of  coal  exposed  to  a 

red  heat  in  close  vessels  are  acted 

upon  by  slo^  degrees,  the  external 

r^\Sons  preventing  heatfrom  pene- 

^tinz  into  the  interior  until  most 

of  the  bitumi"^^^  portions  are  given 

off  in    condensable  vapour,  or  as 


charcoal  and  free  hydrogen;  the 
after-prodocts  being  light  carbu- 
retted  hydrogen,  carbonic  oxide, 
and  carbonic  acid  gases.    The  re- 
sidue is  a  carbon  of  a  dense  granular 
composition 
Coke,  as  prepared  for  use  in  locomo- 
tive and  other  steam  engines,  may 
be  regarded  as  purified  coal,  or  coal 
from  which  the  extraneous  matters 
not  conducive  to  combustion  have 
been  expelled  by  the  application  of 
heat.  It  appears  from  experiments 
that  the  heating  power  of  every 
description  of  fuel,  whether  coal, 
coke,  wood,  lignite,  turf,  or  peat, 
is  proportional  to  the  quantity  of 
carbon  it  contains,  and  that  from 
83  to  86  per  cent,  of  this  element 
enters  into  the  composition  of  any 
given  weight  of  Newcastle,  Durham, 
or  Lancashire  coal,  the  other  in- 
gredients being  hydrogen,  azote, 
oxygen,  and  ashes.  The  exact  pro- 
cess which  takes  place  in  the  con- 
version of  coal  into  coke  is  not  yet 
thoroughly  understood,   although 
the  result  can  be  readily  estimated, 
and  is  found  to  depend,  to  a  con- 
siderable extent,  upon  the  manner 
in  which  the  process  is  performed. 
Thus,  by  coking  in  close  ovens, 
Welsh  coal  loses  about  30  per  cent. 
of  its  weight ;  but  if  the  coking  be 
effected  in  uncovered  heaps  of  coarse 
lumps,  as  it  often  is  in  the  Welsh 
coal  and  iron  districts  (where  abun- 
dance is  allowed,  as  the  excuse  for 
extravagance  and  waste),  the  loss 
of  weight  is  from  50  to  55  per  cent. 
While  the  weight  is  thus  diminished 
by  coking  in  close  ovens,  the  bulk 
is  increased  from.22  to  23  per  cent. 
The  rapid  andcompletccombustion 
of  the  carbon  which  takes  place  in 
the  burning  of  coke  has  the  effect 
of  preventing,.to  a  considerable  ex- 
tent,'the  emission  of  that  palpable 
smoke  which  arises  from  the  com- 
bustion of  coal,  and  for  this  pro- 
perty- coke- was  resorted  to  for  use 
in  locomotive  engines,  when  the 
non-emission  of  smoke  was  imposed 
as  one  of  the  conditions  upon  which 


107 


COL 


COLLEGIATE  CHURCHES. 


COL 


ndlway  oompaniei  were  empowered 
by  Act  of  Parliament.  The  prac- 
tical advantages  since  found  to  be 
derived  from  the  burning  of  eoke 
instead  of  coal  are,  its  greater  power 
in  evaporating  water  and  prodncing 
steam,  and  the  less  rapid  destruction 
of  the  boiler  which  ensues  from  its 
employment 

Ck^arnif  the  little  frieze  of  the  capital 
of  the  Tuscan  and  Doric  column, 
placed  between  the  astragal  and  the 
annulets 

Cold  chiself  a  piece  of  steel  flattened 
and  sharpened  at  one  end,  which  is 
properly  tempered,  so  that  it  may 
be  used  for  cutting  metal 

Cold'harbourf  an  inn ;  a  shelter  from 
the  cold ;  a  protection  on  the  way- 
side for  travellen  benighted  or  be- 
numbed 

Cold  short  troii,iron  in  an  impure  state 

Cold-water  well  and  reservoir*  To 
effect  the  condensation  of  steam, 
the  water  is  very  commonly  raised, 
by  means  of  the  cold-water  pump, 
from  a  reservoir  or  well.  TMs  ab- 
sorbs from  the  engine  some  portion 
of  its  power.  Indeed,  when  the 
wells  are  deep,  the  quantity  of 
power  thus  expended  is  so  great, 
that  the  condensing  system  can 
no  longer  be  judiciously  applied. 
This  may  be  known  by  the  follow- 
ing investigation : 

Rule. — Multiply  the  weight  of 
water,  in  ponnd8,by  the  feetthrough 
which  it  passes  in  a  minute,  and 
divide  the  product  by  33,000 ;  the 


quotient  will  exhibit^  friction  ex- 
eluded,  the  horses'  power  expended. 

Example, — ^To  condense  103** ; 
Weight  of  cold  water  lOiba. 

per  gallon,  at  62°  of  tem« 

perature, 
Engine,  nominal  power.  •  4  hones. 
Water,  per  horse  power .  •  4  gals. 
Lift  of  do.,  or  height 

raised,  230  feet  per  minnte. 


Hence 


4  X  40  X  230 


aft  I-^  h.  power. 


33,000 

Cold-water  pump,  the  pump  for  sup- 
plying the  water  for  condensation 

CoUarf  in  ships,  an  eye  in  the  end  or 
bight  of  a  shroud  or  stay,  to  go 
over  the  mast-head 

Collart  in  turnery,  a  ring  inserted  in 
the  puppet  for  holding  the  end  of 
the  mandril  next  the  chuck,  in  or- 
der to  make  the  spindle  run  freely 
and  exactly 

Collar t  a  plate  of  metal  screwed  down 
upon  the  stuffing-box  of  a  steam 
engine,  with  a  hole  to  allow  the 
piston-rod  to  pass  through 

Collar  of  a  shaft,  the  timber  and 
boarding  used  to  secure  the  upper- 
most part  of  a  shaft  in  loose  rub- 
ble from  falling  in 

CoUar^beamf  a  beam  framed  across 
and  between  two  principal  rafters 

Collegiate  Churches  of  Great  Britain 
(list  of).  The  Colleges  generally 
omitted  in  the  Books  amount  to 
130  in  number,  scattered  mostly 
over  England  alone,  and  are  con- 
sequently not  here  included. 


NAlfB. 

Abergwilly  •    • 
Arundel .    •    • 
Astley     .    .    •. 
Attilbury     •    • 
Axminster  •    . 
Barnard  Castle 
Battlefield   •    . 
Beverley  •    .    . 
Biggar    •    .    . 
Bishop  Auckland 
Bunbury  •    .    • 
B<dton,   within  thel 
Castle  of)    .    •    J 

108 


OHDXB. 

Secular  Canons 

Do. 

Do. 


Do. 
Do. 
Do. 


Do. 
Do. 

Do. 


DATS. 

1287 

1375 

Edw.  III. 

Hen.  lY. 

temp.  Athels. 

Rich.  III. 

1403 
928 

1545 

1239 

1389 

Sichard  11. 


COUKTT. 

Carmarthenshise 

Sussex 

Warwickshire 

Norfolk 

Devonshire 

Durham 

Shropshire 

Yorisshire 

Lanarkshire 

Durham 

Cheshire 

Torkshire 


COL 


Boseham 

Botham  « 

Bothwell 

BnulgTOve 

Brecknf>ck 

Bridjjnorth 

Bromyard 

Biirford  . 

Camworth 

Chcster-le-Strect 

Chuwleagh  * 
Clovelley 
Constantin  • 
Coretorphin - 
Cotherstokc. 

Craa  .     *  • 

Ciediton.  • 

Crichton .  - 

Dalkeith .  - 

Darlington  • 
Diileton  . 

Dirleton  •  • 

Dumbarton  • 

Dunbar    .      • 
Dunglass 

Eton  .     * 

Fothering&y 

Foulis 

Glasency 

Gnonshall     < 

Graystoke 

Guthry    • 
HamOton 

Hastings 
HcmmingrltwirgB 

Heytesbury 

Highana  Ferrers 

Holyhead      • 

Howden  -      • 

InetoliBgh«"«» 

Ingham   * 
Irtlingbnrgh 

Kilmaiirs 
Kilmund  - 
Kirkhengh    - 
Lanchester  - 

Ledbury  •     - 
Uancadane  - 

Llandewi  Bre^* 

Ludlow    - 
Maidstone 

Manton  . 
Maybole 


COLLEGIATE  CHURCHES. 


COL 


OBDEIU 


Secular  Canons 


Do. 
Do. 

Do. 


Do. 
Augustine 


Secidar  Canons 
Do. 

Do. 


Do. 
Do. 
Premonstrant 


Secular  Canons 


PATB. 

Henry  L 

1418 

1398 

Richard  II. 

Henry  VIII. 

Wm.  Rnfus 

temp.  H.  III. 

Edward 

1423 

1286 

temp.  Ed.  I. 

Richard  II. 

1429 
1336 
1517 
905 
1449 
James  y. 

Do. 

1444 

1450 

1392 

1450 

Henry  VL 

1411 

Jas.  II.  Scot. 

1270 

Henry  I. 

1359 

Jas.  I II.  Scot. 

1451 

Henry  I. 

1426 

1300 

Henry  V. 

1266 
Edward  III. 

1360 
Richard  II. 

1403 

1442 

1283 
1400 
1283 
1187 

1269 

Edward  III. 

1441 


COUMTT* 

Snsaez 

Haddingtonshire 

Lanazkdiire 

Kent 

Brecknockshire 

Shropshire 

Herefordshire 

Shropshire 

Lanarkshire 

Durham 

Devonshire 

Do. 

Cornwall 

Edinburghshire 

Northamptonshire 

Fifeshire 

Devonshire 

Ediaburgfashire 

Do. 

Durham 

Edinburghshire 

Haddingtonshire 

Dumbartonshire 

Haddingtonshire 

Do. 

Buckinghamshire 

Northamptonshire 

Forfar 

Cornwall 

Staffordshire 

Cumberland 

Forfar 

Lanarkshire 

Sussex 

Yorkshire 

Wiltshire 

Northamptonshire 

Anglesea 

Yorkshire 

Northamptonshire 

Norfolk 

Northampton^iire 

Ayrshire 

Argyleshire 

Fifeshire 

Durham 

Herefordshire 

Carmarthenshire 

Cardiganshire 

Shropshire 

Kent 

Rutlandshire 

Ayrshire 


109 


COL 

COLLEGIATE  CHURCHES.                                CO: 

NAMK. 

ORDER. 

DATE. 

COUNTY,  &C. 

Merewell     .    .    .    . 

Secular  Canons 

Hampshire 

Methvin 

1433 

Perthshire 

Mettingham     .    .    . 

Richard  XL 

Suffolk 

Middleham  .    .     .     . 

Do. 

1476 

Yorkshire 

Newark 

Do. 

1330 

Leicestershire 

Newport 

Do. 

Shropshire 

North  Cadbuiy      .    . 

Do. 

Henry  V. 

Somersetshire 

Northwell    .    .    .    . 

Do. 

temp.  H.  IV. 

Bedfordshire 

Norton 

Durham 

Norton  sub  Cross  .    . 

Edward  III. 

Norfolk 

Noseley  .    .    .    .    . 

temp.  Ed.  I. 

Leicestershire 

Ottery 

Wm.  Conq. 

Deyonahire 

Penkridge    .    .    .    . 

John 

Staffordshire 

Fleshy 

Do. 

Richard  II. 

Essex 

Ponsbury    .    .    .    . 

Shropshire 

Restrairig    .... 

1515 

Edinburghshire 

Roslin 

1446 

Do. 

Rotherham  .    .    .    . 

Do. 

1481 

Yorkshire 

Rushworth  .    .    .    . 

Do. 

1342 

Norfolk 

Ruthyn   •    .    .    .    . 

1310 

Denbighshire 

Sample   .    .    .    .    . 

1505 

Renfrewshire 

Seton 

1493 

Edinburghshire 

Shottesbrooke  .    .    . 

Do. 

1337 

Berkshire 

Sibthorp 

Do. 

Edward  IL 

Nottinghamshire 

South  Mailing  .    .    . 

Sussex 

.    Southwell    .... 

Do. 

630 

Nottinghamshire 

Stafford 

Staffordshire 

Staindrop    .... 

Do. 

temp.  Hen.  IV 

Durham 

Stansted  le  Thele  .    . 

Do. 

1315 

Hertfordshire 

Stoke   •  

Do. 

1115 

Suffolk 

Stratford  on  Avon 

Edward  III. 

Warwickshire              ! 

St.  Buriens  .... 

. 

Cornwall  . 

St.  David's  .... 

Do. 

1365 

Pembrokeshire 

St.  ElizAbeth    .     .    . 

Do. 

1300 

Winchester 

St.  Giles 

1466 

Edinburgh 

St.  Martin's  le  Grand 

Do. 

700 

London 

St.  Mary      .    .     .    . 

Do. 

1123 

Warwick 

St.  Mary     .    .    .    . 

Do. 

King  Steph. 

Stafford 

St.  Mary's   .... 

Edinburgh 

St  Mary  Magdalen    . 

1426 

LinUttjgo'^shire 

St.  Mary  Ottery    .    . 

Do. 

1000 

Deyonf^ire 

St.  Michael,  Crooked  1 
lane    .    •    •    .      ' 

Do. 

1380 

London 

St.  Salvator.    .    .    . 

1458 

Fileshire 

St.  Stephen's    .    .    . 

Benedictine 

1292 

Westminster 

Sudbury 

Secular  Canons 

1374 

Suffolk 

Tamworth   .... 

Staffordshire 

Tattershall  .... 

Do. 

Henry  VI. 

Lincolnshire 

Tayne     

1481 

Ross-shire 

Thornton  upon  Hnmber 

Augustine 

1139 

Lincolnshire 

Tomson 

Edward  III. 

Norfolk 

Tonge     

Secular  Canons 

1410 

Shropshire 

TotenhaU     .... 

Wm.  Qpnq. 

Staffordshire 

110 


COL 


COLOURS,  SYMBOLIC. 


CO) 


NAME. 

Towcester  .  .  • 
Trinity  .... 
Tullibairdine  .  . 
Toxford  .... 
Wallingford.  .  • 
Warwick  •  .  • 
Wcstbury  .  .  . 
Winbum  .  .  • 
Windsor,  (St.  George's 

Chapel)  .  .  . 
Wingfield  .  .  • 
Wingham  .  •  • 
Wenslow  •  •  • 
W^olverhampton     • 

Wye 

Wykeham  .  •  • 
Tester     .... 


OBDBR. 


Secular  Canons 
Do. 


Do. 


} 


Do. 


Do. 
Do. 
Do. 
Do. 
Do. 


DATE. 

Henry  VI. 

1463 

1446 

Edward  III. 

Edward  I. 

1123 

824 

1349 

Wm.  Rufus 

1286 
Richard  II. 
996 

1447 

1387 


COUNTY. 

Northamptonshire 

Edinburghshire 

Perthshire 

Nottinghamshire 

Berkshire 

Warwickshire 

Gloucestershire 

Dorsetshire 

Berkshire 

Suffolk 

Kent    V 

Yorkshire 

Staffordshire 

Kent 

Winchester 

Haddingtonshire 


CoUi8um,in  mechanics.  Whenever  two 
bodies  act  on  each  other  so  as  to 
change  the  direction  of  their  rela- 
tive motions,  by  means  of  any  forces 
which  preserve  their  activity  un- 
diminished at  equal  distances  on 
every  side,  the  relative  velocities 
with  which  the  bodies  approach  to 
or  recede  from  each  other  will  al- 
ways be  equal  at  equal  distances 

Cb^VMirmm,  anciently  a  well  or  open- 
ing formed  at  intervals  in  the  chan- 
nel  of  an  aqueduct  for  procuring  a 
free  current  of  air  along  its  course, 
and  to  facilitate  the  operation  of 
clearing  away  foul  deposits  left  by 
the  waters 

Cologne  earth  is  a  native  pigment, 
similar  to  the  Vandyke  brown  in 
its  uses  and  properties  as  a  colour 

Cohnnadefdtaxi^e  of  columns,  whether 
attached  or  insulated,  and  support- 
ing  an  entablature 

Co/os««ttm,  a  name  given  to  the  theatre 
of  Vespasian,  eiUier  from  its  mag- 
nitude or  from  its  colossal  statue 
of  Nero ;  also  the  name  of  a  fine 
building  in  the  Regent's  Park 

Colossus,  a  statue  of  gigantic  dimen- 
sions, or  very  much  beyond  the 
proportions  of  nature 

Colour.  The  term  colour  being  used 
synonymously  for  pigment  is  the 
cause  of  much  ambiguity^  particu- 

in 


larly  when  speaking  of  colours  as 
sensible  or  in  the  abstract ;  it  would 
be  well,  therefore,  if  the  term  pig- 
ment were  alone  used  to  denote 
the  material  colours  of  the  palette 

Colourinfff  in  painting,  the  art  of  dis< 
posing  the  tints,  so  as  to  produce 
either  an  imitation  of  the  natural 
colours  of  the  objects  represented, 
or  force  and  brightness  of  effect 

Colouring,  though  a  subject  greatly 
inferior  to  many  others  which  the 
painter  must  study,  is  yet  of  suffi- 
cient importance  to  employ  a  con- 
siderable  share  of  his  attention ;  and 
to  excel  in  it,  he  must  be  well  ac- 
quainted with  that  part  of  optics 
which  has  the  nature  of  light  and 
colours  for  its  object.  Light,  how- 
ever simple  and  uncompounded  it 
may  appear,  is  nevertheless  made 
up,  as  it  were,  of  several  distinct 
substances;  and  the  number  and 
quantity  of  component  parts  have 
been  happily  discovered  by  the 
modems 

Colours  (symbolic),  in  antiquity,  the 
middle  ages,  and  modern  times. 

The  history  of  symbolic  colours 
is  but  little  known.  Colours  had 
the  same  signification  amongst  all 
nations  of  the  remotest  antiquity : 
this  conformity  indicates  a  common 
origin,  which  extends  to  the  earliest 


COL 


COLOURS,  SYMBOLIC. 


cot 


state  of  hamanity,  and  develops  its 
highest  energies  in  the  religion  of 
.  Persia:  the  dualism  of  light  and 
darkness  presents,  in  effect,  the  two 
types  of  colours  which  become  the 
symbols  of  two  principles,  benevo- 
lence and  malevolence.  The  an- 
cients admitted  but  two  primitive 
colours,  white  and  black,  whence 
all  others  are  derived. 

The  language  of  colours,  inti- 
mately connected  with  religion, 
passed  into  India,  China,  Egypt, 
Greece,  and  Rome,  and  re-appeared 
in  the  middle  ages;  the  large  win^ 
dows  of  Gothic  cathedrals  found 
their  explanation  in  the  books  of  the 
Zends,  the  Vedas,  and  the  paintings 
of  the  Egyptian  temples. 

Among  the  Egyptians,  the  pro- 
phets did  not  allow  metal-founders 
or  statuaries  to  represent  the  gods, 
lest  they  should  deviate  from  the 
rules. 

At  Rome,  the  penalty  of  death 
was  incurred  by  selling  or  being 
clothed  in  a  purple  stuff.  At  this 
day,  in  China,  any  one  who  wears 
or  buys  clothes  with  the  prohibited 
design  of  the  dragon  or  phoenix, 
is  subjected  to  300  stripes  and  three 
years'  banishment. 

-Symbolism  explains  this  severity 
of  laws  and  customs:  to  each  colour, 
to  each  pattern,  appertained  a  re- 
ligious or  political  idea ;  to  change 
or  to  alter  it  was  a  crime  of  apo- 
stacy  or  of  rebellion. 

Archseologistshaveremarkedthat 
Indian  and  Egyptian  paintings,  and 
those  of  Greek  origin,  named  Etrus- 
can, are  composed  of  plain  tints 
of  a  brilliant  colour,  but  without 
dend-tints;  the  pattern  and  the 
colour  had  a  necessary  signification, 
— ^it  was  essentially  restrictive:  per- 
spective, chiaro-oscuro,  and  demi- 
tints,  would  have  led  to  confusion. 

Christianity,  in  recalling  these 
forgotten  significations,  restores  a 
new  lenergy  to  the  language  of 
colours:  the  doctrine  taught  by 
Christ  was  not  therefore  new,  since 
it  borrowed  the  symbols  of  ancient 


religions.  The  Son  oi  God,  in  lead, 
ing  back  mankind  to  the  truth, 
came  not  to  change,  but  to  fulfil 
the  law; — ^this  law  was  the  worship 
of  the  true  God. 

'  The  three  languages  of  colours, 
divine,  consecrated,  and  profane, 
classify,  in  Europe,  the  three  estates 
of  society, — ^the  clergy,  the  nobles, 
and  the  people. 

The  large  glass  windows  of 
Christian  churches,  like  the  paint- 
ings  of  Egypt,  have  a  double  sig- 
nification,— ^the  apparent  and  the 
hidden ;  the  one  is  for  the  uniniti- 
ated,  and  the  other  applies  itself  to 
the  mystic  creeds.  The  theocratic 
era  lasts  to.  the  renaissance ;  at  this 
epoch,  symbohc  expressions  are  ex- 
tinct; the  divine  language  of  colours 
is  forgotten, — ^painting  became  an 
art,  and  is  no  longer  a  science. 

The  aristocratic  era  commences ; 
and  symbolism,  banished  from  the 
church,  takes  refnge  at  the  court : 
disdained  by  painting,  it  is  found 
again  in  heraldry.  Modem  paint- 
ing still  preserves  its  symbolism  in 
church  pictures :  St.  John  wears  a 
green  robe,  Christ  and  the  Virgin 
are  likewise  draped  In  red  and  blue, 
and  God  in  white. 

Natural  philosophy  recognizes 
seven  colours,  which  form  the  solar 
ray,  decomposed  by  the  prism; 
namely,  violet,  indigo,  blue,  green, 
yellow,  orange,  and  red.  Painting 
admits  but  five  primitives, — ^the  first 
and  last  of  which  are  rejected  by 
natural  philosophy, — white,  yellow, 
red,  blue,  and  black.  From  the 
combination  of  these  five  colours 
every  hue  is  produced. 

According  to  symbolism,  two 
principles  produce  all  colours,  light 
and  darkness. 

Light  is  represented  by  white, 
and  darkness  by  black ;  but  light 
does  not  exist  but  by  fire,  the  sym- 
bol of  which  is  red:  setting  out 
from  this  basis,  symbolism  auimits 
two  primitive  colours,  redand white. 
Black  was  considered  as  the  ne- 
gation of  colours,  and  attributed  to 


112 


COL 


COMBUSTION. 


COM 


'  the  spirit  ckf  darkness ;  red  is  the 
symbol  of  divine  loTe ;  white,  the 
symbc^  of  divine  wisdom.  From 
these  two  attributes  of  God,  love 
and  wisdom,  the  creatioB  of  the 
imiverse  emanates. 
.  Secondary  colours  represent  dif- 
ferent combinations  of  the  two  prin- 
ciples; yellow  emanates  from  red 
and  white ;  it  is  the  symbol  of  reve- 
lation of  tlie  love  and  of  the  wis- 
dom of  God. 

Blue  emanates  Hkewise  from  red 
and  white ;  it  indicates  divine  wis- 
dom manifested  by  life,  by  the  sinrit 
or  the  breath  of  God  (air,  azare) ; 
it  is  the  symbol  of  the  spirit  of 
truth. 

Green  is  formed  by  the  union  of 
yellow  and  blue;  it  indicates  the 
manifestation  of  love  and  wisdom 
in  action ;  it  was  the  symbol  of 
diarity,  and  of  the  regeneration  of 
the  soul  by  works. 

Gold  and  yellow  were,  in  Chris- 
tian symbolism,  the  emblems  of 
futh:  St.  Peter  was  represented  by 
the  illuminators  and  miniaturists  of 
the  middle  ages  with  a  golden* 
yellow  robe,  and  the  rod  or  the 
key  in  his  hand. 

Christianity  restored  truth  to 
mankind,  and  re-instated  symbolic 
language  in  its  original  purity*  In 
the  transfiguration,  the  countenance 
of  our  Lord  became  resplendent  as 
the  snn,  and  his  vesture  shone  like 
the  light.  Such,  in  their  highest 
energy,  are  the  symbols  of  chvine 
love  and  wisdom.  The  angel  who 
rolled  away  the  stone  from  the  se- 
pulchre reproduced  them  in  an  in-< 
ferior  order, — his  face  shone  like 
lightnings  and  his  robe  was  white 
as  snow.  Finally,  in  the  last  de- 
greCf  appeared  the  just,  in  robes 
washed  white  in  the  blood  of  the 
Lamb.  The  artists  of  the  middle 
ages  preserved  their  precious  tra- 
ditions, and  g^ve  to  Jesus  Christ, 
after  the  resmrection,  white  or  red 
costume. 
Coktmbariaf  the  holes  left  in  walls 
for  the  insertion  of  pieces  of  tim- 

113 


her ;  so  called  from  resembling 
the  niches  of  a  pigeon-house.  The 
niches  of  a  mausoleum,  made  iq 
receive  the  dneral  urns,  were  Ifte- 
wise  termed  cohsmbaria 

Cohmbanum,  a  place  of  sepultore 
used  for  the  ashes  of  the  Romans, 
after  the  custom  of  burning  the 
dead  had  been  introduced  among 
them 

Columen,  the  term  applied  to  tiie 
upright  timbers  of  a  roof,  eor- 
responding  to  the  modem  king- 
posts 

Cohimnf  in  architecture,  a  member  of 
a  cylindrical  form,  consisting  of  a 
base,  a  shaft  or  body,  and  a  ci^i- 
tal.  It  differs  from  the  pilaster, 
which  is  square  on  the  plan. 
Columns  should  always  stand  per- 
pendicularly 

Gohtntna  (Latin),  a  pillar  or  eolumn, 
used  in  architectore  (as  described 
in  the  orders),  placed  upright  for 
support  of  buildings,  jnindpally 
wrought  in  stone,  and  made  de- 
corative in  conformity  to  the  ordar 
and  style  of  architectural  compo- 
sition 

Cohtmngf  in  architecturo,  according 
to  Vitruvius,  of  the  three  orders. 
The  proportions  of  Corinthian  co- 
lumns aro  in  every  respect,  except- 
ing their  capitals,  similar  to  those 
of  Ionic;  although  their  form  is 
moro  gracefol  and  proportionably 
more  delicate,  by  reason  of  the 
greater  height  of  the  capitals ;  for 
Ionic  capitals  are  a  third  part  only 
of  the  lower  diameter  of  the  co- 
lumns, whereas  the  Corinthian  ca- 
pital is  equal  in  height  to  an  entire 
diameter.  The  peculiar  character 
of  the  capitals,  which  admits  of 
their  being  higher  than  those  of 
Ionic  columns  by  two-thirds  of  a 
diameter,  gives  beauty  to  them, 
by  permitting  an  increase  of  the 
height  without  violating  the  laws 
of  symmetry 
Combmtionj  the  operation  of  fire  upon 
an  inflammable  substance,  by  which 
it  smokes,  flames,  and  is  reduced 
to  ashes 


COM 


COMPARTMENT. 


COHi 


Comiu8tUmt  Spontaneoui,  Few  or  no 
chemical  combinations  can  ti^e 
place  without  a  disturbance  in  the 
equilibrium  of  caloric  in  the  sub- 
stances to  be  so  combined;  and 
when  caloric  is  thereby  eyolved  in 
sufficient  extent  and  rapidity,  and 
.  when  one  or  all  the  bodies  engaged 
may  be  freely  combustible,  ignition 
takes  place.  When  this  is  unin- 
tentional, or  is  the  result  of  igno- 
rance or  carelessness,  it  is  con- 
venient to  call  it  spontaneous  com- 
bustum. 

Thus  we  frequently  hear  of 
hayricks,  &c.,  on  fire;  occasion- 
ally, of  carts  loaded  with  quick- 
lime  being  burned  by  the  rain  fall- 
ing upon  the  lime.  There  are  also 
somewhat  apochryphal  accounts  of 
coal  in  coal-yards  being  destroyed 
in  like  manner.  But  the  most  im- 
portant instance  of  this  dass,  as 
far  as  regards  the  preservation  of 
Government  establishments,  is  the 
combustion  that  infallibly  and  ra- 
pidly ensues  when  greasy  hemp, 
flax,  or  cotton,  is  allowed  to  re- 
main loosely  heaped  together,  in 
any  quantity,  in  a  confined  unven- 
tilated  space. 

Full  proof  of  this  has  been  made 
by  experiment  in  the  dockyards ; 
and  there  is  much  reason  to  at- 
tribute many  fires  in  former  days 
to  carelessness  in  the  ropcrwalks 
and  hemp  stores  ;  in  consequence 
of  which,  rigorous  orders  have 
been  of  late  years  issued  as  to 
the  immediate  disposal  of  loose 
oakum  and  hemp  sweepings-*- all 
more  or  less  greased  or  oiled. 
The  very  oil-rags  used  by  engravers 
in  cleaning  plates,  when  heaped 
together  to  any  amount,  will  be 
consumed  in  a  few  hours. 

The  combination  in  question 
seems  to  be  between  the  oil  and  the 
oxygen  of  the  atmosphere.  Oil  has 
always  .  an  affinity  for  oxygen  ; 
though,  when  the  bulk  of  the  for- 
mer is  considerable  in  proportion  to 
the  surface,  the  action  is  but  feeble, 
and  the  results  not  ordinarily  ap- 

m 


predable :  but  in  the  case  of  ad 
mixture  of  such  fibrous  vegetabh 
bodies  as  hemp,  flax,  or  cottoi 
with  oily  matters,  where  the  ratic 
of  surface  to  solidity  is  great,  anc 
when  the  conditions  for  accumu- 
lating heat  are  favourable, — thit 
accumulation  soon  produces  igni- 
tion amongst  such  inflammable 
bodies  as  those  just  enumerated 

Come.  *Come  home  ;*  said  of  an  an- 
chor when  it  is  broken  from  the 
ground,  and  drags.  To  *  come  up ' 
a  rope  or  tadde,  is  to  slack  it  off 

Commandryt  a  religious  bouse  be- 
longing to  a  body  of  knights  of 
the  order  of  St.  Bernard  and  St. 
Anthony 

Commissuref  the  joint  between  two 
stones  in  masonry 

Common  pitch,  an  old  term  still  ap- 
plied by  country  workmen  to  a 
roof  in  which  the  length  of  the 
rafters  is  about  three-fourths  of  the 
entire  span 

Common  sewer  of  Rome:  it  was  near 
the  Senatorian  bridge,  and  was  16 
feet  in  diameter 

Communication  vaJves,  the  valves  in 
a  steam-pipe  which  connects  two 
boilers  to  an  engine,  for  cutting  off 
the  communication  between  either 
boiler  and  the  engine 

Communion  table,  a  piece  of  church 
furniture  usually  placed  near  the 
wall  of  the  east  end  of  the  chancel, 
and  enclosed  by  rails,  vrithin  which 
the  clergyman  stands  to  administer 
the  Sacrament 

Cwtqtanion,  a  wooden  covering  over 
the  staircase  to  a  ship's  cabin 

Compartition,  the  division  or  distri- 
bution of  the  ground-plan  of  an 
edifice  into  its  various  apartments 

Compartment  of  the  streets  within 
a  city.  According  to  Palladio,  re- 
gard must  be  always  had  to  the 
temperature  of  the  air,  and  also  to 
the  region  of  heaven,  or  the  cli- 
mate under  which  the  place  is 
situated;  because  where  the  air  is 
cold  or  temperate,  there  the  streets 
ought  to  be  made  large  and  noble, 
since  thereby  the  city  vrill  become 


COM 


COMPOSITE  ORDER. 


COM 


more  wholesome,  conyenient,  and 
beautiful:  it  being  certain  that 
by  how  much  less  piercing,  and 
withal  by  how  much  freer  the  air 
is,  by  so  much  the  less  will  it 
offend  the  head;  and  therefore 
by  how  much  more  a  town  is 
situated  in  a  cold  place,  or  in  a 
piercing  air,  and  that  the  houses  are 
high,  by  so  much  the  longer  ought 
the  streets  to  be  made,  that  they 
may  be  visited  by  the  sun  in  every 
part  of  them 

Con^artment,  a  division  or  separate 
part  of  a  general  design. 

Con^fOM  (Harris's  magneto-electric). 
The  inventor's  object,  in  the  appli- 
cation of  his  discovery  of  the  stea- 
dying  action  of  the  copper  ring, 
'*  is  the  combination  of  great  sensi- 
tiveness vritb  stability  and  simpli- 
city of  construction  ;  so  that  while 
the  needle  is  free  to  obey  the  mag- 
netic force  of  the  earth  in  the  most 
perfect  way,  it  yet  remains  tran- 
quil amidst  the  disturbing  motions 
to  which  a  ship  is  exposed ;  and 
this  stability  is  obtained  without 
the  aid  of  friction  or  other  me- 
chanical impediment,  which  often 
produce  an  apparent  steadiness,  or 
rather  sluggishness  of  the  compass 
(arising  from  indifference  to  mo- 
tion), at  the  expense  of  accuracy. 

"  Mlien  the  horizontal  position 
of  the  card  is  disturbed  by  any 
alteration  of  dip  incidental  to  a 
change  of  latitude,  it  is  to  be  cor- 
rected by  moving  the  silver  sliders 
on  the  needle. 

**  Should  the  compass  be  out  of 
use,  care  must  be  taken  to  let  the 
needle  hang  freely  in  the  meridian ; 
and  if  put  into  a  store-room,  or 
otherwise  set  by,  the  card  and 
needle  should  be  removed  alto- 
gether, and  placed  with  the  needle 
downward  in  the  shallow  box  pro- 
vided for  it, — the  north  point  being 
on  that  part  of  the  keeper  marked 
with  a  cross,  thus  x .  A  good 
compass  is  liable  to  deterioration 
and  damage  when  stowed  away 
without  regard  to   its    magnetic 


propeities,  and  without  due  care 
being  taken  to  preserve  the  agate 
and  the  point  of  suspension  in  a 
perfect  state." 

Compasses,  an  instrument  with  two 
long  legs,  working  on  a  centre  pin 
at  one  extremity;  used  for  draw- 
ing circles,  measuring  distances, 
setting  out  work,  &c. 

Compass-headed,  in  ancient  architec- 
tecture,  circular 

Compass-plane,  in  joinery,  a  tool  si- 
milar to  the  ■  smoothhig-plane  in 
size  and  shape,  but  the  sole  is 
convex,  and  the  convexity  is  in 
the  direction  of  the  length  of  the 
plane.  The  use  of  the  compass- 
plane  is  to  form  a  concave  cylin- 
drical surface,  when  the  wood  to 
be  wrought  upon  is  bent  with  the 
fibres  in  the  direction  of  the  curve, 
which  is  in  a  plane  surface  perpen- 
dicular to  the  axis  of  the  cylinder : 
consequently,  compass-planes  must 
be  of  various  sizes,  in  order  to 
accommodate  different  diameters. 

Compass-roof,  a  roof ., in  which  the 
braces  of  the  timbers  are  inclined 
so  as  to  form  a  sort  of  arch. 

Compass-saw,  in  joinery,  a*tool  for 
cutting  the  surfaces  of  wood  into 
curved  surfaces:  for  this  purpose 
it  is  narrow,  without  a  back,  thicker 
on  the  cutting  edge,  as  the  teeth 
have  no  set :  the  plate  is  about 
an  inch  broad,  next  to  the  handle, 
and  diminishes  to  about  one  quar- 
ter of  an  inch  at  the  other  extre- 
mity ;  there  are  about  five  teeth  in 
the  inch :  the  handle  is  single 

Compass-window,  a  bay  window,  or 
oriel 

Complement  (the)  of  an  arch  or  angle 
is  what  it  wants  of  90  degrees :  thus 
the  complement  of  50°  is  40°,  and 
the  complement  of  40°  is  50°. 

ComphAvium  (Latin),  the  interval  be- 
tween the  roofs  of  porticoes  which 
surround  the  cavsdium.  "The  rain 
was  admitted  through  this  opening, 
and  fell  upon  the  area  below, 
which  was  termed  by  some  authors 
the  imphtvium 

Con^osite  Order :  by  some  considered 


115 


COM 


CONCRETE. 


CO? 


not  a  distinct  order,  but  a  Tarietj 
of  the  Corinthian.  For  its  height 
and  proportion,  see  AreMteeturef 
Orders, 

Care  must  be  taken  in  Compo- 
site as  well  as  in  Corinthian  capi- 
tals, that  the  feet  of  the  lower 
leaves  do  not  project  beyond  the 
upper  part  of  the  column,  as  at 
St.  Carlo,  in  the  Corso  at  Rome, 
and  at  the  Banqueting-house  in 
London ;  for  nothing  can  be  uglier. 
Neither  are  these  leaves,  as  they 
mount,  to  bend  forwards,  as  in 
many  of  the  antiques,  and  in  some 
modem  buildings,  because  they 
then  hide  a  considerable  part  of 
the  upper  row  of  leaves,  and  give 
a  stunted  disagreeable  form  to  the 
whole  capital.  The  different  divi- 
sions of  the  acanthus  leaf,  and 
bunches  of  olive  or  parsley  which 
compose  the  total  of  each  leaf, 
must  be  firmly  marked,  and  massed 
in  a  very  distinct  manner :  the 
Items  that  spring  from  between 
the  upper  leaves  are  to  be  kept 
low  upon  the  vase  of  the  capital, 
while  rising  between  the  leaves, 
then  spring  gradually  forwards,  to 
form  the  different  volutes  ;  and 
the  ornaments,  which  sometimes 
are  used  to  adorn  the  sides  of  the 
angular  volutes,  are  never  to  pro- 
ject beyond  the  fillets  between 
which  they  are  confined. 

Composition  qfmotioih  in  mechanics, 
an  assemblage  of  several  directions 
of  motion  resulting  from  several 
powers  acting  in  (Cerent  though 
not  in  opposite  directions 

Composition,  in  painting,  is  a  tasteful 
and  proper  distribution  of  the  ob- 
jects of  a  picture,  in  grouping,  in 
the  attitudes,  and  in  the  draperies, 
and  the  mani^ment  of  the  back- 
ground 

Composition  and  symmetry  of  tem- 
ples. The  several  parts  wMch  con- 
stitute a  temple  ought  to  be  sub- 
ject to  the  Uws  of  symmetry,  the 
principles  of  which  should  be  fami- 
liar to  all  who  profess  the  scien^ 
of  architecture.    Symmetry  results 


from  proportion,  which,  in  tlii 
Greek  language,  is  termed  analogy 
Proportion  is  the  commensuratiot 
of  the  various  constituent  parti 
with  the  whole;  in  the  existence  o: 
which,  symmetry  is  found  to  con- 
sist; for  no  building  can  posses: 
the  attributes  of  composition  is 
which  symmetry  and  proportion 
are  disregarded,  nor  unless  there 
exists  that  perfect  conformation  oi 
parts  which  may  be  observed  in  a 
well-formed  human  being 

Con^fmand  arch,  according  to  Profes- 
sor Willis,  an  arch  which  lias  tlie 
archivolt  moulded  or  formed  into  a 
series  of  square  recesses  and  angles, 
on  the  principle  that  "  it  may  be 
resolved  into  a  number  of  concen- 
tric archways  successively  placed 
within  and  behind  each  other" 

Conqtound  pier,  a  term  applied  to  a 
clustered  column 

CompressUm^iht  result  of  pressing  or 
squeezing  matter  so  as  to  set  its 
parts  nearer  to  each  other,  and  to 
make  it  occupy  less  space 

Computation,  the  method  of  esti. 
mating  time,  weights,  measures, 
&c. 

Coneamerate,  to  arch  over 

ConcameratiOf  arched  woric 

Concave,  a  term  denoting  the  corvi- 
linear  vacuity  of  hollow  bodies         t 

Concentric,  having  a  common  centre; 
as  concentric  circles,  ellipses,  &c. 

Concha,  according  to  Dr.  Whewell,  a 
term  for  the  concave  ribless  sur- 
face of  a  vault 

Conclave,  a  private  or  secret  council; 
an  inner  room  for  meeting  pri- 
vately 

Concludinff  line,  a  small  line  leadings 
through  the  centre  of  the  steps  of 
a  rope  or  Jiieob*s  ladder 

Concrete,  a  composition  of  lime,  sand, 
pebbles,  or  other  materials,  now 
commonly  used  for  the  founda- 
tions of  buildings. 

The  general  employment  of  the 
mixture  of  lime  and  gravel,  com- 
monly known  by  the  name  of  con- 
crete, in  all  foundations  where, 
from  the  nature  of  the  soil,  pre- 


116 


CON 


CONCRETE. 


CON 


cautions  again&t  partial  settlements 
appear  necessary,    and   tUe  great 
pTobability  of  an  extension  of  its 
use  in  situatioiLS  inrhere  the  mate- 
rials of  which  it  is  composed  are 
eaaUy  and  cheaply  procured,  mnst 
of  course  render  it  a    subject  of 
great  interest  to  tbe  engineer. 

Much  valuable  information  on 
this  subject  wiU  be  found  in  a 
prize  essay  by  Mr.  G.  Godwin, 
pubUshed  in  the  '  Transactions  of 
the  Institute  of  British  Architects.' 
In  this  essay,  many  instances  are 
brought  forward  of  the  employment 
by  the  ancients  of  a  mixture  ana- 
logous to  concrete,  both  for  founda- 
tions and  for  walls.  Several  cases 
are  also  mentioned  in  which,  of 
late  years,  it  has  been  nsed  advan- 
tageously for  foundations,  by  some 
of  the  most  distinguished  architects 
and  civil  engineers.  In  these  lat- 
ter instances,  the  proportion  of  the 
ingredients  varies  from  one  of  lime 
and  two  of  gravel,  to  one  of  Ume 
and  twelve  of  gravel, — the  lime 
being  in  most  cases  Dorking  lime, 
and  the  gravel,  Thames  ballast. 
The  proportion,  however,  most 
commonly  used  now,  in  and  about 
London,  is  one  of  lime  to  seven  of 
b^last ;  though,  from  experiments 
made  at  the  b\iilding  of  the  West- 
minster New  Bridewell,  it  would 
appear  that  one  of  Ume  to  eight  of 
ballast  made  the  most  perfect  con- 
cretion. 

Concrete,  compounded  solely  of 
lime  and  screened  stones,  will 
never  assume  a  consistence  at  all 
equal  to  that  dT  which  sand  forms 
a  part.  The  north  wing  of  Buck- 
ingham Palace  affords  an  instance 
of  this:  it  was  first  erected  on  a 
mass  of  concrete  composed  of  lime 
and  stones,  and  when  subsequent 
alterations  made  it  necessary  to 
take  down  the  building  and  remove 
the  foundation,  this  was  found  not 
to  have  concreted  into  a  mass. 

Mr.  Godwin  states,  as  the  result 
of  several  experiments,  that  two 
parts  (^  stones  and  one  of  sand, 

117 


with  sufficient  Ume  (dependent  on 
the  quaUty  of  the  material)  to 
make  good  mortar  with  the  latter, 
formed  the  best  concrete.  As  the 
quaUty  of  the  concrete  depends, 
therefore,  on  the  goodneu  of  the 
mortar  composed  of  the  lime  and 
sand,  and  as  this  mnst  vary  with 
the  quaUty  of  the  Ume,  no  fixed 
proportions  can  of  course  be  laid 
down  which  wiU  suit  every  case.' 
The  proportions  must  be  deter- 
mined by  experiment;  but  in  no 
case  should  the  quantity  of  sand 
be  less  than  double  that  of  the  Ume. 
The  best  mode  of  compounding 
the  concrete  is  to  thoroughly  mix 
the  Ume,  previously  ground,  with 
the  ballast  in  a  dry  state ;  sufficient 
water  being  then  thrown  over  it  to 
effect  a  perfect  mixture,  it  should 
be  turned  over  at  least  twice  with 

•  shovels,  and  then  wheeled  away 
instantly  for  use.  In  some  cases, 
where  a  great  quantity  of  concrete 
has  to  be  used,  it  has  been  found 
advisable  to  employ  a  pug-miU  to 
mix  the  ingredients :  in  every  case 
it  should  be  used  hot. 

With  regard  to  the  quantity  of 
water  that  should  be  employed  in 
forming  concrete,  there  is  some 
difference  of  opinion;  but  as  it  is 
usually  desirable  that  the  mass 
should  set  as  rapidly  as  possible,  it 
is  not  advisable  to  use  more  water 
than  is  necessary  to  bring  about  a 
perfect  mixture  of  the  ingredients. 
A  great  change  of  bulk  takes  place 
in  the  ingredients  of  concrete  when 
mixed  together:  a  cubic  yard  of 
baUast,  vnth  the  due  proportion  of 
Ume  and  water,  mVL  not  make  a 
cubic  yard  of  concrete.  Mr.  God- 
win, from  several  experiments  made 
with  Thames  ballast,  concludes  that 
the  diminution  is  about  one-fifth. 
To  form  a  cubic  yard,  therefore,  of 
concrete,  the  proportion  of  Ume 
being  i^th  of  the  quantity  of  ballast, 
it  requires  about  30  cubic  feet  of . 
ballast,  and  3f  cubic  feet  of  ground 

>    Ume,  with  sufficient  water  to  effect 

-.   the  admixture. 


CON 


CONDUCTION,  ELECTRICAL. 


CON 


An  expansion  takes  place  in  the 
concrete  during  the  slaking  of  the 
lime,  of  which  an  important  use 
has  been  made  in  the  underpinning 
of  walls :  the  amount  of  this  ex- 
pansion has  been  found  to  be  about 
f ths  of  an  inch  to  every  foot  in 
height ;  and  the  size  thus  gained, 
the  concrete  never  loses. 

The  examples  from  which  the 
above  rules  are  deduced  are  princi- 
pally of  buildings  erected  in  or 
about  London;  the  lime  used  is 
chiefly  from  Dorking,  and  the  bal- 
last from  the  Thames.  It  is  very 
desirable  that  a  more  extended 
collection  of  facts  should  be  made, 
that  the  proportions  of  the  mate- 
rials, when  other  limes  and  gravel» 
are  used,  should  be  stated,  in  order 
that  some  certain  rules  may  be  laid 
down  by  which  the  employment  of 
concrete  may  be  regulated  under 
the  various  circumstances  which 
continually  present  themselves  in 
practice. 

The  Dorking  and  Hailing  limes 
are  slightly  hydraulic.  Will  com- 
mon Umes,  such  as  chalk,  and 
common  stone-lime,  answer  for 
forming  foundatiqps  of  concrete, 
where  the  soil,  although  damp,  is 
not  exposed  to  running  water  ?  Is 
it  possible,  even  with  hydraulic 
lime,  to  form  a  mass  of  concrete  in 
running  water  ?  If  common  lime 
will  not  answer,  may  it  not  be 
made  efficient  by  a  slight  mixture 
of  cement  ?  These,  and  questions 
similar  to  these,  are  of  great  in- 
terest;  and  facts  which  elucidate 
them  will  be  valuable  contributions 
to  the  stock  of  knowledge  on  this 
subject. 

It  is  a  question  for  consideration, 
whether  a  great  variety  of  sizes  in 
the  materials  used  would  not  form 
the  most  solid  as  well  as  the  hardest 
wall.  The  walls  of  the  fortress  of 
Ciudad  Rodrigo,  in  Spain,  are  of 
concrete.  The  marks  of  the  boards 
which  retained  the  semi-fluid  mat- 
ter in  their  construction  are  every 
where  perfectly  visible ;  and  besides 

118 


sand  and  gravel,  there  are  everjp 
where  large  quantities  of  round 
boulder-stones  in  the  walls,  from 
4  to  6  inches  in  diameter,  procured 
from  the  ground  around  the  city, 
which  is  every  where  covered  with 
them. 

Condensation,  the  conversion  of  Ya^ 
pour  into  water  by  cold 

Condenser,  in  steam  engines,  the  ves- 
sel connected  vrith  the  exhaust-port 
of  the  cylinder  of  a  low-pressure 
engine,  and  also  with  the  air-piunp, 
by  a  passage  at  the  bottom  fitted 
by  the  foot-valve  of  the  pump  :  it 
receives  the  steam  from  the  cylin- 
der, and  condenses  it  by  a  jet  of 
cold  water,  thus  forming  a  vacuum 
for  the  return  stroke :  the  water, 
air,  &c.  is  then  drawn  off  by  the 
air-pump,  and  discharged  into  the 
hot  well 

Conditorium,  a  secret  place;  a  sepul- 
chre ;  a  vault 

Conduction,  electrical,  a  series  of 
phenomena  in  electricity,  giving 
origin  to  a  classification  of  sub- 
stances  as  conductors  of  electricity. 
The  substances  which  properly 
come  under  this  conducting  or  non- 
electric class  are  principally  as  fol- 
lows: 

LIST  OF  ELECTRICAL  CONDUCTORS. 

Every  metallic  substance  known. 

Well-burned  charcoal. 

Plumbago. 

Concentrated  and  diluted  adds,  and 

saline  fluids. 
Water,  and  moist  vegetable  matter. 
Living  animal  matter. 
Flame — smoke — steam. 

The  distinctive  difference  in  the 
conducting  and  non  -conducting 
property  of  bodies  may  be  readily 
illustrated  in  the  following  way : 

Excite  a  glass  tube  and  wire, 
and  bring  the  ball  of  the  wire  into 
contact  with  any  of  the  electrics, 
as  a  rod  of  glass,  a  stick  of  sealing- 
wax,  or  brimstone  rendered  per- 
fectly dry :  the  attractive  power  of 
the  ball  and  wire,  together  with 
the  tube,  will  not  be  in  any  sensi- 
ble degree  impaired.  Let  the  elec-  | 


CON 


CONDUCTION,  ELECTRICAL. 


CON 


trifled  ball  now  touch  the  walk  of 
the  room  or  other  conducting  sub- 
stance communicating  with  the 
ground;  the  attractive  power  will 
instantly  yanish. 

It  is  evident  from  these  facts 
that  all  electric  substances  are  non- 
conductors or  ingulatarSt  as  they 
are  appropriately  termed;  whilst, 
on  the  other  hand,  non-electric 
substances  are  transmitters  or  con- 
ductors of  electrical  action. 

When,  therefore,  any  condnct- 
ing  substance  is  placed  on  an  elec- 
trical support,  such  as  a  rod  of 
glass  or  shell-lac,  it  is  considered 
to  be  insulated,  and  is  termed  an 
intulated  conductor;  when  elec- 
trified by  contact  with  any  excited 
or  other  electrified  body,  it  is  said 
to  be  charged.  The  electrical 
charge  thus  communicated  to  an 
insulated  conductor  appears  to  be 
collected  about  its  surface,  and  to 
be  rather  dependent  on  that  than 
on  the  solid  content.  Thus,  if  two 
metallic  spheres  or  cylinders,  the 
one  solid,  the  other  hollow  and 
extremely  light,  be  suspended  by 
silk  lines,  or  placed  on  dry  insu- 
lating supports,  and  be  charged  by 
contacts  with  an  excited  tube,  the 
attractive  energy  of  each  upon  any 
light  substance  presented  to  it  will 
be  found  quite  alike  in  each.  In 
this  experiment  the  insulators  must 
be  very  dry  and  perfect. 

The  best  insulating  substances 
are  of  the  vitreous  and  resinous 
class,  such  as  shell-lac,  brimstone, 
dry  glass  rods,  vitrified  and  crys- 
talline bodies:  to  these  may  be 
added  silk. 

The  best  conducting  substances 
are  principally  metallic  bodies,  sa- 
line fluids,  and  common  charcoal. 
It  should,  however,  be  here  un- 
derstood, that  modem  researches, 
especially  those  of  Faraday,  lead  us 
to  conclude  that  there  are  really 
eno  substances  which  perfectly  con- 
duct or  perfectly  obstruct  electrical 
action.  The  insulating  and  con- 
ducting power  is,  in  fact,  a  differ- 


ence of  degree  only :  still,  the  ex- 
treme differences  are  so  great,  that 
if  classed  in  relation  to  such  dif- 
ferences, those  at  the  extremes  of 
the  series  admit  of  being  considered 
the  one  as  insulators,  the  other  as 
conductors;  whilst  the  interme- 
diate terms  are  made  np  of  sub- 
stances which  may  be  considered 
as  imperfect,  taken  as  either.  Con- 
versely, every  substance  is  capable 
of  excitation  by  friction ;  yet  the 
differences  in  this  respect  are  so 
great  as  to  admit  of  some  bodies 
being  called  electrics  and  others 
non-electrics,  with  an  intermediate 
class  between  these  extremes, 
which  may  be  termed  imperfect 
electrics. 

Series  of  conductors  and  mra- 
lators, — ^Metals  and  concentrated 
acids  are  found  at  the  conducting 
extremity  of  such  a  series, — ^shell- 
lac,  brimstone,  all  vitreous  and 
resinous  bodies,  at  the  other  or 
electric  extremity ;  whilst  the  im- 
perfect or  intermediate  substances 
comprise  such  matter  as  common 
earth  and  stones,  dry  chalk,  mar- 
ble, porcelain,  paper,  and  alkaline 
matter. 

The  attractive  power  evinced  by 
any  electrical  body  in  a  state  of 
excitation,  although  the  first  and 
usually  the  most  evident  electrical 
effect,  is  yet  not  the  only  force 
which  seems  to  result  from  this 
curious  condition  of  common  mat- 
ter. On  a  closer  examination  of 
the  phenomena,  a  new  class  of 
facts  present  themselves,  of  re- 
markable interest.  If  the  excita- 
tion be  considerable,  and  the  at- 
tracted body  insulated,  it  will,  after 
being  drawn  into  contact  with  the 
electrified  substance,  rebound  from 
it  with  great  violence,  as  if  repelled 
by  some  new  power,  and  will  not 
be  again  attracted  until  it  has  had 
conducting  communication  with 
the  earth,  or  some  other  mass  of 
matter  capable  of  reducing  it  to  its 
original  condition  before  the  con- 
tact. 


119 


CON 


CONSERVATORY. 


CON 


Qmduit,  a  structure  forming  a  reser- 
voir for  water,  and  from  which  it 
is  drawn  for  use 

Cone,  a  solid  body  having  a  circular 
base,  and  its  other  extremity  ter- 
minating in  a  single  point  or  vertex. 
Cones  are  either  right  or  oblique 

Cone-plate f  a  strong  plate  of  cast  iron 
fixed  vertically  to  the  bed  of  a  lathe, 
with  a  conical  hole  in  it,  to  form  a 
support  for  the  end  of  a  shaft 
which  it  is  required  to  bore 

Confessional,  a  recess  or  seat  in  which 
the  priest  sits  to  hear  the  confes- 
sions of  penitents 

Conge,  another  name  for  the  echinus 
or  quarter-round,  as  also  for  the 
cavetto :  the  former  is  called  the 
swelling  conge,  the  latter  the  hol- 
low conge 

Cotitc  sections,  the  curves  formed  by 
the  intersection  of  a  circular  cone 
and  a  plane;  the  former  being 
either  oblique  or  right 

Conical  points,  in  turnery,  the  cones 
fixed  in  the  pillars  for  supporting 
the  body  to  be  turned:  that  on  the 
right  hand  is  called  the  fore  centre, 
and  that  on  the  left  hand,  the  back 
centre 

Conissinet,  the  stone  which  crowns  a 
pier,  or  that  lies  immediately  over 
the  capital  of  the  impost,  and  under 
the  sweep.  The  bed  of  it  is  level 
below,  and  curved  above,  receiving 
the  first  rise  or  spring  of  the  arch 
or  vault 

Conis^erium,  an  apartment  in  the  pa- 
laestra, in  which  sand  was  kept  for 
springing  the  athletie,  after  they 
had  been  anointed 

Connecting-rods,  in  locomotive  en- 
gines, the  strong  iron  rods  which 
connect  the  piston  to  the  driving- 
wheel  axle,  and  thus  give  motion 
to  all  the  machinery 

Connecting-rods,  in  locomotive  en- 
gines,  outside  or  side  rods,  those 
which  connect  together  the  wheels 
of  goods  engines.  They  are  seen 
outside  the  wheels,  making  an  ir- 
regular forward  motion,  like  water- 
men rowing  a  boat.  By  connect- 
ing the  wheels  together,  one  pair 

120  ^ 


cannot  slip  without  the  others, 
and  the  greatest  practicable  adhe- 
sion is  thus  obtained 

Connecting-rod  strcqts,  in  locomotive 
engines,  strong  pieces  of  iron  bent 
like  the  letter  d,  which  fit  the 
ends  of  the  connecting-rod,  and 
into  which  the  axle-beaiing  is  fitted 
in  two  parts.  They  are  attached 
to  their  respective  ends  of  the  rod 
by  keys  and  cotters,  which  are 
taken  out,  and  the  half  of  the 
bearing  also,  when  a  connecting- 
rod  has  to  be  put  on.  The  strap 
and  half-bearing  are  then  brought 
over  the  axle  or  cross-head,  the 
other  half-bearing  put  into  the 
strap,  the  end  of  the  rod  brought 
up  against  the  bearing,  and  secured 
by  the  keys  and  cotters.  Taking 
off  a  rod  is  of  course  the  reverse  of 
putting  one  on 

Connecting-rod  bearings,  in  locomo- 
tive engines,  the  giin-metal  or 
composition-metal  bearings  fitted 
into  the  straps,  to  suit  the  parti- 
cular part  they  are  to  work  on 

Conning,  directing  the  helmsman  in 
steering  a  vessel 

Conservation,  the  ceremony  of  sancti- 
fying or  making  holy 

Conservatory,  a  superior  kind  of 
greenhouse,  for  preserving  curious 
and  rare  exotic  plants.  It  is  made 
with  beds  of  the  finest  composts, 
into  which  the  trees  and  plants  are 
removed  for  culture  and  preserva- 
tion. Its  construction  is  more  ca- 
pacious than  the  ordinary  green- 
house, and  it  is  furnished  in  a  supe- 
rior style,  provided  with  a  free  ad- 
mission of  light,  and,  in  addition, 
with  flues  or  boiUng-water  pipes 
to  raise  the  temperature  when  ne- 
cessary, and  also  contrivances  for 
the  introduction  of  fresh  air 

Consideration  (the),  which  one  ought 
'  to  have  before  he  begins  to  build. 
Palladiosays,  "  The  first  thing  that 
requires  our  consideration,  when 
we  are  about  to  build,  is  the  plan, 
and  the  upright  of  the  edifice  we 
propose  to  erect."  Three  things, 
according  to  Vitruvius,  are  chiefly 


CON 


CONTOURING. 


CON 


to  be  considered,  without  vrhich  a 
building  cannot  be  of  any  yalae. 
Tbese  are,  conveniency,    solidity, 
and  beauty :  for  no  edifice  can  be 
allowed  to  be  perfect,  if  it  be  com- 
modioas  and  not  durable;  or,  if 
bemg  durable,    it   be    subject  to 
many  inconveniences ;  or  if  having 
both  solidity  and  conveniency,  it 
hu  no  beauty  or  uniformity. 
Omittory  court,    a  spiritual  court, 
fonnerly  held  in  the  nave  of  the 
cathedral  church 
Cmokf  a  bracket  or  truss,  mostly 
vith  scrolls  or  volutes  at  the  two 
ends,  of  unequal    size    and  con- 
trasted, but  connected  by  a  flowing 
Une  from  the  back  of  the  upper 
one  to  the  inner  convolving  face  of 
the  lower 
Omtant  white,  permanent  white,  or 
;    barytic  white,  is  a  sulphate  of  ba- 
lytes,  and,  when  well  prepared  and 
'    free  from  acid,  is  one  of  the  best 
I    wbites  for  water-painting,  being  of 
superior  body  in  water,  but  desti- 
tute of  this  quality  in  oil 
^^rsG^ton,  in  architecture :  for  this 
the  chief  requisites  are,  magnitude 
and  strength,  and  the  art  of  distri- 
buting the    different    forces  and 
atrains  of  the  parts  and  materials 
of  a  building  in   so  scientific  a 
manner  as  to  avoid  failure  and  to 
insure  durability 
Continuous  imposts,  according  to  Pro- 
fessor Willis,  are  the  mouldings  of 
an  arch  which  are  continued  with- 
out interruption  down  the  uprights 
to  the  ground  or  base,  the  impost 
point  having  no  mark  or  distinc- 
tion of  any  kind 
Contouring  (surveying  altitudes  and 
levels).    This  term  is  applied  to 
the  outline  of  any  figure,  and  con- 
sequently to  that  of  any  section  of 
asolidbody;  but  when  used  pro- 
fe8sionally>  in  connection  with  the 
forms  of  ground,  or  of  works  of 
defence,  the  outline  of  a  horizontal 
section  of -the  ground,  or  works,  is 
alone  to  be  understood  by  it. 
When  the  forms  of  ground,  or 

works,  are  described  by  contours, 

■■ — 

121 


or  horizontal  sections,  these  sec- 
tions are  taken  at  some  fixed  ver- 
tical interval  from  each  other, 
stuted  to  the  scale  of  the  drawing, 
or  to  the  subject  in  hand ;  and  the 
distance  of  each,  above  or  below 
some  assumed  plane  of  compari- 
son, is  given  in  figures  at  the  most 
convenient  places  on  the  plan. 
When  the  scale  of  the  drawdng  is 
about  100  feet  to  an  inch,  2  or  3 
feet  will  be  found  a  convenient 
vertical  interval  between  the  con- 
tours ;  and  however  large  the  scale 
of  the  plan,  it  will  scarcely  be 
found  necessary  to  obtain  contours 
with  a  less  vertical  interval  than  2 
feet.  If  the  scale  of  the  plan  be 
about  250  feet  to  an  inch,  or  the 
ordinary  special  survey  scale  of  4 
chains  to  an  inch,  5  feet  will  prove 
a  convenient  vertical  interval ;  and 
with  a  horizontal  scale  of  from  500 
to  800  feet  per  inch,  10  feet  may 
be  taken  as  the  vertical  intervaL 

In  tracing  and  surveying  the 
contours  of  ground,  the  following 
process  may  be  adopted:  com- 
plete the  survey  of  the  occupation 
of  the  ground,  the  streams,  &c., 
and  determine  carefully  the  alti- 
tudes of  the  trigonometrical  points 
employed  above  the  intended  place 
of  comparison:  t-ake  an  accurate 
trace  frx>m  the  plot  of  one  of  the 
triangles,  which,  if  the  distances 
between  the  trigonometrical  points 
are  properly  proportioned  to  the 
scale  of  the  plan,  will  generally  be 
a  convenient  piece  in  point  of  size 
to  contour :  take  this  trace  to  the 
ground,  and  find  upon  the  ground, 
and  mark  upon  the  trace,  the  points 
where  each  of  the  intended  con- 
tours will  cut  the  boundary  lines  of 
the  triangle. 

Contraction^  the  effect  of  cold  upon 
a  warm  body,  causing  a  diminution 
in  its  size  by  the  particles  ap- 
proaching each  other 

Coniramuret  an  out-wall  built  about 
the  wall  of  a  city  or  fortification 

Convent,  a  building  appropriated  to 
religious  persons ;  a  nunnery 


CON 


CORINTHIAN  ORDER. 


COR 


Convocation  and  ConvocatorSt  or  par- 
liament of  tinners.  All  Stannary 
laws  are  enacted  by  the  several 
convocations,  and  carry  with  them 
all  the  force  and  law  of  acts  of 
parliament. 

Coopertoriumf  the  roof  of  a  building 

Co-ordinateSf  in  the  theory  of  curves, 
any  absciss  and  its  corresponding 
ordinate 

Coping,  the  reversing  course  of  a 
wall,  either  flat  or  sloping  on  the 
upper  surface,  to  throw  off  water 

Coppe-houae,  anciently  a  tool-house 

Copper^  one  of  the  six  primitive 
metals,  and  the  most  ductile  and 
malleable  after  gold  and  silver. 
Of  this  metal  and  lapis  calaminaris 
is  made  brass,  which  is  compara- 
tively a  modern  invention 

Copper  green  (colour) ;  the  appellation 
of  a  class  rather  than  of  an  indi- 
vidual pigment,  under  which  are 
comprehended  verdigris,  verditer, 
malachite,  mineral  green,  green 
bice,  Scheele's  green,  Schweinfurt 
or  Vienna  green,  Hungary  green, 
emerald  green,  true  Brunswick 
green,  lake  green,  mountain  green, 
African  green,  French  green,  Saxon 
green,  Persian  green,  patent  green, 
marine  green,  Olympian  green,  &c. 
The  general  characteristic  of  these 
greens  is  brightness  of  colour,  well 
suited  to  the  purposes  of  house- 
painting,  but  not  adapted  to  the 
modesty  of  nature  in  fine  art. 

Coral  wood  is  of  a  fine  red  colour, 
hard,  and  polishable 

Corbel,  or  CorbeiUe,  a  short  piece  of 
timber  or  stone  let  into  a  wall  half 
its  length  or  more,  as  the  burthen 
superimposed  may  require,  to  carry 
a  weight  above  it,  and  projecting 
from  the  general  face  of  the  work :  it 
is  carved  in  various  fanciful  ways ; 
the  commonest  form  is,  however, 
that  of  an  ogee 

Corbel,  in  Gothic  architecture,  a  pro- 
jecting stone  or  piece  of  timber 
which  supports  a  superincumbent 
weight 

Corbel-table,  a  row  of  corbels  sup. 
porting  a  parapet  or  cornice 

122 


Corbel-table,  a  cornice  supported  by 
corbels 

Corbie  8tep8,  steps  up  the  .sides  of  a 
gable,  found  in  old  houses  in 
FUnders,  Holland,  &c. 

Corbona,  in  mining,  a  dropper  from  a 
lode  in  irregular  masses 

Core,  with  the  Cornish  tinmen,  is  a 
division  of  time  and  labour 

Corinthian  Order.  The  three  columns 
in  the  Campo  Vaccino,  supposed 
remains  of  the  temple  of  Jupiter 
Stator,  are  generally  allowed  to  be 
the  most  perfect  models  of  the 
Corinthian  order  amongst  the  an- 
tiques at  Rome.  Palladio,  in  his 
fourth  book,  where  he  gives  the 
whole  profile  at  large,  acknow- 
ledges that  he  never  had  seen  any 
work  better  executed,  or  more  deli- 
cately finished ;  that  its  parts  are 
beautifully  formed,  well-propor- 
tioned, and  skilfully  combined ;  all 
which  last  qualities  are  certainly 
signified  by  his  Benissimo  intesi. 

With  these  favourable  senti- 
ments, it  is  extraordinary  that,  in 
his  design  of  the  Corinthian  order, 
he  should  have  so  very  considerably 
deviated  from  this  excellent  origi- 
nal as  scarcely  to  leave  the  smallest 
shadow  of  resemblance. 

Vignola,  in  his  Corinthian  pro- 
file, has  chiefly  imitated  the  above- 
mentioned  fragment,  and  the  inte- 
rior order  of  the  Pantheon,  another 
very  perfect  model.  His  compo- 
sition is  uncommonly  beautiful, 
and,  without  dispute,  superior  to 
that  of  any  other  master :  he  art- 
fully collected  all  the  perfections 
of  his  originals,  and  formed  a  whole 
far  preferable  to  either  of  them. 
(For  height  and  proportion,  see 
Architecture,  Orders,) 

Comerstonet,  in  architecture,  the  two 
stones  which  stand  one  in  each  jomt 
of  the  chimney  . 

Cornice,  the  projection,  consisting  of 
several  members,  which  crowns  or 
finishes  an  entablature,  or  the  body 
or  part  to  which  it  is  annexed.  The 
cornice  used  on  a  pedestal  is  caUed 
the  cap  of  the  pedestal 


I 


COR 


1 


I  ConutM  engine,  a  single-acting  beam 
engine,  used  for  raising  water:  the 
steam  is  worked  Tery  expansively, 
and  used  for  the  down-stroke  only, 
to  raise  an  immense  weight,  fas- 
tened to  the  pomp-rod,  at  the  end 
of  the  beam :    the   steam  having 
acted  for  the  down-stroke,  and  the 
entrance-valve  being  closed,  a  com- 
monication  is  formed  between  the 
top  and  bottom  of  the  cylinder,  by 
lifting  a  valve  in  the  steam  passage, 
called  an   equilibrinm  valve:  the 
pressures  on  the  pirton  are  thus 
equalized,  and  the  weight  acts  to 
force  the  water  up,  and  raise  the 
piston 
Comticopui,  or  horn  of  plenty:  among 
architects,  painters,  &c.,  it  is  repre- 
sented under  the  figure  of  a  large 
horn,   out    of  which  issue  fruit, 
flowers,  &c« 
Conikuy,  an  inference  or  deduction 
Cmmumdei   fvood,    the   produce   of 
Ceylon  and  the  coast  of  India,  is 
shipped  in  logs   and  planks  from 
Bombay  and  Madras ;  it  is  of  a  red 
hazel-brown  colour,  handsome  for 
iurmture  wood,  and  turns  well 
Corona,  the  members  constituting  the 
uppermost  of  the  three  divisions  of 
the  entablature  of  a  portico,  or  any 
other  building  iu  which  columns  are 
introduced:  this  division  is  termed 
cormee 
Corona,  that  flat,  square,  and  massy 
member  of  a  cornice,  more  usually 
called  the  drip  or  larmier,  whose 
situation  is  between  the  cymatium 
above  and  the  bed-moulding  below: 
its  use  is  to  carry  the  water  drop 
by  drop  from  the  bmlding 
Corporax  elothf  a  ^^^^^  cloth  or  nap- 
kin spread  upon  the  altar,  on  which 
the  host  and  ehalice  are  phiced  at 
the  mass  in  the  Catholic  service 
Corpge^aie,  a  covered  place  at  the 
entrance  to  a  churchyard,  intended 
to  shelter  the  corpse  and  mourners 

from  rain 
Corridor,  a  gallery  or  open  commum- 

cation  to  the  different  apartments 

of  a  house 
Corso,  the  nam*  givenbyVitruvinsto 


CORNISH  ENGINE. 


COT 


a  platband  or  square  fSsscia  whose 
height  is  more  than  its  projecture 

Cortile,  a  small  court  enclosed  by  the 
divisions  or  appurtenances  of  a 
building 

Cortig,  in  the  middle  aget^  a  court 
surrounded  by  edifices 

Coiyeeum,  a  room  similar  to  a  tennis- 
court 

Costean  pita,  in  Cornish  mining,  are 
shallow  pits  sunk  to  trace  or  find  tin 

Costeanmg,  in  mining,  the  discover- 
ing of  lodes  by  sinldng  pita  in  their 
vicinity,  and  drawing  transversely 
to  their  supposed  direction 

Cott  in  nautical  phraseology,  a  bed- 
frame  suspended  from  the  beams 
of  the  ship,  or  otherwise 

Cottony  a  white  woolly  or  downy 
substance,  found  in  a  brown  bud, 
produced  by  a  shrub,  the  leaves  of 
which  resemble  those  of  the  syca- 
moro-tre^.  The  bud,  which  grows 
as  large  as  a  pigeon's  egg,  turns 
black  when  ripe,  and  divides  at 
top  into  three  parts :  the  cotton  is 
as  white  as  snow,  and  with  the 
heat  of  the  sun  swells  to  the  size 
of  a  pullet's  egg.  Scripture  speaks 
of  cotton. 

Cotton  numufaeturet  and  trade.  Cot- 
ton was  woven  by  the  Hindoos  and 
Chinese  many  centuries  before  the 
Christian  era.  The  Egyptians  are 
supposed  to  have  imported  woven 
cotton  before  the  plant  had  begun 
to  be  cultivated  in  their  country ; 
and  the  Romans  received  woven 
cotton  from  India  long  before  the 
cotton-plant  was  known  in  Europe. 
The  extension  of  the  manufacture 
of  it  has  now  become  enormous. 
The  export  of  cotton  goods  from 
England,  m  1846,  was  £25,600,693 
in  value. 

Cotton  tphmmff:  the  spinning  of  cot- 
ton  into  the  form  of  yam  or  thread 
requires  many  preparatory  pro- 
cesses ;  but  the  inventions  and  im- 
provements in  machinery  that  have 
been  effected  in  recent  years  have 
rendered  the  process  simple  and  of 
great  national  value 

Cotton  and  CaUeo  printing,  the  art 


123 


COT 


COUNTRY  RESIDENCES. 


cou 


of  staining  woven  fabrics  of  cotton 
with  various  figures  and  colours 

Cotton  cultivation  and  trade.  The 
distinctive  names  by  which  cotton 
is  known  in  commerce  are  mostly 
derived  from  the  countries  which 
produce  it :  the  exceptions  are,  sea- 
island  cotton,  and  upland  cotton. 
The  former  of  these  was  first  cul- 
tivated in  the  low  sandy  islands 
near  the  coast  of  Charleston  in 
America ;  while  the  latter  is  grown 
in  the  inner  or  upland  country. 
The  sea-island  cotton  is  the  finest 
of  the  several  varieties.  The  upland 
is  often  called  Bowed  Cotton. 

Cottony  gun,-  is  prepared  with  cotton 
wool,  and  explodes  at  400®  Fahr. 
Gunpowder  explodes  at  600® 

Couched,  laid  close,  as  in  a  stratum 

Comsgmet.    (See  Coniamnet,) 

Coulisse,  any  piece  of  timber  which 
has  grooves  in  it;  also  pieces  of 
wood  which  hold  the  floodgates  in 
a  sluice 

Counter,  that  part  of  a  vessel  between 
the  bottom  of  the  stem  and  the 
wing  transom  and  buttock 

Counterfort,  a  pier,  buttress,  or 
oblique  wall,  built  up  against  a  wall 
to  strengthen  and  support  it 

Counter'ffttUffe,  in  carpentry,  a  method 
of  measuring  joints  by  transferring 
the  breadth  of  a  mortise  to  the 
place  on  another  timber  where  the 
tenon  is  to  be  made 

Counter»lath,  in  tiling,  a  lath  placed 
by  the  eye 

Counterpoise,  any  weight  which, 
placed  in  opposition  to  another 
weight,  produces  an  equilibrium; 
but  it  is  more  commonly  used  to 
denote  the  weight  used  in  the  Ro- 
man balance,  or  steelyard 

Countersinks,  in  joinery,  are  bits  for 

widening  the  upper  part  of  a  hole 

in  wood  or  iron,  for  the  head  of  a 

screw  or  pin,  and  have  a  conical 

head.    Those  for  wood  have  one 

cutter  in  the  conic  surface,  and 

have  the  cutting  edge  more  remote 

from  the  axis  of  the  cone  than  any 

other  part  of  the  surface.    Coun- 

tersinks  for  brass  have  eleven  or 
_  _ 


twelve  cutters  round  the  conic  sur- 
face, so  that  the  horizontal  section 
represents  a  circular  saw.  These 
are  called  rose-countersinks.  The 
conic  angle  at  the  vertex  is  about 
90  degrees.  Countersinks  for  iron 
have  two  cutting  edges,  forming  an 
obtuse  angle. 

Count'house,  a  reckoning-house,  in 
Derbyshire ;  a  house  or  room  on 
the  mine  used  for  keeping  accounts 
of  the  products,  &c 

Country  residences.  There  are  im- 
portant advantages  which  deserve 
to  be  brought  into  notice,  whether 
for  comfort  and  convenience,  for 
gp*atifying  taste  or  fashion.  Addi- 
tional  rooms  appropriated  for  ne'w 
purposes  are  often  requisite.  For- 
merly  a  gallery,  although  there  were 
no  works  of  art  to  fill  it,  was  a  ne- 
cessary part  of  a  mansion ;  of  late 
years,  the  billiard-room  and  the 
conservatory  enter  into  the  arrange- 
ments of  an  architect ;  and  a  suit 
of  well-planned  nursery-rooms  have 
been  made  a  necessary  part  of  the 
plan  of  a  country  mansion.  The 
gallery  is  again  about  to  resume 
its  importance,  and  perhaps  we  may- 
hereafter  imitate  the  Romans  in 
having  covered  walks  contiguous 
to  the  house,  in  order  to  enjoy 
fresh  air  in  the  many  rainy  and 
snowy  days  at  a  country  residence 
in  an  En^ish  winter.  The  irregu- 
lar  style  admits  of  such  additions, 
and  loses  nothing  of  the  picturesque 
effect.  The  exterior  decorations  of 
terraces,  parterres,  stairs  of  com- 
munication, and  different  gardens 
filled  with  groups  of  the  many  flow- 
ery shrubs  andplants,  are  admirably 
in  harmony  with  this  style  of  archi. 
tecture.  While  we  thus  decorate 
closely  around  the  house,  it  becomes 
less  necessary  to  sacrifice  so  much 
to  the  park.  The  masonry  of  such 
irregular  architecture  requires  not 
the  expensive  labour  bestowed  on  a 
Grecian  or  Roman  mansion.  The 
whole  should  be  in  rough  nibble- 
work,  excepting  the  parapets,  the 
comers,  the  windows,  and  doors. 


cou 


COUPLINGS. 


COV 


Many  yery  good  designs  of  castel- 
lated dwellings  have  been,  in  the 
execution,  deprired  of  their  effect, 
by  being  built  of  smooth,  hewn  free- 
stone. If  circular  or  square  towers 
are  introduced  in  a  composition  of 
the  irregular  style,  they  should,  in 
every  case,  be  of  great  dimensions, 
as  much  for  their  being  applied  to 
useful  rooms,  as  to  produce  that 
grandeur  of  appearance  which  bulk 
in  towers  always  gives. 

Cmmtry  seat9^\Le)  (^ the  Italians  have 
been  copied  by  most  civilized  na- 
tions of  Europe;  oelebratedbypoets, 
visited  and  admired  by  travdlers : 
they  have  not,  however,  been  de- 
scribed or  represented  as  they  de- 
serve. They  are  so  arranged  as  to 
produce  the  best  effect,  and  ad- 
vantage of  the  nature  of  the  site 
has  been  taken  with  admirable  skill. 
The  regularities  of  the  gardens  ac- 
company the  decoration,  and  sup- 
porttbe  architecture.  (See  Parker's 
'ViUaRnstica,'  recently  published.) 

Couple-dotef  a  pair  of  spars  of  a  roof; 
also  used  by  heralds  as  a  diminu- 
tive of  the  chevron 

Cwpkd  cokimns^  When,  from  the 
extent  between  columns  sometimes 
necessary  for^the  introduction  of 
doors,  windovra,  niches,  or  other 
decorations,  neither  the  eustylos 
nor  the  diastylos  interoolumniation 
canbe  used,  coupledoolumns  are  fre- 
quently introduced.  In  this  case  two 
sistylosintercolumniations  are  used ; 
the  column  which  would  otherwise 
occupy  the  middle  of  the  space  being 
brought  to  the  distance  of  only  half 
a  diameter  (or  sufficient  room  for 
the  projection  of  the  capitals)  from 
the  extreme  column.  The  middle 
space  will  then  be  three  diameters 
and  a  half.  This  species  has  been 
called  aneosistylos.  When  buildings 
are  small,  the  interoolumniations 
will  not  require  such  particular  at- 
tention to  the  foregoing  rules,  for 
colnmus  should  never  be  placed 
nearer  to  each  other  than  3  feet, 
which  will  allow  for  the  easy  pas- 
^aige  of  a  bulky  person. 


CoupHnfft  in  machinery,  is  the  name 
given  to  various  arrangements  by 
which  the  parts  of  a  machine  may 
be  connected  or  disconnected  at 
pleasure,  or  by  which  a  machine 
may  be  disengaged  from,  or  re- 
engaged with,  a  revolving  wheel  or 
shaft,  through  which  it  receives 
motion  from  a  steam  engine,  water- 
wheel,  or  other  prime  mover 

CoupUngs^  in  mill-work:  it  is  fre- 
quently necessary  to  convey  motion 
much  farther  than  would  be  prac- 
ticable by  any  one  shaft,  and  there- 
fore often  requisite  to  connect  two 
or  more  shaifts  together.  These 
connections  are  denominated  coup- 
lings, and  may  be  divided  into  two 
classes :  1  st.  Those  having  two  bear- 
ings; 2ndly,  Those  having  one  bear- 
ing. Couplings  having  two  bearings 
have  been  long  in  use,  and  before 
those  having  one  bearing,  and  are 
generally  more  simple  in  their  con- 
struction. 

Cmgff1mg4MMPt  ft  metal  box  for  joining 
the  ends  of  two  shafts,  so  that  they 
may  revolve  together 

Coune-,  a  continuous  range  of  stones 
or  bricks,  of  uniform  height,  in  the 
wall  of  a  building 

Courfe,  in  Cornish  mining,  is  a  tin 
or  copper  course ;  a  phrase  for  work- 
ing of  the  lode 

Cott>v69,  sails  that  hang  from  a  ship's 
lower  yards  :  the  fore-sail  is  called 
the  fore-course,  and  the  main-sail 
the  main-coarse 

Courts  of  Justice:  there  were  inRome 
twelve  halls  or  courts  of  justice, 
where  causes  were  heard  and  tried : 
they  were  adorned  with  statues, 
fine  columns,  and  porticoes  vrith 
double  rows  of  columns 

Covst  ft  cave,  a  recess ;  any  kind  of 
concave  moulding;  the  concavity 
of  an  arch  or  of  a  ceiling 

Coved  ceUmg,  the  upper  smf  ace  of  an 
apartment  formed  in  an  arched  or 
coved  shape  at  its  junction  with 
the  side  walls 

Covert  in  slating,  the  part  of  the  slate 
that  is  hidden ;  the  exposed  part 
being  called  the  margin 


125 


GOV 


CRANK. 


CRA 


Cover-way f  in  roofing,  the  recess  or 
internal  angle  left  to  receive  the 
covering 

Covie  or  Covey  t  a  pantry 

Covinffi  the  exterior  projection  of  the 
upper  parts  of  a  building  beyond 
the  limits  of  the  ground-plan 

Covinfff  a  term  applied  to  houses,  &c., 
that  project  over  the  ground-plot 

Coving  of  a  fire-place,  the  vertical  sides, 
inclining  backwards  and  inwards, 
for  the  purpose  of  reflecting  the 
heat 

Cowlj  a  cover  for  the  top  of  a  chim- 
ney, made  to  turn  round  by  the 
wind,  and  used  to  facilitate  the 
escape  of  smoke 

Coxswain^  the  person  who  steers  a 
boat,  and  has  charge  of  her 

Crabf  a  wooden  apparatus,  something 
like  a  capstan,butnot  furnished  with 
a  drum-head ;  it  is  used  for  similar 
purposes,  vnth  holes  made  to  insert 
the  bars 

Crabf  a  machine  with  three  claws, 
used  to  launch  ships,  to  heave  them 
into  the  dock,  or  off  the  quay 

Cradlef  a  frame  placed  under  the  bot- 
tom of  a  ship,  in  order  to  conduct 
her  steadily  into  the  water  when 
she  is  to  be  launched,  at  which  time 
it  supports  her  weight  while  she 
slides  down  the  descent  or  sloping 
passage,  called  the  ways,  which  are 
for  tlus  purpose  daubed  with  soap 
or  tallow 

Crafty  a  general  name  for  all  sorts  of 
vessels  employed  to  load  or  dis- 
charge merchant  ships,  or  to  carry 
alongside  or  return  the  guns,  stores, 
or  provisions  of  a  man-of-war:  such 
are  lighters,  hoys,  barges,  &c. 

Cramp,  a  short  bar  of  iron,  with  its 
ends  bent  so  as  to  form  three  sides 
of  a  parallelogram:  at  one  end  a 
set-screw  is  inserted,  so  that  two 
pieces  of  metal,  being  placed  be- 
tween, can  be  held  firmly  together 
by  the  screw 

Crane,  a  machine  used  for  hoisting  and 
lifting  stones,  ponderous  weights, 
and  heavy  goods,  principally  at 
wharfs  and  warehouses,  now  much 
employed  for  hoisting  heavy  build- 

126  '^ 


ing  materials;  also  as  travelling 
cranes  on  framed  scaffolding,  for 
the  Msistance  of  masons,  brick- 
layers,  and  other  artizans  in  build- 
ing,  saving  the  time  and  labour 
formerly  so  much  prolonged  in  the 
execution  of  the  work  to  be  done. 
(For  a  succinct  account  of  all  kinds 
of  cranes,  see  Glynn's  work  in  the 
'  Rudimentary  Series.' ) 

Cranes,  pieces  of  iron  or  timber  at  a 
vessel's  sides,  used  to  stow  boats 
or  spars  upon 

Crank,  the  condition  of  a  vessel  when 
she  is  inclined  to  lean  over  a  good 
deal,  and  cannot  bear  much  sail: 
this  may  be  ovring  to  her  construc- 
tion, or  to  her  stowage 

Crank,  the  arms  projecting  from  the 
main  shaft  of  an  engine,  joined  to- 
gether at  the  outer  ends 

Crank,  in  mechanics,  a  square  piece 
projecting  from  a  spindle,  serving 
by  its  rotation  to  raise  and  fall  the 
pistons  of  engines  t  it  also  denotes 
the  iron  support  for  a  lantern,  and 
the  iron  made  fast  to  the  stock  of 
a  bell 

Crank,  in  machinery,  is  a  bend  in  an 
axle,  by  which  a  reciprocating  mo- 
tion  in  a  rod  is  made  to  produce  a 
revolving  motion  of  an  axle  and  of 
a  wheel  which  may  be  connected 
with  it 

Crank,  in  turning,  that  part  of  the 
axle  of  the  fly  which  is  bent  into 
three  knees,  or  right  angles,  and 
three  projecting  parts :  one  of  the 
parts  is  parallel  to  the  axis,  and 
has  the  upper  part  of  the  crank- 
hook  collared  round  it 

Crank'iucle,  the  driving  axle  con- 
nected to  the  piston-rods  of  a  loco- 
motive engine 

Crank'hook,  in  turning,  sometimes 
also  called  the  connecting-rod,  as  it 
connects  the  treadle  and  the  fly 

Crank-pin,  the  cylindrical  piece  join, 
ing  the  ends  of  the  crank  arms, 
and  attached  to  the  connecting, 
rod,  or,  in  vibrating  engines,  to 
the  piston-rod:  if  the  crank  has 
only  one  arm,  the  pin  projects 
from  the  end  of  it 


CRA 


CROSS  (CHURCH). 


CRO  • 


Crayon,  a  chalk ;  a  species  of  mate- 
rial for  drawing.  Black  chalk, 
found  in  Italy,  wbite  chalk,  found 
in  France,  and  red  chalk,  form 
three  of  the  beat  varieties  of  cray- 
ons: each  has  its  own  peculiar 
value  as  a  drawing  material. 

Creazet,  in  mining,  the  work  or  tin 
in  the  middle  part  of  the  huddle  or 

dressing 

Credence,  the  small  table  at  the  side 
of  the  altar,  or  communion  table, 
on  which  the  bread  and  wine  were 
formerly  i^aced  before  they  were 
consecrated 

Creeper,  an  iron  instrument  like  a 
grapnel,  with  four  claws,  used  for 
dragging  the  bottom  of  a  harbour 
or  river,  to  find  any  thing  lost 

Crenelle^  the  embrasure  of  a  battle- 
ment, or  loophcdes 

Creffida,  according  to  Pliny,  any 
rused  basement  upon  which  other 
things  are  built  or  supported,  as  of 
a  temple,  altar,  obelisk,  &c. 

Cresset,  a  candlestick  or  lamp  to  con- 
tain  a  light 

Crest,  a  term  in  heraldry ;  the  orna- 
ment of  the  hehnet 

Creste,  the  ornamented  finishing  sur- 
rounding a  screen  or  canopy  of  a 

building  , 

CrestMleSf  those  used  to  cover  the 
ridge  of  a  roof,  upon  which  they  fit 
on  the  principle  of  a  saddle 

Crmale,  a  short  piece  of  rope  with 
each 'end  spliced  iuto  thebolt-rope 
of  a  sail,  confining  an  iron  ring  or 

thimble 
Criplwgs,  sliort  span  at  the  sides  of 

houses 

Crista,  a  crest ;  the  H>ex  or  highest 
part  of  a  shrine 

Crocket^  an  oniament  of  foliage  or 
animals  running  up  the  back  of  a 
pediment,  arch-pinnacle,  or  spire, 
from  the  corbels  below  to  the  finial 
above,  iu  which  latter  the  crockets 
on  both  sides  appear  to  merge 

Crockets,  projecting  leaves,  flowers, 
or  bunches  of  foliage,  used  in 
Gothic  architecture  to  decorate  the 
angles  of  spires,  canopies,  pinna- 

)      des,  Ac. 

lif 


Cromlech,  in  British  antiquity,  high, 
broad,  and  flat  stones,  raised  upon 
other  stones  set  on  end,  apparently 
for  the  purpose  of  an  altar 

Crcp,  ore  or  tin  of  the  first  quality, 
after  it  is  dressed  or  cleaned  for  * 
smelting 

Crosette,  a  truss,  or  console,  in  the 
flank  or  return  of  an  architrave  of 
a  door,  window,  or  other  aperture 
in  a  wall         | 

Crosettes,  in  decoration,  the  trusses 
or  consoles  on  the  flanks  of  the  ar- 
chitrave, under  the  cornice 

Cross,  a  gibbet  constructed  of  two 
pieces  of  wood  placed  transversely, 
whether  they  cross  each  other  at 
right  angles  at  the  top,  like  a  T, 
or  in  the  middle  of  their  length, 
like  an  X 

Cross,  the  symbol  of  the  Christian 
religion 

Cross,  cross  crusse,  cross  bar,  cross 
goffan,  cross  lode,  either  a  vein  of 
a  metallic  nature,  or  a  soft  earth, 
clay,  or  flookan,  like  a  vein,  which 
unheads  and  intersects  the  true 
lode 

Cross-bars,  round  bars  of  iron  bent 
at  each  end,  used  as  levers  to  turn 
the  shank  of  an  anchor 

CrosS'ChockSf  pieces  of  timber  fayed 
across  the  deadwood  amidships,  to 
make  good  the  deficiency  of  the 
heels  of  the  lower  futtocks 

Cross  (church),  or  a  Greek  cross,  that 
in  which  the  length  of  the  trans- 
verse part  is  equal  to  that  of  the 
nave;  so  called  because  most  of 
the  Greek  churches  were  built  in 
that  form 

Cross  (church),  or  a  Latin  cross,  that 
whose  nave  is  longer  than  the  cross 
part,  as  in  most  Gothic  churches 

Cross-grained  stuff,  in  joinery,  wood 
having  its  fibres  running  in  con- 
trary  positions  to  the  surfaces,  and 
which  consequently  cannot  be  made 
perfectly  smooth  when  planed  in 
one  direction,  without  turning  it  or 
turning  the  plane 

Cross-heads,  in  locomotive  engines, 
the  part  of  the  motion  into  which 
the  piston-rod  is  fitted  on  the  cy- 


CRO 


CRYPT. 


CRY 


Under  side  and  the  connecting-rod 
attached  on  th^riving  wheel  axle 
side 

Cross-head  guides^  in  locomotiye  en- 
gines, the  parallel  bars  between 
which  the  cross-head  moTCS  in  a 
right  line  with  the  cylinder  and 

.  driving  wheel  axle :  they  are  also 
called  motion  bars 

Cross-head  hhckSy  in  locomotive  en- 
gines, the  parts  which  slide  between 
the  parallel  guides.  The  ends  of 
the  cross-head  are  fitted  into  these 
blocks.  The  cross-head,  cross- 
head  guides,  and  block,  constitute 
what  is  called  '  the  motion  of  the 
engine.' 

Cross-heady  in  the  steam  engine,  a 
cross-bar  fixed  centrally  on  the  top 
of  a  piston-rod,  and  connected  to 
the  beam :  its  motion  is  confined 
to  a  direct  line  by  guides  at  each 
end;  or,  in  the  side-lever  and  beam 
engines,  by  an  apparatus  called  a 
<  parallel  motion' 

Cross-jack :  the  cross-jack  yard  is  the 
lower  yard  on  the  mizen  mast 

Cross-spaleSf  pieces  of  timber  placed 
across  a  vessel,  and  nailed  to  the 
frames,  to  keep  the  sides  together 
until  the  knees  are  bolted 

Cross-somerf  a  beam  of  timber 

Cross-springer^  in  groined  vaulting, 
the  rib  which  extends  diagonally 
from  one  pier  to  another 

Cross-trees^  pieces  of  oak  supported 
■by  the  cheeks  and  trestle-trees  at 
the  mast-heads,  to  sustain  the  tops 
on  the  lower  mast,  and  to  spread 
the  top-gallant  rigging  at  the  top- 
mast head 

Cross  vauUing  is  formed  by  the  inter- 
section of  two  or  more  simple 
vaults  of  arch-work 

Croud,  or  Crowde,  a  crypt,  or  under- 
croft of  a  church 

Craw,  in  mechanics,  an  iron  lever, 
made  with  a  sharp  point  at  one 
end,  and  two  claws  at  the  other; 
used  in  heaving  and  purchasing 
great  weights 

Crow-foot,  a  number  of  small  lines 
rove  through  to  suspend  an  awning 

Crown,  in  geometry,  a  plane  ring  in- 

128 


eluded  between  two  concentric 
perimeters,  generated  by  the  mo- 
tion of  part  of  a  right  line  round 
the  centre,  to  which  the  moving 
part  is  not  contiguous 
Crown  of  an  anchor,  the  place  where 
the  arms  are  joined  to  the  shank 

Crown  of  an  arch,  that  line  or  point 
upon  its  surface  which  is  the 
highest  or  most  elevated  from  its 
springing 

Crown-post,  the  middle  post  of  a 
trussed  roof 

Crown-wheeb.  Circular  motion  is 
communicated  at  right  angles  by 
means  of  teeth  or  cogs  situated 
parallel  to  the  axis  of  the  wheel. 
Wheels  thus  formed  are  denomi- 
nated 'crown'  or  *contrate  wheels:' 
they  act  either  upon  a  common 
pinion  or  upon  a  lantern. 

Crozier,  the  pastoral  staff  of  a  bishop 
or  mitred  abbot,  having  the  head 
curled  round  somewhat  in  the  man- 
ner of  a  shepherd's  crook 

Craciflx,  a  representation  of  our 
blessed  Saviour  on  the  cross 

Crustm,  figures  or  images  in  low 
relief,  embossed  upon  plate 

Crustarius,  an  artist;  an  engraver  for 
inlaid  work,  &c. 

Crutch,  a  knee  or  piece  of  knee 
timber,  placed  inside  a  vessel  to 
secure  the  heels  of  the  cant-tim- 
bers abaft 

Cryophorus,  an  instrument  by  which 
the  freezing  qualities  of  the  atmo- 
sphere may  be  ascertained 

Crypt,  a  vault  beneath  a  building, 
either  entirely  or  partly  under- 
ground, frequently  under  churches 
and  cathedrals 

Crypta,  or  Crypt,  among  the  Romans, 
any  long  narrow  vault,  whether 
wholly  or  partially  below  the  level 
of  the  earth 

Crypto  Portico,  an  enclosed  gallery 
or  portico  having  a  wall  with 
openings  or  windovrs  in  it,  instead 
of  columns  at  the  side 

Ctesibica  machina,  a  double-actioned 
forcing  pump  invented  by  Ctesibius 
of  Alexandria 

Cuare  (Cornish),  a  quarry  of  stones 


CUB 


CUPBOARDS. 


CUP 


Cnbahiref  the  cubing  of  a  solid,  or 
measuring  of  the    space  compre- 
hended in  a  Bolidy  as  in  a  cone, 
ppiunid,  cytinder,  &c. 
Cube,  in  geometry,  a  regular  or  solid 
body  consiatimg  of  six  square  and 
six  equal  faces  and  sides,  and  its 
angles    all    right,    and   therefore 
equal 
Cub€f  or  Heaeakedron,  a  solid  regular 
body,  consisting  of  ax  equal  square 
8idi» 
C^es,  or  Cube  wtmben  in  srithmetic, 
and  the  theory  of  numbers,  are 
tbose  whose  cube  root  is  a  com- 
plete integer ;  or  they  are  numbers 
produced  by  multiplying  a  given 
number  twice  into  itself,  or  by  the 
multiplication  of  three  equal  fac- 
tors 
Cvie  root^  of  a  number,  say  8,  the 
number  which  multiplied  into  itself 
twice  will  produce  8 — ^namely,  2 ; 
or  it  is  that  number  by  which,  if 
you  divide  a  number  twice,  the 
quotient  will  be  equal  to  itself 
Cyiic  foot  rf  wetter,  what  a  vessel 
1  foot  square  and  1  fdot  deep  will 
hold 
Oubieule,  among  the  Ronians,  a  bed- 

chsmber,  tent,  or  balcony 
CvHeulunut    according   to  Pliny,   a 
room  furnished  vnth  a  sofa  or  bed 
Cii^t^,  the  ground-work  or  lowest 

course  of  stones  in  a  budding 
Cvbit,  a  measure  used  among  the 
ancients,  and  which  the  Hebrews 
call  'amma,'  the  mother  of  other 
measures.  A  cubit  was  originally 
the  distance  from  the  elbow  to  the 
extremity  of  the  middle  finger; 
which  is  the  fourth  part  of  a  well- 
proportioned  man's  stature. 
Cubital,  a  bolster  or  cushion  for  the 

elbow  to  rest  upon,  for  invalids 
Cuioeh,  a  name  for  the  unit  or  in- 
teger of  a  power,  being  the  effect 
produced  by  one   cuMc  foot  of 
water  in  one  foot  perpendicular 

descent 
Cuekold'tJMckf  a  knot  by  which  a 
a  rope  is  secured  to  a  spar,  the 
two  parts  of  the  rope  crossing 
each  other  and  seized  together 

129  F  5 


Cuddy,  a  cabin  in  the  fore  part  of  a 
boat  -^ 

CuUig,  a  gutter  in  a  roof;  any  groove 
or  channel 

Culm,  stone  coal,  resembling  the  Kil- 
kenny coal  of  Ireland 

Culmen,  the  roof  of  a  house  or 
church 

Cuherhoute,  a  dove-cot  or  pigeon- 
house 

Cuhert,  an  arched  drain  for  the  pas- 
sage of  water 

Culvert,  an  arched  passage  or  bridge 
beneath  a  road,  canal,  or  railway 

CuheT'taU,  to  dove-tail 

Cuneua,  the  division  of  the  audience 
part  of  a  theatre  comjN^hended 
between  two  adjoining  scalaria  or 
staircases  which  lead  from  one 
precinctio  to  another:  so  called 
from  its  form,  which  resembles  a 
wedge.  The  foremost  cunei  were 
termed  '  cave  prima  ;*  the  middle, 
'  cavie  media ;'  and  the  uppermost, 
'cavsB  summa.'  The  whole  of 
the  audience  part,  exclusive  of 
the  orchestra,  was  likewise  called 
*caviB/ 

Cupboards  answered  in  some  respects 
to  the  sideboards  of  the  pre- 
sent day.  They  were  sometimes 
mere  planched  tops,  resting  on 
trestles,  or  fixed  with  legs  against 
the  wall ;  at  others,  framed  on 
stages,  rising  one  above  another, 
and  moveable:  these  were  called 
*  joined  cupboards,'  occasionally 
carved,  and,  like  tables,  covered 
vrith  carpets.  At  the  marriage  of 
Prince  Arthur,  son  of  Henry  VIL, 
in  the  hall  was  a  triangular  cup- 
board, five  stages  high,  set  with 
plate,  valued  at  JS1200,  entirely 
ornamental ;  and  in  the  **  utter 
chamber,"  where  the  princess 
dined,  was  another  cupboard,  *'  set 
with  gold  plate,  garnished  with 
stone  and  pearl,"  and  valued  at 
£20,000. 

Cupola,  a  small  room,  either  circular 
or  polygonal,  standing  on  the  top 
of  a  dome :  by  some  it  is  called 
a  lantern 

Cupola,    a  spherical   or    spheroidal 


CUP 


CYCLOIDAL  CURVES. 


CYC 


covering  to  a  building,  or  any  part 
of  it 

Cvp'Vidve,  for  a  steam«engine :  it  re- 
sembles a  conical  valve,  made  to  fit 
a  cover  in  the  form  of  a  vase  or  of 
the  portion  of  a  sphere 

Curia,  in  architecture ;  the  building 
in  v?hich  the  highest  council  of 
the  Roman  state  assembled,  des- 
cribed by  Vitruvius  as  being  ad- 
jacent to  the  agora  or  forum 

Curling-stuff,  in  joinery,  that  which 
is  produced  by  the  winding  or 
coihng  of  the  fibres  round  the 
boughs  of  a  tree,  when  they  begin 
to  shoot  out  of  the  trunk 

Current  y  a  stream  or  flux  of  water  in 
any  direction.  The  setting  of  the 
current  is  that  point  of  the  com- 
pass towards  which  the  waters 
run ;  and  the  drift  of  a  current  is 
the  rate  it  runs  per  hour. 

Curtilage,  a  term  formerly  applied  to 
the  division  or  boundaiy  of  manor- 
ial lands 

Curve,  in  geometry,  a  line  wherein 
the  several  points  of  which  it  con- 
sists tend*  several  ways,  or  are 
posited  towards  different  quarters 

Curvilinear,  consisting  of  curved  lines 

Cushion-capital,  the  capital  of  a  co- 
lumn so  sculptured  as  to  resemble 
a  cushion  pressed  down  by  the 
weight  of  its  entablature 

Cushiomt  and  unudow-piUows  were,  in 
Tudor  times,  stuffed — not  unlike 
the  woolsack  of  the  lord  chancellor 
— ^in  round,  square,  and  oblong 
shapes,  covered  with  carpet-work, 
velvet,  or  embroidery;  the  family 
armsfrequentlysupplyingthe  device 

Cuip,  an  ornament  generally  in  Gothic 
windows  or  doors :  it  is  to  be  found 
in  the  concave  bends  of  stone-work 

Cusps,  projecting  points  forming  the 
featherings  or  foliation  in  Gothic 
tracery,  archery,  panels,  &c. 

Cut,  in  mining,  to  intersect  a  vein, 
branch,  or  lode,  by  driving  hori- 
zontally or  sinking  perpendicularly 
at  right  angles 

Cutter,  a  small  boat ;  also  a  kind  of 
sloop 

Cutting.    Cutting  instruments  act  in 

130 


dividing  bodies  upon  the  same 
principle  as  the  wedge.  The  blade 
of  the  instrument  is  in  general  a 
thin  wedge,  but  the  edge  itself  is 
usually  much  more  obtuse. 

Cutwater,  in  a  ship,  is  the  sharp  part 
of  the  head  under  the  beak  or  figure 

Cycle,  a  round  of  time ;  a  space  in 
which  the  same  revolution  begins 
again ;  a  periodical  space  of  time 

Cycle,  bmar,  a  period  of  nineteen 
years 

Cycle,  solar,  a  period  of  twenty-eight 
years,  after  which  the  days  of  the 
month  return  to  the  same  days  of 
the  week 

Cyclograph,  or  Arcograph,  an  instru- 
ment for  drawing  arcs  oi  circles 
without  centres,  used  in  architec- 
tural and  engineering  drawings 
when  the  centres  are  too  distant 
to  be  conveniently  accessible 

Cycloidal  curves  are  defined  as  fol- 
lows :  1.  When  a  circle  is  made  to 
rotate  on  a  rectilinear  basis,  the 
figure  described  on  the  phme  of 
the  basis  by  any  point  in  the  plane 
of  the  circle  is  called  a  trochoid : 
a  circle  concentric  with  the  gene- 
rating circle,  and  passing  through 
the  describing  circle.  2.  If  the 
describing  point  is  in  the  circum- 
ference of  the  rotating  circle,  the 
two  circles  coincide,  and  the  curve 
is  called  a  cycloid.  3.  If  a  circular 
basis  be  substituted  for  a  rectilinear 
one,  the  trochoid  will  become  an 
epitrochoid,  and  the  cycloid  an 
epicycloid.  . 

Cyelopian  Architecture,  a  class  of 
building  supposed  to  have  preceded 
the  invention  of  the  classic  orders 
in  Greece,  and  attributed  to  the 
Cvclones 

Cyclopean  wall,  the  oldest  example  of 
mason-work  in  Italy :  in  town-walls 
only  has  this  style  of  building  bewi 
used.  The  history  of  its  origin  is 
obscure.  A  large  irregular  mass 
of  stone,  having  three,  four,  five, 
or  more  sides,  hew  only  on  >m 
irregular  sides  to  be  buUt  upon, 
begins  a  wall ;  to  this  mass  others 
are  added,  the  sides  of  which  arc 


I      CYC 


CYMA,  DADO. 


CYZ 


made  to  fit  the  irregular  tides  of 
the  first  block ;  and  on  these  again 
others  of  similar  forms  are  built  in 


the  same  manner. 
Cyclostylar,  relating  to  a  stmcture 
composed  of  a  circnlar  range  of 
colmnns  without   a  core;  with  a 
core,  the  range  would  be  a  peristyle 

Cylinder,  a  body  having  two  flat  sur- 
faces and  one  drcidar:  for  in- 
stance, a  roller  is  a  cylinder 

Cylinder,  a  roller  used  for  levelling  and 
condensating  the  ground  in  agri- 
cultural and  other  operations 

Cylinders,  in  steam  engines,  hollow 
cylindrical  vessels  :  within  the  cy- 
linder the  steam  exerts  its  power 
upon  the  piston,  which,  by  means 
of  its  rod,  transmits  it  to  the 
other  parts  of  the  engine 

Cylinders,  in  locomotive  engines, 
hollow  vessels,  usually  made  of  cast 
iron,  and  bored  out  accurately,  into 
which  pistons  are  fitted  steam- 
tight,  yet  easily  moveable  by  the 
pressure  of  the  steam 

Cylinder  coeks^  in  steam  engines, 
cocks  placed  in  coBvenient  parts 
of  the  cylinder  for  admitting  oil  to 
lubricate  the  piston,  or  by  which 
to  blow  out  the  condensed  steam, 
or  any  deposit  in  the  cylinders 

CyUnder  cover,  in  steam  engines,  the 
lid  bolted  to  a  flanch  round  the  top 
of  a  cylinder,  so  as  to  be  perfectly 
steam-tight :  tt  has  a  stuffing-box 
cast  in  the  centre,  through  which 
the  piston-rod  alternates 

Cylindrical  vauU^  a  vault  without 
groins,  resting  upon  two  parallel 
walls 


DAC 

DACTYI.U8,  aGreek  measure  of  length, 
the  sixteenth  part  of  an  English  foot 

Bado,  a  term  for  the  die  or  plane 
face  of  a  pedestal.  The  dado  em- 
ployed in  the  interior  of  buildings 
is  a  continuous  pedestal,  with  a 
plinth  and  base  moulding,  and  a 
oomice  or  dado  moulding  sur- 
mounting the  die, 
^____     1 1-         ' 

131 


Cylindrical  walling  is  that    erected 
upon  a  circular  plan,  forming  a 
cylinder,  or  a  part  less  than  a  cy- 
linder, according  as  the  plan  is  an 
entire  circumference  or  a  less  por- 
tion 
CyUnff,  anciently  ceiling, 
Cymot  called  also  cymaiium,  its  name 
arising  from  its  resemblance  to  a 
wave ;  a  moulding  which  is  hollow 
in  its  upper  part,  and  swelling  be- 
low.    There  are  two  sorts, —  the 
Cyma  recta,  just  described,  and 
the   Cyma  reversa,  whose  upper 
part  swells,  whilst  the  lower  part 
is  hollow. 
Cymatium,  a  moulding  whose  section 
or  profile  is  convex  below  and  con- 
cave above,  somewhat  resembling 
the  letter  S 
Cymophane,  a  mineral  of  a   green 
colour,  resembling  the  chrysoberyl 
Cypress-tree,  one  of  the  evergreens ; 
very  proper  to  mix  with  pines  and 
firs  in  forming  clumps.     The  wood 
of  the  cypress  is  very  valuable, 
when  grown  to  a  size  fit  for  planks, 
which  dimension   it  attains  in  as  { 
short  a  time  as  oak.     It  was  much  > 
used  by  the  ancients,  and  was  em- 
ployed in  the  original  doors  of  St. 
Peter's  at  Rome,  which,  on  being 
replaced,  after  six  hundred  years, 
by  gates  of  brass,  were  found  to  be 
perfectly  free  from  decay,  and  with- 
in to  have  retained  part  of  the  ori- 
ginal odour  of  the  wood. 
Cyrtostyle,  a  circular  projecting  por- 
tico 
Cyzicenus,  anciently  a  hall  decorated 
with  sculpture 


{. 


DAD 


Dado,  the  solid  block  or  cube  forming 
the  body  of  a  pedestal,  in  clossicrJ 
architecture,  between  the  base 
mouldings  and  cornice;  an  archi- 
tectural arrangement  of  mouldings, 
&c.  round  the  lower  part  of  the 
walls  of  a  room 

Dagger,  in  ship-building,  a  piece  of 
timber  that  crosses  all  the  poppets 


DAG 


DATA. 


DAT 


of  the  bulge-ways,  to  keep  them 
together:  the  phink  that  secures 
the  heads  of  the  poppets  is  called 
the  dagger-plank 

Dagger  knees  are  lodging  knees,  with 
side  arms  cast  down  and  bolted 
through  the  clamp :  they  are  placed 
at  the  lower  decks  of  some  ships, 
instead  of  hanging  knees,  to  pre- 
serve as  much  stowage  in  the  hold 
as  possible 

Dairy-houee,  a  place  for  keeping  milk 

Daist  in  early  domestic  architecture, 
the  chief  seat  at  the  high  board  or 
principal  table  (cross-table)  in  a 
baronial  hall;  also  the  principal 
table  itself,  and  the  raised  part  of 
the  floor  on  which  it  is  placed 

DaiSf  a  canopy  to  cover  an  altar, 
throne,  or  tribunal ;  the  chief  or 
upper  table  in  a  monastery 

Dam,  a  bank  or  obstruction  built 
across  a  river  or  stream,  for  the 
purpose  of  raising  the  level  of  the 
water  on  the  upper  side  of  it. 
Dams  built  for  the  purpose  of  in- 
land navigation,  or  for  that  of  se- 
curing a  water  power,  may  be  con- 
sideredas  having  a  more  permanent 
charactl^. 

Damascue  eteeh  a  sort  of  steel  brought 
from  the  Levant,  greatly  esteemed 
for  the  manufacture  of  cutting  in- 
struments 

Damaeguinef  a  term  applied  to  orna- 
mental work  of  gold  or  silver,  in- 
crusted  on  iron  or  steel 

DamorUco  or  Moniconf  an  iron  ochre, 
being  a  compound  of  terra  di  sienna 
and  Roman  ochre,  burnt,  and  hav- 
ing all  their  qualities  :  it  is  rather 
more  russet  in  hue  than  the  orange 
de  Mars,  has  considerable  transpa- 
rency, is  rich  and  durable  in  colour, 
and  affords  good  flesh  tints 

Damper  t  a  valve  placed  in  a  chimney, 
to  diminish  the  draught  when  the 
heat  is  too  intense 

Damper t  in  locomotive  engines,  a  kind 
of  iron  Venetian  blind,  fixed  to  the 
smoke-box  end  of  the  boiler,  in 
front  of  the  tubes :  it  is  shut  down 
when  the  engine  is  standing,  and 
thus  stops  the  draught  and  econo- 

132 


mizes  fuel ;  but  it  is  opened  when 
the  engine  is  running 

Damps :  various  kinds  of  permanently 
elastic  fluids  generated  in  mines 
are  thus  named  by  the  miners : 
choke-damps  consist  mostly  of 
carbonic  acid  gas,  and  fire-damps 
of  carburetted  hydrogen  gas 

Dancette,  in  heraldry,  zigzag  or 
chevron  fret;  seen  in  Nonnan 
buildings 

Data  us^fiil  in  various  calculations  of 
the  properties  of  materials.  [The 
data  correspond  to  the  mean  tern- 
perature  and  pressure  of  the  atmo- 
sphere ;  the  materials  are  assumed 
to  be  dry,  and  the  temperature  is 
measured  by  Fahrenheit's  scale.] 

Air.  Specific  gravity,  0*0012  ; 
weight  of  a  cubic  foot,  0*0753  lb., 
or  527  grains  (Shuckburgh) ;  13*3 
cubic  feet,  or  17  cylindiic  feet  of 
air,  weigh  1  lb. ;  it  expands  -^^  or 
•00208  of  its  bulk  at  32''  by  the 
addition  of  one  degree  of  heat 
(Dulong  and  Petit). 

Ash.  Specific  gravity,  0*76  ; 
weight  of  a  cubic  foot,  47*5  ibs. ; 
weight  of  a  bar  1  foot  long  and  1 
inch  square,  0*33 ft.;  will  bear 
VTithout  permanent  alteration  a 
«  strain  of  3540  fts.  upon  a  square 
inch,  and  an  extension  of  ^^  ofi  its 
length ;  weight  of  modulus  of  elas- 
ticity for  a  base  of  an  inch  square, 
1,640,000 fts.;  height  of  modulus 
of  elasticity,  4,970,000  feet ;  mo. 
dulus  of  resilience,  7*6;  specific 
resilience,  10.  (Calculated  frt>zii 
Barlow's  experiments.) 
Compared  with  cast  iron  as  unity, 
'  its  strength  is  0*23 ;  its  extensibi. 
lity,  2*6 ;  and  its  stiffiiess,  0*089. 

Atmosphkrb.  Mean  pressure  of  , 
at  London,  28*89  inches  of  mercury 
» 14*18  fts.  upon  a  square  inch. 
(Royal  Society.)  The  pressure  of 
the  atmosphere  is  usually  estimated 
at  30  inches  of  mercury,  which  is 
very  nearly  14f  fts.  upon  a  square 
inch,  and  equivalent  to  a  oolomn 
of  water  34  feet  high. 

Beech.  Specific  gravity,  0*696 ; 
weight  of  a  cubic  foot,  45*3  tbs. ; 


I  DAT 


I 


weight  of  a  bar  1  foot  long  and 
1  inch  square,  0*315  ib.;  will  bear 
without  permanent  alteration  on  a 
square  inch,  2360  lbs.,  and  an  ex- 
tension of  7^  of  its  length;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  1,345,000  fbg.; 
height  of  modulus  of  elasticity, 
4,600,000  feet ;  modulus  of  resi- 
lience, 4*14  ;  specific  resilience,  6. 
(Calculated  from  Barlow's  Experi- 
ments.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0'15  ;  its  extensibi- 
lity, 2-1;  and  its  stiffness,  0073. 

Brass,  cast.  Specific  gravity, 
8*37;  weight  of  a  cubic  foot,  523  ibs.; 
weight  of  a  har  1  foot  long  and 
1  inch  square,  3*63  tfes. ;  expands 
Tvlinr  o^  i^  length  by  one  degree 
of  heat  (Troughton);  melts  at  1869*^ 
(Daniell) ;  cohesive  force  of  a  square 
inch,  18,000  ibs.  (Rennie);  will  bear 
on  a  square  inch  without  perma- 
nent alteration,  6700  lbs.,  and  an 
extension  in  length  of  1797;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  8,930,000  ibs. ; 
height  of  modulus  of  elasticity, 
2,460,000  feet;  modulus  of  resi- 
lience, 5 ;  specific  resilience,  0*6 
(Tredgold). 

Compared  virith  cast  iron  as 
onity,  ita  strength  is  0*435;  its 
extensibility,  0*9 ;  and  its  stiffness, 
0*49. 

Baic le.  Specific  gravity,  1  '84 1 ; 
weight  of  a  cubic  foot,  1151b8. ; 
absorbs  -^  of  its  weight  of  water ; 
cohesive  force  of  a  square  inch, 
275  lbs.  (Tredgold) ;  is  crushed  by 
a  force  of  562  tbs.  on  a  square  inch 

(Rennie.) 

Brick-wobk.  Weight  of  a  cubic 
foot  of  newly  built,  1 1 7  tbs. ;  weight 
of  a  rod  of  new  brick-work,  16 

tons. 
Bridgss.      "When  a  bridge  is 

covered  with  people,  it  is  about 
equivalent  to  a  load  of  120  ibs.  on 
a  superficial  foot ;  and  this  may  be 
esteemed  the  greatest  possible  ex- 
traneous load  that  can  be  collected 
on  a  bridge  ;  whileone  incapable 


DATA.  DAT 

of  supporting  this  load  cannot  be 
deemed  safe. 

Bronze.    See  Cfun-metaL 

Cast  Iron.  Specific  gravity, 
7*207;  vreight  of  a  cubic  foot, 
450  lbs. ;  a  bar  1  foot  long  and  1 
inch  square  weighs  3*2  ibs.  nearly ; 
it  expands  Ytihnnr  ^  ^^  length  by 
one  degree  of  heat  (Roy) ;  greatest 
change  of  length  in  the  shade  in 
this  climate,  tt^*  greatest  change 
of  length  when  exposed  to  sun's  rays, 
T^;  melts  at  3479**  (Daniell), 
and  shrinks  in  cooling  from  -^  to 
■^  of  its  length  (Muschet);  is 
crushed  by  a  force  of  93,000  lbs. 
upon  a  square  inch  (Rennie) ;  w^ill 
bear  without  permanent  alteration, 
15,300  lbs.  upon  a  square  inch,  and 
an  extension  of  1^7  of  its  length ; 
weight  of  modulus  of  elasticity  for 
abase  linch  square,  18,400,000fbs.; 
height  of  modulus  of  elasticity, 
5,750,000  feet;  modulus  of  resi- 
lience, 12*7;  specific  resilience, 
1*76  (Tredgold). 

Chalk.  Specific  gravity,  2*315 ; 
weight  of  a  cubic  foot,  144*7  lbs. ; 
is  crushed  by  a  force  of  500  lbs.  on 
a  square  inch.   (Renni^ 

Clay.  Specific  gravity,  2*0 ; 
weight  of  a  cubic  foot,  125  lbs. 

Coal,  Newcastle,  Specific  gra- 
vity, 1*269 ;  weight  of  a  cubic  foot, 
79*31  tbs.  A  London  chaldron  of 
36  bushels  weighs  about  28  cwt., 
whence  a  bushel  is  87  lbs.  (but  is 
usually  rated  at  84  lbs.)  A  New- 
castle chaldron,  53  cwt.  (Smea- 
ton.) 

Copper.  Specific  gravity,  8*75 
(Hatchett) ;  weight  of  a  cubic  foot, 
549  lbs.;  weight  of  a  bar  1  foot  long 
and  1  inch  square,  3*81  lbs.;  ex- 
pands in  length  by  one  degree  of 
^eat,  ^ft^^gofl  (Smeaton) ;  melts  at 
2548®  (Daniell) ;  cohesive  foirce  of 
a  square  inch,  when  hammered, 
33,000  lbs.    (Rennie). 

Earth,  common.  Specific  gra- 
vity, 1*52  to  2*00;  weight  of  a 
cubic  foot,  from  95  to  125  tbs. 

Elm.  Specific  gravity,  0*544; 
weight   of  a  cubic  foot,   34  ibs. ; 


133 


DAT 


DATA. 


DAT 


weight  of  a  bar  1  foot  long  and  1 
inch  square,  0*236  tb.;  will  bear 
on  a  square  inch  without  perma- 
nent alteratioui  3240  lbs.,  and  an 
extension  in  length  of  ^f^;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  1,340,000  ibs.; 
height  of  modulus  of  elasticity, 
5,680,000  feet;  modulus  of  resi- 
lience, 7*87 ;  specific  resilience, 
14*4.  (Calculated  from  Barlow's 
Experiments.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*21 ;  its  extensi- 
bility, 2-9 ;  and  its  stiffness,  0*073. 

Fir,  red  or  yellow.  Specific  gra- 
vity, 0*557 ;  weight  of  a  cubic  foot, 
34*8  lbs. ;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  0*242 tb.; 
will  bear  on  a  square  inch  without 
permanent  alteration,  4290  lbs.  = 
2  tons  nearly,  and  an  extension  in 
length  of  -^j^ ;  weight  of  modulus 
of  elasticity  for  a  base  of  an  inch 
square,  2,016,000  tbs. ;  height  of 
modulus  of  elasticity,  8,330,000 
feet;  modulus  of  resUience,  9*13; 
specific  resilience,  16*4.  (Tred- 
gold.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*3;  its  extensibi- 
lity, 2*6,  and  its  stiffness,  0*1154, 

Fir,  white.  Specific  gravity,  0*4  7 ; 
weight  of  a  cubic  foot,  29*3  tbs. ; 
weight  of  a  bar  1  foot  long  and 
1  inch  square,  0*204  tb.;  will  bear 
on  a  square  inch  without  perma- 
nent alteration,  3630  tbs.,  and  an 
extension  in  length  of  -g^ ;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  1,830,000  lbs. ; 
height  of  modulus  of  elasticity, 
8,970,000  feet;  modulus  of  rest- 
lience,  7*2 ;  specific  resilience,  15*3. 
(Tredgold.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*23 ;  its  extensibi- 
lity, 2*4 ;  and  its  stiffness,  0*1. 

Floors.  The  weight  of  a  super- 
ficial foot  of  a  floor  is  about  40  tbs. 
when  there  is  a  ceiling,  counter- 
floor,  and  iron  girders.  When  a 
floor  is  covered  with  people,  the 

134 


load  upon  a  superficial  foot  may  be 
calculated  at  120 tbs.:  therefore, 
120  +  40:=  160  lbs.  on  a  superficial 
foot  is  the  least  stress  that  ought 
to  be  taken  in  estimating  the 
strength  for  the  parts  of  a  floor  of 
a  room. 

Force.  See  Gravity f  Horaet  &c. 

Granite,  Aberdeen,      Specific 

gravity,  2*625 ;  weight  of  a  cubic 

-foot,  164  tbs.;  is  crushed  by  a  force 

of  10*910  tbs.  upon  a  square  inch. 

(Rennie.) 

Gravel.  Weight  of  a  cabic 
foot,  about  120  lbs. 

Gravitt  generates  a  velocity 
of  32^  feet  in  a  second  in  a  body 
falling  from  rest;  space  described 
in  the  first  second,  16^  feet. 

Gun-metal,  cast  (copper  8 
parts,  tin  1).  Specific  gravity, 
8*153;  weight  of  a  cubic  foot, 
509i  lbs. ;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  3*54  tbs. 
(Tredgold) ;  expands  in  length  by 
V  of  heat,  ^^ll^  (Smeaton) ;  vdll 
bear  on  a  square  inch  without  per- 
manent alteration,  10,000  tbs.,  and 
an  extension  in  length  of  ^^ ; 
weight  of  modulus  of  elasticity  for 
a  base  1  inch  square,  9,873,000  tbs. ; 
height  of  modulus  of  elasticity, 
2,790,000  feet;  modulus  of  resi- 
lience,  and  specific  resilience,  not 
determined  (Tredgold). 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*65 ;  its  extensibi- 
lity, 1*25 ;  and  its  stiffness,  0*535. 

Horse,  of  average  power,  pro- 
duces the  greatest  effect  in  draw- 
ing a  load  when  exerting  a  force 
of  187itbs.  with  a  velocity  of  2i 
feet  per  second,  working  8  hours 
in  a  day.  (Tredgold.)  A  good 
horse  can  exert  a  force  of  480  tbs. 
for  a  short  time.  (Desaguliers.) 
In  calculating  the  strength  for 
horse  machinery,  the  horse's  power 
should  be  considered  400  tbs. 

Iron,  cast.    See  Cast  Iron, 

Iron,  malleable.  Specific  gravity, 
7*6  (Muschenbroek) ;  weight  of  a 
cubic  foot,  475  tbs. ;  weight  of  a 
bar  1  foot  long  and  1  inch  square. 


DAT 


DATA. 


DAT 


3'3  ibs. ;  ditto,  when  bammered, 
3-4  lbs.;  expands  in  length  by  l°of 
teat,  J4j|\mo  (  Smcaton ) ;  good 
English  iron  will  bear  on  a  square 
inch  without  permanent  alteration, 
17,800  ibs.  =  81  tons  nearly,  and  an 
extension  in  length  of  t^;  cohe- 
nve  force  diminished  ^^^  by  an 
elevation  1°  of  temperature;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  24,920,000  lbs. ; 
height  of  modulus  of  elasticity, 
7,550,000  feet ;  modulus  of  resi- 
lienoe,  and  speci'fie  resilience,  not 
determined  (Tredgold). 

Compared  with  cast  iron  as  unity, 
its  strength  is  1'12;  its  extensibi- 
lity,  0*86 ;  and  its  stiffness,  1*3. 

Larch.  Specific  gravity,  -560 ; 
weight  of  a  cubic  foot,  35  lbs. ; 
weight  of  a  bar  1  foot  long  and 
1  inch  square,  0*243  ib. ;  will  bear 
on  a  square  inch  without  perma- 
nent alteration,  2065  tbs.,  and  an 
extension  in  length  of  ^;  weight 
of  modulus  of  elasticity  for  a  base 
of  an  inch  square,  10,074,000  ibs. ; 
height  of  modulus  of  elasticity, 
4,415,000  feet;  modulus  of  resi- 
lience, 4 ;  specific  resilience,  7*1. 
(Calculated  from  Barlow's  Experi- 
ments.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*136 ;  its  extensi- 
bihty,  2*3 ;  and  its  stiffness,  0*058. 
Lead,  cast.  Specific  gravity, 
11*353  (Brisson)  ;  weight  oi  a 
cubic  foot,  709*5  ibs.;  weight  of  a 
bar  1  foot  long  and  1  inch  square, 
4-94  lbs. ;  expands  in  length  by  1^ 
degree  of  heat,  ,y^  (Smeaton)  ; 
melts  at  612**  (Crichton);  wiU 
bear  on  a  square  inch  without  per- 
manent alteration,  1500  ibs.,  and 
an  extension  in  length  of  ^; 
weight  of  modulus  of  elasticity  for 
a  base  1  inch  square,  720,000  ibs. ; 
height  of  modulus  of  elasticity, 
146,000  feet;  modulus  of  resi- 
lience, 3*12;  specific  resilience, 
0-27  (Tredgold). 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*096 ;  its  extensi- 
bility, 2*5 ;  and  its  stiffness,  0-0385. 


Mahogany, ^oiu/ura«.  Specific 
gravity,  0*56;  weight  of  a  cubic 
foot,  35  ibs.;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  0*243  tb. ; 
will  bear  on  a  square  inch  without 
permanent  alteration,  3800  ibs., 
and  an  extension  in  length  of  -^^ ; 
weight  of  modulus  of  elasticity  for 
a  base  1  inch  square,  1,596,000  tbs.; 
height  of  modulus  of  elasticity, 
6,570,000  feet;  modulus  of  resi- 
lience, 9*047;  specific  resilience, 
16*1.  (Tredgold.) 

Compared  with  cast  iron  as  unity, 
its  strength  is  0*24 ;  its  extensibi- 
lity, 2*9  ;  and  its  stiffness,  0*487. 

Man.  a  man  of  average  power 
produces  the  greatest  effect  when 
exerting  a  force  of  31^  tbs.  with  a 
velocity  of  2  feet  per  second,  for 
10  hours  in  a  day.  (Tredgold.)  A 
strong  man  will  raise  and  carry 
from  250  to  300  ibs.  (Desaguliers.) 

Marble,  white.  Specific  gra- 
vity, 2*706;  weight  of  a  cubic  foot, 
169  tbs. ;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  1*17  ib.; 
cohesive  force  of  a  square  inch, 
1811  tbs.;  extensibility,  7^^  of  its 
length ;  weight  of  modulus  of  elas- 
ticity for  a  base  of  an  inch  square, 
2,520,000 ibs.;  height  of  modulus 
of  ehisticity,  2,150,000  feet;  mo- 
dulus of  resilience  at  the  point  of 
fracture,  1*3 ;  specific  resilience  at 
the  point  of  fracture,  0*48  (Tred- 
gold); is  crushed  by  a  force  of 
6060  ibs.  upon  a  square  inch 
(Rennie). 

Mkrcurt.  Specific  gravity, 
13*568  (Brisson) ;  weight  of  a 
cubic  inch,  0*4948  lb.;  expands  in 
bulk  by  1""  of  beat,  -^^  (Dulong 
and  Petit) ;  weight  of  modulus  of 
elasticity  for  a  base  of  an  inch 
square,  4,417,000  tbs.;  height  of 
modulus  of  elasticity,  750,000  feet 
(Dr.  Young,  from  Canton's  Experi- 
ments). 

Oak,  good  EngUsh.  Specific 
gravity,  0*83;  weight  of  a  cubic 
foot,  52  tbs.;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  0*36 tb.; 
will  bear  upon  a  square  inch  with- 


135 


DAT 


DATA. 


DAT 


out  permanent  alteration,  3960  lbs., 
and  an  extensidtt  in  length  of  -^ ; 
weight  of  modulus  of  elasticity  for 
a  base  1  inch  square,  1,700,000 lbs.; 
height  of  modulus  of  elasticity, 
4,730,000  feet;  modulus  of  resi- 
lience, 9*2;  specific  resilience,  11. 
(Tredgold.) 

Compared  with  cast  iron  as 
unity,  its  strength  is  0*25;  its  ex- 
tensibility, 2'8;  and  its  stifihess, 
0-093. 

Pendulum.  Length  of  pendu- 
lum to  vibrate  seconds  in  the  lati- 
tude of  London,  391 372  inches 
(Kater);  ditto  to  vibrate  half- 
seconds,  9*7843  inches. 

Pine,  American  yellow.  Specific 
gravity,  0-46;  weight  of  a  cubic 
foot,  26f  tbs. ;  weight  of  a  bar 
1  foot  long  and  1  inch  square, 
0*186  tb.;  will  bear  on  a  square 
inch  without  permanent  alteration, 
3900  tbs., and  an  extension  in  length 
of  -^^ ;  weight  of  modulus  of  elas- 
ticity for  a  base  of  an  inch  square, 
1,600,000  ibs.;  height  of  modulus 
of  elasticity,  8,700,000  feet;  mo- 
dulus of  resilience,  9*4;  specific 
resilience,  20.  (Tredgold.) 

Compared  with  cast  iron  as 
unity,  its  strength  is  0*25 ;  its  ex- 
tensibility, 2*9;  and  its  stifhiess, 
0*087. 

Porphyry,  red.  Specific  gra- 
vity, 2*871 ;  weight  of  a  cubic  foot, 
179  ibs. ;  is  crushed  by  a  force  of 
35,568  lbs.  upon  a  square  inch. 
(Gauthey.) 

Rope,  hempen.  Weight  of  a 
common  rope  1  foot  long  and  1 
inch  in  circumference,  from  0*04 
to  0*46  !b. ;  and  a  rope  of  this  size 
should  not  be  exposed  to  a  strain 
greater  than  200  tbs. ;  but  in  com- 
pounded ropes,  such  as  cables,  the 
greatest  strain  should  not  exceed 
120  tbs.;  and  the  weight  of  a  cable 
1  foot  in  length  and  1  inch  in 
circumference  does  not  exceed 
0*027  tb.  The  square  of  the  cir- 
cumference in  inches  multiplied  by 
200  will  give  the  number  of  pounds 
a  rope  may  be  loaded  with ;  and 

lie 


multiply  by  120  instead  of  200  for 
cables.  Common  ropes  will  bear  a 
greater  load  ynth  safety  after  they 
have  been  some  time  in  use,  in  con- 
sequence of  the  tension  of  the  fibres 
becoming  equalized  by  repeated 
stretchings  and  partial  untwisting. 
It  has  been  imagined  that  the  im- 
proved strength  was  gained  by 
their  being  laid  up  in  store ;  but  if 
they  can  there  be  preserved  from 
deterioration,  it  is  as  much  as  can 
be  expected. 

Roofs.  Weight  of  a  squarefoot  of 
Welsh  rag  slating,!  l^tbs.;  weightof 
a  square  foot  of  plain  tiling,  1 6|-  lbs. ; 
greatest  force  of  the  wind  upon  a 
superficial  foot  of  roofing  may  be 
estimated  at  40  lbs. 

Slate,  Welsh,  Specific  gravity, 
2*752  (Kirwan) ;  weight  of  a  cubic 
foot,  1 72  tbs. ;  weight  of  a  bar  1  foot 
long  and  1  inch  square,  1*19  tb.  ; 
cohesive  force  of  a  square  inch, 
11,500 lbs.;  extension  before  frrac- 
ture,  Y^TTT*  weight  of  modulus  of 
elasticityfor  abase  of  an  inch  square, 
15,800,000  tbs.;  height  of  modulus 
of  elasticity,  13,240,000  feet;  mo- 
dulus of  resilience,  8*4 ;  speciiic  re- 
silience, 2  (Tredgold). 

Slate,  Westmoreland,  Cohe- 
sive force  of  a  square  inch,  7870  lbs. ; 
extension  in  length  before  fracture, 
t^4fl ;  weight  of  modulus  of  elas- 
ticity for  a  base  of  an  inch  square, 
12,900,000  lbs.  (Tredgold). 

Slate,  Scotch,  Cohesive  force 
of  a  square  inch,  9600  ibs. ;  exten- 
sion in  length  before  fracture,  t^^^-^  ; 
weight  of  modulus  of  elasticity  for  a 
base  1  inch  square,  15,790,000  lbs. 
'  (Tredgold). 

Steam.  Specific  gravity  at  2 1 2° 
is  to  that  of  air  at  the  mean  tem- 
perature as  0*4  72  is  to  1  (Thomson) ; 
weight  of  a  cubic  foot,  249  grains  ; 
modulus  of  elasticity  for  a  base  of 
an  inch  square,  I4f  tbs. ;  when  not 
in  contact  with  water,  expands  ^? 
of  itsbulkby  l°of  heat  (Gay-Lussac^ . 

Steel.  Specific  gravity,  7*84  ; 
weight  of  a  cubic  foot,  490  tbs. ;  a 
bar  1  foot  long  and  1  inch  square 


IDAT 


DATA. 


DAT 


weighs  3-4  ibs.;  it  expands  in  length 
by  1°  of  heat,  TyArr^r  (?oy);  tem- 
pered steel  wiU  beajr  without  per- 
manent alteration,  45,000  fts. ;  co- 
hesiye  force  of  a  square  inch, 
130,000  lbs.  (Rennie) ;  cohesive 
force  diminisfaed  stfo(T  ^7  elevating 
the  temperature  1°;  modulus  of 
elasticity  for  a  base  of  an  inch 
square,  29,000,000  fts. ;  height  of 
modulus  of  elasticity,  8,530,000  feet 
(Dr.  Young). 

Stonb,  Portland.  Specific  gra- 
vity, 2-113;  weight  of  a  cubic  foot,* 
132  fts. ;  weight  of  a  prism  1  inch 
square  and  1  foot  long,  0*92 ft.; 
absorbs  -^  of  its  weight  of  water 
(R.  Tredgold) ;  is  crushed  by  a 
force  of  3729  fts.  upon  a  square 
mch  (Rennie)  ;  cohesive  force  of  a 
square  inch,  857  fts. ;  extends  be- 
fore fracture  TTTff  ^^  ^^  length ; 
modulus  of  elasticity  for  a  base  of 
aninch  square,  1,533,000  fts.;  height 
of  modulus  of  elasticity,  1,672,000 
feet ;  modulus  of  resilience  at  the 
point  of  frtwjtture,  0-5 ;  specific  re- 
silience at  the  point  of  fracture, 
0-23  (Tredgold). 

Stonb,  Bath.  Specific  gravity, 
1-975;  weight  of  a  cubic  foot, 
123-4  fts.;  absorbs  -^  of  its  weight 
of  water  (R.  Tredgold);  cohesive 
force  of  a  square  inch,  478  lbs. 
(Tredgold). 

Stone,  Craiffleith.  Specific  grav- 
ity, 2-362 ;  weight  of  a  cubic  foot, 
147-f»fts.;  absorbs  ^  of  its  weight 
of  water;  cohesive  force  of  a  square 
inch,  7 72  fts.  (Tredgold);  is  crushed 
by  a  force  of  5490fts.  upon  a  square 
inch  (Rennie). 

Stone,  Dundee.  Specific  grav- 
ity, 2*621 ;  weight  of  a  cubic  foot, 
163-8  fts. ;  absorbs  y|y  part  of  its 
weight  of  water ;  cohesive  force  of 
a  square  inch,  2661  fts.  (Tredgold); 
is  crushed  by  a  force  of  6630  fts. 
upon  a  square  inch  (Rennie). 

Stonb-work-  Weight  of  a  cubic 
foot  of  rubble- work,  about  140  fts.; 
of  hewn  stone,  160  fts. 

Tin,  ca«^  Specific  gravity,  7*291 
(Brisson)  ;  weight  of  a  cubic  foot, 

137 


455*7  fts. ;  weight  of  a  bar  1  foot 
long  and  1  inch^quare,  3*165  fts. ; 
expands  in  length  by  1^  of  heat, 
ia\\^  (Smeaton);  melts  at  442^ 
(Urichton);  will  bear  upon  a  square 
inch  without  permanent  alteration, 
2880  fts.,  and  an  extension  in 
length  of  17^;  modulus  of  elas- 
ticity for  a  base  of  an  inch  square, 
4,608,000 ;  height  of  modulus  of 
elasticity,  1,453,000  feet ;  modulus 
of  resilience,  1 '8;  specific  resilience, 
0-247  (Tredgold). 

Compared  with  cast  iron  as  unity, 
its  strength  is  0-182 ;  its  extensibi- 
lity, 0*75 ;  and  its  stiffness,  0*25. 

Water,  rw<?r.  Specific  gravity, 
1*000;  weight  of  a  cubic  foot, 
62-5  fts. ;  weight  of  a  cubic  inch, 
252-525  grains ;  weight  of  a  prism 
1  foot  long  and  1  inch  square, 
0*434  ft. ;  weight  of  an  ale  gallon 
of  water,  10-2  fts.;  expands  in  bulk 
by  1°  of  heat,  -^^  (Dalton) ;  ex- 
pands, in  freezing,  -^  of  its  bulk 
(Williams);  andthe expandingforce 
of  freezing  water  is  about  35,000fts. 
upon  a  square  inch,  according  to 
Muschenbroek's  valuation;  modu- 
lus of  elasticity  for  a  base  of  an 
inch  square,  326,000  fts. ;  height  of 
modulus  of  elasticity,  750,000  feet, 
or  22,100  atmospheres  of  30  inches 
of  mercury  (Dr.  Young,  from  Can- 
ton's Experiments). 

Water  has  a  state  of  maximum 
density  at  or  near  40°,  which  is 
considered  an  exception  to  the 
general  law  of  expansion  by  heat : 
it  is  extremely  improbable  that  there 
is  any  thing  more  than  an  apparent 
exception,  most  likely  arising  from 
water  at  lowtemperatures  absorbing 
'  a  considerable  quantity  of  aur,  which 
has  the  efifect  of  expanding  it,  and 
consequently  of  causing  the  appa- 
rent anomaly. 

Water,  sea.  Specific  gravity, 
1-0271 ;  weight  of  a  cubic  foot, 
64-2  fts. 

Water  is  828  times  the  density 
of  air  of  the  temperature  60°,  and 
barometer  30. 

Whale-bone.    Specific  gravity, 


I 


DAT 


DEBRIS. 


DEB 


1-3 ;  wdg^  of  a  adnc  foot,  Slftc; 
wiUbeir  astninof  5600ftft.  upon 
a  sqoare  inch  witfaoai  pennanoit 
alteration,  and  an  cxtcnakMi  in 
lengith  of  yIt*  inodslos  of  das- 
fidtjr  for  a  base  of  an  inch  sqoare, 
820,000  fts. ;  hdgfat  of  modnlos  of 
elasticity,  1,458,000  feet ;  modulus 
of  resilience,  38*3 ;  specific  resili- 
ence, 29.   (Tredgold.) 

Wind.  Greatest  observed  Te- 
locity, 159  feetper  second  (Rochon); 
force  of  wind  with  that  velocity, 
about  57f  lbs.  on  a  square  foot. 

ZivccasL  Specificg;raTity,7'028 
(Watson) ;  weight  of  a  cuUc  foot, 
439ifts.;  weight  of  a  bar  1  inch 
square  and  1  foot  long,  3-05  fbs.; 
expands  in  length  by  1**  of  heat, 
vrkw  (Smeaton);  melto  at  648*" 
(Daniell);  will  bear  on  a  square 
inch  without  permanent  alteration, 
5700  lbs.  =  0-365  cast  iron,  and  an 
extension  in  length  of  ,^1^  =  ^that 
of  cast  iron  (lA^gold) ;  modulus 
of  elasticity  for  a  base  of  an  inch 
square,  13,680,000  lbs. ;  height  of 
modulus  of  elasticity,  4,480,000 
feet;  modulus  of  resilience,  2-4; 
specific  resiUence,  0*34  (Tredgold). 
Compared  with  cast  iron  as  unity, 
its  strength  is  0*365 ;  its  extensibi- 
lity,  0'5;  and  its  stiffness,  0*76 

Datat  a  term  for  such  facts,  things, 
or  quantities  as  are  given  or  known, 
in  order  thereby  to  find  other  things 
that  are  unknown 

Davit t  in  navigation,  a  short  boom 
fitted  in  the  fore  channel,  to  hoist 
the  flukes  of  the  anchor  to  the 
bow,  which  is  called  *  fishing  the 
anchor' 

Day  or  Bay^  in  architecture,  one  of 
the  lights  or  compartments  between 
mullion  and  mullion,  in  the  great 
windows  of  the  pointed  style 

DaySt  in  early  domestic  architecture, 
the  bay  or  Ughts  of  a  window;  the 
spaces  between  the  mullions 

Dead  colouring  is  the  first  layer  of 
colours,  consisting  usually  of  some 
shade  of  grey.  Its  design  is  to 
receive  and  preserve  the  finishing 
colours ;  and  it  is  called  dead  be- 


lt is  not  seen  when  the  work 
is  completed 

Dead  doort,  in  ship  buflding,  fitted  to 
die  outside  of  the  quarter-gallery 
doors,  in  case  the  quarter-gallery 
should  be  canied  away 

Dead  eyes,  fixed  in  the  channels,  with 
three  holes  to  receive  the  lanyard 
of  the  shrouds 

Dead  flat,  the  name  of  a  midship  board 

Dead  ligktMf  in  navigation,  wooden 
shutters  for  the  ad>in  windows, 
which  are  fostened  on  when  the 
sea  runs  high 

Dead  reckoning,  the  estimation  which 
seamen  nuke  of  the  ship's  place, 
by  keeping  an  account  of  her  way 
by  the  log,  by  the  course  steered, 
and  by  rectifying  the  whole  by  al- 
lowance for  drift,  leeway,  &c. 

Dead  shore,  a  piece  of  timber  worked 
up  in  brick-work,  to  support  a  su- 
perincumbent mass  until  the  brick, 
work  which  is  to  carry  it  has  set  or 
become  hard 

Dead  water,  the  eddy  water  imine- 
diately  at  the  stem  of  a  ship  while 
under  way 

Dead  wood,  pieces  of  timber  fayed 
on  the  keel  to  seat  the  flow-tim- 
bers  on  afore  and  abaft  the  floors 
and  continued  as  high  as  the  cutting 
down  of  the  floors 

Deaf ening  sound  boardingtthe  pugging 
used  to  prevent  the  passage  of  sound 
through  wooden  partitions 

Deam,  a  door-post,  or  threshold ;  to 
conceal,  or  shut  up 

Deambulatory,  an  ambulatory  or  clois- 
ter for  exercise ;  also  the  aisles  of 
a  church,  or  the  porticoes  round 
the  body  of  a  church 

Debacle,  a  great  aqueous  torrent,  a 
breaking  up  and  transport  of  mas- 
sive rocks  and  gravel  by  an  enor- 
mous rush  of  water 

Debris,  fragments  of  rocks,  boulders, 
gravel,  sand,  trunks  of  trees,  &c., 
detached  from  the  summits  and 
sides  of  mountains  by  the  eflfect  of 
the  elements 

Decade,  the  sum  of  ten 

Decagon,  in  geometry,  a  plain  figure 
of  ten  sides 


138 


DEC 


DEFINITIONS  IN  GEOMETRY. 


DEF 


Beealoffue,  the  Ten  Commandments 
delivered  to  the  Israelites  from 
Mount  Sinai,  in  'which  the  moral 
law  is  summarily  comprehended. 
The  Jews  call  these  precepts  *  The 
Ten  Words.'*  In  the  building  of 
new  churchesy  and  io  the  restora- 
tion of  those  of  olden  times,  a  pro- 
per and  effective  style  of  painting 
and  embellishing  the  words  of  the 
ten  commandments  in  face  of  the 
altar  has  been  introduced. 

DecanUnim,  an  ecclesiastical  prison 

Decastyle,  in  architecture :  a  temple 
is  said  to  be  decastyle  when  its  por- 
tico contains  ten  columns  in  a  line 

Decastyle,  a  portico  consisting  of  ten 
columns  in  front 

Decempeda,  a  ten-foot  rod  employed 
by  architects  and  surveyors  for 
taking  measurements 

Deeemremis,  a  vessel  with  ten  banks 
of  oars  on  a  side 

Decimal,  the  tenth  part 

Deck,  the  floor  of  a  ship 

Decoration,  the  combination  of  orna- 
mental objects  'which  are  employed 
m  great  Tariety,  principally  for  the 
interior  and  exterior  of  all  kinds 
of  edifices,  and  for  purposes  of  art 
generally.  Decoration,  when  judi- 
ciously introduced,  becomes  in 
many  instances  a  language,  intel- 
ligible only,  however,  when  the 
artist  is  capable  of  speaking  it 
correctly  and  the  spectator  of 
comprehending  it.  It  is  then  a 
system  of  hieroglyphic  writing, 
and  the  building  to  which  it  is  ap- 
pUed  becomes  historical,  and  tells 
its  tale  more  noUy  and  appro- 
priately than  it  can  ever  do  through 
the  tmdignified  medium  of  mural 
inscriptions.  Nothing  can  be  more 
i\idiciou8  or  appropriate  than  the 
sculpture  in  the  metopes  and  pedi- 
ment  of  the  Parthenon.   Ornament 

\  Viere  not  only  creates  a  variety  on 
the  surface  of  the  work,  but  re- 
lates, by  the  aid  of  the  sculptor,  a 
\nat(H7  intimately  connected  with 


the  religious  and  moral  destination 
of  the  edifice  to  which  it  is  applied. 

Decorative  etyle  of  Gothic  Architec- 
ture :  first  introduced  in  the  reign 
of  Edward  I.,  it  was  matured  in 
England,  and  prevailed  during  the 
greater  part  of  the  14th  centur}'. 
Its  distinguishing  features,  says  Dr. 
Whewell,  are  characterized  by  its 
window-tracery,  geometrical  in  the 
early  instances,  flowing  in  the 
later;  but  also,  and  perhaps  bet- 
ter, by  its  triangular  canopies, 
crocketed  and  fiuiided ;  its  niched 
buttresses,  with  triangular  heads  ; 
its  peculiar  mouldings,  no  longer  a 
collection  of  equal  rounds,  with 
hollows  like  the  early  English,  but 
an  assemblage  of  various  members, 
some  broad,  some  narrow,  beauti- 
fully grouped  and  proportioned.  A 
capital  with  crumpled  leaves,  a 
peculiar  base  and  pedestal,  also 
belong  to  this  style. 

Definitions  in  geometry : 

1.  A  point  is  that  which  hath 
no  parts,  or  which  hath  no  magni- 
tude. 

2.  A    line    is    length    without 
'breadth. 

3.  A  superficies  has  length  and 
breadth. 

4.  A  solid  is  a  figure  of  three  di- 
mensions, having  length,  breadth, 
and  thickness.  Hence  surfaces 
are  extremities  of  solids,  and  lines 
the  extremities  of  surfaces,  and 
points  the  extremities  of  lines. 

If  two  lines  will  always  coincide, 
however  applied,  when  any  two 
points  in  the  one  coincide  with 
the  two  points  in  the  other,  the 
two  lines  are  called  straight  lines, 
or  otherwise  right  lines. 

A  curve  continually  changes  its 
direction  between  its  extreme 
points,  or  has  no  part  straight. 

Parallel  lines  are  always  at  the 
same  distance,  and  will  never  meet, 
though  ever  so  far  produced.  Ob- 
lique right  lines  change  their  dis- 


I     *  To  these  the  Sayiour  added  another ;     ««  a  new  commandment  I  give  unto  you,  That 
ye  love  one  another  ;  as  I  have  loved  you,  that  ye  also  love  one  another,"  {John  xiii.  34.) 

139 


DEF 


DEFINITIONS  IN*  GEOMETRY. 


DEF 


tancei  and  would  meet,  if  pro- 
duced. 

One  line  is  perpendicular  to  an- 
other when  it  inclines  no  more  to 
one  side  than  another. 

A  straight  line  is  a  tangent  to  a 
circle  when  it  touches  the  circle 
without  cutting,  when  both  are 
produced. 

An  angle  is  the  inclination  of 
two  lines  towards  one  another  in 
the  same  plane,  meeting  in  a  point. 

Angles  are  either  right,  acute, 
or  oblique. 

A  right  angle  is  that  which  is 
made  by  one  line  perpendicular  to 
another,  or  when  the  angles  on 
each  side  are  equal. 

An  acute  angle  is  less  than  a 
right  angle. 

An  obtuse  angle  is  greater  than 
a  right  angle. 

A  plane  is  a  surface  with  which 
a  straight  Une  will  every  where 
coincide;  and  is  otherwise  called 
a  straight  surface. 

Plane  figures,  bounded  by  right 
lines,  have  names  according  to  the 
number  of  their  sides,  or  of  their 
angles,  for  they  have  as  manysidSS 
as  angles:  the  least  number  is 
three. 

An  equilateral  triangle  is  that 
whose  three  sides  are  equaL 

An  isosceles  triangle  has  only 
two  sides  equal. 

A  scalene  triangle  has  all  sides 
unequal. 

A  right-angled  triangle  has  only 
one  right  angle. 

Other  triangles  are  oblique- 
angled,  and  are  either  obtuse  or 
acute. 

An  acute-angled  triangle  has  all 
its  angles  acute. 

An  obtuse-angled  trianj^e  has 
one  obtuse  angle. 

A  figure  of  four  sides,  or  angles, 
is  called  a  quadrilateral,  or  quad- 
rangle. 

A  parallelogram  is  a  quadrilate 
ral,  which  has  both  pairs  of  its 
opposite  sides  parallel,  and  takes 
the  following  particular  names : 

140 


A  rectangle  is  a  parallelog^in, 
having  all  its  angles  right  ones. 

A  square  is  an  equilateral  rect- 
angle, having  all  its  sides  equal, 
and  all  its  angles  right  angles. 

A  rhombus  is  an  equilateral 
parallelogram  whose  angles  are 
oblique 

A  rhomboid  is  an  oblique-angled 
parallelogram,  and  its  opposite  sides 
only  are  equal. 

A  trapezium  is  a  quadrilateral, 
which  has  neither  pair  of  its  aides 
parallel. 

A  trapezoid  hath  only  one  of  its 
sides  parallel. 

Plane  figures,  having  more  than 
four  sides,  are  in  general  called 
polygons,  and  receive  other  parti- 
cular names  according  to  the  num- 
ber of  their  sides  or  angles. 

A  pentagon  is  a  polygon  of  five 
sides,  a  hexagon  of  six  sides,  a  hep- 
tagon seven,  an  octagon  eight,  an 
enneagon  nine,  a  decagon  ten,  an 
undecagon  eleven,  and  a  dodecagon 
twelve  sides. 

A  regular  polygon  has  aU  its 
sides  and  its  angles  equal ;  and  if 
they  are  not  equal,  the  polygon  is 
irregular. 

An  equilateral  triangle  is  also  a 
regular  figure  of  three  sides,  and 
a  square  is  one  of  four ;  the  former 
being  called  a  trigon,  and  the  latter 
a  tetragon. 

A  circle  is  a  plane  figure, 
bounded  by  a  curve  line,  called 
the  circumference,  which  is  every 
where  equidistant,  from  a  certain 
point  within,  Called  its  centre. 

The  radius  of  a  circle  is  a  right 
Une  drawn  from  the  centre  to  the 
circumference. 

A  diameter  of  a  circle  is  a  right 
line  drawn  through  the  centre, 
terminating  on  both  sides  of  the 
circumference. 

An  arc  of  a  circle  is  any  part  of 
the  circumference. 

A  chord  is  a  right  line  joining 
the  extremities  of  an  arc. 

A  segment  is  any  part  of  a  circle 
bounded  by  an  arc  and  its  chord. 


DEF 


DEFINITIONS  IN  GEOMETRY. 


DEF 


A  semicircle  is  Ixalf  a  drdei  or 
a  segment  cut  off  by  tlie  diameter. 
A  sector  is  any  part  of  a  circle 
bounded  by  an  arc,  and  two  radii 
drawn  to  its  extrenoities. 

A  quadrant,  or  quarter  of  a  cir- 
cle, is  a  sector  having  a  quarter 
part  of  the  circumference  for  its  arc, 
and  the  two  radii  perpendicular  to 
each  other. 

The  height  or  altitude  of  any 
figure  is  a  perpendicular  let  faU 
from  an  angle  or  its  vertex  to  the 
opposite  side,  called  the  base. 

The  measure  of  any  right-lined 
angle  is  an  arc  of  any  circle  con- 
tained between  the<two  lines  which 
form  the  angle,  the  angular  point 
being  the  centre. 

Asohd  is  said  to  be  cut  by  a 
plane  when  it  is  divided  iuto  two 
parts,  of  which  the  common  sur- 
face of  separation  is  a  plane,  and 
this  plane  is  called  a  section. 
Dejinitums  qf  solids  : 

A  prism  is  a  solid,  the  ends  of 
which  are  similar  and  equal  paral- 
lei  planes  and  the  sides  parallelo- 
grams. 

If  the  ends  of  the  prism  are  per- 
pendicular to  the  sides,  the  prism 
is  called  a  right  prism. 

If  the  ends  of  the  prism  are 
oblique  to  the  sides,  the  prism  is 
called  an  oblique  prism. 

If  the  ends  and  sides  are  equal 
squares,  the  prism  is  called  a  cube. 
If  the  base  or  ends  are  paral- 
lelograms, the   solid  is   called  a 
paraUelopiped. 

If  the  bases  and^  sides  are  rect- 
angles, the  prism  is  called  a  rect- 
angular prism. 

If  the  ends  Bxe  circles,  the  prism 
is  called  a  cylinder. 

If  the  ends  or  bases  are  ellipses, 
the  prism  is  called  a  cylindroid. 

A  solid,  standing  upon  any  phme 
figure  for  its  base,  the  sides  of 
which  are  plane  triangles,  meeting 
in  one  point,  is  called  a  pyramid. 

The  solid  is  denominated  from 
its  base,  as  a  triangular  pyramid  is 
one   upon    a    triangular  base,   a 

141 


square  pyramid  one  upon  a  square 
base,  &c. 

If  the  base  is  a  circle  or  an  ellip- 
sis, then  the  pyramid  is  called  a 
cone. 

If  a  solid  be  terminated  by  two 
dissimilar  parallel  planes  as  ends, 
and  the  remaining  surfaces  joining 
the  ends  be  also  planes,  the  solid 
is  called  a  prismoid. 

If  a  part  of  a  pyramid  next  to 
the  vertex  be  cut  off  by  a  plane 
parallel  to  the  base,  the  portion  of 
the  pyramid  contained  between  the 
cutting  plane  and  the  base  is  called 
the  frustrum  of  a  pyramid. 

A  solid,  the  base  of  which  is  a 
rectangle,  the  four  sides  joining  the 
base  plane  surfaces,  and  two  oppo- 
site ones  meeting  in  a  line  parallel 
to  the  base,  is  called  a  cuneus  or 
wedge. 

A  solid  terminated  by  a  surface 
which  is  every  where  equally  dis- 
tant from  a  certain  point  vrithin 
it  is  called  a  sphere  or  globe. 

If  a  sphere  be  cut  by  any  two 
planes,  the  portion  contained  be- 
tween the  planes  is  called  a  zone, 
and  each  of  the  parts  contained  by 
a  plane  and  the  curved  surface  is 
called  a  segment. 

If  a  semi-ellipsis,  having  an  axis 
for  its  diameter,  be  revolved  round 
this  axis  until  it  come  to  the  place 
whence  the  motion  began,  the  solid 
formed  by  the  circumvolution  is 
called  a  spheroid. 

If  the  spheroid  be  generated 
round  the  greater  axis,  the  solid  is 
called  a  prolate  spheroid. 

If  the  solid  be  generated  round 
the  lesser  axis,  the  solid  is  called 
an  oblate  spheroid. 

A  soUd  of  any  of  the  above 
structures,  hollow  vrithin,  so  as  to 
contain  a  soUd  of  the  same  struc- 
ture, is  called  a  hollow  solid 
Defkiffratort  an  instrument  for  pro- 
ducing intense  light  and  heat 
Diction,  a  term  applied  to  the  dis- 
tance by  which  a  curve  departs 
from  another  curve,  or  from  a 
straight  line 


DEF 


DESCRIPTIVE  GEOMETRY. 


DES 


Deflection,  the  deviation  of  a  ship 
from  its  course 

Degree  J  the  360th  part  of  the  circum- 
ference of  a  circle ;  60  geographical 
miles 

Degree,  consisting  of  three  figures  of 
three  places,  comprehending  units, 
tens,  and  hundreds 

DeUguia,  according  to  YitruTins,  gut- 
ters, or  drains 

Delivery  tfohe,  the  upper  yalve  in 
the  air-pump,  or  that  through 
which  the  water  is  lifted  into  the 
hot  well ;  also  used  when  speaking 
of  any  sort  of  pump 

Delphica,  a  tahle  made  of  marhle  or 
bronze,  and  resembling  a  tripod 

Dehtbrum,  a  font  or  baptismal  basin 

Debibrum,  in  antiquity,  a  church, 
chapel,  temple,  or  consecrated 
place 

Delubrum,  that  part  of  a  Roman 
temple  in  which  the  altar  or  statue 
of  the  deity  was  erected 

Dememe,  lands  belonging  to  the  lord 
of  a  manor,  and  which  are  conti- 
guous to  the  manor-house 

Demi^elievo,  in  sculpture,  half-raised 
figures  from  the  plane,  as  if  cut  in 
two,  and  only  half  fixed  to  the  plane 

Demi'tint  is  that  shade  seen  when 
the  sun  shines  on  a  house,  or  any 
other  object,  making  an  angle  of 
nearly  45*^  on  the  ground  plane,  or 
when  it  shines  more  on  the  front 
than  on  the  end. 

Dendrometer,  an  instrument  for  the 
measuring  of  trees 

Denticuhu,  a  member  in  the  Ionic 
and  Corinthian  entablatures,  occur- 
ing  between  the  zophorus  and 
corona,  and  properly  speaking,  a 
part  of  the  latter:  so  called  be- 
cause it  represents  denticuli,  or 
small  teeth,  placed  at  equal  inter- 
vals apart 

Dentils,  ornaments  resembling  teeth, 
used  in  the  bed-mouldings  of  Ionic, 
Corinthian,  and  Composite  cornices 

Departure,  in  navigation,  is  the  east- 
ing or  westing  of  a  ship  with  re- 
spect to  the  meridian  from  which 
it  departed  or  sailed ;  or  it  is  the 
difference  of  longitude  between  the 

142 


present  meridian  and  where  the  last 
reckoning  was  made 

Depression  of  the  pole,  in  navigation  : 
so  many  degrees  as  you  sa^  from 
the  pole  towards  the  equator,  so 
many  you  are  said  to  depress  the 
pole,  because  it  becomes  so  much 
lower  in  the  horizon 

Derrick,  a  Cornish  word  for  a  miner 

Derrick,  in  navigation,  a  tackle  used 
at  the  outer  quarters  of  the  mizen- 
yard;  it  also  signifies  a  prop  or 
support  to  sheers,  &c. 

Derrick,  Sheers  and  Gyn  have  one 
object  in  common, — to  find  a  point 
or  fulcrum  in  space  to  which  the 
pulley,  in  the  shape  of  block  and 
tackle,  is  to  be  supplied ;  and  this 
is  effected  by  the  above,  on  one, 
two,  and  three  legs,  respectiTely. 
In  the  derrick  and  sheers,  stability 
is  given  by  guys ;  in  the  gyn,  they 
are  unnecessary.  Wherever  these 
guys  are  used,  great  attention  must 
be  paid  to  their  being  well  fixed,  or 
being  (when  requisite)  duly  eased. 
off:  when  accidents  occur  from 
neglect  in  this  respect,  they  are 
generally  very  severe. 

Describent,  in  geometry,  is  the  line  or 
surface  from  the  motion  of  which 
a  surface  or  body  is  supposed  to 
be  generated  or  described 

Descr^tive  geometry:  the  applica- 
tion of  geometrical  rules  to  the 
representation  of  the  figures  and 
the  various  relations  of  the  forms 
of  bodies,  in  accordance  to  forms 
applicable  to  civil,  military,  and 
naval  architecture,  civil  and  me- 
chanical engineering,  and  the  other 
arts  that  require  more  correct  aden- 
tific  representations  than  have  hi- 
therto been  afforded  to  the  student 

Desiccation,  the  chemical  operation  of 
drying  bodies,  sometimes  effected 
by  drying  in  the  air,  sometimes  in 
warm  chambers,  by  the  air-pump, 
&c. 

Design,  a  term  in  the  fine  arts,  is  em- 
ployed first  to  signify  the  art  of 
drawing  or  representing  in  lines 
the  form  of  any  object;  next  it  ex- 
presses that  combination  of  inven- 


DES 


DIAPER. 


DIA 


tion  and  purpose  -which  enables  the 
artist  to  compose  a  picture  or  a 
group,  without  reference  to  the 
material  in  which  it  is  executed 

Destma,  according  to  Vitruvius,  a 
column  or  pillar  to  support  an  edi- 
fice 

Devicef  an  emblem  or  ensign  for- 
merly borne  on  shields  or  em- 
broidered upon  banners  as  a  cogni- 
zance ;  contemi>orary,  in  the  history 
of  heraldry,  with  coat  annour  it- 
self 

Detnce,  in  heraldry,  painting,  &c.,  any 
emblem  used  to  represent  a  certain 
femily,  person,  action,  or  quality, 
with  a  suitable  motto,  apptied  m  a 
figurative  sense 

Dexter,  in  heraldry,  an  appellation 
given  to  whatever  belongs  to  the 
right  side  of  a  shield  or  coat  of 
arms,  as  the  bend  dexter,  dexter 
point,  &c. 

Diagonal,  8  line  drawn  from  angle  to 

angle 
Diagonal  rib^    a  projecting  band  of 
stone    or   timber  passing  diagon- 
ally from  one  angle  of  a  vaulted 
ceiling   across  the  centre  to  the 
opposite  anfi^le 
Diagonal  scale.     Equidistant  parallel 
lines   cut    all   lines  drawn  across 
them  into  equal  parts;  consequently 
a  set  of  equidistant  parallels  laid 
down  upon  a  ruler,  with  oblique 
lines  of  various  lengths  drawn  across 
them,  give  with  the  compasses  the 
means   of  immediately  taking  oflf 
various  proportions  of  those  lines. 
Diagram,  a  delineation  of  geometrical 
figures ;  a  mathematical  illustration 
Dial,  an  instrument  for  the  measuring 
of  time  ;  not  mentioned  in  Scrip- 
ture before  the  reign  of  Ahaz,  a.m. 
3262.    It  is  not  clearly  ascertained, 
even  after  this  time,  how  the  Jews 
divided  the  time  by  hours.    The 
word  hour  occurs  first  in  Tobit, 
which  may  confirm  the  opinion  that 
the  invention  of  dials  came  from 
beyond  the  Euphrates. 
Dialling.     In  ^  ^9l%,  the  gnomon 
represents  the  axis  of  the  earth ; 
hence  its  angle' with  the  horizon  is 

143 


the  latitude  of  the  place,  and  it 
lies  in  the  plane  of  the  meridian. 
There  are  a  great  variety  of  dials, 
according  to  whether  they  are  hori^ 
zontal,  oblique,  or  verticid,  and  also 
depending  on  their  aspect  with  re- 
ference to  the  sun,  &c. 

Diamicton,  according  to  Pliny,  a  term 
used  by  the  Roman  builders  to  de- 
signate a  particular  manner  of  con- 
structing walls,  the  exterior  of 
masonry,  and  the  interior  of  rub- 
ble 

Diamond,  a  genus  of  precious  stones 
of  a  fine  pellucid  substance  of  great 
hardness,  and  never  debased  by 
any  admixture  of  earthy  or  other 
coarse  matter.  When  pure,  it  is 
perfectly  colourless.  It  is  the  most 
valuable  of  all  gems,  and  is  found 
only  in  the  East  Indies  and  the 
Brazils.  It  is  constituted  solely  of 
carbon  in  its  densest  form. 

Diamond,  glaziers*,  the  pencil  dia- 
mond, used  in  cutting  glass,  is  a 
small  fractured  piece  of  diamond 

Diaper  ornament,  of  flowers,  apphed 
to  a  plain  surface,  either  carved 
or  painted :  if  carved,  the  flowers 
are  entirely  sunk  into  the  work 
below  the  general  surface;  they 
are  usually  square,  and  placed  close 
to  each  other,  and  are  various  in 
their  pattern  and  design:  it  was  first 
introduced  in  the  Early  EngUsh 
style  in  some  of  the  principal  Gothic 
structures  in  England 

Diaper,  a  panel  or  flat  recessed  sur- 
face covered  with  carving  or  other 
veroughtwork  in  lowreli^;  a  kind 
of  linen  cloth,  wrought  with  fig^es 
in  the  process  of  weaving 

Diastyle,  an  arrangement  of  columns 
in  Grecian  and  Roman  architecture, 
in  which  the  intercolumniation  or 
space  between  them  is  equal  to 
three  or  four  diameters  of  the 
shaft 

Diathyra,  the  vestibule  before  the 
doors  of  a  Greek  house,  correspond- 
ing with  the  prothyra  of  the  Ro- 
mans 

Diatom,  the  angle  stones  of  a  vrall, 
wrought  on  two  faces,  and  which. 


Afc 


DIA 


DILAPIDATIONS. 


DII 


stretching  beyond  the  stones  above 
and  below  them,  form  a  good 
band  or  tie  to  the  work 

Diatonif  according  to  Vitruyius,  the 
girders  or  band-stones  formerly  em- 
ployed in  constructing  walls ;  cor- 
ner stones 

Diatretumt  an  enchased  or  curiously 
engraved  vase  or  drinldng-cup 

Diauhnt  a  race-course,  the  circuit  of 
which  was  two  stadia,  or  1200  feet ; 
whence  it  was  used  to  signify  a 
measure  of  two  stadia 

Dicrotum^  a  boat  with  two  obts 

Die^  the  cube  or  dado  of  a  pedestal 

Die^  or  Dye^  a  naked  square  cube : 
thus  the  body  of  a  pedestal,  or 
that  part  between  its  base  and 
its  cap,  is  called  the  die  of  the  pe- 
destal 

DieSf  two  pieces  of  hardened  steel, 
which,  when  placed  together,  form 
a  female  screw  (or  a  screw  in  a 
nut)  which  has  cutting  edges,  used 
for  making  a  screw  on  a  bolt 

Die-sinJeing :  in  the  preparation  of 
coined  money  and  of  medals,  the 
most  important  feature  is  the  en- 
graving of  the  die  which  is  to  form 
the  stamp.  The  piece  of  steel  is 
prepared  with  care,  and  brought 
to  a  soft  state  when  about  to  be 
submitted  to  the  hands  of  the  en- 
graver. By  the  aid  of  small,  fine, 
hardened  steel  tools,  the  engraver 
cuts  away  the  steel  until  he  has 
produced,  in  cavity  or  intaglio,  an 
exact  reverse  of  the  design  for  the 
medal  or  coin. 

Dieu  et  mon  droit —  *  God  and  my 
right,' — in  heraldry,  the  motto  of 
the  royal  arms  of  England,  first 
assumed  by  Richard  I. 

Differential  thermometer.  This  in- 
strument was  invented  by  the  same 
gentleman  who  contrived  the  pho- 
tometer and  aetherioscope,  and 
was  used  by  him  in  his  investi- 
gations  on  heat.  Its  principal  use 
to  the  meteorologist  is  to  make 
experiments  on  the  light  and  heat 
of  the  moon,  &c.,  by  concentrating 
its  rays  by  a  lens  upon  the  sentient 
ball.    This  can  only  be  done  when 


the  moon  is  on  the  meridian.  Ii 
is  peculiarly  adapted  for  measurini 
the  effect  of  radiation. 

Digester^  a  boiler  invented  by  Papic 
for  raising  water  to  a  higher  tem- 
perature than  the  common  boiling 
point,  212°:  this  is  effected  b; 
forming  a  vessel  somewhat  resem- 
bling a  kitchen  pot ;  the  mouth  is 
formed  into  a  fiat  ring,  so  that  a 
cover  may  be  screwed  tightly  on  ; 
this  cover  is  fumishe^with  a  safety- 
valve,  loaded  to  the  required  pres- 
sure 

Digits  a  finger ;  a  term  employed  to 
signify  any  symbol  of  number  from 
0  to  9 :  thus  ten  (10)  is  a  number 
of  two  digits 

Digits  a  measure  of  length,  containing 
three-fourths  of  an  inch 

Diglgphf  in  architecture,  an  imperfect 
triglyph,  with  only  two  channels 
instead  of  three 

Dilapidation,  decay  for  want  of  repair ; 
not  unfrequently  a  point  of  dispute 
between  a  party  in  possession  of  a 
house  and  another  party  having  an 
interest  therein.    Where  there  is  a 
right  to  use  lands  or  houses,  ques- 
tions will  arise  as  to  the  manner  in 
which  they  ought  to  be  used,  and 
by  whom    dilapidations,  whether 
caused  by  accident  or  decay,  ought 
to  be  supplied.    The  rights  of  par- 
ties  with  respect  to  immoveable 
property  so  closely  border  on  each 
other,  and  the  line  of  demarcation  I 
between  them  is  so  indistinct,  that  I 
one  man,  in  the  fancied  exercise  of 
his  right,  is  continually  liable  to 
encroach  upon  or    disregard  the 
right  of  another.  No  person,  how- 
ever  absolute  his  property  in  land, 
can  put  it  to  any  use  he  pleases : 
his  right  to  use  is  restrained  by  the 
rights  of   his  neighbour;  he    is 
bound  to  take  care  that  his  manner 
of  using  does  not  interfere  with 
the  inoffensive  and  profitable  occu- 
pation  by  his  neighbour  of  his  land. 
(See  the  second  edition,  just  pub- 
lished, of  Mr.  Gibbons's  elaborate 
work  on  the  *  Law  of  Dilapidations 
and  Nuisances.') 


144 


END  OP  PART  I. 


DIL 


DISTEMPER  IN  PAINTING. 


DIS 


DUeitanie  (Italian) ,  an  ardent  admirer 
of  the  fine  arts.  The  Dilettanti 
Society,  consisting  of  many  dis- 
tinguished  noblemen  and  gentle- 
men,  has  done  much  to  rescue  the 
noble  monuments  of  Grecian  art 
from  otherwise  inevitable  ruin 

DiUeuinff,  a  Cornish  word  for  a  method 
of  washing  or  finishing  the  dress- 
ing of  tin  in  very  fine  hair  sieves 

Dibtvial  /brmation,  the  superficial 
deposits  of  gravel,  clay,  sand,  &c., 
which  lie  far  from  their  original 
sites  on  hillsy  and  in  other  situ- 
ations, to  which  no  forces  of  water 
now  in  action  could  transport  them 

Dimenrion,  a  term  used  m  the  same 
sense  as  degree 

Bimmiawn,  a  term  expressing  the 
gradual  decrease  of  thickness  in 
the  upjier  part  of  a  column 

Dimtautton  of  cohanns.  The  shafts 
of  colunms  are  diminished  in  dia- 
meter as  they  rise,  sometimes  from 
the  foot  itself  of  the  shaft,  some- 
times  from  one-quarter,  and  some- 
times from  one-third  of  its  height. 
The  diminution  at  top  is  seldom 
less  than  one-eighth  or  more  than 
one-sixth  of  the  inferior  diameter 
of  the  column. 

Dkptase,  or  emerald  copper,  a  crys- 
tallized sihcate  of  copper,  the  pri- 
mary form  of  which  is  a  rhomboid. 
Its  colour  varies  from  emerald  to 
blacldsh  green:   it  is  translucent 

and  brittle 

Dioptra,  a  geometrical  instrument 
employed  in  measuring  the  altitude 
of  distant  objects,  andfor  takmgthe 
levels  of  a  source  of  water  intended 
to  be  conveyed  to  a  distance  by 
means  of  an  aqueduct 

Diorama,  a  mode  of  scenic  exhibi- 
tion  invented  by  two  French  artists, 
Daguerre  and  Bouton 

D^M  mining,  the  greatest  mchnation 
of  a  stratum  to  the  horizon 

DiPaUto  is  a  ligl»*  yellow  ochre, 
affording  tints  rather  purer  m  co- 
lour than  the  atone  ochre,  but  less 
BO  than  Naples  yeUow.  Many 
pleasing  varieties  of  ochreous  co- 
lours  me    produced   by   burning 


and  compounding  with  lighter, 
brighter,  and  darker  colours,  but 
often  very  iigudiciously  and  ad- 
versely to  that  simple  economy  of 
the  palette  which  is  favourable  to 
the  certainty  of  operation,  effect, 
and  durabiUty. 

D^Unthiua,  according  to  Yitruvins, 
two  bricks  thick 

Dipping-needle,  in  navigation,  a  mag- 
netic needle,  so  hung  that  one  end 
dips,  or  inclines  to  the  horizon,  and 
the  other  is  proportionally  elevated, 
forming  an  angle  equal  to  the  dip- 
ping of  the  needle  at  the  place 
where  the  experiment  is  made 

Dipteral,  having  a  double  range  of 
columns  aU  round :  a  dipteral  tem- 
ple usually  had  eight  in  the  front 
row  of  the  end  porticoes,  and  fifteen 
at  the  sides,  the  columns  at  the 
angles  being  included  in  both 

D^teron,  in  ancient  architecture,  a 
temple  surrounded  with  a  double 
row  of  columns  which  form  porti- 
coes, called  wings  or  aisles 

D^teros,  in  Greek  architecture,  a 
temple  vrith  a  double  row  of  co- 
lumns on  each  of  the  four  sides 

Direct-action  engine,  an  engine  having 
the  rotatory  motion  communicated 
to  a  crank  placed  directly  over  the 
cylinder,  so  as  to  save  height,  and 
lessen  the  weight  of  the  engine: 
the  term  applies  more  particularly 
to  marine  engines 

Discharging  arch,  an  arch  formed  in 
the  substance  of  a  wall,  to  relieve 
the  part  which  is  below  it  from  the 
superincumbent  weight  i  it  is  fre- 
quently used  over  lintels  and  flat- 
headed  openings 

Discard,  a  term  appfied  to  painting 
when  there  is  a  disagreement  of 
the  parts  or  the  colouring ;  when 
the  objects  appear  foreign  to  each 
other,  and  have  an  unpleasing  and 
unnatural  effect 

Ditembogue,  to  pour  out  at  the  mouth 
of  a  river 

Diatengier,  in  painting,  the  working- 
up  of  colours  with  something  else 
besides  mere  water  or  oiL  U  the 
colours  be  prepared  with  the  first, 


145 


DIS 


DOCKS. 


DOC 


it  is  called  limning;  and  with  the 
last,  painting  in  oil 

Distemper  is  a  preparation  of  colours 
without  oil,  only  mixed  with  size, 
whites  of  eggs,  or  any  such  proper 
glutinous  or  unctuous  substance : 
with  this  kind  of  colour  all  the  an- 
cient pictures,  before  the  year  14 10, 
were  painted,  as  also  are  the  cele- 
brated cartoons  of  Raphael 

IHtriglypht  an  interval  between  two 
columns,  admitting  two  triglyphs 
in  the  entablature;  used  in  the 
Doric  order 

Dividicubimf  in  Rome,  a  tower  on  an 
aqueduct,  containing  a  large  reser- 
voir 

Diving  bell,  a  machine  contrived  for 
safely  lowering  a  man  to  any  rea- 
sonable depth  under  water,  so  that 
he  may  remain  there  for  a  consi- 
derable time 

Dnntion  of  an  Order,  The  general 
division  of  an  order  being  into  two 
ports,  namely,  the  column  and  en- 
tablature, the  column  is  subdivided 
into  three  unequal  parts,  viz.  the 
base,  the  shaft,  and  the  capital. 
The  entablature  consists  also  of 
three  unequal  parts,  which  are,  the 
architrave,  the  frieze,  and  the  cor- 
nice.  Each  of  these  divisions  con- 
sists of  several  smaller  parts,  which 
by  their  variety  and  peculiarity  dis- 
tinguish the  orders  from  each  other. 

Dock,  a  place  artificially  formed  for 
the  reception  of  ships,  the  entrance 
of  which  is  generally  closed  by 
gates.  There  are  two  kinds  of 
docks, — dry  docks  and  wet  docks : 
the  former  are  used  for  receiving 
ships  for  repair,  the  latter  for  the 
purpose  of  keeping  vessels  afloat. 

Docks  are  enclos^  artificial  recepta- 
cles for  shipping,  and  are  usually 
formed  by  excavation  of  the  soil, 
and  constructed  walls  of  masonry, 
vrith  inlets  and  gates  for  admitting 
the  passage  of  vessels.  Docks  are 
usuiQly  distinguished  as  wet  docks 
or  basins,  and  dry  or  graving  docks. 
The  former  of  these  are  already 
described  under  the  headBonn;  the 
latter  maybe  described  as  follows : 

146 


Graving  docks,  in  which  repairs 
of  vessels  are  effected,  are    con- 
structed of  various  dimensions,  ac- 
cording to  the  class  of  vessel  for 
which  provision  is  intended.     Se- 
veral splendid  works  of  this  kind 
have,  within  the  last  few   years, 
been  executed  in  the  English  dock- 
yards.   One  of  these, — ^the  Eastern 
Dock  in  Her  Majesty's  Dockyard 
at  Woolwich, — is  282  feet  in  ex- 
treme length,  81  feet  in  width  on 
the  ground  level,  and  39  feet  in 
the  bed.     The  depth    from    the 
ground  level  to  the  bed  is  27  feet. 
The  inclined  sides  and  curved  end 
of  the  masonry  are  formed  into  a 
series  of  steps  or  altars,  by  which 
access  is  readily  obtained  to   all 
parts  of  the  dock,  and  fixing-places 
obtained  for  the  struts  with  which 
the  sides  of  the  vessel  under  repair 
are  maintained  in  an  upright  posi- 
tion, when  the  water  is  discharged 
from  the  dock.    The  river- waU  of 
this  structure  was  originally  con- 
structed of  concrete  block-facings 
vrith  rough  concrete  backing,  ac- 
cording to  a  plan  introduced  into 
this  country  by  Mr.  Ranger ;  but 
these  were  abandoned,  and  granite 
facings  substituted,  the  entire  mass 
of  the  wall  being  supported  on 
timber-piling.    The  whole  of  the 
piers,  apron,  and  coffer-dam  walls 
were  executed  by  tide-work,  in  the 
following  manner:  a  small  space 
vras    surrounded   by  sheet-piling, 
which  was  carried  up  from  6  to  8 
feet  above  the  level  of  low  water : 
into  the  enclosure  thus  formed  a 
pipe   from   two    18-inch  pumps, 
worked  by  a  steam  engine,  was 
led,  and  the  pumps  set  to  work  as 
soon  as  the  tide  fell  below  the 
sheet-piling.    The  subsequent  ex- 
cavation for  the  dock  reached  a 
bed  of  chalk,  which  was  found  to 
be  sufiidently  firm  to  dispense  with 
the  inverted  arch  of  masonry  usu- 
ally constructed  beneath  the  bed  of 
these  dockSi  and  the  floor  was  con- 
sequently 'Constructed  of  a  hori- 
zontal paving  of  blocks  of  granite 


DOC 


DOCKS,  GRAVING. 


DOC 


2  feet  in  thickness,  each  stone 
being  joggled  to  the  a4iaoent  stones 
with  dove-tail  joggles  of  Valentia 
slate  bedded  in  cement.  The  river 
water  is  admitted  into  the  dock 
throagh  a  caWert  5  feet  high  and 

3  feet  wide,  passing  throagh  each 
pier,  and  which  culverts  are  worked 
by  sluiees  of  cast  iron.  The  front 
of  the  dock  is  closed  with  a  caisson 
formed  of  plate  iron,  fixed  with 
rivets  to  ribs  of  angle  iron ;  the 
form  of  the  caisson  being  similar 
to  that  of  a  vessel,  namely,  with  a 
continuous  keel  along  the  bottom 
and  up  each  end,  and  a  swelling 
outline  tapering  towards  the  end 
keels,  and  reduced  to  a  width  nearly 
parallel  in  the  deck-level.  This 
continuous  keel,  which  is  of  oak, 
and  formed  in  two  pieces,  fits  into 
a  recess  in  the  masonry  at  the  en- 
trance of  the  dock,  and  the  admis- 
sion of  water  into  it  is  regulated 
by  sluices  and  pumps. 

Prom   the  description  given  of 
graving  docks,  it  will  be  under- 
stood that  their  action  andeflSdency 
depend  upon  the  command  of  an 
adequate  depth  of  water,   and  a 
sufficient  rise  and  fall  of  tide  to 
leave  the  vessel  dry  or  to  float  her, 
as  occasion  requires.     The  use  of 
these  docks  also  compels  the  re- 
tention  of  the  vessel  during  the 
action  of  the  tide,  and  thus  involves- 
a  considerable  lapse  of  time,  which 
sometimes  cannot  be  afforded  for 
trifling  repairs  or  examination  of  a 
vessel  in  active  service. 

For  situations  in  which  no  tide 
exists,  a  diflTerent  arrangement  be- 
comes necessary,  and  a  construc- 
tion called  a  'slip'  is  commonly 
substituted    for    a  gracing  dock. 
The  slip  which  has  been  the  most 
extensively  used  is  that  known  as 
*  Morton's  slip,'    and  which  was 
secured  by  a  patent  dated  March 
23,  1819,  granted  to  T.  Morton, 
for  a  method  of  dragging  ships  out 
of  water  for  repairs,  &c.      This 
8%  consists  of  an  inclined  plane, 
formed  of  timber  framing  laid  upon 


suitable  foundations  of  masonry,  or 
cut  in  the  surface  of  the  rock. 
Upon  this  framing  longitudinal 
metal  racks  are  fixed,  and  a  move- 
able carriage,  upon  which  the  ves- 
sel is  received,  (by  running  the 
carriage  to  the  lower  part  of  the 
plane,  beneath  the  water,  and  se- 
curing the  vessel  upon  it,)  is  fitted 
with  cog-wheels,  or  other  suitable 
apparatus  for  working  upon  these 
racks.  The  moving  carriage  con- 
sists of  a  succession  of  sn^  strong 
blocks  or  carriages,  any  number  of 
which  may  be  connected  together, 
according  to  the  length  of  vessel 
to  be  hauled  up.  Each  of  these 
blocks  or  carriages,  which  are  laid 
in  corresponding  pairs  on  each 
side  of  the  central  line  of  the  slip, 
so  as  to  leave  a  continuous  inter- 
mediate space  to  receive  the  keel 
of  the  vessel,  is  fitted  with  rollers, 
upon  which  it  may  be  moved  trans- 
versely ;  and  thus  the  distance  be- 
tween the  two  blocks  of  each  pair, 
or  on  each  side  of  the  centre,  may 
be  adjusted  according  to  the  sec- 
tional form  of  the  ship.  These 
motions  are  ingeniously  effected 
with  the  aid  of  cross  ropes  or  lines 
which  are  fixed  to  the  blacks,  and 
by  which  means  the  entire  action 
of  the  apparatus  is  much  facili- 
tated. The  combined  carriage, 
when  loaded  with  the  vessel,  is 
hftuled  up  the  slip  by  cables  at- 
tached to  a  drum  apparatus,  with 
suitable  gearing  fixed  in  a  building 
at  the  head  or  upper  end  of  the 
slip.  The  power  required  is  of 
course  in  proportion  to  the  weight 
to  be  hauled  up,  and  to  the  rate  of 
inclination  of  the  slip,  and  is  usu- 
ally supplied  by  a  steam  engine. 

This  principle  is  susceptible  of 
being  extended,  so  as  to  provide 
berths  for  several  vessels  with  only 
one  hauling-up  slip  and  machinery. 
For  this  purpose  it  has  been  sug- 
gested to  construct  a  series  of 
frames  arranged  radially  round  a 
centre,  and  capable  of  motion  and 
of  adjustment,  with  one  slip  con- 


147 


DOD 


DOGS  OR  ANDIRONS. 


DOG 


stnicted  in  such  a  direction  aa  to 
correspond  with  a  produced  radius 
of  the  same  circle.  This  arrange- 
ment, which  would  he  similar  to 
that  of  the  polygonal  engine-houses 
now  erected  on  seveial  lines  of 
railway,  offers  great  facilities  for 
extended  operations  in  the  repair 
of  vessels,  but  of  course  requires 
great  space  for  the  construction  of 
the  radial  frames. 

In  order  to  provide  for  cases  in 
which  sufficient  tidal  difference 
cannot  be  had  for  raising  vessels  of 
deep  draughts  on  to  a  dry  dock, 
floating  docks  have  been  introduced 
in  North  America,  and  found  to 
act  satisfactorily.  These  floating 
docks  are  constructed  with  a  buoy- 
ant bed,  or  cradle,  capable  of  sup- 
porting a  vessel  within  the  dock, 
with  its  keel  above  the  surface  of 
the  water.  This  float  or  cradle  is 
made  in  a  box-like  form,  composed 
of  strong  logs,  jointed  firmly,  and 
well  caulked,  so  as  to  make  it 
water-proof.  The  capacity  of  the 
float  must  be  such  that  when  freed 
from  water  by  pumping,  and  loaded 
with  the  vessel,  workmen,  &c.,  it 
shall  sustain  this  load  with  safety. 
The  float  moves  within  a  recess 
of  masonry,  by  which  its  motion 
is  guided  and  secured.  Suitable 
shores,  blocks,  struts,  &c.,  are  used 
in  making  the  vessel  steady  within 
the  float,  which  is  fitted  with  valves 
in  the  lower  part.  The  action  of 
this  floating  dock  is  aa  follows: 
The  cradle  or  float,  being  full  of 
water  (the  valves  being  open),  is 
sunk  so  that  the  vessel  may  be 
brought  over  it,  and  temporarily 
secured  in  position :  the  valves  are 
then  closed,  and  the  pumps  set  to 
work  to  clear  the  water  from  the 
float,  which  rises  in  consequence, 
and  brings  up  the  vessel  to  a  dry 
level.  When  the  ship  is  again  ready 
for  sea,  the  opening  of  the  valves 
admits  the  water,  and  sinks  the 
float,  leaving  the  vessel  free  above 
it  to  pass  out  of  the  dock. 

The  docks  and  basins  of  London 


and  Liverpool  comprise  aoine   of 
the  largest  specimens  of  works  of 
this  kind.  Those  of  the  latter  port 
were  commenced  in  1708,  and  con- 
sist  of  several  docks  of  great  ex- 
tent.    The  first  public  docks  for 
merchant  shipping  in  London  were 
the  West  India  Docks,  opened  in 
1805,  the  great  basin  of  which  is 
420  yards  in  length,  and  230  yards 
in  width.    This  is  connected  with 
the  river  by  another  basin  of  about 
three  acres  in  area.    The  London 
Docks  were  commenced  soon  after 
the  West  India  Docks,  and  opened 
in  the  same  year,  viz.  1805.      The 
principal  basin  of  these  docks  is 
420  yards  in  length,  and  276  yards 
in  width.    The  East  India  Dock 
for  unloading  inwards  is  470  yards 
in  length,  and  173  yards  in  width  ; 
and  that  for  loading  outwards  is 
260  yards  in  length,  and  140  yards 
in  width.     The    St.   Katherine's 
Docks  occupy  an  area  of  24  acres. 

Dodeeagotif  in  geometry,  a  figure  of 
twelve  angles  and  sides 

Dodecahedron,  in  geometry,  one  of 
the  regular  bodies  comprehended 
under  twelve  equal  sides,  each  of 
which  is  a  pentagon 

JDodecastylef  a  bulling  having  twelve 
columns  in  front 

JDogSf  or  andirons,  creepers,  braziers, 
&c.    Long  after  the  general  intro- 
duction of  chimneys,  wood  was  the 
ordinary  fiiel  for  all  sorts  of  apart- 
ments.    Coals  formed  no  part  of 
the  *  liveries,'  but  wood  was  com- 
monly included  in  them.    A  '  era- 
die  for  sea  coal'  is,  however,  fre- 
quently mentioned  as  belonging  to 
the  chief  rooms  in  superior  houses, 
though  the  usual  way  of  warming, 
or  rather  airing,  bed-chambers  was 
with  braziers    or   chafing-dishes. 
Andirons  are  a  larger  and  higher 
sort  of  irons,  made  to  support  the 
wood,  and  have  usually  long  necks 
rising  up  before,  to  prevent  the  I 
wood  from  falling  upon  the  floor. 
Creepers   are   smaller  and  lower 
irons,  with  short  necks,  or  none  at 
all,  which  are  placed  between  the 


148 


DOG 


DOMES. 


DOM 


andirons,  to  keep  tbe  ends  of  the 
wood  and  the  brands  from  the 
hearth,  that  the  fire  may  bum 
more  freely. 

Dog-kewnel,  a  lodgement  for  dogs 
kept  for  the  purpose  of  field  sports : 
it  is  almost  as  inTariable  an  ap- 
pendage to  the  manor-house  as 
it  was  formerly  to  the  baronial 
castle.  Bishop  Percy  observes, 
'*that  a  nobleman  in  the  dark 
ages,  retired  within  his  castle,  had 
neither  books,  nor  newspapers,  nor 
literary  correspondence,  nor  visits, 
nor  cards,  to  fill  up  his  leisure :  his 
only  amusements  were  field  sports ; 
nor  did  the  love  for  these  decline  in 
the  Tudor  period." 

Dog  woody  a  small  underwood,  free 
from  silex :  small  splinters  are  used 
by  watch-makers  for  cleaning  out 
the  pivot-holes  of  watches ;  it  is 
also  used  by  butchers  for  making 

skewers 

Dolomite^  massive  magnesian  lime- 
stone, used  by  the  ancient  sculptors 
in  their  best  works 

Dolphin,  a  technical  term  applied  to 
the  pipe  and  cover  at  a  source  for 
the  supply  of  water 

Dome,  a  term  applied  to  a  covering  of 
the  whole  or  part  of  a  building: 
the  word  dome  is  strictly  applied 
to  the  external  part  of  the  spheri- 
cal or  polygonal  roof,  and  cupola 
to  the  internal  part 

Dome  or  cupola,  a  roof,  the  base  of 
which  is  a  circle,  an  ellipsis,  or  a 
PolyKon,  and  its  vertical  section  a 
curve  line,  concave  towards  the  in- 
terior. Hence  domes  are  called 
circular,  elliptical,  or  polygonal, 
according  to  the  figure  of  the  base. 
The  most  usual  form  for  a  dome 
is  the  spherical,  in  which  case  its 
plan  is  a  circle,  the  section  a  seg- 
ment of  a  circle. 

The  top  of  a  large  dome  is  often 
finished  with  a  lantem,  which  is 
supported  by  the  framing  of  the 

dome. 

The  interior  and  extenor  forms 
of  a  dome  are  not  often  alike,  and 
in  the  space  between,  a  staircase  to 


the  lantern  is  generally  made.  Ac- 
cording to  the  space  left  between 
the  external  and  internal  domes, 
the  framing  must  be  designed. 
Sometimes  the  fivning  may  be 
trussed  with  ties  across  the  open- 
ing; but  often  the  interior  dome 
rises  so  high  that  ties  cannot  be 
inserted. 

Accordingly,  the  construction  of 
domes  may  be  divided  into  two 
cases:  viz.  domes  with  horizontal 
ties,  and  those  not  having  such 
ties. 

Dome,  in  locomotive  engines,  the 
conical  part  of  the  boiler,  forming 
a  steam  chamber,  and  terminating 
the  top  of  the  fire-box  part.  In 
a  locomotive  engine  the  safety- 
valves  are  usually  placed  on  the 
top  of  the  dome  or  the  body  of  the 
boiler 

Dome  cover,  in  locomotive  engines, 
the  brass  or  copper  cover  which 
encloses  the  dome,  to  prevent  the 
radiation  of  heat 

Dome  Cathedral  of  Pisa,  the  first 
model  of  that  Tuscan  style  of  ar- 
chitecture, so  solid,  grave,  and  im- 
posing, neither  Greek  nor  Gothic, 
was  begun  in  the  eleventh  century ; 
and  in  the  thirteenth  was  founded 
the  majestic  church  of  Santa  Maria 
del  Fiori  at  Florence,  of  which  the 
dome  equals  in  size  that  of  St. 
Peter's  at  Rome,  and  was  its  model 

Dome  qfSt.  PauTe  Cathedral  (the)  is 
elliptical,  and  built  of  wood;  it  is 
confined  by  strong  chains,  consist- 
ing of  iron  bars :  that  of  the  Pan- 
theon at  Rome  is  nearly  circular, 
and  its  lower  parts  are  so  much 
thicker  than  its  upper  parts  as  to 
afford  sufficient  resistance  to  their 
pressure;  they  are  supported  by 
walls  of  great  thickness,  and  fur- 
nished with  many  projections  which 
answer  the  purpose  of  abutments 
and  buttresses 

Domes  in  Asia  are  probably  more 
ancient  than  in  Italy.  At  Lanker- 
rood,  at  Dhay-nain,  at  Sin-sin,  five 
or  six  days'  journey  south  of  Tehe- 
ran in  Persia,  towns  are  all  de- 


149 


DOMESTIC  ARCHITECTURE. 


Krted :  there  u-e  about  a  hundred 
large  dwelling-hoiuei  quit«  ejitiie, 
of  a  very  aingulai  conBtmctkin. 
Each  edifice  stands  separate,  and 
ia  constructed  of  seeeraJ  central 
arches  supporting  a  pointed  dome ; 
while  imaller  diiisiooa  project  from 
the  bod;  of  the  boildiiig,  also 
arched,  and  the  whole  finished 
with  the  greatest  neatness,  having 
remaini    (^   stucco-painted   walls 

It  is  probable  that  the  arch  and 
vault  and  dome  were  not  nnltnown 
to  the  nationi  in  the  East,  befoad 
the  Indies,  in  a  eery  remote  tge ; 
but  in  Greece  and  in  Asia  Minor 
there  are  do  traces  of  them  before 
their  introduction  by  the  Romans. 
To  the  Romuis  they  were  familiar 
at  a  very  early  period  of  their  his- 
tory; a  knowledge  of  which  they 
bomiwed  perhaps  &om  the  Etrua- 


cana,  or  from  the  supposed  eitinct 
people  who  possessed  a  dty  on 
the  site  of  Rome  itself,  before  the 

Dmneiiic  Arcfiileehtre  ia  England. 

At  the  tecmiaatian  of  the  Yorii  and 
Lancaster  wars,  the  fbrtiBed  style 
of  architecture  was  gradually  aban- 
doned in  England;  and  as  we  had 
no  other  model  of  domestic  archi- 
tecture than  the  gable  and  the  cot- 
tage, hy  the  duplication  of  this 
simple  form,  in  variaua  positions, 
was  constructed  what  has  been 
coUed  the  Old  EngUsh  Manor- 
honse  style.  If  we  take  a  conuoon 
two-floored  English  gable  and  cot- 
tage, add  to  it  one,  two,  or  three 
cottages  side  by  side,  of  the  same 
size ;  and  in  order  to  gain  rooms 
out  of  the  roof  on  the  sides  of  this 
double  or  triple  cottage,  raise  gable 
ends  either  projecting  from  the 


DOM 


DOMESTIC  BUILDINGS  AND  CASTLES. 


DOO 


ground  to  the  top  of  the  roof,  or 
merely  raised  from  the  eaves-drop ; 
if  we  insert  broad  low  windows, 
divided  by  simple  wooden  or  stone 
ffluUions,  in  these  projecting  gable 
ends,  and  similar  windows  at  the 
ends  of  this  doable  or  triple  cot- 
tage; ornament  the  inclined  sides 
of  the  gable  ends  above  the  eaves- 
drop by  steps  or  small  pinnacles,  or 
bo& ;  then  add  a  parapet,  plain  or 
embattled,  we  have  a  manor-house 
in  the  most  florid  style.  Many 
such  houses  came  afterwards  to  be 
adorned  by  a  centre  of  architec- 
tural decoration,  in  which  Roman, 
Grecian,  and  Gothic  were  strangely 
mixed.  There  is,  however,  a  cer- 
tain degree  of  antique-like  gran- 
deur in  such  houses,  which  pro- 
duces a  very  striking  impression. 
This  step  towards  a  better  style  took 
place  before  the  time  of  Inigo  Jones. 
**  The  mansion  at  South  Elmham 
(represented  on  thejireceding  page), 
when  entire,  formed  a  quadrangle, 
as  usual,  of  which  stables  and 
offices  made  up  a  part.  The  do- 
mestic and  ecclesiastical  styles  are 
singularly  combined  in  this  build- 
ing, though  the  latter  seems  to 
predominate;  and  the  occasional 
discovery  of  old  floor-stones,  of  a 
sepulchral  character,  intimates  that 
the  projecting  porch  led  to  the 
chapel  of  the  dwelling,  not  into 
the  hall;  and  yet  the  ceilings  of 
the  chambers  where  the  two  wings 
and  upper  windows  are  observed, 
on  the  right  hand  of  the  porch,  are 
flat,  divided  into  small  squares  by 
the  girders  above,  and  covered  with 
plastered  mouldings,  in  the  manner 
usually  seen  in  dwellings  of  an 
early  period." 
Domegtic  buildinffg  and  castles.  The 
towns  and  ordinary  houses  of  the 
Normans  were  entirely  built  of 
wood,  and,  for  the  most  part,  are 
80  to  this  day.  Their  castles, 
having  but  one  destination,  that  of 
defence,  aimed  at  nothing  but 
strength  in  their  plan  or  construc- 
tion.     A   site  was   also   selected 


which   was    already   fortified   by 
nature. 

The  plan  of  the  Norman  castles 
was  as  nearly  the  same  as  the  di- 
versity of  ground  would  allow. 
The  principal  feature  was  always 
the  keep,  which  contained  the 
apartments  of  the  lord  of  the  castle, 
and  was  also  meant  to  be  the  last 
refuge  of  the  garrison,  if  the  outer 
works  were  forced.  The  keep  was 
usually  raised  on  an  artificial 
mound,  or  placed  on  the  edg^  of  a 
precipice.  The  walls,  strengthened 
in  every  way  that  art  could  devise, 
were  of  immense  thickness,  and 
composed  of  grouting  poured  in 
between  two  solid  wfdls  of  stone. 
The  facing  consisted  sometimes  of 
irregular  courses,  and  sometimes  of 
small  squared  stones,  alter  the  Ro- 
man numner.  Ashler  was  usually 
introduced  at  the  angles  of  the 
building.  The  windows  were  few, 
and  little  more  than  chinks,  unless 
very  high  up,  or  turned  to  the 
court.  The  door  of  entrance  could 
only  be  reached  by  a  staircase. 

Under  the  keep  were  usually 
vaults,  or  dungeons,  for  the  recep- 
tion of  prisoners. 

The  keep  was  enclosed  in  two 
courts  surrounded  by  walls  flanked 
with  towers.  The  tower  at  the 
entrance  was  called  the  barbican, 
and  served  at  once  for  an  outwork 
andpost  of  observation.  The  whole 
fortress  was  defended  by  a  moat. 

The  remains  of  the  Norman  cas- 
tles which  exist  scarcely  afford  any 
specimens  of  early  Norman  con- 
struction, almost  all  these  castles 
having  been  besieged,  destroyed, 
and  rebuilt,  over  and  over  again. 

The  keep  of  Falaise  is  perhaps 
the  only  castellated  remnant  of 
early  Norman  times. 

The  castle  of  Gizors,  which  was 
built  by  William  Rudfus,  retains 
nothing  of  its  original  construction. 
Domust  a  private  house  occupied  by 
a  single  proprietor  and  his  family 
Doors  {Antique),  The  Greeks  in  the 
temple    of    Minerva    Polias,    at 


151 


WX)                              DOOBS,  ANGLO-NORMAN.                              DOO  j 

Athena,  and  ilso  the  Ramaiu  in 

Doari   (Modem).     There    are     two 

the  temple  of  Vert*  or  the  Sibyl, 

doors,  designs   of  \^gnol«,  which 

■t  TiToU,  nude  the  doors  and  win- 

dow! gmHUet  at  top  than  at  bot- 

tions  a  happT  medium  between  the 

and  all  otiier  designs  of  thia  kind 

are  either  derived  fiom  tbeiD,  or 

the  building.    Tfaoie  of  the  win- 

posseu a  vague  character  whicli 

dow!  in  the  Gredan  temple  have 

renders  thran  unworthy  of  imita- 

a projection,  or  what  is  aometimei 

tion. 

termed  a  knee,  at  their  upper  angle ; 

There  are  breaks  in  the  archi- 

while thoie  of  the  temple  of  Vesta, 

trave,  as  in  those  of  the  temple 

whose   apertures    have  the   same 

of  Minerva  Pohas  i  and  the  ter. 

form,  continue  without  intermp- 

mination   or   lower   extremity     of 

tion,  and  are  surmounted  by  a  cor- 

nice! but  the  cornice  above  the 

of  the  consoles,  which  gives  har- 

door is  separated  from  the  archi- 

mony  to  the  arrangement.    These 

trftie  b7  a  frieze,  while  the  cornice 

consoles  are  alio  placed  against  a 

of  the  windows  joins  the  archi- 

second  architrave,  beyond  which 

ti«»e.     In  the  temple  of  Minerra, 

the  first  projects.    The  design  of 

the  architrave  of  the  windows  rerts 

the  door  of  the  church  of  St.  Lo- 

only  on  a  pUin  socle ;  those  of  the 

renio  is  more  regular. 

temple  of  Ve«tt  test  also  on  a  sode 

JJoonray     {^ngla-NBrnun,).         The 

OTBupport,  the  face  of  which  is  sunk. 

Anglo-Norman  bmlden  bestowed 

much  paiaa   and 

~  .     ..                      evinced  conaider- 

|(i,£                      able  artistic  skill 

ipro*^"                  in  very  elaborately 

^^JHia               portal    entrances 

S^yHBt             to    churches     in 

SSJ^jHEv             their  style  of  «p- 

PKaJftSffla-        chitectuie,   by    a 

■JV»Xr?¥l         1  mfusion  of  oma- 

IJjy^aiJ         me  ital  mouldings  | 

r—         and  of  sculpture. 

\erT    many     ei. 

amples  are  to  be 

met  with  in  great 

II     ' 

variety  in  several 

of  the  counties  of 

Lngland,  particu. 

larly  in  the  coun- 

tes    of    Norfolk 

andSuflblk.   The 

[ 

PlJ 

example      repre- 

sented in  the  an- 

'  id 

^^I^EB 

W 

neied    engraving 

1,  a  beautiful  spe- 

t             J-  cunen  taken  from 

—  !^ 

'V-S 

^                     \          V        .                the  church  of  St.  | 

I                              ui  the  county  of 

Snffolk.                 j 

DOR 


DORIC  ORDER. 


DOS 


Doonoays,  In  the  Gothic,  and  the 
architecture  of  thje  middle  ages, 
doorways  are  striking  and  import- 
ant features,  affording  in  the  cha- 
racter of  the  mouldings  and  orna- 
ments the  style  and  period  of  the 
edifice. 
Doric  Order.  The  Doric  order,  says 
PaUadio,  was  invented  by  the  Do- 
rians  and.  named,  from  them,  being 
a  Grecian  people  which  dwelt  in 
Asia.  If  Doric  columns  are  made 
alone  without  pilasters,  they  ought 
to  be  seven  and  a  half  or  eight 
diameters  high.  The  intercolumns 
are  to  he  little  less  than  three 
diameters  of  the  columns ;  and  this 
manner  of  spacing  the  columns  is 
by  Vitruvius  called  Diastylos. 

The  ancients  employed  the  Doric 
in  temples  dedicated  to  Minenra, 
to  Mars,  and  to  Hercules,  whose 
grave  and  manly  dispositions  suited 
well  with  the  character  of  this  or- 
der. Serho  says  it  is  proper  for 
churches  dedicated  to  Jesus  Christ, 
to  St.  Paul,  St.  Peter,  or  any  other 
saints  remarkable  for  their  forti- 
tude in  exposing  their  lives  and 
suffering  for  the  Christian  faith. 
Le  Clerc  recommends  the  use  of 
it  in  all  kinds  of  military  build- 
ings ;  as  arsenals,  gates  of  fortified 
places,  g^ard-rooms,  and  similar 
structures.  It  may  likewise  be 
employed  in  the  houses  of  gene- 
rals or  other  martial  men, — in 
mausoleums  erected  to  their  me- 
mory, or  in  triumphal  bridges  and 
arches  built  to  cdebrate  their  vic- 
tories. 

Vitruvius  himself  makes  the  Doric 
column  in  porticoes  higher  by  half 
a  diameter  than  in  temples;  and 
most  modem  architects  have,  on 
some  occasions,  followed  his  exam- 
ple.  In  private  houses,  therefore,  it 
may  be  16^,  16i,  or  16f  modules 
high ;  in  interior  decorations,  even 
seventeen  modules,  and  sometimes 
perhaps  atrifle  more;  which  increase 
in  the  height  may  be  added  entirely 
to  the  shaft,  as  in  the  Tuscan  order, 
without  changing  either  the  base 


or  capitaL  The  entablature,  too, 
may  remain  unaltered  in  all  the 
aforesaid  cases ;  for  it  will  be  suffi- 
ciently bold  without  alteration. 

Dwie  Order,  The  height  of  the 
Doric  column,  including  its  capital 
and  base,  is  sixteen  modules ;  and 
the  height  of  the  entablature,  four 
modules ;  the  Utter  of  which  being 
divided  into  eig^t  parts,  two  of 
them  are  given  to  the  architrave, 
three  to  the  frieze,  and  the  remain- 
ing three  to  the  cornice. 

In  most  of  the  antiques,  the 
Doric  column  is  executed  vrithout 
a  base.  Vitruvius  likewise  makes 
it  without  one;  the  base,  accord- 
ing to  that  author,  having  been 
first  employed  in  the  Ionic  order, 
to  imitate  the  sandal  or  covering 
of  a  woman's  foot.  Scamozzi 
blames  this  practice ;  and  most  of 
the  modems  have  been  of  his 
opinion,  the  greatest  part  of  them 
having  employed  the  Attic  base  in 
this  order. 

Domum  tree,  a  large  beam  lying 
across  a  room ;  a  joist,  or  sleeper 

Dormer  window,  a  window  pierced 
through  a  sloping  roof,  and  placed 
in  a  small  gable  which  rises  on  the 
side  of  the  roof 

Dormitory,  a  sleeping  apartment; 
a  term  formerly  applied  to  the 
sleeping-room  cMf  the  inmates  of 
monasteries  and  other  religious 
houses 

Dormond,  a  large  beam  lying  across 
a  room;  a  joist,  or  sleeper:  same 
asDorman 

Doron,  a  hand -breadth,  or  palm : 
among  the  Greeks,  their  bricks  or 
tiles  were  termed  tetradoron,  four 
hands'  breadth,  or  pentadoron,  five 
hands  broad:  the  word  also  im- 
plies a  gift:  hmce,  probably,  the 
origin  of  the  English  word  dowry 

Dosel,  hangings  round  the  vralls  of  a 
hall,  or  at  the  east  end,  and  some- 
times the  sides,  of  the  cbancel  of 
a  church,  made  of  tapestry  or  car- 
pet-work; used  also  in  churches, 
and  frequently  richly  embroidered 
with  silks,  and  gold  and  silver 


153 


65 


DOS 


DRAINAGE  OF  MARSHES. 


DIL.A. 


Dotei,  oniameDtaL  and  rich  stuif  for 
the  back  of  a  chair,  a  throne,  or  a 
screen  of  ornamental  wood-work 

Double-acting  /wmp,  a  pump  which 
lifts  and  fwces  water  at  the  same 
time,  by  means  of  a  solid  piston, 
and  an  entrance  and  exit-yalve 
communicating  with  each  side 

Dfrnble-beat  vtthe^  a  valve  used  in 
Cornish  engines  and  water-works. 
It  has  two  beats,  or  seatings,  one 
above  ^e  other:  the  bottom  one 
is  similar  to  an  ordinary  circular 
valve  seating;  the  top  one  is  some- 
what less  in  diameter  than  the  bot- 
tom one,  and  is  supported  from  it 
by  ribs,  and  forms  a  cover  nearly 
the  size  of  the  inner  passage.  A 
shell  with  two  beats  to  correspond 
with  the  seatings  shuts  the  sides : 
when  raised,  (which  requires  but 
little  power,  as  the  fixed  cover 
before  mentioned  bears  nearly  all 
the  piessure,  its  diameter  being 
nearly  equal  to  that  of  the  shell,) 
the  steam  or  water  escapes  at  the 
sides  both  of  the  top  and  bottom 
beat. 

Double  cyUnder  enginet  a  marine  en- 
gine with  two  cylinders  placed  at 
.  right  angles  ta  the  crank-shaft,  and 
at  a  small  distance  apart,  to  give 
space  for  the  vibration  of  the  rod 
connecting  the  crank  to  the  long 
end  of  a  shaped  cross-head,  which 
slides  in  grooves  between  the  cy- 
linders :  the  upper  ends  of  the 
cross-head  are  connected  to  the 
piston-rods.  This  form  of  engine 
is  patented  by  Messrs.  Maudsley. 

Dove-tailf  in  carpentry,  a  method  of 
joining  two  boards  together  by 
letting  one  piece  into  another  in 
the  f<mn  of  the  tail  of  a  dove,  when 
that  which  is  inserted  has  ^e  ap- 
pewmce  of  a  wedge  reversed 

DwedaiUngy  a  method  of  fastening 
together  two  pieces  of  metal  or 
wood,  by  projecting  bits  cut  in  the 
form  of  dove-tails  in  one  piece,  to 
fit  into  corresponding  hdlows  in 
the  other 

Dowel  A  round  dowel  or  coak  is 
the  piece  of  timber  to  which  the 

154 


felloes   of  a    carriage-wheel 
united 

Dowsing  eheekst  in  ship-building , 
pieces  fayed  across  the  apron,  ajid 
lapped  on  the  knightheads  ox- 
inside  stuff  above  the  upper  deck. 

Drttft-engine,  an  engine  used  fox- 
pumping 

Drag-dar,  a  strong  iron  rod  witli. 
eye-holes  at  each  end,  connecting 
a  locomotive  engine  and  tender  by- 
means  of  the  drag-bolt  and  spring 

Drag-dolt,  the  strong  bolt  coupling 
the  drag-bar  of  a  locomotive  engine 
and  tender  together,  and  remove- 
able  at  pleasure 

Drag-hook  and  chainf  the  strong  chaii:i 
and  hook  attached  to  the  front  of 
the  engine  buffer-bsr,  to  connect 
it  on  to  any  other  locomotive  en- 
gine or  tender:  also  attached  to 
the  drag-bars  of  goods  waggons 

Drag-Unkf  a  link  for  connecting  the 
cranks  of  two  shafts :  it  is  used  in 
marine  engines  for  connecting  the 
crank  on  the  main-shaft  to  that  on 
the  inner  paddle-shaft 

Drag-spring,  a  strong  spring  placed 
near  the  back  of  the  tender.  It  is 
attached  by  the  ends  to  the  drag- 
bar  which  connects  the  engine  and 
tender,  and  by  the  centre  to  the 
drag-bar  which  connects  the  train 
to  the  tender. 

DragoiCs  blood  (colour),  a  resinons 
substance  brought  from  the  East 
Indies.  It  is  of  a  warm  semi-trans- 
parent, rather  dull-red  colour, 
which  is  deepened  by  impure  air, 
and  darkened  by  light.  There  are 
two  or  three  sorts,  but  that  in  drops 
is  the  best.  White  lead  soon  de- 
stroys it,  and  it  dries  with  extreme 
difficulty  in  oiL  It  is  sometimes 
used  to  colour  varnishes  and  lac- 
quers, being  soluble  in  oils  and 
aloohol;  but  notwithstanding  it  has 
been  recommended  as  a  pigment,  it 
does  not  merit  the  attention  of  the 
artist. 

Drainage  af  marshes  and  fen  tends. 
The  steam  engine  is  used  to  raise 
the  water  above  the  level  of  those 
lands  which  lie  too  low  to  be  drained 


DRA 


DRAINAGE  OP  FENS. 


DRA 


hy  natural  ontfaUy  and  also  in  situ- 
ations where  the  fe^  ia  not  snffident 
to  can7  off  the  superfluous  water 
in  time  to  prevent  damage  to  the 
crops. 

Mr.  Glynn  haa  applied  steam 
power  to  the  drainage  of  land  in 
fifteen  districts,  all  in  England, 
chiefly  in  Cambridgeshire,  Linocdn- 
sfaiie,  and  Norfolk.  The  quantity 
of  land  so  drained  amounts  to  more 
than  125,000  acres,  the  engines  em- 
ployed being  seventeen  in  number, 
and  their  sgg^reggte  power  870 
horses:  the  size  of  the  engines 
Yaries  from  20  to  80  horses.  Mr. 
Glynn  was  also  ^gaged  in  draining 
by  steam  power  the  Hammerforook 
district,  cLwe  by  the  city  of  Ham- 
burgh ;  and  in  another  level  near 
to  Botteidam,  an  engine  and  ma- 
chinery with  the  requisite  buildings 
have  been  erected  fix>m  his  plans  by 
the  GhevaUer  Gonrad,  andthe  wqrks 
successfully  carried  into  effect. 

In  British  Guiana  the  steam  en- 
gine has  been  made  to  answer  the 
double  purpose  of  drainage  and  irri- 
gation. Some  of  the  sugar  planta- 
tions of  Demerara  are  drained  of 
the  superfluous  vrater  during  the 
rainy  reason,  and  watered  during 
the  dry  season. 

In  many  of  the  swampy  levels  of 
lancolnshire  and  Cambridgeshire, 
much  had  been  done  to  carry  off  the 
water  by  natural  means,  and  many 
large  cuts  had  been  made  and  em- 
bankments formed,  espedally  in  the 
Bedford  Level,  which  alone  con- 
tains about  300,000  acres  of  fen- 
land:  the  Great  Level  of  the  fens 
contains  about  680,000,  formerly 
of  little  value,  but  now  rich  in  com 
and  cattle. 

The  general  plan  i»  to  carry  away 
the  water  coming  off  the  higher 
grounds,  and  prevent  it,  as  much 
as  possible,  from  running  down  into 
the  marsh  by  means  of  the  catdi- 
water  drains,  leaving  the  rain  alone 
which  fiUs  upon  ths  district  to  be 
dealt  with  by  mechanical  ])ower. 
As  the  quantity  of  rain  falling  on 


the  Great  Level  of  the  fens  sddom 
exceeds  26  inches  in  the  year,  and 
about  two-thirds  of  tins  quantity  is 
carried  off  by  evaporation  and  ab- 
sorption, or  tiie  growth  of  plants,  it 
is  only  in  extreme  cases  that  2  in- 
ches in  depth  require  to  be  thrown 
off  by  the  engines  in  any  one  month, 
which  amounts  to  H  cubic  foot  of 
vrater  upon  every  square  yard  of 
land,  or  7260  feet  to  the  acre. 

The  standard  and  accepted  mea- 
sure of  a  horse's  power  is  33,0001b8. 
raised  1  foot  high  in  a  minute,  or 
3300  lbs.  raised  10  feet  high  in  the 
same  time ;  and  as  a  cubic  foot  gf 
water  weighs  62i  lbs.,  and  a  gallon 
of  water  10  lbs.,  so  one  horse's  power 
will  raise  and  discharge,  at  a  ha^t 
of  10  feet,  330  gallons,  or  52^ 
cubic  feet  of  water  in  a  minute. 
Consequently  this  assumed  excess 
of  7260  cubic  feet  of  water  fisUen 
upon  an  acre  of  land  will  be  raised 
and  discharged  at  an  elevation  of 
10  feet  in  about  two  hours  and 
twenty  minutes.  If  the  quantity 
of  land  be  1000  acres  of  fen  or 
marsh,  with  the  ujdand  waters  all 
banked  out,  the  excess  of  rain,  ac- 
cording to  the  foregoing  estimate, 
will  amount  to  726,000  cubic  feet. 
A  steam  aigine  of  lO-horse  power 
will  throw  off  this  water  in  232 
hours,  or  in  less  than  twenty  days, 
workhig  twelve  hoars  a  day.  This 
calculation  has  been  found  fully 
supported  in  practice. 

Although  the  rain  due  to  any 
given  month  may  fall  in  a  few  days, 
yet  in  such  case  much  of  it  will  be 
absorbed  by  the  ground;  and  the 
drains  must  be  made  of  sufficient 
capacity  to  receive  and  contain  the 
rain  as  it  fetlls ;  besides,  in  case  of 
necessity,  the  engine  may  be  made 
to  work  twenty  hours  a  day  in- 
stead of  twelve,  until  the  danger  be 
past. 

The  main  drains  have  generally 
been  cut  7i  feet  deep,  and  of  width 
sufficient  to  give  them  the  required 
capacity  to  contain  the  excess  of 
rain,  and  to  bring  the  water  freely 


155 


DRA 


DRAINAGE  OF  FENS. 


DRA 


down  to  the  engine.  In  some  in- 
stances, where  the  districts  are  ex- 
tensive and  their  length  great,  it 
has  heen  found  necessary  to  make 
them  somewhat  deeper. 

In  all  cases  where  it  has  been 
requisite  to  use  steam  power,  Mr. 
Glynn  has  applied  scoop-wheels  to 
raise  thewater.  These  scoop-wheels 
somewhat  resemble  the  undershot 
wheel  of  a  water-mill,  but  instead 
of  being  turned  by  the  impulse  of 
the  water,  they  are  used  to  lift  it, 
and  are  kept  in  motion  by  th&steam 
engine. 

The  floats  or  ladle-boards  of  the 
wheels  are  made  of  wood,  and  fitted 
to  work  in  a  trough  or  track  of 
masonry ;  they  are  generally  made 
5  feet  in  length,  that  is  to  say,  they 
are  immersed  5  feet  deep  in  the 
water,  and  their  width  or  horizontal 
dimension  yaries  from  20  inches  to 
5  feet,  according  to  the  power  of 
the  engines  employed,  and  the  head 
of  water  to  be  overcome.  The 
wheel-track  at  the  lower  end  com- 
municates with  the  main  drain,  and 
at  the  higher  end  with  the  river ; 
the  water  in  the  river  being  kept 
out  by  a  pair  of  pointing  doors, 
like  the  lock-gates  of  a  canal,  which 
close  when  the  engine  ceases  to 
work.  The  wheels  themselves  are 
made  of  cast  iron,  formed  in  parts 
for  convenience  of  transport.  The 
float-boards  are  connected  with  the 
cast-iron  part  of  the  wheel  by  means 
of  oak- starts,  which  are  stepped 
into  sockets  cast  in  the  circum- 
ference of  the  wheel  to  receive 
them. 

There  are  cast-non  toothed  seg- 
ments fitted  to  the  wheel,  into 
which  works  a  pinion  fixed  upon 
the  crank-shaft  of  the  steam  engine. 
When  the  head  of  water  in  the 
river  or  delivering  drain  does  not 
vary  much,  it  is  sufilicient  to  have 
one  speed  for  the  wheel;  but  where 
the  tide  rises  in  the  river,  it  is 
desirable  to  have  two  speeds  or 
powers  of  wheel-work,  the  one  to 
be  used  at  low  water,  the  other 

156  ~" 


more  powerful  combination  to  aet 
against  the  rising  tide.  But  in 
most  cases  it  is  not  requisite  to 
raise  the  water  more  than  3  or  4  feet 
higher  than  the  surface  of  the  land 
intended  to  be  drained ;  and  even 
this  is  only  necessary  when  the 
rivers  are  fdl  between  their  banks, 
from  a  continuance  of  wet  weather, 
or  fh)m  upland  floods. 

In  some  instances,  the  height  of 
the  water  in  the  rivers  being  affected 
by  the  tide,  the  drainage  by  natural 
outfall  can  take  place  only  during 
the  ebb ;  and  here,  in  case  of  long- 
continuing  rains,  the  natural  drain- 
age requires  the  assistance  of  me- 
chanical power. 

It  has  been  stated  that  the  main 
drains  have  generally  been  made 
7i  feet  deep,  or  more  in  larger  dis- 
tricts, so  that  the  water  may  never 
rise  higher  than  within  18  inches 
or  2  feetof  the  surface  of  the  ground, 
and  the  ladles  or  float-boards  dip 
5  feet  below  the  water,  leaving  a 
foot  in  depth  below  the  dip  of  the 
wheel,  that  the  water  may  run  freely 
to  it,  and  to  allow  for  the  casual 
obstruction  of  weeds  in  the  main 
drain,  which,  if  it  be  sufficiently 
capacious  andwell  formed,  wiU  bring 
down  the  water  to  the  engine  with 
a  descent  of  3  inches  in  a  mile. 

Suppose  then  that  the  wheel  dips 
5  feet  below  the  surfiice  of  the 
water  in  the  main  drain,  and  that 
the  water  in  the  river  into  which 
this  vrater  must  be  raised  and  dis- 
charged has  its  level  5  feet  above 
that  in  the  drain,  the  wheel  in  such 
case  will  be  said  to  have  10  feet 
head  and  dip,  and  ought  to  be  made 
28  or  30  feet  in  diameter. 

Mr.  Glynn  has  found  it  i»acti.  { 
cable  to  throw  out  the  water  against 
a  head  of  1 0  feet  with  a  dip  of  5  feet, 
that  is  to  say,  15  feet  of  head  and 
dip,  with  a  wheel  of  35  feet  in  di. 
ameter;  but  in  another  engine,  more 
recently  erected,  he  has  made  the 
wheel  40  feet  in  diameter.  The 
engine  that  drives  this  wheel  is  of 
80-hor8e  power,  and  is  situated  on 


DRA 


DRAINAGE  OF  LANDS. 


DRA 


the  Ten-mile  Bank,  near  littlepool, 
in  the  Isle  of  Ely.  The  largest 
quantity  of  -water  delivered  by  one 
engine  is  from  Deeping  Fen,  near 
Sittlding :  this  fen  contains  25,000 
acres,  and  is  drained  by  two  engines, 
one  of  80  and  one  of  60  horse  power. 
The  80-horse  engine  has  a  wheel 
of  28  feet  in  diameter,  with  float- 
boards  or  ladles  measuring  5^  feet 
by  5  feet,  and  moving  with  a  mean 
Telocity  of  6  feet  per  second;  so 
that  the  section  of  the  stream  is 
27i  feet,  and  the  quantity  dis- 
charged per  second  1(5  cubic  feet; 
equal  to  more  than  4^  tons  of  water 
in  a  second,  or  about  16,200  tons 
of  water  in  an  honr. 

It  was  in  1825  that  these  two 
engines  were  erected,  and  at  that 
time  the  district  was  kept  in  a  half- 
cultivated  state  by  the  help  of  forty- 
four  wind-mills,  the  land  at  times 
being  wholly  mider  water.  It  now 
grows  excellent  wheat,  producing 
from  four  to  six  quarters  to  the 
acre.  In  many  districts,  land  has 
been  purchased  at  from  iS  10  to  £  20 
an  acre,  by  persons  who  foresaw  the 
consequences  of  theseimprovements, 
and  which  they  could  now  sell  at 
from  £  50  to  £  70  an  acre. 

This  increase  in  value  has  arisen, 
not  only  from  the  land  being  cleared 
frY>m  the  injurious  effects  of  the 
water  upon  it,  but  from  the  im- 
proved system  of  cultivation  it  has 
enabled  the  farmers  to  adopt. 

The  fen-lands  in  Cambridgeshire 
and  great  part  of  the  neighbouring 
counties  are  formed  of  a  rich  black 
earth,  consisting  of  decomposed 
vegetable  matter,  generally  frrom 
6  feet  to  10  feet  thick,  although  in 
some  places  much  thicker,  resting 
upon  a  bed  of  blue  gait,  containing 
clay,  lime,  and  sand. 
Draininffj  as  applied  to  lands,  towns, 
and  buildings,  is  the  art  of  drawing 
or  conveying  away  refuse  liquid 
and  other  matters,  the  accumula- 
tion of  which  would  be  detrimental 
to  animal  and  vegetable  existence. 

In  that  department  which  re- 


lates to  lands,  draining  compre- 
hends also  the  methods  of  irriga- 
ting  or  supplying  water  for  agri- 
cultural purposes,  for  which  the 
natural  supply  is  inadequate.  Re- 
ferring to  towns  and  buildings,  this 
art  Indudes  also,  for  the  purpose  of 
thorough  cleansing,  the  artificial 
supply  of  water. 

According  to  this  comprehensive 
definition,  which  will  be  found  to 
have  greater  practical  convenience 
than  any  more  Umited  one,  Drain- 
ing comprises  observations  of  the 
relative  levels  of  districts  and  of 
their  geological  structure ;  of  the 
several  sources  of  water,  and  the 
amount  of  their  products ;  and  the 
construction  and  arrangement  of 
all  the  artificial  appliances  required 
for  the  supply,  conduct,  and  dis- 
posal of  water,  and  for  conveying 
and  dischaiging  refuse  matters 
generally. 

The  sources  of  water  are  rains 
and  the  ocean.  The  former,  pass- 
ing into  the  earth,  descend  along 
the  lowersurfaces,  and  form  streams 
and  rivers;  or  penetrate  into  some 
permeable  media,  and  accumulating 
in  subterranean  depositories,  form 
springs. 

An  examination  of  the  super- 
ficial and  structural  features  of  the 
soil  enables  us  to  estimate  the 
quantity  of  water  present  in  a  dis- 
trict, and  to  determine  the  means 
that  will  be  available  for  supplying 
the  deficiency  or  discharging  the 
excess. 

The  same  observations  afford  ge- 
neral information  required  in  order 
to  arrange  the  artificial  channels, 
drains,  sewers,  &c.,  by  which  the 
supply  and  refuse  matters  are  to 
be  conducted  and  disposed  of. 

Soils  are  retentive  of  water  in 
proportion  to  their  density  and 
compactness.  Thus,  on  clay-lands 
an  excess  of  water  is  commonly 
found,  while,  from  the  porous  tex- 
tures of  gravel  and  loose  sand, 
water  passes  rapidly  away,  and  they 
are  thus  kept  in  a  dry  condition. 


157 


DRA 


DRAWBRIDGE. 


DRA 


The  me  of  the  channels  or 
dranu,  by  which  the  water  is  con- 
ducted away,  will  be  adapted  to  the 
superficial  extent  to  be  drained, 
and  the  quantity  of  water  due  to 
the  district,  as  computed  from  its 
relative  position  and  structure. 
The  corutmctioH  of  the  drains  will 
depend  upon  the  materials  of  the 
sou,  and  the  proximity  of  those 
suitable  for  the  purpose.  Generally, 
covered  drains  are  far  preferable  to 
open  ones;  and  those  formed  with 
a  duct  of  earthen  piping  are  more 
durable  and  economical  than  any 
others.  The  implementt  used  are 
rods  and  levels,  for  measuring  dis- 
tances and  ascertaining  inclinations 
of  surface; — ^tools  for  boring  the 
soil,  to  examine  substrata,  and  de- 
tect springs,  consisting  of  augers, 
chisels,  punches,  &c. ;  —  spades, 
shovels,  and  picks  of  various  forms 
and  dimensions ;  and  hoes,  scoops, 
&c.  for  clearing  out  and  finishing 
the  form  of  drains. 

For  the  draining  of  towns  and 
buildings,  including  the  artificial 
supply  of  water,  the  best  available 
sources — such  as  rivers  and  springs 
— are  resorted  to,  and  the  advan- 
tageous use  of  these  will  require  a 
careful  consideration  of  the  gwHu 
ties  of  the  water  obtained,  and  its 
suitability  for  domestic  and  manu- 
facturing purposes.  Arrangements 
are  required  for  making  the  water 
furnished  by  rains  avidlable  to  the 
full  extent,  and  rendering  it  and  all 
other  waters  fit  for  use  by  subsi- 
dence, filtration,  and  purification. 

For  discharging  the  refuse  mat- 
ters from  houses  and  other  build- 
ings, and  from  streets  and  public 
thoroughfares,  drains  and  sewers 
of  various  forms  and  materials  are 
to  be  selected,  made  of  ample  di^ 
wteneiong  and  permanent  construc- 
tion, with  such  vertical  inclination, 
and  so  arranged,  that  their  con- 
tents shall  always  have  a  tendency 
to  run  ofi",  and  never  suffer  inter- 
ference from  the  discharge  of  other 
channels. 


As  a  final  point  to  be  observed 
in  any  system  of  town-drainage, 
that  of  the  ultimate  disposal  of  the 
refuse  matters  is  one  of  the  highest 
importance  in  both  a  sanatory  and 
an  economical  point  of  view.  Col- 
lected in  proper  reservoirs,  and 
judiciously  treated,  these  matters 
may  be  distributed  in  fertilizing 
streams  over  the  fields  and  the 
gardens  of  the  suburbs,  and  will 
thus  realize  immense  value  in  im- 
proved and  augmented  crops:  al- 
lowed to  accumulate  in  cesspools 
beneath  human  dwellings,  they  en- 
gender malignant  and  fatal  disease, 
and  if  fins^y  discharged  into  a 
river,  by  way  of  getting  rid  of  them, 
they  poUute  waters  otherwise  whole- 
some, \and,  in  dry  seasons,  send 
forth  from  the  baidcs  the  most  un- 
healthy gases. 

Draughty  in  ship  draughting,  the  draw- 
ing or  design  by  which  the  ship  is 
to  be  built,  which  h&  generally  by  a 
scale  of  one-fourth  of  an  indi  to  a 
foot 

Draute-ehambert  a  retiring  or  with- 
drawing room 

DraW'bore,  the  pinning  a  modase  and 
tenon,  by  piercing  the  hole  through 
the  tenon  nearer  to  the  shoulder 
than  the  holes  through  the  cheeks 
from  the  abutment  in  which  the 
shoulder  is  to  come  in  coi^act 

Draw-bore  pinst  pieces  of  steel  in  the 
shape  of  the  frustrum  of  a  cone, 
somewhat  tapered,  and  inserted  in 
handles  vrith  the  greatest  diameter 
next  to  the  handle,  for  driving 
through  the  draw-bores  of  a  mor- 
tise and  tenon,  in  order  to  bring 
the  shoulder  of  the  rail  dose  home 
to  the  abutment  on  the  edge  of  the 
style:  when  this  is  effected,  the 
dniw-bore  pins,  when  more  than 
one  are  used,  are  taken  out  singly, 
and  the  holes  filled  up  vrith  wooden 

Drawbridge.  All  drawbridges  are 
composed  of  two  distinct  parts,  viz. 
the  platform,  which  revolves  on  a 
horizontal  axis,  acting  as  a  barrier 
or  gate  when  in  a  vertical  position, 


158 


■  •*• 


m»m 


DRA 


DRAWING. 


DRE 


I 


and  becoming  a  bridge  when  in  a 
horizontal  position;  and  the  con- 
trivance necessary  to  balance  the 
platform  in  every  position.  The 
equilibrium  should  be  such  that 
friction  is  the  only  force  to  be 
overcome  in  raising  or  loweiing 
the  platform. 

The  chief  difference  between 
drawbridges  lies  in  the  arrange- 
ment of  this  latter  contrivance;  for 
the  platforms  only  differ  in  small 
details  of  construction,  which  have 
very  little  influence  on  the  qualities 
which  are  essential  to  the  arrange- 
ment of  the  balancing  apparatus. 
These  qualities  remain  the  same, 
whether  the  drawbridges  are  used 
for  closing  communications  in  for- 
tified works,  or  merely  for  forming 
passages  across  navigable  canals. 
They  are  principally  as  follows : 

1st.  The  whole  system  should 
possess  sufficient  strength  to  be 
perfectly  free  from  danger  in  all 
positions  and  at  all  times,  and 
should  therefore  be  constructed 
of  solid  and  lasting  materials. 

2nd.  A  small  number  of  men 
should  be  able  to  raise  or  lower 
the  bridge  in  a  short  space  of  time. 
This  quality  requires  all  the  parts 
to  be  in  equilibrium  when  friction 
is  not  considered. 

3rd.  The  machinery  for  raising 
and  lowering  the  bridge  should  not 
obstruct  the  communications  either 
in  front  or  in  rear  of  the  buttresses 
of  the  gateway  where  it  is  placed ; 
and  also  the  space  formed  by  rais- 
ing the  bridge  should  be  as  wide 
as  possible,  for  this  space  consti- 
tutes the  chief  use  of  the  bridge. 

4th.  The  counterpoise  and  the 
machinery  attached  to  it  should  be 
raised  as  Uttle  as  possible  above 
the  platform  when  vertical,  in  or- 
der  that  it  may  not  be  much  ex- 
posed to  an  enemy's  fire,  and  that 
It  may  be  easily  covered  by  the  ad- 
vanced works;  besides  that,  by 
raising  it,  the  expense  of  construct- 
ing and  the  inconvenience  of  work- 
ing the  machinery  are  increased, 

159 


and  the  strength  of  the  gateway  or 
postern  is  scHuetimes  diminished. 

5th.  The  counterpoise  and  its 
machinery  should  not  be  much  be- 
low the  level  of  the  ground,  and 
particularly  very  little  below  the 
level  of  the  surface  of  the  water  in 
wet  ditches.  At  all  events,  the 
descending  parts  should  be  endosed 
in  narrow  shafts  of  masonry  secure 
from  damp.  In  order  not  to  weaken 
the  postern  walls,  they  should  be 
at  least  3  feet  in  rear  of  them. 

Drawing  is  the  art  of  representing 
objects  on  a  flat  surface  by  lines 
describing  their  forms  and  contours 
alone,  independently  of  colour  or 
even  shadow,  although  the  latter 
is  closely  allied  with  drawing,  both 
in  practice  and  theory 

Drawings  in  pencil  are  sometimes  re- 
quired to  be  fixed:  this  can  be 
done  by  using  water-starch  made 
to  the  consistency  of  that  employed 
by  laundresses:  it  should  be  q»- 
plied  vrith  a  broad  camel's  hidr 
brush,  as  in  varnishing.  Isinglas 
size,  and  rice-water,  are  sometimes 
used,  but  are  not  so  good  as  the 
first-named  substance. 

Dredge*9  Sutpension  Bridge  consists 
in  making  the  chains  of  sufficient 
magnitude  and  strength  at  the 
points  of  suspension  to  support 
with  safety  the  greatest  permanent 
and  contingent  load  to  which,  un- 
der the  circumstances  oi  locality, 
they  are  ever  likely  to  be  exposed; 
and  from  thence,  to  taper  or  dimi- 
nish them  gradually  to  the  middle 
of  the  bridge,  where  the  strain  be- 
comes essentially  evanescent.  The 
gradual  diminution  of  the  chains, 
however,  is  not  the  only  peculiarity 
which  characterizes  this  mode  of 
construction,  and  marks  its  utility. 
The  suspending-rods  or  bars  that 
support  the  platform,  or  roadway, 
instead  of  being  hung  vertically  or 
at  right  angles  to  the  plane  of  the 
horizon,  are  inclined  to  it  in  angles 
which  vary  in  magnitude  from  the 
abutments  to  the  middle  of  the 
bridge,  where  the  obliquity,  as  well 


DRE 


DRUMMOND  LIGHT. 


DRY 


as  the  stress  upon  the  chains,  at- 
tains its  minimum  value. 

Dredging  macMnes,  mechanical  con- 
trivances placed  in  the  hull  of  a 
vessel,  and  floated  in  situations  for 
the  dredging  and  clearing  away  of 
deposited  matter  from  the  beds  of 
rivers,  canals,  harbours,  basins,  &c. 
Some  machines  for  these  purposes 
are  to  be  compared  to  harrows  or 
shovels,  which  loosen  the  deposit 
preparatory  to  its  removal  either 
by  the  action  of  the  tide  or  stream; 
but  for  the  more  general  purposes 
of  dredging,  vast  improvements 
have  been  effected.  The  machinery 
of  the  best  construction  is  described 
in  Weale's  '  Quarterly  Papers  on 
Engineering.' 

DressingSt  the  mouldings  and  sculp- 
tured decorations  of  all  kinds  which 
are  used  on  the  walls  and  ceilings 
of  a  building  for  the  purpose  of  or- 
nament 

Driftf  a  piece  of  hardened  steel, 
notched  at  the  sides  and  made 
slightly  tapering:  it  is  used  for 
enlarging  a  hole  in  a  piece  of  metal 
to  a  particular  size  by  being  driven 
through  it 

Driftt  the  horizontal  force  which  an 
arch  exerts  with  a  tendency  to 
overset  the  piers  from  which  it 
springs 

DHftSi  in  the  sheer  draught,  are 
where  the  rails  are  cut  off  and 
ended  with  a  scroll.  Pieces  fitted 
to  form  the  drifts  are  called  drift- 
pieces. 

Driftway  t  in  mining,  is  a  passage  cut 
under  the  earth  from  shaft  to  shaft 

Drills  a  tool  for  cutting  a  circular 
hole  in  a  piece  of  meted 

Drilling  machine^  a  machine  for  cut- 
ting circular  holes  in  metal  by 
means  of  a  revolving  drill 

DrilUngy  the  art  of  boring  small  holes. 
Drilling  may  be  effected  in  a  lathe. 
The  driU  is  screwed  upon  the  spin- 
dle, so  that  its  point  shall  turn  ex- 
actly opposite  that  of  the  screw  in 
the  shifting  head.  Various  inge- 
nious improvements  have  recently 
been  made. 

160 


Drip,  the  projecting  edge  of  a  mould- 
ing channeled  beneath,  so  that  the 
rain  will  drip  from  it :  the  corona 
of  the  Italian  architects 

Dripstone^  called  also  the  'label,' 
*  weather  moulding,'  and  'water 
table,'  a  projecting  tablet  or  mould- 
ing over  the  heads  of  doorways, 
windows,  archways,  niches,  &c. 

Drioer,  the  foremost  spur  in  the 
bulge-ways,  the  heel  of  which  is 
fayed  to  the  foreside  of  the  fore- 
most poppet,  and  the  sides  placed 
to  look  fore  and  aft  in  a  ship 

Driver^  the  bent  piece  of  iron  fixed  in 
the  centre  chuck,  and  projecting 
over  it  to  meet  the  carrier,  and 
drive  it  forward 

Driving  ihaft,  any  shaft  which  gives 
motion  to  another  shaft 

Driving  apringSf  the  springs  fixed 
upon  the  boxes  of  the  driving  axle 
of  a  locomotive  engine,  to  support 
the  weight  and  to  deaden  the 
shocks  caused  by  irregularities  in 
the  rails 

Driving  wheela,  the  large  wheels  of  a 
locomotive  engine,  which  are  fixed 
upon  the  crank-axle,  or  main  shaft 
of  the  engine 

Drumy  in  architecture,  thebell-formed 
part  of  the  Corinthian  and  Compo- 
site capitals 

Drum,  a  hollow  cylinder  fixed  on  a 
shaft,  for  driving  another  shaft  by 
a  band 

Drummond  lights  a  peculiar  light 
invented  by  the  late  Capt.  Drum- 
mond, called  a  heliostat,  which  re- 
flected the  sun's  rays  in  sufllcient 
abundance  to  render  the  station 
which  was  to  be  observed  visible. 
This  invention  obviated  the  difll- 
culty  of  distinguishing  the  stations 
chosen  for  the  angular  points  of 
the  triangles  in  a  geodesical  sur- 
vey :  where  those  stations  are  many 
mUes  asunder,  it  is  necessary  to 
have  recourse  to  illuminations  even 
in  day-time. 

Dnutey,  timber  in  A  state  of  decay, 
vrith  white  spongy  veins 

Dryness  is  a  term  by  which  artists 
express  the  common  defect  of  the 


DRY 


DYNAMICS. 


DYN 


early  painters  in  oil,  who  had  but 
little  knowledge  of  the  flowing  con- 
toora  which  so  elegantly  show  the 
delicate  forms  of  the  limbs  and  the 
insertion  of  the  muscles ;  the  flesh 
in  their  colouring  appearing  hard 
and  stiff,  instead  of  expressing  a 
pleasing  softness.  The  draperies 
of  those  early  painters,  and  parti- 
cularly of  the  Germans,  concealed 
the  limbs  of  the  figures,  without 
truth  or  elegance  of  choice;  and 
even  in  their  best  nuisters,  the  dra^ 
peries  very  frequently  either  de- 
meaned or  encumbered  the  figures. 

Dry-rotf  a  disease  affecting  timber, 
and  particularly  the  oak  employed 
for  naval  purposes.  Many  contri- 
vances are  employed  as  remedies 
which  have  recently  been  patented, 
and  have  been  successfully  applied. 

Dubf  to  work  with  the  adze 

DuctiUmeier,  an  instrument  for  com- 
paring the  ductility  of  lead,  tin,  &c. 

DuctiKty  is  that  property  of  bodies 
which  admits  of  their  being  drawn 
out  in  length,  while  their  diameter 
is  diminished,  without  any  actual 
fracture.  Gold,  silver,  platinum, 
iron,  copper,  zinc,  tin,  lead,  nickel, 
are  ductile  in  the  order  here  given : 
wire-drawing  depends  on  ductility. 

DuctiUty,  the  property  possessed  by 
certain  bodies  of  yielding  to  percus- 
sion, and  receiving  a  change  of  form 
without  breaking 

Dunu  (in  Cornish),  frames  of  wood 
like  the  jambs  of  a  door  or  the 
friune  of  a  window;  set  in  loose 
ground  in  adits  and  places  that  are 
weak  and  liable  to  fall  in  or  tumble 
down 

Dungeon,  a  place  of  incarceration,  for- 
merly the  principal  tower  or  keep  of 
a  castle :  it  was  always  the  strongest 
and  least  accessiblepart  of  a  building 

Durbar  (Persian),  a  court  or  building 
where  the  sovereign  or  viceroy  gives 
audience 

Dutch  Pink,  EngUsh  and  Italian 
Pinks,  are  bright  yellow  colours 
used  in  distemper  and  for  paper- 
staining,  and  other  ordinary  pur- 
poses.   The  pigment  called  *  stil,' 

161 


or  '  stil  de  grain,'  is  a  similar  pre- 
paration, and  a  very  fugitive  yellow, 
the  darker  kind  of  wUch  is  called 
Brown  Pink. 

Butch  School  of  Patntkig, -^Tloi 
school  of  art  cannot  be  said  to 
possess  the  perfections  that  are  to 
be  observed  in  the  Flemish  school ; 
their  subjects  are  derived  frx)m  the 
tavern,  the  smith's  shop,  and  from 
vulgar  amusements  of  the  rudest 
peasants.  The  expressions  are  suf- 
ficiently marked ;  but  it  is  the  ex- 
pression of  passions  which  debase, 
instead  of  ennobling  human  nature. 
It  must  be  acknowledged,  at  the 
same  time,  that  the  Dutch  painters 
have  succeeded  in  several  branches 
of  the  art.  If  they  have  chosen  low 
subjects  of  imitation,  they  have  re- 
presented them  with  great  exact- 
ness; and  truth  must  always  please. 
If  they  have  not  succeeded  in  most 
difficult  parts  of  the  chiaro-oscuro, 
they  at  least  excel  in  the  most 
striking,  such  as  in  light  confined 
in  a  narrow  space,  night  illuminated 
by  the  moon,  or  by  torches,  and  the 
light  of  a  smith's  forge.  The  Dutch 
understand  the  gradations  of  colours. 
They  have  no  rivals  in  landscape 
painting,  considered  as  the  faithful 
representation  of  a  particular  scene ; 
but  they  are  far  from  equalling 
Titian,  Poussin,  Claude  Lorraine, 
&c.,  who  have  carried  to  the 
greatest  perfection  the  ideal  land- 
scape ;  and  whose  pictures,  instead 
of  being  the  topographical  repre- 
sentation of  certain  places,  are  the 
combined  result  of  every  thingbeau- 
tiful  in  imagination  or  in  nature. 

Dyeing  is  the  art  of  staining  textile 
substances  with  permanent  colours 

Dyke,  in  coal  mining,  the  banks  of 
basalt  or  whin,  by  which  the  coal 
strata  are  frequently  divided 

Dynamics,  the  science  of  moving 
powers,  or  of  the  action  offerees  on 
solid  bodies  when  the  result  of  that 
action  is  motion. 

GENERAL   DEFINITIONS. 

1.  The  mass  of  a  body  is  the 
quantity  of  matter  of  which  it  is 


DYN 


EARLY  ENGLISH  ARCHITECTURE. 


DYS 


composed,  and  is  proportional  to  its 
weight,  or  to  the  ybrce  which  must 
be  applied  to  the  body  to  prevent 
its  gravitating  to  the  earth,  and 
which,  being  greater  or  less  as  the 
mass  is  greater  or  less,  we  regard 
as  a  measure  of  the  mass  itself. 

2.  Density  is  a  word  by  which 
we  indicate  the  comparative  close- 
ness or  otherwise  of  the  particles  of 
bodies,  and  is  synonymous  with  the 
iexm  specific  gravity.  Those  bodies 
which  have  the  greatest  number  of 
particles,  or  the  greatest  quantity 
of  matter,  in  a  given  magnitude,  we 
call  most  dense  f  those  which  have 

"the  least  quantity  of  matter,  least 
dense.  Thus  lead  is  more  dense 
than  freestone;  freestone  more 
dense  than  oak;  and  oak  more 
dense  than  cork. 

3.  The  velocity  with  which  a 
body  in  motion  moves,  is  measured 
by  the  space  over  which  it  passes  in 
any  given  time;  the  unit  usually 
assumed  being  one  second, 

4.  If  the  body  passes  over  an 
equal  space  in  each  successive  unit 
of  time,  the  body  is  said  to  move 
uniformly f  or  to  have  a  vn\fbrm 
velocity f  and  the  measure  of  such 
velocity  is  the  space  actually  passed 
over  by  the  body  in  each  second. 

5.  If,  however,  the  body  passes 
over  a  greater  space  in  each  suc- 
cessive second  than  it  did  in  the 
preceding,  then  it  is  said  to  move 
with  an  accelerated  velocity :  when 
the  differences  between  the  spaces 
moved  over  in  any  two  successive 
seconds  is  the  same,  at  whatever 
period  of  the  body's  motion  they  be 
taken,  or  in  other  words,  when  the 
successive  spaces  form  an  arithme- 
tical progression,  the  body  is  said 
to  move  with  a  vniformly  accele- 
rated velocity  ;  but  when  the  spaces 
passed  over  in  successive  seconds 


EAR 
Early  English  Architecture^  the  first 
of  the  pointed  or  Gothic  styles  of 
architecture  used  in  Engknd.    It 

162       ' 


increase  according  to  any  other  la^r, 
the  body  is  then  said  to  have  its 
velocity  variably  accelerated. 

6.  If,  on  the  other  hand,  the  body 
passes  over  a  smaller  space  in  each 
successive  second  than  it  did  in  the 
preceding,  then  it  is  said  to  moTc 
vnth  a  retarded  velocity ;  which,  if 
the  successive  spaces  form  a  de> 
creasing  arithmetical  series,  is  said 
to  be  uniformly  retarded;  it  other- 
wise,itissaidtobeoarta^/yre^ar<2ie<f. 

7.  The  velocity  of  a  body  whose 
motion  is  yariable  is  expressed  at 
any  moment  by  the  space  which  it 
would  pass  over  in  a  second,  if  its 
velocity  at  the  moment  spoken  of 
were  to  continue  un^orm  for  that 
period. 

8.  ilfecAantca/ ^ec/ is  measured 
by  the  product  of  the  mass  or 
weight  of  the  body  into  the  space 
over  which  it  has  been  moved ;  no 
regard  being  had  to  the  time  occu- 

.  pied.  The  unit  of  mechanical  effect 
is  a  weight  of  one  pound  raised 
through  a  space  of  one  foot. 

9.  The  momentum  of  a  body  in 
motion  means  the  mechanical  effect 
which  such  a  body  will  produce  in 
a  moment  (or  second)  of  time,  and 
varies  as  the  weight  of  the  body 
multiplied  by  its  velocity, 

10.  The  vis  viva  of  a  body  in 
motion  is  the  whole  mechanical 
effect  which  it  viriU  produce  in 
being  brought  to  a  state  ofresty  no 
regard  being  had  to  the  time  in 
which  the  effect  is  produced,  and 
it  varies  as  the  weight  of  the  body 
multiplied  by  the  square  of  its 
velocity. 

Dynamometer^  an  instrument  which 
measures  any  thing  to  which  the 
name  of  power  has  been  given, 
whether  that  of  an  animal  or  other- 
vnse 

Dysodile,  a  papyraceous  brown  coal 


EAR 
immediately  succeeded  the  Norman 
towards  the  end  of  the  12th  cen- 
tury, and  gradually  merged  into 


the  Decorated  at  the  end  of  i 
13th.  The  mouldingi  eonsial 
alternate  rouDils  and  deeply  c 
hollowa,  with  smaU  fillets,  pi 
ilucing  a  strong  etFect  of  ligtit  ai 
ihadnw.  The  arcbea  ire  usually 
eq  uilateral  or  Ian  ced-iVi  iped,  tho  ugti 
drup-arclieB     are     frequently    i 


:   trefoil 


ci  seg- 


mented arches 
fpil  arches  are  also  often  used 
small  openings  and  poiieliofp. 
The  doon«ayB  of  tkia  style,  in 
large  buildings,  are  often  divided 
into  two  by  a  single  shaft  or  small 
pin,  with  a  quatre-foil  or  otlier 
ornament.  The  windows  are  al- 
most UDitcraally  of  long  and  narrow 
proportions,  anil  are  used  singly, 
or  ID  combinations  of  two,  three, 
five,  and  seven  :  when  thus  com- 
Uined,  the  space  hetweeu  them 
i  but  little  eiceeds  the 
lidth  of  the  niullions  of  the  later 
tyles.     Groined  ceUings  are  very 


ORK.  EAR 

common  in  this  style.  The  pillo» 
usually  eonsitt  of  small  shafts  u 
ranged  round  a  larger  circular  pier, 
but  others  of  a  different  kind  ire 
sometimea  found.  The  capitals 
consist  of  plain  mouldin^B.  or  are 
enriched  with  foliage  and  seulpture 
characteristic  of  the  style. 
ir/4-inor*.  The  patented  eicaiator, 
originally  an  American  invention, 
is  capable  of  cutting  and  leielling 
earth-work  for  the  making  i  ' 
ways  and  for  other  works  at 
considerably  below  manual  I 
and  which  has  the  additional  ad- 
vantage of  saving  much  tii 
forms  aa  important  consideration 
in  railway  making. 

By  the  attendance  of  the  ei  ^ 
man  and  assistant,  together  with 
the  laboiu'  of  six  men  for  i 


EAR 


EARTH-WORK. 


EAS 


12«.  per  diem.  The  cost  of  the 
machine  is  £1500.  Earth-work 
in  England  has  generally  been 
taken  at  lOd.  to  Is,  per  yard. 

This  apparatus  is  a  strong  rect- 
angular frame  of  wood,  or  other 
material,  mounted  upon  wheels, 
supported,  together  with  the  ma- 
chine, on  a  temporary  railroad: 
at  one  end  of  this  frame  is  a  strong 
crane,  consisting  of  a  vertical  shaft 
or  pillar,  with  the  jib  supported  by 
diagonal  stays,  or  arms  :  to  the 
end  of  the  chain  tackle  is  suspended 
a  scoop,  shovel,  or  scraper,  made 
of  strong  boiler-plate  iron,  and 
consisting  of  two  sides,  end,  and 
bottom,  the  edge  of  which  latter  is 
provideid  with  four  or  more  pro- 
jecting points  or  cutters ;  and  be- 
tween these,  and  at  their  roots,  is 
a  steel  edge,  well  tempered,  so  as 
to  resist  stone  or  other  hard  sub- 
tance  with  which  it  may  come  in 
contact:  the  chain  tadde  is  at- 
tached to  the  sides  of  the  shovel, 
and  passes  over  a  pulley  at  the  end 
of  the  jib,  and  over  another  pulley 
fixed  on  the  top  of  the  pillar  or 
support  of  the  crane,  and  from 
thence  to  the  barrel,  upon  which 
it  is  made  to  coil :  the  periphery 
of  the  last-mentioned  pulley  is 
formed  with  indentations  to  receive 
the  links  of  the  chain,  for  the  pur- 
pose of  giving  motion  to  the  pulley, 
which  has  on  its  axis  a  bevel- 
wheel,  taking  into  and  driving  a 
similar  wheel,  upon  the  end  of  an 
inclined  shaft,  which  shaft  actuates 
certain  machinery  fixed  to  and 
supported  by  the  diagonal  arms  of 
the  crane.  This  machinery  con- 
sists of  a  barrel,  with  other  appur- 
tenances, round  which  is  passed  a 
chain,  with  its  ends  attached  to 
the  opposite  ends  of  a  beam  or 
arm,  which  is  also  fixed  to  the 
shovel  or  scraper.  The  crane  is 
capable  of  being  moved  round,  so 
as  to  turn  the  scoop,  when  ele- 
vated, either  to  the  right  or  left,  in 
a  horizontal  direction  :  for  this 
purpose   a    *  horse- shoe  pulley,  * 

164 


having  a  groove  in  its  periphery,  is 
affixed  to  the  upper  part  of  the 
crane:  a  chain,  attached  at  each 
end  to  a  transverse  bar,  passes 
round  this  pulley,  and  over  certain 
horizontal  and  vertical  guide  pul- 
leys, to  a  barrel,  in  such  a  manner 
that,  by  reversing  the  motion  of 
the  barrel,  the  jib  of  the  crane  can 
be  turned  either  to  the  right  or 
left.  A  steam  engine  is  erected  at 
one  end  of  the  rectangular  frame, 
or  platform,  for  the  purpose  of 
giving  motion  to  the  various  parts 
of  the  apparatus.  When  com- 
mencing operation,  the  shovel,  or 
scraper,  is  suspended  by  the  chain 
tackle  in  a  nearly  vertical  position, 
with  the  steel  points  towards  the 
ground :  by  releasing  the  clicks, 
or  catches,  of  the  chain  barrel,  and 
applying  the  brake,  the  shovel  will 
be  lowered,  and  force  itself,  by  its 
own  weight,  into  the  ground ;  then 
by  communicating  motion  to  the 
chain  barrel,  the  tackle  will  be 
raised,  and,  by  means  of  the  in- 
dented grooved  pulley,  motion  will 
be  given  to  the  shaft,  which  ac- 
tuates the  machinery  on  the  dia- 
gonal arms,  which  in  its  turn  will 
force  forward  the  shovel  into  the 
ground.  At  the  same  time  that  this 
motion  is  going  forward,  the  sho- 
vel, or  scraper,  is  being  raised  or 
lifted  up  by  the  tackle,  by  which 
means  the  shovel  has  a  double 
motion, — a  thrusting  forward  mo- 
tion and  a  lifting  motion.  When 
the  shovel  has  become  filled,  and 
attained  its  proper  altitude,  these 
motions  stop ;  and  the  shovel  being 
prevented  from  returning  by  the 
clicks,  or  catches,  the  other  barrel 
is  thrown  into  gear  by  means  of  a 
coupling  or  clutch-box,  and  the 
crane  turned  round  so  as  to  bring 
the  shovel  over  the  cart,  or  other 
place  of  deposit;  and  by  certain 
arrangements  it  is  turned  up  so  as 
to  empty  itself;  in  which  position 
it  is  again  ready  for  another 
operation. 
Eagel^    for  painters,  the  frame    on 


EAS 


EFFECTS  OF  BUILDINGS. 


EFF 


which  the  canvas  is  laid,  stretched 
for  painting 
East  Indian  Black  taood  grows  to  an 
immense  size,  and  is  much  osed  for 
making  furniture 
Easier,  a  moveable  fesst  held  in  oom- 
memoration  of  the  Resurrection. 
Being  the  most  important  and  most 
ancient  in  observance,  it  governs 
the  other  moveable  feasts  through- 
out the  year. 
Emest  the  lower  edge  of  a  sloping 
roof  which  overhangs  the  face  of 
a  wall,  for  the  purpose  of  throwing 
off  the  water 
Ebony  wood  is  of  several  colours,  as 
yellow,  red,  green,  and  black.  The 
latter  is  always  preferred,  and  is 
much  used.     It  is  imported  princi- 
pally from  the  East,  and  is  used  for 
cabinet,  mosaic,  and  turnery  work, 
for  flutes,  handles  of  doors,  knives, 
surgeons'  instruments,  piano-forte 
keys,  &c. 
Eborariusy  a  term  applied  by  the  Bo- 
mans  to  a  kind  of  ivory-work 
Eccentric t  or  Excentrict  a  circular  disc 
revolving  within  a  strap  or  ring, 
and  having  its  axis  of  revolution 
on  one  side  of  the  centre.    It  is 
used  as  a  substitute  for  a  crank  for 
giving  a  reciprocating  motion  to 
the  slide-valve  or  to  the  feed-pump 
of  a  steam  engine. 
Eccentria  are  circular  sheaves  with  a 
hole  for  the    driving-wheel  axle, 
about  2  inches  out  of  the  centre  of 
the  sheave  of  a  locomotive  engine, 
which  thus  makes  it  project  some 
4  inches  more  from  the  centre  of 
the  driving  axle  on  one  side  than 
on  the  other.  It  is  this  eccentricity 
of  motion  which  works  the  slide- 
valve  gear  and  pumps  in  a  very 
satisfactory    manner.     Eccentrics 
are  fitted  in  two  parts,  and  secured 
to  the  axle  by  a  hoop  and  set- 
bolts. 
Eccentric  hocpSt  hoops  fitted  round 
the  projecting  part  of  the  eccentric 
sheaves  of  a  locomotive  engine,  to 
strengthen  them 
Eccentric  rod  and  strqt,  the  rod,  the 
strap  end  of  which  encircles  the 

165 


eccentric  sheave,  and  the  other  end 
connects  it  with  the  quadrant,  or 
rocking-shaft,  according  to  the 
class  (rf  a  locomotive  engine.  In 
some  engines  the  end  is  forked  to 
go  on  tiie  stud  of  the  rocking- 
i^aft,  and  opens  out  something 
like  the  letter  V;  or  when  only 
one  rod  is  used  for  both  back  and 
forward  movements,  it  resembles 
the  letter  X.  In  other  engines  it 
is  attached  to  the  quadrants  by  a 
bolt,  one  rod  for  forward  gear,  and 
another  rod  for  backward  gear. 

Eccentric  rod,  the  rod  connecting  the 
eccentric  strap  to  the  lever  which 
moves  the  slide-valve 

Eccentric  ttrapf  a  brass  ring  formed 
by  two  pieces  bolted  together,  and 
fixed  to  the  eccentric  rod:  the 
ring  fits  a  grooved  part  in  the  cir- 
cumference of  the  eccentric 

Echintt8f  the  egg  and  anchor,  or  egg 
and  tongue  ornament  found  carved 
on  the  ovolo,  in  classical  architec- 
ture 

EchimUf  a  member  of  the  Doric  capi- 
tal ;  so  called  from  its  resemblance 
to  the  echinus,  or  large  vase,  in 
which  drinking-cups  were  washed 

Eephora,  the  projection  of  any  mem- 
ber or  moulding  before  the  face  of 
the  member  or  moulding  next  be- 
low it 

Educiion  p^,  the  pipe  from  the  ex- 
haust passage  of  the  cylinder  to  the 
condenser 

Efect  is  the  art  of  giving  to  a  draw- 
ing a  striking  appearance,  or  so- 
lemnity, awe,  sadness,  mirth  or 
tranquillity,  by  a  judicious  combi- 
nation of  objects,  and  by  strong 
light  and  shadow.  It  is  a  faithful 
representation  of  the  appearance  of 
nature,  best  seen  under  certain  cir- 
cumstances and  at  certain  times, 
such  as  morning  effect,  evening 
effect,  twilight  effect,  and  stormy 
effect,  torch-light  and  candle-light 
effects,  &c. 

Efects  €f  buildings.  "  The  site  adap- 
ted for  buildings,  and  the  accompa- 
niments of  terraces,  gardens,  and 
other  decorations  to  set  off  their 


EGY 


EGYPTIAN  ARCHITECTURE. 


ELA 


architectural  designSi  are  subjects 
for  consideration  in  which  we  are 
influenced  by  the  desire  to  raise 
and  extend  the  theory  and  practice 
to  what  we  consider  belongs  to  the 
art.   It  was  in  Italy,  when  the  fine 
arts  were  in  perfection,  that  the 
laying  out  great  yiUas  was  prac- 
tised by  artists  who  often  combined 
the  practice  of  painting  and  archi- 
tecture ;  and  until  it  be  adopted  in 
England,  the  designs  of  the  archi- 
tect ne^er  will  have  justice  done  to 
them  in  the  execution.    Our  parks 
may  be  beautiful,  our   mansions 
faultless  in  design ;  but  nothing  is 
more  rare  than  to  see  the  two  pro- 
perly connected.  Let  the  architect 
by  study  and  observation  qualify 
himself  to  include  in  his  fu*t  the 
decorations  around  the  immediate 
site  of  the  intended  building,  toge- 
ther with  its  interior  adornment, 
furniture,  and  upholstery,  and  the 
growing  taste  among  the  gentry  of 
England  will  second  such  laudable 
efforts." 
Egyptian  Architecture  had  its  origin 
2222  years  before  Christ,  and  ad- 
vanced and  flourished  under  dif- 
ferent dynasties.  The  first  includes 
the  two  great  dynasties  of  Theban 
princes,  who  governed  Egypt  dur- 
ing her  ''most  high  and  palmy 
state,"  when  Thebes  sent  forth  her 
armies  to  distant  conquest.    In  the 
second  period    is   comprised  the 
erection  of  the  Pyramids.      The 
third  includes  the  reigns  of  the 
Ptolemies  and  earlier  Caesars,  un- 
der  whom  Egyptian  architecture 
flourished  in  a  second  youth,  and 
almost  attained  its  original  splen- 
dour.   Egyptian  architecture,   so 
massive  and  so  sombre,  with  its 
yast  aisled  halls  yrithout  windows, 
its  close  files  of  gigantic  columns, 
and  its  colossal  statues,  owes  many 
characteristic  forms  and  effects  to 
earlier  cavern  temples  in  Ethiopia. 
One  of  the  most  striking  peculiari- 
ties of  the  style  is  the  pyramidal 
character  of  the  ascending  lines : 
it  is  observed  in  the  outline  of  the 


portal  and  the  gigantic  pylon,  in 
walls,  doorways,  pedestals,  and 
screens:  it  pervades  the  whole 
system,  and  must  have  been  occa- 
sioned by  circumstances  connected 
with  its  origin.  The  representa- 
tions given  in  ancient  paintings 
show  a  remarkable  love  of  uniform- 
ity of  arrangement  of  their  do- 
mestic houses  and  gardens.  In  an 
ordinary  house  a  number  of  cham- 
bers were  ranged  round  a  rectan- 
gular court,  as  at  Pompeii.  The 
larger  mansions  sometimes  consist- 
ed of  an  assemblage  of  such  courts, 
the  whole  occupying  a  square  or 
oblong  plot.  Sometimes  a  central 
group  of  buildings  was  surrounded 
by  a  narrow  court.  A  spacious  area 
often  extended  from  front  to  rear, 
with  a  chief  and  side  entrances  at 
either  end:  the  exterior  had  no- 
thing of  the  ponderous  character 
of  temple  structures,  which  would 
have  been  ill-suited  to  the  wants 
and  festivities  of  social  life.  Houses 
two  and  three  stories  high  were 
common;  but  large  mansions  ap- 
pear to  have  been  low  and  extensive 
rather  than  lofty.  The  terraced 
top  was  covered  by  an  awning  or 
roof,  supported  on  light  graceful 
columns. 

Eidoffraph,  an  instrument  contriyed 
for  the  purpose  of  copying  draw- 
ings 

Ekeing,  in  ship-building,  a  piece  fitted 
to  make  good  a  deficiency  in  length 
on  the  lower  part  of  the  supporter 
under  the  cat-head,  &c. ;  likewise 
the  piece  of  carved  work  under  the 
lower  end  of  the  quarter-piece  at 
the  aft  part  of  the  quarter -gal- 
lery 

EkutiCf  springy,  having  the  power  of 
returning  to  the  form  from  which 
it  was  distorted 

Elastic  force  of  steam.  The  French 
reckon  an  atmosphere  to  be  equal 
to  a  column  of  mercury  *76  of  a 
metre  in  height,  which  is  only 
29*92  inches,  and  the  boiling  point 
of  their  thermometer  is  adapted 
thereto;  whereas,  since  about  the 


166 


ELD 


ELEMENTARY  INSTRUCTION. 


ELE 


commencement  of  the  present  cen- 
tury, the  English  have  reckoned  it 
to  he  30  inches.  This  circumstance 
accounts  in  some  degree  foir  their 
scale  of  temperatures  differing  from 
Mr.  Southern's. 

The  French  account  of  the  occa- 
sion of  making  their  experiments 
on  the  temperatures  corresponding 
to  different  elasticities  of  steam,  in 
1829,  contains  the  following  pas- 
sage :  "  Science  did  not  then  pos- 
sess this  knowledge,  and  engineers 
appointed  to  superintend  the  con- 
struction of  steam  engines  had  no 
other  guidance  than  some  discord- 
ant measures  upon  the  tempera- 
tures which  correspond  to  the  elas- 
ticities between  one  and  eight  at- 
mospheres: for  higher  pressures 
there  was  no  result  of  direct  expe- 
riments, nor  any  theory  which 
could  supply  the  deficiency." 

Eider  wood.  The  branches  of  the  elder 
contain  a  very  light  kind  of  pith, 
which  is  used,  when  dried,  for  elec- 
trical purposes ;  the  wood  is  also 
frequently  used  for  carpenters' 
rules,  weavers'  shuttles,  &c. 

Electrical  state   of  the  atmosphere. 
The  electrical  condition  of  the  air 
in  serene  and  tempestuous  weather 
has  been  too  much  overlooked  by 
meteorologists.     The  atmosphere 
is  generally  found  to  be  in  an  elec- 
trical   state.     The    apparatus  for 
these  observations  is  simply  a  me- 
tallic rod,  insulated  at  its  lower 
extremity,  elevated  at  some  height 
above  the  gp*ound,  and  communi- 
cating with  an  electroscope.  When 
the  amenity  of  the  weather  will 
permit,  a  kite  should  be  raised,  in 
the  string  of  which  a  metalKc  wire 
should  be   interwoven:   this  will 
collect  the  electricity  of  the  higher 
regions  of  the  air.  The  atmosphere 
is  usually  found  to  be  positively 
electrified,    and  its  electricity  is 
stronger  in  the  winter  than  in  the 
summer ;  and  during  the  day  than 
in  the  night. 
Electricity  (from  eUctrum^  amber), 
was  a  name  given  at  first  to  some 


peculiar  effects  observed  on  rub- 
bing that  substance,  and  gradoally 
extended  to  an  immense  collection 
of  facts  of  a  similar  kind,  as  well 
as  to  the  cause  of  these  effects, 
whatever  it  may  be,  and  to  the 
science  which  investigates  their 
laws. 

This  science  is  sometimes  divided 
into  five  or  six  branches,  according 
to  the  modes  in  which  electric  ef- 
fects may  be  brought  about.  The 
term  atmospheric  electricity  applies 
to  that  which  is  naturally  exhibited 
at  nearly  all  times,  but  especially 
in  thunder-storms;  common  or 
frictional  electricity,  to  that  deve- 
loped by  mere  mechanical  actions ; 
gahafiism  or  voltaic  electricity,  to 
that  developed  by  chemical  action; 
/A«rmo-electricity«  by  the  action  of 
heat;  mo^pyi^/o-electricity,  by  that 
of  magnetism ;  and  animal  electri- 
city, by  the  vrill  of  certain  fishes, 
wMch  use  this  power  as  a  defence. 
A  more  modem  and  comprehensive 
division  is  into — 1.  Electro-statics, 
or  tensional  electricity,  referring  to 
those  effects  in  which  the  agency 
seems  to  have  the  equilibrium  of 
its  distribution  disturbed,  so  as  to 
be  excessive  or  deficient  in  certain 
bodies,  making  them  appear  in  dif- 
ferent states.  2.  Electro-dynamics, 
or  current  electricity,  describing 
those  effects  in  which  the  agency 
appears  to  be  moving  from  place  to 
place,  and  displaying  momentum. 

Electrum,  from  the  Greek,  a  name 
given  to  amber,  or  to  a  mixture  of 
metals  composed  of  gold  and  silver 

Electrum,  argentiferous  gold;  an  alloy 
of  silver 

Elegance,  in  a  design,  is  a  manner 
which  embellishes  and  heightens 
objects,  either  as  to  their  form  or 
colour,  or  both,  without  destroying 
or  perverting  truth 

Elementary  Instruction.  Before  en- 
tering into  practice,  it  will  be  ne- 
cessary to  bear  the  following  rules 
and  tables  always  in  mind;  and 
although  we  are  to  suppose  every 
one  already  weU  acquainted  with 


167 


ELE 


ELEMENTARY  INSTRUCTION. 


ELE 


them,  they  may  yet  possibly  be 
found  useflil  and  essential  here. 

,  SIGNS  AND  MARKS. 

+  Plus,  or  more :  the  sign  of  ad- 
dition; as  5  +  6»lI 

—  Minus,  or  less :  the  sign  of  sub- 
traction, as  20 — 5  —  1 5 

X  Multiply  by  :  the  sign  of  multi- 
plication, as  8  X  9  ==  72 

+  Divide  by :  the  sign  of  division, 
as  16-f-4»4 

=  Equal  to :  the  sign  of  equality, 
as  27  cubic  feet » 1  cubic  yard 

: :  Proportion :  the  sign  of  propor- 
tion, as  3  :  6  : :  8  :  16 

fl  Fraction 

V  Square  root.     V  Cube  root 

LINEAL  MEASORB. 

7*92  inches     ....     I  link 
12  inches     ....     1  foot 

3  feet 1  yard 

5|  yards .     1  rod,  pole,  or  perch 

4  poles,  100  links    .     1  chain 
40  poles,  10  chains    .     1  furlong 

8  furlongs,  1760  yards,  1  mile 
80  chains,  8000  links     1  mile 

SQUARE  OR  SUPERFICIAL  MEASURE. 

1  square  foot 
1  square  yard 
1  square  pole 

or  perch 
1  rood 
1  acre 
1  square  mile 


144  square  inches 
9  square  feet . 

30^  square  yards  \ 


40  perches 
4  roods 
640  acres . 


CUBIC  OR  SOLID  MEASURE. 

1728  solid  inches    .    1  cubic  foot 
27  solid  feet   .    .    1  cubic  yard 

Proceeding  to  the  various  forms 
of  plane  surfaces,  and  the  methods 
of  measuring  them,  and  beginning 
with  the  square,  which  has  four 


equal  sides  and  four  right  angles, 
as  A,  B,  c,  D, — Rule :  Multiply  the 
given  side  by  itself,  and  the  product 
is  the  area  required.  Ex.  12  x  12 
«144. 

The  next  figure  will  be  a  paral- 
lelogram, or  oblong  square.  Rule  : 
Multiply  the  length  by  the  breadth, 


and  the  product  gives  tbe  area. 
Ex.  18'0^'x6'0"  =  108'0". 

The  next  figure  will  be  a  rhom- 
bus, which  has  four  sides  all  equal, 
but  no  right  angle.    Rule :  Multi- 


ply the  base  by  the  perpendicular 
height,  and  the  product  is  the  area. 
Ex.  16'0"xl4'0"  =  224'0". 

The  next  figure  will  be  the 
rhomboid,  which  has  its  two  sides 
equal  and  parallel,  but  no  right 
angle:  it  is  a  long  square  pushed 


/ 


A 


la'.o' 


h 


aside.  Rule :  Multiply  the  longer 
side  by  the  perpendicular  height 
or  breadth,  and  the  product  is  the 
area.    Ex.l8'0"x  5'6*=99'0". 

The  next  will  be  a  right-angled 
triangle,  having  one  of  its  angles  a 
true  square,  or  just  90  degrees. 


168 


ELE 


ELEMENTARY  INSTRUCTION. 


EL£ 


Rule:  Multiply  one  of  the  legs 
forming  the  right  angle  by  hidf 
the  other ;  the  prodact  is  the  area. 
Ex.  16'  O"-4-2=8'x20'  (T-ieO' 

The  next  figure  wiU  be  a  tri- 
angle.  Rule:  Multiply  the  longest 
side  by  one-half  the  perpendicular, 


and  the  product  it  the  content. 
Ex.  14'  0''-*-2=-7' 0"x24'0"  = 
168'  0",  area  required. 

The  next  figure  will  be  the  tra- 
pezium, whicb  consists  of  four  un- 
equal sides  and  four  unequal  an- 
gles; it  is,  indeed,  two  triangles, 
and  may  be  measured  at  twice,  as 
shown  in  the  preceding  triangle,  or 


by  this  Rale :  Multiply  the  diagonal 
by  one-half  the  sum  of  the  two 
perpendiculars.  Ex.  8'  0*'  +  4'  0" 
=  12'  0"  +  2  =  6'  0"  X  2^  0^« 
120'  0",  the  area  required. 

The  next  figure  will  be  the  area 
of  a  circle.  Rule :  Square  the 
diameter,  and  multiply  that  pro- 
duct by  '7854,  a  decimal,  and  that 


product  will  be  the  oontent.  Ex. 
12'  0"  X  12'e"«144'  (T  X  -7854  = 
1130976. 

The  next  dia- 
gram will  be  a 
segment  orpast 
of  asectiencfa^ 
circle:  to  mea- 
sure this,  mul- 
tiply half  the 
sum  of  the  two 
arches  by  one 
of  the  ends,  and 
the  product  will 
give  the  area. 
Ex.  24'  (T  + 
18'  0''=42'  0" 
+2=21' a"x 
2'  0"  =  42'  0", 
which  is  the 
area  required. 

Where  the  figure  is  found  of 
the  shape  annexed,  with  two  right 
angles,  and  the  sides  not  parallel, 


instead  of  dividing  it  and  measuring 
it  as  a  parallelogram  and  an  angle, 
take  the  mean  of  the  two  per- 
pendiculars, and  multiply  by  the 
length ;  the  product  will  give  the 
area  reqmred.  Ex.  12'  0"  +  8'  0" 
«20'  0"-s-2  =  10'  0"=  X  32'  0"= 
320'  0". 

It  is  now  necessary  to  take  into 
consideration  the  methods  of  mea- 
suring solid  or  cubic  bodies;  for 
example,  to  begin  with  a  cube,  viz. 
a  solid  bounded  by  six  square  sides, 
similar  to  a  die. 

Rule:  Mul-  ^fr 
tiply  the  side  /i^  \ 
by  itself,  and 
that  product 
by  the  side 
again;  the  last 
product     will 


% 
«• 


i&r: 


•^;>- 


be  the  solid  content.    Ex.  6'  0"  x 
6'  0"  =  36'  0"  X  6'  0"  =  216'  0" 
cubic  feet. 


169 


ELEMENTARY  INSTRUCTION. 


The  next  figure 
is  the  panllelo- 
pipedon,  or  oh- 
langcube.  Rule: 
—  Multiply  the 
breadth  by  the 
depth,  and  that 
product  by  the 
iengtli ;  this  last 
product  will  be 
the  content  of  it. 
Ei.  6'0  "  X  B'  0" 
»48'0"x32'0" 
=  1536'  0"  = 
the  required  con- 
tent of  the  paral- 
lelopipedon.  \_ 

Next  proceed  to 
the  prism,  to  measure 
which,  find  the  area  at  / 
the  end,  multiply  that 
by  the  length,  and  that 
product  19  the  conteut. 
Ek.  The  perpendicular 
height,  6'  0"  +  2  = 
3'0"x  12'  0"  =  36'0'' 
K  32' 0"=  1153'  0", 

The  inclined  plane 
and  wedge  may  be 
meaiured  hy  the  same 
rule  *s  tbe  piism  \  but 
the  readier  way  is  to 
multiply  one -half  of| 
the  thickness  of  the  ^ 
baie  by  its  width,  and  ' 


1i\ 


that  by  the  peipendiculKr  or  length, 
Ei.  3'0"x  ia'0"-45'0''x20'0* 
-  gOC  0"  =  coDtent  of  iDclined 

This  flgnre  will  be  found  ii 
eajth-woA,  paiaing  from  col 

to  embankment. 

Again,  6' 0"  x  15' ff'^W  0"x 
20'  0"-1800'  0",  content  of  tl 

The  next  figure  is  a  square  pyra- 
mid, and  the  one-b*lf  of  whidi  is 
>  vety  prominent  formation  in 
banks,  and  is  measured  by  multi- 


plying the  area  td  the  base  by  one- 
third  the  height  or  length.  Ei. 
6'  0"  X  6'  0"  =  36'  0"  X  6'  0"  = 
216'  0"  content. 

Arriving   now    at  the    Cylinder, 
this   ia   measured  by  multiplying 


tbe  area  of  the  base  or  end  by  tbe 
length.  Ex.  12'  Ii"  x  12'  0"  ■= 
114'0"x  ■7854  =  113-0976  x20'r 
»2260'  0", 

The  cone  is  also  measured  by 
multiplying  the  area  of  the  base  by 
one-third  the  perpendieular  height. 
Ex.  ly  0"  X  12' l)"  =  144' f*" 
■7854-113' 0"x6'r'=753' 


ELI 


EMBANKMENTS. 


EMB 


The  next  figure  is  the  frustrum 
of  a  square  pyramid^  iirhich  also  is 

a  form  peculiar  in 
embankments  and 
cuttings.  Rule : 
To  four  times  the 
area  of  the  mean 
base  add  the  area 
of  each  end,  which 
divide  by  6;  mul- 
tiply  the  product 
by  the  length,  you 
will  find  the  con- 
tents. Ex.  4'0"  + 
6'  0"=10'  0"-^2 
==  5'  0",  the  mean 
height  of  the  base 
or  thickness  will  be 
5'0";  5'0"x5'0" 
=  25'0"x4'0"= 
100'0"+36'0"  = 
136'0"+16'0''=152'0";  152' 0" 
-1-6'  0"  =  25'  Af'  X  20'  0"«506'  8" 
content. 

The   same  rule  applies  to  the 
frustrum  of  a  cone. 
Elizabethan  Ardhitecture,  the  style 
which  prevailed  in  England  at  the 
time  of  Queen  Elizabeth,  and  im- 
mediately subsequent  to  the  Tudor 
style  of  Henry  VIII. 
EUipge :  this  curve  is  one  of  the  conic 
sections,   and  next  in  importance 
to  the  circle  and  the  straight  Une 
ElHpsigf  an  oval  figure  generated  from 
the  section  of  a  cone  by  a  plane 
cutting  both  sides  of  the  cone,  but 
not  parallel  to  the  base,  and  meet- 
ing with  the  base  when  produced 
Elliptic  con^a8»€»t  a  term  given  to 
any  machine  for  describing  ellipses 
Elliptograph,  an  instrument  for  draw- 
ing ellipses 
Elntt  ati  mber-tree,  of  European  growth, 
and  of  which  there  are  five  species : 
mean  size,  44  feet  long,  32  inches 
diameter :  it  is  not  liable  to  split, 
and  bears  the  driving  of  nails,  bolts, 
&c. :  much  used  in  building ;  also 
for  the  keels  of  vessels,  and  for  wet 
foundations. 
Elongation^  the  act  of  lengthening 
Elutriationj  the  separation  of  foul  sub- 
stances from  pure,  by  pulverization 

171 


Ehfon,  (in  Cornish),  a  hard  close- 
grained  stone,  said  to  be  a  bastard 
limestone 

Embankments^  raised  mounds  or  dykes 
to  preserve  the  proper  and  useful 
course  of  rivers,  &c. ;  and  also  for 
forming  a  level  line  of  railway 

Embankments  {some)  executed  on  the 
Continent.  On  the  banks  of  the 
Po,  two  sorts  of  dykes  are  used  to 
prevent  the  river  from  overflowing 
during  the  yrinter,  or  the  flood 
season.  They  are  called  '  in  froldi' 
when  immediately  upon  the  banks 
of  the  river,  and  Mn  golene'  when 
at  any  considerable  distance,  as  it 
is  sometimes  found  advisable  to 
allow  the  river  to  spread  over  a 
large  surface  of  the  adjacent  valley, 
either  for  the  purpose  of  admitting 
it  to  deposit  the  mud  in  suspension, 
or  to  dlow  it  to  lose  its  torrential 
character.  The  maintenance  of 
the  works  of  these  dykes  is  con- 
fided to  the  Government  engineers, 
who  are  under  the  control  of  a 
syndicate  of  the  proprietors  of  the 
property  most  liable  to  be  affected 
by  inundations.  When  the  river 
passes  from  one  state  to  another, 
as  from  Piedmont  to  Modena,  a 
mixed  commission  is  charged  with 
the  joint  superintendence. 

The  Haarlem  lake,  besides  the 
very  remarkable  steam  engines  de- 
scribed by  Mr.  Dempsey,  merits 
observation  for  the  extensive  works 
executed  for  the  defence  of  the 
land,  and  for  the  canals  reserved 
for  the  navigation.  The  enclosure 
dyke  is  50,000  metres  long,  or 
rather  more  than  31  miles.  It  has 
two  outfall  dykes,  which  serve  for 
the  navigation,  9000  metres,  about 
5^  miles;  one-half  of  which  is  40*"* 
(131  ft.  2  in.)  wide  at  the  bottom 
or  floor  line;  the  other  43'°'20 
(141ft.  10  in.) 

The  ordinary  tides  are,  at  the 
flux,  2  ft.  4  in.  above  the  scale  or 
datum  line  at  Amsterdam ;  at  the 
reflux,  2  ft.  8  in.  below  the  same 
datum:  the  difference  between 
high  and  low  water  is  then,  on  the 


EMB 


ENAMELLING. 


ENC 


average,  about  5  feet.  With  vio- 
lent  winds  from  the  n.w.  however, 
the  tides  rise  sometimes  6  ft.  6  in. 
above  the  average.  The  tides  of 
the  Y,  near  the  liJ^e,  are  +  16<^'  (or 
6i  in.)  and  —  23<"  (or  9  in.),  giving 
a  total  variation  of  1  ft.  3^  in. 

The  estimated  cost  of  reclaiming 
the  18,000  hectares  was  8  millious 
of  florins,  or  £667,000  English, 
nearly,  about  JS 13  per  acre.  Pre- 
viously to  undertaking  this  colos- 
sal work,  the  Zind  Plas,  of  4600 
hectares  superficial  (nearly  11,500 
acres),  had  been  reclaimed  at  a  cost 
of  3  millions  of  floiins,or  £ 250,000; 
not  far  from  £  22  per  acre. 

The  heights  of  the  enclosure 
dyke  are  +  or  —  the  datum  line 
at  Amsterdam,  or  the  mean  level  of 
the  sea  in  that  port. 

Embankment  of  the  flooded  part  of 
the  Amsterdam  and  Haarlem  Rail- 
way.— The  bottom  part  consists  of 
treble  ranges  of  fascines,  tied  down 
by  longitudinal  poles  1  metre  apart 
from  centre  to  centre,  and  0*25<:' 
diameter;  two  double  stakes  at 
each  end  of  the  poles,  and  two  ties 
in  the  intennediate  distances.  The 
interstices  of  the  fascines  and  the 
space  between  the  rows  are  filled  in 
with  sand.  The  upper  part,  form- 
ing the  encasement  for  the  ballast, 
is  made  of  three  rows  of  treble  fas- 
cines, well  staked,  and  wattled  to- 
gether. 

A  core  of  sand  or  clay,  faced  with 
step  fascines,  is  made  up  to  low- 
water  mark.  Upon  this  a  bed  of 
rushes,  fastened  down  by  stakes 
and  wattles,  is  laid ;  and  the  upper 
portion  of  the  bank  is  faced  with 
fascines  of  a  regular  slope  of  1  to  1. 

Embattled,  a  term  appUed  to  any 
building  with  a  parapet,  and  having 
embrasures  to  resemble  a  battery 

Emblema,  an  emblem,  or  inlaid  orna- 
ment of  divers  colours 

EmbobUf  in  mechanics,  a  wedge ;  an- 
ciiently,  among  the  Greeks,  the  prow 
or  beak  of  a  vessel,  or  a  body  of 
soldiers  in  the  form  of  a  wedge 

Embo98mg^f  fonning  work  in  reUevo, 


whether  cast  or  cut  with  a  chisel ; 
or  in  modem  times,  the  art  of  ihto- 
ducing  raised  figures  upon  wood  or 
othermaterialsby  means  of  pressure, 
either  applied  by  a  sudden  blow,  as 
in  a  stamping  press,  or  in  a  more 
gradual  manner,  as  by  an  ordinary 
screworhydraulic  press,  orbymeans 
of  revolving  cyUnders 

Embrasure,  the  crenelles  or  intervals 
between  the  merlons  of  a  battlement 

Embroidery,  a  mode  of  working  de- 
vices on  woven  substances 

Emerald  green  is  a  new  colour  of  cop- 
per green  upon  a  terrene  base :  it  is 
the  most  vivid  of  this  tribe  of 
colours,  being  rather  opaque,  and 
powerfully  reflective  of  light:  it 
appears  to  be  the  most  durable  pig- 
ment of  its  class 

Emissarhtm,  a  sluice,  flood-gate,  or 
channelby  which  an  outlet  is  formed 
to  carry  off  stagnant  or  foul  water: 
accordingto  Pliny,  an  artificial  canal 
formed  for  the  draining  of  stagnant 
waters 

Emplecton,  a  method  of  constructiog 
walls  introduced  by  the  Greeks  and 
copied  by  the  Roman  architects,  in 
which  the  outside  surfeu^es  on  both 
sides  were  formed  of  ashlar  laid  in 
regular  courses,  and  the  central 
space  between  them  filled  in  vnth 
rubble-work,  layers  of  cross  stones 
being  placed  at  intervals  in  regular 
courses,  and  of  sufiicient  size  to  ex- 
tend through  the  entire  thickness 
of  the  wall  from  side  to  side,  and 
so  act  as  girders  to  bind  the  whole 
together 

Emporium,  a  mart  or  factory,  a  large 
building  containing  ranges  oft)ond- 
ing  warehouses,  in  which  foreign 
merchandise  brought  by  sea  is  de- 
posited for  sale 

EnamelUng,  the  art  of  using  enamel, 
which  is  divided  into  transparent 
and  opaque.  The  first  is  employed 
for  the  purpose  of  ornamenting  gold 
and  silver;  the  second,  commonly 
in  the  manufacture  of  watch  and 
clock  dials,  and  of  plates  for  pic- 
tures, &c. 

Enearpa,  according  to  Vitravius,  fes- 


172 


ENC 


ENGINEERING,  CIVIL. 


ENG 


toons  of  carved  fruit  and  flowers, 

employed  as  decoratiye  ornaments 

Encafjms,  a  festoon  of  fruit,  flowers, 

&c.,  used  as  ornaments  on  frieses 
Encau»tieaf  the  art  of  encaustic  paint- 
ing, t.  e.  in  colours  mixed  with  wax, 
and  afterwards  hardened  by  the  ac- 
tion of  Are 
Encaustic  palntmff^  a  kind  of  painting 
in  which,  by  heating  or  burning  in, 
the  colours  are  rendered  permanent 
in  all  their  original  splendour 
Enchasing,  the  art  of  enriching  and 
beautifying  gold,  silver,  and  other 
metal  work,    by  some  design  or 
figure  represented  thereon  in  low 
relievo 
EncUmare,  a  fence,  a  wall,  or  hedge,  or 
other  means  of  protection  and  se- 
curity surrounding  land 
EndecagoHf  in  geometry,  a  plane  figure 

of  eleven  sides  and  angles 
End-iron*,  andirons  or  dogs,  articles 
of  household  furniture  in  eariier 
times,  used  in  fire-places  to  sustain 
the  ends  of  logs  of  wood 
Engineerinff,  CiviL  This  profession 
may  be  said  to  have  originated  in 
England  about  the  middle  of  the 
last  century.  Before  that  period, 
whenever  the  prospects  of  great 
profit  induced  individuals  or  bodies 
to  incorporate  themselves  for  the 
purpose  of  undertaking  extensive 
systems  of  drainage,  or  for  the 
supply  of  water,  requiring  the  as- 
sistance of  an  engineer,  recourse 
was  generally  had  to  those  great 
masters  of  hydraulic  engineering, 
the  Dutch.  True  it  is  that  some  so- 
litary exceptions  have  occasionally 
been  found;  men  who,like  Sir  Hugh 
Myddelton,  combined  a  speculative 
turn  of  mind  vrith  some  mechanical 
knowledge,  and  to  these  two  quali- 
ties  added  an  untiring  energy  of  pur- 
pose, leading  them  to  persevere  in 
any  undertaking,  even  under  the 
most  cUseouraging  drcumstanees. 
But  these  men  were  rare  instances 
of  a  peculiar  talent,  which,  though 
it  thus  displayed  itself  occasionally, 
was  far  too  uncommon  a  gift  to 
allow  the  possessors  of  it  to  form  a 


class  or  profession.  The  case  is  very 
different  now:  a  demand  for  this 
peculiar  talent  has  been  created  of 
late  years  by  the  extraordinary  de- 
velopment of  our  system  of  internal 
communication,  as  well  as  by  the 
application  of  steam  to  the  purposes 
of  our  manufiictures ;  and  employ- 
ment is  now  found  for  hundreds 
where  one  was  sufficient,  not  fifty 
years  since,  for  the  whole  business  of 
the  country.  So  great  indeed  has 
been  the  demand,  that  the  pn^es- 
sion  may  be  said  to  be  divided  into 
two  distinct  bodies,  viz.  those  who 
turn  their  attention  to  subjects 
which  come  moreparticularly  within 
the  scope  of  the  duty  of  a  civil  en- 
gineer, such  as  docks,  bridges, 
canals,  railroads,  &c.,  and  those 
who  devote  themselves  altogether 
to  the  manufacture  of  machinery. 
The  duties  which  are  involved  in 
the  practice  of  these  two  branches 
of  the  profession,  though  apparently 
dissimilar  in  character,  are  yet 
founded  upon  the  same  general 
principles;  and  the  acquirements 
which  are  necessary  to  enable  the 
individual  of  one  dass  to  distin- 
guish himself,  or  even  to  practise 
his  profession  with  a  moderate 
chance  of  success,  will  be  found 
equally  necessary  for  those  of  the 
other  class. 

These  acquirements  are  partly 
abstract  and  theoretical,  and  partly 
experimental  or  practical.  A  civil 
engineer  should,  in  addition  to  the 
knowledge  required  to  fit  him  as 
well  as  others  for  the  active  duties  of 
Ufe,  have  such  a  knowledge  of  ma- 
thematics as  will  enable  him  to  in- 
vestigate as  well  as  to  apply  the 
rules  laid  down  by  writers  on  those 
branches  of  the  mixed  sciences  to 
which  his  attention  will  roost  fre- 
quently be  drawn.  He  should  be 
well  acquainted  with  the  principles 
of  mechanics,hydrBulics,and  indeed 
with  all  the  branches  of  natural 
philosophy;  and  a  certain  amount  of 
chemical  knowledge  will  be  found 
very  valuable :  he  should  be  able  to 


173 


ENG 


ENGINEER,  STEAM-BOAT. 


ENG 


draw  neatly,  and  should  understand 
the  principles  of  projection  upon 
which  all  engineering  drawings  are 
constructed:  a  general  knowledge 
of  the  principles  of  architecture  will 
also  he  essential.  Having  acquired 
the  requisite  amount  of  theoretical 
information^  the  next  step  is  to  gain 
that  practical  knowledge  which  is 
essential  in  order  to  the  proper  ap- 
plication of  this  information.  The 
hest  mode  of  gaining  this  experience 
is  to  enter  into  the  employment  of 
some  eminent  man  in  the  profession, 
in  whose  office  there  will  be  every 
opportunity  offered  to  the  young 
beginner  of  witnessing  the  mode  in 
which  the  various  descriptions  of 
work  are  carried  on.  He  will  there 
be  employed,  first  as  a  draughtsman, 
in  copying  drawings :  as  he  becomes 
more  acquainted  with  practical  de- 
tails, he  will  have  more  responsi- 
bility thrown  upon  him,  and  be 
placed  in  charge  of  works,  at  first 
of  small  importance, but, by  degrees, 
of  those  of  such  magnitude  as  will 
require  all  his  theoretical  know- 
ledge, and  all  the  practical  expe- 
rience he  may  have  gained,  to  enable 
him  to  carry  out  the  work  to  the 
satisfaction  of  his  employers:  he 
should  cultivate  a  habit  of  observa- 
tion, and  make  a  point  of  taking 
ample  notes  and  sketches  of  what- 
ever  he  may  see  which  in  any  way 
bears  upon  his  profession.  Having 
thus  by  degrees  acquired  a  sufficient 
amount  of  information  to  give  him 
a  confidence  in  his  own  judgment 
upon  any  subject  which  may  be 
submitted  to  him,  and  having  be- 
come known  as  an  active  and  intel- 
ligent agent  of  others,  he  will  very 
possibly  be  called  upon  to  plan  and 
execute  a  work  himself,  and  then, 
by  degrees,  with  industry  and  ac- 
tivity, may  work  his  way  upwards 
in  a  profession  where  merit  alone 
can  lead  to  distinction. 

The  course  of  the  man  who  de- 
votes himself  to  the  machinery 
branch  of  the  profession  differs  but 
little,  up  to  a  certain  point,  from 

174 


that  just  described :  his  theoretical 
acquirements  should  be  the  same, 
but  the  practical  part  of  his  edu- 
cation will  commence  at  the  bench, 
where  he  will  learn  the  use  of  all 
the  tools  and  machinery  by  working 
at  them  vrith  his  own  hands:  he 
will  then  be  placed  in  the  dravring 
room,  and  go  through  much  the 
same  routineof  instruction  as  before 
described,  and  will  by  degrees  work 
his  way  up  to  the  position  of  fore- 
man ;  then,  distinguishing  himself 
by  a  power  of  applying  general  prin- 
ciples to  particular  cases,  he  will 
show  himself  capable  of  assuming 
the  direction  of  an  establishment 
for  the  manufacture  of  machinery. 
Engineer^  Steam-boat,  A  steam-boat 
engineer  is  a  person  employed  for 
the  purpose  of  keeping  the  engine 
or  engines  of  a  steam  vessel  in  as 
efficient  a  state  as  possible,  and  to 
superintend  their  working. 

He  must  set  the  engines  to  work, 
regulate  their  speed,  and  stop  them 
as  may  be  required.  His  duties 
while  the  engines  are  at  work  are 
various.  He  must  take  care  that 
every  moving  part  is  properly  lu- 
bricated ;  that  no  steam  is  allowed 
to  pass  through  valves  or  joints  that 
ought  to  be  steam-tight;  that  no 
air  is  permitted  to  enter  into  any  of 
the  parts  of  the  engine  where  it  is 
essential  that  a  vacuum  should  be 
kept  up ;  and  that  none  of  the  bolts, 
or  pins,  or  keys,  work  loose  by  the 
vibration,  and  shift  their  position, 
or  come  out  of  their  places.  He 
must  also  take  care  that  none  of  the 
working  parts  become  overheated 
by  any  undue  amount  of  friction, 
arising  from  any  want  of  proper  lu- 
brication, any  excessive  tightness,  or 
any  other  disturbing  cause  $  and  if 
they  should  become  overheated,  he 
must  take  prompt  and  energetic 
measures  to  remedy  the  evil,  and 
prevent  any  serious  consequences 
arising  therefrom.  He  must  from 
time  to  time  carefully  observe  the 
effect  produced  by  the  gradual  wear 
of  the  working  pai*ts,  so  that  if  the 


ENG 


ENGINEER,  STEAM-BOAT. 


ENG 


truth  or  accuracy  of  any  of  these 
seems  to  be  materially  affected,  he 
may  take  steps  to  rectify  the  defects 
when  lying  up  in  harhour.  He  must 
also  be  careful  to  observe  if  the 
frame  of  the  engine  ever  begins  to 
move  or  work  in  any  way,  and  en- 
deaTOur  to  discover  the  cause,  in 
order  that  it  may  be  remedied  when 
the  engines  are  at  rest.  One  of  the 
most  important  of  his  duties  is  to 
take  care  that  the  engines  are  kept 
dean,  and  any  grit  or  dirt  prevented 
from  getting  into  the  bearings  or 
moving  parts :  he  must  wipe  away 
all  oil  and  grease  most  carefully 
and  completely  as  soon  as  they  have 
passed  through  the  bearings,  and 
prevent  them  from  running  down 
the  rods  or  renudning  about  the 
engine. 

The  boiler  requires  his  unremit- 
ting and  particular  attention,  in 
order  that  the  proper  supply  of 
steam,  neither  too  much  nor  too 
little,  may  be  generated  for  the  en- 
gine. To  insure  this,  the  manage- 
tneiit  of  the  fires  must  be  duly  at- 
tended  to,  both  in  the  supply  of  coal 
in  the  proper  quantities  at  the  pro- 
per intervals,  and  in  the  periodical 
clearing  of  the  fires  from  the  earthy 
matters  of  the  coal,  which  may  have 
become  vitrified  in  the  furnace,  and 
formed  what  are  called  clinkers. 
By  due  attention  to  the  former,  the 
smoke  in  all  well-proportioned  boil- 
ers maybe  very  greatly  abated;  and, 
by  due  attention  to  both,  the  con- 
sumption of  fuel  (when  the  engines 
are  prevented  by  a  strong  head 
wind,  or  by  the  deep  immersion  of 
thepaddie-wheelsonthecommence- 
ment  of  a  long  voyage,  from  making 
the  proper  number  of  strokes,  and 
thus  using  the  proper  amount  of 
steam,)  may  be  reduced  in  an  equal 
or  greater  degree  than  has  taken 
place  in  the  consumption  of  steam. 
The  due  and  constant  supply  of 
water  to  the  boiler,  to  compensate 
for  the  constant  evaporation  of  the 
water  in  the  formation  of  the  steam, 
must  be  assiduously  attended  to. 


Another  of  the  most  important  of 
the  duties  of  a  steam-boat  engineer, 
during  the  time  that  the  engines 
are  at  work  on  a  voyage  at  sea, 
is  to  attend  to  the  degree  to  which 
the  water  in  the  boilers  may  be- 
come saturated  with  salt  by  the  con- 
tinued evaporation  which  is  going 
on,  and  to  take  care  that  this  satu- 
ration is  not  allowed  to  be  carried 
to  such  an  extent  as  that  a  deposi- 
tion of  the  salt  and  other  matters 
contained  in  sea-water  should  take 
place.  After  the  boilers  have  been 
in  operation  for  three  or  four  hours 
in  salt  water,  so  that  the  water  in 
them  has  become  brine,  he  ought  to 
test  the  strength  of  it,  that  is,  he 
ought  to  ascertain  the  degree  of  sa- 
turation to  which  it  has  reached, 
and  continue  this  examination  pe- 
riodically, whether  the  engines  are 
fitted  with  an  apparatus  for  the  con- 
tinuous discharge  of  a  poi*tion  of 
the  brine,  to  be  exchanged  for  a 
portion  of  sea-water,or  whether  this 
system  of  exchange  is  left  entirely 
at  his  discretion,  to  be  attended  to 
by  means  of  the  common  blow-off 
cocks.  The  best  test  is  the  common 
hydrometer,  though  the  thermome- 
ter has  hitherto  been  more  com- 
monly applied  to  this  purpose,  as 
the  brine  is  considered  to  be  of  a 
proper  strength  when  it  boils  under 
atmospheric  pressure  at  a  tempera- 
ture 2°  higher  than  that  at  which 
the  common  sea-water  will  boil  at 
the  same  time,  under  the  same  cir- 
cumstances. 

Before  coming  into  port,  it  may 
occasionally  beadvantageous  to  take 
indicator  diagrams,  to  see  whether 
the  action  of  the  valves  continues 
to  be  correct. 

The  duties  of  a  steam-boat  en- 
•  gineer,  on  arriving  In  port  after  a 
long  voyage,  are  also  various,  and 
equally  important  with  those  he  has 
to  perform  when  out  at  sea.  Im- 
mediately on  coming  to  anchor,  it 
is  a  good  practice  to  test  the  tight- 
ness of  the  steam-valves  and  pistons, 
by  patting  them  in  such  a  position 


175 


BNO 


ENGINEER. 


ENG 


that  it  can  be  seen  if  they  allow  any 
ateam  to  pass  when  it  ought  not  to 
do  so.  II  any  imperfections  in  these 
the  most  yiUl  parts  of  the  engines 
are  discovered,  he  muttdnwout  the 
Talves^or  Uft  the  cyUnder  covers,,  to 
get  at  the  pistons^  and  rectify  the 
defects  in  the  best  manner  that  he 
can  with  the  means  mthin  his 
power.  He  should  also  occasionally 
examine  all  the  interior  parts  of  the 
engines,  and  rectify  any  incipient 
defectSk  lie  must  now  also  rectify 
any  want  of  truth  in  tfaeparallel  mo- 
tion or  in  any  of  the  shafts  or  work- 
ing parts  caused  by  wear,and  tighten 
or  make  good  any  of  the  fastenings 
of  the  frame  if  be  has  found  them 
to  be  loose,  and  put  to  rights  any 
other  such  defecta.  Any  parts  sub- 
ject to  corrosion  should  be  carefully 
examined,  cleaned,  and  dried,  and 
painted  if  need  be.  The  water 
should  be  blown  eff  ovt  of  the 
boilieia  ae  completely  as  possible, 
and  all  ashes  and  soot  thoroughly 
cleaned  out  of  the  furnaces  and 
flues  as  soon  as  possible.  The  fur- 
naces and  flues  must  then  be  tho- 
loughly  examined,  and  the  shghtest 
teak  ordkfeet  thai  can  be  discovered 
made  good ;:  aa  it  ia  especially  im- 
portant in  a  boiler  to  stop  these 
defects  at  the  first,  as  otherwise 
they  qpread  very  rapidly.  No  pains 
should  be  spwed  to-discover  any  sus- 
pected leak  of  steam  on  the  te^  of 
theboUer,  as  nothing  tends  more  to 
corrode-  and  destroy  a-  boiler  than 
this.  Inside  the  boilers,  any  scale 
that  may  have  been  deposited  from 
the  brine  having  been  allowed  to  be* 
come  too  strong  must  be  removed, 
and  the  whole  thoroughly  cleaned 
out  from  every  part  of  ^e  boiler, 
from  below  as  well  as  from  the  tops 
and  sides  of  the  furnaces  and  flues. 
The  'take^^up,  the  inside-of  the  steam- 
chests>juidi>f  theroofiMf  theboUars, 
wlHck  aie  the  parta  most  subjeot  ta 
corrosion  from  the  interior,,  should! 
be  very  carefully  examined,  and 
after  being  duly  scraped  and  cleaned 
and   dried,  they  should  be  well 

"176  " 


painted  with  two  or  three  coata  of 
led  lead,  or  done  over  with  aome 
other  preservative. 

The  paddle-wheels  should  a]s»  be 
thoroughly  examined,,  and  any  bro- 
ken flbata  or  hook-bolts  replaced  by 
new  ones.  The  whole  of  the  iron- 
work should  be  thoroughly  scraped 
and  cleaned,  and,  when  dry,  painted 
with  three  coats  of  red  lead,  or 
done  over  with  black  varnish,,  once 
every  four  months  at  least.  When 
in  harbour,  especially  if  lying  in  a 
stream  or  tideway ,.the  wheels  ought 
to  be  turned  round  every  three  or 
four  days,  to  change  the  parts  ex- 
posed to  the  action  of  the  vrater,  and 
thus  prevent  corrosion. 

He  must  now  also  get  his  supply 
of  st(Hres  made  good,  so  as  to  be 
ready  for  another  voyage. 

To  qualify  an  engineer  to  per- 
form these  duties,  he  should  be 
trained  as  a  mechanic,  and  be  a  fair 
workman  in  iron,  brass,  and  wood. 
He  should  be  able  to  work  not  only 
at  the  lathe  or  vice,  but  also  at  a 
smith's  forge.  His  education  should 
be  such  as  to  make  him  able  to  keep 
accounts,  and  make  notes  in  his  log 
of  all  that  occurs  in  the  engine- 
room.  He  should  have  sufficient 
knowledge  of  mechanical  drawing 
to  enable  him,  in  the  event  of  any 
important  part  of  the  engines  being 
broken  when  at  a  distance  from  any 
manufactory,  to  make  such  advavr- 
ing  of  it  as  would  enable  a  manu- 
facturer to  replace  it.  He  should 
have  some  knowledge  of  the  first 
principles  of  mechanics,  a  gararal 
knowledge  of  the  leading  principles 
of  hydrostatics,  hydraulics,  and 
pneumatics,  without  which  he  can- 
not fully  understand  many  of  the 
principles  carried  on  in  the  engine, 
and  on  which  its  power  dependa. 
Some  knowledge  of  heat,  of  the 
tiieory  of  oomba8tion,.of  ebullition, 
and  of  evaporation^  may  also  be- 
leckoned  aa  almost  indiapensahliat 
to  which  should  be  added,  ii  pea- 
aihle,  an  acquaintance  with  the  sub- 
ject of  steam,  especially  as  regarda 


ENG 


ENGINEER,  MECHANICAL. 


EPI 


its  temperature,  pressnre,  and  latent 
heat. 

Engineer^  Meehanical,  one  who  is  effi- 
cient in  the  invention,  contitrance, 
patting  together,  andthe  adjustment 
of  all  kinds  of  machinery';  who  is 
moqnainted  with  the  strength  and 
qualityof  the  material  used,  and  who 
also  x^ossesses  a  thorough  knowledge 
of  the  power  of  steam  andthe  engine 
in  all  its  modifications,  andthe  uses 
for  which  this  motive  power  is  ap- 
plied :  he  should  also  he  duly  ac- 
quainted with  mill-work  of  the 
several  kinds,  whether  impelled  hy 
«team,  water,  or  wind. 

English  Schoai  of  Painting.  This 
school,  which  is  hut  of  recent  date, 
is  connected  with  the  Royal  Aca- 
<^emy  in  London,  instituted  in  1 766 ; 
and  although  as  a  school  it  did  not 
exist  hefore  that  period,  yet  since 
the  revival  of  the  arts,  and  the  con- 
sequent encoturagement  given  to 
them  hy  the  sovereigns  of  Europe, 
England  has  possessed  portrait - 
painters  of  no  inconsiderable  ability; 
and  it  is  probably  ovdng  to  the  re- 
markahle  partiality  of  the  nation 
for  this  hranch  of  the  art,  that 
historical  painting  has  been,  until 
recently,  comparatively  neglected. 
Latterly,  however,  painters  of  the 
highest  eminence  in  this  superior 
branch  of  the  art  have  distinguished 
themselves,  and  given  earnest  of  the 
rise  of  a  school  that  may,  ere  long, 
surpass  others  of  the  present  age. 

Entablature,  those  members  of  a  por- 
tico which  were  constructed  upon 
the  columns,  consisting  of  the  epi- 
stylium,  zophorus,  and  corona.   Vi- 
truvius  uses  the  words  amamenta 
eohinmarum  to  signify  these  mem- 
bers;  and  sometimes  he  includes 
the  three  several  parts  in  the  term 
epistyHa. 
Entablature,  the  superstructure  that 
lies  .hori2sontally  upon  the  columns 
in  the  several  orders  or  styles  of 
architecture.     It  is  divided  into 
archi^nve,  the  part  immediately 
above  the  column ;  fneze,  the  cen- 
tral space ;  and  cornice,  the  upper 

177  hT 


projecting  mouldings.  Each  of  the 
orders  has  its  appropriate  entabla* 
ture,  of  which  both  the  general 
heightandthe  subdivisions  are  regu- 
lat^by  a  scale  of  proportionderived 
from  the  diameter  of  the  column. 

Entablatures,  and  their  mtbdMrion, 
The  entablature,  though  architects 
frequently  vary  fromthe  proportions 
here  specified,  may,  as  a  general 
rule,  be  set  up  one-fourth  the  height 
of  the  column.  The  total  height 
thereof  thus  obtained  is  in  all  the 
orders,  except  the  Doric,  divided 
into  ten  parts,  three  of  which  are 
given  to  the  architrave,  three  to  the 
frieze,  and  four  to  the  cornice.  But 
in  the  Doric  order  the  whole  height 
should  be  divided  into  eight  parts, 
and  two  given  to  the  architrave, 
three  to  the  frieze,  and  three  to  the 
cornice.  The  mouldings  which  form 
the  detail  of  these  leading  features 
are  best  learned  by  reference  to  re- 
presentations of  the  orders  at  large. 
Palladio  and  Vignola,  the  restorers 
of  genuine  architecture,  are  the 
authors  whose  works  may  be  con- 
sulted with  greatest  advantage  by 
those  who  desire  to  make  any 
advance  in  the  science,  and  most 
particularly  by  those  who  vrish  to 
obtain  further  knowledge  on  the 
use  and  abuse  of  its  details. 

Entail,  a  term  used  in  the  middle  ages 
to  signify  elaborated  sculptured  or- 
naments and  carvings 

Entasis,  the  swell  of  the  shaft  or  co- 
lumns of  either  of  the  orders  of  ar- 
chitecture 

Enterclose,  a  passage  between  two 
rooms  in  a  house,  or  that  leading 
from  the  door  to  the  hall 

Entresol,  in  architecture,  a  fioor  be- 
tween two  other  floors.  The  en- 
tresol consists  of  a  low  apartment 
usually  placed  above  the  first  fioor: 
in  London,  frequently  between  the 
ground  fioor  and  the  first  floor. 

Ephebeum,  an  apartment  in  the  pa- 
lasstra  appropriated  to  wrestling 
and  other  atldetic  exercises 

Epieyele,  a  little  circle  whose  centre 
is  in  the  circumfieMnce  of  a  greater  I 


EPI 


EVOLUTION. 


EVO 


Epicycloid^  a  curve  generated  by  the 
revolution  of  the  periphery  of  a 
circle  along  the  convex  or  concave 
part  of  another  circle 

Epicycloidal  wheel,  a  v?heel  for  con- 
.  verting  circular  into  alternate  mo- 
tion, or  alternate  into  circular 

£^i8cenium,  a  division  of  the  scene  of 
a  Greek  theatre :  it  sometimes  con- 
sisted of  three  divisions  made  by 
ranges  of  columns  one  above  the 
other:  the  lovrer  was  termed  seenaf 
and  the  others  episcenia 

Epistomium,  the  cock  or  spout  of  a 
v^ater-pipe,  or  of  any  vessel  contain- 
ing liquids  to  be  drawn  off  in  small 
quantities  when  required 

JJ^natyUumfthe  lowerof  three  divisions 
of  an  entablature  or  superstructure 
upon  the  columns  of  a  portico, 
formed  by  pieces  etxending  from 
centre  to  centre  of  two  columns 

J^nityliumf  the  architrave  or  hori- 
zontal course  resting  immediately 
upon  columns.  I^tisiylar  arcuation 
is  the  system  in  which  columns  sup- 
port  arches  instead  of  horizontal 
architraves  and  entablatures. 

EpitithidoBf  a  term  applied  by  some 
writers,  by  way  of  distinction,  to  the 
cjrmatium  on  the  sloping  or  raking 
cornices  of  a  pediment,  which  su- 
perimposed moulding  (as  its  name 
implies)  was  frequently  largely  de- 
veloped, and  enriched  with  an  or- 
namental pattern 

Epitit hides,  the  upper  members  of  the 
corona  surmounting  the  fastigium 
of  a  temple,  which  was  also  con- 
tinued along  the  flanks 

Equation^  an  equal  division :  in  alge- 
bra, a  mutual  comparing  of  things 
of  different  denominations:  in  as- 
tronomy, the  difference  between  the 
apparent  and  mean  motion  of  the  sun 

Equilateralf  having  all  sides  equal 

Equilibrium,  equipoise,  equality  of 
weight 

EquHtbrium  valve,  the  valve  in  the 
steam  passage  of  a  Cornish  engine 
for  opening  the  communication  be- 
tween the  top  and  bottom  of  the 
cylinder,  to  render  the  pressure 
equal  on  both  sides  of  the  piston 

178 


Era,  The  year  5611  of  the  Jewish 
era  commences  September  7, 1850 ; 
Ramad&n,  the  month  of  abstinence 
observedby  the  Turks,  July  11,1850 ; 
the  year  1267  of  the  Mohammedan 
era,  Nov.  6,1850 ;  and  the  Christian 
era,  1849  since  the  birth  of  Jesus 
Christ,  for  1850  years,  on  the  1st 
of  January,  1850. 

Ergastulum,  a  sort  of  prison  or  house 
of  correction  contiguous  to  the  farms 
and  country  villas  of  the  Ronums 

Ergaia,  a  capstan  or  vnndlass 

Ermine,  in  heraldry,  a  white  field  or 
fur,  powdered  and  interspersed  with 
black  spots,  resembling  the  skin  of 
an  animal  so  named 

Escape,  the  scape  of  a  column  in  ar- 
chitecture 

Escutcheon,  a  shield  charged  with 
armorial  bearings 

Etching,  a  branch  of  engraving  in 
which  the  lines  are  drawn  by  a 
stylus  or  etching-needle,  on  copper, 
steel,  or  stone,  prepared  by  a  che- 
micd  process 

Eudiometer,  an  instrument  used  to 
ascertain  the  purity  of  air,  or  rather 
the  quantity  of  oxygen  contained 
in  any  given  bulk  of  elastic  fluid 

Euripus,  any  artificial  canal  or  water- 
course,  of  greater  or  lesser  extent, 
such  as  were  made,  according  to 
Pliny,  to  ornament  a  Roman  i^a ; 
also  an  arm  of  the  sea 

Eustyle,  that  intercolumniation  which, 
as  its  name  would  import,  the  an- 
cients considered  the  most  elegant,  • 
viz.  two  diameters  and  a  quarter  of 
the  column.  Vitruvius  says,  this 
manner  of  arranging  columns  ex- 
ceeds all  others  in  strength,  con- 
venience, and  beauty 

Evaporation,  the  transformation  of  a 
liquid  into  a  gaseous  state  by  the 
action  of  heat 

Evolute,  a  particular  species  of  curve 

Evolution,  in  geometiy:  the  equable 
evolution  of  the  periphery  of  a 
circle,  or  any  other  curve,  is  such 
a  gradual  approach  of  the  drcum- 
ference  to  rectitude  as  that  all  the 
parts  meet  together,  and  equally 
evolve  or  unbend 


EXA 


EXPANSIVE  STEAM. 


EXP 


Ewry,  an  office  of  household  service, 
where  the  ewers,  &c.,  were  formerly 
kept 

Examen,  the  tongue  on  the  beam  of  a 
balance,  rising  perpeudicularlyfrom 
the  beam,  and  moving  in  an  eye 
affixed  to  the  same,  by  which  it 
serves  to  point  out  the  equality  or 
inequality  of  weight  between  the 
objects  in  the  scale 

Exedra,  an  assembly-room  or  hall  of 
conversation ;  'according  to  Vitru- 
vius,  a  large  and  handsome  apart- 
ment ;  also  a  by-place,  or  jutty 

Exedra,  or  JBjphedra,  the  portico  of  the 
Grecian  palaestra,  in  which  dispu- 
tations of  the  learned  were  hdd : 
so  called  from  its  containing  a  num. 
ber  of  seats,  generally  open,  like  the 
pastas  or  vestibule  of  a  Greek  house 

Exemplar^  a  pattern,  plan,  or  model ; 
resemblance 

Exhausi'part,  the  exit  passage  for  the 
steam  from  a  cylinder 

Exhauat'Vdbfet  the  valve  in  the  educ- 
tion passage  of  the  steam  cyUnder 
of  a  Cornish  engine,  placed  between 
the  cylinder  and  air-pump,  and 
worked  by  the  tappet  motion,  so  as 
to  open  shortly  after  the  eqnili- 
brium  -valve,  and  admit  the  steam 
to  the  condenser 

Expantion  joint,  a  stuffing-box  joint 
connecting  the  steam  pipes,  so  as 
to  allow  one  of  them  to  slide 
within  the  enlarged  end  of  the 
other  when  the  length  increases 
by  expansion 

Expansion  valve,  an  auxiliary  valve 
placed  between  the  slide-valve  and 
the  steam  cylinder:  it  is  worked 
by  a  cam  or  other  contrivance,  so 
as  to  cut  off  the  steam  at  a  given 
period,  and  cause  the  remainder  of 
the  stroke  to  be  performed  by  ex- 
pansion 

Expansive  steam.  The  expansive  pro- 
perties of  steam  are  nowwell  under- 
stood, and  extensively  applied  to 
practice  in  manufacturing  districts. 
In  Comvnill,  and  in  some  other 
parts  of  thekingdom,the  application 
is  attended  with  ^ghly  beneficial 
results*     But  it  should  be  stated 

179 


that  this  system  can  be  introduced 
with  much  greater  advantage  in  en- 
gines that  are  employed  in  raising 
water,  than  in  those  which  are  en- 
tirely devoted  to  manufacturingpur- 
poses.  In  these  last,  the  power  is 
opposed  to  a  continually  varying 
resistance ;  while,  in  the  former,  the 
resistance  is  commonly  the  same, 
or  of  equal  intensity. 

To  pumping  engines,  the  adop- 
tion of  the  expansive  system  to  an 
almost  unlimited  extent  is  recom- 
mended, even  to  the  exclusion  of 
any  further  ingress  of  steam  to  the 
cylinder  after  the  piston  has  passed 
through  but  one-eighth  or  one- 
ninth  of  its  stroke. 

Expansive  steam  may  be  thus 
explained : — If  we  allow  steam  to 
flow  into  the  cylinder  of  a  steam 
engine  until  the  piston  be  de- 
pressed to  one-half  of  the  stroke, 
and  then  prevent  the  admission  of 
any  further  quantity,  ihe  piston 
will,  if  the  engine  be  properly 
weighted,  continue  its  motion  to 
the  bottom.  The  pitssstire'  of  the 
steam,  so  long  as  the.  supply  is 
continued  from  the  boiler,  will 
be  equal,  it  is  presumed,  to  ten 
pounds  upon  the  inch.  '  With  this 
force  it  will  act  upon  the  piston 
until  it  completes  one-half  of  the 
stroke :  the  further  supply  of  steam 
vrill  then  be  excluded,  and  that 
which  is  in  the  cylinder  will  ex- 
pand as  the  piston  descends,  so 
that  when  the  stroke  is  completed 
it  will  occupy  the  entire  capacity. 
The  pressure  of  the  steam  will  then 
be  half  of  its  former  amount,  or 
five  pounds  upon  the  inch. 

During  the  descent  of  the  piston, 
the  pressure  of  the  steam  does  not 
suddenly  decrease  from  ten  pounds 
to  five;  but  it  gradually  declines, 
through  the  successive  intervals, 
until  at  the  final  point  it  yields  that 
force.  It  is  by  this  gradual  expan- 
sion and  diminution  of  pressure  that 
the  superior  action  is  produced. 
Experiments  on  Brass*  Dr.  Young 
made  some  experiments  on  brass, 


EXF 


EXPERIMENTS  IN  BRASS. 


EXT 


froofr  wYdch  he  calculated  the 
height  of  the  modulus  of  elasticity 
of  brass  plate  to  be  4,940,000  feet, 
or  18,000,000tts.  for  its  weight  to 
a  base  of  1  sqoaie  inch.  For  wire 
of  infMar  brass  he  found  the 
Mgfat  to  be  4,700,000  feet. 

Am  cast  brass  had  not  beeii  sub- 
mitted to  experiment,  a  cast  bar 
of  good  brass  was  procured,  with 
which  the  IdUowing  Experiment  was 
made : 

The  bar  was  filed  true  and  regn- 
lar :  its  depth  was  0*45  inch,  and 
breadth  0*7  inch;  the  distance  be- 
tween the  supports  was  12  inches, 
and  the  scale  suspended  firom  the 
middle. 
lb«.  ineh» 

12  bent  the  bar  001 


23 

38 
52 

65 

110 


002 

0*03 
0ra4 


The  bar  was 
relieved  seve- 
ral times,  but 
itteok  no  per- 
^  ceptible  set. 

relieved,  the 
set  was  *01. 


{ 


0*05^ 

018 
f  slipped  between 


163 


the 
J  supports,  bent  more 
I  than  2:  inches,  but  did 
t  not  break. 
Hence  52 lbs.  seems  to  be- about 
the  limit  which  could  not  be 
much  exceeded  without  permanent 
change  of  structure*  I#  is  equiva- 
lent to  a  strain  of  6700ib8.  upon  a 
square  inch,  and  the  corresponding 
extension  is  Ys^  of  its  length.  Ab- 
solute cohesion  above  21,000  lbs. 
per  square  inch.  The  modules  of 
elasticity  according  to  this  experi- 
ment  is  8,930,000  lbs.  for  a  base  of 
an  inch  square.  The  specific  gra- 
vity  of  the  brass  is  8*37,  whence 
we  have  2,460,000  feet  for  the 
height  of  the  modulus*. 
Expression  principally  consists  in  re- 
presenting the  human  body  and  all 
its  parts  in  the  action  suitable  to 
it;  in  exhibiting  in  the  face  the 
several  passions  proper  to  the 
figures,  and  marking  the  motions 

mi. 


they  impress  on  the  other  external 
parts 

Expression,  in  painting,  consists  in 
the  representation  of  those  atti- 
tudes  of  the  body,  and  variations 
of  the  countenance,  which  always 
accompany  and  indicate  the  imme- 
diate influence  of  the  passions  on 
the  mind 

Expression  of  colour.  Every  pas- 
sion and  afi'ection  of  the  mind  has 
its  appropriate  tint;  and  colonr- 
ing,  if  properly  adapted,  lends  its 
aid,  vrith  powerful  effect,  in  the 
just  discrimination  and  forcible  ex- 
pression of  them :  it  heightens  joy, 
warms  love,  inflames  anger,  deep- 
ens sadness,  and  adds  coldness  to 
the  cheek  of  death  itself. 

External  thermometer  (the)  should  be 
a  mercurial  one,  well  esdiausted  of 
air,  and  the  graduated  scale  divided 
to  tenths  of  a  degree,  or  into  quar- 
ters of  a  degree,  or  with  whole 
divisions  large  enough  to  be  di- 
vided into  as  many  parts  by  the 
eye.  Choose  a  locality  for  the 
instrument,  where  it  will  be  well 
exposed  to  the  ambient  air, — apart 
from  the  reflection  of  sunbeams, 
&c., — and  where  it  may  be  dis- 
tinctly read  off  without  inconve- 
nience^ It  should  be  read  off  as 
quickly  as  possible.  For  uniformity 
of  system,  it  should  be  read  off  at 
stated  periods,  the  same  time  at 
which  the  barometer,  &c.,  are 
noted,  and  carefully  vratched  in 
the  interim,  to  see-  whenever  any 
remarkable  change  occurs ;  before 
and  after  storms,  during  eclipses  of 
the  sun  and  moon,  or  the  passage 
of  dense  cloudb  of  vapour,  &c. 

Extract  of^gambogo-  is  the  colouring 
matter  of  gamboge  separated  from 
its  greenish  gum  and  impmrities  by 
solution  in  alcohol  and  predpita* 
tion,  by  whieh  means  it  acquires  a 
powdery  textove,  rendering  it 
miscible  in  oil,  fte;.,  and  capable 
of  use  in  glaiing.  It  is  at  the 
same  time  improved  in  colour,  and 
retains  its  original  property  of 
working^mell  in  vrater  and  gum. 


EXT 


EaeiradoBf  the  exterior  carve  of  an 
archt  measured  on  the  top  of  the 
YOQSsoirs,  as  opposed  to  the  soffit 
or  intrados 

Eye,  a  name  given  to  oertain  circidar 
parts  and  apertoies  in  architectore, 


FARM.  FAR 

but  more  etpedaRy  to  the  central 
drcle  of  the  Ionic  volnte ;  to  the 
circnlar  or  oval  wmdow  in  a  pedi- 
ment; to  a  small  skylight  in  a 
roof,  or  the  aperture  at  the  tnm- 
mit  of  a  capda 


FAB 

Fabbr,  a  name  given  by  the  Romans 
to  any  artisan  or  mechanic  who 
worked  in  hard  materials 
Fabrica,  according  to  the  Romans, 

the  workahop  of  any  mechanic 
FaJbriHa,  according  to  Horace,  me- 
chanics' tools 
Facade,  the  face  or  front  of  any  con- 
siderable building  to  a  street,  court, 
garden,  or  other  place 
Face-piece,  in  ship-building,  a  jnece 
wrought  on  the  fore-part  of  the 
knee  of  the  head,  to  assist  the  con- 
version of  the  main-piece,  and  to 
shorten  the   upper  bolts  of  the 
knee  of  the  head 
Fahrenheit,  a  native  of  Dantzic,  was 
bom  in  1686 :  he  invented  the  scale 
so  called  after  his  name :  he  also  im- 
proved the  thermometer  by  substi- 
toting  mercury  instead  of  spirits  of 
wine,  and  formed  a  new  scale  for 
the  instrument,  founded  on  accurate 
experiments,  fixing   the   freezing 
point  of  water  at  32^,  and  that  ci 
boiHng  at  212° 
Faldetoolj  or  folding  stool,  a  portable 
seat  made  to  fold  up  in  the  man- 
ner of  a  camp  stool :  it  was  made 
either  of  metal  or  wood,  and  some- 
times covered  with  rich  silk 
False  roqf,  the  space  between  the 
ceiling  and  the  roof  above  it,  whe- 
ther the  ceiling  is  of  plaster  or  a 
stone  vault,  as  at  King's  College 
chapel,  Cambridge,  and  St.  Jaques' 
church,  Liege 
Fan-traeefy  vauUtng :  this  was  used 
in    late    Perpendicular  work,    in 
which  all  the  ribs  that  rise  from 
the  springing  of  the  vault  have  the 
same  curve,  and  diverge  equally  in 
every  direction,  producing  an  effect 
like  the  bones  of  a  fan :  very  fine 
examples  of  it  exist  in  Henry  the 


FAR 

Vllth's  chapel,  Westminster,  St. 
George's  chapel,  Windsor,  and 
King's  CoRege  chapel,  Cambridge 

Fanal,  a  pharos  or  lighthouse,  or  the 
lantern  placed  in  it 

Fanum,  a  Roman  temple  or  fane,  usu- 
ally consecrated  to  some  deity 

Fang^  in  mining,  a  niche  cut  in  the 
side  of  an  adit,  or  shaft,  to  serve 
as  an  air  course :  sometimes  a  main 
of  wood  pipes  is  called  a  iahging 

Famiert,  vanes  or  fiat  discs  revolving 
round  a  centro,  so  as  to  produce  a 
current  of  air ;  generally  used  in- 
stead of  bellows  for  forges 

Farm.  Vitnivius  says — "The  mag- 
nitude of  the  buildings  must  de- 
pend wholly  upon  the  quantity  of 
land  attached  to  them,  and  upon 
its  produce.  The  number  of  courts 
and  their  dimensions  must  be  pro- 
portioned to  the  herds  of  cattle 
and  the  quantity  of  oxen  employed. 
The  kitchen  should  be  situated  in 
the  warmest  part  of  the  court,  and 
the  stable  for  the  oxen  contiguous ' 
to  it:  the  stalls  should  be  made 
to  Hce  the  hearth  and  the  east; 
because  when  oxen  are  constantly 
exposed  to  light  and  heat,  they  be- 
come smooth -coated.  No  hus- 
bandman, however  ignorant,  will 
suffer  cattle  to  face  any  other 
quarter  of  the  heavens  than  the 
east.  The  width  of  the  stables 
ought  not  to  be  less  than  ten  nor 
more  than  fifteen  feet,  their  length 
proportioned  to  the  number  of 
yokes,  each  of  which  should  oc- 
cupy an  extent  of  seventeen  feet. 
The  scalding-rooms  should  adjoin 
the  kitchen,  in  order  that  the  ope- 
ration of  cleaning  the  utensils  may 
be  performed  upon  the  spot.  The 
courts  for  sheep,  &c.,  should  be 


FAR 


FEED-PIPE. 


FEE 


80  spadous  as  to  allow  not  less 
than  four  and  a  half  nor  more 
than  six  feet  to  each  animal. 

''  The  granaries  should  he  ahove 
ground,  and  made  to  front  either 
the  north  or  the  north-east,  in  order 
that  the  grain  may  not  be  liable 
to  ferment;  but,  on  the  contrary, 
by  exposure  to  a  cold  atmosphere, 
may  be  preserved  a  long  time :'  all 
other  aspects  encourage  the  pro- 
pagation of  worms  and  insects  de- 
structive to  grain.  The  stables 
should  be  bmlt  in  the  warmest 
part  of  the  villa,  most  distant  from 
the  hearth;  because  when  horses 
9xe  stalled  near  fire  they  become 
rough-coated.  It  is  likewise  ex- 
pedient to  have  stalls  for  oxen  at  a 
distance  from  the  kitchen,  in  the 
open  air :  these  should  be  placed 
60  as  to  front  the  east,  because  if 
they  are  led  there  to  be  fed  in 
winter,  when  the  sky  is  unclouded 
they  will  improve  in  appearance. 
The  bams,  the  hay-yards,  the  corn- 
chambers,  and  the  mills,  ought  to 
be  without  the  walls ;  so  that  the 
farm  maybe  less  liable  to  accidents 
from  fire." 

Farm,  in  Cornish  mining,  that  part 
of  the  lord's  fee  which  is  taken  for 
liberty  to  work  in  tin  mines  only 
that  are  bounded,  which  is  gene- 
rally one-fifteenth  of  .the  whole 

Fascia,  a  fiat  architectural  member  in 
an  entablature  or  elsewhere;  a 
band  or  broad  fillet.  The  architrave 
in  the  more  elegant  orders  of  archi- 
tecture is  divided  into  three  bands, 
which  are  called  fasciae :  the  lower 
is  called  the  first  fascia,  the  middle 
one  the  second,  and  the  U]gper  one 
the  third  fascia. 

Fascia,  the  bands  of  which  the  epi- 
stylium  of  the  Ionic  and  Corinthian 
orders  are  composed.  The  ante- 
pagments  of  Ionic  doorways  were 
generally  divided  into  three  fasciae 
or  oorsse.  Fasciae  were  bands 
which  the  Romans  were  accus- 
tomed to  bind  round  the  legs. 

Fast  and  loose  pulleys,  two  pulleys 
placed  side  by  side   on  a  shaft 

182 


which  is  driven  from  another  shaft 
by  a  band:  when  it  is  required  to 
stop  the  shaft,  the  band  is  trans- 
ferred to  the  loose  pulley 

Fastigium,  the  pediment  of  a  portico ; 
so  called  because  it  followed  the 
form  of  the  roof,  which  was  made 
like  a  triangle,  the  sides  being 
equally  inclined  to  carry  off  the 
water 

Fastigium,  in  architecture,  the  sum- 
mit,  apex,  or  ridge  of  a  house  or 
pediment 

Fatue,  according  to  Vitruvius,  a  nar- 
row passage  which  formed  a  com- 
munication between  the  two  prin- 
cipal divisions  of  a  Roman  house, 
— the  atrium  and  peristylium 

Fay,  in  ship-building,  to  join  two 
pieces  of  timber  close  together 

Feathering,  or  foliation,  an  arrange- 
ment of  small  arcs  or  foils  sepa- 
rated by  projecting  points  or  cusps, 
used  as  ornaments  in  the  mould- 
ings of  arches,  &c.  in  Gothic 
architecture 

Feed-head,  a  cistern  containing  water 
and  communicating  with  the  boiler 
of  a  steam  engine  by  a  pipe,  to 
supply  the  boiler  by  the  gravity  of 
the  water,  the  height  being  made 
sufiScient  to  overcome  the  pressure 
within  the  boiler 

Feed-pipe,  the  pipe  leading  from  the 
feed-pump,  or  from  an  elevated 
cistern,  to  the  bottom  of  the 
boiler  of  a  locomotive  engine 

Feed-pipe  cocks,  those  used  to  regulate 
the  supply  of  water  to  the  boiler  of 
a  locomotive  engine,  and  the  handle 
of  which  is  placed  conveniently  to 
open  and  shut  at  pleasure 

Feed-pipe  strainer,  or  strum,  a  perfo- 
rated half-4pherical  piece  of  sheet 
iron,  after  the  manner  of  the  rose 
end  of  a  watering  pot :  it  is  placed 
over  the  open  end  of  the  feed-pipe 
in  the  locomotive  tender  tank,  to 
protect  it 

Feed-pipes,  the  copper  pipes  reaching 
from  the  clack-box  to  the  pump 
and  from  the  pump  to  the  tender, 
to  convey  water  to  the  boiler  of  a 
locomotive  engine 


FEE 


FENESTRATION. 


FIL 


Feed-pump,  a  forcing-pump,  worked 
by  the  steam  engine,  for  supplying 
the  boiler  with  water 
Feed-pump. plunger y  the  solid  piston, 
or  enlarged  end.of  the  pump-rod, 
fitting    the     stuffing-box    of    the 
pump  of  a  steam  engine 
FeiUnff    timber,    the  act  of  cutting 
down    a    full-grown  tree,    which 
doubtlessly  should  be  done  late  in 
the  autumn,   when  less  moisture 
exists  in  all  trees,  and  which  ren- 
ders the  timber  less  liable  to  dry- 
rot 
FeUpar,  a  mineral  of  foliated  struc- 
ture 
Felucca,  in  navigation,  a  little  vessel 
used  in  the  Mediterranean,  capable 
of  going  either  stem  or  stem  fore- 
most ;  also  a  small  open  boat,  row- 
ed with  six  oars 
F«m«re//,  a  lantern,  louvre,  or  covering 
placed  on  the  roof  of  a  kitchen, 
hall,  &c.  for  the  purpose  of  venti- 
lation or  the  escape  of  smoke 
Femur,  in  architecture,  the  long  flat 
projecting  face  between  each  chan- 
nel of  a  triglyph ;  the  thigh,  or  a 
covering  for  the  thigh 
Fender-pUes,  those  driven  to  protect 

work  either  on  land  or  in  water 
FeneateUa,  the  niche  at  the  side  of  an 
altar  containing  the  piscina ;  a  ves- 
sel for  holding  water  to  wash  the 
hands  of  the  officiating  priest;  also 
a  little  window 
Fenestra,  a  window,  an  entrance    • 
Fenettral:    window-blinds  or  case- 
ments closed  with  paper  or  cloth, 
instead  of  glass,  are  so  termed 
Fenestration,  termed  by  the  Germans 
Fenster-architektur,  is,  in  contra- 
distinction   to   columniation,   the 
-    system  of  construction  and  mode  of 
design  marked  by  windows.  Fenes- 
tration and  columniation  are  so  far 
antagonistic    and    irreconcileable, 
that  fenestration  either  interferes 
with  the  eflfect  aimed  at  by  colum"-^  * 
niation  with  insulated  columns,  as 
in  a  portico  or  colonnade,  or  re- 
duces it,  as  is  the  case  with  an 
engaged  order,  to  something  quite 
secondary  and  merely  decorative. 

183 


Astylar  andfenestratedonght,  there- 
fore, to  be  merely  convertible  terms ; 
but  as  they  are  not,  that  of  co- 
lumnar -fenestrated  has  been  in- 
vented, to  denote  that  mode  of 
composition  which  unites  fenestra- 
tion with  the  semblance,  at  least,  of 
the  other.  Employed  as  a  collec- 
tive term,  fenestration  serves  to 
express  the  character  of  a  building 
or  design  with  regard  to  the  win- 
dows  generally :  thus  it  is  said,  the 
fenestration  is  exceUent,  or  the  con- 
trary,— ornate  or  meagre, — well 
arranged  or  too  crowded, — ^which 
last  circumstance  is  a  very  common 
fault,  and  is  destructive  both  of 
grandeur  and  of  repose. 

FerUory,  a  bier,  or  coffin;  a  tomhj|or 
shrine  ,  C 

Ferrule,  a  metal  ring  fixed  on  Aie 
handle  of  a  tool  to  prevent  the  wood 
from  splitting 

Fesse,  in  heraldry,  a  band  or  girdle 
possessing  the  third  part  of  the 
escutcheon  over  the  middle 

Festoon,  an  ornament  of  carved  work, 
representing  a  vrreath  or  garland 
of  flowers  or  leaves,  or  both  inter- 
woven with  each  other:  it  is  thick- 
est in  the  middle,  and  small  at  each 
extremity,  a  part  often  hanging 
down  below  the  knot 

Festoon,  in  architecture,  an  ornament 
of  carved  work,  in  the  form  of  a 
wreath  or  garland  of  flowers,  or 
leaves  twisted  together 

Fictile,  an  earthen  vessel  or  other 
article,  moulded  and  baked 

Fictor,  among  the  Romana,  an  artist, 
a  deviser,  or  potter 

Field,  in  heraldry,  the  whole  surface 
of  the  shield 

Figuhis,  an  artist  who  makes  fig^es 
and  ornaments 

Filagree,  in  the  arts,  a  kind  of  en- 
richment in  gold  and  silver 

File,  a  well-known  instrument  having 
teeth  on  the  surface  for  cutting 
metal,  ivory,  wood,  &c. 

File,  a  strip  or  bar  of  steel,  the  sur- 
face of  which  is  cut  into  fine  points 
or  teeth,  which  act  by  a  species  of 
cutting  closely  allied  to  abrasion. 


FIN 


FINLAYSON'S  TABLES. 


FIR 


When  the  file  is  nibbed  over  the 
material  to  be  operated  upoD,  it  cuts 
or  abrades  little  shavings  or  shreds, 
which,  from  their  minuteness,  are 
called  file-dusty  and,  in  so  doing,  the 
file  produces  minute  and  irregular 
furrows  of  nearly  equal  depth,  leay- 
ing  the  surface  that  has  been  filed 
more  or  less  smooth,  according^  the 
size  of  the  teeth  of  the  file,  and  more 
or  less  accurately  shaped,  according 
to  the  degree  of  skill  used  in  the  ma- 
nipulation of  the  instrument.  The 
files  employed  in  the  mechanical 
arts  are  almost  endless  in  variety. 

Fmialf  sometimes  called  a  pinnacle, 
but  more  truly  confined  to  the 
bunch  of  foliage  which  terminates 
pinnacles,  canopies,  pedimentti^&c. 
in  Gothic  architecture 

Finite  foret,  a  force  that  acts  for  a 
finite  time,  such  as  the  force  of 
gravity 

F^i^  a  small  flat  face  or  band,  nsed 
principally  between  mouldings  to 
separate  them  from  each  other  in 
classical  architecture:  in  the  Gothic, 
Early  English,  or  Decorated  styles 
of  architecture,  it  is  also  used  upon 
larger  mouldings  and  shafts 

FinkiysofCB  Tablet  of  the  value  of  life 
assurance  and  annuities  differ  in 
several  respects  widely  from  either 
the  Northampton  orthe  Carlisle  cal- 
culated Tables.  In  framing  them  for 
Government  annuities  from  obser- 
vations made  on  the  mortality  in 
tontines  and  amongst  the  holders 
of  Government  annuities,  Mr.  Fin- 
layson,  in  his  calculations,  is  in- 
clined to  take  a  favourable  view  of 
the  duration  of  human  life,  and  his 
Tables  coincide  very  nearly  with 
the  Carlisle,  except  that  he  makes 
a  distinction  between  males  and 
females, — the  latter  being  consi- 
dered rather  longer  lived  than  the 
former.  As  regards  annuities,  these 
observations  may  be  thus  illustrat- 
ed: the  present  value  of  an  an- 
nuity of  £  1  for  the  life  of  a  person 
aged  twenty.five,  calculated  at  4 
per  cent,  interest,  would  be,  ac- 
cording to  the 

184 


Northampton  Tables,  15  4 
Carlisle  do.  ...  17  6 
Government,  Male  .  16  9 
Do.    .    .    .Female.  18  1 

Fire'b4ir/ramefm  alocomotive  engine, 
a  frame  made  to  fit  the  fire-box  on 
which  the  fire-bars  rest :  a  plan  of 
dropping  all  the  bars  at  once  by  a 
moveable  frame,  acted  on  by  a  lever 
and  handle  outside  the  fire-box,  has 
been  frequently  tried,  but  the  action 
of  the  intense  heat  soon  puts  it  out 
of  working  order 

Fire^argf  in  a  locomotive  engine, 
wedge-shaped  iron  bars  fitted  to 
the  fire-box  with  the  thick  side 
uppermost,  to  support  the  fire :  the 
ends  rest  on  a  frame :  they  are  in- 
clined inwards,  with  an  air  space 
between  each,  to  promote  combus- 
tion, and  are  jointed  at  one  end, 
and  supported  by  a  rod  at  the  other, 
so  that  the  rod  being  withdrawn, 
the  bars  fall,  and  the  fire-box  is 
emptied 

Fire-box^  in  a  locomotive  engine,  the 
box  (usually  made  of  copper)  in 
which  the  fire  is  placed.  The  out- 
side is  of  iron,  separated  from  the 
copper  fire-box  by  a  space  of  about 
3  inches  all  round  for  water 

Fire-box  door,  the  door  opening  into 
the  fire-box,  facing  the  locomotive 
tender,  by  which  coke  is  supplied 
to  the  fire 

Firebox  partition:  in  large  fire-boxes 
a  division  is  made  in  the  box,  into 
which  irater  is  admitted :  this  di- 
vision is  about  the  height  of  the 
fire-box  door,  and  divides  the  fire 
into  two  parts  in  a  locomotive  en- 
gine, thereby  increasing  the  heating 
surface  of  the  fire-box 

Fire-box 9tay9,  in  alocomotive  engine, 
deep  strong  iron  stays  bolted  to 
the  top  of  the  copper  fire-box,  to 
enable  it  to  resist  the  pressure  of 
the  steam  :  round  copper  or  iron 
stays  are  also  used  to  connect  the 
outside  shell  to  the  inside  box,  in 
the  proportion  of  about  one  stay  to 
every  4  square  inches  of  flat  surftce 

Fire-brick  or  Fire-bricks  are  used  for 


FIR 


FIRE-BRICKS. 


HR 


lining  fumaceay  and  for  all  kinds  of 
briduwork  exposed  to  intense  heat 
which  would  melt  common  bricks. 
They  are  made  from  a  natoral  com- 
poimd  of  silica  and  alumina,  which, 
when  free  fr«HB  lime  and  other 
fluxes,  is  infusible  under  the  great- 
est  heat  to  which  it  can  be  subjected. 
Oxide  of  iron,  however,  which  is 
present  in  most  days^  renders  the 
clay  fusible  when  the  silica  and 
alumina  are  nearly  in  equal  pro- 
portions, and  those  fire-clays  are 
the  best  in  which  the  silica  is 
greatly  in  excess  over  the  alumina. 
When  the  alumina  is  in  excess, 
broken  cmdbles,  g^ass-house  pots, 
and  old  fire-bricks,  ground  to  pow- 
der, are  substituted  for  the  common 


silidous  sand  nsed  in  the  ordinary 
processes  of  biick-making,  but 
which,  in  this  case,  would  be  in- 
jurious, as  having  a  tendency  to 
render  the  day  ftuible. 

Fire-day  bdng  an  expensiye  ar- 
ticle, it  is  usual,  when  making  fire- 
bricks at  a  distance  from  mines, 
to  mix  with  it  burnt  day,  for  the 
sake  of  economizing  the  clay  and 
diminishing  its  contraction.  Mr. 
Pellatt  states  that  Stourbridge  day, 
when  carefully  picked,  ground,  and 
sifted,  will  bear,  for  brick-making, 
two  proportions  (by  weight)  of 
burnt  clay  to  one  oif  native  day. 

The  follovnng  Table  shows  the 
constituents  of  several  infusible 
clays: 


Authority  .     . 

Dr.  Ure. 

Vauquelin. 

Wrightson. 

Deaeription. 

Kaolin,  or 

porcelain 

clay. 

Plaatic  day  of 
forge  lea  eanx. 

Sagger  clay,  from 

the  Staffordshire 

potteries. 

Silica    .     .    . 
Alumina     •    • 
Iron.     •     •     • 
Lime     •     •     • 
Carbonic  add . 
Water    .     .    . 

52 

47 
0-33 

63 

16 

8 

1 

10 

54-38 
26*55 

8-38 

314 
7-28 

99*33 

98 

99-73 

1 

Rentarka    •    • 

4 

Used  for  making 
glass-house  pots 
and  pottery. 

Used  for  making 
saggars  and  fire- 
bricks. 

Fire-day  is  found  throughout  the 
coal  formation,  but  that  of  Stour- 
bridge is  considered  the  best.  The 
fire-clays  of  Newcastle  and  Glasgow 
are  also  much  esteemed.  Fire- 
bricks are  brought  to  London  from 
Stourbridge  and  from  Wales;  the 
latter,  howcTer^vriU  not  stand  such 
intense  heat  as  the  Stonrbridge 
bricks. 

Fire-bricks  are  also  made  at  the 
village  of  Hedgerly,  near  Windsor, 
of  the  sandy  loam  known  by 
the  name  of  Windsor  loam,  and 
these  are  much  used  in  London 


for  fire-work,  and  also  by  chemists 
for  luting  their  furnaces,  and  for 
similar  purposes. 

The  relative  merits  of  Windsor, 
Wdsh,  and  Stourbridge  fire-bricks 
are  b€«t  shown  by  their  yalue  in 
the  market. 

The  following  prices  are  from 
the  '  Contractor's  Pocket-Book  for 
1850.'     They  include  carriage  to 
London  and  delivery  on  the  works : 
Fire-bricks  per  m.      £.   9.    d, 
Windsor  ...    5     8     0 
Welsh      ...    8  12    0 
Stourbridge  .    .11     6    0 


185 


FIR 


FIRES  OF  THE  ANCIENTS. 


FIR 


Fire-bricks,  The  parts  of  furnaces 
exposed  to  heat  are  built  of  bricks 
made  of  a  description  of  clay  which 
is  to  different  extents  infusible,  the 
qualities  chosen  for  use  being  regu- 
lated by  the  degree  of  heat  to  which 
they  are  to  be  exposed.  They  are 
known  in  commerce  by  the  names 
of  Bristol,  Stourbridge,  Newcastle, 
Welsh,  and  Windsor  bricks.  The 
first  of  these  are  composed  almost 
entirely  of  silex,  and  are  infusible 
at  the  greatest  heat  of  the  blast- 
furnace ;  but  they  are  very  costly, 
and  seldom  used.  The  second 
.  quality  are  made  from  clay  found 
in  the  neighbourhood  of  Stour- 
bridge, lying  in  a  stratum  of  con- 
siderable thickness  between  the 
upper  soil  and  the  coal  formations: 
they  are  used  in  the  construction  of 
furnaces  required  to  resist  great 
heat,  such  as  those  for  smelting 
iron  ores,  glass-making,  &c.|  and 
sometimes  for  the  linings  of  retort 
ovens :  for  this  latter  purpose  they 
are  considered  too  expensive,  except 
for  the  arch  immediately  over  the 
furnace,  as  the  heat  is  not  intense. 
The  third  variety  are  composed  of 
the  clay  lying  above  the  coal  mea- 
sures in  Northumberland,  and  for 
the  construction  of  retort  furnaces 
and  ovens  are  the  most  desirable. 

Fire-dampf  in  coal  mines,  is  impure 
carburetted  hydrogen 

Fire-place f  a  space  within  a  chimney- 
piece  for  the  burning  of  fuel  to 
warm  the  temperature  of  the  air, 
and  in  communication  with  a  shaft 
or  chimney-flue 

Fire-tubes,  or  tube-flues,  are  those 
through  which  the  fire  passes,  for 
obtaining  a  large  heating  surface, 
fixed  longitudinally  in  the  middle 
compartment  of  a  locomotive  en- 
gine, between  the  fire-box  and 
smoke-box 

Fires  of  the  Ancients,  Palladio  says, 
— **  Finding  that  this  subject  about 
fires  of  the  ancients  had  not  been 
treated  of  distinctly  by  any  body, 
I  resolved  ta  compose  something 
about  it.    We  are  ignorant  of  most 

186 


things  delivered  thereupon  by  the 
ancients  which  might  give  us  some 
light  upon  the  matter:  we  must 
have  recourse  to  the  inventions  of 
later  times,  thereby  gradually  to 
obtain  a  more  ample  knowledge  of 
it.  The  Romans  were  sensible  that 
a  continual  flame  and  a  great  heat 
from  live  coals  were  hurtful  to  the 
eyes;  they  therefore  went  very 
wisely  about  finding  out  a  remedy. 
They  found  how  dangerous  it  was 
to  carry  fire  about  the  house  from 
one  room  to  another.  Stoves  are 
an  abominable  invention:  they 
cause  a  continual  stench,  swell  the 
head,  and  make  men  drowsy,  dull, 
and  lazy.  Most  people  that  use 
them  grow  tender  and  weak :  some 
cannot  stir  out  of  those  rooms  all 
the  winter.  The  ancients  used  to 
light  their  fire  in  a  small  furnace 
under  the  earth.  Thence  they 
conveyed  a  great  many  tubes  of 
different  sizes  into  all  the  different 
stories  and  rooms  of  the  house, 
which  tubes  or  pipes  were  invisi- 
ble, but  laid  in  ihe  thickness  of  the 
walls  and  ceilings,  just  like  water- 
pipes.  Each  of  these  opened  at 
that  part  of  the  furnace  which 
joined  to  the  very  wall  of  the  house, 
and  through  these  ascended  the 
heat,  which  was  let  in  whenever  they 
had  a  mind  it  should,  whether  in 
dining-rooms,  bed-chambers,  or 
closets,  much  in  the  manner  as  we 
see  the  heat  or  steam  of  water 
contained  in  an  alembic  to  ascend 
and  warm  the  parts  most  distant 
from  the  fire-place.  The  heat  in 
that  manner  used  to  spread  so 
equally  that  it  warmed  the  whole 
house  alike.  It  is  not  so  with 
chimneys  or  hearths ;  for  if  you 
stand  near,  you  are  scorched;  if  at 
any  distance,  you  are  frozen ;  but 
here  a  very  mild  warm  air  spreads 
all  around,  according  as  the  fire 
that  warms  the  pipes  laid  along  the 
wall  opposite  to  the  hearth  is  more 
or  less  burning.  Those  pipes  which 
dispensed  the  •heat  did  not  open 
into  the  very  furnace,  on  purpose 


Flu 


FLAMBOYANT  STYLE. 


FLE 


that  neither  smoke  nor  flame  should 
get  into  them,  but  only  a  warm 
steam  should  enter,  which  they  let 
out  again ;  thereby  creating  a  con- 
tinual  moderate    heat.     The  fire 
needed  not  to  be  large,  provided 
it  was  continual,  to  supply  these 
\     confined  and  enclosed  pipes  with  a 
sufficient  power  of  warming.   They 
dressed  their  meat  at  the  mouth  of 
\     the  furnace;    and  all    along  the 
walls  were   disposed   kettles,    or 
other  vessels,  filled  with  hot  water, 
to  keep  the  meat  warm.'' 
Ftr-poleSf    small  trunks  of  fir-trees, 
from  10  to  16  feet  in  length;  used 
in  rustic  buildings  and  out-houses 
Fitht  a  machine  employed  to  hoist 
and  draw  up  the  flukes  of  a  ship's 
anchor  towards  the  top  of  the  bow, 
in  order  to   stow  it  after  it  has 
been  catt^ 
Future,  or  Gulley,  is  that  crack  or 
split   in  the   strata  of  the   earth 
which  is  the  receptacle  of  mineral 
particles,  whose  contents  are  styled 
a  Mode* 
Fiituea,  among  the  Romans,  an  in- 
strument used  for  ramming  down 
pavements    and    threshing-floors, 
and  the  foundations  of  buildings 
Fistula,   a  water-pipe,  according  to 
Yitruvius,  who  distinguishes  three 
modes  of   conveying   water:   by 
leaden  pipes,  by  earthen  pipes,  and 
by  channels  of  masonry 
Five  species  of  temples  (the).  Thereare 
five  species  of  temples :  namely,  the 
pycnostyle,  in  which  the  columns 
are  placed  far  apart;  the  systyle, 
in  which  they  are  more  remote; 
the  diastyle,  whose  columns  are  at 
an  ample  distance  from  each  other; 
the  araeostyle,  in  which  the  inter- 
vals between  the  colmnns  are  too 
great ;  and  the  eustyle,  whose  inter- 
columniations   are   justly  propor- 
tioned.    In  the  pycnostyle  species 
the  interval  between  the  columns 
is  equal  to  one  diameter  and  a  half: 
there  is  an  instance  of  this  in  the 
temple  of  Julius,  and  another  in 
the  temple  of   Venus,    which   is 
erected  in  the  forum  of  Csesar :  in 

187 


all  temples  of  this  species  the  same 
interval  between  tiie  colunms  is 
observed.  In  the  systyle  species 
there  should  be  an  interval  between 
the  columns  equal  to  twodiameters : 
this  arrangement  would  leave  the 
space  between  the  plinths  of  the 
bases  of  the  columns  equal  to  the 
extent  of  the  plinths  themselves. 

Flake  white  is  an  EngUsh  white  lead, 
in  the  form  of  scales  or  plates,  some- 
times grey  on  the  surface.  It  takes 
its  name  from  its  figure,  is  equal  or 
sometimes  superior  to  crems  white, 
and  is  an  oxidized  carbonate  of 
lead,  not  essentially  differing  from 
the  best  of  the  above.  Other  white 
leads  seldom  equal  it  in  body ;  and 
when  levigated,  it  is  called  *  body- 
white.' 

Flamboyant  Style  of  Architecture, 
the  decorated  and  very  ornamental 
style  of  architecture,  of  French  in- 
vention and  use,  and  contemporary 
in  France  with  the  Perpendicular 
style  in  England.  One  of  the  most 
striking  and  universal  features  is 
the  waving  arrangements  of  the 
tracery  of  the  windows,  panels,  &c. 
The  foliage  used  for  enrichments 
is  well  carved,  and  has  a  playful 
and  frequently  a  good  effect. 

Flarminff,  the  internal  splay  of  a  win- 
dow-jamb 

Flaring,  in  ship-building,  over-hang- 
ing, as  in  the  topside  forward 

Flatting,  in  house-painting,  a  mode 
of  painting  in  oil  in  which  the 
surface  is  left,  when  finished,  with- 
out gloss.  The  material  is  pre- 
pared with  a  mixture  of  oil  of  tur- 
pentine, which  secures  the  colours, 
and,  when  used  in  the  finishing, 
leaves  the  paint  quite  dead. 

Flemish  bricks  are  used  for  paving : 
seventy-two  wiU  pave  a  square 
yard :  they  are  of  a  yellowish  co- 
lour, and  harder  than  the  ordinary 
bricks 

Flemish  School  of  Painting,  This 
school  is  highly  recommended  to 
the  lovers  of  the  art  by  the  disco- 
very, or  at  least  the  first  practice, 
of  painting  in  oil.     It  has  been 


FLO 


FLORENTINE  SCHOOL. 


FLO 


generally  attributed  to  John  Van 
Eyck,  who  was,  it  is  said,  acciis- 
tomed  to  yarnisb  his  distemper 
pictures  with  a  composition  of  oils, 
which  was  pleasing  on  account  of 
the  lustre  it  gave  them.  In  the 
course  of  his  practice  he  came  to 
mix  his  colours  with  oil,  instead  of 
water,  which  he  found  rendered 
them  brilliant  without  the  trouble 
of  yamishing.  From  this  and  sub- 
sequent experiments  arose  the  art 
of  painting  in  oil ;  and  this  won- 
derful discovery,  whether  made  by 
Van  Eyck  or  not,  soon  acquired 
notice  all  over  Europe.  The  atten- 
tion of  the  Italian  painters  was  soon 
excited.  John  of  Bruges  was  the 
founder  of  painting  as  a  profession 
in  Flanders.  Peter  Paul  Rubens 
was  the  founder  of  the  art. 

Floatf  a  flat  piece  of  stone  or  other 
material  attached  to  a  valve  in  the 
feed-pipe  of  the  boiler  of  a  steam 
engine,  and  supported  upon  the  sur- 
face of  the  water  by  a  counter- 
weight; used  either  for  showing 
the  height  of  the  water,  or  regu- 
lating the  supply  from  the  cistern 

FlookoHf  in  Cornish,  an  earth  or  clay 
of  a  slimy  glutinous  consistence ; 
in  colour,  for  the  most  part  blue  or 
white,  or  compounded  of  both 

FlooT'holhWf  in  ship-building,  an 
elliptical  mould  for  the  hollow  of 
the  floor  timbers  and  lower  fiit- 
tocks 

Floors,  in  early  English  domestic  ar- 
rangements,  were  generally  covered 
with  rushes,  carpets  being  seldom 
used  for  such  purposes  even  at  the 
dose  of  Elizabeth's  reign,  although 
instances  occur  of  tapestry  cloths 
for  the  feet  to  rest  upon  as  early 
as  Edward  I.  It  does  not,  indeed, 
appear  to  have  been  the  custom  at 
any  time  to  leave  floors  bare, 
whether  boarded  or  paved.  Our 
poets,and  particularly  Shakespeare, 
all  spieak  of  rushes  and  other  vege- 
table  substances  being  strewed  in 
the  principal  apartments. 

FTooT'timders,  in  ship-building,  are 
those  placed   immediately  across 

188 


the  keel,  and  upon  which  the  bot- 
tom  of  the  ship  is  framed 

JPhraiif  an  exceedingly  small-grained 
tin,  scarcely  perceivable  in  the 
stone,  though  perhaps  very  rich 

Florentine  lake  colour  is  extracted 
from  the  shreds  of  scarlet  cloth : 
the  same  may  be  said  also  of 
Chinese  lake 

Florentine  School  ofPainiing,  This 
school  is  remarkable  for  greatness ; 
for  attitudes  seemingly  in  motion ; 
for  a  certain  dark  severity ;  for  an 
expression  of  strength  by  which 
grace  is  perhaps  excluded ;  and  for 
a  character  of  design  approaching 
to  the  gigantic.  The  productions 
of  this  school  may  be  considered 
as  overcharged ;  but  it  cannot  be 
denied  that  they  possess  an  ideal 
majesty  which  elevates  human  na- 
ture above  mortality,  ^he  Tuscan 
artists,  satisfied  with  commanding 
the  admiration,  seem  to  have  con- 
sidered the  art  of  pleasing  as  be- 
neath their  notice.  This  school 
has  an  indisputable  title  to  the 
veneration  of  all  the  lovers  of  the 
arts,  as  the  first  in  Italy  which  cul- 
tivated them. 

Fkjwer-garden  (the)  <' should  be  an 
object  detached  and  distinct  from 
the  general  scenery  of  the  place ; 
and  whether  large  or  small,  whe- 
ther varied  or  formal,  it  ought  to 
be  well  protected  from  hares  and 
smaller  animals  by  an  inner  fence : 
within  this  enclosure  rare  plants 
of  every  description  should  be  en- 
couraged, and  a  provision  made  of 
soil  and  aspect  for  every  difiTerent 
class.  Beds  of  bog-earth  should 
be  prepared  for  the  American 
plants :  the  aquatic  plants,  some  of 
which  aro  peculiarly  beautiful, 
should  grow  on  the  surface  or 
near  the  edges  of  water.  The  nu- 
merous class  of  rock-plants  should 
have  beds  of  rugged  stone  pro- 
vided for  their  reception,  with- 
out the  afi'ectation  of  such  stones 
being  the  natural  production  of  the 
soil;  but,  above  all,  there  should 
be  poles  or  hoops  for  those  kinds 


FLO 


FONT. 


FON 


of  creeping  plants  which  sponta- 
neously form  themselves  into  grace- 
ful festoons,  when  encouraged  and 
supported  by  art/^ 
Fhwer-garden.     There  is  no  orna- 
ment of  a  flower-garden  more  ap- 
propriate than  a  conservatory  or 
greenhouse,    where    the    flower- 
garden   is   not  too  far  from  the 
house;    but   amongst  the   refine- 
ments of  modem  luxury  may  be 
reckoned  that  of  attaching  a  green- 
house  to  some  room  in  the  man- 
sion. 
Flueean,  in  mining,  a  soft  clayey  sub- 
stance, generally  found  to  accom- 
pany the  cross  courses  and  slides 
Fhikej  in   mining,    the  head  of  a 
charger;  an  instrument  used  for 
cleansing    the    hole   previous    to 
blasting 
Fbuh,  a  term  common  to  workmen, 
and  applied  to  surfaces  which  are 
on  the  same  plane 
FMings  or  Flutes^  the  hollows  or 
channels    cut    perpendicularly  in 
the  shafts  of  columns,  &c.|  in  clas- 
sical architecture:  they  are  used 
in  the  Doric,  Ionic,  Corinthian,  and 
Composite  orders 
PluXf  in  metallurgy,  saline  matters 
which  facilitate  the  fusion  of  ores 
and  other  substances  which  are  not 
easily  fusible  in  assays;  used  also  in 
the  redaction  of  ores 
Fly,  in  mechanics,  that  part  of  a 
machine  which,  being  put  in  mo- 
tion, regulates  the  rest 
Fly-wheel,  a  wheel  with  a  heavy  rim, 
fixed  upon   the  crank-shaft  of  a 
land  engine,  for  the  purpose  of 
equalizing  the  motion  by  the  cen- 
trifugal force  absorbing  the  sur- 
plus force  at  one  part  of  the  ac- 
tion, to  distribute  it  again  when 
the  action  is  deficient 
Flyers,  stairs  that  go  straight  and  do 
not  vrind,  the  fore  and  back  part 
of  each  stair  and  the  ends  respect- 
ively being  parallel  to  each  other 
F0CU8,  among  the  Romans,  an  altar, 
a  fire-place  or  hearth :  hence  the 
Latin  motto,  '  pro  aris  et  focis,' — 
*  for  our  altws  and  fire-sides ' 

189 


Fodina,  a  mine  or  quarry 

Foge,  Cornish,  a  forge  or  blowing- 
house  for  smelting  tin 

FoUe,  foliation;  the  spaces  between 
the  cusps  of  the  leatherings  of 
Gothic  architecture 

Font,  a  font,  or  a  natural  spring  of 
water,  frequently  oonyerted  into 
ornamented  fonntains  by  the  Greeks 
and  the  RAmim«.  The  latter  also 
erected  e<fifices  of  various  degrees 
of  splendour  over  natural  springs, 
such  as  the  Grotto  of  Egeria,  near 
Rome,  where  the  natural  cave  is 
converted  by  the  architect  into  a 
temple. 

Foni^  the  Tessd  which  contains  the 
water  for  the  purposes  of  baptism. 
The  font  is  tbe  only  relic  of  our 
ancient  arcUtectnre  which  in  its 
form  is  at  all  analogous  to  the 
Grecian  and  Roman  vases.  The 
shape  which  has  at  different  pe- 
riods been  given  to  it  is  a  subject 
of  some  interest.  Norman  fonts 
are  generally  square  or  circular; 
the  first  frequently  placed  on  five 
legs ;  but  which  may  be  the  older 
form,  the  square  or  circle,  is  not 
yet  known.  The  circular  form 
continued  to  be  much  used  during 
the  Eariy  English  period ;  so  occa- 
sionally was  the  square.  Through- 
out the  continuance  of  the  Deco- 
rated style,  the  octagon  was  gene- 
rally used,  sometimes  the  hexagon. 
During  the  Perpendicular  style,  the 
octagon  was  almost  always  used. 
Until  the  Reformation,  and  occa- 
sionally after,  dipping  was  prac- 
tised in  this  country.  Pouring 
or  sprinkling  was  not  unusual  pre- 
vious to  the  Reformation;  for  as 
early  as  the  year  754,  pouring,  in 
cases  of  necessity,  was  declared  by 
Pope  Stephen  III.  to  be  lawful; 
and  in  the  year  1311,  the  Council 
of  Ravenna  declared  dipping  or 
sprinkling  indifferent :  yet  dipping 
appears  to  have  been  in  this  coun- 
try the  more  usual  mode.  The 
Earl  of  Warwick,  who  was  bom  in 
1381,  was  baptized  by  dipping :  so 
Prince  Arthur  (eldest  son  of  Henry 


FORCING-PUMP. 


FOR 


Vll.),  King  Edward  VI.,  and  Que 
Elizabeth,  were  all  baptized  in 
wmilu-  m 


Font  of  the 

Foal,  an  andeiit  measure  ot  tin,  con- 
taining two  gallom  i  nowanominal 
measure,  but  in  weight  60  Ihi.;  also 
a  lineal  measure  of  twelve  inches 

Fool-pace,  the  dais  or  raised  floor  at 
the  upper  end  of  an  ancient  hall 

Fool-plait,  the  platform  on  which  the 
ensine-man  and  fire-man  of  a  loco- 
■DOtive  engine  attend  to  their  duties 

Fool-tfali,  &e  plinth  or  base  of  a 

Fool-vahe,  the  valve  in  the  passage 
between  the  condenser  and  ur. 
pump  of  an  engine,  opening  towards 
the  ^-pump 

Fool-valeing,  the  plank  withinaide 
a  ship,  below  the  lower  deck 

Force  of  the  Kijid.  Air,  when  in 
continuous  motion  in  one  direction, 
becomes  a  very  useful  agent  of 
machinery,  of  greater  or  less  energy 
according  to  the  velocity  with  which 
it  moves.  Were  it  not  for  its  vari- 
ability in  direction  and  force,  and 
the  consequent  fiuctuationa  in  its 
supply,  scarcely  any  more  appro- 
priate first  mover  could  generally 
be  wished  for ;  and  even  with  all 
its  irregulaitty,  it  is  still  so  useful 
as  to  require  a  separate  considera- 

190  ^^ 


The  force  with  which  air  strikes 
against  a  moving  suri'ace,  or  irith 
which  the  wind  strikes  against  a 
quiescent  surface,  is  nearly  as  the 
square  of  the  velocity ;  or,  more 
corrcclly,  the  eiponent  of  the  ve- 
locity varies  between  2'03  and  2-05; 
M  that  in  most  practical  cases  the 
eiponent  2,  oi  that  of  the  square, 
may  be  employed  without  fear  of 

Foreept,  tongs  used  by  smiths  io  take 
the  hot  metat  from  the  lire 

Force-pumpt,  the  plunger  pumps  for 
supplying  the  boiler  of  a  locomo- 
tive engine  :  the  plunger  rods  are 
connected  to  the  piston-rods  of  the 
steam  cyhnder 

Forcer,  in  Cornish,  a  small  pnmp 
worked  by  band,  used  in  sinking 
small  simples,  dippas,  or  pita 

FoTcing.pTin^  (the)  differs  but  little 
from  a  syringe :  the  Utter  receives 
and  expels  a  liquid  through  the 
same  passage,  but  the  former  has  a 
separate  pipe  for  its  discharge,  and 
both  the  receiving  and  discharging 
orifices  are  covered  with  valves. 
By  this  arrangement  it  is  not  ne- 
cessary to  remove  a  pump  from  the 
liquid  to  transfer  the  contents  of  its 
cylinder,  as  is  done  with  the  sy- 
ringe, but  the  operation  of  forcing 
up  water  may  be  continuous,  while 
the  instnunent  is  immoveable.  A 
forcing-pump,  therefore,  is  merely 
a  syringe  furnished  with  an  induc- 
tion and  eduction  valve, —  one 
through  which  water  enters  the 
cylinder,  the  other  by  which  it  es- 
capeslromit.  Theordinaryfordng- 
pump  has  two  valves  ;  the  cylinder 
is  placed  above  the  surface  of  the 
water  to  be  raised,  and  consequently 
is  charged  by  the  pressure  of  the 
atmosphere:  the  machine,  there- 
fore, is  a  compound  one,  differing 
from  that  described,  which  is 
purely  a  forcing-pump,  the  water 
entering  its   cylinder  by   gravity 

Fortcaallr,  a  short  deck  at  the  fore- 
part of  a  ship,  above  the  upper 
deck,  on  which  castles  were  for- 


FOR 


FOSSES  D'AISANCES. 


FOS 


merly  erected,  or  places  to  shelter 
the  men  in  time  of  action 

Fore-foott  the  foremost  piece  of  the 
keel  of  a  vessel 

Fore-groundj  the  front  of  a  picture 

Foreytiy  an  ancient  term  to  signify  a 
drain  or  cesspool 

Forge,  a  smith's  furnace  for  heating 
metals,  to  render  them  soft  and 
more  malleable 

Fork,  a  short  piece  of  steel  ^which  fits 
into  one  of  the  sockets  or  chucks 
of  a  lathe,  and  is  used  by  wood- 
turners for  carrying  round  the  piece 
to  be  turned :  it  is  flattened  at  the 
end,  like  a  chisel,  but  has  a  pro- 
jecting centre  i>oint,  to  prevent  the 
wood  from  moving  laterally 

Formosity,  beauty,  fairness,  &c. 

Form-peysy  an  ancient  term  for  form- 
pieces;  the  lower  terminations  of 
mullions  which  are  worked  upon  sills 

Formg  and  motions  of  tools.  The 
principles  of  action  of  all  cutting 
tools,  and  of  some  others,  whether 
guided  by  hand  or  by  machinery, 
resolve  themselves  into  the  simple 
condition,  that  the  work  is  the 
combined  copy  of  the  form  of  the 
tool  and  of  the  motion  employed : 
thos  the  geometrical  definitions  em- 
ployed convey  the  primary  ideas  of 
lines,  superficies,  and  solids;  that  is, 
the  line  results  from  the  motion  of 
a  point,  the  superficies  from  the 
motion  of  a  line,  and  the  solid  from 
the  motion  of  a  superficies. 

Formula  (pi.  FormukB),  a  prescribed 
rule  in  arithmetic  or  mathema- 
tics ;  a  maxim :  in  law,  an  action, 
process,  or  indictment 

Formulary,  a  book  containing  set 
forms,  rules,  or  models 

Fornax,  among  the  Romans,  a  kiln 
for  baking  pottery 

Forum,  a  large  open  space  used  by  the 
Romans  for  the  sale  of  merchan- 
dise, and  for  public  assemblies ;  also 
a  court  of  justice 

Forum  and  Basilica.  The  Greeks 
built  their  forum  with  spacious 
porticoes,  two  tiers  in  height,  ar- 
ranged in  a  square  form :  the  co- 
lumns of  the  porticoes  were  placed 


at  small  intervals  from  each  other, 
supporting  stone  or  marble  enta- 
blatures ;  and  galleries  were  made 
over  the  lacunaria  of  the  lower 
porticoes,  or  places  of  exercise. 
In  Italy,  the  mode  of  constructing 
the  forum  was  dififerent;  because, 
by  a  custom  sanctioned  by  its  anti- 
quity, the  show  of  gladiators  was 
exhibited  there ;  and  therefore  the 
intervals  between  the  columns  sur- 
rounding the  area  were  greater. 
The  lower  porticoes  were  occupied 
as  the  ofiSces  of  bankers,  which  si- 
tuation was  calculated  to  faciUtate 
the  management  of  the  public  re- 
venue :  the  upper  contained  seats 
for  the  spectators  of  the  diversions 
practised  in  the  forum. 
Fortification,  the  science  of  military 
architecture ;  a  defensive  building 
Forward,  the  fore-part  of  a  ship 
Fosses  d^aisances :  the  cesspools  of 
Paris  are  so  called;  and  they  are 
usually  made  3'"'00  long  in  the 
clear  by  l^'TO,  by  V^'bQ,  to  the 
springing  of  the  semicircular  head 
(9  ft.  10  in.  X  5  ft.  7  in.  x  4  ft.  11 
in.  English,  nearly):  a  man-hole, 
l™-00  by  0«-35  is  left  for  the  pur- 
poses of  emptying  and  visiting  them 
(3  ft.  3J^  X  1  ft.  2  in.)  The  walls 
which  surround  them,  as  well  as 
the  bottom,  are  exclusively  formed 
of  such  materials  as  are  most  effica- 
cious in  preventing  the  filtration 
of  the  matters  contained  within 
them.  Of  late  years  the  usual 
custom  has  been  to  employ  the 
meuliere,  or  mill-stone,  bedded 
in  mortar  composed  of  Ume  and 
cement ;  the  inside  being  well 
pointed,  and  rendered  throughout 
with  this  mortar.  No  cesspool  is 
allowed  to  be  used  until  after  an 
examination,  to  be  certified  by  the 
municipal  authority.  Any  infil- 
tration to  a  neighbour's  property 
gives  a  title  to  damages,  and  the 
architect  and  builder  are  both  re- 
sponsible for  ten  years  to  the  pro- 
prietor, as  also  to  the  neighbours, 
in  case  any  nuisance  arises  from  de- 
fects in  the  execution  of  the  works. 


191 


FOS 


FOSSES  D'AISANCES. 


FOS 


When  the  cesspools  require  clean- 
ing, notice  is  given  to  the  Board 
of  Pahlic  Health  (aux  agents  de  la 
salubrity  pubtique)i  who  authorize 
and  direct  the  operations.  In  win- 
ter these  are  earned  on  between 
10  P.M.  and  7  A.  M. ;  and  in  sum- 
mer, between  11  p.m.,  and  6  a.m. 
The  carts,  as  well  as  all  the  other 
material  of  the  nightmen,  are  under 
the  inspection  of  the  above-named 
officers,  and  must  be,  as  nearly  as 
possible,  both  water-tight  and  air- 
tight. They  contain  not  more  than 
2"''00  cube  each,  or  nearly  71  ft. 
cnbe  English. 

The  contents  of  the  cesspools  are 
usually  (especially  in  the  modem 
houses)  sufficiently  fluid  to  allow 
of  their  extraction  by  pumps.  In 
this  case  a  small  furnace  is  placed 
over  the  bung  of  the  cart,  to  bum 
the  gas  as  it  rises :  the  bung  itself 
is  plastered  over  directly  the  cart 
is  filled.  When  the  contents  are  too 
solid  to  be  pumped  out,  they  are 
conveyed  fttmi  belowin  small  vessels 
of  wrought  iron,  called  *  tinettes,' 
holding  about  3i  feet  '(-x^th  of 
a  metre  cube)  each;  and  the 
lids  are  plastered  over  before  the 
vessels  are  removed  from  the  cess- 
pool. 

Of  late  years  a  system  of  what 
are  called  *  fosses  mobiles^  has  been 
introduced  into  the  better  class  of 
houses.  It  consists  of  air-tight 
tubs,  placed  in  a  vault  (rendered 
also  as  air-tight  as  possible),  which 
receive  the  ends  of  the  soil-pipes. 
These  tubs  are  removed  at  stated 
intervals,  the  openings  plastered 
over,  and  may  in  that  state  be 
transported  at  any  time  of  the  day. 
This  system  obviates  the  terrible 
infection  of  the  old  kind  of  cesspool, 
and  is  gaining  rapidly.  Indeed*  as 
the  Fr^ch  people  are  fond  of  gilt 
ornaments  in  their  dweUings,  and 
the  gases  from  the  cesspools  turn 
them  black  at  once,  unless  great 
precautions  be  observed  in  covering 
them,  whenever  a  cesspoolisopened, 
it  is  easy  to  understand  that  the 


*^ fosses  mobiies,*  which  obviate  this 
inconvenience,  should  become  of 
general  use. 

Until  of  late,  all  the  carts  were 
obliged  to  pass  through  the  Bar- 
riere  du  Combat  to  deposit  their 
contents  at  the  laystalls  of  Mont- 
faucon ;  but  some  new  works  have 
been  constructed  at  Bondy,  so  as 
to  allow  the  suppression  of  this 
gigantic  nuisance  at  the  inunediate 
gates  of  Paris. 

The  cleaning  of  the  cesspools  of 
Paris  is  executed  by  several  private 
companies,  the  most  important  of 
which  is  'La  Compagnie  Richer,' 
who  do  at  least  one-half  of  this 
business:  their  capital  was  about 
JS 200,000,  in  Und,  plant,  and  build- 
ings. They  employ  150  horses  and 
300  men,  of  whom  60  are  for  the 
repairs  of  the  plant.  Their  charge 
is  8f.,  9f.,  and  lOf.  per  metre  cube 
(35ifeetEnglish,nearly),  according 
to  the  distance. 

No  cesspool  is  allowed  to  be  used 
after  being  emptied  until  it  has 
been  visited  by  an  'agent  de  la 
salubrite,'  to  ascertain  whether  it 
be  water-tight. 

The  laystalls  of  Montfauoon  con- 
sist of  two  large  reservoirs,  at  a 
high  level,  into  which  the  carts  are 
emptied.  These  reservoirs  are  about 
2^  acres  superficial,  and  apparently 
12  feet  deep,  with  a  dam  between 
them,  to  allow  of  one  being  used 
when  the  other  is  being  emptied. 
An  overflow  drain,  with  sluice-gates 
at  each  end,  allows  the  liquid  matter 
to  run  ofl^  to  a  large  basin  on  a 
lower  level,  where  it  deposits  any 
thing  which  may  be  merely  in  a 
state  of  mechanioBl  suspension.  On 
the  banks  of  this  reservoir  are  some 
important  sal-ammoniac  works.  I  n 
the  centreis  also  a  sluice-gate,  which 
allows  the  surjdus  liquid  matters  to 
pass  into  two  smaller  reservoirs, 
where  deposition  takes  place  with- 
out any  interference  from  the  pump- 
ing  apparatus  of  the  chemical  works. 
From  thence  the  waters  pass  off  into 
four  other  basins,  in  which  any 


FOS 


FOUNDATIONS. 


FOU 


fertilizing  properties  they  may  con- 
tain are  precipitated  by  means  of 
straw,  dead  leaves,  &c.,  and  the 
water,  comparatively  pure,  is  at 
leng;th  let  off  into  the  main  sewer, 
which  discharges  itself  into  the 
Seine,  helow  Paris.  The  surface 
of  the  intermediate  basins  is  about 
250"-  by  60"»*  (or  3f  acres) ;  that 
of  the  four  last  basins  is  about  350"^* 
by  110"'  (or  nearly  9^  acres). 

These  reservoirs  do  not  belong 
to  the  city  of  Paris,  and  some  diffi- 
culties have  arisen  from  the  pro- 
posal to  remove  them :  all  the  carts 
containing    the    night-soil    being 
obUged  to  discharge  at  Montfau- 
con,  the  farming  of  the  contents 
of  the  basins  became  a  source  of 
considerable  profit.    They  were  let 
on  the  last  occasion  for  a  sum  of 
500,500  francs  per  annum  (£  20,020 
sterling) ;  the  previous  letting  hav- 
ing been  166,000  francs  (JS6640 
sterling).    The  increased  rent  and 
the  exorbitant  wages  paid  during 
the  republican  excitement  of  1848 
proved  injurious  to  the  company. 
The  ground  occupied  by  the  town, 
moreover,  is  not  sufficiently  exten- 
sive for  the  operations  connected 
with  the  manipulation  of  the  *  pou- 
drette,*    and    the   company  were 
obliged  to  rent  about  7i  acres  more 
land  for  the  purpose  of  spreading 
and  drying  the  compost.   The  land 
necessary  for  this   operation  had 
been  taken  on  lease  by  the  out- 
going company,  and  they  succeed- 
ed in  obtaining  a  sum  of  £  60,000 
for  the  remainder  of  their  term,  as 
no  other  land  was  to  be  had  in  the 
neighbourhood. 

The  rent  and  libour  in  conversion 
costs  the  company  from  JS  12,000 
to  £  1 6,000  per  annum.  The  '  pou- 
drette'  is  sold  to  agriculturists  at 
8  francs  le  setier,  a  measure  equal 
to  12  bushels  English. 

In  one  plan  adopted  for  empty, 
ing  the  cesspools,  the  carts  are 
made  of  strong  boiler  plate ;  they 
are  placed  under  an  air-pump, 
and  exhausted ;  the  pipes  are  con- 

m 


nected  with  the  carts  and  the  cess- 
pools, and  the  atmospheric  pressure 
on  the  latter  forces  up  the  liquid 
contents. 

Investigations  have  been  made 
respecting  the  general  health  of 

*  the  workmen  employed  at  Mont- 
faucon,  the  reservoir  of  all  the  ex- 
crementitious  matter  of  a  city  which 
contains  about  1,000,000  inhabi- 
tants,  and  it  has  been  ascertained, 
that  although  they  were  not  af- 
fected by  the  cholera  in  1849,  they 
are  very  short-lived  men:  acute 
fevers,  and  gangrene  on  the  slightest 
accident,  carry  them  off  in  a  fright- 
ful manner.  Unfortunately  the 
dwellers  in  the  neighbourhood  also 
are  subject  to  the  same  action,  and 
the  mortality  from  these  causes  is 
very  great. 

The  action  of  the  *poudrette' 
upon  agriculture  is  somewhat  ex- 
traordinary. In  the  time  of  Henri 
Quatre,  the  wines  of  Suresnes  were 
highly  esteemed:  the  vines  pro- 
duced little,  but  of  a  superior 
quality:  since  the  poudrette  has 
been  used  to  force  them,  the  quan- 
tity of  their  produce  has  been  in- 
creased, but  the  quality  has  totally 
changed:  from  a  superior  rank,  the 
wines  of  the  neighbourhood  of  Paris 
have  fallen  to  that  of  what  is  vul- 
garly called  '  du  petit  bleu.' 

Fasnlf  a  mineral,  many  kinds  of  which 
are  peculiarly  and  elegantly  shaped 

FossiU/erous,  a  geological  term  ap- 
plied to  a  district  abounding  in 
fossils 

Foundations,  according  to  Palladio, 
ought  to  be  twice  as  thick  as  the 
walls  to  be  raised  upon  them,  so 
that  both  the  quality  of  the  earth 
and  the  greatness  of  the  building 
are  to  be  regarded,  making  the 
foundations  larger  in  a  soft  and 
loose  ground,  or  where  there  is  a 
great  weight  to  be  supported.  The 
plane  of  the  trench  must  be  as  level 
as  possible,  so  that  the  weight  may 
press  equally,  and  not  incline  more 
on  one  side  than  the  other,  which 
occasions  the  cleaving  of  the  walls. 


FOU 


FOUNDATIONS. 


FOU 


For  this  reason  the  ancients  were 
accustomed  to  pave  the  plane  with 
Tivertine ;  hut  we  most  commonly 
lay  planks  or  beams  to  haild  on. 
The  foundations  ought  to  he  made 
sloping,  that  is  to  say,  to  diminish 
as  they  rise;  but  yet  in  such  a' 
manner  that  the  middle  of  the  wall 
above  may  fall  plumb  with  the  mid- 
dle of  the  lowest  part ;  which  must 
be  also  observed  in  the  diminution 
of  walls  above  ground,  because  by 
that  means  the  building  becomes 
much  stronger  than  by  making  the 
diminution  any  other  way. 

Sometimes,    to    avoid   charges, 
(especially    in    marshy    grounds, 
where  there  is  a  necessity  to  use 
piles,)  foundations  are  arched  like 
a  bridge,  and  the  walls  are  built 
upon  those  arches.  In  great  build- 
ings it  is  very  proper   to  make 
vents  through  the  body  of   the 
walls  from  the  foundations  to  the 
roof,  because  they  let  forth  the 
irinds  and  other  vapours,  which 
are  very  prejudicial  to  buildings : 
they  lessen  the  charges,  and  are 
of  no    small   convenience,   espe- 
cially when  there  is  occasion  for 
winding-stairs  from  the  bottom  to 
the  top.     If  it  be  necessary  to 
construct    vaults    below    ground, 
their  foundations  must  be  more 
substantial  than  the  walls  of  the 
buildings  which  are  to  be  raised 
upon  them.     The  walls,  pillars, 
and  columns  of  the  latter  must 
be  placed  immediately  over  those 
below  them,  so  that  solid  may  bear 
upon  solid ;  for  if  walls  or  columns 
project  beyond  the  substructure, 
their  duration  must  necessarily  be 
short. 

The  value  of  concrete  in  founda- 
tions was  rendered  obvious  in  a 
building  erected  by  Mr.  Clegg  at 
Fulham,  in  1829.  The  foundation 
was  a  quicksand.  After  the  exca- 
vation was  got  out  to  the  depth  of 
15  feet,  an  iron  rod  sunk,  with 
little  more  than  its  own  weight, 
15  feet  more;  it  was,  in  fact,  as 
bad  a  foundation  as  could  possibly 

194 


occur.  In  about  twelve  days  after 
it  was  built,  it  had  settled  bodily 
down  16^  inches,  without  a  crack, 
or  deviating  in  the  least  from  the 
plumb.  It  therefore  follows,  that 
the  only  disadvantage  attend^g  a 
bad  natural  foundation  is  the  ex- 
pense of  making  an  artificial  one. 
The  following  extract  relates  to  the 
erection  of  an  extensive  building 
upon  bad  ground. 

'*The  building  for  the  Albion 
Mills  was  erected  upon  a  very  soft 
soil,  consisting  of  the  *made  ground' 
at  the  abutment   of  Blackfriars' 
Bridge:  to  avoid  the  danger  of 
settlement  in  the  walls,  or  the  ne- 
cessity of  going  to  a  very  unusual 
depth  with  the  foundations,  Mr. 
R^nie  adopted  the  plan  of  forming 
inverted  arches  upon  the  ground 
over  the  whole  space  upon  which 
the  building  was  to  stand,  and  for 
the  bottom  of  the  dock.    For  this 
purpose  the  ground  upon  which  all 
the  several  walls  were  to  be  erected 
was  rendered  as  solid  as  is  usual 
for  building  by  driving  piles  where 
necessary,  and  then  several  courses 
of  large  flat  stones  were  laid  to 
form  the  foundations  of  the  several 
walls ;  but  to  prevent  any  chance 
of  these  foundations  being  pressed 
down  in  case  of  the  soft  earth 
yielding  to  the  incumbent  weight, 
strong  inverted  arches  were  built 
upon  the  ground  between  the  foun- 
dation courses  of  all  the  walls,  so 
as  to  cover  the  whole  surface  in- 
cluded between  the  walls ;  and  the 
abutments  or  springings  of  the  in- 
verted arches  being  built  solid  into 
the  lowercourses  of  thefoundations, 
they  could  not  ihik  unless  all  the 
ground  beneath  the  arches  had 
yielded  to  compression,  as  well  as 
the  ground  immediately  beneath  the 
foundation  of  the  walls.    By  this 
method  the  foundations  of  all  the 
walk  werf  joined  together  so  as  to 
form  one  immensebase,which  would 
have  been  very  capable  of  bearing 
the  required  weight,  even  if  the 
ground  had  been  of  the  consistency 


FOU 


FOUNDATIONS. 


FRA 


of  mud;  for  the  whole  building 
would  have  floated  upon  it  as  a 
ship  floats  in  water ;  and  whateyer 
sinking  might  have  taken  place, 
would  have  affected  the  whole 
building  equally,  so  as  to  have 
avoided  any  partial  depressions  or 
derangement  of  the  walls ;  but  the 
ground  being  made  tolerably  hard, 
in  addition  to  this  expedient  of 
augmenting  the  bases  by  inverted 
arches,  the  building  stood  quite 
firm." 

When  the  foundation  has  been 
properly  disposed  of,  the  brickwork 
may  be  commenced.     The  bricks 
should  be  well  burned,  and  set  with 
a  thin  joint,  four  courses  not  occu- 
pying more  depth  than  11}  inches. 
Fowndations  of  Temples,  In  preparing 
fbundations  for  works  of  this  kind, 
it  will  be  first  necessary  to  dig  down 
to  a  regular  stratum,  if  such  is  to 
be  met  with;  and  upon  this  the 
foundations,  constructed  with  great 
attention  to  their  strength,  are  to 
be  laid:  their  soUdity  must  be  pro- 
portioned to  the  magnitude  of  the 
building  in  contemplation.     The 
piers  above  ground,  below  the  co- 
lumns, should  be  thicker  than  the 
diameter  of  the  columns  they  are 
to  support  by  one*half,  that  these 
substructures,  which  are  called  ste- 
reobatse,  on  account  of  their  sus- 
taining the  whole  weight,  may  be 
enabled  by  their  greater  solidity  to 
support  what  is  built  upon  them. 
The  bases  of  the  columns,  when 
fixed,  ought  not  to  project  before 
the  face  of  the  stereobatse  on  either 
side.     The  intervals  between  the 
piers  should  either  be  made  solid 
by  means  of  piles,  or  arched  over, 
so  as  to  connect  the  piers. 

If  no  compact  stratum  is  to  be 
found,  but  the  ground,  on  the  con- 
trary, is  loose  or  marshy  to  a  great 
depth,  trenches  must  be  dug,  and 
piles  of  chaired  alder,  olive,  or  oak, 
placed  close  together,  be  driven  in 
by  means  of  machines :  the  inter- 
vals between  them  should  be  filled 
I      up  with  charred  timber,  and  upon 

195 


this  substratum  the  foundations 
should  be  formed  with  solid  ma- 
sonry. Thefoundationsbeingreared 
to  the  same  level  all  around,  the 
stylobate  is  next  to  be  constructed. 
Upon  this  the  columns  are  to  be 
arranged,  in  the  manner  already 
described,  at  intervals  which  arc 
determined  by  the  species  of  temple 
intended  to  be  built,  whether  pyc- 
nostyle,  systyle,  diastyle,  or  eustyle. 
In  the  araeostyle  species  the  co- 
lumns may  be  placed  at  any  dis- 
tance asunder. 

Foundatioru  of  a  Bridge :  these  con- 
sist, properly,  of  the  undergroun<l 
work  of  the  piers  and  abutments, 
which  it  is  within  the  province  of 
a  civil  engineer  to  construct :  the 
necessity  of  firmness  and  solidity 
in  the  execution  of  such  works 
will  be  deemed  of  importance  just 
in  proportion  to  the  intended  ex- 
tent and  magnificence  of  the  struc- 
ture they  are  designed  to  support 

Foundry^  a  place  where  masses  of 
metal  are  melted  and  run  into 
moulds,  so  as  to  assume  the  re- 
quired form 

Four-way-cockf  a  cock  having  two 
separate  passages  in  the  plug,  and 
communicating  with  four  pipes 

Fox-taU  wedging^  in  carpentry.  This 
is  done  by  sticking  into  the  point 
of  a  wooden  bolt  a  thin  wedge  of 
hard  wood,  which,  when  the  bolt 
reaches  the  bottom  of  the  hole, 
splits,  expands,  and  secures  it. 

Frame^  the  strong  frame-work,  out- 
side the  wheels,  which  supports  the 
boiler  and  machinery  on  the  axles 
of  a  locomotive  engine 

FrariMy  vmde,  in  locomotive  engines. 
'  Some  engines  have  the  supporting 
frames  within  the  wheels,  and  are 
called  vaside-fratned  engines.  Be- 
sides this  frame,  resting  on  the 
axles,  there  are  also  other  strong 
stays  from  the  fire-box  to  the 
smoke-box,  called  inride  framing  \ 
or  ttays^  iot  supporting  the  worksj 
and  strengthening  the  boiler. 

Framesy  the  bends  of  timbers  that  are] 
bolted  together :  in  small  ships  there 


FRA 


FRESCO. 


FRI 


are  two  bolts  in  every  shift  of  tim- 
ber, and  three  in  large  ships.  The 
bolts  should  be  disposed  clear  of 
the  chain  and  preventer- bolts, 
scapper,  lodging  knee -bolts,  and 
port  cells. 

Frankfort-black  is  said  to  be  made  of 
the  lees  of  wine  from  which  the 
tartar  has  been  washed,  by  burning 
in  the  manner  of  ivory-black.  Fine 
Frankfort-black,though  almost  con- 
fined  to  copper-plate  printing,  is 
one  of  the  best  black  pigments  we 
possess,  being  of  a  fine  neutral 
colour,  next  in  intensity  to  lamp- 
black, and  more  powerfd  than  that 
of  ivory. 

Frater-house,  the  refectory  or  hall  of 
a  monastic  establishment 

Fredsiole,  a  seat  near  the  altar 

Freedom,  in  drawing,  is  a  bold  and 
spirited  manner,  with  evident  li- 
berty of  the  pencil ;  t.  e,  where  the 
drawing  is  apparently  accomplish- 
ed with  ease 

Freemason,  as  applied  to  ancient  ar- 
chitecture :  a  person  learned  in  the 
art  of  building,  more  particularly 
in  ecclesiastical  construction,  and 
who,  by  his  learning  in  the  science 
and  his  taste  in  constructions  of 
edifices,  travelled  from  one  country 
to  another,  and  executed  models  of 
everlasting  renown.  The  term  may 
also  be  applied  to  a  free-stone 
mason,  or  a  cutter  and  worker  in 
stone,  without  reference  to  the  so- 
ciety called  Freemasons. 

Freestone,  building  stone  which  may 
be  easily  cut  into  blocks  and  worked 
with  a  chisel;  so  called  from  having 
no  grain :  it  may  therefore  be  cut 
in  any  direction 

Free-stuff,  that  timber  or  stuff  which 
is  quite  clean  or  without  knots, 
and  works  easily,  without  tearing 

French  chalk  is  an  indurated  mag- 
nesian  mineral,  employed  to  remove 
grease  stains 

French  School  qf  Painting.  This 
school  has  been  so  different  under 
different  masters,  that  it  is  difficult 
to  characterize  it.  Some  of  its 
artists  have  been  formed  on  the 

196 


Florentine   and    Lombard    styles, 
others  on  the  Roman,  others   on 
the  Venetian,  and  a  few  of  them 
have  distinguished  themselves  by  a 
style  which  may  be  called  their  own. 
In  speaking  in  general  terms  of  this 
school,  it  appears  to  have  no  pe- 
culiar character,  and  can  only  ))e 
distinguished  by  its   aptitude   to 
imitate  easily  any  impressions;  and 
it  may  be  added,  speaking  still  in 
general  terms,  that  it  unites  in  a 
moderate  degree  the  different  parts 
of  the  art,  without  excelling  in  any 
one  of  them. 
Fresco,  a  kind  of  painting  performed 
on  fresh  plaster,  or  on  awall  covered 
with  mortar  not  quite  dry,  and  with 
water  colours.    The  plaster  is  only 
to  be  laid  on  as  the  painting  pro- 
ceeds, no  more  being  done  at  once 
than  the  painter  can  despatch  in  a 
day.    The  colours,  being  prepared 
with  water,  and  applied  over  plaster 
quite  fresh,  become  incorporated 
with  the  plaster,  and  retain  their 
beauty  for  a  great  length  of  time. 
The  Romans  cut  out  plaster  paint- 
ings  on  brickwalls  at  Sparta, packed 
them  up  in  wooden  cases,  and  trans- 
ported them  to  Rome. 
Fret,  an  ornament  used  in  classical 
architecture,  formed  by  small  fil- 
lets intersecting  each  other  at  right 
angles 
Friars  (the  orders  of)  in  England  and 
Wales,  previous  to  their  abolition, 
including  the   Nuns   Minoresses, 
amounted  to — 

Black  or  Dominican  friars .  54 
Grey  or  Franciscan  friars  .  62 
Minoresses  or  nuns  of  the 

order  of  St.  Clare  ...      4 
Friars  of  the  order  of  the 
Holy  Trinity  for  the  re- 
demption of  captives .    .     12 
Order  of  the  CarmeUtes  or 

White  friars     ....    50 
Crutched  or  Crossed  friars    10 

Austin  friars 32 

Friars  de  poenitentia  or  of 

the  sac 9 

Bethlemite  friars      ...      6 
Friction,  the  act  of  rubbing  two  bodies 


FRI 


FURNACE. 


FUR 


together,  or  the  resistance  in  ma- 
chines caused  by  the  contact  of 
different  moving  parts.  Friction  is 
proportional  to  the  pressure ;  that 
is,  every  thing  remaining  the  samCi 
the  friction  increases  as  the  pres- 
sure increases. 

Friction^lutch,  a  shell  or  box  fixed 
on  the  end  of  a  driving  shaft,  fitted 
by  a  conical  piece  which  slides  on 
a  feather,  or  raised  part,  at  the  end 
of  another  shaft,  so  that  it  can  be 
engaged  at  pleasure  by  the  cone 
being  forced  into  the  shell  by  a 
lever  or  screw.  This  apparatus  is 
very  useful  for  driving  machines, 
the  parts  of  which  are  subjected  to 
violent  strains,  as  the  pressure  upon 
the  clutch  can  be  regulated  so  as 
to  allow  it  to  slide  when  the  strain 
is  too  great  to  be  borne  safely  by 
the  machine. 

Frieze,  the  middle  division  of  an  en- 
tablature, that  which  lies  between 
the  architrave  and  the  cornice 

Prigidarium,  the  cold  bathing-room 
in  the  baths  of  the  ancients,  as  well 
as  the  vessel  in  which  the  cold  water 
was  received 

Frigidarium,  the  cold  bath :  the  re- 
servoir of  cold  water  in  the  hjrpo- 
caustum,  or  stove-room,  was  termed 
ahenum  frigidarium 

Frithstool  ox  Freedgtool,  a  seat  or 
chair  near  the  altar,  for  those  espe- 
cially who  sought  the  privilege  of 
sanctuary 

Frontal  or  Fronter,  the  hanging  with 
which  the  front  of  an  altar  was 
formerly  covered 

Fronton,  a  French  word  to  express 
an  ornament  over  a  door  or  pedi- 
ment 

Frowy  stuff,  short  or  brittle  and  soft 
timber 

Fucus,  a  name  given  by  the  Romans 
to  certain  false  dyes  and  paints 

Fuel,  the  matter  or  aliment  of  fire 

Fulcrum,  the  prop  or  support  by  which 
a  lever  is  sustained 

Fullers' 'Carth,  a  soft  unctuous  marl, 
used  by  fullers  in  the  process  of 
cleansing  cloth,  &c. 

FulUnff-mill,  an  engine,  or  mill,  in 

197 


which  cloth  is  cleansed  by  being 
beaten  with  hammers 

FtHminatinff  gold  or  tUifer,  in  che- 
mistry, ammonia  combined  with 
the  oxides  of  gold  or  silver 

Fumarium,  a  chimney ;  an  upper 
room  used  among  the  Romans  for 
collecting  the  smoke  from  the 
lower  apartments:  used  also  for 
smoking  or  ripening  wines 

Furling,  in  navigation,  the  wrapping 
up  and  binding  of  any  sail  close  to 
the  yard 

Furlong,  a  measure  of  length;  the 
eighth  part  of  a  mile 

Furnace.  The  furnace  is  one  of  the 
most  important  parts  of  the  high- 
pressure  engine.  The  whole  action 
and  power  of  the  machine  depend 
on  its  construction,  and  on  the 
efifect  obtained  from  it,  inasmuch 
as  fire  is  the  prime  agent.  Too 
much  industry,  exactitude,  and  in- 
timate knowledge  of  the  subject, 
cannot  be  brought  to  bear  on  the 
construction  of  the  furnace,  in  order 
to  attain  the  two  great  objects  of 
its  action;  namely,  first,  to  produce 
as  perfect  a  combustion  of  the  fuel 
as  possible ;  and  secondly,  to  apply 
as  much  as  possible  of  the  heat  so 
developed  effectively  to  the  boiler. 
These  two  requirements  for  a  good 
furnace  are,  however,  not  so  easily 
satisfied.  Much  remains  to  be  ac- 
quired as  to  the  conditions  under 
which  the  whole  of  the  caloric  may 
be  perfectly  developed  from  the  fuel, 
although  the  best  manner  of  apply- 
ing the  heat  to  the  boiler  is  well 
understood. 

Furniture :  anterior  to  the  Tudor  age, 
household  furniture  was  in  general 
of  a  rude,  substantial  character; 
the  tables  were  formed  of  boards 
or  trestles,  the  seats  of  massive  oak 
benches  or  stools,  and  the  floors 
strewed  with  straw 

Furniture  of  the  hall:  this  consisted 
of  but  few  articles,  such  as  clumsy 
oak  tables  covered  with  carpet, 
benches  or  joined  forms  of  the  same 
material,  and  cupboards  for  plate, 
pewter,  Hreene,'  leather  jugs,  glass. 


FUR 


GALLERY. 


FUT 


&c.,  with  a  reredos  or  fire-iron  in 
the  centre  of  the  floor,  against  which 
fagots  were  piled  and  burned,  the 
smoke  passing  through  an  aperture 
in  the  roof;  the  fender,  formed  by 
a  raised  rim  of  stone  or  tile,  and  a 
'  fier  forke'  and  tongs 

FurrmgSf  slips  of  timber  nailed  to 
joists  or  rafters,  in  order  to  bring 
them  to  a  level,  and  to  range  them 
into  a  straight  surface,  when  the 
timbersare  8agged,either  by  casting, 
or  by  a  set  which  they  have  ob- 
tained by  their  weight  in  the  course 
of  time 

Fuaarokf  in  architecture,  a  moulding 
or  ornament  placed  immediately 
under  the  echinus  in  the  Doric, 
Ionic,  and  Composite  capitals ;  the 
shaft  of  a  column,  pilaster  or  pillar, 
or  that  part  comprehended  between 
the  shaft  and  the  capital 


GAB 

Gable,  the  upright  triangular  end  of 
a  house,  from  the  cornice  or  eaves 
to  the  top  of  the  building,  some- 
times called  a  sloped  roof;  the  up- 
per part  of  a  wall,  above  the  level 
of  the  eaves.  Examples  in  English 
and  foreign  Domestic  and  Gothic 
architecture  are  various,  and  gene- 
rally have  a  most  picturesque  effect. 

Gablettf  small  ornamental  gables  or 
canopies  formed  over  tabernacles, 
niches,  &c. 

Gajff^,  a  sort  of  boom  used  in  small 
ships  to  extend  the  upper  edge  of 
the  mizen,  and  employed  for  the 
same  purpose  on  those  sails  whose 
foremost  edges  are  joined  to  the 
masts  by  hoops  or  lacings,  and 
which  are  usually  extended  by  a 
boom  below:  such  are  the  main- 
sails  of  sloops,  brigs,  and  schooners 

Gage  or  Gauge,  an  instrument  used  for 
measuring  the  state  of  rarefaction  in 
the  air-pump,  variations  in  the  baro- 
meter, &c. ;  a  measure,  a  standard 

Gal,  in  Cornish,  rusty  iron  ore 

GaUlee,  a  porch  or  chapel  at  the  en- 
trance of  a  church.  The  galilee  at 
Lincoln  cathedral  is  a  porch  on  the 

T98 


Fustic,  a  wood  of  a  species  of  miil- 
berry  growing  in  most  parts  of 
South  America,  the  United  States, 
and  the  West  Indies :  it  is  a  large 
and  handsome  tree,  principally  used 
for  dyeing  greens  and  yellows,  and 
'  also  in  mosaic  cabinet-work  and 
turnery 

Futtock,  in  ship-building.  Every 
single  timber  is  called  a  futtock, 
and  distinguished  by  the  terms 
lower,  or  first,  second,  third,  &c., 
except  the  floors,  long  and  half- 
timbers,  top  timbers,  stern  tim- 
bers, &c. 

Futiocka,  the  lower  timbers  raised 
over  the  keel,  and  which  hold  the 
ship  together 

Futtock  shrouds,  in  ship  rigging,  small 
shrouds  that  go  from  the  main- 
roast,  fore-mast,  and  mizen-mast 
shrouds  to  those  of  the  top-mast 


GAL 

west  side  of  the  south  transept :  at 
Ely  cathedral  it  is  a  porch  at  the 
west  end  of  the  nave :  at  Durham 
it  is  a  large  chapel  at  the  west  end 
of  the  nave,  which  was  built  for  the 
use  of  the  women,  who  were  not 
allowed  to  advance  further  into  the 
church  than  the  second  pillar  of 
the  nave. 

Gallery,  an  apartment  generally  of 
greater  length  in  proportion  to  the 
width,  applied  for  the  purpose  of 
exhibiting  pictures  or  sculpture: 
used  formerly  in  early  English  Do- 
mestic architecture,  in  large  houses, 
as  a  place  of  resort  for  damicing  and 
other  amusements 

Galliot,  a  Dutch  vessel,  carrying  a 
main  and  a  mizen  mast,  and  a  Isurge 
gaff  main-sail 

Gall-stone  (colour),  an  animal  calcu- 
lus formed  in  the  gall-bladder, 
principally  of  oxen.  This  concre- 
tion varies  a  little  in  colour,  but  is 
in  general  of  a  beautiful  golden 
yellow,  more  powerful  than  gam- 
boge, and  is  highly  reputed  as  a 
water  colour :  nevertheless,  its  co- 
lour is  soon  changed  and  destroyed 


GAL 


GARDEN. 


GAR 


by  strong  light,  though  not  subject 
to  alteration  by  impure  air. 
Gahaniam  comprises  all  those  elec- 
trical phenomena  arising  from  the 
chemical  agency  of  certain  metals 
with  different  fluids 
Galvanometer,    an  instrument  con- 
trived to  measure  minute  quanti- 
ties of  electricity 
Gamboge,  or,  as  it  is  variously  written, 
Gumboge,     Gambouge,    Cambogiai 
Gambadium,  &c.,  is  brought  from 
Cambaja,  in  India,  and  is  the  pro- 
duce of  several  kinds  of  trees.    It 
is,  however,  principally  obtained 
from  the  tree  called  Gokathu,  which 
grows  in  Ceylon  and  Siam.     From 
the   wounded   leaves   and  young 
shoots  the  gamboge  is  collected  in 
a  liquid  state,  and  dried.    Gam- 
boge is  a  concrete  vegetable  sub- 
stance, of  a  gum^resinous  nature, 
and  beautiful  yellow  colour,  bright 
and  transparent,  but  not  of  a  great 
depth.     When  properly  used,  it  is 
more  durable  than  generally  re- 
puted, both  in  water  and  oil,  and 
conduces,  when  mixed  with  other 
colours,  to  their  stability  and  dura- 
bility, by  means  of  its  gum  and 
resin.     It  is  deepened  in  some  de- 
gree by  ammoniacal  and  impure 
air,  and  somewhat  weakened,  but 
not  easily  discoloured,  by  the  ac- 
tion of  Ught. 
Gammoning,  in  navigation,  seven  or 
eight  turns  of  a  rope  passed  over 
the  bowsprit,  and  through  a  large 
hole  in  the  stem  or  knee  of  the 
head,  alternately,  and  serving  to 
bind  the  inner  quarter  of  the  bow- 
sprit close  down  to  the  ship's  stem, 
in  order  to  enable  it  the  better  to 
support  the  stays  of  the  fore-mast: 
after  all  the  turns  are  drawn  as 
firm  as  possible,  the  opposite  ones 
are  braced  together  under  the  bow- 
sprit by  a  frapping 
Gammoning-hole,  a  hole  cut  through 
the  knee  of  the  head,  and  some- 
times one  under  the  standard  in 
the  head,  for  the  use  of  gammon- 
ing the  bowsprit 
Garboard  utrake,  the  strake  in  the 

199 


bottom  that  is  wrought  into  the 
rabbet  of  the  keel  of  a  ship 

Gardent.  .  The  ancient  plans  of  gar- 
dens show  that  the  Egyptians  were 
not  less  fond  than  our  ancestors  of 
mathematical  figures,  of  straight 
walks,  architectural  decorations, 
and  vegetable  avenues;  and  that 
they  as  thoroughly  entered  into 
the  idea  of  seclusion  and  safety 
suggested  by  enclosures  vrithin  en- 
closures. "It  has  been  remarked, 
that  in  some  old  EngUsh  places 
there  were  almost  as  many  walled 
compartments  vrithout  as  apart- 
ments within  doors :  the  same  may 
be  said  of  Egyptian  country  houses. 
This  principle  of  seclusion,  and  an 
excessive  love  of  uniform  arrange- 
ment, are  remarkably  displayed  in 
the  plan  of  a  large  square  garden 
given  in  Professor  Rosellini's  great 
work. 

As  a  subject  for  the  painter,  the 
materials  which  form  the  scenery 
of  a  garden  are  provided  by  Nature 
herself:  the  artist  must  therefore 
be  satisfied  with  the  degree  of  ex- 
pression which  she  has  bestowed, 
and  give  the  best  possible  disposi- 
tion to  those  scanty  and  intractable 
materials.  In  a  landscape,  on  the 
contrary,  the  painter  has  the  choice 
of  the  objects  he  intends  to  repre- 
sent, and  can  give  whatever  force 
or  extent  he  pleases  to  the  expres- 
sion he  wishes  to  convey,  as  the 
whole  range  of  scenery  is  before 
his  eye. 

Gargoyle  or  Gvrgoyle,  a  projecting 
spout  used  in  Gothic  architecture, 
to  throw  the  water  from  the  gutter 
of  a  building  off  the  wall 

Garland,  an  ornamental  band  used  in 
Gothic  work 

Garnet,  a  hinge,  now  called  a  '  cross 
garnet ;'  a  red  gem  of  various  sizes 

Garret,  an  upper  apartment  of  a 
house,  immediately  under  the  roof 

Garrettmg,  small  splinters  of  stone 
inserted  in  the  joints  of  coarse 
masonry :  they  are  stuck  in  after 
the  work  is  built :  flint  walls  are 
very  frequently  garretted 


GAS 


GAS. 


GAS 


Gas.  All  substances,  whether  animal, 
vegetable,  or  mineral,  consisting  of 
carbon,  hydrogen,  and  oxygen, 
when  exposed  to  a  red  heat,  pro- 
dace  various  inflammable  elastic 
fluids  capable  of  furnishing  artificial 
light.  The  evolution  of  this  elastic 
fluid  may  be  perceived  during  the 
combustion  of  coalin  a  common  fire. 
The  coal,  when  heated  to  a  certain 
degree,  swells  and  kindles,  and 
frequently  emits  remarkably  bright 
streams  of  flame,  and  after  a  cer- 
tain period  these  appearances  cease, 
and  the  coal  glows  with  a  red  light. 

The  flame  produced  from  coal, 
oil,  wax,  tallow,  or  other  bodies 
which  are  composed  of  carbon  and 
hydrogen,  proceeds  from  the  pro- 
duction of  carburetted  hydrogen 
gas,  evolved  from  the  combustible 
body  when  in  an  ignited  state. 

If  coal,  instead  of  being  burnt 
in  the  ordinary  way,  be  submitted 
to  the  temperature  of  ignition  in 
close  vessels,  all  its  immediate  con- 
stituent parts  may  be  collected: 
the  bituminous  part  is  distilled 
over,  in  the  form  of  coal-tar,  &c., 
and  a  large  quantity  of  an  aqueous 
fluid  is  disengaged  at  the  same 
time,  mixed  with  a  portion  of  es- 
sential oil  and  various  ammoniacal 
salts.  A  large  quantity  of  carbu- 
retted hydrogen,  carbonic  oxide, 
carbonic  add,  and  sulphuretted 
hydrogen,  also  make  their  appear- 
ance, together  with  small  quantities 
of  cyanogen,  nitrogen,  and  free 
hydrogen,  and  the  fixed  base  of  the 
coal  idone  remains  behind  in  the 
distillatory  apparatus,  in  the  form 
of  a  carbonaceous  substance  called 
coke.  An  analysis  of  the  coal  is 
effected  by  the  process  of  destruct- 
ive distiUation ;  and  the  products 
which  the  coal  furnishes  may  be 
separately  collected  in  different 
vessels. 

The  carburetted  hydrogen,  or 
coal-gas,  when  freed  firom  the  ob- 
noxious foreign  gases,  may  be  pro- 
pelled in  streams  out  of  small 
apertures,   which,   when  lighted, 

200  ~~" 


form  jets  of  flame,  now  called  fftu- 
lights. 

Mr.  Croll  has  patented  an   in- 
vention for  the  purification  of  gas 
from  ammonia,  which  is  effected 
by  means  of  dilute  sulphuric  acid 
applied  between    the   condensers 
and  the   ordinary  lime  purifiers. 
The  vessels  are  made  either  of  wood 
or  iron,  and  lined  with  lead,  having 
a  wash-plate  similar  to  the  wet-lime 
purifiers.    The  radiating  bottom  is 
formed  of  wooden  bars,  for  the  pur- 
pose of  supporting  the  wash-plate 
and  distributing  the  gas.    In  com- 
mencing the  process,  these  vessels 
are  charged  with  water  and  sulphu- 
ric acid  in  the  proportion  of  7  fbs. 
of  the  latter  to  100  gallons  of  the 
former.    As  the  add  is  neutralized 
by  the  ammonia  contained  in  the 
gas  passing  through  the  vessels, 
the  above  proportion  is  kept  up  by 
a  continuous  dropping  or  running 
of  add,  regulated  according  to  the 
quantity  of  ammonia  contained  in 
the  gas,  from  a  reservoir  placed  on 
the  top  of  the  saturator.      This 
mode  of  supplying  the  add  is  con- 
tinued until  the  specific  gravity  of 
the  solution  is  at  1170,  or  near  the 
point  of  crystallization ;  after  which 
the  supply  of  add  is  discontinued, 
and  the  liquor  retained  in  the  vessel 
until  neutralized :  it  is  then  drawn 
off  and  evaporated,  and  yidds  a 
pure  sulphate  of  ammonia. 
Gas  (distribution  of,  through  mams). 
There  is  no  branch  of  sdence  con- 
nected with  the  subject  of  gas  en- 
gineering so  highly  important  as 
that  which  relates  to  its  conveyance 
and   distribution   through  pipes; 
there  is  none  in  which  theory  af- 
fords more  assistance,  and  there  is 
hardly  any  branch  to  which  so  lit- 
tle attention  has  been  paid.    The 
interests  of  a  gas  company  are  not 
best  served  by  simply  increasing 
the  quantity  of  gas  from  the  same 
quantity  of  coal,  or  improving  the 
lime  machinery,  &c.  The  laying  of 
street-mains  forms  the  most  consi- 
derable item  in  the  outlay;  and  by 


GAS 


GAS  DISTRIBUTION. 


GAS 


a  jadidous  arrangement  in  the  first 
instance,  much  may  be  saved  both 
at  first  and  last. 

It  is  for  the  purpose  of  rendering 
this  branch  of  the  science,  and  that 
of  the  passage  of  gas  through  pipes, 
perfectly  plain,  that  the  following 
observations  are  here  given. 

When  it  is  proposed  to  light  any 
town,  or  district  of  a  town,  with 
gas,  the  first  step  to  be  taken  is  to 
ascertain  the  number   of  lights, 
both  public  and  private,  that  will 
be  required,  with  as  much  accu- 
racy as  circumstances  will  permit ; 
the  length  of  time  such  lights  vrill 
have  to  bum,  and  the  quantity  of 
gas  consumed  by  them  per  hour, 
making  allowances  for  the  increase 
of  lamps  that  will  probably  be  re- 
quired by  the  extension  of  the  town. 
The  size  of  the  works  themselves 
may  be  easily  ascertained  from  this 
calculation.     It  will  then  remain 
to  fix  upon  a  proper  situation  in 
which  to  erect  them :  the  best  local 
position  is  upon  the  banks  of  a  na- 
vigable river  or  canal,  and  at  the 
lowest  available  level,  and  the  near- 
est approach  to  such  a  situation  is 
advisable  for  obvious  reasons.    A 
map  of  the  town  must  be  obtained, 
or  a  survey  made  of  the  different 
streets  and  thoroughfares :  running 
levels  must  be  taken  through  them 
at  several  points,  and  their  respect- 
ive heights  marked  with  reference 
to  the  level  of  the  works  as  a  da- 
tum :  upon  this  map  all  the  mains 
must  be  drawn,  also  their  branches, 
valves,  and  governors.    Their  ar- 
rangement must  be  such  as  to  allow 
of  a  perfect  circulation  of  the  gas, 
and  a  nearly  uniform  pressure  at 
the  highest  and  lowest  point.     All 
the  pipes    upon    the  same  level 
should  be  joined  into  one  another, 
and  no  valves  used  but  such  as  are 
necessary  to  shut  off  the  gas  for 
repair  of  mains.  To  supply  a  higher 
level,  a  governor  should  be  placed 
at  the  summit  of  the  lower  level, 
with  the  lower  main  leading  into 

it.  The  pipe  or  pipes  for  supplying 
__ 


the  higher  parts  should  proceed 
from  the  regulating  vessel.  A  cel- 
lar may  be  appropriated  for  the 
reception  of  this  vessel.  One  lead- 
ing main  should  be  taken  direct 
from  the  works  to  an  equilibrium 
cylinder  situated  at  some  point 
from  which  several  streets  diverge, 
and  no  supply  taken  from  this  main 
until  it  has  reached  the  cylinder. 
Branches  suitable  to  the  supply 
of  each  division  of  the  district 
should  lead  from  this  cylinder. 
The  supply  of  gas  to  the  cylinder 
should  be  so  regulated  as  to  cause 
the  gas  to  flow  along  the  branches 
at  an  even  pressure  of  about  five- 
tenths  of  an  inch.  If  the  cylinder 
be  at  any  considerable  distance 
from  the  works,  a  smaller  main, 
vrith  increased  pressure,  may  lead 
to  it,  its  size  being  sufficient  to 
equalize  the  discharge. 

Supposing  a  district  to  be  lighted 
requiring  1000  public  or  street 
lamps,  and  7000  private  burners : 
it  is  usually  considered  that  each 
lamp  on  an  average  will  consume 
5  cubic  feet  of  gas  per  hour,  there- 
fore 40,000  cubic  feet  \rill  be  re- 
quired to  light  the  district  for  an 
hour ;  and  the  leading  main  must 
be  capable  of  delivering  that  quan- 
tity into  the  equilibrium  cylinder 
in  that  time.  To  determine  the 
size  of  this  main,  the  probable  in- 
crease of  lamps  must  be  taken  into 
consideration ;  and  as  that  will  de- 
pend so  much  upon  circumstances 
in  every  instance,  the  judgment  of 
the  engineer  alone  can  serve  to  re- 
gulate the  additional  area.  If  the 
increase  should  be  beyond  that 
which  was  expected,  the  gas  mast 
be  forced  through  the  leading  main 
at  a  greater  pressure. 

In  the  above  example,  if  the 
diameter  of  main  for  a  present  con- 
sumption be  12  inches,  and  to  se- 
cure an  adequate  supply  at  any 
future  period  its  diameter  be  in- 
creased to  15  inches,  the  present 
working  pressure  may  be  reduced 
to  1*5  of  an  inch  instead  of  3  inches;  | 


Id 


GAS 


GATES  AND  DOORS. 


GAT 


and  as  the  leakage  will  also  be 
decreased,  the  extra-sized  main 
will  not  be  found  disadvantageous 
even  in  the  first  instance. 

Goiometer,  a  reservoir  of  gas,  with 
conveniences  for  measuring  its 
volume.  The  simplest  and  most 
general  in  use  consists  of  an  iron 
vessel,  open  at  the  bottom,  and 
inverted  into  a  tank  of  water  below 
the  surface  of  the  ground,  having 
perfect  freedom  to  rise  and  fall, 
and  guided  by  upright  rods  fixed  at 
several  points  in  the  circumference. 
The  diameters  and  numbers  of  the 
vessels  will  vary  according  to  the 
magnitude  of  the  works  to  which  the 
gasometer  is  attached,  and  the  space 
to  be  occupied  by  it.  If  the  works 
are  situated  in  a  town,  where  the 
ground  is  too  valuable  to  allow  an 
increased  extent,  a  *  telescope  gaso- 
meter' is  employed. 

Gas-tarf  commonly  called  coaUtar, 
When  the  manufacture  of  gas 
from  coal  was  in  its  infancy,  great 
advantages  were  expected  to  be 
derived  from  the  coal-tar  which 
distilled  over  with  the  inflammable 
gas.  It  was  considered  to  be  a 
substance  possessing  even  superior 
properties  to  the  vegetable  tar  for 
the  preservation  of  timber  and  other 
perishable  materials  exposed  to  the 
influences  of  the  weather. 

In  the  year  1665  a  German 
chemist  proposed  to  distil  coal  for 
the  sole  purpose  of  obtaining  this 
tar,  and  in  1781  the  Earl  of  Dun- 
donald  took  out  a  patent  for  col- 
lecting the  tar  which  appeared 
during  the  formation  of  coke.  Nei- 
ther scheme  answered.  After  a 
few  years'  trial,  coal-tar  as  a  sub- 
stitute for  vegetable  tar  fell  into 
disuse.  It  was  tried  in  the  navy, 
and  was  found  to  give  the  timber  a 
considerable  degree  of  hardness, 
but  not  of  durability.  Its  smell  is 
extremely  offensive ;  and  since  that 
time  it  has  been  used  only  in 
places  where  that  is  of  little  conse- 
quence. The  exposed  part  of  the 
machinery  of  a  gas  establishment 


may  be  protected  by  being  coated 
with  coal-tar. 

Gasketf  plaited  cord  fastened  to  the 
sail-yards  of  a  ship,  and  used  to 
furl  or  tie  up  a  sail  firmly  to  the 
yard,  by  wrapping  it  round  both  six 
or  seven  times,  the  turns  being  at  a 
competent  distance  from  each  other 

Gaichers,  the  after-leavings  of  tin 

Gate-house^  or  park  entrance,  a  struc- 
ture designed  rather  to  produce  an 
agreeable  and  picturesque  effect, 
than  to  accord  with  any  fixed  rules 
or  customs  of  art:  such,  indeed, 
was  the  practice  towards  the  latter 
end  of  the  sixteenth  century,  when 
it  would  appear,  that  most  men 
wished  to  display  their  taste  and 
learning  in  architecture.  The  gate- 
house flJso  forms  an  entrance  to  a 
private  mansion,  to  any  pubUc, 
municipal,  or  collegiate  building, 
or  to  a  palace,  &c.  In  the  early 
English  architecture,  gate-houses, 
now  sometimes  called  Lodges,  were 
large  and  imposing  structures,  of 
great  elegance. 

Gates  and  doors  are  generally,  whe- 
ther arched  or  square,  twice  their 
breadth  in  height.  The  former 
may  be  ornamented  with  columns, 
pilasters,  entablatures,  pediments, 
rustics,  imposts,  aichivolts,  &c; 
the  latter  with  architraves  round 
the  sides  and  top  of  the  opening, 
and  crowned  with  a  frieze  and  cor- 
nice. The  cornice  in  this  case  is 
very  frequently  supported  vrith  a 
console  on  each  side.  Columns, 
pilasters,  and  other  ornaments  are 
also  sometimes  employed  in  the 
decoration  of  doors. 

Inside  doors  should  not  be  nar- 
rower than  2  feet  9  inches,  nor  is 
it  needful  that  they  exceed  6  feet 
in  height ;  entrance  doors,  3  feet 
6  inches  to  6  feet  6  inches  broad 
in  private  dwellings :  but  in  public 
buildings,  where  crowds  assemble, 
they  must  be  considerably  enlarged. 
The  smallest  width  for  a  gate  should 
be  8  feet  6  inches. 

As  some  general  rule  for  the  pro- 
portion of  the  architraves  of  com- 


202 


r 


GAT 


GERMAN  SCHOOL. 


GER 


moa  dressings  to  doors  may  be 
iisefid,  the  foUowing  directions  may 
be  safely  followed :  Supposing  the 
height  of  the  aperture  to  represent 
the  height  of  a  column;  then,  if  an 
architrave,  frieze,  and  cornice,  or 
the  first  only,  be  desired,  take  them 
in  the  proportion  that  would  serve 
for  the  order  itself,  and  return  the 
architrave  down  the  sides  of  the 
door.  The  whole  entablature  over 
a  square-headed  door  should  never 
exceed  one-third  the  height  of  such 
aperture. 

Gauge  (pronounced  gagejt  a  measure 
by  which  the  capacity  or  contents 
of  a  cask  or  vessel  may  be  ascer- 
tained.  Gauging  is  a  term  used  in 
mensuration,  and  applied  by  engi- 
neers in  their  several  operations. 
The  gttuget  as  appUed  to  railways, 
became  a  familiar  term  during  the 
antagonistic  discussions  respecting 
the  proper  distance  between  the 
lines  of  rail ;  and  the  battie  of  the 
gauges,  which  raged  fiercely  and  ex- 
pensively, ended,  like  many  similar 
contentions,  in  both  parties  spend- 
ing enormous  sums  of  money,  with- 
out the  result  of  victory  on  either 
side. 

Gauge,  a  mixture  of  fine  stuff  and 
plaster,  or  putty  and  plaster,  or 
coarse  stuff  and  plaster;  used  in 
finishing  the  best  ceilings  and  for 
mouldings,  and  sometimes  for  set- 
ting walls 

Gauge-cocks,  two  or  three  small  cocks 
fixed  in  front  of  the  boiler  of  a  steam 
engine,  for  the  purpose  of  ascer- 
taining the  height  of  the  water 

Gauge-glass,  in  locomotive  engmes,  a 
strong  glass  tube,  connected  with 
the  boiler  by  two  cocks  attached 
to  the  gauge-cock  pedestal.  The 
water  is  admitted  to  this  tube  by 
the  lower  cock,  .the  steam  by  the 
upper  cock.  It  thus  becomes  an 
index  to  what  is  going  on  inside 
the  boiler,  exhibiting  the  height 
or  agitation  of  the  water  in  it.  A 
small  cock  is  placed  below  the 
glass  for  blowing  out  any  sediment 

which  may  be  deposited  in  it. 

— • — 

203 


Gauge-lan^,  in  locomotive  engines, 
a  small  lamp  placed  beside  the 
gauge-glass  at  night,  that  the  state 
of  the  water  in  the  boiler  may  be 
seen  by  the  engine-man 

Gauntlet,  in  heraldry,  an  iron  glove : 
in  challenges,  the  gauntlet  was 
thrown  down  in  defiance 

Gear,  furniture,  dress,  harness:  the 
term  is  also  applied  to  the  several 
working  parts  of  a  locomotive  steam 
engine 

Generating  surface,  the  heating  sur- 
face of  a  boiler,  or  that  on  which 
heat  is  applied  to  generate  steam 

Gentese,  in  early  English  architecture, 
cusps  or  featherings  in  the  arch  of 
a  doorway 

Geometry,  the  science  of  quantity, 
extension,  or  magnitude 

Geoscopy,  a  knowledge  of  the  different 
kinds  of  earth 

German  School  of  Painting,  In  early 
times,  a  school  of  painting  can 
hardly  be  said  to  have  existed  in 
Germany:  it  was  merely  a  suc- 
cession of  single  artists,  who  de- 
rived their  manner  from  different 
sources  of  originality  and  imitation. 
There  were  some  German  painters 
of  emimence  when  the  art,  emerg- 
ing from  its  barbarous  state,  first 
began  to  be  cultivated  in  Europe ; 
but  as  they  were  totally  unac- 
quainted with  the  ancients,  and  had 
scarcely  access  to  the  works  of  their 
contemporaries  in  Italy,  they  copied 
Nature  alone,  with  the  exception 
of  somewhat  of  that  stiffness  which 
forms  the  Gothic  manner.  This 
is  by  no  means  the  case  with  their 
successors,  some  of  whom  were  edu- 
cated in  Flanders,  and  others  in 
Italy.  But  if  Mengs  or  Dietrich 
were  comprehended  in  this  school, 
there  would  be  nothing  peculiar  to 
its  manner  discovered  in  their 
works.  Albert  Durer  was  the  first 
German  who  corrected  the  bad 
taste  of  his  countrymen :  he  ex- 
celled in  engraving  as  well  as  in 
painting ;  his  genius  was  fertile,  his 
compositions  varied,  his  thoughts 
ingenious,  and  his  colours  brilhant. 


GEO 


GIRDERS. 


GIR 


His  workSi  though  numerous,  were 
finished  with  great  exactness.  For 
an  account  of  this  great  man  and 
his  productions,  see  the  'Works  of 
DiYcrsAndentMasters/  in  two  vols. 
foUo,  1846. 

Geology  (a  treatise  or  discourse  on 
the  earth)  "is  a  term  which  admits 
of  a  very  wide  interpretation,  and 
naturally  suggests  to  the  mind  in- 
quiries,— 1st,  into  the  formation 
and  original  condition  of  the  earth; 
2ndly,  into  the  successive  modifica- 
tions which  it  has  undergone,  and 
the  agencies  by  which  they  have 
been  effected;  and  3rdly,  into  its 
present  condition,  and  the  agencies 
by  which  changes  in  that  condition 
are  still  effected.  The  first  object 
of  the  geologist  is  to  establish,  on 
the  principles  of  inductive  reason- 
ing, the  science  as  it  depends  on 
each  of  these  inquiries,  and  then  to 
apply  it  to  the  practical  purposes 
of  life.  It  may  be  premised  that  a 
science  is  practicably  valuable  just 
in  proportion  as  its  facts  have  been 
discovered,  and  its  laws  established 
and  studied ;  for  so  long  as  we  are 
uncertain  whether  a  known  result 
has  proceeded  from  a  definite  cause, 
we  are  unable  to  apply  the  fact  or 
circumstance  to  the  elucidation  of 
other  facts  or  circumstances;  and 
so  long  as  we  are  unacquainted 
with  the  properties  of  any  sub- 
stance under  our  examination,  we 
cannot  declare  with  certainty  what 
share  it  may  have  had  in  the  phe- 
nomena we  have  observed.  This 
may  be  illustrated  by  a  reference 
to  gunpowder.  Its  explosive  qua- 
lity is  the  result  of  its  composition, 
and  we  can  only  depend  upon  the 
results  when  we  know  that  the 
compound  has  been  accurately 
formed:  to  insure,  therefore,  cer- 
tainty in  the  operations  depending 
on  it,  we  must  take  care  that  a 
proper  standard  of  composition  has 
been  adhered  to.  In  a  similar  man- 

'  ner  we  can  only  apply  geology  as  a 
practical  science  when  we  have  as- 
certained and  made  ourselves  fami- 

204 


liar  with  those  facts  which  prove 
the  first  principles  on  which  it  has 
been  founded  to  be  correct  and 
stable.'' 

Gib  and  key^  the  fixed  wedge  and  the 
driving  wedge  for  tightening  the 
strap  which  holds  the  brasses  at 
the  end  of  a  connecting-rod  in 
steam  machinery 

Gimletf  a  piece  c^  steel  of  a  cylin- 
drical form,  having  a  transverse 
handle  at  the  upper  end,  and  at  the 
other,  a  worm  or  screw,  and  a  cy- 
lindric  cavity,  called  the  cup,  above 
the  screw,  forming,  in  its  trans- 
verse section,  a  crescent.  Its  use 
is  to  bore  small  holes :  the  screw 
draws  it  forward  in  -the  wood,  in 
the  act  of  boring,  while  it  is  turned 
round  by  the  handle:  the  angle 
formed  by  the  exterior  and  interior 
cylinders  cuts  the  fibres  across, 
and  the  cup  contains  the  core  of 
wood  so  cut :  the  gimlet  is  turned 
round  by  the  application  of  the 
fingers,  on  alternate  sides  of  the 
wooden  lever  at  the  top. 

Girders,  the  longitudinal  beams  in  a 
floor.  Girders  are  the  chief  sup- 
port of  a  framed  floor:  their  depth 
is  often  limited  by  the  size  of  the 
timber,  but  not  always  so ;  there- 
forethe  method  of  finding  the  scant- 
ling may  be  divided  into  more  than 
in  one  case.  Girders  of  wrought 
and  cast  iron  are  now  extensively 
used  for  bridges,  to  girt  railroads, 
canals,  &c.,  many  of  which  are  of 
considerable  span:  the  foUovring 
will  give  a  better  explanation  of 
the  importance  of  testing  their 
strength. 

'  Experiments  on  an  open  ca»t-iron 
girder, — ^Figures  1  and  2,  in  the  an- 
nexed diagrams,  show  the  eleva- 
tion and  section  of  a  cast-iron  open 
girder,  which  was  intended  to  act 
as  a  bressummer  between  the  co- 
lumns which  supported  aniron  sheet 
roof  of  40  feet  span.  These  columns 
were  20  feet  apart  from  centre  to 
centre,  and  the  principals  of  the 
roof  being  6  feet  8  inches  apart,  two 
of  them  were  of  course  supported 


G[R 

GIRDERS.                                             GIK  | 

hj  the  iron  girder  at  the  poiotg  a 

Kg.  2. 

The  maxi- 

Kg.  1.. 

mora  weight 

thos  thrown 

on  the  girder,. 

J      -^^     .■- 

■ccording  to^ 

k  olctilatioit 

tnide  at  the 

*! 

time,    would 

Kmotmt  to  2i 

\\     r 

tons  at  each 

of  the  points 
where       the 

.         J^                 1 

prindpalboM 

nponit;  giv- 

\\ u 

were  placed  at  a  short  distance 

ing    a    total 

presatire  of  5 

were  then  laid  acroM  from  one  to 

tons:  this  was 

the  other,  at  the  two  points  a  and 

on   the   snp. 

*;  and  upon  these,  planks  were  laid. 

position  that 

which  cKiried  pigs  of  iron.    They 

the  weight  of 

Ti 

did  not  show  much  symptom  of 

the   roof  it- 

weakness until  4  tons  were  placed 

self,  and  the 

i'i 

on  the  platform ;  but  with  this  load, 

aciiou  of  the 

which  was  Ifissthanone-hslf  of  what 

wind  upon  it. 

the  two  should  have  carried.tbe  two 

wonld   prove 

1 

vertical  braces,  cand  d,  were  broken 

equivalent  to 

by  a  tendency  of  the  under  flange  of 

a   weight   of 

the  girder  to  rise  at  those  points  in  a 

40  rbs.  on  the 

direction  peTpendicularto  the  curve, 

foot   superfi- 

and the  whole  very  soon  gave  way, 

cial. 

The    roof 

this  case,  not  only  was  [he  metal  too 

WM    erected 

thin,  but  the  conneMing  pieces  be- 

by the   eon- 

tween  the  upper  and  lower  flanges 

tractor    who 

^ 

were  too  alight,  and  too  far  apart ; 
the  top  flange  walfcade  wider  than 

'  rF 

pUD,andhad 

the  bottom,  in  order  to  give  a  bed 

undertaken 

for  the  shoe  of  the  principal ,  had 

the  work   at 

1 

the  openuigs  been  filled  in,  the 

hit  own  risk. 

girder  might  have  stood  the  test. 

When  it  ar- 

though  even  then  it  would  have 

tlved  on  the 

been  but  slight. 

gronnd,    the 

fig.  3  shows  two  links  of  a  chain 

sUghtness  of 

(fuy  for  supporting  a  pair  of  shears, 

the     girders 

erected  for  lifting  heavy  weiglit!, 

■w»3  such  as 

such  as  boilers,  &c.:  these  links 

to  render  it 

,//          P 

were  about  6  feet  6  inches  long, 

advisable    to 

and  were  made   of  2-incIi  round 

■nlqect  then 
proof  before 

-'-'  n  -f  '?':, 

iron :  they  were  subjected  to  the 
foUowing  proof  by  means  of  an 
hydraulic  press. 

' 

pUce  them  in  the 

With35  tons,  these!   ,^„    .    , 
two  links  stretched  ;  Tl  ™  ">  ">="■ 

work.     Accordingly,  two   girders 

1,  thew-L  , 
«l  ■    \ 
will  hid  tlien  a  pemunent  ict. 

With  60^  torn  the;  itrelched 
3^  inchn  uid  broke,  the  toetal 
being  clean  and  aound.  In 
tbil  cue  the  breaking  weight  ^8-  3- 
wai  about  double  that  which  .,  ;=,~-. 
mightbaTebeeufurlj'placed  j'v  'J 
opon  the  chain,  tIz.  about 
31  Ions,  vhich  would  ha<e 
been  at  the  rate  of  10  torn 
opon  the  iquare  inch;  for 
although  35  torn  did  not  ap- 
parently cause  any  set  during 
the  time  the  eipcriment 
lasted,  yet  it  ii  impotsible  to 
say  that  that  weight  might 
not  haie  caused  such  an  ef- 
fect, if  left  for  a  aufficieiit 
length  of  time. 

The  foIloHii^  formnla  ii 
deduced  from  Mr.  Hodgkin- 
son's  experiments.  "  As  the 
distance  between  the  aup- 
poris  in  feet  ii  to  the  depth 
in  feet  of  the  beam  in  the 
middle  of  ila  length,  so  i> 
the  area  in  inchea  of  the 
bottom  flange  to  a  fourth 
quantity,  which,  when  mul- 
tipUed  by  a  conitant  number 
to  be  determined  by  eiperi- 
nent,  will  give  the  breaking 
weight  in  tons." 

Thia  giien  number  may  be 
taken  at  27-3«for  common 
beams ;  then  half  of  this  quantity 
will  be  the  weight  which  the  girder 
will  hear,  if  digtributed  equally 
over  its  length.  The  ratio  of  the 
area  of  the  nuddle  section  of  the 
top  flange  to  that  of  the  bottom 
should  'be  about  1  to  4,  or  4-S. 

The  diagram  (fig.  4)  repteseati 
a  girder  of  IS-feet  bearing:  the 
maiimum  weight  which  would  ever 
be  thrown  upon  it,  including  Che 
weight  of  a  fire-proof  floor,  was 


200  fbs.  on  the   foot,    or  U   tons 
spread  over  its  length:  two  of  these 

S'rders  were  placed  at  but  a  short 
stance  apart  from  each  other,  and 


RS.  GIB 

loaded  oniformly  over  tbeir  whole 
surface  with  iron  ballast ;  a  hori- 
lODtal  line  was  struck  upon  oi 
the  girders,  and  the  deflection 
measured  when  each  weight  wsi 
applied. 

Twenty  tons  of  ballast  gave  a 
deflection  of  ^  inch. 


da 


32; 


I 


April  23.— Deflection   still  (he 

same,  the  weight  bating  remained 
undisturbed. 

April  29. — No  alteration  had 
taken  place  in  the  deflection,. and 
the  weights  being  removed,  the 
girder  resumed  its  original  form, 
showing  no  trace  of  a  set  or 
manent  alteration. 

The  section  annexed  shows  the 
relative  proportions  of  the  npper 
and  under  flanges  of  the  girder: 
the  top  and  bottom  of  the  girder 
were  parallel,  but  the  lower  flange, 
being  8  inches  broad  at  the  ml'"" 
diminished  to  i  inches  at  the 
of  support. 


The  computed  breaking  wwgbt, 
according  to  Mr.  Uoi^kiason't  rule, 
would  be 


half  of  this,  viz.  14  tons,  distributed 


GLA 


GLUE. 


GOL 


over  the  whole  length,  should  he 
its  maximum  load;  whereas  it  car- 
ried 18  tons,  or  36  tons  placed  on 
two  girders,  without  showing  any 
symptoms  of  giving. 

The  average  weight  of  a  large 
number  of  these  girders  amounted 
to  about  16f  cwt. 

Gland,  the  pressing  piece  of  a  stuffing, 
box  of  a  steam-engine 

GUus:  this  artificial  transparent  sub- 
stance was  introduced  very  early. 
HoUinshed  says,  an  Englishman 
named  Benedict  Biscop,  who  had 
taken  upon  him  the  habit  of  a 
monk  in  Italy,  came  here  with  the 
Archbishop  of  Rome,  in  the  year 
670,  and  brought  painters,  gla- 
ziers, and  other  such  curious  crafts- 
men into  England  for  the  first  time. 

Glattes  superseded  small  drinking- 
bowls ;  they  were  of  Venetian 
manufacture,  and  probably  first 
brought  here  in  the  16th  century. 
Earlier  they  do  not  appear  to  have 
been  used  in  England ;  nor  to  have 
come  into  much  fashion  till  the 
time  of  Elizabeth. 

Glan  water-gauge.    See  Gauge-gUus. 

Glazing,  the  art  of  affixing  glass  to  the 
sashes  of  windows,  casements,  &c., 
for  the  purpose  of  admitting  the 
Hght  of  day;  anciently  applied 
to  the  affixing  to  windows  deco- 
rative, stained,  and  painted  glass. 
A  great  many  beautiful  examples 
exist  in  this  and  other  countries, 
of  early  designs,  and  of  examples 
in  the  cinque-cento  style :  for  the 
latter,  see  '  Divers  Works  of  Early 
Masters,'  2  vols,  folio,  1846. 

Glazing  is  also  a  term  applied  to 
the  finishing  of  a  drawing  with 
some  thin,  transparent,  and  glossy 
tint,  through  which  the  first  co- 
lours appear,  and  are  heightened 
in  their  effect 

Glebe,  turf,  soil;  land  possessed  as 
part  of  the  revenue  of  an  ecclesias- 
tical benefice 

GUst,  a  shining  black  or  brown  mine- 
ral, of  an  iron  cast 

Ghte,  a  tenacious  viscid  matter,  which 
is  used  as  a  cement  by  carpenters, 

207 


joiners,  &c.     Glues  are  found  to 
differ  very  much  from  each  other 
in  their  consistence,  colour,  taste, 
smell,  and  solubility.    Some  will 
dissolve  in  cold  water,  by  agitation ; 
while  others  are  soluble  only  at  the 
point  of  ebullition.    The  best  glue 
is  generally  admitted  to  be  trans- 
parent, and  of  a  brown  yellow  co- 
lour, without  either  taste  or  smell. 
It  is  perfectly  soluble  in  water, 
forming  a  viscous  fluid,  which  when 
dry  preserves  both  its  tenacity  and 
transparency  in  every  part,    and 
has  soUdity,  colour,  and  viscidity, 
in  proportion  to  the  age  and  the 
strength  of  the  animal  from  which 
it  is  produced.      To    distinguish 
good  glue  from  bad,  it  is  necessary 
to  hold  it  between  the  eye  and  the 
light ;  and  if  it  appears  of  a  strong 
dark  brown  colour,  and  free  from 
cloudy  or  black  spots,  it  may  be 
pronounced  to  be  good.    The  best 
glue  may  Ukewise  be  known  by 
immersing  it   in    cold  water  for 
three  or  four  days,  and  if  it  swells 
powerfully  without  melting,  and 
afterwards  regains  its  former  di- 
mensions and  properties  by  being 
dried,  the  article  is  of  the  best 
quality. 

A  small  portion  of  finely  levi- 
gated chalk  is  sometimes  added  to 
the  common  solution  of  glue  in 
water,  to  strengthen  it  and  fit  it  for 
standing  the  weather. 

A  glue  that  wiU  resist  both  fire 
and  water  may  be  prepared  by 
mixing  a  handful  of  quicklime  with 
four  ounces  of  linseed  oil,  thorough- 
ly levigated,  and  then  boiled  to  a 
good  thickness,  and  kept  in  the 
shade,  on  tin  plates,  to  dry.  It 
may  be  rendered  fit  for  use  by 
boiling  it  over  a  fire  in  the  ordi- 
nary manner. 
Glypha,    perpendicular    flutings    or 

channels  used  in  the  Doric  frieze 
Gobbets,  stones ;  a  measure  or  quan- 
tity, so  called  in  the  time  of  Ed- 
ward III. 
Gola,  the  Italian  term  for  cyrna 
Gold,  a  well-known  valuable  metal 


GOL 


GOVERNOR. 


GOV 


/ 


found  in  many  parts  of  the  world, 
but  the  grreatest  quantity  of  which 
is  obtained  from  the  coast  of 
Guinea.  The  produce  of  California 
remains  to  be  determined.  Gold 
seems  to  be  the  most  simple  of  all 
substances.  It  is  spoken  of  in  Scrip- 
ture, and  the  use  of  it  among  the 
ancient  Hebrews,  in  its  native  and 
mixed  state,  and  for  the  same  pur- 
poses as  at  present,  was  very  com- 
mon. The  ark  of  the  covenant 
was  overlaid  with  pure  gold;  the 
mercy  seat,  the  vessels  and  utensils 
belonging  to  the  tabernacle,  and 
those  also  of  the  House  of  the 
Lord,  as  well  as  the  drinking- 
vessels  of  Solomon,  were  formed 
of  this  metal. 

Gold  occurs,  in  the  metallic  state, 
mixed  with  several  metals,  but 
more  commonly  with  silver  and 
copper,  and  sometimes  pure. 

Golden  sulphur  of  antimony ^  golden 
yellow ^i^  the  hydro-sulphuret  of  an- 
timony, of  an  orange  colour,  which 
is  destroyed  by  the  action  of  strong 
light.  It  is  a  bad  dryer  in  oil, 
injurious  to  many  colours,  and  in 
no  respect  an  eligible  pigment 
either  in  oil  or  water. 

Gold  purple  i  or  Ca8siu8*8  purple  preci- 
pitate, the  compound  oxide  which  is 
precipitated  upon  mixing  the  solu- 
tions of  gold  and  tin.  It  is  not  a 
bright,  but  a  rich  and  powerful 
colour,  of  great  durability,  varying 
in  degrees  of  transparency,  and  in 
hue  from  deep  crimson  to  a  mur- 
rey or  dark  purple:  it  is  princi- 
pally used  in  miniature  painting, 
and  may  well  be  employed  in  ena- 
mel painting. 

Gondola,  a  Venetian  barge  much  or- 
namented, used  in  the  canals  of 
Venice  for  the  convenience  of  the 
inhabitants:  the  common  dimen- 
sions are  30  feet  by  4  feet :  each 
end  is  terminated  by  a  very  sharp 
point,  which  is  raised  perpendicu- 
larly to  the  full  height  of  a  man 

GoniometeTf  an  instrument  for  mea- 
suring angles  and  crystals 

Gorged,  in  heraldry,  the  bearing  of  a 

208 


crown,  coronet,  or  the  like,  about 
the  neck  of  a  lion,  swan,  &c. 

Gossan,  an  imperfect  iron  ore,  com- 
monly of  a  tender  rotten  substance, 
and  of  a  red  or  rusty  iron  colour 

Gothic  Architecture,  usually  so  called. 
Both  Mr.  Britton  and  Mr.  Pugin 
have  treated  of  it  by  the  name 
of '  Christian  Architecture.'  It  had 
its  rise  from  the  Romanesque :  this 
took  its  origin  from  Roman  remains 
at  the  declension  of  that  empire. 
It  became  Saxon,  then  Norman, 
and  varied  in  its  character  with  the 
maturity  of  years.  It  was  Early 
English,  Perpendicular,  Decorated, 
Flamboyant,  &c.,  till  it  lost  its  ec- 
clesiastical and  monastic  character 
in  the  Domestic,  which  prevailed 
in  the  Tudor  style  (Renaissance), 
followed  by  the  EUzabethan,  &c. 

Gouge,  in  carpentry,  an  instrument 
like  a  round  hollow  chisel 

Governor,  the  apparatus  for  regulating 
the  supply  of  steam  to  the  cylinder 
so  as  to  give  a  constant  velocity  to 
the  engine.  It  consists  of  two  balls 
suspended  from  a  vertical  spindle, 
and  revolving  with  it :  the  suspend- 
ing rods  are  connected  by  arms  to 
a  sliding-piecewhich  fits  the  spindle 
and  acts  upon  a  lever  attached  to  a 
throttle- valve  in  the  steam-pipe: 
the  balls  rise  by  the  centrifugal 
force  as  the  velocity  increases,  and 
close  the  valve :  when  the  velocity 
diminishes,  the  balls  fall,  and  open 
the  valve. 

Governor,  a  contrivance  for  equalizing 
the  motion  of  mills  and  machinery, 
as  well  as  being  used  as  above  de- 
scribed 

Governor  balls,  the  solid  metal  balls 
fixed  on  the  ends  of  the  suspending 
rods  of  the  governor 

Governor  {gas).  The  governor  is  a 
machine  for  regulating  and  equal- 
izing the  flow  of  gas  from  the  gaso- 
meters to  the  street-mains,  and  is 
much  more  perfect  in  its  action 
than  any  slide-valve  applied  for 
that  purpose  requiring  attendance. 
Its  use  is  no  where  sufficiently  ap- 
preciated.    Had  it  been  a  conipli- 


GOW 


GRANITE. 


GRA 


cated  piece  of  machinery,  or  ex- 
pensive in  its  first  cost  and  after- 
application,  objections  to  its  adop- 
tion would  not  have  been  surprising, 
— ^bat  it  is  perfectly  simple,  its  ac- 
tion is  certain  and  unvarying,  and 
its  first  cost  inconsiderable. 

The  velocity  of  gas  in  the  mains 
and  pipes  of  supply  is,  in  the  first 
instance,  as  various  as  there  are 
differences  in  their  altitudes  and 
extent.  A  main  at  one  place  will 
fumbh,  with  a  certain  pressure  of 
gas,  a  flame  one  inch  high ;  while 
at  a  dififerent  altitude  it  will  furnish 
a  flame  double  that  height.  If, 
again,  in  the  direction  of  the  nudn 
there  are  many  bends,  angles,  or 
contractions  in  its  diameter,  the 
velocity  of  the  gas  through  it  will 
vary  considerably  more  than  if  it 
were  direct  and  uniform.  If  the 
pipe  be  of  any  great  length,  and  of 
uniform  bore,  but  unequally  fur- 
nished vnth  branches,  the  burners 
will  be  unequally  supplied  with  gas : 
those  which  are  near  its  head  will 
be  supplied  vnth  a  fuller  stream  of 
gas  than  those  which  are  situated 
towards  its  termination. 

Independently   of  these  differ- 
ences,   arising   from   diversity  of 
local  positions,  there  will  always  be 
one  great  variation  in  the  velocity 
of  the  gas,  occasioned  by  the  va- 
riety of  periods  during  which  lights 
are  required  by  different  consumers 
supplied  from  the  same  main  or 
system  of  pipes :  for  example,  when 
a  certain  number  of  burners  is  to 
be  supplied,  and  it  happens  that 
one-half  are  shut  off  sooner  than 
the  rest,  the  velocity  of  the  gas  in 
the  mains  vdll  be  materially  in- 
creased, and  the  remaining  lamps 
should  be  turned  down ;  but  many 
would  not  be  reduced,  and  much 
gas  would  be  lost. 
Gowarif  decomposed  granite ;  but  the 
term  is  sometimes  applied  to  the 
solid  rock 
GozzaUf  oxide  of  iron  and  quartz 
Grace  is  taken  for  beauty,  graceful 
form  or  agreeableness  of  person; 


for  form,  friendship,  and  kindness; 
for  certain  gilts  of  God,  which  He 
bestows  freely,  when,  where,  and 
on  whom  He  pleases :  such  are  the 
gifts  of  miracles,  prophecy,  lan- 
guage, &c. 

Grace  principally  consists  in  the  turn 
that  a  painter  gives  to  his  objects, 
to  render  them  agreeable, — even 
those  that  are  inanimate.  It  is 
more  seldom  found  in  the  face  than 
in  the  manner ;  for  our  manner  is 
produced  every  moment,  and  can 
create  surprise.  A  woman  can  be 
beautiful  but  one  way,  yet  she  can 
be  graceful  a  thousand.  Grace  is 
neither  found  in  constrained  nor  in 
affected  manners,  but  in  a  certain 
freedom  and  ease  between  two  ex- 
tremes. 

Gradation^  in  painting  and  drawing, 
implies  the  gradual  receding  of 
objects  into  the  remote  distance, 
by  a  proper  strength  or  due  dimi- 
nution of  light,  shade,  and  colour, 
according  to  their  different  dis- 
tances, the  quantity  of  light  which 
shines  upon  them,  and  the  medium 
of  air  through  which  they  are  seen 

Gradientf  a  deviation  from  a  level 
surface  to  an  inclined  plane 

Graduation^  the  division  of  philo- 
sophical instruments  into  degrees 
and  other  minute  parts 

Gram  tin,  the  finest  tin,  smelted  with 
charcoal ;  also  the  ore  of  very  rich 
tin  sometimes  found  in  the  form  of 
grains  or  pebbles 

Grange,  a  monastic  farming  establish- 
ment :  in  ancient  times  it  was  com- 
mon to  attach  farm-houses  and 
granaries  to  the  estates  of  religious 
institutions 

Granite,  a  natural  stone  of  great 
strength,  hardness,  and  durability ; 
much  used  in  building:  it  is  a 
primary  and  unstratified  rock,  con- 
sisting of  quartz,  mica,  and  felspar, 
each  crystallized  and  cohering,  but 
without  any  base  or  cement 

Greqmel,  in  navigation,  a  sort  of  small 
anchor  with  fbur  or  five  flukes  or 
claws,  commonly  used  for  boats 
and  small  vessels 


209 


GRA 


GREGORIAN  CHANT. 


GRE 


Gravel,  a  geological  term  applied  to 
those  sabulous  soils,  or  assemblages 
of  worn  and  rounded  stones,  which 
are  found  scattered  on  the  surface 
of  the  earth 

Graver,  the  burin  of  an  engraver ;  a 
square  piece  of  steel  fixed  In  a 
handle,  and  bevelled  diagonally  at 
the  end:  an  instrument  used  for 
turning  iron,  after  it  has  been 
rough^  out  by  the  'heel  tool,'  is 
so  called 

Gravity  is  that  power  or  force  which 
causes  bodies  to  approach  each 
other.  This  universal  principle, 
which  pervades  the  whole  system 
of  nature,  may  be  enunciated  as 
follows  :  the  mutual  tendency  of 
two  bodies  towards  each  other  in- 
creases in  the  same  proportion  as 
their  masses  are  increased,  and  the 
square  of  their  distance  is  decreased; 
and  it  decreases  in  proportion  as 
their  masses  are  decreased,  and  as 
the  square  of  their  distance  is  in- 
creased. 

Gravity  is  also  the  force  wherewith  a 
body  endeavours  to  descend  to- 
wards the  centre  of  the  earth :  this 
is  called  absolute  gravity  when  the 
body  tends  downwards  in  free  space, 
and  relative  gravity  is  the  force  it 
endeavours  to  descend  with  in  a 
fluid.  Terrestrial  gravity  is  that 
force  by  which  bodies  are  urged 
towards  the  centre  of  the  earth, 
and  it  is  measured  by  the  velocity 
generated  in  a  second  of  time.  Ex- 
periments show  that  a  falling  body 
describes  16i^  feet  in  one  second, 
and  it  has  then  acquired  a  velocity 
of  32^  feet,  which  is  therefore  the 
true  measure  of  the  force  of  gravity. 

Gray  colour  is  the  third  and  last, 
being  the  nearest  in  relation  of  co- 
lour to  black.  In  its  common  ac- 
ceptation, gray  denotes  a  class  of 
cool  cinerous  colours,  faint  in  hue ; 
whence  we  have  blue-grays,  olive- 
grays,  green-grays,  purple-grays, 
and  grays  of  all  hues,  in  which 
blue  predominates ;  but  no  yellow 
or  red  grays,  the  predominance  of 
such  hues  carrying  the  compounds 

210 


into  the  classes  of  brown  and  mar- 
rone,  of  which  gray  is  the  natural 
opposite. 

Graywacke,  a  coarse  slate;  in  geo- 
logy, a  secondary  rock 

Grease-cockf  a  short  pipe  fixed  in  the 
cylinder  cover  of  a  steam  engine, 
with  two  stop-cocks  inserted  at  a 
short  distance  apart,  and  a  funnel  at 
the  top  for  holding  tallow.  When 
the  upper  cock  is  opened,  the  taUow 
falls  into  the  intermediate  space; 
the  cock  is  then  closed,  and  the 
lower  one  opened  for  the  melted 
grease  to  enter  the  cylinder,  and 
lubricate  the  piston  without  allow- 
ing the  steam  to  escape. 

Green  verditer  is  the  same  in  substance 
as  blue  verditer,  which  is  converted 
into  green  by  boiling  it 

Green  ebony  wood,  imported  from  the 
West  Indies,  is  used  for  round 
rulers,  turnery,  marquetry -work, 
&c. ;  it  is  also  much  used  for  dyeing, 
and  contains  resinous  matter 

Greenheart  wood,  from  the  West  In- 
dies, resembles  cocoa  wood  in  size 
and  bark,  and  is  used  for  turnery 
and  other  works 

Grees,  steps ;  also  a  staircase 

Gregorian  Chant:  Cantus  Gr^;oria- 
nus,  Cantus  Firmus,  Cantus  Planus 
or  Planus,  in  Latin ;  Canto  Firmo, 
in  Italian;  Plein  Chant,  in  French; 
Plain  Chant,inEnglish;  and  Choral, 
in  German.  This  species  of  music 
is  the  most  ancient  of  all,  and  is 
still  the  only  one  properly  adapted 
to  the  ritual  services  of  the  Chris- 
tian churches. 

The  Gregorian  chant  consists  of 
a  few  notes,  on  which  the  words 
of  the  Liturgies  are  recited.  The 
earliest  specimens  in  existence  con- 
sist of  only  one  or  two  notes,  and 
were  used  by  St.  Ambrose,  at  Milan, 
in  the  fourth  century.  The  origin 
of  this  chant  is  traced  to  the  earUer 
churches  of  Egypt,  Thebes,  Pales- 
tine, Arabia,  Phoenicia,  Syria,  &c., 
from  whence  it  was  introduced  into 
the  church  of  Constantinople  by 
St.  John  Chrysostom.  St.  Ambrose 
is  said  to  have  brought  it  into  use 


GRE 


GREGORIAN  CHANT. 


GRI 


in  Milan,  **  after  the  custom  of  the 
inhabitants  of  the  East/'  and  from 
Milan  it  came  to  Rome  "  long  be- 
fore the  time  of  St.  Gregory."  But 
88,  in  the  course  of  time,  various 
mutations  had  taken  place,  St.  Gre- 
gory, in  order  to  reform  and  settle 
the  music  for  the  church,  made  a 
compilation  of  such  as  was  fit  for 
its  use,  and  formed  the  first  ritual 
book  of  music,  or  Roman  Anti- 
phonarium.  From  the  order  which 
he  gave  it,  and  in  consequence  of 
this  work  of  Gregory  being  after- 
wards established  in  the  other  (the 
Western)  churches,  it  received  the 
name  Gregorian.  We  have  very 
little  of  the  music  ascribed  to  Gre- 
gory himself,  a  specimen  of  which 
is  given  by  Mr.  Spencer  in  his  work 
on  the  church  modes,  and  is  very 
grand.  A  portion  of  the  old  Gre- 
gorian chant  is  still  used  in  our 
cathedrals  in  the  so-called  intoning 
the  service'  by  the  minor  canons, 
and  also  in  the  responses  by  the 
choir,  but  in  a  very  mutilated  form. 
But  in  the  chanting  of  the  prose 
Psalms,  it  is  almost  entirely  aban- 
doned; the  only  specimen  (and 
that  somewhat  mutilated)  being 
the  grand  and  well-known  'Tallis's 
chant.'  There  is  a  remarkable 
difference  between  the  Gregorian 
melodies  for  the  Psalter  and  Can- 
tides  (and  which  are  called  the 
eight  tones)  and  those  of  a  more 
modem  date.  No  such  thing  as  a 
double  chant  exists  in  Gregorian 
music,  and  the  *  tones '  are  formed 
on  one  general  law ;  i,e,  a  *  tone ' 
consists  of  one  principal  note,  called 
the  Dominant,  t.  e.  the  predominant 
or  reciting  note,  upon  which  the 
principal  part  of  each  half-verse  is 
chanted,  the  remainder  being  in- 
flected in  cadences  of  one  or  several 
notes  revolving  (as  it  were)  above 
and  below  the  dominant,  or  ter- 
minating on  the  final  of  the  mode ; 
and  it  is  a  law  that  the  reciting 
parts  are  always  (when  the  tone  is 
regular)  on  the  same  note,  viz.  the 
dominant.     There   are   very  few 

211 


instances  of  any  deviation  from 
this  rule.  In  the  modem  system 
there  seems  to  be  a  total  absence 
of  any  rule  of  this  sort,  and  the 
cadences,  both  in  the  middle  of  the 
verse  and  at  the  end,  consist  of  a 
greater  number  of  notes,  and  these 
of  unequal  value.  Moreover,  in  the 
Gregorian  chant  no  attention  is 
paid  to  time ;  it  is  regulated  entirely 
by  emphasis  and  syllabic  quantity, 
not  by  time  and  accent,  as  in  mo- 
dem chanting.  On  Sundays  and 
the  greater  festivals  it  is  a  rule  to 
commence  the  *  tone '  with  a  few 
preliminary  notes,  called  the  into- 
nation, which  serve  as  an  inchoa- 
tion,  or  induction  to  the  dominant, 
or  reciting  note :  on  other  occa- 
sions, these  initial  notes  are  not 
useA.  For  specimens  of  the  adap- 
tation of  these  Gregorian  tones  or 
chants  to  the  Canticles,  &c.  of  the 
Enghsh  church,  see  the  *  Hymnal,' 
by  Mr.  Spencer. 

Gregorian  music  requires  a  nobler 
and  more  rigid  harmony  than  can 
be  given  in  the  modern  system; 
and  its  effects  in  the  divine  ofiices, 
when  properly  harmonized  and 
performed,  are  far  superior  to  any 
other  kind  of  church  music. 

Greutf  or  Grit,  a  kind  of  fossil  body, 
consisting  of  sandy,  rough,  hard, 
earthy  particles 

Grey.    See  Gray, 

Griddle,  a  large  wire  sieve,  used  in- 
stead of  a  hurdle,  for  sifting  and 
sorting  copper  ore  as  it  rises  from 
the  mine 

Griffin,  in  heraldry,  a  fabulous  animal, 
feigned  to  be  between  the  lion  and 
eagle,  and  to  have  the  paws  and 
head  of  the  first,  with  the  beak  and 
wings  of  the  last 

Grindstone,  a  cylindrical  stone,  on 
which,  being  turned  round  its  axis, 
edge-tools  are  sharpened  by  apply- 
ing their  edges  to  the  convex  surface 

Gripe,  the  lower  part  of  the  knee  of 
the  head  that  connects  with  the 
foremost  end  of  the  keel  of  a  vessel 

Grit,  coarse  sand;  rough  hard  par- 
ticles of  sandstone 


GRO 


GROINS. 


GRO 


(rroirif  the  angle  formed  by  an  inter- 
section of  vaults:  most  of  the 
vaulted  ceilings  of  the  buildings  of 
the  middle  ages  were  groined,  and 
therefore  called  groined  ceilings. 
During  the  early  part  of  the  Nor- 
man style  the  groins  were  left  pur- 
posely plain,  but  afterwards  they 
were  invariably  covered  with  ribs. 
GroinSy  in  coast  engineering.  A  groin 
is  a  frame  of  wood-work,  con- 
structed across  a  beach,  between 
high  and  low  water,  perpendicular 
to  the  general  line  of  it,  either  to 
retain  the  shingle  already  accumu- 
lated, to  recover  it  when  lost,  or  to 
accumulate  more  at  any  particular 
point ;  also  to  break  and  check  the 
action  of  the  waves. 

The  component  parts  of  a  groin 
are  piles,  planking,  land-ties,  land 
tie-bars,  blocks,  tail-piles,  and  keys 
and  screw-bolts. 

The  length  of  a  groin  depends 
on  the  extent,  and  the  requisite 
strength  of  its  component  parts  on 
the  nature  of  the  beach  on  which 
it  is  to  be  constructed. 

Those  at  Eastbourne,  on  the  coast 
of  Sussex,  of  which  the  following 
is  more  particularly  a  description, 
are  from  150  to  250  feet  in  length, 
and  the  beach  at  that  place  being 
very  rough,  consisting  of  coarse 
heavy  shingle  and  large  boulders, 
they  require  to  be  composed  of 
proportion  ably  strong  materials  to 
resist  its  force. 

The  piles  are  from  1 2  to  25  feet 
long,  and  8  by  6^  inches  scantling, 
shod  with  iron. 

The  planking  is  in  lengths  of  8, 
12,  and  16  feet,  2^  inches  thick, 
and  with  parallel  edges. 

The  land- ties  are  of  rough  timber 
from  20  to  25  feet  long,  and  large 
enough  at  the  but-end  to  receive 
the  bars. 

The  land  tie-bars  are  13  ft.  6  in. 
long,  and  12  by  5  in.  scantling. 

The  land  tie-bar  blocks  are  about 
2  feet  long,  and  of  the  same'  scant- 
ling as  the  piles. 

The  land-tie  tail-keys  are  about 


2  feet  6  inches  long,  and  6  by  2^ 
inches  scantling. 

The  above  materials  are  of  oak 
or  beech. 

The  screw-bolts  are  of  inch  round 
iron,  2  feet  9^  inches  and  2  feet 
1^  inch  long,  in  equal  proportions. 

The  relative  proportions  of  the 
component  parts  are,  four  piles,  one 
land-tie  with  tail-piles  and  keys, 
one  land  tie-bar  with  two  blocks, 
two  long  and  two  short  bolts,  about 
180  square  feet  of  planking,  and 
about  140  six-inch  spikes  for  every 
16  feet  in  length ;  and  the  expense 
of  a  groin,  constructed  with  mate- 
rials of  the  above  dimensions,  may 
be  calculated  at  about  £  30  for  the 
same  length. 

GENERAL  ROLES  OBSERVED  IN 
THE  CONSTRUCTION. 

When  the  object,  in  constructing 
a  groin,  is  to  recover  shingle,  or 
accumulate  more,  the  first  pile  is 
driven  at  the  high-water  mark  of 
neap-tides,  leaving  its  top  level  with 
that  of  spring-tides.  The  next  is 
driven  at  the  point  on  the  sands, 
beyond  the  bottom  of  the  shingle,  to 
which  the  groin  is  to  extend,  leaving 
about  4  feet  of  it  out  of  the  beach. 

The  tops  of  these  two  piles  may 
be  taken  for  the  general  slope  of 
the  groin,  unless  the  beach  should 
be  very  steep,  and  much  curved, 
in  which  case  it  becomes  necessary 
to  follow  its  curvature  in  some 
degree. 

From  the  high-water  mark  of 
neap-tides,  the  piles  are  carried 
back  nearly  level  to  that  of  spring- 
tides, and  as  much  further  as  may 
be  considered  necessary. 

Thepiles  are  driven  4  feet  asunder 
from  centre  to  centre,  and  so  as  to 
admit  the  planking  between  them 
alternately,  and  they  should  be  sunk 
about  two-thirds  of  their  length. 

The  longest  piles  are  placed  be- 
tween the  high-water  mark  of  neap- 
tides  and  the  bottom  of  the  shingle, 
particularly  from  20  to  40  feet 
below  the  former  point. 

The  planking  is,  if  possible,  car- 


212 


GRO 


GUSSETS. 


GUS 


ried  down  to  about  two.thirds  from 
the  tops  of  the  piles,  and  kept 
parallel  with  them. 

The  land-ties  are  placed  about 
one-third  from  the  top  of  the  plank- 
ing (supposing  the  latter  to  com- 
mence from  the  tops  of  the  piles), 
and  their  tails  are  sunk  to  the  level 
of  the  bottom  of  the  planking,  or 
as  nearly  so  as  possible. 

Grotesque.  This  term,  which  is  now 
familiar  among  all  the  lovers  of  the 
art  of  painting,  was  by  the  Italians 
appropriated  to  that  peculiar  man- 
ner of  composition  and  invention 
observed  among  the  antique  mo- 
numental paintings  which  were 
discovered  in  the  subterraneous 
chambers  that  had  been  decorated 
in  the  times  of  the  ancient  Romans ; 
and  as  the  Italians  apply  the  word 
Grotto  to  express  every  kind  of 
cave  or  grot,  all  paintings  which 
were  in  imitation  of  the  antique 
designs  discovered  in  those  cham- 
bers, which  for  ages  had  been 
covered  with  ruins,  are  grotesqued 
or  grotesque,  which  is  now  applied 
to  English  subjects  of  a  quaint  and 
anomalous  character. 

Grotesguet  a  name  given  to  the  light 
and  fanciful  ornaments  used  former- 
ly to  characterize  persons  and  things 

Grotto,  a  natural  or  artificial  cavern 
or  cave 

Grouan  lode,  any  tin  lode  which 
abounds  vidth  rough  gravel  or  sand 

Ground-plate  or ffroundsillf  the  lowest 
plate  of  a  wooden  building  for  sup- 
portingthe  principal  and  other  posts 

Grounds f  pieces  of  wood  fixed  to  walls 
and  partitions,  with  their  surfaces 
flush  virith  the  plaster,  to  which  the 
facings  or  finishings  are  attached 

Ground  table  stones,  the  projecting 
course  of  stones  in  a  wall  above  the 
plinth 

Ground-ways,  large  pieces  of  timber 
laid  across  a  ship  or  dock,  and 
upon  which  the  blocks  are  placed 

Grouping  is  the  combining  or  joining 
objects  in  a  picture  for  the  satis- 
faction of  the  eye,  and  also  for  its 
repose;  and  although  a  picture  may 

213 


consist  of  diflferent  groups,  yet  those 
groups  of  objects,  managed  by  the 
chiaro-oscuro,  should  all  tend  to 
unity,  and  one  only  should  predo- 
minate 

Guag,  Cornish.  Tinners,  holeing  into 
a  place  which  has  been  wrought 
before,  call  it  holeing  in  guag 

Gudgeon,  the  iron  piers  fixed  in  a 
beam  or  wooden  shaft  for  bearings 

Gudgeons,  in  ship-building,  are  eyes 
driven  into  the  stem-post,  to  hang 
the  rudder  on 

Guide-blocks,  pieces  of  metal  with 
parallel  sides,  fitted  on  the  ends  of 
a  cross-head  of  a  steam  engine,  to 
slide  in  grooves  in  the  side  frames, 
and  keep  the  motion  of  the  piston- 
rod  in  a  direct  line 

GuiUoche,  an  ornament  used  in  classi- 
cal architecture,  formed  by  two  or 
more  intertwining  bands 

Gules,  in  heraldry,  a  red  colour 

Gulph  of  ore :  a  lode  which  throws 
up  very  g^eat  quantities  of  ore,  and 
proves  lasting  and  good  in  depth,  is 
so  called 

Gum  wood,  or  blue  gum  wood,  is  the 
produce  of  New  South  Wales,  sent 
over  in  large  logs  and  planks  simi- 
lar to  dark  Spanish  mahogany :  it 
is  used  in  ship-building,  &c. 

Gun-metal,  a  mixed  metal,  an  alloy 
of  copper  and  tin 

Gunnies,  in  Cornish,  a  term  applied 
to  breadth  or  width :  single  gunnies 
are  3  feet  wide 

Gunter*s  chain,  the  chain  in  common 
use  for  measuring  land:  the  length 
of  the  chain  is  66  feet,  or  22  yards, 
or  4  poles  of  5^  yards  each;  it 
is  divided  into«100  Hnks  of  7'92 
inches  each.    See  Acre. 

Gunwale,  or  gunnel,  in  ship>building, 
the  piece  of  timber  which  reaches 
on  either  side  of  the  ship  from  the 
half-deck  to  the  forecastle 

Gunwale,  the  plank  that  covers  the 
heads  of  the  timbers  between  the 
fore  and  main  drifts 

Gussets,  as  understood  in  mechanical 
construction,are  brackets  orangular 
pieces  of  iron,  to  strengthen,  to  keep 
steady,  and  support  a  structure. — 


GUS 


HALF-TIMBERED  HOUSES. 


GYP 


In  the  construction  of  the  rect- 
angular coyered  openings  of  the 
Britannia  and  Conway  iron  bridges, 
gussets  are  used  extensively  in  the 
interior,  consisting  of  double  tri- 
angular plates  riveted  to  the  bot- 
tom and  sides  of  the  plates  of  the 
bridge,  as  a  series  of  brackets  (and 
at  the  top  and  either  sides  also),  to 
add  to  the  strength  and  durability 
of  these  extraordinary  works,  and 
as  a  counter-effort  to  the  tendency 
of  strain  on  the  lower  sides  to  se- 
parate or  open  the  joints,  and  on 
the  upper  side  to  force  them  closer 
together. 

Cftuto,  a  term  used  by  the  Italians, 
signifying  taste  in -the  design  of  the 
attitudes,  good  arrangement,  and 
composition  of  a  picture 

Guttttt  ornaments  resembling  drops, 
placed  in  the  epistylium  of  the 
Doric  order  below  the  triglyphs. 
They  occur  likewise  in  the  under 


HAD 

Hads,  in  mining,  the  underlay  or 
inclination  of  the  vein 

Half-pace^  or  Hauie-paee,  a  raised 
floor  in  a  bay  window. 

Half-timbered  homes:  this  mode  of 
constructing  domestic  buildings  was 
practised  in  England  and  on  the 
Continent  during  the  reigns  of 
Henry  VIII.  and  Elizabeth.  It  was 
peculiarly  of  a  picturesque  charac- 
ter ;  the  foundations  and  principal 
supports  were  of  stout  timber,  and 
the  interstices  of  the  fronts  were 
filled  with  plaster.  In  many  cases 
the  ornamental  timber  framing  was 
of  a  dark  colour,  which,  with  the 
barge-board  gable,  gave  the  whole 
an  exceedingly  interesting  appear- 
ranee.  There  are  yet  remaining 
some  very  fine  examples  in  England, 
particularly  in  the  western  and 
north-western  counties. 

Haif'HmberSf  in  ship-building,  those 
timbers  in  the  cant  bodies  which 
are  answerable  to  the  lower  fut- 
tocks  in  the  square  body 


face  of  the  mutules  in  the  Doric 
corona.  ^They  are  supposed  to  have 
originated  from  the  intention  to 
represent  drops  of  water  running 
off  the  roof,  adhered  to  the  under 
surface  of  the  canterii  or  rafters  of 
early  buildings. 

Gybing^  in  navigation,  the  shifting  of 
any  boom-sail  from  one  side  of  the 
mast  to  the  other 

Gymnasium^  a  public  building  used 
by  the  Greeks  for  the  practice  and 
exercise  of  gymnastics,  or  mus- 
cular development;  also  a  place, 
according  to  Yitruvius,  for  amuse- 
ments and  scientific  recreation 

Gynaceumf  in  Greek  architecture,  the 
apartment  of  the  females  in  the 
interior  of  the  house ;  the  nursery 

Gypsoplaste,  a  cast  taken  in  plaster  of 
Paris  or  white  lime 

Gypsum^  sulphate  of  lime,  called  also 
pbister  of  Paris,  selenite,  and  ala- 
baster 


HAM 

HcM,  the  principal  apartment  in  the 
domestic  houses  of  the  middle  ages; 
a  place  of  asiicmbly;  a  spacious 
building  attached  to  inns  of  court 

HalHardSi  in  navigation,  the  ropes  or 
tackles  usually  employed  to  hoist  or 
lower  any  sail  on  its  respective  mast 

Halites,  the  hangings  of  a  hall 

Haham,  in  Cornish,  the  refuse  ore 

Hamt  in  Saxon,  a  honse,  farm,  or  vil- 
lage 

Hamburgh  lake  is  a  colour  of  great 
power  and  depth ;  rather  purpleiah, 
or  inclining  to  crimson:  it  dries 
with  extreme  difficulty,  but  diflTers 
in  no  other  essential  quality  from 
other  cochineal  lakes 

HammeT'beamSf  horizontal  pieces  of 
timber,  frequently  used  in  the  roofs 
of  old  English  buildings,  in  pairs 
on  the  opposite  sides  of  the  same 
roof;  often  used  also  in  the  prin- 
cipals of  Gothic  roofs,  to  strengthen 
the  framing  and  to  diminish  the 
lateral  pressure  that  falls  upon  the 
walls 


214 


HAN 


HAND-GEAR. 


HEA 


Nances,  in  architecture,  ends  of  ellip- 
tical arches,  which  are  arcs  of 
smaller  circles  than  the  scheme  or 
middle  part  of  the  arch 
Hand-brace,  a  tool  for  horing,  con- 
sisting of  a  cranked  spindle,  at  one 
end  of  which  a  hroad  head  or 
breast-plate  is  attached  by  a  swiTel, 
so  that  it  may  remain  stationary 
while  the  crank  is  turned ;  at  the 
other  end  is  a  socket,  into  which 
a  drill  can  be  fixed 
Hand^riUing machine jd^  small  drilling 

machine  turned  by  manual  labour 
Hand-gear,   in  a  locomotive  engine, 
the  handles  of  the  working  gear, 
placed   conveniently  to  the  foot- 
plate, so  as  to  be  within  reach  of 
the  engine-man  when  he  requires 
to  use  them  for  regulating  the  dif- 
ferent parts  of  the  engine 
Hand-pump,  in  a  locomotive  engine, 
the  pump  placed  by  the  side  of  the 
fire-box,  to  be  worked  by  a  hand- 
lever  when  the  engine  has  to  stand 
with  steam  up 
Hand-railing,  in  a  locomotive  engine, 
the  railing  along  the  sides  of  the 
engine,  to  protect  persons  passing 
to  the  front  of  the  engine  for  any 
necessary  purpose 
Handsaw,  a  saw  from  12  to  15  inches 
in  length,  fixed  in  an  iron  frame, 
with  a  handle  at  one  end;   used 
for  cutting  wood  or  metal 
Harmony  is  the  general  accordance  of 
the  objects  in  a  painting  with  one 
another,  and  their  subordination  to 
the  principal  object;  so  that  all 
unite  to  constitute  a  pleasing  whole. 
It  is  effected  by  a  due  combination 
of  lights  and  shades,  by  the  union 
and  colour,  or  by  such  constrasts 
as  are  sufficient  to  relieve  the  dis- 
tant groups. 
Harmony    of  colours.      Lessons    in 
colouring  have  ever  been  given, 
notwithstanding  it  is  a  part   so 
principal  in  painting,  that  it  has 
its  rules  founded  on  science  and 
reason.     Without  such  study,  it  is 
impossible  that  youth  can  acquire 
a  good  taste  in  colouring,  or  un- 
derstand harmony. 

215 


Harpinffs,  pieces  of  oak  which  hold 
the  timbers  of  the  fore-and-aft 
cant-bodies  till  a  ship  is  planked 

Hatches,  the  coverings  for  the  hatch- 
ways of  a  ship,  made  vnth  ledges, 
and  laid  with  oak  or  deal,  and 
caulked 

Hatching  is  shadoviring  ¥rith  a  black- 
lead  pencil  or  pen:  it  is  done 
either  in  straight  lines  or  zigzag 
strokes,  such  as  are  seen  in  pencU 
drawings,  or  in  pencilled  back- 
grounds. It  is  used  by  engravers 
in  etching. 

Hatchment,  in  heraldry,  an  armorial 
escutcheon  placed  over  a  door  in 
memory  of  a  deceased  person  of 
rank 

Hatchways,  places  in  the  middle  of 
the  decks  of  a  vessel,  for  the  con- 
venience of  lowering  down  goods 

Haul  the  wind,  in  navigation ;  to  direct 
the  ship's  course  nearer  to  the 
point  of  the  compass  from  which 
the  vTind  blovra 

Haunch  of  an  arch,  the  part  between 
the  vertex  and  the  springing 

Hawse,  in  navigation,  the  situation  of 
the  cables  before  the  ship's  stem 
when  she  is  moored  with  two  an- 
chors forward  from  the  starboard 
and  larboard  bow 

Hawse-pieces,  the  timbers  in  the  bow 
of  a  ship  whose  sides  are  nearly 
parallel  to  the  middle  line 

Hawthorn,  a  wood  not  much  used,  is 
hard,  and  of  a  whitish  colour,  vidth 
a  tinge  of  yellow 

Hazel,  a  small  underwood  which  is 
very  elastic,  used  for  turning,  for 
the  handles  of  blacksmiths'  chisels, 
for  the  hoops  of  casks,  &c. 

Head-ledges,  the  thwartship  pieces 
which  frame  the  hatch -ways  or 
ladder-ways  of  ships 

Head-stocks,  the  frames  which  sup- 
port the  centres  of  a  lathe;  viz. 
the  mandril-frame  and  the  poppet- 
head,  or  back  centre  frame 

Health  of  Towns,  a  phrase  recently 
coined  to  expressthegeneral  purpose 
ofpublic  sanatory  measures.  These 
measures  are  based  upon  the  prin- 
ciples  of  animal  physiology,  but 


HEA 


had  been  recognized  only  in  the 
curative  policy  of  the  physician, 
until  the  evils  of  their  neglect  were 
traced  by  statistical  inquiries  into 
the  causes  of  disease ;  and  they  are 
therefore  now  properly  regarded  as 
essential  objects  in  the  social  eco- 
nomy of  life. 

The  human  constitution  is  so 
formed  that  its  health  depends  on 
an  adequate  supply  of  pure  air, 
water,  and  light.  Every  circum- 
stance, therefore,  which  vitiates  the 
quality,  or  reduces  the  due  quan- 
tity, of  these  essentials,  is  injurious 
to  health,  and  demands  amendment 
or  extinction. 

Thus  the  efficient  supply  of  pure 
and  attemperated  air  requires  pro- 
per drainage  and  ventilation,  warm- 
ing or  cooling  of  all  places  in  which 
human  beings  live  or  congregate : 
it  also  limits  the  minimum  of  size 
for  the  healthy  habitations  of  men. 

The  plentiful  supply  of  pure  wa- 
ter necessitates  suitable  provision 
for  obtaining  and  treating  it,  and 
the  proscription  of  all  arrangements 
which  limit  the  service  or  injure  its 
purity.  Equally  important  with 
these  conditions  is  the  third  one 
enumerated,  which  suggests  the  ne- 
cessity of  so  arranging  and  con- 
structing streets  and  buildings,  that 
abundance  of  light  may  at  idl  times 
be  admitted  into  them. 

As  measures  auxiliary  to  these 
objects,  and  of  great  importance  in 
the  combined  arrangements  of  so- 
ciety, public  exercising  and  plea- 
sure grounds,  baths  and  wash- 
houses,  cooking  apparatus,  medical 
and  remedial  establishments,  street 
accommodations,  &c.,  command 
adoption,  and,  when  adequately 
carried  out,  will  tend  to  complete 
the  physical  requisites  of  the  health 
of  towns. 
Heatf  in  the  ordinary  application  of 
the  word,  signifies,  or  rather  im- 
plies, the  sensation  experienced 
upon  touching  a  body  hotter,  or 
of  a  higher  temperature,  than 
the  part  or  parts  which  we  bring 

216 


HEAT.  HEA 

into  contact  with  it:  in  another 
sense,  it  is  used  to  express  the 
cause  of  that  sensation.  To  avoid 
any  ambiguity  that  may  arise  from 
this  double  use  of  the  same  expres- 
sion, it  is  usual  and  proper  to  em- 
ploy the  word  caloric  to  signify  the 
principle  or  cause  of  the  sensation 
of  heat.  On  touching  a  hot  body, 
caloric  passes  from  it,  and  excites 
the  feeling  of  warmth:  when  we 
touch  a  body  having  a  lower  tem- 
perature than  our  hand,  caloric 
passes  from  the  hand  to  it,  and 
thus  arises  the  sensation  of  cold. 

Caloric  is  usually  treated  of  as 
if  it  were  a  material  substance; 
but,like  light  and  electricity,its  true 
nature  has  yet  to  be  determined. 

COMMUNICATION  OF  CALORIC. 

Caloric  passes  through  different 
bodies  with  different  degrees  of  ve- 
locity. This  has  led  to  the  division 
of  bodies  intQ  conductors  and  non- 
conductors of  caloric :  the  former 
includes  such  bodies  as  metals, 
which  allow  caloric  to  pass  freely 
through  their  substance;  and  the 
latter  comprises  those  that  do  not 
give  an  easy  passage  to  it,  such  as 
stones,  glass,  wood,  charcoal,  &c. 
TaJ)le  of  the  relative  conducting 

power  of  different  bodies. 


Platinum  . 

•            •       xvvu 

.       981 

SUver 

.      973 

Copper 

.      898 

Iron  . 

.      374 

Zinc . 

.      363 

Tin    . 

.      304 

Lead 

.       180 

Marble      . 

24 

Porcelain  . 

12-2 

Fire-brick  . 

11 

Fire-clay    . 

11-4 

With  Water  as 

the  standard. 

Water 

10 

Pine  . 

39 

Lime 

39 

Oak  . 

33 

Elm  . 

32 

Ash  . 

31 

Apple 

28 

Ebony 

22 

HEA 


HEIGHT  OF  COLUMNS. 


H£I 


Relative  eomdueting  power  of  d^" 
fereni  eubetancei  eon^ared  with 
each  other. 


Hares'  far 

1-315 

EideT'-down 

1-305 

Beayers'  for 

1-296 

Raw  silk  . 

1-284 

Wool 

1-118 

Lamp.black 
Cotton      . 

1117 
1-046 

Lint 

1032 

Charcoal  • 

•937 

Ashes  (wood) 
Sewing  silk 
Air  . 

•927 
•917 
•576 

Betatwe  conducting  pow€ 
Mercury    • 
Water 

roffiuids, 

1-000 

•357 

Proof  Spirit 
Alcohol  (pure) 

•  • 

•  • 

•312 
•232 

RADIATION  OF  CALORIC. 

When  heated  bodies  are  exposed 
to  the  air,  they  lose  portions  of 
their  heat,  by  projection  in  right 
lines  into  space,  from  all  parts  of 
their  surface. 

Bodies  which  radiate  heat  best, 
absorb  it  best. 

Radiation  is  affected  by  the  na- 
ture of  the  surface  of  the  body; 
thus  black  and  rough  surfaces  ra- 
diate and  absorb  more  heat  than 
light  and  polished  surfaces. 

Table  qf  the  radiating  power  qf 


Water      . 

100 

Lamp-black 

100 

Writing-paper  . 

100 

Ghiss 

90 

Indian  ink 

88 

Bright  lead      . 

19 

Silver 

12 

Blackened  tin  . 

100 

Clean         do.  . 

12 

Scraped     do.  . 

16 

Ice           .        .        . 

85 

Mercury  . 

20 

Polished  iron   • 

15 

Copper    . 

12 

Professor  Leslie  has  proved,  by  a 
variety  of  experiments,  that  the 
heat  which  is  propagated  by  radi- 
ation from  different  bodies  varies 

"217 


with  the  nature  of  their  external 
sorfiiuies ;  the  quantity  which  flows 
in  a  given  timp  from  a  body  with  a 
polished  surface  being  much  less 
than  would  flow  from  the  same 
body  with  a  rou(^  surface.  It 
therefore  follows  that  the  external 
surfaces  of  the  steam-pipes  of  steam 
engines  and  steam  cylinders  should 
be  as  smooth  as  possible,  and  should 
be  covered  with  any  body  which  is 
a  bad  conductor  of  heat 

Heel  tool,  a  tool  used  by  turners  for 
roughing  out  a  piece  of  iron,  or  turn- 
ing  it  to  somewhat  near  the  intend- 
ed size :  it  has  a  very  acute  cutting 
edge  and  an  angular  base  or  heel 

Height  qfcohtnuu.  The  height  of  a 
column  is  measured  by  its  diameter 
immediately  above  the  base. 

Diameten  high. 
The  Tuscan  column         .    7 
The  Ionic        .        .        .9 
Corinthian  and  Composite  10 
In  the  above  heights  are  included 
the  capitals  and  bases,  which  are 
esteemed  parts  of  the  columns  with 
which  they  are  used. 
Heighte  and  Distances,  Trigonometry 
receives  its  principal  practical  ap- 
plication in  the  operations  of  sur- 
veying, and  measuring  heights  and 
distances;  as,  however,  the  methods 
of  its  application  (depending  on  the 
peculiar  circumstances  of  each  case)  ^ 
are  exceedingly  various,  no  general 
rules  can  be  specified. 

The  instruments  employed  to 
measure  angles  are  quadrants,  sex- 
tants, theodolites,  &c.,  the  use  of 
either  of  which  may  be  sooner 
learned  from  an  examination  of  the 
instruments  themselves  than  from 
any  description  independently  of 
them.  For  military  men  and  for 
civil  engineers,  a  good  pocket  sex- 
tant and  an  accurate  micrometer 
(such  as  Cavallo's),  attached  to  a 
telescope,  are  highly  usefiiL  For 
measuring  small  distances,  as  bases, 
50-feet  and  100-feet  chains,  and  a 
portable  box  of  graduated  tape, 
'  will  be  necessary. 

For  the  purposes  of  surveying,  it 


HEL 


HERALDRY. 


HIN 


is  usual  to  employ  a  chain  66  feet 
in  length,  suhdiidded  into  100  links, 
each  7*92  inches:  the  reason  for 
using  a  chain  of  this  length  is,  that 
ten  of  such  square  chains  are  equal 
to  an  acre,  and  therefore  the  acre- 
age of  the  several  divisions  of  an 
estate  is  found  with  much  greater 
facility  when  measured  in  chains 
and  links,  than  when  the  measure- 
ments are  taken  in  feet. 
HeliXf  the  small  volute  under  the 

ahacus  of  a  Corinthian  capital 
HeliXt  any  thing  of  a  spiral  form,  whe- 
ther in  one  plane,  as  the  spiral 
curve,  or  in  different  planes,  as  the 
screw 
Heptagon^  in  geometry,  a  figure  with 

seven  sides  or  angles 
Heraldry  is  a  science  intimately  con- 
nected with  the  early  history  of 
Europe,  its  chivalry,  its  conquests, 
and  the  hearing  of  arms :  it  teaches 
how  to  blazon  or  explain  in  proper 
terms  all  that  belongs  to  arms; 
and  how  to  marshal  or  dispose 
with  extreme  punctualness  divers 
arms  on  a  field.  It  is  in  its  archae- 
ology and  in  precedent  indisputable. 
It  teaches  whatever  relates  to  the 
marshalling  of  solemn  processions 
and  other  public  ceremonies,  at  co- 
ronations,installations  of  Knights  of 
the  Garter,  Knights  Grand  Cross  of 
the  Bath,  Knights  Companions,  &c.; 
at  the  creation  of  peers,  nuptials, 
christenings  of  princes,  funerals,  &c 
It  is,  in  fact,  an  important  science, 
particularly  in  English  history,  in 
tracing  the  narrative  of  the  families 
of  the  nobility  and  commoners, 
their  holdings,  their  distinguishing 
qualifications,  in  arms,  in  literature, 
and  in  the  arts. 
HemuBj  statues  of  which  only  the 
head  is  carved,  and  sometimes  a 
portion  of  the  bust :  square  or  cu- 
bical figures  of  the  god  Mercury, 
without  legs  and  arms,  anciently 
placed  by  the  Greeks  and  Romans 
at  their  cross-ways 
Herring-bone  wori,  masonry  in  which 
the  stones  are  laid  aslant  instead 
of  being  bedded  flat 

218  '-  " 


/f«r«e,  a  portcullis ;  a  frame  whereon 
lighted  candles  were  placed  at  the 
obsequies  of  distinguished  persons 

Heterogemout,  opposite  or  diiwimilar 
in  nature,  as  opposed  to  homogene- 
ous 

Hewtu,  in  Cornwall,  the  sides  of  t 
calciner  or  buming-house  furnace ; 
so  called  from  their  being  formerly 
built  with  hewn  moor-stone 

Hexagon^  in  geometry,  a  figure  of  six 
sides  or  angles 

Hexahedron^  in  geometry,  one  of  the 
five  regular  solids,  being  the  same 
with  a  cube 

Hexastglet  a  portico  of  six  colnmns  in 
front 

HexastgJot,  a  frontage  of  six  columns 

HexereSf  a  vessel  vdth  six  banks  of 
oars  on  each  side 

HiatiUf  an  aperture,  a  breach  or  de- 
fect 

Hick*8  mandril,  an  arbor  for  turning 
rings :  at  the  centre  of  the  arbor 
there  is  a  cone,  round  which,  at 
equal  distances,  wedges  are  fitted 
into  dove-tailed  grooves,  and  are 
expanded  to  the  bore  of  the  ring 
by  a  nut  acting  on  a  screw  at  the 
end  of  the  cone 

Hickory  t  or  white  tpahmtf  a  native  of 
America.  The  wood  of  the  young 
trees  is  exceedingly  tough  and  flex- 
ible, and  makes  exceUent  hand- 
spikes, &C. 

Hieroglyphic,  an  emblem,  a  figure  by 
which  a  word  is  implied;  the 
Egyptian  art  of  writing  in  picture 

High-pressure  engine,  a  non-conden- 
sing steam  engine,  worked  by  the 
excess  of  the  pressure  of  the  steam 
upon  the  piston  above  the  pressure 
of  the  atmosphere :  in  this  engine, 
after  the  steam  has  acted  upon  the 
piston,  it  passes  through  the  educ- 
tion-pipe into  the  air 

HiHng,  the  covering  or  roof  of  a  buUd- 

ing 

Hinges,  the  joints  on  which  doors, 
gates,  &c.,  turn 

Hinges.  The  diversity  of  forms  into 
which  door  furniture  has  been  re- 
solved i»  almost  endless.  Many  of 
the  ancient  hinges  were  not  only 


HIP 


HORSE-POWER. 


HOR 


'wtonght  into  scrolls  and  other  flo- 
rid devices*  but  occasionally  further 
enriched  with  inscriptions. 
Hip,  the  external  angle  formed  by  the 
meeting  of  the  sloping  sides  of  roofs 
which  have  theirwall-platesmnmng 
in  different  directions 
H^'ienodf  a  pinnade,  finial,  or  other 
«imii«r   ornament,  placed  on  the 
top  of  the  hips  of  a  roof  or  the 
point  of  a  gable 
Hytpodromef  a  large  plot  of  ground 
laid  out  for  the  exercise  of  horses ; 
among  the  Greeks,  a  race-course 
Hoggan,  in  Cornish,  a  hawthorn-berry, 

the  tinner's  pasty 
Hogging f  in  ship-building,  the  convex 
appearance  resembling  the  back  of 
a  hog,  given  to  a  ship  after  being 
first  launched,  by  the  dropping  of 
the  two  extremities 
Hogshead,  a  measure  of  63  gallons 
Hoi8t,  an  apparatus  for  raising  bodies 
from  the  ground  floor  of  a  building 
to  a  floor  above 
HoUaw  newellj  an  opening  in  the  mid- 
dle of  a  staircase,  the  steps  only 
being  supported  at  one  end  by  the 
surroundOng  wall,  the  ends  next  the 
hollow  unsupported;  also  a  hollow 
groin,  pier,  of  brick  or  stone,  made 
behind  the  lock-gates  of  canals 
HoUy  is   a  very  clean,  flne-grained 
wood,  the  whitest  and  most  costly 
of  those  used  by  the  Tunbridge- 
ware  manufacturers :  it  is  used  for 
painted  screens  and  a  great  variety 
of  fancy  and  tasteful  purposes 
Hofy-water  vessel,  the  vessel  which 
contains  the  consecrated  or  holy 
water  carried  in  religious  proces- 
sions :  also  the  receptacle  for  holy 
water  placed  at  the  entrances  of 
Roman  Catholic  churches 
Holy -water  stone,  the  stoup  on  which 

the  h<^y -water  vessel  is  placed 
HomestaU  or  Homestead,  a  mansion, 
honse,  or  seat  in  the  coimtry;  a 
farm,  with  the  land  a^jouung 
Homogeneous,  a  term  applied  to  va- 
rious  substances,  to  denote  that 
they  consist  of  similar  parts,  or 
parts  of  the  same  nature  and  kind 
Hoodings^ends,  the  ends  of  planks 

■ — • 

219 


which  flt  into  the  rabbets  of  the 
stem  and  stem-post  of  a  ship 

Hood-mmUd,  a  band  or  string  over 
the  head  of  a  door,  window,  or 
other  opening,  in  an  andetot  build- 
ing; so  called  from  its  enclosing, 
as  within  a  hood,  the  inferior  mould- 
ings and  the  opening  itself 

Hood-moulding,  a  name  given  to  the 
label-moulchng 

Hornbeam,  a  very  toug^  and  stringy 
European  wood,  usedbynullwrights 
for  the  cogs  of  wheels,  also  for 
plumbers'  dressers,  or  mallets,  &c. 

Hornblende,  a  conspicuous  ingredient 
in  the  composition  of  rocks,  divided 
into  common  hornblende,  horn- 
blende-schist, and  basaltic  horn- 
blende 

Hom-stonst  a  conchoidal  and  silidous 
mineral  substance,  allied  in  compo- 
sition to  flint,  but  of  a  more  earthy 
texture 

Horologium,  a  ni|me  andently  given  to 
any  instrument  for  measuring  time 

Horse,  a  large  round  bar  of  iron  fixed 
in  the  head  of  a  ship 

Horse,  in  navigation,  the  name  of  a 
rope  reaching  from  the  middle  of  a 
yard  to  its  extremity,  on  which  the 
sailors  stand  when  they  are  loosing 
or  reefing  the  sails 

Horse-chestnut  wood  is  one  of  the 
white  woods  used  by  the  Tunbridge 
turners ;  it  is  close  and  soft,  even 
in  the  grain,  and  is  much  used  for 
brush-backs,  &c 

Horse-power.  Although  horses  are 
not  all  of  one  strength,  yet  there  is 
a  certain  force  now  generally  agreed 
upon  among  those  who  construct 
steam  engines,  which  force  is  de- 
nominated a  horse's  power,  and 
hence  steam  engines  are  distin- 
guished in  size  by  the  number  of 
horses'  power  to  which  they  are 
said  to  be  equal. 

The  measure  of  a  mechanical 
effect  equal  to  a  horse's  power  has 
been  much  dLsputed:  this,  however, 
can  be  but  a  matter  of  httle  conse- 
quence, if  the  measure  be  generally 
imderstood,  since  there  is  no  such 
thing  as  bringing  it  into  any  real 


HOR 


HOT-AIR  BLAST. 


HOT 


measure.  Some  horses  will  perfonn 
double  the  work  of  others,  and  those 
of  one  country  will  work  more  than 
those  of  another.  DesaguUers' mea- 
sure is,  that  a  horse  will  walk  at  the 
rate  of  2i  miles  per  hour,  against 
a  resistance  of  200  ibs.,  and  this 
gives,  as  a  number  for  comparison, 
44,000 ;  that  is,  the  raising  of  lib. 
44,000  feet  in  a  minute,  or,  what 
amounts  to  the  same,  the  raising 
of  44,000  lbs.  1  foot  in  a  minute. 

Emerson's  measure  is  the  same 
as  DesaguliersS  and  Smeaton's  re- 
sult is  22,916  tbs.  under  the  same 
circumstances. 

James  Watt  found  from  repeated 
experiments,  that  33,000  fts.  1  foot 
per  minute  was  the  average  value 
of  a  horse's  power;  but  his  engines 
were  calculated  to  work  equal  to 
44,000  ibs.  1  foot  per  minute. 

H.  P.,  the  abbreviation  for  horse- 
power 

HorttUf  a  garden  or  a  pleasure-ground 

Hose-pipeSf  in  locomotive  engines, 
elastic  pipes  made  of  canvas,  satu- 
rated with  a  solution  of  Indian  rub- 
ber, sometimes  galvanized,  and 
forming  a  good  elastic  connection 
between  the  engine  and  tender  feed- 
pipes. They  are  now  generally  used 
in  preference  to  ball  and  socket 
connections  for  conveying  the  steam 
to  the  tender. 

Hospitaliat  anciently  the  doorways  in 
the  scene  of  a  theatre  on  the  right 
and  left  of  the  valvse  regiae  or  prin- 
cipal doorway;  so  called  because  the 
moveable  scenes,  representing  inns 
or  places  appropriated  for  the  recep- 
tion of  strangers,  were  placed  near 
them 

Hospitals  were  originally  designed  for 
the  relief  of  poor  and  impotent  per- 
sons, and  the  entertainment  of  tra- 
vellers upon  the  road,  particularly 
of  pilgrims,  and  therefore  they 
were  generally  built  upon  the  road- 
side ;  in  later  time  they  have  always 
been  founded  for  fixed  inhabitants : 
before  the  spoliation,  there  existed 
in  England  above  358  of  these 
houses  of  relief  , 

220 


Hostelry  or  Hostry,  anciently  an  inn 
Hot-air  blast*  It  was  concdyed  that 
the  presence  of  sulphur  in  the  air 
was  the  cause  of  blast  furnaces 
working  irregularly,  and  making 
bad  iron  in  the  summer  months. 
Subsequently  it  was  stated  that  one 
Of  the  Muirkirk  iron  fmnaces,  in 
Scotland,  situated  at  a  considerable 
distance  from  the  engine,  did  not 
work  so  well  as  the  others,  which 
led  to  the  conjecturo  that  the  fric- 
tion of  the  air,  in  passing  along  the 
pipe,  prevented  an  eqcud  Tolome 
of  the  air  getting  to  the  distant 
furnace  as  to  the  one  which  was 
situated  close  by  the  engine :  it  was 
considered  also,  that  by  heating  the 
air  at  the  distant  furnace,  its  Yolume 
would  increase  in  the  ratio  of  the 
known  law,  that  air  and  gases  ex- 
pand to  double  their  bulk  at  448'' 
temperaturo. 

Example:  If  1000  cubic  feet, 
say  at  50°  of  Fahronheit,  were 
pressed  by  the  engine  in  a  given 
time,  and  heated  to  600''  of  Fah- 
ronheit, it  would  then  be  increased 
in  volume  to  2104*4,  and  so  on  for 
every  thousand  feet  that  would  he 
blown  into  the  furnace.  In  prose- 
cuting the  experiments  which  this 
idea  suggested,  circumstances,how- 
ever,  became  apparent  which  in- 
duced a  belief,  that  heating  the  air 
introduced  for  supporting  combus- 
tion into  air  furnaces  materially  in- 
creased its  efficiency  in  this  respect ; 
and  with  the  view  of  putting  these 
suspicions  to  the  test,  the  following 
experiments  were  made. 

To  the  nozzle  of  a  pair  of  common 
smith's  bellows,  a  cast-iron  vessel 
heated  is  attached  from  beneath,  in 
the  manner  of  a  retort  for  gene- 
rating gas,  and  to  this  Tcssel  the 
blow-pipe,  by  which  the  forge  or 
fiumace  was  blown,  was  also  at- 
tached. The  air  from  the  bellows 
having  thus  to  pass  through  the 
heated  vessel  above  mentioned,  was 
consequently  heated  to  a  high  tem- 
perature  before  it  entered  the  forge 
fire,  and  the  result  produced,  in 


HOT 


HOUSE. 


HOU 


increasing  the  intensity  of  the  heat 
in  the  furnace,  was  far  beyond  ex- 
pectation, and  so  evident  as  to  make 
apparent  the  fallacy  of  the  generally 
received  opinion,  that  the  coldness 
of  the  air  of  the  atmosphere  in  the 
winter  months  was  the  caase  of  the 
best  iron  being  then  produced. 

In  overthrowing  the  old  theory, 
new  principles  in  the  process  of 
iron-making  were  established. 

Experiments  on  the  large  scale, 
to  reduce  iron  ore  in  a  founder's 
cupola,  were  commenced  at  the 
Clyde  Iron  Works.  These  experi- 
ments were  completely  successfid, 
and  in  consequence  the  invention 
was  immediately  adopted  at  the 
Calder  Ironworks,  where  the  blast, 
being  made  to  pass  through  two 
retorts  placed  on  each  side  of  one 
of  the  large  furnaces  before  entering 
the  furnace,  eflfected  an  instanta- 
neous change,  both  in  the  quantity 
and  quality  of  iron  produced,  and  a 
considerable  saving  of  fuel 

The  whole  of  the  furnaces  at  the 
Calder  and  Clyde  Ironworks  were 
filled  up  on  the  principle  of  the  hot 
blast,  and  its  use  at  these  works 
continues  to  be  attended  with  the 
utmost  success;  it  has  also  been 
adopted  at  Wilsontown  and  Gart- 
shirrie  Iron  Works  in  Scotland,  and 
at  several  works  in  England  and 
Rrance. 

The  air  as  at  first  raised  to  250^ 
of  Fahrenheit  produced  a  saving  of 
three-sevenths  in  every  ton  of  pig 
iron  made,  and  the  heating  appa- 
fitus  having  since  been  enliurged,  so 
as  to  increase  the  temperature  of 
the  blast  to  600''  Fahrenheit  and 
upwards,  a  proportional  saving  of 
fuel  is  effected;  and  an  immense 
additional  saving  is  also  acquired 
by  the  use  of  raw  coal  instead  of 
coke,  which  may  now  be  adopted. 
By  thus  increasing  the  heat  ot  the 
blast,  the  whole  waste  incurred  in 
burning  the  coalinto  coke  is  avoided 
in  the  process  of  making  iron. 

By  the  use  of  this  invention,  with 
three-sevenths  of  the  fuel  formerly 

221 


employed  in  the  cold- air  process, 
the  iron-maker  is  now  enabled  to 
make  one-third  more  iron  of  a 
superior  quality. 

Were  the  hot  blast  generally 
adopted,  the  saving  to  the  country 
in  the  article  of  coal  would  be 
immense.  In  Britain,  about  700,000 
tons  of  iron  are  made  annually,  of 
which  50,000  tons  only  are  pro- 
duced in  Scotland:  on  these  50,000 
tons  would  be  saved,  in  the  process 
of  manufacture,  200,000  tons  of 
coal  annually.  In  England  the 
saving  would  be  in  proportion  to 
the  strength  and  quaUty  of  the 
coal,  and  cannot  be  computed  at 
less  than  1,520,000  tons  annually ; 
and  taking  the  price  of  coals  at  the 
low  rate  of  four  shillings  per  ton,  a 
yearly  saving  of  £  296,000  sterling 
would  be  effected. 

Nor  are  the  advantages  of  this 
invention  solely  confined  to  iron- 
making  :  by  its  use  the  founder  can 
cast  into  roods  an  equal  quantity 
of  Iron  in  much  less  time,  and  with 
a  saving  of  nearly  half  the  fuel 
employed  in  the  cold-air  process ; 
and  the  blacksmith  can  produce  in 
the  same  time  one-third  more  work, 
with  mudi  less  fuel  than  he  for- 
merly required. 

In  all  the  processes  of  metallur- 
gical science  it  vrill  be  found  of  the 
utmost  importance  in  reducing  the 
ores  to  a  metallic  state. 

Hot-water  punyf,  the  feed-pump  of  a 
condensing  engine,  for  supplying 
the  boiler  from  the  hot  well 

Hot  weB,  the  vessel  which  receives 
the  water  from  the  air-pump 

Hour-gkttg  standi  a  bracket  or  frame 
of  iron  for  receiving  the  hour-glass. 
See  *  Papers  on  Architecture,"  vol. 
iii.,  which  contains  a  good  example. 
*<  By  the  side  of  the  pulpit  stiU 
remains  the  ancient  hour-glass  and 
frame." 

J7ouM,  a  place  of  residence.  The  pur- 
pose  of  a  house  bemg  for  dwelhng, 
and  that  of  tents  being  the  same, 
they  are  called  by  one  name  in  the 
Hebrew;  on  the  same  principle,  the 


HOU 


HOUSES. 


HOU 


Tabernacle  of  God,  though  only  a 
tent,  is  sometimes  called  the  Tem- 
ple, that  is,  the  residence  of  God. 
The  ordinary  buildings  or  houses 
in  the  East  haye  continued  the  same 
from  the  earliest  ages,  without  the 
least  alteration  or  improTcment ; — 
large  doors,  spacious  chambers, 
marble  pavements, cloisteredcourts, 
with  fountains,  &c., — conyeniences 
well  adapted  to  the  circumstances 
of  these  climates,  where  the  summer 
heats  are  generally  intense.  The 
streets  of  these  cities,  the  better  to 
shade  them  from  the  son,  are  usu- 
ally narrow,  with  sometimes  a  range 
of  shops  on  each  side.  On  enter- 
ing one  of  the  principal  houses,  a 
porch  or  gateway  will  first  be  seen, 
with  benches  on  each  side,  where 
the  master  of  the  family  receives 
visits  and  dispatches  business.  In 
houses  of  better  fashion,  the  cham- 
bers are  hung  with  velvet  or 
damask  from  the  middle  of  the 
wall  downwards,  and  covered  and 
adorned  mth  velvet  or  damask 
hangings  of  white,  blue,  red,  green, 
or  other  colours.  The  ceiling  is 
generally  of  wainscot,  either  very 
artistically  painted,  or  else  thrown 
into  a  variety  of  panels  with  gilded 
mouldings,  and  with  scrolls  of  the 
Koran,  &c.  The  stairs  are  some- 
times placed  in  the  porch,  some- 
times at  the  entrance  into  the  court. 
When  there  is  one  or  more  stories, 
they  are  afterwards  continued, 
through  one  comer  or  other  of  the 
gallery,  to  the  top  of  the  house, 
whither  they  conduct  through  a 
door  that  is  generally  kept  shut, 
to  prevent  their  domestic  animals 
from  daubing  the  terrace,  and 
thereby  spoiling  the  water  which 
falls  from  thence  into  the  cisterns 
below  the  court,  &c.  Such  in 
general  are  the  manner  and  contri- 
vances of  the  Eastern  houses ;  and 
if  it  may  be  presumed  that  our 
Saviour,  at  the  healing  of  the  para- 
lytic, was  preaching  in  a  house  of 
this  fashion,  it  may,  by  attending 
only  to  the  structure  of  it,  throw 

222 


some  light  on  one  circumstance  of 
that  history,  which  has  given  great 
offence  to  some  unbelievers.  The 
houses  of  the  poorer  class  of  people 
in  the  Bast  are  of  very  bad  con- 
struction, oonststiBg  of  mod  vnlla, 
reeds,  and  rushes.  In  Constanti- 
nople every  thing  is  sacrificed  to 
outside  decorative  show:  built  prin- 
cipally of  wood,  conflagrations  are 
frequent  and  extensive.  In  earlier 
history,  magnificence  and  refined 
luxury  were  combined  with  the 
highest  and  most  noble  examples  of 
decorative  art.  The  interior  of  the 
domestic  residences  and  public  edi- 
fices of  Herculaneum  and  Pompeii 
surpassed  every  existing  example. 
The  houses  of  the  Roman  citizens 
partook  also  of  the  refinement  of 
an  age  of  art ;  and  modem  Europe 
has  noble  examples  of  domestic 
dwellings,  coeval  with  the  wealth 
of  the  country  in  which  they  are 
still  to  be  found.  In  England,  the 
domestic  residence  of  the  noble- 
man, the  merchant,  and  the  trader 
are,  besides  the  elegances  of  their 
arrangements,  models  of  comfort 
and  health. 

Hou9€8,  Before  a  house  is  planned, 
the  proprietor  should  describe  the 
kind  of  house  he  wishes  to  be  built. 
The  architect  is  to  consider  what 
must  be  had,  and  what  may  be  dis- 
pensed with.  He  ought  to  keep 
his  plan  as  scrapulously  vrithin  the 
expense  proposed,  as  within  the 
limits  of  the  ground  he  is  to  build 
upon ;  he  is,  in  short,  to  enter  into 
the  views,  the  wishes,  and  the  ideas 
of  the  gentleman  who  will  inhabit 
the  house  proposed  to  be  erected. 

Homes  suitable  to  the  different  ranks 
of  the  community. — ^Vitravius  in- 
structs us  of  those  parts  of  priyate 
houses  which  are  exclusively  appro- 
priated to  individuals  of  the  family, 
and  in  what  manner  these  ought  to 
be  connected  with  the  apartments 
into  which  strangers  are  admitted; 
for  there  are  several  parts  of  a  house 
which  may  not  be  approached  by 
those  who  are  not  of  the  household. 


HOU 


HYDRAULIC  BELT. 


HYD 


nnlesB  expressly  invited;  such  as  the 
sleeping-roomSy  triclinia,  baths,  and 
those  apartments  which  are  in 
general  use.  The  parts  which  are 
accessible  to  all,  and  into  which 
any  person  may  enter  uninyited, 
are  the  vestibule,  caysediom,  peri- 
style, and  whatever  others  are  built 
for  similar  purposes. 
Hovues.  Ofthe  proportions  of  private 
houses,  Vitruvius  says, — "  Nothing 
ought  to  engage  the  attention  of 
an  architect  more  than  the  pro- 
portions of  all  the  parts  in  the 
houses  lie  constructs :  after  having 
determined  upon  such  proportions 
as  the  necessity  for  the  commen- 
suration  of  the  parts  with  the  entire 
building  seems  to  require,  the  great- 
est judgment  must  be  exercised  in 
adapting  them  to  the  nature  of  the 
spot,  the  use  to  which  the  edifices 
are  designed,  and  the  appearance 
they  ought  to  assume;  and  this 
must  be  done  by  making  such  addi- 
tions or  deductions,  that,  although 
the  proportions  are  not  strictly  what 
they  ought  to  be,  the  eye  may  not 
be  conscious  wherein  they  fail.  The 
same  objects  appear  differently 
xmder  dissimilar  circumstances ;  li 
near  the  ground  or  at  a  considerable 
elevation ;  if  in  a  confined  space  or 
an  exposed  situation.  Under  every 
peculiar  circumstance,  great  judg- 
ment is  necessary  in  odculating  the 
effect  which  will  be  ultimately  pro- 
duced. The  impression  made  upon 
the  sense  of  seeing  is  not  always 
a  correct  image  of  the  object ;  for, 
in  painting,  columns,  mutules,  and 
statues  are  made  to  appear  pro- 
jecting and  detached,  when,  in  fact, 
every  object  represented  is  in  one 
and  the  same  place.  It  becomes 
necessary,  in  the  first  place,  to  in- 
stitute laws  of  proportion,  upon 
which  all  our  calculations  must  be 
founded.  According  to  these,  the 
ground-plan,  exhibiting  the  length 
and  breadth  of  the  whole  work 
and  the  several  parts  of  it,  must  be 
formed.  When  the  magmtude  of 
these  is  once  determined,  the  parts 

223 


must  be  arranged  so  as  to  produce 
that  external  beauty  which  suffers 
no  doubt  to  arise  in  the  minds  of 
those  who  examine  it  as  to  the 
want  of  proportion  in  any  part/' 

Houseg  qf  the  Qreeks, — The  Greeks 
had  a  different  way  of  building  from 
the  Romans ;  for,  as  Vitruvius  says, 
''instead  of  making  porticoes  or 
galleries  and  halls,  they  made  the 
entry  to  their  houses  very  narrow, 
placing  on  one  side  the  stables,  and 
the  porter's  lodge  on  the  other. 
From  this  first  entry  one  passed 
into  a  court,  which  had  piazzas  on 
three  sides,  and  towards  that  of 
the  south  they  made  anti,  or  abut- 
ments of  pilasters,  which  supported 
the  joists  of  the  ceiling  more  in- 
wards ;  because  that  leaving  some 
space  between  the  one  and  the 
other,  they  had  very  large  places, 
whidi  they  appointed  for  lodging 
to  the  mistress  of  the  house,  and 
to  the  men  and  women  servants. 
On  the  same  floor  with  these  abut- 
ments there  were  some  rooms  which 
maybe  called  ante-chambers,  cham- 
bers and  drawing-rooms,  being 
every  one  just  behind  the  other." 

Housing,  a  tabernacle,  or  niche  for  a 
statue,  was  formerly  so  called 

Huelf  a  work,  a  mine,  as  huel  stones, 
a  tin  mine 

HuUt,  in  Cornwall,  an  old  excavated 
working ;  *  to  hulk  the  lode  * 

Hulk  or  htdl,  the  body  of  a  ship 

Hungarian  machmey  an  hydrauHc  en- 
gine, a  very  ingenious  application 
ofthe  l^txojet-d^eau  principle 

Hydraletest  according  to  Strabo,  a 
mill  for  grinding  com  by  water- 
power 

Hydraulic  belt,  an  endless  double 
band  of  woollen  doth,  passing  over 
two  rollers,  the  lower  part  of  the 
belt  being  immersed  in  water :  it  is 
driven  with  a  velodty  of  not  less 
than  a  thousand  feet  per  minute, 
and  the  water  contained  between 
the  two  surfaces  is  carried  up  and 
discharged,  as  it  passes  over  the 
upper  roller,  by  the  pressure  of  the 
band 


HYDKOSTATIC  PRESS. 


HYD 


■  mMhine  contrived 


Hydraukei.  The  tdcace  of  hrdnulici 
teaches  the  method  of  eitiiiiatiiig 
the  iwiftoeu  and  force  of  fluidi  In 
motion.  The  icience  ii  di^nided 
bf  the  name  of  hTdrodynamica,  or 
the  application  of  d^amici  to  the 
impulsion  and  flon  of  water  and 
other  liquids,  u  nell  as  the  forces 
Kith  which  they  act  upon  bodies 
against  which  the;  strike,  or  which 

Hydrodytutmict,  the  sdeace  of  the 
laws  of  the  motion  of  fluidi,  con- 
sisting of  two  broDchea.  The 
science  of  h;draiiliea  refers  prind- 
paUf  to  the  machlner;  for  conduct- 
ii^;  fluids ;  that  of  hydrostatics, 
to  the  pressure,  cquilibnom,  and 
cohesion  of  fluids. 

Hydrogen.  'Hjixofsea  gaa  is  com. 
moiUf  obtained  for  experimental 
purposes  b;  tlie  decomposition  of 
water;  its  name  is  deiived  &om 
the  Greek  words  meaning  water 
and  to  gmerate. 

Hydrometer,  an  instnunent  for  mea- 
suring the  tpedSc  graiitj  of  Tarioos 
spirits  and  other  liquids,  by  floating 


Hydrotci^e,  an  instrument  intended 
to  mark  the  presence  of  water  in  air 

Hydrotiatie  or  HydrauUe  preu,  a 
machine  adapted  for  acquiring  great 
prasaure  in  cues  where  little  mo- 
tion is  required.  The  contrivance 
d  this  apparatus  is  due  to  tlie  ce- 
lebrated mechanidan,  Joseph  Bra- 
mah,  «bo  obtained  a  patent  for  it 
on  the  31st  of  March,  1796,  under 
tiie  title  of  ■  certain  new  methods 
of  producing  and  applying  a  more 
considerable  degree  trf  power  to  all 
kinds  of  mechanieal  apparatus  and 
other  machinery  requiring  ntotion 
aitd  force,  than  by  any  means  at 
preMut  practised  for  that  purpose.' 
The  action  of  this  preai  is  founded 
npon  the  fundamental  principle  in 
hydrostatics,  that  "  when  a  liquid 
mass  is  in  equilibrium,  under  the 
action  of  forces  of  any  kind,  every 


midecule  or  part  of  the  mass  sus- 
tains Ka  equal  pressure  in  all  direc- 
tions." From  this  it  follows,  that 
a  pressure  eierted  on  any  portioi 
of  the  surface  of  a.  confined  mass  ol 
fluid  ia  propagated  throughout  the 
mau,  and  trausfeired  undiminished 
to  the  entire  sur&ce  in  contact 
with  the  water.  The  Gist  sugges- 
tion of  the  hydraulic  press  is  con- 
sidered to  have  been  made  bj  Pas- 
cal in  the  middle  of  the  1 7th  cen- 
tury ;  but  Brameh  was  the  first  to 
carry  this  suggestion  into  practice, 
by  devising  and  applying  nppaxatns 
in  variODS  forms  for  the  purpose  of 
producing  pressure. 

Since  the  date  of  its  invention,' 
the  hydraulic  press  has  been  ex- 
tensively used  in  pressing  goods  of 
various  kinds.  Another  '" 
useful  applications  is  to 


HYD 


HTDBOSTATIC  PRESS. 


HYD 


of  giiden  and  bemi  of  CMt  irtn 
(See  article,  Bramali'$  AydrMlatic 
pr*»t.)  Its  latest  ind  perbapi  mort 
remarkable  dnty  is  thst  of  lifting 
tbe  iron- work  of  tubulai  bridgei  en 
matnfrom  tbe  wRter  level  to  theiT 
fiDsl  altitude. 

Hydrostatic  pieuet  consiit  e 
■entially  of  two  diatinct  paiti,  vi 
tbe  prtti,  or  machine  in  which  the 
fbrce  acquired  ii  applied,  and  tbe 
punning  qppomfiu,  b;  which  the 
water  Ui  forced  into  tbe  preas ;  these 
two  porta  of  tbe  entire  machine 
beii^  connected  only  by  the  pipe 


■how  the  main  ptrti  of  the  p 
viz.  the  cylindn",  into  which  the 
water  i»  t±aitted;  the  ram,  or  solid 
planner  or  piston;  i 
head  by  nhicb  the  preiaure  at  the 
end  of  the  ram  ii  distributed  over 
a  lengthened  lur&ce  for  ui 
flgures  show  the  cylinder  u  sup- 
ported in  a  frame  upon  giiden,  in 
a  manner  siioiUr  to  that  adopted 
in  laisiag  tbe  tnbe)  of  the  railway 
bridge  recently  erected  st  Conway. 
Fig.  3  sbowa  the  tectioa  of  a 
portable  fordng-pomp  as  commonly 
Died  for  proving  castings  with  the 
hydraulic  prets,  for  which  purpose 
the  press  is  applied  boriiontally, 
and  mounted  on  an  iron  carriage 
for  portability.  But,  however  va- 
ried  in  arrangement  for  particolar 
purposes,  tbe  pump  and  tbe  press 
consist  of  the  same  essential  parts, 
as  follows  :  the  pump  comprises  a 
dstem  or  kind  of  pail,  far  contsin- 
ing  the  water,  and  into  which  a 
barrel  descends  nearly  to  the  bot- 
tom. The  barrel  is  fitted  with  a 
plunger,  by  working  which,  the 
water  is  driven  through  a  small 
tube  or  pipe  into  tbe  press.  The 
pump  IS  fuimshed  with  s  safety. 


»  with  a 


V  for 


thim^  which   the  ^ 
' —  o  the  other.    Of  Uie  ac- 

g  flgnres,  Nos.  I  and  2 


letting  off  the  water  as  required. 
The  press  consists  of  a  strong  hol- 
low cylinder  of  cast  iron,  close  at 
one  end,  and  of  a  sobd  ram  work- 
ing through  tbe  other  end,  the 
water-pipe  being  inserted  through 
the  metal  of  the  cylinder  in  a  water- 
tight screwed  aperture.  Pig.  1  Li 
an  elevation  of  the  press ;  flg.  2,  a 
vertical  section  of  the  press,  taken 
at  ngbt  angles  to  the  elevation ; 
and  fig  3,  a  vertical  section  of  a 
pnmp  0  IS  the  cast-iron  cyhnder  j 
b,  the  ram ,  c,  tbe  casing  or  fnme 
of  the  cyhndn ,  d  d  are  two  cast- 
iron  girders  sapporting  the  casing ; 
e  IS  tbe  cast-iron  cross-head;//^ 
two  gmde-njds ,  j,  the  water-pipe 
from  the  pump,  inth  a  lever-valve 
at  h,  by  closing  which  the  pressure 
will  be  retained,  should  the  pipe 
burst.   On  fig.  3,j  shows  tbe  other 


HYDROSTATIC  PRBSS. 


HYD 


end  of  the  water-pipe,  which  ii  *t  t 
serened  into  a  ituffing-box  on  the 
pump ;  i  ig  the  lever  of  the  ufetj- 

vatve,  a',  wMeh  ii  cylindrical,  and 
finished  with  ■  conical  end,  which 
fits  a  Beating  of  similar  form ;  I  il 
a  standard  Ixilted  at  n  to  the  corer 


of  the  dit«ni,  and  hanng  an  eye 
bou  at  H,  fiir  gmdins  the  plnoser , 

op  a  a  link  pinned  to  the  plnDver; 
;  is  the  pail  or  ciitem  for  hol£ng 
the  water;  r,  the  barrel  paasing 
through  an  opening  in  the  corer, 
and  fixed  to  it  with  bolti  and  nuta ; 
tr,  the  lower  valre-seat,  and  conical 
three-aided  Talve,  the  former  being 
■crowed  into  the  end  of  ^e  barrel ; 


(,  a  tube  depending  bom  the  valve- 
aeat  a,  and  screwed  upon  it :  thia 
tube  leacbea  nearly  to  the  bottom 
of  the  ciitem,  and  is  perforated  at 
the  end  with  minute  apertures, 
through  which  the  water  ia  ad- 
mitted without  diit  or  porticlea, 
which  would  injure  the  working  of 
the  pump )  ■  ii  the  plunger,  which 
works  through  a  atuffing-box  on 
the  lop  of  the  barrel,  and  ia  made 
witli  i  alol  at  V,  to  recuTe  the  link 
op,  which  is  pinned  to.it  tud  also 
to  the  pnmp-handle;  w  ia  the 
pluuger-rod,  mewed  into  the  upper 
cud  of  the  plunger ;  y,  the  pnmp. 
haaiile.jointedto  the  standard  atf. 
During  the  fiiai  part  of  the  actioa 
of  the  pomp,  wUle  no  great  pre». 
e  is  yet  prodaced,  the  handle  ia 
~'~ined  to  the  outer  of 


a  larger  atroke  with  the 
{NstoQ,  and  thus  saTca 
tune :  the  pin  is  after- 
wards removed  to  the 
inner  bote    to  have  all  the  ad- 
>  int  age  of  the  leverage,    t  is  the 
upper  or  discharge  Taive,  with  a 
coiucal  end  -  it  is  introduced  from 
the  Tap,  and  covered  with  a  short 
Errew  which  likewiae  regulate*  the 
liit  of  the  valve.     This  valve  is 
ti-rniei  by  being  simply  filed  flat 
QUI  uf  the  round. 

The  rule  for  fiodiDg  the  increase 
i>f  power  commanded  by  the  pump 
IS  derived  — first,  from  the  ratio  o( 
tijc  areas  of  cross  section  of  plunger 
rit  iiump  and  ram  of  press;  and, 
setonillv  from  the  ratio  of  the  le- 
irrB).!.  of  the  pump-handle.  Thus 
supiirjse  theplungertobel  inch  and 
the  ram  6  mchei  in  diameter,  and 
the  arms  of  Ihe  lever  or  handle  as  I 
to  4,  the  power  will  be  thus  found: 


multiplied  by    . 


And  thus  a  power  equal  to  20Ibi., 
applied  on  the  end  of  the  pump- 
handle,  will  produce  a  preaaore 


HYD 


HYGROMETER. 


HYP 


equal  to  1 1,520  fts.  on  the  ram,  or 
5  tons  2  cwt.  3  qrs.  12  lbs. 

Each  of  the  presses  applied  at 
Conway  was  worked  by  a  steam 
engine  having  a  horiEontal  cylinder 
17  inches  in  diameter  and  16  inches 
stroke,  with   piston-rods  working 
through  stiiffing-boxes  at  both  ends 
of  the  cylinder.    The  piston-rods 
worked  two  fordng-pumps,  with 
plungers  1-^  inch  cUameter  and  16 
inches  stroke.    The  rams  of  these 
presses  were  each  5  feet  2  inches 
long  and  18f-  inches  in  diameter, 
with  a  space  nearly  {  inch  wide 
around.     The  cylinders  were  37^ 
inches  diameter  externally,  and  20 
inches  internally,  the  metal  being 
8}  inches  in  thickness:  the  orifice  of 
the  water-tubes  f  inch  in  diameter. 
Hydro9tatie  paradox.    This  may  be 
explained  upon  the  same  principles 
as  the  mechanical  powers ;  and  an 
explanation  conducted  in  this  man-^ 
ner  strips  it  of  its  paradoxical  ap- 
pearance. 
Hydrostatics,  the  science  which  treats 
of  the   mechanical  properties  of 
fluids;  strictly  speaking,  the  weight 
and   equilibrium   of  fluids.     The 
weight  and  equilibrium  of  fluids  at 
rest  ar&  the  objects  of  this  science. 
When  the  equilibrium  is  destroyed, 
motion   ensues;  and  the  science 
which  considers  the  hiws  of  fluids 
in  motion  is  hydraulics. 
Hydrometer :  this  instrument  is  used 
to  ascertain  the  quantity  of  mois- 
ture held  in  the  atmosphere.   There 
are  several  kinds  of  hygrometers 
in  use,  namely,  De  Luc's,  Saussure's, 
Leslie's,  and  Professor  Darnell's. 
The  latter  is  considered  preferable. 


ICE 

IcK-HOusK,  a  subterranean  chamber 
for  preserving  ice  free  from  mixing 
with  the  ordinary  changes  of  tem- 
perature 
leh  Dien,  in  heraldry,  *  I  serve ' 
Icknographyj  in  drawing.  The  ichno- 
graphy  of  a  building  represents  the 
plan  or  ground-work;  the  ortho- 


HypdBthraif  open  above:  in  temples 
of  this  description  the  cella  was 
in  part  exposed  to  the  air:  they 
had  a  double  range  of  columns 
within  the  cella,  £yiding  it  into 
three  alae,  or  aisles.  The  alae  on 
either  side  were  roofed,  but  that  in 
the  middle  had  no  covering. 

Hypatruntf  a  latticed  window  over 
the  entrance-door  of  a  temple 

Hyperbola,  a  section  of  a  cone  made 
by  a  plane,  so  that  the  axis  of  the 
section  inclines  to  the  opposing  leg 
of  the  cone,  which  in  the  parabola 
is  parallel  to  it,  and  in  the  ellipse 
intersects  it 

Hyperthyrum,  that  part  of  the  frame 
of  a  doorway  which  is  over  the 
supercilium 

Hyperthyrum,  in  Greek  architecture, 
a  frieze  and  cornice  supported  by 
friezes  and  consoles 

Hypoeastanum,  or  chestnut  broum,  is 
a  brown  lake  prepared  from  the 
horse-chestnut:  it  is  transparent 
and  rich  in  colour,  warmer  than 
brown  pink,  and  very  durable  both 
in  water  and; oil :  in  the  latter  it 
dries  moderalely  well 

Hypocausis,  among  the  Greeks,  a  fur- 
nace with  flues  running  underneath 
the  pavement  of  an  apartment,  to 
increase  the  temperature 

Hypoeaustum,  the  stove-room  of  a 
bath,  in  which  was  placed  the  prae- 
fumium  for  heating  the  caldaria 

Hypogaum,  in  ancient  architecture,  a 
name  common  to  all  the  under- 
ground parts  of  a  building 

HypoiracheUum,  that  part  of  the  ca- 
pital of  a  column  which  occurs  be- 
tween the  shaft  and  the  annulets 
of  the  echinus 


IMP 

graphy  the  front;  and  the  sceno- 

graphy  the  whole  building. 
leosahedron,  in  geometry,  a  regular 

body  or  solid,  consisting  of  twenty 

triangular  pyramids 
Image,  a  term  applied  to  a  statue 
Imbowment,  an  arch  or  vault 
Impages,  the  horizontal  parts  of  the 


227 


r 


IMP 


INDIAN  ARCHITECTURE. 


IND 


finme-work  of  dooiB,  oommonly 
tamed  railft 

Impale,  in  heraldry,  to  coigain  two 
coeti  or  arms,  as  a  wife's  with 
those  of  her  husband 

Iwipetutf  in  mechanics,  iriolent  ten- 
dencj  to  any  point,  Yiolent  effort, 
force,  momentmn,  motion 

/fl^'n^tf,  in  mechanics,  to  fall  against, 
to  strike  against,  to  dash  with 

Impkofiumf  the  dstem  in  the  central 
part  of  the  court  or  atrium  of  a 
Roman  house,  to  receiTe  the  rain- 
water 

In^Hfitt  the  horizontal  mouldings  or 
capitals  on  the  top  of  a  pilaster, 
pillar,  or  pier,  from  which  an  arch 
springs:  in  classical  architecture 
the  form  yaries  in  the  sereral  orders. 
Sometimes  the  entablature  of  the 
order  serves  for  the  impost  of  an 
arch. 

In^fOii/nrekivoU,  and  keystone.  The 
height  of  the  impost  should  be  from 
one-ninth  to  one-seventh  of  the 
width  €i  the  aperture,  and  the 
breadth  of  the  archivolt  not  more 
than  an  eighth  nor  less  than  a 
tenth  of  it  The  lireadth  of  the 
under  side  of  the  key-stone  should 
be  the  same  as  the  breadth  of  the 
archivolt,  and  its  sides,  of  course, 
concentric ;  its  length,  once  and  a 
half  its  breadth,  but  not  more  than 
double  its  breadth. 

In^tuliUfe  force  is  that  wliich  acts 
during  an  extremely  short  time, 
and  is  so  called  because  the  forces 
tiiat  take  place  in  any  impulse,  or 
impact,  are  speedily  exhausted 

Ineiee,  to  cut ;  to  engrave ;  to  carve 

IneUned  plane  (the),  in  mechanics,  is 
a  plane  which  makes  with  the  hori- 
sontal  plane  any  angle  whatever, 
forming  one  of  the  simplest  me- 
chanical powers.  The  inclination 
of  the  plane  is  measured  by  the 
angle  formed  by  two  lines  drawn 
from  the  sloping  and  the  horizontal 
plane,  perpendicular  to  their  com- 
mon intersection. 

increment i  an  increase ;  produce 

Inenutation,  If  water,  impregnated 
with 'calcareous    matter,  remains 

228 


long  in  contact  with  extraneous 
sulmtanoes,  an  earthy  incrustation 
takes  place  that  soon  encloses  the 
encrusted  substance,  which  is  then 
said  to  be  petrified. 
Indian  JtreMteetwre  consists  of  two 
distinct  styles, — the  Buddhist  and 
thcBrahminical, — the  former  being 
the  earliest,  and  consisting  of  topes 
or  tumuli,  large  domical  buildings 
of  brick  or  stone,  either  quite  solid 
or  containing  one  or  more  small 
chambers,  in  which  are  deposited 
relics,  coins,  and  other  similar  ob- 
jects, which  the  greater  number  of 
tiiem  were  erected  to  enshrine. 

The  principal  topes  are  now 
found  in  Ceylon  and  Afghanistan, 
but  they  also  exist  in  Burmah  and 
in  other  neighbouring  countries. 

The  next  class  of  Buddhist 
buildings  are  the  Chaitya  halls, 
similar  in  plan  and  use  to  the  early 
basilicae:  these  exist  principally  in 
caves  in  India.  And  lastly,  viharas 
or  monasteries,  in  which  the  monks 
attached  to  the  Chaitya  halls  re- 
sided :  these  also  exist  principally 
as  caves  in  India,  and  as  structural 
buildings  in  all  countries  where 
Buddhum  is  still  practised. 

Brahminical  or  Hindoo  architec- 
ture consists  mostly  of  temples,  pro- 
perly so  called.  These  in  almost 
every  instance  are  towers,  square  in 
plan,  or  nearly  so,  built  over  the  cell 
or  sanctum  of  the  temple.  In  the 
south  of  India,  the  upper  part  forms 
a  right-lined  pyramid;  in  the  north, 
the  outline  is  curvilinear,  sometimes 
tapering  to  a  spire. 

To  these  towers  are  attached 
porches  of  greater  or  less  dimen- 
sions. In  the  north  there  are 
generally  square  halls  without  pil- 
lars^in  the  south,  as  universally 
pillared— sometimes  attached,  at 
others  detached  from  the  temple 
itself:  in  the  latter  case,  in  the 
south,  some  of  the  porches  possess 
from  500  to  1000  pillars,  though 
this  is  never  the  case  in  the  north. 

These  temples  are  generally  aur- 
rounded  by  a  square  court :  in  the 


IND 


INERTIA. 


INN 


Bontb,  three,  four,  and  sometiines 
even  seven  such  enclosures  sur- 
round the  principal  cell,  the  outer 
one  being,  in  many  instances,  some 
miles  in  drcumference. 

These  Hindoo  temples  exist 
sometimes,  though  rarely,  as  rock- 
cut  temples ;  but  generally  they  are 
structural. 

Between  these  styles  comes  a 
third,  the  Jaina  style,  being  a  mix- 
ture of  the  two,  possessing  some  of 
the  characteristics  of  both,  and 
frequently  displaying  more  ele- 
gance than  the  first,  and  less  taw- 
driness  than  the  other.  By  the 
introduction  of  domes,  whose  use 
was  thus  brought  to  great  perfec- 
tion, an  element  was  added  which 
was  a  great  improvement  on  the 
other  two  styles,  and  from  which 
that  of  Jaina  originated. 

The  absence  of  the  arch  in  all 
constructions  of  every  age  is  gene- 
ral throughout  India,  as  the  prin- 
ciple was  quite  unknown.  The 
upper  parts  of  the  buildings  were 
supported  on  square  piers  or  pil- 
lars, and  frvm  all  sides  of  their 
capitals  brackets  projected  equal 
to  their  vndth,  and  leaving  gene- 
rally a  space  equal  to  three  diame- 
ters between  their  greatest  projec- 
tion, thus  leaving  only  one-ha£f  of 
the  whole  length  of  the  architrave 
unsupported;  but  when  a  greater 
space  was  required,  a  succession  of 
projecting  brackets,  placed  above 
each  other,  was  adopted,  sometimes 
meeting  in  the  centre,  and  thus 
having  the  effect  of  the  horizontal 
arch. 
Indian  Ink  :  the  pigment  well  known 
under  this  name  is  principally 
brought  from  China  in  oblong 
cakes,  of  a  musky  scent,  prepared 
for  painting  in  water,  &c. 
Indian  red,  a  colour,  is  brought  from 
Bengal,  and  is  a  very  rich  iron  ore, 
or  peroxide  of  iron.  It  is  an  ano- 
malous red,  of  a  purple-russet  hue, 
of  a  good  body,  and  valued,  when 
fine,  for  the  pureness  and  lakey 
tone  of  its  tints 


Indian  yellow  is  a  pigment  long  em- 
ployed  in  India  and  subsequently 
introduced  generally  into  painting 
in  European  countries.  It  is  im- 
ported in  the  form  of  balls,  is  of  a 
fetid  odour,  and  is  produced  from 
the  urine  of  the  cameL  It  has 
also  been  ascribed,  in  like  manner, 
to  the  buffalo,  or  Indian  cow,  after 
feeding  on  mangoes ;  but  the  latter 
statement  is  incorrect.  Indian  yel- 
low resists  the  sun's  rays  with  sin- 
gular power  in  water-painting. 

Indicator,  the  apparatus  for  showing 
the  force  of  the  steam,  and  the 
state  of  exhaustion  in  the  cylinder 
during  the  stroke 

Indigo,  or  Indian  blue,  is  a  pigment 
manufactured  in  the  East  and  West 
Indies  from  several  plants,  but  prin- 
cipally from  the  anil  or  indigofera 

Inertia,  the  passiveness  of  matter: 
matter  has  not  the  power  of  putting 
itself  into  motion^  neither  has  it  the 
power  of  stopping  itself  when  put 
into  motion  by  the  action  of  an  ex- 
ternal force,  as  it  requires  as  much 
force  to  stop  a  body  as  it  requires 
to  put  it  in  motion 

If^mmable  air,  hydrogen  gas 

IvfiiuB,  in  hydraulics,  the  act  of  flow- 
ing into  any  thing,  as  the  tide  into 
a  bay  or  river 

Injection-cock,  the  stop-cock  in  the 
ejection-pipe,  for  shutting  off  the 
supply  of  cold  water  used  for  the 
condensation  of  steam 

Injection-pyae,  the  pipe  through  which 
the  injection  water  passes  to  the 
condenser;  in  a  steam  vessel  the 
injection-pipe  is  open  to  the  sea,  at 
the  bottom  of  the  vessel 

Inn  or  Hostel,  anciently  a  lodging, 
house,  or  a  house  of  lodging  and 
refreshment  for  travellers :  houses 
for  lodging  the  collegians  at  Cam- 
bridge and  Oxford  were  so  called 

Inns  of  court,  houses  in  which  there 
are  many  lodgings  for  the  accom- 
modation  of  students  and  practi- 
tioners at  law 

Innate  force,  in  physics,  the  vis  inertia 

Inner-post,  in  ship-building,  a  piece 
brought  in  at  the  fore-side  of  the 


229 


INS 


INTERCOLUMNIATION. 


INT 


I 


main-post,  and  generally  oontiniied 
as  high  as  the  wing-transom,  to 
seat  the  other  transoms  upon 
huerium  optu,  according  to  Vitni- 
^ns,  a  mode  of  building  walls  used 
by  the  Bomans,  in  whidi  the  stones 
were  small  and  unhewn,  similar  to 
idiat  is  now  called  rubble-work 
Ifuulated  eohmma,  in  architectnre, 
are  those  which  are  unconnected 
with  any  wall  or  building 
IniaffHo,  in  sculpture,  &c,  any  thing 
that  has  figures  engraved  on  it,  so 
as  to  rise  above  the  ground 
Iniemte  bluet  indigo  refined  by  so- 
lution and  precipitation,  in  whidi 
state  it  is  equal  in  colour  to  Ant- 
werp blue.  By  this  process,  indigo 
also  becomes  durable,  and  much 
more  powerftd,  transparent,  and 
deep.  It  washes  and  works  weD  in 
water;  and  in  other  respects  it  has 
the  common  properties  of  indigo. 
Iniereohtmmiatum.  Thespaoehetween 
two  columns  is  called  an  interoo- 
Inmniation.  When  columns  are  at- 
tached to  the  wall,  this  space  is  not 
under  sudi  rigorous  laws  as  when 
they  are  quite  insulated ;  for,  in  the 
latter  case,  real  as  well  as  i^iparent 
•olidity  requires  them  to  be  near 
eadi  other,  that  they  may  better 
sustain  the  entablatures  whidi  it 
is  their  office  to  carry. 

DiFFKBKNT  SORTS. — Thc  dif- 
ferent interoolnmniations  had  the 
following  names  bestowed  on  them 
by  the  Greeks,  and  they  still  retain 
their  ancient  aj^Kllations : 
PycnoatyloB,  when  the  columns  are 
once  and  a  half  of 
their  diameter  dis- 
tant fromeachothcr. 
Syatylos  ••  when   their   distance 
firom  eadi  other  is 
two  diameten. 
Busty los  ..  when  their  distance 
fimn  eadi  other  is 
two  diametos  and  a 
quarter. 
Diastylos..  when  their  distance 
from  eadi  oliier  is 
tiiree  diameters  and 
a  quarter. 

2io 


Arnostyloa. .  when  their  distance 
tram  each  other  is 
four  diameters. 

In  the  Doric,  however,  tiie  in- 
terodlumnSation  is  regulated  by  the 
disposition  of  the  triglyphs  in  the 
fnuei  for  the  triglyph  ought  al- 
ways to  be  placed  over  the  centre 
of  a  column,  and  the  metope  should 
be  square.  In  the  Tuscan  inter- 
¥al,  the  architrayes  being  of  wood, 
the  space  may  be  consitombly  ex- 
tended. 

A  strict  adherence  to  the  above- 
named  intervals  between  the  co- 
lumns produces  some  irregularity 
in  the  arrangement  of  the  modil- 
lions  and  dentils  of  the  Corinthian, 
Ionic,  and  Composite  eomices, 
whidk,  though  not  offiensiTe,  is 
better  avoided.  Vignola  therefore 
has,  with  some  propriety,  made  his 
eustykw  interortnmniation  equal  to 
two  diameters  and  one-third  in  all 
but  the  Doric  order. 
ImiereohammaiiemB.  Cohmins  maybe 
said  to  be  either  engaged  or  insu- 
lated: when  insulated,  they  are 
cither  plaoed  very  near  the  walls 
or  at  some  conaiderahle  distance 
from  tiiem. 

With  regard  to  engaged  columns, 
or  sndi  as  are  near  ^  waDs  of  a 
buflding,  the  intcrrohimniations  are 
not  limited,  but  depend  on  the  width 
of  the  arches,  windows,  nidies,  or 
other  objects,  and  their  decoratimis, 
placed  within  them.  But  columns 
that  are  entirely  detadied,  and  per- 
fana  alone  the  office  of  supporting 
flie  entaMatare,  as  in  peristyles, 
porches,  andgaDaies,  must  be  near 
each  other,  both  lor  the  sake  of 
real  and  apparent  solidity. 

The  ancieBts  had  several  manners 
<tf  spacing  their  columns,  whidi  are 
deaoibed  by  Yitravins  in  his  third 
and  fourth  books.  Those  practised 
in  the  Ionic  and  Corintiiiui  orders 
were,  the  pycnostsie,  the  systyle, 
the  eostyle,  the  diaatyle,  and  the 


IntheDoric  order  fliey  used  other 
umniatioDS,  regidstiBg  tiiem 


INT 


IONIC  ORDER. 


ION 


■ 


by  the  triglyphs,  of  which  one  was 
always  to  be  placed  directly  over 
the  middle  of  each  oolimui,  so  that 
they  were  either  systyle  monotri- 
glyph,  of  one  diameter  and  a  half; 
diaatyle,  or  aneostyle:  the  Tuscan 
intervals  were  exceedingly  wide, 
some  of  them  being  above  seven 
diameters,  which,  as  the  architraves 
were  of  wood,  was  practicable. 

Vitruvias  intended  the  five  inter- 
columniations,  mentioned  in  his  3rd 
book,  merely  ifor  the  Ionic  and  Co- 
rinthian orders ;  the  latter  of  which, 
according  to  him,  differed  from  the 
former  only  in  its  capital ;  for,  in  the 
second  and  seventh  chapters  of  his 
fomrth  book,  he  establishes  other 
intervals  for  the  Doric  and  Tuscan 
orders.  Nevertheless,  they  have  em- 
ployed these  intercolumniations  in 
different  orders.  Palladio  has  used 
the  systyle  in  the  Corinthian,  and 
the  aneostyle  in  the  Tuscan;  by 
which  means  the  Corinthian  peri- 
style, of  which  the  character  should 
be  extreme  delicacy  and  lightness, 
becomes  twice  as  strong  and  mate- 
rial as  the  Tuscan,  of  which  the 
distinguishing  characteristics  ought 
to  be  extreme  soUdity. 

IiUerUgnium,  in  ancient  architecture, 
the  space  between  the  ends  of  the 
tie-beams 

InterpensiviBi  timbers  in  the  roof  of 
the  cavsedium,  extending  in  a  dia- 
gonal direction  from  the  angles 
made  by  the  walls  of  the  court  to 
the  angles  made  by  the  junction  of 
the  beuns  supporting  the  roof 

IfUradott  the  soiSit  or  under-surface  of 
an  arch,  as  opposed  to  extradoa 

In  vaeuOf  a  void  or  empty  space 

Inventionf  in  painting,  consists  princi- 
pally in  three  things:  first,  the 
choice  of  a  subject  properly  within 
the  scope  of  art ;  secondly,  the  sei- 
zure of  the  most  striking  and  ener- 
greric  moment  of  time  for  represen- 
tation ;  and  lastly,  the  discovery 
and  solution  of  such  objects,  and 
such  probable  incidental  circum- 
stances,  as,  combined  together,  may 
best  tend  to  develop  the  story,  or 


augment  the  interest  of  the  piece. 
The  cartoons  of  Raphael  fiurnish 
an  example  of  genius  and  sagacity 
in  this  part  of  the  art. 

Iiwerse,  turned  back  or  inverted ;  op- 
posed to  direct 

Jtwerse  ratiOf  when  more  requires 
less,  or  less  requires  more 

Ifwerted  arch,  an  arch  of  stone  or 
brick,  with  the  crown  downwards, 
commonly  used  in  the  construction 
of  tunnels 

Iodine  scarlet  is  a  new  pigment,  of  a 
peculiarly  vivid  and  beautiful  colour, 
exceeding  even  the  brilUancy  of 
Vermillion.  It  has  received  several 
fslse  appellations,  but  is  truly  an 
iodide  or  biniodide  of  mercury,  vary- 
ing in  degrees  of  intense  redness. 
It  has  the  body  and  opacity  of  Ver- 
million, but  should  be  used  with  an 
ivory  palette-knife,  as  iron  and 
most  metals  change  it  to  colours 
varying  from  yellow  to  black. 

Iodine  yeUow^  ioduret  of  lead,  is  a 
precipitate  from  an  add  solution  of 
lead  by  an  alkaline  solution  of 
iodine,  of  a  bright  yellow  colour, 
which,  from  its  active  chemical  affi- 
nities, and  the  httle  experience  of 
its  qualities  in  painting,  is  to  be 
employed  with  doubt  and  caution 

Ionic  capital.  The  Greek  architects 
must  have  possessed  much  science 
in  the  formation  of  curves  of  every 
description.  We  cannot  generate 
the  curve  of  the  volute  of  an  Ionic 
capital  but  by  approximation ;  but 
the  inventors  of  the  order  must 
have  known  how  to  generate  this 
and  other  curves  in  Greek  architec- 
ture, on  fixed  principles ;  so  must 
the  artist  in  vases,  &c.  Mr.  Jopling 
is  said  to  have  discovered  the  true 
generic  curve. 

Ionic  Order:  this,  says  Palladio,  **  had 
its  origin  in  Ionia,  a  province  of  Asia; 
and  we  read  that  the  famous  tem- 
ple of  Diana  at  Ephesus  was  built 
of  that  order.  The  column,  with 
its  capital  and  base,  is  nine  modules 
high;  and  by  a  module  is  under- 
stood the  diameter  of  a  column  be- 
low.     The  architrave,  frieze,  or 


231 


IRQ 


cornice,  haTe  the  fifth  part  of  the 
height  of  the  column.  When  the 
columns  are  single,  the  inter-co- 
lumns are  of  two  diameters  and  a 
fourth  part,  and  this  is  the  most 
beautiful  and  commodious  manner 
of  all  inter-columns,  which  Vitru- 
vius  calls  eustylos." 

Amongst  the  ancients,  the  form 
of  the  Ionic  profile  appears  to 
have  been  more  positively  deter- 
mined  than  that  of  any  other  order ; 
for  in  all  the  antiques  at  Rome,  the 
temple  of  Conconl  excepted,  it  is 
exactly  the  same,  and  conformable 
to  the  description  which  Vitruvius 
has  given  of  it. 

Modem  artists  have  likewise  been 
more  unanimous  in  their  opinions 
upon  the  subject ;  all  of  them,  ex- 
cepting Palladio  and  his  imitators, 
having  employed  the  dentil  cornice, 
and  the  other  parts  of  the  profile, 
nearly  as  they  are  found  in  the  Co- 
liseum, the  temple  of  Fortune,  and 
the  theatre  of  Marcellus. 

In  Palladio's  works  we  meet  with 
three  different  Ionic  entablatures ; 
all  of  them  very  beautifuL  The 
first  is  the  true  antique,  which 
he  has  made  use  of  at  the  palace  of 
the  Porti ;  and  in  several  doors  and 
windows  of  the  Thiene  and  Val- 
marana  palaces,  in  Vicenza.  The 
second  is  a  very  judicious  imitation 
of  the  entablature  in  the  temple  of 
Concord,  and  is  executed  by  him 
in  the  upper  arcade  of  the  basilica 
in  the  same  city.  The  third,  which 
is  an  invention  of  his  own,  being 
the  same  vnth  that  in  his  book,  he 
has  employed  with  some  small  dif- 
ference at  the  Chiericato  palace,  at 
the  rotunda  of  Marchese  Capra, 
and  in  various  others  of  his  build- 
ings in  the  Vicentine,  or  at  Venice. 
Iron,  the  most  useful  and  the  most 
abundant  of  the  metals,  is  found  in 
various  conditions  of  ore  in  most 
parts  of  the  earth.  Those  ores 
which  are  prindpaUy  worked  for  the 
production  of  the  metal  for  manu- 
fEicturing  purposes,  are  either  oxides 
or  carbonates,  that  is,  they  contain 

232  " 


IRON.  IRQ 

the  metal  in  a  state  of  combination 
either  with  oxygen,  or  with  oxygen 
and  carbonic  acid.  The  oxides  are 
the  best  ores,  and  are  found  in  vast 
beds  in  Sweden :  the  carbonates  are 
inferior  in  point  of  strength  and 
ductility,  and  therefore  require  an 
extensive  reduction.  They  form  the 
greater  portion  of  the  iron  ores  of 
Britain. 

The  principal  varieties  of  the  ox- 
ides of  iron  are, — ^the  magnetic;  the 
massive,  found  in  the  north  of  Eu- 
rope, and  other  parts  of  the  world ; 
the  micaceous,  found  in  the  lava  of 
volcanoes,  &c. ;  and  the  red  and 
brown  haematites,  found  in  Great 
Britain  and  Europe.  The  princi- 
pal varieties  of  the  carbonates  are, 
the  massive,  found  in  Great  Britain 
and  Ireland,  Europe,  and  America; 
and  also  the  argillaceous,  conunonly 
known  as  day  iron-stone,  found 
abundantly  in  beds  and  coal  deposits 
in  England,  Wales,  and  Scotland. 

Besides  theoxides  and  carbonates 
here  enumerated,  iron  is  found  in 
large  quantities  in  combination  with 
sulphur;  and  the  several  compounds 
thus  formed  are  knovm  as  pyrites, 
several  varieties  of  which  are  found 
inNorway,  Sweden,  Germany,  Ame- 
rica, and  in  many  parts  of  England. 

Various  artificial  oxides  of  this 
metal  are  applied  to  medicine,  dye- 
ing, and  other  purposes  in  the  arts. 

The  tenacity  and  strength  of  iron 
are  impaired  by  its  adulteration 
vrith  foreign  matters.  Thus,  of  the 
oxides  and  carbonates,  those  are 
best  in  which  the  proportion  of  the 
metal  is  great.  These  qualities  are 
further  increased  by  fusion,  and  by 
the  mechanical  process  of  hammer- 
ing; and  this  fact  points  to  the  main 
distinction  in  the  kinds  of  iron  as 
applied  for  manufacturing  purposes, 
vis.  foundry  iron,  and  forge  iron. 

In  the  manufacture  of  iron,  the 
first  process  is  the  reduction  of  the 
iron-stone  or  ore,  technically  called 
the  mine,  into  the  state  of  a  metaL 
This  is  done  by  fusion  in  a  furnace, 
with  coke  added  to  produce  com- 


IRO 


IRON. 


IRO 


bastion,  and  limestone  to  act  as  a 
flux  and  assist  tlie  fosioii  of  the  ore. 
An  artificial  current  of  air  is  neces- 
sary to  fuse  the  ore  in  these  furnaces, 
which  are  therefore  called  blast  fur- 
naces, and  prodded  with  tubes  or 
tuyeres,  through  the  tapered  noz- 
zles of  which,  strong  ciurentsof  air 
are  delivered  to  the  interior  of  the 
furnace,  the  required  yelodty  of  the 
blasts  being  sustsined  by  steam  or 
other  power.     Formerly  the  air  was 
thus  introduced  at  the  same  tempe- 
rature as  that  of  the  external  atmo- 
sphere; but  a  plan  has  for  many 
years  been  extensively  adopted  of 
previously  heating  the  air  for  the 
blasts  in  separate  vessels  to  a  high 
temperature,  by  which  the  fusion 
of  the  ore  is  so  powerfully  assisted, 
that  the  saving  (tf  fiiel  in  the  furnace 
is  many  times  greater  than  the 
quantity  used  for  the  preparatory 
heating  of  the  air.    Furnaces  thus 
supplied  are  termed  hot-blast  fur- 
naces, and  the  product  is  called  hot- 
blast  iron,  while  that  made  with  un- 
heated  air  is  called  cold-blast  iron. 
The  cost  of  the  process  of  reduc- 
tion with  the  hot  blast  being  so 
much  less  than  of  that  with  the 
cold  blast,  the  ultimate  value  of  the 
former  is  of  coarse  also  partly  de- 
pendent upon  the  quahty  of  the 
produce.   On  this  head  much  differ- 
ence of  opinion  has  often  been  mani- 
fested, and  with  all  the  earnestness 
usually  displayed  in  the  advocacy 
of  self-interest.    The  value  of  each 
process  must,  no  doubt,  arise  from 
the  completeness  of  the  fusion  pro- 
duced, and  the  separation  effected 
between  the  iron  and  the  impuri- 
ties combined  with  it  in  the  ore. 
The  hot-blast  furnace  effects  the 
fusion  more  readily  than  the  cold- 
blast,  but  admits  a  larger  combina- 
tion of  cinders  with  the  ore ;  and 
the    advantage    which    has   been 
taken  of  this  facility  of  adulteration, 
in  order  to  reduce  the  cost  of  pro- 
duction, has  doubtless  led  to  the 
introduction  into  the  market   of 
many  qualities  of  hot -blast  iron 

233 


which  are  inferior  in  strength  to 
that  made  with  the  cold  blast.  The 
results  of  some  of  the  most  care- 
fully conducted  experiments  which 
have  been  made  upon  the  strength 
of  cast  iron,  and  published  in  the 
6th  volume  of  the  new  series  of 
'Memoirs  of  the  literary  and  Phi- 
losophical Society  of  Manchester,' 
show  that  the  transverse  strength 
of  the  cold-blast  iron  tried  was 
about  2^  per  cent,  greater  than 
that  of  the  hot-blast.  The  experi- 
ments here  referred  to  were  made 
upon  rectangular  bars  1  inch  square, 
and  4  feet  6  inches  long  between 
the  supports.  The  mean  average 
breaking  weights,  placed  at  the 
middle  of  these  bars,  were — 

In  21  samples  of  hot- 
blast  iron   ....    445*5714 

In  22  samples  of  cold- 
bhtttiron  ....    4569090 

The  metal  is  allowed  to  flow 
from  the  furnace  into  rude  channels 
formed  on  the  surface  of  the  ground, 
where  it  cools,  and  is  taken  up  in 
the  form  of  rough  bars  about  3  feet 
long,  and  each  weighing  nearly  one 
cwt.,  which  are  technically  called 
pigs.  In  the  making  of  one  ton  of 
pig  iron  in  Staffordshire,  the  fol- 
lowing materials  are  used : 

Coal,  2  tons  5  cwt. 

If  coke  is  used  instead  of  coal, 
1  ton  17  cwt. 

Charred  mine,  or  ore,  2  tons 
5  cwt.  to  2  tons  10  cwt. 

Limestone,  13  cwt.  to  16  cwt. 

In  the  condition  of  pig  iron,  the 
metal  forms  the  two  staple  de- 
scriptions of  foundry  iron  and  of 
forge  iron,  according  to  its  quali- 
ties, and  the  proportiou  of  carbon 
and  oxygen  wMch  it  contains.  The 
several  sorts  of  pig  iron  are  consi- 
dered to  be  six  in  number,  and  are 
thus  distinguished :  Nos.  1,  2,  and 
3,  foundry  iron,  of  which  the  first 
two  are  never  used  for  forge  iron. 
No.  3,  or  dark  grey,  and  also  the 
fourth  quality  known  as  bright  iron, 
are  sometimes  used  for  the  foundry. 


IKO 


and  sometimes  for  the  forge.  The 
fifth  and  sixth  sorts,  known  as 
mottled  inm  and  whfte  iron,  are 
never  nsed  for  the  foondiy.  The 
order  here  ohserred  oonesponds 
with  that  of  the  pn^mrtion  of  car- 
bon and  oxygen  mixed  with  each 
kind  of  the  iron,  and  also  with  that 
of  the  floidity  to  whidi  the  metal  is 
ledncible :  it  also  corresponds  with 
the  scale  of  their  softness  and 
toughness.  Thus,  No.  1  has  tiie 
most  carbon  and  oxygen,  and  the 
white  iron  has  the  least.  No.  1  is 
the  most  floid  when  melted,  and  the 
white  iron  the  least  so.  Again,  No. 
1  is  the  softest,  and  the  white  iron 
the  hardest ;  and  No  1  is  the  tough- 
est, while  the  white  iron  is  the 
most  brittle.  But  white  iron  is  the 
best  adapted  for  conversion  into 
malleable  iron,  while  Nos.  1  and  2, 
foundry  iron,  contain  so  large  a  pro- 
portion of  carbon  and  oxygen,  that 
they  are  totally  unfit  to  be  manu- 
factured into  ban. 

The  conversion  of  pig  iron  into 
malleable  iron  is  effected  by  ex- 
tended processes,  or  subsequent  to 
those  by  which  the  ore  has  been? 
reduced  to  the  form  of  pig.    These 
processes  are  as  follow : 
1.  Refining, — 2.  Puddling,    ham- 
mering, and  rolling,— 3.  Cutting 
up,  piling,  and  rolling ;  the  3rd 
series   of  operations  being  re- 
peated. 

The  refining  is  for  the  purpose 
of  separating  a  portion  of  the  car- 
bon from  the  pig,  and  is  performed 
in  furnaces  fitted  with  tuy^s  for 
supplying  a  blast  of  air  to  the 
point  of  fusion.  The  metal  run 
from  the  refining  moulds  is  exceed- 
ingly brittle,  and  is  then  broken  up 
into  small  pieces,  and  committed 
to  the  puddling  or  reverberatory 
furnace,  to  undergo  a  further  puri- 
fication  from  the  oxygen  and  car- 
bon which  remain  after  the  process 
of  refining  is  accomplished.  While 
in  this  furnace,  the  mass  into  which 
the  pieces  of  refined  metal  become 
clustered  is  worked   and   stirred 

234 


IRON.  IRO 

about  by  the  workman  or  pnddler, 
nntil  its  thickness  and  tenacity  are 
so  for  increased  that  it  may  be 
formed  into  lumps,  or  balls,  which 
the  pnddler  does  with  tools  adapt- 
ed to  the  purpose. 

The  hammering  or  shingling  is 
performed  upoa  ti&e  baDs  or  blooms 
of  puddled  iron,  with  a  very  heavy 
hammer,  worked  by  a  cam-wheel, 
and  has  the  effect  of  improving  the 
soHdity  of  the  metal,  and  redudng 
the  bails  into  an  oblong  form,  by 
which  they  are  better  prepared  finr 
the  action  of  the  rollers. 

The  rolls  or  rollers  are  fitted  to- 
gether in  pairs,  and  so  formed  in 
the  periphery  and  arranged  in  size, 
that  open  spaces  are  formed  be- 
tween them,  through  which  the 
metal  is  passed  while  hot ;  and  each 
succeeding  pair  of  roUers  present- 
ing a  sma^Uer  space,  the  iron  which 
is  drawn  through  them  becomes 
proportionately  reduced  in  size  and 
increased  in  length. 

The  metal  has  thus  been  convert- 
ed from  a  hard  brittle  and  readily 
fusible  substance  into  a  malleable 
bar,  which  is  soft,  tough,  and  very 
difficult  of  fosion ;  but  it  is  still  fiu* 
from  fit  for  the  smith's  use,  being 
to  a  great  extent  unsound  in  struc- 
ture, imperfect  in  tenacity,  and 
irregular  on  the  surface. 

The  third  set  of  processes  is 
now  commenced  by  cutting  up  the 
puddled  bars  into  lengths  with 
powerful  shears.  These  lengths,  of 
various  dimensions,  according  to 
the  sized  bars  to  be  produced,  are 
carefoUy  piled  up  and  heated  in 
another  furnace  similar  to  the  pud- 
dling furnace,  and  which  is  called 
the  balling  furnace.  In  this  the 
bars  are  simply  heated  to  a  degree 
which  admits  of  their  becoming 
welded  together  in  the  pile  and 
adapted  for  reduction  to  the  form 
of  finished  bars  in  the  rolls. 

The  rolling  is  the  last  operation 
in  the  making  of  bar-iron.  The 
metal  is  drawn  successively  through 
a  series  of  rollers,  that  is,  between 


IRO 


IRON. 


IRO 


the  peripheries  of  each  pair  of 
rollers,  and  thus  gradually  reduced 
in  size,  increased  in  length,  and 
freed  fkt>m  the  cinder  and  other 
impurities  which  remain  after  the 
puddle-roUing  has  been  performed. 

The  last  set  of  operations  is 
sometimes  repealed  in  producing 
iron  for  superior  purposes.  The 
processes  here  described  will  giye 
a  general  idea  of  the  manufacture 
of  iron  from  the  natiye  ore  into  the 
form  of  malleable  bars;  and  it  may 
be  readily  conceiyed  how  an  exten- 
sion and  variation  of  the  process  of 
rolling  may  be  made  to  produce  the 
several  other  forms  in  which  this 
metal  is  prepared  for  the  construc- 
tions of  the  engineer,  the  smith, 
and  the  machinist. 

As  varieties  of  bar-iron  may  be 
mentioned, — L,  or  angle-iron ;  T, 
or  tee-iron ;  and  H,  or  deck-beam 
iron;  which  are  prepared  in  several 
sizes,  for  the  construction  of  roofs, 
iron  vessels,  &c.  The  malleable 
rails  used  for  railways  are  also 
produced  by  an  arrangement  of 
rollers. 

Boiler-plate  iron,  sheet -iron, 
hoop-iron  and  nail  rod-iron,  are 
produced  from  the  form  of  bars  by 
the  processes  of  heating  and  rolling, 
or  hanamering,  as  required.  Boiler- 
plates require,  accoi'ding  to  the 
desired  strength  and  size,  several 
repetitions  of  heating,  hammering, 
and  rolling.  Sheet-iron  is  distin- 
guished from  boiler-plate  by  being 
thinner ;  hoop-iron  is  rolled  in  the 
same  manner  as  the  bars,  but  be- 
tween rollers  without  grooves  in 
their  edges,  the  requisite  thickness 
being  effected  by  successive  pass- 
ages through  the  rollers,  which  are 
brought  nearer  to  each  other  at 
each  process,  by  means  of  adjust- 
ing screws.  Nail  rod-iron  is  rolled 
in  thin  bars,  which  are,  while  still 
hot,  passed  between  steel-cutters 
that  slit  them  up  into  the  form  of 
small  rods,  which,  although  rough, 
are  well  fitted  to  be  manufeu^ured 
into  nails. 


A  very  useful  form  of  sheet-iron, 
which  should  be  noticed,  is  that  d 
corrugated  iron,  which  is  produced 
by  passing  the  sheets  between 
rollers  having  grooved  peripheries. 
By  this  form,  the  strength  or  stiff- 
ness of  the  sheet  is  so  much  in- 
creased, that  sheet-iron  thus  formed 
may  be  usefidly  applied  to  a  great 
variety  of  purposes,  for  which  it  is 
otherwise,  owing  to  its  thinness 
and  pliability,  utterly  inadequate. 

By  the  combustion  of  charcoal 
with  the  coke,  and  the  adaptation 
of  a  peculiar  furnace  in  the  process 
of  smelting,  Mr.  Clay  has  succeeded 
in  producing  malleable  iron  direct 
from  the  ore,  and  thus  materially 
reducing  the  series  of  processes 
here  described.  The  results  thus 
brought  out 'are  of  a  very  interest- 
ing character,  and  promise  to  ac- 
quire a  great  practical  value. 

Iron.  Moses  forbade  the  Hebrews  the 
use  of  any  stones  to  form  the  altar 
of  the  Lord,  which  had  been  in  any 
manner  wrought  with  iron ;  as  if 
iron  communicated  pollution.  He 
says,  the  stones  of  Palestine  are  of 
iron,  that  is,  of  hardness  equal  to 
iron,  or,  being  smelted,  they  yielded 
iron.  "  An  iron  yoke  **  is  a  hard 
and  insupportable  dominion.  ''Iron 
sharpeneth  iron,"  says  the  Wise 
Man;  *'so  a  man  sharpeneth  the 
countenance  of  his  friend  -"  the  pre- 
sence of  a  friend  gives  us  more 
confidence  and  assurance.  God 
threatens  his  ungrateful  and  perfi- 
dious people  with  making  the 
heavens  irotif  and  the  earth  brass ; 
that  is,  to  make  the  earth  barren, 
and  the  air  to  produce  no  rain. 
Chariots  of  iron  are  chariots  armed 
with  iron,  with  spikes  and  scythes. 

Iron-^tanet  iron-bound  stone,  in  colour 
of  a  blueish  gray,  and  very  hard  to 
work:  it  contains  but  very  little 
iron 

Ironstone  has  the  appearance  of 
rusty  black  shale,  and,  when  laid 
together  in  large  heaps,  is  so  com- 
bustible that  it  ignites,  leaving  a 
a  calx  of  60  per  cent,  of  iron.    It 


235 


IRQ 


ITALIAN  ABCHITBCTUBS. 


ITA 


aboondt  in  Scothnd.  Common 
iron-stone  is  also  very  abondint 
in  oonneeCion  with  eoalt  and  in 
former  times  formed  the  principel 
supply,  which  indnoed  the  fonndn- 
tion  of  the  Canon  Iran  Woiis. 

Iron  wood  is  imported  from  the  Bra- 
zils, the  East  and  West  Indies,  and 
other  countries,  in  square  and 
round  logs,  6  to  9  inches  and  up- 
wards through.  Its  colours  are 
▼ery  dark  browns  and  reds :  some- 
times it  is  streaked,  and  generally 
strsii^t-grained:  used  prindpaDy 
for  ramrods,  turnery,  &c.,  and  is 
extremely  hard. 

Iron  yeOow,  jaune  de  for,  or  janne  de 
Mars,  &c.,  is  a  bright  iron  ochre, 
prepared  artificially,  of  the  nature 
of  sienna  earth.  The  colours  of 
iron  exist  in  endleM  ysriety  in  na- 
ture, and  are  capable  of  the  same 
Ysriation  by  art,  from  sienna  yel- 
low, through  orange  and  red,  to 
purple,  brown,  and  black,  among 
which  are  useful  and  valuable  dis- 
tinctions, which  are  brighter  and 
purer  than  native  ochres. 

lioekromam,  in  mechanics,  the  per- 
forming of  several  things  in  equal 
times;  such  as  the  vibrations  of 
the  pendulum 

Itodomont  a  building  every  way 
straight 

Uodomost  in  Greek  architecture,  ma- 
sonry cut  and  squared  to  the  same 
height,  so  that,  when  laid,  the 
courses  were  all  regular  and  equal 

Itomeirical,  projections  and  drawings 
so  termed 

Iscperimetriealf  in  geometry,  such 
figures  as  have  equal  perimeters  or 
circumferences 

Itoseelet,  in  geometry,  a  triangle  that 
has  only  two  sides  equal 

Isothermal^  in  chemistiy,  equal  heat 

Italian  Architeeturet^  style  nowmuch 
appreciated  not  only  in  Italy,  but 
in  England  and  France,  was  first  in- 
troduced at  the  reviviQ  of  classical 
architecture,  and  was  subsequently 
much  improved  and  adapted  to 
modem  refinement.  The  architec- 
ture of  Venice,  Florence,  Genoa, 


Home,  and  Sidly,  afford  to  the 
arehiteet  a  oomidete  library  of  ex- 
amples, by  the  possession  of  the 
several  woiks  published  of  the  ar- 
chitectnn  oi  the  palaces  and  man- 
sions oi  these  cities. 
HaiianJrekiteehire,Bowuau  Bespect- 
ing  buildings  originally  erected  in 
ItalyMr.Jos.Gwilthasthua  written: 
llie  Romans  followed  the  Greeks 
in  the  general  form  <tf  their  temples, 
hut  added  to  their  splendour  by  a 
greater  richness  of  detail,  and  the 
employment  of  other  orders.  For 
the  simple  steps  on  which  the  Greek 
temple  was  elevated,  they  substitu- 
ted pedestals,  and  added  a  base  to 
the  Doric  order.  The  climate  pre- 
scribed a  moro  elevated  pediment ; 
but  the  luxury  of  the  people  was 
the  cause  of  the  preference  given  to 
the  richer  orders  of  architecture. 

TBlCPI.n8,  BRinOBS,   AaUBDUCTS, 
COLUMNS,    THBATBBS,   &C. 

The  chief  temples  of  Rome  vrere 
^the  Capitol,  built  on  the  Tar- 
peian  or  Capitoline  mount,  by  Tar- 
quinius  Superbus.  (See  Qgrito- 
Uum,)  No  traces  of  it  at  present 
remain.  The  edifice  of  the  Capitol 
was  about  200  feet  square,  and  con- 
tained three  temples,  consecrated 
to  Jupiter,  Minerva,  and  Juno.  On 
the  Capitol  were  also  the  temples 
of  Terminus  and  Jupiter  Feretrius, 
and  the  cottege  of  Romulus. 

The  Pantheon,  built  by  Agrippa, 
the  son-in-law  of  Augustus,  and 
dedicated  to  Mars  and  Venus,  or 
more  probably,  frt>m  its  name,  to 
all  the  gods.  Pope  Boniface  IV. 
consecrated  it  in  honour  of  the  Vir- 
gin Mary  and  All  Saints,  a.d.  607. 
It  is  now  generally  known  by  the 
name  of  the  '  Rotonda;' — ita  dia- 
meter between  the  axes  of  the 
columns  is  147  feet :  like  most  of 
the  ancient  bidldings,  it  has  fallen 
a  prey  to  the  spoiler.  The  Balda- 
eUno  in  St.  Peter's  is  indebted  for 
its  materials  to  the  Pantheon  of 
Agrippa. 

The  temple  of  Apollo,  on  the 
Palatine  hill,  was  built  by  Angus- 


ITA 


ITALIAN  BUILDINGS. 


ITA 


tos :  a  temple  of  Diana  stood  on 
the  Ayentine. 

The  temple  of  Janns  was  sup- 
posed to  have  been  built  by  Romu- 
lus ;  that  of  Romulus  by  Papirius. 
Of  those  to  the  Sun  and  Moon, 
Fortuna  Virilis,  Vesta,  Minerva 
Medica,  Neptmie,  Antoninus  and 
P^uistina,  Concord,  Jupiter  Stator, 
and  most  particularly  of  the  tem- 
ple of  Peace,  considerable  remains 
are  fortunately  still  in  being.  The 
three  magnificent  arches  now  stand- 
ing of  that  last  named,  though  of 
themselves  majestic,  convey  but  a 
faint  idea  of  its  pristine  splendour. 
Of  the  temple  of  Jupiter  Stator, 
whose  colmnns,  capitals,  and  en- 
tablatures were  a  perfect  example 
of  the  Corinthian  order,  only  three 
columns  are  in  ^dstence.  The  re- 
mains of  the  temples  of  Antoninus 
Pius,  Claudius,  Hercules,  Jupiter 
Tonans,  Isis,  Romulus,  and  Venus 
and  Cupid,  are  still  interesting. 

No  vestiges  exist  of  the  temples 
dedicated  to  Satiun,  Juno,  Mars 
bis  Ultor,  in  the  forum  of  Augus- 
tus, nor  of  numberless  others  that 
adorned  the  city. 

The  temples  of  Balbec  and  Pal- 
myra are  the  last  of  the  ancient 
Roman  works  that  can  lay  claim  to 
the  appellation  of  classic  architec- 
ture. In  these,  invention  seems  to 
have  found  its  limits.  The  repro- 
duction and  new  adaptation  of  their 
detail  was  all  that  has  been  done 
by  following  artists. 

The  Romans,  not  content  with 
the  quadrilateral  temple,  made  use 
of  the  circular  form,  as  in  the  Pan- 
theon, temple  of  Vesta,  and  others 
at  Rome,  and  that  of  the  Sibyl  at 
Tivoli.  Excepttheir  theatres,  and 
the  little  work  generally  known  by 
the  name  of  the  Lantern  of  Demo- 
sthenes, the  Greeks  have  leffe  no 
buildings  on  a  circular  plan. 

After  the  time  of  Diocletian,  a 
new  style  prevailed  in  Italy.  The 
basilicn  of  Constantine,  as  they  ex- 
isted previous  to  their  restoration, 
and,  in  short,  almost  all  the  first 

237 


Christian  churches,  were  built  out 
of  the  materials  whicb  the  old  tem- 
ples afforded  in  abundance.  The 
basilica  of  S.  Paolo  fuori  le  mur^ 
still  contains  a  large  portion  of  the 
columns  which  had  originally  be- 
longed to  the  mausoleum  of  Adrian. 
The  style  of  these  basilicae  may 
with  propriety  be  termed  Roman- 
Gothic.  This  was  followed  by  the 
Greek-Gothic,  of  which  examples 
may  be  found  in  most  of  the  cities 
of  Italy,  as  in  St.  Mark  at  Venice, 
the  cathedral  at  Pisa,  (built  by 
Buschetto  da  Dulichio,  a  Greek  ar- 
chitect of  the  11th  century,)  and 
in  the  baptistery  and  leaning  cam- 
panile of  the  same  city :  specimens 
abound  also  in  Bologna,  Sienna, 
Venice,  Viterbo,  Rome,  &c.  They 
are  chiefly  the  works  of  Nicola  da 
Pisa  and  his  scholars. 

At  the  time  that  the  famous  ca- 
thedral of  Milan,  the  perfection  of 
the  Lombard-Gothic  style,  was  in 
hand,  Brunelleschi  was  advancing 
a  step  further,  and  had  begun  the 
restoration  of  classical  architecture 
in  the  great  cupola  of  Sta  Maria 
del  Fiore  at  Florence ;  his  prototype 
seeming  to  have  been  the  temple 
of  Minerva  Medica,  to  which  his 
work  has  sufficient  resemblance  to 
justify  the  allusion  to  it.  He  suc- 
ceeded in  his  enterprise,  and  thus 
gave  a  death-blow  to  the  Italian- 
Gothic  of  all  sorts.  L.  B.  Alberti, 
Bramante,  and  Fra.  Giocondo  re- 
stored theuse  of  the  orders;  Michael 
Angelo,  Raphael,  Sangallo,  Palladio, 
and  Scamozzi  completedthe  change; 
the  church  of  St.  Peter  rose,  and 
every  httle  city  began  to  provide 
itself  with  a  Duomo. 

The  fora  of  the  ancients  were 
large  squares  surrounded  by  por- 
ticoes, which  were  appUed  to  dif- 
ferent purposes.  Some  parts  of 
them  answered  for  market-places, 
other  parts  for  the  public  meetings 
of  the  inhabitants,  still  other  x>arts 
for  courts  of  justice.  The  forum 
also  occasionally  afforded  accom- 
modation for  the  shows  of  gladi- 


ITA 


ITALIAN  BUILDINGS. 


ITA 


atora.  Rome  contained  seventeen 
fora,  of  which  fourteen  were  used 
for  the  show  and  sale  of  goods, 
provisions,  and  merchandise,  and 
were  called  Fora  Venalia ;  the  other 
three  were  appropriated  for  dvil 
and  judicial  proceedings,  and  hence 
called  Fora  Civilia  et  Judidalia. 
Of  the  latter  sort  was  the  forum 
of  Trajan. 

The  forum  of  Julius  Caesar  was 
far  more  splendid  than  the  Forum 
Romanum:  it  cost  upwards  of 
£  800,000  sterling,  and  stood  in 
the  neighbourhood  of  the  Campo 
Vaccino,  to  the  east  of  the  temples 
of  Peace  and  of  Antoninus  and 
Faustina. 

In  the  vicinity  of  that  last  named 
was  the  forum  of  Augustus :  the 
temple  of  Mars  bis  Ultor  decora- 
ted the  centre  of  it. 

The  forum  of  Nerva,  called  also 
the  Forum  Transitorium,  begun  by 
Domitian,  was  decorated  by  Alex- 
ander Severus  with  colossal  statues 
of  the  emperors,  some  of  which 
were  equestrian.  Parts  of  this 
forum  are  still  in  tolerable  preser- 
vation. 

The  forum  of  Tnjan,  which  has 
lately  been  accurately  traced  by 
means  of  very  extensive  excavations, 
and  the  demolition  of  a  great  num- 
ber of  houses,  was  by  far  the  most 
magnificent.  The  Trajan  column 
formed  one  of  its  ornaments :  the 
architect  was  Apollodorus,  and  its 
situation  was  between  the  forum  of 
Nerva  and  the  Capitol. 

The  basilica  (a  term  now  applied 
to  the  cathedrals  of  Rome)  was 
originally  a  court  of  justice.  like 
the  forum,  it  was  furnished  with 
shops  for  the  merchants  and  bank- 
ers. In  the  place  called  the  Comi- 
tium  were  four  basilicae,  viz.  that 
of  Paulus,  the  Basilica  Opimia, 
Julia  (built  by  Vitruvius),  and  Por- 
tia :  besides  these,  the  most  impor- 
tant were  those  of  Sidnius,  Sem- 
pronius,  Caius  and  Ludus,  Antoni- 
nus Pius,  and  the  Basilica  Argen- 
tariorum,   or  of  the    goldsmiths. 

238 


Some  of  less  consideration  stood 
in  the  vidnity  of  the  Forum  Ro- 
manum. 

The  modem  halls  of  Italy  in 
some  respects  answer  the  purpose 
of  the  andent  basilicae.  Those 
most  Worthy  of  notice  are  at  Venice, 
Yicenza,  Padua,  and  Bresda. 

Near  the  Tarpeian  rock  stood 
the  famous  prison  built  by  Ancus 
Martins,  which  was  afterwards  cal- 
led Tulliana,  firom  the  additions 
thereto  by  Servius  Tullius.  The 
Curia  Hostilia,  where  the  senate 
frequently  met,  was  the  Comitium : 
at  its  entrance,  close  to  the  tem- 
ple of  Saturn,  was  the  MiUiaiiiim 
Aureum,  the  central  point  from 
which  all  the  roads  to  the  different 
provinces  diverged,  and  near  to 
which  ran  the  ^illery  constructed 
by  Caligula,  wMch  joined  the  Pa^ 
latine  and  Capitoline  hills.  It  was 
constructed  with  dghty  columns  of 
white  marble. 

The  porticoes  of  Pompey,  Au- 
gustus, Domitian,  and  Nero  were 
the  most  celebrated  of  Rome.  The 
first -named  afforded  a  refiresbing 
retreat  firom  the  sun's  rays.  The 
portico  of  Augustus  was  construct- 
ed with  columns  of  African  mar- 
ble, and  was  ornamented  with  fifty 
statues  of  the  Danaides. 

Those  of  Nero,  three  in  number, 
each  three  miles  in  length,  were 
called  Milliariae,  on  account  of  their 
extraordinary  dimensions,  forming 
a  part  of  his  palace. 

The  pyramidal  form  was  gene- 
rally applied  to  tombs.  In  the  he- 
roic ages,  a  cone  of  earth,  whose 
base  was  of  considerable  extent, 
covered  the  ashes  of  the  peraon  to 
be  commemorated.  This  was  the 
practice  of  the  eariy  ages.  Men 
were,however,  desirous  of  triumph- 
ing  over  death,  and  the  Pyramids, 
as  well  as  numberless  other  monu- 
ments, the  names  of  whose  authors 
are  now  lost,  have  proyed  the 
vanity  of  thdr  desires :  the  memory 
of  man  must  depend  upon  **  deeds 
done  in  the  flesh.'' 


ITA 


ITALIAN  BUILDINGS. 


ITA 


The  pyramid  of  Cdus  Cestiiu,  a 
trifle  compared  with  those  of  Egypt, 
is  yet  enormous,  considering  the  in- 
diyidual  to  whose  memory  it  was 
erected.  The  tower  of  Cecilia  Me- 
teUa,  called  the  Capo  di  Bove,  on 
the  Appian  way,  is  a  beautiful  speci- 
men of  art.  The  Appian,  Flami- 
nian,  and  Latin  ways  exhibit  num- 
berless sepulchres  of  an  interest- 
ing nature.  Those  which  are  found 
with  the  inscription  D.  M.,  or  Diis 
Manibus,  contain  the  ashes  of  the 
persons  whose  names  they  bear; 
but  the  others  are  mostly  cenotaphs, 
the  bodies  having  been  deposited 
elsewhere. 

Triumphal  arches  may  be  reck- 
oned among  the  luxuries  of  the 
Romans.  Nothing  which  could  tend 
to  perpetuate  the  fame  of  the  con- 
queror was  omitted  in  the  design. 
Some  of  them  were  with  two,  some 
with  three  passages.  The  richest 
were  on  the  Triumphal  way.  Those 
which  also  served  as  gates  generally 
consisted  of  two  openings,  one  for 
the  carriages  passing  out  of,  the 
other  for  carriages  passing  into  the 
city.  With  the  Greeks,  a  trophy 
erected  on  the  field  of  battle  was 
held  of  equal  importance  vrith  the 
triumphal  arch  of  the  Romans,  and 
a  breach  was  sometimes  made  in 
the  walls  to  admit  the  entry  of  the 
conqueror. 

The  Roman  senate  received  the 
conqueror  at  the  Porta  Capena, 
near  the  Tiber,  which  was  the  en- 
trance to  the  city  from  the  Appian 
way. 

The  arch  of  Augustus  at  Rimini 
has  but  a  single  passage,  about  33 
feet  wide :  it  was  crowned  with  a 
pediment,  contrary  to  the  usual 
practice.  This  was  a  beautiful 
specimen,  but  it  is  much  mutilated. 

That  called  the  arch  of  the  Gold- 
smiths  at  Romeisa  curious  example. 
It  is  very  small,  with  a  single  open- 
ing,  whose  crowning  is  a  flat  linteL 

The  arch  of  Augustus  at  Susa,  a 
small  town  just  on  the  Italian  side  (rf 
Mount  Cenis,  is  extremely  elegant. 

239 


Those  of  Aurelian  and  Janus  are 
more  singular  than  beautiful. 

The  arch  of  Pola  in  Istria  is  only 
curious  on  account  of  its  affording 
a  justification  of  the  use  of  coupled 
columns,  were  the  authority  of  the 
ancients  necessary  for  the  purpose: 
it  was  erected  by  Salvia  Posthuma 
in  honour  of  Sergius  Lepidus  and 
his  two  brothers. 

The  arch  of  Tngan  at  Ancona  is 
still  in  tolerable  preservation.  It 
has  long  since  been  stripped  of  its 
bronze  ornaments,  but  their  absence 
has  not  impaired  its  elegant  pro- 
portions. 

The  arches  of  Titus  at  Rome 
and  Trajan  at  Benevento  bear  con- 
siderableresemblance  to  each  other. 
That  of  Gavins  at  Verona,  called 
*  del  Castel  Vecchio,'  no  longer  ex- 
ists. The  precepts  of  Yitruvius 
have  been  confronted  with  his  prac- 
tice in  this  arch;  but  Vitruvius 
Cerdo,  not  Vitruvius  PoUio,  was 
the  architect. 

The  arches  of  Septimius  Severus 
and  of  Constantine  are  with  three 
openings.  The  latter  is  decorated 
vnth  ornaments  shamefullystripped 
off  from  the  arch  of  Trajan,  which, 
from  their  absurd  application,  ren- 
der the  barbarism  of  the  robber 
more  disgusting. 

Rome  formeiiy  contained  eight 
bridges.  The  Pons  Sublicius,  built 
by  Ancus  Martins  near  the  Tiber, 
was  of  timber,  so  framed  as  to  re- 
quire no  iron  bolts  or  ties  for  its 
security.  It  stood  at  the  foot  of 
the  Aventine,  and  vras  that  which 
Horatius  Codes  defended.  It  was 
replaced  by  one  of  stone  by  i£milius 
Lepidus,  and  then  had  the  name  of 
iEmilianus.  Tiberius  afterwards 
repaired  it.  Finally,  Antoninus 
Pius  rebuilt  it  of  marble,  whence  it 
obtained  the  name  of  Marmoratus. 

The  Pons  Triumphalis,  near  the 
Vatican,  is  in  ruins :  few  vestiges 
of  it  exist.  Those  who  triumphed 
passed  over  this  bridge  in  their  way 
to  the  Capitol. 

The  Pons  Fabricius  led  to  an 


ITA 


ITALIAN  BUILDINGS. 


ITA 


island  in  the  Tiber :  it  is  now  called 
Quattro  CapL  That  which  led 
from  the  tBUnd  to  the  right  bank 
of  the  river  was  called  Pons  Cestius 
or  Esquilinus :  it  was  rebuilt  during 
the  reigns  of  the  emperors  Valen- 
tinian,  Valens,  and  Gratian. 

Pons  Janicnli,  so  called  because 
it  led  to  the  Janiculum,  and  now 
known  hy  the  name  of  Ponte  Sisto, 
(from  baring  been  restored  by  Six- 
tus  IV.)  was  of  marble,  and'  built 
by  Antoninus  Pius. 

Pons  ^lios,  built  by  ^lius  Adri- 
anus,  is  still  in  existence.  It  is 
situated  close  to  the  mausoleum  of 
Adrian.  This  having  changed  its 
name  into  that  of  Castel  St.  Angelo, 
the  bridge  has  acquired  a  corre- 
sponding appellation. 

The  Pons  Milrins,  now  Ponte 
Molle,  is  a  little  way  out  of  the  city, 
on  the  road  to  Florence.  On  this 
bridge  Cicero  arrested  the  ambas- 
sadors of  the  Allobroges,  and  in  its 
vicinity  Constantine  defeated  Max- 
entius. 

Pons  Senatorius,  or  Palatinus,  is 
partly  remaining,  dose  to  the  Pa- 
tine  mount. 

Ponte  Salaro  is  over  the  Teve- 
rone,  about  three  miles  from  Rome. 

The  spans  of  the  arches  are  gene- 
rally but  small;  yet  there  are  some 
few  magnificent  exceptions,  as  in 
the  Ponte  del  Castel  Vecchio  at 
Verona.  This  consists  of  three 
arches,  the  largest  of  which  is  170 
ftet  span ;  its  two  other  arches  are 
smaller:  they  diminish  from  the 
city,  the  left  bank  of  the  river  being 
considerably  lower  than  the  right. 
The  bridge  built  by  Augustus  over 
the  Nar,  near  Nami,  on  the  Flami- 
nian  way,  was  a  single  arch  of  150 
feet  span.  In  the  later  times  of  the 
city,  bridges  were  decorated  with 
trophies,  colossal  statues,  triumphal 
arches,  and  the  like.  Such  was  the 
case  with  the  Pons  ^lius  and  the 
bridge  of  Augustus  at  Rimini. 

The  country  round  Rome  is  co- 
vered with  the  remains  of  aque- 
ducts, some  of  which  conveyed  the 

240  ~" 


¥rater  to  Rome  from  a  distance  of 
more  than  60  miles. 

The  first  aquedud  (Aqua  Appia) 
was  built,  according  to  IHodoms, 
by  Appius  Chmdins,  in  the  year  of 
the  dty  441.  The  water  which  it 
supplied  was  collected  from  the 
ndghbourfaood  of  Frascati,  and  its 
summit  was  about  100  feet  above 
the  levd  of  Rome. 

The  second  (Anio  Vetiis)  was 
begun  forty  years  after  the  last- 
named  by  M.  Curius  Dentatua,  and 
finished  by  Fulrius  Flaccna:  it  was 
supplied  from  the  country  beyond 
TivolL  Near  ^covaro  it  ia  cut 
through  a  rock  upwards  of  a  mile 
in  length,  in  which  part  it  is  5  fieet 
high  and  4  feet  wide.  The  water 
of  this  aqueduct  was  not  good,  and 
therefore  only  used  for  the  most 
ordinary  purposes. 

The  third  (Aqua  Martia)  was 
supplied  from  a  fountain  at  tiie  ex- 
tremity of  the  mountains  of  the 
Pdigni.  The  water  entered  the 
dty  by  the  Esquiline  gate.  This 
aqueduct  was  the  work  of  Quintus 
Martins. 

The  fourth  (Aqua  Tepula)  was 
supplied  from  the  vicinity  of  Fras- 
catL 

The  fifth  (Aqua  Julia)  was  about 
six  miles  long,  and  entcaned  the  dty 
near  the  Porta  Esquilina. 

The  sixth  (Aqua  Virginis)  was 
constructed  by  Agrippa  thirteen 
years  after  that  immediately  pre- 
ceding. Its  summit,  in  the  terri- 
tory of  Tusculum,  was  about  dght 
miles  from  Rome,  which  it  entmd 
by  the  Pincian  gate.  This  water 
still  bears  its  andent  appellation, 
being  called  Aqua  Vergine. 

The  seventh  (Aqua  Alaietina, 
called  also  Augusta,  from  the  use 
to  which  Augustus  intended  to  ap- 
ply it  for  supplying  his  Nanmachia,) 
was  brought  from  the  lake  whose 
name  it  bears. 

The  dghth  (Aqua  Claudia),  whose 
summit  is  about  forty  miles  from 
Rome,  was  begun  by  Caligula,  and 
completed  by  Claudius.    It  enters 


ITA 


ITALIAN  BUILDINGS. 


ITA 


the  city  at  the  Porta  Nevia,  near 
the  Esquiline  mount.  The  quality 
of  the  water  which  this  aqueduct 
supplies  is  better  than  that  of  aiiy 
of  the  others. 

The  ninth  (Anio  noTus,  to  dis- 
tinguish it  from  the  second-named 
water,)  was  begun  and  finished  by 
the  same  persons  as  the  last  men- 
tioned. It  is  the  water  of  the  Anio, 
which,  being  exceedingly  thick  and 
muddy  after  the  rains,  is  conveyed 
into  a  large  reservoir  at  some  httle 
distance  from  Rome,  to  allow  the 
mud  to  subside. 

The  Aqua  Felice  is  modem,  and 
was  erected  by  Sixtus  V.  in  1581. 

The  popes  have,  from  time  to 
time,  been  at  considerable  pains 
and  expense  in  repairing  and  re- 
newing the  aqueducts;  but  the 
quantity  of  water  delivered  is  con- 
stantly diminishing.  In  the  ancient 
city,  the  total  sum  of  the  areas  of 
the  difiTerent  pipes  (which  were 
about  an  inch  in  diameter)  through 
which  the  above  immense  quantity 
of  water  was  delivered,  amounted 
to  about  14,900  superficial  inches ; 
but  the  supply  was  subsequently 
reduced  to  1170. 

The  waters  were  collected  in  re- 
servoirs called  castelUij  and  thence 
were  conveyed  through  the  city  in 
leaden  pipes.  The  keepers  of  the 
reservoirs  were  called  castellani, 
Agrippa  alone  built  thirty  of  these 
reservoirs  during  his  aedileship. 
There  are  five  modern  ones  now 
standing  in  the  city :  one  at  the 
Porta  Maggiore,  Castello  deir  Ac- 
qua  Giulia,  dell'  Acqua  Felice,  dell' 
Acqua  Paolina,  and  that  called  the 
Fountain  of  Trevi. 

ih  later  times,  the  bath  was  al- 
ways used  by  the  Romans  before 
they  went  to  their  supper.  The 
rich  generally  had  hot  and  cold 
baths  in  their  own  houses  ;  and  it 
was  not  till  the  time  of  Augustus 
that  the  baths  assumed  an  air  of 
grandeur  and  magnificence.  They 
were  called  Thermae,  that  is,  hot 
bathSf  though  the  same  pile   of 

241 


building  always  contained  cold  as 
well  as  hot  baths.    Different  au- 
thors have  reckoned  as  many  as 
800  pubUc  baths  in  Rome.    The 
chief  were  those  of  Agrippa,  Nero, 
Titus,  Domitian,  Caracidla,  Anto- 
ninus,  and  Diocletian.    Their  ves- 
tiges indicate  the  amazing  magnifi- 
cence of  the  age  in  which  they 
were  erected.  The  pavements  were 
mosaic,  the  vaulted  ceilings  were 
gilt  and  painted,  and  the  walls  in- 
crusted  with  the  richest  marbles. 
Some  of  the  finest  and  best  pre- 
served remains  of  ancient  Greek 
sculpture  have  been  restored  to  light 
from  these  edifices.    It  was  from 
these  that  Raphael  took  the  hint 
for  his  fantastic  decorations  of  the 
Vatican,  and  the  first  restorers  of 
art  drew  their  resources. 
Dramatic  entertainments  were  first 
introduced  at  Rome  in  the  391st 
year  of  the  city.    In  ancient  times 
the  people  stood  during  the  per- 
formance.   For  a  considerable  pe- 
riod the  theatres  were  mere  tempo- 
rary buildings  constructed  of  wood. 
The  most  splendid  of  these  upon 
record  was  that  of  Marcus  iSmiiius 
Scaurus  :  it  was  magnificently  de- 
corated, and  was  capable  of  con- 
taining 80,000  persons. 

It  was  in  Pompey's  second  con- 
sulship that  the  first  stone  theatre 
was  erected :  this  accommodated 
40,000  spectators.  To  avoid  the 
animadversions  of  the  censors,  (for 
the  magistracy  did  not  yet  sanction 
theatrical  exhibitions,)  he  dedicated 
it  to  Venus. 

Several  other  theatres  afterwards 
arose:  that  of  Marcellus  can  still 
be  distinctly  traced,  and  part  of  the 
circular  fa9ade,  in  tolerable  pre- 
servation, is  singularly  elegant. 
The  theatre  of  Balbus  was  also  of 
considerable  celebrity. 

The  theatres  were  open  at  top 
to  the  heavens;  but  in  times  of  rain 
or  excessive  heat,  means  were  pro- 
vided for  covering  them  with  a 
species  of  cloth  awning,  by  which 
the  inclemencyof  the  weather  might , 


ITA 


ITALIAN  BUILDINGS. 


ITA 


I 


be  wholly  or  partially  excluded. 
Their  general  form  on  the  plan  was 
that  of  the  letter  D.  The  seats 
(jfradui)  rose  behind  each  other, 
lOce  steps.  The  front  row  was  as- 
ngpied  for  the  use  of  the  senators 
and  the  ambassadors  of  foreign 
states.  Fourteen  rows  behind  tlus 
were  reserved  for  the  equites,  and 
the  rest  were  open  for  the  public 
generally.  The  beautiful  Olympic 
^eatre,  by  Palladio,  at  Vicenza, 
was  formed  on  the  model  of  the 
ancient  Roman  theatres,  and  gives 
one  an  excellent  idea  of  their  eSfect. 
Like  the  theatres,  amphitheatres 
were  at  first  constructed  of  wood, 
and  were  only  temporary.  The  fiist 
amphitheatre  of  stone  was  built  by 
Statilius  Taurus,  at  the  desire  of 
Augustus. 

Of  all  the  monuments  of  anti- 
quity,  none  is  capable  of  creating 
such  sublime  sensations  in  the  mind 
as  the  stupendous  amphitheatre 
generally  called  the  Coliseum.  It 
was  commenced  in  the  time  of 
Vespasian,  and  completed  by  Titus. 
The  plan  of  it  is  oval,  and  its  ac- 
commodation was  for  87,000  spec- 
tators, who  could  enjoy  the  exhibi- 
tions therein  without  crowding  each 
other. 

That  part  in  which  the  gladiators 
fought  was  at  the  bottom,  and  was 
called  the  arena,  from  being  usually 
covered  vnth  sand  to  absorb  the 
blood  spilt  in  the  savage  conflicts 
for  which  it  was  used.  The  arena 
was  encircled  by  a  wall,  called  the 
podium,  which  projected  at  top. 
Thf"  vodium  was  fifteen  or  sixteen 
feet  in  height :  immediately  round 
it  sat  the  senators  and  foreign  am- 
bassadors.  As  in  the  theatres,  the 
seats  rose  at  the  back  of  each 
other:  fourteen  rows  in  the  rear  of 
the  podium  being  allotted  to  the 
equites,  and  the  remainder  to  the 
public  generally,  who  sat  on  the 
bare  stone;  but  cushions  were  pro- 
vided for  the  senators  and  equites. 
Though  open  to  the  sky,  the  build- 
ing was  occasionally  covered  by 

24^ 


means  similar  to  those  used  in  the 
theatres. 

The  amphitheatre  at  Verona  is 
still  in  excellent  preservation. 

The  Naumachik,  or  buildings  for 
the  exhibition  of  sham  naval  com- 
bats, were  somewhat  similar  on 
their  plans  to  the  circi,  to  which 
purpose  also  sometimes  these  latter 
were  appropriated.  The  amphithe- 
atres were,  moreover,  occasionally 
used  for  the  same  sort  of  display. 

Those  of  Augustus  and  Domitian 
were  the  most  magnificent. 

The  circus  was  a  long  narrow 
building,  whose  length  to  itsbreadth 
was  generally  as  five  to  one :  it  was 
divided  down  the  centre  by  an  or- 
namented barrier,  called  the  spina. 
These  buildings  were  used  for  the 
celebration  of  games,  racing,  &c. ; 
and  sometimes  also  for  making  ha- 
rangues to  the  people. 

The  first  circus  of  stone  is  attri- 
buted to  Tarquin,  and  was  situated 
between  the  Palatine  and  Aventine 
mounts. 

The  Circus  Mai^imus  was  much 
improved  and  altered  by  Julius 
Caeaiar,  who  supplied  it  with  water 
for  the  purpose  of  occasionally  using 
it  as  a  naumachia.  Augustus  made 
great  additions  to  it,  decorating  it 
with  the  famous  obelisk  which  now 
stands  in  the  Piazza  del  Popolo, 
where  it  was  placed  by  Fontana 
in  the  year  1589,  during  the 
pontificate  of  Sixtus  V.  Being 
much  dilapidated,  it  was  repaired 
under  Antoninus,  and  afterwards 
embellished  vnth  a  second  obelisk, 
which  has  found  a  resting-place  in 
front  of  the  church  of  St.  John 
Lateran,  where^it  was  set  up  by  the 
same  Fontana."^  No  vestiges  ^  this 
circus  remain. 

The  circus  of  Flaminius,  in  the 
vicinity  of  the  Pantheon  of  Agrippa, 
was  of  considerable  dimensions, 
and  very  magnificent. 

The  Circus  Agonalis  occupied  the 
site  of  what  is  now  known  by  the 
name  of  the  Piazza  Navona. 
The  circus  of  Nero,  upon  a  part 


ITA 


ITALIAN  BUILDINGS. 


ITA 


whereof  some  portion  of  the  basilica 
of  St.  Peter  is  seated,  was  a  splen- 
did building.  The  obelisk  now 
standing  in  the  open  circular  piazza 
before  St.  Peter's  belonged  to  this 
circus. 

Those  of  Florus,  Antoninus,  and 
Aurelian,  are  no  longer  e^en  in 
ruins ;  bat  that  of  Caracalla  is  suf- 
ficiently perfect  to  trace  its  plan 
and  distribution.  It  was  738  feet 
in  length. 

The  streets,  in  the  time  of  Au- 
gustus, were  narrow  and  irregular. 
After  the  great  fire  in  Nero's  reign, 
the  city  was  rebuilt  with  greater 
splendour.  The  streets  were  then 
set  out  straight,  and  considerably 
broader  than  before.  Those  houses 
wherein  several  families  dwelt  were 
called  insukB.  Dwnus  was  the  ex- 
pression^ of  a  house  occupied  by 
one  fanuly  only. 

We  know  little  of  the  form  of  the 
Roman  houses,  though  Yitruvius 
has  described  at  sufficient  length 
the  different  apartments  of  which 
they  consisted. 

The  small  houses  discovered  in  the 
ruins  of  Pompeii  can  bear  but  little 
if  any  resemblance  to  the  houses  of 
the  opulent  inhabitants  of  Rome. 
The  most  celebrated  were  those  of 
the  Gordians,  P.  Valerius  Publicola, 
Caesar,  Sallust,  Mecaenas,  Cicero, 
Verres,  Augustus,  and  Lucullus. 
The  Domus  aurea  of  Nero  was 
probably  the  most  magnificent  in 
Rome*  The  villa  of  Adrian,  at 
Tivoli,  was  so  extensive,  that  it  al- 
most deserved  the  name  of  a  city. 
Immense  ruins  of  the  palaces  of 
the  Caesars  are  still  to  be  seen. 

Rome  was  decorated  with  num- 
berless piUars.  The  most  remark- 
able are  fortunately  in  an  excellent 
state  of  preservation,  namely,  those 
of  Trajan  and  Antoninus. 

The  column  of  Trajan  stood  in 
that  emperor's  forum :  it  is  about 
12  feet  in  diameter  at  its  base,  and 
(including  the  pedestal)  is  about 
125  feet  in  height.  The  ascent  to 
the  gallery  on  the  top  of  the  abacus 

243 


of  its  capital  is  by  185  steps,  each 
2  feet  9  inches  long,  winding  round 
the  column,  and  lighted  by  40  open- 
ings. A  colossal  statue  of  Tnjan 
formerly  crowned  the  top ;  but  St. 
Peter  has  long  since  deposed  the 
emperor. 

The  column  of  Antoninus  is  176 
feet  high,  its  number  of  steps  106, 
with  56  openings  for  the  admission 
of  light.  Sixtus  y.  caused  its  pe- 
destal to  be  cased,  when,  in  1589, 
the  pillar  was  under  repair.  It  was 
this  pontiff  who  elevated  St.  Peter 
to  his  situation,  as  well  on  this  as 
on  the  Trajan  column. 

The  great  sewers  of  Rome  are 
reputed  to  have  been  the  work  of 
Tarquinius  Priscus.  The  Cloaca 
Maxima,  which  still  carries  some  of 
the  filth  and  waste  water  of  Rome 
into  the  Tiber,  was  the  work  of 
Tarquinius  Superbus. 

The  pubhc  ways  were  not  only 
some  of  the  most  stupendous,  but 
also  the  most  useful  of  the  Roman 
works. 

The  first  road  which  the  Romans 
paved  was  the  Via  Appia,  so  called 
because  it  was  executed  by  order 
of  Appius  Claudius.  He  carried  it 
as  far  as  Capua,  whence  it  was  af- 
terwards continued  to  Brundusium 
— in  all,  a  distance  of  350  miles. 
It  is  still  entire  in  many  places, 
though  more  than  twenty  centuries 
have  elapsed  since  its  construction. 
It  was  properly  called  'Regina 
Viarum.' 

The  Via  Numida  led  to  Brindis 
(Brundusium);  the  Via  Plaminia 
to  Rimini  and  Aquileia;  the  Via 
Aurelia  was  along  the  coast  of 
Etruria ;  the  Via  Cassia  ran  to  Mo- 
dena,  between  the  Flaminian  and 
Aurelian  ways;  the  Via  i£milia 
extended  from  Rimini  to  Piacenza. 

The  smaller  ways  were,  the  Via 
Praenestina  to  Palestrina  (the  an- 
cient Praeneste) ;  Tiburtina  to  Ti- 
voli; Ostiensis  to  Ostia;  Laurentina 
to  Laurentum,  south  of  Ostia ;  Sa- 
laria,  &c.  The  cross-roads  were 
called  Diverticula. 


ITA 


ITALIAN  ARCHITECTURE. 


IVO 


Italian  architecture  comprises  so 
many  diversities  that  it  is  hardly 
possible  to  affix  to  it  any  thing  like 
a  precise  character,  except  by  limit- 
ing it  to  a  particular  epoch  or 
school,  or  to  one  special  class  of 
buildings ;  and  even  then  the  ex- 
ceptions may  be  more  numerous 
than  the  examples  referred  to  as  a 
standard.  With  many  vices  and 
defects,  it  possesses  many  excel- 
lences and  recommendations,  and  a 
variety  of  resources,  which  render 
it  capable  of  being  turned  to  far 
greater  account  than  hitherto  has 
been  done.  But  if  on  the  one 
hand  it  affords  much  scope  to  the 
architect,  it  calls  on  the  other  for 
the  exercise  of  discriminating  taste ; 
one  that  not  only  rejects  what  is 
positively  bad,  but  is  capable  of 
re-combining  all  the  better  ele- 
ments of  the  style,  so  as  to  impart 
to  them  originality  and  freshness, 
without  forfeiting  what  is  valuable 
in  and  characteristic  of  the  style 
itself;  so  that,  instead  of  appearing 
contrary  to  its  genius,  the  novel 
forms  and  effects  that  may  be  pro- 
duced shall  seem  to  be  beauties, 
which  have  merely  been  lying  la- 
tent, and  waiting  for  a  discoverer 
to  bring  them  to  light.  A  style  is 
to  be  judged  of,  not  only  retro- 
spectively by  what  it  has  produced, 
but  prospectively  also,  according  to 
what  it  is  capable  of  supplying. 
Nevertheless,  so  far  from  being  at 
all  encouraged,  such  view  of  the 
subject  is  kept  out  of  sight  as  much 
as  possible;  and  precedent  is  al- 


JAC 

Jack,  an  instrument  for  raising  a 
heavy  weight  through  a  short  dis- 
tance ;  it  consists  of  a  strong  piece 
of  wood,  with  an  iron  rack  which  is 
moved,  by  wheels  fixed  inside  the 
wood,  from  a  handle  outside 

Jack,  in  navigation,  a  flag  or  colour ; 
a  small  union  flag 

Jak  woodf  a  native  of  India,  is  im- 
ported in  logs  from  3  ft.  to  5  ft. 


lowed  to  usurp  such  sway,  that  any 
departure  from  it,  no  matter  in 
what  spirit,  is  liable  to  be  con- 
founded with  and  reprobated  as 
capricious  innovation,  although  the 
one  proceeds  quite  in  an  opposite 
direction  to  the  other. 

Italian  church  (the),  in  the  front  or 
facade,  is  never  true  to  the  internal 
structure ;  it  is  always  divided  into 
two  apparent  stories,  by  two  heights 
of  pillars,  or  pilasters,  and  by  win- 
dows, or  alcoves ;  but  the  greater 
number  of  churches  in  Rome  have 
the  outward  look  of  large  dwelling- 
houses,  a  highly  ornamented  centre 
and  wings  less  so,  with  two  or  three 
ranges  of  windows,  not  diflTering 
from  a  habitable  house 

Ivory  is  first  mentioned  in  the  reign 
of  Solomon  :  ivory  was  used  in  de- 
corating those  boxes  of^perfumes 
whose  odours  were  employed  to 
exhilarate  the  king's  spirits.  It  is 
probable  that  Solomon,  who  traded 
in  India,  first  brought  thence  ele- 
phants and  ivory  into  Judea.  Ca- 
binets and  wardrobes  were  orna- 
mented with  ivory  by  marquetry- 
work.  These  were  called  '  houses 
of  ivory.' — "Eighty  more  chests  of 
ivory,  for  your  use  and  pleasure,'' 
are  enumerated  in  the  letter  which 
accompanied  the  very  remarioible 
tribute  of  the  Ethiopian  queen, 
Candace,  to  Alexander  the  Great. 

Ivory-black  and  bone-black,  ivory  and 
bone  charred  to  blackness  by  strong 
heat  in  closed  vessels ;  if  skilfully 
prepared,  they  are  eligible  for  oU 
and  water  painting 


JAM 

diameter ;  the  grain  is  coarse  and 
crooked:  used  in  cabinet-work, 
marquetry,  and  turning,  and  also 
for  brush-backs 

Jamb,  in  building,  a  supporter  on 
either  side,  as  the  posts  of  a  door 

Jambs,  the  side  pieces  of  any  open- 
ing in  a  wall,  which  bear  the  piece 
that  discharges  the  superincumbent 
weight  of  such  waU 


JAN 


JUSTICE,  COURTS  OF. 


JUS 


Janta,  a  machine  extensively  nsed 
in  Bengal  and  other  parts  of  India, 
to  raise  water  for  the  irrigation  of 
land.  It  consists  of  a  hollow 
trough  of  wood,  ahout  15  ft.  long, 
6  inches  wide,  and  10  inches  deep, 
and  is  placed  on  a  horizontal  heam 
Ijing  on  bamboos  fixed  in  the  bank 
of  a  pond  or  river :  one  end  of  the 
trough  rests  upon  the  bank,  where 
a  gutter  is  prepared  to  carry  off  the 
water,  and  the  other  end  is  dipped 
in  the  water  by  a  man  standing  on 
a  stage,  plunging  it  in  with  his  foot. 

/oittui,  among  the  Romans,  the  street- 
door  of  a  private  house 

Japanning^  the  art  of  painting  and 
varnishing  on  wood,  leather,  metal, 
or  paper,  after  the  manner  of  the 
Japanese 

Jaune  Min^rale.  This  pigment  is  a 
chromate  of  lead,  prepared  in  Paris. 
The  chrome-yellows  have  obtained 
other  names  from  places  or  per- 
sons  from  whence  they  have  been 
Inought,  or  by  whom  they  have 
been  prepared,  such  as  ^aune  de 
Cologne,  &c. 

Je88e  (the  root  of),  a  term  applica- 
ble  to  the  genealogy  of  Christ,  as 
affording  subjects  for  the  painter, 
sculptor,  or  embroiderer 

Jet  d^EaUj  a  French  expression,  sig- 
nifying a  fountain  that  throws  up 
water  to  some  height  in  the  air 

fettyt  a  part  of  a  building  that  pro- 
jects beyond  the  rest,  and  over- 
hangs the  wall  below,  as  the  upper 
stories  of  timber-houses,  bay-win- 
dows, pent-houses,  small  turrets  at 
the  comers,  &c. 

Jetty,  a  projecting  erection  into  the 
sea,  partaking  something  of  a  pier, 
mostly  constructed  of  timber,  with 
open  spaces  for  the  sea  to  play 

Jewry,  a  district,  street,  or  place  or 
locality,  in  which  Jews  formerly 
resided 

Jib,  the  overhanging  part  of  a  crane, 
or  a  triangular  frame  with  a  pulley 
at  the  end,  for  the  chain  to  pass 
over  which  leads  from  the  crane 

Jib,  in  navigation,  the  foremost  sail 
of  a  ship 


Jib^oom,  a  spar  mn  out  from  the 
bowsprit 

Jigger,  a  machine  consisting  of  a  piece 
of  rope  about  5  feet  long,  with  a 
block  at  one  end  and  a  sheaf  at  the 
other,  used  to  hold  on  the  cable 
when  it  is  heaved  into  the  ship  by 
the  revolution  of  the  windlass 

Jigging,  in  Cornwall,  a  method  of 
dressing  the  smaller  copper  and 
lead  ores,  by  the  motion  of  a  wire 
sieve  in  a  kieve  or  vat  of  water 

Joggle,  a  term  in  the  business  of  ma- 
sonry, the  art  of  joining  and  fitting 
the  stones  together 

Joinery,  the  art  of  joining,  compre- 
hends aU  the  fixed  wood-work  in- 
tended for  ornament  or  convenience 
in  the  interior  of  a  house 

Joint,  the  interstices  between  the 
stones  or  bricks  in  masonry  and 
brick-work  are  so  called 

Joitts,  in  carpentry,  the  secondary 
beams  of  a  floor;  those  pieces  of 
timber  framed  into  girders  and 
summers,  on  which  the  boards  of 
the  floor  are  laid 

Journal,  a  bearing  of  a  shaft  when  it 
is  between  the  points  where  the 
powers  and  resistance  are  appUed ; 
a  bearing  subject  to  torsion 

Jube,  anciently,  the  rood-loft  or  gal- 
lery over  the  entrance  into  the 
choir  of  a  cathedral  or  church 

Jiyumentum,  the  lentil  of  a  door 

Jumper,  a  long  borer  used  by  one 
person 

Jumper  wood,  an  aromatic  and  very 
durable  kind  of  wood 

Junk -ring,  a  ring  fitting  a  groove 
round  a  piston,  to  make  it  steam- 
tight.  The  ring  is  turned  accu- 
rately to  the  diameter  of  the  cylin- 
der, and  slightly  hammered  all 
round  on  the  inside  to  increase  its 
elasticity ;  it  is  then  cut  open,  and 
put  in  its  place :  springs  are  some- 
times used  for  pressing  it  outward. 

Justice  {Courts  of).  These  places 
(according  to  Palladio)  were  an- 
ciently called  basilicsB,  where  the 
judges  attended  to  administer  jus- 
tice, and  where,  sometimes,  great 
and  important  affairs  were  trans- 


245 


KAG 


KEY-STONE. 


KIN 


acted:  whence  we  read,  that  the 
tribunes  of  the  people  caused  to  be 
taken  away  a  column  that  inter- 
rupted their  benches,  from  the  Ba- 


KAG 

Kaob,  andentlj  applied  to  chantry 
chapels  enclosed  with  lattices  or 
screen-work 

KaoUn,  aluminous  earth ;  the  porce- 
lain earth  of  the  Chinese 

Keuert  in  Cornwall,  a  sieve 

Kedffingi  in  navigation,  a  term  nsed 
when  a  vessel  is  brought  up  or 
dovm  a  narrow  river  or  over  a  bar 

Keelf/ibe,  in  ship-building,  a  strong 
thick  piece  of  timber  bolted  to  the 
bottom  of  the  real  keel,  which  is 
very  useful  in  preserving  it 

Keeb,  in  navigation,  smaU  vessels  that 
carry  coals  dovm  the  river  Tyne 

Keehon,  in  ship-building,  the  piece 
of  timber  attached  to  a  ship's  keel 

Keept  the  chief  tower  or  dungeon  of 
a  Norman  castle 

Keeping f  in  painting,  is  the  observance 
of  a  due  proportion  in  the  general 
light  and  colouring  of  a  picture,  so 
ihtX  no  part  be  too  vivid  or  more 
glaring  than  another,  but  a  proper 
harmony  and  gradation  be  evident 
in  the  whole  performance 

Kept  doum  is  a  term  implying  gloomi- 
ness of  tint,  or  an  object  so  shaded 
vrith  fuscous  colour  that  its  form 
can  scarcely  be  determined ;  which 
object  is  not  intended  to  be  seen 
by  the  spectator  until  he  has  re- 
gularly observed  all  the  other  parts 
of  the  painting,  but  which  is  ne- 
cessary to  the  composition 

Kermes  laket  an  ancient  pigment,  per- 
haps the  earliest  of  the  European 
lakes :  the  name  is  probably  derived 
from  the  alkermes  of  the  Arabians, 
fi:om  Kerman,  the  ancient  Carma- 
nia,  on  the  borders  of  Persia 

Kerned,  a  term  applied  to  a  heap  of 
mundic  or  copper  ore  hardened  by 
lying  exposed  to  the  sun 

Ketch,  in  navigation,  a  vessel  vrith 
with  masts  and  sails 

Kevels,  in  ship-building,  answer  the 


silica  Portia ;  which  was  at  Rome, 
near  the  temple  of  Romulus  and 
Remus,  and  is  now  the  church  of 
St.  Cosmus  and  Damianus. 


KIN 

purpose  of  timber-heads,  and  are 
sometimes  fixed  to  the  spirketing 
on  the  quarter-deck,  when  the  tim^^ 
ber-heads  are  deficient 

Key,  a  term  applied'  to  a  painting 
when  one  object,  generally  the  prin- 
cipal one,  is  so  worked  up  to  its 
proper  tone,  strength  of  colour, 
&c.,  that  the  painter  is  compelled 
to  finish  the  whole  piece  in  a  mas> 
terly  manner :  this  is  said  to  have 
been  the  practice  of  Titian 

Key-grooving  maehtfUf  a  machine  for 
cutting  the  grooves  or  key-ways  in 
the  boss  of  a  wheel  to  be  fixed  on 
a  shaft 

Keyserew,  a  lever  used  for  turning 
screws 

Key-stone,  the  stone  in  an  arch  which 
is  equally  distant  from  its  springing 
extremities.  In  a  circular  arch 
there  Will  be  tWo  key-stones,  one 
at  the  summit  and  the  other  at  the 
bottom  thereof:  in  semi-circular, 
semi-elliptical  arches,  &c.,  it  is  the 
highest  stone,  firequently  sculp- 
tured on  the  face  and  return 
sides. 

Kiabooca  wood,  or  Amboyna  wood, 
imported  from  Sincapore,  is  Tery 
ornamental,  and  is  used  for  small 
boxes  and  writing-desks,  and  other 
ornamental  works 

Kibbal,  a  bucket  in  which  ore  is  raised 
from  the  mines 

Kieve,  a  vat  or  large  iron-bound  tub 
for  washing  of  ores 

Kilkenny  marble,  a  fine  black  marble, 
full  of  shells  and  corolloid  bodies 

KiUoM,  a  clay  slate  occurring  in  dif- 
ferent parts  of  a  mine 

Killepe,  anciently  a  gutter,  groove,  or 
channel 

Kilogramme  (pronounced  Kilo),  a 
French  weight,  equivalent  to  2  lbs. 
3  oz.  5  drs.  13  grs.  avoirdupois 

King-at-arma,  in  heraldry,  a  principal 


KIN 


KYANIZING. 


KTA 


officer  at  arms,  of  whom  there  are 
three  :  Garter,  Norroy,  and  Claren- 
cleux 

Kinff-postf  thp  middle  post  of  a  roof, 
standing  in  the  tie-beam  and  reach- 
ing up  to  the  ridge ;  it  is  often 
formed  into  an  octagonal  column 
with  capital  and  base,  and  smaU 
struts  or  braces,  which  are  slightly 
curved,  spreading  from  it  above  the 
capital  to  some  other  timbers 

Kingston's  valves  a  flat  valve  form- 
ing the  outlet  of  the  blow-off  pipe 
of  a  marine  engine  :  it  opens  from 
the  side  of  the  vessel  by  turning  a 
screw 

King  tDOod,  called  also  violet  wood,  is 
imported  from  the  Brazils :  it  has 
violet-streaked  tints,  and  is  used  in 
turnery  and  small  cabinet-work 

Kirk,  church,  a  term  still  used  in 
Scotland,  formerly  so  in  England 

Klinometer,  or  Climometer,  an  instru- 
ment contrived  to  measure  the  in- 
clinations of  stratified  rocks,  the 
declivity  of  mountains,  and  the  dip 
of  mineral  strata 

KneCf  a  term  sometimes  used  for  the 
return  of  the  drip-stone  at  the 
spring  of  an  arch 

Knees,  in  ship  -  building,  are  the 
crooked  pieces  of  oak  timber,  or 
iron,  which  secure  the  beams  to 
the  side  of  the  ship 

Knight-heads  or  bollard-timbers,  the 
timbers  on  each  side  nearest  the 
stem,  and  continued  high  enough 
to  secure  the  bowsprit 

Knits,  small  particles  of  lead  ore 

Knockvngs,  lead  ore  with  spar,  as  cut 
from  the  veins 

Knot  ot  Knob,  a  boss;  a  round  bunch 
of  leaves  or  flowers,  or  other  orna- 
ment of  a  similar  kind 

Knuckle -timber,  the  foremost  top 
timber  in  the  ship  that  forms  the 
buck-head;  the  timbers  abaft  it, 
as  far  as  the  angle  is  continued, 
may  be  called  knuckle-timbers 

Krems,  Crems,  or  Kremnitz  ithite, 
a  white  carbonate  of  lead,  named 
from  Crems  or  Krems,  in  Austria ; 
also  called  Vienna  white 

Kyanizing  and  Bumettizing.     Kyan- 


izing  is  a  simple  process  by  means 
of  which  timber,  canvas,  and  cord- 
age, &c.  may  be  preserved  from 
the  effect  of  dry-rot,  and  seasoned 
in  a  very  short  time.  It  was  in-' 
vented  by  Mr.  Kyan,  who  obtained 
a  patent  for  it,  which  was  purchased 
by  a  company  called  the  *  Anti- 
Dry-rot  Company,'  constituted  and 
empowered  by  Act  of  Parliament. 

The  timber  is  prepared  as  fol- 
lows :  a  wooden  tank  is  put  together 
80  that  no  metal  of  any  kind  can 
come  in  contact  with  the  solution 
when  the  tank  is  charged. 

The  solution  consists  of  corrosive 
sublimate  and  water,  in  the  pro- 
portion of  1  tb.  of  corrosive  subli- 
mate to  10  gallons  of  water  as  a 
maximum  strength,  and  1  lb.  to  15 
gallons  as  a  minimum,  according  to 
the  porosity  or  absorption  of  the 
timber  subjected  to  the  process. 

Oak  and  fir  timber  absorb  nearly 
alike,  but  the  domestic  woods,  such 
as  beech,  poplar,  elm,  &c.  are  more 
porous. 

An  hydrometer  will  mark  accu- 
rately the  strength  of  the  solution, 
water  being  0°  {vide  diagram) ;  then, 
when  the  hydrometer  sinks  to  6^, 


Water. 


—  1  lb.  of  cor.  sub.  to 
15  gal.  of  water. 

XoLH  1  lb.  to  1<^  gal.  do. 


15 


ao 


'  ~  1  lb.  to  5  gal.   do. 


A 


V 


247 


KYA 


KYANIZING  AND  BURNETTIZING. 


KYA 


it  denotes  that  the  solution  con- 
tains Itb.  of  sublimate  to  15  gallons 
of  water ;  when  it  rises  to  17°,  lib. 
of  sublimate  to  5  gallons. 

As  a  general  rule,  when  it  stands 
midway  between  5°  and  10°,  the 
solution  will  be  the  proper  strength. 
The  oorroslTe  sublimate  will  dis- 
solve best  in  tepid  water. 

The  period  required  for  satu- 
rating  timber  depends  on  its  thick- 
ness: 24  hours  are  required  for 
each  inch  in  thicknessi  for  boards 
and  small  timbers. 

The  timbers,  after  saturation, 
should  be  placed  under  a  shed  or 
cover  from  the  sun  and  rain,  to  dry 
gradually. 

In  about  14  days,  deals  andtimber 
not  exceeding  3  inches  in  thickness 
will  be  perfectly  dry  and  seasoned, 
and  fit  for  use.  Large  timbers  will 
require  a  proportionate  time,  ac- 
cording to  their  thickness. 

The  solution  may  be  used  ad 
infinitum,  as  its  strength  is  nut 
diminished ;  but  it  will  be  advisable 
to  ascertain  occasionally  by  the 
hydrometer  that  it  contains  the  re- 
quired proportions  of  corrosive  sub- 
limate and  water. 

Professor  Faraday  and  the  late 
Dr.  Birkbeck  have,  with  many 
other  scientific  men,  testified  in  the 
strongest  manner  to  the  efficacy  of 
this  solution.  The  former  says, 
with  respect  to  the  penetration  of 
the  solution  by  steeping,  without 
pressure,  that  it  may  be  tested  by 
the  application  of  a  drop  of  hydro- 
sulphuret  of  ammonia,  which  will 
turn  black  on  meeting  with  the 
mercury. 

In  the  cube  of  elm,  the  corrosive 
sublimate  may  be  traced  by  the 
above  test  to  the  depth  of  from 
^  to  ^  of  an  inch ;  by  the  test  of 
voltaic  action,  from  f  to  1  inch. 

In  the  cube  of  oak,  with  the  same 
test,  it  was  found  at  ^  of  an  inch, 
but  irregular,  and  apparently  fol- 
lowed the  fissures  of  the  wood ;  by 
voltaic  action,  not  quite  so  far  as 
in  the  elm. 

248  ~  " 


In  the  cube  of  fir,  the  penetra- 
tion was  the  least  by  the  common 
test,  i  to  ^  of  an  inch ;  by  voltaic 
action,  ^  of  an  inch,  the  turpentine 
in  the  wood  probtfbly  being  the 
obstruction  to  penetration. 

From  this  testimony  it  is  evident 
that  when  pressure  is  not  used,  the 
timber  should  be  worked  up  into 
the  form  required  before  immersion. 

The  patentees  or  company,  who 
have  ako  the  means  of  saturating 
with  hydraulic  pressure  at  their 
establishment,  similar  to  that  at 
Portsmouth  Dockyard,  under  Sir 
WilUam  Burnett's  process,  grant 
licenses  at  the  rate  of  bs.  per  cubic 
foot  internal  dimensions  of  the  tank, 
and  sell  corrosive  sublimate  at  4«. 
per  tb. 

l^ib.  is  sufficient  to  saturate  a 
load  of  timber  of  50  cubic  feet,  at 
the  rate  of  1  ib.  of  sublimate  to  15 
gallons  of  water. 

The  process  has  been  for  several 
years  extensively  used  for  sleepers 
on  railroads. 

Several  of  the  sleepers  on  the 
South  Western  Railway,  which  had 
been  subjected  to  this  process,  were 
taken  up,  owing  to  their  being 
decayed,  particularly  in  the  chalk 
districts.  It  was,  however,  stated 
by  the  engineer  that  they  had 
been  steeped  at  the  company's 
works  in  a  hasty  manner,  and  that 
he  did  not  consider  it  conclusive 
against  the  process;  that  he  had 
never  seen  any  wood  decayed  that 
had  been  steeped  by  the  patentees. 
It  is  also  said  that  neither  Kyan's, 
Burnett's,  nor  Payne's  process,  can 
resist  the  combined  effects  of  mois- 
ture and  great  heat,  say  80°  Fahr. 

BURNETTIZING. 

Bumettizing  is  the  process  by 
means  of  which  timber,  felt,  can- 
vas, cordage,  cottons,  and  woollens, 
may  be  preserved  from  dry-rot, 
mildew,  moth,  and  premature  de- 
cay. It  takes  its  name  frt>m  its 
inventor.  Sir  William  Burnett,  M.D., 
K.  C.B.,  F.  R.  S.,  of  the  Navy,  who 
took  out  a  patent  for  it  in  1837. 


KYA 


KYANIZING  AND  BURNETTIZING. 


KYA 


It  consists  in  immersing  the 
yarious  substances  above  enume- 
rated in  a  solution  of  chloride  of 
zinc  and  water  in  a  wooden  tank, 
in  the  proportion  of  1  tb.  of  chlo- 
ride of  zinc  to  4  gallons  of  water 
for  wood,  and  1  ib.  of  the  chloride 
to  5  gallons  of  water  for  the  re- 
mainder of  the  articles,  with  the 
exception  of  felt,  which  requires 
1  tb.  of  the  chloride  to  2  gallons  of 
water. 

Three-inch  deals  require  to  re- 
main in  the  tank  or  cistern  six 
days,  and  all  other  woods  in  the 
same  proportion,  or  two  days  per 
inch.  They  are  then  taken  out  and 
put  under  a  shed,  on  their  ends,  to 
dry,  and  require  for  this  purpose 
from  fourteen  days  to  three  months, 
according  to.  the  thickness  of  the 
wood,  when  they  are  fit  for  use. 

The  timber  should  be  reduced  to 
the  scantling  required  for  use  before 
it  is  subjected  to  this  process. 

Canvas,  yam  for  cordage,  cottons, 
and  woollens,  require  to  be  sus- 
pended in  the  solution  for  forty- 
eight  hours. 

The  process,  however,  with  re- 
spect to  timber,  is  much  more  ex- 
peditiously and  effectively  done  by 
hydraulic  pressure  in  Her  Majesty's 
dockyard  at  Portsmouth,  where 
large  quantities  of  timber,  &c.,  are 
prepared  for  the  use  of  the  Royal 
Navy  at  the  various  dockyards  in 
England,  particularly  for  ships' 
magazines. 

There  is  a  large  vn'ought-iron 
tank,  52  feet  in  length  and  6  feet 
in  diameter,  with  a  door  2  feet  6 
inches  x  2  feet  at  each  end  for 
loading. 

Timber  of  all  sizes  and  descrip- 
tions is  put  into  this  cylinder,  which' 
contains  about  twenty  loads.  As 
soon  as  it  is  filled,  and  the  doors 
well  secured  both  against  external 
and  internal  pressure,  the  air  is  ex- 
hausted in  the  cylinder,  and  also  in 
the  timber,  by  means  of  an  air- 
pump  worked  by  a  small  rotatory 
engine  of  lO-horse  power,  on  the 


Earl  of  Dundonald's  principle,  un- 
til the  barometer  stands  at  27^: 
the  valve  leading  to  the  air-pump 
is  then  shut,  and  the  cock  of  a  pipe 
leading  from  the  tank,  filled  vnth 
the  solution,  to  the  cylinder,  is 
turned:  the  solution  rushes  into 
the  cylinder  to  fill  up  the  partial 
vacuum,  and  about  half-fills  it,  when 
the  cock  is  turned,  and  the  air- 
pump  again  set  to  work  until  the 
barometer  stands  at  27i^t  when  the 
same  process  is  repeated,  and  the 
cylinder  nearly  filled  ■mih  the  so- 
lution. 

A  pressure  of  150  lbs.  per  square 
inch  is  then  obtained  by  means  of 
a  Bramah  forcing-pump,  connected 
with  an  iron  copper  or  reservoir, 
filled  ynth  the  solution,  and  com- 
municating with  the  cylinder  by 
means  of  a  pipe.  This  is  woiised 
by  hand  until  a  valve  placed  on  the 
top  of  the  cylinder,  and  loaded  to 
the  required  gauge,  begins  to  lift. 

The  timber  is  then  left  in  the 
cylinder,  subject  to  this  pressure, 
for  eight  hours,  which  is  considered 
sufficient  for  the  largest  logs,  even 
in  a  rough  state.  The  solution 
being  then  drawn  off  into  the  tank, 
and  the  timber  taken  out  of  the 
cylinder,  it  is  re-loaded,  and  the 
process  repeated:  the  same  solu- 
tion is  used  for  two  months,  when 
fresh  is  prepared. 

The  same  process  for  drying  the 
timber  thus  saturated  is  adopted, 
as  before  stated.  Canvas,  felt,  and 
yam,  &c.  are  not  subjected  to 
pressure. 

The  felt  is  used  as  a  lining  to  the 
magazines  of  men-of-war,  between 
two  thicknesses  of  wood ;  also  to 
cover  over  the  steam  boilers  of 
steam  ships :  it  is  said  to  be  ren- 
dered much  less  liable  to  combus- 
tion by  the  process. 

It  is  stated  that  in  tropical  cli- 
mates, more  especially  in  Africa, 
the  saturated  canvas  has  stood  the 
climate,  when  the  unprepared,  under 
similar  circumstances,  has  rapidly 
decayed. 


249 


15 


i^lMM*M«*MM^Mri 


LAB 


LAKE,  COLOUR. 


LAC 


Both  Bumettizing  and  Kyan^ 
izing  offer  great  advantages  to  the 
engineer : 

1st.  Wood  of  every  kind  is  ren- 
dered more  durable,  and  is  rapidly 
seasoned. 

2ndl7.  It  brings  into  general 
use  larch,  poplar,  and  a  variety  of 
other  indigenous  woods,  as  weU  as 
American  pine,  &c.,  which,  with- 
out the  process,  from  being  liable 
to  rapid  decay,  and  being  much 
inferior  to  Baltic  timber,  are  sel- 
dom used  in  public  buildings. 

To  the  military  engineer,  these 
inventions  offer  stiU  greater  advan- 
tages.   He  is  frequently  called  on. 


LAB 

Laburnvh,  a  small  dark-greenish 
broom-wood,  is  sometimes  used  in 
ornamental  cabinet-work 

Labyrinth  f  a  series  of  hedges,  mounds, 
or  walls,  with  numerous  winding 
passages;  intricate  and  winding 
walks  in  a  garden 

Lacingt  a  piece  of  compass  or  knee- 
timber,  fayed  to  the  back  of  the 
figure  and  the  knee  of  the  head 
of  a  ship,  and  bolted  to  each 

Lacker,  a  varnish  applied  upon  tin, 
brass,  and  other  metals,  to  preserve 
them  from  tarnishing,  and  to  im<^ 
prove  their  colour 

Lac  lake  is  prepared  from  lac,  an 
Indian  drug.  It  resembles  cochi- 
neal and  kermes,  being  the  produc- 
tion of  a  species  of  insect.  Its  co- 
lour is  rich,  transparent,  and  deep, 
— less  brilliant,  and  more  durable 
than  those  of  cochineal  and  kermes, 
but  inferior  in  both  these  respects 
to  the  colour  of  madder. 

Laconicum,  among  the  ancients,  the 
semicircular  end  of  a  bath ;  a  cir- 
cular stove,  for  the  purpose  of 
heating  the  sudatories,  or  sweating- 
rooms  of  a  bath :  the  use  of  the 
dry  bath  is  said  to  have  been  pre- 
valent among  the  Lacedsemonians 

Lacquer,     See  Lacker, 

Lacwnaria,  the  ceiling  of  the  ambu- 

250  ~~~ 


in  distant  colonies,  to  construct 
block-houses,  stockades,  bridges, 
and  barracks,  where  the  only  ma- 
terial to  be  had  in  abundance  is 
the  tree  standing  in  the  forest :  to 
him  a  few  pounds  of  either  ingre- 
dient would  be  invaluable^  by  en- 
abling him  to  season  and  render 
durable  the  timber  a  few  days  alter 
it  was  cut  down,  and  thus  provide 
him  with  the  ready  means  of  ren- 
dering a  distant  post  tenable  in  a 
short  time  by  a  small  body  of  men, 
with  the  additional  satisfaction  of 
knowing  that  the  work  thus  hastily 
erected  would  be  found  to  be  of  a 
permanent  nature. 


LAC 

latory  around  the  cella  of  a  tem- 
ple or  of  the  portico.  The  beams, 
which  extended  from  the  walls  to 
the  entablature,  were  intersected  by 
others  ranged  longitudinally:  the 
square  spaces  made  by  these  inter- 
secting beams  were  contracted  to- 
wards the  top,  and  were  sometimes 
closed  with  single  stones,  which 
might  occasionally  be  removed. 

Lacunars  J  in  architecture,  are  panels  or 
coffers  in  the  ceilings  of  apartments, 
and  sometimes  in  the  soffits  of  the 
corona  of  the  Ionic,  Corinthian,  and 
Composite  orders 

Lady-chapel,  a  chapel  dedicated  to  the 
blessed  Virgin 

Lake  (colour),  a  name  derived  from  the 
lac  or  lacca  of  India,  is  the  cogno- 
men of  a  variety  of  transparent  red 
and  other  pigments  of  gpreat  beauty, 
prepared  for  the  most  part  by  pre- 
cipitating coloured  tinctures  of  dye- 
ing drugs  upon  alumine  and  other 
earths,  &c.  The  lakes  are  hence  a 
numerous  class  of  pigments,  both 
with  respect  to  the  variety  of  their 
appellations  and  the  substances 
from  which  they  are  prepared.  The 
colouring  matter  of  common  lake 
is  Brazil  wood,  which  affords  a  very 
fugitive  colour.  Superior  red  lakes 
are  prepared  from  cochineal,  lac. 


LAM 


LANDSCAPE  GARDENING. 


LAN 


and  kertnes ;  but  the  best  of  all  are 
those  prepared  from  the  root  of  the 
rubia  tinctoriay  or  madder -plant. 
See  Zoc  lake. 

Lama,  in  mining,  slime  or  schelm 

LanUniBj  the  extremely  thin  plates  or 
layers  of  metal  which  compose  the 
solid  metal 

Laminable,  a  term  applied  to  metal 
which  maybe  extended  by  passing  it 
between  steel  or  hardened  (chilled) 
cast-iron  rollers 

Laminated,  disposedin  layers  or  plates. 
When  metal  can  be  readily  extended 
in  aU  directions,  under  the  ham- 
mer, it  is  said  to  be  malleable,  and 
when  in  fillets  under  the  roUing- 
press,  it  is  said  to  be  laminable. 

Lamp-black  is  a  smoke-black,  being  a 
soot  of  resinous  woods  obtamed  in 
the  manufacturing  of  tar  and  tur- 
pentine. It  is  a  pure  carbonaceous 
substance  of  a  fine  texture,  intensely 
black  and  perfectly  durable,  which 
works  well,  but  dries  badly  in  oil 

Lance  wood,  imported  in  long  poles 
from  3  to  6  inches  in  diameter, 
from  Cuba  and  Jamaica,  is  of  a 
paler  yellow  than  box  wood :  it  is 
selected  for  elastic  works,  as  gig 
shafts,  archery  bows  and  springs, 
surveyors'  rods,  billiard  cues,  &c. 

Landscape.  In  landscape  we  find  Na- 
ture employing  broken  colours  in 
enharmonic  consonance  and  variety, 
and  equally  true  to  picturesque  re- 
lations: she  employs  also  broken 
forms  and  figures  in  conjoint  har- 
mony with  colours,  occasionally 
throwing  into  the  composition  a 
regular  form  or  a  primary. 

Landscape  Gardening.  The  outline 
of  a  wood  may  sometimes  be  great, 
and  always  beautiful,  but  the  first 
requisite  is  irregularity.  That  a 
mixture  of  trees  and  underwood 
should  form  a  long  straight  line, 
can  never  be  natural;  and  a  suc- 
cession of  easy  sweeps  and  gentle 
rounds,  each  a  portion  of  a  greater 
or  less  circle,  composing  altogether 
a  line  literally'serpentine,  is,  if  pos- 
sible, worse ;  it  is  but  a  number  of 
regularities  put  together  in  adisor- 

251 


derly  manner,  and  equally  distant 
from  the  beautiful,  both  of  iurt  and 
of  nature. 

The  true  beauty  of  an  outline  con- 
sists more  in  breaks  than  in  sweeps ; 
tather  in  angles  than  rounds;  in 
variety,  not  in  succession.  The 
outline  of  a  wood  is  a  continued 
line,  and  small  variations  do  not 
save  it  from  the  insipidity  of  same- 
ness: one  deep  recess,  one  bold 
prominence,  has  more  effect  than 
twenty  little  irregularities;  and  that 
one  divides  the  line  into  parts,  but 
no  breach  is  thereby  made  in  its 
unity :  a  continuation  of  wood  al- 
ways remains,  the  form  of  it  only  is 
altered,  and  the  extent  increased: 
the  eye,  which  hurries  to  the  ex- 
tremity of  whatever  is  uniform,  de- 
lights to  trace  a  varied  line  through 
all  its  intricacies,  to  pause  from 
stage  to  stage,  and  so  lengthen  the 
proB;res8. 

The  parts  must  not,  however,  on 
that  account,  be  multiplied  till  they 
are  too  minute  to  be  interesting, 
and  so  numerous  as  to  create  con- 
fusion :  a  few  large  parts  should  be 
more  strongly  distinguished  in 
their  forms,  their  directions,  and 
their  situations :  each  of  these  may 
afterwards  be  decorated  with  sub- 
ordinate varieties,  and  the  mere 
growth  of  the  plants  will  occasion 
some  irregularity:  on  many  occa- 
sions more  will  not  be  required. 
Every  variety  in  the  outline  of  a 
wood  must  be  a  prominence  or  a 
recess ;  breadth  in  either  is  not  so 
important  as  length  to  the  one  and 
depth  to  the  other :  if  the  former 
ends  in  an  angle,  or  the  latter  di- 
minishes to  a  point,  they  have  more 
force  than  a  shallow  dust  or  a 
dwarf  excrescence,  how  wide  so- 
ever: they  are  greater  deviations 
from  the  continued  line  which  they 
are  intended  to  break,  and  their 
effect  is  to  enlarge  the  wood  it- 
self. 

Every  variety  of  outline  hitherto 
mentioned  may  be  traced  by  the 
underwood  alone;  but  frequents 


LAN 


LANDSCAPE  PAINTING. 


LAT 


the  same  effects  may  be  produced 
with  more  easCi  and  much  more 
heamtf,  by  a  few  trees  standing  out 
from  the  thicket,  and  belonging  or 
seeming  to  belong  to  the  wood,  so 
as  to  make  a  part  of  its  figure. 

The  materials  of  natural  land- 
scape are  ground,  wood,  and  water, 
to  which  man  adds  buildings,  and 
adapts  them  to  the  scene :  it  is 
therefore  from  the  artificial  con- 
siderations of  utility,  conTcnience, 
and  propriety,  that  a  place  derives 
its  real  value  in  the  eyes  of  a  man 
of  taste:  he  will  discover  graces 
and  defects  in  every  situation ;  he 
will  be  as  much  delighted  with  a 
bed  of  flowers  as  with  a  forest 
thicket,  and  he  will  be  as  much 
disgusted  by  the  fanciful  affecta- 
tion of  rude  nature  in  tame  scenery 
as  by  the  trimness  of  spruce  art  in 
that  which  is  wild. 

Landscape  Painting,  The  best  paint- 
ers in  landscape  have  studied  in 
Italy  or  France,  where  the  verdure 
of  England  is  unknown:  hence 
arises  the  habit  acquired  by  the 
connoisseur,  of  admiring  the  brown 
tints  and  arid  foregrounds  in  the 
pictures  of  Claude  and  Poussin;  and 
from  this  cause  he  prefers  the 
bistre  sketches  to  the  green  paint- 
ings of  Gainsborough.  One  of  our 
best  landscape  painters  studied  in 
Ireland,  where  the  soil  is  not  so 
yellow  as  in  England ;  and  his  pic- 
tures, however  beautiful  in  design 
and  composition,  are  always  cold 
and  chalky.  Autumn  is  the  fa- 
vourite  season  of  study  for  land- 
scape painters,  when  all  nature 
verges  towards  decay,  when  the 
foliage  changes  its  vivid  green  to 
brown  and  orange,  and  the  lawns 
put  on  their  russet  hue :  but  the 
tints  and  verdant  colouring  of 
spring  and  summer  will  have  su- 
perior charms  to  those  who  de- 
light in  the  perfection  of  nature, 
without  perhaps  ever  considering 
whether  they  are  adapted  to  the 
painter's  landscape. 

Limd  Steward.   A  person  solely  occu- 

252 


pied  in  the  management  and  culti- 
vation of  an  estate  should  see  to 
the  production,  advancement,  and 
value  of  the  land ;  should  be  well 
acquainted  with  the  pursuits  and 
interests  of  country  life ;  should  un- 
derstand the  qualities  of  the  soil 
and  the  proper  manuring  of  the 
same,  as  well  as  the  different  com- 
binations of  sand,  gravel,  loam, 
day,  chalk ;  he  should  be  able  to 
show  what  stock  the  pasture  will 
maintain,  what  quantity  of  grain 
the  arable  land  will  produce,  and 
what  quantity  of  hay  may  be  ex- 
pected fit>m  the  meadows:  with 
other  requisite  knowledge  pertain- 
ing to  farming,  he  will  be  able  to 
form  a  fiedr  estimate  of  the  produce 
of  the  farm,  to  keep  accounts,  and 
ultimately  acquire  a  taste  for  the 
erection  of  farm  buildings  and  la- 
bourers' rural  cottages,  and  also  the 
arrangement  of  landscape,  flower, 
and  vegetable  gardens. 

Laniard,  in  navigation,  a  stout  piece 
of  line  or  cord  used  to  fasten  and 
secure  the  shrouds,  stays,  or  buoys 

Lantern,  in  architecture,  a  small  struc- 
ture on  the  top  of  a  dome  or  in 
similar  situations  for  the  admission 
of  light,  and  the  promotion  of  ven-. 
tilation.  It  is  generally  made  or- 
namental, and  was  much  used  in 
Gothic  and  Tudor  architecture. 

LapidarhUf  a  lapidary,  a  stone-cutter 

Lapis  kuruU,  a  mineral  which  fur- 
nishes the  valuable  pigment  called 
ultramarine 

Lapis  fydius,  a  variety  of  touch-stone; 
the  schistose  jasper  of  Brongniart, 
containing  silica,  iron,  alumina, 
and  charcoal 

Laque  Min4rale  is  a  French  ^ngment, 
a  species  of  chromic  orange.  This 
name  is  also  given  to  orange  oxide 
of  iron. 

Larboard,  in  navigation,  the  left-hand 
side  of  a  ship,  standing  with  face  to 
the  head :  now  the  word  <  Port '  is 
used 

Lardrose,  a  screen  at  the  back  of  a 
seat  behind  an  altar 

Later,  a  brick  or  tile.    Besides  the 


I 


LAT 


LATHE. 


LAY 


Greeks  and  Romans,  other  ancient 
nations  employed  brick  for  build- 
ing to  a  great  extent,  especially  the 
Babylonians  and  Egyptians. 
Lathe,  a  machine  for  turning  metals 
or  wood  by  causing  the  material  to 
revolve  upon  central  points,  and  be 
cut  by  a  tool  fixed  in  a  slide-rest, 
or  held  by  hand. 

The  lathe  is  very  ancient,  and 
seems  to  have  been  known  to  the 
Greeks  and  Romans,  but,  till  within 
the  last  half  century,  was  a  very 
rough  and  almost  powerless  ma- 
chine  compared  with  the  elegant, 
very  powerful,  and  well  constructed 
macMne  now  in  use.  It  is  used  for 
turning  either  metal  or  timber,  and 
varies  in  size  and  construction,  ac- 
cording to  the  nature  of  the  work 
required. 

The  construction  of  the  present 
lathe  is  as  follows :  a  long  frame, 
called  the  lathe-bed,  having  a  per- 
fectly planed  surface,  and  a  slot  or 
mortise  from  end  to  end,  is  fixed  at 
each  end  upon  two  short  standards, 
and  upon  one  end  of  it  a  frame, 
called  the  head-stock  or  mandril- 
frame,  is  bolted:  this  frame  carries 
the  short  shaft  or  mandril,  upon 
which  are  the  driving  pulleys.  The 
end  of  the  mandril  stands  through 
the  inner  side  of  the  frame,  and  is 
screwed  so  that  a  socket  or  centre 
chuck  may  be  fixed  on  it:  this 
chuck  acts  as  a  centre  for  the  work 
to  rest  upon,  and  has  a  projecting 
arm  orjdriver  to  carry  it  round  with 
it.  Another  frame,  called  the  back 
centre  frame,  capable  of  being  fixed 
upon  the  lathe-bed  at  any  distance 
from  the  front  centre,  has  a  cyhn- 
der,  with  a  pointed  end  or  centre, 
at  precisely  the  same  height  as  the 
other,  with  two  set-screws,  one  to 
adjust  the  centre  piece,  the  other 
to  fix  it.  The  work  is  placed  be- 
tween these  two  centres,  and  caused 
to  revolve  by  a  band  passing  over 
a  pulley  on  the  mandril,  if  the  lathe 
is  large,  and  by  a  treddle  and  band- 
wheel,  if  the  lathe  is  small. 

In  small  lathes,  the  rest,  upon 

"253 


which  the  tool  is  held,  is  fixed  in 
a  socket  cast  on  a  small  slide  by  a 
set-screw:  the  slide  is  for  adjust- 
ing its  position,  and  is  capable  of 
being  fixed  at  any  part  of  the  lathe- 
bed  between  the  centres. 

In  large  lathes  the  slide-rest  is 
always  used.    See  Slide-resi. 

Lathe-bed,  that  part  of  a  lathe  on 
which  the  '  poppet-head  *  slides 
forward  or  backward  to  its  required 
position 

Latitude,  breadth,  width,  extent ;  in 
geography,  the  distance,  north  or 
south,  from  the  equator,  a  great 
circle,  equally  distant  from  the 
poles,  dividing  the  globe  into  equal 
parts,  north  and  south 

Latten,  a  mixed  metal  resembling 
brass.  The  monumental  brasses  in 
churches  are  called  latten. 

Lattemsail,  in  navigation,  a  long 
triangular  sail  used  in  xebecs,  &c. 

Launders,  in  mining,  tubes  and  gut- 
ters for  the  conveyance  of  water  in 
mines,  &c. 

Lavatory,  a  cistern  or  trough  to  wash 
in,  used  formerly  in  monasteries 

Laver,  brazen.  Moses  was  directed 
to  make,  among  other  articles  of 
furniture,  for  the  services  of  the  ta- 
bernacle, a  laver  of  brass,  borne  by 
four  cherubim,  standing  upon  bases 
or  pedestals,  mounted  on  brazen 
wheels,  and  having  handles  belong- 
to  them,  by  means  of  which  they 
might  be  drawn  and  conveyed  frt)m 
one  place  to  another,  as  they  should 
be  wanted.  These  lavers  were 
double,  composed  of  a  basin  which 
received  the  water  that  fell  from 
another  square  vessel  above  it,  from 
which  the  water  was  drawn  by  cocks. 
The  whole  work  was  of  brass :  the 
square  vessel  was  adorned  with  the 
heads  of  a  lion,  an  ox,  and  a  che- 
rub. Each  of  the  lavers  contained 
forty  baths,  or  four  bushels,  forty, 
one  pints,  and  forty  cubic  inches  of 
Paris  measure. 

Lay  figure,  a  figure  made  of  wood 
or  cork,  in  imitation  of  the  human 
body.  It  can  be  placed  in  any  po- 
sition or  attitude,  and  moves  at 


LAZ 


LEVELLING. 


LEV 


every  joint,  on  the  principle  of  the 
ball  and  socket.  It  serves,  when 
clothed,  as  a  model  for  drapery 
and  for  fore-shortening.  The  dress 
of  the  person  is  generally  placed  on 
the  lay-figure  after  the  head  is 
taken,  by  which  the  painter  finishes 
his  entire  portrait  at  leisure,  with- 
out  requiring  the  person  to  sit. 

Lazaretto,  an  hospital  ship  for  the 
reception  of  the  sick 

Lead  is  a  very  heavy  metal,  suffici- 
ently well  known.  The  mode  of 
pur^yiiig  it  from  the  dross  which 
is  mixed  with  it,  by  subjecting  it  to 
a  fierce  flame,  and  melting  off  its 
scoria,  furnishes  several  dlusions 
in  Scripture  to  God's  purifying  or 
punishing  his  people.  It  was  one 
of  the  substances  used  for  writing 
upon  by  the  ancients 

Leader,  a  branch,  rib,  or  string  of  ore, 
leading  along  to  the  lode 

Lead  spar,  sulphate  of  lead 

Leading  springs,  the  springs  fixed 
upon  the  leading  axle-box  of  a  lo- 
comotive engine,  bearing  the  weight 
above 

Leading  wheels,  the  wheels  of  a  loco- 
motive engine,  which  are  placed 
before  the  driving  wheels 

Leat,  a  water-course,  or  level  for 
conveyance  of  water 

Leaves,  a  term  applied  to  vrindow- 
shutters,  the  fol^ng-doors  of  clo- 
sets, &c. 

Leaving  (in  Cornish),  or  casualties, 
in  tin,  is  the  same  as  hanaways  of 
copper  or  lead  ore 

Lectern  or  Lettem,  the  desk  or  stand 
on  which  the  larger  books  used  in 
the  services  of  the  Roman  Catholic 
church  are  placed.  In  modem 
Protestant  churches  they  are  now 
often  used,  and  are  very  ornamental 
in  appearance,  and  far  more  ap- 
propriate than  the  cumbersome 
reading-desk.  Lecterns  are  made 
sometimes  of  stone  or  marble,  but 
usually  of  wood  and  brass,  and 
generally  are  extremely  well  exe- 
cuted. 

Lectus,  a  bed  or  couch 

Ledger,  a  large  fiat  stone  laid  over  a 

254 


tomb :  horizontal  timbers  used  in 
forming  scaffolding  are  also  called 
ledgers 

Ledgment,  a  string-course,  or  hori- 
zontal suite  of  mouldings,  such  as 
the  base-mouldings  of  a  building 

Lee,  in  navigation,  the  side  opposite 
to  the  wind;  as  the  lee-shore  is 
that  on  which  the  wind  blows 

Lembus,  according  to  Plautus,  a  skiff 
or  small  boat,  used  for  carrying  a 
person  from  a  ship  to  the  shore 

Lemon  yellow,  a  beautiful  light  and 
vivid  colour.  In  body  and  opacity 
it  is  nearly  equal  to  Naples  yellow 
and  masticot,  but  much  more  pure 
and  lucid  in  colour  and  tint,  and  at 
the  same  time  not  liable  to  change 
by  damp,  sulphurous  or  impure  air, 
or  by  the  action  of  light,  or  by  the 
steel  palette-knife,  or  by  mixture 
of  white  lead  or  other  pigments, 
either  in  water  or  oil. 

Levecel,  anciently  a  pent-house,  or  a 
projecting  roof  over  a  window, 
door,  &c. 

Level,  an  instrument  for  determining 
the  heights  of  one  place  vrith  re- 
spect to  another 

Levelling,  the  art  by  which  the  rela- 
tive heights  of  any  number  of 
points  are  determined. 

The  height  of  a  point  is  the 
vertical  distance  to  which  it  is  ele- 
vated or  depressed,  as  compared 
with  the  true  general  surface  of 
the  earth. 

The  earth  is  in  form  a  spheroid. 
On  land  we  can  nowhere  trace  its 
true  geometric  surface ;  but  the 
sea,  when  at  rest,  presents  every 
where  a  very  near  approximation 
to  it,  and  hence  the  level  of  the 
sea  has  been  assumed  as  the  stand- 
ard to  which  all  heights  are  to  be 
referred. 

The  absolute  height,  then,  of  any 
point  is  its  vertical  distance  from 
the  level  of  the  sea:  the  relative 
height  of  two  or  more  points,  com- 
monly called  then:  difference  of 
level,  is  the  difference  of  those  ver- 
tical  distances. 
A  true  level  is  any  surface  or 


LEV 


LIGHT. 


LIG 


line  which  is  parallel  to  the  true 
geometric  surface  of  the  earth; 
every  true  level  must,  therefore, 
necessarily  present  a  curve  every 
vrhere  perpendicular  to  the  direc- 
tion of  gravity.  It  is  a  heautifiil 
property  of  fluids  that  in  every 
situation,  when  at  rest,  their  sur- 
face  will  present  a  true  level. 

All  points  situated  within  the 
same  true  level  are  evidently  at  the 
same  height. 

One  point  is  said  to  he  higher  or 
lower  than  another,  according  as  a 
true  level  traced  through  it  passes 
ahove  or  below  that  point ;  and 
the  vertical  distance  at  which  it  so 
passes  is  the  measure  of  its  relative 
height. 

In  theory,  levelling  is  extremely 
simple.  It  consists  in  tracing 
through  space  a  series  of  level  sur- 
faces, and  finding  their  intersec- 
tions with  vertical  lines  passing 
through  the  points  whose  relative 
height  we  wish  to  ascertain. 
Levels  Road,&  triangular  frame  of  wood 
with  a  long  straight  base,  and  a 
plummet  suspended  by  a  thread 
from  the  vertex  of  the  triangle. 
When  the  ground  to  which  it  is 
applied  is  level,  the  thread  will  co- 
incide with  a  line  perpendicular  to 
the  base. 

A  tool  similar  in  principle  to  the 
above-mentioned  is  used  by  fitters, 
and  is  made  of  a  plate  of  sheet- 
iron,  two  sides  of  which  form  a 
right  angle,  and  the  thread  which 
suspends  the  plummet  is  parallel  to 
the  vertical  side  when  the  base  is 
level. 
Levelf  Spirit,  a  glass  tube,  closed  at 
the  ends,  and  nearly  filled  with 
water  or  spirits,  fixed  in  a  piece  of 
wood  or  metal,  with  a  flat  base,  to 
which  the  tube  is  perfectly  parallel. 
When  placed  upon  a  level  surface, 
an  air-bubble  will  be  at  the  centre 
of  the  tube. 
LeteTf  the  first  mechanical  power, 
being  an  inflexible  straight  bar, 
supported  in  a  single  point  on  a 
fulcrum  or  prop,  called  its  centre 


of  motion :  it  is  used  to  elevate  a 
great  weight 

Lever-vahej  a  safety-valve  kept  in  its 
seat  by  the  pressure  of  a  lever  with 
an  adjustable  weight.  In  locomo- 
tive engines  a  spring  is  used  at  the 
end  of  the  lever,  instead  of  the 
weight ;  and  the  pressure  is  regu- 
lated by  a  screw,  and  indicates  on 
a  brass  plate. 

Levigatiofif  the  process  of  reducing 
hard  bodies  into  subtile  powder  by 
grinding  upon  marble  with  a  muller 

LewiSf  an  instrument  used  by  masons 
for  hoisting,  consisting  of  thin 
wedges  of  iron,  forming  a  dovetail, 
which  is  indented  into  a  large  stone 
for  the  purpose  of  moving  it 

Lei/f  a  standard  of  metal;  contents  in 
pure  metal ' 

Lihellay  a  small  balance ;  a  level  used 
by  carpenters  and  masons,  to  test 
flat  surfaces 

Libra,  a  pound  weight;  a  balance,  or 
a  pair  of  scales :  one  of  the  twelve 
signs  of  the  zodiac 

Library,  a  room  or  rooms  appropri- 
ated for  the  arrangement  and  keep- 
ing of  books,  fitted  up  with  shelves 
to  hold  them,  or  furniture  called 
book-cases,  to  which  shelves  are  af- 
fixed for  the  same  purpose 

Lifts,  in  navigation,  the  ropes  at  the 
yard-arms,  used  to  make  the  yards 
hang  higher  or  lower,  as  required 

Lifting-gear,  the  apparatus  for  Ufting 
the  safety-valves  from  within  a 
boiler :  it  consists  of  levers  con- 
nected to  the  valve  and  to  a  screw 
workedby  ahandle  outsidethe  boiler 

Light,  The  meteorological  pheno- 
mena induced  by  the  action  of  light 
are,  chiefiy,  atmospheric  refraction, 
i.e.  the  temperature  of  the  different 
strata  of  the  atmosphere ;  the  tints 
which  at  certain  times  spread  over 
the  disc  of  the  sun,  the  moon,  and 
the  stars;  the  various  aspects  of 
the  waters  of  the  ocean,  of  seas, 
and  of  lakes;  the  Fata  Morgana, 
the  mirage,  and  all  those  varied 
optical  appearances  which  both 
celestial  and  terrestrial  objects  pre- 
sent when  seen  through  atmosphe- 


255 


LI6 


LIMESTONE. 


LIM 


ric  strata  of  different  degrees  of 
elasticity. 

lAght  red  is  an  ochre  of  a  russet- 
orange  hue ;  principally  valued  for 
its  tints.  The  common  light  red 
is  brown  ochre  burnt;  but  the  prin- 
cipal yellow  ochres  afford  this 
colour  best ;  and  the  brighter  and 
better  the  yellow  from  which  this 
pigment  is  prepared,  the  brighter 
will  this  red  be,  and  the  better 
flesh-tints  will  it  afford  with  white. 

Ligrmm  vitiBt  or  Guatacunif  is  a  very 
hard  and  heavy  wood,  shipped  from 
Cuba  and  other  adjacent  islands. 
When  first  cut,  it  is  soft  and  easily 
worked;  but  it  speedily  becomes 
much  harder  on  exposure  to  the 
air.  It  is  cross-grained,  covered 
with  a  smooth  yellow  sap,  Uke  box, 
almost  as  hard  as  the  wood,  which 
is  of  a  dull  brownish  green,  and 
contains  a  large  quantity  of  the 
gum  guaiacum,  which  is  extracted 
for  the  purposes  of  medicine.  The 
wood  is  used  in  machinery,  and  for 
rollers,  presses,  mills,  pestles  and 
mortars,  sheaves  for  ships'  blocks, 
skittle-balls,  &c. 

Limber  boards^  short  pieces  of  plank 
fitted  from  the  limber  strake  to  the 
keelson  of  a  ship,  butting  at  the 
sides  of  all  the  bulk-heads,  that 
they  may  be  easily  taken  up 

Limber  straket  the  strake  of  wood 
waleing  nearest  the  keelson,  from 
the  upper  side  of  which  the  depth 
in  the  hold  of  a  vessel  is  measured 

Lime  or  Quicklime.  When  required 
perfectly  pure,  lime  is  obtained  by 
heating  to  whiteness,  in  an  open 
platinum  crucible,  precipitated  car- 
bonate :  most  marbles  yield  it  mo- 
derately pure ;  but  as  prepared  for 
ordinary  purposes,  by  the  calcina- 
tion of  common  limestone  in  a  fur- 
nace  with  coal,  it  is  far  otherwise 

Limestone  becomes  lime  on  being  de- 
prived of  its  carbonic  acid  and  of 
the  water  it  contains,  whether  hy- 
grometrically  or  in  combination. 
The  agent  employed  to  effect  this 
is  heat. 
With  the  same  heat,  the  cald- 

256^ 


nation  is  effected  with  more  ease 
and  rapidity,  in  proportion  as  the 
stone  is  of  a  less  compact  texture 
than  the  smallness  in  bulk  of  the 
fragments  into  which  it  is  reduced, 
or  to  its  being  impregnated  with 
a  certain  degree  of  humidity. 

The  contact  of  the  air  is  not  in- 
dispensable, but  it  exercises  a  useful 
influence,  especially  in  regard  to 
argillaceous  limestone.  Moreover, 
no  limestone  can  be  converted  into 
lime  in  a  vessel  so  close  as  to  ren- 
der the  escape  of  the  carbonic  acid 
impossible. 

Limestone  which  is  pure,  or 
nearly  so,  supports  a  white  heat 
without  inconvenience.  Under  the 
intense  heat  of  the  hydro-oxygen 
blow-pipe  this  substance  affords  the 
brilliant  light,  the  beautiful  appli- 
cation of  which  to  the  microscope 
is  now  so  well  known.  The  com- 
pound limestone,  on  the  other  hand, 
alloyed  in  the  proportions  necessary 
to  form  hydraulic  or  eminently 
hydraulic  lime,  fuses  easily.  Its 
calcination  demands  certain  pre- 
cautions :  the  heat  ought  never  to 
be  pushed  beyond  the  common  red 
heat,  the  intensity  being  made  up 
for  by  its  duration. 

The  compound  limestone,  when 
too  much  burnt,  is  heavy,  compact, 
dark-coloured,  covered  with  a  kind 
of  enamel,  especially  about  the  an- 
gular parts;  it  slakes  M'ith  great 
difiSculty,  and  gives  a  lime  carbon- 
ized and  without  energy:  some- 
times it  will  not  slake  at  all,  but 
becomes  reduced,  after  some  days- 
exposure  to  the  air,  to  a  harsh 
powder  altogether  inert. 

The  pure  and  compound  lime- 
stones, when  insufiiciently  burnt, 
either  refuse  to  slake,  or  slake  only 
partially,  leaving  a  solid  kernel,  a 
kind  of  sub-carbonate  virith  excess 
of  base. 

The  calcining  of  calcareous  mi- 
nerals constitutes  the  art  of  the 
lime-burner.  According  to  situa- 
tion, either  fire-wood,  fagots,  brush- 
wood, turf,  or  coal  is  used. 


LIM 


LIMESTONE. 


LIM 


Lime-kilns  of  various  kinds  have 
have  been  suggested  or  tried.  The 
forms  of  interior  most  generally 
adopted  are,  Ist,  the  upright  rect- 
angular prism;  2nd,  the  cylin- 
der ;  3rd,  the  cylinder  surmounted 
by  an  erect  cone  slightly  trun- 
cated; 4th,  a  truncated  inverted 
cone;  5th,  an  ellipsoid  of  revo- 
lution variously  curvated,  or  egg- 
shaped  kiln. 

The  rectangular  kilns  are  in  use 
in  Nivernais,  and  in  the  south  of 
France,  in  which  are  burnt,  at  the 
same  time,  limestone  and  bricks. 
The  limestone  occupies  very  nearly 
the  lower  half  of  the  capacity.  The 
upper  is  filled  with  bricks,  or  tiles, 
Itud  and  packed  edgewise. 

The  cylindric  kUns  are  princi- 
pally employed  upon  works  which 
consume  a  large  quantity  of  lime  in 
a  short  time.  They  are  termed 
'field-kilns;'  their  construction  is 
expeditious  and  economical,  but 
precarious.  Above  a  pointed  oven- 
shaped  vault,  is  raised,  in  the  form 
of  a  tower,  a  high  stack  of  lime- 
stone, which  is  enclosed  by  a  cur- 
tain of  rammed  earth,  and  supported 
outwardly  by  a  coarse  wattlhig,  in 
which  care  is  taken  to  leave  an 
opening  to  introduce  the  fire  be- 
neath the  vault. 

The  kilns  of  the  third  kind  are 
constructed  in  a  solid  and  durable 
manner,  like  the  four-sided  kilns : 
no  bricks  are  burnt  in  these ;  the 
largest  stones  occupy  the  lower  part 
of  the  cylinder ;  the  smaller  pieces 
and  fragments  are  thrown  into  the 
cone  which  surmounts  it. 

The  kilns  of  the  fourth  and  fifth 
kind  are  specially  intended  for  the 
burning  with  coaL 

The  interior  wall  of  the  kiln  is 
generally  built  with  bricks,  or  other 
material  unalterable  by  heat,  ce- 
mented throughout  a  thickness  of 
from  12  to  15  inches  with  a  mix- 
ture of  sand  and  refractory  clay, 
beaten  together. 

In  the  flare-kilns  fed  by  logs  or 
brush-wood,tlie  charge  always  rests 

257 


upon  one  or  two  vaults  built  up 
dry  with  the  materials  of  the  charge 
itself.  Underneath  these  vaults 
a  small  fire  is  lighted,  which  is 
gradually  increased  as  they  retire, 
in  proportion  as  the  draught  esta- 
blishes itself,  and  gains  force.  On 
reaching  the  exterior,  the  aperture 
at  the  eye  of  the  kiln  is  suitably 
adjusted,  and  then  kept  constantly 
filled  with  the  combustible.  The 
air  which  rushes  in  carries  the  flame 
to  a  distance  over  every  point  of  the 
vaults:  it  insinuates  itself  by  the 
joints,  and  is  not  long  in  extending 
the  incandescence  by  degrees  to  the 
highest  parts. 

There  are  some  kinds  of  stone 
which  the  fire,  however  well  re- 
gulated, seizes  suddenly,  and  causes 
to  fiy  with  detonation:  they  can- 
not, without  the  risk  of  spoiling 
the  charge,  be  used  for  the  con- 
struction of  the  vaults  and  piers  in 
loading  the  kiln.  In  such  a  case, 
materials  which  are  free  from  this 
inconvenience  are  employed. 

Practice  can  alone  indicate  the 
time  proper  for  the  calcination.  It 
varies  with  a  multitude  of  circum- 
stances, such  as  the  more  or  less 
green,  more  or  less  dry  quality  of 
the  wood;  the  direction  of  the 
wind,  if  it  favour  the  draught,  or 
otherwise,  &c.  The  master-bumers 
usually  judge  by  the  general  settling 
of  the  charge,  which  varies  from 
^  to  ^.  In  a  kiln  of  the  capacity 
of  from  211-8  to  264*75  cubic  feet, 
the  fire  lasts  from  100  to  150  hours. 
In  the  coal-kilns  by  slow  heat, 
the  stone  and  coal  are  mixed.  Of 
all  the  methods  of  burning  lime, 
this  is  certainly  the  most  precarious 
and  difficult ;  more  especially  when 
applied  to  the  argillaceous  lime- 
stone. A  mere  change  in  the  du- 
ration or  intensity  of  the  wind,  any 
dilapidation  of  the  interior  wall  of 
the  kiln,  a  too  great  inequality  in 
the  size  of  the  fragments,  are  so 
many  causes  which  may  retard  or 
accelerate  the  draught,  and  occasion 
irregular  movements  in  the  descent 


LIM 


LIMES,  HYDRAULIC. 


LIM 


of  the  materials,  which  become 
locked  together,  form  a  vault,  and 
precipitate  at  ooe  time  the  coal,  and 
another  the  stone,  upon  the  same 
point:  hence  an  excess  oi^defidency 
in  the  calcination. 

Sometimes  a  kiln  works  perfectly 
veil  for  many  weeks,  and  then  aU 
at  once  gets  out  of  order  without 
any  visible  cause.  A  mere  change 
in  the  quality  of  the  coal  is  s^- 
ficient  to  lead  the  most  experienced 
lime-burner  into  error.  In  a  word, 
the  calcination  by  means  of  coal, 
and  the  slow  heat,  is  an  affair  of 
cautious  investigation  and  prac- 
tice. 

The  capacity  of  a  furnace  con- 
tributes, no  less  than  does  its  form, 
'  to  an  equable  and  proper  calcina- 
tion. There  are  limits  beyond 
which  they  cannot  be  enlarged 
without  serious  evUs. 

The  bulk  of  coal  burnt  to  pro- 
duce a  cubic  foot  of  lime  neces- 
sarily varies  with  the  hardness  of 
the  limestone  used,  but  ¥dthin 
narrow  limits. 

The  calcination  of  limestones 
presents  other  important  problems, 
which  can  only  be  solved  by  expe- 
riment. 
lAmeSt  hydraulic  (artificial).  Already 
the  artificial  limes  have  been  ap- 
plied to  a  number  of  important 
works.  In  the  canals  of,Saint  Martin 
and  Saint  Maur  they  have  almost 
exclusively  been  used.  Nearly  a 
thousand  cubic  metres  have  been 
employed  within  five  years  at  the 
harbour  of  Toulon.  These  limes 
have  served  for  the  fabrication  of 
the  mortar  for  the  foundations  of 
several  bridges,  and  |their  con- 
sumption is  increasing  daily  in 
Paris  and  its  environs. 

The  artificial  hydraulic  limes  are 
prepared  by  two  methods :  the  most 
perfect,  but  also  the  most  expen- 
sive, consists  in  mixing  with  rich 
lime,  slaked  in  any  way,  a  certain 
proportion  of  clay,  and  calcining 
the  mixture :  this  is  termed  '  arti- 
ficial lime  twice  kilned: 


By  the  second  process,  any  very 
soft  calcareous  substance  is  sub- 
stituted for  the  lime  (such,  for  ex- 
ample, as  chalk,  or  the  tufas),  which 
it  is  easy  to  bruise  and  reduce  to  a 
paste  with  water.  From  this  a 
great  saving  is  derived,  but  at  the 
same  time  an  artificial  lime,  perhaps 
of  not  quite  so  excellent  a  quality 
as  by  the  first  process,  in  conse- 
quence of  the  rather  less  perfect 
amalgamation  of  the  mixture.  In 
fact,  it  is  impossible,  by  mere  me- 
chanical agency,  to  reduce  calca- 
reous substances  to  the  same  degree 
of  fineness  as  slaked  lime.  Never- 
theless, this  second  process  is  the 
more  generally  followed,  and  the 
results  to  which  it  leads  become 
more  and  more  satisfactory. 

By  a  proper  regulation  of  the 
proportions,  a  degree  of  energy 
may  be  given  to  the  factitious  lime, 
which  wiU  render  equal  it  if  not 
superior  to  the  natural  hydraulic 
limes. 

It  is  usual  to  take  twenty  parts  of 
dry  clay  to  eighty  parts  of  very 
rich  lime,  or  to  one  hundred  and 
forty  of  carbonateof  lime.  But  if  the 
lime  or  its  carbonate  should  already 
be  at  all  mixed  in  the  natural  state, 
then  fifteen  parts  of  clay  will  be 
sufllcient.  Moreover,  it  is  proper 
to  determine  the  proportions  for 
every  locality.  In  fact,  all  clays 
do  not  resemble  one  another  to  such 
an  extent  as  to  admit  of  their 
being  considered  as  identical:  the 
finest  and  softest  are  the  best. 

There  is  at  Meudon,  near  Paris, 
a  manufactory  of  artificial  lime,  set 
on  foot  by  Messrs.  Brian  and  ^^' 
Leger.  The  materials  made  use  of 
are,  the  chalk  of  the  countiy  and 
the  clay  of  Vaugirard,  which  is 
previously  broken  up  into  lumps  of 
a  moderate  size.  A  millstone  set 
up  edgewise,  and  a  strong  wheel 
with  spokes  and  felloes,  firmly  at- 
tached to  a  set  of  harrows  and  rakes, 
are  set  in  movement  by  a  two- 
horse  gin,  in  a  circular  basin  of 
about  six  feet  and  a  half  radius. 


258 


LIM 


LINK  MOTION. 


LIN 


In  the  middle  of  the  basin  is  a 
pillar  of  masonry,  on  which  turns 
the  vertical  arbor  to  which  the 
whole  system  is  fixed:  into  this 
basin,  to  which  water  is  conveyed 
by  means  of  a  cock,  foar  measures 
of  chalk  are  successively  thrown, 
and  one  measure  of  clay.  After  an 
hour  and  a  half's  working,  about 
fifty-three  cubic  feet  (English)  of  a 
thin  pulp  is  obtained,  whichis  drawn 
off  by  means  of  a  conduit,  pierced 
horizontally  on  a  level  with  the  bot- 
tom of  the  basin. 

The  fluid  descends  by  its  own 
weight;  first  into  one  excavation, 
then  into  a  second,  then  a  third, 
and  so  on  to  a  fourth  or  fifth. 
These  excavations  communicate 
with  one  another  at  top.  When 
the  first  is  full,  the  fresh  liquid,  as 
it  arrives,  as  well  as  the  super- 
natant fluids,  flow  over  into  the 
second  excavation ;  from  the  second 
into  the  third,  and  so  on  to  the 
last,  the  clear  water  from  which 
drahis  ofiTinto  a  cesspool.  Other 
excavations,  cut  in  steps  like  the 
preceding,  serve  to  receive  the 
fresh  products  of  the  work,  whilst 
the  material  in  the  first  series  ac- 
quires the  consistency  necessary 
for  moulding.  The  smaller  the 
depth  of  the  pans  in  relation  to 
their  superficies,  the  sooner  is  the 
above-mentioned  consistency  ob- 
tained. 

The  mass  is  now  subdivided  into 

solids  of  a  regular  form  by  means 

of  a  mould.      This  operation  is 

executed  with  rapidity.  A  moulder, 

working  by  the  piece,  makes  on  an 

average  five  thousand  prisms  a  day, 

which  will  measure  211*8  cubic 

feet.    These  prisms  are  arranged 

on  drying  shelves,  where  in  a  short 

lime  they  acquire  the  degree  of 

desiccation  andhardness  proper  for 

caldnation.    At  Paris  a  mixture  of 

coke  and  coal  is  employed,  and 

the  common  mode  of  burning  by 

slow  heat  rendered  necessary  by  that 

kind  of  combustible. 

The  artificial  hydraulic  limes  are 

259     ~~~~ 


intended  to  supply  the  place  of  the 
natural  ones  in  those  countries 
where  the  argillaceous  hmestone 
is  entirely  wanting,  and  which  are 
commonly  sold  in  Paris. 

Lime-tree  (the)  is  common  in  Europe, 
attains  considerable  size,  is  very 
light-coloured,  fine  and  close  in 
the  grain,  and  is  used  in  the  con- 
struction of  piano-forteSfharps,  &c.t 
it  is  particularly  suitable  for  carving, 
from  its  even  texture  and  freedom 
from  knots.  The  works  of  Gibbons 
at  Windsor  Castle,  and  St.  Paul's, 
London,  are  of  the  Ume-tree. 

Limninfft  a  term  formerly  applied  to 
portrait  -  painting,  is  drawing  or 
painting  the  body  and  limbs  of  the 
human  figure 

Linch'pin,  the  small  pin  in  carts,  &c., 
that  is  put  at  the  ends  of  the  axle- 
tree  to  confine  the  wheels  on  them 
steadily 

Linear  perspective  is  that  which  de- 
scribes or  represents  the  position, 
magnitude,  form,  &c.  of  the  se- 
veral lines  or  contours  of  objects, 
and  expresses  their  diminution,  in 
proportion  to  their  distance  from 
the  eye 

Lbuk'tnotion,  a  new  apparatus  for  re- 
versing steam  engines :  it  is  used  in 
locomotive  engines  instead  of  the 
reversing  forks,  and  consists  of  a 
link  with  a  slot  from  end  to  end, 
into  which  a  guide-block  fits,  and 
is  connected  to  the  slide-valve  rod : 
the  rods  of  the  two  eccentrics  are 
connected  one  to  each  end  of  the 
link,  which  is  raised  or  lowered,  or 
held  in  a  central  position  by  appa- 
ratus attached  to  the  centre  of  it, 
moved  by  the  reversing  lever. 
When  the  link  is  in  a  central  po- 
sition with  regard  to  the  slide- 
valve  rod,  the  guide-block  remains 
stationary,  as  it  is  then  at  thie  centre 
upon  which  the  link  vibrates.  When 
the  link  is  up,  the  guide-block  is  at 
the  lower  end,  and  the  slide  receives 
motion  from  the  backward  eccen- 
tric. When  the  link  is  dovm,  it 
receives  motion  from  the  forward 
eccentric. 


LIN 


LOCKS  FOR  CANALS. 


LOG 


UnkSf  in  locomotiYe  engines,  are  fiat 
or  round  pieces  of  iron  with  round 
holes  at  each  end:  they  are  used 
to  connect  together,  by  bolts,  dif- 
ferent parts  of  the  mechanism  of 
the  engine 

Lintelf  a  piece  of  timber  or  stone 
placed  horizontally  over  a  door- 
way  or  window,  to  support  the 
superincumbent  weight 

Lintel,  **  And  ye  shall  take  a  bunch 
of  hyssop,  and  dip  it  in  the  blood 
that  is  in  the  basin,  and  strike  the 
lintel  and  the  two  side-posts  with 
the  blood  that  is  in  the  basin ;  and 
none  of  you  shall  go  out  at  the 
door  of  his  house  until  the  morn- 
ing."— Exodus  xii.  22. 

lAquid  mbiatCt  or  Liquid  madder  lake, 
is  a  concentrated  tincture  of  mad- 
der, of  the  most  beautiful  and  per- 
fect rose  colour  and  transparency. 
It  is  used  as  a  water  colour  only  in 
its  simple  state,  diluted  with  pure 
water,  with  or  without  gum;  it 
dries  in  oil,  by  acting  as  a  dryer 
to  it.  Mixed  or  ground  with  all 
other  madder  colours,  with  or  with- 
out gum,  it  forms  combinations 
which  work  freely  in  simple  water, 
and  produce  the  most  beautiful  and 
permanent  effects. 

lAtJiographyt  the  art  of  drawing  on 
and  engraving  on  stone,  and  taking 
impressions  from  the  same  at  press, 
siinilarly  to  copper-plate  printing, 
but  differing  in  manipulation 

lAttle  windSf  in  mining,  an  under- 
ground shaft,  sunk  from  the  hori- 
zontal  drift,  by  which  the  top  of 
the  winds  communicates  with  the 
side  or  bottom  of  the  great  work- 
ing-shaft 

Load  water-line,  the  mark  on  a  ship 
which  the  water  makes  when  she 
is  loaded 

Loam,  a  natural  mixture  of  sand  and 
clay:  in  the  neighbourhood  of 
London,  loam  consists  of  fine  red- 
dish-gray sand  87  parts,  allumina 
13  parts  «  100 

Local  colours  are  such  as  faithfully 
imitate  those  of  a  particular  object, 
or  such  as  are  natural  and  proper 

260  ~" 


for  each  particular  object  in  a  pic- 
ture; and  colour  is  distinguished 
by  the  term  trial,  because  the  place 
it  fills  requires  that  particular  co- 
lour, in  order  to  give  a  greater 
character  of  truth  to  the  several 
colours  around  it 

LocJk,  a  mechanical  contrivance  to 
fasten  a  door,  gate,  or  any  place  or 
thing  for  security.  A  vast  deal  of 
ingenuity  has  been  exercised  to 
prevent  false  openings :  keys  of  va- 
rious kinds  are  made  to  fit  the 
wards  (interior  contrivances),  and 
prevent  what  is  called  picking,  the 
key  being  made  only  to  suit  that 
belonging  to  the  possessor. 

Lock,  in  inland  navigation,  a  portion 
of  a  canal  confined  between  a  sluice- 
gate and  a  flood-gate,  to  facilitate 
the  passage  of  boats  in  ascending 
or  descending  planes 

Lockrand,  a  course  of  bond  stones,  or 
a  bonding  course,  in  masonry 

Locks  for  canal  and  river  navigation. 
The  earliest  approximation  to  what 
is  now  known  by  the  name  of  lock 
consisted  of  a  simple  dam  formed 
across  the  bed  of  a  river,  so  as  to 
raise  the  water  \o  such  a  height  as 
to  allow  vessels  to  float  along  it. 
Where  the  river  had  a  considerable 
fall  with  a  strong  current,  it  was 
necessary  to  have  these  dams  at 
short  distances  from  each  other, 
otherwise  the  requisite  depth  of 
water  could  not  be  obtained.  As 
the  whole  space  between  two  of 
these  dams  was  in  fact  the  lock, 
it  was  necessaiy,  in  passing  from 
one  level  to  another,  to  run  down 
the  water  for  the  whole  of  that 
distance,  thereby  causing  consider- 
able delay,  and  a  waste  of  water 
that  would  now  be  considered  a 
serious  evil.  In  China  these  danis 
are  common,  and  they  have  also 
been  used  on  the  Continent. 

Lock  with  a  double  set  of  gates,  but 
no  chamber  walls,  are  now  of  ordi- 
nary construction.  The  evils  at- 
tendant  on  the  dams  formerly 
constructed  were  in  a  great  mea- 
sure removed  by  the  introduction 


LOG 


LOCKS  WITH  SIDE  PONDS. 


LOG 


of  double  sets  of  gates  or  sluices ; 
the  upper  set  being  constructed  so 
near  to  the  lower  as  only  to  leave 
room  enough  for  the  vessel  or  ves- 
sels to  float  between  them.  Framed 
gates  were  also  used  instead  of  se- 
parate beams  and  planks,  because 
the  space  to  be  emptied  or  filled 
was  so  small  that  a  very  short  time 
was  required  to  pass  the  water, 
and  there  was  no  stream  of  suffi- 
cient   strength   to   prevent   their 
being  easily  opened.    Where  these 
locks  are  intended  for  rivers,  it  is 
usual  to  make  a  side  cut  or  arti- 
ficial canal  for  the  purposes  of  the 
navigation,  and  to  leave  the  river 
course  for  the  passage  of  the  sur- 
plus water.    A  quick  bend  of  the 
river  is  generally  chosen  for  one  of 
these  cuts;  and  to  keep  the  water 
in  the  upper  part  of  the  river  to  a 
sufficient  height  for  navigation,  a 
dam  or  weir  is  made  across  the  old 
river  course  at  or  below  the  point 
where  the  artificial  cut  quits  it. 
The  lock  is  then  built  at  the  most 
convenient  part  of  the  cut,  and  its 
fall  made  equal  to  the  difference  in 
the  levels  of  the  water  at  the  top 
and  at  the  bottom  of  the  dam  'or 
weir.     When  a  vessel  is  going  up 
the  river,  she  floats  along  the  cut, 
and  passes  between  the  lower  gates 
into  the  lock ;  the  lower  gates  are 
then   closed,    and  the  valves    or 
paddles  of  the  upper  gates  being 
opened,  the  water  flows  into  the 
lock,  and  rises  to  the  level  of  the 
upper  part  of  the  river ;  the  upper 
gates  are  then  opened,  and  the 
vessel  floats  out  of  the  lock.    The 
reverse  of  this  operation  conducts 
a  vessel  down  the  river. 

The  abutments  for  the  gates  have 
been  made  of  timber,  brick-work, 
and  masonry ;  but  when  the  double 
set  of  gates  was  first  introduced,  it 
was  usual  to  leave  the  space  be- 
tween the  upper  and  lower  gates 
unprotected  by  either  timber  or 
any  kind  of  building.  Of  course 
the  agitation  of  the  water  in  the 
lock  was  constantly  washing  away 

261 


the  earthen  banks,  thereby  causing 
a  risk  of  their  being  broken  down 
by  such  continued  weakening ;  and 
by  enlarging  the  space  between  the 
two  sets  of  gates,  it  occasioned  a 
loss  of  time  in  emptying  and  filling, 
as  well  as  a  waste  of  water. 

lA>ck  {common  modem  canal), — The 
difference  of  altitude  between  the 
upper  and  lower  levels,  where  the 
locks  are  constructed,  varies  ac- 
cording to  local  circumstances. 
Where  the  ground  is  longitudinally 
steep  and  water  plentiful,  the  locks 
are  generally  made  of  greater  lift 
or  fall  than  where  the  ground  is 
comparatively  flat  and  water  scarce. 
It  is  evident,  that  where  the  super- 
ficial area  of  locks  is  the  same,  one 
having  a  rise  of  12  feet  would  re- 
quire  twice  the  quantity  of  water 
to  fill  it  that  would  be  requisite  for 
one  of  6  feet.  Having  many  locks, 
however,  of  small  lifts  instead  of  a 
few  of  greater,  increases  the  ex- 
pense, as  well  as  the  time  for  pass- 
ing them. 

For  narrow  canals  these  locks 
are  generally  made  about  80  feet 
long,  and  7  Mo  8  feet  wide  in  the 
chamber.  On  the  Caledonian  canal 
they  are  180  feet  long,  40  feet  wide, 
and  30  feet  deep.  Locks  are  also 
constructed  of  every  intermediate 
size. 

Lock-gates  have  till  lately  been 
made  of  timber;  but  in  consequence 
of  the  difficulty  of  procuring  it  of 
sufficient  size  for  those  on  the 
Caledonian  canal,  cast  iron  was 
partially  adopted  for  the  heads, 
heels,  and  ribs.  Iron  gates,  cast  in 
one  piece,  have  been  used  on  the 
Ellesmere  canal,  as  well  as  others 
with  cast-iron  firaming  and  timber 
planking. 

Locks  with  side  ponds. — ^When  water 
is  scarce,  it  is  common  to  construct 
side  ponds,  by  which  a  considerable 
portion  (in  general  one -half)  is 
saved.  The  usual  number  of  these 
ponds  is  two ;  for  it  has  been  de- 
termined by  experience,  that  when 
a  greater  number  has  been  made 


LOG 


LOCKS,  PARALLEL  DOUBLE- TRANS  IT. 


LOC 


use  of,  the  loss  occasioned  by  leak-  | 
age  and  evaporation  has  sometimes 
been  more  than  equal  to  the  ad- 
ditional quantity  of  water  thus  re- 
tained. 

Locks  for  the  transit  of  vessels  of 
(liferent  sizes, — Where  vessels  of 
different  sizes  have  to  pass  the 
same  locks,  three  pairs  of  gates  are 
sometimes  placed  instead  of  two, 
— ^the  distance  between  the  upper 
and  lower  pairs  being  sufficient  to 
admit  the  largest  vessels,  and  that 
between  the  upper  and  middle  pairs 
being  adapted  to  the  smaller  class. 
By  this  contrivance,  when  a  small 
vessel  is  to  be  passed  through,  the 
lowest  pair  of  gates  is  not  used ;  and 
when  a  large  vessel  goes  through, 
the  middle  pair  of  gates  is  not 
worked.  Thus  it  is  evident  that 
the  quantity  of  water  contained 
between  the  middle  and  lower  pair 
of  gates  is  saved  when  a  small  ves- 
sel passes,  compared  with  what 
would  be  required  were  the  middle 
set  of  gates  omitted. 

Locks  (parallel  double  -  transit), — 
Where  the  transit  is  great,  much 
time  and  water  may  be  saved  by  a 
double-transit  lock,  which  is  two 
locks  placed  close  to  and  parallel 
with  each  other,  with  a  communi- 
cation between  them,  which  can  be 
opened  or  cut  off  at  pleasure  by 
valves  or  paddles. 

As  one  of  these  locks  is  kept  full 
and  the  other  empty,  a  vessel  in 
descending  floats  into  the  full  one: 
the  upper  gates  are  then  closed, 
and  the  water  is  run,  by  means  of 
the  connecting  culvert,  into  the 
empty  lock  (the  gates  of  which 
were  previously  closed),  till  the 
water  in  the  two  locks  is  on  the 
same  level,  which  will  be  when 
each  is  half-full :  the  connecting 
paddles  are  then  closed,  and  the 
remaining  half  of  the  water  in  the 
descending  lock  is  run  into  the 
lower  canal.  The  next  descending 
vessel  has  to  be  floated  into  the 
lock  which  remains  half-filled,  and 
I     which  consequently  requires  only 


half  a  lock  of  water  to  be  run  from 
the  upper  pond  to  raise  it  to  the 
proper  level,  and  then  that  half  is 
transferred  to  the  lock  previously 
used,  to  serve  the  next  descending 
vessel;  but  supposing  a  vessel  to 
be  ascending  after  the  first  descent, 
it  will  enter  the  empty  lock,  and 
receive  a  quarter-lock  of  water  from 
that  which  remained  half-filled :  of 
course,  three-quarters  of  a  lock  of 
water  is  now  required  from  the 
upper  canal  to  complete  the  filling. 
If  a  descending  vessel  next  follows, 
it  enters  the  full  lock,  and  its  water 
is  run  into  the  lock  which  was 
previously  left  a  quarter-fuU;  and 
when  both  have  arrived  at  the  same 
level,  it  is  evident  they  will  be  each 
five-eighths  full,  and  the  succeeding 
descending  vessel  will  require  only 
three-eighths  of  a  lock  of  water 
from  the  upper  pond  or  canal 
From  these  observations,  it  wiU  be 
seen  that  the  double -transit  lock 
saves  nearly  one-half  of  the  water 
which  a  common  single  lock  would 
require. 

Sometimes  the  two  parallel  locks 
are  made  of  different  sizes,  to  suit 
the  various  descriptions  of  vessels 
that  may  have  to  pass. 
Locks  connected  longitvdmaUyi  com- 
monly called  a  Chain  of  Locks.— 
Wlien  loss  of  water  is  of  no  conse- 
quence, a  considerable  expense  is 
sometimes  saved  by  placing  the 
locks  close  together,  without  any 
intermediate  pond ;  for  by  passing 
from  one  immediately  into  the 
other,  there  is  only  required  one 
pair  of  gates  more  than  the  number 
of  locks  so  connected,  besides  a 
proportionate  saving  of  masonry. 
Thus,  eight  connected  locks  would 
only  require  nine  pairs  of  gates; 
whilst,  if  they  were  detached,  they 
would  require  sixteen  pairs.  But 
to  show  that  these  cannot  be  adopt- 
ed, with  propriety  excepting  where 
water  is  abundant,  it  is  necessary 
to  observe,  that  every  two  alternate 
ascending  and  descending  vessels 
will  require  as  many  locks-full  of 


LOC 


LOCOMOTIVE  STEAM  ENGINES. 


LOC 


water  as  there  are  locks:  for  in- 
stance,  if  a  vessel  has  just  ascended, 
it  has  left  all  the  locks  full ;  a  de- 
scending vessel  then   enters   the 
upper  lock,  and  when  its  gates  are 
closed,  the  water  is  run  down ;  but 
all  the  locks  below  being  previously 
filled,  they  cannot  contain  it,  and 
it  consequently  passes   over   the 
gates  or  weirs  of  all  of  them  into 
the  lower  canal :  the  vessel  has  by 
this  means  descended  to  the  level  of 
the  second  lock,  the  water  in  which 
must  also  be  run  into  the  lower 
canal,  for  the  same  reason  as  al- 
ready stated.    When  the  water  of 
all  the  locks  has  thus  been  run 
down,  an  ascending  vessel  will  re- 
quire all  these  locks  to  be  filled 
from  the  upper  canal,  which,  how- 
ever, will  be  retained  in  the  locks 
ready  for  the  succeeding  vessel  to 
pass  down.     From  this  it  will  be 
evident,    that  where   eight  locks 
are  connected,  a  descending  vessel 
draws  no  water  from  the  upper 
canal,  because  the  locks  are  pre- 
viously all  filled,  but  it  empties 
eight  locks  of  water  into  the  lower 
canal :  an  ascending  vessel,  on  the 
contrary,   empties  no  water  into 
the  lower  canal,  because  all  the 
locks  were  previously  emptied,  but 
it  draws  eight  locks-full  from  the 
upper  canal,  in  order  to  fill  them : 
consequently,  the  passing  of  one 
ascending  vessel,  and  one  descend- 
ing,  requires  eight  locks -full  of 
water. 

Other  modes  of  passing  vessels 
from  one  level  to  another,  by  sub- 
stituting machinery,  either  wholly 
or  in  part,  have  been  adopted ;  but 
these  have  either  failed  entirely,  or 
have  not  been  brought  into  general 
use. 
Locomotive  Steam  Engines,  a  class  of 
travelling  machines  adapted  either 
for  railways  or  common  roads, 
were  originally  designed  for  the 
latter,  but  did  not  succeed;  and 
roads  were  then  made  for 'them, 
called  railways,  on  which  they  have 
been  most  successful.  The  principle 


of  action  being  the  same  in  both 
kinds,  a  description  of  the  railway 
variety  will  explain  the  manner  in 
which  progressive  motion  is  obtain- 
ed by  the  agency  of  steam. 

Locomotion  or  progression  is  the 
combined  effect  of  a  number  of 
parts  in  each  engine  performing 
separate  duties.  The  principal  of 
these  parts  and  the  plan  of  their 
co-operation  may  be  thus  classed : 
1st.  The  parts  which  generate  the 

steam. 
2nd.  The  parts  which  regulate  the 

employment  of  the  steam. 
3rd.  The  parts  by  which  the  driver 
controls  the  action  of  the  engine. 
4th.  The  parts  immediately  con- 
cerned in  producing  locomotion. 
5th.  The  parts  which  excite  the 

rapid  combustion  of  the  fueL 
€th.  The  parts  which  supply  water 

to  the  boiler. 
7th.  The  parts  which  support  the 

engine  on  the  rails. 
8th.  The  manner  in  which  loco- 
motion is  produced  by  these  parts. 
In   explaining  them  and  their 
effect  as  thus  arranged,  we  have 

1st,  The  parts  which  generate 
the  steam,  called  the  boiler,  con- 
taining internally  a  fire-box,varying 
according  to  the  dimensions  of  the 
engine  from  25  (as  in  the  'Rocket') 
to  303  small  tubes  (as  in  the  broad- 
gauge  engines),  a  regulator,  and 
a  steam-pipe.  Externally,  a  chim- 
ney and  two  safety-valves  are  fixed 
to  the  boiler. 

2ndly,  The  parts  which  regulate 
theemploymentof  the  steam  are, two 
slide-valves  (covering  the  passages 
to  and  from  the  cylinders),  attached 
to  two  sets  of 'valve-gear,*  worked 
by  two  eccentrics  for  the  *  forward' 
and  two  other  eccentrics  for  the 
'backward '  motion  of  the  engine ; 
but  only  two  of  them  work  at  one 
time,  the  other  two  being  what  ia 
called  'out  of  gear.'  Four  rods 
called  eccentric-rods,  encircling  the 
eccentric-sheaves  at  one  end,  and 
jointed  to  the  slide-valve  gear  at 
the  other  end,  complete  the  con- 


263 


LOG 


LOCOMOTIVE  STEAM  ENGINES. 


LOC 


nection  of  the  slide-valTes  to  the 
eccentrics  fixed  on  the  axle  of  the 
driving  wheels. 

3rdly,  The  parts  by  which  the  dri- 
ver controls  the  action  of  the  engine 
are,  three  sets  of  levers  and  rods 
connected  to  the  slide-valve,  eccen- 
tric-rods, regulator- valves,andfeed- 
pipe  cocks,  whereby  he  can  '  put 
on'  or  <  shut  off*  steam  to  the  cy- 
linders, water  to  the  boiler,  or 
place  the  slide-valves  in  a  'for- 
ward' or  'backward'  position  at 
his  pleasure.  These  arrangements 
are  usually  called  the  '  hand-gear.' 
4thly,  The  parts  immediately  con- 
cerned in  producing  locomotion 
are,  two  cylinders,  on  which  work 
two  steam-tight  pistons,  fixed  on 
the  end  of  the  piston-rods.  On  the 
open  end  of  the  piston-rods  are 
also  fixed  T- pieces,  called  cross- 
heads,  which  slide  between  or 
round  guide-bars,  called  motion- 
bars,  fixed  parallel  with  the  cylin- 
ders. By  this  means  the  pistons 
can  only  move  in  a  right  line  with 
the  cylinders.  Two  strong  rods, 
called  connecting-rods,  attach  the 
cross-heads  to  the  driving  wheels, 
or  to  a  cranked  axle  when  there  is 
one  used.  Whether  the  pistons 
are  connected  to  a  cranked  axle  or 
to  the  arms  of  the  driving  wheels, 
this  connection  is  always  made  at 
an  angle  of  45  degrees  to  each 
other;  therefore  the  one  piston  is 
in  the  centre  of  the  cylinder  exert- 
ing its  greatest  power  during  that 
part  of  the  stroke  when  the  other 
piston  is  at  the  end  of  the  cylinder 
exerting  no  power.  (This  excel- 
lent arrangement  was  amongst  the 
first  improvements  introduced  by 
the  late  Mr.  G.  Stephenson,  in 
1814,  who  thus  placed  the  locomo- 
tive in  the  same  high  position,  as  to 
efliciency,  as  was  previously  done 
for  fixed  engines  by  Watt.)  The 
connection  being  thus  completed 
between  the  pistons  and  the  driv- 
ing wheels,  it  is  evident  that  any 
movement  of  the  one  must  imme- 
diately act  upon  the  other. 

f— ] — 

264 


5thly,  The  parts  which  excite  the 
rapid  combustion  of  the  fuel  re- 
quired in  locomotive  engines  are, 
the  chimney  and  a  pipe  called  the 
blast-pipe,  so  made  as  to  cover  the 
exhausting  passages  from  both  cy- 
linders, and  terminating  in  the 
centre  of  the  chimney,  near  the 
level  of  the  top  of  the  boiler.  It 
is  the  escape  through  this  pipe  of 
each  succeeding  cylinder-full  of 
steam,  or  that  portion  of  it  allowed 
to  escape  by  the  slide-valves,  which 
causes  the  'beats'  or  'pulsations' 
so  distinctly  audible  when  the 
locomotive  is  at  work. 

6thly,  The  parts  which  supply 
water  to  the  boiler  are,  two  force- 
pumps,  connected  by  two  feed- 
pumps to  the  boiler,  and  to  a  re- 
servoir of  water.  The  pumps  are 
worked  either  from  the  cross-head, 
or  ffOBi  eccentrics  on  the  axle  of  the 
driving  wheels. 

7thly,  The  parts  which  support 
the  engine  are,  2,  4  or  6  wheels, 
besides  the  driving  wheels,  a  set  of 
springs,  and  a  strong  frame  on 
which  the  boiler  and  machinery  are 
securely  fixed. 

Sthly,  The  manner  in  which  lo- 
comotion is  produced  from  the  co- 
operation of  these  several  parts  is 
as  follows.  The  boiler  is  filled 
with  water  until  it  completely  sur- 
rounds all  the  tubes  and  inside  fire- 
box. Fire  is  then  applied,  and  in 
due  time  steam  is  generated  from 
the  water  and  collected  between 
the  surface  of  the  water  and  the 
top  of  the  boiler,  until  it  has 
reached  the  pressure  required.  On 
the  regulator  being  then  opened, 
and  the  slide-valves  placed  in  their 
working  position  by  the  driver,  the 
steam  passes  from  the  boiler  through 
the  steam-pipe  to  the  cylinders, 
where  its  force  moves  the  pistons, 
which,  being  attached  to  the  driv- 
ing wheels  (as  has  been  explained), 
causes  them  to  revolve,  and  thus 
produces  locomotion.  The  slide- 
valves  and  pumps  being  wrought 
from  some  part  set  in  motion  by 


LOG 


LOCOMOTIVE  ENGINES. 


LOG 


the  piston,  regulate  the  admission 
of  steam  to  the  cylinder,  and  of 
water  to  the  hoiler.  When  the 
steam  has  moved  the  piston  to  the 
end  of  the  cylinder^  a  passage  is 
opened  for  its  escape  to  the  atmo- 
sphere through  the  blast-pipe,  and 
the  velocity  of  this  escaping  steam 
creates  a  partial  vacuum  in  the 
chimney,  causing  a  rush  or  '  blast' 
of  air  tlut)ugh  the  fire  to  fill  this 
vacuum;  which  blast  excites  the 
rapid  combustion  of  the  fuel,  and 
consequent  rapid  generation  of 
steam.  This  completes  the  duties 
of  one  admission  of  steam  to  the 
cylinders,  until  its  escape  to  the 
atmosphere ;  and  when  this  escape 
has  taken  place,  another  admission 
of  steam,  to  the  opposite  side  of 
the  piston,  forces  it  back  to  the 
other  end  of  the  cylinder ;  and  by 
the  [medium  of  the  crank,  the  re- 
ciprocating motion  of  the  piston  is 
converted  into  a  rotatory  one,  and 
the  locomotion  begun  by  the  first 
admission  of  steam  to  the  cylinders 
is  continued  by  the  second  and 
succeeding  admissions. 

The  repetition  of  these  simple 
operations  has  amazed  and  gratified 
the  world,  by  safely  conveying 
heavy  passenger  trains  at  upwards 
of  70  imles  an  hour,  and  merchan- 
dise trains  of  600  tons  weight,  at 
25  miles  per  hour ! — ^the  mere  idea 
of  which,  not  many  years  since, 
would  have  been  regarded  as  purely 
fabulous. 

Such  is  the  modem  railway  loco- 
motive,— an  illustrative  example  of 
the  genius  of  man ;  but,  like  other 
important  inventions,  it  is  the 
joint  production  of  many  minds, 
and  many  more  are  still  directed 
to  its  further  improvement.  The 
records  of  the  Patent  Ofiice  show, 
that  from  January,  1840,  to  the 
end  of  September,  1849,  no  less 
than  226  patents  were  enrolled,  all 
of  them  more  or  less  applicable 
to  the  steam  engine  and  its  ap- 
pendages. Of  these  226  patents, 
45  were  enrolled  during  the  first 


nine  months  of  1 849.  It  has  been 
remarked  that  steam  engines  and 
railways  were  too  matter-of-fact 
subjects  for  poets  and  painters;  but 
from  the  above  record  it  is  evident 
that  they  deeply  impress  them- 
selves upon  the  inventive  intellect 
of  the  world;  and  if  the  prodigies 
performed  by  steam  remain  un- 
sung or  unportrayed,  they  dare,  if 
not  realize,  the  very  sublimity  of 
both  poetry  and  painting ;  for  what 
more  interesting  scene  to  delineate 
than  one  of  these  stately  machines 
moving  safely  along,  at  eagle-speed, 
the  very  ^lite  of  the  land,  (including 
even  the  Royal  Family,)  through 
districts  rich  in  the  historical  as- 
sociations of  past  ages,  and  still 
teeming  with  the  works  of  nature 
and  of  art!  Surely  it  cannot  be 
that  the  subject  is  too  lofty  a  one 
for  poetical  or  pictorial  illustration, 
for  in  greatness  of  idea  lies  the 
success  of  both. 

A  brief  review  of  the  progress  of 
locomotive  engines  is  all  that  can 
be  here  given.  It  is  now  (1849) 
about  2000  years  since  the  powers 
of  steam  were  recorded  by  Hero  of 
Alexandria,  but  it  is  only  200  years 
(in  1650)  since  it  was  first  usefully 
employed  by  the  Marquis  of  Wor- 
cester. The  first  idea  of  using  it 
for  propelling  carriages  is  generally 
ascribed  to  Dr.  Robison,  in  1759, 
when  it  was  suggested  by  him  to 
Watt,  who  included  a  steam  carriage 
in  his  patents  of  1769  and  1784, but 
never  carried  them  out.  In  1 786, 
Oliver  Evans,  of  Philadelphia,  had 
clear  perceptions  of  the  advantages 
of  applying  steam  to  waggons, 
boats,  and  mills ;  but  the  want  of 
friends  and  means  compelled  him 
to  confine  his  exertions  to  steam 
mills.  From  1802  to  1805,  Trevi- 
thick  applied  steam  carriages  to 
both  common  roads  and  railways, 
with  considerable  success  for  first 
experiments ;  and  his  engine,  with. 
Stephenson's  improvements,  is  now 
the  modem  locomotive.  About  the 
year  1803,  it  appears  that  a  Mr. 


265 


LOG 


LOCOMOTIVE  ENGINES. 


LOG 


i 


Frederidcs  also  made  a  steam  en- 
gine for  a  silver  mine  in  Hanover, 
which,  in  1811,  was  employed  to 
convey  their  Mijesties  and  suite  of 
Westphalia  over  the  mineral  rail- 
way at  considerable  speed.  This 
was  probably  the  first  royal  trip  on 
a  railway.  From  1805  up  to  1814, 
invention  was  directed  to  insure 
the  adhesion  of  the  wheels  upon 
the  rails;  and  many  ingenious  plans 
were  tried,  some  of  which  succeeded 
well  at  slow  speeds,  but  were  not 
calculated  for  high  velocities.  In 
1814,  however,  Mr.  Blackett,  of 
the  Wylam  Railway,  reverting  to 
Trevithick's  plan,  fully  established 
the  FA.CT,  that  on  a  level,  or  mo- 
derately inclined  railway,  the  ad- 
hesion of  a  smooth  iron  wheel  upon 
a  smooth  iron  rail  was  sujQScient 
to  draw  heavy  loads.  He  tried  both 
six  and  eight  wheeled  engines.  In 
1814,  Mr.  Stephenson  introduced 
two  cylinders,  or  two  complete 
steam  engines,  to  one  locomotive* 
From  this  time  up  to  1829,  the 
powerful  opposition  of  the  owners 
of  other  modes  of  conveyance 
greatly  retarded  the  progress  of 
the  locomotive  engine;  and  so 
strong  was  the  feeling  that  they 
were  not  economical,  that  both 
Mr.  Walker  and  Mr.  Rastrick  re- 
ported against  them,  in  1829. 
These  reports,  and  one  of  a  doubt- 
ful character  by  Telford,  led  to  the 
offer  of  a  prize  of  £500,  in  1829, 
by  the  directors  of  the  Liverpool 
and  Manchester  Railway,  for  the 
best  locomotive  engine,  whose 
weight  was  not  to  exceed  six  tons. 
This  proceeding  gave  an  important 
impulse  to  locomotives,  and  ended 
in  establishing  their  superiority 
over  all  other  existing  systems  of 
travelling.  Five  competitors  ap- 
peared, namely,  Messrs.  Stephen- 
son, Erickson,  Hockworth,  Burstal, 
and  Brandreth.  The  machinery  of 
the  two  last  were  not  suitable,  and 
did  not  proceed  to  trial.  Mr. 
Stephenson's  '  Rocket,'  Mr.  Erick- 
son's  *  Novelty,'  and  Mr.   Hock- 

266 


worth's  *  Sanspareil,'  were  all  tried, 
and  the  prize  was  fairly  won  by  the 
*  Rocket,'  which,  after  the  trials 
were  over,  reached  a  speed  of  35 
miles  per  hour,  and  the  *  Novelty' 
about  24  mUes  per  hour. 

The  *  Rocket '  embraced  the  fire- 
box, tubes,  and  blast-pipe  of  the 
modem  locomotive. 

The  'Novelty'  embraced  the 
plan  now  much  used  on  short  lines, 
of  carrying  engine,  fuel,  and  water, 
all  on  one  frame. 

The  'SanspareU'  embraced  the 
blast-pipe  of  the  modem  engine, 
with  the  single  returned  tube  of  the 
older  locomotives.  From  this  it 
will  be  seen  that  this  competition 
at  once  brought  out  the  leading 
features  which  have  since  rendered 
the  locomotive  engine  so  popular 
throughout  the  world. 

From  1830,upto  the  introduction 
of  the  7 -feet  gauge  on  the  Great 
Westem  Railway,  in  1838,  no 
marked  improvement  took  plaice  in 
the  locomotive,  but  the  rivalry 
which  spmng  up  between  the 
gauges  served  greatly  to  develop 
their  capabilities. 

Engines  of  a  novel  constraction, 
having  the  boiler  on  one  frame,  and 
the  machinery  on  another  friune, 
were  tried  on  the  Great  Western 
Railway;  also  engines  embracing 
Trevithick's  plan  of  working  the 
driving  wheels  by  toothed  wheels, 
fixed  on  a  separate  cranked  axle, 
were  tried,  but  all  abandoned  for 
engines  modelled  from  one  of 
Stephenson's;  and  the  last  new 
Great  Westem  engines  only  follow 
up  his  latest  improvements  and 
Gray's  expansive  slide-valve  motion 
on  a  large  scale. 

A  number  of  patents  have  been 
enrolled  for  improving  the  loco- 
motive engine,  but  a  few  only  have 
been  reduced  to  practice. 

Amongst  the  more  conspicuous 
of  them  are,  Mr.  Stephenson's  im- 
provements in  the  slide-valve  mo- 
tion ;  Mr.  Gray's  expansive  mo- 
tion ;  Mr.  Crampton's  arrangement 


LOC 


LOCOMOTIVE  ENGINES. 


LOC 


of  wheels ;  Mr.  Bodmer's  arrange- 
ment of  four  pistons  in  two  cylin- 
ders; Mr.  M'Connell's  tank  engine ; 
Mr.  Samuel's  express  engine ;  and 
Mr.  Adam's  steam  carriage.  The 
improvements  in  the  mechanism 
of  the  slide-valve  motion,  by  Messrs. 
Stephenson  and  Gray,  have  been 
widely  adopted.  Mr.  Crampton 
has  engines  of  his  plan  at  work 
both  in  England  and  on  the  Con- 
tinent, which  enable  high  driving 
wheels  to  be  used  on  the  narrow 
gauge,  without  raising  the  centre 
of  gravity.  (For  an  illustration  of 
these  and  other  examples,  see  the 
new  edition  of  'Tredgold  on  the 
Steam  Engine.') 

Mr.  Bodmer's  plan  is  to  admit 
the  steam  between  two  pistons  in 
one  cylinder  acting  on  two  cranks, 
so  as  to  compensate  the  strain  on 
the  frame  and  machinery.  His 
engines  work  steadily,  and  are  in- 
genious in  construction. 

The  Tank  engine  carries  on  the 
same  frame  water  and  fuel,  its  tank 
for  water  being  placed  on  the  top 
of  the  boUer.  This  is  the  plan 
adopted  on  the  Great  Western  Rail- 
way; but  on  narrow-gauge  lines 
the  tank  is  usually  placed  below 
the  boiler  and  framing, — a  better 
arrangement,  where  the  machinery 
permits  it  to  be  done. 

Mr.  Samuel's  express  engine 
weighed  only  25  cwt.,  and  con- 
veyed seven  passengers  at  the  rate 
of  30  miles  per  hour  on  the  Eastern 
Counties  Ridlway. 

Mr.  Adam's  steam  carriage  is  on 
this  plan,  with  a  very  handsome 
carriage  for  passengers,  all  on  one 
frame,  and  has  been  tried  on  some 
of  the  branch  railways  of  both 
gauges. 

Having  thus  briefly  glanced  at  the 
progress  of  the  locomotive  engine, 
it  only  remains  as  briefly  to  notice 
some  important  discussions  which 
have  agitated  the  mechanical  world 
regarding  them. 

From  the  earliest  introduction  of 
locomotives,  four,  six,  or  eight  wheels 

267 


appear  to  have  been  used,  according 
to  the  designs  of  the  makers ;  but 
about  1840-1-2,  an  animated  dis- 
cussion of  the  respective  merits  of 
the  four  and  sixwheeled  engines  was 
carried  on  in  the  columns  of  the 
railway  press.  Both  classes  have 
their  merits,  and  both  classes  had 
able  advocates,  but  public  opinion 
evidently  tended  in  favour  of  the 
six-wheeled  engine  as  the  safer  of 
the  two  under  all  contingencies: 
hence  the  greater  proportion  of  the 
present  locomotives  have  six  wheels. 

The  gauge  controversy  of  1845- 
6-7-8  led  to  the  re-introduction  of 
eight-wheeled  engines  on  both 
gauges,  weighing  about  36  tons 
each,  which  realized  speeds  of  about 
sixty  and  seventy  miles  per  hour. 
The  weight  of  these  monster  en- 
gines, it  will  be  observed,  is  more 
than  eight  times  that  of  the  *  Rocket' 
(4^  tons),  which  won  the  prize  in 
1829,  whilst  the  speed  is  only  twice 
that  of  the  *  Rocket'  (thu^y.five ' 
miles)  at  that  time.  It  is  worthy 
of  remark,  that  in  1829  the  exist- 
ing engines  of  10  to  16^  tons  were 
considered  as  far  too  heavy,  and  the 
Liverpool  and  Manchester  directors 
bound  competitors  not  to  exceed  six 
tons  weight.  In  1849,  the  same  feel- 
ing prevailed,  and  the  injury  done 
to  the  railway  by  these  36  tons 
engines  is  much  complained  of,  and 
tank  engines  and  steam  carriages 
embody  this  feeling  in  practice. 

A  description  of  the  locomotive 
can  scarcely  be  closed  without  no- 
ticing the  death  of  its  great  im- 
prover, Mr.  G.  Stephenson,  who 
died  in  1848,  aged  68  years. 

He  found  the  locomotive  a  very 
imperfect  machine ;  he  left  it  in  that 
efScient  state  that  even  the  daring 
genius  of  a  Brunei  could  only  copy 
his  plans  for  the  7-feet  gauge.  Thu 
is  another  testimony  to  that  far- 
seeing  intellect  wMch  so  early 
grasped  the  principal  requisites  for 
an  eflteient  locomotive,  and  whose 
genius  coped  with  and  overcame 
the  leading  engineers  of  England, 


LOG 


LOGARITHMS. 


LOG 


in  1829,  by  establishing  both  loco- 
motives and  the  Liverpool  and 
Manchester  Railway  against  all  op- 
position, and  from  which  sprung 
that  system  of  railways  which  has 
added  so  immensely  to  the  resources 
of  the  nation — ay,  of  the  world. 

Civil  services,  military  services, 
naval  services,  and  no  services,  have 
at  all  times  been  liberally  reward- 
ed by  the  Crown  and  Legislature; 
but  there  are  no  such  rewards,  no 
OBDEB  or  MERIT  for  such  men  as 
Stephenson,  Watt,  Arkwright,  &c., 
who  are  the  mainstays  of  our  pro- 
gress, our  greatness,  and  our  power. 
This  is  wrong — very  wrong,  and 
ought  to  be  amended.  However, 
if  the  Crown  forget,  and  the  Legis- 
lature neglect  such  men,  it  is  con- 
solatory to  know,  that  their  names 
will  be  embalmed  in  the  hearts  of 
the  people,  whilst  the  profligacy  of 
honours  and  rewards  to  those  hav- 
ing no  real  claim  on  the  gratitude 
of  the  nation  is  universally  con- 
demned. 

Upon  the  Taunus  Railway,  an 
apparatus  is  in  use,  invented  by 
Mr.  Thorman,  which,  from  its 
simplicity  and  efficiency,  cannot 
easily  be  excelled.  It  is  attached 
to  the  hinder  part  of  the  tender, 
and  is  used  in  case  of  emergency, 
as  well  as  being  constantly  used 
when  at  the  stations,  where  it  is 
necessary  to  uncouple  the  engine 
and  tender  from  the  train,  thereby 
saving  great  trouble,  and  with  less 
danger  to  engine-men  and  fire-men, 
as  they  can  disconnect  at  any  speed 
or  at  any  time,  whether  the  engine 
and  train  are  in  motion  or  not.  (For 
a  better  elucidation  of  this  simple 
and  ingenious  contrivance,  see 
Thorman's  work  on  the  *  Taunus 
Railway,'  4to,  1846.) 

Locker,  a  small  closet  or  cupboard: 
lockers  were  used  in  churches  to 
hold  sacred  relics 

Locust'tree  (the)  of  North  America  is 
of  a  greenish  yellow ;  is  tough  and 
durable,  and  used  for  treenails  for 
ships,  for  posts,  stakes,  paling,  &c. 

268  ~~ 


Lodct  a  metallic  vein 

Lqftt  a  room  in  the  roof  of  a  build- 
ing ;  a  store-room  in  a  theatre ;  a 

-  depository  for  hay  and  com  in  a 
stable :  a  music  loft ;  a  singing  loft; 
a  rood-loft  in  a  church 

Lofty  tiny  rich,  massive,  and  rough  tin 

Log^  in  navigation,  a  small  triangular 
piece  of  board  balanced  by  a  thin 
plate  of  lead  so  as  to  swim  perpen- 
dicularly, and,  being  fixed  to  aline, 
measures  the  ship's  way 

LogarithtM  are  the  artificial  numbers 
used  to  facilitate  or  abridge  aiith- 
metical  calculations,  and  may  be 
considered  as  expressing  the  rela- 
tion between  an  arithmetical  and 
geometrical  series  of  terms,  or 
between  ratios  and  the  measures  of 
ratios,  and  are  the  indices  or  ex- 
ponents of  a  series  of  numbers  in 
geometrical  progression.  The  ori- 
gin and  nature  of  logarithms  may 
be  easily  explained. 

In  arithmetical  series  the  qnan- 
titles  increase  or  decrease  by  the 
same  difference,  but  in  a  geome- 
trical series  they  increase  or  dimi- 
nish by  a  common  measure.  The 
first  of  the  following  lines  exhibits 
an  arithmetical  progression;  ail  the 
other  hues  are  examples  of  geome- 
trical progression. 
1—0,  1,2,3,4,  5,6,7,8,9. 
2—1,  2,  4»  8,  16,32,  64, 128, 256, 

512. 
3—1,  3,  9,  27,  81,  243,  729, 2187, 

6561,  25683. 
4—1,  10,  100,  1000,  10,000,  &c. 

Here  consider  the  upper  line  as 
the  index  to  all  the  rest;  every 
term  of  it  is  the  logarithm  of  a 
correspondingterm  in  each  of  them; 
and  it  is  evident  that  an  infini- 
tude of  other  lines,  or  any  one  of 
the  same  lines,  varying  the  pomt 
of  commencement,  and  containing 
numbers  in  geomeliicalprogpression, 
might  be  added,  to  all  of  which  the 
same  arithmetical  series  might  fur- 
nish logarithms. 

Logeunit  the  pulpitum  or  wooden 
stage  ci  a  theatre,  placed  upon  the 
proscenium  or  permanent   stage. 


LOM 


LOMBARDIC  SCHOOL. 


LYS 


In  the  Greek  theatre  the  pulpitum 
extended  into  the  orchestra  heyond 
the  proscenium. 

Loffwood,  from  Campeachy,  Jamaica, 
Honduras,  &c.,  is  burgely  used  as  a 
purple  or  dark  red  dye-wood 

Loinbardic  Architecture^  a  style  which 
immediately  succeeded  the  decline 
of  the  Roman  style 

Lombardic  School  of  Pamting,  The 
distinguishing  characteristics  of  this 
school  are,  grace,  an  agreeable  taste 
for  design,  without  great  correc- 
tion, a  mellowness  of  pencil,  and 
a  beautiful  mixture  of  colours.  An- 
tonio AHegri,  called  Correggio,  was 
the  father  and  the  greatest  orna- 
ment of  this  school :  he  began  by 
imitating  nature  alone,  but  as  he 
was  chiefly  delighted  with  the 
graceful,  he  was  careful  to  purify 
his  design;  he  made  his  figures 
elegant  and  large,  and  varied  his 
outlines  by  frequent  undulations, 
but  was  not  always  pure  and  cor- 
rect, though  bold  in  his  concep- 
tions. Correggio  painted  in  oil,  a 
kind  of  painting  susceptible  of  the 
greatestdelicacy  and  sweetness;  and 
as  his  character  led  him  to  cultiyate 
the  agreeable,  he  gave  a  pleasing, 
captivating  tone  to  all  his  pictures. 

London  and  Nottingham  whites.  The 
best  of  these  do  not  differ  in  any 
essential  particulars  materially,  nor 
from  the  white  leads  of  other  ma- 
nufactories. The  latter,  being  pre- 
pared from  flake-white,  is  gene- 
rally the  grayest  of  the  two.  The 
inferior  white  leads  are  adulterated 
with  whiting  or  other  substances, 
which  injure  them  in  body  and 
brightness,  dispose  them  to  dry 
more  slowly,  to  keep  their  place 
less  firmly,  and  to  discolour  the  oil 
with  which  they  are  applied.  All 
the  above  are  carbonates  of  lead, 
and  liable  to  froth  or  bubble  when 
used  with  aqueous,  spiritous,  or 
add  preparations. 

Longitude,  length;  the  distance  of 
any  part  of  the  earth,  east  or  west, 
from  London,  or  any  other  given 
place 

269 


Long  timbers,  in  ship-building,  those 
timbers  in  the  cant  bodies  which 
reach  from  the  dead-wood  to  the 
second  futtock-head 

Loobs,  tin  slime  or  sludge 

Loqf,  in  navigation,  pronounced  hijff^, 
a  term  applied  when  a  ship  going 
large  before  the  wind,  is  brought 
close  by  the  wind ;  to  put  the  helm 
towards  the  lee-side 

Loop-hole,  a  narrow  opening  or  cre- 
nelle used  in  the  battlements  of  the 
castles  of  the  early  English 

Lord  of  the  land  or  tree,  in  Cornwall, 
the  person  in  whose  land  the  mine 
is ;  therefore  the  part  which  he  re- 
serves to  himself  for  liberty  to  work 
a  mine  in  his  land  is  the  one-sixth, 
one-seventh,  one-eighth,  or  any 
other  proportion,  free  of  expense, 
and  c£dled  the  *  dues'  dish' 

Louvre,  a  lantern;  a  turret  on  the 
roof  of  an  ancient  hall  or  kitchen 
for  the  escape  of  smoke  and  for 
ventilation,  now  made  an  orna- 
mental and  pleasing  object 

Lozenge,  in  geometry  called  a  rhomb, 
and  when  the  sides  are  unequal,  a 
rhomboid ;  in  heraldry,  a  four-cor- 
nered figure,  resembling  a  pane  of 
glass  in  old  casements. 

Lozenge  moulding,  a  name  given  to 
the  Norman  style  of  mouldings  and 
ornaments,  which  are  shaped  like 
lozenges 

Lubricate,  to  make  smooth  or  slippery 

Lubricator,  an  oil-cup  or  other  con- 
trivance for  supplying  oil  or  grease 
to  rubbing  smfaces,  in  order  to 
diminish  friction 

Lucema,  an  oil-lamp.  The  Greeks 
and  Romans  originally  used  can- 
dles; but  in  later  times  these 
were  chiefly  confined  to  the  houses 
of  the  lower  classes 

Lugsail,  in  navigation,  a  small  sail 
hoisted  occasionally  on  the  mast 
of  a  boat  or  small  vessel 

Lychnus,  a  lamp  suspended,  or  a  pen- 
dent light 

Lgsis,  some  member  above  the  corona 
of  a  podium,  introduced  in  temples, 
and  in  the  scene  of  a  theatre 


M  3 


MAC 


MACHINERY. 


MAC 


MAC 

Machinjie  Organa,  defined  by  Vi- 
truyius,  in  his  10th  book,  as  con- 
trivances for  the  concentration  and 
application  of  force,  which  are 
known  by  the  names  of  instru- 
ments, mechanical  powers,  ma- 
chines, engines,  &c. 

Machinery y  a  general  term  applied  to 
mechamcal  combinations  of  parts 
for  creating  power,  or  producing 
works  which  may  otherwise  be, 
more  or  less  perfectly,  made  with 
the  hands.  The  first  class  of  these 
combinations  is  usually  distin- 
guished by  the  name  of  engines ; 
the  second,  by  that  of  machines. 

Engines,  or  machines  for  creat- 
ing or  accumulating  and  applying 
power,  are  distinguished  from  each 
other  according  to  the  material 
employed  in  the  creation  of  their 
power,  as  air-engines,  water-en- 
gines, gas-engines,  steam-engines, 
electric-engines,  &c. 

Machines  employed  in  the  ma- 
nufacturing arts  are  named  accord- 
ing to  their  products,  as  lace-ma- 
chinery, rope-machinery,  paper- 
machines  ;  or  to  the  processes  they 
perform,    as    spinning- machinery, 

,  printing  -  machinery,  sawing  -  ma- 
chinery, &c. 

The  materials  of  which  machine- 
ry is  composed  are,  wood  of  various 
kinds,  iron,  brass,  copper,  and 
other  metals,  with  fiexible  materials 
for  bands,  cords,  &c.,  as  wool, 
caoutchouc,  and  leather. 

The  several  parts  of  machinery 
are,  frames,  plummer-blocks,  car- 
riages, bolts  and  nuts,  pins,  shafts, 
wheels,  pinions,  levers,  cranks, 
springs,  screws,  pulleys,  riggers, 
bands  or  belts,  and  cords,  &c., 
studs,  tappets,  wedges,  rods,  cylin- 
ders, tubes,  pistons,  valves,  buckets, 
fioats,  weights,  beams,  racks,  chains, 
clutches,  winches,  &c. 

The  power  of  engines,  as  distin- 
guished from  machines,  depends 
upon  the  nature  of  the  material 

~m 


MAC 

from  which  their  power  is  gathered. 
The  mere  mechanical  effect  of  every 
piece  of  machinery  is  calculable 
upon  its  combinations  of  certain 
elementary  forms,  commonly  term- 
ed the  mechanical  powers,  with 
deductions  from  the  effect  of  these 
for  friction  between  the  parts,  for 
rigidity  of  parts  which  are  theore- 
tically supposed  to  be  perfectly 
flexible,  and  for  the  elasticity  of 
parts  which  are  supposed  to  be 
perfectly  rigid. 

The  mechanical  powers,  some- 
times described  as  six  in  number, 
viz.  the  lever,  the  wheel  and  axle, 
the  pulley,  the  inclined  plane,  the 
wedge,  and  the  screw,  are  reduci- 
ble to  two  only,  viz.  the  lever  and 
the  inclined  plane,  in  each  of  which 
the  effect  produced  is  just  as  many 
times  greater  than  the  power  em- 
ployed, as  the  space  through  which 
the  power  moves  is  greater  than 
the  space  through  which  the  effect 
is  continued.  Thus,  if  with  a  lever 
a  weight  be  raised  ten  times  greater 
than  the  weight  or  power  by  which 
it  is  raised,  this  weight  or  power 
will  have  to  move  through  ten 
times  as  much  space  as  the  height 
through  which  tiie  greater  weight 
is  raised. 

Propriety  of  form  in  the  detail 
of  machinery  depends  upon  two 
circumstances.  The  first  is,  that 
the  parts  subject  to  wear  and  tear, 
and  influenced  by  strains,  should  be 
capable  of  motion  or  adjustment : 
the  second,  that  every  portion 
should  be  equally  strong,  and  pre- 
sent to  the  eye  a  uniform  figure, 
or  one  that  is  consistent  with  its 
degree  of  action :  theory,  practice, 
and  taste,  all  must  combine  to 
produce  such.  A  great  extent 
of  beauty  is  attainable  in  all  the 
details,  but  mathematical  reasons 
cannot  be  given  why  a  certain 
arrangement  of  lines  should  be 
preferable    to    another,   provided  I 


MAC 


MANDRIL. 


MAN 


they  are  equally  strong.  Truth 
does  not  strike  us  ^thout  the  as- 
sistance of  custom ;  but  so  great  is 
the  force  of  custom,  that  unassisted 
by  truth  it  has  worked  the  great- 
est miracles ;  and  it  certainly  must 
be  this  universal  Mentor  which 
gives  us  the  power  to  choose  be- 
tween forms. 

MaeeUumf  a  market-plaoe  for  all  kinds 
of  provisions 

Maeeriot  a  rough  wall 

Machicolations,  openings  formed  for 
the  purpose  of  defence  at  the  top 
of  castles  and  fortificationsi  by  set- 
ting the  parapet  out  on  corbels,  so 
as  to  project  beyond  the  face  of  the 
wall 

Madder  earmxM,  or  FiMs  carmine^ 
is,  as  its  name  expresses,  prepared 
from  madder.  It  differs  from  the 
rose  lakes  of  madder  principally  in 
texture,  and  in  the  greater  rich- 
ness, depth,  and  transparency  of  its 
colour,  which  is  of  various  hues, 
from  rose  colour  to  crimson 

Madder  orange,  or  Orange  lake,  is  a 
madder  lake  of  an  orange  hue,  va- 
rying from  yellow  to  rose  colour 
and  brovm 

Madder  purple.  Purple  rubiate,  or 
Field's  purple,  is  a  very  rich  and 
deep  carmine,  prepared  from  mad- 
der. Though  not  a  brilliant  pur- 
ple, its  richness,  durability,  trans- 
parency, and  superiority  o^  colour, 
have  given  it  the  preference  to  the 
purple  of  gold  purple,  and  to  burnt 
carmine. 

Madder  yellow  is  a  preparation  from 
the  madder  root.  The  best  is  of  a 
bright  colour,  resembling  Indian 
yellow,  but  more  powerful  and 
transparent,  though  hardly  equal 
to  it  in  durability  of  hue ;  metallic, 
terrene,  and  aUcaline  substances 
acting  on  and  reddening  it  as  they 
do  gamboge :  even  alone,  it  has  by 
time  a  natural  tendency  to  change 
in  appearance. 

Maniana,  seats  in  the  upper  porticoes 
of  the  Roman  forum,  from  whence 
spectators  witnessed  the  combats 
of  gladiators 

271 


Magnase  black  is  the  best  of  all 
blacks  for  drying  in  oil  without  ad- 
dition, or  preparation  of  the  oil : 
it  is  a  colour  of  vast  body  and 
tingeing  power 

Mahogany  is  a  native  of  the  West 
Indies  and  the  country  round  the 
Bay  of  Honduras.  It  is  said  to  be 
of  rapid  growth,  and  so  lai^  that 
its  trunk  often  exceeds  40  feet  in 
length  and  6  feet  in  diameter. 
Spanish  mahogany  is  importedfrom 
Cuba,  Jamaica,  Hispaniola,  St.  Do- 
mingo, and  some  other  of  the  West 
India  Islands,  in  logs  from  about 
20  to  26  inches  square  and  10  feet 
long.  It  is  close-grained  and  hard. 
There  is  also  African  mahogany.. 
All  the  species  are  used  for  many 
purposes,  more  particularly  for  su- 
perior household  furniture. 

Main  links,  the  links  in  the  parallel 
motion  which  connect  the  piston- 
rod  to  the  beam  of  a  steam  engine 

Malleable,  in  metallurgy,  capable  of 
being  spread  by  heating  or  by 
rolling, — a  distinguishing  character 
of  metals,  but  more  especially  of 
gold.  When  flattened,  it  is  said  to 
be  laminable ;  when  drawn  as  wire, 
ductile. 

Manacaybo  is  a  furniture  wood  of 
moderate  size,  hard,  as  good  as  ma- 
hogany, and  in  appearance  between 
that  and  tulip  wood 

Manchineel,  a  large  tree  of  the  West 
Indies  and  South  America :  it 
possesses  the  general  character  of 
mahogany,  but  has  a  poisonous  and 
unwholesome  sap 

Mandril,  the  spindle  which  carries 
the  centre-chuck  of  a  lathe,  and 
communicates  motion  to  the  m^tal 
to  be  turned :  in  small  lathes  it  is 
driven  by  a  pulley 

MandrU-frame,  the  head-stocks  or 
frame  bolted  to  the  end  of  a  lathe- 
bed,  for  the  purpose  of  supporting 
the  mandril 

Mangrove,  an  aquatic  tree,  straight- 
grained,  hard,  and  elastic:  much 
used  for  ship-building 

Man-hole,  in  locomotive  engines,  an 
opening  in  the  top  of  a  boiler,  used 


I 


MAN 


MARINE  ENGINE. 


MAR 


as  an  entrance  when  the  boiler  re- 
quires cleaning :  it  is  covered  by  a 
strong  plate  bolted  to  the  boiler 
plating,  so  as  to  be  steam-tight 

Max^hoU  covert  inlocomotive  engines, 
a  strong  plate  of  iron,  bolted  over 
the  man-hole  so  as  to  be  remove- 
able  when  required 

Manipulation^  in  mining,  the  manner 
of  digging  silver  or  other  metals ; 
a  term  now  generally  applied  to 
the  means  by  which  materials  or 
effects  are  produced 

Manner  is  that  habitude  which  paint- 
ers have  acquired,  not  only  in  the 
management  of  the  pencil,  but  also 
in  the  principal  parts  of  painting, 
— invention,  design,  and  colouring. 
It  is  by  the  manner  in  painting  that 
a  picture  is  judged  to  be  by  the 
hand  of  Titian,  Tintoret,  Guido,  the 
Caracci,  and  others.  Some  masters 
have  had  a  variety  in  their  manners 
at  different  periods  of  life,  and 
others  have  so  constantly  adttiered 
to  one  manner,  that  those  who  have 
seen  even  a  few  of  them  will  imme- 
diately know  them,  and  judge  of 
them  without  any  risk  of  a  mistake. 
The  variety  observable  among  ar- 
tists in  their  manner  and  taste 
arises  from  the  practice  of  the  dif- 
ferent schools  in  which  they  have 
received  their  instruction,  or  of  the 
artists  under  whom  they  have  stu- 
died. Yet  there  are  many  instances 
of  great  artists  who  have  divested 
themselves  of  that  early  partiality 
to  a  peculiar  manner,  and  have 
altered  it  so  effectually  as  to  fix  on 
one  abundantly  more  refined  and 
better  adapted  to  their  peculiar 
genius,  by  which  means  they  have 
arrived  at  excellence.  Thus,  for 
instance,  Raphael  proceeded,  and 
acquired  a  much  more  elevated 
manner  after  he  had  quitted  the 
school  of  Perugino. 

Manneristt  a  term  applicable  to  a 
painter  whose  pictures  have  no  re- 
semblance to  the  beautiful  varieties 
of  nature,but  discover  an  unpleasing 
and  tasteless  sameness 

Manometer^  an  instrument  intended 

272 


to  measure  the  rarefaction  and  con- 
densation of  elastic  fluids  in  confined 
circumstances,  whether  occasioDed 
by  variation  of  temperature  or  by 
actual  destruction,  or  generation  of 
portions  of  elastic  fluids 

Mantard  roqf,  of  French  origin,  from 
the  name  of  the  inventor ;  a  curb 
roof 

Manae,  a  parsonage-house 

Mantel-piece^  a  beam  across  the  open- 
ing  of  a  fire-place,  serving  as  a 
lintel  or  bressummer  to  support 
the  masonry  above,  which  is  called 
the  chimney-breast 

Maple  VDOod  is  considered  to  be  allied 
to  the  sycamore  or  the  plane- 
tree;  its  colour  is  pale:  much  used 
for  picture  frames  and  Tunbridge 
ware 

Marble,  a  kind  of  stone  found  in  great 
masses,  and  dug  out  of  pits  or 
quarries 

Marcus,  a  large  iron-headed  hammer 

Market,  The  market  or  forum  in  the 
cities  of  antiquity  was  different 
from  the  market  in  our  English 
towns,  where  flesh  meat,  merchan- 
dise, &c.,  are  usually  sold.  The 
Apostle  Paul  disputed  with  philo- 
sophers in  the  market  at  Athens: 
this  and  other  evidences  prove  it 
to  have  been  also  a  place  of  dispu- 
tation and  public  resort. 

Margin  or  Loek^rail,  the  flat  part  of 
the  stile  and  rail  of  framed  work 

Marine  engine,  a  steam  engine  to 
propel  a  ship.  There  are  various 
kinds  of  them,  the  beam,  direct- 
acting,  oscillating,  &c.  (See  Tred- 
gold's  work.) 

Marline,  a  small  line  used  for  winding 
round  ropes  and  cables 

Marone  is  of  a  dass  of  impure  colours, 
composed  of  black  and  red,  black 
and  purple,  or  black  and  russet 
pigments,  or  with  black  and  any 
other  denomination  of  pigments  in 
which  red  predominates 

Marone  lake  is  a  preparation  of  mad- 
der, of  great  depth,  transparency, 
and  durability  of  colour :  it  works 
well  in  water,  glazes  and  dries  in 
oil,  and  is  in  all  respects  a  good 


MAR 


MASONRY. 


MAT 


pigment :  its  hues  are  easily  given 
-with  other  pigments,  but  it  is  not 
much  used 

Marquetry,  chequered  or  inlaid  work; 
work  inlaid  with  variegation,  a  sort 
of  veneering,  representing  flowers, 
birds,  and  other  figures 

Miuonry.  The  early  Roman  archi- 
tecture,  both  in  public  and  private 
buildings,  was  of  far  more  durable 
materials  and  of  more  accurate 
masonry  than  such  as  was  executed 
in  the  decline  of  the  empire.  It 
began  to  be  uncemented  blocks  of 
stone,  passed  into  the  reticular  work 
of  the  republic,  thence  into  the 
travertine,  and  descended  into  the 
mixture  of  tufo,  and  brick,  and 
stucco  facing. 

Masonry.  Marble  is  polished  by  being 
first  rubbed  with  grit-stone,  after- 
wards with  pumice-stone,  and  lastly 
with  emery  or  calcined  tin.  Marbles, 
with  regard  to  their  contexture  and 
variegation  of  colour,  are  almost  in- 
finite :  some  are  black,  some  white, 
and  some  of  a  dove  colour :  the  best 
kind  of  white  marble  is  called 
statuary,  which,  when  cut  into  thin 
slices,  becomes  almost  transparent, 
which  property  the  other  kinds  do 
not  possess.  Other  species  of  mar- 
ble are  streaked  with  clouds  and 
veins.  The  texture  of  marble  is  not 
altogether  understood,  even  by  the 
best  workmen ;  but  they  generally 
know  upon  sight,  whether  it  wiU 
receive  a  poli£  or  not.  Some  mar- 
bles are  easily  wrought,  some  are 
very  hard,  other  kinds  resist  the 
tools  altogether.  Artificial  marble, 
or  Scagliola,  is  real  marble  pulver- 
ized and  mixed  with  plaster,  and  is 
used  in  columns,  basso-reUevos,  and 
other  ornaments. 

The  chief  kind  of  stone  used  in 
London  is  Portland  stone,  which 
comes  from  the  island  of  Portland, 
in  Dorsetshire ;  it  is  used  for  build- 
ings in  general,  as  strings,  window- 
sills,  balusters,  steps,  copings,  &c., 
but  under  great  weight  or  pressure 
it  is  apt  to  splinter,  or  flush  at  the 

joints.    When  it  is  recently  qnar- 

- 

273 


ried,  it  is  soft  and  works  easily,  but 
acquire  great  hardness  in  course 
of  time.  St.  Paul's  cathedral  and 
Westminster  bridge  are  construct- 
ed of  Portland  stone. 

Purbeck  stone  comes  from  an 
island  of  the  same  name,  also  in 
Dorsetshire,  and  is  mostly  employed . 
in  rough  work,  as  steps  and  paving. 
Yorkshire  stone  is  also  used 
where  strength  and  durability  are 
requisites,  as  in  paving  and  coping. 
Ryegate  stone  is  used  for  hearths, 
slabs,  and  covings. 

Mortar  is  used  by  masons  in  ce- 
menting their  works.  (See  Bricks 
laying^  Cements^  Mortars,  &c.)  In 
setting  marble  or  fine  work,  plaster 
of  Paris  is  used,  and  in  water-works, 
tarras  is  employed. 

Tarras  is  a  coarse  mortar,  durable 
in  water,  and  in  most  situations. 
Dutch  tarras  is  made  of  a  soft  rock- 
stone,  found  near  Cologne,  on  the 
Rhine.  It  is  burnt  like  lime,  and 
reduced  to  powder  by  mills,  from 
thence  carried  to  Holland,  whence 
it  has  acquired  the  name  of  Dutch 
tarras.  It  is  very  dear,  on  account 
of  the  great  demand  for  it  in  the 
construction  of  aquatic  works. 

An  artificial  tarras  is  formed  of 
two  parts  of  lime  and  one  of  plaster 
of  Paris:  another  sort  consists  of 
one  part  of  lime  and  two  parts  of 
well-sifted  coal  ashes. 

Mast  carUngSf  in  ship-building,  large 
timbers  at  the  side  of  the  mast 
rooms  that  are  left  deep  enough  to 
receive  the  cross-chocks 

Mastic,  a  cement  used  for  the  plaster- 
ing of  walls 

Mastic  varnish  is  easily  prepared  by 
digesting  in  a  bottle,  during  a  few 
hours,  in  a  warm  place,  one  part  of 
dry  picked  resin  with  two  parts  or 
more  of  the  oil  of  turpentine 

Materiatio,  according  to  Vitruvius, 
the  timber-work  of  a  roof 

Mathematics,  a  science  which  teaches 
to  number  and  measure  whatever 
is  capable  of  it,  comprised  under 
lines,  numbers,  superficies,  or  soUds 

Matter  and  Motion,    Quantities  of 


MAU 


MEASUREMENT. 


MEA 


matter  in  all  bodies  are  in  the  com- 
pound ratio  of  their  mag^iitude  and 
densities ;  for  if  the  magnitudes  are 
equal,  the  quantities  of  matter  will 
be  as  the  densities ;  and  if  the  den- 
sities are  equal,  the  quantities  of 
matter  will  be  as  the  magnitudes : 
therefore,  the  quantities  of  matter 
are  uniyersally  in  the  compound 
ratio  of  both. 

Mausoleum,  a  pompous  funereal  mo- 
nument, a  costly  sepulchre 

Mtunmum  and  mnUmum.  The  ex- 
tremes of  temperature  are  no  less 
important  to  the  meteorologist  than 
interesting  to  the  general  observer. 
They  are  obtained  by  the  self-re- 
gistering thermometer.  The  first 
instrument  of  this  kind  was  sug- 
gested by  John  Bemouilly.  Several 
fonns  of  thermometers  were  com- 
municated to  the  Royal  Society  by 
Lord  Charles  Cavenddsh.  The  next 
in  point  of  time  were  the  contri- 
vances of  Fitzgerald  and  Crighton. 
Six,  Rutherford,  Keith,  Bhickadder, 
and  Dr.  Trail,  greatly  added  to  the 

Fig. 


Stock  of  self-registering  thermo- 
meters. There  are  two  kinds  in 
general  use ;  Mr.  Six's,  which  is 
placed  vertically,  and  Dr.  Ruther- 
ford's, which  is  suspended  horizon- 
tally. The  latter  is  preferable  on 
land,  and,  £rom  its  simpUcity,  has 
to  a  certain  extent  superseded  the 
former. 

Mear,  thirty-two  yards  of  ground  in 
a  vein  of  ore 

Meaturement  of  earth-work.  There 
are  many  works  and  tables  pub- 
lished to  facilitate  the  admeasure- 
ment of  earth-work,  which  may  be 
reduced  in  practice  to  the  follow- 
ing geometrical  forms,  in  one  or 
more  chains  in  length,  as  the  case 
may  be.  The  two  chains  marked 
B  and  c  in  the  section  will  reduce 
to  the  forms  in  the  diagrams  that 
follow.  The  dotted  lines,  fig.  1, 
show  the  section  at  the  largest  end, 
next  to  B  in  the  section ;  and  the 
dotted  line,  fig.  2.  shows  the  sec- 
tion at  the  smallest  end,  next  to  a 
in  the  section. 

1. 


The  bottom  piece,  c,  being  re- 
duced to  a  parallel  throughout,  is 
measured  by  multiplying  the  area  of 

Slopes  S  to  1. 


the  end  by  the  length:  the  two 
banks  being  equal,  it  will  measure 
thus :  15'  0"  X  57'  0"  x  132'  0". 

274  ' 


The  piece  b,  the  middle  or  wedge 
piece,  being  parallel  horizontally 
only,  is  measured  by  taking  one- 
Fig.  2. 


Slopes  s  to  1. 


half  the    vertical  height :    thus, 
3'  6"  X  87'  0"  X  132'  0". 


MEA 


MEASUREMENT. 


MEA 


The  two  pieces  b  b  form  the  two 
halves  of  a  right-angled  pyramid, 
and  are  measured  hy  multiplying 
the  area  of  the  end  hy  one-third 
the  height :  therefore  T  0"  x  14'  0", 
the  slope  heing  2  to  1,  is  equal  to 
98'  0" ;  the  area  of  the  two  hases 
then,  1'  0"  X  98'  0"  x  44'  0",  gives 
the  cube  quantity  in  the  two. 
Me€uurement  qfsMppingfor  tonnage 
(called  the  *new  measurement') 
was  regulated  in  the  5th  and  6th 
of  George  lY.  By  this  Act  certain 
rules  were  established  for  ascer- 
taining the  tonnage  of  ships,  as 
well  on  shore  as  afloat,  and  of  ves- 
sels propelled  by  steam;  and  the 
account  of  such  tonnage,  whenever 
the  same  shall  have  been  ascer- 
tained according  to  the  rules  herein 
prescribed,  (except  in  the  case  of 
ships  admeasured  afloat,)  it  is  en- 
acted, shall  be  deemed  the  tonnage 
of  such  ships,  and  shall  be  repeated 
in  every  subsequent  registry  of 
such  ships,  unless  any  iteration 
shall  have  been  made  in  their  form 
and  burthen,  or  unless  it  be  disco- 
vered that  the  tonnage  had  been 
erroneously  computed:  and  it  is 
considered  that  the  capacity  of  a 
ship  is  the  fairest  standard  by  which 
to  regulate  its  tonnage ;  that  inter- 
nal measurements  will  afford  the 
most  accurate  and  convenient  me- 
thod of  ascertaining  that  capacity, 
and  that  the  adoption  of  such  a 
mode  of  admeasurement  will  tend 
to  the  interests  of  the  ship-builder 
and  the  owner. 

It  was  enacted  that  the  tonnage 
of  every  ship  or  vessel  required  by 
law  to  be  registered  shall,  previous 
to  her  being  registered,  be  mea- 
sured and  ascertained  while  her 
hold  is  clear,  and  according  to  the 
following  rule :  Divide  the  length 
of  the  upper  deck  between  the 
after-part  of  the  stem  and  the  fore- 
part of  the  stem-post  into  six  equal 
parts.  Depths :  At  the  foremost, 
the  middle,  and  the  aftermost  of 
those  points  of  division,  measure  in 

feet  and  decimal  parts  of  a  foot  the 
_ 


depths  from  the  under  side  of  the 
upper  deck  to  the  ceiling  at  the 
limber  strake.  In  the  case  of  a 
break  in  the  upper  deck,  the  depths 
are  to  be  measured  from  a  line 
stretched  in  a  continuation  of  the 
deck.  Breadths:  Divide  each  of 
those  three  depths  into  five  equal 
parts,  and  measure  the  inside 
breadths  at  the  following  points: 
at  one-fifth  and  at  four-fifths  from 
the  upper  deck  of  the  foremost  and 
aftermost  depths,  and  at  two-fifths 
and  four-fifths  from  the  upper  deck 
of  the  midship  depth.  Length : 
At  half  the  midship  depth  measure 
the  length  of  the  vessel  from  the 
after-part  of  the  stem  to  the  fore- 
part of  the  stem-post,  then  to 
twice  the  midship  depth  add  the 
foremost  ai^d  the  aftermost  depths 
for  the  sum  of  the  depths ;  add  to- 
gether the  upper  and  lowerbreadths 
at  the  foremost  division,  three  times 
the  upper  breadth  and  the  lower 
breadth  at  the  midship  division, 
and  the  upper  and  twice  the  lower 
breadth  at  the  after  division,  for 
the  sum  of  the  breadths;  then  mul- 
tiply the  sum  of  the  depths  by  the 
sum  of  the  breadths,  and  this  pro- 
duct by  the  length,  and  divide  the 
final  product  by  three  thousand  five 
hundred,  which  will  give  the  num- 
ber of  tons  for  register.  If  the 
vessel  have  a  poop  or  half-deck,  or 
a  break  in  the  upper  deck,  measure 
the  inside  mean  length,  breadth, 
and  height  of  such  part  thereof  as 
may  be  included  within  the  bulk- 
head; multiply  these  three  mea- 
surements together,  and  dividing 
the  product  by  92-4,  the  quotient 
will  be  the  number  of  tons  to  be 
added  to  the  result  as  above  found. 
In  order  to  ascertain  the  tonnage 
of  open  vessels,  the  depths  are  to 
be  measured  from  the  upper  edge 
of  the  upper  strake. 

To  ascertain  the  tonnage  of  steam 
vessels,  it  was  also  frirther  enacted, 
that  in  each  of  the  several  rules 
prescribed,  when  applied  for  the 
purpose  of  ascertaining  the  tonnage 


MEA 


MECHANICS. 


MBN 


of  any  ship  or  vessel  propelled  by 
steam,  the  tonnage  due  to  the  cu- 
bical contents  of  the  engine-room 
shall  be  deducted  from  the  total 
tonnage  of  the  vessel  as  determined 
by  the  rules,  and  the  remainder 
shall  be  deemed  the  true  register 
tonnage  of  the  said  ship  or  vessel. 
The  tonnage  due  to  the  cubical 
contents  of  the  engine-room  shall 
be  determined  in  the  following 
manner :  measure  the  inside  length 
of  the  engine-room  in  feet  and  de- 
cimal parts  of  a  foot  from  the  fore- 
most to  the  aftermost  bulk-head, 
then  multiply  the  said  length  by 
the  depth  of  the  ship  or  vessel  at 
the  midship  division,  as  aforesaid, 
and  the  product  by  the  inside 
breadth  at  the  same  division  at 
two-fifths  of  the  depth  from  the 
deck  taken  as  aforesaid,  and  divide 
the  last  product  by  92*4,  and  the 
quotient  is  deemed  the  tonnage 
due  to  the  cubical  contents  of  the 
engine-room. 
Measurement  of  standing  timber, — 
Measure  from  the  tree  ten,  twenty, 
thirty,  &c.,  feet,  and  then  plant  the 
theodolite  level:  direct  the  tele- 
scope to  the  bottom  of  the  tree, 
and  observe  the  degree  and  tenth 
of  depression;  and  to  the  top  of 
the  tree,  the  degree  and  tenth  of 
elevation.  When  the  timber  has 
been  previously  felled,  it  is  custo- 
mary, in  measuring,  to  girt  a  string 
round  the  middle  of  the  tree,  and 
fold  it  twice,  which  will  give  the 
fourth  part  of  the  girt,  and  which 
is  considered  the  true  side  of  the 
square;  then  the  length  Is  mea- 
sured from  the  but-end  of  the 
tree,  so  far  up  as  the  tree  will  hold 
half  a  foot  girt,  or,  more  properly 
speaking,  quarter-girt ;  that  is,  the 
line  six  inches  when  twice  folded. 
Various  tables  are  published,  to 
assist  the  timber-measurer  in  the 
performance  of  his  duty.  AU  tim- 
ber is  bought  and  sold  by  the  load, 
and  a  load  is  estimated  at  forty 
feet  of  unhewn  or  rough  timber, 
and  fifty  feet  of  hewn  timber,  which 


is  supposed  to  weigh  one  ton,  or 
twenty  hundred  weight. 

Mechanical  powers  are  contrivances 
by  which  we  are  enabled  to  sustain 
a  great  weight  or  overcome  a  great 
resistance  by  a  small  force.  (See 
Machinery.) 

Mechanics,  that  branch  of  practical 
science  which  considers  the  laws  of 
equilibrium  and  the  motion  of  solid 
bodies ;  the  forces  by  which  bodies, 
whether  animate  or  Inanimate,  may 
be  made  to  act  upon  one  another ; 
and  the  means  by  which  these 
forces  may  be  increased  so  as  to 
overcome  those  which  axe  more 
powerful.  The  term  mechanics 
was  originally  applied  to  the  doc- 
trine of  equilibrium.  It  is  now, 
however,  extended  to  the  motion 
and  equilibrium  of  all  bodies,  whe- 
ther solid,  fluid,  or  aeriform.  The 
complete  arrangement  of  mecha- 
nics is  now  made  to  embrace,  be- 
sides, the  pressure  and  tension  of 
cords,  the  equilibrated  polygon,  the 
catenary  curve,  suspension  bridges, 
the  equilibrium  of  arches  and  the 
stability  of  their  piers,  the  construc- 
tion of  oblique  arches,  the  equili- 
brium of  domes  and  vaults  with 
revetments,  the  strength  of  mate- 
rials, whether  they  be  of  wood  or 
iron,  dynamics,  or  the  science  of 
moving  bodies,  with  hydrostatics, 
pneumatics,  and  hydraulics. 

Medallion,  in  architecture,  any  cir- 
cular tablet  on  which  fig^ures  are 
embossed ;  busts,  &c. 

Mediaeval,  relating  to  the  middle  ages 

Member,  a  moulding;  either  as  a 
cornice  of  five  members,  or  a  base 
of  three  members,  and  applied  to 
the  subordinate  parts  of  a  building 

Mensuration  is  the  application  of  the 
science  of  arithmetic  to  geometry, 
by  which  we  are  enabled  to  discover 
the  magnitude  and  dimensions  of 
any  geometrical  figures,  whether 
solid  or  superficial.  To  enable  us 
to  express  this  magnitude  in  deter- 
minate terms,  it  is  necessary  to 
assume  some  magnitude  of  the 
same  kind  as  the  unit,  and  then,  by 


276 


END  OF  FART  II. 


MER 


MERE,  HAARLEMMER. 


MEI 


stating  how  many  times  the  given 
magnitude  contains  that  unit,  we 
obtain  its  measure. 

The  different  species  of  magni- 
tude  which  have  most  frequently 
to  be  determined  are  distinguish- 
able into  six  kinds,  viz.  1.  Length. 
— 2.  Surface. — 3.  Solidity,  or  ca- 
pacity .-^4.  Force  of  gravity,  com- 
monly called  weight. — 5.  Angles. 
—6.  'Time. 
Mere^  or  Meer^  a  name  frequently 
given,  in  England  and  the  Nether- 
lands, to  inland  lakes  or  sheets  of 
fresh  vrater,  such  as  Windermere, 
Whittleseamere,  Ugg-mere,  So- 
ham-mere,  in  England,  and  the 
Egmonder  meer,  Purmermeer,  and 
Haarlemmer  meer,  &c.,  in  the  Ne- 
therlands. The  term  is  most  fre- 
quently used  in  the  latter  country, 
where,  prior  to  1440,  there  were 
more  than  150  meers,  of  which  85 
occupied  an  area  of  177,832  acres, 
since  drained  and  reclaimed,  in  the 
provinces  of  North  and  South  Hol- 
land; and  where  also  the  Haarlem- 
mer meer,  covering  an  area  of 
45,230  acres,  is  now  in  course  of 
drainage. 

As  the  meers,  in  fen-lands,  serve 
as  reservoirs  to  hold  a  portion  of 
the  surplus  rain-water  falling  on 
the  district  of  which  they  form  a 
part,  their  being  dyked  off  and 
drained,  where  of  considerable  ex- 
tent,  has  most  important  effects  on 
the  neighbouring  lands,  by  con- 
tracting the  area  of  the  reservoir 
or  catch-water  basin  of  the  district. 
But  as  these  drainages  generally 
oblige  improvements  in  the  out- 
£dl8,  their  result  is  mostly  benefi- 
cial to  the  other  lands. 

The  beds  of  the  Dutch  meers 
are  from  10  to  20  feet  below  the 
level  of  the  lowest  point  of  the 
natural  outfall  in  their  districts; 
consequently  they  are  always 
drained  by  mechanical  means. 
Wind-milla  have  been  employed  to 
drain  the  land,  in  the  Netherlands, 
from  time  immemorial;  but  the 
drainage  of  the  meers  was  not  com- 

277  \ 


menced  until  1440,  about  whicl 
period  wind-mills  and  draining 
machinery  were  considerably  im- 
proved ;  and  as  late  as  1840,  wind 
mills  for  draining  purposes  conti- 
nued in  favour  with  the  Dutcb 
engineers,  in  preference  to  steam 
engines ;  and  at  that  date,  12,00G 
vrind-mills  were  employed  to  drain 
the  polders,  in  the  Netherhmds, 
and  only  five  small  steam  engines, 
the  largest  not  exceeding  SO-horsc 
power:  the  average  consumption 
of  fuel  was  20  lbs.  oi  coal  per  horse 
power  per  hour. 

In  the  English  fens,  steam  had 
in  a  great  measure  superseded  vrind- 
mills  for  drainage  purposes;  but 
the  consumption  of  fuel  was  nearly 
as  great  as  in  the  Dutch  engines. 

In  1839,  the  Dutch  States-Ge- 
neral  decreed  the  drainage  of  the 
Haarlenmier  meer,  and  voted  eight 
millions  of  florins  for  that  purpose, 
to  which  two  millions  more  were 
subsequently  added,  making  the 
total  sum  of  £  834,000. 

The  Haarlemmer  meer  forms 
part  of  the  great  drainage  district 
of  Rhynland,  which  has  an  area  of 
305,014  English  acres:  prior  to 
1848,  this  area  was  occupied  by 
56,609  acres  of  meers  and  water- 
courses, nearly  all  in  communica- 
tion with  each  other,  forming  what 
is  called  the  boezem^  or  catch-water 
basin  of  the  district ;  the  surface  of 
the  water  being  maintained  at  the 
lowest  level  of  natural  sluiceage, 
by  sluices  at  Katwyk  into  the  North 
Sea,  and  at  Spamdam  and  Halfweg 
into  the  T,  or  the  southern  end  of 
the  Zuyder  Zee. 

Above  the  boezem  are  75,357 
acres  drained  into  it  by  natural 
level;  and  at  depths  from  2  feet  6 
inches  to  4  feet  below  it  are  170 
polders  covering  an  area  of  135,850 
acres;  and  37,198  acres,  divided 
into  28  polders  which  were  for- 
merly meers,  but  are  now  drained, 
and  whose  beds  are  on  an  average 
14  ft.  below  the  level  of  the  boezem. 

The  surplus  ndn  and  infiltration 


MER 


MERE,  HAARLEMMER. 


MER 


waters  from  the  173,048  acres  of 
polder-land  are  lifted  into  the  boe- 
zem  by  the  united  action  of  261  large 
wind-mills,  with  an  average  force 
of  1500-hor8e  power. 

The  drainage  of  the  Haarlemmer 
meer,  which  forms  part  of  the 
boezem  or  basin,  will  deduct45,230 
acres  from  its  area,  and  redace  it 
to  11,379  acres,  or  ^th  part  of  its 
former  size ;  whilst  the  land  surface 
drained  into  it  will  be  increased 
from  229,657  to  293,735  acres. 

The  average  level  of  the  boezem 
is  10  inches  below  the  ordinary 
low  water,  and  27  inches  below 
high-wator  mark  in  the  Y  or  Zuy- 
der  Zee ;  and  7  inches  above  low 
water,  and  57  inches  below  ordi- 
nary high  water,  in  the  North  Sea. 
The  bed  of  the  Haarlem  Lake  is 
14  feet  below  the  winter  level  of 
the  boezem;  and  when  drained, 
the  maximum  lift  will  be  16  feet 
6  inches  to  17  feet,  according  to* 
the  state  of  the  Vfindt  which  raises 
or  depresses  the  surface  of  the  wa- 
ter in  the  canals  very  considerably. 
The  water  contents  of  the  Haar- 
lemmer meer  to  be  pumped  out, 
including  the  additional  quantity 
arising  from  the  surplus  rain  and 
infiltration  during  the  draining,  are 
estimated  at  800,000,000  cubic 
metres  or  tons. 

The  greatest  quantity  of  monthly 
drainage  when  the  meer  is  pumped 
out  is  estimated  at  36,000,000 
tons,  and  the  annual  average  sur- 
plus of  rain-water,&c.at54,000,000 
tons  to  be  Ufted,  on  an  average,  16 
feet  high. 

The  Dutch  engineers  were  gene- 
rally in  favour  of  wind-mills,  or  a 
combination  of  wind-mills  and 
steam  engines,  for  pumping  out 
the  meer;  but  in  1841,  the  late 
king,  WilUam  II.,  by  the  advice  of 
a  conmiiBsion,  decreed  that  steam 
engines  only  should  be  employed 
for  the  purpose ;  and  in  1842,  at 
the  suggestion  of  two  English  en- 
gineers, Mr.  Arthm*  Dean  and  Mr. 
Joseph  Gibbs,it  was  determined  to 

278 


erect,  and  they  were  directed  to 
prepare  the  designs  for,  three  steam 
engines  upon  the  high-presaure, 
expansive,  condensing  principle,  of 
the  ordinary  force  of  350-horse 
power  each,  but  capable  of  being 
worked  on  emergencies  up  to  500- 
horse  power. 

The  consumption  of  fuel  was 
limited  to  2^  lbs.  of  6oal  per  horse 
power  per  hour. 

The  three  engines  were  named 
the  '  Leeghwater,' '  Cruquiua,'  and 

*  Lynden,'  after  three  celebratedmen 
who  had  at  different  periods  pro- 
posed plans  for  draining  the  Haar- 
lemmer meer. 

The  *  Leeghwater '  was  the  first 
erected,  to  work  elev^i  pumps  of 
63  inches  diameter,  with  10-feet 
stroke  in  pumps  and  steam  cylin- 
ders; and  the  *  Cruquius '  and  'Lyn- 
den,'  were  afterwards  constructed, 
to  work  eight  pumps  each,  of  73  in. 
diameter,  and  with  10-feet  stroke; 
each  engine  is  calculated  to  lift 
66  cubic  m^res  or  tons  of  water 
per  stroke. 

The  accompanying  sketch  is  a 
representation  of  the  interior  of 
the  *  Lynden '  engine  and  engine- 
house,  on  the  upper  floor:    the 

*  Cruquius '  is  on  the  same  model ; 
but  the  *  Leeghwater '  has  the  inner 
ends  of  its  eleven  pump-beams  ar- 
ranged under  the  great  cross-head, 
instead  of  over  it. 

Each  engine  has  two  steam  cy- 
linders, placed  concentrically,  the 
one  within  the  other,  the  outer  of 
12  feet  diameter,  and  the  inner 
one  of  7  feet  diameter :  both  are 
secured  to  one  bottom,  and  covered 
by  one  cover,  but  the  inner  cyUn- 
der  does  not  touch  the  cover 
within  H  inch:  there  are  two 
pistons,  26  inches  deep,  the  com- 
partments of  which  are  fitted  with 
cast-iron  plates:  the  outer  piston 
is  annular,  and  has  a  packing  on 
both  sides:  beneath  this  annular 
piston  a  constant  vacuum  is  main- 
tained when  working:  the  two 
pistons  are  connected  by  five  pis- 


ynifoAt,  ts  Bhown  in  The  aketch,    I 
]  a  great  cross-head  or  cap,  the 
irfaolo  mass  weigliiog  about  Sb  tons,    ' 
■ndbyeightcQDiiecting-rodathecap 


pistons  ore  suspeuded  fiuiu  the  in 
ntr  ends  of  eight  cast-iron  halaticR 
bcBins,  10  the  outer  ends  ofwhiel 
are  hmig  the  eight  puiup.piat 


MER 


MERE,  HAARLEMMER. 


MER 


the  action  of  the  engines  is  therefore 
yery  simple:  the  steam  being  ap- 
plied under  the  inner  piston,  lifts 
both  the  pistons,  the  great  cross- 
head,  and  inner  ends  of  pump  ba- 
lance-beams simultaneously,  and  the 
pump-pistons  descend  at  the  same 
time:  by  an  hydraulic  apparatus 
attached  to  the  great  cross-head, 
the  dead  weight  of  the  pistons,  &c. 
is  arrested  at  the  point  to  which  it 
has  been  thrown  up  by  the  steam, 
and  time  is  given  for  the  Talves  of 
the  pump-pistons  to  close  before 
the  down -stroke  of  the  steam- 
pistons  is  made ;  then,  the  equili- 
brimp-valye  being  opened,  the  hy- 
draulic apparatus  is  liberated  at 
the  same  moment,  and  the  steam 
passing  from  beneath  the  small 
piston,  above  both  pistons,  the 
pressure  on  both  sides  of  the  small 
one  is  equalized,  whilst  nearly  two- 
thirds  of  the  steam  acts  upon  the 
annular  piston  against  a  vacuum, 
and  in  aid  of  the  dead  weight 
helps  to  make  the  down-stroke  in 
the  steam-cylinder,  and  the  up- 
stroke  in  the  pumps.  The  use  of 
the  two  cylinders  enables  the  en- 
gine-man, by  judiciously  altering 
tiie  expansion  in  the  small  cylinder, 
to  command  his  work  at  all  times, 
without  stopping  the  engine  to 
take  out,  or  put  in,  dead  weight,  as 
would  be  necessary  for  a  single- 
acting  one-cylinder  engine,  where 
dead  weight  only  is  used  for  lifting 
the  water.  It  has  frequently  oc- 
curred that  the  load  of  an  engine 
has  been  added  to  or  diminished 
by  10  or  12  tons  in  the  course  of 
half  an  hour,  by  the  action  of  gales 
of  wind  on  the  surface  of  the  meer 
and  boezem.  Each  engine  has 
two  air-pumps  of  40  in.  diameter, 
and  5-feet  stroke.  The  steam  is 
cut  off  in  the  small  cylinder  at 
from  one-fourth  to  two-thirds  of 
the  stroke,  according  to  the  load ; 
and  after  expanding  through  the 
remainder  of  the  stroke,  it  is  still 
further  expanded  in  the  large  cy- 
linder. 

280 


The  anticipated  economy  in  con- 
sumption of  fuel  has  been  realized : 
when  working  with  the  net  power 
of  350  horses,  the  average  con- 
sumption is  2^  lbs.  of  best  Welsh 
coals,  or  75  millions  duty  with 
94  lbs.  of  coal ;  and  on  a  late  trial, 
the  '  Cruquius '  and  '  Lynden '  en- 
gines were  found  to  do  a  duty  of 
87  millions. 

The  whole  cost  of  machinery, 
buildings, coals,  and  wages,  to  pump 
out  the  lake,  will  not  exceed 
iS  150,000,  whereas,  by  wind  it 
would  have  cost  £308,000,  being 
a  saving  of  £158,000;  and  there 
will  also  be  a  further  economy  upon 
the  works  in  the  bed  of  the  lake, 
amounting  to  JB  40,000  more,  so 
that  the  total  saving  by  steam  over 
wind  will  be  £  200,000,  and  three 
years'  time. 

To  compensate  the  district  of 
Rhynland  for  the  loss  of  45,230 
acres  of  the  boezem  or  catch-water 
basin,  a  steam  engine  of  200-horse 
power,  driving  10  large  scoop- 
wheels,  has  been  erected  at  Spam- 
dam  to  lift  the  boezem  water  over 
the  tide  in  the  Y,  or  base  of  the 
Zuyder  Zee,  where  the  rise  is  on 
an  average  only  17  inches.  This 
engine  has  discharged  30,000,000 
tons  of  water  in  fifteen  consecutive 
days.  When  the  state  of  the  boezem 
permits  the  * Leeghwater,'  'Cru- 
quius,' and*Lynden  'engines  towork 
freely,  they  discharge  on  an  aver- 
age 2,000,000  tons  in  twenty-four 
hours,  and  they  are  capable  of  doing 
this  down  to  their  fiUl  depth.  In 
the  month  of  June,  1849,  the  three 
engines  discharged  60,000,000  tons 
water,  and  lowered  the  meer  one 
foot ;  between  the  1st  of  May  and 
Ist  of  December  they  had  lowered 
the  lake  5  feet,  and  by  the  autumn 
of  1850,  it  is  calculated  the  dry 
land  will  appear.    (See  Table.) 

The'Leeghwater,'  *  Cruquius'  and 
'  Lynden '  engines  were*  contracted 
for  jointly  by  the  Hayle  and  Per- 
ran  Foundry  Companies,  Cornwall, 
and  were  manufactured  and  erected 


MERES,  DRAINAGE  OF. 

Table, 

arranged  chronologically,  showing  the  Lakes,  Meers,  and  Water-places 

which  have  been  drained  by  mechanical  means,  and  converted  into  Fertile 

iMnds,  in  the  Provincee  of  North  and  South  Holland,  in  the  Netherlands. 

• 

,  .  ,  _    —    — .  _                   .  ,                 

NORTH  HOLLAND. 

■sS 

SOUTH  HOLLAND. 

ti 

Date  of 

%\ 

Name  of  Lake, 

Name  of  Lake, 

Drain- 

Meer, or  Water- 

Location  near. 

gw 

Meer,  or  Water- 

liocation  near. 

Area 

in  El 

age. 

place. 

-<.g 

place. 

1440 

N«8ch  Meer 

Werverahoofd 

50 

1460 

Burgfaomder  Do. 

Burghom 

684 

1559 

The  Zyp 
Egmonder  Meer 

Schagerbrug 

19026 

1555 

Egmond 

10080 

f » 

Berger         Do. 
Dafll            Do. 

Bei^n 

1394 

1560 

Koedyk 

288 

1561 

Vrooner      Do. 

St.  Pancraa 

246 

1566 

Acbter        Do. 

78 

y« 

Kooi            Do. 

Do. 

33 

' 

1567 

Zwyxu         Do. 

Oudorp 

38 

1580 

Boekeler     Do. 

Akeraloot 

745 

1607 

Wog           Do. 

Spierdyk 

1541 

1608-12 

The  Beemiter 

Purmerend 

16369 

i* 

The  Weiring-  1 
erwaard         / 

Golkom 

3979 

1614 

. .        •  • 

«  •                •  ■ 

•  • 

Soetenneenche  \ 
Meer              / 

Soetermeer 

1285 

1616 

T^aarlingerMeer 

Warmenhttizen 

.   98 

1618-22 

Purmer       Do. 

Purmerend 

6260 

1628 

•  •                •  • 

.  .                   .  k 

•  ■ 

The  Litaerpoel 

Liase 

533 

1624 

Baarsdorper  Do. 

Berkhont 

401 

Hem  Meer 

Saaaenheim 

149 

TheEngeWor-1 
mer               J 

Near  Wonne-') 
meer              / 

241 

•f 

mrm^ 

1626 

The  Hr.  Hu-1 
gowaard        / 

Langendyk 

6904 

•• 

BroekerMeer  / 

Brock  &Wa-  \ 
ter-land         / 

638 

1625-28 

Belmer        Do. 

Monnikendam 

310 

ff 

Buikalooter  Do. 

BuikBloot 

772 

1626 

The  Groot  Waal 

Berkhout 

138 

ff 

Wormer  Meer 

Giap 

3786 

1626-29 

•  •               ■  • 

• .        . . 

•  ■ 

Diemer  Meer 

Oiemen 

1575 

1630 

Benning      Do. 

Abbekerk 

245 

»s 

Harger  &  Pet-  "l 
temer  Polder  J 

Petten 

987 

16S1 

The  Tien  Meeren 

Haring  Ganpel 

4647 

0§ 

The  Drie    Do. 

Oud  Ganpel 

730 

; 

Pf 

Kler  Meer 
Kerk  Do. 

Koedyk 

147 

^A 

Do. 

48 

PW 

Deble  Do. 

Warmenhuixen 

31 

GrebDo. 

Do. 

201 

M 

The  Vier         \ 
Meertjes        J 
Braak  Meer 

Medenblyk 
Eerstwoude 

680 
69 

■ 

Veenhuizer  Do. 

Veenhuizen 

718 

, 

FW 

Schals  Do. 

Knollendam 

145 

1632 

Schermer  Do. 

N.&  S.  Schermer 

12938 

1633 

The  Vier          "I 
Meerljes        / 

Obdam 

142 

1636 

Berk  Meer 

Veenhuizen 

596 

1640 

Kolk  Do.         { 

Lambert  Scha-*) 
gen                / 

■  ■                 •  • 

220 

1642 

• .        *• 

•  • 

Slooter  Meer 

199 

1643 

Star  Do. 

Oostgrafdyk 

1447 

1644 

NoordeinderDo. 

Graft 

409 

1645 

Sap  Do. 

TheRyp 

62 

1646 

•  •                 •  • 

• .        •  • 

•  • 

The  Wilde      ^ 
Veenen         J 

Moerkapel 

1322 

I6SO 

•  •                      a  ■ 

•  •        •  • 

•  • 

Stem  Meer 

Aalsmeer 

409 

281 


MERES,  DRAINAGE  OF. 

"5  S 

• 

•s  S 

NORTH  UOLLAHD—continued. 

_  c 

SOUTH  HOLLAND— continued. 

•0  bu 

Date  of 

Name  of  Lake, 

• 

Name  of  Lake, 

Drain- 

Meer, or  Water- 

liocation  near. 

Sh* 

Meer,  or  Water- 

Location  near. 

SH 

age. 

place. 

<.S 

place. 

^.S 

1666 

Wassenartche  \ 
Polder           / 

Rhynsaterwoude 

2488 

1668 

The  Driemansi 
Do.                / 

Soetermeer 

2013 

1674 

Horn  Meer 

Aalsmeer 

441 

1700 

Binnenweg-     1 
sclie  Polder  / 

Zegwaard 

2247 

}f 

H.  GecBt  Polder 

Leyniinden 

384 

1715 

Goger        Do. 

Alkemade 

607 

1727 

..  ' 

Katjes        Do. 

Zevenhutzen 

772 

1736 

The  8tarr«-      1 
vaartfl     Do.  / 

Stompwyk 

443 

1736-44 

The  Vier  Am-  \ 
bachts    Do.  / 

Esselykerwoude 

518 

1741 

Vrieskoophche  \ 
Do.                / 

Vriezekoop 

1325 

1754-62 

Rndragts  Do. 

Zevenhuizen 

2473 

1758-59 

Damhouder  Do. 

Stompwyk 

949 

} 759-65 

Novider  Plas 

Hazerswoude 

8415 

1760-62 

Palentern»she  \ 
Polder           / 

Zegwaard 

1279 

1763-68 

Ouwendyksche  \ 
&  Boe     Do.  / 

Esselykerwoude 

806 

1764 

Bovenkerker  Do. 
Great  and  Lit-*) 

Amstdyeen 

3412 

1767-68 

tie     Kalko-  \ 
vensche  Do.  J 

Oudshoom 

1318 

99 

The  Groote  Do. 

Soetermeer 

1686 

1768-71 

Do.            .Do. 

Stompwyk 

1178 

1772-77 

Berkelsche  Do. 

Berkel 

2171 

1772-82 

Bleiawyksche    "^ 
Drainage      / 

Bleiswyk 

8299 

I773-8O 

..         .. 

SchiebrokjBche  \ 
Polder           / 

Schiebroek 

1457 

1781-84 

Veender   en     \ 
Lyker   Do.   J 

Alkemade 

1373 

1782-89 

.. 

Pynakerscke  Do. 

Pyn acker 

1270 

1786-88 

Aarlander-        i 
veensche  Do.  / 

Aarlanderveen 

1171 

1788-91 

Zestienho-        *) 
vensche    Do.  / 

Overschie 

1064 

1788-99 

Schieveensche  \ 
Do.                 / 

Ovemchie 

654 

17901 
1810/ 

Mydrechtsche  \ 
Do.                J 

Mydrecht 

2622 

1  T/l^  ^ 

NiewekoopBche  1 

179/  \ 
1809J 

•            *  •                •  ■ 

en  Zevenho-  > 

Niewekoop 

1571 

venesche  Do.  j 

1798-99 

Gnephoek   en  ^ 
Vrowe      Do.  / 

Oudshoom 

254 

1/991 
1801  / 

Bieslandsche  Do. 

Nootdorp 

333 

1810 

Kleine  Slarre-I 
vuartsche  Do.  / 

Leydschendam 

23 

1820 

Bylmer  Meer 

Weesp 

1470 

1828-40 

The  Zuid  Pla« 

Rotterdam 

14820 

1842 

Nootdorpsche  \ 

Plas                / 

Haarlem  Lake  1 

Delft 
Amsterdam,     *] 

S500 

1840-50 

. . 

•    •               •   • 

(not  yet  com-  > 
pleted)           j 

Haarlem  and  • 
Leyden           j 

45230 

98557 

In  South  Holland,  acres    i 

124505 

In  North     Do.        Do. 

98557 

Total  Acres     ] 

123063 

282 


M£R 


MBRIDIAN. 


MES 


under  the  direction  of  Mr.  Arthur 
Dean ;  they  have  all  worked  during 
nearly  three  months  with  only 
twelve  hours'  stoppage. 

It  may  be  said  in  this  instance, 
the  Dutch  have  realized  the  fable 
of  the  *  Hare  and  the  Tortoise:' — 
in  1840y  the  erection  of  a  steam 
engine  of  30  or  40-horse  power, 
for  drainage  purposes,  was  thought 
to  be  a  bold  step,  whereas,  under 
the  guidance  of  English  engineers, 
they  have  dared,  between  1840  and 
1849,  to  erect  the  most  gigantic 
steam  machinery  in  the  world. 

The  low  lands  of  the  Nether- 
lands are  divided  into  large  drain- 
age districts,  which  have  been  em- 
banked against  the  inroads  of  the 
tides  and  river  floods ;  and  the  va- 
rious parts  of  a  district  are  con- 
nected by  what  is  called  the  boezenif 
or  water-basin,  or  reservoir,  formed 
by  the  rivers,  lakes,  meers,  or  water- 
places  having  their  origin  in  the 
district,  and  serves  to  receive  the 
water  drained  either  naturally  or 
artificially  from  the  surrounding 
lands.  The  boezem  is  put  into 
communication  with  the  exterior 
waters  of  the  rivers  or  sea  by  locks 
and  sluices.  All  lands  in  a  given 
drainage  district  above  the  level  of 
the  boezem,  and  draining  naturally 
into  it,  are  called  *  boezem  lands.' 
All  lands  lying  below  the  boezem, 
and  drained  into  it  by  machinery, 
are  called  polders.  Of  polders  there 
are  two  kinds :  the  first  are  seldom 
more  than  2  or  3  feet  below  the 
level  of  the  boezem,  which  is  em- 
banked above  the  natural  surface 
of  the  land:  of  such  polders  there 
are  upwards  of  1000  in  the  pro- 
vince of  South  Holland  only ;  and 
they  are  kept  dry  by  the  aid  of  an 
immense  number  of  wind-mills.  Of 
the  second  class  of  polders  there 
are  43  in  North  Holland  and  ^3  in 
South  Holland,  as  recorded  in  the 
preoedingTabIe,and  these  are  works 
of  a  formidable  character,  being,  for 
the  most  part,  the  beds  of  lakes,  or 
permanent  sheets  of  water,  varying 

283 


in  depth  from  5  to  20  feet  below 
the  boezem,  and  requiring  powerful 
machinery  to  pump  them  out  in 
the  first  instance,  and  to  maintain 
them  dry  afterwards ;  and  as  these 
lakes,  &c.,  always  form  part  of  the 
boezem,  or  reservoir,  of  a  much 
larger  tract  of  land,  their  drainage 
frequentlyinvolves  the  construction 
of  immense  works,  and  seriously 
affects  the  prosperity  of  the  whole 
district  in  which  they  are  situate. 
The  preceding  Table  will,  as  an 
apt  illustration  of  the  subject  of 
draining  large  districts,  be  found 
important  in  engineering  history. 

By  the  Table  it  vriU  be  seen  that 
the  North  Hollanders  had  effected 
the  drainage  of  nearly  all  their 
lakes,  &c.,  as  early  as  1645,  and 
they  had  then  recovered  98,557 
acres  of  land  forming  their  beds ; 
whereas  the  South  Hollanders  had 
in  1645  only  drained  five  small 
lakes,  whose  area  was  only  3741 
acres.  It  must  be  observed  that 
the  South  Holland  drainages  are  of 
a  much  more  extensive  character 
than  those  of  North  Holland,  and 
the  difficulties  to  be  overcome  were 
much  greater;  and  last,  but  not 
least,  the  North  Hollanders  were 
much  richer  than  their  neighbours. 
Of  the  223,000  acres  of  lakes,  &c., 
recorded  in  the  Table,  upwards  of , 
50,000  acres  were  formed  artifi- 
cially, by  dredging  the  peat  pulp 
to  the  depth  of  10  or  20  feet,  to 
serve  as  fuel  for  domestic  pur- 
poses, &c. 

Meridian,  in  astronomy,  the  line 
drawn  from  the  north  to  the  south, 
through  the  zenith,  nadir,  and  poles, 
which  line  the  sun  crosses  at  noon 

Merlon,  the  solid  part  of  an  embattled 
parapet,  standing  up  between  the 
embrasures 

Menu,  the  plain  surface  between  the 
channels  of  a  triglyph 

Mesaula,  a  passage,  gallery,  lobby; 
an  entry  or  court 

Mettling,  brass  ornaments;  candle- 
sticks ;  sacred  utensils  used  in  An- 
glo-Saxon times 


MET 


METALS. 


MET 


MetaUurgy,  the  art  of  working  me- 
tals, invented  by  Tubal-Cain,  b.  c. 
3608. "  And  Zillah  also  bare  Tubal- 
Cain,  an  instnictor  of  every  arti- 
ficer in  brass  and  iron."  {Gen.  iv. 
22.)  In  the  earUest  periods  of  his- 
tory, mention  is  made  of  the  ex- 
cellence in  working  metals  among 
the  Egyptians.  Some  specimens  of 
metal-work  of  an  early  date  exist, 
and  modem  fashion  has  also  pro- 
duced some  very  elaborate  ex- 
amples. 

MetaU  are  elementary  bodies  capable 
of  combining  with  oxygen;  and 
many  of  them,  during  this  combi- 
nation, exhibit  the  phenomenon  of 
combustion.  Seven  metals  only 
were  formerly  known ;  but  recently 
a  much  greater  number  has  been 
been  added.  Metals  are  distin- 
guished by  their  great  specific  gra- 
vity, considerable  tenacity,  and 
hardness,  opacity,  and  property  of 
reflecting  the  greater  part  of  the 
light  which  fiills  on  their  surface, 
giving  rise  to  metallic  lustre  or 
brilliancy.  Metals  are  the  best 
conductors  of  caloric :  their  expan- 
sibilities are  various,  and  are  pro- 
bably nearly  in  the  order  of  their 
fusibilities.  Mercury  melts  at  so 
low  a  temperature,  that  it  can  be 
obtained  in  the  solid  state  only  at 
a  very  low  temperature ;  others,  as 
platina,  can  scarcely  be  melted  by 
the  most  intense  heat  which  we 
can  excite. 

Metdl8  employed  m  the  mechanical 
arte: 

Antzmont  is  of  a  silvery  white 
colour,  brittle,  and  crystalline  in 
its  ordinary  texture:  it  fuses  at 
about  800° :  its  specific  gravity  is 
6-712. 

BisMDTH  is  a  brittle,  white 
metal,  with  a  slight  tint  of  red :  its 
specific  gravity  is  9*822 :  it  fuses 
at  476^  and  always  crystallizes  on 
cooling. 

Copper  is  the  only  metal,  with 
the  exception  of  titanium,  whichhas 
a  red  colour :  it  has  much  lustre, 
is  very  malleable  and  ductile,  and 

~284 


exhales  a  peculiar  smell  when 
warmed  or  rubbed :  it  melts  at  a 
bright  red  or  dull  white  heat,  or  at 
a  temperature  intermediatebetween 
the  fusing  points  of  silver  and  gold 
« 1996°  Fahr.  :  its  specific  gravity 
varies  from  8*86  to  8*89,— the  for- 
mer being  the  least  density  of  cast 
copper;  the  latter,  the  greatest  of 
roUed  or  hammered  copper. 

Gold  is  of  a  deep  and  peculiar 
yellow  colour :  it  melts  at  a  bright 
red  heat,  equivalent,  according  to 
Daniell,  to  2016°  Fahr.,  and  when 
in  fusion,  appears  of  a  brilliant 
greenish  colour:  its  specific  gra- 
vity is  19*3 :  it  is  so  malleable, 
that  it  may  be  extended  into  leaves 
which  do  not  exceed  the  ts^W?^^ 
of  an  inch  in  thickness,  or  a  single 
grain  may  be  extended  over  56 
square  inches  of  surface. 

Lead  in  colour  is  blueish  white: 
it  has  much  brilliancy,  is  remarka- 
bly flexible  and  soft,  and  leaves  a 
black  streak  on  paper.  When  han- 
dled, it  exhales  a  peculiar  odour : 
it  melts  at  about  612°,  and  by  the 
united  action  of  heat  and  air,  is 
readily  converted  into  an  oxide. 
Its  specific  gravity,  when  pure,  is 
11*445 ;  but  the  lead  of  commerce 
seldom  exceeds  11*35.  Lead  is 
used,  in  a  state  of  comparative 
purity,  for  roofs,  dstems,  pipes, 
vessels  for  sulphuric  acid,  &c. 

Mercury  is  a  brilliant  white 
metal,  having  much  of  the  colour 
of  silver.  It  has  been  known  from 
remote  ages.  It  is  liquid  at  com- 
mon temperatures,  solid  and  mal- 
leable at  —40°  Fahr.,  and  contracts 
considerably  at  the  moment  of  con- 
gelation :  it  boUs  and  becomes  va- 
pour at  about  670*^:  its  specific 
gravity  at  60°  is  13*5.  In  the  solid 
state,  its  density  exceeds  14.  The 
"specific  gravity  of  mercurial  vapour 
is  6*976. 

Nickel  is  a  white,  brilliant 
metal,  which  acts  upon  the  magne- 
tic needle,  and  is  itself  capable  of 
becoming  a  magnet.  Its  magnetism 
is  more  feeble  than  that  of  iron, 


MET 


METALS. 


MET 


and  vanishes  at  a  heat  somewhat 
below  redness.  At  6*30^  it  is  duc- 
tile and  malleable :  its  specific  gra- 
vity varies  from  8*27  to  8*40  when 
fused,  and  alter  hammering,  from 
8*69  to  9*00.  It  is  not  oxidized  by 
exposure  to  air  at  common  tempe- 
ratures;^ but  when  heated  in  the 
air,  it  acquires  various  tints,  like 
steel:  at  a  red  heat,  it  becomes 
coated  by  a  grey  oxide. 

PAI.I.ADIUM  is  of  a  dull  white 
colour,  malleable  and  ductile.  Its 
specific  gravity  is  about  11*3,  or 
11*86  when  laminated.  It  fuses  at 
a  temperature  above  that  required 
for  the  fusion  of  gold. 

Platinum  is  a  white  metal, 
extremely  difficult  of  fusion,  and 
unaltered  by  the  joint  action  of 
heat  and  air.  It  varies  in  den- 
sity frt)m  21  to  21*5,  according  to 
the  degree  of  mechanical  compres- 
sion it  has  sustained.  It  is  ex- 
tremely ductile,  but  cannot  be 
beaten  into  such  thin  leaves  as  gold 
and  silver. 

Rhodium,  discovered  in  1803 
by  Dr.  WoUaston,  is  a  white  metal, 
very  difficult  of  fusion.  Its  specific 
gravity  is  about  11 ;  it  is  extremely 
hard.  When  pure,  titie  acids  do  not 
dissolve  it. 

SiLYXR  is  of  a  more  perfect 
white  than  any  other  metal :  it  has 
considerable  brilliancy,  and  takes  a 
high  polish.  Its  specific  gravity 
varies  between  10*4,  which  is  the 
density  of  cast  silver,  and  10*5  to 
10*6,  which  is  the  density  of  rolled 
or  stamped  silver.  It  is  so  mallea- 
ble and  ductile,  that  it  may  be  ex- 
tended into  leaves  not  exceeding  a 
ten-thousandth  of  an  inch  in  thick- 
ness, and  drawn  into  wke  much 
finer  than  a  human  hair.  Silver 
melts  at  a  bright  red  heat,  estimated 
at  1873°  Fahr.,  and  when  in  fusion 
appears  extremely  brilliant. 

Tin  has  a  silvery  white  colour, 
with  a  slight  tint  of  yellow :  it  is 
malleable,  though  sparingly  ductile. 
Common  tin-foil,  which  is  obtained 
by  beating  out  the  metal,  is  not 


more  than  -nAnr^  ^^  '^  ^^  ^ 
thickness,  and  what  is  termed  <  white 
Dutch  metal'  is  in  much  thinner 
leaves.  Its  specific  gravity  fluctuates 
from  7*28  to  7*6,  the  highest  being 
the  purest  metaL  When  bent,  it 
occasions  a  peculiar  crackling  noise, 
arising  from  the  destruction  of  co- 
hesion amongst  its  particles.  When 
a  bar  of  tin  is  rapidly  bent  back- 
wards and  forwards  several  times 
successively,  it  becomes  so  hot  that 
it  cannot  be  held  in  the  hand. 
When  rubbed,  it  exhales  a  peculiar 
odour.  It  melts  at  442°,  and  by 
exposure  to  heat  and  air  is  gradu- 
ally converted  into  a  protoxide. 

Zinc  is  a  blueish  white  metal, 
with  considerable  lustre;  rather 
hard ;  of  a  specific  gravity  of  about 
6'8  in  its  usual  state;  but  when 
drawn  into  wire,  or  rolled  into 
plates,  its  density  is  augmented  to 
7  or  7*2.  In  its  ordinary  state,  at 
common  temperatures,  it  is  tough, 
and  with  difficulty  broken  by  blows 
of  the  hammer:  it  becomes  very 
brittle  when  its  temperature  ap- 
proaches that  of  fusion,  which  is 
about  773°;  but  at  a  temperature 
a  little  above  212°,  and  between 
that  and  300°,  it  becomes  ductile 
and  malleable,  and  may  be  rolled 
into  thin  leaves,  and  drawn  into 
moderately  fine  wire,  which,  how- 
ever, possesses  but  little  tenacity. 
When  a  mass  of  zinc  which  has 
been  fused  is  slowly  cooled,  its 
fracture  exhibits  a  lamellar  and 
prismatic  crystalline  texture.  The 
pipes  of  the  great  organ  in  the 
town-hall  at  Birmingham,  and  in 
that  of  York  cathedral,  are  made 
principally  of  sheet  zinc. 
Meteorology,  the  term  now  used  for 
the  purpose  of  designating  the  sci- 
ence which  observes,  registers,  clas- 
sifies, and  compares  the  various  and 
varying  phenomena  of  our  atmo- 
sphere. It  remarks,  at  the  same 
time,  the  connection  of  those  phe- 
nomena with  the  heavenly  bodies, 
and  with  the  solid  and  liquid  ma- 
terials of  the  earth,  in  reference  to 


285 


n5 


MET 


MILESTONES. 


MIL 


their  reciprocal  and  combined  in- 
fluence indetermining  the  character 
of  different  climates,  and  with  the 
view  of  learning  the  meteoric  his- 
tory of  every  region  of  our  globe, 
of  ultimately  investigating  the  laws 
of  atmospheric  change,  the  plan  of 
meteoric  action;  the  theory,  in  fact, 
of  meteorological  phenomena,  on 
which  depend  essentially  the  fit- 
ness of  the  various  portions  of  the 
earth's  surface  for  the  production 
of  distinct  vegetable  and  other  sub- 
stances, and  for  the  support  of  ani- 
mal life. 

Meteorological phenomenadixt  not  con- 
fined to  the  inferior  regions  of  the 
atmosphere,  but  extend  as  far  as 
observations  have  reached.  It  is 
possible  their  influence  may  extend 
universally,  and  therefore  it  is  de- 
sirable to  know  whether  there  exists 
throughout  space  a  medium,  or  con- 
ductor, or  whether  there  is  such  a 
thing  in  matter  as  vacuum.  Some 
have,  it  is  true,  endeavoured  to  re- 
concile opinions  so  diametrically 
opposed  toeacli  other,  by  suggesting 
that  the  universe,  though  infinite, 
is  a  plenum  and  a  void !  This  (the 
doctrine  of  Leucippus)  a  recent  au- 
thor declares  to  be  really  true; 
and  some  conceive  that  the  New- 
tonian theory  necessarily  implies 
the  reality  of  a  metaphysical  void, 
although  the  astronomical  calcula- 
tions of  that  theory  wero  made 
without  any  allowance  for  the  re- 
sistance to  the  motions  of  the 
planets,  which  might  beexperienced 
from  such  a  medium. 

Meioehef  the  intervals  between  two 
denticuli  in  the  Ionic  entablaturo 

Metopcy  the  spaces  between  the 
triglyphs  of  the  Doric  frieze,  which 
.  in  the  Parthenon,  for  instance,  were 
filled  in  with  sculpturo;  but  in 
modern  porticoes  that  are  taid  to 
be  after  the  Parthenon^  they  are 
mere  blanks 

Mkref  a  French  measure,  equal  to 
39*3702  English  inches. 

Me2zarunet  a  low  intermediate  story 
between  two  higher  ones 

~286 


Mezzo-relievOt  projection  of  figures 
between  alto-  and  basso-relievo; 
demi-relievo 

MezzotintOy  a  kind  of  engraving  nearly 
resembling  painting,  i  effected  by 
scraping  and  burnishing  the  copper 

Mezuzothf  a  name  given  to  certain 
pieces  of  parchment  which  were 
anciently  fixed  on  the  door-posts  of 
houses 

MicOt  an  important  ingredient  in  the 
composition  of  rocks,  consisting  of 
silica,  alumina,  oxide  of  iron,  and 
potash:  it  is  easily  divided  into 
laminae,  even  to  the  -^fnftnnt^^  V^ 
of  an  inch,  and  is  chstinguishable 
from  tale  by  its  elasticity :  in  Russia 
it  is  used  instead  of  window-glass 

Micrometer^  an  instrument  for  mea- 
suring small  spaces 

Microscope^  an  optical  instrument  for 
rendering  risible  minute  objects: 
the  tingle  microscope  has  one  lens 
only,  and  magnifies  by  permitting 
a  near  riew  of  the  object ;  in  the 
conyMund  microscope,  a  focal  image 
is  again  magnified  by  other  lenses 

MiddH-ground  is  a  term  used,  not  to 
express  the  middle  of  a  picture,  but 
generally  perspectively  so ; — some- 
times it  is  the  highest  part  of  a 
picture,  and  sometimes  the  second 
degree  of  shade.  Pictures  are  di- 
rided  into  three  parts :  fore-ground, 
middle-ground,  and  back-ground. 

Middle^railt  the  rail  of  a  door  which 
is  upon  a  level  with  the  hand  when 
hanging  freely :  the  lock  of  the  door 
is  gencarally  fixed  in  this  rail 

Mida^p  signifies  the  middle  of  a  ship 

Midak^'bendt  the  broadest  frame  in 
the  ship,  called  the  'dead-flat' 

MUeatonee,  Pliny  says,  the  miles  on 
the  Roman  roads  were  distinguished 
by  a  pillar,  or  a  stone,  set  up  at  the 
end  of  each  of  them,  and  which  was 
marked  with  one  or  more  figures, 
signifying  how  £sr  it  was  firom  the 
Milliarium  Aureum,  a  pillar  in  the 
forum  near  the  temple  of  Saturn, 
which  had  on  it  the  figure  I.,  so 
that  the  next  pillar  to  it,  which  was 
marked  II.,  was  but  one  mile  from 
thestandardpillar,and  consequently 


MIL 


MINES. 


MIN 


the  XIV.  and  XI.  stones  were  but 
thirteen  and  ten  miles  from  the 
forum. 

MiUenmum,  a  thousand  years;  the 
term  applied  to  that  period  of  the 
Christian  Church  described  in  Re- 
velation, during  which)  according  to 
many  commentators,  it  is  supposed 
that  Jesus  Christ  will  jreign  person- 
ally on  the  earth,  that  the  bodies 
of  martyrs  and  other  eminent 
Christians  will  be  raised  from  the 
dead,  and  in  this  renewed  state  con- 
stitute the  subjects  of  His  glorious 
kingdom 

MUUare^  a  Roman  mile,  consisting 
of  1000  paces  of  5  feet  each,  and 
therefore  »  5000  feet :  taking  the 
Roman  foot  at  11*6496  English 
inches,  the  Roman  mile  would  be 
1618  English  yards,  or  142  yards 
less  than  the  English  statute  mile. 

MiUt  for  the  grinding  of  grain  into 
flour  are  of  several  kinds :  wind- 
mills, with  sails  to  be  impelled  by 
the  action  of  the  wind,  over- shot 
and  under-shot;  and  the  horizontal, 
or  turbine  water-wheels.  Mill 
machinery  is  used  for  the  grinding 
of  tobacco  into  snuff,  impelled  by 
wind,  particularly  in  Holland,  where 
stupendous  structures  can  be  seen 
on  the  road  from  Rotterdam  to  the 
Hague.  MiUs  are  also  used,prope]led 
by  steam  or  water,  for  the  grinding 
of  bark,  preparing  of  flax,  sawing 
of  timber,  and  for  the  many  and 
varied  purposes  in  manufacture. 
In  the  'Papers  on  Engineering,' 
voL  vi.,  will  be  found  an  interesting 
paper  by  Mr.  Fairbaim  on  'Water- 
Wheels  with  Ventilated  Buckets.' 

MiUwrightt?  Pkmmg  Machine,  This 
machine  is  similar  in  principle  to 
the  ordinary  planing  machine  (see 
Planing  Machine)^  except  in  cases 
where  heavy  work  is  required  to  be 
planed,  when  a  machine  with^a 
moveable  tool  and  fixed  table  is 
used.  The  advantage  of  this  ar- 
rangement is,  that  very  large  and 
heavy  castings  are  planed,  which 
could  not  be  moved  to  and  fro,  as 

in  the  ordinary  machines,  without 

_ 


great  loss  of  power.  It  is  placed 
over  a  pit  made  for  the  purpose, 
with  steps  to  descend  into  it.  The 
two  side  frimies  are  bolted  to  the 
ground,  and  the  table  has  a  series 
of  apertures  for  bolts  to  fix  the 
work  upon  it,  and  can  be  raised  or 
lowered  to  any  required  height  by 
four  strong  screws,  one  at  each 
comer.  The  horizontal  and  ver- 
tical slides  are  placed  over  the  work 
in  the  usual  manner,  and  are  at- 
tached to  a  light  frame,  which, 
when  the  tool  is  adjusted  to  the 
work  by  the  vertical  slide,  is  moved 
to  and  fro,  carrying  with  it  the 
slides  and  tool,  and  at  the  end  of 
each  backward  stroke  a  lappet,  or 
other  contrivance,  sets  the  vertical 
slide  and  tool  a  little  further  across 
the  table,  until  the  entire  surface  is 
planed. 

Minaret,  in  Mohammedan  .architec- 
ture, a  spire  or  steeple 

Mineral  Black  is  a  native  and  impure 
oxide  of  carbon,  of  a  soft  texture, 
found  in  Devonshire 

Mineral  Green  is  the  commercial 
name  of  green  lakes,  prepared  from 
the  sulphate  of  copper 

Mineralogy  forms  one  of  the  three 
great  divisions  into  which  natural 
history  or  the  knowledge  of  natu- 
ral objects  has  been  classified ;  the 
other  two  being  botany,  devoted  to 
plants,  and  zoology,  to  animals. 
Mineralogy  is  also  distinguished 
frx>m  geology,  inasmuch  as  it  re- 
gards the  characters  of  minerals 
in  detail,  without  regard  to  their 
formation  and  general  distribution 
in  the  crust  of  the  earth,  which 
belong  to  geology.  If  the  compo- 
sition of  a  mineral  substance  is  to 
be  considered,  then  mineralogy 
forms  a  portion  of  chemistry ;  but 
in  its  more  limited  sense,  mine- 
ralogy is  the  art  of  distinguishing 
mineral  substances  from  each  other, 
and  the  science  of  accurately  de- 
scribing and  arranging  them,  by 
what  may  be  termed  a  natural  clas- 
sification. 

Minee.    Water-springs  in  mines  are 


MIN 


MITRE-WHEEL. 


MIX 


wrongly  considered  to  be  of  great 
injury.  It  is  true,  the  lifting  of 
water  by  machinery  from  the  deep 
mines  it  attended  with  expense, 
when  they  are  so  situated  that  no 
level,  drift,  or  water-course  can  be 
obtained  for  that  purpose ;  but,  on 
the  other  hand,  they  are  so  abso- 
lutely necessary  in  mining,  that  in 
the  very  first  process,  a  Judicious 
miner,  in  boring  down  to  his  mine, 
previous  to  his  sinking  to  or  wont- 
ing it,  even  in  this  simple  act, 
cannot  proceed  very  deep  without 
water  to  work  his  bore-Aid  in ;  and 
if  the  strata  of  the  earth  passed 
through  does  not  produce  it,  he 
must  pour  it  down  the  bore-hole, 
or  he  cannot  proceed.  When  all 
his  pits  or  shafts  are  sunk,  and  his 
mine  opened,  and  ventilation  is  re- 
quired to  expel  inflammable  air, 
fire,  or  black  damp  (as  it  is  termed), 
nothing  is  superior  to  water.  When 
this  can  be  obtained,  and  made  to 
run  with  facility  through  the  mine 
and  its  various  workings,  it  is  found 
superior  to  aur-fumaces  of  any  kind 
for  expelling  the  fulminating  va- 
pours so  destructive  to  the  health 
and  lives  of  the  workmen  employed. 

Mines  in  Scotland, — ^The  general  cus- 
tom of  Scotland  provides  for  yield- 
ing  to  the  landlord  a  royalty  pro- 
portioned upon  the  net  amount  of 
sales  at  the  colliery,  in  conjunction 
with  a  certain  or  sleeping  rent  pay- 
able half-yearly.  The  royalty  pro- 
portion is  sometimes  so  high  as 
one-quarter  the  amount  of  sales, 
but  generally  one-eighth ;  of  late 
years  many  collieries  have  been  let 
at  one-twelfth  and  at  one-four- 
teenth the  amount  of  sales. 

Mining.  There  is  an  essential  differ- 
MtCe  between  civil  and  military 
mining :  in  the  former,  the  works 
are  frequently  carried  on  at  consi- 
derable ,  depths  below  the  surface 
of  the  earth,  and  sometimes  in  solid 
rock;  whereas  military  mining  is 
what  may  be  termed  superficial, 
and  consequently  the  miner  works 
through  the  more  recent  formations 

288 


of  earths  and  sands,  which,  from 
their  little  tenacity,  he  has  to  sup- 
port as  he  advances.  For  the  bet- 
ter ventilation  of  military  mines,  a 
machine  has  been  invented  by  Ser- 
geant Lewis,  of  the  Royal  Sappers 
and  Miners ;  and  it  has  been  con- 
jectured that  Mr.  Haig's  patent 
pneumatic  engine,  invented  for  the 
purpose  <tf  purifying  the  holds  of 
vessels,  might  also  be  suocesaftilly 
employed  in  mining  operations.* 

MinsteTf  a  cathednd,  anciently  a 
large  church.  (See  tFe9tmmgt€r 
Abbey.) 

Minutef  a  proportionate  measure  in 
architecture,  by  which  the  parts  of 
the  orders  are  regulated ;  the  six- 
tieth part  of  the  lower  diameter  of 
the  shaft  of  a  column,  vnritten  thus, 
Wt  i'6-  ten  minutes ;  in  geography 
and  astronomy,  the  sixtieth  part  of 
a  degree 

Misereret  projecting  brackets  in  the 
under  side  of  the  seats  of  stalls  in 
churches;  they  are  always  more 
or  less  ornamented  with  carvings  of 
leaves  and  grotesque  subjects 

3ft/r«,  an  episcopal  crown.  In  carpen- 
try, the  Une  formed  by  the  meeting 
of  mouldings  or  other  surfEices 
which  intersect  each  other.  If 
two  pieces  of  wood  be  formed  to 
equal  angles,  or  if  the  two  sides  of 
each  piece  form  equal  inclinations, 
and  thus  be  joined  together  at  their 
common  vertex,  so  as  to  make  an 
angle  double  to  that  of  either 
piece,  they  are  said  to  be  mitred 
together,  and  the  joint  is  called 
*the  mitre.* 

Mitre-wheel,  a  wheel  having  teeth 
formed  so  as  to  work  at  an  angle 
of  45°  to  the  centre  line  of  the 
shaft  on  which  it  is  fixed,  to  move 
with  another  wheel  of  equal  size, 
fixed  on  a  shaft  at  right  angles  to 
the  former  one 

MiJped  Citrine.  There  are  two  prin- 
ciples of  combination,  of  which  the 
artist  may  avail  himself  in  pro- 
ducing these  colours;  the  one  being 
that  of  combining  two  original  se- 
condaries, green  and  orange  in  pro- 


MIX 


MONASTERY. 


MON 


dncing  a  citrine;    the  other,  the 
uniting  the  three  primaries  in  snch 
a  manner  that  yellow  may  predomi- 
nate in  the  case  of  citrinei  and  blue 
and  red  be  subordinate  in  the  com- 
pound. 
Mixed   Grayt   are  formed   by  the 
compounding  of  black  and  white, 
which  yields  neutral  grays,  and  of 
black  and  blue,  black  and  purple, 
black  and  oliye,  &c 
Mixed  Cfreene,  compounds  of  blue 
and  yellow  pigments,  which  may 
be  formed  by  compounding  them  in 
the  several  ways  of  working,  or  by 
blending  them  in  the  proportions 
of  the  Tarious  hues  required 
Mixed  OSve  is  compounded  by  unit- 
ing green  and  purple  colours,  or  by 
adding  to  blue  a  smaller  proportion 
of  yellow  and  red,  or  by  breaking 
much  blue  with  little  orange 
Mixed  Orange,  Orange  being  a  colour 
compounded  of  red  and  yellow,  the 
place  of  original  orange  pigments 
may  be  supplied  by  a  mixture  of  the 
two  latter  colours,  by  glazing  one 
over  the  other;  by  stippling,  or 
other  modes  of  bresJcing  and  inter- 
mixing  them  in  working,  according 
to  the  nature  of  the  work  and  the 
effect  required. 
Mixed  Purple,    Purple  being  a  se- 
condary colour,  composed  of  blue 
and  red,  it  follows  of  course  that 
any  blue  and  red  pigments  which 
are  chemically  at  variance  may  be 
used  in  producing  a  mixed  purple 
of  any  required  hue,   either  by 
compounding  or  by  grinding  them 
together  ready  for  use,  or  by  com- 
bining them  in  the  various  modes 
of  operation  in  painting. 
Mixed  Russet,    Orange,  vermillion, 
and  madder  purple  afford  a  com- 
pound russet  pigment  of  a  good 
and  durable  colour. 
Mizen-mast,  in  ship-rigging,  the  mast 

next  the  stem 
Mock  leadt  wild  lead,  black  lead,  or 
black  jaekf  a  ponderous  black  mi- 
neral, which  does  not  readily  in- 
corporate in  the  fire ;  a  zinc  ore 
Model,  a  pattern  used  for  moulding ; 

289 


a  machine  or  building  executed  in 
miniature 
Modillion,  a  projecting  bracket  imder 
the  corona  of  the  Corinthian  and 
Composite  orders,  and  sometimes 
of  the  Roman  Ionic 
Module,  a  measure  of  proportion  by 
which  the  parts  of  an  order  or  of  a 
building  are  regulated  in  classical 
architecture;  considered  generally 
as  the  diameter  or  semi-diameter 
of  the  lower  end  of  the  shaft  of  the 
column ;  in  other  words,  semi-dia- 
meter of  the  column,  or  30  mi- 
nutes 

Molecule,  synonymous  with  atom,  in 
physics,  a  very  small  mass  or  por- 
tion of  any  body 
Molybdenum,  a  brittle  and  white  glo- 

bulous  metal 
Momentum,  in  dynamics,  is  the  force 
of  a  body  in  motion.    'When  the 
motion  of  a  body  is  considered  with 
respect  to  the  mass,  or  quantity  of 
matter  moved,  as  well  as  its  ve- 
locity, it  is  called  its  momentum, 
or  quantity  of  motion.    The  mo- 
mentum of  a  body  is  therefore  in 
the  compound  ratio  of  its  quantity 
of  matter  and  velocity. 
Monastery,  an  establishment  for  the 
accommodation  of  a  religious  fra- 
ternity, who  made  it  the  receptacle 
of  benevolence  and  charity  for  the 
poor  and  the  way-worn.     A  con- 
siderable portion  of  the  land  was 
formerly  occapied  by  the  monas- 
teries and  other  religious  houses 
which  existed  in  Britain,  and  the 
endowments    of  these   establish- 
ments   subsequently  became   the 
foundation  of  the  great  wealth  of 
some  of  the  early  aristocracy  in 
England. 

Of  the  ample  means  enjoyed  by 
the  inmates  of  these  cloistered  sanc- 
tuaries, some  idea  may  be  formed 
from  the  follovring  historical  state- 
ment, translated  from  the  preface 
to  the '  Ely  Cartulary,'  preserved  in 
the  Public  Library  at  Cambridge. 
After  the  defeat  and  death  of 
Harold,  many  of  the  leading  men 
of  the  realm,  who  had  strenuously 


MON 


MONASTERIES. 


MON 


opposed  the  Bast&rd»  fled  for  re- 
fuge to  Ely  Monastery,  together 
with  their  Mends,  "laden  with 
their  richest  treasures,"  and  with- 
stood, for  seven  years,  the  im- 
petuous threatenings  of  the  Nor- 
mans, until  they  were  unexpectedly 
surprised.  **  Then  a  council  being 
held,  it  seemed  advisable  to  implore 
the  royal  mercy ;  upon  which  some 
were  despatched  to  the  king's 
court,  at  that  time  at  Warwidc, 
carrying  rich  treasures  to  the  king, 
the  gift  of  atonement  and  compen- 
sation of  their  misconduct;  with 
which  the  king  was  satisfied,  but 
on  these  terms  and  conditions, — 
that,  during  his  pleasure,  forty 
royal  officers  should  be  lodged  at 
the  expense  of  the  monastery.  *  * 
The  knights  are  sent  for,  they 
arrive,  and  are  present  with  their 
household,  every  one  of  whom  has 
under  him  a  monk  of  the  first  order, 
as  an  officer  under  his  earl,  or  a 
guest  wider  his  host.  But  the 
king  ordered  that  the  cellarer 
should  dispense  provisions  to  the 
officers  and  monks  promiscuously 
in  the  public  hall  of  the  convent.  In 
short,  the  officers  with  their  earls, 
the  guests  with  their  hosts,  the 
knights  with  their  monks,  the 
monks  with  their  knights,  were 
most  grateful  to  each  other;  for 
each  and  all  of  them  mutually 


afforded  each  other  the  offices  of 
humanity." — ^Afterfive  years  passed 
in  this  way,  the  knights  were  re- 
called by  the  Conqueror,  to  assist 
in  punishing  the  unnatural  wicked- 
ness of  his  son  Robert ;  and  **  they 
departed  withgrief;  and  our  monks, 
wonderful  to  relate,  lamented  the 
departure  of  these  most  illustrious 
companions,  heroic  knights,  and 
most  pleasing  guests,  not  only  in 
tears,  but  in  dismal  bowlings  and 
exclamations,  and  struck  their 
breasts  in  despair,  after  the  man- 
ner of  a  bride  whose  husband  is 
unseasonably  hurried  from  *  her 
sweet  embraces  to  arms." — ^All  the 
monks  accompanied  the  knights  as 
far  as  Hadenham,  vnth  hymns, 
crosses,  thuribals,  processions,  and 
every  solemnity,  and,  when  re- 
turned, took  care  to  paint  the  arms 
of  each  knight  on  the  walls  of  the 
refectory,  to  the  perpetual  remem- 
brance of  the  uncommon  humanity 
of  their  military  guests." — In  the 
cartulary  the  names  of  the  knights, 
forty  in  number,  with  their  com- 
panions, are  given ;  and  their  arms 
are  emblazoned  on  the  margin. 

In  addition  to  the  monasteries 
and  nunneries  enumerated  in  the 
following  alphabetical  list,  no  less 
than  131,  which  are  unnoticed  in 
the  Books,  are  said  to  have  been 
scattered  over  England  and  Wales. 


NAMB. 

ORDER. 

DMFE. 

COUNTY. 

Amesbury    .... 

Benedictine 

980 

Wiltshire 

Ankerwyke  . 

Benedict.NunR 

1257 

Buckinghamshire 

Arden     .    .    . 

Do. 

1150 

Yorkshire 

Arklow   .    .    . 

Benedictine 

Wicklow 

Armethwaite    . 

Nunnery 

Wm.  Rufus 

Cumberland 

Arthington  . 

Do. 

1254 

Yorkshire 

Ashbridge    . 

Augustine 

1283 

Buckinghamshire 

Austin  Canons 

Do. 

1147 

Huntingdon 

Austin  Cell      . 

Do. 

1126 

Norfolk 

Austin  Cell 

Do. 

1256 

Norfolk 

of  Casham  on  Tweed 

Do. 

1296 

Northumberland 

„     of  Taversham 

Do. 

1162 

Oxfordshire 

„     of  Halywell  . 

Do. 

1325 

Warwickshire 

Austin    Nunnery  of  1 
Legh   ....   J 

Do. 

Henry  II. 

Devonshire 

Aylesford     .    . 

« 

.1 

Carmelite 

1240 

Kent 

290 


MON 


MONASTERIES. 


MON 


NAME. 

Badlesmere . 
Barking  .    • 
Basseiech     . 
Bearwe  .    . 
Beaulieu .    . 
Beauvale .    . 
Benedictine  Cell 
Birkenhead . 
Blackborough 
Blakeney     . 
Bleatarn .    . 
Blythebury  . 
Bretford .    . 
Brewood 
Brewood 
Brodholm    . 
firomfield    . 
Bromhale    . 
Brunham     . 
Bungay  .    . 
Calewich  Cell 
Calke .     .    . 
Canwell  .    . 
Canyngton  . 
Carow     .    . 
Castle  Hedingham 
Catesby  .    . 
Cell  of  Lees 
Charter-house 
Chateris  .    . 
Cheshunt     . 
Chester  .    . 
Clerkenwell 
Clonard  .    . 
Clynnock  Vaux 
Codenham   . 
Cokehill .     . 
Cokwelle     . 
Cohi  .    .    . 
Comworthy 
Crabhouse   . 
Dartford .    . 
Davington   . 
Derby     .    . 
Dodford .    . 
Dunster  .    . 
Durham  College 
East  Dereham 
EUerton  .    . 
Elstow    .    . 
Fairwell  .    - 
Fame  Island 
Felixtow .    . 


OBDEa. 

Augustine 
Nunnery 

Do. 

Benedictine 

Carthusian 

Benedictine 
Do. 

Carmelite 
Cistercian 


Nunnery 

Cist.  Nunnery 

Nunnery 

Do. 

Do. 

Nun  Priory 

Nunnery 

Augustine 

Do. 


Nunnery 
Do. 
Do. 
Do. 

Carthusian 

Nunnery 

Do. 

Do. 

Do. 

August.  Nun. 

Cistercian 

Nunnery 

Cist.  Nunnery 

Do. 

Nunnery 
August.  Nun. 
Nunnery 
Benedict.  Nun. 
Nunnery 
Cell  Premonst. 
Benedictine 
Ed»- of  Monks 

Cist.  Nunnery 

Nunnery 

Benedictine 

Do. 

Do. 


DATE. 

Edward  II. 
630 
1101 
1200 
1113 
1347 
1349 
1150 
1200 
1321 

Henry  I. 

1295 
Richard  I. 
Edward  II. 

1115 

1268 

1262 

1160 

1148 

1161 

1142 

1140 

1146 

1190 
Richard  I. 

1348 

980 
1183 
1264 
1100 
1195 

616 
Henrv  II, 
1260 
1185 
1100 
1461 
1181 
1355 
1153 
1160 
1184 
Wm.  Conq. 
1285 

650 
Edward  I. 
1078 
1140 

651 
Wm.  Rufus 


COUNTT. 

Kent 

Essex 

Monmouthshire 

Somersetshire 

Hertfordshire 

Nottinghamshire 

Cambridge 

Cheshire 

Norfolk 

Norfolk 

Westmoreland 

Staffordshire 

Warwickshire 

Staffordshire 

Shropshire 

Nottinghamshire 

Shropshire 

Berkshire 

Yorkshire 

Suffolk 

Staffordshire 

Derbyshire 

Staffordshire 

Somersetshire 

Norfolk 

Essex 

Northamptonshire 

Staffordshire 

London 

Cambridgeshire 

Hertfordshire 

Cheshire 

Middlesex 

Meath 

Carnarvonshire 

Yorkshire 

Worcestershire 

Lincolnshire 

Essex 

Devonshire 

Norfolk 

Kent 

Kent 

Derbyshire 

Worcestershire 

Somersetshire 

Oxford 

Norfolk 

Yorkshire 

Bedfordshire 

Staffordshire 

Northumberland 

Suffolk 


291 


MON 


MONASTERIES. 


MON 


} 


NAME. 

Flamstead 
Floxton  . 
Folkestone 
Fosse .    . 
Gloucester  CoUegi 

or  Hall 
Godeland 
Godestow 
Goring    . 
Grany 
Greisley  . 
Grimesby 
HaUwell. 
Handale . 
Henwood 
Heyninges 
Hinchingbrook 
Hode.    . 
Holystan 
Horewelle 
Home     . 
Ikelington 
Ilchester  Hospital 
Inch  Colme 
Ivingho  . 
Jarrow    . 
Kaylend  . 
Kells  and  Inistioge 
Kilbum  . 
Kirklees  . 
Lacock    . 
Lakebnm 
Lambly  upon  the  Tyne 
Lammana    . 
Langley  .    . 
Lestingeham 
Letteringham 
Liming    .    . 
Lindisfame  . 
Littlechurch 
Little  Mards 
Little  Marlow 
Littlemore   . 
Llanlorgan  . 
Lymbroke    . 
MalUng  .    . 


Malpas- 

Marham  .  . 

Marrick  .  . 

Marton    .  . 

Mergate  .  . 
Middleburgh 

Middleton  . 


OHDKB. 

Benedict.  Nun. 
Nunnery 

Cist.  Nunnery 
Benedictine 

Nunnery 

Do. 

Benedict.  Nun. 

Augustine 

Benedictine 

Nunnery 

Do. 

Cist.  Nunnery 

Nunnery 

CeU 

Nunnery 

Cistercian 

Nunnery 

Do. 

Augustine 

Nunnery 

Benedictine 

Premonstrant 

Augustine 

Nunnery 

Cist.  Nunnery 

Nunnery 

Cist.  Nunnery 

Nunnery 

Benedictine 

Nunnery 

Augustine 


Nunnery 
Benedict.  Nun. 
Nunnery 
Benedict.  Nun. 
Cist.  Nunnery 

Nunnery 

Cluniac 

Cistercian  Nun 

Nunnery 

Augustine 

Benedictine 

Benedictine 

Do. 


DATE. 

1220 
1258 
630 
Henry  III. 

1260 

King  John 

1138 
Henry  II. 

1200 
Henry  I. 

1185 

1127 

1133 

1228 

1180 
Wm.  Conq. 

1138 

1255 
•  1291 

1226 

1140 

1217 

1133 

1160 
684 

1183 
1191 
1291 
1232 
1150 
1292 
1200 
King  Canute 
648 

633 
1082 
1151 
1163 
1230 
1177 
1239 
1036 

945 
Henry  I. 
1249 
1171 
temp.  Steph. 
1145 
1120 

933 


COUNTY. 

Hertfordshire 
Suffolk 
Kent 
Lincolnshire 

Oxford 

Yorkshire 

Oxfordshire 

Oxfordshire 

Kildare 

Derbyshire 

Lincolnshire 

Middlesex 

Yorkshire 

Warwickshire 

Lincolnshire 

Huntingdonshire 

Yorkshire 

Northumberland 

Warwickshire 

Suffolk 

Cambridgeshire 

Somersetshire 

Fifeshire 

Buckinghamshire 

Durham 

Northamptonshire 

Kilkenny 

Middlesex 

Yorkshire 

Wiltshire 

Lincolnshire 

Northumberland 

Cornwall 

Leicestershire 

Yorkshire 

Suffolk 

Kent 

Northumberland 

Kent 

Yorkshire 

Buckinghamshire 

Oxfordshire 

Montgomeryshire 

Herefordshire 

Kent 

Monmouthshire 

Norfolk 

Yorkshire 

Yorkshire 

Bedfordshire 

Yorkshire 

Dorsetshire 


292 


MON 


MONASTERIBS. 


MON 


} 


NAME. 

Molesby 

Monkton  .  .  .  . 
Neddrum  .  .  .  . 
Newcastle  .  .  .  . 
Nim-Appleton  .  .  . 
Nun-Cotun  •  .  .  . 
Nun-Kelynge    .     .    . 

Oxney 

Peykirk 

Pinley 

Pinwortham  .  •  . 
Polslo      .    .    •    .    . 

Reculver 

Redburne  .  •  .  • 
Redlingfield .  .  .  . 
Reinton,  St.  Michael . 

Rosedale 

Rothwell 

Rowney  .    •    .    •    • 

Ramsey 

Rusper 

Scarthe  .... 
Scilly,  in  the  Isle  of 

Tnescaw 
Sdsey     .    . 
Seton .    .    . 
Sewardesley 
Shepey    .    • 
Suiningthwaite 
Snelleshall  . 
Sopwell  .    . 
Stanfeld  .    . 
Stanford .    . 
St.  Anne .    . 
St.  Bartholomew 
St.  Bernard's  College. 
St.  Clement 
St.  Dogmael 
St.  Edmund's  Bury 
St.  German's    . 
St.  Helen     .    . 
St.  Ive  (Cell  of) 
St.  John  Baptist 
St.  Martin's.     . 
St.  Mary  de  Pr^ 
St.  Mary  Magdalen 
St.  MUdred's    . 
St.  Nicholas      . 
St.  Rategund    . 
St.  Sepulchre's 
St.  Syriae    .    . 
Stodely   .    .    . 
Stratford  at  Bow 


ORDER. 

Nunnery 

Benedictine 
Black  Friars 
Cistercian 
Do. 
Nunnery 


Benedictine 

Do. 

Nunnery 

Nunnery 

Do.* 

Do. 

Do. 

August.  Nun. 

Nunnery 

Benedictine 

Nunnery 

Augustine 


Benedict.  Nun. 

Cisterc.  Nun. 

Nunnery 

Cistercian 

Black  Monks 

Nunnery 

Do. 

Benedict.  Nun. 

Carthusian 

Nunnery 

Cistercian 

Nunnery 


Benedictine 

Nunoery 

Benedictine 

Do. 

Do. 

Do. 

Nunnery 

Benedictine 

Benedict.  Nun. 

Nunnery 

Cluniac 

Nunnery 

Benedictine 


DATE. 

1167 
1268 
1177 
1260 
K.  Stephen 

1152 

714 
1195 
Wm.  Conq. 
1169 

669 
1178 
1120 
1274 
1310 
1305 
1164 

967 

1291 

Henry  I. 

1346 

711 

1227 

Henry  II. 

675 
1160 
1219 
1140 
1278 
1156 
1381 
1086 
1437 
1130 
Wm.  Conq. 

633 

614 
1212 
1001 
Edward  I. 
1100 
1190 
1170 

670 

1103 

1130 

1100 

Richard  I. 

1184 
Wm.  Conq. 


COUHTT. 

Yorkshire 

Yorkshire 

Devon 

Northumberland 

Yorkshire 

Lincolnshire 

Yorkshire 

Northamptonshire 

Northamptonshire 

Warwickshire 

Lancashire 

Devonshire 

Kent 

Hertfordshire 

Suffolk 

Wiltshire 

Yorkshire 

Northamptonshire 

Hertfordshire 

Hampshire 

Sussex 

Yorkshire 

Cornwall 

Sussex 

Cumberland 

Northamptonshire 

Kent 

Yorkshire 

Buckinghamshire 

Hertfordshire 

Lincolnshire 

Northamptonshire 

Warmckshire 

Northumberland 

Oxford 

Yorkshire 

Pembrokeshiie 

Suffolk 

Cornwall 

London 

Huntingdonshire 

Cork 

Yorkshire 

Hertfordshire 

Bristol 

Kent 

Exeter 

Cambridgeshire 

Canterbury 

Cornwall 

Oxfordshire 

Middlesex 


293 


MON 


MOORISH  ARCHITECTURE. 


MOO 


NAME. 

ORDER. 

DATE. 

corafTY. 

Stykoswold  .... 

Cisterc.  Nun. 

K.  Stephen 

Lincolnshire 

Swaffham    .    , 

Nunnery 

1255 

Cambridgeshire 

Syon  •    .    . 

Do. 

1414 

Middlesex 

Tarent     .    . 

Cisterc.  Nun. 

Richard  I. 

Dorsetshire 

Thicked  .    . 

Nunnery 

1214 

Yorkshire 

Trentham     . 

Augustine 

Henry  I. 

Staffordshire 

WallingweU.    , 

Aug:ust.  Nun. 

K.  Henry 

Northamptonshire 

WherweU     .    . 

Nunnery 

986 

Hampshire 

Whiston .    .    . 

Cisterc.  Nun. 

1255 

Worcestershire 

Wilberfosse .    . 

Nunnery 

1153 

Yorkshire 

WUton    .    .    . 

Benedictine 

773 

Wiltshire 

Winchester  .    . 

Nunnery 

900 

Hampshire 

Winteneye   .    , 

.    .  :  Cisterc.  Nun. 

1200 

Hampshire 

WroxhaU     .    . 

.    Benedictine 

Wm.  Conq. 

Warwickshire 

Wyckham    .    , 

.    .  1  Cisterc.  Nun. 

1153 

Yorkshire 

Wykes     .    .    . 

.Do. 

Henry  II. 

Essex 

Wyrthorp     .    , 

.    Nunnery 

1357 

Northamptonshire 

Yarmouth    .    . 

# 

Benedictine 

1101 

Norfolk 

Monkey-wrench,  a  spanner  with  a 
moveable  jaw,  which  can beadjusted 
by  a  screw  or  wedge  to  the  size  of 
the  nut  which  it  is  required  to 
turn 

Mwiogram,  a  cipher  composed  of  two 
or  more  letters  interwoven  as  an 
abbreviation  of  a  name :  monograms 
were  common  as  distinctive  marks 
on  ancient  coins,  and  were  also 
used  as  seals 

MonoHthiCf  consisting  of  a  single 
stone :  statues,  columns,  and  pillars 
were  formed  by  the  ancients  out  of 
large  blocks  of  stone  or  marble 

Monopteral,  a  temple  which  has  no 
cella,  but  consists  of  columns  dis- 
posed in  the  form  of  a  circle,  co- 
vered with  a  conical  roof 

Monota,  a  vase  vnth  one  handle 

Monotrifflyph,  the  interval  observed 
between  the  columns  of  a  Doric 
portico,  where  a  space  is  left  suf- 
ficient for  the  insertion  of  one  tri- 
glyph  only  between  those  immedi- 
ately over  two  contiguous  columns 

Morutranee,  sometimes  called  Eemon^ 
itrance,  the  vessel  in  which  the 
consecrated  wafer  or  host  is  placed 
while  the  congregation  are  blessed 
with  it,  in  the  Roman  Catholic 
Church.  In  the  *  Divers  Works  of 
Early  Masters,'  2  vols,  folio,  will  be 
found  two  of  the  rarest  and  most 

294 


elaborate  examples  of  tabemadea 
or  canopies,  in  a  compartment  of 
either  of  which  the  casket  or  yessel 
containing  the  sacred  vessel  is  de- 
posited. 

Montofif  a  heap  of  ore ;  a  batch  under 
process  of  amalgamation,  varying 
in  different  mining  districts 

Monument,  a  mausoleum  or  tomb. 
Sepulchral  monuments  of  the  mid- 
dle ages  still  exist  to  a  considerable 
extent,  both  here  and  on  the  Con- 
tinent. Monuments  and  tombs  of 
modem  date  are  designed  from 
Classical  and  Gothic  architectmre, 
and  in  many  instances  are  beautiful 
models  of  modem  art. 

Moor,  in  Cornish,  a  root,  or  quantity 
of  ore  in  a  particular  part  of  a  lode, 
as  a  '  moor  of  ore,'  a  '  moor  of  tin' 

Moorish,  Mohammedan,  or  Saracenic 
Architeetvre,  is  a  combination  of 
Egyptian,  Grecian^  and  Roman  de- 
tails; first  established  by  the  Arabs 
about  the  tenth  century,  and  for 
oriental  scenery  of  a  pleasing  cha- 
racter: its  complicated  ornament 
and  lattice-work  are  rich  and  pecu- 
liar. Many  existing  examples  are 
interesting ;  but  the  style  is  wholly 
unfit  for  European  usages  and  re- 
quirements. 

Moot-hall,  or  MooUhouse,  in  Saxon 
times,  a  building  appropriated  to 


MOR 


MORTAR. 


MOR 


assemblies  on  public  affairs ;  a  guild- 
hatt  or  town-halif  hdtel  de  villet  &c. 

Mora  wood.  This  tree  is  100  feet 
high,  and  abundant;  it  is  close- 
grained,  like  teak,  and  superior  to 
I      oak ;  esteemed  for  ship-building. 

Moresque,  a  kind  of  painting,  carving, 
&c.,  in  the  arabesque  and  grotesque 
styles  of  ornament 

Mortar.  The  materials  which  are 
added  to  lime,  in  the  formation  of 
mortars  or  calcareous  cements,  are, 
1st,  The  different  kinds  of  sand, 
properly  so  called;  2nd,  arenes; 
3rd,  psammites;  4th,  clays;  5th, 
yolcanic  or  pseudo-volcanic  pro- 
ducts ;  and  6th,  artificial  products 
arising  from  the  calcination  of  the 
clays,  the  arenes,  and  the  psam- 
mites ;  and  the  rubbish  and  slag  of 
manufactories,  foiges,  &c. 

INGREDIENTS  OF  MORTAR. 

Sand. — The  granitic,  schistose, 
and  calcareous  rocks,  free-stones, 
&c.,  reduced  to  the  state  of  hard 
and  palpable  grains,  either  by  the 
agitation  of  veater,  or  by  spontane- 
ous disaggregation,  give  birth  to 
the  various  kinds  of  sand.  We  dis- 
tinguish them  from  powders  by 
their  falling  at  once  to  the  bottom, 
when  thrown  into  limpid  water, 
and  that  without  altering  its  trans- 
parency in  a  sensible  degree. 

The  disaggregation  of  rocks  is 
often  accompanied  by  a  decomposi- 
tion which  produces  a  powder: 
this  powder  renders  the  sand  *rich,' 
or,  in  other  terms,  susceptible  of  a 
certain  cohesion,  when  tempered 
with  water.  Washed  by  rains  and 
currents  of  water,  it  is  soon  freed 
from  the  pulverulent  particles,  and 
is  deposited  pure  in  the  beds  of 
rivers.  This  purity  is  often  changed 
near  the  mouths  of  streams,  and  in 
the  small  rivulets  whose  tributaries 
flow  over  a  bed  of  clay  or  mould : 
the  sand  mixes  with  vegetable  d^ 
bris  and  animal  matters,  and  be- 
comes '  loamy.'  The  particles  com- 
posing sand  faithfully  represent 
those  of  the  rocks  whence  they  are 

295  ' 


derived.  The  granitic  regions  fur- 
nish quartz,  felspar,  and  mica;  and 
the  volcanic  regions,  lavas  of  all 
kinds.  The  tabular-shaped  sands, 
whose  particles  are  tender,  are  fur- 
nished by  the  schistose  mountains. 
It  is  difficult  for  them  to  be  trans- 
ported far  without  being  reduced 
to  powder. 

The  calcareous  sands  are  the 
least  common,  probably  arising 
from  the  fact  that  rivers  generally 
take  their  rise  from  primitive  sum- 
mits, or  such  as  are  composed  of 
primitive  elements.  The  calcareous 
rocks,  besides,  are  not  susceptible 
of  that  kind  of  disaggregation  which 
can  be  called  granitic ;  for  if  they 
be  of  a  soft  kind,  they  produce 
powder ;  if  hard,  scaly  splinters. 

The  partial  and  secondary  revo- 
lutions of  the  globe  have  occasioned 
immense  deposits  of  sand  in  situa- 
tions where  now  neither  brooks 
nor  rivers  flow :  these  are  the  fos- 
sil sands;  and  they  should  be  care- 
fully distinguished  from  the  virgin 
sands,  which  are  stiU  in  their  origi- 
nal  site,  and  have  not  been  operated 
on  by  the  waters. 

The  fossil  sands  generally  exhibit 
a  more  angular  grain  than  the  sea 
or  river  sands;  but  in  other  re- 
spects they  are  the  same  elements, 
sometimes  pure,  sometimes  coloured 
by  ochres,  &c. 

Among  the  fossil  sands  is  one 
very  remarkable,  the  .arene.  Its 
properties  entitle  it  to  attention. 

Arbnb's  is  a  sand,  generally 
quartzose,  with  vary  irregular,  un- 
equal grains,  and  mingled  with 
yeUow,  red,  brown,  and  sometimes 
white  clay,  in  proportions  varying 
fit>m  one  to  three-foorths  of  the 
whole  volume. 

The  arene  almost  always  occu- 
pies the  summits  of  the  rounded 
and  moderately-elevated  hills:  it 
sometimes  constitutes  entire  hil- 
locks; frequently  it  interposes  it- 
self in  large  veins  and  seams  in  the 
clefts  of  calcareous  rocks :  ,it  be- 
longs essentially  to  alluvial  toils. 


MOR 


MORTAR. 


MOR 


PsAMMiTEs  is  a  term  applied  to 
an  assemblage  of  the  grains  of 
quartz,  schist,  felspar,  and  particles 
of  mica,  agglutinated  by  a  yariable 
cement.  The  yarieties  of  these  are 
very  numerous :  those  which  in  ap- 
pearance strongly  resemble  the 
free-stones  and  silidous  breccias 
belong  to  the  dass  of  rocks  whose 
disaggregation  furnishes  sand,  pro- 
perly so  called.  But  the  psam- 
mites,  which  are  slaty,  of  a  yellow, 
red,  or  brown  colour,  fine-grained, 
unctuous  to  the  touch,  producing  a 
clayey  paste  with  water,  form  a 
distinct  species,  and  one  which 
merits  attention. 

These  last  belong  to  the  primi- 
five  schistose  formations :  they  do 
not  and  cannot  exist  except  m  situ: 
they  are  found  in  beds  or  veins, 
forming  part  of  the  schist  of  which 
they  are  merely  a  decomposition. 

Clats  are  earthy  substances  va- 
riously coloured,  fine,  soft  to  the 
touch,  which  diffuse  in  water  with 
facOity,  forming  with  it  a  paste, 
which,  when  kneaded  to  a  certain 
consistency,  possesses  unctuosity 
and  tenacity,  and  may  be  drawn 
out  and  kneaded  in  every  direction 
without  separating.  The  clayey 
paste,  when  dried,  retains  its  soli- 
dity, hardens  in  the  fire,  &c. 

Clays  are  essentially  composed 
of  nlica  and  alumina:  these  two 
substances  are  adulterated  by  the 
presence  of  the  oxide  of  iron,  the 
carbonates  of  lime  and  magnesia, 
snlphuret  of  iron,  and  of  vegetable 
combustible  matter  partly  decom- 
posed. 

The  clays  are  separated  into  four 
classes :  viz.  the  refractory,  which 
resist,  without  melting,  the  heat  of 
the  porcelain  furnaces  (140**  Wedg- 
wood); the  fusible  days;  the  ef- 
fervescing or  clayey  marls;  and, 
lastly,  the  ochrey  clays,  coloured 
red  or  pure  yellow  by  oxide  of  iron. 

The  position  of  clays  is  very  va- 
ried :  they  are  found  as  veins  in  pri- 
mitiye  formations ;  in  hillocks,  on 
the  confines  of  the  primitive  chains; 

~296 


in  horizontal  beds,  or  layers,  in  the 
secondary  formations;  in  threads, 
thin  veins,  or  infiltrations,  in  chinks 
and  hollows  of  calcareous  masses ; 
lastly,  in  volcanic  regions,  where 
their  formation  is  attributed  to  the 
decomposition  of  the  compact  lavas, 
and  perhaps  also,  with  some  proba- 
bility, to  miry  eruptions. 
Mortar,  Considered  as  a  plastic 
material,  mortar  fit  for  moulding 
may  be  made  to  take  every  pos- 
sible form  in  moulds  or  shapes. 
To  give  it  the  appearance  of  stone, 
it  should  be  made  with  fine  colour- 
less sand,  or  rather  with  fine  calca- 
reous powders  derived  from  hard 
stones. 

Mortar  contained  in  a  mould  may 
be  beaten  or  rammed  in  the  manner 
of  pis^, — "a  mode  of  building  for- 
merly in  use,  whereby  walls  were 
formed  by  ramming  and  beating 
down  earth,  day,  &c.,  between  up- 
right planks,*' — and  acquires  by 
that  means  great  compactness ;  but 
an  increase  of  resistance  does  not 
always  result  from  this. 

In  order  that  any  material  be 
beaten  with  effect,  it  is  necessary 
that  it  should  possess  a  certain  de- 
gree of  consistency,  which  is  a  mean 
between  complete  pulverulence  and 
that  state  of  ductility  which  con- 
stitutes a  firm  paste.  No  compres- 
sion is  possible  when  the  material 
escapes  from  under  the  rammer; 
and  this  is  still  practised  by  the 
builders  in  pis^,  who  never  employ 
any  but  earth  slightly  moistened. 
Mortar  may  always  be  prepared  in 
this  way,  leaving  it,  after  it  has  been 
worked  in  the  ordinary  manner,  to 
undergo  desiccation  to  a  proper 
extent. 

The  successive  approximation  of 
the  particles  of  the  compressed 
material  to  one  another  neces- 
sarily determines  a  foliated  struc- 
ture, which,  though  it  may  not 
be  perceived,  is  nevertheless  real. 
Analogy  will  lead  to  the  condusion, 
that,  in  every  possible  case,  a  body 
thus  formed  ought  to  oppose  a 


MOR 


MORTISE  AND  TENON. 


MOR 


greater  resistance  to  a  tractile  force 
in  proportion  as  its  direction  forms 
a  smaller  angle  'with  the  plane  of 
the  laminae;  however,  experience 
shows  that  this  in  general  does  not 
take  place.  The  following  has  been 
determined  in  this  respect: 

1st,  Beating  has  the  effect  of 
augmenting  the  absolute  resistance 
of  mortars  of  rich  limes  and  pure 
sand  in  eyery  case,  but  in  an  un- 
equal manner.  The  greatest  re* 
sistance  assumes  a  direction  per- 
pendicular to  the  planes  of  the 
laminae  when  the  mortars  are  buried 
in  a  damp  soil  immediately  after 
their  fabrication.  It  remains  par- 
allel to  these  same  planes  when 
the  mortars  have  been  exposed  to 
the  atmospheric  influence. 

2nd,  The  effect  of  beating  is 
not  constantly  useful  to  mortars  of 
hydraulic  or  eminently  hydraulic 
limes,  and  calcareous  or  quartzose 
sands  or  powders,  except  in  the 
case  when  these  mortars  are  used 
under  a  damp  soil.  The  greatest 
resistance  is  then  in  a  direction 
perpendicular  to  the  planes  of  these 
lanunae,  as  with  the  mortars  of  rich 
limes ;  but  in  the  air,  the  superiority 
of  the  mortars  which  have  been 
beaten  over  those  which  have  not 
is  only  exhibited  in  one  direction, 
and  that  is  parallel  to  the  plane  of 
the  laminae. 

3rd,  Beating  becomes  injurious 
in  every  case  when  the  hydrates  of 
the  hy^ulic  or  eminently  hydraulic 
limes  are  employed  without  admix- 
ture, and  subjected  to  the  influence 
of  a  damp  soil ;  and  is  favourable 
to  it  only  in  the  direction  parallel 
to  the  laminae  when  the  stuff  dries 
in  the  air. 

Considered  as  a  plastic  substance, 
the  numerous  casts  which  have  been 
moulded,  both  in  bas-relief  and  alto- 
reUevo,  prove  that  mortar  receives 
and  retains  impressions  weU :  their 
hardness  is  continually  on  the  in- 
crease, and  a  kind  of  varnish,  with 
which  time  covers  them,  gives  them 
a  strong  resemblance  to  stone. 

297 


One  problem  remains  to  be 
solved,  viz.  to  discover  a  means  of 
hastening  the  set  of  mortar  vrith- 
out  injuring  its  future  quaUties; 
and  tUs,  in  order  to  avoid  being 
obUged  to  multiply  moulds  indefi- 
nitely for  the  same  casting.  This 
last  desideratum  appears  to  be  dif- 
ficult. The  natural  cements,  which 
harden  almost  instantly  in  the  air 
and  in  the  vrater,  when  worked  up 
like  plaster  of  Paris,  are  subject  to 
the  inconvenience  of  being  tinged 
brown.  Such  as  are  fabricated 
artificially,  by  calcining  mixtures 
of  lime  and  clay  free  from  iron, 
do  not  stand  the  weather. 

Mortar  of  hydraulic  lime  may  be 
employed  as  a  plastic  substance  in 
a  multitude  of  cases,  in  which  the 
number  of  moulds  is  no  inconve- 
nience. Such  is  the  case  in  the  pre- 
paration of  artificial  stones  bearing 
mouldings,  vases,  or  ornaments  of 
any  kind  susceptible  of  formation 
by  the  rectilinear  or  circular  move- 
ment of  a  profile.  It  is  evident 
that  it  ¥nll  then  answer  to  set  the 
mould  in  a  trench,  and  run  the 
profile  along  the  clayey  paste,  pre- 
pared and  arranged  for  that  pur- 
pose. The  economy  which  such 
a  process  would  introduce  into 
ornamental  constructions  is  indeed 
incredible. 

Mortiaef  in  carpentry,  a  hole  cut  in  a 
piece  of  wood,  to  receive  a  corre- 
sponding  projection  formed  upon 
another  piece 

Mortise  and  Tenon,  The  following 
rules  may  be  referred  to  as  data  for 
the  workman  in  ordinary  practiee. 
The  tenon,  in  general,  may  be 
taken  at  about  one -third  of  the 
thickness  of  the  wood. 

When  the  mortise  and  tenon  are 
to  lie  horizontally,  as  the  juncture 
will  thus  be  unsupported,  the  tenon 
should  not  be  more  than  one-fifth 
of  the  thickness  of  the  stuff,  in 
order  that  the  strain  on  the  upper 
surface  of  the  tenoned  piece  may 
not  split  off  the  under-cheek  of  the 
mortise. 


MOR 


MOULDINGS. 


MOU 


When  the  piece  that  is  tenoned 
is  not  to  pass  the  end  of  the  mor- 
tised  piece,  the  tenon  should  be 
reduced  one-third  or  one-fourth  of 
its  breadth,  to  prevent  the  necessity 
of  opening  one  side  of  the  tenon. 
As  there  is  always  some  danger  of 
splitting  the  end  of  the  piece  in 
which  the  mortise  is  made,  the  end 
beyond  the  mortise  should,  as  often 
as  possible,  be  made  considerably 
longer  than  it  is  intended  to  remain; 
so  that  the  tenon  may  be  driven 
tightly  in,  and  the  superfluous  wood 
cut  off  afterwards. 

But  the  above  regulations  may 
be  varied,  according  as  the  tenoned 
or  mortised  piece  is  weaker  or 
stronger. 

The  labour  of  making  deep  mor- 
tises, in  hard  wood,  maybe  lessened, 
by  first  boring  a  number  of  holes 
with  the  auger  in  the  part  to  be 
mortised,  as  the  compartments  be- 
tween may  then  more  easily  be  cut 
away  by  the  chisel. 

Before  employing  the  saw  to  cut 
the  shoulder  of  a  tenon  in  neat 
work,  if  the  line  of  its  entrance  be 
correctly  determined  by  nicking 
the  place  with  a  paring  chisel, 
there  will  be  no  danger  of  the  wood 
being  torn  at  the  edges  by  the  saw. 

As  the  neatness  and  durability 
of  a  juncture  depend  entirely  on 
the  sides  of  the  mortise  coming 
exactly  in  contact  with  the  sides  of 
the  tenon,  and  as  this  is  not  easily 
performed  when  a  mortise  is  to  pass 
entirely  through  a  piece  of  stuff, 
the  space  allotted  for  it  should 
be  first  correctly  gauged  on  both 
sides.  One  half  is  then  to  be  cut 
from  one  side,  and  the  other  half 
from  the  opposite  side ;  and  as  any 
irregularities  which  may  arise  from 
an  error  in  the  direction  of  the 
chisel  will  thus  be  confined  to  the 
middle  of  the  mortise,  they  will  be 
of  very  little  hindrance  to  the  exact 
fitting  of  the  sides  of  the  mortise 
and  tenon.  Moreover,  as  the  tenon 
is  expanded  by  wedges  after  it  is 
driven  in,  the  sides  of  the  mortise 

298 


may,  in  a  small  degree,  be  inclined 
towards  each  other,  near  the  shoul- 
ders of  the  tenon. 

M-roof,  a  roof  formed  by  the  junction 
of  two  common  rooft  with  a  vallum 
between  them 

MosaiC'Workt  the  art  of  picturing  vnth 
small  pebbles  and  shells  of  various  j 
colours,  pieces  of  glass,  marble,  &c.  I 
cemented  on  a  ground  of  stucco 

Moique,  a  Mohammedan  temple 

3fo/t/;thatwhichsuggests  ahint  or  idea 
to  an  artist ;  also  the  hint  itself 

Motion.  The  cross-head,  cross-head 
guides,  and  blocks,  in  a  locomotive 
engine,  taken  as  a  whole,  are  called 
*  the  motion.' 

Motion  {laws  of),  A  body  must  con- 
tinue for  ever  in  a  state  of  rest,  or 
in  a  state  of  uniform  and  rectili- 
neal motion,  if  it  be  not  disturbed 
by  the  action  of  some  external 
cause.  The  alteration  of  motion 
produced  in  a  body  by  the  action 
of  any  external  force  is  always 
proportional  to  that  force,  and  in 
the  direction  of  the  right  line  in 
which  it  acts.  The  action  and  re- 
action of  bodies  on  one  another 
are  equal,  and  are  exerted  in  op- 
posite directions. 

Motion  of  bodies  on  inclined  planet. 
The  force  of  an  inclined  plane 
bears  the  same  proportion  to  the 
force  of  gravity  as  the  height  of 
the  plane  bears  to  its  length ;  that 
is,  the  force  which  accelerates  the 
motion  of  a  body  down  an  inclined 
plane,  is  that  fractional  part  of  the 
force  of  gravity  which  is  repre- 
sented by  the  height  of  the  plane 
divided  by  its  length. 

Mouldt  the  model  or  pattern  used  by 
workmen  as  a  guide  in  working 
mouldings  and  ornaments,  in  the 
casting  of  metal,  and  models  of 
machinery 

Mouldings,  a  term  applied  to  all  the 
varieties  of  outline  or  contour  given 
to  the  angles  of  the  various  subor- 
dinate parts  and  features  of  build- 
ings, whether  projections  or  cavi- 
ties, such  as  cornices,  capitals, 
bases,  door  or  window  jambs,  and 


MOU 


MOULDINGS. 


MOU 


heads,  &c  There  are  eight  sorts 
of  regular  mouldings,  viz.  the 
Ovolo,  the  Talon,  the  Cyma,  the 
Cavetto,  the  Toros,  the  Astragal, 
the  Scotia,  and  the  Fillet.  These 
mouldings  are  not  to  be  used  at 
hazard,  each  having  certain  situ- 
ations adapted  to  its  reception,  to 
which  it  must  always  be  applied. 
Thus  the  ovolo  and  talon,  from 
their  peculiar  form,  seem  intended 
to  support  other  important  mould- 
ings or  members;  the  cyma  and 
cavetto  being  of  weaker  contour, 
should  only  be  used  for  the  cover 
or  shelter  of  other  parts ;  the  torus 
and  astragal,  bearing  a  resemblance 
to  a  rope,  appear  calculated  to  bind 
and  fortify  the  parts  to  which  they 
are  applied ;  the  use  of  the  fillet 

6BEEK. 


and  sootiais  to  separate  one  mould- 
ing from  another,  and  to  give  a 
variety  to  the  general  profile.  The 
ovolo  and  talon  are  mostly  placed 
in  situations  above  the  level  of  the 
eye ;  when  below  it,  they  should 
only  be  applied  as  crowning  mem- 
bers. The  place  for  the  scotia  is 
universally  below  the  level  of  the 
eye.  When  the  fillet  is  very  wide, 
and  used  under  the  cyma  of  a  cor- 
nice, it  is  termed  a  corona ;  if  under 
a  corona,  it  is  called  a  band. 

The  curved  contours  of  mould- 
ings are  portions  of  either  circles 
or  ellipses. 

The  principal  mouldings,  and  the 
diflference  of  their  profiles  in  the 
Grecian  and  Roman  styles,  are  here 
exhibited. 

ROMAN. 


Echinus  or 
Ovolo. 


Cyma  Recto. 


Scotia. 


Torus. 


Mouldmg,  the  process  of  forming  a 
cavity  in  sand  or  loam,  in  order  to 
give  its  form  to  metal  which  is  ap- 


plied in  a  fiuid  state ;  an  ornamental 
cavity  in  wood,  stone,  or  other 
suitable  material 


299 


MOU 


MUSIC. 


MUS 


Mauntam-blue,  A  yery  beautiful  sub- 
stance of  this  kind,  a  carbonate  of 
copper,  both  blue  and  green,  is 
found  in  Cumberland.  None  of 
these  blues  of  copper  are,  however, 
durable ;  used  in  oil,  they  become 
green,  and,  as  pigments,  are  pre- 
cisely of  the  character  of  verditers. 

Mountam-ifreen  is  a  native  carbonate 
of  copper,  combined  with  a  white 
earth,  and  often  striated  ¥rith  veins 
of  mountain-blue,  to  which  it  bears 
the  same  relation  that  green  ver- 
diter  does  to  blue  verditer;  nor 
does  it  differ  from  these  and  other 
copper-greens  in  any  property  es- 
sential to  the  painter 

M.  S.f  an  abbreviation  commonly  used 
on  tomb -stones  or  monumental 
tablets,  for  the  Latin  words  Me- 
morue  Sacrum,  *  Sacred  to  the  Me- 
mory': the  letters  J.H.S.  are  often 
similarly  applied  in  sacred  edifices, 
for  Je8U8  Hommum  SahatoTf — 
*  Jesus  the  Saviour  of  Men.' 

Mtid-holeg,  the  covered  openings  in 
the  bottom  of  a  boiler  for  discharg- 
ing the  dirt  and  sediment 

Mu£plug9,  in  locomotive  engines, 
tapered  screw-plugs  fitted  into  con- 
venient parts  of  the  boiler,  to  admit 
of  its  being  washed  out  by  these 
plug-holes  when  necessary 

Mulberry-tree^  a  wood  of  great  variety, 
principally  frt)m  Rio  Janeiro,  and 
very  suitable  for  furniture 

MuUUm,  the  division  between  the 
lights  of  windows,  screens,  &c.  in 
Gothic  architecture :  the  styles  or 
upright  divisions  in  wainscoting 
are  also  sometimes  called  mullions 

Muk-Jermy,  a  machine  used  in  the 
manufacture  of  cotton  thread 

Mvn  (Cornish),  any  fdsible  metal 

MwuUck,  an  exceedingly  ponderous 
mineral,  whitish,  beautiful  and 
shining,  but  brittle.  It  is  abundant 
in  Cornish  and  Irish  mines. 

Jlfiffi»mat/-Aotwe,  a  strong,  properly 
fire-proof  apartment  in  public  or 
private  buildings,  for  the  preserva* 
tion  of  charters,  deeds,  seals,  &o. 

Mwmioni,  pieces  that  part  the  lights 
in  a  ship's  stem  and  quarter-gallery 


r,  in  house-building,  uinnght 
posts  that  divide  the  lights  in  a 
window-frame 

Mummy,  or  Eyyptian-brown,  is  a 
bituminous  substance,  combined 
vrith  animal  remains,  brought  from 
the  catacombs  of  Egypt,  where 
liquid  bitumen  was  employed  three 
thousand  years  ago  in  embalming, 
in  which  office  it  has  been  com- 
bined, by  a  slow  chemical  change, 
during  so  many  ages,  with  sub- 
stances which  give  it  a  more  solid 
and  lasting  texture  than  simple  as- 
phaltum;  but  in  this  respect  it 
varies  exceedingly 

Mural,  pertaining  to  a  wall ;  a  monu- 
mental tablet  affixed  to  a  vroll  is  a 
mural  monument 

Murometer,  an  instrument  to  measure 
small  spaces 

Muru»,  the  wall  of  a  Greek  city,  in 
contradistinction  to  Paries,  the  vrall 
of  a  house,  and  Maceria,  a  boundary 
wall 

Mueie.  This  word  is  derived  from 
the  Latin  murica,  and  this  again 
from  the  Greek  a4jective  moueUeot, 
which  signifies,  of  or  belonging  to 
the  Muses.  As  a  substantive,  the 
word  mourikoe,  or  in  Latin  mueieus, 
a  musician,  means  also  a  poet  or 
an  orator;  and  in  the  feminine 
gender  signifies  the  liberal  arts,  but 
especially  music,  poetry,  and  elo- 
quence. The  ancients,  therefore, 
understood  by  music  far  more  than 
has  been  attributed  to  it  for  some 
ages  past.  Music  is  now  considered 
as  the  language  of  agreeable  sounds, 
and  is  both  a  science  and  an  art. 
As  a  science,  it  teaches  the  theory 
of  musical  sounds,  their  production 
by  the  vibrations  of  the  air,  the 
ratio  of  these  vibrations,  and  also 
their  times;  likewise  the  various 
phenomena  connected  with  musical 
sounds,  the  causes  of  discords,beats, 
&c.,  as  well  as  the  lengths  of  mu- 
sical strings  and  pipes.  The  ma- 
thematical theory  of  music  is  part 
of  the  science  of  acoustics,  or 
phonics,  and  is  therefore  one  of  the 
high  mechanical  sciences.    As  an 


300 


MUS 


NAOS. 


NAP 


art,  music  teaches  the  practical  use 
of  the  science ;  the  scales  or  gamuts 
of  sounds  in  a  fixed  succession »  at 
fixed  intervals  from  each  other ;  the 
permutations  of  their  sounds;  form- 
ing an  immense  yariety  of  melodies. 
It  teaches  also  the  combination  of 
these  sounds  according  to  certain 
received  laws,  forming  thereby  the 
most  agreeable  sensations  on  the 
ear,  by  producing  a  great  variety  of 
chords,  composed  of  concordant 
sounds  alone,  or  of  a  judicious  ad- 
mixture of  concordant  and  dissonal 
sounds.  Practical  music  teaches 
also  the  use  and  performance  of  the 
several  instruments  of  music,  as 
also  their  peculiar  functions ;  and 
herein  is  embraced  the  human  voice, 
the  most  perfect  and  beautiful  of 
all  musical  instruments.  Music, 
therefore,  is  divided  into  two  grand 
parts,  viz.  theoretical  or  scientific, 
and  practical ;  the  former  treating 
of  the  purely  philosophical  branch 
mathematicidly,  the  latter  being 
confined  solely  to  the  production  of 
musical  compositions,  and  their  per- 
formance. I^ctical  music  consists 
of  several  species,  the  highest  of 


which  is  the  ecclesiastical;  then 
follow  the  oratorio,  opera,  military, 
chamber,  and  ball-room  species ;  and 
is  divided  into  vocal  and  instru- 
mental music,  each  of  these  being 
variously  subdivided. 

Musnudf  in  Persia,  a  throne  or  chair 
of  state 

Mtuiaibt  a,  wood  from  the  Brazils, 
inferior  to  rose  wood,  but  harder ; 
used  at  Sheffield  for  the  handles  of 
glaziers'  and  other  knives,  &c. 

Mutule,  a  projecting  block  worked 
under  the  corona  of  the  Doric  cor- 
nice, in  the  same  situation  as  the 
modillions  in  the  Corinthian  and 
Composite  orders ;  it  is  often  made 
to  slope  downward  towards  the  most 
prominent  part,  and  has  usually  a 
number  of  small  guttae  or  drops, 
worked  on  the  under  side 

Mynchen/t  the  Saxon  name  for  a  nun- 
nery :  nuns  were  sometimes  called 
Mynchies 

MyoparOy  a  small  piratical  craft,  em- 
ployed by  the  Saxon  corsairs 

Myriady  the  number  of  10,000 ;  pro- 
verbially any  great  number 

Myriameire,  a  French  measure  of 
10,000  metres 


NAI 

Nails,  used  in  building,  are  small 
metallic  spikes  serving  to  bind  or 
fasten  the  parts  together.  There 
are  several  kinds  of  nails,  called  by 
numerous  names.  In  the  middle 
ages,  nails  were  frequently  used 
much  ornamented,  of  which  there 
are  several  very  beautiful  existing 
specimens,  particularly  in  church 
doors  and  the  gates  of  large  man- 
sions. 

Nakedt  of  a  column  or  pilaster,  the 
surface  of  the  shaft  where  the 
mouldings  are  supposed  to  project 

Nakedf  of  a  wall,  the  remote  face 
whence  the  projectures  take  their 
rise.  It  is  generally  a  plain  sur- 
face, and  when  the  plan  is  circular, 
the  naked  is  the  surface  of  a  cy- 
linder, with  its  axis  perpendicular 
to  the  horizon. 

301 


NAP 

Naked  flooring^  in  carpentry,  the 
whole  assemblage  or  contignation 
of  timber-work  for  supporting  the 
boarding  of  a  floor  on  which  to 
walk.  Naked  flooring  consists  of 
a  row  of  parallel  joists,  called  fioor- 
joists. 

NaoSt  the  chamber  or  enclosed  apart- 
ment of  a  Greek  temple.  The  part 
of  the  temple  which  stood  before 
the  naos,  comprehended  between 
the  wall  and  the  columns  of  the 
portico,  was  called  the  pronaos; 
while  the  corresponding  part  be- 
hind was  called  the  posiicum, 

Naples  yellow  is  a  compound  of  the 
oxides  of  lead  and  antimony,  an- 
ciently prepared  at  Naples  under 
the  name  of  Grallolina ;  it  is  sup- 
posed also  to  have  been  a  native 
production  of  Vesuvius  and  other 


NAP 


NASMYTH'S  MACHINES. 


NAT 


volcanoes,  and  is  a  pigpient  of  de- 
seiredly  considerable  reputation. 
It  is  not  so  Tivid  a  colour  as  patent 
yellow  and  turbith  mineral,  but  is 
variously  of  a  pleasing  light,  warm, 
golden -yellow  tint.  Like  most 
other  yellows,  it  is  opaque,  and 
in  this  sense  is  of  good  body.  It 
is  not  changed  by  the  light  of  the 
snn,  and  may  be  used  safely  in  oil 
or  varnish,  under  the  same  man- 
agement as  the  whites  of  lead; 
but  like  these  latter  pigments  also, 
it  is  liable  to  change  even  to  black- 
ness by  damp  and  impure  air  when 
used  as  a  water-colour,  or  unpro- 
tected by  oil  or  varnish. 

Naphtha^  a  species  of  nuneral  oil  or 
fluid  bitumen,  now  oommoidy  used 
for  lamps 

NarthejTf  a  division  in  the  early 
Christian  churches  in  which  th^ 
catechisms  were  said,  and  peni- 
tents admitted;  it  was  near  the 
entrance,  and  separated  firom  the 
rest  of  the  church  by  a  railing  or 
screen 

NasmyW  8  patent  direet-aetiontteam' 
hammer  is  employed  instead  of  the 
old  helves  or  lift-hammers,  and  is 
worked  by  a  connected  high-pres- 
sure steam  engine,  which  raises  the. 
hammer  to  any  required  height 
within  its  vertical  range  of  motion, 
and  in  which  it  is  guided  by  two 
planed  guides.  On  the  escape  of 
the  steam,  when  the  valve  of  the 
cylinder  is  opened,  the  hammer 
falls  on  the  work  that  lies  on  the 
anvil  with  the  full  force  due  to 
gravity,  without  scarcely  any  loss 
from  friction.  The  instant  the 
hammer  has  given  its  blow,  the 
steam  is  again  let  in  under  the 
piston,  and  the  same  action  is  re- 
peated with  ease  and  rapidity. 

NaamytKs  steam  pile-driving  engine. 
There  are  two  grand  or  important 
features  of  novelty  in  this  pile- 
driving  engine,  compared  with  all 
former  contrivances  for  the  like 
purpose.  In  the  first  place,  by  the 
employment  of  the  steam-hammer 
action,  the  steam  is  made  to  act 

3^2 """^ 


direct  in  raisiBg  up  and  letting  fall 
the  hammer,  or  monkey,  without 
the  intervention  of  any  rotatory  mo- 
tion; while,  in  the  second  place, 
another  graiid  feature  consists  in 
the  emptoyment  of  the  pile  about 
to  be  driven,  or  raised  up  and 
planted  in  its  situation  by  the  ma- 
chine, by  means  of  a  windlass 
worked  by  a  small  detached  steam 
engine* 

Some  conception  of  the  rapidity 
with  which  piles  are  driven  by  this 
machine  may  be  formed,  when  it 
is  stated  that  a  pile  measuring  60 
feet  in  length,  and  14  inches 
square,  can  be  driven  45  feet  into 
stiff  soil,  down  to  the  rock  below,  in 
four  minutes;  and  such  is  the  good 
effect  resulting  £rom  the  blows  by 
being  given  by  a  great  mass  of 
30  cwt.  striking  quickly,  but  with 
small  velocity  of  actual  impact,  that 
the  head  ojf  the  pile  requires  no 
hoop,  and  presents,  after  being 
driven,  a  neater  appearance  than  it 
had  when  it  was  first  placed  under 
the  hammer. 

Natural  bedt  of  stone  are  the  surfaces 
from  which  the  laminae  are  sepa- 
rated. It  is  all  important  for  the 
duration  of  stone  walls,  that  the 
laminae  should  be  placed  perpendi- 
cular to  the  face  of  the  work,  and 
parallel  to  the  horizon. 

Natural  Philosophy  takes  an  exten- 
sive range,  embracing  the  study  of 
the  collection  of  created  beings 
and  objects,  and  of  those  laws  by 
which  they  are  governed,  all  of 
them  expressed  in  the  term  Nature. 
Natural  objects  are  separated  into 
two  grand  classes,  the  organic  and 
inorganic;  the  former  being  dis- 
tinguished by  vital  power  <Mf  life- 
organic  bodies  admit  of  a  marked 
distinction  into  anunals  and  plants ; 
the  science  of  Zoology  describing 
and  classifying  the  one,  and  that  of 
Botany  the  other.  These  sciences 
admit  of  many  subdivisions,  and 
collectively  with  Mmeralogy,  that 
of  Natural  History : 
1.  Geology,  the  science  which  has 


NAT 


NAVE. 


NEB 


for  its  object  the  observation  and 
description  of  the  structure  of  the 
external  crust  of  the  globe ;  Mine- 
ralogy taking  account  only  of  the 
separate  items  of  which  the  earth's 
crust  is  composed.  2.  Chemistry, 
which  may  be  regarded  as  atomic 
anatomy,  its  object  being  to  de- 
compose bodies,  to  study  the  proper- 
ties of  their  elements,  and  the  laws 
of  combination.  3.  Physics,^  or 
NaturalPhilosophy,  which  considers 
the  general  properties  of  all  bodies. 
Natural  philosophy  is  again  sub- 
divided into  many  distinct  sciences. 
The  mutual  action  of  forces  and 
masses  of  matter  produces  in  the 
latter  either  eqmHbrium  or  motion, 
and  hence  arise  those  two  divisions 
of  sciences,  called  Statics  and  Dy- 
namics, which  are  again  divided 
into  Stereo -statics  and  Stereo- 
dynamics,  as  applied  to  solids; 
Hydrostatics  and  Hydrodynamics, 
as  applied  to  liquids ;  Electro-statics 
and  Electro-dynamics,  as  applied  to 
Electricity.  The  application  of 
statics  and  dynamics  to  air  and 
other  gaseous  fluids  is  called 
Pneumatics.  The  application  of 
dynamics  to  the  arts  of  life  has 
led  to  the  composition  and  arrange- 
ment of  the  various  machines  for 
assisting  the  labour  of  man :  this 
branch  is  called  Mechanics.  The 
construction  and  performance  of 
the  various  machines  to  raise  water, 
or  which  are  driven  by  the  motion  of 
that  fluid,  belong  to  hydronamics, 
while  the  construction  of  works  de- 
pending on  the  equilibrium ofhquids 
belongs  to  hycbrostatics.  Those 
machines  which  are  driven  by  the 
wind  depend  on  the  application  of 
pneumatics ;  and  all  the  varied 
phenomena  of  the  atmosphere 
arising  from  the  action  of  heat, 
light,  electricity,  and  moisture, 
form  the  science  of  Meteorology. 
The  phenomena  of  heat  and  elec- 
tricity also  form  separate  sciences; 
the  latter  admitting  of  Ave  divisions, 
viz.  electricity,  magnetism,  galvan- 
ism or  voltaic  electricity,  thenno- 

303  ^'  


electricity,  and  animal  electricity. 
The  phenomena  of  light,  although 
included  in  the  term  Optics,  are 
varied ;  namely,  perspective,  catop- 
trics, dioptrics,  chromatics,  physical 
optics,  and  polarization ;  to  which 
may  be  added  actino-chemistry. 

Nttumachiaf  among  the  Greeks,  a 
sea-fight;  a  spectacle.  The  term 
was  also  applied  to  a  circus  encom- 
passed with  seats  and  porticoes, 
the  pit  of  whicdi,  serving  as  an 
arena,  was  filled  with  water  by 
means  of  pipes,  for  the  exhibition 
of  sea-fights. 

Naupegrus,  a  shipwright 

Nautical,  periaining  to  ships  or  sailors 

Naval  Jrchitecture,  the  art  of  de- 
signing and  constructing  ships  and 
vessels  for  the  purposes  of  naviga- 
tion 

Navale,  a  ship-dock  or  dockyard 

Navalia,  ship-building  docks  at  Rome, 
where  also  ships  were  laid  up  and 
refitted 

NavarchvSt  among  the  ancients,  the 
name  of  a  commander  or  admiral 
of  a  fleet 

NavCf  the  body  of  a  church  west  of 
the  choir,  in  which  the  general 
congregation  assemble.  In  large 
buildings  it  consists  of  a  central 
division,  with  two  or  more  aisles ; 
and  th^re  are  frequently,  in  foreign 
structures,  several  small  chapels  on 
the  sides  beyond  the  aisles.  In 
mechanics,  the  central  part  of  a 
wheel. 

Navel-hoods,  in  ship-building,  pieces 
of  plank,  or  thick  stuff,  wrought 
above  and  below  the  hawse-holes 

Navia,  in  church  furniture,  a  metal 
dish  or  vessel  to  contsun  frankin- 
cense 

Neap,  low,  decrescent;  a  term  applied 
to  the  tides  which  happen  when 
the  moon  is  in  the  middle  of  her 
second  and  fourth  quarters.    The 

'  highest  spring-tide  is  three  days 
after  the  full  or  change ;  the  lowest 
neap-tide  is  four  days  before  the 
full  or  change. 

Nebule  moulding,  an  heraldic  term. 
In  architecture,  an  ornament  of  the 


NEC 


NICHE. 


NOG 


zigzag  form,  but  without  angles: 
it  is  chiefly  found  in  the  remains  of 
Saxon  architecture!  in  the  archi- 
volts  of  doors  and  windows. 

Neck  of  a  eapitalf  the  space  between 
the  channelures  and  the  annulets 
of  the  Grecian  Doric  capital.  In 
the  Roman  Doric  it  is  the  space 
between  the  astragal  and  the  an- 
nulet. 

Neck'tnouldi  in  architecture,  a  small 
convex  moulding  surrounding  a 
column  at  the  junction  of  the  shaft 
and  capital 

Necrology y  an  obituary  formerly  kept 
in  churches  and  monasteries 

Needle^  or  Nailf  in  mining,  a  long 
taper  piece  of  copper  or  iron,  with 
a  copper  point;  used  ^vhen  stamp- 
ing the  hole  for  blasting,  to  make 
by  its  insertion  an  aperture  for  a 
fusee  or  train 

Needle-work,  a  term  anciently  used 
for  the  frame-work  of  timber  and 
plaster  in  old  houses 

Neoy  a  Greek  term,  to  spin  or  twist  a 
number  of  separate  fibres  of  wool  or 
flax  into  a  single  thread 

Neplus  ultra  (Latin),  the  extreme  of 
any  thing 

NervureSf  nerves  or  branches,  a  term 
applied  by  Prof.  Willis,  of  Cam- 
bridge,  to  the  ribs  of  a  vaulted  roof 
which  bound  the  sides  of  any 
groined  compartment 

Net,  or  Neat,  in  commerce,  that  which 
is  pure  and  unadulterated;  the 
weight  of  any  package  after  the 
tare  has  been  deducted :  most  com- 
monly, but  improperly,  vmtten  nett 

Newel,  the  central  column  round 
which  the  steps  of  a  circular  stair- 
case wind;  the  principal  post  at 
the  angles  and  foot  of  a  stair- 
case.  In  the  Tudor  and  Elizabe- 
than residences  very  beautiful  ex- 
amples exist,  adding  much  to  the 
beauty  of  the  staircase. 

Niche,  in  architecture,  a  cavity  or 
hollow  place  in  the  thickness  of  a 
wall,  in  which  to  place  a  figure,  a 
statue,  vase,  or  ornament.  Niches 
are  made  to  partake  of  all  the  seg- 
ments under  a  semicircle :  they  are 


sometimes  at  an  equal  distance 
from  the  frt)nt,  and  parallel  or 
square  on  the  back  with  the  frx>nt 
line,  in  which  case  they  are  called 
square  recesses,  or  square  niches. 
Occasionally  small  pediments  were 
formed  over  them,  supported  on 
consoles,  or  small  columns  or  pi- 
lasters placed  at  the  sides  of  the 
niches.  Anciently  they  were  used 
in  ecclesiastical  buildings  for  sta- 
tues and  shallow  square  recesses. 
The  ruins  of  Palmyra  exhibit  niches 
of  various  kinds.  Within  the  por- 
tico of  the  temple  of  the  Sun  there 
are  two  niches,  &c. 

Niche,  angular,  one  formed  in  the 
comer  of  a  building 

Niche,  in  carpentry,  the  wood-work 
to  be  lathed-over  for  plastering. 
The  usual  constructions  of  niches  in 
carpentry  are  those  with  cylindrical 
backs  and  spherical  heads,  called 
cyUndro-spheric  niches,  the  execu- 
tion of  which  depends  upon  the 
principles  of  spheric  sections. 

Niche,  ground,  that  which,  instead  of 
bearing  on  a  massive  base  or  dado, 
has  its  rise  from  the  ground, — as 
the  niches  of  the  portico  of  the 
Pantheon  at  Rome :  their  ordinary 
proportion  is,  two  diameters  in 
height,  and  one  in  width.  Round 
or  square  niches  are  also  formed. 

Nigged  ashlar,  stone  hewn  with  a  pick 
or  pointed  hammer,  instead  of  a 
chisel;  used  principally  at  Aber- 
deen for  the  hewing  of  the  hard 
granite 

Nitrate  of  lime,  nitric  acid  in  combi- 
nation with  lime  for  a  base,  abound- 
ing in  the  mortar  of  old  buildings 

Nitrates,  compounds,  or  salts,  formed 
by  the  combination  of  nitric  add 
with  alkalies,  earths,  and  metallic 
oxides 

iVt/r«, common  saltpetre;  in  chemistry, 
nitrate  of  potash 

Nodus,  anciently,  in  our  cathedrals,  a 
knot,  key-stone,  or  boss 

Nog,  in  ship-building,  a  treenail  driven 
through  the  heel  of  the  shores  which 
support  a  ship  on  the  slip 

iVb^f,  blocks  of  wood  cut  to  the  form 


304 


NOG 


NORMAN  ARCHITECTURE. 


NOR 


and  size  of  bricks,  and  inserted  in 
the  interior  walls  of  apartments  as 
holds  for  the  joinery 

Nogs  or  Nays,  in  miningi  square  pieces 
of  wood  piled  on  each  other  to  sup- 
port the  roof  of  a  mine  . 

Noggmgy  a  kind  of  brick-work  carried 
up  in  panels  between  quarters 

Nogging'pieces  are  horizontal  boards 
placed  in  brick-nogging,  nailed  to 
the  quarters,  in  order  to  strengthen 
the  brick-work 

NomadeSf  in  antiquity,  wandering, 
rude,  or  savage  tribes 

Nomenclature,  the  art  of  naming ;  a 
vocabulary  or  dictionary  of  techni- 
cal language  peculiar  to  any  art  or 
science 

Nonagotif  a  figure  of  nine  sides  and  of 
as  many  angles 

Non- condensing   Engines   are  those 
made  without  that  part  of  the  ma- 
chine called  a  condenser,  and  with- 
out those  contrivances  essential  to 
the  ordinary  construction   of  en- 
gines that  condense  the  vapour  into 
fluid.    In  non-condcDsing  engines 
the  steam  escapes  into  the  atmo- 
sphere, after  having  acted  upon  the 
piston.    The  effect  is  measured  by 
the  excess  of  the  pressure  of  the 
steam  upon  the  piston,  less  the 
friction  of  the  engine  above  the 
pressure  of  the  atmosphere. 
Nmi-conductorSt  substances  through 
which  the  electric  fluid  passes  with 
considerable  difficulty  or  not  at  aU ; 
such  as  glass,  resin,  sulphur,  silk, 
hair,  wool,  the  air,  &c. ;  but  these 
become  electric  by  friction 
NoneSf  in  the  Roman  calendar,  the 
fifth  day    of   January,  February, 
April,  June,  August,  September, 
November,    December;    and   the 
seventh  of  March,  May,  July,  and 
October 
Noria,  an  hydrauUc  machine,  com- 
mon in  Spain  for  raising  water.  The 
engine  consists  of  a  vertical  wheel 
of  20  feet  diameter,  on  the  circum- 
ference of  which  are  fixed  buckets, 
for  the  purpose  of  raising  water  out 
of  wells,  &c.,  communicating  with 
a  canalbelow,  and  emptying  it  into  a 

305 


reservoir  above,  placed  by  the  side 
of  the  wheel.  The  buckets  have  a 
lateral  orifice,  to  receive  and  dis- 
charge the  wftter.  The  axis  of  the 
wheel  is  embraced  by  four  small 
beams,  crossing  each  other  at  right 
angles,  tapering  at  the  extremities, 
and  forming  eight  little  arms.  This 
wheel  is  near  the  centre  of  the 
horse-walk,  contiguous  to  the  ver- 
tical axis,  into  the  top  of  which  the 
top  beam  is  fixed;  but  near  the 
bottom  it  is  embraced  by  four  Uttle 
beams,  forming  eight  arms  similar 
to  those  above  described,  on  the 
axis  of  the  water-wheel.  In  the 
movement  of  the  horse  or  mule, 
these  horizontal  arms,  acting  on 
cogs,  take  hold,  each  in  succession, 
of  those  arms  which  are  fixed  on 
the  axis  of  the  water-wheel,  and 
keep  it  in  rotation. 

Nomuij  a  square  for  measuring  right 
angles,  used  by  carpenters,  ma- 
sons, and  other  artificers,  to  make 
their  work  rectangular 

Normal  Hne,  in  geometry,  a  phrase 
used  for  a  perpendicular  line 

Norman  Architecture,  In  Normandy, 
in  the  tenth  century,  when  the 
Normans  occupied  Neustria,  the 
churches  in  other  parts  of  France 
were  in  imitation  of  the  Roman 
style.  The  plan  of  the  buildings 
came  from  Rome,  and  the  round 
arches,  the  pillars,  and  the  mould- 
ings, which  were  employed  in  their 
construction,  had  the  same  origin. 
But  the  corrupt  taste  of  a  less 
civilized  people  covered  the  capitals 
and  the  portals  with  a  crowd  of 
such  appalling  images  as  a  vrild 
fancy  was  likely  to  suggest,  and  a 
rude  hand  to  portray. 

The  Normans,  adopting  the 
habitual  plan  and  the  established 
style,  rejected  the  meretricious  ac- 
cessories, and  resolved  to  trust  for 
success  to  the  two  great  principles 
of  size  and  elevation.  The  oldest 
of  the  Norman  churches  are  the 
plainest,  but  even  these  aspire  to 
dimensions  which  could  not  fail  to 
command  admiration.    Their  cha- 


NOR 


NORMAN  ARCHITBCTURE. 


NOR 


racter  is  severe  but  sublime.  At 
the  same  time,  the  Normans  had 
the  boldness  to  insist  upon  an 
addition  to  their  draiches,  which 
is  admitted  to  be  the  grandest 
feature  and  the  chief  ornament 
of  ecclesiastical  buildings — the 
central  tower.  Towers  had,  for- 
tunately, become  an  integral  part 
of  churches  before  the  Normans 
began  to  build  in  Neustria,  but  the 
few  towers  which  at  that  lime  ex- 
isted in  other  parts  at  Vnnce  only 
adorned  the  western  end.  Size, 
elevation,  simpticity,  and  strength, 
together  with  the  central  tower, 
are  the  architectural  peculiarities 
to  which  the  Normans,  as  contra- 
distinguished from  the  Franks,  pos- 
sess undeniable  claims. 

Norman  workmanship  was,  at 
first,  remarkable  only  for  its  solidity. 
The  walls  were  often  built  of  rub- 
ble,faced  with  small  squared  stones, 
— a  manner  of  building  which  had 
been  copied  from  the  works  which 
the  Romans  had  left  behind  them 
in  France.  The  pillars  Were,  of 
course,  composed  of  larger  blocks. 
By  degrees,  and  in  buildings  of 
importance,  larger  blocks  were  em- 
ployed in  the  walls ;  but  the  joints 
were  wide,  and  the  mortar  was 
coarse.  In  the  time  of  William 
the  Conqueror,  greater  neatness 
was  accomplished ;  the  stones  were 
squared,  and  the  courses  regular; 
but  the  joints  were  still  rather 
wide,  and  the  mortar  unsifted. 

Another  mode  of  construction 
was  with  long,  narrow  stones, 
which  were  placed,  not  in  hori- 
zontal  courses,  but  alternately  in- 
clined to  the  right  and  left.  This, 
from  the  appearance  it  presented, 
was  called  the  herring-bone  fashion. 
It  did  not  remain  in  use  much 
after  the  eleventh  century. 

The  Norman  walls  were  of  great 
thickness,  and  were  filled  up  with 
small  stones,  amongst  which  mortar 
was  poured  in  hot.  This  was  called 
grouting  s  and  in  time  the  whole 
mass  so  hardened  together  as  to 

306 


acquire  the  consistence  and  strength 
of  a  solid  rock.  Such  walls  stood 
in  no  need  of  buttresses,  through 
the  means  of  which  more  advanced 
science  afterwards  obtainedan equal 
amount  of  power  at  less  labour  and 
less  expense.  Buttresses,  however, 
appear  on  the  exterior  of  early  Nor- 
man buildings,  but  seem  to  have 
been  introduced  only  to  relieve  the 
baldness  of  the  surface.  They  pro- 
ject so  slightly  that  they  can  add 
but  little  support.  In  early  Nor- 
man buildings  the  buttresses  never 
rise  above  the  cornice. 

The  plan  of  the  early  Norman 
churches  is  always  that  of  the 
basilica,  with  a  semicircular  recess 
at  the  end,  which  recess  formed 
the  choir.  The  larger  churches 
have  transepts  and  side  aisles  which 
are  divided  from  the  nave  by  ar- 
cades. The  small  churches  have 
often  neither  side  aisles  nor  tran- 
septs. The  arches  of  the  nave 
either  rest  on  piers,  to  which  half- 
pillars  are  attached,  or  on  single 
pillars,  but  hardly  ever  on  those 
huge  cylindrical  piers  which  are 
commonly  seen  in  the  Norman 
churches  of  England.  Indeed,  the 
thick  cylindrical  piers  of  Eng^nd 
are  scarcely  to  be  met  with  in  all 
France,  except  in  one  or  two  crypts, 
where  the  known  superincumbent 
weight  justifies  the  preference  of 
strength  to  beauty. 

In  the  churches  of  France,  single 
pillars  preceded  piers;  the  exact 
reverse  of  what  might  have  been 
expected,  were  it  not  recollected  to 
what  an  extent  and  degree  France 
had  become  Roman,  previous  to 
the  inroad  of  the  Northern  con- 
.querors.  The  pillars  have  always 
capitals,  which,  at  first,  were  per- 
fectly plain ;  but,  from  the  begin- 
ning of  the  eleventh  century,  were 
enriched  with  different  kinds  oi 
foliage,  to  a  certain  degree  depart- 
ing from,  but  still  seelang  to  imi- 
tate, the  Roman  models.  The  half- 
pillars,  which  are  attached  to  the 
ends  of  the  piers,  are  always  set 


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NORMAN  ARCHITECTURE. 


NOR 


iMck in  recesses,  or  sinks;  tbe  same 
is  the  case  with  the  small  pOlars  on 
the  outside  of  the  windows,  as  also 
with  thoae  of  tilie  ptMrtals.  This  is 
a  characteristic  between  the  Nor- 
man style  and  the  Roman-^he 
Norman  pillars  are  recessed;  the 
Roman  project. 

The  windows  are  aiwajrs  round- 
headed,  and  undivided ;  and,  exter- 
nally, have  on  each  side  a  small 
recessed  pillar,  which  supports  an 
impost  and  moulding. 

In  the  gable,  over  the  entrance 
door  of  churches,  a  small  circular 
window  is  sometimes  introduced. 

The  vnndows  of  castles  and  of 
domestic  buildings  are  usually  di- 
vided by  a  single  shaft. 

The  portals  are  round-headed, 
and  were  gradually  enriched  by  an 
increasing  number  of  semicircular 
mouldings.  The  most  common 
mouldings  are  the  billet,  the  nail- 
head,  the  chevron,  the  zigzag  or 
embattled  frette,  hatchet,  nebule, 
star,  rope,  beak-head,  dog-tooth, 
and,  occanonally,  different  sorts  of 
foliage,  as  the  vine,  the  bay,  the 
ivy,  &c.  {See  Frontispiece.) 

The  external  coniioe,  undw  the 
eaves  of  churches,  was  sometimes 
a  moulding  describing  a  series  of 
semicircles,  under  a  projecting 
course,  and  sometimes  a  series  of 
blocks.  The  ornamented  corbels, 
on  the  exterior  of  churdies,  were 
adopted  by  the  Normans  before 
imagery  was  admitted  into  the  in- 
terior of  the  edifice. 

The  roofs  of  ttie  early  Nonnan 
churches  were  of  wood,  except  the 
part  over  the  semicircular  chancel, 
which  from  the  first  was  vaulted 
with  stone.  The  side  aisles  were 
also  vaulted  with  st<me ;  as  were, 
sometimes,  the  comparatively  small 
naves  of  village  churches.  The 
vaulting  vras  composed  either  of 
small  stones  let  into  a  bed  of  mor- 
tar or  of  tufa,  or  of  a  light  caka- 
reons  stone,  which  is  found  in  many 
parts  of  Normandy.  The  most 
ancient  vaulting  is  without  ribs, 

307 


and  the  most  andent  ribs  are  with- 
out mouklings. 

The  dome  vaulting  over  the  side 
aisles  of  the  abbey  church  at  Bemay 
is  the  only  specimen  of  the  kind  in 
Normandy. 

The  first  and  purest  Norman 
style  prevailed  till  the  latter  part 
of  the  reign  of  Willvun  the  Con- 
queror, from  the  early  part  of  the 
tenth  till  nearly  the  end  of  the 
eleventh  century. 

The  abbey  church  of  Bemay, 
begun  in  the  first  half  of  the 
eleventh  century,  is  the  oldest 
Nonnan  building  of  any  conse- 
quence which  remains  in  its  pri-. 
mitive  form.  The  architecture  of 
the  interior  is  plain  to  baldness, 
but  the  dimensions  are  imposing. 

The  abbey  churches  of  Jumieges  • 
and  Cerisy  were  begun  in  the  &%t : 
half  of  the  eleventh  century.    The ; 
Nonnan  portions  of  the  cathedral, 
and  of  the  church  of  St.  Taurin,  at 
Evreux,  as  also  of  the  church  of 
Mont  St.  Michel,  belong  to  the 
same  period. 

St.  Georges  de  Boscherville,  and  j 
the  two  great  churches  at  Caen,; 
arc  splendid  examples  of  the  ar- : 
chitecture  of  the  time  ei  William 
the  Conqueror. 

In  all  these  buildings  the  dia- 
meter of  simplicity  is  preserved, 
but  some  ornament  in  the  details 
b^jins  to  make  its  appearance  be- 
frire  the  dose  of  the  Conqueror's  | 
rdgn,  as,  for  instance,  in  the  em- 
battled frette  moulding  round  the 
ardies  of  the  nave  of  Matilda's 
church  at  Caen,  in  some  parts  of 
St.  Georges  de  Boscherville,  and 
other  places. 

The  fiorid  Norman  was  already 
developed  in  the  early  part  of  the 
twelfth  century.  Of  this  style  a 
rich  specimen  is  afforded  in  the 
arcade  of  the  nave  at  Bayeux. 
The  arches  are  ornamented  with  a 
multiplidty  and  variety  of  mould- 
ings of  intricate  design  and  elabo- 
rate execution. 

Another  spedmen  of  the  fiorid 


NOR 


NORMAN  (ANGLO)  ARCHITECTURE. 


NOR 


] 


Norman  exists  in  the  ndghbour- 
hood  of  Bayeux,  in  the  church  of 
St.  Gabriel,  built  by  Robert  of 
Gloucester  (1128). 

The  abbey  church  of  Monti- 
villiers  (1117),  and  the  church  at 
Graville,  are  instances  of  the  florid 
style  in  all  its  exuberance. 
Norman  Architecture  in  England,  Of 
the  architecture  which  existed  in 
this  country  previous  to  the  intro- 
duction of  the  Norman  there  are 
no  certain  vestiges.  The  most 
competent  authorities  have  decided 
that  hardly  any  thing  which  can 
be  proved  to  be  Saxon  remains  in 
existence.  Parts  of  a  few  churches, 
which  have  all  the  marks  of  a  very 
remote  antiquity,  and  of  which  the 
style  differs  materially  from  the 
Norman,  may  be  suspected  to  be 
Saxon.  Their  distinguishing  fea- 
tures are  a  ruder  imitation  of  the 
Roman,  projecting,  instead  of  re- 
cessed pillars,  and  the  combination 
of  diagonal  with  perpendicular 
forms  in  the  external  ornaments  of 
towers.  Such  is  the  case  at  the 
old  church  of  Barton,  in  Lincoln- 
shire, and  at  Earrs  Barton^  in 
Northamptonshire. 

Some  persons  have  imagined 
that  the  generality  of  the  Saxon 
churches  were  merely  timber  build- 
ings, but  this  appears  to  be  a 
mistake;  for  in  Domesday  Book, 
which  takes  note  of  1 700  churches, 
one,  and  only  one,  is  specified  as 
being  built  of  wood ;  and  Henry  of 
Huntingdon,  speaking  of  a  parti- 
cular  church,  says,  "It  was  not 
built  of  stone,  but  of  wood,  and 
covered  with  reeds,  as  is  the  custom 
in  Scotland;''  demonstrating  that 
it  was  not  the  custom  in  Eng- 
land. 

Not  only  were  the  Saxon  churches 
not  merely  timber  buildings,  but 
some  of  them  were  constructed  at 
a  considerable  expense,  and  with 
much  architectural  ornament. 

In  the  seventh  century,  a  church 
was  built  at  Lincoln,  which  Bede 
says  was  of  stone,  and  of  good 

308  ^ 


workmanship.  The  church  of  the 
monastery  of  Wearmouth  -was 
erected  in  675,  by  Abbot  Benedict 
Biscopius,  a  noble  Northumbrian, 
who,  at  twenty-five  years  of  age, 
detached  himself  from  the  service 
of  King  Oswy,  and  embraced  a  re- 
ligious life.  He  brought  over 
masons  from  France  to  build  his 
chjurch  in  the  Roman  manner,  and, 
when  the  building  was  nearly 
finished,  he  procured  artificers  from 
the  same  country,  skilled  in  the 
mystery  of  making  glass,  to  glaze 
the  windows. 

The  conventual  church  of  Ripen, 
and  the  cathedral  church  of  Hex- 
ham, were  both  built  by  Wilfrid, 
Bishop  of  York,  in  the  second  half 
of  the  seventh  century ;  and  were 
both  constructed  of  stone,  and 
supported  by  pillars  and  arches. 
WilMd  also  imported  builders 
and  artists  from  abroad — from 
Rome,  Italy,  France,  and  other 
countries* 

In  the  eighth  century,  the  mo- 
nastery of  Croyland  was  built  by. 
Ethelbald,  King  of  Mercia;  and  the 
church  of  St.  Peter  at  York  was 
rebuilt  by  Archbishop  Albert,  and 
consecrated  just  before  his  death, 
which  took  place  in  780.  Alcuin 
describes  this  church  as  having 
pillars,  arches,  and  porticoes. 

In  the  ninth  century,  the  pro- 
gress  of  the  arts  was  interrupted 
by  the  constant  incursions  of  the 
Danes.  All  that  had  been  done 
was  destroyed;  and  little  more 
than  repairs,  and  military  works, 
could  be  undertaken  till  the  peace- 
able reign  of  Edgar,  in  whose  time 
the  abbey  of  Ramsey  was  founded, 
and  the  church  built  by  AUwin, 
then  alderman  of  all  England.  This 
church  was  built  in  six  years,  and 
finished  in  974.  It  was  in  the 
form  of  a  cross,  and  had  pillars, 
arches,  and  two  towers,  one  of 
which  was  supported  by  four  pil- 
lars,  or  piers,  in  the  middle  of  the 
building.  This  appears  to  have 
been  the  first  English  church  that 


NOR 


NORMAN  (ANGLO)  ARCHITECTURE. 


NOR 


had  a  tower  so  situated,  or  that 
was  built  in  the  form  of  the  cross. 
From  these  descriptions  of  the 
Saxon  churchesi  preserved  in  the 
early  chronicles,  it  appears  that 
the  Saxon  style  was,  like  that  of 
every  other  country,  an  imitation 
of  the  Roman.  The  abbey  church 
of  Ramsey,  which  was  one  of  the 
latest,  and  one  of  the  most  cele- 
brated of  the  works  of  the  Saxons, 
liras  completed  in  six  years.  The 
last  Saxon  work  of  importance  was 
the  abbey  church  of  Westminster, 
built  by  Edward  the  Confessor,  and 
finished  and  consecrated  in  1065, 
one  year  before  the  Conquest.  This 
church  is  represented  to  have  been 
of  a  different  character  from  that 
of  any  preceding  structure  in  Eng- 
land;  and  this  difference  undoubt- 
edly consisted  in  an  approximation 
to  the  Norman  method  of  building. 
Edward  the  Confessor  had  been 
brought  up  in  Normandy,  and  was 
almost  reproached  for  his  incessant 
endeavours  to  introduce  Norman 
customs  and  manners. 

The  churches  and  monasteries 
which  arose  after  theConquestwere 
constructed  after  a  new  manner  of 
building.  Prom  all  this  it  appears 
that  there  must  have  been  a  marked 
difference  between  the  Saxon  and 
the  Norman  fabrics.  But,  as  both 
were  an  imitation  of  the  Roman, 
the  difference  must  have  consisted 
in  the  dimensions  and  the  superior 
workmanship  and  magnificence  of 
the  new  structures.  It  must  have 
been  the  same  style  on  a  grander 
scale,  and  executed  in  a  more  sci- 
entific manner. 

At  the  time  of  the  Conquest  the 
Anglo-Saxons  were  in  every  respect 
a  ruder  and  less  civilized  race  than 
the  Normans  had  by  that  time  be- 
come. 

The  earliest  work  of  the  Nor- 
mans which  exists  in  this  country 
was  conducted  by  Gundulph,  who, 
after  rebuilding  his  cathedral  at 
Rochester,  was  employed  by  Wil- 
liam to  superintend  the  construc- 


tion of  the  White  Tower,  in  the 
Tower  of  London,  which  contains 
within  its  walls  perhaps  the  only 
ecclesiastical  renmant  of  the  Con- 
queror's time  at  present  in  ex- 
istence. 

In  the  course  of  the  Conqueror's 
reign,  several  cathedrals,  abbeys, 
and  castles  were  built,  none  of 
which  remain  in  their  original 
state,  A  remnant  of  the  Con- 
queror's time  existed  at  Canter- 
bury till  within  these  few  years, — 
the  northern  tower,  at  the  west 
end  of  the  cathedral.  This  was  a 
part  of  the  work  of  Lanfranc.  The 
stones  of  which  it  was  built  were 
irregular,  and  the  joints  between 
the  courses  were  wide. 

Several  castles  have  the  reputa- 
tion of  being  of  the  Conqueror's 
time,  but,  on  a  close  investigation, 
wiU  be  found  to  have  been  rebuilt 
in  after  years.  Such  is  the  case 
with  the  castles  of  Norwich,  Ro- 
chester, the  keep  at  Conisborough, 
and  many  others. 

Within  less  than  a  century  after 
the  Conquest  almost  all  the  ca- 
thedrals and  abbey  churches  of 
England,  besides  innumerable  par- 
ish churches,  were  either  wholly 
rebuilt  or  greatly  improved  by  the 
Normans,  on  whom  William  and 
his  successors  conferred  all  the  best 
ecclesiastical  preferments.  By  the 
introduction  of  these  Norman  pre- 
lates, the  Noiman  style  was  rapidly 
diffiised,  at  first,  however,  so  much 
affected  by  the  state  of  art  in  this 
country,  as  to  give  to  the  English 
building  the  character  of  a  Norman 
building  of  much  greater  antiquity. 

Rufus  was  a  great  builder;  bis 
principal  work  was  the  great  hall 
of  his  palace  at  Westminster.  This 
hall,  as  it  now  exists,  was  altered 
by  Richard  II.,  but  much  of  the 
original  work  was  left,  and  during 
the  late  repairs,  portions  of  this 
were  visible.  The  lower  part  of 
the  walls  vnis  faced  with  rubble; 
the  courses  were  irregular;  the 
joints  wide.     Remains  of  a  tri- 


309 


o5 


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NORMAN  (ANGLO)  ARCHITECTURE. 


NOR 


forium  or  gallery  were  discovered, 
which  had  been  carried  along  the 
sides  of  the  hall,  half-way  up.  The 
capitals  of  the  pillars  on  which  the 
round  arches  of  this  gallery  rested 
were  plain  cubes.  The  whole  of 
the  workmanship  was  ooane. 

The  plan  of  the  churches  erected 
about  this  time  was  the  same  as  in 
Normandy.  All  were  built  with 
the  semicircular  chancel,  which  in 
England  afterwards  fell  into  such 
general  disuse  that  few  traces  of  its 
existence  are  to  be  found  in  this 
country.  It  is,  however,  to  be 
traced  in  that  of  St.  Bartholomew. 
le-Grand,  in  London,  (begun  in 
1123,)  in  the  minster  at  York, 
at  East  Ham,  Essex,  and  in  other 
places. 

The  arches  of  the  nave  usually 
rested  on  those  heavy  cylindricid 
iners  which  in  French  churches 
are  ever  hardly  to  be  found,  except 
in  crypts.  Their  prevalence  in 
England  must  be  ascribed  to  the 
inexpertness  of  the  native  woA- 
men,  and  the  probability  is,  that 
they  had  previously  been  adopted 
by  the  Saxons  from  their  inability 
to  imitate  the  Roman  style  in  a 
more  satisfactory  manner.  Some- 
times, to  adorn  the  cylindrical  piers, 
the  Anglo-Normans  introduced  the 
spiral  groove  winding  round  them, 
with  the  net  or  lozenge -work 
spreading  over  them. 

The  windows  and  the  doors 
'were  the  same  as  in  Normandy, 
and  the  Norman  mouldings  were 
gradually  introduced  with  little 
alteration. 

The  walls  are  remarkably  thick, 
and  without  prominent  buttresses. 

Specimens  of  the  time  of  Rufus 
are  to  be  seen  in  the  choir,  side 
aisles,  and  middle  transept  at  Dur- 
ham; in  the  walls  of  the  lower 
part  of  the  western  fa9ade  of  Lin- 
coln; the  towers  and  transept  of 
St.  Alban's;  the  oldest  remaining 
parts  of  Winchester ;  ahd  the  east 
end  and  cross  aisle  of  Worcester. 

The  walls  in  this  reign  were 

310 


irregularly  built,  and  the  joints 
continued  to  be  wide,  as  may  "be 
seen  at  Durham,  Lincoln,  Winches- 
and,  other  places. 

The  style  prevailed  in  the  early 
part  of  the  reign  of  Henry  I.,  as 
may  be  seen  by  the  ruins  of  St. 
Botolph's  priory,  Colchester,  which 
was  built  by  Emulph,  a  Norman 
monk,  in  the  first  years  of  that 
prince.  Here  are  the  same  heavy 
cylindrical  piers,  the  same  stumpy 
proportions,  the  same  poverty  of 
mouldings.  But  in  the  course  of 
this  reign  an  impulse  was  given  to 
architecture  by  one  of  those  men 
of  genius  who  affect  the  character 
of  the  age  in  which  they  live. 
Roger  Poor,  Bishop  of  Salisbury,  a 
Norman  by  birth,  and  combining 
in  himself  the  offices  and  the  qua- 
lities wMch,  in  those  times  of 
constant  commotion,  were  often 
united,  was  much  distinguished  as 
a  prelate,  a  warrior,  a  statesman, 
and  an  architect.  William  of 
Malmsbury  relates,  that  the  vealls 
which  were  built  under  the  super- 
intendence of  Roger  of  Salisbury 
were  so  smooth,  and  had  such  fine 
joints,  that  they  seemed  to  be  made 
of  a  single  stone.  Had  fine  joints 
been  in  use  before,  their  appearance 
in  the  vrorics  of  this  prelate  would 
not  have  been  so  much  extolled. 
The  admiration  vrith  which  they 
are  mentioned  gives  us  the  date  of 
the  first  introduction  of  fine  joints 
in  the  walls  of  English  buildings. 
From  this  time  progressive  im- 
provement took  place  in  other 
parts  of  the  fabric.  Something 
like  decoration  was  added.  The 
portals  began  to  be  enriched.  The 
architecture  of  England  ascended 
to  the  level  of  the  architecture  of 
Normandy  in  the  time  of  William 
the  Conqueror. 

Examples  of  the  style  of  this 
reign  may  be  seen  in  the  naves  at 
Gloucester,  Norwich,  Ely,  Durham, 
and  Southwell ;  also  in  the  lateral 
towers  of  Exeter  cathedral,  built 
by  Bishop  Warlewast ;  in  St.  James's 


NOR 


NORMAN  (ANGLO)  ARCHITECTURE. 


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tower.  Bury  St.  Edmund's ;  in  the 
ruins  of  the  chapter-house  at  Ro- 
chester, built  between  1114  and 
1125,  by  the  same  Emulph  who 
built  St.  Botolph's  at  Colchester, 
and  who,  on  the  death  of  Gundulph, 
was  promoted  to  the  see  of  Roches- 
ter; in  the  p(»tal  of  the  round 
church  at  Cambridge ;  in  the 
nave  of  the  church  at  Dunstable ; 
in  Saint  Bartholomew-le-6rand, 
London,  which  was  begun  in  1 123 ; 
in  St.  Sepulchre's,  Northampton, 
built  by  Simon  de  Liz,  second  earl 
ef  Northampton,  on  his  return 
from  the  Holy  Luid,  and  who  died 
in  1127 ;  and  in  the  abbey  church 
of  Tewkesbury,  begun  by  Robert 
Fitz-Hamon,  (who  died  in  1 107,) 
and  consecrated  in  1123. 

Examples. — ^Portal  of  the  chap- 
ter-house  at  Durham,  built  by 
Bishop  Galfnd  Rufos,  between  1 133 
and  1143 ;  church  of  Castle  Acre 
priory,  Norfolk,  consecrated  in 
1148;  church  of  St.  Cross,  Hamp- 
ahire;  Ripon  minster;  St.frides- 
wide,  (now  Christdiurch,)  Oxford, 
begun  not  later  than  1150,  and 
finished  in  1180. 

About  this  time,  or  a  Uttle  later, 
Domestic  architecture  began  to 
make  its  appearance  in  England, 
though,  fim  the  dimensions  and 
arrangement  d  some  of  those  build- 
ings whidi  have  come  down  to 
oar  time,  it  is  difficult  to  detenmne 
whether  all  of  them  were  destined 
ior  dwelling-houses,  or  were  only 
halls  for  public  occasions,  or  for 
the  courts  of  the  feudal  lords. 

Of  these  buildings  the  invariable 
plan  is  a  parall^gram  of  two 
stories;  sometimes  a  double  pa- 
rallelogram. The  lower  story  was 
vaalted,  as  we  have  seen  to  have 
been  the  custom  in  Normandy,  and 
it  had  no  internal  communication 
with  the  upper  story.  The  upper 
story  was  apiMt>ached  by  an  exter- 
nal stauncase,  wluch  probably  was 
moveable.  The  only  fixed  Norman 
staircase  now  extant  is  the  one  at 
Canterbury. 


The  probability  is  that  the  lower 
story  was  occupied  by  the  servants, 
and  the  upper  story  by  the  masters ; 
but  in  none  of  the  buildings  (tf  this 
time  now  extant  do  there  exist  any 
traces  of  subdivisions. 

An  example  of  Norman  Domestic 
architecture  existed  in  Southwark 
till  within  these  few  yean.  It  was 
the  hostelry  or  town  residence  of 
the  priors  of  Lewes.  The  church  of 
St.  Olave,  Southwark,  was  confirm- 
ed to  the  prior  and  convent  of 
Lewes  by  William,  second  Earl 
Warren  and  Surrey,  the  son  of  the 
founder.  Eari  William  died  in 
1138.  It  appears,  however,  that 
the  priors  of  Lewes  rented  a  build- 
ing  in  1170  and  1186,  for  their  oc- 
cupation in  London ;  from  whence 
it  may  be  concluded,  that  the  hos- 
telry in  question  was  not  built  till 
after  that  period.  The  general 
features  of  the  portion  of  the  hos- 
telry which  remained  till  lately 
nearly  resembled  those  of  the 
manor-house  of  Boothby  Pagnel, 
Moyse'sHall,  at  Bury  St.  Edmund's, 
and  the  building  which  is  called  the 
PytfcAgoras  School  at  Cambridge. 

In  1^26  was  stiU  existing  at 
Bameck,  in  Northamptonshu^,  a 
Norman  manor-house,  which  was 
not  built  for  defence.  In  this  in- 
stance the  hall,  which  was  the 
principal  feature,  was  on  the  ground 
floor,  and  had  no  vaults  underneath. 
The  hall  consisted  of  a  centre  and 
two  side  aisles.  The  fine  joints  of 
the  walls  of  this  building  denoted 
that  it  could  not  have  been  built 
much  before  the  middle  of  the 
twelfth  century. 

At  Bury  St.  Edmund's  is  a  Nor- 
man domestic  building,  which  goes 
by  the  name  of  Moyse's  Hall. 

At  Boothby  Pagnel,  in  Lincoln- 
shire, is  a  Norman  manor-house  on 
nearly  the  same  plan.  In  this  are 
a  fire-place  and  a  chimney,  which 
indicates  that  the  building  oif  which 
it  forms  a  part  cannot  be  older  than 
the  second  half  of  the  twelfth  cen- 
tury.   This  edifice  has  windows  in  | 


311 


NOR 


NORMAN  (ANGLO)  ARCHITECTURE. 


NOR 


fm0m 


the  ends  as  well  as  the  sides,— a 
circuiDStance  whieh  makes  it  evi- 
dent that  to  this  building  no  others 
could  have  been  attached.  It  is 
surrounded  by  a  moat. 

At  Christchuich,  Hants,  is  a  Nor- 
man remnant  which  has  also  a 
chimney. 

At  Lincoln  is  a  Norman  domestic 
building  which  goes  by  the  name 
of  *  John  of  Gaunt's  Stables/  but 
which,  in  fact,  was  the  public  meet- 
ing-house of  a  guild.  It  is  so  much 
enriched  as  to  be  placed  late  in  the 
reign  of  Henry  II. 

These  examples  prove  that  about 
the  middle  of  the  twelfth  century, 
mansions,  distinct  from  castles  for 
defence,  began  to  be  erected  in 
England;  and  that,  independent  of 
colleges,  abbots'  lodgings,  and  the 
habitable  parts  of  convents,  in- 
stances  existed  of  Domestic  archi- 
tecture. But  it  was  long  before 
dwelling-houses  acquired  a  charac- 
ter bearing  any  relation  to  the  qua- 
lity of  the  proprietor,  or  were  con- 
structed with  much  regard  to  con- 
venience. 

Examples  of  the  Norman  style 
of  the  time  of  Henry  II.  are  to  be 
seen  in  the  abbey  gateway,  Bristol; 
in  the  Galilee,  or  chapel,  at  the 
west  end  of  Durham,built  by  Bishop 
Pudsey  (1154  to  1197),  together 
vdth  the  lateral  portak  of  the 
nave ;  in  the  new  nave  and  great 
west  portal  of  Rochester,  &c. 

It  was  in  the  latter  years  of  the 
reign  of  Henry  II.  that  the  struggle 
between  the  Biound  and  the  Pointed 
styles,  which  is  called  the  Transi- 
tion, beg^n  to  take  place  in  this 
country. 

Kirkstal  abbey,  in  Yorkshire,  was 
built  in  the  thirty  years  preceding 
1183.  The  nave  ardies  are  pointed, 
but  the  pillars  are  massive,  and  the 
Y^indows  and  portals  are  round. 
The  church  at  Roche  abbey,  though 
equally  in  the  Transition  style,  and 
having  round  -  headed  windows 
above  pointed  archesy  Norman 
mouldings  and  capitals,  yet  is  of  a 

312  "^ 


less  heavy  character.  Both  build- 
ings, however,  denote  that  daring 
those  years  the  new  style  was  only 
just  beginning  to  be  received  in 
England. 

About  the  same  time  (1170), 
Archbishop  Roger  employed  the 
Pointed  style  in  the  new  crypt  of 
York  minster. 

But  the  early  examples  of  the 
Transition,  of  which  the  dates  are 
known  with  the  most  undoubted 
certainty,  aro  the  round  x^^^  of 
the  Temple  church,  London,  which 
was  consecrated  in  1185,  and  the 
choir  of  Canterbury  cathedral, 
which  was  rebuilt  after  the  fire  in 
1175,  and  in  which  the  Pointed 
style  was  introduced  by  John  of 
Sens,  a  French  architect.  Other 
instances  are  to  be  found  in  the 
great  tower  at  the  west  end  of  Ely, 
built  by  Bishop  Ridel,  who  died  in 
1189;  in  the  county  hall  of  Oke- 
ham,  Rutlandshire;  in  the  abbey 
church  of  Glastonbury,  &c. 

But  the  nave  of  Rochester  and 
the  nave  of  Peterborough,  rebuilt 
between  1170  and  1194,  are  proofs 
that  the  old  fashion  was  not  at  once 
superseded  by  the  new. 

Simultaneously  with  the  intro- 
duction of  the  Transition  style, 
hewn  stone  vaults  appear  to  have 
been  first  thrown  over  the  wider 
parts  of  English  churches,  which 
till  then  had  been  habitually  roofed 
with  wood.  A  stone  vault  was 
thrown  over  the  new  choir  of  Can- 
terbury, in  1 1 74.  It  was  customary 
before  that  time,  to  roof  narrow 
spaces  with  plain  cross-vaulting, 
but  not  to  vault  wide  spaces  with 
stone.  Plain  cross-vaulting  of  rub- 
ble, with  and  without  ribs,  had 
been  adopted  before  in  crypts,  side 
aisles,  and  chancels.  Barrel-vault- 
ing, we  have  seen,  was  introduced 
in  the  time  of  WiUiam  the  Con- 
queror. From  the  time  that  the 
choir  of  Canterbury  was  built,  which 
was  not  long  after,  it  became  com- 
mon to  throw  stone  vaults  over  the 
naves  of  the  larger  churches  of 


NOR 


NOZZLES. 


NOZ 


Normandy,  and  hewn  stone  vaults, 
plain  at  first,  and  gradually  en- 
riched, became  habitual  in  Eng- 
land* Prominent  buttresses  and 
flying  buttresses,  as  in  Normandy, 
followed  in  the  train  of  the  stone 
roofs. 

From  this  time,  the  Round  style 
fell  gradually  into  disuse;  but  at 
Fountain's  abbey,  the  foundations 
of  which  were  laid  in  1204,  and 
which  was  in  progress  during  the 
forty  subsequent  years,  the  win- 
dows and  portals  are  still  round- 
headed;  and  an  instance  of  a  round 
portal  is  to  be  found  at  Ketton,  in 
Rutlandshire,  so  late  as  1252. 

During  the  reign  of  Heniy  III. 
the  Early  Pointed  style  attained  its 
most  perfect  condition.  Fine  ex- 
amples of  this  style  are  to  be  seen 
in  the  chapter-house,  the  transepts, 
and  part  of  the  choir  of  Westmin- 
ster abbey ;  in  the  choir  of  St.  Al- 
ban's;  in  the  nave  of  Lincoln; 
east  end  of  Durham ;  nave  of  Wor- 
cester, 1224;  nave  and  spire  of 
Lichfield;  south  transept  of  York; 
and  the  older  part  of  the  choir  of 
Southwell;  and  in  Salisbury  ca- 
thedral, which  was  begun  in  1221, 
and  carried  forward,  without  inter- 
ruption, till  it  was  completed. 

The  establishment  of  the  Pointed 
style  was  attended  with  one  re- 
markable difference  in  England 
and  Normandy.  In  Normandy,  the 
semicircular  chancel  became,  ge- 
nerally speaking,  polygonal;  in 
England,  generally  spelling,  it  be- 
came square.  Polygonal  chancels 
are  as  rare  in  England  as  square 
chancels  are  in  the  larger  churches 
of  Normandy ;  and  this  difference 
of  shape  in  England  afforded  the 
opportunity  of  those  magnificent 
east  windows,  which  are  so  princi- 
pal and  so  splendid  a  feature  of  our 
cathedrals.  Another  difference  to 
be  remarked,  is  the  battlement, 
which  usually  forms  the  parapet  of 
English  churches,  and  which  never 
occurs  in  the  ecclesiastical  build- 
ings of  France. 

313  ^ 


It  may  be  said, — 1.  That  the 
supposed  existence  of  the  Pointed 
style  in  Normandy,  in  1056,  is 
imaginary.  2.  That  the  Normans, 
adopting  the  corrupt  Roman  style, 
gave  it  a  character  of  their  own. 
3.  That  the  Normans  greatly  con- 
tributed to  the  advancement  of  the 
arts  in  England.  4.  That  archi- 
tecture performed  exactly  the  same 
revolution  in  England  and  France, 
France  having,  in  all  the  changes, 
a  certain  precedence. 

Norroyt  or  North  ray,  in  heraldry, 
one  of  the  two  provincial  Kings  at 
Arms,  whose  jurisdiction  lies  on  the 
north  side  of  the  Trent,  as  does 
that  of  Clarendeux  to  the  south 

Northampton  Tables,  Tables  made  at 
the  county  town  of  Northampton, 
formed  from  the  registers  of  burials 
of  that  locality,  from  which  calcu- 
lations were  made  of  the  value  of 
life,  for  the  purpose  of  its  insurance. 
(See  article  Assurance,) 

Nosing,  the  prominent  edge  of  a 
moulding  or  drip ;  the  projecting 
moulding  on  the  edge  of  a  step 

Nosing  of  steps,  the  projecting  parts 
of  the  treaid-board  or  cover,  which 
stand  before  the  riser.  The  nosing 
of  steps  is  generally  rounded,  so  as 
to  have  a  semicircular  section;  and 
in  good  staircases  a  hollow  is  placed 
under  them. 

Notch 'board,  a  board  notched  or 
grooved  out,  to  receive  and  sup- 
port the  ends  of  the  steps  of  a  stair- 
case   * 

Notching,  the  cutting  of  an  excava- 
tion throughout  the  whole  breadth 
of  a  substance :  by  this  means  tim- 
bers are  fastened  together,  or  their 
surfaces,  when  joined  at  angles,  are 
made  to  coincide 

Nozzles,  those  portions  of  a  steam  en- 
gine in  which  are  placed  the  valves 
that  open  and  close  the  communi- 
cation between  the  cylinder  and 
the  boiler  and  condenser,  in  low- 
pressure  or  condensing  engines; 
and  between  the  cylinder  and  boiler 
and  atmosphere,  in  high-pressure 
or  non-condensing  engines 


NTJC 


OAK. 


OBE 


Nucleus,  the  internal  part  of  the  floor- 
ing of  the  ancients,  consisting  of  a 
strong  cement,  over  which  was  laid 
the  payement,  which  was  bound 
with  mortar 

iVtosonce,  any  thing  tending  to  hurt, 
to  annoy,  or  to  endanger  health. 
(See  the  excellent  w(»rk  by  Mr. 
Gibbons  on  this  subject.) 

NuUah,  in  India,  a  natural  canal,  or 
smaU  branch  of  a  riyer 

Nunnery f  a  Roman  Catholic  building 
for  an  association  of  nuns  or  females 
devoted  to  a  life  of  religious  seclu- 
sion. Previous  to  the  Reformation, 
there  existed  in  England  127  edi- 
fices for  the  conyenient  lodging  of 
such  pious  women,  2  in  Wales,  and 
20  in  Scotland;  in  the  whole  in 
Great  Britain,  149.  But  there 
were  many  convents  and  religious 


OAK 

Oak.  There  are  two  kinds  of  this 
timber  common  in  England,  on  the 
Continent,  and  in  America.  Oak  of 
good  quality  is  more  durable  than 
any  other  wood  which  attains  the 
same  size:  its  colour  is  a  well- 
known  brown.  Oak  is  a  most  va- 
luable wood  for  ship-building,  car- 
pentry, frames,  and  works  requiring 
great  strength  or  exposed  to  the 
weather.  It  is  also  much  used  for 
carved  ornaments,  panelling  of 
rooms,  pulpits,  stalls,  and  stand- 
ards for  churches.  It  is  likewise 
used  in  the  construction  of  all  kinds 
of  buildings,  for  strength  and  sta- 
bility. English  oak  is  one  of  the 
hardest  of  the  species :  it  is  consi- 
derably harder  than  the  American, 
called  white  and  red  Canada  oak. 
African  oak  is  well  adapted  to  the 
construction  of  merchant  vessels. 
Italian  oak  is  much  purchased  for 
our  dockyards,  to  the  prejudice  of 
that  which  is  proudly  standing  in 
our  several  forests. 

Obetisk,  in  architecture,  a  quadran- 
gular pyramid  :  those  of  Egypt  may 
be  described  as  large  stones,  qua* 
drilateral,    cUminishing  from    the 

314 


houses  not  specially  named  nun- 
neries, but  which  were  receptacles 
also  for  such  purposes. 

Nmmery,  a  term  sometimes  applied 
to  the  triforium  or  gallery  b^een 
the  aisles  of  a  church  and  the  clere- 
story ;  so  called  from  the  situation 
of  the  nuns'  choir  in  some  convents. 
At  the  present  time,  the  roomy 
galleries  over  the  aisles  in  West- 
minster abbey  are  called  nunneries, 
probably  from  having  been  used  by 
the  nuns  of  Kilbume,  when  they 
visited  the  abbey,  to  which  they 
were  subordinate. 

Nut,  a  short  internal  screw,  whicb 
acts  in  the  thread  of  an  external 
screw,  and  is  employed  to  fasten 
any  thing  that  may  come  between 
it  and  a  flange  on  the  bottom  of 
the  external  screw  or  bolt 


OBE 

base  upwards,  till,  within  about  a 
tenth  oif  the  height,  the  sides  con- 
verge to  a  point.    The  width  of 
the  base  is  usually  about  a  tenth  of 
the  height,  to  that  part  where  the 
sides  begin  to  converge :  they  are 
commonly  formed  from  a  single 
stone,  mostly  of  granite.    There 
are,  however,  two  small  obelisks 
in  the  British  Museum,  formed  oi 
basalt,  and  one  at  Philae,  of  sand- 
stone.   When  obelisks  were  first 
made  in  Egypt,  it  was  customary 
with  the  patriarchs  of  the  Jews  to 
set  up  stones  to  perpetuate  the 
memory  of  great  events.    Strsbo 
calls  such  stones  *books  of  history; 
an  epithet  which  might  be  applied 
with  propriety  to   the    inscribed 
Egyptian  obelisks.     The  date  of 
the  Plaminian  obelisk,  which  is 
covered  with  hieroglyphics,  is  by 
some  writers  supposed  to  be  be- 
tween 1580  and  1600  b.c.  The  first 
obelisk  vras  raised    by  Barneses, 
King  of  Egypt,  in  the  time  of  the 
Trojan  vnur :  it  was  40  cubits  high, 
and  employed  20,000  men  in  build- 
ing.   Phins,  another  king  of  Egypt* 
raised  one  of  45  cubits,  and  Ptolemy 


OBL 


ODONtOGRAPH. 


ODO 


Philadelphus  another  of  88  cubits, 
in  memory  of  Arsinoe,  &c.  The 
Romans  also  erected  many,  which 
are  well  described  in  Roman  history. 

Oblate,  flattened  or  shortened;  in 
geometry,  a  term  applied  to  a  sphe- 
roid, produced  by  the  revolation  of 
a  semi-ellipsis  about  its  shorter 
diameter.  Of  this  figure  is  the 
earth,  and  probably  all  the  planets, 
having  the  equatorial  diameter 
greater  than  the  polar. 

ObUquCj  in  geometry,  aslant ;  not  di- 
rect ;  not  perpendicular  nor  parallel 

Oblique  angUj  one  that  is  greater  or 
less  than  a  right  angle 

ObUque-angled  triangle,  one  that  has 
no  right  angle 

ObUque  arches,  or  Oblique  bridges,  are 
those  which  conduct  high  roads  or 
railroads  across  a  river,  canal,  &c., 
in  an  oblique  direction:  they  are 
also  called  'skew  arches 

ObUque  line.  When  one  straight  line 
stt^nds  upon  another,  and  makes 
unequal  angles  therewith,  the  an- 
gles are  said  to  be  oMique,  the  one 
bdng  greater  than  a  right  angle, 
and  the  other  less :  hence  a  Mne  is 
only  oblique  as  it  relates  to  another 
line ;  otherwise  the  word  would  be 
destitute  of  meaning. 

Oblique  sailing  occurs  when  a  ship, 
bdng  in  some  intermediate  rhumb 
between  the  four  cardinal  points, 
makes  an  oblique  ang^e  with  the 
meridian,  and  continually  dianges 
both  its  latitude  and  lon^ude 

Oblong,  a  rectangle  of  unequal  dimen- 
sions; in  geometiy,  longer  than 
broad 

ObservtUpry,  a  building  erected  for 
the  purpose  of  making  observations 
on  the  motions  of  the  heavenly 
bodies.  More  particularly  with  re- 
fierence  to  the  study  of  Terrestrial 
Magnetism,  observatories  have  been 
erected  by  the  British  Government 
in  Canada,  St.  Helena,  the  Cape  of 
Good  Hope,  and  Van  Dieman's 
Island;  by  the  East  India  Com- 
pany at  Madras,  Singapore,  Simla, 
and  Trevandrum ;  and  by  the  Rus- 
sian Government  at  St.Peter8burgh 

315 


and  other  places,  in  connection  with 
those  at  Gottingen,  &c.  The  most 
munificent  example  of  private  de- 
votion to  the  science  of  Astronomy 
is  the  splendid  observatory  erected 
by  Lord  Rosse  at  Pensantown,  in 
Ireland. 

Obtunding,  the  blunting  or  taking 
away  a  sharp  comer 

Obtuse,  in  geometry,  blunt ;  in  oppo- 
sition to  acute  or  sharp 

Obtuse  angle.  In  geometry,  if  the 
contained  angle  be  less  than  a  right 
angle,  it  is  called  an  acute ;  if  greater, 
it  is  called  an  obtuse  angle. 

{^tuse -angled  triangle,  a  triangle 
which  has  an  obtuse  angle 

Obtuse  section  of  a  cone,  the  hyper- 
bola of  andent'  geometricians,  be- 
cause they  considered  it  only  such 
a  cone  whose  section  through  the 
axis  was  an  obtuse-angled  triangle 

Occus,  the  banqueting  -  room  of  a 
Roman  house.  There  were  several 
kinds  of  occi,  viz.  Corinthian,  tetra- 
style,  Cyzicene,  and  Egyptian.  In 
the  Greek  houses  the  occi  were 
spacious  apartments,  in  which  the 
mistress  of  the  family  employed 
herself  and  servants  at  the  loom 

Ochre,  brown,  a  clay  coloured  brown 
by  the  oxide  of  iron 

Ochre,  red,  a  day  coloured  red  by 
the  oxide  of  iron 

Ochre,  yellow,  a  clay  coloured  ydlow 
by  the  oxide  of  iron 

Octagon,  a  figure  of  eight  sides  and 
as  many  angles :  when  all  the  sides 
and  all  the  angles  are  equal,  the 
figure  is  called  a  regular  octi^n 

Octahedron,  in  geometry,  one  of  the 
five  regular  bodies,  consisting  of 
eight  equal  and  equilateral  triangles 

Oetostylos,  a  portico  which  has  eight 
columns  in  front 

Odeum,  a  small  theatre  for  the  reci- 
tation of  musical  compositions, 
generally  in  the  ndghbourfaood  of 
the  theatre :  the  odeum  at  Athens 
was  contiguous  to  the  theatre  of 
Bacchus;  the  odeum  at  Pompeii 
also  joined  the  theatre 

Odontograph,  a  very  ingenious  instru- 
ment, invented  by  I^fessor  Willis, 


(EC 


ORATORY. 


ORA 


of  Cambridge,  to  enable  the  mill- 
wright, workman,  and  engineer  to 
measure,  draw,  and  design  infinitely 
in  extent,  the  teeth  of  wheels 

(Eeu$t  according  to  YitruTius,  apart, 
ments  near  or  connected  with  the 
dining-room 

Offieest  as  connected  with  the  domes- 
tic purposes  of  large  mansions, 
palaces,  &c.,  consist  of  kitchens, 
sculleries,  pantries,  breweries,wash. 
houses,  &c. ;  frequently  detached 
or  out-houses,  and  sometimes,  in 
cities,  underground  and  vaulted 
places  beneath  the  same  roof 

OficeSf  as  connected  with  business, 
are  apartments  for  the  accommo- 
dation of  clerks  or  accountants; 
merchants'  counting-houses,  &c.; 
for  law  clerks,  law  agents,  &c. 

Qffinfft  in  navigation,  that  part  of  the 
sea  distanced  from  the  shore  where 
there  is'  deep  water,  and  no  neces* 
sity  for  a  pilot 

Offget,  or  Set-off t  the  splay  or  narrow 
slanting  course  of  stone  or  brick, 
serving  to  connect  two  portions  of 
a  wall,  the  uppermost  of  which  re- 
cedes from  the  face  of  that  beneath 

Ogee,  a  moulding  consisting  of  two 
members,  the  one  concave,  the 
other  convex ;  the  same  with  what 
is  otherwise  called  cymatium.  In 
Gothic  architecture,  ogees  are  very 
much  employed.  The  term  ogee  is 
also  applied  to  a  pointed  arch,  the 
sides  of  which  are  each  formed  of 
two  contrasted  curves. 

Ogives,  arches  or  branches  of  a  Gothic 
vault,  which,  instead  of  being  cir- 
cular, pass  diagonally  from  one 
angle  to  another,  and  form  a  cross 
with  the  other  arches  which  make 
the  side  of  the  squares,  whereof 
the  ogives  are  diagonals.  The 
middle,  when  the  ogives  cut  or 
cross  each  other,  is  called  the  key, 
sometimes  carved  in  the  form  of  a 
rose.  The  members  or  mouldings 
of  the  ogives  are  called  nerves, 
branches,  or  veins ;  and  the  arches 
which  separate  the  ogives,  double 
arches. 

Oillets,  or  Oglets,  small  opemngs  or 

316 


loopholes,  sometimes  circular ;  ex- 
tensively used  in  the  fortifications 
of  the  middle  ages 

0/te«r,  a  small  l&hammer,  worked 
by  the  foot.  The  hammer  head  is 
about  2^  inches  square  and  10 
inches  long,  with  a  swage  tool 
having  a  conical  crease  attached  to 
it,  and  a  corresponding  swage  is 
fixed  in  a  square  cast-iron  anvU- 
block,  about  12  inches  square  and 
6  deep,  with  one  or  two  round 
holes  for  punching,  &c.  The  ham- 
mer handle  is  about  2  to  2^  feet 
long,  and  mounted  in  a  cross- 
spindle  nearly  as  long,  supported 
in  a  wooden  frame  between  end- 
screws,  to  adjust  the  groove  in  the 
hammer  face  to  that  in  the  anvil- 
block.  A  short  arm,  5  or  6  inches 
long,  is  attached  to  the  right  end 
of  the  hammer  axis;  and  from  this 
arm  proceeds  a  rod  to  a  spring- 
pole  overhead,  and  also  a  chain  to 
a  treadle  a  little  above  the  floor  of 
the  smithy. 

Olympiad,  a  period  of  four  years,  by 
which  the  Greeks  reckoned  their 
time.  The  first  Olympiad  corre- 
sponds with  the  775th  year  before 
the  birth  of  our  Saviour,  and  22 
years  before  the  building  of  Rome. 

OoUte,  the  Portland  stone  used  in  ar- 
chitecture, called  also  freestone 
and  roestone 

Opa,  according  to  Yitruvius,  a  bed  or 
cavity  in  which  the  head  of  a  tie- 
beam  rests 

Opaqwe,  cloudy,  not  transparent 

^hitet,  a  black  marble 

Opisthodomoe,  the  enclosed  space  be- 
hind a  temple:  the  treasury  at 
Athens  was  so  called,  because  it 
stood  behind  the  temple  of  Minerva 

Oppidum,  according  to  the  Romans, 
a  mass  of  buildiQgs;  an  entrance 
to  a  town;  the  fri^ade  to  a  public 
building ;  not  unlike  to  the  termini 
on  the  principal  lines  of  railway 

Opposite  angleSf  those  which  are 
formed  by  two  straight  lines  cross- 
ing each  other,  but  not  two  adja- 
cent angles 

Opposite  cones  are  those  to  which  a 


ORA 


ORDNANCE  SURVEY. 


ORD 


straight  line  can  be  every  where  ap- 
plied on  the  surface  of  both  cones 

Opposite  sectiofUf  those  made  by  a 
plane  cutting  two  opposite  cones 

Opticgf  the  science  of  direct  vision, 
including  catoptrics,  dioptrics,  and 
perspective. 

Optostrotum,  according  to  the  Greek, 
a  brick-paved  flooring 

Opwt,  Roman  reticulated  masonry;  a 
mode  of  workmanship 

Or,  in  heraldry,  gold  :  it  is  denoted 
in  engraving  by  small  points  all 
over  the  field  or  bearing 

Ora^  a  Roman  hawser 

Oratory^  a  small  private  chapel  or 
closet  for  devotion 

Orb,^  mediaeval  term  for  a  blind 
window 

Orbsj  in  Gothic  ornament,  bosses  and 
knots  of  foliage,  flowers,  or  other 
ornament  in  cornices 

OrbicukUf  according  to  Vitruvius,  a 
roller  or  a  pulley  revolving  upon 
an  axis,  and  having  a  groove  in  its 
circumference  for  the  rope  to  .fit 
into;  employed  as  a  mechanical 
power  for  raising  or  drawing 

Orchestra,  the  area  in  the  Greek 
theatre  comprised  between  the 
lower  range  of  seats  and  the  pro- 
scenium.  In  the  Roman  theatre, 
the  orchestra  was  appropriated  to 
the  senators;  but  in  the  theatres 
of  the  Greeks  it  was  the  scene  of 
action  of  the  dancers. 

Orders  of  Architecture^  usually  named 
the  'five  orders,'  without  reference 
to  other  styles  of  architecture,  are 
thus  enumerated  by  most  writers : 
L  Tuscan.  2.  Doric.  3.  Ionic. 
4.  Corinthian.  5.  Composite.  (For 
their  proportions,  see  Architec- 
ture,) 

OrdinateSf  in  geometry  and  conies, 
lines  drawn  horn  any  point  of  the 
circumference  of  an  ellipse,  or 
other  conic  section,  perpendicularly 
across  the  axis,  to  the  other  side 

Ordnance  Survey  of  Great  Britain  and 
Ireland :  a  work  of  great  import- 
ance in  ascertaining  the  true  geo- 
graphical position  of  our  islands 
and  of  their  varied  superficial  fea- 

317  ~" 


tures.  This  survey  originated  in 
the  mutual  desire  on  the  part  of 
English  and  French  philosophers 
to  determine  the  precise  diiference 
of  longitude  between  the  meridi- 
ans of  the  Greenwich  and  Paris 
observatories.  In  the  pursuit  of 
this  object,  a  meeting  was  arranged 
at  Dover  between  three  members 
of  the  French  Academy,  MM.  Cas- 
sini,  Mechain,  and  Legendre,  and 
General  Roy  and  Dr.  Blagden,  to 
arrange  plans  of  operation.  In  the 
course  of  the  subsequent  survey, 
the  Officers  of  the  Royal  Artillery, 
to  whom  the  superintendence  of 
the  work  was  intrusted,  extended 
their  views  and  operations,  and, 
under  the  patronage  and  at  the 
expense  of  the  Board  of  Ordnance, 
proceeded  to  determine  the  length 
of  as  many  degrees  on  the  meridian 
as  came  within  the  limits  of  the 
survey.  The  rules  by  which  the 
main  lines  for  this  and  all  other 
extended  surveys  are  obtained, 
are  derived  from  the  principles  of 
trigonometry,  or  the  properties  of 
triangles.  By  these  principles  we 
are  enabled  to  compute  the  exact 
form  and  dimensions  of  any  triangle 
from  the  actual  measurement  of 
one  side  only,  and  of  the  angles 
formed^  at  its  extremities  by  the 
other  sides.  Upon  these  principles 
the  true  figure  and  size  of  our 
globe  have  been  determined  upon 
the  relative  lengths  of  degrees  of 
a  meridian  in  different  latitudes. 

The  exactness  of  the  results  of 
these  operations  depending  upon 
the  correct  measurement  of  the 
one  side,  or  base  Unci  and  of  the 
angles  at  its  ends,  formed  by  the 
two  imaginary  sides  which  have 
a  common  meeting  point  in  some 
distant  and  conspicuous  object,  the 
apparatus  for  measuring  this  side 
and  the  angle  is  required  to  act 
vrith  extreme  delicacy  and  exact- 
ness. For  measuring  the  length, 
rods  of  various  materials  have  been 
used,  and  endeavours  made  to 
obviate  the  effect  of  changes  of 


OHD 


ORDNANCE  SURVEY. 


ORD 


temperature  in  attering  the  length 
of  the  rods  themselTes.  General  Roy 
commenced  the  measurement  of 
a  base  hne  on  Hounslow  Heath 
with  rods  of  deal,  eadi  twenty 
feet  long.  But  these  rods,  although 
prepared  in  the  most  careful  man- 
ner, of  the  best  seasoned  timber, 
perfectly  straight,  and  effectually 
secured  i^nst  bending,  were 
found  to  suffer  stich  chuiges  of 
length,  from  the  Tsrying  shyness 
and  moisture  of  the  air,  as  ren- 
dered them  utterly  unlit  for  the 
purpose,  and  glass  tubes  were 
CTentually  substituted,  each  of 
them  twenty  feet  long,  and  en- 
closed in  a  frame  of  wood,  allow- 
ing only  expansion  or  contraction 
in  length  from  heat  or  cold  ac- 
cording to  a  law  ascertained  by 
experiments.  With  these  rods  a 
base  of  about  5^  miles  in  length 
was  measured  so  exactly,  that  a 
remeasurement  by  Colonel  Mudge 
several  years  afterwards,  made  with 
a  steel  chain  constructed  by  the 
celebrated  Ramsden,  differed  only 
from  the  original  line  to  the  extent 
of  2f  in.  Steel  chains  are  jointed 
similar  to  a  watch-chain,  and  are 
always  used  with  uniform  tension, 
the  differences  in  length  due  to 
temperature  being  calculated  upon 
the  observed  feet,  that  each  degree 
of  heat  above  62  Fahr.  extends  the 
chain  '0075  of  an  inch. 

For  determining  the  angles,  the 
English  Officers  used  an  excellent 
theodolite  by  Ramsden,  having 
both  an  altitude  and  an  azimuth 
circle,  and  a  telescope  of  great 
power.  This  instrument,  com- 
bining the  powers  of  a  theodolite, 
a  quadrant,  and  a  transit  instru- 
ment, is  capable  of  measuring  hori- 
zontal angles  to  fractions  of  a 
second.  It  is  recorded  among  the 
proofs  of  the  accuracy  attaint  in 
this  triangulation,  that  a  testing 
line,  or  btue  ttf  ver^atwni  as 
termed  in  geodesic  operations, 
measured  on  Salisbury  Plain,  of 
which  the  length  exceeded  seven 

318 


miles,  differed  only  one  inch  from 
the  computation  carried  throogh 
the  series  of  triangles  from  Houns- 
low Heath  to  SaKsbury  Plain. 

When  the  primary  triangulation 
had  been  thus  carefully  completed, 
a  frurther  subdivision  of  each  of 
these  great  tiianglea  vras  i>erform- 
ed,  and  each  of  these  again  vras 
subdivided  into  others,  so  that  the 
entire  plot  of  the  country  was  re- 
presented by  a  comi^ete  net-woik 
of  triangles.  Each  of  these 'divi- 
sions  and  subdivisions  being  form- 
ed independently  of  the  others, 
and  yet  the  exact  accordance  of 
the  whole  being  insisted  on  and 
effected,  accuracy  is  secured  4n  all 
these  principal  operations,  and  the 
filling  in  of  each  of  these  spaces 
is  intrusted  to  a  different  class 
of  operators,  whose  labours  in  pro- 
ducing the  finsl  plan  are  so  divided 
and  arranged  that  the  work  of 
each  is  a  chedc  upon  the  exactness 
of  his  predecessor.  Thus  the  sur- 
veyors  measure  the  lines  and  angles 
on  the  ground,  but  another  class 
of  assistants  (the  plotters)  produce 
the  plan  from  the  records  of  the 
surveyors,  and  a  third  class  (ex- 
aminers) test  the  plan,  thus  pro- 
duced, by  subsequent  oompsrison 
in  the  field.  One  effect  of  this 
system,  by  which  the  range  of  ope- 
rations confided  to  each  operator 
is  thus  limited,  and  the  fidelity  of 
these  thus  severely  scrutinized,  is, 
that  the  bulk  of  the  work  after 
the  triangulation  may  be  safely 
confided  to  an  inferior  and  cheaply 
engaged  dass  of  assistants,  and 
great  comparative  economy  thus 
attained. 

The  Ordnance  Survey  of  Great 
Britain  and  Ireland  is  plotted  to 
diflbrent  scales.  Thus  the  whole 
of  Ireland  is  plotted  on  a  scale  of 
six  inches  to  a  mile,  and  is  con- 
tained on  1907  sheets  of  maps, 
vHiich  may  be  purchased  at  2».  6<f  . 
and  5«.  each.  The  Survey  of  Eng- 
land and  Wales  is  plotted  on  a 
scale  of  one  inch  to  a  mUe,  and 


ORD 


ORGAN. 


ORG 


comprised  in  110  sheets  (of  which 
ninety  are  abready  published),  at 
29.  each ;  about  half  of  these  are 
published  in  quarter-sheets  at  6^. 
eadi.  Portions  of  Lancashire  and 
Wigtonshire  are  plotted  at  six 
inches  to  a  mile,  price  2«.  6J.  and 
5«.  each;  and  the  towns  of  Dublin, 
Wigan^  Blackburn/ Chorley,  and 
liyerpool,  upon  the  large  scale  of 
five  feet  to  a  miley  from  28,  to 
3«.  6d.  each.  It  is  only  the  one-inch 
survey  which  has  the  hills  shaded. 
A  Geological  Survey,  which  besides 
giving  the  one-inch  maps  geolo- 
gically coloured,  shows  horizontal 
and  vertical  sections  of  the  country, 
is  also  in  progress,  and  is  com- 
pleted over  some  of  the  south-west- 
em  counties. 

The  estimate  for  the  recently 
completed  Ordnance  Survey  of 
London  was  as  follows: — "That  a 
block-plan  of  the  metropolis,  and 
of  the  suburban  districts  included 
within  a  radius  of  eight  miles  from 
St.  Paul's,  may  be  executed,  with 
a  proper  system  of  levels,  for 
jS  24,215,  and  that  the  cost  of 
engraving  the  block-plan,  upon  a 
scale  of  five  feet  to  the  mile,  and 
upon  901  plates  of  double  elephant 
size,  would  be  (including  £  3,604 
for  the  copper)  £  12,614.,  making 
together  £  36,829."  The  plan  has 
been  produced  at  a  cost  vrithin  this 
estimate,  and  the  engraving  will 
probably  be  executed  considerably 
below  the  estimate. 
Organ,  This  word  is  derived  from 
the  Greek  organon:  Grganum  in 
Latin,  orgtmo  in  Italian,  orgue  in 
French,  orgel  in  German.  It  signi- 
fies, generally,  an  instrument ;  but 
is  now  used  for  the  name  of  the, 
grandest  and  most  worthy  of  mu- 
sical instruments. 

The  tones  of  an  organ  are  pro- 
duced from  the  pipes  only;  of 
these  some  are  of  wood,  others  of 
yarious  kinds  of  metal,  and  even  of 
glass.  An  organ  of  full  compass 
may  contain  all  the  sounds  recog- 
nized in  the  science  of  music,  from 


the  lowest  appreciable  to  the  very 
highest. ,  The  largest  pipes  pro- 
duce the  lowest  sounds,  and  some 
few  are  liade  as  long  as  about  32 
feet,  vdiile  the  smallest  are  about 
the  size  of  the  pipe  of  a  very  small 
key.  Organs  are  of  various  kinds, 
viz.  for  the  church,  the  concert- 
room,  and  for  the  private  drawing- 
room.  The  church  organ  should 
be  of  a  full,  deep,  and  solemn  cha- 
racter; while  the  concert-room 
organ  should  be  of  a  lighter  and 
more  brilliant  kind,  with  every  va- 
riety  of  stop,  in  order  to  imitate, 
not  only  the  full  orehestre,  but  also 
certain '  solo'  instruments.  Hence 
we  have  the  flute-st^p;  the  haut- 
boy,  the  cremona,  or  krum-hom ; 
the  vox-humana,  &c.  stops;  ac- 
cording to  the  extent  of  the  instru- 
ment. These  solo,  or  faucy  stops, 
belong  only  to  the  concert-room 
or  drawing-room  organ,  an4  are 
wholly  unbecoming  in  one  for  the 
church. 

We  have  not  space  to  give  any 
thing  like  a  description  of  this  the 
noblest  of  instr^ents;  and  it 
must  suffice  to  say  that  it  consists 
of  a  bellows  whibh  supplies  the 
pipes  vrith  wind  by  means  of  a 
wind  chest;  the  wind  being  con- 
veyed therefrom,  through  chi^nels, 
under  the  different  ranks,  or  rows 
of  pipes,  and  thence  into  the  pipes 
by  means  of  pallets,  or  valves, 
opened  at  the  pleasure  of  the  per- 
former, by  pressing  the  proper 
lever  or  key. 

The  organ  is  a  very  ancient  in- 
strument of  the  church,  and  must 
have  been  very  unwieldy,  since  we 
are  told  of  one  in  the  cathedral 
church  at  Halberstadt,  which  had 
only  a  few  large  pipes,  and  the 
keys  were  more  than  a  hand- 
breadth  in  width,  and  were  beaten 
or  pressed  down  by  the  fist,  or 
elbow ;  the  wind  being  supplied  by 
several  small  bellows.  We  are  also 
told  of  the  Winchester  organ  which 
required  seventy  men  to  supply  it 
vrith  vrind ;  its  compass  was  of  ten 


319 


ORG 


ORRERY. 


OSC 


notes  only,  although  it  had  400 
pipes,  t. e.  forty  to  each  note;  it 
was  so  loud  that  it  could  be  heard 
all  over  the  city.  The  organ  is 
usually  described  as  being  of  three 
kinds;  the  great,  or  full  chorus 
organ;  the  swell  organ,  and  the 
choir  organ :  the  latter  is  used  to 
accompany  the  softer  parts  of  the 
music,  and  is  such  an  instrument 
as  was  carried  in  the  ancient  pro- 
cessions, in  the  rogation  days,  and 
other  seasons,  to  accompany  the 
priests  with  while  chanting  the 
litanies;  the  performer,  or,  more 
properly  speaking,  the  minister  at 
the  organ,  being  carried  also  with 
the  instrument,  and  seated :  hence 
this  organ  was  called  the  chair- 
organ,  now  corrupted  into  choir- 
organ,  from  the  difference  in  its 
employment.  The  swell  organ  is 
used  chiefly  to  accompany  solos  ; 
for  interludes,  and  such  like  fanci- 
ful  music,  and  takes  its  name  from 
being  able  to  swell  out  its  sounds 
by  openings  made  by  turning  a 
series  of  boards,  on  their  centres, 
similar  to  a  Venetian  blind,  these 
boards  being  connected  by  levers 
under  the  control  of  the  per- 
former's foot. 

The  key-board,  or  row  of  keys 
of  an  organ,  are  like  those  of  a 
piano-forte,  only  they  require  to  be 
pressed  down,  (not  struck  like  those 
of  the  latter  instrument,)  so  as  to 
open  the  pallets  before  mentioned, 
and  cause  the  pipes  to  speak.  A 
complete  church  organ  contuns 
three  rows  of  keys,  one  for  each  of 
the  above-mentioned  organs ;  and 
most  organs  have  also  a  row  of 
keys  called  pedals,  to  enable  the 
organist  to  play  the  bass-notes  with 
his  feet. 

In  organs  that  are  played  by 
means  of  a  wind,  or  handle,  the 
part  of  the  organist  is  perform- 
ed by  a  cylinder,  on  which  are 
placed  a  nimiber  of  wires  so  con- 
trived as  to  press  upon  the  levers, 
and  open  the  pallets  or  valves ;  and 
hence  those  instruments  are  called 

320 


barrel  organs.  They  are  of  little 
or  no  use  for  the  purposes  of  the 
church.  It  has  been  the  fashion 
for  some  time,  to  make  one  organ 
do  the  work  of  two,  namely,  the 
full  organ  and  the  choir  organ: 
but  it  is  at  best  but  a  sorry  con- 
trivance; for  in  such  an  organ 
there  can  be  no  good  choir  organ 
mixture ;  and  the  full  organ  is  ge- 
nerally too  noisy,  the  fullness  being 
made  up  of  loud-voiced  pipes,  in- 
stead of  their  being  round,  mellow, 
and  full -toned.  These  kinds  of 
organs  have  not  the  dignified  and 
solemn  character  necessary  for  real 
church  music. 

Organ  screen^  an  ornamental  stone 
wall  or  piece  of  timber  frame-work, 
on  which  a  church  organ  is  placed, 
and  which  in  English  cathedrals 
and  churches  forms  usually  the 
western  termination  of  the  choir 

Organumt  a  name  given  to  a  n^achine 
or  contrivance  in  aid  of  the  exercise 
of  human  labour  in  architecture 
and  other  arts 

Oriel  window,  a  projecting  angular 
vnndow,  mostly  of  a  triagonal  or 
pentagonal  form,  and  divided  by 
mullions  and  transoms  into  differ- 
ent bays  and  other  proportions. 
The  word  oriel  has  been  discussed 
by  many  writers,  but  there  cannot 
be  conceived  an  architectural  charm 
more  cheerful  to  the  interior,  or 
more  decorative  to  the  exterior  of  a 
building,  than  an  oriel  vsrindow. 

Orlop,  in  shipping,  the  middle  deck 

Omithon,  an  aviary  or  poultry-house, 
or  the  appurtenance  to  a  farm  villa 

Orrery,  in  mechanics,  a  machine 
which  by  many  complicated  move- 
ments represents  the  revolutions 
of  the  heavenly  b(>dies 

Orthography,  in  architecture,  the  ele- 
vation of  a  building,  showing  all 
the  parts  thereof  in  their  true  pro- 
portions :  the  orthography  is  either 
external  or  internal.  The  external 
is  the  delineation  of  the  outer  face 
or  front  of  a  building;  the  internal 
is  a  section  of  the  same. 

Oscillating  Engine,  a  marine  engine, 


osc 


PAGODA. 


PAG 


with  a  vibrating  cylinder,  having 
the  piston-rod  connected  to  the 
crank,  and  the  cylinder  supported 
by  the  trunnions  projecting  from 
the  sides  at  or  near  the  centre, 
cast  hollow  and  connected  to  the 
steam  and  eduction  pipes 

Oscillation,  or  vibration,  in  mechanics, 
the  act  of  moving  backward  and 
fonK'ard  like  a  pendulum 

Oscillation,  the  axis  of,  in  mechanics, 
aright  line  parallel  to  the  apparent 
horizontal  one,  and  passing  through 
the  centre,  about  which  the  pen- 
dulum oscillates 

Osterly  House.  "  The  opulence  and 
gallantry  of  Sir  Thomas  Gresham 
rivalled  the  wonders  of  romance. 
Queen  Elizabeth  had  visited  that 
superb  mansion,  and  on  quitting 
the  window  to  seek  her  bed,  had 
remarked  aloud, '  How  much  more 
gracefully  the  court  yard  would 
appear  if  divided  in  two  by  a  wall.' 
The  words  were  caught  up  by  Sir 
Thomas,  who  instantly,  on  quitting 
the  royal  presence,  sent  hastily  to 
his  masons  and  bricklayers,  assisted 
them  with  innumerable  labourers, 
worked  all  the  night,  and  completed 
the  wall  according  to  the  Queen's 
wishes  before  she  had  risen  from 
her  bed.  The  courtiers  were  chag- 
rined at  the  knight's  abruptness, 
and  one  of  them  consoled  himself 
with  a  conceit,  'that  it  was  noway 
strange  that  one  who  could  build  a 


'change  could  exchange  a  build- 


PAC 

Pack,  a  quantity  of  material,  either 
wood  or  coals,  placed  or  piled  up 
to  support  roofs,  or  for  other  pur- 
poses 

Paddle-shaft,  the  shaft  upon  which 
the  paddle-wheel  is  fixed,  placed 
centrally  with,  and  connected  to, 
the  crank-shaft 

Paddle-wheel,  the  wheel  fixed  upon 

the  paddle-shaft,  for  propelling  a 

vessel  through  the  water  by  the 

action  of  a  numberof  paddle-boards 

fixed  at  the  circumference 
_ 


mg 


> »» 


Ostium,  an  inner  door,  the  door  of 
a  chamber 

Outward  angle,  the  same  as  a  salient 
angle 

Ova,  in  architecture,  ornaments  in 
the  form  of  eggs,  carved  on  the 
contour  of  the  ovolo,  or  quarter- 
round,  and  separated  from  each 
other  by  anchors  and  arrow-heads 

Oval,  a  figure  in  geometry,  bounded 
by  a  curve-line  returning  to  itself. 

Overshot -wheel,  a  wheel  driven  by 
the  weight  of  water  conveyed  into 
buckets,  disposed  on  its  circumfer- 
ence so  that  one  part  of  the  wheel 
is  loaded  with  water  while  the  other 
is  empty 

Over  story,  the  clear  story  or  upper 
story  of  a  building 

Ovolo,  a  convex  moulding,  mostly  used 
in  classical  architecture;  in  the 
Roman  examples  it  is  an  exact 
quarter  of  a  circle ;  in  Grecian  it  is 
more  flat  and  quirked  at  the  top. 
It  is  frequently  used  in  the  deco- 
rated Gothic  style. 

Oxidation,  rusting;  the  process  of 
converting  metals  and  other  sub- 
stances into  oxides,  by  combining  a 
certain  portion  of  oxygen  with  them 

Oxygen,  in  chemistry,  a  gaseous  ele- 
ment, of  great  importance  in  the 
economy  of  Nature :  it  is  essential 
to  the  maintenance  of  organic  life : 
hence  its  original  name,  *  vital  air.' 


PAG 

Pagoda,  in  architecture,  a  name  ap- 
plied by  the  Europeans  to  Hindoo 
temples  and  places  of  worship,  but 
not  by  the  Hindoos  themselves, 
who  have  no  such  appellation;  they 
are  square  stone  buildings,  not  very 
lofty,  crowned  with  a  cupola :  the 
pagodas  of  China  are,  however, 
lofty  houses,  which  sometimes  rise 
to  the  height  of  nine  stories,  of 
more  than  twenty  feet  each.  The 
buildings  are  depositories  of  their 
idols,  and  used  for  their  worship. 


PAI 


PAINTING. 


PAL 


Painted  and  Stained  Glast,  formerly 
used  exclusively  for  ecclesiasticid 
purposes,  —  displaying  devotion 
and  spiritual  bearing.  Latterly 
painted  and  stained  glass  have 
been  used  for  domestic  purposes. 
The  art  of  painting  on  glass  was 
known  as  early  as  the  sixth  century, 
and  was  applied  to  the  enrichment 
of  the  basilica  of  St.  Sophia,  and 
other  churches  in  Constantinople ; 
and  in  the  reign  of  Charlemagne 
some  progress  was  made  in  enrich- 
ing and  beautifying  glass  with 
colours.  In  the  tenth  century  it 
was  much  admired,  and  ^dvaneed 
rapidly :  Henry  II.  patronized  this 
art.  In  France  it  progressed  in  all 
the  magnificence  of  colour  and  ex- 
ecution, and  was  extensively  diffused 
in  England.  In  Canterbury  and 
York  some  beautiful  examples  re- 
main, for  the  admiration  and  ex- 
ample of  modern  practice.  Of  the 
unique  cento  style,  the  revival  of 
art  under  the  immortal  Albert 
Durer,  some  very  fine  specimens  of 
the  period,  picturesquely drawn,are 
to  be  found  in  fine  preservation  in 
St.  Jacques,  at  Li^e ;  and  of  ra- 
ther a  later  time,  those  of  the 
Crabeths,  at  Gouda,  in  Holland,  are 
magnificent  executions  of  this  art 
by  these  brothers.  One  of  these 
windows,  upwards  of  70  feet  high, 
was  executed  by  Theodore  Crabeth, 
by  command  and  at  the  expense  of 
Queen  Mary  of  England,  consort  of 
Philip  II. :  a  portion  of  the  picture 
is  magnificently  painted,  the  sub- 
ject of  which  is  the  Queen,  with  her 
husband,  kneeling  at  the  Lord's 
table.  The  upper  part  of  this  win- 
dow has  been  destroyed  by  a  storm, 
but  the  subject  referred  to  remains 
perfect,  and  exhibits  correct  like- 
nesses of  these  sovereigns. — (See 
'  Divers  Works  of  Early  Masters,' 
in  2  vols.) 

Painting,  The  art  of  painting  gives 
the  most  direct  and  expressive  re- 
presentation of  objects ;  and  it  was 
doubtless  for  this  reason  employed 
by  many  nations,  before  the  art  of 

322  


writing  was  invented,  to  commu- 
nicate their  thoughts,  and  to  con- 
vey intelligence  to  distant  places. 
The  pencil  may  be  said  to  vnrite  a 
universallanguage,for  everyone  can 
instantlyunderstand  the  meaning  of 
a  painter,  provided  he  be  faithful  to 
the  rules  <^  his  art :  his  skill  enables 
him  to  display  the  various  scenes 
of  nature  at  one  view,  and  by  his 
delineations  of  the  striking  effects 
of  passion,  he  instantaneously  af- 
fects the  soul  of  the  spectator.  In- 
vention  in  painting  consists  prin- 
cipally  in  three  thungs :  first,  the 
choice  of  a  subject  properly  within 
the  scope  of  the  art ;  secondly,  the 
seizure  of  the  most  striking  and 
energetic  moment  of  time  for  re- 
presentation ;  and,  lastly,  the  dis- 
coveryand  selection  of  such  objects, 
and  such  probable  incidental  cir- 
cumstances,  as,  combined  together, 
may  best  tend  to  develop  the  story 
or  augment  the  interest  of  the 
piece. 

Architects  will  often  find  deco- 
rations of  a  room  and  its  furniture 
well  worthy  of  their  study.  In 
houses  recently  built,  both  in  town 
and  country,  the  taste  of  the  archi- 
tect has  be^n  called  in,  to  give 
designs  for  the  arrangenxent  of 
curtains,  for  grates,  pier  tables, 
chairs,  and  so&s ;  and  in  many  in- 
stances the  superior  chasteness  of 
the  designs,  and  the  harmony  of 
the  whole  with  the  architectural 
style  of  the  rooms,  may  be  seen, 
conformable  with  the  different  uses 
to  which  the  rooms  are  appro- 
priated. 

Painter y  in  navigation,  a  sea  term  for 
a  rope  employed  to  fasten  a  boat 
to  the  ship,  wharf,  &c. 

Pakutraf  a  building  appropriated  to 
gymnastic  sports 

Palaces  of  Persia  (the  royal  country) 
are  at  this  day  castellated,  and  many 
villages  have  towers  of  defence 

Pale,  in  heraldry,  the  third  and  middle 
part  of  the  escutcheon 

Palieanderf  a  name  used  on  the  con- 
tinent for  rose-wood 


PAL 


PARABOLA. 


PAR 


Pall,  in  heraldry,  denotes  a  tort  of 
cro88y  representiiig  the  pallium  or 
archiepiscopal  <Miuuneiit  sent  from 
Rome  to  metropolitans 

Palbf  in  ship-buUding,  strong  short, 
pieces  of  iron  or  wood,  placed  near 
the  capstan  or  windlass,  so  as  to 
prevent  their  recoiling 

Pattadiumf  a  metal  found  with  platina, 
but  in  small  quantity 

Pattadium,  in  antiquity,  a  wooden 
image  of  the  goddess  Minerva  or 
Palks,  the  possession  of  which 
involved  the  fate  of  Troy 

PalHum  or  Pattf  in  church  rituals,  a 
pontifical  ornament  worn  by  popes, 
patriarchs,  primates,  and  metn^- 
htans  of  the  Roman  church,  in  the 
form  of  a  fillet  of  black  siUc,  over 
the  shoulders,  with  four  red  crosses 

Pabn-treeSf  wood  of  great  variety, 
imported  from  the  East  and  West 
Indies,  but  sparingly  employed  in 
England  for  cabinet  and  marquetry 
work,  and  sometimes  for  billiard- 
cues,  &c. 

Palette  (French),  in  painting,  a  light 
board  on  which  the  colours  are 
held 

Pabgravef  in  heraldry,  a  count  or  earl, 
who  has  the  overseeing  of  a  palace 

Paine,  the  light  of  a  window;  for- 
merly  applied  also  to  the  sides  of  a 
tower»  turret,  spire,  &c. 

Panel,  in  carpentry,  &a,  a  square 
piece  of  any  matter  inserted  be- 
tween other  bodies ;  sunken  com- 
partments of  wainscoting,  ceilings, 
&&,  principally  employed  in  Gothic 
and  Domestic  architecture  for  in- 
terior fittings 

Ptmei,  a  space  or  compartment  in 
a  wall,  generally  of  English  or 
Flemish  oak,  and  on  a  ceiling, 
enclosed  within  a  raised  margin 

Panel,  in  mining,  a  heap  of  ore 
dressed  and  ready  for  sale 

Panemore,  in  mechanics,  a  globular 
wind-nidll,  proposed  to  be  erected 
in  the  centre  of  a  ship,  for  turning 
wheels  and  paddles* 

Parufpfyjin  heraldry, complete  armour 

Panorama  C^uU  viewj,  in  painting, 
a  picture  drawn  on  the  interior 

■       323 


surfiice  <^  a  large  cylinder,  rej^e- 
senting  the  objects  that  can  be 
seen  from  one  station  when  the 
observer  directs  his  eye  successively 
to  every  point  of  the  horizon 

Pmitheon,  a  temple  dedicated  to  all 
the  gods;  one  of  the  most  eele- 
brat^  edifices  of  Rome 

Panioffrqph,  in  mechanics,  an  instru- 
ment contrived  for  the  purpose  of 
copying  drawings,  so  that  the  copy 
may  be  either  similar  to  or  larger 
or  smaller  than  the  originaL  (See 
PeiUagraph.) 

Para,  in  Comkh  minings  a  gang  or 
party  of  men 

ParabolOf  one  of  the  conic  sections 
formed  by  the  intersection  of  a 
plane  and  a  cone  when  the  plane 
passes  parallel  to  the  side  of  the 
cone 

Parabolic  Pframidoid,  a  solid  gen- 
erated by  supposing  all  the  squares 
of  the  ordinates  applicable  to 
the  parabola  so  placed  that  the 
axis  shall  pass  through  all  their 
centres  at  right  angles,  in  which 
case  the  aggregate  of  the  planes 
will  form  the  solid  called  the  para- 
boUc  pyramidoid,  the  solidity  of 
which  is  equal  to  the  product  of 
the  bases  and  half  the  altitude 

Paraboloid  or  Paraiolie  Conoid,  the 
solid  generated  by  the  rotation 
of  parabola  about  its  axis,  which 
remains  fixed.  A  frustrum  of  a  pa- 
raboloid is  the  lower  solid  formed 
by  a  plane  passing  parallel  to  the 
base  of  a  paraboloid. 

ParaboUe  spindle,  the  solid  gene- 
rated by  the  rotation  of  a  parabolas 
about  any  double  ordinate 

Paradise,  a  private  apartment,  a  study, 
the  private  appurtenances  to  a  con- 
vent 

Paradromides,  hypaethral  walks,  at- 
tached to  the  Greek  palaestra.  The 
Romans  called  these  walls  xysta ; 
whereas  the  xysta  of  the  Greeks 
were  covered  porticoes,,  in  which 
the  athletse  exercised  in  winter 

PardUel,  m  geometry,  is  appUed  to 
lines,  figures,  and  bodies  which  are 
every  whore  equidistant  from  each 


PAR 


PARTRIDGE  WOOD. 


PAR 


other,  or  which,  if  ever  so  far  pro- 
daced,  would  never  meet 

Parallel  bars,  the  rods  parallel  to  the 
centre  line  of  a  heam,  joining  the 
connecting  links  at  the  lower  ends. 

Parallel  motion,  the  connection  be- 
tween the  top  of  the  piston-rod  and 
the  beams :  a  name  given  to  a  con- 
trivance, invented  by  James  Watt, 
for  converting  a  reciprocating  cir- 
cnlar  motion  into  an  alternating 
rectilinear  motion 

Parallel  ruler,  an  instrument  consist- 
ing of  two  wooden,  brass,  or  steel 
rulers,  equally  broad  throughout, 
and  so  joined  together  by  the  cross 
blades  as  to  open  to  different  inter- 
vals, and  accede  and  recede,  yet 
still  retaining  their  parallelism 

Parallelogram,  in  geometry,  a  quad- 
rilateral right-lined  figure  whose 
opposite  sides  are  pandlel 

Parallelogram  of  forces  is  a  phrase 
denoting  the  composition  of  forces, 
or  the  finding  a  single  force  that 
shall  be  equivalent  to  two  or  more 
given  forces  when  acting  in  given 
directions 

Parallelopiped,  in  geometry,  a  regular 
solid,  contained  under  six  paraUelo- 
grams,  the  opposite  of  which  are 
equal  and  parallel;  or  it  is  a  prism 
whose  base  is  a  parallelogram:  it  is 
always  triple  to  a  pyramid  of  the 
same  base  and  height 

Parament,  the  furniture,  ornaments, 
and  hangings  of  an  apartment  for 
a  room  of  state 

Parameter,  a  constant  right  line  in 
each  of  thethree  conic  sections,  and 
otherwise  called  latus  rectum,  be- 
cause it  measures  the  conjugate 
axes  by  the  same  ratio  which  has 
taken  place  between  the  axes  them- 
selves, being  always  a  third  pro- 
portion of  them 

Parapet,  the  upper  part  of  a  house, 
which  is  above  the  springing  of  a 
roof,  and  guards  the  gutter;  the 
upper  part  of  a  wall,  a  bridge,  a 
terrace,  or  balcony,  &c.  Parapets 
around  the  flat  roofs  of  houses  in 
the  East  are  of  the  most  ancient 
date.    '*  When  thou  buildest  a  new 

324 


house,  then  thou  shalt  make  a  bat- 
tlement for  thy  roof,  that  thou  bring 
not  blood  upon  thine  house,  if  any 
manfall  from  thence. — Deu/.xxii.  8. 

Parascenmm,m  ancient  theatres,  a 
place  behind  the  scenes  to  which 
the  actors  withdrew  to  dress  and 
undress  themselves 

ParastakB,  square  columns,  or  antae ; 
called  also  parastades  andparasta- 
licse.  Yitruvius  uses  the  term  to 
signify  the  square  posts  placed  be- 
hind the  columns  of  the  basilica, 
for  the  support  of  the  floors  of  the 
upper  porticoes 

Pargeting,  parge-work,  plaster-work, 
employed  exteriorly  for  timber 
houses,  as  an  ornament;  used  also 
in  plain  and  ornamental  work,  for 
both  the  exterior  and  interior 

Paries,  the  walls  of  a  Grecian  house, 
in  contradistinction  to  the  wall  of  a 
city ;  a  small  enclosure,  such  as  a 
court  yard 

Parlour,  B.  private  apartment  in  a 
dwelling,  usually  on  the  ground 
floor;  a  speaking-room  in  a  con- 
vent. In  the  time  of  Henry  VIII. 
parlours  and  privy  rooms — summer 
parlours,  vrinter  parlours — were 
well,  comfortably,  and  conveniently 
furnished;  a  proof  that  the  gentry 
of  that  period  were  not  quite  so  far 
behind  the  present  race  as  might  be 
supposed- 

Parsonage-house,  a  residence  of  the 
incumbent  of  a  parish,  a  building 
in  the  vicinity  of  a  church 

Patera,  a  round  dish,  plate,  saucer, 
or  goblet 

Patina,  a  basin  or  bowl  of  earthen- 
ware, rarely  of  bronze 

Parthenon,  in  architecture,  the  tem- 
ple of  Minerva  at  Athens 

Particle,  the  minute  part  of  a  body, 
or  an  assemblage  of  several  atoms  of 
which  natural  bodies  are  composed 

Partners,  in  naval  architecture,  are 
thick  pieces  fitted  into  a  rabbet  in 
the  mast  carlings,  to  receive  the 
wedges  of  the  mast;  likewise  tem- 
porary pieces  nailed  on  the  deck 
round  the  pumps 

Partridge  wood  is  the  produce  of  the  I 


PAR 


PATENTS  FOR  INVENTIONS. 


PAT 


Brazils  and  the  West  India  Islands: 
it  is  sent  in  large  planks,  or  in 
round  and  square  logs.  It  was 
formerly  employed  in  the  Brazils 
for  ship-building,  and  is  known  in 
dockyards  as  cabbage-wood. 

ParfyAoaUM  are  partitions  of  brick 
made  between  buildings  in  sepa- 
rate occupations^  for  preventing  the 
spread  of  fire.  These  are  made 
thicker  than  the  external  walls; 
and  their  thickness,  and  the  neces- 
sity of  their  use,  are  regulated  by 
Act  of  Parliament,  and  specified  in 
some  of  the  clauses  of  the  Buildings 
Act  passed  in  the  reign  of  the 
present  Queen. 

Parvite^  a  porch;  an  open  area  be- 
fore the  entrance  of  a  church 

Ptuehal,  a  stand  or  candlestick,  of  a 
large  size,  used  in  Roman  Catholic 
worship 

Paaigrt^hy,  the  art  of  uniyersal 
writing 

Passantt  in  heraldry,  a  term  applied 
to  an  animal  in  a  shield  appearing 
to  walk  leisurely :  for  most  beasts, 
except  lions,  the  word  tripping  is 
frequently  used  instead  of  pat' 
sant 

Pasiionf  in  painting,  imphes  an  emo- 
tion of  the  body,  attended  with 
certain  ezpressiYe  lines  in  the  face, 
denoting  an  agitation  of  soul 

Pasiici,  or  ImUatUms  in  Painting», 
Teniers  understood  the  union  of 
colours  extremely  well,  yet  Bassan 
was  superior  to  him  in  the  sweet- 
ness and  figour  of  his  tints.  De 
Pile  recommends  it  to  all  persons 
who  would  not  wish  to  be  deceived 
by  pastid,  to  compare  the  taste  of 
design,  the  colouring  and  the  cha- 
racter of  the  pencil,  with  the  ori- 
ginals. Teniers,  Giordano,  and 
Bon  BouBoque  are  those  who 
have  appeared  with  the  greatest 
reputation  for  inutating  other  great 
masters ;  and,  beside  these,  many 
other  artists  hare  employed  them- 
selyes  in  painting  pastid. 

Pattoral  9ioff^  the  official  staff  of  an 
ardibishop,  a  bishop,  or  mitred 
abbot 

325 


Patandy  the  bottom  plate  or  sOl  of  a 
partition  of  a  screen 

Patefgf  a  small  plate  or  salver  used  in 
the  celebration  of  the  eucharist 

Patentt  for  Inventioru  are  public 
grants  to  the  inventors  of  new 
and  useful  machinery  and  processes 
in  the  arts,  and  by  which  cer- 
tain privileges  are  secured  to  the 
'inventors,  for  the  exclusive  use 
and  exercise  of  thdr  inventions 
during  a  limited  period.  Patents 
are  therefore  monopolies  of  a  de- 
finite character;  but  being  de- 
signed as  a  security  for  the  reward 
of  those  whose  ingenious  faculties 
and  practical  skill  have  produced 
inprovements  of  general  utility  and 
vidne,  these  monopolies,  if  justly 
granted  and  honestly  exerdsed,  are 
not  to  be  decried  as  injurious  to 
the  public  interests,  but  should  be 
conceded  with  vrillingness,  and 
command  the  liberal  protection  of 
the  community,  which  is  destined 
to  reap  a  conthiual  and  permanent 
advantage  from  the  improvements 
thus  fostered  in  their  infant  de- 
vdopment.  Patents  for  inventions 
shoidd  therefore  be  admitted  as 
bargains  between  the  inventor  on 
the  one  hand,  and  the  public  on 
the  other ;  and  the  abuses  to  which 
these  bargains  are  liable  arise  from 
the  common  causes  of  official  cor- 
ruption and  individual  cupidity  and 
jealousy. 

The  lavrs  under  which  patents 
are  granted  vary  in  their  form  in 
the  several  European  and  American 
States,  and  are  all,  in  some  degree, 
imperfect,  and  ineffective  of  their 
proper  object. 

In  Great  Britain  and  Ireland, 
Letter*  Patent  {fovoided  on  statutes 
from  the  18th  of  Henry  YL,  but 
mainly  on  the  2l8t  of  James  I. 
c.  3)  are  granted  by  the  Crovm, 
onbehalf  of  the  public,  to  the  inven- 
tor of  any  manner  of  new  manufoc- 
ture,  for  the  sole  privilege  to  make, 
use,  exercise,  and  vend  his  said  in- 
vention, during  the  term  of  fourteen 
years ;  and  an  inventor,'  as  thus 


PAT 


PATENTS  FOR  INVENTIONS. 


PAT 


privileged,  may  be  the  first  inventor 
absolutely,  the  first  jmbluher  if 
others  have  also  made  the  same 
invention,  or  the  first  in^iMirter  from 
abroad,  into  these  realms,  of  an 
invention  not  previously  herein  used 
and  exerdsed.  British  patents  are 
granted  as  matters  of  course,  pro- 
vided certain  legal  forms  are  duly 
complied  with,  certain  official  fees 
(which  are  very  high)  are  duly 
paid,  and  the  legal  advisers  of  the 
Crown  (the  Attorney  or  Solicitor 
General)  are  not  required  by  op- 
posing parties  to  discover  that  the 
privilege  sought  will  interfere  with 
any  contemporary  application. 

The  several  processes  in  solicit, 
ing  a  British  patent  are  as  follow : 
The  inventor  has  to  petition  the 
Crown  to  grant  letters  patent  for 
his  invention,  of  which,  at  this 
stage,  he  states  only  the  title ;  and 
he  accompanies  his  petition  vrith  a 
declaration  of  the  grounds  of  his 
request,  and  the  provinces  in  which 
he  wishes  to  secure  his  patent 
right.  These  documents  are  lodged 
at  the  office  of  the  Secretary  of 
State  for  the  Home  Department, 
whence  they  are  referred  to  the 
Attorney  or  Solicitor  General, — ^the 
selection  of  either  of  these  officers 
being  with  the  inventor.  If  no 
opposition  occur  therefrom  eaveatSi 
(which  are  formal  notices  that  any 
one  may  enter,  to  be  informed  of 
applications  for  patents,)  one  of 
those  officers  makei  a  report  on 
the  petition,  and  recommends  that 
letters  patent  be  granted  thereon, 
provided  the  petitioner  enrol  the 
necessary  specification,  &c.  within 
the  time  Umited  by  the  statute. 
This  report  is  taken  to  the  Secre- 
tary of  State's  office,  for  the  Royal 
warrant,  directing  the  bill  to  be 
prepared  for  the  Royal  signature. 
The  warrant  is  committed  to  the 
Attorney-General,  and  if  not  op- 
posed, he  prepares  the  bill,  which 
is  signed  at  the  Secretary  of  Statie*s 
office.  Under  Royal  warrant,  sealed 
with  the  Royal  signet,  the  bill  re- 

326 


ceives  the  privy  seal,  and  is  then 
directed  to  the  Lord  Chancellor  for 
letters  patent  to  be  made  out  and 
sealed  with  the  great  seaL  From 
this  practice,  that  of  soliciting 
patents  for  Scotland  and  Ireland 
differs  only  in  minor  details,  the 
oonunon  feature  of  the  anxnge- 
ment  being  that  of  a  multiplicity 
alike  of  forms  and  fees,  which  en- 
hance the  trouble  and  eipense, 
without  promoting  the  effidency 
or  security  of  the  system. 

Having  obtained  the  great  seal, 
the  patentee  is  allowed  a  period  of 
six  months  to  complete  his  experi- 
ments, and  to  have  his  specifica- 
tion (and  drawings,  if  required,) 
prepared.  For  this  purpose,  great 
care  and  judgment  are  neeided, 
based  on  a  knowledge  of  former 
patents,  to  frame  the  specification 
so  that  it  shall  ex^ain  with  suffi- 
cient clearness  the  precise  nature 
of  the  improvements,  and  have 
that  value  as  property,  which  a 
good  specification  of  a  patent 
always  has.  On  or  before  the  last 
day  of  the  allotted  six  months,  the 
specification  must  be  duly  enrolled, 
and  the  patentee  receives  an  official 
certificate  of  its  enrolment.  The 
patent  is  now  complete^  and  the 
patentee  can  safely  proceed  to 
practise  under  it. 

By  a  comparatively  recent  statute 
(5  and  6  William  IV.  c.  83),  a 
patentee  is  now  enabled,  under  the 
authority  of  the  Attorney  or  So- 
licitor General,  to  amend  his  title 
and  specification  subsequenUy;  if 
necessary,  to  correct  one,  to  make 
it  consistent  with  the  other,  and,  in 
fact,  to  disclaim  part  or  parts  of  his 
daims,  which  he  may  have  since 
found  to  be  untenable.  Under  the 
same  statute  also,  the  inventor  may 
petition  for  a  prolongation  oi  his 
term  of  fourteen  years;  which 
petition  is  referred  to  the  Judicial 
Committee  of  the  Privy  Council, 
who  grant  the  same  if  the  petitioner 
makes  out  a  case,  satisfactory  to 
them,  of  extraordinary  losses,  de- 


PAT 


PATENTS  FOR  INVENTIONS. 


PAT 


lays,  or  other  special  reasons  for 
the  prolongation. 

The  property  in  a  patent  can  he 
defended  from  infringement  hy  a 
hill  in  equity,  or  action  at  law.  It 
may  he  assigned,  in  whole  or  part, 
hy  the  patentee  to  any  number 
not  exceeding  twelve  persons.  It 
may  he  mortgaged  to  any  numher 
of  persons;  and  a  patentee  can 
also  grant  licences  for  the  use  of 
his  patent,  in  a  variety  of  modes, 
to  an  unlimited  numher  of  persons. 

The  C08t  of  obtaining  a  patent, 
including  fees  for  agency,  if  un- 
opposed, is  for  England,  JSllO; 
for  Scotland,  £80 ;  and  for  Ireland, 
£  135.  If  the  patent  he  granted 
to  two  or  more  persons  jointly, 
which  it  may  he,  extra  fees  are 
charged  for  the  additional  names ; 
and  if  the  Channel  Islands  of 
Guernsey,  Jersey,  Aldemey,  Sark, 
and  Man,  and  the  British  Colonies 
and  Plantations  abroad,  are  in- 
cluded, a  further  expense  of  about 
seven  guineas  is  incurred.  To  these 
items  should  he  also  added  the 
cost  of  preparing  and  copying  spe- 
cification and  drawings,  the  charges 
forwhich  are  of  course  very  variable, 
according  to  length,  intricacy,  &c. 

The  expenses  and  regulations 
under  which  the  foreign  patents 
are  granted  vary  considerably.  The 
following  brief  epitome  must  suffice 
in  this  place. 

In  the  United  States  of  America, 
patents  are  granted  only  to  the 
absolute  inventor,  always  for  four- 
teen years,  and  are  granted  or 
withheld  at  the  option  of  the  Go- 
vernment Commissioners  of  Pa- 
tents. The  amount  of  official  fees 
payable  depends  upon  the  country 
of  which  the  applicant  is  a  native. 
Thus,  a  citizen  of  the  United 
States,  or  a  foreigner  who  has 
resided  in  the  States  one  year  next 
preceding  the  application,  and  has 
mode  oath  of  his  intention  to  he- 
come  a  citizen,  pays  a  fee  of  '8*30 ; 
a  tubject  qf  the  Sovereign  of  Great 
Britain,   '8*500;   and  any   other 

327 


fordgner,  ^300.  If  the  applica- 
tion for  a  patent  be  rejected  by  the 
Commissioner,  two-thirds  of  the 
fees  paid  are  returnable. 

In  France,  patents  for  inventions 
are  granted  alike  to  natives  and 
foreigners,  and  the  duration  of  the 
privilege  may  be  fixed  hy  the  pa- 
tentee at  five,  ten,  or  fifteen  years, 
the  amount  of  tax  being  propor- 
tional to  the  term,  namely,  500 
francs  for  five  years ;  1000  francs 
for  ten  years;  and  1500  francs  for 
fifteen  years ;  payable  by  annual  in- 
stalments of  100  francs.  The  pa- 
tentee thus  enjoys  the  power  of 
relinquishing  his  inventi(m,  if  found 
unprofitable,  at  any  time  during 
the  intended  term,  by  ceasing  to 
pay  the  annual  instalment  of  fees. 

In  Belgium,  patents  are  granted 
for  five  or  ten  years :  imported  in- 
ventions are  patentable,  and  the 
whole  of  the  Government  tax, 
which  is  not  heavy,  may  remain 
unpaid  until  the  expiration  of  two 
years  from  the  grant. 

In  Holland,  patents  are  granted 
for  five,  ten,  or  fifteen  years,  and 
may  he  had  for  foreign  as  well  as 
native  inventions.  The  fees  for  a 
patent  for  five  years  are  150 
guilders,  or  £12.  10«.;  and  for 
.  terms  of  ten  or  fifteen  years  they 
vary  from  300  to  750  guilders,  or 
[.from  £25  to  £62.  10«. 

In  Prussia,  Russia,  &c.,  the  Go- 
vernments exercise  a  discretionary 
power  in  granting  or  refusing  pa- 
tents, and  the  laws  are  of  a  strin- 
gent and  arbitrary  character. 

In  Austria,  patents  are  granted 
for  terms  from  five  to  fifteen  years ; 
the  taxes  must  be  paid  when  the 
application  is  made,  and  the  in- 
vention put  in  practice  vrithin  one 
year  from  the  date  of  the  grant. 

The  German  and  Italian  States 
have  patent  laws  peculiar  to  them- 
selves, hut  generally  similar  to 
those  already  described. 
Patent  yellow,  Tumer^a  yellow,  or 
MontpelUer  yellow,  is  a  submuriate 
or  chloride  of  lead,  which  metal 


PAT 


PEDIMENT. 


PED 


is  the  basis  of  the  most  opaque 
yellow  pigment :  it  is  a  hard,  pon- 
derous,  sparkling  substance,  of  a 
crystalline  texture  and  bright  yel- 
low colour,  hardly  inferior,  when 
ground,  to  chromic  yellow.  It  has 
an  excellent  body,  and  works  well 
in  oil  or  water,  but  is  soon  injured, 
both  by  the  sun's  light  and  impure 
air ;  it  is  therefore  little  used,  ex- 
cept for  the  common  purposes  of 
house-painting,  &c. 

Patera^  a  circular  flat  ornament,  used 
in  Classical  architecture ;  used  also 
in  Gothic  and  Italian  architecture 

Pan/,  the  catch  which  holds  a  ratchet- 
wheel,  allowing  it  to  turn  in  one 
direction  only 

PaviHon,  in  architecture,  a  detached 
building ;  an  insulated  turret,  con- 
tained under  a  single  roof,  some- 
times square  and  sometimes  dome- 
formed;  named  from  its  resem- 
blance to  the  roof  of  a  tent.  The  late 
palatial  monstrosity  at  Brighton  was 
called  a  pavilion. 

Pax,  a  small  tablet,  having  on  it  a 
representation  of  the  crudflxion,  or 
some  other  Christian  symbol,  of- 
fered to  the  congregation  in  the 
Romish  church,  to  be  kissed  in  the 
celebration  of  the  mass?  it  was 
usually  of  silver,  or  other  metal, 
with  a  handle  at  the  back,  but  was 
occasionally  of  other  materials ; 
sometimes  it  was  enamelled,  and 
set  with  precious  stones 

Peach' stone,  a  blueish  -  green  soft 
stone 

Peari  white.  There  are  two  pigments 
of  this  denomination :  one,  fahely 
so  called,  prepared  from  bismuth, 
which  turns  black  in  sulphuretted 
hydrogen  gas  or  any  impure  air, 
is  employed  as  a  cosmetic:  the 
other  is  prepared  from  the  waste 
of  pearls  and  mother-of-pearl, 
is  exquisitely  white,  and  of  good 
body  in  water,  but  of  little  force 
in  cJl  or  varnish;  it  combines,  how- 
ever,  with  aU  other  colours,  with- 
out injuring  the  most  delicate,  and 
is  itself  perfectly  permanent  and 
innoxious. 


Pear-tree,  a  native  European  wood; 
its  colour  is  a  light  brovni,  some- 
thing of  a  pale  mahogany  or  cedar : 
it  is  employed  by  the  Tunbridge 
turners 

Peastone,  or  pieoUte,  in  mineralogy, 
pisoform  limestone 

Peat,  in  mineralogy,  a  substance  con- 
sisting of  the  twigs,  leaves,  and 
roots  of  trees,  mixed  vrith  grass, 
straw,  plants,  and  weeds,  that  have 
laid  Icmg  in  water,  and  become  con- 
verted into  a  blackish-brown  mass 
that  may  be  cut  with  a  spade,  and 
dried  for  fuel 

Pedestal,  in  architecture,  the  lower 
member  of  a  pillar,  named  by  the 
Greeks  stylobates  and  stereobates ; 
also  the  basis  of  a  statue.  In  Chu>. 
sical  architecture  it  consists  of 
three  divisions :  the  base,  or  foot, 
next  the  ground,  the  dado,  form- 
ing the  main  bpdy,  and  the  cor- 
nice, or  sur-base  moulding,  at  the 
top. 

Pediment,  the  triangular  plane  or  sur- 
face formed  by  the  vertical  ter- 
mination of  a  roof  consisting  of 
two  sloping  sides ;  consequently  it 
so  far  corresponds  with  the  gakle, 
but  in  other  respects  differs  vridely 
from  it.  One  material  difference  be- 
tween them  is,  that  whereas  the 
gable  has  no  cornices,  the  pediment 
is  bounded  by  three,  viz.  a  horizon- 
tal one,  beneath  it,  forming  its  base, 
and  two  sloping  or  raking  ones,  as 
they  are  technically  termed^;  and  the 
triangpilar  space  or  surface  included 
withm  them  is  distinguished  by 
the  name  of  the  tynqfonum  of  the 
pediment.  Another  marked  diffier- 
ence  between  them  is,  that  the 
gable  may  be  of  any  pitch;  and 
being  merdy  a  continuation  of  the 
wall  below,  instead  of  being,  like 
the  pediment,  separated  frx>m  it  by 
any  horizontal  mouldings,  its  pro- 
portions do  not  at  all  depend  upon 
the  height  or  width  of  the  firont  or 
compartment  of  the  frent  which  it 
terminates,  but  may  be  an  equila- 
teral  triangle,  or  even  considerably 
more,  as  to  height,  and  is,  besides. 


328 


PED 


PEDIMENT. 


PED 


in  nowise  governed  by  the  height  oi 
what  is  beneath  it.   The  pediment, 
on  the  contrary,  must  be  propor- 
tioned to  the  heiffht  of  the  order 
which  it  crowns ;  consequently  its 
pitch  must  be  decreased  in  some- 
what the  same  ratio  as  its  length 
or  base  is  increased,  or,  in  other 
words,  the  greater  the  number  of 
columns  beneath  a  pediment,  the 
lower  must  the  pitch  of  the  lat- 
ter be.     Hence  it  is  hardly  pos- 
sible to  pUoe  more  than  eight,  or, 
at  the  utmost,   ten  columns  be- 
neath a  pediment,  without  making 
the  pediment  either  too  low  in 
itself,  or  else  too  lofty  and  heavy 
a  mass  in  comparison  with  the 
columns  beneath  it;  thereby  not 
only  overloading  them — the  co- 
lumns being  proportioned  to  their 
entablature   {done  —  but  also  di- 
minishing their  importance,  and 
causing  the  order  itself  to  look 
almost  puny  and  meagre,  while  the 
pediment  looks  heavy  and  clumsy. 
There  has  been  a  good  deal  of 
mystification    about    determining 
the  proportion  of  pediments,  and 
special  methods  have  been  devised 
for  that  purpose,  which,  however 
ingenious  in  themselves,  as  such, 
are  any  thing  but  artistic,  or  cal- 
culated   to   secure  pleasing  pro- 
portions.     Discarding    all    such 
methodsy  it  may  be  laid  down  as  a 
safe  general  rule,  that  the  height 
of  the  tympanum  should  accord 
pretty  nearly  with  that  of  the  enta- 
blature beneath  the  pediment,  and 
not  greatly  exceed  it,  under  any 
circumstances.     Such  is  the  pro- 
portion which  Wilkins  appears  to 
have  observed  for  the  pediment  of 
the   London   University   College; 
and  although  that  building  has  a 
decastyle    portico,   the   pediment 
does  not  appear  too  low,  whereas 
that  of  the  National  Gallery  is  so, 
the  height  of  the  tympanum  being 
there  less  than  that  of  the  entabla- 
ture, notwithstanding  that  the  por- 
tico is  octastyle. 

The  ancients  generally  made  the 


pediment  contribute  largely  to  the 
embellishment  of  the  structure,  by 
sculpturing  its  tympanum  with 
figures  in  high  relief,  and  in  some 
instances  by  setting  it  back,  and 
placing  entire  statues  against  it; 
and  for  such  display  of  sculpture 
the  pediment  eminently  recom- 
mends itself,  both  by  its  conspicu- 
ous situation,  and  by  offering  a  far 
ampler  surface  for  such  purpose 
than  any  other  part  of  the  edifice ; 
one,  moreover,  which  not  only  re- 
quired a  higher  decoration,  for  the 
sake  of  consistency,  but  an  in- 
creased degree  of  it,  in  order  to 
produce  artistic  climax  and  com- 
pletion. Yet  it  must  be  confessed 
that  if  its  rittMtion  marks  out  the 
pediment  as  a  very  proper  place  for 
making  a  display  of  decoration,  its 
shape  is  by  no  means  well  adapted 
for  a  composition  of  figures,  ex- 
cept  it  be  that  it  compels  them  to 
be  arranged  symmetrically,  and  the 
principal  one  to  be  directly  in  the 
centre.  Be  the  subject  what  it 
may,  the  figures  must  always  be 
disposed  in  nearly  the  same  man- 
ner, and  not  only  very  convention- 
ally but  very  forcedly,  particularly 
towards  the  extremities, — an  incon- 
venience that  might  be  easily  over- 
come by  confining  the  figures  to  the 
centre  of  the  tympanum,  putting 
there  a  group  of  three  or  five,  and 
either  leaving  the  rest  of  the  tri- 
angular space  to  be  quite  plain,  or 
else  filling  it  up  vnth  mere  orna- 
ment. While  this  would  certainly 
be  a  rather  less  expensive  mode 
than  that  now  practised,  and  an 
equally  rational  one,  its  not  having 
been  adopted  before  ought  to  be 
itself  some  recommendation  of  it, 
as  being  a  laudable  infringement 
of  copyism,  conventionalism,  and 
routine. 

Besides  sculpture  within  them, 
pediments  are  frequently  surmount- 
ed at  their  angles  and  apex  with 
ucroteria,  namely,  low  pedestals, 
upon  which  are  placed  either  single 
figures  or  groups,  or  else  vases. 


329 


PED 


PEDIMENT. 


PED 


trophies,  or  other  omaments ;  an 
example  of  which  is  famished  by 
Spencer  House,  in  the  Green  Park, 
and  still  more  strikingly  by  the 
portico  of  the  East  India  House. 
The  practice  of  placing  statues  upon 
pediments  appears  to  have  origi- 
nated with  the  Romans,  and  is 
somewhat  analogous  in  taste  to 
that  of  putting  them  on  the  sunmiit 
of  monumental  columns;  for  in  such 
situations  human  figures  show  only 
in  their  general  mass  as  sculptural 
accessories  to  the  structure,  and  at 
a  little  distance,  or  as  seen  in  a  ge- 
neral view  of  the  building,  produce 
scarcely  more  effect  than  so  many 
pinnacles,  which  last  are  infinitely 
more  characteristic  of  Gothic  ar- 
chitecture than  in  accordance 
with  the  character  of  a  classical 
portico. 

In  Italian  and  modem  architec- 
ture generally,  the  pediment  is  em- 
ployed as  mere  decoration  in  com- 
positions for  the  dressings  of  both 
doors  and  windows,  which  prac- 
tice, like  that  of  applying  columns 
for  the  same  purpose,  has  been 
condemned  by  some  in  the  most 
unqualified.manner;  and  one  writer 
has  vituperated,  and  endeavoured 
to  bring  it  into  disgrace,  by  com- 
paring pediments  over  doors  and 
windows  to  —  cocked  hats  1  The 
resemblance  which  he  perceives, 
or  fancies,  between  a  cocked  hat 
and  a  pediment  is  not  a  particu- 
larly flattering  one ;  but  if  it  exists 
at  all,  the  injurious  comparison 
holds  equally  good  with  regard  to 
a  large  pediment  as  a  small  one ; 
therefore,  whether  it  be  that  over  a 
portico  or  over  a  window,  the  shape 
itself  is,  in  either  case,  the  most 
unfortunate  one  of  a  cocked  hat ; 
yet,  as  cocked  hats  are  now  gone 
quite  out  of  fashion,  the  unlucky 
resemblance  to  them  is  not  at  all 
likely  to  be  detected.  In  matters 
of  decoration,  some  latitude — some 
little  departure  from  strict  archi- 
tectural logic— is  allowable;  other- 
wise a  very  great  deal  in  Italian  or 

330  '  ~ 


modem  architecture  must  be  pro- 
nounced decidedly  faulty.  If  it 
be  a  solecism  to  place  pediments 
whose  forad  is  derived  from  that  of 
a  roof,  over  windows,  or  where  no 
roof  exists,  the  same  objection  lies 
against  applying  entablatureswhose 
cornices  resemble  the  horizontal 
ones  of  a  roof,  to  mere  openings  in 
the  wall ;  and  in  like  manner,  if  it 
be  a  gross  impropriety  to  flank 
windows  with  small  colnmna,  it 
must  be  as  great,  if  not  a  greater 
one,  to  introduce,  merely  for  the 
sake  of  decoration,  a  large  order 
whose  columns  are  partly  buried 
in  the  wall,  and  support  nothing 
but  an  entablature,  or  pieces  of  it, 
wholly  unnecessary  in  themselves, 
and  put  there  only  that  the  columns 
may  appear  to  support  something. 
Again,  as  to  the  objection  which 
has  sometimes  been  urged  against 
pediments  over  doors  vrithin  a 
building,  namely,  those  intended 
to  throw  off  rain,  they  should  be 
introduced  only  in  external  situa- 
tions,— it  partakes  of  the  same  kind 
of  hypercritidsm  as  the  other ;  or, 
if  strict  ratUmdUty  is  to  be  uni- 
formly enforced  in  architectural 
design,  we  must  condemn  a  great 
deal  in  the  Gothic  style  as  bdng 
exceedingly  licentious  and  irra- 
tional ;  for  in  that  we  find  a  great 
many  members  and  features  origi- 
nating in  forms  invented  for  piu*- 
poses  of  actual  service  externally, 
converted  into  mere  interior  de- 
coration; for  instance,  embattle- 
mewts  on  the  tops  of  screens,  minia- 
ture buttresns  for  ornament  instead 
of  strength,  miniature  sptrM,  and 
miniature  blank  windovra  in  orna- 
mental panelling. 

Pediments  are  generally  placed 
only  over  the  windows  of  the 
principal  floor  of  a  building,  to 
which  they  serve  to  give  distinc- 
tion and  importance.  Window 
pediments  are  either  angular  or 
curved  (t.  e.  segmental),  and  both 
forms  are  frequently  introduced 
.together,  and  placed  alternately, 


PBD 


PENTELIC  MARBLE. 


PEN 


in  which  case  it  is  usual  to 
place  an  angular  pediment  over 
the  centre  window.  Sometimes 
the  centre  window  alone  is,  for  the 
sake  of  distinction,  crowned  with  a 
pediment.  When,  as  is  generally 
the  practice,  all  the  pediments  to 
a  series  of  windows  are  alike,  they 
are  almost  invariably  made  angular 
ones,  although  there  are  instances 
of  the  contrary,  one  of  them  being 
Bridgewater  House,  where  Mr. 
Barry  has  given  segmental  pedi- 
ments to  all  the  windows  of  the 
principal  floor,  and  has  even  put 
them  over  the  centre  openings  of 
the  triple  windows;  and  it  de- 
serves to  be  further  remarked,  that 
he  has  enriched  their  tympanums 
vrith  sculptured  ornament — a  de- 
gree of  decoration  very  rarely  in- 
dulged in.  A  far  more  remarkable 
instance — ^perhaps  an  unique  one — 
of  the  application  of  segmental  pe- 
diments, may  be  seen  in  the  house 
just  erected  for  Mr.  Hope,  in  Pic- 
cadilly, large  pediments  of  that 
form  being  there  placed  over  win- 
dows consisting  of  two  openings, 
consequently  forming  square,  or 
nearly  square,  instead  of  upright 
compositions ;  owing  to  which,  the 
pediments  cause  them  to  look  far 
more  heavy  than  elegant.  In  that 
instance,  too,  the  pediments  are 
filled  in  with  sculpture;  the  figures, 
however,  are  not  exactly  confined 
to  the  pediments,  but  come  some- 
what lower  down,  the  horizontal 
cornice  being  partly  suppressed  for 
that  purpose. 

Pedometer,  in  mechanics,  an  instru- 
ment in  the  form  of  a  watch,  con- 
sisting of  various  wheels,  with  the 
teeth  catching  in  each  other,  and 
which,  by  means  of  a  string  fastened 
to  any  thing  in  motion,  numbers  the 
paces  gone  over  from  one  place  to 
another 

Peekf  in  navigation,  a  name  given  to 
the  upper  comers  of  sails  extended 
by  a  gt^i  or  by  a  yard  crossing  the 
mast  obUquely,  as  the  mizen-yard 
of  a  ship.    The  upper  extremity  of 

331 


those  gaffs  and  yards  is  also  called 
the  peek.  To  '  peek  the  mizen'  is 
to  put  the  mizen-yard  perpendicular 
to  the  mast. 

Peek'hahfordM,  the  ropes  or  tackles 
by  which  the  outer  end  of  the  gaff 
is  hoisted 

Peg-tankard^  an  ancient  species  of 
wassail-bowl,  used  in  the  time  of 
Queen  Elizabeth.  Itheldtwoquarts, 
and  had  generally  a  row  of  seven 
pegs,  dividing  the  height  into  eight 
equal  parts,  each  containing  half 
a  pint. 

Pendant,  an  ornament  suspended  from 
the  roof  of  a  Gothic  or  Tudor  build- 
ing; the  hanging  pendants  of  a 
vaulted  ceiling,  uniting  solidity  with 
ornament.  The  most  remarkable 
are  those  in  King  Henry  the 
Seventh's  chapel  at  Westminster 
abbey. 

Pendentwe,  the  portion  of  a  groined 
ceiling  supported  and  bounded  by 
the  apex  of  the  longitudinal  and 
transverse  vaults.  In  Gothic  ceil- 
ings of  this  kind  the  ribs  of  the 
vaults  descend  from  the  apex  to. 
the  impost  of  each  pendentive, 
where  they  become  united. 

Pennyweight,  the  20th  part  of  an 
ounce 

Pentagon,  a  figure  of  five  angles  and 
five  sides :  when  these  are  equal,  it 
is  called  a  regular  pentagon,  but 
otherwise,  it  is  irregular 

Pentagraph,  an  instrument  whereby 
designs,  prints,  &c  may  be  copied, 
in  any  proportion,  without  a  person 
being  skilled  in  drawing.  (See 
Pantogrt^h.) 

Pentangular,  in  geometry,  five-cor- 
nered or  angled 

Pentastgle,  in  architecturei  a  work  in 
which  there  are  five  rows  of  co- 
lumns 

PenteUe  marble,  in  statuary,  a  beau- 
tiful and  glossy  variety  of  Parian 
and  Carrara  marble,  named  from 
Mount  Pentelicus,  near  Athens, 
where  it  was  quarried.  Penteliic 
marble,  from  the  smallness  of  the 
grain,  is  mistaken  for  the  Parian ; 
but,  of  the  two,  the  former  is  of  a 


PEN 


PERICLES. 


PER 


finer  quality.  The  Pentelic  quar- 
ries duplay  in  a  remarkable  man- 
ner the  energies  of  the  ancient 
Athenians  :  whole  sides  of  the 
mountain  have  disappeared,  and 
present  uniformly  cut  perpendicular 
cliffs ;  and  holes,  still  to  be  traced 
on  the  slope  of  the  quarries,  made 
for  the  insertion  of  capstans,  mark 
the  place  of  the  mechanical  de- 
scent of  the  marble ;  whUst  a  da- 
maged and  rejected  cylinder,  appa- 
rently intended  for  a  part  of  a 
column  of  the  Parthenon,  interests 
the  traveller  on  the  ascent. 

Penthotuei  ^  projection  over  a  door, 
an  entrance,  a  window,  or  a  flight 
of  steps,  &c.,  for  protection  fi^m 
weather 

Peperino  marble,  in  mineralogy,  a 
calcareous  stone,  something  of  the 
nature  of  travertino.  It  is  supposed 
to  be  the  ancient  Saawn  Alianum, 
of  which  the  foundations  of  the 
capitol  at  Rome  (still  to  be  seen) 
were  built. 

Perambulator,  in  surveying,  an  in- 
strument for  measuring  distances ; 
named  also  the  Pedometer  and^S^- 
veying  wheel 

Perch,  a  small  projecting  beam,  cor- 
bel, or  bracket,  near  the  altar  of  a 
church 

Perch,  or  Pole,  a  linear  measure  of 
5^  yards 

Perclose,  an  enclosure,  a  railing ; 
sometimes  used  to  protect  a  tomb, 
or  to  separate  a  chapel  from  the 
main  body  of  the  church 

Percussion,  in  mechanics,  the  striking 
of  one  body  against  another,  or  the 
shock  arising  from  the  collision  of 
two  bodies 

Periacti,  the  revolving  scenes  of  the 
theatre,  called  scena  versatiUs  by 
the  Romans :  they  were  placed  be- 
fore the  itinera  versurartan,  or 
those  entrances  to  the  stage  which 
were  in  the  returns  of  the  perma- 
nent scene 

Periactos,  a  theatrical  machine,  con- 
sisting  of  three  scenes  placed  in 
the  form  of  a  triangle  on  a  revolv- 
ing platform;  so  that,  by  simply 

'      332       '  ~" 


turning  the  machine,    the   scene 
could  be  changed 

Pericles,  at  Ati^ens,  executed  the 
famous  statue  of  Minerva,  of  gold 
and  ivory.  Pausanias  says,  it  was 
standing  erect,  her  garments  reach- 
ing to  her  feet ;  she  had  a  helmet 
on,  and  a  Medusa's  head ;  in  one 
hand  she  held  a  spear,  and  on  the 
other  stood  a  Victory,  of  4  cubits 
high.  PUny  tells  us  the  statue 
was  26  cubits  high  (37  ft.  8  in.),  in 
which  he  perhaps  included  the 
pedestal,  whereon  they  both  say 
the  birth  of  Pandora  was  repre- 
sented. We  are  not  told  whether 
the  ivory  was  painted;  but  by  what 
Strabo  says,  that  Panaenus,  the 
brother  or  nephew  of  Phidias,  as- 
sisted him  in  colouring  the  statue 
of  Jupiter  at  Elis,  which  was  like- 
wise of  ivory  and  gold,  it  probably 
was.  The  reason  why  ivory  vras 
used  in  statues  of  this  kind,  ra- 
ther than  wood,  seems  not  to  have 
been  on  account  of  its  colour,  but 
because  wood  is  apt  to  crack,  and 
to  be  destroyed  by  worms:  but 
ivory  is  not  of  uniform  colour, 
being  yellow  near  the  outside  of  the 
tooth,  and  white  in  the  middle ;  it 
therefore  would  require  painting  on 
that  account,  and  likewise  to  hide 
the  joining  of  the  pieces.  Thncy- 
dides  says  the  gold  about  it  weighed 
40  talents,  which,  according  to  the 
value  of  gold  at  that  time,  was 
worth  about  £120,000  sterling. 

Pendromnu,  in  ancient  architecture, 
the  space  of  an  aisle  in  a  peripteron, 
between  the  columns  and  the  wall, 
used  for  walks  by  the  Greeks 

Perimeter,  the  boundary  of  any  figure, 
beiug  the  sum  of  all  the  sides  in 
right>hned  figures,  the  same  as  cir- 
cumference or  periphery  in  those  of 
a  circular  form 

Periphery,  the  drcumferenoe  of  a 
circle  or  ellipse 

Pery^teral,  a  temple  which  had  its 
cella  surrounded  by  columns 

PeristyHum,  a  continued  row  or  series 
of  rows  of  columns  all  roimd  a 
court  or  building,  in  contradistinc- 


PER 


PERPENDICULAR  STYLE. 


PHA 


tion  to  porticoes,  in  irhich  the 
pillars  did  not  surround  a  space, 
but  were  arranged  in  one  or  more 
parallel  lines 

Peritrochium,  in  mechanics,  a  wheel 
or  circle  concentric  with  the  base 
of  a  cylinder,  and  moveable  toge- 
ther with  it  about  an  axis :  the  axis, 
with  the  wheel  and  levers  fixed  in 
it,  to  move  it,  constitute  that  me- 
chanical power  called  axis  in  pen- 
troehio 

Perpendieuiar,  in  geometry,  a  line 
crossing  or  cutting  the  horizon,  or 
another  line,  at  right  angles 

Perpendieulart  formed  of  one  line 
meeting  another,  so  as  to  make 
the  angles  on  each  side  of  it  equal 
to  each  other 

Perpendicular  Style  of  Gothic  Jrchi- 
lecture,  derived  from  the  Decora- 
tive about  the  end  of  the  fourteenth 
century,  and  continued  till  the 
middle  of  the  sixteenth :  it  is  so 
called  from  its  tracery  consisting 
of  perpendicular  lines,  and  forming 
one  of  its  most  striking  features. 
Many  fine  examples  yet  exist  in 
England.  The  perpendicular  char 
racter  of  the  style  is  exhibited  in 
the  window  tracery,  where  the 
transoms  cross  the  mullions  at  right 
angles ;  and  in  large  windows  these 
are  occasionidly  repeated  several 
times :  bands,  quatr^oils,  and  other 
ornaments  are  more  frequently 
employed  than  in  the  other  styles, 
and  are  often  carried  across  the 
panellings  and  vertical  lines,  cre- 
ating a  rectilinear  arrangement, 
pervading  most  of  the  subordinate 
parta,  that  gives  a  peculiar  air  and 
stiffness.  Panelling  is  used  most 
abundantly  on  walls,  both  inter- 
nally and  externally,  and  also  on 
vaulting.  Some  fine  examples  of 
this  style  are  dravm  in  Mr«  Parker's 
'  Glossary,'  in  2  vols. 

Perpentstonef  a  bond-stone ;  a  large 
stone  reaching  through  a  wall  so 
that  it  appears  on  both  sides  of  it 

Perpetual  motum  is  that  which  pos- 
sesses within  itself  the  principle  of 
motion 


Perron,  in  architecture,  a  staircase 
outside  of  a  building,  or  the  steps 
in  frDnt  of  a  building  leading  up  to 
the  first  story 

Persian  Wheel,  a  name  given  to  a 
machine  for  raising  water,  which 
may  be  turned  by  means  of  a 
stream  acting  on  and  turning 
round  the  wheeL  The  buckets, 
instead  of  being  firmly  fastened, 
are  hung  upon  the  wheel  by  strong 
pins,  fixed  in  the  side  of  the  rim, 
which  must  be  made  as  high  as 
the  water  is  intended  to  be  raised 
above  the  level  of  that  part  of  the 
stream  in  which  the  wheel  is 
placed. 

Persians,  in  ancient  architecture, 
male  figures  employed  to  support 
entablatures;  the  female  figures 
were  named  Caryatides 

Perspective,  in  painting,  &c.,  the 
science  by  which  all  things  are 
ranged  on  a  plane  surface,  as  in  a 
picture,  according  to  their  appear- 
ance  in  their  real  situation 

Pew,  an  enclosed  seat  in  a  church,  in- 
troduced  since  the  Reformation. 
Previous  to  the  Reformation  the 
nave  was  occupied  by  the  congre- 
gation. Pews  are  fixed  seats,  se- 
parated from  each  other  by  wains- 
coting, and  varying  in  height. 

Pewter,  in  metallurgy,  a  mixed  metal, 
consisting  of  tin  variously  alloyed 
with  lead,  zinc,  bismuth,  or  anti- 
mony. Common  low-priced  pewter 
contains  20  parts  tin,  3  lead,  1  brass; 
best  pewter,  17  parts  antimony, 
100  parts  tin,  and  a  little  copper. 
Pewter  dishes  and  wooden  tren- 
chers were  the  ordinary  services 
of  our  ancestors  till  the  time  of 
Elizabeth,  when  "by  reason  of 
sharpe  lawsprovided  in  that  behalf," 
pewter  was  compounded  of  purer 
metal  than  before.  The  splendid 
services  of  gold  and  silver  were 
only  used  on  occasions  of  ceremony 
and  on  festivals. 

Pharos  or  Pharus,  a  lighthouse.  The 
most  celebrated  lighthouse  of  an- 
tiquity was  that  situat-ed  at  the 
entrance  of  the  port  of  Alexandria, 


333  p  5 


PHI 


PILES. 


PIL 


built  by  Sostratus  on  an  island, 
by  the  direction  of  Ptolemy,  at  a 
cost  of  800  talents.  Pliny  mentions 
the  lighthouses  of  Ostia  and  Ra- 
venna. The  name  of  Pharos  was 
given  in  allusion  to  that  of  Alex- 
andria, which  was  the  model  for 
their  construction. 

Phidiast  the  great  Greek  scnlptor  and 
director  of  the  works  under  Pericles 

PhonUxt  the  doctrine  of  sounds, 
otherwise  named  acoustics 

Phosphate  of  iron  is  a  native  ochre, 
which  classes  in  colour  with  the 
deeper  hues  of  ultramarine  ashes, 
and  is  eligible  for  all  their  uses. 
(See  Blue  ochre,)  Slate-clays  and 
several  native  earths  class  with 
grays;  but  the  colours  of  some  of 
the  latter,  which  have  been  tried, 
are  not  durable,  being  subject  to 
become  brown  by  the  oxidation  of 
the  iron  they  contain. 

Phy8ie$y  the  doctrine  of  natural 
bodies,  their  phenomena,  causes, 
and  effects,  with  their  various  mo- 
tions, operations,  affections,  &c. 
Taken  in  its  most  enlarged  sense, 
it  comprehends  the  whole  study 
of  Nature,  and  includes  physiology 
and  natural  history. 

Piazza^  an  open  area  or  square;  a 
covered  walk  or  portico 

Pickf  an  instrument  in  common  use 
as  well  in  agricultural  as  in  mining 
operations 

Pictura  (Latin),  a  painting.  The  art 
of  imitating  the  appearances  of 
bodies  upon  an  even  surface,  by 
means  of  light  and  shade,  or  co- 
lour, was  most  extensively  cul- 
tivated by  the  ancients,  but  es- 
pecially  by  the  Greeks,  amongst 
whom  it  was  carried  to  the  high- 
est degree  of  technical  develop- 
ment. 

PfffT,  in  architecture,  the  strong 
columns  on  which  the  arch  of  a 
bridge  is  raised 

PieTt  the  solid  mass  between  doors, 
windows,  and  other  openings  in 
buildings:  the  term  is  often  ap- 
plied  to  pillars  in  Norman  and 
Gothic  architecture 

334  "" 


PierSf  walls  built  to  support  arches, 
and  from  which,  as  bases,  they 
spring 

PikB,  square  blocks  placed  upon  the 
epistylia,  and  immediately  over  the 
columns  in  a  basilica,  for  supporting 
the  timbers  of  the  roof.  Hlse  were 
also  buttresses  built  against  the 
walls  of  a  mole,  to  resist  the  force 
of  the  waters. 

Piloitert  in  architecture,  a  square 
column,  sometimes  insulated,  but 
m<Hre  frequently  set  within  a  wall, 
and  only  showing  a  fourth  or  fifth 
part  of  the  thickness.  Pilasters 
were  unknown  in  Greek  archi- 
tecture, in  which  only  antss  (see 
Anta)  were  admitted :  they  are 
employed  by  the  modems  as  sub- 
stitut<»  fw  an  order  in  engaged 
columns,  and  are,  perhaps,  even 
preferable  to  the  latter,  inasmuch 
as  they  combine  better  and  more 
naturally  with  the  wall  to  which 
they  are  attached. 

Piles,  as  applied  in  engineering  ope- 
rations, are  used  both  in  temporary 
and  in  permanent  constructions. 
In  the  former  cases,  they  are  com- 
monly squared  logs  or  baulks  of 
timber,  which  are  driven  close  to- 
gether in  single  or  double  rows,  so 
as  to  enclose  a  space  of  water,  and 
form  a  coffer-dam,  from  which  the 
water  is  subsequently  pumped  out, 
and  thas  a  dry  space  obtained  for 
laying  the  foundations  of  piers, 
abutments,  &c.  in  bridges  and  other 
similar  works.  The  most  substan- 
tial kind  of  coffer-dam,  adapted  for 
works  which  will  be  long  in  con- 
struction, is  formed  of  a  double  row 
of  concentric  piling,  a  space  of  3  or 
more  feet  being  left  between  the 
two  rows  of  piles,  which  is  filled 
with  clay,  well  puddled  or  rammed 
in.  For  permanent  woriu,  piles 
are  driven  in  loose  or  uncertain 
strata  in  rows,  leaving  a  space  a 
few  feet  in  width  between  them, 
and  upon  the  heads  of  the  piles  the 
foundations  of  the  superstructure 
are  erected.  In  some  of  the  iron 
bridges  lately  erected  for  railways, 


PIL 


PILING. 


PIL 


piles  have  been  nsed  as  substitutes 
for  solid  piers  in  the  water.  Wharf, 
walls  have  also  been  built  with 
facings  formed  with  piles.  In  most 
of  these  works  the  piles  used  are 
of  cast  iron,  while  those  used  for 
coffer-dams  and  foundations  are  of 
timber,  the  lower  end  being  fitted 
with  a  wrought-iron  pointed  shoe, 
to  facilitate  the  penetration  of  the 
strata,,  and  the  head  of  the  pile 
guarded  with  a  ring  of  the  same 
metal,  to  prevent  its  splitting  while 
being  driven.  Iron  piles  are  cast 
in  various  form^ ;  sometimes  so  as 
to  preserve  similar  external  dimen- 
sions to  timber  piles,  and  hollow  or 
tubular  within ;  and  if  for  wharf- 
walls,  they  are  formed  with  grooves 
in  the  sides,  into  which  metid  plates 
are  fitted,  the  piles  being  placed 
from  4  to  7  feet  apart,  and  the  in- 
termediate spaces  filled  up  with 
these  plates. 

For  piling  in  loose  and  moveable 
materials,  and  more  especially  for 
forming  moorings,  Mr.  Mitchell  has 
introduced  a  form  of  pile  which  is 
properly  called  a  acrew-pile,  the 
lower  end  being  formed  as  a  screw, 
and  fitted  (for  moorings)  with  a 
broad  plate  or  disc  of  metal  in  a 
spiral  or  helical  form.  The  most 
important  purpose  to  which  the 
screw-pile  has  been  applied  is  for 
forming  the  foundations  of  light- 
houses, beacons,  jetties,  &c.,  in 
places  where  the  sand  or  soil  is  too 
unstable  to  bear  thb  weight  of  any 
massive  structure,  or  where  the 
force  of  the  waves  would  endanger 
masses  of  masonry  by  undermining 
the  materials  below  them.  The 
lighthouse  erected  in  the  year  1840 
upon  the  Maplin  Sands  may  be  in- 
stanced as  a  work  which  owes  the 
very  possibility  of  its  existence  to 
these  screw-pile  foundations.  The 
piles  used  in  this  structure  are  nine 
in  number,  and  made  of  malleable 
iron,  5  inches  in  diameter  and  26 
feet  long,  with  a  cast-iron  screw 
4  feet  in  diameter,  screwed  to  the 
foot  of  each.    Eight  of  the  piles 

33& 


were  placed  at  the  angles  of  an 
octagon,  and  the  ninth  in  the  cen- 
tre, and  were  put  down  in  nine 
consecutive  days,  being. screwed  to 
a  depth  of  22  feet  in  the  bank. 
Several  similar  works  have  been 
since  constructed  with  complete 
success ;  and  in  1847,  the  screw- 
piles  were  applied  in  the  construc- 
tion of  a  jetty  260  feet  in  length 
beyond  the  old  one,  at  Conrtown, 
on  the  coast  of  Wexford.  Mallea- 
ble-iron piles,  5  inches  in  diameter, 
and  laid  in  the  ground  11  to  15 
feet,  were  fitted  with  screws  2  feet 
in  diameter.  The  facility  and  ra- 
pidity with  which  these  piles  are 
inserted  are  not  the  least  among 
their  qualifications. 

Before  the  introduction  of  screw- 
piles, — the  process  of  fixing  which 
consists  in  giving  them  a  rotatory 
motion  by  means  of  capstans, — ^the 
fixing  of  piles  was  accomplished  by 
driving  them  downwards  by  the 
force  of  an  adequate  weight,  which 
was  permitted  to  fall  vertically  on 
them  from  a  considerable  height. 
The  nuichinery  employed  vras  there- 
fore properly  called  a  pik'drweri 
and  consisted  simply  of  a  vertical 
framing,  provided  with  winches  and 
chains,  by  which  the  weight  or 
'  monkey'  was  alternately  raised  by 
manual  power,  and  released  so  as 
to  fall  upon  the  head  of  the  pile ; 
or  a  gin  was  applied,  and  horses 
used  for  the  same  purpose. 

Within  the  last  few  years  a  great 
improvement  has  been  effected  in 
the  machinery  for  pile-driving,  by 
the  application  of  steam  power. 
The  earliest  invention  for  this  pur- 
pose is  recorded  in  a  patent  granted 
in  1806,  but  no  practical  applica- 
tion appears  to  have  resulted  for 
many  years.  The  patent  referred 
to  was  dated  June  6,  1806,  and 
granted  to  William  Deverell,  for 
"improvements  in  the  mode  of 
giving  motion  to  hammers,  stamp- 
ers, knives,  shears,  and  other  things, 
without  the  application  of  wheels, 
pinions,  or  any  rotative  motion,  by 


PIL 


PILES,  MR.  POTTS'. 


PIL 


meaiu  of  .Tarious  powers  now  in 
common  use."  The  apparatus  was 
designed  to  consist  of  a  steam- 
cylinder  with  piston  and  rod,  and 
a  hammer,  raised  by  admitting  the 
steam  below  the  piston.  By  the 
condensation  or  the  escape  of  the 
steam,  the  hammer  and  the  piston 
were  allowed  to .  descend,  urged 
both  by  their  own  weight  and  by 
the  elasticity  of  the  compressed  air 
in  the  top  of  the  cylinder  above  the 
piston.  This,  therefore,  established 
theprineiple  of  the  steam-hammer; 
but  the  most  successful  application 
of  it  to  the  purposes  of  driving 
piles,  as  well  as  to  those  of  the 
smithery,  is  due  to  Mr.  James 
Nasmyth,  whose  steam-hammer 
consists  of  a  steam-cylinder,  which 
is  closed  at  the  bottom,  but  has 
openings  in  the  top,  to  admit  the 
passage  of  air.  The  rod  of  the 
piston  passes  through  a  steam-tight 
aperture  in  the  bottom  of  the  cy- 
linder, and  has  the '  monkey,'  or 
driver,  weighing  2|  tons,  suspended 
from  it.  The  machine  is  worked 
with  high-pressure  steam,  which, 
entering  the  bottom  of  the  cylinder, 
raises  the  piston  and  'monkey.' 
When  the  piston  reaches  the  height 
intended,  it  shuts  the  induction 
and  opens  the  eduction  pipe  (also 
at  the  bottom  of  the  cylinder),  by 
which  the  steam  escapes,  and  the 
monkey  falls.  A  heavy  iron  cap 
slides  between  standards  and  round 
the  head  of  the  pile,  and  thus  guides 
it  in  its  descent.  This  machine,  as 
used  at  Devonport,  in  driving  piles 
for  the  steam-dock,  made  seventy 
strokes  per  minute,  and  drove  piles 
14  inches  square  and  18  feet  in 
length. 

In  the  year  1843  (December  5), 
a  patent  was  obtained  by  Dr.  L.  H. 
Potts,  for  "improvements  in  the 
constcuction  of  piers,  embankments, 
breakwaters,  and  other  similar 
strifGl^ures."  The  several  objects 
coi^pfise4  in  this  invention  were 
sought  with  considerable  ingenuity, 
and  have  been  realized  with  suc- 

336  ~ 


cess.  The  invention  includes  the 
application  of  hollow  piles  of  iron, 
of  a  cylindrical  or  other  convenient 
form,  and  sinking  them  by  with- 
drawing the  sand,  &c.  within  them 
by  the  action  of  an  air-pump.  For 
this  purpose  the  pile  is  fitted  with 
an  air-tight  lid,  through  which  a 
pipe  passes  to  connect  the  interior 
of  the  pUe  with  a  receiver.  The 
receiver  is  connected  by  a  pipe 
with  a  three-barrelled  air-pump,  by 
working  which  the  air  is  exhausted 
from  the  hollow  pile,  and  the  sand 
and  water  raised  into  the  receiver, 
which  is  emptied  as  often  as  neces- 
sary. A  second  purpose  proposed 
in  this  patent  is  the  use  of  skeleton 
frames  or  cases  of  cast  iron  in  con- 
nection with  the  pUes,  for  securing 
them  together,  and  preserving  their 
relative  positions.  A  third  object 
is  the  injection,  by  hydraulic  press- 
ure, of  such  chemical  solutions 
about  the  feet  of  the  piles  as  will 
consolidate  the  sand  upon  which 
they  stand,  and  thus  secure  the 
work.  And  the  inventor  also  pro- 
posed to  use  hydraulic  cements  in 
a  dry  state,  delivered  at  the  base  of 
the  piles,  by  the  admixture  of  which 
cements  with  the  water  they  would 
become  solidified,  and  thus  materi- 
ally aid  in  strengthening  the  super- 
structure. 

Recently  these  piles  have  been 
successfully  used  on  the  Goodwin 
Sands,  by  the  Trinity  Board.  Pre- 
viously, engineers  had  been  bafiled 
in  finding  a  bottom.  The  piles  have 
now  been  fairly  afSxed  to  the  hard 
bottom,  seventy-five  feet  through 
the  sand. 

In  connection  with  Mitchell's, 
Nasmyth's,  and  Potts'  modes  of 
piling,  it  is  proper  to  notice  also 
Cram's  patent  pUe-driving  locomo- 
tive machine,  which  was  successful 
in  its  operation  in  the  United  States. 
The  volume  ('  Ensamples  of  Rail- 
way-Making') from  which  the  fol- 
lowing extract  has  been  made  was 
edited  by  the  publisher  of  this 
Dictionary,  with  a  view  to  induce  a 


\  PIL. 


PILB-ROAD. 


PIL 


cheaper  mode  of  construction  of 
railways  in  countries  less  wealthy 
than  those  already  intersected  by 
iron  roads : 

J^ile'Toad. — As  a  considerable 
length  of  the  Utica  and  Syracuse 
raibnoad   passes   through    a   deep 
swamp,  a  foundation  of  great  per- 
manency was  required:  this  gave 
riae  to  a  modification  of  the  super- 
atracture,  and  formed  that  which 
is  known  as  pile-road.  The  swamp 
varied  in  depth  from  10  feet  to  60 
feet,  and  was  nearly  on  a  dead  level 
throughout :  the  grade-line  closely 
corresponded  with  its  surface;  so 
that  it  was  necessary  to  reach  the 
hard  bottom  before  any  foundation 
could    be    effected.     Piles   were 
adopted  as  the  cheapest  and  most 
efficacious  means  to  secure  a  dura- 
ble  and  substantial    basis :    they 
were  driven  to  their  places  by  a 
steam  pile-driver.    This  was  a  ma- 
chine formed  of  a  platform  about 
25  feet  long  and  8  feet  broad :  at 
one  end  were  eiected  two  pairs  of 
leaders  or  guides,  in  which  the 
hammers  moved.  Immediately  be- 
hind the  leaders  were  fixed  the 
rollers,  with  the  necessary  brakes 
and  gearing  for  working  the  ham- 
mersy  raising  the  piles,  &c.    The 
rollers  were  revolved  by  a  small 
high-pressure  steam  engine,  occu- 
pying the  rear  of  the  machine.  The 
arrangement  of  the  leaders  was  the 
same  as  in  ordinary  piling  machines: 
a  curved  piece  of  wood  forced  open 
the    sheers    when   the    hammers 
reached  their  elevation.  The  ham- 
mers were  confined  to  the  leaders 
by  a  groove :  they  weighed  about 
1000  lbs.  each,  were  made  of  cast 
iron,  and  at  their  last  blow  fidb 
through  a  space  of  27  feet.   A  pair 
of  piles  were  driven  at  one  opera- 
tion by  this  machine ;  when  driven, 
cast-iron  rollers  were  placed  upon 
their  heads,  and  the  machine,  by 
means  of  an  inverted  rail,  moved 
on  to  the  next  place.    The  heads 
of  the  piles,  sawed  off  to  reduce 
them  to  the  proper  level,   were 

^37 


found  sufiicient  to  supply  the  fur- 
nace  with  fuel. 

The  men  employed  in  operating 
the  machine  were, — a  foreman,  a 
steam  engineer,  two  brake-men,  and 
two  men  in  front  at  the  saws ;  also 
a  horse  and  cart,  to  furnish  water 
for  the  boUer.  Properly  geared  in 
front  of  the  machine,  and  between 
the  leaders,  was  a  saw  that  played 
on  a  sway-bar  and  could  be  pressed 
against  either  pile  as  it  was  driven 
home.  The  machine  was  manu- 
factured complete  for  the  cost  of 
£400. 

Each  pile  was  prepared  for  being 
driven  by  simply  sharpening  one 
end  to  a  point,  and  squarely  butt- 
ing the  other ;  it  was  drawn  up  by 
ropes  woriied  by  the  engine,  se- 
cured in  position  between  the 
leaders,  and  driven  to  the  hard 
bottom.  Generally  the  piles  mani- 
fested no  disposition  to  split :  when 
they  did,  their  heads  were  encom- 
passed with  an  iron  hoop.  When 
the  pUe  was  not  of  sufficient  length 
to  reach  the  hard  bottom,  another 
was  dowelled  upon  its  head,  and 
this  was  repeated  as  often  as  ne- 
cessary. The  piles  were  charred, 
to  increase  their  durability ;  and  an 
auger-hole,  bored  in  their  heads  for 
the  purpose,  was  filled  with  salt, 
and  securely  plugged  up. 

Pillar,  a  kind  of  irregular  column, 
round  and  insulate,  but  deviating 
from  the  proportion  of  a  just 
column.  The  term  pillar  is 
more  usually  applied  to  Gothic 
architecture  than  to  the  Classical, 
the  latter  being  governed  by  the 
rules  of  proportion :  not  so  with 
the  Gothic  pillar,  it  being  subject 
to  no  fixed  rules. 

Pillars  (numumental),  columns  raised 
for  the  commemoration  of  events, 
a  practice  from  remote  antiquity. 
"  Jacob  set  a  pUlar  upon  her  grave : 
that  is  the  pillar  of  Rachel's  grave 
unto  this  day."  (Gen,  xxxv.  20.) 

Pillars,  in  ship-building,  pieces  Qxed 
under  the  middle  of  the  beams,  to 
support  the  decks 


PIL 


PISE. 


PIS 


Pillion,  the  tin  that  remains  in  the 
slags  after  it  is  first  melted. 

Pinaeotheea,  a  picture  gallery.  The 
public  gallery  at  Mnnich  is  called 
the  Pinakothek, 

Pindrill,  a  drill  used  for  catting  a 
recess  for  a  bolt-head,  or  for  en- 
larging a  hole 

Pines  and  Firs  are  cone -bearing 
timber-trees  which  thrive  best  in 
cold  climates:  they  are  of  great 
variety,  and  the  general  uses  of 
the  wood  are  innumerable,  besides 
those  for  ships  and  house  car- 
pentry. Its  use  in  England  is 
most  extensive:  it  is  principally 
imported  from  America,  Norway, 
the  Baltic,  Memel,  Riga,  Dantzic, 
&c. 

Pinion,  in  mechanics,  an  arbour  or 
spindle,  in  the  body  of  which  are 
several  notches,  into  which  the 
teeth  of  a  wheel  catch,  that  serves 
to  turn  it  round;  it  is  also  the 
name  of  a  lesser  wheel  that  plays 
in  the  teeth  of  a  larger  one 

Pinite,  a  micaceous  mineral 

Pint,  in  navigation,  a  name  given  to 
a  ship  with  a  very  narrow  stem 

Phmaele,  an  ornament  placed  on  the 
top  of  a  buttress  as  a  termination 
to  an  angle  or  gable  of  a  house, 
church,  or  tower;  also  a  summit 
or  lofty  apex 

Pi$t8,  in  ships,  are  fixed  in  the  drum- 
h«ids  of  capstans,  through  the 
ends  of  the  bars,  to  prevent  their 
unshipping;  sometimes  put  through 
the  bolts  to  belay  a  rope,  and 
called  belaying  pins;  and  some- 
times the  main  bolts  are  called 
bolt-pins 

Pipe,  a  tube  for  the  conveyance  of 
water,  gas,  or  steam,  of  various 
dimensions  and  uses 

Ptj9«,  in  mining,  a  running  vein, 
having  a  rock  root  and  sole 

Piscina,  Pliny  says  the  Romans 
adorned  the  walls,  ceilings,  and 
floors  of  their  baths.  It  was  on 
the  piscina  they  bestowed  the  most 
axt.  In  the  baptisterium  they 
dipped  their  whole  body,  and  this 
was  large  enough  to  swim  in ;  but 

338 


when  they  were  disposed  to  swim  at 
large  in  warmer  water,  they  en- 
tered the  piscina,  a  basin  so  <»lled, 
as  its  size  bore  some  resemblance 
to  a  pond.  When  the  thermae  were 
built,  they  were  n^ade  to  contain 
lakes  of  warm  water:  the  water  ac- 
quired its  heat  by  passing  through 
the  fire  in  a  brass  pipe,  and 
must  have  been  more  or  less  hot 
according  to  the  tength  of  its  pro- 
gress. 

Piscina,  a  shallow  stone  basin,  or 
trough,  with  a  hole  in  the  bottom, 
formerly  placed  near  to  the  altar 
in  Roman  Catholic  churches,  and 
fixed  at  a  convenient  height  above 
the  floor,  to  hold  the  water  in  which 
the  priest  washed  his  hands;  also  for 
rinsing  the  chalice  at  the  time  of 
the  celebration  of  the  mass.  It  was 
usually  on  the  right-hand  side,  on 
the  approach  to  the  altar. 

Pis/,  a  peculiar  mode  of  forming 
buildings,  particularly  those  for 
cottages  and  farming  purposes,  vrith 

'  some  sort  of  stiff  earthy  materials 
of  a  loamy  quality.  The  earth  so 
collected,  framed,  is  well  rammed 
until  the  moisture  is  driven  out,  and 
used  to  make  the  walls  or  sides  of 
the  building,  instead  of  bricks.  It 
has  been  used  with  much  economy 
and  success  on  the  Continent,  and 
in  some  parts  of  England. 

Pistiei,  or  Pasiiei,  a  term  by  which 
Italians  distinguish  pictures  which 
cannot  be  called  either  original  or 
copies,  being  the  works  oif  some 
artists  who  have  had  the  skill  to 
imitate  the  manner  of  design  and 
colouring  of  other  eminent  masters ; 
sometimes  borrowing  part  of  their 
pictures,  sometimes  imitating  their 
touch,  their  style  of  invention, 
their  colouring,  and  expression. 
Several  painters,  of  considerable 
reputation  for  their  own  original 
performance,  have  made  themselves 
remarkable  in  this  way ;  but  none 
of  them  more  than  David  Teniers, 
who  so  successfully  counterftited 
Giacopo  Bassan,  as  to  deceive  the 
most  judicious,  in  many  instances. 


PIT 


PLAIN  SAILING. 


PLA 


at  the  first  tight ;  though,  upon  a 
closer  inspection,  his  light  and  easy 
pencil,  and  a  predominant  gray 
tint,  which  is  observahle  in  the 
coloaring  of  that  master,  show  a 
perceptible  difference  between  his 
pencil  and  colouring,  when  they 
are  carefully  examined  and  com- 
pared with  Bassan's.  (See  Pas- 
tici,) 

PistoUf  a  moveable  air-tight  division 
within  the  steam-cylinder,  acted 
upon  by  the  steam.  Pistons  are 
either  metallic  or  packed.  Metallic 
pistons  usually  have  segments  of 
brass  or  cast  iron,  called  junk- 
rings,  pressed  outward  by  springs. 
Packed  pistons  are  surrounded  by 
well-greased  hemp. 

PUton-rodi  the  rod  fixed  to  the  piston, 
to  communicate  its  motion  to  the 
crank 

Pitchf  in  building,  the  vertical  angle 
of  a  roof,  or  the  proportion  between 
the  heights  and  spans,  as  when  the 
height  is  one-fourth,  one-third,  or 
one-half,  of  the  breadth  of  the 
buflding.  If  the  height  is  one-half 
of  the  breadth,  the  inclination  of 
the  planes,  forming  the  vertical 
angle,  is  a  right  angle. 

Pitchmg-pieee,  in  staircasmg,  a  ho- 
rizontal piece  of  timber  having  one 
of  its  ends  wedged  into  the  wall, 
at  the  top  of  a  flight  of  steps,  to 

'  support  the  upper  ends  of  the 
rough  strings 

Piteh-wheeL  When  two  toothed- 
wheels  work  together,  the  circles 
of  contact  are  called  the  propor- 
tional circles,  or  pitch  circles. 

Pit-4iumt  one  employed  to  look  after 
the  lift  of  pumps  and  the  drainage 

Pit'Work,  the  pumps  and  other  ap- 
paratus of  the  engine  shaft 

Pitfot,  a  stud  or  small  pin  on  which 
any  thing  turns 

PijPf  in  church  rituals,  a  little  chest 
or  box,  in  which  the  consecrated 
host  is  kept 

^^otfi  chartf  in  navigation,  is  a  sea- 
chart,  wherein  the  meridian  and 
parallels  are  straight  paralld  lines, 
as  in  Mercator's  projection;  con- 


sequently  the  degrees  of  longitude 
are  the  same  in  all  latitudes 

Plain  saUmfff  in  navigation,  the  art  of 
working  a  ship's  motion  on  a  plain 
chart,  which  supposes  the  earth  to 
be  an  extended  plane,  or  flat,  and 
not  globular 

Plan.  The  plan  of  a  building  may 
be  familiarly  described  as  an  ar- 
chitectural nugf;  therefore  only 
those  who  cannot  comprehend  a 
geographical  or  topographical  map 
can  be  at  any  loss  to  under- 
stand an  architectural  one,  the 
latter  being  precisely  of  the  same 
nature  as  the  others,  with  this  dif- 
ference in  its  favour,  that  it  is 
much  less  conventional.  To  define 
it  more  exactly, — a  plan  is  a  hori- 
zontal section  supposed  to  be  taken 
on  the  level  of  the  floor  through 
the  solid  parts  of  the  fabric — walls, 
columns,  &c.,  so  as  to  show  their 
various  thicknesses  and  situations, 
the  dimensions  of  the  several  spaces 
or  rooms,  the  position  of  the  doors 
by  which  they  communicate  with 
each  other,  and  various  particulars 
that  cannot  otherwise  be  explained. 
Studying  buildings  without  plans, 
is  like  studying  geography  without 
maps.  A  plan  frequently  costs 
the  arehitect  more  study  than  all 
the  rest  of  his  design,  and  much 
mistaken  are  those  who  suppose 
that  convenience  alone  has  chiefly 
to  be  considered.  Convenience  is, 
of  course,  or  ought  to  be,  made  a 
sine  qud  non  /  yet  it  is  not  so  much 
a  positive  merit  in  itself,  as  the 
want  of  it  is  a  positive  defect. 
Mere  convenience  is  not  an  artistic 
quality:  from  that  to  beauty  of 
plan, —  to  striking  combinations, 
and  studied  effects,  and  varied  play 
of  arrangement, — ^the  distance  is 
very  great.  A  common-place  plan 
is  but  a  very  dull,  uninteresting 
affui:  it  is  no  more  than  what 
any  builder  can  accomplish ;  but  a 
plan  rei^ete  with  imagination,  pi- 
quant play,  and  well-imagined  con- 
trasts, is  no  every-day  matter. 

Planceer,  the  soffit  or  under  side  of 


PLA 


PLANING  MACHINE. 


PLA 


the  corona  of  a  cornice,  in  Classical 
architectoTe 

PkaUf  in  smreying,  a  level  surface, 
parallel  to  the  horizon.  In  car- 
pentry, an  instrument  by  which 
the  surfaces  of  bodies  are  smoothed. 

Planet  inclined:  in  mechanics,  this 
resembles  one  half  of  a  wedge  that 
has  been  cut  in  two  parts  lengthwise 

PkoMy  in  geometry,  a  plain  level 
figure,  or  a  surface  lying  evenly 
within  its  boundary  lines 

Planing  Machine^  an  invention  for  di- 
minishing the  great  labour  of  plan- 
ing the  surfaces  of  planks  and 
boards  of  wood,  and  for  reducing 
the  surface  to  a  true  and  smooth 
&ce,  by  means  of  planes,  or  instru- 
ments of  a  similar  nature,  which 
are  actuated  by  the  power  of  the 
machinery  instead  of  the  strength 
of  a  man's  arm 

Planing  Machine,  The  invention 
of  the  *  slide  -  rest,'  which  has 
effected  such  an  important  im- 
provement in  cylindrical  andconical 
turning,  has  been  of  far  superior 
advantage  in  its  application  to  the 
planing  of  surfaces,  as  the  planing 
machine  is  but  the  slide-rest  ap- 
plied to  a  traversing  table^  In 
planing  machines  of  the  ordinary 
construction,  the  bed  or  basement 
frame  has  two  angular  ridges  from 
end  to  end,  one  on  each  side, 
which  fit  into  corresponding  angu- 
lar grooves  in  a  traversing  table. 
This  table  rests  upon  the  ridges, 
and  is  moved  backwards  and  for- 
wards  by  a  screw-rack  and  pinion, 
or  chain :  its  surface  is  accurately 
planed,  and  the  work  being  fast- 
ened upon  it  partakes  of  its  mo- 
tion, and  is  constrained  to  move  in 
a  perfectly  straight  line.  Over  the 
traversing  table,  at  the  centre  of 
the  machine,  is  fixed  a  slide-rest, 
which  is  held  fast  by  being  bolted 
to  two  upright  standards  fixed  to 
the  bed,  one  on  each  side.  The 
horizontal  slide  has  another  at 
right  angles  to  it,  which  serves  to 
hold  the  cutting  tool  and  adjust  it 
to  the  work,  so  as  to  take  a  cut 

340 


more  or  less  deep,  as  required.  To 
the  long  screw  of  the  horizontal 
slide  mechanism  is  connected, 
which  causes  it  to  advance  the 
vertical  slide  and  tool  a  very  small 
distance  across  the  machine,  just 
before  the  commencement  of  each 
forward  movement  of  the  table ;  so 
that  by  a  repeated  series  of  move- 
ments to  and  fro  of  the  table,  the 
tool  is  made  to  traverse  the  whole 
surface  of  the  work ;  and  thus,  by 
the  perfectly  level  movement  of  the 
table  in  the  one  direction,  and  that 
of  the  slide  in  the  other,  a  per- 
fectly plane  surface  is  obtained. 
In  some  machines  the  table  is 
made  to  travel  backward  at  a  much 
faster  rate  than  in  the  forward 
motion,  so  as  to  save  time ;  and  in 
others,  the  cutting  tool  acts  in 
both  movements,  by  being  turned 
at  the  end  of  each. 

Planishf  in  carpentry,  &c.,  to  smoothe, 
to  polish 

PlanisheTf  a  thin  flat-ended  tool,  used 
by  turners  for  smoothing  brass- 
work 

Planisphere^  in  geometry,  &c.,  a 
sphere' projected  on  a  plane ;  such 
are  maps  of  the  heavens  or  of  the 
earth 

Plankf  a  term  applied  to  all  super- 
ficial timber  which  is  4  inches  thick 
and  under,  except  1 -inch,  and  some- 
times H-inch,  which  come  under 
the  denomination  of  board 

Plank-eheerSj  in  ship-building,  pieces 
of  plank  laid  over  the  timber  heads 
on  the  quarter-deck,  forecastle,  and 
round-house 

Plane  -  trecj  a  native  of  Europe ;  it 
is  also  abundant  on  the  banks  of  the 
Mississippi  and  Ohio.  This,  per- 
haps one  of  the  largest  of  the 
American  trees,  is  sometimes  12 
feet  in  diameter,  and  is  much  used 
in  that  country  for  quays.  It  is 
used  here  for  musical  instruments, 
and  other  works  requiring  a  dean 
light-coloured  wood. 

Plasm,  in  the  arts,  a  mould ;  a  matrix 
in  which  any  thing  is  cast  or 
formed 


PLA 


PLATINUM, 


PLE 


Plaster  qf  Parity  in  mineralogy  and 
the  arts,  gypsam  deprived  of  its 
water  by  burning,  and  reduced  to 
a  white  powder,  which  is  afterwards 
mixed  with  water.  It  serves  many 
purposes  in  building,  and  is  used 
likewise  in  sculpture,  to  mould  and 
make  statues,  basso-relievos,  and 
other  decorations  in  architecture. 
It  is  dug  out  of  quarries  in  several 
parts  of  the  neighbourhood  of  Paris, 
whence  its  name.  The  finest  is 
that  of  Montmartre.  It  is  known 
also  as  gypsum. 

Piaaterinfff  the  art  of  covering  the 
walls  and  ceilings  of  a  house  or 
other  edifice  with  a  composition, 
of  which  the  groundwork  is  lime 
and  hair  mortar,  finished  with  a 
coating  of  finer  materials 

Plat,  in  mining,  ground  appropriated 
to  ore  or  deads 

Plat-band,  a  flat  fascia,  band, or  string, 
whose  proportion  is  less  than  its 
breadth;  the  lintel  of  a  door  or 
window  is  also  sometimes  so  named 

Plate,  and  other  services  for  the 
table.  In  the  time  of  Henry  VIII. 
and  Elizabeth,  amongst  the  nu- 
merous costly  and  magnificent  ar- 
ticles for  the  table,  wrought  in 
silver,  gold,  and  other  precious 
material,  were  chargers,  dishes, 
plates,  porringers,  saucers,  vases  or 
cups,  pots  or  tankards,  flagons, 
pitchers,  pottels,  ewers,  creuses, 
bowls,  goblets,  basins,  washing- 
basins  and  ewers,  horns,  cups  for 
caudle  cruets,  spice-plates,  spiceries, 
salt-cellars,  pepper-boxes,  spoons, 
and  candlesticks. 

Plate,  a  term  applied  to  horizontal 
timbers,  placed  on  walls,  &c.,  to 
receive  other  timber-work :  that  at 
the  top  of  a  building  immediately 
under  the  roof  is  a  wall-plate ;  those 
also  which  receive  the  ends  of  the 
joists  of  the  floors  above  the  ground 
floor  are  called  the  same 
Plate-bending  Machine.  Thisinvention 
was  contrived  for  bending  plates  of 
metal  into  any  required  curve,  and 
is  particularly  useful  in  the  con- 
gtruction  of  boilers  and  the  buckets 

341 


of  water-wheels :  it  consists  of  two 
side-frames,  which  carry  three  uron 
rollers  and  the  spur-wheels  and 
pinions  necessary  to  communicate 
motion  to  two  of  them,  one  of 
which  is  placed  immediately  over 
the  other,  and  can  be  raised  or 
lowered  by  screws  to  the  thickness 
of  the  plate  to  be  bent.  The  third 
roller  is  placed  behind  the  first 
two,  and  it  is  the  height  of  this 
roller,  with  respect  to  that  of  the 
other  two,  that  determines  the  de- 
gree of  curvature  of  the  plate :  it 
is  therefore  made  capable  of  ad- 
justment by  set-screws,  and  being 
placed  to  the  proper  height,  and 
the  machine  set  in  motion,  the 
plate  is  passed  between  the  first  two 
rollers,  till,  coming  in  contact  with 
the  third,  it  rises  upward  and  takes 
the  form  of  a  curve. 

Platina,  yellow,  is,  as  its  name  im- 
pUes,  a  preparation  from  platina, 
which  affords  a  series  of  yellow 
pigments,  the  deep  colours  of 
which  resemble  the  Terra  di 
Sienna,  but  are  warmer  in  tone  and 
richer  in  colour  and  transparency, 
much  resembling  fine  gall-stones, 
for  which  they  are  valuable  sub- 
stitutes. They  work  well,  and  are 
permanent  both  in  water  and  oU, 
when  carefully  prepared ;  but  any 
portion  of  palladium  in  the  metal 
from  which  they  are  prepared 
neutralizes  their  colour  and  renders 
them  useless. 

Platinum  is  found  in  the  metallic 
state  alloyed  with  other  metals, 
but  not  in  large  quantities.  It 
is  not  so  white  a  metal  as  silver, 
but  is  very  malleable  and  ductile, 
either  when  hot  or  cold.  No  fur- 
nace can  melt  it;  but  by  the  oxyhy- 
drogen  blow-pipe,  or  by  a  voltaic 
current,  it  is  capable  of  being  fused, 
and  may  be  dissipated  in  the  air. 
Alone  it  is  insoluble  in  nitric  acid, 
but  when  alloyed  with  other  metals 
it  is  soluble. 

Plenum,  in  physics,  a  term  used  to 
signify  that  state  in  which  every 
part  or  space  or  extension  is  sup- 


PLI 


PLUTEUS. 


PLU 


posed  to  be  fall  of  matter.    It  is 
used  in  opposition  to  vacuum. 

PHntht  a  square  member  forming  the 
lower  division  of  the  base  of  a 
column,  &c. ;  also  the  plain  pro- 
jecting face  at  the  bottom  of  a 
wall,  immediatelyabove  the  ground. 
In  (Gothic  architecture  the  plinth  is 
occasionallydivided  into  two  stages, 
the  tops  of  which  are  either  splayed 
or  finished  with  a  hollow  moulding, 
or  are  covered  by  the  base  mould- 
ings. 

PUnthf  the  square  footing  below  the 
bases  of  Ionic  and  Corinthian 
columns.  In  Grecian  architecture 
plinths  do  not  appear  to  have  been 
employed,  the  bases  of  the  columns 
resting  upon  the  upper  step  of  the 
building.  The  Latin  irord  pKnthus 
is  derived  from  the  Greek,  signifying 
a  tile. 

PUnfhuif  any  rectangular  parallelo- 
piped;  a  brick  or  tUe 

PUny,  whose  villas  were  by  the  Ro- 
mans objects  of  much  attraction, 
for  their  de&ign  and  ornament,  was 
a  person  of  excellent  judgment  in 
all  the  useful  arts,  and,  living  under 
Trajan,  had  an  opportunity  of  see- 
ing the  performances  of  and  ad- 
vising with  Apollodorus,  one  of  the 
greatest  architects  that  any  age 
producedr:  whether  artists  or  mas- 
ters employed  by  Pliny,  or  Pliny 
himself,  designed  these  villas,  is  not 
to  be  determined;  but  Pliny  was 
perfectly  acquainted  with  the  whole 
that  was  necessary  to  be  understood 
in  their  situation  and  disposition 

Plotting^  among  surveyor^,  the  art  of 
describing  or  laying  down  on 
paper,  &c.,  the  several  angles  and 
lines  of  a  tract  of  ground  surveyed 
by  a  theodolite  or  like  instrument, 
or  a  chain 

Plottingseale^  a  mathematical  instru- 
ment used  in  plotting  ground, 
usually  of  box-wood,  sometimes  of 
brass,  ivory,  or  silver,  either  a  foot 
or  a  foot  and  a  half  long,  and  about 
an  inch  and  a  half  broad 

Phtg-rod,  the  air-pump  rod  of  a 
Cornish  engine.  The  tappets  which 

342  ~~~ 


give  motion  to  the  valve  are  fixed 
upon  these  rods. 

Phunbf  in  ship-building,  signifies  to 
be  perpendicular 

Plumbago  forms  gray  tints  of  greater 
permanence  and  purity  than  most 
blacks  in  general  use,  and  it  is 
now  employed  for  this  purpose 
with  approved  satisftction  by  ex- 
perienced artists 

Phtmb'Une,  in  architecture,  &c.,  a 
line  perpendicular  to  the  horizon, 
made  by  dropping  a  plummet 

Phanmer-block,  a  short  carriage  or 
support  for  a  shaft  to  turn  in,  with 
a  flat  base  to  bolt  on  a  frame 

Phanmet,  in  carpentry,  navigation, 
&c.,  a  weight  of  lead  bung  on  a 
string,  by  which  depths  are  ascer- 
tained and  perpendicularity  dis- 
cerned 

Phan-treet  a  handsome  wood,  a  native 
of  Europe,  used  principally  in 
turning,  and  in  Tunbridge  vrarks ; 
in  the  endway  of  the  grain  it 
resembles  cherry-tree 

PhUt  in  algebra,  a  term  commonly 
used  for  more,  and  denoted  by  the 
character  + ,  as  6  +  10  »  16,  in 
contradistinction  to  — ,  or  mmuSj 
less,  as  16— 10»6 

PhiteuSt  the  wall  which  was  some- 
times made  use  of  to  dose  the  in- 
tervals between  the  columns  of  a 

'  building,  and  was  either  of  stone  or 
some  material  less  durable.  The 
latter  method  was  adopted  only  in 
places  under  cover,  whence  that 
kind  of  building  was  called  opus 
tntestmum.  The  pluteus  was  also 
a  kind  of  podium,  intervening  be- 
tween any  two  orders  of  columns 
placed  one  above  the  other.  The 
word  is  used  in  this  sense  in  the 
description  of  the  basilica  and  the 
scene  of  the  theatre.  The  pluteus 
has  been  adopted  between  every 
two  orders  of  columns  in  the  ex- 
terior of  all  the  theatres  and  am- 
phitheatres of  the  Romans  which 
are  known. 

Pluviometer,  in  the  arts,  a  nin- 
gauge,  an  instrument  to  measure 
the  quantity  of  rain  that  falls 


PLY 


POINTED  ARCHITECTURE. 


POL 


Plyerg,  in  mechanics,  a  kind  of  ba- 
lance used  in  piising  or  letting 
down  a  drawbridge 
Plying  to  wmdwardf  in  navigation, 
the  endeavouring  to  make  a  pro- 
gress against  the  wind 
Pneumatics,  the  properties  of  air  or 

fluids ;  a  branch  of  hydrostatics 
PnyjPt  a  name  given  to  a  place  near 
Athens,  at  which  assemblies  were 
held  for  oratory,  and  fojr  the 
discussion  of  political  aflfairs  of  the 
state ;  the  ancient  place  of  the  Athe- 
nian parliament.  It  was,  accord- 
ing to  Plutarch,  describing  the 
change  effected  by  the  Thirty 
Tyrants,  in  the  aspect  of  the  ora- 
tory, and  was  turned  from  the  sea 
in  order  to  divert  the  assembled 
people  from  being  reminded  by 
their  orators  of  maritime  affurs,  the 
basis  of  Athenian  dominion.  No 
traveller,  it  is  said,  has  hitherto  re- 
marked the  circumstance  of  the 
position  of  the  ancient  city  wail, 
by  which  the  Pnyx  was  doubtless 
enclosed  during  and  after  the  Pelo- 
ponnesian  war.  Plutarch  further 
remarks:  '< Themistocles  did  not 
bring  the  Piraeus  into  the  city,  as 
Aristophanes  would  have  had  it ;  but 
he  joined  the  city  by  a  line  of  com- 
munication to  the  Piraeus,  and  the 
land  to  the  sea."  This  measure 
strengthened  the  people  against 
the  nobility,  and  made  them  bolder 
and  more  intractable,  as  the  power 
came  with  wealth  into  the  hands 
of  masters  of  ships,  mariners,  and 
pilots.  Hence  it  was  that  the 
oratory  in  the  Pnyx,  which  was 
built  to  front  the  sea,  was  after- 
wards turned  by  the  Thirty  Tyrants 
towards  the  land,  as  they  believed 
a  maritime  power  to  be  inclinable 
to  a  democracy,  whereas  persons 
employed  in  agriculture  would  be 
less  uneasy  under  an  oligarchy. 
Podium,  in  Greek  architecture,  a 
continued  pedestal,  for  supporting 
a  row  of  columns,  or  serving  for  a 
parapet,  or  forminga  sort  of  terrace, 
as  the  podium  of  a  theatre  or  'am- 
phitheatre.   It  consists  of  a  plinth, 

343 


base^  die,  and  corona,  all  which 
were  continued  without  interrup- 
tion aroimd  three  sides  of  the 
building.  The  podium  was  also 
adopted  in  the  scenes  of  theatres ; 
and  here,  instead  of  being  unin- 
terrupted, it  was  frequently  broken 
round  the  basis  of  the  columns, 
and  formed  what  are  conmionly 
called  pedestals.  Vitruvius  seems 
to  consider  the  podium  as  a  pede- 
stal continued  the  whole  length  of 
a  building,  and  to  have  been  so 
called  both  when  there  were  pil- 
lars placed  on  it,  or  only  supported 
by  a  waU.  When  pillars  were 
placed  on  the  sides  of  buildings, 
sometimes,  instead  of  having  the 
podium  continued  the  whole  length  , 
in  one  line,  it  was  made  to  break 
forward  under  every  pillar,  which 
part  so  advancing  was  called  the 
stylobate,  and  that  which  was  be- 
twixt the  pillars  under  the  waU, 
was  the  podium. 

Pointed  or  Christian  Architecture 
had  its  rise  about  the  12th  century. 
Very  many  beautiful  examples  exist 
in  England.  It  was  also  employed 
in  Germany.  Mr.  W.  Pugin  says, 
that  Pointed  architecture  does  not 
conceal  her  construction,  but  beau- 
tifies it.  A  buttress  in  pointed  ar- 
chitecture at  ohce  shows  its  pur- 
pose, and  diminishes  naturally  as  it 
rises,  and  has  less  to  resist.  Here 
are  the  true  principles  of  Christian 
architecture,  by  the  conversion  of 
an  essential  support  of  the  building 
into  a  light  and  elegant  decoration. 

Point,  in  navigation,  one  of  the 
thirty-two  divisions  into  which 
the  circumference  of  the  horizon 
and  the  mariner's  compass  are 
distinguished,  each  comprehending 
11°  15' 

Point  cf  horse,  in  mining,  the  spot 
where  the  vein  is  divided  into  one 
or  more  branches 

Polaere,  in  navigation,  a  merchant 
vessel  of  the  Mediterranean,  having 
three  pole -masts,  without  tops, 
caps,  or  cross-trees,  with  a  bow- 
sprit of  one  piece 


-Or- 


POL 


POLYCHROMY. 


POL 


Polarization*  If  a  round  hailstone 
drop  upon  the  sloping  roof  of  a 
house,  it  will  act,  as  regards  its 
rebound,  just  in  the  same  manner 
whether  the  slope  be  towards  the 
north,  south,  east,  or  west.  But 
this  will  not  be  the  case  with  an 
arrow  under  the  same  circum- 
stances, because  it  has  a  distinction 
of  sides,  and  its  behaviour  will 
vary  according  as  the  plane  of  its 
barbs  is  parallel  with  the  eaves  or 
with  the  rafters  of  the  roof,  or  in- 
clined to  both.  A  bullet  in  its 
flight  from  a  gun  has  also  sides  to 
its  motion  (though  not  to  its  form), 
because  it  revolves  on  an  axis, 
which  may  be  vertical,  horizontal, 
or  inclined;  but  if  shot  from  a 
rifle,  it  has  no  such  sides,  because, 
though  spinning  on  an  axis,  that 
axis  has,  by  a  particular  contri- 
vance, been  made  to  coincide  with 
its  line  of  motion,  so  that  it  pre- 
sents the  same  aspect  above,  below, 
or  on  either  side.  Now  if  these 
projectiles  were  too  small  or  too 
rapid  for  us  to  discover  the  reason 
of  these  differences,  we  might  still 
observe  the  differences  themselves, 
and  should  express  them  by  saying 
that  the  motion  of  the  arrow  or  the 
gun-bullet  possessed  polarity,  or 
polarization,  which  was  not  the 
case  with  that  of  the  hailstone  or 
the  rifle-bullet.  Polarity,  then, 
means  simply  a  difference  of  sides. 
That  a  ray  of  light  should  (in 
some  cases)  possess  this  property, 
is  not  perhaps  so  wonderful  or  un- 
expected as  that  man  should  have 
been  able  to  detect  a  fact  so  refined 
and  remote  from  common  observa- 
tion, and  even  to  distinguish  dif- 
ferent varieties  of  it,  and  investi- 
gate its  laws.  Indeed,  these  must 
be  regarded  as  the  very  penetralia 
of  physics,  the  very  inmost  secrets 
of  Nature  that  man  has  been  en- 
abled  to  wrest  from  her.  If  the 
measurable  spaces  occupied  by  the 
waves  of  light  be  minute,  how  far 
less,  in  all  probability,  must  be 
those  immeasurable  spaces  to  which 

344 


its  vibrations  are  confined  (which 
even  in  sound  are  mostly  inappre- 
ciable, though  the  waves  occupy 
many  feet) ;  yet  it  is  to  the  posi- 
tions of  these  inconceivably  mi- 
nute vibrations  that  the  diflferenoes 
of  polarization  are  due. 

Poldway^  coarse  sacking  for  coal- 
sacks,  &c. 

Pok-mastit  in  navigation,  are  those 
made  of  single  trees  or  spars,  in 
contradistinction  to  those  made  of 
several  pieces 

Pok-plate,  a  small  wall-plate  used  in 
roofs  to  receive  the  pitch  of  the 
rafters 

Polroz,  in  mining,  the  pit  underneath 
a  water-wheel 

Polychromy  is  the  art  and  practice 
of  painting   in   positive   colours, 
either  on  flat  siufaces  or  sculp- 
tured forms,  and  has  been  referred 
for  its  origin  to  other  than  aesthe- 
tic motives.    The  object  of  poly- 
chromy is  to  heighten  the  eflTect  of 
architectural  decoration,  either  by 
causing  a  more  just  subordination 
of  the  various  parts  than  can  be 
obtained  by  mere  chiaro-scuro,  or 
in  supplying  deficiencies  that  could 
not  be  so  well  filled  up  by  any 
other  means.   Professor  Cockerell, 
who  travelled  and  learned  much 
in    Greece,    was    the   first    who 
brought  it  to  light  in  this  coun- 
try.   This  very  interesting  deco- 
rative art  had  its  origin  doubtless 
in  Egypt ;  but  the  Greeks  excelled, 
as  in  all  art,  by  the  existing  evi- 
dence of  the  temples  of  their  per- 
fection of  .architectural  art.     The 
interior  decorations  of  Pompeii  are 
also  evidences  of  a  refinement  of 
taste,  and  in  Gothic  polychromy 
the  designers  and  operatives  have 
shown  some  talent.     A  free  and 
bold  style  in  arabesque  prevailed 
from  the  time  of  Henry  III.  until 
the  close  of  the  reign  of  Edward 
III.     Bright    and   lively  colours 
were  applied  to  masses,  and  the 
grounds  covered  with  compositions 
of  foliage  and  birds,  animals  and 
human  figures ;  sometimes  in  one 


POL 


PORCH. 


POR 


tint,  sometimes  in  varied  colours, 
lilany  beautiful  examples  still  exist 
in  our  cathedrals  and  some  parish 
churches. 

PolyfoUy  an  ornament  formed  by  a 
moulding  disposed  in  a  number  of 
segments  of  circles 

Polystylcy  having  a  number  of  co- 
lumns. Where  columns  occur  bie- 
hind  columns,  as  where  a  portico 
has  inner  columns,  like  that  of  the 
Royal  Exchange,  such  portico  may 
be  termed  polyttyle, 

Pomel,  a  boss  or  knob  used  as  an  or- 
namental  top  of  a  conical  or  dome- 
shaped  roof  of  a  turret,  &c.  A 
large  copper  ball  or  pomel  is  on 
the  summit  of  a  timber  spire  of 
Lincoln  cathedral 

Pom  (Latin),  a  bridge.  The  most 
ancient  bridge  upon  record  is  the 
one  erected  by  Nitocris  over  the 
Euphrates  at  Babylon. 

Poon  wood,  of  Singapore,  is  of  a  light 
porous  texture,  and  light  greyish 
cedar  colour;  it  is  used  in  ship- 
building for  planks,  and  makes  ex- 
cellent spars.  The  Calcutta  poon 
is  preferred. 

Poplar  wood.  There  are  five  species 
common  to  England,  of  which  the 
abeUf  or  great  white  poplar,  and  the 
Lombardy  poplar,  are  most  used. 
The  woods  are  soft,  light,  easy  to 
work,  suited  for  carving,  common 
turnery,  &c. 

Poppets,  perpendicular  pieces  that  are 
fixed  on  the  fore  and  aftermost 
parts  of  the  bulgeways,  to  support 
the  ship  while  heing  launched 

Poppet-head,  that  part  of  a  lathe 
which  holds  the  back  centre,  and 
can  be  fixed  on  any  part  of  the 
bed 

Poppy,  an  ornament  representing  the 
poppy-head,  used  on  the  tops  of 
the  upright  ends  or  elbows  which 
terminate  seats,  &c.  in  churches 

Peppy-head,  in  architecture,  a  carved 
ornament  at  the  apex  of  a  standard 
or  open  seats  in  Gothic  churches, 
also  carved  into  an  ornamental 
finial,  pomel  or  crest,  &c. 

Porcelain  clay,  in  mineralogy,  a  sub- 

345 


stance  of  great  infiisibility,  derived 
from  disintegrated  felspar 

Porch,  in  architecture,  a  roof  sup- 
ported on  pillars  before  a  door;  a 
kind  of  vestibule  supported  by  pil- 
lars.  Any  small  portico  consider- 
ably lower  than  the  main  structure 
to  which  it  is  attached  may  be  so 
termed,  in  contradistinction  from 
one  carried  up  the  height  of  the 
building,  or  as  high  as  the  prindpal 
cornice.  Porches  were  used  in  Nor- 
man architecture,  in  Early  English, 
and  commonly  in  subsequent  dates. 
When  the  fasMon  of  building  houses 
on  quadrangular  plans  was  discon- 
tinned,  a  porch  of  at  least  two 
stories,  and  sometimes  the  whole 
heightof  the  l^uilding,  succeeded  the 
gate-house.  Low  porches  had  been 
used  as  entrances  frt)m  inner  courts 
from  an  early  date;  and  of  the 
time  of  Henry  VIIL  one  may  be 
mentioned  at  Cowdry,  attached  to 
the  door  leading  from  the  court  to 
the  hall. 

Pores,  small  interstices  between  the 
solid  particles  of  bodies 

Porisms,  in  geometry,  a  name  applied 
by  the  ancients  to  cwtain  compre- 
hensive and  indefinite  problems 

Port,  in  navigation,  the  larboard  or 
left  side  of  a  ship ;  as  *  a-keel  to 
port'  is  an  inclination  to  the  lar- 
board side 

Ports,  the  holes  in  the  ship  to  run 
the  guns  out 

Port-ltds,  shutters  to  the  ports 

Ports  and  buildings  constructed  in 
water.  Yitruvius writes:  "The  op- 
portunity which  presents  itself  of 
giving  some  account  of  ports,  and 
by  what  means  protection  may  be 
afforded  to  ships  frt>m  the  elements, 
ought  not  to  be  neglected.  The 
positions  best  adapted  by  nature  to 
such  a  purpose  are  bays  with  capes 
and  promontories  at  their  extremi- 
ties, from  which  the  shore  recedes 
inwardly  in  a  curved  line.  Upon 
shores  of  this  description,  docks 
may  be  built  or  porticoes  erected, 
or  a  channel  cut  from  the  port  to 
the  emporium,  defended  by  towers 


POR 


PORTICUS. 


POR 


on  each  side,  in  which  machines 
may  be  constructed  for  throwing 
booms  across  the  passage.  If,  how- 
ever,  no  situation  can  be  found 
capable  by  its  formation  of  protect- 
ing yessels  against  the  violence  of 
the  sea,  we  must  search  for  a  spot 
where  a  promontory  presents  itself 
on  one  side,  and  where  no  river 
discharges  itself  so  as  to  oppose  its 
application  to  the  purposes  of  a 
harbour,  and  supply  the  want  of  a 
corresponding  projection  on  the 
other  by  bttUding  walls  and  but- 
tresses.  The  wiUls,  which  it  be- 
comes necessary  in  this  case  to 
construct  in  the  water,  may  be 
thus  formed :  sand  should  fir&t  be 
procured  from  that  part  of  the 
coast  lying  between  Camac  and 
the  promontory  of  Minerva,  and 
mixed  with  lime  in  the  proportion 
of  two  parts  to  one ;  then  rows  of 
grooved  beams  must  be  driven  in 
the  water,  connected  by  oaken 
planks,  and  bound  together  by 
chains.  The  surface  of  the  ground 
below  the  water,  on  which  the 
wall  is  to  be  raised,  must  then  be 
made  evenbymeans  of  traDstilli,and 
the  space  comprehended  between 
the  beams  filled  with  a  composi- 
tion consisting  of  rough  stone  and 
cement,  made  in  the  manner  just 
described.  Such  is  the  quality  of 
the  sand  produced  in  these  spots, 
that  the  composition  becomes  a 
solid  wall.'' 

Port  the  helm.  In  navigation  this 
phrase  directs  a  ship's  course  fur- 
ther to  the  right,  or  starboard,  by 
putting  the  helm  to  larboard. 

Porta  (Latin),  the  gate  of  a  dty,  cita- 
del, or  other  open  space,  enclosed 
by  a  wall,  in  contradisthiction  to 
Janua,  which  was  the  door  or 
entrance  to  any  covered  building 

Portaif  the  arch  over  a  door  or  gate- 
way ;  an  entrance  under  cover 

Porteullia,  a  strong  defensive  frame- 
work of  timber,  hung  in  grooves 
within  the  chief  gateway  of  a  fort- 
ress,  or  a  castle,  or  an  edifice  of 
safety :  it  resembles  the  harrow,  but 


is  placed  vertically,  having  a  row  of 
iron  spikes  at  the  bottom,  and  islet 
down  to  stop  the  passage  in  case 
of  assault 
Portieot  in  architecture,  a  covered 
walk  supported  by  columns,  and 
usually  vaulted ;  a  piazza  or  arched 
pathway.    (For  the  different  plans 
and  denominations  of   porticoes, 
see   *  Rudimentary  Architecture,' 
Part  I.) 
Porticua  (Latin),  a  walk  covered  with 
a  roof   which   is    supported    by 
columns.      A  portico  was  either 
attached  to  temples  and    public  | 
buildings,  or  it  was  built  indepen- 
dent of  any  other  edifice. 
Porticusideinde),  In  the  houses  of  the 
Roman  citizans,  between  the  atrium 
(hall,  or  servants'  room)  and  the 
inner  court,  there  was  usually  a 
room  called  the  tabBnum  (corri- 
dor) ,  mentioned  by  Vitruvius.  This 
porticus  lay  betwixt  the    atrium 
and  the  cavasdium.     The  reason 
for  his  giving  it  this  round  form 
maybe  upon  two  accounts:  first, 
to  give  a  greater  grace  to  its  pro- 
jection, and  to  make  the  fore  part 
of  it  serve  for  a  more  beautiful 
vestibulmn  to  the  house;  and  in  the 
next  place,  as  being  designed  for  a 
shelter  in  tempestuous  weather,  it 
the  better  broke  the  force  of  those 
winds  that  blew  on  that  side  than 
if  it  had  been  more  square. 
Porticw.    By  the  Romans  this  was 
a  common  name  given  to  all  build- 
ings that  had  walks   under  the 
cover  of  a  roof  or  ceiling,  sup- 
ported  by   pillars    or    pilasters, 
though  difi^rently  called,  according 
to  the  disposition  of  the  pillars : 
when  placed  on  the  outside  of  a 
building,  as  round  some  of  their 
temples,  it  was  called  per^terium  ; 
when  these  ranges  of  pillars  were 
within  a  room,  as  they  were  some- 
times in  their  tricUnia,  baaiUea, 
atriOf  and  temples,  the  void  space 
betwixt  the  pillars  and  the   side 
walls  was  called  ala;  but  when 
pillars  surrounded  courts,  and  had 
walks  betwixt  them  and  the  walls, 


346 


POR 


PRESSURE  OF  FLUIDS. 


PRI 


these  ranges  of  pillars  were  called 
jferistylia,  and  the  Walk  betwixt 
was  called  hporticua 
Portland-stone,  an  alkaline  sandstone, 
of  a  dull  whitish  colour,  heavy  and 
moderately  hard,  and  somewhat  flat 
texture,  and  composed  of  large 
rounded  grit,  cemented  together 
by  an  earthy  spar,  and  intermixed 
with  numerous  glittering  spangles 
of  pure  spar :  the  grit  splits  in  the 
cutting  of  the  stone,  so  that  it  is 
capable  of  being  brought  to  a  sur- 
face very  smooth  and  equal:  it  vrill 
not  strike  fire  with  a  steel,  and 
burns  to  a  slight  ashen  hue.  It 
has  been  and  is  much  used  for  all 
kinds  of  buildings,  particularly  in 
the  large  structures  in  London :  it  is 
brought  from  the  island  of  Portland, 
in  Dorsetshire 

Post,  an  upright  timber  in  a  building; 
those  used  in  modem  roofs  are 
called  king*posts  or  queen-posts, 
according  to  their  number  and 
position 

Post  Meridiem  (PM.),  after  mid-day 

Postern,  a  small  doorway  or  gateway 
at  the  back  of  a  building ;  a  small 
doorway  for  private  communica- 
tion  with  the  exterior  of  a  castle 
or  fortress 

Postigue,  in  architecture,  an  orna- 
ment of  sculpture  superadded  when 
the  original  plan  luis  been  com- 
pleted 

Pot-metal,  a  species  of  stained  glass, 
the  colours  of  which  are  incorpo- 
rated within  the  glass  while  in  a 
state  of  fusion 

Poudrette,  a  French  word,  signify, 
ing  powdered  dung ;  but  the  word 
is  applied,  when  treating  of  human 
excrement,  in  its  meaning  to  the 
solid  of  that  soil  after  the  liquid 
manure  has  discharged  itself.  In 
a  vine-growing  district  near  Paris, 
(See  article  Fosses  d^aisances,)^\i- 
drette  was  used  for  manure,  and, 
although  the  application  of  it  pro- 
duced  a  great  abundance  of  fruit, 
yet  the  vrine  proved  very  inferior 
to  that  which  had  been  previously 
made  on  the  same  ground. 

347 


Power,  in  mechanics:  this  denotes  a 
force  which,  being  applied  to  a 
machine,  tends  to  produce  motion 
or  pressure 

Power,  horse,  in  mechanics,  an  ex- 
pression used  to  denote  the  power 
of  a  steam  engine,  that  is  to  say, 
how  many  horses'  work  it  will  save. 
If  a  horse  standing  still  can  by  his 
strength  keep  a  weight  of  169  ibs. 
from  falling,  when  suspended  over 
a  pulley,  he  will  exert  121  ibs,  at 
two  mUes  per  hour;  100 lbs.  at 
three;  8 libs,  at  four;  64  lbs.  at  five; 
49  lbs. at  six;  36 lbs.  at  seven;  25 ibs. 
at  eight;  16 lbs.  at  nine;  9 lbs.  at 
ten;  4 ibs.  at  eleven;  and  lib.  at 
twelve  miles  per  hour. 

Power-loom,  in  mechanics,  a  loom 
moved  by  the  mechanical  force  of 
steam,  wind,  water,  &c.,  as  contra- 
distinguished  from  hand-weaving 

PoynteU,  paving  formed  into  small 
lozenges  or  squares  laid  diagonally 

PrtBcinctiones,  the  passages  or  corri- 
dors which  separated  the  several 
ranges  of  seats  in  an  ancient  Ro- 
man theatre 

Pressure  qfjluids  consists  of  two  kinds, 
elastic  and  non-elastic.  The  first 
is  comprehended  in  the  science  of 
pneumatics,  the  second  in  that  of 
hydrostatics.  Both  classes  of  fluids 
deviate  from  solid  substances  in 
their  greater  distribution  of  any 
pressure  to  which  they  may  be 
subjected.  Thus  solid  bodies  press 
downwards  only  by  the  force  of 
gravity ;  all  fluids,  on  the  contrary, 
press  not  only  in  this  direction, 
but  upwards,  sideways,  and  every 
way  equally.  The  incompressi- 
bility  of  water  renders  it  service- 
able,  by  this  principle,  in  the  hy- 
drostatic press. 

PreveTiter  bolts,  those  which  are 
driven  at  the  lower  end  of  the  pre- 
venter plates,  to  assist  the  strain  of 
the  chiUn  bolts 

Preventer  plates,  in  ships,  plates  of 
iron  below  the  links  of  the  chains 

Pricker,  a  thin  piece  of  iron,  used  to 
make  a  hole  for  the  fusee  or  match 
to  fire  a  blast 


PRI 


PRIORY. 


PRI 


Prittf  a  solid  piece  of  ore,  a  spedmen 

Primmfft  the  effect  engendered  by 
having  too  little  steam  room  in  the 
boiler  of  a  steam  engine.  Minute 
particles  of  water  being  carried  into 
the  cylinder,  collect  in  a  body, 
which  obstructs  the  passage  of  the 
piston,  and  causes  a  considerable 
loss  of  power. 

Princess  metal,  in  metallurgy,  an  alloy 
of  copper,  in  imitation  of  silver,  in 
which  the  proportion  of  zinc  is 
greater  than  in  brass 

Principal  braee^  a  brace  immediately 


under  the  principal  rafters  or  ]»- 
rallel  to  them,  in  a  state  of  com- 
pression, assisting  with  the  princi- 
pals to  support  the  timbers  of  a 
roof :  they  are  employed  in  the  pre- 
sent roof  of  St.  Paul's  church, 
Covent  Garden 
Priory,  a  monastic  establishment  for 
the  devotional  requirements  and 
maintenance  of  a  religious  frater- 
nity, under  the  government  of  a 
prior.  Many  priories  were  for- 
merly scattered  over  Britam,  as 
the  subjoined  list  will  show : 


NAMB. 

Abergavenny 
Abemethy  . 
Acombury  . 
Alberbury  . 
Aldeby  .  . 
AUensbome* 
AU  Saints  . 
Alvingham  . 
Andover  .  . 
Anglesey .  . 
Appledereomb 
Ardchattan  . 
Astley  .  . 
Aucot .  .  . 
Austin  of  Braden 

stoke  .  . 
Austin  Friars 
Austin    Priory 

Bradley  . 
Austin   Priory 

Mickleham 
Austin  Priory 
Badlesmere  . 
Bamborough 
Banester 
Bareham .  . 
Barlinch .'  . 
Barnstaple  . 
BamweU .  . 
Bartholomew  (St.) 
Basedale .  . 
Beaston  .  . 
Beaulieu .  . 
Beanvale 
Bees  (St.)  . 
Belton-Grace-Dieu 
Belvoir  .  . 
Bezdon   .    . 


of 
of 


} 

} 
} 


ORDBK. 

Benedictine 

Augustine 

Do. 

Black  Monks 

Augustine 
IDo. 


Augustine 
Benedictine 
Vallis  Caulium 
Benedictine 


Augustine 


Do. 

Do. 

Do. 

Do. 

Do. 

Do. 

Crutched  Friars 

Augustine 

Cluniae 

Augustine 

Do. 

Cistercian 

Augustine 

Vallis  Caulium 

Carthusian 

Benedictine 

Augustine  * 

Benedictine 

Augustine 


DATB. 

Wm.  Conq. 

1273 

King  John 

Henry  I. 

1355 

1466 

1166 

King  Stephen 


Henry  III. 

1230 
Wm.  Conq. 

1151 

1142 
1253 
1230 

Henry  III. 

1358 

Edward  II. 

Henry  I. 

1182 

Edward  I. 

Henry  II. 

Wm.  Conq. 

1092 

1133 

1162 
King  John 

1230 
Edward  III. 
Wm.  Rufus 

1277 

1076 

1343 


COUNTY. 

Monmouthshire 

Perthshire 

Herefordshire 

Shropshire 

Norfolk 

Suffolk 

Dublin 

Lincolnshire 

Hampshire 

Cambridgeshire 

Hampshire 

Argyleshire 

Worcestershire 

Warwickshire 

Wiltshke 

Middlesex 

Leicestershire 

Sussex 

Middlesex 

Kent 

Northumberiand 

Oxfordshire 

Cambridgeshire 

Somersetshire 

Devonshire 

Cambridgeshire 

Middlesex 

Yorkshire 

Norfolk 

Ross-shire 

Nottinghamshire 

Cumberland 

Leicestershire 

Lincolnshire 

Essex 


348 


PRI                                               PRIORIES. 

PRI 

NAME. 

ORDER. 

DATE. 

COONTy. 

Bicknacre     .... 

Augustine 

Henry  II. 

Essex 

Bilsington 

Do. 

1253 

Kent 

Binham  . 

Benedictine 

Henry  I. 

Norfolk 

Birkenhead 

Do. 

Henry  II. 

Cheshire 

Bissemede 

Augustine 

Henry  II. 

Bedfordshire 

Bithkalest    , 

Do. 

1283 

Caernarvonshire 

Blackburn    . 

Do. 

Northumberland 

Blackmore    . 

Black  Monks 

King  John 

Essex 

Blantyre 

Augustine 

1296 

Lanarkshire 

Blighburgh  . 

Do. 

Henry  I, 

Suffolk 

Blythe     .     . 

Benedictine 

1088 

Nottinghamshire 

Bodmin  .     . 

Augustine 

1120 

Cornwall 

Bolton    .    . 

Do. 

1120 

Yorkshire 

Borgrove 

Benedictine 

Henry  I. 

Sussex 

Botolph  (St. 

)    ' 

Augustine 

Henry  I. 

Essex 

Bourn      .     . 

Do. 

1138 

Lincolnshire 

Bradenstoke 

Do. 

980 

WUtshire 

Bradley   .     . 

Do. 

King  John 

Leicestershire 

Bradwell .     . 

Benedictine 

King  Stephen 

Buckinghamshire 

Brecknock   . 

Do. 

Henry  I. 

Brecknockshire 

Bredon    .     . 

Augustine 

1144 

Leicestershire 

Bridgetown  . 

Do. 

1375 

Cork 

Bridlington  . 

Do. 

Henry  I. 

Yorkshire 

Bridport .     . 

Dorsetshire 

Brimsfield    . 

Benedictine 

Gloucestershire 

Brinkburge  . 

Augustine 

Henry  I. 

Northumberland 

Brisite     .     . 

Do. 

1110 

Suffolk 

Bromehill    . 

Do, 

Henry  III. 

Norfolk 

Bromere  .    . 

Do. 

Henry  I. 

Hampshire 

Bromfield     . 

Benedictine 

1155 

Shropshire 

j     Bromholm    . 

Cluniac 

1113 

Norfolk 

i     Brooke    .    . 

Augustine 

Richard  I. 

Rutlandshire 

Bruton    .     . 

Do. 

1005 

Somersetshire 

Buckenham, 

Oli 

i    '. 

Do. 

King  Stephen 

Norfolk 

Bullington    . 

Gilbertine 

King  Stephen 

Lincolnshire 

Borscough   . 

Augustine 

Richard  I. 

Lancashire 

Bustlesham  . 

Do. 

1338 

Berkshire 

Butley     .     . 

Do. 

1171 

Suffolk 

Byrkley  .     . 

Do. 

1199 

Somersetshire 

Caermarthen 

Do. 

1148 

Caermarthenshire 

Calderell.    . 

Do. 

1152 

Bedfordshire 

Camper   .    . 

Do. 

1244 

Suffolk 

Canonby .    . 

Do. 

1296 

Roxburghshire 

Canons  Ashb 

V  . 

• 

Do. 

King  John 

Northamptonshire 

CanwcU  .     . 

Benedictine 

1142 

Staffordshire 

Cardiflf    .     . 

Do. 

Glamorganshire 

Cardigan .     . 

Cistercian 

1291 

Cardiganshire 

Careswell     . 

Cluniac 

Edward  I. 

Devonshire 

Carisbrooke . 

Augustine 

1071 

Hampshire 

Cartmele .    . 

Do. 

1188 

Lancashire 

Castleacre    . 

Cluniac 

1085 

Norfolk 

Castle  Hymel    . 

Augustine 

King  John 

Northamptonshire 

Catteley I 

Gilbertine 

King  Stephen 

Lincolnshire 

349 


PRI 

PRIORIES. 

PRI 

NAME. 

ORDER, 

DATE. 

COUNTY. 

Charletan     .... 

Premonstrant 

1187 

WUtshire 

Chaucomb    .    . 

Augustine 

King  John 

Northamptonshire 

Chepstow     .    . 

Benedictine 

King  Stephen 

Monmouthshire 

Chetwood    .     . 

Augustine 

1244 

B  uckinghamshire 

Chicksand    .    . 

Gilbertine 

1150 

Bedfordshire 

Chiplcy   .    .    . 

Augustine 

1468 

Suffolk 

Chirborg .    .    . 

Do. 

Henry  III. 

Shropshire 

Christchurch    . 

Do. 

1150 

Hampshire 

Christchurch    . 

Do. 

1108    1 

Middlesex,  withiii 
Aldgate 

Clare  .... 

Do. 

1248 

Suffolk 

Clattercote  .    . 

Gilbertine 

King  John 

Oxfordshire 

Clifford    .    .    . 

Cluniac 

Henry  I. 

Herefordshire 

Cogges    .    .    . 

Augustine 

Oxfordshire 

Cokesford    .    . 

Do. 

Henry  III. 

Norfolk 

Cold  Norton     . 

Do. 

Henry  II. 

Oxfordshire 

Coldingham .     . 

Do. 

673 

Scotland 

Coningshead 

Do. 

Henry  II. 

Lancashire 

Covenham    .    . 

Benedictine 

1082 

Lincolnshire 

Coventry .    .    . 

Do. 

1043 

Warwidcshire 

Cranbourne  .    . 

Do. 

980 

Dorsetshire 

Creak.    .    .    . 

Augustine 

1226 

Norfolk 

Cresswell     .    . 

King  John 

Herefordshire 

Crusay     .    .     . 

Do. 

St.  Columba 

Argyleshire 

Cumbwell    .    , 

Do. 

Henry  II. 

Kent 

Daventry     .     . 

Cluniac 

Wm.  Rufus 

Northamptonshire 

Denestro .     .     . 

Benedictine 

Wm.  Conq. 

Somersetshire 

Denhurst     .    . 

Do. 

980 

Gloucestershire 

Dennis  (St.)     . 

Augustine 

1124 

Hampshire 

Depyng  .     .     . 

1139 

Lincolnshire 

Dodnash .    .    . 

Do. 

Edward  I. 

Suffolk 

Dorley     .    .    . 

Do. 

Henry  I. 

Devonshire 

Dover     .    .    . 

Benedictine 

1140 

Kent 

Drax  .... 

Augustine 

Henry  I. 

Yorkshire 

Dudley    .    .    . 

Cluniac 

1161 

Staffordshire 

Dunmow      .     . 

Augustine 

1104 

Essex 

Dunstable    .     . 

Do. 

Henry  I. 

Bedfordshire 

Earles  Colne 

Benedictine 

Henry  I. 

Essex 

Easeboum    .    , 

Nunnery 

Henry  III. 

Do. 

Edington 

Augustine 

1358 

Wiltshire 

Edithweston 

Benedictine 

Henry  I. 

Rutlandshire 

EUerton  .     . 

Gilbertine 

1212 

Yorkshire 

EUesham  .   . 

Augustine 

1166 

Lincolnshire 

Eltham    .    . 

Do. 

1166 

Do. 

Epworth .    . 

Carthusian 

Richard  II. 

Do. 

Erdbury  .    . 

Augustine 

Henry  II. 

Warwickshire 

Essehold .    . 

Cistercian 

1172 

Yorkshire 

Eston      .    . 

Trinity 

Henry  III. 

WUtshire 

Everdon  .    . 

1217 

Northamptonshire 

Ewcnny  .    . 

Benedictine 

1141 

Glamorganshire 

Ewyas     .    . 

Do. 

1100 

Herefordshire 

Eye    .    .    . 

Do. 

Wm.  Conq. 

Suffolk 

Farley     .    . 

Cluniac 

II25 

WUtshire 

350 


P:EtI                                              PRIORIES. 

PRI 

NAlfX. 

ORDER. 

DATE. 

COUNTY. 

Teale  .    .    . 

•         * 

Cluniac 

Ayrshire 

Tilley.    .    . 

Augustine 

1156 

Nottinghamshire 

Finehale  .    . 

Benedictine 

1196 

Durham 

Planesford   . 

Augustine 

1347 

Herefordshire 

Plitcham      .    . 

Do. 

Ricbard  I. 

Norfolk 

Folkestone  .    . 

Benedictine 

630 

Kent 

Fordham .    .    . 

Gilbertine 

Henry  III. 

Cambridgeshire 

Frainpton     .    . 

Black  Monks 

Wm.  Conq. 

Dorsetshire 

Freston    .    .    . 

• 

1114 

Lincolnshire 

Frothelstoke 

Augustine 

1220 

Devonshire 

Fy  vie  .... 

1179 

Aberdeenshire 

German  (St.) 

Augustine 

Henry  I. 

Cornwall 

Gilbcrtine     .     , 

Gilbertine 

1291 

Cambridge 

Gilbertine    .    . 

Sempring. 

1212 

Yorkshire 

Goldcliff.    .    . 

Augustine 

1113 

Monmouthshire 

Greenfield    .    . 

Cistercian 

1153 

Yorkshire 

Griesly    .    .    , 

Augustine 

Henry  I. 

Derbyshire 

Grosmont     .    . 

Yorkshire 

Gwenny  .    .    . 

• 

1141 

Glamorganshire 

1     Gysburgh     .    . 

Do. 

1129 

Yorkshire 

1     Hackness     .    . 

William  II. 

Do. 

1     Hagh       .    .    . 

Augustine 

1164 

Lincolnshire 

1     Haltempraie 

Do. 

1324 

Yorkshire 

1     Hampton     .    . 

Do. 

Henry  I. 

Norfolk 

1     Hanepole     .    . 

Cistercian 

1170 

Yorkshire 

Harwolde    .    , 

Augustine 

1150 

Bedfordshire 

Hasilberge  .    . 

Do. 

1150 

Somersetshire 

Hastings      .     . 

Do. 

Ricbard  I. 

Sussex 

Hatfield  Broadoak . 

Benedictine 

Henry  I. 

Essex 

Hatfield  Peverell   . 

Do. 

Henry  I. 

Do. 

Hatfield  Regis  .     . 

Black  Monks 

1135 

Do. 

Haverfordwest . 

Augustine 

1200 

Pembrokeshire 

Haverholm  .    . 

Sempring. 

1137 

Lincolnshire 

Hedley    .    .    . 

1125 

Yorkshire 

Helagh    .    .     . 

Augustine 

1203 

Do. 

Helen's  (St)    . 

Cluniac 

1155 

Hampshire 

Heringham  .    . 

Augustine 

1472 

Sussex 

Herringfleet 

Do. 

Henry  III. 

Suffolk 

Hertford      .     . 

Benedictine 

1223 

Hertfordshire 

Hertland.    .    . 

Augustine 

1000 

Devonshire 

HickHng       .     . 

Do. 

1185 

Norfolk 

Hinkley  .     •     . 

Benedictine 

1173 

Leicestershire 

Hinton    .    .     . 

Cartbasian 

1222 

Somersetshire 

Hitehen  .    .    . 

Gilbertine 

Edward  III. 

Hertfordshire 

Holland  .     .     . 

Benedictine 

1319 

Lancashire 

Holland  Brigge 

Sempring. 

King  Jobn 

Lincolnshire 

Holme    .    .    . 

Cluniac 

1291 

Dorsetshire 

Holyconrt    .     . 

Benedictine 

Saxon  period 

Norfolk 

Holy  Trinity     . 

Do. 

1089 

York 

Holywood    . 

Premonstrant 

1296 

Kirkcudbrightshire 

Horkesley  Panri 

i    . 

Cluniac 

Henry  II. 

Essex 

Hornby  .    . 

Premonstrant 

Lancashire 

Horncinirdi 

1         •        • 

Henry  II. 

Essex 

351 


PRI 


PRIORIES. 


PRI 


NAME. 

OBDER. 

DATE. 

COD  NTT. 

Horsham      .    .    .     . 

Benedictine 

1105 

Norfolk 

Horsley   .    . 

; 

Wm.  Conq. 

Gloucestershire 

Hounslow    . 

Trinity 

Edward  I. 

Middlesex 

Hoxne     .     . 

Benedictine 

Suffolk 

Huntingdon . 

Augustine 

King  Steph. 

Huntingdonshire 

Hurley    .    . 

Benedictine 

William  I. 

Berkshire 

Hyrst.     .     .     . 

Augustine 

Henry  I. 

Lincolnshire 

Ipswich  *     . 

Do. 

1177 

Suffolk 

Isle  of  May 

Do. 

David  I. 

Fifeshire 

Ives  (St.)     . 

Benedictine 

1001 

Huntingdonshire 

Ivychurch    . 

Augustine 

Henrv  II. 

• 

Wiltshire 

Ixworth  .     . 

Do. 

1100 

Suffolk 

Kersey    .     .     . 

Do. 

Edward  III. 

Do.  . 

Kidwelly 

Benedictine 

1130 

Caermarthenshire 

Kilcomin      .     . 

Do. 

1184 

Tipperary 

Kilpeck   .     . 

Do. 

rierefordishire 

Kingston      .     . 

Carthusian 

Edward  III. 

Yorkshire 

Kirby  Beler 

Augustine 

1359 

Leicestershire 

Kirkham      .     . 

Do. 

^      1121. 

Yorkshire 

Knaresborough 

Trinity 

King  John 

Do. 

Kyme      .     .     . 

Augustine 

Henry  II. 

Lincolnshire 

Lancaster     .    . 

Benedictine 

1004 

Lancashire 

Lanercost     .     . 

Augustine 

1169 

Cumberland 

Lantony       .     . 

Do. 

1108 

Monmouthshire 

Lantony       .     . 

Do. 

1136 

Gloucestershire 

Lapley    ... 

Black  Monks 

£dw.  Conf. 

Staffordshire 

Latteu     .     .     . 

Augustine 

1270 

Essex 

Launceston 

Do. 

1126 

Cornwall 

Laund     .     .     . 

Do. 

1125 

Leicestershire 

Leeds      .     .    . 

Do. 

1119 

Kent 

Lees,  or  Lighes 

Do. 

Henry  III. 

Essex 

Lenton    .     .     . 

Cluniac 

Henry  I. 

Nottinghamshire 

Leominster  .     . 

660 

Herefordshire 

Letheringham 

Aug^ine 

Suffolk . 

Lewes      .     . 

Cluniac 

1078 

Sussex 

Lintin     .     .     . 

Henry  III. 

Cambridgeshire 

Lochleven    .     , 

Augustine 

Kinross-shire 

Loch  Tay     . 

Do. 

Alex.  1. 1122 

Perthshire 

Lodrcs     .     .     . 

Henry  I. 

Dorsetshire 

Long  Beuningt( 

)n  . 

Cistercian 

1175 

Lincolnshire 

Longlent      .    . 

Augustine 

1291 

Wiltshire 

Lynn       ... 

Benedictine 

1100 

Norfolk 

Lythom  .     .     . 

Do. 

1291 

Lancashire 

Luffield   .     . 

Do. 

1124 

Northamptonshire 

Mabberly     . 

Augustine 

1206 

Cheshke 

Maldon   .    . 

Carmelite 

1292 

Essex 

Malvern  Major 

Benedictine 

1083 

Worcestershire 

Malvern  Minor      , 

Do. 

1171 

Do. 

Mardin  Bradley     . 

Augustine 

King  Stephen 

WUtshire 

Markby  .    .    . 

Do. 

Henry  II. 

Lincolnshire 

Marlborough    .     , 

Gilbertine 

King  John 

Wiltshire 

Maimond     .     .     . 

Do. 

Richard  I. 

Cambridgeshire 

Marstoke     .    . 

• 

Augustine 

1336 

Warwickshire 

352 


'   PR! 


PRIORIES. 


PRI 


NAME. 

ORDER. 

DATE. 

COUNTY. 

Martin  (St.)      .     .     . 

• 

Kent 

Aiassingham  Magna  . 

Augustine 

1260 

Norfolk 

Mattersey    .... 

Gilbertine 

1192 

Nottinghamshire 

Maxtoke      .... 

Augustine 

1336 

Warwickshire 

Alay 

Dayid  I. 

Fifeshire 

Melton  Mowbray  .    . 

Cluniac 

Leicestershire 

Mendham    .... 

Do. 

King  Stephen 

Suffolk 

Menton 

Augustine 

1196 

Yorkshire 

Mereyal 

Cistercian 

King  Stephen 

Warwickshire 

Mersey 

Benedictine 

Edw.  Conf. 

Essex 

Merton 

Augustine 

1121 

Surrey 

Michael  (St.),  Mount . 

Benedictine 

Edw.  Conf. 

Cornwall 

Minster  Loyel  .    .    . 

Do. 

King  John 

Oxfordshire 

Mixhalham       .    .    . 

Augustine 

Henry  III. 

Sussex 

Modbury     .... 

Benedictine 

King  Stephen 

Deyonshire 

Molycourt    .... 

Do. 

Wm.  Conq. 

Norfolk 

Monimusk    .... 

Augustine 

r  William 
\  the  Lion 

Aberdeenshire 

Monk  Breton    .    .    . 

Cluniac 

Yorkshire 

Monkland    .... 

Benedictme 

Henry  II. 

Herefordshire 

Monks  Horton      .    . 

Cluniac 

Henry  II. 

Kent 

Monks  Kirby    .    .    . 

Benedictine 

Henry  II. 

Warwickshire 

Monmouth  .... 

Do. 

Henry  I. 

Monmouthshire 

Montacute   .... 

Cluniac 

Henry  I. 

Somersetshire 

Morfield      .... 

Benedictine 

Shropshire 

Motesfort     .... 

Augustine 

King  John 

Hampshire 

Mottenden  .... 

Trinity 

1124 

Kent 

Mountgraye      .    .    . 

Carthusian 

Yorkshire 

Mountjoy     .... 

Benedictine 

1264 

Norfolk 

Kanah 

Augustine 

1200 

Tipperary 

Neot*s(St.)      .    .    . 

Benedictine 

1113 

Huntingdonshire 

Nesseham    .... 

Do. 

King  John 

Durham 

Newark 

Augustine 

1121 

Surrey 

Newburgh   .... 

Do. 

1145 

Yorkshire 

Newent 

Benedictine 

Wm.  Conq. 

Gloucestershire 

Newington  Longayille 

Cluniac 

Henry  I. 

Buckinghamshire 

Newnham    .... 

Augustine 

Henry  II. 

Bedfordshire 

Newsham     .... 

Gilbertine 

1173 

Lincolnshire 

Newsted 

Augustine 

1170 

Nottinghamshire 

Newstede     .... 

GUbertme 

Henry  III. 

Lincolnshire 

Nocton 

Do. 

King  Stephen 

Do. 

Normannesbirch    .    . 

Cluniac 

1160 

Norfolk 

Northampton    .    .    . 

Do. 

1076 

Northamptonshire 

North  Femby  .    .    . 

Augustine 

Yorkshire 

North  Ormesby     .    . 

Gilbertine 

King  Stephen 

Lincolnshire 

Norton 

Aug^tine 

1330 

Cheshire 

NosteU 

Do. 

Henry  I. 

Yorkshire 

Nutley 

Do. 

1162 

Buckinghamshire 

Oegmild 

Benedictine 

1202 

Ireland 

Okebum 

Do. 

1149 

Wiltshire 

Old  Malton  .... 

Gilbertine 

1150 

Yorkshire 

Oyeton 

Do. 

King  John 

Do. 

Oyingham    .... 

Augustine 

Northumberland 

353 


• 

PRI 

PRIORIES. 

PRI 

-     NAME. 

ORDER. 

DATE. 

CODNTY. 

Panfeld 

Benedictine 

Wm.  Conq. 

Essex 

Pembroke    .    .    .    . 

Do. 

1098 

Pembrokeshire 

Penmon 

Do. 

1221 

Anglesea 

Peterson      .    .    .    . 

Augustine 

1200 

Norfolk 

PUle 

Benedictine 

1200 

Pembrokeshire 

Pilton 

t 

1200 

Devonshire 

Pinnortham .     .     .     . 

Benedictine 

Wm.  Conq. 

Lancashire 

Pintney 

Augustine 

Do. 

Norfolk 

Pittenweem.     .    .    . 

Do. 

Fifeshire 

Pluscardine  .     .     .     . 

VaUis  CauUnm 

1230 

Moray 

Plympton     .     .     .     . 

Augustine 

1121 

Devonshire 

Pontefract    .    .     .     . 

Cluniac 

Wm.  Rufus 

YcHtshire 

Porchester   ,    .    .    . 

Augustine 

1133 

Hampshire 

Port  Moack      .    .     . 

Do. 

Kinross-shire 

Poughley      .    .    .    . 

Do. 

1160 

Berkshire 

Priory  in  the  Wood   . 

Carthusian 

Richard  II. 

Lincolnshire 

PrittleweU   .    .    .    . 

Cluniac 

Essex 

Pulton 

Gilbertine 

Edward  III. 

WUtshire 

Pyneham      .    •    .    . 

Augustine 

1151 

Sussex 

Ramestede  .    .    .    . 

Benedictine 

Henry  II. 

Do. 

Ratlingcope.    .    .    . 

Augustine 

Shropshire 

Ravenston    .    .    .    . 

Do. 

Henry  III. 

Buckinghamahire 

Redholm      .    .    .    . 

Cistercian 

Henry  I. 

Yorkshire 

Restennote  .    .    .    . 

Augustine 

1296 

Forfmhire 

Rhudland     .    .    .    . 

Black  Friars 

1268 

Flintshire 

Rindelgros  .    .    .    . 

1124 

Perthshire 

Ripton 

Augustine   * 

1172 

Derbyshire 

Ronton 

Do. 

Henry  II. 

Staffordshire 

Rosneth 

Do. 

Dumbartonshire 

Roucester     .    .    .    . 

Do. 

1146 

Staffordshire 

RowadiU      .     .    .    . 

Do. 

Ross*shire 

Royston 

Do. 

Henry  II. 

Herefordshire 

Rumburgh   .     .     .     . 

Benedictine 

1064 

Suffolk 

Ryegate 

Augustine 

1200 

Surrey 

Sandford      .     .     .     . 

Do. 

1205 

Berkshire 

Sandleford    .     .     .     . 

Do. 

1114 

Do. 

Sandwell      .     .     .     . 

Benedictine 

Henry  II. 

Staffordshire 

Scokirke       .     .     .     . 

Augustine 

1114 

Yorkshire 

Sciirinoke    .     .     .    , 

Do. 

Ross-shire 

Selbume      .     .    .     . 

Do. 

1233 

Hampshire 

Sele 

Benedictine 

1076 

Sussex 

Sempringham    .     .     . 

Gilbertine 

1139 

Lincohisbire 

Shelbred      .    .    .     . 

Augustine 

Sussex 

Shelford 

Do. 

Henry  II. 

Nottinghamshire 

Sbenbum  (West)  .    . 

Benedictine 

Henry  I. 

Hampshire 

Shene      

Carthusian 

1444 

Surrev 

Shouldham  .     .     .     . 

Gilbertine 

Richard  I. 

Norfolk 

Sixhill 

Do. 

Lincolnshire 

Snape      

Benedictine 

1155 

Suffolk 

Snellesball   .     .     .    . 

Do. 

Henry  III. 

Buckinghamshire 

Soul's  Seat  .    .     .    . 

Premonstrant 

1296 

Kirkcudbrightshire 

Southwyke  .     .     .     . 

Augustine 

1133 

Hampshire 

Speatesbury      .     .     . 

Henry  I. 

Dorsetshire 

354 


PRI                                               PRIORIBS. 

PRI 

1 

XAMB. 

OBDBK. 

DATE. 

COUNTY. 

Spinney 

Augustine 

Heniy  III. 

Cambridgeshire 

Spinney 

Do. 

Edward  I. 

Do. 

Stanesgate    .... 

Cluniac 

1176 

Essex 

Stanley 

1146 

Gloucestershire 

Stanley  St.  Leonard   . 

Benedictine 

1146 

Do. 

Staverdale    .... 

Augustine 

1263 

Somersetshire 

St.  Andrew  .... 

Benedietine 

Ulster 

St.  Andrew  .... 

Cluniac 

1076 

Northamptonshire 

St.  Andrew  at  Yoik    . 

Sempring;. 

1200 

Yorkshire 

St.  Catherine    .    •    . 

Do. 

1148 

Lincoln 

St.  Clare 

Cluniac 

1291 

Caermarthenshire 

St.  Denys     .... 

Augustine 

1124 

Hampshire 

St.Dogmers     .    .    . 

Tyrone 

Wm.  Conq. 

Pembrokeshire 

St.  Faith,  at  Horsham 

1105 

Norfolk 

St.  Guthlac  .... 

Benedictine 

about  1000 

Herefordshire 

St.  James     .... 

Cluttiao 

1140 

Derby 

St.  James     .    .    «    . 

Do. 

1157 

Exeter 

St.  James     .... 

Benedictine 

1147 

Bristol 

St.  John  the  Bvan-  1 
gelist                   J 

Augustine 

1211 

Kilkenny 

St.  Julian     .... 

Do. 

1107 

Essex 

St.  Leonard .... 

1394 

Norwich 

St.  Leonard,  Stamford 

658 

Lincolnshire 

St.  Martin    .... 

Benedictine 

1146 

Yorkshire 

St.  Martin    .    •    •    . 

Do. 

640 

Dover 

St.  Mary's  Isle  .    .    . 

David  I. 

Kirkcudbrightshire 

St.  Maiy  Magdalen    . 

Do. 

1291 

Lincolnshire 

St.  Mary  Overy     .    • 

Augustine 

1106 

Surrey 

St.  Neot's     .... 

Benedictine 

850 

Huntingdonshire 

StOsith      .... 

Augustine 

635 

Essex 

StOswalde      .    .    . 

Do. 

909 

Gloucester 

Sts.  Peter  and  Paul,  1 
Ipswich                J 

Do. 

Henry  II. 

Suffblk                         1 

St.  Thomas  .     •    •    ■. 

Do. 

1172 

Dublin                          i 

St.  Thomas 

>    «    •     . 

Do. 

1180 

Stafford 

Stevesholm  < 

>    .     «    . 

Cluniac 

King  Stephen 

Norfolk 

Steyning .    , 

Benedictine 

Wm.  Conq. 

Sussex 

Stoke  Curry 

•     . 

Bo. 

Henry  n. 

Somersetshire 

Stone      .    , 

>    •     •    » 

Autdstine 

Henry  L 

Staffordshire 

Stoneley .     . 

Do? 

1180 

Huntingdonshire 

Strathfillan  . 

Do. 

Rob*.  Bruce 

Perthshire                     ; 

Studley   . 

Do. 

Henry  II. 

Warwickshire 

Sudbury .    , 

Benedictine 

1139 

Suffolk 

Swayesay 

Do. 

William  L 

Cambridgeshire            | 

Tandridge 

Augustine 

1308 

Surrey 

Taunton  .    < 

Do. 

Henry  I. 

Somersetshire 

Thetford 

Cluniac 

1103 

Norfolk 

Thetford 

Do. 

1114 

Norfolk 

Thoby     .     , 

Augustine 

1141 

Essex                            ! 

Thomham    . 

Do. 

King  Stephen 

Lincolnshire                 , 

Thorsling     . 

Do. 

Cambridgeshire 

Thremhale   . 

Do. 

Wm.  Conq. 

Essex 

Thurgarton  , 

Do. 

1130 

Nottinghamshire 

355 


PRI 


PRIORIES. 


PRI 


NAME. 

ORDER. 

DATE. 

COONTY-. 

Tickford 

Cluniac 

William  II. 

Buckinghamshire 

Tinmouth 

Benedictine 

633 

Northumberland 

Tiptree    .    . 

A.ugiistine 

Edward  I. 

Essex 

Toberglorie  . 

Do. 

Down 

Tooting  .     . 

Black  Monks 

Wm.  Conq. 

Surrey 

Torkesay 

Augustine 

King  John 

Lincolnshire 

Tortington   , 

Do. 

1376 

Sussex 

Tortington   . 

Do. 

ante  John 

Do. 

Totness    .     . 

Benedictine 

Wm.  Conq. 

Devonshire 

Trentham 

Augustine 

783 

Staffordshire 

Tristernagh  . 

Do. 

1217 

Westmeath 

Tukeley  . 

Henry  I. 

Essex 

Tunbridge    . 

Do. 

Henry  I. 

Kent 

Tunbridge    , 

Do. 

Richard  I. 

Surrey 

Tanstal   . 

Gilbertine 

King  Stephen 

Lincolnshire 

Tutbury  . 

Benedictine 

1080 

Staffordshire 

Tykeford 

Cluniac 

1291 

Buckinghamshire 

Tywardreth 

Benedictine 

1169 

Cornwall 

Twinham 

Augustine 

1150 

Hampshire 

Ulverscroft  , 

Do. 

Edward  II. 

Leicestershire 

Urquhart 

Benedictine 

David  1. 1225 

Moray 

Usk    .     .    . 

Do. 

1236 

Monmouthshire 

Vaudey   .    . 

Cistercian 

1147 

Lincolnshire 

WaUingford      .    . 

Benedictine 

WiUiam  I. 

Berkshire 

Walsingham      .    . 

Augustine 

1061 

Norfolk 

Walton  St.  Felix,  & 

c. . 

1105 

Suffolk 

Wanford      .    .    . 

Cluniac 

1160 

Do. 

Ware 

1081 

Hertfordshire 

Wareham     .    .    . 

Henry  I. 

Dorsetshire 

Warmington     .    . 

Benedictine 

Henry  I. 

Warwickshire 

Wartre    .... 

Augustine 

1132 

Yorkshire 

Warwick  (St.  Sepul 
chre)   .... 

•} 

Do. 

Henry  I. 

Warwickshire 

Watton   .... 

Gilbertine 

1150 

Yorkshire 

Wayburn      .    .    . 

Augustine 

Henry  II. 

Norfolk 

Weedon  Pinkney  . 

Benedictine 

Henry  I. 

Northamptonshire 

Welles     .... 

Gilbertine 

Richard  I. 

Cambridgeshire 

Wells      .... 

Benedictine 

Wra.  Conq. 

Norfolk 

Wenlock      .    .    . 

Cluniac 

Wm.  Conq. 

Shropshire 

Westacre      .    .    . 

Augustine 

Wm.  Rufns 

Norfolk 

Wetherall     .    .    . 

Benedictine 

about  1000 

Cumberland 

Weybridge  .    .    . 

Augustine 

Edward  I. 

Norfolk 

Whitshorn   .    .    . 

Premonstrant 

David  I. 

Kirkcudbrightshire 

Wilmington      .    . 

Benedictine 

Wm.Rufus 

Sussex 

Wingall  .... 

Lincolnshire 

Winge     .... 

Benedictine 

King  Stephen 

Buckinghamshire 

Withain  .... 

Carthusian 

1181 

Somersetshire 

Wolenchmere   .    . 

Augustine 

Henry  III. 

Sussex 

Wombridge       .    . 

Do. 

Henry  I. 

Shropshire 

Woodbridge      .    . 

Do. 

1200 

Suffolk 

W^oodhouse .    .    . 

Do. 

1250 

Shropshire 

Woodkirk     .     .     . 

Do. 

Henry  I. 

Yorkshire 

Wooton  Wa\ 

en 

Benedictine 

Henry  I. 

Warwickshire 

356 


:e»ri                  proportion  in  architecture.                pro 

KAME. 

ORDER. 

DATE. 

COUNTT. 

Worksop      .... 

Angustiae 

Henry  I. 

Nottinghamshire 

Wormegay  .... 

Do. 

1468 

Norfolk 

Wormeleye  .... 

Do. 

King  John 

Herefordshire 

Worspring   .... 

St.  Victor 

1210 

Somersetshire 

Wrangford  .... 

Claniac 

1160 

Sussex 

Wroxton      .... 

Augustine 

Henry  III. 

Oxfordshire 

Wymondsley     .    .     . 

Do. 

Henry  III. 

Hertfordshire 

Yarmoath    .... 

Benedictine 

1101 

Norfolk 

Prianif  in  geometns  a  body  or  soHd 
whose  two -thirds  are  any  plane 
figures  which  are  parallel,  equal, 
and  similai',  and  its  sides  paral- 
lograms 
Priam,  in  optics,  a  triangular  bar  of 
glass,  well  known  from  the  effect  it 
produces  on  a  ray  of  light  trans- 
mitted through  it :  this  effect  is  a 
decomposition  of  the  light  into  its 
component  emanations,  consisting 
of  the  three  primary  colours  and 
the  secondary  tints  arising  from 
i      their  intermixture,  which  together 
form  what    is  termed  the   «o2ar 
apectrum.    The  lensic  prism  is  a 
new  optical  glass,  in  which  the 
powers  of  the  lens,  and  prism  are 
combined. 
Pmon,an  edifice,  unfortunately  mostly 
of  large  dimensions,  for  the  con- 
finement  of  persons  warring  against 
society 
Profile^  the  outline  of  a  series  of 
mouldings,  or  of  any  other  parts, 
as  shown  by  a  section  through 
them 
PrqfUe  of  an  Order^  in  architecture, 
an  assemblage  and  arrangement  <rf 
essential    and    subservient   parts. 
That  profile  is  preferable  wherein 
the  parts  are  few,  varied,  and  fitly 
applied.  Some  member  should  pre- 
dominate in  each  division,  which  it 
should  appear  the  office  of  the 
other  parts  to  fortify,  support,  or 
shelter.  In  a  cornice  the  corona  is 
supported  by  modillions,  dentils, 
ovolos,  &c.,  and  sheltered  and  co- 
vered from  the  effects  of  the  wea- 
ther  by  its  cyma  or  cavetto. 
Prqi$i*tile,  in  mechanics,  a  body  put 

in  motion  by  an  external  force 
Prqjeetilett  in  mechanics,  that  branch 


which  considers  the  mass,  velocity, 
range,  &c.  of  a  heavy  body  pro- 
jected into  iroid  space  by  an  exter- 
nal force,  and  then  left  to  the  free 
action  of  gravity 

Projection,  in  geometry,  drawing,  &c., 
a  plan  or  delineation ;  in  chemistry, 
the  crisis  of  an  operation 

Projecture,  in  architecture,  the  out- 
jutting  or  prominence  which  the 
moulding  andmembersbave  beyond 
the  plane  of  a  wall  or  column 

Prolate,  in  geometry,  an  epithet  ap- 
plied to  a  spheroid  produced  by 
the  revolution  of  a  semi-ellipsis 
about  its  long  diameter 

Pronaos,  the  area  immediately  before 
a  temple.  The  term  is  often  used 
for  the  portico  in  front  of  a  build- 
ing. The  posticus  in  one  front 
corresponds  to  the  pronaos  in  the 
other :  in  some  temples,  the  cella 
was  entered  through  both.  The 
generality  of  Grecian  temples  had 
two  approaches. 

Proportion,  in  architecture,  the  mag- 
nitude of  one  part  as  compared 
with  some  other.  The  term  *  pro- 
portion'  is  used  absolutely  in  the 
sense  of '  good  proportion,'  although 
every  thing  that  has  shape  has 
proportions  of  some  kind  or  other. 
The  subject  of  proportion  has  been 
greatly  mystified  by  vmters,  who 
haye  laid  dovni  certain  fixed  pro- 
portions as  the  best  of  all  on  every 
occasion,  and  as  the  ne  plits  ultra 
of  artistic  taste.  But  fixed  propor- 
tions can  be  followed  mechanically 
by  every  one  alike ;  whereas  it  re- 
quires ability  to  deviate  successfully 
from  routine  measurement,  and 
apply  the  poco  pia  or  thepoco  meno 
as  the  particular  occasion  or  the 


357 


q5 


PRO 


PROPYLiEA. 


PRO 


particular  effect  aimed  at  may  re- 
quire— at  least,  justify.  It  is  the 
eye  that  takes  cognizance  of  pro- 
portions ;  and  the  architect's  own 
eye  ought  to  be  quite  as  correct  as 
that  of  other  people. 

Proportion^  that  branch  of  mathema- 
tical science  which  defines  the  ra- 
tio of  numbers  or  quantities  to  each 
other 

Proportiofu  of  room*  should  be  suited 
to  the  purposes  for  which  they  are 
used :  all  figures,  from  the  square 
to  one  and  a  half  the  breadth  of 
the  room,  may  be  employed  for  the 
plan.  Some  have  extended  the 
plan  to  a  double  square.  Galleries 
may  be  from  five  to  eight  times 
their  breadth.  The  height,  if  with 
fiat  ceilings,  is  not  required  to  be 
so  great  as  in  those  that  are  coved. 
The  height  of  square  apartments 
should  not  exceed  five-sixths  the 
side  of  the  square,  nor  be  less  than 
four-fifths ;  but  in  rooms  that  are 
oblong,  the  height  ought  to  be 
equal  to  the  breadth.  The  height 
of  square  rooms  that  are  coved 
should  be  equal  to  one  of  the  sides 
of  the  square;  but  coved  oblong 
rooms  require  a  height  equal  to  the 
breadth,  added  to  one-fifth,  one- 
quarter,  or,  at  most,  one-third  of 
the  difference  between  their  length 
and  breadth.  The  height  of  ^- 
leries  should  be  from  one  and  three- 
fifths,  at  most,  to  one  and  one-third, 
at  least,  of  their  breadth.  Cornices 
and  dressings  in  the  interior  of 
houses  are  always  to  be  kept  more 
delicate  than  those  on  the  out- 
side. 

Prqpykfunti  in  Greek  architecture, 
the  porch  of  a  temple  or  great  hall 

PropykNt :  the  entrance  to  a  Greek 
temple,  a  sacred  enclosure,  con- 
sisted of  a  gateway  fianked  by 
buildings,  whence  the  plural  of  the 
word.  The  Egyptian  temples  gene- 
rally had  magnificent  propylaea,  con- 
sisting of  a  pair  of  oblong  truncated 
pyramids  of  solid  masonry,  the  faces 
of  which  were  sculptured  with  hiero- 
glyphics.   The  word,  however,  is 


generally  used  to  signify  the  en- 
trance to  the  acropolis  of  Athens, 
which  veas  the  last  completed  of 
the   great  works   of  architecture 
executed  under  the  administration 
of  Pericles.    Pausanias  relates  that 
**  there  is  only  one  entrance  to  the 
acropolis,    it  being  in   every  re- 
maining part  of  its  circuit  a  preci- 
pice, and  fortified  with  strong  viralls. 
This  entrance  was  fronted  by  a 
magnificent  building,    called   the 
propylaea,  covered  with  rooft  of 
white  marble,  which  surpassed  for 
beauty,  and  the  dimensions  of  the 
marble,  all  that  he  had  before  seen." 
Thebuildingwas commenced  during 
the  administration  of  Pericles,  and 
finished  in  five  years,   Mnesieles 
being  the  architect,  at  the  expense 
of  2012  talents,  or  neariy  X464,000 
sterling.    There  were  five  gates  to 
the  propylaea,  and  before  it  stood 
two  lofty  piers,  on  each  of  which 
was  placed  an  equestrian  statue, 
supposed  to  be  the  sons  of  Xeno- 
phon.    On  the  right  of  the  pro- 
pylaea was  the  temple  of  Victory 
without  wings,  whence  is  a  pro- 
spect of  the  sea;  and  from  this  place 
it  was  said  that  iEgeus  threw  him- 
self down  headlong,  and  died.    On 
the  left  of  the  propylaea  was  an 
edifice  adorned  with  paintings,  the 
work  of  Polygnotus,  of  which,  says 
Pausanias,  though  some  vrere  ef- 
faced by  time,  there  still  remained 
those  of  Diomedes  and  Ulysses, 
the  one  bearing  off  the  bow  and 
arrows  of  Philoctetes  from  Lemnos, 
the  other,    the   Palladium    from 
Troy.    There  were  those  also  of 
Orestes  slaying  .£gisthus,  and  Py- 
lades  encountering  the  sons  of  Nau- 
plius,  who  had  come  to  succour 
i£gisthus;    Polyxena,  at  the    se- 
pulchre of  Achilles,  about  to  be  sa- 
crifioed,and  Ulysses  addressinghim- 
self  toNausicaa  and  her  maidens,  as 
described  by  Homer.  Several  other 
pictures   in  the   same  place   are 
described   by   Pausanias.      These 
three  contiguous  buildings  origi- 
nally formed  one  front,  bccupjring 


358 


PRO 


PULLEY. 


PUL 


the  ^rhole  breadth  of  the  rock  from 
side    to  side,  at  its  western  end, 
so  that  the  only  admission  into  the 
acropolis  was  through  the  middle 
building,  the  five  gates  of  which 
are  still  remaining,  and  prove  it  to 
have  been  the  propylaea.   It  may  be 
supposed  that  the  Hermes  Propy- 
lasus  was  here  placed,  and  perhaps 
the  Graces,  a  piece  of  sculpture  by 
the  hand  of  Socrates,  in  which  that 
celebrated  philosopher,  deriating 
from  the  practice  of  the  sculptors 
who  preceded  hun,  had  represented 
them  not  naked  but  clothed.    Other 
sculptors  are  also  mentioned  by 
Pausanias  who  seem  to  have  deco- 
rated this  stately  entrance. 
Proseem'sfM,  the  area  in  front  of  the 
scene  of  a  theatre,  which  was  per- 
ceived when  the  pulpitum  was  re- 
moved, and  when  it  u  probable  the 
temporary  scenes  were  taken  away 
in  order  to  exhibit  the  front  of  the 
permanent  scene 
Prottyie,  s  temple  which  has  a  por- 
tico in  oae  front,  consisting  of  in- 
auUnted  columns  with  their  entabla- 
tures and  frtttigittm*     When  the 
temple  had  a  portico  in  both  fronts, 
it  was  termed  amphi-prostyle,  or 
prostyle  in  all  parts. 
PrQtraetWj  in  surveying  and  trigo- 
nometry, an  instrument  by  which 
ang^  taken  in  the  field  with  a 
theodilite^drcumferentor  are  repre- 
tented  on  p^iper 
Pnm,  in  navigation,  the  head  or  fore- 
part of  a  sUp,  in  opposition  to  the 
poop  or  stern 
PniMurn  Bbi/B,  otherwise  called  Ber- 
lin blue,  Parisian  blue,  Prussiate  of 
iron,  cyanide  of  iron,  or,  in  lan- 
guage more  pedantically  chemical, 
per-feno-cyanate    of    iron,   with 
alnraine,  &c,  is  rather  a  modem 
pigment,  produced  by  the  com- 
bination of  the  prussic  or  hydro- 
cyanic acid,  iron,  and  alumina.    It 
is  of  a  deep  and  powerful  blue 
cotonr,  of  vast  body  and  consider- 
able transpareney,  and  UmxA  tints 
of  mnch  beauty  vrith  white-lead, 
though  they  are  by  no  means  equal 

359 


in  purity  and  brilliancy  to  those  of 
cobalt  or  ultramarine,  nor  have 
they  the  perfect  durability  of  the 
latter. 

Pnunan  Brown  is  a  preparation  of 
Prussian  blue  from  which  the  blue 
colouring  principle  has  been  ex- 
pelled by  fire,  or  extracted  by  an 
alkatine  ley :  it  is  an  orange  brown, 
of  the  nature  and  properties  of 
Sienna  earth,  and  dries  wdl  in 
oU 

Pruuitm  Green.  The  pigment  cele- 
brated under  this  name  is  an  im- 
perfect prussiate  of  iron,  or  Prus- 
sian blue,  in  which  the  yellow 
oxide  of  iron  superabounds,  or  to 
which  yellow  tincture  of  French 
berries  has  been  added,  but  is  not 
in  any  respect  superior  as  a  pig- 
ment to  the  compounds  of  Prussian 
blue  and  yellow  ochre.  A  better 
sort  of  Prussian  green  is  formed 
by  precipitating  the  prussiate  of 
potash  with  nitrate  of  cobalt. 

Pruuiate  of  Copper  differs  chemically 
from  Prussian  blue  only  in  having 
copper  instead  of  iron  for  its  basis. 
It  varies  in  colour  from  russet  to 
brown,  is  transparent  and  deep, 
but  being  very  liable  to  change  in 
colour  by  the  action  of  light  or  by 
other  pigments,  it  has  ^n  very 
little  employed  by  artists 

Pryant  in  mining,  that  which  ii  pro- 
ductive of  ore,  but  does  not  break 
in  large  stones,  but  only  in  pebbles 
with  a  mixture  of  clay 

Peemdo^ipteralf  a  temple  which  has 
a  single  range  of  columns  in  the 
flanks,  at  the  same  distanoe  from 
the  walls  of  the  eella  as  though 
the  temple  had  been  dipteral 

Pteroma^  the  spaces  between  the 
walls  of  the  cella  of  a  temple  and 
the  columns  of  a  peristyle;  called 
also  ambulatio 

PuddUng,  in  metallurgy,  a  process  in 
the  r^ning  of  iron  which  consists 
in  stirring  it  actively  about 

PuUe^f  one  of  the  six  mechanical 
powers.  The  puUey  is  a  small 
wheel  turning  on  an  axis,  with  a 
rope  or  chain  passing  over  it.  The 


PUL 


circumference  is  generally  grooyed 
to  receive  the  rope,  which  is  at- 
tached on  the  one  end  to  the  moy- 
ing  power,  and  on  the  other  to  the 
resisting  force.  Pulleys  are  of  two 
kinds — fixed  and  moveable.  The 
fixed  pulley  gives  no  mechanical 
advantage,  but  is  of  great  utility  in 
altering  the  direction  in  which  it 
may  be  applied.  The  moveable,  on 
the  contrary,  doubles  the  power, 
which  may  be  increased  in  any 
ratio  by  adding  to  the  number  of 
pulleys.  In  a  combination  of 
pulleys,  the  advantage,  however, 
is  greatly  diminished  by  the  fric- 
tion of  the  axles  and  of  the  ropes. 
Too  complex  a  combination  there- 
fore would  not  be  of  service,  as  the 
friction  would  be  increased  without 
a  proportional  advantage,  and  from 
the  complexity  of  the  machine 
would  be^more  liable  to  be  put  out 
of  order.* 

Pulpit,  an  elevated  stage  or  desk 
from  which  sermons  are  delivered. 
(For  beautiful  examples,  see  Mr. 
Parker's  *  Glossary  of  Architecture,' 
and  the  'Papers  on  Architecture/ 
4  vols.  4  to.) 

Pulpitum,  the  wooden  stage  of  the 
theatre  upon  which  the  mimic  as 
well  as  dramatic  exhibitions  of  the 
Romans  were  represented.  In  the 
Greek  theatre,  the  pulpitum  was 
used  only  by  the  histriones,  or 
performers  in  the  drama,  and  was 
probably  removed  before  the 
amusements  of  the  orchestra  were 
exhibited. 

Pulvinated.  A  frieze  whose  face  is 
convex  instead  of  plain  is  said  to 
be  pulvinated,  from  its  supposed 
resemblance  to  the  side  of  a 
cushion,  which  swells  out  when 
pressed  upon. 

Pump,  an  engine  for  raising  liquids, 
made  in  various  forms,  of  more  or 
less  complexity  of  parts  and  effec- 
tiveness of  action,  depending  in  its 
simplest  form  tpon  the  external 

s.  pressure  of  the  air  on  the  surface  of 
the  water,  and  in  other  forms  deriv- 
ing its  power  from  the  abstraction  of 


PUMP.  PUM 

the  air  vnthin  the  tube  or  barreL 
The  simplest  form  of  pump  is  that 
of  the  common  lift-pump,  which 
consists  of  a  straight  tube  with  two 
valves,  one  of  which  is  fitted  to  the 
lower  end  of  the  tube,  and  the  other 
is  made  to  slide  air-tight  in  the 
cavity  of  the  tube  or  barrel.     Both 
of  these  valves  are  adapted  to  open 
upwards  only,  and  thus  the  water 
is  admitted  and  lifted  from  the 
lower  part  of  the  tube  to  the  dis- 
charge aperture  above.    This  pomp 
acts  by  the  pressure  of  the  atmo- 
sphere upon  the  external  body  of 
water  from  which  the   supply  is 
raised,  but  by  the  forcing-pump 
water  may  be  raised  above  the  level 
to  which  it  is  driven  by  the  pressure 
of  the  atmosphere.     The  forcing- 
pump  consists  of  a  barrel  fitt^ 
vnth  a  solid  piston  or  forcer,  the 
barrel  being  also  pro\ided  with  a 
branch  forcing-pipe.     The  lower 
part  of  the  barrel  and  the  branch 
pipe  are  each  fitted  vnth  a  valve 
opening  upwards,  and  by  repeated 
strokes  of  the  piston,  the  pressure 
of  the  air  from  above  being  removed, 
the  fluid  is  brought  up  to  fill  the 
space  between  the  two  valves,  and 
being  prevented  from  returning  by 
the  lower  valve,  it  passes  through 
the  upper  valve  of  the  branch  pipe 
into  a  capacious  upper  vessel,  and 
there  accumulating,  may  be  ejected 
in  a  constant  instead  of  intermittent 
stream.  The  lift-pump,  being  simple 
and  economical  in  construction,  is 
well  fitted  for  extensive  works  in 
which  the  quantity  of  virater  to  be 
raised  is  considerable,  and  is  there- 
fore usually  employed  in  works  for 
supplying^  water  for  towns.     The 
pumps  used  at  the  Metropohtan 
and    other  water -works    are    of 
great  size,  and  deliver  immense 
volumes  of  water  at  each  stroke. 
Those    used  at  Haarlem  are  63 
*  inches  in  diameter,  and  the  pistons 
have  a  stroke  of  10  feet  in  length. 
Ilach  pump  delivers  6  tons  of  water 
at  each  stroke.  Pumps  of  this  mag- 
nitude are  worked  by  water  or  steam 


PUM 


PUMP.  PUM 


power.     Those  at  Haarlem,  eleven 
in  number,  are  worked  simultane- 
ously by  a  steam  engine,  having 
two  steam  cylinders,  one  within  the 
other,  the  larger  being  12  and  the 
smaller  7  feet  in  diameter,  with  a 
stroke  of  10ft.  (See  Forcmg-Punqf,) 
Pump.     Mr.    Appold's    centrifugal 
pump  for  draining  marshes,  and 
for  other  purposes,  will  discharge 
10  gallons  of  water  per  minute, 
and  is  only  1  inch  diameter :  one 
of  the  same  shape,  12  inches  dia- 
meter, will  discharge  at  the  same 
speed  of  the  outside  circumference, 
or  1^  the  number  of  revolutions, 
1440  gallons  per  minute,  being  ac- 
cording to  the  square  of  the  dia- 
meter, and  not  according  to  the 
cubic  contents.    From  various  ex- 
periments, it  has  been  found  that 
the  larger  model  with  the  curved 
vanes  does  the  most  duty,  on  ac- 
count of  its  receiving  and  delivering 
the  water  more  obliquely:  it  will 
discharge  1800  gallons  per  minute, 
with  607  revolutions,  but  does  the 
most  duty  at  535  revolutions,  dis- 
charging 1400  gallons;  therefore, 
if  a  pump  1  inch  diameter  raise  10 
gallons,  and  another  1  foot  dia- 
meter 1440  gallons,  it  follows  that 

one 

gals.permin. 

10  feet  diameter,  of  the 

best  shape,  will  pump  140,000 
20  ditto,  ditto  .  .  .  560,000 
40  ditto,    ditto  .     .    .  2,240,000 

To  do  the  above  duty,  the  cir- 
cumference of  the  20-feet  pump 
would  be  required  to  travel  560 
yards  per  minute,  which  would  be 
only  53^  revolutions,  and  the  40- 
feet  26f . 

From  the  results  of  various  ex- 
periments, it  has  been  found  that 
the  loss  of  power  would  not  be 
more  than  25  per  cent.  It  will  be 
observed,  the  centrifugal  force  is 
not  so  much  in  the  large  diameter, 
on  account  of  the  water  moving 
more  in  a  straight  line ;  but  that  is 
compensated  for  by  the  force  being 

361 


applied  to  a  greater  depth  of  water, 
being  10  feet  in  the  40-feet,  and 
only  3  inches  in  the  1-foot. 

ft.  high. 
159  revolutions,  with  the  1- 
foot,  will  raise  the  water, 
without  discharging  any,     1 

318  revolutions 4 

636  ditto 16 

1272  ditto .64 

The  highest  elevation  to  which 
the  water  has  been  raised  with  the 
1-foot  pump,  is  67  feet  8  inches, 
with  1322  revolutions  per  minute, 
being  less  than  the  calculated 
height,  which  may  be  accounted 
for  by  leakage  with  the  extra 
strain. 

While  the  1-foot  pump  is  raising 
8  tons  of  water  5  feet  6  inches  high 
per  minute,  there  is  no  greater 
strain  on  any  part  of  the  pump 
than  160  lbs.  on  the  6-inch  drum, 
which  is  equal  to  a  leverage  of  3 
inches.  (See  the  results  of  various 
experiments  in  the  Table  on  the 
the  next  page.)  It  will  pass  almost 
any  thing  that  is  small  enough  to 
go  through,  there  being  no  valves. 
A  quantity  of  nut-galls  (about  ^  a 
gallon)  were  thrown  into  the  1-foot 
pump  all  at  once,  when  it  was  at 
full  speed,  and  they  passed  through 
without  breaking  one. 

Dimensiona  of  the  Pump. 

Diameter 1  foot. 

Width 3  inches. 

Contents I  gallon. 


PUM 


PUNCHING  MACHINE. 


PUN 


Table  of  Mean  Results  of  various  Experiments  with  Mr,  Appold^s 

Centrifugal  Pump, 


No.  of 

revolutions 

per  minute 

of  6-inch 

drum  and 

pump. 


400 
412 
427 
440 
453 
474 
481 
495 
518 
535 
563 
580 
595 
607 


Number  of 

gallons  Tftiaed 

5  feet  6  inches 

high  per 

minute. 


Equivalent  in 
lbs.  raised  1  foot 
high  per  minute. 


500 

600 

700 

800 

900 

1000 

1100 

1200 

1300 

1400 

1500 

1600 

1700 

1800 


27,500 
33,000 
38,500 
44,000 
49,500 
55,000 
60,500 
66,000 
71,500 
77,000 
82,500 
88,000 
93,500 
99,000 


Strain  in  lbs. 
on  a  drum  of 
4  ft.  diameter 
driving  one  of 
6  in.  diameter, 
as  measured 

by  a 
dynamometer. 


Equivalent 

stnunon  the 

steam  engine, 

rated  in  lbs., 

raised  1  foot  high 

per  minute. 


74 

80 

87 

94 

100 

106 

113 

118 

121 

126 

134 

138 

142 

150 


44,400 

49,440 

55,723 

62,010 

67,950 

75,366 

81,479 

87,615 

94,017 

101,115 

113,163 

120,060 

126,733 

136,575 


of  work  done 

compared 

with  power 


61-7 

66-7 

69- 

70-9 

72-8 

72-9 

74*2 

75-3 

76- 

761 

72-9 

73-3 

73*6 

72-5 


Pumpf  marine,  a  machine  to  draw 
inrater  out  of  a  ship's  hold 

Pun^jMshain,  This  consists  of  a  long 
chain  with  yalves  at  proper  dis- 
tances, working  on  two  wheels,  one 
above  and  one  below,  and  passing 
down  through  one  wooden  tube  and 
returning  upwards  by  another. 

Pump-cistern^  to  reoei?e  the  water 
from  the  pumps 

Pump-daleSt  pipes  to  convey  water 
from  the  pump-cisterns  through  the 
ship's  sides 

Pumping  engine^  a  steam  engine  for 
raising  water 

Punchy  in  mining,  a  piece  of  timber 
used  as  a  support  for  a  roof 

Punch,  a  tool  for  making  an  im- 
pression, or  for  forcing  a  hole 
through  a  plate 

Puncheonf  a  measure  of  liquids  con- 
taining eighty.four  gallons 

PuneheorUf  small  upright  timbers  in 
wooden  partitions,  now  usually 
called  studs  or  quarters ;  they  are 
placed  upright  between  two  posts 
whose  beimng  is  too  great,  serving, 

362 


together  with  them,  to  sustain  some 
large  weight 
Pw/tchrngMnd  Plate'Cutting  Machine, 
The  operation  of  pnnchiqg  holes 
through  thick  metal  plates  requires 
machinery  of  a  very  massive  de- 
scription, on  account  of  the  violent 
strains  to  which  it  is  subjected ; 
and  the  power  of  these  machines 
being  exerted  only  at  intervals,  it 
is  necessary  to  apply  some  means  of 
rendering  the  motion  tolerably  uni- 
form, and  thereby  diminishing  as 
much  as  possible  the  violence  of 
the  strain.     This  is   effected  by 
Betting  in  motion  a  heavy  iy- wheel, 
80  that  the  power  expended  in 
giving  a  certain  velocity  to  the 
wheel  shall  be  stored  up  till  the 
operation  of  punching  oommenoes, 
which  tends  to  retard  the  motion : 
the    accumulated  power   in    the 
wheel  will  then  tend  to  maintain 
the  speed,  and  thus  an  appfonma- 
tion  to  uaifonn  motion  ia  obtained. 
The  machine  consists  of  a  strong 
finme,  at  the  front  of  which  is  a 


PUN 


PURPLE  LAKE. 


PUR 


broad  slide,  moved  vertically  up 
and  down  by  an  eccentric  fixed  on 
the  end  of  a  shaft  passing  length- 
wise through  the  frame:  on  this 
shaft  there  is  a  large  wheel,  which 
receives  motion  from  a  pinion  on 
another  shaft  carrying  the  fly- 
wheel and  driving-pulleys.  The 
punches,  the  number  of  which 
varies  according  to  the  size  of  the 
holes,  are  fixed  in  the  lower  end  of 
the  vertical  sliding  piece,  and  im- 
mediately under  them  is  fixed  a 
piece  of  steel,  called  the  dies, 
which  has  holes  in  it  to  correspond 
with  the  punches.  The  plate  in 
which  holes  are  to  be  punched  is 
fastened  upon  a  travelling  table  in 
front  of  the  machine;  and  the  slide 
being  up,  and  the  surface  of  the 
table  level  with  that  of  the  dies, 
the  part  where  the  holes  are  to  be 
punched  is  placed  between  the 
punches  and  the  dies,  so  that  when 
the  machine  is  set  in  motion,  the 
punches  are  forced  through  the 
plate  by  the  action  of  the  eccentric, 
and  the  pieces  driven  out  fall 
through  the  holes  in  the  dies: 
after  the  punches  have  risen  above 
the  surface  of  the  plate,  the  tra- 
velling table  is  aet  forward  to  the 
required  distance  by  self-acting 
apparatus,  and  the  operation  is  re- 
peated by  the  machine  till  the  re- 
quired number  of  holes  has  been 
punched. 

The  plate-cutting  apparatus  con- 
sists of  two  steel  plates,  forming  a 
pair  of  shears;  the  lower  plate  is 
fixed  on  the  frame  of  the  machine, 
and  the  upper  one  is  attached  to  a 
slide,  as  in  the  case  of  the  punches, 
acting  in  a  umilar  manner.  The 
shears  are  moved  by  the  same 
shaft  as  the  punches,  and  act  while 
the  punches  are  being  raised: 
sometimes  they  are  placed  at  the 
top  of  the  punching  slide. 

Puntf  in  navigation,  a  sort  of  oblong, 
flat-bottomed,  small  boat,  with  a 
square  head  and  stem 

Pur^eck^tme^  an  alkaline  sandstone, 
harsh  and  rough,  of  a  disagreeable 

363  ~~~ 


ash  colour,  very  heavy,  and  mo- 
derately hard ;  of  a  texture  not  very 
compact,  but  somewhat  porous,  and 
composed  of  an  angular  grit,  ce- 
mented together  by  an  earthy  spar. 
It  cuts  freely,  and  with  a  tolerably 
even  or  smooth  surface,  but  will  not 
take  a  polish :  it  is  used  principally 
in  London.  The  quarries  are  in 
the  island  of  Purbeck,  Dorsetshire. 

PurHnSj  in  carpentry,  those  pieces  of 
timber  that  lie  across  the  rafters  on 
the  inside,  to  keep  them  from 
sinking  in  the  middle 

Purplct  the  third  and  last  of  the 
secondary  colours,  is  composed  of 
red  and  blue,  in  the  proportions  of 
five  of  the  former  to  eight  of  the 
latter,  which  constitutes  a  perfect 
purple,  or  one  of  such  a  hue  as  will 
neutralize  and  best  contrast  a  per- 
fect yellow  in  the  proportion  of 
thirteen  to  three  of  surface  or  in- 
tensity. It  forms,  when  mixed 
with  its  co-secondary  colour,  green, 
the  tertiary  colour  olive,  and 
when  mixed  with  the  remaining 
secondary  orange,  it  constitutes  Jfche 
tertiary  colour  russet. 

Purple  Black  is  a  preparation  of 
madder,  of  a  deep  purple  hue,  ap- 
proaching to  black ;  its  tints,  with 
white-lead,  are  of  a  purple  colour. 
It  is  very  transparent  and  power- 
ful, glazes  and  dries  well  in  oil,  and 
is  a  durable  and  eligible  pigment, 
belonging  perhaps  to  the  semi- 
neutral  class  of  marrone. 

Purple  Ijoke.  The  best  purple  lake, 
so  called,  is  prepared  from  cochi- 
neal, and  is  of  a  rich  and  powerful 
colour,  inclined  to  crimson.  Its 
character  as  a  pigment  is  that  of  a 
cochineal  lake,  already  described. 
It  is  fugitive  both  in  glazing  and 
tint,  but,  used  in  considerable  body, 
as  in  the  shadows  of  draperies,  &c., 
it  will  last  under  favourable  cir- 
cumstances a  long  time.  Lao  lake 
resembles  it  in  colour,  and  may 
supply  its  place  more  durably,  al- 
though not  perfectly  so. 

Purple  Ochre,  or  Mineral  Purple,  is  a 
dark  ochre,  a  native  of  the  forest  of 


PUR 


PYRAMID. 


PYR 


1 


Dean,  in  Gloucestershire.  It  is  of 
a  murrey  or  chocolate  colour,  and 
forms  cool  tints  of  a  purple  hue, 
with  white.  It  is  of  a  similar 
body  and  opacity,  with  darker 
colour  than  Indian  red,  which  has 
also  been  classed  among  purples, 
but  in  all  other  respects  it  re- 
sembles that  pigment.  It  may  be 
prepared  artificially,  and  some  na- 
tural red  ochres  bum  to  this  colour, 
which  has  been  employed  under 
the  denomination  of  violet  de  mar. 

Purple  wood  is  from  the  Brazils,  im- 
ported in  logs  from  8  to  12  inches 
square,  and  8  to  10  feet  long,  prin- 
cipally used  for  ramrods,  buhl- 
work,  marquetry,  and  turnery 

PurseTf  the  cashier  or  paymaster  of 
mines;  also  the  paymaster  of  a 
ship 

Pursuivant f  in  heraldry,  a  messenger 
who  formerly  attended  the  king  in 
his  wars,  or  at  the  council  table, 
and  ultimately  became  herald 

Putealf  the  enclosure  surrounding 
the  opening  of  a  well,  to  protect 
persons  from  falling  into  it.  It 
was  either  round  or  square,  from 
3  to  4  feet  high.  There  is  a  round 
one  in  the  British  Museum,  made 
of  marble. 

Putlogs  or  PutloeiSf  in  building,  are 
short  pieces  of  timber  about  7  feet 
long,  used  in  building  scaffolds. 
They  lie  at  right  angles  to  the  wall, 
with  one  of  their  ends  resting  upon 
it,  and  the  other  upon  the  poles 
which  lie  parallel  to  the  side  of  the 
wall  of  the  building. 

Putlog-holeSi  small  holes  left  in  walls 
for  the  u&e  of  the  workmen  in 
erecting  scaffolding 

Putty,  in  the  arts,  a  kind  of  paste 
used  by  glaziers,  composed  of 
whiting  and  linseed  oil  (with  or 
without  white-lead),  beaten  toge- 
ther to  the  consistence  of  a  tough 
dough 

PuzzolanOf  or  Pouzzolano,  in  mine- 
ralogy, a  volcanic  sand  of  a  violet 
red  colour,  (the  puhis  Puteoli  of 
Pliny,)  brought  from  Italy,  which 
forms  a  cement  that  hardens  under 

364 


water.  It  appears  to  be  a  species 
of  argillaceous  earth  that  probably 
has  been  calcined  and  then  ejected 
from  a  volcano.  Its  constituents 
are  silex,  alumina,  oxide  of  iron, 
and  a  little  lime.  It  was  first  dug 
out  of  the  earth  by  the  Romans 
near  the  town  of  Pouzzol,  not  far 
firom  Vesuvius.  The  environs  of 
Rome  furnish  it  equally.  It  has 
been  ibund  in  France  in  the  ex- 
tinct volcanoes  of  Yivares.  There 
are  a  few  regions  exposed  to  ig- 
neous agency  which  are  destitute 
of  it,  but  it  presents  itself  under 
very  different  physical  appear- 
ances, —  sometimes  pulverulent, 
sometimes  in  coarse  grains,  often 
in  slag,  pumice,  tufa,  &c.  Its 
colour,  which  is  generally  brovni, 
passes  to  yellow,  gray,  and  black. 
The  only  preparation  this  n[iateiial 
undergoes  previous  to  use  is  that 
of  pounding,  or  grinding  and  sift- 
ing, whereby  it  is  reduced  to  pow- 
der, in  which  state  it  is  beaten  to 
a  proper  consistency  v^th  a  due 
proportion  of  lime.  Artificial 
pouzzolano  is  also  much  used,  and 
is  produced  by  pulverizing  the 
clay,  the  psammite,  or  the  arene, 
which  is  soluted,  and  the  strewing 
a  layer  of  it,  about  four-tenths  of 
an  inch,  on  a  plate  of  iron,  heated 
to  a  point  between  a  cherry-red 
and  forging  heat.  It  is  left  till  it 
be  raised  to  the  same  degree,  for 
a  space  of  time  which  varies,  for 
each  kind  of  material,  from  five  to 
twenty  minutes.  It  must  be  con- 
tinually stirred  with  a  small  rod, 
in  order  that  the  whole  of  the  par- 
ticles may  be  uniformly  calcined. 

Pycnostykf  that  arrangement  of 
Greek  or  Roman  columns,  in 
which  the  intercolumniations  are 
equal  to  one  diameter  and  a  half 
of  the  lower  part  of  the  shaft 

Pyramidy  in  geometry,  is  a  solid 
figure  whose  base  is  a  polygon, 
and  whose  sides  are  plain  triangles, 
their  several  points  meeting  in  one 
.  Pyrites,  in  mineralogy,  a  name  given 
to    certain  metallic  ores  contain- 


PYR 


QUARTER-GALLERY. 


QUA 


ing  a  large  portion  of  sulphur; 
native  compounds  of  sulphur  with 
different  metals,  and  more  espe- 
cially with  iron.  The  term  is 
derived  from  the  use  to  which  the 
stone  was  formerly  applied,  that  of 
obtaining  sparks  by  percussion,  an 
application  of  pyrites  mentioned 
by  Pliny. 

PyriteSf  Ck^tper,  in  mineralogy,  a 
combination  (sulphuret)  of  copper 
and  sulphur,  being  the  most  com- 
mon ore  of  copper 

Pyrites,  Iron,  in  mineralogy,  a  com- 
bination (sulphuret)  of  iron  and 
sulphur,  one  of  the  most  abundant 
minerals  in  nature 

Pyrometer,  in  chemistry,  an  instru- 


ment for  measuring  very  high  tem- 
peratures, depending  on  the  uni- 
form and  permanent  contraction 
of  pure  clay 

Pyrometer,  a  contrivance  for  ascer- 
taining the  temperature  of  the 
flues  of  boilers,  by  fixing  an  iron 
wire  at  the  back  of  the  flue,  and 
connecting  it  to  a  lever  in  front  of 
the  boiler,  which  indicates  the  de- 
gree of  expansion  and  consequently 
the  temperature 

Pyx,  Pix,  a  tabernacle  or  shrine,  a 
depository  for  the  Host,  or  con- 
secrated wafer,  used  in  Roman 
ceremonies.     (See  Theoreea,) 

Pyx,  in  navigation,  the  box  in  which 
the  nautical  compass  is  suspended 


QUA 

QuAD&A)  in  architecture,  a  name 
given  by  Vitruvius  to  the  square 
piece,  commonly  called  the  sode, 
used  to  support  the  pedestals 
of  statues,  vases,  and  other  orna- 
ments 

Quadra,  the  bands  or  fillets  of  the 
Ionic  base,  between  which  the 
scotia  or  hollow  occurs;  also  the 
plinth,  or  lower  members  of  the 
podium 

Quadrangle,  a  figure  having  fourangles 
and  four  sides 

Quadrant,  the  fourth  part  of  a  circle, 
being  bounded  by  two  radii  per- 
pendicular to  each  other,  and  a 
quarter  of  the  drcumference,  or 
90  degrees 

Quadrature,  the  finding  a  square  equal 
in  area  to  another  figure 

Quadriforee,  folding  -  doors  whose 
height  was  divided  into  two. 
Folding-doors  which  opened  in 
one  height  were  termed  fores  vol- 
vata,  or  vaha,  Vitruvius  directed 
the  doorways  to  be  made  wider 
when  these  were  used,  and  the 
height  to  be  increased  when  the 
folding-doors  were  divided  in 
height.  The  biforee  of  Vitruvius 
were  two  single  doors. 

365 


QUA 

Quarry,  a  place  underground  from 
whence  are  taken  marble,  freestone, 
slate,  limestone,  and  other  stones 
proper  for  building  and  paving 

Quarry,  a  pane  or  piece  of  glass  cut 
in  a  lozenge  or  diamond  form 

Quarter,  in  heraldry:  this  word  is 
sometimes  used  for  an  escutcheon 
or  coat  of  arms :  there  are  sixteen 
quarters  required  to  prove  nobility 

Quarter  (ship's),  the  after-part  of  the 
top-side 

Quartere,  in  building,  those  slight  up- 
right pieces  of  timber  placed  be- 
tween the  puncheons  and  posts, 
used  to  lath  upon.    These  are  of 
two  sorts,  single  and  double:  the 
single    quarters    are    sawn    to   4 
inches  thick  and  4  inches  broad ; 
the  double  quarters  are  sawn  to  4 
inches  square.    It  is  a  rule  in  car- 
pentry that  no  quarters  be  placed 
at  a  greater  distance  than  1 4  inches. 

Quarter-deck,  in  ship-building,  the 
short  upper  deck  from  the  after- 
most end  of  the  main  chains  to  the 
stem 

Quarter-gallery,  the  projecting  con- 
venience and  ornament  of  the  top. 
side  which  is  connected  with  the 
stem 


QUA 


RAFTERS. 


BAF 


Quartar-pieeegy  the  carred  fignret  at 
the  aft-part  of  the  quarter-gallery 
which  joins  to  the  taffniil,  and 
forms  the  boundary  of  the  stern 

Quarterinfff  in  heraldry,  the  act  of 
dividing  a  coat  of  arms  into  four  or 
more  quarters,  by  parting,  oouping, 
•&C.,  by  perpendicular  and  hori- 
zontal Unes.  Tlie  sovereign  of  Great 
Britain  in  the  first  quarter  bears 
gules,  the  lions  passant,  or,  &c.;  in 
the  second,  formerly,  azure,  three 
fieurs-de-lis,  &c. 

Quatrefinl,  an  ornament  of  frequent 
occurrence  in  Gothic  architecture, 
formed  by  a  moulding  disposed  in 
four  segments  of  circles 

Queartf  in  mining,  crevices  in  lodes 

Queen-postf  a  vertical  timber  sup- 
porting the  rafters  of  a  trussed 
roof 

Quercitron  Lake,  or  Quercitron  Yel- 
low,  is  what  its  name  implies.  It  is 
dark  in  substance,  in  grains  of  a 
glossy  fracture,  perfectly  transpa- 
rent,  and  when  ground  is  of  a  beau- 
tiful yellow  colour,  more  durable 
than  the  common  yellow  lakes,  al« 
though  not  perfectly  permanent. 

Quick  lime,  such  lime  as  is  in  the 


RAB 

Rabbet,  that  part  of  the  keel,  stem, 
and  stem-post  of  a  ship  which  is 
cut  for  the  plank  of  the  bottom  to 
fit  into ;  the  edges  of  plank  or  deal 
for  bulk-heads  that  are  lapped  one 
over  the  other,  and  wrought  square, 
making  each  side  of  the  bulk-head 
a  smooth  surface  to  the  distance  of 
two  rooms  and  spaces 

Rack,  in  mining,  an  inclined  plane  on 
which  the  ore  and  slime  are  washed 
and  separated 

Rack,  a  fiat  bar  with  teeth  on  one 
side,  to  work  into  those  of  a  pinion 

Racking,  in  raining,  a  process  of  se- 
parating small  ores  from  the  earthy 
particles  by  means  of  an  inclined 
wooden  frame:  the  impurities  being 
washed  off,  the  ore  remaining 
near  the  head  of  the  rock  is  taken 


caustic  or  most  active  state,  and 
which  possesses  the  greatest  power 
of  operating  upon  different  sub- 
stances with  which  it  may  come  in 
contact.  It  is  quite  the  opponte 
in  its  qualities  and  properties  to 
that  which  has  fallen  down  into  a 
powdery  state,  in  conaequenoe  of 
being  saturated  with  water  and 
carbonic  add  gas  or  fixed  air,  or 
whkh  is  slaked  and  become  effete. 

Qmck-wtrk,  the  short  pieces  between 
the  ports  withinside  a  ship 

Qftmk,  in  building,  a  piece  of  ground 
taken  out  of  any  regular  ground- 
plot  or  floor:  thus,  if  the  gnmnd- 
plot  be  oblong  or  square,  a  piece 
taken  out  of  a  corner  to  midce  a 
court  or  yard,  &c.  is  called  a 
quink 

Quirk,  a  small  acute  channel  or  recess, 
much  used  between  mouldings  in 
Gothic  architecture :  in  Grecian  ar- 
chitecture ovolos  and  ogees  are 
usually  quirked  at  the  top,  and 
sometimes  in  Roman 

QuMn»  of  »tone,  the  comers  of  brick 
or  stone  walls :  when  they  stand 
out  beyond  the  brick-work,  they 
are  called  *  rustic  quoins' 


RAD 

from  thence,  and  undergoes  toss- 
ing 

Radiant  pointy  any  point  from  which 
rays  proceed 

Radhu,  in  geometry,  the  aemi-diame- 
ter  of  a  circle,  or  a  right  line  drawn 
from  the  centre  to  the  line  of  cir- 
cumference ;  in  anatomy,  a  bone  of 
the  fore-arm,  which  accompanies 
the  ulna  from  the  elbow  to  the 
wrist 

RadnU'Todt,  the  guiding  rods  in  a 
parallel  motion,  jointed  to  the  con- 
necting-links, to  counteract  the  vi- 
bratory motion  communicated  by 
the  beam,  by  guiding  the  links  so 
that  there  is  a  point 

RafterM,  in  carpentry,  the  secondary 
timbers  of  a  house;  the  timbers 
let  into  the  great  beam 


RAG 


RAILWAYS. 


RAI 


Bag-ttfmetiammmloigf.  The  Kentish 
rag-stone  is  a  kind  of  lime-stone, 
much  preferred  to  other  stones  of 
a  simihir  nature:  it  is  found  in 
beds  varying  from  6  inches  to  3  feet 
in  thickness,  and  is  compoaed  of 
the  following  substances :  carbOf 
nate  of  lime,  with  a  little  magnesia, 
92*6 ;  earthy  matter,  6  5 ;  oxide  of 
iron,  0*5;  carbonaceous  matter, 
0*4  »  100.  This  stone  is  now 
much  used. 

Rail  or  life  guardt^  in  locomotiye  en- 
gines, strong  iron  rods  reaching 
down  within  about  2  inches  of  the 
rails,  to  catch  and  throw  to  one 
side  any  obstruction  which  may  be 
on  the  rails 

Railts  the  moulding  ornaments  in  the 
top-side,  likewise  in  the  head  and 
stem  of  a  ship 

RaihoaySy  or  roads  in  which  tracks  of 
iron  or  other  smooth  material  are 
laid  for  the  easy  passage  of  wheel- 
carriages,  appear  to  have  been  in- 
troduced between  the  years  1600 
and  1650,  in  the  neighbourhood  of 
Newcastle,  to  facilitate  the  carnage 
of  the  coals  from  the  pits,  in 
'waynes'  or  waggons,  to  the 
'staythes'  or  discharging  places  on 
the  Tyne.  In  1676  they  were  de- 
scribed to  be  thus  formed :  "  The 
manner  of  the  carriage  is  by  laying 
rails  of  timber  from  the  coUiery  to 
the  river,  exactly  straight  and  pa- 
rallel; and  bulky  carts  are  made, 
with  four  rollers  fitting  those  rails, 
whereby  the  carriage  is  so  easy, 
that  one  horse  will  draw  down 
four  or  five  chaldrons  of  coals.*' 
These  *'  rails  of  timber'*  were  laid 
upon  transverse  timbers  or  sleepers, 
and  secured  with  pegs  of  wood,  the 
sleepers  being  embedded  in  the 
material  of  the  roadway. 

Before  the  year  1716,  it  became 
the  practice  to  preserve  the  edges 
of  the  rails  by  nailing  thin  plates 
of  malleable  iron  upon  their  upper 
surfaces  in  places  where  the  draught 
was  harder  than  usual.  About  the 
year  1767,  cast-iron  bars  w«re  tab- 
stitoted  for  the  wooden  rails,  and 


this  change  is  said  to  have  been 
suggested  by  the  wish  of  the  iron- 
masters to  keep  their  furnaces  at 
work  during  a  season  of  unusual 
depression  in  the  market  value  of 
their  manufactures*  These  iron 
bars  were  found  too  valuable  to 
admit  of  a  return  to  the  wooden 
rails,  and  improvements  of  various 
kinds  were  introduced.  Thus  the 
rails  were  cast  in  the  form  of  long 
narrow  plates,  vrith  a  vertical  rim 
along  one  side  (the  transverse  sec- 
tion resembhng  the  form  of  the 
letter  L),  and  thus  the  wheels  of 
the  wa^^ns  were  retained  in  their 
places  vrithout  the  projecting  rims 
or  flanges  which  were  required  for 
wheels  running  on  the  plain  rails 
or  bars.  These  rails  were  called 
'tnon'  or  'plate  rails,'  and  thus  dis- 
tinguished from  subsequent  forms 
of  iron  rails  which  were  introduced 
to  dispense  with  the  longitudinal 
timbers  heretofore  required  beneath 
them,  by  casting  the  rails  of  sufii- 
cient  depth  to  carry  their  load,  and 
of  reduced  width,  the  flanged, 
wheels  being  returned  to.  Malle- 
able-iron rails  were  introduced 
about  the  year  1815,  at  coal-works 
in  Cumberland,  with  a  view  to  re- 
medy  the  defect  of  frequent  break- 
age, to  which  those  of  cast  iron 
vrere  liable:  these  malleable-iron 
rails  were  simply  bars  of  iron  from 
2  to  3  feet  in  length,  and  1  to  2 
inehes  square ;  but  the  narrowness 
of  their  surface  was  found  to  injure 
the  wheels  so  severely,  that  the 
restoration  of  cast-iron  rails  ap- 
peared likely,  when  an  ingenious 
invention  was  made  by  Mr.  Birkin- 
shaw,  who  obtained  a  patent  in 
October,  1820,  for  his  improve- 
ments, which  consisted  in  passing 
bars  of  iron,  red-hot, between  rollers 
having  indentations  in  their  peri- 
pheries, corresponding  with  the  in- 
tended shape  of  the  rails.  By  this 
mode  malleable  •  iron  rails  were 
rolled  in  lengths  of  12  or  15  feet 
each,  and  could  be  formed  in  any 
required  shape,  the  section  varying 


RAI 


RAILWAYS. 


RAI 


throughout  the  length,  so  as  to 
give  increased  depth  and  width  at 
the  points  intermediate  between 
the  intended  bearing  pUces.  The 
rails  now  generally  used  are  pro- 
duced in  a  similar  manner,  and  the 
permanent  way  consists  of  a  levelled 
surface  of  roadway  formed  with 
metalling  or  suitable  ballasting, 
transverse  sleepers,  commonly  of 
larch,  about  9  feet  in  length,  8  to 
10  inches  in  width,  and  about  6 
inches  deep.  These  sleepers  are 
laid  from  2  feet  6  inches  to  3  feet 
apart,  and  saddles  or  chairs  of  cast 
iron  are  fastened  upon  them  with 
spikes.  Two  of  these  chain  are 
fixed  upon  each  sleeper,  at  such 
distance  apart  that  the  rails,  when 
placed  in  them,  shall  have  the  in- 
tended distance  or  guaigfi  between 
them,  commonly  4  feet  8-^  inches. 
The  rails  are  parallel  throughout, 
and  of  a  form  resembling  that  of 
the  letter  S  laid  on  one  side,  the 
depth  of  the  rail  being  about  5 
inches,  the  width  over  the  top  and 
bottom  about  2^  inches,  and  the 
thickness  of  the  middle  vertical  rib 
about  \  inch ;  all  the  angles  of  the 
section  being  carefully  retnoved  by 
rounding  the  meetings  of  the  seve- 
ral surfaces.  For  the 'broad-gauge,' 
in  which  the  rails  are  laid  7  feet 
apart,  continuous  longitudinal  tim- 
bers, about  12  inches  square,  are 
employed,  and  connected  by  cross- 
timbers  framed  to  them.  The  rails 
are  of  a  bridged  or  arched  section, 
and  rolled  with  a  projecting  plate 
along  each  side,  bolts  passing 
through  which  secure  the  rails  to 
the  longitudinal  timbers. 

The  theory  of  a  perfect  railway 
requires  that  it  should  be  level  in 
its  vertical  position  and  uniform  in 
direction.  Practically,  these  con- 
ditions are  sacrificed  within  certain 
limits ;  but  the  attainment  of  great 
speed  and  safety,  upon  the  present 
locomotiye  system,  forbids  any  very 
wide  extension  of  them.  The  con- 
sequence is,  that  great  and  expen- 
sive works  are  required  in  earth- 

368 


works,  bridges,  viaducts,  &c.,  to  | 
obtain  the  required  inclination  of  [ 
surface  and  direction.  The  cost  | 
per  mile  at  which  the  principal  . 
British  railvirays  have  been  con-  i 
structed  may  be  thus  stated  : 

Arbroath  and  Forfar  .  .  i5  9,213 
Chester  and  Birkenhead  .  34,198 
Dublin  and  Drogheda  .  .  15,652 
Dublin  and  Kingstown  .  59,122 
Dundee  and  Arbroath  .  .  8,570 
Durham  and  Sunderland  .  14,281 
Eastern  Counties  &  North-  "I    ac.%\^ 

em  and  Eastern  /  ^^"^^^ 

Edinburgh  and  Glasgow  .  35,024 
Glasgow,  Paisley,  and  Ayr  20,607 
Glasgow,  Paisley,  &  Greenock  35,015 
Grand  Junction  ....  22,293 
Great  North  of  England  .  26,855 
Great  Western  ....  56,372 
HuUandSelby  ....  22,290 
Liverpool  and  Manchester  50,923 
London  and  Birmingham  .  52,882 
London  and  Blackwall.  .288,177 
London  and  Brighton  .  .  56,981 
London  and  Croydon  .  .  80,400 
London  and  Greenwich  .  266,322 
London  and  South  Western  27,874 
Manchester  and  Birmingham  67,000 
Manchester  and  Bolton  .  61,624 
Manchester  and  Leeds .  .  47,824 
Midland  and  Bristol  and  1      oe  ^ao 

Bmnmgham  J  ' 

Newcastle  and  Carlisle  .  13,370 
Newcastle  and  Darlington  17,837 
Newcastle  and  North  Shields  44,233 
North  Union  and  Bolton  "I      ^^  a^a 

and  Preston  J      '^'»"* 

Preston  and  Wyre  .  .  .  22,261 
Sheffield  and  Manchester  .  48,543 
South  Eastern    ....     44,415 

TaffVale 19,597 

Ulster 13,946 

Yarmouth  and  Norwich  11,578 

York  and  North  Midland  .     23,066 

The  average  qwmtUie$  per  mile  I 
of  the  several  items  required  in  the  j 
formation  of  a  double  line  of  rail-  i 
way,  of  the  4-ft.  8i-in.  gauge,  up  • 
to  the  completion  of  the  permanent  I 
way,  and  exclusive  of  the  stations  ! 
and  buildings,  locomotiye  and  car-  j 
rying  stock,  may  be  computed  as  j 


RAl  RAIN- 

follows  :  The  Bverage  earth-vorks 
in  342  miles,  compriBed  in  tea 
completed  TtHvajt,  amoiint  to 
103330  cubic  yards  per  mile. 
Laod  required,  12  acres.  Ballast- 
ing. 30  feet  wide,  IB  iucbes  thick, 
8800  cubic  yarOs.  Sleepers,  8  feet 
long,  10  K  5  inchea,  placed  2  feet 
6  inches  apart,  11,733  cubic  feet, 
or  235  loads  of  timber,  or  4224 
sleepers.  Rails  in  15-feet  lengths, 
1408  lengths:  weight,  at  &6  tba. 
per  yard,  176  tons.  Chauv  for 
joints  of  rails,  140H  in  number, 
weighing,  at  20  tba.  each  1 2  tons, 
11  cwte.  1  qr.  20  Sn.:  latermediate 
chairs,  2  feet  6  inches  apart  7040 
in  number,  neighing  at  15  lbs 
each,  47  tons,  2  cwts,  3  qis  12  lbs 
Oak  trenails  and  iron  spikes  16  896 
of  each ;  with  8448  wooden  keys 
for  fixing  the  rails  in  the  chairs 
Felt,  for  chaiie,  in  pieces  10  x  5 
inchea,  2933  square  feet  Timber 
in  side  fences,  posts  B  feet  long 
6x4inche>,  9  feet  apart  4  rails 
5  x2i  inches ;  intermediate  stay 
3x2  inchea ;  total,  1 10  loads 

Of  the  quantity  of  masonry  m 
bridges,  viaducts,  culTerts  drains 
retaining-walls,  &c.,  an  average  of 
a  few  cases  gives  110  000  cubic 
feet  per  mile. 
Railway  chairt,  the  pieces  of  cast 
on   which  fix   the  rails  to  the 

Saintovt,  a  meteor  in  the  fonn  of  a 
party-coloured  arch  or  semicircle 
exhibited  in  a  rainy  sky,  opposite 
to  the  suD,  and  caused  by  the 
refraction  of  his  rays  in  the  drops 
of  falling  rain :  it  never  appears 
greater  Uian  a  semicircle,  but  often 
much  less  :  it  is  always  double, 
there  being  what  is  termed  the 
superior  and  inferior,  or  primary 
ajid  secondary  rainbow  i  they  al- 
ways exhibit  the  seven  prismatic 
colour*  ;  and  the  whole  of  this 
phenomenon  depends  upon  the 
rays  of  the  sun  tailing  on  spheri- 
cal drops  of  water,  and  being  in 
their  passage  throngh  them  re- 
fracted and  reflected 


suring  the  depth  of  rain  that 
A  very  simple  and  excellent  in. 
mcnt  for  tfais  purpose  is  show 
fig.  1.      It   consists  of  a   copper 


funnel   from  j  to  7  inches  diatne- 
ter     The  rain  being  collected  in 
glass  bottle   this  bottle  should  be 
placed  in  a  small  stand  near 
Burfece  of  the  ground   to  pn 
the  bottle  from  the  action  of  the 


Theai 


itofra 


I  fallen  1 


a  given  time  is  measured  in  a 
graduated  glass  jar  one  tenth  the 
area  of  the  funnel  similar  to  that 
shown  in  the  figure  and  so  divided 
that  every  inch  in  depth  of  the 
tube  iball  indicate  one-tenth  of  an 
inch  falling  in  the  funnel.  The 
amount  of  rtun  Ealliog  can  he  mea- 
sured by  Bucli  an  instrument  to 
jrinjth  part  of  an  inch,  or  even 

An  instrament,  flg.  2.  »  "1»" 
used  for  measuring  the  fall  of  ram. 
It  consisti  of  a  cylinder  of  copper 
ot  other  metal,  from  5  to  7  inchea 
in  diameter,  and  30  inches  long 
A  float,  just  so  much  smaller  as  t( 
allow  it  to  rise  freely  when  it 
becomes  filled  with  water,  is  placed 
ifithin  the   cyhnder,   and  t 


centre  of  the  floit  ii  attached  an 
npright  staff,  marked  in  inches  and 
ten^B  of  an  inch,  irhidi,  rising 
through  a  hole  at  the  bottom  ol 


the  funnel,  as  abonn  in  the  figure, 
indicates  the  depth  of  rain  received 
into  the  gauge. 

This  instrument  is  terj  simple, 
and  shows  the  amount  of  rain  col- 
lected upon  mere  inspection  !  it 
has,  however,  been  proved  that  in 
hillf  ^tricts  and  expoasd  situa- 
tions, when  the  staff  rises  bat  a 
small  distance  above  the  receiving 
surface  of  the  gange,  owing  to  the 
rain  being  carried  along  with  the 
wind  in  H  slanting,  and  frequently, 
on  the  tops  ot  high  bills,  slmoat  in 
a  horizontal  direction,  that  the 
staff,  though  of  small  diameter, 
arrests  a  large  arooimt  of  raio, 
which  runs  down  the  staff  and 
cantes  a  much  larger  quantity  to 
be  collected  than  is  property  due 
to  the  rain-fall.  (Some  interesting 
eiperimeutB,  showing  the  incor- 
rect recotts  ^Tcn  by  these  rain- 
gauges,  will  be  found  in  a  ■  Report 
on  the  Supply  of  Surplus  Water 
to  Uancheater,  Salhird,  and  Stock- 
port,' by  S.  C.  Homershant,  Civil 

370 


10.  RAT 

Engineer.)  'When  these  Idnd  of 
rain-gauges  are  used,  the  rod ' 
should  be  moveable,  fitting  lomely  ' 
the  socket  or  the  float,  and  only , 
placed  in  the  gauge  when  the  < 
depth  of  the  rain-faU  is  lo  bCj 
ascertuned. 

RaMine,  a  small  rope,  or  line,  some- ' 
times  nsed  to  form  the  sheer  of  a 
ship,  and  to  set  the  beams  of  thci 
deck  fair  [ 

SaJte,  in  mining,  an  obliqiie  vein         | 

Ralx,  in  ship-bnilding,  an  obtuse  | 
angle,  incb  as  the  item  and  stern- , 
posts  make  with  the  keel  ot  a  ship  i 

Rait  ^ail^,  all  that  part  of  the  I 
hull  which  btnga  over  both  ends 
of  the  keel  | 

JtoMsf  woaiidrn?,  in  joinery,  a  tnaold- 1 
ing  whose  anises  are  inclined  to '. 
the  horiion  in  any  given  angle 

AoMp,  In  hand-railing,  a  concavity 
on  the  upper  side,  formed  over ! 
risers,  or  over  half  or  quarter  span,  | 
by  a  sudden  rise  of  the  steps ' 
above,  which  frequently  occasions  i 
a  knee  shove  the  ramp  j 

Raa^aitl,  in  heraldry,  a  term  api^ied  I 
to  a  lion,  leopard,  &e.,  standing  on  : 
his  hind  legs,  in  the  escntcheon,  \ 
with  his  tore  feet  reared  np  in  the  1 
posture  of  clawing 

Rampant  Arch,  one  whose  abutments 
spring  from  an  inclined  plane 

Rangei,  pieces  fixed  to  the  inside  of ; 
a  ship  to  beUy  the  ropes ;  and 
sometimes  expressed  tor  those  be-  r 
tweentheportswheiTonthe  sbotslie  | 

Raap,  a  rough  file  i 

Ratchell,  loose  stones  \ 

Rttehet-iraet,  a  tool  for  drilHi^  a  ' 
hole  in  a  narrow  plane  vrbere  there  I 
is  not  suffleient  room  to  nse  the  ! 
common  brtce :  a  ralAet-wfaeel  is  i 
lixed  on  the  drill-sDcket,  and  tnraed  I 
by  a  handle  with  a  strong  spring  ' 
attached  to  force  roond  the  socket 
on  the  forvrard  molioii,  and  slips  [ 
over  the  teeth  on  the  backward 
motion 

SaHe  is  the  rdation  of  two  qoanti- 
tiea  of  the  same  kind  with  respect 
to  quaKty,  and  is  divided  into  I 
arithmetical  and  geometrical  | 


RAT 


REFINING. 


RBF 


Ratlin€»f  in  ship-rigging,  small  lines 
that  traverse  the  shrouds  of  a  ship 
horizontally,  at  regular  distances, 
and  form  ascending  ladders  to  the 
mast-head 

Rebate,  a  deep  groove,  or  channel, 
cut  longitudinally  in  a  piece  of 
timber  to  receive  the  edge  of  a 
plank,  or  the  ends  of  a  number  of 
planks,  which  are  to  be  securely 
fastened  in  it 

Receiver  o/  an  air-pump,  in  pneu- 
matics, a  glass  vessel  placed  on  the 
top  of  a  plate,  out  of  which  the 
air  ift  exhausted  by  the  pump 

Reeegff  a  cavity  in  a  wall,  left  either 
for  ornament  or  use  when  it  is  to 
receive  some  furniture,  as  a  side- 
board, or  to  add  to  the  quantity  of 
room ;  and  for  ornament  when 
made  in  the  form  of  a  niche,  to 
give  beauty  and  variety  to  the 
building 

Reckoning,  in  navigation,  the  compu- 
tation of  a  ship's  way  (usually  by 
the  log),  or  the  act  of  estimating 
the  distance  run  between  one  part 
and  another 

RecmcUee,  or  Top  Thnker-HoUoWf  in 
ship-building,  a  mould  sometimes 
used  to  form  the  hollow  in  the  top- 
side, which  is  called  the  reconciling 
mould 

Rectangle,  a  right  angle  made  by  the 
falling  of  one  line  perpendicularly 
upon  another 

Rectification,  in  chemistry,  is  the 
repetition  of  a  distillation  or  a 
sublimation  several  times,  in  order 
I  to  render  the  substance  purer  and 
finer,  or  freer  from  earthy  and 
aqueous  particles 

Rectification,  in  geometry,  is  the 
finding  of  a  right  Hne  equal  to  a 
proposed  curve 

Rectitineai,  or  RectiUnear,  consisting 
of  right  lines 

Rectory,  a  house  for  the  residence  of 
the  rector  of  a  parish,  usually  situ- 
ated near  the  church 

Red  is  the  second  and  intermediate 
of  the  primary  colours,  standing 
between  yellow  and  blue,  and  in 
like  intermediate  relation  aho.  to 


white  and  black,  or  hght  and 
shade.  Hence  it  is  pre-eminent 
among  colours,  as  well  as  the  most 
positive  of  all,  forming  with  yellow 
the  secondary  orange  and  its  near 
relatives,  scarlet,  &c;  and  with 
blue  the  secondary  purple  and  its 
allies,  crimson,  &c.  It  gives  some 
degree  of  warmth  to  cQl  colours, 
but  most  so  to  those  which  partake 
of  yellow. 

Red4ead,  Minium,  or  Saturnine  red, 
an  ancient  pigment,  by  some  old 
writers  confounded  with  cinnabar, 
and  caUed  Sinoper,  or  Synoper,  is 
a  deutoxide  of  lead,  prepared  by 
subjecting  massicot  to  the  heat  of 
a  furnace  with  an  expanded  sur- 
face and  f^  accession  of  air.  It 
is  of  a  scarlet  colour  and  fine  hue, 
warmer  than  common  vermillion ; 
bright,  but  not  so  vivid  as  the  bin- 
iodide  of  mercury,  though  it  has 
the  body  and  opacity  of  both  these 
ingments,  and  has  been  confounded 
even  in  name  with  vermillion,  with 
which  it  was  formerly  customary 
to  mix  it.  When  pure  and  alone, 
hght  does  not  affect  its  colour;  but 
white-lead,  or  any  oxide  or  pr^a- 
ration  of  that  metal  mixed  with 
it^  soon  deprives  it  of  colour,  as 
acids  do  also ;  and  impure  air  will 
blacken  and  ultimately  metaUize 
it. 

Red  Oehre  is  a  name  proper  rathw  to 
a  class  than  to  an  indiridoal  pig- 
ment, and  comprehends  Indian  red, 
light  red,  Venetian  red,  scarlet 
odire,  Indian  ochre,  redding,  rud- 
dle, bole,  as  well  as  other  absurd 
appellations,  such  as  English  ver- 
million, and  Spanish  brown,  or 
majoHca 

Reef,  in  navigation,  to  contract  a 
sail  by  tying  up  a  portion  of  it  to 
the  yard 

Refectory,  a  refreshment-room;  the 
hall  or  apartment  in  a  monastery 

Refining  and  Puddling  of  Iro9i.  The 
chemical  difference  between  cast 
iron  and  wrought  iron  consists 
principally  in  the  difference  of  de- 
gree in  which  foreign  matters  are 


371 


RGF 


REFRACTION. 


REF 


present  in  each,  which  is  in  hirger 
amount  in  the  former  than  in  the 
latter.  There  are  many  cases  in 
ivhich  wrought  iron  contains  a 
larger  amount  of  impurities  than 
cast  iron,  and  is  yet  malleahle; 
while  cast  iron  of  the  same  com- 
position may  he  very  hard  and 
brittle.  Berzelius  detected  in  a 
certain  kind  of  bar  iron,  18  per 
cent,  of  silex ;  and  yet  this  iron 
was  still  malleable  and  useful. 
One-tenth  of  that  amount  of  silex 
will  make  cast  iron  brittle.  The 
foreign  matters  generally  combined 
with  pig  iron  are  carbon,  silicon, 
silex,  sidphur,  phosphorus,  arsenic, 
zinc,  manganese,  titanium,  chrome, 
aluminum,  magnesium,  and  cal- 
cium. Each  of  these  tends  to 
make  iron  brittle;  therefore,  in 
converting  cast  into  wrought  iron, 
it  is  necessary,  as  far  as  possible, 
to  remove  them .  Carbon  and  other 
foreign  matters  divide  the  crude 
iron  into  two  very  distinct  classes. 
In  the  one,  carbon  is  only  an  acci- 
dental  mechanical  admixture;  in 
the  other,  it  is  in  definite  chemical 
combination.  To  the  first  belong 
the  white  iron  of  heavy  burden, 
and  gray  iron ;  to  the  latter,  the 
white  iron  of  small  burden,  or  very 
fusible  ores.  From  the  behaviour 
of  the  different  metals  in  the  refin- 
ing and  puddling  process,  the  pre- 
sence of  silicon  and  silex  appears 
to  exert  a  similar  influence:  it  is 
not  possible  to  remove  silex  from 
white  metal  with  which  carbon  is 
chemically  combined.  The  silex  is 
present  in  the  form  of  silicon. 
White  metal  of  small  burden  may 
contain  from  5  to  nearly  6  per 
cent,  of  carbon;  and,  if  smelted 
from  pure  ore,  almost  an  equal 
amount  of  other  foreign  matter, 
such  as  silicon.  Upon  the  pre- 
sence and  form  of  these  its  white 
colour  and  crystallization  in  a  de- 
gree depend.  Gray  pig  iron  seldom 
contains  more  than  4*75  per  cent, 
of  carbon,  and  generally  only  from 
3*50  to  4  per  cent.    When  carbon 

172~ 


is  present  to  the  amount  of  but  2 
to  3  per  cent.,  it  becomes  white. 
The  more  this  iron  is  stretched, 
the  more  it  forms  fibres.  Fibrous 
bar  iron  resembles  hickory  wood, 
in  the  fact  that  it  is  a  combination 
of  fibres  and  spaces.  In  bar  iron 
these  spaces  are  filled  with  cinders, 
and  that  portion  of  the  iron  is 
proportional  to  the  fineness  of  the 
fibres.  That  portion  of  the  iron 
which  is  not  melted,  which  crys- 
taUizes  too  fast,  or  whose  prema- 
ture crystalUzation  the  wrorkman 
cannot  prevent,  is  in  the  condition 
of  cast  metal,  and  cannot  be  con- 
verted into  fibrous  wrought  iron. 
In  the  puddling  furnace  it  is  ne- 
cessary to  prevent  crystaUization 
by  manual  labour.  This  result, 
whether  in  the  Catalan  forge,  the 
Woolf  s  oven,  or  the  German  forge, 
is  partly  accomplished  by  the 
blast. 

Re/lection  is  the  return  or  regressive 
motion  of  a  moveable  body,  arising 
from  the  reaction  of  some  other 
body  on  which  it  impinges 

Re/lex,  in  painting,  denotes  those 
parts  of  a  picture  that  are  supposed 
to  be  illuminated  by  a  light  re- 
flected from  some  other  body  re- 
presented in  the  piece 

RefluuPf  in  hydrography,  the  ebb,  back- 
ward course  of  water,flux,  orflowing 
of  the  sea 

Refraction^  in  mechanics,  the  incur- 
vation or  change  of  determination 
in  the  body  moved.  In  dioptrics, 
it  is  the  variation  of  a  ray  of 
light  from  that  right  line  in  which 
it  would  have  passed  on,  had  not 
the  density  of  the  medium  turned 
it  aside.  It  is  the  bending  of  a  ray 
of  light  towards  the  perpendicular 
when  it  passesinto  a  denser  medium, 
and  from  the  perpendicular  when 
it  passes  into  a  rarer  medium. 

The  law  of  refraction  was  first 
completely  established  by  Snell  and 
Descartes  at  the  commencement  of 
the  seventeenth  century.  The  first 
part  of  this  law  is  similar  to  that 
qf  reflection,  viz.  that  the  angles  of 


inddence  and  refraction  (t. «.  the 
aaglM  vhich  the  incident  and  re- 
feaiieA  ray  each  make  with  the  per- 
pendicular or  norm&I  of  the  lurface, 
or  in  this  case  the  aiigleB  p  c  d  and 
r'  c  d")  are  both  in  the  same  plane. 
Any  ray  meeting  the  imface  of  a 
nev  medium  ii  iplit  into  two  rays, 
one  reflected  and  the  other  re- 
dacted ;  >a,  far  initance,  the  ray 
B  c  into  the  reflected  ray  c  b",  and 
the  refracted  ray 


the  t 


also  a  ray  h"c  will  be  partly  re- 
flected in  the  direction  c  £',  and 
partly  refracted  into  c  b  ;  or  d"  c 
^rill  be  reflected  into  c  ^,  and  re- 
fracted into  c  D.  Now  in  all  these 
cases  the  three  rays,  incident,  re- 
flected, and  refracted,  will  be  all 
in  one  plane,  and  tl^at  plane  per. 
pendlcular  to  the  acting  gnrface 

The  angles  of  incidence  and  re- 
flexion (Bucb  as  F  c  D  and  f  c  d') 
are,  aa  already  explained,  invuiably 
equal ;  hut  that  of  refraction  (in 
ttiia  caae  f*  c  n")  is  different  from 
both,  but  connected  witb  them  by 
this  law,  that  (at  the  lame  gnrface) 
the  ainea  of  incidence  and  refraction 
to  the  same  radiue  bear  a  constant 
ratio  to  each  other,  which  i»  always 
the  same  in  the  rame  two  media. 

\B r._  .„. 


1  ■'■' 

\ 

■  i     -J^ 

i: 

-^ 

^^ 

V 

i'/ 

Pot  instance,  in  pasair^  through 
thesurfacexA,  at  whatever  degree 
of  ohliqnity,  and  whether  upwards 
from  the  water  into  the  air,  or  down 


HON.  RE 

is  inTariably  bo  bent  that  the  ang 
it  makes  with  tbc  perpendicuh 
Fp'  in  the  air  may  be  greater  tha 
that  in  the  water;  and  that  th 
sine  of  the  angle  in  air  may  he  t 
that  in  water  (to  the  Bsme  radiut 
as  4  to  3,  which  is  the  laUo  tht 
hai  been  determined  by  expei 
meat.  At  the  surface  separatii 
any  other  two  media,  a  differs 
ratio  would  be  observed  with  equ 
constancy. 

To  find  the  new  direction  inb 
which  any  ray,  such  as  n  c,  will  hi 
bent  by  this  surface,  draw  a  circli 
round  the  point  c  with  any  radius, 
such  as  c  B,  and  the  sine  of  the  ray 
in  air  (to  tbii  radius)  will  be  found 
to  be  a  B.  Therefore  the  sine  in 
water  will  be}  of  8  a.  Draw  a  line 
parallel  with  c  p  at  a  distance  theie- 
Irom  equal  to  }  of  s  a,  viz.  at  the 
distance  s's",  andai  this  intersects 
the  circle  at  b",  the  refracted  ray 
must  pass  through  a"  to  make  its 
Bin.  i.  w.«,  (/.")  totil.  .in. 
in  air  (s  s),  both  to  the  same  radius 
(cB.or  cs")-  If  any  other  radius 
be  chosen,  as  c  «,  it  is  plain  that 
the  eame  result  will  he  obtained; 
for,  by  the  property  of  similar  tri- 
angles, if  a'  s"  be  J  of  a  s,  then 
iV' is  also  \  ottt. 

In  tracing  the  course  of  a  ray 
upwards  from  the  water,  as  o"  c, 
then,  having  found  its  sine  in  water 
to  any  fiied  radius,  make  its  sine  in 
air  1  greater,  because  the  sine  in 
air  ia  always  greater  than  that  in 
water,  as  4  : 3 ;  and  thus  the  new 
direction  ol  Itie  isy  will  be  founa 
to  be  c  !>■  ,      ^ 

In  this  case  a  very  singuUi  effee 
takes  place  if  the  ray  be  ver 
oblique  to  the  surface,  as  r  c. 
should  be  remarked  Jbf.  "°  " 
passing  froB.  the  wr  into  th^  wM< 
however  obUquely.  «>''^'^„"" 
refracted  into  the  direction  «  f 
this  reason,  the  sine  of  ^°^ 
can  be  greater  than  the  r^"' 
Which  it  is  .drawn,  tberef«|.^° 
can  ba'e  ita  ame  'o  ■  . 
greater  thanes.     Putjtsj^ 


REF 


REFRACTION. 


REF 


water  is  only  f  of  that  in  air,  and 
consequently  cannot  exceed  f  of 
the  radius.  Now  the  sine  of  the 
ray  c  f,  viz.  v  ;,  is  more  than  f  of 
the  radius  c  s,  therefore  no  degree 
of  obliquity  of  the  ray  in  air  will 
enable  it  to  become  so  oblique  in 
the  water  as  c  f.  But  a  ray  may 
ascend  in  the  direction  f  c  as  well 
as  in  any  other.  Now  its  sine  in 
air  must  become  ^  greater  than  f  z; 
but  this  is  impossible,  for  a  line  i 
longer  than  fz  would  be  longer 
than  the  radius  c  s,  and  therefore 
too  long  to  be  the  sine  of  any  angle 
to  that  ra£u8.  As  this  ray,  then, ' 
cannot  be  refracted  according  to 
the  law,  it  is  not  refracted  at  all, 
but  totally  reflected  in  the  direction 
c/,  the  only  known  instance  of 
total  reflection,  for  none  of  the  light 
can  penetrate  the  surface  a  a,  which 
is,  in  fact,  absolutely  opaque  to  this 
light.  This  phenomenon  of  total 
reflection  may  be  seen  by  looking 
through  the  side  of  a  tumbler  con- 
taining water  up  to  its  surface,  in 
some  such  direction  as  /c,  when 
the  surface  willbe  seen  to  be  opaque, 
and  more  reflective  than  any  mirror, 
inasmuch  as  the  images  in  it  are 
perfectly  equal  in  brightness  to  the 
objects  themselves. 

Now  at  the  surface  between  any 
other  two  media,  the  ratio  of  the 
sines  would  be  different ;  for  though 
all  surfaces  reflect  alike  (as  re- 
gards the  direction  of  the  ray), 
all  do  not  refract  alike.  Suppose 
the  ray  passed  from  vacuum  into 
water,  the  ratio  would  be  rather 
greater  than  3 : 4,  namely  1 :  1*335. 
In  passing  from  vacuum  into  air  of 
the  common  density,  the  refraction 
would  be  much  less,  and  conse- 
quently the  sines  much  more  nearly 
equal,  viz.  as  1:1-000294.  Now 
if  the  sine  in  any  medium  be  called 
1 ,  the  corresponding  sine  in  vacuo 
is  called  the  index  of  refraction  of 
that  medium;  and  is  specific  for 
each  substance,  or  as  constant  as 
its  density,  expansibility,  specific 
heat,  or  any  other  measurable  qua- 

374 


lity.  Thus  the  refractive  index  of 
air  of  the  common  density  is 
1000294,  that  of  water  1-335,  of 
crown  glass  1*52,  of  flint  glass  1*55. 

In  the  case  above  considered, 
of  refraction  frx>m  air  into  water, 
and  vice  verad,  the  sines  in  air  and 
in  water  are,  strictly  speaking,  as 
1-335  : 1-000294 ;  and  generally  the 
sines  on  each  side  of  any  surface 
are  inversely  as  the  refractive  in- 
dices of  the  two  media. 

The  refractive  indices  of  a  great 
many  media  have  been  measured 
and  arranged  in  tables.  When  the 
density  of  any  substance  is  increased 
or  diminished,  its  refractive  power 
is  increased  or  diminished  in  the 
same  ratio. 

The  application  of  the  laws  of 
refraction  accounts  for  numerous 
deceptive  effects  seen  in  the  atmo- 
sphere,   and  included  under  the 
general  term  mirage;  the  most  fa- 
miliar of  which  is  the  distortion  of 
objects  seen  through  a  rising  cur- 
rent of  hot  air,  which,  from  its 
smaller  density,  has  a  lower  re- 
fractive power  than  the  surrounding 
cold  air,  and  therefore  bends  the 
rays  in  various  directions.     It  is 
also  plain  that  the  rays    of  the 
heavenly  bodies  coming  from  space 
into  our  atmosphere  must  be  re- 
fracted, and  thus  cause  the  objects 
whence  they  come  to  appear  rather 
above  their  true  place,  as  the  eye 
at  d  in  the  figure  sees  d  in  the 
direction  d  c  rather  above  its  true 
place.     This   forms    one    of    the 
sources  of  error  to  be  allowed  for 
in  all  astronomical  observations, 
and  tables  are  calculated  for  finding 
its  amount,  depending  on  the  ob- 
ject's apparent  altitude,  and  the 
state  of  the  barometer  and  ther- 
mometer.   Owing  to  the  very  small 
refractive  power  of  air,  however, 
this  error  is  hardly  sensible  when 
the  object  is  high,  but  increases 
rapidly  towards  the  horizon,  where 
it  becomes  33',  or  rather  more  than 
the.  sun's  or  moon's  diameter,  so 
that  these  bodies  may  appear  just 


HEG 


REGULATOR, 


REP 


clear  of  the  horizon  when  they  are 
reaUy  completely  below  it.  As  the 
density  of  the  air  diminishes  gra- 
dually upwards,  atmospheric  re- 
fraction is  not,  like  that  which  has 
been  just  considered,  a  sudden 
change  of  direction,  but  the  ray 
actually  describes  a  curve,  being 
refracted  more  and  more  at  every 
step;  and  this  applies  equally  to 
the  light  from  a  distant  terrestrial 
object  which  is  either  lower  or 
higher  than  the  eye,  because  it  must 
pass  through  air  of  constantly  in- 
creasing or  diminishing  density. 
This  r^raction  has  therefore  to  be 
allowed  for  in  levelling,  which  is 
done  by  assuming  that  the  light 
from  a  distant  object  comes  to  us 
in  a  line  arched  or  curved  upwards, 
the  radius  of  which  is  about  seven 
times  that  of  the  earth. 

The  application  of  these  laws  of 
Dioptrics  has  also  led  to  the  under- 
standing  of  the  mechanism  of  the 
eye,  and  hence  to  the  imitation 
thereof  by  lenses,  affording  the  re- 
medies for  its  infirmities  of  long 
and  short  sight,  and  disclosing  the 
wonders  of  the  telescope  and  the 
microscope. 
jRepra/ta,  in  heraldry,  ensigns  of  royalty; 
the  apparatus  used  at  a  coronation 
Regardant,  in  heraldry,  signifies  look- 
ing behind,  as  appUed  to  a  lion  or 
any  other  beast 
Regatta^  the  name  of  an  aquatic  spec- 
tacle consisting  of  gondola  races, 
&c.,  exhibited  at  Venice 
RegMf  a  fiat  narrow  moulding,  em- 
ployed to  separate  panels  or  other 
members ;  or  to  form  knots,  frets, 
and  similar  ornaments 
RegtUa,  a  band  below  the  ttenia  of 
the  Doric  epistylium,  extending  the 
width  of  the  triglyph,  and  having 
six  gnttse  depending  from  it.     It 
also  signifies  the  space  between  two 
adjoining  canals  of  the  triglyphs. 
Regular,  In  geometry,  a  regular  body 
is  solid  whose  surface  is  composed 
of  regular  and  equal  figures,  and 
whose  solid  angles  are  all  equal. 
There  are  five;sort8  :  1.  A  pyramid, 

375 


comprehended  under  four  equal  and 
equilateral  triangles:  2.  A  cube, 
whose  sur&ce  is  composed  of  six 
equal  squares:  3.  That  which  is 
bounded  by  eight  equal  and  equi- 
lateral triangles :  4.  That  which  is 
contained  under  twelve  equal  and 
equilateral  pentagons:  5.  A  body 
consisting  of  twenty  equal  and  equi- 
lateral triangles. 

Regulator,  In  mechanics,  that  part  of 
a  machine  which  makes  the  motion 
equable 

Regulator-cock,  in  locomotive  en- 
gines, a  cock  placed  to  admit  oil 
or  tallow  to  lubricate  the  faces  of 
the  regulator 

Regulator-cover,  in  locomotive  en- 
gines, the  outside  cover,  remove- 
able  when  required  to  examine  the 
regulator 

Regulatorsh(fi  and  levers,  in  loco- 
motive engines,  the  shaft  and  levers 
placed  in  front  of  the  smoke-box 
when  each  cylinder  has  a  separate 
regulator.  A  rod  connected  with 
the  shaft  leads  to  the  foot-plate, 
where  a  handle  is  placed  conve- 
niently for  use. 

Regulator-vahe,  the  valve  in  a  steam- 
pipe  of  a  locomotive  engine,  for 
regulating  the  supply  of  steam  to 
the  cylinders 

Regulator-vab>e  epmHe,  the  spindle 
for  moving  the  regulator-valve; 
being  fixed  to  it  at  one  end,  the 
other  end  of  the  spindle  passes 
through  a  stuffing-box  joint  over 
the  fire-box,  and  has  a  handle  fixed 
on  the  end  to  turn  it 

Relief-valve,  a  valve  belonging  to  the 
feeding  apparatus  of  a  marine  en- 
gine, through  which  the  water 
escapes  into  the  hot  well  when  it 
is  shut  oflf  from  the  boiler 

Relieving  tackle,  in  mechanics,  the 
two  strong  tackles  used  to  prevent 
a  ship's  overturning  on  the  careen, 
and  afterwards  to  assist  in  upright- 
ing  her 

Repercuaeion,  in  mechanics,  the  act 
of  drawing  back ;  rebound 

Rephtm,  the  panel  of  the  impagis,  or 
horizontal  rails  of  a  framed  door 


RET 


RHOMB. 


RHO 


RepoiBf  in  painting,  denotes  certain 
parts  in  the  composition  of  a  pic- 
ture which  seem  to  tranquillize  its 
aspect 

Reredost  behind  the  back ;  the  back 
of  a  fire-place ;  also  an  altar-piece, 
a  screen,  or  partition  wall 

Respond,  in  Gothic  architectore,  a 
half-pillar  or  piece  attached  to  a 
wall  to  support  an  arch,  &c. 

Reatf  in  a  lathe,  a  piece  of  iron  to 
hold  the  tuming-tool  upon,  fixed 
at  the  end  of  a  slide  by  a  set- 
screw  :  the  slide  can  be  moved  at 
right  angles  to  the  bar  of  the  lathe, 
and  the  whole  can  be  fixed  at  any 
part  of  the  bed,  between  the 
centres 

Reticulated  work,  a  species  of  ma- 
sonry or  break-work,  formed  exter- 
nally by  small  square  stones  or 
bricks,  placed  lozenge-wise,  and 
presenting  the  appearance  of  net- 
work 

Reticulation  is  the  method  of  copy- 
ing a  painting  or  drawing  by  the 
help  of  square  threads.  An  open 
frame  is  made  similar  to  a  strain- 
ing frame,  and  the  painting  en- 
closed within  it :  a  number  of 
threads  are  then  strained  over  at 
equal  distances,  like  net-work, 
which  are  fastened  to  the  firame  by 
nails.  The  canvas,  or  paper,  is 
likewise  divided  into  an  equal 
number  of  proportional  squares, 
and  whatever  appears  within  the 
square  threads  in  the  painting  is 
copied  into  the  corresponding 
squares  on  the  canvas  or  paper. 
The  squares  of  the  copy  may  bear 
any  proportion  to  those  of  the  ori- 
ginal. Painters  often  adopt  this 
method  when  they  first  execute  a 
small  design,  from  which  their 
large  and  more  finished  work  is 
copied. 

Revels,  or  Reveals,  the  vertical  re- 
treating surface  of  an  aperture,  or 
the  two  vertical  sides  of  the  aper- 
ture, between  the  front  of  the  wall 
and  the  vnndows  or  door  frames, 
most  commonly  posited  at  right 
angles  to  the  upright  surfiace 

376 


Reversing  gear,  the  apparatua  for 
reversing  the  motion  of  a  marine 
or  locomotive  engine,  by  changing 
the  time  of  action  of  the  sUde- 
valve :  the  eccentric  being  in  ad- 
vance of  the  crank  for  the  forward 
motion  will,  if  turned  to  an  equal 
distance  behind  the  crank,  produce 
a  backward  motion 

Reversing  handle  and  guide,  the  han- 
dle placed  beside  the  foot-plate 
conTcniently  for  use  when  re- 
quired. The  guide  is  a  quadrant 
fixed  to  the  foot-plate,  notched  for 
the  end  of  the  reversing  handle  for 
each  variation  of  the  expansion 
gear.  To  reverse  the  engine,  the 
handle  is  removed  to  any  notch 
past  the  centre  of  the  guide  on  the 
opposite  side  in  which  it  was  be- 
fore. Expansion  is  varied  by  mov- 
ing the  handle  from  one  notch  to 
another  notch  on  the  same  side  of 
the  centre  of  the  guide  firom  which 
the  engine  is  working.  When  the 
handle  is  on  the  centre  notch,  the 
engine  is  said  to  be  out  of  gear. 

Reversing  lever,  the  lever  connecsted 
to  a  crank  on  the  reversing  shaft 
by  a  rod,  and  placed  at  the  side  oi 
the  fire-box,  between  guide-plates 
with  notches  to  keep  it  vertical, 
or  in  the  forward  or  backward 
position 

Reversing  shaft,  the  shaft,  with  levers 
on  it,  connected  with  the  eccsentric- 
rods  in  the  rocking-shaft  class,  but 
vrith  the  slide-valve  rod  in  the 
expansion-gear  class  of  engines. 
Both  arrangements  effect  the  ob- 
ject of  moving  the  slide-valve  so 
as  to  admit  steam  to  the  contrary 
side  of  the  piston  to  which  it  had 
previously  been  admitted,  and  thus 
reverse  its  motion,  and  with  it  the 
motion  of  the  engine  also. 

Reversing  valve,    (See  Air-vahe). 

Rhomb,  an  oblique  angled  parallelo- 
gram; in  geometry,  a  parallelogram 
or  quadrangular  figure  having  its 
four  sides  equal,  and  consisting  of 
parallel  lines,  with  two  opposite 
angles  acute  and  two  obtuse 

Rhomboidal,  approaching  the  shape 


RHU 


ROADS. 


ROA 


of  a  rhomb :  in  geometry,  used  to 
signify  an  oblique-angled  paral- 
lelogram 

Rhumb f  in  navigation,  a  yertical  cir- 
cle of  any  given  place,  or  the 
intersection  of  a  part  of  such  circle 
with  the  horizon.  Rhumbs  coin- 
cide with  the  points  of  the  world 
or  horizon,  and  are  distinguished 
like  those  of  the  compass.  A 
rhumb-line  cuts  all  the  meridians 
under  the  same  angle. 

Ribf  in  constructive  architecture,  a 
moulding  on  the  interior  of  a 
vaulted  roof 

Ribf  an  arch  formed  of  a  piece  of 
timber 

Rib^  a  pillar  of  coal  left  as  a  support 
for  the  roof  of  a  mine 

RibSy  arch-formed  timbers,  for  sus- 
taining the  plaster-work  of  a  vault, 
or  wood  ceiling 

Ribbandf  pieces  of  fir  nailed  to  the 
timbers  of  a  square  body  under 
which  shores  are  fixed 

Ribbingy  the  whole  of  the  timber- 
work  for  sustaining  a  vaulted  or 
coved  ceiling 

Riders,  in  ship-building,  interior  ribs, 
to  strengthen  and  bind  the  parts  of 
a  ship  together,  being  fayed  upon 
the  inside  stuff,  and  bolted  through 
aU 

Ridge,  the  upper  angle  of  a  roof :  tiles 
called  ridge -tiles  are  sometimes 
made  very  ornamental. 

Rigger,  a  wheel  with  a  flat  or  slightly 
curved  rim,  moved  by  a  leather 
band 

Right  angle,  in  geometry,  is  that 
formed  by  a  Une  fallhig  perpen- 
dicularly on  another,  or  that  which 
subtends  an  arc  of  ninety  degrees 

Right  line,  in  geometry,  signifies  the 
same  as  a  straight  line,  opposed  to 
curved  or  crooked 

Ring,  in  geometry,  an  annulus 

Rtng-tail,  in  navigation,  a  quadrilate- 
ral sail,  occasionally  hoisted  abaft 
the  after-leech  of  the  boom  main- 
sails, to  which  the  fore-leech  is 
made  to  correspond 

Rising-rod,  a  rod  in  a  Cornish  engine 
which  rises  by  means  of  levers  as 

377 


the  cataract  piston  descends,  and 
lifts  catches  which  release  sectors, 
and  allow  "v^lghts  to  shut  or  open 
the  steam,  equilibrium,  or  exhaust 
valve 
Rivets,  short  bolts  of  metal  inserted 
in  a  hole  at  the  juncture  of  two 
plates,  and,  after  insertion,  ham- 
mered broad  at  the  ends,  so  as  to 
keep  the  plates  together.  Mr.  Wm. 
Fairbaim  invented  a  riveting  ma- 
chine, which  by  the  aid  of  steam 
performs   the    work  rapidly  and 
without  noise. 
Riveting  Machine.    The  principle  of 
action  of  the  riveting  machine  is 
very  similar  to  that  of  an  ordinary 
punching  machine.  The  work  per- 
formed by  it  is  usually  done  by 
manual  labour,  which  occupies  a 
much  longer  time,    causes  great 
noise,  and  is  much  more  expensive 
and  less  efildent.     The  machine 
consists  of  two  strong  side-frames 
forming  bearings  for  the  fulcrum 
for  a  powerful  lever  which  works 
between  them,  and  is  raised  or 
lowered  by  a  cam  acting  at  the  ex- 
tremity.   On  one  end  of  the  cam- 
shaft is  a  large  spur-wheel  moved 
by  a  pinion  on  the  driving-shaft, 
which  has  a  very  heavy  fly-wheel 
fixed  on  it,  to  accumulate  power 
and  expend  it  during  the  action  of 
the  lever.     The  riveting  tool  is 
placed  in  a  guide  near  the  short 
end  of  the  lever,  and  directly  op- 
posite the  end  of  the  tool  is  ano- 
ther, to  form  the  heads  fixed  on  a 
pillar  called  the  riveting-block.  The 
rivet  being  made  to  enter  the  holes, 
and  placed  between  the  riveting 
tool  and  the  block,  the  machine 
is   set  in  motion,  and  the  cam 
raises    the    lever,  which   presses 
against  the  tool  and  instantly  forms 
the  rivet. 
Roads  are   artificially -formed   ways 
between  distant  places,  and  being 
among  the  first  means  of  personsd 
communication,    their    formation 
and  treatment,  as    duties  of  the 
engineer*,  are  of  the  highest  im- 
portance.   The  eflJciency  of  road- 


ROA 


ROAD-MAKING. 


ROA 


maldng  requires  that  the  Burface  of 
the  road  shall  be  preserved  in  a 
durable  condition,  and  adapted  for 
the  kind  of  traffic  to  be  conducted 
upon  it ;  and,  therefore,  the  con- 
struction of  the  roadi  both  as  re- 
gards its  superstratum  or  surface, 
and  substructure,  its  dimensions 
and  inclination,  or  declivity-,  are 
equally  to  be  determined  with  re- 
ference to  the  particular  kind  of 
wear  to  which  it  will  be  subjected. 
Thus  the  weights  that  will  pass 
over  the  road  will  make  it  neces- 
sary that  it  possess  greater  or  less 
firmness  and  solidity,  while  the 
rigidity  or  hardness  of  its  surface 
affects  the  power  required  for  mov- 
ing bodies,  or  the  draught.  The 
vertical  inclination  of  the  road  has 
an  influence  upon  the  draught,  and 
is  also  limited  by  the  class  of  traffic. 
The  old  Roman  roads,  for  instance, 
designed  for  the  passage  of  animals 
only,  were  laid  with  inclinations  of 
great  steepness,  and  with  r^erence 
only  to  the  directness  of  their 
course.  The  use  of  wheel  carriages 
imposes  limits  to  the  steepness 
which  cannot  be  exceeded  either 
with  safety  or  with  economy  of 
power.  The  most  improved  form 
of  road — ^the  railway — restricts  the 
steepness  or  inclination  still  further, 
the  propelling  power  employed 
being  found  to  become  expensive 
in  a  rapid  ratio  in  proportion  to  the 
departure  of  the  surface  on  which 
it  is  exerted  from  a  horizontal 
plane.  The  qualities  of  a  good 
road  are,  solidity  of  structure, — 
hardness  of  surface, — ^levelness  of 
inclination,  and  sufficiency  of  width 
for  all  its  purposes.  To  insure  the 
permanence  of  these  qualities,  the 
formation  and  the  drainage  of  the 
road  are  required  to  be  complete, 
while  the  several  means  to  be 
adopted  will  be  partly  determined 
by  the  kind  of  materials  at  com- 
mand. Experiments  made  to  as- 
certjun  the  force  of  traction  on  dif- 
ferent kinds  of  roads,  have  shown 
that  this  force  is  nearly  in  exact 

378 


proportion   to    the  strength   and 
hardness  of  the  road.     Thus   the 
draught  on  a  well-made  pavement 
is  hsJf  that  upon  a  broken  stone 
surface,  or  old  ffint  road,  and  less 
than  a  quarter  of  the  draught  npon 
a  gravel  road.    If  the  strength  or 
solidity  of  the  foundation  be  in- 
creased, the  draught   is  reduced. 
Thus,  if  the  broken  stone  road  be 
laid  upon  a  rough  pavement  foun- 
dation, the  draught  is  reduced  one- 
third,  and  a  similar  reduction  is 
effected  by  laying  a  bottoming  of 
concrete  formed   of  cement   and 
gravel.      The  external  forces  by 
which  the  motion  of  bodies  upon 
roads  is  retarded,  and  the  draught 
or    power   required  consequently 
augmented,  are  collision,  friction, 
gravity,  and  the  atmosphere.     Col- 
lision is  occasioned  by  the  hard 
protuberances  and  irreg^arities  of 
surface  of  the  road  meeting  the 
wheels,  and  thus  diminishing  the 
momentum  of  carriages.     The  re- 
sistance arising  from  collision  is 
proportional  directly  to  the  load 
and  the  height  of  the  obstacle  to 
be  surmounted,  and  inversely  to 
the  diameter  of  the  wheels  oi  the 
carriage  in  which  the  load  is  borne. 
Professor  Leslie  has  defined   the 
resistance  which  friction  causes  to 
consist  ^*  of  the  consumption  of  the 
moving  force,  or  of  the   horse's 
labour,  occasioned  by  the  soft  sur- 
face of  the  road,  and  the  continu- 
ally depressing  of  the  spongy  and 
elastic  substrata  of  the  road.'*  From 
the  formulie  which  have  been  de- 
duced upon  the  extent  of  this  re- 
sistance, it  is  evident  that  it  is 
caused  by  the  wheels  sinking  into 
the  ground,  and  is  proportional  di- 
rectly to  the  load,  and  inversely  to 
the  width  of  the  wheels.    The  re- 
sistance   produced  by  gravity  is 
evidently    in    proportion    to    the 
steepness  of  the  road,  being  nothing 
on  a  perfectly  horizontal  plane,  and 
augmenting  as  the  inclination  ap- 
proaches the  perpendicular.     The 
force  of  the  air  in  resisting  the 


f 


ROA 


ROCKING-SHAFT. 


ROC 


motion  of  loads  upon  roads  may  be 
understood  from  the  experiments 
which  are  given  in  Smeaton's  Re- 
ports, and  from  which  it  appears, 
that  upon  a  surface  of  one  square 
foot  this  force  equals  1  tb.  when 
the  velocity  of  the  wind  is  at  the 
rate  of  15  miles  per  hour ;  and  that 
this  force  becomes  equal  to  1 2  lbs. 
when  the  air  moves  at  the  rate  of 
50  miles  an  hour,  constituting  a 
storm. 

In  designing  a  road,  a  correct 
survey  of  the  proposed  line,  with 
the  exact  relative  levels  of  all  parts 
of  its  present  surface,  is  the  first 
requisite,  and  upon  this  the  engi- 
neer proceeds  to  consider  the  pro- 
priety of  deviating  in  one  direction 
or  another,  in  order  to  attain  better 
levels,  or  to  equalize  the  earth- 
works, so  that  the  quantity  exca- 
vated in  one  part  may  siiffice  to 
embank  an  adjacent  portion,  and 
thus  reduce  the  distances  to  which 
the  soil  must  be  removed.  In  de- 
termining the  inclinations  of  the 
surface,  facts  proved  by  experience 
should  be  consulted,  from  which 
the  rule  may  be  inferred  that  an 
inclination  of  1  in  35  is  that  which 
admits  of  horses  moving  with  per- 
feet  safety  in  a  fast  trot.  Valleys 
are  required  to  be  crossed  by 
bridges  and  viaducts,  or  solid  em- 
bankments and  hills  are  excavated 
with  cuttings  or  with  tunnels  to 
reduce  the  elevation  to  which  it 
would  otherwise  be  necessary  to 
carry  the  road.  Streams  and  rivers 
are  also  occasionally  to  be  passed 
over,  and  thus  the  design  and  exe- 
cution of  an  extended  length  of 
road  frequently  involves  some  of 
the  grandest  works  of  engineering 
art. 

Road-making  was  a  principle  of 
employment  ingeniously  carried  out 
by  Napoleon  in  those  countries 
mastered  by  his  arms;  he  disco- 
vered one  element  of  the  mixing  of 
the  poorer  population  by  the  mono- 
polies and  greediness  of  the  rich ; 
his  master  mind  saw  clearly  that  he 

379  " 


could  not  better  secure  his  power 
than  by  employing  the  unfortunate 
and  labouring  poor.  Road-making 
zealously  occupied  his  mind:  his 
name  to  this  day,  for  this  simple 
and  important  fact,  is  revered.  In 
those  towns  on  the  Continent  where 
a  r^sum^  existed  of  the  antagonistic 
principle,  it  is  obvious  that  pau- 
perism may  be  staved  oflf  by  the 
more  wealthy  lords  of  the  soil,  if 
they  give  employment  to  the  poor ; 
and  such  conduct  on  the  part  of 
Napoleon  naturally  produced  a  ve- 
neration for  his  name.  These  poor 
people  desired  no  cold  charity ;  they 
sought  for  sustenance  by  the  means 
of  useful  labour ;  and  one  of  these 
was  road-making.  Many  of  them 
cheerfully  shouldered  the  musket 
for  the  man  who  had  so  cherished 
them.  Among  the  great  projects 
carried  out  may  be  mentioned  the 
Simplon  road,  from  Geneva  to  Mi- 
lan, which  cost  the  French  Govern- 
ment seventeen  millions  of  livres, 
about  £  650,000. 

Roasting  qf  Iron  Ore  is  either  to 
produce  higher  oxidation,  or  to 
expel  injurious  admixtures.  In 
both  cases,  liberal  access  of  at- 
mospheric air  is  required.  Ore  to 
be  roasted  should  be  broken  into 
pieces  as  small  as  those  usually  put 
into  the  blast-furnace.  The  kind 
of  fuel  required  is  wood,  and  small 
charcoal,  turf  or  peat,  or  brown 
coal,  may  be  used.  There  are  many 
different  forms  of  ovens  used ;  all 
of  them  can  be  reduced  to  that  of 
the  blast-furnace  or  the  lime-kiln. 
These  ovens  are  commonly  from 
twelve  to  eighteen  feet  high,  and 
contain  from  fifty  to  one  hundred 
tons  of  ore  at  one  time. 

Rocking-ahaft,  the  shaft,  with  levers 
on  it,  which  works  the  slide-valves 
in  some  steam  engines.  The  ec- 
centric-rod drops  on  to  a  stud  fixed 
in  one  lever,  and  the  links  of  the 
slide-valve  rod  are  attached  to  the 
opposite  lever  on  the  same  shaft. 
This  mode  of  working  the  slide- 
valves  was  generally  adopted  be- 


ROD 


ROMAN  ARCHITECTURE. 


ROM 


fore  the  introduction,  by  Mr.  Ste- 
phenson, of  the  direct-action  mode 
of  working  them. 

Rod,  ox  pole  J  a  long  measure  of  16^ 
linear  feet,  or  a  square  measure  of 
272^  square  feet 

RolleTf  a  solid  cylinder  of  metal  or 
wood,  used  for  many  purposes 

Rolling  Machine,  an  invention  for 
making  the  brass  mouldings  in 
fenders,  and  the  brass-work  in 
grates 

Rolling  MiU,B,  mill  for  reducing  masses 
of  iron,  copper,  or  other  metals,  to 
even  parallel  bars  or  thin  plates. 
This  is  effected  by  passing  the  me- 
tal, whilst  red-hot,  between  two 
cylindrical  rollers  of  steel,  put  In 
motion  by  the  mill,  and  so  mounted 
in  a  strong  metal  frame  that  they 
cannot  recede  from  each  other. 

RoU-moulding,  a  moulding  used  in 
early  Enghsh  architecture,  resem- 
bling a  roll 

Roman  Architecture,  in  its  masonry, 
both  in  public  and  private  build- 
ings, was  of  far  more  durable  cha- 
racter and  more  accurate  workman- 
ship in  the  earlier  periods  than  at 
the  decline  of  the  empire.  It  began 
with  uncemented  blocks  of  stone, 
passed  into  the  reticulated  work  of 
the  Republic,  thence  into  the  tra- 
vertine, a^d  descended  into  a  mix- 
ture of  tufa  and  brick,  and  stucco 
facing.  The  polyhaedral  wall,  or, 
as  it  is  often  named,  the  Cyclopean, 
is  the  oldest  example  of  masonry 
in  Italy;  but  this  style  of  builds 
ing  has  been  used  in  town  walls 
only. 

Until  about  the  middle  of  the 
last  century,  Roman  architecture 
was  regarded  as  the  Antique  and 
the  Classical  par  excellence,  and 
was  supposed  to  exhibit  the  most 
refmed  taste  and  most  perfect  ar- 
tistic propriety.  The  *  Orders,*  as 
practised  by  the  Romans,  were  the 
examples  taken  up  and  followed  by 
the  Italian  masters  at  the  period  of 
the  so-called  Revival,  and  still  con- 
tinue  to  be  followed,  both  in  that 
country  and  in  France,  in  prefer- 

380 


ence  to  their  Greek  prototypes. 
Among  ourselves,  however,  the 
Roman  style  has  of  late  years  fallen 
somewhat  into  discredit, — at  least 
as  far  as  the  orders  are  concerned, 
— while  some  have  even  gone  fur- 
ther, and  have  censured  the  style 
of  the  Romans  as  being  compara- 
tively rude  and  coarse  in  taste,  and 
their  system  as  being  radically  vi- 
cious and  inconsistent.  Such  is  the 
.opinion  of  both  Mr.  Fergusson  and 
Mr.  Freeman ;  and  the  latter  writer 
further  thinks,  that  '*if  the  mad 
desire  of  imitating  Greece  had  ne- 
ver taken  possession  of  the  Roman 
mind,''  Rome  might,  by  adhering  to 
her  own  previous  mode  of  construc- 
tion with  the  arch  and  vault  alone, 
have  ultimately  wrought  out  a  well- 
organized  style,  greatly  superior 
to  what  she  actually  did  produce, 
and  which  he  pronounces  to  be, 
although  not  without  its  merits, 
''absurd  and  inconsistent  to  the 
last  degree.''  This  almost  unqua- 
lified depreciation  errs,  perhaps, 
nearly  as  much  as  exaggerated  and 
implicit  admiration  had  done  pre- 
viously. 

Nothing,  indeed,  is  to  be  said  in 
favour  of  the  treatment  of  the  two 
Greek  orders  by  the  Romans ;  for, 
strange  to  say,  so  far  from  the 
Doric  acquiring  greater  energy,  or 
the  Ionic  greater  luxuriance,  at 
their  hands,  the  one  was  emasca- 
lated,  the  other  impoverished,  and 
both  of  them  rendered  insipid  and 
characterless.  On  the  other  hand, 
it  is  to  the  Romans  that  we  are  in- 
debted for  almost  all  that  we  know 
of  the  Corinthian  order  as  a  style  ; 
and  it  might,  with  far  greater  pro- 
priety, be  termed  the  Roman  than 
the  Corinthian  one;  for  they  not 
only  greatly  affected  it  and  stamped 
it  as  their  own,  but  frequently 
treated  it  with  singular  gusto. 

As  to  Roman  architecture  gene- 
rally, it  possesses  mechanical  ad- 
vantages and  powers  of  construc- 
tion unknown  to  that  of  the  Greeks, 
and,  owing  to  the  adoption  of  cir- 


ROM 


ROOD-LOFT. 


ROO 


cular  and  other  curved  forms  of 
plan,  possesses  also  a  degree  of  va- 
riety and  piquancy,  if  not  of  highly 
refined  beauty,  that  we  miss  in  the 
other  more  polished  and  correct 
style.  Faulty  as  the  interior  of  the 
Pantheon  is,  in  regard  to  many 
points  of  design,  Greece  could  ne- 
ver show  any  tldng  similar,  much 
less  equal  to  it.  The  exterior,  too, 
of  the  same  edifice  may  be  quoted 
as  affording  an  instance  of  a  correct 
application  of  a  columnar  order  not 
introduced  a^  mere  decoration  be- 
tween arches,  but  applied  as  a 
portico  both  for  actual  use  and  for 
the  sake  of  the  general  effect.  If 
it  be  a  mixed  system,  that  of  the 
Romans  possesses  this  advantage  : 
viz.  it  allows  either  arcading  or 
colonnading  to  be  employed  as  may 
best  accord  with  circumstances, 
whether  in  different  buildings  or 
in  different  parts  of  one  and  the 
same  edifice. 

Perfect  congruity  and  simplicity 
are  not  the  only  valuable  qualities 
in  architecture ;  for  there  is  also  a 
merit  and  a  charm  in  complexity, 
when  diverse,  if  not  contradictory, 
elements  of  construction  and  de- 
sign  are  combined  into  an  harmo- 
nious whole ;  and  the  Romans  ap- 
pear to  have  been  far  more  studious 
of  impressiveness  of  ensemble  than 
of  purity  of  form  and  elegance  of 
detail.  Besides  a  degree  of  vastness 
never  aimed  at  by  the  Greeks, 
sumptuousness  and  picturesqueness 
may  be  said  to  have  been  the  pre- 
dominant characteristics  of  their 
buildings, —  at  least,  of  all  their 
principal  monuments. 

Surely,  then,  we  are  at  liberty  ip 
admire  Rioman  architecture  for  its 
better  qualities,  without  either  be- 
ing blind  to  its  faults  and  defects, 
or  imitating  them,  as  if  they  were 
inseparable  from  its  merits.  Cer- 
tain it  is,  that  in  all  matters  of  de- 
sign and  decoration,  modem  taste 
inclines  infinitely  more  to  that  of 
the  Romans  than  of  the  Greeks. 
Hardly,  too,  can  we  dispense  with 


Roman  taste  and  Roman  ideas,  un- 
less we  can  dispense  with  the  Ita- 
lian style  also :  yet  the  latter  style, 
or  one  founded  upon  it,  must  con- 
tinue to  be  employed  for  our  secu- 
lar buildings,  both  public  and  pri- 
vate, mediaeval  architecture  being 
wholly  out  of  the  question  for 
buildings  generally  at  the  present 
day. 

Roman  balance^  in  mechanics,  the 
steelyard  or  atatera  Romana 

Romanesque  Architecture^  a  name 
given  to  the  style  of  architecture 
which  prevailed  after  the  decline 
of  the  Roman  empire,  from  the 
reign  of  Constantine  till  the  intro- 
duction of  the  pointed  arch 

Roman  white  is  of  the  purest  white 
colour,  but  differs  from  the  blanc 
d'argent  only  in  the  warm  flesh- 
colour  of  the  external  surface  of 
the  large  square  masses  in  which  it 
is  usually  prepared 

Roodf  in  surveying,  the  fourth  part  of 
an  acre  in  square  measure,  or  1210 
square  yards;  a  rod;  a  pole;  a 
measure  of  16^  feet, in  long  measure 

Roodf  or  roode,  a  cross;  a  crucifix 
or  image  of  Christ  on  the  cross, 
placed  in  a  church.  The  holy 
rood  anciently  was  elevated  at  the 
junction  of  the  nave  and  choir, 
and  faced  the  western  entrance  to 
a  church. 

Rood'lqft,  a  gallery  which  was  gene- 
rally placed  over  the  chancel  screen 
in  parish  churches,  and  was  an  ad- 
dition peculiar  to  the  Church  of 
Rome.  The  rood-loft  or  gallery 
had  its  real  support  from  the  tie- 
beams  which  connected  it  with  the 
walls  of  the  building ;  but  in  the 
Decorative  construction  it  appeared 
to  rest  on  a  range  of  arches  or 
mullions  below.  Rood-lofts  are 
formed  both  of  stone  and  wood. 

Rood-tower,  or  steeple^  a  tower  or 
steeple  at  the  intersection  of  the 
nave  and  transept  of  a  church 

Roof,  the  part  above  the  miner's 
head ;  that  part  of  the  strata  lying 
immediately  upon  the  coal 

Roofs,  or  coverings  to  buildings,  are 


SCO 


ROOFS. 


KOO 


▼ariomly  Honned,  both  u  to  mate- 
rials and  ooiwtractioii,  although 
certain  etsential  qualificatioiis  are 
oommon  to  all  of  them.  Thus,  they 
are  required  to  effectuaUy  exclude 
the  weather,  and  at  the  same  time 
impose  the  least  possible  weight 
upon  the  ¥ralls  of  the  buOdings 
over  which  they  are  erected ;  and 
another  purpose  which  they  should 
be  designed  to  effect  is  that  of  aid- 
ing the  walls  in  maintaining  their 
position  by  acting  as  ties  between 
them  at  their  Idghest  and  least 
stable  points.  A  roof  consists 
mainly  of  two  parts,  viz.  the  framing 
or  trussing,  and  the  covering,  the 
width  of  most  buildings  being  too 
great  to  be  spanned  with  any  prac- 
ticable covering  without  the  sup- 
port of  framing  beneath  it.  In 
order  to  avoid  unnecessarily  load- 
ing the  waUs,  the  entire  roof  should 
be  constructed  as  light  as  possible 
consistent  with  safety  and  durabi- 
lity, and  its  several  parts  so  dis- 
posed that  the  weight  shall  fall 
vertically  only  upon  the  walls,  and 
have  no  tendency  to  force  them 
asunder.  In  this  respect,  there- 
fore, the  framing  of  a  roof  is  re- 
quired to  act  entirely  together  as 
the  supporter  of  the  covering,  and 
cannot  be  properly  designed  to  act 
laterally  againat  the  wuls  as  abut- 
ments. Provided  this  condition  is 
secured,  roofs  may  be  formed  so  as 
to  preserve  a  level  upper  surface, 
or  a  ridged  surface,  the  adoption 
of  the  form  depending  upon  the 
occasion  which  may  or  may  not 
exist  for  using  the  exterior  of  the 
roof  as  a  place  of  resort  for  persons 
or  otherwise.  Thus,  in  the  East, 
and  in  warm  climates,  roofs  are  com- 
monly made  flat  on  the  top ;  while 
in  temperate  regions,  exposed  to 
rains,  they  are  usually  ridged,  the 
surface  being  unavailable,  and  the 
escape  of  water  facilitated  by  this 
form. 

Flat  roofs  are  generally  composed 
of  timber  framing,  and  covered 
with  stone  in  large  slabs,  or  with 

382 


artificial  cements,  or  with  concrete 
moulded  in  rectangular  blocks. 
The  timber  framing  in  these  roofs 
consists  of  main  beams  which  span 
the  roof  from  wall  to  wall  in  one 
direction,  and  of  rafios  of  smaller 
scantling  laid  transversely  to  the 
beams,  and  notched  down  upon 
them;  the  distance  between  the 
rafters  being  determined  by  the 
size  of  the  covering  blocks  or 
slabs.  * 

Ridged  rooft  are  composed  of 
framings  of  wood,,  malleable  iron, 
or  cast  iron,  and  coverings  of  tiles 
of  burnt  day  in  various  forms,  of 
slate,  of  iron  in  rolled  sheets  or 
cast  plates,  of  copper  or  lead  in 
sheets.  Each  frame  of  the  roof  is 
termed  a  truu,  and  consists  of  se- 
veral members,  according  to  the 
width  of  the  truss  or  span  of  the 
roof. "  The  principal  of  these  mem- 
bers, in  a  wooden  truss,  are,  the 
tte-beatn,  which  equals  in  length 
the  span  of  the  roof,  and  is  laid 
horizontally  across  the  building, 
resting  at  each  end  upon  a  waU- 
plate  of  timber,  a  cast-iron  shoe, 
or  a  stone  template ; — i\it  principal 
rafters^  which  are  two  timbers  of 
equal  length,  framed  into  the  ends 
of  the  tie-beam,  and  meeting,  in 
the  manner  of  the  legs  of  an  isos- 
celes triangle,  in  a  point  equidis- 
tant from  the  ends  of  the  tie-beam 
and  at  some  height  above  its  cen- 
tral point.  The  apex  of  the  tri- 
angle or  ridge  of  the  roof  is  sup- 
ported by  a  vertical  post,  called  the 
kinff'postf  properly  framed  and  se- 
.  cured  to  the  Ikcads  of  the  rafters 
and  to  the  tie-beam.  The  two  tri- 
angular spaces  thus  formed  be- 
tween the  rafters,  tie-beam,  and 
king-post  are  filled  in  with  other 
members,  according  to  the  size  of 
the  truss,  and  adapted  to  assist  the 
rafters  in  bearing  the  weight  of  the 
covering,  and  to  connect  each 
rafter  with  the  half  of  the  tie-beam 
below  it  in  a  firm  and  substantial 
manner.  In  roofs  of  small  span, 
these  additional  members  are  sim- 


ROO 


ROPE  MACHINERY. 


ROP 


ply  two  struts  fixed  in  a  diagonal 
position  from  the  bottom  of  the 
king-post   on  either  side  to  the 
middle  of  the  length  of  each  rafter. 
In  larger  roofs  the  requisite  strength 
is  attained,  and  a  space  saved  in 
the  roof  (available  as  a  dormitory 
or  store-room),  by  introducing  two 
vertical  posts,  termed  queen-posts, 
leaving  a  space  in  the  centre  of  the 
roof  between  them,  these  queen- 
posts  being  secured  by  straps  below 
to  the  tie-beam,  and  bearing  the 
rafters  above.    A  horizontal  beam 
connects  the  heads  of  the  queen- 
postSy  and   is   termed    a    cottar^ 
deam,  the  -centre  of  which  is  se- 
cured to  a  king-post,  which  sup- 
ports the  heads  of  the   principal 
rafters  and  the  ridge  of  the  roof. 
Diagonal  struts  are  framed  in  be- 
tween the  rafters  and  the  king- 
posts and  queen-posts,  and  thus 
complete  the  truss.    The  trusses 
are  fixed  at  intervals,  from  7  to  12 
feet  apart,  throughout  the  length 
of  the  roof,  and  upon  their  princi- 
pal rafters    longitudinal    timbers, 
called  purlins,  are  notched  down, 
and    carry  the    common    rafters, 
which  are  of  minor  scantling,  fixed 
parallel  to  the  principal  rafters,  at 
small  distances  apart.    According 
to  the  kind  of  covering  to  be  used, 
thin  strips  of  wood,  called  battens, 
are  secured  to  the  common  rafters, 
and  upon  these  the  slates,  tiles,  &c. 
are  secured  with  pegs,  or  copper 
nails. 

Iron  roofs,  which  are  much  su- 
perior to  those  of  timber,  especially 
for  ^ge  spans,  from  their  light- 
ness and  resistance  to  fire,  are 
composed  of  the  same  essential 
members  as  those  here  described, 
malleable  rods  or  flat  bars  being 
substituted  for  the  tie-beams  and 
king.posts,  and  the  rafters  and 
struts  made  of  sufficient  stiffness 
with  bars  of  malleable  L  or  T-iron, 
or  with  cast  iron  of  suitable  form 
and  section.  In  these  roofs  all  the 
meeting.points  of  the  several  parts 
of  each  truss  or  principal  are  pro^ 

383 


vided  with  cast-iron  shoes,  sockets, 
and  connecting-plates,  into  which 
the  ends  of  the  rafters,  struts,  and 
rods  are  secured  with  screwed  bolts 
and  nuts,  or  gibs  and  keys. 

Boom  and  space,  the  distance  from 
the  joint  or  moulding  edge  of  one 
floor  timber  to  the  other,  which,  in 
all  ships  that  have  ports,  should  be 
so  disposed  that  the  scantling  of 
the  timber  of  each  side  of  the  port, 
and  the  breadth  of  the  port  fore 
and  aft  (the  openings  between  the 
timbers  of  the  frames,  if  any,  in- 
cluded), be  answerable 

Root,  in  arithmetic  and  algebra,  de- 
notes a  quantity  which,  being  mul- 
tiplied by  itself,  produces  some 
higher  power 

Rope,  twisted  hemp  or  wire,  used  in  all 
kinds  of  buildings,  for  the  manage- 
ment and  control  of  building,  for 
the  construction  of  bridges,  and 
on  board  ship;  it  is  a  species  of 
tackle  inseparable  from  the  arts 

Rope  Machinery,  The  simple  and 
beautiful  contrivance  employed  in 
the  dockyards  for  this  most  useful 
material,  is  contrived  by  machinery 
for  the  spinning  of  hemp  into 
yams,  and  the  final  preparation  of 
the  same  into  ropes  and  cables  for 
the  navy.  The  process  first  em- 
ployed is  separating  the  fibres  from 
the  hemp,  and  disposing  them  as 
nearly  as  possible  into  parallel  jux- 
taposition ;  then  the  conversion  of 
these  bundles  of  parallel  fibres  into 
a  flattened  ribband-like  form  called 
a  sliver,  and  the  spinning  of  this 
sliver  into  a  yam,  or  simple  twist. 
In  a  valuable  treatise  in  vol.  ,v.  of 
the  *  Papers  of  the  Royal  Engi- 
gineers,'  will  be  found  illustrative 
plates  of  the  machinery  employed 
in  this  operation  in  Deptford  dock- 
yard, together  with  an  elaborate 
description. 

Rosary,  an  office  in  the  Church  of 
Rome  made  up  of  five  or  fifteen 
tens  of  beads,  each  ten  beginning 
with  a  Pater-noster,  to  direct  them 
to  say  so  many  Ave  Maria's  in 
honour  of  the  Virgin  Mary 


r 


ROS 


ROTARY  MOTION. 


RUB 


Rose  Pink  is  a  coarse  kind  of  lake, 
produced  by  the  dyeing  of  chalk  or 
whiting  with  a  decoction  of  Bra- 
zil wood,  &c.  It  is  a  pigment 
much  used  by  paper-stainers  and 
in  the  commonest  distemper  paint- 
ings, &c.,  but  too  perishable  to 
merit  the  attention  of  artists. 

Rosetta  wood  is  a  good-sized  East 
Indian  wood,  imported  in  logs,  9 
to  14  inches  diameter ;  it  is  hand- 
somely veined.  The  general  colour 
is  a  lively  red  orange.  The  wood 
is  close,  hard,  and  very  beautiful 
when  first  cut,  but  soon  gets 
darker. 

Rose  window^  a  circular  window 

Rose-wood  is  produced  in  the  Brazils, 
the  Canary  Isles,  the  East  Indies, 
and  Africa.  It  is  imported  in  very 
large  slabs,  or  the  halves  of  trees, 
that  average  18  inches  wide.  The 
colours  of  rose-wood  are  from  light 
hazel  to  deep  purple,  or  nearly 
black;  the  tints  are  sometimes 
abruptly  contrasted,  at  other  times 
striped  or  nearly  uniform.  It  is 
very  heavy,  and  most  abundantly 
used  for  cabinet  furniture :  large 
quantities  are  frequently  cut  for  use 
in  veneers. 

Rostrum^  the  elevated  platform  or 
stage  in  the  forum  of  ancient 
Rome,  from  which  the  orators 
addressed  the  people :  a  platform 
in  a  hall  or  assembly 

Rotary  motion^  the  rotation  or  mo- 
tion of  any  body  round  an  axis  or 
centre :  the  velocity  of  this  motion 
of  bodies  is  proportional  to  their 
distance  from  such  centre 

Rottbnda^  in  architecture,  an  appella- 
tion given  to  any  building  that  is 
round  both  within  and  without  side, 
whether  it  be  a  church,  saloon, 
theatre,  &c.  The  rotunda  at  Rome, 
called  the  Pantheon,  and  the 
chapel  of  the  Escurial,  the  burying- 
place  of  Spanish  royalty,  &c.,  are 
of  this  form. 

Rouge.  The  rouge  vegetale  of  the 
French  is  a  species  of  carmine  pre- 
pared from  safflow,  of  exquisite 

beauty  and  great  cost.     Its  prin- 
_ 


cipal  uses  consist  in  dyeing  dlks 
of  rose  colours,  and  in  combining 
with  levigated  talc  to  form  the 
paint  of  the  toilette,  or  cosmetic 
colours  employed  by  the  fair. 

RougJicastf  in  building,  a  kind  of 
plaster  mixed  with  pebbles,  •  and 
consequently  rough  on  the  surface 

Roundhousef  the  uppermost  deck  in 
a  ship  abaft,  sometimes  called  the 
poop 

Royal  Blue  h  a  deep-coloured  and 
beautiful  smalt,  and  is  also  a  vit- 
reous pigment,  principally  used  in 
painting  on  glass  and  enamelling, 
in  which  uses  it  is  very  permanent ; 
but  in  water  and  oil  its  beauty  soon 
decays,  as  is  no  uncommon  case 
vtrith  other  vitrified  pigments  ;  it 
is  not  in  other  respects  an  eligible 
pigment,  being,  notvidthstanding 
its  beautiful  appearance,  very  infe- 
rior to  other  cobalt  blues. 

Rubble,  coarse  walling  constructed  of 
rough  stones,  small,  irregular  in 
size  and  shape ;  a  mixture,  or  the 
refuse  of  several  kinds  of  building- 
stone  used  for  walls  exteriorlj,  or 
between  walls,  to  fill  up 

Rumens'  Brown.  The  pigment  still  in 
use  in  the  Netherlands  under  this 
appellation  is  an  earth  of  a  lighter 
colour  and  more  ochreous  texture 
than  the  Vandyke  brown  of  the 
London  shops ;  it  is  also  of  a 
warmer  or  more  tawny  hue  than 
the  latter  pigment,  and  is  a  beau- 
tiful and  durable  brown,  which 
works  well  both  in  water  and  oil, 
and  much  resembles  the  brown 
used  by  Teniers. 

Rubric,  or  Madder  Lakes.  These  pig- 
ments are  of  various  colours,  and 
are  known  by  the  various  names  of 
rose,  rubiate,  rose  madder,  pink 
madder,  and  Field's  lakes. 

Rudder,  the  principal  matter  which 
guides  the  ship.  The  main-piece 
and  the  bearding-piece  are  always 
oak,  and  the  rest  generally  fir.  The 
rudder  should  be  bearded  from  the 
side  of  the  pintles,  and  the  fore-aide 
made  to  the  form  of  the  pintles; 
but  when  they  are  bearded  to  a 


RUD 


SAFETY-PLUG. 


SAP 


sharp  edge  at  the  middle  line, 
which  is  the  customary  way,  it 
redaces  the  main-piece  more  than 
is  necessary,  which  is  easily  per- 
ceived in  large  ships ;  for  when  the 
rudder  is  braced  over,  the  beard- 
ing will  not  lie  close  to  the  stem- 
post  by  nearly  }  of  an  inch. 

Rudder  ironst  or  pintlest  the  irons 
which  are  fastened  to  the  rudder 
in  order  to  hang  it  up  to  the  stem- 
post  :  sometimes  there  are  two  of 
them  cut  short  to  work  in  a  socket 
in  the  brace,  which  makes  the 
rudder  work  easier 

Rudenture,  in  architecture,  the  figure 
of  a  rope  or  staff,  sometimes  plain, 
sometimes  carved,  with  which  the 
third  part  of  the  flutings  of  columns 
are  frequently  filled  up 

Ruderatum^  in  building,  a  term  used 
by  Vitruvius  for  laying  of  pavement 
with  pebbles.  To  perform  the 
ruderation  it  is  necessary  that  the 
ground  be  well  beaten,  to  make  it 
firm,  and  to  prevent  it  from  crack- 
ing ;  then  a  stratum  of  little  stones 
is  laid,  to  be  afterwards  bound 
together  with  mortar  made  of  lime 
and  sand :  if  the  sand  be  new,  its 
proportion  may  be  to  the  lime  as 
three  to  one;  if  dug  out  of  old 
pavements  or  from  walls,  as  five  to 
two. 

Running-rigging f  in  navigation,  de- 
notes all  that  portion  of  a  ship's 
rigging  which  passes  through  the 
blocks,  to  dilate,  contract,  or  tra- 
yerse  the  sails 

Rustetf  Rubiate,  Madder  Brown,  or 


SAC 

Sacellum,  a  monumental  chapel 
within  a  church 

Sacrariumy  a  small  family  chapel  in 
a  Roman  house;  a  place  for  the 
deposit  of  any  thing  sacred 

Sacristy,  a  room  attached  to  a  church, 
where  the  sacred  vestments  and  the 
utensils  belonging  to  the  altars 
were  placed ;  termed  also  the  sex- 
try,  the  vestry,  &c. 

385 


Fields  Russet,  is,  a  sits  names  indi- 
cate, prepared  from  the  rubia  tine- 
toriUi  or  madder  root.  It  is  of  a 
pure,  rich,  transparent,  and  deep 
rasset  colour,  of  a  tme  middle  hue 
between  orange  and  purple,  not 
subject  to  change  by  the  action  of 
light,  impure  air,  time,  or  mixture 
of  other  pigments.  It  has  supplied 
a  great  desideratum,  and  is  indis- 
pensable in  water-colour  painting, 
both  as  a  local'  and  auxQiary  co- 
lour, in  compounding  and  pro- 
ducing with  yellow  the  glowing  hues 
of  autumnal  foliage,  &c.,  and  with 
blue  the  beautiful  and  endless 
variety  of  aerial  grays. 

Rustication,  the  general  name  for 
that  species  of  masonry  in  which 

'  the  several  courses  of  the  stontis  in 
each  course  are  distinctly  marked 
by  sunk  joints  or  grooves,  either 
chamfered  or  otherwise  cut.  Rus- 
tication admits  of  great  variety  of 
treatment,  consequently  of  expres- 
sion also;  for,  quite  contrary  to 
what  its  name  literally  imports,  it 
is  frequently  made  to  show  the 
very  reverse  of  careless  rudeness, 
namely,  studied  ornamentation,  by 
means  of  highly  finished  moulded 
joints,  &c. ;  and  even  when  the 
faces  of  the  rustics  or  stones  are 
vermictdated,  or  otherwise  made 
rough,  it  is  left  to  be  seen  that  it 
is  done  purposely  or  artificially, 
more  especially  when  the  vermicu- 
lation,  &c.,  is  made  to  show  a  sort 
of  panel  surrounded  by  a  smooth 
border. 


SAF 

Saddle,  in  ship-building,  a  piece  fitted 
on  the  upper  end  of  the  lacing 

Safety 'lamp,  a  wire-gauze  lamp,  con- 
stracted  for  the  purpose  of  giving 
light  in  mines  where  fire-damp 
prevails 

Safety-plug,  in  locomotive  engines,  a 
bolt  having  the  centre  filled  with 
a  fusible  metal.  It  is  screwed  into 
the  top  of  the  fire-box,  that  the 


SAF 


SANDAL  WOOD. 


SAN 


metal  may  melt  out  by  the  in- 
creased temperature  when  the 
water  becomes  too  low,  and  thus 
admit  the  water  to  put  the  fire 
out,  and  save  the  tubes  and  fire- 
box. When  the  water  is  allowed 
to  fall  below  a  proper  height,  there 
is  great  ri^k  of  spoiling  both  the 
fire-box  and  tu1)es  by  the  intense 
action  of  the  fire.  This  is  called 
'burning  them;'  and  tubes  sub- 
jected  to  such  a  trial  are  unfit  for 
use  again,  as  the  tenacity  of  the 
metal  has  been  destroyed. 

Safety-vahes,  in  locomotive  engines, 
two  valves  placed  on  the  boiler  for 
the  escape  of  steam  when  it  ex- 
ceeds the  pressure  limited  by  the 
load  on  these  valves.  One  of  them 
is  placed  beyond  the  control  of  the 
engine-man,  and  is  usually  called 
the  lock-up  vaJne,  The  other  is 
regulated  by  a  lever  and  spring- 
balance,  at  a  little  lower  pressure 
than  the  lock-up  valve.  The  aper- 
tures for  safety-valves  require  no* 
nice  calculation.  It  is  only  neces- 
sary to  have  the  aperture  sufficient 
to  let  the  steam  off  from  the 
boiler  as  fast  as  it  is  generated, 
when  the  engine  is  not  at  work. 
The  safety-valve  is  loaded  some- 
times by  putting  a  heavy  weight 
upon  it,  and  sometimes  by  means 
of  a  lever  with  a  weight  to  move 
along  to  suit  the  required  pressure. 

Scfety-vahe  lever,  in  locomotive  en- 
gines, the  lever  fixed  at  one  end  to 
a  stud,  and  resting  on  the  valve  at 
a  short  distance  from  this  stud. 
Its  length  is  proportioned  to  the 
area  of  the  valve,  so  that  the  spring- 
balance  may  indicate  accurately  the 
pressure  In  tbs.  per  square  inch  on 
the  boiler,  above  the  atmosphere. 

Sagging,  in  ship-building,  a  term  the 
reverse  of  hogging,  being  applied 
to  the  hull  of  a  ship  when  the 
middle  part  of  her  keel  and  bottom 
arch  downwards 

Sagitta,  in  architecture,  a  name 
sometimes  used  for  the  key-piece 
of  an  arch 

Sailing,  plain,  in  navigation,  is  that 

386 


which  is  performed  by  means  of  a 
plane  chart,  in  which  the  parallels 
of  latitude  and  longitude  are  every 
where  equal 

Sainti*  bell,  a  small  bell  used  in  the 
Roman  Catholic  worship,  to  call 
attention  to  the  more  solemii  parts 
of  the  service 

Salt-cellars,  in  Tudor  times,  were 
pieces  on  which  the  taste  and  fancy 
of  goldsmiths  were  severely  exer- 
cised. These  artists  were  held  in 
high  estimation,  and  ranked  with 
architects  andsculptora.  Benvenuto 
Cellini,  in  the  time  of  Henry  VII., 
was  the  greatest  designer  and 
chaser,  or  sculptor  in  gold  and 
silver,  in  Europe :  he  visited  Eng- 
land at  this  period,  and  excit^ 
much  attention. 

Sanctum  Sanctorum,  or  holy  of  holies, 
the  most  sacred  part  of  the  temple 
of  Jerusalem,  containing  the  ark  of 
the  covenant 

Sanctuary,  the  presbytery  or  eastern 
part  of  the  choir  of  a  church  in 
which  the  altar  is  placed 

Sand  is  the  term  applied  to  any  mi- 
neral substance  in  a  granular  state, 
.  where  the  grain  is  of  an  appreciable 
size,  and  insoluble  in  water.  It 
is  more  particularly  denominated 
from  the  prevailing  substance,  as 
silicious  sand,  iron  sand,  &c  Sand 
is  of  general  use  for  the  mixing  of 
material  in  building :  river  sand  is 
far  preferable. 

Sand'boxet,  in  locomotive  engines, 
boxes  filled  with  sand,  usually 
placed  near  the  driving  wheels, 
with  a  pipe  to  guide  the  sand  to  the 
rails,  to  be  used  when  slipping 
takes  place 

Sandstone,  a  soft  porous  kind  of 
stone,  generally  known  by  the  name 
of  free-stone.  It  is  composed  of 
small  particles  of  quartz  in  rounded 
grains,  united  by  an  argillaceous  or 
calcareous  cement. 

Sandal  wood,  a  tree  having  somewhat 
the  appearance  of  a  larg^  myrtle. 
The  wood  is  extensively  employed 
as  a  perfume  in  the  funereal  cere- 
monies of  the  Hindoos.  The  deeper 


SAN 


SATIN  WOOD. 


SAU 


the  colour,  which  is  of  a  yellow 
brown,  and  the  nearer  the  root, 
the  better  is  the  perfume.  It  is 
imported  in  trimmed  logs  from  3 
to  8,  and  rarely  14  inches  in  dia- 
meter, and  the  wood  is  in  general 
softer  than  box-wood,  and  easy  to 
cut :  it  is  used  for  parts  of  cabinets, 
necklaces,  ornaments,  and  fans. 

Sanitary  PreeautiotUf  for  London  in 
its  southern  district,  were  discussed 
nearly  half  a  century  since.  Ralph 
Dodds,  an  eminent  engineer  of  that 
period,  writes,  in  his  exhortation  for 
a  better  supply  of  pure  water,  the 
following.  "  I  cannot  help  noticing 
that  part  of  the  south  metropolis, 
St.  George's  Fields,  lies  4  or  5  feet 
below  the  flow  of  high  water,  and 
is  sobadly  drained,  and  I  may  say,  so 
saturated  with  filthy  water,  with 
other  deposits  of  every  species  of  dirt 
and  filth  from  the  City  and  South- 
wark,thatit  must  be  the  firstplaceto 
invite  pestilence,  should  it  ever  be 
generatedinthis  part  of  the  country. 
I  hope  this  will  meet  the  eye  of 
those  who  wait  only  for  information 
to  improve  its  situation.'' 

&i/»an  wood,  or  buekum  wood,  is  a 
middle-sized  tree,  indigenous  to 
Siam,  Pigo,  &c. :  for  purposes  of 
dyeing  it  is  inferior 

Sap-green,  or  Verde  Veerie,  is  a  vege- 
table pigment  prepared  from  the 
juice  of  the  berries  of  the  buck- 
thorn, the  green  leaves  of  the  wood, 
the  blue  flowers  of  the  iris,  &c. : 
it  is  usually  preserved  in  bladders, 
and  is  thence  sometiines  called 
bladder  green ;  when  good,  it  is  of 
a  dark  colour  and  glossy  fracture, 
extremely  transparent,  and  of  a 
flne  natural  green  colour.  Though 
much  employed  as  a  water  colour 
without  gum,  which  it  contains 
naturally,  it  is  a  very  imperfect 
pigment,  disposed  to  attract  the 
moisture  of  the  atmosphere  and  to 
mildew;  and  having  little  durability 
in  water-colour  painting,  and  less 
in  oil,  it  is  not  eligible  in  the  one, 
and  totally  useless  in  the  other. 
I  Sapphire,  a  pellucid  gem,  which  in  its 

387 


flnest  state  is  extremely  beautiful 
and  v^uable,  and  inferior  only  to 
the  diamond  in  lustre,  hardness, 
and  value.  Its  proper  colour  is 
pure  blue ;  in  the  finest  specimens 
it  is  of  the  deepest  azure,  and  in 
others  it  varies  into  paleness,  in 
shades  of  all  degrees  between  that 
of  a  pure  crystal  brightness  and 
water  without  the  least  tinge  of 
colour,  but  with  a  lustre  much  su- 
perior to  the  crystal.  The  gem 
known  to  us  by  this  name  differs 
greatly  from  the  sapphire  of  the 
ancients,  which  was  only  a  semi- 
opaque  stone  of  a  deep  blue,. veined 
vrith  white,  and  spotted  with  small 
gold-coloured  spangles  in  the  form 
of  stars. 

Saracenic  Architectwre  is  a  species  of 
architecture  derived  by  the  Eu- 
ropeans from  the  Arabs,  or  Sara- 
cens, during  the  crusades 

Sarcophagus,  a  stone  coflin  or  grave 
in  which  the  ancients  laid  those 
they  had  not  a  mind  to  bum 

Sashf  a  chequred  frame  for  holding 
the  squares  of  glass  in  windows, 
and  so  formed  as  to  be  let  up  and 
down  by  means  of  piflleys  inserted, 
or  other  contrivances.  The  ordi- 
nary sashes  are  either  single  or 
double  hung. 

Sassafras  wood  is  a  species  of  laurel, 
and  the  root  is  used  in  medicine:  it 
measures  from  4  to  12  inches  in 
diameter.  It  is  sometimes  used 
for  cabinet-work  and  turnery. 

Saiin  wood.  The  best  variety  is  the 
West  Indian,  imported  from  St. 
Domingo  both  in  square  logs  and 
planks,  from  9  to  20  inches  wide. 
The  next  in  quality  is  the  East 
Indian,  logs  from  9  to  30  inches 
diameter.  The  wood  is  close,  not 
so  hard  as  box-wood,  but  some- 
what like  it  in  colour,  or  rather 
more  orange ;  some  pieces  are  very 
beautifully  mottled  and  curled.  It 
is  much  used  for  internal  decora- 
tions  and  furniture.  It  is  also 
used  for  many  other  purposes  for 
its  light  and  agreeable  tone. 

Saucers,  small  deep  dishes,  for  sauces, 


SAU 


SAXON  STYLE. 


SAX 


&C.,  and  also  used  as  stands  for 
yases,  and  other  vessels  filled  with 
wines,  to  prevent  the  liquor  being 
spilt  upon  the  table.  In  the  reign 
of  Elizabeth,  dishes  and  platters, 
which  before  her  time  were  quite 
flat,  began  to  assume  their  present 
form. 

Saul  or  Sdl,  an  East  Indian  timber- 
tree.  TMs  wood  is  in  very  general 
use  in  India  for  beams,  rafters,  and 
various  building  purposes;  is  close- 
grained  and  heavy,  of  a  light  brown 
colour,  not  so  durable  but  stronger 
than  teak,  and  is  one  of  the  best 
timber-trees  of  India. 

Sounder^  Blue  (a  name  corruptedfrom 
cendret-bleu)f  the  original  deno- 
mination  probably  of  ultramarine 
ashes,  is  of  two  Idnds,  the  natural 
and  the  artificial.  The  artificial  is 
a  verditer,  prepared  by  lime  or  an 
alkali,  from  nitrate  or  sulphate  of 
copper.  The  natural  is  a  blue 
mineral,  found  near  copper  mines, 
and  is  the  same  as  mountain-blue. 

Satfff  a  toothed  instrument  which 
serves  to  cut  into  pieces  several 
solid  matters,  as  wood,  stone,  ivory, 
&c.  The  best  saws  are  of  tem- 
pered steel,  ground  bright  and 
smooth ;  those  of  iron  are  hammer- 
hardened  :  hence  the  first,  besides 
their  being  stifier,  are  likewise 
found  smoother  than  the  last. 
They  are  known  to  be  well  ham- 
mered by  the  stiff  bending  of  the 
blade,  and  to  be  well  and  evenly 
ground  by  their  bending  equally 
in  a  bow.  The  edge  in  which 
are  the  teeth  is  always  thinner 
than  the  back,  because  the  back  is 
to  follow  the  edge.  The  teeth  are 
cut  and  sharpened  with  a  triangular 
file,  the  blade  of  the  saw  being  first 
fixed  in  a  whetting-block. 

SawfilCf  a  triangular  file  for  sharp- 
ening a  saw 

Saw  Mills,  The  very  ingenious  ma- 
chinery constructed  by  the  late 
Mr.  Henry  Maudslay  is  employed 
in  the  dockyards  to  saw  timber,  and 
for  cutting  deals  and  the  several 
kinds  of  timber  used  in  the  navy 

388 


and   in  public   works,    into    the 
several  scantlings,  sizea,  forms,  or 
shapes.    In  vol.  vi.  of  the  '  Papers 
of  the   Royal  Engineers'  will  be 
found  a  most  ample  statement  of 
the  processes  for  sawing,  and  cat- 
ting, and  hoisting,  by  steam  power, 
in  Chatham  dock,  together  with 
engravings    illustrative    of    eveiy 
operation  in  these  works. 
Saxon  Style  of  Architecture.     This 
is  easily  recognized  by  its  massive 
columns  and  semicircular  arches, 
which  usually  spring  from  capitals 
without  the  intervention  of  the  en- 
tablature. In  the  first  Saxon  build- 
ings, the  mouldings  were  extremely 
simple,  the  greater  part  consisting 
of  fillets  and  plat-bands,  at  right 
angles  to  each  other,  and  to  the 
general  surfisce.     The    archivolts 
and  imposts  were  similar  to  those 
found  in   Roman    edifices.      The 
general  plans  and  disposition  of 
the  latter  Saxon  churches  were  as 
follow:  the  chief  entrance  was  at 
the  west  end  into  the  nave,  at  the 
upper  end  of  which  was  a  cross, 
with  the  arms  of  it  extending  north 
and  south  ;  the  east  end,  contain- 
ing the  choir,  terminated    in   a 
semicircular  form.    A  tower  wras 
erected   over  the  centre    of  the 
cross,  and  to   contain  the    bells 
another  was  frequently  added,  and 
sometimes  two.  The  large  churches 
contained  a  nave  and  two    side 
aisles,  one  on  each  side  of  the  nave, 
and  were  divided  into  three  tiers 
or  stories,  the  lower  consisting  of 
a  range  of  arcades  on  each  side, 
the  middle  a  range   of  galleries 
between  the  roof  and  vaulting  of 
the  aisles,  and  the  uppermost  a 
range  of  windows.     The    pillars 
were  either  square,  polygonal,  or 
circular.     Such  was  the  thickness 
of  the  walls  and  pillars,  that  but- 
tresses were  not  necessary,  neither 
were  they  in  use.     The  apertures 
were  splayed  frrom  the  mullions  on 
both  sides.     The    dressings    are 
generally  placed  on  the  sides  of 
the  splayed  jambs  and  heads  of  the 


SCA 


SCARLET  LAKE. 


SCA 


arches,  and  but  seldom  against  the 
face  of  the  walls ;  and  when  this 
is  the  case,  the  projectures  are  not 
very  prominent.  The  dressings  of 
the  jambs  frequently  consist  of  one 
or  several  engaged  columns  upon 
each  side.  The  imposts,  parti- 
cularly  those  of  the  windows,  have 
frequently  the  appearance  of  being 
a  part  of  the  wall  itself.  The  doors 
in  general  were  formed  in  deep  re- 
cession, and  a  series  of  equidistant 
engaged  columns  placed  upon  each 
jamb,  and  were  such,  that  two 
horizontal  straight  lines  would  pass 
through  the  axis  of  each  series, 
and  would,  if  produced,  terminate 
in  a  point.  Each  coliunn  is  at- 
tached to  a  recess  formed  by  two 
planes,  constituting  an  interior 
right  angle.  The  angle  at  the 
meeting  of  every  two  of  these  re- 
cesses formed  an  exterior  right 
angle,  which  was  sometimes  ob- 
tunded,  and  frequently  hollowed. 
The  archivolts,  resting  on  the 
capitals  of  the  columns,  are  formed 
on  the  soffit  shelving,  like  the 
jambs  below.  The  ornaments  of 
columns  and  mouldings  are  of  very 
simple  forms.  The  rudely  sculp- 
tured figures,  which  often  occur  in 
door  cases,  when  the  head  of  the 
door  itself  is  square,  indicates  a 
Roman  original,  and  are  mostly 
referable  to  an  era  immediately 
preceding  the  Conquest. 

Scabellunif  in  ancient  architecture,  a 
kind  of  pedestal,  commonly  ter- 
minating in  a  sort  of  sheath  or 
scabbard,  used  to  support  busts,  &c. 

Scagliola,  in  the  arts,  a  composition, 
an  imitation  of  marble,  laid  on 
brick  in  the  manner  of  stucco,  and 
worked  off  with  iron  tools 

ScalOf  a  ladder,  a  staircase,  from  Scala 
Santa,  a  building  at  Rome,  erected 
from  the  designs  of  Fontana,  with 
three  flights  of  stairs.  The  build- 
ing is  so  called  because  the  middle 
flight  consists  of  twenty-eight  steps, 
said  to  have  been  passed  over  by 
our  Saviour  in  his  progress  to  the 
house  of  Pilate.     They  were  sent 

389 


from  Jerusalem  to  Rome  by  St. 
Helena,  and  are  objects  of  reve- 
rence to  Roman  Catholic  pilgrims. 

Scale,  in  painting,  a  figure  subdivided 
by  lines  like  a  ladder,  which  is  used 
to  measure  proportions  between 
pictures  and  the  things  represented 

ScamiUus,  a  small  plinth  below  the 
bases  of  Ionic  and  Corinthian  co- 
lumns 

ScantUngy  the  transverse  dimensions 
of  a  piece  of  timber  in  breadth  and 
thickness 

Scantling  is  also  the  name  of  a  piece 
of  timber,  as  of  quartering  for  a 
partition,  or  the  rafters,  purlin,  or 
pole-plate  of  a  roof.  All  quartering 
under  five  inches  is  termed  scant- 
ling. 

Scantling,  in  masonry,  the  size  of  the 
stones  in  length,  breadth,  and  thick- 
ness 

Scapple :  to  scapple  a  stone  is  to  re- 
duce it  to  a  straight  surface  with- 
out working  it  smooth 

Scarcement,  a  plain  flat  set  off  in  a 
wall 

Scaptu,  in  architecture,  the  shaft  of 
a  column.  In  botany,  a  flower- 
stalk  springing  straight  from  the 
root,  as  in  the  primrose,  snow- 
drop, &c. 

Scarf f  to  lap  the  ends  of  plank  or 
timber  one  over  the  other,  to  ap- 
pear as  one  solid  piece,  as  keel- 
pieces,  clamps,  &c. 

^Scatfed,  in  carpentry,  signifies  pieced 
or  joined,  being  a  particular  method 
of  uniting  two  pieces  of  timber  by 
their  extremities 

Scarfingy  the  junction  of  two  pieces 
of  timber  by  being  bolted  or  nailed 
transversely  together,  so  that  the 
two  appear  as  one 

Scarlet  Lake  is  prepared  in  form  of 
drops  from  cochineal,  and  is  of  a 
beautiful  transparent  red  colour 
and  excellent  body,  working  well 
both  in  water  and  oil,  though,  like 
other  lakes,  it  dries  slowly.  Strong 
light  discolours  and  destroys  it, 
both  in  water  and  oil;  and  its  tints 
.with  white  lead,  and  its  combi- 
nations with  other  pigments,  are 


SCA 


SCREEN. 


SCR 


not  permanent;  yet  when  well  pre- 
pared and  judiciously  used  in  suffi- 
cient body,  and  kept  from  strong 
light,  it  has  been  known  to  last 
many  years ;  but  it  ought  never  to 
be  employed  in  glazing,  nor  at  all 
in  performances  that  aim  at  high 
reputation  and  durability. 

Scarp,  in  heraldry,  signifies  the  scarf 
worn  by  military  commanders 

Scena,  the  permanent  architectural 
front  which  faced  the  audience  part 
of  a  Roman  theatre :  it  sometimes 
consisted  of  three  several  ranges  of 
columns  one  above  another 

Seenography,  in  perspective,  the  re- 
presentation of  a  body  on  a  per- 
spective plane;  adescriptionthereof 
in  all  its  dimensions,  such  as  it  ap- 
pears to  the  eye 

Schola,  the  margin  or  platform  sur- 
rounding a  bath.  It  was  occu- 
pied by  those  who  waited  until  the 
bath  was  cleared.  The  schola  was 
also  a  portico  corresponding  to  the 
exedra  of  the  Greek  palaestra,  and 
was  intended  for  the  accommo- 
dation of  the  learned,  who  were 
accustomed  to  assemble  and  con- 
verse there. 

Schools  of  Painting.  A  school  in  the 
fine  arts  denominates  a  class  of 
artists  who  have  learned  their  art 
from  a  certain  master,  either  by 
receiving  his  instruction  or  by 
studying  his  works,  and  who  of 
consequence  discover  more  or  less 
of  his  manner  from  the  desire  of 
imitation,  or  from  the  habit  of 
adopting  his  principles.  All  the 
painters  which  Europe  has  pro- 
duced since  the  renovation  of  the 
arts  are  classed  under  the  following 
Schools:  the  School  of  Florence, 
the  School  of  Rome,  the  School  of 
Venice,  the  Lombard  School,  the 
French  School,  the  German  School, 
the  Flemish  School,  the  Dutch 
School,  the  Spanish,  and  the  Eng- 
lish School. 

Schooner,  in  navigation,  a  small  two- 
masted  vessel  whose  mainsail  and 
foresail  are  suspended  from  gaffs 
and  stretched  out  below  by  booms 

agcT 


Schweinfiirt  Blue  appears  to  be  the 
same  in  substance  as  Scheie's 
green,  prepared  without  heat,  or 
treated  with  an  alkali.  It  is  a  beau- 
tiful colour,  liable  to  the  same 
changes  and  is  of  the  same  habits 
as  blue  verditer,  and  the  above  in- 
eligible pigment. 

Sciagraphy,  in  architecture,  the  pro- 
file or  section  of  a  building,  to 
show  the  inside  thereof.  In  astro- 
nomy, the  art  of  finding  the  hour 
of  the  day  or  night  by  the  shadow 
of  the  sun,  moon,  or  stars. 

Sconce,  in  manufactures,  a  ]>ensile 
candlestick,  generally  with  a  mirror 
to  reflect  the  light 

Scotia,  the  hollow  moulding  in  the 
base  of  an  Ionic  column,  derived 
from  the  Greek,  signifying  shade, 
because,  from  being  hoUow,  part  of 
it  is  always  in  shadow.  The  scotia 
is  likewise  a  groove  or  channel  cut 
in  the  projecting  angle  of  the  Doric 
corona. 

Scovanlode,  a  lode  having  no  gozzan 
on  its  back  or  near  the  surface 

Scraper,  a  piece  of  iron  used  to  take 
out  the  pulverized  matter  which 
remains  in  a  hole  when  bored  pre- 
vious to  blasting 

Screen,  a  moveable  frame-work  to 
keep  off  an  excess  of  light,  or  heat, 
or  cold ;  a  separation ;  a  partition. 
In    ecclesiastical   architecture,    a 
screen  denotes  a  partition  of  stone, 
wood,  or  metal ;  usually  so  placed 
in  a  church  as  to  shut  out  an  aisle 
from  the  choir,  a  private   chapel 
from  the  transept,  the  nave  from 
the  choir,  the  high  altar  from  the 
east    end    of  the    building,    &c. 
Some  very  beautiful  examples  exist  j 
of  screens,  especially  of  those  se- 
parating the  choir  fh)m  the  nave. 
That  of  York  is  of  a  magnificent 
character.    '  All   Saints'  Church, 
Maidstone,'  a  work  published  in 
4to,  is  of  an  interesting  description 
on  this  head.    In  modem  architec- 
ture, a  single  open  colonnade,  ad- 
mitting a  view  through  it,  is  called 
a  screen  of  columns :  such  v^as  that 
formerly  in  front  of  Carlton  House. 


sen 


SCREW. 


SCR 


Grosvenor  House  has  a  Doric 
screen  in  front  of  it 
Screen  bulk-head,  in  ship -building, 
that  which  is  under  the  roundhouse 
Screw,  a  spiral  groove  or  thread 
vrinding  round  a  cylinder  so  as  to 
cut  all  the  lines  drawn  on  its  sur- 
face parallel  to  its  axis  at  the  same 
angle.  The  spiral  may  be  either 
on  the  convex  or  concave  surface 
of  the  cylinder,  and  it  is  called 
accordingly  either  the  screw  or 
the  nut.  The  screw  can  hardly  be 
called  a  simple  machine,  because 
it  is  never  used  without  a  lever  or 
.  -winch  to  move  it  home,  and  then 
it  becomes  an  engine  of  amazing 
power  and  utility  in  pressing  to- 
gether substances  that  have  little 
cohesion,  or  in  raising  to  short 
heights  ponderous  bodies.  The 
smith,  the  carpenter,  the  printer, 
and  the  packer,  all  use  screws  in 
their  respective  occupations.  Bales 
of  wool,  cotton,  hay,  &c.,  may  be 
compressed  by  means  of  a  screw 
into  packages,  the  specific  gravity 
of  which  shall  be  much  heavier 
than  an  equal  volume  of  water. 
Such  packages  will  then  sink  in 
the  ocean  like  a  cannon-shot. 
Moreover,  many  of  our  domestic 
operations  are  performed  by  means 
of  presses  or  screws ;  as  the  mak- 
ing of  sugar,  oil,  and  wine.  The 
screw  possesses  one  great  advan- 
tage over  the  inclined  plane,  from 
which  its  principal  of  action  may 
be  said  to  be  derived.  The  great 
attrition  or  friction  which  takes 
place  in  the  screw  is  useful 
by  retaining  it  in  any  state  to 
which  it  has  once  been  brought, 
and  continuing  the  effect  after  the 
power  is  removed.  It  is  thus  the 
cabinet-maker's  cramp,  the  smith's 
vice,  and  all  those  instruments 
made  by  mathematical  instrument, 
makers  in  which  screws  act,  can 
be  employed  with  certainty.  Screws 
are  made  with  threads  of  various 
forms :  some  have  sharp,  others 
square  or  round  threads. 
Screw-jack,  a  strong  screw  for  lifting 

391 


or  supporting  a  heavy  weight :  it 
rests,  by  means  of  a  large  nut, 
upon  a  hollow  base  or  pedestal, 
and  is  raised  or  lowered  by  turning 
the  nut. 
Screw.  Screw  propellers,  for  naviga- 
tion, by  means  of  steam  power,  have 
now  become  objects  of  importance 
to  all  nations,  more  particularly  for 
those  who  navigate  thebroad  waters : 
they  are  especially  applicable  for 
vessels  of  war,  the  machinery  for 
propulsion  being  without  the  reach 
of  shot.  Screw  propellers,  however 
variously  they  may  be  modified,  all 
derive  their  power  of  propelling 
by  being  placed  on  an  axis  which 
is  parallel  to  the  keel,  and  by  hav- 
ing threads  or  blades  extending 
from  the  axis,  which  form  seg- 
ments of  a  helix  or  spiral,  so  that, 
by  causing  the  axis  to  revolve,  the 
threads  worm  their  way  through 
the  water,  much  in  the  same  way 
as  a  carpenter's  screw  inserts  itself 
into  a  piece  of  wood.  There  is, 
however,  considerable  difference 
between  the  action  of  a  carpenter's 
screw  and  of  the  screw  propeller : 
the  latter,  acting  upon  a  fluid,  can- 
not propel  the  vessel  without  caus- 
ing the  water  to  recede,  while  the 
carpenter's  screw  progresses  thro' 
the  wood  without  any  such  reces- 
sion. The  law  which  governs  the 
distance  which  the  water  recedes 
is  common  to  the  paddle-wheel, 
and  to  all  bodies  moving  in  the 
water.  The  screw  propelling  is 
not  of  recent  construction ;  we  find 
that  so  early  as  1727,  Mr.  Duquet 
invented  an  hydraulic  screw  ma- 
chine, which  he  placed  between 
two  boats,  connected  by  transverse 
bearing,  to  which  the  screw  was 
afiixed.  Mr.  Paucton,  in  1768, 
published  his  •  Theory  of  the  Screw 
of  Archimedes;'  other  inventions 
followed,  until  a  recent  date,  when 
Mr.  George  Rennie  applied  his 
comprehensive  mind  to  the  sub- 
ject. Sir  John  Rennie  and  Mr. 
George  Rennie  undertook,  when 
all  other  engineers  declined  the 


SCREW  PROPELLER. 


SCR 


order,  to  coDBtract  the  eng;ine8  for 
the  Ship  Prapeller  Company  formed 
iu  1836,  to  _woik  out  Mr.  J.  P. 
Smith's  pat«nt  for  the  application 
of  the  screw  to  propel  «team  seuela, 
b;  placing  it  iu  a  space  to  be  left 
for  that  purpose,  in  that  part  called 
the  '  dead-wood ;'  that  ia,  the  solid 
wood-work  belweeo  the  Etem-post 


and  the  keel  of  the  vessel.     This 

screw  propeller  vessel  was  at  length 
launched,  and  the  engines,  by  the 
Messrs.  Rennie,  constructed.  This  ' 
vessel,  named  the  '  Archimedes,' ' 
was  considered  the  model  vessel,  | 
and  in  the  first  instance  fitted  with  < 
a  single-threaded  screw,  aa  shown  i 
in  the  accompanying  ditigram.         I 


Other  patents  were  subsequently 
takeD  out,  and  many  eiperiments 
made.  In  1B3B,  Mr.  Eiiccton  ob- 
tained a  patent  for  a  propeller  eon- 


let  at  equal  distances  round  a  cy- 1 
lioder  concentric  with  the  axis  i :  i 
the  blades  and  aims  were  segments 


SCREW  PROPELLER. 


SCR 


ofaicrew.  The Archimcdeui mtcv 
it  •  helix,  coniiiting  of  an  inclined 
plane  noond  round  a,  crlindei. 
Whra  auch  a  Krew  hia  commu- 
nicated s  retrograde  motion  to  the 
water  equal  to  its  own  recession , 
the  further  continuaDce  of  the 
thread  will  not  oal;  be  useleis, 
but  will  occasion  a  friction  by  its 


unuecetury  lur&ce.  Mr.  Bennie 
proposed  to  nmke  the  screw  ipiral 
initead  of  helical;  the  thread  of 
his  propeller  would  thus  be  gene- 
rated bywinding  an  inclined  plane 
round  a  logarithmic  cone  or  elaie. 
The  accompanying  diagrini  yrjSV. 
probably  best  expl^n  fte  method! 
adopted. 


Varioiu  other  methods  have  lince 
been  Boggested  and  adopted;  one 
by  Mr.  Blailand.  Thi»  propeller 
shaft  rests  upon  a  bearing  in  the 
&lse  stern-post,  which  is  fitted 
vrith  a  stuffing-box.  There  is  ai 
open  space  on  the  dead-wood,  ii. 
which  the  propeller  works,  similar 
to  that  of  the  'Archimedes,'  but 
the  propeller  rests  entirely  d_ 
the  bearing,  instead  of  having  an 
after-bearing  Uke  the  screw  of  that 
vessel.  Captain  Carpenter's  in- 
ventioD  was   adopted  by  the  Ad. 

393 


miralty  in  the  pinnace  'Geyser,' 
commanded  by  himself.  'There 
are  in  this  case  two  propellers, 
which  are  placed  in  the  quarters. 
They  receive  motion  by  means  of 
a  rotatory  engine,  called,  the  disc 
engine.  The  propellers  difFer  from 
all  others,  consisting  merely  of ' 
flat  trapezinms  attached  by  a 
to  the  axil !  they  are  therefore  not 
portions  of  a  screw,  though  this 
action  is  helical.  In  May,  1843, 
Mr.  Beonet  Woodcraft  was  directed 
by  the  Lords  of  the  Admiralty  tc 


SCREW  PROPELLER. 


mike  a  screw  at  hia 

own  coit. which  they 
caiued  to  be  tried  in 
the  •  lUttler.'  Thii 
■crew  iras  made  of 
copper,  hiring  four 
bladea ;  and  it  carre- 
iponded  in  every  re- 
spect with  a  screw 
of  an  uniform  pilch, 
alio  made  of  copper, 
in  the  number  of  its 
bUdea,  its  diBmet«r, 
lea  ph  andpitch,witfa 
this  exception,  that 
although  the;  each 
commenced  with  the 
same  pitch,  yet  Mr. 
Woodcroft'a  screw 
gradually  increased 
in  its  pilch  through- 
tmd  l«nDi]i[iMd 


e  of 


Afler  this 


a  per  cent,  additional 

pitch.    The  trial  of 

Smith's   four-bladed 

Archimedean  or  true 

screw  took  place  in 

the  '  Rattler,'  on  the 

18th  of  March.  1844; 

and  on  the  13lh  of 

the  following  month , 

a    trial    of   Wood- 

croft's      increasing- 
pitch  screw,  of  four 

Ejlades,  was  made 
with  the  same  vessel 
tiial,  Mr.  Llojd,  the  chief  engineer 
at  the  Admiralty,  who  had  been 
present  to  superintend  it,  stated  to 
Mr,  Wooden^,  who  had  also  been 
present,  that  the  latter  screw  was 
superior  to  tlie  uniform  pitch  screw 
in  two  important  qualities :  first, 
that  it  propelled  the  vessel  at  an 
equal  speed  with  leas  power ;  and, 
secondly,  that  it  also  propelled  the 
Yessel  at  an  equal  «peed  with  fewer 
revolutions  of  the  screw,  which 
latter  quality  he  considered  su- 
perior to  the  former ;  but  that  the 
difficulty  arising  from  having  to 
drive  screws  so  fatt,  constituted 
the  greatest  obstacle  to  their  in- 


troduction in  the  Royal  Navy.  In-  \ 
deed,  this  is  the  admitted  diffitmlty 
in  the  application  of  the  screw  as , 
a  marine  propeller,  and  the  prac- 
tical difference  between  it  aod  tbe 
paddle-whed.  The  great  aiie  of 
latter  enables  the  speed  of  the 
engines  to  accomplish  the  required 
velocity  of  the  boat,  whereas  the 
small  diameter  of  the  screw  renders 
it  necessary  thsl  it  should  perform 
many  more  revolutions  than  tbe 
engine  makes  strokes.  Hence  the 
necessity  of  introducing  some  mul- 
tiplying gearing  between  the  ei^ne 
and  the  propeller;  and  thii  mul- 
tiplying gear,  consisting  of  catt-iron 
cog-wheels  and  pinions,  it  neces- 


394 


SCR 


SCREW-CUTTmO  MACHINE. 


SCR 


sarily  liable  to  frequent  breakage 
and  damage.    The  great  object  to 
be  DOW  a(^eved  in  the  application* 
of  the  screw  as  a  marine  propeller, 
is  to  introduce   an  intermediate 
gearing  for  multiplying  the  yelodty, 
which  shall  not  be  liable  to  acci- 
dent, or  to  render  this  geuing 
altogether   unnecessary.     Smith's 
screw,  however,  with  some  mo- 
difications of  his  former  patent, 
now  diminished  to  two  blades,  is 
used  in  the  navy  to  some  extent. 
Screw -cutting  Machine.     The  ma- 
chinery  aihipted  to  this  purpose 
varies  in  construction  according  to 
the  notions  of  the  different  makers, 
but  the  general  principle  is  the 
same  in  all,  the  d^erence  consist- 
ing in  the  method  of  canTing  it  into 
effect.  The  machine  is  a  compound 
of  the  '  slide-rest  *  and  lathe,  with 
a  train  of  wheels  to  ^ve  motion  to 
the  former.    The  metal  to  be  cut 
into  a  screw  is  placed  between  the 
centres  of  the  lathe  in  the  usual 
manner,   and  the  cutting-tool  is 
fixed  upon  the  slide -rest,  which 
has  its  lower  slide  made  parallel 
to    the    centre   line;    the    upper 
slide  is  only  used  for  adjusting 
the  cutting-tool.     The  screw  of 
the  lower  sUde  has  motion  com- 
municated by  the  train  of  three  or 
more  wheels;  the  first,  or  driving 
wheel,  is  fixed  on  the  mandril  of 
the  lathe,  and  the  last  of  the  train 
is  fixed  on  the  end  of  the  slide- 
screw  ;  the  other  wheels  are  inter- 
mediate wheels.    The  pitch  of  the 
screw  to  be  cut,  or  distance  be- 
tween the   centres   of  two   con- 
secutive   threads,    is    the    space 
traversed  by  the  tool  during  one 
rev<^ution  of  the  work,  and  is  re- 
gulated by  the  sizes  of  the  wheels, 
which  must  therefore  be  changed 
for  every  difference  in  the  pitch. 

The  perfection  to  which  screw- 
cutting  has  been  brought,  is  mainly 
attributable  to  the  appUcation  of 
the  slide-rest;  and  the  beautiful 
and  accurate  screws,  of  all  sizes, 
produced  by  the  screw-cutting  ma- 

395 


chine,  have  contributed  in  no  small 
degree  to  the  perfection  of  our  ma- 
chinery in  general,  and  more  par- 
ticularly to  that  of  astronomical 
instruments. 

There  are  also  other  machines, 
called  screvring  machiQes,forscrew. 
cutting,  which  perform  work  of  5 
much  rougher  description,  such  a 
cutting  short  screws  on  bolts,  fo 
fastening  together  the  flanges   o 
pipes,  &c.     The  machine  consists 
of   a   strong   iron   frame,   which 
carries  a  mandril  somewhat  similar 
to  that  of  a  lathe,  driven  by  a  band 
passing  over  a  pulley.    The  head 
of  the  bolt  to  be  screwed  is  held 
by  a  damp  at  the  projecting  end 
of  the  mandril,  so  that  it  revolves 
with  it  as  in  a  lathe,  the  only  dif- 
ference being,  that  it  is  held  at 
one  end  and  free  at  the  other.  The 
dies,  or  two  hardened  steel  pieces, 
which  together  form  a  nut,  vrith 
the  grooves  lengthvrise  for  cutting, 
are  placed  in  a  small  frame,  across 
the  machine,  supported  by  two 
guides  projecting  from  the   ma- 
chine frame,  one  on  each  side, 
level  and  parallel  vrith  the  bolt. 

When  the  machine  is  set  in 
motion,  the  small  cross  frame  is 
brought  forward,  and  the  end  of 
the  revolving  bolt  is  made  to  enter 
the  dies,  which  are  pressed  upon  it 
by  set- screws;  and  as  their  cut- 
ting edges  take  effect  on  the  bolt, 
the  frame  is  carried  forward  on  the 
guides  till  it  has  moved  the  re- 
quired length;  it  is  then  brought 
back  by  reversing  the  motion  of 
the  machine,  and  the  dies  are 
tightened  for  another  cut:  this 
operation  is  repeated  until  the 
screw  is  of  the  required  diameter. 
By  fixing  a  tap,  or  cutting-sceew, 
to  the  mandril,  in  place  of  the  bolt, 
and  holding  a  nut  by  the  screws  in 
the  cross  frame,  the  machine  is 
made  to  cut  internal  screws. 

SeriMng^  a  term  applied  to  the  edge 
of  a  board  when  fitted  upon  any 
surface 

Seribmfff  in  joinery,  the  act  of  fitting 


scu 


SCULPTURE. 


SCU 


one  piece  of  wood  upon  another, 
so  that  the  fibres  of  both  may  be 
perpendicular  to  each  other,  and 
the  end  cut  away  across  the  fibres, 
so  as  to  fit  upon  the  side  of  the 
other 
Scrint  in  mining,  a  small  vein 
ScroUt  a  name  given  to  a  kind  of 
ornament  of  general  use,  which 
resembles  a  btmd  arranged  in  un- 
dulations or  convolutions 
Seu^ture  is  the  art  of  carving  wood 
or  hewing  stone  into  images.  It 
is  an  art  of  the  most  remote  anti- 
quity,  having  been  practised,  there  is 
reasonto  suppose,  before  the  Deluge.  * 
To  this  reason  is  assigned  the  ex- 
pedients by  which,  in  the  first  stages 
of  society,  the  images  of  men  have 
every  where  supplied  the  place  of 
alphabetical  characters.  These,  it 
is  universally  known,  have  been 
picture  writing,  such  as  that  of  the 
Mexicans,  which,  in  the  progress 
of  refinement  and  knowledge,  were 
gradually  improved  into  the  hiero- 
glyphics of  the  Egyptians  and  other 
ancient  nations.  To  make  a  dis- 
tinction between  carving  and  sculp- 
ture, the  former  belonged  exclu- 
sively to  wood  and  the  latter  to 
stone.  The  latter  evinced  vast 
comprehension  of  mental  taste  and 
study  of  human  anatomy  as  well  as 
that  of  other  animals.  In  examin- 
ing the  various  sculptures  of  the 
Egyptians,  it  is  found  that  a  gene- 
ral character  prevails  throughout 
their  outlines :  many  valuable  spe- 
cimens remain  to  attest  their 
greatness  in  this  art.  It  is  to  the 
Greeks  that  great  superiority  is  due. 
The  art  of  sculpture  probably  was 
influenced  by  the  climate  over  the 
human  frame,  as  the  violent  heats 
of  the  torrid  zone  and  the  excessive 
cold  of  the  polar  regions  are  un- 
favourable to  beauty :  it  is  only  to 
the  mild  climates  of  the  temperate 
regions  that  it  appears  in  its  most 
attractive  charms.  The  Romans  dis- 
played great  talents  for  statuary; 
subsequently  the  Italian  masters 
showed  their  eminence  in  the  art ; 

396 


and  in  our  own  country  the  works 
of  Westmacott  and  Chantrey  be- 
long to  the  distinguished  English 
School.  Carving  in  wood  exists  in 
the  fine  and  most  elaborate  works 
of  Flemish  masters,  and  those  of 
Gibbons  and  others  of  England  sre 
of  equal  talent  in  this  plesAog 
art. 

The  Grecian  marbles  in  the 
British  Museum  have  given  so  much 
grace  to  British  art,  and  to  execu- 
tion in  the  art  generally,  that  a 
short  description  of  them,  and  their 
connection  with  architecture,  ?ill 
not  be  unacceptable. 

We  learn  from  Athenian  Stuart, 
that  <'the  Temple  of  Minena, 
called  the  Parthenon  and  Heca- 
tompedon,  was  buUt  during  the 
administration  of  Pericles,  who  em- 
ployed Callicrates  and  Ictinua  as 
architects,  under  Phidias,  to  whom 
he  committed  the  direction  of  all 
works  of  elegance  and  magnificence. 
It  has  been  celebrated  by  some  of 
the  most  eminent  writers  of  au- 
tiquity,  whose  accounts  are  con- 
finned  and  illustrated  in  the  de- 
scriptions given  us  by  those  tra- 
vellers who  saw  it  almost  entire  in 
the  last  century.  Even  in  its  present 
state,  the  spectator  on  approaching 
it  will  find  himself  not  a  little  af- 
fected by  so  solemn  an  appearance 
of  ruined  grandeur.  Accustomed 
as  we  were  to  the  ancient  and 
modem  magnificence  of  Rome,  and 
by  what  we  had  heard  and  read, 
impressed  with  an  advantageous 
opinion  of  what  we  were  come  to 
see,  we  found  the  image  our  fancy 
had  preconceived  greatly  inferior 
to  the  real  object. 

"  This  temple,  the  most  costlyand 
highly  finished  example  of  the  Done 
Older,  perhaps  the  largest  octastyle 
temple  of  antiquity,  had  the  ad- 
vantage of  the  greatmindof  FhidiaS' 
It  is  to  Lord  Elgin's  enterprise  and 
enthusiasm  for  art  that  England 
owes  the  unique  treasures  deposited 
in  the  British  Museum.  F^^^' 
sanias  remarks,  *  On  entering  the 


sou 


SCULPTURE. 


SCU 


temple  called  the  Parthenon,  all 
the  works  in  what  are  termed  the 
pediments  (eagles)  seem  to  relate  to 
the  birth  of  Minerva ;  those  behind 
represent  the  contest  of  Neptune 
aad  Minerva  concerning  Attica;  but 
the  statue  itself  (of  the  goddess)  is 
formed  of  ivory  and  gold/  Pausa- 
nias  then  proceeds  to  a  minute  de- 
scription of  the  chryso-elephantine 
statue,  notices  other  monuments  of 
art,  describes  the  Erechtheum,  and 
enlarges  on  the  colossal  bronze  Mi- 
nerva by  Phidias,  called  Promachus, 
&c  The  beauty  of  the  marble  of 
the  mountains  surrounding  Athens, 
particularly  that  of  Pentelicus,from 
which  the  temple  Parthenon  was 
wrought,  must  have  given  a  great 
zest  to  the  Athenians  in  the  culti- 
vation of  the  refinement  of  archi- 
tectural design;  with  more  bril- 
liancy, it  is  almost  capable  of 
receiving  the  high  finish  of  ivory. 
According  to  Pliny,  Diopoenus  and 
Scyllis,  bom  in  Crete  about  the 
50th  Olympiad,  b.c.  578,  were  the 
first  sculptors  distinguishedin  work- 
ing marble,  and  to  them  are  also 
attributed  the  earliest  statues  of 
ivory  and  gold.  Of  the  part 
Phidias  had  in  the  design  of  the 
Parthenon  temple,  and  in  the  pro- 
duction of  the  sculpture  in  parti- 
cular, a  diversity  of  opinion  has 
existed.  It  has  been  supposed  that 
the  whole  of  the  sculptural  deco- 
rations are  the  'undoubted'  pro- 
ductions of  that  great  artist,  thus 
conveying  to  them  a  charm,  from 
the  association  of  that  great  name, 
which  the  unequal  execution  does 
not  entitle  portions  of  them  to  re- 
ceive: others  assert  that  he  had 
nothing  to  do  with  the  works,  but 
that  he  may  have  designed  the 
sculpture.  However,  the  words '  skU- 
fid  sculptor  in  marble'  have  been 
applied  by  Aristotle  to  Phidias,  in 
opposition  to  '  statuary,'  given  by 
him  to  Polycletus,  whose  works 
were  principally  in  bronze,  in  order 
to  strengthen  the  probability  of  his 
having  executed  the  marble  sculp- 

397 


tnre  of  the  Parthenon.  Pliny  states 
Phidias  to  have  been  the  first  who 
displayed  and  perfected  the  toreutic 
art,  or  sculpture  formed  by  the 
combination  of  metals  and  other 
materials.    The  fertility  of  genius 
of  this  great  sculptor,  who  was 
equally  skilful  in  every  department 
of  his  art,  was  surprising.  He  was, 
at  the  period  of  the  erection  of  the 
Parthenon,  engaged  in  so  many  and 
such  various  monuments  belonging 
to  the  toreutic  art,  that  his  atten- 
tion must  have  been  occupied  by 
them  to  so  great  a  degree,  that  any 
but  a  general  superintendence  of 
the   designs   of  the   temple   can 
scarcely  be  supposedpossible.  When 
executing  the  Minerva  of  the  Par- 
thenon, he  had  already  completed 
or  was  engaged  on,  besides  many 
other  statues  and  groups  in  ivory 
and  gold,  five  other  statues  of  that 
goddess,  probably  all  of  them  co- 
lossal, of  which  the  Minerva  Pro- 
machus, in  bronze,  in  the  acropolis, 
must  have  been  upwards  of  50  feet 
in  height,  having  been  seen  ^m 
the  sea.    The  passage  of  Plutarch, 
describing  the  artists  of  the  struc- 
tures of  Pericles  is,   'Phidias  di- 
rected and  superintended  all  the 
works  for  him  (Pericles),  although 
they  had  great  architects  and  arti- 
ficers; for  Callicrates  and  Ictinus 
executed  the   Hecatompedon,   or 
Parthenon.' " 
Sculpture,   Mr.  Hailes,  in  1 825,  writes 
the  following: — "The  introduc- 
tion of  statues  of  individuals,  how- 
ever eminent  and  meritorious,  into 
squares    and  public  places,,  is  a  i 
novelty  in    this    our   metropolis,  • 
which,  till  of  late  years,  seemed  I 
to  be  reserved  for  the  sovereign 
and  his  family.    We  have,  how-  ; 
ever,  two,    which,  although  not  i 
contrary  to  law,  at  least  to  any 
that  I  know  of,  are  certainly  de- 
viations from  long  established  cus- 
tom, and  a  sort  of  invasion  or 
trespass   upon    royal  prerogative. 
That  of  the  late  Duke  of  Bedford, 
the  Triptolemus  of  his  time,  in 


8 


scu 


SEAL. 


SEA 


Russell  Square,  is  an  erect  figure, 
surrounded  by  the  attributes  of 
husbandry;  and  beneath  it  are  some 
smaller  figures,  equally  symbolic. 

The  late  Bishop  of  E ,  going 

with  a  friend  to  look  at  this  statue, 
was  asked  by  him  what  he  thought 
would  be  the  fittest  inscription  for 
it.  His  answer  was,  *  Bovi.  Opti- 
mo. Maximo.'  It  seems  extra- 
ordinary that  his  Grace,  with  these 
emblems  of  agriculture  about  him, 
has  not  been  made  to  look  towards 
the  country  instead  of  the  town. 
But  he  looks  towards  Mr.  Fox,  the 
Demosthenes  of  our  day,  in  Bed- 
ford Square,  sitting  in  a  lumpish 
manner  in  a  sort  of  curule  chair,  and 
hal^ited  in  a  toga,  a  la  Rmnames — 
his  neck  is  exposed,and  the  drapery, 
passing  over  one  of  his  shoulders 
across  his  breast,  might  very  well 
give  occasion,  as  it  did,  to  one  of 
his  old  Westminster  constituents, 
to  say,  '  So,  Charley,  you  are  going 
to  be  shaved,  I  see.'  These  are 
two  very  sharp  remarks :  one  from 
a  very  highly  cultivated  man,  and 
a  great  scholar ;  and  the  other  from 
a  very  coarse  observer,  but  equally 
shrewd  and  comical  in  their  way. 
They  seem  to  supersede  the  neces- 
sity of  any  other  criterion.  We 
are  not  happy  in  this  branch  of 
the  fine  arts ;  and  the  only  instance 
in  which  we  can  pride  ourselves  is 
not  of  a  late  date,  being  the  eques- 
trian statue  of  Charles  the  First, 
by  a  scholar  of  John  de  Bologna, 
at  Charing  Cross.  Our  ill  success 
is  perhaps  the  less  to  be  lamented, 
as  works  of  this  sort,  exposed  to 
such  an  atmosphere  as  we  live  in, 
become  in  a  short  time  so  much 
defaced  as  to  make  it  veryindiffer- 
ent  whether  the  workmanship  be 
from  the  hand  of  a  Glycon  or  a 
Bacon.  All  our  monuments  of 
this  kind  seem  to  represent  our 
chimney-sweepers,  a-foot  or  on 
horseback,  rather  than  our  kings, 
princes,  and  other  great  men." 
The  kte  Mr.  Nash  observed,  "  that 
these  criticisms  are  unjust  as  well 

398 


as  impolitic :  by  running  down  the 
best,  we  open  the  door  to  the  worst 
artists.  It  is  a  peculiarly  English 
feeling.  If  Westmacotf  s  hronzes, 
which  one  hardly  dares  (in  the 
face  of  critidsm)  to  pronounce 
unrivalied  in  this  country,  had  re- 
ceived their  due  praise,  the  de- 
signer of  the  Duke  of  Kent,  at  the 
top  of  Portland  Place,  would  never 
have  been  suffered  to  libel  the  state 
of  English  art." 

Scumblmg  is  giving  a  kind  of  rough 
dotted  shadow  to  trees,  gra8s,graveU 
walks,  &c.,  in  a  drawing  when  it  is 
nearly  finished.  It  is  performed 
with  a  brush  having  some  dark 
brown  colour  in  it,  but  nearly  dry. 
The  hairs  of  the  brush  are  spread 
apart,  then  held  in  a  slanting  direc- 
tion, and  swept  lightly  over  the 
foreground,  or  where  the  shadows 
are  wanting.  This  is  practised  by 
some  artists  with  considerable  ef- 
fect. 

Scuppers,  holes  cut  through  a  ship's 
side  for  throwing  off  the  water  from 
the  pump.  They  should  be  dis- 
posed clear  of  the  guns,  standards, 
the  ports  below,  gangways,  &c. 

SctUcheon,  the  shield  represented  in 
heraldry 

SctUilet,  holes  cut  in  divers  parts  of 
the  decks,  exclusive  of  hatchways 
and  ladderways;  likewise  holes  cut 
through  the  ship's  side  for  air 

Scyricum  Marmora  a  name  given  by 
the  ancients  sometimes  to  a  white, 
and  sometimes  to  a  yellowish  mar- 
ble ;  both  used  in  the  public  build- 
ings  of  the  Romans,  but  seldom  in 
statuary,  not  being  capable  of  re-  { 
ceiving  a  high  polish 

Sealt  a  device  or  an  engraved  inscrip- 
tion :  also  its  impression  made  on 
wax.  Kings,  bishops,  and  prelates 
were  accustomed  to  use  their  several 
devised  seals.  Cities,  towns,  cor- 
porations, companies,  institutions, 
and  public  bodies,  had  their  seals. 
Privy/ or  individual  seals  were  also 
oi  frequent  use,  and  some  very 
curious  seals  exhibit  much  beauty 
and  ingenuity.     That  represented 


Scam,  in  mioiDg,  a  hoTBe-load 

~  nnu,  the  opeaing  between  the  planks 
when  wrought 

Stemni,  a  true  line  that  cuti  aaother 
or  divides  it  into  two  puts 

Seelim,  s  verticai  pUn  of  the  ioterior 
of  a  building,  showing  it  u  it  would 
appear  upon  an  upiight  plane  cut- 
ting through  it.  Though  raretj 
thown,  lectioni  are  almost  as  in- 
diipenssble  ai  plana ;  Uke  which 
the}'  ihow  the  thicVnesses  of  the 
waUs,  and.  in  addiUon,  those  of 
the  ceilings  and  floors ;  and  also 
heights,  both  of  the  rooms  them- 
lelies,  and  of  doors  and  windows ; 
— moreover,  the  forms  of  the  ceil- 
ings, whether  flat,  or  coved,  or 
vaulted.  In  one  leipect,  too,  a 
•ection  partakes  of  the  nature  of  an 
elevation,  the  pUoe  parallel  to  the 

399 


hoe  of  lection  being  aii  elevatioi 
the  interior,  or  rather  consisting  of 
as  many  elevations  as  there  are  se- 
parate rooms  or  divisions.  Sections 
may  be  described  as  either  furnished 
or  unfurnished ;  the  latter  shon 
only  construction  and  the  strictly 
architectural  parts;  wherefore,  if 
the  side  of  a  room  happens  to  be 
quite  plun,  without  door,  cliimney- 
piece,  or  other  feature,  that  side  or 
spsce  will  be  a  blank,  or  little  better. 
Furiiisherl  sections,  on  the  contrary, 
exhibit,  besides  wbal  stricti;  be- 
longs to  the  architecture  and  its 
decoration,  mirrors,  pictures,  sta- 
tues, furniture,  draperies,  and  all 
other  accessories.  The  number  of 
sections  required  depends  upon  the 
nature  of  the  plan,  and  n-liat  may 
be  worth  showing.    Iflhedeais    ' 


SEC 


SEPULCHRE. 


SEP 


woiihy  of  it,  there  should  be  as 
many  Bections  as  'will  suffice  to 
show  every  side  of  every  principal 
apartment ;  though  it  may  not  be 
necessary  to  repeat  the  entire  sec- 
tion through  every  floor.  Sections 
are  the  delicia  of  architectural 
illustration. 

Sector  J  in  geometry,  an  instrument  of 
wood  or  metal,  with  a  joint  and 
sometimes  a  piece  to  turn  out  and 
make  a  true  square,  with  lines  of 
sines,  tangents,  secants,  equal  parts, 
rhombs,  polygons,  hours,  latitudes, 
&c. 

Sedilkij  a  name  for  a  seat :  the  term 
is  applied  to  the  seats  for  the  offi- 
ciating priests,  inserted  (  and  some 
ornamented)  in  the  south  wall  of 
a  church 

Segment  of  a  circle,  a  part  of  a  circle 
bounded  by  an  arc  and  its  chord, 
and  either  greater  or  less  than  a 
semicircle 

Segment  qf  a  sphere,  any  part  of  a 
sphere  cut  off  by  a  plane,  the  sec- 
tion of  which,  with  the  sphere,  is 
always  a  circle 

Selia,  (Latin,)  the  general  term  for  a 
seat  or  a  chair  of  any  description. 
Sella  CurulU,  a  chair  of  state. 

Semaphore,  in  mechanics,  a  name 
given  by  the  French  tothe  telegraph, 
and  latterly  adopted  in  England  to 
signify  any  machine  to  communi- 
cate intelligence  by  signs  or  sig- 
nals 

Semicircle,  half  a  circle,  or  the  area 
comprehended  between  a  diameter 
and  the  semi-circumference 

Semi'Ordinate,  in  conic  sections,  a 
line  drawn  at  right  angles  to  and 
bisected  by  the  axis,  and  reaching 
from  one  side  of  the  section  to  the 
other 

Sepia,  Seppia,  or  ^thiopt^mineraL 
This  pigment  is  named  after  the 
sepia  or  cuttle,  which  is  called  also 
the  ink-fish,  from  its  affording  a 
dark  liquid  which  was  used  as  an 
ink  and  pigment  by  the  ancients. 
From  this  Uquid  our  pigment  sepia, 
which  is  brought  principally  from 
the  Adriatic,  may  be  obtained  from 


the  fish  on  our  own  coasts ;  and 
it  is  supposed  that  it  enters  into 
the  composition  of  the  Indian 
ink  of  the  Chinese.  Sepia  is  of  a 
powerful,  dusky  brown  colour,  of  a 
fine  texture :  it  works  admirably  in 
water,  combines  cordially  in  other 
pigments,  and  is  very  permanent. 
It  is  much  used  as  a  water-colour, 
and  in  making  drawings  in  the 
manner  of  bistre  and  Indian  ink, 
but  it  is  not  used  in  oil,  in  'which  it 
dries  very  reluctantly. 

Septuagint,  the  Greek  version  of  the 
books  of  the  Old  Testament^  so 
called  because  the  translation  is 
supposed  to  have  been  efiTected  by 
seventy-two  Jews,  who  are  nsaally 
called  the  seventy  interpreters 

Septdchre,  a  grave,  tomb,  or  place  of 
interment.     Extreme  attention  to 
the  sepulture  of  deceased  friends 
characterized  nations  frxim  remote 
antiquity,  and  to  be   deprired  of 
it  was  accounted  a  very  degrading 
circumstance.     The  Romans  were 
prohibited  by  a  law  from  burying 
their  dead  within  the  city  ;  and  it 
was  a  field  that  the  father  of  the 
Jews  purchased  for  the  sepulture 
of  his  wife.    "  Hear  us,  my  lord : 
in  the  choice  of  our    sepulchres 
bury  thy  dead;  none  of  us  shall 
'withhold  from  thee  his  sepulchre, 
but   that  thou  mayest  bury,  thy 
dead.'' — Gen.  xxiii.  6.   The  ancient 
tombs  of  the  East  are  remarkable 
for  their  durability,  and,  in  some 
instances,  their  beauty:    they  are 
monuments  on  which  the  lapse  of 
ages  effects  no  change;  in  many 
instances  hewn  in  the  solid  rock, 
they  are  calculated  for  duration 
equal  to  that  of  the  hills  in  which 
they  have  been  excavated.    In  a 
garden,  hewn  out  of  a  rock,  was 
the  sepulchre  of  Jesos. 

As  an  instance  of  a  style  of  modern 
sepulture,  which  is  rapidly  extend- 
ing, may  be  mentioned  the  Ceme- 
tery of  Pere  la  Chaise,  at  Paris, 
which  comprehends  above  150 
acres,  thickly  studded  with  cb^iels, 
tombs,  and  monuments,  beratified  j 


400 


SER 


SEWERS. 


SEW 


^th  winding  walks,  curtained  with 
lofty  shady  trees,  and  adorned  with 
plants  and  evergreens.  It  contains 
nearly  16,000  mausolea  built  of 
the  finest  granite,  sandstone,  and 
polished  Carrara  marble,  the  ex- 
pense  of  which  has  been  estimated 
at  about  120,000,000  francs,  or 
£  5,000,000  sterling. 

Serges,  the  great  wax  candles  burnt 
before  the  altars  in  Roman  Catholic 
churches 

Serpentine,  the  ophites,  or  serpent- 
stone  of  the  ancients.  Mona  mar- 
ble is  an  example  of  serpentine, 
and  the  Lizard  Point,  Cornwall,  is 
a  mass  of  it. 

Serving,  in  navigation,  encircling  a 
rope  with  line  or  spun-yam,  to 
prevent  its  being  chafed 

Set-off,  or  Offset,  the  part  of  a  wall, 
&c.,  which  is  Exposed  horizontally 
when  the  portion  above  it  is  reduced 
in  thickness 

Seterey,  a  bay  or  compartment  of  a 
vaulted  ceiling 

Sewers  are  subterranean  passages  or 
channels  for  the  conveyance  of 
waste  waters  and  other  matters 
from  towns  and  buildings.  In 
order  that  a  sewer  shall  act  with 
efficiency  and  promote  the  rapid 
discharge  of  the  matters  committed 
to  it,  it  is  necessary  that  it  be  con- 
structed thoroughly  impermeable 
throughout  its  entire  length,  that 
its  interior  surface  be  even  and 
smooth,  and  present  no  impedi- 
ments  to  the  sewage,  and  that  its 
vertical  dechnation  be  sufficient  to 
prevent  any  suspension  of  the  cur- 
rent. The  sectional  area  of  the 
sewer  should  be  amply  sufficient  to 
contain  the  entire  volume  of  the 
sewage,  and  its  form  such  as  will 
best  secure  its  action  with  the 
minimum  contents.  The  form  of 
a  sewer  should  be  adapted  to  resist 
the  utmost  pressure  to  which  it 
may  be  exposed  externally  from 
the  surrounding  materials  in  which 
it  is  constructed ;  and  ready  access 
should  be  afforded  at  intervals  for 
examining  its  condition  from  time 

401 


to  time,  and  detecting  and  removing 
any  obstruction  which  may  possibly 
occur  to  the  immediate  passage  of 
the  sewage.  Hence  rectangular 
forms  are  utterly  inapplicable  for 
these  works,  the  section  of  which 
should  be  entirely  curvilinear;  and 
theory  and  experience  have  con- 
curred in  appointing  a  sectional 
form,  similar  to  that  of  the  egg,  as 
best  fulfilling  the  conditions  of 
strength  to  resist  external  pressure, 
and  (the  smaller  curve  being  placed 
downwards)  to  produce  the  most 
activity  in  the  current  when  the 
quantity  of  sewage  is  reduced  to 
the  minimum.  The  simplest  and 
best  rule  for  obtaining  with  circular 
curves  a  true  egg-shaped  or  oviform 
section  for  sewers  is  that  given  in 
the  *  Rudimentary  Treatise  on  the 
Drainage  and  Sewage  of  Towns 
and  Buildings,'  belonging  to  the 
same  series  with  this  work,  and 
which  is  therefore  here  quoted. 

<«Let  the  greater  diameter,  or 
that  of  the  upper  part  of  the 
section,  equal  1 ;  the  less  diame- 
ter, or  that  of  the  bed  of  the 
sewer,  equal  *5;  and  the  entire 
height  of  the  section  equal  the  sum 
of  these,  or  1*5.  Then  strike  a 
semicircle  of  1  diameter  for  the 
head  or  arch  of  the  section,  and 
120°  of  a  circle  of  *5  diameter  for 
the  invert;  connect  the  arch  and 
invert  with  side  arcs  of  1*5  radius, 
the  centres  of  these  side  arcs  being 
on  the  produced  horizontal  diame- 
ter of  the  top  arch.  These  arcs 
will  be  truly  tangential,  both  to  the 
arch  and  invert,  and  will  complete 
a  section  well  adapted  for  the  prac- 
tical purposes  of  the  sewer,  and, 
being  so  extremely  simple  in  its 
construction,  peculiarly  ready  of 
application  by  workmen  in  forming 
and  using  templates,  and  in  testing 
the  accuracy  of  the  work  as  it  pro- 
ceeds. The  proper  size  or  sectional 
area  of  sewers  is  determinable  upon' 
the  quantity  of  sewage,  and  the 
velocity  of  its  passage,  which  Utter 
element  depends  jointly  upon  the 


SEW 


SEWERS. 


SBW 


rate  of  declivity  at  which  the  sewer 
is  laid,  and  the  volnme  of  water  in 
motion.  The  quantity  of  sewage 
to  be  conveyed  from  a  town  is  made 
up  chiefly  of  the  bulk  of  the  water 
supplied  to  the  population,  the  ex- 
crementitious  matters  produced, 
and  the  quantity  of  rain-water  falling 
upon  the  surface.  The  maximum 
quantity  thus  accruing  during  any 
given  period  of  time  will  determine 
the  minimum  capacity  of  the  sewer, 
calculated  in  combination  with  the 
rate  at  which  the  passage  can  be 
effected ;  while,  on  the  other  hand, 
the  minimum  quantity  thus  accru- 
ing will  limit  the  proper  radius  of 
the  invert  of  the  sewer,  so  that  the 
friction  of  the  water  against  the 
surface  of  the  sewer  may  be  re- 
duced in  proportion  to  the  total 
bulk  of  the  sewage.  All  junctions 
of  one  line  of  sewer  with  another, 
and  all  changes  of  direction  what- 
ever, should  be  formed  with  curves 
of  the  greatest  possible  radius,  ex- 
periment having  proved  that  the 
current  is  impeded  in  proportion 
as  the  radius  of  curvature  is  reduced, 
and  that  angular  junctions  are  still 
more  mischievous  in  suspending  the 
proper  action  of  the  channel.  Thus 
in  a  sewer  2  feet  6  inches  wide,  a 
stream  having  a  velocity  of  250  feet 
per  minute  suffers  a  resistance  from 
a  rectangular  change  of  direction 
three  times  that  produced  with  a 
curve  of  20  feet  in  radios,  and 
double  that  produced  with  a  curve 
of  5  feet  radius.  The  inevitable 
effect  of  suspending  the  -motion  at 
these  junctions  is  that  the  solid 
particles  become  deposited,  and 
form  a  permanent  bar,  requiring 
some  extraordinary  action  or  force 
of  water  to  remove  it. 

'*  It  is  usual  to  distinguish  sewers 
according  to  their  size  and  func- 
tions, as  first  class,  or  main  sewers; 
second  class,  or  collateral  sewers ; 
and  third  class,  or  branch  sewers ; 
while  the  smaller  channels  for  con- 
veying the  contributions  from  indi- 
vidual tenements  are  termed  drains, 

402 


The  same  rules  will  apply  equally 
to  all  of  these  as  far  as  their  proper 
objects  are  concerned,  although  the 
peculiar  construction  to  be  adopted 
will  of  course  depend  to  some  ex- 
tent upon  the  actual  size  of  eicb 
channel.  For  the  larger  sewers, 
constructions  of  brick-work  ire 
commonly  used.  These  require 
careful  formation,  and  to  be  accu- 
rately jointed,  and  the  interior  of 
the  invert  at  any  rate  smootUy 
formed  vrith  a  hard-drying  cement. 
For  smaller  channels  or  drains  and 
branch  sewers,  whole  pipes  of  glazed 
stone-ware  are  cominginto  extended 
employment,  and,  if  truly  formed 
and  ciurefully  laid  and  jointed,  these 
form  very  superior  ducts  for  the 
passage  of  the  sewage.  By  the  use 
of  these  pipes,  the  essential  quali- 
fication of  impermeability  is  better 
secured  than  with  brick  sewers,  the 
repeated  joints  of  which  need  great 
labour  and  care  in  construction,  and 
if  formed  with  inferior  mortar,  soon 
become  imperfect.  As  necessary 
appliances  to  all  sewers  and  drains, 
efficient  traps  or  apparatus  to  pre- 
vent the  escape  of  the  noxious  ps^ 
engendered  within  the  channels  are 
really  indispensable,  and  these  are 
required  to  be  simple  in  construc- 
tion and  unerring  in  their  action. 
The  entire  subject  of  the  sewage 
of  towns  and  buildings  is  now  first 
receiving  the  attention  due  to  it  as . 
a  necessary  condition  to  the  public 
health ;  and  when  this  important , 
branch  of  engineering  science  shall 
have  been  thoroughly  investigated 
by  qualified  public  officers,  we  may  | 
hope  for  the  most  useful  and  salt>* , 
tary  practice,  based  upon  correct: 
principles,  and  for  corresponding! 
amendment  in  all  that  pertains  to  | 
the  subterranean  ways  of  our  dties. 
towns,  and  dwellings."  i 

Palladio  says,  "  The  great  com- 
mon sewer  or  the  general  receiver 
or  sink  of  all  the  filth  of  Rome 
was  near  the  Senatorian  bridge, 
called  S.  Marca, — a  performance  of 
Tarquinius  Superbus.   Authors  tell 


SEX 


SHEERS. 


SHI 


strange  things  of  its  largeness,  viz. 
that   a  full  laden  hay-cart  could 
drive  through  it :  upon  measuring, 
I  have  found  it  to  be  16  feet  dia- 
meter.   Into  this  all  other  sewers 
of  the  city  do  empty  themselves, 
which  is  the  reason  that  sturgeons 
taken  between  the  Senatorian  and 
Sublician  bridges  are  better  than 
others,  feeding  on  the  filth  coming 
out  of  this  great  sewer.'' 
Seaetantj  in  geometry,  the  sixth  part 
of  a  circle ;  in  navigation,  &c.,  an 
astronomical  instrument  made  like 
a  quadrant,  but  containing  only 
sixty  degrees 
Shqfif  in  architecture,  the  body  of  a 
column  or  pillar;  the  part  between 
the  capital  and  base.   In  mediaeval 
architecture  the  term  is  applied  to 
small  columns  clustered  round  pil- 
larSy  or  used  in  the  jambs  of  doors 
and  windows. 
Shaft,  in  mill-work,  a  large  axle,  in 
contradistinction  to  a  small  one, 
which  is  called  a  spindle :  thus  we 
say,  *  the  shaft  of  a  fly-wheel,'  'the 
spindle  of  a  pinion.'     Shafts  are 
said  to  be  lying  when  they  are  in 
a  horizontal  direction,  and  vertical 
when  they  are  upright 
Shaft,  in  mining,  a  sinking  or  pit, 
either  in  the  lode  or  through  the 
country 
Shqfted  impott :  according  to  Profes- 
sor WiUis,  **  those  imposts  which 
have    horizontal    mouldings,    the 
sections  of  the  arch  above  and  of 
the  shaft  or  pier  below  such  hori- 
zontal' mouldings  being  different." 
The  latter  point  is  the  distinction 
between  what  he  t^rms    shafted 
and  banded  imposts :  "  in  banded 
imposts,  the  sections  above  and 
below  the  impost  -  moulding  are 
alike,  the  shaft  or  pier  seeming  to 
pass  through  its  capital." 
ShaJtenn  plank  or  timber  which  is  full 
of  clefts,  and  will  not  bear  caulk- 
ing or  fastening ;  generally  called 
$haJltey 
Shambles,  stalls  on  which  butchers 
expose  their  meat  for  sale.    The 
shambles,  or  market-place  for  the 

403  " 


sale  of  fiesh,  at  Frankfort  on  the 
Maine,  is  a  curious  and  ancient  ex- 
ample of  early  shambles 

Shank,  the  space  between  the  chan- 
nels of  a  triglyph 

Shank-painter,  a  chain  bolted  to  the 
top-side  abaft  the  cat-head,  to  lower 
the  anchor  of  a  ship 

Sheave,  in  mechanics,  a  solid  cylin- 
drical wheel,  fixed  in  a  channel 
within  a  block,  and  moveable  about 
an  axis ;  being  used,  in  connection 
with  suitable  tackle,  to  raise  heavy 
weights,  or  to  increase  the  me- 
chanical powers  applied  to  remove 
any  load 

Sheers,  in  mining,  two  very  high 
pieces  of  wood,  placed  in  nearly  a 
vertical  position  in  each  side  of  a 
shaft,  and  united  at  the  top,  over 
which,  by  means  of  a  pulley,  passes 
the  capstan  rope :  this  is  for  the 
convenience  of  lifting  out,  or  lower- 
ing into  the  shaft,  timber  or  other 
things  of  great  length  and  weight 

Sheers,  in  ship-building,  &c.,  are 
masts  or  large  spars  set  across  each 
other  at  the  upper  ends,  by  which 
contrivance  very  heavy  bodies,  such 
,  as  frame-timbers,  masts,  &c.,  are 
raised 

SAetfr-Attfitjin  the  navy,an  oldseventy- 
four  cut  down  to  the  lower  deck, 
and  fitted  up  with  a  pair  of  sheers, 
for  the  purpose  of  taking  out  the 
lower  masts  of  ships  preparing  for 
sea 

Sheer-stroke,  the  strake  under  the 
gunwale  in  the  top-side ;  it  is  ge- 
nerally worked  thicker  than  the 
rest  of  the  top-sides,  and  scarfed 
between  the  drifts 

Sheet,  in  naxdgation,  a  rope  fastened 
to  one  or  both  comers  of  a  sail,  to 
extend  and  retain  it  in  a  particular 
situation 

Sheet  Anchor,  in  navigation,  the 
largest  anchor  of  a  ship 

Sheriff* s  Posts,  two  ornamental  posts 
or  pillars,  set  up  one  on  each  side 
of  the  house  of  a  sheriff  or  chief 
magistrate 

Shift,  the  time  a  miner  works  in  one 
day 


SHI 


SHINGLE. 


SHI  I 


Shtft,  of  timber  or  pknk,  is  oyer 
launching  withouteitherpiece  being 
reduced,  as  the  timbers  of  the 
firame,  or  plank  in  the  bottom 

Shingle,  coarse  sand  and  pebbles  de. 
posited  by  the  surge,  accumulating 
in  banks  and  forming  dangerous 
shoals.  Lieut.-Colonel  Reid,  in  the 
second  Tolume  of  the  *  Professional 
Papers'  of  the  Corps  of  Royal  En- 
gineers,  makes  the  following  obser- 
vations on  the  moving  of  the  shingle 
of  the  beach  along  the  south  coast 
of  England : 

''The  prevailing  winds  being 
westerly,  and  the  highest  seas  roll- 
ing from  the  south-west,  the  peb- 
Ues  of  the  beach  are  gradually 
carried  to  the  eastward,  and  a  con- 
stant supply  is  famished  by  the 
filling  away  of  the  cliffs.  On  this 
coast,  therefore,  groins  so  con- 
structed as  to  prevent  the  moving 
shingle  from  pressing  to  the  east- 
ward cause  an  accumulation  of 
pebbles. 

"  It  has  been  ascertained,  from 
observation,  that  the  pebbles  of  the 
Devonshire  coast  are  forced  to  the 
eastward,  along  the  coast  of  Dov- 
setshire,  as  far  as  the  Chesil  Bank. 
The  stone  pier  of  Lyme  Regis,  called 
the  Cobb,  does  not,  as  might  have 
been  expected,  arrest  their  pro- 
gress; for,  in  south-west  storms, 
they  are  driven  over  the  pier,  and 
the  crews  in  the  harbour  have  had 
to  quit  the  decks  of  their  vessels, 
on  account  of  the  stones  driven 
over  the  pier  falling  on  the  men. 
On  this  account,  within  a  few  years, 
a  high  wall  has  been  constructed 
to  stop  the  progress  of  the  shingle 
at  this  point.  The  natural  conse- 
quence to  be  expected  from  this 
wall  is,  that  the  shingle  will  accu- 
mulate on  the  west  side  of  Lyme 
Regis  pier,  until  it  shall  roll  round 
the  pier-head,  as  at  the  harbour  of 
Dover. 

"  The  Chesil  Bank  is  not  com- 
posed of  calcareous  pebbles,  (as 
stated  in  a  work  of  deservedly  very 
high  reputation,)  but  mostly  con- 


sists  of  silidous  atones,  worn  to  a 
very  remarkable  degree  of  uniform- 
ity of  shape  and  also  of  «ze  (when 
tfUcen  from  the  same  point)  by  long 
attrition  upon  the  coast.  The 
largest  pebbles  have  been  canied 
furthest  to  the  eaat ;  and  the  regu- 
larity with  which  they  are  arranged, 
according  to  their  size,  is  verj  re- 
markable. 

"  The  progress  of  the  shingle  is 
here  first  arrested  by  the  Isle  of 
Portland,  owing  to  the  projection 
of  that  point  of  land  in  a  line  some- 
what to  the  westward  of  south,  and 
the  shingle  bank  stops  just  where 
the  land  trends  in  a  south-west 
direction. 

"The  Chesil  Bank,  at  that  part 
of  it  nearest  the  Isle  of  Portland, 
is  from  20  to  30  feet  above  the 
ordinary  high-water  mark.  On  the 
west  side  it  is  steep,  and  the  water 
deep  close  to  the  shore ;  but  on  the 
east  side  it  has  a  gentle  slope,  with 
a  base  of  200  yards,  to  the  abo?e 
height  of  20  or  30  feet. 

<<  This  gentle  slope  on  the  nit 
side  is  owing  to  the  accumulation 
of  water  on  the  opposite  side  during 
westerly  gales,  which  finds  a  passage 
through  the  gravel  bank,  washing 
it  into  little  ravines,  and  carrying 
down  stones  by  its  current.  In 
very  severe  storms  the  sea  washes 
over  this  bank ;  and  it  did  so  on 
the  23rd  of  November,  1824. 

"A  dangerous  shoal  of  coarse 
sand,  called  the  Shambles,  which 
lies  off  the  south-east  point  of  the 
Isle  of  Portland,  is  in  all  probability 
formed  by  the  tides ;  but  the  Chesil 
Bank  is  formed  by  the  waves  break- 
ing on  the  shore  in  south-west  gales; 
and  it  is  important  that  these  two 
causes,  and  their  resulting  conse- 
quences, should  always  be  sepa- 
rately considered. 

**  Silicious  or  very  hard  pebbles 
only  withstand  long  rolling  on  the 
beach,  whilst  calcareous  stones 
soon  become  ground  into  sand.  As 
the  silicious  pebbles  do  not  pass 
round  Portland  Island,  sand  only 


Kl 


SHINGLE. 


SHI 


is  faund  on  the  shore  of  Portland 

Roads ;  and  it  it  calcareous,  effer- 

vescmg  strongly  with  muriatic  add. 

**  Scarcely  any  grairel  is  to  be 

seen  between  Portland  Roads  and 

Weymouth.     Within  the  Aberga- 

venny,  an  East  India  ship,  which 

sunk  thirty  years  ago  in  the  mouth 

of   We3rmouth  Bay,  there   is   no 

gravel,  and  but  little  sand.     East 

of  Weymouth  it  again  begins  to 

collect;  but  each  little  headland, 

acting  as  a  groin,  retains  much  of 

it  in  the  small  bays.    Round  St. 

Alban'a  Head  its  action  has  not 

been  observed,  but  at  Christchurch 

the  quantity  is  considerable,  and  at 

Hurst  Castle  it  is  very  large. 

'<  The  Isle  of  Wight,  and  the 

strong  current  running  through  the 

Needles,  here  again  a  second  time 

stop  its  eastward  movement;  and 

it  forma,  nearly  in  the  mid-channel, 

a  shoal  called  the  Shingles,  the 

east^nmost  end  of  which  (by  the 

action  of  the  westerly  winds  on  one 

side,  and  the  current  of  the  Needles 

on  the  opposite,)  becomes  heaped 

up  above  high-water  mark  into  an 

island,  varying  in  shape  and  size 

VTith  every  storm,  and  sometimes 

disappearing  altogether. 

'*  The  pebbles  coming  from  the 
westward  must  be  driven  across  the 
north  channel  to  this  bank;  but 
they  do  not  pass  across  the  south 
and  principal  channel  of  theNeedles 
to  the  Isle  of  Wight,  as  is  evident 
from  local  inspection ;  for  those  of 
the  Isle  of  Wight  are  of  a  different 
colour,  being  black  flints  ixovo.  the 
chalk,  whereas  those  on  the  side  of 
Hurst  Castle  are  generally  yellow. 
**  The  effect  of  the  prevailing  wind, 
in  driving  the  gravel  along  the  coast 
from  west  to  east,  is  not  less  evident 
on  the  south  of  the  Isle  of  Wight 
than  elsewhere.  It  passes  eastward 
•  until  it  reaches  Sandovm  Bay,  where 
the  artificial  groins,  kept  up  at  con- 
siderable cost,  arrest  a  certain  por- 
tion; but  the  surplus  is  poured 
over  these  groins,  and,  falling  on 
the  east  side,  continues  its  course. 


''The  gravel  which  passes  Ports- 
mouth  does  not  appear  to  come 
from  the  westward  of  Hurst  Castle, 
for  the  shores  just  within  the 
Needles  are  mud  vnthout  stones. 
A  new  system  commences  within 
the  Solent.  A  large  quantity  of 
shingleis  frimishedfrom  thegravelly 
soil  of  the  south  coast  of  Hampshire; 
and  this  shingle  is  likewise  driven 
eastward,  sometimes  retoming  west- 
ward when  easterly  vrinds  prevail, 
but  the  balance  of  its  progress  is 
always  towards  the  east. 

<<  Hurst  Castle,  Calshot  Castle, 
and  Blockhouse  Fort,  Portsmouth, 
all  stand  on  similar  tongues  of 
shingle,  formed  on  the  west  sides 
of  their  respective  passages  by  the 
prevailing  westerly  winds. 

''At  Hurst  Castle  the  gradual 
additions  to  the  end  of  the  strip  of 
shingle  may  be  plainly  seen;  for 
Nature  there  records  her  own  his- 
tory In  a  very  visible  manner.  An 
ordnancelanding-place  30  feet  long, 
which  vras  constructed  in  1806, 
and  stood  in  the  sea,  became  en- 
tirely buried  in  gravel;  and  many 
succeeding  lines  of  high-water  mark 
may  be  distinctly  traced  to  the 
eastward  of  Hurst  Castle. 

"  Similar  traces  of  many  former 
lines  of  high-water  mark  are  also  to 
be  seen  near  Southsea  Castle ;  and 
immediately  on  the  west  of  Fort 
Monkton,  six  distinct  lines  of  high 
water  may  be  counted ;  and  some 
of  these  probably  belong  to  very 
remote  periods  of  time. 

"The  dnection  of  the  line  of 
coast,  vnth  reference  to  the  pre- 
vailing gales,  seems  to  determine 
where  the  shingle  will  accumulate, 
or  where  the  sea  will  be  most  likely 
to  encroach  upon  the  land;  and 
seems  to  be  one  of  the  most  im- 
portant points  to  study  aa  regards 
the  subject  of  openingbar-harbours. 

«  The  soutb-eaaterly  direction  of 
the  beach  at  Soutbsea  would  appear 
to  be  one  of  the  causes  why  the 
entrance  of  Portsmouth  Harbour  is 
kept  as  dear  as  it  is,  by  the  current 


405 


s5 


SHI 


SHINGLE. 


SHI 


mimmg  out  of  it ;  for  this  direction 
of  the  Itnd  prevents  the  witer  from 
spreading  itself  on  both  sides,  mt 
the  ebbing  tide,  as  it  does  at  the 
entrance  (xf  Langston  Harbonr,  oirer 
banks  of  graYcl ;  and  this  direction 
at  Soothsea  appears  just  sufficient 
to  allow  the  shingle  to  be  set  to  the 
eastward  by  the  prevailing  gales. 

**  It  well  deserves  consideration, 
whether  embankments  (onthe  south 
coast  of  England)  run  out  on  the 
eastward  of  bar-harbours,  in  a  line 
parallel  to  the  line  formed  by  nature 
on  the  east  side  of  Portsmouth 
Harbour,  would  not  lead  to  a  simi- 
lar effect  as  that  produced  there  in 
keeping  open  one  principal  channel. 
By  a  proper  system  of  groins  on  the 
west  side  of  such  harbours,  shingle 
coming  from  the  westward  would 
be  stopped,  and  much  of  the  ma- 
terials which  now  form  the  bars 
might  be  arrested  in  their  course. 
'The  slope  of  the  beach  is  flatter 


tf 


after  a  aootheriy  gale^andita  sverage 
slope  is  abont  1  foot  in  9. 

**  If  groins  are  not  carried  £u- 
enongh  in-land,  the  aea  in  south- 1 
west  storms  (on  the  south  coast)  , 
will  Inreak  round  and  limnlate  them. 
If  they  are  not  hi|^  enough  at  fai^- ' 
water  mark,  the  gravel  will  be  car- 
ried over  them  to  the   eastward; 
and  if  they  are  too  short,  it  will 
pass  round  the  outo-  end  of  them. 

"During  southeriy  gales,  it  is 
frequently  said,  that  the  gravel  is . 
'  carried  into  the  sea,'  because  the 
receding  waves  draw  it  down ;  but 
it  is  again  driven  back,-and  if  the  < 
wind  be  soath«west  it  ia  aet  to  the  ' 
eastward. 

**  The  annexed  figure,  in  which  a ', 
pebble  (a)  passes  to  (^),  following 
a  course  indicated  by  the  alphabet!,  i 
cal  order  of  the  letters,  will  explain  ' 
what  is  here  meant,  and  show  the 
way  in  which  the  gravel  pasaes  by 
groins  which  are  too  short. 


Weat. 


a 

9 


High- water  mark. 


Baat. 


5  V' 


AC 


ii 


I 
I 
I 
I 
I 
« 


A 


¥ 


.'g- 


id 


Foot  of  the  ilope  of  gnvel. 


'*  From  this  figure  it  will  also  be 
understood,  why  a  single  plank  re- 
moved from  a  wooden  groin  will 
cause  the  beach  at  such  place  of 
removal  to  be  carried  on  forward ; 
and  hence  the  importance  of  con- 
structing groins  of  materials  not 
liable  to  such  accidents. 

**  The  point  of  shingle  on  which 


Calshot  Castle  now  stands  was  once 
an  island,  and  called,  in  1717, 
Crown  Island;  since  which  time 
the  opening  has  filled  inwithgraT(>l. 
The  point  on  the  west  side  of 
ChiistchurchHarbourisnow  length- 
ening annually ;  and  the  mouth  of 
that  harbour  and  its  bar  become 
every  year  more  and  more  removed 


406 


SHR 


winl  until  the  water  from 
estiuTjiball  re-opea  s  fresh  passage 
for  itself  in  ■  more  direct  line,  as 
the  water  seems  to  have  done  at  the 
harbour  of  Shoreham. 

"At  sucb  harbours  m  Portsmouth 
it  would  be  desirable,  by  means  of 
the  apparatu»  for  enabling  persons 
to  descend  and  eiamine  the  bed  of 
the  sea,  to  obsecve  and  determine 
the  precise  mode  of  the  acli 
the  shingle  at  the  entrance  of  har. 

"  The  sand  being  blown  by  the 
wind,  as  well  a&  driven  bj  the  surge, 
it  frequently  covert  the  coarser 
shingle,  where  it  is  retained  by  the 
ecrex  armaria,  a  grass  which  roota 
at  every  joint," 

(Much  valuable  infonnation  on 
the  lubject  of  encroachments  of  the 
tea  upon  the  land  wilt  be  found  in 
Lyell's '  Geol<^.') 

Shinglet,  m  house-building,  small 
pieces  of  wood  sawed  to  a  certain 
scantling,  used  in  roofing,  instead 
of  tiles  or  slates 

Skiltim  vmed,  a  valuable  kind  of  tim- 
ber, of  which  Moses  made  the 
greater  part  of  the  tables,  altars, 
and  planks,  belon^g  to  the  taber- 
nacle: it  grows  in  the  deserls  of 
Arabia,  and  is  Uke  while-thorn  in  its 
colour  tad  leaves,  but  not  in  size, 
as  the  tiee  ia  so  large  that  it  affords 
very  long  planks :  the  wood  is  hard, 
tough,  smooth,  without  knots,  and 
extremely  beautiful ;  so  that  the 
rich  aud  curious  make  screws  of  it 
for  their  presses  ^ 

SAhen,  in  navigation,  the  little  round 
wheels,  of  wood  or  metal,  in  which 
the  rope  of  a  pulley  or  block  runs 

SAaiet,  pieces  of  plank  put  under  the 
shores  where  Uiere  are  no  grotwd- 
ways 

Sharf.  pieces  of  timber  Hied  to  sup- 
port a  ship 

SArino,  tombs,  or  decorated  mono- 
ments  of  ornamental  tabernacle- 
work,  as  they  are  applied  to  the 
entombment  of  royal  and  noble 
persons:  severalvery  fine  examples 
exist  in  the  cathedrals  and  abbey 


SHU 


SKRSENS. 


SKR 


churches :  the  term  is  also  applied 
to  a  cabinet  in  which  sacred  things 
are  deposited 

Shuni,  a  term  applicable  to  the  ma- 
nagement of  railway  trains,  to  re- 
move a  carriage  or  train  off  the  main 
line.  When  an  engine,  carriage^  or 
train  is  moved  off  the  main  line 
to  a  siding,  it  is  then  said  to  be 
'  shunted.'  It  is  most  probably  de- 
rived from  the  word  *  shun  :'  in  the 
old  English  Romance  *  Mort  Ar- 
thure '  we  find  the  word  'schunte' 
used  in  this  sense,  to  put  off;  and 
in  other  early  Works  the  word 
'  shunted '  may  be  found,  with  the 
meaning,  to  move  from. 

Side  ehaiiUt  chains  and  hooks  fixed 
to  the  sides  of  the  tender  and  en- 
gine for  safety,  should  the  central 
drag.bar  give  way 

Sidereal  year^  that  space  of  time 
which  astronomers  compute  the 
sun  is  moving  from  any  fixed  star 
till  it  returns  to  it  again,  reckoned 
at  365  days,  6  hours,  and  almost 
10  minutes 

Signal  lampSf  railway  lamps  with  a 
buirs-eye  glass  in  front.  Each 
lamp  has  a  recess  between  the 
burner  and  bull's-eye,  for  dropping 
in  any  particular  coloured  glass, 
according  to  the  light  which  is  to 
be  shown.  The  lamp  has  also  re- 
cesses for  holding  these  glasses,  so 
that  the  engine-man  can  at  once 
pick  out  a  red,  green,  or  blue  glass, 
and  put  it  in  front  as  he  may  re- 
quire it. 

SiU^  the  lower  horizontal  frame  of  a 
door  or  window ;  a  threshold 

Siltf  in  hydrography,  &c.,  mud  depo- 
sited by  riyers,  tides,  &c.,  generally 
in  still  parts  or  eddies,  and  also  in 
lakes  or  hollows  filled  with  still 
water 

Siher  is  sometimes  found  in  the  me- 
tallic state,  and  as  chloride  and 
sulphide,  besides  alloyed  with  gold, 
copper,  and  other  metals.  It  is 
a  pure  white  brilliant  metal,  of 
great  ductility,  capable  of  being 
drawn  out  into  very  fine  wires.  It 
melts  at   18  73^     and    absorbs  a 

408 


large  quantity  of  oxygen,  which, 
disengaging  on  cooling,  gives  it  a 
white,  frosty  appearance:  when 
impure,  it  does  not  do  so.  It  is  a 
metal  used  in  great  abundance  as  a 
coin  in  all  countries,  also  for  plate, 
for  vases,  candelabra,  cups,  &c. 

Sinking^  in  mining,  digging  down- 
wards; in  rising  and  sinking  a 
shaft,  one  set  of  men  sink  firom  a 
certain  level,  while  another  set  rises 
from  a  lower  level  to  meet  them 

Sgtarium^  in  the  time  of  the  Romans, 
a  piece  of  tapestry  stretched  on  a 
frame,  which  rose  before  the  stage 
of  the  theatre 

Siphon,  or  Syphon,  in  hydraulics,  a 
crooked  pipe  through  which  liqnors 
are  conveyed 

5lw«oo  is  one  of  the  most  Talnable 
timber-trees  of  India,  and  with  the 
Maul  is  more  extensively  used  than 
any  other  in  north-west  India.  The 
ship-builders  in  Bengal  select  it 
for  crooked  timbers  and  knees ;  it 
is  remarkably  strong;  its  colour  is 
a  light  grayish  brown  with  dark-co- 
loured veins. 

%rindle'tree,  a  shrubby  tree,  with 
a  yellow  wood  similar  to  the  En- 
glish box-wood:  it  is  turned  into 
bobbins  and  common  articles 

Site,  the  situation  of  a  building ;  the 
plot  of  ground  on  which  it  stands 

Site,  in  limdscape,  signifies  the  view, 
prospect,  or  opening  of  a  country, 
derived  from  the  Italian  word  sito, 
situation ;  and  it  is  in  use  among 
painters,  as  being  more  expres- 
sive 

Sketch,  a  slightly  made  picture,  in 
which  the  general  effect  is  attended 
to,  but  not  always  the  details,  and 
from  which  more  finished  works 
are  painted :  so  also  with  sketches 
in  architecture,  giving  the  correct 
outline  of  a  building  without  filling 
up  with  the  detail. 

Skew,  or  AakeWt  as  Upplied  to  masons' 
work,  an  oblique  arch 

Skirting,  a  narrow  board  forming  a 
plinth  to  an  internal  wall 

Skreena  were  either  of  needle-work 
or  painted :  in  the  time  of  Heniy 


SKY 


SLIDE-REST. 


SLI 


YIII.  is  noticed  a  skreen  as  a  new 
year's  gift  from  Luke  Homebonnd, 
a  painter,  to  that  monarch 
SkylightM^  glass  frames  placed  in  a 
roof  with  one  or  more  inclined 
planes  of  glass 
Slaking  of  Lime.  Qoick-limey  taken 
as  it  leaves  the  kiln,  and  thrown 
into  a  proper  quantity  of  water, 
splits  with  noise,  puffs  up,  produces 
a  large  disengagement  of  slightly 
caustic  vapour,  and  falls  into  a 
thick  paste.  So  much  beat  is  pro- 
duced in  slaking,  that  part  of  the 
water  flies  off  in  vapour.  If  the 
quantity  of  the  Hme  slaked  be  great, 
the  heat  produced  is  sufficient  to 
set  fire  to  combustibles:  in  this 
manner  vessels  loaded  with  lime 
have  sometimes  been  burnt.  When 
great  quantities  of  lime  are  slaked 
in  a  dark  place,  not  only  heat,  but 
light  also,  is  emitted.  The  specific 
gravity  of  pure  lime  is  3*08. 
Slatef  an  argillaceous  stone,  readily 
spUt,  and  employed  to  cover  build- 
ings, and  also  for  other  purposes : 
it  is  quarried  in  large  pieces 
Slating  is  employed  by  builders  for 
covering  in  the  roofs  of  build- 
ings. The  slates  principally  in  use 
in  London  are  brought  from  North 
Wales. 
Sleepers^  pieces  of  timber  employed 
to  support  others,  and  laid  asleep, 
or  with  a  bearing  along  their  own 
length :  sleepers  denote  more  par- 
ticularly  those  timbers  which  are 
placed  lengthwise  on  walls  to  sup- 
port the  joists  of  a  floor;  they 
are  employed  on  railroads  as  longi- 
tudinal bearings  for  the  rails  to 
rest  upon 
SieeperSf  or  TVansome-kneeg,  are  fixed 
withinside  a  ship  abaft,  one  arm 
laying  on  the  foot  waleing,  and  the 
other  extended  up  the  transoms 
SlicMngSf  narrow  veins  of  ore 
Slidcy  a  vein  of  clay,  which,  intersect- 
ing a  lode,  causes  a  dislocation  ver- 
tically 
SUde-reat.  This  apparatus,  the  in- 
vention of  Mr.  Henry  Maudslay,  is 
I     of  the  utmost  importance  for  per- 

409 


fecting  and  accelerating  the  con- 
struction of  machinery.     Before 
its  invention,  cylindrical  turning 
was  a  work  of  manual  labour,  and 
was  ^attended  with  so  much  diffi- 
culty and  expense,  when  the  cylin- 
ders were  either  large  in  diameter 
or  of  moderate  length,  that  it  was 
necessary  to  avoid  using  them  in 
many  cases;   and  plane   surfaces 
being  even  still  more  expensive, 
in  consequence  of  the  very  imper- 
fect  and  laborious  operations  of 
chipping  and  filing  them,   many 
very  valuable  inventions  could  not 
be  carried  into  effect  on  account 
of  the  inaccuracy  and  expense  at- 
tending their  construction.     The 
invention  of  the  slide-rest,  forming 
an  all-important  part  of  that  of 
the  planing  machine,  has  entirely 
removed  both  of  these  difficulties, 
and  cylindrical  turning  and  planing 
are  now  the  cheapest  and  most 
perfect  of  mechanioEd  operations. 

The  office  of  the  slide-rest,  as 
applied  to  lathes  and  turning 
machines,  is  to  holdf  engage^  and 
direct  the  tuming-tool,  and  it  may 
be  kept  in  motion  either  by  hand 
or  by  self-acting  machinery. 

When  applied  to  a  small  lathe, 
it  is  generally  moved  by  hand ; 
but  in  large  machines  for  heavy 
work,  where  the  time  of  action  is 
considerable,  it  is  moved  by  ma- 
chinery attached  to  the  lathe.  The 
work  to  be  turned  being  placed  in 
the  usual  way  between  the  two 
centre  pieces  of  the  lathe,  the 
lower  part  of  the  slide-rest  is  fixed 
under  it  on  what  is  called  the  bed 
of  the  lathe :  the  use  of  this  part  of 
the  slide  is  to  move  the  tool  to  or 
from  the  work,  which  it  effects  by 
means  of  a  slide,  at  right  angles  to 
the  work,  moved  by  a  screw  and 
handle :  this  slide  has  fixed  upon  it, 
by  a  svrivel  joint,  the  upper  part 
of  the  apparatus. 

The  upper  part  has  also  a  slide 
moved  by  a  screw  and  handle,  and 
generally  placed  at  right  angles  to ; 
the  lower  slide :  the  principal  use 


su 


SLIDE-VALVE. 


3L1 


of  thii  upper  slide  ii  to  move  the 
cutting-tool  which  ii  fixed  upon  it 
pRTsllel  to  the  centre  line  of  the 
lathe ;  but  it  ctn  be  «o  placed,  b; 
■id  of  the  iwivel-jmnt,  u  to  caate 
the  tool  to  advance  at  an;  Squired 
angle  with  the  centre  line  of  the 
lathe.  Thus  tno  diiect  luovement] 
are  obtained  :  the  first  to  let  the 
tool  to  the  woik,  and  the  second 
to  moye  it  either  to  the  right  or 
left,  in  a  line  parallel  with  the  work, 
or  at  any  given  angle  with  the  first. 
The  slide-rest  principle  enters 
largely  into  the  coiutruction  of  all 
kindi  of  machinery,  from  the  moat 
minute  to  mHChinct  of  vast  m^pii- 
tude,  where  by  its  aid  ponderous 
masses  —  such  foi  instance  as  rail- 
way tum-tables  36  feet  in  diame- 
ter— are  operated  upon  with  a 
predsion  DnattaioBble  bf  any  other 


Slide-vah)e,ln  locomotive en^Ba,iht 
valve  placed  in  the  itcam-dxit  to 
work  over    the   ateam.pDrts.    Ii 
regulate!  the  admiasion  of  steu 
to  the  cylinder  from  the  bciltr, 
and  the  escape  of  the  sleim  fm 
the   cylinder   to  the  atmospb— 
Its  form  is  that  of  an  aich  ia 
centre,  with  a  flat  fKX  all  ni 
to  keep  it  iteam-tight  on  the 
of  the  steam-portB.     It  is  b;  &t 
arched  part  tlut  the  ateam 
to  the  atmosphere.     It  ii 
umple  valve,  and  auswen  i 
pose  well,   with    one   draw-lwAi 
namely,  the  pressure  of  the  slon 
upon  it  being;  unbalanced  by  u;    I 
counter.pressure.      Numerons  st 
tempts  have  been  made  to  reliCTt 
this  pressure,  aome  of  which  it  ii 
hoped  will  he  successful-    I"  i* 
tionary  engines   the   ccmtrivsiica 
differ  materially,  aa  shown  btio*- 


SLI 


SLIDE-VALVE. 


SLI 


Fig.  1  represents  in  section  the 
cylinder,  piston,  and  slide :  S  is  the 
mouth  of  the  steam-pipe  coming 
from  the  boiler ;  e  is  the  pipe  lead- 
ing to  the  condenser ;  t  is  the  rod 
which  is  attached  to  the  slide, 
moving  through  a  stuffing-box,  m  n. 
This  slide  is  represented  in  longi- 
tudinal section,  separately,  in  fig.  3, 
and  in  transverse  section  in  fig.  4. 
In  the  position  of  the  slide  repre- 
sented in  fig.  1,  the  steam  passing 
from  the  boiler  enters  at  S,  and 
passes  to  the  bottom  of  the  cylin- 
der through  the  opening  ^,  where 
it  acts  below  the  piston,  causing  it 
to  ascend.  The  steam  which  was 
above  the  piston  escapes  through 
the  opening  at  a,  and  descending 
through  a  longitudinal  opening  in 
the  sUde  behind  the  mouth  of  the 
steam-pipe,  finds  its  way  to  the 
pipe  tf,  and  through  that  to  the 
condenser. 

When  the  piston  has  reached 
the  top  of  the  cylinder,  the  slide 
will  have  been  moved  to  the  posi- 
tion represented  in  fig.  2.  The 
steam  now  entering  at  S  passes 
through  the  opening  a  into  the 
cylinder  above  the  piston,  while  the 
steam  which  was  below  it  escapes 
through  the  opening  b  and  the 
pipe  e  to  the  condenser. 

The  form  of  the  valve, 
from  which  it  derives 
its  name  of  D-valve,  is 
represented  in  fig.  4. 
The  longitudinal  open- 
ing  through  which  the 
steam  descends  then 
appears  in  section  of  a 
semicircular  form.  The  packing  at 
the  back  of  the  slide  is  represented 
at  k\  this  is  pressed  against  the 
surface  of  the  valve-box. 
SUdC'Valoe  lap,  Outsidct  in  locomotive 
engines,  that  portion  of  valve  which 
would  overlap  the  steam-portswhen 
placed  over  them.  If  the  steam- 
ports  measure  8  inches  over  all  the 
ports,  and  the  valve  be  10  inches 
hroad,  this  would  be  an  overlap  of 

1  inch  on  each  side  of  the  ports, 

■ ' ' '  — 


and  is  called  the  'lap'  of  the  valve. 
Expansion  was  formerly  regulated 
.  by  the  extent  of  lap  only,  but  it  is 
now  regulated  by  both  the  lap  and 
the  expansion  gear,'  which  gives 
greater  scope  in  doing  so.  Innde 
lap  is  the  portion  of  the  valve  face 
which  would  overlap  the  inside  of 
the  steam-ports  when  placed  over 
them ;  for  if  the  steam-ports  were 
4  inches  from  inside  of  the  one 
port  to  the  inside  of  the  other 
port,  and  if  the  arched  part  of  the 
valve  only  measured  3|  inches 
across,  this  would  give  -^  of  an 
inch  lap  on  each  side,  which  is 
called  inside  lap. 

Slide-valve  leadf  in  locomotives,  the 
width  which  the  steam-port  is  open- 
ed by  the  slide-valve  when  the  pis- 
ton is  at  the  end  of  the  stroke.  It 
varies  from  |^  to  |  an  inch,  accord- 
ing to  the  work  required.  The  lead 
is  obtained  by  fixing  the  eccentric 
on  the  axle,  a  little  in  front  of  the 
crank,  by  which  arrangement  the 
steam-port  is  opened  in  front  of 
the  direction  in  which  the  piston 
is  moving  before  the  latter  has 
completed  its  stroke.  By  these 
means  the  steam-port  is  thrown 
quickly  open  when  the  piston  com- 
mences its  return  stroke,  and  has 
at  once  the  full  pressure  of  the 
steam  against  it. 

Slide-valve  travel^  the  distance  which 
the  slide-valve  travels  in  one  direc- 
tion for  each  stroke  of  the  piston. 
This  is  from  4  to  5^  inches  gene- 
rally, but  is  reduced  by  each  varia- 
tion of  the  expansion  gear,  and  its 
travel  is  taken  for  both  the  front 
and  back  strokes  of  the  piston  for 
each  notch  where  the  handle  is 
fixed.    The  up  and  down  quarter- 
revolutions  of  the  crank  do  not 
equally  draw  the  piston  the  half 
length  of  the  cylinder,  and  this 
and   the    expansion  gear    so  far 
affect  the  working   of  the   slide  | 
that  it  is  necessary  to  take  the  ' 
front   and   back   stroke  working 
separately. 

Setting  thesUde-valve:  the  epcen- 


SLI 


SLIDING  RULE. 


SLI 


trie  is  brought  as  much  before  the 
crank  as  to  give  the  required  lead 
to  the  slide-yalTe  when  the  crank 
is  on  the .  centre,  that  is,  in  a 
straight  line  with  a  cylinder.    The 


handle  is  then  moved  to  each  sepa- 
rate notch,  and  the  position  of  the 
slide  and  piston  carefully  taken  for 
each  variation.  These  are  then 
recorded  in  the  following  manner : 


SUde-valve  and  Piston  Motion^  Regitter, — Working  of  expansion  gear, 
Engine, [ 1 85 


Inchea. 

Inches. 

Diameter  of  cylinders    .    . 
Length  of  stroke  .... 
Size  of  steam-port    .     .    . 

18 

Outside  lap  of  valve  . 
Inside  lap  of  valve     . 
Size  of  exhaust-port 

•  • 

•  • 

1 

24 

1^ 

15x2 

•           • 

15x3* 

I 
S 

Steam  cut 

Exhaust 

Compres- 

Steam-port 

f  notch  in  revc 
andle  guide. 

• 

m 

'Si 

otf. 

open*. 

lion  begins. 

opens. 

"5  . 
S.9- 

aSMARKB. 

u 

1- 

V 

« 

■  o 

V 

MS 

1. 
^1 

o.a 

£« 

3-5, 

0  -s 

•R  • 

n.2 

M.S 

fl-S 

M.S 

M  tf 

O  CO 

jz;.2 

^1 

£•8 

i^ 

jS'S 

^^ 

(S's 

i6's 

.3  3 

Balance  piston 
for   slide- 

In. 

In. 

In. 

In. 

In. 

In. 

In. 

In. 

In. 

In. 

In. 

Tolves. 

1 

2 
3 
4 
5 

4i 

19* 

19 

22| 
22^ 

22| 

2H 

22i 
22 

21* 
20 
18 

22^ 
211 

1* 

IJ 

H 

1 

18^    18 

lA 

If 

4 

u 

16»;16T<ir 

21i 
20A 
18tV 

21i 

21 
19* 

3^ 

13f   13* 

9i     10 

17* 

A 

6 

m 

u 

15 

15* 

15* 

a 

a 

Centre  notch.  1 

5A     6 

15 

1 

The  above  measurements  are  carefully  taken  and  registered  by  the  mechanic 

who  sets  the  slide-valves. 


SUde-vahe  rod  guide,  in  locomotive 
engines,  a  bracket  fixed  to  the 
boiler,  the  lower  end  of  which  is 
fitted  for  the  slide-valve  rod  to 
work  through.  A  set-screw  is  use- 
ful in  this  guide  for  fixing  the  rod 
when  the  valve  has  to  be  discon- 
nected. 

SUde-valve  rod  and  frame,  in  loeo- 
motive  engines :  the  frame  is  fitted 
on  to  the  top  part  of  the  valve, 

412 


and  the  rod  connects  the  frame 
with  the  slide-block,  or  rocking- 
shaft,  according  to  the  description 
of  valve-gear  of  the  particular 
engine 

Slide-valve  motion,  in  locomotive  en- 
gines, a  short  motion  similar  to  the 
piston-rod  motion,  connecting  the 
quadrant  to  the  slide-valve  by 
parallel  guides 

SUding  rtde,  a  rule  constructed  with 


SLI 


SMELTING. 


SME 


logarithmic  lines,  formed  upon  a 
slip  of  wood,  brass,  or  ivory,  in- 
serted  in  a  groove,  in  a  rule  made 
to  slide  longitudinally  therein,  so 
that  by  means  of  another  scale 
upon  the  rule  itself  the  contents  of 
a  surface  or  solid  may  be  known 
SUmes,  mud  containing  metallic  ores, 
mud  or  earthy  partides  mixed  with 
the  ores 
SKt  dealf  a  name  for  inch  and  a  qnar- 

ter-inch  deal  cut  into  two  boards 
Sloop,  in  navigation,  a  small  one- 
masted  vessel,  the  mainsail  of 
which  is  attached  to  a  gaff  above, 
and  to  a  long  boom  below.  The 
word  is  also  applied  to  any  small 
ship. 
Shtice,  in  hydraulics,  a  water-gate,  a 

flood-gate,  a  vent  for  water 
Smelting  is  the  process  of  separating 
metals  from  the  earthy  and  other 
matters  vrith  which  they  are  com- 
bined in  the  state  of  ore.  Of  this 
operation,  as  conducted  upon  the 
ores  of  iron,  copper,  lead,  and  tin, 
the  follovring  is  a  brief  description : 
Smelting  Iroit.  The  reduction  of 
iron  ore  is  effected  in  a  furnace  in 
which,  the  required  intensity  of 
heat  being  obtained  by  a  current  of 
air  driven  rapidly  into  the  furnace, 
has  received  the  name  of  a  blast- 
furnace.  The  kind  of  furnaces  em- 
ployed, the  quantity  of  ore  or  mine, 
as  it  is  termed,  reduced  at  each 
heat,  and  the  peculiar  method  of 
conducting  the  operation,  vary 
widely  in  different  countries  and 
counties,  and  have  some  reference 
in  detail  to  the  precise  quality  and 
composition  of  the  ore  to  be  treated. 
Previous  to  the  year  1740,  the 
smelting  of  ores  of  iron  was,  in 
England,  performed  solely  with  the 
charcoal  of  wood,  the  ores  operated  . 
upon  being  principally  the  brown  I 
and  red  hematites,  or  rich  ores,  I 
that  is,  containing  a  large  proportion 
of  metal  with  a  small  quantity  of 
earthy  materials.  In  the  treatment 
of  this  class  of  ores,  it  may  be  ob. 
served  that  very  little  improvement 
has  yet  been  effected,  the  modem 

413 


processes  having  been  chiefly  ap- 
plied to  the  leaver  ores,  such  as 
blackband,  &c.    The  expensiveness 
and  comparative  scarcity  of  char- 
coal as  a  fuel  for  the  smelting  of 
iron  ores,  induced  those  engaged  in 
the  art  to  attempt  the  substitution 
of  coal  for  wood-charcoal ;  and  by 
the  year  1788,  these  attempts  had 
so  far  succeeded,  that  there  remain- 
ed only  24  out  of  59  charcoal  fur- 
naces,  while  53  furnaces  had  been 
established  in  which  coal,  burned 
into  the  form  of  coke,  was  used  for 
the  smelting  of  the  ore.  Since  that 
date,  the  extension  of  this  process 
has  proceeded   rapidly,    and    the 
total  quantity  of  metal  produced 
has  experienced  a  corresponding 
augmentation.  At  the  present  time, 
the  Backbarrow  Iron  Company  are 
nearly  the  only  smelters  of  iron 
with  wood-charcoal  in  the  kingdom. 
The  two  principal  seats  of  the  iron 
manufacture  in  Great  Britain  are  in 
Staffordshire  and  South  Wales.  In 
the  former  district,  comprising  the 
neighbourhoods  of  Dudley,  Bilston, 
Wednesbury,  &c.,  the  smelting  or 
blast  furnaces  are  constructed  al- 
most wholly  of  bricks.    They  are 
usually  of  a  conical  form  exter- 
nally, and  sometimes  pyramidal,  the 
plan  being  a  square  or  rectangle. 
In  the  interior  they  are  mostly  cir- 
cular in  form,  except  in  that  part 
called  the  hearth.    The  fuel  and 
the  ore  to  be  smelted  are  fed  into 
the  furnace  from  the  top,  and  its 
height  being  from  40  to  50  feet,  an 
ascendingplatform  or  inclined  plane 
is  constructed  for  wheeling  up  the 
barrows  in  which  the  materials  are 
conveyed.  The  pipes  through  which 
the  air  is  driven  into  the  furnace 
(by  a  steam  engine)  are  called  the 
tuyeres,  and  are  usually  two,  but 
sometimes  three  in  number.    The 
relative   quantities  of  coal,   iron- 
stone, and    limestone,  which  are 
put  into  the  smelting  furnaces  of 
Staffordshire  for  the  production  of 
each  ton  weight  of  iron  produced, 
are  about  50  cwt.  of  coal,  50  cwt. 


SME 


SMELTING. 


SME 


I 

when  the  ore  is*  thrown  into  an  { 
arch  formed  nnder  the  sole  of  the  I 
furnace.  The  second  operation,  or  ' 
fusion  of  the  calcined  ore,  is  per- 
formed in  a  luted  furnace,  the  ore 
having  been  spread  unifoimly  over  , 
the  hearth,  and  fluxes,  such  as  lime, 
sand,  or  fluor-spar,  being  added : 
when  required,  although  the  ne- , 
cessity  for  this  addition  is  sought  | 
to  be  obviated  by  a  careful  admix- 1 
ture  of  ores  of  different  qualities, ! 
the  several  earthy  components  of: 
which  shall  serve  as  fluxes  in  the 
fusion  of  the  mass.  These  two 
processes  of  calcination  and  fusion  ; 
are  repeated  alternately  untQ  the ' 
ore  is  completely  freed  from  all  the  ' 
earthy  materials,  and  pure  metal  is ; 
obtained. 

Smelting  Lead,  The  ores  of  lead, ! 
after  being  sorted,  cleansed,  ground, 
and  washed,  are  roasted  in  furnaces, 
which  are  without  any  hiast  or 
blowing  apparatus,  the  ores  being 
separable  from  the  metal  by  its 
great  fusibility.  Several  of  the 
frimaces  are  usually  connected  with 
one  chimney-staUc,  to  which  a 
series  of  flues  about  18  inches  square 
conduct.  The  melted  lead  runs 
freely  from  the  ore  and  is  dravm 
off  into  the  moulds  in  successive 
quantities,  the  ore  being  repeatedly 
turned  over,  and  a  sniall  quantity 
of  coal  added  over  the  burning 
mass  at  each  drawing. 

Smelting  Tin.  This  process  con- 
sists of  the  calcining  or  roasting  of 
the  ores  afterthey  have  been  cleaned, 
sorted,  stamped,  and  washed.  The 
calcining  is  performed  in  a  rever- 
beratory  furnace  from  12  to  15  feet 
long  and  7  to  9  feet  vride.  The 
hearth  of  these  furnaces  is  hori- 
zontal, and  they  have  only  one 
opening,  which  is  in  the  front,  and 
closed  by  an  iron  door.  The  sul- 
phureous and  arsenical  vapours 
which  arise  from  the  ore  are  con- 
ducted by  chimneys  over  the  doors 
of  the  range  of  furnaces  into  hori- 
zontal flues,  in  which  the  acid  is 
condensed.    In  the  process  of  cal- 


of  mine,  previously  calcined,  and 
from  12  to  16  cwt.  of  limestone, 
the  latter  material  being  added  as 
a  flux  to  promote  the  fusion  of  the 
mass.  The  Conegree  furnace,  near 
Dudley,  may  be  instanced  as  a 
good  example  of  a  blast-furnace 
adapted  for  the  economical  smelt- 
ing of  iron  ores.  It  is  54  feet  in 
height,  5  feet  in  diameter  on  the 
hearth,  and  12  feet  above,  widening 
upward  to  a  diameter  of  13  feet 
9  inches,  and  reduced  to  8  feet 
above  the  platform,  on  which  the 
charges  are  delivered.  The  quan- 
tities of  materials  employed  in  this 
furnace  to  make  one  ton  of  pig- 
iron,  are  of  coal  2  tons  and  5  cwt., 
or  of  coke  37  cwt.,  charred  mine 
2  tons  5  to  10  cwt.,  limestone  13 
to  16  cwt. 

Each  charge  delivered  into  the 
furnace  consists  of  9i  cwt.  of  coke, 
12  cwt.  of  charred  mine,  and  4  cwt. 
of  limestone.  At  this  furnace  115 
tons  of  pig-iron  have  been  made  in 
one  week.  The  cyhnder  from  which 
the  air  is  blown  through  the  tuy- 
eres into  the  furnace  is  72^  inches 
in  diameter,  and  the  stroke  is  7  feet 
in  length.  Originally  there  were 
five  tuyeres  for  the  introduction  of 
the  blast,  one  muzzle  being  2^, 
two  others  2^,  and  the  other  two 
2  inches  in  diameter.  S  ubsequently 
these  were  changed  to  four  muzzles, 
of  the  respective  diameters  of  3^, 
2^,  2^,  and  2  inches. 

Smelting  Copper.  Copper  ore, 
as  smeltedin  South  Wales  and  other 
places,  usually  consists  of  pyrites 
(composed  of  sulphuret  of  copper 
and  sulphuret  of  iron  in  nearly 
equal  proportions),  and  vein-stone. 
The  earthy  matters  combined  with 
the  pyrites  are  commonly  sihcious, 
and  the  process  of  smelting  consists 
in  alternate  roastings  and  fusions. 
The  first  of  these  operations  is,  cal- 
cining the  ore  in  furnaces  in  which 
the  heat  is  ap;:lied,  and  increased 
gradually,  till  the  temperature  be 
as  high  as  the  ore  can  support 
without  melting  or  agglutinating, 

414 


SxMO 


SMOKE. 


SMO 


doation,  whidi  occupies  from  12 
to  18  hours,  according  to  the  quan- 
tity of  pyrites  contained  in  the  ore, 
6  cwt.  of  ore  are  treated  at  once, 
and  the  materials  are  stirred  from 
time  to  time,  to  prevent  them  from 
agglutinating. 
Smokey  Prevention  of.  There  is  per- 
haps no  subject  so  difficult,  and 
none  so  full  of  perplexities,  as  that 
of  the  management  of  a  furnace 
and  the  prevention  of  smoke.  Mr. 
Fairbairn,  in  his  Report  to  the 
British  Association  on  the  Con- 
sumption of  Fuel  and  Prevention 
of  Smoke,  observes,  —  "I  have 
approached  this  inquiry  with  con- 
siderable diffidence,  and  after  re- 
peated attempts  at  definite  conclu- 
sions, have  more  than  once  been 
forced  to  abandon  the  investigation 
as  inconclusive  and  unsatisfactory. 
These  views  do  not  arise  from  any 
defect  in  our  acquaintance  with  the 
laws  which  govern  perfect  com- 
bustion, the  economy  of  fuel,  and 
the  consumption  of  smoke.  They 
chiefly  arise  from  the  constant 
change  of  temperature,  the  varia- 
ble nature  of  the  volatile  products, 
the  want  of  system,  and  the  irre- 
gularity which  attends  the  man- 
agement of  the  furnace.  Habits 
of  economy  and  attention  to  a  few 
simple  and  effective  rules  are  either 
entirely  neglected  or  not  enforced. 
It  must  appear  obvious  to  every 
observer,  that  much  has  yet  to  be 
done,  and  much  may  be  accom- 
plished, provided  the  necessary 
precautions  are  taken,  first  to  esta- 
blish, and  next  to  carry  out,  a  com- 
prehensive and  well-organized  sys- 
tem of  operations.  If  this  were 
accomplished,  and  the  management 
of  the  furnace  consigned  to  men  of 
intelligence  properly  trained  to 
their  respective  duties,  all  these 
difficulties  would  vanish,  and  the 
public  might  not  only  look  forward 
with  confidence  to  a  clear  atmo- 
sphere in  the  manufacturing  towns, 
but  the  proprietors  of  steam  en- 
gines  would  be  more  than  com- 


pensated  by  the  saving  of  fuel, 
which  an  improved  system  of  man- 
agement and  a  sounder  principle 
of  operation  would  insure.     The 
attainment  of  these  objects— -the 
prevention  of  smoke,  and  the  per- 
fect combustion  of  fuel, — are  com- 
pletely   within    the  reach   of  all 
those  who  choose  to  adopt  mea- 
sures calculated  for  the  suppression 
of  the  one  and  the  improvement  of 
the  other. 

**  On  presenting  to  the  British 
Association  an  inquiry  into  the  me- 
rits of  Mr.  C.  W.  Williams's  Argand 
Furnace  compared  with  those  of  the 
usual  construction,  it  was  found, 
from  an  average  of  a  series  of  ex- 
peruneuts,  that  the  saving  of  fuel 
(inclusive  of  the  absence  of  smoke) 
was  in  the  ratio  of  292  to  300,  or 
as  1  :  1*039,  being  at  the  rate  of  4 
per  cent,  in  favour  of  Mr.  Wil- 
Uams's  plan.  Since  then  a  con- 
siderable number  of  experiments 
have  been  made  by  Mr.  Houlds- 
worth,  Mr.  Williams,  and  others, 
which  present  some  curious  and 
interesting  phenomena  in  the  fur- 
ther development  of  this  subject." 

In  order  to  determine,  by  a  series 
of  comparative  results,  the  law  on 
which  perfect  combustion  is  found- 
ed, and  its  practical  application 
insured,  Mr.  Fairbairn  made  the 
following  points  the  subjects  of 
inquiry : 

I.  The  analysis  or  constituents 
of  coal  and  other  fuels. 

II.  The  relative  proportions  of 

the  furnace,  and  forms  of 
boilers. 

III.  The  temperature  of  the  fur- 

nace    and    surrounding 
flues. 

IV.  The  economy  of  fuel,  con- 

centration of  heat,  and 
prevention  of  smoke. 
Smoke^hoxj  the  end  of  the  boiler  on 
which  the  chimney  is  placed.  Loco- 
motives with  inside  cylinders  have 
them  placed  in  this  box,  which 
keeps  both  them  and  the  steam- 
pipes  at  a  high  temperature. 


415 


SMO 


SOUND. 


SOU 


Smoke-bojf  dooTf  the  door  in  front  of 
the  smoke-box,  by  which  access  is 
gained  to  the  cylinders  or  steam- 
pipes,  and  other  parts  phiced  in  this 
box 

Snake  wood,  a  kind  of  speckled  wood 
used  in  Demerara,  Surinam,  &c., 
for  the  bows  of  the  Indians :  the 
colour  of  the  wood  is  red  hazle, 
with  numerous  black  spots  and 
marks,  which  have  been  tortured 
into  the  resemblance  of  letters, 
or  the  scales  of  reptiles.  When 
fine,  it  is  very  beautiful,  and  is 
scarce  in  England :  chiefly  used  for 
walking-sticks,  which  are  expen- 
sive. The  pieces  that  are  from 
2  to  6  inches  in  diameter  are  said 
to  be  the  produce  of  large  trees. 

SnoWf  in  navigation,  the  largest  of 
European  two-masted  vessels.  The 
sails  and  riggiog  are  exactly  similar 
to  those  of  a  ship,  only  behind  the 
mainmast  of  a  snow  there  is  a 
small  spar  or  mast,  fixed  into  a 
block  of  wood  on  the  quarter-deck, 
which  carries  a  sail  resembling  the 
mizen  of  a  ship. 

Snyingt  in  navigation,  a  circular  plank 
edgewise,  to  work  in  the  bow 

Socte,  in  architecture,  a  flat  square 
member  under  the  bases  of  the 
pedestal  of  statues  and  vases 

Soffit^  in  architecture,  any  timber 
ceiling  formed  of  cross-beams  or 
flying  cornices,  the  square  com- 
partments or  panels  of  which  are 
enriched  virith  sculpture,  painting, 
or  gilding 

SoU  in  heraldry,  denotes  art  the  golden 
colour  in  the  arms  of  sovereign 
princes 

Solar  monthf  that  space  of  time  oc- 
cupied by  the  sun  in  going  through 
one  sign  or  a  twelfth  part  of  the 
zodiac 

Solar  System,  in  astronomy,  the 
order  or  supposed  disposition  of 
the  celestial  bodies  which  move 
round  the  sun  as  the  cehtre  of  their 
motion 

Solar  year,  that  space  of  time  in 
which  the  sun  returns  again  to  the 
same  equinoctial  or  solstitial  point, 

416  " 


which  is  about  365  days,  5  boors, 
and  50  minutes 

Soldering  is  the  process  of  uniting  the 
edges  or  surfaces  of  similar  or  dis- 
similar metals  and  alloys,  by  partial 
fusion.  In  general,  alloys  or  solders 
of  various  and  greater  degrees  of 
fusibility  than  the  metals  to  be 
joined,  are  placed  between  them, 
and  the  solder,  when  fused,  unites 
the  three  parts  into  a  solid  mass : 
less  frequently  the  surfaces  or  edges 
are  simply  melted  together  with  an 
additional  portion  of  the  same 
metal. 

Sole,  the  seat  or  bottom  of  a  mine, 
applied  to  horizontal  veins  or  lodes 

Solidity,  in  geometry,  the  quantity  of 
space  contained  or  occupied  by  a 
solid  body,  called  also  its  solid  con- 
tents, estimated  by  the  number  of 
solid  or  cubic  inches,  feet,  yards, 
&c.  which  it  contains 

Solids  are  all  bodies  that  haTe  the 
three  dimensions ;  and  among  geo- 
metricians those  that  are  terminated 
by  regular  planes  are  called  regular 
solids,  such  as  the  tetrahedron, 
hexahedron,  octahedron,  dodeca- 
hedron, and  icosahedron 

Sondelets  of  iron,  used  for  the  win- 
dows of  St.  Stephen's  chapel,  are 
fastenings  and  cross  mullions 

Sough,  an  adit  or  level  for  carrying 
off  water 

Sound  is  produced  by  a  sudden  shock 
or  impulse  given  to  the  air :  these 
impulses,  if  quickly  repeated,  can- 
not be  individually  attended  to  by 
the  ear,  and  hence  they  appear  as 
one  continued  sound,  of  which  the 
pitch  or  tone  depends  on  the  num- 
ber occurring  in  a  given  time ;  and 
all  continued  sound  is  but  a  repe- 
tition of  impulses. 

The  motion  of  sound  through  the 
air  is  at  the  rate  of  about  1125 
feet  per  second  at  the  temperature 
of  62®.  At  the  freeang  tempera- 
ture, when  the  air  is  denser,  it  is 
only  1089f  feet  per  second.  The 
method  of  detemdning  this  Telocity 
is  to  watch  the  time  that  elapses 
between  the  flash  and  the  report  of 


sou 


SOUND. 


a  gun  fired  at  the  distance  of 
several  miles  from  the  obserrer. 
As  light  travels  at  the  rate  of 
nearly  200,000  miles  per  second, 
its  passage  occupies  a  portion  of 
time  too  small  to  be  measured  in 
any  terrestrial  distance.  It  may, 
therefore,  be  supposed  to  be  seen  at 
the  distance  of  several  miles  from 
the  observer  at  the  very  instant  of 
its  production.  If,  therefore,  an 
observer  at  one  station  begin  to 
count  seconds  on  an  accurate  dial, 
the  moment  he  sees  the  flash  of  a 
gun  at  another  station,  say  ten 
miles  off,  the  number  of  seconds 
and  fractions  of  a  second  virhich 
elapse  between  seeing  the  flasffa  and 
hearing  the  report  will  give  a  di- 
visor for  the  number  of  feet  between 
the  two  stations,  and  the  quotient 
will  represent  the  velocity  of  sound 
in  feet  per  second. 

All  sounds,  whatever  their  in- 
tensity, whether  the  noise  of  a 
cannon  or  a  whisper, — ^whatever 
their  pitch,  whether  from  the  dia- 
pason organ^pipe  or  the  chirping 
of  a  cricket, — and  whatever  their 
quality,  whether  the  finest  music 
or  the  most  grating  noise, — all  tra- 
vel with  the  same  amount  of 
speed. 

When  sound  frt>m  any  source 
is  propagated  in  air,  waves  are 
formed  similar  in  character  to 
those  which  may  be  so  beautifully 
studied  when  the  wind  is  blowing 
over  a  field  of  standing  com.  Now, 
when  it  is  said  that  sound  travels 
at  the  rate  of  1125  feet  per  se- 
second,  it  is  not  meant  that  the 
particles  of  air  move  through  that 
distance  any  more  than  the  ears 
of  com  travel  from  one  end  of  the 
field  to  the  other;  it  is  only  the 
form  of  the  wave  which  thus  tra- 
vels. So  with  the  particles  of 
air:  their  individual  movement  is 
confined  within  narrow  limits ;  but 
the  effect  of  this  movement  is  pro. 
pagated  from  particle  to  particle 
^th  the  rapidity  of  1125  feet  per 
second,  which,  although  it  would 

«7 


, SOU 

be  thought  very  rapid  for  a  motion 
or  the  transfer  of  a  body,  (S 
about  ten  times  faster  than  S! 
most  violent  West  India  hurriLe  1 1 
18  y^t  very  slow  for  the  c^S 
cation  or  transfer  of  motion ;  foj  if 
we  puU  or  pnsh  one  end  of  a  solid 
rod,  or  the  liquid  fiUimr  *  ]T 
tube,  the  other  enHpleL^t^ 
je°^\**  «?e  same  instant  f  aTd  ^ 
though  this  motion  must  nS 
time,  (unless  the  body  wer^SS^ 
fectly  mcomprehensibJe,;  itiJ 
much  more  rapid  in  these  cases 
than  in  air,  which,  on  account  of 
its  great  compressibility,  is  one  of 
the  slowest  conveyers  of  sound. 
Every  one  must  have  observed  that 
vibration  can  be  diffused  through 
a  long  mass  of  metal  or  wood,  so 
as  to  be  heard  at  a  greater  distance 
than  through  an:;  but  in  this  case, 
if  the  sound  be  loud  enough  to  be 
audible  through  the  air  also,  it  will 
be  heard  twice,  first  through  the 
solid,  and  then  through  the  air. 
Iron  conveys  sound  about  17  times 
faster  than  air,  wood  from  17  to 
11  times,  and  water  4^  times  faster 
than  air. 

When  waves  of  sound  meet  any 
fixed  surface  tolerably  smooth,  they 
are  reflected  according  to  the  law 
of  equal  angles  of  incidence  and 
reflection.    In  this  way  echoes  are 
produced.     Between  two  parallel 
surfaces  a  loud  sound  is  reflected 
backwards  and  forwards,  and  seve- 
ral echoes  are  audible.    Six  may 
be  heard  between  Carlton  Terrace 
and  the  Birdcage  Walk,   in  St. 
James's  Park,  London;  fourteen 
between  the  steep  banks  of  the 
Avon  at   Clifton,   and   aa    many 
under  Maidenhead  railway  bridge. 
When    the    parallel  surfaces  are 
much  nearer  together,  ^  the  walls 
of  a  room,)  although  a  large  num- 
ber of  echoes  are  produced,  they 
follow  eafth  other  too  rapidly  to  be 
distinguished;  and  as  they  reach 
the  ear  after  equal  intervals,  they 
produce  a  musical  note,  however 
unmusical  the  original  noise  may 


sou 


SOUND. 


SOU 


have  been.  Hence  all  the  pheno- 
mena of  reverberation.  The  pitch 
of  the  note  depends  on  the  dis- 
tance between  the  two  walls  which 
cause  it,  and  may  be  calculated 
therefrom. 

A  noise  may  also  produce  a 
musical  echo  by  being  reflected 
from  a  large  number  of  equidistant 
surfaces  receding  from  the  ear,  so 
that  the  sound  reflected  from  each 
may  arrive  successively  at  equal 
intervals.  If  we  stamp  near  a 
long  row  of  palisades,  a  shrill 
ringing  will  be  heard.  A  fine  in- 
stance of  the  same  kind  is  said  to 
occur  on  the  steps  of  the  great 
pyramid.  If  the  distance  from 
edge  to  edge  of  each  step  were  2 
feet  1  inch,  the  note  produced 
would  be  the  tenor  c,  because 
each  echo  (having  to  go  and  re- 
turn) would  be  4  feet  2  inches 
later  than  the  previous  one,  which 
is  the  length  of  the  waves  of  that 
note.  But  as  the  steps  gradually 
diminish  in  size  upwards,  the  echo, 
if  produced,  and  heard  at  the  bot- 
tom, must  gradually  rise  in  pitch. 

Sir  Isaac  Newton  discovered  a 
wonderfid  coincidence  which  exists 
between  sound  and  colours,  and 
proves  mathematically  that  the 
spaces  occupied  by  the  colours  in 
the  prismatic  spectrum  correspond 
with  the  parts  of  a  musical  chord, 
when  it  is  so  divided  as  to  sound 
the  notes  of  an  octave.  So  this 
resemblance  may  now  be  consi- 
dered as  extending  further,  for  as 
in  music,  so  likewise  in  colours,  it 
will  be  found  that  harmony  con- 
sists in  distance  and  contrast,  not 
in  similitude  or  approximation. 
Two  notes  near  each  other  are 
grating  to  the  ear,  and  called  dis- 
cords :  in  like  manner,  two  colours 
very  near  each  other  are  unpleas- 
ing  to  the  sight,  and  may  be  called 
discordant. 

The  science  of  acoustics  is  lit- 
tle understood,  consequently  not 
studied  in  theory.  The  want  of 
knowledge  of  the  theory  of  sound 

Hi 


(phonics),  in  architecture,  is  a  po- 
sitive evU,  and  ofttimes  of  grievous  ' 
complaint  made  of  our  public  build- 
ings, after  the  expenditure  of  con- 1 
siderable  sums  of  money.    Sir  John  < 
Herschel  states,  that  sounds  of  all ' 
kinds  agree  in  the  foUovnng  par-  i 
ticulars:   1.  The  excitement  of  aj 
motion  in  the  sounding  body.    2.  < 
The  communication  of  this  motion  < 
to  the  air  and  other  intermedium  j 
which  is  interposed  between  the 
sounding  body  and  our  ears.  3.  The 
propagation  of  such  motion  from 
particle  to  particle  of  such  inter- 
medium in  due  succession.     4.  Its 
communication,  from  the  particles 
of  the  intermedium  adjacent  to  the 
ear,  to  the  ear  itself.  5.  Its  convey- 
ance in  the  ear,  by  a  certain  me- 
chanism, to  the  auditory   nerves. 
6.  The   excitement  of    sensation. 
The  motion  of  sound  has  been  de- 
monstrated by  Chladin  on  plates 
of  glass   and  metal,  by  strewing 
sand  on  their  surfaces,  and  obsor- 
ing  the  forms  it  assumed  when  the 
sound  ceased,  the  sound  being  ]mo- 
duced  on  the  plate  by  a  violin  bow. 
Sound  has  been  used  to  discover 
the  nature  of  disease :  by  the  ste- 
thoscope, an  instrument  aim^im.  to 
a  flute  tube,  physicians  ascertain 
the  state  of  pulmonary  disorders, 
by  applying  it  to  the  exterior  sur- 
face of  the    body    covering    the 
lungs.    In  Chladin's  theory,  it  is 
stated,  that  rooms  will  be  favour- 
able to  the  transmission  of  sound 
when  arranged  to  fiunlitate  its  na- 
tural progress, — when  its  intensity 
is  augmented  by  resonance  or  simul- 
taneous reflection,  so  that  the  re- 
action is  undistinguishable  from  the 
primitive  sound,  —  when  not   too 
lofty  or  too  vaulted, — when  there 
is  not  a  too  extensive  surface  for  the 

sound  to  strike  against  at  once 

when  the  seats  are  successively  ele- 
vated. He  observes,  that  when  the 
enclosed  space  does  not  exceed  65 
feet,  any  form  may  be  adopted  for 
a  room;  that  elliptical,  circular, 
and    semi-circular  plans  produce 


sou 


SPECIFIC  GRAVITY. 


SPE 


prolonged  reverberation ;  parabolic 
plans  and  ceilings  are  the  best  for 
distinct  hearing ;  and  that  for  con- 
cert-rooms, square  and  polygonal 
plans  shonld  have  pyramidal  ceil- 
ings* and  circular  plans  domed 
oneSi  and  the  orchestra  be  placed 
on  high,  in  the  centre,  to  produce 
the  best  effect,  and  avoid  echo. 
Mr.  Robert  Mills,  an  American  archi- 
tect, describes  the  House  of  Repre- 
sentatives of  the  United  States' 
Congress  as  the  most  elegant  le- 
gislative hall  in  the  iK'orld:  the 
plan  is  a  semicircle  of  96  feet  chord, 
elongated  in  its  diameter  line  by  a 
paraUelogram  72  feet  long  by  25 
feet  wide :  the  height  to  the  enta- 
blature-blocking is  35  feet,  and  to 
apex  of  the  domed  ceiling  57  feet, 
which  is  pierced  by  a  circular 
aperture,  crowned  by  a  lantern. 
Besides  additional  seats  and  other 
improvements,  a  more  important 
object  has  been  accomplished, — 
namely,  rendering  the  hall  a  better 
speaking  and  hearing  room,  in 
which  it  was  before  seriously  de- 
ficient. The  voice  is  now  com- 
paratively distmct,  and  the  ear  not 
sensible,  except  in  a  few  particular 
points,  of  any  reverberation  of  the 
sound :  where  the  voice  before  was 
confused  and  indistinctly  heard,  it 
is  now  full  and  clear. 

Sounding-board^  a  canopy  over  a  pul- 
pit, intended  to  difftise  the  sound 
of  a  preacher's  voice  through  the 
church 

JS^MiUmg,  in  mining,  breaking  up  into 
smaU  pieces  for  the  sake  of  easily 
separating  the  ore  from  the  rock, 
after  which  it  undergoes  the  pro- 
cess of  lobbing 

^tMin,  or  chord  of  an  arch,  ^  ima- 
ginary line  extending  between  its 
springing  on  each  side 

SpandrUj  an  irregular  triangular 
space  formed  between  the  outer 
curve  or  extrados  of  an  arch;  a 
horizontal  line  from  its  apex  and  a 
perpendicular  line  fh>m  its  spring- 
ing; also  a  space  on  a  wall  between 
the  outer  mouldings  of  the  two 


arches,  and  a  horizontal  line  or 
string-course  above  them ;  like- 
wise, between  similar  mouldings 
and  the  line  of  another  arch  rising 
above  and  enclosing  the  two 

Spandril  hracketmgy  a  cradling  of 
brackets  fixed  between  one  or 
more  curves,  each  in  a  vertical 
plane,  and  in  the  circumference  of 
a  circle  whose  plane  is  horizontal 

Spanish  Black  is  a  soft  black,  pre- 
pared by  burning  cork  in  the  man- 
ner of  Frankfort  and  ivory  blacks ; 
and  it  differs  not  essentially  from 
the  former,  except  in  being  of  a 
lighter  and  softer  texture.  It  is 
subject  to  the  variation  of  the 
charred  blacks,  and  eligible  for  the 
same  uses. 

Spanish  Red  is  an  ochre  differing  little 
from  Venetian  red 

Spanshaclef  alarge  bolt  driven  through 
the  forecastle  and  forelocked  un- 
der the  forecastle-beam,  and  under 
and  upon  the  upper  deck-beam ; 
on  the  forecastle  it  has  a  large 
square  ring/  for  the  end  of  the 
davit  to  fix  in 

Spar,  a  piece  of  timber  employed  as 
a  common  rafter  in  a  roof 

Specific  Gratify  oi  a  body  is  the 
relation  of  its  weight,  compared 
with  the  weight  of  some  other 
body  of  the  same  magnitude.  A 
body  inmiersed  in  a  fluid  will  sink 
if  its'  specific  gravity  be  greater 
than  that  of  the  fluid ;  but  if  it  be 
less,  the  body  will  rise  to  the  top, 
and  will  be  only  partly  uncovered. 
If  the  specific  gravity  of  the  body 
and  fluid  are  equal,  then  the  body 
will  remain  at  rest  in  any  part  of 
the  fluid.  If  the  body  be  heavier 
than  the  fluid,  it  loses  as  much  of 
its  weight  when  immersed  as  is 
equal  in  wieight  to  a  quantity  of 
the  fluid  of  the  same  bulk.  If  the 
specifi^c  gravity  of  the  fluid  be 
greater  than  that  pf  the  body,  then 
the  quantity  of  the  fluid  displaced 
by  the  part  immersed  is  equal 
in  weight  to  the  weight  of  the 
whole  body.  Therefore  the  spe- 
cific gravity  of  the  fluid  is  to  that 


419 


SPB 


SPINNING-JENNY. 


SPI 


of  the  body  as  the  whole  mag;iii- 
tude  of  the  body  is  to  the  part 
immersed.  The  specific  gravities 
of  equal  solids  are  as  their  parts 
immersed  in  the  same  fluid.  The 
specific  gravities  of  fluids  are  as 
the  weights  lost  by  the  same  im- 
mersed body. 

To  form  a  Table  of  the  specific 
weights  of  yarions  substanoeSt  it  is 
necessary  to  select  one  as  the  stan- 
dard of  comparison :  in  practice, 
pure  water  is  always  chosen  as  the 
starting-point  for  solids  and  liquids, 
and  pure  atmospheric  air  for  gases, 
the  number  1  (I'OOO)  expressing 
their  specific  gravities.  The  form- 
ation  of  two  series  is  considered  to 
be  more  convenient  than  the  com- 
parison of  all  bodies  by  one  stand- 
ard, on  account  of  the  complexity 
of  the  numbers  which  would  result. 


Solids  and  Liquids. 

Water 

.    1000 

Platinum 

.  21-5 

Gold 

.  19-5 

Mercury 

.  13-5 

Lead 

.  11-45 

Silver 

.  10-5 

Copper    . 

.    8-96 

Iron,  cast 

.    7-2 

Iron,  rod 

.    7-7 

Steel 

.    7-8 

Diamond 

.    3-5 

Rock  Crystal    . 

.    2-6 

Window-glass  . 

.     2-52 

Wax 

.    0-964 

Sulphuric  add 

.     1-84 

Oil  of  Turpentine      . 

.    0*865 

Spirit  of  Wine  (strong) 

.    083 

Ether 

.    0-72 

Gates, 

Atmospheric  air 

.     1-000 

Oxygen    . 

.     M06 

Hydrogen 

.    0069 

Nitrogen 

.    0-972 

Carbonic  acid  . 

.     1-524 

Carbonic  oxide 

.    0-967 

Pit  gas     . 

,    0-558 

Light  gas 

.    0-985 

(For  the  spedflc  gravitiei 

1  of  some 

other  substances,  see  Data 

• 

,&c.) 

Spend,  in  mining,  to  break  ground,  to 
work  a  way 

Spere,  the  screen  across  the'  lower 
end  of  the  hall,  in  domestic  build- 
ings of  the  middle  ages 

^l>erver,  the  wooden  £nme  at  the  top 
of  a  bed  or  canopy 

Sphere,  in  geometry,  a  globe*  a  solid 
contained  under  one  onifonn  sur- 
£bm»,  every  point  of  whidi  is  equally 
distant  from  a  point  within,  called 
the  centre  of  the  sphere,  and  may 
be  conceived  to  be  generated  by 
the  revolution  of  a  semicircle  about 
its  diameter,  which  is  fixed,  and  is 
called  the  axis  of  the  sphere 

l^herical  bracketing,  the  forming  of 
brackets  to  support  lath-and-plaster 
work,  so  that  the  sur&oe  of  the 
plaster  shall  form  the  sar£aoe  of  a 
sphere 

Spheroid,  a  solid  body  resembling  a 
sphere,  supposed  to  be  generated 
by  the  revolution  of  any  oval  about 
an  axis 

Spheroidal  braekettng,  the  bracketlDg 
prepared  for  a  plaster  ceiling  whose 
surface  is  to  form  that  of  a  sphe- 
roid 

Spice-pUUe.  At  the  condnsion  of 
Queen  Ann  fioleyn's  coronation 
dinner,  she  took  w^ers  and  ipocras. 
"  The  table  was  then  takoi  up,  and 
the  Earl  of  Rutland  bronght  np  the 
sumap,  and  laid  it  at  the  boofd's 
end,  and  the  Queen  washed ;  she 
arose  and  stoode  in  the  middest  of 
the  palace  hall:  to  whom  the  Eari 
of  Sussex,  in  a  goodlie  spioe-plate, 
brought  a  void  of  spice  and  com- 
fits." 

Spieeries  andpepper^hoxea  were  made 
very  laige  in  the  Tudor  times,  and 
placed  on  the  high  table :  their 
shape  vTas  that  of  a  tower,  castel- 
lated and  triple  -  turreted,  into 
which  all  kinds  of  spices  were 
placed,  of  which  our  ancestois 
were  inordinately  fond 

Spinnmff'Jenny,  in  mechanics,  a  ma-  ^ 
chine  used  in  the  cotton  mannfac- 
tories  to  turn  a  great  number  of 
spindles,  by  means  of  bands  fiom 
a  horizontal  wheel 


420 


BND  or  FAKT  III. 


SPI 


SPRING. 


mi^-m^^^mJO. 


St*H 


Spinning'Wheel,  the  wheel  formerly 
employed  ia  the  spinning  of  mate- 
rial for  textile  fabrics :  it  consisted 
of  a  wheel  which  gave  motion  to  a 
spindlei  on  which  the  thread  spun 
by  the  fingers  was  wound 
Spira  (Latin),  the  base  of  a  column : 
this  member  did  not  exist  in  the 
Doric  order  of  architecture,  but 
was  always  present  in  the  Ionic 
and  Corinthian;   and  besides  the 
bases  properly  belonging  to  those 
orders,  there  was  one  called  the 
Attic,  which  may  be  regarded  as  a 
variety  of  the  Ionic 
Spiral,  in  geometry,  a  curve-line  of 
the  circular  kind,  which  in  its  pro- 
gress always  recedes  more  and  more 
from  its  centre.    In  architecture,  a 
curve  that  ascends  winding  about 
a  cone  or  spire,  so  that  all  its 
points  continually  approach  its  axis. 
S^re,  in  geometry,  a  line  drawn  pro- 
gressively round  the   same  axis, 
with  a  Stance  between  each  cir- 
cle ;  a  curve-line ;  any  thing  con- 
torted or  wreathed ;  a  curl,  a  twist, 
a  wreath.    In  architecture,  it  de- 
notes any  thing  growing  up  taper ; 
a  round  pyramid,  a  steeple. 
Spirit  of  tftne,  or  dlcoholy  is  weaker 
and    more   dilute  than    essential 
oils,  or  even  than  water,  and  is 
so  volatile  as  to  be  of  use  only 
as  a  medium  for  combining  oils 
with  resins,  &.C.,  as  a  powerful 
solvent  in  the  formation  of  spirit- 
varnishes,  and  in  some  degree  as 
an  innocent  promoter  of  drying  in 
oils  and  colours.    In  picture-clean- 
ing it  affords  also  powerful  means 
of  removing  varnishes,  &c. 
Spirit-level,  a  cylindrical  glass  tube, 
filled  with  spirit  of  wine,  except  a 
small  bubble  of  air.    In  whatever 
position  the  tube  may  be  placed, 
the  bubble  of  air  will  always  tend 
to  the  highest  part  of  it ;  but  when 
placed  in  a  perfectly  horizontal  po- 
sition,  the  bubble  will  remain  sta- 
tionary at  the  centre  of  the  tube. 
Spirketing,  the  strake  wrought  on  the 
ends  of  the  beams  of  a  ship ;  where 
there  are  ports,  it  is  the  two  strakes 


worked  up  to  the  port-cdbt^^ 
which  case  the  middle  '*^*'the 
planks  should  not  be  redubefl^  Sin- 
less it  occasions  the  huts  to  %iii4ess 
than  6  inches  *.  >i^^ 

i^tYa/,  a  hospital  '.u  <tt 

J^Uuhera,  screws  or  guard8'-t)lMed 
over  locomotive.enginewhe<!ik(uku- 
ally  faced  with  brass),  to'|ltievent 
any  person  on  the  engin&^ijomfng 
in  contact  with  the  wheeU^'itod 
also  to  protect  the  machinery  fk)m 

.  any  wet  or  dirt  thrown  up'hy^th^ 
wheels  nii-i<i< 

Splay,  the  slanting  or  bevelled^esp&n- 
sion  groin,  in  Gothic  and  Ddihe^tic 
architecture,  to  doors,  wiiuHirks, 
and  openings  in  walls,  &c.*'  ''-'=' 

^lit'pins  and  cotters,  round  aiiid'€at 
pins,  with  a  head  at  one  cNidi'^nd 
split  at  the  other  end.  Th^'iu'e 
used  through  the  ends  of  btiltsy  to 
keep  them  from  getting  -  out'^of 
their  place,  the  split  end  being 
opened  like  the  letter  ><,  to^k^ep 
the  pin  or  cotter  from  falling  o«n;. 

Spoons.  In  eating,  spoons  seem' to 
have  been  almost  the  only 'aid' to 
the  fingers  at  a  very  early  period  of 
our  history.  "  Knives  (anieieiit^  as 
they  are)  were  first  made  in«'Efig- 
land  in  1563,  by  Thomas  Matheks, 
on  Fleet  Bridge,  London,"  ahdwere 
therefore  only  obtainable;  i>ii'^ny 
considerable  number,  before  "that 
time,  by  the  upper  classes- (yf  so- 
ciety. Horn  and  wood  wei^e^lhe 
materials  of  which  spooiW^  W^re 
made  down  to  Elizabeth's'  rclign, 
when  pewter  became  commenj^ftnd 
was  much  improved.  < ''  '^^  * 

Spray,  in  navigation,  the  sprihkHng 
of  the  sea  driven  from  the  t(ip>  (if  a 
high  wave  in  stormy  weathfet  *•' 

Spring,  in  mechanics,  an  elastie*betdy, 
which,  when  distorted  oi*  <90m- 
pressed,  has  the  power  of  resioktng 
itself;  any  active  power  by  ^ch 
motion  is  produced  or  propa^;aited 

Spring,  in  navigation,  a  rope  <pasled 
out  at  one  extremity  of  a  shij9^:tnd 
attached  to  a  cable  from  the  other, 
to  bring  her  broadside  to  bear-h^on 
on  an  object  .ui  lu 


ftHR 


SPRINGS. 


SPR 


>i 


1 1 


^jf^nf^  in  locomotive  enginesy  the 

n  (i  tlailic  steel  supporters  of  the  boiler 

.'iSi^A^frame  upon  the  axles,  named 

"  sflet  the  particular  parts  to  which 

they    apply  ;   as  leading  -  springs 

for  the  leacUng-axle,  driving-springs 

inf^he  driving-axle,  trailing-springs 

fo9  ihe  trailing-axle,  tender-springs, 

flj»gfspnngs,buffer-8prings,  piston- 

4piSDgs,  vdve-springs,  &c.,  all  pro- 

!po^:iifl«ied  to  the  particular  duty 

111  tfae^Tihave  to  perform 

^nKt^tvif— Water-springs,  top-springs, 

springs  of  the  deep,  &c.    In  con- 

-.liemplating  the  origin  and  utility  of 

. . .  nmitap-springs,  as  dispersed  upon  the 

,'.  liaee  ofthe  earth,  for  the  use  of  man 

and  beast,  and  as  far  deep  in  the 

iifeHrtib  as  the  miner's  art  has  led,— 

t>i.vei>^d  much    both    to    inform 

:  1  and  llAmuse  those  who  have  not 

0 ;  madfi.this  subject  their  study.    All 

1 1  spodngs  take  tiieir  source  from  the 

. :  ie^,  'lakes,  and  rivers :  by  the  heat 

<!  IrOm.  that  great  luminary  of  our 

.«arth».the  sun,  they  are  evaporated 

tiiintftthe  upper  regions,  and  there 

V :  ratcfiad,  forming  douds  filled  with 

>  tBih j  irhich,  by  attraction  and  dif- 

•  t.  ftrenibcause8,is  plentifully  showered 

•  nifton.the  earth.  It  has  been  urged 
,i^:acfene,  that  it  is  impossible  for 
I  r  rain  I  to  supply  the  copious  springs 
^  ijthsi  arise  in  stony  countries,  where 
i..;(hefeL>is  little  appearance  of  a  re- 

.  xetving  soil,  and  that  rocky  ground 

.,is  impervious  to  them.  But  it  must 

>i  fac  admitted,  that  if  rocks  make  a 

,  .>  ^^ischarge  of  water,  they  are  also 

i^ I ^ sizable  of  receiving  it;  and  that 

rocky  countries  are  generally  as  well 

.  Hilled  with  springs  as  others,  is 

«:  woU  known  to  all  travellers.    One 

of  tiie  most  stony  countries   in 

'i£Urope  Ib  Norway,  where  there  is 
...  XD  abundant  supply  of  pure  water. 
>,  liihaa  also  been  stated  that  those 
1  .<pi«c^  where  it  never  rains,  both 

jiiii.A^&ica  and  some  parts  of  Ame- 
b'tdeil,  are  yet  well  supplied  with 
hMprin^y  and  at  times  have  flooded 
,  i^xfixezB.  Whence  come  their  springs  ? 
iioPiefiNile,  Niger,  &c.,  are  rivers 
of  magnitude,and  drain  the  greatest  | 
_ 


part  of  Africa.  They  are  seldom 
replenished  with  rain;  but  they 
receive  their  immense  floods  from 
the  extensive  mountainous  country 
lying  above  and  behind  them, 
where  they  have  all  kinds  of 
weather ;  and  some  of  the  hills  are 
annually  covered  with  snow,  as 
well  as  those  districts  in  America 
where  it  seldom  rains:  but  the 
dews  are  very  prolific,  so  much  so, 
that  on  walking  out  in  the  evening 
or  early  in  the  morning,  amongst 
the  herbage,  it  is  nearly  the  same  as 
in  this  country  after  a  shower  of 
rain.  Hence  it  may  be  fairly 
presumed,  that  the  springs  iA  those 
countries  are  fed  by  the  excessive 
dews,  similar  to  rain  in  other  parts 
of  the  world,  drawn  from  seas, 
lakes,  and  rivers,  from  the  exhala- 
tions by  the  sun  daring  the  heat 
of  the  day.  In  those  tropical  cli- 
mates, night  and  day  are  nearly 
equally  chvided.  Nature  is  thus 
perfect  in  all  her  works,  by  allow. 
ing  a  sufficient  period  for  the  de- 
scent of  dews  to  supply  the  place 
of  rain. 

It  has  be«i  likevdse  assayed, 
that  the  principal  springs  come 
from  the  sea,  and  ascend  their 
different  chasms  in  the  lower  parts 
of  the  earth  connected  with  it; 
that  the  water  is  then  forced  in, 
divested  of  its  saltness,  and  made 
fresh  by  percolation  through  the 
sand  or  silt  in  those  chasms.  It 
then  beomes  the  lighter  fluid.  The 
superior  gravity  of  the  salt  then 
causes  it  to  rise  to  the  height  of 
the  highest  hills.  This  hypothesis 
has  proved  to  be  unsound.  The 
water  of  salt-springs,  from  which 
so  large  a  portion  of  salt  is  made, 
by  evaporation,  pumped  up  from 
the  coal-pits  at  Butley,  in  Durham, 
and  at  Newcastle,  is  not  sea-water, 
but  is  of  a  redder  colour,  and  con- 
tains a  far  larger  portion  of  natron. 
But  what  is  still  a  greater  proof 
that  those  salt-springs  have  no 
connection  vrith  the  sea,  is,  that  in 
the  middle  of  the  river  Wear,  be- 


SPR 


SQUARE. 


SQU 


tween  Durham  and  Bishop's  Atick- 
land,  during  the  droughty  months 
of  summer,  ^hen  the  waters  are 
low,  from  a  rock  bottom  arises  one 
of  the  finest  salt-water  springs 
known,  many  degrees  Salter  than 
that  of  the  sea,  surrounded  by 
copious  streams  of  fresh -water; 
and  this  place  is  between  200  and 
300  feet  above  the  level  of  the  sea. 
What  syphon-Uke  power  could  force 
it  to  this  altitude,  so  far  within  the 
land,  from  that  fieincied  source? 
All  these  kind  of  springs  receive 
their  saltness  from  passing  through 
beds  or  mines  of  salt,  such  as  those 
at  the  Wicke,  in  Cheshire,  &c.,  or 
some  matter  yet  unknown,  of  a  less 
dense  body,  that  will  more  easily 
communicate  its  Salter  particles  to 
the  water  running  through  it. 
"What  say  the  inspired  writers  ? — 
"  There  is  a  multitude  of  waters  in 
the  heavens  ;**  and  "  He  causes  the 
vapours  to  ascend  from  the  ends  of 
the  earth :"  **  He  makes  the  rain." 
That  is,  from  its  seas,  its  lakes, 
and  rivers,  by  natural  exhalations, 
the  clouds  are  replenished.  "  He 
bindeth  up  the  waters  in  his  thick 
clouds ;  and  the  cloud  is  not  rent 
under  them."  **  Who  hath  divided  a 
watercourse  for  the  overflowing  of 
its  waters,  to  cause  it  to  rain  on 
the  earth?*'  The  vapours  which 
arise  from  the  sea  are  much  more 
than  sufficient  to  supply  both 
the  surface  of  the  earth  and  the 
rivers  with  water;  whilst  the 
mountains,  by  their  particular 
structure  and  formation,  attract, 
and,  as  it  were,  arrest  the  vapours 
and  the  rain  that  fluctuate  about 
in  the  atmosphere ;  and  having 
collected  them  in  their  reservoirs, 
dismiss  them  again  through  their 
sides,  either  in  perpetual  or  in- 
termitting currents. 
Spring-babmcey  in  locomotive  engines, 
a  spiral  spring  weighing  balance, 
with  an  index  and  pointer.  This 
is  attached  to  the  end  of  the  lever, 
by  which  the  pressure  upon  the 
safety-valve  is  adjusted. 

423 


Spring^hooks,  in  locomotive  engines, 
the  hooks  fixing  the  driving  wheel 
spring  to  the  frame.  A  screw  on 
the  end  of  the  hook  regulates  the 
weight  on  the  driving  wheels. 

Sprvng-pvMj  in   locomotive  englnea, 
iron  rods  fitted  between  the  sprinw 
and  the  axle-boxes,  to  sustain  and 
regulate  the  pressure  on  the  axles 

Springing^  the  bottom  stone   of  an 
arch  which  lies  upon  the  impost 

Sprit,  in  navigation,  a  smal]  hoom  or 
pole  which  crosses  the  stdl  of  a 
vessel  diagonally  from  the  mast  to 
the  hindermost  comer  of  the  sail, 
to  elevate  and  extend  it 

SpriUail,  in  navigation,  the  saH  that 
belongs  to  the  bowsprit 

Sprung^  in  navigation.    When  a  top-  | 
mast  is  broken  or  cracked  near  the 
cap,  it  is  said  to  be  sprung. 

Spurs,  pieces  of  timber  fixed  on  the 
bulgeways,  and  the  upper  end 
bolted  to  the  ship's  side  above 
water,  for  security  to  the  bulge, 
ways 

Square,  in  geometry,  a  quadrilateral 
figure  with  right  angles  and  equal 
sides.  In  architecture,  an  area  of 
four  sides,  vrith  houses  on  each 
side. 

Square-rigged,  in  navigation,  an  epi- 
thet applied  to  a  ship  that  has  long 
yards  at  right  angles  with  the 
length  of  the  deck,  in  contradis- 
tinction to  sails  extended  obliquely 
by  stays  or  lateen  yards 

Square  saib  are  such  as  are  extended 
by  a  yard,  distinguished  from  others 
extended  by  booms,  stays,  lateens, 
and  gaffs 

Square  tucJt,  when  the  planks  of  the 
bottom  are  not  worked  round  to 
the  vring  transom,  but  end  at  the 
fashion-piece 

Squaring  the  circle,  in  mathematics, 
is  attempting  to  make  a  square  that 
shall  be  equal  to  a  given  circle 

Squinch,  a  term  applied  to  small  arches 
or  projecting  courses  of  stone  form- 
ed across  the  angles  of  towers 

Squint,  an  opening  through  the  wall 
of  a  Roman  Catholic  church,  in  an 
oblique  direction,  for  the  purpose 


STA 


STAIRCASES. 


STA 


of  enabling  persons  in  the  transept 
or  aisle  to  see  the  elevation  of  the 
Host  at  the  high  altar 

Stadiumf  a  Roman  measure  of  length, 
nearly  equivalent  to  our  furlong. 
The  term  was  also  applied  to  abuild- 
ing,  or  an  enclosed  area,  in  which 
gymnastic  and  athletic  exercises, 
chariot  -  racing,  and  foot-racing, 
wrestling,  and  other  public  games, 
were  exhibited.  The  stadium  was 
divided  into  distances  for  the  racers. 
Also  a  Greek  structure,  of  an 
oblong  area,  terminated  at  one  end 
by  a  straight  line,  at  the  other  by 
a  semicircle,  having  the  breadth  of 
the  stadium  for  its  base.  Around 
this  area  were  ranges  of  seats  rising 
one  above  another,  erected  for  the 
purpose  of  witnessing  the  public 
sports  at  Olympia  and  other  places. 

Staircases.  It  was  in  the  reign  of 
Elizabeth  that  staircases  first  be- 
came features  in  English  houses. 
Hand-rails  and  balustrades,  unlike 
the  rickety  contrivances  of  modem 
days,  were  of  gigantic  proportions, 
and  preseqted  at  once  a  bold,  pic- 
turesque, and  secure  appearance; 
yet  so  variously  and  fancifully  de- 
corated, that  their  effect  was  al- 
ways pleasing  and  free  from  clum- 
siness. In  the  middle  of  Yerulam 
House  was  a  delicate  staircase  of 
wood,  which  was  curiously  carved ; 
and  on  the  posts  of  every  in- 
terstice was  fixed  some  figure, 
as  a  grave  divine  with  his  book  and 
spectacles,  a  mendicant  friar,  &c. 
In  two  of  the  principal  chambers 
of  Wressil  Castle  are  small  beautiful 
staircases,  with  octagon  screens, 
embattled  at  the  top,  and  covered 
with  very  bold  sculpture,  contain- 
ing double  flights  of  stairs,  winding 
round  each  other,  after  the  design 
of  Palladio.  The  east  stairs  at 
Wimbledon  House  lead  from  the 
marble  parlour  to  the  great  gallery 
and  the  dining-room,  and  are  richly 
adorned  with  wainscot  of  oak 
round  the  outsides  thereof,  all  well 
gilt  with  fillets  and  stars  of  gold. 
The  steps  of  these  stairs  were  in 

424 


number  33,  and  6  feet  6  inches 
long,  adorned  with  5 -foot  paces, 
all  varnished  black  and  white,  and 
chequer-work;  the  highest  of  which 
foot-pace  is  a  very  large  one,  and 
benched  with  a  wainscot  ben<Ui,  all 
garnished  with  gold. 

Staircases,  in  ordinary  modem 
practice,  should  be  light,  spa- 
cious, and  easy,  seeming  to  invite 
people  to  ascend.  Principal  stair- 
cases should  not  be  narro^rer  than 
4  feet,  so  that  if  two  persons  meet 
thereon,  they  may  pass  each  other 
with  convenience;  but  they  may 
be  extended  in  breadth  to  10  or 
12  feet,  according  to  the  import- 
ance of  the  building.  The  steps 
should  never  exceed  6  inches  in 
height,  nor  be  less  than  4  inches ; 
but  this  latter  height  is  only  allow- 
able in  very  wide  staircases.  The 
breadth,  or  the  flat  horizontal  part, 
which  is  called  the  tread  of  the 
step,  should  not  be  less  than  a 
foot,  nor  exceed  15  inches. 

Stakes,  in  ship  -  building,  are  the 
regiilar  ranges  of  planks  on  the 
bottom  and  the  sides  of  the  ship, 
reaching  from  the  stem  to  the 
stern 

StaHf  a  place  occupied  by  a  monk, 
canon,  dean,  or  prebendary,  in  the 
choir  of  a  church ;  sometimes  ap- 
plied also  to  the  sedilia  or  pres- 
byteries for  the  officiating  ministers 
in  the  wall  of  a  chancel 

Stamps,  machinery  for  crushing  ores 

Stanchion,  in  ship-building,  a  small 
pillar  of  wood  or  iron,  used  to 
prop  and  support  the  decks,  awn- 
ing, &c. 

Stanchion,  the  upright  iron  bar  be- 
tween the  muUions  of  a  window, 
screen,  &c.  \ 

Standards,  timbers  in  the  form  of 
knees,  with  one  arm  on  the  deck, 
and  the  other  fayed  to  a  ship's  side  i 

Stantients,  the  upright  pieces  in  a  j 
bulk-head,  breast-work,  &c.  of  a 
ship 

Starboard,  in  navigation,  the  right* 
hand  side  of  a  ship,  looking  for- ' 
^ard,  as  larboard  is  the  left-hand    i 


STA 


STATIONS. 


STA 


StarUnffSj  in  architecture,  are  large 
piles  placed  on  the  outside  of  the 
foundation  of  the  piers  of  bridges, 
to  break  the  force  of  the  water  and 
protect  the  stone-work 
Statiet,  the  science  which  considers 
the  weight  of  bodies,  or  the  mo- 
tion of  bodies  arising  from  graTity 
Stations^  a  generic  term  appHed  to 
fixed  points  or  places,  of  which  a 
series  is  included  in  any  extended 
works  or  arrangements.    Thus  we 
have  Post-office  Stations,  Telegraph 
Station8,Police  Stations,Fire-engine 
Stations,  and  Railway  Stations. 

As  applied  to  railways,  the  term 
station  is    a  very  comprehensive 
one,    comprising    a  multitude  of 
buildings  and  apparatus  of  an  ex- 
tended and  costly  character.    Ter- 
minal stations    of  long   lines  of 
railway  usually  cover  several  acres 
of  ground,  and  include  buildings 
for  the  assembling   of  the  pas- 
sengers, and  for  classifying  them 
in  separate  compartments,  accord- 
ing to  the  class  of  carrii^e  they 
intend  to  occupy;  extended  plat- 
forms, conveniently  arranged  for 
the  arrival  and  departure  of  the 
trains,  and  well  protected  from  the 
weather,  and   lighted   by   night. 
The  level  of  these  platforms  is 
arranged    so   that   persons  walk 
directly  into  the  carriages,  without 
ascent  or  descent,  and  their  length 
is  sufficient  to  serve  many  carriages, 
or  two  or  more  entire  trains  at 
one  and  the  same  time.    A  sepa- 
rate department  of  the  station  is 
usually  allotted  to  the  receipt,  ar- 
rangement, and  distribution  of  par- 
cels and  goods  of  all  kinds,  from 
bulky  bales  and  ponderous  hogs- 
heads down  to  a  packet  of  such 
insignificant  dimensions  thlEit  it  may 
hold  no  more  than  a  half-ounce 
letter.    The  goods'  warehouses  be- 
longing to  this  department  are  of 
great  size,  and  fully  furnished  with 
cranes  and  moving  and  weighing 
gear  of  all  requisite  powers  and 
dimensions,  fitted  to  load  and  un- 
load the  goods^waggons  belonging 

425 


to  the  line,  and  all  ordinary  road 
vehicles.     Besides  these  purposes, 
the  terminal  and  first-class  stations 
often  include  a  complete  engineer- 
ing establishment  of  a  practical 
character,  in  which  the  locomotive 
engines,    carriages,    trucks,  wag- 
gons, &c.,  are  repaired  and  built, 
and  including  foundry,  smithies, 
pattern-turning,   fitting,   erecting, 
and  repairing    shops ;   the   latter 
being  provided  with  rails  below  for 
running  the  engines  into  the  build- 
ing, and  travelling  cranes  above 
for  lifting  them  entire  when  needed, 
or  aiding  in  their  dissection  with 
all  the  rapidity  and  delicacy  of 
movement  which  commonly  belong 
only  to  operations  upon  far  smaller 
and  easier  handled  subjects.    The 
station  also  embraces  ample  build- 
ings or  engine-houses  in  wliich  the 
locomotive  engines  are  ranged  like 
so  many  post-horses  in  a  road-side 
stable,  ready  for  immediate  action, 
and  in  which  the  raking  out  of 
fires  and  the  cleaning  and  adjust- 
ment are  daily  performed.    Com- 
plete arrangements  are  alsoincluded 
for  delivering  water  and  coke  to 
the  tenders,  and  in  some  the  neces- 
sary buildings  and  apparatus  are 
comprised  for  pumping  the  water 
from  deep  wells,  for  burning  the 
coke,  and  even  for  manufacturing 
the  gas  to  be  employed  in  the 
lighting  of  the  whole  of  the  build- 
ings   and    shops.      Board-rooms, 
clerks^ rooms  and  offices,  and  re- 
sidences for  the  station-master  and 
assistants,  besides  store-rooms  of 
all    kinds,    refreshment  -  saloons, 
urinals,  water-closets,  police-rooms, 
telegraph-rooms,  lost-luggage  of- 
fice, &c.,  &c.,  are  also  among  the 
necessary  details    of   a  principal 
railway  station.    The  area  of  the 
station  is  covered  with  lines  of  rail- 
way for  the  passage  of  the  engines 
and  carriages,  and  provided  with 
turn-tables,  revolving  and  travers- 
ing, for  readily  transferring    the 
carriages  from  one  line  to  another, 
besides  switches  and  apparatus  for 


STA 


STATIONS,  RAILWAY. 


STA 


connecting  the  several  lines  at  in- 
tervals. Of  the  extent  of  some  of 
these  works  at  one  of  the  metro- 
politan stations,  that  at  Camden 
Town,  on  the  Une  of  the  North 
Western  Railway,  the  following 
particulars  will  convey  some  idea : 
— This  station,  which  is  chiefly  for 
goods  only,  covers  an  area  of  30 
acres,  and  has  a  length  of  doable 
line  of  2500  feet  for  the  goods' 
waggons  only,  and  entirely  clear 
of  the  main  line.  The  length  of 
single  line  of  railway,  exclusive  of 
the  main  lines,  exceeds  12  miles. 
There  are  112  sets  of  points  for 
turning  carriages  from  one  line  to 
another,  196  turn-plates,  and  110 
cranes,  varying  in  power  from  H 
to  20  tons.  The  area  covered  with 
goods'  sheds  exceeds  135,000  su- 
perficial  feet,  and  that  of  the  plat- 
form  is  30,000  feet.  The  circular 
engine-house  is  160  feet  in  diame- 
ter, and  will  contain  24  engines  and 
tenders ;  the  central  turn-table 
within  it  is  41  feet  in  diameter. 
The  annual  consumption  of  gas 
exceeds  six  millions  of  cubic  feet. 

In  minor  or  intermediate  sta- 
tions, the  works  are,  of  course,  of 
smaller  magnitude,  and  are  not 
required  to  subserve  all  the  com- 
bined  purposes  of  a  principal  sta- 
tion. 

Stations  for  railways,  of  an  inex- 
pensive yet  neat  character  of  con- 
struction, are  erected  on  the  Tau- 
nus  Railway,  running  parallel  with 
and  being  in  the  vidnity  of  the 
Taunus  mountains  between  Franc- 
fort  on  the  Maine  and  Wiesbaden. 
The  line  runs  through  three  dif- 
ferent territories: — 1st,  commen- 
cing in  and  running  through  part  of 
Francfort;  2nd,  through  part  of 
the  Duchy  of  Nassau;  and  3rd, 
tUN)ogh  the  Grand  Duchy  of 
Ifessen  Darmsdadt,  for  a  short  dis- 
taince  going  through  the  fortress 
at  Castel;  and,  lastly,  entering  Nas- 
sau again.  The  total  length  is  27 
English  miles.  There  are  six  in- 
termediate  stations,    viz.  Hbehst, 

426 


Hattersheim,  Floraheim,  Hodicim, 
Castel,  and  Biebrich.     The  capi- 
tal of  the  company  and   cost  of 
the  line,  induding  purchase  of  land, 
stations,  locomotive  power,  machi- 
nery and  plant,  and   wfn-kshops, 
was  £275,000;  the  absolute  out- 
lay,  £ 263,286.  9#.  lid.     The  se- 
parate  cost  of  the  several  stations 
and  houses,  and  watch-houaesy  was 
£26,513.  lOf.  2^,f  including  the 
station-house  in  Francfort^  which 
is  a  large  stone  building,  being  a 
pavilion  with  two  wings,  and  at  the 
end  of  each  wing  is  a  small  pavi- 
lion.   Thelarge  or  middle  building 
contains,    Ist,    ground-floor,    the 
booking-clerks'  offices,  where  the 
tickets  are  given  out  and  money 
taken;  2nd,  in  first  story,  the  sitl 
ting-room    for    directors,    where 
their  meetings  are  held,  and  acting- 
director's  offices,  with   office   for 
head  cashier  and  secretary.     The 
attics  are  used  as  lumber-rooms 
and  store-rooms  for  artioles  which 
are  left  behind.    The  right  wing  is 
used  for  waiting-room    for   first, 
second,  and  third  class  passengers, 
being  very  well  decorated, — ma- 
hogany  so^,  with  horsehair  seat- 
ings,  running  round  the  walla  {  the 
windows  having  baautilul  chintz 
curtains,  and  the  roof  or  ceiling 
behig  tastefully  decomted.    At  the 
end  of  this  wing  is  a  small  paidUon 
two  stories  high;  the  ground-story 
being  used  ss  offices  and   stoire- 
rooms   for  luggsge    and   gctods' 
transpoi-t,  the  upper-story  as  dwell. 
ing  for  foremsn  snd  clerk.     The 
left  wing  is  used  as  waiting-room 
for   the   fourth-dsss   passengers, 
being  ss  large  as  the  other,  but 
quite  pUin,  the  seats  being  of  oak. 
The  pavilion  at  the  end  is  used  for  I 
steam*boat  offices,  &c.,  on  ground-  | 
floor,  and   the  upper  story  as  a 
dwelling  for  the  station's  overseer. 
The  station-houses  at  Castel  and 
Wiesbaden  are  very  similar  to  the 
above,  except  that  the  Castel  sta- 
tion-house is  built  of  wood,  and 
has  a  covered  passage,  used  only 


STA 


STEAM  ENGINE. 


in  bad  weather,  between  the  wait- 
ing^Tooms  and  carriages.  The  inter- 
mediate  stations  are  merely  large 
enough  for  the  clerks  to  live  in  the 
upper  stories,  the  under  parts  or 
ground-floor  being  used  as  waiting, 
room  and  clerk's  office.  The  pas- 
aenger-sheds  are  all  splendid  build- 
ings, being  three  in  number  upon 
the  main  line,  and  one  at  Biebrich, 
of  wood ;  but  from  their  neat  con- 
struction and  decoration  deceive 
the  eye  at  once  into  believing  they 
are  made  of  more  solid  and  sub- 
stantial materials.  The  dividends 
of  this  railway  have  produced  a 
return  varying  from  10  to  12^  per 
cent* 

Statuary,  a  carver  of  images  or  re- 
presentations of  life;  one  who 
practises  or  professes  the  art  of 
sculpture. 

StaveSf  in  joinery,  the  boards  that  are 
joined  together  laterally,  in  order 
to  form  a  hollow  cylinder,  cylin- 
droidi  cone,  or  conoid,  or  any 
frttstmm  of  these  bodies.  The 
shafts  of  columns,  in  joinery,  are 
frequently  glued  up  in  staves. 

Stapf  in  navigation,  a  strong  rope 
employed  to  support  the  mast  in  the 
fore-part :  tif  stay  a  ship,  to  manage 
the  sails  so  that  she  shall  not 
make  any  way  forward,  prepara- 
tory to  her  tacking  about 

Stayioilf  in  navigation,  a  sort  of  tri- 
angular sail  extended  on  a  stay 

StaySf  ouitidet  in  locomotive  engines, 
sling-stays  binding  the  boiler  and 
frame  together 

Stays,  insids  boiler,  in  locomotive 
steam  engines,  rods  of  iron  binding 
together  the  flat  ends  of  the  boilers. 
The  flat  side  of  the  dome  is  like- 
wise strongly  bound  together  by 
iron  rods.  Without  these  stays, 
they  could  not  resist  the  pressure 
of  the  steam  against  so  large  a 
surface. 

Stays,  inside  frame,  in  locomotive 
engines,  strong  stays  placed  below 
the  boiler,  firmly  fixed  at  one  end 
to  the  firc'^box,  and  at  the  other 
end  to  the  smoke-box :  they  sup- 


port the  inside  beatings  «t<!ilhe 
driving  axle  and  other  partiuMthe 
machinery  iloMw 

Stay-wedges,  in  locomotive  etf||itfes, 
wedges  fitted  to  the  inside  bwqlttgs 
of  the  driving  axles,  to  keepiilllBm 
in  their  proper  position  in  tlMiiUftys 

Steam,  the  vapour  of  hot  t||ilCei!^»at 
the  boiling  point  of  212  deiftMi 

Steam^hest,  in  locomotive  mfjtsi^, 
a  box  attached  to  the  cytl^i^, 
into  which  the  steam  is  a&B&Hed 
by  the  regulator:  the  sli^fiiallftve 
works  in  this  box  over  the^^ttei- 
ports,  which  open  into  it  frdiyttie 
cylinder.  \uoidi 

Steam^hest  eoeks,  in  locomoidv%^n- 
gines,  oil-cups,  placed  convlttAftlitly 
for  lubricating  the  faces  i%(4lhe 
steam-ports  and  slide-valv^  £^'"i'i 

Steam  concession.  The  steatff^lilch 
has  performed  its  duty  in^^bcr'iy- 
linder,  but  which  has  not  DSbfl^d 
before  the  slide-valve  daiW^^Ihe 
exhaust-port,  is  compressed'^%he 
advancing  piston.  This  cbfiipi^s- 
sion  begins,  according  to>ill9ilap 
and  travel  of  the  slide,  freiiP^to 
3  inches  from  the  end  of  th#^itt«9Le, 
and  is  of  considerable  amo^t/<i  It 
is,  however,  of  advantage  in*<6htek. 
ing  the  momentum  of  the-'^istftn, 
and  relieving  the  strain  on  m  Mn- 
necting  and  piston  rods  at  tbe^d 
of  each  stroke,  and  is  not  tlNIMf^re 
all  lost  power.  -)r:i 

Steam  Engine,  a  machine  for  £tl^t4l4iig 
power  from  the  expan8ioii|HlMch 
results  from  the  conversion  di-^ler 
into  vapour  or  stesm  by  iH^^M^li- 
cation  of  heat.  This  expdnstmi  is 
so  great  that  a  given  quantltfi  of 
water  becomes,  when  changed  uto 
the  form  of  steam,  enlarged  t<rilN^ut 
1728  times  its  original  hvSkf  Itnd 
this  expansion  takes  place  ^fft  a 
force  that  may  be  termed  irreMitable. 
Thus  if  water'be  enclosed  in&<^|S«(Mel, 
say  of  iron  or  any  other  stiW|i|^^tta- 
terial,  and  the  water  be  esfiiattded 
into  steam,  and  insufficient; tpice 
left  for  the  expansion,  the  ymsel 
will  be  burst  by  the  force^^'the 
steam  within.  A  steam  engiife^^n- 


427 


.■5S:i' 


9m. 


STEAM  ENGINE. 


STE 


t    7 


o.nis^  essentially  of  a  Tessel  into 

«  nrVJ^c}!  the  steam  is  admitted,  and 
nrhich  is  provided  with  a  moveable 

;>  4>s^<^<'>^7  fitting  the  interior  and 
^.^^^^^MLble  of  sliding  within  the  vessel. 
,r.X^( vessel  is  made  cylindrical,  be- 
^  ^qfjise'  this  form  gives  the  greatest 
t^sV^f^gth  and  is  the  most  readily 
^U^.with  the  moveable  disc.   The 

V  ifpHiA  is  termed  the  cylinder,  and 
'  rtiie :  ^c  the  piston.  Supposing  the 
( >  J97^^^'  to  ^  placed  upright,  and 
,  .$||e4vwith  a  dose  cover,  and  that 

^.l^hUe'the  piston  is  near  the  bottom 

,'lQf,j)b.fteam  is  admitted  to  rush  in 

through  a  pipe  below  the  piston, 

((tM-rPiston  will  be  driven  up  by  the 

{ A^MQi  aii^  ^f  when  it  reaches  the 

•  wppcr  part  of  the  cylinder,  the  steam 
from  below  is  shut  off,  and  admitted 
, '  .through  an  upper  pipe  to  press  upon 

/  ih«  !U>p  surface  of  the  piston,  it  will 
{•  ,b^  ^ofced  down  again.  Thus  a  rec- 
, ,  itiUoear  motion  up  and  down  is  pro- 
..fi^ttoedy  and  this  constitutes  what  is 

.itfi^ii  the  principle  of  the  steam 
,,,.fngi9e.    All  its  other  parts  are  for 

(the, .purpose  of  regulating  the  ad. 

,  ;iniS8ion  of  the  steam,  and  convert- 
,  i  ing  ^e  rectilinear  motion  produced 

;4A'thQ  cylinder  into  a  rotary  motion 

f,;^^  jtfie  point  where  the  power  is 

„i:((qvui^ed  to  be  applied  for  working 
cMiiaicMnery.  The  steam,  when  no 
■,  ,l94iger  required  for  that  purpose,  is 
allowed  to  escape  into  the  open  at- 
,j„]|9PSpliere,  or  conducted  in  a  pipe  to 
j^  .miQth^r  vessel,  which,  being  cooled 
,.|b^/^he  application  of  cold  water, 

,  rxMidly  condenses  the  steam,  that  is, 
i.i  Xf^^y^^^  i^  i^to  water.  If  per- 
■\, ,  n^U^  to  escape  into  the  air,  the 
„ .  f^te^^vo^  h&s  ^o  ^o^c^  itself  against  the 
^,  ,|ur^a9iure  of  the  atmo8phere,whereas 
,,  ^  GOj^ducted  into  a  condenser,  this 
n  ^Tf^  is  QO^  required.  Hence  steam 

uOfflW  pressure  will  work  what  is 
] .  tei^l?^  ^  loW'presetire  or  condensing 

,  ;^fi^fj^,whilethatalreadydescribedis 
r  fqp  distinction  calledaA^A-pre^ntre 
^..fft^n^  A  third  variety  of  steam 
I  o.6ngiA9  is  worked  by  shutting  off  the 
r^.,'St^«m«  before  it  has  driven  the  pis- 

,,]t;qn,tb6whoIelengthof  the  cylinder, 

428  " 


or  completed  the  Miroke^  as  it  is 
termed,  and  the  subsequent  ex. 
pansion  of  the  steam  completes  the 
impulse  upon  the  piston.  Engines 
thus  worked  are  disting^shed  as 
expansive  engines.  The  principal 
difference  in  the  mechanism  of  con- 
densingandexpansive  steam  engines 
is  in  the  movement  of  the  apparatus 
which  admits  and  shuts  off  the 
steam,  or  the  vaheSf  which  stct  as 
doors  within  the  pipes.  The  several 
parts  of  a  condensing  eng:ine  and  its 
appliances  are  as  follows :  Ist,  the 
boUsTt  in  which  the  steam  is  pro. 
duced  from  water  by  the  action  of 
fire  in  the  furnace  beneath;  2ndly, 
the  steam-pipe,  in  which  the  steam 
is  conveyed  to  the  engine ;  3rdly, 
the  f/eom-c^f^^fin which  the  steam 
isreceived,  and  whic£  communicates 
with  the  two  induetion^pipes  that 
lead  into  the  upper  and  lower  part 
of  the  cylinder ;  4thly,  the  ey Under 
fitted  with  the  piston,  and  having 
pipes,  called  the  eduetion-ptpes, 
through  which  the  steam  passes 
away  when  its  work  in  the  cylinder 
is  completed,  into  the  condenser; 
5thly,the  air>/nm9,which  abstracts 
the  water  formed  by  the  condensed 
steam,  sending  it  into  the  boiler, 
producing  a  partial  vacuum  within 
the  condenser,  and  thus  assisting 
the  escape  of  the  steam  from  the 
cylinder;  6thly,  the  coiideit««r  it- 
self, which  is  kept  cool  with  water 
pumped  up  by  the  cold-water  pump. 
The  piston  has  a  rod  fixed  to  it, 
which  works  through  a  steam-tight 
opening  or  stuffing-box  in  the  lid  of 
the  cyUnder,  and  this  piston-rod  is 
attached  to  one  end  of  a  beam, 
which  turns  upon  a  centre,  and  the 
other  end  of  which  works  a  eois- 
necting-rod  attached  to  a  crank,  to 
the  side  of  which  a  rotary  motion 
is  thus  imparted.  In  some  engines 
the  piston-rod  is  connected  by  links 
directly  with  the  crank,  and  these 
arehencetermedtf/trec^-oc/tdn  steam 
engines,  while  the  former  are  dis- 
tinguished as  beam-engimes*  In 
others,   again,  the  piston-rod   is 


STE 


STEAM  NAVIGATION. 


STE 


attached  to  the  crank  without  links , 
and  the  cylinder,  instead  of  heing 
fixed,  is  made  to  vibrate  or  oscillate: 
these  are  therefore  termed  vibrating 
or  oseiUatmg  engines.  Marine  en- 
gines for  propelling  vessels  on  the 
v^ater,  and  locomotive  engines  for 
propelling  trains  of  carriages  upon 
railways,  are  each  distinguished  by 
peculiarities  of  construction  and 
arrangements,  fitting  them  for  their 
especial  duties. 

Steam  exhaust -port,  in  the  locomo- 
tive engine,  the  passage  opened 
.  below  the  slide  -  valve  from  the 
cylinder  to  the  atmosphere.  It  is 
placed  between  the  two  steam- 
ports,  and  is  nearly  twice  their 
area,  the  more  freely  to  permit  the 
escape  of  the  steam.  It  is  open 
to  the  blast^pipe,  and  is  cut  off 
from  any  communication  with  the 
steam  in  the  steam-chest  by  the 
slide-valves.  The  arch  part  of  the 
slide-valve  opens  the  passage  from 
the  cylinder  into  the  central  ex- 
haust-port, where,  through  the 
blast-pipe  and  chimney,  it  escapes 
to  the  atmosphere,  and  by  this 
means  produces  the  draught  on  the 
fire. 

Steam-gauge,  a  contrivance  to  show 
the  exact  amount  of  pressure  of 
the  steam';  it  consists  of  a  syphon- 
tube  with  equal  legs,  half-filled 
with  mercury :  one  end  is  ce- 
mented into  a  pipe  which  enters 
that  part  of  the  boiler  which  con- 
tains the  steam ;  the  other  end  is 
open  to  the  atmosphere.  A  stop- 
cock is  usually  provided  between 
this  gauge  and  the  boiler,  so  that 
it  may  be  put  in  communication 
with  the  boiler  at  pleasure.  When 
the  stop-cock  is  open,  the  steam 
acting  on  the  mercury  in  one  leg 
of  the  gauge  presses  it  down,  and 
the  mercury  in  the  other  leg  rises. 
The  difference  between  the  two 
columns  is  the  height  of  mercury 
which  corresponds  to  the  excess  of 
the  pressure  of  the  steam  in  the 
boiler  above  the  pressure  of  the 
atmosphere ;  or,  in  other  words,  to 


the  effective  pressure  on  the  safety- 
valve.  If  half  a  pound  per  inch 
be  allowed  for  the  length  of  this 
column,  the  effective  pressure  of 
the  steam,  in  pounds  per  square 
inch,  is  obtained. 

Steam  Navigation,  This  is  accom- 
plished by  the  application  of  steam 
power  to  the  marine  engine,  by 
which  vessels  of  all  dimensions  are 
propelled  on  the  waters  of  the 
ocean  or  on  the  principal  rivers. 
Whether  by  means  of  the  pad- 
'  die-wheel,  or  by  the  spiral  or  helix 
screw,  the.  fluid  is  displaced  and 
the  vessel  sent  forward  at  the 
various,  speeds  consequent  upon 
the  skill  employed  in  the  making 
of  vessel  and  engine.  Much  com- 
petition and  many  controversies 
have  existed  upon  the  best  methods 
to  be  adopted.  Many  instances  of 
fiulures  have  occurred  from  the 
simple  circumstance  of  the  builder 
of  the  ship  and  the  constructor  of 
the  engine  not  acting  in  concert. 
Steam  vessels  for  river-passenger 
traffic,  when  in  trim  and  all  their 
parts  well  constructed,  average  a 
speed  of  1 5  miles  an  hour ;  in  Ame- 
rica 18  miles ;  and  sea-going  ves- 
sels average  on  their  way  12  miles : 
Cunard's  packets  from  Liverpool 
to  Halifax  and  Boston  have  done 
more.  The  West  India,  Peninsular, 
and  Oriental  Companies  have  splen- 
did vessels,  which  do  credit  to  the 
companies  for  their  enterprise, — ^to 
the  builders  for  the  construction  of 
the  craft,  andto  the  engineers  forthe 
construction  of  the  engines.  Other 
companies  exist  who  deserve  their 
proportion  of  praise.  It  is  to  Eng- 
land and  Scotland  that  the  world 
is  indebted  to  for  this  new  element 
of  civilization. 

Steam-pipes,  in  locomotive  engines, 
the  pipes  which  collect  and  con- 
vey the  steam  to  the  steam-chest : 
they  commence  inside  the  boiler. 
In  boilers  with  domes,  the  receiv- 
ing pipe  is  raised  as  high  as  possi- 
ble, and  turned  back  round  the 
edges  of  the  open  end,  to  prevent 


429 


t5 


STE 


STBAM^WHISTLS. 


STB 


any  water  which  ought  rise  so  high 
from  OYerlyiag  the  pipe.  In  boUers 
haying  no  domes,  the  steam  is  col- 
lected in  a  horiaontal  pipe  pierced 
with  numerous  small  holea.  After 
being  collected,  the  steam-pipes  are 
continued  outside  the  boiler  to  the 
steam-chest.  The  internal  dia- 
meter of  the  steam-pipe  is  usually 
rather  more  than  one-fifth  el  the 
diameter  of  the  steam  cylinders : 
the  area  of  the  passages  threiugh 
valves,  in  some  of  Watt's  beam  en- 
gines, is  nearly  one  square  inch  per 
horse  power.  This  is  in  some  cases 
too  large  for  steam-passages,  but 
rather  too  small  for  the  exhausting 
valve-passages. 

Steam-pipe  for  tender,  in  locomotives, 
a  small  pipe  attached  to  the  boiler 
by  a  cock,  for  admitting  the  spare 
steam  to  heat  the  water  in  the 
tender 

Steam^ports,  in  locomotive  engines, 
two  passages  from  the  steam- 
chest  to  the  cylinder.  The  steam 
is  admitted  to  and  from  these  pas- 
sages by  the  slide-valve  opening 
the  port  for  the  admission  of  steam 
to  the  cylinder,  and  then  by  shut- 
ing  off  this  port  from  the  steam  in 
the  steam-chest,  and,  opening  the 
same  passage  by  which  it  entered, 
it  is  conveyed  to  the  atmosphere. 

Steam-whistle^  an  apparatus  attached 
to  the  boiler  of  a  locomotive  engine 
for  the  purpose  oi  giving  warning 
of  its  approach  when  running.  The 
construction  of  the  whistle  is  shewn 
to  one- quarter  size  in  the  annexed 
engravings.  It  is  made  of  brass, 
and  the  foot,  a,  is  cast  hollow,  vdth 
a  flanch,  b,  at  the  bottom,  to  bolt 
it  on  the  fire-box :  it  has  a  co^k,  c, 
placed  in  it,  with  the  handle  jd,  and 
screw  E,  to  keep  it  tight ;  the  han- 
dle projects  out,  to  allow  firm  hold 
to  be  taken  of  it.  The  cup  f  is 
fixed  upon  the  foot  a,  by  screwing 
the  piece  e  upon  it,  and  both  are 
turned  truly  at  their  outer  edges, 
leaving  a  very  narrow  passage,  1 1, 
four  inches  diameter,  between  them 
all  round.    The  piece  o  is  hollow, 

430 


havini;  Mea.  «.  i«  \X%  sidca;«Acla 
pillar,  1^  standi  upon  its  centre,  on 
vribieh  ii  icvewed  lh«  bell,  l  i,  the 
thin  edge  v€  wble^  ia  brougbt  just 
over  the  openiiig  i»  and  baUso  iscfa 
above  it. 
Wh€»  the  coek  is  openod,  the 


■teua  enters  tbe  cup  r  through  the 

boles  H,  and  nuhei  out  at  the  nar- 
row ilit  I,  itriking  the  thin  edge  of 
the  bell,'i.,  in  a  mannet  similar  to 
the  action  in  oipm-ppet,  and  pro- 
ducing an  exctedinglr  shrilL  ud 
pierciag  aound.  Some  holeSi  u, 
are  >naile  in  the  top  itf  the  beU,  to 
allow  the  itaain  to  pau  throi^h, 
which  improves  the  lound  conai- 
derablj.  The  size  (rf  the  coacentric 
part  where  the  ateam  escapes,  and 
the  depth  of  the  bell  part,  and  their 
distance  arander,  resulate  the  tones 
of  the  whistle,  from  a  shrill  treble 
to  a  deep  bass.  The  cock  should 
be  steadily  opened,  to  adjust  the 
quantity  c^  steam,  so  as  to  produce 
the  clearest  sound.  The  tteam- 
whistle  is  very  effective,  and  its 
sound  ctus  be  heard  at  a  great  dia- 

Steel  is  composed  chiefly  of  iron  and 
carbon;  yetthese  alone  will  prodace 

but  a  poor  and  brittle  article.  Good 
steel  contains  a  variety  of  elements, 
almost  all  of  those,  in  fact,  which 
are  coo^idered  impurities  of  iron 
when  present  in  excess. 

Sieel  ia  divided  into  four  distinct 
dosses, — Damascus  steel ;  German 
steel  5  Blistered,  fa  blister  steel,  to 
which  class  shesr  steel  belongs; 
and  Cast  steeL  Tbe  first  is  made 
directly  from  the  ore,  ot  by  vfeld- 
ing  steel  rods  and  iron  ro^  toge- 
ther ;  tiie  second  from  pig  metal, 
liy  depriving  the  lAtter  nf  a  poition 
uf  its  carbon  aud  ini])uricica ;  the 
third  from  bar  iron,  by  impregnat- 
iug  it  with  carbon;  anil  the  fourth 
class,  or  cast  steel,  may  be  oiadc 
from  either  of  the  others,  by  iiielt- 
iag  it  in  a  crncible.  Still,  hiiM»cil 
steel  appears  to  lie  tha^ost,  a<l- 
vantageous,  so  far, naiiuajijs  1^1=9"- 

^iHfifl^di.flT-acJfliibm  of  nwjwv- 


^ m 

of  a  silvery  white,  \Hidc,^faii.gfay 
colour,  and  fine  and  coa^.Ii^s, 
exhibiting  regular  and  imgjdar 
figarcs.  The  excellent  qi^^^,  of 
theae  blades  is  proverbi^^^^t^ey 
unite  hardness  to  great  fi^^fuiify. 
Genuine  Damascus  steel- ii#  fW^ 


uul  ir 


fni-gin!?  Hnil  liariieiiiiig,  it  i«  Vitrwn 
Hint  ttie  steel  is  smelted,  in,a,^f)nd 
<if  Calslan  forge,  from  rcdoj^dftof 
iron,  a  red  cUy  ore  found  in  t!;(|isi- 
tion  slate.  It  ia  generally  l^^ved 
that  the  great  strength  of  thM-stpel 
Is  to  be  attributed  to  s  smaftSOT"" 
tity  of  aluminum  wliich  entitrx^ato 
its  composition,  and  whlchviftdB- 
rived  from  the  clay  of  tli&t)t^| — 
nn  opinion  which  has  th».fi(«tri'' 
its  favoiu',  that  no  material  iif  pait* 
a  greater  degree  of  tenacity  ,|o  )fi>n 
than  alumina.  Great  cxerti^ntiiive 
been  made  to  imitate  this,j)t^^in 
whicli,  of  all  nations,  th»  Ktf^ch 
have  been  the  most  s^cci^fCill. 
TLey  have  succeeded  in  iqiiti^^iig 
notauly  irregular  figures,  ,biti^b- 
t'^c)ues  and  initials,  in  ^^.,iu:)St 
beautiful  manner.  Still,  t^mgch 
ii  fnr  less  tenacious  and  li«^d,|£ui 
the  genuine  Damascus  steel.  ,^ha 
virtue  of  the  latter,  thereforet  U"i>t 
be  souglit  for  iu  the  ore  from  rebioh 

CmwM'OTrf'i'i'     ■■'hi 


Tlus8teelw'n»*lfi>ut 

woiiiff^ent 

ays,  .ejthpr  directly  fr 

OB  the  ore. 

lelal,  and  then  into 

leelmwiiifauureahv 

le  liist  me- 

iiMlji  g.;ii£rnlly  cimli- 

and  irregu. 

titftl««l  is 

„,.,  ■i;heStu^,iiveii,or\yi»lf'sqyc», 
i,#SlVB)l-»».tlifl,CWalaflfptgp,.i«.oue 

,^  the  furpacw  f  tnplojedin  tbfi  p*- 
.^nHfactiirc^nf  steel fiumurp..  bi^ali- 
.  hig8teeJ„iihe.blasti5diriWsdtppre 
I   upw  the  fuel, tJiau.vpQji  tluiupn 

.the  tiij:(tB.,i^;l«veii,,,the  .jrom  1: 
.liui.pregn^HMia.with  carlKin.,,Tl(a« 


9FS 


STEEL,  GERMAN. 


STE 


I  ^tarWis  the  case  in  the  manufacture 
^  'ii# '  irav.    In  the  hlue-oven ,  a  kind 
'''b£.'|rf|»  metal  is  frequently  made, 
>'^  yMkki  U  almost  pure  steel ;  but  it 
'^'ii'coane,  and  never,  even  after  the 
'lieilltTkfining,  makes  a  good  article. 
''km  manipulations,  the  object  of 
'^  'iHiiehUs  to  make  steel  directly  from 
~"'tbe  ore,  are  unprofitable. 
*'■  '•  Te  this  class  belongs  the  manu- 
"  fiMtM  of  wootz,  or  East  Indian 
^'  vtbdl."  This  is  certainly  a  good 
'^"itbd^'ind  is  partially  imitated  in 
'  America.     Wootz  is   smelted  di- 
'^  iwliy  from  the  ore,  which  is  the 
'^  blade  magnetic  oxide  of  iron,  in 
"Idmiilees  five  or  six  feet  high,  of 
'^^the'lbrm  of  some  foundry  cupolas. 
"'Previbusly  to  smelting,  the  ore  is 
findy funded  and  washed,  to  re- 
'-''  rbmt  vnpurities. 
'*""i71id' manufacture  of  steel  from 
f«"p|g>lnel«l  does  not  depend  so  much 
'^'  npen'^e  manipulations  in  the  forge 
"'  ak^i'tlpon  the  quality  of  the  metal. 
'\'^r\i&  ores  generally  employed  are 
'"tlweryBtallized  carbonate,  spathic 
""dfi^^  often  mixed  in  a  slight  degree 
'ifrith  hematite,  and  the  rich  red 
'"peroseides.    Magnetic  ores  do  not 
'^  ans^ex'  for  such  work,   and  are 
'  'the^efok'e  but  seldom  used.    The  | 
'"^me  maybe  said  in  relation  to  the 
*   faydrated  oxides.     Pig  metal  for 
'  Meel  manufacture  is  smelted  with 
as  little  lime  or  other  flux  as  possi- 
ble.   The  principal  flux  to  be  re- 
lied on  is  manganese ;  but  this  al- 
''  wa^s' exists  in  the  ore,  and  is  never 
''  used^  as  an    artificial   admixture, 
-though  it  is  possible  that  an  artifi- 
'  dal  flux  might  be  made  of  it.  Steel 
'^  metal'  is  in  most  cases  white.   It  is 
'  ^melted  by  rather  more  ore  than 
'  tihat' which  will  make  gray  iron; 
but  not  with  so  heavy  a  burden  as 
that  ^ich  will  make  white  iron 
contfldning  carbon  in  small  amount. 
Any '  ore  which   contains  foreign 
mattfer  in  such  large  amount  as  to 
make  the  addition  of  lime  as  a  flux 
-  neces^bry,  does  not  make  good  steel 
'  metal.    The  only  mode  of  working 
"  the  furnace  is,  of  course,  by  means 

432 


of  charcoal  and  the  employment  of 
the  cold  blast. 

The  forge  fires  employed  in  con- 
verting the  metal  into  steel  do  not 
difi^er  materially  from  those  in  which  | 
iron  is  made.  The  hearth  of  the  ' 
former  is  generally  larger  and  \ 
deeper,  and  the  blast  is  stronger 
than  that  of  the  latter.  Very  little  : 
iron  is  connected  with  it.  The  ; 
bottom  is  generally  formed  of  sand- 
stone, and  the  sides  of  braise,  or 
charcoal-dust  mixed  with  clay.  The 
practical  manipulation  at  these 
forge-fires  varies  according  to  loca- 
lity, to  the  form  of  the  furnace,  and 
the  qualifications  of  the  worlunen. 
The  main  principle  involved  may 
be  generalized  under  the  following 
proposition :  If  it  is  intended  to 
make  steel  instead  of  iron,  the 
metal  should  be  melted  before  and 
off  from  the  tuyere ;  and  it  shonld 
be  kept,  when  melted,  always  be- 
low the  blast,  and  never  brought 
above  or  into  the  blast.  By  due 
attention  to  locality,  every  thing 
else  may  be  easily  regulated.  A 
skilful  workman  will  soon  ascertain 
that  a  flat  hearth,  an  iron  lining, 
and  a  strongly  dipped  tuyere  will 
not  make  steel,  though  it  vdll  make 
iron,  and  that  a  weak  blast  will 
tend  to  produce  iron. 

The  crude  steel,  the  result  of  the 
first  operation,  is  generally  thrown, 
when  red-hot,  into  cold  water,  then 
broken  and  sorted.  The  most  sil- 
very part,  of  the  finest  grain,  is  the 
best,  fibrous  or  partially  fibrous 
bars  are  reserved  for  iron :  they 
make  a  superior  quality  of  bar  iron. 
Bluish-looking  steel  is  also  thrown 
aside,  for  it  will  become  fibrous 
iron  before  its  impurities  can  be 
removed.  The  crude  steel,  drawn 
out  into  bars  an  inch  or  an  inch 
and  a  quarter  square,  is  placed  in 
piles  composed  of  six  or  eight  pieces, 
then  welded,  and  drawn  out  into 
smaller  bars.  This  process,  called 
refining,  is  repeated  three  or  four 
times,  and  each  time  the  number 
of  bars  in  the  pile  is  increased. 


STE 


STEEL,  GERMAN. 


STE 


The  smaller  the  baxs  of  steel,  and 
the  greater  the  number  of  them 
placed  together,  the  more  perfect 
will  be  the  refined  steel.  The  piles 
are  heated  in  a  large  blacksmiths' 
fire,  by  stone  coal,  which  must  be 
sufiSciently  bituminous  to  form  an 
arch  over  the  fire.  Coal -slack, 
mixed  with  loam,  is  frequently  used 
for  this  purpose;  but  it  increases 
the  waste  of  steel.  The  hammer 
used  for  drawing  steel  should  be 
light,  weighing  no  more  than  150 
pounds,  and  ought  to  make  from 
300  to  400  strokes  per  minute. 
Great  skill  and  dexterity  are  re- 
quired to  draw  steel  bars.  It  is 
highly  important  to  perform  this 
operation  well,  as  the  quality  of  the 
steel  is,  in  some  measure,  depend- 
ent upon  the  manner  in  which  it 
has  been  hammered. 

In  those  countries  where  German 
steel  is  made,  a  remarkable  article 
is  manufactured,  which  deserves 
notice.  It  is  harder  than  the  best 
cast  steel,  but  so  brittle  that  it  can- 
not bear  any  bending  when  cold. 
This  article  is  cast  iron :  it  is  de- 
rived from  the  re-melted  steel  me- 
tal. From  200  to  250  lbs.  of  this 
metal  are  generally  melted.  When 
that  quantity  is  melted  down  in 
the  bottom  of  the  forge-hearth, 
a  small  portion  of  it  is  let  off:  it 
should  be  tapped  as  low  at  the 
bottom  as  possible.  This  mass, 
which  flows  like  cast  iron  or  cast 
steel,  is  broken  into  small  pieces, 
and  poimded  into  a  flat  piece  of 
wrought  iron,  which  has  a  brim 
drawn  up  around  it:  this  piece 
serves  as  a  crucible.  It  is  covered 
with  loam,  and  exposed  to  a  heat 
which  will  melt  the  cast  iron,  and 
unite  it  firmly  with  the  wrought 
iron.  The  former  then  forms  a  thin 
coating  of  steel  over  the  one  side 
of  the  iron,  of  immense  hardness. 
This  does  not  become  soft,  even 
though  a  long  time  is  consumed  in 
tempering  it.  Wrought-iron  plates, 
furnished  with  such  a  coating  of 
steel,  are  used  as  draw-plates  for 


wire.  The  holes  for  the  wire  are 
punched  when  it  is  warm;  for,  when 
cold,  its  hardness  is  so  extreme, 
that  no  drill-bit  can  make  any  im- 
pression on  it. 

Iron  for  Blistered  Steel, 

England  is  not  so  celebrated  for 
the  production  of  iron  suitable  for 
the  manufacturo  of  steel  as  Sweden 
and  Russia,  upon  which  countries 
we  must  depend  mostly  for  our 
knowledge  of  the  mode  of  working 
it,  and  the  kind  of  materials  from 
which  iron  for  the  steel  factories  is 
made. 

The  peculiarities  of  such  iron 
are  so  remarkable,  that,  by  means 
of  the  most  accurate  chemical  ana- 
lysis, we  cannot  detect  any  differ- 
ence between  a  given  kind  which 
produces  a  superior,  and  another 
kind  which  produces  an  inferior 
steel.  Were  It  possible  to  detect 
this  difference,  it  would  prove  to 
exist  in  the  cinders.  The  iron  from 
which  blistered  steel  is  made  is  a 
soft,  fibrous,  often  grained,  wrought 
iron,  of  a  peculiar  silvery  white- 
ness. It  is  made  from  mottled  pig 
iron,  smelted  from  magnetic  ore 
by  charcoal  and  cold  blast. 

In  making  pig  iron  for  the  ma- 
nufacturo of  steel,  the  ore  should 
be  carefully  roasted  by  wood,  char- 
coal, or  braise.  The  height  of  the 
blast-furnace  must  not  exceed  35 
feet,  and  the  result  is  still  more 
favourable  when  it  does  not  exceed 
30  feet.  The  boshes  should  mea- 
sure about  9  or  9i  feet.  There 
ought  to  be  either  no  hearth  at  all, 
as  in  the  Swedish  or  Styrian  fur- 
naces, or  one  that  is  very  low. 
Blast  of  medium  strength,  and  tu- 
yeres somewhat  inclined  into  the 
hearth,  are  requisite.  Hot  blast 
must  be  rejected  altogether.  In 
fact,  the  operation  should  be  con- 
ducted in  such  a  manner  as  to  pro- 
duce mottled  iron  of  great  purity. 
In  fluxing  the  ore,  lime  can  be  em- 
ployed, but  only  in  such  limited 


STE 


STEEL,  BUSTBRED. 


STE 


quantity  ai  net  to  cause  the  fimiace 
to  smelt  gray  or  white  iron;  for 
neither  will  be  senriceable  in  the 
manufacture  of  good  steeL 

In  converting  pig  into  bar  iron, 
the  German  forge  is  generally  em- 
ployed in  Sweden,  and  for  this  pur- 
pose may  be  considered  the  most 
perfect.  The  refining  process  re- 
sembles the  boiling  of  iron :  this  is 
required  to  make  the  texture  of  the 
iron  as  uniform  as  possible.  White 
pig  metal  will  not  boil,  and  it  works 
too  fjMt.  Gray  pig  metal  contains 
a  large  amount  of  impurities,  and 
the  greatest  attention  at  the  forge 
will  not  remove  them  in  suAdent 
amount  to  answer  any  practical 
purpose. 

In  making  blistered  steel,  it  is 
essential  to  consider  not  oidy  the 
quality,  that  is,  the  diemical  com- 
position of  the  iron,  but  also  its 
form.  The  bars  are  generally  fiat : 
good  qualities  are  from  an  inch  and 
a  quarter  to  two  inches  in  width, 
and  half  an  inch  thick.  For  ordi- 
nary steel  and  for  cast  steel,  the 
thickness  of  the  bars  may  be  three- 
quarters  of  an  inch;  but  in  these 
eases,  moro  time  is  not  only  re- 
quired in  blistering,  but  the  heart 
of  the  bar  is  still  imperfectly  car- 
bonized. Thin  bars  work  fester, 
and  make  a  more  unifeirm  steel 
than  thiek  and  heavy  bars:  the 
latter  are  always  more  or  less  raw 
inside,  and  contain  too  much  car- 
bon outside.  If  the  iron  is  very 
pure,  it  may  be  short,  that  is,  with- 
out fibres  :  it  may  be  hard,  if  it  is 
at  the  same  time  strong.  Impure 
iron  will  not  make  steel  of  good 
quality.  As  iron  void  of  fibres  is 
generally  more  impure  than  that 
containing  fibres,  the  safest  plan  is 
to  convert  all  the  iron  into  fibrous 
iron.  Coarse  fibrous  iron,  what- 
ever may  be  its  strength,  does  not 
make  good  steel :  that  with  black 
spots  or  streaks  of  cinder  must  be 
avoided  by  all  means.  The  indica- 
tions of  a  good  iron  are,  a  silvery- 
white  colour,  short  fine  fibres,  a 

434  "^^ 


bright  metallic  lustre,  mnd  aa  ag- 
gregatimi  so  uniform,  that  black 
spots  cannot  be  detected  with  a 
lens.  The  transformation  of  bar 
iron  into  steel  reqoirea  bo  apedal 
skill  or  knowledge.  The  quality 
of  the  steel  is  determined  by  the 
quality  of  the  iron  firom  which  it  is 
manufactured. 

Blistered  Sieeh 

The  furnace  for  the  cooTersion 
of  wrought  iron  into  blistered  steel 
is  from  12  to  15  feet  wide,  and  20 
(Mr  25  feet  deep.    A  conical  ehim- 
ney,  40  or  50  feet  high,  is  designed 
to  lead  the  smoke  above  the  roof 
of  the  factory.    The  iron  i»  placed 
in  boxes  composed  of  fire-brick  or 
sandstone  tiles :  these  boxes  are 
frmn  24  to  36  inches  square,  and 
from  10  feet  to  16  feet  in  length. 
Square  holes  at  one  end  of  the 
furnace  serve  for  the  adnuasion  of 
the  iron,  and  the  entrance  and  exit 
of  the  wwkmen.    Holes  are  also  ' 
made  in  the  ends  of  the  boxes, ' 
through  which  one  or  more  of  the , 
bars  may  be  passed,  for  the  pur-  j 
pose  of  testing  the  degree  of  ce-  j 
mentation,  and  the  progresa  of  the  ! 
work.    The  boxes  are  enclosed  in  { 
the  furnace,  which  is  provided  with  , 
a  grate  and  fire-brick  arch.     The  ' 
iron,  when  placed  in  theae  boxes,  < 
Ib  imbedded  and  carefully  laid  edge- ' 
wise  in  a  cement  composed  of  one  ' 
part  hard  charcoal,  one-tenth  part  | 
of  wood  ashes,  and  one-twentieth  | 
part  of  common  salt.  The  mixture  j 
is  ground  into  a  coarse  powder  un- 
der  edge-wheels.    If  the  boxes  are 
10  feet  in  length,  the  iron  bars  may 
be  9  feet  10  inches.     The  cement 
is  laid  about  2  inches  deep  in  the 
bottom  of  the  box.    The  bars  of 
iron  are  then  put  in  edgewise,  se- 
parated by  f  of  an  inch  ^ace,  which 
is  filled  with  cement,  and  the  top 
of  the  bars  covered  to  the  depth  of , 
-^  an  inch.  Upon  this  another  layer : 
of  bars  is  set,  but  in  such  a  manner 
that  the  second  layer  overliea  the  i 
space  which  separates  the  bars  of 


i'<i*i 


\ 


ST£ 


STEBL,  BLISTERED. 


STB 


the  first  layer.  In  tbis  way  the  box 
is  filled  to  mihin  6  inches  of  its 
top.  The  remaiiuxig  space  is  filled 
with  old  cement  powder,  on  the 
top  of  which,  finally,  damp  sand  or 
fire-tiles  are  placed.  The  fire  ought 
to  proceed  slowly,  so  that  three  or 
four  daya  shall  dapse  before  the 
furnace  and  the  cement  boxes  as- 
sume a  cherry-red  heat.  In  fact, 
'  the  fire  should  be  conducted  in 
such  a  manner  that  the  heat  may 
be  slightly  increased  every  day 
during  the  whole  course  of  the 
operation.  A  diminution  of  the 
heaty  frma.  the  time  of  starting,  oc- 
casions a  loss  both  of  fuel  and 
time,  and  is  injurious  to  the  chests. 
A  w^-conducted  heat  will  finish  a 
small  box  in  four,  or  five  days,  and 
a  couple  of  boxes»  3  feet  square,  in 
ten  or  twelve  days.  The  furnace 
and  boxes  should  be  cooled  very 
slowly;  for  a  sudden  change  of 
temperature  is  very  apt  to  break 
the  fire.tiles»  or  sandstone  slabs,  of 
which  the  boxes  are  constructed. 
The  trial'bar,  which  passes  through 
the  small  hole  in  one  of  the  ends 
of  the  box,  and  in  a  eorresponding 
hole  in  the  furnace  wall,  is  some- 
what longer  than  the  other  bars, 
so  as  to  be  taken  by  a  pur  of  tongs, 
and  pulled  out  of  the  box.  There 
are  frequtently  several  of  such  bars, 
for  a  bar  that  is  once  pulled  cannot 
be  returned;  and  if ,  in  a  case  in 
which  there  is  but  one  trial-bar  in 
the  chest,  the  bar  is  pulled  too 
soon,  no  further  opportunity  of 
testing  the  progress  of  cementation 
is  afforded,  lite  trial-bars  are  not 
sufiSclently  long  to  project  over  the 
wall  c^  the  chest.  The  trial-hole  is 
closed  by  a  clay  stoj^ier.  Six  days 
may  be  considered  a  sufficient  time 
for  blistering  bars  of  common  steel, 
such  aa  ^ring  steel,  saw-blades, 
and  oemmoa  ^s ;  eight  days  for 
shear  steel  and  steel  for  common 
cutlery ;  and  ten  or  eleven  days  for 
the  better  qualities  of  steel,  and 
common  ca^t  steeL  Rods  for  the 
finer  sorts  of  blisteredi  and  the 


finest  kinds  of  cast  steel,  are  re- 
tomed  to  the  boxes  after  the  first 
heat,  and  receive  two  or  three  blis- 
tering heats,  according  to  the  qua- 
lity  of  steel  wished  to  be  obtained. 
From  eight  to  twelve  tons  of  iron 
may  be  charged  in  two  chests,  and 
from  four  to  eight  tons  in  case  the 
furnace  contains  but  one  chest. 
Two  small  chests  are  preferable  to 
one  large  chest.  The  smaller  the 
chest,  the  more  uniform  wiU  the 
steel  become.  The  regulation  of 
the  fire  in  the  fomace  ia  a  some- 
what delicate  operation.  Iron  of 
differentqualities  requkesadifferent 
degree  of  beat ;  but  the  heat  can  be 
ea^y  managed  by  recoUectiBg  that 
it  should  be  steadily  increased  every 
day.  If  it  is  not  sufficiently  strong, 
the  iron  will  absorb  but  very  Uttle 
carbon,  and  the  work  wiU  proceed 
slowly.  If  the  heat  is  too  great, 
the  rod  iron  will  be  converted  into 
cast  iron,  or,  at  least,  into  some- 
thing similar  to  it ;  for,  after  being 
once  overheated,  it  will  not,  even 
with  the  greatest  labour  and  atten- 
tion»  make  good  steel.  If  the  heat 
is  carried  so  far  as  to  melt  the  blis- 
tered iron  in  the  boxes,  it  is  con- 
verted into  white  plate-metal, — the 
kind  firom  which  German  steel  is 
manufactured.  But  this  melting 
cannot  weU  take  places  and  if  it 
should  occur,  the  slow  cooling  of 
the  chests,  which  is  equivalent  to 
tempering,  will  transform  the  white 
metal  into  gray  cast  iron.  The 
latter  is  converted  into  steel  with 
greater  difficulty  than  the  white 
metal. 

Blistered  steel,  taken  from  the 
chest,  ia  very  brittle :  the  excellence 
o^  its  qualil^  is  ia  proportion  to  its 
britUeness.  The  presence  of  fibres 
indicates  that  the  cementatioa  is 
unfinished.  A  fine-grained,  white 
aggregatiotttlike  iron  rendered  oold- 
short  by  phosphorus,  indicates  that 
the  cementation  has  not  advanced 
beyond  its  first  stages.  A  crystal- 
line form  of  the  grains  is  an  in- 
dication either  of  imperfect    ce- 


435 


STE 


STEEL,  BLISTERED. 


STE 


mentation,  or  of  too  low  a  heat, 
or  bad  iron ;  still,  the  best  kind  of 
iron  will  exhibit  these  crystals,  and 
they  can  be  observed  by  the  lens, 
if  the  temperature  of  the  chests 
has  not  been  kept  sufficiently  high. 
If  a  good  article  be  desired,  a  repe- 
tition of  the  operation  is,  in  such 
cases,  necessary.  The  grains  of 
good  steel  appear  like  round  glo- 
bules, when  taken  from  the  chest 
and  broken.  After  an  imperfect 
cementation,  the  colour  of  the  steel 
is  white.  Good  blistered  steel  should 
be  of  a  grayish  colour,  and  of  a 
bright  lustre;  and  it  should  exhibit 
a  coarse  grain,  as  though  it  were  an 
aggregation  of  mica  or  leaves  of 
plumbago.  That  which  exhibits  a 
fine  grain,  of  crystalline  form,  and 
which  is  of  a  white  colour,  is  always 
a  poor  article.  But  one  degree  of 
heat  is  favourable  for  each  lund  of 
iron:  if  that  degree  be  hit  upon, 
the  operation  goes  on  well;  if 
otherwise,  a  favourable  result  can- 
not be  expected.  The  composition 
of  the  cement  and  the  construction 
of  the  boxes  and  furnace  have  little 
influence  on  the  quality  of  the  steel. 
"Where  the  iron  is  of  the  best  qua- 
lity, and  where  the  degree  of  heat 
is  most  favourable,  the  fracture  of 
a  bar  taken  from  the  chest  will  ex- 
hibit the  largest  grains  or  leaves. 
An  indication  of  good  iron  is  its 
increase  of  weight  in  cementation : 
while  bad  iron  neither  gains  nor 
loses  in  weight,  iron  of  good  qua- 
lity will  gain  at  the  rate  of  from 
15  to  20  per  cent.  This  applies 
especially  to  strong  and  pure  iron. 
The  surface  of  the  rods,  whatever 
mumber  of  blisters  they  may  have 
when  taken  from  the  chest,  must 
be  clean.  Bad  iron  makes  but  few 
blisters,  or  none  at  all :  the  surface 
of  the  rods  is  rough.  With  the 
quality  of  the  iron  the  number  and 
size  of  the  blisters  increase.  Da- 
nemora  iron  draws  blister  dose  to 
blister,  and  almost  all  of  equal  size. 
Common  iron,  that  is,  charcoal 
iron,  raises  but  few  blisters,  and 


these  are  of  irregular  aize.  The 
best  qualities  of  puddled  iron  raise 
but  few  blisters. 

As  might  be  expected,  the  tex- 
ture and  quality  of  one  bar,  as  well 
as  the  average  which  a  chest  con- 
tains, cannot  be  uniform.  The  in- 
terior of  a  bar,  like  the  interior  of 
the  box,  vrill  be  imperfect,  while 
the  external  parts  wiU  be  overdone. 
The  steel  should,  therefore,  be 
broken,a8sorted,andrefined.  Pieces 
of  uniform  grain,  as  well  as  those 
including  the  extremes  of  q[uality, 
are  piled,  welded,  and  drawn  out 
into  bars.  This  process  must  be 
repeated,  if  the  grain  is  not  suffi- 
dently  uniform  for  the  desired  pur- 
pose. Upon  the  skill  of  the  ham- 
mer-man the  quality  of  the  steel, 
in  a  considerable  degree,  depends. 
Slow  and  heavy  strokes  and  high 
heats  depredate  its  value,  whUe  its 
quality  is  improved  by  a  low  heat 
and  fast  work.  Rolling  steel  in  a 
.rolling-mill,  or  welding  it  in  a  re- 
heating furnace,  makes  it  brittle, 
and  transforms  it  into  a  kind  of 
cast  iron.  This  result,  however, 
can  be  partially  remedied  by  again 
bringing  the  steel  to  the  hammer. 

The  influence  of  the  tilt-hammer 
upon  the  iron  is  no  where  more 
observable  than  in  the  manufacture 
of  steel.  It  is  impossible  to  make 
good  sted  independently  of  proper 
hammer  machinery.  The  tempera- 
ture atwhich  the  hammering  should 
be  performed  is  a  matter  of  consi- 
derable importance :  the  steel  will 
be  spoiled  equally  by  a  too  high  as 
by  a  too  low  heat.  The  secret  of 
success  appears  to  be  the  preven- 
tion of  crystallization,  which  takes 
place  at  certain  temperatures  of  the 
metal.  Under  favourable  condi- 
tions, definite  compounds  of  car- 
bon and  iron  are  formed;  and 
these  compounds  crystallize :  this 
crystallization  causes  brittleness. 
The  greater  the  amount  of  foreign 
matter  which  is  combined  vnth  the 
iron,  the  greater  the  brittleness. 
Blows  of  the  hammer  quickly  re- 


STE 


STEEL,  CAST. 


STE 


peated,  and  the  exposure  of  the 
metal  a  short  time  to  a  low  heat, 
appear  to  he  the  means  of  prevent- 
ing crystallization, — at  least,  of  di- 
minishing its  extent.  A  sudden 
change  of  temperature  augments 
the  power  of  crystallization  in  the' 
highest  degree.  This  makes  the 
iron  hard,  by  giving  rise  to  so 
strong  an  affinity  between  the  iron 
and  foreign  matter,  that  the  colour 
occasioned  by  the  carbon  disap- 
pears. The  carbon  is  enclosed  in 
the  particles  of  iron,  which  is,  in 
turn,  crystallized  by  means  of  its 
strongly  cohesive  properties.  White 
plate-metal  of  great  purity,  con- 
taining carbon  in  large  amount,  is 
harder  than  the  hardest  cast  steel, 
but  the  strength  of  its  cohesive 
properties,  and  the  larger  size  of 
its  crystals,  are  the  causes  of  its 
brittleness.  The  best  steel,  if  melt- 
ed  at  a  high  heat,  similar  to  that  of 
the  blast-furnace,  would  appear  in 
the  same  form  as  plate-metal,  and 
would  be  quite  as  brittle.  From 
the  facts  here  stated,  a  conclu- 
sion may  be  drawn,  that  the  im- 
purities which  increase  the  cohesive 
power  of  steel  or  iron  may  be  re- 
tained, and  the  formation  of  crys- 
tals still  be  prevented. 

Catt  Steel. 

The  irregularity  exhibited  in  the 
texture  of  common  steel  gave  rise 
to  the  invention  of  cast  steeL  Com- 
mon steel  is  broken  into  small 
pieces,  and  closely  packed  into  a 
crucible  made  of  good  fire-clay. 
That  which  is  in  some  degree  more 
highly  carbonized  than  usual  is  best 
adapted  for  cast  steel ;  because,  in 
the  melting  operation,  it  loses  a 
portion  of  its  carbon.  With  the 
fire-clay,  plumbago  or  coke-dust  is 
mixed;  but  neither  of  these  in- 
creases its  durability,  though  di- 
minishing its  liability  to  break  on 
account  of  sudden  changes  of  heat. 
This  well-mixed  mass  is  firmly 
pounded  in  an  iron  mould,  with  a 
moveable  cone  for   the   interior. 

437 


The  crucible  which  is  thus  formed 
is  air-dried  and  slightly  burned  be- 
fore it  is  employed  in  the  melting 
of  cast  steel.  For  this  purpose  a 
crucible  5  inches  wide  at  the  top, 
and  16  or  18  inches  in  height,  is 
generally  employed.  Every  precau- 
tion must  be  taken  to  prevent  it  firom 
cracking ;  for,  in  such  a  case,  its 
contents  are  generally  lost. 

The  air-fiiniaoe  for  the  fusion  of 
the  steel  is  similar  in  construction 
to  those  used  by  brass-founders : 
it  is  2  feet  deep  and  12  inches 
square.  The  fine  at  the  top  is  co- 
vered by  a  cast-iron  trap-door.  The 
top  of  the  furnace  coincides  with 
the  plane  of  the  floor  of  the  labo- 
ratory. Under  the  floor  of  the  lat- 
ter is  an  arch,  into  which  the  grates 
of  the  furnace  may  be  emptied : 
this  arch  supplies  the  furnace  with 
air,  and  in  it  the  ashes  accumulate. 
The  crucible  is  placed  on  a  support 
composed  of  two  thicknesses  of 
fire-brick,  and  its  top  is  covered 
with  a  lid.  In  many  cases,  pounded 
glass  and  blast-furnace  cinders  are 
laid  on  the  top  of  the  steel,  as  well 
to  prevent  the  access  of  air  as  the 
oxidation  of  the  carbon ;  but,  if  the 
lid  fits  well,  this  precaution  is  un- 
necessary :  besides,  these  materials 
generally  tend  to  glaze,  and,  as  a 
consequence,  to  crack  the  crucible. 
In  large  factories,  ten  or  twenty 
furnaces  may  be  put  in  one  row, 
each  furnace  having  its  own  chim- 
ney. In  England,  the  fuel  employed 
is  coke ;  but  anthracite  is  fisr  supe- 
rior to  coke  for  this  purpose.  The 
more  compact  the  fuel,  the  better 
will  be  the  result.  In  feeding  the 
fiimacewith  coal,  great  caution  must 
be  observed;  for  a  sudden  charge 
of  cold  fuel  is  apt  to  crack  the  cru- 
cible. For  this  reason,  square  are 
preferable  to  round  furnaces.  The 
heat  of  the  furnace  must  be  con- 
ducted in  such  a  manner  that  the 
melting  shall  commence  from  be- 
low, and  not  from  the  top.  This 
is  another  reason  why  the  form  just 
described  is  preferable  to  any  other. 


STE 


STENCH-TRAP. 


STE 


AU  these  advantages  are  increased 
by  the  employment  of  blast,  which, 
of  course,  is  essential  where  anthra- 
cite is  used. 

The  time  required  to  mdt  steel 
depends  partly  upon  the  draught 
of  the  furnace,  partly  upon  the 
quality  of  the  crude  steel,  and 
partly  on  the  quality  of  the  article 
designed  to  be  manufactured.  From 
one  to  three  hours  is  generally  re- 
quired for  a  crucible  containing 
50tbs.  of  metaL  The  stronger  the 
steel,  the  greater  the  length  of  time 
consumed.  The  mass  must  become 
perfectly  liquid,  no  matter  how  long 
a  time  is  required  to  produce  this 
result.  The  liquid  steel  is  then 
poured  into  previously  heated  cast- 
iron  moulds,  and  cast  in  the  shape 
of  square  or  octagonal  bars,  2  inches 
thick.  Before  casting,  the  steel  in 
the  crucible  is  stirred  with  a  hot 
iron  rod,  alter  which  a  strong  heat 
is  applied  for  a  few  minutes.  After 
casting,  the  top  of  the  steel  in  the 
mould  is  covered  with  clay,  to  pre- 
vent  its  blistering,  and  to  prevent 
the  access  of  air. 

The  cast  rods  are  exposed  to  a 
cherry-red  heat,  and  put,  when  al- 
most black,  to  the  hammer.  The 
rapid  succession  of  strokes  heats 
the  steel,  and,  if  it  is  very  hard, 
often  in  too  high  a  degree.  Each 
hammer  requires  a  tUter  and  two 
boys.  In  this  case,  as  in  that  of 
blistered  or  German  steel,  hammer- 
ing and  heating  need  the  utmost 
attention.  The  quality  of  the  steel 
depends  upon  the  qidckness  with 
which  the  work  is  performed.  The 
rods  are  heated  in  heating  stoves, 
constructed  like  sheet-iron  ovens. 

SteeleTf  the  foremost  or  aftermost 
plank  in  a  strake,  which  is  dropped 
short  of  the  stem  or  stempost  of  a 
vessel 

Steelyardf  in  statics,  a  kind  of  balance 
""  having  arms  of  unequal  length,  in 
which  the  weight  is  moved  along 
the  longer  arm,  and  becomes  in 
effect  heavier  in  proportion  as  it  is 
removed  from  the  fidcmm  or  sup- 

438 


port.    It  was  formerly  nsmed  ihe 
Statera  Momema^  or  Romsn  baiiace. 

Steeple,  a  spire  or  lantern;  the  super- 
structure attached  to  the  toirer  of 
a  church 

Steerinf-wkeelt  a  wheel  to  which  the 
*    tiller-rope  is  attached,  for  the  con. 
venience  of  steering  a  ship 

Steeting,  in  navigation,  denotes  the 
elevation  which  a  ship's  cathead 
or  bowsprit  is  above  the  stem,  or 
the  angle  which  either  makes  vith 
the  horizon 

Stem,  the  foremost  piece  of  timber  in 
a  ship 

Stem,  in  mining,  a  day's  work 

Stempleet  in  mining,  wooden  pieces 
by  which  to  go  up  and  down  the 
mine,  instead  of  ateps 

Stemeon,  a  piece  wrought  on  the  ait- 
part  of  the  apron,  continued  as 
high  as  the  middle  deck  or  upper 
deck  in  small  ships,  the  tower  eod 
lapping  on  or  acarfing  into  the 
keelson 

Steneh'tn^t  a  contiivanee  for  the 
prevention  of  the  escape  of  effluvia 
from  sinks  and  drains.  These  tnps 


Section  of  Stench-trap. 


Flan  of  Ditto. 


STB 


STILL-HOUSE. 


STI 


are  on  the  same  principle  as  a  gaso- 
meter :  a  cup  inverted  in  water  stops 
the  escape  of  gas.  (See  the  pre- 
ceding plan  and  section  of  a  trap  in 
common  use.)  The  circular  plan 
shows  how  the  fluid  is  drained  off 
through  small  holes.  The  arrows 
in  the  section  show  the  course 
which  the  fluid  takes  in  its  way  in- 
to the  pipe  leading  into  the  drain. 
It  will  be  evident,  from  an  inspec- 
tion of  the  section,  that  the  inverted 
cup  will  be  immersed  in  the  fluid 
as  high  as  the  dotted  lines.  If, 
from  neglect,  the  space  intended 
for  fluid  only  should  be  suffered 
to  become  filled  with  solid  matter, 
the  fluid  will  cease  to  run  in  the 
direction  indicated  by  the  arrows, 
and  the  utility  of  the  traps  will  be 
destroyed :  they  should,  therefore, 
be  kept  constantly  clear  from  solid 
matter. 

Some  persons,  not  understanding 
the  principle  on  which  the  trap 
is  constructed,  remove  the  inverted 
cup  when  the  water  can  no  longer 
flow  through  it,  and  then  leave 
it  off.  The  consequence  is,  that, 
there  being  nothing  to  impede  the 
gas  from  the  drains  from  rising  and 
flowing  into  the  dwelling-houses, 
the  houses  very  frequently  become 
filled  with  noxious  air. 

Siep,  in  ship-building,  a  large  piece  of 
timber  into  which  the  heel  of  a 
mast  are  fixed 

Steptfir  the  masts  are  large  pieces 
fitted  across  the  keelson,  into  which 
the  heel  of  the  mast  is  fixed.  The 
holes  for  the  mast  to  step  into 
should  be  cut  in  proportion  to  the 
steps,  so  as  to  leave  sufficient  wood 
on  each  side  of  the  hole  to  answer 
in  strength  to  the  tenon  left  at  the 
heel  of  the  mast;  and  if  that  should 
be  rather  too  little,  the  hole  may 
be  cut  more  thwartships  to  answer 
the  deficiency  the  fore  and  aft  way. 
There  are  likewise  large  pieces 
called  steps  of  the  cupstands ;  and 
steps  on  ^e  top-side,  for  the  con- 
venience of  getting  on  board. 

Stereobate,  or  StykiatCf  a  base ;  the 


lower  part  or  basement  of  a  build- 
ing or  column 

Stereography,  the  art  of  drawing  the 
forms  of  solids  on  a  plane 

Stereometry,  in  geometry^  the  men- 
suration of  solids 

Stem,  the  aft-part  of  a  ship 

Stem-Jrame,  the  frame  of  timber 
that  is  composed  of  the  stem-post, 
transoms,  and  fashion-pieces 

Stem-poet,  the  straight  piece  of  tim- 
ber at  the  aftermost  part  of  a 
ship,  and  to  which  both  sides  of  the 
ship  unite:  the  lower  end  is  te- 
noned into  the  keel.  It  is  gene- 
rally worked  with  the  but -end 
upwards,  being  most  suitable  to 
the  conversion  of  the  timber ;  but 
in  some  ships  which  trade  to  a  hot 
climate  it  has  been  preferred  to 
work  the  hut-end  downwards,  be- 
cause in  large  ships  it  requires  a 
piece  of  such  growth  whose  juices 
towards  the  but  are  nearly  ex- 
hausted, and  therefore  it  is  sup- 
posed to  last  longer  under  water ; 
whereas,  by  the  heat  of  the  wea- 
ther, when  the  but  is  worked  up- 
wards, it  decays  with  dry-rot  for 
want  of  moisture. 

Stem^heets,  in  navigation,  that  part 
of  a  boat  which  is  contained  be- 
tween the  stem  and  the  hinder- 
most  seat  of  the  rowers 

Stiiff^i  in  navigation,  denotes  the  qua- 
lity by  which  a  ship  is  enabled  to 
carry  a  sufficient  quantity  of  sail 
without  danger  of  oversetting 

StiU-house,  RiUes  are  given  for  build- 
ing these  houses :  the  first  caution 
is  to  lay  the  floor  aslope,  not  flat, 
where  any  wet  work  is  to  be  per- 
formed. It  should  be  also  weU 
flagged  with  broad  stones,  so  that 
no  wet  be  detained  in  the  crevices, 
but  aU  may  run  off  and  be  let  out 
at  the  drains  made  at  the  bottom 
and  sides.  Stills  for  wines  should 
be  placed  abreast  on  that  side  of  the 
still-house  to  which  the  floor  has 
its  current.  Fronting  the  stills,  and 
adjoining  to  the  back  of  the  wall, 
should  hd  a  stage  for  holding  the 
fermenting-backs ;   so  that  these, 


439 


STI 


STONE-COAL  FURNACES. 


STO 


being  placed  at  a  proper  height,  may 
empty  themseKes  by  means  of  a 
cock  and  a  canal  into  the  stills, 
which  are  thns  charged  with  very 
little  trouble.  Near  this  set  of 
fermenting-backs  should  be  placed 
a  pump  or  two,  that  they  may 
readily  supply  them  with  water  by 
means  of  a  trunk  or  canal  leading 
to  each  back.  Under  the  pave- 
ment, adjoining  to  the  stills,  should 
be  a  kind  of  cellar,  whereon  to  lodge 
the  receivers,  each  of  which  should 
be  furnished  with  its  pump  to  raise 
the  low  wines  into  the  still  for 
rectification ;  and  through  this  cel- 
lar the  refuse  wash  or  still-bottoms 
should  be  discharged,  by  means  of 
a  hole  or  other  contrivances. 

Stilobatunif  in  architecture,  denotes 
the  body  of  the  pedestal  of  any 
oolnnm.    (See  Stereobate.) 

Stone  -  Coal  Fumacet  —  ArUhracite 
Fumaeet  (American).  In  Eastern 
Pennsylvania  more  than  sixty  blast- 
furnaces, supplied  by  anthracite, 
are  most  generally  in  operation. 
These  produce  on  an  average  from 
seventy-five  to  eighty  tons  of  iron 
per  week.  This  immense  number 
of  furnaces,  supplied  by  stone  coal 
alone,  was  the  result  of  ten  years' 
industry;  and  the  perfection  to 
which  they  have  been  brought  is  a 
security  that  nothing  can  check 
their  use,  or  prevent  their  exten- 
sion. 

Anthracite  fomaces  resemble,  to 
a  greater  or  less  degree,  coke  and 
charcoal  furnaces.  They  are  sel- 
dom so  high  as  coke  furnaces,  and 
their  horizontal  dimensions  are  usu- 
ally greater  than  those  of  charcoal 
furnaces.  The  following  are  the  di- 
mensions  of  several  of  the  furnaces 
recently  erected  in  Eastern  Penn- 
sylvania. One  belonging  to  Mr. 
Ecket,  at  Reading,  is  37i  feet  in 
height ;  the  top  or  throat  6  feet  in 
diameter;  height  of  hearth,  5  feet ; 
tuy^s,  22  inches  above  its  bottom : 
the  hearth  is  5  feet  square  at  the 
base,  and  6  feet  at  the  top;  the 
boshes  are  inclined  671°,  or  at  the 

440 


rate  of  6  inchea  to  the  foot,  snd 
measure  14  feet  at  their  largest 
diameter.  At  the  point  where  the 
slope  of  the  boshes  joins  the  Uning, 
a  perpendicular  cylindrical  space, 

5  feet  in  height,  conkmences,  and 
from  this  point  the  general  taper  to 
the  throat  is  continued  in  a  straight 
line.  The  hearth,  as  well  as  the 
boshes,  is  buUt  of  coarse  sandstone, 
but  the  latter  are  covered  with  a 
lining  of  fire-brick,  9  inches  thicL 
The  in-wall  consists  of  two  linings, 
and  the  interior  is  the  lining  which 
covers  the  boshes ;  outside  of  this 
is  a  space  4  inches  wide,  filled  with 
coarse  sand,  and  this  is  protected 
by  a  rough  lining  of  slate,  2  feet 
thick.  The  rough  walls  of  the 
stack  are  not  heavy,  but  they  are 
well  secured  by  binders. 

Two  furnaces  erected  at  the 
Crane  Works,  near  Allentown,  may 
be  considered  as  the  greatest  im- 
provement. The  stack  is  35  feet 
high,  40  feet  square  at  the  base, 
and  at  the  top  33  feet.  This  fur- 
nace is  therefore  but  slightly  tapered, 
and  requires  heavy  stone-work.  It 
generates  steam  from  the  tronnel- 
head  gas  flame.  At  most  anthrs- , 
cite  Airnaces,  this  is  done  by  putting 
the  boilers  on  the  top  of  the  for- 
nace.  The  hearth  is  5  feet  high, 
4  feet  square  at  the  bottom,  and 

6  feet  at  the  top ;  the  incUnatioD 
of  the  boshes  is  75^,  and  the  cylin- 
drical part  of  the  in-wall  above  the 
boshes  is  8  feet  high  and  12  feet 
in  diameter.  Fh>m  the  cylindrical 
part  up  to  the  top,  which  is  6  feet 
in  width,  the  in-wall  runs  in  a 
straight  line. 

A  furnace   erected  by  Messrs. 
Reeves  and  Co.,  at  PhcenixviUe, 
is  34  feet  in  height :  the  hearth ; 
is  6  feet  high,  4  feet  3  inches  square ' 
at  the  bottom,  and  5  feet  3  inches  • 
at  the  top :  the  boshes  taper  68^, 
or  at  the  rate  of  rather  less  than 
6  inches  to  the  foot :  they  measure 
13  feet  at  the  widest  part.      Great 
care  is  taken  that  the  lining  and 
the  boshes  form  a  gradual  carve. 


STO 


STONE-COAL  FURNACES. 


STO 


that  sticking  and  scaffolding  in  the 
boshes  may  be  obviated.  The  top 
of  this  furnace  is  8  feet  square. 
There  is  no  doubt  that  the  form 
and  construction  of  these  anthracite 
furnaces  have  been  carried,  veithin 
the  short  space  of  a  few  years,  to 
so  high  a  state  of  perfection  as  to 
leave  but  little  room  for  future  im- 
provements. Their  shape  is  v^orthy 
of  imitation,  particularly  by  Western 
manufacturers ;  for  coaJ  a^pted  to 
all  of  these  furnaces  is  abundant  in 
the  Western  States  of  America. 

Most  of  these  furnaces  generate 
the  steam  for  the  motive  power  of 
the  blast,  as  well  as  the  heat  for  the 
hot- blast  apparatus  at  the  top  of  the 
furnace.  In  this  way  expense  is  not 
only  saved,  but  an  uaiform  genera- 
tion of  steam  and  heating  of  air  are 
produced.  The  cost  of  erecting 
such  a  furnace  cannot  be  readily 
estimated,  as  it  must  depend  greatly 
upon  locdity,  material,  wages,  and 
individual  tastes;  but  it  may  be 
laid  down  as  a  general  rule,  that  a 
stone-coal  furnace  costs  less  than  a 
coke  furnace,  and  that,  in  most 
cases,  a  good  charcoal  stack  can  be 
altered  so  as  to  serve  for  stone 
coal. 

In  the  Western  States,  many 
charcoal  furnaces  are  in  operation, 
and  there  is  no  limit  to  their  ex- 
tension, so  far  as  raw  material, 
wood,  and  ore  are  concerned.  One 
circumstance,  however,  will  neces- 
sitate the  introduction  of  stone-coal 
furnaces  in  the  West,  namely,  the 
price  of  charcoal  iron.  Some  lo- 
calities can  successfully  compete 
against  stone-coal  iron;  but  those 
which,  besides  enjoying  that  ad- 
vantage, are  situated  near  navi- 
gable streams  or  canals,  are  very 
few  in  number.  It  is  said  that 
the  average  cost  of  producing  char- 
coal pig  at  Pittsburgh  is  20  dollars ; 
some  furnaces  produce  it  at  a  cost 
of  15  dollars:  in  as  many  cases, 
however,  25  dollars  is  paid  for  iron. 
The  market-price  at  Pittsburgh 
varies  from  25  to  30  dollars,  accoM- 


ing  to  quality ;  and  at  this  price  little 
profit  is  left  to  the  owners  of  the 
furnaces.  How  far  the  stone-coal 
furnaces  are  in  advance  of  this  will 
be  shown  by  the  following  state- 
ment of  the  average  result  of  three 
years'  smelting.  This  statement 
was  furnished  by  Mr.  Reeves,  of 
Philadelphia : 

Amount  of  material  consumed  to  pro- 
duce one  ton  of  iron  at  anthracite 
furnace  No,  1,  at  Phoemxville, 

Tons. 
Iron  ore  ....  2*59 
Anthracite  coal  .  .  1*83 
Lime 1*14 

Amount  consumed  at  furnace  No,  2, 
at  the  someplace. 

Torn. 
Iron  ore  ....  2*65 
Anthracite  coal  .  .  1*89 
Lime 1*15 

These  furnaces  smelt  brown  he- 
matite, hydrated  oxide  of  iron.  The 
wages  for  producing  one  ton  of 
anthracite  iron,  including  all  inci- 
dental expenses,  amount  to  2  dollars 
50  cents,  to  which  is  to  be  added 
the  interest  on  capital  employed. 

Anthracite  furnaces  require  wider 
tops  than  coke  furnaces,  while  the 
latter  require  far  wider  tops  than 
charcoal  furnaces.    This  width  of 
the  top  may  be  considered  the  most 
essential  Improvement  on  the  blast- 
furnace which  is  suppUed  by  anthra- 
cite coal.     The  height  of  the  stack 
in  anthracite  is  much  less  than  in 
coke  furnaces,  and  jBomewhat  lower 
than  in  charcoal  furnaces.  Anthra- 
cite furnaces  vary  from  30  to  35 
feet  in  height ;  charcoal  furnaces, 
from  30  to  40  feet  in  height ;  and 
coke  furnaces,  from  40  to  60  feet. 
The  width  of  the  trunnel-head  va- 
ries, in  the  United  States,  consider- 
ably. In  Pennsylvania,  Ohio,  Ken- 
tucky, and  Tennessee,  the  vridth  of 
furnaces  at  the  boshes  is  9  and 
often  10  feet,  and  at  the  top  from 
18  to  20  inches ;  or  in  the  propor- 
tion of  30  square  feet  at  the  boshes 
to  1  square  foot  at  the  top.     The 


441 


STO 


STRAP. 


STR 


Cold  Spring  farnace  measures  at 
the  boshes  9  feet,  and  at  the  top 
32  inches :  here  the  proportion  is 
11  feet  at  the  boshes  to  1  foot  at 
the  top. 

The  dimensions  of  charcoal 
furnaces  in  Europe  which  smelt 
refractory  ores,  are  generally  in  the 
proportion  of  5  feet  at  the  boshes 
to  1  foot  at  the  throat ;  frequently 
in  the  proportion  of  4  to  1.  In 
coke  furnaces,  the  proportion  of  the 
horizontal  section  of  the  boshes  to 
that  of  the  top  is  seldom  less  than 
4  to  1,  though  sometimes  even  2*5 

.  to  1.  In  anthracite  furnaces,  the 
diameter  of  the  throat  is  6  feet,  and 
that  of  the  boshes  12  feet ;  that  is, 
in  the  proportion  of  1  to  4.  But 
sometimes  the  boshes  measure  13 
and  the  tops  8  feet  square :  in  this 
case,  the  proportion  is  as  2  to  1. 
Taking  into  consideration  the  small 
height  of  the  stack,  and  the  strong 
blast  which  is  applied,  it  is  found 
that  this  arrangement  in  anthracite 
furnaces  is,  in  an  econondcal  point 
of  view,  very  ftvourable ;  for,  in- 
stead of  retarding,  it  facilitates  the 
vent  of  the  gases.  Narrow  tops 
answer  where  loamy  ore  and  soft 
coal  are  used;  but,  in  such  cases, 
to  obtain  favourable  results,  weak 
blast  and  high  stacks  should  be 
employed.  But  thesf  conditions 
can  be  observed  only  where  coal 
and  labour  are  cheap.  If  any  doubt 
exists  concerning  the  proper  di- 
mensions of  a  furnace,  the  best 
course  is  to  commence  with  a  com- 
paratively low  stack,  wide  throat, 
and  with  as  high  a  pressure  in  the 
blast  as  the  fuel  will  possibly  bear. 

Stone  ochre.  The  true  stone  ochres 
are  found  in  balls  or  globular 
masses  of  various  sizes,  in  the  solid 
bodies  of  stones  lying  near  the  sur- 
face of  rocks  among  the  quarries  in 
Gloucestershire  or  elsewhere.  These 
balls  are  of  a  smooth  compact  tex- 
ture, in  general,  free  from  grit,  and 
of  a  powdery  fracture ;  they  vary 
exceedingly  in  colour,  from  yellow 
to  brown,  murrey,  and  gray,  but 

442 


do  not  differ  in  other  respects  from 
the  Oxfordshire  ochre,  ^and  maj  be 
safely  used  in  oil  or  water  in  the 
several  modes  of  paintiiig,  and  for 
browns  and  dull  reds  in  enamel 

Stoolgf  pieces  of  plank  fastened  to  a 
ship'i  side  to  receive  the  bolting  of 
the  gallery 

Stopper-bolUf  large  ring-bolts  droTC  io 
the  deck  of  a  ship  before  the  main- 
hatch,  for  the  use  of  the  stoppers 

Siqppin^f  in  mining,  catting  down 
mineral  ground  with  a  pick 

Stories,  v\  architecture.  Palladio  di- 
rects that  the  height  of  the  stor} 
immediately  above  the  principal 
floor  be  a  sixth  part  less  than  that 
below;  and  if  there  be  an  attic, 
or  third  story,  it  ahoiild  be  nine- 
twelfths  of  the  height  of  that  im- 
mediately under  it. 

Stoup,  an  old  English  term  for  the 
holy-watei  basin  placed  at  the  en- 
trance to  a  church:  it  is  applied 
also  to  a  vessel  for  carrying  aboot 
anddistributingholy  water  amongst 
a  Roman  Catholic  congregation 

Stroke f  in  ship-bmlding,  one  range  of 
phmks  fore  and  aft 

Strap,  in  carpentry,  an  iron  plate 
placed  across  the  junction  of  tiro 
or  more  timbers,  either  branched 
out  or  straight,  as  may  be  found 
requisite,  and  each  branch  bolted 
or  keyed,  with  one  or  more  bolts 
or  keys,  through  each  of  the  tim- 
bers, for  the  purpose  of  securing 
them  together 

Strata^  in  geology,  extensive  layers 
of  any  mineral  substance,  such  as 
rocks,  &c.  Secondary  strata  are 
nearly  all  comprised  under  the 
heads  of  sandstone,  limestone,  and 
shale. 

Streamers,  in  mining,  the  persons 
who  work  in  search  of  streiun-tin 

Stream-tin,  in  mineralogy,  particles 
or  masses  of  tin  found  beneath 
the  surface  of  alluvial  ground,  and 
separated  from  the  earthy  matter 
by  passing  a  stream  of  water  over 
it:  hence  the  name 

Strength  and  stress  qfmateriaU.  The 
works  of  Barlow  and  Tredgold  con- , 


STR 


STYLES  OP  ARCHITECTURE. 


STY 


tain  the  most  luefiil  information 
on  these  subjects.  Barlow  shows 
that  there  are  four  distinct  strains 
to  which  every  hard  body  may  be 
exposed,  and  which  are, —  Ist,  a 
body  may  be  pulled  or  torn  asun- 
der by  a  stretching  force,  applied  in 
the  direction  of  its  fibres,  as  in  the 
case  of  ropes,  stretchers,  king- 
posts, tie-beams,  &c. ;  2ndly,  it 
may  be  broken  across  by  a  trans- 
verse  strain,  or  by  a  force  acting 
either  perpendicularly  or  obliquely 
to  its  length,  as  in  the  case  of 
levers,  joists,  &c. ;  Srdly,  it  may 
be  crushed  by  a  force  acting  in  the 
direction  of  its  length,  as  in  the 
case  of  pillars,  posts,  and  truss- 
beams;  4thly,  it  may  be  twisted 
or  wrenched  by  a  force  acting  in  a 
circular  direction,  as  in  the  case  of 
the  axle  of  a  wheel. 

Stretchmg-eourtef  in  brick-work  and 
in  masonry,  a  row  or  course  in 
which  the  bricks  or  stones  are 
placed  with  their  longest  faces  ex- 
posed to  view.  The  bricks  or  stones 
thus  laid  are  called  stretchers ;  and 
those  disposed  with  the  ends  out- 
wards are  called  headers. 

Strigaf  in  ancient  architecture,  what 
are  now  called  flutings 

String^  in  mining,  a  small  vein 

String,  the  strake  under  the  gunwale 
within  side,  generally  worked  the 
same  thickness  as  the  sheer-strake, 
and  scarfed  in  the  same  manner : 
the  string  and  sheer-strake  are 
bolted  through  a  ship's  side 

SMng'COurse,  a  narrow,  horizontal, 
and  slightly  projecting  course  of 
brick-work  or  masonry  in  the  wall 
of  a  building 

Stucco,  in  architecture,  a  composition 
of  white  marble  pulverized  and 
mixed  with  plaster  or  Hme,  but  the 
ingredients  vary;  it  is  employed 
commonly  for  fadng  exterior  and 
interior  works ;  it  is  also  sometimes 
used  for  floors 

Stuck  or  Wulf*9  oven,  a  furnace  for 
the  reduction  of  iron,  at  one  time 
common  in  Europe,  now  little  em- 
ployed.   The  interior  of  this  fur- 


nace has  the  form  of  two  cones 
united  at  their  bases :  it  is  usually 
from  10  to  16  feet  high,  24  inches 
wide  at  bottom  and  top,  and  5  feet 
at  the  centre.  There  are  generally 
two  tuyeres,  both  on  the  same  side. 
The  opening  called  the  breast  is 
closed  after  the  furnace  is  heated, 
after  which,  charcoal  and  ore  are 
thrown  in,  and  the  blast  introduced. 
As  soon  as  the  ore  passes  the  tuyere, 
iron  is  deposited  at  the  bottom  of 
the  hearth:  when  this  amounts  to  a 
ton,  the  blast  is  stopped,  the  breast 
wall  removed,  and  the  metal  lifted 
out  in  a  solid  mass,  or  ttuci,  wttlf, 
as  it  is  called  by  the  Germans. 

Studding-sails,  in  navigation,  certain 
light  sails  extended  beyond  the 
skirts  of  the  principal  sails  in  mo- 
derate steady  breezes^  named  also 
'goose-wings' 

Studies,  In  painting,  these  signify 
works  which  a  painter  undertakes, 
to  acquire  a  practical  knowledge  of 
his  art  and  facility  of  execution. 
The  term  is  also  applied  to  the 
parts  taken  separately,  which  the 
artist  afterwards  transfers  to  the 
picture. 

Stuffing-boxes,  in  a  locomotive  engine, 
those  with  recesses  fbr  admitting 
some  soft  material,  such  as  white 
spun -yarn,  to  render  steam-tight 
any  rod  working  through  this  stuf- 
fing or  packing.  The  piston-rods, 
slide-valve  rods,  regulator-rods,  and 
pump-plunger,  all  work  through 
stuffing-boxes  of  this  description. 

Siull,  timber  placed  in  the  backs  of 
bevels  and  covered  with  boards, 
or  small  piles,  to  support  rubbish 

Sturt,  in  mining:  when  a  tributer 
takes  a  pitch  at  a  high  tribute,  and 
cuts  a  course  of  ore,  he  sometimes 
gets  two,  three,  or  five  hundred 
pounds  in  two  months :  this  great 
profit  is  called  '  a  sturt' 

Stylesqf early  ArchitectureinEngland. 
The  severfd  examples,  usually  deno- 
minated Gothic,  are  as  follows: 
1.  The  Anglo-Roman,  which  existed 
about  300  years.  2.  The  Anglo- 
Saxon,  about  450  years.     3.  The 


443 


STY 


SULPHUR, 


SUL 


Anglo-Norman  {which  continued  in 
tue  even  on  the  introduction  qfthe 
Pointed  style),  about  85  years.  4. 
Early  Pointed  (termed  alto  the  Lan- 
cet  style  and  Early  English),  about 
140  years.  5.  The  Pointed  style 
{called  by  someyure  Gothic),  about 
110  years.  6.  The  Florid  Pointed 
{termed  also  the  Perpendicular), 
about  140  years.  7.  The  Tudor, 
Elizabethan,  and  Stuart,  (the  latter 
of  which  is  called  by  Mr.  Britton 
'  the  Revival/)  about  120  years. 

Slyhbate,  the  substructure  of  a 
Greek  temple  below  the  columns, 
sometimes  formed  of  three  steps, 
which  were  continued  round  the 
peristyle ;  and  sometimes  of  walls 
raised  to  a  considerable  height,  in 
which  case  it  was  approached  by  a 
flight  of  steps  at  one  end 

Subtangent,  in  geometry,  in  any  curve, 
is  the  line  which  determines  the 
intersection  of  the  tangent  in  the 
axis  prolonged 

Subtense,  in  geometry,  the  chord  of 
an  arch;  that  which  is  extended 
under  any  thing 

Sucker,  in  mechanics,  the  embolus  or 
piston  of  a  pump.  In  pneumatics, 
a  round  piece  of  leather,  which, 
laid  wet  on  a  stone  and  drawn  up 
in  the  middle,  leaves  a  vacuum 
within,  which,  by  the  pressure  of 
the  atmosphere,  makes  it  adhere. 

Sulphate  of  copper  (blue  vitriol),  in 
chemistry,  metallic  salt,  a  com- 
pound of  sulphuric  add  and  copper 

Sulphate  of  iron  (copperas  or  green 
vitriol),  in  chemistry,  a  metallic 
salt,  a  compound  of  sulphuric  acid 
and  iron 

Sulphate  qflead,  an  exceedingly  white 
precipitate  from  any  solution  of 
lead  by  sulphuric  acid,  much  re- 
sembling the  blanc  d*argent,  and 
which  has,when  well  prepared,  quite 
neutral,  and  thoroughly  edulcorated 
or  washed,  most  of  the  properties 
of  the  best  white-leads,  but  is  rather 
inferior  in  body  and  permanence 

Sulphate  qf  lime  (gypsum,  &c.),  in 
mineralogy,  a  compound  of  sul- 
phuric  acid  and  lime 

444 


Su^hate  qf  zinc  (white  vitriol),  iii 
chemistry,  metallic  salt,  a  com- 
pound of  sulphuric  acid  ajid  zinc 

Sn^huTf  a  simple  combustible  sab- 
stance  found  native  in  a  loose 
powder,  either  detached  or  in  veins. 
It  is  met  with  in  the  neighbourhood 
of  volcanoes,  where  it  is  deposited 
as  a  crust  on  stones  contig;aous  to 
them.  It  can  be  prepared  by  ex- 
posing iron  pyrites  .to  heat,  when 
part  of  the  sulphur  is  driven  off  in 
vapour,  and  may  be  collected  in 
water:  when  vaporized,  it  condense 
in  small  crystalline  particles,  called 
flowers  of  sulphur.  It  is  inflam- 
mable, burning  slow  with  a  psle 
blue  flame.  Sulphur  is  ^oand  in 
connection  with  silver,  copper,  lesd, 
antimony,  and  iron.  Sulphur  oc- 
curs, in  nature,  crystallized  in  acute 
octahedrons  with  rhomhic  bases. 
It  is  principally  brought  to  this 
country  from  Sicily. 

StUphuret  of  hydrogen.  This  gas,  com- 
monly known  as  sulphuretted  hr- 
drogen,  is  invaluable  as  a  re-agent 
in  separating  one  class  of  metals 
from  another,  is  precipitated  by 
it  in  acid  solutions  from  another 
gas,  and  only  acted  upon  by  it  in 
alkaline  solutions. 

Su^hurets  of  iron. — Iron  has  a  very 
great  affinity  for  sulphur:  there 
are  five  definite  compounds  of  these 
substances.  It  is  very  diflicult  to 
separate  iron  from  sulphur  by  heat 
alone.  Of  the  five  different  com- 
positions,  two  only  deserve  at- 
tention, — ^the  white  and  the  yellow 
sulphurets. 

White  sulphuret  qf  iron  {white 
pyrites)  abounds  in  coal-beds,  and  , 
in  the  accompanying  strata  of  clay;  ■ 
also  in  regular  veins,  along  vrith 
ores  of  lead,  copper,  and  iron,  in , 
the  transition  rocks.     Before  thai 
flame  of  the  blow-pipe,  it  becomes ' 
red ;  upon  charcoal,  the  sulphur  is 
evaporated,  and  oxide  of  iron  re- ' 
mains.    It  is  very  liable  to  decom- 
position :   it  is  preferable  to   the ; 
yellow  kind  in  the  manu£scture  of  > 
copperas,  and  is,  in  coal  mines,  the  | 


SUM 


SURVEYING. 


SUR 


most  dangerous  of  any,  as  it  often 
decomposes  so  quickly  as  to  kindle 
the  coal-slack.  Its  composition  is, 
in  100  partSy 

45*07  iron   ■ 
53*35  sulphur 
0*58  manganese 


99*00  white  pyrites. 

Yellow  sulphuret  of  iron,  yellow 
pyrites.  —  This  variety  becomes 
red  before  the  blow-pipe;  and  in 
the  reducing  flame  it  melts  into 
a  globule,  which  continues  red-hot 
for  a  short  time,  and  possesses,  after 
cooling,  a  crystalline-  appearance. 
In  nitric  acid  it  is  slowly  soluble, 
-with  the  precipitation  of  sulphur, 
but  in  no  other  acid.  It  is  com- 
posed of 

47*30  iron 
52*70  sulphur 


100*00  yellow  pyrites. 

Yellow  pyrites  is  almost  identical 
with  the  white  pyrites,  and  the  lat- 
ter appears  to  be  only  different  in 
containing  more  foreign  matter : 
both  are  widely  diffused  among  the 
ores  of  iron,  and  are  found  in  mas- 
sive nodules,  crystals,  and  veins,  in 
the  coal  beds,  clay-slate,  graywacke, 
greenstone,  limestone,  and  in  beds 
of  primitive  slate.  It  is  the  main 
material  wliich  is  used  for  manu- 
facturing copperas,  alum,  oil  of 
vitriol,  Spanish  brown,  and  sulphur. 
Summevt  a  horizontal  beam  or  girder 
Sumpf  in  mining,  a  pit  sunk  in  the 
engine-shaft  below  the  lowest  work- 
ings 
Sumpshaftf  the  engine-shaft 
SuperciUuniy  the  transverse  antepag- 
ment  of  a  doorway.  The  word  is 
also  used  to  denote  the  small  fillets 
or  bands  above  and  below  the  scotia 
of  the  Ionic  base. 
Superficies,  in  geometry,  the  surface 
of  any  body  or  figure,  considered 
as  possessing  two  dimensions,  or 
extension  in  length  and  breadth, 
but  destitute  of  thickness :  in  men- 
suration, it  is  estimated  as  area 

445 


Supporters,  in  heraldry,  figures  stand- 
ing  on  a  scroll  and  placed  by  the 
side  of  the  escutcheon,  such  as  the 
lion  and  the  unicorn  in  the  British, 
and  the  angels  in  the  French  arms 

SupporterSfin  ship-building,  the  knee- 
pieces  under  the  cathead 

Surmarks,  in  ship-building,  the  sta- 
tions of  the  ribbands  and  harpings 
which  are  marked  on  the  timbers 

Surveying  is  the  art  of  applying  the 
principles  of  geometry  and  trigo- 
nometry to  the  measurement  of 
land.  The  principal  operations  are 
laying  down  or  driving  base  lines 
and  triangles  on  either  side  of  the 
base.  In  large  surveys  it  is  de- 
sirable to  lay  down  these  triangles 
by  measuring  each  angle  with  an 
instrument  called  the  theodolite, 
by  which  the  accuracy  of  the  mea- 
surement of  the  sides  may  be  check- 
ed. The  theodolite  is  also  avail- 
able in  fixing  the  true  position  of 
points,  the  distances  between  which 
are  immeasurable,  owing  to  the 
intervention  of  buildings,  rivers,  or 
other  obstacles.  Rectangular  or 
irregular  areas  of  laud  are  similarly 
reduced  to  triangles,  and  their  exact 
position  referred  to  a  base  line.  In 
driving  lines  over  land,  three  long 
poles  are  requisite :  these  are  ranged 
in  the  direction  of  the  intended 
line  at  the  greatest  distance  at 
which  they  can  be  seen,  either 
vfith  the  naked  eye  ,  or  with  the 
assistance  of  a  telescope,  and  driven 
firmly  into  the  ground.  Inter- 
mediate stakes  are  then  fixed,  by 
which  the  line  is  marked  out.  In 
proceeding  onward  to  extend  the 
line  included  between  the  front  and 
back  pole,  the  latter  only  is  re- 
moved, and  carried  before  the  front 
pole  to  the  greatest  practicable  dis- 
tance, and  being  ranged  by  the  two 
remaining  poles,  is  there  driven. 
Thus  the  middle  pole  becomes  the 
back  one,  and  is  in  like  manner 
removed  to  the  "front,  and  there 
ranged  and  fixed:  and  in  this 
manner,  by  successively  removing 

.    the  back  pole,  and  conveying  it  to 


SUR 


SUSPENSION. 


SU8 


the  front,  the  line  is  extended  as 
far  as  necessary.  These  poles  should 
be  as  light  as  possible,  consistent 
with  strength,  and  shod  with  iron 
points,  to  fadlitate  driving.  On 
the  top  of  each  pole  a  flag  or  disc 
is  fixed,  to  render  them  conspicuous 
from  a  long  distance.  Distances 
are  measured  with  a  chain  formed 
of  wire  links,  the  length  of  the 
chain  being  66  feet,  and  formed 
with  100  links,  each  link  measuring 
7*92  inches.  The  end  of  each  chain 
is  marked  by  driiring  a  wire  pin  or 
arrow  into  the  ground,  by  counting 
which  the  number  of  chains  mea- 
sured is  ascertained.  The  base 
line  being  thus  driven  and  measured, 
it  is  recorded  in  a  book,  and  all 
intersections  of  fences,  &c.  marked, 
and  their  relative  distances  on  the 
base  are  entered.  A  distant  point 
on  either  side  of  the  base  is  then 
determined,  and  a  pol^  erected 
upon  it,  and  the  distance  of  this 
point  from  two  fixed  points  upon 
the  base  measured  with  the  chain, 
and  duly  recorded.  By  this  means, 
a  triangle  is  completed,  and  after- 
wards correctly  filled  in  with  all 
intervening  fences,  Sec;  and  by  re- 
peated processes  of  this  kind  the 
survey  is  extended  to  any  required 
distance  on  each  side  of  the  base. 
If  the  triangles  first  laid  down  are 
of  great  extent,  they  should  be  de- 
termined, and  the  position  of  their 
angles  ascertained  with  the  theodo- 
lite. This  instrument  consists  of  a 
pair  of  horizontal  circular  plates, 
the  upper  of  which  is  called  the 
vernier  plate,  turning  freely  on  a 
centre  upon  the  lower  plate,  the 
edge  of  which  is  chamfered  off,  and 
accurately  graduated  with  degrees 
and  subdivisions.  By  these  plates 
and  their  adjusting  screws,  &c., 
horizontal  angles  are  measured,  the 
sight  of  the  surveyor  being  aided 
by  a  powerful  telescope  on  the 
upper  part  of  the  instrument,  and 
a  microscope  to  read  off  the  gradu- 
ations upon  the  vernier.  An  upper 
frame  which  carries  the  telescope 

■46 


also  supports  a  vertical  arc  or  kdu- 
circle,  which  is  likewise  graduted, 
and  with  the  aid  of  another  micro- 
scope the  elevation  of  any  high  ob- 
ject, as  a  tower,  &c.  (obserred 
through  the  tdescope)  may  be 
correctly  read  off.  This  part  d 
the  apparatus  thus  enables  verticil 
angles  to  be  raeasored,  and  by  tbe 
application  of  trigonometry  heights 
or  distances  may  be  thus  exactly 
determined  without  the  actual  mea- 
surement of  all  the  lines  in  each 
vertical  triangle. 

Siiipensitmf  in  mechanics,  as  in  a 
balance,  are  those  points  in  the 
axis  or  beam  where  the  weights  are 
applied,  or  from  which  they  are 
suspended 

Suspetuion.  Bridges  of  suspensioa 
are  of  several  kmds  and  of  various 
dimensions,  consisting  of  several 
iron  chains,  not  formed  of  smaO 
links,  like  cables,  but  of  whole  bars 
of  iron  jointed  at  their  ends,  passed 
over  a  tower,  being  the  access  to 
the  bridge  on  each  side  of  the  river, 
while  their  extreme  ends  are  fiimlj 
attached  to  large  and  ponderous 
stones  that  are  sunk  a  great  depth 
into  the  ground  on  each  side  of  the 
stream.  These  masses  of  masonry 
are  named  abuttnentt.  The  chsins 
hang  in  parallel  festoons  over  the 
river,betweenthesupportingtowers, 

and  carry  a  number  of  vertical  bars 
of  iron  that  are  attached  to  and 
hang  down  from  them  for  tbe  por- 
pose  of  suspending  beams  of  wood 
or  iron  hanging  horizontally  in  the 
direction  of,  or  obliquely  to,  the 
stream,  and  serving  as  joists  to 
support  a  strong  planked  platform 
or  roadway  that  extendi  across  the 
river:  frequently  these  roadways 
are  paved,  or  at  least  gravelled  or 
ballasted  over  for  horses,  carriages, 
and  pedestrians.  Extraordinary  ex- 
amples exist  of  this  species  olbwH^' 
ing  in  our  own  country,  vis.  that  at 
Bangor,  crossing  the  Menai  Strait, 
by  Telford,— that  at  Hammersmith, 
by  Tierney  Clark,— Hungcrford,  by 
Brunei;  but  the  most  extraordi- 


SWE 


STPHON. 


SYP 


nary  straetiiK  is  the  stupendous 
work  of  Tierney  Clark,  uniting 
Pesth  with  Buda,  in  Hnngtry.  Mr. 
Dredge  has  eonstrueted  several 
smaller  bridges  of  suspension^  ac- 
cording to  his  arrangement,  both 
in  England  and  Scotland,  andlieut.- 
Col.  Goodwyn  also,  in  India,  ivith 
some  modifications  of  Dredge's  ad- 
justments. Suspension  bridges  have 
been  constracted  also  with  wire  as 
a  material  at  Fribourg,  in  Switzer- 
land, and  at  other  places. 

Sweep f  or  TiUer-Swe^t  &  circular 
plank  fitted  to  support  the  foremost 
end  of  the  tiller,  or  handle  of  a 
rudder,  much  improTod  by  convey- 
ing the  tiller-rope  round  it,  and 
keeping  it  always  tight 

Swioelf  in  mechanics,  something  fixed 
in  another  body  so  as  to  turn  round 
on  it;  a  Idnd  of  ring  made  to  turn 
round  in  a  staple  or  other  ring. 
In  artillery,  a  very  small  cannon, 
which  carries  a  shot  of  about  half- 
a-pound. 

Sycamore^treei  a  species  of  the  ficus, 
or  fig-tree,  common  to  Europe; 
^also  called  the  great  maple,  and  in 
Scotland  and  the  north  of  England 
the  plane-tree :  its  mean  size  is  32 
feet  high.  It  is  a  very  clean  wood, 
resembling  the  plane-tree,but  much 
smaller.  The  colour  of  the  young 
sycamore  is  silky  white,  and  of  the 
old,  brownish  white ;  the  wood  of 
the  middle  age  is  the  intermediate 
in  colour,  and  the  strongest.  It  is 
used  in  fiimiture,  piano-fortes,  and 
harps,  and  for  the  superior  kinds 
of  Tunbridge  ware.  Sycamore  may 
be  cut  into  very  good  screws,  and 
is  used  for  presses,  dairy  utensils, 
&c 

Symmetry t  in  sculpture,  &c.,  adaption 
of  parts  to  each  other ;  proportion ; 
harmony;  agreement  of  one  part 
with  another 

SympiesometeTf  a  barometrical  instru- 
ment  in  which  the  atmospheric 
pressure  is  indicated  by  the  Itfcent 
of  a  column  of  oil  in  a  short  glass 
tube  against  the  elastic  pressure  of 
an  enclosed  volume  of  hydrogen 

447  """" 


gas.  Its  indications  require  correc- 
tion for  the  changes  produced  by 
temperature  on  the  gas.  The  in- 
strument is  more  compact,  but  also 
more  complex,  than  the  mercurial 
barometer. 

Synagogue,  a  word  which  primarily 
sign^ed  an  assembly,  but,  like  the 
word  church,  came  at  length  to  be 
applied  to  places  in  which  any  as- 
semblies, especially  those  for  the 
worship  of  God,  met,  or  were  con- 
vened. Jewish  synagogues  were 
not  only  used  for  the  purposes  of 
divine  worship,  but  also  for  courts 
of  judicature.  The  present  ordi- 
nary meaning  of  the  term  syna- 
gogue is  a  Jewish  church. 

Syphermg,  in  ship-building,  lapping 
one  edge  of  a  plank  over  the  edge 
of  anoth«-  for  bulk-heads,  making 
the  edges  of  the  planks  and  the 
sides  of  the  bulk -head  plain  sur- 
faces 

Syphon,  a  bent  tube,  having  one  leg 
shorter  than  the  other.  It  acts 
from  the  pressure  of  the  atmo- 
sphere being  removed  from  the 
surface  of  a  fluid,  which  enables  it 
to  rise  above  its  common  level,  and 
is  used  for  the  purpose  of  emptying 
liquors  from  casks,  &c. 

Syphon.  The  date  of  the  first  appU. 
cation  of  the  principle  by  which 
water  or  other  fluids  may  be  drawn 
firom  one  level  to  another  by  the 
eslianstion  of  the  air  contained  in 
the  limb  communicating  with  the 
lower  level,  appears  to  be  very 
remote.  The  Egyptians  certainly 
used  it  for  the  trans\'asing  of  wine : 
but  the  first  important  application 
of  this  principle  to  useful  or  general 
practice  was  in  the  aqueduct  which 
conducted  the  springs  of  Mount 
Pila  to  Lyons:  the  date  of  this 
aqueduct  is  about  40  years  after 
the  commencement  of  the  Christian 
era.  Upon  the  total  length  of  the 
aqueduct,  which  with  its  branches 
was  15  old  French  posting  leagues, 
there  were  three  large  syphons  to 
carry  the  water  from  the  upper 
sides  of  the  same  number  of  valleys 


8YP 


SYPHON. 


SYP 


to  the  lower.  Of  these,  the  valley 
of  Chaponest  was  2400  feet  across, 
measuring  in  a  straight  line  across 
the  yailey;  and  it  was  about  200 
feet  deep.  The  valley  of  St.  Foy 
was  about  3192  feet  across,  by  300 
feet  deep ;  that  of  St.  Tren^e  was 
798  feet  across,  but  much  shal. 
lower. 

The  pipes  of  the  Chaponest  sy- 
phon, on  leaving  the  upper  reser- 
voir,  were  8  inches  diameter  and 
1  inch  thick :  they  were  of  lead. 
After  running  75  feet  of  the  descent 
of  this  dimension,  they  branched 
off  into  two  divisions  of  6  inches 
diameter  each,  in  order  that  the 
pressure  upon  the  pipes  at  the 
lower  portion  of  the  syphon  might 
be  diminished.  They  ran  over  the 
level  bridge  in  the  lower  part  of 
the  valley  of  this  smaller  diameter, 
and  mounted  the  opposite  side  for 
a  height  of  70  feet,  when  they  re- 
united into  pipes  of  8  inches  dia- 
meter again.  The  total  fall  of  the 
Chaponest  syphon  was  150  feet, 
the  rise  on  the  opposite  side  was 
130  feet,  leaving  a  difference  of 
level  of  20  feet  to  compensate  for 
the  friction.  The  syphon  of  St. 
Foy  had  a  difference  of  level,  from 
the  upper  reservoirs  to  the  straight 
part,  of  240  feet. 

The  Lyons  aqueduct  had  in  its 
total  length  thirteen  common 
straight  aqueduct  bridges  and  three 
syphons;  it  delivered  very  nearly 
1,300,000  gallons  in  the  twenty, 
four  hours. 

Dr.  Lardner  and  many  other 
writers  on  hydraulics  have  failed 
to  notice  these  extraordinary  works, 
and  have  expressed  their  surprise 
that  the  ancients  were  ignorant  of 
the  existence  of  the  law  by  which 
water  finds  its  own  level.  The  an- 
cients, however,  appear  to  have 
wisely  preferred  the  more  econo- 
mical system  of  carrying  water  in 
a  straight  trough,  wherever  the  ex- 
pense was  justifiable.  Water-works 
were,  in  early  times,  Government 
affairs,  and  the  expense  of  their 

448 


maintenance  vtbs  deliberated.  The 
preceding  cases  abundantly  prove 
that  the  ancients  applied  the  well- 
known  law  of  hydrostatical  balance 
whenever  they  found  such  a  course 
advisable ;  and  the  details  given  by 
Yitruvius  remove  all  doubt  upon 
the  subject.  His  instructions  (lib. 
8,  c.  7)  are  as  follows: — "When 
the  expense  of  erecting  a  bridge 
is  too  great,  a  syphon  may  be 
used;  but  this  should  only  be 
resorted  to  as  a  last  expedient 
The  danger  of  bursting  the  pipes, 
and  the  expense  of  the  repairs, 
are  serious  objections  to  this  me- 
thod, andin  the  end  straight  bridges 
are  the  cheapest.  If,  however,  it 
be  determined  to  employ  a  syphon, 
it  should  be  laid  with  a  regular 
curve,  and aUabrupt elbows  avoided. 
To  securethis,  a  substructure  should 
be  raised  to  fill  in  any  inequalities 

.  in  the  valley  where  it  is  to  be 
erected.  The  last  length  of  the 
descending  pipe  and  the  first  of  the 
straight  pipe  at  the  level  part,  as 
also  the  last  length  of  the  straight 
pipe  and  the  first  ascending  one, 
should  be  let  into  a  solid  stone, 
which  should  be  carefiiUy  fixed 
and  surrounded  with  ballast,  pro- 
perly rammed."  He  also  gives  di- 
rections for  the  construction  of  air- 
shafts  from  the  lower  parts,  which 
he  calls  *  columnaria,'  and  he  ex- 
pressly states  that  they  are  neces- 
sary to  relax  the  'vis  spiritus  in 
ventris,' — the  force  of  the  air  in 
the  curves. 

Syphon^cupSf  in  steam  engines,  cups 
placed  for  feeding  oil  to  the  work- 
ing parts  of  the  machinery,  trim- 
med with  cotton  or  worsted,  the 
same  as  the  axle-boxes 

SyringCt  a  small  hand-pump:  in  its 
simplest  form,  it  is  provided  with  > 
a  pistoa  and  rod,  but  is  destitute  \ 
of  valves,  one  simple  aperture  at  | 
the  extremity  serving  for  the  ad-  , 
mission  and  ejection  of  fluid :  those 
constructed  with  valves,  however,  , 
are  available,  on  a  smaller  scale, 
for  all  the  purposes  of  an  air-pump 


SYS 


TALMUD. 


TAL 


SystylCi  a  term  applied  to  a  building 
in  i^rhich  the  pillars  are  closely 
placed,  but  not  quite  so  close  as  in 


the  pycnostyle,  the  inter-columni. 
ation  being  only  two  diameters,  or 
four  modiUes,  of  the  columns 


TAB 

Taberd  (Saxon),  a  jerkin,  or  coat 
without  sleeves;  also,  a  herald's 
coat 

rad^nuie/e,  a  moveable  fabric;  among 
the  Jews,  the  name  of  a  portable 
temple  which  was  constructed  in 
the  Wilderness:  the  term  is  also 
applied  in  Christian  architecture 
to  richly  ornamented  niches 

Table,  in  architecture,  a  smooth, 
simple  member  or  ornament  of 
various  forms,  but  most  usually  in 
that  of  a  long  square 

Table  or  Tablet  mouldings^  horizontal 
bands  of  mouldings,  such  as  base- 
mouldings,  strings,  cornices,  &c. 

Tables  were  in  the  Tudor  age  usually 
described  as  '  hordes,'  and  were  not 
in  any  great  variety:  the  sorts  were 
but  few,  and  little  distinguished  by 
-workmanship;  but  the  splendour 
of  their  coverings  amply  compen- 
sated for  the  rudeness  and  simplicity 
of  the  works  so  concealed.  The 
most  elaborate  embroidery,  wrought 
on  the  finest  grounds,  velvets  and 
satins  fringed  with  gold  and  silver, 
Turkey  carpets,  and  the  choicest 
tapestry,  were  used  as  table-covers. 

Tahle-elotJis,  carpets,  which  at  earlier 
periods  were  almost  the  only  cover- 
ings for  dining -tables  and  cup- 
boards; napinff  was  possessed  by 
the  higher  orders  only.  In  1520, 
Thomas,  Duke  of  Norfolk,  be- 
queathed his  rugjerie  to  Agnes  his 
wife. 

TabUnfff  in  ship-building,  letting  one 
piece  of  timber  into  another,  in  the 
same  manner  as  the  beams  are  put 
together 

TabHnum,  an  apartment  of  a  Roman 
house  which  was  entered  imme- 
diately from  the  atrium,  and  in 
which  records  were  preserved  in 
cases,  and  the  hereditary  statues 
placed. 

449 


TAG 

Tackf  in  navigation,  to  change  the 
course  or  turn  about  a  ship  during 
a  contrary  wind  from  the  starboard 
to  the  larboard,  &c. 

Tack,  in  navigation,  a  rope  used  to 
confine  the  clues  of  the  main  and 
fore  courses  forward,  occasionally 
in  a  fixed  position :  it  has  a 
large  wall-knot  at  one  end.  The 
word  has  also  various  other  appli- 
cations. 

Tackf,  in  navigation,  the  foremost 
lower  comer  of  all  fore  and  aft  sails 

Texking,  in  navigation,  signifies  a 
manoeuvre  by  which  a  ship  makes 
an  oblique  progression  to  windward 
in  a  zig-zag  direction,  named  also 
*■  beating  to  windward' 

Tackle,  in  mining,  the  windlass,  rope, 
and  kibble 

T^tenta,  the  band  or  fillet  surmounting 
the  Doric  epistylium 

Taffrail,  the  carved  work  at  the  upper 
part  of  the  stem  of  a  vessel,  the 
ends  of  which  correspond  with  the 
qusurter-pieces 

Tail'Waier,  the  wastewater  discharged 
from  the  buckets  of  a  water-wheel 
in  motion 

Talmud,  or  ThalmMd,  a  book  in  great 
veneration  among  the  Jews,  con- 
tainingtheir  doctrines  and  morality, 
of  which  there  are  two,  the  old, 
called  the  Talmud  of  Jerusalem, 
the  other,  of  Babybn;  the  first 
composed  by  Rabbi  Johanan,  pre- 
sident of  the  academy  of  Palestine, 
about  the  300th  year  of  Christ: 
this  consists  of  two  parts,  the 
Mishna,  or  the  second  law,  con- 
taining the  traditions  of  the  Jewish 
doctors,  collected  about  the  year 
190  by  Rabbi  Judah ;  and  the  Ge- 
mara,  or  the  finishing  or  completing 
the  whole,  which  was  done  by 
Johanan,  and  published  both  to- 
gether.   The  Talmud  of  Babylon 


TAL 


TAPESTRY. 


TAXI 


contains  also  the  Mithna,  and 
the  Gemara  of  RabM  Asa,  of  Baby- 
lon, about  ihe  year  400:  this  is 
much  more  valued  than  the  other, 
on  account  of  its  great  clearness 
or  perspicuity,  and  also  for  its  ex- 
tensiveness,  though  it  abounds  in 
fables  and  ridiculous  stories,  which 
the  Jews  entertain  with  such  eager- 
ness, that  they  compare  the  Bible 
to  water,  the  Mishna  to  wine,  and 
the  Gemara  to  hippocrass,  affirming 
that  Moses  revealed  those  traditions 
and  explications  to  Aaron,  to  his 
sons,  and  the  elders,  and  that  he 
received  them  from  God. 

TabtSf  in  architecture,  the  inclination 
or  slope  of  a  work,  as  the  outside 
of  a  wall,  where  its  thickn^s  is 
diminished  by  degrees  as  it  rises 
in  height 

Tanynnff,  in  mining,  the  material,  usu- 
ally soft  stone,  placed  upon  the  gun- 
powder to  confine  its  force,  which 
would  otherwise  pass  up  the  hole ; 
also  the  process  of  placing  the  ma- 
terial 

Tamjirinff-iron,  a  tool  used  for  beating 
down  the  earthy  substance  in  the 
charge  used  for  blasting 

Tanffeni,  in  geometry,  a  right  line 
perpendicularly  raised  on  the  ex- 
tremity of  a  radius,  which  touches 
a  circle  so  that  it  would  never  cut 
it,  although  infinitely  produced,  or, 
in  other  words,  it  wouM  never 
come  within  its  circumference 

Tanlif  that  part  of  the  tender  of  a  lo- 
comotive engine  which  contains 
the  water :  tanks  vary  in  size,  ac- 
cording to  the  power  of  the  engine 
to  which  they  are  attached,  and  are 
from  about  500  to  1600  gallons  in 
capacity 

Tapf  in  mechanics,  a  hardened  steel 
screw  with  a  square  head,  so  that  it 
may  be  turned  by  a  wrench :  it  is 
grooved  from  end  to  end,  and  is 
also  slightly  tapered :  it  is  used  for 
cutting  an  internal  screw,  as  that 
of  a  nut,  &c. 

Tt^*wrmchf  the  handle  for  turning  a 
wrench 

'^oper,  a  gradual  diminution  in  the 

I50 


size  of  a  body,  so  as  to  form  a  wedge 
or  cone 

TyteT' chain  bridge^  a  auapensioa 
bridge  invented  by  Mr.  Dredge. 
(See  Dredge^ 9  Suspension  Bridge,) 

Tapestry,  or  Arras,  described  as 
'hangings,'  enriched  the  walls  of 
saperior  apartments  from  very  early 
times:  the  most  ancient  t^estiy 
now  existing  is  preserved  in  the 
church  of  Bayenx,  in  Normandy, 
and  exhibits  an  entire  series  of  the 
drcnmstances  attending  William 
the  Conqueror's  descent  in  Eng^d. 
The  arras  was  loosely  hung  in  pro- 
jecting frames,  by  tenter  -  hooks, 
against  the  walls,  which  were  some- 
times not  even  plastered,  covering 
the  whole  surface  from  the  floor  to 
the  ceiling,  and  was,  like  most  other 
frimiture,  removeable  from  one  resi- 
dence of  its  owner  to  another.  The 
most  costly  materials  were  em- 
ployed in  the  fabrication  of  the 
bMt  sort  of  hangings.  The  apart- 
ment of  Henry  YIII.  at  Calais, 
whither  he  was  accompanied  from 
Boulogne  by  Francis  I.  in  1520,  was 
hung  with  doth  of  gold,  adorned 
with  precious  stones  and  pearis.  In 
the  old  inventories,  doth  of  gold, 
and  cloth  of  silver,  and  emhvoidery,  ' 
frequently  occur,  as  well  as  doth 
of  silk  and  gold  mixed,  called  haud- 
kin.  The  walls  ofthe  gallery  at  York 
House,  the  residence  of  Cardinal 
Wolsey,  which  was  seized  by  the 
king,  were  **  hanged  with  doth  of 
gold,  and  tissue  of  divers  makings, 
and  cloth  of  silver  likewise  on  both 

.  sides,  and  rich  cloths  of  haudkm  of  : 
divers  colours."  ' 

Tappet  -  motion,  the  apparatus  for  ' 
working  the  steam-valve  of  a  Cor-  ' 
nish  steam  engine,  consisting  of' 
levers  connected  to  the  valves, ' 
moved  at  proper  intervals  b  jr  tap-  ■ 
pets  or  projecting  pieces  fixed  on  a  ; 
rod  connected  to  the  beam 

Tartan,  a  small  coasting  vessel  of  the 
Mediterranean,  with  one  mast,  a 
bowsprit)  and  a  lateen  sail 

Tnmif  a  sea  term  signifying  too  high 
or  tall,  as  the  mast  of  a  ship 


TEA 


TEMPERATURE. 


TEM 


Teak  wood  is  a  native  of  the  moun- 
tainous parts  of  the  Malabar  coast, 
of  Java,  Ceylon,  &c  It  grows 
quickly,  straight,  and  lofty.  The 
wood  is  light  and  porous,  and  easily 
worked;  but  it  is  nevertheless 
strong  and  durable.  It  is  soon 
seasoned,  and,  being  oily,  does  not 
injure  iron,  and  shrinks  but  little 
in  width.  Its  colour  is  light  brown, 
and  it  is  esteemed  a  most  valuable 
timber  in  India  for  ship-building 
and  house-carpentry.  It  has  many 
localities.  In  twenty-five  years  the 
teak  attains  the  size  of  2  feet  dia- 
meter, and  is  considered  service- 
able timber,  but  it  requires  100 
years  to  arrive  at  maturity. 

Teffula,  a  roofing  tile:  roofing  tiles 
were  made  by  the  Greeks  like 
bricks  of  baked  clay 

Telamones  or  Atlante$t  statues  of  men 
employed  in  columns  or  pilasters 
in  classical  architecture 

Tel^t^h,  a  machine  adapted  for 
communicating  intelligence  rapidly 
at  a  considerable  distimce  by  means 
of  various  signals  previously  ar- 
ranged 

Teleacopct  a  large  optical  instrument 
for  observing  the  celestial  bodies, 
whereby  several  new  phenomena 
have  been  discovered,  and  great 
improvements  made  in  astronomy: 
by  properly  grinding  and  placing 
the  lenses  or  glasses  in  a  tube  or 
pipe  of  various  lengths,  objects  at 
a  great  distance  are  brought  nearer 
to  the  eye,  and  much  more  distinctly 
seen  than  by  the  natural  eye :  there 
are  various  kinds  of  telescopes, 
which  are  called  by  distinct  names 

Temperature.  The  temperature  of 
^he  surrounding  atmosphere  exer- 
cises a  powerful  influence  in  the 
preservation  or  decomposition  of 
all  organic  bodies  exposed  to  it. 
Thus,  while  a  high  temperature 
hastens  the  decay  of  animal  and 
vegetable  matter,  it  is  completely 
arrested  at  or  near  the  freezing- 
potnt  of  water.  Hence,  by  artificial 
means,  these  substances  may  be 
preserved  for  a  length  of  tune.    A 


citizen  of  the  United  States  has 
thus  accomplished  the  means  of 
preserving  meats,  fruits,  &c.     A 
large  apartment  is  built  under  the 
ground,   the  sides  of  which  are 
lined  with  a  double  wall  containing 
saw-dust :  over  the  ceiling  is  a  room 
filled  with  ice,  which,  gradually 
melting,  filters  through  the  saw- 
dust, and  keeps  the  temperature  of 
the  underground  apartment  always 
at  34^  Fahr.,  or  two  degrees  above 
the  freezing-point.    In  this  apart- 
ment,   lemons,    oranges,    apples, 
strawberries,  flowers,  &c.,  are  pre- 
served with  complete  freshness  for 
any  length  of  time  that  may  be  re- 
quired. 
Temperature  of  different  Thermome- 
tera,   A  thermometer  is  an  instru- 
ment for  measuring  the  tempera- 
ture of  bodies,  or  the  degree  of 
intensity  of  their  sensible  heat.  In 
Europe  there  are  three  different 
kinds  of  thermometers :  1.  Fahren- 
heit's, which  is  used  chiefly  in  Great 
Britain,  Holland,  and  North  Ame- 
rica, the  freezing-point  on  which 
isat32^andtheboiUng-point212^  ^ 

2.  Reaumur*s,which  was  that  chiefly  I 
used  in  France  before  the  revolu- 
tion,  and  now  generally  used  in 
Spain,  and  in  some  other  conti- 
nental states :  the  freezing-point,  or 
zero,is  0°,  and  the  boiling-point  80^ 

3.  The  Celsius,  or  Centigrade  ther- 
mometer, now  almost  universally 
used  throughout  France,  and  in  the 
northern  and  middle  kingdoms  of 
Europe :  the  zero  or  freezing-point 
is  0%  and  boiling-point  100°. 
Hence,  to  reduce  degrees  of  tem- 
perature of  the  centigrade  thermo- 
meter, and  of  that  of  Reaumur,  to 
degrees  of  Fahrenheit's  scale,  and 
conversely, —  Rule  I.  Multiply  the 
centigrade  degrees  by  9,  and  divide 
the  product  by  5 ;  or  multiply  the 
degrees  of  Reaumur  by  9,  and  divide 
the  product  by  4 ;  then  add  32  to  the 
quotient  in  either  case,  and  the  sum 
is  the  degrees  of  temperature  on 
Fahrenheit's  scale.  Rule  II.  From 
the  number  of  degrees  on  Fahrcn- 


TEM 


TEMPERATURE. 


TEM 


1 


heit's  scale  subtract  32,  multiply 
the  remainder  by  5  for  centigrade 
degrees,  or  by  5  for  those  of  Reau- 
mur's scale,  and  the  product  in 
either  case,  being  divided  by  9,  will 
give  the  temperature  required. 

In  all  inquiries  into  the  effects 
of  heat,  it  is  necessary  to  attend  to 
thefollowing  rules  respectingthe  ap- 
plication  of  the  term  Temperature : 

Istly.  If  a  body  subject  to  no 
pressure,  or  to  a  constant  pressure, 
have  at  two  different  times  the 
same  bulk,  it  is  said  on  both  occa- 
sions to  have  the  same  tempera- 
ture. 

2ndly.  Two  bodies  are  said  to 
have  the  same  temperature,  if,  he- 
ir g  kept  in  contact,  the  tempera- 
ture of  either  remains  unaltered  by 
the  action  of  the  other. 

3rdly.  When  bodies  of  different 
temperatures  are  in  contact,  the 
temperature  of  the  hotter  body  de- 
creases, and  that  of  the  colder  in- 
creases,  till  they  become  equal. 

4thly.  If  the  bodies  be  equal  in 
mass  or  in  weight,  and  of  the  same 
substance,  the  increase  of  tempe- 
rature in  one  will  be  equal  to  its 
decrease  in  the  other. 

Hence  it  will  be  seen  that  dif- 
ferences of  temperature  are  mea- 
surable and  comparable  with  each 
other,  quite  independently  of  any 
change  of  bulk;  that  is,  without 
using  the  latter  as  a  measure  of 
temperature,  but  only  as  a  test  by 
which  change  of  temperature  is  de- 
tected. 

In  this  way  it  has  been  dis- 
covered that  the  same  increment 
(not  equal  increments,  as  from  40^ 
to  50°,  and  from  50°  to  60°)  of 
temperature  causes  all  masses  of 
the  same  substance  to  expand  in 
the  same  ratio  to  their  whole  for- 
mer bulk ;  but  this  is  by  no  means 
the  case  with  different  substances, 
as  is  obvious  by  looking  at  a  com- 
mon thermometer,  an  instrument 
for  measuring  changes  in  the  bulk 
of  a  mass  of  liquid  contained  in  a 
glass  vessel,  of  such  a  form  that 

452 


changes,  very  small  coihpared  with 
the  whole  bulk  of  the  liquid,  may 
cause  its  surface  to  rise  and  fail 
through  a  considerable  space. 
But  this  could  not  be  done  if  the 
glass  and  the  measurio^  scale,  in 
undergoing  the  same  changes  of 
temperature  as  the  liquid,  expe- 
rienced also  the  same  change  of 
bulk;  for,  if  such  were  the  case, 
the  liquid  surface  would  alw^ays  re- 
main opposite  the  same  degree  on 
the  scfide.  The  value  of  this  sim- 
ple instrument,  therefore,  depends 
on  the  fact,  that  liquids  are  more 
expansible  than  solids. 

But  it  will  further  be  seen  that 
the  ratio  of  the  change  of  bulk  to 
the  whole  bulk  is  different  for 
every  different  substance,  when  the 
change  of  temperature  is  the  same 
in  all.  It  is  necessary,  however, 
to  guard  against  a  very  common 
error  respecting  the  relation  be- 
tween temperatures  and  the  num- 
bers by  which  they  are  represented; 
namely,  the  degrees  of  the  ther- 
mometer. 

Although  the  differences  of  tem- 
peratures are  kifown  and  compara- 
ble quantities,  yet  their  ratios  are 
not  so :  they  can  be  compared  by 
addition  and  subtraction,  but  not 
by  multiplication  or  division.     We 
cannot  say,  "This  temperature  is 
so  many  times  that,''  because  we 
do  not  know  the  real  zero  of  tem- 
perature ;  that  is,  we  do  not  know 
what  is  the  smallest  bulk  into  which  | 
a  given  body  is  capable  of  being  i 
condensed  by  cold.    We  cannot,  | 
therefore,  say,  "  This  body  exceeds  ; 
its  minimum  bulk  by  twice  as  much  • 
as  that  body  exceeds  its  minimum 
bulk ;"  or,  in  other  words,  "  This  | 
body  is  twice  as  hot  as  that ;"  for  i 
although  the  temperature  of  one 
body  may  be  80°  and  that  of  an- 
other 40°»  these  numbers  are  only 
reckoned  from  an  arbitrary  zero  or 
starting-point,  adopted  because  the 
real  zero  is  unknown.     But  al- 
though we  cannot  say  that  A  has 
twice  the  temperature  of  B,  we  can 


TEM 


TEMPERING  OF  STEEL. 


TEM 


say  that  the  temperature  of  A  ex- 
ceeds that  of  B  by  twice  as  much' 
as  the  temperature  of  C  exceeds 
that  of  D. 

The  first  question,  then^  regard- 
ing the  relation  of  expansion  to 
temperation,  is — "  Do  equal  dif- 
ferences of  temperature  cause  the 
bulk  of  a  body  to  vary  by  equal 
differences?''     This  question  had 
to  be  settled  before  it  could  be 
known  whether  the  common  ther- 
mometer (the  scale  of  which  is 
divided  into  equal  parts)  measured 
differences    of   temperature    cor- 
rectly.     For   this    purpose,    Dr. 
Brooke  Taylor  heated  two  equal 
weights  of  water,  one  to  200^  and 
the  other  to  100°,  and,  on  mingling 
them  together,  he  found  them  to 
indicate    exactly    IdO** ;    thereby 
showing  that  equal  «differences  of 
temperature  cause  equal  differences 
in  the  expansion  of  mercury ;  or  ra- 
ther in  the  excess  of  its  expansion 
over  that  of  glass,  which  is  clearly 
all  that  the  thermometer  can  mea- 
sure.   More  accurate  experiments, 
however,  have  shown  that  this  rule 
does  not  exactly  apply  to  any  solid 
or  liquid,  but  only  to  gases.  When 
equal  masses  of  the  same  liquid,  at 
different  temperatures,  are  mixed, 
their  combined  bulk  becomes  a 
very  little  diminished.     Liquids, 
therefore,  instead  of  expanding  by 
equal  increments  of  space  for  equid 
increments  of  temperature,  expand 
faster  as  the  temperature  increases 
equably;  and  it  appears  that  the 
correctness  of  the  mercurial  ther- 
mometer observed  by  Dr.  Brooke 
Taylor  was  the  result  of  a  fortunate 
coincidence,  by  which  the  expan- 
sion of  the  glass,  which  is  very 
small  compared  with  that  of  the 
mercury,  exactly  compensated  the 
increasing  rate  of  the  latter.  This, 
however,  would  not  be  the  case 
with    thermometers    constructed 
with  other  liquids,  for  their  rates 
of  expansion  increase  more  rapidly 
than   that   of   mercury.     Hence 
spirit  thermometers  cannot  be  de- 

453  V  5 


pended  on  for  temperatures  above 
the  atmospheric  range  (or  above 
100°). 

Temperinfff  in  metallurgy,  the  pre- 
paring of  steel  or  iron,  so  as  to 
render  them  more  compact,  hard, 
and  firm,  or  the  reverse,  more  soft 
and  pliant 

Tempering  of  steel  Nearly  every  kind 
of  steel  requires  a  particular  degree 
of  heat  to  impart  to  it  the  greatest 
hardness  of  which  it  is  susceptible. 
If  heated,  and  suddenly  cooled  be- 
low that  degree,  it  becomes  as  soft 
as  iron :  if  heated  beyond  that  de- 
gree, it  becomes  very  hard,  though 
brittle ;  and  its  brittleness  is  an  in- 
dication of  the  degree  of  its  heat, 
when  cooled  off»  These  are  the 
reasons  why,  in  hardening  steel,  it 
is  generally  overheated,  and  then 
tempered.  To  hit  the  exact  heat 
required  is  a  matter  of  extreme 
delicacy. 

The  hardening  of  steel  may  be 
Jierfectly  understood  by  studying 
its  nature.  In  endeavouring  to 
arrive  at  the  temperature  best 
adapted  to  a  particular  case — a 
case,  for  instance,  in  which  a 
strange  kind  of  steel  has  to  be  dealt 
with — a  practical  test,  namely, 
drawing  the  bar  into  a  tapered 
point  or  chisel,  is  applied.  This 
wedge-shaped  chisel  will,  of  course, 
be  more  warm  towards  the  point 
than  at  the  thick  part ;  and  it  is 
evident  that  this  part  will,  when 
cooled  in  the  same  cold  medium, 
be  harder  than  the  thick  part.  By 
breaking,  and  continuing  to  break 
off,  the  point,  the  difference  of 
grain  will  show  the  different  tem- 
peratures which  have  been  applied. 
The  finest  and  closest  grained  is 
considered  the  best.  In  hardening 
such  steel,  it  is  heated  with  a 
due  relation  to  the  degree  of  the 
test  heat.  Though  this  manipu- 
lation is  very  imperfect,  careful  and 
intelligent  workmen  are  generally 
quite  successful  in  arriving  at  a 
knowledge  of  what  degree  is  fa- 
vourable.   The  degree  of  hardness 


TEM 


TEMPLE. 


TEM 


depends,  in  tome  measure,  upon 
the  heat  of  the  steel,  but  mainly 
upon  the  difference  between  the 
heat  of  the  steel  and  that  of  the 
water  or  medium  in  which  it  is 
cooled.  The  coldest  water  will 
make  the  hardest  steel.  Mercury 
is  better  adapted  to  harden  steel 
than  water;  so  is  water,  acidu- 
lated with  any  kind  of  acid,  or  con- 
taining any  kind  of  salt  in  solution. 
The  process  of  hardening  is  per- 
formed with  due  relation  to  the 
quality  of  the  steel  and  the  pur- 
poses for  which  it  is  designed.  In 
most  instances,  the  hardening  is 
eflfeeted  in  water  or  brine.  Saw- 
blades  are  thus  hardened,  after 
being  heated  la  melted  lead ;  and 
sabres  are  heated  in  a  choked  fire 
of  charcoal,  and  then  swung  rapidly 
through  the  air.  Mint  stamps  are 
hardened  in  oil  or  metallic  com- 
positions. The  common  method 
of  procedure  in  hardening  is  this : 
The  steel  is  overheated,  cooled  in 
cold  water,  and  then  annealed  or 
tempered  by  being  so  hi  re-heated 
that  oil  and  tallow  will  bum  on  its 
surface ;  or  the  surface  is  ground 
and  polished,  and  the  steel  re- 
heated until  it  assumes  a  certain 
colour.  The  gradations  of  colour 
consecutively  follow :  a  light  straw 
yellow,  violet,  blue,  and  finally  gray 
or  Uack,  when  the  steel  again  be- 
comes as  soft  as  though  it  had 
never  been  hardened. 

Ten^la,  certain  timbers  introduced 
in  the  roofs  of  temples ;  they  were 
placed  upon  the  canterii,  or  prin. 
dpal  rafters,  extending  the  whole 
length  of  the  temple  from  one  fas- 
tigium  to  the  other,  corresponding 
in  situation  and  use  with  the  com- 
mon purlins 

Temple,  a  building  set  apart  for  the 
services  of  religious  worship,  espe- 
cially the  Jewish,  and  those  which 
were  dedicated  to  the  heathen 
deities:  the  name  is  not  unfre- 
quently  applied  to  Christian  sanc- 
tuaries, for  example,  the  Temple 
church,  London.    The  first  Jewish 


temple,  buUt  by    Solomon,   was 
erected  at  vast  expense ;  the  gold 
and  silver  only*  which  was  pro- 
vided for  the  purpose,  amounting, 
it  is  said,  to  an  almost  incredible 
sum.     It  was  built  much  in  the 
same  form  as  the  Tabernacle,  only 
every  way  of  larger   dimensions. 
It  was  surrounded,  except  the  front 
or  east  end,  with  three  stories  of 
chambers,  each  5  cubits   square, 
which  reached  to  half  the  height 
of  the  temple,  and  the  front  was 
graced  with  a  magnificent  portico, 
which  rose  to  the  height  of  120 
cubits,  so  that  the  shape  of  the 
whole  was  not  unlike  some  churches 
which  have  a  lofty  tower  in  the 
front  and  a  low  aisle  running  along 
each  side  of  the  building.     This 
temple  was  plundered  by  Nebu- 
chadnezuc,  King  of  Babylon,  and 
the  building  itself  destroyed,  ac- 
cording to  Josephus,  after  it  had 
stood  between  400  and  500  years. 
The  second  temple,  erected  after 
the   Jews'   return  from  Babylon, 
stood  for  500  years,  when  Herod 
rebuilt  it  in  a  style  of  great  mag- 
nificence.   Tacitus,  the  Roman  his-  - 
torian,  calls  it  a  temple  of  immense  I 
opulence.  This  magnificent  temple  I 
was  at  length  destroyed  by  the  I 
Romans  in  the  same  month  and  ' 
on  the  same  day  of  the  month  as  { 
Solomon's  temple  was  destroyed  by  ' 
the  Babylonians.    Of  the  temples  ' 
of  classic  history,  the  most  eele-  , 
brated  are  those  of  Greece,  con-  > 
sisting  of  the  Parthenon,  built  onder 
Pericles,  theErechthettm,andothers 
noticed  in  Stuart's  'Antiquities,'  | 
and  in  the  works  of  the  Dilettanti , 
Society,  of  Cockerell,  Donaldson, ; 
&c.:  oif  Rome,  the  chief  temples  ; 
were,   the  Gapitol»  the  Pantheon  , 
(built  by  Agrippa),  the  temple  of 
Apollo,  the  temple  of  Janus,  and 
others  interestingly  described  by  , 
Degodetz,  and  also  by  Taylor  and  | 
Cresy.  ] 

Templeif  a  gauge  cut  out  of  a  thin  ^ 
fHCce  of  metal  to  the  form  of  the 
work  to  be  executed 


454 


T£M 


TETRASTYLE. 


THA 


Temphtm  (Latin),  a  temple.  Tem- 
ples appear  to  have  existed  in 
Greece  from  the  earliest  times; 
they  were  separated  from  the  pro- 
fane land  around  them,  and  the  en- 
trances were  much  decorated  as 
architecture  advanced. 

Tenacity,  that  quality  of  bodies  by 
which  they  resist  tension  or  tear- 
ing asunder 

Tender,  the  carriage  which  is  attached 
to  a  locomotive  engine,  and  con- 
tains the  supply  of  water  and  coke 

Tenon,  in  carpentry,  the  square  end 
of  a  piece  of  wood  or  metal  dimin- 
ished by  one-third  of  its  thickness, 
to  be  received  into  a  hole  in  an- 
other  piece,  called  the  mortise,  for 
the  jointing  or  fastening  of  the  two 
together 

Tension,  a  force  pulling  or  stretching 
a  body,  as  a  rod.  Animals  sustain 
and  move  themselves  by  the  ten- 
sion  of  their  muscles  and  nerves. 
A  chord,  or  string,  gives  an  acuter 
or  deeper  sound  as  it  is  in  a  greater 
or  less  degree  of  tension,  that  is, 
more  or  less  stretched  or  tightened. 

Tension^rod,  an  iron  rod  applied  to 
strengthen  timber  or  metal  framing, 
roofs,  &c.,  by  its  tensile  resistance 

Term,  a  piece  of  carved  work  placed 
under  each  end  of  the  taffrail  of 
a  ship,  at  the  side  timbers  of  the 
stern,  and  extended  down  as  low 
as  the  foot-rail  of  the  balcony 

Terra  cotta,  in  the  arts,  baked  earth, 
bricks,  tiles,  &c. 

Terra  di  Sienna,  or  JRaw  Sienna 
Earth,  a  ferruginous  native  pig- 
ment, which  appears  to  be.  an 
iron  ore,  and  which  may  be  con- 
sidered as  a  crude  natural  yellow 
lake,  firm  in  substance,  of  a  glossy 
fracture,  and  very  absorbent.  It  is 
in  many  respects  a  valuable  pig- 
ment, of  rather  an  impure  yeUow 
colour,  but  has  more  body  and 
transparency  than  the  ochres ;  and 
being  little  liable  to  change  by  the 
action  <^  either  light,  time,  or  im- 
pure au:,  it  may  be  safely  used,  ac- 
cording to  its  powers,  either  in  oil 
or  water,  and  in  all  the  modes  of 

455 


practice.  By  burning,  it  becomes 
deeper  orange,  and  more  trans- 
parent  and  drying. 

Terre-verte,  an  ochre  of  a  bluish- 
green  colour;   in  substance  mol  I 
derately  hard,  and  smooth  in  tex-  I 
ture.    It  ia  variously  a  bluish  or  / 
gray  coaly  clay,  combined  with  / 
yellow  oxide  of  iron,  or  yeUow  / 
ochre.    Although  not  a  bright,  it 
IS  a  very  durable  pigment,  being 
unaffected  by  strong  light  and  im- 
pure air,  and  combining  with  other 
colours  without  injury.    It  has  not 
much  body,  is  8emi.tran8parent,and 
dries  well  in  oil.  There  are  varieties 
of  this  pigment;   but  the  green 
earths  which  have  copper  for  their 
colouring  matter  are,  though  ge- 
nerally of  brighter  colouis,  inferior 
in  their  other  qualities,  and  are  not 
true  terre-vertes. 

Tesuelated,  in  the  arts,  variegated  by 
squares ;  exemplified  in  the  beau- 
tiful pavements  of  the  ancients 

Tessera,  small  cubical  pieces  of  brick, 
stone,  or  composition,  forming  part 
of  an  ancient  Roman  mosaic  or 
tesselated  pavement 

Testaceous,  consisting  of  shells ;  made 
of  baked  earth,  or  of  tiles  or  bricks 

Tetragon,  a  quadrangle,  or  a  figure 
having  four  angles 

Tetrahedron,  in  geometry,  one  of  the 
five  regular  bodies  of  solids  com- 
prehended under  four  equilateral 
and  equal  triangles.  It  may  be 
conceived  as  a  lingular  pyramid 
of  four  equal  faces. 

Tetrants,  the  four  equal  parts  into 
which  the  area  of  a  circle  is  di- 
vided  by  two  diameters  drawn  at 
right  angles  to  each  other 

Tetrastyle,  a  portico,  &c.  consisting  of 
four  columns.  A  cavaedium  was 
called  tetrastyle  when  the  beams 
of  the  compluvium  were  supported 
by  columns  placed  over  against  the 
four  angles  of  a  court. 

Thatch,  straw  or  reeds  employed  for 
covering  the  roofs  of  buildings; 
particularly  used  for  cottages 

Thoughts  or  Thwarts,  in  navigation, 
the  benches  or  seats  in  a  boat 


THE 


THEORY. 


THE 


TheatreSf  edifices  of  various  but  prin- 
cipally of  large  dimensions,  for 
dramatic  exhibitions 

Theatrumt  a  theatre.  The  Athenians, 
before  the  time  of  iEschylos,  had 
only  a  wooden  scaffolding  on  which 
their  dramas  were  performed.  It 
was  merely  erected  for  the  time  of 
the  Dionysiac  festival,  and  was 
afterwards  pulled  down. 

Theodolite^  in  surveying,  a  mathe- 
matical instrument  for  measuring 
heights  and  distances.  (See  Hea- 
ther's work  on  Instruments.) 

Theory  i  a  doctrine  which  terminates 
in  the  sole  speculation  or  con- 
sideration of  its  object,  vnthout  any 
view  to  the  practice  or  application 
of  it.  To  be  learned  is  an  art,  and 
the  theory  is  sufficient ;  to  be  mas- 
ter of  it,  both  the  theory  and  prac- 
tice are  requisite.  Machines  often 
promise  very  well  in  theory,  but  fail 
in  practice.  A  remarkable  circum- 
stance may  be  instanced  of  a  gen- 
tleman of  British  North  America 
selling  his  estate  and  leaving  his 
home  to  give  practical  effect  to  a 
theory  he  had,  as  he  considered, 
beautifully  worked  out  in  figures, 
for  an  important  improvement  in 
steam  machinery.  His  theory,  how- 
ever, wholly  failed  on  its  first  ap- 
plication in  practice. 

Theory,  mathematical^  the  algebraic 
elucidation  of  the  principles  of  any 
physical  system,  where  assumptions 
are  made,  in  the  absence  of  positive 
data:  the  calculated  results  are 
expressed  in  formulae,  which  are 
easily  convertible  into  arithmetical 
rules.  Among  others,  the  *  Theory 
of  the  Steam  Engine,'  by  the  Count 
de  Pambour,  has  been  found  to 
be  most  useful  for  practice;  and 
the  following  is  an  explanation  of 
his  mathematical  investigation,  de- 
signed for  persons  not  familiar  with 
the  algebraic  signs,  and  intended 
to  render  clear  and  easy  the  use  of 
the  formula  contained  in  the  above- 
mentioned  work,  and  which  may 
be  said  to  have  reference  to  all 
mathematical  works. 

456  — 


Among  persons  engaged  in  the 
construction  or  working  of  steam 
engines,  there  is  a  great  number  to 
whom  the  algebraic  terms  are  little 
familiar,  and  who  usually  give  up  i 
the  rea<Mng  of  a  book  as  soon  as  they . 
perceive  that  it  steps  beyond  the  ^ 
simple  notions  of  arithmetic  When  > 
it  is  intended  to  make  a  wozk  pro-  j 
fitable  to  those  persons,  the  usual 
practice  is  to  annex  to  each  of  the  - 
definitive  formulae  an  explanatiou,  > 
in  full  words,  of  the  arithmetical 
operations  wbich  it  represents. 

The  want  of  such  explanation 
may  be  very  advantageously  sup*  { 
plied,  by  giving  the  signification  of  { 
every  sign  employed  in  theformulx; ; 
by  explaining  what  are  the  arith-  > 
metical  operations  represented  by ' 
those  signs.    With  the  help  of  a ' 
very  few  rules  on  this  subject,  per- 
sons will  find  that  the  reading  of' 
the  formulae  is  quite  as  easy  in 
algebraic   signs    as   if  they  were 
written  in  words ;  since,  after  all, ; 
it  is  but  an  abridged  way  of  ex- 
pressing the    same    things,  and, 
moreover,  the  operations  to  be  per- 
formed, in  order  to  attain  the  result, 
are  much  more  clear,  and  more 
easy  for  the  mind  to  seize.   Again, , 
a  perfect  acquaintance  with  the' 
signification  of  the  signs  in  common 
use  can  require  but  a  few  hours  of 
attention,  and  when  once  a  person  I 
shall  have  made  himself  master  of , 
them,  he  will  be  capable  of  reading 
the  formulae  of  all  works. 

A,  B, .  •  •  •  0,  6, . .  • .  »,  991,  n, .  •  I 
. .  a,  iS, . . . .  &c.     The  letters  are  | 
an  abridged  manner  of  writing  the  i 
numbers  which  those  letters  repre- 
sent.   Thus,  when  the  stroke  of 
the  piston  has  been  measured,  and 
found,for  instance, to  be  I7i  inches, 
it  would  be  inconvenient  to  write 
in  all  the  formulae  the  number  17i 
But  if  the  length  of  stroke,  what- 
ever it  might  be,  has  been  repre- 
sented by  a  letter,  as  /,  for  in- 
stance, then,  every  time  the  letter 
/  occurs,  th^  needs  only  to  re- , 
collect  that  it  represents  the  nnm- 


THE 


THEORY  (MATHEMATICAL)  EXPLAINED. 


THE 


ber  I7i»  and  peiforming  ynth  that 
number  the  operations  indicated 
in  the  formnls,  relative  to  the 
letter  I,  the  result  sought  will  be 
attained. 

=  . . . .  This  sign  signifies  equal 
to;  it  expresses  that  a  quantity 
sought  is  equal  to  the  number  re- 
sulting from  certain  operations 
performed  on  other  quantities 
known.  Thus,  for  instance,  if  we 
find  the  expression 

V  =  60«T, 

this  will  signify  that  the  quantity 
y  is  equal  to  60  times  the  quantity 
V,  Consequently,  if  we  know  be- 
sides that  the  letter  v  represents 
the  number  100,  it  will  follow  that 
the  unknown  quantity  V  will  have 
for  its  value  60  times  100,  or  6000. 
+  . . . .  This  sign  signifies  phi8 
(more).  Placed  between  two  let- 
ters or  two  numbers,  it  indicates 
that  they  are  to  be  added  together. 
If,  for  instance,  there  be  in  a  for- 
mula an  expression  of  the  form 

1  +  5, 

it  means  that  to  the  number  1 
must  be  added  the  number  5.  If, 
then,  we  know  besides  that  the 
letter  9  represents  the  number  *14, 
it  follows  that  the  expression  1  +  9 
will  have  for  its  value 

1  +  5  =  1  +  -14  =»  1-14. 

—  . . . .  This  sign  indicates  minus 
(less).  Thus,  when  an  expression 
occurs  of  the  form 

p  -/-  2118, 

the  expression  amounts  to  saying 
that,  from  the  number  P  the  num- 
bers/and 2118  are  to  be  suc- 
cessively subtracted.  If,  then,  we 
know  that  the  letter  P  represents 
the  number  9360,  and  that  the 
letter /represents  the  number  144, 
the  expression  will  have  for  its 
value 

P-/- 2118  =9360 -144 
-2118=7098. 

457 


X  . . . .  This  sign  expresses  mul- 
tipUed  by.    Thus  the  expression 

a  X  V 

indicates  that  the  two  numbers 
represented  by  the  letters  a  and  v 
are  to  be  multiplied  one  by  the 
other;  and  the  product  of  that 
multiplication  will  be  the  quantity 
expressed  here  by  a  x  v.  This 
multiplication  to  be  performed  is 
equally  expressed  by  a  point  be- 
tween the  two  letters,  or  by  writing 
the  two  letters  simply  together 
without  any  sign  interposed;  so 
that  the  expressions 


a  X  V 


.  .   •  a     , 


a .  V 


a  t. 


amount  to  the  same,  all  three  ex- 
pressing the  result  of  the  mul- 
tiplication of  the  numbers  repre- 
sented by  a  and  v.  If,  for  instance, 
an  expression  occur  like  the  fol- 
lowing, 

arv, 

and  it  be  known  that  the  letter  a 
expresses  the  number  1'57,  the 
letter  r  the  number  2640*96,  and 
the  letter  v  the  number  300,  the 
expression  arv  will  have  the 
value 

arv  =  1-57  x  2640-96  x  300 
=  1243800. 

-s- . . . .  This  sign  denotes  divided 
by.    Thus  the  expression 

S 
a 

expresses  S  divided  by  a,  or  the 

quotient  resulting  from  the  division 

of  the  number  expressed  by  S,  by 

the  number  expressed  by  a. 

For  instance,  if  we  have  S  =  '67 

and  a  =  1*57,  it  is  plain  that  the 
§ 

term—  wUl  have  for  its  value 
a 


S 
a 


•67 


1-57 


=  -4268. 


A  fraction  may  have  its  nume- 
rator or  its  denominator  composed 


THB 


THBORT  (MATHEMATICAL)  EXPLAINED. 


THE 


of  KTeral  numben,  oa  which  di- 
vers operations  are  incUcated.  In 
that  case,  those  operations  must 
first  be  performed,  so  as  to  reduce 
the  numerator  and  the  denomina- 
tor to  single  numbers,  before  per- 
forming the  division  of  the  one  by 
the  other,  as  has  just  been  said. 

If,  for  example,  we  have  the 
fraction 

10000 


1-492  +  -002415  P 

and  know  besides  that  the  letter  P 
represents  the  number  9360;  we 
must  first  perform  the  multiplica- 
tion of  the  number  9360  by  the 
number  -002415,  and  then  add  to 
the  product  the  number  1*492. 
The  result  will  be  the  number 
24-0964,  which  will  therefore  re- 
present  the  denominator  of  the 
fraction.  The  fraction  may  then 
be  written  under  the  form 

10000 


240964 


and  consequently  it  is  reduced  to 
the  simple  indication  of  the  quotient 
of  two  numbers,  as  in  the  preceding 
case. 

If  two  fractions  occur,  separated 
by  the  sign  of  addition,  or  that  of 
subtraction,  or  that  of  multiplica- 
tion, the  meaning  is  that,  after 
having  sought  separately  the  quo- 
tient indicated  by  each  of  those 
fractions,  they  are  either  to  be 
added  together,  or  one  deducted 
frpm  the  other,  or  one  multiplied 
by  the  other.  Thus,  the  expression 


S 
a 


10000 


1-492  + -002415  P 


signifies  that,  after  having  sought 
the  quotient  indicated  by  each  of 
the  two  fractions,  the  first  of  these 
quotients  is  to  be  multiplied  by 
the  second.  Supposing  the  letters 
to  be  of  the  same  numerical  value 
as  in  the  preceding  cases,  the  pro- 
duct of  the  two  fractions  would 
here  be  the  definitive  number  176. 

458  "  ~" 


It  would  be  the  same  if  we 
were  to  find  one  fraction  divided 
by  another.  Each  of  them  should 
be  first  reduced  to  a  aing^e  number 
by  finding  the  quotient  they  repre- 
sent, and  then  the  one  of  these 
quotients  divided  by  the  other. 

()or[]  or  {}....  Paren- 

theses  indicate  that  the  difiTerent 
quantities  contained  between  them 
are  to  be  reduced  to  a  single  num- 
ber before  performing  the  other 
operations  indicated  in  the  formuls. 
Thus,  for  instance,  if  we  find  in 
a  formula  the  expression 

(1  +  «)«» 

this  means,  that  it  is  the  expression 
(1+5)  entire,  which  is  to  be 
multiplied  by  v»  The  sum  then  of 
1  +  8  is  first  to  be  formed,  and 
afterwards  multiplied  by  the  num- 
ber V ;  whereas,  had  we  only 

1  +  8», 

this  would  mean  that  the  product 
8  V  is  first  to  be  formed,  and  after- 
wards the  number  1  added  to  it. 

There  may  occur  several  paren- 
theses comprised  one  within  the 
other,  but  their  signification  is 
always  the  same.    The  expression 

•002415  [(1  +  «)r+/] 

denotes  that  the  sum  of  1  -f  8  is 
to  be  formed  first,  this  to  be  mul- 
tiplied by  r,  and  the  product  added 
to  the  quantity/,  which  gives  the 
number  represented  by  the  outer 
parenthesis ;  and  finally,  that  this 
number  is  to  be  multiplied  by 
•002415. 

Lastly,  when  there  occofs  in 
the  formulae  a  letter  with  a  small 
figure  or  exponent  above  it,  it  is  j 
the  same  thing  as  writing  that 
letter  as  many  times  successively  as 
there  are  units  in  the  figure  or  ex- 
ponent. 

For  instance,  the  expression 


is  equivalent  to   the   expression 


'  THE               THEORY  (MATHEBCATICAL)  EXPLAINED.               THE 

V  X  »,  or  9  written  twice;  that  is 
to  say,  it  is  the  product  of  v  by 
itself.    If  then  v  were  known  to  be 
equal  to  300,  the  quantity  repre- 
sented  by  »*  would  be 

V'  :=  300  X  300  =  90000. 

These  short  explanations  are  all 
that  is  necessary,  in  order  to  read 
and  perfectly  understand  aU  prac- 
tical formulae.    Replacing  each  of 
the  signs  that  are  met  with  in  a 
formuhi,  by  the  periphrasis  which 
the  sign  re^nresents,  you  read  the 
formula  such  as  it  ought  to  be  ex- 
pressed ;  and  effecting  the  arithme- 
tical  operations  indicated  by  those 
signs,  you  attain  the  result  sought. 
A  formula  is,  then,  nothing  more 
than  an  abridged  manner  of  writing 
the  series  of  operations  to  be  per- 
formed, in  order  to  amve  at  the 
result  which  we  want  to  obtain. 

We  will  subjom  to  this  explana- 
tion  some  examples,  taken. from 
the  practical    formula    of  high- 
pressure  engines. 

I.  Suppose  we  haye  the  formula 

S                             10000 

indicated  by  the  outer  parenthe- 
sis, viz. 

[(l  +  «)r+/]-3154. 

Now  multiply  this  sum  by  the  num- 
ber '002415,  and  the  product  will 
evidently  be 

•002415 [(1  +  «)  r +/]  »-002415  x 
3154=7-6170. 

Add  to  this  last  result  the  number 
6*6075,  and  you  obtain 

6-6075  +  -002415  [(1  +  5)  r  +/]  = 
6-6075 +  7-6170  =  14-2245. 

This  is  then  the  denominator  of 
the  fraction  which  forms  the  second 
member  of  the  formula.    Perform- 
ing the  division  of  the  number 
10000  by  the  number  just  obtained, 
the  quotient  will  be 

10000 

6-6075  +  -002415  [(1  +  8)  r  +/] 

10000      ^^«  ^, 

-14.2245-^^^'«^- 

On  the  other  hand,  dividing  S 
by  a,  or  the  number  '67  by  the 
number  1-57,  you  have  the  value 

of  the  fraction  -,  viz. 

a     1*57 

Finally,  then,  multiplying  this  lat- 
ter quotient  by  that  obtained  im- 
mediately above,  you  have  defini- 
tively 

S                     10000 

*''"  a' 6-6075  +  •002415[(1  +  5)r +/] 

=•4268  X  703*04  »300. 

Thus  it  is  clear  that  by  effecting 
successively  the  series  of  calcula- 
tions indicated  by  4he  few  signs 
which  are  explained,  and  proceed- 
ing  gradually  from  the  most  simple 
terms  to  the  more  compounded 
ones,  we  arrive  without  difficulty 
at  the  definitive  result. 

We  wfll  give  some  other  exam- 
ples of  tiiese  calculations ;  but,  in- 
stead of  efifeeting  the  operations, 
we  will  merely  express  in  words 

*''"  a'6'6075  +  '002416[(l  +  5)r+/]' 

which  is  intended  to  determine 
the  nnknown  value  of  v ;  and  let 
it  be  supposed  that  we  know,  be- 
sides, that  the  other  letters  com- 
prised in  this  formula  have  the 
following  value : 

S  =  -67 
a  =  1-57 
«  «   14 
r  =  2641 
/  =  144. 

First  form  the  sum  (1  +  5),  indi- 
cated in   the    inner  parenthesis, 
which  will  be 

1  +  5=M4. 

Then  multiply  this  number  by  r,  or 
2641,  and  the  result  will  be 

(1  +  5)  r=l-14  X  2641  =3010. 

Add  to  this/,  or  144,  and  the  sum 
will  consequently  be  the  quantity 

459 


THE 


THEORY  (MATHEMATICAL)  EXPLAINED. 


THE 


the  signification  of  the  formula, 
which  amounts  to  the  same* 
II.  Suppose  we  have  the  fonnula 

S 
fl  r  =  4140750 


(1  +  5)r 
(2736+/); 


a 


this  signifies  that  the  required  value 
of  a  r  will  he  ohtained  hy  perform- 
ing the  following  arithmetical  ope- 
rations : 

Add  1  to  the  number  represented 
by  the  letter  9,  and  multiply  the 
sum  by  the  number  v. 

Then  divide  the  number  S  by 
the  product  thus  obtained ;  multi- 
ply the  quotient  of  this  division  by 
the  number  4140750;  and  write 
apart  this  first  partial  result,  which 
represents  the  first  term  of  the 
formula. 

Add  again  to  unity  the  number 
8,  and  by  that  sum  divide  the 
number  a. 

Similarly  add  io  the  number 
2736  the  number/,  and  multiply 
the  sum  by  the  last  found  quotient ; 
and  set  apart  this  partiid  result, 
which  represents  the  second  term 
of  the  formula. 

Finally,  from  the  first  partial  re- 
sult subtract  the  second,  and  the 
difference  will  be  the  quantity  a  r 
sought. 

Performing  these  difierent  ope- 
rations with  the  values  of  S,  a,  8,  r 
and/,  given  above,  and  supposing 
the  case  wherein  the  letter  v  has 
the  value  v  =  300,  you  find  that 
the  quantity  a  r  will  have  for  its 
definitive  value 

a  r  =  4146* 
III.  If  we  have  the  formula 


10000 


J6- 


6075 +  '0024 15 


[(1  +  5)^+/]].; 


it  will  amount  to  the  following 
arithmetical  explanation : 

To  the  number  1  add  the  num- 
ber 5,  and  multiply  the  sum  by  the 
number  r. 


To  this  product  add  the  number 
/,  and  multiply  the  resulting  sum 
by  the  number  *0024 1 5.  i 

To  the  latter  product  add  the 
number  6*6075,  and  keep  apart  this ' 
partial  result,  which  expresses,  in , 
one  number,  what  proceeds  from ' 
all  the  operations  comprised  in  the  i 
great  parenthesis. 

Then  multiply  the  number  a  by 
the  number  v,  and  divide  the  pro- 
duct by  the  number  10000,  which 
will  give  you  another  partial  result, 
expressing  the  portion  of  the  for- 
mula situated  beyond  the  paien- ' 
thesis. 

Finally,  multiply  the  former  par-  j 
tial  result  by  the  latter,  and  the ' 
definitive  product  will  be  the  re- 1 
quired  value  of  S. 

For  the  values  above  attributed  [ 
to  the  different  letters  contained  in  ' 
the  formula,  the  result  of  the  cal- 1 
culation  will  give  S  =  '67. 

IV.  If  we  have  the  formula 


10000 


a     1-492  + -002415? 

» 

it  will  be  paraphrased  as  follows : 

Multiply  the  number  '0024 15  by 
the  number  P,  and  add  to  the  pro- 
duct the  number  l*4d2 ;  divide  the 
number  10000  by  the  sum  thus 
obtained,  and  write  the  quotient 
apart. 

Then  divide  the  number  S  by 
the  number  a,  which  will  give  a 
second  quotient. 

Finally,  multiply  the  former  quo- 
tient by  the  latter,  and  the  result- 
ing product  will  be  the  required 
value  of  t/. 

With  the  values  already  indi- 
cated for  the  letters,  and,  more- 
over, for  P  »  9360,  the  result  of 
the  preceding  formula  will    give' 
t/=176.  I 

V.  In  fine,  as  a  last  example,  we ' 
will  suppose  the  formula 


«/ 


1  +  a 


(P-/-2118). 


It  plainly  will  signify  as  follows : 
From  the  number  P  deduct  first 


460 


THE 


TIDE. 


TID 


the  number/,  and  again  from  the 
remainder  deduct  the  number  2118. 

Then  to  the  number  1  add  the 
number  9,  and  divide  the  number  a 
by  the  sum  thus  obtained. 

Finally,  multiply  this  quotient 
by  the  difference  before  obtained, 
and  the  definitive  product  thus 
formed  will  be  the  requb^d  value 
of  flr'. 

The  operations  thus  indicated 
would,  for  the  case  wherein  the 
letters  should  have  the  values  al- 
ready given  above,  produce  for  the 
required  value  of  fl  /  the  quantity 
9777. 

Thus  we  see  how  easy  it  is  to 
replace  all  the  formulae  by  their 
expressions  in  words;  and,  conse- 
quently, the  sight  of  algebraic  for- 
mulae ought  in  nowise  to  intimi- 
date persons  unfamiliar  with  al- 
gebra. 
TheothecGf  Monstrance,  or  Remon- 
strance f  sacrament-house  in  the  Ro- 
man Catholic  Church  (the  pix),  the 
receptacle  of  the  consecrated  host, 
made  generally  of  the  most  costly 
materials,  and,'  in  some  cases,  of 
expensive  and  beautiful  design. 
Two  magnificent  examples  are 
given  in  the  *  Divers  Works  of 
Early  Masters/  The  sacrament- 
house  in  the  church  of  St.  Law- 
rence  at  Nuremburg,  date  1510,  is 
64  feet  in  height ;  and  another,  in 
the  church  of  St.  George  at  Lim- 
bourg,  is  upwards  of  30  feet  high. 
Thermometerf  an  instrument  used  for 
measuring  the  degrees  of  heat.  (See 
Temperature  of  different  Thermo- 
meters.) 
Thesaurus  (Greek),  a  treasure-house. 
That  buildings  of  this  description 
were  required,  especially  by  kings 
and  states,  in  the  earliest^period  of 
civilization,  is  self-evident;  and 
tradition  points  to  subterranean 
buildings  in  Greece,  of  unknown 
antiquity  and  of  peculiar  formation, 
as  having  been  erected  during  the 
heroic  period,  for  the  purpose  of 
preserving  precious  metals,  arms, 
and  other  property* 


Thoisj  a  term  used  in  building :  the 
scutcheon  or  knot  in  the'  midst 
of  a  timber  vault ;  also  a  place  in 
temples  where  donaries  (gifts)  were 
hung  up 

Tholobatei  a  cupola,  and  a  base: 
that  part  of  a  building  on  which  a 
cupola  is  placed 

ThohtSt  an  appellation  given  to  all 
buildings  of  a  circular  form.  Vi- 
truvius  uses  it  to  signify  the  roof 
of  a  circular  building. 

Thowlf  a  piece  of  timber  by  which  oars 
are  kept  in  their  places  in  rowing 

Throat,  in  ship-building,  the  hollow 
part  of  knee-timbers. 

Throttle-valve,  a  valve  in  the  steam- 
pipe  of  an  engine,  for  regulating 
the  supply  of  steam  to  the  cylinder. 
In  land  engines  it  is  generally  con- 
nected to  a  governor. 

Thurible,  a  censer  used  in  some  of  the 
services  of  the  Roman  Catholic 
Church,  made  usually  of  metal  in 
the  form  of  a  vase 

Thurl,  a  long  adit  in  a  coal-pit 

Thymele,  in  antiquity,  a  sort  of  altar, 
surrounded  with  steps,  placed  in 
front  of  the  Greek  stage  or  orchestra 

Thyrorea,  the  doors  of  a  Greek  tem- 
ple or  house 

Thyroreum,  a  passage  in  the  hoases 
of  the  Greeks,  at  one  end  of  which 
was  the  entrance  from  abroad,  and 
at  the  other  the  doorway  leading  to 
the  peristyle 

Tiara,  an  ornament  for  the  head,  an- 
ciently used  by  the  Persians 

Tieketings,  the  weekly  sales  of  ores. 
The  adventurers  or  their  agents 
meet  together  at  noon,  and  whilst 
sitting  round  a  table,  each  buyer 
gives  in  his  ticket,  offering  a  cer- 
tain sum  per  ton  for  so  many  tons 
of  ore.  The  tickets  are  then  read 
aloud  by  the  chairman,  and  the 
persons  present  note  the  prices 
offered,  the  lots  or  different  samples 
being  sold  to  the  highest  bidder. 

Tide,  the  natural  fluctuation  of  the 
water  of  the  sea  and  some  rivers, 
whereby  it  increases  and  diminishes 
its  quantity  at  particular  times  and 
places,  the  first  being  called  the 


TID 


TIDE-GAUGE. 


TID 


tide  of  flood,  the  last  the  tide  of 
ebb :  when  the  tide  or  flow  of  water 
runs  against  the  wind,  it  ii  called 
a  windward  tide,  in  which  caae  the 
sea  breaks  most,  and  runs  highest 
Tide-gauffe.  The  meiifc  of  tlus  in- 
Tcntion  is  due  to  Mr.  Meik,  the 
engineer  of  Sunderland  Harbour, 
whose  attention  had  been  for  some 
time  directed  to  the  necessity  of 
haying  conspicuous  tide  -  gauges 
erected  at  all  harbours  and  dodks. 
Intrusted  with  the  management  of 
a  tidal  harbour  with  an  intricate 
and  narrow  channel,  and  where 
frequently  from  150  to  200  sail  of 
Tessels  entered  or  quitted  during  a 
single  tide,  he  perceived  that  the 
number  of  Tessels  that  could  safely 
depart  on  their  outward  voyage 
depended  not  only  on  the  extent 
of  each  tide,  but  also  on  the  know- 
ledge of  those  in  charge  as  to  the 
rate  of  its  flow,  by  which  alone 
they  would  be  enabled  to  form  a 
correct  judgment  as  to  the  suffi- 
ciency of  water  to  enable  the  ves- 
sels  to  proceed  to  sea. 

It  was  evidently  essential  that 
any  tide-gauge  for  this  purpose 
should  be  rendered  intelligible  to 
seamen  of  all  grades,  and  so  situ- 
ated as  to  be  seen  fiom  all  vessels 
in  time  to  allow  the  course  of  those 
outward  bound  to  be  checked, 
should  there  not  be  suflldent  depth 
of  water  to  enable  them  to  pass 
overthe  bar ;  or  should  the  vessel  be 
inward  bound,  and  the  depth  indi- 
cated by  the  gauge  proved  insuf- 
ficient, she  might  be  brought  up, 
or  put  off  again  to  sea;  also  if  the 
vessel  was  at  anchor  in  the  road- 
stead, the  captain  on  board  should 
.be  able  to  know,  from  prominent 
eharacters,the  earhesttime  atwhich 
he  could  take  the  harbour. 

The  first  port  provided  with  a 
regular  set  of  signals  for  this  pur- 
pose  was  that  of  Leith.  The 
signals  used  there  are  very  com- 
plete, and^  with  tiie  assistance  of  a 
careful  man  to  work  the  system 
according  to  the  rise  of  the  tide, 

462 


are  of  essential  benefit  to  the  ship- 
ping. But  few  seamea  pay  sitf- 
ficient  attention  to  matters  of  this 
kind  to  cany  in  tlkeir  memory  the 
exact  depth  of  water  cocreapon^g 
to  the  signals  shown;  and  before 
the  book  is  consulted,  the  vesKl 
may  be  driven  on  the  shore,  or 
stranded  on  the  bar. 

The  signals  at  Leith,  although 
perfect  of  their  kind,  are  used 
only  during  the  day;  while  it  is 
evident  that  night  is  the  time  when 
they  are  most  required  hy  sea- 
men, to  inform  them  of  the  state 
of  the  tide.  By  day  they  genersHj 
have  some  imperfect  mode  of  ar- 
riving at  the  depth  of  water,  by 
observing  when  the  tide  readies 
certain  points  on  shore,  or  coven 
some  known  rocks  at  aea ;  but  at 
night  they  cannot  guess  Bi  the 
tidal  flow  even  by  such  inaccurate 
means,  and  consequently  the  gauge- 
marks  or  figures  should  have  the 
j^perty  of  being  clearly  distin- 
guished at  night  as  well  as  by  day, 
otherwise  little  advantage  vriU  be 
gained,  nor  will  the  loss  of  life  be 
materially  lessened. 

From  these  considerations,  snd 
for  the  purpose  of  exhibiting  the 
advantages  to  be  derived  from 
their  adoption  at  the  different 
ports,  a  self-acting  tidal  gauge, 
combining  the  above-mentioned 
properties,  as  far  as  relates  to  oat- 
ward^bound  ships,  has  been  erected 
at  Sunderland  Harbour,  by  Mr. 
Meik,  in  conjunction  with  Mr.  Wat- 
son, of  Newcastie. 

The  construction  of  the  gauge  is 
as  follows :  A  well,  carefully  boxed 
in,  and  of  similar  depth  to  the  water 
on  the  bar,  is  sunk  below  the 
building  which  contains  the  appa- 
ratus. Within  this  well,  in  an  in- 
terior pipe  (NT  trunk,  and  rising  and 
falling  with  the  tide,  works  a  float 
suspended  by  a  copper  wire  cord, 
which  is  carried  over  a  spiral  cone 
fixed  in  an  upper  story  of  the  build- 
ing.  By  the  simple  arrangement 
of  a  wheel  and  piniim  at  the  oppo- 


TID 


TIE-BEAM. 


TIB 


site  end  of  the  axle  to  which  the 
cone  is  fixed,  a  weh  of  wire  gauze 
works  on  two  rollers  fixed  at  the 
upper  and  lower  ends  of  the  web. 
The  lower  roller  is  regulated  by  the 
movement  of  this  wh^  and  pinion ; 
the  upper  one  by  a  balance-weight 
attached  to  a  copper  wire  cord, 
which  also  passes  over  another 
spiral  cone,  having  at  the  extremity 
of  its  axle  a  second  wheel  and 
pinion  similar  to  the  first.  As  the 
float  rises  and  falls  with  the  tide, 
the  wheels  and  pinions  connected 
with  the  cones,  over  which  the 
cords  of  the  float  and  balance- 
weight  respectively  pass,  move  the 
rollers  on  which  the  gauze  web 
travels.  On  this  web  are  painted 
in  large  figures  the  various  depths 
from  high  to  low  water,  and  as  the 
web  works,  two  fixed  pointers  in- 
dicate the  number  of  feet  and  half- 
feet  on  the  bar  at  any  hour  of  the 
tide. 

The  web  and  the  figures  on  it 
can  be  made  of  any  size,  and  to 
travel  4,  6,  8, 10,  or  any  other  pro- 
portion to  1  of  the  float,  by  regu- 
lating the  size  of  the  wheels  and 
pinions.  By  day  the  figures  on  the 
web  are  shown  white  on  a  black 
ground ;  by  night  they  appear  dis- 
tinctly lighted  up,  the  ground  still 
remaining  dark.  A  white  trans- 
parent varnish  is  used  for  the 
figures,  and  an  opaque  black  for  the 
ground.  The  illumination  by  night 
is  so  steady  and  powerful,  that  the 
figures,  if  made  large  enough,  and 
the  apparatus  fixed  at  a  sufficient 
elevation,  are  visible  at  a  con- 
siderable distance  at  sea,  and  thus 
afford  vessels  the  means  of  knowing 
the  exact  depth  of  water  at  the 
mouth  of  any  harbour  before  enter- 
ing it.  Thu  simple  piece  of  me- 
chanism is  applicable  to  aU  places 
where  the  want  of  a  correct  and 
conspicuous  gauge  has  been  fdt, 
not  only  in  harbours  and  docks, 
but  at  railway  stations,  for  signals 
and  such  like  purposes.  The  ap- 
paratus used  occupies  so  little  space, 

463 


that  it  can  all  be  contained  and 
worked  in  a  colnmn  or  pillar,  with- 
out any  other  building. 

In  the  same  building  is  erected, 
for  the  Commissioners  of  the  River 
Wdr,  a  self-registering  tide-gauge, 
to  which  it  is  also  intended  to  fix 
a  barometer.  The  working  of 
this  self-registering  gauge,  which 
has  for  some  time  been  in  use  at 
a  few  other  ports,  is  as  follows : 
A  pencil  is  fixed  in  a  rack,  which 
registers  the  variations  of  the  tide, 
the  time  of  each  change  being  also 
marked;  and  immediately  under 
which  is  a  cylinder.  On  this  is 
fastened  a  sheet  of  paper,  properly 
ruled  for  the  purpose,  and  of  suf- 
ficient size  to  receive  the  variations 
of  the  tide,  traced  by  the  pencil, 
for  fourteen  days.  The  rack  con- 
taining the  pencil  is  connected  with 
a  wheel,  over  which  a  copper  wire 
cord  passes,  having  attached  to  it  a 
float,  which  works  in  a  well  of 
similar  construction  to  that  already 
described  as  used  for  the  new  tide- 
gauge.  This  float  and  cord  move, 
by  the  action  of  the  tide,  the  rack 
and  the  pencil  in  it,  and  trace  the 
diagram  on  the  paper  below.  A 
dial  on  one  side  of  the  rack  is 
worked  by  the  same  machinery, 
and  points  out  as  a  clock  the  hours 
and  minutes  of  the  day,  and  the 
number  of  feet  from  high  to  low 
water. 

A  time-piece,  furnished  with  a 
strong  minute-hand,  gives  the  re- 
volving movement  to  the  cylinder 
on  which  the  paper  is  rolled,  and 
serves  to  mark  the  time  of  the 
variations  of  the  tide.  The  float 
and  wheel,  in  fact,  are  the  means  of 
showing  the  dep^  of  water ;  the 
time-piece,  the  exact  hour  and  mi- 
nute of  each  change' of  tide. 

i^-ieamf  a  beam  which  acts  as  a 
string  or  tie,  to  hold  together  two 
things  which  have  a  tendency  to 
spread  apart 

Tie-rod,  a  wrought-iron  bar  or  rod 
for  bracing  together  the  frames 
of  steam  engines,  roofs,  &c. 


TIE 


TIN. 


Tn 


Tierce,  a  vessel  containing;  forty- 
two  gallons,  or  the  third  part 
of  a  pipe:  in  the  Romish  Liturgy 
it  is  one  of  the  canonical  hours  for 
prayers,  viz.  eight  in  the  winter, 
and  ten  in  the  summer,  at  night : 
at  cards  it  is  a  sequence,  or  three 
following  cards  of  one  sort:  in 
heraldry  it  is  the  division  of  a 
shield  into  three  equal  parts 

TieSf  in  navigation,  the  ropes  hy  which 
the  yards  hang;  in  mechanics, 
tension-rods 

Tiffna,  the  principal  timbers  of  a  roof 
extending  across  ancient  temples, 
in  contradistinction  to  the  trabes, 
which  were  timbers  placed  upon 
the  columns  or  walls  in  the  same 
direction  with  them.  The  tigna 
correspond  to  our  tie-beams. 

TVfef,  baked  clay  in  thin  plates  of 
different  shapes,  usedto  cover  roofs. 
Tiles  curiously  and  richly  orna- 
mented were  formerly  used  in  the 
early  Christian  churches  for  pave- 
ments. 

TiUeVf  a  piece  of  timber  fitted  into  the 
head  of  a  rudder,  to  which  it  forms 
a  handle 

Tilt-hammer,  The  most  simple  ma- 
chine by  which  iron  is  forged  is 
the  German  forge-hammer,  often 
called  the  tilt-hammer.  This  ma- 
chine, often  of  a  fwcifol  form,  is 
very  extensively  employed.  The 
leading  principle  sought  in  its  con- 
struction  is  solidity ;  and  various 
forms  have  been  invented  to  give 
permanency  to  the  structure,  which 
is  mainly  endangered  by  the  action 
and  re-action  of  the  strokes.  The 
cast-iron  tilt-hammer  varies  in 
weight,  according  to  the  purposes 
for  which  it  is  designed,  from  50 
to  400  pounds.  For  drawing  small 
iron  and  nail  rods,  a  hammer  of 
the  former  size  is  sufficiently  heavy ; 
but  for  forging  blooms  of  from  60 
to  100  pounds  in  weight,  a  ham- 
mer weighing  300  or  400  pounds 
is  employed.  Such  a  hammer 
should  be  cast  from  the  strongest 
gray  iron,  and  secured  by  wooden 
wedges  to  the  helve. 

464 


Timber^matif  in  nuning,  the  man  em- 
ployed in  placing  supports  of  tim- 
ber in  the  mine 

Tinmen,  in  ship-building,  the  nbs 
which  branch  outwards  from  tbe 
keel  in  a  vertical  direction 

Timbers  in  the  head,  in  ship-buildm|, 
pieces  with  one  end  bearing  on  the 
upper  cheeks,  and  the  other  ex- 
tended to  the  main  rail  of  tbe 
head 

Timbers  of  ermine,  a  term  in  armoury 
or  blazon;  the  rows  or  ranks  of 
ermine  in  noblemen's  capes 

Tin.  This  very  useful  metal  is  fouod 
in  small  round  lumps,  in  the  beds 
of  some  rivers  near  the  mines,  tbe 
principal  of  which  are  in  Cornwall 
but  it  is  generally  in  nature  as 
an  oxide,  though  occasionally  as  a 
sulphate,  and  associated  vnth  many 
other  metals.  Tin  is  a  silvery  white 
metal,  with  a  very  slight  shade  of 
yellow:  the  purest  is  the  grain-tiii. 
which  is  prepared  from  what  is 
found  in  the  river  beds,  and  knovn 
as  stream-tin,  and  is  judged  by  its 
splitting  when  a  mass  is  heated  till 
it  is  brittle  and  allowed  to  fall  from 
a  height.  It  is  very  malleable  asd 
soft:  it  dissolves  in  hydrochloric 
add,  evolving  hydrogen  gas :  nitric 
acid  converts  it  into  a  hydrated 
binoxide. 

Tin,  oxide  fjf.  When  tin  is  digested 
in  strong  nitric  acid,  a  whitish 
powder  is  deposited,  which,  after 
being  washed,  and  subsequently 
fused  and  pulverized,  is  known  in 
the  arts  imder  the  term  putty- 
powder,  and  is  used  for  polishing 
glass,  stones,  &c. 

71m  white  resembles  zinc  white  in 
many  respects,  but  dries  badly,  and 
has  even  less  body  and  colour  in 
oil,  though  superior  to  it  in  water. 
It  is  the  basis  of  the  best  white  in 
enamel  painting.  There  are  various 
other  metallic  whites  of  great  body 
and  beauty,  such  as  are  those  of 
bismuth,  antimony,  quicksilver,  and 
arsenic ;  but  none  of  them  are  of 
any  value  or  reputation  in  painting, 
on  account  of  their  great  dispo- 


TIR 


TOOLS. 


TOO 


sition  to  change  of  colonr,  both  by 
light  and  foul  air,  in  water  and  oil. 

Tincture,  a  staining  or  dyeing ;  also 
a  term  in  heraldry,  signifying  a 
variable  hae  of  arms 

Timely  a  kind  of  doth  composed  of 
silk  and  silver,  glistemng  Uke  stars 
or  sparks  of  fire 

Tire,  in  mechanics,  the  strong  iron 
hoop  that  binds  the  circumference 
of  a  wheel 

Tires,  of  locomotive  engines,  the  out- 
side hoops  round  the  wheels,  gene- 
rally with  a  flange  to  keep  and 
guide  them  on  the  rails.  Stephen- 
son's patent  engine  and  eight- 
wheeled  engines  are  usually  made 
without  flanges  on  the  tires  of  the 
driving  wheels.  Some  tires  are 
steeled  on  the  part  subjected  to 
most  wear,  which  renders  them 
more  durable. 

Titanate  of  iron  {Titaniferoiua  iron, 
Iron  sand,)  is  an  oxide  of  iron  and 
titanic  acid,  and  belongs  to  the  class 
of  the  magnetic  oxides.  It  is  at- 
tracted by  the  magnet,  is  of  a  deep 
black  colour,  metallic  lustre,  very 
hard,  and  perfectly  opaque ;  melts 
into  a  black  slag  by  a  high  tem- 
perature. It  is  generally  found 
near  volcanoes  or  volcanic  rocks, 
but  seldom  in  quantities  sufficient 
to  justify  the  erection  of  iron-works; 
nevertheless  the  quality  is  mostly 
good,  and  the  volcanic  regions 
around  the  lakes  of  America  may 
present,  in  the  course  of  time, 
encouraging  prospects. 

Tiianium.  This  metal  is  found  oc- 
casionally in  the  slag  of  smelting- 
fumaces,  in  small  cubical  crystids 
of  a  copper  colour:  it  exists  in 
anatase,  and  several  varieties  of 
titanate  of  iron,  but  combined 
with  oxygen. 

Ton,  a  weight  which  varies  in  dif- 
ferent  districts:  the  common  ton 
is  20  cwts.  of  112  lbs.,  or  2240  lbs.; 
in  Cornwall  the  miner's  ton  is  21 
cvTts.  of  1 12  lbs.,  or  2352  ibs. 

Tontine,  a  term  derived  from  the  name 
of  the  inventor,  Lorenzo  Tonti,  a  na- 
tive of  Naples,  who  originated  the 


scheme  so  called,  first  adopted  in 
1653,  in  France.  The  subscribers 
were  dirided  into  ten  classes,  ac- 
cording to  their  ages,  or  were  alt 
lowed  to  appoint  nominees,  who 
were  so  divided;  and  a  proportion- 
ate annuity  being  assigned  to  each 
class,  those  who  lived  the  longest 
had  the  benefit  of  their  survivor- 
ship, by  the  whole  annuity  being 
divided  amongst  the  diminished 
number.  Some  remarkable  cases 
have  occurred  in  England :  a  ton- 
tine of  a  recent  date  consisted  of 
a  less  number  than  ten  members, 
all  of  whom,  with  the  exception 
of  one,  died  within  a  very  few 
years  from  the  commencement, 
leaving  this  survivor  in  the  receipt 
of  an  enormous  sum  of  money 
annually,  derivable  from  the  pro- 
fits of  the  undertaking,  which  are 
unvarying 
Tools,  instruments  employed  in  the 
manual  arts  for  facilitating  mecha- 
nical operations,  namely,  hammers, 
punches,  chisels,  axes,  adzes,  planes, 
saws,  drills,  files,  &c.,  by  means  of 
percussion,  penetration,  separation, 
and  abrasion  of  the  substances  ope- 
rated upon ;  for  all  of  which  ope- 
rations various  motions  are  required 
to  be  given  either  to  the  tool  or  to 
the  work.  In  handicraft  work  the 
tool  receives  motion,  but  in  self- 
acting  or  automatic  tools,  motion 
may  be  given  to  either.  In  the 
case  of  the  turning  lathe,  the  tool 
remains  fixed,  and  the  object  moves. 
In  that  of  the  planing  machine,  the 
tool  may  remain  fixed,  or  be  made 
to  move  according  to  the  duty  re- 
quired to  be  performed.  In  almost 
idl  other  machines,  such  as  the 
slotting,  the  key -grooving,  the 
punching,  the  drilling,  the  nut- 
cutting,  the  teeth  of  wheels  cutting, 
the  boring,  the  screw-cutting  ma- 
chines, the  tools  receive  motion. 
In  the  screw,  bolt,  and  nut  machines . 
the  tool  is  either  moveable  or  fixed. 
The  use  of  handicraft  tools  is  coeval 
vrith  the  earliest  periods  of  anti- 
quity, and  the  racent  researches  of 


TOO 


TOOLS. 


TOO 


modem  tnvellen  have  proved  the 
andenta  to  ha^e  been  acquainted 
with  almost  all  the  tooli  now  in 
use.  The  potter's  wheel,  the  axe, 
the  chisel,  the  saw,  &c.,  attest  the 
perfection  to  which  the  mechanical 
arts  were  carried  by  the  Greeks 
and  Romans ;  and  subsequently  in 
the  arts  of  turning  exhibited  by  the 
Dondi  family,  in  the  construction  of 
their  clocks  and  of  machines  for 
spinning  silk,  in  the  middle  <rf  the 
13th  century,  in  Italy,  and  after- 
wai^  by  Bessoni,  De  la  Hire,  De 
la  Condamine,  Grand  Jean,  Plumier, 
and  Morin.  The  three  plates  of 
Bessoni  show  the  different  modes 
of  turning  and  cutting  screws  of 
all  sorts  of  fancy-work.  De  la  Hire 
shows  how  aU  sorts  at  polygons 
may  be  made  by  the  lathe,  and 
Condamine  shows  how  a  lathe  may 
be  made  to  turn  all  sorts  of  irre- 
gular figures  by  means  of  tracers 
moved  over  the  surfoce  of  models 
and  sculptures,  medals,  &c.;  and 
this  is  perhaps  the  first  idea  of  the 
machine  called  the  Tcmr  h  Por- 
trait. 

The  work  of  Plumier  enters  most 
extensively  into  the  art  of  turning, 
for  he  shows  the  construction  of 
the  lathe  and  its  different  parts, 
the  art  of  making,  hardening,  tem- 
pering, and  shan>ening  tools,  the 
different  kinds  of  motions  which 
may  be  given  to  the  lathe  by  means 
of  wheels,  eccentrics,  and  models, 
and  the  different  inventions  rdative 
to  works  of  art  which  have  been 
performed  by  the  lathe,  among 
which  may  be  mentioned  the  move- 
able or  slide  rest.  In  the  common 
rest  which  supports  the  tool,  the 
idea  of  fixing  the  tool  and  pudiing 
it  in  the  direction  of  the  parallel 
bed  of  the  lathe,  so  as  to  cause  the 
tool  to  traverse  the  work  pandlel 
to  it,  must  have  been  obvious;  and 
as  this  could  have  been  easily  ef- 
fected by  means  of  the  screw  and 
handle,  it  required  little  ingenuity 
to  carry  out  the  idea  to  its  fullest 
extent,  by  constructing  a  rest  to 

466 


allow  of  the  slide  traversing  the 
horizontal  or  vertical  plane  in  any 
direction.    The  machine  described 
by  Plumier  is  neither  more  nor 
less  than  the  alide-rest  and  pUmng 
machine  combined :  it  consists  of 
two  parallel  bars  of  wood  or  iron 
connected  together  at  both  extre- 
mities by  bolts  or  keya  of  suffioent 
width  to  admit  of  the  article  re- 
quired to  be  planed:  a  movesble 
frame  being  placed  between  the 
two  bars,  md  motion  being  giveii 
to  it  by  a  long  cylindrical  thiewL 
is  capable  of  giving  motioa  to  aay 
tool  which  may  be  put  into  the 
sliding  frame,   and   consequentlj 
either  causing  the  screw,  by  mens 
of  a  handle  at  each  end  of  it,  to 
push  or  draw  the  point  or  cuttinf 
edge  of  the  tool  either  way.   If 
also  motion  be  given  to  the  tool  by 
means  of  guides  upwards  or  down- 
wards, it  is  evident  that  any  loDd 
of  reticulated  form  can  be  given  to 
the  work,  as  in  the  machine  de- 
scribed by  Plumier,  which  wss  in- 
tended for  ornamenting^  the  handles 
of  knives,  and  which  ia  called  bj 
Plumier,  Machine  a   Mamche  de 
Couteau   d'Angkterre,     from  its 
having  been  an  Eng^ah  invention. 
The  Mackime  a  Gnuiefer,  described 
by  Bergeron,  a  mode  of  grooving 
columns,  is  probably  derived  from 
the  same  source,  tcom  its  resem- 
blanoe  to  the  Engliah  machise. 
The  origin  of  the  planing  machine, 
in  more  recent  times,  is   said  to 
have  arisen  from  the  grooving  or 
fluting  of  the  dravring  rollers  osed 
in  cotton  machines,  shortly  after 
the  introduction  of  Arkvnight's  in- 
ventions. The  patent  of  Sir  Samoel 
Bentham  in  1793,  for  various  new 
methods  for  working  wood,  metal, 
and  other  materials,  certainly  coo- 
templates   the  vrarking  of  tools 
simply  to  the  tools  employed 
in  the    planing   machine,   as  it 
comprehends  giving  all  sorts  of 
motion  to  tools :  and  the  patent  of 
Joseph  Bramah,  taken  out  in  1802, 
was  **  for  machinery  for  producing 


TOO 


TORSION. 


TOR 


straight,  paniUel,  and  smooth  sur- 
faces and  other  materials  requiring 
tmthf  in  a  manner  mcxre  expe- 
ditions and  perfect  than  can  be 
performed  by  the  nse  of  axes, 
screws,  planes,  and  other  cutting 
instroments  used  by  hand  in  the 
usual  way.** 

BiUingsby,  of  Bvkenshaw,  took 
oat  a  patent  in  1802,  for  boring 
cylinders  in  a  vertical  position,  al- 
though horizontal  machines  had 
their  adyantages.  The  boring  of 
large  cylinders  by  hmizontal  ma- 
ch&es  had  long  been  practised  by 
Smeaton,WiIkinson,Walker,Darby, 
and  Bonlton  and  Watt,  and  at  But- 
terley  and  other  great  iron-works ; 
but  it  was  many  years  subsequently 
that  the  yerti(»l  boring  machines 
came  into  use. 

As  respects  the  introduction  of 
the  first  planing  machines  which 
have  been  used  during  the  present 
century,  opinions  are  at  variance. 
Messrs.  Fox,  of  Derby,  the  eminent 
tool -makers,  state  that  the  first 
machine  employed  for  this  pur- 
pose was  constructed  by  Mr.  Fox, 
senior,  in  the  year  1821,  for  the 
purpose  of  plsning  the  wrought 
and  cast  iron  bars  used  in  the  lace 
machines :  the  machine  was  capable 
of  planing  an  article  1 0  feet  6  inches 
in  length,  22  inches  in  width,  and 
12  inches  in  depth:  others  give 
the  credit  of  the  invention  to  Man- 
chester, and  G.  Rennie,  Esq.,  puts 
in  a  claim  for  constructing  a  planing 
machine  with  a  moveable  bed, 
urged  by  an  endless  screw  and 
rack,  and  furnished  with  a  revolving 
tool,  so  early  as  1820,  having  several 
years  previously  employed  the  pflh- 
ciple  for  grooving  and  planing  pa- 
rallel bars. 

Mr.  Bramah,  in  1811,  employed 
the  revolving  cutter  to  plate  iron. 
Mr.  Clement  states  that  he  made  a 
planing  machine,  for  planing  the 
sides  of  weaving  looms  and  the 
triangular  bars  of  lathes,  previously 
to  1820.  He  afterwards  constructed 
a  beautiful  machine  for  planing 

467 


large  and  small  work  with  the 
greatest  accuracy.  The  bed  moved 
on  rollers,  and  the  tools  cut  both 
ways.  The  beautiful  work  exe- 
cuted by  this  tool,  for  Mr.  Babbage's 
calculating  machine,  evinces  the 
I^rfection  of  its  performance.  It 
is  thus  by  the  aid  of  automatic 
tools  that  the  greatest  precision  and 
identity  of  parts  in  machinery  is 
produced ;  and  it  is  probable  that, 
ere  long,  the  chisel,  the  file,  and  the 
grindstone  yriHl  be  banished  from 
the  factory,  and  that  nicety  of  parts 
and  uniformity  and  silence  of  action, 
blended  with  the  science  of  con- 
struction, will  eventually  supersede 
the  expensive  and  imperfect  con- 
struction of  the  handicraft  system. 

Toon  wood  is  of  a  reddish  brown 
colour,  rather  coarse-grained,  much 
used  aU  over  India  for  furniture 
and  cabinet-work 

Top  and  Butt  in  ship-building,  the 
general  method  of  working  the 
English  plank  (except  in  the  top- 
side) to  make  good  work  and  con- 
version, which  is  by  disposing  of 
the  top  end  of  every  plank  within 
6  feet  of  the  but-end  of  the  plank 
above  or  below  it,  leaving  aU  the 
planks  to  work  as  broad  as  possible, 
so  that  every  other  seam  is  fair 

Top-Hmber9f  in  ship-building,  the  up- 
permost timbers :  the  first  general 
tier  of  timbers  that  reaches  the  top 
of  the  side  are,  or  should  be,  called 
top-timbers ;  those  wMch  scarf  on 
the  heads  of  the  upper  futtock  are 
called  short  timbers 

Torriceliian  ttibe,  in  pneumatics,  a 
glass  tube  named  after  the  inventor, 
open  at  one  end  and  hermetically 
sealed  at  the  other 

TorrieelUan  vacuum.  This  is  pro- 
duced by  filling  a  tube  with  mer- 
cury, and  allowing  it  to  descend  to 
such  a  height  as  to  be  counter- 
balanced by  the  pressure  of  the 
atmosphere,  as  in  the  barometer. 

Torsion  is  that  force  with  which  a 
thread  or  wire  returns  to  a  state 
of  rest  after  it  has  been  twisted  by 
being  turned  round  on  its  axis 


TOR 


TRACERY. 


TRA 


Torsion 'electrometer,  an  apparatus 
for  measuring  the  intensity  of  elec- 
tricity 

Tonu,  the  convex  member  of  the 
Tuscan  and  Ionic  bases.  In  the 
attic  base  there  is  both  an  upper 
and  lower  torus.  • 

Tossing  f  ^zing,  or  Terloohing,  a  pro- 
cess consisting  in  suspending  ores 
by  violent .  agitation  in  water : 
their  subsidence  being  accelerated 
by  packing,  the  lighter  and  worth- 
less matter  remains  uppermost 

Tower,  an  ancient  elongated  vertical 
building,  variously  formed  and  con^ 
structed  in  different  countries 

TWn^a//, Mansion  House;  in  France, 
Hotel  de  Yille ;  in  Italy,  Palazzo 
Publico ;  in  Holland,  Stadhaus ;  an 
edifice  in  which  all  the  municipal 
laws  and  regulations  and  the  inte- 
rests of  a  city  are  conducted 

Tracery^  that  species  of  pattern- 
work  formed  or  traced  in  the  head 
of  a  Gothic  window  by  the  mul- 
lions  being  continued,  but  diverg- 
ing into  arches,  curves,  and  flowing 
lines  enriched  with  foUations. 

*'  Each  country  (says  Mr.Garbett 
in  his  '  Rudimentary  Treatise  on 
the  Principles  of  Design  in  Archi- 
tecture') has  had  its  successive 
styles  of  tracery,  and  each  has 
begun  with  the  simple  subdivision 
of  one  arch  into  two,  and  these 
sometimes  into  two  again,  filling 
up  the  space  between  the  heads 
with  a  circle,  as  at  Marburg;  a 
foiled  circle,  as  at  Salisbury  chap- 
ter-house, and  the  aisles  of  Co- 
logne ;  or  finally  a  foU^rcle,  as 
at  Westminster,  and  the  clerestory 
of  Cologne,  where  it  is  subfoiled : 
thence  proceeding  to  pack  together 
such  forms  oyer  an  odd  number  of 
lights,  to  which  the  method  of 
continual  bisection  would  not  apply, 
as  at  the  aisles  of  York ;  and  thus 
the  first  kind,  which  may  be  called 
packed  tracery,  became  complete. 
Deviations  from  the  principle  of 
packing  led  to  the  general  tracery, 
absurdly  called  ^  geometrical  s*  for 
all  Gothic  tracery  is  gpeometrical, 

468 


none  is  hand-drawn.  This  beau- 
tiful purely  unmeaning  tracery  was 
succeeded  in  all  countries  bv  the 
flowing  loop  or  leaf,  and  then  by 
the  peculiar  national  After-Gothic. 
Germany,  however,  as  it  had  been 
the  first  to  perfect,  was  also  the 
last  to  abandon  the  ^geometrical' 
tracery, which  continued  there,even 
into  the  fifteenth. century,  our  Per- 
pendicular Period.  .England  and 
jp'rance,  however,  in  the  fourteenth 
century,  abandoned  the  unmeaning 
for  the  flowing;  leaf -tracery;  and 
this,  notwithstanding  its  beauty, 
had  hardly  time  to  show  itself 
before  it  was  superseded,  here  by 
the  perpendicular,  and  in  France 
by  the  flamboyant.  Hence  it  hap- 
pens that  of  the  three  great  classes 
of  tracery, — geometrical,  flovnng, 
and  perpendicular, — ^while  the  last 
is,  as  every  one  knows,  by  far  the 
conmionest  in  England,  the  most 
abundant  kind  in  France  is  flowing 
(flamboyant),  and  in  Germany  geo- 
metrical, i.  e.  unmeaning. 

"  The  unmeaning  tracery  of  Ger- 
many is  very  beautiful,  and  gene- 
rally partakes  of  the  packed  cha- 
racter; the  following  forms,  which 
are  the  elements  of  German  tra- 
cery, occurring  very  abundantly. 


Elements  of  Germaa  tracery. 


"  The  conTei-sidcd  triingle  tad 
square  itre  placed  in  all  posi. 
tiOHB  indiffeTGiitly,  and  the  frame- 
len  trefoila  and  qnatrefaila  are 
frequently  formed  on  the  baiia  of 
theae  fignrei  uutead  of  the  cir- 
cle. The  failings  and  subfoilinga, 
formed  by  a  very  narrow  bat  deep 
ebkmfered  member,  leave  their 
little  spandrila  (called  ei/ti  by  our 
vorkmeD)  entirely  open,  thui  pro- 
dndng  almoat  ibe  lightneaa  of 
metal-work. 

"  The  Go-mana  leized  on  the 
idea  olgrwlh,  and  the  budding  and 
(planting  expression ;  but  perhaps 
^e  French  were  most  >acceitfal  in 
increasing  the  aspiring  eipreaaion  i 
by  a  alight  change  in  the  prerul- 
iag  forma  of  the  flowii^  tracery, 
they  converted  the  loops  or  leaves 
into  Same-like  forms,  till  the 
flamboyant  buildings  appeared  not 
vegetatiiiK,  as  in  Germany,  hut 
ibuing  from  the  foundation  to  the 
bristling  Enials.  The  difference  be. 
tween  this  style  of  tracery  and  our 
own  flowing  style  (eiempliSed  in 
the  weat  window  at  York),  is,  that 


while  the  npper  ends  of  our  loops 
or  leaves  are  round  or  dmply 
pointed,  i.  t.  yntb  finite  anglei,  the 
upper  ends  in  France  terminate, 
like  tbe  lower,  in  imgki  qfeoniaet 
(thoae  formed  by  two  carves  tliat 
have  a  common  tangent).  It  was 
uecessajy  to  the  leafy  effect  that 
the  bicer  angles  should  be  tan- 
gential) but  to  the  flame.like  ef- 


finite;  and  hence  some  examples 
of  flamboyant  tracery,  turned  up- 
side  down,  form  a  kind  of  Icaf- 

"  Our  countrymen,  howi 
adopted  a  method  which  was  less 
conducive  to  tbe  aspiring  expres- 
sion, andwMch  conducted  them  to 
•  style  less  rich  and  certainly  lets 


varied  than  any  of  the  other  After- 
Gothics.  Erroneonsly  supposing 
that  an  abundance  of  verticd  line* 
would  incteue  this  character,  they 
were  led  to  convert  all  the  flowing 
Unes  of  the  window  tracery  into 
vertical  ones,  to  omit  the  capitals 
of  nearly  an  the  smaller  shafts  or 
shaftlets,  thus  converting  what  had 
been  blank  arcades  into  aii 
panels,  and  then  to  multiply,  i 
minish,  and  extend  these  panels 
and  endless  repetition  of  vertical 
lines  over  every  part  of  the  inte- 
lioi,  tmd,  in  florid  buildings,  i 
of  the  exterior." 


TRA 


TRACTION. 


TRA 


TVaction,  in  mechanics,  is  the  adf  of 
drawing  a  body  along  a  plane, 
usually  by  the  power  of  men,  ani- 
mals, or  steam ;  as  when  a  vessel 
is  towed  on  the  surface  of  water,  or 
a  carriage  moved  upon  a  road. 
The  power  exerted  in  order  to  pro- 
duce this  effect  is  called  the  force 
of  traction. 

Numerous  experiments  have  been 
made  for  the  purpose  of  ascertain- 
ing the  value  of  a  force  so  exerted ; 
and  when  men  are  employed  to 
draw  laden  boats  on  canals,  it  is 
found  that  if  the  work  be  continued 
for  several  days   successively,  of 
eight  hours  each,  the  force  of  trac- 
tion is  equivalent  to  a  weight  of 
31^  lbs.  moved  at  the  rate  of  2  feet 
per  second,  or  1^  mile  per  hour,  (it 
being  understood  that  such  weight 
is  imagined  to  be  raised  vertically 
by  means  of  a  rope  passing  over  a 
pulley,  and  drawn  in  a  horizontal 
direction.)     The  force  of  traction 
exerted  when,  without  moving  from 
his  place,  a  man  pulls  horizontally 
against  a  weight  so  suspended,  is 
estimated  at  70  tbs.    The  action  of 
a  horse  in  drawing  a  vessel  on  a 
canal  is  said  to  be  equivalent  to  a 
weight  of  180  ibs.  raised  vertically, 
as  above  supposed,  with  a  velocity 
of  3^  feet  per  second,  or  2^  miles 
per  hour;  but  this  estimate  has 
been  considered  too  high;  and  from 
experiments  which  have  been  made 
on  the  power  of  horses  in  waggons, 
carts,  and  coaches,  on  level  ground, 
it  is  found  that  the  force  of  traction 
exerted  by  a  stout  horse  is  equiva- 
lent to  80  tbs.  raised  at  the  rate  of 
4§  feet  per  second,  or  3  miles  per 
hour.      Tredgold    considers    that 
a  horse  exerts  a  force  of  traction 
expressed  by  125  tbs.  raised  at  the 
rate  of  3f  feet  per  second,  or  2^ 
miles  per  hour.    A  man  or  a  horse 
can,  however,  double  his  power  of 
traction  for  a  few  minutes  without 
being  injured  by  the  exertion ;  and 
when  the  carriage  is  in  motion,  so 
that  the  friction  on  the  ground  is 

alone  to  be  overcome,  a  horse  can 

—  I 

470 


draw,  during  a  short  time,  on  a 
level  road,  a  wei^t  exceeding 
1500  lbs. 

The  force  of  traction  is  found  to 
vary  nearly  with  the  term  («p— r)-, 
where  w  is  the  greatest  walking 
velocity  of  a  man  or  horse  when 
unresisted  (6  feet  per  second,  or  4 
miles  per  hour,  for  a  man,  and 
10  feet  per  second,  or  6^  miles  per 
hour,  for  a  horse),  and  9  is  the 
velocity  with  which  the  vessel  or 
carriage  is  moved.  From  theoreti- 
cal considerations  it  has  been  de- 
termined that  the  g^reatest  effect  is 
produced  when  the  velocity  of  the 
object  moved  is  one-third  of  that 
with  which  the  man  or  j^niTimi  can 
walk  when  unresisted. 

If  a  wheel-carriage  were  situated 
on  a  level  plane  which  opposed  no 
resistance,  it  is  evident  that,  what- 
ever were  the  diameter  of  the 
wheels,  the  smallest  conceivable 
power  of  traction  applied  to  the 
axle  would  suffice  to  put  the  car- 
riage in  motion.  But  when  a  wheel 
in  moving  meets  vnth  an  obstacle 
on  the  ground,  that  obstacle  is 
pressed  at  the  point  of  contact  by 
a  force  acting  in  the  direction  of  a 
line  drawn  to  it  from  the  centre  of 
the  wheel,  and  arising  from  that 
part  of  the  weight  which  is  sup- 
ported by  the  wheel,  together  with 
the  force  of  traction ;  therefore,  by 
the  *  resolution  of  forces,'  the  ratio 
between  the  resistance  which  is  to 
be  overcome  by  the  moving  power 
and  the  weight  on  the  wheel  vnll 
become  less  as  the  diameter  of  the 
wheel  is  increased  :  also  the  most 
advantageous  direction  in  which 
the  force  of  traction  can  be  exerted 
is  perpendicular  to  the  line  of  press- 
ure drawn  from  the  centre  of  the 
wheel  to  the  obstacle.  But  the 
height  of  the  wheels  cannot  exceed 
certain  limits,  depending  on  the  use 
to  which  the  carriage  is  applied; 
and  when  the  latter  has  four  wheels, 
the  height  of  those  which  are  b 
front  must  be  snch  only  as  will 
allow  it  to  be  turned  round  within 


TRA 


TRANSEPT. 


TRA 


a  given  space :  also,  when  a  horse 
is  employed  to  move  a  carriage, 
attention  must  be  paid  to  the  con- 
ditions under  which  his  power  may 
be  adyantageonsly  exerted. 

It  was  first  observed  by  M.  De- 
parcienx,  and  published  in  the 
*  Memoires  de  TAcad^mie  des  Sci- 
ences/ 1 760,  that  horses  draw  heavy 
loads  rather  by  their  weight  than 
by  their  muscular  force.  Sir 
David  Brewster  has  also  remarked, 
that  when  the  resistance  is  great, 
a  horse  lifts  both  its  fore-feet  from 
the  ground ;  then,  using  his  hinder- 
feet  as  a  fulcrum,  he  allows  his 
body  to  descend  by  its  weight,  and 
thus  oTcrcomes  the  obstacle :  and 
it  may  be  added,  that  when  this 
action  takes  place  with  a  two- 
wheeled  carriage,  if  the  loading  is 
disposed  so  that  some  portion  of  it 
may  press  on  the  horse's  back,  the 
effect  of  the  animal's  weight  will 
thereby  be  increased.  Now,  if  the 
traces,  or  the  shafts  of  the  carriage, 
were  attached  to  the  horse's  collar, 
near  his  centre  of  gravity,  a  line 
imagined  to  be  drawn  from  the 
latter  point  to  his  hinder-feet  may 
represent  his  weight,  and  a  line 
drawn  perpendicularly  from  his 
feet  upon  a  plane  passing  through 
the  traces  or  shafts  may  represent 
the  lever  ef  resistance :  but  while 
the  former  line  remains  the  same, 
this  lever  becomes  less  as  the  plane 
of  traction  (that  of  the  traces  or 
shafts)  inclines  more  upwards  from 
the  wheel ;  and  therefore,  in  order 
that  the  power  of  the  horse  may  be 
advantageously  applied,  the  dia- 
meter of  the  wheel  should  be  as 
small  as  is  consistent  with  other 
circumstances. 

Experiments  have  shown  that 
when  the  angle  of  traction,  as  it  is 
called,  that  is,  the  angle  which  the 
plane  of  the  traces  makes  with  the 
road  on  which  the  carriage  is  mov- 
ing, is  15  or  16  degrees,  a  horse 
palls  with  good  effect;  and  the 
height  of  the  points  at  which  the 
traces  are  attached  to  a  horse's 

"471 


collar  being  about  4  feet  6  inches 
from  the  ground,  it  follows  that,  in 
order  to  obtain  this  inclination,  the 
lower  extremities  of  the  traces  or 
shafts  should  be  2  feet  3  inches 
from  the  ground.  In  general,  how- 
ever, in  two-wheeled  carriages  the 
height  of  these  extremities  is  about 
3  feet. 

As  an  example  of  the  force  of 
traction  exerted  by  steam,  it  may 
be  stated,  that  on  a  level  line  of 
railway,  an  engine  with  an  11-inch 
cylinder,  and  having  an  effective 
pressure  of  50  lbs.  per  square  inch 
in  the  boiler,  drew  50  tons  at  the 
rate  of  30  miles  per  hour,  working 
10  hours  daily ;  and  that  the  same 
engine,  with  an  equal  pressure  in 
the  boiler,  drew  160  tons  at  the 
rate  of  15^  miles  per  hour. 

TVailf  a  running  enrichment  of  leaves, 
flowers,  tendrils,  &c.,  in  the  hollow 
mouldings  of  Gothic  architecture 

Trail' boardSf  in  ship-building,  the 
carved  work  between  the  cheeks ; 
that  which  is  fastened  to  the  knee 
of  the  head 

Drailing  springs,  the  springs  fixed  on 
the  axle-boxes  of  the  trailing  wheels 
of  a  locomotive  engine,  which  bear 
slightly  against  the  side  frames,  so 
as  to  leave  as  much  weight  as  pos- 
sible upon  the  driving  springs,  and 
to  assist  in  deadening  any  shock 
which  may  take  place 

Trailing  wheels,  the  wheels  placed 
behind  the  driving  wheels  of  a 
locomotive  engine 

lyammel,  a  rod  of  iron  or  wood, 
vrith  sliding  pieces  having  points, 
which  can  be  fixed  at  any  distance 
apart ;  used  for  drawing  large  cir- 
cles, or  setting  off  distances 

Transept,  the  transverse  portion  of  a 
cruciform  church;  that  part  which 
is  placed  between  and  extends  be- 
yond those  divisions  of  the  building 
containing  the  nave  and  the  choir 

Transit,  a  term  expressing  the  pas- 
sage of  a  railway  train,  &c.  In 
astronomy,  the  passage  of  any  hea- 
venly body  over  a  larger  one,  as 
Mercury  or  Venus  over  the  sun. 


TRA 


TRENCH. 


TR£ 


88  applied  to  the  8rchitec- 
tore  of  the  middle  8nd  l8ter  8ge8, 
the  progress  of  chsnging  firom  one 
style  to  another.  There  were  several 
periods  of  transition :  Romanesque 
to  Saxon,  Norman  to  Early  English, 
Early  English  to  Decorated,  from 
the  Decorated  to  the  Perpendicular 
to  that  of  the  Tador  and  to  that  of 
the  Elizabethan  age. 

TVtnuom,  a  horizontal  mnUion  or 
cross-bar  in  a  window.  The  most 
ancient  examples  are  found  in  the 
Early  English  style. 

TVoMom,  in  carpentry,  a  thwart-beam 
or  lintel  over  a  door.  In  ship- 
building, certain  timbers  extending 
across  the  stern-post  of  a  ship, 
to  fortify  and  strengthen  it.  In 
mathematics,  the  yane  of  an  in- 
strument called  a  cross-staff,  being 
a  piece  of  wood  fixed  across,  with 
a  square  socket  upon  which  this 
slides. 

Trofupareney,  that  quality  of  certain 
bodies  by  which  they  transmit  the 
rays  of  hght,  in  contradistinction 
to  opacity 

Trafupontim,  in  music,  the  changing 
a  tune  or  lesson,  and  putting  it  into 
a  higher  or  lower  key  or  def 

TVautrOf  horizontal  timbers  in  the 
roof  of  a  building.  The  term  is 
applied  to  the  transverse  beams  of 
a  gallery  which  extend  from  side 
to  side  and  connect  the  ribs,  in  the 
same  manner  as  these  horizontal 
pieces  connect  the  axis  or  princi- 
pals of  a  roof. 

Trannerse,  in  geometry,  something 
that  goes  across  another,  frt>m  cor- 
ner to  comer,  like  the  diagonals  of 
a  square  or  parallelogram 

Tratuyte,  a  narrow  or  triforial  pas- 
sage 

7Wi/i«2«tfm,  in  geometry,  a  plane 
figure  contain^  under  four  right 
lines,  of  which  neither  of  the  oppo- 
site sides  are  parallel' 

T\rqpe2oidi  an  irregular  figure  whose 
four  sides  are  not  parallel,  resem- 
bling a  trapezium 

TVaoeUer,  in  navigation,  a  sort  of 
thimble,  whose  diameter  is  much 

472 


larger,  in  proportion  to  the  breadth 
of  its  sur&oe,  than  the  common 
ones:  it  is  intended  to  facilitate 
the  hoisting  and  lowering  the  top- 
gaUant  yards  at  sea 

DraveOmg  crane,  a  crab  fixed  on  a 
carriage  which  may  be  moved  upon 
rails  across  a  building,  and  the 
cross-rails,  together  with  the  car- 
riage, moved  lengthwiae  upon  otiier 
rails  fixed  at  or  near  the  top  of  the 
building 

TVoMrse  aaUmff,  in  navigatimi,  is  the 
variation  or  alteration  of  a  ship's 
course  occasioned  by  varioBB  causes; 
or  it  is  a  compound  coorae  in  which 
several  different  conraes  and  dis- 
tances are  known 

Trmene^tablef  in  navigation,  ia  the 
same  as  a  table  of  diffisrence  and 
departure,  ready  calculated  for  any 
distance  under  100  milea 

TVeadle,  a  lever  or  frame  <9onnected 
by  a  rod  to  the  crank  of  a  foot- 
lathe,  to  give  motion  to  the  crank- 
shaft: it  is  pressed  down  by  the 
left  foot  of  the  turner,  and  raiaed 
by  the  centriliig&l  force  of  the  fly- 
wheel or  lasge  pulley  which  is 
fixed  on  the  shaft 

Treamryf  a  building  or  an  apartment 
where  money  or  valuablea  axe  de- 
posited 

7VM-iun2»,  or  Trermeb^  in  ahip- 
building,  long  cylindrical  wooden 
pins 

Jh^finl,  an  ornament  formed  by 
mouldings  so  arranged  aa  to  re- 
semble the  trefoil  or  three-leaved 
clover 

Treilia,  a  gate  or  screen  of  open  work ; 
lattice -woriL  either  of  metal  or 
wood 

Trench,  a  ditch;  a  defence  for  soldiers. 
Trenches,  approaches,  or  attacks, 
are  works  carried  on  by  besiegers, 
with  parapets  for  the  men  to  gain 
ground  and  draw  near  a  citadel  or 
fortification :  if  the  ground  be  hard 
or  rocky,  trenches  are  raiaed  above 
it  with  fisscines,  bags  of  earth»  &c ; 
but  if  the  earth  can  be  easily  dug, 
then  a  ditch  or  way  ia  sunk,  and 
edged  with  a  psrapet  next  to  the  { 


TRE 


TRIGLYPHS. 


TRI 


besieged,  the  depth  being  com- 
monly about  six  or  seven  feet, 
and  the  breadth  seven  or  eight 
feet. 

Trend,  in  navigation,  to  bend,  to  lie 
in  a  particular  direction 

TVestle'tree§y  in  ship-building,  two 
strong  bars  of  timber  fixed  hori- 
zontaUy  on  the  opposite  sides  of 
the  lower  mast-head,  to  support 
the  tnme  of  the  top  and  the  weight 
of  the  topmast 

Tret,  an  allowance  in  weight  for 
waste  or  impurities 

Triangle,  a  figure  bounded  by  three 
sides,  and  consequently  containing 
three  angles.  Triangles  are  of  the 
several  lands,  plane' or  rectilinear^ 
spherical,  and  curvilinear. 

JVibometer,  in  mechanics,  a  term 
applied  to  an  instrument  for  esti- 
mating the  friction  of  metals 

IVibunes,  magistrates  among  the  old 
Romans,  chosen  to  preserve  the 
privileges  and  secure  the  liberties 
of  the  people  against  the  power  and 
encroachments  of  the  nobles:  at 
first  their  number  was  but  two,  and 
these  afterwards  associated  three 
more  to  them,  whose  number  was 
in  process  of  time  increased  to  ten. 
Their  authority  was  so  great  that 
they  could  assemble  the  people  for 
what  purposes  they  pleased,  hinder 
the  deliberations  of  the  senate,  ap- 
prove or  annul  its  decrees,  summon 
the  other  magistrates  before  the 
people,  and  also  their  own  col- 
leagues and  associates :  they  went 
so  far  as  sometimes  to  imprison 
consuls  and  fine  dictators.  At  first 
their  jurisdiction  reached  but  a 
mile  out  of*the  city  of  Rome,  but 
some  time  afterwards  it  was  ex- 
tended into  the  provinces.  These 
officers  kept  their  doors  open  day 
and  night,  to  receive  such  of  the 
common  people  as  sought  for  shel- 
ter with  them.  The  office  grew 
into  so  much  authority  and  honour, 
that  the  greatest  men  in  the  state 
chose  it,  and  by  clashing  with  the 
consuls  and  senate  occasioned  great 
tumults.    There  were  also  miUtary 

473 


tribunes,  but  their  powers  were 
more  limited. 

Tribute,  in  mining,  a  proportion  of 
the  ore  which  the  workman  has 
for  his  labour.  Tributers  gene- 
rally work  in  gangs,  and  have  a 
limited  portion  of  a  lode  set  them, 
called  a  'tribute  pitch,'  beyond 
which  they  are  not  permitted  to 
work,  and  for  which  they  receive  a 
certain  portion  of  the  ore,  or  so 
much  in  the  pound  as  agreed  upon 
in  value  of  what  they  raise. 

TrieihUium,  the  eating-room  of  a  Ro- 
man house;  so  ctSled  because  in 
general  it  contained  couches  upon 
which  the  ancients  or  their  guests 
reclined  at  their  meals.  The  term 
was  also  applied  to  the  conches 
themselves. 

Triforhan,  the  gallery  or  open  space 
between  the  vaulting  and  the  roof 
of  the  aisles  of  a  church,  generally 
lighted  by  windows  in  the  external 
wall  of  the  building  and  opening  to 
the  nave,  choir,  or  transept  over 
the  main  arehes.  In  the  Temple 
church  it  is  built  around  the  nave, 
and  has  a  curious  and  singular 
effect. 

Triglyphs,  in  architecture,  ornaments 
repeated  at  equal  intervals  in  the 
Doric  frieze.  Each  triglyph  con- 
sists of  two  entire  gutters  or  chan- 
nels cut  to  a  right  angle,  called 
glyphs,  and  separated  by  their  in- 
terstices, called/tfffiKma,  from  each 
other  as  well  as  frt>m  two  other 
half- channels  that  are  fbrmed  at 
the  sides. 

Trigonometry',  the  art  of  measuring 
triangles,  or  of  calculating  the  sides 
of  any  triangle  sought,  either  plain 
or  spherical  (See  Ordnance  Sur- 
vey.) 

7Vtm,in  navigation,  the  best  posture 
of  a  ship's  proportion  of  ballast, 
arrangement  of  sails,  and  position 
of  masts,  with  a  view  to  her  sailing 
well 

Trimmer,  a  piece  of  timber  inserted 
in  a  roof,  floor,  wooden  partition, 
&c.,  to  support  the  ends  of  any  of 
the  joists,  rafters,  &c. 


TRI 


TUBES. 


t\:b 


Tringle,  in  architecture,  a  name  com- 
mon to  several  little  square  mem- 
bers or  ornaments,  as  regulets, 
lestets,  and  platbands 

Tripodf  any  utensil  or  article  of  fur- 
niture supported  upon  three  feet 

Tr^tiCf  a  tablet  in  three  divisions, 
to  open  and  shut,  the  two  outer 
folding  over  the  centre  one  vrhen 
closed 

Trisectumt  the  division  of  a  line,  an 
angle,  &c.  into  three  equal  parts 

TVocAt/ttf,  a  hollow  moulding ;  also 
called  seotia;  constantly  occurring 
in  the  bases  of  the  classical  orders 
of  architecture 

Trochoid,  in  geometry,  a  particular 
description  of  curve  generated  by 
the  motion  of  a  wheel 

Tropics,  two  lesser  circles  on  the 
globe  or  sphere ;  one  on  each  side, 
distant  23^°  from  the  equator, 
which  are  the  bounds  or  limits  of 
the  sun's  deviation  from  the  equa- 
tor :  at  his  approach  to  these  cir- 
cles the  sun  seems  to  stand  still 
for  a  few  days,  and  then  returns 
towards  the  equator  again :  that 
on  the  north  side  is  called  the 
tropic  of  Cancer,  and,  when  the 
sun  is  there,  makes  our  longest 
day;  and  that  on  the  south  side 
is  called  the  tropic  of  Capricorn, 
and  causes  the  longest  night. 

Troubles,  in  mining,  faults  or  inter- 
ruptions in  the  stratum 

Trticks,  in  navigation,  circular  flat 
pieces  of  elm,  with  a  small  sheave 
on  each  side,  fixed  upon  the  upper 
end  of  flj^-staffs,  and  used  to  reeve 
the  halliards 

Truncated,  in  geometry,  a  pyramid 
or  cone,  the  top  or  vertex  of  which 
is  cut  off  by  a  plane  parallel  to  its 
base 

Trunk  engine,  a  marine  steam  engine 
used  for  diving  a  propeller:  the 
cylinder  is  fixed  horizontally 

TVunkinff,  the  process  of  extracting 
ores  firom  the  slimes :  the  ores  sub- 
sequently undergo  the  process  of 
racking  and  tossing 

Trunnions,  knobs  of  metal  in  pieces 
of  ordnance  which  project  from 

474 


the  sides  and  bear  the  guns  on  the 
cheeks  of  the  carriage 

IVuss,  the  collection  of  timbers  form- 
ing one  of  the  principal  supports  to 
a  roof,  framed  together  to  give  mu- 
tual support  and  to  prevent  strain- 
ing or  distortion  from  the  super- 
incumbent weight 

Truss,  to  strain,  support  or  keep  tight: 
a  trussed  roof  is  one  which  by  means 
of  the  tie-beams,  rafters,  king-posts, 
&c.,  is  strained,  or  held  together  in 
its  proper  position 

TVussing,  in  carpentry  and  ship-build- 1 
ing,  a  series  of  diagonal  braces  dis- 
posed in  triangles,  the   sides  of 
which  give  to  each  other  a  mutual 
support  and  counteraction 

Trussing-beds,  in  Tudor  times,  were 
beds  which  packed  into  chests  for 
travelling :  in  cases  of  frequent  re- 
moval, they  must  have  been  found 
very  convenient.  John  of  Ghent 
seems  to  have  always  slept  in  such 
beds. 

Tub,  a  cast-iron  cylinder  put  in  the , 
shaft  instead  of  bricking,  for  the 
purpose  of  beating  out  the  water 
and  making  it  rise  to  a  level 

Tubes,  in  locomotive  engines,  are  of 
brass  or  iron,  about  two   inches 
outside  diameter.    They  are  of  the 
same  length  as  the  boiler,  and  fixed 
in  it  by  a  ferrule  driven  in  at  each 
end,  which   makes  them   steam- 
tight.    They  are  surrounded  with 
water   externally,  and    internally 
open  to  the  atmosphere  by  the 
chimney.    The  heated  gases  and , 
smoke  from  the  fire  pass  through  \ 
them,  and  they  are  thus  the  means  I 
of  rapidly  generating  steam.    The 
number  of  tubes  in  boilers  varies  • 
from  60  to  70  up  to  above  200, 
according  to  the  power   of  the  > 
engine. 

Tube  ferrules,  in  locomotive  engines, 
slightly  tapered  hoops,  one  of  which 
is  driven  in  at  each  end  of  each 
tube,  to  fix  it  securely  in  the  boiler: 
formerly  they  were  made  of  steel 
and  iron;  now,  cast-iron  ferrules 
are  found  to  answer  very  well 

Tube  plugs,  in  locomotive  engines. 


TUB 


TUBULAR  BOILERS. 


TUB 


are  formed  of  tapered  iron  or  wood, 
and  used  for  driving  into  the  end  of 
a  tube  when  burst  by  the  steam 

Tubeplv^-ram,  in  locomotive  engines, 
a  long  rod  with  a  socket  end,  into 
which  the  plug  fits,  and  is  thus 
driven  into  the  burst  tube,  and  the 
plug-ram  vnthdrawn 

Tubular  Boilers.  Boilers  of  an  an- 
gular, prismatic,  or  indeed  any  but 
a  cylindrical  form, — or  even  then 
if  not  made  of  wrought  metal, — be- 
come the  peculiar  seat  of  danger 
in  high-pressure  engines;  and  all 
sorts  of  safety  apparatus,  as  well 
for  preventing  too  great  a  pressure 
as  for  avoiding  other  sources  of 
danger,  are  but  uncertain  in  their 
operation,  and  not  to  be  depended 
upon.  The  great  object  to  be  sought 
is  so  to  construct  boilers  that  their 
explosion  may  not  be  dangerous  in 
its  result. 

This  condition  has  been  approxi- 
mated to  by  the  invention  and  ap- 
plication of  tubular  boilers ;  but  it 
would  seem  that  these  have  been 
suggested  rather  by  the  necessity 
of  providing,  for  many  technical 
purposes,  and  particularly  for  steam 
carriages,  boilers  of  less  content 
and  weight,  than  by  the  desire 
of  removing  or  lessening  danger 
from  explosion.  Tubes  should  have 
that  form  which  is  best  adapted 
to  resist  pressure,  viz.  the  cy- 
lindrical. If  they  are  of  small  dia- 
meter, of  not  too  great  thickness, 
and  of  suitable  material,  they  may 
be  made  to  carry  out  the  before- 
named  principle ;  t.  e.  they  them- 
selves, in  case  of  bursting,  will  not 
cause  any  dangerous  consequences 
to  the  neighbouring  persons  or  pro- 
perty. This  has  been  amply  proved 
by  experience. 

Uirfortunately,  however,  there 
are  no  tubular  boilers  which  satisfy 
all  conditions  required.  The  sub- 
ject is  often  mentioned  as  one 
of  little  difficulty,  easy  of  decision, 
and  unencumbered  with  practical 
obstacles ;  but  such  is  the  language 
only  of  the  prejudiced  and  the  in- 


experienced. To  arrive  at  the  truth, 
it  must  be  sought  with  long-con- 
tinued perseverance,  and  with  no 
small  share  of  physical  knowledge, 
as  the  subject  is  beset  vnth  diffi- 
culties on  every  side. 

It  becomes  a  most  complex  pro- 
blem to  construct  a  tubular  boiler 
for  a  large  supply  of  steam,  by  rea- 
son of  the  difficulty  of  arranging 
and  connecting  the  great  number 
of  tubes  it  must  contain  into  one 
convenient  whole.  The  modern 
English  locomotive  boilers  cannot 
be  legitimately  called  tnbular  boil- 
ers, because  they  fail  altogether  in 
the  grand  distinguishing  quality  of 
all  such, — namely,  the  small  dia- 
meter of  the  generating  apparatus: 
the  tubes  of  these  boUers  are  no- 
thing more  than  a  splitting-up  or 
subdivision  of  the  fire-tube  of  the 
Trevithick  steam-carriage  boiler. 
From  their  great  outer  diameter, 
locomotive  boilers  do  not  avoid 
the  evil  of  the  old  capacious  form, 
and  therefore  do  not  diminish  the 
objection  to  it:  they  have  also  a 
defect  in  the  close  proximity  of  the 
tubes  to  each  other,  whereby  the 
water  space  between  them  is  ren- 
dered too  confined,  and  the  heated 
tubes  become  liable  to  be  laid  bare 
of  water.  This  circumstance  gives 
the  key  to  the  well-known  fact, 
that  the  tubes  become  so  soon  de- 
stroyed, or,  at  least,  require  con- 
stant repair,  and  add  to  the  mischief 
occasioned  by  their  expansion, 
through  their  connection  vdth  the 
end  pktes  of  the  cylindrical  part  of 
the  boiler.  It  is  evident  that  from 
the  passage  upwards  of  the  steam 
formed  among  the  lower  tubes,  the 
upper  ones  must  be  most  liable  to 
be  uncovered  with  water;  while 
these,  being  exposed  to  the  hottest 
part  of  the  fire  current,  are  most 
likely  to  receive  damage  there- 
from. 

A  tubular  boiler  ought  to  pre- 
serve, as  much  as  possible,  the  tu- 
bular form  in  all  its  parts ;  or,  at 
least,  the  larger  portions  ought  to 


475 


TUB 


TUBULAR  BOILERS. 


TUB 


be  cylindrical,  and  not  of  too  great 
diameter,  or  should  be  so  strongly 
made  that  the  tubes  should  form 
the  weakest  part  of  the  whole 
boiler.  The  tubes  themselves  should 
be  of  such  diameter,  and  be  con- 
structed of  such  metal,  that  in  case 
of  their  actual  biursting,  no  dan- 
gerous explosion  may  ensue.  This, 
however,  is  only  possible  when 
their  thickness  is  so  small,  and 
the  metal  of  such  a  kind,  that 
bursting  takes  place  by  a  compara* 
tively  small  internal  pressure,  and 
is  followed  by  only  a  ripping  open 
of  the  tube,  and  not  a  scattering 
about  of  massive  fragments.  Under 
all  circumstances,  however,  the 
tubes  must  be  the  sole  generating 
vessels:  they  alone  must  receive 
the  action  of  the  fire,  and  be  ex- 
posed to  its  destructive  influence. 
All  other  and  larger  vessels,  or 
parts  connected  with  the  tubes, 
should  be  most  carefully  protected 
from  not  only  this  but  all  other 
dangerous  influences,  in  order  that 
they  may  remain  in  their  original 
proved  condition  of  strength. 

Only  such  a  tubular  boiler  as 
fulfils  all  these  conditions  can  be 
called  a  safe  one.  In  its  use  there 
is  no  further  danger  from  high- 
pressure  steam,  and  near  it  its 
owner  may  repose  undisturbed  by 
a  care  for  the  safety  of  life  or  pro- 
perty. 

The  requisites  in  the  use  of  the 
tubes  are  the  following: — They 
must  be  placed  in  such  a  position, 
with  regard  to  the  furnace,  that  the 
flame  may  act  upon  them  in  the 
most  favourable  manner,  and  that 
the  heat  may  be  absorbed  as  com- 
pletely  as  possible. — They  must 
have  such  a  proportion  between 
their  length  and  diameter,  that 
neither  the  ebullition  in  them  may 
become  too  violent,  and  the  water 
be  thereby  ejected  from  them,  nor 
that  they  become  warped  or  made 
crooked  by  the  heat. — They  must 
properly  convey  away  all  the  gene- 
rated steam,  and  be  regularly  sup- 

476 


plied  with  water. — They  most  be 
connected  with  the  main  part  of 
the  boiler  in  such  a  manner,  that 
in  case  of  a  rupture  of  one  of  them, 
the  whole  content   of  water  and 
steam  cannot  suddenly  and  dan- 
gerously  discharge  itself.  —  They 
must  lie  so  deep  under  the  general 
water-level  of  the  boiler  (in  the 
receivers  or  separators),  that  some 
considerable  sinking  of  the  water 
may  be  allowed  to  take  place  with- 
out leaving  'any  of  them  empty ; 
and  in  case  the  latter  effect  should 
occur,  such  tubes  must   first  be 
emptied  as  are  least  exposed  to  the 
heat  of  the  furnace.^— Lastly » they 
must  be  connected  with  each  other 
in  such  manner  that  no  destmctive 
expansion  may  be  allowed  to  take 
place,  and  that  all  may  be  easily 
and  conveniently  cleansed  of  the 
earthy  matters  deposited  in  them. 
The  larger  portions  of  the  boiler, 
or  receivingvessels,  may  themselves 
consist  of  tubes  of  a  larger  diame- 
ter, or  may  form  flat  chambers, 
constructed  of  a  strength  to  with- 
stand a  very  high  pressure  (say 
400  to  500  lbs.  per  square  inch)  : 
this  involves  no  difficulty.     The 
diameter  of  the  receivers  should 
not,  where  it  can  be  avoided,  ex- 
ceed 16  inches,  and  they  should  be 
constructed  of  plate  iron  of  at  least 
f  of  an  inch  thick,  securely  and 
exactly  riveted  together  into  a  cy- 
lin^cal  form.    When  it  is  neces- 
sary that  they  should  be  capadons, 
their  length  should  be  increased, 
and  not  their  diameter  beyond  that 
specified,  or  their  number  should 
be  greater.     Their  covering  hds 
may  be  flat  and  of  cast  iron,  but  of 
considerable  thickness   (li   to  2 
inches),  and  these  must  be  con- 
nected to  the  cylinders  securely, 
and  in  such  a  way  that  they  may 
be  easily  taken  off  when  cleaning 
is  reqmred.    They  must,  under  all 
circumstances,  be  entirely  removed 
from  all  strong  action  of  the  lire, 
and  must  at  most  be  exposed  only 
to  such  currents  as  have  discharged 


-'     '  "      "^^        ^^-S-- 


■^^V       ..*-     — —  .     X *■„  ^ 


TUB 


TUBULAR  BRIDGES. 


TUB 


the  greatest  portion  of  their  heat 
against  the  generating  tnhes.  In 
order  to  preserve  them  from  rust, 
their  internal  and  external  surfaces 
may  be  covered  with  several  coats 
of  oil-vamish,  and  the  coating  re- 
newedy  at  least  on  the  inside,  every 
year. 

Since  these  receivers  or  larger 
parts  of  the  boiler  usually  serve 
as  separators,  and  as  means  of  con- 
nection between  the  generating 
tubes,  they  must  be  perfectly 
adapted  to  fulfil  these  purposes. 
As  separators,  they  must  efficiently 
separate  the  steam  from  the  water, 
so  that  none  of  the  latter  may  pe- 
netrate into  the  working  parts  of 
the  engine;  and  to  this  end  the 
water  surface  in  them  must  be  of 
sufficient  extent.  In  order  that  the 
water  may  not  rise  to  a  dangerous 
height  in  them  by  violent  ebulli- 
tion in  their  tubes,  their  water 
space  must  bear  a  certain  propor- 
tion to  that  of  the  tubes  and  the 
other  parts  of  the  boiler.  The 
steam  room  in  them  must  also  be 
proportioned  to  the  content  of  the 
engine  cylinder ;  so  that  the  press- 
ure may  not  be  too  much  lessened 
by  the  discharge  into  the  engine, 
and  a  foaming  of  the  water  thereby 
be  caused. 
Thibular  Bridges  are  those  in  which 
the  requisite  strength  and  rigidity 
are  obtained  by  disposing  the  mate- 
rials in  the  form  of  a  horizontal 
tube,  through  which  the  passage  is 
formed  for  the  traffic.  They  are 
to  be  distinguished  from  trussed 
bridges,  which,  when  constructed 
of  timber  and  covered  over,  as  in 
several  of  the  American  bridges, 
resemble  a  tube,  or  two  or  more 
parallel  tubes,  being  formed  en- 
tirely without  trussing,  and  there- 
fore admitting  of  construction  vrith 
iron  only.  Tubular  bridges  are  to 
be  regwded  as  an  original  and 
highly  important  invention,  admi- 
rably adapted  for  spanning  wide 
spaces,  and  affording  all  required 
strength  with  a  positive  minimum 


of  depth.  In  all  arched  bridges 
some  portion  of  the  space  below, 
or  head  room  for  navigation,  is  sa- 
crificed by  the  depending  haunches ; 
or,  on  the  other  hand,  if  the  road- 
way is  made  to  correspond  with 
the  chord  of  the  arch,  the  crown  is 
necessarily  elevated  to  a  consider- 
able height,  and  additional  weight 
involved  in  sustaining  and  preserv- 
ing the  position  of  the  higher  parts 
of  the  structure.  Hence  JlatnesMf 
or  the  reduction  of  the  total  depth, 
has  always  been  a  desideratum  in 
the  designing  of  bridges,  and  scien- 
tific skill  andboldness  have  achieved 
several  examples  in  which  this  pro- 
perty is  attained  in  a  much  greater 
degree  than  it  waa  once  thought 
safe  and  prudent  to  attempt.  The 
wrdught-iron  tubular  bridge,  how- 
ever, is  safely  constructed  vrith  a 
total  depth  of  -^th  of  its  span,  and 
with  sufficient  strength  and  rigidity 
to  sustain  great  loads,  such  as  rail- 
way trains,  without  sensible  vibra- 
tion or  deflectiob.  For  bridges  of 
small  span,  the  tubular  principle 
may  be  adopted  in  the  construction 
of  malleable-iron  girders,  each  of 
which  is  itself  a  rectangular  tube 
of  small  section,  the  roadway  being 
thus  supported  upon  two  or  more 
of  these  tubular  girders  arranged 
in  parallel  positions,  and  at  some 
distance  apart.  In  these  bridges 
a  level  roaidway  is  formed  with  a 
small  depth,  but  the  roadway  and 
traffic  occupy  an  additional  depth ; 
whereas  in  the  tubular  bridge,  as 
constructed  for  large  spans,  the 
depth  of  the  tube  itself  comprises 
the  entire  depth  of  the  structure, 
and  it  may  therefore  be  considered 
as  a  vast  hoUow  girder,  through 
which  the  roadway  is  formed.  Mr. 
Robert  Stephenson  appears  to  have 
first  suggested  the  idea  of  form- 
ing tubular  bridges ;  and  that  over 
the  Conway,  erected  on  the  line  of 
the  Chester  and  Holyhead  Railway, 
was  completed  and  opened  in  1849. 
This  bridge  consists  of  two  tubes, 
placed  ptmillel  to  each  other  over 


477 


x5 


TUB 


TUBULAR  BRIDGES. 


TUB 


a  clear  span  of  400  feet.    Each 
tube,  "mth  its  castings,  ttc,  'weighs 
about  1300  tons,  and  is  constructed 
of  plate  iron  riveted  upon  malle- 
able-iron ribs,  the  section  of  the 
tube  being  a  rectangle  about  30  feet 
in  height  and  15  feet  wide.    The 
sides,  top,  and  bottom  of  the  tubes 
consist  of  long  narrow  plates  of 
malleable  iron,  varying  in  length 
up  to  12  feet,  and  in  width  from 
1  foot  9  inches  to  2  feet  4  inches : 
they  vary  in  thickness  from  f  to 
f  inch.    The  internal  ribs  are  of 
T-iron,  3^  inches  deep,  and  placed 
at  intervals  of  2  feet.    A  depth  of 
about  1  foot  9  inches  across  the 
tube  is  occupied  at  top  and  bottom 
with   narrow   cells   formed   with 
plate  iron  and  L-iron  comer  pieces, 
all  firmly  riveted  together.   'These 
cells  are  for  the  purpose  of  giving 
the  requisite  stiffness  to  these  parts 
of  the  tube,  and  are  closer  together 
at  the  top  than  at  the  bottom  of 
the  tube,  as  the  tendency  of  a  load 
is  to  compress  the  upper  part  and 
distend  the  lower  part  of  the  struc- 
ture, and  wrought  iron  is,  it  ap- 
pears, much  better  able  to  resist 
extension  than  compression.     In 
his  report  to  the  Directors  of  the 
Chester    and   Holyhead  Railway, 
their  Engineer,  Mr.  Stephenson, 
thus  referred  to  some  of  the  re- 
sults  of  the   experiments  which 
were  made  in  order  to  determine 
the  form  and  proportions  for  his 
proposed  tubular  bridge  over  the 
Menai  Straits.     ''The  first  series 
of  experiments  was  made  with  plain 
circular  tubes;  the  second  with 
elliptical ;  and  the  third  with  rect- 
angular.     In  the  whole  of  these 
this  remarkable   and  unexpected 
fact  was  brought  to  Ught,  viz.  that 
in  such  tubes  the  power  oif  wrought 
iron  to  resist  compression  was  much 
less  than  its  power  to  resist  ten- 
sion,— being  exactly  the  reverse  of 
that  which  holds  with  cast  iron: 
for  example,  in  cast-iron  beams  for 
sustaining  weights,  the  proper  form 
is  to  dispose  of  the  greater  portion 


of  the  material  at  the  bottom  ade 
of  the  beam ;  whereas  with  vnrought 
iron,  these    experiments    demon- 
strate beyond  any  doubt  that  the  i 
greater  portion   of  the    material  | 
should  be  distributed  on  the  upper  * 
side  of  the  beam.  We  have  arrived, . 
therefore,  at  a  fact  having  a  most  ■ 
important  bearing  upon  the  con- ; 
struction  of  the  tube ;   viz.  that ' 
rigidity  and  strength  are  best  ob- ' 
tained  by  throwing  the   g^reatest 
thickness  of  material  into  the  upper 
side.    Another  instructive   lesson 
which  the  experiments  have  dis-  ■ 
closed  is,  that  the  rectang^ar  tube  ; 
is  by  far  the  strongest,  and  that 
the  circular  and  elliptical  should 
be  discarded  altogether." 

Another  tubular  bridge,  similar 
to  that  at  Conway,  is  now  (1850)  in 
course  of  construction  over  the  Me- 
nai Straits,  near  Bangor,  intended  to 
exceed  the  Conway  bridge  in  ex- 
tent, consisting  of  two  water  bays 
of  460  feet  span  each,  and  two  land 
bays,  one  at  each  end,  of  230  feet ' 
span  each. 

These  grand  bridges  differ  little 
less  in  the  mode  of  constructing 
and  erecting  them  than  in  their 
design  from  ordinary  bridges   of 
stone,  timber,  or  iron.     Thus  the 
larger  tubes  over  the  water-way , 
are  put  together  adjacent  to  their  * 
final  resting-place,  and  when  com- ' 
plete  as  tubes,  they  are  launched 
upon  pontoons,  floated  to  the  piers, 
and  raised  to  their  places  complete 
and  entire  by  hydraulic    presses 
operating  at  each  end.     For  this 
purpose  of  raising,  strong  tempo- 
rary frames  of  cast  iron  are  fitted  , 
to  the  ends  of  the  tube,  and  made 
fast  to  solid  bar-link  chains,  the  I 
upper  ends  of  which  are  forced  up- 
wards by  successive  lifts  of  the 
hydraulic  press,  each  lift  being  6 
feet,  and  the  ends  of  the  tube  being 
packed  up  as  the  raising  proceeds. 
One  end  of  each  tube  is  perma- 
nently laid  upon  cast-iron  rollers, 
to  admit  of  the  changes  of  length 
produced  by  variations  of  tempera-  ■ 


478 


TUD 


TUDOR  STYLE. 


TUD 


ture.    For  the  purposes  of  the  raiU 
way,  transverse  plates  of  iron  are 
fixed  edgewise  on  the  bottom  of 
the  tube,  and  support  longitudinal 
balks  of  timber,  upon  which  the 
rails  are  laid.    The  height  of  the 
Conway  Bridge  is  18  feet  at  the 
bottom  of  the  tubes  above  high 
water;  that  over  the  Menai  Straits, 
called  the  *  Britannia'  Bridge,  102 
feet  above  the  same  level. 
Ihidor  Badges.     The  badges  of  the 
house  of  Tudor  were  either  assumed 
or  derived  from  descent  or  alliance: 
the  red  rose  was  the  peculiar  dis- 
tinction of  the  house  of  Lancaster, 
and  was  borne  by  Henry  VII.  as 
Earl  of  Richmond.    The  portcullis 
was  the  badge  of  the   Beaufort 
branch  of  the  same  family,  assumed 
by  the  descendants    of  John  of 
Ghent,  bom  in  the  castle  of  Beau- 
fort;    and  agreeably  to  heraldic 
simplicity,  a  part  of  the  castle,  its 
most  prominent  feature,  was  depict- 
ed for  the  whole.    The  fleur-de-lis 
was  also  a  badge  of  the  house  of 
Lancaster,  and  was  introduced,  to- 
gether with  the  rose,  in  the  border 
of  Henry's  arms,  as  Earl  of  Rich- 
mond.   Descended  from  Cadwalla- 
der,  the  last  of  the  British  kings, 
and  deriving  from  him  the  name  of 
Tudor,  he  assumed  the  badge  of 
the  red  dragon,  Cadwallader's  en- 
sign.  After  the  battle  of  Bosworth 
Field,  Henry  took  as  a  badge  the 
hawthorn  bush,  crowned,  in  allu- 
sion to  the  circumstance  of  the 
crown  being  found    in   a  hedge, 
whence  it  was  taken  and  placed  on 
his  head.  .  The  red  rose,  or  rose  of 
Lancaster,  he  placed  on  the  sun- 
.  beams,  as  the  white  rose  had  been 
bv  the  head  of  the  house  of  York. 
This  monarch  assumed  the  Tudor 
rose,  or  the  red  rose  charged  with 
the  white,  as  emblematical  of  his 
united  claims  to  the  throne  by 
his  marriage  with  Elizabeth,  the 
daughter  and  sole  heir  of  Edward 
IV.    Upon  the  marriage  of  Prince 
Arthur  with  Catherine  of  Arragon, 
he  adopted,  in  compliment  to  her, 


the  badges  of  her  house.  The  castle 
was  an  ancient  badge  of  the  house 
of  Granada.  The  sheaf  of  arrows 
was  assumed  by  the  house  of  Ar- 
ragon on  the  conquest  of  Gra- 
nada, which  had  been  achieved  by 
the  superiority  of  the  Arragonese 
archers.  .  The  rose  dimidiated  with 
the  pomegranate  was  adopted  as 
being  symbolical  of  the  junction  of 
England  and  Spain.  The  phoenix 
in  flames  was  assumed  by  Edward 
VI.,  in  allusion  to  the  particular 
nature  of  his  birth,  and  was  grant- 
ed by  him  to  the  family  of  Sey- 
mour. A  white  falcon,  crowned, 
and  holding  a  sceptre,  was  assumed 
by  Queen  Anne  Boleyn  as  her  pe- 
culiar badge,  and  was  continued  by 
her  daughter,  Queen  Elizabeth. 
The  harp,  an  ancient  badge  of  Ire- 
land, was  used  by  Queen  Elizabeth. 
The  rose  environed  by  the  garter, 
with  its  motto,  was  a  badge  of 
several  branches  of  the  Tudor 
family.  All  these  badges  were  re- 
presented crowned,  when  borne  by 
the  monarch,  and  were  occasionally 
placed  between  the  royal  sup- 
porters. 
TWor  Style  of  Architecture ^  a  con- 
tinuation of  the  Perpendicular 
Style,  merging  into  a  peculiarity  in 
the  time  of  Henry  VIII.,  when  it 
was  much  applied  to  domestic  pur- 
poses and  to  edifices  for  collegiate 
halls,  and  several  foundations  for 
educationalandcharitable  uses,  thus 
appropriating  the  proceeds  of  mo- 
nastic revenues.  The  mansions  of 
the  Tudor  period  usually  consisted 
of  an  inner  and  base  court,  between 
which  stood  the  gate-house.  The 
principal  apartments  were  the  great 
chamber,  or  room  of  assembly,  the 
hall,  the  chapel,  the  gallery  for 
amusements,  on  an  upper  story, 
running  the  whole  length  of  the 
principal  side  of  the  quadrangle, 
and  the  summer  and  winter  par- 
lours. Of  quadrangular  houses, 
the  seats  of  the  Bishops  of  Car- 
lisle, Cowdry,  Halnaker,  &c.,  may 
be   taken    as  fair  examples.    In 


•^ka^iJ^BIi^b. 


TUG 


TUNNEL. 


TUN 


LamVs  *  Studies  of  Ancient  Houses' 
(a  book  of  a  convenient  size  and 
price)  are  some  fine  examples  in 
this  style,  but  of  a  smaller  kind. 
Very  many  splendid  examples  of 
larger  dimensions  of  halls,  man- 
sions, &c,  still  exist  scattered  over 
the  country.  Linooln'9  Inn  Hall, 
newly  built  in  this  style,  is  the 
most  successful  practice  probably 
that  has  yet  been  accomplished, — 
done  with  all  the  spirit  and  grace 
and  the  picturesque  without  sacri- 
fice of  any  principle  of  this  ad- 
mired style. 

Tufa,  a  calcareous  earth,  composed 
of  broken  and  concreted  sheUs,  or 
the  deposit  from  water  impregnated 
with  lime 

Tuffs,  in  mining,  hoops  of  iron  fasten- 
ed to  the  covers  to  which  the 
tackles  are  affixed 

TuffSf  iieam,  small  steam  vessels  em- 
ployed in  towing  other  craft 

7Wt>  wood,  the  growth  of  the  Bra- 
zils, is  frequently  unsound  in  the 
centre,  very  handsome,  but  soon 
fades:  it  is  used  in  turnery  and 
Tunbridge  ware 

TumbUng-homei  in  nautical  language, 
the  falling  into  midships  of  the 
top-side  above  the  main  breadth, 
to  bring  the  upper  deck  guns 
nearer  the  centre  of  the  ship 

7\immal8,  in  mining,  a  great  quantity 
or  heap 

Tuvnuhu,  a  heap,  or  mound  of  earth, 
sometimes  called  a  burrow,  used 
for  the  burial  of  the  dead  pre- 
vious to  the  Roman  invasion  of 
Britain 

Tunnel,  a  large  and  subterraneous 
arch,  driven  through  an  elevation 
or  hill,  or  under  a  river,  for  the 
passage  of  boats,  carriages,  &c. 

Among  the  costly  and  laborious 
works  of  a  railway,  its  tunnels  oc- 
cupy the  first  place.  Like  mining, 
and  all  other  subterranean  ope- 
rations, the  construction  of  a  tunnel 
can  be  but  little  aided  by  me- 
chanical appliances;  it  chiefly  re- 
quires hard  manual  labour,  exer- 
cised under  circumstances  which 

^80 


do   not  admit  of  that  thorongfaj 
superintendence    which  promotes  j 
economy,  and,  moreover,  liable  to ) 
unforeseen  intemiptions,  of  sor-l 
mounting  which  neither  the  manner 
nor  the  expense    can   be  prede-1 
termined.    Thus  the  Kilsby  tunnel, 
on  the  London  and  Birmin^ism' 
Railway,  was   estimated  to   cost 
about  £  40  per  yard  lineal ;  whereu 
its  actual  cost  vras  iS130  for  the 
same  length,  owing  to  its  inter- 
secting  a   quicksand,  which  the 
trial  borings  had  escaped.    Thus  a ' 
vast  expense  was  necessarily  in-^ 
curred  in  setting  up  and  woricing' 
pumping  machinery   in   order  to 
dry  the  sand.    The  pomps  brouf^t 
up  nearly  2000  gallons  per  minute, 
and  were  working  during  a  period 
of  nine  months.     The  quicksand 
extended  over  a  length  of  aboot 
450  yards  of  the  tunneL    The  Box 
tunnel,  on  the  Great  Western  Rail- 
way, excavated  through  oolite  rock, 
and  being  lined  with  masonry  only 
through  a  portion  of  its  length, 
cost  upwards  of  JSIOO  per  lineal 
yard.    The  Bletchingley  tonnel,  on 
the  South  Eastern  Railway,  cost 
£  72  per  lineal  yard;  and  the  Salt- , 
wood  tunnel,  on  the  same  line  of ; 
railway,  cost  £  1 1 8  per  lineal  yard. 
This  greater  cost  in  the  latter  worik  I 
was  occasioned  by  the  great  body ; 
of  water  in  the  lower  green-sand 
which  the  tunnel  intersects.  j 

The  method  of  proceeding  with  I 
tunnelling  depends   mainly  upon| 
the  kind  of  material  to   be  ex-, 
cavated.    This  having  been  gene-i 
rally  ascertained  by  borings  and! 
trial  shafts,  the  work  is  commenced 
by  sinking  the   working    shafts, 
which  must  be  sufilciently  capsr 
dous  to  admit  readily  of  lowering 
men  and  materials,  raising  the  mi- 
terial  excavated,  fixing  pumps,  sod , 
also  for  starting  the  heading  of  the 
intended  tunnel  when  the  required 
depth  is  reached.   Besides  the  tr^  i 
and  working  shafts,  air-shafts  sre 
sunk  for  the  purpose  of  effecting 
ventilation  in  the  worka  below. 


TUN 


TUNNEL. 


TUN 


The  working  shafts  are  made 
cylindrical,  and  from  8  to  10  feet 
internal  diameter:  9  feet  is  a  fa- 
vourite dimension.  They  are  of 
brick-work,  usually  9  inches  thick, 
and  carried  up  8  or  10  feet  above 
the  surface  of  the  ground,  finished 
with  stone  coping.  These,  and  all 
other  shafts,  rest  upon  curbs  of 
cast  iron,  fitted  into  the  crown  of 
the  tunnel,  and  forming  a  level 
base  for  the  shaft.  The  air-shafts 
are  of  similar  thickness  and  form, 
but  usually  about  3  feet  internal 
diameter.  They  should  not  be 
allowed  to  be  sunk  near  to  the 
working  shaft,  or  at  a  less  distance 
than  50  yards  from  it.  AIL  the 
shafts  are,  of  course,  sunk  on  the 
centre  line  of  the  intended  tunnel. 
In  the  Bletchingley  tunnel,  the 
trial  shafts,  6  feet  diameter  in  the 
clear,  9  inches  thick,  and  35^  yards 
deep,  cost  JS6  per  yard  down 
through  the  Weald  clay.  A  similar 
shaft  in  the  Saltwood  tunnel,  25 
yards  deep,  cost  £  4. 15«.  per  yard 
down,  in  the  lower  green -sand. 
Horse-gins  are  usually  employed 
in  raising  and  lowering  the  ma- 
terials, &c,  and  also  in  drawing 
the  water  up  the  shafts,  unless 
large  pumps  are  used  and  worked 
by  steam-power.  The  engineer  cal- 
culated the  expense  of  horse  labour 
thus  exercised  at  2f  (i.  per  ton 
lifted  100  feet  high,  and  including 
the  boy  to  drive  the  horse. 

The  number  of  working  shafts 
will  depend  chiefly  upon  the  rate 
of  speed  with  which  the  work  is 
required  to  be  accomplished.  With 
plenty  of  men,  horses,  materials, 
and  plant,  the  work  is  much  facili- 
tated by  sinking  extra  shafts,  which 
will  usually  well  repay  their  cost. 
The  Watford  tunnel,  75  chains  in 
length,  on  the  London  and  Bir- 
mingham Railway,  was  specified  to 
be  worked  with  six  shafts,  not  less 
than  8  feet  diameter  within  the 
brick-work,  and  9  inches  thick; 
the  brick-work  moulded  to  fit  the 
circumference  of  the  shaft,  and 

481 


laid  in  two  half-brick  rings;  an 
air-shaft  at  a  distance  of  50  yards 
on  each  side  of  each  working  shaft, 
and  not  less  than  3  feet  6  inches 
diameter  inside ;  the  arch  and  side- 
walls  of  the  tunnel,  usually  two 
bricks  thick,  and  the  invert,  one 
and  a  half  brick,  except  in  places 
where  the  stratum  passed  tlurough 
seemed  to  require  an  increased,  or 
admit  a  diminished  thickness.  The 
form  of  the  top  of  the  tunnel  is 
nearly  semicircular,  supported  by 
curved  side  walls  standing  on  stone 
footings  or  skew-backs,  which  rest 
on  the  invert  forming  the  base  of 
the  tunnel.  The  ends  of  the  tunnel 
are  formed  with  wing-walls.  The 
brick-work  at  the  ends  of  the  tunnel 
is  bound  by  wrought-iron  rods  100 
feet  long,  secured  at  each  end  in  a 
cast-iron  rim  or  plate  built  into  the 
brick-work. 

The  Northchurch  tunnel,  which 
is  16  chains  in  length,  on  the  same 
line  of  railway,  was  worked  with 
two  shafts,  each  9  feet  diameter. 
In  the  construction  of  this  tunnel, 
a  heading  was  driven,  4  feet  wide 
and  5  feet  high,  throughout  the 
entire  length  of  the  tunnel,  and 
between  two  shafts  sunk  for  this 
purpose,  one  near  each  end  of  it. 
It  was  specified  that  this  heading 
should  be  driven  through  before 
any  part  of  the  tunnel  was  com- 
menced, and  supported  and  kept 
open  during  the  execution  of  the 
entire  work  by  sufficient  timbering. 

In  commencing  the  works  of  the 
Saltwood  tunnel,  already  referred 
to,  great  difficulty  was  encoun- 
tered from  the  great  quantity  oi 
water  in  the  lower  green -sand 
which  the  tunnel  intersects.  The 
course  adopted  was  to  make  a 
heading  or  adit  quite  through  the 
hill  on  a  level  with  the  bottom  ol 
the  tunnel,  in  which  the  water  was 
collected  and  drained  off.  The 
size  of  this,  and  of  the  Bletch- 
ingley tunnd,  is  24  feet  wide  a1 
the  broadest  part,  30  feet  including 
the  side  walls ;  25  feet  high  in  the 


TUN 


TUNNEL. 


TUN 


clear,  30  feet  including  the  invert 
and  top  arch,  or  21  feet  clear  above 
the  level  of  rails.  The  brick-work  in 
the  top  arch  and  walls  is  from  two 
and  a  half  to  four  bricks  in  thick- 
ness ;  the  invert  three  bricks  thick. 

When  water  occurs  in  the  sink- 
ing of  the  shafts  or  the  building  of 
a  tunnel,  the  back  of  the  brick- 
work should  be  well  lined  vnth 
puddle,  and  Roman  or  metallic 
cement  substituted  for  mortar. 
The  whole  of  the  Kilsby  tunnel,  on 
the  London  and  Birmingham  Rail- 
way, was  built  in  either  Roman  or 
metallic  cement,  and  the  thickness 
of  the  brick-work  is  chiefly  27 
inches.  This  tunnel  is  about  2423 
yards  long,  and  its  length  is  divi- 
ded by  two  ventilating  shafts,  cy- 
lindrical, and  60  feet  in  diameter. 
These  shafts  are  3  feet  thick  in 
brick-work,  laid  in  Roman  cement 
throughout.  They  intersect  the 
line  of  the  tunnel,  and  thus  form 
curved  recesses  by  that  portion  of 
their  circumference  which  extends 
beyond  the  width  of  the  tunnel  on 
either  side.  These  shafts  were 
built  from  the  top  downwards,  by 
excavating  for  small  portions  at  a 
time,  from  6  to  12  feet  in  length 
and  10  feet  deep. 

The  Box  tunnel,  on  the  Great 
Western  Railway,  intersects  oolite 
rock,  forest  marble,  and  lias  marl, 
with  fullers'  earth.  Eleven  prin- 
cipal shafts,  generally  25  feet  in 
diameter,  and  four  immediate  shafts 
12  feet  6  inches,  were  sunk  for  the 
purpose  of  carrying  on  the  works 
of  this  tunnel,  the  entire  length  of 
which  is  3123  yards,  or  a  little 
more  than  If  mile.  The  section 
of  the  tunnel  was  designed  to  be  27 
feet  6  in.  wide  at  the  springing  of 
invert,  and  30  feet  at  a  height 
of  7  feet  3  inches  above  this ;  clear 
height  above  the  rails  25  feet.  As  a 
great  portion  of  the  tunnel  was  con- 
structed by  mere  excavation,  and 
without  masonry,  these  dimensions 
were  in  some  cases  departed  from, 
in  order  to  clear  away  loose  por- 

482 


tions  of  the  stone  and  secure  solid ' 
surfaces.  Where  biick-woik  is 
used,  the  sides  are  seven  half-brid 
rings  in  thickness,  the  arch  six,  and 
the  invert  four.  During  the  con- 
struction, the  constant  flow  of  wa- 
ter into  the  works,  from  the  name- 
rous  fissures  in  the  rock,  compelled 
pumping  on  a  most  expensive  scale 
to  be  adopted.  From  November, 
1837,  to  July,  1838.  the  worts 
were  suspended,  the  water  having 
gained  so  completely  over  the  steam 
pump  then  employed,  that  the  por- 
tion of  the  tunnel  then  completed 
was  filled  with  water,  as  also  a 
height  of  56  feet  in  the  shafts.  A 
second  pump,  worked  by  a  steam 
engine  of  50  horse-power,  was  ap- 
plied, and  enabled  the  works  to  be 
resumed. 

When  the  working  shafts  are  sunk 
sufiSciently  deep,  a  narrow  heading 
is  excavated,  from  6  to  12  feet  in 
length,  3  or  4  feet  wide,  and  high 
enough  for  a  man  to  work  in.  The 
top  of  this  heading  should  be  so 
much  above  the  intended  soffit  of 
the  tunnel-arch  as  to  admit  the 
thickness  of  the  brick-work,  besides 
the  bars  of  timber  and  boarding  by 
which  the  roof  of  the  heading  is  sap- 
ported,  and  several  inches  should 
be  allowed  for  the  settlement  of  the 
timber,  which  always  occurs  as 
the  excavation  is  proceeded  with, 
and  before  the  brick-work  can  be 
got  in. 

This  allowance  is  of  the  utmost 
importance,  as  without  it  the  brick- 
work will,  when  the  settlement 
occurs,  be  forced  down,  arid  can 
only  be  raised  to  its  proper  IctcI 
by  removing  the  superincumbent 
earth  piecemeal,  and  at  great  cost. 
The  bars,  and  poUng  and  packing , 
boards,  are  introduced  in  the  most 
convenient  manner,  according  to 
the  nature  of  soil  excavated,  and 
the  degree  in  which  it  requires 
support,  or  may  be  safely  left  un- 
supported. 

The  heading  is  extended  on  either 
side  by  first  cutting  narrow  gaps ; 


TUN 


TUNNEL. 


TUN 


horizontally,    or    rather    dipping 
downwards  in  directions  following 
the  intended  form  of  the  tunnel- 
arch.    Into  these  gaps,  crown  bars 
are  laid  lengthwise,  and  supported 
upon  props ;  and  poling  boards  are 
put  in  between  them,  to  retain  the 
earth  at  the  sides  of  the  excavation, 
when  extended.    When  the  head- 
ing has  thus  been  widened  by  ex- 
cavating right  and  left,  and  a  suffi- 
cient length  cleared,  the  centerings 
are  fixed,  and  the  brick-work  is 
commenced.    As  this  proceeds,  the 
earth  is  carefully  rammed  behind 
it,  and  all  vacancies  filled  up,  to 
prevent  any  subsequent  settlement 
of  the  surrounding  earth  upon  it. 
The    crown  bars  which  are   in- 
serted in  the  heading,  and  always 
during  the  excavations,  are    not 
invariably  removed.    If  they  can  be 
drawn  forward  as  the  heading  ad- 
vances, without  disturbing  the  adja- 
cent ground,  and  the  spaces  filled 
up  with  broken  stone,  or  other 
suitable  material,  no  objection  can 
arise ;  but  otherwise  they  should 
be  allowed  to  remain,  and  be  built 
in.     The  whole  of  the  operations 
require  carefully  regulating,  so  that 
none  of  them  shall  advance  too 
rapidly  for   those  which  follow. 
Contractors  are  therefore  usually 
restricted  to  carry  the  excavation 
not  more  than  6  or  8  feet  in  ad- 
vance of  the  brick-work,  or  less,  if 
so  directed  by  the  engineer,  should 
any  change  occur  in  the  strata 
which  he  thinks  may  require  such 
precaution.     When  the  faces  of 
two    contiguous    excavations  ap- 
proach within  about  50  yards  of 
each  other,  a  heading  should  be 
driven  quite  through  the   inter- 
vening ground,  and  the  workings 
joined  before  the  whole  excavation 
and  brick-work  are  proceeded  with. 
Experience  has  proved  that  the 
quality  of  the  bricks  used  in  tun- 
nel-work is  of  the  utmost  import- 
ance.   If  these  contain  lime,  on 
which  the   weather  operates  in- 
juriously, the  face  of  the  work  soon 


decays,  and  requires  extensive  re- 
pair or  restoration.  This  was  the 
case  with  the  Beechwood  tunnel 
on  the  London  and  Birmingham 
Railway,  which  in  less  than  three 
years  was  considered  to  be  in  an 
unsafe  condition,  owing  to  this 
cause.  The  remedy  adopted  was 
of  the  most  complete  character; 
it  consisted  in  an  entirely  new 
lining  of  brick-work,  9  inches 
thick.  This  tunnel  is  about  302 
yards  long,  and  passes  through 
strata  consisting  of  alternate  layers 
of  rock  and  marl,  abounding  with 
springs  of  water.  By  judicious  ar- 
rangement, the  lining  was  com- 
pleted in  forty  days.  The  traffic 
being  diverted  to  one  of  the  two 
lines  of  rails  which  are  laid  in  the 
tunnel,  and  a  hoarding  erected 
along  the  centre,  the  casing  was 
carried  up  on  one  side  to  the 
height  of  4  feet  6  inches  above  the 
springing.  At  this  point  a  course 
of  York  paving,  4^  inches  thick, 
was  bonded  into  the  original  work, 
and  the  new  work  was  securely 
attached  beneath  it  with  wedges 
of  iron ;  half-brick  toothings  were 
also  inserted  in  chases  cut  2  feet 
3  inches  apart  in  the  original  work. 
The  traffic  was  then  turned  into 
the  line  on  the  side  thus  cased,  and 
the  other  wall  was  similarly  treated. 
Bearers  were  then  fixed  6  feet 
apart  over  head,  and  a  dose  floor- 
ing  laid  upon  them.  Upon  each 
bearer  a  pair  of  ribs  was  raised, 
and  keyed  stays  and  laggings  were 
fixed,  and  the  brick-work,  in  En- 
glish bond,  brought  up  on  each 
side  simultaneously,  leaving  a  cen- 
tral space  2  feet  3  inches  wide  at 
the  crown.  A  moveable  centre  of 
this  length  was  used  to  close  in 
this  space  with  two  half-brick  rings. 
Vertical  chases,  4^  inches  square, 
besides  those  cut  for  the  toothings, 
were  made  in  the  face  of  the  old 
walls  previous  to  lining.  These 
formed  permanent  drains,  termi- 
nating in  the  culvert  beneath  the 
centre  of  the  tunnel. 


483 


TUR 


TURBINE  WHEEL. 


TCUl 


Ttwbine  Water-wheel,  The  hori. 
Eontal  -water-wheel  so  caUedi  as 
used  in  France  and  Germany^  was 
invented  by  M.  Fonmeyron:  the 
water  enters  at  the  centre,  and, 
diverging  from  it  in  every  di. 
rection,  it  then  enters  all  the 
backets  simoltaneoosly,  and  passes 
off  at  the  external  circumference 
of  the  wheeL  The  pressure  with 
which  the  water  acts  on  the 
backets  of  the  revolving  wheel  is 
in  proportion  to  the  vertical  column 
of  water,  or  heights  of  the  fiill, 
and  it  is  conducted  into  these 
backets  by  fixed  curved  gurders  se- 
cured upon  a  platform  within  the 
circle  of  the  revolving  part  of  the 
machine.  The  efflux  of  the  water 
is  regulated  by  a  hollow  cylindrical 
sluice,  to  wUch  stops  are  fixed, 
which  act  together  between  the 
guides,  and  are  raised  or  lowered 
by  screws  that  communicate  with 
a  governor,  so  that  the  opening  of 
the  sluice  and  stops  may  be  en- 
larged or  reduced  in  proportion  as 
the  velocity  of  the  wheel  requires 
to  be  accelerated  or  retarded.  Tur- 
bines may  be  divided  into  high" 
pressure  and  low-pressure  engines. 
High-pressure  turbines  are  par- 
ticularly available  in  situations  such 
as  often  occur  in  hilly  districts 
where  high  falls  of  water  may  be 
commanded,  and  the  character  of 
the  site  affords  facilities  for  con- 
structing reservoirs,  so  that  a  con- 
stant supply  may  be  insured.  In 
these  cases  the  height  of  the  co- 
lumn of  water  will  compensate  for 
the  smallness  of  its  volume,  and 
the  high-pressure  turbine  will  be 
found  applicable  with  great  ad- 
vantage to  the  grinding  of  com, 
crushing  ores,  working  threshing 
machines,  or  actuating  other  ma- 
chinery. The  low-pressure  tur- 
bines produce  great  effect  with  a 
head  of  only  nine  inches,  and  are 
suitable  for  situations  in  which  a 
large  bulk  of  water  fiows  with 
little  faU.  The  results  of  an  in- 
vestigation  by  MM.  Arago,  Prony, 

484 


Gambey,  and  Savary,  who  were 
appoint€Ml  by  the  Fk«nch  Academe ' 
des  Sciences  to  report  upon  tor-' 
bines,  are  given  in  a  treatise  by  j 
M.  Morin  on  the  subject,  and  ue  ] 
as  follows :  \ 

1.  That  these  wheels  aie  sppli- 
cable  equaUy  to  great  and  to  small 
falls  of  water.  2.  That  they  tnos- 
mit  an  useful  efibct,  equal  to  from 
70  to  78  per  cent,  of  the  absolate 
total  moving  force.  3.  That  they 
may  work  at  very  different  vdo- 
dties,  above  or  below  that  cor- 
responding to  the  maximiim  effect, 
without  the  useful  eflfect  vaiying 
materially  from   that    maximoiD. 

4.  That  they  may  work  frrom  one 
to  two  yards  deep  under  water, 
without  the  proportion  which  the 
useful  effect  bears  to  the  total 
force  being  sensibly   diminished. 

5.  In  consequence  of  the  last  fin- 
ceding  propoiy,  they  utilize  at  all 
times  the  greatest  possible  propor- 
tion of  power,  as  they  may  be 
placed  below  the  lowest  levels  to , 
which   the  water  surface    sinks. 

6.  That  they  may  receive  very  ts-  ' 
riable  quantities  of  water  vritfaont 
the  relation  of  the  useful  effect  to 
the  force  expended  being  mate- 
rially lessened.  < 

The  practical  value  of  these  ma- 1 
chines  is  most  obvious  when  they  I 
are  applied  to  small  falls  of  water.  \ 
Smeaton's  experiments  proved  that 
with  a  high  fall  in  whidi  an  over- 
shot water-wheel   can  be    intro-l 
duced,  80  per  cent,  of  the  original ! 
moving  power  may  be  realized. , 
And  there  is  little  doubt,  accord- 1 
ing  to  Riihlman,  whose  treatise  on , 
turbines  has  been  so  well  trans- 
lated and  edited  by  Sir  Robert  | 
Kane,   that  where    an    overshot 
wheel,  or  a  wheel  with  tolerably , 
high  breasts  and  overfoll  aluices, , 
can  be  erected,  they  are  to  be  pre- ' 
ferred  to  the  turbine,  except  there  | 
is  much  back-water  to  contend 
against,  when  the  turbine  may  be 
sunk  to  a  considerable  depth  in 
the  back-water  without  any  mate- 


TUR 


TURBINE  WHEEL. 


TUR 


rial  loss  of  its  power.  Eyen  in 
oases  which  admit  the  working  of 
overshot  wheels,  the  peculiar  ap- 
plicability of  the  turbine,  which 
affords  a  direct  horizontal  motion 
to  the  working  of  corn-mills,  should 
command  full  consideration  before 
it  is  relinquished  in  favour  of  the 
overshot  wheeL  In  every  case  of 
fall,  either  higher  than  that  suit- 
able for  an  overshot  wheel,  or 
lower  than  that  required  for  such  a 
breast-wheel  as  just  described,  the 
turbine  decidedly  deserves  the  pre- 
ference. Smeaton  proved  that  un- 
dershot wheels  realized  only  30  per 
cent,  of  the  original  force. 

In  falls  of  great  height,  the  ve- 
locity of  the  machine  is  so  rapid 
that  it  may  be  applied  to  spinning 
machinery  without  mill-work,  or 
with  very  little,  to  produce  the 
required  speed.  The  turbine  in 
its  present  form  is  of  compara- 
tively modem  date;  the  experi- 
ments of  M.  Foumeyron,  which 
resulted  in  its  invention,  having 
been  commenced  in  1823,  and  the 
first  machine  was  erected  in  1827. 
In  tracing  this  form  of  water-moter 
to  its  elements,  however,  the  con- 
trivance which  is  known  as  Dr. 
Barker's  mill,  must  necessarily  be 
noticed.  This  machine,  which  is  of 
very  old  date,  consists  of  an  up- 
right pipe  or  tube,  which  revolves 
on  a  vertical  axis,  and  is  formed 
with  an  open  funnel-shaped  top, 
and  closed  at  the  bottom,  from 
which  project  two  horizontal  hol- 
low arms  or  pipes.  These  arms 
are  closed  at  their  outer  ends,  but 
have  each  a  round  hole  near  the 
extremity,  and  so  placed  that  the 
two  holes  are  opposite  to  each 
other.  The  upright  pipe  is  kept 
filled  with  water,  which  flows  into 
the  funnel-shaped  top.  The  issu- 
ing of  the  water  from  the  holes  on 
opposite  sides  of  the  horizontal 
arms  causes  the  machine  to  re- 
volve rapidly  on  its  axis,  with  a 
velocity  nearly  equal  to  that  of  the 
effluent  water,  the  force  being  in 


proportion  to  the  hydrostatic  press- 
ure which  is  exerted  by  the  ver- 
tical column,  and  to  the  area  of 
the  apertures;  there  being  no  solid 
surface  at  the  hole  on  which  the 
lateral  pressure  can  exert  itself 
while  it  is  acting  with  its  full 
force  on  the  opposite  side  of  the 
arm.  This  unbalanced  pressure  is, 
according  to  Dr.  Robison,  equal  to 
the  weights  of  a  column  having 
the  orifice  for  its  base,  and  twice 
the  depth  under  the  surface  of  the 
water  in  the  trunk  for  its  height. 
If  the  orifice  were  closed,  the 
pressure  upon  it  would  equal  the 
weights  of  a  column  reaching  to 
the  surface;  but  when  open,  the 
water  issues  with  a  velocity  nearly 
equal  to  that  acquired  by  falling 
from  the  surface,  and  the  quantity 
of  motion  which  is  produced  is 
that  of  a  column  of  twice  this 
length  moving  with  this  velocity. 
The  revolution  of  the  machine 
causes  the  water,  which  having  de- 
scended the  vertical  pipe  moves 
along  the  arms,  to  partake  of  the 
drciUar  motion,  thus  producing  a 
centrifugal  force  that  is  exerted 
against  the  ends  of  the  arms  of 
the  machine.  According  to  the 
laws  of  motion,  this  force  increases 
in  proportion  to  the  square  of  the 
distance  from  the  centre  at  which 
it  is  developed.  Thus  the  velocity 
of  the  efflux  is  increased,  and  also 
the  velocity  of  revolution.  But  as 
the  circular  motion  has  to  be  im- 
parted to  every  particle  of  water 
as  it  enters  the  horizontal  arm, 
which  is  done  at  the  expense  of 
the  motion  already  acquired  by 
the  arm,  there  is  a  limit  to  the 
velocity  even  of  an  unloaded  ma- 
chine. Barker's  mill  has  been 
treated  of  by  Desaguliers,  Euler, 
John  Bemouilli,  and  M.  Mathon  di 
la  Cour,  the  latter  of  whom  pro* 
posed,in  1 775,  to  bring  down  alargf 
pipe  from  an  elevated  reservoir 
to  bend  the  lower  part  of  it  np< 
wards  and  attach  to  it  a  shorl 
pipe  with  two  arms,  like  Barker'i 


485 


TUR 


TURBINE  WHEEL. 


Tim 


mill  reversed,  and  revolving  in  like 
manner  upon  a  vertical  spindle; 
the  joint  of  the  two  pipes  being 
contrived  so  as  to  admit  of  a  free 
circular  motion  mthout  much  loss 
of  water.  By  this  arrangement  a 
fall  of  any  extended  depth  may  be 
made  aviiilable.  An  improved  form 
of  Barker*s  mill  was  patented  sub- 
sequently by  Mr.  Whitelaw,  in 
which  the  modifications  suggested 
by  M.  M.  de  la  Cour  were  partly 
included,  and  a  peculiar  form  given 
to  the  horizontal  arms,  adapted  to 
preserve  the  centrifugid  force  from 
loss  or  counteraction. 

In  this  mill  the  two  arms  form 
the  letter  S,  the  water  being 
emitted  from  their  extremities  in 
the  direction  of  the  circle  traced 
by  their  revolution,  the  sectional 
capacity  of  the  arms  increasing  as 
they  approach  the  centre  of  rota- 
tion, so  as  to  contain  a  quantity 
of  water,  at  each  section  of  the' 
arm,  inversely  proportional  to  its 
velocity  at  that  section. 

With  a  well-made  model  of  this 
mill,  the  patentee  obtained  an 
effect  equal  to  73*6  per  cent,  of 
the  power  employed,  and  nearly 
equal  results  are  said  to  have  been 
realized  in  actual  practice.  The 
following  particulars  of  the  height 
of  fall  and  useful  effect  produced 
with  turbines,  already  erected  on 
the  Continent,  will  tend  to  show 
their  increasing  value  in  proportion 
to  the  heights  of  the  acting  co- 
lumn of  water. 


Heights 
&U  in  feet. 

Useful  effect 
per  cent. 

of  power 
employed. 

7- 

71- 

63 

75 

79 

87 

126 

81 

144 

80 

In  1837  a  turbine  water-wheel 
was  erected  by  M.  Foumeyron, 
an  account  of  which  is  here 
quoted  from  Mr.  Joseph  Glynn's 

486 


Report  to  the  British  Association 
for  the  Advancement  of  Science  in 
1847.  This  turbine  is  "erected 
at  St.  Blasier,  or  Blaise,  in  the 
Black  Forest  of  Baden,  for  a  fall 
or  column  of  water  of  72  feet 
(22  metres).  The  wheel  is  made 
of  cast-iron  with  wrought -iron 
buckets ;  it  is  about  20  inches  in 
diameter,  and  weighs  about  lOSfts.: 
it  is  said  to  be  equal  to  56  horses' 
power,  and  to  give  an  useful  effec- 
equal  to  70  or  75  per  cent,  of  the 
water-power  employed.  It  driTes 
a  spinning- mill  belonging  to  M. 
d'Eichtal.  A  second  turbine,  at 
the  same  establishment,  is  worked 
by  a  column  of  water  of  10^ 
metres,  or  354  feet  high,  which  i$ 
brought  into  the  machine  by  cast- 
iron  pipes  of  18  inches  diameter  of 
the  local  measare,  or  about  161 
inches  EngUsh.  The  diameter  of 
the  water-wheel  is  14i,  or  about 
13  inches  English,  and  it  is  said 
to  expend  a  cubic  foot  of  water 
per  second:  probably  the  expen- 
diture may  be  somewhat  more  than 
this.  The  width  of  the  water- 
wheel  across  the  face  is  '225,  or 
less  than  a  quarter  of  an  inch.  It 
makes  fr^m  2200  to  2300  revolu- 
tions per  minute ;  and  on  the  eod 
of  the  spindle,  or  upright  shaft  of 
the  turbine,  is  a  bevelled  pinion  of 
nineteen  teeth,  working  into  two 
wheels  on  the  right  and  left,  each 
of  which  has  300  teeth :  these  p^t 
motion  to  the  machinery  of  the  fac- 
tory, and  drive  8000  water-spindlo. 
roving  -  frames,  carding  -  engines. 
cleansers,  and  otheraccessories.  The 
useful  effect  is  reported  to  be  from 
80  to  85  per  cent,  of  the  theo- 
retical water-power.  The  water  is 
filtered  at  the  reservoir  before  it 
enters  the  conduit-pipes ;  and  it  i-< 
important  to  notice  this,  since  the 
apertures  of  discharge  in  the  water- 
wheel  are  so  small  as  to  be  easily 
obstructed  or  choked." 
Turbith  or  Tuvpith  mineral,  (Qwen* 
yellow j)  is  subsulphate  of  mercury, 
of  a  beautiful  lemon  yellow  colour. 


TUR 


TURF. 


TUR 


but  so  liable  to  change  by  the  action 
of  light  or  impure  air,  that,  not- 
withstanding it  has  been  some- 
times employed,  it  cannot  be  used 
safely,  and  hardly  deserves  atten- 
tion as  a  pigment 
2\i.rf  is  generally  found  in  bogs,  in 
horizontal  layers  from  10  to  30 
feet  in  thickness ;  sometimes  in  the 
form  of  a  blacldsh-brown  mud; 
sometimes  it  is  a  dark  peaty  mass, 
and  often  a  combination  of  roots 
and  stalks  of  plants:  frequently 
the  turf  layers  interchange  with 
layers  of  sand  or  clay.  Sea-water 
is  better  adapted  to  the  formation 
of  turf  than  rain  or  spring  water. 

Turf  is  simply  dug  with  spades, 
and  then  dried.  If  too  moist, 
the  semi-fluid  mass  is  piled  upon 
a  dry  spot,  and  there  left  until 
the  water  leaks  off,  and  until  the 
mass  appears  dry  enough  to  be 
formed  into  square  lumps  in  the 
form  of  bricks.  In  many  instances, 
however,  the  freshly  dug  turf  is 
triturated  under  revolving  edge- 
wheels,  faced  vdth  iron  plates  per- 
forated all  over  their  surface: 
through  the  apertures  in  these 
plates  the  turf  is  pressed  tiU  it 
becomes  a  kind  of  pap,  which  is 
put  into  a  hydraulic  press,  and 
squeezed  until  it  loses  the  greater 
part  of  its  moisture:  it  is  then 
dried  and  charred  in  suitable  ovens. 
The  charcoal  made  in  this  way  de- 
serves the  notice  of  the  artisan. 

The  component  parts  of  turf  dif- 
fer from  those  of  wood.  This  dif- 
ference is  owing  to  the  fact  of  its 
being  decomposed  woody  fibre. 
The  following  is  an  analysis  of 
several  specimens: 

One  hundred  parts  of  good  turf 
contained,  besides  ashes, 

Carbon.  Hydrogen.  Oxygen. 
I.     5703      5-63      31-76 
II.     5809      6-93      31-37 
III.    57-79      6-11      30-77 

The  charring  of  turf  is  far  more 
easily  effected  than  the  charring  of 
wood,  partly  on   account  of  its 

487 


square  form,  partly  on  account  of 
its  chemical  composition.  In  pits, 
the  charring  of  turf  is  not  difficult, 
if  the  same  method  is  pursued  as 
that  adopted  in  the  charring  of 
wood ;  but  channels  or  draft-holes 
must  be  left  in  the  kiln,  because 
the  square  pieces  pack  so  closely, 
that,  without  this  precaution,  suffi- 
cient draught  would  not  be  left  to 
conduct  the  fire.  Turf  is  generally 
found  in  considerable  masses  in 
one  spot;  therefore  the  erection 
of  char-ovens  is  no  object  of  mere 
speculation,  but  affords  all  the  ad- 
vantages of  a  permanent  establish- 
ment. 
TumbidTs  blue  {ferricyanide  of  iron.) 
Professor  GrsQiam's  account  of  this 
variety  of  Prussian  blue  is  nearly 
as  follows :  It  is  formed  by  adding 
ferricyanide  of  potassium  (red  prus- 
siate  of  potash)  to  a  protosidt  of 
iron:  it  results  from  the  substi- 
tution of  three  equivalents  of  iron 
for  three  equivalents  of  potas- 
sium. The  same  blue  precipitate 
may  be  obtained  by  adding  to  a 
protosalt  of  iron  a  mixture  of  yel- 
low prussiate  of  potash,  chloride 
of  soda,  and  hydrochloric  acid. 
The  tint  of  this  blue  is  lighter  and 
more  delicate  than  that  of  Prus- 
sian blue.  It  is  occasionally  used 
by  the  calico-printer,  who  mixes  it 
vnth  perchloride  of  tin,  and  prints 
the  mixture,  which  is  in  a  great 
measure  soluble,  upon  Turkey  red 
cloth,  raising  the  blue  colour  after- 
wards by  passing  the  cloth  through 
a  solution  of  chloride  of  Ume,  con- 
taining an  excess  of  hme.  The 
chief  object  of  this  operation  is  to 
discharge  the  red  and  produce 
white  patterns,  where  tartaric  acid 
is  printed  upon  the  cloth ;  but  it 
has  also  the  effect  incidentally  of 
precipitating  the  blue  pigment  and 
peroxide  of  tin  together  on  the 
cloth,  by  neutralizing  the  chlorine 
of  the  perchloride  of  tin.  This 
blue  is  believed  to  resist  the  action 
of  alkalis  longer  than  ordinary 
Prussian  blue. 


TUR 


TURNING  TOOLS. 


TUR 


Iktmer's  yeUoWy  CanelyettoWf  Patent 
yellow.  This  is  an  oxychloride  of 
lead,  which  may  be  prepared  by 
different  processes :  when  litharge 
or  the  protoxide  of  lead  is  acted 
upon  by  a  solution  of  common 
salt,  there  are  formed,  soda,  which 
remains  dissolved,  and  a  white  com- 
pound, which  is  hydrated  ozychlo- 
ride  of  lead ;  and  this,  when  heated, 
loses  water,  becomes  of  a  yellow 
colour,  and  is  the  compound  re- 
quired. It  is  composed  neariy  of 
one  part  of  chloride  and  nine  p^irts 
of  oxide  of  lead :  it  may  also  be 
obtained  by  heating  chloride  and 
oxide  of  lead  together  in  the  requi- 
site proportions,  or  by  heating  a 
mixture  of  one  part  of  hydrochlo- 
rate  of  ammonia  with  ten  parts  of 
protoxide  of  lead.  In  fusing  these 
compounds  it  is  requisite  to  be  ex- 
tremely carefdl  to  avoid  any  ad- 
mixture of  carbonaceous  or  com- 
bustible matter,  as  that  would 
reduce  a  portion  of  the  oxide  of 
lead  to  its  metallic  state,  which 
would  injure  the  c<^our  of  the 
product. 

Turning  toob.  These  are  of  two 
classes,  viz.  hand-tools  and  tools 
fixed  in  the  slide-rest.  Of  the 
former,  the  principal  are  the  heel- 
tool,  graver,  planisher,  gouge,  and 
chisel:  there  are  many  others  which, 
however,  are  but  modifications  of 
these,  and  are  required  only  in 
particular  cases. 

The  slide-rest  tools  are  distin- 
guished by  the  same  names  as  the 
hand-tools,  but  vary  from  them 
slightly  in  the  forms  of  their  cut- 
ting parts,  which  in  the  hand-tools 
are  in  general  rather  broader,  in 
order  that  the  part  to  be  cut  away 
may  be  acted  on  as  long  as  possible 
before  shifting  the  tool ;  for  forward 
motion  is  in  their  case  continuous 
only  for  the  short  period  while  the 
cutting  edge  can  be  brought  to 
bear  on  the  material  without  shift- 
ing  forward  the  resting  point  of 
the  tool.  The  face  or  front  edge 
of  the  tool  should  in  every  case  be 


( 


nearly  perpendicular  to  the  hori 
zontid  diameter  of  the  work,  bot ! 
a  small  difference  is  xequiredforl 
clearance. 

The  angle  of  the  cutting  edgei 
should  be  more  or  less  acute,  ac- 1 
cording  to  the  nature  of  the  mate- 
rial to  be  turned ;  in  general,  the 
softer  and  more  uniform  the  mite- 
rial,  the  more  acute  shoold  be  tbe 
angle :  for  wood,  it  should  be  very 
acute,  and  for  iron  and  steel  less 
acute.  The  velocity  with  which 
tbe  work  is  made  to  revolve  most 
also  be  adapted  to  the  mateiial, 
and  must  be  such  that  the  tool  may 
take  the  greatest  eflfect  consistent 
with  the  preservation  of  its  cutting 
edge. 

The  hardening  and  tempering  of 
turning  tools  require  much  expe- 
rience on  the  part  of  the  workman; 
for  although  they  may  be  of  the 
best  possible  shape,  they  are  worse 
than  useless  unless  properly  hard- 
ened. The  general  pn>oess  of 
hardening  and  tempering  tools  ii 
as  follows :  The  cutting  end  of  the 
tool  is  slowly  heated  in  a  dear  fire, 
and  when  of  a  light  red  heat  is 
cooled  quickly  in  water;  it  is  then 
very  hard  and  brittle,  and  requires 
tempering  or  reducing  to  the  pro- 
per degree  of  hardness :  to  effect 
this,  it  is  necessary  to  brighten  the 
part,  so  that  a  change  of  colour 
may  be  readily  observed,  and  then 
place  it  upon  a  red-hot  bar ;  when ' 
it  has  become  heated  to  a  certain ' 
degree  by  contact,  the  bright  part 
will  have  a  pale  straw  colour ;  this  \ 
gradually  deepens,  and  when  it  has 
arrived  at  the  requisite  depth  of 
tint,  the  tool  is  removed  and  again 
cooled,  after  which  it  is  fit  for 
use.    (See  also  the  article  Toolt.) 

Tumeole,  a  kind  of  colour  used  in 
painting 

Tum-tabki  &  circular  table,  with 
cross-rails  fixed  on  its  surfrtce,  sup- 
ported by  rollers,  and  capable  of 
being  turned  on  a  central  pivot 
used  for  moving  a  railway  carriage 
from  one  line  of  rails  to  another 


» I 


488 


TUR 


TUYERES. 


TUY 


Turret,  a  small  tower  attached  to 
and  forming  part  of  another  tower, 
or  placed  at  the  angles  of  a  church 
or  public  buildingi  especially  in  the 
style  of  Tudor  architecture 

Tuscan  Style  of  Architecture,  This 
originated  in  the  north  of  Italy,  on 
the  first  reyival  of  the  arts  in  the 
free  cities,  and  beyond  which  it  has 
never  yet  travelled,  except  in  some 
examples  which  were  introduced 
by  Inigo  Jones  in  the  first  church 
of  St.  Paul,  Covent  Garden,  and  by 
Sir  Christopher  Wren  in  porticoes 
at  St.  Paul's  cathedral,  London. 
This  style  is  characteristic  of  the 
people  who  practise  it.  The  Tus- 
can, it  has  been  said,  should  pe- 
culiarly be  adopted  in  England. 

Tuyeres.  Before  puddling  became 
so  generally  introduced,  the  shape 
and  position  of  the  tuyere  at  a  blast- 
furnace received  considerable  atten- 
tion,but  since  the  quality  of  pig  iron 
has  been  sought  for  with  but  little 
anxiety,  these  have  ceased  to  be  con- 
sidered of  much  importance.  The 
chief  purpose  of  the  metallic  tuyere 
is  the  preservation  of  the  fire-proof 
hearthstones;  the  direction  and 
form  of  the  blast  are  of  minor  im- 
portance. This  protection  is  ac- 
complished, in  some  measure,  by 
making  a  coating  of  fire-clay  in  the 
tuyere -hole  which  is  cut  in  the 
hearthstones.  By  this  means,  con- 
stant attendance,  and  repeated  re- 
newal with  clay,  the  tuyere  may 
be  maintained  narrow:  whether 
formed  of  clay  or  metal,  it  should 
never  be  wider  than  the  nozzle. 
Where  one  of  the  former  kind  ex- 
ceeds the  width  of  the  nozzle,  it 
bums  away,  and  the  earth  is  ex- 
posed to  destruction.  The  preser- 
vation of  the  original  dimensions 
of  the  hearth  is  the  main  object 
which  the  manager  of  a  furnace 
seeks  to  secure;  and  as  the  clay 
tuyere  does  not  efiPect  this  object, 
those  made  of  copper  or  cast  iron 
have  been  substituted  in  its  place. 
These  reach  further  into  the  fur- 
nace than  those  of  clay,  and  there- 

489" 


fore,  as  it  is  decidedly  of  advantage 
that  the  blast  should  be  driven  as 
far  as  possible  into  the  centre  of  the 
hearth,  the  former  are  much  pre- 
ferable to  the  latter.  If  formed  of 
wrought  iron,  they  are  liabletobum, 
as  the  iron,  in  consequence  of  its 
purity,  oxidizes,  and  forms  with  the 
clay  around  it  a  very  fusible  silicate, 
which  is  precipitated  into  the  fur- 
nace. Gray  is  preferable  to  white 
cast  iron,  and  also  to  wrought  iron ; 
the  carbon  and  impurities  it  con- 
tains protect  it  against  oxidation 
and  destruction.  Copper  is  the 
best  metal  for  tuyeres ;  it  is  a  good 
conductor  of  heat,  and  is  kept  cool 
by  the  blast  more  easily  than  iron. 
Its  silicates  also  are  infusible.  If 
copper  oxidizes,  and  forms  a  silicate, 
the  latter  will  protect  it.  The  ad- 
vantages derived  from  the  copper 
tuyere  have,  in  Europe,  been  ac- 
knowledged for  more  than  a  cen- 
tury; still  the  charcoal  furnaces 
in  America,  at  which  cold  blast 
is  employed,  are  generally  blown 
by  clay  tuyeres,  the  result  of  which 
is  the  waste  of  much  coal,  and  the 
production  of  inferior  iron.  This 
is  mentioned  as  one  of  those  rare 
cases  in  which  Americans  do  not 
make  the  best  use  of  the  means 
at  their  disposal.  The  copper 
tuyere  is  protected  against  the  heat 
of  the  furnace  by  the  cold  blast, 
which  touches  it,  and  for  this  rea- 
son should  not  be  wider  than  the 
nozzle.  In  this  point  of  view,  it 
may  be  regarded  merely  as  a  pro- 
longation of  the  nozzle,  and  is,  of 
course,  governed  by  the  rules  appli- 
cable to  the  latter.  So  long  as  pig 
iron  is  to  be  made  by  the  charcosd 
forge,  the  desire  to  tiake  white 
plate  iron  in  the  blast-fiimace  will 
exist.  It  is  very  difficult,  almost 
impossible,  to  keep  a  blast-fumaoe 
constantly  running  upon  a  certain 
kind  of  iron ;  and  therefore  the  dif- 
ference which  the  quality  of  that  in 
the  furnace  exhibits  is  modified  to 
a  more  or  less  general  standard  by 
means  of  the  position  of  the  tuy^. 


TUY 


TUYERES. 


TUY 


such  as  its  direction  and  inclina- 
tion. Very  skilful  management  is 
required,  in  many  instances,  to  pro- 
duce the  desired  effect.  In  some 
parts  of  Europe,  where  cold -blast 
iron  for  the  forge  is  manufactured, 
the  copper  tuyere  is  yet  in  use; 
but  where  pig  iron  for  puddling 
is  made,  or  hot  blast  employed, 
such  close  attention  is  not  ne- 
cessary. In  America,  the  niceties 
involved  in  adjusting  the  tuyere 
can  scarcely  be  appreciated,  not 
even  at  the  forge  fires;  but  this 
adjustment  is  unaccompanied  vnth 
any  practical  convenience,  as  the 
trouble  it  requires  is  never  com- 
pensated. The  advantages  which 
arise  from  a  scrupulous  attention 
are,  at  best,  very  small ;  and  such 
attention  would,  under  the  condi- 
tions which  exist  in  America,  es- 
pecially the  high  price  of  labour, 
result  in  loss  instead  of  gain. 

At  cold-blastfurnaces,in  America, 
clay  or  cast  iron  tuyeres,  principally 
the  former,  are  consequently  gene- 
rally employed.  Water  tuylres  are 
in  use  at  forges,  fineries,  hot-blast, 
and  at  some  cold -blast  furnaces. 
A  common  one  for  the  Catalan 
forge,  the  charcoal  forge,  finery, 
and  charcoal  blast-furnaces,  is  made 
of  boiler  plate.  The  top  part  is 
hollow,  while  the  bottom  part, 
which  is  generally  flat,  is  solid.  A 
water-pipe,  of  ^-inch  bore,  con- 
ducts a  current  of  cold  water 
through  the  hollow  top :  this  pre- 
serves the  tuyere,  and  protects  it 
against  burning.  The  bottom  is 
made  flat,  so  as  to  serve  as  a  sup- 
port to  the  nozzle;  and  thus  the 
latter  may  be  readily  moved  to  those 
places  where  it  is  most  needed. 
At  blast-furnaces  and  fineries,  this 
precaution  is  not  of  much  use,  as 
the  nozzle  remains  at  the  place 
where  it  is  fixed ;  but  at  forges  it 
must  be  moveable.  Both  of  the 
water-pipes  are,  in  most  cases,  at 
the  top  ;  but  this  arrangement  can 
scarcely  be  considered  so  advan- 
tageous as  though  one  pipe,  or  the 

490 


entrance  of  the  water,  were  nearer 
the  bottom,  and  the  other  pipe,  or 
the  outflow,  at  the  top. 

Tuyeres  for  anthracite,  coke,  and 
most  of  the  charcoal  furnaces,  are 
perfectly  round,  and  made  of  boiler 
plate;  seldom  of  copper  or  cast 
iron.  The  tapering  of  them  doe^ 
not  affect  the  furnace ;  and  for  all 
the  evil  this  tapering  occasions,  it 
may  be  a  peifect  cylinder.  In 
using  hot  blast,  it  makes  do  difler- 
ence  how  the  air  is  conducted  into 
the  furnace,  provided  the  tuyere  is 
kept  open,  and  bright;  which  is  all 
that  is  necessary.  The  nozzle  is 
laid  into  the  tuyere, — how  far  it 
reaches  into  it,  is  a  matter  of  do 
consequence, — and  the  space  be- 
tween them  filled  up  with  day. 
At  a  cold-blast  fiimace,  it  reqiurs 
some  attention  not  to  push  the 
nozzle  too  far  in,  or  to  draw  it  too 
far  back.  The  water-pipes  are  of 
lead,  f-inch,  seldom  l-inch  bore: 
one  on  the  lower,  and  the  other  on 
the  top  part  of  the  brim.  The 
lower  pipe  conducts  the  water  to 
the  tuyere,  and  the  upper  one^m 
it.  The  former  is,  in  many  cases, 
pushed  as  far  as  possible  into  its 
interior,  to  bring  the  cold  water 
into  the  furnace ;  and  the  water  is  | 
thus  appUed  where  the  heat  is  i 
greatest.  A  constant,  munterrapted  , 
supply  is  necessary  to  prevent  the 
melting  of  the  tuyere.  The  water 
must  be  pure ;  else  it  will  leave  a 
sediment  in  it  which  is  sure  to 
cause  its  destruction.  There  must, 
also,  be  a  sufilcient  supply  of  cclii 
water:  if  the  formation  of  steam 
is  going  on  in  the  interior  of  the 
tuyere,  the  latter  is  sure  to  be 
iburned.  Copper  and  brass  last 
longer  than  iron;  but  if  iron 
tuyeres  are  well  made,  and  sol- 
dered with  copper,  and  if  there  is 
no  lack  of  water,  they  may  last  a 
long  time.  Where  there  is  a  de- 
ficiency of  water,  or  where  there 
are  sediments  in  the  interior  of  a 
tuyere,  a  few  hours'  heat  will  de- 
stroy it.    If  it  be  found  that  thet 


ruY 


TUYEKES. 


do  not  wear  well,  attention  must 
be  directed  to  the  water;  and  if 
nothing  appears  wrong,  the  appli- 
cation of  larger  pipes,  or  higher 
hydrostatic  pressure,  will  then  re- 
medy the  evil.  Water  tuyeres  are 
generally  from  10  to  20 inches  long ; 
those  that  are  too  short  are  liable 
to  be  burnt,  by  the  fire  working 
around  them,  because  there  is  not 
sufficient  room  to  keep  it  closed 
up.  Another  disadvantage  is,  that 
their  want  of  length  prevents  them 
firom  being  pushed  into  the  hearth; 
but  length  is  necessary  when  the 
earth  is  burned  out,  and  when  the 
blast  should  be  carried  further  into 
the  interior.  The  external  size  is 
also  a  matter  which  requires  atten- 
tion in  the  construction.  The  total 
surface  determines  the  amount  of 
water  which  is  necessary.  The 
larger  the  surface,  particularly  the 
diameter,  the  greater  the  amount 
of  water  necessary,  and  of  course 
the  greater  the  danger  of  burning. 
A  tuyere  is  seldom  more  than 
four  inches  in  diameter  inside ;  but 
ibfi  diameter  outside  is  sometimes 
twelve,  and  even  more  inches.  With 
such  an  increase  of  the  diameter, 
however,  the  danger  is  augmented. 
Tuyeres^may  be  considered  a  pro- 
longation of  the  nozzle  or  the  blast- 
pipe,  and  disconnected  from  it 
merely  for  the  sake  of  preservation, 
and  of  more  convenient  access  to 
the  interior  of  the  furnace.  Those 
for  cold  blast  should  taper  mor^ 
than  those  for  hot  blast,  because 
the  former  clinker  in  a  greater  de- 
gree, and  require  cleaning  more 
frequently  than  the  latter.  The 
more  acute  the  angle  of  the  tuyere, 
the  colder  it  works ;  and  the  more 
tapered  it  is,  the  hotter  it  works. 
These  observations  are  of  practical 
importance.  In  most  cases  the 
blast  is  required  as  far  in  the  in- 
terior of  the  furnace  as  possible, 
because  fuel  is  thus  saved,  better 
iron  produced,  and  the  hearth  pro- 
tected. There  is  some  difficulty 
in  giving  cold-blast  tuyeres  a  slight 


TUY 

taper,  because  they  should  be  verv 
wide  outside ;  but  this  difficulty  can 
be  overcome  by  making  their  in- 
teriors more  curved.  Iftheextmne 
end,  as  far  back  as  the  diameter  of 
the  month,  is  cyUndrical,  the  same 
purpose  is  accomplished  as  though 
the  whole  were  cylindrical.    If  too 
much  tapered,  which  is  shown  by 
its  working  too  hot,  the  evil  is 
diminished,  in  some  measure,  by 
pushing  the  nozzle  further  into  the 
furnace.    This  is  but  a  temporary, 
not  a  radical  remedy;  and  a  tuyere 
of  a  proper  form  must  be  substi- 
tuted.    If  it  works  too  cold,  that 
is,  sets  on  too  much  cold  cinder, 
the  only  resource  is  scrupulously 
to  keep  it  clean,  and  to  replace  it 
as  soon  as  possible  by  one  more 
tapered,  or  with  a  more  obtuse 
cone.    From  these  considerations, 
it  is  evident  that  different  kinds 
of  ore  require  a  tuyere  of  different 
taper ;  but  for  the  exact  degree  of 
this  taper  no  general  rule  can  be 
given.     Experience  must,  in  this 
instance,  be  the  only  guide.    This 
will  appear  more  evident  on  taking 
into  consideration  the  kind  of  fuel 
and  the  pressure  of  the  blast  re- 
quired.   Calcareous  ore,  as  well  as 
the  pig  iron  made  from  it,  works 
naturally  hot  at  the  tuyere ;  conse- 
quently, those  more  acute  are  em- 
ployed, and  serve  to  drive  the  blast 
far  into   the   furnace,  by  which 
means  they  are  kept  cool.     This 
result  can  be  effected  by  a  water 
tuyere.     Clay  ores,    which  work 
naturally  cold,  work  better  with 
one  that  is  tapered.    These  consi- 
derations, which  have  a  special  bear- 
ing upon  the  working  of  furnaces 
and  forges,  are  entirely  of  a  practi- 
cal nature ;  and  for  this  reason  the 
management  of  the  furnace  or  forge 
is  accompanied  with  such  different  I 
results.    It  is  evident  that  the  mo- 
dification of  a  tuyere  cannot,  at 
times,  be  so  quickly  accomplished 
as  may  be  desired :  months,  and 
even  years,  are  often  consumed, 
before  the  required  form  can  he  I 


491 


TUY 


TUYERES. 


TTT 


accurately  detemiiiied ;  in  many 
cases,  this  form  is  never  arrived  at. 
The  shape  is  therefore  a  matter 
which,  at  blast-furnaces,  generally 
depends  on  the  decision  of  the 
keeper  or  founder;  and  as  those 
formed  of  clay  may  be  altered  very 
conveniently,  this  may  be  assigned 
as  one  of  the  reasons  why  so  many 
of  that  kind  are  in  use.  The  whole 
matter,  however,  is  divested  of  its 
mystery  when  it  is  found  that  an 
obtuse  tuyere  tends  to  work  warm, 
while  one  more  acute  produces  an 
opposite  effect,  and  is  more  advan- 
tageous as  respects  both  the  quality 
and  quantity  of  work ;  but  it  is  more 
difficult  to  manage.  The  form  of 
the  nozzle,  as  well  as  that  of  a 
metal  tuyere,  is  permanent;  and 
as  the  advantage  of  either  shape 
can  be  arrived  at,  in  a  more  or  less 
perfect  manner,  by  pushing  in  or 
drawing  back  the  nozzle,  no  solid 
objection  exists  againstthoseformed 
of  metal.  Some  difference  should  be 
made  between  the  form  of  the  nozzle 
and  that  of  the  tuyere.  A.n  obtuse 
nozzle  should  work  with  the  latter 
more  acute;  a  slightly  tapered 
nozzle,  with  one  greatly  tapered. 
The  latter  form  is  generally  pre- 
ferred, on  account  of  the  facility  of 
cleaning. 

In  applying  hot  blast,  the  form 
of  the  tuydre  and  the  nozzle  is  a 
matter  of  indifference ;  but  in  their 
construction  it  is  found  desirable 
to  adopt  the  rules  here  suggested. 
The  advantages  of  hot  blast  are 
sometimes  doubtful;  and  it  is 
therefore  better  to  unite,  by  means 
of  perfect  forms  of  apparatus,  all 
the  advantages  derivable  from  the 
cold  blast,  and  thus  to  regain  what 
is  lost  in  quantity  by  its  employ- 
ment. 

In  forge  fires  there  are  generally 
but  one  tuyere  and  two  nozzles. 
At  refinery  fires  the  tuyeres  are 
often  all  on  one  side;  at  other 
places  on  opposite  sides.  All  these 
differences  are  the  result  of  local 
causes,  originating  in  the  form  of 

492  "  '.  ~~ 


the  apparatus,  the  quality  of  the 
iron  and  fuel,  the  pressure  of  the 
blast,  and  the  quahfication  of  the 
workmen.  Their  number  and  thai 
position  in  the  blast -fiunsce  d6 
serve  attention.  In  using  cold 
blast,  few  should  be  employed,  tnd 
in  using  hot  blast  as  many  ss  pos- 
sible. Cold-blast  tuyeres  are  natu- 
rally troublesome ;  they  are  apt  to 
become  black,  and  require  oonstui 
attention,  as  well  in  moving  the 
nozzle  as  in  patching  them  irith 
clay;  they  also  tend  to  product 
white  iron,  and  they  cool  the  lover 
parts  of  the  hearth.  For  theie 
reasons  their  number  should  be 
reduced  as  much  as  possible,  u 
the  hot-blast  tuyere  works  very  hot, 
occasions  but  little  trouble,  is  mocii 
inclined  to  produce  gray  iron,  vA 
tends  to  reduce  silex,  and  conse- 
quently to  produce  a  poor  qoality 
of  iron.  Therefore,  the  use  of  as 
many  hot-blast  tuyeres  as  can  be 
conveniently  employed  is  recom- 
mended. The  position  of  tuyeres 
is  most  favourable  when  placed  on 
both  sides  of  the  hearth.  Tbetiicp 
is  that  part  of  the  hearth  which  ii 
first  burnt  out ;  and  if  the  torat 
Is  in  the  back  part  of  the  hearth. 
the  distance  from  it  to  the  o^ 
posite  timp  is  unnecessarily  in- 
creased. 

Tying,  in  mining,  the  term  for  wash- 
ing ores 

Tympan  of  an  arch,  a  triangular  sptcc 
or  table  in  the  comers  or  sides  of 
an  arch,  usually  hollowed,  and  en- 
riched with  branches  of  laorel, 
olive,  oak,  &c.,  and  sometimes  with 
emblematical  figures 

Tyn^Mtnum,  the  triangular  panel  of 
the  fastigium  of  any  building,  com- 
prehended between  its  corona  in<l 
that  of  the  entablature :  the  panels 
of  a  framed  door  were  called  ty*- 
pana  by  the  Romans 

Typhoon  is  a  name  frequently 
to  a  tropical  storm :  it  is  tito  given 
to  the  hot  winds  which  occasion- 
ally blow  with  great  violence  in 
Africa,  Syria,  Arabia,  and  PersU 


ULT 


UNDERSHOT  WHEELS. 


UNI 


and  which  are  felt,  though  rarely 
and  with  much-diminished  force, 
in  the  southern  parts  of  Italy  and 
Spain.  The  sirocco  of  Egypt  and 
the  coasts  of  the  Mediterranean, 
the  simoom  of  Arabia,  and  the  har- 
mattan  of  the  coast  of  Guinea,  are 
understood  to  be  so  many  desig- 


nations of  the  typhoon;  all  of 
them  being  supposed  to  originate 
in  the  same  cause,  with  modifi- 
cations depending  merely  on  the 
nature  of  the  particles  exhaled 
from  the  ground  in  the  diflferent 
countries.  Tliey  aie  also  wi^L  to 
cause  YratcLspouta  at  %ea. 


ULT 

Ultramarine,  LazultM,  or  Azures  is 
prepared  from  the  lapis  lazuli^  a 
precious  stone  found  principally  in 
Persia  and  Siberia.    It  is  the  most 
celebrated  of  all  modem  pigments, 
and,  from  its  name  and  attributes, 
is  probably  the  same  as  the  no  less 
celebrated  Armenian  blue,  or  cy. 
anus  of  the  ancients.    Of  the  lat- 
ter,  Theophrastus  informs  us  that 
the  honour  of  inventing  its  factiti- 
ous preparation  (by  perhaps  a  very 
singular  chemico-mechanical  pro- 
cess still  used  for  ultramarine)  was 
ascribed  in  the  Egyptian  annals  to 
one  of  their  kings ;  and  it  was  so 
highly  prized,  that  the  Phoenicians 
paid  their  tribute  in  it,  and  it  was 
given  in  presents  to  princes :  hence 
it  was  a  common  practice,  in  those 
times,  to  counterfeit  it. 

Ultramarine  ashes  (mineral  gray)  are 
the  residue  of  lapis  lazuli  from 
which  ultramarine  has  been   ex- 
tracted, and  vary  in  colour  from 
dull  gray  to  blue.    Although  not 
equal  in  beauty,  and  inferior  in 
strength  of  colour,  to  ultramarine, 
they  are  extremely  useful  pigments, 
affording  grays  much  more  pure 
and  tender  than  such  as  are  com- 
posed of  black  and  white,  or  other 
blues,  and  better  suited   to  the 
pearly  tints  of  flesh,  foliage,  the 
grays  of  skies,  the  shadows  of  dra- 
peries, &c.,  in  which  the  old  masters 
were- wont  to  employ  them.    Ul- 
tramarine broken  with  black  and 
white,  &c.,  produces  the  same  ef- 
fect, and  is  thus  sometimes  car- 
ried throughout  the  colouring  of  a 
picture.    The  brighter  sorts  of  ul- 


UNI 

tramanne  aahea  an*  m^ 

pale  ultramarines,  LdTtbT^^'' 

of  blue;    the  i^erifr  L^^'l^Z' ' 
mineral  gray.  ^"^^ 

Umber,  commonly  called  Jlaw  Umber 
18  a  natural  ochre,  abounding  with 
oxide  of  manganese,  said  to  have 
been  first  obtained  from  ancient 
Umbna,  now  Spoleto,  in  Italy,    it 
18  found  also  in  England,  and  in 
most  parts  of  the  worid ;  but  that 
which  IS  brought  from  Cyprus,  un- 
der the  name  of  Turkish  umber,  is 
the  best.     It  is  of  a  brown  citrine 
colour,  semi-opaque,  has   all   the 
properties  of  good  ochre,  is  per- 
fectly durable  both  in  water  and 
oil,  and  one  of  the  best  drying  co- 
lours we  possess:    it   injures    no 
Other  good  pigment  with  which  it 
may  be  mixed. 
Undecagon,  a  polygon  of  eleven  sides 
Undercroft,  a  subterraneous  apart- 
ment or  crypt 
Underlay,    "When  a  vein  in  a  mine 
hides  or  inclines  from  a  perpendi- 
cular line,  it  is  said  to  underlay 
Underlay  shaft,  a  shaft  sunk  on  the 

course  of  a  lode 
Underlayer,  in  mining,  a  perpendi- 
cular shaft  sunk  to  cut  the  lode  at 
any  required  depth 
Undershot  wheel,    in   hydraulics,   a 
wheel  with  a  number  of  fiat  boards, 
which  receive  the  Impulse  of  the 
water  conveyed  to  the  lowest  part 
of  the  wheel  by  an  inclined  canal 
Uniform  motion.     The  velocity  of  a 
moving  body  is  said  to  be  uniform 
when  the  body  passes  over  equal 
spaces  in  equal  times 
Union  screws  or  Joints,  in  locomotive 


493 


UNI 


VACUUM. 


zw 


engines,  the  brass  unions  for  con- 
necting tlie  elastic  bore-pipe  of  the 
tender  to  the  feed-pipe  of  the  en- 
gine; smaller  ones  also  connect 
the  tender  steam -pipe  with  the 
feed-pipe  and  with  the  boiler.  The 
feed-pipe  is  likewise  attached  to 
the  lower  end  of  the  pump  by  a 
large  union  screw. 
Unit  of  work.  The  measure  of  any 
amount  of  work  is  the  work  done 
where  a  pressure  of  1  ib.  is  exerted 
through  1  foot,  the  pressure  acting 
in  the  direction  in  which  the  space 
is  described.  If,  instead  of  lib. 
being  moyed  through  1  foot,  it  be 
moTcd  through  2  feet,  it  is  clear 
that  the  work  is  doubled,  or  that 
two  units  of  work  have  been  done. 
The  difference  between  the  aggre- 
gate work  done  upon  a  machine 
during  any  time  by  those  forces 
which  tend  to  accelerate  the  mo- 
tion, and  the  aggregate  work,  dur- 
ing the  same  time,  of  those  which 
tend  to  retard  the  motion,  is  equal 
to  the  aggregate  number  of  units 
of  work  accumulated  in  the  moving 
parts  of  the  machine  during  that 
time,  if  the  former  aggregate  ex- 
ceed the  latter,  and  lost  by  them 
during  that  time,  if  the  former  ag- 
gregate fall  short  of  the  latter. 

In  reference  to  the  unit  of  tune, 
the  unit  of  mechanical  power  has 
been  assumed  to  be  1  lb.  raised  1  ft. 
high,  and  1  minute  as  the  unit  of 
time ;  the  unit  of  work  will  there- 
fore be  represented  by  1  tb.  raised 


1  foot  high  in  1  minute.  Now,  it 
is  assumed  that  a  horse  is  capable 
of  doing  33,000  such  units  of  woik, 
i.  e.  that  he  is  capable  of  raising 
33,000  lbs.  1  foot  high  in  a  minntc, 
or  1  lb.  33,000  feet  high ;  and  tfaii 
is  called  a  horte'g  power,  and  ii 
the  unit  of  work  in  reference  to 
the  unit  of  time  commonly  used  ii 
this  country. 

IMivenal  chuck,  a  circular  plate  to 
screw  on  the  mandril  of  a  lathe, ; 
and  hold  a  nut  or  any  small  piece! 
of  metal  to  h^  bored :  in  the  plate  | 
are  two  or  more  radial  slots,  fitted 
by  the  jaws  or  pieces  which  pro- 
ject from  the  face  of  the  chuck, 
moved  by  screws  towards  the  cen- ; 
tre,  and  tightened  upon  the  nut 

Unmoor,  in  navigation,  to  reduce  i 
ship  to  the  state  of  riding  by  a 
single  anchor  and  cable 

Ufuhyji,  to  remove  any  thing  out  of 
a  ship 

Urn,  an  ancient  utensil,  used  for  a  i 
variety  of  purposes ;  sometimes  as 
the  receptacle  of  lots  or  for  votes  j 
at  the  public  election  of  magis-| 
trates;  but  its  greatest  and  most! 
frequent  use  was  as  a  receptacle ! 
for  the  ashes  of  the  dead  after  their  i 
bodies  were  burnt.  These  urns  were  | 
sometimes  kept  in  houses,  and  also  j 
put  under  tombstones,  or  within! 
vaults  or  graves.  Urns  and  simUar  I 
vessels  have  been  found  in  the  bu- 
rial-places of  the  ancient  Britons. 
In  modem  times,  the  urn  is  an 
utensil  of  domestic  use. 


VAC 

Vacuum,  a  vacuity  or  space  unoccu- 
pied by  matter;  in  pneumatics, 
the  vacuum  caused  by  an  air-pump, 
which  is  a  degi'ee  of  rarefaction 
sufficient  to  suspend  the  ordinary 
effects  of  the  atmosphere. 

Vacuum-pump,  a  pump  connected  to 
the  boiler  of  a  marine  engine,  for 
charging  the  boiler  with  water 
from  the  sea  by  discharging  the  air, 

494 


VAL 

causing  the  water  to  rise  vfithin  the 
boiler,  from  the  inressure  of  the 
atmosphere  without :  by  tlus  means  i 
much  labour  and  time  are  saved,' 
which  would   otherwise   be  ex- 
pended in  lifting  the  vats  | 

Vair,  a  term  in  heraldry,  being  a  for 
composed  of  four  distinct  coloun ; 
argent,  gules,  or,  and  sable 

Vahe,  in  hydraulics,  &c,  a  lid  con- 


VAL 


VAPORIZATION. 


VAP 


trived  to  open  one  way,  to  admit  a 
fluid  into  a  tube,  but  which  shuts 
when  pressed  from  the  other,  to 
prevent  its  return.  In  anatomy,  a 
kind  of  membrane  which  opens  in 
certain  vessels  to  admit  the  blood, 
and  shuts  to  prevent  its  regress. 
Valves,  in  blast  machines,  are  essen- 
tial in  blast-conducting  pipes ;  first, 
for  shutting  up  the  blast  entirely ; 
secondly,  for  diminishing  and  in- 
creasing it  at  pleasure.  The  first 
kind  is  needed  where  the  blast  is 
generated,  for  various  purposes,  by 
the  same  blast  machine.  The 
valves  in  use  are,  the  sliding,  the 
conical,  and  the  trundle.  The 
two  first  named  are  but  little  em- 
ployed. If  well  made,  the  latter 
kind  of  valve  is  very  usefuL  At 
one  end  it  has  a  handle,  and,  in 
many  instances,  a  graded  scale, 
which  indicates  the  amount  of  air 
which  passes  through  the  valve,  or, 
in  other  words,  it  shows  the  open- 
ing of  the  valve.  At  each  tuyere 
or  nozzle  a  valve  is  required,  which 
serves  ather  to  shut  off  the  blast 
entirely,  or  to  regulate  the  passage 
of  whatever  amount  is  needed.  At 
the  nozzle-valve,  a  scale  is  very 
useful,  partly  for  the  purpose  of 
adjusting  the  blast,  and  partly  for 
that  of  fastening  the  handle  of  the 
valve,  and  keeping  it  in  a  certain 
position. 

The  laws  which  govern  the  con- 
struction of  blast-pipes,  valves,  and 
tuyeres,  are  summarily  as  follows: 
The  interior  of  the  blast  conductors 
should  be  as  smooth  as  possible, 
as  an  uneven  surface  causes  great 
friction.  The  friction  of  the  air  is 
proportional  to  the  length  of  the 
pipe,  and  to  the  density  of  the  air 
which  passes  through  it.  It  is 
proportional  to  the  square  of  the 
speed  of  the  air,  and  the  reverse  of 
the  square  of  the  diameter  of  the 
pipe.  Obstructions  caused  by 
short  bends  in  such  pipes  are 
inversely  proportional  to  the  angle 
of  the  bend,  and  are  governed 
by  the  laws  of  hydrostatics.    Sud- 

495 


den  contractions  and  expansions 
of  the  pipe  occasion  a  whirling 
disturbance  in  the  current  of  the 
air — a  loss  of  power,  or,  what 
is  the  same,  of  blast. 

VdhCt  the  tafetyi  in  pneumatics,  a 
valve  in  a  steam  engine,  to  obviate 
the  danger  of  explosion,  by  allow- 
ing the  steam  to  escape  when  the 
pressure  is  raised  beyond  a  certain 
weight 

Vaiveseatf  the  flat  or  conical  surface 
upon  which  a  valve  rests 

Vandyke  Brown,  a  pigment  hardly 
less    celebrated    than    the    great 
painter  whose  name  it  bears,  is  a 
species  of  peat  or  bog-earth,  of  a 
fine  deep  semi-transparent  brovm 
colour.    The  pigment  so  much  es- 
teemed and  used  by  Vandyke  is 
said  to  have  been  brought  from 
Cassel ;  and  this  seems  to  be  justi- 
fied  by   a  comparison  of  Cassel 
earth  with  the  browns  of  his  pic- 
tures.    The  Vandyke  browns   in 
use  at  present,  appear  to  be  terrene 
pigments  of  a  similar  kind,  purified 
by  grinding  and  washing  over:  they 
vary  sometimes  in  hue,  and  in  de- 
grees of  drying  in  oil,  which  they 
in  general  do  tardily,  owing  to  their 
bituminous  nature,  but  are  good 
browns  of  powerful  body,  and  are 
durable  both  in  water  and  oil. 

Vane,  or  Wmd^vane,  in  navigation,  a 
thin  slip  of  bunting;  a  string  of 
feathers,  &c,  stuck  up  to  wind- 
ward, to  show  the  direction  of  the 
wind 

Vanet*  In  Europe,  the  custom  of 
placing  vanes  on  church  steeples  is 
very  old ;  and,  as  they  were  made 
in  the  figure  of  a  cock,  they  have 
been  thence  denominated  weather- 
cocks. 

Vannmg,  removing  the  impurities 
from  tin  ore 

V(gMrization,  The  presence  of  mois- 
ture in  the  air  is  accounted  for  by 
a  modification  of  the  process  of 
vaporization.  Water  evaporates,  or 
is  converted  into  steam  (by  steam 
we  here  mean  the  elastic  vapour  of 
water,  which  is  always  invislUe; 


VAP 


VAPORIZATION. 


VAP 


what  is  oommonly  called  steam, 
but  property  cloud,  is  liquid  water 
in  a  finely  divided  or  powdered 
state,  wafted  like  dust  by  currenu 
of  air  or  of  steam,  properly  so 
called,)  at  all  temperatures,  until 
the  whole  space  above  it,  whether 
containing  air  or  not,  is  pervaded 
with  watery  vapour  of  a  certain  fix- 
ed density  and  elasticity,  depend- 
ing on  the  temperature,  and  con- 
nected therewith  by  certain  laws. 
The  elasticity  or  expansive  ten- 
dency of  a  fluid  is  estimated  by  the 
number  of  pounds  or  ounces  with 
which  it  presses  on  each  square 
inch  of  surface  that  it  touches ;  or 
by  the  number  of  inches  of  mer- 
cury that  it  win  support,  as  on  a 
barometer. 

Steam  can  exist  at  any  given 
temperature,  and  of  such  density  as 
to  have  a  certain  fixed  pressure, 
and  no  more;    and  (if  there  be 
vrater  enough  present)  steam  v«rill 
be  accumulated  till  it  has  this  den- 
sity ;  but  no  more  can  then  be  ac- 
cumulated without  raising  the  tem- 
perature: and  if  the  temperature 
be  lowered,  a  portion  of  the  steam 
vnll  immediately  become  water,  so 
that  (occupying  in  this  state  some 
thousands  of  times  less  space  than 
before)  it  may  leave  room  for  the 
remaining  vapour  to  expand,  till 
its  expansive  force  is  reduced  to 
that  which  the  new  temperature 
can    support.      The   pressure    of 
steam  is,  therefore,  always  the  same 
at  the  same  temperature.    At  212^ 
its  elastic  force  is  equal  to  that  of 
the  atmosphere,  and  it  will  support 
a  column  of  mercury  30  inches 
high,  which  is  the  reason  that  boil- 
ing requires  this  temperature  in  the 
open  air,  when  the  barometer  is  at 
30  inches ;  but  rather  less  or  more, 
when  the  barometer  stands  lower 
or  higher.  Above  this  temperature 
it  becomes   high-pressure  steam, 
which  at  220*^  will  support  nearly 
35  inches  of  mercury;   at  230^ 
nearly  42  inches,  and  so  on.    But 
the   steam  which  is   thrown  off 

496 


from  the  vraters  of  the  earth,  firom 
damp  S(ril,firom  the  folii^  of  plants, ' 
and  even  from  ice  and  snow,  his 
but  a  very  small  pressure.  Steun 
at  32®  will  support  only  0*200  d 
an  inch  of  mercury :  at  40®,  0*263 , 
of  an  inch ;  at  50®,  0*375  of  an  inch; ; 
at  60®,  0*524,  or  rather  more  tbao  ■ 
half  an  inch  of  mercury ;  at  8(f , ' 
it  will  support  one  inch,  and  so  oil 
When  the  air  contains  as  much 
vapour  as  can  exist  at  the  existing 
temperature,  it  is  said  to  be  satu-  j 
rated.  If  in  this  state  it  experieoce  { 
the  smallest  reduction  of  tempera- 
ture, some  of  the  vapour  must  im- 
mediately become  liquid,  assmmn; 
the  form  of  cloud,  fog,  or  tuil 
These  effects  depend  on  the  cool- 
ing of  the  air  below  the  tempen- 
ture  necessary  to  retain  aU  its, 
vapour.  But  when  a  solid  body  is 
cooled  below  this  temperature, 
(the  air  remaining  aboye  it,)  a  dif- 
ferent kind  of  deposition  ocean, 
called  dew,  which  does  not  fall  in 
drops  from  the  air,  but  grows,  as  it 
were,  on  the  solid.  Dr.  "WeUs 
proved,  by  a  most  complete  inres- 
tigation  of  this  subject,  that  instead 
of  dew  cooling  bodies,  as  commonly 
supposed,  it  is  their  cooling  whicb 
causes  dew ;  and  its  formation  even 
mitigates  the  cold,  by  the  heat  pre- 
viously latent,  which  the  steun 
gives  out  on  condensing  into  water. 
The  degree  of  heat  at  which  dev 
begins  to  be  formed  is  called  the 
dew-point,  and  instruments  called 
hygrometers  have  been  invented  to 
measure  it.  The  difference  between 
the  temperature  of  the  dew-point 
and  the  temperature  of  the  atmo- 
sphere indicates  the  degree  of  dry- 
ness, which  in  this  country  seldom 
reaches  30®;  that  is,  the  tempera- 
ture of  the  earth  necessary  to  con- 
dense the  vapour  of  the  air  is  seldom 
30®  below  the  temperature  of  the 
air.  In  India  it  has  been  known 
to  be  61®  below  it,  and  in  Africa 
probably  lower  stiU. 

If,  while  dew  is  forming,  the 
earth  continues  to  cool  down  until 


VAR 


VELOCIPEDE. 


VEL 


it  reaches  the  freezing-point,  hoar- 
frost is  formed.  The  beautifrQ 
fig^ores  seen  in  winter  on  the  inner 
surface  of  window  panes,  cooled 
by  the  external  air,  are  produced 
by  these  cold  surfaces  condensing 
the  moisture  of  the  warmer  air 
within. 

Varryf  a  term  in  heraldry,  denoting 
the  mixture  of  argent  and  azure 
together 

Varry  cuppy,  a  term  applied  to  a  frir 
of  cups 

Vatf  a  wooden  tub,  used  to  wash  ores 
and  mineral  substances  in ;  a  work- 
ing-tub of  any  kind 

Vault,  in  architecture,  an  arched  roof, 
so  contrived  as  that  the  several 
stones  by  their  disposition  shall 
support  each  other 

Veering,  or  Wearing,  in  navigation, 
the  operation  to  which  a  ship,  in 
changing  her  course  from  one 
board  to  the  other,  turns  her  stem 
to  windward,  in  opposition  to  tack- 
ing, wherein  the  bow  is  turned  to 
the  wind  and  the  stem  to  lee- 
ward 

Vein,  a  course  of  metal  in  a  mine : 
a  rake  vein  is  perpendicular,  or 
nearly  so ;  a  pipe  vein,  nearly  hori- 
zontsd 

Vein,  in  mining,  to  wash  or  cleanse  a 
small  portion  of  ore  in  a  shoal 

Velocimeter,  an  apparatus  for  measur- 
ing the  rate  of  speed  of  machinery. 
When  the  velocity  is  uniform,  the 
instrument  is  merely  a  measurer 
of  distance ;  but  this  is  not  the  case 
vidth  a  variable  velocity,  which  re- 
quires a  much  more  elaborate  con- 
trivance for  its  estimation.  Such 
avelocity-measurer  was  constrocted 
by  Breguet,  of  Paris,  under  the  di- 
rection of  M.'Morin,  the  principle 
of  which  may  be  briefly  explained  as 
follows :  A  circular  disc,  covered 
vrith  card  or  paper,  is  made  to  re- 
volve vrith  an  uniform  motion  by 
means  of  clock-work,  regulated  by 
air- vanes:  upon  this  disc,  a  re- 
volving pencil,  whose  motion  is 
caused  by  and  corresponds  with 
that  of  the  body  whose  variable 

497 


velocity  is  to  be  measured,  describes 
a  curved  line ;  and  from  this  curve, 
which  results  fit>m  a  combination 
of  the  variable  vrith  the  unifr>rm 
motion,  the  velocity  may  be  easily 
ascertained  by  processes  and  for- 
mvilie  adapted  to  the  p\xrpo«e.  One 
of  these    cards,  with  the    cxirve 
traced  on  it  by  the  piston  of  the 
Cornish  steam  engine  at  Old  Ford 

It  !T?rf  1"  *^^  *  Transactions  of 
the  British  Associatioi,  for  the  Ad 

vancement  of  Science,'  This  beau- 
tiful and  ingenious  contnvance,  by 
which  spaces  described  in  the  ten- 
thousandth  part  of  a  second  may 
be  easily  discerned,  is  the  invention 
of  M.  Poncelet,  and  was  carried 
into  execution  by  M.  Morin. 

The  instrament,  when  put  in 
order,  was  first  tried  at  King's  Col- 
lege,London,  a  variablemotionbeing 
given  by  a  small  carriage  made  to  de- 
scend  an  inclined  plane.  The  cor- 
respondence  of  the  velocity  shown 
by  the  machine  vrith  that  deduced 
by  the  known  laws  of  dynamics, 
was  such  as  to  give  great  confidence 
in  its  accuracy.  After  a  few  minor 
alterations,  suggested  by  frequent 
trials,  it  was  removed  to  the  East 
London  Water-Works,  and  attached 
to  the  Cornish  engine  at  work 
there,  from  which  several  diagrams 
were  taken ;  and  the  velocities  cal- 
culated from  these  have  been  ex- 
pressed in  the  form  of  geometrical 
curves,  whose  abscissae  represent 
the  spaces  passed  over  by  the  pis- 
ton of  the  engine,  and  whose  ordi- 
nates  indicate  the  corresponding 
velocities  at  the  diflferent  points  of 
the  stroke. 

Velocy>ede,  a  carriage  which  is  capa- 
ble of  being  propelled  along  a  road 
by  the  muscular  power  of  the  rider 
acting  upon  treadles  and  levers 
which  communicate  with  a  cranked 
wheel  axle 

Velocity,  in  dynamics,  is  the  ratio  of 
the  quantity  of  linear  extension 
that  has  been  passed  over  in  a 
certain  portion  of  time;  or  it  is 
the  ratio  of  the  time  that  has  been 


VEL 


VELOCITY. 


VEL 


employed  in  moving  along  a  deter- 
minate extension. 

When  a  man  ascends  verti- 
cally, his  velocity  is  reduced  to 
abont  one -half  of  his  horizontal 
velocity,  indicating  that  he  acts 
against  a  double  resistance ;  there- 
fore, when  a  man  ascending  a 
ladder,  carries  a  load,  the  maximum 
effect  will  take  place  when  his 
ascending  velocity  is  about  one- 
fourth  of  the  velocity  he  can  walk 
horizontally  without  a  load. 

A  man  of  ordinary  strength  will 
not  be  able  to  walk,  unloaded,  at  a 
quicker  rate  than  3i  miles  an  hour, 
if  this  exertion  is  to  be  continued 
for  10  hours  every  day.  Indeed, 
those  who  examine  the  subject 
with  a  view  to  a  fetir  average,  will 
find  this  to  be  about  the  extreme 
velocity  that. can  be  continued, 
without  injury,  for  any  considerable 
time;  therefore  a  man  ought  to 
move  with  half  this  velocity  to 
produce  a  maximum  effect;  that 
is,  at  the  rate  of  1}  mile  an  hour, 
which  is  about  2^  feet  per  se- 
cond. 

But  this  supposes  the  whole  load 
to  be  the  useful  effect,  whereas 
part  of  it  must  consist  of  the  ap- 
paratus employed  to  carry  it,  or  the 
friction  of  the  intermediate  ma- 
chine, or  other  circumstances  of  a 
like  nature.  About  one-fifth  of 
the  velocity  may  be  considered 
equivalent,  at  an  average,  to  the 
force  lost  in  friction,  &c.,  in  all 
cases ;  in  many  it  will  exceed  one- 
fifth.  Hence  the  maximum  of  use- 
ful effect  will  take  place  when  the 
velocity  is  2  feet  per  second,  or 
about  II  furlongs  an  hour,  con- 
tinued for  10  hours  each  day. 

Smeaton  is  said  to  have  made 
numerous  comparisons,  from  which 
he  concluded  that  the  mechanical 
power  of  a  man  is  equivalent  to 
3750  ibs.  moving  at  the  velocity  of 
one  foot  per  minute;  and  taking 
this  average  to  be  near  the  true 
one,  as  there  is  reason  to  conclude 
it  is,  we  have 


3750 
2x  60 


=  31-25  lbs. 


Therefore,  we  make  the  avemge  me- 
chanical power  of  a  man  31*25  fes. 
moving  at  the  velocity  of  2  feet  per 
second,  when  the  useful  effect  is 
the  greatest  possible ;  or  half  a 
cubic  foot  of  water  raised  two  feet 
per  second ;  a  very  eonTenient  ex- 
pression for  hydrodynamical  in- 
quiries. 

If  a  man  ascend  a  vertical  ladder, 
according  to  a  preceding  remark, 
the  velocity  which  corresponds  to 
the  maximum  of  useful  effect  will 
be  1  foot  per  second,  and  the  load 
double  that  which  he  carries  hori- 
zontally ;  consequently-  the  averse 
of  useful  effect  is  62*5  tba.  raised 
one  foot  per  second. 

Bricklayers'  labourers  in  London  \ 
ascend  ladders  vrith  a  load  of  about 
80  lbs.  besides  the  hod ;  sometimes 
at  the  rate  of  one  foot  per  second, 
but  more  frequently  about  9  inches 
per  second. 

Ascending  stairs  is  more  trying 
to  the  muscles  of  the  legs  tiian 
ascending  a  ladder ;  and  therefore 
the  useful  effect  is  less,  till  a  per- 
son has  become  accustomed  to  this 
kind  of  labour:  and  it  is  also  to 
be  observed  that  the  space  moved 
over  is  increased,  unnecessarily, 
except  where  the  horizontal  dis- 
tance is  part  of  the  path  over  which 
the  load  is  to  be  moved. 

The  force  of  a  horse  is,  at  an 
average,  about  equal  to  that  of  six 
men,  according  to  various  esti- 
mates ;  and  the  rate  of  travdling 
about  the  same,  perhaps  rather 
less  than  that  of  a  man,  when  his 
exertion  is  continued  for  8  houn  .- 
consequently  the  velocity  oone- 
spondhig  to  the  maximum  effect 
will  be  about  2^  feet  per  second. 
Whence,  the  average  mechanical 
power  of  a  horse  may  he  estimated  , 
at  187iibs.  moving  vrith  a  velocity 
of  2i  feet  per  second,  or  3  cubic 
feet  of  water  raised  2^  feet  per  se- 
cond ;  the  day's  work  being  8  hours. 


498 


VEL 


VENTILATION. 


VEN 


Velocity  of  motion.  The  following  is 
a  list  of  the  velocities  of  moving 
bodies,  extracted  from  Peschel's 
*  Elements  of  Physics/  &c. 

FMtperMcond. 


3-4 

13 

10 

54 

80-120 

1100 

12,000 

1280 


Rivers 

A  very  rapid  stream  . 
Wind  (ordinary)  * 
Storm  •  •  • 
Hurricane  .  « 
Sound  ^through  air)  . 

„      (through  metal) 
Air  into  a  vacunm     . 
Ball  from  air-gun  (air  con-  "I      gg^ 

densed  100  times)  .  J 

Musket-ball  .  .  .  1280 
Rifle-bail  (at  most)  .  .  1600 
Cannon-ball  (24-pounder)  .  2450 
Earth's  rotation  (at  equator)  1525 
centre  (in  its  orbit)  101,061 
Miles  per  hour. 


»» 


Race^horse 
Pigeon 

Peregrine  falcon 
Ocean  steamers 
River  steamers  . 
Railway  train  . 
Sailing  vessel  . 
Malay  proa 

Light 
Electricity 


60 
.  20-30 
120 
12 
22 
80 
10 
20 

Miles  per  second. 
.  200,000 
.  576,000 


Velvet  painting  is  the  art  of  colouring 
on  velvet  with  transparent  liquid 
and  other  ready  diluted  colours, 
compounded  and  made  up  with 
various  acids,  alkalies,  &c.,  accord- 
ing to  their  nature  and  qualities 

Venetian  Red  or  Scarlet  Ochre,  True 
Venetian  red  is  said  to  be  a  native 
ochre,  but  the  colours  sold  under  | 
this  name  are  prepared  artificially 
from  sulphate  of  iron,  or  its  resi- 
duum in  the  mcuiufacturing  of  acids. 
They  are  all  of  redder  and  deeper 
hues  than  light  red,  are  very  per- 
manent, and  have  all  the  proper- 
ties of  good  ochres.  Prussian  red, 
English  red,  and  rouge  de  Mars, 
are  other  names  for  the  same  pig- 
ment. 

Ventilation  and  warming  of  buildings 
is  a  twofold  purpose  that  should 

499 


enter  into  the  constructive  design 
of  all  edifices  intended  for  the  resi- 
dence  or  occasional  congregation 
of  human  beings.     The  necessity 
for  this  purpose   arises  from  the 
fact  that  the  breathing  of  air  (as 
one  of  the  functions  of  animal  life) 
renders  it  unfit  for  re-inspiration, 
the  lungs  retaining  the  vital  pro- 
perties and  emitting  the  remainder, 
which  consists  of  ingredients  detri- 
mental to  health,  and  even   de- 
structive of  life  itself.    In  order 
to  keep  an  apartment  in  a  healthy 
and  pleasant  condition,  fresh   air 
should  be  constantly  supplied  at  a 
temperature  from  60°  to  65°,  and 
the  vitiated  air  should  be  as  con- 
stantly removed ;  and  all  the  varied 
schemes  which  have    been    pro- 
pounded for  ventilating  buildings 
have  this  common  purpose  of  con- 
stant supply  and  removal.     The 
vitiated  air,  on  being  emitted  from 
the  mouth,  has  a  temperature  be- 
tween 80°  and  90° ;  and  as  the  uni- 
versal effect  of  heat,  manifested  in 
the  increase  of  temperature  of  the 
supply,  60°  or  65°  to  80°  or  90°, 
is  to  expand  and  lighten,  the  viti- 
ated air  has  a  natural  tendency  to 
rise  to  the  upper  part  of  the  room. 
To  allow  this  action  to  proceed,  it 
is  evidently  necessary  that  means 
for  its  escape  at  the  top  should  be 
provided,  and  also  that  fresh  air 
should  be  introduced  at  the  lower 
portion  of  the   apartment.     The 
operation  would,  however,  be  nulli- 
fied if  the  heated  air,  on  emerging 
from  the  top  of  the  room  into  a 
shaft  or  chimney  intended  to  con- 
duct it  away,  were  met  by  a  down- 
ward current  of  cold  air ;  and  it  has 
therefore  been  deemed  advisable  to 
provide  not  only  such  a  shaft  or 
chimney,  but  also  some  means,  by  1 
stoves  or  other  apparatus,  of  arti-  '. 
ficially  heating  the  air  in  the  shaft,  ; 
and  thus  assisting  the  escape  of 
the  foul  air.   And  further,  in  order 
to  secure  the  constant  accession  of 
fresh  air  and  give  sufficient  impulse 
to  it  to  overcome  any  tendency 


VEN 


VENTILATION. 


VEN 


tliat  might  be  created  to  oppose 
its  introduction  by  a  retro^^nde 
movement  of  the  atmosphere  of 
the  building,  means  have  been 
adopted  of  forcing  this  fresh  air  in 
with  fans  or  bellows.  But  these 
two  sets  of  apparatus  have  been 
seldom  combined.  Those  who  have 
adopted  the  shaft  have  usually  con- 
temned the  fan,  trusting  to  the 
sucking  action  of  the  former  to 
draw  off  all  the  vitiated  air,  and 
concluding  that  fresh  air  must  enter 
as  rapidly  to  fill  its  place;  and, 
on  the  other  hand,  the  adopters  of 
the  fan  decry  the  addition  of  the 
heating  apparatus  in  the  shaft,  and 
contend  that  its  only  effect  is  to 
draw  down  foul  air  for  its  own 
supply,  and  to  impede  the  upward 
current  created  by  this  fan.  This 
effect  should  be  obviated  in  a  well- 
acting  apparatus,  which  would  then 
doubtless  assist  the  fan  in  pro- 
moting the  continual  passage  of 
pure  air  throughout  the  building. 
The  objection  which  has  been  en- 
tertained against  the  use  of  the 
shaft  without  the  fan,  or  some 
other  adequate  forcing  apparatus, 
is  well-founded  on  the  well-known 
elasticity  of  the  atmosphere,  by 
which  it  is  susceptible  of  rarefac- 
tion to  a  considerable  extent.  The 
heated  shaft  consequently  acts  as  a 
pump  in  sucking  the  warmed  air 
upwards,  and  if  no  force  is  in  ac- 
tion from  below  to  drive  this  air 
upward  by  the  pressure  of  fresh 
air  entering  the  apartments,  the 
atmosphere  becomes  rarefied  to  a 
degree  which  is  both  unpleasant 
and  prejudicial  to  sentient  exist- 
ence. It  is  therefore  essential  that 
the  two  processes  of  exhaustion 
and  supply  shall  proceed  simul- 
taneously, and  be  so  regulated  that 
no  rarefaction  shall  be  suffered  in 
the  air  to  be  breathed.  The  pur- 
pose  of  warming  the  air  in  winter, 
and  of  cooling  it  in  summer,  that 
is,  more  properly,  of  attemperating 
it,  should  be  sought,  and  may  be 
attained  conjointly  with  that  of 

500  " 


ventilation;  and  one  of  the  best 
arrangements  yet  carried  out  for 
these  combined  objects  is  pre- 
sented in  the  system  adopted  at 
the  Reform  Club  House  in  London. 
The  supplying  apparatus  there  em- 
ployed consists  of  a  large  fan  which 
revolves  rapidly  in  a  cylindrical 
case,  and  is  adapted  to  throw  11,000 
cubic  feet  of  air  per  minute  into  a 
spacious  subterranean  tunnel  under 
the  basement  story  of  the  huilding. 
This  hn  is  driven  by  a  steam 
engine  of  d-horse  power,  working 
expansively.  It  is  placed  in  a  vault 
in  front  of  the  building,  and  as  it 
bums  anthracite  coal  and  cinders 
from  the  house  fires,  is  not  pro- 
ductive of  any  nuisance  or  offensive 
smoke.  The  steam  of  condensa- 
tion supplies  three  chests,  con- 
structed of  cast  iron,  vrith  the  heat 
requisite  for  wanning  the  building. 
Each  of  these  chests  is  a  cube  in 
form,  and  measures  3  feet  ex- 
ternally, and  is  internally  divided 
into  seven  parallel  cases,  each  3 
inches  wide,  and  separated  by  al- 
ternate parallel  spaces  of  similar 
width,  for  the  passage  of  the  air  as 
it  is  impelled  by  the  fan.  By  this 
economical  arrangement,  which 
thus  makes  good  use  of  the  steam 
of  condensation,  2  cwt.  of  fuel  is 
suflident  for  working  the  engine 
during  twelve  hours,  the  engine 
being  besides  available  for  pumping 
water  for  the  purposes  of  the 
establishment,  and  raising  coals  to 
the  several  apartments  on  the  upper 
stories.  The  air  in  passing  through 
the  cells  between  the  steam  cases 
is  heated  to  a  genial  temperature 
of  from  75"^  to  85%  and  thence 
enters  a  chamber  of  brick-work  in 
the  basement,  from  which  it  is  ad- 
mitted into  several  distinct  flues, 
regulated  by  dialled  valves  or  re- 
gisters, and  thus  conducted  in  any 
required  quantities  to  the  sevenl 
apartments  of  the  building.  A 
stove  is  placed  in  the  top  story, 
and  is  formed  as  a  rectangular 
chest  of  cast  iron,  contracted  above 


YEN 


VIADUCT. 


VIA 


into  a  round  pipe,  which  discharges 
the  burnt  air  and  smoke  into  a 
series  of  horizontal  cast-iron  pipes, 
about  4  inches  in  diameter,  which 
traverse  the  room  beneath  the 
ceiling  and  terminate  in  a  brick 
chimney.  One  advantage  of  such 
an  apparatus  as  is  here  described 
would  be  that  of  introducing  cool 
air  during  sultry  weather,  for 
which  purpose  it  might  be  readily 
adapted. 

Ventilator^  a  machine  made  to  turn 
with  the  wind,  and  placed  in  a 
wall  or  roof,  in  order  to  throw  a 
due  quantity  of  fresh  air  into  a 
close  apartment 

Verdoy,  a  term  in  heraldry,  applied 
when  a  border  is  charged  with 
leaves,  fruits,  and  flowers,  and  like 
vegetables 

Verge,  a  rod,  wand,  or  sergeant's 
mace ;  also  the  compass  about  the 
king's  court  that  bounds  the  ju- 
risdiction  of  the  lord  steward  of 
the  king's  household,  and  of  the 
coroner  of  the  king's  house,  and  is 
accounted  12  mUes'  compass ;  also 
a  rod  whereby  one  is  admitted 
tenant,  holding  it  in  his  hand  and 
swearing  fealty  to  the  lord  of  the 
manor,  and  for  that  cause  called 
tenant  by  the  verge 

Verge,  a  small  ornamental  shaft  in 
Gothic  architecture 

Vermiculatedf  chequered;  continuous ; 
embroidered  with  several  colours 

Vermile,  a  cloth  or  napkin  on  which 
the  fiiice  of  Christ  is  depicted,  de- 
rived from  the  incident  related  of 
of  St.  Veronica 

VermilUon,  a  sulphuret  of  mercury, 
which,  previous  to  its  being  le- 
vigated, is  called  cinnabar.  It  is 
an  ancient  pigment,  and  is  found 
in  a  native  state,  and  produced 
artificially.  VenniUion  probably 
obtained  its  name  from  resem- 
blance to  or  admixture  with  the 
beautiful  though  fugitive  colours 
obtained  from  the  vermes  or  in- 
sects which  yield  carmine 

Vernier,  a  graduated  moveable  index, 
used  for  measuring  minutely  the 

501^  ~^  y5 


parts  of  the  space  between  the 
equidistant  divisions  of  a  graduated 
scale 

Versed  sine  of  an  arc,  in  geometry, 
the  position  of  the  diameter  in- 
tercepted between  the  sine  and  the 
commencement  of  the  arc 

Vert,  in  heraldry,  a  green  colour; 
in  the  ancient  forest  laws,  every 
thing  that  grows  and  bears  a  green 
leaf  within  the  forest  that  may 
cover  and  hide  a  deer 

Vestiary,  a  wardrobe,  or  place  to  lay 
clothes  or  apparel  in 

Vestibule,  in  architecture,  the  porch 
or  the  first  entrance  of  a  hoiisc 

Vestibt^m,  part  of  the  andronitis  of 
a  Greek  house,  similar,  probably, 
to  the  prostas  of  the  first  peristyle 
or  court 

Vestment,  a  set  of  hangings  for  the 
service  of  an  altar ;  and  also  a  suit 
of  robes  for  a  priest 

Via  (Latin),  by  way  of;  m  the  time 
of  the  Romans,  a  road  or  a  right 
of  road.  Two  shallow  trenches 
were  commonly  dug  parallel  to 
each  other,  marking  the  breadth 
of  the  proposed  road :  this  in  the 
great  lines,  such  as  the  via  Appia, 
the  via  Flaminia,  the  via  Valeria, 
&c.,  is  found  to  have  been  from  13 
to  15  feet,  on  the  via  Tusculana  11 ; 
while  those  of  less  importance, 
from  not  being  great  thorough- 
fares, such  as  the  via  which  leads 
up  to  the  temple  of  Jupiter  La- 
tialis,  on  the  summit  of  the  Alban 
Mount,  and  which  is  to  the  pre- 
sent time  singularly  perfect,  seems 
to  have  been  8  feet  wide. 

Viaduct,  a  term  applied  to  extended 
constructions  of  arches  or  other 
artificial  works  to  support  a  road- 
way, and  thus  distinguished  from 
aqueducts,  which  are  similar  con- 
structions to  support  water-ways. 
This  term  has  become  much  more 
familiar  within  the  present  cen- 
tury, in  consequence  of  the  great 
number  of  vast  structures  so  de- 
signated which  have  been  erected 
in  various  parts  of  Great  Britdin 
for  the  purpose  of  carrying  rail- 


••Mas^dikaama^Akirta 


VIA 


VIADUCT. 


VIA 


ways  over  valleys  and  districts  of 
low  level:  but  the  general  name 
of  viaduct  is  now  recognized  as 
applicable  to  all  elevated  roadways 
for  which  artificial  constructions  of 
timber,  iron,  bricks,  or  stone-work 
are  established;  and  accordingly 
among  the  principal  railway-works 
are  to  be  enumerated  viaducts  of 
all  these  materials.  The  vast  di- 
mensions of  some  of  these  struc- 
tures are  not  more  striking  to  the 
casual  observer,  than  their  great 
strength,  as  particularly  adapted  to 
railway  traffic,  is  apparent  upon  a 
careful  study  of  their  construction. 
The  several  members  of  a  viaduct 
are  the  same  as  those  of  a  bridge ; 
indeed,  the  former  structure  may 
be  considered  as  an  extendedbridge, 
frequently  resorted  to  in  situations 
where  no  water  is  to  be  crossed. 
The  necessity  which  is  imperative 
in  the  construction  of  railways  for 
preserving  a  horizontal  level  for  the 
roadway,  or  at  least  departing  from 
this  level  within  very  restricted 
limits,  imposes  the  raising  of  the 
railway  surface  in  many  places,  and 
to  a  considerable  extent  above  the 
natural  level.  Various  considera- 
tions arise  as  to  the  preferable 
mode  of  effecting  this  raising, 
whether  by  solid  embankments  of 
earth-work  or  by  an  open  or  arched 
structure  of  other  materials.  Em- 
bankments of  earth*work  are  often 
liable  to  subsidence  from  want  of 
cohesion  in  the  materials,  or  the 
effect  of  long-continued  rains ;  and 
if  free  from  actual  danger  arising 
from  these  liabilities,  they  are  al- 
ways sources  of  much  constant  ex- 
pense in  making  up  the  surface  to 
the  required  level,  to  compensate 
for  the  continual  depression  caused 
by  the  passage  of  heavy  loads  over 
them.  As  a  question  of  economy, 
therefore,  viaducts  are  often  to  be 
preferred,  since  their  repairs  in- 
volve less  expense  than  those  of 
embankments.  It  must  also  be 
considered  that  the  latter,  owing  to 
their  necessary  extension  of  base, 

502 


cover  a  much  wider  portion  of 
ground  than  viaducts,  and  at  the 
same  time  eover  it  in  a  more  ab- 
solute and  objectionable  manner. 
A  solid  embankment,  like  a  black 
line  across  a  picture^  spoils  a  beau- 
tiful landscape,  and  often  iwecludes 
all  view  beyond  it  from  sites  which 
otherwise  would  command  an  ex- ' 
tended  range.  If  the  sub-forma- 
tion of  the  valley  be  of  a  very  loose 
and  boggy  nature,  embankmenU 
are  scarcely  admissible,  nor,  if  the 
height  to  be  raised  exceeds  30  or 
40  feet,  can  they  be  entertained. 
Indeed,  in  the  majority  of  eases, 
valleys,  whether  having  riven  of 
magnitude  or  not,  are  more  eco- 
nomically crossed  upon  viaducts 
than  embankments. 

Whatever  the  materials  of  the 
structure  or  its  finished  design,  the 
same  points  are  to  be  observed  io 
the  construction ;  and  the  first  of 
these  is  the  strength  and  durability 
of  the  foundations.    A  substantial  > 
and  permanent  character  should 
always  be  secured  for  these,  even 
if  the  superstructure  is  intended  to 
aim  at  cheapness  rather  than  so- 
lidity. It  is  often  requisite  that  the 
piers  and  abutments  be  constracted 
upon  piling, — a  form  of  foundation ' 
adapted,  if  thoroughly   executed., 
to  fUfford  the  most  secure  basis;  but 
if  done  carelessly  and  insufficiently, 
liable  to  involve  the  most  destruc- 
tive faUures.    The  citation  of  a 
few  of  the  most  extended  works  of 
this  class,  of  modem  date,  willi 
best  show  the  details  of  the  present  / 
approved  kinds  of  construction. 

Of  timber  viaducts,  two  fine  ex- 
amples of  sinular  construction  are . 
presented  on  the  line  of  the  New- ; 
castle.  North  Shields,  and  Tyne-| 
mouth  Railway,  and  erected  accord- , 
ing  to  designs  by  Messrs  J.  and  B.  I 
Green,  of  Newcastle.  One  of  these  1 
works,  which   crosses    the  Ousel 
bourn,  besides  a  public  roadway,  a 
mill-race,  and  the  adjacent  valley, 
consists  of  five  spans  or  arches  of 
timber-work,  and  four  end  arches 


VIA 


VIADUCT. 


VIA 


of  masonry.  Of  the  former  arches, 
three  are  116  feet  wide  in  the 
clear,  and  two  114  feet.  Two  of 
the  end  arches  are  43  feet  span, 
and  the  other  two  36  feet.  The 
height  of  the  rails  above  the  bed 
of  the  bourn  is  108  feet.  The 
width  of  the  stmcture  allows  26 
feet  for  a  double  line  of  rails,  and 
5  feet  for  a  footway.  The  total 
length  of  the  viaduct  is  918  feet, 
and  the  two  middle  piers  are 
erected  upon  piles,  from  21  to 
27  feet  in  length.  All  the  piers 
are  of  masonry,  and  tapered  up- 
wards, the  principal  being  21  feet 
wide  above  the  footings,  and  15 
feet  at  the  springing  of  the  arches. 
The  piers  are  continued  upwards, 
of  reduced  dimensions,  to  the  level 
of  the  roadway,  the  whole  of  the 
five  main  arches,  spandrilling,  and 
superstructure,  being  formed  of 
timber.  The  radius  of  these  arches 
is  68  feet,  and  their  rise  or  versed 
sine  about  33  feet.  The  ribs  form- 
ing the  arches  are  composed  of 
planks  of  Kyanized  Dantzic  deal, 
the  lengths  of  which  vary  from 
20  to  46  feet,  by  11  inches  wide, 
and  3  inches  thick.  These  planks 
are  so  arranged,  that  the  first 
course  of  the  rib  is  two  whole 
deals  in  width,  the  next  is  one 
whole  and  two  half- deals,  the 
joints  being  crossed  longitudinally, 
as  well  as  in  the  depth.  The 
thickness  of  each  rib  is  made  up 
of  fourteen  deals,  which  are  bent 
over  a  centre  to  the  required  form,* 
and  fixed  together  with  oak  tre- 
nails, 1^  inch  in  diameter,  placed  4 
feet  apart,  and  each  trenail  per- 
forating three  of  the  deals.  Be- 
tween the  joints  a  layer  of  strong 
brown  paper  is  placed,  previously 
dipped  in  boiling  tar.  The  span- 
diils  are  formed  of  trussed  fram- 
ing ;  and  the  platform  of  the  road- 
way, which  is  composed  of  S^^inch 
planking,  is  supported  upon  trans- 
verse beams  laid  4  feet  apart.  The 
platform  is  covered  with  a  com- 
position of  boiling  tar  and  lime, 

503 


mixed  with  gravel  in  applying  it, 
thus  forming  a  coating  impervious 
to  water. 

There  are  several  other  modes 
of  constructing  timber  Viaducts, 
without  introducing  the  arches, 
composed  of  planks  curved  into 
proper  form,  and  which,  being  laid 
together  like  leaves,  as  just  de- 
scribed, have  obtained  fdr  this 
kind  of  construction  the  name  of  the 
'  laminated  bridge.'  In  other  forms 
I  of  timber  viaducts,  the  requisite 
strength  is  obtained  by  trussing, 
the  peculiar  description  and  com- 
plication of  which  depends,  of 
course,  mainly  on  the  extent  of 
the  span  or  width  of  each  lay  of 
which  the  entire  structure  consists. 
Where  a  great  width  of  clear  open- 
ing is  required,  a  system  of  diagonal 
bracing  offers  peculiar  advantages, 
being  susceptible  of  any  desired 
strength  and  rigidity.  A  viaduct 
of  great  extent,  built  upon  this 
principle,  is  on  the  line  of  the 
Richmond  and  Petersbnrgh  Rail- 
way, North  America.  The  length 
of  this  structure  is  2900  feet,  and 
the  trusses  are  supported  upon 
eighteen  granite  piers,  the  dis- 
tances between  which  vary  from 
130  to  153  feet.  They  are  founded 
on  the  granite  rode,  and  are  40  feet 
high  above  the  water.  The  depth 
of  the  truss-frames  (which  are  ho- 
rizontal on  top  and  bottom)  is  20 
feet.  Another  work  of  the  same 
kind  crosses  the  Susquebannab, 
and  is  2200  feet  in  length,  divided 
into  spans  of  220  feet  each. 

Of  viaducts  formed  of  brick-wprk 
and    masonry,   that    named   the 
*  Avon  Viaduct,'  on  the  Kne  of  the 
North -Western  Railway,  may  be 
mentioned.    This  consists  of  nine 
semi-elliptical  arches,  24   feet  in 
span,  and  7  feet  6  inches  rise,  and 
three  semicircular  arches  at  each 
end  of  10  feet  span.    This  viaduct 
iB  entirely  faced  with  stone,  th« 
interior  of  the  work  being  of  brick 
The  end  arches  have  brick  inverti 
between  the  piers  above  the  found 


VIB 


VILLAS  OP  THE  ANCIENTS. 


VIL 


stioiis,  which  are  laid  uniformly 
in  a  solid  bed  beneath  these  arches, 
with  steps  according  to  the  nature 
of  the  substratum.  An  invert  of 
brick-work  is  built  to  the  three 
middle  arches,  forming  an  artificial 
channel  for  the  river,  and  faced  at 
each  end  with  a  row  of  sheet- 
piling,  driven  through  the  loam 
into  a  bed  of  strong  gravel  beneath. 
AU  the  foundations  which  do  not 
reach  the  gravel  are  laid  upon 
beds  of  concrete,  and  a  layer  of  the 
same  material  covers  the  extrados 
of  the  arches,  and  forms  a  level 
bed  for  the  gravel  in  which  the 
sleepers  of  the  railway  are  bedded. 
Many  similar  works  of  much  more 
extended  dimensions  have  been 
erected  for  railway  communication. 
One  of  these,  of  peculiarly  light 
appearance,  is  known  as  the  *  Vic- 
toria Bridge,'  and  built  over  the 
valley  of  the  river  Wear,  on  the 
line  of  the  Durham  Junction  Rail- 
way. This  work  consists  of  twQ 
main  arches,  one  160  feet  span, 
the  other  144  feet,  two  others, 
each  100  feet  span,  and  six  end 
arches  of  20  feet  span.  The  height 
of  the  parapet  above  the  high- 
water  level  at  spring-tides  is  125 
feet,  and  all  the  arches  are  semi- 
circular. The  central  pier  is  23 
feet  9  inches  in  width,  and  69  feet 
high  from  bottom  of  footings  to 
springing  of  arches.  The  two  con- 
tiguous piers  are  21  feet  wide,  one 
50  feet,  the  other  52  feet  high. 
The  height  of  the  parapet  above 
the  springing  Hue  of  the  two  main 
arches  is  78  feet.  A  viaduct,  re- 
cently constructed  over  the  Moine, 
at  CUsson,  near  Nantes,  in  Brit- 
tany, is  worth  notice,  for  a  pe- 
culiarity in  its  construction,  which, 
although  not  strictly  new,  is  to  be 
found  in  very  few  examples.  This 
peculiarity  is,  that  the  piers  are 
pierced  with  a  pointed  arch,  which 
intersects  the  cylindrical  soffit  of 
the  main  arches  in  the  direction  of 
the  length  of  the  viaduct,  so  that 
the  roadway  is  supported  upon  a 

504 


groined  vault,  which,  seen  firom 
the  abutments,  has  the  ^ipearance 
of  the  aisle  of  a  Gothic  cathednl. 
This  viaduct  consLsta  al  fifteen 
arches,  and  is  348  feet  in  length. 
The  abutments  rest  upon  a  granite 
foundation,  the  atructure  itself 
being  constructed  of  a  fine  iFrhhe 
granite,  and  the  atones  of  iai^ 
size.  The  foundations  are  6  feet , 
below  the  bed  of  the  river,  the 
height  from  which  to  the  spring- 
ing line  of  the  arches  being  ^ 
feet,  and  the  total  height  firom 
the  foundation  to  the  top  of  the ' 
parapet  61  feet 

Vibration,  the  regular  redprocatlBg 
motion  of  a  body,  aa  a  pendulum, ' 
musical  chord,  &c. 

Vice,  a  tool  for  holding  a  peoe  of ; 
metal,  while  operating  upon  it,  by 
placing  it  between  two  jaws  or  nip- 
pers, and  screwing  them  towards  i 
each  other  | 

Vice-bench,  the  bench  to  which  a 
vice  is  fixed 

Villa,  among  the  Romans,  a  turn  or 
country  house 

Villa  rtutica,  a  tasteful  country  r^ 
sidence.  (See  Parker's  '  Villa  Ri»- 1 
tica').  I 

Villa  urbana,  a  residence  ao  called  by 
the  Romans,  because  its  interioi' 
arrangements  corresponded  prin- 
cipally with  those  of  a  towD-boo« 

Villas  of  the  ancients.     Varro  Colu- 
mella says,  "An  estate  should  be  in 
a  wholesome  climate  and  frnit^ 
country ;  one  part  champaign,  and 
the  other  hilly,  with  easy  descents 
either  to  the  east  or  south ;  some  (^ 
the  hmds  cultivated,  others  wild  and ; 
woody }  not  far  from  the  sea  w  • 
navigable  river,  for  the  easier  ex- 
portation of  the  produce  of  the 
farm,  and  the  importation  of  oe- 
cessaries.     The  champaign  Ij^^, 
below  the  house  should  be  di^ ; 
posed  into  grounds  for  pasture  and , 
tillage,  osiers  and  reeds;  aome  of  I 
the  hUls  should  be  naked  and; 
without  trees,  that  they  may  lerye  > 
best  only  for  com,  which  gro^  ^ 
a   soil  moderately  dry  and  richt 


VIL 


VILLAS  OF  THE  ANCIENTS. 


VIL 


better  than  in  steep  grounds ;  where- 
fore the  upper  corn-fields  should 
have  as  little  declivity  as  possible, 
and  ought  to  resemble  those  in  the 
plain :  from  thence,  the  other  hiUs 
shouldbe  laid  outinto  olive-grounds 
and  vineyards,  and  produce  trees 
necessary  to  make  props  for  those 
fruits,  and,  if  occasion  should  re- 
quire building,  to  a£ford  timber 
and  stone,  and  also  pasture  for 
cattle.  Moreover,  constant  rivu- 
lets of  water  should  descend  from 
thence  upon  the  meadows,  gardens, 
and  osier-grounds,  and  also  serve 
for  the  convenience  of  the  cattle 
that  graze  in  the  fields  and  thickets : 
but  such  a  situation  is  not  easily  to 
be  met  vnth;  that  which  enjoys 
most  of  these  advantages  is  cer- 
tainly most  valuable ;  that  which 
has  them  in  a  moderate  degree,  is 
not  despicable.  The  natural  good 
qualities  of  a  situation  mentioned 
by  PaUadio  are,  a  salutary  au:, 
plenty  of  wholesome  water,  a 
fruitful  soil,  and  a  commodious 
place :  we  may  hence  conclude  that 
those  places  are  healthy  that  are 
not  located  in  deep  yalleys,  or 
subject  to  thick  clouds,  where  the 
inhabitants  are  of  a  fresh  com- 
pleidon,  have  clear  heads,  good 
sight,  quick  hearing,  and  a  firee  dis- 
tinct speech ;  for  by  these  things  is 
the  goodness  of  the  air  distinguish- 
ed; and  the  contrary  appearance 
proclaimsthat  dimateto  be  noxious. 
The  unwholesomeness  of  water 
may  be  thus  discovered:  in  the 
first  place,  it  must  not  be  conveyed 
from  the  ditches  or  fens,  or  rise 
from  minerals,  but  be  very  trans- 
parent, not  tainted  either  in  taste 
or  smell,  vnthout  settlement,  in 
winter  warm,  in  summer  cold ;  but 
because  nature  often  conceals  a 
more  lurking  mischief,  in  these 
outward  appearances,  we  may 
judge  whether  water  is  good  by 
the  health  of  the  inhabitants :  if 
their  cheeks  are  dear,  their  heads 
sound,  and  little  or  no  decay  in 
their  lungs  and  breasts ;  for  gene- 

505 


rally  where  the  distempers  in  the 
upper  part  of  the  body  are  trans- 
mitted down  to  the  lower,  as  from 
the  head  to  the  lungs  or  stomach, 
there  the  air  is  infectious :  besides, 
if  the  belly,  bowels,  sides,  or  vejns, 
are  not  afflicted  mth  aches  or  tu- 
mours, and  there  is  no  ulcer  in  the 
bladder;  if  these  or  the  like  are 
apparently  in  the  major  part  of  the 
inhabitants,  there  is  no  cause  to 
suspect  the  unwholesomeness  of 
the  air  and  water.  The  £atal  con- 
sequences proceeding  from  bad  air, 
Varro  tells  us,  are  in  some  measure 
to  be  alleviated,  if  not  prevented,  by 
the  skill  of  the  architect.  His 
words  are:  That  land  which  is 
most  wholesome  is  most  profitable, 
because  there  is  a  certain  crop; 
whereas,  on  the  contrary,  in  an  un- 
healthy country,  notwithstanding 
the  ground  is  fertile,  yet  sickness 
will  not  allow  the  husbandman  to 
reap  the  fruits  of  his  labour ;  for 
where  one  exposes  his  life  to  cer- 
tain dangers,  for  uncertain  advan- 
tages, not  only  the  crop,  but  the 
life  of  the  inhabitant,  is  precarious ; 
wherefore,  if  it  is  not  wholesome, 
the  tillage  is  nothing  else  but  the 
hazard  of  the  owner's  life  and  his 
family :  but  this  inconvenience  is 
remedied  by  knowledge,  for  health, 
which  proceeds  from  the  air  and 
soil,  is  not  in  our  disposal,  but 
under  the  guidance  of  nature ;  yet, 
nevertheless,  it  is  much  in  our 
power  to  make  that  burthen  easy 
by  our  own  care;  for,  if  upon 
account  of  the  land  or  water,  or 
some  unsayoury  smell,  which  makes 
an  irruption  in  some  part  of  it,  the 
farm  is  made  unwholesome,or  upon 
account  of  the  climate,  or  a  bad 
wind  that  blows,  the  ground  is 
heated,  the^e  inconveniences  may 
be  remedied  by  the  skill  and  ex- 
pense of  the  owner,  which  makes 
it  of  the  last  concernment  where 
the  villas  are  placed,  bow  large 
they  are,  and  to  what  quarters  their 
porticoes,  gates,  and  windovrs  are 
turned.    Did  not  Hippocrates  the 


VIL 


VILLAS,  ROMAN. 


VIL 


- 


phyddui,  in  the  time  of  a  great 
plag;ue,  preserve  not  only  his  own 
fiurm,  but  many  towns,  by  his  skilL' 
When  Varro  and  his  army  and 
his  fleet  lay  at  Corcyra,  and  every 
house  was  filled  with  siek  persons 
and  dead  bodies,  by  his  care  in 
making  new  windows  to  the  north- 
east, and  obstructing  the  infection 
by  altering  thepositionof  the  doors, 
he  preserved  his  companions  and 
fiumly  in  good  health.  As  a  house 
should  be  built  in  a  wholesome 
country,  so  it  should  be  in  the  most 
wholesome  part  of  a  country ;  for, 
an  open  air,  and  at  the  same  time 
infected,  causes  many  distempers." 
Villas  (Roman).  The  term  viUa  was 
applied  to  a  cluster  of  buildings  in 
the  country  for  the  accommodation 
of  the  family  of  a  wealthy  Roman 
citizen.  Very  extensive  villas  were 
divided  into  three  parts ;  the  Ur- 
bana,  the  Rustica,  and  the  Fruc- 
tuaiia.  The  first  contained  the 
eating-room,  bed-chambers,  baths, 
covered  porticoes,  walks,  and  ter- 
races.  The  villa  rustica  was  the 
division  for  the  servants,  stables, 
&c. ;  and  the  fructuaria  for  wine, 
oil,  and  the  produce  of  the  farm. 
Although  the  Roman  villas  were 
the  boast  and  delight  of  poets  and 
philosophers  whose  works  have  for- 
tunately reached  us,  yet  no  de- 
scription has  been  conveyed  of  their 
external  architecture.  From  the 
magnificent  style  of  public  build- 
ings at  Rome,  modems  were  led  to 
suppose  that  the  villa  architecture 
bore  some  analogy  in  splendour  of 
outward  appearance ;  but  from  in- 
spection of  their  remains,  and  from 
the  late  disinterment  of  one  on  the 
outside  of  the  walls  of  Pompeii, 
little  doubt  now  remains  on  the 
subject.  It  is  true  that  the  exten- 
sive remains  of  Adrian's  villa,  and 
that  of  Mecienas,  covered  ground 
equal  almost  to  a  small  town,  but 
no  regular  plan  of  architectural 
elevation  can  be  traced  with  all  the 
ingenuity  of  even  a  Roman  anti- 
quary.    The  Pompeian  is  certainly 

506 


the  most  complete  example  of  an 
ordinary  sized  Roman  villa:  situ- 
ated on  a  sloping  bank,  the  front 
entrance  opened,  as  it  were,  into 
the  first  floor,  below  which,  on  the 
garden  side,  into  which  the  house 
looks,  (for  the  door  is  the  only 
aperture  on  the  road  aide,)  was  a . 
ground  floor,  with  extensive  ar- 
cades  and  open  rooms,  all  fridDg 
the  garden;  and  above  were  the 
principal  rooms.  It  was  spacious, 
and  near  the  entrance  was  a  bath 
with  all  the  necessary  appendages ; 
in  the  rear  the  best  rooms  opened 
upon  a  terrace,  running  the  whole 
width  of  the  house,  and  overlook- 
ing a  garden  about  30  yards  square, 
surrounded  by  a  covered  wjdk  or 
portico  continued  under  the  terrace. 
The  lower  apartments  under  the 
arcade  were  paved  with  mosaic, 
coved  and  beautifully  painted.  One 
of  the  rooms  had  large  glazed  bow- 
windows;  the  glass  was  thick,  of 
a  green  colour,  and  set  in  lead  like 
a  modem  casement.  The  vralls 
and  ceilings  of  the  villa  were  orna- 
mented with  paintings  of  elegant ' 
design,  all  of  which  had  relation 
to  the  uses  of  the  respective  apart- 
ments. In  the  middle  of  the  gar- 
den was  a  reservoir  of  water,  sur- 
rounded by  columns.  The  cellars 
extended  under  the  whole  of  the 
house  and  the  arcades. 

Pliny  tells  us  that  the  size  of 
the  villa  urbana,  and  its  nnmber  of 
parts,   were    determined    by   the 
pleasure  or  quality  of  the  master, 
but  those  parts  belonging  to  agri- 
culture, by  the  bulk  of  the  farm 
and  the  number  of  cattle.  The  ser-  . 
vants   that  in  most  great  men's 
houses  were  more  immediately  for 
the  master's  use,  and  may  be  said  to  ' 
have  belonged  to  the  villa  urbana,  | 
were  the  atrienset,  which  included  ! 
all  those  we  call  livery  servants,  and  ' 
those  belonging  to  the  bed-cham- 1 
her ;  and  the  tqpiarii,  which  were  I 
gardeners  belonging  to  thepleasure-  ' 
garden;  with  comedians, musicians,  I 
and  the  notaries  or  secretaries.  The  I 


VIL 


VILLAS,   ITALIAN. 


VIS 


principal  pcraon  over  the    other 
parts  of  the  villa  was  the  procurator 
or  baiUff ;  then  the  viUicus  or  hus- 
bandman, who  had  under  his  care 
the  tillage  of  the  land,  and  the 
disposal  of  the  produce  of  the  earth 
about  the  villa;  next  was.the  wtftcfl 
or  house-keeper,  to  whose  care 
every  thing  within  doors  belonged, 
and  who  had  immediately  under  her 
command  the  women  servants  that 
were  employed  in  those  affairs,  but 
particularly  those  belonging  to  the 
feeding  and  clothing  of  the  house- 
hold.   The  master  of  the  cattle 
may  take  the  next  place,  and  under 
his  command  were  all  the  herds- 
men, shepherds,  goatherds,  swine- 
herds, and  grooms.    The  care  of 
all  those  fowl  that  were  within  the 
bounds  of  the  villa  was  conmdtted 
to  the  poulterer.    In  great  villas  it 
was  thought    necessary    to  keep 
within  the  family  useful  mechanics, 
as  smiths,  carpenters,  &c.     The 
cattle  within  the  villa  were  horses 
and  mules,  &c. ;  and  to  make  pro- 
vision for  the  several  persons  and 
animals,   and    also  for  corn  and 
the  necessary  offices  of  the  house, 
was  the  architect's  care ;  and  the 
disposition  of  each  part  was  go- 
verned by  rules  that  may  be  col- 
lected from  Cato,  Vitruvius,  Varro 
Columella,  and  Palladius. 

Of  the  Greek  viUas,  no  descrip- 
tion has  been  transndtted  to  us ; 
in  villa  gardening,  however,  con- 
siderable progress  at  that  time  was 
made,  borrowed  probably  from 
Asia  Minor:  myrtle*  and  roses 
adorned  them ;  the  box  and  lime 
tree  were  planted  for  topary  works; 
and  Theophrastus  teUs  us,  that 
flowers  and  fruits  were  cultivated 
in  the  winter ;  and  the  violet  more 
particularly  was  in  profusion  in  the 
market  of  Athens  while  snow  was 
on  the  ground. 
ViUae  {Italian^  The  description  of 
an  Italian  vUla  built  in  the  time  of 
Michael  Angelo,  Raphael,  Julio 
Romano,  Dominichmo,  Paul  Ve- 
ronese, and  Pietro  da  Cortona,  de- 


serves  the  notice  of  ar  ehitects.  **  The 
palace  of  Caprarola  it  situated  on 
the  siunmit  of  Mount  Camino,  near 
Viterbo:  below  is  the  village  of 
the  same  name,  of  whieh  the  prin- 
cipal  street  runs  in  a  direct  line 
down  the  descent  from  the  front 
of  the  building,  but  with  a  sufllcient 
space  between  them.     A  double 
stair,  partly  dhreet,  partly  curved, 
with  terraced  landing-places  deco- 
n^d  vnth  balustrades,  leads  to  the 
palace.    Entrances  under  the  ter- 
races  of  the  stairs  conduct  to  the 
underground  parts  of  the,  building. 
The  form  of  the  palaee  is  a  pen- 
tagon  flanked  by  five  bastions,  sur- 
rounded by  a  sunk  area.     Hence 
there  is  a  mixture  of  dvil  and 
military  architecture   that  has   a 
good  effect.     The  palace  is  built 
in  two  orders  of  architecture ;  the 
one  Jonic,  with  semicircular-headed 
windows;  the  upper,  Corinthian, 
comprehending  both  the  first  floor 
and  the  mezzanine  above.    Within 
the  pentagonal  figure  is  included  a 
circle,  comprehending  the  court, 
the  porticoes,  the  offices,  and  stairs. 
The  decorations  of  the  whole  and 
the  parts  are  executed  with  much 
skill.    Although  the  entire  edifice 
is  not  great,  yet  the  parts  are  on  a 
great  scale,  apparently." 

Virtuoso,  a  man  skilled  in  antique  or 
natural  curiosities,  studious  of 
painting,  statuary,  or  architecture 

Vis  absohaa,  absolute  force 

Vise,  a  spiral  staurcase,  the  steps  of 
which  wind  round  a  perpendicular 
shaft  or  pillar,  called  the  newel 

Vis  mertuBy  the  propensity  of  nature 
to  remain  in  its  actual  condition, 
whether  of  motion  or  rest,  and  to 
resist  change 

Vis  msita,  the  power  or  innate  force 
essentially  residing  in  any  body,  and 
by  which  it  endeavours  to  preserve 
its  present  state,  whatever  that  be 

Viscount,  in  law,  signifies  as  much  as 
sheriff:  in  heraldry,  it  signifies  a 
degree  of  nobility  next  to  an  earl 

Vis  viva  (work).  The  vis  viva  of 
a  body  is  its  mass  multiplied  by 


VIT 


WAINSCOT. 


WAL 


the  square  of  its  velocity :  work, 
or  dynamical  effect,  supposes  a  body 
moYed,  and  a  resistance  oyeroome; 
and  either  of  these,  without  the 
other,  is  insufficient  to  constitute 
work.  The  work  produced  by  a 
pressure  moving  a  body  through  a 
certain  space  is  defined  to  be  the 
product  arising  from  multiplying 
the  pressure  by  the  space  through 
which  this  pressure  acts. 

VitreouSf  glassy ;  consisting  of  or 
resembling  glass 

Vitr^icatwnj  the  act  of  changing  into 
gkss 

Vitriolf  oil  of,  sulphuric  acid 

VHrtman  ScroUf  a  peculiar  pattern 
of  scroll-work,  consisting  of  con- 
volved undulations,  used  in  clas- 
sical architecture 

Viz,  (To  unt)t  that  is ;  a  contraction 
of  videlicet 

Voider^  in  heraldry,  a  gentlewoman's 
armory,  consisting  of  an  arch  hue, 
moderately  bowing  from  the  comer 
of  the  chief  toward  the  nombril  or 
centre  of  an  escutcheon 

Voiding f  a  term  in  heraldry,  signifying 


exemption  of  some  part  of  the  in- 
ward substance  of  things  voidable, 
by  reason  whereof  the  field  is  trans- 
parent through  the  charge 

Volant,  in  heraldry.    When  a  bird  is 
drawn  flying,  or  having  the  wings , 
spread,  out,  it  is  said  to  be  volant  ' 

Volute,  The  characteristic  ornaments 
and  indidal  marks  of  the  Ionic 
capital  formed  by  drcumvolmg 
spiral  mouldings  are  termed  to- 
lutes.  The  small  circle  in  which 
the  spiral  or  springs  terminate  is 
called  the  eye  of  the  volute.  The 
introduction  of  volutes  is  said  by 
Vitruvius  to  have  arisen  from  in 
imitation  of  the  mode  in  which 
women  were  formerly  accustomed 
to  ornament  their  hair;  bot  they 
are  thought,  with  greater  proba- 
bility, to  have  represented  the 
horns  of  the  Ammonian  Japiter. 

Voussoira^n  architecture,  vault-stones, 
or  those  that  immediately  form  the 
arch  of  a  bridge,  vault,  &c,  and 
are  cut  somewhat  in  the  shape  of 
a  truncated  pyramid  < 

Vuffhf  in  mining,  a  cavity  | 


WAG 

Waggons,  vehicles  for  the  convey- 
ance of  persons,  merchandise,  &c., 
varying  in  form  according  to  their 
use,  and  dating  in  their  origin 
from  the  remotest  antiquity:  **  Jo- 
seph gave  them  waggons,  according 
to  the  commandment  of  Pharaoh, 
and  gave  them  provision  for  the 
way." — Gen.  xlv.  21. 

Waggon^boHeTf  a  low-pressure  boiler, 
having  the  form  of  a  waggon,  with 
arched  top  and  incurvated  sides 

Wainscot,  a  name  given  to  boards  em- 
ployed to  line  the  internal  walls 
of  an  apartment,  so  called  from 
foreign  species  of  oak  named  wains- 
cot being  first  used  for  such  a 
purpose.  Wainscoting,  as  it  is 
called,  both  of  Flemish  and  Eng- 
lish oak,  was  commonly  used  for 
interior  hnings  in  Tudor,  Eliza- 
bethan, and  Stuart  times. 


WAL 

Waitt,  in  a  ship,  the  uppermost  part 
of  the  top-side 

Wake,  in  navigation,  denotes  the 
print  or  track  of  a  ship  on  the 
surface  of  the  waters.  Two  dis- 
tinct objects  seen  at  sea  are  said  to 
be  in  the  wake  of  each  other  when 
the  view  of  the  furthest  is  inter- 
rupted by  the  nearest. 

Wales,  in  ship-buildipg,  are  an  as- 
sembUige  of  strong  planks  extend- 
ing along  a  ship's  side,  serving  to 
reinforce  the  decks  and  fonn  the 
curves  of  the  vessel 

Wallftlate,  a  piece  of  timber  placed 
along  the  top  of  a  wall,  to  reoeire 
the  ends  of  the  roof  timbers,  or  so 
placed  on  a  wall  as  to  receive  the 
joists  of  a  floor 

Walnut  wood.  The  royal  or  com- 
mon walnut  is  a  native  of  Persia 
and  the  north  of  China :   it  was 


WAR 


WATBR. 


WAT 


formerly  much  used  in  England 
before  the  introduction  of  ma- 
hogany. The  heart  wood  is  of  a 
grayish  brown,  with  black-brown 
pores,  and  often  much  yeined  with 
darker  shades  of  the  same  colour. 
Some  of  the  handsome  veneers  are 
now  used  for  furniture,  frames  of 
machines,  gun-stocks,  &c. 

Wardrobe,  a  place  where  the  gar- 
ments of  kings  or  great  persons 
used  to  be  kept;  and  he  that 
keeps  the  inventory  of  all  things 
belonging  to  the  king's  wardrobe 
is  called  Clerk  of  the  King's 
Wardrobe 

Wards  and  Liveries,  a  certain  court 
erected  in  the  time  of  Henry  YIII. 

Warp,  in  navigation,  to  change  the 
situation  of  a  ship  in  hu-bour, 
&c.,  by  means  of  ropes  or  warps 
attached  to  buoys,  posts,  rings, 
trees,  &c« 

JVaahinff,  in  painting,  to  lay  a  colour, 
such  as  Indian  ink  or  bistre,  over 
a  pencil  or  crayon  drawing,  to 
render  it  more  natural,  and  add  to 
the  shadow  of  prominences,  aper- 
tures, &c. 

Wassail,  a  term  which  is  said  to  have 
had  its  origin  at  the  meeting  of  Vor- 
tigem  and  Rowena,  the  daughter 
of  Hengist.  Geofifrey  of  Monmouth 
states,  that  the  lady  knelt  before 
the  king,  and  presenting  him  with 
a  cup  of  wine  said,  *  Waes-hsel,' 
which  in  Saxon  means  '  Health  be 
to  you/  Vortigem,  as  he  was  in- 
structed, replied,  *  Drinc-hsel,'  t.  e, 
*  drink  the  health :'  Rowena  drank, 
upon  which  Vortigem  took  the  cup 
and  pledged  her.  Hence  the  term 
and  custom. 

Waste  steam-pipe,  in  steam  engines, 
the  pipe  leading  from  the  safety- 
valve  to  the  atmosphere 

Waste  water-pipe,  in  steam  engines, 
the  pipe  for  carrying  off  the  surplus 
water  from  the  hot  well 

Water  is  the  most  abundant  and  im- 
portant  fluid  in  nature :  it  is  proved 
to  be  composed,  by  weight,  of  8 
parts  of  oxygen  and  1  part  of 
hydrogen,  and  is  resolvable  into 

509 


both  these  gases  by  Toltaic  action 
and  by  intensely  ignited  platinum: 
other  heated  metals  combine  with 
its  oxygen,  and  liberate  the  other 
gas.    When  hydrogen  and  oxygen 
are  mixed  in  the  proportion  given, 
and  ignited,  they  unite  with  explo- 
sion, and  water  alone  is  produced. 
The  purest  water  in  nature  is  that 
which  descends  from  the  atmo- 
sphere; that  of  springs,  rivers,  and 
the  ocean  being  more  or  less  charged 
with  mineral  matter.     When  the 
foreign  substance  iu  not  volatile, 
the  water  is  easily  separable   hy 
distillation  in  the  form  of  a  pure 
vapour  or  steam,  while  the  fixed 
substance  remains.    In  nature,  the 
solar  heat  produces  this  effect  on  a 
vast  scale,  evaporating  enormous 
quantities  of  water  into  the  atmo- 
sphere, whence,  by  cooling  to  va- 
rious degrees,  it  falls  again  in  the 
form  of  rain,  hail,  or  snow :  this, 
in  its  passage  through  different 
strata  towards  its  lowest  level,  dis- 
solves any  soluble  matters  which 
it  may  encounter,  of  which  salt  is 
the  most  conspicuous,  conveying 
them  ultimately  into  the  ocean. 
This  process,  operating  for  ages,  is 
fully  sufficient  to  account  for  the 
prevalence  of  so  soluble  a  mineral 
as  common  salt  in  sea-water,  and 
the  comparative  purity  of  that  of 
rivers. 

When  water  runs  through  beds 
of  chalk  or  selenite,  it  acquires  both 
an  acid  and  alkaline  quality  in  a 
smalldegree.  The  acid  is  discovered 
by  a  few  drops  of  solution  of  oil  of 
tartar:  this  alkali  vnll  seize  the 
acid,  and  descend  with  it  in  a  cloud 
to  tl&e  bottom  of  the  glass,  where, 
if  permitted  to  stand  a  sufficient 
period,  it  vnll  concrete  into  a  neu- 
tral salt.  The  alkaline  part  is 
discoverable  by  a  few  drops  of 
the  solution  of  oxalic  acid.  This 
acid  bas  so  strong  an  affinity  to  I 
calcareous  earth,  that  the  smallest 
quantity  in  water  is  detected  by 
it.  There  are  numerous  tests  which 
discover  acid  and  alkali  in  water ; 


WAT 


WATER. 


WAT 


.  as,  the  syrup  of  Tiolets,  tinctare  of 
turnsole,  ash-bark,   log;wood,  &c. 
Strictly,  philosophically  speaJung, 
tea-water  is  not  salt,  because  if  a 
given  quantity  is  put  into  a  glass 
retort,  by  sand  heat  from  material 
fire  it  will  pass  over  perfectly  fresh, 
and  the  marine  salt  it  contained 
will  be  left  behind.     Snow  and 
ndn  waters,  when  collected  at  a 
distance   from   smoky  towns   or 
cities,  if  collected  and  kept  in  a 
stagnated  state,  go  repeatedly  into 
a  state  of  fermentation,  and  some- 
times become  putrid,  by  the  ex- 
traneous matters  Uiey  receive  in 
passing  through  the  lower  atmo- 
sphere, previous  to  their  reaching 
the  earth.    If  the  specific  gravity 
of  water  is   considered  at  1000 
ounces  the  cubic  foot,  common  air 
will  be  If,  fine  gold  will  be  ^j^hn^, 
and  pure  platina  nhni  or  if  a 
datum  is  taken  of  1  ror  water,  gold 
will  be  20,  and  refined  platinum  22. 
Water  is  incompressible,  as  expe- 
riment proves.    It  has  been  put 
into  a  gold  globe,  and  great  power 
applied  in  vain  to  press  it  into 
a  smaller  compass;  it  passed  off 
by  oozing  or  sweating  through  the 
pdres  of  gold.    It  will  rise  in  some 
eases  above  its  own  level,  in  a 
small  degree,  by  capillary  attrac- 
tion.   If  a  piece  of  dry  loaf  sugar 
or  sponge  is  put  into  a  shallow 
vesscd  of  water,  and  have  part  of  it 
uninunerged,  the  fluid  will  be  seen 
to  ascend  above  its  leveL  Water  will 
also  ascend  to  the  height  of  32  or 
33  feet  above  its  level  in  a  vacuum, 
as  in  pumps,  by  the  pressure  of  the 
atmosphere,  which  varies  more  or 
less  according  to  its  density,  that 
is,  calculating  on  the  pressure  of 
the  atmosphere,  at  the  height  of 
15  miles.    The  pressure  of  water 
on  the  base  of  the  vessel  in  which 
it  is  contained  is  as  the  base  and 
perpendicular  altitude,  whatever  be 
the  figure  of  the  vessel  that  con- 
tains it.     A  body  immersed   in 
water  loses  as  much  weight  as  an 
equal  bulk  of  the  water  weighs, 


and  the  water  gains  the  same 
weight.  Thus,  if  the  body  be  of 
equal  density  with  the  vrater,  it 
loses  all  its  weight,  and  so  requires 
no  force  but  the  water  to  sostsin . 
it :  if  it  be  heavier,  its  weight  in 
the  water  will  be  only  the  difier- 
enoe  between  its  own  weight  and 
the  weight  of  the  same  bulk  of 
water,  and  it  requires  a  force  to 
sustain  it  just  equal  to  that  differ- 
ence; but  if  it  be  lighter,  it  re- 
quires a  force  equal  to  the  same 
difference  of  weight  to  keep  it  firom 
rising  up  in  the  fluid. 

Water  of  great  rivers  may  cer- 
tainly be  deemed  the  most  pore 
and  wholesome  for  all  culinan 
and  domestic  concerns,  independ- , 
ent  of  its  superior  fertilizing  powen 
when  used  for  the  purpose  of  agri- 
culture or  the  growth  of  jdants; 
and  when  thrown  into  reservoizs, 
and  deared  of  its  sediment,  it  be- 
comes clear  and  equally  transparent 
with  the  brightest  water  proceeding 
from  the  hardest  rock;  for,  pre- 
vious to  its  being  thus  deposited, 
while  swiftly  gliding  witiiin  its 
banks,  it  deposits  large  portions  of 
its  bituminous,  calcareous,  argil- 
laceous, and  chalybeate  qualities. 

Water  is  a  conductor  of  atmo- 
spheric air,  as  well  as  sound. 
In  Ralph  Dodd's  *  Civil  Engineer 
an  accident  is  mentioned,  by  which 
one  of  his  workmen  was  buried, 
by  the  falling  of  40  feet  of  a  shaft, 
the  bottom  of  which  approached 
to  a  sand  highly  champed  with 
water.  He  remained  from  Friday 
evening  till  Tuesday  morning.  The 
workmen  were  this  oonsiderabie 
time  before  they  came  to  him, 
conversing  together  and  excavating 
over  his  head,  which  conaiderablT 
increased  his  hope  of  being  re- 
leased frt>m  his  horrid  captivity; 
for  he  became  aware  of  their 
endeavours  for  his  release  as  soon 
as  the  workmen  had  entered  the 
sandy  stratum,  through  which  the 
water  filtered  downward, — a  strong 
evidence  of  its  conveying  sound. 


510 


WAT 


WATER-COLOUR  PAINTING. 


WAT 


as  well  as  atmospheric  air,  or, 
doubtless,  he  could  not  have  ex- 
isted. 

Day-springs,  either  lying  near 
the  surface  of  the  earth,  or  finding 
fresh  passages  thither,  break  forth 
into  open  air  on  their  own  account ; 
while  those  of  a  deeper  nature  are 
sunk  down  so  low  as  to  require 
hydraulic  machinery  to  bring  them 
up  again.  Next,  they  are  called 
top-springs,  inasmuch  as  they  ap- 
pear either  above  the  rock  which 
severs  the  soil  from  the  mine,  or 
underneath  it.  Top-springs  differ 
from  deep  or  other  springs,  in  that 
they  stagnate  between  the  super- 
ficies of  the  earth  and  the  surface 
of  the  parts  confining  them,  till 
they  are  opened  by  the  miner; 
and  those  springs  that  can  be  let 
off  by  drifts,  headings,  songhs,  and 
trenches,  are  distinguished  from 
those  of  the  deep,  the  draining 
of  which  by  such  means  is  alto- 
gether impracticable  or  absolutely 
impossible.  In  the  search  after 
the  original  source  of  those  cur- 
rents of  water,  which,  issuing  out 
of  the  earth,  and  are  commonly 
called  day-springs,  the  first  con- 
sideration that  arises  is,  that  their 
natural  course,  as  consisting  in 
motion,  is  merely  local,  and  caused 
by  the  propension  of  their  own 
weight,  still  drawing  them  down- 
vrard,  towards  the  centre  of  the 
earth :  their  course  must  always  be 
upon  a  constant  descent  from  a 
higher  situation  to  a  lower,  and 
so  must  proceed  originally  from 
rain,  distilled  from  the  clouds. 
And  if  it  happen,  that  at  their 
emersion  out  of  the  earth,  their 
spring  rises  upwards,  it  is  caused 
by  the  curvity  of  their  jNissage, 
that  (syphon-like)  points  the  way ; 
while  the  preponderance  of  the 
water  contained  in  its  other  arm, 
descending  from  a  greater  height, 
forces  it  to  rise  contrary  to  its 
natural  inclination. 

The  specific  gravity  of  rain-water 
is  1000;  weight  of  a  cubic  foot 

511 


62i  lbs. ;  weight  of  a  column,  one 
inch  square  and  a  foot  in  height, 
0*434  ibs.;  of  an  ale  gallon  10'2  lbs.: 
expands  fy  of  its  bulk  in  freezing, 
and  'g^  for  every  degree  of  heat : 
boils  at  212^  imder  the  ordinary 
pressure  of  the  atmosphere  2  max- 
imum density  39*''38  of  Fahr.  The 
specific  gravity  of  sea-water  is 
11-0271. 

WateT'Colour  painivng  is  the  art  of 
making  a  picture  with  colours 
ground  up  with  various  kinds  of 
aqueous  gnms  or  sizes,  then  called 
transparent  colours.  These  draw- 
ings are  executed  on  various  kinds 
of  paper,  and  are  generally  termed 
tinted  drawings.  The  following 
are  the  most  permanent  colours, 
and  therefore  most  valuable  to  the 
water-colour  painter :  bluet — ul- 
tramarine, French  ultramarine,  co<* 
bait,  indigo,  and  smalt :  redt — In- 
dian red,  light  red,  Venetian  red, 
scarlet  vermillion,  carmine,  pink 
madder,  rose  madder,  purple  lake, 
and  red  orpiment:  yellows — cad- 
mium yellow,  gamboge,  yellow 
ochre,  Indian  yellow,  man  yellow, 
lemon  yellow,  Roman  ochre,  brown 
ochre,  mars  orange,  raw  sienna, 
Italian  pink,  gallstone,  and  king's 
yellow:  purplet — purple  madder, 
Indian  purple,  and  burnt  carmine : 
brown* — ^bumt  sienna,  brown  pink, 
burnt  umber,  Vandyke  brown,  se- 
pia, mara  brown,  Cologne  earth, 
bistre,  and  madder  brown  s  greent 
— emerald  green,  olive  green,  and 
green  oxide  of  chromium:  blacks 
— ^ivory  black,  blue  black,  neutral 
tint,  and  British  ink :  whites — ox- 
ide of  zinc  or  Chinese  white,  and 
sulphate  of  barytes  or  constant 
white. 

Water-crane^  an  apparatus  for  sup-> 
plying  water  from  an  e\cv«ted  tan^ 
to  the  tender  of  alocomotwc  engviie 

Watering  the  streets  0/  P«»^    C*/*® 
contract  for).    The  contractor  toi 
this  service  receives  105,000  franc* 
per   annum,  or   iS4200   atciJi^S. 
It  lasts  from  March  15th  to  Octo- 
ber 15th. 


WAT 


WATER  SUPPLY. 


WAT 


He  is  bound  to  hold  at  the  dis- 
posal of  the  engineers  who  are 
charged  with  the  direction  of  the 
roads,  twenty-five  carts  during  the 
first  month  of  the  season ;  during 
the  second,  the  number  is  fixed  at 
fifty-five ;  during  the  remainder  at 
ninety,  with  fifteen  others  in  re- 
serve. These  carts  can  only  be 
used  for  the  service  of  the  town ; 
and  they  are  repainted  tvery  year. 
They  contain  1  metre  cube,  or  1 
ton  each,  and  are  drawn  by  -one 
horse.  They  have  a  double  dis- 
charge hose ;  at  the  front  and  at 
the  back.  At  half-play  they  water 
1000  metres  superficiaL  At  full 
play  they  water  700  metres  super- 
ficial. In  the  first  case,  they  are 
emptied  in  10  minutes;  in  the 
second,  in  6  minutes.  Each  cart 
costs  800  francs,  or  JS32;  of  which 
200  francs,  or  £S,  are  for  the  ma- 
chinery necessary  for  the  distribu- 
tion of  the  water. 

The  Avenue  de  Neuilly  in  the 
Champs  Elysees  forms  a  special 
service,  on  account  of  the  immense 
number  of  carriages  which  traverse 
it.  The  total  surface  is  32,000 
metres  superficial,  or  nearly  8  acres 
English  (7-976  a.)  The  cost  per 
day  in  the  summer  months  is  as 
follows : 

2  water  carts,  horse  and 
driver  included,  each 
at  11-10  f.  «...    22-20 

84-00  •»  cube  water  (a 
metre  cube  =  1  ton) 
at  0-137  f .  «  .    .    .    11-50 

Turncock  (portion  of  his 
time) 200 

Total        35-70 

or  0*001116  f.  per  metre  super- 
ficial. 

It  has  been  found  that  the  streets 
of  Paris  require  to  be  watered  135 
days  on  the  average ;  the  numbers 
are  between  107  in  the  wettest 
season,  and  147  in  the  driest.  On 
the  above  average  of  135,  100  days 
require  a  double  watering.  The 
quantity  consumed  is  about  1  litre 

512 


(1*760773  pints  Eng^h)  per  metre  | 
superficial ;     l^  litre,   when   the , 
roads  are  so  very  dry  as  to  require 
a  more  abundant  watering;   and 
1*60  litre  (or  2*82  pints  English) 
in  the  Avenue  de  Nenilly.     The 
water  c^umns  are  spaced  so  as  to 
avoid  any  useless  movements  of  the 
carts ;  in  fact,  in  such  a  manner  as . 
to  allow  of  their  being  emptied  be- 
tween one  column  and  the  other. 
The  usual  distance  is  500  metres 
(about  550  yards.) 

Water-^ail,  in  navigation,    a  small 
sail  spread  occasionally  under  the 
lower  studding-sail  or    driving- 
boom,   during    a   fair  wind  and; 
smooth  sea 

WateT'^outt  a  strcmgly  agitated  mass 
of  air,  which  moves  over  tiie  sur- 
face of  the  earth,  and  revolves  on 
an  aids,  of  which  one  extremity  is 
on  the  earth  and  the  other  in  a 
cloud.    From  this  cloud  a  conti-  j 
nuationproceedsdownvrards,  which  i 
forms  the  upper  portion  of  the  ws> 
ter-spout ;  while  the  lower  portion, 
besides  air,  consists  sometimes  of 
water,  sometimes  of  solid  portions, 
according  as  the  vraterspout  passes 
over  land  or  over  water.     Some* 
have  separated  water-spouts  oven 
the  land  and  over  the  water  from  i 
each  other ;  but  this  creates  confu-  i 
sion,  for  water-spouts  have  been  ob- 
served which  were  formed  over  wa- ! 
ter,  and  advance  over  land;  andi 
vice  verad  we  have  acoonnts  of  wa- 
ter-spouts which  were  formed  over 
land,  and   afterwards    suspended 
over  the  surface  of  water. 

Water  supply  for  towns,    A  plentiful , 
supply  of  water  fitted  for  drinking, , 
culinary,  and  detergent  purposes,  • 
is  so  essentially  an  article  of  every- ' 
day  use,  that  in  all  ages,  where- 
ever  a  quantity  of  human  beings 
have  been  congregated  together, 
contrivances  have  necessarily  been 
resorted  to,  to  procure  a  supply: 
in  some  situations  wells  are  smik  to 
a  considerable  depth,  from  which 
water  is  lifted  by  means  of  buckets,  i 
pumps,  or  like  contrivances ;   in  ' 


WAT 


WATER  SUPPLY  FOR  TOWNS. 


WAT 


others,  the  rain-water  fiaUiiig  on  the 
roofe  of  houses  is  caught  and  hus- 
banded in  suitable  receptacles,  or, 
— ^as  was  much  practised  in  ancient 
times,  where  large  populations  ex- 
isted,— rivers  are  diverted  for  their 
use  from  their  natural  channels, 
and  conducted  over  yalleys  and 
through  mountains  in  artificial 
courses  having  a  small  but  con- 
tinuous decline. 

Much  has  been  written  and  said 
of  the  plentiful  supply  of  water 
brought  into  ancient  Rome  and 
towns  in  Italy,  Spain,  and  other 
places,  by  means  of  aqueducts; 
but  the  streams  supplying  these 
aqueducts  would  yield  but  little 
water  in  the  dry  summer  and 
autumn  weather,  as  is  proved  from 
the  number  of  sources  from  which 
water  was  frequently  brought  to  a 
town.  Ancient  Rome,  according  to 
some  writers,  was  supplied  from 
no  less  than  twenty  aqueducts,  all 
deriving  their  water  from  different 
sources.  These  aqueducts  were 
built  at  separate  times,  and  they 
were  doubtless  made  to  supply  a 
pressing  want ;  for  although  in  wet 
and  moderate  seasons,  probably 
one-third  this  number  would  have 
yielded  a  supply  adequate  to  the 
demand,  it  is  much  to  be  doubted 
if  this  was  the  case  in  seasons  of 
drought ;  especially  as  the  ancients 
made  no  provisions  by  means  of 
impounding  reservoirs  to  store  a 
supply  from  wet  to  dry  seasons. 

In  ancient  times,  water  was 
brought  to  a  town  from  rivers  or 
springs  more  elevated  than  the  town 
itself,  and  was  distributed  through 
fountains  to  the  inhabitants,  who 
fetched  it  in  vessels  to  their  houses. 

In  modem  times,  excessive  floods 
are  frequently  stored  in  large  re- 
servoirs, to  yield  a  supply  to  our 
towns  in  seasons  of  drought;  or 
water  from  a  neighbouring  river, 
or  from  deep  wells  sunk  in  a  sub- 
terranean reservoir,  or  water-bear- 
ing stratum  situated  below  the 
level  of  a  town,  is  frequently  lifted 


by  means  of  pumps,  worked  by 
steam  or  water  power,  through  a 
line  of  cast-iron  pipes  into  a  reser- 
voir of  sufficient  idtitude  to  admit 
of  its  being  conducted  from  thence 
through  other  pipes  to  the  highest 
house  in  a  town  ;  and  it  is  no  un- 
common thing  at  the  present  time 
to  lift  water  from  200  to  300  feet 
in  elevation  for  this  purpose. 

But  the  greatest  improvement 
lately  made  for  supplying  towns 
with  water  consists  in  the  arrange- 
ments for  conveying  it,  when  raised 
to  a  sufficient  altitude,  in  cast  iron 
or  lead  pipes,  into  the  house  of 
every  inhabitant,  even  to  the  upper 
story,  so  that  this  necessary  article 
can  always  be  secured  by  the 
turning  of  a  cock :  it  is  also  dis- 
tributed in  the  same  manner  for 
watering  roads,  and  for  use  in  case 
of  fire ;  and  it  is  principally  in  the 
excellent  system  of  distribution, 
which  perfection  in  the  art  of 
making  the  pipes  has  induced,  that 
renders  modern  water-works  supe- 
rior to  those  of  ancient  times. 

It  is  of  the  utmost  importance 
to  every  house  to  be  supplied  plen- 
tifully with  wholesome  soft-water, 
and  there  are  now  few  places  in 
which  this  cannot  be  accomplished 
at  a  cheap  rate. 

The  modem  cost  of  supplying 
water  to  a  large  town  may  now 
be  taken  at  a  low  estimate  per 
head  of  the  population   supplied, 
according  to  the  facilities  or  diffi- 
culties that  exist  for  procuring  and 
distributing  the  supply :  as  a  gene- 
ral rule,  river-water,  when  unpol- 
luted with  the  drainage  of  a  town, 
or  the  rain-water  flowing  down  the 
sides  of  steep  hills  of  a  retentive 
character,  when  properly  filtered, 
is  superior  in  quality,  and  better 
adapted  for  most   domestic  "uses 
than  the   brightest   spring-^ater, 
owing  to  its  freedom  from  saline 
matter,  which  is  usually  denoioi- 
nated  softness. 

All  rain  and  surface  water  should, 
however,  be  carefully  filtered  be- 


513 


WAT 


WATER-WHEEL. 


WATt 


fore  it  is  supplied  for  domestic  uses, 
not  only  to  free  it  from  earthy  me- 
chanicd  impurities,  but  to  rid  it  of 
organic  matter,  which  in  summer 
time  and  warm  weather  is  always 
mixed  with  such  water  in  a  greater 
or  less  degree,  and  the  presence  of 
which  renders  it  unwholesome  for 
drinking  or  culinary  uses.  It  is 
principally  owing  to  its  freedom 
from  organic  matter  that  spring- 
water,  though  usually  hard,  is  pre- 
ferred to  river-water  as  a  beverage. 

Water-wayMj  in  ship-building,  the 
|)lanks  of  the  deck  which  are  close 
to  the  timbers 

Water-wheelf  a  wheel  turned  on  its 
axis  by  the  weight  of  water  falling 
upon  its  circumference,  and  thus 
adapted  as  a  machine  for  deriving 
power  wherever  a  fall  of  water  can 
be  commanded.  For  this  purpose 
the  wheel  is  erected  in  a  vertical 
position  upon  a  horizontal  shaft  or 
axis,  and  the  periphery  of  the 
wheel  is  so  formed  that  the  great- 
est possible  effect  shall  be  received 
from  the  weight  or  gravity  of  the 
foiling  water.  To  obtain  this  ef- 
fect, the  rim  of  the  wheel  is  pro- 
vided with  small  troughs  or  buckets 
in  which  the  water  is  received,  and 
its  weight  made  active  in  carrying 
down  that  part  of  the  periphery  on 
which  the  loaded  buckets  are  situ- 
ated. As  they  approach  the  lowest 
position,  they  become  emptied,  and 
are  thus  prepared  to  be  carried  up- 
ward during  the  revolution  of  the 
wheel,  while  the  descending  buckets 
are  successively  receiving  their 
supply  from  the  fall  of  water. 
Water-wheels  are  commonly  dis- 
tinguished according  to  the  height 
of  the  fall  in  comparison  with  the 
diameter  of  the  wheel,  and  the  po- 
sition at  which  the  water  acts  upon 
the  buckets.  Thus  if  the  depth  of 
fall  equals  the  diameter  of  the 
wheel,  (besides  allowing  a  little  de- 
clivity below  the  wheel,  for  the 
ready  escape  of  the  back-water,)  so 
that  the  water  falls  on  the  highest 
point  of  its  periphery,  the  wheel  is 

514      "  ! 


said  to  be  an  'overshot'  water- 
wheeL  If  the  depth  of  fall  is  less, 
so  that  the  water  falls  upon  the 
wheel,  only  a  little  above  tiie  level 
of  its  centre,  the  wheel  is  called  a 
*  breast'  wheel.  And  if  the  depth 
of  fall  is  so  little  that  the  water 
acts  by  impulse  only  against  the 
lower  parts  of  the  wheel,  it  is  called 
an  *  undershot'  water-wheel.  Water- 
wheels  are  now  made  in  the  most 
improved  manner  of  iron,  the  arms 
behig  of  wrought  iron,  the  centres 
of  cast  iron,  and  the  buckets  of 
plate  iron.  A  water-wheel  thus 
constructed  consists  of  a  centre 
boss,  and  shaft,  arms,  backets,  and 
shrouding,  the  latter  being  the 
term  applied  to  the  rims  of  the 
wheel,  between  which  the  buckets 
are  enclosed.  In  order  to  derive 
the  greatest  working  effect  from  a 
given  fall  of  water,  the  principal 
object  is  to  shape  the  buckets  so 
that  they  shall  retain  the  water 
during  the  longest  possible  period. 
One  great  difficulty  experienced  in 
seeking  this  object  has  been  the 
opposition  exerted  by  the  air  to 
the  admission  of  the  water  into 
the  buckets;  and,  to  counteract  this 
evil,  several  methods  have  been 
devised.  The  only  efficient  remedy 
yet  introduced  is  that  invented  hy 
Mr.  Fairbaim,  and  which  he  de- 
nominates the '  Ventilating  Water- 
wheel,'  the  general  object  of  which 
is  to  prevent  the  condensation  of 
the  air,  and  to  permit  its  escape 
during  the  filling  of  the  bucket 
with  water,  as  also  its  re-admissioo 
during  the  discharge  of  the  water 
into  the  lower  mill-race.  Several 
wheels  erected  and  fitted  upon  this 
principle  have  proved  entirely  suc- 
cessful in  realizing  a  maximum  use- 
ful effect  from  a  given  fall  of  water. 
All  these  wheels  are  formed  with 
vnrought-iron  arms  radiating  from 
cast-iron  centres  to  the  periphery, 
and  so  disposed  that  the  entire 
structure  is  in  a  state  of  tension, 
and  the  motion  of  the  wheel 
being  communicated  from  internal 


WAT 


WATER-WHEELS. 


WAT 


toothed  wheels  fixed  to  the  shroud- 
ing.  As  applied  to  common  breast- 
wheels  adapted  for  falls  not  ex- 
ceeding 18  or  20  feet,  these  venti- 
lating buckets  effect  so  great  an 
improvement,  that  if  the  wheel  is 
plunged  in  back-water  to  a  depth 
of  5  or  6  feet,  its  uniform  speed  is 
not  impeded.  In  these  wheels  the 
sole  of  the  buckets  is  dose,  and  the 
tail  end  of  them  being  turned  up 
at  a  distance  of  2  inches  from  the 
back  of  the  sole-plate,  and  running 
parallel  with  it,  terminate  within 
about  2  inches  of  the  bend  of  the 
bucket,  immediately  above  it.  The 
water  in  entering  the  bucket  drives 
the  air  out  through  the  aperture 
into  the  space  belund,  and  thence 
into  the  bucket  above,  and  so  on 
in  succession.  The  converse  oc- 
curs when  the  buckets  are  emptied, 
9A  the  air  is  enabled  to  enter  as 
fast  as  the  whed  arrives  at  such  a 
position  as  to  permit  the  water  to 
escape,  (For  a  more  copious  de- 
scription see  Waier-fffheela  with 
ventilating  buckets,) 

There  are  many  cases  in  which 
it 'is  of  importance  to  know  the 
proportion  of  power  necessary  to 
give  different  degrees  of  velocity 
to  a  mill ;  but  as  the  construction 
of  mills  and  the  purposes  they 
serve  are  various,  it  is  perhaps  im- 
possible to  find  any  law  of  univer- 
sal application.  Mr.  Banks,  in 
his  *  Treatise  on  MilU/  has  drawn 
a  conclusion  which  he  appears  to 
consider  invariable,  namely,  that 
"  when  a  wheel  acts  by  gravity,  its 
velocity  will  be  as  the  cube  root 
of  the  quantity  of  water  it  re- 
ceives." 

But  supposing  a  wheel  to  raise 
water  by  means  of  cranks  and 
pumps  on  Mr.  Banks's  principle, 
Buchanan  thought  it  might  easily 
be  demonstrated,  that  by  reducing 
the  velocity  of  the  wheel  to  a  cer- 
tain degree,  the  wheel  would  ndse 
more  water  than  would  be  neces- 
sary to  move  it  at  that  velocity, — a 
thing  evidently  impossible. 

515 


In  this  view  it  would  seem  toat 
there  is  no  actual  case  in  which 
Mr.  Banks's  conclusions  win  bold 
true.  But,  however  they  may  ap- 
ply to  other  mills,  the  experiments 
of  Buchanan  seem  to  prove  iit 
least  that  they  do  not  apply  to 
cotton-mills.  On  the  ground  of 
some  experiments  made  at  differ- 
ent times,  and  vnth  aU  the  atten- 
tion possible,  did  he  presume  to 
call  in  question  an  authority  for 
which  the  highest  respect  is  enter- 
tained. 

In  January,  1796,  he  measured 
the  quantity  of  water  the  Rothesay 
o]d cotton-mill  required;  first,  when 
going  at  its  common  velocity,  and 
secondly,  when  going  at  half  that 
velocity.  The  result  was,  that  the 
last  required  just  half  the  quantity 
of  water  which  the  first  did.  It 
is  to  be  observed,  that  in  these  ex- 
periments the  quantities  of  water 
were  calculated  from  the  heads 
of  water  and  apertures  of  the 
sluices. 

From  these  experiments  he  in- 
ferred, **  that  the  quantity  of  water 
necessary  to  be  employed  in  giving 
different  degrees  of  velocity  to  a 
cotton-mill  must  be  nearly  as  that 
velocity." 

He  was  satisfied  with  this  expe- 
riment, and  the  inference  drawn 
from  it,  till  some  gentlemen  well 
acquainted  with  the  theory  and 
practice  of  mechanics  expressed 
then:  doubts  on  the  subject.  He 
had  then  recourse  to  another  ex- 
periment, which  he  considered  less 
liable  to  error  than  the  former. 

The  water  which  drives  the  old 
cotton-mill  falls  a  little  below  it 
into  a  perpendicular-sided  pond, 
which  serves  as  a  dam  for  a  com- 
null  at  some  distance  below  it. 
To  ascertain,  therefore,  the  propor- 
tional quantities  of  water  used  by 
the  old  mill,  nothing  more  was 
necessary  than  to  measure  the  time 
the  water  took  to  rise  to  a  certain 
height  in  that  pond ;  and  accordr 
ingly,  on  the  1st  of  May,  1798,  he 


WAT 


WATER-WHEELS. 


WAT 


made  the  experiments  noted  in  the 
following  Table : 

NnmlMr  of  experi- 
ments   1       S       S       4 

Reyolutioni  of  one  of 
ttie  upright  shafte 
per  nimute   .    .    •     46     46     S4     S3 

Biae  of  water  in  the 
pond  in  inches  .    .      S       6       6       6 

"nine  in  minutes  and 
•econdi     ....  6*58  6*57  14*46  Ift'O 

The  first  and  second  experiments 
were  made  with  the  mill  at  its 
common  velocity;  the  third  and 
fourth  at  nearly  half  that  velocity. 

The  time  which  the  mill  re- 
quired to  use  the  same  quantity  of 
water  in  these  experiments  may 
be  taken,  in  round  numbers,  as 
follows:  the  proper  velocity  at  7 
minutes,  and  half  that  velocity  at 
15  minutes. 

The  result  of  these  experiments 
approaches  very  nearly  to  that  of 
1796.  The  difference  may  be  ac- 
counted for  by  the  small  degree  of 
leakage  which  must  have  taken 
place  at  the  sluices  on  the  lower 
end  of  the  pond;  and  the  time 
being  greater  in  the  third  and 
fourth  experiments,  the  leakage 
would  of  course  be  greater. 

Smeaton  and  others  have  proved 
in  a  very  satisfactory  manner,  that 
**  the  mechanical  power  that  must 
of  necessity  be  employed  in  giving 
different  degrees  of  velocity  to  the 
same  body,  must  be  as  the  square 
of  that  velocity.''  But  it  appeared 
to  Buchanan,  that  the  result  of  the 
above  experiments  may  be  easily 
reconciled  to  this  proposition,  by 
considering  what  Smeaton  says 
immediately  afterwards : — "  If  the 
converse  of  this  proposition  did 
not  hold  true,  viz.  that  if  a 
body  in  motion,  in  being  stopped, 
would  not  produce  a  mechanical 
effect  equal  or  proportional  to  the 
square  of  its  velocity,  or  to  the 
mechanical  power  employed  in 
producing  it,  the  effect  would  not 
correspond  with  its  producing 
cause.''  It  is  to  be  observed, 
that  Smeaton's  experiments  were 

516 


made  on  the  velocity  of  heavy 
bodies,  free  from /riction  and  other 
causes  of  resistance ;  but  in  mills 
there  is  not  only  friction,  but  ob- 
stacles, to  be  removed :  and  ex- 
periments made  on  friction  have 
proved  that  the  friction  of  many 
kinds  of  bodies  increases  in  direct 
proportion  to  their  velocity.  Bm 
the  velocity  of  a  ootton-mill  at 
work  may  be  considered  as  a  me- ' 
chanical  effect;  and,  if  so,  must 
correspond  with  its  producing 
cause. 

The  preceding  experiments  on 
the  Rothesay  miU  are  undoubtedly 
correct  and  consistent  with  the 
principles  of  motion  and  power., 
and  also  with  the  experiments  of 
Smeaton  on  mills  and  mechanical 
power. 

The  mechanical  power  is  as 
the  quantity  of  water  on  the 
wheel,  multiplied  into  its  velo- 
city when  the  wheel,  fall,  and 
other  circumstances  remain  the 
same;  and  since  the  mechanical' 
effect  is  measured  by  the  resistaoce 
multiplied  into  the  velocity  of  the 
working  point  when  the  friction  is 
constant,  if  the  quantity  of  water  be 
diminished  by  its  half,  either  half 
the  resistance,  or  half  the  velocitT 
with  which  it  is  overcome,  must  be 
taken  away,  otherwise  there  will 
not  be  an  equilibrium  between  the 
power  and  effect.  But  at  the  same 
time  it  is  to  be  observed,  than  as 
increased  velocity  lessens  the  fric- 
tion of  the  intermediate  machinery, 
and  consequently  a  greater  effect 
would  be  produced  by  the  greater 
velocity,  as  appears  to  be  the  case 
by  the  experiments.  There  is  not, 
however,  in  the  detail  of  these  ex- 
periments, sufficient  data  by  which 
it  becomes  easy  to  arrive  at  any 
useful  conclusion. 

Roberton,  an  engineer  of  some 
eminence,  made  observations  on 
these  experiments,  alleging  that 
the  conclusions  of  Banks  give  most 
satisfactory  evidence  that  particular 
care  and  judgment  are  necessary  in 


WAT 


WATER-WHEELS. 


WAT 


making  Buch  trials.  It  appeared 
to  Roberton,  that  the  wrong  con- 
dusions  which  have  been  drawn 
by  many  writers  on  this  subject, 
have  wholly  arisen  from  misappre- 
hending some  of  Sir  Isaac  Newton's 
fundamental  principles  of  mecha- 
nics, and  from  a  love  of  establish- 
ing theoretical  expressions  rather 
than  strict  observations  of  the  in- 
variable laws  of  nature, — expres- 
sions such  as  these,  viz.  quantity  of 
motion,  inatantaneous  inyntbe. 

Taking  a  constant  portion  of 
time  (viz.  a  second)  to  be  the 
measure  of  a  body,  and  an  instant 
to  be  measure  of  the  efflect  it  pro- 
duces; or  by  taking  time  as  the 
measure  of  the  cause,  and  space  as 
the  measure  of  the  effect, — as  to 
an  ifutantaneoui  effect,  Roberton 
argues  that  it  is  an  absurdity 
in  itself,  as  well  as  in  mechanics, — 
we  can  form  no  idea  of  a  body  put 
into  motion,  without  the  acting 
power  or  body  act  upon  the  body 
put  into  motion  for  some  timet  and 
also  over  some  tpaee;  and  to  sup- 
pose otherwise,  leads  us  entirely 
out  of  the  sound  principles  of 
mechanics. 

In  mechanics  every  effect  is  equal 
to  its  producing  cause.  In  the  case 
ofapoweractingonabodyproducing 
motion,  and  also  this  body  acting 
against  another  power  which  re- 
tards its  motion,  if  the  causes  of 
action  and  resistance  are  each 
measured  by  the  time  the  motions 
are  produced  and  retarded,  the 
result  will  be  equaL 

If  they  be  measured  by  the 
tpace  over  which  they  act,  the  re- 
sults will  be  equal ;  and  this  is  an 
universal  principle,  whether  ap- 
plied to  accelerating  power  and 
motion,  as  gravity,  &c.,  or  to  ma- 
chines which  act  constantly  and 
uniformly.  Yet,  in  the  case  of 
uniform  motion,  space  or  time  may 
be  used  at  pleasure ;  as  from  the 
uniformity  of  space  and  time  they 
become  fk  common  measure. 

To  illustrate  this,  suppose  the 

"Tit 


A    Q 


I 


body  A  acted  upon  by  the  power 
of  gravity  through  the  space  a  b, 
in  a  portion  of  time  which  we  will 
call  one.  When  it  arrives  at  b,  it 
meets  vrith  another  medium  of  re- 
sistance, which  is  ten  times  greater 
than  the  former :  the  body 
A  will  be  resisted  in  pro- 
.  portion  to  the  cause  of  ac- 
tion and  resistance;  that 
is  to  say,  if  the  time  of 
action  were  one  second, 
the  time  of  resistance  wiU 
be  one-tenth  of  a  second, 
and  the  distance  a  b  will 
be  to  the  distance  b  c  as 
tentoone;  so  that  whether 
epaee  or  time  be  taken  as 
the  measure  of  action,  the 
same  must  be  taken  for 
the  measure  of  the  effect, 
tohavetheresults  propor- 
tionate and  equaL  But 
if  the  cause  be  measured 
by  time,  and  the  effect  by 
epace,  the  results  will  be 
as  the  squares  of  the  time, 
or,  which  is  the  same 
thing,  as  the  squares  of  the  ve- 
locity. 

Thus,  suppose  a  body  in  motion, 
with  a  velocity  of  one,  has  a  power 
to  penetrate  into  a  bank  of  earth 
1  foot :  if  the  same  body,  with  a 
velocity  of  two,  strike  the  bank,  it 
vrill  penetrate  to  the  depth  of  4 
feet;  for  the  velocity  is  double, 
and  the  time  of  action  is  double, 
and  therefore  the  results  will  be 
compounded  of  both,  that  is,  as  the 
square  of  the  velocity. 

From  the  above  it  may  be  in- 
ferred that  if  equal  bodies  be  acted 
upon  by  unequid  powers,  the  time 
requisite  to  produce  an  equal  mo- 
tion will  be  reciprocally  propor- 
tionate to  the  powers ;  that  is  to 
say,  if  a  power  of  ten  act  upon  a 
body  for  one  second  (^  time,  and 
the  power  of  one  act  upon  an  equal 
body  for  ten  seconds,  they  will  pro- 
duce   equal   velocities.      But  the 
spaces  through  which  the  bodies  are 
carried  are  very  unequal,  being  as 


WAT 


WATER-WHEELS. 


WAT 


I 


ten  to  one ;  and  if  the  square  roots 
of  the  powers  producing  the  effects 
be  taken,  that  will  give  the  times 
they  take  in  carrying  the  body 
acted  upon  through  equal  spaces. 

But  it  is  obTious  this  doctrine 
has  no  more  to  do  with  the  ope- 
ration of  machines  than  to  supply 
their  first  starting  from  rest  to  the 
motion  necessary  for  working. 
When  this  is  acquired,  the  power 
applied  and  the  power  of  resistance 
balance  each  other,  and  whatever 
be  the  motion  the  machine  moves 
at,  the  same  power  will  carry  it  on, 
(if  it  be  upheld,)  provided  the 
machine  act  in  such  a  manner  as 
not  to  accumulate  resistance  by 
the  accumulation  of  motion,  which 
is  the  case  in  forcing  fluids  through 
pipes,  ^c.  In  cases  of  this  kind, 
the  nature  of  the  machine  must  be 
particularly  kept  in  view,  and  no 
law  whatever  adopted  to  explain 
the  resistance  the  acting  body  meets 
with,  but  what  is  simply  deduced 
from  the  very  machine  which  is 
under  consideration ;  but,  in  most 
cases,  any  machine  may  be  con- 
sidered as  acting  purely  on  a  sta- 
tical principle.  The  raising  of 
weights,  or  overcoming  friction, 
Roberton  considers  purely  as  act- 
ing on  that  principle;  and  when 
the  power  of  action  is  equal  to  the 
resisting  power,  the  machine  is  in- 
different to  motion  or  rest.  If  the 
machine  be  at  rest,  the  power  will 
not  move  it,  being  a  balance  to  the 
resistance.  If  the  machine  be  set 
in  motion,  the  power  will  keep  it 
in  the  same  motion,  (provided  the 
power  be  upheld,)  the  same  as 
equal  weights  hung  over  a  pulley, 
or  in  the  opposite  scales  of  a  beam. 
If  they  be  at  rest,  they  will  remain 
so ;  and  if  they  be  put  in  motion, 
they  will  endeavour  to  persevere  in 
the  same. 

The  above  doctrine  of  a  statical 
principle  is  proved  in  the  most 
satisfactory  manner  by  the  experi- 
ments made  at  the  old  mill  of 
Rothesay,  the  motion  of  the  water- 

518 


wheel  being  exactly  proportional 
to  the  quantity  of  water  expended, 
and  therefore  an  exact  and  equal  j 
load  upon  the  wheel ;  that  is  to  > 
say,  the  buckets  were  equeOy  fuO  \ 
when  the  mill  moyed  at  its  ordi- 1 
nary  motion,  or  at  hiUf  that  mo-  \ 
tion. 

The  effect,  therefore,  of  letting 
more  water  on  a  wheel  is  not  to 
lodge  a  greater  quantity  in  the 
buckets,  but  to  supply  the  same 
quantity  when  the  wheel  is  in  a 
greater  motion. 

Banks,  however,  made  his  ex- 
periments agree  with  his  theory, 
yet  Roberton  took  no  trouble  in 
inquiring  into  them,  alleging  it 
would  be  to  little  purpose  to  have 
done  so. 

"Suffice  it  to  Bay,"  he  adds, 
'<  that  the  very  small  quantities  of 
water  which  Banks  made  use  o(, 
and  the  slowness  of  the  motion  of 
his  wheel  in  his  experiments,  give 
no  ground  for  placing  the  smallest 
dependence  on  them;  and  when 
compared  with  the  more  judicious 
and  accurate  experiments  of  Smea- 
ton,  they  dwindle  into  contempt." 
Rob^^n  further  says,  that 
**  Smeaton,  in  running  his  wheel 
at  nearly  3  feet  in  the  second, 
brought  it  nearly  to  a  maxinnun* 
and  lost  but  about  one-fourth  or 
one-fifth  of  the  original  effect  (al- 
luding to  his  overshot  wheds). 
Banks,  at  his  highest  motion,  run 
his  wheel  about  1  fSoot  in  the  se- 
cond, and  reducing  it  to  one-half 
of  that  motion,  the  same  quantity 
of  wrater  then  expended  was  ca- 
pable of  performing  four  times  the 
work;  and  by  deduction  froo 
thence,  it  appears  plain  that  his 
wheel  (from  his  own  theory)  would 
perform  about  twenty  times  the 
quantity  of  work  which  Smcatoa's 
could  perform  with  the  same  quan- 
tity of  water,  and  about  sixteen 
times  more  than  nature;  so  that 
the  observation  (alluding  to  the 
theory  of  Banks)  is  very  just  in 
saying  that,  by  redudng  the  mo- 


WAT 


WATER-WHEELS,  OVERSHOT. 


WAT 


tion  of  the  wheel,  it  is  demon- 
strable it  would  raise  more  water 
than  supply  itself." 
Water-wheels  (Overshot),  The  best 
water-wheel  is  that  which  is  cal- 
culated to  produce  the  greatest 
effect  when  it  is  supplied  by  a 
stream  furnishing  a  given  quantity 
of  water  with  a  given  fall. 

The  mechanical  effect  depends 
on  the  )>roportion  of  the  wheel's 
diameter  to  the  height  of  the  fall, 
and  on  the  velocity  of  the  circum- 
ference of  the  wheel.     These  are 


the  two  principal  parts  to  be  con- 
sidered in  the  theory  of  wheels, 
but  there  are  also  some  other  points 
which  ought  to  be  attended  to,  be- 
cause the  effect  is  much  decreased 
when  they  are  neglected. 

Of  the  proportion  of  the  radius 
of  the  water-wheel  to  the  height  of 
thefaU.^Let  ab  c  d  be  the  wheel, 
and  E  A  the  depth  of  the  buckets ; 
then,  according  to  experiments  on 
water-wheels,  it  appears  that  the 
rotatory  form  of  the  water  in  the 
buckets  is  nothing  at  c  and  J,  and 


that  it  increases  nearly,  if  not  ac- 
curately, in  the  direct  ratio  of  the 
distance  from  c  or  J,  and  is  greatest 
at  A.  That  is,  the  force  at  any 
point  a  in  a  direction  ea,  or  per- 
pendicularly to  the  radius,  is  as 
a  e. 

A  slight  consideration  of  the 
figure  is  sufficient  to  demonstrate 
that  the  wheel  will  not  produce 
the  greatest  effect  when  it  receives 

519 


the  "water  at  the  upper  point  c,  am 
that  there  must  be  considerabl 
advantage  in  making  the  whec 
of  a  greater  diameter,  so  that  i 
may  receive  the  water  at  the  sam 
point  between  a  and  c,  the  poin 
which  will  insure  the  greatest  ef 
feet  thus  calculated. 

Let  c  ss  that  portion  of  the  cii 
cumference  which  is  to  be  loadei 
with  water ;  and  s  ^  the  arc  con 


WAT 


WATER-WHEELS,  OVERSHOT. 


WAT 


prehended  between  the  point  where 
the  water  flows  upon  the  wheel 
and  the  horizontal  line  ba;  also 
make  b  »  the  area  of  the  stream 
supplying  the  buckets.  Then  the 
solid  which  represents  the  effective 
force  will  be 


'  -  C-^' 


which  is  to  be  the  greatest  possible ; 
or 

c  — * 

K  a  maximum.  By  the  principles 
of  maxima  and  minima  this  takes 
place  when 

jp  =  c(l->/i)or*«-2929e. 

Accordingly  the  arc  c  —  jr  must  be 
the  quadrant  dg  or  90^,  and  the 
arc  jr  s  37-27®. 

Hence  we  have  this  important 
practical  maxim.  A  water-wheel 
will  produce  the  greatest  effect 
when  the  diameter  of  the  wheel  is 
proportioned  to  the  height  of  the 
fall,  so  that  the  water  flows  upon 
the  wheel  at  a  point  about  52f° 
distant  from  the  summit  of  the 
wheeL 

If  r  be  the  radius  of  the  wheel 
to  the  extreme  part  of  the  bucket, 
and  h  the  effectiye  height  of  the 
fall,  then  A  =  r  (I  +  sin.  37i),  or 
h  =  1-605  r ;  for  the  sin.  37i  «  605. 
Also  '623  h^r.  Therefore,  when 
the  effective  height  of  the  fall  is 
determined,  the  radius  of  the  wheel 
is  easily  calculated.  When  the  ef- 
fective fall  is  f  of  the  whole  fall,  if 
we  make  h  the  whole  fall,  r  « 
*554  h,  or  1*108  h  »  the  diameter 
of  the  wheel. 

The  effective  height  of  the  fall 
is  less  than  the  true  height  by  as 
much  as  is  necessary  for  giving  the 
water  the  same  velocity  as  the 
wheel  before  it  flows  upon  it. 

In  low  falls  a  wheel  would  work 
with  advantage  in  a  considerable 
depth  of  tail-water,  provided  the 

520 


buckets  were  of  a  suitable  form  for 
moving  through  the  water,  and  the 
effective  fall  made  through  a  very 
accurate  sweep,  so  that  the  sweep, 
and  not  the  form  of  the  bucket, 
should  confine  the  water  upon  the 
wheel. 

Of  the  velocity  of  the  drem- 
firence  of  the  wheel  to  ffrodnce  a 
nuunmum  effect. — It  is  neoessiiy 
to  premise,  that  the  velocity  vith 
which  the  water  flows  upon  the 
floating  boards  or  buckets  is  con- 
sidered to  be  equal  to  the  vdocitr 
of  the  wheel,  and  to  strike  against 
the  floats  as  nearly  as  possible  is 
the  direction  of  the  motion  of  the 
wheeL 

Let  X  be  that  part  of  the  M 
which  gives  the  necessary  velodtr 
V  to  the  water,  when  the  effect 
is  a  maximum;  v  will  then  be 
the  velocity  of  the  drcumfereDce 
of  the  wheel.  Also,  make  «  = 
that  part  of  the  fall  which  would 
correspond  to  the  velocity  of  the 
circumference  of  the  wheel  when 
the  power  would  be  eqnal  to 
the  friction  of  the  loaded  macbiiie 
only;  or  when  the  useful  effect 
would  be  nothing.  Now  if  A  he 
the  whole  fall,  the  effective  force 
of  the  water  on  the  wheel  will 
always  be  proportional  to  A--'< 
when  the  effect  is  a  maziminD; 
and  to  A  — a,  when  the  useful 
effect,  or  work  done,  is  nothing. 

Hence  v  (A  —  jr  —  A  -  a)  most 
be  a  maximum ;  or  t;  (a  —  *)  = ' 
max.;  but  v  «  ***,  therefore  / 
(a  —  ar)  «  a  max.,  which,  according 
to  the  rules  of  maxima  and  minima, 
takes  place  when  a^Zx, 

It  is  evident  that  the  value  of « 
must  entirely  depend  on  the  nature 
of  the  machine ;  for  if  there  be  many 
moving  parts  between  the  power 
and  the  resistance,  the  firiction  wiD 
be  greater,  and  consequently  a  will 
be  less.  The  machine  must  be 
very  simple  indeed,  if  the  firiction 
be  less  than  one-half  the  moving 
power,  and  it  will  often  amount  to 


WAT 


WATER  WHEELS,  OVERSHOT. 


WAT 


two-thirds  of  it.    If  we  suppose  it 
to  be  two-thirds,  then 

h 

and  consequently 

h 


and 


»=  V 


,/  64i  h 


2-67  a/A. 


Hence,  when  the  friction  amounts 
to  two-thirds  of  the  moving  power, 
the  Telocity  of  the  circumference  of 
an  overshot  wheel  in  feet  per  se- 
cond, should  be  2*67  times  the 
square  root  of  the  whole  height  of 
tl^  fall,  in  feet. 

Again,  that  part  of  the  fiiU  is  to 
be  determined,  which  will  give  the 
water  the  same  velocity  as  the 
wheel;  and  since 


as—,  and  3^  =^  a, 


we  have 


h 

X  =  — ' 
9 


Hence,  when  the  friction  is  two- 
thirds  of  the  power,  that  part  of 
the  fall  which  will  give  the  water 
the  proper  velocity  is  one-ninth 
of  the  whole  height. 

These  results  may,  then,  be  use- 
fully compared  vdth  the  experi- 
ments of  Smeaton;  at  the  same 
time  it  is  obvious  that  his  experi- 
ments were  not  adapted  for  arriv- 
ing at  general  conclusions,  because 
the  water  was  always  delivered 
upon  the  same  wheel:  for  it  is 
clear,  from  the  preceding  investi- 
gation, that  every  particidar  wheel 
must  have  its  particular  maximum. 

In  Smeaton's  experiments  on 
overshot  wheels,  the  wheel  was  2 
feet  in  diameter;  therefore  the 
height  of  the  fall  should  be  2\  feet. 
Now  the  square  root  of  2\  is  1*5 ; 
and  1-5  X  2-67  =  4*005,  that  is, 

521 


the  velocity  of  the  wheel  should  be 
4  feet  per  second;  or  it  should 
make  38  turns  per  minute.  Smea- 
ton infers  that  "  the  best  velocity 
for  practice  '*  will  be  when  a  wheel 
of  2  feet  diameter  makes  30  revo- 
lutions per  minute.  (Miscellaneous 
Papers,  p.  51.)  But  his  model  had 
much  more  friction  in  proportion 
to  the  effective  force  of  water  on 
the  wheel  than  two-thirds,  here 
calculated  upon.  When,  however, 
the  calculation  is  made  according 
to  the  friction  of  Smeaton's  model, 

V  =  2*4  VT; 

and  the  velocity  of  the  model  wheel 
would  come  out  3*6  feet  per  second, 
or  34  turns  per  minute.  This  ve- 
locity vdll  perhaps  apply  correctly 
enough  to  overshot  wheels,  where 
the  water  flows  on  at  the  summit, 
and  to  rough-made  machinery ;  but 
the  former  calculation  is  that  which 
appears  to  be  most  correct  for  the 
improved  kind  of  wheels  here 
pointed  out.  It  is  to  be  under- 
stood, that  the  friction  allowed  for 
includes  all  the  kinds  of  resistance 
and  loss  of  force  which  lessen  the 
useful  effect,  as  well  as  the  resist- 
ance of  the  rubbing  surfaces,  pro- 
perly called  friction.  Many  persons 
may  think  that  two-thirds  of  the 
effective  force  is  greatly  too  much 
to  be  lost ;  it  will  be  well  if  it  draw 
their  attention  to  lessening  the 
stress  on  every  part  of  the  machi- 
nery, and  to  the  importance  of 
having  few  rubbing  surfaces,  and 
other  causes  of  resistance. 

On  computing  the  power  ofwer^ 
shot  water-wheels. — ^In  determining 
the  proportion  of  the  radius  of  the 
wheel  to  the  height  of  the  fall,  an 
equation  is  given  for  the  effective 
force.  Resuming  that  equation,  we 
have 

=  the  effective  force  of  the  water, 
and 


WAT 


WATER-WHEELS,  OVERSHOT. 


WAT 


c2  -  2xh 


^  its  mechanical  power.  But  the 
quantity  of  water  expended  in 
maintaining  this  power  will  be  6  0. 
Hence,  the  quantity  of  water  ex- 
pended is,  to  its  mechanical  power, 
as 


1  :4 


(t^)- 


When  the  wheel  is  supplied  at 
the  summit,  x  ^\c\  and  there- 
fore the  quantity  of  water  ex- 
pended is  to  its  mechanical  power 
as  1  :  I  c.  Or  the  power  is  equal 
to  half  the  weight  of  water  sup- 
plied to  the  wheeL 

The  same  relation  takes  place 
when  jr »  0 ;  that  is,  when  the 
wheel  is  supplied  at  the  height  of 
the  axis.  Hence,  when  the  radius 
of  a  breast-wheel  is  equal  to  the 
effectiTe  height  of  the  fall,  its 
power  will  be  the  same  as  that  of 
an  oyershot  wheel  supplied  at  the 
summit. 

When  the  wheel  is  supplied  at 
the  point  which  produces  the 
greatest  effect,  x  »  *2929  c ;  and 
consequently  the  quantity  of  water 
expended  is  to  its  mechanical 
power  as  1  :  0*5857  c:  this  effect 
is  greater  than  when  the  wheel  is 
supplied  at  the  summit  in  the  ratio 
of  11714:1. 

These  comparisons  will  conyey 
some  useful  information  to  many 
readers ;  and  they  may  sometimes 
suggest  to  scientific  writers  the 
advantage  of  studying  the  actual 
nature  of  machines ;  for  relations 
so  extremely  obvious  and  simple 
could  never  have  been  overlooked 
by  any  one  who  might  have  con- 
descended to  examine  the  subject. 

The  power  of  a  water-wheel  may 
be  considered  under  two  points  of 
view ;  each  of  which  has  its  pecu- 
liar use.  If  we  wish  to  compare  it 
with  any  other  first  mover,  then 
we  shall  have  to  calculate  its  me- 
chanical power.     But  when  it  is 

522  ^^ 


desirable  to  compute  the  resistance 
it  will  overcome  at  the  work'mg 
point,  the  effective  force  should  be 
calculated. 

When  the  water  flows  upon  the 
wheel,  either  at  or  above  the  axis, 
the  mechanical  power  is 

\hv 

C  —  X 

cubic  feet  of  water,  or 

31*25  ft  r^: fts.; 

where  ft  «  is  the  quantity  of  water 
expended  in  a  second,  in  cubic  feet; 
c  the  part  of  the  circumference  be- 
tween the  lowest  point  of  the  wheel 
and  the  place  where  the  water 
flows  upon  it,  in  feet ;  and  x  the 
part  of  the  circumference  betfeen 
the  point  which  is  level  with  the 
axis,  and  that  where  the  water 
flows  upon  the  wheel,  in  feet. 

Suppose  the  mechanical  power 
of  a  horse  is  estimated  at  200  fts^ 
moving  with  a  velocity  of  ^  feet 
per  second,  then  a  water-wheel 
wrill  be  equal 


31'25ftp(c»-2jg« 
200  X  3|  (c  -  x) 


horses; 


•00426ft»(cS-2a») 


c  —  X 


horses. 


When  the  water  flovTs  on  either 
at  the  summit  or  at  the  level  of  the 
axis,  the  mechanical  power  is 
31-25  hve  lbs.,  or  it  is  «  000426 
bvc  horses. 

When  the  water  flows  on  at  52| 
degrees  distant  from  the  summit, 
the  mechanical  power  is  37*192 
bvc  lbs.,  or  »  *005  b  v  e  horses. 
Since  in  this  case,  c  »  127^  degrees 
of  the  circumference,  we  have  e  - 
127i  X  0174533  r;  and  «  r« 
•554  A;  and  V  «  2*67  ^ h\  b; 
substituting  these  quantities,  we 

have  122*176  ftAl  lbs.  :=  the  me- 
chanical power;  or  *0164  hh*- 
the  number  of  horses,  where  A  =- 
the  whole  height  of  the  fall,  in  feet, 


WAT 


WATER-WHBELS,  VENTILATED. 


WAT 


and  b  =  the  area  of  the  aperture 
through  whiich  the  water  flows 
upon  the  wheel,  in  feet. 

The  effective  force  is  31*25  be 
fts.  when  the  water  flows  on  either 
at  the  sommit  er  at  the  level  of 
the  axis. 

When  the  water  flows  on  at  52} 
degrees  distant  from  the  summit  of 
the  wheel,  the  effective  force  is 
37*192  be  lbs.  or  45*746  b  h  lbs. 

Ofthepower  of  breast-wheeb. — 
When  the  water  flows  on  helow  the 
level  of  the  axis  of  the  wheel,  it 
may  be  termed  a  breast-wheel. 

Let  y  be  the  distance  below  the 
axis  measured  on  the  circumference, 
thea 

c^bv 
2  (c  +  y) 

equal  the  mechanical  power  in 
cubic  feet  of  water,  or 


31*25  c«  ft  g 
c  +  y 


lbs. 


When  y  '^  Ct  the  power  will  be  re- 
duced one-half,  and  when y  ^2e, 
it  will  be  reduced  two-thirds,  and 
soon. 

If  we  assume  that  the  mechani- 
cal power  of  an  undershot  wheel  is 
half  that  of  an  overshot  one  **  under 
the  same  eircumstances  of  quantity 
and  fall ;"  then  it  wiU  be  an  ad- 
vantage to  employ  an  undershot 
wheel  whenever  the  fall  is  less  than 
three-tenths  of  the  radius  of  the 
wheel.  But  since  the  radius  of 
the  wheel  may  in  many  cases  be 
diminished,  it  does  not  appear  to 
be  desirable  to  employ  an  under- 
shot wheel  in  any  case,  except  where 
the  quantity  of  water  is  great  and 
the  fall  inconsiderable. 
Water-wheeb  with  ventilated  Buckets, 
Since  the  time  of  Smeaton's  expe- 
riments in  1759,  little  or  no  im- 
provement has  been  made  in  the 
principle  on  which  water-wheels 
have  been  constructed.  The  sub- 
stitution, however,  of  iron  for  wood, 
as  a  material  for  their  construction, 
has  afforded  opportunities  for  ex- 

523 


tensive  changes  in  their  forms,  par- 
ticularly in  the  shape  and  arrange- 
ment of  the  buckets,  and  has  given, 
altogether,  a  more  permanent  and 
lighter  character  to  the  machine 
than  had  previously  been  attained 
vdth  other  materials.  A  curvili- 
near form  of  bucket  has  been  gene- 
rally adopted,  the  sheet  iron  of 
which  it  is  composed  affording 
facility  for  being  moulded  or  bent 
into  the  required  shape. 

From  a  work  entitled  'Meca- 
niques  et  Inventions  approuv^s  par 
TAcad^mie  Boyale  des  Sciences,' 
published  at  Paris  in  1735,  it  ap- 
pears, that  previous  to  the  com- 
mencement of  the  last  century, 
neither  the  breast  nor  the  overshot 
water-wheels  were  much  in  use,  if 
at  all  known ;  and  at  what  period, 
and  by  whom  they  were  introduced, 
is  probably  equally  uncertain.  The 
overshot  wheel  was  a  great  im- 
provement, and  its  introduction  was 
an  important  step  in  the  perfecting 
of  hydraulic  machines ;    but  the 
breast-wheel,    as   now    generally 
made,  is  a  still  further  improve- 
ment, and  is  probably  better  calcu- 
lated for  effective  duty  under  the 
circumstances  of  a  variable  supply 
of  water,  to  which  almost  every 
description  of  water-wheel  is  sub- 
jected.   Improvements  have  taken 
place  during  the  last  and  the  pre- 
sent centuries.    The  breast-wheel 
has  taken  precedence  (rf  the  over- 
shot wheel,  not  so  much  from  any 
advantage  gained  by  an  increase  of 
power,  on  a  given  fall,  as  from  the 
increased  facilities  which  a  wheel 
of  this  description,  having  a  larger 
diameter  than  the  height  of  the 
fall,  affords  for  the  reception  of  the 
water  into  the    chamber  of  the 
bucket,  and  also  for  its  final  exit  at 
the  bottom. 

Another  advantage  of  the  in- 
creased diameter  is  the  comparative 
ease  with  which  the  vheel  over- 
comes the  obstruction  of  back- 
water. The  breast-wbeel  is  not 
only  less  injured  from  the  effects 


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WATER-WHEELS,  VENTILATED. 


of  floods,  but  the  retarding  force  is 
overcome  with  greater  ease,  and 
the  wheel  works  for  a  longer  time 
and  to  a  much  greater  depth  in 
back-water. 

The  late  Dr.  Robison,  Professor 
of  Natural  Philosophy  in  the  Uni- 
versity of  Edinburgh,  in  treating  of 
water-wheels,  says,  "There  fre- 
quently occurs  a  difficulty  in  the 
making  of  bucket-wheels,  when  the 
half-taught  millwright  attempts  to 
retain  the  water  a  long  time  in  the 
buckets.  The  water  gets  into  them 
with  a  difficulty  which  he  cannot 
account  for,  and  spills  all  about, 
even  when  the  buckets  are  not 
moving  away  from  the  spout.  This 
arises  frt>m  the  air,  which  must 
find  its  way  out  to  admit  the  water, 
but  is  obstructed  by  the  entering 
water,  and  occasions  a  great  sput- 
tering at  the  entry.  This  may  be 
entirely  prevented  by  making  the 
spout  considerably  narrower  than 
the  wheel:  it  will  leave  room  at 
the  two  ends  of  the  buckets  for  the 
escape  of  the  air.  This  obstruction 
is  vastly  greater  than  one  would 
imagine ;  for  the  water  drags  along 
with  it  a  great  quantity  of  air,  as  is 
evident  in  the  water-blast,  as  de- 
scribed by  many  authors.^' 

In  the  construction  of  wheels  for 
high  falls,  the  best  proportion  of 
the  opening  of  the  bucket  is  found 
to  be  nearly  as  five  to  twenty-four ; 
that  is,  the  contents  of  the  bucket 
being  24  cubic  feet,  the  area  of  the 
opening,  or  entrance  for  the  water, 
would  be  five  square  feet.  In 
breast -wheels  which  receive  the 
water  at  the  height  of  10°  to  12° 
above  the  horizontal  centre,  the 
ratio  should  be  nearly  as  eight  to 
twenty-four,  or  as  one  to  three. 
With  these  proportions,  the  depth 
of  the  shrouding  is  assumed  to  be 
about  three  times  the  width  of  the 
opening,  or  three  times  the  dis- 
tance from  the  lip  to  the  back  of 
the  bucket,  as  from  a  to  b,  fig.  1, 
the  opening  being  5  inches,  and 
the  depth  of  the  shroud  15  inches. 

524 


Fig.  1. 


wat' 


For  lower  falls,  or  in  those  wheeb 
which  receive  the  water  below  the 
horizontal  centre,  a  larger  opening ; 
becomes  necessary  for  the  recep- ' 
tion  of  a  large  body  of  water,  and 
its  final  discharge. 

In  the  construction  of  water- 
wheels,  it  is  requisite,  in  order  to  at- 
tain the  maximum  efirect,tohave  the 
opening  of  the  bucket  sufficiently 
large  to  allow  an  easy  entrance 
and  an  equally  free  escape  for  the 
water,  as  its  retention  in  the  bucket 
must  evidently  be  injurious,  when 
carried  beyond  the  vertical  centre,  i 

Dr.  Robison  further  obsenres,  | 
"  There  is  another  and  very  sen- ' 
ous  obstruction  to  the  motion  of 
an  overshot  or  bucketed  wheel.  { 
When  it  moves  in  back-water,  it ' 
is  not  only  resisted  by  the  water ! 
when  it  moves  more  slowly  than 
the  wheel,  which  is  very  frequently 
the  case,  but  it  lifts  a  great  deal  in 
the  raising  buckets.  In  some  par- 
ticular states  of  back-water,  the 
descending  bucket  fills  itself  com- 


WAT 


WATER-WHEELS,  VENTILATED. 


WAT 


pletely  "with  water,  and  in  other 
cases  it  contains  a  very  considerable 
quantity,  and  air  of  common  den- 
sity; while  in  some  rarer  cases  it 
contains  less  water,  with  air  in  a 
condensed  state.  In  the  first  case, 
the  rising  bucket  must  come  up 
filled  with  water,  which  it  cannot 
drop  till  its  mouth  gets  out  of  the 
water.  In  the  second  case,  part 
of  the  water  goes  out  before  this ; 
but  the  air  rarefies,  and  therefore 
there  is  still  some  water  dragged 
or  lifted  up  by  the  wheel,  by  suc- 
tion, as  it  is  usually  called.  In  the 
last  case,  there  is  no  such  back- 
load  on  the  rising  side  of  the  Wheel, 
but  (which  is  as  detrimental  to  its 
performance)  the  descending  side 
is  employed  in  condensing  air ;  and 
although  this  ah*  aids  the  ascent  of 
the  rising  side,  it  does  not  aid  it  so 
much  as  it  impedes  the  descending 
side,  being  (by  the  form  of  the 
bucket)  nearer  to  the  vertical  line 
drawn  through  the  axis." 

These  were  the  difficulties  under 
which  the  millwrights  of  Dr.  Ro- 
bison's  time  laboured;  and  the 
remedy  which  they  applied  (and 
which  has  since  been  more  or  less 
continued)  was  to  bore  holes  in 
what  is  technically  caUed  the '  start* 
of  the  bucket.  This  was  the  only 
means  adopted  for  removing  the 
ah*  from  the  buckets  of  overshot 
wheels,  in  order  to  facilitate  the 
admission  and  emission  of  the 
water.  In  lower  falls,  where  wheels 
with  open  buckets  were  used,  or 
straight  fioat-boards  radiating'from 
the  centre,  large  openings  were 
made  in  the  sole-planking,  exclu- 
sive of  perforations  in  each  bucket, 
in  order  to  relieve  them  from  the 
condensed  air.  The  improved  con- 
struction of  the  present  time  is 
widely  different,  the  buckets  being 
of  such  a  shape  as  to  admit  the 
water  at  the  same  time  that  the  air 
is  making  its  escape. 

During  the  early  part  of  1825, 
and  the  two  succeeding^  years,  two 
iron  water-wheels,  each   of  one 


hundred  and  twenty  horse-power, 
were  constructed  in  Manchester 
for  Messrs.  James  Finlay  and  Co., 
of  the  Catrine  Works,  under  the 
auspices  of  the  late  Mr.  Buchanan, 
and  also  for  the  same  Company  at 
Deanston,  in  Perthshire,  of  which 
firm  Mr.  James  Smith  (Deanston) 
was  then  the  resident  partner. 
These  wheels  are  still  (1850)  in 
operation,  and  taking  them  in  the 
aggregate,  they  may  probably  be 
considered  as  some  of  the  most 
powerful  and  the  most  complete 
hydraulic  machined  in  the  United 
Kingdom.  The  construction  of 
these  wheels,  and  others  for  lower 
falls,  first  directed  attention  to  the 
ingress  and  egress  of  the  water,  and 
led  to  the  improvements  which 
have  since  been  introduced. 

The  object  of  these  modifications 
may  be  generally  stated  to  have 
been,  for  the  purpose  of  preventing 
the  condensation  of  the  air,  and 
for  permitting  its  escape,  during 
the  filling  of  the  bucket  with  wa- 
ter, as  also  its  re- admission  during 
the  discharge  of  the  water  into  the 
lower  mill-race. 

Shortly  after  the  construction  of 
the  water-wheels  for  the  Catrine 
and  Deanston  Works,  a  breast- 
wheel  was  made  and  erected  for 
Mr.  Andrew  Brown,  of  Linwood, 
near  Paisley.  In  this  it  was  ob- 
served, when  the  wheel  was  loaded, 
and  in  flood-waters,  that  each  of 
the  buckets  acted  as  a  water-blast, 
and  forced  the  water  and  spray  to 
a  height  of  six  or  eight  feet  above 
the  orifice  at  which  it  entered. 
This  was  complained  of  as  a  great 
defect,  and,  in  order  to  remedy  it, 
openings  were  cut  in  the  sole- 
plates,  and  small  interior  buckets 
were  attached  to  the  inner  sole,  as 
shown  at  d,  6,  d,  fig.  2.  The  air  in 
this  case  made  its  escape  through 
the  openings  a,  a,  a,  into  the  inner 
bucket,  and  passed  upwards,  as  is 
shown  by  the  arrows,  through  bfb,bf 
into  the  interior  of  the  wheel.  By 
these  means  it  will  be  observed 


525 


z5 


WAT 


WATER-WHEELS,  VENTILATED. 


WAT 


Kg.  a. 


that  the  backets  were  effectually 
cleared  of  air  whilst  they  were 
filling,  and  that  during  the  ob- 
structions of  back-water,  the  same 
facilities  were  afforded  for  its  re- 
admission,  and  the  discharge  of 
the  water  contained  in  the  rising 
buckets.  The  effect  produced  by 
this  alteration  could  scarcely  be 
credited,  as  the  wheel  not  only 
received  and  parted  with  the  water 
freely,  but  an  increase  of  nearly 
one-fourth  of  the  power  was  ob- 
tained, and  the  wheel,  which  still 
remains  as  then  altered,  continues, 
in  all  states  of  the  river,  to  per- 
form its  duty  satisfactorily. 

The  amount  of  power  gained, 
and  the  beneficial  effects  produced 
upon  Mr.  Brown's  wheel,  induced 
a  new  and  still  greater  improve- 
ment in  the  principle  of  construc- 
tion: the  first  wheel  erected  on 
this,  which  has  been  called  the 
*  ventilated'  prineiple,  was  one  de- 
signed for  Mr.  Duckworth,  at  the 
Handforth  Print-Works,  in  the 
neighboiurhood  of  Wihnslowy  in 
Cheshire. 

Close -bucketed  wheels  labour 
under  great  difiiculties  when  re- 
ceiving the  water  through  the 
same  orifice  at  which  the  air  es- 
capes,  and  in  some  wheels  the 

526 


forms  and  construction  of  the 
buckets  are  such  as  almost  entirely 
to  prevent  the  entrance  of  the  wa- 
ter, and  to  deprive  the  wheel  of 
half  its  power.  These  defects  may 
be  easily  accounted  for  where  the 
vrater  is  discharged  upon  the  wheel 
in  a  larger  section  than  the  openbg 
between  the  buckets:  under  such 
circumstances  the  air  is  suddenly 
condensed,  and,  re-acting  by  its 
elastic  force,  throws  back  the  wa- 
ter upon  the  orifice  of  the  cistern, 
and  thus  allows  the  buckets  to 
pass  vrithout  their  being  more  than 
half-filled.  Several  methods  have 
been  adopted  for  relieving  them  of 
the  air :  the  most  common  plan  is, 
by  cutting  holes  in  the  sole-plates, 
close  to  the  back  of  the  buckets, 
or  else  making  ihe  openings  be- 
tween them  much  wider,  in  order 
to  admit  the  water,  and  at  the 
same  time  to  allow  the  air  to  es- 
cape. All  these  remedies  have 
been  more  or  less  effective;  hot 
they  labour  under  the  objections 
of  a  great  waste  of  water  and  mudi 
inconvenience,  by  the  water  falling 
from  the  openings  down  upon  the 
lower  part  of  the  wheel,  exclusive 
of  the  puffing  and  blowing  when 
the  bucket  is  filling. 

Other  remedies  have  been  ap- 
plied, such  as  drcukr  tubes  and 
boxes  attached  to  the  aole-plates, 
which,  extending  upwards,  fnrmsh 
openings  into  the  interior  €ji  the 
wheel  for  the  air  to  escape;  but 
these,  like  many  other  plana,  have 
been,  to  a  certain  extent,  unsuccess- 
ful, owing  to  the  complexity  of 
their  structure,  and  the  inadequate 
manner  in  which  the  ohjecta  con- 
templated were  attained.  In  fact, 
in  wheels  of  this  description  it  has 
been  found  more  aatisfactory  to  sub- 
mit to  acknowledged  defects,  thsn 
to  incur  the  trouble  and  inconve- 
nience of  partial  and  impeifBct 
remedies. 

In  the  improvements  made  by 
•Mr.  Fairbaim,  these  objections  are 
to  a  great  extent  removed,  and  a 


WAT 


WATER-WHEELS,  VENTILATED. 


WAT 


thorough  system  of  ventilation  has 
been  effectaally  introduced.  Be- 
fore entering  upon  the  description 
of  this  new  principle  of  ventilation, 
it  is  necessary  to  remark,  that  in 
climates  fike  Great  Britain  and  Ire- 
land, where  the  atmosphere  is 
charged  with  moisture  for  six  or 
seven  months  in  the  year,  it  is  no 
uncommon  occurrence  for  the 
rivers  to  be  considerably  swollen, 
and  the  mills  depending  upon  wa- 
ter are  either  impeded  or  entirely 
stopped  by  back-water;  while  at 
other  times  a  deficiency  of  rain  re- 
duces the  water-power  below  what 
is  absolutely  required  to  drive  the 
machinery.  On  occasions  of  this 
kind,  much  loss  and  inconvenience 
are  sustained,  particularly  in  mills 
exclusively  dependent  upon  water 
as  a  motive  power,  and  where  a 
number  of  work-people  are  em- 
ployed. 

On  the  outskirts  of  the  manu- 
facturing districts,  where  the  mills 
are  more  or  less  dependent  upon 
water,  these  inconyeniences  are  se- 
verely felt ;  and  in  some  situations 
these  interruptions  arise  as  fre- 
quently from  an  excess  of  water  as 
ih>m  a  deficiency  in  the  supply. 
To  remedy  these  evils,  reservoirs 
have  been  formed,  and  wheels  have 
been  constructed  to  work  in  floods ; 
but  although  much  has  been  ac- 
complished for  diminishing  these 
injurious  effects,  and  giving  a  more 
regular  supply  in  dry  seasons,  yet 
the  system  is  still  imperfect,  dnd 
much  has  yet  to  be  done,  before 
water  can  be  considered  equal,  as  a 
motive  power,  to  the  steam  engine, 
which  is  always  available  where 
the  necessary  ftiel  is  at  hand.  It  is 
therefore  obvious,  that  any  im- 
provement in  the  construction  of 
water-wheels,  whereby  their  forms 
and  requirements  may  be  better 
adapted  to  meet  the  exigencies  of 
high  and  low  waters,  vrill  contri- 
bute much  to  the  efficiency  and 
value  of  mills  situated  upon  rivers 
subjected  to  the  changes  alluded  to. 

527 


WateV'WheeU {Ventilated^  tu  adapted 
to  UfwfaUt, — The  first  wheel  con- 
structed upon  the  ventilated  prin- 
ciple was  erected  at  Handforth,  in 
Cheshire,  in  the  summer  of  1828  : 
it  proved  highly  satisfactory  to  the 
proprietors,  Messrs.  Duckworth  and 
Co.,  and  gave  such  important  re- 
sults as  to  induce  its  repetition, 
vrithout  variation,  in  cases  where 
the  fall  did  not  exceed  the  semi- 
diameter  of  the  wheel. 

In  the  earlier  construction  of 
iron  suspension  wheels  by  the  late 
Mr.  J.  C.  Hewes,  the  arms  and 
braces  were  fixed  to  the  centres  by 
screws  and  nuts  upon  their  ends, 
as  shown  in  fig.  3.  The  arms  c,  c, 
passed  through  the  rim  6,  &,  and 

Fig.  3. 


the  braces  e,  e,  which  traverse  the 
angle  of  the  rim/,/,  are,  as  nearly 
as  possible,  in  the  position  and 


■ 


WAT 


WATER-WHEELS,  BREAST. 


WAT 


form  adopted  by  Mr.  Hewes.  This 
arrangement,  although  convenient 
for  tightening  up  the  arms  and 
braces,  was  hable  to  many  objec- 
tions, arising  from  the  nats  be- 
coming loose,  and  the  consequent 
difficulty  of  keeping  the  wheels 
true  to  the  circle,  and  the  arms 
and  braces  in  an  uniform  state  of 
tension:  gibs  and  cotters  were 
therefore  substituted  for  the  nuts 
and  screws,  and  since  their  intro- 
duction into  the  large  wheels  of 
the  Catrine  Works,  Ayrshire,  the 
objections  have  been  removed,  and 
the  arms  and  braces  are  not  only 
perfectly  secured,  but  the  peri- 
phery of  the  wheel  is  retained  in 
its  true  and  correct  form. 

Having  noticed  the  obstructions 
offered  to  the  entrance  of  the  wa- 
ter into  buckets  of  the  usual  form, 
and  the  consequent  loss  which  en- 
sues from  its  retention  upon  the 
wheel,  after  its  powers  of  gravita- 
tion have  ceased,  it  is  now  neces- 
sary to  show  the  means  whereby 
those  defects  were  removed,  and 
also  to  exhibit  the  relation  existing 
between  the  breast  and  the  under- 
shot wheels.  These  terms  have, 
however,  become  nearly  obsolete, 
as  every  description  of  water-wheel 
may  now  be  properly  called  a 
breast-wheel;  and  in  every  fall, 
however  low,  it  is  generally  found 
advantageous  for  the  water  to  act 
by  gravitation,  and  not  by  impulse, 
as  during  the  early  periods  of  the 
industriid  arts. 
WateT'Wheelt  {Breast),  with  close 
Soles  and  ventilated  Buckets,  The 
preceding  statements  have  been 
principally  confined  to  the  form  of 
bucket,  and  description  of  water- 
wheel,  adapted  for  low  falls.  It 
is  therefore  necessary  to  describe 
the  best  form  of  breast-wheels  for 
high  falls,  or  those  best  calculated 
for  attaining  a  maximum  effect  on 
falls  varying  from  one-half  to  three- 
fourths  of  the  diameter  of  the 
wheeL  This  is  a  description  of 
water-wheel  in  common  use,  and 

528 


is  generally  adopted  fcN'  faXh 
which  do  not  exceed  18  feet  in 
height,  and,  in  most  cases,  is  pre- 
ferable to  the  overshot  wheeL  It 
possesses  many  advantages  over  the 
undershot  wheel,  and  its  near  ap- 
proximation to  the  dnty,  or  labour- 
ing force,  of  wheels  of  the  former 
description,  renders  it  applicable  in 
many  situations,  espe<daUy  where 
the  fall  does  not  exceed  18  or  20 
feet,  and  where  the  wheel  is  ex- 
posed to  the  obstructions  of  back- 
water. In  the  latter  case,  wheels 
of  larger  diameter  are  best  adapted; 
and  provided  sufficient  capacity  is 
left  in  the  buckets,  such  wheek 
may  be  forced  through  the  back- 
water without  diminution  of  speed. 
Every  wheel  of  this  kind  should 
have  capacity  in  the  buckets  to  re- 
ceive a  sufficient  quantity  of  water 
to  force  the  wheel,  at  fiiU  speed, 
through  a  depth  of  5  or  8  feet  ci 
back-water;  and  if  these  provisions 
are  made,  a  steady  uniform  speed, 
under  every  circumstance  of  freshes 
and  flood-waters,  may  be  attained. 

Irrespective  of  the  advantages 
of  clearing  the  buckets  oi  air,  aid- 
diti<mal  benefit  is  obtained  by  the 
fiacility  with  which  the  water  is 
discharged,  and  the  air  i^ain  ad- 
mitted, at  the  bottom  of  the  fidi, 
during  the  period  of  the  emptying 
of  the  bucket  into  the  tail-race. 
This  is  strikingly  illustrated  where 
the  wheels  labour  in  back-water, 
as  the  ventilated  buckets  rise  freely 
alwve  the  surface,  and  the  comma- 
nication  being  open  from  one  to 
the  other,  the  action  is  rendered 
perfectly  free,  at  almost  any  depth 
to  whidi  the  wheel  may  be  im- 
mersed. 

In  breast-wheels  oonstmcted  for 
falls  of  25  feet  or  upwards,  the 
stone-breast  is  not  required,  as  the 
buckets  are  formed  with  narrow 
openings,  and  the  lip  being  ex- 
tended nearer  to  the  back  of  the 
following  bucket,  the  water  is  re- 
tained much  longer  upon  the  wheel 
Under  these  circumstances,  a  stone- 


WAT 


WATER-WHEELS. 


WAT 


breast  is  of  little  or  no  value,  when 
attached  to  a  wheel  with  close 
buckets,  on  a  high  fall. 

The  construction  of  the  breast-   I 
wheels,  as  above  described,  is  al- 
most exactly  similar  to  that  for  the 
lower  falls;  malleable  iron   arms 
and  braces  being  common  to  both, 
as  also  the  axle,  shroud,  and  seg- 
ments.    These,  when   duly  pro- 
portioned and  properly  fitted  to 
each  other,  form  one  of  the  strong- 
est, and  probably  the  most  per- 
manent structures,  that  can  be  at- 
tained in  works  of  this  description. 
Water-wheel  {common  Breast^  not 
ventilated),     as     constructed    hy 
Messrs.  Fairhaim  and  LiUie,  be- 
tween the  years  1825  and  1827. 
These  wheels  were  executed  upon 
the  plan  of  the  overshot  or  breast- 
wheel,  taking  the  water  at  an  ele-  , 
vation  nearly  equal  to  that  of  its 
height.    Four  wheels  of  this  de- 
scription   were    constructed    for 
Messrs.  James  Finlay  and  Co.,  for 
a  fall  of  32  feet,  at  Deanston,  in 
Perthshire,  and  two  others,  for  the 
same  firm,  at  the  Catrine  Works, 
in  Ayrshire,  on  a  fall  of  48  feet. 
Takinginto  consideration  the  height 
of  the  fall,  the  Catrine  water-wheels, 
hoth  as  regards  their  power  and 
the  solidity  of  their  construction, 
are,  even  at  the  present  day,  pro- 
bably among  the  best  and  most 
effective  structures  of  their  kind  in 
existence.    They  have  now  (1850) 
been  at  work  upwards  of  twenty 
years,  during  which  time  they  have 
required  no  repairs,  and  they  remain 
nearly  as  perfect  as  when  they  were 
erected. 

It  was  origihally  intended  to 
have  erected  four  of  these  wheels 
at  the  Catrine  Works,  but  only  two 
have  been  constructed;  prepara- 
tions were,  however,  made  for  re- 
ceiving two  others,  in  the  event  of 
an  enlargement  of  the  reservoirs  in 
the  hilly  districts,  and  more  power 
being  required  for  the  mills.  This 
extension  has  not  yet  been  wanted, 
as  these  two  wheels  are  equal  to 

529 


240  horse-power,  and  are  suffi- 
ciently powerful,  except  in  very 
dry  seasons,  to  turn  the  whole  of 
the  mills. 

These  water-wheels  are  50  feet  in 
diameter,  lOfeeteinches  wide  inside 
the  bucket,  and  15  inches  deep  on 
the  shroud ;  the  internal  spur  setr- 
ments  are  48  feet  6  inches  diametw 
H  inches  pitch,  and   15  inches 
broad  on  the  cog ;  the  large  spur- 
wheels   are   18  feet  2^  inches  in 
ojameter,  3^  inches  in  the  pitch, 
and  16  inches  wide  on  the  cog' 
and  the  pinions  are  the  same  width 
and  pitch,  but  are  5  feet  6  inches 
in  diameter ;  the  large  bevel-wheels 
are  7  feet  in  diameter,  3^  inches  in 
the  pitch,  and  18  inches  broad  on 
the  cog,  their  proportions  being 
calculated  to  convey  the  united 
power  of  all  the  four  water-wheels, 
should  the  original  design  ever  be 
completed. 

The  water  for  the  supply  of  the 
wheels  is  conveyed  from  the  river 
Ayr  in  a  canal  and  tunnel,  and 
from  thence,  along  the  side  of  a 
rising  bank,  to  the  wheel-house. 
From  this  point  it  is  conveyed  to 
the  water-wheels  by  a  large  sheet- 
iron  trough,  supported  on  iron  I 
columns. 

When  viewed  from  the  entrance, 
the  two  wheels  already  erected  have 
a  very  imposing  effect,  each  of  them 
being  elevated  upon  stone  piers; 
and  as  the  whole  of  the  cisterns, 
sluices,  winding  apparatus,  gal- 
leries, &c.,  are  considerably  ele- 
vated, they  are  conveniently  ap- 
proached in  every  part.  Under 
the  wheels  is  a  capacious  tunnel, 
terminating  at  a  considerable  dis- 
tance down  the  river. 

Water-wheels  on  a  prindple  in- 
troduced by  M.  Poncelet,  have  at- 
tained some  considerable  reputa- 
tion on  the  Continent ;  and  as  Mr. 
rairbaim  has  constructed  one  of 
them  for  Mr.  De  Bergue,  it  is  ne- 
cessary to  allude  briefly  to  the  pe- 
culiarities it  possesses. 

The  buckets  are  of  a  curvilinear 


WAT 


WATER-WHEELS. 


WAT 


form,  and  are  quite  open  at  the 
back,  without  any  sole-plate;  so 
that  they  are  perfectly  ventilated. 
The  water  impinges  upon  them  at 
nearly  the  lowest  point  of  the 
wheel,  the  shuttle  being  arranged 
to  draw  upwards ;  and  as  the  wa- 
ter enters,  it  follows  the  inside  ca- 
vity of  the  bucket,  rises  and  falls 
over  into  the  next  in  succession, 
and  so  on.  By  this  system  the 
force  of  the  water  is  expended  on 
the  wheel  itself,  instead  of  losing 
much  of  its  power  in  rushing  along 
through  the  wheel-race,  as  ge- 
nerally occurs  in  even  well-made 
undershot  wheels. 

M.  Poncelet  has  treated  this 
subject  at  much  length  in  his  able 
work  on  water-wheels ;  but  it  may 
be  observed,  that  a  practical  im- 
provement might  be  effected  by  ter- 
minating the  lower  stone  platform 
of  the  race  somewhat  short  of  the 
vertical  line  of  the  centre  of  the 
wheel,  as  the  escape  of  the  water 
would  be  facilitat-ed,  and  the  as- 
cending buckets  would  be  more 
easily  relieved  of  their  contents: 
this  is  a  point  of  such  importance 
for  all  wheels,  that  it  must  equally 
apply  to  this  form. 

Mr.  De  Bergue  obtained  nearly 
seventy-eight  per  cent,  of  power 
from  a  breast-wheel,  with  a  good 
fall,  when  the  periphery  was  travel- 
ling at  avelocity  of  6  feet  per  second. 

He  had  erected  several  of  Ponce- 
let's  wheels,  and  thought  well  of 
them;  indeed,  for  certain  situa- 
tions it  was  thought  they  were  pre- 
ferable to  any  other  form,  although 
M.  Poncelet  had  never  yet  been 
able  to  obtain  very  superior  results 
from  wheels  erected  under  his  own 
superintendence. 

Mr.  De  Bergue  has  explained  the 
construction  of  a  wheel,  on  this 
principle,  erected  at  the  Loubre- 
gat,  near  Montserrat,  in  Catalonia ; 
one  of  the  same  kind  having  been 
already  erected  by  him  at  Gerona, 
between  Barcelona  and  Belgrade. 

The  diameter  was   16  feet  8 

530 


inches,  and  the  width  was  30  feet, 
which,  with  a  fall  of  6  feet  6 
inches,  passed  120,000  cubic  feet 
of  water  per  minute,  when  the 
periphery  travelled  at  a  velocity  of 
11  to  12  feet  per  second.  An  or- 
dinary breast-wheel  would  reqoiit 
to  be  90  feet  wide,  to  use  advan- 
tageously  that  quantity  of  water. 
It  was  found  that  the  velocity  of 
the  periphery  should  be  about  55 
per  cent,  of  that  of  the  water  flow- 
ing through  the  sluice ;  and  upon 
these  data  the  power  of  the  wheel 
would  be  about  180  horse-power.  : 
The  buckets  were  of  a  curredl 
form,  and  made  of  wrought  iron, 
l^th  of  an  inch  thick ;  and  it  should ; 
be  observed  that  there  was  a  larger : 
number  of  buckets  than  usual,  and 
that  the  water  came  upon  them  at  [ 
a  tangent,  through  an  orifice  of 
such  a  form  and  dimensions  as  to 
allow  the  buckets  to  fill  easily,  at 
the  rapid  speed  at  which  the  peri- 
phery passed  before  the  sluice. 
This  great  primary  velocity  was 
very  important,  as  it  caused  a  con- 
siderable saving  in  the  gearing  of 
the  mill. 

The  main  shaft  was  formed  by 
a  hollow  cylinder  of  cast  iron,  4 
feet  6  inches  diameter,  in  short 
lengths,  bolted  together;  and  the 
arms  were  of  wrought  iron,  made 
very  light,  and  of  the  same  form  | 
as  those  of  a  paddle-wheel  of  a  j 
steamer,  and  placed  very  close  to- 
gether. The  strain  was  brought 
entirely  upon  the  main  shaft,  and 
the  weight  of  the  wheel  was  thus 
reduced  to  about  thirty  tons,  which 
was  very  little  for  so  powerful  a 
machine. 

The  sluice  was  formed  of  cast- 
iron  plates,  with  planed  joints, 
bolted  through  the  flanches,  to 
form  one  large  shuttle  of  the  en- 
tire breadth  of  the  wheel,  and  its 
motion  was  regulated  by  radial  tie- 
rods,  between  the  stone  apron  and 
the  back  of  the  sluice,  which  could 
thus  be  raised  with  great  facility 
by  racks  and  pinions,  and  be  regu- 


WAV 


WEIGHTS  AND  MEASURES. 


WEI 


lated  by  the  ordinary  governor,  the 
weight  of  the  sluice  being  in  a 
great'  degree  supported  by  the 
water  flowing  beneath  it  on  to  the 
wheel.  It  moved  very  accurately 
between  the  side  walls  of  the  pen- 
trough,  and  cup-leathers  at  each 
side  prevented  any  waste  of  water. 
This  kind  of  wheel  was  less  af- 

■  fected  by  back-water  than  any 
other  form,  and  the  water  acted 
upon  it  with  its  full  power  of  ve- 
locity, without  any  impediment 
from  the  air  in  entering,  as  there 
was  no  sole-plate  :  the  buckets 
filled  and  emptied  with  great  fa- 
cility. It  is  therefore,  most  satis- 
factory for  all  falls  under  8  feet  in 
height,  though  the  principle  dif- 
fers essentially  from  that  generally 
taken  as  the  basis  of  construction 
of  water-wheels. 

Wavedf  in  heraldry,  an  indented  out- 
line, indicating  honours  originally 
acquired  at  sea 

Wayshqftf  in  steam  engines,  the 
rocking-shaft  for  working  the  slide- 
valve  from  the  eccentric 

Wax,  the  substance  of  which  the 
honey-combs  of  bees  are  composed, 
and  which  is  of  considerable  use  in 
branches  of  art 

Weathercock,  a  vane  made  in  the 
shape  of  a  cock 

Weather-gage,  in  navigation.  When  a 
ship  is  to  windward  of  another,  she 
is  said  to  have  the  weather-gage 
of  her. 

Weather-gkm,  an  instrument  to  fore- 
show the  change  of  weather  and 
the  temperature  of  the  air 

Weather-moulding,  a  label,  canopy,  or 
drip-stone,  over  a  door  or  window, 
intended  to  keep  off  water  from 
the  parts  beneath 

Wedge,  The  wedge  is  a  solid  piece 
of  wood  or  metal,  generally  made 
in  form  of  a  triangle  prism,  of 
which  the  two  ends  or  bases  are 
equal  and  similar  plane  triangles, 
and  the  three  sides  rectangular 
parallelograms ;  and  it  is  called 
rectangular,  isosceles,  or  scalene, 
according  as  its  equal  and  similar 

W2      ~" 


bases  are  composed  of  right  angles, 
isosceles,  or  scalene  triangles.  As 
a  mechanical  power,  the  wedge 
performs  its  office,  sometimes  in 
raising  heavy  bodies,  bat  more  fre- 
quently in  dividing  or  cleaving 
them ;  hence  all  those  instruments 
which  are  used  in  separating  the 
parts  of  bodies,  such  as  axes,  adzes, 
knives,  swords,  coulters,  chisels, 
planes,  saws,  files,  nails,  spades, 
&c.,  are  only  different  modifica- 
tions that  fall  under  the  general 
denomination  of  the  wedge. 

Weighboard,  in  mining,  day  inter- 
secting a  vein 

Weight  and  power,  when  opposed  to 
one  another,  signify  the  body  to 
be  moved  and  the  body  that  moves 
it.  That  body  which  conmiani- 
cates  the  motion  is  called  the 
power,  and  that  which  receives  it 
the  weight. 

Weights  and  MeaaureB,  The  system ; 
of  weights  and  measnres  used  in 
France  at  present,  in  all  legal  trans- 
actions, is  called  the  'metrical 
system,'  from  the  fact  of  its  being 
based  upon  the  unity  of  length, 
which  is  designated  '  the  metre.' 

Before  the  great   revolution  of 
1793,  the  separate  provinces  of  the 
French  kingdom  had  their  different 
systems  of  measures;    just  as  in 
England  the  different  counties  had  j 
theirs,  before  the  introduction  of 
the  imperial  measures.    There  was, 
consequently,  the  same  confusion , 
attached  to  the  meanings  of  the  i 
different  terms  employed,  which  i 
led  our  own  Government  to  sim-  < 
plify  the  question.      An  acre  in , 
Normandy  did  not  mean  the  same 
as  an  acre  in  Picardy ;  a  pound  in 
Paris  diffiered  from  a  pound  else- 
where.    But  here  the  analogy  be- , 
tween  the  conduct   of   the  two 
Governments     ceases.      That   of 
France  reformed  the  whole  system 
of  weights  and  measures,  and  based 
the  new  one  upon  natural  and  easily 
verifiable  principles, — whilst  our 
own  retained  the  arbitrary  and  illo- 
gical system  of  the  middle  ages, 


WEI 


WEIGHTS  AND  MEASURES. 


WEI 


conteDting  themselyes  with  merely 
fixing  a  sort  of  uniformity  in  the 
definitions  of  the  several  terms. 

The  merit  of  having  originated 
the  metrical  system  is  due  to  the 
government  of  Louis  XV.,  who 
named  a  commission  to  pursue  the 
investigations  necessary  to  decide 
the  principles  upon  which  it  was  to 
be  carried  out.  After  a  very  se- 
rious consideration  of  the  case,  and 
a  numerous  series  of  observations 
carried  on  during  the  reign  of 
Louis  XYI.,  and  under  the  Con- 
vention, the  Academy  of  Sciences 
decided  that  all  the  different 
weights,  measures,  and  coinages 
should  be  established  according  to 
certain  definite  relations  to  the  di- 
mensions of  the  globe  itself.  These 
are,  to  all  human  perception,  inva- 
riable. If  therefore  the  standard 
were  lost,  it  is  always  possible  to 
refind  it,  by  a  repetition  of  the  sune 
sort  of  observations  which  gave  rise 
to  the  fixing  it  in  the  first  instance. 
The  beat  of  a  pendulum,  chosen  by 
our  own  Astronomical  Board,  is  a 
very  uncertain  base  for  such  calcu- 
lations; for  the  conditions  of  the 
vacuum,  the  temperature  of  the 
atmosphere,  the  specific  gravity  of 
the  pendulum,  nay,  perhaps,  even 
the  magnetic  currents,  may  affect 
the  length  of  the  space  it  goes 
through,  in  a  manner  able  to  affect 
calculations  which  require  such  ma- 
thematical exactitude  as  those  con- 
nected with  ascertaining  the  stand- 
ard of  a  perfect  system  of  measures. 

The  length  of  the  earth's  meri- 
dian was  ascertained  by  Messrs. 
Delambre  and  Mechain,  in  the  por- 
tion  between  Dunkerque  and  Bar- 
celona ;  and  by  Messrs.  Arago  and 
Biot,  in  the  portion  between  Bar- 
celona and  Formentera.  The  length 
of  the  meridian  from  the  pole  to  the 
equator,  passing  through  Paris,  was 
then  divided  into  ten  million  parts ; 
and  one  of  these  parts,  called  the 
metre,  became  the  basis  of  the  new 
system  of  weights  and  measures. 
Maupertuis  had  previously,  in  the 


year  1736,  measured  a  portion  of 
the  arc  of  a  meridian  passing 
through  the  North  Cape,  and  his 
observations  were  combined  with 
those  of  the  second  commission. 
In  spite  of  all  this  cafce,  however, 
an  error  was  made  in  fixing  the 
length  of  the  metre ;  for  the  dis- 
tance from  the  equator  to  the  pole 
is  really  10,000,738  metres,  instead 
of  10,000,000.  For  any  practical 
purpose,  however,  this  error  is 
inapplicable;  but  it  is  very  unfor- 
tunate. 

The  length  of  the  m^tre  once  as- 
certained, the  other  measures  were 
derived  from  it.  All  the  multiples 
and  sub-multiples  were  formed  on 
the  decimal  system,  and  respec- 
tively designated  by  Greek  and 
Latin  prefixes  to  the  name  of  the 
unities.  Thus,  the  multiples  of  the 
metre  are  the  deea'tnetTet  ten  me- 
tres ;  the  heeto-metret  a  hundred 
metres ;  the  ^'fo-metre,  a  thousand 
metres;  the  myrta-metre,  ten  thou- 
sand metres.  In  deference  to  old 
customs  the  term  'league'  has 
been  retained,  and  a  legid  value  of 
four  kilometres  afiixed  to  it. 

The  sub-multiples  of  the  metre 
are :  the  <fect-metre,  the  tenth  part 
of  a  m^tre ;  the  cen/»-metre,  the 
hundredth  part  of  a  metre ;  and  the 
mtV/t-metre,  the  thousandth  part  of 
a  metre. 

The  same  prefixes  are,  of  course, 
applicable  to  all  the  other  unities. 

The  unities  of  length  in  use  for 
ascertaining  the  distances  of  places, 
are,  as  said  before,,  the  metre  (the 
kilometre  and  the  myriam^re)  and 
the  league* 

The  unity  of  surface  is  the  *  are,* 
which  is  a  square  of  ten  metres  on 
a  side,  or  one  hundred  superficial 
metres.  The  usual  multiples  and  \ 
sub-multiples  are,  the  Aec^-are,  a  \ 
square  of  one  hundred  metres  on  a 
side ;  and  the  cm^t-are,  the  metre 
superficial.  The  terms  usually  em- 
ployed in  the  sale  of  land  and  in 
agricultural  discussions  are^  simply, 
those  named  above. 


533 


WEI 


WEIGHTS  AND  MEASURES. 


^t: 


The  unity  of  weight  is  the 
'  gramme/  which  is  the  equivalent 
of  a  cuhe  of  distilled  water  (at  a 
temperature  of  4®  above  the  *  ice- 
melting  point'  of  the  centigrade 
scale), measuring  a  centimetre  every 
way.  The  multiples  and  sub-mul- 
tiples are,  as  before:  the  deca- 
gramme, ten  grammes ;  the  hecto- 
gramme, a  hundred  grammes ;  the 
kilogramme,  a  thousand  grammes ; 
the  decigramme,  a  tenth  part  of 
a  gramme,  &c.  A  thousand  kilo- 
grammes, then,  would  form  a 
cube  equal  to  one  measuring  a 
metre  on  every  side;  and  it  is 
made  the  legal  ton  for  heavy 
weights. 

The  unity  of  capacity  is  the 
'litre,'  which  is  the  equivalent  of  a 
cube  measuring  one-tenth  pBrt  of 
a  metre,  or  a  decimetre,  every  way. 
The  multiples  and  sub-multiples 
are  formed  as  before.  They  are, 
the  decalitre,  the  hectolitre,  the 
kilolitre,  the  decilitre,  and  the 
centilitre,  &c.  The  litre  is  usually 
employed  in  expressing  the  quan- 
tities of  liquids ;  the  hectoUtre  in 
expressing  those  of  grain* 

A  thousand  litres  of  water  thus 
are  equal  to  a  metre  cube  every 
way,  and  are  one  ton  in  weight. 
Another  advantage  in  this  system 


is,  that  the  tables  of  specific  gr&^nn 
serve  at  once  to  ascertain  thr 
weights  of  the  different  substances.! 
Thus,  inasmuch  as  the  spedfic 
gravity  of  cast  iron  is  7202,  the 
weight  of  a  metre  cube  is  at  ooct 
7202  kilogrammes,  or  7  tons  202 
kilogrammes. 

The  *  franc'  the  unity  of  the 
French  coinage,  is  5  grammes  in 
weight  of  an  alloy  containing  nine 
parts  of  pure  silver  to  one  of  allof, 
being  thus  connected  vrith  the 
whole  metrical  and  decimal  system. 

As  investigations  connected  with 
the  supply  of  water  are  of  great 
importance,  it  may  be  added,  that 
the  quantity  reckoned  as  the  umtjii 
such  calculations  is  the  module  or 
20  cubic  metres ;  being  nearly  the 
equivalent  of  the  old  *  ponce  /bo- 
tanier,'  or  the  quantity  usually  de- 
livered by  a  hole  of  one  inch  dia- 
meter in  the  24  hours. 

The  law  promulgating  the  me- 
trical system  was  dated  in  the  year 
1795.  The  forced  application  of 
it  in  legal  transactions  did  not  take 
place  till  nearly  50  yean  after- 
wards. 

A  Table  is  subjoined  of  the  dif- 
ferent French  weights  and  mea- 
sures, with  the  corresponding  ^^• 
lish  equivalents. 


\ 


Weights  and  Meaauret-^French^  with  their  English  egmvaientt, 
FsaircH.  WEIGHT.  English. 

«*"»•  •  •  .  •  {'s^i':':?dr'!^'^''*}«»-««p^t"7 

f  a  thougand  grammes,  or  a  cube "]  q.aqaqa  n..  »««« 

Kilogninine        •       •       •    -^     of'^t?; <>»«-*«»*»> <>f»«»^*"  ^ISSSftL'i^Upai 

^    on  a  tide      ....  J 

EiffOLxSH  TaoT.  RxciPBOCALLT.  Fkbncb. 

Grain equal  to 0*06477  gramme 

Pemiyweight       ...         „  1*55456        „ 

Ounce .....         „  31*0013  Rrammet 

Pound  Troy  (Imperial)       .         ,»  0*8730750  kilognmme 

AVOIBOUPOIS. 

Drachm       ....    equal  to 1*7713  gnramme 

Ounce ,,  38-3384  grammes 

Pound ,,  0*4534148  kilognfflBie 

Hundred-weigfat  •       .       .         „  50*7896  kUogramiDet 

Ton 1016*640  „ 

534 


WEI 


WEIGHTS,  COMPARATIVE. 


WEI 


To  convert  pound,  avoirdupoi.  into  kilogrammes,  or  English  ton.  into  French  ton., 

or  vice  versA,  multiply  or  divide  a.  foUow. :  * 

PoJLThJ^^ 0-4634148 

For  ton.  by 1-015649 


Frxncb. 


ElfOLISH. 


LENGTH. 

fabout  40,000,000th  part  of  cir-'l 
M&tre J     cumference  of  the  globe,  or  I  3-2808903  feet 

I     lO-millionth  part  (tf  a  quarter  f  1*093633  yard 
-«..        ^.  L     of  do.  I  '       * 


Kilometre  . 
Myriam^tre  . 
Centiinto«  . 
MillimHre   . 


The  inch 
9,     foot 


English. 


99 


„     yard 
„     furlong , 
xnile 


« 


L    of  do. 

one  thouuind  mdtre.  . 
ten  thousand  metres   .        . 
one-hundredth  of  a  mitre  . 
one-thousandth  <^  a  mitre  . 

RXCIPKOCALLT. 

one-twelfth  of  a  foot  English 


1093*633  yard. 
10936*33  yard. 
0*393708  inch 
0*0393708  inch 

Fkbnch. 

3*539954  centimetre. 
3*0479449  decimetre. 
0*91438348  mitre 


•  ?/**'  •  , 0*91438348  mitre 

•  ffi,^"*T 301*16437  mitres 

•  1/Wyard. 1609*3149  mitre. 

TO  reduce  Engli.h  measures  into  FVench,  multiply  by ;  and  to  reduce  French  measure. 
T«^»  — ♦         ^    V  wto  English,  divide  by: 

Inches  to  centimitre.  ,       .    3*64oo 

Mil^to'k^itri      :       :    J:gjJ7946-practicaUy  0*3048 

Feet  square  to  mitre,  .quare  0*09290 

>,    cube  to  mitre,  cube     ,    0*028314      ,  /  ^  T*"!  d^  equals 

*     \      0*76458  mitre  cube 


Centiare 
Are 

Hectare 


Fbbmch. 


SURFACE.  English. 

a  mitre  superficial  .       .  1-196033  yards  niperfidal 

a  square  of  10   mitres  every  side  0*098845  rood 

100      ..  2*471 143  acres 


»» 


*» 


»> 


A  jrard  square 
The  rod,  or  . 

rood     , 

acre 


RSCIPBOCALLT. 

•       .  contains      .....  0*88697  mitre  M^uare 

.  perch  square       ....  25*291939  mitre,  wjuaie 

.  1210  yard,  square        .        .       .  10*  116775  ares 

•       •       •       .  4840    do.     do.           ...  0*404671  hectare 

In  round  numbers,  the  hectare  may  be  taken  as  equal  to  2^  acres. 


Frxnch. 


ENGI'ISH* 


CAPACITY.  Ajiui.»<i 

^'tw /»c"^  of  one-tenth  of  a  mitre  \  1-760773  pint 

?-^^   ....  teniiS^*."^.*'    •     •     •     -^ai^S^gS^eS!!! 


Decalitre 
HectoUtre 


ten  litres 

one  hundred  litres 


2-2009668  gallon. 
2S-009668      If 


English. 

Pint     . 
Quart  . 

Gallon  Imperial   . 
Chaldron 


equal  to 

9f 
9$ 

99 


Bhcipbocallt. 


Fbbnch. 

.  ©•667932  litre 

.  1*135864     » 

.  4*54345794  litre. 

rj,  "-....  13*08516  hectolitre. 

b^oK!i?^*?±P^"°*^J*?  ;°^^  superficial  into  their  equivalent,  calculated 
u  aiogramme.  per  centimitre  superficial,  or  vice  vcrsA,  multiply,  orcUvidc,  by  0*0702774. 

Weiffhf  mpounds  of  one  eudicfoot  of  the /bOotaing  9u6stanee8: 

Castiron     ....  450-  M^ater 62-5 

Wrought  iron.    .    .  486-  Air  ...          .  0-075 

Steel.    .....  489-  Steam 0-036 

Pine  wood  .    .    .    ,  29*5  cwa  .     .     .     .  u  vow 


535 


WEI 


WEIGHT  OF  IRON. 


WEI 


Weight  qfa  Superficial  Foot  of  Plat 

e  or  Sheet  Iron. 

No.  ofth* 

ThickneM 

Weight  in 

No.  of  the 

Thicknen 

Wdgbt  in 

wire-gauge. 

in  inches. 

pounds. 

wire-gauge. 

in  inches. 

pounds. 

1 

40- 

12 

4-38 

i 

35- 

13 

3-75 

f 

30- 

14 

3-12 

H 

27-5 

15 

2*82 

t 

25- 

16 

A 

2-50 

■h 

22-5 

17 

218 

i 

20- 

18 

1*86 

iV 

17-5 

19 

1-70 

f 

15- 

20 

1-54 

1 

^ 

12-5 

21 

1-40 

2 

12- 

22 

^ 

1-25 

3 

11- 

23 

112 

4 

i 

10- 

24 

1- 

5 

8-74 

25 

0-9 

6 

812 

26 

0-8 

7 

A 

7-5 

27 

0-72 

8 

6-86 

28 

*f 

0*64 

9 

6-24 

29 

0*56 

10 

5-62 

30 

0-50 

11 

i 

•     5- 

Weight  of  Rod  Iron  Ifoot  in  lengthy  of  the  JbUowing  Dtmenaiom, 


SaUARE  IRON. 

ROUND  IRON. 

FLAT 

IRON. 

Inch. 

Pounds. 

Inch. 

Pounds. 

Inch. 

Pounds. 

i 

0-2 

i 

014 

*xl 

0-8 

t 

0-5 

i 

0-4 

f     1 

1-3 

i 

0*8 

i 

0-7 

1-7 

a 

1-8 

1 

1- 

21 

f 

1-9 

» 

1-5 

2-5 

i 

2-6 

i 

2- 

i    2 

1-7 

1 

3-4 

2-7 

t    2 

2-5 

H 

4-3 

U 

3-4 

f    2 

.    a-4  . 

U 

5-3 

U 

4-2 

f    2 

4-2 

If 

6*4 

If 

5- 

f    2 

51 

H 

7-6 

H 

6- 

i    3 

2-5 

■ 

If 

8-9 

If 

7- 

t    3 

3-8 

1* 

10-4 

If 

81 

f    3 

5-1 

U 

11-9 

If 

9-3 

f    3 

6-3 

2 

13-5 

2 

10-6 

f    3 

7-6 

H 

171 

2i 

13-5 

i    4 

3-4 

n 

211 

2f 

16-7 

f    4 

5-1 

2» 

25-6 

2f 

20-1 

f    4 

6-8 

3 

30*4 

3 

23-9 

f    4 

8-4 

3i 

41-4 

3f 

32-5 

f    4 

101 

4 

541 

4 

42-5 

i    5 

4-2 

5 

84-5 

5 

66-8 

t    5 

6-3 

6 

121-7 

6 

95-6 

f    & 

8-4 

7 

165-6 

7 

130- 

f    6 

10-6 

8 

216-3 

8 

169-9 

f    5 

12-7 

536 


WEL 


WELLS. 


WEL 


Welding f  the  operatioii  of  combining 
or  joining  two  pieces  of  iron  or 
steel,  by  bringing  the  surface  to  be 
joined  to  a  heat  nearly  equal  to 
that  of  fusion 

Wellt  in  ship-building,  a  partition  to 
endose  the  pumps,  from  the  hot- 
tom  to  the  lower  decks,  to  render 
them  accessible,  and  prevent  their 
taking  damage 

WeUs,  The  practice  of  boring  for 
water,  adopted  in  the  province  of 
Artoise,  in  France,  has  given  the 
denomination  to  those  wells  which 
are  termed  Artesian,  Wells  on 
this  principle  are  very  applicable  in 
low  level  districts  covered  with 
alluvial  deposit  or  clay;  in  such 
situations  springs  are  seldom  found, 
and  water  cannot  be  obtained  by 
sinking  an  ordinary  well,  unless  at 
a  disproportionate  cos);.  The  eastern 
part  of  Lincolnshire,  which  lies 
between  the  chalk  range  called  the 
Wolds,  and  the  sea,  is  a  case  in 
point.  It  was  discovered,  perhaps 
accidentally,  in  sioking  through 
the  clay  to  the  subjacent  chalk, 
that  water  rose  to  the  surface  in 
a  perpetual  fountain,  and  an  ample 
supply  was  obtained  over  ^e 
whole  of  that  district  by  the  sim- 
ple operation  of  boring. 

A  number  of  wells  of  this  de- 
scription have  also  been  executed 
in  the  neighbourhood  of  London 
by  perforating  the  London  clay  in- 
to the  porous  bed  of  the  plastic 
clay  formation,  and  into  the 
chalk. 

The  principle  of  operation  is 
simply  this.    The  hole  is   bored 

-  through  impervious  strata  that  do 
not  contain  water,  into  lower  strata 
that  are  fully  charged  with  it,  and 
the  water  rises  by  hydrostatic  pres- 
sure. The  height  to  which  it  will 
rise  obviously  depends  upon  the  in- 
clination of  the  strata,  and  other 
causes  which  affect  the  relative 
levels  of  the  hole  that  is  made,  and 
the  subterraneous  body  of  water 
that  has  been  tapped. 

Under  most  circumstances  it  is 

537 


necessary  to  protect  the  perforation 
that  is  made  by  sinking  iron  pipes. 
The  boring  is  thus  secured  against 
the  accident  of  the  sides  falling  in, 
and  another  advantage,  which  is 
of  some  importance,  is  obtained: 
it  may  chance  that  the  object  is  to 
obtain  a  supply  of  soft  water  which 
has  been  ascertained  to  exist  at 
a  certain  level,  and  that  the  strata 
which  have  to  be  pierced  to  get  to 
it  contain  hard  or  impure  water; 
in  such  a  case  the  boring  would  be 
continued  down  to  theproper  depth, 
and  the  pipes  being  plunged  into 
the  soft  water,  it  would  rise  through 
them,  and  any  water  or  impurity 
which  might  be  found  in  the  strata 
through  which  they  passed  would 
be  effectually  excluded.  If  it  so 
happened  that  at  a  certain  depth 
below  the  soft  water  amineral  water 
could  be  obtained,  instead  of  going 
to  the  expense  of  a  fresh  bore 
from  the  surface,  it  would  only  be 
necessary  (supposing  that  both 
would  flow  to  the  same  level)  to 
bore  through  the  pipes  already 
fixed,  to  the  mineral  water,  and 
insert  smaller  pipes  within  the 
larger  ones,  for  bringing  it  up  to 
the  surface. 

The  history  of  the  great  Artesian 
well  which  was  completed  at  Cre- 
nelle is  one  of  the  most  remark- 
able instances  of  confidence  in  the 
principle,  and  of  perseverance  in 
execution,  that  is  on  record.  The 
factsare  believed  to  be  substantially 
as  follows: — A  person  suggested 
to  the  authorities  that  an  Artesian 
well  would  supply  water  in  a  situa- 
tion where  it  was  greatly  required; 
and  after  some  discussion  it  ended 
in  Ms  undertaking  the  work  on 
the  stipulation,  '*No  water,  no 
pay."  He  bored  down  far  beyond 
the  point  at  which  he  expected  to 
have  terminated  his  labours ;  but 
no  signs  of  water  appeared:  he 
persevered,  however,  till  he  found 
that  the  expenses  had  ruined  him. 
Under  these  circumstances,  he 
consulted  the   celebrated  Arago, 


WEL 


WELL-SINKING. 


WEL 


L 


who  encouraged  him  to  proceed. 
Again  he  went  to  work,  and  after 
unparalleled  difficulties,  at  the  ex- 
piration of  six  years,  and  at  the 
depth  of  1800  feet,  the  superin- 
cumbent mass  was  bored  through, 
and  the  water  came  boiling  up  in 
such  quantities,  and  with  such 
force,  as  to  flood  the  whole  district. 

The  water,  when  flrst  obtained, 
was  extremely  foul :  the  partial  in- 
troduction of  an  Indian-rubber 
hose  is  said  to  have  remedied  this, 
and  the  water  thus  procured  from 
the  main  spring  was  quite  pure, 
and  at  a  very  high  temperature. 
Well-sinking.  The  process  of  boring 
may  be  thus  briefly  described : 

The  auger,  the  chisel,  or  any  of 
the  great  variety  of  implements 
which  are  required  to  meet  differ- 
ent circumstances  and  overcome 
the  numerous  difficulties  which  are 
experienced,  are  screwed  to  iron 
rods,  which  are  usually  from  2  to 
2^  inches  square. 

The  first  rod  which  is  attached  to 
the  tool  is  generally  about  6  feet 
long,  and  the  others  are  of  the 
uniform  length  of  20  feet.  Each 
rod  has  a  screw  at  one  end,  and  a 
tapped  socket  to  receive  a  screw  at 
the  other,  and  they  fit  universally ; 
there  is  also  a  'middle  knob'  in 
the  centre  of  each  rod,  which  is 
used  for  suspending  the  rods  al- 
ready fixed,  whilst  others  are  being 
add^  or  detached,  as  the -imple- 
ment is  lowered  into  the  bore,  or 
drawn  out  of  it. 

In  commencing  operations,  a 
stage  about  8  or  10  feet  square, 
and  20  feet  high,  is  erected,  when 
the  boring  takes  place  from  the 
surface.  The  men  who  work  the 
tool  stand  upon  this  stage,  and 
a  windlass  or  crab  is  fixed,  chiefly 
for  hoisting  and  lowering  the  rods, 
but  mechanical  power  is  also  re- 
quired for  assisting  in  the  working 
when  the  depth  is  very  great. 

A  boring  handle  is  attached  to 
the  rod,  which  is  used  for  turning 
the  tool  round  in  boring  with  an 

538       '^ 


auger,  or  in  *  jumping,'  as  is  re- 
quired when  catting  through  rock 
or  indurated  clay  with  the  chisel 
When  the  boring  has  proceeded 
till  it  is  found  difficult  to  turn  the 
rods,  or  at  such  times  as  practical 
experience  dictates,  it  is  necessaiy 
to  draw  out  the  implements  and  to 
bring  up  the  loose  material  that 
may  be  at  the  bottom  of  the  bore. 

Under  ordinary  circumstances  a 
common  windlass,  or  a  small  crah, 
gives   sufficient   power  to   work,  ■ 
hoist,  and  lower  the   rods;  hut; 
when  the  bore  is  of  great  depth,  or  > 
the  instruments  of  unusual  size,  an  > 
increase  of  mechanical  power  is  ne- 1 
cessary.   This  may  be  conveniently  , 
obtained  by  placing  a  second  crab '. 
on  another  stage ;  or,  in  extraordi- 
nary cases,  horses  may  be  applied  \ 
on  the  surface. 

An  economical  mode  of  boring ) 
has  been  adopted  with  success  on  ' 
some  parts  of  the  Continent  by , 
using  a  heavy  cast-iron  bar,  2  cvt. ; 
or  more,  armed  with  a  chisel  at 
the  lower  end,  and  surrovnded  bv  < 
a    cylinder  or   hollow    chamber, 
which  receives  through  valves  and  | 
brings  up  the  detritus  of  the  per- 1 
forated  stratum.    This  implement ' 
is  suspended  over  a  wheel  or  pulley 
fixed  above  the  spot  in  which  the 
hole  is  made,  and  is  raised  up  and 
let  fall  by  manual  labour. 

As  the  rope  is  raised  up  and 
down,  its  tortion  gives  the  chisel 
a  circular  motion,  which  varies  the 
place  of  cutting  at  each  descent. 
When  the  chamber  is  full,  the 
whole  apparatus  is  raised  quickly 
to  the  surface,  and  the  material 
it  contains  discharged. 

In  cutting  through  a  hard  stra- 
tum, or  under  circumstances  where 
iron  pipes  could  be  dispensed  with, 
this  plan  of  boring  a  hole  would 
doubtless  answer;  but  it  is  con- 
ceived that  the  bore  could  scarcelT 
be  made  sufficiently  straight  to  ad- 
mit of  pipes  being  inserted.  It  is, 
however,  a  much  less  costly  me- 
thod of  executing  the  work  where 


WEL 


WHARF. 


WHA 


it  can  be  made  to  apply,  and  is  well 
vrorth  attention. 
Well-staircase,  a  winding  staircase  of 
ascent,  or   descent,  to    different 
parts  of  a  building,  so  called  from 
the  walls  enclosing  it  resembling  a 
well,  called  frequently  a  geometri- 
cal  staircase 
Weold^  or  Weald  (Saxon),  a  forest 
Wharfs  a  levelled  surface,  terrace,  or 
embankment,  formed  on  a  river  or 
canal  bank,  or  sea- coast,  to  facili- 
tate the  landing  and  embarkation 
of  persons  and  goods,  and  protected 
by  an  artificial  frontage  or  struc- 
ture of  masonry  or  other  materials. 
The  natural  form  of  banks  and 
coasts,  unless  defined  by  masses  of 
rock,  is  usually  shelving  or  inclined, 
so  that  the  depth  of  water  is  gra- 
dually reduced,  and  thus  prevents 
the  close  approach  of  floating  ves- 
sels.  By  the  construction  of  wharf- 
walls,  which  are  either  extended 
into  the  deep  water,  or  the  founda- 
tions of  which  are  sunk  so  as  to 
permit  the  subsequent  removal  of 
the  bank,  and  thus  bring  deep  water 
into  contact  with  them,  vessels  are 
enabled  to  come  close  alongside, 
and  thus  discharge  or  receive  their 
cargoes  directly  from  the  wharf. 
"Wharf-walls  are  constructed  of  va- 
rious materials,    but  are    always 
formed  with  a  slope  or  batter  out- 
wards towards  the  base,  in  order  to 
give  greater  stability  to  them,  and 
to  resist  the  action  of  the  tide  and 
the  waves.    Much  theory  has  been 
expended  in  attempts  to  determine 
the  precise  forms  which  should  be 
given  to  these  structures,  and,  ac- 
cordingly, some  engineers  approve 
of  plane-faced  walls,  while  others 
prefer  curved  faces;  and  another 
theory  has  been  started  to  explain 
that  a  perfectly  vertical  face  is  the 
best  of  all  adapted  to  resist  the  in- 
fluence of  waves.    Whether  this 
position  be  theoretically  correct  or 
not,  however,  the  value  of  an  ex- 
tended base,  in  giving  stability,  is 
too  well  known  to  need  demonstra- 
tipn,  and  derives  support  from  that 

539 


intuitive  kind  of  feeling  which  pro- 
ceeds directly  from  the  evidence  of 
our  senses.  Adopting  the  inclined 
plane  face  as  a  good  practical  one 
for  wharf-walls,  the  rate  of  inclina- 
tion or  batter  may  be  determined 
from  1  in  8  to  lin  12,  that  is,  with 
a  total  divergence  from  the  perpen- 
dicular of  i  or  -j^  of  the  totalheight, 
being  from  1  to  1^  inch  in  a  foot. 
The  front  of  the  wall,  if  of  masonry, 
may  be  protected  by  a  row  of  sheet 
piling,  either  of  timber  or  iron.  In 
the  former  case,  the  piles  are  driven 
close  together,  and  bound  along 
the  top  with  a  horizontal  tie  or 
waling  firmly  bolted  to  the  piles. 
If  iron  piling  is  used,  the  piles  are 
driven  at  intervals  of  from  three 
to  five  feet,  and  cast-iron  plates 
fitted  in  between  them,  being  se- 
cured within  grooves  formed  in  the 
sides  of  the  piles.  The  Brunswick 
Wharf,  at  Blackwall,  affords  a  good 
example  of  this  description  of 
piling.  The  masonry  of  the  wall  is 
founded  upon  the  piling,  the  length 
and  closeness  of  the  piles  being 
determined  with  reference  to  the 
nature  of  the  subsoil,  and  the  whole 
of  them,  are  driven  to  a  firm  bot- 
tom and  levelled  on  the  heads, 
being  strongly  secured  in  their  po- 
sition by  means  of  longitudinal  and 
transverse  ties  or  beams,  on  which 
the  first  course  of  footings  was  built. 
The  durability  of  these  walls  is 
known  to  depend  greatly  upon  the 
kind  of  mortar  or  cement  used  in 
connecting  the  masonry  or  brick- 
work. Cements  known  as  water- 
cements,  formed  with  lime  which 
has  the  property  of  hardening  under 
water,  should  be  preferred  to  all 
others.  The  thickness  of  the  wall 
must  depend  upon  its  height  and 
the  nature  of  the  materials  behind 
it.  If  these  are  likely  to  press  se- 
verely against  the  wall,  such  as 
days  liable  to  hold  great  quantities 
of  water,  &c.,  the  thickness  of  the 
wall  will  be  required  to  be  greater 
than  if  gravel,  or  other  non-reten- 
tive material,  forms  the  backing. 


WHE 


WHEEL-CUTTING  MACHINE. 


WHE 


Strong  ties  of  iron  should  in  all 
cases  be  secured  to  the  front  of  the 
wall,  passing  through  it,  and  being 
secured  by  plates  and  keys  in  the 
front,  and  extending  backward  to 
a  considerable  distance,  and  se- 
cured to  a  row  of  piling  driven  into 
the  solid  ground.  These  land-ties 
will  also  considerably  assist  the 
wall  in  resisting  the  forward  pres- 
sure of  the  soil  behind  it.  Imme- 
diately at  the  back  of  the  wall  a 
firm  body  of  concrete,  or,  at  least, 
well-puddled  clay,  should  be  in- 
troduced. Whichever  of  these  is 
used  as  a  backing,  it  should  be 
consolidated  as  much  as  possible, 
and  it  will  thus  resist  the  admission 
of  moisture  behind  the  wall,  which 
is  indispensable  to  secure  its  per- 
manent durability.  The  concrete 
should  be  cast  in  from  a  height 
above  its  intended  position,  and 
allowed  to  set  before  it  is  filled  in ; 
and  if  clay  be  substituted,  it  should 
be  thoroughly  well  rammed  in,  and 
made  as  soUd  as  possible. 

Wheal  The  ancient  Cornish  called 
a  mine  Ai««/,  which  has  been  cor- 
rupted into  wheal. 

Wheel  and  Axle,  This  machine  is  so 
named  by  reason  of  its  consisting 
of  a  wheel  and  cylinders,  having  a 
common  axis  with  pivots  fixed  in 
its  extremities,  on  which  the  whole 
may  revolve.  This  very  simple  and 
us^ul  contrivance,  although  usual- 
ly designated  a  second  mechanical 
power,  requires  the  consideration 
of  no  other  principles  than  those 
adduced  for  the  lever ;  it  is  notliing 
but  a  lever,  having  the  radius  of 
the  wheel  for  one  arm,  and  that  of 
the  cylinder  or  axle  for  the  other, 
the  fulcrum  being  the  common 
centre  of  both.  This  machine  is 
also  termed  the  *  Perpetual  Lever ;' 
for  since  the  power  and  the  resist- 
ance operate  respectively  at  the 
circumference  of  a  circle  revolving 
about  an  axis,  it  is  obvious  that 
the  rotation  must  maintain  the 
continuity. 

Wheels,  in  locomotive  engines:  the 


well-known  invention  for  ob- 
taining a  rolling  progressive  mo- 
tion. They  receive  names  coire- 
sponding  to  the  part  of  the  engine 
or  tender  they  support ;  as  leading, 
trailing,  &c.  Driving  wheels  nn 
in  size  from  4  feet  6  inches  up  to 
10  feet  diameter.  Lieading  and 
trailing  wheels  vary  frrom  3  feet 
up  to  4  feet  6  inches  in  diameter. 
Tender  wheels  are  usnally  about 
the  same  size  as  the  leading  and 
trailing  wheels  of  the  engines  thej 
are  attached  to. 
WheeUcviting  machine  j  a  machine  for 
cutting  out  the  teeth  of  wheels. 
The  most  perfect  machines  for 
shaping  the  teeth  of  wheels  are 
those  invented  by  Mr.  Lewis,  of 
Manchester,  which  are  adapted  for 
cutting  the  teeth  of  spur,  bevel, 
and  worm  wheels,  of  either  metal 
or  wood.  The  principal  working 
parts  of  these  machines  and  the 
mode  of  action  is  as  follows: 

Two  side  frames  have  angular 
ridges  from  end  to  end,  to  fit  into 
corresponding  grooves  in  the  bot- 
tom of  a  travelling  frame:  this 
frame  can  be  adjusted  by  a  screv 
moved  by  a  hand-wheel  at  the  back 
of  the  machine :  at  the  front  of  the 
machine  is  a  strong  spindle,  placed 
vertically,  to  carry  the  work  which 
is  fixed  on  the  top  of  it,  and  at  the 
lower  part  is  a  large  w(»in-wheel 
moved  by  a  screw,  to  which  is 
connected  a  train  of  three  wheek : 
the  sizes  of  the  first  and  third 
wheels  must  be  such  that  half  a 
revolution  of  a  handle,  which  falls 
into  a  notch  after  each  half-revo- 
lution, shall  turn  the  work  so  that 
any  point  in  the  pitch-Une  of  it 
will  move  through  a  distance  equal 
to  the  pitch.  To  the  travelling 
frame  a  slide  is  attached  by  bolts 
and  joints,  in  such  manner  that  it 
may  be  fastened  to  act  vertically, 
or  at  an  angle  in  the  direction 
either  of  the  length  or  breadth  of 
the  machine.  The  cutter,  and  its 
wheels  for  diminishing  the  speed 
and  pulley  for  communicating  mo- 


540 


:  i 


WHI 


WINCH  AND  AXLE. 


tion  to  it,  are  carried  by  the  slide. 
The  cutter  is  a  circular  piece  of 
steel  notehed  like  a  saw,  and  shaped 
to  fit  the  spaces  between  the  teeth 
of  the  wheel,  and  is  raised  or  low- 
ered by  a  rack  at  the  back  of  the 
slide,  worked  by  a  pinion  and  han- 
die.  The  travelling  frame  and  slide 
being  adjusted  to  the  work,  and 
the  suitable  wheels  arranged  for 
taming  it  the  given  distance,  the 
machine  is  set  in  motion  and  the 
revolving  cutter  pressed  down  upon 
the  rim  of  the  wheel  by  the  handle 
and  rack  till  the  space  has  been 
cut;  the  cutter  is  then  raised,  and 
by  giving  half  a  revolution  to  the 
handle  attached  to  the  worm-wheel 
apparatus,  the  spindle  and  work  are 
turned  so  that  the  latter  is  in  pro- 
per position  for  the  cutter  to  act 
again.  For  a  spur-wheel  the  slide 
acts  vertically,  for  a  bevel-wheel  it 
acts  at  the  requisite  angle  in  the 
direction  of  the  length,  and  for  a 
worm-wheel  at  an  angle  in  the 
direction  of  the  breadth  of  the 
machine. 

Whim,  a  machine  used  for  raising 
ores,  &C.,  worked  by  horses,  steam, 
or  water 

Whim^haft,  in  mining,  the  shaft  by 
which  the  stuff  is  drawn  out  of  the 
mine  by  the  horse  or  steam  whim 

Whispering  gallery,  a  curvilinear  cor- 
ridor or  balcony  within  the  cupola 
of  St.  Paul's  cathedral,  London, 
and  in  other  ecclesiastical  build- 
ings 

Whiie  Chalk  is  a  well-known  native 
carbonate  of  lime,  used  by  the 
artist  only  as  a  crayon,  or  for 
tracing  his  designs ;  for  which  pur- 
pose it  is  sawed  into  lengths  suited 
to  the  port-crayon.  White  crayons 
and  tracing  chalks,  to  be  good,  must 
work  and  cut  free  from  grit.  From 
this  material  both  whiting  and  lime 
are  prepared,  and  are  the  bases  of 
many  common  pigments  and  co- 
lours used  in  distempering,  paper- 
staining*  &c. 

Wicker'tDQTky  at  an  early  date,  was 
occasionally  employed  for  the  roof- 

541  2  a 


WIN 

ing,  if  not  for  the  eitire  coiito^ 
tion,  of  churches 
Wicket,  a  small  gate  or  door  vdthin 
or  a  part  of  a   massive   or  large 
for  the  passage  of 


part 
door  or  gate 
pedestrians 

WiUow  wood  is  of  many  varieties  •  it 
IS  perhaps  the  softest  and  liirhtent 
of  English  wood^;  it  i,  pia^Jl  j^ 
chips,  and  used  for  many  simnle 
purposes  *^ 

Winkle,  a  plaited  linen  cloth  which 
nuns  wear  about  their  necks ;  also 
a  flag  or  streamer 

Winch  or  Wince,  in  mining,  the  wheel 
and  axle  frequently  used  to  draw 
water,  &c.  in  a  kibble  by  a  rope 

Winch  and  Axle,  >  machine  consti. 
tuting  a  small  windlass,  and  con- 
sisting  of  a  cylinder  of  wood  which 
is  capable  of  turning  on  its  axis 
between  two  upright  posts  of  the 
same  material,  or  between  the  ends 
of  a  cast-iron  frame :  a  lever  at 
one  or  at  each  extremity  of  the 
cylinder  is  attached  to  an  iron  axle 
passing  through  the  latter  at  right 
angles  to  its  direction,  and  is  Air- 
nished  with  a  handle,  which  is 
parallel  to  that  axle.    The  name 
winch  is  given  to  a  lever  or  handle 
of  this  kind,  and  the  word  is  sup- 
posed to  be  derived  from  the  verb 
guineher,  signifying,  in  old  French, 
to  turn,  or  bend  in  a  curvilinear 
manner.    The  machine  is  used  to 
raise  a  weight  vertically,  or   to 
draw  an  object  towards  it ;  for 
which  purposes  the  object  is  con- 
nected with  it  by  a  rope  or  chain 
which  continually  passes  over  the 
curved  surface  of  the  cylinder  as  the 
latter  is  made  to  turn  on  its  axis 
by  a  man  acting  at  the  handle. 
Since  the  cylinder  revolves  once 
while  the  handle,  or  the  extremity 
of  the  lever  to  which  it  is  attached, 
is  made  to  describe  the  circumfer- 
ence of  a  circle,  it  is  evident  that 
the  mechanical  power  of  the  ma- 
chine is  precisely  that  of  the  wheel 
and  axle.    When  of  a  simple  form, 
it  is  employed  to  raise  water  from 
a  well,  and  earth  or  8om«  other 


WIN 


WINCH  AND  AXLE. 


WIN 


mftteiial  from  the  shaft  of  a  small 
mine ;  and  one  of  a  complex  nature 
is  used,  hy  means  of  a  crane,  to 
raise  casks  or  heavy  packages  from 
the  ground  to  the  upper  part  of 
a  huilding. 

When  great  weights  are  to  be 
raised,  the  machine  is  usually  fixed 
in  a  frame  of  cast  iron,  which  is 
rectangular  on  the  plan,  but  its 
extremities  or  laces  have  the  form 
of  a  triangle,  or  of  the  letter  A. 
The  axle  of  the  cylinder  is  sup- 
ported on  a  horizontal  bar  at  the  |- 
middle  of  each  end  of  the  frame, 
and  to  the  cylinder  is  attached  a 
toothed  wheel  which  turns  with  it 
on  the  common  axis:  above  this 
wheel,  and  parallel  to  the  cyhnder, 
is  an  iron  axle  which  carries  a 
pinion  with  teeth  working  in  those 
of  the  wheel,  and  causing  the  latter 
to  revolve,  the  pinion  itself  being 
turned  by  means  of  the  lever  and 
handle  at  one  or  at  each  extremity 
of  the  frame.  A  machine  of  this 
kind  is  called  a  crab;  and  when  a 
weight  is  to  be  drawn  horizontally 
or  raised  above  the  cylinder,  the 
machine  must  of  course  be  bolted 
to  the  floor  or  firmly  fixed  in  the 
ground,  in  order  to  prevent  it  from 
being  moved  from  its  place.  In 
such  machines  there  is  generally, 
at  one  extremity  of  the  cylinder,  a 
wheel  having  on  its  circumference 
teeth  like  those  of  a  saw ;  and  a 
cUek  or  catch,  which  turns  freely 
on  a  pin,  is  attached  by  that  pin  to 
the  side  of  the  frame  in  such  a 
manner  that  it  may  fall  between 
the  teeth.  By  this  contrivance,  if 
the  handle  should  break,  or  the 
moving  power  be  taken  off  while 
the  weight  is  suspended  in  the  air, 
the  latter  is  prevented  from  de- 
scending. 

Machines  of  this  kind  are  occa- 
sionally constructed,  which  have 
the  power  of  holding  the  weight  in 
any  part  of  its  ascent  or  descent 
without  a  ratchet-wheel  and  catch. 
The  only  disadvantage  attending 
the  machine,  when  compared  with 

542 


an  ordinary  winch  or  capstan,  is, 
that  it  requires  a  much  greater 
quantity  of  rope  to  raise  or  move  tke 
object  tiirough  any  given  distance. 
It  was  first  proposed  in  Europe  by 
Mr.  George  Eekhardt,  but  machines ' 
of  a  like  kind  have,  it  is  said,  loig 
been  in  use  in  the  East. 

The  vnnch  i»  employed  in  the 
common  jack,  which  is  used  t«  lift  _ 
great  weights,  or  to  move  them 
through    small    distances.     The 
handle  turns  a  pinion  with  teeth, 
which  act  on  others  at  the  drcim- 
ference  of  a  small  wheel ;  and  sn ' 
the  axle  of  this  is  a  pinion  with 
teeth,  which  work  in  those  of  a 
rack-rod.    The  axles  cxf  the  wheel 
and  pinions  being  let  into  the  sides  ■ 
of  a  case  of  wood  or  iron,  the  re- ' 
vohition  of  the  wheel  produces  a 
rectilinear  motion  of  the  rack;  snd  < 
one  end  of  the  case  beingfixedto  the 
ground,  or  against  an  immoveable 
object,  the  extremity  of  the  rack ' 
at  the  opposite  end  forces  forward , 
the  body  which  is  to  be  displaced.  ■ 
Sometimes,  instead  of  a  rack,  the ' 
machine  is  furnished  with  a  wheel 
whose  axle  is  hollow,  and  cat  in 
the  form  of  a  concave  screw :  withiii 
this  screw  is  one  of  the  convex 
kind,  which  by  the  revolution  of 
the  wheel  and  its  axle  is  made  to 
move  in  the  direction  of  the  latttf, 
and  thus  to  press  before  it  the  ob- , 
ject  which  is  to  be  removed.    This ! 
machine  has,  however,  consider- 
able friction. 

The  force  exerted  by  a  man  in ' 
turning  a  winch  vertiodly,  varies 
according  to  the  position  of  the 
lever  with  respect  to  the  horizon. 
When  the  lever,  or  that  part  which 
is  perpendicular  to  the  sixle,  is  per- 1 
pendicutar  to  the  ground,  and  the  i 
handle  is  at  the  highest  or  lowest  ; 
part  of  the  circle  described  by  the  I 
end  of  the  lever,  the  man  either , 
pushes  the  handle  directly  from  j 
him  or  pulls  it  directly  towards ' 
him ;  and  in  each  case  he  exerts 
power  which  is  estimated  at  27  o 
30  pounds ;  but  when  the  lever  i  ■ 


WIN 


WIND. 


WIN 


in  a  horizontal  position,  the  man 
either  throws  a  great  portion  of  his 
weight  on  the  handle  to  press  it 
down,  or  he  exerts  his  muscular 
force  in  a  direct  manner  to  pull  it 
upwards ;  and  the  force  exerted  in 
these  positions  is  estimated  at  140 
or  160  pounds.  The  force  exerted 
must  verj  evidently  have  different 
values  between  these  quantities  in 
other  positions  of  the  virinch ;  and 
the  practice  is  to  cause  two  men 
to  work  at  the  same  time  to  turn 
the  machine,  one  being  at  each 
extremity  of  the  axle  of  the  cylin- 
der. The  levers  of  the  two  winches 
are  placed  at  right  angles  to  one 
another;  consequently,  when  one 
man  is  pushing  or  pulling  horizon- 
tally, the  other  is  pressing  or  pull- 
ing vertically,  and  thus  the  opera- 
tion of  turning  goes  on  with  nearly 
uniform  intensity ;  the  first  man 
working  in  the  least  favourable 
position  when  the  other  is  working 
in  that  which  is  most  so. 

Wind  (instrument  for  measuring  the 
force  and  velocity  qf)  :  a  fly  (re- 
sembling that  of  a  revolving  ventila- 
tor, or  the  sails  of  a  wind-mill)  is 
fixed  to  the  small  end  of  the  vane  of 
a  weather-cock,  so  as  to  be  turned 
vrith  its  circular  disc  to  the  wind ; 
and  it  consequently  revolves  by  the 
action  of  the  wind  with  a  rapidity 
increasing  as  the  force  of  the  wind 
increases.  The  revolutions  of  the 
axis  of  this  fly  are  converted  by  a 
train  of  toothed  wheels  and  screws 
into  a  vertical  motion,  by  which  a 
pencil  is  carried  downwards,  touch- 
ing the  surface  of  a  vertical  cylin- 
der, the  cylinder  having  the  axis 
of  the  weathercock  for  its  axis. 
As  the  vertical  rod  on  which  the  • 
pencil  slides  is  attached  to  the 
vane  of  the  weathercock,  the  point 
of  the  compass  from  which  the 
wind  blows  is  recorded  on  the  side 
of  the  cylinder  on  which  the  mark 
is  made ;  while  the  quantity  of  the 
wind  is  represented  by  the  extent 
of  the  descent  of  the  pencil. 

Wind-beam  f  in  ancient  carpentry,  a  ' 

543 


cross-beam  used  in  the  principals 
of  many  ancient  roofs,  occupying 
the  situation  of  the  collar  in  mo- 
dem king-post  roofs 
Winding^  in  s*hips,  twistingf  on  an 

uneven  surface 
Winding  engines.    In  winding  engines 
for  drawing  coals  from  a  pit,  where 
a  given  number  of  strokes  are  re- 
quired in  drawing  a  corf,  the  dia- 
meter of  the  roll  at  the  first  lift  must 
be  ascertained.     In  this  case  the 
engine  is  supposed  to  have   flat 
ropes,  such  as  are  generally  used, 
and  which  lie  upon  each   other. 
To  find  the  diameter  of  a  rope-roU 
at  the  first  lift,  it  is  necessary  to 
know  the  depth  of  the  pit,  the 
thickness   of  the  rope,   and  the 
number  of  strokes  which  the  en- 
gine  is  intended  to  make  in  draw- 
ing up  a  corf  or  curves ;  then,  the 
thickness  of  the  rope  being  known 
and  the  number  of  strokes,  the 
thickness  of  the  ropes  upon  the 
roll  can  be  determined,  let  the  dia- 
meter of  the  roll  be  what  it  may. 
Suppose  the  thickness  of  the  rope 
to  be  1  inch,  and  the  number  of 
strokes  10 ;  then  the  radius  of  the 
roll  is  increased  10  inches,  or  the 
diameter  is  increased  20  inches, 
whatever  that  diameter  may  be. 
WindlasSf  in  mechanics,  a  machine  by 
which  a  rope  or  lace  is  wrapped 
round  a  cylinder :  in  navigation,  a 
horizontal  machine  of  strong  tim- 
ber, used  in  merchant  ships  for 
heaving  up  the  anchor,  instead  of 
a  capstan 
Wind-millj  a  mill  which  derives  its 
motive  power  from  the  impulse  of 
the  wind.    The  building  contain, 
ing  the  mill-work  is  usually  lofty, 
and  placed  on    elevated  ground. 
The  machinary  consists  of  a  shaft, 
upon  one  extremity  of  which  arms 
radiate  at  right  angles,  similarly  to 
the  spokes  of  a  wheel :  upon  these, 
Tanes  or  sails  are  set  at  a  small 
angle,  (about  22^)  By  this  means 
the  wind,  blowing  directly  upon 
the  area  occupied  by  the  vanes, 
acts  obliquely  upon  the  whole  of 


WIN 


WOOD. 


WOO 


them,  causing  them  all  to  move  in 
a  direction  transversely  to  that  of 
the  wind.  Suitable  means  are 
provided  for  bringing  the  sails  into 
a  position  to  confront  the  current 
of  the  wind.  The  motion  of  the 
sails  is  transferred  by  gearing  to 
any  machinery  required  to  be 
driven,  which  is  most  commonly 
mills  for  grinding  corn.  Wind- 
miUs  were  formerly  extensively 
employed,  in  Holland,  to  give  mo- 
tion to  pumps  for  the  drainage  of 
land.  The  power  of  the  wind  is 
uncertain  and  variable  in  its  inten- 
sity, and  its  application  as  a  prime 
mover  for  mechanical  purposes  is 
consequently  limited. 
Windows  were  almost  unknown  in 
the  religious  and  other  monumental 
structures  of  the  Egyptians,  Greeks, 
and  Romans,  but  they  constitute 
an  essential  and  distinguishing 
feature  of  the  Gothic,  to  which 
style  they  stand  in  the  same  rela- 
tion as  Orders  do  to  the  temple 
architecture  of  antiquity. 

Windows  admit  of  very  rich  and 
varied  decoration,  and  those  in 
Beccles  church,  Suffolk,  (repre- 
sented on  the  opposite  page,)  are 
beautiful  examples.  The  varied 
exuberance  of  fancy  displayed  in  the 
tracery  may  possibly  be  accounted 
for  by  supposing  each  to  have  been 
the  gift  of  some  pious  individual, 
who,  while  he  perpetuated  his  mu- 
nificence, nuirked  also  his  taste  and 
ingenuity. 

The  practice  of  window  tracery 
every  where  had  its  origin  in  win- 
dow-groupinfff  placing  two  or  three 
lancet  windows  beside  each  other, 
and  one  or  more  foil  or  rosette 
windows  above  and  between  their 
heads,  in  order  to  fill  out  the 
arched  cell  of  the  vaulting,  which 
then  necessarily  gave  the  whole 
group  an  arched  outline ;  and  this 
was  indicated  by  a  general  drip- 
mould  or  label.  It  then  became 
desirable  to  lighten  the  irregular 
shaped  masses  of  stone  left  between 
the  perforations,  and  this  was  done 

545 


by  piercing  these  masses,  or  span- 
drils,  and  reducing  the  solid  frame 
of  each  foil  or  rosette  to  an  equal 
thickness  all  round,  as  if  several 
such  frames  or  rings  were  packed 
into  one  great  arched  opening, 
which  henceforth  was  regarded  as 
one  window  instead  of  several. 
(For  further  illustration,  see  art. 
Tracery.) 

Wind-saily  in  navigation,  a  sort  of 
ventilator,  consisting  of  a  wide 
tube  of  canvas  shaped  like  a  fun- 
nel, to  convey  a  stream  of  fresh 
air  downwards  to  the  hold  and 
lower  deck  of  a  ship 

Wing  transom,  in  ships,  the  upper- 
most transom  of  the  stem-frame 

Winze,  in  mining,  a  sinking  in  a  lode 
communicating  with  one  level,  for 
proving  the  lode  or  ventilating 
the  drivings 

Wipers,  the  cogs  of  a  horizontal  wheel 

Wood,  in  its  raw  state,  contains  a 
large  amount  of  water.  This  water 
contains  more  or  less  soluble  mine- 
rals, and  is  called  sap.  By  drying 
wood,  a  great  part,  but  not  all,  of 
this  water  is  evaporated.  If  wood 
is  dried  in  a  closed  vessel,  and  then 
exposed  to  the  atmosphere,  it 
quickly  absorbs  moisture ;  but  the 
moisture  thus  absorbed  is  much 
less  than  the  wood  originally  con- 
tained. 

The  amount  of  water  varies  in 
difi^erent  kinds  of  wood,  and  also 
varies  according  to  the  season. 
Wood  cut  in  the  month  of  April 
contains  from  10  to  20  per  cent, 
more  water  than  that  cut  in  the 
month  of  January. 

The  following  Table  shows  the 
percentage  of  water  in  different 
kinds  of  wood  dried  as  far  as 
possible  in  the  air: 


Beech 

Poplar     ...... 

Sugar  and  common  Maple 
Ash     ......     . 

Birch  ...     .... 

Oak,  red  ......     34-7 

Oak,  white    .....     35-5 


\B-6\ 
260  \ 
270  \ 
280  \ 

30-0 ; 


woo 


WROUGHT  IRON. 


WRO 


Pine,  white 370 

Chestnut 382 

Pine,  red 390 

Pine,  white 45-5 

Linden 471 

Poplar,  Italian  ....  48-2 

Poplar,  hlack    ....  51-8 

Wood  cut  during  the  months  of 
December  and  January  is  not  only 
more  solid,  but  it  will  dry  faster 
than  at  any  other  period  of  the 
year,  because  the  sap  by  that  time 
has  incorporated  a  great  part  of  its 
soluble  matter  with  the  woody 
fibre ;  what  remains  is  merely  wa- 
ter. When  the  sap,  during  the 
months  of  February,  March,  and 
April,  rises,  it  partly  dissolves  the 
woody  fibre;  and  the  drying  of  the 
wood  is  not  only  retarded,  but  the 
wood  is  weakened,  in  consequence 
of  the  solid  matter  thus  held  in 
solution. 

The  difference  in  chemical  com- 
position of  the  woody  fibre,  in 
most  kinds  of  wood,  is  but  slight, 
as  the  following  analytical  Table 
shows :  Qy. 

Carbon,  drogen. 
Sugar  Maple  52-65    5*25 
Oak    .    .    .  49-43    607 
Poplar,  black  4970    6-31 
Pine   .    .    .  5011     6*31 


Oxy- 
gen. 
4210 
44-50 
43-99 
43-58 


Wood  is  generally  bought  by 
admeasurement,  and  its  specific 
gravity  is  directly  in  proportion  to 
its  amount  of  carbon,  hydrogen, 
and  oxygen.  The  following  Table 
shows  the  specific  gravity  of  wood. 
Water  =  1000 : 


Green. 

Air-dried. 

Oak,  white  . 

1-0754 

0-7075 

Oak,  red 

1-0494 

0-6777 

Poplar     .    . 

0-9859 

0-4873 

Beech      .    . 

0-9822 

0-5907 

Sugar  Maple 

0-9036 

0-6440 

Birch       .    . 

0*9012 

0-6274 

Pine,  red 

0-9121 

0-5502 

Pine,  white 

0-8699 

0-4716 

Ebony     .     . 

1* 

1-2260 

Guaiac   (lignum' 
vitse)    .    .     .^ 

It 

1-3420 

Woo^*s  engine^  a  steam  engine  so 
calledfrom  its  inventor's  name,  with 
two  combined  cylinders  of  differ- 
ent diameter,  the  eduction  passage 
of  the  smaller  cylinder  commiinicat- 
ing  with  the  steam  passages  of  the 
other;  high-pressure  steam  being 
used  in  the  small  cylinder,  and 
made  to  act  expansively  in  t&e 
large  one,  the  steam  being  after- 1 

.  wards    condensed    in    the    usual  i 
manner.      By    this    arrangement 
steam  is  economized,  and  a  con- . 
siderable  saving  of  fuel  is  efiTected. 

Worky  in  mining,  ores  before  they  are 
cleaned  and  dressed  | 

Working-bifft  in  mining,  ugnifiet 
sufficiently  large  for  a  man  to  work 
in 

Working  drawmgs  consist  of  plans, 
elevations,  sections,  and  details  in 
full,  of  the  whole,  and  of  all  the 
parts  of  an  edifice,  to  as  large  a 
scale  as  may  be  found  convenient ; 
generally  made  in  outline,  except- 
ing  the  sectional  parts,  which  are  ! 
mostly  shadowed,  in  order  to  make 
them  more  obvious  to  the  work- 
man, for  whose  use  these  drawings 
are  made 

Worm-wheelf  a  wheel  haying  teeth 
formed  to  fit  into  the  spiral  spaces 
of  a  screw,  so  that  the  wheel  may 
be  turned  by  the  screw  1 

Wreathf  in  heraldry,  that  which  is 
between  the  mantle  and  the  crest, , 
called  also  a  torce ;  also  a  boar's  i 
tail,  so  termed  among  hunters         ' 

Wrought  iron.  The  chemical  differ-  | 
ence  between  cast  iron  and  wrought  J 
iron  consists  principally  in  the  de- 
gree in  which  foreign  matter  is  pre-  ; 
sent  in  each ;  which  is  in  larger  , 
amount  in  the  former  than  in  the  ' 
latter.  This  rule  is  applicable  only  I 
to  a  given  cast  iron,  and  to  the  ' 
wrought  or  bar  iron  which  is  made  i 
from  it.  There  are  many  cases  in  j 
which  wrought  iron  contains  a 
larger  amount  of  impurities  than  ' 
cast  iron,  and  still  continues  mal- 
leable ;  while  cast  iron  of  the ' 
same  composition  may  be  very  hard  • 
and  brittle.    Berzelius  detected  18 


546 


WRO 


WROUGHT  IRON. 


WRO 


per  cent,  of  silcx  in  a  certain  kind 
of  bar  iron,  which  was  still  mallea- 
~ble  and  useful.  One-tenth  of  that 
amount  of  silex  will  make  cast  iron 
brittle.  The  foreign  matters  gene- 
rally combined  with  pig  iron  are, 
carbon,  silicon,  silex,  sulphur,  phos- 
phorus, arsenic,  zinc,  manganese, 
titanium,  chrome,  aluminium,  mag- 
nesium, and  calcium.  Each  of  these 
tends  to  make  iron  brittle ;  there- 
fore, in  converting  cast  into  wrought 
iron,  it  is  necessary,  as  far  as  pos- 
sible, to  remove  them. 

The  main  difference  between  pig 
and  wrought  iron  consists  in  their 
mechanical  structure,  .or  aggregate 
form.  Pig  iron  is  a  homogeneous 
mixture  of  impurities  and  metal. 
Wrought  or  bar  iron  is  a  mixture 
of  iron  more  or  less  pure  with  a 
mass  of  homogeneous  impurities, 
or  cinder,  the  latter  filling  the  cre- 
vices between  the  crystals  of  the 
iron.  Iron  being  fusible  in  pro- 
portion to  the  carbon  it  contains, 
if  pig  metal  is  melted,  and  the  cin- 
der surrounding  it  exposed  to  the 
atmosphere,  the  carbon  will  be 
volatilized  in  the  form  of  carbonic 
add,  and  iron  of  grealj^r  or  less 
purity  will  remain.  To  keep  this 
iron  liquid,  a  higher  temperature  is 
required:  unless  the  temperature 
is  raised,  it  will  crystallize.  In  this 
state  of  metamorphosis  its  infusi- 
bility  will  increase,  and  after  the 
expulsion  of  the  carbon,  it  will 
contract  into  a  solid  mass  in  oppo- 
sition to  the  highest  possible  heat. 
By  stirring  and  mixing  the  pasty 
iron,  small  crystals  are  formed ;  at 
first,  on  account  of  the  partial 
fusing  of  the  iron,  in  small  parti- ' 
cles;  but,  as  the  fusibility  dimi- 
nishes, these  particles  unite  by  the 
force  of  cohesion  ;  and  the,  bodies 
thus  formed  may,  by  exposure  to  a 
higher  heat,  be  welded  together. 
The  mixing  of  cinder  and  iron  will 
prevent  the  latter  from  forming 
large  crystals :  this  result,of  course, 
wiU  be  more  easily  prevented  by 
diligent  than  by  tardy  manipula- 

547 


tion.  Where  the  pig  iron  is  of  such 
a  nature  as  to  keep  liquid  while 
the  work  goes  on  slowly,  still  bet- 
ter results  will  be  obtained.     This 
process  is  analogous  to  that  of  salt 
boiling,  in  which,  by  stirring  the 
brine,  the  formation  of  large  crys- 
tals is  prevented.     If  the  crystals 
of  iron  thus  formed  cohere,  they 
produce,  under  the  influence  of 
motion,  a  porous,   spongy  mass, 
whose  crevices  are,  if  not  filled,  at 
least  coated,  with  cinder.    If  these 
masses,  which  are  the  loups  or  balls 
at  the  puddling  furnaces,  are  shin- 
gled or  squeezed,  the  crystals  of 
iron  will  not  unite,  but  form  coated 
cells  with  a  film  of  cinder,  of  greater 
or  less  thickness,  according  to  the 
fusibility  of  the  cinder.     Iron  in  a 
connected  form,  and  cinder  in  sepa- 
rate cells,  are  thus  blended  in  one 
homogeneous  mass.  The  more  this 
iron  is  stretched,  the  more  it  forms 
fibres.    Fibrous  bar  iron  resembles 
hickory  wood,  in  being  a  combina- 
tion of  fibres  and  spaces.     In  bar 
iron,  these  spaces  are  filled  with 
cinder.   When  other  circumstances 
are  equal,  the  strength  of  the  iron 
will  be  proportional  to  the  fineness 
of  the  fibres.     That  portion  of  the 
iron  which  is  not  melted,  which 
crystallizes  too  fast,  or  whose  pre- 
mature  crystallization  cannot  be 
prevented,  is  in  the  condition  of 
cast  metal,  and  cannot  be  convert- 
ed  into  fibrous  wrought  iron.    In 
the  puddling  furnace  it  is  necessary 
to  prevent  crystallization  by  ma- 
nual labour. 

If  the  characteristic  between 
wrought  and  pig  iron  consists  only 
in  a  well-regulated  mechanical  mix- 
ture of  cinder  and  iron,  fibrous  iron 
should  be  producible  from  any  cast 
iron,  whether  purified  or  not :  this 
is  actually  the  case.  Very  fibrous 
bar  iron,  which  is  strong  and  mal- 
leable, is  made  from  very  inferior 
cast  metal,  from  which  no  impurity 
has  been  removed.  At  Hyanges,  in 
France,  very  inferior  metal  is  con- 
verted by  a  cheap  and  skilful  pud- 


WRO 


WROUGHT  IRON. 


WRO 


dling  process,  into  a  very  fibrous 
bar  iron,  of  great  strength  and 
ductility.  Bat  this  iron  is  puddled 
and  re-heated  at  th^  lowest  possi- 
ble heat ;  it  is  then  rolled,  and  is 
ready  for  the  market.  For  hoops, 
rails,  and  nails,  it  is  a  Tery  useful 
article,  but  is  of  no  use  to  the 
blacksmith.  Heated  to  any  tem- 
perature above  that  of  the  puddling 
and  re-heating  furnaces,  it  returns 
to  its  primitive  state,  in  which  con- 
dition it  becomes  worse  than  the 
cast  iron  from  which  it  was  origi- 
nally made.  None  but  a  very  skil- 
ful blacksmith  can  weld  it;  for, 
when  slightly  re-heated,  it  falls  to 
coarse  sandy  pieces,  or  melts  like 
pig  iron.  That  which  thus  loses 
its  fibrous  texture  in  heating,  the 
smith  calls  '  burnt  iron.' 

The  philosophy  of  the  improve- 
ment of  metal  consists  in  the  cir- 
cumstance that  a  part  of  its  impu- 
rities which  are  originally  in  che- 
mical combination,  are  converted 
into  mechanical  admixtures.  Iron 
containing  a  small  amount  of  car- 
bon, silicon,  or  phosphorus,  is  al- 
ways more  hard  and  strong  than 
pure  iron.  Pure  iron  is  quite  soft. 
Impure  iron  has  the  property  of 
crystallizing,  on  being  suddenly 
cooled :  the  size  of  these  crystals 
is  proportional  to  the  amount  of 
carbon  in  chemical  combination 
with  the  iron,  in  proportion  to 
other  matter.  Between  the  crys- 
tals minute  spaces  are  left,  which 
serve  for  the  absorption  of  oxygen. 
By  this  means,  silicon  and  calcium 
may  be  oxidized,  but  not  carbon, 
phosphorus,  and  sulphur.  The 
metal  improves  in  quality  in  pro- 
portion as  oxygen  finds  access  to 
its  impurities. 

The  absolute  cohesion  or  strength 
of  wrought  iron  is  not  dependent 
upon  the  degree  of  purity  of  the 
metal,  but  upon  a  given  mixture  of 
cinder  and  iron.  Pure  iron,  which 
is  always  soft,  may  be  required  for 
various  purposes,  as  in  the  manu- 
facture of  cast  steel ;  but,  in  most 

548  ^~" 


cases,  an  impure  but  fibrous  iron  is ' 
preferable.  In  making  wrought , 
iron,  the  main  difilculty  consists,  < 
not  in  producing  fibres  in  the  first : 
stages  of  the  operation, — ^for  this  [ 
may  be  accomplished  by  almost 
every  experienced  manufacturer, — 
but  in  retaining  these  fibres  through  , 
every  subsequent  stage  of  the  ope- 1 
ration. 

Wrought  iron  of  good  quality  is  | 
silvery  white  and  fibrous ;  carbon  I 
imparts  to  it  a  bluish,  and  often  a 
gray  colour ;  sulphur,  a  dark,  dead 
colour,  without  a  tinge  of  blue ; 
silicon;  phosphorus,  and  carbon,  a 
bright  colour,  which  is  the  more 
beautiful  the  more  the  first  two  i 
elements  preponderate.   The  lustre  • 
of  iron  does  not  depend  principally  I 
upon  its  colour ;  for  pure  iron,  al- . 
though  silvery  white,  reflects  hot 
little  light.    A  small  quantity  of, 
carbon  in  chemical  combination, 
phosphorus,  or  silicon,  increases  its 
brilliancy.   Its  lustre  is  diminished 
by  silex,  carbon  in  mechanical  ad- 
mixture, cinder,  lime,  sulphur,  or , 
magnesia.    Good  iron  should  ap- 
pear fresh,  somewhat  reflex  in  its  i 
fibres,  and  silky.    A  dead  colour  [ 
indicates  a  weak  iron,  even  though  { 
it  is  perfectly  white.     Dark  but 
very  lustrous  iron  is  always  supe- ! 
rior  to  that  which  has  a  bright  co- 1 
lour  and  feeble  lustre.  Coarse  fibres  | 
indicate  a  strong,  but,  if  the  iron  is  ■ 
dark,  an  inferior  article.    Where ' 
the  iron  is  of  a  white,  bright  co- ; 
lour,  th6y  indicate  an   article  of 
superior  quality  for  sheet  iron  and  I 
boiler-plate,  though  too  soft  fdr : 
railroad  iron.    For  the  latter  pur- 1 
pose,  a  coarse,    fibrous,    slightly 
bluish  iron  is  required.     Iron  of  * 
short  fibre  is  too  pure ;  it  is  gene-  j 
rally  hot-short,  and,  when  cold,  not  < 
strong.   This  kind  of  iron  is  apt  to 
result  from  the  application  of  an  j 
excess  of  lime :  its  weakness  is  the 
result  of  the  absence  of  all  impuii-  * 
ties.  The  best  qualities  of  bar  iron 
always  contain  a  small  amount  of  ' 
impurity.     Steel  ceases  to  be  hard  I 


XEB 


YELLOW  OCHRE. 


YEL 


'and  strong,  when  deprived  of  the 
small  amount  of  silicon  it  contains, 
or  if  the  silicon  is  oxidized  by  re- 
peated beating.  This  is  the  case 
with  bar  iron.  If  deprived  'of 
all  foreign  admixtures,  it  ceases  to 
be  a  strong,  tenacious,  and  beauti- 
ful iron,  but  becomes  a  pale,  soft 
metal,  of  feeble  strength  and  lustre. 
Good  bar  or  wrought  iron  is  always 
fibrous:  it  loses  its  fibres  neither 


XEB 

Xebec,  in  navigation,  a  small  three- 
masted  vessel,  without  a  bowsprit, 
principally  used  in  the  Mediter- 
ranean 

Xenodi^ehium,  a  room  in  a  monastery 
for  the  reception  and  entertain- 
ment of  strangers,  pilgrims,  and 
the  relief  of  paupers 

XP,  L,    the  initials   of  the  Greek 


YAC 

Yacht,  ip  navigation,  a  small  ship  for 

carrying  passengers 
Yardi  a  court  enclosed  by  walls  and 
other  buildings;   also  a  measure 
of  3  feet :  a  yard  or  yerd  was  an- 
ciently a  spar  or  rafter  in  a  timber 
roof. 
Yardlandf  a  certain  quantity  of  land, 
called,  in  Saxon,  gyrdlander;   in 
Latin,   virgata   terne :    in    some 
places  it  is  20  acres  of  land,  in 
others  24  or  30 
Yellow  is  the  first  of  the  primary  or 
simple  colours,  nearest  in  relation 
to  and  partaking  most  of  the  nature 
of  the  neutral  white ;  it  is  accord- 
ingly a  most  advancing  colour,  of 
great  power   in   reflecting  light. 
Compounded  with  the  primary  red, 
it  constitutes  the  secondary  orange 
and  its  relatives,  scarlet,  &c.,  and 
other  warm  colours. 
Yellow  Lake.  There  are  several  pig- 
ments of  this  denomination,  vary- 
ing in  colour  and  appearance,  ac- 


hy heat  nor  by  cold.  Time  may 
change  its  aggregate  form ;  but  its 
fibrous  quality  should  always  be 
considered  the  guarantee  of  its 
strength.  Iron  of  good  quality  will 
bear. cold  hammering  to  any  ex- 
tent. A  bar  an  inch  square,  which 
cannot  be  hammered  down  to  a 
quarter  of  an  inch,  on  a  cold  anvil, 
without  showing  any  traces  of  j 
splitting,  is  an  iiiierior  iron. 


XYS 

names  of  Christ ;  a  monogram,  re- 
presented in  paintings  and  mosaics 
by  the  Greek  Christians 

Xyiogrcq^hyt  the  art  of  engraving  on 
wood 

XystoSf  in  ancient  architectore,  a 
large  portico  in  the  gymnasium, 
for  the  accommodation  of  the 
wrestlers ;  a  sheltered  walk 


YEL 

cording  to  the  colouring  substances 
used  and  modes   of  preparation. 
They  are  usually  in  the  form  of 
drops,  and  their  colours   are,  in 
general,  bright  yellow,  very  trans- 
parent, and  not  liable  to  change  in 
an  impure  atmosphere, — qualities 
which  would   render  them  very 
valuable  pigments,  were  they  not 
soon   discoloured  and   even   de- 
stroyed by  the  opposite  influence 
of  oxygen  and  light,  both  in  water 
and  oil,  in  which  latter  vehicle, 
like  other  lakes  in  general,  they 
are  bad  dryers,  and  do  not  stand 
the  action  of  white  lead  or  other 
metallic  colours.    If  used,  there- 
fore, it  should  be  as  simple  as 
possible. 
Yellow   Ochre,  called  also   Mineral 
Yellow,  is  a  native  pigment,  found 
in  most  countries,  and  abundantly 
in  our  own.   It  varies  considerably 
in  constitution  and  colour,  in  which 
latter  particular  it  is  found  from  a 


549 


2a5 


Z£B 


ZIGZAG  MOULDING. 


ZIN 


bright  but  not  Tery  vivid  yellow  to 
abrown  yellow»  called  spruce  ochrci 
and  is  always  of  a  warm  cast.  Its 
natural  variety  is  much  increased 
by  artificial  dressing  and  com- 
pounding. 
Yeliow  Orpimenty  or  Yellow  Artenic^ 
is  a  sulphurate  oxide  of  arsenic,  of 
a  beautiful,  bright,  and  pure  yellow 
colour,  not  extremely  durable  in 
water,  and  less  so  in  oil.  In  tint 
with  white  lead,  it  is  soon  de- 
stroyed. It  is  not  subject  to  dis- 
coloration in  impure  air. 


ZEB 

Zebba  wood  is  the  produce  of  the 
Brazils  and  Rio  Janeiro ;  it  is  sent 
in  logs  and  planks  as  large  as 
24  inches.  The  colour  is  orange 
brown  and  dark  brown  variously 
mixed.  Its  beautiful  appearance 
fits  it  for  cabinet-work  and  turnery. 

2^0^  the  commencement  of  a  scale 
marked  0,  or  nothing.  It  usually 
denotes  the  point  from  which  the 
scale  of  a  thermometer  is  graduated. 

Zeta^  presumed  to  be  a  room  over 
the  porch  of  a  Christian  church 

Zigzag,  a  moulding  by  lines  arranged 
in  the  manner  of  the  heraldic 
chevron.  Zigzag  is  found  fre- 
quently used  in  Norman  and  An- 
glo-Norman architecture.  Very 
many  beautiful  specimens  of  this 
ornament  exist  in  doors  and  win- 
dows of  the  Anglo-Norman  Gothic 
in  England.  (See  Doors,  and  the 
Frontispiece  for  an  early  specimen.) 

Zinc,  This  metal  exists  in  abundance, 
and  is  employed  for  many  pur- 
poses. It  is  commonly  combined 
with  sulphur  in  zinc  blende,  and 
with  carbonic  acid  in  the  mineral 
calamine,  which  is  the  most  valu- 
able of  all  its  ores.  Zinc  may  be 
o^ained  pure  by  re-distilling  in  a 
porcelain  retort,  which  is  sold  in 
commerce.  It  is  obtained  from  the 
ores  A  follows:  they  are  first 
washed  and  mixed  with  powdered 
coke  or  charcoal,  are  distilled  from 

550 


Yew,  The  yew-tree  is  comroon  In 
Spain,  Italy,  and  England,  and  is  in- 
digenous to  Nottinghamshire.  The 
tree  is  not  large,  and  the  wood  is 
*  of  a  pale  yellowish-red  colour,  hand- 
somely  striped,  and  often  dotted 
like  amboyna.  It  has  been  long 
famed  for  the  construction  of  bows, 
and  is  still  so  employed.  The 
English  species  is  a  hu-d,  tough, 
and  durable  wood,  and  lives  to  a 
great  age.  It  is  also  used  for  the 
making  of  chairs,  the  handles  of 
articles  of  furniture,  &c. 


ZIN 

an  earthen  close  vessel,  with  an 
iron  tubepassing  through  its  bottom, 
the  upper  end  of  which  is  open,  and 
the  lower  end  entering  a  vessel  of 
water.  At  a  bright  red  heat  zinc 
volatilizes,  and  is  condensed  in  the 
water,  gases  passing  ofiT  along  vrith 
it.  It  is  a  bluish -white  metal, 
which  slowly  tamisfaes  in  the  air. 
It  is  brittle  at  ordinary  tempera- 
tures, but  at  about  300°  it  is  mal- 
leable, and  may  be  rolled  or  ham- 
mered into  sheets,  and  retains  its 
ductility  when  cold.  At  400**  it 
may  be  reduced  to  powder:  it 
melts  at  773^ 
Zinc  white  is  an  oxide  of  zinc  which 
has  been  more  celebrated  as  a  pig- 
ment than  used,  being  jierfecthr 
durable  in  water  and  oil,  but  want> 
ing  the  body  and  brightness  of  fine 
white  leads  in  oil ;  while,  in  water, 
constant  or  barytic  white  and  pearl 
white  are  superior  to  it  in  colour, 
and  equal  in  durability.  Never- 
theless, zinc  white  is  valuable  as 
far  as  its  powers  extend  in  painting, 
on  account  of  its  durability  both  in 
oil  and  water,  and  its  innocence 
with  regard  to  health ;  and,  when 
duly  and  skilfully  prepared,  the  co- 
lour and  body  of  this  pigment  are 
sufficient  to  qualify  it  for  a  generd 
use  upon  the  palette,  although  the 
pure  white  of  lead  most  merit  a 
preference  in  oil. 


£LE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


el; 


ZoclBt  A  name  given  to  a  low,  plain, 
•  square  member  or  plinth  support- 
ing a  column 

Zoopkoru8f  in  architecture,  a  part 
between  the  architraves  and  cor- 
nice, 80  called  on  account  of  the 


ornaments  carved  on  it,  amoni 
which  are  the  figures  of  animals 
Zyghyr,  or  Siggery  in  mining.  Whet 
a  slow  stream  of  water  issues 
through  a  cranny,  it  is  said  to 
sigger,  or  zyghyr. 


ADDENDA. 


Angx.ib*staffs  or  5'/q^-^a<2f,  vertical 
heads,  generally  of  wood,  fixed  to 
exterior  angles  of  a  bmlding,  flush 
with  the  surface  of  the  plaster, 
on  both  sides,  for  the  purpose  of 
fortifying  them  against  accident. 
They  serve  also  for  floating  the 
plaster.  Their  section  is  about 
three-fourths  of  a  circle,  with  a 
projecting  part  from  the  other 
quarters,  by  which  they  are  fast- 
ened to  the  wood-bricks,  plugging 
or  bond  timber. 

Angular  modillioTU,  those  which  are 
placed  at  the  return  of  a  cornice 
in  the  diagonal  vertical  plane,  pass- 
ing through  the  angle  or  mitre  of 
the  cornice 

Electric  Telegraph.  The  employment 
of  electricity  in  the  transmission  of 
intelligence  originated  at  an  early 
period  of  the  history  of  electric^ 
science.  Plans  to  this  effect  had 
been  brought  before  the  public; 
but  all  wanted  a  simplicity  of  prin- 
ciple and  of  construction.  In 
1837,  Messrs.  Cooke  and  Wheat- 
stone  obtained  their  first  patent  for 
an  electric  telegraph,  applicable  to 
general  purposes.  This  patent  has 
been  subsequently  followed  at  short 
intervals  by  others,  in  which  the 
invention  has  been  gradually 
brought  to  its  present  form ;  the 
principles  originally  employed  have 
been  progressively  rendered  more 
varied  and  general  in  their  ap- 
plication, and  the  apparatus  more 
simple  in  its  details.  By  these 
improvements  the  number  of  wires 
necessary  for  the  conveyance  of 
intelligence  has  been  reduced,  and 
the  construction  has  been  rendered 
cheaper  and  more  perfect. 
The  electric  telegraph  involves 

551 


in  its  construction  two  essential 
principles.  First,  that  a  magnetized 
needle,  which  is  free  to  rotate 
about  its  centre,  being  brought 
near  to.  a  wire,  through  which  an 
electric  current  is  passing,  has  a 
tendency  to  place  itself  at  right 
angles  to  that  vrire ;  the  direction 
of  its  motion  following  a  certain 
invariable  law.  This  fact  was  the 
discovery  of  Prof.  (Ersted,  of  Co-  I 
penhagen,  in  1819.  Secondly,  that 
a  piece  of  soft  iron,  not  being  per- 
manently magnetic,  is  rendered 
temporarily  so,  during  the  trans- 
mission of  an  electric  current  along 
a  wire  coiled  spirally  around  it. 

The  figures  to  which  reference 
is  here  made,  in  the  brief  deiscrip- 
tion  of  the  apparatus,  are,  1.  A 
view  of  the  interior  of  the  single- 
needle  instrument,  showing  the 
position  of  the  coil  and  H  the 
battery  connections.  2.  A  vertical 
section  of  the  same,  through  the 
coil  and  handle.  3.  The  handle  | 
or  key,  in  the  position  for  giving  a  \ 
signal,  part  being  removed,  to  ren-  1 
der  the  battery  connections  more 
distinct.  4.  Plan  of  the  same.  The 
double -needle  instrument  differs 
from  the  single-needle  only  in  the 
duplication  of  all  the  parts. 

The  coil  a,  figs.  1  and  2,  consists 
of  a  light  hollow  frame  of  brass  or 
wood,  around  which  are  wound,  in 
two  portions,  about  200  yards  of 
fine  copper  wire,  covered  vrith  silk 
or  cotton.     This  length  of  wire 
renders  the  indications  of  the  nee- 
dle distinct  and  prompt,  even  with 
a  low-battery  power,  or  when  form- 
ing part  of  a  very  extended  circuit. 
The  resistance  which  would  be  of- 
fered by  the  fine  wire  of  the  coil 


J 


ELB  ADDENDA  {ELECTRIC  TELEGRAPH).  ELK 


ELE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


(its  diameter  being  about  y^th  of 
an  inch)  to  the  passage  of  a  current 
of  electricity,  derived  from  an  or- 
dinary battery  of  a  few  cells  only, 
is  overcome  by  using  a  battery  ar- 
rangement of  considerable  inten- 
sity, but  which  develops  the  elec- 
trical fluid  only  in  small  quantity. 
Or,  speaking  rather  more  correctly, 
we  should  say,  that  the  electro- 
motive resistance,  both  of  the  bat- 
tery and  also  of  the  ordinary  circuit, 
being  very  considerable,  the  intro- 
duction of  the  resistance  of  the 
coil  into  the  latter  produces  but 
little  influence  upon  the  transmis- 
sion of  the  current.     Within  the 
brass  frame,  and  therefore  interior 
to  the  coils  of  wire,  is  suspended  a 
magnetic  needle,  upon  a  horizontal 
axis   b,  which  passes  across  the 
middle  of  the  frame,  and  turns  on 
fine  pivots  at  the  back  and  front  of 
the  coil.    In  front  of  the  frame  and 
of  the  dial  of  the  instrument  is 
fixed  on  the  same  axis  6,  a  second 
needle  having  its  poles  oppositely 
placed  to  those  of  the  first.    This 
outer  needle  serves  as  the  indicator 
or  pointer,  by  which  the  signals 
are  made,  and  at  the  same  time  is 
acted  upon  by  the  coil,  though  in 
a  less  degree  than  the  inner  needle. 
The  combination  of  the  two  needles 
being  thus  rendered  astatic,  it  is 
necessary  to  give  a  slight  prepon- 
derance to  their  lower  ends,  in  or- 
der that  they  may  recover  theu* 
vertical  position,  after  having  been 
deflected;  and  the  action  of  gravity 
has  been  found  more  effectual,  in 
bringing  the  needle  to  rest  without 
oscillations,  than  either  springs  ap- 
plied at  the  sides,  or  the  directive 
influence  of  permanent  magnets. 
With  the  coil  and  needles  thus  ar- 
ranged, it  is  evident  that  signals 
may  be  given  by  the  combination 
of  successive  deflections  to  one  side 
or  the  other;  the  extent  of  such 
deflections  being  limited  to  any 
degree  that  may  be  found  con- 
venient, either  by  pins  fixed  on  the 
dial  of  the  instrument,  or  by  stops 

553 


placed  at  the  sides  of  the  brass 
frame  of  the  coil.  In  fact,  all  that 
is  necessary  for  rendering  these 
movements  of  the  needle  available 
for  the  transmission  of  intelligence, 
is  a  contrivance  for  reversing  with 
ease  and  rapidity  the  connection  of 
the  battery  with  the  ends  of  the 
two  conducting  wires.  This  expe- 
dient is  provided  by  the  handle  or 
key  of  the  instrument. 

The  conductor  through  which 
the  electrical  current  is  to  circulate 
must  be  absolutely  complete  in  all 
parts.  It  is  not  necessary  that  the 
material  of  the  circuit  be  the  same 
throughout,  but  only  that  its  con- 
ductibility  be  maintained  from  the 
one  pole  of  the  battery  to  the 
other ;  the  slightest  want  of  con- 
tinuity of  the  conducting  matter, 
at  any  part  of  the  circuit,  being 
fatal  to  the  passage  of  the  fluid. 
So  long  as  the  wires  for  telegra- 
phic purposes  were  extended  be- 
tween the  two  points  of  communi- 
cation, by  being  laid  within  tubes 
buried  in  the  earth,  a  second  wire 
was  requisite  to  enable  the  current 
to  return  from  the  distant  station 
to  the  point  whence  it  set  out.  It 
was  well  known  that  the  earth 
itself  afforded  such  a  means  of 
return ;  but  the  insulation  of  the 
wires  in  the  tubes  from  the  earth, 
could  not  be  rendered  sufficiently 
perfect,  to  make  the  use  of  the 
earth,  as  a  portion  of  the  circuit, 
either  prudent  or  desirable.  When, 
however,  the  vdres  were  suspended 
in  the  air,  according  to  Mr.  Cooke's 
patent  of  1842,  the  earth  was  ad- 
vantageously employed  as  half  the 
circuit.  All  that  was  found  neces- 
sary, was  to  connect  the  extreme 
ends  of  the  conducting  wire  with 
plates  of  copper  or  other  metal  of 
two  or  three  feet  of  surface,  buried 
at  some  depth  in  the  ground ;  or 
with  any  system  of  gas  or  water- 
pipes,  which  might  afford  a  con- 
tinuous metallic  path  for  the  fluid 
to  the  earth.  In  either  case,  the 
depth  of  the  connection  heneath 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


ADDENDA  (ELECTRIC  TELEGRAPH)* 


ELE 


the  surface  must  be  sufficient  to 
insure  certain  contact  with  moist 
earth    or   with    water,    provided 
that  this  latter  be  not  confined 
within   any  cistern  or  reservoir. 
When  all  these  precautions  have 
been  taken,  the  passage  of  electri- 
city is  readily  effectedi  the  earth 
appearing  io  offer  little  or  no  re- 
sistance to  its  progress.    Accord- 
ing to  the  law  established  by  Ohm, 
the  resistance  of  igiy  conductor 
varies  directly  as  its  length,  and  in- 
versely as  its  sectional  area.    The 
earth  may  evidently  be  regarded 
as  a  conductor,  of  which  the  dia- 
Ineter  is  infinite,  compared  with  its 
length,  and  we  might  therefore  be 
led  to  expect  the  result  mentioned 
above. 

To  return,  however,  to  the  de- 
scription of  the  apparatus,  the  key 
or  handle  by  means  of  which  the 
connection  of  the  battery  is  effected 
and  varied,  consists  of  a  cylinder, 
in  which  is  a  middle  zone,  .e,  of 
hard  wood  or  iVory,  while  the  ends 
are  of  metal.  &ne  of  these  ends,  c, 
extending  through    the    case  in 
front,  forms  the    actual  handle; 
while  the  other,  <f,  is  turned  down 
to  a  shoulder  and  forms  a  pivot, 
which  rests  in  a  brass  collar,  p. 
The  end  d  carries  a  steel  pin,/, 
projecting  upward,  and  c,  a  similar 
pin  g,  directed  downward.     The 
battery  being  connected  with  the 
terminals  z  and  c,  and  thence  by 
the  brass  strips  k  and  m,  of  which 
the  extremities  rest  as  springs  on 
the  metallic  ends  of  the  cylinder, 
may  in  fact  be  considered  as  having 
its  poles  at  the  two  pins,/ and  g^ 
which  are  fixed  in  those  ends.  Two 
springs,  A  and  h\  are  fixed  by 
broad  feet  to  the  base  of  the  in- 
strument, and  rest  by  their  upper 
extremities  on  two  studs  or  points 
projecting  from    a  brass  rod,  «, 
screwed  into   the  case  in  front. 
These  springs  form  the  circuit  be- 
tween the  terminal  /I,  with  which 
one  end  of  the  conducting  wire  is 
connected,  and  /  4.    Between  this 

555 


latter  terminal  and  the  external 
connection,  /  2,  the  coil  itself,  and 
the  brass  strip  extending  from  IZ 
to  /2,  are  interposed.     When  a 
signal  is  being  sent  through  the 
instrument  (supposed  to  hold  the 
place  of  No.  2  in  fig.  5),  the  cur- 
rent from  No.  1  being  considered 
to  enter  from  the  loag  wire  on  the 
line,  by  the  terminal  /  2,  passes 
along  the  brass  strip  to  the  terminal 
/  3,  thence  through  the  coil  to  /4 ; 
then  to  the  spring  A,  across  the 
pin  t,  down  the  spring  V,  and  to 
the  terminal  f  1  in  connection  with 
the  wire  leaving  the  station.  Were 
the  instrument  in  question  situated 
as  No.  1  or  No.  3,  it  will  be  seen 
that  one  of  the  terminals,  II  ox  12, 
according  to  its  position,  would  be 
joined  to  the  wire  coming  from  the 
earth-plate. 

When  a  signal  is  to  be  given  by 
the  instrument,  the  handle  bemg 
turned,  as  in  figs.  3  and  4,  one 
battery-pin,  /,  is  brought  in  con- 
tact with  the  spring  h\  which  is 
bent  back  and  released  from  its 
contact  with  i,  while  the  other 
battery-pin  ^,  is  pressed  against  the 
foot  of  the  other  spring  A,  which  at 
this  part  is  turned  up  to  act  as  a 
stop.  The  current  being  then  sup- 
posed to  start  from  the  pole/,  pro- 
ceeds down  the  spring  A',  to  the 
coil  and  terminal  /  2,  as  before ; 
thence  along  the  line  through  the 
other  instruments,  and  into  the 
earth  at  the  further  extremity  of 
the  line.  Re-ascending  from  the 
earth  by  the  vrire  connected  vrith 
the  terminal  /I,  it^gains  the  foot 
of  the  spring  A,  with  which  the 
second  battery  pole  g,  is  in  con- 
tact. It  will  be  seen  that  the 
direction  of  the  current  is  (Afferent, 
according  as  the  key  is  turned  to 
the  right  or  left.  The  position  of 
the  battery  wires  is  such,  that  the 
needle  shall  be  deflected  in  paral- 
lelism to  the  handle.  A  comparison 
of  fig.  5,  in  which  three  instruments 
are  shown  in  series,  with  the 
figures  1,  2,  -3,  and  4,  will  render 


ELE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


the  method  of  connection,  both  of 
the  two  tenninal  and  of  the  inter- 
mediate instruments,  sufficiently 
obvious.  The  wires  on  entering  a 
station  are  designated  as  *up'  or 
*down'  wires,  according  to  the 
portion  of  the  Une  from  which  they 
come.  Care  must  be,  of  course, 
taken  that  all  the  instruments  in 
one  series  are  similarly  joined  to 
the  up  and  down  wires,  so  that  the 
course  of  the  current  may  be  alike 
in  all.  At  the  extreme  *  up  station' 
the  earth  connection  becomes  the 

*  up  wire,'  and  at  the  opposite  ter- 
minus it  takes  the  place  of  the 

*  down  wire.* 

The  electric  fluid  is  represented 
as  starting  from  one  pole  of  the  bat- 
tery only,  and,  after  traversing  the 
circuit,  returning  to  the  other  pole. 
It  is,  however,  more  consonant 
with  the  theories  deduced  from 
the  observation  of  electrical  phe- 
nomena, to  suppose  that  force  is 
developed  equsdiy  at  both  poles  of 
the  battery. 

The  second  principle  is  that  of 
the  temporary  magnetization  of 
soft  iron  by  the  electric  current, 
applied  for  the  purpose  of  sounding 
an  alarum  at  a  distant  station,  in 
order  to  summon  the  attendant  to 
his  instrument.  The  same  princi- 
ple has  been  employed  from  an 
early  period  of  the  invention,  both 
by  Mr.  Cooke  and  by  Prof.  Wheat- 
stone,  to  transmit  visible  signals  by 
causing  the  rotation  of  a  disc, 
bearing  letters  or  figures,  or  of  a 
hand  or  index  pointing  to  charac- 
ters on  a  fixed  dial ;  but  in  Eng- 
land the  needle  telegraph  has  been 
universally  adopted,  in  preference 
to  any  other  form.  Many  improve- 
ments have,  however,  been  effected 
within  the  last  few  years  by  Prof. 
Wheatstone  in  the  construction  of 
the  mechanical  telegraph,  as  it  has 
been  named  in  contradistinction  to 
the  needle  instrument.  The  same 
gentleman  has  also  succeeded  in 
substituting  for  the  voltaic  battery 
in  the  working  of  this  telegraph, 


the  magneto-electric  machine,  in 
which  the  current  is  derived  by 
induction  from  a  permanent  mag- 
net. The  improvement  which  was 
efifected  by  this  adoption  of  a  source 
of  power,  alike  energetic  and  un- 
alterable, will  be  immediately  per- 
ceived. Telegraphs  on  this  plan  of 
construction  have  been  erected  in 
Prussia  and  France,  and,  were  it 
not  for  some  very  marked  advan- 
tages connected  with  the  use  of 
the  needle  signals,  they  could 
hardly  fail  to  become  general. 

The  ringing  of  the  alarum  was 
originally  effected  by  the  direct 
action  of  the  voltaic  magnet  upon 
the  hammer  of  the  bell ;  but  this 
method  has  been  long  superseded. 
The  apparatus  generally  in  use  for 
this  purpose  is  shown  in  a  front 
and  back  view. in  figs.  11  and  13, 
and  in  a  side  view  at  figure  12. 
An  electro-magnet  is  formed  by 
coiling  fine  insulated  copper  wire 
around  two  cylinders  of  very  soft 
pure  iron.  These  coils,  c  c,  are 
then  connected  by  two  of  their 
ends,  in  such  a  manner  that  the 
direction  in  which  the  wire  is 
wound  about  the  iron  cores  may 
be  alike  in  both.  The  iron  cylin- 
ders are  joined  together  at  one  end 
by  a  cross-piece  df  likewise  of  soft 
iron,  so  that  the  whole  then  forms 
a  horse-shoe  magnet,  having  how- 
ever its  two  sides  parallel.  In  front 
of  the  free  ends  or  poles  of  this 
magnet,  which  is  fixed  on  the  top 
of  the  plates  of  the  alarum,  an  arm- 
ature a,  of  soft  iron,  is  placed  at 
such  a  distance  that  it  may  be 
strongly  attracted  by  the  electro- 
magnet when  the  circuit  is  com- 
pleted through  its  coils.  The  arm- 
ature moves  on  an  arbor,  upon 
which  a  detent  or  catch  e,  is  fast- 
ened, and  so  arranged  that  it  is 
disengaged  from  a  small  fly  ©, when- 
ever the  attraction  takes  place. 
This  disengagement  allows  a  train 
of  clock-work,  impelled  by  a  spring 
or  weight,  to  run  down,  and  by  the 
action  of  a  scape-wheel  and  pal- 


557 


ADDENDA  (ELECTRIC  TELEGRAPH). 


CAMBHtDQE. 


CLE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


lets,  seen  in  fig.  11,  a  hammer,  A, 
rapidly  strikes  a  small  bell  g.  Im- 
mediately, however,  that  the  cur- 
rent ceases  to  flow  through  the 
coiU,  the  iron  within  them  loses 
its  magnetism,  a  small  re-acting 
spring,  8f  draws  back  the  armature, 
and  interposes  the  detent  so  as  to 
stop  the  clock-work.  It  is  neces- 
sary that  the  iron  of  the  magnet 
should  be  quite  pure  and  soft,  as 
otherwise  the  magnetization  is  to 
a  greater  or  less  degree  permanent ; 
and  this  may  be  the  case  to  such 
an  extent  as  to  keep  the  armature 
attracted,  even  after  the  cessation 
of  the  electric  current.  The  bell 
would  then  continue  to  ring  until 
the  disengagement  of  the  armature 
were  caused  by  the  hand  of  the 
attendant. 

The  bell  or  alarum  may  form 
part  of  the  telegraphic  system  in 
two  modes.  In  the  first,  and  most 
economical,  its  coil  is  made  to  form 
part  of  the  circuit  of  one  of  the 
needle  wires,  in  conjunction  with 
a  key  or  rheotome.  In  the  second 
and  more  complete  method  of  in- 
troducing the  alarum,  a  distinct 
wire  is  employed  for  it,  in  the 
course  of  which  the  magnet  coils 
at  the  several  stations  are  inter- 
posed. A  key  of  different  con- 
struction (shown  in  section  at  fig. 
14)  is  then  employed.  The  body 
is  of  brass,  but  two  stout  wires,  z 
and  c,  are  conducted  through  ivory 
tubes,  and  terminated  in  studs,  j9/7, 
at  the  top  and  bottom  of  the  cylin- 
drical end  of  the  key;  the  wires 
and  studs  being  insulated  from  each 
other,  and  from  the  key,  by  the 
ivory  in  which  they  are  fixed.  The 
collar,  if,  and  nut,  t,  serve  to  se- 
cure the  key  to  the  side  of  the  case 
or  box  in  which  it  is  placed,  the 
former,  f,  also  containing  the 
spring,  by  which,  after  use,  the 
key  is  brought  back  to  its  quiescent 
position.  Two  springs,  not  shown 
in  the  figure,  then  rest  against  the 
metal  of  the  end,  one  on  each  side, 
and  while  in  this  position,  merely 

"559 


complete,  by  the  intervening  metal, 
the  circuit  of  the  bell- wire  which  is 
connected  to  the  foot  of  one  spring 
directly,  and  to  the  foot  of  the 
other  by  the  intervention  of  the 
bell  coiL  The  wires,  z  and  c,  are 
joined  to  the  two  poles  of  the  bat- 
tery by  pieces  of  thin  wire,  which 
will  offer  no  resistance  to  the  revo- 
lution of  the  key  on  its  axis.  In 
the  quiescent  position,  the  course 
of  a  current  entering  from  a  distant 
station  would  be,  from  the  line- 
wire  on  one  side,  along  one  spring, 
across  the  body  of  the  key  to  the 
other  spring,  and  thence  through 
the  alarum  coil  to  the  continuation 
of  the  line -wire,  or  to  the  earth 
connection.  When,  however,  the 
bell  is  to  be  rung  to  call  the  atten- 
tion of  the  clerk  at  another  station, 
the  key  is  for  a  moment  turned  one- 
quarter  round.  This  brings  the 
battery  studs,  pp,  into  the  circuit, 
instead  of  the  body  of  the  key ; 
and  the  current  then  proceeds  from 
the  battery  of  the  ringing  station 
by  the  spring  and  wire  on  one  side, 
passes  along  the  line,  and  returns 
by  the  earth  through  the  other 
spring  again  to  the  battery. 

The  relative  advantages  of  these 
two  methods  may  be  briefly  stated. 
The  first  has  the  recommendation 
of  economy,  inasmuch  as  no  addi- 
tional vrire  is  necessary  for  the 
bell.    If,  however,  the  clerk  in 
charge    of   an    instrument,  after 
turning  off  his  bell  preparatory  to 
sending    or    transmitting    intelli- 
gence, should  chance  to  leave  his 
telegraph,  and  omit  to  turn  the 
key  so  as  to  replace  the  bell  in  the 
circuit,  no  means  are  left  to  other 
stations  of  calling  his  attention, 
except  by  working  the   needles, 
with  the  chance  of  their  movement 
meeting  his  eye.    By  the  adoption 
of  the  second  method,  the  expense 
of  an  additional  wire  is  incurred, 
but  the  bells  at  all  stations  are 
constantly  in  a  position  to  be  rung 
if  necessary.     In  addition  to  this, 
it  may  be  remarked,  that  by  keep- 


ELE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


EL! 


ing  the  bell  and  needles  distinct 
from  each  other,  no  derangement 
of  the  one  is  to  be  feared  from 
injury  to  or  derangement  in  the 
other. 

Mr.  Cooke's  first  plan,  in  the 
extension  of  the  conducting  wires 
between  distant  points,  was,  as  has 
been  already  stated,  to  cover  each 
wire  with  cotton  or  silk,  and  then 
with  pitch,  caoutchouc,  resin,  or 
other  non-conducting  material,  and 
to  enclose  them,  thus  protected,  in 
tubes  or  pipes  of  wood,  iron,  or 
earthenware.  Excepting  in  those 
localities  where  the  suspension  of 
wires  is  impracticable,  as  in  streets, 
towns,  or  on  public  roads,  the  early 
plan  has  given  place  to  more  re- 
cent inventions.  In  1842,  a  patent 
was  obtained  by  Mr.  Cooke,  for  a 
means  of  suspending  and  insulating 
the  wires  in  the  air,  and  the  me- 
thod described  in  his  specification 
has  been  since  adhered  to,  with 
little  variation.  The  wires  are 
generally  of  iron,  which  is  galva- 
nized, to  protect  it  from  the  action 
of  the  atmosphere.  They  are  of 
about  one -sixth  of  an  inch  in  dia- 
meter, corresponding  to  No.  8  of 
the  wire-gauge.  Being  obtained 
in  as  great  lengths  as  possible,  in 
the  first  place,  successive  pieces 
are  welded  together,  until  a  coil  of 
about  440  yards  is  formed.  These 
rings  or  bundles  weigh  about  120 
pounds  each.  The  wires  are  sus- 
pended on  the  line,  from  stout 
squared  posts  or  standards,  of 
Dantzic  or  Memel  timber.  At 
each  quarter-mile,  a  stronger  post 
is  fixed,  from  which  the  succeeding 
lengths  of  wire  on  either  side  are 
strained  or  tightened  up.  Inter- 
mediate to  these  principal  posts, 
are  placed  smaller  standards  at 
from  45  to  55  yards  asunder,  for 
the  purpose  of  supporting  the  wires. 
The  straining  apparatus  is  very 
simple  consisting  merely  of  a  reel 
or  pulley,  turning  between  two 
cheeks  of  cast  iron,  and  carrying 
upon  its  axis  a  ratchet-wheel,  into 

560 


the  teeth  of  which  a  click  or  catcl 
falls.  These  winding  heads,  showi 
"Etrr,  figs.  7  and  9,  are  connectec 
through  the   post  by  a    bolt  o; 
wrought  iron  b,  tapped  into  eacb 
head.     This  bolt  not  only  bean 
the  strain  of  the  wires,  but  alsc 
forms  the  metallic  communication 
between  their  ends  wound  on  the 
two>  reels.     In  order  to  insulate 
the  bolt  from  the  wood  of  the  post, 
the  hole  in  this  latt«r  is  bored  very 
large,  and  collars  of  eathenware, 
//,  are  inserted  at  each  side,  in 
which  the  bolt  rests,  and  against 
their  outer  surfaces  th*e  winding 
heads  are  screwed  up  tight.  Fig.  9 
is  a  section  through  the  post  and 
collar,  showing  this  arrangement. 
Fig.  7  is  a  front,  and  8  a  side  view 
of  the  head  of  a  straining  or  quarter- 
post.       The    wires    are    usually 
arranged  in  two  vertical  planes,  at 
the  back  and  front  of  the  standards, 
or  intermediate  posts.    They  are 
not  strained  at  each  quarter-mile, 
but  at  intervals  of  hailf  a  mile  al- 
ternately ;  those  in  the  front  plane 
at  one  post,  and  those  in  the  back 
plane  at  the  next.    The  standards 
or  supporting  posts  have  merely  to 
sustain  the  weight  of  the  wires 
without  relation  to  their  tension. 
They  have  on  each  side  two  stout 
arms  of  oak  or  ash,  secured  by 
bolts,    passing  from   one  to  the 
other,  and  resting  in  collars  of 
earthenware,  xxf  where  they  pass 
through  the  standard.     The  wires 
pass  through  pieces  of  earthen- 
ware, of  a  double  cone  shape,  e  e, 
fastened  to  the  outside  of  the  arms 
by  staples  or  clips,  having  a  nut 
and  screw  at  the  end.  These  staples 
embrace  the  cones  at  a  groove 
in  the  middle  of  their  length.    An 
arm  similar  to  .those  on  the  stand- 
ards is  fixed  to  the  back  and  front 
of  each  post  alternately,  to  support 
that  plane  of  wires  which  passes 
without  being  strained.    The  in- 
sulating earthenwares  between  the 
arm  and  post,  y  y,  are,  however, 
different  in  shape  from  those  used 


SLE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


with  the  standard  arms,  as  greater 
length  is  requisite.    The  following 


are  the  principal  dimensions  of  the 
posts  and  poles  : 


LENGTH. 

AT   BASK. 

AT  TOP. 

\ 

Posts. 

Standards. 

Posts.       1    Standards. 

ft. 

18 
22 
28 

in.           in. 
9x8 

10  X      8 

11  X    10 

in.         in. 
6x6 
7x6 
8x7 

in.         in. 
7    X    ^ 

do. 
do. 

iti.          in. 

do. 
do. 

"\ 

Por  intermediate  lengths  the 
dimensions  are  varied  propor- 
tionally^ In  passing  through  tun- 
nels, or  along  the  faces  of  walls  or 
buildings,  where  posts  cannot  be 
conveniently  fixed  in  the  ground, 
the  wires  are  supported  on  octago- 
nal standards  of  oak  or  ash,  which 
are  fixed  at  about  six  inches  from 
the  wall  by  holdfasts  of  galvanized 
iron.  These  standards  are  about 
two  inches  in  diameter  and  three 
feet  in  length,  being  at  the  top  and 
bottom  turned  down  to  a  shoulder, 
so  as  to  fit  into  a  ring  at  the  ends 
of  the  holdfasts.  The  same  me- 
thod is  adopted  where  the  wires 
have  to  pass  under  bridges  or 
archways. 

The  batteries  employed  are  of  a 
somewhat  peculiar  construction ; 
they  are  made  in  the  form  of  a 
WoUaston's  trough,  in  which  are 
arranged  plates  of  copper  and 
amalgamated  zinc,  each  cell  being 
then  filled  with  dry  and  perfectly 
clean  sand.  When  about  to  be 
used,  the  sand  is  just  moistened 
with  dilute  sulphuric  acid.  These 
batteries  are  singularly  constant, 
having  been  known  to  remain  in 
action  during  a  period  of  from  two 
to  five  months,  with  only  the  occa- 
sional addition  of  a  little  more  acid 
solution,  to  supply  the  waste  by 
evaporation  and  saturation.  The 
effect  of  the  sand  appears  to  be, 
the  prevention  of  too  rapid  an  ac- 
tion, and,  at  the  same  time,  the 
separation  of  the  sulphates  of  cop- 
per and  zinc.     No  copper  is  there- 

561 


fore  deposited  on  the  zinc  plate 
to  the  destruction  of  this  latter  by 
local    action.       The    only   points 
necessary  to  be  observed,  are  the 
perfect  amalgamation  of  the  zinc 
plates,  the  absolute  freedom  of  the 
sand  from  lime   or  other  alkali, 
from  carbonates  or  muriates,  and 
the  purity  of  the  sulphuric  acid. 
The  zinc  is  formed  in  rolled  plates 
of  about  ^  or  -^  of  an  inch   in 
thickness,  and  is  cut  into  pieces  of 
4^    inches    by  3  inches.    These 
plates  will  last  with  care  for  five 
or  six  months  in  almost  constant 
action.    A .  battery  series  of  from 
12  to  60  pairs  is  required,  according 
to  the  length  and  nature  of  the 
line  and  the  number  of  instru- 
ments  in  connection. 

Six  wires  are  extended  along  the 
whole  length  of  railway,  of  which 
the  upper  pair  are  used  with  a  spe- 
cial  double-needle  instrument,  for 
verbal  communication,  between 
the  main  stations,  which  are  Nor- 
wich, Brundall,  Reedham,  ahd  Yar- 
mouth.  Each  of  the  other  four 
wires  includes  at  every  station  a 
coil  and  single  needle.  On  the 
dials  connected  with  the  first  wire 
of  these  four,  is  engraved  the  name 
Norwich  at  all  the  stations;  with 
the  second,  that  of  Brundall,  vrith 
the  third  Reedham,  and  with  the 
fourth  Yarmouth.  Th^  distinct 
telegraphic  system  belonging  to 
each  station  has,  therefore,  its  re- 
presentative at  all  the  other  sta- 
tions. Each  needle  or  pointer  re- 
presents the  state  of  the  portion  of 


ELB 


ADDENDA  (RENAISSANCE). 


jm 


line  under  the  control  of  the  sta- 
tion the  name  of  which  it  hears. 
The  alaram  of  each  instrument  is 
connected  only  with  the  wire  of 
its  own  station,  so  that  on  moving 
either  of  the  needles,  the  alarum 
will  he  rung  at  the  place  corre- 
sponding to  the  name  of  the  needle, 
hut  at  no  other  point,  although  the 
movement  of  the  pointer  will  be 
visible  throughout. 

The  electric  telegraph  is  now 
the  chief  mode  of  transmitting  all 
.  the  news  of  the  Government,  and 
the  important  correspondence  of 
merchants  and  of  the  public  gene- 
rally. Its  influence  has  been  al- 
ready felt  by  the  press.  The  jour- 
nals of  the  large  towns,  which  were 
taken  in  the  country  on  account  of 
their  giving  the  most  recent  news, 
have  lost  a  great  number  of  their 
subscribers ;  whilst  there  has  been 
a  very  large  increase  in  the  cir- 
culation of  the  journals  of  the 
small  towns  near  the  extreme  points 
of  the  electric  telegraphs. 
Renaissancey  that  style  which  arose 
in  all  the  arts  of  design,  from  the 
introduction  of  antique  features, 
consequent  on  the  revival  of  classi- 
cal learning,  and  the  admiration  of 
every  thing  classical  after  the  fall  of 
the  Gothic  system. 

In  Italy,  where  the  arts  had 
never  become  thoroughly  Gothic, 
the  system  so  called  having  been 
an  exotic  never  quite  naturalized  in 
that  country,  the  renaissance  of 
classical  principles  of  taste  com- 
menced  as  early  as  the  13th  century ; 
but  in  the  rest  of  Europe  the 
Crothic  had  then  hardly  arrived  at 
its  complete  development,  or,  if 
become  a  pure  and  consistent  sys- 
tem, had  hardly  begun  to  display 
its  luxuriance ;  and  two  centuries 
at  least  were  required  to  explpre 
its  vast  capabilities,  to  work  out 
its  resources  in  all  their  wondrous 
variety,  and  to  push  on  its  sugges- 
tions beyond  the  limits  of  truth, 
and  advance  so  far  in  complication 
<>nd  absurdity,  as  to  render  a  change 


of  style  necessary;  and  accordingly 
the  arts  of  Germany,  the  Nether- 
lands, France,  and  England,  were 
not  ripe  for  this  change,  called  the 
*  renaissance,'  till  the  end  of  the 
15th  or  beginning  of  the  16th  cen- 
tury ;  «.  e,  not  till  after  the  inven- 
tion of  printing ;  the  great  change 
of  society  resulting  from  which 
invention,  rendered  the  introdac- 
tion  of  the  (already  renovated) 
classic  taste  into  these  countries  t 
very  easy  and  rapid  transition, 
totally  different  from  the  slov 
process  of  renaissance  and  purifi- 
cation, by  which  this  tttte  had, 
in  Italy,  gradually  acquired  con- 
sistency. 

In  architecture    (the   only  art 
here  alluded  to)  the  renaissance  of 
classical  forms  and  principles  first 
distinctly  shows  itself  in  the  works 
of  Brunelleschi,  the  great  Floren- 
tine   architect,   who    lived   from 
1375  to  1444.    His  most  famous 
work,  the  cupola  of  the  cathedral, 
exhibits  a  bold  emancipation  from 
Gothic  complexity,  and  return  to 
classic     simplicity,    without    the 
affectation  of  copying  classic  de- 
tails, which  could  only  be  abused 
and  misapplied  in  a  work  so  totally 
unlike  in  principles  of  construction 
to  those  of  the  ancients.      His ' 
churches   of  S.  Lorenzo    and  S.  i 
Spirito,  though   retaining  Gothic 
plans    and    Byzanto-Gothic   con- 
struction, present  a  still  more  clas- 
sic treatment,  not  only  in  general 
design,  but  in  that  of  details.  The 
little  octagonal  chapel  degH  Jngeli 
is  as  classic  as  any  work  of  the 
ancient    Romans,   and   the  Pi//> 
palace  offers  the  first  example  of 
that  eminently  common-sense  sys- , 
tern  of  palatial  architecture  which 
continued  to  characterize  the  school 
of  Florence  throughout  its  career,  j 
Contemporary  with  this  great  man 
were  Michelozzo,  and  L.  B.  Alberti.  I 
the  first  modem  writer  on  the  art,  I 
both  of  whom  excelled  the  ancient 
Romans  in  purity  of  design,  though 
the  first  could   not  give  up  the , 


EN 


ADDENDA  (RENAISSANCE). 


REN 


Gothic  window  tracery,  which  he 
suceessiyely  modified  to  his  round- 
arched    style  without  losing    its 
beauty.    They  were  succeeded  by 
Cronaca  and  Bramante,  the  latter 
of  whom  (bom  the  same  year  that 
Brunelleschi  died)  carried  the  re- 
-vival  of  classicism  to  its  perfection 
by  re-introducing  detached  colon- 
nades  and   hanging    architraves, 
never  attempted  since  the  fall  of 
ancient  art,  and  even  now  (by  Bra- 
mante) only  on  a  very  small  scale, 
in  the  round  chapel  in  the  cloister 
of  S.  Pietro  m  Monterio.     He  is 
considered  the  founder  of  the  Ro- 
man school,  as  Brunelleschi  was  of 
the  Florentine ;  and  his  design  for 
the  modem  St.  Peter's,  which  he 
commenced,  would  have  greatly 
excelled,  in  almost  every  kind  of 
merit,  the  present  jumble  of  twenty 
designs.  His  successor,  M.  Angelo, 
with    his    matchless    genius    for 
seizing  whatever  was  grand  rather 
than  beautiful,  returned   (in  the 
Capitoline  Museum)  to  the  classic 
simplicity  of  a  single  order,  and  an 
entablature  unbroken  from  comer 
to  comer:    the  renaissance  was 
complete,  and  the  modem  Roman 
architecture  having  (like  its  sister 
arts)  culminated  in  the  hands  of 
this  wonderful  man,  or  of  Vignola, 
forthwith  declined  rapidly.     San- 
micheli  of  Verona,  who  lived  from 
1484  to  1549,  (a  period  comprised 
wholly  in  the  life  of  M.  Angelo,) 
originated  that  more  fanciful  and 
luxurious  school  which  characte- 
rized the  renaissant  and  modem 
architecture    of  Venice    and   its 
territory,  and   (being  afterwards 
embellished  by  the  beautiful  pro- 
ductions  of  Sansovino,   Palladio, 
and  Scammozzi)  became  the  favo- 
rite model  for  the  schools  of  all 
transalpine    countries,    especially 
England. 

In  this  country,  a  way  was  pre- 
pared for  the  introduction  of  clas- 
sicism, by  certain  tendencies  of  our 
latest  After-Gothic,  the  florid  Per- 
pendicular, and  Tudor;  as  (I.)  the 


tendency  to  subordinate  the  arch 
and  archlet  to  the  frame-work  of 
vertical  and  horizontal  lines;  the 
vertical  constantly  increasing  in- 
deed in  numbeTt  but  the  horizontal 
in  strength  and  in^ortaneet  pro- 
bably from  a  feeling  that  the 
number  of  the  one  should  be  ba- 
lanced by  intensity  in  the  other. 
(II.)  By  these  horizontal  masses 
of  moulding  beginning  almost  to 
approximate  the  effect  of  classic 
entablatures,  in  their  division  into 
two  groups,  the  upper  and  greater 
answering  to  the  cornice,  the  lower 
and  smaller  to  the  architrave,  and 
the  intermediate  space  being,  like 
the  Aieze,  either  plain  or  sculp- 
tured, or  with  altemate  squares  of 
sculpture,  like  metopes,  but  never 
subdivided  horizontally.  (III.)  By 
the  roofs  being  reduced  in  pitch, 
(a  change  peculiar  to  the  Anglo- 
Gothic  decUne,)  and  by  towel's 
being,  on  the  same  principle, 
finished  without  spires.  (IV.)  By 
the  depression  of  the  arch,  the  as- 
similation thereof  to  a  semicircle 
or  semi-ellipse,  and  the  diminish- 
ing importance  attached  to  its 
pointf  though  that  was  never  en- 
tirely omitted  as  in  the  French 
After-Gothic,  called  Burgundian. 
(V.)  By  the  introduction  of  a 
large  and  bold  scale  of  carved 
ornament,  (as  in  King^s  College 
chapel,  where  the  architecture  and 
carving  are  out  of  all  proportion  to 
each  other,  a  leaf  being  often 
larger  than  an  arch  or  canopy,  and 
a  rose  larger  than  a  pedestal  and 
'statue  together,)  and  by  the  intro- 
duction, as  strikingly  seen  in  the 
same  building,  of  attached  orna- 
ment, quite  contrary  to  a  funda- 
mental Gothic  principle,  that  of 
decorating  by  the  removal  of  su- 
perfluous material,  and  not,  as  in 
classic  architecture,  by  the  addition 
of  omaments. 

These  several  predisposing  ten- 
dencies of  our  debased  After-Gothic 
rendered  it  easy  to  engraft  there- 
on those  Italian  details  which  dis- 


563 


REN 


ADDENDA  (RENAISSANCE). 


RE> 


tinguish  the  works  of  the  reign  of 
Henry  VIII.     The   chantries   of 
Bishops    Fox    and   Gardiner,   at 
Winchester,    are    instructive    ex- 
amples of  this  process ;  and  so  are 
the  tomh  of  Henry  VII.,  the  wood- 
work of  King's  College  chapel,  and 
much  of  the  ar.chitecture  of  Cam- 
bridge.   At  Ely  is  a  chantry  with 
purely-  Gothic  vaulting,  rather  re- 
sembling that  of  the  Mid-Gothic 
than  any  of  the  15th  century,  still 
less    of   the    16th,    but  without 
bosses ;  and  on  a  close  inspection, 
rendered   necessary  by  its   dark 
situation,  we  find  every  rib  com- 
posed of  Italian  cut  mouldings, 
while  the  intermediate  vault-sur- 
face,  of  plaster,  is  covered  with  the 
classic    foliage    commonly  called 
arabesque.     This  shows  capitally 
how  the  Gothic  (or  rather  After- 
Gothic)  principles  of  general  de- 
sign were  retained,  but  the  deiails 
rendered  more  and  more  pedantic, 
both  in  our  EUzabethan  fashion, 
and  in  the  corresponding  manners 
of  the  Continent ;  a  process  just 
the  reverse  of  every  true  advance 
that  has  taken  place  in  architec- 
ture ;  for  every  real  improvement 
(the   arch   for  instance,    or   the 
pointed  arch,  or  the  buttress)  has 
begun  in  main  structural  parts,  and 
descended  thence  into  details  and 
ornaments;  but  the  pedantry  of 
copying  classic  forms,  instead  of 
classic  principles,  begun,  except  in 
Italy,  in  the  smallest  and  least  es- 
sential details,  and  ascended  into 
larger  and  larger  features ;  the  con- 
stant aim  being  to  hide  a  smaller 
falsehood  by  a  greater,  and  thus  ge- 
nerally rendering  the  whole  system 

564 


of  building,  at  least  in  this  country, 
more  and  more  false,  till  at  length, 
in  the  Anglo-Greek  buildings  that 
followed  the  researches  of  Stuart 
and  Revett,  the  process  of  renau- 
sanee  carried  on  for  three  cen- 
turies became  complete,  t.  e.  a 
building — no  longer  a  collection 
of  many  little  or  a  few  great  dis- 
guises—  became  in  itself,  as  a 
whole,  one  immense  sham. 

Nor  does  the  popular  disrepute 
into  which  the  perfect  and  nnap- 
proachable  architecture  of  ancient 
Greece  has  now  been  brought  by 
these  attempts, — nor  yet  the  ro- 
mantic running  after  what  has  been 
(with  singular  ignorance)  mistaken 
first  for  a  '  national,'  and  then  for 
a  *  Christian'  style, — offer  any  pro- 
spect of  escape  from  the  effects  of 
this  *  renaissance,'  or  any  approach 
towards  a  true  renaissance  of  taste ; 
since  the  change  is  only  from  the 
mimicry  of  a  more  perfect  to 
that  of  a  less  perfect,  imd  (as  now 
practised  or  perhaps  practicable)  a 
more  limited  and  monotonous  sys- 
tem :  it  is  only  from  pseudo-Greek 
to  pseudo-Gothic, — from  a  sham 
temple  to  a  sham  church.  There 
is  no  hope  of  real  renaissance  till 
the  real  objects  of  the  art  be  agreed 
upon  and  attended  to, — till  it  be  ac- 
knowledged that  nothing  is  beau- 
tiful which  is  false,  and  till  im- 
provements are  introduced  from  , 
structural  parts  into  ornaments, —  , 
and  not,  as  they  have  been  in  all 
English  architecture  since  its  cul- 
mination in  the  time  of  the  first 
three  Edwards,  from  mere  oma- , 
ments  into  the  really  structural 
parts. 


THE  END. 


Hughes  &  Robiiwcc,  Printers,  King's  Head  Court,  Gough  Sc^uare. 


ELE 


ADDENDA  (ELECTRIC  TELEGRAPH). 


ELE 


ing  the  bell  and  needles  distinct 
from  each  other,  no  derangement 
of  the  one  is  to  be  feared  from 
injury  to  or  derangement  in  the 
other. 

Mr.  Cooke's  first  plan,  in  the 
extension  of  the  conducting  wires 
between  distant  points,  was,  as  has 
been  already  stated,  to  cover  each 
wire  with  cotton  or  silk,  and  then 
with  pitch,  caoutchouc,  resin,  or 
other  non-conducting  material,  and 
to  enclose  them,  thus  protected,  in 
tubes  or  pipes  of  wood,  iron,  or 
earthenware.  Excepting  in  those 
localities  where  the  suspension  of 
wires  is  impracticable,  as  in  streets, 
towns,  or  on  public  roads,  the  early 
plan  has  given  place  to  more  re- 
cent inventions.  In  1842,  a  patent 
was  obtained  by  Mr.  Cooke,  for  a 
means  of  suspending  and  insulating 
the  wires  in  the  air,  and  the  me- 
thod described  in  his  specification 
has  been  since  adhered  to,  with 
little  variation.  The  wires  are 
generally  of  iron,  which  is  galva- 
nized, to  protect  it  from  the  action 
of  the  atmosphere.  They  are  of 
about  one -sixth  of  an  inch  in  dia- 
meter, corresponding  to  No.  8  of 
the  wire-gauge.  Being  obtained 
in  as  great  lengths  as  possible,  in 
the  first  place,  successive  pieces 
are  welded  together,  until  a  coil  of 
about  440  yards  is  formed.  These 
rings  or  bundles  weigh  about  120 
pounds  each.  The  wires  are  sus- 
pended on  the  line,  from  stout 
squared  posts  or  standards,  of 
Dantzic  or  Memel  timber.  At 
each  quarter-mile,  a  stronger  post 
is  fixed,  from  which  the  succeeding 
lengths  of  wire  on  either  side  are 
strained  or  tightened  up.  Inter- 
mediate to  these  principal  posts, 
are  placed  smaller  standards  at 
from  45  to  55  yards  asunder,  for 
the  purpose  of  supporting  the  wires. 
The  straining  apparatus  is  very 
simple,,  consisting  merely  of  a  reel 
or  pulley,  turning  between  two 
cheeks  of  cast  iron,  and  carrying 
upon  its  axis  a  ratchet-wheel,  into 

560 


the  teeth  of  which  a  click  or  catct 
falls.  These  winding  heads,  showi 
vtrr,  figs.  7  and  9,  are  connected 
through  the  post  by  a    bolt  oi 
wrought  iron  b,  tapped  into  each 
head.     This  bolt  not  only  bean 
the  strain  of  the  wires,  but  also 
forms  the  metallic  communication 
between  their  ends  wound  on  the 
two*  reels.     In  order  to  insulate 
the  bolt  from  the  wood  of  the  post, 
the  hole  in  this  latter  is  bored  very 
large,  and  collars  of  eathenware, 
ttf  are  inserted  at  each  side,  in 
which  the  bolt  rests,  and  against 
their  outer  surfaces  th*e  winding 
heads  are  screwed  up  tight.  Fig.  9 
is  a  section  through  the  })08t  and 
collar,  showing  this  arrangement. 
Fig.  7  is  a  front,  and  8  a  side  view 
of  the  head  of  a  straining  or  quarter- 
post.       The    wires    are    usually 
arranged  in  two  vertical  planes,  at 
the  back  and  front  of  the  standards, 
or  intermediate  posts.    They  are 
not  strained  at  each  quarter-mile, 
but  at  intervals  of  half  a  mile  al- 
ternately ;  those  in  the  front  plane 
at  one  post,  and  those  in  the  back 
plane  at  the  next.    The  standards 
or  supporting  posts  have  merely  to 
sustain  the  weight  of  the  wires 
without  relation  to  their  tension. 
They  have  on  each  side  two  stout 
arms  of  oak  or  ash,  secured  bv 
bolts,    passing   from    one  to  the 
other,  and  resting  in  collars  of 
earthenware,  xxf  where  they  pass 
through  the  standard.     The  wires 
pass  through  pieces  of  earthen- 
ware, of  a  double  cone  shape,  e  «, 
fastened  to  the  outside  of  the  arms 
by  staples  or  clips,  having  a  nut 
and  screw  at  the  end.  These  staples 
embrace  the  cones  at  a  groove 
in  the  middle  of  their  length.    An 
arm  similar  to  .those  on  the  stand- 
ards is  fixed  to  the  back  and  front 
of  each  post  alternately,  to  support 
that  plane  of  wires  which  passes 
without  being  strained.    The  in- 
sulating earthenwares  between  the 
arm  and  post,  y  y,  are,  however, 
different  in  shape  from  those  used