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I 


{BY    AUTHOBITY.] 
O 

MANUAL 


OF 


HEAVY  ARTILLERY  SERVICE. 


PREPARED  FOR  THE  USE  OF   THE 


ARMY  AND  MILITIA  OF  THE  UNITED  STATES. 


r 


[  J.  C.  1IDBALL, 


MAJOR  SECOND  ARTILLERY,  BYT.   r.RIG.-GENX.,  F.  8.  A. 
COL.  A.  D.  C.  TO  THE  GEXERAL  OF  THE  ARMT. 


SECOND    EDITION. 


WASHINGTON',  D.  C.  : 

JAMES  J.  CHAPMAN". 

1881. 


Harvard    College    Library 
Mar.   13  r   1899 
From  tne  Library  of 
the  late  Col.  Henry  Lee, 


Entered  according  10  Act  of  Congress,  in  the  year  1880,  by 

James  J.  Chapman. 

In  the  Office  of  the  Librarian  of  Congress,  at  Washington,  I).  C. 


Pans  or  Tnoiua  McGai  k  Co., 

WABBDfOTOK,  D.  C. 


PREFACE. 


The  "basis  of  this  work,  so  far  as  the  Service  of  the  Piece 
and  the  Mechanical  Manoeuvres  are  concerned,  has  been  the 
"Circulars  of  the  U.  S.  Artillery  School,"  supplemented  by  the 
unwritten  customs  and  practices  of  that  institution. 

In  Field  Intrenchments,  "Mahan's  Field  Fortifications " 
was  used  as  a  reference,  supplemented  by  the  methods  intro- 
duced during  the  American  civil  war  of  1861-65,  and  adopted 
and  practiced  during  the  Franco -German  and  Russo- Turkish 
wars. 

In  Submarine  Mines,  the  works  of  Stotherd  and  of  Sleeman 
have  been  taken  as  authority. 

In  other  parts  of  the  work,  Benton's  "Ordnance  and  Gun- 
nery," Roberts'  "Hand -Book  of  Artillery,"  "Ordnance  Notes 
and  Memoranda,"  "Ordnance  Instruction  U.  S.  Navy,"  "Ord- 
nance Manual  XL  S.  Army,"  together  with  many  other  author- 
ities, have  been  consulted. 

In  the  labor  of  arranging  and  preparing  the  plates,  and  in 
various  other  matters,  I  am  indebted  to  Lieut.  C.  Chase,  3d  artil- 
lery; and  to  Lieut.  L.  V.  Caziarc,  2d  artillery,  for  the  admirably- 
arranged  Index. 

J.  C.  T. 

Fort  Monroe,  Va.,  June,  1880. 

(ill) 


IV  PREFACE. 


Report  of  the  Staff  of  the  U.  S.  Artillery  School  on  a  system  of 
instruction  for  heavy  -  artillery  troops,  submitted  by  Major 
J.  C.  Tidball,  2d  artillery,  Brevet  Brigadier- General,  U.  S.  A. 

Headquarters  U.  S.  Artillery  School, 

Fort  Monroe,  Ya.,  November  17,  1879. 

The  Adjutant-General  of  the  Army, 
Washington,  D.  O. 

Sir  :  The  MSS.  for  a  system  of  instruction  for  heavy-artillery  troops,  pre- 
pared by  Major  John  O.  Tidball,  2d  artillery,  Brevet  Brigadier-General, 
U.  S.  A.,  having,  in  accordance  with  the  instructions  of  the  General  of  the 
Army  contained  in  indorsement  dated  Headquarters  of  the  Army,  May  16, 
1879,  on  Major  TidbalTs  letter  of  March  29, 1879,  been  referred  to  the  Staff 
of  the  U.  S.  Artillery  School  for  examination,  the  Staff  respectfully  sub- 
mits the  following  as  its  report  thereon. 

The  work  has  evidently  been  designed  to  supply  a  want  long  felt  in  the 
artillery  service,  and  which  has  been  pointed  out  in  General  Orders  No.  3  of 
1876,  Headquarters  of  the  Army,  as  being  a  regular  and  more  comprehensive 
system  of  instruction  or  manual  for  heavy-artillery  troops. 

Its  general  divisions  are: 

1.  Preliminary  Instruction. 

2.  Service  of  the  Piece. 

3.  Mechanical  Manoeuvres. 

4.  Care  and  Preservation  of  Artillery  Material. 

5.  Transportation  of  Artillery. 

6.  Organization  and  Command  of  Artillery. 

7.  Employment  of  Artillery  in  Campaign. 

8.  Employment  of  Artillery  against  Armored  Vessels  and  in  Har- 

bor Defense. 

9.  Field  Intrenchments. 

10.  Attack  upon  Intrenchments. 

11.  Submarine  Mines. 

To  which  it  is  intended  to  add  a  short  chapter  on  Artillery  Salutes  and 
Ceremonies  and  Courtesies  between  land  and  naval  forces,  which  has  al- 
ready been  submitted  to  the  General,  of  date  October  18, 1879. 

The  Staff  has  the  honor  to  report  upon  the  various  divisions  of  the  work 
as  follows : 

1.  Preliminary  Instruction.  This  embraces:  1st.  Definitions  of  the 
various  kinds  of  artillery,  and  a  tabular  statement  of  the  U.  S.  system  foi 
land  service;  2d.  The  formation  and  marching  drill  of  heavy-artillery 
troops,— being  "battery,"  "platoon,"  and  "detachment  movements,"  and 
"  subdivision  movements,"  or  those  common  to  all  three  of  such  tactical 
sub-units. 

This  section  of  the  MSS.  has  met  with  critical  trial,  (with  troops  on  the 
drill-ground,)  close  scrutiny,  and  lengthy  discussion,  with  a  view  to  deter- 
mining what  may  be  best  calculated  to  insure  to  the  service  the  best  means 
for  the  performance  of  duty  devolving  upon  artillery  troops. 

It  is  found  that  the  proposed  marching  drill  is  based  upon  that  laid  down 
in  the  already-accepted  foot  drill  for  field  artillery,  and  that  the  latter  has 
been  modified  only  so  far  as  the  peculiarities  of  the  heavy-artillery  service 
render  necessary  or  desirable;  such,  for  example,  as  emancipation  from 
the  "  lock  step";  the  omission  of  "  section  "  movements  as  only  essential  for 
field  artillery;  the  assimilation  of  the  movements  of  the  guides  to  those  of 


PREFACE.  V 

the  infantry,  and  a  discontinuance  of  the  requirement  from  detachment 
chiefs  to  repeat  all  commands,  as  tending  toward  confusion  and  being 
entirely  unnecessary. 

The  few  additional  movements  are  essentially  adapted  from  the  infantry 
tactics,  and  render  the  proposed  marching:  drill  complete. 

It  is  the  judgment  of  the  Staff,  that  while  the  proposed  drill  is  essential 
for  the  service  of  heavy  artillery,  and  also  fully  suited  for  all  the  duties  of 
artillery  troops  in  garrison  or  elsewhere  in  the  presence  of  guns  it  is  at  the 
same  tune  so  closely  assimilated  to  the  tactics  of  infantry  in  its  principles 
as  to  render  the  transition  of  heavy-artillery  troops  into  infantry  formations 
a  thing  of  quick  and  easy  accomplishment.  The  same,  moreover,  may  be 
said  in  reference  to  its  adaptation  for  the  service  of  field  guns,  although  its 
departures  from  the  authorized  foot  drill  for  field  artillery  aro  but  slight, 
and  always  in  the  direction  of  assimilation  with  the  infantry  tactics,  which 
Is  understood  to  be  the  published  policy  of  the  General  of  the  Army  in  such 
questions. 

The  Staff  is  therefore  of  the  opinion  that  the  adoption  of  this  section  of 
the  MSS.  under  consideration  will  in  no  way  impair  the  efficiency  of  the 
artillery  regiments  in  the  infantry  duties  which  they  may  be  called  upon  to 
perform,  while  it  will,  on  the  other  hand,  facilitate  the  duties  pertaining  to 
their  special  arm,  because  its  tendency  as  a  means  of  discipline  and  esprit 
du  corps  is  to  strengthen  and  confirm  habits  of  thought  in  that  direction  by 
continually  reminding  the  men  of  their  weapon  as  artillerymen. 

2.  Service  of  the  Piece  ;  3.  Mechanical  Manoeuvres.  These  sections 
embrace  the  drill  for  all  classes  of  pieces  known  as  heavy  artillery,  and  the 
MSS.  are  the  result  of  several  years'  experience  at  the  Artillery  School,  of 
daily  study,  experiment,  and  observation. 

The  Staff  has  carefully  examined,  revised,  and  tested  this  section  at  the 
gnns,  and  is  of  the  opinion  that  it  meets  the  requirements  for  handling 
the  ordnance  now  in  use. 

4.  Care  and  Preservation  of  Artillery  Material  ;  5.  Transporta- 
tion of  Artillery.  These  sections  embrace  the  care  and  preservation  of 
all  classes  of  guns  and  their  belongings,  together  with  the  care  of  stores 
and  of  magazines ;  also  the  transportation  of  artillery  under  all  circum- 
stances of  service,  including  railroad  and  water  transportation  for  artillery 
material  and  animals.  The  MSS.  fere  the  result  of  a  life-time's  extended 
experience  in  the  U.  S.  artillery  service  in  peace  and  war.  Much  of  the 
matter  is  derived  from  actual  experience  in  the  war  of  1861-65,  and  has 
never  been  published  in  any  book  or  report.  The  Staff  is  confident  that  it 
supplies  a  vacancy  in  American  military  literature. 

6.  Organization  and  Command  of  Artillery;  7.  Employment  of 
Artillery  in  Campaign.  These  sections  embrace  all  of  a  subject  of  great 
magnitude,  which  is  indicated  by  their  titles,  that  there  seems  room  for  in 
a  book  of  the  kind  under  consideration.  It  cannot  be  doubted  that  there  is 
to  be  found  in  the  artillery  of  modern  war  the  points  of  support  with  which, 
to  counteract  the  effect  of  the  open  nature  of  infantry  fighting  consequent 
upon  the  breech-loader,  and  that  it  is  the  stable  element  of  battle  of  to-day 
in  the  hands  of  a  General,  because  the  dispersed  order  of  the  infantry  for 
action  renders  command  of  that  arm  at  all  times  difficult,  and  quite  im- 
possible as  the  fighting  progresses.  There  can  be  no  doubt,  furthermore, 
that  the  object  which  artillery  has  to  attain  must  be  comprehended  from 
the  beginning  of  its  action,  and  must  not  be  left  to  chance.  It  is  therefore 
advantageous,  to  say  the  least,  that  there  should  be  one  command ;  for  the- 
reason  that  everything  becomes  simpler  and  the  carrying  out  of  the  fight 
more  certain,  because  more  unity  of  will  pervades  it. 

To  support  this  view,  it  is  not  deemed  necessary  here  to  expatiate  upon* 
the  advantages  of  the  employment  of  artillery  in  large  masses,  because  the- 
object  is  self-evident  and  is  accepted  by  most  officers  of  experience  and  cul- 
ture as  an  established  fact.    These  sections  of  the  MSS.  are  the  result  of 


VI  PREFACE. 

•the  war  experiences  of  the  American  artillery,  and  hare  followed  closely 
-the  system  pursued  at  the  close  of  the  war  of  1861-65  in  points  of  organiza- 
tion and  command,  although  the  modified  conditions  of  the  battle  of  to-day 
"have  presented  a  few  corresponding  modifications  in  the  employment  of  artu- 
'lery  which  have  been  fully  treated  in  addition.  Although  we  have  passed 
through  one  of  the  most  sanguinary  conflicts  of  modern  times,  in  which  the 
.genius  of  the  American  soldier  was  severely  tested,  and  the  nature  of  the 
r*  terrain  "  entirely  different  from  any  which  is  treated  of  in  the  text-books 
heretofore  used  by  our  officers  in  study,  and  although  we  have  been  at  pro- 
found peace  with  the  world  for  fourteen  years,  with  ample  leisure  for  such 
undertakings,  it  is  a  singular  fact  that  no  American  work  is  extant  which  is 
based  upon  our  experiences,  giving  authoritative  instruction  in  the  applica- 
tion of  our  arms,  beyond  what  is  laid  down  in  the  drill-books. 

Now,  the  necessity  for  such  works  is  self-evident ;  for  although  we  are  not 
a  warlike  people,  we  possess  an  inherent  military  spirit  which  requires 
-direction  to  be  available  in  the  public  defense,  and  such  text-books  tend  to 
imbue  our  armies  with  character  and  military  intelligence  when  action  is 
required  of  them.  This  is  especially  so  in  the  case  of  auxiliary  troops,  such, 
as  volunteers  and  militia. 

The  Staff  is  of  opinion  that  these  sections  of  the  MSS.  constitute  a  step  in 
the  right  direction ;  and  while  the  subject-matter  pertains  largely  to  field 
■artillery,  it  is  not  considered  as  tenable  as  against  its  publication  in  this 
work,  because  it  is  germane  to  the  artillery  service  in  general  and  impor- 
tant to  be  preserved.  Moreover,  there  is  no  just  reason  in  favor  of  such  a 
divorce  between  the  light  and  heavy  artillery  service,  any  more  than  there 
has  been  found  one  in  favor  of  sucb  a  separation  of  the  light  and  heavy 
infantry  of  the  past. 

The  proposed  composition  of  an  artillery  force  in  regard  to  pieces  of  long; 
range,  or  for  the  development  of  curved  fire  in  the  field,  is  remembered  by 
the  Staff  as  identical  with  our  practice  in  the  war  of  1861-65,  and  the  princi- 
ple involved  is  confirmed  and  strengthened  by  the  more  recent  experiences 
-of  European  nations,  notably  in  the  Franco-German  and  Russo- Turkish 
wars. 

The  increased  zone  of  effective  infantry  fire  calls  imperatively  for  long- 
range  artillery  of  great  accuracy  and  quick  manipulation,  so  far  as  guns  are 
concerned ;  while  the  universal  use  of  field  intrenchments,  already  rendered 
necessary  by  a  murderous  infantry,  demands  with  equal  obstinacy  the  full 
use  and  development  of  curved  fire  from  mortars  on  the  part  of  artillery, 
both  in  the  attack  and  defense. 

The  provision  in  the  MSS.  for  the  use  of  such  pieces  as  we  now  have  in 
-service  is  therefore  regarded  by  the  Staff  as  an  advance  toward  meeting 
these  new  questions  as  far  as  possible  with  economy,  while  it  reserves  for 
future  settlement  the  question  of  improved  artillery  material  in  view  of 
these  demands.  "With  these  views,  the  Staff  cannot  too  strongly  recom- 
mend these  sections  of  the  MSS.  for  favorable  consideration  and  publica- 
tion. 

8.  Employment  of  Artillery  against  Armored  Vessels  and  in  Har- 
bor Defense.  This  section  embraces  as  much  of  this  important  subject  as 
will  admit  of  a  proper  limit  in  size  of  the  book  under  consideration.  It  is  a 
subject  upon  which  little  or  nothing  has  been  written,  and  the  expressed 
desire  of  the  General  of  the  Army  that  it  should  be  included,  is  regarded  as 
sufficient  reason  for  presenting  it. 

9.  Field  Intrenchments  ;  10.  Attack  on  Field  Intrenchments.  The 
MSS.  embrace  in  these  sections  as  much  of  the  subject-matter  indicated  by 
their  titles  as  is  deemed  essential. 

It  is  necessarily  a  compilation  upon  a  subject  which  is  older  than  the 
service  itself,  and  the  Staff  is  informed  that  it  is  inserted  upon  the  sugges- 
tion of  the  General  of  the  Army.  Further  comment,  therefore,  seems  un- 
>called  for. 


PREFACE. 


VII 


11.  Submarine  Mines.  This  subject  is  not  only  important,  bat  highly 
essential  to  be  understood  by  artillery  troops,  upon  whom  such  service  will 
most  likely  devolve  in  war ;  and  while  secrecy  in  the  matter  of  particular 
inventions  may  be  desirable,  such  secrecy  is  easily  within  the  control  of  the 
government. 

The  Staff  finds  no  reason  against  a  publication  of  so  much  of  the  subject 
of  submarine  mines  as  these  MSS.  embrace. 

In  conclusion,  the  Staff  is  of  the  opinion  that,  as  a  whole,  Major  TidbaH's 
work  is  full  and  complete  for  the  present  use  of  the  artillery  service ;  that  it 
is  in  harmony  with  the  experience  of  the  Army  in  war  as  well  as  with  the 
spirit  of-  its  organization  and  instruction  in  peace ;  and  that  it  is  calculated 
and  is  probably  invaluable  for  the  instruction  of  volunteer  and  militia,  artil- 
lery, upon  whom  much  of  the  service  of  heavy  artillery  will  devolve  in  any 
war,  and  whose  attention  should  undoubtedly  be  directed  to  such  Instruc- 
tion in  peace,  rather  than  toward  field-artillery  drill  merely,  as  is  now  the 
custom. 

In  this  latter  connection  the  Staff  respectfully  invites  attention  to  the  fact 
that  the  maintenance  of  militia  field  batteries  in  peace  is  expensive,  and 
never  attended  with  warrantable  success  from  the  very  nature  of  things, 
and  that  this  branch  of  artillery  can  only  be  kept  up  in  efficiency  by  the 
government. 

With  these  views,  the  Staff  of  the  U.  S.  Artillery  School  feels  warranted 
in  submitting  Major  Tidball's  work  for  the  favorable  consideration  of  proper 
authority,  recommending  its  immediate  publication. 

It  is  also  respectfully  recommended  that  the  work  be  adopted  for  the 
Army  and  for  the  Militia. 
We  have  the  honor  to  be,  very  respectfully,  your  obedient  servants. 


Headquarters  op  the  Army, 

Washington,  D.  C,  December  10, 1879. 
Hon.  Geo.  W.  McCraky, 

Secretary  of  War. 
Sir:   I  have  carefully  examined  the  manuscript  copy  of  the  proposed 
Heavy  Artillery  Tactics  prepared  by  General  Tidball,  and  the  reports  and 
papers  relating  thereto,  and  find — 

1st.  That  the  manuscript  of  the  Tactics  (a  better  designation  would  be- 
"Manual")  consists  of  twelve  parts. 

******** 

As  already  indicated,  it  would  seem  that  a  modification  of  the  title  of  the 
work  is  desirable,  and  I  would  suggest  the  following,  viz. : 

"A  Manual  for  the  Heavy  Artillery  Service,  prepared  for  the  use  of  the 
Army  and  Militia  of  the  United  States,  by  Major  J.  C.  Tidball,  2d  artillery, 
Brevet  Brigadier-General.  U.  S.  A.,  1879." 

With  the  title  thus  modified,  the  work  will  consist  of  parts  numbered  I, 
n,  III,  IV,  V,  VIII,  IX,  X,  XI,  XII,  or  ten  out  of  the  twelve  parts  prepared, 
and  I  therefore  recommend  that  it  be  published  accordingly,  as  modified. 

The  degree  of  authority  to  be  given  it  might  be  based  upon  that  givea 
January  24, 1876,  to  Roberts'  "Hand-Book,"  or  thus: 

"The  Manual  for  Heavy  Artillery  Service  prepared  by  Major  J.  O.  Tid- 
ball is  hereby  approved,  and  will  be  adopted  as  a  text-book  at  the  Artillery 
School  at  Fort  Monroe,  and  used  by  the  artillery  companies  (batteries> 
garrisoning  the  sea-coast  forts  of  the  United  States.  (Signed )  G.  W.  Mo 
Jrary,  Secretary  of  War." 

I  have  the  honor  to  be,  your  obedient  servant, 

(Signed)  W.  T.  SHERMAN,  General. 


Approved: 


(Signed) 


GEORGE  W.  McCRARY, 
Secretary  qf  War. 


HEAVY  ARTILLERY, 

U.  S.  Army,  1879. 


1.  By  the  term  Artillery,  is  understood  all  fire-arm*  discharged 
from  carriages,  in  contradistinction  to  small  arms,  which  arc  dis- 
charged from  the  hand.  It  also  denotes  the  particular  troops 
employed  in  the  service  of  such  fire-arms. 

2.  Artillery  is  known  as  Light  Artillery  and  Heavy  Artil- 
lery. Ligld  Artillery  is  formed  into  batteries  and  equipped  for 
field  evolutions;  Heavy  ArtiUei*y  embraces  all  artillery  not  so 
formed  and  equipped. 

3.  In  the  land  service  of  the  United  States  there  are  three 
kinds  of  pieces  of  Heavy  Artillery \  viz. :  the  GUN,  the  Howit- 
zer, and  the  Mortar. 

4.  They  are  distinguished,  according  to  their  principal  use, 
as  Siege  and  as  Sea-Coast  Artillery. 

5.  Siege  Artillery  is  used  in  the  attack  of  places,  and,  as  it 
accompanies  armies  in  their  field  operations,  is  mounted  upon 
carriages,  which  serve  for  its  transportation. 

It  is  also  employed  in  the  defense  of  field  works.  It  is  then 
sometimes  called  Garrison  Artillery. 

6.  Sea- Coast  Artillery  consists  of  the  heaviest  calibres,  and  is 
used  for  the  armament  of  permanent  works,  chiefly  on  the  sea- 
coast.  Their  carriages  do  not  subserve  the  purpose  of  transpor- 
tation. 

?.  For  the  sendee  of  Heavy  Artillery  there  are  four  distinct 
kinds  of  carriages  required,  viz. :  the  SlEGE,  the  CASEMATE, 
the  Barbette,  and  the  Mortar. 

8.  The  following  are  the  kinds  and  calibres  of  Heavy  Artillery 
belonging  to  the  present  system  of  artillery  for  the  land  service 
of  the  United  States. 

Note. — The  term  "system,"  as  here  used,  refers  to  the  char- 
acter and  arrangements  of  the  material  of  artillery,  as  adopted 
by  a  nation  at.  any  particular  epoch. 

(i) 


INTRODUCTION. 


PIECES. 


Kind. 


Calibre. 


Gun 


Bore. 


Smooth. 


20-in 

15-in 

"   13-in 

"   '  12-in 

44  10-in 

"  j    4.5-in.... 

Howitzer...     8-in |  Smooth 

"        ...I    5.8-in.— (flank 
1  casemate).... 

Mortar I  15-in 

44      1  13-in 

"      I  10-in 

"      t  10-in 

8-in 

5.8-in.  (Coehorn) 


Rifled.. 

tt 

.4 


It 
u 


it 
it 
(< 
tt 
(i 
it 
a 


Weight. 


116,000 
49,000 
37,000 
52,000 
40,681 
3,570 
2,600 

1,476 


17,120 

3,700 

1,900 

1,010 

164 


Designation. 


Sea-coast. 


(( 
«i 
tt 


tt 
it 


Siege. 


Sea-coast. 

«(       tt 


<t 


tt 
tt 


Siege. 


it 


In  service,  but  not  of  the  system. 


10-in 

8-in 

8-in.  (converted) 

10-in.    300-pdr  ^ 
8-in.    200-pdr 
6.4-in.  100-pdr 
4.2-in.    30-pdr.J 


Smooth. 

t< 


Pai-rott. 


Rifled. 


i  " 
I  « 
i        ti 


15,000 


16,160 

26,000 

16,300 

9,700 

4,200 


Sea-coast. 

tt       tt 


tt 
ii 
tt 


<t 
it 
tt 

tt 


Siege. 


Note. — The  20-inch  and  13-inch  smooth-bore,  and  the  10  and 
12  inch  rifle  gun?,  as  likewise  the  15-incli  mortar,  maybe  regard- 
ed as  experimental  pieces,  not  more  than  two  or  three  of  each 
kind  having  been  cast.  Carriages  for  tli<-iu  have  not  yet  been 
determined;  consequently  instructions  for  their  service  must 
be  omitted. 

The  4.5-inch  siege  gun,  8-inch  siege  howitzer,  5.8-inch  (flank- 
casemate)  howitzer,  the  5.8-ineh  (Coehorn)  mortar*  and  the  4.2- 
inch  (Par  rott)  siege  gun  are  mounted  on  wooden  carriages;  all 
other  pieces  on  iron  carriages. 

It  is  intended  that  the  15-inch  smooth-bore  and  12-inch  rifle 
guns  shall  have  the  same  carriage;  the  10-inch  smooth-bore  and 
8-inch  rifle  the  same  carriage. 

The  10-inch  smooth-bore  and  the  200-pounder  (Parrott)  have 
the  same  carriage,  and  the  8-inch  smooth-bore  and  100-pouuder 


INTRODUCTION.  8 

(Parrott)  have  the  same  carriage.    The  20-inch  smooth-bore  has 
a  separate  carriage. 

9.   Instruction  in  Heavy  Artillery  is  divided  into  ten  parts, 
viz. : 

I.    Preliminary  Instruction. 
II.    Service  of  tiie  Piece. 
HI.    Mechanical  Manoeuvres. 

IV.    Care  and  Preservation  op  Artillery  Mate- 
rial. 
V.    Transportation  op  Artillery. 
VI.    Employment  of  Artillery  aoainst  Armored 

Vessels  and  in  Harbor  Defenses. 
VII.    Field  Intrenchments. 

VIII.    Attack  and  Defense  of  Intrenched  Positions. 
IX.    Submarine  Mines. 

X.    Outlines  of  the  General  Properties  op  Per- 
manent Works. 
XI.    Salutes  and  Ceremonies. 


gart  Jfcwt. 


PRELIMINARY  INSTRUCTION. 

10.  The  officers  and  men  for  Heavy  Artillery  duties  should 
be  thoroughly  instructed  in  the  4*  School  of  the  Soldier,"  Light 
Artillery  and  Infantry  Tactics.  The  preliminary  instructions 
herein  given  are  only  such  as  are,  in  addition,  necessary  for  the 
more  general  duties  of  artillerymen. 

11.  The  term  piece,  as  herein  used,  applies  to  cannon,  wheth- 
er gun,  howitzer,  or  mortar.  As  a  matter  of  convenience,  it  is 
also  used  to  designate  both  cannon  and  carriage  when  the  can- 
non is  mounted. 

Detachment. 

1  a.  The  men  employed  in  the  service  of  artillery  are  called 
artillerymen. 

The  artillerymen  for  a  single  piece  constitute  a  gun  detach- 
ment, and  vary  in  number  witti  the  size  and  kind  of  piece. 

13.  The  detachment  (Fig.  1,  Plate  I)  is  composed  of  two 
non-commissioned  officers,  and  from  two  to  ten  privates.  The 
senior  non-commissioned  officer  is  called  chief -of '-detachment ; 
the  other,  gunner.    The  privates  are  called  cannoneers. 

14.  The  detachment  is  formed  in  double  rank,  and  told  off 
from  the  right  as  follows :  No.  1  is  on  the  right,  of  the  rear  rank; 
No.  2  in  front  of  No.  1 ;  No.  3  on  the  left  of  No.  1 ;  No.  4  on 
the  left  of  No.  2;  the  other  numbers  follow  in  the  same  order, 
even  numbers  in  the  front,  odd  in  the  rear  rank.  When,  by 
facing  about,  the  front  becomes  the  rear  rank,  the  numbers  of 
the  cannoneers  do  not  change. 

15.  The  chief -of -detachment^  when  in  line,  is  on  the  right  of 
the  front  rank  of  his  detachment.  When,  by  facing  about,  the 
front  becomes  the  rear  rank,  he  does  not  change  to  the  other 
flank,  but  steps  forward  into  the  rear  (now  become  the  front) 
rank.    When  in  column  of  files,  he  is  as  if  he  had  faced  with  his 

Jetachment  from  line. 

16*   The  gunner,  in  line,  and  in  column  of  platoons,  is  two 

?ards  in  rear  of  the  centre  of  his  detachment,  except  when  be- 

onging  to  the  left  detachment  of  the  battery  in  line,  or  of  platoon 

lien  in  column  of  platoons* — in  either  of  which  cases  he  places 

imself  on  the  left  of  the  front  rank  of  his  detachment,  and  is 

(5) 


6  PRELIMINARY  INSTRUCTION. 

the  guide  of  that  flank  of  the  battery  or  platoon ;  in  column  of 
detachments,  he  is  on  a  line  with  the  front  rank  of  his  detach- 
ment, on  the  flank  towards  which  the  wheel  was  made,  and  one 
yard  from  it;  in  column  of  flies,  he  is  as  if  he  had  faced  with  his 
detachment  from  line.  When  he  is  the  left  guide  of  the  battery 
or  platoon,  and  by  facing  about  the  front  becomes  the  rear  rank, 
he  does  not  quit  his  position  on  the  flank  of  his  detachment,  but 
steps  forward  into  the  rear  (now  become  the  front)  rank. 

17.  When,  by  wheeling  about,  the  right  subdivision  becomes 
the  left,  the  gunner  who  was  the  left  guide  resumes  his  place  in 
rear  of  his  detachment,  and  the  gunner  of  the  detachment  which 
has  now  become  the  left  places  himself  on  its  left  flank  as  guide 
of  the  battery  or  platoon. 

Platoon, 

18.  Two  or  more  detachments  form  a  platoon,  commanded 
by  a  lieutenant ;  and,  if  circumstances  will  permit,  the  battery 
will  be  divided  into  as  many  platopns  as  there  are  lieutenants 
to  command  them. 

Battery. 

19.  The  term  battery  is  now  applied  to  what  was  formerly- 
called  a  company.  It  is  also  used  to  designate  a  number  of 
pieces  of  artillery  in  position  for  service;  likewise  the  place  in 
a  work  where  they  may  be  located  ;  and  it  further  denotes  cer- 
tain positions  in  the  manoeuvres  with  individual  pieces.  When- 
ever this  term  is  used,  its  meaning  must  be  determined  from  the 
context. 

20.  The  battery  is  assigned  to  specified  pieces  in  the  work, 
the  number  depending  on  the  strength  of  the  battery;  the  lat- 
ter is  divided  into  a  like  number  of  detachments,  and  these  are 
assigned  to  the  individual  pieces.  Although  thus  assigned  to  the 
service  of  specified  pieces,  the  several  detachments  should  be 
instructed  for  the  service  of  any  piece  in  the  command.  The 
men  of  each  detachment  should  be  selected  for  their  individual 
fitness  for  the  particular  piece. 

ft\.  The  detachments  receive  permanent  n umbers,  from  right 
to  left,  the  first  detachment  being  on  the  right. 

Platoons  are  in  like  manner  permanently  designated. 

$2.  During  the  manoeuvres,  platoons  temporarily  change 
their  numbers,  when,  by  wheeling,  or  by  facing,  the  original 
right  becomes  the  left.  In  column,  they  are  numbered  from 
the  head,  the  leading  one  being  always  the  first, 

23.  The  men  of  each  detachment  full  in  according  to  height, 
the  tallest  men  on  the  right;  thus  bringing,  as  a  general  rule, 
the  strongest  men  to  the  duties  requiring  greatest  strength. 


PRELIMINARY   INSTRUCTION.  7 

Posts  of  officers,  non-commissioned  officers,  fyc. 

f&4L.  (Figs*  2  and  3,  Plate  L)  The  captain,  in  lino,  is  four  yard* 
in  front  of  the  centre  of  the  battery;  in  column,  on  the  side  of 
the  guide,  or  on  the  side  towards  which  the  subdivisions  are 
dressed,  four  yards  from  the  flank  and  opposite  the  centre  of  (lie 
column ;  as  instructor,  lie  goes  wherever  his  presence  is  neces- 
sary. 

25.  The  senior  lieutenant  takes  post  with  the  right  platoon ; 
the  next  in  rank  with  the  left  platoon ;  the  third  witli  the  sec- 
ond from  the  right,  and  the  fourth  with  the  second  from  tin* 
left. 

Each  lieutenant  is  chief  of  the  platoon  with  which  he  is  posted  ; 
and  in  line,  and  in  column  of  platoons,  is  two  yards  in  front  of 
the  centre  of  his  platoon  ;  in  column  of  detachments,  each  is  on 
the  side  of  the  guide,  or  on  the  side  towards  which  the  subdivis- 
ions are  dressed,  two  yards  from  the  flank  of  the  column,  and 
opposite  the  centre  of  the  platoon ;  (they  are  always  on  the  side 
opposite  that  of  the  gunners:  par.  23;)  in  column  of  flies,  each 
as  if  he  had  faced  with  the  battery  from  line,  except  the  chief  of 
the  leading  platoon,  who  takes  post  by  the  side  of  the  leading 
guide. 

26.  The  first-sergeant,  in  line,  is  on  the  right  of  the  battery, 
aligned  on  the  front  rank  and  one  yard  from  it;  in  column  of 
platoons  and  of  detachments,  he  is  on  the  same  side  as  the  chief- 
of-platoon,  aligned  on  the  front  rank  of  the  nearest  subdivision 
atid  one  yard  from  it;  in  column  of  files,  he  is  as  if  he  had 
faced  with  the  battery  from  line.  When  two  or  more  batteries 
are  united  in  line,  he  is  as  explained  in  (see  Battalion). 

ftHm  Each  chief  -  of  -  detachment  is  on  the  right  of  the  front 
rank  of  his  detachment,  as  in  par.  L~>. 

28.  Each  gunner  is  two  .yards  in  rear  of  the  centre  of  his  de- 
tachment, except  as  provided  in  par.  16. 

29.  The  trumpeters,  in  line,  are  in  one  rank  on  the  right  of 
the  first-sergeant,  and  two  yards  from  him;  in  column  of  pla- 
toons and  of  detachments,  they  wheel  to  the  side  indicated,  and 
are  either  four  yards  in  front,  of  the  centre  of  the  leading  subdi- 
vision, or  four  yards  in  rear  of  the  last  subdivision,  according  as 
^ie  column  has  been  formed  towards  their  flank  of  the  battery, 

r  the  opposite;  in  column  of  files,  they  are  as  if  they  had  faced 
nth  the  battery  from  line,  and  the  one  in  rear  stepped  to  the 
ight,  or  left,  of  the  other,  according  as  they  faced  to  the  right 
>r  left. 

30.  The  guides  of  a  battery  or  platoon  are  the  non-com  mis- 
oned  officers  posted  on  its  right  and  left ;  the  guides  of  a  de- 


8  PRELIMINARY   INSTRUCTION. 

tachment  are  the  chief-6f-detachmeut  and  the  front-rank  man 
on  the  opposite  flank. 

31*  The  chief  s-of-detachments  and  platoons  give  or  repeat 
commands  only  when  it  is  prescribed.     This  rule  is  general. 

32.  For  the  purpose  of  instruction  in  marching  drill,  the  de- 
tachments are  equalized,  and  should  not  consist  of  more  than 
eight  cannoneers. 

33.  When  the  battery  faces  about  in  line,  the  first-sergeant 
and  the  trumpeters  face  about,  but  do  not  change  to  the  other 
flank. 

34L  When  the  number  of  platoons  and  detachments  are  so 
reduced  as  to  make  surplus  officers  or  non-commisdoned  officers, 
tiiese  take  their  places  two  yards  behind  the  rear  rank,  and,  with 
the  gunners,  act  as  file-elosers;  the  officers,  and  likewise  the 
non-commissioned  officers,  distribute  themselves  at  equal  dis- 
tances from  right  to  left,  according  to  rank. 

35.  It  is  the  duty  of  file -closers  to  rectify  mistakes,  and  in- 
sure steadiness  and  promptness  in  the  ranks. 

36.  In  all  changes  of  formation,  as  soon  as  the  movement 
permits,  the  officers  and  non-commissioned  officers,  whose  posts 
are  changed,  hasten  by  the  shortest  routes  to  their  posts  in  the 
new  formation;  except,  when  in  column  of  detachments,  the 
detachments  are  wheeled  about,  they  do  not  change,  unless 
directed  to  do  so  by  the  instructor. 

To  form  the  battery. 

31.  At  the  sounding  of  the  assembly,  the  first-sergeant,  facing 
the  battery  and  six  yards  in  front  of  its  centre,  commands  : 

1.  Fall  in,  2.  Left,  3.  Face,  4.  Call  rolls,  5.  Report. 

The  battery  being  divided  into  permanent  detachments,  as 
prescribed  iu  par.  28,  at  the  command  fall  in  the  chiefs-of- 
detachmeut  place  themselves  on  tiie  line  facing  to  the  right, 
and  at  sufficient  distance  from  each  other  for  the  formation  of 
tiie  detachments;  the  men  of  each  detachment  fall  in,  facing 
to  the  right,  the  front-rank  men  covering  their  chief;  the  sig- 
nal having  ceased,  the  first-sergeant  causes.  If  necessary,  the 
detachment  to  close  up. 

At  the  command  face,  all  face  to  the  left. 

At  the  command  call  rolls,  the  chief s-of-detach men t  step  out 
two  yards  in  front  of  the  centres  of  their  detachments,  face 
towards  them,  call  their  rolls,  and  resume  their  places  in  the 
ranks. 

At  the  command  report,  the  chie  f  s-of-detach  men  t,  standing 
fast,  report  to  the  first-sergeant,  in  succession  from  right  to  left, 


PRELIMINARY   INSTRUCTION.  9 

the  results  of  their  roll-calls;  the  first-sergeant  then  commands : 
Call  off.  when  each  chief-of-detachment  steps  promptly  in 
front  of  his  detachment  ami  faces  toward  it  to  see  that  the  men 
call  off  properly;  each  man  in  turn  calls  out  distinctly  his  num- 
ber— one*  two,  three,  and  so  on  ;  the  gunner  calls  last — gunner. 

38.  If  the  front  and  rear  rank  contain  an  unequal  number 
of  cannoneers,  tin;  odd  file  is  the  left  front-rank  man,  and  the 
vacant  space  is  in  rear  of  him  until  after  calling  oft';  the  left 
man  of  the  rear  rank  then  steps  to  his  left  and  covers  the  left 
front-rank  man  ;  he,  however,  retains  his  number,  and  at  the 
piece  takes  the  position  belonging  to  it. 

The  first-sergeant  then  faces  about,  salutes  the  captain,  or 
other  officer  acting  in  his  place,  reports  the  result  of  the  roll- 
calls,  and  takes  his  position  in  line. 

39.  If,  for  marching  drill*  or  any  other  special  purpose,  the 
detachments  are  required  of  equal  size,  this  is  effected  by  trans- 
ferring men  from  the  stronger  to  the  weaker  detachments;  but 
for  ordinary  service,  such  as  marching  to  and  from  the  place  of  ex- 
ercise with  the  pieces,  the  detachments  need  not  be  of  equal  size. 

40.  When  a  battery  is  to  form  for  ordinary  garrison  pur- 
poses, such  as  fatigue  duties,  or  for  roll-calls  when  the  battery 
is  small  in  numbers,  the  first-sergeant  places  himself  six  yards 
in  front  of  the  centre,  facing  towards  the  battery,  and  com- 
mands :  Faxl  in. 

At  the  command  fall  in*  the  senior  duty-sergeant  places  him- 
self, facing  towards  the  right,  at  the  point  where  the  right  of  the 
battery  is  to  rest ;  the  privates  fall  in,  in  two  ranks,  facing  to 
the  right,  the  front-rank  men  covering  the  senior  duty-sergeant. 

The  second  duty-sergeant  takes  his  place  in  rear  of  the  last 
front-rank  man,  and  the  other  non-commissioned  officers  place 
themselves,  facing  in  the  same  direction  as  the  rest,  in  such 
positions  as,  when  they  face  to  the  left,  will  bring  them  equally 
distributed  along  the  line ;  the  first-sergeant  commands  :  1. 
Left,  2.  Face,  when  the  men  face  to  the  left;  he  then  calls 
tlie  roll,  reports,  as  in  par.  38,  and  takes  his  post  in  line ;  at 
the  same  time  the  officers  take  posts. 

41*  If  the  battery  is  to  exercise  at  marching  drill,  after  being 
thus  formed,  the  first-sergeant,  before  reporting,  divides  it  into 
the  desired  number  of  detachments  of  equal  size,  and  assigns 
the  chiefs-of-detachment  and  gunners  to  their  respective  detach- 
ments, who  take  their  posts  accordingly.  The  detachments  call 
off  as  before. 

If  the  exercise  is  to  be  at  the  pieces,  the  detachments  are  told 
off  in  sizes  to  suit  the  particular  pieces,  and  the  chiefs  and  gun- 
nel's are  assigned  as  before. 


10  MARCHING  MANOEUVRES. 

42.  The  manoeuvres  of  a  separate  platoon  are  identical  with 
those  of  a  battery,  the  command  platoon  being  substituted  for 
battery. 

43.  The  manoeuvres  of  a  separate  detachment  are  analogous 
to  those  of  a  battery,  the  commaud  detachment  replacing  that 
of  battery.  The  chief-of-detachment  acts  as  instructor,  and  is 
replaced  on  the  right  flank  of  the  detachment  by  the  gunner. 

44*  The  captain,  or  in  his  absence  the  next  oflieer  in  rankt 
acts  as  instructor. 

45.  All  movements  not  specially  excepted  may  be  executed 
in  double  time.  If  the  movement  be  from  a  halt,  or  when  march- 
ing in  quick  time,  the  command  double  time  precedes  the  com- 
mand march  ;  if  marching,  this  command  is  omitted. 

46*  Officers,  when  on  duty  with  men,  will  habitually  wear 
their  swords;  when  in  ranks,  or  when  giving  commands,  the 
sword  must  be  drawn.  Instruction  in  the  use  of  the  sword  is 
given  in  Light  Artillery  Tactics. 

4T.  The  trumpet  signals  and  inles  for  using  them  are  those 
prescribed  in  Light  Artillery  Tactics. 

48*  When  artillery  is  armed,  equipped,  and  serving  as  either 
cavalry  or  infantry,  and  organized  into  commands  of  these 
arms,  it  will  conform  to  the  formation  and  tactics  prescribed* 
respectively,  for  these  branches  of  service. 

Marching  Manoeuvres. 

The  following  manoeuvres  are  those  most  essential,  and  gen- 
erally used  by  Heavy  Artillery  troops.  The  principles  embraced 
in  them  will  serve  for  more  extended  exercises. 

To  open  ranks. 

49.  Being  in  line,  at  a  halt,  the  instructor  commands  : 

1.  Rear  open  order ;  2.  March,  3.  Front. 

At  the  first  command,  the  chiefs-of-detachment,  and  gunner 
acting  as  left  guide,  step  briskly  three  yards  to  the  rear  to  mark 
the  new  alignment  of  the  rear  rank;  the  instructor  goes  to  the 
right  flank  and  sees  that  these  non-commissioned  officers  are  on 
a  line  parallel  to  the  front  rank. 

50.  When  the  battery  is  not  divided  into  detachments,  the 
non-commissioned  officer  on  the  right  and  left  flanks,  respect- 
ively, steps  back  to  mark  the  line. 

At  the  command  march^  the  chief s-of-platoon  step  forward 
one  yard,  thus  bringing  themselves  three  yards  in  front  of  the 
battery.     Should  there  be  officers  in  the  line  of  tile-closers,  they 


MARCHING   MANCBUVRKS.  11 

pass  around  the  nearest  flank  and  place  themselves  in  the  line* 
of  officers  opposite  their  former  positions.  The  front-rank  m<m 
dress  to  the  right;  the  rear-rank  men  cast  their  eyes  to  the  right* 
step  backwards,  halt  a  little  in  rear  of  alignment,  and  then  dress* 
to  the  line  established  by  the  non-commissioned  officers  who 
have  stepped  back;  the  file-closers  step  back  at  the  same  time* 
taking  a  distance  of  three  yards  from  the  rear  rank. 

The  instructor  superintends  the  alignment  of  the  chief  s-of- 
platoon  and  of  the  front  rank,  and  the  first-sergeant,  or  in  his 
absence  the  chief  of  the  right  detachment,  that  of  the  rear  rank; 
the  instructor  verifies  the  alignment  of  the  rear  rank  and  of  tint 
file-closers  ;  the  chief s-of -platoon  and  file-closers  cast  their  eye* 
to  the  front  as  soon  as  their  alignment  is  verified. 

At  the  command  fronts  the  non-com  missioned  officers  who 
have  stepped  back  to  mark  the  line  for  the  rear  rank  resume- 
their  places  in  the  front  rank,  and  the  men  cast  their  eyes  to  the* 
front;  the  first-sergeant  returns  to  his  post,  and  the  instructor 
places  himself  six  yards  in  front  of  the  centre  of  the  battery, 
facing  to  the  front. 

To  close  ranks. 

52*  Being  at  a  halt,  the  instructor  commands : 

1.  Close  order,  2.  March. 

At  the  command  inarch,  the  chiefs-of-platoon  face  about  and 
resume  their  posts  in  line;  the  rear  rank  closes  to  facing  dis- 
tance, each  man  covering  his  front-rank  man;  the  file-closers- 
move  forward  with  the  rear  rank  and  take  their  posts  in  line  ;: 
the  instructor  resumes  his  post  in  line. 

Alignments. 

53.  Being  in  line,  at  a  halt,  with  the  ranks  open,  the  in- 
structor establishes  two  or  four  men  as  a  basis  for  each  rank,  at 
first  in  parallel  and  afterward  in  oblique  directions  to  the  front 
of  the  battery.     He  then  commands  : 

1.  Byfile,'2.  Right  (or  left),  3.  Dress,  4.  Front;  or,  1.  Ry 
file,  2.  Right  (or  left)  backward,  3.  Dress,  4.  Front;  ort 
1.  Right  (or  left),  2.   Dress,  3.   Front;  or,  1.  Right  (or 
left)  backward,  2.  Dress,  3.  Front. 

Each  rank  is  aligned  as  explained  in  the  School  of  the  Soldier,, 
the  rear  rank  remaining  parallel  to  the  front,  rank.  The  ranks 
being  closed,  the  alignments  are  repeated  in  the  same  manner. 

In  all  alignments,  the  file-closers  preserve  their  distances  from* 
the  rear  rank. 


12  MARCHING   MANOEUVRES. 

To  rest. 

54.  Being  at  a  halt,  the  instructor  commands  : 

1.  Battery,  2.  Rest;  or,  1.  In  place,  2.  Best. 
To  resume  attention,  the  instructor  commands : 

1.  Battery,  2.  Attention. 

To  dismiss  the  battery. 

55.  Being  in  line,  at  a  halt,  the  instructor  commands  :  Dis- 
miss THE  BATTERY. 

The  officers  return  their  swords  and  fall  out ;  the  first-sergeant 
then  commands : 

1.  Break  ranks,  2.  March. 

To  march  in  line. 

56.  The  battery  being  at  a  halt,  and  correctly  aligned,  the 
Instructor  commands : 

1.  Forward,  2.   Guide  {right  or  left),  3.  MARCH. 

At  the  command  forward,  the  guide  selects  two  points  on  a 
line  passing  through  him  and  perpendicular  to  the  front  of  the 
battery ;  at  the  command  march,  the  men  step  off  with  life ;  the 
guide  observes  with  the  greatest  care  the  length  and  cadence  of 
the  step,  marches  on  the  two  points  he  has  chosen,  and  selects 
others  in  advance  on  the  same  line  before  reaching  the  first ;  the 
iilo-closers  keep  at  their  proper  distances  from  the  rear  rank. 

To  halt  the  battery  and  to  align  it. 

57.  The  instructor  commands  : 

1.  Battery,  2.  Halt,  3.  Right  (or  left),  4.  Dress,  5.  Front. 

To  march  in  the  slioH  step  ;  to  mark  time  ;  to  change  step  ;  to 
side  step ;   to  march  backward ;   to  oblique  in  line  ;   to  pass 
from  quick  time  to  double  time,  and  the  reverse. 

Executed  as  explained  in  the  School  of  the  Soldier,  substi- 
tuting, in  the  commands,  battery  for  squad,  wherever  the  latter 
occurs. 

58.  In  the  oblique  march,  the  ranks  remain  parallel  to  their 
former  position. 

59.  In  marching  in  double  time  the  left  hand,  instead  of  be- 
ing raised,  steadies  the  scabbard ;  the  sword,  if  drawn,  is  held 
in  a  vertical  position  in  the  right  hand. 


MARCHING   MANOEUVRES.  IS 

To  wheel  the  battery. 

60.  Being  in  line,  at  a  halt,  the  instructor  commands: 

1.  Right  (or  left)  wheel*  2.  March,  3.  Battery,  4.  Halt,  5.  Left 

(or  right),  6.  Dress,  7.  Front. 

At  the  command  march,  the  battery  wheels  to  the  right  on  a 
fixed  pivot;  the  left  guide  conducts  the  marching  flank;  the 
right  guide  stands  fast,  so  that  the  breast  of  the  pivot-man  may 
rest  against  his  left  arm  at  the  completion  of  the  wheel ;  the 
chiefs -of -platoon  face  about  at  the  first  command,  step  back- 
ward at  the  second,  and  superintend  the  movements  of  their 
platoons,  resuming  their  positions  at  the  command  front;  the 
instructor  hastens  by  the  shortest  line  to  place  himself  directly 
in  front  of  the  pivot-guide,  and  at  a  distance  from  him  equal  to 
the  length  of  the  battery  front,  and  faces  to  the  late  rear. 

At  the  command  halt,  given  when  the  left  guide  is  three  yards 
from  the  perpendicular,  the  battery  halts ;  the  left  guide  of  the 
battery  advances  quickly,  places  his  left  elbow  lightly  against  the 
breast  of  the  instructor,  who  establishes  him  on  the  line. 

At  the  command  dress*  the  men  dress  up  to  the  line  of  the 
guides;  at  the  command  front,  the  right  guide  places  himself  on 
the  right  of  the  pivot-man. 

Bl.  To  continue  the  march  upon  the  completion  of  the  wheel, 
the  instructor,  without  placing  himself  in  front  of  the  pivot- 
guide,  commands:  3.  Forward,  4.  March,  5.  Guide  right  (or 
left).  The  third  com  maud  is  given  when  the  guide  on  the  march- 
ing flank  is  three  yards  from  the  perpendicular  to  the  original 
front;  the  fourth,  the  instant  the  wheel  is  completed  ;  and  the 
fifth  immediately  after.  The  guide  on  the  pivot  places  himself 
by  the  side  of  the  pivot-man  at  the  command  forward. 

62.  Marching  in  line,  the  instructor  commands  : 

1.  Right  (or  left)  wheel,  2.  March,   3.  Forward,  4.  March. 

At  the  second  command,  the  battery  wheels  to  the  right  on  a 
movable  pivot ;  the  command  forward  is  given  when  the  guide 
is  three  yards  from  the  perpendicular,  and  the  fourth  command 
at  the  instant  the  change  of  direction  is  completed. 

In  wheeling  on  a  movable  pivot,  the  command  forward  is  given 
in  sufficient  time  to  add  march  the  instant  the  wheel  is  comple- 
ted.    This  rule  is  general. 

63*  Marching  in  line,  to  effect  a  slight  change  of  direction, 
the  instructor  commands : 

Incline  to  the  right  (or  left). 

Ike  guide  advances  gradually  the  left  shoulder,  and  marches 


14  MARCHING   MANOEUVRES. 

in  the  new  direction  ;  all  the  files  advance  the  left  shoulder  and 
•conform  to  the  movements  of  the  guide,  lengthening  or  shorten- 
ing the  step  according  as  the  change  is  towards  the  side  of  the 
iguide,  or  the  opposite. 

To  march  by  the  flank, 

64.  Being  in  line,  at  a  halt,  the  instructor  commands : 
1.  Bight  (or  left),  2.  Face,  3.  Forward,  4.  March. 

If  marching,  the  instructor  commands : 

1.  By  the  right  (or  left)  flank*  2.  March. 

The  march  in  column  of  files  is  usually  in  quick  time;  if  nec- 
essary to  march  in  double-time,  the  distance  between  files  is 
increased  to  thirty-two  inches,  and,  upon  halting,  the  files  close 
to  facing  distance. 

65.  To  halt  the  battery,  and  form  it  in  line,  the  instructor 
commands:  1.  Battery,  2.  Halt,  3.  Laft  (or  right),  4.  Face; 
or,  to  form  line  and  continue  the  march  :  1.  By  the  left  (or  right) 

Jlank,  2.  March,  3.  Guide  {right  or  left). 

To  oblique  and  to  change  direction  in  column  of  files.  Exe- 
cuted by  the  commands  and  means  prescribed  in  the  School  of 
4;he  Soldier. 

To  form  column  of  platoons  to  the  right,  or  left, 

66.  Being  in  line,  at  a  halt,  the  instructor  commands: 

Platoons  right  (or  left)  wheel,  2.  March. 

At  the  first  command,  each  chief-of-platoon,  facing  it,  cautions 
it :  Right  wheel. 

At  the  command  march,  each  platoon  wheels  to  the  right  on  a 
fixed  pivot,  as  explained  for  the  wheel  of  a  buttery.  Each  chief, 
•superintending  the  wheel  of  his  platoon,  hastens  to  the  point 
where  the  left  of  his  platoon  is  to  rest  on  the  completion  of  the 
wheel;  faces  to  the  late  rear,  and  when  the  marching  Hank 
approaches  him,  commands:  1.  Platoon,  2.  Halt,  3.  Left,  4. 
Dress,  5.  Front. 

At  the  command  halt,  the  guide  on  the  marching  flank  places 
his  left  arm  against  the  breast  of  his  chief,  wiio  then  aligns  the 
platoon  and  takes  his  post  in  front  of  its  centre,  after  command- 
ing/ro?^.  If  marching,  the  movement  is  executed  as  just  ex- 
plained, the  pivot-guides  halting  at  the  command  march,  mark 
time  in  their  places,  and  conform  to  the  movements  of  the  front 
of  the  platoon. 

67.  In  every  case  where  a  line  is  broken  in  platoons?  the 


MARCHING   MANOEUVRES.  15 

gunner  of  the  left  detachment  of  each  platoon,  if  not  already 
there,  hastens  to  place  himself  on  the  left  flank  of  his  detach- 
ment a*  soon  as  the  movement  will  permit;  lie  then  becomes 
the  left  guide  of  his  platoon.  When  the  line  is  reformed,  he 
hastens  to  resume  his  former  position. 

68*  To  form  column  of  platoons  to  the  right  or  left  and  con- 
tinue the  march  instead  of  halting,  the  instructor  commands: 

1.   Continue  the  march,  2.  Platoons  right  (or  left)  wheel,   3. 
March,  1.  Forward,  5.  March,  6.  Guide  (right  or  left). 

The  movement  is  executed  as  before,  except  that  each  chief 
remains  in  front  of  the  centre  of  his  platoon,  and  the  platoons 
move  straight,  forward  at  the  fifth  command.  The  leading  guide 
prolongs  aecurately  his  line  of  march  by  choosing  successively 
points  in  advance  ;  the  other  guides  preserve  with  care  the  trace, 
the  step,  and  wheeling  distance. 

To  put  the  column  of  platoons  in  march,  and  to  halt  the  column. 

69.  The  instructor  commands  : 

1.  Forward,  2.   Guide  (right  or  left).  3.  MARCH,  and  1.  Bat- 
tery, 2.  Halt. 

To  form  line  to  the  right  or  left  from  column  of  platoons. 

TO.   Being  at  a  halt,  the  instructor  commands  : 

1.  Right  (or  left)  into  line  wheel,  2.  March,  3.  Battery,  4. 
Halt,  5.  Left  (or  right).  G.  Dress,  7.  Front,  8.  Guides, 
9.  Posts. 

At  the  first,  command,  each  chief-of-platoon,  facing  it,  cautions 
it :  Right  wheel. 

At  the  command  march,  the  pivot-guides  stand  fast  in  their 
places  and  the  platoons  wheel  to  the  right  on  a  fixed  pivot.  At 
the  command  halt,  given  when  the  marching  Hanks  arrive  near 
the  line,  the  subdivisions  halt;  the  instructor  places  himself,  fac- 
ing to  the  right,  on  the  prolongation  of  the  line  of  the  pivot-guides 
at  i he  point  where  the  marching  Hank  of  the  leading  subdivision 
is  to  re<t.  At  the  command  dress,  the  battery  dresses  up  to  the 
line  established  by  the  pivot-guides  and  instructor,  the  left  guide 
of  the  leading  subdivision  touching  the  breast  of  the  instructor 
with  the  left  arm;  the  instructor  superintends  the  alignment, 
and  gives  the  command  front  upon  its  completion.  At  the  com- 
mand guides  posts.  I  he  guides  return  to  their  places  in  line. 

If  marehing,  the  movement  is  executed  as  just  explained, 
except  that,  at  the  command  march,  the  guides  and  pivot-men 


16  MARCHING   MANCEUVRES. 

halt;  the  pivoj>men  mark  time  and  turn  in  their  places,  so  as  to 
conform  to  the  movement  of  the  marching  flank. 

Tl«  To  form  line  and  continue  the  march,  the  instructor 
commands :  3.  Forward*  4.  March,  5.  Guide  (right  or  left).  At 
the  command  forward,  the  pivot-guides  take  their  places  in  line. 

To  form  line  to  the  front  column  of  platoons. 

72.  Being  at  a  halt,  the  instructor  commands  :  1.  Eight  (or 
left)  front  into  line,  2.  March,  3.  Front. 

At  the  first  command,  the  chief  of  the  leading  platoon  com- 
mands :  1;  Forward,  2.  Guide  left;  the  other  chiefs  command  : 
Bight  oblique.  At  the  command  march,  repeated  by  all  the 
chiefs,  the  leading  platoon  advances  eighteen  yards,  when  its 
chief  commands:  1.  Platoon,  2.  Halt,  3.  Left,  4.  Dress;  the 
other  platoons  oblique  to  the  right  until  opposite  their  places  in 
line,  when  their  chiefs  command:  1.  Forward*  2.  MARCH,  3. 
Guide  left,  adding,  as  they  arrive  near  the  line :  3.  Platoon*  4. 
Halt,  5.  Left,  6.  Dress;  the  instructor  superintends  tin?  align- 
ment from  the  left  flank,  and  gives  the  command  front  upon  its 
completion. 

If  marching  in  quick  time,  the  movement  is  executed  as  just 
explained,  the  chief  of  the  leading  platoon  commanding  guide 
left,  if  the  guide  be  not  already  there. 

If  marching  in  quick  time  and  the  command  be  double  time, 
the  instructor  commands  :  Guide  left  immediately  after  the  com- 
mand march;  the  chief  of  the  leading  platoon  does  not  halt  it, 
but  cautions  it  to  advance  in  quick  time,  and  repeats  the  com- 
mand for  the  guide;  each  of  the  other  chiefs  repeats  the  com- 
mand double  time,  and,  when  his  platoon  is  about  to  arrive  in 
line,  commands:  1.  Quick  time,  in  time  to  add:  2.  March,  the 
instant  it  arrives  abreast  of  the  leading  platoon. 

If  marching  in  double  time,  the  chief  of  the  leading  platoon 
commands :  Quick  time  at  the  first  command,  and  repeals  the 
other  commands;  the  other  subdivisions  complete  the  movement 
as  before. 

To  form  column  of  platoons  from  column  of  files. 

?3.  The  instructor  commands  : 

1.  Platoons,  2.  Right  (or  left)  front  into  line,  3.  March,  4.  Bat- 
tery, 5.  Halt. 

At  the  command  march*  the  leading  guide  of  each  platoon 
moves  straight  to  the  front;  all  the  files  oblique  to  the  right 
until  opposite  their  places  iu  line,  when  each  marches  to  the 
front. 


MARCHING   MAXCBtfVBBS.  17 

The  leading  guide  of  each  platoon  moves  forward  until  the 
command  halt,  which  is  given  when  he  has  advanced  five  yards; 
the  other  men  halt  on  arriving  in  line  ;  each  guide  in  rear  places 
himself  on  the  right  of  the  front  rank  upon  the  arrival  of  the  last 
file;  the  leading  guide  having  halted,  each  chief  dresses  his 
platoon  to  the  left,  and  commands  :  Front  when  the  last  file 
is  aligned. 

If  the  command  be  double  time,  the  instructor  commands : 
Guide  left  (or  right)  immediately  after  the  command  march  ;  the 
leading  guide  of  each  platoon  moves  forward  in  quick  time ;  the 
other  men  oblique  in  double  time,  each  taking  the  quick  step 
and  dressing  to  the  left  upon  arriving  in  line;  the  rear-rank 
men  then  close  to  facing  distance. 

This  movement  is  not  executed  when  marching  in  double 
time. 

The  instructor's  command  is  right  (or  left)  front  into  line, 
according  as  the  column  of  tiles  is  left,  or  right,  in  front. 

?4«  The  column  of  tiles  is  right  in  front  when  the  front-rank 
men  are  on  the  left  of  their  rear-rank  men  ;  it  is  left  in  front 
when  the  front-rank  men  are  on  the  right  of  the  rear-rank  men. 

To  change  direction  in  column  of  platoons. 

T5.   Being  in  march,  the  instructor  commands : 

1.   Column  right  (or  left),  2.  MARCH. 

At  the  first  command,  the  chief  of  the  leading  platoon  com- 
mands :  Right  wheel;  at  the  command  march,  which  he  repeats, 
his  platoon  wheels  to  the  right  on  a  movable  pivot,  the  chief 
adding:  1.  Forward,  2.  March,  upon  the  completion  of  the 
wheel ;  the  other  platoons  march  squarely  up  to  the  wheeling 
point,  and  change  direction  by  command  of  their  chiefs  as  ex- 
plained for  the  first. 

?6.  In  wheeling  on  a  movable  pivot,  as  the  dress  is  always 
toward  the  marching  flank  without  command,  whenever  a  wheel 
is  executed  toward  the  side  of  the  guide,  each  chief,  upon  its 
completion,  cautions  his  platoon,  guide  right  or  guide  left,  ac- 
cording as  the  guide  was  right  or  left  before  the  wheel. 

K1.  In  changing  direction,  each  chief-of-platoon  faces  his 
platoon  while  wheeling,  and  sees  that  the  guide  takes  steps  of 
twenty-eight  or  thirty-three  inches,  and  the  pivot,  steps  of  nine 
or  eleven  inches,  according  to  the  gait. 

Column  Jut Jf  right  (or  half  left)  is  similarly  executed,  each 
chief  giving  the  preparatory  command  right  (or  left)  half  wheel. 

To  make  a  small  change  of  direction,  the  instructor  cautions : 
Incline  to  the  rigid  (or  left). 

2 


I 


18  MARCHING   MANOEUVRES. 

The  leading  guide  advances  his  left  shoulder  and  takes  two 
points  a  little  to  the  right  of  those  upon  which  he  was  marching, 
the  men  conforming  to  the  new  direction  of  the  guide. 

78*  To  put  the  column  of  platoons  in  march  and  change 
direction  at  the  same  time,  the  instructor  commands  : 

1.  Forward,  2.  Guide  {right  or  left),  3.  Column  right  (or  lefty, 

4.  March. 

To  face  the  column  of  platoons  to  the  rear,  and  to  march  to 

the  rear, 

79*  The  instructor  commands  : 

1.   Platoons  right  (or  left)   about,  2.  March,   3.  Battery,   4. 

Halt. 

At  the  command  march,  the  platoons  execute  an  about  on  a 
fixed  pivot;  at  the  command  halt,  each  chief-of-platoon  dresses 
his  platoon  to  the  left,  commands :  Front,  and  then  takes  his 
post. 

To  march  to  the  rear  after  wheeling  about,  the  instructor  com- 
mands : 

3.  Forward,  4.  March,  5.  Guide  {left  or  right). 

To  form  column  of  detachments  to  the  right  or  left. 

SO.  Being  in  line,  the  instructor  commands : 

1.  Detachments  right  (or  left),  2.  March. 

At  the  first  command,  the  gunner,  acting  as  left  guide  of  the 
battery,  falls  out  and  takes  his  place  in  rear  of  his  detachment ; 
at  the  command  march,  eacli  detachment  wheels  to  the  right  on 
a  fixed  pivot ;  upon  the  completion  of  the  wheel,  the  front  rank 
of  each  take  the  full  step  (28  inches);  the  rear  rank  shortens  the 
step  till  it  gains  the  distance  of  thirty-two  inches  from  the  front 
rank;  the  guide  and  dress  of  each  detachment  is,  without  fur- 
ther command,  towards  the  side  opposite  the  gunners,  i.  e.,  to- 
ward the  wheeling  flank;  the  leading  guide  prolongs  accurately 
his  line  of  march  by  choosing  successively  points  in  advance ;  the 
other  guides  preserve  with  care  the  trace,  the  step,  and  wheel- 
ing distance. 

The  gunners  march  one  yard  from  the  flank  of  their  respective 
detachments,  and  see  that  the  ranks  maintain  accurately  their 
alignments  and  distances. 

The  positions  of  the  officers,  first -sergeant,  gunners,  and 
trumpeters  are  as  prescribed  In  pars.  26  to  33. 


MARCHING  MANCBUVBBS.  19 

To  form  column  of  detachments  and  halt. 
8 1.  The  instructor  commands : 
1.  Detachments  right  (or  left),  2.  March,  3.  Batteri/,  4.  HALT. 

The  fourth  command  is  given  the  instant  the  front  rank  com- 
plete the  wheel ;  the  rear  ranks  fall  back  to  thirty-two  inches, 
and  all  the  ranks  dress,  without  further  command,  toward  the 
marching  flank. 

852.  In  all  wheelings  hy  detachments,  the  forward  march  is 
taken  upon  the.  completion  of  the  movement,  unless  the  com- 
mand halt  be  given.     This  rule  is  general. 

83.  In  column  of  detachments,  the  ranks  dress  toward  the 
flank  opposite  the  gunners.     This  rule  is  general. 

To  march  in  column  of  detachments  to  the  front  from  either  flank. 

84.  Being  in  line,  the  instructor  commands  : 

1.  Right  (or  left)  forward,  2.  Detachments  right  (or  left),  8. 

March. 

At  the  command  march,  the  right  detachment  moves  straight 
to  the  front,  with  the  guide  to  the  left;  its  rear  rank,  shortening 
the  step,  falls  back  to  thirty-two  inches;  the  other  detachments 
wheel  to  the  right  on  a  fixed  pivot;  the  second  detachment, 
when  its  wheel  is  nearly  completed,  wheels  to  the  left  on  a 
movable  pivot,  and  follows  the  first  detachment ;  the  other  de- 
tachments having  wheeled  to  the  right,  move  forward  and  wheel 
to  the  left  on  a  movable  pivot  on  the  same  ground  as  the  second. 

Being  in  column  of  detachments,  at  a  halt  or  marching,  to  change 
the  chief s-of platoons  and  gunners  from  one  flank  of  the  col- 
umn to  the  other, 

85.  The  instructor  commands  : 

1.  Officers  and  gunners  change  flank,  2.  MARCH. 

At  the  first  command,  the  officers  and  gunners  close  into  the 
flanks  of  the  column;  and,  at  the  command  march,  pass  quickly 
through  the  column  between  the  detachments. 

To  put  the  column  of  detachment  in  march,  and  to  halt  th$ 

column. 

86.  The  instructor  commands : 

1.  Forward,  2.  March,  and  1.  Battery,  2.  Hai/F. 


20  MARCHING  MANCEUVRE8. 

To  change  direction  in  column  of  detachments. 
Being  in  march,  the  instructor  commands : 

1.  Column  right  (or  left),  2.  Maboh. 

At  the  command  march,  the  leading  rank  wheels  on  a  movable 
pivot ;  the  wheel  being  completed,  this  rank  retakes  the  step  of 
twenty-eight  inches ;  the  otiier  ranks  move  forward  and  wheel 
on  the  same  ground. 

Column  half  right  (or  left)  is  similarly  executed. 

87.  To  put  the  column  of  detachments  in  march,  and  change 
direction  at  the  same  time,  the  instructor  commands : 

1.  Forward,  2.  Column  right  (or  left),  3.  March. 

To  march  the  column  of  detachments  to  the  rear, 

88.  The  instructor  commands : 

1.  Detachments  right  (or  left)  about,  2.  MARCH. 

The  detachments  wheel  about  on  a  fixed  pivot;  the  man  on 
the  marching  flank  of  the  rear  rank  of  each  detachment  pre- 
serves the  distance  of  thirty-two  inches  from  his  f ront-rank  man  ; 
the  man  on  the  pivot  flank  closes  up  to  his  front-rank  man, 
covering  him  during  the  wheel,  and  on  its  completion  falls  back 
to  thirty-two  inches;  the  chiefs  -  of  -  platoon  and  the  gunner* 
oblique  to  the  right  or  left  in  turning  about,  so  as  to  preserve 
their  proper  positions  with  reference  to  the  column. 

To  form  line  from  column  of  detachments. 

89.  To  the  rigid  or  left.  The  battery  being  at  a  halt,  or  march- 
ing, the  instructor  commands : 

1.  Detachment  right  (or  left\  2.  March,  3.  Guide  (right  or 
left) ;  or,  3.  battery,  4.  Halt,  5.  Left  (or  right),  6.  Dress,. 
7.  Front. 

At  the  command  march,  the  detachments  wheel  to  the  right 
on  a  fixed  pivot.  The  rear  rank  of  each  detachment  closes  to 
facing  distance  during  the  wheel,  except  when  executed  in  double 
time,  and  the  line  advances  on  the  completion  of  the  wheel. 

If  the  line  be  formed  towards  the  side  from  the  chiefs-of -pla- 
toon, they  close  to  the  flank  of  the  column  at  the»first  command, 
and,  at  the  command  march,  pass  quickly  through  the  column 
between  their  detachments;  the  gunners,  at  the  same  time,  in 
like  manner,  pass  to  the  other  side  of  the  column. 

When  the  command  halt  is  given,  the  instructor,  before  dress- 
ing the  battery,  places  the  leading  guide  on  the  line  of  the  pivot- 


MARCHING   MANOEUVRES.  21 

men,  and  at  a  distance  from  the  leading  pivot-man  sufficient  to 
admit  the  leading  detachment;  the  battery  is  then  dressed  on 
this  guide  and  the  pivot-men  of  the  detachments. 
90*    On  the  right  or  left.    The  instructor  commands : 

1.  On  the  right  (or  left)  into  line,  2.  MARCH,  3.  FRONT. 

At  the  command  march,  the  leading  detachment  wheels  to  the 
right  on  a  movable  pivot,  and  moves  forward,  dressing  to  the 
right;  the  other  detachments  march  a  distance  equal  to  their 
front,  beyond  the  wheeling  point  of  the  detachment  next  pre- 
ceding, wheel  to  the  right,  and  advance  as  explained  for  the 
first.  The  leading  detachment,  having  wheeled,  advances  five 
yards  and  is  halted  by  the  command:  1.  First  detachment,  2. 
Halt,  3.  Right  (or  left),  4.  Dress,  from  the  chief  of  its  pla- 
toon ;  at  the  fourth  command  it  dresses  to  the  right;  the  other 
detachments  halt  and  dress  successively  upon  arriving  in  line ; 
the  rear  rank  of  each  detachment,  upon  halting,  closes  to  facing 
distance.  The  instructor  places  himself  on  the  right  to  superin- 
tend the  movement,  and  after  the  last  detachment  dresses  gives 
the  command  front. 

At  the  eommand/rontf,  given  when  the  last  detachment  com- 
pletes dressing,  all  cast  their  eyes  to  the  front. 

The  chiefs-of-platoon  and  guunera  follow  up  the  movements 
and  take  their  positions  in  line  as  the  detachments  successively 
come  up  to  it.  If  the  movement  be  executed  on  the  side  opposite 
the  gunners,  each  takes  his  place  behind  the  detachment  by 
passing  in  front  of  the  one  next  succeeding  it. 

91.  To  the  front.  The  battery  being  at  a  halt,  the  instructor 
commands : 

1.  Right  (or  left)  front  into  line,  2.  March,  3.  Front. 

At  the  command  march,  the  first  detachment  moves  straight 
to  the  front,  dressing  to  the  left;  the  other  detachments  oblique 
to  the  right  until  opposite  their  places  in  line,  when  each  marches 
to  the  front.     As  soon  as  the  leading  detachment  has  advanced 
five  yards,  the  chief  of  its  platoon  commands:  1.  First  detach- 
ment, 2.  Halt,  3.  Left  (or  right),  4.  Dress;  at  the  fourth 
command  it  dresses  to  the  left ;  the  other  detachments  halt,  and 
lress  to  the  left  upon  arriving  in  line;  the  rear  ranks  close  to 
acing  distance  «ipon  halting.    The  gunner  who  is  the  left  guide 
f  the  battery  in  line  places  himself  on  the  flank  of  his  detach- 
lent  as  soon  as  it  halts  upon  reaching  the  line.     The  instructor 
•aces  himself  on  the  left  to  superintend  the  movement,  and 
ter  the  last  detachment  dresses  gives  the  command  front. 
92*  As  a  rule,  this  movement  is  made  towards  the  side  of 


22  MARCHING  MANOEUVRES. 

the  chief s-of-platoon ;  should  it  be  made  towards  the  opposite 
side,  the  chiefs  of  the  leading  and  last  platoon  take  their  posts 
in  line  by  passing  around  the  flanks  of  the  battery ;  the  chiefs  of 
the  other  platoons  pass  through  the  column  as  the  oblique  com- 
mences; at  the  same  time  all  the  gunners  pass  through  to  the 
opposite  flank. 

If  marching  in  quick  time,  the  leading  detachment  continues 
to  advance  until  halted,  as  before,  and  the  other  detachments- 
oblique,  at  the  command  march. 

If  marching  in  double  time,  or  in  quick  time,  and  the  com- 
mand be  double  time,  the  instructor  commands :  Guide  left  im- 
mediately after  the  command  march;  the  leading  detachment 
moves  to  the  front  and  continues  the  march  in  quick  time,  its 
rear  rank  closing  to  facing  distance;  the  other  detachments 
oblique  in  double  time,  each  taking  the  quick  time  and  dressing 
to  the  left  upon  arriving  in  line ;  the  rear  rank,  ou  arriving  in 
line,  closes  to  facing  distance. 

To  march  the  column  of  subdivisions  by  the  flank, 

93*  If  at  a  halt,  the  instructor  commands : 

1.  Right  (or  left),  2.  Face,  3.  Forward,  4.  March,  5.  Guide 

(right  or  left). 

94.  If  marching: 

1.  By  the  (right  or  left)  flank,  2.  March,  3.  Guide  (left  or 

right ). 

The  guides  of  the  subdivisions  preserve  proper  intervals,  and 
dress  on  the  guide  who  conducts  the  guiding  subdivision. 

95.  To  resume  the  original  direction,  the  instructor  com- 
mands : 

1.  By  the  left  (or  right)  flank,  2.  March;  and  for  platoons,  3. 

Guide  (right  or  left). 

To  halt  and  resume  the  original  front,  the  instructor  com- 
mands : 

1.  Battery,  2.  Halt,  3.  Left  (or  right),  4.  Face. 

To  oblique  in  column  of  subdivisions. 

96*  The  instructor  commands : 

1.  Eight  (or  left)  oblique,  2.  March. 

During  the  oblique,  the  subdivisions  preserve  their  parallel- 
ism; the  guide  of  each  subdivision  on  the  side  towards  which 


MARCHING   MANCEUVRES.  28 

the  oblique  is  made  is  the  guide  of  the  subdivision ;  the  guide  of 
the  leading  subdivision  is  the  guide  of  the  column.  The  guides 
keep  on  a  line  parallel  to  the  original  direction. 

97.  To  resume  the  direct  march,  the  instructor  commands: 

1.  Forward*  2.  March. 

The  guide  is,  without  indication,  on  the  side  it  was  previous  to 
the  oblique. 

If  the  oblique  be  executed  from  a  halt,  the  guide  is  announced 
upon  taking  the  direct  march. 

98.  The  batteiy  being  at  a  halt,  in  line,  or  in  column  of 
subdivisions,  to  march  it  a  short  distance  to  the  rear,  the  in- 
structor commands:  1.  Battery ;  2.  About,  3.  Face;  the  chief  s- 
of-detachment  and  the  gunner  acting  as  guide  step  into  the  rear, 
now  become  the  front,  rank ;  the  chiefs-of-platoon,  now  in  rear, 
remain  there. 

The  original  direction  is  resumed  by  again  passing  to  the  flank 
inarch,  or  at  once  by  the  commands :  1.  To  the  rear,  2.  March  ; 
or,  if  at  a  halt,  1.  Battery,  2.  About,  3.  Face;  the  guides  and 
chiefs-of-detachment  in  either  case  return  to  the  front  rank. 

To  form  column  of  files  from  column  of  subdivisions. 

99*  Being  at  a  halt,  the  instructor  commands : 

1.  Bight  (or  left),  2.  Face,   3.  Platoons  (or  detachments),  4. 
Column  left  (or  Column  right),  5.  MARCH. 

At  the  command  face,  all  face  to  the  right ;  at  the  command 
march,  each  subdivision  column  changes  direction,  and  Joins 
upon  the  one  which  precedes  it. 

If  marching,  the  instructor  commands : 

1.  By  the  right  (or  left)  flank,  2.  Platoons  (or  detachments),  3. 
Column  left  (or  Column  right),  4.  March. 

At  the  command  march,  each  subdivision  faces  to  the  right  in 
marching,  changes  direction,  and  joins  upon  the  one  which  pre- 
cedes it. 

In  both  cases,  if  the  movement  is  executed  from  column  of 
detachments  the  rear  rank  close  in  elbow  to  elbow,  with  the 
front  rank. 

The  route  step. 

lOO.  When  it  is  desired  to  give  freedom  and  ease  to  the  men 
i  marching,  the  instructor  commands : 

1.  Route  step,  2.  March. 

If  in  line  or  column  of  platoons,  the  rear  rank  falls  back  to 


24  MARCHING   MANCEUVRES. 

thirty-two  indies  from  the  front  rank ;  the  men  are  uot  required 
to  keep  silence,  nor  keep  the  step,  but  each  man  covers  the  tile 
in  his  front,  and,  if  armed,  carries  his  piece  at  will. 

To  resume  the  attention,  the  instructor  commands  :  1.  Battery. 
2.  Attention.  At  the  second  command,  the  rear  rank,  if  in 
line  or  column  of  platoons,  closes  to  facing  distance,  and  all  the 
men  take  the  step. 

The  battery  may  also  be  marched  at  rout  step  in  column  of 
files,  the  distance  between  files  being  increased  to  thirty-two 
inches.  On  resuming  the  attention,  the  leading  file  takes  the 
short  step  until  the  other  files  close  to  facing  distance. 

The  battery  in  rout  step  changes  direction  by  the  same  com- 
mands as  when  in  cadence  step. 

To  form  single  rank  from  double  rank. 

1©1.  For  special  purposes  it  may  be  desired  to  make  this 
formation. 
Being  in  line,  at  a  halt,  the  instructor  commands  : 

1.  Form  single  rank,  2.  Detachments  (right  or  left),  3.  MARCH. 

At  the  command  march,  all  the  detachments  wheel  to  the 
right;  the  front  rank  of  the  right  detachment,  upon  completing 
the  wheel,  continues  the  march  wit!)  its  guide  on  the  wheeling 
flank;  the  other  ranks  halt,  and  successively  resume  the  march 
when  at  wheeling  distance  from  the  rank  preceding  it ;  the  rear- 
most rank  having  its  distance,  the  instructor  commands  : 

1.  Detachment  left  (or  right),  2.  March,  3.  Battery*  4.  HALT, 
5.  Left  (or  right),  6.  Dress.  7.  Front  ;  or,  3.  Guide  {right 
or  left). 

102.  Marching  in  column  of  detachments,  to  form  single 
rank,  the  instructor  commands : 

1.  Form  single  rank,  2.  MARCH. 

At  the  second  command,  the  front  rank  of  the  leading  dotach- 
ment  continues  the  inarch  ;  the  other  ranks  halt,  and  successively 
resume  the  march  when  at  wheeling  distance;  the  rearmost 
rank  having  its  distance,  line  is  formed  as  before. 

103.  In  single  rank,  the  relative  positions  of  the  officers  and 
non-commissioned  officers  are  the  same  as  when  in  double  rank, 
and  the  battery  performs,  by  the  same  commands  and  means, 
all  the  movements  of  a  double  rank.  The  cannoneers  retain 
their  original  numbers. 

In  executing  the  rear  open  order,  the  gunners  step  hack  to  the 
line  marked  by  the  guides  for  a  supposed  rear  rank. 


MARCHING  MAN<BUVKB8.  26 

To  form  double  rank  from  single  rank. 

104.  Being  in  line,  at  a  halt,  the  instructor  commands: 

1.  Form  double  rank,  2.  Detachments  right  (or  left),  3.  MARCH. 

At  the  command  marclu  the  front  and  roar  rank  of  each  de- 
tachment wheels  separately  to  the  right;  the  leading  rank  halts 
the  instant  the  wheel  is  completed;  the  other  ranks  continue  the 
march  and  halt  successively,  each  rear  rank  upon  closing  to 
facing  distance  from  its  front  rank,  and  each  front  rank  when 
at  wheeling  distance  from  the  rear  rank  of  tin1  preceding  detach- 
ment. When  the  column  is  put  in  march,  the  rear  rank  of  each 
detachment  falls  back  to  thirty-two  inches  from  the  front  rank. 

In  forming  from  single  to  double  rank,  the  instructor  wheels 
the  detachments  to  the  right  or  left,  according  as  the  front-rank 
men  are  on  the  right  or  left  of  their  rear-rank  men. 

105.  Marching  in  column  of  detachments  at  single-rank  dis- 
tance, the  front-rank  men  of  each  detachment  in  front  of  their 
rear-rank  men,  to  form  double  rank,  the  instructor  commands  : 

1.  Form  double  rank,  2.  March. 

At  the  command  march,  the  leading  rank  of  the  first  detach- 
ment halts ;  the  other  ranks  continue  the  march,  each  halting  in 
the  manner  just  explained. 

To  march  to  the  pieces,  or  other  place  of  exercise, 

106.  'The  front,  in  connection  with  a  piece  of  artillery,  is  the 
direction  in  which  the  muzzle  points,  except  when  the  piece  is 
mounted  on  a  traveling  carriage  and  the  carriage  is  limbered 
up;  in  which  case  the  front  is  in  the  direction  in  which  the  pole 
points.  The  right  or  left  is  the  right  or  left  when  looking  towards 
the  front. 

The  battery  being  formed  for  drill,  as  prescribed  in  par.  37, 
the  instructor  wheels  it  into  column  of  detachment,  or  faces  it 
into  column  of  files;  to  the  right  if  he  is  to  approach  the  bat- 
tery on  the  left,  and  to  the  left  if  he  is  to  approach  it  on  the 
right.  The  column  is  directed  so  as  to  bring  the  detachments  as 
nearly  as  practicable  four  yards  in  the  rear  of  the  platforms  of 
the  pieces.  When  the  head  of  column  arrives  at  a  distance  of 
four  yards  from  the  left  or  right  of  the  battery,  the  instructor 
commands  :  Detachments  opposite  your  pieces. 

1st.  Column  of  files.  As  each  detachment  arrives  opposite  its 
piece,  it  is  halted  by  the  chief-of-detachment,  who  then  com- 
iiands : 

1.  Left  (or  right),  2.  Face,  3.  Right,  4.  Dress,  5.  Front. 


26.  MARCHING  MANOEUVRES. 

The  detachment  faces  to  the  piece,  and  immediately  the  gun- 
ner places  himself  by  the  side  of  the  left  front-rank  cannoneer; 
this  is  his  place  at  all  times  when  the  detachment  is  in  this  posi- 
tion at  the  piece. 

2d.  Column  of  detachments.  As  each  detachment  arrives  oppo- 
site its  piece,  ihe  chief-of-detachment  halts  it,  and  commands, 
according  as  the  battery  has  been  approached  on  its  loft  or  right  z 
1 .  Left  (or  right)  wheel,  2.  March,  3.  Detachment,  4.  HALT,  5. 
Right,  G.  Dress,  7.  Front;  he  then  takes  his  post  on  the 
right  of  the  front  rank. 

As  the  detachment  wheels,  the  gunner  takes  his  post  by  the 
side  of  the  left  front-rank  cannoneer. 

107.  The  centre  of  the  detachment  i3  four  yards  in  rear  of 
the  piece  or  centre  of  the  platform. 

Each  chief-of-platoon  places  himself  one  yard  in  rear  of  the 
centre  of  his  platoon,  or  at  such  other  place  as  he  can  best 
observe  his  detachments. 

To  take  posts. 
(Figure  4,  Plate  IL) 

108.  The  instructor  commands  : 

1.  Cannoneers  to  your  posts,  2.  March. 

At  the  first  command,  the  chief  of  each  detachment,  stepping 
two  yards  to  the  front  and  facing  his  detachment,  commands : 
1.  Eight,  2.  Face,  3.  To  your  posts  ;  the  detachment  having 
faced  at  the  command  of  its  chief,  the  gunner  steps  to  one  side, 
and  at  the  command  march  by  the  instructor,  repeated  by  the 
chiefs-of-detachment,  it  files  to  the  left,  the  two  ranks  separat- 
ing, the  rear  rank  marching  to  the  right  of  the  piece,  and  the 
front  rank  to  the  left  of  it.  As  each  man  arrives  at  his  post,  he 
halts  and  faces  the  piece,  Nos.  1  and  2  one  yard  from  the 
epai il i nent,  parapet,  or  scarp;  their  breasts  eighteen  inches  out- 
side of  the  carriage ;  the  remaining  numbers  and  the  gunner 
dressing  respectively  on  Nos.  1  and  2,  at  intervals  of  one  yard, 
except  that  between  Nos.  4  and  6  and  3  and  5  there  is  an  inter- 
val of  two  yards;  the  gunner  places  himself  in  the  interval 
between  Nos.  4  and  6. 

Willi  mortars,  Nos.  1  and  2  are  on  a  line  with  the  muzzle,  the 
remaining  number  and  the  gunner  being  as  before. 

The  chief-of-detachment  is  facing  the  piece,  and  two  yards 
in  rear  of  the  platform  or  rearmost  part  of  the  carriage;  while 
superintending  the  exercises,  he  goes  wherever  his  presence  is 
most  required. 


MARCHING   MANOEUVRES.  27 

109.  As  soon  as  the  cannoneers  are  at  their  posts,  the  in- 
structor commands : 

Take  equipments. 

This  is  executed  as  hereinafter  prescribed  for  each  kind  of 
piece. 

At  the  conclusion  of  the  exercises  tie  causes  the  implements 
and  equipments  to  be  replaced  as  hereinafter  prescribed  for  each 
case. 

To  rest. 
HO.  The  instructor  commands : 

I.  In  place,  2.  Rest;  or,  I.  Rest. 

The  cannoneers  lay  down  their  handspikes,  as  explained  it* 
par.  236. 

In  the  first,  case,  the  men  remain  at  their  posts ;  in  the  second,, 
they  may  leave  their  posts,  but  must  remain  near  the  piece. 

To  resume  the  exercise. 

111.  The  instructor  commands : 

1.  Battery ,  2.  ATTENTION. 

All  resume  their  posts  and  handspikes. 

To  change  posts. 

112*  The  instructor  commands  : 

1.  Change  posts,  2.  March,  3.  CALL  OFF. 

At  the  first  command,  the  cannoneers  lay  down  their  hand- 
spikes, place  their  equipments  on  the  parts  of  the  carriage  near- 
est them,  or  on  the  platform,  and  face  to  their  left.  At  the 
command  march,  each  cannoneer  advances  one  post;  No.  2,  pass- 
ing in  rear  of  the  piece,  takes  the  place  of  No.  1 ;  No.  1  of  No. 
3;  No.  3  of  No.  5,  and  so  on.  On  arriving  at  their  new  posts 
they  face  the  piece  and,  without  further  command,  take  the 
handspikes  and  equipments  belonging  to  them ;  at  the  third 
command,  they  call  off  according  to  their  new  numbers. 

To  leave  the  battery. 

113.  The  instructor  first  causes  the  equipments  to  be  re- 
laced,  as  hereafter  prescribed  for  each  case,  and  then  com- 
lauds: 

1.  Detachments  rear,  2.  March. 

At  the  first  command,  repeated  by  the  chief s-of-detachment,. 


J28  MARCHING  MANCEUVRES. 

the  cannoneers  upon  the  right  of  the  piece  face  to  their  left,  and 
those  upon  the  left  to  the  right;  at  the  command  march,  repeat- 
ed hy  the  chief  s-of -detachment,  they  march  to  the  rear,  the  rank 
with  even  numbers  closing  on  that  with  odd  numbers,  change 
direction  to  the  right  at  the  command  :  1.  Column  right,  2. 
March,  from  the  chief-of-detachment,  are  halted,  faced  to  the 
front,  and  dressed  to  the  right  by  him,  so  as  to  bring  the  centre 
-of  the  detachment  on  a  line  with  the  axis  of  the  piece,  or  oppo- 
site the  middle  of  the  platform,  and  four  yards  in  rear  of  it.  The 
gunner  takes  his  place  on  the  left  of  the  front  rank. 

To  reform  the  battery  and  leave  the  pieces, 

1st.  Into  column  of  files. 

114.  The  instructor  commands  : 

1.  Detachments  right  (or  left),  2.  Face,   3.   Close,  4.  MARCH. 

At  the  command  face*  the  detachments  face  to  the  right,  the 
gunners  taking  their  places  in  the  rank  of  file-closers,  and  at  the 
command  march,  repeated  by  all  the  chiefs-of-detachment,  (ex- 
cept the  leading  one,)  all  the  detachments  close  on  the  leading 
one,  which  stands  fast.  As  each  detachment  closes  up  to  the  one 
in  front  of  it,  it  is  halted,  by  its  chief,  who  then  takes  his  post  in 
front  of  the  leading  file  of  the  front  rank. 

2d.  Into  column  of  detachments. 

115.  To  form  column  of  detachments,  the  instructor  com- 
mands: 1.  Detachments  right  (or  left)  wheel.  2.  March,  3. 
Close  to  wheeling  distance,  4.  Guide  {right  or  left),  5.  March. 

At  the  second  command,  each  detachment  wheels  to  the  right 
and  is  halted  and  dressed  to  the  left  by  its  chief;  at  the  third 
command,  the  chief  of  the  leading  detachment  cautions  it  to 
stand  fast;  at  the  fifth  command,  all  the  detachments  in  rear  of 
the  first  step  off,  and  each  is  halted  by  its  chief  when  at  wheel- 
ing distance  from  the  preceding  detachment. 

The  column  is  then  marched  from  the  battery  by  the  com- 
mands and  means  heretofore  explained. 

Formation  of  a  Battalion. 

{Figure  5,  Plate  IT.) 

116.  When  two  or  more  batteries  form  together  in  line,  the 
first -sergeants  take  post  beside  and  on  the  right  of  the  front-rank 
■cannoneer  of  their  batteries ;  the  chiefs  of  the  right  detachments, 
stepping  back  for  that  purpose,  take  post  in  line  of  gunners  in 
rear  of  the  right  file  of  their  detachments ;  the  first-sergeants 


MARCHING   MANOEUVRES. 


29 


retain  habitually  this  position  during  all  battalion  manoeuvres, 
and  arc  the  guides  of  that  flank  of  their  batteries. 

117.  Gunners  acting  as  left,  guides  of  batteries,  except  the 
battery  on  the  left  flank,  fall  back  and  occupy  their  posts  in 
rear  of  their  detachments. 

118.  Batteries  form  without  intervals;  the  first-sergeant  of 
each,  except  the  right,  touching  the  left  front-rank  cannoneer 
of  the  battery  on  his  right. 

119.  The  trumpeters  of  all  the  batteries  are  united  and  take 
post  on  the  right  of  the  battalion  in  two  ranks,  the  left  of  the 
front  rank  twelve  yards  to  the  right  of  the  first-sergeant  of  the 
right  battery;  when  there  is  a  band,  they  are  as  provided  in 
par.  125. 

In  all  other  respects  the  several  batteries  have  the  formation 
given  in  pars.  24  to  36. 

120.  A  battalion  is  composed  of  two  or  more  batteries,  not 
exceeding  twelve.  When  there  are  more  than  twelve  batteries, 
they  are  formed  into  two  or  more  battalions,  the  batteries  of 
each  regiment  being  kept,  as  far  as  practicable,  together. 

121.  In  forming  the  line,  the  batteries  are  posted  from  right 
to  left,  according  to  the  following  table ;  the  numbers  indicate 
the  relative  rank  of  the  battery  commanders,  the  senior,  or  No. 
1,  being  on  the  right  of  the  Hue  : 


1 

3 

2 

1 

3 

4 

2 

1 

5 

3 

4 

2 

i 

.4 

3 

6 

5 

2 

i 

5 

7 

3 

4 

6 

2 

i 

5 

8 

3 

7 

4 

6 

2 

i 

6 

5 

8 

3 

9 

4 

7 

2 

i 

6 

4 

9 

3 

8 

5 

10 

7 

2 

i 

7 

9 

5 

10 

3 

11 

6 

8 

4 

2 

l 

7 

4 

10 

11 

3 

12 

6 

5 

9 

8 

2 

122.  Batteries  whose  captains  are  absent  are  posted  in  line- 
according  to  the  relative  rank  of  the  officers  present  in  command 

»f  them.  At  the  discretion  of  the  commanding  officer,  a  battery 
vhose  captain  is  absent  for  a  few  days  only  may  retain  its  place 
ccording  to  his  rank. 

123.  Batteries  are  designated  numerically  from  right  to  left 
"hen  in  line,  and  from  front  to  rear  when  in  column,  first  bat- 
ry,  second  battery r,  and  so  on. 


30  MARCHING   MANOEUVRES. 

The  designations  of  batteries  change  when,  by  facing  in  the 
opposite  direction,  the  left  becomes  the  right  of  the  line,  and  the 
rear  the  head  of  the  column. 

124.  When  a  battalion  is  provided  with  colors  there  will  be 
a  color-guard,  composed  of  a  color-sergeant  and  seven  corporals, 
which  is  posted  as  the  left  detachment  of  the  right  centre  battery. 
{Number  3  of  the  table.) 

'1  he  front  rank  is  composed  of  the  color-sergeant  and  the  three 
senior  corporals,  one  posted  on  his  right  and  two  on  his  left ;  the 
rear  rank  is  composed  of  the  four  remaining  corporals,  placed 
in  order  of  rank  from  right  to  left. 

The  color-sergeant  carries  the  national  color.  A  regimental 
oolor  (when  present)  is  carried  by  a  sergeant,  who  takes  the 
place  of  i  he  corporal  on  the  left  of  the  color-sergeant. 

The  color  is  to  be  carried  only  when  the  battalion  is  under 
arms  with  musket*. 

At  the  sounding  of  the  assembty  the  color-guard  forms  at  the 
appointed  place,  and  is  marched,  by  commands  of  the  color- 
sergeant,  to  the  place  where  the  color  is  kept.  The  color- 
sergeant  receives  the  color  and  faces  towards  the  guard;  the 
senior  corporal  commands :  1.  Present,  2.  Arms,  at  which  the 
guard  salutes  the  color;  the  corporal  then  commands:  1.  Carryy 
2.  Arms,  after  which  the  sergeant  takes  ins  position  in  the 
guard;  the  guard  is  then,  by  commands  from  the  sergeant, 
■marched  to  the  color-battery  on  its  parade-ground. 

On  returning  the  color  the  same  ceremonies  are  observed. 

The  color -bearer  carries  the  heel  of  the  color -lance  in  Its 
socket,  supported  at  the  right  hip;  the  right  hand  grasps  the 
stall' at  the  height  of  the  shoulder,  to  hold  it  steady.  The  color- 
bearer  salutes  with  the  color  as  follows  : 

(One.)  Slip  tiie  right  hand  along  the  staff  to  the  height  of  the 
eye;  lower  the  staffby  straightening  the  arm  to  its  full  extent, 
the  heel  of  the  lance  remaining  at  the  hip. 

(Two,)    Bring  back  the  lance  to  the  habitual  position. 

At  all  occasions  of  ceremony  the  color  is  without  its  case. 

When  marching  in  double  time,  the  color-bearer  grasps  the 
•color  to  the  lance,  raises  the  heel  from  the  socket,  and  allows 
the  color,  the  lance  sloping  to  the  rear,  to  rest  on  the  right 
shoulder. 

Posts  of  field  and  staff  officers. 

125.  The  following  is  for  a  full  regiment  of  twelve  batteries  ; 
lor  a  less  number  the  same  principles  are  observed  : 

{Figure  5,  Plate  II.) 

The  colonel  is  thirty  yards  in  front  of  the  line  of  captains, 


MARCHING  MANCBUVBES.  81 

opposite  the  centre  of  the  battalion.  This  distance,  as  also  that 
for  the  other  Held  officers,  is  reduced  as  the  front  of  the  battalion 
is  diminished. 

The  lieutenant-colonel  is  twelve  yards  in  front  of  the  line  of 
captain?,  and  opposite  the  centre  of  the  three  batteries  on  the 
right;  thv  first  major  occupies  a  like  position  with  reference  to 
the  three  left  batteries  of  the  battalion  ;  the  second  major  a  like 
position  with  reference  to  the  three  right  centre  batteries;  the 
third  major  a  like  position  with  reference  to  the  three  left  centre 
batteries. 

The  adjutant  is  in  line  with  the  chiefs-of-platoon,  and  three 
yards  outside  the  right  flank  of  the  battalion. 

Other  staff  officers,  in  the  order  of  rank  from  right  to  left,  am 
on  the  right  of  the  adjutant,  with  one  yard  interval  between 
each. 

The  sergeant-major  is  three  yards  to  the  left  of  the  front  rank 
of  the  battalion. 

Other  non-commissioned  staff  officers,  when  present,  are  on 
the  left  of  the  sergeant-major,  with  one  yard  interval  between 
each. 

The  band  is  formed  in  two  or  more  ranks,  with  intervals  be- 
tween tiles,  and  distances  between  the  ranks  sufficient  to  permit 
a  free  use  of  their  instruments. 

The  trumpeters  form  the  rear  ranks  of  the  band. 

The  band  is  posted  on  the  right  of  the  battalion,  the  left  of  its 
front  rank  twelve  yards  from  the  right  of  the  front  rank  of  the 
battalion. 

The  field  and  staff  officers  are  mounted  or  on  foot,  as  the  com- 
manding officer  may  direct. 

126.  When  the  battalion  is  in  column  on  the  march,  in  cam- 
paign, the  colonel,  lieutenant -colonel,  second  major,  and  staff 
officers  march  at  the  head  of  the  column  ;  the  other  two  majors 
and  the  non-commissioned  staff  at  the  rear;  the  baud  at  the 
head  or  rear,  as  the  commanding  officer  may  direct.  In  all  other 
cases,  when  the  line  is  broken  into  column,  whether  of  batteries, 
platoons,  or  detachments,  the  field  officers,  adjutant,  and  ser- 
geant-major take  post  on  the  flank  of  the  column  on  the  side 
next  to  the  wheeling  flank  of  the  subdivision  ;  the  colonel  about 
"thirty  yards  from  the  centre  of  the  column  ;  the  lieutenant-enl- 
">ne1  and  majors  six  yards  from  the  flank,  each  in  line  with  J  he 
itibdivision  in  front  of  which  he  was  posted  in  line;  the  adjut- 
ant and  sergeant-major  in  their  own  wings  abreast  of  and  three 
'aids  from  the  flank  of  the  leading  and  rear  subdivisions  of  the 
olumn. 

The  staff  officers  (excepting  the  adjutant)  wheel  to  the  right 


32  MARCHING   MANOEUVRES. 

(or  left)  and  place  themselves,  with  intervals  of  one  yard,  oppo- 
site the  centre  of  the  leading  subdivision,  and  six  yards  in  front 
of  the  leading  captain,  or  six  yards  in  rear  of  the  gunners  of  the 
last  subdivision,  according  as  the  Hue  has  been  broken  to  the 
right  or  left. 

The  non-commissioned  staff  (excepting  the  sergeant-major) 
occupy  a  similar  position  with  reference  to  the  other  extremity 
of  the  column. 

The  band  wheels  to  the  right  (or  left),  and  takes  post  in  front 
or  rear  of  the  column,  as  the  colonel  may  direct. 

In  column  of  files,  the  fields  staff,  and  non-commissioned  staff 
officers,  and  the  band,  are  as  if  each  had  faced  with  the  battal- 
ion. 

To  form  the  battalion, 

127.  The  batteries  being  formed  on  their  parade-grounds, 
adjutant's  call  is  sounded,  at  which  the  adjutant  and  sergeant- 
major,  the  latter  on  the  left,  each  followed  by  a  marker,  march 
to  the  battalion  parade-ground,  where  they  post  the  markers, 
facing  each  other  at  a  distance  apart  a  little  lesss  than  the  front 
of  a  battery  ;  the  adjutant  posts  the  marker  nearest  the  right  of 
the  line,  the  sergeant-major  the  one  nearest  the  left ;  each 
marker  holds  his  staff  in  front  of  him  ;  the  adjutant  and  sergeant- 
major  draw  swords,  face  about,  and  each  proceeds  battery  dis- 
tance towards  his  flank  of  the  line;  they  then  face  about  and 
cover  the  markers. 

The  color-battery  is  the  first  established,  and  is  conducted  by 
its  captain  so  as  to  arrive  from  the  rear,  parallel  to  the  line  of 
markers.  When  it  arrives  at  three  yards  from  the  line,  the  cap- 
tain halts  it;  dresses  it  to  the  left,  against  the  markers;  com- 
mands/Wwtf,  and  takes  his  post  in  front. 

The  batteries  of  the  right  wing  form  successively  from  left  to 
right,  each  being  brought  upon  the  line  and  dressed  to  the  left, 
as  explained  for  the  color-batter}1';  the  gunner  of  each  battery, 
acting  as  left  guide,  at  the  command  halU  returns  to  his  post  in 
rear  of  his  detachment;  at  the  same  time  the  right  guide  places 
himself,  facing  the  markers,  and  aligns  himself  on  them,  at  bat- 
tery distance  from  the  right  marker,  or  guide  in  front  of  him. 
The  first-sergeant  takes  the  place  of  thechief-of-detaehment  who 
has  stepped  out  to  mark  the  line.  The  adjutant  assures  the 
position  of  the  right  guides,  placing  himself  in  their  rear  as  they 
successively  arrive.  The  guides  retain  their  positions  on  the  line 
until  the  command  guides  posts  is  given. 

The  batteries  of  the  left  wing  form  successively  from  right  to 
left,  in  a  similar  manner,  and  are  dressed  to  the  right ;  the  left 


MARCHING   MANCEUVRES.  33 

instead  of  the  right  guides  place  themselves  on  the  Hue,  and  are 
assured  in  position  by  the  sergeant-major.  At  the  command 
halt,  the  first-sergeant  and  the  chief  of  the  right  detachment  take 
their  places,  as  per  par,  116. 

Both  wings  are  formed  simultaneously. 

To  enable  the  captains  fortress  their  batteries,  the  first-sergeants 
step  into  the  rear  rank,  each  resuming  his  place  in  the  front  rank 
as  soon  as  the  captain,. after  dressing  his  battery,  takes  his  post 
in  front. 

The  field  and  staff  and  non-commissioned  staff'  officers  take 
their  posts  as  the  battalion  is  formed.  The  colonel  faces  towards 
the  line. 

128.  Before  sounding  adjutant's  call,  the  hand  takes  a  posi- 
tion designated  by  the  adjutant,  and  marches  at  the  same  time 
as  the  batteries  to  its  position  in  line. 

Each  captain  commands  :  1.  Support,  2.  Arms,  as  soon  as  the 
captain  next  succeeding  him  in  his  own  wing  commands  front; 
the  flank  batteries  support  arms  as  soon  as  dressed. 

The  sergeant-major  having  assured  the  position  of  the  left 
guide  of  the  left  battery,  takes  his  post  on  the  left  of  the  line. 

129.  The  adjutant  having  assured  the  position  of  the  right 
guide  of  the  right  battery,  places  himself,  facing  towards  the  left 
of  the  line,  three  yards  in  front  of  his  post,  and  when  the  last 
battery  arriving  on  the  line  is  brought  to  support  arms,  com- 
mands :  1.  Guides,  2.  POSTS.  At  this  command,  the  guides  and 
markers  take  their  posts  in  line,  the  latter  stationing  themselves 
in  the  line  of  gunners  on  the  right  and  left  flanks  of  the  battal- 
ion ;  the  first-sergeants  step  a  pace  to  the  rear  to  permit  the 
guides  and  markers  to  pass  through  their  intervals,  after  which 
they  return  to  the  front  rank.  Tlie  adjutant  then  passes  along 
the  front  in  rear  of  the  chief s-of-platoon ,  to  the  centre  of  the 
line,  turns  to  the  right,  halts  midway  between  the  captains  and 
the  colonel,  faces  about,  brings  the  battalion  to  a  carry*  and  a 
present  arms,  resumes  his  front,  salutes  the  colonel,  and  reports : 
Sir !  The  battalion  is  formed. 

The  colonel  returns  the  salute  with  the  right  hand,  directs  the 
adjutant :  Take  your  post,  Sir !  draws  his  sword,  and  commands  : 
1.  Carry*  2.  ARMS. 

The  adjutant  faces  about,  and  returns  to  his  post  on  the  right, 
passing  in  rear  of  the  chief  s-of-platoon  of  the  right  wing. 
13©.  The  foregoing  is  the  habitual  formation  of  an  artillery 
tttalion  when  serving  as  artillery,  and  will  be  used  for  ocea- 
ns of  drill  and  ceremonies.  Where  battalion  movements 
come  necessary  or  desirable,  those  embraced  in  the  fct  School 
t  the  Battalion  "  [Infantry  Tactics,]  are  prescribed,  and 

3 


34  DEFINITIONS. 

will  be  executed  on  the  principles  therein  given,  substituting 
the  commands  detachments  and  battery  tor  "fours"  and  "com- 
pany "  wherever  they  occur. 

Other  differences  of  detail  will  suggest  themselves  from  the 
marching  drill  heretofore  given  in  this  work,  which,  it  is  under- 
stood, is  the  basis  of  movements  for  heavy  artillery  troops. 

The  skirmishing  manoeuvres  are  those  prescribed  in  Infantry 
Tactics,  substituting  commands  as  above. 

Chief s-of-detachment  and  gunners  remain  with  their  detach- 
ments in  all  deployments,  exercising  over  the  men  such  control 
as  will  insure  the  maximum  of  efficiency. 

Definitions. 
(Figure  1,  Plate  III.) 

131.  Cannon.  The  term  cannon  is  applied  to  all  heavy  fire- 
arms discharged  from  carriages,  in  contradistinction  to  small 
arms,  which  are  discharged  from  the  hand.  The  general  form 
of  cannon  is  that  of  a  truncated  cone,  the  largest  part  being  at 
the  breech,  around  the  seat  of  the  charge;  in  those  of  recent 
model,  the  exterior  elements  are  curves,  and  there  are  neither 
mouldings  nor  ornaments  on  the  piece. 

All  heavy  cannon  in  the  U.  S.  land  service  are  made  of  cast- 
iron  ;  those  pieces  having  greater  calibres  than  that  of  the  siege 
gun  are  cast  hollow,  being  cooled  from  the  inside  upon  the  prin- 
ciple introduced  by  Rodman. 

The  want  of  ductility  in  cast-iron  is  unfavorable  to  its  endu- 
rance under  high  vibratory  strains ;  and  as  the  ballistic  power 
demanded  of  ordnance  has  greatly  increased  of  late  years,  cast- 
iron  is  no  longer  much  used  for  forming  the  parts  immediately 
about  the  bore  of  heavy  rifled  guns,  some  other  metal  being  sub- 
stituted, the  molecules  of  which  accommodate  themselves  more 
readily  to  new  positions  when  under  strain. 

It  has  been  found  that  cast-iron  guns  are  greatly  improved  by 
tubing  them  with  some  ductile  and  strong  metal,  as  low  steel  or 
wrought-iron.  A  large  part  of  the  energy  that  the  powder  gas 
exerts  on  the  surface  of  the  bore  is  absorbed  in  expanding  the 
tube,  and  that  which  finally  reaches  the  cast-iron  being  much 
reduced  in  amount,  and  also  spread  over  a  surface  relatively 
much  greater  than  that  of  the  bore,  is  largely  within  the  limits 
of  safety  for  the  comparatively  brittle  envelope.  The  ductile 
metal  of  the  tube  also  cushions  the  cast-iron  against  the  effects 
of  severe  vibration  and  shock. 

Guns  thus  constructed  have  great  power  of  endurance,  and 


DEFINITIONS.  85 

when  put  to  extreme  test  it  has  been  found  that  the  cast-iron 
casing  does  not  burst  explosively,  but  cracks  and  gives  way 
without  violence. 

The  10-inch  smooth-bore  is  converted  into  an  8-inch  rifle,  and 
the  15-inch  smooth-bore  into  a  12-inch  rifle,  by  this  method. 
(See  8-inch  rifle,  'par,  319.) 

132.  The  bore  is  the  interior  portion  of  the  cannon,  intended 
to  receive  the  charge  and  projectile.  It  is  bored  out  with  the 
greatest  accuracy  as  to  straightness,  diameter,  and  smoothness. 

133.  The  muzzle  is  the  mouth  of  the  bore.  The  face  is  the 
terminating  plane  at  the  muzzle,  perpendicular  to  the  axis  of 
the  bore. 

134*  The  axis  of  a  cannon,  or  of  the  bore,  is  the  central  line 
of  the  bore. 

135.  The  trunniotis  are  two  solid  cylindrical  arms  project- 
ing from  the  sides  of  the  cannon  for  the  purpose  of  supporting  it 
on  its  carriage.  They  are  placed  at  or  near  the  centre  of  grav- 
ity, on  opposite  sides  of  the  piece,  with  their  axes  in  the  same 
line,  at  right  angles  to  the  axis  of  the  piece,  and  in  the  same 
plane  with  that  axis. 

136*  The  rimbases  are  the  shoulders  forming  the  junction 
between  the  trunnions  and  the  piece.  They  serve  to  strengthen 
the  trunnions,  and,  being  terminated  by  planes  at  right  angles 
to  the  axes  of  the  trunnions,  prevent  the  piece  from  moving 
sideways  on  the  carriage. 

13TT.  The  breech  is  the  solid  mass  of  metal  behind  the  bot- 
tom of  the  bore. 

138.  The  base  of  the  breech  is  the  rear  surface  of  the  breech. 

139.  The  cascable  is  the  projection  in  rear  of  the  breech.  It 
is  composed  of  the  knob  and  the  neck;  the  latter  unites  the 
knob  to  the  base  of  the  breech. 

In  heavy  guns  of  recent  model  the  cascable  is  quite  rudiment- 
ary, while  in  mortars  it  is  entirely  wanting. 

The  object  of  the  cascable  is  to  facilitate  handling  the  piece 
when  mounting,  dismounting,  and  transporting  it. 

14©.  The  body  of  the  piece  is  that  part  in  rear  of  the  trun- 
nions. 

141.  The  chase  is  that  part  of  the  piece  in  front  of  the  trun- 
nions. 

142.  The  vent  is  the  channel  through  which  fire  is  commu- 
nicated to  the  charge  in  the  bore.  Its  diameter  is  two-tenths  of 
an  inch,  and  it  is  generally  situated  in  the  plane  passing  through 
the  axis  of  the  bore,  perpendicular  to  the  axis  of  the  trunnions. 

It  is  at  right  angles  to  the  axis  of  the  bore,  and  enters  the  lat- 
ter at  a  distance  from  the  bottom  of  one-fourth  of  the  diameter 


36  DEFINITIONS. 

of  the  bore.  In  mortars  and  sea-coast  guns  there  are  two  vents, 
each  situated  in  a  plane  perpendicular  to  the  axis  of  the  trun- 
nions, at  equal  distances  on  each  side  of  the  axis  of  the  piece, 
and  distant  therefrom  one-fourth  of  the  diameter  of  the  bore. 
The  one  on  the  left  is  bored  entirely  through ;  the  other  stops 
short  an  inch  from  the  bore.  When  the  open  vent  becomes  too 
much  enlarged  by  wear  for  further  use,  it  is  closed  with  melted 
zinc  and  the  other  bored  out.  Each  one  should  endure  at  least 
live  hundred  service  rounds. 

In  some  pieces,  a  vent-piece,  usually  of  pure  soft  copper, 
through  which  the  vent  has  been  bored,  is  screwed  into  the 
breech.     This  is  called  bushing  the  vent. 

143.  The  bottom  of  the  bore  is  the  interior  termination  of  the 
bore,  and  is  a  semi-ellipsoid. 

144.  The  chamber,  or  powder-chamber,  of  a  piece  is  that  part 
of  the  bottom  of  the  bore  in  which  the  powder  is  lodged  at  the 
time  of  firing.  Formerly  all  mortars,  howitzers,  and  shell  guns 
throwing  projectiles  of  comparatively  large  size  with  small 
charges,  were  provided  with  chambers  smaller  than  the  bore, 
for  the  purpose  of  confining  the  powder  into  a  small  space. 
In  the  present  system  the  chamber  is  omitted  from  all  pieces 
except  the  flank  casemate  howitzer  and  the  Coehorn  mortar, 
which  are  pieces  of  old  pattern  still  retained  in  service. 

It  has  been  found  experimentally  that  it  is  advantageous, 
especially  with  rifles,  to  have  the  bore  enlarged,  instead  of  di- 
minished, at  the  seat  of  the  charge.  This  gives  an  air  space 
which  diminishes  the  pressure  upon  the  walls  of  the  piece  with- 
out diminishing  the  velocity  of  the  projectile. 

The  object  sought  for  in  the  construction  of  modern  artillery 
is  to  secure  great  ballistic  energy  for  the  purpose  of  destroying 
heavy  armor.  This  is  secured  by  using  heavy  projectiles  pro- 
pelled with  great  velocity.  But  to  obtain  this  result  without 
undue  pressure  on  the  piece,  the  character,  as  to  density,  shape, 
and  size  of  the  grain,  of  the  powder  introduced  is  such  as  to 
cause  it  to  burn  progressively,  with  an  increasing  volume  of  gas, 
thus  keeping  up  the  pressure  against  the  projectile  as  it  moves 
along  the  bore,  without  causing  an. undue  pressure  upon  the 
bore  at  any  point.  This  gives  a  total  effect  against  the  project- 
ile greater  than  was  obtained  from  any  of  the  older  and  more 
violent  powders. 

The  charge  of  powder  is  much  greater  than  formerly;  this 
requires  an  increased  length  of  bore,  but  it  has  been  found 
that  an  enlarged  chamber,  with  suitable  charge,  is  equivalent  to 
increase  of  length  of  bore,  and  that  by  these  means  the  desired 
velocity  is  obtained  without  unduly  increasing  the  length  of  the 


DEFINITIONS.  37 

piece,  or  of  producing  a  strain  which  it  is  not  capable  of  stand* 
iug. 

145.  The  dispart  is  the  difference  between  the  semi-diameter 
of  the  piece  at  the  muzzle  and  at  the  thickest  part,  usually  near 
the  vent. 

146.  A  gun  is  a  cannon  intended  to  throw  projectiles,  either 
solid  or  hollow,  with  large  charges  of  powder,  for  the  purpose 
of  attaining  great  range,  accuracy,  and  penetration.  It  is  dis- 
tinguished from  other  cannon  by  greater  length  and  weight. 

147.  A  howitzer  is  a  cannon  employed  to  throw  hollow  pro- 
jectiles with  comparatively  small  charges  of  powder.  It  is 
shorter  and  lighter  than  guns  of  the  same  calibre.  The  small- 
ness  of  the  charge  and  the  great  size  of  the  projectile  adapt  it- 
ad  van  tageously  to  ricochet  firing. 

148.  A  mortar  is  a  short  and  comparatively  light  cannon, 
employed  to  throw  hollow  projectiles  at  great  angles  of  eleva- 
tion. It  is  intended  to  product;  eftect  by* the  force  with  which 
the  projectiles  descend  upon  the  object,  and  by  the  force  with 
which  these  explode.  The  great  curvature  of  their  fire  gives 
them  power  of  reaching  objects  behind  works  which  would  be 
secure  from  direct  fire. 

149.  Cannon  are  classified  as  smooth-bore  and  rifles.  In  the 
former,  spherical  projectiles  are  used ;  in  the  latter,  elongated. 

150.  A  rifle  is  a  gun  having  a  number  of  spiral  grooves, 
called  "  rifles,"  cut  into  the  surface  of  the  bore.  These  grooves 
are  for  the  purpose  of  giving  to  the  projectile  a  rotary  motion 
around  its  longitudinal  axis.  The  portions  of  the  bore  between 
the  grooves  are  called  "lands";  these,  in  the  United  States 
service,  are  generall^v  of  about  the  same  width  as  the  grooves  or 
a  rifles." 

The  object  of  the  rotary  or  u rifle"  motion  is  to  increase  the 
range  of  the  projectile  by  causing  it  to  move  through  the  air  in 
the  direction  of  its  length,  or  least  resistance,  and  to  give  in- 
creased accuracy  by  distributing  the  principal  causes  of  devia- 
tion around  its  axis  of  rotation. 

The  projectiles  for  rifle-cannon  are  generally  made  of  cast- 
iron,  with  a  ring  or  cup  around  the  base,  made  of  bronze,  or 
some  other  metal  capable  of  expansion.  The  projectile  enters 
the  bore  freely  when  loading,  but  the  pressure  of  the  discharge 
expands  the  ring  or  cup  and  forces  the  latter  into  the  grooves, 
causing  the  projectile  in  its  outward  motion  to  follow  the  grooves, 
thus  imparting  to  it  the  desired  rotary  motion. 

151.  Twist  is  a  term  denoting  the  inclination  of  the 
apooves  to  the  axis  of  the  bore.  If  the  angle  of  inclination  be 
equal  at  all  points,  the  twist  is  said  to  be  uniform. 


88  DEFINITIONS. 

If  the  angle  increases  from  the  breech  to  the  muzzle,  the 
twist  is  called  increasing;  if  the  reverse,  decreasing. 

The  twist  is  measured  by  the  length  of  bore  corresponding  to 
a  single  revolution  of  the  spiral.  In  practice,  it  means  the  dis- 
tance passed  over  by  the  projectile  while  making  one  revolution 
about  its  axis,  and  is  expressed  in  feet. 

152.  Windage  is  the  space  left  between  the  bore  of  the  piece 
and  its  projectile.  It  is  measured  by  the  difference  of  their 
diameters,  and  is  expressed  in  hundredths  of  an  inch.  Windage 
is  necessary  in  order  to  make  allowance  for  the  bore  becoming 
foul  from  firing;  for  the  mechanical  impossibility  of  having  all 
projectiles  of  the  exact  size;  and  when  sabots  are  used,  to  give 
room  for  the  tin  straps  securing  them.  It  facilitates  loading, 
and  diminishes  the  danger  of  the  piece  bursting.  Windage 
increases  slightly  with  the  calibre  ;  it  is  much  less  for  rifle  than 
for  smooth-bore  guns. 

153*  Calibre  is  the  diameter  of  the  bore.  It  is  expressed  in 
inches,  except  for  pieces  of  old  pattern,  when  it  is  expressed  in 
terms  of  the  weight  of  a  solid  cast-iron  ball  of  the  diameter  of 
the  bore. 

154.  Preponderance  is  the  excess  of  weight  of  the  part  of  the 
piece  in  rear  of  the  trunnions  over  that  in  front.  It  is  expressed 
by  the  lifting  force,  in  pounds,  which  must  be  applied  at  the 
cascable  to  balance  the  piece  upon  the  trunnions. 

It  is  useful  only  for  pieces  mounted  on  travelling  carriages,  to 
keep  them  steady  in  transportation.  For  all  other  pieces  of  re- 
cent model  the  axis  of  the  trunnions  intersects  the  axis  of  the 
piece  at  the  centre  of  gravity,  thus  enabling  the  piece  to  be  ele- 
vated and  depressed  with  greater  ease.  The  discharge  does  not 
sensibly  change  the  position  of  the  piece  before  the  projectile 
leaves  the  bore. 

The  life  of  a  piece  is  the  number  of  rounds  that  it  will  stand 
before  becoming  unserviceable.  Cast-iron  guns  become  unsafe 
after  1,000  rounds. 

155*  Direct  or  horizontal  fire  is  where  the  piece  is  discharged, 
having  but  a  small  angle  of  elevation,  and  the  projectile  strikes 
the  object  without  touching  the  intermediate  ground. 

156*  Curved  or  vertical  fire  is  where  the  piece  is  discharged, 
having  a  great  angle  of  elevation,  as  are  mortars,  and  the  pro- 
jectile effects  its  work  chiefly  by  the  force  of  its  fall. 

15T.  Ricochet  fire  is  where  the  projectile  strikes  the  ground 
or  water  and  rebounds.  Projectiles  will  ricochet  upon  ground 
of  ordinary  firmness  when  the  angle  of  fall  does  not  exceed  10°; 
or  upon  water,  at  4°  or  5°. 

158.  Rolling  fire  is  where  the  axis  of  the  piece  is  parallel,  or 


DEFINITIONS.  39 

nearly  so,  with  the  ground  or  water,  and  the  projectile  rebounds 
over  the  surface  in  a  succession  of  ricochets. 

159.  Plunging  fire  is  where  the  object  fired  at.  is  situated 
below  the  piece. 

160.  The  point  of  fall  is  the  point  first  struck  by  the  pro- 
jectile. 

161.  The  angle  of  fall  is  the  angle  made,  at  the  point  of  fall, 
by  the  tangent  to  the  trajectory  witli  a  horizontal  line  in  tin* 
plane  of  fire.  It  is  always  greater  than  tiie  angle  of  elevation  of 
the  piece. 

162*  The  elevation  of  a  piece  is  the  inclination  of  its  axis 
above  the  horizon.  It  is  measured  by  the  angle  included  be- 
tween the  axis  of  the  bore  and  the  horizontal  line  in  the  plane 
of  fire  at  the  muzzle.    It  is  expressed  in  degrees. 

163*  The  depression  of  a  piece  is  the  reverse  of  its  elevation. 

164.  Range  is  the  horizontal  distance  from  the  muzzle  of  a 
piece  to  the  point  where  the  projectile  first  strikes. 

165*  Extreme  range  is  the  distance  from  the  piece  to  the  point 
at  which  the  projectile  is  brought  to  a  state  of  rest. 

Greatest  range  of  a  piece  is  the  farthest  distance;  to  which  it 
will  throw  a  projectile,  the  piece  being  mounted  on  its  appropri- 
ate carriage.  All  ranges  are  expressed  \\\  yards.  In  ah\  the 
maximum  range,  under  ordinary  circumstances,  is  obtained  from 
an  angle  not  far  from  34°. 

166.  Velocity  is  the  rate  of  motion  of  a  projectile.  It  is  ex- 
pressed in  feet  for  the  space  which  the  projectile  would  pass  over 
in  one  second  of  time,  supposing  it  to  have  a  uniform  rate  of 
motion  during  this  second. 

Initial  velocity,  or,  more  properly,  muzzle  velocity,  is  the  velocity 
at  the  muzzle  of  the  piece. 

Remaining  velocity  is  the  velocity  at  any  other  point  of  its  flight. 

Terminal  velocity  is  the  velocity  with  which  it  strikes  the  ob- 
ject. 

167.  Energy.  This  term,  when  used  in  connection  with  a 
projectile,  means  the  resistance  it  is  capable  of  overcoming  at 
the  time  of  striking  an  object.  The  resistance  overcome  is  the 
work  performed,  and  is  made  manifest  by  the  crushing  effect  of 
the  blow,  or  by  the  penetration  of  the  projectile.  It  implies 
both  pressure  and  motion,  and  is  expressed  in  foot  pounds, 
which,  for  convenience,  are  reduced  to  tons  of  2,240  pounds 
each.  It  is  the  living  force  of  mechanics,  expressed  mathemat- 
ically by     w  v2 

— s 5  nl  which  w=  weight  of  projectile  in  pounds; 

r=velocity  of  projectile  in  feet ; 
gr=gravity,  which,  in  the  latitude  of 
New  York,  is  equal  32.16. 


40  DEFINITIONS. 

To  apply  this  formula,  suppose  a  projectile  weighing  500 
pounds  strikes  the  side  of  an  ironclad  with  a  velocity  of  1,000 

feet,  we  have  \™*T^==7773631.8  foot  pounds;   by  dividing 

2240,  gives  3470.35  foot  tons  as  the  force  or  energy  of  the  blow. 

It  has  been  ascertained  by  experiment  that  the  resistance  of- 
fered by  armor  plates  to  penetration  by  a  given  weight  of  pro- 
jectile, the  energy  of  which  is  constant,  vanes  directly  as  the 
diameter  or  circumference  of  the  projectile ;  hence,  in  order  to 
find  the  penetrative  power  of  a  shot,  it  is  customary  to  divide  its 
energy  by  the  number  of  inches  in  its  circumference,  and  when 
projectiles  are  compared  in  this  way  they  can  be  classed  as  re- 
gards their  power  of  penetration.  It  will  be  seen  that  because 
a  si  lot  has  great  energy  it  does  not  necessarily  have  great  pene- 
trative power,  the  latter  depending  so  largely  on  its  diameter. 

For  obtaining  the  penetration  in  wrought-iron,  Captain  INo- 
ble's  formula  is  used ;  which  is — 

W  V2 

Z=  452617  xd   in  which 

3=number  of  foot  tons  per  inch  of  the  projectile's  circum- 
ference, 
d=diameter  of  projectile  in  inches, 
a=1.384, 
gssdepth  of  penetration. 

168.  The  line  of  metal  is  the  profile  cut  from  the  upper  sur- 
face of  the  piece  by  a  vertical  plane  passing  through  the  axis  of 
the  bore. 

(Fig.  1,  Plate  IV.) 

169.  The  natural  line  of  sight  is  the  right  line  passing 
through  the  highest  point  of  the  line  of  metal  at  the  muzzle, 
and  the  highest  point  of  the  same  line  in  rear  of  the  trunnions. 
'  170.  An  artificial  line  of  sight  is  the  right  line  containing 
the  guiding  points  of  the  sights. 

171.  The  line  of  fire  is  the  axis  of  the  bore  prolonged  in  the 
direction  of  the  muzzle. 

172.  The  plane  of  fire  is  the  vertical  plane  containing  the 
line  of  fires. 

173.  The  angle  of  fire  is  the  angle  included  between  the 
line  of  fire  and  horizon. 

J  74.  The  plane  of  sight  is  the  vertical  plane  containing  the 
line  of  sight.  It  may  be,  but  is  not  necessarily,  either  coincident 
or  parallel  with  the  plane  of  fires. 

1 75.  The  trajectory  is  the  curved  line  traced  by  the  project- 
ile in  its  passage  through  the  air;  it  lies  wholly  below  the  line 


GUNPOWDER.  41 

of  fire.  In  nearly  all  pieces,  the  natural  line  of  sight  cuts  the 
trajectory  at  two  points;  the  first  point  is  near  the  muzzle,  and 
the  second  farther  to  the  front. 

1*76.  Point-blank  and  point-blank  range  are  terms  formerly 
supposed  to  possess  great  importance  in  gunnery. 

The  point-blank  is  the  point  at  which  the  line  of  sight  inter- 
sects the  trajectory  the  second  time ;  or,  more*  practically  speak- 
ing, it  is  that  point  which,  being  aimed  at,  is  struck  by  the  pro- 
jectile. 

The  natural  point-blank  corresponds  to  the  natural  line  of 
sight  when  this  line  is  horizontal,  and  the  distance  of  this  point 
from  the  muzzle  is  called  the  point-blank  range. 

An  artificial  point-blank  is  one  corresponding  to  an  artificial 
line  of  sight. 

lTTI.  Deviation  is  when  the  projectile  does  not  move  strictly 
in  the  plane  of  fire,  but  inclines  to  the  right  or  left  of  it.  Wind 
blowing  across  the  line  of  fire  is  one  great  cause  of  deviation. 

178.  Drifts  or  derivation,  is  the  deviation  peculiar  to  rifle 
projectiles,  the  divergence  being  on  the  side  towards  which  the 
grooves  twist.  It  is  a  constantly  increasing  divergence  from  the 
plane  of  fire,  and  is  allowed  for,  in  aiming,  by  means  of  a  lateral 
motion  given  to  the  rear  sight.     (See  par.  3i9.) 

1*99.  Recoil  is  the  running  back  of  the  carriage  after  dis- 
charge. The  space  passed  over  after  the  gun  is  fired  is  also 
termed  the  recoil ;   it  is  expressed  in  feet. 

The  directrix  is  the  centre  line  in  the  plane  of  fire  of  an  em- 
brasure or  platform. 


AMMUNITION. 

Gunpowder. 

ISO.  Gunpowder  is  the  agent  employed  in  modern  warfare 
to  propel  projectiles  from  cannon  and  small  arms,  aud  gener- 
ally as  the  bursting-charge  of  projectiles ;  for  the  explosion  of 
mines  ;  blasting  purposes,  &c.  It  is  a  mechanical  mixture  giv- 
ing light,  heat,  and  gas  in  the  combustion  or  chemical  union  of 
its  ingredients. 

Explosion  is  a  phenomenon  arising  from  the  sudden  enlarge- 
ment of  the  volume  of  a  body;  as,  in  the  case  of  gunpowder,  a 
solid  body  is  rapidly  converted  into  a  gas  many  times  its  volume. 
If  the  body  is  confined  in  a  limited  space  and  exploded,  great 
heat  is  developed  and  a  vast  expansion  or  propelling  force  pro- 
iuced,  the  volume  of  gas  being  many  times  greater  than  that  of 
he  powder. 


42  GUNPOWDER. 

Tn  the  United  States  service,  gunpowder  is  obtained  from 
private  manufacturers.  It  is  distinguished  by  granulation ;  irreg- 
ular, as  musket,  mortar,  cannon,  and  mammoth;  regular,  as  cubic- 
al, and  the  molded  powders,  i,  e„  pellet,  hexagonal,  and  prismatic 
(perforated  hexagonal  prisms).  In  all  of  these,  the  proportion  of 
the  ingredients  are  the  same;  they  differ  only  in  the  size  and 
shape  of  grain,  density,  and  details  of  manufacture. 

Musket  powder  is  used  for  small  arms;  mortar  for  field  guns; 
cannon  for  light  siege  guns,  and  the  larger-grained  and  special 
powders  for  heavjr  sea-coast  guns. 

Note.— Special  powders  are  now  being  experimented  with  for 
both  field  and  siege  guns. 

Materials, 

The  materials  required  are  potassium  nitrate  (nitre),  charcoal, 
and  sulphur.  They  should  be  of  the  greatest  possible  purity  to 
insure  excellence  of  quality  and  guard  against  accidents  in 
manufacture.  The  proportions  by  weight  of  the  ingredients 
used  in  the  United  States  service  powder  are:  jff  nitre;  }f| 
charcoal ;  10  sulphur. 

It  is  essential  to  the  successful  and  uniform  manufacture  of 
powder  that  the  ingredients  should  be  procured  in  their  rough 
state,  and  be  refined  and  prepared  for  use  at  the  factory.  This  is 
also  necessary  as  a  security  against  accidents  at.  the  mills.  All 
foreign  matter  must  be  carefully  excluded,  and  every  precaution 
taken  against  their  introduction  in  handling  and  moving  the 
refined  materials. 

General  qualities. 

Gunpowder  should  be  of  an  even-sized  grain,  angular  and 
irregular  in  form,  without  sharp  corners,  and  very  hard.  When 
new,  it  should  leave  no  trace  of  dust  when  poured  on  the  back 
of  the  hand,  and  when  flashed  in  quantities  of  ten  grains  on  a 
clean  plate  it  should  leave  no  bead  or  foulness.  It  should  give 
the  required  initial  velocity  to  the  ball,  and  not  more  than  the 
maximum  pressure  on  the  gun,  and  should  absorb  but  little 
moisture  from  the  air. 

A  compact  shape  of  grain,  approaching  the  cube  or  sphere,  is 
desirable.  Elongated  flat  scales  are  objectionable.  The  number 
of  grains  in  several  weighed  samples  should  be  counted. 

Size  of  grain. 

The  size  of  the  grain  is  tested  by  standard  sieves  made  of  sheet 
brass  pierced  with  round  holes.  Two  sieves  are  used  for  each 
kind  of  powder:  Nos.  1  and  2  for  musket,  3  and  4  for  mortar,  5 
and  6  for  cannon,  and  7  and  8  for  mammoth  powder.  (Figs,  2 
and  3,  Plate  IV.) 


GUNPOWDER.  48 

Diameter  of  holes  for  musket  powder,  No.  1,  0.03  in.;  No.  2» 
0.06  in. 

Diameter  of  holes  for  mortar  powder,  No.  3,  0.10  in.;  No.  4. 
0.25  in. 

Diameter  of  holes  for  cannon  powder.  No.  5.  0.25  in.;  No.  0» 
0.5  in. 

Diameter  of  holes  for  mammoth  powder,  No.  7,  0.75  in.;  No. 
8,  0.9  in. 

Hexagonal, ")  Dimensions  of  these  powders  vary  with  the  calibre 
Cubical,  V  of  the  gun  in  which  they  are  used,  and  have  not  as 
Prismatic.  J     yet  been  definitely  determined  upon  in  our  service. 

Specific  gravity. 

The  specific  gravity  of  gunpowder  varies  from  1.65  to  1.8.  It 
is  important  that  it  should  be  determined  with  accuracy.  Alco- 
hol, and  water  saturated  with  saltpetre,  have  been  used  for  this 
purpose;  but  they  do  not  furnish  accurate  results.  Mercury 
only  is  to  be  relied  upon. 

Hardness  is  tested  by  breaking  the  grains  between  the  fingers,, 
and  is  judged  of  only  by  experience. 

Muzzle,  or  initial  velocity. 

This  is  determined  by  any  of  the  electro-ballistic  machine* 
available ;  the  Boulonge"  chronograph  is  one  of  the  simplest  and 
most  generally  used  for  proof  of  powder.  For  a  full  description 
and  use  of  the  instrument,  see  Ordnance  Memoranda,  No.  25. 

Strain  upon  the  gun. 

This  is  determined  by  the  Rodman  pressure-gauge.  For  de- 
scription and  use  of  the  instrument,  see  Ordnance  Memoranda,. 
No.  25. 

Determination  of  moisture  and  resistance  to  moisture. 

The  amount  of  moisture  in  powder  is  determined  by  drying 
samples  in  an  oven  with  a  water  bottom. 

The  powder  is  subjected  to  heat  as  long  as  it  loses  weight,  the 
loss  indicating  the  percentage  of  moisture  driven  off.  Oil  being 
removed  from  the  oven  it  should  be  transferred  at  once  to  per- 
fectly clean,  dry,  air-tight  weighing  bottles. 

The  ability  to  resist  moisture  is  determined  by  subjecting 
samples  which  have  been  dried  to  exposure,  first  in  open  air, 
then  in  a  hygroscope  containing  a  solution  of  nitre  at  100°  cooled 
to  80°  Fahr. 

The  hygroscope  is  an  air-tight  box  in  which  the  powder  i* 


44  GUNPOWDER. 

subjected  to  a  damp  atmosphere  at  a  uniform  temperature  for 
24  hours. 

The  powder  to  be  tested  is  placed  in  circular  cups  of  copper 
with  fine  wire-gauze  bottoms,  affording  free  access  of  moisture 
to  all  parts  of  the  sample  under  test.  The  percentage  of  gain 
is  determined  by  weighing  the  powder  in  carefully-prepared 
bottles  on  opening  the  hygroscope.  A  careful  record  is  kept  of 
the  barometer,  hj'grometer,  external,  and  maximum  and  mini- 
mum internal  thermometers. 

Incorporation, 

On  breaking  the  grains,  a  fine  uniform  ashen-gray  color 
throughout  should  appear;  the  grain  texture  should  be  close, 
without  white  specks  even  wheu  magnified.  For  "flashing"  on 
glass  or  porcelain  plates,  the  powder  should  be  in  small  conical 
heaps.  Small  copper  measures  for  fine-grain  powders,  inverted 
on  the  plates,  keeps  the  heap  nearly  the  same  at  each  trial.  If 
the  incorporation  is  good,  only  smoke  marks  remain  on  the 
plate  after  flashing;  if  bad,  specks  of  undecomposed  nitre  and 
sulphur  will  form  a  dirty  residue.  The  test  requires  experience 
to  insure  success. 

Inspection  report. 

The  report  of  inspection  should  show  the  place  and  date  of 
fabrication  and  of  proof,  the  kind  of  powder  and  its  general 
•qualities,  as  the  number  of  grains  in  100  grs. ;  its  specific  grav- 
ity;  whether  hard  or  soft,  round  or  angular,  of  uniform  or  irreg- 
ular size;  whether  free  from  dust  or  not;  the  initial  velocities 
And  pressures  per  square  inch  obtained  in  each  fire ;  the  amount 
of  moisture  absorbed ;  and,  finally,  the  height  of  the  barometer 
And  hygrometer  at  the  time  of  proof. 

Marks  on  the  barrels. 

Each  barrel  is  marked  on  both  heads  (in  white  oil-colors,  the 
bead  painted  black)  with  the  number  of  the  barrel,  the  name  of 
the  manufacturer,  year  of  fabrication,  and  the  kind  of  powder, 
-cannon,  mortar,  or  musket,  <fcc,  the  mean  initial  velocity,  the 
pressure  per  square  inch  on  the  pressure-piston,  and  density. 
Each  time  the  powder  is  proved,  the  initial  velocity  is  marked 
below  the  former  proofs,  and  the  date  of  the  trial  opposite  it. 
Each  barrel  contains  100  pounds. 

SPECIAL    POWDERS. 

181.  For  some  years  it  has  been  a  recognized  fact  that  the 
Ignition,  combustion,  and  explosive  effect  of  gunpowder  depend, 


GUNPOWDER.  4& 

in  a  great  degree,  on  the  size,  shape,  and  density  of  the  grain, 
and  that  guns  of  different  calibres  require  for  their  most  efficient 
service  powders  differing  in  these  features,  in  order  to  secure  the 
best  results.  The  rapid  increase  in  weight  of  projectiles  with 
the  increase  in  calibre  of  guns,  and  the  comparatively  smaller 
power  of  resistance  of  the  guns,  renders  it  necessary  that  the 
rate  of  combustion  of  the  charge  be  regulated  so  as  to  reduce 
the  strains  on  the  guns  as  much  as  possible,  while  at  the  same 
time  preserving  high  initial  velocity  to  the  projectile,  thus  ren- 
dering practicable  the  use  of  the  heaviest  guns,  projectiles,  and 
charges. 

The  amount  of  gas  evolved  at  the  first  instant  of  inflammation 
and  combustion  is  measurably  controlled  by  the  size  and  form  of 
grains,  offering  a  lesser  surface  of  ignition,  and  the  increased 
density,  offering  greater  resistance  to  the  penetration  of  the  hot 
gases  through  the  grains,  graduates  its  rapidity  of  burning.  The 
form  of  grain  affecting  the  amount  of  surface  exposed  to  com- 
bustion— that  shape  which  offers  a  comparatively  small  surface 
at  the  first  instant  of  ignition,  increasing  progressively — is  theo- 
retically the  best. 

Experiments  have  settled  the  important  part  played  by  pow- 
ders suited  in  the  above  qualities  to  the  guns  in  which  they  are 
to  be  used,  and  have  led  to  the  adoption  of  large-grain  powders 
in  heavy  guns,  resulting  in  the  production,  among  the  best,  of 
mammoth,  pebble,  cubical,  hexagonal,  and  perforated  prismatic 
powders.     (Figs.  4,  5,  6,  7,  Plate  IV.) 

Hexagonal  powder. 

This  powder  has  been  found  to  give  the  best  results  when 
used  in  pieces  of  heavy  calibre.    The  uniform  size  of  grain,  and 
their  polyhedral  shape,  insure  great  uniformity  in  position  and 
size  of  the  interstices  in  the  make-up  of  the  cartridge ;  this  in- 
sures, with  a  uniform  density  of  grain,  a  high  degree  of  uniform- 
ity in  pressures  and  velocities  from  given  charges  of  powder  and 
weights  of  projectiles.    The  powder  used  is  composed  of  United 
States  standard  proportions  of  the  ingredients,  with  a  specific 
gravity  of  1.7511.     Its  shape  and  dimensions  are  given  on  Plate 
IV,  Figs.  8,  9. 
The  proportions  of  the  ingredients  of  hexagonal  powder  con- 
orm  to  the  United  States  standard,  and  up  to  the  completion  of 
ie  incorporation  in  the  wheel  mill,  its  manufacture  is  like  that 
I  ordinary  powder. 

Mealing.  The  wheel  mill  cake  is  revolved  in  a  cylinder  of  wire- 
ove  cloth,  with  wooden  balls,  until  it  is  mealed. 
Pressing.  The  mealed  powder  is  then  carefully  pressed  be- 


46  GUNPOWDER. 

tween  horizontal  metallic  plates  or  dies.  The  powder  comes 
•out  in  a  sheet  or  cake  of  polyhedral  granules  united  along  their 
vertical  edges,  the  dies  being  nearly  perfect  dodecahedrons. 

Graining.  The  press-cake  is  passed  between  rollers  armed 
with  brass  cutting  teeth  at  an  angle  of  from  60°  and  120°  to  the 
axis,  which  cut  the  cake  into  granules,  their  cross-section  being1 
almost  hexagonal,  whence  the  powder  derives  its  name. 

The  powder  is  then  sent  to  the  glazing-mill  and  glazed ;  after 
which  it  is  brushed  and  dried.  The  powder  is  now  minutely 
examined,  its  specific  gravity  taken,  and  a  count  made  of  the 
granulation  ;  a  variation  of  two  granules  to  the  pound  is  enough 
to  condemn  the  powder,  the  granulation  being  72  to  the  pound. 
It  is  packed  in  barrels  in  the  usual  manner,  and  is  fired  in  car- 
tridge-bags as  other  powder. 

Mammoth  powder. 

This  powder  is  formed  by  breaking  up  mill  cake.  Exact  uni- 
formity of  size  and  shape  of  grains  does  not  therefore  exist.  The 
average  granulation  is  85  to  the  pound.    (Fig.  3,  Plate  IV.) 

Prismatic  powder. 

This  variety  is  formed  by  pressing  mealed  powder  into  prisms. 
The  hexagon  is  usually  adopted,  as  it  offers  a  good  shape  for 
piling,  and  the  angles  are  sufficiently  obtuse  to  prevent  spawl- 
ing  at  the  edges.  In  order  to  insure  uniform  and  progressive 
•combustion,  each  prism  is  perforated  with  a  small  hole  through 
its  axis;  formerly  several  holes  were  pierced. 

Cubical  powder. 

This  powder  is  of  a  regular  cubical  grain,  being  formed  by 
•cutting  press-cake  in  two  directions  at  right  angles  to  each  other. 
Each  grain  is  0.75  inch  in  size.  The  granulation  is  about  72  to 
the  pound.     (Fig.  4,  Plate  IV.) 

It  is  important  to  observe  that  the  proper  kind  of  powder  is 
used  in  the  guns  for  which  intended. 

182.  The  system  of  classification  in  use  in  the  Navy  differs 
somewhat  from  that  employed  in  the  Army.  The  hexagonal, 
cubical,  and  mammoth  are  about  the  same;  but  Navy  rifle  cor- 
responds nearly  to  Army  cannon,  and  the  Navy  cannon  is  the 
nearest  equivalent  to  Army  mortar. 

In  exchanging  powder  with  the  Navy,  it  is  necessary  to  ob- 
serve these  distinctions. 

Powder  barrels  should  never  be  opened,  except  when  required 
for  use,  as  grains  of  powder  falling  between  the  staves  would 


PROJECTILES.  47 

prevent  their  being  tightened.    Samples  must  be  taken  from 
the  bung. 

183.  For  ordinary  examination,  the  flashing  test,  heretofore 
mentioned,  is  a  ready  way  of  ascertaining  whether  tiie  powder 
is  of  good  quality  and  in  good  condition. 

If  powder  has  been  much  damaged  by  damp  it  will  be  caked, 
and  a  close  inspection  will  generally  detect  a  white  appearance 
on  the  grains,  due  to  nitre  having  been  dissolved  and  deposited 
in  crystals  on  the  surface. 

Powder  sometimes  becomes  caked  by  being  tightly  packed  in 
cartridges,  or  for  want  of  being  rolled  when  in  barrels.  It  will 
then  readily  crumble  into  its  original  grains  by  being  pressed  in 
the  hand  ;  but  if  the  grains  break  or  appear  friable,  the  powder 
is  unfit  for  service. 

This  latter  characteristic  indicates  that  the  caking  has  resulted 
from  dampness,  and  is  to  be  carefullj'  distinguished  from  the 
former. 

Pressure. 

184.  The  pressure  of  gunpowder,  when  fired  in  its  own  space, 
is  placed  at  about  95,000  pounds  to  the  square  inch.  When,  how- 
ever, the  powder  gas  expands  in  t\\e  bore  of  the  gun,  though  the 
proportion  of  the  products  of  combustion  are  the  same,  the  ten- 
sion is  greatly  less. 

185.  Cartridge-bags  are  sacks  for  containing  charges  of  pow- 
der when  put  into  the  piece.  They  should  be  made  entirely  from 
either  woolen  or  silken  stuff;  the  fabric  should  be  soft,  and 
closely  woven,  to  prevent  the  powder  from  sifting  through. 
The  seams  should  be  sewed  with  woolen  yarn  or  silk. 

Projectiles. 

186*  Projectiles  for  the  U.  S.  artillery  service  are  made  of 
cast-iron,  a  material  combining  in  a  greater  degree  than  any 
other  the  essential  qualities  of  hardness,  strength,  density,  and 
cheapness. 

Projectiles  are  classified  as  spherical  and  elongated.  The  first 
are  used  exclusively  in  smooth-bore  guns  ;  the  second  in  rifles. 

They  are  further  classified,  according  to  their  structure  and 
mode  of  operation,  as  solid,  hollow,  and  case-shot. 

18T.  Solid  projectiles  produce  their  effect  from  impact  alone, 
and  as  they  can  be  fired  with  the  greatest  charge  that  the  piece 
will  bear,  are  used  when  great  range,  accuracy,  and  penetration 
are  required.  They  are  the  only  projectiles  that  can  be  used 
with  effect  against  very  strong  walls,  or  armor-plated  vessels. 


48  PROJECTILES. 

Under  the  head  of  hollow  projectiles  are  included  shells  for 
guns,  howitzers,  and  mortar?. 

188.  Shells  have  less  strength  to  resist  shock  from  the  dis- 
charge of  the  piece  and  from  impact ;  they  are  therefore  gen- 
erally fired  with  smaller  charges  of  powder  than  solid  shot. 
The  weight  of  a  shell  is  generally  about  two-thirds  that  of  a 
solid  shot  of  the  same  calibre.  They  are  charged  with  mortar 
powder,  which,  exploding  with  violence,  produces  great  destruc- 
tion to  both  animate  and  inanimate  objects. 

The  principal  parts  of  a  shell  are  : 

First.  The  cavity,  used  to  hold  the  bursting  charge ;  or  burst- 
ing charge  and  incendiary  composition,  when  the  intention  is  to 
destroy  by  setting  fire  to  objects. 

Second.  The  fuse-hole,  which  is  used  for  inserting  the  charge, 
and  to  hold  the  fuse  which  communicates  fire  to  it. 

Spherical  shells  have  two  small  shallow  holes,  one  on  each  side 
of  the  fuse-hole,  into  which  are  inserted  the  shell-hooks  when 
loading.    These  holes  are  called  ears. 

Shells  for  mortars,  being  fired  with  lighter  charges  than  those 
for  guns,  have  less  thickness  of  metal. 

Spherical  shells  for  guns  are  reinforced  on  the  inside,  around 
the  fuse-hole,  to  prevent  the  fuse-plug  from  being  driven  in  by 
the  force  of  the  discharge.  This  reinforce  serves,  in  some  meas- 
ure, to  compensate  for  the  loss  of  weight  on  that  side  of  the  shell 
caused  by  the  fuse-hole,  thus  rendering  the  shell  more  accurate 
in  flight. 

189.  Case-shot  is  a  projectile  similar  to  a  shell,  but  with 
much  less  thickness  of  metal.  It  is  filled  with  leaden  bullets, 
which  are  secured  against  moving  loosely  about  by  having  their 
interstices  filled  with  melted  sulphur.  Through  the  fuse-hole, 
a  hole  is  bored  into  this  mass  of  bullets  and  sulphur  sufficient  to 
contain  a  bursting  charge.  This  projectile  is  intended  only  for 
use  against  troops.  The  fuse  is  so  regulated  as  to  burst  the  shell 
a  short  distance  in  front  of  the  object,  when  the  bullets  and 
fragments,  separating,  move  forward  in  a  sheaf  form,  and  pro- 
duce effect  as  from  musketry. 

The  charge  for  case-shot  should  be  only  sufficient  to  rupture 
the  case. 

190.  Elongated  projectiles  are  used  exclusively  for  rifle  guns, 
and,  like  the  spherical,  may  be  either  solid  or  hollow.  There 
are  in  service  various  patterns,  each  known,  generally,  by  the 
name  of  the  inventor.  They  all,  however,  have  a  general  re- 
semblance to  each  other,  and  consist  of  a  cylindrical  body  sur- 
mounted by  a  conoidal  head.  To  the  base  is  attached  a  ring  or 
cup  of  some  softer  metal,  which,  expauding  from  the  force  of 


PBOJBCTILES.  49 

the  discharge,  enters  the  grooves  of  the  piece  and  causes  the  pro- 
jectile to  take  a  rotary  motion  about  its  axis. 

The  fuse-hole,  which  is  in  the  pointed  end,  is  coincident  with 
the  axis.    The  fuse-plug  is  screwed  into  the  fuse-hole. 

The  most  approved  pattern  is  known  as  the  Butler  projectile, 
(Fig.  1,  Plate  F,)  the  sabot  of  which  consists  of  a  bronze  ring 
screwed  upon  the  base.  In  this  ring  an  annular  groove  is  cut; 
the  gas  from  the  charge  acting  on  this  channel? m*  forces  the 
exterior  lip  into  the  grooves  of  the  bore,  while  the  interior  is 
forced  still  tighter  upon  the  body  of  the  projectile,  thus  prevent- 
ing it  from  stripping. 

191*  A  cored  shot  is  an  elongated  projectile  having  a  cavity 
in  the  body  of  it.  This  cavity  is  for  the  purpose  of  throwing  the 
centre  of  gravity  towards  the  front  end  of  the  projectile,  thus 
insuring  greater  steadiness  of  flight. 

The  hollow  projectiles  are  either  shells  or  case-shot,  both  of 
which,  in  their  construction  and  use,  are  similar  to  those  hereto- 
fore described  for  smooth-bore  guns. 

Rifle  projectiles  have  a  length  of  two  to  three  times  their 
diameter,  depending  upon  the  pattern,  and  whether  solid  or 
hollow,  the  latter  being  generally  the  longest. 

192.  A  canister  is  a  projectile  consisting  of  a  hollow  tin  cyl- 
inder filled  with  cast-iron  or  leaden  balls,  which  vary  in  size 
and  number  with  the  kind  and  calibre  of  piece.  The  cylinder  is 
closed  at  the  bottom  with  a  thick  cast-iron  plate,  and  at  the  top 
by  one  of  sheet  iron.  The  balls  are  packed  in  with  dry  sawdust. 
Canister  is  not  effective  at  a  greater  distance  than  400  yards, 
and,  with  the  exception  of  flank  howitzers,  is  but  little  used  for 
heavy  artillery. 

193.  Grape-shot.  A  stand  of  grape  is  composed  of  nine  cast- 
iron  balls,  disposed  in  three  layers  of  three  balls  each.  They 
are  held  together  by  two  circular  iron  plates,  united  by  a  bolt 
passing  through  their  centres.  Around  this  bolt  the  balls  are 
held  by  two  iron  rings.  The  plates  have  a  diameter  correspond- 
ing to  the  calibres  of  the  gun  in  which  the  grape  is  to  be  used. 
The  size  of  the  balls  depends,  likewise,  upon  the  calibre  of  the 
gun. 

Grape  is  not  fired  from  rifle  guns,  and  has  but  limited  use  for 
those  of  smooth-bore ;  the  modern  musket  and  Gatling  being 
nuch  more  effective  than  either  canister  or  grape. 

194.  A  carcass  is  a  spherical  shell,  having  three  additional 
loles,  of  the  same  dimensions  as  the  fuse-hole,  pierced  at  equal 
listances  apart  in  the  upper  hemisphere  of  the  shell.    The  shell 

filled  with  a  composition  which  burns,  with  intense  power, 
om  eight  to  ten  minutes,  and  the  flame,  issuing  from  the  holes, 
4 


50  FUSES. 

flres  whatever  is  combustible  within  reach.  It  is  used  in  bom- 
bardments for  setting  fire  to  shipping,  magazines,  camps,  &c. 

When  the  prepared  carcass  is  not  to  be  had,  a  common  shell, 
either  spherical  or  elongated,  may  be  substituted  by  placing  in 
the  bottom  of  it  a  bursting  charge  contained  iu  a  bag;  over  this, 
carcass  composition  is  driven  until  the  shell  is  nearly  filled  ;  four 
or  five  strands  of  quick-match  are  then  inserted,  and  secured  by 
driving  more  composition  upon  them.  These  shells,  after  burn- 
ing as  a  carcass,  explode. 

Port-fire  composition  is  suitable  for  filling  them. 

195.  Afire-ball  is  a  projectile  of  an  oval  shape,  formed  of  a 
sack  of  canvas  tilled  with  combustible  composition,  whicti,  in 
burning,  emits  a  bright  flame.  It  contains  a  loaded  shell,  and 
is  used  for  lighting  up  the  enemy's  works.  It  is  fired  from  a 
mortar. 

Fuses. 

196.  A  fuse  is  tiie  contrivance  for  igniting  the  charge  of  a 
hollow  projectile,  after  it  has  left  the  piece,  upon  being  fired. 

They  are  divided  into  four  classes,  viz.:  the  time-fuse,  the 
percussion-fuse,  the  concussion-fuse,  and  the  combination-fuse. 

191.  The  time-fuse,  now  used  for  heavy  artillery,  is  com- 
posed of  a  paper  case  inclosing  a  column  of  compact  composi- 
tion, which  is  ignited  by  the  flame  from  the  charge  in  the  piece. 
It  burn3  for  a  certain  time,  at  the  end  of  which  it  communicates 
the  flame  to  the  charge  in  the  projectile.  The  paper  case  is  made 
slightly  conical  to  insure  a  close  fit  and  to  prevent  it  from  being 
driven  through  and  into  the  projectile.  It  is  inserted,  at  the 
time  of  loading  the  piece,  into  a  metal  or  wooden  fuse-plug  pre- 
viously driven  or  screwed  into  the  fuse-hole  of  the  projectile. 
The  composition  lias  the  same  ingredients  as  gunpowder,  the 
proportions  being  varied  to  suit  the  required  rate  of  combustion. 
To  insure  ignition,  it  is  primed  at  the  larger  end  with  rifle  pow- 
der. They  are  furnished  from  arsenals  in  water-proof  packages, 
each  package  being  marked  with  the  number  of  seconds  required 
for  the  burning  of  the  fuse ;  this  time  varies  from  two  to  twenty 
seconds  per  inch.  The  paper  case  is  graduated  into  seconds, 
which  enables  the  fuse  to  be  cut  to  a  length  corresponding  to 
any  intermediate  time.  All  fuses  of  this  kind  are  of  the  same 
diameter  and  are  two  inches  in  length. 

When  it  is  to  be  used  for  ricochet  tiring,  especially  over  water, 
a  plug,  known  as  the  water-cap  fuse-plug,  is  used.  This  is  con- 
structed to  prevent  the  burning  composition  from  being  extin- 
guished when  the  projectile  strikes,  and  consists  of  a  brass  plug 


PRIMERS.  51 

firmly  driven  or  screwed  into  the  fuse-hole  of  the  projectile ;  the 
paper  fnse  is  inserted  at  the  time  of  loading  the  piece,  after 
which  a  water-cap  is  screwed  into  the  plug. 

The  water-cap  is  of  brass,  and  is  perforated  with  a  crooked 
channel,  filled  with  mealed  powder;  the  mealed  powder  com- 
municates fire  to  the  paper  fuse,  and  the  angles  of  the  channel 
break  the  force  of  the  water  or  dirt.  The  top  of  the  cap  has  a 
recess  filled  with  a  priming  of  mealed  powder,  covered  by  a  pro- 
tecting disk  of  lead  or  paper,  which  is  pulled  off  immediately 
before  inserting  the  projectile  into  the  piece.  For  security 
against  accidental  ignition,  a  small  leaden  plug  is  placed  in  the 
inner  end  of  the  fuse-plug,  where  it  remains  until  it  is  driven 
out  by  the  shock  from  the  discharge  of  the  piece. 

Fuse-plugs  for  mortar  shells  are  generally  turned  from  some 
hard  wood  ;  these  are  made  to  fit  closely  by  rasping  them  off  to 
the  exact  size. 

The  paper  time-fuse  is  used  for  either  smooth-bore  or  rifle 
pieces. 

198.  The  percussion-fuse  is  used  only  for  rifle  projectiles, 
mid  is  ignited  by  the  striking  of  the  point  of  the  shell  against  an 
object.  There  are  many  varieties  of  this  fuse,  all  consisting, 
essentially,  of  a  brass  or  pewter  fuse-plug  containing  a  plunger. 
This  plunger  does  not  move  in  its  place  until  the  sudden  arrest- 
ing of  the  shell,  by  striking,  causes  it  to  break  its  fastening,  and, 
by  its  inertia,  is  driven  against  a  priming  of  fulminate,  which, 
exploding,  communicates  flame  to  the  charge  of  the  shell. 

199.  The  concussion-fuse  is*  made  to  operate  by  the  shock 
of  the  discharge  of  the  piece.  There  are  also  many  varieties  of 
this  kind  of  fuse,  all  of  which  are  composed  essentially  of  a 
plunger,  which,  by  its  inertia,  when  the  shell  starts  to  move  in 
tlie  bore,  breaks  its  fastenings,  and,  striking  against  a  priming 
of  fulminate,  explodes  it  and  communicates  fire  to  a  time-fuse 
inclosed  in  the  same  fuse-plug.  The  time-fuse  is  cut  or  set  to 
barn  the  required  time;  it  then  communicates  flame  to  the 
charge  in  the  shell/ 

Concussion-fuses  are  seldom  used  except  for  rifle  projectiles. 

The  combination-fuse  is  one  combining  the  principle  of  action 
of  the  three  former.  There  are,  also,  a  great  variety  of  this  kind 
M  fuse,  all  of  which  are  more  or  less  complicated. 

Primers. 

200.  The  friction-primer  is  a  device  for  communicating  Are 
rough  the  vent  to  the  charge  in  the  piece.  It  is  composed  of 
o  brass  tubes  soldered  together  at  right  angles.    The  shorter 


52  SABOTS. 

tube  contains  a  small  quantity  of  friction  composition,  in  contact 
with  which,  and  contained  also  in  the  short  tube,  is  a  serrated 
wire,  which  wire  is  doubled  at  its  other  extremity  into  a  loop 
forming:  an  e3'e  for  the  hook  of  the  lanyard;  the  long  tube  is 
filled  with  rifle  powder,  and  has  its  lower  extremity  closed  with 
wax.    (Fig.  2,  Plate  V.) 

The  long  tube  is  inserted  in  the  vent;  a  pull  upon  the  lanyard 
disengages  the  serrated  wire,  which,  by  its  friction  upon  the 
composition,  causes  the  latter  to  ignite,  and  thus  communicating 
fire  to  the  rifle  powder  in  the  long  tube,  explodes  the  cartridge 
in  the  piece. 

The  charge  of  rifle  powder  has  sufficient  force  to  pass  the 
flame  through  the  longest  vent  and  penetrate  several  thicknesses 
of  cartridge-cloth. 

(Fig.  3,  Plate  V.) 

201.  The  electric-primer  is  an  invention  for  firing  cannon  by 
means  of  electricity.  It  consists  of  the  long  tube  of  the  friction- 
primer  split  at  one  end  to  receive  a  short  but  larger  piece  of  brass 
tube,  to  which  it  is  soldered.  The  larger  piece  incloses  a  cylin- 
drical piece  of  hard  wood,  slotted  midway  of  its  length  and  per- 
forated at  each  end  to  receive  short  pieces  of  copper  wire,  which 
are  connected  across  the  slot  by  a  coiled  piece  of  fine  platinum 
wire.  The  outer  ends  of  the  copper  wires  project  a  few  inches 
to  connect  the  wires  of  the  primer  with  the  terminal  wires  of 
the  battery.  When  thus  connected,  the  battery  current  heats 
the  platinum  sufficiently  to  ignite  a  small  piece  of  loose  gun- 
cotton,  which,  together  with  the  platinum  wire,  occupies  the 
slotted  portion  of  the  wooden  cylinder.  The  ignited  gun-cotton 
communicates  flame  to  the  powder  in  the  long  tube. 

202.  Sabots  are  circular  blocks  of  wood,  fastened  with  tin 
straps  to  hollow  projectiles  for  smooth-bore  guns.  Their  object 
is  to  prevent  the  projectile  from  turning  in  the  bore  and  bring- 
ing the  fuse  in  contact  with  the  charge  of  the  piece.  The  diam- 
eter of  the  sabot  corresponds  to  that  of  the  projectile ;  it  has  a 
shallow  dish-shaped  cavity  for  the  projectile  to  rest  in,  and  is 
always  attached  to  the  side  opposite  the  fuse-hole. 

When  the  piece  is  fired,  the  fragments  of  the  sabot  fly  a  short 
distance  from  the  muzzle;  consequently  it  is  dangerous  to  use 
this  kind  of  ammunition  when  firing  over  the  heads  of  our  own 
troops.  Owing  to  the  liability  of  premature  explosions,  the  same 
objection  applies  to  hollow  projectiles  of  every  variety. 

The  metallic  ring,  or  cup,  attached  to  the  base  of  rifled  project- 
iles for  the  purpose  of  expanding  into  the  grooves  of  the  piece 
and  giving  rotary  motion  to  the  projectile,  is  also  called  a  sabot. 


IMPLEMENTS.  53 


IMPLEMENTS. 

203*  Implements  for  artillery  are  those  instruments  employed 
In  loading,  pointing,  and  firing  cannon,  and  in  mechanical  ma- 
noeuvres therewith. 

Equipments  are  those  things  used  for  the  same  object,  but 
which  are  carried  by  the  individual  men. 

204.  thinner's  quadrant  (Fig.  10,  Plate  IV)  is  an  instrument 
for  giving  elevation  or  depression  to  a  piece.  It  consists  of  a 
graduated  quarter  of  a  circle  of  sheet  brass,  of  six  inches  radius, 
attached  to  a  straight  brass  bar  twenty-two  inches  long.  It  has 
an  anil  carrying  a  spirit-level  at  its  middle,  and  a  vernier  and 
clamp  screw  at  its  movable  end.  The  arc  is  graduated  to  half 
degrees,  and  the  vernier  reads  to  five  minutes.  To  get  a  required 
elevation,  the  vernier  is  set  at  the  indicated  degree ;  the  brass  bar 
is  next  inserted  in  the  bore  parallel  to  the  axis;  the  piece  is  then 
elevated  or  depressed  until  the  level  is  horizontal.  The  elevation 
may  likewise  be  obtained  by  applying  the  bar  to  the  face  of  the 
piece,  care  being  taken  to  have  it  in  a  plane  parallel  to  ttie  plane 
of  fire.     The  latter  is  the  mode  of  using  it  with  mortars. 

The  difficulty  of  applying  the  quadrant  to  the  muzzle  of  guns, 
especially  to  those  in  embrasure,  has  suggested  that  a  metallic 
ledge  be  attached  to  the  end  of  a  trunnion ;  upon  this  ledge  the 
bar  of  the  quadrant  is  applied  when  the  elevation  is  to  be  given. 
The  top  of  the  ledge  is  parallel  with  the  axis  of  the  bore. 

205.  Gunner's  level  is  an  instrument  for  marking  the  line  of 
metal  on  a  piece.  Until  within  a  very  recent  period  it  was  re- 
quired with  all  pieces,  but  since  the  application  of  sights  to  guns 
its  use  is  confined  solely  to  mortars ;  and  owing  to  the  fact  that 
these  pieces  are  left  rough  and  unturned  on  the  exterior,  the  line 
of  metal  marked,  in  the  usual  manner,  with  the  gunner's  level 
and  a  chalk-line,  is,  at  best,  but  a  crude  and  imperfect  method  of 
obtaining  a  line  of  sight.    (Fig.  11,  Plate  IV.) 

The  method  of  using  this  instrument  is  readily  understood  by 
an  inspection  of  it. 

Sponge.    This  is  a  woolen  brush,  attached  to  a  staff,  used  in 

cleaning  the  bore  of  cannon,  and  for  extinguishing  any  burning 

fragments  of  cartridge  that  may  remain  after  firing.    For  field 

"ieces  the  sponge  and  rammer-heads  are  on  the  opposite  ends  of 

le  same  staff;  for  siege  and  sea-coast  pieces  they  are  attached 

>  separate  staves. 

With  pieces  of  less  than  eight  inches  calibre  the  sponge-head 
nsists  of  a  cylindrical  block  of  wood  about  three  calibres  in 
lgth ;  upon  this  is  tacked  the  woolen  stuff  forming  the  sponge, 
^r  pieces  of  larger  calibre  a  spring-head  (Fig.  4,  Plate  V)  is 
ed.   This  consists  of  three  pieces  of  sheet  iron,  so  fashioned  as 


54  IMPLEMENTS. 

to  form,  when  put  together,  a  serai-ellipsoid  corresponding  to  the 
bottom  of  the  bore  of  the  piece  for  which  intended.  To  these 
plates  is  attached  the  sponge  material,  which  is  secured  by  pack- 
thread stitching  through  holes  in  the  iron.  Each  plate  is  at- 
tached to  the  staff  by  a  steel  strap ;  these  by  their  spring  allow 
the  plates  to  close  together  and  enter  the  bore  with  a  tight  fit. 
The  necessary  size  is  thus  secured  without  the  greater  weight  of 
solid  wooden  heads. 

Sponges  are  protected  from  the  weather  by  canvas  covers, 
which  are  painted.  They  are  preserved  from  moths  by  the  same 
means  used  for  cartridge-bags.    (Par.  568.) 

The  rammer.  This  is  used  for  shoving  the  cartridge  and  pro- 
jectile to  their  place  in  the  bore  of  the  piece.  For  small  calibres 
the  head  of  the  rammer  is  a  short  cylindrical  piece  of  tough  wood, 
fixed  to  the  end  of  a  staff;  for  the  larger  calibres  it  consists  of  a 
wooden  ring  bound  with  iron  or  copper  and  attached  to  the  staff 
by  three  iron  prongs  or  straps.  (Fig.  5,  Plate  V.)  This  secures 
lightness  with  the  necessary  size. 

The  ladle  is  a  copper  scoop  (Fig.  6,  Plate  V)  attached  to  a 
staff.  It  is  used  for  scooping  out  the  powder  of  a  cartridge 
which  may  have  become  broken  when  withdrawing  it  from  the 
bore. 

The  worm  (Fig.  7,  Plate  V)  is  a  species  of  double  cork-screw 
attached  to  a  staff,  and  is  used  for  withdrawing  cartridges  from 
pieces. 

The  pass-box  is  a  wooden  or  metallic  box  with  a  lid  and  han- 
dles, used  for  carrying  cartridges  from  the  service  magazine  to 
the  piece.  The  boxes  are  of  various  sizes  to  suit  the  calibre  of 
the  piece,  one  cartridge  being  carried  at  a  time. 

The  budge-barrel  is  a  barrel,  to  the  top  of  which  is  attached 
a  leather  cover,  which  is  gathered  with  a  draw-string  like  the 
month  of  a  satchel.  It  is  used  with  pieces  requiring  small-sized 
cartridges,  to  carry  the  in  from  the  magazine  to  near  the  pieces 
to  be  served. 

The  priming-wire  is  used  to  clear  the  vent  and  prick  a  hole  in 
the  cartridge.  This  latter  is  not,  however,  an  absolute  essential, 
as  the  explosion  of  the  primer,  as  now  made,  will,  with  ordinary 
cartridges,  cany  flame  to  the  powder. 

The  vent-gimlet  is  a  long  gimlet  for  removing  obstructions 
from  the  vent. 

The  vent-punch  is  an  instrument  for  the  same  purpose.  As 
these  instruments  are  made  of  hardened  steel,  great  care  must 
be  observed  in  using  them,  that  they  do  not  break  in  the  vent 
and  spike  the  piece. 

The  fuse-setter  is  a  brass  drift  for  driving  wooden  fuse-plugs 
into  shells. 


IMPLEMENTS.  00 

Fuse-wrench  is  a  three-pronged  wrench  used  for  selling  lust- 
plugs  that  are  to  be  screwed  into  the  shell.  One  prong  con- 
tains forks  for  the  fuse-plug,  and  another  one  smaller  fork*  for 
the  water-cap. 

Fvse-block,  sometimes  called  fuse-gauge,  (Fig.  8,  Plate  F,)  is 
a  simple  contrivance  for  holding  paper  time-fuses  when  being 
cut.  It  consists  of  two  blocks  of  wood  hinged  together  so  as  to 
open  and  shut  after  the;  manner  of  a  book.  In  each  end  is  a 
recess  into  which  the  fuse  is  placed,  and  where  it.  is  securely 
held  by  pressing  the  blocks  tightly  together.  The  fuse  is  put  in 
with  the  small  end  extending  out  of  the  end  of  the  block,  the 
point  at  which  it  is  to  be  cut  being  even  with  the  end  of  the 
block. 

Along  one  side  of  the  recess  is  attached  a  brass  scale.  This 
was  intended  for  fuses  of  obsolete  pattern.  As  now  made,  each 
fuse  is  divided  into  as  many  equal  parts  as  the  number  of  sec- 
onds for  which  its  entire  length  (two  inches)  is  intended  to  burn. 
These  parts  are  marked,  and  are  the  guides  in  cutting  the  fuse; 
the  latter  operation  being  performed  with  the  fuse-knife*  which 
is  a  sharp  thiu-bladed  knife,  (preferably  a  shoe-knife,)  or  a 
line  saw.     ( See  Fuses,  par.  196.) 

Fuse-plug  extractor.  This  is  an  instrument  for  extracting 
fuse-plugs  after  they  have  been  driven.  It  is  a  stout  screw, 
which  may  be  screwed  into  the  fuse-hole  of  the  plug,  which  is 
then  pulled  out  by  means  of  a  screw  operating  after  the  manner 
of  certain  kinds  of  cork-screws. 

Fuse-reamer  is  used  to  enlarge  the  hole  in  a  fuse-plug  so  as  to 
make  it  of  proper  size  for  the  paper  fuse. 

Powder-measures  are  made  of  copper,  of  cylindrical  form  and 
of  various  sizes,  for  the  purpose  of  determining  the  charges  for 
shells  and  cannon  by  measurement.  ICach  measure  is  marked 
with  the  weight  of  mortar  powder  which  it  holds.  They  come 
in  sets,  holding  from  one  ounce  up  to  several  pounds,  and  fit. 
together  in  a  nest. 

Lanyard  is  a  strong  cord,  one  end  of  which  has  a  small  iron 
hook  and  the  other  a  wooden  handle.  It  is  used  for  exploding 
the  friction-primer  when  a  piece  is  to  be  fired. 

Shell-hooks  is  an  implement  constructed  to  fasten  into  the 
ears  of  a  shell  for  the  purpose  of  lifting  it  to  the  muzzle  of  the 
piece. 

Gunnels  pouch  and  pHmer-pouch  are  made  of  leather,  and  are 
attached  to  the  person  by  a  strap  buckling  around  the  waist. 
Cartridge-pouch  is  made  of  leather,  and  is  carried  suspended 

rom  the  shoulder  to  the  opposite  side.    It  is  used  when  small 

artrklges  are  required,  for  carrying  them  from  the  magazine  or 

>nd£e-barrel  to  the  piece. 


66  MOTION   OF   PROJECTILES. 

Sight-pouch  is  a  long,  slender  case,  used  sometimes  for  carry- 
ing the  breech  sight.    It  is  suspended  from  the  shoulder. 

Handspikes.  With  siege  guns  and  mortars,  wooden  band- 
spikes  are  used  for  manoeuvering  them.  Those  for  mortars  are 
shod  with  iron,  which  is  turned  up  in  a  way  to  prevent  slipping 
on  the  platform. 

Guns  with  iron  carriages  have  iron  handspikes,  made  to  fit 
into  the  mortises  of  the  truck-wheels. 

Elevating-bar  is  a  stout  bar  of  iron  with  one  end  squared  and 
made  to  fit  into  the  ratchets  on  the  breech  of  the  piece  for  the 
purpose  of  giving  elevation.  It  is  operated  as  a  lever,  the  fulcrum 
being  the  ratchet-posts  of  the  carriage. 

The  implements  and  machines  used  for  mechanical  manoew- 
vres,  for  the  inspection,  and  for  the  aiming  of  cannon,  are  de- 
scribed under  those  heads  respectively. ' 


MOTION    OF    PROJECTILES    AND    DEVIATING 

CAUSES. 

206.  A  projectile  fired  from  a  cannon  is  acted  on  by  four 
distinct  forces,  viz.:  First,  the  projectile  force  ;  second,  the  force 
of  gravity;  third,  the  resistance  of  tiie  air;  fourth,  the  friction 
against  the  surface  of  the  bore. 

With  the  exception  of  gravity,  none  of  these  forces  are  con- 
stant, varying  not  only  for  different  pieces,  but  for  different  shots 
from  the  same  piece. 

The  projectile  force  is  that  produced  by  the  combustion  of  the 
powder  in  the  piece,  causing  sudden  development  of  gas,  tiie 
expanding-  force  of  which,  acting  on  the  projectile,  impels  it 
forward  and  out  of  the  piece.  It  is  physically  impossible  to  ob- 
tain exact  uniformity  in  the  charges.  In  practice  there  will 
always  be  a  difference  in  weight  and  shape  in  the  cartridges, 
and  in  pushing  them  home,  greater  pressure  will  be  applied  at 
one  time  than  at  another,  thus  causing  want  of  uniformity  in 
combustion.  The  temperature  of  the  piece,  arising  from  pre- 
vious discharges  and  from  the  temperature  of  the  air  or  ra£s  of 
the  sun ;  the  nature  of  the  projectile  and  its  movement  in  the 
bore;  the  condition  of  the  bore  with  respect  to  humidity  and 
foulness, — all  have  more  or  less  influence  on  the  combustion  of 
the  powder,  and  consequently  on  the  velocity  and  range.  Above 
all,  however,  is  the  want  of  uniformity  in  the  quality  of  powder. 
In  this  respect  considerable  latitude  must  be  allowed  in  the  size 
and  density  of  grain  or  pallet,  in  the  manipulation  of  the  ingre- 
dients, and  in  its  condition  resulting  from  age,  moisture,  and 
handling.     With  small  charges,   especially  with  fine-grained 


MOTION   OF  PROJECTILES. 


57 


powder,  it  is  possible  to  so  mix  the  contents  of  different  barrels 
for  any  series  of  shots  as  to  secure  a  fair  degree  of  uniformity  for 
that  particular  occasion ;  but  with  charges  requiring  large  quanti- 
ties of  powder,  this,  except  to  a  limited  degree,  is  impracticable. 

The  force  of  gravity.  Am  soon  as  the  projectile  leaves  the  muz- 
zle of  the  piece  this  force  has  free  power  to  act,  and  draws  the 
projectile  downwards,  causing  it  to  describe  a  curve. 

The  resistance  of  the  air.  The  projectile,  in  passing  through  the 
air,  meets  from  it  a  resistance  depending  in  intensity  upon  tiie 
velocity,  the  shape  of  the  projectile,  and  density  of  the  air.  This 
resistance  consumes  a  portion  of  the  projectile  force,  which,  being 
gradually  diminished,  causes  the  projectile  to  pass  over  unequal 
spaces  in  equal  intervals  of  time.  These  spaces  gradually  diminish- 
ing, give  to  the  trajectory  unequal  curvatures  in  its  two  branches, 
that  of  the  last  part  being  much  more  curved  than  the  first. 

Atmospheric  resistance  increases  as  the  square  of  the  velocity, 
and  with  the  cross-section  of  the  projectile  exposed  to  the  action 
of  the  resistance.  ' 

It  is  manifest  that  the  resistance  due  to  the  atmosphere  varies 
with  the  density  of  the  latter,  and  this  depends  upon  aud  varies 
with  the  temperature,  the  humidhy,  and  the  barometric  press- 
ure.   The  retarding  effect  of  rain  is  evident. 

The  foregoing  influences  operate  principally  in  a  vertical  di- 
rection, and  therefore  affect  only  the  range.  Other  influences 
affect  lateral  accuracy,  among  which  may  be  mentioned  wind^ 
the  velocity  and  force  of  which  are  classified  as  follows : 


1 

Velocity. 

Pressure  on 

1  square 

foot. 

Common  designations  of  the  force 
of  the  wind. 

In  1  hour. 

In  1  see'd. 

Miles. 

1 

2 

3 

4 

5 

10 

15 

20 

25 

30 

35 

40 

45 

50 

60 

80 

100 

Feet. 

1.47 

2.93 

4.40 

5.87 

7.33 

14.67 

22.00 

29.34 

36.67 

44.01 

51.34 

58.68 

66.01 

73.35 

88.02 

117.36 

146.70 

Lbs. 
0.005 
.020? 

.044  5 
.079? 

.123  5 

.492? 

1.107  5 

1.9G8  ? 

3.075  5 
4.429  ? 
6.027  5 
7.873? 

9.963  5 
12.800 
17.715 
31.490 
49.200 

Hardly  perceptible. 
Just  perceptible. 

Gentle,  pleasant  wind. 

Pleasant,  brisk  breeze. 

Very  brisk. 

High  wind. 

Very  high. 

A  storm  or  tempest. 
A  great  storm. 
A  hurricane. 

A  hurricane  that  tears  up  trees, 
carries  buildings  beforo  ft,  4c. 

58  MOTION   OF   PROJECTILES. 

» 

It  is  evident  from  the  foregoing  that  the  effect  of  wind,  on  so 
large  a  body  as  a  cannon  projectile,  is  considerable.  This  effect 
is  in  direct  proportion  to  the  strength  of  the  wind  and  the  time 
of  flight  of  tiie  projectile. 

When  the  wind  crosses  the  plane  of  fire,  the  deviation  of 
spherical  projectiles  is  on  the  side  towards  which  the  wind  is 
moving;  with  elongated  projectiles,  especially  shells  and  cored 
shot,  the  wind  has  a  slight  tendency  to  cause  them  to  go  in  the 
opposite  direction.  Wind  coming  from  the  left  tends,  therefore, 
to  correct  the  drift  of  rifle  projectiles,  the  latter  being  always 
to  the  right;  when  coming  from  the  right  it  augments  the  drift. 
A  front  wind  diminishes  the  range;  when  coming  from  the  rear 
it  increases,  but  to  a  very  slight  degree,  the  range. 

When  the  range  is  great  the  projectile  may  have  to  traverse 
several  currents  of  air  of  different  directions  and  velocities.  This 
would  have  the  effect  of  giving  a  waving  motion  to  the  pro- 
jectile. 

The  condition  of  the  atmosphere  with  reference  to  mirage  has 
a  marked  influence  upon  accuracy  of  aiming;  for  it  is  evident 
that  a  projectile  will  not  strike  the  object  if  the  piece  is  directed 
only  at  the  reflected  image  of  it. 

Aberrations  arising  from  atmospheric  influences  are  so  nu- 
merous and  subtle  as  to  make  it  impracticable  to  formulate  them 
into  tables  useful  for  practical  gunnery.  Practice  at  small-arm 
tiring,  as  now  con  dueled  at  rifle-ranges,  leads  to  habits  of  obser- 
vation and  exercise  of  sound  judgment  highly  advantageous  to 
the  artillerist. 

Friction  against  the  bore.  The  projectile,  in  passing  along  the 
bore,  experiences  more  or  loss  friction ;  this  lias  a  retarding 
effect,  varying  the  veloeitj'  and  consequently  the  range.  The 
unequal  degree  of  friction  at  different,  parts  of  the  bore  may 
cause  the  projectile  to  leave  the  muzzle  with  a  greater  pressure 
on  one  side  than  on  the  other,  forcing  it  to  deviate  from  the 
true  line  of  fire.  This  is  more  particularly  the  case  with  spher- 
ical projectiles,  in  which  there  is  considerable  windage  and  bal- 
loting, than  with  rifle  projectiles. 

Resistance  from  rifling.  The  cup  or  sabot  of  an  elongated 
projectile,  expanding  from  the  pressure  of  the  gas,  fills  the 
grooves,  which,  heing  inclined  to  the  axis  of  the  bore,  offer 
resistance  to  the  forward  motion  of  the  projectile.  That  side  of 
each  groove  towards  the  muzzle  is  the  one  against  which  the 
expanded  sabot  constantly  impinges,  and  is  called  the  cl living' 
side. 

Owing  to  the  mechanical  impossibility  of  constructing  guns 
and  projectiles  of  exact  uniformity,  a  certain   departure  from 


AIMING.  50 

the  true  dimensions  is  allowed  in  receiving  them  from  tin* 
manufacturer.  This,  to  a  certain  degree,  prevents  uniformity 
in  firing.  Roughness  of  the  bore  and  projectile,  especially  with 
rifles,  influences  velocity,  accuracy,  and  range.  The  bore  be- 
comes foul  from  firing,  and  this  foulness  i*  hard  and  rough  or 
soft  and  mictions,  depending  on  the  humidity  of  the  atmosphere, 
or  whether  the  sponge  is  moist  or  dry.  With  rifle  projectiles, 
lubrication,  or  the  want  of  it,  lias  a  marked  effect  upon  their 
range  and  accuracy. 

Want  of  uniformity  in  the  density,  weight,  figure,  and  centre 
of  gravity  of  projectiles,  are  other  sources  of  error  in  firing. 

In  many  instances  these  various  sources  of  aberration  may 
combine  in  such  manner  as  to  partly  neutralize  each  other.  Ou 
the  other  hand,  they  may  so  fall  together  as  to  produce  the 
maximum  degree  of  inaccuracy. 

In  addition  to  the  foregoing,  there  are  other  sources  of  error 
in  firing,  which,  although  exceedingly  minute,  nevertheless  exist. 
Among  these  may  be  mentioned  the  influence  of  the  axial  rota- 
tion of  the  earth ;  the  spring  of  the  carriage ;  the  dip  of  the  muz- 
zle; the  effect  of  the  rays  of  the  sun  in  heating  one  side  of  the 
piece  more  than  the  opposite  side,  and  a  like  effect  on  the  pro- 
jectile. 

Prom  the  foregoing,  it  must  be  evident  that  exact  uniformity 
of  firing  with  any  piece  is  an  impossibility.  It  is  by  practice- 
alone  that  the  artillerist  can  be  brought  to  distinguish  between* 
inherent  defects  and  faults  of  gunnery  which  he  may  correct. 


Aiming. 

207.  To  aim  a  piece  of  artillery  is  to  give  it  such  a  direction 
and  elevation  as  will  cause  the  projectile  to  strike  the  object,, 
and  the  rule  is :  first  give  the  direction,  and  then  the  elevation- 
With  the  exception  of  mortars,  all  modern  pieces  are  furnished 
with  two  sights :  a  front  one  and  a  rear  one.  These  are  situated 
either  on  the  line  of  metal,  or  slightly  to  the  right  of  it  in  a  plane 
parallel  to  the  plane  of  lire. 

The  front  sight  i3  securely  attached  to  the  piece  by  means  of 

a  screw,  and  for  the  heavier  class  of  guns  is  over  the  axis  of  the 

Tuuuions. 

The  rear  sight  is  on  the  breech,  fitting  into  a  socket  attached 

o  the  piece  with  screws,  and  when  the  gun  is  to  be  discharged 

j  removed  from  the  socket. 

For  the  10  and  15  inch  guns  the  breech  sight  is  without  grad- 
ation, and  serves  merely  to  give  direction  to  the  piece,  the  ele- 


60  AIMING. 

vation  being  given  by  means  of  the  elevating-arc,  or,  when  prac- 
ticable, with  the  quadrant  applied  in  the  muzzle. 

208.  For  siege  and  Parrott  guns  the  breech  sights  are  grad- 
uated to  correspond  to  degrees  and  parts  of  degrees  of  elevation 
of  the  axis  of  the  bore,  and  have  a  slide  to  move  up  or  down. 
This  slide  has  a  screw  thread  cut  on  one  end  of  it,  upon  which 
works  a  nut  with  four  short  arms;  through  each  of  these  arms 
Is  a  small  hole  for  sighting.  The  screw  upon  the  slide  is  for 
the  purpose  of  giving  lateral  motion,  when  allowing  for  drift. 

Each  kind  of  gun  has  its  particular  breech  sight,  but,  as  there 
are  in  service  many  of  old  or  experimental  pattern,  they  should 
be  verified  for  the  particular  pieces  upon  which  they  are  to  be 
used.  This  is  done  by  directing  the  piece  at  some  wTell-defined 
point  at  a  distance  of  1000  yards  or  more,  and  on  the  same  hori- 
zontal plane  with  the  axis  of  the  trunnions.  A  straight-edge 
and  spirit-level  applied  to  the  face  of  a  trunnion  suffices  for  this 
•operation.  Place  the  slide  of  the  breech  sight  at  any  degree  of 
the  graduation,  and,  sighting  through  it  at  the  object,  give  the 
piece  the  corresponding  elevation.  Insert  the  gunner's  quad- 
rant into  the  bore,  and  ascertain  from  it  the  inclination  of  the 
axis  of  the  piece.  If  the  reading  on  the  breech  sight  corre- 
sponds to  that  of  the  quadrant,  the  former  is  correct.  The  line 
of  sight  passing  through  the  zero  of  the  breech  sight  is  parallel 
to  the  line  of  fire. 

209.  For  10  and  15  inch  guns  an  elevating-arc  is  used.  This 
consists  of  a  strip  of  brass  attached  to  the  base  of  the  breech 
parallel  to  the  ratchets.  It  is  graduated  into  degrees  and  parts 
of  degrees,  and  a  pointer,  attached  to  the  ratchet-post,  indicates 
the  elevation  or  depression  of  the  piece.  When  the  pointer  is  at 
zero,  the  axis  of  the  piece  is  horizontal.  Besides  the  graduation 
on  the  arc,  the  ranges  in  yards  for  the  ordinary  charges  for  shot 
and  shell  are  given. 

In  batteries  for  garrison  and  sea-coast  defense,  where  the 
platforms  are  fixed,  the  line  of  metal  may  be  considered  as  per- 
manent; but  with  siege  guns,  mounted  on  traveling  carriages, 
the  wheels  are  liable  to  vary  in  position  from  unevenness  of 
ground,  or  unequal  settling  in  newly -constructed  platforms. 
This  line  is  constantly  changing,  and  approximates  the  higher 
wheel  in  proportion  to  the  difference  of  level  between  the  wheels ; 
hence,  to  secure  accuracy  of  fire,  allowance  must  be  made  by 
observing  where  the  .shots  strike  and  correcting  the  aim  accord- 
ingly. Deviation  from  this  cause  is  always  towards  the  side  of 
the  lowest  wheel. 

210.  All  range  tables  are  made  out  with  reference  to  the 
horizontal  plane  passing  through  the  axis  of  the  trunnions; 


AIMING. 


61 


when  the  object  to  be  fired  at  is  situated  oil  a  plane  lower  than 
this,  an  allowance  must  be  made  for  this  difference  of  level  by 
deducting  from  the  elevation  laid  down  in  the  table  of  ranges. 

The  following  table  is  calculated  for  cases  in  which  the  piece 
is  above  the  object;  it  will  also  serve  with  sufficient  degree  of 
approximation  for  cases  in  which  the  piece  is  below  the  object,, 
by  simply  reversing  the  method  of  application ;  i.  «.,  by  adding,, 
instead  of  subtracting,  the  quantity  clue  to  the  height  and  dis- 
tance. 


H 
O 

H 

00 


Yards. 

1000 
1100 
1200 
1300 
1400 
1500 
1600 
1700 
1800 
1900 
2000 
2100 
2200 
2300 
2400 
2500 
3000 
3500 
4000 
4500 
5000 


HEIGHT. 


lFt.      2  Ft. 


1.1 

1. 
.9 
.9 
.8 
.8 
.7 
.7 
.6 
.6 
.6 
.5 
.5 
.5 
.5 
.4 
.4 
.3 
.3 
.3 
.2 


2.3 

2.1 

1.9 

1.8 

1.6 

1.5 

1.4 

1.3 

1.3 

1.2 

1.2 

1.1 

1. 

1. 

1. 

.9 

.8 

.7 

.6 

.5 

.5 


4  Ft. 

8  Ft. 

16  Ft. 

o      t 

o      / 

o      / 

4.6 

9.2 

18.3 

4.2 

8.S 

16.7 

3.8 

7.6 

15.3 

3.5 

7. 

14.1 

8.3 

6.5 

13.1 

3. 

6.1 

12.2 

2.9 

5.7 

11.4 

2.7 

5.4 

10.8 

2.5 

5.1 

10.2 

2.4 

4.8 

9.6 

2.3 

4.6 

9.2 

2.2 

4.3 

8.7 

2.1 

4.2 

8.4 

2. 

4. 

7.9 

1.9 

3.8 

7.6 

1.8 

3.6 

7.3 

1.5 

3. 

6.1 

1.3 

2.6 

5.2 

1.1 

2.3 

4.6 

1. 

2. 

4.1 

.9 

1.8 

3.7 

32  Ft.     64  Ft. 


36.7 
33.8 
30.6 
28.2 
26.2 
24.4 
22.9 
21.6 
20.4 
19.3 
18.3 
17.5 
16.7 
15.9 
15.3 
14.7 
12.2 
10.4 
9.2 
8.1 
7.3 


13.3 
6.7 
1.1 
56.4 
52.4 
48.9 
45.8 
43.1 
40.7 
38.6 
36.7 
34.9 
33.3 
31.9 
30.6 
29.3 
24.4 
21. 
18.3 
16.3 
14.7 


96  Ft. 


80. 
40. 
31.7 
24.6 
18.6 
13.8 
8.7 
4.7 
1.1 
57.9 
55. 
52.4 
50. 
47.8 
45.8 
44. 
36.7 
31.4 
27.5 
24.4 
22. 


When  the  height  of  the  piece  above  the  water  or  horizontal 
plane  is  known,  the  angle  of  depression  for  different  distances- 
can  be  found  thus :  Find  the  angle  for  any  height  not  given  in 
the  table,  as  follows  :  divide  the  given  height  into  parts,  which 
are  found  in  the  table,  using  the  largest  numbers  possible ;  and 
dd  the  angles  corresponding  to  those  parts,  for  the  required 
listance.    Example :  Required  the  angle  for  distance  1000  yards 
<nd  height  130  feet.     130  feet  gives  the  parts  96%  32',  and  2'; 
he  sum  of  the  angles  for  these  lieights  is  1°  50'+  36.7'+ 2.3'= 
3 29';  the  amount  to  be  deducted  from  the  elevation  as  given 
i  the  table  of  ranges  for  the  particular  piece  used. 


62  AIMING. 

211.  Owing  to  the  great  range  at  which  rifled  guns  are  used, 
and  of  the  accuracy  of  fire  demanded  of  them,  it  is  important 
that  they  should  be  provided  with  aiming  apparatus  more  per- 
fect th  in  the  coarse  and  clumsy  sights  heretofore  supposed  to 
1x3  sufficient  for  artillery  purposes. 

The  Lorain  sight,  (Plate  VL)  of  which  the  following  is  a  brief 
description,  combines  the  properties  most  desirable  in  a  sight 
for  heavy  rifled  guns. 

This  instrument  is  essentially  a  transit  with  a  vertical  and 
horizontal  limb,  the  former  to  give  the  required  elevation  or 
■depression,  and  the  latter  to  give  proper  allowance  for  drift. 

The  telescope  (A)  has  a  top,  a  front  and  rear  open  sight  (a  a'), 
used  to  bring  the  object  aimed  at  within  the  field  of  view. 

The  vertical  limb  (B)  is  graduated  to  degrees.  The  least  count 
of  the  vernier  (b)  is  six  minutes. 

The  tangent  screw  (C)  elevates  or  depresses  the  telescope. 

The  horizontal  limb  (D)  has  a  scale  of  20°  ou  each  side  of  the 
aero,  which  is  graduated  to  degrees. 

The  standards  (E  E')  are  supported  by  the'horizontal  limb. 

The  tangent  screw  (F)  moves  the  horizontal  limb  to  right  or 
left. 

The  base  of  the  instrument  (G)  has  on  it  the  vernier  (g)  of  hori- 
zontal limb,  the  least  count  of  which  is  six  minutes. 

When  in  use,  this  instrument  sits  in  a  seat(H)  which  is  screwed 
on  to  the  right  trunnion  of  the  gun. 

This  sent  is  so  placed  that  the  plane  of  its  top  is  parallel  to  the 
horizontal  plane  through  the  axis  of  the  bore.  When  the  verti- 
•cal  limb  is  at  zero,  the  axis  of  the  telescope  will  be  parallel  to 
the  axis  of  the  bore,  if  the  zero  of  the  horizontal  limb  coincides 
with  the  mark  (I)  on  the  seat. 

This  mark  (I)  i*  on  a  movable  piece  (K)  attached  to  seat,  and 
Its  position  is  easity  determined. 

The  elevations  given  witli  this  sight  and  with  a  quadrant  do 
not  agree,  the  latter  being  measured  from  the  horizontal  and 
the  former  from  the  line  from  sight  to  object.  In  firing  froru 
above  an  object,  the  telescopic  sight  requires  more  elevation 
than  the  quadraut.  If  from  below  an  object,  it  requires  less 
elevation  than  the  quadrant. 

When  the  piece  is  to  be  fired,  the  instrument  is  lifted  out  of 
its  .'•cat.  One  instrument  suffices  for  three  or  four  guns,  it  being 
carried  from  piece  to  piece  as  they  are  prepared  for  firing.  For 
short  range  and  rapid  firing,  the  pieces  should,  in  addition,  have 
the  ordinary  sighting  arrangements. 

Note. — The  proper  place  for  the  sight  is  on  the  left  trunnion  ; 
but  as,  with  carriages  now  constructed,  it  would  be  interfered 
with  by  the  crane,  it  is  placed  on  the  right  trunnion. 


AIMING  MORTARS.  63 


Aiming  mortars.  v 

212.  Mortars,  like  other  cannoa,  are  aimed  by  first  giving 

the  direction  and  then  the  elevation. 

The  elevation,  which  is  usually  that  of  tiie  greatest  range  of 
projectiles  in  vacuo,  viz.,  45°,  is  determined  by  applying  the 
quadrant  to  the  face  of  the  piece,  and  raising  or  lowering  the 
breech  until  that  number  of  degrees  is  indicated. 

The  charge  of  powder  is  varied  to  suit  the  required  range. 

To  give  the  shell,  for  the  same  range,  a  greater  velocity  in  the 
descending  branch  of  its  trajectory,  the  mortar  is  sometimes 
fired  at  an  angle  of  60°,  in  which  case  the  charge  of  powder  must 
be  increased  accordingly. 

As  mortars  are  usually  masked  from  the  object  to  be  bom- 
barded by  an  epaulment  or  parapet,  different  means  from  those 
used  with  guns  become  necessary  forgiving  them  their  direction. 

There  are  several  processes  employed,  all  of  which,  however, 
are  reduced  to  determining  practically  two  fixed  points  which 
shall  be  in  line  with  the  piece  and  the  object,  and  sufficiently 
near  to  be  readily  distinguished  by  the  person  pointing  the 
mortar.  These  points  determine  a  vertical  plane  which,  when 
including  the  line  of  metal,  becomes  the  plane  of  fire. 

The  various  methods  are  explained  in  pars.  342  and  343. 

213*  The  following  is  a  description  of  Dyer's  pointing  appa- 
ratus, and  instructions  for  its  use. 

This  method  is  easy  of  application,  and  is  especially  adapted 
for  use  with  mortars  mounted  on  centre-pintle  carriages;  it  is 
also  readily  adapted  for  use  with  mortars  mounted  on  ordinary 
and  temporary  platforms.  Practically  it  is  independent  of  the 
distance  from  the  crest  of  the  parapet  to  the  platform.  The 
method  is  as  follows : 

Find  the  point  where  the  vertical  plane  containing  the  directrix 
of  the  platform  cuts  the  interior  crest  of  the  parapet.  At  this 
point  establish  a  level  plate  containing  an  arc  graduated  both 
ways  from  the  point  where  the  vertical  plane  cuts  it,  the  centre 
being  the  point  first  established  on  the  interior  crest.  An  arm 
with  two  vertical  sights  revolves  about  this  point  as  a  centre, 
and  determines,  by  means  of  an  indicator  attached  to  the  front  of 
fhe  arm,  the  angle  made  by  any  object  with  the  vertical  plane 

hrongh  the  centre,  called  the  plane  of  the  zeros.    The  mortar 

einjr  given  the  same  angle  with  the  plane  of  the  zeros,  the  plane 

f  fire  will  practically  intersect  the  object. 

To  apply  this  method  to  a  mortar  mounted  on  a  centre-pintle 

trriage :  On  the  rear  of  the  platform,  with  the  centre  of  the 
title  as  a  centre,  describe  an  arc.    Find  the  point  where  the 


64  RICOCHET   FIRING. 

plane  of  the  zeros  cuts  this  arc,  and  mark  the  point  zero.  Divide 
the  arc  both  ways  from  the  point  into  degrees  and  parts  of  de- 
grees. An  indicator  attached  to  the  centre  of  the  rear  transom 
(in  the  vertical  plane  containing  the  axis  of  the  piece)  will  always 
mark  the  degrees  to  the  right  or  left  of  the  plane  of  the  zeros. 

( Plate  VII.) 

Description  of  the  pointing  instrument. 

A  horizontal  iron  plate  is  permanently  established  on  the  par- 
apet, the  rear  edge  being  on  the  crest  and  the  centre  in  the 
plane  of  the  zeros. 

In  order  that  the  same  instrument  may  be  used  at  different 
places  in  a  work,  or  be  removed  when  not  in  use,  a  detachable 
plate  containing  the  graduation  and  sights  is  adjusted  to  the 
permanent  plate,  as  shown  in  Fig.  1.  P  is  a  pintle  on  the  de- 
tached plate  which  fits  into  a  socket  in  the  permanent  one.  L  L. 
are  levels  on  the  detached  plate  J  inch  below  the  upper  surface 
of  the  plate.  S  S  are  leveling  screws.  By  the  use  of  this  plate 
the  index  arm  will  always  be  made  to  move  in  a  horizontal  plane. 

Application  of  the  method, 

1st.  Place  the  plate  containing  the  graduated  arc  on  its  bed, 
and  level  it  by  means  of  the  tangent  screws;  then  place  the  arm, 
to  which  the  sights  are  attached,  on  the  plate.  Traverse  the 
chassis  until  the  index  on  the  rear  transom  indicates  the  required 
number  of  degrees  as  indicated  by  the  instrument. 

If  the  arm  of  the  instrument  be  to  the  right  of  the  zero,  traverse 
the  chassis  to  the  left;  and  vice  versa. 

For  the  successful  operation  of  this  method  with  the  centre- 
pintle  mortar  carriage,  it  is  essential  that  the  guides  of  the  top- 
carriage  should  fit  true  and  snug  to  the  chassis  rails. 

Ricochet  Firing. 

214.  The  angle  of  fall  of  projectiles  in  vacuo  is  equal  to  the 
angle  of  elevation;  but  in  air  the  angle  of  fall  is  somewhat 
greater. 

It  is  known  from  experience  that  a  projectile  falling  upon 
ground  of  ordinary  firmness,  at  an  angle  not  greater  than  ten 
degrees,  or  upon  water  at  four  or  five  degrees,  will  generally 
make  one  or  more  bounds.  In  this  case  the  projectile  is  said  to 
ricochet. 

The  purpose  to  be  sought  in  ricochet  firing  is  to  cause  the 
projectile  to  bound  along  near  the  surface  of  the  ground  or  water, 


CARRIAGES.  65 

and  thus  increase  the  chances  of  hitting  the  object  to  be  destroyed. 
It  is  chiefly  advantageous  against  troops  in  the  Held,  and  against 
boats  and  unarmored  vessels.  With  the  exception,  however,  of 
occasional  use  against  the  latter  objects,  it  is  generally  but  inci- 
dental to  direct  firing.  Owing  to  the  inequalities  of  ground,  it  is 
uncertain  of  effect  when  employed  against  objects  on  lai»d. 

Spherical  projectiles  are  more  certain  of  ricochet  than  those  of 
elongated  form ;  with  the  latter  the  first  graze  usually  causes 
them  to  tumble^  after  which  their  motion  is  both  feeble  aud 
erratic. 

The  pieces  principally  employed  for  ricochet  firing  are  the 
8-rinch  howitzer  and  the  8  and  10  inch  siege  mortars.  The  first 
two  may  be  used  when  the  angle  of  fall  is  less  than  ten  degrees, 
and  the  latter  when  the  angle  of  fall  is  less  than  fifteen  degrees. 
With  the  howitzer,  a  range  of  2000  yards  ma}'  be  obtained;  with 
the  mortars,  the  limit  of  ricochet  is  about  1000  yards. 

With  the  15-inch  gun,  the  most  effective  ricochet  upon  smooth 
water  is  obtained  from  two  degrees  elevation;  this,  with  the 
piece  fifteen  feet  .above  the  water,  will  cause  the  first  graze  to 
take  place  at  a  distance  of  about  1500  yards,  giving  a  rebound 
of  about  800  yards  in  length  and  100  feet  in  height.  The  next 
rebound  will  be  about  500  yards  in  length,  after  which  they  rap- 
idly diminish  until  towards  the  last,  when  the  projectile  appears 
to  almost  roll  upon  the  surface  of  the  water.  The  extreme  range 
at  this  elevation  is  about  4000  yards,  and  the  number  of  distinct 
ricochets  about  thirty-five. 

The  slightest  roughness  of  the  water  has  a  decided  effect  upon 
ricochet,  diminishing  both  accuracy  and  range. 

With  elongated  projectiles,  after  the  first  strike,  the  course  is 
quite  erratic,  and  they  are,  therefore,  entirely  unsuited  for  accu- 
rate ricochet  firms. 


CARRIAGES. 

215.  Carriages  for  artillery  are  classified  as  traveling  and 
stationary.  The  former  are  for  artillery  that  is  to  be  moved  from 
place  to  place;  the  latter,  for  that  occupying  fixed  positions. 

Strength,  durability,  and  facility  in  serving  the  pieces  are  the 
ihief  requisites  for  all  carriages. 

Stationary  carriages  consist  of  two  parts :  the  carriage — or,  as 
t  is  usually  called,  the  top-carriage — and  the  chassis,  and,  with 

ie  exception  of  that  for  the  flank-casemate  howitzer,  an*,  all 

instructed  of  wrought-iron. 

216.  The  top-carriage  {Fig.  1,  Plate  VIII)  is  composed  of  two 

5 


66  CARRIAGES. 

cheeks,  held  together  by  two  plates  of  boiler  iron,  called  the 
front  and  rear  transoms.  Each  check  is  formed  of  two  plates 
of  boiler  iron  cut  to  a  triangular  shape,  separated  by  interposing 
at  the  edges  the  vertical  portion  of  a  T-shaped  bar.  The  hor- 
izontal branches  project  over  each  side  to  form  a  double  flange, 
giving  stiffness  to  the  cheeks.  Flat  bars  of  iron  are  placed 
between  the  plates  at  suitable  intervals  to  stiffen  the  cheeks  in 
the  direction  in  which  the  weight  and  recoil  of  the  piece  bear 
upon  them.    All  these  "parts  are  held  together  by  screw  bolts. 

The  piece  rests  between  the  cheeks,  and  is  supported  on  them 
by  the  trunnions,  which  work  in  circular  cavities  called  trunnion- 
beds.  This  permits  the  piece  to  have  free  play  for  purposes  of 
elevation  anil  depression. 

For  most  pieces,  the  motion  of  the  top-carriage  to  and  from 
battery  is  regulated  by  a  pair  of  truck-wheels,  one  on  each  side, 
which  work  on  an  eccentric  axle  placed  underneath  and  a  little 
in  front  of  the  axis  of  the  trunnions. 

The  wheels  are  thrown  into  gear  by  means  of  handspikes  in- 
serted into  sockets  upon  the  ends  of  the  eccentric  axle  ;  the 
wheels  then  rest  upon  the  top  of  the  chassis  rails,  and  only  the 
rear  part  of  the  soles  of  the  top-carriage  rest  on  the  chassis  rails 
and  have  sliding  friction.  The  wheels  are  thrown  out  of  gear  in 
the  same  manner ;  the  entire  soles  then  have  sliding  friction  upon 
the  chassis  rails,  thus  checking  recoil. 

In  the  15-inch  gun  carriage  there  are  two  pair3  of  truck-wheels, 
one  pair  being  placed  in  front,  as  just  described,  and  the  other 
pair  near  the  rear  end  of  the  carriage ;  the  rear  wheels  only  are 
on  eccentric  axles,  and  when  these  are  out  of  gear  the  soles  of 
the  top-carriage  rest  fairly  on  the  chassis  rails,  and  the  motion 
is  on  sliding  friction.  When  (he  rear  wheels  are  in  gear  the 
front  wheels  also  touch  the  chassis  rails,  and  the  top-carriage 
moves  on  rolling  friction.  To  prevent  the  rear  wheels  from 
working  out  of  gear  while  the  gun  is  being  run  from  battery,  or 
jumping  in  gear  when  the  piece  is  fired,  pawls  are  provided  for 
locking  the  rear  axle. 

When  the  rear  wheels  are  in  gear,  motion  is  communicated 
to  the  carriage  by  means  of  a  handspike  on  each  end  of  the 
front  axle.  This  handspike  carries  a  double  pawl,  which  works 
in  ratchets  or  cogs  on  the  truck- wheels.  The  handspike  is 
arranged  with  a  counterpoise,  consisting  of  a  heavy  piece  of 
iron  on  the  short  arm  of  the  lever. 

In  the  10  and  15  inch  guns,  as  also  in  mortars,  the  elevation 
and  depression  are  given  by  means  of  a  lever,  called  the  elevat- 
ing-bar. The  point  of  this  bar  works  in  ratchets  cut  in  the 
breech  of  the  piece.    The  fulcrum — usually  called  the  ratchet- 


CARRIAGES.  67 

post — rests  on  the  rear  transom  of  the  gun  carriage.  It  is  of 
cast-iron,  and  has  several  notches  for  adjusting  the  position  of 
the  elevating-bar. 

Carriages  for  the  8-inch  rifle  (converted)  have  an  improved 
elevating  apparatus.    This  is  described  in  par.  320. 

Guns  of  the  Parrott  pattern  have  an  elevating  screw.  This  is 
attached  to  the  rear  transom  of  the  carriage  at  its  lower  end, 
while  the  nut  is  connected  to  the  cascable  of  the  gun.  The 
screw  is  worked  by  a  handle  passing  through  it  above  the  nut. 
Both  screw  and  nut  admit  of  movements  by  which  the  screw  can 
take  any  position  required  in  the  various  degrees  of  elevation. 

217*  Chassis.  The  chassis  is  the  movable  railway  on  which 
the  top-carriage  moves  to  and  from  battery.  It  is  composed  of 
two  wrought-iron  rails  inclined  three  degrees  to  the  horizon,  and 
united  by  transoms,  as  in  the  top-carriage.  In  addition  to  the 
transoms,  there  are  several  diagonal  braces,  to  give  stiffness  to 
the  chassis.     (Fig.  1,  Plate  VIIL) 

For  the  10-inch  gun  and  all  smaller  carriages,  the  chassis  rails 
are  single  beams  of  rolled  iron,  15  inches  deep ;  for  all  calibres 
above,  the  mils  are  built  up  of  long  rectangular  pieces  of  boiler 
plate  and  T-iron,  in  a  manner  similar  to  that  of  the  cheeks  of 
the  top-carriage. 

Traverse-wheels.  The  chassis  is  supported  by  wheels,  which 
allow  of  its  having  a  horizontal  motion,  for  the  purpose  of  giv- 
ing the  piece  a  proper  direction  when  aiming. 

Traverse  circles.  The  traverse-wheels  roll  on  circular  bars 
of  iron  resting  on  a  bed  of  masonry  or  wood. 

Pintle.  This  is  an  upright  journal,  around  which  the  chassis 
traverses.  It  is  a  stout  c3THnder  of  wrought-iron,  inserted  in  and 
firmly  fastened  to  a  block  of  stone  called  the  pintle  block.  When 
wooden  platforms  are  used  it  is  fastened  as  described  in  par. 
635. 

The  centre-pintle  carriage  is  one  in  which  the  chassis  is  attach- 
ed to  the  pintle  at  its  middle,  and  revolves  around  it  through  the 
entire  circumference  of  the  circle.  The  traverse  circles  are  con- 
sequently continuous.  By  this  arrangement  a  much  greater 
horizontal  field  of  fire  is  secured. 

The  front-pintle  carriage  is  one  in  which  the  chassis  is  attached 
to  the  pintle  by  its  front  transom ;  the  traverse  circles  are  seg- 
ments of  circles. 

The  pintle  key  is  a  stout  key  of  iron  passing  through  the  pintle, 
to  prevent  the  chassis  from  jumping  oft'  when  the  piece  is  dis- 
charged. The  pintle  is  surrounded  by  a  plate  firmly  bolted  to 
the  block ;  this  plate  is  called  the  pintle  plate,  or  friction  plate. 


68  CABRIAGES. 

Hurters  and  counter-hurters.  These  are  flat  pieces  of  iron  bolt- 
ed,— the  first  to  the  front  and  the  latter  to  the  rear  part  of  the 
chassis  rails,  to  check  the  motion  of  the  top-carriage  when  the 
piece  is  run  in  battery*  and  when  it  recoils  upon  being  fired. 

In  carriages  of  improved  model  the  hurters  and  counter-hurt- 
ers are  stout  buffers  of  gutta-percha,  which,  absorbing  the  shock, 
prevent  racking  of  the  carriage. 

Guides  are  stout  claws  of  iron  bolted  to  the  cheeks  of  the  top- 
carriage,  and,  catching  under  the  flanges  of  the  chassis  rails,  pre- 
vent the  carriage  from  slipping  or  jumping  off. 

Through  the  chassis,  immediately  over  the  pintle,  runs  an 
eccentric  axle,  carrying  upon  each  end  a  truck- wheel.  This  axle 
and  wheels  are  for  the  purpose  of  throwing  the  chassis  in  gear, 
thus  raising  the  pintle  transom  from  the  friction  plate  and  allow- 
ing the  carriage  to  be  traversed  with  freedom. 

It  is  prescribed  that  the  chassis  shall  be  out  of  gear  when  the 
piece  is  fired.  This,  however,  is  not  necessary,  and  the  omission 
of  it  when  firing  saves  much  time  and  labor.  The  lighter  class 
of  carriages  are  without  the  arrangement  just  described. 

In  the  improved  pattern  of  carriages  the  axle  and  truck-wheel* 
above  mentioned  are  replaced  by  two  stout  rollers  attached  to* 
bolsters  on  the  front  end  of  the  chassis.  These  rollers  move  upon 
the  friction  plate,  and  give  firm  support  and  easy  motion  to  the 
chassis. 

Casemate  carriages  differ  from  barbette  carriages  in  being- 
much  lower,  but  their  mode  of  construction  is  essentially  the 
same.  The  pintle  is  placed  immediately  under  the  throat  of  the 
embrasure,  and  the  chassis  is  connected  to  it  by  a  bar  of  iron 
called  the  tongue. 

Recoil  checks.  For  the  10-inch  smooth-bore  and  all  below  that 
calibre,  recoil  is  checked  simply  by  the  inclination  of  the  chassis 
rails  and  the  sliding  friction  thereon  of  the  top-carriage.  To 
increase  this  friction,  the  rails  should  be  sanded  with  sand  free 
from  pebbles. 

218*  Pneumatic  buffers  or  air-cylinders  are  devices  for  check- 
ing recoil  through  the  agency  of  atmospheric  air.  At  present, 
only  the  15-inch  gun  is  thus  provided. 

Between  the  front  ends  of  the  chassis  rails  are  attached  two 
cast-iron  cylinders  each  110  inches  long,  with  an  interior  diame- 
ter of  14.25  inches.  The  ends  of  the  cylinders  are  closed  with 
tight-fitting  heads  secured  with  screw  bolts.  A  piston  works  in 
each  cylinder.  The  rods  of  the  pistons  pass  out  through  the  rear 
cylinder  heads  and  are  attached,  by  nuts,  to  a  heavy  transom  on 
the  rear  end  of  the  top-carriage.    The  cylinders  have  the  same 


CARRIAGES.  69 

inclination  as  the  chassis  rails,  and  arc  secured  to  the  latter  by 
three  cylinder  transoms. 

When  the  piece  recoils  the  piston-rod  is  withdrawn,  and  the 
air  contained  in  the  cylinder  compressed  between  the  piston  and 
the  rear  head  of  the  cylinder.  A  small  hole  in  the  front  head 
admits  air  to  supply  the  vacuum  in  front  of  the  piston. 

The  air  in  rear  of  the  piston  thus  forms  an  elastic  cushion, 
offering  but  slight  resistance  to  the  first  movement  of  recoil,  but 
gradually  increasing  in  resisting  force  as  the  carriage  moves 
back,  until  finally  the  force  of  recoil  is  overcome  and  the  top- 
carriage  is  brought  to  a  state  of  rest.  The  shock  of  recoil  is  to 
a  great  extent  absorbed  without  sudden  strain  to  the  carriage. 

The  top-carriage  must  be  out  of  gear  when  the  piece  is  dis- 
charged ;  it  then  moves  on  the  chassis  with  sliding  friction.  This, 
together  with  the  inclination  of  the  chassis  rails,  assists  in  check- 
ing the  recoil.  When  the  carriage  is  in  good  running  order,  it 
generally  runs  forward  a  short  distance  by  the  reaction  of  the 
compressed  air  after  recoil. 

To  run  the  piece  in  battery,  the  top-carriage  is  thrown  into 
gear;  it  then  moves  forward,  the  air  is  compressed  in  front  of 
the  pistons,  and,  escaping  gradually  through  the  small  holes  in 
the  heads  of  the  cylinders,  allows  the  carriage  to  move  forward 
with  a  gentle  motion. 

The  weight  of  the  air-cylinders  with  attachments  is  about 
5000  pounds. 

219.  Hydraulic  buffer.  This  is  a  recoil  check,  in  construction 
very  similar  to  the  air-cylinder.  A  liquid  is  used  instead  of  air, 
but  the  principles  of  operation  are  similar. 

At  present  these  buffers  are  furnished  only  with  the  (convert- 
ed) 8-inch  rifle,  and  are  described  in  connection  therewith. 
(See  par.  3*20.)  Water  or  any  oth<*r  free- flowing  liquid  answers 
for  filling  the  cylinder.  In  cold  weather  a  non-freezing  liquid, 
as  a  mixture  of  glycerine  and  water,  methyl  and  water,  or  some 
of  the  non-freezing  oils,  must  be  used.  The  greatest  care  must 
be  observed  to  have  in  the  cylinder  the  exact  amount  required. 
The  difficulty  of  properly  regulating  all  of  these  matters  makes 
the  hydraulic  buffer  greatly*! nferior  to  the  air-cylinders. 

220.  Friction  bars.  This  device  for  absorbing  recoil  is  sup- 
plied only  with  the  experimental  8-inch  rifle  (converted).  It  is 
described  injsar.  320. 

22l9  Depressing  carriages.  These  are  carriages  that  permit 
foe  gun  to  lire  over  a  parapet  in  the  usual  manner,  and,  upon 
ecoil,  allow  the  piece  to  descend  behind  the  parapet,  where  it 
an  be  reloaded  in  safety. 


70  CARRIAGES. 

Various  plans  for  effecting  this  have  been  proposed,  but  none 
actually  adopted,  in  the  U.  S.  service.  The  King  carriage, 
mounting  a  15-inch  gun,  has,  however,  been  tested  and  found 
to  work  efficiently.  This  consists  in  lowering  the  rear  end  of 
the  chassis  until  it  nearly  touches  the  ground,  thus  forming  an 
inclined  plane  at  an  angle  of  about  30°  to  the  horizon.  The  top- 
carriage  is  attached  to  a  counterpoise  by  a  band  composed  of 
wire  ropes  This  counterpoise  is  a  heavy  mass  of  metal  descend- 
ing into  a  well  in  front  of  the  pintle. 

The  carriage  that  has  been  adopted,  and  hereafter  to  be  fur- 
nished for  barbette  service,  has  an  increase  of  15  inches  in 
height  over  those  of  old  pattern.  This  modification  is  effected  by 
inserting  sections,  similar  in  construction  to  the  chassis  rail,  be- 
tween the  rails  and  feet,  props,  and  fork  of  the  low  chassis.  The 
increase  of  height  thus  gained  admits  of  a  corresponding  depres- 
sion of  the  terre-plein,  and  consequently  greater  protection  be- 
hind the  parapet  for  the  cannoneers.  The  gun,  nevertheless,  is 
exposed  as  before.  Depressing  carriages  are  intended  to  protect 
the  piece  and  carriage  as  well  as  the  cannoneers. 

The  accuracy  of  modern  artillery  fire  increases  the  danger  to 
the  guns  with  which  a  work  is  armed;  and  the  disabling  of  a 
piece  by  the  enemy's  fire  is  of  greater  moment  now  than  for- 
merly, when  works  were  garnished  with  a  greater  number,  and 
of  such  small  size  as  to  be  readily  replaced  when  injured. 

222,  Mortar  carnages.  These  are  constructed  and  put  to- 
gether in  a  manner  similar  to  the  top-carriages  for  guns.  At 
the  ends  of  each  cheek  are  projections,  called  front  and  rear 
notches',  underneath  which  the  cannoneers  embar  with  their 
handspikes  to  move  the  carriage.  On  those  for  siege  mortars 
there  are  also  two  front  and  two  rear  manoeuvering  bolts  for  the 
same  purpose.  The  bottom  part  of  each  cheek,  resting  on  the 
platform,  is  called  the  shoo  ;  the  front  and  rear  ends  being  desig- 
nated the  toe  and  heel,  respectively. 

Carnages  for  siege  mortars  are  without  truck-wheels,  and  rest 
directly  on  the  platform.  Sea-coast  mortars  have  two  truck- 
wheels  on  an  eccentric  axle,  for  manoeuvering  the  carriage  on 
the  platform,  and  manoeuvering  bolts  are  omitted.  (Figs.  1,  2, 
3,  4,  Plate  IX.) 

The  centre -pintle  mortar  carriage  is  described  in  par.  370. 

223.  The  flank-casemate  carriage  ( Fig.  2,  Plate  VIII)  con- 
sists of  two  cheeks  of  wood  united  by  two  iron  transoms.  The 
chassis  consist  of  two  wooden  rails  three  inches  apart,  and  joined 
by  four  transoms  and  assembling  bolts. 

To  the  rear  end  of  the  top-carriage  is  attached  an  eccentric 


PLATFORMS.  71 

roller,  and  to  each  cheek,  in  front,  a  roller  which,  when  the 
eccentric  roller  is  in  gear*  rests  on  the  chassis  rail?,  giving  to 
the  carriage  rolling  friction.  The  piece  is  then  easily  run  in  and 
out  of  battery,  the  cannoneer*  applying  themselves  to  ring*  and 
handles  on  the  sides  of  the  checks. 

The  front  end  of  the  chassis  rests  on  the  solo  of  the  embrasure, 
and  is  provided  with  a  lunette,  through  which  a  pintle  drops  into 
the  masonry  beneath.  The  rear  of  the  chassis  is  supported  by 
an  iron  fork,  to  the  lower  extremity  of  each  prong  of  which  is 
attached  a  small  traverse- wheel. 

For  description  of  traveling  gun  carriages,  see  Siege  Gun, 
par.  231,  et  seq. 

PLATFORMS. 

224.  To  insure  accuracy  of  fire  with  heavy  guns  and  mortars, 
it  is  absolutely  necessary  to  have  solid  and  substantial  platforms. 

For  casemate  and  barbette  batteries  in  fortifications,  fixed 
platforms  are  constructed  with  the  works. 

The  barbette  platform  consists  essentially  of  the  pintle  block, 
which  is«of  granite  firmly  imbedded  in  concrete;  in  the  block  is 
inserted  the  pintle,  of  iron,  and  around  this  is  the  friction  plate 
for  the  pintle  transom  of  the  chassis  to  rest  upon.  Traverse 
circles,  of  iron,  form  level  and  smooth  tracks,  upon  which  the 
traverse- wheels  run. 

The  pintle  of  a  casemate  carriage  is  inserted  in  a  hole  in  the 
sole  of  the  embrasure,  and  is  lifted  out  when  the  chassis  U  to  be 
removed.  The  chassis  is  attached  to  it  by  a  tongue,  and  is  pro- 
vided with  a  front  set  of  traverse-wheels. 

Platforms  for  siege  pieces  are  supplied  by  the  Ordnance  De- 
partment, and,  as  they  accompany  troops  in  the  field,  it  is 
desirable  to  have  them  as  light  as  is  compatible  with  sufficient 
strength  to  endure  the  shock  of  firing.  Those  hereafter  describ- 
ed combine,  in  a  high  degree,  the  essential  qualities  of  strength 
and  portability.  All  the  pieces  composing  them  arc  of  the  same 
dimensions,  and,  as  the  weight  of  each  piece  is  only  fifty  pounds, 
a  soldier  can  carry  one  from  the  depot  to  the  batteries,  or  any 
moderate  distance,  in  addition  to  his  arms  and  equipments. 

Another  platform  for  mortars  is  described,  which  is  very  sim- 
ple, strong,  and  well  suited  to  positions  where  trees  or  timber 
can  be  easily  procured.    This  is  designated  the  rail  platform. 


72 


PLATFORMS    FOR    SIEGE   GUNS. 


Platform  for  a  Siege  Gun  or  Howitzer. 

(Fig.  1 ,  Plate  X.) 
225*  Dimensions,  &c,  of  siege  platforms. 

Guns  and  howitzers. 


Names  of  Pieces. 

No.  of 
pieces. 

C 

CO 

•d 

CO 
CO 

d 
.** 

• 

•a 

•H 

I* 

Kind  of  Timber 
Used. 

1 

12 
36 

4 

Inch. 

108 

108 

108 

48 

32 

Inch. 

5 
5 
5 
3.5 
2 

Inch. 

3.5 
3.5 
3.5 

2 

1 

Lbs. 

51 

612 

1836 

70 

10 

►Yellow  pine. 
j 

Deck-Dlanks 

Stakes  (securing) 

Stakes  (implement).. 

Eye-bolts  (iron) 

4 

14 

0.75 

r'nd 

•■••••••a 

2579 

■ 

i 

i 
.  _    i 

When  the  piece  is  to  be  fired  constantly  in  one  direction,  it  is 
best  to  give  the  platform  an  inclination  to  the  rear.  This  pre- 
vents excessive  recoil,  and  also  serves  to  cany  oft"  water  from 
rain.  The  degree  of  inclination  is  not  absolute.  In  the  follow- 
ing it  is  given  as  one  and  a  half  inches  to  the  yard. 

When  the  piece  is  to  be  traversed  over  a  wide  field  of  fire,  the 
platform  should  be  perfectly  level ;  the  recoil  is  then  checked 
by  placing  a  bag  of  earth  or  a  pile  of  sods  at  a  proper  distance 
(about  five  feet)  behind  each  wheel. 

The  following  is  the  method  of  laying  the  platform  when  it 
has  an  inclination.  To  lay  it  horizontally,  simply  omit  what  is 
said  with  reference  to  the  slope : 

The  direction  in  which  the  piece  is  to  fire  is  established  by 
stretching  a  cord  over  the  centre  of  the  place  where  the  plat- 
form is  to  be  laid.     This  line  is  the  directrix  of  the  platform. 

Prepare  a  bed  for  the  platform  by  excavating  the  earth  so 
that  it  will  have  the  proper  inclination  to  the  rear  and  be  per- 
fectly level  across.  The  earth,  if  not  already  4irm,  should  be 
well  rammed. 

Lay  the  outside  sleepers  parallel  to  the  directrix,  their  outside 
edges  being  fifty-four  inches  distant  from  it.  The  four  other 
sleepers  are  laid  parallel  to  these,  the  edge  of  each  fifteen  and  a 


PLATFORMS   FOR   8IBOE   GUNS.  78 

half  inches  from  the  edge  of  the  next.  The  upper  surface  of 
the  front  ends  of  these  sleepers  is  fifty  inches  below  the  sole  of 
the  embrasure,  and  they  are  laid  with  an  elevation  to  the  rear 
of  one  and  a  half  inches  to  the  yard,  or  four  and  a  half  inches 
in  their  whole  length.  This  elevation  is  determined  by  placing 
a  block  four  and  a  half  inches  high  on  the  front  end  of  the 
sleeper,  and  laying  a  straight-edge,  with  a  level  on  it,  from  this 
block  to  the  rear  end ;  the  earth  is  then  arranged  so  as  to  bring 
the  level  true  in  this  position. 

The  next  set  of  sleepers  are  laid  against  and  inside  of  the  first, 
overlapping  them  three  feet,  having  the  rear  ends  inclined  out- 
wards, so  that  the  outer  edges  of  the  exterior  ones  shall  each  be 
fifty-four  inches  from  the  directrix,  and  the  space  between  the 
rear  edges  of  the  others  the  same  as  in  the  first  set,  viz.,  fifteen 
and  a  half  inches  from  the  edge  of  one  to  the  edge  of  the  next : 
all  having  an  elevation  to  the  rear  of  one  and  a  half  inches  to 
the  yard,  and  perfectly  level  across.  The  earth  is  then  rammed 
lirmly  around  the  sleepers  and  made  even  with  their  upper 
surface.  The  first  deck-plank,  with  a  hole  through  each  end  for 
the  eye-bolts,  is  laid  in  place,  perpendicular  to  the  directrix,  its 
holes  corresponding  with  those  in  the  sleepers.  The  hurter  is 
placed  on  it,  and  the  bolts  driven  through  the  corresponding 
boles  in  these  pieces.  The  hurter  should  be  so  placed  as  to  pre- 
vent the  wheels  from  striking  against  the  cpaulment  when  the 
piece  is  in  battery. 

If  the  interior  slope  has  a  base  of  two-sevenths  of  its  height, 
the  inner  edge  of  the  hurter  should  be  two  and  a  half  inches 
from  the  foot  of  the  slope.  The  other  planks  are  laid,  each  be- 
ing forced  against  the  preceding,  with  the  dowels  fitting  into 
their  respective  holes ;  the  last  plank  has  holes  for  the  eye-bolts. 
By  drawing  out  or  driving  in  the  outside  sleepers,  the  holes 
through  their  rear  ends  are  made  to  correspond  with  those  in 
the  last  deck-plank.     The  bolts  are  then  driven. 

Drive  stakes  in  rear  of  each  sleeper,  leaving  their  tops  level 
with  the  upper  surface  of  the  platform.  Raise,  ram,  and  level 
the  earth  in  rear  of  the  platform,  so  as  to  have  a  plain  hard  sur- 
face to  support  the  trail  when  the  recoil  is  great. 

The  earth  should  he  raised  nearly  as  high  as  the  platform  at 
*he  sides,  and  well  rammed,  giving  it  a  slight  inclination  out- 

ird  to  allow  water  to  run  off.    The  platform  is  fifteen  feet 

ig  and  nine  feet' wide. 

nstead  of  twelve  sleepers,  each  nine  feet  long,  it  is  preferable 
use  six,  each  fifteen  feet  long. 


74 


FIELD   PLATFORM. 


226. 


Field  Platform. 

Dimensions,  fyc. 


Names  or 
Pieces. 


Hurter 

Sleepers 

Wheel-planks 

Trail-plank 

Eye-bolts 

Securing:  stakes. 

Total  weight... 


• 

n 

• 

to 

o.  of 
piece 

• 

so 

o 

+3 

si 
to 

Q 

K 

^ 

Inch. 

Inch. 

Inch. 

Lbs. 

1 

96 

5 

:*.5 

44 

4 

108 

5 

3.5 

204 

2 

120 

13 

2.25 

160 

1 

81 

13 

2.25 

60 

9 
8 

14 

48 

0.75 
1.25 

r'nd 
1.25 

32 

500 

•n 


Kind  of  Tdcbbr 
Used. 


Yellow  pine. 

Yellow  pine. 

Beech,  yel.  pine  or  oak. 

Beech,  yel.  pine  or  oak. 

Iron. 

Hickory  or  oak. 


(Fig.  2,  Plate  X.) 

This  platform  is  for  siege  guns  and  howitzers  when  serving 
with  an  army  in  the  field,  and  the  method  of  constructing  it 
indicates  the  way  in  which  platforms  maybe  extemporized  from 
such  material  as  may  be  at  hand. 

To  lay  this  platform,  level  off  the  ground  and  mark  the  di- 
rectrix; dig  trendies  for  the  sleepers;  place  the  latter  in  the 
trenches  so  that  the  holes  for  the  eye-bolts  will  correspond  in 
place  to  those  in  the  wheel-planks;  place  the  wheel-planks  in 
position,  and  drive  in  the  eye-bolts.  The  front  eye-bolts  pass 
through  and  secure  the  hurter;  apply  the  level  and  make  the 
structure  perfectly  level;  secure  the  front  sleeper  with  stakes; 
it  is  well  to  secure  also  the  rear  ends  of  the  wheel-planks  with 
stakes;  lay  on  the  trail-plank  and  secure  it  with  an  eye-bolt  to 
the  third  sleeper;  ram  the  dirt  well  in  around  the  sleepers. 

To  check  recoil,  place  sacks  of  earth  or  piles  of  sods  over  the 
eye-bolts  of  the  third  sleeper,  or  a  stick  of  timber,  similar  to  a 
sleeper,  laid  across  will  effect  the  same  object. 

This  platform  admits  a  change  of  direction  of  about  ten  de- 
grees on  each  side  of  the  directrix,  thus  covering  as  much  of  a 
field  of  fire  as  is  ordinarily  required.  To  make  this  change  of 
direction,  slightly  loosen  or  remove  the  earth  about  the  three  rear 
sleepers,  and  hejive  the  rear  ends  of  the  wheel-planks  over  with 
handspikes.  The  platform  then  has  the  position  indicated  by 
the  dotted  lines  in  the  figure. 


8IEGE   MORTAR   PLATFORM. 


75 


227. 


Siege  Mortar  Platform. 


Names  of  Pieces. 

• 

o 

Pi 

o 

• 

I 

i 

« 
Hi 

8 
a> 

S 

i 

• 

KncD  or  Timber 
Used. 

« 

21 
6 
4 

12 

Inch. 

105 

108 

48 

48 

11 

Inch. 

5 
5 

3.5 

1 

.75 

Inch. 

3.5 
3.5 
2 
1 
r'nd 

Lbs. 

252 

1070 

70 

•Yellow  pino. 

J 

Stakes  (securing).... 
Stakes  (pointing).... 
Eye-bolts  (iron). ...... 

(Fig.  3,  Plate  X) 

This  platform  is  composed  of  six  sleepers  and  twenty-one- 
deck-planks.  It  is  laid  level,  and  the  front  and  rear  deck-planks- 
are  connected  by  eye-bolts  to  each  sleeper.  A  bed  for  the  plat- 
form is  first  prepared  by  leveling  oil"  the  ground,  and,  if  not 
already  solid,  the  earth  should  be  well  rammed.  This  bed 
should  be  sunk  only  so  deep  as  to  allow  the  upper  surface  of  the 
platform  to  be  slightly  above  the  surrounding  ground,  for  drain- 
age. The  sleepers  are  laid  parallel  to  the  directrix  or  plane  of 
fire,  three  on  each  side  of  it,  at  equal  distances  apart,  so  that  the 
holes  in  their  ends  shall  correspond  to  the  holes  in  the  front  and 
rear  deck-planks.  The  front  deck-plank  is  laid  first,  and  the 
eye-bolts  driven  to  secure  it;  the  remaining  planks  are  driven 
up  against  it,  and  the  last  secured,  like  the  first,  with  eye-bolts. 
At  the  rear  end  of  each  sleeper  a  securing  stake  is  driven. 

The  earth,  on  all  sides,  should  be  raised  nearly  as  high  as  the 
platform,  and  well  rammed,  giving  it  a  slight  inclination  out- 
wards, to  allow  the  water  to  ruu  on. 

It  is  of  the  first  importance  that  the  upper  surface  of  the  plat- 
form should  be  level  and  true. 


76 


RAIL   PLATFORM. 


Rail  Platform  fob  Siege  Mortars. 

{Fig.  4,  Plate  X.) 
228.  Dimensions,  &c,  of  the  rail  platform. 


Names  of  Pieces. 


Sleepers 

Rails 

Stakes  (securing).... 
Platform  complete.. 


Siege  Mortars. 

• 
CO 

« 

o 

• 

CD 

00 

•<•* 

CO 

P. 
«H 

o 

• 

• 

fee 

• 

• 

1 

CD 

g 

CD 

Inch. 

Inch. 

Inch. 

Lbs. 

2 

60 

11.5 

8.5 

••••••••• 

2 
14 

108 
48 

10 
3.5 

10 
3 

825 

Kind  of  Timbxb 
Used. 


Yellow  pine. 


This  platform  consists  of  three  sleepers  and  two  rails  for  the 
shoes  of  the  mortar  to  rest  on.  It  is  very  strong,  and  easily 
•constructed  and  laid. 

The  rails  and  sleepers  are  notched  and  fitted  together  as  rep- 
resented in  the  figure.  The  distance  between  the  centre  lines  of 
the  rails  is  equal  to  that  between  the  centre  lines  of  the  cheeks 
of  the  mortar  carriage.  The  pieces  are  put  together  at  the  bat- 
tery, and  the  earth  is  excavated  eight  inches  in  depth,  and  of 
suitable  length  and  width  to  receive  the  platform.  The  bottom 
of  this  excavation  is  made  perfectly  level.  The  directrix  being 
accurately  marked  by  stakes,  the  platform  is  placed  in  position, 
its  centre  line  coinciding  with  a  cord  stretched  between  the 
stakes  marking  the  directrix.  The  earth  is  filled  in  as  high  as  the 
upper  surface  of  the  sleepers  and  firmly  rammed;  stakes  are 
•driven  in  the  rear  angles  formed  by  the  sleepers  and  the  rails, 
and  one  at  the  rear  end  of  each  rail. 


PLATFORMS   FOR   SEA-COAST   MORTARS. 


77 


Platforms  for  Sea-ooast  Mortars. 

lZ-inch  mortars. 

M9.  The  size  of  the  platform  is  15  feet  by  15  feet  by  2  feet 
2  inches. 

Dimensions  of  parts. 


Names  of  Pisces. 


Deck- timbers 

Sleepers 

Bolts 

Nuts 

"Wood  screws 

Iron  plates -I 

Planking 


<0 

o 


15 
15 
56 
56 

501 
2 

or  3 
15 


i 

a 
h4 


Inch. 

180 

180 

24 

1 

3 
180 
180 
180 


§ 

a 

s 

2 

Inch. 

Inch. 

12 

12 

12 

12 

1 

r'nd 

2 

2 

5.16 

r'nd 

54 

0.5 

36 

0.5 

12 

2 

RXMAJMCS. 


The  timber  for 
these  platforms  to 
be  of  oak,  or  heart 
yellow  pine. 


Note. — The  above  is  the  thickness  of  the  iron  plates  furnished  ; 
but  they  are  entirely  too  thin,  curling  up  with  the  weight  of  the 
mortar.    They  should  be  at  least  0.75  inch  thick. 

To  lay  the  platform,  a  pit  is  dug  2  feet  deep  and  about  18  feet 
square  on  the  bottom.  The  earth  on  the  bottom  is  well  rammed 
and  levelled.   The  two-inch  planking  is  laid  level  on  the  rammed 
earth,  perpendicular  to  the  directrix.    The  cylindrical  bolts  are 
put  iu  the  sleepers,  and  the  sleepers,  with  bolt-heads  down,  are 
laid  compactly  on,  and  perpendicular  to  the  planking  and  par- 
allel to  the  directrix.   As  the  deck-timbers  are  laid  the  bolts  pass 
through  the  holes  in  them.    These  timbers  are  laid  compactly 
upon  the  sleepers,  perpendicular  to  the  directrix.    The  nuts  are 
put  on  the  bolts  and  screwed  down.    Both  the  nut  and  bolt- 
heads  are  countersunk.    The  iron  plates  are  laid  parallel  to  the 
directrix,  and  secured  firmly  with  screws  to  the  deck-timbers, 
vering  nine  feet  in  the  centre  of  the  platform  and  leaving  three 
t  on  each  side  uncovered.    The  earth  is  then  filled  in,  and 
nmed  compactly  around  the  platform,  with  a  slight  inclina- 
n  outwards,  so  as  to  shed  water.    The  platform  for  the  ccn- 
-pintle  chassis  is  17  feet  square ;  the  bottom  of  the  pit  must 
refore  be  20  feet  square. 


78 


PLATFORMS   FOR   SEA-COAST   MORTARS. 


10-inch  sea-coast  mortar. 

The  size  of  this  platform  is  12  feet  by  12  feet  by  1  foot  8 
inches. 

Dimensions  of  parts. 


Names  of  Pieces. 


Deck-timbers 

Sleepers 

Bolts 

Nuts 

Wood  screws 
Iron  plates... 
Planking: 


• 

00 

• 

<u 

to 

.of 
piec 

& 

1 

o 

0) 

t-1 

is 

Inch. 

Inch. 

Inch. 

12 

144 

12 

9 

12 

144 

12 

9 

44 

18 

1 

r'nd 

44 

1 

2 

2 

204 

3 

5.16 

r'nd 

2 

144 

48 

0.5 

12 

144 

12 

2 

Remarks. 


The  timber  for 
these  platforms  to 
be  of  oak,  or  heart 
yellow  pine. 


To  lay  the  platform,  a  pit  is  dug  1  foot  6  inches  deep  by  15  feet 
square;'  tiie  remainder  of  the  operation  is  similar  to  that  for  tho 
13-inch  mortar. 

For  descriptions  of  wooden  platforms  for  sea-coast  guns,  see 
par.  635. 


fart  £wn&. 


SERVICE  OF  THE  PIECE. 

The  service  of  the  piece  consists  of  all  the  operations  required 
in  loading,  pointing,  and  discharging  it. 

General  Rules. 

230.  To  avoid  repetitions,  and  to  secure  easy  reference,  the 
following  general  rules  are  inserted  collectively.  The  para- 
graphs referred  to  belong  to  some  particular  piece — generally 
the  siege  gun — and  illustrate  the  application  of  the  rule. 

I.  The  implements  and  equipments  required  for  a  piece  are 
taken  to  it  by  the  detachment  when  going  to  the  exercises,  or 
they  may  be  placed  there  previous  to  that  time. 

They  are  removed,  at  the  conclusion  of  the  exercises,  by  the 
same  means,  and  returned  to  their  proper  places  in  the  store- 
house. 

It  is  the  especial  duty  of  the  chief-of-detachment  to  see  that 
all  that  appertains  to  his  piece  is  complete  and  in  good  order. 

II.  At  the  conclusion  of  the  exercises,  and  previous  to  leaving 
a  battery,  the  officer  in  charge  will  dress  it,  giving  the  pieces,  on 
the  same  line,  a  uniform  alignment,  direction,  and  depression. 
Pieces  must  never  be  left  loaded. 

III.  The  detachments  are  marched  to  the  battery,  and  the 
cannoneers  posted  at  their  pieces  as  prescribed  in  par.  106. 

IV.  When  the  equipments  are  distributed,  the  gunner  buckles 
the  strap  of  his  pouch  around  his  waist,  wearing  the  pouch  in 
such  position  as  to  interfere  as  little  as  possible  with  his  move- 
ments. 

The  cannoneer  who  wears  it,  buckles  on  the  primer-pouch  in 
like  manner. 

The  gunner  removes  the  vent-cover,  and  clears  the  vent  with 
the  priming-wire. 

Cartridge-pouches  are  carried  suspended  from  the  left  shoulder 
to  the  right  side.    (Par.  256.) 

V.  In  loading,  the  gunner  closes  the  vent  by  applying  the 
cond  finger  of  the  left  hand  tightly  upon  it,  and  holding  it 
ere  from  the  moment  the  sponge  is  introduced  in  the  muzzle 
itil  the  rammer  is  withdrawn  after  the  projectile  is  home. 

V.  238.) 

VI.  When,  in  loading,  the  sponge  or  the  rammer  is  found  to 

(79) 


80  GENERAL   RULES. 

be  home  at  the  fourth  motion,  then  what  is  prescribed  for  the 
sixth  will  be  executed  at  the  fourth.    {Par.  239.) 

VII.  In  sponging  or  in  ramming,  the  knee  on  the  side  toward 
which  the  effort  is  made  is  always  bent,  the  other  straightened. 
The  weight  of  the  body  is  added,  as  much  as  possible,  to  the 
effort  exerted  by  the  arms.     {Par.  239.) 

VIII.  When  the  sponge  fits  so  tightly  as  to  be  difficult  to 
move  in  the  bore,  Nos.  1  and  2  may  use  both  hands  in  inserting 
and  withdrawing  it.     [Par.  240.) 

IX.  Cartridges  are  inserted  into  the  bore,  bottom  foremost 
and  seams  to  the  sides.     {Par.  240.) 

X.  All  projectiles  having  fuses  are  inserted  in  the  bore  so  that 
the  fuse  shall  be  towards  the  muzzle.    {Par.  241.) 

XI.  A  primer  is  prepared  for  insertion  in  the  vent  b}'  holding 
it  between  the  thumb  and  forefinger  of  the  left  hand ;  the  lan- 
yard, wound  upon  its  handle,  is  held  in  the  right  hand,  the  hook 
by  the  thumb  and  forefinger;  the  hook  is  attached  by  passing 
it  upward  through  the  eye  of  the  primer;  the  hook  and  primer, 
thus  attached,  are  held  by  the  thumb  and  forefinger  of  the  right 
hand ;  the  primer  is  pushed  into  the  vent  by  the  thumb. 

After  the  primer  has  been  inserted  in  the  vent,  the  cannoneer 
who  fires  the  piece  drops  the  handle,  allowing  the  lanyard  to 
uncoil  as  he  steps  back  to  the  position  from  which  he  is  to  fire; 
holds  the  handle,  with  the  cord  slightljr  stretched,  passing  be- 
tween the  middle  fingers  of  his  right  hand,  back  up,  and  breaks 
to  his  left  and  rear  a  full  pace  with  the  left  foot,  the  left  hand 
hanging  naturally  by  his  side.    {Par.  243.) 

XII.  In  aiming  guns  and  howitzers,  the  gunner  places  the 
breech  sight  in  its  seat  or  socket,  and  aims  through  it ;  gives  the 
proper  direction  by  causing  the  trail  to  be  moved,  commanding 
left  or  right,  tapping,  at  the  same  time,  on  the  right  side  of 
the  breech  for  the  trail  to  be  moved  to  the  left,  and  on  the  left 
side  for  it  to  be  moved  to  the  right.  The  cannoneers  at  the  trail 
will  closely  observe  the  motions  of  the  gunner.    {Par.  243.) 

With  mortars,  the  gunner  signals,  with  his  hands,  the  direc- 
tion in  which  he  wishes  the  carriage  moved.    {Par.  347.) 

When  the  piece  is  pointed,  the  gunner  raises  both  hands  as  a 
signal ;  the  cannoneers  moving  the  piece  then  unbar  and  resume 
their  posts. 

XIII.  At  the  command  Jire,  the  cannoneer  who  discharges 
the  piece  turns  his  face  from  it,  pulls  the  lanyard  quickty,  but 
steadily,  and  fires.  Immediately  after  the  discharge  he  resumes 
the  erect  position,  rewinds  the  lanyard  upon  its  handle,  returns 
it  to  his  pouch,  and  resumes  his  post.    {Par.  244.) 

XIV.  The  gunner,  after  pointing,  goes  where  he  can  best 
observe  the  effect  of  the  shot ;  after  which  he  resumes  his  post. 
(Par.  243.) 


GENERAL   RULES.  81 

XV.  Ammunition  is  not  used  when  exercising  by  the  num- 
bers.   (Par.  244.) 

XVI.  At  the  command  cease  firing,  pieces  that  are  loaded 
remain  so  until  further  orders ;  those  that  are  partly  loaded — if 
with  the  cartridge  only— the  cartridge  is  rammed  home ;  if  the 
projectile  has  been  inserted,  it  likewise  is  rammed  home.  In 
both  cases  the  priming-wire  is  left  in  the  vent,  as  an  indication 
that  the  piece  is  loaded. 

If  the  piece  is  not  loaded,  it  is  sponged  out.  All  the  cannon- 
eers resume  their  posts.     (Par.  247.) 

XVII.  When  ammunition  is  used,  the  instructor,  before  giv- 
ing the  command  load,  will  specify :  with  blank  cartridges — 
with  solid  shot — with  shell — with  case-shot.    (Par.  248.) 

XVIII.  To  secure  piece,  the  gunner  puts  on  the  vent-cover, 
and  No.  2  replaces  the  tompion  in  the  muzzle.     (Par.  249.) 

XIX.  Sponge  and  rammer  staves  are  permanently  marked 
with  a  white  ring,  to  show — with  the  sponge,  when  it  is  at  the 
bottom  of  the  bore;  with  the  rammer,  when  the  projectile  is 
home.     (Par.  253.) 

XX.  Rifle  projectiles  are  always  to  be  lubricated  previous  to 
loading.  They  are  then  easily  pushed  home,  and  their  range  and 
accuracy  are  increased.    (Par.  254.) 

XXI.  After  each  twentieth  discharge  (or  thereabouts)  with  a 
rifled  piece,  the  bore  is  washed  out  and  sponged  dry. 

XXII.  When  an  implement  is  taken  up  for  any  purpose  it  is 
returned  to  its  prescribed  place  by  the  person  using  it,  at  the 
completion  of  the  duty,  unless  otherwise  specified. 

XXIII.  Cannoneers  and  the  gunner  resume  their  proper  posts 
after  the  completion  of  any  duty,  unless  otherwise  especially 
directed. 

XXIV.  With  all  pieces  having  traversing  carriages,  pinch- 
bars  are  used  for  making  delicate  adjustments  in  pointing,  aud 
iron  wheel-chocks  for  holding  the  traverse-wheels  securely  in 
position.     (Par.  340.) 

XXV.  Gunners,  chief s-of -detachment,  and  chief s-of-platoon, 
give  or  repeat  commands  only  when  it  is  so  prescribed. 

XXVI.  The  habitual  post  of  the  chief-of- detachment  is  as 
specified  in  par.  106.  He  has,  under  the  instructor,  or  officer 
immediately  over  him,  general  supervision  of  all  duties  perform- 

il  by  his  detachment.  During  firings  he  looks  after  the  supply 
i  ammunition,  and  sees  that  those  engaged  in  preparing  and 
Irving  it  to  the  piece  perform  their  duties  properly. 

XXVII.  All  ammunition  must  be  prepared  for  firing  at  the 
rvice  magazine.  Projectiles  will  be  carefully  cleaned  of  all 
ist,  dirt,  or  protuberances  liable  to  cause  them  to  stick,  or  injure 
ie  bore. 


82  GENERAL  RULES. 

XXVIII.  In  the  service  of  a  battery  of  several  pieces,  the 
pieces  are  designated  Nos.  1,  2,  3,  &c,  from  right  to  left ;  these 
numbers  are  independent  of  the  permanent  numbers  assigned  to 
pieces  in  a  work. 

In  directing  the  pieces  to  be  fired,  they  are  always  designated 
by  their  battery  numbers ;  as,  Number  one — Fire  ;  Number  two — 
Fire,  &c. 

When  the  wind  comes  from  the  right,  the  firing  should  com- 
mence on  the  left,  and  reciprocally. 

XXIX.  Under  the  fire  of  the  enemy,  the  men  will  be  direct- 
ed to  cover  themselves  by  the  parapet  or  traverses  as  much  as 
may  be  consistent  with  the  execution  of  their  duties. 

XXX.  Previous  to  proceeding  with  any  exercise  with  the 
pieces,  and  frequently  at  other  times  during  the  exercises,  the 
instructor,  assisted  by  the  other  officers,  will  explain  to  the  men 
the  nomenclature  of  everything  appertaining  thereto ;  the  appli- 
cation and  use  of  the  various  parts,  machines,  and  implements 
used ;  the  names  and  use  of  the  different  parts  of  the  work  ad- 
jacent to  the  piece;  the  kinds  of  ammunition  used;  charges  of 
powder;  kinds  of  fire;  and,  generally,  all  matters  that  assUt  in 
making  the  men  efficieut  artillerists. 

XXXI.  In  time  of  actual  service,  in  front  of  an  enemy,  two 
or  more  detachments,  for  each  piece,  are  necessary,  and  all 
should  be  instructed.  These  detachments  will  be  designated 
First  relief,  Second  relief,  &c. ;  and  in  all  battery  formations,  as 
roll-calls,  parades,  &c,  will  fall  in  together  in  the  order  of  their 
numbers  from  right  to  left. 

XXXII.  In  aiming,  first  get  a  clear  view  of  the  object,  and 
see  that  the  piece  is  approximately  in  the  line  of  fire  before  look- 
ing through  the  sights ;  then  look  over  or  through  the  sights,  and 
if  the  object  be  not  in  the  line,  instantly  give  the  command  to 
move  the  trail  to  the  right  or  left. 

Always  aim  quickly,  as  the  eye  will  not  then  become  wearied. 

XXXIII.  The  prop  upon  which  the  sponge  and  rammer  are 
supported  is  a  low  trestle,  or  simply  a  block  of  wood  sufficiently 
high  to  prevent  the  sponge  taking  up  dirt  from  the  ground.  The 
rammer  is  always  laid  on  the  side  nearest  the  piece.    (Par.  233.) 

XXXIV.  To  prevent  the  projectile  from  starting  forward, 
guns  should  be  giveu  at  least  five  degrees  elevation  previous  to 
being  run  into  battery,  and  running  into  battery  should  be  done 
so  as  to  prevent  sudden  jar  against  the  hnrters.    (Par.  242.) 

XXXV.  In  case  the  friction-primer  explodes  without  discharg- 
ing the  piece,  care  must  be  taken  not  to  approach  the  piece  too 
soou — not  less  than  five  seconds — as  it  may  only  hang  fire,  and 
the  recoil  would  injure  any  one  in  the  way  of  it.    (Par.  252.) 

XXXVI.  Sponges,  after  the  first  fire,  should  always  be  moist- 


SERVICE   OF   SIEGE   GUN. 


88 


ened.  This  not  only  assists  id  extinguishing  any  fragments  of 
cartridge  that  might  remain  burning  in  the  bore,  but  it  prevents 
the  residuum  of  burnt  powder  from  hardening  on.  the  surface  of 
the  bore.  Fresh  water  is  preferable  to  salt  for  moistening  the 
sponge. 

XXXVII.  In  all  exercises  for  instruction,  duties  should  be 
performed  as  nearly  as  possible  as  in  actual  service,  and  not  by 
pretense  only.  To  do  this,  in  the  service  of  the  piece  a  dummy 
cartridge  should  be  used,  together  with  actual  projectiles.  The 
cartridge  may  be  made  of  canvas  or  stout  gunny-sacking,  tilled 
to  the  proper  weight  with  coal  broken  to  the  size  of  the  powder 
used  for  the  piece.  A  worm  serves  for  withdrawing  the  car- 
tridge. 

A  strong  lanyard  attached  to  the  fuse-plug  will  serve  to  with- 
draw the  projectile.  The  free  end  of  the  lanyard  remains  out  of 
the  muzzle  as  the  projectile  is  pushed  home. 


SERVICE   OF   SIEGE  GUN. 

{Fig.  1,  Plate  XL) 

Description  op  Piece. 

231.  Gun,  cast-iron;  muzzle-loading  rifle;  twist,  uniform, 
one  turn  in  15  feet. 

Number,  weights,  and  dimensions. 


Designation. 


Calibre ~. 

Length  of  piece 

Maximum  diameter 

Minimum  diameter , 

Length  of  bore  (calibres) ... 

Number  of  grooves 

Width  of  grooves 

Width  of  lands 

Depth  of  grooves 

Windage 

Initial  velocity  (feet) 

Charge  (cannon  powder) 

Solid  shot , 

Shell  (unfilled) 

Weight  of  piece 

Preponderance « 

Carriage  and  limber 

Piece,  carriage,  limber,  and  implements 

Horses  to  transport  (good  roads) 

44  "         (inferior  roads)-. ...~~.... 


No. 


26.5 
9. 


1280 


8. 
10. 


LB8. 


3.25 
85.5 
25. 
8570 
800 
3650 
7400 


Inch. 


4.5 
133. 
15.6 

9. 


0.97 
0.6 
0.075 
0.05 

•••••• 


84 


SERVICE    OF    SIEGE   GUN. 


The  nomenclature  of  the  carriage  for  the  siege  gun  and  siege 
howitzer  is  similar  to  that  for  light  field  pieces  as  laid  down  m 
"Light  Artillery  Tactics" ;  it  is  therefore  omitted  in  this  book. 

Ranges  in  yards. 


Elevation. 

Shot. 

Shell. 

Time  of 

Flight. 

1° 

0' 

» 

540 

533 

1.37 

1° 

30' 

790 

781 

2.05 

2°. 

0' 

1017 

1005 

2.69 

2° 

30' 

1240 

1224 

3.32 

3° 

0' 

1445 

1414 

3.94 

3° 

30' 

1639 

1593 

4.54 

4° 

1823 

1762 

5.14 

5° 

2170 

2071 

6.3 

6° 

2485 

2354 

7.42 

7° 

2780 

2610 

8.51 

8° 

3056 

2844 

9.57 

9° 

3313 

3061 

10.6 

10° 

3556 

3265 

11.59 

The  gun,  on  its  platform,  admits  of  9°  30'  elevation  and  10a 
30'  depression.  On  level  ground  it  admits  of  12°  elevation  and 
10°  depression.  By  digging  a  trench  for  the  trail  to  run  in,  a 
still  greater  elevation  may  be  obtained. 

In  works,  it  is  fired  from  a  wooden  platform.  {Par,  223.)  In 
the  field,  it  may  be  fired  without  a  platform,  when  the  ground 
is  level  and  firm ;  or  a  temporary  platform  may  be  extemporized 
from  such  beams,  planks,  or  logs  as  may  be  at  hand. 

To  serve  the  piece. 

232.  Eight  men  are  required  :  one  chief-of-detachment,  one 
gunner,  and  six  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 

}  Three  on  each  side  of  the  piece; 
leaning  against  the  parapet,  in 
line  with  cannoneers. 

IOne  yard  behind,  and  parallel  to 
the  cannoneers  of  the  right ;  sup- 
ported on  a  prop,  heads  turned 
from  the  epaulment. 


SERVICE   OF   SIEGE   GUN. 


85 


Pass-box Behind  and  near  No.  4. 

PrimPi-  nonrh  \  Containing  friction-primers and  lan- 

irimei-poucn f     yard .  8U8pended  from  caacaDie. 

««— rt  p— }  aaS1SS!t£SSrrini  eu8pcud- 

Steht  nonoh  \  Containing  breech  sight;  suspended 

*      H        /      from  cascable. 

Wheel-chocks }  <>^««gj  -*-  P«~.  near  the 

Vent-cover Covering  the  vent. 

Tompion In  the  muzzle. 

B  1  Leaning  against  the  parapet  near 

J       JNo.  «. 

Burlap  barrel  \  Containing  cartridges ;  at  a  safo  and 

isuage-oarrei f      convenient  place  near  the  piece. 

Sponge-bucket Near  sponge  and  rammer. 


In  filling-room  of  service  magazine. 


In  filling-room  of  service  magazine. 


Fuse-gauge 

Fuse-knife 

Fuse-wrench .., 

Fuse-reamer 

One  lanyard  (extra) 

233.  To  each  two  pieces  there  should  be 

One  worm 

One  hammer-wrench 

One  gunner's  quadrant... 

One  vent-punch 

One  vent-gimlet 

One  gunner's  level 

One  gunner's  pincers 

When  there  is  no  parapet,  the  handspikes  are  placed,  three  on 
each  side,  standing  between  the  cheeks  and  wheels  of  the  car- 
more,  in  front  of  and  resting  against  the  axle-tree. 

The  solid  shot  are  piled  on  the  left  of  the  piece  against  the  par- 
apet; the  other  projectiles  are  in  the  filling-room  of  the  service 
*nagazine ;  the  fuses,  cartridges,  and  primers  are  in  the  service 
naguzine. 

To  distribute  the  equipments. 

234.  The  instructor  commands :  1.  Take  equipments. 
The  gunner  steps  to  the  cascable;  takes  off  the  vent-cover, 
nding  it  to  No.  2  to  place  against  the  parapet  outside  of  his 


86  SERVICE   OF   SIEGE   GUN. 

post ;  gives  the  primer-pouch  to  No.  3 ;  equips  himself  with  the 
sight-pouch  and  his  own  pouch ;  clears  the  vent;  levels  the  piece, 
and  resumes  his  post. 

No.  3  equips  himself  with  the  primer-pouch.  These  rules  are 
general  for  all  guns. 

Nos.  1  and  2,  after  passing  two  handspikes  each  to  Nos.  3  and 
4,  take  one  each,  for  himself.  Nos.  5  and  6  receive  theirs  from 
Nos.  3  and  4. 

235.  The  handspike  is  held  in  both  hands,  diagonally  across 
the  body;  the  hand  nearest  the  parapet  grasping  it  near  the 
small  end  and  at  the  height  of  the  shoulder,  back  of  the  hand 
down,  elbow  touching  the  body;  the  other  hand  back  up,  the 
arm  extended  naturally ;  the  butt  of  the  handspike  resting  on 
the  ground,  on  the  side  of  the  cannoneer  farthest  from  the  para- 
pet, and  in  line  with  his  toes. 

236.  When  a  cannoneer  lays  down  his  handspike,  he  places 
it  directly  before  him,  about  six  inches  in  front,  and  parallel  to 
the  alignment,  the  small  end  toward  the  parapet;  and  whenever 
he  thus  lays  it  down  for  the  discharge  of  any  particular  duty,  he 
takes  it  up  after  having  completed  the  duty. 

23?.  The  service  of  the  piece  is  executed  as  follows:  The 
piece  being  in  battery,  the  instructor  commands : 

1.  From  battery. 

The  gunner  moves  two  yards  to  his  right. 

Nos.  1,  2,  3,  4,  5  and  6,  all  facing  from  the  parapet,  embar 
with  their  handspikes;  Nos.  1  and  2  under  the  front  of  the 
wheels;  Nos.  3  and  4  through  the  rear  spokes  of  the  wheels, 
near  the  felly,  under  and  perpendicular  to  the  cheeks;  Nos.  5 
and  6  under  and  perpendicular  to  the  manoeuvering  bolts. 

When  all  are  ready,  the  gunner  gives  the  command :  Heave. 
which  will  be  repeated  as  often  as  may  be  necessary,  and  sees 
that  Nos.  5  and  6  guide  the  trail  in  prolongation  of  the  directrix 
of  the  embrasure,  and  as  soon  as  the  face  of-  the  piece  is  about 
one  yard  from  the  parapet,  commands :  Halt,  at  which  all  un- 
bar and  resume  their  posts.  If  the  platform  has  a  slope,  Nos.  1 
and  2  chock  the  wheels  in  front. 

1.  By  the  numbers,  2.  Load. 

238.  Nos.  1,  2,  3,  and  4  lay  down  their  handspikes;  No.  2 
takes  out  the  tompion,  and  places  it  near  the  vent-cover. 

No.  L turns  to  his  left,  steps  over  the  sponge  and  rammer; 
faces  to  the  piece ;  takes  the  sponge  with  both  hands,  the  backs 
down,  the  right  hand  three  feet  from  the  sponge-head,  the  left 


SERVICE    OF   t->IE<;E   GUX.  87 

band  eighteen  inches  nearer  to  it;  return*  to  the.  piece.  entering 
the  staff  in  the  embrasure;  places  the  left  foot  in  line  with  the 
face  of  the  piece,  half-way  between  it  and  the  wheel ;  breaks  l<> 
the  right  with  the  right  foot,  the  heels  on  a  line  parallel  to  the 
piece,  the  left  leg  straightened,  the  right  knee  bent,  the  body 
erect  upon  the  hips,  and  inserts  the  sponge-head  in  the  muzzle: 
the  staff  in  prolongation  of  the  bore,  supported  by  the  right  hand, 
the  right  arm  extended,  the  left  hand  hanging  naturally  by  the 
side. 

No.  2  steps  to  the  muzzle,  and  occupies  a  position  on  the  left 
of  the  piece  corresponding  to  that  of  No.  1  on  the  right.  He 
seizes  the  staff  with  the  left  hand,  back  down,  near  to  ami  out- 
side the  hand  of  No.  1. 

No.  3  faces  about,  steps  over  the  rammer,  and  seizes  the  staff 
with  both  hands,  as  prescribed  for  No.  1  with  the  sponge,  and 
stands  ready  to  exchange  staves  with  No.  1 . 

No.  4,  taking  the  pass-box,  goes  for  a  cartridge  and  projectile  ; 
returns,  and  places  himself,  facing  the  piece,  about  eighteen 
inches  to  the  rear  and  right  of  No.  2. 

The  gunner  places  himself  near  the  stock,  his  left,  foot  ad- 
vanced; closes  the  vent  with  the  second  finger  of  the  left  hand, 
bending  well  forward  to  cover  himself  by  the  breech,  and  with 
the  elevating  screw  adjusts  the  piece  conveniently  for  loading. 

This  mile  for  closing  the  vent  is  general  for  all  guns  and  how- 
itzers. 

239.  In  the  meantime,  Nos.  1  and  2  insert  the  sponge  by 
tiie  following  motions,  at  the  commands  Two — Three — Four— 
Five— Six : 

Two.  They  insert  the  sponge  as  far  as  the  hand  of  No.  1, 
bodies  erect,  shoulders  square. 

Three.  They  slide  their  hands  along  the  staff  and  seize  it  at 
arm's-length. 

Four.    They  force  the  sponge  down  as  prescribed  for  two. 

Five.    They  repeat  three. 

Six.  They  push  the  sponge  to  the  bottom  of  the  bore.  No.  1 
replaces  the  left  hand  on  the  staff,  back  up,  six  inches  nearer 
the  muzzle  than  the  right;  No.  2  places  the  right  hand,  back 
up,  between  the  hands  of  No.  1,  and  both  then  quickly  change 
their  other  hands  so  as  to  seize  the  staff  with  the  back  of  the 
hand  up. 

If,  in  executing  these  motions,  or  the  corresponding  ones  with 
the  rammer,  it  be  found  that  the  sponge  or  rammer  is  at  home 
at  the  fourth  motion,  then  what  is  prescribed  for  the  sixth  mo- 
tion will  be  performed  at  the  fourth.     This  rule  is  general. 

The  knee  on  the  side  toward  which  the  effort  is  made  is  always 


88  SERVICE    OF    SIEGE    GUN. 

bent,  the  other  -straightened,  and  the  weight  of  the  body  added, 
as  much  as  possible,  to  the  effort  exerted  by  the  arms.  This  rule 
is  general. 

1.  Sponge. 

240.  Nos.  1  and  2,  pressing  the  sponge  firmly  against  the  bot- 
tom of  the  bore,  turn  it  three  times  from  right  to  left,  and  three 
times  from  left  to  right;  replace  the  hands  by  their  sides,  and 
withdraw  the  sponge  by  the  same  commands,  but  by  motions 
contrary  to  those  prescribed  for  inserting  it.  When  the  sponge 
fits  so  tightly  that  it  is  hard  to  move  in  the  bore,  Nos.  1  and  2 
may  use  both  hands.     This  rule  is  general. 

No.  2  quits  the  staff,  and  turning  towards  No.  4.  receives  from 
him  the  cartridge,  which  he  takes  in  both  hands,  and  introduces 
it  into  the  bore,  bottom  foremost,  seams  to  the  side;  he  then 
grasps  the  rammer  in  the  way  prescribed  for  the  sponge. 

This  rule,  with  reference  to  the  bottom  and  seams  of  the  car- 
fridge,  is  general. 

No.  1,  meanwhile,  rising  upon  both  legs,  turns  towards  his 
left;  passes  the  sponge  above  the  rammer  with  the  left  hand  to 
No.  3,  and,  receiving  the  rammer  with  his  right,  presents  it  a* 
prescribed  for  the  sponge,  except  that  he  rests  the  rammer-head 
against  the  right  side  of  the  face  of  the  piece. 

No.  3,  as  soon  as  the  sponge  is  withdrawn,  passes  the  rammer 
under  the  sponge  into  the  embrasure  with  the  right  hand;  re- 
ceives the  sponge  from  No.  1  with  the  left;  replaces  it  upon  the 
prop,  ami  resumes  his  post. 

No.  4,  setting  down  the  projectile  and  pass-box,  takes  out  the 
cartridge  and  hands  it  to  No.  2,  the  choke  to  the  front ;  returns 
the  pass-box  to  its  place,  and  takes  up  the  projectile. 

Nos.  1  and  2  force  home  the  cartridge  by  the  same  commands 
and  motions  as  for  the  sponge. 

1.  Kam. 

241.  Nos.  1  and  2  slide  their  hands  along  the  staff  to  the  full 
extent  of  their  arms;  grasp  it  firmly;  throw  the  weight  of  their 
bodies  upon  the  staff  and  press  the  cartridge  home.  No.  2  quits 
the  staff,  and  turning  towards  No.  4,  receives  from  him  the  pro- 
jectile. No.  1,  meanwhile,  throws  out  the  rammer,  and  holds  it 
with  both  hands,  the  head  against  the  right  side  of  the  face  of 
the  piece. 

No.  2,  receiving  the  projectile,  introduces  it  into  the  bore,  base 
foremost,  and  reseizes  the  staff  with  the  left  hand.  No.  4  re- 
sumes his  post. 


SERVICE   OF   SIEGE   GUN.  89 

Nos.  1  and  2  force  home  the  projectile  by  the  same  commands 
and  motions  as  prescribed  for  tiie  cartridge.  At  the  command 
ram  it  is  pressed  tightly  down  against  the  cartridge.  No.  2 
quits  the  rammer;  sweeps,  if  necessary,  the  platform  on  his  own 
side;  passes  the  broom  to  No.  1,  and  resumes  Ins  post.  No.  1 
throws  out  the  rammer,  and  places  it  on  the  prop  below  the 
sponge ;  sweeps,  if  necessary,  his  side  of  the  platform  ;  returns 
the  broom  to  No.  2,  and  resumes  his  post. 

The  gunner  pricks,  leaving  the  priming-wire  in  the  vent;  re- 
sumes his  post,  and  adjusts  the  breech  sight  to  the  distance  of 
the  object  to  be  fired  at. 

1.  In  battery. 

242*  Nos.  1  and  2  unchock  the  wheels,  (if  they  have  been 
chocked,)  and  with  Nos.  3,  4,  5,  and  6,  all  facing  towards  the 
epaulment,  embar;  Nos.  1  and  2  through  the  front  spokes  of  the 
wheels,  near  the  fellies,  under  and  perpendicular  to  the  cheeks  ; 
Nos.  3  and  4  under  the  rear  of  the  wheels,  and  Nos.  o  and  6 
under  and  perpendicular  to  the  stock,  near  the  trail.  All  being 
ready,  the  gunner  commands:  Heave,  and  the  piece  is  run  into 
battery,  Nos.  5  and  t>  being  careful  to  guide  the  muzzle  into  the 
middle  of  the  embrasure.  As  soon  as  the  wheels  touch  the  hurt- 
er,  he  commands :  Halt.  All  unbar,  and  Nos.  1,  2.  3,  and  4 
resume  their  posts. 

1.  Aim. 

243.  No.  3  lays  down  his  handspike ;  passes  the  hook  of  the 
lanyard  through  the  eye  of  a  primer  from  below  upward,  and 
holds  the  handle  of  the  lanyard  in  the  right  hand,  the  hook  be- 
tween the  thumb  and  forefinger.  This  rule  for  preparing  the 
primer  and  holding  the  lanyard  is  general. 

Nos.  5  and  6,  facing  towards  the  epaulment,  embar  under  and 
perpendicular  to  the  stock  near  the  manoenvering  bolts. 

The  gunner,  placing  himself  at  the  stock,  as  at  the  command 
toad,  withdraws  the  priming-wire ;  places  the  breech  sight  in 
its  socket;  sights  through  it,  and,  aided  by  Nos.  5  and  6.  gives 
the  direction,  causing  the  trail  to  be  moved  by  commanding 
T •1sft,  or  Right,  tapping,  at  the  same  time,  on  the  right  side  of 

e  breech  for  No.  5  to  move  the  trail  to  the  left,  or  on  the  left 

'e  for  No.  6  to  move  it  to  the  right;  and  by  the  elevating 

ew  gives  the  proper  elevation,  rectifying,  if  necessary,  the 

ection. 

The  moment  the  piece  is  correctly  aimed,  he  rises  on  the  left 
and  gives  the  command  Ready,  making  a  signal  with  both 


90  SERVICE   OF    SIEGE   GUN. 

hands,  at  which  Nos.  5  and  6  unbar  and  resume  their  posts. 
The  gunner,  taking  the  breech  sight,  goes  to  the  windward  to 
observe  the  effect  of  the  shot. 

These  rules,  as  to  the  method  of  aiming,  are  general. 

No.  3  inserts  the  primer  in  the  vent;* drops  the  handle,  allow- 
ing the  lanyard  to  uncoil  as  he  steps  back  to  his  post,  holding  it 
slightly  stretched  with  the  right  hand,  the  cord  passing  between 
the  middle  fingers,  back  of  the  hand  up,  and  breaks  to  his  left 
and  rear  a  full  pace  with  his  left  foot,  the  left  hand  hanging 
naturally  by  his  side. 

These  rules  for  holding  the  lanyard  and  breaking  off  by  the 
cannoneer  who  fires  the  piece  are  general. 

At  the  command  Ready,  Nos.  1  and  2,  laying  down  their 
handspikes,  take,  each,  a  chock  in  the  hand  nearest  the  epaul- 
meut,  and  breaking  off  sideways  with  the  foot  farthest  from 
the  epaulment,  stand  ready  to  chock  the  wheels  after  the 
recoil. 

1.  Number  one  (or  the  like),  2.  Fire. 

244.  No.  3,  turning  his  face  from  the  piece,  pulls  the  lanyard 
quickly,  but  steadily,  and  fires  the  piece. 

Immediately  after  the  recoil  of  the  piece,  Nos.  1  and  2  chock 
the  wheels  and  resume  the  erect  position ;  No.  3  resumes  the  erect 
position,  rewinds  the  lanyard  upon  its  handle,  returns  it  to  hU 
pouch,  and  resumes  his  post.  The  gunner  having  observed  th«» 
effect  of  the  shot,  returns  to  his  post. 

These  rules,  as  far  as  they  relate  to  the  cannoneer  who  discharges 
the  piece,  and  to  the  gunner,  are  general. 

Ammunition  is  not  used  when  exercising  by  the  numbers. 
This  rule  is  general. 

To  load  without  the  numbers. 

245.  The  instructor  commands :  Load. 

At  this  command  the  piece  is  run  from  battery,  loaded,  run 
into  batreiy,  and  prepared  for  firing  by  the  following  commands 
from  the  gunner:  From  battery— Load — In  battery — 
Aim— Ready. 

The  instructor  commands : 

1.  Number  one  (or  the  like),  2.  Fire. 

At  which  the  piece  is  discharged.  All  of  these  operations  are 
executed  as  before  explained,  except  that  Nos.  1  and  2  sponge 
and  ram  without  the  numbers. 


SERVICE   OF   SIEGE   GUN.  91 

To  load  and  fire  continuously. 
The  instructor  commands : 

1.  Commence^  2.  FIRING. 

246.  The  gunner  gives  the  same  command  as  in  the  preced- 
ing paragraph,  with  the  additional  one  of  Fire,  and  continues 
to  load  and  fire  until  the  instructor  commands : 

1.  Cease,  2.  Firing. 

247.  The  firing  then  ceases;  pieces  that  are  loaded  remain 
so  until  further  orders ;  those  that  are  partly  loaded — if  with  the 
cartridge  only,  have  the  cartridge  rammed  home;  if  with  the 
projectile,  it  likewise  is  rammed  home.  In  both  cases  tiie  prim- 
ing-wire is  left  in  the  vent.  If  the  piece  has  no  load  in  it,  it  is 
sponged  out;  all  the  cannoneers  then  resume  their  posts. 

If  it  is  intended  to  discontinue  the  firing,  the  instructor  directs 
the  chiefs -of -detachment  to  have  the  charges  withdrawn  and 
the  pieces  run  into  battery. 

These  rules  are  general. 

The  projectile  may  be  withdrawn  hy  depressing  the  muzzle 
and  raising  the  trail  until  the  muzzle  knocks  against  the  ground. 
Should  it  not  then  slide  out,  allow  the  piece  to  stand  until  (if 
the  atmosphere  is  moist)  the  residuum  of  burnt  powder  in  the 
bore  becomes  unctious;  then  depress  the  muzzle  and  raise  the 
trail  as  before.  If  the  projectile  still  refuses  to  slide  out,  the 
piece  will  have  to  be  discharged;  or  if  it  is  not  desirable  to  dis- 
charge it,  the  charge  may  be  drowned  ont  by  pouring  water  in 
at  the  muzzle,  afterwards  draining  it  out  and  pouring  a  small 
quantity  of  tine-grain  powder  in  at  the  vent  and  firing  it. 

Cartridges  are  withdrawn  bj'  means  of  the  worm. 

248.  Before  giving  the  command  load,  or  commence  firing , 
the  instructor,  when  ammunition  is  used,  will  specify :  with  blank 
cartridges — with  solid  shot — with  shell — or,  with  case-shot.  This 
rule  is  general. 

To  change  posts.     As  explained  in  par.  112. 

To  secure  piece. 
The  piece  being  in  battery,  the  instructor  commands : 

Secure  piece. 

249.  No.  2  replaces  the  tompion  in  the  muzzle.  The  gunner 
its  on  the  vent-cover^,  which  he  receives  from  No.  2,  and  de- 
•esses  the  muzzle,  ^^is  rule  is  general.  # 

/ 


32  ORGANIZATION   OF    SIEGE   GUN    BATTERY. 

To  replace  equipments. 
The  instructor  commands : 

Replace  equipments. 

250.  Nos.  I  and  2  replace  the  handspikes  against  the  para- 
pet, those  of  Nos.  3,  4,  5,  and  6  being  passed  to  them  by  Nos.  3 
and  4.     The  gunner  iiangs  the  pouches  on  the  cascable. 

To  serve  the  piece  with  reduced  numbers. 

251.  The  smallest  number  of  men  with  which  a  siege  gun 
can  be  served  with  facility  is  five — one  gunner  and  four  can- 
noneers. 

In  this  case  Nos.  5  and  6  are  dispensed  with,  and  the  piece  is 
run  to  and  from  battery  as  explained  for  the  siege  howitzer. 
.{Pars.  264  and  268.) 

With  four  7ne7i—-one  gunner  and  three  cannoneers — Nos.  1,  2, 
and  3.  in  running  the  piece  to  and  from  battery,  perform  duties 
as  before,  and  the  gunner  that  of  No.  4.  In  loading,  No.  2,  in 
addition  to  his  own  duties,  performs  those  of  No.  4. 

With  three  men — one  gunner  and  two  cannoneers — Nos.  1,  2, 
and  the  gunner  perform  duties  as  above.  In  loading,  No.  1  per- 
forms the  duties  of  No.  3  as  well  as  his  own.  No.  2  performs 
those  of  No.  4,  as  in  the  preceding  case. 

When  No.  2  serves  ammunition,  he  goes  for  the  cartridge, 
and  places  the  pass-box  behind  his  post  before  assisting  No.  1 
to  sponge. 

252.  In  all  firings,  when  a  primer  fails,  the  gunner,  after 
waiting  a  few  moments  to  see  that  the  piece  is  not  hanging  lire, 
steps  in  front  of  the  left  wheel  and,  reaching  over,  pricks;  No. 
3,  reaching  over  the  right  wheel,  gives  him  a  fresh  primer  to 
which  he  has  hooked  his  lanyard. 

253.  Sponge  and  rammer  staves  are  marked  with  a  white 
ring  painted  around  them,  to  show — with  the  sponge,  when  it 
is  at  the  bottom  of  the  bore;  with  the  rammer,  wheu  the  pro- 
jectile is  home.     This  rule  is  generaL 

254.  Rifle  projectiles  are  always  to  be  lubricated  previous 
to  loading;  they  are  then  easily  pushed  home,  and  their  range 
iind  accuracy  of  flight  increased.     This  rule  is  general. 

Organization  of  Siege  Guns  into  Batteries  fob 

Field  Service. 

255*  It  has  been  found  from  actual  experience  that  the 
4.5-inch  siege  gun  is  capable  of  accompanying  an  army  in  the 


ORGANIZATION    OF   SIEGE   GUN    BATTERY.  1KJ 

field  with  almost  the  same  facility  as  the  12-pouuder.  Its  great 
range,  power,  and  accuracy  endow  it  with  many  advantages 
when  used  as  a  heavy  field-piece,  and  it  should  form  a  portion 
of  the  artillery  of  every  army  organized  for  campaign  purposes. 

For  this  service  the  pieces  are  organized  into  batteries  of  four 
or  six  guns  each,  and  equipped  after  the  manner  of  light  field 
batteries. 

Each  piece  is  furnished  with  two  caissons  of  the  usual  pattern, 
having,  however,  only  two  partitions  in  each  half-chest ;  these 
are  parallel  to  and  4.5  inches  from  each  side — the  outer  spaces 
for  projectiles,  the  inner  for  cartridges.  This  arrangement 
allows  16  rounds  for  each  chest,  48  per  caisson  and  96  per  gun. 
A  tray  in  each  chest  serves  to  carry  pouches,  primers,  and  fuses. 
One  spare  wheel  is  carried  for  the  caissons  of  each  two  pieces. 
Caissons  not  carrying  spare  wheels,  carry  picket- ropes  and 
forage.  The  picket-rope  should  be  in  sections;  each  section 
long  enough  to  accommodate  the  horses  of  oik*  piece  and  its  two 
caissons,  together  with  a  proportional  share  of  spare  and  other 
horses.  This  requires  each  section  to  he  35  yards  long.  The 
un&s  of  the  ropes  should  be  provided  with  hooks ;  these,  besides 
Miauling  them  to  be  used  more  conveniently  as  picket-ropes, 
allow  of  their  being  used  as  drag-ropes  for  extricating  carriages 
from  difficult  places  on  the  march. 

Light-artillery  harness  is  used,  but,  owing  to  the  weight  of  the 
pole,  breast-hooks  of  extra  strength  are  provided  for  the  wheel- 
horses.  The  swing  team  being  attached  to  lead-bars,  wheel- 
traces  are  required  for  it. 

The  implements  for  the  piece  are  as  follows : 

250*  Six  handspikes;  small  ends  under  sweop-bar,  resting 
on  axle,  large  ends  resting  on  splinter-bar,  and  secured  by  a 
leather  strap  passing  from  the  hounds,  through  loops  on  the 
handspikes,  to  buckles  on  the  fork;  or  by  a  rope  passed  through 
lings  on  the  handspikes  and  around  through  staples  on  the 
hounds  and  fork. 

One  short  roller ;  on  the  stock  between  the  lunette  bolts; 
secured  by  a  rope  passing  through  a  hole  in  the  axis  of  the  roller 
and  fastened  to  the  stock. 

One  trace-rope;  two  half-hitches  in  the  middle  around  the 
cascable ;  ends  turned  around  the  maneuvering  bolts,  and  cross- 

2;  to  take  up  the  slack.  This  secures  the  piece  from  sliding  on 
carriage. 

The  sponge  and  rammer  heads  are  upon  the  same  staff,  which 

Mit  to  the  shortest  practicable  length.   Two  sponges  and  ram- 

•rs  are  allowed  to  each  piece,  and,  together  with  one  worm  for 
h  two  pieces,  are  carried  upon  the  sides  of  the  piece,  secured 


94  ORGANIZATION    Ofr    SIEGE    GUN    BATTERY. 

by  two  stout  leather  straps  buckled  around  the  chase  and  the 
body  of  the  gun. 

The  service  of  the  piece,  so  far  as  sponging  and  ramming  are 
•concerned,  is  similar  to  that  for  light  field-pieces. 

The  sponge-bucket  is  carried  in  the  same  manner  as  for  light 
field-pieces.  One  fuse- wrench,  one  fuse-gauge,  one  fuse-knife, 
one  fuse-reamer,  and  one  pair  of  gunner's  pincers  for  eacli  piece 
are  carried  in  the  trays  of  the  limber  chests  of  the  caisson. 

A  cartridge-pouch  is  used  instead  of  pass-box,  and  is  carried 
by  No.  4  suspended  from  the  left  shoulder  to  the  right  side. 

Large  and  heavy  horses,  particularly  for  wheel-teams,  are 
selected  for  the  guns.  Except  where  the  roads  are  unusually 
good,  ten  are  allowed  to  each  piece.  Each  horse,  both  for  piece 
iii id  caissons,  is  provided  with  a  nose-bag,  carried  as  for  a  light 
field  battery,  and  one  watering-bucket  is  allowed  for  each  pair 
-of  horses,  carried — those  for  the  pieces  on  hooks  attached  to  the 
rear  axle  ;  those  for  caissons  as  in  light  artillery. 

One  lifting-jack  for  each  two  pieces  is  carried  on  one  of  the 
•caissons  belonging  to  these  pieces.  The  lifting-jack  weighs  160 
pounds,  and  is  carried  on  a  caisson  having  no  spare  wheel. 

Each  caisson  is  supplied  with  axes,  shovels,  picks,  pan  lines. 
-<fcc,  as  for  a  light  field  battery. 

Two  hundred  rounds  of  ammunition  are  allowed  for  each  piece ; 
that  not  contained  in  the  caissons  is  carried  in  transportation- 
wagons. 

One  spare  gun  carriage,  with  limber  complete,  drawn  by  six: 
horses,  accompanies  each  battery. 

Three  spare  poles  for  the  limber  of  the  piece,  ironed  and  fitted 
ready  for  insertion,  are  carried  on  the  spare  carriage. 

Each  battery  is  furnished  with  a  battery-wagon  and  forge. 
These  contain  supplies  as  hereinafter  prescribed. 

The  spare  carriage,  battery-wagon,  forge,  ammunition,  and 
baggage-wagons  form  a  train,  and,  on  the  march,  usually  accom- 
pany the  light-artillery  train. 

The  cannoueers  carry  their  equipments  and  march  by  the  side 
of  the  piece,  as  in  a  light  field  battery. 

In  place  of  the  shoe  (which  is  entirely  useless)  a  stout  rope, 
attached  to  the  ring-bolt  of  the  lock-chain,  is  substituted.  This 
rope,  passed  around  the  felly  with  two  or  three  turns,  is  held  by 
n  cannoneer  walking  by  the  side  of  the  piece.  In  this  manner 
ho  is  enabled  to  let  the  wheel  go  as  it  approaches  the  bottom  of 
a  descent. 


ORGANIZATION   OF   SIEGE  GUN   BATTERY. 


95 


Composition  of  a  siege  battery  of  six  pieces  organized  and 
equipped  for  campaign  service. 


••••»•••« 


Captains.. |      1 

I  Lieutenants {      4    :...... 

Sergeants ; 9 

Corporals ' '  12 

|  Artificers \ i  6 

I  Trumpeters ,  2 

,  G-uidon :  1 

'  Drivers I '  75 

Cannoneers ,  78 

Spare  horses 


Total. 


183 


6 

2 

1 

150 


C  Including  first-sergeant, 
<  quartermaster,  stable, 
(  and  veterin'y  sergeants. 
$  3  blacksmiths,  2  saddlers, 
(   1  wheelwright. 


18 


191 


\ 


For  6  pieces,  12  caissons,  1 
spare  carriage.  1  battery 
wagon,  and  1  forge. 


251.  On  dry  and  firm  ground  the  siege  gun  may  be  fired  as 
an  ordinary  field-piece ;  under  all  other  circumstances  it  requires 
a  platform.  When  time  permits,  a  good  platform  may  be  im- 
provised from  material  found  in  the  vicinity;  but  to  provide 
against  every  emergency,  a  platform  for  each  piece  should  be 
carried  with  the  battery,  or  at  least  with  the  train,  when  easily 
accessible. 

The  platform  is  the  one  described  in  par.  226.  These  are 
carried  in  transportation-wagons,  each  wagon  carrying  three 
platforms. 

The  supply  of  projectiles  should  be  about  equally  divided  be- 
tween solid  shot,  time,  and  percussion  shells;  i.  e.,  one-third 
solid  shot,  one-third  time-fuse  shells,  and  the  remaining  third 
percussion  shells.  It  is  unnecessary  to  have  either  case-shot  or 
canister. 

Each  piece  is  provided  with  a  field-glass  and  telemeter. 


96 


ORGANIZATION    OF   SIEGE   GUN   BATTERY. 


258.  The  following  are  the  supplies  carried  in  the  battery- 
wagon  and  forge  for  a  battery  of  six  guns  : 

Forge  A. 


Contents  op  Limber-chest. 
(Smith's  tools  and  stores.) 


Horseshoes,  Nos.  2  and  3 lbs- 
Horseshoes.  Nos.  2  and  3 lbs.. 

Horseshoe  hails,  Nos.  2  and  3.. lbs.. 

Washers  and  nuts,  No.  2 

Washers  and  nuts,  No.  3 ... 

Washers  and  nuts,  No.  4 

Nails,  No.  1,  C lbs.. 

Nails,  No.  2,  C lbs.. 

Tire-bolts 

Keys  for  ammunition  chests 

Linch-washers  (caisson) 

Ljinch-pins  (caisson) 

Linch-pins  (for  piece) 

Chains,  Nos.  1  and  2 feet.. 

Cold-shut  Slinks,  No.  3 

Cold-shut  Slinks,  No.  5 

Hand  cold-chisels 

Hardie 

Files,  assorted,  with  handles 

Buttress 

Hand-punches,  round  and  square... 

Screw-wrench 

Hand  screw-driver ~ 

Hand  vise 

Smith's  calipers,  pair 

IWs,  pairs:  }  Nos.  1,2,  3,  and  4 

Wood  screws,  1  in.,  No.  14.. ..gross.. 

Q,uart  can  of  sperm  oil 

Borax lbs- 
Fire-shovel 

Poker 

Split  broom 

Hand-hammers 

JEtiveting-hanimer 

Nailing-hammer 

Sledge-hammer 

Chisels  for  hot  iron 

Chisels  for  cold  iron 

Smith's  tongs 

Fore-punch 

Creaser 

Fuller 

Nail-claw 

Round-punch 

Tap- wrench 

Die-stock 

Nave-bands,  developed 

Tire-bands,  developed 


No. 


100 

100 

50 

30 

10 

4 

1 

1 

10 

5 

8 

12 

6 

2 

50 
12 
2 
1 
12 
1 
2 
1 
1 
1 
1 
4 
4 
1 
1 
2 
1 
1 
1 
2 
1 
1 
1 
2 
2 
3 
1 
1 
1 
1 
1 
1 
1 
4 
2 


100.00 
100.00 
50.00 
5.25 
3.20 
2.15 
1.00 
1.00 
5.00 
1.80 
7.30 
8.37 

1.54 
2.50 
2.00 
2.00 
0.75 
10.00 
1.50 
2.00 
2.42 
0.32 
1.00 
0.40 
1.50 
1.83 
2.10 
2.70 

3.05 
1.90 
1.25 
6.50 
1.05 
1.80 

10.50 
3.00 
3.00 

15.00 
1.00 
1.00 
2.40 
5.00 
2.10 
3.75 
6.25 

11.75 
2.75 


Box  A  1. 
Box  A  3. 
Box  A  2,  large  divis- 
ion. 


-In  box  A  2,  91.11  lbs. 


In  box  A  4, 28.52  lbs. 


-  In  box  A  5, 80.05  lbs. 


■  In  Box  A  5, 80.05  lbs. 


OBGANIZATION    OF   SIEGE   GUN    BATTERY. 


97 


Forge  A. — (continued.) 


Contents  op  1<imbkr-chest. 
(Smith's  tools  and  store?.) 


Shoeing-hammer . 

Pincers,  pair 

Rasps  (12  inches). 

Shoeing-knife 

Toe-knife 

Pritchel 

Nail-punch 

Clinching-pin 

Oil-stone 

Leather  aprons... 
Horse-tail  brash... 


Iron  square. 


Padlock 

Tar-bucket 

Boxes 

Tow  for  packing. 


No. 


1 

1 
2 
1 
1 
1 
1 
2 
1 
2 
1 


1 
1 
6 


Total. 


•mm 

I 


.0.82 
2.00 
2.15 
0.33 
0.3Q 
0.85 
0.80 
1.00 
1.C0 
3*00 
1.00 

2.00 

0.50 

7.00 

53.45 

5.00 

484.38 


Place. 


•  In  shoeing-box,  12.75  . 

lbs.  ■ 


Fastened  on  lnsido 
of  the  chest-cover 
with  two  copper 
clamps. 

On  the  chest. 

On  its  hook. 


One  pound  of  horseshoe  nails,  No.  3,  contains  140  nails;  one 
pound  of  horseshoe  nails,  No.  2,  contains  112  nails;  one  hun- 
dred pounds  of  horseshoes,  contain  90  shoes. 

Contents  of  forge-body. 


Tools  and  Stores. 


Square  iron,  24  in.  and  1  in 

Flat  iron,  1H  in.  x  %,  1  in.  x  &,  IH 

in.  x  1H  x  H  in 

Round  iron,  %  in 

Cast-steel,  %  in.  square 

English  blistered-steel 


No. 


Boxes  5  and  6,  containing 

Horseshoes,  Nos.  2  and  3 

Horseshoe  nails,  Nos.  2  and  3.. 

Water-bucket 

Watering-bucket  (leather 

Anvil.., 

Vise 

Bituminous  coal 

Coal-shovel 

Padlock 

Tow 


1 
1 
1 
1 


1 
1 


Total. 


Weig't. 
Lbs. 


100 

50 

50 

10 

5 


200 

20 

10 

8 

100 

20 

250 

5 


5 
842 


Place. 


In  the  iron-room. 
Bars  not  more  than 
3  feet  long.  Square 
iron   in   two  bun- 
dles. 


In  iron-room. 

On  its  hook. 
On  the  vise. 
On  the  fireplace. 
On  stock  of  forge. 

In  the  coal-box. 

On  coal-box. 


L_. 


98 


ORGANIZATION   OF   SIEGE   GUN    BATTERY. 


1.  Anvil-block,  carried  on  the  hearth  of  the  forge,  and  secured 
by  having  a  hole  through  its  axis,  through  which  is  passed  a 
lashing-rope. 

Contents  of  Umber-chest,  Battery-wagon  C. 


Tools  and  Stores. 


Carriage-maker's  tools  : 


Hand-saw - 

Tenon-saw  (14  in.) 

Jack-plane 

Smoo  thing-plane 

Brace,  with  24  bits 

Spokeshave 

Gfauge 

Plane-irons 

Saw-set 

Rule  (2  feet) 

Gimlets 

Compasses,  pair 

Chalk-line 

Brad-awls 

Scriber 

Saw-flies  (4H  in.) 

Wood-files  (10  in.) 

Wood-rasp  (10  in.) 

Trying-square  (8  in.) 

Hand  screw-driver 

Oil-stone 

Broad-axe 

Hand-axe 

Claw-hatchet 

Claw-hammer 

Pincers  (small),  pair 

Table  vise 

Framing-chisels  (1  in.  and  2  in.).... 
Firmer-chisels  (?£  in.  and  VA  in.)... 
Framing-gouges  (1  in.  and  1H  in.).. 
Angers  and  handles  (3$  in.,  %  in., 

?£  in.,  1  in.,  2  in.) 

Screw-wrench 

Folling-axe..  ? 

Adze $ 

Framo-saw 

Quart  can  of  sperm  oil 

( Jompass-saw 

Tacks  (carpenters'),  M 

Measuring-tape 

Chalk 


with  handles. 


No. 


12 


12 


2 
2 


{ 


5 
1 


I 

is 


Lbs. 

4.00 
1.50 
4.15 
1.80 
4.35 
0.30 
0.30 
1.05 
0.25 
0.14 
0.95 
0.18 
0.10 
0.17 
0.15 
0.87 
1.12 
0.40 
0.60 
0.:$2 
1.50 
6.00 
5.00 
2.00 
1.50 
1.06 
3.80 
3.00 
1.00 
2.60 

4.50 
2.42 
6.00 
3.30 
4.50 
2.70 


5.00 
2 .00 


Place. 


I  Fastened  to  the  in- 
>    side  of  chest  cover. 


■In  box  O  1,17.20  lbs. 


►In  box  O  2,32.23  lbs. 


-In  box  C  3,23.25  lbs. 


1 


ORGANIZATION   OF  SIEGE  GUN   BATTERY. 


99 


Contents  of  limber-chesty  Battery-wagon  (7.— (continued.) 


Tools  and  Stores. 


Saddler' 8  tools  and  stores. 


Mallet  — ._ 

Olam 

Hammer 

Shoe-knives 

Half-round  knife 

Shears,  pair : 

Sandstones , 

Rule  (2  feet) 

Needles,  assorted 

Collar-needles 

Thimbles 

Awls ■ 

Awl-handles 

Punches,  assorted 

Pincers,  pairs 

Pliers,  pairs 

Claw-tools 

Creasers 

Gauge-knife 

Scissors,  pair 

Compass,  pair 

Strap-awls 

Saddler's  mallet 

Saddler's  clam 

Bristles 

Saddler's  thread 

Bees-wax 

Black-wax 

Patent  thread 

Shoe  thread lbs- 
Buckles,  assorted  (0.75  in.  to  1.5 

in ) .doz... 

Tacks  (iron  and  copper),  assorted. 

Hand-saws 

Tenon-saws 

Blades  for  frame-saws 


i 


Total. 


No. 


1 
1 
1 
2 
1 
1 
2 
1 

100 
5 
4 

86 
6 
6 
8 
6 
2 
1 
1 
1 
1 
3 
1 
1 


2 
2 
4 


* 


Lbs. 

1.75 
5.00 
0.65 
0.20 
0.28 
0.47 
0.30 


0.50 
0.75 
1.00 
6.75 


0.75 


0.25 


1.75 
5.00 
2.00 
2.00 
3.00 
5.00 
5.00 
2.00 


1. 00 

10.00 

2-00 


173.00 


Place. 


-In  box  04. 


100 


ORGANIZATION   OF   SIEGE   GUN   BATTERY. 


Contents  of  wagon-body. 


Tools  and  Stores. 


Grindstone,  14-in.  x  4  in... 
Arbor  and  crank  for  do.... 

Pintles  (for  piece) 

Horse-collars  (assorted) 

Grirths 

Lead-traces 

Whips  (artillery) 

Wheel-traces 

Currycombs 

Horse-brushos 

Nosebags 

Saddle-blankets 

Spurs  and  straps pairs.. 

Halters  and  straps 

Watering-bridles 

Bridles  (artillery) 

Hame-straps 

Harness-leather sides... 

Bridle-leather sides... 

Sash-cord pieces... 

Pole-yoke 

Elevating  screw 

Saw,  cross-cut  (6  feet) 

Rope-trace,  feet...  *"  "  ' 
Block  (treble)  for 

above 

Block  (double)  for 

above 

Watering-buckets 


Js§f 


No. 


1 
1 
1 

10 

20 

15 

5 

10 
15 
15 
10 
20 
5 

20 

10 

6 

40 

2 

3 

6 

1 

1 

1 

200 


1 
5 


•fa 

■a 


Lbs. 

60 

35 
45 
12 
75 

2 
48 
12 
12 
11 
60 

5 

65 
12 
18 

8 

50 
33 
10 
13 
32 
12 


40 


Tools  and  Stores. 


Fuse-wrenches 

Fuse-gauges 

Fuse-knives 

Fuse-reamers 

Gunner's  pincers 

Vent-punches 

Breech  sights 

Priming- wires 

Gunner's  gimlets 

Primer-pouches 

Castile-soap 

Handspikes 

Tallow 

Staves — sponge  and  ram- 
mer (lashed  to  body  of 

wagon  outside) 

*Ncat's-foot  oil ('?al. 

♦Grease,  wheel  (l-fl>  cans). 

Nails,  (4,  6, 8,  and  10-pen- 

„  ny) 

Claw-hatchet 

Spirit-level  (carpenter's). 

Sperm  or  wax  candles 

Rammer-heads , 

Sponge-heads , 

Sponges , 

Sponge-covers 

Lanyards    for    friction- 
primers 

Dark  lanterns 

Common  lanterns 


Total. 


No. 


3 
3 
3 
3 
3 
3 
3 
12 
6 
3 


3 
6 


6 

3 

12 


6 
3 
4 


bo 

*-* 
<x> 

is 


Lbs. 


SO 

o 

.0 


10 
36 
30 


11 
50 
70 

20 

2 


5 
5    : 

5     , 
3 


3 
4.60 


11C0 


*InBox0  5. 

• 

The  battery- wagon  here  mentioned  is  that  furnisher!  from  the 
arsenals;  but,  being  cumbersome  and  quite  unsuitable  for  field 
service,  it  is  better  to  utilize  its  body  and  limber-chest  by  plac- 
ing them  on  the  running  gear  of  the  army  transportation-wagon . 
The  limber-chest  can  be  attached  to  the  front  part  of  the  wagon- 
body  by  strong  iron  brackets,  and  serves  as  a  seat  for  the  driver. 
A  similar  chest  can  be  placed,  in  like  manner,  on  the  rear  end 
in  place  of  the  forage-rack.  In  the  front  chest  is  carried  the 
carriage-maker's  outfit,  and  in  the  rear  one  that  of  the  saddler. 

On  the  middle  of  each  side  of  the  body  may  be  attached  a 


ORGANIZATION   OF   SIEGE   GUN   BATTERY.  101 

small  chest  for  horse  medicines,  or  such  other  small  articles  as 
may  be  required  of  easy  access. 

When  the  wagon  is  thus  arranged  it  is  as  easily  drawn  by  four 
horses  as  the  other  by  six,  and  one  driver,  using  double  lines,  is 
sufficient. 

The  arrangement  for  attaching  the  draught-horses  to  siege- 
gun  carriages  being  similar  to  that  for  the  army  transportation- 
wagon,  the  harness  used  with  the  latter  will  answer  for  the  for- 
mer. A  driver  is  required  for  each  pair  of  horses,  as  in  light  field 
artillery. 

The  officers,  first-sergeant,  and  chiefs -of- detachment  are 
mounted  and  equipped  as  for  light  artillery. 

When  in  the  presence  of  the  enemy,  the  am  munition- wagons 
an*  kept  out  of  range  of  his  fire,  but  always  near  enough  to  be 
easily  reached  by  the  caissons  for  replenishing  ammunition 
chests. 

The  battery  should  be  repainted  once  a  year,  usually  in  the 
spring.  To  do  this,  a  battery  complete,  of  six  pieces,  requires  : 
120  lbs.  olive  paint;  15  lbs.  black  paint;  10  galls,  linseed  oil;  3 
galls,  spirits  turpentine;  12  paint  brushes  (assorted). 

Harness,  when  exposed  constantly  to  the  weather,  should  be 
oiled  once  in  four  months,  requiring  each  time  6  gallons  neat's- 
foot  oil  and  30  lbs.  tallow. 

The  tallow  is  melted  and  mixed  with  the  oil.  The  harness 
should  be  well  soaked  and  washed,  and  the  mixture  appjied 
warm  and  thoroughly  rubbed  in  while  the  leather  is  still  damp. 

259*  The  following  list  contains  a  fair  supply  of  horse  medi- 
cines for  a  battery  of  six  pieces  : 


Assafetida 2  pounds. 

Aloes 2  pounds. 

Adhesive  plaster 1  yard. 

Aqua  ammonia 1  quart. 

Alum 1  pound. 

Bluestone 1  pound. 

Borax 1  pound. 


Mustang  liniment 6  bottles. 

Nitre 1  pound. 

Olive  oil 2  quarts. 

Opodeldoc 6  bottles. 

Rosin 1  pound. 

Spirits  turpentine 2  quarts. 

Spirits  nitre 1  quart. 


British  oil 12  bottles.  ,  Flour  of  sulphur y>  pound. 

Blister  liquid %  quart.        Suerar  of  lead 2  pounds. 

Calomel %  pound.    I  Tartar  emetic "hi  pound. 

Condition  powders 2  pounds.  ]  Tar t..  l  quart. 

Cerate,  simple 2  pounds.     Whisky 2  gallons. 

Glauber  salts 10  pounds.     Farrier's  needles 4 


flax-seed,  ground 8  pounds. 

Laudanum 1  quart. 

-ard 5  pounds. 

junar  caustic H  ounce. 

lercurial  ointment 1  pound. 


Farrier's  scissors 1 

Horse-fleam 1 

Lancet 1 

Syringe 1 


These  should  be  put  tip,  as  far  as  practicable,  in  metallic  cans 
id  in  strong  bottles.    When  the  battery-wagon  is  arranged  as 


102 


SIEGE   HOWITZER — SERVICE. 


before  described,  they  will  be  packed  and  carried  in  the  boxes 
attached  to  the  sides  of  the  body;  otherwise  they  will  be  carried 
In  boxes  inside  of  the  body. 

Quartermaster's  Stores. 

260.  In  addition  to  the  wagons,  horses,  harness,  <fcc,  here- 
tofore mentioned,  there  will  be  required  for  the  battery  the  fol- 
lowing : 

3  wall  tents. 

3  wall-tent  flies. 

3  sets  wall-tent  poles  and  pins. 
75  shelter  tents  (double). 
10  camp-kettles. 
10  mess-pans. 

2  trumpets,  cords  and  tassels. 

1  company  clothing-book. 

1  company  order-book. 

1  company  descriptive-book. 

1  company  morning  report-book. 

These  articles,  excepting  the  trumpets,  are  carried  in  a  trans- 
portation-wagon ;  the  same  wagon  will,  in  addition,  carry  two 
days'  full  rations  for  the  men  of  the  battery. 
The  forage  is  carried  in  transportation-wagons. 

•  Service  of  Siege  Howitzer. 

{Plate  12.) 
Description  of  Piece. 

261.  Howitzer,  cast-iron ;  smooth-bore ;  muzzle-loader. 

Number^  weights^  and  dimensions. 


Designation. 


Calibre ....... 

Weight..^ 

Length 

Diameter  (maximum) 

Diameter  (minimum)  

Length  of  bore  (calibres.) 

Windage 

Charge  (cannon  powder) 

Shell  (empty) 

Preponderance 

Weight  of  piece,  carriage,  limher,  and  imple'ts.. 
Horses  to  transport 


No. 


5.81 


8. 


SIEGE   HOWITZER — SERVICE. 


103 


Kanges  in  yards. 


Elevatiow. 


Degrees. 

1 

2 

3 

4 

5 
12.5 
15 


Shell. 
Lbs. 

Range. 

Yds. 

45 

435 

45 

618 

45 

720 

45 

992 

45 

1150 

45 

2280 

45 

2300 

Ton  op 
Flight. 


Seconds. 
1.33 

**    • 

3. 

4. 
5. 


Bursting  charge  of  shell.  1  lb. ;  charge  to  blow  out  fuse-plug, 
4oz. 

The  howitzer  on  its  platform  admits  of  13  degrees  elevation 
and  10  degrees  depression. 

In  works,  it  is  fired  from  a  wooden  platform ;  or  when  the 
ground  is  level  and  firm,  it  may  be  fired  without.  It  is  used 
chiefly  in  field  works  for  flank  defense. 

To  serve  the  piece. 

262.   Six  men  are  required:  one  chief-of -detachment,  one 
gunner,  and  four  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 

Two  on  each  side  of  piece;  leaning 
against  parapet,  in  line  with  can- 
noneers. 

One  yard  behind,  and  parallel  to 
the  cannoneers  of  the  right;  sup- 
ported on  a  prop,  head  towards 
the  parapet. 

Cartridge-pouch Suspended  from  cascable. 

PrimPr-TintiPh  I  Containing  friction  primers  and  lan- 

rnmei  poucn j      yar(1 .  BUspendod  from  cascable. 

*»-*  p°»ch }  o^*c£Ssrr,n,;  suspeud" 

Mit  noueh  \  Containing  breech  sight;  suspended 

0  i-pouc    j      from  cascable. 

rhpol  nlinokr  \  0ne  on  each  sklc  °*  the  P'iece»  ncar 

nect  cnocko j      the  en(1  of  the  hnpter# 


Bandspikes 


Sponge.. 
Rammer. 


} 


In  a  basket  or  on  a  shelf,  against  the 
parapet,  near  No.  2. 


In  filling-room  of  service  magazine. 


104  SIEGE    HOWITZEll — SERVICE. 

Vent-cover Covering  the  vent. 

Tompion  In  the  muzzle. 

-o  \  Leaning  against  the  parapet,  near 

•Broom |      No.  2. 

•o    ,      K       !  \  Containing  cartridges;  at  a  safe  and 

jsuage-oarrei J      convenient  place  near  the  piece. 

Pair  of  sleeves 

Shell-hooks 

Plummet 

Splints 

Sponge-bucket Near  sponge  and  rammer. 

Grummet-wad On  end  of  hurter,  near  No.  2. 

Fuse-gauge  

Fuse-knife , 

Fuse-wrench... 
Fuse-reamer  ... 
One  lanyard  (extra) J 

To  each  two  pieces  there  should  be 

One  worm 

One  liamrae r-w re n ch . . . . 
One  gunner's  quadrant. 

One  vent-punch 

One  vent-gimlet. 
One  gunner's  level .... 
One  gunner's  pincers. 

If  the  piece  is  without  elevating  screw,  a  wooden  quoin  is  nec- 
essary, and  this  is  under  the  breech. 

For  the  purpose  of  instruction,  a  cartridge-bag  filled  with  saw- 
dust, and  a  priming-wire  bent  into  a  hook,  for  withdrawing  it, 
are  provided,  and  are  in  the  basket. 

When  there  is  no  parapet  the  handspikes  are  placed,  three  on 
each  side,  standing  between  the  cheeks  and  wheels  of  the  car- 
riage, in  front  of  and  resting  against  the  axle-tree. 

The  projectiles  are  in  the  filling-room  of  the  service  magazine ; 
the  fuses,  cartridges,  and  primers  are  in  the  service  magazine. 

To  distribute  the  equipments. 

263.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  steps  to  the  breech;  takes  off  the  vent-cover, 
handing  it  to  No.  2  to  place  against  the  parapet,  outside  of  his 


>  •  ■■•  ••  •  •  •  •  i 


In  filling-room  of  service  magazine. 


SIEGE   HOWITZER — SERVICE.  10") 

post;  gives  the  primer-pouch  to  No.  3,  and  the  cartridge-pouch 
to  No.  4;  equips  himself  with  the  sight-pouch  and  his  own 
pouch;  clears  the  vent,  levels  the  piece,  and  resumes  his  post. 
No.  3  equips  himself  with  the  primer-pouch. 

No.  4,  after  equipping  himself  with  the  cartridge-pouch,  assists 
No.  2  to  put  on  the  sleeves. 

Nos.  1  and  2,  after  passing  a  handspike  each  to  Nos.  3  and  4. 
take  one  each,  for  himself.  The  handspikes  are  held  and  laid 
down  as  prescribed  in  pars.  235  and  236.  The  gunner  direct* 
No.  3  toembar  under  and  raise  the  breech  to  enable  him  to  level 
the  piece;  applies  hW  level  to  ascertain  the  highest  point  of 
metal  at  the  base,  which  he  marks  with  chalk.  In  case,  there  is 
no  sight  upon  the  muzzle,  he  does  the  same  at  the  latter  place, 
and  snaps  a  chalk-line  between  to  mark  the  line  of  metal. 

264.  The  service  of  the  piece  is  executed  as  follows:  The 
piece  being  in  battery,  the  instructor  commands: 

1.  From  battery. 

The  gunner  moves  two  yards  to  his  right;  Nos.  1,  2,  3,  and  4, 
all  facing  from  the  epaulment,  erabar;  Nos.  1  and  2  through  the 
rear  spokes  of  the  wheels,  near  the  felly,  under  and  perpendicu- 
lar to  the  cheeks  ;  Nos.  3  and  4  under  and  perpendicular  to  the 
manceuvering  bolts.  All  being  ready,  the  gunner  commands: 
Heave,  which  is  repeated  as  often  as  may  be  neces>ary.  He 
sees  that  Nos.  3  and  4  guide  the  trail  in  prolongation  of  the  direc- 
trix of  the  embrasure,  and  as  soon  as  the  wheels  are  about  one 
yard  from  the  parapet  commands:  Halt.  If  the  platform  has 
an  inclination,  Nos.  1  and  2  chock  the  wheels  in  front.  All  re- 
sume their  posts. 

1.  By  the  numbers*  2.  Load. 

265.  Nos.  1,  2,  and  4  lay  down  their  handspikes;  No.  2  takes 
out  the  tompion  and  places  it  near  the  vent-cover,  and  resumes 
his  post ;  No.  1  faces  to  his  right,  and  seizes  the  sponge-staif  at  its 
middle  with  the  right  hand,  back  up ;  places  himself  at  the  muz- 
zle, forces  the  sponge  to  the  bottom  of  the  bore,  and  grasps  the 
staff  with  both  hands,  the  hack  of  the  right  up  and  that  of  the 
left  down. 

No.  3,  facing  towards  the  parapet,  embars  under  the  breech 
>r  knob  of  the  cascable,  and  assists  the  gunner  in  adjusting  the 
nece  conveniently  for  loading. 

No.  4  goes  for  a  cartridge  and  shell ;  puts  the  cartridge  in  his 
ouch;  takes  the  shell  in  both  hands;  returns  and  places  it  on 
le  grummet-wad,  and  stands,  facing  the  piece,  about  eighteen 
nclies  to  the  rear  and  left  of  No.  2. 


106  SIEGE   HOWITZER — SERVICE. 

The  gunner  places  himself  near  the  stock,  as  in  par,  238,  and 
closes  the  vent;  adjusts  the  piece  to  about  one  degree  elevation, 
and  makes  a  signal  for  No.  3  to  unbar. 

1.  Sponge. 

266.  No.  1,  pressing  the  sponge  firmly  against  the  bottom  of 
the  bore,  turns  it  three  times  from  right  to  left,  and  three  times 
from  left  to  right;  draws  it  out,  turns  the  sponge-head  over  to- 
wards the  front,  and  places  the  rammer-head  against  the  right 
side  of  the  face  of  the  piece,  holding  the  staff  in  both  hands,  the 
back  of  tiie  right  down  and  that  of  the  left  up;  as  soon  as  the 
cartridge  is  inserted,  he  enters  the  rammer  and  pushes  the  car- 
tridge home. 

No.  4  gives  the  cartridge  to  No.  2,  who,  having  placed  him- 
self between  the  wheel  and  piece,  inserts  it  into  the  muzzle. 
As  soon  as  No.  4  lias  given  the  cartridge  to  No.  2,  he  takes  the 
shell-hooks  and  engages  them  in  the  ears  of  the  shell  in  readi- 
ness for  No.  2,  who,  making  a  face  and  a  half  to  his  left,  takes 
hold  of  the  shell-hooks,  raises  the  shell  and,  making  a  face  and 
a  half  to  his  right,  stands  in  readiness  to  insert  it  into  the  bore 
as  soon  as  No.  1  has  pushed  home  the  cartridge. 

T.  Ram. 

26*7.  No.  1  sets  the  cartridge  home  by  pressing  firmly  upon 
it;  throws  out  the  rammer,  replaces  it  on  the  prop,  and  re- 
sumes his  post. 

No.  2  introduces  the  shell  into  the  bore,  keeping  the  arms  of 
the  shell-hook  in  a  vertical  plane,  and  sets  the  shell  carefully 
against  the  cartridge,  taking  cure  that  the  fuse  is  in  the  axis  of 
the  piece.     Canister  is  shoved  home  by  hand. 

Double  charges  of  canister  may  be  fired. 

If  the  piece  is  to  be  fired  horizontally,  or  at  an  angle  of  de- 
pression, No.  4  hands  a  splint  to  No.  2,  who  presses  it  under  the 
shell ;  replaces  the  tongs  and,  if  necessary,  sweeps  his  side  of 
the  platform ;  passes  the  broom  to  No.  1,  and  resumes  his  post. 

No.  1  sweeps  his  side  of  the  platform,  passes  the  broom  back 
to  No.  2,  and  resumes  his  post. 

No.  4,  after  passing  the  shell  to  No.  2,  resumes  his  post. 

The  gunner  pricks,  leaves  the  priming-wire  in  the  vent,  and, 
resuming  his  post,  adjusts  the  breech  sight  to  the  distance. 

1.  In  battery. 

26§.  Nos.  1  and  2  unchock  the  wheels,  and  Nos.  3  and  4, 
all  facing  towards  the  epaulment,  embar;  Nos.  1  and  2  through 
the  front  spokes  of  the  wheels,  near  the  felly,  under  and  perpen- 


SIEGE   HOWITZER — SERVICE.  107 

dicular  to  the  cheeks ;  Nos.  3  and  4  under  and  perpendicular  to 
the  stock,  guiding  the  muzzle  of  the  piece  into  the  middle  of  the 
embrasure.  The  gunner  commands:  Heave,  and,  as  soon  a& 
the  wheels  touch  the  hurter,  Halt,  when  all  unbar  and  resume 
their  posts. 

1.  Aim. 

269.  No.  3  lays  down  his  handspike  and  prepares  a  primer. 
Nos.  1  and  4,  facing  towards  the  parapet,  embar  under  and 

perpendicular  to  the  stock,  near  the  manceuvering  bolts;  No.  2, 
facing  in  the  same  direction,  embars  under  the  breech  or  knob 
of  the  cascable. 

The  gunner,  placing  himself  at  the  stock,  as  at  the  command 
load,  withdraws  the  priming- wire,  places  the  centre  point  of  the 
breech  sight  accurately  upon  the  chalk-mark  on  the  breech,  and, 
sighting  through  it,  gives  the  direction.  Nos.  1  and  4  move  the 
trail  to  the  left  or  right  at  the  command  Left  or  Right  from 
the  gunner. 

The  moment  the  piece  is  correctly  aimed,  the  gunner  rNes,. 
and  commands :  Ready,  making  a  signal  with  both  hands,  at 
which  Nos.  1,  2,  and  4  unbar  and  resume  their  posts. 

The  gunner,  taking  with  him  the  breech  sight,  goes  to  a  good 
place  to  observe  the  effect  of  the  shot. 

At  the  command  Ready,  No.  3  inserts  the  primer  in  the  vent ; 
Nos.  1  and  2,  laying  down  their  handspikes,  take  each  a  chock 
in  the  hand  nearest  the  parapet,  and,  breaking  off  with  the  foot 
farthest  from  the  parapet,  stand  ready  to  chock  the  wheel  after 
the  recoil. 

The  breech  sight  at  present  used  with  the  howitzer  is  one  of 
obsolete  pattern. 

When  sights  similar  to  those;  used  for  siege  guns  are  supplied, 
the  method  of  aiming  will  be  the  same  as  for  the  gun. 

When  the  piece  is  masked,  by  an  epaulment,  from  the  object,, 
the  direction  is  given  as  explained  for  mortars.     (Par.  343.) 

1.  Number  one  (or  the  like),  2.  Fire. 

270.  Executed  as  in  par.  244. 

To  load  without  the  numbers,  and  to  fire. 

271.  Executed  as  in  par.  245. 

To  unload. 

272.  The  piece  having  been  run  from  battery,  the  instructor 
rects  No.  2  to  take  out  the  shell  and  cartridge,  No.  4  carrying 
lem  to  their  place  in  rear  of  the  piece ;  No.  3,  with  his  hand- 
tike,  raises  the  breech  until  the  shell  rolls  to  the  muzzle,  where 

is  caught  by  No.  2,  who  hands  it  to  No.  4. 


108 


10-INCH    GUN — SERVICE. 


To  load  and  fire  continuously, 

273.  Executed  as  in  par.  246. 

To  cease  firing. 

274.  Executed  as  in  par.  247. 

To  secure  piece  and  to  replace  equipments. 

Executed  as  in  pars.  249  and  250. 

The  howitzer  is  prepared  for  campaign  service  as  explained 
for  the  siege  gun,  with  such  modifications  as  readily  suggest 
themselves. 

275.  For  transportation,  the  shells  are  carried  uncharged. 
To  charge  them,  two  men  and  the  following  implements,  in  ad- 
dition, are  required,  viz.:  One  set  of  powder-measures,  one  fun- 
nel, one  fuse-mallct,  one  fuse-setter,  one  rasp,  two  grummet-wads^ 
two  wipers*  one  bridge-barrel,  together  with  a  supply  of  fuse- 
plugs  and  tow. 

The  fuse-plugs  are  of  wood,  and  the  tow  is  to  stop  the  fuse- 
holes  until  the  shells  are  to  be  taken  to  the  piece.  The  shells 
should  be  well  cleansed  on  the  outside  from  rust  and  dirt.  This 
is  done  at  the  filling-room  of  the  service  magazine. 

Note. — The  shells  for  the  howitzer  should  be  strapped  to  sa- 
bots, in  which  case  the  loading  would  be  greatly  facilitated. 

The  foregoing  exercise  is  for  ammunition  as  now  furnished. 

For  the  service  of  the  siege  howitzer,  when  used  as  a  mortar^ 
see  par.  45S. 

Service  of  a  10-inch  Smooth-bore  Gun  in  barbette. 

(Fig.  1,   Plate  8.) 

Description  of  Piece. 

276.  Gun,  cast-iron  ;  muzzle-loader. 

Number,  weights,  and  dimensions. 


Designation. 


Calibre..... 

Length  of  piece 

Maximum  diameter 

Minimum  di-.imeter 

Length  of  bore  (calibres). 

Windage 

Initial  velocity  (feet) 

Charge  (cannon  powder). 

Solid  shot 

Shell  (unfilled) 

Weight  of  piece , 

Preponderance 


No. 


Lbs. 


10.5 


1275. 


25 

128 

1C2 

15,000 


Inch. 


10. 
136.6 
=8. 
10.2 


0.13 


10-INCH    GUN — SERVICE. 


10'J 


Carriage,  wrought -iron;  front  pintle,  without  air-cylinders 
or  other  recoil  checks.  The  new-pattern  carriage  will  he  pro- 
vided with  pneumatic  buffers.  The  top  -  carriage  will  weigh 
2500  pounds,  and  the  chassis  3500  pounds. 

Ranges  in  yards. 


Elevation. 

Shot. 

Shell.|  Time. 

Charge. 

Booouds* 

1°  00" 

511 

504 

1.33 

(A 

1°  30" 

724 

708 

1.95 

»3 

2°  00" 

910 

8SG 

2.56 

~ 

2°  30" 

109.'i 

1048 

3.15 

c 

p. 

3°  00" 

1251 

1195 

7.71 

o 

3°  30" 

1401 

1330 

4.25 

4°  00" 

1539 

1455 

4.79 

2» 

5°  00" 

1793 

1680 

583 

"*'o5 

6°  00" 

2019 

1S79 

6.82 

7°  00" 

2255 

2057 

7.78 

8°  00" 

2414 

2217 

8.71 

CO 

9°  00" 

2587 

2363 

9.60 

** 

10°  00" 

2749 

2498 

10.46 

a 

15°  00" 

3429 

U5 

20°  00" 

3976 

i— i 

The  piece  admits  of  30  degrees  elevation  and  6  degrees  depres- 
sion.   Its  platform  is  a  permanent  portion  of  the  fortification. 

To  serve  the  piece. 

277.  Eight  men  are  necessary  :  one  chief-of-detachment,  one 
gunner,  and  six  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 


Truck  handspikes  (iron)...  }  Tx™  »^h  side  of  the  car,ia"e' 
Elevating-bar  (iron) J- 


Laid  on  the  carriage  over  the  rear 
notches,  and- perpendicular  to  the 
piece;  handle  to  the  left. 

One  yard  behind  the  cannoneers  of 
the  right ;  supported  upon  a  propt 
the  sponge  and  rammer -heads 
turned  from  the  parapet  and  in- 
clined slightly  from  the  piece. 

Pass-box One  yard  in  rear  of  No.  4. 


Sponge.. 
Rammer 


110  10-INCH   GUN — SERVICE. 


} 
} 


Containing  friction-primers  and  lan- 
Primer-pouch \-      yard;    suspended    from    ratchet- 
post. 

Containing  breech  sight  and  prim- 
■Gunner's  pouch [•      ing-wire;  suspended  from  ratchet- 
post. 

Chocks  (iron) One  on  each  h inter. 

Vent-cover Covering  vent. 

Tompion. In  the  muzzle. 

Shell-hooks Behind  and  near  No.  5. 

Sponge-bucket Near  sponge. 

Budorp  Mri-Pl  X  Containing  cartridges;  at  a  safe  and 

isunge  oauei j      convenient  place  near  the  piece. 

When  several  pieces  are  served  together,  there  will  be  one 
quadrant,  one  worm,  one  ladle,  one  hammer-wrench,  two  vent- 
punches,  one  gunner's  pincers,  two  lanyards  (extra),  and  two 
vent-gimlets  to  each  battery  of  not  exceeding  six  pieces.  These, 
together  with  the  primers  and  fuses,  are  kept  in  the  filling-room 
of  the  service  magazine,  where  the  shells  are  prepared  for  firing" 
mid  brought  to  the  piece  as  required. 

The  powder  is  kept  in  the  service  magazine. 

The  shells  are  strapped  to  sabots.  The  fuse-plug  is  of  metal, 
and  at  the  time  of  inserting  the  shell  into  the  piece  the  paper  or 
lead  cap  is  pulled  from  the  top  of  the  water-cap.  The  solid  shot 
are  kept  piled  convenient  to  the  piece.  All  the  projectiles  should 
be  carefully  cleansed  of  dirt,  lumps  of  rust,  or  other  protuber- 
ances before  inserting  in  the  gun.  Stands  of  grape  are  also 
provided  for  occasional  use,  and  are  kept  convenient  to  the 
piece. 

To  distribute  the  equipments, 

27S.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  mounts  upon  the  chassis;  takes  off  the  vent- 
eover,  hands  it  to  No.  2  to  place  against  the  parapet  in  rear  of 
hispo«t;  gives  the  primer-pouch  to  No.  3,  equips  himself  with 
hi-*  own  pouch,  and  clears  the  vent.  No.  4  mounts  upon  the 
chassis,  takes  the  elevating-bar,  and,  under  the  direction  of  the 
gunner,  adjusts  the  piece  conveniently  for  loading  and  resumes 
his  post,  taking  with  him  the  bar,  which  he  lays  on  the  ground 
In  ivar  of  him.  perpendicular  to  the  piece.  No.  3  equips  himself 
with  the.  primer-pouch.  The  handspikes,  when  not  in  use,  re- 
main on  the  hooks. 


10-INCH    GUN — SERVICE.  Ill 

The  instructor  causes  the  service  to  be  executed  by  the  foil  ow- 
ing commands : 

1.  From  battery. 

279.  The  gunner  places  himself  two  paces  In  rear  of  the 
chassis  and  commands:  In-GEAR.  Nos.  3  and  4  take  hand- 
spikes from  the  hooks,  embar  in  the  eccentric  sockets  of  the  top- 
carriage,  and,  assisted  by  Nos.  5  and  G,  throw  the  whorls  in  gear 
at  the  command  Heave  by  the  gunner.  The  gunner  then  com- 
mands: EMBAR.  Nos.  3  and  4  withdraw  their  handspikes  and 
insert  them  in  the  rear  and  uppermost  mortises  of  the  truck- 
wheels  ;  Nos.  5  and  G  seize  the  handspikes  with  both  hands  above 
the  hands  of  Nos.  3  and  4,  all  breaking  to  the  rear  with  the  foot, 
nearest  the  carriage.  The  gunner  then  commands:  Heave. 
Nos.  3,  4,  5,  and  6,  acting  together,  bear  down  upon  the  hand- 
spikes and  move  the  carriage  to  the  rear;  Nos.  1  and  2  follow 
up  with  the  chocks.  The  gunner  commands:  Embar.  Nos. 
5  and  6  let  go  the  handspikes;  Nos.  3  and  4  withdraw  them,  and 
embar  as  before.  The  gunner  commands:  Heave,  which  will 
be  executed  as  before.  The  commands  embar  and  heave  will  be 
repeated  by  the  gunner  until  the  face  of  the  piece  is  about  one 
yard  from  the  parapet,  when  the  gunner  commands  :  1.  Halt, 
2.  Otjt-OF-GEAR.  Nos.  1  and  2  chock  the  wheels ;  Nos.  3  and 
4  withdraw  their  handspikes,  insert  them  in  the  eccentric  sockets, 
and  at  the  command  Heave  by  the  gunner  throw  the  wheels 
out  of  gear,  leaving  the  handspikes  in  the  sockets.  All  resume 
their  posts. 

1.  By  the  numbers,  2.  Load. 

S80.  No.  2  takes  out  the  tompion,  and  places  it  by  the  para- 
pet in  rear  of  his  post.  The  gunner  mounts  upon  the  chassis 
and  closes  the  vent. 

No.  1  turns  to  his  left,  steps  over  the  sponge  and  rammer, 
faces  the  piece,  takes  the  sponge-staff  with  both  hands,  backs 
down,  the  right  hand  three  feet  from  the  sponge-head,  the  left 
hand  eighteen  inches  from  it ;  returns  to  the  piece,  raising  the 
sponge-srafF  over  the  crest  of  the  parapet ;  places  the  left  foot 
on  the  rail  of  the  chassis,  and  the  right  foot  upon  the  parapet,  or 
upon  a  step  placed  for  the  purpose  against  it ;  inserts  the  sponge- 
head  into  the  muzzle,  the  stall' in  prolongation  of  the  bore,  sup- 
ported by  the  right,  hand,  the  right  arm  extended,  the  left  hand 
hanging  naturally  by  his  side. 

No.  2  takes  a  position  on  the  left  of  the  piece  corresponding 
to  that  of  No.  1  on  the  right,  and  seizes  the  staff  with  the  left 
hand,  back  down,  near  to  and  outside  the  hand  of  No.  1. 

No.  3  faces  to  his  rear,  steps  over  the  rammer,  and,  facing 


112  10-INCH    GUN — SERVICE. 

about,  seizes  the  staff  with  both  hands,  as  prescribed  for  No.  1 
with  the  sponge;  he  then  stands  ready  to  exchange  staves  with 
No.  1. 

No.  4,  taking  the  pass-box,  goes  for  a  cartridge;  returns  and 
places  himself,  facing  the  piece,  to  the  right  and  rear  of  No.  2. 

No.  6,  taking  a  handspike,  goes  for  the  shell,  followed  by 
No.  5  with  the  shell-hooks;  No.  5  attaches  the  shell-hooks  to  the 
projectile,  and  No.  6  passes  the  handspike  through  the  ring,  or, 
if  the  shell  is  provided  with  a  rope  handle,  through  the  loop  of 
the  handle;  both  seize  the  handspike,  No.  5  in  front,  and,  bring- 
ing the  shell  up  on  the  left  of  the  piece,  place  themselves  parallel 
to  the  parapet,  No.  5  behind  and  near  No.  2. 

In  the  meanwhile,  Nos.  1  and  2  insert  the  sponge  in  the  bore 
b}T  the  following  motions,  at  the  commands  two— three— four — 
five — six : 

Two.  They  insert  the  sponge  as  far  as  the  hand  of  No.  1, 
bodies  erect,  shoulders  square. 

Three.  They  slide  their  hands  along  the  staff  and  seize  it 
at  arm's-length. 

Four.     They  force  the  sponge  down  as  prescribed  for  two. 

Five.     They  repeat  what  is  prescribed  for  three. 

Six.  They  push  the  sponge  to  the  bottom  of  the  bore.  No.  1 
replaces  the  left  hand  on  the  staff,  back  up,  six  inches  nearer  the 
muzzle  than  the  right;  No.  2  places  the  right  hand,  back  up, 
between  the  hands  of  No.  1;  both  numbers  then  change  the 
other  hand  so  as  to  seize  the  staff  back  up. 

1.  Sponge. 

281.  Nos.  1  and  2,  pressing  the  sponge  firmly  against  the 
bottom  of  the  bore,  turn  it  three  times  from  right  to  left,  and 
three  times  from  left  to  right;  drop  the  hands  farthest  from  tins 
parapet  by  their  sides,  and  withdraw  the  sponge  by  similar 
commands,  but  by  motions  contrary  to  those  prescribed  for  in- 
serting it. 

No.  2  quits  the  staff,  and,  turning  to  No.  4,  receives  from  him 
the  cartridge,  which  lie  introduces  into  the  bore ;  he  then  grasps 
the  rammer  in  the  way  prescribed  for  the  sponge. 

In  the  meanwhile,  No.  1,  turning  to  his  left,  passes  the  sponge 
above;  the  rammer  to  No.  3,  and,  receiving  the  rammer  from. 
No.  3,  presents  it  as  prescribed  for  the  sponge,  except  that,  re- 
taining hold  with  his  left  hand,  he  rests  the  rammer-head  against 
the  right  side  of  the  face  of  the  piece. 

No.  3,  as  soon  as  the  sponge  is  withdrawn,  passes  the  rammer 
in  front  of  No.  1  onto  the  parapet,  receives  the  sponge  from 
No.  1,  replaces  it  upon  the  prop,  and  resumes  his  post. 

No.  4  takes  the  cartridge  from  the  pass-box  and  hands  it  to 


10-INCH   GUN — SERVICE.  113 

No.  2,  the  choke  to  the  front;  returns  the  pass-box  to  its  place, 
and  resumes  his  post. 

Nos.  1  and  2  force  the  cartridge  home  by  the  same  commands 
and  motions  as  in  sponging. 

I.  Bam. 

282.  Nos.  1  and  2  slide  their  hands  along  the  staff  to  the 
full  extent  of  their  arms,  and,  grasping  it  firmly,  throw  the 
weight  of  their  bodies  upon  the  staff  to  force  th<»  cartridge 
tightly  home ;  No.  2  then  quits  the  rammer,  which  No.  1  throws 
out  and  lays  upon  the  parapet. 

In  the  meantime,  Nos.  5  and  6,  carrying  the  shell  as  before 
prescribed,  step  between  the  parapet  and  the  face  of  the  piece ; 
No.  6  gives  his  end  of  tin?  handspike  to  No.  2 ;  No.  5  gives  his 
hikI  to  No.  1,  and  then  places  himself  on  the  platform  in  front 
of  the  shell ;  Nos.  1  and  2  raise  the  shell  until  it  is  opposite  the 
muzzle;  No.  5,  applying  his  hands  und^r  it,  raises  the  sabot 
and  inserts  it  into  the  muzzle;  No.  5  then  resumes  his  post; 
No.  2  withdraws  the  handspike  and  passes  it  to  No.  6,  who 
replaces  it  on  tbe  hooks  and  resumes  his  post ;  No.  2  passes  the 
shell-hooks  to  No.  5,  who  replaces  them. 

Nos.  1  and  2,  taking  up  the  rammer,  apply  its  head  and  force 
the  shell  down  by  commands  and  motions  similar  to  those  pre- 
scribed for  the  cartridge;  at  the  command  Ram  it  is  pressed 
tightly  down  against  the  cartridge;  No.  2  quits  the  rammer  and 
resumes  his  post;  No.  1  throws  out  the  rammer,  replaces  it  on 
the  prop,  and  resumes  his  post. 

As  soon  as  No.  4  has  delivered  the  cartridge,  he  mounts  upon 
the  chassis,  embars  through  the  ratchet-post  with  the  elevating- 
bar,  and,  when  the  projectile  is  home,  gives  the  piece  an  eleva- 
tion of  about  5  degrees, — this  for  the  purpose  of  preventing  the 
displacement  of  the  projectile  when  the  piece  is  run  into  battery; 
No.  4  replaces  the  elevating-bar  and  resumes  his  post ;  the  gun- 
ner pricks,  leaving  the  priming-wire  in  the  vent. 

1.  In  battery. 

283.  The  gunner  commands:  In- GEAR.  Nos.  1  and  2  un~ 
chock  the  wheels  and  place  the  chocks  on  the  hurters;  Nos.  3 
and  4  seize  the  handspike  and,  at  the  command  Heave  by  the 
•junner,  bear  down  slowly  until  the  piece  is  in  motion,  regulat- 
.ugit  by  alternately  throwing  the  wheels  in  and  out  of  gear,  or 
partially  so.  As  soon  as  the  carriage  strikes  the  hurters,  the 
?uuner  commands :  1.  Out-of-gear,  2.  Heave.  Nos.  3  and 
1  throw  the  wheels  out  of  gear,  withdraw  their  handspikes,  re- 
dace  them  on  the  hooks,  and  resume  their  posts.  If  the  car- 
nage does  not  move  when  in  gear,  the  gunner  directs  No.  3  to 

8 


114  10-INCH   GUN — SERVICE. 

slightly  engage  a  handspike  in  a  rear  mortise  of  the  truck-wheel 
and  gently  urge  the  carriage  forward.  Care  must  be  exercised 
in  this  operation  that  the  handspike  does  not  fly  forward  with 
violence. 

As  soon  as  the  carriage  strikes  the  hurters,  Nos.  1  and  2  lock 
the  wheels  with  the  toggles. 

1.  Aim. 

284.  The  gunner  commands:  1.  Chassis  in-gear,  2. 
Heave.  At  the  first  command,  Nos.  3  and  4  embar  in  the 
sockets  of  the  eccentrics,  and  at  the  second  command,  assisted 
b}r  Nos.  1  and  2,  throw  the  chassis-wheels  in  gear,  and,  leaving 
the  handspikes  in  the  sockets,  resume  their  posts ;  Nos.  5  and  6 
embar  in  the  traverse-wheels.  The  gunner  withdraws  the  prim- 
ing-wire, places  the  breech  sight  in  the  socket,  and,  sighting 
through  it,  gives  the  direction ;  Nos.  5  and  6  move  the  trail  to 
the  left  or  right  at  the  command  left  or  right  from  the  gunner. 

When  the  direction  has  been  given,  the  gunner  commands  : 
1.  Chassis  out-of-gear,  2.  Heave.  At  the  first  command, 
Nos.  1  and  2  seize  the  handspikes,  and  at  the  second  throw  the 
wheels  out  of  gear,  return  the  handspikes  to  their  hooks,  and 
resume  their  posts.  Nos.  5  and  6  unbar,  return  their  hand- 
spikes to  the  hooks,  and  resume  their  posts. 

No.  3  passes  the  hook  of  the  lanyard  through  the  eye  of  a 
primer,  holds  the  handle  of  the  lanyard  with  the  right  hand, 
the  hook  between  the  thumb  and  forefinger,  and  stands  ready 
to  hand  it  to  the  gunner.  No.  4  mounts  upon  the  chassis  and, 
embarring  through  the  ratchet-post  with  the  elevating-bar,  raises 
or  lowers  the  breech  as  directed  by  the  gunner. 

When  the  piece  is  correctly  aimed,  the  gunner  commands  : 
Ready,  makes  a  signal  with  both  hands,  removes  the  breech 
sight  with  his  left  hand,  and,  receiving  the  primer  from  No.  3  in 
his  right,  inserts  it  in  the  vent,  dismounts  from  the  chassis,  and 
goes  where  he  can  best  observe  the  effect  of  the  shot;  Nos.  1  and 
2  break  off  sideways  with  the  foot  farthest  from  the  parapet ; 
No.  3  drops  the  handle,  allowing  the  lanyard  to  pass  through  his 
fingers,  steps  back  obliquely  three  yards  to  the  rear,  and  breaks 
off  to  his  left  and  rear  with  the  left  foot,  left  hand  hanging  nat- 
urally by  the  side ;  No.  4  resumes  his  post,  taking  with  him  the 
elevating-bar,  which  he  lays  on  the  ground  as  before. 

1.  Number  one  (or  the  like),  2.  Fire. 

285.  No.  3,  turning  his  face  from  the  piece,  pulls  the  lan- 
yard quickly,  but  steadily,  and  lires.  Immediately  after  the  dis- 
charge, Nos.  1,  2,  and  3  resume  the  erect  position  ;  No.  3  rewinds 
the  lanyard  and  replaces  it  in  the  pouch.  The  gunner,  having 
observed  the  effect  of  the  shot,  returns  to  his  post. 


100-POUNDER  PARROTT — SERVICE.  115 

To  load  without  the  numbers^  and  to  fire* 
As  explained  in  par.  245. 

To  load  and  fire  continuously,  and  to  cease  firing. 
As  explained  in  pars.  246  and  247. 

To  secure  the  piece* 
As  explained  in  par.  249. 

To  replace  equipments. 

286.  Executed  as  in  par.  250,  except  that  the  gunner  re- 
places the  pouches  on  the  ratchet-post,  instead  of  the  knob  of 
the  cascable. 

Note  1. — The  piece  may  be  fired  with  safety  when  the  chassis 
is  in  gear.  This  part  of  the  prescribed  service  may,  therefore, 
be  omitted. 

2.  The  flooring-planks  extend  over  but  a  portion  of  the  chassis, 
making  it  exceedingly  inconvenient  to  load  the  piece  when  in 
its  proper  position.  To  remedy  this  defect,  cut  boards  to  the 
proper  length  and  fit  them  in  cross  ways  between  the  rails  of  the 
chassis,  resting  on  the  lower  flanges  of  the  rails. 

3.  Solid  shot  for  this  piece  arc  without  ears ;  they  cannot,  there- 
fore, be  carried  by  means  of  shell-hooks.  The  ladle  for  hot  shot 
(sometimes  to  be  found  at  posts)  answers  for  carrying  and  lifting 
the  shot  to  the  muzzle. 

Service  of  the  100-pounder  Pabrott. 

287.  The  100-pounder  Parrott  rifle  is  mounted  on  a  carriage 
of  similar  construction  to  that  of  the  10-inch  smooth-bore,  and  the 
service  of  it  is  nearly  identical  with  the  foregoing,  except  that, 
in  bringing  up  the  projectile,  a  rope  strap  is  used  instead  of  shell- 
hooks;  and  excepting,  also,  that  in  pointing,  No.  4,  instead  of 
using  an  elevating-bar,  assists  the  gunner  in  giving  the  elevation 
by  means  of  the  elevating  screw. 

Remarks. 

288.  All  guns  of  the  Parrott  system  are  of  cast-iron,  rein- 
forced at  the  seat  of  the  charge  by  a  wrought-iron  jacket,  which 
is  shrunk  on.  The  one,  two,  and  three  hundred  pounders  have 
no  preponderance.  The  depth  of  grooves  in  all  of  them  is  0.10 
inch,  with  increasing  twist. 

The  300-pounder  weighs  26,000  pounds  ;  has  15  grooves.  The 
200-pouuder  weighs  16,300  pounds;  has  11  grooves.  The  100- 
pounder  weighs  9,700  pounds ;  has  9  grooves.    The  charge  for 


116 


100-POUNDER   PARROTT — SERVICE. 


the  first  is  25  pounds,  for  the  second  16  pounds  hexagonal,  and 
for  the  third  10  pounds  cannon  powder. 

Ranges:  100-poundcr. 

Charge :  10  pounds  cannon  powder.  Projectile  :  Parrott  shell, 
filled,  100  pounds.    Initial  velocity :  1.080  feet. 


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10-INCH  GUN — CASEMATE — SERVICE.  117 

389.  When  a  gun,  mounted  on  an  iron  carriage,  is  loaded, 
and  it  is  not  desired  to  fire  it,  the  projectile  may  be  withdrawn 
by  running  the  piece  from  battery,  depressing  tiie  muzzle  as  far 
as  possible,  and  then  allowing  it  to  run  into  battery  against  the 
hurters,  thus  jarring  the  projectile  forward. 

The  cartridge  is  withdrawn  with  the  worm ;  should  it  burst, 
the  powder  is  scooped  out  with  the  ladle. 

290.  In  all  carriages  for  heavy  guns,  when  no  means  for 
checking  the  recoil  are  provided,  the  rails  should  be  sanded,  but 
the  sand  should  be  free  from  gravel. 


Service  of  a  10-inch  Smooth-bore  Gtjn  in  casemate. 

Description  of  piece. 

Identical  with  the  same  gun  in  barbette,  as  given  in  par.  276. 

Carriage,  wrought-iron  (chassis  and  top);  front  pintle;  with- 
out air-cylinders  or  other  recoil  check.  Weight  of  top-carriage, 
1500  pounds ;  weight  of  chassis,  3000  pounds. 

The  piece,  when  in  battery,  in  the  ordinary  casemate  embra- 
sure, admits  of  7  degrees  elevation  and  6  degrees  depression. 

The  new-pattern  carriage  and  chassis  will  be  provided  with 
air-cylinders.  The  former  will  weigh  1459  pounds ;  the  latter, 
5310  pounds. 

The  ranges  are  identical  with  the  same  gun  in  barbette.  (Par. 
276.)  The  ammunition  is  the  same,  and  is  kept  and  served  in 
the  same  manner.    (Par.  277.) 

To  serve  the  piece. 

291.  Eight  men  are  necessary :  one  chief-of-detachment,  one 
gunner,  and  six  cannoneers.  The  implements  and  equipments 
are  arranged  as  specified  in  par.  277. 

To  distribute  the  equipments. 

292.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  steps  to  the  side  of  the  chassis,  takes  off  the  vent- 
cover,  hands  it  to  No.  2  to  place  against  the  scarp  in  rear  of 
his  post,  gives  the  primer-pouch  to  No.  3,  equips  himself  with 
his  own  pouch,  and  clears  the  vent.  No.  4  mounts  upon  the 
chassis,  takes  the  elevating-bar  and,  under  the  direction  of  the 


118  10-INCH   GUN — CASEMATE — SERVICE. 

gunner,  adjusts  the  piece  conveniently  for  loading,  and  resumes 
his  post,  taking  with  him  the  bar,  which  he  lays  on  the  pave- 
ment in  rear  of  his  post,  perpendicular  to  the  piece. 

$o.  3  equips  himself  with  the  primer-pouch.  The  handspikes* 
when  not  in  use,  remain  on  the  hooks. 

To  serve  the  piece. 

The  instructor  commands : 

1.  From  battery. 
Executed  as  in  par.  279. 

1.  By  the  numbers,  2.  LOAD. 

Executed  as  in  par.  280,  except  that  Nos.  1  and  3  pass  the 
sponge  and  rammer  staves  into  the  embrasure,  instead  of  over 
the  crest  of  the  parapet. 

1.  Sponge. 

Executed  as  in  par.  281. 

1.  Bam. 

Executed  as  in  par.  282,  except  that  No.  1  lays  the  rammer- 
staff  upon  the  sole  of  the  embrasure,  instead  of  on  the  parapet. 

1.  IN  BATTERY. 

Executed  as  in  par.  283. 

1.  Aim. 

m 

Nos.  5  and  6  embar  in  the  rear  traverse-wheels.  The  gunner, 
mounting  upon  the  chassis,  withdraws  the  priming-wire,  places 
the  breech  sight  in  the  socket,  and  gives  the  direction.  Nos.  5 
and  6  will,  when  necessary,  be  assisted  by  Nos.  1  and  2. 

The  remaining  operations  of  pointing  are  as  explained  in  par. 
284. 

1.  Number  one  (or  the  like),  2.  Fire. 

Executed  as  in  par.  285. 

To  load  without  the  numbers,  and  to  fire. 

To  load  and  fire  continuously,  and  to  cease  firing,  and  to  *e- 

cure  the  piece. 

All  executed  as  in  pars.  245,  246,  247,  and  286. 


15-INCH    GUN — CENTRE   PINTLE — SERVICE.  119 


Service  of  a  15-inch  Gun  mounted  on  a  centre- 
pintle  CARRIAGE. 
Description  of  piece. 
293*  Gun,  cast-iron ;  muzzle-loader;  smooth-bore. 


Designation. 


Calibre 

Weight 

Preponderance 

Length  of  piece 

Length  of  bore  (calibres) 

Maximum  diameter 

Minimum  diameter 

Windage 

Charge  (mammoth  or  hexagonal  powder)  for 

shot 

"       for  shell 

Solid  shot 

Shell  (unfilled) 

Initial  velocity  (feet) 

Weight  of  top-carriage 

Weight  of  chassis 

Carriage — wrought-iron  (chassis  with  two  air- 
cylinders  to  check  recoil) 


No. 


11 


1.534 


Lbs. 


Kanges  in  yards. 


INCH. 


15 


49,000 

00 

1 

190 

1 

48 

•  ■  •  ■  •■ 

25 

0.13 

100 

60 

450 

■•••«• 

330 

5,800 

' 

15,450 

r 

Shot. 

Shell. 

a 

c 

• 

Q 

o 

«M    bt) 

3 

a 
> 
© 

• 

1 

f-H 

• 

a 

3 

1 

Charge. 

,  Deg's. 

Y'rds. 

Deg's. 

Y'rds. 

Sees. 

100  pounds  of    mammoth 

!      i 

769 

1 

600 

1.44 

powder  for  solid  shot,  and 

1         2 

1332 

2 

1073 

2.79 

60  pounds  for  shell. 

3 

1819 

3 

1467 

4.1 

4 

2235 

4 

1800 

5.28 

To    fill  shell:    12   pounds  of 

5 

2601 

5 

2094 

6.41 

mortar  powder. 

6 

2926 

6 

2355 

7.58 

7 

3221 

7 

2590 

8.G7 

Pressure  per  square  inch,  av- 

8 

3491 

8 

2804 

9.68 

erage,  19,500  pounds. 

9 

3735 

9 

3C00 

10.69 

10 

3959 

10 

3171 

11.63 

Length  of  cartridge : 

15 

4830 

15 

3916 

16.30 

100  pounds=30  inches. 

20 

5579 

20 

4458 

20.52 

60  pounds=18  inches. 

1 

120         15-INCH   GUN — CENTRE   PINTLE — SERVICE. 


Counterpoise  handspikes 
(iron) 


Elevating-bar  (iron) 


The  piece  admits  of  25  degrees  elevation  and  6  degrees  depres- 
sion.    The  platform  is  a  permanent  portion  of  the  work. 

To  serve  the  piece. 

294.  Twelve  men  are  required :  one  chief-of-detachment,  one 
gunner,  and  ten  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 

One  on  each  side  of  piece,  attached 
to  socket  on  front  axle  by  a  set- 
screw.  A  rope  is  attached  to  the 
small  end  of  these  handspikes  for 
heaving  on  when  running  the 
piece  from  battery.  When  not 
in  use.  the  free  end  of  the  rope  is 
hung  by  an  eye  to  a  hook  on  the 
cheek  of  the  carriage. 

Truck  handsnikes  flron}     \  Two  on  eadl  si(le  of  piece ;  OM  ,,ooks 
irucK  nancispiKes  (uonj...  |      |ipQn  fche  g.(]es  of  t|)e  cna?sis 

Lying  on  the  carriage,  upon  the 
rear  notches,  and  perpendicular 
to  the  piece,  handle  to  the  left. 

One  yard  behind  the  cannoneers  of 
the  right;  the  sponge  and  ram- 
mer-heads turned  from  the  para- 
pet, inclined  slightly  from  the 
piece,  and  supported  on  a  prop. 

Pass-box Two  yards  in  rear  of  No.  7. 

Containing    friction  -  primers   and 

Primer-pouch }»      lanyard;    hung   on   step   of   the 

ratchet-post. 

Containing  breech  sight  and  prim- 
ing-wire ;  hung  on  step  of  ratchet- 
post. 

Chocks  (iron) One  on  each  hurter. 

Vent-cover Covering  vent. 

Tompiou In  muzzle. 

Carrying-bar  (wood) Two  yards  in  rear  of  No.  10. 

Shell-hooks Two  yards  in  rear  of  No.  4> 

Sponge-bucket Near  sponge. 

Differential  pulley,  —or  \  Attached  to  the  crane 
blocks  and  tackle /  Attacnecl  t0  tne  crane- 

There  not  being  sufficient  space  for  them  when  the  carriage 


Sponge .. . 
Rammer 


Gunner's  pouch 


15-INCH   GUN — CENTRE   PINTLE — SERVICE.         121 

runs  from  battery,  neither  handspikes,  elevating-bar,  nor  any 
equipments  will  be  placed  on  the  floor-boards  of  the  chassis. 

When  several  pieces  are  served  together,  then?  will  be  one 
quadrant,  one  worm*  one  ladle,  one  hammer-wrench,  two  vent- 
punches,  one  gunner's  pincers*  two  lanyards  (extra),  and  two 
tent-gimlets  to  each  battery  of  not  exceeding  six  pieces.  These 
will  be  kept  in  the  filling-room  of  the  service  magazine. 

The  cartridges  are  in  the  service  magazine,  and  are  brought 
to  the  piece  as  wanted.  The  shells  are  in  the  filling-room  of  the 
service  magazine,  and  are  likewise  brought  up  when  required. 
The  shells  are  strapped  to  sabots.  The  fuse-plugs  are  of  metal, 
and  at  the  time  of  inserting  the  shell  into  the  piece  the  paper  cap 
should  be  pulled  from  the  top  of  the  fuse-primer.  The  solid  shot 
are  kept  convenient  to  the  piece.  The  projectiles  should  be 
carefully  freed  from  dirt,  lumps  of  rust,  or  any  other  protuber- 
ances that  might  prevent  their  easy  insertion  into  the  bore  of 
the  piece. 

To  distribute  the  equipments. 

295.  The  instructor  commands : 

1.  Take  equipments. 

The  gunner  mounts  upon  the  chassis,  takes  off  the  vent- 
cover,  hands  it  to  No.  2,  who  places  it  against  the  parapet,  near 
his  post ;  gives  the  primer-pouch  to  No.  3,  equips  himself  with 
his  own  pouch,  and  clears  the  vent;  Nos.  1  and  2  remove  the 
plugs  from  the  front  ends  of  the  air-cylinders. 

Nos.  5  and  6  hook  the  ropes  to  the  counterpoise  handspikes, 
and,  securing  the  free  end  to  the  hooks  on  the  cheeks,  mount 
upon  the  chassis.  Under  the  direction  of  the  gunner,  No.  6 
takes  the  elevating -bar,  embars  with  it  through  the  ratchet- 
post,  and,  assisted  by  No.  5,  gives  the  piece  an  elevation  of  about 
one  degree;  replaces  the  elevating-bar,  and,  together  with  No. 
5  and  the  gunner,  resumes  Ins  post. 

The  service  of  the  piece  is  executed  as  follows.  The  instructor 
commands : 

1.  From  battery. 

296.  The  gunner  mounts  upon  the  chassis,  and  commands: 

IN-GEAR. 

Nos.  3  and  4  adjust  the  pawls  of  the  counterpoise  handspikes 
bo  that  they  will  clear  the  ratchets  of  the  truck-wheels ;  Nos.  5 
and  6  take  down  the  ropes  and  raise  the  handspikes  until  Nos.  3 
and  4  engage  the  pawls  in  the  ratchets. 

In  the  meanwhile,  Nos.  9  and  10  insert  each  a  handspike  into 
the  sockets  of  the  rear  truck-wheels,  and,  mounting  upon  the 


122         15-INCH   GUN — CENTRE  PINTLE — SERVICK. 

steps  of  the  chassis,  unlock  the  rear  axle,  and  at  the  command 
Heave  from  the  gunner,  assisted  by  Nos.  7  and  8,  throw  the 
rear  truck-wheels  in  gear. 

Xos.  9  and  10  relock  the  axlo,  and  return  the  handspikes  to 
the  hooks. 

The  gunner  then  commands :  Embar. 

No*.  5  and  6  raise  the  counterpoise  handspikes  until  nearly 
vertical,  when  Nos.  3  and  4  engage  the  pawls  into  the  ratchets. 

Nos.  3  and  5  seize  the  counterpoise  handspikes,  aud  Nos.  7 
and  9  the  ropes  on  the  right  of  the  piece ;  and  Xos.  4.  6.  8,  and 
10  apply  themselves,  in  like  manner,  upon  the  left.  All  take 
hold  from  front  to  rear  in  the  ascending  order  of  their  numbers. 

At  the  command  Heave  from  the  gunner,  the  handspikes  are 
forced  down,  and  the  top-carriage  moves  a  short  distance  to  the 
rear. 

Nos.  1  and  2  follow  up  the  movement,  and  keep  the  wheel- 
chocks  closely  applied  to  the  wheels.  The  gunner  gives  alter- 
nately the  commands  embar  and  heave,  until  the  muzzle  of  the 
piece  is  over  the  front  part  of  the  chassis;  he  then  commands: 
Halt.  At  this  command,  Nos.  3  and  4  clear  the  pawls  from  the 
ratchets,  and  Nos.  5  and  6  raise  the  handspikes  and  secure  the 
ropes  to  the  hooks. 

The  gunner  then  commands:  Out-OF-GEAR.  Nos.  9  and  10 
mount  upon  the  steps  of  the  chassis,  unlock  the  axle,  and,  at  tin; 
command  Heave  from  the  gunner,  throw  the  wheels  out  of  gear, 
and,  leaving  the  handspikes  in  the  sockets,  resume  their  posts. 

1.  By  the  numbers,  2.  Load. 

29*7.  Nos.  1  and  2  mount  upon  the  front  of  the  chassis  and 
upon  the  steps  of  the  parapet  wall ;  No.  2  removes  the  tompion 
and  I  lands  it  to  No.  4,  who  places  it  against  the  parapet,  in  rear 
of  the  post  of  No.  2. 

No.  3  brings  up  the  sponge,  passes  it  to  No.  1,  and  mounts 
upon  the  steps  of  the  parapet  wall,  outside  of  No.  1,  to  assist 
Nos.  1  and  2  in  sponging  and  ramming.  The  sponge-head  is 
inserted  in  the  muzzle. 

No.  5,  bringing  up  the  rammer  behind  No.  1,  stands  ready  to 
hand  it  to  No.  3.  and  to  take  the  sponge  from  No.  3  after  the 
sponging  is  completed. 

Nos.  7  and  9,  taking  the  pass-box,  go  for  the  cartridge ;  Nos. 
4,  6,  8,  aud  10  go  for  the  projectile,  No.  4  carrying  the  shell- 
hooks  and  No.  10  the  carrying-bar.  I\\  returning,  the  projectile 
is  brought  up  on  the  left  of  the  piece,  No.  4  in  advance  and  the 
other  numbers  in  their  order  in  rear.  The  cartridge,  in  the 
pass-box,  is  brought  up  on  the  right  of  the  piece. 


15-INCH   GUN — CENTRE   PINTLE — SERVICE.         V2S 

m 

The  projectile  is  placed  under  the  crane ;  the  carrying-bar  re- 
turned to  its  place  by  No.  10,  who  then  resumes  his  post;  the 
pulley  is  attached  to  the  shell-hooks  by  No.  4;  Nos.  6  and  8  rim 
up  the  projectile,  No.  4  steadying  it.  In  the  meanwhile — the- 
gunner  stopping  the  vent — the  sponging  is  executed  by  Nos.  1 
and  2,  assisted  by  No.  3,  at  commands  from  the  instructor  of 
two — three— four,  <fcc. 

Two.  Insert  the  sponge  as  far  as  the  hand  of  No.  1,  bodies 
erect,  shoulders  square. 

Three.  Slide  the  hand  along  the  staff'  and  seize  it  at  arm's- 
length. 

Four.    Force  the  sponge  down  as  prescribed  for  two. 

Five.    Repeat  what  was  done  at  three. 

Six.  Push  the  sponge  to  the  bottom  of  the  bore.  No.  1  seizes- 
the  staff  with  the  left  hand,  back  up,  six  inches  nearer  the  muz- 
zle'than  the  right;  No. 2  places  the  right  hand,  back  up,  between 
the  hands  of  No.  1 ;  both  then  change  their  other  hands  so  as  to- 
grasp  the  staff  with  backs  up. 

1.  Sponge. 

29S.  Nos.  1,  2,  and  3,  pressing  the  sponge  firmly  against  the 
bottom  of  the  bore,  turn  it  three  times  from  right  to  left,  and 
three  times  from  left  to  right.  The  sponge  is  withdrawn  at  the 
commands  two — three— four— jive,  &c,  by  motions  contrary  to- 
those  prescribed  for  inserting  it.  As  soon  as  the  sponge  is  with- 
drawn, No.  3,  turning  towards  the  left,  passes  the  sponge,  with 
both  hands,  behind  No.  1  to  No.  5,  and  receives  from  him  the 
rammer;  Nos.  1  and  2  take  the  cartridge  from  Nos.  7  and  9, 
and  insert  it  in  the  bore;  Nos.  7  and  9  replace  the  pass-box  and 
resume  their  posts ;  No.  5  replaces  the  sponge  on  the  prop  and 
resumes  his  post ;  as  soon  as  the  cartridge  is  inserted,  No.  3  places 
the  rammer-head  against  it  in  the  bore.  The  cartridge  is  forced 
down  by  Nos.  1,  2,  and  3,  at  the  commands  and  by  the  motions 
prescribed  for  the  sponge. 

1.  Bam. 

299.  The  cartridge  is  set  home  by  strong  pressure,  not  by  a 
blow ;  Nor.  1  and  3  throw  out  the  rammer;  No.  2,  quitting  the 
staff,  assists  No.  4  in  swinging  the  crane  round  to  bring  the 
irojectile  in  front  of  the  muzzle ;  the  rammer-head  is  placed 
gainst  the  projectile,  which  is  pushed  into  the  bore  by  Nos.  1, 
u  3,  and  4;  No.  4  withdraws  the  shell-hooks,  and  resumes  his 
)ost;  Nos.  1,  2,  and  3  force  the  projectile  home  by  motions  and 
ommands  as  explained  for  the  cartridge;  Nos.  G  and  8  swing 
he  crane  back;  secure  it  and  the  pulley  against  the  cheek;  No- 


124  15-INCH   GUN CENTRE   PINTLE — SERVICE. 

• 

$  resumes  his  post,  and  No.  6  mounts  upon  the  chassis.  The 
rammer  is  thrown  out  and  passed  by  No.  3  to  No.  5,  who  places 
it  on  the  prop;  Nos.  1,  2,  3,  and  5  then  resume  their  posts.  The 
gunner,  assisted  by  No.  6,  gives  the  piece  an  elevation  of  about 
five  degrees,  after  which  he  pricks  the  cartridge,  leaving  the 
priming-wire  in  the  vent.     No.  6  resumes  his  post. 

1.  In  battery. 

300.  The  gunner  commands:  In-gear.  Nos.  1  and  2  un- 
chock  the  wheels;  Nos.  3  and  4  see  thai  the  handspike  pawls 
are  clear  of  the  ratchets;  Nos.  9  and  10  mount  upon  the  steps, 
unlock  the  axle,  seize  the  rear  handspikes,  and,  at  the  command 
Heave  b}r  the  gunner,  bear  down  slowly  (assisted  if  necessary 
by  V  and  8)  until  the  piece  is  in  motion,  and  regulate  it  by  alter- 
nately throwing  the  wheels  in  and  out  of  gear  sufficiently  for 
that  purpose.  The  front  wheels  are  not  chocked  by  Nos.  1  and 
2  unless  the  gunner  so  directs.  As  soon  as  the  carriage  strikes 
the  hurter,  the  gunner  commands :  1.  Out-of-gear,  2.  Heave. 
Nos.  9  and  10  throw  the  wheels  out  of  gear,  secure  the  axle  with 
the  pawl,  and,  returning  the  handspikes  to  the  hooks  on  the 
•chassis,  resume  their  posts. 

Should  the  carriage  not  move  when  the  wheels  are  thrown  in 
gear,  the  gunner  directs  Nos.  3,  4,  o,  and  6  to  lower  the  hand- 
spikes and  engage  the  upper  arm  of  the  handspike  pawl  in  the 
ratchet,  and  by  raising  the  handspike  urge  the  piece  forward. 

1.  Aim. 

301.  The  gunner  commands:  1.  Chassis  in-gear,  2. 
Heave.  Nos.  7  and  8  take  the  handspikes,  embar  in  the  sock- 
ets of  the  eccentrics  of  the  chassis,  and,  assisted  by  Nos.  9  and 
10,  throw  the  wheels  in  gear;  they  then  embar  with  the  same 
handspikes  in  the  mortises  of  the  rear  set  of  the  front  traverse- 
wheels  ;  Nos.  1  and  2  embar  in  the  front  set ;  Nos.  5  and  6 
mount  on  the  chassis  to  assist  the  gunner  in  giving  the  eleva- 
tion ;  No.  3  passes  the  hook  of  the  lanyard  through  the  eye  of  a 
primer,  and  stands  ready  to  hand  it  to  the  gunner. 

The  gunner  places  the  breech  sight  in  the  socket,  and,  sight- 
ing through  if,  gives  the  direction,  commanding:  MUZZLE 
right,  or  Muzzle  left,  for  Nos.  1,  2,  7,  and  8  to  traverse  the 
chassis  to  the  right  or  to  the  left. 

The  direction  being  given,  the  gunner  commands:  1.  CHAS- 
SIS out-of-gear,  2.  Heave.  At  the  first  command,  Nos.  1 
and  2  return  their  handspikes  to  their  hooks  and  resume  their 
posts;  Nos.  7  and  8  embar  in  the  sockets  of  the  eccentrics  of 
the  chassis,  and,  assisted  by  Nos.  9  and  10,  at  the  command 


15-INCH   GUN — CENTRE   PINTLE — SERVICE.         125 

heave  throw  the  chassis  out  of  gear;  Nos.  7  and  8  then  replace 
their  handspikes,  and,  with  Nop.  9  and  10,  resume  their  posts. 

Note. — The  piece  can  he  tired  with  safety  when  the  chassis  is 
in  gear.  The  omission  of  this  part  of  the  exercise  saves  much 
time  and  labor. 

The  gunner  next  causes  No.  6,  assisted  by  No.  5,  to  give  tiie 
required  elevation  to  the  piece,  and  commands  :  Ready.  Nos. 
5  and  6  resume  their  posts,  No.  6  taking  with  him  the  elevating- 
bar,  which  he  places  in  rear  of  him  on  the  ground,  perpendicular 
to  the  piece.  The  gunner  withdraws  the  priming-wire,  receives 
the  primer  from  No.  3,  inserts  it  in  the  vent,  takes  the  breech- 
sight  with  him,  and  goes  where  he  can  best  observe  the  eftect  of 
the  shot. 

The  chief-of-detachment,  or  in  his  absence  the  gunner,  then 
commands:  1.  Detachment  rear,  2.  March.  At  the  first 
command,  the  cannoneers,  except  No.  3,  face  from  the  epaul- 
ment,  and,  at  the  command  march,  they  march  to  the  rear  as 
explained  in  par.  113;  No.  3  drops  the  handle,  allowing  the 
lanyard  to  pass  through  his  fingers,  and  steps  back  three  yards 
obliquely  from  the  piece,  breaks  off  with  his  left  foot  to  his  left 
and  rear,  the  left  hand  by  the  side. 

1.  Number  one  (or  the  like),  2.  Fire. 

302.  No.  3,  turning  his  face  from  the  piece,  pulls  the  lan- 
yard quickly,  but  steadily,  and  fires;  immediately  after  the  dis- 
charge he  resumes  the  erect  position ;  rewinding  his  lanyard v 
returns  it  to  his  pouch  and  joins  his  detachment.  The  gunner, 
having  observed  the  effect  of  the  shot,  returns  to  his  post. 

As  soon  as  the  piece  is  discharged,  unless  otherwise  directed, 
the  cannoneers  resume  their  posts  by  command  of  the  chief-of- 
detachment,  or  in  his  absence  the  gunner :  1.  Cannoneers  to  your 
posts,  2.  Right,  3.  Face,  4.  MARCH.    Executed  as  explained  in 
par.  108. 

To  load  without  the  numbers,  and  to  fire. 

303.  Executed  as  prescribed  mpar.  245. 

To  load  and  fire  continuously,  and  to  cease  firing. 

304.  Executed  as  explained  in  pars.  246  and  247. 

When  the  piece  is  loaded,  and  it  is  not  desired  to  fire  it,  the 
charge  is  withdrawn  as  explained  in  par.  289. 

To  secure  the  piece. 

305.  Executed  as  explained  in  par.  286,  adding: 

The  gunner  hangs  the  pouches  on  the  ratchet-post,  Nos.  1  and 


126  15-INCH    GUN — FRONT    PINTLE — SERVICE. 

2  replace  the  plugs  in  the  front  ends  of  the  air-cylinders,  and 
Nos.  5  and  6  detach  the  ropes  from  the  handspikes. 

Service  of  a  15-inch  Gun  mounted  on  a  front- 
pintle  CARRIAGE. 

Description  of  piece. 

306o  This  piece  is  identical  with  the  same  gun  mounted  on 
*i  centre-pintle  carriage.     (Par.  293.) 

The  top-carriage  is  the  same  in  both  cases;  the  chassis  alone 
differs. 

Weight  of  front-pintle  chassis,  including  geared  traverse- 
wliccls,  17,000  pounds. 

There  are  two  kinds  of  geared  traverse-wheels,  differing,  how- 
-ever,  only  in  height  and  weight.  The  axis  of  the  trunnions  of. 
the  gun  mounted  on  the  highest  is  8  feet  5.25  inches  above  the 
pintle-block,  and  10 feet  11.25  inches  above  the  terre-plein.  Upon 
the  other  carriage  it  is  7  feet  2.25  inches  above  the  pintle-block, 
and  9  feet  5.25  inches  above  the  terre-plein. 

The  piece  admits  of  25  degrees  elevation  and  6  degrees  de- 
pression. 

The  platform  is  a  permanent  part  of  the  work. 

The  ranges  are  as  given  in  par.  293. 

The  same  number  of  men  are  required  as  for  the  gun  mounted 
■on  a  centre-pintle  carriage.  The  implements  and  equipments 
4i re  likewise  the  same. 

Service  of  the  piece. 

3©?.  Executed  'as  for  the  centre-pintle  carriage  {pars.  295 
to  305),  except  as  follows  : 

1st.  After  what  is  prescribed  under  the  head  ram  has  been 
-completed,  and  before  the  piece  is  run  into  battery,  the  gunner 
commands  :  1.  Chassis  in-gear,  2.  Heave.  At  the  first  com- 
mand, Nos.  3  and  4  embar  with  the  handspikes  in  the  sockets 
of  the  chassis  eccentrics,  and  at  the  second  command,  assisted 
by  Nos.  1,2,  7,  and  8,  throw  the  wheels  in  gear. 

2d.  At  the  command  aim^  the  direction  is  given  (under  the 
direction  of  the  gunner)  by  Nos.  7,  8,  9,  and  10,  who  man  the 
cranks  of  the  geared  traverse-wheels.  At  I  he  command  CHASSIS 
■OUT-OF-GEAR,  Heave,  the  chassis  is  thrown  out,  of  gear  by  Nos. 
1,  2,  3,  4,  7,  and  8,  Nos.  3  and  4  embarring  with  the  handspikes. 

The  piece  is  then  run  into  battery  as  explained  in  par.  300; 


15-INCH   GUN — FRONT   PINTLE — SERVICE.         127 

alter  which  the  elevation  is  given  as  explained  in  same  para- 
graph. 

jfrote. — The  piece  can  be  fired  with  safety  when  the  chassis  is 
in  gear.  The  omission  ol  this  part  ol  the  exercise  saves  ranch 
time  and  labor. 

Remarks. 

308,  The  foregoing  instructions,  for  both  the  front  and  the 
centre  pintle  carriages,  are  for  those  of  the  most  recent  model. 
There  arc,  however,  in  service,  various  patterns, — steps  in  im- 
provement,—the  chief  difference  between  them  being  in  the 
arrangement  of  the  means  lor  running  the  piece  from  and  into 
battery.  Only  slight  modifications  in  the  foregoing  instructions 
are  necessary  to  adapt  them  to  any  ol  the  patterns,  and  these 
will  readily  suggest  themselves  to  the  instructor. 

The  front  axle  ol  the  top-carriage  is  not  eccentric ;  the  rear 
one  is.  The  front  part  of  the  sole  of  each  shoe  is  cut  away  to  a 
point  a  few  inches  in  rear  ol  the  front  axle,  and  to  a  depth  of 
about  half  an  inch.  When  the  rear  wheels  are  out  of  gear,  the 
front  wheels  do  not  touch  the  chassis  rails ;  but  when  the  rear 
wheels  are  thrown  into  gear,  the  rear  part  of  the  carriage  is 
slightly  raised,  and  the  front  part  of  the  carriage  is,  in  conse- 
quence of  the  soles  being  cut  away,  lowered ;  the  front  wheels 
then  touch  the  chassis  mils  and  support  the  weight  of  the  front 
part  of  the  carriage,  and  the  whole  moves  with  rolling  friction 
upon  the  front  and  rear  truck-wheels.  The  wheels  are  out  ol 
gear  when  the  gun  is  fired ;  the  recoil  is  then  on  sliding  fric- 
tion. 

The  front  axle  is  furnished,  at  each  end,  with  a  brass  sleeve, 
to  which  the  counterpoise  handspike  is  firmly  attached.  A  pawl 
is  attached  to  the  handspike,  and  eugages  into  ratchets  in  the 
truck-wheels.  Bearing  down  upon  the  handspikes  forces  the 
wheels  to  turn,  and  communicates  motion  to  the  carriage. 

The  handspike  pawls  are  engaged  in  the  ratchet  of  the  truck- 
wheels  only  when  it  is  desired  to  give  motion  to  the  carriage; 
at  all  other  times  they  must  be  kept  clear  of  the  ratchets.  This 
is  accomplished  by  a  spring  catch  attached  to  each  one,  and  ma- 
nipulated by  Nos.  3  and  4  on  their  respective  sides.  To  prevent 
the  rear  truck-wheels  of  the  carriage  from  working  out  of  gear 
while  the  gun  is  being  run  Irom  battery,  or  jumping  in  gear 
when  the  gun  is  fired,  pawls  are  provided  lor  locking  the  rear 
axle.    The  elevation  is  given  by  means  ol  the  elevating  arc. 

With  a  well-instructed  detachment,  the  15-inch  gun  can  be 
fired  twelve  times  in  an  hour,  allowing  time  lor  deliberate  point- 
ing. 


128 


FLANK-CASEMATE   HOWITZER— SERVICE. 


The  carriage  and  chassis  for  the  front  and  centre  pintle  have 
the  same  dimensions,  viz.: 

Length  of  chassis 19  feet  7  inches. 

Width  of  chassis 5  feet  2  inches. 

Depth  of  chassis  rail 1  foot  8  inches. 

Length  of  carriage 8  feet  8  inches. 

Inclination  of  chassis  rails 3  degrees. 


Service  of  a  24-pounder  Howitzer  mounted  on  a 

flank-casemate  carriage. 

(Fig.  2,  Plate  8.) 

Description  of  Piece. 

309.  Howitzer,  cast-iron ;  smooth-bore ;  chambered ;  muz- 
zle-loader. 


Designation. 


Calibre 

Weight 

Preponderance 

Length  of  piece 

Length  of  bore  (in  calibres) 

Length  of  chamber 

Diameter  of  chamber 

Windage 

Charge  (cannon  powder) 

Shell  (empty) 

Weight  of  canister 

Carriage  (top  and  chassis),  wooden ;  without  re- 
coil checks - 


No. 

Lbs. 

Inch. 

5.8 

1475 

70 

69 

9.15 

2 
16 
20.5 

4.75 
4.62 
0.14 

Ranges  in  yards. 


Elevation. 


0« 
I© 
20 
3° 
5° 
5° 


(K 
C 

<y 
3(y 

0' 
30/ 


Case 

Shell. 

Shot. 

Time. 

295 

516 

•••••• 

600 

2* 

880 

3* 

1322 

1050 

4* 

Charge  2  Lbs. 


Canister  is  used  for  sweeping 
the  ditch  in  front  of  the  cur- 
tain ;  and  for  this  the  piece 
should  be  depressed  1  to  2 
degrees. 


The  piece  admits  of  7  degrees  elevation  and  9  degrees  depres- 
sion.   The  platform  is  a  permanent  part  of  the  work. 


PLANK-CASEMATE   HOWITZER — SERVICE.  129 

To  serve  the  piece. 

Four  men  are  necessaiy  :  one  ch icf-of-detach me nt,  one  gunner, 
and  two  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows  : 


Roller  handspike  (Iron)...  }  L^,,,%'*S""t  U"*  SC!"'P  WaI1,  b°" 


Leaning  against,  the  scarp  wall,  be- 

Sponge  and  rammer \      hind    No.    1 ;    the    rainincr-head 

upon  the  pavement. 

Containing  breech  sight,  chalk  and 
Gunner's  pouch \      chalk-line, and  priming-wire;  sus- 
pended from  knob  of  cascable. 

Cartridge-pouch Suspended  from  knob  of  cascable. 

Containing  primers  and   two  lan- 
Primer-pouch V      yards;   suspended  from  knob  of 


} 


1  Containing 
>■  yards ;  si 
J       cascable. 


Sponge-bucket Behind  and  near  No.  1. 

VtMit-cover Covering  the  vent. 

Tornpion In  the  muzzle. 

]   Containing  cartridges;  at  the  safest 

Bmlge-barrel V      and  most  convenient  place  near 

J        the  piece. 

When  several  pieces  are  served  together,  there  will  be  one 
worm,  one  ladle^  one  hammer-wrench ,  two  vent-punches^  two 
vent-gimlets,  and  one  gimner's  pincers  to  each  battery  of  not 
exceeding  six  pieces.  These  will  be  kept  in  the  filling-room  of 
the  service  magazine. 

The  rounds  of  canister  are  arranged  against  the  scarp  wall, 
behind  No.  2.  The  shells  are  at  the  filling-room  of  service  mag- 
azine, or  other  safe  position,  and  are  brought  as  required  to  the 
place  prescribed  for  the  budge-barrel.  They  are  strapped  to 
sabots.     The  fuse-plug  is  of  wood. 

To  cause  the  equipments  to  be  distributed. 

3lO.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  equips  himself  with  his  own  pouch ;  gives  the 
primer-pouch  to  No.  1  and  the  cartridge-pouch  to  No.  2 ;  takes 
off  the  vent-cover,  and  places  it  against  the  scarp  wall  beside 
the  canister;  applies  his  level  to  ascertain  the  highest  point  at 
the  breech  and  muzzle,  and,  with  the  assistance  of  No.  2,  snaps 

9 


130  FLANK-CASEMATE    HOWITZER — SERVICE. 

the  chalk-line  to  mark  the  line  of  metal;  clears  the  vent;  takes 
the  roller  handspike  in  the  right  hand,  and  resumes  his  post, 
holding  the  handspike  vertically  b}r  the  right  side,  its  lower  end 
on  the  pavement,  the  arm  extended  naturally. 

No.  1  equips  himself  with  the  primer-pouch.  No.  2  equips 
himself  with  the  cartridge-pouch,  which  he  wears  from  the  left 
shoulder  to  the  right  side. 

The  service  of  the  piece  is  executed  by  the  following  commands 
from  the  instructor  : 

1.  From  battery. 

311.  The  gunner,  embarring  in  the  left  mortise,  presses  the 
roller  under  the  rear  transom,  and,  holding  down  the  handspike* 
with  his  right  hand,  seizes  the  left  handle  with  the  left;  Nos.  1 
and  2  lay  hold  of  the  manoeuveriug  rings  and  handles. 

All  being  ready,  the  gunner  commands :  Heave,  and  the  car- 
riage is  run  to  the  rear  until  the  face  of  the  piece  is  about  one 
yard  from  the  wall,  when,  disengaging  the  roller,  he  commands 
Halt,  leaving  the  handspike  in  the  socket.  All  resume  their 
posts. 

1.  By  the  numbers,  2.  Load. 

312.  The  gunner  places  himself  at  the  breech;  breaks  to 
the  rear  with  the  right  foot;  closes  the  vent  with  the  second 
finger  of  the  right  hand,  and  manages  the  elevating  screw  with 
the  left. 

No.  2  removes  the  tompion  and  places  it  against  the  scarp,  near 
his  post. 

No.  1  seizes  the  sponge-staff  at  its  middle,  brings  it  across  his 
body,  plants  the  left  foot  opposite  the  muzzle,  close  to  the 
carriage,  and  breaks  off  with  the  right  foot;  at  the  same  time 
throwing  the  sponge-staff  into  the  left  hand,  back  down,  and 
extending  both  hands  towards  the  ends  of  the  staff,  enters  the 
rammer-head  into  the  embrasure,  introduces  the  sponge  into 
the  muzzle,  and  drops  the  left  hand  by  the  side.  He  then  forces 
the  sponge  to  the  bottom  of  the  chamber  with  three  motions,  at 
the  commands  TWO— three— FOUR. 

No.  2  goes  for  a  cartridge  and  returns  to  his  post.  If  shells 
are  used,  he  brings  a  shell  at  the  same  time. 

1.  Sponge. 

313.  No.  1,  using  both  hands,  backs  up.  sponges  the  cham- 
ber carefully,  withdraws  the  sponge,  pressing  it  against  the  lower 
surface  of  the  bore ;  turns  it  over,  stepping  to  his  left  for  this  pur- 
pose, and  rests  the  rammer-head  against  the  right  side  of  the 


J 


FLANK-CASEMATE   HOWITZER — SERVICE. 


131 


face  of  the  piece,  back  of  the  right  hand  down,  that  of  the  left 
up.  No.  2  introduces  the  cartridge.  No.  1  sets  it  home  by  the 
same  commands  and  motions  as  for  sponging. 

1.  Ram. 

314.  No.  1,  throwing  the  weight  of  his  body  on  the  staff, 
forces  the  cartridge  tightly  home  and  throws  out  the  rammer, 
holding  it  as  before,  the  rammer-head  against  the  right  side  of 
the  face  of  the  piece. 

No.  2  introduces  the  canister  or  shell,  and  resumes  his  post. 

No.  1  sets  the  canister  or  shell  home  with  care;  throws  out 
the  rammer,  replaces  it,  and  resumes  his  post. 

The  gunner,  rising  up,  pricks,  leaving  the  priming-wire  in  the 
vent,  and  resumes  his  post. 

1.   IN  BATTERY. 

315.  All  apply  themselves  to  the  carriage  as  prescribed  In 
par.  311,  and  ease  the  piece  into  battery.  As  soon  as  it  touches 
the  hurters,  the  gunner  commands :  Halt,  and  all  resume  their 
posts. 

1.  Aim. 

316.  No.  1  makes  ready  a  primer;  No.  2  goes  to  the  rear  of 
the  chassis,  and  takes  hold  of  it  to  traverse  it.  The  gunner  with- 
draws the  priming-wire;  aims  the  piece,  directing  No.  2  to  tra- 
verse it  to  the  right  or  left;  gives  the  command  Ready,  making 
a  signal  with  both  hands,  at  which  No.  2  resumes  his  post ;  takes 
with  him  the  roller  handspike  and  resumes  his  post.  No.  1  in- 
serts the  primer  in  the  vent  and  steps  back  obliquely  three  yards 
to  the  rear,  and  breaks  off  with  the  left  foot  to  his  left  and  rear. 

1.  Number  one  (or  the  like),  2.  Fire. 

317.  No.  1,  turning  his  face  from  the  piece,  pulls  the  lanyard 
and  fires  it ;  he  then  resumes  his  post. 

To  load  without  the  numbers,  and  to  fire. 

To  load  and  fire  continuously,  and  to  cease  firing. 

To  secure  the  piece. 

Executed  as  explained  for  the  siege  gun,  in  pars.  245,  246, 
and  247. 

Remarks. 

318.  In  repelling  assaults,  double  charges  of  canister  are 
used ;  the  charge  of  powder  remaining  the  same. 

The  effective  range  of  canister  is  not  over  four  hundred  yards. 


132  8-inch  rifle — service. 

Service  of  an  8-inch  Kifle  (converted). 

Description  of  gun. 
{Fig.  2,  Plate  3.) 

319.  This  piece  is  composed,  essentially,  of  two  parts:  the 
case,  f%  which  is  the  10-inch  smooth-bore  (described  in  par.  276) 
bored  up  to  a  diameter  of  13.5  inches,  and  a  lining4ube  of  coiled 
w  rough  t-i  ron. 

The  tube  consists  of  two  parts,  called,  respectively,  the  A  and 
B  tubes.  The  former  extends  the  entire  length  of  the  bore,  and 
contains  the  rifling;  the  latter,  or  B  tube,  is  shrunk  upon  the 
inner,  or  A  tube,  which  has  its  exterior  portion  cut  away  for  that 
purpose.  A  double  tube  is  thus  formed,  extending  32.75  inches 
from  the  rear  end.  The  two  tubes,  united  in  this  manner,  have 
the  same  exterior  diameter  throughout  the  entire  length,  and 
are  made  to  fit  accurately  the  bore  of  the  cast-iron  casing. 

The  bottom  of  the  tube  is  closed  with  a  wrought-iron  cup- 
shaped  plug,  p,  screwed  into  the  A  tube.  The  tube  is  inserted 
into  the  casing  from  the  muzzle,  and  is  secured  from  working 
out  by  a  muzzle-collar,  s,  screwed  in  at  the  face  of  the  piece ; 
and  from  turning  in  the  casing  by  a  steel  pin,  tf,  tapped  through 
the  casing  and  into  the  tube. 

A  shallow  and  narrow  gas-channel  is  cut  spirally  around  the 
exterior  of  the  reduced  portion  of  the  A  tube,  communicating 
with  star-grooves  cut  in  the  end  of  the  barrel,  and  with  the  gas- 
escape,  or  indicator,  bored  obliquely  through  the  breech  of  the 
casing  opposite  the  vent. 

Should  the  inner  tube  split,  under  the  action  of  firing,  the  fact 
would  be  indicated  by  the  escape  of  gas  through  this  hole,  and 
timely  warning  thus  be  given  of  the  injury  sustained  by  the  gun. 

The*  rifling  consists  of  fifteen  lands  and  grooves,  each  of  equal 
width,  viz.:  0.8377  inches.  Depth  of  grooves:  0.075  inches. 
Twist :  uniform,  one  turn  in  40  feet. 

There  is  no  chamber  proper  to  the  gun.  The  rifling  stops 
at  a  point  10  inches  from  the  bottom  of  the  bore,  the  diameter 
of  the  uurifled  portion  being  equal  to  that  of  the  rifled  portion 
across  lands. 

The  old  .vent  of  the  case  is  closed  by  a  wrought-iron  screw- 
plug,  and  2.75  inches  nearer  the  muzzle  a  new  one  is  bored  par- 
allel to  the  vertical  plane  through  the  axis  of  the  bore,  and  dis- 
tant therefrom  2.5  inches.  The  axis  qI  the  vent  enters  the  bore 
at  3.5  inches  from  the  bottom. 

Length  of  bore 117.25  inches. 

Weight  of  piece 16,100  pounds. 

Counter-preponderance 630  pounds. 


8-INCH   RIFLE — SERVICE. 


133 


The  counter-preponderance  is  corrected  by  an  eccentric  ring 
of  bronze  attached  to  each  trunnion. 

Weight  of  projectile  (average) 180  pounds. 

Weight  of  charge  (hexagonal  powder) 35  pounds. 

Initial  velocity 1.430  feet. 

Pressure  upon  square  inch  of  bore 33,000  pounds. 

Penetration  against  armor  at  1000  yards....  7.42  inches. 
Penetration  against  armor  at  1800  yard;*....  6.75  inches. 

Ranges. 

Charge :  35  pounds  hexagonal  powder. 


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134 


8-INCH   RIFLE — SERVICE. 


It  has  been  found  that  the  10-iuch  carriage,  upon  which  this 
piece  is  mounted,  is  not  sufficiently  stout  to  stand  many  dis- 
charges with  a  charge  of  35  pounds. 

Charges  of  25  pounds  will  penetrate  any  wooden  ship  at  or- 
dinary ranges,  but  are  of  no  effect  against  irou-clads.  The  car- 
riages will  stand  this  charge,  without  serious  damage. 

Ranges. 
Charge :  25  pounds  hexagonal  powder. 


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Length  of  cartridge  :  35  lbs.  =  24  inches;  25  lbs.  =  18  inches. 


8-INCII    ItlFLK — SKUVICK.  loO 

Nate. — The  carriages  upon  which  these  pieces  are  mounted 
are  those  altered  from  the  10-inch  barbette-gun  carriage,  and 
thus  far  are  only  experimental. 

Description  of  Carriage. 

{Plates  13,  14.) 

Distinguishing  features, 

320.  Carriages  Nos.  1  and  2  have  friction-hare  for  checking- 
recoil.  Nos.  3  and  4  have  hydraulic  cylinders  for  the  same  ob- 
ject. Nos.  3  and  4  have  a  geared  windlass,  with  cranks  and 
handles,  attached  to  the  rear  part  of  the  chassis.  Nos.  1  and  2 
are  without  windlass.  No.  1  is  distinguished  from  No.  2  by  the 
absence  of  the  ratchet-post,  and  by  having,  instead,  for  elevat- 
ing, a  circular  toothed  arc  operated  by  a  hand-wheel  and  pin- 
ions upon  the  left  cheek  of  the  carriage.  No.  2  has  the  ratchet- 
post,  but  no  toothed  arc. 

Carriage  No.  3  is  distinguished  from  No.  4  by  having  a  wedge- 
shaped  incline  bolted  to  the  top  of  each  rail  of  the  chassis,  near 
the  rear  end,  and  by  having  a  hand-lever  on  the  outside  of  each 
chassis  rail,  for  the  purpose  of  uncoupling  the  top-carriage  from 
the  chassis. 

Specific  features. 

Carriages  Nos.  1,  2,  and  4  have;  on  the  rear  part  of  the  top- 
carriage,  an  eccentric  axle,  with  truck-wheels.  No.  3  has,  in- 
stead, two  wheels  or  rollers,  each  having  its  own  eccentric  axle. 
In  none  are  the  front  axles  eccentric. 

For  checking  recoil  in  carriages  Nos.  1  and  2,  the  top-carriage 
is  supplied  with  a  box-clamp  having  two  friction-plates,  which 
act  upon  a  broad  wrought -iron  rail,  one-sixteenth  of  an  inch 
thicker  at  its  rear  than  at  its  front  end.  This  rail  is  attached  to 
the  chassis  in  front  by  a  transom  which  takes  the  place  of  the 
hurters;  and  fh  rear,  by  a  rod  and  rubber  spring  which  permits 
a  slight  play  to  prevent  buckling.  Rubber  counter-hurters  are 
secured  to  each  top-rail  of  the  chassis.  When  the  gun  is  run 
from  battery,  it  is  retained  in  that  position  by  means  of  the 
clamp;  by  relieving  the  pressure,  the  gun  runs  into  battery,  a 
slight  movement  of  the  compressor-bar  stopping  it  when  desired. 

The  piece  is  run  from  battery  in  the  same  manner  as  the  10- 
inch  smooth-bore,  except  that  with  carriage  No.  1  the  position 
of  the  elevating-wheel  renders  it  necessary  to  insert  the  left 
handspike  into  the  front  mortises  of  the  truck- wheel. 

To  check  recoil  in  carriages  Nos.  3  and  4,  an  hydraulic  buffer 
is  securely  placed  in  the  front  portion  of  the  chassis.    It  consists 


136  8-INCH    RIFLE— SERVICE. 

of  a  cast-iron  cylinder  78  inches  long,  with  an  interior  diameter 
of  8  inches,  closed  at  either  end  by  a  cast-iron  cap. 

Near  the  rear  end  of  the  top  of  the  cylinder  is  a  hole  for  the 
purpose  of  tilling  it  with  water,  or  some  non-freezing  liquid.  A 
hole  in  the  front  end.  closed  with  a  screw-plug,  permits  the  fluid 
to  be  withdrawn. 

Nine  and  one-half  gallons  (precisely)  of  fluid  are  required. 

A  wrought- iron  piston-rod  passes  through  the  rear  cap,  and  is 
secured  to  the  rear  of  the  top-carriage  by  a  wrought-iron  cross- 
head. 

The  piston-head,  of  wrought-iron,  0.25  inches  thick,  is  pierced 
near  its  circumference,  en  opposite  sides  of  the  rod,  with  two 
holes  seven-eighths  of  an  inch  in  diameter.  These  holes  flare 
out  both  ways  0.25  inches,  allowing  free  passage  to  the  fluid  from 
the  rear  to  the  front  of  the  piston,  permitting  the  top-carriage 
to  run  back  without  strain. 

Upon  the  top  of  the  rear  end  of  each  rail  of  the  chassis  of  No. 
3,  is  bolted  a  wedge  or  incline,  having  a  rise  of  2.5  inches  in  64 
inches;  near  the  rear  end  of  this,  is  attached  a  brass  angle- 
plate,  to  which  are  secured  three  rubber  counter- hurters.  A 
similar  angle-plate  with  hurters  is  attached  to  the  front  part  of 
the  chassis. 

Carriage  No.  4  is  likewise  provided  with  hurters  and  counter- 
hurters  of  rubber. 

The  top-carriage  of  No.  3  is  provided  with  two  sets  of  wheels 
or  rollers^  those  in  rear  having  eccentric  axles.  In  recoiling, 
the  carriage  starts  on  sliding  friction,  which  becomes  rolling  fric- 
tion when  it  accomplishes  part  of  the  rise,  the  ascent  absorbing 
a  considerable  portion  of  the  recoil.  To  prevent  the  carriage 
running  into  battery  after  striking  the  counter-hurters,  couplings 
are  attached  to  the  bottom  transom  of  the  top-carriage  and  to 
the  sides  of  the  chassis  rails ;  the  top-carriage  is  released,  and 
permitted  to  run  into  battery,  bjr  means  of  levers  on  the  outside 
of  the  chassis  rails.  • 

Attached  to  the  rear  end  of  the  chassis,  in  carriages  Nos.  3 
and  4,  is  a  geared  windlass,  for  the  purpose  of  drawing  the  gun 
from  battery. 

In  carriages  Nos.  1,  3,  and  4  the  gun  is  elevated  and  depressed 
by  means  of  circular  toothed  arcs,  to  which  motion  is  transmitted 
by  simple  multiplied  gearing  and  a  hand-wheel  on  the  left  side, 
of  the  carriage.     Carriage  No.  2  has  the  ordinary  ratchet-post. 

The  chassis  of  carriage  No.  3  is  provided  with  rollers,  resting 
on  the  pintle-plate,  instead  of  the  truck-wheels,  with  eccentric 
axle  of  the  ordinary  barbette  carriage.  The  rollers  are  without 
eccentric  axles. 


8-INCH   RIFLE — SERVICE.  137 

Flooring -boards  are  dispensed  with  in  carriage*  Nos.  3  and  4. 
A  step  is  placed  across  the  rear  notches  for  the  accommodation 
of  the  gunner  when  serving  vent  or  sighting. 

The  carriage  admits  of  28°  15'  elevation  and  12°  50'  depres- 
sion. 

Service  of  8-inch  Rifle. 

(Carriage  No.  1.) 

321*   Eight  men  are  necessary  :  one   chief-of-detachment, 

one  gunner,  and  six  cannoneers. 

The  implements  and  equipments  are  the  same,  and  are  ar- 
ranged in  the  same  manner,  as  for  the  10-iuch  smooth-bore  (par. 
277),  omitting  the  wheel-chocks  and  elevating-bar,  and  adding 
two  small  handspikes  (iron),  which  are  laid  on  the  steps  of  the 
chassis,  one  on  each  side  ;  one  compressor-bar,  standing  against 
the  parapet  near  No.  1 ;  and  blocks  and  fall  attached  to  crane. 

The  pouches  are  hanging  on  the  loft  eccentric  socket  of  top- 
carriage. 

The  powder,  primers,  and  fuses  are  in  the  service  magazine. 

The  shells  are  in  the  lilling-room  of  the  service  magazine,  and, 
prepared  for  firing,  are  brought  up  to  the1  piece  as  required. 

The  solid  projectiles  are  kept  piled  convenient  to  the  piece. 


To  distribute  the  implements  and  equipments. 

322.  Executed  as  in  par.  278,  except  that  No.  4,  instead  of 
mounting  upon  the  chassis,  takes  hold  of  the  handles  of  the 
hand-wheel  and,  by  direction  of  the  gunner,  adjusts  the  piece 
convenient^'  for  loading,  and  resumes  his  post. 

The  service  of  the  piece  is  executed  by  the  following  com- 
mands : 

1.  From  battery. 

323*   The  gunner  places  himself  two  paces  in  rear  of  the 
chassis,  and  commands:  1.  In-GEAR,  2.  Heave.    Nos.  3  and 
4,  at  the  first  command,  insert  the  small  handspike  in  the  ec- 
centric sockets  of  the  rear  wheels  of  the  top-carriage ;  No.  4 
unkeys  the  axle,  and  at  the  second  they  throw  the  wheels  in 
srear;  No.  4  keys  the  axle;  Nos.  3  and  4  replace  the  handspikes 
pon  the  steps,  and,  taking  the  truck  handspikes,  insert  them  in 
tie  sockets  of  the  truck-wheels;  No.  1,  meanwhile,  inserts  the 
ompressor-bar  in  one  of  the  holes  of  the?  compressor-screw,  and 
nclamps  the  friction-plates,  leaving  the  compressor-bar  in  the 
ole;  Nos.  3,  4,  5,  and  6  seize  the  truck  handspikes  with  both 
<inds  in  the  manner  prescribed  in  par.  279,  and  the  piece  is 


138  8-INCH    RIFLE — SERVICE. 

moved  from  battery  by  the  commands  and  means  specified  in 
the  same  paragraph,  except  that  Nos.  1  and  2  do  not  follow  np 
with  the  chocks,  but,  instead,  No.  1,  by  alternately  tightening 
and  slacking  the  compressor-screw,  retains  the  carriage  in  posi- 
tion as  it  is  run  back. 

When  the  muzzle  of  the  piece  is  about  one  yard  from  the  par- 
apet, the  gunner  commands:  1.  Halt,  2.  Out-of-gear,  3. 
Heave.  At  the  first  command,  Nos.  3  and  4  withdraw  their  hand- 
spikes and  replace  them  on  the  hooks;  at  the  second,  they  insert 
the  small  handspikes  in  the  eccentric  sockets;  and  at  the  third, 
throw  the  wheels  out  of  gear,  leaving  the  handspikes  in  the 
sockets.     All  resume  their  posts. 

1.  By  the  numbers ■,  2.  Load. 

324.  The  gunner  mounts  upon  the  chassis  and  closes  the  vent. 

No.  2  takes  out  the  tompion  and  places  it  by  the  parapet  near 
his  post. 

No.  1  turns  to  his  left,  steps  over  the  sponge  and  rammer ; 
faces  the  pieces;  takes  the  sponge-staff" in  both  hands,  the  backs 
down,  the  right  hand  three  feet  from  the  sponge-head,  the  left 
eighteen  inches  from  it;  returns  to  the  piece,  raising  the  staff" 
over  the  crest  of  the  parapet ;  places  the  left  foot  on  the  rail  of 
the  chassis,  the  other  in  the  most  convenient  position  on  the 
parapet,  or  on  a  step  placed  against  it  for  the  purpose,  and  in- 
serts the  sponge-head  into  the  muzzle ;  the  staff  in  prolonga- 
tion of  the  bore,  supported  by  the  right  hand,  the  right  arm 
extended,  the  left  hand  hanging  naturally  by  the  side. 

No.  2  takes  a  position  on  the  left  of  the  piece  corresponding' 
to  that  of  No.  1  on  the  right,  and  seizes  the  staff  with  the  left 
hand,  back  down,  near  to  and  outside  of  the  hand  of  No.  1. 

No.  3  faces  to  his  rear,  steps  over  the  rammer  and,  facing 
about,  seizes  the  staff  with  both  hands,  as  prescribed  for  No.  1 
with  the  sponge,  and  stands  ready  to  exchange  staves  with 
No.  1. 

No.  4  unkeys  the  crane,  takes  the  pass-box  to  the  rear  for  a 
cartridge,  and,  returning,  stations  himself  to  the  right  and  rear 
of  No.  2. 

No.  5,  taking  the  shell-hooks,  and  No.  6  the  carrying-bar,  go 
for  the  projectile;  No.  5  engages  the  shell-hooks  and  steadies 
them  while  No.  6  passes  the  bar  through  the  ring.  They  then 
cany  the  projectile,  No.  5  in  front  and  No.  6  in  rear,  and  place 
it  under  the  crane  conveniently  for  hoisting. 

No.  6  withdraws  the  bar  and  places  it  on  the  ground;  No.  5 
hooks  the  fall  into  the  ring  of  the  shell-hooks;  Nos.  5  and  6, 
working  upon  the  fall,  hoist  the  projectile. 


8-INCH   RIFLE — SERVICE.  189 

In  the  meanwhile,  Nos.  I  and  2  insert  the  sponge  in  the  bore 
by  the  following  motions,  at  the  commands  two — three— four — 
fioe — six  : 

Two.  They  insert  the  sponge  as  far  as  the  hand  of  No.  lt 
bodies  erect,  shoulders  square. 

Threk.  They  slide  their  hands  along  the  stall'  and  seize  it 
at  arm's-length. 

Four.     They  force  down  the  sponge  as  prescribed  for  two. 

Five.     They  repeat  what  is  prescribed  for  three. 

Six.  They  push  the  sponge  to  the  bottom  of  the  bore.  No. 
1  replaces  the  left  hand  on  the  stall',  back  up,  six  inches  nearer 
the  muzzle  than  the  right;  No.  2  places  the  right  hand,  back 
up,  between  the  hands  of  No.  1;  both  then  change  the  other 
hand  so  as  to  seize  the  staff,  back  up. 

1.  Sponge. 

325*  Nos.  1  and  2,  pressing  the  sponge  firmly  against  the 
bottom  of  the  bore,  turn  it  three  times  from  right  to  left  and 
three  times  from  left  to  right,  replace  the  hands  by  the  side,  and 
withdraw  the  sponge  by  similar  commands,  but  by  motions  con- 
trary to  those  for  inserting  it. 

No.  2  quits  the  staff  and,  turning  to  No.  4,  receives  from  him 
the  cartridge,  and  introduces  it  into  the  bore;  he  then  grasps 
the  rammer  in  the  manner  prescribed  for  the  sponge. • 

In  the  meanwhile,  No.  1,  turning  to  his  left,  passes  the  sponge- 
above  the  rammer  to  No.  3,  and,  receiving  the  rammer  from  No. 
3,  presents  it  as  prescribed  for  the  sponge,  except  that,  retaining 
hold  with  his  left  hand,  he  rests  the  rammer-head  against  the 
right  side  of  the  face  of  the  piece.  No.  3,  as  soon  as  the  sponge 
is  withdrawn,  passes  the  rammer  in  front  of  No.  1  onto  the  par- 
apet ;  receives  the  sponge  from  No.  1,  replaces  it  upon  the  prop,. 
and  resumes  his  post. 

No.  4,  setting  down  the  pass-box,  takes  out  the  cartridge  and 
hands  it  to  No.  2,  choke  to  the  front;  replaces  the  pass-box,  and 
goes  to  the  assistance  of  Nos.  5  and  6,  who  are  working  upon 
the  fall  hoisting  the  projectile;  No.  4  steadies  it;  Nos.  1  and  2: 
force  the  cartridge  home  by  the  same  commands  and  motions  as 
for  the  sponge. 

1.  Ham. 

826.  Nos.  1  and  2  slide  their  hands  along  the  staff  to  the 
'all  extent  of  their  arms,  and  press  the  cartridge  firmly  home; 
No.  2  quits  the  staff*  and  steps  slightly  to  one  side ;  No.  1  throws 
>ut  the  rammer  and  lays  it  upon  the  parapet;  No.  4,  as  soon  as 
So.  2  steps  aside,  swings  the  crane  so  as  to  bring  the  projectile 


140  8-INCH   RIFLE — SERVICE. 

directly  in  front  of  the  muzzle ;  Nos.  1  and  2  insert  it,  base  fore- 
most, into  the  bore;  No.  1  holds  it  while  No.  2  disengages  fc^e 
shell-hooks,  which  lie  hands  to  No.  5,  who  replaces  them  and 
resumes  his  post. 

Nbs.  4  and  6  overhaul  the  fall ;  No.  6  replaces  the  bar ;  No.  4 
secures  the  crane  and  fall,  and  both  resume  their  po?ts ;  Nos.  1 
and  2  force  the  projectile  home  by  commands  and  motions  simi- 
lar to  those  prescribed  for  the  cartridge,  pressing  it  firmljr  homo 
nt  the  command  Ram;  No.  2  quits  the  staff  and  resumes  his 
post;  No.  1  throws  out  the  rammer,  replaces  it  on  the  prop, 
and  resumes  his  post. 

The  gunner  pricks  the  cartridge,  leaving  the  priming-wire  in 
the  vent,  and  directs  No.  4  to  give  the  piece  an  elevation  of 
about  five  decrees. 

1.  In  battery. 

327.  The  gunner  commands:  1.  In-gear,  2.  Heave.     At 

the  first  command,  Nos.  3  and  4  seize  the  small  handspikes  and 
No.  1  the  compressor-bar;  No.  4  unkeys  the  axle,  and,  at  the 
second  command,  Nos.  3  and  4  throw  the  wheels  in  gear  and 
withdraw  their  handspikes ;  No.  1,  b.y  slacking  up  on  the  com- 
pressor-screw, then  permits  the  piece  to  run  gently  into  battery. 
As  soon  a*  the  carriage  is  against  the  hurters,  the  gunner  com- 
mands :  1-.  Out-of-gear,  2.  Heave.  Nos.  3  and  4  replace  the. 
handspikes  in  the  sockets,  and  at  the  command  heave  throw  the 
wheels  out  of  gear;  No.  4  keys  the  axle ;  both  replace  their 
liandspikes  on  the  steps;  No.  1  tightens  the  compressor  by  giv- 
ing the  bar  a  moderate  pull  (a  pull  of  about  20  lbs.);  withdraws 
the  bar,  returns  it  to  its  place  against  the  parapet,  and  all  the 
-cannoneers  resume  their  posts. 

1.  Aim. 

328.  The  gunner  commands:  1.  Chassis  in-gear,  2. 
Heave.  At  the  first  command,  Nos.  3  and  4  embar  in  the 
eccentric  sockets  of  the  chassis -wheels;  at  the  second  com- 
-inand,  assisted  bjr  Nos.  1  and  2,  they  throw  the  wheels  in  gear, 
and,  leaving  the  handspikes  in  the  sockets,  resume  their  posts. 
The  gunner  withdraws  the  priming- wire,  adjusts  the  breech 
sight,  and  gives  the  direction. 

In  the  meanwhile,  Nos.  5  and  6  embar  in  the  mortises  of  the 
rear  traverse-wheels,  and  move  the  trail  to  the  left  or  right  at 
the  command  Left  or  Right  by  the  gunner.  Nos.  1  and  2 
-assist  Nos.  5  and  6. 

The  proper  direction  being  given,  the  gunner  commands :  1. 
Chassis  out -op -gear,  2.  Heave.    At  the  first  command. 


8-INCH    RIFLE — SERVICE.  141 

Nos.  1  and  2  seize  the  handspikes;  at  the  second,  they  throw 
the  wheels  out  of  gear,  replace  the  handspikes  upon  the  hooks, 
and  resume  their  posts;  Nos.  5  and  0  unbar,  replace  tlu-ir  hand- 
spikes upon  the  hooks,  and  resume  their  posts;  No.  3  passes  the 
hook  of  the  lanyard  through  the  eye  of  a  primer,  holds  the  han- 
dle of  the  lanyard  with  the  right  hand,  the  hook  between  the 
thumb  and  forefinger,  and  stands  ready  to  hand  it  to  the  gun- 
ner; No.  i  seizes  the  handle  of  the  elevating-wheel  and.  by 
direction  of  the  gunner,  elevates  or  depresses  the  piece,  turning 
the  wheel  to  the  rear*  to  elevate,  and  to  the  front  to  depress. 
When  the  piece  is  correctly  aimed,  the  gunner  commands  : 
Ready,  makes  a  signal  with  both  hands,  remove*  the  sight, 
and,  receiving  the  primer  from  No.  3  with  his  right  hand,  in- 
serts it  into  the  vent,  dismounts  from  the  chassis,  and  goes 
where  he  can  best  observe  the  effect  of  the  shot;  Nos.  1  and  2 
break  off  sideways  with  the  foot  farthest  from  the  parapet;  No. 
3  steps  back  obliquely  three  yards  to  the  rear,  and  breaks  off  to 
his  left  and  rear  with  the  left  foot,  the  left  hand  hanging  natu- 
rally by  the  side,  the  lanyard  stretched ;  No.  4  resumes  his  post. 

1.  Number  one  (or  the  like),  2.  Fire. 

3*29.  No.  3,  turning  his  face  from  the  piece,  pulls  the  lanyard 
quickly,  but  steadily,  and  fires.  Immediately  after  the  discharge, 
Nos.  1,  2,  and  3  resume  the  erect  position ;  No.  3  rewinds  the 
lanyard  and  replaces  it  in  the  pouch.  The  gunner,  having  ob- 
served the  effect  of  the  shot,  returns  to  his  post. 

To  load  without  the  numbers,  and  to  fire. 
As  explained  in  par.  245. 

To  load  and  fire  continuously,  and  to  cease  firing. 
As  explained  in  pars.  246  and  247. 

To  secure  the  piece. 
As  explained  in  par.  249. 

To  replace  equipments, 

330*  As  explained  in  par.  250,  except  that  the  gunner  re- 
places the  pouches  on  the  left  eccentric  socket  of  the  top-carriage, 
tstead  of  on  the  knob  of  the  cascable. 

Service  of  the  8*inch  Rifle. 

{Carriage  No.  2.) 

331.   Carriage  No.  2  differs  from  No.  1  only  in  having  the 
dinary  ratchet-post,  instead  of  the  toothed  arc  and  hand-wheel, 


142  8-INCH   RIFLE — SERVICE. 

for  elevating  purposes.  Tlic  service  of  the  piece  with  it  differs 
from  that  of  No.  1  only  in  the  operation  of  elevating.  For  this 
purpose  an  elevating-bar  is  required,  and  is  used  as  explained  in 
pars.  278  and  284.   "(Service  of  the  10-inch  smooth-bore  gun.) 

Service  of  the  8-inch  Rifle. 

{Carriage  No.  3.) 

332.  Eight  men  are  necessary:  one  chief -of -detachment, 
one  gunner,  and  six  cannoneers. 

The  implements  and  equipments  are  arranged  as  follows  : 

Four  truck  handspikes....  \  Two  on  the  hooks,  and  two  on  the 
(iron)  J       steps  of  the  chassis. 

Two  small  handspikes....  \  On  the  steps  of  chassis;  one  on  each 
(iron)  j       side. 

One  yard  behind  the  cannoneers  of 

Sponge the  right ;  supported  upon  a  prop  ; 

Rammer "      heads  turned  from  the  parapet  and 

inclined  slightly  from  the  piece. 

Pass-box One  yard  in  rear  of  No.  4. 

I  Containing  friction-primers  and  htn- 

Primer-pouch  V     yard;  suspended  upon  the  left  ec- 

J      centric  socket  of  the  top-carriage. 

1  Containing  breech  sight  and  prim- 
z^liv  3r!?fdfuhp„o,L^e  left 
eccentric  socket  of  the  top -car- 
riage. 

Vent-cover Covering  the  vent. 

Muzzle-cover On  the  muzzle. 

1   Containing    cartridges;    at  a  safe 

Budge-barrel >      and  convenient   place  in  rear  of 

J       the  piece. 

Windlass-rope \  Woml(]  llP011  the  barrcl  of  the  wind- 

\       j  ass . 

Sponge-bucket Near  sponge. 

Shell-hooks Near  and  in  rear  of  No.  5. 

Canyiug-bar Near  and  in  rear  of  No.  6. 

Blocks  and  falls Attached  to  the  loading  crane. 

When  several  pieces  are  served  together,  there  will  be  one 
quadrant,  one  worm,  one  ladle,  one  kammcr-torencli*  two  vent- 
punches,  one  gunnels  pincers,  two  lanyards  ( extra ),  and  two 


8-INCH    RIFLE — SERVICE.  143 

vent-gimlets  to  each  battery  of  not  exceeding  six  pieces.     These 
are  kept  in  the  filling-room  of  the  service  magazine. 

The  shells  are  in  the  filling-room  of  the  service  magazine,  and 
are  brought  up  to  the  piece,  prepared  for  firing,  as  they  are  re- 
quired. The  powder  is  kept  in  the  service  magazine.  The  solid 
projectiles  are  kept  piled  convenient  to  the  piece. 

To  distribute  the  equipments. 

333.  The  instructor  commands : 

1.  Take  equipments. 

The  gunner  mounts  upon  the  step  of  the  toj>-carriage ;  takes 
off  the  vent  cover,  hands  it  to  No.  2  to  place  against  the  parapet 
in  rear  of  his  post;  gives  the  primer-pouch  to  No.  3;  equips 
himself  with  his  own  pouch;  clears  the  vent;  directs  No.  4  to 
adjust  the  piece  conveniently  for  loading,  and  resumes  his  post. 
No.  4  adjusts  the  piece  by  means  of  the  hand-wheel. 

The  service  of  the  piece  is  executed  by  the  following  commands  : 

1.  From  battery. 

334*  Nos.  5  and  6,  facing  to  the  front,  seize  the  crank- 
handles  with  both  hands  (the  hand  farthest  from  the  chassis  at 
the  end  of  the  handle ;  the  other  about  five  inches  from  it),  and 
unwind  the  rope;  the  gunner  attaches  the  hook  of  the  rope  to 
the  rear  of  the  carriage,  commands:  1.  In-oear,  2.  Heave, 
and  places  himself  in  rear  of  the  chassis.  At  the  first  command, 
Nos.  3  and  4  insert  the  small  handspikes  in  the  eccentric  sockets 
of  the  rear  wheels  of  the  top-carriage,  and  unkey  the  axles;  at 
the  second,  throw  the  wheels  in  gear,  key  the  axles,  replace  the 
handspikes  upon  the  steps,  and,  facing  to  the  rear,  grasp  the 
crank-handles  with  both  hands,  the  hand  farthest  from  the 
chassis  between  the  hands  of  Nos.  5  and  6. 

The  gunner  then  commands  :  Heave.  Nos.  3,  4,  5,  and  6, 
turning  the  crank,  run  the  gun  from  battery  until  the  couplings 
catch ;  Nos.  3  and  4 quit  the  crank-handles ;  Nos.  5  and  G  slightly 
unwind  the  rope  until  the  gunner  can  unhook  it.  The  gunner 
then  commands :  1.  Out-of-gear,  2.  Heave.  Nos.  3  and  4  in- 
sert the  small  handspikes  in  the  eccentric  sockets  and  throw  the 
vheels  out  of  gear,  and,  leaving  the  handspikes  in  the  sockets, 
Jl  resume  their  posts. 

Load — Sponge— R  am. 

335.  All  executed  identically  as  just  explained  for  carriage 
STo.l. 


144  8-INCH   RIFLE — SERVICE. 

1.  In  battery. 

336.  The  gunner  commands:  1.  In-gear,  2.  Heave.     At 

the  first  command,  Nos.  3  and  4  unkey  the  axles,  and  at  the 
second  command  throw  the  wheels  in  gear,  leaving  the  hand- 
spikes in  the  sockets;  at  the  same  time,  No«.  5  and  6  grasp  the 
coupling-levers  with  both  hands  and  at  the  command  Uncouple:, 
by  the  gunner,  let  the  piece  run  into  battery. 

The  gunner  then  commands:  1.  Out-of-gear,  2.  Heave; 
at  which  Nos.  3  and  4  throw  the  wheels  out  of  gear,  rekey  the 
axles,  replace  their  handspikes  on  the  steps,  and  all  the  cannon- 
eers resume  their  posts. 

1.  Aim. 

&f&1*  The  gunner  withdraws  the  priming-wire,  adjusts  the 
breech-sight,  and  gives  the  direction. 

Nos.  5  and  6,  assisted  by  Nos.  1  and  2,  embarring  in  the  mor- 
tises of  the  rear  traverse-wheels,  move  the  trail  to  the  left  or 
right  at  the  command  Left  or  Right  by  the  gunner.  At  the 
signal  from  the  gunner,  Nos.  5  and  6  unbar,  replace  their  hand- 
spikes on  the  steps,  and  resume  their  posts. 

No.  3  prepares  the  primer;  No.  4,  working  at  the  hand- wheel, 
elevates  the  piece ;  the  gunner  commands  :  Ready;  Nos.  1,  2, 
and  3  break  off, — all  as  just  explained  for  the  same  operation 
with  carriage  No.  1. 

1.  Number  one  (or  the  like),  2.  Fire. 
Executed  as  explained  for  carriage  No.  1. 

To  load  without  the  numbers,  and  to  fire* 
As  explained  in  par.  245. 

To  load  and  fire  contiTiuously,  and  to  cease  firing. 
As  explained  in  pars.  246  and  247. 

To  secure  the  piece. 
As  explained  in  par.  249. 

To  replace  equipments. 

As  explained  in  par.  250,  except  that  the  gunner  replaces 
the  pouches  on  the  carriage,  instead  of  on  the  knob  of  the  cas- 
cable. 

Service  of  8-inch  Rifle. 

(Carriage  No.  4.) 
338.  The  implements  and  equipments  for  this  carriage  are 


10-INCH   SIEGE   MORTAR — SERVICE.  145 

the  same  as  for  carriage  No.  3,  and  are  disposed  of  in  the  same 
manner.    The  number  of  men  is  likewise  the  same. 

1.  From  battery. 

339.  Nos.  5  and  6  apply  themselves  to  the  crank-handles ; 
the  gunner  attaches  the  hook  of  the  rope,  and  commands:  1. 
In-gear,  2.  Heave, — all  as  prescribed  for  carriage  No.  3. 

At  the  first  command,  Nos.  3  and  4  insert  the  small  hand- 
spikes in  the  eccentric  sockets  of  the  rear  wheels  of  the  top- 
carriage  ;  No.  4  unkeys  the  axle.  At  the  second  command,  Nos. 
3  and  4  throw  the  wheels  in  gear ;  No.  4  keys  the  axle ;  both 
replace  their  handspikes  on  the  steps  of  the  chassis,  and,  facing 
to  the  rear,  grasp  the  crank-handles  as  for  carriage  No.  3. 

The  gunner  then  commands:  Heave.  Nos.  3,  4,  5,  and  G, 
turning  the  cranks,  run  the  gun  from  battery  until  the  muzzle 
is  one  yard  from  the  epaulmcut.  The  gunner  commands :  1. 
Halt,  2.  Out-of-gear. 

Nos.  3  and  4  insert  the  small  handspikes  as  before  ;  No.  4  un- 
keys  the  axle,  and  at  the  second  command  the  wheels  are  thrown 
out  of  gear ;  the  handspikes  are  left  in  the  sockets.  Nos.  5  and 
6  then  unwind  the  rope  until  the  gunner  can  unhook  it,  and  all 
resume  their  posts. 

All  of  the  remaining  operations  are  executed  as  prescribed 
for  carriage  No.  1,  except  so  much  as,  In  No.  1,  relates  to  the 
compressor. 

Remarks. 

340.  1st.  Owing  to  the  fact  that,  in  all  of  the  foregoing  car- 
riages, the  steps  of  the  chassis  interfere  with  the  handspikes  when 
traversing  the  carriage,  each  piece  should,  in  addition,  be  pro- 
vided with  two  pinch-bars;  and,  for  the  purpose  of  holding  the 
traverse-wheels  securely  in  position  when  delicate  adjustments 
in  pointing  are  required,  two  wheei-chocks  (iron)  should  also  be 
furnished.  This  rule  is  general  for  all  pieces  having  traversing 
carriages. 

2d.  The  projectiles,  as  now  supplied,  are  not  furnished  with 
holes  for  the  shell-hooks.  To  remedy  this  defect,  a  rope  strap 
is  used,  instead  of  shell-hooks. 

Service  of  a  10-inch  Siege  Mortar. 

(Fig.  1,  Plate  9.) 

Description  of  Piece. 

341.  Mortar,  cast-iron ;  smooth-bore,  without  chamber. 

10 


146 


10-INCH  SIEGE   MORTAR — SERVICE. 


Number^  weights,  and  dimensions. 


Designation. 


Calibre 

Weight 

Preponderance 

Length  of  piece 

Length  of  bore 

Windage 

Charge  (maximum),  mortar  powder 

Weight  of  shell  (empty) 

Charge  to  fill  the  shell  (musket  powder) 

Charge  to  burst  the  shell  (musket  powder) 

Charge  to  blow  out  fuse  (musket  powder) 

Weight  of  carriage 

Weight  of  mortar-wagon 

Total  weight  of  mortar,  carriage,  mortar-wagon, 

and  implements 

Horses  to  transport 


No. 

Lbs. 

•  •••  ■  • 

1900 
00 

4 
90 

5 

2 

0.3 
1313 
3185 

8 

0600 

Inch. 


10 


28 

23.5 
0.13 


The  mortar  is  fired  from  a  wooden  platform.  (Par.  225.)  The 
carriage  is  of  wrought-iron,  and,  being  without  chassis,  rests 
directly  upon  the  platform. 

Ranges. 


Charge. 


Elevation. 


Lbs. 

0.5 

1.0 

1.5 

2.0 

2.5 

3.0 

3.5 

4.0 

0.5 

0.75 

1.0 

1.25 

1.5 

1.75 

2.0 

2.25 

2.5 

2.75 

3.0 

3.25 

3.5 

3.75 

4.0 

2.5 


Degrees. 

45 
45 
45 
45 
45 
45 
45 
45 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
60 
45 


Range,  Yards. 


Shell,  102  lbs.  Shell,  92  lbs 


217 

582 

1056 

1366 

1740 

1943 

2188 

2235 

140 

237 

545 

789 

939 

1072 

1189 

1337 

1459 

1582 

1667 

1732 

1780 

1935 

2085 


193 

554 

922 

1268 

1613 

1846 


Tons  of  Flight. 
Seconds. 


(  Shell,  00  MM. 

\      1530 


Shell,  102  lbs. 

6.92 
10.88 
15.00 
17.2 
19.2 
22.33 
22.00 
24.00 

7.16 

9.5 
15.0 
19.0 
19.0 
20.0 
20.4 
21.6 
23.5 
24.4 
25.4 
26.5 
27.2 
28.0 
29.0 


Shell,  92  lbs. 

6.33 
10.75 
14.9 
16.7 
18.0 
not  taken. 


\ 


•  ••••••»• 


••••••••• 


••••••••« 


Sb«U,  00  Uw. 

19.5 


I 


10-INCH   SIEGE   MORTAR — SERVICE. 


147 


Handspikes  (wood). 


Cartridge-pouch 
Primer-pouch.  ... 


Maximum  pressure  with  charge  of  four  pounds :  27,000  pounds 
pt-r  square  inch. 

To  serve  the  piece. 

342.  Six  men  are  necessary:  one  chief-of-detachtnent,  one 
gunner,  and  four  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 

Two  on  each  side,  lying  on  the  nia- 
nceuvering  holts ;  tlte  small  ends 
to  the  front  and  even  with  the 
front  of  the  cheeks. 

In  the  basket,  between  the  cheeks 
of  carriage,  in  rear. 

Containing  the  priming-wire,  fric- 
tion-primers, and  lanyard ;  in  the 
basket. 

Gnnnpr'a  noueh  \  Containing  the  gunner's  level,  chalk- 

fcunnei  s  pouch J     J|n^  ftnd  chftlk;  m  the  ^^ 

Wiper 

Quadrant 

Plummets  (3) 

Shell-hooks , 

Sleeves  (2  pair) 

Tompion In  the  muzzle. 

Sponge-bucket 

Wiper-stake 

Maul 

Broom 


} 
} 


In  the  basket. 


With  the  basket. 


on   the  carriage,  over  rear 
notches ;  handle  to  the  left. 


'g 


Elevating-bar  (iron) j  ^JJ 

Trestles  (3)  \  ^ear  tne  epaulment,  in  front  of  the 

To  each  battery  of  not  more  than  six  pieces  there  should  be 
one  hammer-wrench^  two  vent-punches^  one  gunner's  pincers,  two 
vent-gimlets^  and  two  lanyards  (extra). 
The  powder,  primers,  and  fuses  are  kept  in  the  service  mag- 
zin<\  and  the  shells,  when  filled,  in  the  filling-room  of  the 
lagazine.    To  prepare  the  ammunition,  there  will  be  required, 
t  the  magazine,  the  implements  specified  in  par.  275. 
The  charge  of  powder  is  varied  to  suit  the  required  distance, 
id  ghoul (1  be  carefully  weighed.    The  elevation  is  usually  con- 
ant,  and  45  degrees. 


148  10-INCH   SIEGE   MORTAR — SERVICE. 

The  plane  of  sight  is  established  by  plummets  :  one  suspended 
in  front  and  another  in  rear  of  the  mortar. 

A  convenient  method  of  suspending  the  plummets  is  by  means 
of  trestles,  made  light  and  easy  to  handle.  The  one  in  rear  of 
the  mortar  should  be  about  six  feet  high,  to  permit  the  gunner 
to  sight  without  stooping.  The  one  in  front,  being  on  the  par- 
apet, need  not  be  more  than  eighteen  inches  high.  They  should 
have  their  upper  edges  scored  with  fine  saw-cuts,  close  together, 
to  secure  the  plummets  when  adjusted  in  position. 

The  plummet-cord  should  be  of  fine  thread  or  silk,  and  if  affect- 
ed by  wind  when  suspended,  the  bob  should  swing  in  a  bucket 
of  water. 

A  third  trestle  and  plummet  is  required  temporarily  for  plac- 
ing the  first  two  in  position. 

To  establish  the  plummets  in  position,  the  instructor  com- 
mands : 

1.  Place  the  plummets. 
[Fig.  6,  Plate  16.) 

343.  The  gunner,  assisted  by  No.  2,  places  a  trestle  upon 
the  parapet  near  the  interior  crest,  and  suspends  from  it  a  pi  urn- 
met  in  such  position  that  it  will  be  approximately  in  the  line 
passing  through  the  centre  of  the  platform  and  the  object  to  be 
fired  at.  No.  3  brings  up  another  trestle,  which  the  gunner 
causes  him  to  place  a  few  feet  in  advance  of  the  first,  and  in  line 
with  it  and  the  object ;  sighting  by  the  plummet  first  establish- 
ed, he  causes  the  second  plummet  to  be  accurately  adjusted  on 
the  line  to  the  object;  then,  going  to  the  front  plummet  and 
sighting  back,  he  causes  No.  4  to  place  in  position  the  trestle  iti 
rear  of  the  mortar,  and  suspend  from  it  the  plummet,  being' 
careful  to  have  it  in  exact  line  with  the  two  on  the  parapet.  The 
front  trestle  is  then  removed  by  No.  3. 

The  trestle  in  rear  of  the  mortar  should  be  about  three  yards 
from  the  platform. 

No.  1,  meanwhile,  taking  the  maul  and  wiper-stake,  plants  the 
latter  in  the  ground  one  yard  in  rear  of  his  post,  and  leaves  the 
maul  on  the  ground  near  it.     All  resume  their  posts. 

Remarks. 

Should  the  fire  from  the  enemy  endanger  the  plummet  on  the 
parapet,  a  priming-wire  may  be  stuck  there  in  its  place  to  mark 
the  line. 

When,  owing  to  the  interposition  of  an  intermediate  obstacle, 
the  object  to  be  fired  at  cannot  be  seen  from  the  mortar,  a  point 
must  be  interpolated  on  the  required  line  in  such  position  that 


10-INCH   SIEGE   MORTAR— SERVICE.  149 

it  can  be  seen  from  the  mortar.  This  is  most  readily  effected  by 
using  Paddock's  interpolator,  a  simple  and  convenient  instru- 
ment, consisting  of  two  small  mirrors  attached  to  a  metallic 
frame.  One  of  Uhese,  termed  the  upper  mirror,  revolves  on  a 
horizontal  axis;  the  other  is  called  the  lower  mirror,  and  to  it  is 
attached  a  small  spirit-level,  a.  (Fig.  4,  Plate  15.)  Hair-lines 
are  marked  on  these  mirrors,  representing  the  trace  of  a  plane 
normal  to  the  axis  of  the  level  at  its  centre,  and  also  to  the  axis 
of  the  upper  mirror. 

To  use  the  instrument,  the  observer  places  himself  approxi- 
mately on  the  line  from  the  mortar  to  the  object  to  be  fired  at. 
Keeping  the  bubble  in  the  centre  of  the  level,  he  turns  the  in- 
strument so  that  the  mortar  will  be  reflected  from  the  upper 
mirror  onto  the  hair-line  of  the  lower  mirror.  He  then  revolves 
the  upper  mirror,  and,  catching  the  reflection  of  the  object,  ob- 
serves on  which  side  of  the  hair-line  of  the  lower  mirror  it  falls. 
He  moves  in  that  direction  until  both  images — that  of  the  mortar 
and  of  the  object — fall  upon  the  lower  hair-line,  the  two  hair- 
lines being  coincident.  A  pin  or  plummet  is  placed  in  prolonga- 
tion of  tliis  line  to  mark  the  required  point. 

To  make  the  last  part  of  the  observation  with  accuracy,  the 
instrument  should  be  rested  on  some  convenient  object. 

Wlien  the  foregoing  instrument  is  not  to  be  had,  a  point  may 
be  interpolated  by  two  persons,  each  using  a  light  slender  stake. 

They  place  themselves  as  near  as  practicable  on  the  required 
line,  one  facing  towards  the  mortar,  where  he  can  see  it,  and  the 
other  towards  the  object,  where  he  can  see  it,  and  both  within 
view  of  each  other. 

Holding  their  stakes  vertical,  they  sight  and  move  them  alter- 
nately, until  finally  they  have  them  in  such  position  that  they 
range  both  upon  the  mortar  and  the  object.  The  stakes  or,  bet- 
ter, plummets  are  then  adjusted  at  these  points,  and  sighting  by 
them  back  to  the  mortar,  a  plummet  is  suspended  in  the  usual 
manner  behind  the  platform.  The  plummets  thus  established 
mark  the  desired  plane  of  sight. 

This  operation  is  more  conveniently  performed  b}r  using  a  strip 
of  board,  ten  or  twelve  feet  long,  in  which  is  set  at  each  end 
a  printing-wire.  The  board  is  placed  at  the  intermediate  point 
n  a  position  approximately  in  the  plane  of  sight,  and  where  the 
nortar  can  be  seen  by  sighting  past  both  wires  back  upon  it,  and 
he  object  can  be  seen  by  sighting  forward  in  the  same  manner. 
.Vo  persons,  one  at  each  end,  by  alternately  sighting  and  mov- 
ng  the  board,  readily  establish  the  wires  in  the  required  line. 

i  plummet  is  then  suspended,  at  some  convenient  point  in  front 

f  the  mortar,  in  line  with  the  two  wires  on  the  board.    The 


150  10-INCH    SIEGE   MORTAR — SERVICE. 

plummet  in  rear  of  the  mortar  is  suspended  on  the  same  line. 
The  two  plummets  thus  established  determine  the  plane  of  sight* 

To  distribute  the  implements  and  equipments. 
344.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  goes  to  the  basket ;  gives  to  No.  1  the  broom,  the 
sponge-bucket,  the  wiper,  aud  a  pair  of  sleeves;  to  No.  3,  the 
primer  pouch  ;  to  No.  4,  the  cartridge-pouch ;  takes  himself  the 
gunner's  pouch  and  a  pair  of  sleeves,  and  gives  to  No.  2  the  bas- 
ket. The  gunner  equips  himself  with  his  pouch,  and,  assisted 
by  No.  4,  puts  on  his  sleeves. 

No.  1  hangs  the  wiper  upon  the  stake,  places  the  broom  and 
sponge- bucket  on  the  ground  by  the  side  of  it,  and,  assisted  by 
No.  3,  puts  on  his  sleeves. 

No.  2  places  the  basket  oue  yard  in  rear  of  his  post,  and  lays 
the  shell-hooks  on  the  ground  near  it. 

No.  3  equips  himself  with  the  primer-pouch,  assists  No.  1  in 
putting  on  the  sleeves,  and  clears  the  vent. 

No.  4  equips  himself  with  the  cartridge-pouch,  which  he  carries 
slung  from  the  left  shoulder  to  the  right  .side,  adjusts  the  piece 
to  about  45  degrees  elevation,  and  places  the  elevating-bar  on 
the  ground,  one  yard  in  rear  of  his  post  and  perpendicular  to 
the  platform. 

As  soon  as  the  gunner  has  put  on  his  sleeves,  he  applies  his 
level  and  -marks  the  highest  point  of  metal  at  the  muzzle  and 
near  the  vent ;  between  these  points,  assisted  by  No.  4,  he  snaps 
the  chalk-line,  thus  marking  the  line  of  metal.  The  cannoneers 
then  take  their  handspikes,  and  all  resume  their  posts.  The 
handspikes  are  held,  laid  down,  and  resumed  as  explained  in 
pars.  235  and  236. 

The  mortar  being  from  battery,  the  instructor  commands: 

1.  In  battery. 

345*  The  gunner  places  himself  two  yards  in  rear  of  the 
platform,  facing  the  piece;  Nos.  1,  2,  3,  and  4,  facing  towards 
the  epaulment,  embar ;  Nos.  1  and  2  under  the  front  nianoeuver- 
ing  bolts,  and  Nos.  3  and  4  under  those  in  rear,  engaging  the 
butts  of  their  handspikes  about  three  inches;  Nos.  1  and  3  hold 
the  small  end  of  their  handspikes  in  the  left  hand,  Nos.  2  aud  4 
theirs  in  their  right. 

All  being  ready,  the  gunner  commands  :  Heave,  aud  repeats 
it  as  often  as  maj'  be  necessary.  As  soon  as  the  piece  is  on  the 
middle  of  the  platform,  he  commands  :  Halt.  All  unbar,  and 
resume  their  posts. 


10-INCH    SIEGE   MORTAR — SERVICE.  151 

The  mortar  is  moved  to  the  rear  hy  the  command : 

1.  From  battery. 
Executed  by  inverse  means. 

1.  By  the  numbers,  2.  Load. 

346.  The  gunner  places  himself  one  yard  in  front  of  and 
facing  the  muzzle. 

No.  2  takes  out  the  tompion,  and  places  it  by  the*  epaulment 
in  rear  of  his  post. 

Nos.  1,  3,  and  4  lay  down  their  handspikes. 

No.  1,  turning  to  his  right,  takes  the  wiper  with  his  right  hand, 
turns  to  his  left,  and,  placing  himself  in  front  of  the  piece,  wipes 
out  the  bore,  sweeps,  if  necessary,  the  platform,  and  resumes  his 
post. 

No.  3,  as  soon  as  the  piece  is  wiped,  clears  the  vent  with  the 
priming-wire,  and  resumes  his  post  and  handspike. 

Nos.  2  and  4  go  for  the  cartridge  and  shell. 

No.  2  takes  with  him  his  handspike  and  the  shell-hooks,  and 
while  No.  4  is  getting  the  cartridge  inserts  the  shell-hooks  into 
the  ears  of  the  shell,  and  passes  the  handspike  through  the  ring. 
In  carrying  the  shell,  they  hold  the  handspike  iu  their  right 
hands,  No.  4  in  advance  and  at  the  small  end. 

Nos.  2  and  4,  passing  by  the  left  side  of  the  piece  and  between 
the  muzzle  and  the  gunner,  rest  the  shell  on  the  platform  against 
the  front  transom  of  the  carriage. 

The  gunner  receives  the  cartridge  from  No.  4,  aud,  stepping 
up  to  the  piece,  introduces  it  into  the  bore,  and  carefully  pours 
out  the  powder,  which  he  distributes  evenly  over  the  bottom  of 
the  bore ;  he  returns  the  cartridge-bag  to  No.  4,  who  places  it 
in  the  cart  ridge-pouch. 

Nos.  2  and  4  lift  the  shell  into  the  muzzle ;  the  gunner  steps 
forward,  and,  taking  hold  of  the  shell-hooks,  assists  in  lowering 
it  gently  into  its  place.  No.  2  then  withdraws  his  handspike 
from  the  ring,  and  Nos.  2  and  4  resume  their  posts.  The  gunner 
adjusts  the  shell  so  that  the  fuse  is  in  the  axis  of  the  piece,  dis- 
engages the  shell-hooks,  which  he  throws  to  their  place  behind 
No.  2,'  and  resumes  his  post. 

1.  Aim. 

347*  The  gunner  places  himself  behind  the  rear  plummet  to 
jive  the  direction,  and  commands:  Mortar  right;  Mor- 
\ar  left;  Muzzle  right;  Muzzle  left;  Trail  right; 
""bail  left,  a*  may  be  required. 


152  10-INCH    SIEGE    MORTAR — SERVICE. 

To  throw  the  mortar  to  the  right. 

No.  1  embars  under  the  right  front  manoeuvering  bolt,  from 
the  front;  No.  2  embars  under  the  left  front  notch;  No.  4  em- 
bars  under  the  right  rear  notch,  from  the  inside ;  both  of  these 
numbers  perpendicular  to  the  cheeks  of  the  carriage.  When  all 
are  ready,  the  gunner  commands:  Heave;  Steady.  The  can- 
noneers remain  embarred  until  he  gives  some  other  command, 
or  makes  a  signal  to  unbar. 

To  throw  the  mortar  to  the  left. 

No.  2  embars  under  the  left  front  manoeuvering  bolt,  from  the 
front;  No.  1  under  the  right  front  notch;  No.  3  under  the  left 
rear  notch,  from  the  inside. 

To  throw  the  muzzle  to  the  right. 

No.  1  embars  under  the  right  front  manoeuvering  bolt,  from 
the  front;  No.  2  embars  under  the  left  front  notch,  perpendicu- 
larly to  the  cheek. 

To  throw  the  muzzle  to  the  left. 

No.  2  embars  under  the  left  front  manoeuvering  bolt,  from 
the  front;  No.  1  under  the  right  front  notch,  perpendicularly  to 
the  cheek. 

To  throw  the  trail  to  the  right. 

No.  4  embars  perpendicularly  to  the  cheek  under  the  right 
rear  notch,  from  the  inside. 

To  throw  the  trail  to  the  left. 

No.  3  embars  perpendicularly  to  the  cheek  under  the  left  rear 
notch,  from  the  inside. 

In  all  of  these  operations  the  cannoneers  face  towards  the 
gunner  and  observe  his  signals. 

The  direction  having  been  given,  No.  4  embars  with  the  ele- 
vating-bar through  the  ratchet-post,  and  raises  or  depresses  the 
breech  at  the  command  of  the  gunner.  The  gunner  applies  the 
quadrant  to  the  face  of  the  piece,  giving  to  No.  4  the  command 
Raise,  or  Lower,  until  the  piece  is  at  the  required  elevation — 
usually  45  degrees — makes  a  signal  to  No.  4,  who  then  unbars, 
replaces  the  elevating-bar  on  the  ground,  and  resumes  his  post. 
The  gunner,  giving  the  command  Ready,  makes  a  signal  with 
both  hands,  returns  the  quadrant  to  the  basket,  and  goes  where 
he  can  best  observe  the  flight  of  the  shell. 

Nos.  1,  2,  and  4,  taking  their  handspikes  with  them,  go  four 


10-INCH   SIEGE   MORTAR — SERVICE.  153 

yards  in  rear  of  the  platform  and  face  to  the  front;  No.  4  be- 
tween Nos.  1  ami  2,  their  handspikes  held  erect  by  the  right  side, 
the  right  arm  extended  naturally. 

No.  3,  while  the  elevation  is  being  given,  pricks  the  vent, 
makes  ready  a  primer,  inserts  it  in  the  vent,  moves  three  yards 
obliquely  to  his  left  and  rear,  holds  the  lanyard  with  the  right 
hand,  the  cord  slightly  stretched,  back  of  the  hand  up,  and 
breaks  to  the  left  and  rear  a  full  pace  with  the  left  foot,  the  left 
hand  hanging  naturally  by  the  side. 

The  lanyard,  to  keep  the  primer  from  pulling  out  of  the  vent, 
should  be  passed  under  the  pipe  of  the  carriage. 

1.  Number  one  (or  the  like),  2.  Fire. 

348*  No.  3,  turning  his  face  from  the  piece,  pulls  the  lanyard 
quickly,  but  steadily,  and  fires. 

On  the  discharge  of  the  piece,  all  except  the  gunner  return, 
without  command,  to  their  posts.  As  soon  as  the  shell  strikes, 
the  gunner  returns  to  his  post. 

Previous  to  firing  the  piece,  any  mortar  near  the  one  to  be 
fired,  if  loaded  or  partly  loaded,  should  have  the  muzzle  closed 
with  the  tompion,  or  with  a  cloth  laid  over  the  face.  This  rule  is 
general. 

349.  When  exercising  for  instruction  only,  the  instructor 
continues  it  by  causing  the  piece  to  be  moved  toward  the  rear  of 
the  platform  by  the  command  FROM  battery.  He  then  com- 
mands : 

1.  Unload. 

350.  The  gunner,  receiving  the  shell-hooks  from  No.  2,  at- 
taches them  to  the  shell.  No.  2  passes  his  handspike  through 
the  ring  of  the  hooks  and,  assisted  bjr  No.  4,  raises  the  shell  from 
the  bore  of  the  piece  and  carries  it  to  its  former  place;  all  in  the 
inverse  order  in  which  it  was  brought  up.  The  gunner  and  Nos. 
3  and  4  resume  their  posts. 

351*  The  instructor  continues  the  series  of  exercises,  begin- 
ning with  in  battery. 

In  changing  posts.  No.  2  passes  by  the  front  of  the  piece.  This 
rule  is  general  for  all  mortars. 

To  load  without  the  numbers,  and  to  fire* 

To  load  and  fire  continuously* 

352.  Executed  as  in  pars.  245  and  246. 

To  cease  firing. 

Executed  as  in  par.  247. 


154  10-INCH   SIEGE   MORTAR — SERVICE. 

To  secure  piece  and  replace  equipments. 

353.  The  instructor  causes  the  piece  to  be  placed  on  the 
centre  of  the  platform,  and  commands: 

1.  Replace  equipments. 

All  replace  their  handspikes  on  the  manoeuvering  bolts ;  No. 
2  puts  in  the  tompion  and  replaces  the  basket  between  the 
cheeks,  in  rear;  No.  1  and  the  gunner  take  off  their  sleeves; 
the  gunner  receives  the  equipments  from  the  cannoneers  and 
replaces  them  in  the  basket;  Nos.  3  and  4  replace  the  trestles 
and  plummets. 

Remarks. 

354.  The  time  of  flight,  in  seconds,  for  siege-mortar  shells, 
at  an  elevation  of  45  degrees,  with  ordinary  charges,  Is  approxi- 
mately equal  to  one-fourth  the  square  root  of  the  range  in  feet. 

The  range  in  feet  is  approximately  equal  to  sixteen  times  the 
square  of  the  time  of  flight.  The  experimental  weight  of  charge 
and  length  of  fuse  required  may  be  obtained  from  the^e  rules. 

The  Boulongi  telemeter  is  used  in  determining  the  distance  at 
which  a  shell  bursts;  or  this  distance  may  be  ascertained  by 
multiplying  the  number  of  seconds  which  elapse  between  see- 
ing the  flash  and  hearing  the  report  of  the  shell  by  1100;  the 
product  will  be  approximately  the  distance  in  feet. 

Fire  and  UgJit  balls,  according  to  their  size,  are  fired  from 
mortars  of  corresponding  calibres.  With  a  charge  of  one  twen- 
ty-fifth of  its  weight,  the  ball  is  thrown  from  six  hundred  to 
seven  hundred  yards.  Shells  for  mortars  are  fired  without 
sabots. 

Siege  mortars  can  be  fired  conveniently  at  the  rate  of  twelve 
rounds  an  hour,  but  in  case  of  need  they  may  be  fired  with 
greater  rapidity. 

To  prepare  the  mortar  for  transportation,  see  par.  466. 

It  is  preferable  to  weigh  the  powder  instead  of  measuring  it, 
as  bjr  so  doing  more  uniform  results  are  obtained.  For  this 
purpose  a  pair  of  brass  counter-scales  are  required  at  the  maga- 
zine, in  place  of  the  prescribed  set  of  powder-measures.  The 
quantity  of  powder  which  a  measure  will  contain  is  consider- 
ably increased  by  tapping  and  settling  it;  therefore,  to  obtain 
uniform  results  when  the  powder  is  measured,  all  the  charges 
for  any  series  of  firings  should  be  either  settled  or  unsettled. 

Every  mortar  should  have  the  line  of  metal  permanently 
marked  on  it;  in  which  case  all,  in  the  foregoing  and  following, 
that  relates  to  marking  the  line  of  metal  with  chalk  will  be 
omitted. 


8-INCH    SIEGE    MORTAR — SERVICE. 


155 


Service  of  an  8-inch  Siege  Mortab. 
Description  op  Piece. 
355.  Mortar,  cast-iron ;  smooth-bore,  without  chamber. 
Number,  weights,  and  dimensions. 


Designation. 


Calibre 

Weight 

l*reponderance 

Length  of  piece 

Length  of  bore  (calibres) 

Windage 

Charge  (maximum),  mortar  powder 

Weight  of  shell  (empty) 

Charge  to  fill  shell,  musket  powder - «.. 

Charge  to  blow  out  fuse-plug 

Weight  of  carriage 

Wright  of  carriage,  mortar,  and  implements. 

(One  mortar- wagon  will  carry  three  mortars, 

with  their  carriages.) 
Horses  required  for  above ....... 

Ranges. 


No. 

Lbs. 

— 
Inch. 

8 

•••»•« 

1010 

•••••• 

« •  ■  • 

00 

22 

2 

2.25 
46 

0.12 

2.5 

0.25 

900 

1965 

8 

Charge. 

Elevation. 

Range,  Yards. 

Time  op  Flight. 
Seconds. 

Ounces. 

Degrees. 

Shell,  52  lbs. 

Shell,  46  lbs. 

Shell,  52  lbs. 

Shell,  46  lbs. 

8 

45 

399 

433 

9.50 

9.65 

12 

45 

717 

727 

12.45 

12.50 

10 

45 

955 

1029 

14.85 

15 

14 

45 

1265 

1275 

16.50 

16.80 

The  piece  is  fired  from  a  wooden  platform.    {Par.  225.) 

To  serve  the  piece. 

Four  men  are  necessary :  one  chief-of-dctachment,  one  gun- 
ner, and  two  cannoneers. 
The  implements  and  equipments — omitting  two  handspikes- 
ncl  adding  a  grummet-wad — are  the  same  as  for  the  10-inch 
lege  mortar,  and   are  arranged   in   the  same  manner.     The- 
nimmet-wad  is  in  the  basket. 

356.    The  service  of  the  piece  is  the  same  as  that  prescribed 
>r  the  10-inch  siege  mortar,  with  the  following  modifications : 


156  8-INCH   SIEGE   MORTAR — SERVICE. 

At  the  command  take  equipments \  No.  1  performs  the  duties 
•of  No.  3,  and  No.  2  those  of  No.  4,  in  addition  to  their  own. 
No.  2  places  the  grummet-wad  on  the  platform  in  front  of  the 
•carriage,  near  the  transom,  and  assists  No.  1  to  put  on  his 
sleeves. 

At  the  command  in  battery,  Nos.  1  and  2  embar  under  the 
front  manoeuvering  bolts,  facing  to  the  front. 

At  the  command  from  battery.  No.  1  embars  under  the  right 
front  manoeuvering  bolt,  and  No.  2  under  the  left  rear  bolt, 
both  facing  from  the  parapet.  If  the  carriage  has  no  rear 
manoeuvering  bolts,  No.  2  embars  under  the  left  rear  notch, 
nearly  perpendicular  to  the  cheek. 

In  loading,  No.  1,  having  wiped  out  the  piece,  clears  the  vent 
and,  if  necessary,  sweeps  the  platform. 

No.  2,  laying  down  his  handspike  and  taking  with  him  the 
shell-hooks,  goes  for  a  cartridge  and  shell,  returns  by  the  left  of 
the  piece,  passes  between  the  gunner  and  the  muzzle,  and,  rest- 
ing the  shell  upon  the  wad,  gives  the  cartridge  to  the  gunner. 

The  gunner,  having  poured  in  the  powder,  returns  the  car- 
tridge-bag to  No.  2,  and  distributes  the  powder  evenly  over  the 
bottom  of  the  bore ;  takes  from  No.  2  the  shell-hooks,  raises  the 
shell  and  lowers  it  into  its  place  in  the  bore.  All  resume  their 
posts. 

At  the  command  Aim,  the  gunner  performs  the  same  duties 
and  gives  the  same  commands  as  with  the  10-inch  mortar.  (Par. 
347.) 

For  mortar  right :  No.  1  embars  perpendicularly  to  the  cheek 
under  the  right  front  notch,  from  within,  and  No.  2  similarly 
under  the  left  rear  notch,  from  without. 

For  mortar  left :  No.  2  embars  perpendicularly  to  the  cheek 
under  the  left  front  notch,  from  within,  and  No.  1  similarly  un- 
•der  the  right  rear  notch,  from  without. 

For  muzzle  right :  The  same  as  for  the  10-inch  mortar.  (Par. 
347.) 

For  muzzle  left:  The  same  as  for  the  10-inch  mortar.  (Par. 
347.) 

For  trail  right:  No.  2  embars  perpendicularly  to  the  cheek 
under  the  right  rear  notch,  from  the  inside. 

For  trail  left:  No.  1  embars  perpendicularly  to  the  cheek  un- 
der the  left  rear  notch,  from  the  inside. 

In  all  of  these  operations  Nos.  1  and  2  face  towards  the  gunner 
and  observe  his  signals. 

The  direction  being  given,  the  elevation  is  given  as  prescribed 
for  the  10-inch  mortar  (par.  347),  except  that  No.  2  performs  the 
•duties  therein  prescribed  for  No.  4,  and  No.  1  those  for  No.  3. 


COEHORN   MORTAR — SERVICE. 


157 


At  the  signal  from  the  gunner,  No.  1  prepares  to  Are  as  pre- 
scribed for  No.  3  in  the  exercises  for  the  10-inch  mortar.    (Par. 

347.) 

Service  of  a  Coehorn  Mortar, 

(Fig.  2,  Plate  9.) 
Description  op  Piece. 

357.  Mortar,  bronze;  bore,  smooth,  with  chamber;  calibre, 
5.8  inches;  weight  of  piece,  164  lbs. ;  extreme  length,  1G.32  inches; 
maximum  charge,  12  oz.  "mortar  powder" ;  weight  of  shell, 
empty,  16.8  lbs. ;  charge  to  Jill  the  shell,  1  lb. ;  to  blow  out  fuse* 
2oz. 

The  carriage  is  simply  a  block  of  wood,  weighing  132  lbs.; 
total  weight  of  piece,  equipments,  and  carriage,  311  lbs. 

Ranges* 


Charge. 

Elevation. 

Projectile 
weighing 

17.5  LBS. 

Tike  of 
Flight. 

Ounces. 

Degrees. 

Yards. 

Seconds. 

2.0 

45 

84 

4.0 

45 

261 

5.0 

45 

425 

6.0 

45 

54S 

6.5 

45 

666 

7.0 

45 

840 

7.5 

45 

980 

8.0 

45 

8.5 

45 

1074 

9.0 

45 

9.5 

45 

10.0 

45 

1262 

10.5 

45 

11.0 

45 

i*316 

12.0 

45 

1385 

The  carriage  or  block  upon  which  the  Coehorn  mortar  is 
mounted,  is  provided  with  two  handles  on  each  side,  by  means 
of  which  the  mortar  is  readily  carried  by  four  men  from  one  part 


158  COEHORN  MORTAR — SERVICE. 

of  the  work  to  another.     They  accompany  troops  in  the  field  for 
use  against  tin  enemy  covered  by  intrenchments. 

The  ground,  when  firm,  is  sufficient  for  the  carriage  to  rest 
upon  ;  if  it  is  not  firm,  a  platform  can  readily  be  extemporized 
from  such  material  as  may  be  at  hand.  The  carriage  should  be 
level  when  the  mortar  is  fired. 

To  serve  the  piece. 

35  S.  Four  men  are  necessary  :  one  chief-of-detachment,  one 
gunner,  and  two  cannoneers. 

The  implements  and  equipments  are  carried  in  a  basket,  which 
is  near  and  in  rear  of  the  mortar.  They  are  as  follows :  Primer- 
pouch,  containing  priming-wire,  primers,  and  lanyard;  gunner's 
pouch,  containing  gunner's  level  and  a  pair  of  small  pincers;  one 
quadrant,  one  sponge,  one  plummet,  and  one  mallet.  A  small 
wedge  is  used  as  a  quoin. 

The  mortar  should  have  a  permanent  line  of  metal  marked 
upon  it ;  otherwise  this  must  be  marked  as  for  the  10-inch  siege 
mortar.     {Par.  344.) 

The  shells  should  be  strapped  with  tin,  and  be  provided  with 
«ord  handle.  They,  together  with  the  powder  and  fuses,  are 
kept  in  the  service  magazine. 

The  implements  for  preparing  ammunition  are  the  same  as 
prescribed  in  par.  275. 

The  service  of  the  piece  is  analogous  to  that  for  the  10-inch 
siege  mortar.    (Par.  342  and  following.) 

Remarks. 

359.  When  Coehorn  mortars  accompany  troops  in  cam- 
paign, they  may  be  carried  on  ordinary  field  caissons;  each  cais- 
son carrying  one  mortar,  together  with  sixty  rounds  of  ammuni- 
tion. 

The  mortar  is  carried  on  the  caisson  body,  the  front  chest  being 
removed  for  this  purpose.  The  piece  is  securely  lashed  with 
ropes  through  the  handles.  The  remaining  ammunition  chests 
are  arranged  to  carry  thirty  shells  each.  The  powder  is  in  cans, 
and  a  set  of  measures  (from  one  to  six  ounces)  should  be  pro- 
vided. The  shells  should  be  charged  and  the  fuse-plugs  driven, 
ready  for  the  insertion  of  the  fuses. 

A  caisson  with  chests  similarly  arranged  should  accompany 
each  piece. 

The  mortars  may  also  be  carried  in  ordinary  army  transporta- 
tion-wagons. Each  \va«rou  will  carry  one  Coehorn  and  its 
equipments  (weighing  311  pounds),  and  sixteen  boxes,  each 
containing  eight  shells  and  weighing  168=2G88  pounds — total, 
2999  pouuds :  a  fair  load,  on  good  roads,  for  four  horses  or  six 
nudes. 


13-INCH   MORTAR — SERVICE. 


159 


Battery  op  Six  Coehorns. 

One  captain,  three  lieutenants,  six  sergeants,  six  corporals, 
eight  drivers,  thirty  cannoneer?,  and  thirty-two  horses. 

When  ordinary  wagons  are  used  instead  of  caissons,  two  one- 
horse  carts  are  allowed  as  tenders  in  bringing  up  ammunition,  &c. 

An  army  operating  in  the  Held  should  be  abundantly  supplied 
with  this  handy  and  useful  weapon. 

Service  of  a  13-inch  Mortar  (eccentric  axle). 

{Fig.  4,  Plate  9.) 
Description  op  Piece. 
360.  Mortar,  cast-iron  ;  smooth-bore,  without  chamber. 


Designation. 


L.B8. 


Weight  of  piece - » |  17,120 

Preponderance 

Extreme  length 

Length  of  bore 

Windage 

Charge  (maximum),  mortar  powder 

Weight  of  shell  (empty) 

Charge  to  fill  shell ~ 

Charge  to  blow  out  fuse-plug 

Weight  of  carriage 


Xf,X*V 

00 

54.5 

85.1 

0.13 

20 

216 

11 

0.3 

4,140 

Inch. 


The  mortar  is  fired  from  a  wooden  platform.  (Par.  227.)  The 
carriage  is  of  wrought-iron,  and,  being  without  chassis,  rests  di- 
rectly upon  the  platform. 

An  axle,  carrying  at  each  extremity  a  truck-wheel,  passes 
through  the  carriage  near  the  front  end ;  this  axle  is  eccentric, 
and  when  thrown  in  gear  the  truck-wheels  rest  upon  the  plat- 
form ;  only  the  rear  part  of  the  shoe  then  rests  on  the  platform 
and  moves  with  sliding  friction.  Two  steps  are  placed  on  the 
front  part  of  the  carriage  for  convenience  in  loading. 

Manges. 


Char  ok. 


Lbs. 

10 
10 
15 
20 
10 
15 
20 


Elevation. 

Range. 

Degrees. 

Yards. 

30 

2875 

45 

318T 

45 

3759 

45 

4636 

60 

2852 

60 

3378 

60 

3893 

Time  op 
Flight. 


Seconds. 

19 

25.8 

28 

31.75 

82.75 

36.75 

39.16 


160  13-INCH    MORTAR — SERVICE. 

To  serve  the  piece. 

361.  Eight  men  are  necessary  :  one  chief-of-detachment,  one 
gunner,  and  six  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows : 

Truck  handspikes  (Iron)  -  }  ^tte  clleekt'  *"**"*  **  *'"** 


Maneuvering  handspikes, 
(wood.) 


One  on  each  side,  lying  on  plat- 
form against  the  cheeks,  small 
ends  to  the  front  and  resting  on 
the  truck-wheels. 


Elevatincr-har  rironY  1  L^in^  on   the   carriaSe>  ove1'   rear 

J^ievatmg-Dar  (iron; J      notches,  handle  to  the  left. 

Wheel-chocks  (iron) }  °n0ef  on  ^  side'  on  the  u^er  ste*> 


On  prop,  one  yard  in  rear  of  No.  1 ; 

Sponge  y     sponge -head  towards  the  epaul- 

meut. 

Pass-box One  yard  behind  No.  4. 

Quadrant 1 

piSmmeiyythre^:::::.:::::;  I  inf^ket:  b*tween  the  cheeks  °* 

Sleeves  (two  pair) !.  I       tbe  cama«e'  m  rear' 

Shell-hooks J 

Tompion In  the  muzzle. 

Containing  the  priming-wire,  fric- 
Primer-pouch }■      tion-primers,  and  lanyard ;  in  bas- 
ket. 

level,   chalk 


} 

Gunner's  Douch  \  Containing   gunner's    level, 

trunnei  s  poucn j      ftnd  chalk.llne .  in  Dasket, 

} 


Sponge-bucket 

Broom J-  With  basket. 

Carrying-bar  (iron) , 

Trestles  (three) Near  epaulmcnt,  in  front  of  piece. 

To  each  batter}'  not  exceeding  six  pieces  there  will  be  one 
hammer-wrench,  two  vent -punches,  one  gunner's  pincers,  two 
lanyards  (extra),  and  two  vent-gimlets.  These  are  kept  in  the 
filling-room  of  the  service  magazine. 

The  powder,  primers,  and  fuses  are  kept  in  the  service  maga- 
zine, and  the  shells  in  the  filling-room  of  the  magazine. 

The  implements  for  preparing  the  ammunition  are  those  speci- 
fied in  par.  275. 


13-INCH   MORTAR — SERVICE.  161 

To  establish  the  plummets  in  the  plane  of  sight,  the  instructor 
commands :  Plage  the  plummets.  Executed  as  for  the  10- 
inch  siege  mortar.     (Par.  343.) 

To  distribute  the  implements  and  equipments. 

36£.  The  instructor  commands  : 

1.  Take  equipments. 

The  gunner  goes  to  the  basket ;  gives  to  No.  1  the  broom,  the 
sponge-bucket,  and  a  pair  of  sleeves ;  to  No.  3,  the  primer-pouch, 
and  to  No.  2  the  carrying-bar  and  basket.  No.  1  places  the 
broom  and  bucket  on  the  ground  in  his  rear,  and,  assisted  by 
No.  3,  puts  on  a  pair  of  sleeves. 

The  gunner  equips  himself  with  his  pouch  and,  assisted  by 
No.  4,  puts  on  a  pair  of  sleeves;  then,  applying  his  level,  ascer- 
tains and  marks  the  highest  points  of  metal  at  the  muzzle  and 
near  the  vent.  Between  these  points,  assisted  by  No.  4,  he 
snaps  the  chalk-line,  thus  marking  the  line  of  metal ;  he  then 
resumes  his  post. 

No.  2  places  the  basket  one  yard  behind  him.  and  lays  the 
carrying-bar  and  shell-hooks  on  the  ground  near  it;  No.  3 
eqnips  himself  with  the  primer-pouch  and  clears  the  vent ;  No. 
4  places  the  elevating-bar  behind  him  and  perpendicular  to  the 
carriage;  Nos.  5  and  0  place  each  a  maneuvering  handspike  on 
the  ground  perpendicular  to  the  carriage,  the  small  end  resting 
on  the  edge  of  the  platform  and  on  the  side  of  them  next  the 
epaulment. 

The  truck  handspikes,  when  not  in  use,  remain  on  the  hooks. 

The  mortar  being  from  battery. 

363.   The  instructor  commands : 

1.  In  battery. 

The  gunner  places  himself  two  yards  in  rear  of  the  platform, 
facing  to  the  piece,  and  commauds :  In-qear.  Nos.  3  and  4 
take  the  truck  handspikes  from  the  hooks  and  embar  in  the 
eccentric  sockets ;  Nos.  5  arid  G  seize  the  handspikes  above  the 
hands  of  Nos.  3  and  4.  The  gunner  commands  :  Heave  and, 
'is  soon  as  the  wheels  are  in  gear,  Embar,  when  the  handspikes 
ire  placed  in  the  most  convenient  rear  mortises  of  the  truck- 
wheels.  The  mortar  is  moved  to  l  he  front  as  far  as  required  by 
the  alternate  commands  heave  and  embar  f rom  the  gunner;  he 
then  commands :  Halt  and  Out-of-qkar,  and  the  handspikes 
\re  again  inserted  in  the  eccentric  sockets.     The  gunner  com- 

11 


162  13-INCH   MORTAR — SERVICE. 

mands :  Heave,  the  wheels  are  thrown  out  of  gear,  and  the 
handspikes  returned  to  their  hooks.  Nos.  3,  4,  5,  and  6  then  re- 
sume their  posts. 

1.  From  battery. 

Executed  as  above,  except  that  the  truck  handspikes  are  in- 
serted in  the  most  convenient  front  mortises  of  the  truck-wheels 
at  the  command  embar. 

1.  By  the  numbers,  2.  Load. 

364.  No.  2  takes  out  the  tompion  and  places  it  by  the  epaul- 
ment  in  rear  of  his  post.  The  gunner  places  himself  one  yard 
in  front  of  the  piece,  facing  the  muzzle. 

No.  1,  facing  to  his  right,  takes  the  sponge-staff  in  his  right 
hand,  mounts  upon  the  step,  and  passes  the  sponge  to  the  bottom 
of  the  bore;  sponges  with  both  hands,  withdraws  the  sponge, 
replaces  it  on  the  prop,  and  resumes  his  post;  No.  3  clears  the 
vent;  No.  4,  taking  the  pass-box,  goes  for  a  cartridge ;  Nos.  2, 
3,  5,  and  6  go  for  the  shell ;  No.  2  takes  with  him  the  carrying- 
bar  and  shell-hooks,  engages  the  shell-hooks  in  the  ears  of  the 
shell,  and  passes  the  carrying-bar  through  the  ring. 

In  carrying  the  shell,  Nos.  3  and  5  are  in  advance,  and  Nos.  2 
and  6  in  rear;  Nos.  2  and  3  are  at  the  ends  of  the  bar,  using 
their  right  hands;  Nos.  5  and  6  use  their  left  hands.  The  shell 
is  brought  up  by  the  left  side  of  the  piece,  and  those  carrying  it, 
passing  between  the  gunner  and  the  muzzle,  rest  it  on  the  step ; 
No.  4  hands  the  cartridge  to  the  gunner,  who  pours  the  powder 
into  the  piece,  and,  using  the  spatula,  distributes  it  evenly  over 
the  bottom  of  the  bore ;  he  then  returns  the  cartridge-bag  to 
No.  4,  who,  putting  it  in  the  pass-box,  resumes  his  post. 

The  shell  is  raised  by  the  numbers  at  the  carrjring-bar,  awl 
lowered  into  the  bore  until  the  bar  rests  against  the  face  of  the 
piece.  The  gunner  seizes  the  shell-hooks,  and,  after.No.  2  with- 
draws the  bar,  lowers  the  shell  into  its  place,  adjusting  it  so 
that  the  fuse  will  be  in  the  axis  of  the  piece ;  disengages  the 
shell-hooks,  which  he  throws  behind  No.  2,  and  then  resumes 
his  post.  No.  2  replaces  the  carrying-bar  on  the  ground,  and 
resumes  his  post. 

When  necessary,  the  platform  will  be  swept  by  No.  1. 

1.  Aim. 

365.  The  gunner  places  himself  behind  the  rear  plummet  to 
give  the  direction,  and  commands :  In-gear — Heave— Em- 
bar.    All  executed  as  prescribed  in  par.  363. 

The  gunner  then,  sighting  by  the  plummets,  gives  the  direc- 


13-INCH   MORTAR — SERVICE.  163 

tion,  commanding :  MuzziiE  right  ;  Muzzle  left;  Mortar 
right;  Mortar  left,  according  as  desired. 

For  muzzle  right :  Nos.  3  and  5  heave  to  the  rear,  and  Nos.  4 
and  6  to  the  front,  at  the  command  Heave  from  the  gunner, 
who  repeats  the  alternate  commands  heave  and  embar  as  often 
as  may  be  necessary. 

For  muzzle  left :  Same  as  above,  except  that  Nos.  3  and  5  heave 
to  the  front  and  Nos.  4  and  6  to  the  rear. 

Mortar  right  (or  left)  is  executed  by  giving  the  muzzle  the 
proper  direction  and  running  the  mortar  in  battery,  or  by  giv- 
ing the  muzzle  the  opposite  direction  and  running  the  mortar 
from  battery.  In  either  case  the  manoeuvre  is  completed  by 
throwing  the  muzzle  in  the  proper  direction  on  its  platform  by 
the  commands  already  given. 

The  direction  having  been  given,  the  gunner  commands : 
Halt,  and  the  eccentrics  are  thrown  out  of  gear  as  described  in 
par.  363.  To  prevent  the  carriage  from  moving  out  of  line  when 
the  eccentrics  are  thrown  out  of  gear,  the  wheels  should  be  firmly 
chocked  in  front.  This  is  done  by  Nos.  1  and  2  at  the  command 
halt. 

It  necessary  to  rectify  the  direction  of  the  piece  after  the  eccen- 
trics are  out  of  gear,  the  gunner  causes  Nos.  5  and  6,  assisted  by 
all  the  other  cannoneers,  to  embar  under  the  rear  notches  with 
the  maneuvering  handspikes  and  move  the  trail  to  the  right  or 
left.  No.  3  pricks  the  vent  and  then  prepares  the  lanyard  and 
primer ;  No.  4  embars  with  the  elevating-bar  through  the  ratchet- 
post,  and,  assisted  by  No.  5,  raises  or  depresses  the  breech  at  the 
command  of  the  gunner.  The  gunner  applies  the  quadrant  to 
the  face  of  the  piece,  giving  the  commands  to  No.  4,  Raise  or 
Lower,  until  the  piece  is  at  the  required  elevation,  usually 
forty-five  degrees,  makes  a  signal  to  No.  4,  who  then  unbars, 
places  the  elevating-bar  in  its  place  on  the  ground,  and  resumes 
his  post.  The  gunner  commands:  Ready,  returns  the  quad- 
rant to  the  basket,  receives  the  primer  from  No.  3,  and,  passing 
the  lanyard  under  the  pipe,  inserts  the  primer  in  the  vent,  and 
goes  where  he  can  best  observe  the  shot. 

The  cannoneers,  except  No.  3,  go  at  the  command  ready  to 
the  rear  of  the  platform  and  form  detachment  as  in  detachment 
reai\  leaving  No.  4  uncovered;  No.  3,  holding  the  handle  of  the 
lanyard  in  his  right  hand,  back  of  the  hand  up,  moves  three 
yards  obliquely  to  his  left  and  rear,  and  breaks  oft'  to  his  left  and 
rear  a  full  pace  with  his  left  foot,  his  left  hand  hanging  naturally 
bv  his  side. 

1.  Number  one  (or  the  like),  2.  Fire. 
366*  No.  3,  turning  his  face  from  the  piece,  pulls  the  Ian- 


164  13-INCH   MORTAR — SERVICE. 

yard  quickly,  but  steadily,  and  fires.  On  the  discharge  of  the 
piece,  all  except  the  gunner  return — without  command — to  their 
posts;  as  soon  as  the  shell  strikes,  the  gunner  returns  to  his 
post. 

When  exercising  for  instruction  only,  the  instructor  continues 
it  by  causing  the  piece  to  be  moved  toward  the  rear  of  the  plat- 
form by  the  command  From  battery.    He  then  commands  : 

1.  Unload. 

367.  The  gunner,  receiving  the  shell-hooks  from  No.  2, 
mounts  upon  the  step  of  the  carriage  and  attaches  them  to  the 
shell ;  No.  2  puts  the  carrying-bar  through  the  ring  of  the  hooks, 
am!,  assisted  by  Nos.  3,  5,  and  6,  raises  the  shell  from  the  bore 
of  the  piece  and  carries  it  to  its  former  place. 

In  doing  this  the  cannoneers  apply  themselves  as  in  bringing 
up  the  shell,  but  move  in  the  reverse  order.  All  then  resume 
their  posts. 

The  instructor  continues  the  series  of  commands,  beginning 
with  In  battery. 

In  changing  posts,  No.  2  passes  by  the  front  of  the  piece. 

To  load  without  the  numbers,  and,  to  fire. 

To  load  and  Jire  continuously,  and  to  cease  firing. 

Executed  as  in  pars.  246  and  247. 

To  secure  piece  and  replace  equipments. 

The  instructor  causes  the  piece  to  be  placed  on  the  centre  of 
the  platform,  and  commands : 

Replace  equipments. 

368.  Nos.  5  aud  6  replace  the  handspikes  on  the  truck-wheels  ; 
No.  2  puts  in  the  tompion  and  replaces  the  basket  between  the 
cheeks,  in  rear;  No.  4  assists  the  gunner  to  take  off  his  sleeves; 
No.  3,  in  like  manner,  assists  No.  1 ;  the  gunner  receives  the 
equipments  from  the  cannoneers  and  replaces  them  in  the  basket ; 
Nos.  3  and  4  replace  the  trestles  and  plummets. 

Remarks. 

If,  in  securing  the  mortar,  the  muzzle  has  been  so  far  depressed 
that  the  elevating-bar  cannot  be  engaged  in  the  ratchets,  a  trace 
chain  may  be  doubled  over  the  ratchet  and  the  bar  engaged  in 
the  bight  of  the  chain  ;  or  the  elevating-bar  maybe  placed  in  the 
ratchets  perpendicular  to  the  axis  of  the  piece,  and  a  wooden 
handspike  engaged  over  the  bar  and  under  the  nuts  or  T-plates 
of  the  cheeks,  aud  the  mortar  thus  elevated. 


10-INCH   SEA-COAST   MORTAR — SERVICE. 


165 


A  bar  known  as  Piper's  loading  bar  is  a  far  more  conven- 
ient implement  than  the  shell-hooks  for  carrying  and  loading 
the  shell.  It  is  simply  a  bar  of  round  iron  about  two  feet  long, 
fashioned  into  a  ring  at  one  end  for  a  handle,  and  having  a  screw 
cut  on  the  other  end,  which  screws  into  a  shallow  hole  tapped  in 
the  shell  at  a  short  distance  from  the  fuse-hole.  When  the  shell 
is  lowered  into  the  bore  and  adjusted,  the  bar  is  unscrewed  and 
removed. 

To  insure  the  ignition  of  the  fuse  of  mortar  shells,  the  end  of 
the  fuse-plug  and  the  shell  around  it  should  be  smeared  with 
treacle,  varnish,  mucilage,  or  any  other  sticky  substance,  and 
after  the  shell  is  in  the  bore  a  little  fine-grain  powder  thrown 
on  it. 

In  rainy  weather,  great  care  must  be  observed  to  keep  the 
charge  dry  during  the  operation  of  loading.  This  may  be  ef- 
fected by  covering  the  piece  with  a  paulin,  the  front  part  of 
which  can  be  raised  while  the  loading  is  going  on. 


Service  of  a  10-inch  Sea -coast  Mortar  (eccentric 

axle). 

Description  of  Piece. 
369.  Mortar,  cast-iron  ;  smooth-bore,  without  chamber. 


Designation. 


Calibre......* 

Weight * 

Preponderance 

Length  of  piece 

Length  of  bore 

Windage 

Charge  (maximum),  mortar  powder 

Charge  to  fill  shell 

Charge  to  burst  shell 

Charge  to  blowout  fuse 

Weight  of  carriage 


Lbs. 


7300 
00 


12 
5 
2 

0.5 
2924 


Inch. 


10 


47.05 
32.5 
0.13 


The  carriage  is  of  wrought-iron,  and  is  provided  with  an  eccen- 
ricaxle  and  truck-wheels  similar  to  the  carriage  for  the  13-inch 
lortar.  {Par.  360.)  The  mortar  is  fired  from  a  wooden  plat- 
arm.    (Par.  228.) 

With  heavy  charges,  the  shell  used  in  the  10-inch  gun  may  be 

sed  for  this  mortar.    The  10-inch  siege-mortar  shell  may  be 

sed  with  moderate  charges. 


166 


10-INCH   SEA-COAST   MORTAR — SERVICE. 


Ranges, 

With  10-inch  siege-mortar  shells,  filled  with  sand  (weight  96.5 
pounds). 


Charge. 

Elevation. 

Range. 

Tune  of 
Flight. 

Lbs.  oz. 

Degrees. 

Yards. 

Seconds. 

5       0 

45 

2720 

25.20 

5      8 

45 

2983 

26.33 

6      0 

45 

3005 

26.50 

6      8 

45 

3254 

26.75 

7      0 

45 

3325 

27.50 

With  10-ineh  gun  shells,  filled  with  sand  (weight  104  pounds)* 


Charge. 

Elevation. 

Range. 

Time  of 

Flight. 

Lbs. 

oz. 

Degrees. 

Yards. 

Seconds. 

7 

8 

45 

3471 

28.10 

8 

0 

45 

3G38 

29.G0 

8 

8 

45 

3648 

29.75 

9 

0 

45 

3677 

30.75 

9 

8 

45 

4096 

30.40 

10 

0 

45 

4301 

31.25 

10 

8 

45 

4345 

32.00 

11 

0 

45 

4458 

33.50 

11 

8 

45 

4465 

34.00 

12 

0 

45 

4536 

not  taken. 

To  serve  the  piece. 

Six  men  are  necessary :  one  chief-of-detachment,  one  gunner, 
and  four  cannoneers. 

The  implements  and  equipments  are  the  same  as  for  the  13- 
inch  mortar  (par.  301),  omitting  the  sponge  and  adding  a  wiper, 
a  wiper-stake,  and  a  maul,  and  are  distributed  as  in  the  service 
of  the  10-inch  siege  mortar  (par.  344),  except  that  when  there 
are  no  hooks  on  the  cheeks  for  the  truck  handspikes,  these  arc 
laid  on  the  platform  in  front  of  Xos.  1  and  2,  parallel  to  the 
cheeks,  small  ends  to  the  front,  and  are  returned  to  this  posi- 
tion whenever  not  actually  in  use. 


13-INCH   MORTAR — CENTRE   PINTLE— -SERVICE.     167 

The  mortar  is  raanoeuvered  on  its  platform  as  preM'iibed  for 
the  13-inch  mortar,  and  by  the  same  commands.     (Par.  303.) 

The  loading  and  firing  are  executed  as  prescribed  for  the  serv- 
ice of  the  10-inch  siege  mortar.    (Par.  340  et  seq.) 

Service  of  a  13-inch  Mortar  (centre-pintle  carriage). 

(Fig.  3,  Plate  9.) 

Description  of  Piece. 

3*70.  This  piece  differs  from  the  one  described  in  par.  300 
only  in  the  method  of  mounting.  Both  have  the  same  carriage, 
but  instead  of  the  carriage  resting  directly  on  the  platform,  as 
in  the  first,  the  carriage  for  the  centre  pintle  is  mounted  on  a 
chassis  itself  resting  on  the  platform. 

The  chassis  is  attached  at  its  centre  to  the  platform  by  a  pin- 
tle, and  traverses  upon  iron  circles  in  the  manner  usual  for  this 
class  of  carriages. 

In  addition  to  the  eccentric  axle  at  the  middle  of  the  chassis, 
for  throwing  it  in  and  out  of  gear,  them  is  another  axle,  also 
eccentric,  carrying  a  traverse-wheel  which  works  between  the 
parts  of  a  double  transom  on  the  front  end  of  the  chassis.  This 
wheel  communicates  motion  to  the  chassis. 

A  crane  is  attached  to  the  left  cheek  for  hoisting  the  shell  to 
the  muzzle. 

The  chassis  has  an  inclination  to  the  rear  of  three  degrees;  it 
is  of  wrought-iron,  and  weighs  5500  pounds. 

The  ranges  are  as  given  in  par.  300. 

To  serve  the  piece. 

8*71.  Eight  men  are  necessary:    one  chief-of-detachment, 
one  gunner,  and  six  cannoneers. 
The  implements  and  equipments  are  arranged  as  follows  : 

Truck  handspikes  (iron)...}  T^te^°h  S',de'  °n  the  h°°ks  °f 

Wheel-chocks  (iron) One  on  each  side,  on  the  burtons. 

Blocks  and  fall Attached  to  the  crane. 

The  other  implements  (omitting  the  wooden  handspikes)  are 
the  same,  and  are  arranged  in  the  same  manner  as  in  par.  300. 

To  prepare  for  pointing  the  mortar. 

3?2*  In  every  position  of  the  piece,  the  plane  of  fire  passes 
trough  and  includes  the  axis  of  the  pintle.  The  position  of 
his  axis  is  determined  by  suspending  over  the  centre  of  I  he  pin- 


168     13-INCH    MORTAR — CENTRE    PINTLE — SERVICE. 

tie  a  plummet ;  this  is  most  readily  done  by  using  a  light  trestle, 
about  six  feet  high,  with  legs  far  enough  apart  to  reach  across 
the  chassis,  allowing  it  to  be  traversed  about  a  foot  hi  either 
direction. 

The  highest  point  of  metal  at  the  muzzle  is  determined  in  the 
usual  manner.  This  being  marked,  serves  the  same  purpose 
that  a  front  sight  does  on  a  gun — the  rear  sight  being  the  plum- 
met over  the  pintle,  or  one  placed  in  rear  of  the  platform  in  the 
plane  including  the  highest  point  of  metal  and  the  object. 

If  the  object  can  be  seen  from  the  mortar,  establish  a  plummet 
in  rear  of  the  platform,  in  line  with  the  one  over  the  pintle  and 
the  object.  The  trestle  over  the  pintle  is  then  removed.  The 
aiming  is  accomplished  by  sighting  on  the  object  from  the  plum- 
met in  rear,  and  traversing  the  chassis  until  the  highest  point  of 
metal  falls  on  this  line. 

If,  as  is  generally  the  case,  the  object  is  cut  off  from  view  by 
an  epaulment,  a  point  must  be  interpolated  on  the  line  from  the 
object  to  the  plummet  over  the  pintle.  This  is  accomplished  as 
explained  in  par.  343.  On  the  line  thus  determined,  a  plummet 
is  suspended  in  rear  of  the  platform,  as  before,  and  the  trestle 
over  the  pintle  removed. 

The  Lorain  sight  may  be  used  on  this  mortar. 

When  Dyer's  apparatus  is  used,  the  direction  is  given  as  ex- 
plained in  par.  210. 

Remark. 

Owing  to  the  fact  that  the  top-carriage  has  some  lateral  play 
on  the  chassis,  it  is  well  to  have  the  line  of  metal  marked  in  the 
usual  waj%  and  then,  in  aiming,  bring  this  line  in  the  plane  of 
sight. 

To  distribute  the  implements  and  equipments. 

373.  The  instructor  commands : 

1.  Take  equipments. 
Executed  as  in  par.  362. 

To  serve  the  piece. 

374.  The  piece  will,  habitually,  be  in  battery  while  being 
loaded.  It  is  in  battery  when  the  soles  of  the  cheeks  are  against 
the  h inters. 

375.  The  instructor  commands  : 

1.  In-battery. 

Executed  as  in  par.  363,  adding,  Nos.  1  and  2  will  unchock 
the  wheels  of  the  top-carriage. 


13-INCH    MORTAR — CENTRE   PINTLE — SERVICE.     Kit) 

1.  From  battery. 

376.  Executed  as  in  par.  363,  except  that  Nos.  1  and  2  fol- 
low up  the  movement  and  keep  the  wheel-chocks  closely  ap- 
plied to  the  wheels. 

1.  By  the  numbers,  2.  LOAD. 

377.  Executed  as  laid  down  in  par.  364,  with  the  following 
exceptions :  When  the  shell  is  brought  up  it  is  placed  under  the 
crane,  the  carping-bar  withdrawn,  and  the  pulley  attached  to 
the  sholl-hooks  by  No.  4 ;  Nos.  5  and  6  rmi  up  the  shell,  No.  4 
steadying  it.  When  sufficiently  raised,  it  is  swung  over  the 
muzzle,  and  lowered  to  its  place  in  the  bore  as  explained  in  par. 
264;  No.  4  swings  back  the  crane  and  keys  it  to  the  cheek.  All 
resume  their  posts. 

1.  Aim. 

378.  The  gunner  places  himself  in  rear  of  the  chassis,  and 
commands : 

1.  Chassis  in-gear,  2.  Heave. 

At  the  first  command,  No.  1  unlocks  the  eccentric  of  the  front 
wheel ;  No.  2  embars  with  his  handspike  in  the  eccentric  .socket 
of  this  wheel,  and  is  assisted  by  No.  I ;  Nos.  o  and  6  embar  in 
the  eccentric  sockets  of  the  truck-wheels  upon  the  sides  of  the 
chassis.  At  the  second  command,  the  chassis  is  thrown  in  gear; 
No.  1  locks  the  eccentric  of  the  front  wheel,  and  No.  2  inserts 
his  handspike  in  the  uppermost  mortise  of  this  wheel,  No.  I 
still  assisting  him. 

The  gunner  then,  sighting  by  the  plummet,  commands :  Muz- 
zle right,  or  Muzzle  lept.  Nos.  1  and  2,  applying  them- 
selves to  the  handspike  in  the  front  wheel,  give  the  piece  the 
right  direction.  If  the  chassis  traverses  with  difficulty,  Nos.  1 
and  2  embar  separately,  each  with  a  handspike  in  a  mortise  on 
his  own  side. 

The  direction  being  given,  the  gunner  commands  :  1.  Chassis 
out-of-gear,  2.  Heave. 

Executed  in  a  manner  similar  to  that  of  throwing  it  into  gear. 

All  the  cannoneers  then  resume  their  posts. 

No.  3  pricks  the  vent,  and  then  prepares  the  primer  and  lan- 
yard. The  elevation  is  given  as  explained  in  par.  365.  The 
gunner  commands :  Ready,  receives  the  primer  from  No.  3, 
inserts  it  in  the  vent,  and  goes  where  he  can  best  observe  the 
effect  of  the  shot. 

The  cannoneers  go  to  the  rear  as  explained  in  par.  365. 


170  GATLING  GUN. 

1.  Number  one  (or  the  like),  2.  Fire. 

Executed  as  in  par.  366. 

The  remaining  exercises  are  executed  as  explained  in  pars* 
367  and  368. 

When  Dyer's  pointing  apparatus  is  used,  the  gunner,  after  the 
chassis  is  thrown  in  gear,  goes  to  the  instrument  on  the  parapet, 
sights  through  it  upon  the  object,  notes  the  degree,  returns  and 
causes  the  piece  to  be  traversed  until  the  pointer  on  the  chassis 
is  at  the  same  degree  on  the  arc  of  the  platform. 

GrATLING    GUN. 

(Fig.  1,  Plate  17.) 

319.  The  Gatling  is  a  machine  gun  of  small  calibre,  throw- 
ing lead  projectiles.  It  is  used  for  field  service,  and  also  as  an 
auxiliary  in  the  armament  of  fortifications.  For  both  purposes, 
it  is  mounted  on  a  traveling  carriage. 

Two  calibres  have  been  adopted,  viz.:  the  1-inch,  which,  in 
addition  to  solid  projectiles,  throws  also  canister ;  and  the  0.45- 
inch,  which  uses  the  same  cartridge  as  the  regulation  rifle-mus- 
ket. 

The  general  features  of  the  mechanism  are  the  same  for  both, 
consisting  of  a  number  of  breech-loading  rifled  barrels,  grouped 
around  and  revolving  about  a  common  axis,  with  which  they 
are  parallel.  The  bore  of  each  barrel  extends  entirely  through 
it,  and  the  breech  is  chambered  to  receive  a  flange,  centre-fire, 
metallic-case  cartridge.  The  barrels  are  rigidly  attached  to  a 
central  shaft  extending  to  their  rear,  and  supporting  a  cylindri- 
cal breech -casing,  which  carries  within  it  all  the  machinery  by 
which  the  barrels  are  loaded  and  tired.  A  crank  upon  the  right 
side  of  this  casing  is  used  for  operating  the  machinery.  The 
barrels  are  discharged  successively  as  they  revolve  with  the 
shaft. 

Each  revolution  of  the  crank  gives  one  discharge  with  the 
1-inch  gun;  with  the  0.45-inch,  three  discharges  are  made  by 
each  revolution.  The  former  is  capable  of  firing  150  shots  per 
minute ;  the  latter,  500  shots. 


1-INCH    GATLIXG — SERVICE. 


171 


Service  of  the  1-inch  Gatling. 
Description  of  Piece. 


Extreme  length  of  piece ~ 

Length  of  barrel ~ 

Length  of  breech-casing ~ 

Length  of  feed-case 

Cartridges  in  each  case 

Cartridges  in  each  ammunition  chest 

Total  number  of  rounds  for  each  guu 

Gun  (weight) 

Total  weight  of  gun,  implements,  carriage  and 

limber., 

Number  of  barrels 

Number  of  grooves 

Depth  of  grooves 

Twist:  one  turn  in  six  feet 

Preponderance 

Number  of  horses  for  each  piece 

Number  of  horses  for  each  caisson.................... 


12 

472 
2592 


6 
C 


0 
6 


68.15 

as. 

21.5 
14.5 


(U)l 


The  piece  is  mounted  on  the  3-inch  field-gun  carriage. 
For  field  service,  each  piece  is  accompanied  by  one  caisson. 

To  serve  the  piece. 

380.  Ten  men  are  necessary :  one  chief-of-detachment,  one 
gunner,  and  eight  cannoneers. 

The  equipments  consist  of  three  cartridge-pouches,  which  are 
hung  on  the  knob  of  the  cascable. 

At  the  command  of  the  instructor:  Take  equipments,  the 
gunner  steps  to  the  piece  and  distributes  them  to  Nos.  4,  5,  and 
7,  who  carry  them  slung  from  the  left  shoulder  to  the  right  side. 
Kos.  1  and  2,  passing  around  in  front  of  the  axle,  assist  the  gun- 
ner in  removing  the  cover,  which  is  folded  and  placed  on  the 
limber  chest.  It  should  never  be  laid  on  the  ground,  as  it  would 
be  liable  to  pick  up  sand  and  dirt,  injurious  to  the  working  of 
the  parts. 

When  the  piece  is  unlimbered,  the  end  of  the  pole,  or  if  with 
horses  the  heads  of  the  lead  horses,  are  six  5Tards  from  the  small 
and  of  the  trail  handspike,  the  pole  pointing  in  the  direction  of 
the  piece. 

Post  of  cannoneers ,  piece  unlimbered. 

(Fig.  2,  Plate  17.) 

881.  The  gunner  is  ou  the  left  of  the  trail  handspike,  nearly 


172  1-INCH   GATLING — SERVICE. 

touching  it,  heels  on  a  line  with  the  end  ;  Nos.  1  and  2  are  eight- 
een inches  outside  of  the  wheels.  No.  1  on  the  right  and  No. 
2  on  the  left,  in  line  with  the  rear  part  of  the  wheels;  Nos.  3 
and  4  are  opposite  the  trail  handles,  in  line  with  Nos.  1  and  2, 
No.  3  on  the  right.  No.  4  on  the  left;  No.  5  is  five  3rards  to  the 
right  of  No.  4,  in  line  with  Nos.  2  and  4;  No.  6  directly  behind 
the  limber  chest,  and  No.  7  two  feet  behind  the  left  limber- 
wheel.  All  face  toward  the  piece.  No.  8  attends  to  the  supply 
■of  ammunition,  and  is  with  the  caisson  or  at  the  magazine. 

382.  The  commands  of  the  instructor  are:  1st.  Load;  2d. 
Commence  firing;  3d.  Cease  firing;  4th.  Secure  piece. 
These  are  repeated  by  the  gunner. 

The  duties  of  the  gunner  are  to  direct  the  piece  ;  observe  that 
the  shots  are  striking  at  the  proper  point ;  see  that  the  supply  of 
.ammunition  is  ki^pt  up;  throw  the  oscillating  apparatus^  in  and 
•out  of  gear ;  remove  disabled  locks ;  see  that  No.  1  is  relieved  by 
No.  3  when  fatigued  by  rapid  firing ;  and  have  general  super- 
vision of  the  gun. 

The  duties  of  No.  1  are  to  turn  the  crank;  see  that  the  car- 
tridges are  feeding  properly  from  the  case ;  and  use  the  ejecting 
rod  when  necessary. 

The  duties  of  No.  2  are  to  supply  the  piece  with  ammunition 
by  inserting  the  feed-cases  into  the  hopper,  and  to  see  that  the 
cartridges  are  feeding  properly. 

The  duties  of  No.  3  are  to  assist  the  gunner  in  giving  the  di- 
rection. 

The  duties  of  No.  6  are  to  give  out  ammunition  from  the  lim- 
ber chest  to  Nos.  5  and  7,  who  alternate  in  bringing  it  up  to 
No.  2. 

To  serve  the  piece. 

383*  The  instructor  commands:  Load. 

The  gunner,  repeating  the  command,  takes  hold  of  the  trail 
handspike  at  the  end  with  the  right  hand  and  at  the  centre  with 
his  left ;  looks  over  the  top  of  the  piece  and  gives  the  general 
direction.  lie  then  steps  to  the  breech  and  adjusts  the  rear 
sight  to  the  required  distance;  sights  through  the  notch  of  the 
rear  sight;  seizes  the  handles  of  the  elevating  screw  and  gives 
the  proper  elevation,  and,  assisted  by  No.  3  at  the  trail  hand- 
spike, gives  the  exact  direction.  The  piece  being  pointed,  he 
stations  himself  where  he  can  best  observe  the  effect  of  the  shots. 

When  the  shots  are  not  striking  properly,  the  gunner  places 
himself  at  the  elevating  screw  as  before,  and,  with  the  assistance 
of  No.  3  at  the  trail  handspike,  readjusts  the  pointing. 

No.  1  places  himself  rapidly  between  the  piece  and  the  wheel, 


1-INCH   GATLXNG — SERVICE.  173 

in  rear  of  the  axle,  facing  to  the  front ;  breaks  to  the  rear  with 
the  left  foot;  free.-*  the  crank  from  its  catch,  and  seizes  the 
crank  handle  with  his  right  hand,  taking  care  not  to  turn  it  until 
the  command  commence  firing  is  given.  Nos.  1  and  3  exchange 
duties  and  numbers  when  so  ordered  by  the  gunner. 

No.  2  stations  himself  at  the  hopper  in  a  position  similar  and 
opposite  to  that  of  No.  1,  but  facing  to  the  right;  receives  the 
full  feed-cases,  one  at  a  time,  from  No.  o,  and  introduces  them 
into  the  hopper,  the  hole  to  the  right  and  projectiles  to  the  front. 
He  calls  case  as  the  last  cartridge  passes  the  hole  ;  receives  a  full 
feed-case  with  his  right  hand  from  No.  5,  and  inserts  it  in  the 
hopper  as  the  eniptj'  case  is  removed  b)'  No.  4,  thus  keeping  a 
continuous  stream  of  cartridges  fed  to  the  gun.  Nos.  2  and  4 
exchange  duties  and  numbers  when  ordered  by  the  gunner,  but 
without  interrupting  the  tiring. 

.  No.  3  goes  to  the  end  of  the  trail  handspike ;  seizes  it  with 
both  hands  as  soon  as  the  gunner  goes  to  the  elevating  screw, 
and  prepares  to  move  it  to  the  right  or  left  at  a  signal  from  the 
gunner.  He  remains  at  the  end  of  the  trail  handspike,  and  as- 
sists the  gunner  to  point  the  piece. 

No.  4  places  himself  in  front  of  the  axle,  between  the  left 
wheel  and  piece,  facing  to  the  rear.  When  No.  2  calls  case,  lie 
removes  the.  empty  case  from  the  hopper,  puts  on  its  cover  which 
he  has  received  from  No.  5,  and  deposits  the  empty  case  in  his 
pouch  until  called  for  bj'  No.  5. 

No.  5  runs  to  the  ammunition  chest;  receives  in  his  pouch 
four  full  cases  from  No.  6 ;  takes  them  to  the  piece,  and  places 
himself  to  the  right  and  rear  of  No.  2,  facing  to  the  right.  He 
then  removes  the  cover  from  a  case  and  hands  it  to  No.  4;  the 
case  to  No.  2..  This  he  continues  until  his  pouch  is  empty,  when 
he  makes  a  signal  to  No.  7  to  take  his  place;  gets  the  empty 
feed-cases  from  No.  4;  returns  them  to  the  limber;  receives  full 
cases  from  No.  6,  and  resumes  his  post;  meanwhile,  No.  7  as- 
sumes the  place  find  duties  of  No.  5  beside  No.  2.  When  the 
piece  is  limbered  up,  he  returns  all  the  cases  to  No.  6,  who  re- 
places them  in  the  ammunition  chest. 

Nos.  G  and  8  attend  to  the  supply  of  ammunition.  The  empty 
feed-cases  are  filled  at  the  limber  or  caisson,  care  being  taken  to 
nlace  the  projectile  to  the  left.  To  fill  a  feed-case,  rest  it  on 
he  left  fore-arm,  inclining  downwards  towards  the  elbow,  the 
*kle  containing  the  hole  uppermost,  the  open  end  supported  in 
he  palm  of  the  left  hand,  the  other  end  in  the  bend  of  the 
lbow.  The  first  cartridge  is  introduced  (point  to  the  left)  and 
Tadually  pushed  to  the  bottom  of  the  case  by  those  succeeding 


174  1-INCH   GATLING — SERVICE. 

it.    When  not  otherwise  engaged,  the  numbers  from  5  to  8,  in- 
clusive, are  employed  filling  cases. 

As  soon  as  No.  5  is  supplied  with  full  cases,  No.  7  gets  four 
full  Oases  in  his  pouch  and,  upon  the  signal  from  No.  5,  as- 
sumes the  place  and  duties  of  the  latter  beside  No.  2.  As 
soon  as  he  has  passed  all  of  his  cases  to  No.  2,  he  signals  No.  5 
to  take  his  place,  gets  the  empty  cases  from  No.  4,  returns  them 
to  the  limber,  and  gets  full  cases  in  his  pouch  ready  again  to 
relieve  No.  5. 

1.  Commence  firing. 

384.  This  command  is  repeated  by  the  gunner.  No.  1  turns 
the  crank  with  a  moderate  uniform  motion,  avoiding  all  sudden 
movements  or  lateral  wrenching,  and  allowing  ample  time  for 
the  cartridges  to  drop  from  the  feed-case  into  the  carrier.  He 
watches  the  hopper  to  see  that  the  cartridges  are  feeding  prop- 
erly. 

Should  anv  of  the  shells  not  be  thrown  out  after  firing,  or  the 
piece  become  jammed  in  any  manner,  he  will  at  once  notify 
the  gunner,  who  will  see  that  the  proper  means  are  taken  to 
remove  the  obstruction. 

If  the  gun  jams,  remove  the  feed-case  at  once,  open  the  hop- 
per, and  reverse  the  crank  until  all  the  cartridges  are  taken  out. 
This  will  be  found  to  save  time,  unless  the  cause  of  the  jamming 
is  evident,  and  in  the  immediate  vicinity  of  the  hopper. 

When  it  is  necessary  to  use  the  ejecting  rod,  No.  1  steps  to 
the  front,  unke\-s  it,  and,  under  the  direction  of  the  gunner, 
removes  the  obstruction  by  forcing  it  backwards. 

1.  Cease  firing. 

385.  At  this  command  from  the  instructor,  repeated  by  the 
gunner,  No.  1  ceases  to  turn  the  crank;  No. 4  removes  the  case, 
and  No.  2  opens  the  hopper;  the  gunner  directs  No.  1  to  slowly 
reverse  the  crank,  while  No.  2  removes  the  cartridges,  passing 
them  to  No.  4,  who  restores  them  to  the  feed-case,  which  he 
gives  to  No.  5  to  return  to  the  chest ;  No.  1  secures  the  crank 
by  the  latch,  and  all  resume  their  posts. 

A  partially-filled  feed-case  should  not  be  put  back  into  the 
ammunition  chest  without  being  filled  up,  as  the  cartridges  may 
become  inverted  and  jam  the  gun. 

If,  for  any  purpose,  it  is  desired  to  temporarily  arrest  the  fir- 
ing, the  instructor,  or  the  gunner,  commands:  Halt.  No.  1 
stops  turning  the  crank,  and  all  remain  at  their  positions  until 
the  instructor,  or  the  gunner,  commands:  COMMENCE  firing, 
or  Cease  firing. 


1-INCH   GATLING — SERVICE. 


175 


1.  Secure  piece. 

386*  The  gunner  steps  to  the  rear  of  the  piece  as  at  the 
command  load,  runs  down  the  elevating  screw,  turns  down 
the  front  and  lowers  the  rear  sight,  and,  with  the  assistance  of 
Nos.  1  and  2,  who  step  to  the  front  for  that  purpose,  places  and 
fastens  the  canvas  cover  upon  the  piece ;  all  then  resume  their 
posts. 

Service  of  piece  with  reduced  numbers. 

387*  When  the  number  of  cannoneers  is  reduced,  the  respect- 
ive duties  are  performed  as  indicated  by  the  following  table : 


Numbers  Re- 
tained. 

Distribution  of  Duties. 

I 

Gunner. 

I 

2 

24 

2  4 

7 

7 

2 

3           4 

5 

6    1 

G-.    1 

G.   1 

G.   1 

G. 

G. 

G. 

G. 

234567 

3  5  6  7 

1 

t 

1 

1 

3  '>  G  7  , 
3  5  6       4  2 
3       ,42 
3       i      4 

i 

5  6 
5 

67 

_ — — 

G-     1.2 

G-.    1,2.3 

G-.    1,2,3,4 

G-.    1,2,3,4,5 

G-.    1,2,3,4,5,6.. 

Nomenclature  of  the  1-inch  Gun. 

In  view. 

Main  shaft,  around  which  the  Ejector. 

barrels  are  clustered.  Cartridge  carrier. 

Front  plate,  which  supports  Crank. 

the  front  of  the  barrels.  Elevating  screw. 

Rear  plate,  which  supports  the  Elevating-screw  box. 


rear  end  of  tiie  barrels. 
Barrels. 
Gun  frame. 
Trunnions. 
Gun  face. 
Front  sight. 
Rear  sight. 
Breech-casing. 
Breech-casing  screws. 
Cascable  plate. 
Hopper. 


Elevating-screw  bed. 

Elevating-screw  handle* 

Wiping  rod  (brass). 

Ejecting  rod  (iron). 

Lock. 

Lock  tube. 

Lock  hammer. 

Lock  spring. 

Firing-pin. 

Extractor. 


Lock  cylinder. 
Rear-guide  nut. 
Cocking  ring. 
Cocking-ring  clamps. 
Spiral  cam. 


Within  the  breech- casing. 

Diaphragm. 

Diaphragm  plug. 

Gear-wheel. 

Pinion. 

Rear- cam  screw. 


176  1-INCH    GATLING — SERVICE. 

To  take  the  gun  apart, 

388.  The  piece  is  first  dismounted  and  placed  with  its  casing 
resting;  on  blocks.  Mounting  and  dismounting  are  best  accom- 
plished by  means  of  a  gin.  In  case  of  necessity,  it  may  be 
mounted  and  dismounted  as  a  field-piece,  care  being  taken  to 
place  blocks  of  wood  to  receive  the  gun  frame  and  to  prevent 
injury  to  the  front  sight,  or  to  the  barrels. 

The  operations  of  taking  apart  are  executed  in  the  following 
order : 

1st.  Block  up  the  frame  and  barrels. 

2d.  Remove  the  hopper. 

3d.  Remove  the  cascable  plate. 

4th.  Take  out  the  steady-pin  ;  then  turn  the  crank  downwards 
and  remove  the  crank  shaft  in  that  position. 

5th.  Remove  the  rear  sight,  and  take  out  the  large  gear-wheel. 

6th.  Take  out  the  rear  plug  in  the  diaphragm,  and  then  gen- 
tly revolve  the  gun  until  a  lock  presents  itself  on  a  line  with  the 
hole  in  the  diaphragm,  through  which  one  lock  after  another  is 
taken  out. 

7th.  Take  out  the  breech-casing  screws,  and  remove  the  cas- 
ing by  drawing  it  off  to  the  rear.  Care  is  taken  in  this  operation 
to  have  the  lock  cylinder  and  gun  supported,  so  as  to  keep 
the  axis  of  the  main  shaft  parallel  to  the  top  of  the  frame.  This 
is  necessary  to  prevent  the  rear  end  of  the  gun  from  dropping 
when  the  casing  is  removed. 

8th.  Remove  the  pin  from  the  large  nut  on  the  main  shaft  in 
rear  of  the  locks,  and  take  this  nut  off  by  turning  it  to  the  right; 
then  remove  the  lock  cylinder  and  carrier  from  the  main  shaft. 

The  spiral  cam  need  not  be  taken  out  of  the  casing  in  order 
to  take  the  gun  apart. 

To  assemble  the  gun. 

389.  1st.  Put  the  main  shaft  in  its  place  through  the  plates 
whicl i  hold  the  barrels,  and  then  put  in  their  proper  places  the 
carrier,  lock  cylinder,  and  large  rear  nut.  The  Litter  should  be 
screwed  up  tight  and  have  the  taper-pin  put  through  the  nut 
and  shaft. 

2i\.  Place  the  gun  within  the  frame,  and  let  the  front  end  of 
the  main  shaft  rest  in  the  hole  designed  for  it  in  the  front  of 
the  frame.  When  the  gun  is  in  this  position,  the  cocking  ring 
should  be  shoved  over  the  lock  cylinder  and  left  for  the  time 
loosely  around  the  carrier. 

3d.  Let  the  breech  of  the  gun  be  slightly  raised,  when  the 
breech-casing  can  be  shoyed  over  the  lock  cylinder  to  its  place ; 


0.45-INCH   UATMNG — 8ERVI0E. 


177 


then  screw  the  casing  to  the  frame,  putting,  hi  the  tiK-antiuic, 
the  cocking  ring  in  its  proper  place*.  Revolve  the  gun  to  the 
right  or  left  so  that  the  places  for  the  locks  will  come  on  a  line 
with  the  hole  in  the  diaphragm,  through  which  one  lock  at  a 
time  can  be  inserted  in  its  proper  position ;  afterwards  the  screw 
plug:  should  he  inserted  to  close  the  hole. 

4th.  Put  on  the  cog-wheels,  replace  the  crank  shaft,  pinion, 
and  steady-pin.  Put  on  the  rear  sight,  and  screw  on  the  cas- 
cnble  plate  and  hopper,  and  the  gun  is  ready  to  be  mounted. 
The  piece  is  mounted  on  a  3-inch  gun  carriage  widened  between 
the  cheeks  to  receive  it.  The  ammunition  chests  are  arranged 
for  twelve  travs. 


Service  of  the  0.45-inch  Gatlino  Gun,  mounted  on 

a  cavalry  cart. 

(Fig.  3,  Plate  17.) 
390.  Description  of  Piece. 


Extreme  length  of  piece ~ 

Length  of  barrel ~- 

Length  of  breech-casing 

Length  of  feed-case ~ •.« ~..... ...... 

Cartridges  in  each  case 

Cartridges  in  each  chest 

Onn  (weight) 

Total  weight  of  gnn,  carriage,  and  implements. 

Number  of  barrels _.......... 

Number  of  horses  to  draw  (good  roads) 

**       "       "     "      (bad  roads) 


No. 

Lbs. 

•*•••• 

••••• 

••* ••• 

40 

960 

•••••• 

144 

925 

10 

•••••• 

1 

2 

•••••• 

85.5 
18 
8.5 
20.25 


To  serve  the  piece. 

391.  Five  men  are  necessary  :  one  chief-of-detachment,  one 
gunner,  and  three  cannoneers. 

With  a  greater  number  of  cannoneers  a  more  rapid  and  con- 
tinuous fire  can  be  sustained,  (the  additional  men  refilling  feed- 
cases  and  bringing  up  ammunition,)  but  it  is  not  advisable  to 
expose  more  men  than  are  absolutely  necessary. 

The  animal  being  unhitched,  the  muzzle  is  pointed  in  the 
desired  direction,  by  the  gunner  and  Nos.  1  and  2,  working — 
the  former  at  the  shafts  and  the  latter  two  at  the  wheels;  the 
shafts  and  prop  are  then  allowed  to  rest  upon  the  ground. 
12 


178  0.45-INCH   GATLING — SERVICE. 

Posts  of  cannoneers,  piece  unhitched, 

392.  The  gunner  is  in  rear  of  the  piece,  covering  it,  and  at 
the  end  of  the  shaft;  No.  1  is  eighteen  inches  outside  and 
opposite  the  rear  part  of  the  right  wheel ;  No.  2,  two  feet  out- 
side and  opposite  the  rear  part  of  the  left  wheel ;  No.  3,  five 
yards  in  rear  of  and  covering  No.  1,  all  facing  the  piece. 

The  cover  is  removed  from  the  piece  by  the  gunner,  assisted 
in  front  by  No.  1,  who  folds  and  places  it  in  the  tool  box,  and 
resumes  his  post. 

The  commands  of  the  instructor  are  :  1.  Load;  2.   Commence 
firing;  3.  Cease  firing;  4.  Secure  piece;  and  are  repeated  by 
the  gunner. 

The  duties  of  the  gunner  and  No.  1  are  as  prescribed  for  the 
1-inch  gun. 

The  duties  of  No.  2  are  to  supply  the  piece  with  ammunition, 
by  taking  the  feed-cases  from  the  ammuntion  chest  and  insert- 
ing them  into  the  hopper,  and  to  see  that  the  cartridges  are 
feeding  properly. 

Service. 

393.  The  instructor  commands  :  Load.  The  gunner,  repeat- 
ing the  command,  steps  to  the  rear  of  the  piece,  throws  his  right 
leg  over  the  shaft,  reaches  forward,  turns  up  the  front  sight,  and 
adjusts  the  rear  sight  for  the  required  distance.  He  then  gives 
the  piece  the  proper  elevation  by  means  of  the  elevating  screw, 
correcting  the  direction  with  the  traversing  screw ;  should  any 
considerable  change  be  required,  he  loosens  both  clamp  screws 
and  shifts  the  bed-plate,  being  very  careful  to  refasten  the  clamp 
screws.    He  then  resumes  his  post. 

No.  1,  as  the  gunner  resumes  his  post,  springs  in  by  a  side 
step  to  his  left,  close  to  the  shaft,  frees  the  crank  from  its  latch, 
and  seizes  the  handle  with  his  right  hand,  being  careful  not  to 
turn  it  until  the  command  commence  firing  is  given. 

No.  2,  stepping  to  his  right  and  over  I  lie  one  nearest  to  him, 
takes  his  place  between  the  shafts  in  rear  of  the  left  ammunition 
chest,  opens  it,  takes  a  feed-case  with  his  left  hand,  withdraws 
it  from  the  chest  and  seizes  it  at  the  middle  with  the  right  hand, 
back  of  the  hand  up,  turns  it  until  the  spring  shall  be  down,  the 
slot  to  the  right,  and  inserts  it  into  the  hopper;  he  then  takes 
another  feed-case,  seizing  it  as  before,  and  stands  ready  to  re- 
move the  empty  case  with  his  left  hand,  and  insert  the  full  one 
into  the  hopper  with  his  right. 

1.  Commence  firing. 

394*  The  gunner  steps  to  the  side  from  which  he  can  best 
observe  the  effect  of  the  shot. 


0.45-INCH   GATLING — SERVICE.  179 

No.  1  turns  the  crank  with  a  moderate  uniform  motion,  tak- 
ing care  not  to  derange  the  position  of  the  gun  by  sudden  Jerks 
or  lateral  wrenching ;  should  any  of  the  shells  not  be  thrown 
out  after  firing,  or  the  piece  become  Jammed  in  any  manner,  he 
will  at  once  notify  the  gunner,  who  will  see  that  the  proper 
means  are  taken  to  remove  the  obstruction. 

No.  2,  as  soon  as  the  feed-case  is  empty,  seizes  it,  and,  after 
replacing  it  by  a  full  one,  returns  the  empty  case  to  the  chest, 
taking  care  that  the  spring  enters  first  and  is  on  the  under  side, 
and  then  proceeds  as  before. 

The  ammunition  in  the  left  chest  being  nearly  exhausted.  No. 
2  notifies  the  gunner,  who  calls  up  No.  3,  who  takes  his  post  in 
rear  of  and  opens  the  right  chest,  and  stands  ready  to  pass  the 
full  cases  to  No.  2,  in  rear  of  No.  1.  In  taking  the  feed-case 
from  the  chest,  No.  3  seizes  it  first  at  the  end,  afterwards  just 
above  the  middle  with  the  left  hand,  and  hands  it  to  No.  2,  so 
that  when  the  latter  seizes  it,  which  he  does  with  his  right  hand 
at  the  middle,  the  spring  shall  be  down  and  the  slot  to  his 
right ;  No.  2  passes  the  empty  case  with  his  left  hand  to  No.  3, 
who  receives  it  with  his  right  and  places  it  in  the  chest. 

1.  Cease  firing. 

395*  No.  1  ceases  to  turn  the  crank ;  No.  2  removes  the  case 
from  the  hopper;  the  gunner  steps  to  the  rear  of  the  piece,  opens 
the  hopper,  and  directs  No.  1  to  slowly  reverse  the  crank,  when 
he  removes  the  cartridges  which  have  not  been  fired,  passing 
them  to  No.  2,  who  restores  them  to  the  feed-case  and  replaces 
it  in  the  chest,  or  hands  it  to  No.  3  if  the  right  chest  is  being 
used;  No.  1  secures  the  crank  by  the  latch,  and  all  resume  their 
posts. 

1.  Secure  piece. 

396.  The  gunner  steps  to  the  rear  of  the  piece  as  at  the  com- 
mand load)  runs  down  the  elevating  screw,  turns  down  the  front 
and  lowers  the  rear  sight,  and,  with  the  assistance  of  No.  1,  who 
steps  to  the  front  for  that  purpose,  places  and  fastens  the  canvas 
cover  upon  the  piece ;  both  then  resume  their  posts. 

Precautions  to  be  observed, 

397.  (a)  Never  lay  the  cover  upon  the  ground,  as  it  is  liable 
to  pick  up  sand  and  dirt,  which  may  derange  the  working  of  the 
parts. 

(6)  A  partially-filled  feed-case  should  not  be  put  back  into  the 
ammunition  chest  without  being  filled  op,  as  the  cartridges  may 
become  inverted  and  jam  the  gun. 


180  0.45-INCH    GATLING — SERVICE. 

(c)  If  the  gun  jams,  remove  the  feed-case  at  once,  open  the 
hopper,  and  reverse  the  crank  until  all  the  cartridges  are  taken 
out.  This  will  he  found  to  save  time,  unless  the  cause  of  the  jam- 
ming is  evident  and  in  the  immediate  vicinity  of  the  hopper. 

(d)  See  that  all  the  parts  are  kept  well  oiled  to  prevent  fric- 
tion and  scouring. 

NOMENCLATUBE  OP  THE  0.45-INCH  GUN. 

39  8 .  Components. 

Adjustable-screw  nut.  Rear-sight  screws. 

Barrels  (10).  Front  plate  for  barrels. 

Breech-casing.  Front  sight. 

Breech-casing  screws  (6).  Front-sight  screws. 

Bushings  (10).  Gas  collar. 

Cartridge  carrier.  Gun  frame. 

Cartridge-shell  ejector.  Hopper. 
Cartridge-shell  ejector  screws    Hopper  hinge. 

(3).  Hopper-hinge  pin. 
Cartridge  -  shell     extractor        Hopper-hinge  screws  (2). 

block.  Hopper  latch. 
Cartridge -shell     extractor-      Hopper-latch  screws. 

block  screws  (2).  Lock  cylinder. 

Cascable  plate.  Lock-cylinder  screws  (2). 

Cocking  device.  Lock  extractor. 

Crank.  Lock-extractor  screws. 

Crank  latch.  Lock-extractor  sleeve. 

Crank  shaft.  Lock-extractor  sleeve  screws 
Diaphragm.  (2). 

Dowel-pins.  Lock  main-springs  (10). 

Extractor-hooks  (10).  Lock  nuts  (10). 

Firing-pins  (10).  Lock  tubes  (10). 

Front  cap.  Spiral  cam. 

Main  shaft.  Spiral-cam  screws  (2). 
Oscillating   thread    nut    and    Trunnions  (2). 

washer.  Washer  for  front  end  of  main 
Rear-guide  nut.  shaft. 

Rear  plate  for  barrels.  '    Worm. 

Rear  sight.  Worm  gear. 

Appendages. 

Adjusting  screw-wrench.  Pin-wrench. 

Brass  wiping-rod.  Rear-guide  nut  wrench. 

Clamp  for  worm  gear.  Shell  driver. 

Feed-cases,  straight  (48).  Small  screw-driver. 

Lock  screw-driver.  T  screw-driver. 


0.45-IKC11    UATUXU--  .-EKV1CE.  lbl 

The  carriage. 

Shafts.  Ammunition  chests  (3). 

Eye-bolts  and  straps  (6).  Chest  handles  (2). 

Split  iter- bar.  Lid. 

Step.  Lid  latch  (2). 

Hounds.  Corner  plates. 

Assembling  bolts.  Angle  irons. 

Prop.  Tool  box. 

Foot-board.  Tool-box  latch. 

Floor.  Tool-box  straps  and  hinges. 

Bed.  Guard  plate. 

Bed-plate.  Lincu-pins  (2). 

Clamp  screws  (2).  Washers  (2). 

To  take  the  gun  apart. 

399*  1st.  Remove  the  locks. 

2d.  Remove  the  screws  and  take  off  the  cascable  plate. 

3d.  Remove  the  screw  from  the  end  of  the  crank  shaft  and 
take  off  tiie  oscillating  screw,  drive  out  the  steady-pin,  and  take 
out  crank  shaft,  worm,  and  sleeve. 

4th.  Remove  screw  from  rear  end  of  main  shaft  and  take  off 
worm  gear,  using  clamp  for  that  purpose. 

oth.  Take  off  brass  traversing  apparatus,  and  block  up  gun 
under  front  of  rear  plates. 

6th.  Take  out  screws  and  remove  hopper  and  breech-casing. 

7th.  Unscrew  screw  from  lock  cylinder,  back  out  steady-pin 
which  holds  the  rear  guide  nut,  and  remove  the  nut.  (The  nut 
works  on  a  left-hand  thread.) 

8th.  Take  off  lock  cylinder  and  carrier  block. 

To  remove  the  barrels  singly,  stand  the  cluster  muzzles  up, 
and  let  the  rear  end  of  the  main  shaft  strike  gently  on  a  block; 
the  shaft  and  front  plate  will  be  forced  off,  after  which  the  bar- 
rels may  be  unscrewed  with  a  socket- wrench. 

To  take  the  breech-casing  apart,  remove  the  screws  which 
hold  the  double  cam  to  the  diaphragm  and  slide  it  out  to  the 
front. 

To  assemble  the  gun. 

400.  1st.  Put  the  breech-casing  together;  screw  the  barrels 
into  the  rear  plate;  replace  the  front  plate  and  shaft;  insert  the 
front  end  of  the  shaft  into  the  socket  in  the  front  of  the  frame, 
and  rest  the  front  and  rear  plates  upon  blocks. 

2d.  Replace  the  carrier  blocks  and  lock  cylinder. 

3d.  Put  on  the  rear  guide  nut  and  put  in  steady-pin  and 
screw. 


182  HOTCHKISS   REVOLVING   GUN. 

4th.  Put  on  breech-casing  and  hopper  and  replace  the  screws. 

5th.  Put  on  the  brass  traversing  apparatus. 

6th.  Replace  worm  gear. 

7th.  Replace  worm  and  sleeve  and  insert  crank  shaft,  fasten- 
ing the  worm  in  its  place  with  the  steady-pin. 

8th.  Replace  oscillating  nut  and  set  screw. 

9th.  Replace  cascable  plate  and  screws. 

10th.  Replace  locks. 

In  taking  the  gun  apart,  it  will  be  found  much  more  conven- 
ient and  expeditious  to  first  remove  the  cascable  plate,  and  then 
the  locks  by  hand,  and  in  assembling  it  the}'  can  be  inserted  in 
the  same  manner  before  replacing  the  cascable  plate. 

When  the  lock  extractor  is  used,  the  breech  plug  is  turned 
horizontally;  the  crank  handle  is  turned  until  the  mark  upon 
the  rear  barrel  plate  and  the  arrow  on  the  hopper  coincide,  when 
the  lock  is  withdrawn. 


Hotchkiss  Revolving  Gun. 

The  Hotchkiss  revolving  gun  is  a  machine  gun  resembling 
in  exterior  aspect  the  Gatling  gun.  It  fires  explosive  shells, 
and  has  a  range  equal  to  modern  field  artillery. 

The  gun  consists  of  five  barrels,  grouped  around  a  common 
axis,  which  are  revolved  in  front  of  a  solid  immovable  breech 
block.  This  has  iu  one  part  an  opening  to  introduce  the  car- 
tridges, and  another  opening  through  which  to  extract  the  empty 
shells.  The  cartridges  are  discharged  singly  as  they  present 
themselves  by  the  rotary  motion  to  the  blow  of  the  firing-pin, 
and  while  motionless  in  front  of  the  solid  portion  of  the  breech. 

The  barrels  are  of  steel;  the  breech  block  is  of  cast-ir^n,  weigh- 
ing about  385  pounds.  This  absorbs  the  greater  part  of  the  re- 
coil. 

The  turning  of  a  crank  causes  the  automatic  loading,  firing, 
and  extraction  of  the  empty  cartridge-cases,  all  these  operations 
being  performed  continuously  during  the  movement  of  the  crank, 
the  peculiar  feature  being  that  the  barrels  remain  stationary  dur- 
ing the  discharge,  thus  insuring  accuracy  of  fire. 

The  cartridges  are  fed  through  a  trough  similar  to  the  case  of 
the  Gatling.  The  piece  can  be  accurately  aimed  and  fired  at  the 
rate  of  twenty  shots  per  minute ;  when  great  rapidity  is  required, 
this  may  be  increased  to  sixty  or  eighty. 

The  piece  is  served  by  the  same  number  of  men  and  in  a 
similar  manner  to  the  1-inch  Gatling. 

The  ammunition  consists  of  a  centre-fire  metallic  cartridge  of 


TARGET   PRACTICE. 


183 


special  construction,  holding  in  eacli  one  the  powder,  the  pro- 
jectile, and  the  lubricating- wad,  arranged  like  the  ammunition 
generally  used  for  small-arms.  Both  solid  shot  and  shell  arc 
used.  Solid  shot  made  of  steel  are  capable  of  penetrating  iron 
plating  of  one  inch  thickness  at  a  range  of  1000  yards.  The 
shell  is  of  cast-iron,  and  is  generally  fired  with  a  percussion-fuse. 

Calibre 1.457  inches. 

Length  of  bore 4.2  feet. 

Rifling,  one  turn  in M        4  feet. 

(Twist  and  depth  of  grooves  uniform.) 

Number  of  grooves 12 

Length  of  shell  with  fuse 3.C6  inches. 

Weight  of  shell  with  fuse 16.05  ounces. 

Charge  of  powder 4.3  ounces. 

Weight  of  complete  cartridge 25.04  ounces. 

Length  of  complete  cartridge 6.58  inches. 

Weight  of  piece 1047  pounds. 

Weight  of  carriage  complete 1092  pounds. 

Weight  of  limber 661  pouuds. 

Weight  of  460  rounds  of  ammunition 720  pounds. 

Total  weight 3561        pounds. 

The  carriage,  made  principally  of  steel,  is  of  peculiar  construc- 
tion, and  is  well  adapted  both  for  traveling  and  as  a  stable  sup- 
port for  the  piece  when  firing. 

Attached  to  the  frame  supporting  the  breech  block  and  bar- 
rels is  a  turn-table,  which  connects  the  cannon  to  a  trunnion- 
saddle,  arranged  in  such  manner  that,  without  displacing  the 
carriage,  a  certain  amount  of  lateral  motion  as  well  as  of  eleva- 
tion may  be  given  to  the  piece.  Thus  the  gun  is  made  to  sweep 
horizontally  along  a  line  by  adjustment  between  each  shot,  or 
during  rapid  discharge. 

In  addition  to  the  great  value  of  this  gun  for  light  field  ser- 
vice, it  is  peculiarly  well  adapted  to  field  intrenchments  and 
permanent  fortifications,  and  is  intended,  when  fully  introduced 
into  service,  to  replace  howitzers  for  flank  defenses. 

TARGET  PRACTICE. 

401.  Owing  to  the  great  expense  attending  target  practice 
with  artillery,  and  consequently  the  very  limited  quantity  of  am- 
munition allowed  for  it,  every  possible  means  should  be  taken  to 
secure  the  greatest  amount  of  instruction  that  can  be  had  from 
such  practice. 


184  TARGET    PRACTICE. 

The  purpose  should  be  to  lest,  from  actual  observation,  the 
effective  power  of  the  piece,  and  to  acquire  skill  in  utilizing  this 
power.  The  object  for  which  a  piece  is  placed  in  a  work  should 
be  studied,  and  practice  with  it  made  to  conform,  as  far  as  pos- 
sible, to  this  object. 

Siege  guns, 

402.  Siege  artillery  is  generally  used  against  fixed  objects  on 
land ;  the  target  should  therefore  be  placed  on  land. 

The  range  for  the  4.5"  gun  should  be  about  2000  yards,  and 
for  this  distance  a  target  12  feet  square  would  be  suitable.  It  is 
made  of  canvas,  or  of  light  boards  nailed  to  uprights  planted  in 
the  ground,  and  is  whitewashed.  A  circular  bull's-eye  4  feet  in 
diameter  is  painted  in  black  in  the  centre  of  the  target.  About 
100  feet  diagonally  in  front  of  the  target,  a  pit  of  suitable  size 
for  the  marker  is  dug,  the  earth  being  thrown  upon  the  side  to- 
wards the  piece.  It  adds  greatly  to  the  security  of  the  marker 
to  have  splinter-proof  covering  for  the  pit.  The  marker  is  pro- 
vided with  a  disk,  about  a  foot  in  diameter,  made  of  sheet-iron 
or  thin  board,  one  side  of  which  is  painted  black,  the  other  white, 
and  provided  with  a  staff  sufficiently  long  to  enable  him  to  point 
the  disk  to  any  part  of  the  target.  The  marker  should  be  accom- 
panied by  a  flagman  skilled  in  signaling,  and  provided  with  a 
white  or  red  flag,  such  as  are  supplied  by  the  Signal  Bureau. 
At  the  piece  is  another  flagman  similarly  provided.  Where  it  is 
possible,  a  hill,  situated  two  or  three  hundred  yards  beyond  the 
target,  is  advantageous  for  arresting  the  projectiles.  Cleared 
space  beyond  the  target  is  preferable  to  woods. 

Firm  ground  is  selected  for  the  gun  platform,  which  is  laid 
with  care  and  precision.  The  distance  to  the  target  is  ascer- 
tained either  by  direct  measurement,  with  the  telemeter,  or  by 
triangulation.  Previous  to  going  out  to  fire,  the  instructor 
should  prepare  a  memorandum  table  of  elevations  for  each  kind 
of  projectile  to  be  used,  and  the  time  to  which  fuses  are  to  be  cut 
for  shells.  The  time  of  flight  is  determined  by  means  of  a  stop- 
watch, and  the  distance  at  which  shells  burst  by  the  Boulonge* 
telemeter.  Care  and  deliberation  is  exercised  in  loading  and 
pointing.  When  the  piece  is  ready  to  be  fired,  a  signal  is  made 
by  the  flagman  at  the  piece  to  the  marker  and  flagman  at  the 
target,  who  then  screen  themselves  in  the  pit.*  As  soon  as  the 
projectile  strikes,  the  flagman  at  the  pit  raises  his  flag  and  the 
marker  proceeds,  in  case  it  has  struck  the  target,  to  cover  the 
hole  with  his  disk;  when  a  shell  has  been  fired,  the  flagman  sig- 
nals whether  it  has  burst  short  of  or  beyond  the  target.  An 
observer  at  the  piece,  with  a  glass,  or  even  with  the  naked  eye, 


TARGET    PRACTICE.  "  lHo 

cjin  see  upon  which  side  of  the  target  the  projectile  passes,  and 
can  form  an  approximate  estimate  of  the  distance  to  the  right  or 
left. 

From  the  data  thus  obtained,  errors  of  pointing  and  of  cutting 
the  fuse  may  be  corrected  for  succeeding  shots.  A  complete  rec- 
ord of  each  tire  is  kept  and  entered  on  a  blank  form  furnished 
by  the  Ordnance  Department.  This  record,  besides  giving  a  de- 
scription of  the  piece,  contains  the  kind  and  weight  of  the  pro- 
jectile, the  kind  of  powder  and  the  weight  of  charge,  the  eleva- 
tion and  the  time  of  flight,  the  kind  and  length  of  fuse,  and  the 
position  of  the  piece,  whether  above  or  below  the  level  of  the 
target.  In  the  column  of  remarks  is  entered  whether  the  pro- 
jectile struck  the  target,  and  if  so,  where;  or  if  it  missed,  to 
which  side,  and  how  far;  whether  it  fell  short  or  went  beyond  ; 
whether  the  shell  exploded  short,  beyond,  or  did  not  explode. 
The  direction  of  tiie  wind,  with  reference  to  the  line  of  fire,  and 
its  strength  are  noted. 

Those  engaged  in  the  firing,  particularly  the  officers,  should 
examine  and  study  the  ground  about  the  target,  observing  the 
effect  produced  by  the  striking  of  the  shot;  whether  they  pene- 
trated or  ricocheted ;  the  depth  of  penetration,  the  character  of 
the  abaters  formed  bjr  bursting  shells,  and  of  the  furrows  made 
by  glancing  projectiles.  This  information  is  useful  when  con- 
structing works  of  shelter  against  an  enemy,  aud  in  the  attack 
upon  and  demolition  of  his  works. 

When  the  allowance  of  ammunition  that  may  be  expended 
admits  of  it,  firing  at  a  horizontal  target  should  be  practiced. 
The  object  of  this  kind  of  firing  is  to  group  the  shots  as  closely 
as  possible  on  the  ground  about  the  target.  The  rectangular 
space  inclosed  by  the  shots  is  called  the  polygon  of  fire.  In 
actual  service,  the  purpose  of  such  fire  is  to  reach  an  enemy  shel- 
tered behind  works  or  some  intervening  object,  as  hills  or  woods. 
This  is  accomplished  by  the  drop  of  projectiles  fired  at  long 
range,  or  at  short  range  by  reducing  the  charge  and  giving  high 
elevation.  Skill  in  this,  the  most  difficult  kind  of  firing,  can  be 
acquired  only  by  practice. 

At  the  close  of  the  firing  the  piece  and  carriage  should  be 
thoroughly  inspected,  and  every  crack  or  breakage  noted  on  the 
firing  report.  For  the  method  of  inspection,  see  subject  of  In- 
spection. This  report  of  target  practice  is  general  for  all  artil- 
lery. 

To  obtain  the  centre  of  impact,  the  target,  if  an  upright  one, 
is  divided  into  four  parts  by  a  horizontal  and  a  vertical  line  pass- 
ing through  the  centre  of  the  bull's-eye ;  if  the  target  is  horizon- 
tal, as  for  mortar  firing,  one  line  is  drawn  as  the  trace  of  the 


186 


TARGET   PRACTICE. 


plane  of  fire,  and  the  other  through  the  centre  of  the  target  at 
right  angles  to  it. 

The  distance  in  feet  of  each  shot  is  measured  from  these  lines 
as  co-ordinates,  and  recorded  in  a  table;  as,  above  or  below  the 
horizontal  line,  and  to  the  right  or  left  of  the  vertical  line. 

The  table  is  of  the  following  form  : 


• 

i 

«o 

o 

• 

i 

1 

2 
3 
4 
5 

Distance  from  co-ordinates. 

Distance  from  centre  of 
impact. 

Vertical. 

Horizontal. 

Vertical. 

Horizontal. 

Above. 

Below. 

Right. 

Left. 

Aboye. 

Below. 

Right. 

Left. 

3 

4 

4 
6 

2 

2 
4 
3 

5 
2 

4 
5 

3 
5 

1 

i 

1.6 
3.6 
2.6 

5.4 
2.4 

7 

12 

9 

7 

9 

9 

7.8 

7.8 

5-j-5=l 

2-1-5=0.4 

18-f-o=3.6 

15.6-^-5=3.12 

The  algebraic  sum  of  the  distances  in  each  direction,  divided 
by  the  number  of  shots,  gives  the  position  of  the  centre  of  im- 
pact in  this  direction.  In  the  above  example,  the  position  of  the 
centre  of  impact  is  1  foot  below  and  0.4  of  a  foot  to  the  right  of 
the  centre  of  the  target. 

To  obtain  the  mean  deviation,  it  is  necessary  to  refer  each  shot- 
hole  to  the  centre  of  impact  as  a  new  origin  of  co-ordinates ;  and 
this  is  done  by  subtracting  the  tabular  distance  from  the  distance 
of  the  centre  of  impact,  if  both  be  on  the  same  s'ute  of  the  centre 
of  the  target,  and  adding  them,  if  on  different  sides.  The  sum 
of  all  the  distances  thus  obtained  in  one  direction,  divided  by  the 
number  of  shots,  gives  the  mean  deviation  in  that  direction  ; 
which  in  the  present  case  is  3.6  feet  vertically,  and  3.15  feet  hori- 
zontally. 

The  foregoing  affords  a  measure  for  the  accuracy  of  fire  of  the 


TARGET   PRACTICE.  187 

piece  and  projectile,  but  it  does  not  afford  so  good  a  tost  of  marks- 
manship as  the  string,  or  sum  of  the  distances  of  the  shots  from 
the  point  aimed  at. 

When  practicable,  epaulments  are  constructed  for  siege  gunsr 
howitzers,  and  mortars. 

Siege  howitzer. 

403.  Target  practice  with  the  8-inch  siege  howitzer  is  con- 
ducted in  the  same  manner  as  for  6iege  guns,  but  the  distance 
should  not  exceed  1200  yards,  and  the  target  need  not  be  over 
10  feet  square. 

Direct,  ricochet,  and  rolling  tire  should  each  be  practiced  with 
this  piece.  To  observe  the  flight  of  canister,  it  is  best  to  fire  it 
over  smooth  water,  with  an  elevation  not  exceeding  two  degrees- 

10-incA  siege  mortar. 

404.  The  target  for  the  10-inch  siege  mortar  should  be  about 
1500  yards  from  the  piece.  The  best  form  for  the  target  is  that 
of  a  square,  inclosing  the  general  trace  of  a  field- work.  The 
sides  of  the  square  should  be  about  100  yards,  and  the  trace 
marked  by  stakes  driven  at  distances  of  about  10  feet  apart. 

A  large  empty  cask  or  box,  placed  upon  a  post  in  the  centre 
of  the  figure,  and  whitewashed,  serves  as  a  point  to  aim  at. 

At  a  distance  of  not  less  than  150  5Tards  to  the  right  or  left  of 
the  target,  is  constructed  a  strong  bomb-proof  for  the  marker 
and  flagman. 

The  marker  is  provided  with  a  number  of  small  stakes,  which,, 
to  make  them  more  conspicuous,  have  attached  to  them  a  piece 
of  white  or  red  stuff.  When  a  shell  strikes  the  ground,  the 
marker  notes  the  place  with  a  stake,  marking  it  with  a  number 
corresponding  to  the  number  of  the  shot.  The  rules  governing 
the  flagman  at  the  bomb-proof  and  at  the  piece  are  the  same  as 
those  already  given  for  the  siege  gun. 

A  convenient  method  of  notifying  those  at  the  mortar  as  to  the 
points  at  which  the  shells  strike,  is  to  describe  around  the  centre 
of  the  target  a  circle  with  a  radius  of  about  twenty^five  yards. 
Divide  this  circle  into  twelve  equal  parts,  which  mark  conspicu- 
ously with  stakes,  being  careful  to  place  one  of  the  divisions  on 
the  prolongation  of  the  line  passing  through  the  mortar  and  the 
centre  of  the  target.  Call  this  point  XII,  and  number  the  others 
around  to  the  right  similar  to  the  dial  of  a  clock. 

Suppose  the  shell  falls  at  the  point  C,  (Fig.  1,  Plate  15,)  on 
the  line  passing  through  the  centre  B  and  I,  and  at  a  distance  of 
say  twenty  yards  from  the  centre.  The  marker  steps,  or  other- 
wise measures  this  distance,  and  signals  to  the  piece  4k  One" — 


188  TARGET   PRACTICE. 


«c 


20."  Those  at  the  piece,  referring  to  a  similar  diagram  made 
upon  diagram  paper,  ascertain  at  a  glance  the  approximate 
point  at  which  the  shell  struck  the  ground. 

Firm  ground  is  selected  for  the  platform,  and  the  distance  to 
the  target  is  determined  as  for  siege  guns,  as  is  likewise  the  time 
of  flight  of  shells  and  the  distance  at  which  they  explode. 

In  order  to  economize  shells,  charges  sufficient  only  to  blow 
out  the  fuse  are  used,  and  the  shells  are  afterwards  collected. 

After  the  firing  is  completed,  the  distance  from  each  point 
where  a  shell  fell  to  the  centre  of  the  target  is  measured,  and,  if 
-desirable,  a  diagram  made  of  the  target,  showing  the  position  of 
-each  shot. 

Previous  to  going  out  to  fire,  the  instructor  should  prepare  a 
memorandum  range  table,  so  that  the  first  shots  may  be  approx- 
imately accurate.  Subsequent  shots  should  be  rectified  with 
care ;  the  tendency  is  always  to  overdo  the  correction ;  as,  for 
instance,  when  the  shell  falls  short,  the  addition  given  to  the 
•charge  will  most  likely  send  it  far  beyond ;  or,  should  it  fall  to 
one  side,  the  correction  given  to  the  direction  will  probably  be 
so  great  as  to  cause  it  to  fall  a  still  greater  distance  to  the  other 
side.  Under  the  most  favorable  circumstances,  mortar  firing,  as 
compared  with  firing  from  other  kinds  of  cannon,  possesses,  in- 
herently, a  considerable  degree  of  inaccuracy,  and  in  making 
■corrections  care  should  be  observed  to  discriminate  between  this 
and  faulty  gunnery. 

When  practicable,  the  charges  of  powder  should  be  weighed ; 
if  measured^  uniformity  should  be  observed  as  to  the  manner  of 
doing  it,  so  that  all  shall  be  shaken  down  in  the  measure,  or  all 
measured  loosely. 

The  platform  should  be  tested  frequently,  to  see  that  it  does 
not  settle  unevenly.  The  shells  should  be  weighed  and  marked 
with  chalk,  and  in  firing  them  care  should  be  observed  to  com- 
mence with  the  lightest  and  go  up  to  the  heaviest,  or  vice  versa. 
This  enables  the  corresponding  variation  of  the  charge  to  be  made 
with  a  greater  degree  of  certainty.  In  all  cases  of  target  prac- 
tice a  complete  record  is  kept  for  each  shot,  and  a  report,  as 
heretofore  explained  for  siege  guns,  is  made. 

8-inch  mortar, 

405*  Target  practice  with  the  8-inch  mortar  is  conducted  as 

just  explained  for  the  10-inch. 

Coehorn  mortar. 

406*  Target  practice  with  this  piece  is  similar  to  the  fore- 
going; but  the  distance  to  the  target  should  not  exceed  1000 


TAKGET   PRACTICE.  18l> 

yards,  and  the  target  may  be  smaller.  As  this  piece  can  be 
moved  from  place  to  place  with  ease,  and  requires  nothing  more 
than  level  and  firm  ground  for  a  platform,  the  distance  to  the 
target  should  be  varied,  thus  affording  practice  such  as  fre- 
quently occurs  in  war  service. 

Sear-coast  mortars, 

(13-mc/t.) 

407*  These  mortars  are  chiefly  used  against  shipping,  in  the 
defense  of  harbors;  a  floating  target  should  therefore  be  used. 
Any  floating  object,  as  an  empty  cask  or  a  spar,  anchored  to 
mark  the  spot,  suffices. 

The  distance  to  the  target  should  be  about  3000  yards.  The 
practice  is  conducted  in  the  same  manner  as  for  the  10-inch  siege 
mortar,  except  that  for  the  purpose  of  determining  the  points  of 
fall,  or  of  explosion  of  the  shells,  plane-tables  are  employed  in 
the  manner  hereafter  explained.  As  the  shells  are  not  recov- 
ered after  being  fired,  bursting  charges  may  be  used. 

(10-inch.) 

408.  Target  practice  with  this  piece  is  identical  with  that  for 
the  13-inch  mortar. 

Sea-coast  guns. 

409.  As  this  class  of  guns  are  chiefly  used  against  ships,  and 
are  fired  over  water,  the  target  should  be  floating. 

For  the  15-inch  smooth-bore  and  the  8-inch  and  Parrott  rifles, 
it  should  be  moored  at  a  distance  of  about  3000  yards;  for  the 
10-inch  smooth-bore,  the  distance  should  be  about  2000  yards. 

Plane-tables  (Fig.  2,  Plate  15)  are  employed  for  the  purpose 
of  recording  the  striking  points  of  shots,  or  the  bursting  distance 
of  shells.  The  tables  are  stationed,  one  at  each  extremity  of  a 
line,  the  length  of  which  is  accurately  determined  either  by  act- 
ual measurement  or  by  triangulatiou  from  a  base-line,  the  meas- 
urement of  which  has  been  made  with  care  and  precision. 

At  every  post  mounting  heavy  artillery  a  base-line  should  be 
so  determined  and  permanently  marked,  to  be  used  for  the  vari- 
ous requirements  of  artillery  firing.     About  1000  yards  is  a  suit- 
ble  length  for  it. 

The  plane-tables  are  placed  so  as  to  have  a  clear  view  of  the 
arget,  of  each  other,  and  of  the  guns.  They  should,  further- 
more, be  so  placed  that  the  lines  joining  them  with  the  target 
vill  intersect  at  as  near  a  right  angle  as  possible.  This  enables 
he  position  of  the  shot  to  be  determined  and  plotted  with  greater 


190  TARGET   PRACTICE. 

accuracy  than  would  be  the  case  did  the  lines  intersect  with  a 
very  acute  angle. 

Floating  Target.  {Fig.  3,  Plate  15.)  The  best  and  most 
readily  constructed  target  is  composed  of  three  stout  boards 
twelve  feet  long  and  a  foot  broad,  forming  a  triangle.  A  fourth 
board  extends  from  one  of  the  angles  to  the  middle  of  the  oppo- 
site side.  The  whole  is  fastened  together  with  spikes,  or,  better, 
with  screw  bolts. 

At  the  centre  of  the  triangle,  a  hole  is  cut  in  the  last-mentioned 
board;  this  hole  is  about  four  inches  in  diameter;  through  it 
passes  a  pole  projecting  about  twelve  feet  above  and  three  feet 
below. 

A  10-inch  shot,  or  equivalent  weight,  is  secured  to  the  lower 
■end  of  the  pole,  and  rope  guys  are  led  from  the  top  to  the  angles 
of  the  platform  to  keep  the  pole  upright.  To  these  ropes  are 
fastened  triangular  pieces  of  canvas.  A  bull's-eye  four  feet  in 
diameter  Is  painted  on  the  middle  of  this  screen,  upon  each  side. 
On  each  side  of  the  pole,  underneath  the  platform,  an  empty 
water-tight  barrel  is  lashed  to  the  athwart-board,  and  a  small 
red  flag  is  placed  on  the  top  of  the  pole. 

This  target  is  suitable  for  even  the  roughest  water.  To  hold 
it,  under  such  circumstances,  requires  an  anchor  weighing  not 
less  than  200  pounds.  This  is  attached  to  the  target  by  a  chain 
or  heavy  rope,  secured  to  one  angle  of  the  base  by  an  eye  on  the 
under  end  of  the  bolt  holding  the  planks  together.' 

When  a  single  anchor  is  used,  the  chain  or  rope  is  liable  to 
wind  itself  around  and  trip  the  anchor,  causing  it  to  drag.  To 
obviate  this,  it  is  advisable  to  moor  the  target  with  two  anchors, 
placed  in  the  direction  of  the  current.  The  distance  of  the 
anchors  apart  must  depend  upon  the  depth  of  the  water,  and 
should  be  such  as  to  form,  with  the  moori tig-chains,  about  an 
equilateral  triangle. 

Figure  4,  Plate  15,  shows  the  construction  of  a  target  fre- 
quently used  in  smooth  water. 

An  empty  water-tight  cask,  painted  some  dark  color,  forms  a 
good  target  or  point  at  which  to  aim.  The  cask  is  secured  in 
position  by  means  of  a  small  anchor  or  kedge  attached  to  it  by 
a  stout  rope  fastened  to  secure  lashings  on  the  cask.  Instead  of 
an  anchor,  any  heavy  body,  such  as  a  stone  or  bars  of  iron,  may 
be  used.  If  the  current  is  swift,  the  weight  should  not  be  less 
than  the  flotation  of  the  cask.  This  latter  is  obtained  by  multi- 
plying the  number  of  gallons  contained  in  the  cask  by  ten — the 
.approximate  weight  of  a  gallon  of  water. 

A  spar,  similar  to  the  spar  buoys  to  be  seen  about  harbors, 
forms  a  good  target  and  one  of  easy  construction.    When  a  spar 


TARGET   PRACTICE.  VJ1 

or  cask  is  used,  a  small  flag  of  some  bright-colored  stuff,  attached 
to  the  target,  makes  it  more  conspicuous  and  easy  to  aim  at. 

The  target  is  moored  in  position  at  the  commencement  of  the 
season's  firing,  and  is  left  out  until  the  firing  is  completed.  Its 
distance  from  the  two  stations  and  from  the  gun  is  determined 
by  ordinary  trigonometrical  methods,  or  by  plotting  from  plane- 
table  observations. 

The  plane-tables  are  the  ordinary  instruments  described  in 
works  on  surveying. 

After  the  table  is  set  up  at  its  station  and  adjusted,  the  officer 
in  charge  marks  upon  it  the  line  to  the  target,  to  the  gun,  and 
to  the  other  station.  These  lines  form  the  basis  for  the  subse- 
quent plotting  of  the  shots. 

The  officer  at  each  station  is  accompanied  by  a  flagman  to 
signal  to  the  piece  whether  tiie  shots  are  sliort*  or  over.  By  tills 
means  the  error,  for  subsequent  shots,  is  approximately  corrected. 

The  officer  in  charge  of  the  firing  attends  to  the  loading  and 
aiming,  sees  that  the  charges  and  projectiles  are  weighed,  and 
that  the  pressure  plug  (when  used)  is  properly  attached  to  the 
cartridge ;  also  that  the  fuses  for  the  shells  are  of  the  proper 
length.  When  everything  is  in  readiness,  he  directs  his  signal 
flag  to  be  raised  to  inform  the  observers  at  the  stations  that  he 
is  about  to  fire.  The  piece  is  then  discharged.  The  other  of- 
ficers at  the  battery  attend  to  the  stop-watch  and  telemeter. 

When  the  gun  is  fired,  the  officer  at  each  station,  sighting 
through  the  alidade,  catches  the  point  on  the  water  where  the 
shot  strikes,  or,  in  case  of  a  shell,  the  point  in  the  air  where  it 
explodes.  He  then  draws  a  fine  line  to  mark  the  direction,  and 
gives  it  a  number  corresponding  with  the  number  of  the  shot. 

The  observations  thus  obtained  are  plotted.  A  suitable  scale 
is  assumed,  (one  of  one  inch  to  100  yards  is  convenient,)  and  the 
line  joining  the  two  stations  is  laid  off  on  the  plotting  sheet  ac- 
cording to  the  scale.  From  this  all  the  other  lines  are  laid  off, 
usually  by  the  method  of  chords.  The  intersection  of  the  lines 
to  the  target  establishes  its  position,  and  those  to  the  gun  its 
position  also.  The  distance  from  the  gun  to  the  target  is  ascer- 
tained from  the  scale.  The  lines  of  observation  to  each  shot 
having  been  carefully  numbered  by  the  observers  at  the  plane- 
tables,  the  intersection  of  corresponding  numbers  on  the  plot 
give  the  striking  points  of  the  shots,  or  bursting  points  of  the 
shells. 

When  plane-tables  are  not  to  be  had,  any  instruments  gradu- 
ated for  measuring  angles  and  provided  with  sights  through 
which  the  shots  can  be  observed,  may  be  used,  and  the  work 
accomplished  as  just  described.    An  observer  at  the  piece  takes 


192  TELEMETERS. 

the  time  of  flight  with  a  stop-watch,  and  another  observer  ob- 
tains the  bursting  distance  of  shells  with  the  Boulongi  telemeter. 

The  direction  of  the  wind  is  determined  by  a  vane  at  the  piece. 
The  most  convenient  and  reliable  method  of  noting  it  is  by  refer- 
ring it  to  the  dial  of  a  watch  held  in  such  a  position  that  the  line 
passing  through  VI  and  XII  will  be  parallel  to  the  line  of  fire 
with  the  XII  towards  the  target.  The  direction  is  that  from 
which  the  wind  comes.  When  coming  directly  from  the  front, 
it  is  noted  as  "twelve  o'clock";  when  from  the  rear,  as  "six 
o'clock"  ;  when  from  the  right,  as  "three  o'clock" ;  when  from 
the  left,  as  "nine  o1 clock"  ;  and  when  from  intermediate  points, 
in  a  similar  manner. 

The  velocity  of  the  wind  is  determined  by  an  anemometer; 
but  as  this  instrument  is  seldom  to  be  found  at  military  posts, 
the  best  that  can  be  done  is  to  estimate  the  velocity,  and  record 
it  as  explained  in  par,  204. 

When  it  is  practicable  to  establish  telegraphic  communication, 
all  of  the  foregoing  operations,  so  far  as  signaling  is  concerned, 
are  greatly  facilitated. 

Gatling  gxtn. 

410.  The  target  for  this  gun  is  made  of  light  canvas  or  ordi- 
nary muslin,  and  is  in  four  or  more  sections,  each  section  being 
8  feet  long  by  6  feet  high.  The  canvas  is  nailed  to  a  strong 
light  frame,  the  uprights  of  which  extend  about  12  inches  below 
the  canvas,  in  order  that  they  may  be  set  in  the  ground. 

Practice  should  commence  at  200  yards  and  the  distance  be 
increased  up  to  1000  yards,  or  more.  At  the  first  distance  a  single 
section  of  the  target  is  sufficient,  and,  as  the  distance  increases, 
other  sections  will  be  added.  Smooth,  level,  aud  firm  ground 
should  be  selected  for  the  gun  to  stand  upon. 

Telemeters. 

411*  The  Boulongi  telemeter  is  an  instrument  devised  for  as- 
certaining the  distance  to  a  point  by  means  of  sound  proceeding 
from  the  point  to  the  place  of  observation.  The  one  used  for 
artillery  purposes  consists  of  a  glass  tube  about  six  inches  in 
length,  filled  with  a  transparent  liquid  that  does  not  freeze  ex- 
cept with  intense  cold.    (Fig.  1,  Plate  16.) 

In  the  liquid  is  a  metallic  disk,  which  moves  freely  from  one 
end  of  the  tube  to  the  other.  It  is  so  adjusted  that  the  motion 
will  be  uniform  and  comparatively  slow.  The  tube  is  inclosed 
in  a  brass  case,  to  which  is  attached  a  scale,  after  the  fashion  of 


ids 

a  thermometer.  IMs  seals  fs  marked  for  each  hundred  yards 
up  to  4000. 

The  divisions  on  the  scale  show  the  distance,  in  yards,  through 
which  sound  will  travel  in  air,  during  the  time  required  for  the 
disk  to  descend  over  the  space  on  the  scale  marked  by  the  corre- 
sponding number  of  yards.  If,  for  Instance,  the  disk  passes 
from  zero  to  the  900  mark,  it  indicates  that  sound  would  have 
traveled  500  yards  through  the  air  during  that  time. 

The  instrument  must  be  held  vertically,  or  us  nearly  so  as  pos- 
sible. To  arrest  the  motion  of  the  disk  at  any  point,  the  instru- 
ment is  quickly  turned  to  a  horizontal  position. 

To  use  it  for  determining  the  time  of  flight  of  shells.  It  is  held 
in  the  right  hand,  back  of  the  hand  up,  with  the  zero  of  the  in- 
strument to  the  left;  a  turn  of  the  wrist  to  the  right  brings  the 
instrument  vertical,  with  the  zero  end  uppermost ;  the  disk  then 
descends,  and  a  turn  of  the  wrist  to  the  left  arrests  its  motion. 
The  observer,  holding  the  instrument  as  described,  watches  for 
the  flash  of  the  shell,  and  upon  seeing  it,  instantly  brings  the 
instrument  to  a  vertical  position ;  upon  hearing  the  report  from 
the  shell,  he  instantly  turns  it  back  again.  The  position  of  the 
disk  indicates  the  number  of  yards  from  the  observer  to  where 
the  shell  exploded. 

To  ascertain  the  distance  to  an  enemy's  battery,  the  instru- 
ment is  held  and  turned  in  the  same  manner.  The  observer 
watches  for  the  flash  of  a  gun ;  observiug  which,  lie  turns  the 
instrument,  and,  when  he  hears  the  report,  turns  it  back  and 
reads  off  tlie  distance.  Each  hundred  yards  on  the  scale  is  sub- 
divided into  quarters. 

412.  The  telemeter  invented  by  Captain  A.  Gautler,  of  the 
French  army,  is  an  instrument  for  measuring,  with  a  great  degree 
of  approximation,  any  difference,  not  exceeding  three  degrees, 
whicli  may  be  exhibited  in  the  bearing  of  a  distant  object  by 
viewing  it  from  different  points  of  a  base-line  transverse  to  its 
general  direction  from  the  observer. 

The  instrument,  in  its  simplicity,  accuracy,  and  portability, 
recommends  itself  in  all  cases  where  a  knowledge  of  distances  is 
desired  at  any  moment  and  with  the  least  possible  delay ;  such, 
for  instance,  as  range-flndmg,  river-crossing,  reconnoiteri ng,  and 
the  Kfce.  A  slight  acquaintance  with  its  use  on  such  occasions 
enables  the  observer  to  estimate,  with  more  than  ordinary 

gvompfcitucte  and  precision,  the  distance  which  it  might  be  all 
Dportant  to  obtain. 

The  principles  of  this  instrument  are  explained  mathematically 
ittQrdimow  Memoranda  No.  12. 
The  instrument  (Fig.  2,  Plate  16)  resembles  in  shape  and  Sf2e 
13 


194  TELEMETERS. 

one  barrel  of  an  ordinary  reconnoiteriug  or  field-glass.  The  case 
in  which  it  is  carried  is  fashioned  so  as  to  answer  as  a  handle  for 
holding  the  instrument  when  making  observations.  (Fig.  3, 
Plate  16.) 

Within  the  barrel  of  the  instrument  are  placed  two  mirrors  at 
an  angle  of  about  45  degrees  with  each  other;  this  angle  can 
be  varied  within  certain  limits  by  means  of  a  railled-hcaded 
screw  acting  on  one  of  them.  The  mirrors  are  thus  made  to 
operate  upon  the  principle  of  the  sextant.  A  slot  on  one  side  of 
the  barrel  permits  the  rays  of  light  from  an  object  to  fall  upon 
one  of  the  mirrors,  from  whence  they  are  reflected  upon  the  other 
mirror,  and  the  image  is  seen  through  the  eye-glass  at  the  small 
end  of  the  instrument. 

At  the  front  or  large  end  is  fixed,  in  a  ring  surrounding  the 
barrel,  a  prism,  whose  displacement  modifies  the  direction  of  an 
object  seen  through  it. 

At  the  rear  of  the  instrument  is  a  small  eye-glass,  by  means  of 
which  the  observer  sees,  over  the  mirrors  and  through  the  prism, 
the  object  which  is  before  him,  and  by  double  reflection  in  the 
mirrors  the  object  to  the  side  of  him. 

The  semi-revolution  of  the  movable  ring  containing  the  prism 
corresponds  to  a  displacement  of  the  object  toward  the  left  of 
about  three  degrees.  The  ring  is  provided  with  a  graduated  scale 
containing  numbers,  the  use  of  which  will  be  explained. 

Method  of  using  the  instrument. 

Suppose  C  (Fig.  4,  Plate  16)  to  be  the  object  and  A  the  point 
from  which  the  distance  A  C  is  to  be  determined. 

Select  some  distant  object,  as  M,  for  a  signal,  the  direction  A 
M  to  it  making  with  the  line  A  C  an  angle  a  little  greater  than 
90  degrees.  From  the  point  A  measure  a  base,  A  B,  in  prolon- 
gation of  the  line  to  the  signal. 

After  having  adjusted  the  telemeter  upon  the  case,  which 
serves  as  a  vertical  handle,  turn  the  ring  until  the  word  "infin- 
ity "  is  brought  opposite  the  fixed  index  or  arrow.  This  brings 
the  prism  to  its  initial  position. 

A  small  opening  in  the  under  part  of  the  instrument,  exhibit- 
ing the  mirror  index,  enables  the  observer  to  assure  himself  that 
the  movable  mirror  is  at  its  mean  position,  which  is  indicated  by 
a  fixed  mark. 

The  telemeter  is  then  ready  for  operation,  and  the  observer 
places  himself  at  A,  so  that  the  object  C  will  be  on  his  right. 
(The  right  is  here  chosen  merely  for  purpose  of  illustration. 
The  observation  can  be  as  easily  made  with  the  object  on  the 
left.) 


TXLBMBTBR8.  195 

The  Instrument  |g  held  in  the  left  hand,  the  fingers  of  which 
•clasp  the  barrel  firmly  to  the  handle  (the  case).  The  observer, 
facing  the  signal  H  and  sighting  through  the  eye-glass  upon  the 
signal,  turns,  with  the  right  hand,  the  milled  screw  until  the 
image  of  the  object  C  coincides  with  the  signal  M.  Leaving  the 
screw  in  this  position,  he  retires  to  the  other  end,  B,  of  the  base- 
line, where,  holding  the  instrument  as  before,  he  sights  upon 
the  signal,  and  turning  the  graduated  ring  on  the  front  end, 
makes  the  images  again  coincide.  This  done,  there  will  be 
found  on  the  ring  opposite  the  fixed  index  a  number,  which, 
being  multiplied  by  the  number  of  units  in  the  base-line,  will 
give  the  required  distance  A  C  in  terms  of  the  unit  used  in 
measuring  the  base. 

This  is  the  method  of  a  fixed  base.  Another  method  is  by 
means  of  a  proportional  base,  which  is,  instead  of  measuring  a 
base  as  Just  described,  a  certain  factor  is  selected  on  the  ring 
and  the  instrument  set  to  it ;  then  by  moving  back  in  the  direc- 
tion A  B  until  the  images  coincide,  the  distance  thus  moved  over 
will  be  the  base,  which  is  then  measured  and  multiplied  by  the 
selected  factor.  This  method  has  the  advantage  of  eliminating 
the  errors  of  reading  the  movable  ring. 

A  base  of  jfo  of  the  distance  suffices  in  general  for  obtaining 
the  exactness  of  measurement  required  in  military  operations. 
It  is  necessary  always  that  the  object  and  the  signal  be  well  de- 
fined and  of  a  convenient  form  and  size,  and  that  the  observer 
be  sufficiently  skilled  with  the  instrument  to  make  with  precis- 
ion the  necessary  sightings,  and  to  make  the  proper  alignment 
of  the  two  stations  upon  the  signal.  In  a  case  where  a  good 
natural  signal  is  found,  distances  up  to  2000  meters  can  be  read- 
fly  measured  in  less  than  two  minutes.  If  the  conditions  are 
less  favorable,  the  measurements  may  be  effected  by  employing 
bases  of  -fa  or  of  fo.  Whatever  be  the  method  employed,  the 
immediate  result  of  the  operation  is  the  knowledge  of  the  rela- 
tion between  the  distance  sought  and  the  base.  The  base  may 
be  expressed  according  to  any  unit  of  measurement,  and  the  dis- 
tance will  be  correspondingly  expressed.  If  the  base  is  measured 
in  yards,  the  distance  will  be  yards,  <fcc. 

A  good  natural  signal  is  one  which  best  satisfies  the  following 
conditions,  viz.:  Perfectly  visible ;  form  well  defined  and  sym- 
metrical, with  reference  to  a  vertical  axis ;  distance  very  great 
in  proportion  to  the  length  of  base  we  wish  to  use ;  height  at 
least  yJu  of  its  distance  from  us;  direction,  making  with  that  of 
the  object,  an  angle  a  little  greater  than  90  degrees.  In  case  no 
convenient  natural  signal  can  be  found,  its  place  may  be  arti- 


itfaUy  sngpUftl  fegr  an  «M  placiqg  himself  at  8QQ*r  800  antler* 
distant  and  holing  Inmself  InMnovabJe. 

An  operator  who  thoroughly  comprehend*  tbe  principle  of 
the  tetemejtef  wijl  fa  9,  short  time  acquire  auffleient  skill  to  use 
it  to  the  best  advantage.  £e  will  discover  that  the  ehoiee  of  the 
Bignal  ha?  a. great  influent  00  th#  accuracy  of  the  operation; 
he  will  judge  oj  the  amount  0$  care,  necessary  in  sewing  align- 
ment of  the  stations;  and,  in.  fine,  he  will  be  able  to, modify  or 
perfect,  according  to  circumstance**  the  processes  heretofore 
indicated. 

The  choice  of  the  signal  i%  a  pwot  very  important  to  the  pne- 
cisipu  of  sighting.  II  the  object  and,  the  signal  aire  each  sym- 
metrical with  reference  to  a  vertical  axis,  and  of  a  height  at 
least  sfo  of  their  distance  from  the  observer,  and  upon  nearly 
level  ground,  the  sighting  can  be  made  to  within  2"  or  3"; 
while  if  the  signal  is  but  barely  visible,  or  ol  little  height,  or  of 
vague  form.,  errors  up  to  2'  may  be  committed.  It  is  seen, 
therefore*  tha£  of  two  natural  signal?  unequally  distant  from 
the  observer,  the  nearest  may  be  the  more  advantageous ;  but 
of  this,  experience  will  be  the  best  guide  of  the  observer. 

The  alignment  of  the  two  stations  can  be  made  in  several 
different  manner  according  to  require mentis*  The  operator 
can  tajce  before  him  tvvo  natural  objects,  the  first  near  and  the 
second,  sufficiently  far  of,  very  distinct,  and  high  enough  not 
to  be  masked  by  the  first.  It  is  always  of  advantage  to  use  a 
stake  at  tjhe  first  station  not  high  enough  to  obscure,  the  signal ; 
and  this  precaution  is  the  more  necessary  if  the  signal  is  feuj;  a 
short  distance  off. 

The  instrument  gives  a  very  simple  means  of  knowing  whether 
the  position  of  the  second  station  is  well  chosen.  After  having 
established  the  coincidence  between  the  reflected  object  and  th$ 
signal  at  the  second  station,  the  front  of  the  Instrument  should 
be  lowered  perpendicularly,  so  as.  to  take  in  the  point  of  first 
observation.  Tbis  point  should,  if  the  second  station  is  correct* 
appear  in  coincidence  with  the  reflected,  object. 

The  operation  can  be  performed  by  either  facing  the.  signal  or 
facing  the  object.  The  first  method,  is  always  preferable,  a& 
the  latter  necessitates  the  taking  of  the  base  to  the  side,  which 
renders  alignment  more  difficult.  Nevertheless,  if  the  object 
be  indistiuot  or  difficult  to  distinguish  from  its  surroundings,  ifc 
may  be  regarded  by  the  second  method,  care  being  taken  at  tb& 
second  station  that  the  instrument  is  turned,  a  Mttto  on  its  own 
axis,  so  as  tp  take  in  the  petn&  oj  tot.  observation,  a&4  thai 


PRESSURE  PLUG.  197 

point  be  found  to  He  in  the  same  vertical  plane  with  the  natural 
signal. 

Pressure  Plug. 

413*  Rodman's  pressure  plug  (Fig.  5,  Plate  16)  is  used  when 
it  is  desired  to  ascertain  the  pressure  per  square  inch  exerted  by 
the  powder  on  the  surface  of  the  bore  of  a  piece.  To  apply  this 
instrument,  it  is  first  taken  apart  by  unscrewing  the  cap  and 
removing  the  piston  and  disk  containing  the  knife.  The  whole 
is  then  thoroughly  oiled  with  sperm  oil.  This  done,  place  a  cop- 
per disk  in  the  ping,  and  after  it  the  disk  containing  the  knife, 
the  latter  being  slid  down  so  as  not  to  cut  the  copper  disk.  Next 
pass  the  piston  into  the  hole  in  ttie  stem  of  ttie  cap,  and  screw 
the  cap  into  its  place.  For  this  operation  the  plug  is  held  hori- 
zontally in  a  vise.  A  small  copper  gas-check  is  then  inserted 
into  the  hole  on  top  of  the  piston ;  a  wooden  drift  is  used  to 
set  the  gas-check  firmly  in  its  place,  and  a  small  wad  of  cotton- 
waste  is  inserted  over  the  gas-check ;  the  plug  is  now  put  into 
the  empty  cartridge-bag,  with  its  grooved  end  at  the  bottom  and 
centre  of  the  bag,  and  the  bag  tied  firmly  to  it  from  the  outside, 
with  twine  passing  around  the  grooves  on  the*  bottom  of  the 
plug.  The  powder  is  next  put  in,  care  being  taken  to  distrib- 
ute it  evenly  around  the  plug.  The  bag  is  tied  close  to  the  pow- 
der so  as  to  make  the  cartridge  firm  and  compact. 

When  inserting  the  cartridge  into  the  gun,  care  is  taken  that 
the  plug,  when  at  the  bottom  of  the  bore,  is,  as  nearly  as  possi- 
ble, in  the  axis  of  the  piece. 

After  the  discharge,  the  plug  is  removed  from  the  bore  by  a 
rake  made  for  the  purpose ;  the  cap  is  unscrewed,  the  copper 
disk  removed,  and,  after  being  wiped,  the  cut  made  upon  it  by 
the  knife  is  measured,  from  end  to  end,  with  a  pair  of  dividers. 
The  dividers  are  then  applied  to  the  scale  and  passed  down  the 
two  long  lines  until  they  intersect  a  cross  line  the  length  of 
which  corresponds  to  the  width  of  the  dividers ;  the  figures  at 
this  point  indicate  the  number  of  pounds  pressure  to  the  square 
Inch. 

Pressure  plugs  are  of  three  sizes:  one  for  the  12-inch  rifle 
and  13-inch  and  15-inch  smooth-bores ;  oue  for  the  100-pounder 
Parrott  rifle  and  8-inch  and  10-inch  smooth-bores ;  and  one  for 
smaller  calibres. 


fart  Sftirl 


MECHANICAL    MANOEUVRES. 

General  Directions, 

414.  The  mechanical  manoeuvres  are  the  application  of  ma- 
chines and  of  mechanical  powers  for  mounting,  dismounting, 
moving,  and  transporting  artillery. 

415.  The  detachment  for  mechanical  manoeuvres  consists  of 
one  chief-of-detachment,  one  gunner,  and  ten  cannoneers.  It  is 
formed  as  in  par,  14;  marched  to  the  place  of  exercise  as  in  par. 
106, and  takes  post  as  in  par.  107,  except  that  the  cannoneers  are 
posted  two  yards  from  the  axis  of  the  piece  or  carriage ;  Nos.  1 
and  2  opposite  the  muzzle  or  front  part  of  the  carriage,  the  other 
numbers  and  the  gunner  dressing  on  Nos.  1  and  2,  respectively, 
at  intervals  of  one  yard,  except  between  Nos.  3  and  5,  where 
there  is  an  interval  of  two  yards.  All  face  towards  the  piece  or 
carriage. 

The  cannoneers  change  posts  as  in  par.  112. 

The  chief-of-detachment  is  posted  two  yards  in  rear  of  the 
breech,  chassis,  or  trail,  or  on  the  left  of  the  pole,  two  yards 
from  and  opposite  its  end,  according  as  the  piece  is  dismounted, 
unlimbered,  or  limbered.  During  the  execution  of  ttie  manoeu- 
vres he  goes  wherever  his  presence  may  be  necessary ;  but,  in 
rendering  assistance,  will  generally  place  himself  opposite  the 
gunner,  between  Nos.  3  and  5. 

416.  The  implements  and  machines  required  for  the  various 
operations  depend  upon  the  kind  and  weight  of  the  piece  and 
the  nature  of  the  manoeuvre  to  be  performed .  For  each  exer- 
cise, those  specially  required  are  given. 

In  every  case  the  minimum  number  of  each  is  given.  When 
much  work  is  to  be  done,  due  allowance  must  be  made  for  wear 
and  tear,  which,  with  heavy  material,  is  very  considerable. 
Sound  discretion  should  be  exercised  not  to  allow  the  wearing 
to  go  beyond  the  limit  of  safety. 

Those  now  used  for  siege-pieces  are  such  as  can  be  found  in 
most  localities ;  the  rollers,  chocks,  and,  if  necessary,  the  hand- 
spikes being  readily  shaped  from  sections  of  trees. 

(199) 


200 


MECHANICAL   MANOEUVRES. 


The  following  table  contains  implements  used  for  siege-pieces : 

{Plate  18.) 


Implements. 

i 

• 

5 

• 
00 

J 

o 

2 

$ 
bo 

Remakks. 

Long  roller 

Inch. 

84 
42 
12 
8,6 

7 
7 

67 

360 

Inch. 

Inch. 

Lb.  Oz. 

12     0 
25      6 
12      0 

0  6 
2     4 

1  0 

48      0 

8      8 

2  4 

55      0 

)  Grooved  H  in.  deep  in 
/  the  middle. 
Wedge-shape. 
£  Section  a  triangle.  Tap 
$  rounded  M  ofan  inch. 
}  Ends  "beveled  on  oppo- 
S  site  sides. 

t  Sometimes  called  moa- 
>  koy-wrench. 
Made  of  round  iron  0.75 
^in.  in  diameter, -with  a 
'  stout  hook  at  each  end ; 
4  length  of  links,  5  ins* 

.     6 
7 

2.75 
6 
5 

12 

r'nd 

r'nd 
r'nd 
3.5 

3 

2 

2.25 
1.25 

Roller-chock 

't'race-ropo 

Slinfl>chain 

156 

The  machines  and  their  uses  will  be  described  with  the  ma- 
noDuvres  for  sea-coast  pieces. 

41 7.  In  every  case  the  wooden  handspike  is  required,  and  to 
avoid  repetition  the  following  general  directions  tor  its  use  are 
given.  Six  are  the  number  generally  used,  and  they  are  in 
charge  of  Nos.  1,  2,  3*  4,  5\  and  6. 

When  men  on  opposite  sides  of  a  piece  apply  themselves  to  a 
handspike,  the  handspike  used  is  that  of  one  of  the  even  num- 
bers ;  the  man  to  whom  it  belongs  is  at  the  smaller  end,  the 
corresponding  add  number  at  the  butt  end;  those  who  assist 
place  themselves  inside  of  these  two  numbers;  the  lowest  nun*- 
berg  nearest  the  ends- 

When  two  or  more  men  work  at  the  same  end  ot  a  handspike, 
the  mail  to  whom  it  belongs  is  at  the  end,  and  the  other  men  in 
the  ascending  order  of  their  numbers  from  him. 

When  several  handspikes  are  crossed  at  the  muzzle  m  order 
to  raise  or  lower  it,  they  am  applied  in  the  order  of  the  numtoei* 
of  the  men  to  whom  they  belong,  those  of  the  highest  numbers 
nearest  to  the  trunnions^ 

The  handspikes  used  in  the  mechanieai  mancBUvree  are  he veied 
on  Mia  skle,  as  these  will  enter  into  places  oe  under  feodie»  wftere 
s&twc  banttepikes  could  not  he  used. 

When  a  handspike  rests  on  a  fulcrum,  and  the  wetefcfc.oti>4N«» 


MJTttAL  DIKBCmOTO.  201 

«nd  is  to  be  raised  by  bearing  down  on  the  other,  ttie  weight 
should  never  vest  on  the  beveled  side,  as  the  handspike  would 
not  then  give  a  good  hold,  and  would  be  liable  to  split.  In  this 
•ease  the  beveled  side  should  be  down.  But  if  used  tor  lilting,  as 
when  two  handspikes  are  crossed  under  the  breech  or  chase  of  a 
£iro  to  heave  it  upward,  their  ends  resting  on  the  ground  or  plat- 
iorm,  the  beveled  side  should  be  up. 

Wlien  two  or  more  men  haul  together  on  a  rope,  the  lowest 
number  is  next  the  object  of  resistance,  and  the  remainder  next 
!him  in  ascending  order  of  their  numbers. 

4118.  At  the  completion  of  each  movement  of  a  manoeuvre, 
4he  men  retain  the  places  they  ore  ra  at  its  conclusion,  ready  to 
proceed  to  the  next  movement,  resuming  their  posts  only  at  the 
•command  To  your  posts,  which  is  given  by  the  instructor  at 
the  end  of  each  manoeuvre. 

419*  The  front,  when  a  piece  is  unlimbered  or  dismounted, 
is  the  direction  in  which  its  muzzle  points;  when  limbered,  it 
is  the  direction  in  which  the  pole  points.  In  the  execution  of 
the  following  manoeuvres,  when  a  piece  is  put  in  motion  upon 
rollers,  the  terms  back  and  forward  are  applied  to  ttie  direction 
•of  the  breech  and  muzzle  respectively. 

A  body  moving  upon  a  roller  gains  twice  the  distance  passed 
-over  by  the  roller. 

The  ground  should  be  level  and  firm  and  the  implements  in; 
good  order. 

Preparatory  to  ma/nteuvering,  the  implements  and  machines 
required  are  taken  to  the  place  of  exercise.  The  instructor  ex- 
plains to  the  detachment  their  names,  uses,  and  mode  of  appli- 
-cation.    He  then  commands : 

1.  Prepare  to  manoeuvre. 

42&.  The  mien  take  the  implements,  repair  to  their  posts, 
.and  place  them  upon  the  ground  in  their  rear ;  the  handspikes 
behind  Nos.  1,  2,  3,  4,  5,  and  6  perpendicularly  to  the  axis  of 
the  piece,  on  that  side  of  the  cannoneer  toward  the  muzzle,  the 
-small  ends  OB  a  "ne  with  their  toes ;  the  cl locks  equally  divided^ 
behind  and  near  Nos.  3  and  4 ;  the  long  rollers  near  and  behind 
Sfo*.  4,  and  the  short  rollers,  shifting-plank,  trace-rope,  sling- 
-chain,  and  hammer-wrench  in  rear  of  the  gunner. 

Whenever,  m  the  course  of  a  raaitosuvre,  aft  implement  is  not 
ia  immediate  use,  it  is  returned  by  the  person,  using  it  to  its  des- 
ignated place. 

4£UL  Tbe  instructor  gives  the  commands  and  has  a  gttftefcal 
aoperviskm  •*  the  manoeuvres.  He  sees  that  eaeh  man  perforwsi 
»Jm  .itoUaiiftMJgnttihto ;  ttu*  evexgrtttag  i*  m  a  pfcfcpec  state  oft 


202  MECHANICAL   MANCEUVBES. 

readiness  before  giving  the  command  of  execution ;  and  that  par- 
ticular care  is  taken  to  avoid  all  shocks  and  sudden  movements* 

422*  The  chief-of-detachment  attends  directly  to  the  execu- 
tioi\of  the  movements,  and  particularly  assists  and  directs  the 
gunner  in  all  his  duties. 

423*  The  gunner  gives  commands  when  specified;  places 
the  shifting-plank ;  attaches  and  takes  off  the  trace-rope ;  re- 
moves and  replaces  the  elevating  screw ;  places  and  removes- 
chocks  and  the  short  rollers;  superintends  the  righting  of  the* 
piece ;  directs  the  pole  of  the  limber,  &e. 

Nos.  1,  2,  3,  4,  5,  and  6  have  charge  of  the  handspikes ;  Nos. 
7  and  8  rig  and  work  the  windlass,  Nos.  1  and  2  holding  on  to- 
the  rope ;  Nos.  3  and  4  chock  and  un chock  the  wheels,  the  gunv 
and  the  long  rollers ;  take  off  and  replace  the  cap-squares,  and 
place  and  remove  the  long  rollers. 

Nos.  5  and  6,  with  their  handspikes,  steady  and  right  the 
piece,  haul  on  the  ropes,  &c.  Nos.  7,  8,  9,  and  10  assist  the 
others.  Nos.  7  and  8  generally  assist  Nos,  1  and  2,  or  3  and  4. 
Nos.  9  and  10  assist  Nos.  3  and  4,  or  5  and  6 ;  they  assist  in  plac- 
ing the  implements  preparatory  to  maneuvering;  haul  upon  the- 
ropes,  and  apply  themselves  by  hand  to  move  the  carriage. 

424.  Two  or  more  men,  lifting  or  hauling  together,  must 
wait  for  the  command  before  exerting  their  strength.  The  gun- 
ner sees  that  all  are  ready  before  giving  the  command  heave. 
Then  all  move  with  a  prompt  but  steady  effort,  and  apply  their 
power  increasingly  until  the  weight  responds  to  their  effort- 
The  gunner  will  repeat  the  command  heave  as  often  as  it  may 
be  necessary.  When  the  movement  has  been  sufficiently  ma<ler 
the  gunner  commands :  Ease  away.  Those  making  the  effort 
will  then  desist ;  but  in  doing  so  will  be  careful  to  avoid  all  sud- 
den shocks  or  strains. 

The  command  ease  away  will  be  omitted  in  the  text,  for  the 
reason  that  its  application  will,  in  most  cases,  depend  upon  cir- 
cumstances, to  be  judged  of  by  the  gunner. 

Every  operation  should  be  done  with  spirit  and  animation,, 
but  without  bustle  or  confusion.  Vigilance  should  be  constantly- 
exercised  to  have  the  piece  or  rollers  securely  chocked. 

425.  The  limber  of  a  siege-piece  makes  a  powerful  lever,, 
and  may  be  advantageously  used  in  many  cases.  The  pole  is- 
raised  and  the  pintle  engaged  in  a  sling  around  the  weight  to  be 
raised.  The  pole  is  hauled  down  by  a  trace-rope  attached  to- 
the  eye. 

426.  Parbuckling,  (Fig.  1,  Plate  19.)  A  rope  used  as  a  par- 
buckle is  the  best  method  of  rolling  a  gun.  To  do  this,  place- 
the  gun  on  skids,  and  attach  the  rope  by  a  bowline  to  one  of  the* 


GENERAL  DIRECTIONS.  203 

trunnions,  passing  it  under  and  around  up  over  the  gun,  and 
hauling  on  the  end. 

If  the  gun  is  to  be  rolled  up  a  slope,  two  ropes,  ol  size  suitable 
to  the  weight  of  the  gun,  are  used.  An  end  of  each  rope  is  made 
fast  to  some  fixed  object  at  the  upper  part  of  the  slope ;  the  other 
ends  are  carried  under  the  chase  and  body  respectively,  and  up 
over  the  gun ;  these  ends  are  hauled  upon  by  moans  of  a  cap- 
stan, or  by  attaching  to  them  a  fall  and  tackle.  The  muzzle  is 
slued  forward  by  pinching  with  bars,  or  by  means  of  a  rope 
and  tackle  attached  to  a  roller  or  skid  thrust  into  the  muzzle. 
The  piece  is  lowered  by  inverse  means. 

427.  To  cross-lift  a  piece  or  other  object  (Fig.  2,  Plate  19)* 
is  to  cross  handspikes  under  it  from  opposite  sides ;  the  butt  end 
of  the  handspike  is  on  the  ground,  and  the  power  is  applied  by 
lifting  at  the  other  end. 

428.  To  slue  the  trunnions  is  to  turn  the  piece  on  its  axis  so- 
as  to  bring  the  trunnions  into  any  required  position.    This  is 
done  by  first  placing  the  piece  on  skids  perpendicular  to  its  axis. 
A  fulcrum  is  placed  near  the  trunnion  to  be  raised  ;  upon  this  a 
handspike  or  other  lever  is  used,  the  piece  meanwhile  being- 
chocked  on  the  opposite  side.    Or  a  trunnion-loop  maybe  passea 
around  the  trunnion  to  be  raised,  and  a  handspike  or  lever  pass- 
ed through  it,  with  the  butt  end  resting  on  the  top  of  the  piece  ; 
the  power  is  applied  by  lifting  at  the  other  end,  the  piece  being 
chocked  as  before.    Or,  by  passing  the  bight  of  a  rope  once  or- 
twice  around  the  piece,  and  placing  the  butt  of  a  handspike  or 
lever  through  the  bight,  and  bearing  down  or  lifting  up,  using 
the  piece  as  a  fulcrum,  the  ends  of  the  rope  being  held  to  pre- 
vent them  from  slipping.    All  three  of  these  methods  may  be 
used  at  the  same  time. 

The  skids  should  be  well  greased  under  the  piece,  as  likewise 
should  be  the  chocks. 

When  the  piece  is  of  great  weight,  the  hydraulic-jack  or  ginf 
is  advantageously  used,  provided  the  axes  of  the  trunnions  are 
not  .vertical.  The  former  is  placed  under  and  the  latter  over  the 
trunnion  to  be  raised.  When  the  axes  of  the  trunnions  are  ver- 
tical, or  nearly  so,  a  rope  is  passed  around  the  upper  one  and 
hauled  upon  by  means  of  tackle. 

429.  To  pinch  a  gun  or  other  object  is  to  movo  it  by  small 
heaves  with  a  pinch-bar  or  handspike,  without  allowing  it  to 
turn  on  its  axis.  A  piece  is  pinched  one  end  at  a  time,  the  other 
being  ohocked.  The  bar  or  handspike  is  placed  as  a  lever,  with 
the  beveled  side  down,  and'  the  power  applied  at  the  other  end* 
by  bearing  down.  ■ 

.  4SO«  To  launch  a  piece  or  other  object  forward  or  backward 


Hb&4  MEOSANfCAL  iiA£<mvm&. 

Is  to  rti6v«  H  In  the  ejection  o*  its  afxia.  If  the  Weight  te  g*eh  as 
to  require  levers  or  handspikes,  they  are  placed,  usuaHy,  On  of*- 
^positc  sidels,  ant}  the  power  applied  by  bearing  down,  at  the  sa?me 
tiifre  carrying  the  free  end  of  the  lever  in  a  direction  contrary  Co 
•tfhat  in  which  the  object  is  to  be  moved. 

To  slue  a  pjece  or  other  object,  end  for  end,  is  to  turn  ft 
round,  not  allowing  it  to  revolve  on  its  longer  axis. 

To  cut  is  to  move  the  object  horizontally,  without  rolling,  by 
moving  each  end  alternately  in  the  required  direction. 

Manoeuvres  with  the  Siege  Gtjks. 

431*  The  implements  required  are  those  habitually  accom- 
panying each  piece,  viz. :  Six  handspikes,  two  trace-ropes,  six 
wheel-chocks,  one  hammer-wrench,  one  short  roller,  one  sling- 
chain,  and  four  roller-chocks, 

4&2.  The  following  manoeuvres  are  arranged  on  the  sup- 
position that  no  other  implements  are  available.  When  two  or 
more  pieces  are  together,  or  planks  or  skids  are  available,  as 
would  generally  be  the  case  in  the  field,  the  manoeuvres  may  be 
•often  simplified,  as  will  be  indicated. 

The  directions  laid  down  in  par.  417  and  following  will  be 
observed.  This  is  essential  for  the  prevention  of  confusion  and 
•accidents,  since  directions  to  particular  numbers  are  in.  moat 
cases  omitted. 

Ordinary  mwuzwres. 

1.  To  limber  and  to  mi  Umber. 

$.  To  move  the  carriage  when  limbered,  with  and  without  its 
rpiece,  by  hand  to  the  front  and  rear. 

3.  To  place  the  short  roller  under  the  chase  and  to  remove  it. 

4.  To  place  the  short  roller  under  the  body  of  the  gun  and  to 
remove  it. 

5;  To  shift  the  gun  from  its  traveling  bed  to  its  firing  bed. 

6*  To  shift  tthe  gun  from  its  firing  bed  to  its  traveling  bed. 

7.  To  side-lift  Che  carriage. 

All  the  other  manoeuvres  are  exceptional,  and  are  rarely  ro- 
xjuired  in  actual  service  with  the  guns  now  mounted  on  travell- 
ing carriages.  They  are\  therefore,  prescribed  for  exercieo  only 
4ft  sdch  an  extent  as  may  be  necessary  to  enable  office**  and  men- 
#o  become  familiar  with  the  operations. 

To  limber. 
(Fig.  3,  Plate  19.) 
4**w  TOftefe  tfeeue  guns  nm  aee*  for  ftetd  sfttfrttat  th«y  Ifcy 


uses  Quae.  206* 

be  limbered  to  the  rear,  front,  right,  or  left.    la  evttjr  flu**  Ibcr 

pieee  is  in  its  firing  bed. 
To  the  rear.    The  instructor  commands : 

l.  Limber  up. 

Nos.  3  and  4  chock  the  wheels  front  and  rear;  No.  2  inserts 
his  handspike  in  tlie  bore,  and  is  assisted  to  bear  down  by  No. 
1;  No.  6  crosses  his  handspike  under  the  stock,  as  near  the 
trail  as  practicable,  and  is  assisted  by  Nos.  3,  4,  5,  7,  and  8,  alt 
facing  in  the  direction  of  the  trail.  If  the  limber  is  not'  horsed* 
it  is  brouglit  up  by  the  chief -of-detachme ut,  guiltier,  and  Nos.  9 
and  10.  The  stock  is  raised  at  the  command  Heave  from  the 
guuner  until  the  pintle  can  be  caught  under  the  trail  au<l  the 
pole  used  as  a  lever  to  sustain  it.  The  handspike  is  then  shifted 
in  rear  of  the  lunette;  Nos.  0  and  10  take  hold  of  the  limber- 
wheels;  the  gunner  gives  the  neecssary  instructions  to  cause 
the  pintle  to  enter  the  lunette,  and  when  it  is  hi,  hooks  the 
lashing-chain. 

The  instructor  then  commands :  1.  To  your  posts  ;  at  which 
all  take  their  posts  as  explained  in  par.  415. 

To  th&  right*  or  to  the  left.  The  instructor  first  causes  the  trail 
to  be  moved  around  to  the  right  or  to  the  left,  so  as  to  bring  the 
axis  of  the  piece  perpendicular  to  its  former  position.  The  lim- 
ber is  moved  to  its  place  corresponding  to  the  new  position  of 
the  piece. 

In  moving  the  trail  around,  Nos.  1  and  3  at  the  right  wheel, 
and  Nos.  2  and  4  at  the  left,  apply  themselves  as  In  in  battery  of 
from  battery^  but  in  contrary  direction e.  as  the  case  may  require. 
Nob.  5  awl  8  both  em  bar  under  and  perpendicular  to  the  stock 
on  the  side  opposite  that  to  which  the  trail  is  to  be  moved.  The 
gunner  commands :  Heave,  and  repeats  it  as  often  as  may  be 
necessary.    The  piece  is  then  limbei«ed  up  as  before. 

To  the  frorU.  The  instructor  causes  the  trail  to  be  brought 
around  so  that  the  pieee  will  point  in  the  opposite  direction. 
This  may  be  done  either  to  the  right  or  left,  as  best  suited  to  the 
ground,  and  is  executed-  as  in  the  preceding  paragraph.  The 
limber  is  moved  to  its  place  corresponding  to  the  new  position 
of  the  piece,  and  passes  the  pieee  either  to  the  right  or  left,  ac- 
cording to  the  nature  of  the  ground.  The  piece  is  then  limbered 
tup  as  ha  the  preceding  cases. 

7o  urilimker. 
4K4«  T^  iejstr^eto^  eommanda ; 

1.  Unlimbeb. 
9he  gunner  unhooks  the  lashing-chain ;  N*s.  3  a«4  4  chock- 


2206  MECHANICAL   MAN<EUVRES. 

the  wheels  front  and  rear,  and  all  apply  themselves  as  in  limber- 
ing up.  At  the  command  Heave  from  the  gunner,  the  trail  is 
raised  to  disengage  it  from  the  pintle,  the  limber  is  moved  for- 
ward, and  the  trail  lowered  to  the  ground.  All  resume  their 
:posts  at  the  command  To  YOUR  POSTS. 

When  the  piece  is  unlimbered,  the  habitual  position  of  the 
timber  is  six  yards  in  rear  of  the  piece,  measured  from  its  axle 
to  the  trail,  the  pole  pointing  to  the  rear.  In  bringing  it  up  for 
limbering,  it  is  backed  to  its  place  at  the  trail.  If  the  carriage  is 
without  its  piece,  Nos.  1  and  2  embar  through  the  wheels  and 
under  the  rear  part  of  the  cheeks,  instead  of  as  prescribed  in 
par.  433. 

In  limbering  and  unlimbering  a  siege  howitzer,  Nos.  1  and  2 
both  insert  handspikes  in  the  bore. 

To  move  a  piece,  or  its  carriage,  to  the  front  or  rear. 

435.  The  instructor  commands : 

1.  Forward  (or  backward),  2.  March,  3.  Halt. 

The  piece  being  limbered,  Nos.  1  and  2  embar  obliquely  under 
■the  rear  of  the  wheels  of  the  carriage ;  Nos.  5  and  6,  in  like 
manner,  under  the  limber-wheels;  Nos.  3  and  4  through  the 
spokes  and  under  the  cheeks;  Nos.  7  and  8  apply  themselves  to 
the  limber-wheels  by  hand ;  Nos.  9  and  10  at  the  splinter-bar, 
and  the  gunner  and  chief-of-detachment  at  the  end  of  the  pole; 
all  facing  to  the  front.  The  gunner  commands:  Heave,  and 
repeats  it.  as  often  as  may  be  necessary. 

In  moving  to  the  rear,  Nos.  1  and  2  embar  through  the  spokes 
and  under  the  cheeks;  Nos.  3  and  4  under  the  front  of  the 
wheels  of  the  carriage ;  Nos.  5  and  6  under  the  front  of  the  lim- 
ber-wheels ;  Nos.  7,  8,  9,  10,  and  the  gunner  apply  themselves 
as  in  moving  to  the  front ;  all  facing  to  the  rear. 

The  carriage  being  limbered,  but  without  its  piece,  at  the  com- 
mand forward  the  numbers  apply  themselves  by  hand  as  fol- 
lows :  Nos.  1  and  2  at  the  head  of  the  cheeks ;  Nos.  3,  4,  5,  and 
6  at  the  wheels  of  the  carriage ;  Nos.  7  and  8  at  the  wheels  of 
the  limber;  Nos.  9  and  10,  and  the  gunner,  as  with  the  piece 
mounted.  At  the  command  march,  the  carriage  is  moved  for- 
ward. 

To  move  to  the  rear,  Nos.  1,  2,  3,  and  4  apply  themselves  by 
hand  to  the  wheels  of  the  carriage ;  Nos.  5  and  6  to  the  rear  end 
of  the  cheeks;  Nos.  7,  8,  9,  10,  and  the  gunner,  as  with  the 
piece  mounted.  At  the  command  march,  the  carriage  is  moved 
to  the  rear. 

In  the  foregoing  movements,  at  the  command  halt,  all  resume 
their  posts. 


SIEGE  GUNS.  207 

To  place  the  short  roller  under  the  chase. 

436.  The  piece  being  limbered  and  in  its  traveling  bed, 
the  instructor  commands : 

1.  Place  roller  under  the  chase. 

(Fig.  4,  Plate  19.)  At  this  command,  the  cap-squares  are 
removed  and  the  wheels  chocked  by  Nos.  3  and  4 ;  the  hand- 
spike of  No.  2  is  placed  in  the  bore ;  that  of  No.  6  is  crossed  un- 
der the  handspike  of  No.  2 ;  No.  1  assists  No.  2,  and  Nos.  3,  4, 
5.  7,  and  8  assist  No.  6.  The  gunner  stands  at  the  head  of  the 
light  cheek  with  the  roller,  and  when  all  is  in  readiness  gives 
the  command  Heave.  The  chase  being  raised  high  enough,  the 
roller  is  rolled  forward  on  the  stock  until  its  axis  is  within  six 
or  eight  inches  of  the  axis  of  the  trunnions,  and  cl locked  in  rear; 
the  piece  is  then  allowed  to  rest  on  it. 

Note. — The  roller  is  placed  under  the  chase  only  when  the 
piece  is  in  its  traveling  bed,  and  for  the  purpose  of  shifting  it. 

To  remove  the  short  roller  from  under  the  chase. 
437*  The  piece  being  limbered,  the  instructor  commands : 

1.  Remove  the  roller. 

Executed  as  in  the  foregoing  paragraph,  except  that  when  the 
-chase  is  raised  the  short  roller  is  rested  on  the  head  of  the  stock 
by  the  gunner,  to  enable  the  men  at  the  handspikes  to  take  a 
new  hold.  The  chase  being  raised  again,  the  roller  i3  with- 
drawn and  the  piece  lowered  into  its  bed. 

Either  of  these  operations  can  be  performed,  though  more 
time  is  required,  by  successive  purchases  with  the  handspikes 
over  the  heads  of  the  cheeks  and  under  the  chase. 

To  place  the  short  roller  under  the  body* 

438*  The  piece  being  either  limbered  or  unlimbered,  the  in- 
structor commands : 

1.  Place  roller  under  the  body. 

Nos.  3  and  4  chock  the  wheels  and  remove  the  cap-squares; 
No.  2  inserts  his  handspike  in  the  bore,  and  is  assisted  by  No.  1 
to  bear  down  ;  Nos.  5  and  6  embar  over  the  cheeks  ami  under 
the  gun  in  rear  of  the  trunnions,  and  raise  the  breech  at  the 
command  Heave  from  the  gunner  until  he  can  place  the  short 
roller  under  the  body  of  the  piece,  as  near  to  the  trunnions  as 
can  be  effected  readily.  The  gunner  chocks  the  roller  on  the 
side  toward  the  muzzle  when  the  piece  is  limbered,  and  iu  rear 


208  MECHA20CAL   MAINEUVRE8. 

when  unlkribered ;  removes  the  elevating  screw  and  places  it  in> 
rear  of  his  poet,  resting  it  upon  iu  handle*. 

Note. — Tlie  roller  is  placed  under  the.  body  of  the  piece  only 
when  it  is  in  its  firing  bed,  and  for  the  purpose  of  dismounting- 
it,  or  of  shifting  it  to  its  traveling  bed,  to  a  mortar- wagon,  or  to- 
another  carriage. 

To  remove  the  short  roller  from  under  the  body  of  the  piece. 

439.  The  piece  being  either  limbered  or  unlimbered,  the 
instructor  commands : 

1.  Remove  the  roller. 

The  gunner  replaces  the  elevating  screw,  and  the  roller  is  re- 
moved as  prescribed  in  the  preceding  paragraph. 

Note. — All  that  is  prescribed  iu  the  foregoiug  paragraphs  ap- 
plies likewise  to  the  siege  howitzer. 

To  shift  the  piece  from  its  traveling  to  its  firing  bed. 

(Fig.  5,  Plate  19.) 

440*  The  piece  being  Umbered,  the  instructor  cawses  a  roller 
to  be  placed  under  the  chase  as  explained  in  par.  436,  and  then 
commands : 

1.  Shift  the  piece. 

Nos.  3  and  4  remove  the  cap-sqnares ;  No.  2  inserts  his  hand- 
spike in  the  bore,  and  is  assisted  by  No.  1 ;  No.  6  crosses  his- 
handspike  over  that  of  No.  2,  and  is  assisted  by  Nos.  3,  4,  and  5. 
The  gunner  attaches  the  trace-rope  at  its  middle  by  a  double 
hitcii  to  the  knob  of  the  cascable,  and  passes  the  ends  over  the 
limber  to  Nos.  7,  8,  9,  and  10,  who  take  a  turn  with  each  part 
around  the  maneuvering  bolts.  At  the  command  Heave  from 
the  gunner,  the  muzzle  is  borne  down  and  the  piece  allowed  to- 
run  slowly  on  the  roller  until  the  trunnious  are  over  their  firing 
beds,  when  they  are  borne  down  into  place  and  the  short  roller 
removed  from  the  roar. 

Before  executing  this  or  any  similar  manoeuvre,  the  manoeu- 
vering  bolts  should  be  set  tight  to  the  stock  with  the  wrench,  to 
prevent  accidents  from  turning.  The  precaution  should  be  taken* 
also,  of  putting  a  chock  near  the  head  of  the  stock  to  stop  the 
roller,  should  the  men  at  the  trace-rope  fail  to  control  the  piece 
after  the  trunnions  have  been  lifted  over  the  chin  bolts. 

The  gunner  must  observe  that  the  lashing-chain  is  hooted. 

To  shift  the  piece  from  its  firing  to  Us  traveling  tied* 
441.  Th*  pieoe  btlng  timbered},  the  inatvuetor  qrann  the 


SIEGE   GUNS.  208 

roller  to  be  placed  under  the  body  of  the  piece  as  explained  in 
par.  438,  and  then  commands : 

1.  Shift  the  piece. 

At  this  command,  No.  2  inserts  his  handspike  in  the  bore;  the 
handspike  of  No.  4  is  crossed  under  that  of  No.  2,  and  manned 
by  Nos.  1,  2,  3,  and  4;  the  gunner  attaches  the  trace-rope  at  its 
middle  to  the  knob  of  the  cascable  by  a  double  hitch,  and  passes 
its  ends  over  the  limber  to  Nos.  5,  0,  7,  8,  9,  and  10.  At  the 
command  Heave  by  the  gunner,  the  piece  is  pushed  and  hauled 
until  the  trunnions  are  over  their  traveling  beds  when  the 
breech  is  allowed  to  rest  on  the  bolster.  The  roller  is  removed 
from  the  front  by  raising  the  muzzle  as  described  in  par.  437. 

442.  Note. — In  any  of  the  preceding  manoeuvres  with  the 
8-incli  howitzer,  when  the  handspike  of  No.  2  is  inserted  in  the 
muzzle  it  should  be  chocked  about  18  inches  in  the  bore,  and 
again  at  the  muzzle.  When  the  howitzer  is  transported  on  its 
traveling  bed,  a  temporary  bolster  should  be  constructed  to  sup- 
port- the  breech.  The  short  roller,  resting  on  a  piece  of  plank 
two  or  three  inches  thick  and  supporting  the  knob  of  the  casca- 
ble, will  answer  for  this  purpose. 

To  side-lift  a  carriage. 

443.  For  the  purpose  of  moving  a  carriage  a  short  distance  tc 
the  right  or  left,  it  being  unlimbered,  the  instructor  commands  . 

1.  Side-lift  to  the  right  (or  left). 

To  the  right.  Nos.  2  and  4  cmbar  under  and  perpendicular 
to  the  left  wheel,  from  the  outside;  Nos.  1  and  3  under  the 
right  wheel,  from  the  inside,  and  No.  6  under  and  perpendicu- 
lar to  the  trail.  The  gunner  commands:  Heave,  and  the  car- 
riage is  lifted,  short  distances  at  a  time,  to  the  right. 

To  the  left.  Executed  in  the  same  manner,  but  by  inverse 
means. 

Remarks. 

444.  The  short  roller  is  carried  as  explained  in  par.  256. 
When  the  piece  is  on  its  traveling  bed,  the  elevating  screw  is 

run  in  on  the  lower  side  of  the  stock,  and  held  in  its  place  by  a 
lashing-strap. 

The  sponge  and  rammer  are  lashed  upon  the  piece,  their 
heads  projecting  beyond  the  base  of  the  breech.  A  convenient 
way  of  transporting  them  is  by  two  iron  collars,  containing 
hooks,  buckled  upon  the  breed i  and  chase. 

The  handspikes  are  carried  as  explained  in  par.  256. 

14 


210  MECHANICAL    MANOEUVRES. 


Two  trace-ropes  should  accompany  each  piece  of  siege  artil- 
lery. They  are  useful  not  only  in  shifting  the  piece,  but  in  lash- 
ing and  in  extricating  the  carriage  or  mortar-wagon  from  diffi- 
culties. 

The  sling-chain  is  carried  wound  around  the  stock.  It  may 
be  used  for  a  lock-chain,  the  one  provided  with  a  shoe  being  dis- 
pensed with. 

The  sh  if  ting-plank  is  carried  on  the  stock,  between  the  cheeks. 
A  hole  is  bored  in  it,  through  which  a  rope  passes,  securing  it  to 
the  stock. 


ii 


The  chocks  and  hammer-wrench  are  best  carried  in  a  bag 
slung  to  some  part  of  the  carriage. 

445.  To  prepare  a  piece  for  traveling,  the  instructor  causes 
the  implements  to  be  placed  as  above  indicated.  To  do  this, 
after  shifting  the  piece  to  its  traveling  bed  he  commands : 

1.  Put  on  the  implements. 

The  gunner  places  the  vent-cover,  short  roller,  elevating  screw, 
and  water-bucket ;  if  it  is  necessary  to  lash  the  piece  to  its  bed, 
he  is  assisted  by  Nos.  1,  2,  3,  4,  5,  and  6.  No.  2  secures  the  tom- 
pion  in  the  muzzle ;  Nos.  1  and  2  fasten  on  the  sponge  and  ram- 
mer, and,  assisted  by  Nos.  3  and  4,  put  on  the  handspikes.  The 
piece  is  lashed  as  explained  in  par.  256. 

To  prepare  the  piece  for  action,  the  instructor,  before  shifting 
it  to  its  tiring  bed,  commands : 

1.  Kemove  the  implements. 

The  same  numbers  that  put  on  the  implements  remove  them. 

446.  The  object  of  carrying  the  piece  in  the  traveling  bed  is 
to  equalize  the  load,  by  throwing  more  of  the  weight  upon  the 
limber,  and  thus  relieving  the  rear  wheels.  For  short  distances, 
over  smooth  roads,  the  piece  may,  however,  be  carried  in  its 
firing  bed. 

Other  Manceuvres  which  may  be  required  in  Service. 

To  mount  the  siege  gun  on  its  carriage. 

44V.  The  piece  is  lying  on  the  ground,  vent  uppermost ;  the 
carriage  unlimbered;  the  elevating  screw,  bolster,  and  cap- 
squares  removed ;  the  trail  about  two  yards  from  the  muzzle ; 
the  stock  squarely  in  prolongation  with  the  gun.  The  instruct- 
or commands : 

1.  Raise  the  chase. 

(Fig.  1,  Plate  20.)     The  gunner  extends  the  sling-chain  on 


SIEGE   GUNS.  211 

the  ground  perpendicularly'  to  the  axis  of  the  piece,  with  its 
middle  under  the  neck  of  the  cascable ;  No.  2  inserts  his  hand- 
spike in  the  bore,  and  is  assisted  to  lift  by  No.  1 ;  Nos.  3  and  4, 
with  their  handspikes,  cross-lift  under  that  of  No.  2;  Nos.  5 
and  6  stand  ready  with  their  handspikes  to  thrust  them  under 
the  piece  as  soon  as  it  is  raised.  At  the  command  Heave  from 
the  gunner,  it  is  raised  by  Nos.  1,  2,  3.  and  4,  and  the  gunner 
places  the  roller  under  the  muzzle;  Nos.  5  and  6  thrust  their 
handspike?  under  the  chase,  in  the  position  for  cross-lifting; 
Nos.  3  and  4  take  fresh  holds  under  the  chase;  the  gunner  com- 
mands: Heave,  and  the  piece  is  raised  until  the  gunner  can 
place  the  roller  under  it  a  short  distance  in  rear  of  the  trun- 
nions. The  carriage  is  then  run  back,  as  from  battery  (par. 
237),  until  the  muzzle  catches  on  a  roller  placed  on  the  stock. 
(Fig.  2,  Plate  20.)  By  cross-lifting  the  piece  as  before,  the 
roller  on  the  ground  is  removed  and  the  piece  allowed  to  rest 
on  the  roller  on  the  stock. 

The  stock  serves  as  an  inclined  plane,  up  which  the  piece 
moves  on  the  roller.  The  carriage  Is  now  worked  back,  as  from 
battery,  as  far  as  the  trail,  under  the  gun,  will  allow  it  to  go. 

The  instructor  commands : 

1.  Sling  the  piece. 

Nos.  7,  8,  9,  and  10  run  back  the  limber  until  the  pintle  is 
slightly  in  rear  of  the  knob  of  the  cascable,  and  the  wheels  arc 
chocked  front  and  rear.  The  wheels  of  the  gun  carriage  are 
chocked  in  front. 

The  gunner  attaches  one  end  of  a  trace-rope  to  the  eye  of  the 
limber  pole,  and  Nos.  7,  8,  9,  and  10  stand  ready  and  raise  it  at 
the  command  heave  from  the  gunner.    (Fig.  2,  Plate  20.) 

No.  10  holds  on  to  the  rope  to  prevent  the  pole  from  going 
over  too  far.  The  pole  having  been  raised,  the  gunner  dra\V3 
the  sling-chain  up  tightly  over  the  pintle  and  hooks  it.  Nos.  7, 
8,  and  9  go  to  the  assistance  of  No.  10  at  the  rope,  and,  at  the 
command  Heave  from  the  gunner,  draw  the  pole  down  to  the 
ground.  The  pole  is  held  down  and  the  carriage  is  run  back,  as 
from  battery,  until  the  trunnions  nearly  or  quite  touch  the  trav- 
eling trunnion  bolts.  The  roller  is  chocked  in  rear,  and  the 
piece  secured  in  this  position  by  laying  the  middle  of  a  trace- 
rope  over  it  just  in  rear  of  the  trunnions,  carrying  the  ends  to 
the  front  under  them  and  making  fast  to  the  axle-tree. 

The  sling-chain  is  then  unhooked  and  cast  off  from  the  pintle. 

The  instructor  commands : 

1.  Sling  the  stock. 
The  gunner  doubles  the  sling-chain  at  the  middle  and,  passing 


212  MECHANICAL    MANCEUVRES. 

the  bight  under  the  stock  from  left  to  right,  places  it  over  the 
right  manoeuvering  bolt.  Nos.  7,  8,  9,  and  10  back  the  limber 
so  that  the  end  of  the  fork  will  have  full  play  on  the  left  of  the 
stock  when  the  pole  is  raised ;  chock  the  limber-wheels,  front 
and  rear;  raise  the  pole  as  prescribed  in  the  preceding  para- 
graph. 

The  pintle  should  then  be  over  and  slightly  to  the  rear  of  the 
left  manoeuvering  bolt.  Bring  up  both  ends  of  the  sling-chain 
behind  the  lefc  manoeuvering  bolt,  pass  one  end  around  the  pin- 
tle, taking  in  all  the  slack,  and  fasten  the  hook  in  a  convenient 
link  of  the  other  end.  The  wheels  of  the  limber  are  now  un- 
choeked,  and,  at  the  command  Heave  from  the  gunner,  the 
pole  is  hauled  down  to  the  ground  as  in  the  preceding  para- 
graph. The  stock  should  now  be  nearly  horizontal;  if  it  is  not, 
support  the  trail  with  a  roller,  or  any  other  convenient  method, 
and,  shortening  the  sling-chain,  take  a  new  lift. 

The  instructor  commands  i 

1.  Shift  the  roller. 

(Fig.  3,  Plate  20.)  No.  2  places  his  handspike  in  the  bore, 
and  is  assisted  by  No.  1 ;  No.  4  crosses  his  under  that  of  No.  2, 
and  is  assisted  by  Nos.  3,  5,  6,  7,  and  8 ;  Nos.  9  and  10  hold 
down  the  pole.  At  the  command  Heave  from  the  gunner,  the 
gun  is  raised  and  the  roller  is  shifted  to  just  in  front  of  the 
trunnions. 

The  instructor  commands : 

1.  Shift  the  piece. 

(Fig.  4,  Plate  20.)  The  trace-rope  is  cast  off  from  the  piece ; 
the  gunner  attaches  it  at  the  middle  to  the  knob  of  the  cascable, 
and  passes  the  ends  over  the  axle  of  the  carriage  to  Nos.  3,  4,  5, 
and  6;  No.  2,  with  his  handspike  in  the  bore,  is  assisted  to  lift 
and  bear  down  by  No.  1.  At  the  command  Heave  from  the 
gunner,  the  piece  is  hauled  forward  until  the  trunnions  clear 
the  chin  bolts,  when  the  muzzle  will  at  once  be  borne  down, 
causing  the  trunnions  to  drop  into  their  firing  beds.  As  the 
muzzle  approaches  the  ground  the  handspike  must  be  shoved 
into  the  bore.  The  pole  is  raised  and  the  trail  allowed  to  rest 
on  the  ground,  the  sling-chain  disengaged,  and  the  roller  re- 
moved by  the  rear. 

To  dismount  the  siege  gun  from  its  carriage, 

(Fig.  5,  Plate  19.) 

448*  The  piece  being  limbered  and  the  wheels  chocked,  the 
Instructor  causes  a  roller  to  be  placed  under  the  body  of  the  piece 


SIEGE   GUNS.  213 

as  explained  in  par.  438.     The  roller  is  chocked  on  the  side  to- 
wards the  trail.    The  instructor  then  commands  : 

1.  Dismount  the  piece. 

{Fig.  5,  Plate  20.)  The  gunner  attaches  the  trace-rope  by 
its  middle  with  a  double  hitch  to  the  knob  of  the  cascable,  and 
passes  the  ends  to  Nos.  9  and  10,  who  take  two  turns  with  them 
around  the  manoeuvering  bolts  and,  hauling  taut,  stand  ready  to 
ease  off  when  directed  ;  Nos.  3  and  4  remove  the  cap-squares  ; 
No.  2  places  his  handspike  in  the  bore,  and  is  assisted  to  lift  by 
No.  1 ;  No.  4  crosses  his  handspike  under  that  of  No.  2,  and  is 
Assisted  to  lift  by  Nos.  3,  5,  6,  7,  and  8. 

At  the  command  Heave  from  the  gunner,  the  muzzle  is  raised ; 
the  rope  is  carefully  slacked  off;  the  trunnions  are  eased  over 
the  eye-bolts  and  allowed  to  rest  on  the  cheeks;  Nos.  9  and  10 
ease  off  the  rope,  and  allow  the  piece  to  run  forward  until  the 
trunnions  clear  the  cheeks,  when  the  muzzle  is  depressed  and 
allowed  to  rest  on  the  ground,  No.  2  pushing  his  handspike  up 
the  bore  for  this  purpose.  The  rope  is  cast  off  and  the  wheels 
unchoeked. 

The  carriage  is  then  run  forward  as  explained  in  par.  435,  and 
the  piece  allowed  to  drop  to  the  ground. 

In  performing  this  manoeuvre  with  a  single  roller,  the  breech 
is  sometimes  jammed  between  the  cheeks,  or  the  head  of  the 
stock  bruised  by  the  knob  of  the  cascable.  Both  of  these  diffi- 
culties are  obviated  by  using  two  short  rollers,  the  second  one 
being  rolled  down  the  stock  against  the  first  before  running  the 
carriage  out. 

If  the  piece  is  dismounted  in  this  manner  on  hard,  stony  soil, 
some  material,  as  hay,  brush,  &c,  should  be  placed  to  receive  it 
hi  its  fall. 

Note. — In  the  above  or  other  similar  manoeuvres,  should  no 
limber  be  available,  the  stock  may  be  temporarily  supported  in 
a  horizontal  position  by  any  means  most  convenient. 

To  shift  the  siege  gun  from  one  carriage  to  another. 

(Fig.  1,  Plate  21.) 

449*  The  piece  is  unlimbered ;  the  spare  carriage,  limbered, 
with  cap-squares  and  elevating  screw  removed,  is  placed  with  its 
pole  pointing  in  the  same  direction  as  the  trail  of  the  piece,  and 
two  or  three  yards  distant  therefrom. 

The  roller  is  placed  under  the  body  of  the  piece  as  in  par. 
438. 

The  instructor  commands:  1.  Raise  the  chase.    At  this 


214  MECHANICAL   MANOEUVRES. 

command,  No.  2  inserts  his  handspike  in  the  bore,  and  is  assisted 
by  No.  1 ;  No.  4  crosses  his  under  that  of  No.  2,  and  is  assisted 
by  Nos.  3, 5,  and  6;  the  gunner  gives  tiie  command  Heave,  and 
the  chase  is  raised  until  a  wheel-chock,  base  up,  or  the  butt  end 
of  a  handspike,  can  be  placed  by  Nos.  7  and  8  under  each  trun- 
nion. 

The  instructor  causes  the  trace-rope  to  be  attached  by  its  mid- 
dle, with  a  double  hitch,  to  the  knob  of  the  cascable  ;  the  spare 
carriage  is  then  backed  accurately,  wheel  to  wheel,  against  the 
carriage  of  the  piece,  and  the  wheels  chocked  ;  the  ends  of  the 
trace-ropes  are  passed  over  the  spare  carriage  to  Nos.  9  and  10. 
The  gunner  then  places  the  shifting-plank,  with  one  end  on  the 
head  of  the  stock  of  the  spare  carriage,  and  the  other  end,  beveled 
side  down,  on  the  stock  under  the  gun.  The  gunner  commands  : 
Bear  down  the  muzzle,  which  is  done  by  Nos.  1,  2,  3,  and  4, 
while  the  gunner  places  the  roller  on  the  plank  about  eight  inches 
in  rear  of  the  trunnions.  The  instructor  commands:  1.  Shift 
the  piece.  Nos.  5,  6,  7,  and  8  go  to  the  ropes  to  haul  with 
Nos.  9  and  10.  Those  at  the  muzzle  prepare  to  lift.  The  gun- 
ner commands  :  Heave,  and  the  piece  is  moved  back  until  the 
trunnions  are  over  the  beds  on  the  spare  carriage  ;  another  roll- 
er is  then  placed  on  the  stock  of  the  carriage,  under  the  bod3r  of 
the  gun. 

The  instructor  commands :  1.  Remove  the  plank.  Nos.  1 
and  2  embar  with  their  handspikes  over  the  cheeks  of  the  now 
free  carriage  and  under  the  chase,  and  are  assisted  to  bear  down 
by  Nos.  3  and  4.  The  gunner  commands:  Heave;  the  chase 
is  raised ;  the  plank  and  roller  are  removed ;  the  roller  is  placed 
on  the  head  of  the  stock  of  the  free  carriage,  and  the  muzzle 
rested  on  it. 

The  instructor  commands :  Run  out  the  carriage.  Ex- 
ecuted as  in  in  battery.  (Par.  242.)  The  piece  drops  into  the  truu- 
nion  beds,  after  which  the  roller  under  the  body  is  removed  by 
the  rear  as  in  par.  439.  The  cap-squares  and  elevating  screw 
are  replaced. 

To  mount  the  siege  gun  on  the  mortar-wagon, 
(Fig.  2,  Plate  21.) 

4L50*  The  gun  is  lying  on  the  ground;  the  mortar-wagou, 
unlimbered,  its  stakes  and  bolster  removed,  is  in  the  prolon- 
gation of  the  piece;  its  trail  on  the  ground  about  two  yards  from 
the  breech. 

The  instructor  commands : 


SIEGE   GUNS.  215 

1.  Raise  the  chase. 

Executed  as  in  par.  447,  except  that  the  sling-chain  is  not 
placed  under  the  neck  of  the  cascablc.  After  the  roller  is  placed 
under  the  trunnions,  tip  the  muzzle  down,  and  back  the  mortar- 
wagon  until  the  breech  catches  on  another  roller  placed  on  the 
stock ;  the  wheels  are  then  chocked. 

Note. — A  limber  may  be  used  to  sling  the  piece  until  the 
breech  rests  on  the  roller  placed  on  the  stock,  and  subsequently 
to  sling  the  muzzle  clear  of  the  ground  to  prevent  its  dragging. 

The  instructor  commands : 

1.  Rig  the  windlass. 

{Fig.  3,  Plate  21.)  The  gunner  lays  the  middle  of  the  trace- 
rope  over  the  piece  in  rear  of  the  trunnions ;  brings  the  ends 
under  and  around  over  the  trunnions ;  takes  two  turns  with  each 
end  around  the  middle  of  the  windlass,  the  standing  parts  to- 
ward the  ends ;  Nos.  1  and  2  take  hold  of  the  ends  of  the  rope 
to  hold  on  and  take  up  the  slack;  Nos.  7  and  8  insert  the  hand- 
spikes into  the  ratchet-sockets,  and  are  assisted  by  Nos.  9  and 
10;  Nos.  3,  4,  5,  and  6,  with  their  handspikes,  steady  the  piece. 
At  the  command  Heave  from  the  gunner,  the  piece  is  drawn 
up  the  stock.  When  the  roller  under  the  chase  becomes  free,  it 
is  placed  under  the  breech. 

Draw  the  piece  back  on  the  wagon  until  the  trunnions  are 
about  eighteen  inches  in  front  of  the  axle-tree;  the  gunner  re- 
places the  bolster,  and  Nos.  3  and  4  chock  the  rollers  front  and 
rear,  and  likewise  the  wheels  of  the  wagon. 

Note. — H  the  wheels  are  unchocked,  the  stock  will  work  itself 
under  the  piece  and  considerably  relieve  the  strain  on  the  ropes. 

The  instructor  commands : 

1.  Limber  up. 

Executed  as  in  par.  433,  except  that  Nos.  1  and  2  hold  on  to 
the  ropes  and  prevent  them  from  slipping  on  the  windlass. 
The  instructor  commands : 

1.  Stow  the  piece. 

(Fig.  4,  Plate  21.)  Nos.  1  and  2  cast  off  the  rope  from  the 
windlass  and  carry  the  ends  to  the  front.  The  gunner  changes 
the  middle  of  it  so  that  it  will  cross  the  gun  in  front  of  the  trun- 
nions. Nos.  7,  8,  9,  and  10  assist  Nos.  1  and  2  to  haul  upon  the 
ropes;  Nos.  3,  4,  5,  and  0,  with  their  handspikes,  steady  the 
piece;  the  rollers  are  unchocked.  At  the  command  IIeave 
from  the  gunner,  the  piece  is  hauled  forward  until  the  breech  is 


216  MECHANICAL    MANOEUVRES. 

over  its  seat  in  the  wagon ;  the  front  roller  is  chocked  and  the 
muzzle  borne  down  until  the  rear  roller  can  be  removed;  the 
breech  is  then  allowed  to  rest  in  its  seat.  The  front  roller  is 
removed  by  raising  the  chase  as  explained  in  par.  436,  and  the 
chase  is  allowed  to  rest  on  the  bolster.  The  stakes  of  the  wagon 
are  replaced  in  their  sockets. 

To  dismount  the  siege  gun  from  the  mortar-wagon. 

451.  The  wagon  being  limbered  and  the  stakes  removed,  the 
instructor  commands : 

1.  Place  the  roller  under  the  chase. 

Executed  in  a  manner  similar  to  that  explained  in  par.  436. 
The  roller  is  chocked  front  and  rear.  The  numbers  who  lifted 
at  the  muzzle  now  bear  it  down,  and  another  roller  is  placed 
under  the  body  of  the  piece,  about  eighteen  inches  in  rear  of  the 
trunnions.  The  bolster  is  removed,  and  the  instructor  com- 
mands: Rig  the  windlass.  Executed  as  in  par.  450.  At 
the  command  Heave  from  the  gunner,  the  piece  is  hauled  back 
until  the  trunnions  are  about  eighteen  inches  in  front  of  the 
axle-tree;  both  rollers  are  chocked  front  and  rear. 

The  instructor  commands : 

1.  Unlimber. 

Executed  as  in  par.  434,  except  that  Nos.  1  and  2  hold  on  to 
the  ends  of  the  ropes  and  prevent  them  from  slipping  on  the 
windlass. 

Note. — In  this  operation  care  must  be  taken  that  the  gun  is 
not  too  far  to  the  rear,  thus  endangering  the  tipping  over  back- 
wards of  the  wagon. 

The  instructor  commands : 

1.  Lower  the  piece. 

Nos.  1  and  2  ease  off  the  ropes  and  allow  the  piece  to  descend 
on  the  stock.  As  the  rollers  become  disengaged  in  rear  they  are 
placed  under  the  piece  in  front.  When  the  muzzle  strikes  the 
ground,  the  wheels  may  be  unchocked  and  the  carriage  moved 
to  the  rear,  thus  permitting  the  piece  to  descend  to  the  ground. 

To'  shift  the  siege  gun  from  its  carriage  to  the  mortar-wagon. 

452.  The  piece  and  mortar-wagon  are  both  limbered ;  the 
latter  is  placed  in  rear  of  the  former,  but  faced  in  the  oppo- 
site direction  ;  the  windlass  two  or  three  yards  from  the  muzzle 
of  the  piece.  The  instructor  causes  the  roller  to  be  placed  under 
the  bod\r  of  the  piece  as  explained  in  par.  438. 


SIEGE   GUNS.  217 

He  then  commands : 

1.  Haul,  back  the  piece. 

The  gunner  attaches  the  trace-rope,  by  its  middle,  to  the  knob 
of  the  cascable,  and  passes  the  ends  to  Nos.  a,  6,  7,  8.  9,  and  10. 
Nos.  1,  2, 3,  and  4  apply  themselves  as  in  par.  441.  The  gunner 
commands  Heave,  and  the  piece  is  moved  back  until  the  trun- 
nions rest  on  the  cheeks  just  behind  the  chin  bolts. 

The  roller  is  removed  by  the  rear  as  explained  in  par.  439, 
and  the  wagon  is  backed  up  to  the  carriage,  wheel  to  wneel,  and 
chocked. 

The  instructor  commands : 

1.  Shift  the  piece. 

The  gunner  places  the  shifting-plank  from  the  head  of  the 
stock  to  the  mortar- wagon,  and  places  the  roller  on  it  under  the 
chase,  working  it  back  as  far  toward  the  trunnions  as  practica- 
ble, the  piece  being  raised  by  successive  purchases  over  the 
cheeks  and  under  the  chase.  Remove  the  bolster  (which  is  use- 
ful as  a  fulcrum);  a  turn  is  taken  around  each  manoeuvering 
bolt  with  the  trace-rope,  which  is  held  by  Nos.  5,  6,  7,  8,  9,  and 
10.  At  the  command  Heave  from  the  gunner,  Nos.  1,  2,  3, 
and  4  bear  down  on  the  muzzle  and  permit  the  piece  to  run 
forward  onto  the  wagon,  where  the  chase  is  received  on  a  roller. 

The  roller  is  removed  and  the  piece  stowed  as  explained  in 
par.  450. 

Note. — The  gun  may  be  shifted  to  the  mortar- wagon,  (the 
piece  being  limbered,)  without  a  shifting-plank,  by  the  use  of  a 
second  roller  to  receive  the  body  of  the  gun  on  the  mortar-wagon. 
The  preliminaries  are  the  same  as  before;  the  trunnions  being 
held  on  the  cheeks,  the  roller  is  placed  well  up,  just  in  rear 
of  them;  the  trace-rope  taut  and  around  the  manoeuvering 
bolts ;  the  muzzle  is  raised,  the  wagon  backed  wheel  to  wheel, 
and  the  chase  rested  on  a  roller  which  is  placed  on  the  rear 
cross-bar  plate,  and  receives  the  body  of  the  gun  as  the  first 
roller  runs  off  the  head  of  the  stock. 

To  shift  the  siege  gun  from  the  mortar-wagon  to  its  carriage. 

453*  This  operation  is  executed  by  means  the  inverse  of 
those  explained  in  the  preceding  paragraphs. 

When  the  trunnions  are  over  their  beds,  the  shifting-plank 
and  roller  are  extricated  by  cross-lifts  under  the  chase,  and 
the  chase  allowed  to  rest  on  a  roller  so  placed  that  when  the 
mortar-wa^on  is  run  to  the  front  the  muzzle  will  clear  the  wagon 
as  it  drops  from  the  roller;  thus  permitting  the  trunnions  to  fall 


218  MECHANICAL    MANOEUVRES. 

into  their  beds.     Meanwhile  the  piece  is  held  fast  by  taking  one 
or  two  turns  of  the  trace-rope  round  the  maneuvering  bolts. 

To  stand  the  siege  howitzer  on  its  muzzle. 

454.  The  piece  is  lying  on  the  ground.  The  instructor 
commands : 

1.  Kaise  the  ohase. 

Nos.  1  and  2  insert  their  handspikes  in  the  muzzle  and  chock 
them  on  top;  No.  4  crosses  his  handspike  under  those  in  the 
muzzle,  and  is  assisted  to  lift  by  Nos.  3,  5,  and  6;  Nos.  7  and  8 
assist  Nos.  1  and  2.  At  the  command  Heave  from  the  gunner, 
the  piece  is  raised  and  a  shifting-plank  run  under  it  parallel  to 
the  axis ;  a  short  roller  is  placed  on  the  plank  under  the  trun- 
nions perpendicular  to  the  axis  of  the  piece.  The  roller  is  chocked 
front  and  rear. 

The  instructor  commands : 

1.  Kaise  the  breech. 

(Fig.  1,  Plate  22.)  Nos.  1  and  2  withdraw  their  handspikes; 
No.  2  crosses  his  over  the  muzzle,  and  is  assisted  to  bear  down 
by  Nos.  1,  3,  and  4 ;  No.  6  crosses  his  under  the  neck  of  the 
cascable,  and  is  assisted  to  lift  by  Nos.  5,  7,  8,  9,  and  10.  At 
the  command  Heave  by  the  gunner,  the  breech  is  raised  until 
the  muzzle  rests  upon  the  ground.  The  men  at  the  muzzle 
hold  it  in  this  position  while  the  gunner  attaches  the  middle  of 
a  trace-rope  by  two  half  hitches  to  the  middle  of  a  handspike, 
and  places  it  under  the  neck  of  the  cascable ;  the  ends  of  the  rope 
are  brought  up,  one  on  each  side  of  the  cascable,  and  crossed  on 
the  breech  ;  Nos.  7, 8, 9,  10,  the  gunner,  and  chief-of -detachment 
man  the  ropes  and  hold  taut,  while  Nos.  1,  2,  3,  4,  5.  and  6  man 
the  handspike. 

The  gunner  then  commands :  Heave  ;  and  all  lift  and  haul 
until  the  piece  stands  on  the  muzzle. 

To  dismount  the  siege  howitzer. 

(Fig.  2,  Plate  22.) 

455*  The  piece  being  unlimbered,  the  instructor  commands: 

1.  Dismount  the  piece. 

The  gunner  attaches  one  end  of  a  trace-rope  to  one  of  the 
manoeuvering  bolts ;  Nos.  3  and  4  chock  the  wheels  front  and 
rear ;  Nos.  1  and  2  lay  their  handspikes  on  the  ground  parallel 
to  the  axis  of  the  piece,  in  such  position  that  the  muzzle,  when 
it  comes  over,  will  rest  squarely  on  their  largest  part,— or  if  a 


SIEGE   HOWITZERS.  219 

sliif ting-plank  is  used,  they  place  it  instead  of  the  handspikes; 
No.  10  holds  on  to  the  rope ;  all  the  other  numbers  lift  by  hand 
at  the  stock;  Nos.  1  and  2  being  nearest  the  axle-tree,  and  the 
other  numbers  arranged  in  their  order  towards  the  trail.  At  the 
command  Heave  from  the  gunner,  the  trail  is  raised  until  a 
handspike,  butt  end  on  the  ground,  can  be  placed  under  it  by 
No.  9,  who,  following  up  the  movement,  supports  the  stock.  The 
gunner  repeats  the  command  Heave  until  the  muzzle  rests 
squarely  on  the  handspikes  or  shifting-plank ;  the  numbers  at 
the  stock  quit  it  as  the  weight  passes  to  the  front,  and  go  to  the 
assistance  of  No.  10  at  the  rope. 

As  soon  as  the  piece  rests  on  the  muzzle,  Nos.  3  and  4  remove 
the  cap-squares. 

The  gunner  cautions  those  at  the  rope  to  keep  a  slight  strain 
on  it,  and  directs  Nos.  3  and  4  to  move  the  wheel-chocks  to  the 
rear,  an  inch  or  two  at  a  time ;  Nos.  5  and  6,  at  the  wheels* 
move  the  carriage  back  ;  Nos.  1  and  2  steady  the  piece ;  Nos.  & 
and  4  follow  up  the  movement  of  the  wheels  with  the  front 
chocks.  The  movement  is  repeated,  under  the  direction  of  the 
gunner,  until  the  carriage  is  backed  sufficiently  far  for  the  cheeks 
to  clear  the  trunnions;  No.  9,  regulating  the  position  of  the 
handspike,  supporting  it  at  each  movement  of  the  wheels,  so  as 
to  keep  its  preponderance  to  the  rear  without  lowering  it  so 
much  as  to  cause  the  key  bolts  to  interfere  with  the  piece.  The 
trail  is  then  lowered  by  means  similar  to  those  for  raising  it. 

A  turn  with  the  rope  around  some  secure  object  will  prevent 
the  danger  of  the  trail  falling  over. 

To  mount  a  siege  howitzer. 

456.  The  piece  is  standing  with  its  muzzle  on  a  shifting- 
plank,  or  on  handspikes ;  the  carriage,  unlimbered,  is  as  close  to* 
the  piece  as  practicable  and  have  the  heads  of  the  cheeks  clear 
the  trunnions  when  the  trail  is  raised;  the  wheels  are  chocked 
front  and  rear. 

The  instructor  commands : 

1.  Mount  the  piece. 

The  gunner  attaches  the  trace-rope  to  one  of  the  manoBuver- 
ing  bolts ;  Nos.  3  and  4  remove  the  cap-squares.  The  trail  is 
raised  as  explained  in  the  preceding  paragraph  until  it  is  nearly 
vertical,  Nos.  7  and  8  passing  to  the  rope  after  the  trail  is  sup- 
ported by  the  handspike.  The  trail  is  raised  slowly,  No.  10 
>eing  careful  that  it  does  not  pass  the  perpendicular,  and  No.  J> 
hat  the  supporting  handspike  is  properly  placed.  Nos.  3  and 
,  at  the  direction  of  the  gunner,  move  the  wheel-chocks  to  the 


220  MECHANICAL    MAN(EUVRES. 

front,  an  inch  or  two  at  a  time,  and  Nos.  1,  2,  5,  and  6,  at  the 
wheels,  move  forward  the  carriage,  Nos.  3  and  4  following  up 
the  wheels  with  the  rear  chocks.  The  trail  is  kept  nearly  per- 
pendicular, and  the  handspike  adjusted  by  No.  9.  These  move- 
ments are  repeated  until  the  trunnions  rest  in  their  beds,  when 
the  cap-squares  are  secured  by  Nos.  3  and  4  and  the  trail  lower- 
ed to  the  ground.  Eos.  1  and  2  assist  by  lifting  with  their 
handspikes  under  the  heads  of  the  cheeks  until  they  can  embar 
under  the  muzzle.  All  the  remaining  numbers,  except  No.  9, 
haul  on  the  rope.  As  the  weight  comes  on  the  stock,  the  men, 
in  succession,  leave  the  trace-rope  and  take  hold  of  the  stock, 
and  lower  it  by  hand  to  the  ground. 

Note. — If  the  piece  is  standing  on  the  ground,  instead  of  on  a 
plank  or  handspikes,  raise  the  trail  as  before  until  the  trun- 
nions rest  against  the  cheeks,  near  and,  if  possible,  above  the 
key  bolts;  put  the  sling-chain  (Fig.  3,  Plate  22)  around  the 
piece  from  behind,  the  ends  brought  to  the  front  under  the 
trunnions;  thence  up  around  them  and  through  the  trunnion 
beds,  where  they  are  hooked  together ;  or,  if  the  links  are  large 
enough,  catch  two  of  them  on  the  chin  bolts,  the  chain  being  in 
either  case  hauled  taut.  Lower  the  trail  to  the  ground  in  the 
inverse  manner  of  raising  it,  as  just  explained. 

If  the  piece  has  been  well  slung  the  trunnions  will  rest  on  the 
■cheeks,  in  front  of  their  beds.  To  get  them  into  their  beds,  lim- 
ber up ;  place  the  roller  under  the  bod}r ;  attach  the  trace-rope  by 
its  middle  to  the  neck  of  the  cascable,  and  take  a  turn  with  the 
•ends  around  the  axle-tree ;  raise  the  muzzle  and  slacken  care- 
fully on  the  rope  until  the  trunnions  are  in  place ;  after  which 
the  roller  is  removed. 

To  mount  the  siege  howitzer  on  its  carriage  as  a  mortar* 

45*7.  The  piece  is  lying  on  the  ground,  vent  up;  the  car- 
riage, pointing  in  the  opposite  direction,  is  placed  so  that  the 
heads  of  the  cheeks  are  about  two  yards  from  the  face  of  the 
piece,  and  then  dismounted. 

The  instructor  commands : 

1.  Mount  the  piece  as  a  mortar. 

The  muzzle  is  raised  and  a  roller  placed  under  the  piece,  as 
explained  in  par.  454.  On  soft  ground,  it  will  be  necessary  to 
place  a  shifting-plank  under  the  roller. 

The  body  of  the  carriage  is  then  moved  up  by  embarring  with 
handspikes  under  the  maneuvering  bolts  and  axle,  and  cross- 
lifting  under  the  heads  of  the  cheeks,  until  a  shifting-plank  can 
be  placed,  (by  lifting  at  the  muzzle,)  one  end  on  the  head  of  the 


SIEGE   HOWITZERS.  221 

stock,  beveled  side  up,  and  the  other  about  six  inches  in  rear  of 
the  trunnions.  At  the  time  of  placing  the  plank,  the  roller  is 
shifted  to  a  point  about  sixteen  inches  m  front  of  the  trunnions 
and  chocked.  The  plank  is  shored  up  with  the  butt  end  of  a 
handspike.  The  gunner  lays  the  middle  of  the  trace-rope  over 
the  piece  and  takes  a  round  turn  from  the  rear  upon  each  trun- 
nion with  the  ends  of  it.  (Fig.  4,  Plate  22.)  Through  the  loop 
of  these  turns,  No.  2  passes  a  handspike,  and  is  assisted  at  the 
other  end  by  No.  1  in  keeping  the  piece  from  rolling  while  it  is 
being  hauled  up  the  plank.  The  ends  of  the  rope  are  drawn 
taut,  crossed  over  the  chase,  and  manned  by  Nos.  5  to  10  upon 
their  respective  sides.  Nos.  3  and  4  embar  with  handspikes 
under  the  trunnions  until  the  piece  is  started,  and  then  shift,  as 
the  piece  ascends,  to  a  handspike  placed  crosswise  under  the 
cascable. 

The  gunner  commands:  Heave,  and  the  piece  is  hauled  and 
pushed  until  its  trunnions  rest  over  their  beds,  when  the  roller 
is  chocked  and  the  rope  removed ;  the  breech  is  raised,  the 
roller  and  plank  removed,  and  the  trunnions  lowered  into  their 
beds;  the  cap-squares  are  replaced.  By  raising  the  trail  and 
sustaining  it  in  that  position  with  blocking  or  by  a  bank  of  earth, 
an  elevation  of  about  40  degrees  can  be  obtained,  and  by  exca- 
vating under  the  breech  a  still  higher  degree.  The  trail  may 
be  used  as  a  lever  in  pointing. 

The  service  of  the  piece  is  almost  the  same  as  when  it  is 
mounted  in  the  usual  manner.  It  is  found  in  practice  that  the 
recoil  is  very  slight,  the  centre  of  gravity  being  nearly  over  the 
axle. 

To  dismount  the  howitzer. 

458.  Let  down  the  trail  and  raise  the  muzzle  until  a  wheel- 
chock,  base  up,  can  be  placed  in  each  trunnion  bed ;  raise  the 
breech  and  place  the  shifting-plank  and  roller  on  the  head  of 
the  stock ;  the  roller  should  be  just  within  the  cheeks  and  chocked 
in  rear ;  raise  the  trail  by  cross-lifting  until  the  trunnions  are 
free  from  the  key  bolts.  The  chock  of  the  roller  is  then  knocked 
ont  by  the  gunner,  and  the  piece  allowed  to  run  down  the  plank 
upon  the  ground.  The  plank  should  be  shored  up  as  before,  and 
those  near  the  piece  must  stand  clear. 


222 


MECHANICAL    MAN(EUVRBS. 


Range* 

r  of  the  8-inc/i  howitzer  mounted  as 

a  mortar. 

Charge. 

PltOJECTILE. 

Elevation. 

Range. 

Time  of 
FLionT. 

Ounces. 

Shell— Lbs. 

Degrees. 

Yards. 

Seconds. 

4 

45 

45 

330 

8 

45 

45 

620 

12 

45 

45 

1080 

14.75 

14 

45 

45 

1135 

15.37 

16 

45 

45 

1440 

16.42 

20 

45 

45 

1925 

Spherical  case  can  be  used  with  great  effect  against  troops  in 
trenches  if  made  to  burst  fifty  or  one  hundred  feet  before  reach- 
ing the  ground. 

The  charge  should  not  exceed  one-half  of  the  service  charge 
of  the  piece. 

To  dismount  a  siege  carriage  and  its  limber. 

459.  The  carriage  being  without  its  piece,  and  unlimberecL 
the  wheels  are  removed  in  succession. 

To  remove  the  right  wheel,  the  instructor  commands : 

1.  Dismount  the  right  wheel. 

No.  1  crosses  his  handspike  from  the  front,  under  the  axle- 
tree,  as  near  the  wheel  as  possible,  and  is  assisted  to  lift  by  Nos. 
2,  3,  and  4;  ETos.  5,  6,  7,  and  8  lift  at  the  other  end;  Nos.  9 
and  10  remove  the  linch-pins,  and  apply  themselves  to  the  wheel. 
The  gunner  commands  :  Heave;  the  wheel  is  removed  and  the 
axle-tree  lowered  to  the  ground,  or  on  a  block. 

The  left  wheel  is  taken  off  in  a  corresponding  manner. 

The  carriage  may  be  mounted  in  a  similar  manner. 

It  may  sometimes  be  advantageous  to  raise  the  carriage  to  the 
necessary  height  by  successive  purchases,  with  handspikes  as 
levers,  and  support  it  on  props.  The  limber  may  also  be  used 
to  lift  the  carriage,  but  it  will  generally  be  found  more  expedi- 
tious to  mount  it  as  above  described. 

The  limber  is  readily  dismounted  and  mounted  by  passing  the 
long  handspikes  between  the  sweep-bar  and  axle-tree,  the  butt 
ends  resting  on  the  splinter-bar;  six  men  lift  on  the  handspikes 
and  two  at  each  wheel. 

The  mortar-wagon  may  be  dismounted  in  like  manner,  the 


SIEGE   MORTARS.  223 

men  taking  hold  of  the  rails  and  handspikes  passed  under  the 
windlass  and  over  the  axle-tree. 

To  change  or  grease  a  wheel.  The  lifting-jack  is  applied  under 
the  axle-tree  near  the  wheel  to  be  removed,  or  the  wheel  may 
be  removed  by  using  handspikes  as  levers  and  blocks  as  fill- 
cruras,  under  the  axle-tree;  the  axle  maybe  temporarily  sup- 
ported by  a  prop. 

By  using  the  trail  as  a  lever,  a  wheel  may  be  changed,  when 
the  piece  is  unlimbered,  as  follows :  Raise  the  trail  as  in  limber- 
ing, and  place  a  prop,  about  thirty  inches  in  length,  under  the 
cheek  close  in  the  rear  of  the  axle-tree  on  the  side  on  which  the 
wheel  is  to  be  changed.  Bear  down  on  the  trail  and  the  wheel 
will  clear  the  ground. 

Mechanical  Manoeuvres  with  10-inch  Siege  Mortar. 

460.  The  implements  required  are  those  habitually  accom- 
panying each  piece  and  the  mortar-wagon,  viz.:  Four  hand- 
spikes (mortar),  two  handspikes  (maneuvering),  one  trace-rope, 
one  hammer  -  wrench,  two  long  rollers,  four  roller-chocks,  six 
wheel-chocks,  two  handspikes  (windlass). 

To  stand  the  mortar  on  one  of  its  trunnions. 

(Fig.  5,  Plate  22.) 

461.  The  mortar  is  lying  on  the  ground  or  on  its  platform. 
The  instructor  commands : 

1 .  Stand  the  mortar  on  the  right  (or  left)  trunnion. 

The  gunner  passes  the  middle  of  the  trace-rope  around  one  of 
the  trunnions  from  underneath;  the  ends  are  carried  over  the 
mortar  and  manned  by  all  the  cannoneers.  The  guuner  then 
commands :  Heave,  and  the  piece  is  pulled  over  on  its  trun- 
nion. 

To  stand  the  mortar  on  its  muzzle. 

(Fig.  6,  Plate  22.) 

462.  The  piece  is  standing  on  one  of  its  trunnions.  The 
instructor  commands : 

1.  Stand  the  mortar  on  its  muzzle. 

The  gunner  passes  the  middle  of  the  trace-rope  under  the 
mortar  in  front  of  the  trunnion  ;  carries  the  ends  back,  crosses 
them  over  the  breech  and  passes  them  to  the  front,  one  on  each 
side  of  the  upper  trunnion.    He  then  commands :  HEAVE,  and 


224  MECHANICAL    MANOEUVRES. 

4 

the  piece  is  hauled  over  on  its  muzzle  by  the  rest  of  the  detach- 
ment at  the  trace-rope. 

To  slue  the  mortar. 

463.  The  mortar  being  on  its  muzzle,  the  instructor  indi- 
cates the  direction  in  which  it  is  to  be  slued,  and  commands  : 

1.  Slue  the  mortar. 

Xos.  5  and  6  embar  against  the  trunnions  on  opposite  sides, 
and,  at  the  command  Heave  by  the  gunner,  turn  the  piece  about 
its  axis.  To  shift  the  piece  when  in  this  position,  $Tos.  5  and  6 
embar  on  the  same  side. 

To  dismount  the  mortar, 

464.  The  morbir  is  on  its  carriage,  which  is  on  the  platform 
or  on  the  ground.    The  instructor  commands : 

1.  Dismount  the  mortar. 

The  gunner,  assisted  by  No.  4,  gives  the  mortar  an  elevation 
of  twenty-one  degrees,  or,  if  no  quadrant  is  at  hand,  brings  the 
plane  of  the  face  of  the  piece  tangent  to  the  front  ends  of  the 
cheeks;  he  then  throws  the  bight  of  the  trace-rope  over  the 
middle  of  the  pipe,  and,  drawing  the  ends  through  the  loop, 
passes  them  to  the  rear  to  Nos.  7, 8,  9,  and  10,  who  haul  on  them 
with  sufficient  force,  when  the  carriage  has  been  raised,  to  keep 
it  from  falling  to  the  front ;  !No.  2  passes  a  handspike  under  the 
rear  notches  and  over  the  rope;  the  cannoneers  man  the  hand- 
spike in  the  following  order  from  right  to  left :  Nos.  1,  3,  5,  6, 
4,  2,  all  facing  to  the  front.  The  gunner  commands :  Heave  ; 
the  cannoneers  at  the  handspike  lift  on  it  until  the  face  of  the 
piece  rests  upon  the  platform  or  ground.  {Fig.  7,  Plate  22.) 
The  cap-squares  are  removed  by  Nos.  3  and  4,  assisted  by  Nos. 
1  and  2,  and  placed  in  rear  of  their  posts,  the  nuts  on  the  cap- 
squares. 

The  instructor  commands : 

l.  Lower  the  carriage. 

The  cannoneers  man  the  handspike  and  rope  as  before.  The 
gunner  commands  :  Heave.  The  cannoneers  haul  upon  the 
rope,  and  the  four  nearest  the  mortar  leave  it  in  succession,  ap- 
plying themselves  to  the  handspikes  as  the  weight  comes  upon 
it,  to  prevent  any  unnecessary  shock.  The  cap-squares  are  re- 
placed by  Nos.  3  and  4;  No.  2  removes  the  handspike,  and  the 
gunner  the  trace-rope. 


SIEGE   MORTARS.  225 

To  mount  the  mortar, 

465.  The  mortar  is  standing  upon  its  muzzle ;  the  front  of 
the  carnage  eighteen  inches  from  it,  on  the  side  opposite  the 
vent. 

The  instructor  commands : 

1.  Mount  the  mortar. 

The  cap-squares  are  removed  by  Nos.  3  and  4  and  placed,  with 
their  nuts,  in  rear  of  their  posts.  The  gunner  attaches  the  trace- 
rope  to  the  pipe,  and  the  cannoneers  apply  themselves  to  the 
rope  and  handspike  as  described  in  the  preceding  paragraph. 
The  gunner  commands :  Heave;  and  when  the  weight  of  the 
carriage  is  fairly  supported  by  the  rope,  Nos.  3  and  4  take  their 
handspikes  and,  embarring  against  the  manceuve ring  bolts,  move 
the  bed  as  may  be  necessary  until  the  trunnions  are  in  their  beds. 
Assisted  by  Nos.  1  and  2,  they  put  on  the  cap-squares. 

The  instructor  then  commands  : 

1.  Lower  the  mortar. 

Nos.  3  and  4,  facing  to  the  rear,  em  bar  with  their  handspikes 
tinder  the  cap-squares,  and  subsequently  under  the  front  notches ; 
the  other  cannoneers  apply  themselves  at  the  rope  and  hand- 
spike, and  the  mortar  is  lowered  as  described  in  par,  464. 

To  mount  the  mortar  upon  the  mortar-wagon, 

466.  The  mortar  is  on  its  carriage ;  the  carriage,  on  the  plat- 
form or  on  the  ground ;  the  trail  of  the  mortar- wagon,  its  stakes 
and  bolster  removed,  is  about  two  yards  from  the  pipe  and  per- 
pendicular thereto. 

The  instructor  commands: 

1.  Raise  the  mortar. 

Executed  as  prescribed  in  par,  464,  except  that  the  mortar 
need  not  be  given  any  particular  elevation,  and,  instead  of 
allowing  it  to  go  over  until  the  muzzle  strikes  the  ground,  the 
carriage  is  poised  in  nearly  a  vertical  position  by  Nos.  1,  2,  3,  4, 
5,  and  6,  while  Nos.  7  and  8,  embarring  with  handspikes  under 
the  stock  of  the  wagon,  guide  it  under  the  mortar  carriage  mid- 
way between  and  parallel  to  the  cheeks ;  Nos.  9  and  10  working 
at  the  wheels.  The  stock  is  run  under  the  carriage  as  far  as 
practicable  and  the  wheels  chocked  front  and  rear;  the  long 
roller  is  placed  on  it  by  the  gunner  in  such  position  that  when 
the  carriage  is  lowered  its  point  of  contact  with  the  roller  will 
be  twenty  inches  from  the  toes  of  the  shoes;  the  mortar  is  then 
lowered  upon  the  roller. 

15 


! 
i 
* 


226  MECHANICAL   MANOEUVRES. 

The  instructor  commands : 

1.  Rig  the  windlass. 

The  gunner  lays  the  middle  of  the  trace-rope  across  the  rear 
notches;  Nos.  I  and  2  pass  the  ends  underneath  and  around  the 
rear  maneuvering  bolts,  and,  carrying  them  to  the  rear,  take  two 
turns  with  them  around  the  windlass.  The  windlass  is  manned 
as  explained  in  par.  450,  and  is  worked  at  the  command  Heave 
from  the  gunner. 

As  soon  as  the  mortar  is  in  motion,  the  second  long  roller  is 
engaged  under  the  shoe,  by  Nos.  3  and  4,  twenty  inches  from 
the  lower  roller,  measuring  from  axis  to  axis.  The  lower  roller 
will  then  disengage  just  as  the  mortar  is  balanced  on  the  upper 
roller.    Nos.  5  and  6  steady  the  mortar  with  handspikes. 

As  soon  as  the  lower  roller  is  disengaged,  it  is  taken  out  by 
Nos.  3  and  4,  who  again  engage  it  twenty  inches  above  the  other 
roller.  The  mortar  is  drawn  back  on  the  last  roller  until  the 
heels  of  the  shoes  abut  against  the  hurters  on  the  rear  cross-bar 
plate.  The  roller  is  now  chocked  in  front,  and  particularly  in 
rear,  by  Nos.  3  and  4. 

The  instructor  commands : 

I.  Limber  up. 

Executed  as  in  par.  450. 

The  gunner  then  secures  the  lashing-chain. 

In  raising  the  stock,  in  limbering  and  uulimbering,  great  care 
must  be  taken  not  to  raise  it  so  high  as  to  endanger  the  over- 
turning of  the  wagon  to  the  rear. 

The  instructor  commands : 

1.  Stow  the  mortar. 

No.  4  removes  the  front  roller-chock,  and  satisfies  himself  that 
the  rear  roller-chock  is  in  place ;  Nos.  5  and  6  embar  over  the 
side  rails  and  under  the  shoos,  near  the  rear  notches,  to  cant 
the  carriage  to  the  front ;  Nos.  1  and  2  ease  away  gentl y,  and 
permit  the  carriage  to  move  forward  on  the  roller  until  the 
front  notches  are  over  the  front  cross-bar  plate.  If  the  car- 
riage does  not  move  far  enough  forward  on  the  roller  after 
canting,  Nos.  5  and  6  embar  over  the  side  rails  and  under  the 
front  notches,  and  pinch  the  carriage  forward  to  its  place.  The 
roller  is  then  removed  from  the  rear,  and  the  carriage  lowered 
onto  the  wagon  by  repeated  purchases,  the  disengaged  roller- 
chocks  and  bolster  being  placed  by  the  gunner  as  fulcrums  on 
the  rear  of  the  wagon.  If  the  mortar  is  to  travel,  its  carriage  is 
securely  lashed  to  the  wagon. 


SIEGE  MORTARS.  227 

467.  The  most  convenient  way  of  carrying  the  implements, 
is  to  fit  a  bed  to  the  mortar-wagon.  The  bed  is  made  of  stout 
boards  about  a  foot  wide ;  those  for  the  sides  are  held  in  place 
by  rope  beckets  passed  through  auger  holes  in  the  boards  and 
around  the  stakes  of  the  wagon;  the  end  boards  fit  between 
cleats  nailed  to  the  ends  of  the  side  boards;  the  whole  forming 
a  box  about  seven  feet  long,  witli  a  width  equal  to  the  widtli  of 
the  wagon.  Slots  are  cut  in  the  side  boards  for  the  maneuver- 
ing bolts,  which  project  slightly  beyond  the  side  rails  of  the 
wagon. 

To  dismount  the  mortar  from  the  wagon, 

468.  The  mortar  is  unlashed ;  the  implements,  bolster,  and 
stakes  of  the  wagon  are  removed. 

The  instructor  commands : 

1.  Dismount  the  mortar. 

Nos.  5  and  6  embar  over  the  side  rails  and  under  the  rear 
notches,  using  chocks  and  bolster  as  f  ulcrums,  and  by  repeated 
purchases  raise  the  mortar  carriage  until  a  long  roller  can  be 
placed  under  it  with  the  points  of  contact  two  feet  from  the  toes 
of  the  shoes. 

The  instructor  then  commands : 

1.  Rio  the  windlass. 

The  gunner  attaches  the  trace-rope,  and  the  windlass  is  rigged 
as  explained  in  par.  450.  At  the  command  HEAVE  from  the 
gunner,  the  mortar  is  drawn  back  against  the  hurters,  Nos.  5 
and  6  embarring  under  the  shoes  and  over  the  side  rails,  to  ease 
the  carriage  when  it  cants  to  the  rear;  Nos.  3  and  4  chock  the 
roller  front  and  (especially)  rear. 

The  instructor  commands : 

1.  Unlimber. 

Executed  as  explained  in  par.  451. 
The  instructor  commands : 

1.  Lower  the  mortar. 

Nos.  1  and  2  slack  off  on  the  rope,  and  the  mortar  is  eased 
down  the  stock.  The  second  long  roller  is  engaged  under  the 
front  of  the  carriage  as  soon  as  the  mortar  cants  to  the  front, 
so  that  the  distance  between  the  rollers,  measuring  from  axis  to 
axis,  shall  be  twenty  iuches;  the  rollers  arc  shifted  in  this  man- 
ner by  Nos.  3  and  4  until  the  carriage  rests  on  the  ground; 
Nos.  5  and  6,  with  their  handspikes,  steady  the  mortar  while 


228  MECHANICAL   MANCBUVRES. 

being  eased  down  the  stock;  Nos.  3  and  4  unchock  the  wheels, 
and  the  wagon  is  run  back  by  Nbs.  5  and  6  at  the  stock,  and 
Nos.  7,  8,  9,  and  10  at  the  wheels.  The  rope  is  removed  by  Nos. 
1  and  2  and  the  gunner.  The  long  roller  is  removed  as  it  was 
placed  under  the  carriage.    (Par.  466.) 

To  mount  and  dismount  the  8-inch  mortar  on  mortar-wagon. 

Executed  in  a  manner  similar  to  that  explained  for  the  10- 
inch  mortar.  * 

For  transportation,  three  8-inch  mortars  can  be  carried  on  the 
mortar- wagon.  They  are  stowed  transversely  to  the  wagon,  one 
pointing  to  the  right  and  two  to  the  left,  or  vice  versa,  and 
securely  lashed  in  this  position. 

To  dismount  the  13-inch  mortar ;  and  to  mount  it. 

469.  Implements :  Eight  whole  blocks,  eight  half  blocks,  four 
quarter  blocks,  four  handspikes  (manoeuvering),  one  sledge-ham- 
mer, four  chocks  (roller),  one  quadrant,  one  hammer-wrench,  one 
nut-wrench  (large),  two  nut-wrenches  (small),  one  two-foot  rule. 

The  instructor  commands : 

1.  Prepare  to  dismount  the  mortar. 

Remove  all  implements,  and  place  them  outside  the  platform  ; 
take  off  the  steps,  diagonal  braces,  eccentric  sockets,  wheels,  axle, 
and  cap-squares ;  give  the  mortar  an  elevation  of  five  degrees, 
in  order  that  it  will  rest  level  when  on  the  blocks. 

1.  Dismount  the  mortar. 

(Figs.  1  and  2,  Plate  23.)  Erabar  with  the  long  handspikes 
under  the  rear  notches,  using  blocks  as  fulcrnms,  and  by  succes- 
sive purchases  raise  the  carriage  until  a  whole  block  can  be 
placed  under  the  shoes,  its  front  directly  beneath  the  rear  tran- 
som ;  place  two  whole  and  one  quarter  block  under  the  mortar, 
in  rear,  and  the  same  in  front  of  the  trunnions;  lower  the  car- 
riage gently  onto  the  platform,  being  carefill  to  chock  the  mor- 
tar as  soon  as  it  touches  the  blocks;  remove  the  rear  transom 
and  pipe,  and  lay  the  cheeks  clown  upon  the  ground. 

1.  Prepare  to  mount  the  mortar. 

Raise  the  cheeks  and  place  them  with  the  trunnion  beds  under 
the  trunnions;  put  in  the  rear  transom  and  pipe. 

1.  Mount  the  mortar. 

Embar  as  before  under  the  rear  notches,  raising  the  carriage 
until  the  mortar  is  lifted  clear  of  the  blocks  ;  remove  the  blocks, 


13-INCH   MORTAR.  229 

and  lower  the  carriage  gently  to  the  platform.  Give  the  mortar 
an  elevation  of  45  degrees,  and  replace  the  cross-braces,  axle, 
wheels,  eccentric  sockets,  steps,  cap-squares,  and  implements. 

Iti  this  manoeuvre  care  must  be  taken  to  raise  the  rear  part  of 
the  cheeks  equally,  so  that  the  great  weight  of  the  mortar  may 
not  sway  the  cheeks  sideways  and  warp  the  carriage  out  of  true 
shape. 

470.  When  a  garrison  gin  is  available,  the  best  method  is 
to  make  use  of  it.  The  block  is  hooked  into  a  clevis  attached  to 
the  clevis  lug.  When  there  is  no  clevis  lug  a  bail  must  be  used. 
It  is  necessary  to  remove  the  upper  step  or  transom  of  the  car- 
riage, and  level  the  mortar,  before  hoisting. 

In  the  absence  of  a  gin,  the  mortars  may  be  dismounted  with 
the  hydraulic-jack  and  blocks.  The  steps,  diagonal  braces,  and 
transoms,  excepting  the  pipe,  are  removed,  and  the  muzzle  de- 
pressed two  degrees,  the  breech  resting  on  the  scaffolding  and 
chocked  on  each  side.  The  jack  is  placed  under  the  muzzle,  and 
the  mortar  is  raised  until  its  weight  is  off  the  trunnion  beds.  A 
scaffolding  under  the  muzzle  sustains  the  mortar  in  this  position, 
and  the  cheeks  are  taken  apart  and  removed. 

To  place  the  13-inch  mortar  and  carriage  on  rollers, 

4?  1.  The  following  implements  are  necessary :  Pour  rollers 
(78  inches  long),  four  whole  blocks,  four  half  blocks,  two  quarter 
blocks,  and  four  chocks  (roller). 

Embar  under  the  rear  notches  perpendicular  to  the  cheeks, 
and  raise  the  rear  of  the  carriage  until  a  quarter  block  can  be 
inserted  under  each  shoe.  These  quarter  blocks  are  worked  to 
the  front  by  successive  purchases  until  half  blocks  can  be  in- 
serted in  place  of  the  quarter  blocks.  The  half  blocks  are  worked 
to  the  front  as  before  until  a  roller  can  be  inserted  under  the 
shoes. 

This  roller  is  worked  to  the  front  until  it  is  nearly  under  the 
eccentric  axle,  and  another  roller  is  placed  behind  it  near  the 
heels  of  the  shoes.  The  rollers  are  chocked  front  and  rear. 
Embar  under  the  front  notches  and  cant  the  mortar  to  the  rear 
on  both  rollers. 

The  mortar  may  then  be  moved  short  distances  by  attaching 
blocks  and  tackle  to  it.  Way-planks  are  placed  on  the  ground 
for  the  rollers  to  run  on. 

To  raise  a  13-inch  mortar  from  the  ground  and  place  it  on  blocks, 

{Fig.  3,  Plate  23.) 

472«  Build  a  scaffolding  of  blocks,  about  a  yard  from  the 
piece,  on  each  side  of  it ;  lay  a  stout  skid  across  the  mortar  on 


230  MACHINES  AND  APPLIANCES 

these  scaffolds,  and  lash  the  mortar,  by  means  of  sling-chains, 
to  this  skid.  If  there  is  no  clevis»lug  on  the  mortar,  trunnion 
rings  or  a  bail  must  be  used.  Apply  the  jack  alternately  under 
the  ends  of  the  skid,  and  raise  them  a  few  inches  at  a  time,  each 
time  blocking  up  on  the  scaffolds. 

By  this  means  the  mortar  can  be  raised  and  blocks  placed 
under  it.  If  a  jack  is  not  available,  a  stout  lever  will  answer  to 
raise  the  ends  of  the  skid. 

To  transport  a  13-inch  mortar  on  sling-carts, 
(Fig.  4,  Plate  23.) 

473.  The  piece  is  raised,  as  just  explained,  on  blocks  about 
fifteen  inches  from  the  ground.  Two  sling -carts  (large)  are 
placed,  one  in  front  and  the  other  in  rear,  with  their  poles  point- 
ing in  opposite  directions  and  their  wheels  about  eighteen  inches 
apart.  Upon  the  sling-carts  place  two  heavy  skids,  with  a  space 
of  about  six  inches  between  them.  Across  the  skids  place  a 
stout  beam,  around  which  suspend  the  mortar  by  means  of  sling- 
chains  passing  down  between  the  skids  to  the  clevis  lug,  bail,  or 
trunnion-chains.  The  blocks  underneath  the  mortar  are  re- 
moved either  with  a  jack  or  by  means  of  a  lever. 

The  pole  of  one  of  the  carts  is  attached  to  a  field  limber,  to 
which  horses  are  hitched.  When  the  ground  is  soft,  way-planks 
should  be  placed  under  the  cart-wheels. 

To  obtain  greater  freedom  of  motion  for  turning,  a  temporary 
bolster  should  be  placed  on  the  front  cart.  A  hole  is  made 
through  the  bolster  for  the  screw  of  the  cart  to  pass  through  r 
and  to  hold  the  bolster  to  the  axle-tree.  Notches  should  be 
made  in  the  skids  to  fit  the  bolsters  of  the  carts,  to  keep  them 
from  slipping. 


MACHINES  AND   APPLIANCES   FOR   MOVING 

HEAVY  ARTILLERY. 

474.  The  machines  and  appliances  usually  employed  for 
moving  heavy  artillery  are : 

Ropes,  blocks,  and  Railway  truck.  Hand-cart. 

tackle.  Cradle.  Blocks  (whole,  half, 

Gins.  Gun-lift.  and  quarter). 

Hydraulic-jacks.  Capstan.  Way-planks. 

Sling-carts.  Derrick.  Pinch-bars. 

Casemate  truck.  Shears.  Mortar-wagon. 

Truck- wagon.  Blocks  and  skids.  Collar. 


FOR   MOVING   HEAVY   ARTILLERY.  231 

These,  with  the  implements  used  in  the  mechanical  manoeu- 
vres with  siege  pieces,  are  sufficient  to  manage  the  heaviest  pieces 
of  artillery  in  all  cases  which  ordinarily  present  themselves  in 
service. 

4*75.  All  implements  and  machines,  before  being  used,  should 
be  most  carefully  examined  in  every  detail,  to  see  that  they  are 
serviceable  and  suitable  for  the  operation  to  be  performed. 
None  should  be  put  to  uses  for  which  they  are  not  intended, 
nor  subjected  to  strains  they  are  not  constructed  to  bear. 

It  must  be  borne  in  mind  that  the  giving  way  of  one  part 
breaks  and  destroys  other  parts,  frequently  to  an  extent  not 
readily  repaired,  and,  furthermore,  endangers  those  working 
at  the  manoeuvre.  Heavy  weights  must  never  be  allowed  to 
drop,  even  for  the  shortest  distances;  they  must  be  lowered  to 
rest  with  a  gentle  motion,  and  at  the  same  time  chocked  to  pre- 
vent rolling  or  sliding.  In  hoisting,  they  must,  when  practica- 
ble, be  closely  followed  up  with  blocks  and  chocks  to  guard 
against  any  possible  giving  way.  All  motions  with  heavy  bodies 
must  be  slow,  so  as  not  to  generate  momentum. 

Supports  must  have  a  firm  base,  and  scaffolding  a  level  foun- 
dation, and  be  built  up  vertically.  All  holdfasts  must  be  secure 
beyond  possibility  of  giving  Way. 

Cordage. 

(Plates  24,  25,  26,  27,  28.) 

476.  A  rope  is  composed  of  threads  of  hemp  or  other  fibrous 
material.  These  threads  are  called  yarns.  A  number  of  these 
yarns  twisted  together  form  a  strand,  and  three  or  more  strands 
twisted  together  form  a  rope. 

'The  ropes  in  ordinary  use  are  composed  of  three  strands  laid 
right-handed,  or,  as  it  is  called,  with  the  sun.  Occasionally  a 
large  rope  will  be  found  laid  up  in  four  strands,  also  with  the  sun. 
Tliis  is  generally  used  for  stationary  rigging,  such  as  shrouds, 

fuys,  heavy  gun-slings,  &c,  and  is  sometimes  called  shroud  laid. 
mall  halyards  are  sometimes  laid  with  four  strands  and  a  core ; 
this  kind  of  rope  runs  more  smoothly  and  wears  longer. 

Cable-laid  rope  is  composed  of  nine  strands,  and  is  made  by 
first  laying  up  three  ropes  of  three  strands  each,  with  the  sun, 
and  then  laying  the  three  ropes  up  together  into  one,  against 
the  sun. 

Right-hand  rope  must  be  coiled  with  the  sun,  and  cable-laid 
rope  against  the  sun. 

The  size  of  rope  is  always  given  in  inches  and  fractions,  and 
is  measured  on  the  circumference,  for  the  reason  that  it  is  seldom 


232  MACHINES    AND   APPLIANCES. 

possible  to  get  a  squarely-cut  end  in  order  to  measure  the  diam- 
eter. In  making  requisitions  for  rope,  it  should  be  clearly  indi- 
cated that  this  measure  is  the  one  considered. 

Spun-yarn  is  made  by  twisting*  together  veiy  loosely  two  or 
more  well-tarred  yarns,  and  is  designated  by  the  number  of 
yarns ;  as,  two-yarn,  three-yarn,  &c.  It  is  used  for  serving,  seiz- 
ings, stops,  &c,  and  is  very  pliable. 

Marline  is  also  made  of  tarred  yarns,  but  is  tightly  twisted, 
and  is  much  harder  and  smoother  than  spun-yarn.  It  is  not  fit 
for  serving  when  the  rope  served  is  to  be  bent  up,  as  it  is  not 
pliable;  enough  to  cover  the  rope  in  such  cases. 

4oHH,   The  bight  of  a  rope  is  any  part  not  an  end. 

A  bight  is  formed  by  bending  or  doubling  the  rope  so  as  to 
form  a  loop. 

This  distinction  should  be  particular^'  noted,  and  the  two 
terms  should  not  be  confounded. 

The  interstices  between  the  strands  of  a  rope  are  called  the  jawr 
and  rope  is  called  long  or  short  jawed  as  it  is  loosely  or  tightly 
laid  up  together. 

Those  ropes  which  are  stationary  are  called  standing  rigging; 
as,  guys  for  a  gin.  gun-slings,  &c.  Those  which  run  through 
blocks  or  pulleys,  such  as  gin-falls,  trace-ropes,  &c,  are  running 


riggino:. 


4T8.  Worming  a  rope  is  filling  up  the  divisions  between  the 
strands  by  passing  spun-yarn  along  them,  to  render  the  surface 
smooth  for  parceling  and  serving. 

Parceling  a  rope  is  wrapping  narrow  strips  of  canvas  about  it, 
well  tarred,  in  order  to  secure  it  from  being  injured  by  rain 
water  lodging  between  the  parts  of  the  service  when  worn.  The 
parceling  is  put  on  with  the  lay  of  the  rope.  Parceling  is  also 
used  to  prevent  chafing  or  cutting  of  a  rope  when  a  strain  is 
brought  against  a  rough  surface  or  sharp  edge.  For  this  pur- 
pose old  rope  or  canvas  wound  around  is  sufficient. 

Serving  is  the  laying  on  of  spun-yarn  or  other  small  stuft'in  turns 
round  the  rope,  close  together,  and  hove  taut  by  the  use  of  a 
serving  board  for  small  rope  and  serving  mallet  for  large  rope. 
Small  ropes  are  sometimes  served  without  being  wormed,  as  the 
crevices  between  the  strands  are  not  large,  enough  to  make  the 
surface  very  uneven;  but  a  large  rope  is  always  wormed  and 
parceled  before  being  served.  The  service  is  put  on  against  the 
lay  of  the  rope. 

Whipping  is  securing  the  end  of  a  rope  with  twine  to  prevent 
it.  from  fraying  out.  For  temporary  use  it  may  be  done  by  wind- 
ing twine  about  the  end  of  the  rope  and  securing  the  end  of  the 
twine  by  passing  it  under  two  or  more  turns  of  the  twine  and 


CORDAGE.  233 

pulling  it  tight.  It  is  better,  however,  to  secure  the  ends  by  sew- 
ing tliem  through  the  rope,  so  that  each  stitch  lies  in  the  division 
between  two  strands.    This  is  called  a  sewed  whipping. 

479*  Splicing  is  putting  the  ends  of  ropes  together  by  open- 
ing the  strands  and  placing  them  into  one  another,  or  by  putting 
the  strands  of  the  ends  of  a  rope  between  those  of  the  bight. 

A  short  splice.  Unlay  the  strands  for  a  convenient  length ; 
then  take  an  end  in  each  hand,  place  them  one  within  the  other, 
and  draw  them  close.  Hold  the  end  of  one  rope  and  the  three 
strands  which  come  from  the  opposite  rope  fast  in  the  left  hand, 
or  if  the  rope  be  large,  £top  them  down  to  it  with  a  rope-yarn. 
Take  the  middle  strand,  which  is  free,  pass  it  over  the  strand 
which  is  first  next  to  it,  then  through  under  the  second  and  out 
between  the  second  and  third  from  it,  then  haul  it  taut.  Pass 
each  of  the  six  strands  in  the  same  manner;  first  those  of  one 
end  and  then  those  of  the  other.  The  same  operation  may  be 
repeated  with  each  strand,  passing  each  over  the  third  strand 
from  it,  under  the  fourth,  and  through ;  or,  as  is  more  usual, 
after  the  ends  have  been  stuck  once,  untwist  each  strand,  di- 
vide the  yarns,  pass  one-half  as  above  described,  and  cut  off  the 
other  half;     This  tapers  the  splice. 

A  long  splice.  Unlay  the  ends  of  two  ropes  to  a  distance  three 
or  four  times  greater  than  for  a  short  splice,  and  place  them 
within  one  another  as  for  a  short  splice.  Unlay  one  strand  for 
a  considerable  distance  and  fill  up  the  interval  which  it  leaves 
with  the  opposite  strand  from  the  other  rope.  Twist  the  ends 
of  these  two  together,  then  do  the  same  with  two  more  strands. 
The  two  remaining  strands  are  twisted  together  in  the  place 
where  they  were  first  crossed.  Open  the  two  last-named  strands, 
divide  in  two,  take  an  overhand  knot  with  the  opposite  halves, 
and  lead  the  ends  over  the  next  strand  and  through  the  second 
as  the  whole  strands  were  passed  for  the  short  splice.  Cut  off 
the  other  two  halves.  Do  the  same  with  the  others  that  are 
placed  together,  dividing,  knotting,  and  passing  them  in  the 
same  manner.  Before  cutting  off  any  of  the  half  strands^  the 
rope  should  be  got  well  upon  a  stretch.  Sometimes  the  whole 
strands  are  knotted,  then  divided,  and  the  half  strands  passed 
as  above  described.  This  splice  does  not  increase  the  diameter 
of  the  rope,  and  is  used  for  splicing  a  fall  or  other  rope  that  runs 
through  blocks  or  pulleys. 

An  eye-splice.  Unlay  the  end  of  a  rope  for  a  short  distance 
and  lajr  the  three  strands  upon  the  standing  part,  so  as  to  form 
an  eye.  Put  the  first  end  through  the  strand  next  to  it.  Put 
the  second  end  over  that  strand  and  through  the  second,  and  put 
the  remaining  end  through  the  third  strand  on  the  other  side  of 


234  MACHINES   AND   APPLIANCES. 

the  rope.  Taper  them,  as  in  the  short  splice,  by  dividing  the 
strands  and  sticking  them  again.  This  is  used  to  form  a  perma- 
nent loop  in  the  end  of  a  rope. 

A  grommet.  Take  a  strand  just  unlaid  from  a  rope,  with  all 
its  turns  in  it,  and  form  a  ring  of  the  size  you  wish  by  putting 
the  end  over  the  standing  part.  Then  take  the  long  end  and 
carry  it  twice  round  the  ring  in  the  crevices,  following  the  lay 
until  the  ring  is  complete ;  then  take  an  overhand  knot  with  the 
two  ends,  divide  the  yarns,  and  stick  them  as  in  a  long  splice. 
Used  for  a  trunnion  loop  for  rolling  or  sluing  a  gun. 

480.  Two  half  hitches.  Pass  the  end  of  a  rope  round  the 
standing  part  and  bring  it  up  through  the  bight.  This  i3  a  half 
hitch.  Take  it  round  again  in  the  same  manner  for  two  half 
hitches. 

A  clove  hitch  is  made  by  passing  the  end  of  a  rope  round  a  spar, 
over,  and  bringing  it  under  and  round  behind  its  standing  part, 
over  the  spar  again  and  up  through  its  own  part.  It  may  then, 
if  necessary,  be  stopped  or  hitched  to  its  own  part;  the  only 
difference  between  two  half  hitches  and  a  clove  hitch  being 
that  one  is  hitched  round  its  own  standing  part  and  the  other 
is  hitched  round  a  spar  or  another  rope. 

Bound  turn  and  two  half  hitches.  Take  a  round  turn  around 
the  stakes  or  posts,  and  secure  the  end  by  two  half  hitches 
around  the  standing  part.  This  is  very  useful  in  securing  the 
guys  of  the  gin  to  the  stakes. 

A  bowline  lcnot.  Take  the  end  of  .a  rope  in  your  right  hand 
and  the  standing  part  in  3ronr  left;  lay  the  end  over  the  stand- 
ing part,  and  with  the  left  hand  make  a  bight  of  the  standing 
part  over  it;  take  the  end  under  the  lower  standing  part  up 
over  the  cross,  and  down  through  the  bight.  This  is  very  useful 
in  forming  a  temporary  ej*c  at  the  end  of  a  rope. 

Square  knot.  Take  an  overhand  knot  round  a  spar;  take  an 
end  in  each  hand  and  cross  them  on  the  same  side  of  the  stand- 
ing part  upon  which  they  came  up;  pass  one  end  round  the 
other,  and  bring  it  up  through  the  bight.  This  is  sometimes 
called  a  reef  knot.  If  the  ends  are  crossed  the  wrong  way, 
sailors  call  it  a  granny  knot. 

A  timber  hitch.  Take  the  end  of  a  rope  round  a  spar,  lead  it 
under  and  over  die  standing  part,  and  pass  two  or  more  round 
turns  around  its  own  part;  pass  the  first  turn  over  the  end  part 
instead  of  through  the  bight,  as  in  a  half  hitch.  Used  in  secur- 
ing the  ends  of  the  trace-ropes  to  the  manoeuvering  bolts. 

A  rolling  hitch.  Pass  the  end  of  a  rope  round  a  spar ;  take  it 
round  the  second  time,  nearer  to  the  standing  part;  then  -carry 
it  across  the  standing  part,  over  and  round   the  spar  and  up 


CORDAGE.  235- 

through  the  bight.  A  strap  or  a  tail  block  is  fastened  to  a  rope- 
by  this  hitch.  Used  in  shifting  the  fall  from  one  end  of  the 
windlass  to  the  other.    (See  nipper  and  screw.) 

A  blackball  hitch.  Form  a  bight  by  putting  the  end  of  a  rope 
across  and  under  the  standing  part;  pnt  the  hook  of  a  tackle 
through  it,  the  centre  of  the  bight  resting  against  the  back  of 
the  hook,  and  the  end  jammed  in  the  bight  of  the  hook  by  the 
standing  part  of  the  rope. 

A  caVs-paw.  Make  a  large  bight  in  a  rope,  and  spread  it  open, 
putting  one  hand  at  one  part  of  the  bight  and  the  other  at  t lie* 
other,  and  letting  the  standing  part  and  end  come  together; 
turn  the  bight  over  from  you  three  times,  and  a  small  bight  will 
be  formed  in  each  hand ;  bring  the  two  small  bights  together, 
and  put  the  hook  of  a  tackle  through  them  both.  This  is  very 
useful  in  applying  a  purchase  or  tackle  to  the  fall  of  another. 

A  sheet  bend  (weaver's  knot).  Pass  the  end  of  a  rope  up- 
through  the  bight  of  another,  round  both  parts  of  the  other,  and 
under  its  own  part.  This  does  not  jam,  and  is  useful  in  tying 
two  ropes  together. 

Carrick  bend.  Form  a  bight  in  a  rope  and  lay  the  end  across 
the  standing  part;  stick  the  bight  of  another  rope  up  through 
the  loop  thus  formed,  and  carry  the  end  over  the  end  of  the 
first  rope,  under  the  standing  part,  and  through  the  loop  formed 
by  its  own  bight ;  stop  each  end  to  its  own  standing  part. 

Fisherman's  bend  (anchor  knot).  Take  two  turns  around  the 
gnn-slins:  or  spar  with  the  end  of  the  rope  ;  hitch  the  end  around 
the  standing  part  and  through  both  turns,  and  then  pass  the 
end  over  the  second  and  under  the  first  turn. 

A  sheep  shank.  Make  two  Ion?  bights  in  a  rope  which  shall 
overlay  one  another;  take  a  half  hitch  over  the  end  of  each 
bight  with  the  standing  part  which  is  next  to  it.  Used  to  shorten 
a  rope  temporarily. 

A  marlinspike  hitch.  Lay  the  marlinspike  upon  the  seizing 
stuff,  and  bring  the  end  over  the  standing  part  so  as  to  form 
a  bight ;  lay  this  bight  back  over  the  standing  part,  putting  th^ 
marlinspike  down  through  the  bight,  under  the  standing  part, 
and  up  through  the  bight  again.  Very  useful  in  putting  on 
lashings,  <fcc. 

Stopping  is  fastening  two  parts  of  a  rope  together,  as  for  a 
round  seizing,  without  a  crossing  or  riding. 

Nippering  is  fastening  them  by  taking  turns  crosswise  between 
the  parts  to  jam  them,  and  sometimes  with  a  round  turn  before 
eacli  cross.  These  are  called  racking  turns.  Pass  riders  over 
these  and  fasten  the  end.  This  is  a  convenient  way  to  secure  a 
fall  while  it  is  being  shifted  on  the  windlass. 


236  MACHINES   AND   APPLIANCES. 

A  screw  is  applied  by  weaving  a  light  strap  through  the  differ- 
ent parts  of  a  fall,  bringing  the  two  ends  together,  and  screwing 
the  whole  up  tight  by  means  of  a  stick  or  bar  passed  through 
the  bights. 

A  strap,  or  sling,  is  formed  by  knotting  or  splicing  together  the 
<ends  of  a  short  strand  or  rope.  It  is  used  for  hooking  tackles 
into. 

Pointing.  Unlay  the  end  of  a  rope  and  stop  it ;  take  out  as 
many  yarns  as  are  necessary,  and  split  each  yarn  in  two,  and 
take  two  parts  of  different  yarns  and  twist  them  up  taut  into 
nettles;  the  rest  of  the  yarns  are  combed  down  with  a  knife ; 
lay  half  the  nettles  down  on  the  scraped  part,  the  rest  back  upon 
the  rope,  and  pass  three  turns  of  twine  taut  round  the  part 
where  the  nettles  separate,  and  hitch  the  twine,  which  is  called 
the  warp;  lay  the  nettles  backwards  and  forwards  as  before, 
passing  the  warp  each  time.  The  ends  may  be  whipped  and 
snaked  with  twine,  or  the  nettles  hitched  over  the  warp  and 
hauled  taut.  The  upper  seizing  must  be  snaked.  If  the  upper 
part  is  too  weak  for  pointing,  put  in  a  piece  of  stick.  This  is  an 
elaborate  way  of  whipping  ropes,  and  requires  considerable  prac- 
tice. 

Frap.  To  pass  a  rope  around  a  lashing  to  keep  the  turns 
together. 

Seizing  a  rope  is  connecting  the  two  parts  with  smaller  rope, 
or  spun-yarn.  Take  a  piece  of  spun-yarn  and  double  it ;  pass  the 
bight  under  the  two  parts  of  the  rope  to  be  seized;  put  both 
-ends  through  it  and  haul  taut,  using  a  lever  applied  with  the 
marlinspike  hitch ;  separate  the  ends,  pass  them  around  the  rope 
in  opposite  directions  until  enough  turns  are  taken,  hauliug 
each  turn  taut,  and  seeing  that  they  lay  close  and  smooth. 
Cross  the  seizing  by  passing  the  ends  in  opposite  directions  be- 
tween the  ropes  and  around  the  seizing,  and  finish  with  a  square 
knot. 

A  lashing  is  applied  on  the  same  principles.  After  sufficient 
turns  have  been  taken,  the  lashing  is/rapped  by  taking  the  ends 
around  the  turns,  hauling  them  close  together,  and  making  the 
lashing  tighter,  of  course. 

To  pass  a  shear  lashing.  Middle  the  lashing  and  take  a  turn 
round  both  legs  at  the  cross;  pass  one  end  up  and  the  other 
down,  around,  and  over  the  cross,  until  half  of  the  lashing  is 
expended ;  then  ride  both  ends  back  again  on  their  own  parts 
and  knot  them  in  the  middle ;  frap  the  first  and  riding  turns 
together  on  each  side  with  sennit.  This  will  be  useful  in  rigging 
shears  for  hoisting  guns,  when  a  gin  is  not  available.  Any  two 
spars  that  will  support  the  weight  can  be  used. 


CORDAGE. 


■2o7 


To  sling  a  barrel  with  both  heads  in,  or  a  box.  Lay  it  on  its 
side ;  lay  ;i  long  strap  under  it,  spreading  the.  parts ;  pass  one 
bight  through  Clio  other,  on  top  of  the  barrel,  ami  hook  on  to  It. 

If  one  head  of  the  barrel  is  out.  Stand  the  barrel  up;  put 
one  part  of  a  strap  under  the  middle  of  the  bottom ;  t:ikt-  a  half 
bitch  over  the  top  with  cacti  part,  the  hitches  exactly  opposite 
to  each  other  and  Just  above  the  upper  bilge  hoops.  Hook  on 
to  the  bight  aa  before.  Those  hoops  applied  near  the  ends  of  a 
barrel  are  the  il  chime."  and  those  near  the  centre  the  "bilge" 
hoops. 

481.  Hemp  rope  is  about  one-third  stronger.  Due  allowance 
lias  been  made  for  loss  of  strength  by  wear  anil  tear. 

Look  for  the  weight  to  be  raised,  or  the  next  larger,  In  the 
column  headed  with  the  number  of  sheaves  in  the  purchase  or 
tackle.  The  circumference  of  the  rope  required  will  be  found 
on  the  same  line  in  the  left-hand  column. 


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18! 
M 
115 

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1,755 

3,743 
3,349 
5,376 

b!»ss 

Hi;  a  5  Li 
OB 

:S1 
» 

2» 

180 

167 

IT5 
'40 
158 

IK 

IS 

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aw - 

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4X 

4« - 

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IS  :>:-;i 
10,805 
Sl.lil 

23.1(10 
i+.S-il 
33,448 

•V 

238 


MACHINES   AND   APPLIANCES. 


To  ascertain  the  strain  in  pounds  which  a  rope  will  bear  with- 
out breaking,  multiply  the  square  of  the  circumference  by  the  tab- 
ular number. 


Description. 

• 

1 

B  • 

D 

White. 

Tabbed. 

3-strand. 

4-strand. 

3-strand. 

4-etrand. 

Inches. 

2.5  to   6 
6     to  8 
2.5  to   6 
6    to  12 

1140 

1090 

810 

760 

1330 

1260 

950 

835 

850 
825 

1000 
940 

For  ropes  in  daily  use*  the  unit  should  be  diminished  one-third 
to  meet  the  reduction  in  strength  by  wear  and  exposure. 

A  safe  general  rule  for  all  ropes  is  this  :  One-fourth  the  square 
of  the  circumference  gives  the  breaking  weight  in  tons  of  2000 
pounds. 

When  using  tackles,  multiply  the  weight  thus  found  by  one- 
half  the  number  of  sheaves  in  the  blocks. 

Straps  are  applied  by  passing  them  around  the  object,  putting 
one  bight  through  the  other,  and  hooking  to  this ;  or,  after  put- 
ting it  through,  winding  all  the  strap  around  the  rope  or  spar, 
and  hooking  to  both  bights. 

Preservation  in  store.  Ropes  should  be  placed  in  the  upper 
stories  of  buildings,  coiled  up  and  labeled  ;  large  ropes  on  skids, 
allowing  free  circulation  of  air ;  small  ropes  hung  tup  to  4he 
joists,  on  pins  or  hooks.  Ropes  should  not  be  coiled  until  per- 
fectly dry ;  they  should  be  uncoiled  every  year,  and  stretched 
out  for  several  dajrs  in  the  dry  season.  Ropes  long  in  store  lose 
their  strength. 

Blocks,  Tackles,  &c. 

(Plates  29  and  30.) 

482.  Blocks  are  of  two  kinds,  made  and  mortised.  A  made 
block  consists  of  four  parts  :  the  shell,  or  outside ;  the  sheave,  or 
wheel  on  which  the  rope  turns ;  the  pin,  or  axle  on  which  the 
wheel  turns;  and  the  strap,  either  of  rope  or  iron,  which  encir- 
cles the  whole  and  keeps  it  in  its  place.  The  sheave  is  generally 
strengthened  by  letting  in  a  piece  of  iron  or  brass  at  the  centre, 


BLOCKS,  TACKLES,  ETC.  289 

called  a  bush.    Nearly  all  heavy  blocks  for  ordnance  purposes 
are  made  with  iron  shells  and  brass  sheaves. 

A  mortised  block  is  made  of  a  single  block  of  wood,  mortised 
out  to  receive  a  sheave. 

All  blocks  are  single,'  double,  or  threefold,  according  to  the 
number  of  sheaves  in  them. 

There  are  blocks  that  have  no  sheaves,  to  wit:  a  buWs-eye^ 
which  is  a  wooden  thimble  without  a  sheave,  having  a  hole 
through  the  centre  and  a  groove  around  it;  and  a  dead-eye, 
which  is  a  solid  block  of  wood  made  in  a  circular  form,  with  a 
groove  round  it,  and  three  holes  bored  through  it,  for  the  lan- 
yards to  reeve  through. 

Snatch  blocks  are  single  blocks,  with  a  notch  cut  in  one  cheek, 
just  below  the  sheave,  so  as  to  receive  the  bight  of  a  fall  with- 
out the  trouble  of  reeving  and  un reeving  the  whole.  They  are 
generally  iron-bound,  and  have  a  hook  at  one  end. 

A  tail  block  is  a  single  block,  strapped  with  an  eye-splice,  and 
having  a  long  end  left  by  which  to  make  the  block  fast  tempo- 
rarily to  the  rigging.  This  tail  is  usually  sclvaged,  or  else  the 
strands  are  opened  and  laid  up  into  sennit,  as  for  a  gasket. 

483.  A  tackle  is  a  purchase  formed  bjf  reeving  a  rope  through 
two  or  more  blocks,  for  the  purpose  of  hoisting. 

A  whip  is  the  smallest  purchase,  and  is  made  by  a  rope  rove 
through  one  single  block. 

A  gun-tackle  purchase  is  a  rope  rove  through  two  single  blocks 
and  made  fast  to  the  strap  of  the  upper  block.  The  parts  of  all 
tackles  between  the  fasts  and  sheave  are  called  the  standing 
parts;  the  parts  between  sheaves  are  called  running  parts;  and 
the  part  which  is  taken  hold  of  in  hoisting  is  called  the  fall. 

A  whip  upon  whip  is  where  the  block  of  one  whip  is  made  fast 
to*  the  fall  of  another. 

A  luff-tackle  purchase  is  a  single  and  a  double  block ;  the  end 
of  the  rope  being  fast  to  the  upper  part  of  the  single  block,  and 
the  fall  coming  from  the  double  block.  A  luff*  tackle  upon  the 
fall  of  another  luff  tackle  is  called  luff  upon  luff. 

A  watch  tackle,  or  tail  tackle,  is  a  luff-tackle  purchase,  with  a 
hook  in  the  end  of  the  single  block  and  a  tail  to  the  upper  end 
of  the  double  block.  One  of  these  purchases  with  a  short  fall  is 
kept  on  deck,  at  hand,  in  merchant  vessels,  and  is  used  to  clap 
upon  standing  and  running  rigging,  and  to  get  a  strain  upon 
ropes. 

A  runner  tackle  is  a  luff  applied  to  a  runner,  which  is  a  single 
rope  rove  through  a  single  block,  hooked  to  a  thimble  in  the  eye 
of  a  pennant. 

A  single  Burton  is  composed  of  two  single  blocks,  with  a  hook 
in  the  bight  of  the  running  part.    Reeve  the  end  of  your  rope 


240  MACHINES   AND   APPLIANCES. 

through  the  upper  block,  and  make  it  fast  to  the  strap  of  the  fl3r 
block ;  then  make  fast  your  hook  to  the  bight  of  the  rope,  and 
reeve  the  other  end  through  the  fly  block  for  a  fall.  The  hook 
is  made  fast  by  passing  the  bight  of  the  rope  through  the  eye  of 
the  hook  and  over  the  whole.  This  is  a  very  quick-working 
tackle  and  a  strong  purchase.    Used  for  hoisting  entirely. 

When  a  very  heavy  weight  is  to  be  raised,  the  standing  parts 
should  be  attached  to  the  slings  by  a  fisherman's  bend,  instead 
of  to  the  block. 

The  size  of  'blocks  is  expressed  by  the  length  of  the  shell  in 
inches ;  if  ropes  of  unusual  size  are  to  be  used,  it  should  be  spe- 
cified in  making  requisitions  for  blocks. 

Tackles  are  also  designated  by  the  number  of  sheaves  em- 
ployed; as,  twofold  (two  single  blocks),  threefold  (double  and 
single  block),  &c. 

A  mousing  is  a  seizing  placed  around  a  hook  to  prevent  it  from 
spreading  or  unhooking,  and  should  always  be  applied  as  fol- 
lows: Take  several  turns  of  yarn  or  spun-yarn  around  the  point 
and  back  of  the  hook,  and  frap  the  ends  around  all  the  turns. 

The  bight  of  a  hook  is  the  middle  of  the  bend  of  the  hook  part. 

Useful  suggestions. 

484.  A  tackle  is  said  to  be  utwo  blocks"  when  the  entire 
fall  is  hauled  through,  so  that  the  blocks  are  in  contact. 

To  overhaul  a  tackle  is  to  separate  the  blocks.  This  is  best 
done  as  follows  :  Hook  the  upper  block  firmly,  or  let  one  or  two 
men  hold  it;  let  one  or  more  men  take  hold  of  the  lower  block 
and  haul,  while  one  man  lights  the  fall  through  the  upper  block 
by  hauling  the  running  part  through  it.  If  necessary,  let  an- 
other hand  light  the  second  part  through. 

Rope  should  always  be  stopped  up,  either  with  the  end  or  with 
rope-yarn  stops,  to  prevent  it  getting  into  a  snarl.  When  using 
ropes  for  hauling,  they  should  never  be  dragged  upon  the  ground. 

To  stop  up  a  coil  of  rope  with  the  end.  Lay  off  two  or  three 
turns  of  the  coil  and  take  a  clove  hitch  around  all  parts  of  one 
side  of  the  coil.  Do  the  same  on  the  other  side.  If  the  rope 
should  be  rove  in  a  tackle,  run  it  "two  blocks"  and  make  the 
first  hitch  around  the  fall  between  the  blocks. 

Before  reeving  a  rope  in  a  block,  the  turns  should  be  carefully 
taken  out  to  prevent  twisting  when  the  weight  is  lifted.  This 
is  done  by  stretching  the  rope  out  to  its  full  length  and  turning 
it  in  the  opposite  direction  to  that  in  which  it  is  laid  up,  until 
all  the  stiffness  disappears. 

Blocks  should  be  overhauled  very  often  to  see  that  the  sheaves 
are  working  properly  on  the  pin  and  that  they  work  smoothly. 
If  they  do  not,  turn  the  pin  end  for  end,  and  rub  a  little  black- 


BLOCKS,  TACKLES,  ETC. 


241 


lead  (graphite)  on  them  to  lubricate  them,  also  on  the  sides  of 
the  sheaves  where  they  rub  against  the  shell. 

When  hoisting  with  tackles  they  should  never  be  allowed  to 
twist.  If  they  show  a  tendency  to  do  so,  insert  a  bar  in  the 
block  or  sling,  and  use  it  as  a  lever  to  hold  it  straight. 

It  frequently  happens  that  the  men  cannot  apply  their  full 
strength  in  the  direction  in  which  it  would  be  most  effective. 
In  such  cases  hook  a  single  block  to  some  object  about  two  feet 
above  ground  and  reeve  the  end  of  the  fall  through  it,  so  that 
the  men  can  add  their  strength  to  their  weight  and  more  men 
can  apply  themselves. 

Never  trust  the  suspension  of  a  weight  to  holding  it  by  the 
unaided  strength  of  men.  If  it  is  possible  to  get  a  turn  around 
any  fixed  object,  even  in  raising  or  hauling  a  weight,  it  is  best 
to  take  a  turn,  as  all  that  is  gained  is  then  saved. 

Always  select  such  blocks  that  the  fall  will  run  freely  through 
them  and  not  ride  upon  the  edges  of  the  sheaves.  If  it  does,  it 
will  be  certain  to  cut.  The  rope  should  not  quite  fill  the  score 
or  groove  on  the  sheave.  In  this  way  excessive  friction  is  avoid- 
ed.    The  sailor's  maxim  is,  u Small  ropes  and  big  blocks.9' 

The  power  gained  by  using  tackles  is  as  follow* : 

Two  single  blocks,  or  gun  tackle — nearly  doubled. 

Luff  tackle  (double  and  single  block)— doubled.  If  the  doable 
block  is  movable — trebled. 

Two  double  blocks — power  X  3J. 

Double  and  treble  blocks — power  x  4. 

Two  treble  blocks — power  x  4 J. 

Whip  upon  whip,  single  Burton — trebled. 

When  one  tackle  is  applied  to  the  fall  of  another,  the  power 
obtained  is  found  by  multiplying  their  respective  values  together. 

No  advantage  is  gained  by  using  a  greater  number  of  sheaves 
than  two  treble  blocks  in  one  fall. 

Weight  and  strength  of  iron  chains. 


Diaxn'r  of 
iron   for 
links. 

Weight  of 
one   foot 
of  chain. 

Breaking 
weight. 

Proof 
weight. 

Diana' r  of 
iron   tor 
links. 

Weight  of 
one  foot 
of  chain. 

Breaking 
weight. 

Proof 
Weight. 

Inch. 

Lbs. 

Lbs. 

Lbs. 

Inch. 

Lbs. 

Lbs. 

Lbs. 

0.1875 

0.325 

2,240 

948 

0.625 

4.217 

26,880 

10,304 

0.25 

0.65 

4,256 

1,680 

0.6875 

4.833 

32,704 

12,544 

0.8125 

0.967 

6,720 

2,461 

0.75 

5.75 

38,752 

15,232 

0.375 

1.383 

9,634 

3,581 

0.8125 

6.667 

45,696 

17,696 

0.4375 

1.767 

13,216 

5.152 

0.875 

7.5 

51,744 

20,384 

0.5 

2.633 

17,248 

6,720 

0.9375 

9.333 

58,464 

23,520 

0.5625 

3.333 

21,728 

8,512 

1. 

10.817 

65,632 

26,880 

16 


242  MACHINES   AND   APPLIANCES. 

The  Gin. 

{Plate  31.) 

485.  A  gin  is  a  tripod  formed  of  three  poles.  Two  of  these 
poles,  called  legs,  are  joined  together  by  braces  of  wood  or  iron, 
and  contain  between  them  the  windlass.  The  third  pole  is  called 
the  pry-pole,  and  is  joined  to  the  legs,  at  the  top,  by  a  bolt. 
This  bolt  supports  a  clevis,  to  which  the  upper  block  of  the  tackle 
is  hooked. 

The  windlass  is  worked  by  two  handspikes  fitting  into  brass 
sockets,  one  at  each  extremity  of  the  windlass ;  the  operation  of 
the  handspike  is  made  continuous  by  the  action  of  a  pawl  at- 
tached to  the  socket  on  the  ratchet  of  the  windlass. 

To  prevent  the  legs  and  pry-pole  from  sinking  into  the  ground, 
or  injuring  the  pavement  of  casemates,  stout  pieces  of  wood, 
called  shoes,  are  placed  under  them.  The  hoisting  apparatus 
consists  of  two  blocks,  through  which  the  fall  is  rove.  The  fall 
is  wound  two  or  more  times  around  the  windlass. 

There  are  three  kinds  of  gins  used  for  artillery  purposes :  the 
siege,  the  garrison,  and  the  casemate. 

The  last  two  differ  from  each  other  only  in  height;  the  first 
differs  from  the  others  in  construction  and  size.  Piper's  gin  is 
an  improved  modification  of  the  siege  gin. 

When  the  gin  is  put  together  and  raised,  that  part  included 
between  the  legs  and  pry-pole  is  called  the  inside,  the  outside 
being  the  part  without  the  legs ;  the  right  corresponding  to  the 
right  hand  of  a  man  standing  at  the  middle  and  outside  of  the 
windlass,  facing  towards  it,  the  left  corresponding  to  his  left 
hand. 

486.  The  detachment  is  composed  of  one  chief,  one  gunner, 
and  ten  cannoneers.  The  odd  numbers  are  placed  on  the  right 
and  the  even  numbers  on  the  left  side  of  the  gin,  all  faciug  in- 
wards ;  Nos.  1  and  2  opposite  and  one  yard  outside  of  the  foot  of 
the  pry-pole ;  No.  9  outside  of  and  near  the  foot  of  the  right  leg; 
No.  10  outside  of  and  near  the  foot  of  the  left  leg;  Nos.  3,  5, 
and  7  are  between  Nos.  1  and  9,  dressing  on  them  and  dividing 
the  intervening  space  into  equal  distances;  Nos.  4,  C,  and  8  oc- 
cupy similar  positions  with  respect  to  Nos.  2  and  10.  In  assem- 
bling the  gin,  the  gunner  and  Nos.  1  and  2  bring  up  the  pry-pole ; 
Nos.  3,  5,  and  7  the  right  leg,  and  Nos.  4,  6,  and  8  the  left  leg; 
Nos.  9  and  10,  the  windlass.  The  gunner  superintends  putting 
together  the  head,  and  the  chief-of-detachment  the  placing  of 
the  windlass.  The  braces  are  brought  up  and  adjusted  to  their 
places  by  Nos.  5,  6,  7,  and  8. 

The  gunner,  assisted  by  the  most  expert  cannoneers,  reeves 


THE  GIN.  243 

the  fall,  slings  the  piece,  and  attends  to  all  knottings  and  lash- 
ings. 

In  working  the  windlass,  Nos.  I  and  2  hold  on  to  the  fall  and 
take  up  the  slack ;  Nos.  7  and  9  work  at  the  light,  and  Nos.  8 
And  10  at  the  left  handspike,  Nos.  7  and  8  being  next  the  wind- 
lass. All,  except  the  old-pattern  siege  gin,  are  put  together  and 
hoisted  by  raising  the  head  and  bringing  up  the  foot  of  the  pry- 
pole  towards  the  feet  of  the  legs. 

487.  The  siege  gin  (old  pattern)  is  put  together  with  the  out- 
side of  the  legs  and  windlass  downwards  and  the  pry-pole  rest- 
ing on  the  top.  (Fig.  1,  Plate  32.)  It  has  no  clevis,  as  other 
gins,  and,  instead  of  an  upper  block,  two  sheaves  are  inserted 
between  the  legs  and  secured  by  the  bolt  holding  together  the 
legs.  The  head  of  the  pry-pole  is  terminated  by  a  flat  piece  of 
Iron,  which  fits  between  the  heads  of  the  legs  above  the  sheaves, 
-and  is  secured  by  another  bolt. 

This  gin  further  differs  from  others  in  having  three  wooden 
braces  instead  of  two  of  iron.  It  has  the  disadvantage  of  being 
•exceedingly  ill-contrived  and  unhandy. 

To  put  the  siege  gin  (old  pattern)  together. 

48 8 •  The  different  parts  of  the  gin  having  been  brought  to 
the  place  designated,  the  instructor  commands : 

1.  Assemble  the  gin. 

This  is  executed  as  indicated  in  pars.  486  and  487. 
The  gin  being  together  and  lying  on  the  ground,  the  instruct- 
or commands : 

1.  Reeve  the  fall. 

Nos.  1  and  2  raise  the  pry-pole  until  it  clears  the  sheaves.  The 
gunner,  receiving  from  Nos.  3  and  4  one  end  of  the  fall,  passes 
it  through  the  left  sheave  from  below  and  hands  it  back  to  them. 
They  pass  it  through  the  sheave  of  the  single  pulley,  (hooked  for 
convenience  on  the  middle  brace,)  and  return  it  to  the  gunner, 
who  passes  it  through  the  right  sheave  from  below,  and  gives  it 
to  No.  3,  by  whom  it  is  secured  by  wrapping  it  around  the  middle 
brace.  If  the  gin  has  been  raised,  the  instructor  gives  the  same 
-command,  when  the  gunner,  mounting  upon  the  upper  brace, 
receives  from  Nos.  3  and  4  one  end  of  the  fall,  which  he  passes 
-over  the  left  sheave  from  without  to  within.  The  fall  is  then 
reeved  in  the  manner  prescribed. 

To  raise  the  gin. 
The  instructor  commands : 

1.  Raise  the  gun. 
Nos.  1  and  2  take  hold  of  the  handle  of  the  pry-pole ;  Nos.  9 


244 


MACHINES   AND   APPLIANCES. 


and  10  each  hold  down  the  foot  of  a  leg  to  prevent  it  from  slip- 
ping"; Nos.  3  and  4  lift  at  the  head,  and  Nos.  5,  6,  7,  and  8  ap- 
ply themselves  at  the  legs  on  their  respective  sides.  The  gunner 
commands:  Heave;  the  gin  is  raised ;  Nos.  1  and  2  carry  out 
the  foot  of  the  pry-pole  about  twelve  feet  from  the  windlass  and 
place  under  it  a  shoe.    A  shoe  is  likewise  placed  under  each  leg. 

To  move  the  gin  when  raised. 

The  instructor  wishing  to  move  the  gin  a  short  distance,  indi- 
cates the  direction  and  commands : 

1.  Move  the  gin,  2.  March. 

Nos.  1  and  2  apply  themselves  at  the  handle  of  the  pry-pole; 
Nos.  9  and  10  each'  place  a  handspike  under  the  windlass  from 
without,  and  near  the  legs ;  Nos.  7  and  8  assist  to  lift  at  these 
handspikes  from  within ;  at  the  command  March,  all  move  in 
the  direction  indicated. 

To  lower  the  gin. 

The  gin  is  lowered  in  a  similar  manner,  hut  by  inverse  means 
to  that  prescribed  for  raising  it.  Nos.  1  and  2  raise  the  pry-pole 
and  assist  in  easing  the  gin  to  the  ground,  the  outside  down- 
wards. 

489.  The  following  are  the  kinds,  dimensions,  weights,  and 
strengths  of  ropes  usualljr  required  for  the  different  kinds  of 
gins: 


Designation. 

• 

a 

a 

Weight. 

• 

Rbmabks. 

S 

o 

©«W 

g 

o 

© 

&  © 

a* 

«M 

o 

Gin  fall  (garrison 
Gun-sling  (siege.).... 

Inch. 
4.25 

6 

6 

3.25 
1.75 

Feet. 
75 

120 

26 

30 

10 

100 

• 

Lb.  Oz. 
5      4 

10      6 

10     6 

3     1 
11 

Lb.  Oz. 

67    8 

208 

44    9 

15    5 

1    2 

11 

Lbs. 
8,064 

16,128 

16,128 

4,760 
5,371 

> 
Hemp. 

Hemp. 

")  An  eye  at  one 

1     end,   served 

|     with    leath- 

J     er.    Hemp. 

Manila. 

Hemp. 

Hemp. 

THE  GIN.  245 

To  mount  a  siege  gun. 

490.  It  is  immaterial  upon  which  side  of  the  piece  the  legs 
of  the  gin  are  placed,  but,  for  uniformity,  they  are  generally 
placed  on  the  right.  The  gun  is  suspended  either  by  a  sling  or 
by  a  bail ;  the  latter  is  preferable.  It  consists  of  a  stout  piece 
of  iron  (Fig.  2,  Plate  32),  passing  like  a  handle  over  the  piece 
and  fitting  against  the  ends  of  the  trunnions,  to  which  it  is  fast- 
ened by  iion  bolts  passing  through  the  ends  of  the  bail  into  holes 
bored  for  the  purpose ;  one  in  the  end  of  each  trunnion. 

A  clevis,  attached  to  the  middle  of  the  bail,  gives  a  place  for 
hooking  the  lower  block  of  the  tackle. 

The  gin  being  raised  and  placed  with  its  tackle  directly  over 
the  trunnions,  and  the  foot  of  the  pry-pole  about  twelve  feet 
from  the  lower  brace,  the  instructor  commands : 

1.  Sling  the  piece. 

"No.  1  puts  a  handspike  in  the  bore,  small  end  foremost ;  No. 
2  passes  the  eye  or  loop  end  of  the  sling  around  the  knob  of  the 
cascable ;  No.  1  passes  the  other  end  under  the  handspike  in  the 
bore,  and  hands  it  to  No.  2,  who  draws  it  through  the  loop ;  the 
gunner  fastens  it  either  by  a  knot  or  with  a  lashing-rope,  and 
then  hooks  the  single  pulley  to  the  sling  just  in  rear  of  the  trun- 
nions, fastening  the  standing  end  of  the  fall  to  the  sling  near  the 
same  place ;  Nos.  1  and  2  pass  the  running  end  of  the  fall  from 
the  outside  under  the  windlass,  aud  take  three  turns  with  it 
around  the  left  of  the  windlass,  and  hold  on  by  the  running  end 
or  slack,  No.  1  being  nearest  the  windlass ;  the  gunner  applies 
himself  to  the  handspike  in  the  bore  to  steady  the  piece ;  Nos. 
7, 8,  9,  and  10  apply  themselves  at  the  windlass  handspikes.  All 
being  in  readiness,  the  instructor  commands : 

1.  Hoist  away. 

The  windlass  is  worked  until  the  piece  is  high  enough  to  admit 
the  carriage  under  it.    The  instructor  then  commands : 

1.  Halt,  2.  Bun  up  the  carriage. 

All  the  men,  except  Nos.  1  and  2,  bring  up  the  carriage,  as 
explained  in  par.  435,  placing  the  trunnion  beds  directly  under 
the  trunnions. 

The  instructor  then  commands : 

1.  Slack  off. 

Nos.  1  and  2  slack  of  the  fall  slowly ;  the  gunner  steadies  the 
piece  by  means  of  the  handspike  in  the  bore,  and  the  piece  is 


246  MACHINES   AND   APPLIANCES. 

lowered  into  its  position  in  the  trunnion  or  traveling  beds ;  Nos. 
3  and  4  put  on  the  cap-squares  and  key  them. 

Note. — When  the  bail  is  used,  it  is  attached  by  the  same  num- 
bers as  for  the  sling.  If  it  is  not  convenient  to  sling  the  piece  in 
the  manner  prescribed,  it  may  be  slung  by  a  rope  passed  around! 
each  trunnion,  and  the  ends  fastened  together  on  top  of  the 
piece ;  or  trunnion  rings  may  be  used.  Hook  the  pulley  to  this- 
sling  or  to  the  trunnion  rings ;  bear  down  with  one  or  two  met* 
on  the  handspike  in  the  bore  to  balance  the  piece,  and  when  it  is 
raised  sufficiently  high  run  the  carriage  under  it,  and  place  a 
handspike  in  the  trunnion  beds  and  a  block  on  the  stock.  (For 
casemate  or  barbette  carriages,  upon  scaffolds  built  of  blocks- 
•under  the  breech  and  chase.)  Lower  the  gun,  the  trunnions  di- 
rectly over  the  trunnion  beds,  until  the  piece  rests  on  the  block 
and  on  the  handspike.  Remove  the  sling  or  rings  from  the 
trunnions  and  run  the  carriage,  with  the  gun  on  it,  back  until 
the  head  of  the  cheeks  are  in  rear  of  a  perpendicular  let-fall  from 
the  head  of  the  gin.  Pass  the  sling  around  the  chase,  hook  the 
pulley  to  it,  and  work  the  gin  until  the  weight  no  longer  bears^ 
on  the  handspike  in  the  trunnion  beds ;  remove  the  handspike, 
and  lower  the  trunnions  to  their  places;  bear  down  oh  the  muz- 
zle, and  remove  the  block  from  under  the  breech. 

To  dismount  a  siege  gun. 

491.  The  gin  is  placed  in  the  same  position  with  reference 
to  the  piece  as  prescribed  for  mounting  it.  The  instructor  com- 
mands : 

1.  Sling  the  piece. 

The  cap-squares  are  removed,  the  piece  is  slung,  and  the  run- 
ning end  of  the  fall  passed  around  the  windlass  as  prescribed  for 
mounting  it. 

The  commands  Hoist  away,  Halt,  Run  out  the  carriage,  and 
Slack  off  are  then  given  and  executed  in  the  manner  already 
prescribed. 

To  sling  and  hoist  a  siege  mortar  mounted  on  its  carriage. 

492.  A  gun-sling  or  a  sling-chain  is  used.  In  either  case,, 
the  middle  of  it  is  passed  under  the  front  notches ;  the  ends  car- 
ried up,  and,  crossing  over  the  top  of  the  mortar,  are  passed  mi* 
der  the  rear  notches.  The  gin  is  erected  over  the  mortar  and 
the  lower  block  of  the  tackle  hooked  into  the  sling  where  it 
crosses  the  top  of  the  mortar.  The  mortar  is  raised  and  lowered 
upon  a  wagon  in  the  manner  prescribed  for  a  gun. 


THE  GIN.  247 

To  shift  the  fall. 

493.  As  the  turns  gain  once  the  diameter  of  the  fall  at  each 
revolution  of  the  windlass,  they  will,  when  the  weight  has  been 
raised  a  considerable  height,  come  against  the  opposite  leg. 
The  instructor  then  commands :  1.  Halt,  2.  Shift  the  fall. 
The  gunner  mounts  to  a  position  where  he  can  reach  the  run- 
ning part  of  the  fall,  and  firmly  applies  a  nipper  to  two  of  the 
parts  as  explained  in  par.  480.  The  instructor  then  commands : 
Ease  away.  Nos.  1  and  2  slack  off  and  shift  the  turns  on  the 
windlass  to  the  opposite  end ;  they  then  tighten  up  the  fall, 
the  nipping  is  removed  by  the  gunner,  and  the  manoeuvre  is  re- 
sumed. 

Piper" s  gin. 

494.  In  this  gin,  the  windlass  is  attached  by  placing  it  in 
windlass  seats  of  peculiar  construction,  and  is  secured  in  posi- 
tion by  keepers  attached  to  the  legs.  The  keepers  are  placed 
under  the  axles  of  the  windlass.  Two  stay-chains  connect  the 
pry-pole  and  legs  at  the  upper  brace-bauds,  and  prevent  them 
from  spreading.  They  also  serve  to  connect  the  parts  for  trans- 
portation. Two  braces  (upper  and  lower)  connect  and  secure 
the  legs  when  the  gin  is  put  together,  and  serve  to  distinguish 
the  right  from  the  left  leg — the  long  brace  being  permanently 
attached  to  the  right  and  the  short  brace  to  the  left  leg.  The 
clevis  and  clevis  bolt  are  attached  to  the  head  of  the  pry-pole 
with  keys  which  secure  the  clevis  bolt  when  the  gin  is  assem- 
bled; double  and  single  blocks,  with  fall,  are  used.  This  gin 
was  designed  by  the  late  Captain  J.  W.  Piper,  fifth  artillery. 

Length  of  legs 13  feet  8  inches. 

Length  of  pry-pole 13  feet  8  inches. 

Weight  of  gin 365  pounds. 

Weight  of  windlass 88  pounds. 

Weight  of  block  and  fall 100  pounds. 

Weight  of  bail  and  dowels 41  pounds. 

The  parts  are  estimated  to  be  sufficiently  strong  to  bear  a 
weight  of  5000  pounds.  The  advantages  of  this  gin  are,  its 
superior  lightness  and  portability,  and  its  great  facility  of  being 
assembled,  taken  apart,  packed  up,  and  transported. 

The  different  parts  having  been  brought  to  the  place  designa- 
ted, the  gin  is  put  together,  raised,  lowered,  and  taken  apart  by 
the  following  commands  from  the  instructor :  Assemble  the 
gin.  Nos.  1  and  2  place  in  position  the  pry-pole ;  STos.  3  and  5 
place  in  position  the  right,  and  Nos.  4  and  6  the  left  leg ;  the 
gunner,  assisted  by  Nos.  3  and  4,  attaches  the  clevis  and  clevis 


248  MACHINES  AND  APPLIANCES. 

bolt,  assembles  the  head  of  the  gin,  and  hooks  on  the  block  and 
fall ;  Nos.  5  and  6  attach  the  braces. 

The  gin,  in  this  position,  is  lying  extended  upon  the  ground, 
with  the  inside  downwards. 

The  instructor  commands : 

Raise  the  gin. 

Nos.  9  and  10  hold  down  the  feet  of  the  legs  to  prevent  them 
from  slipping ;  Nos.  1  and  2  push  up,  applying  themselves  at 
the  handle  of  the  pry-pole.  The  other  numbers  apply  them- 
selves as  in  par.  488. 

The  gunner  commands :  Heave. 

The  gin  is  raised  and  the  pr}r-pole  brought  up  to  within  about 
twelve  feet  from  the  legs ;  Nos.  3  and  4  attach  the  stay-chains 
on  their  respective  sides,  and  Nos.  9  and  10  put  in  the  windlass. 

To  move  the  gin  when  raised. 
Executed  as  explained  in  par.  488. 

To  lower  the  gin. 

The  gin  is  lowered  in  a  similar  manner,  but  by  inverse  means 
to  that  prescribed  for  raising  it. 

The  staj'-chains  are  unhooked  and  windlass  removed  before 
lowering. 

#  To  take  the  gin  apart. 

The  gin  is  taken  apart  in  a  similar  manner,  but  by  inverse 
means  to  that  prescribed  for  putting  it  together,  and  is  stowed 
for  transportation  by  lashing  together  the  legs,  pry-pole,  and 
windlass  with  the  stay-chains. 

The  application  of  this  gin  to  the  mechanical  manoeuvres  of 
siege  ordnance  is  similar  to  that  prescribed  for  the  siege  gin  (old 
pattern). 

Garrison  and  Casemate  Gins. 

495.  The  garrison  and  casemate  gins  differ  from  the  siege 
gin  in  having  two  cross-bars  of  iron  instead  of  the  three  wooden 
cross-bars,  and  in  having  the  pry-pole  inserted  between  the  legs, 
which  are  kept  together  by  the  clevis  bolt.  The  upper  block 
(generally  treble)  is  hooked  to  the  clevis. 

The  casemate  gin  is  made  shorter  than  the  garrison  gin,  bo 
that  it  may  be  hoisted  in  casemates.  With  the  jguns  now  usually 
mounted  in  casemates,  it  is  essential  to  use  a  bail  for  slinging,  in 


GARRISON  AND  CASEMATE  GINS.  249 

order  to  gain  the  necessary  distance  from  the  head  of  the  gin  for 
the  working  of  the  tackle. 

The  gin  is  put  together  across  the  piece,  or  on  the  ground  near 
It,  and  raised  by  moving  tip  the  legs  and  pry-pole  towards  each 
other  as  explained  in  preceding  paragraph.  The  pry-pole  has 
<leats  nailed  to  it  to  enable  a  man  to  mount  to  the  head  of  the 
gin  to  hook  on  the  block  and  to  reeve  the  fall. 

In  raising  it,  Nos.  9  and  10,  each  with  a  handspike,  brace 
against  the  lower  cross-bar  near  the  legs  to  prevent  them  from 
slipping ;  Nos.  1  and  2  hold  down  the  foot  of  the  pry-pole,  and 
at  thp  same  time  push  up  by  the  handle.  The  remaining  num- 
bers take  hold  to  lift  by  hand  near  the  head. 

The  gunner  commands :  Heave;  the  head  of  the  gin  is  raised 
as  high  as  the  men  can  lift,  and  the  pry-pole  pushed  up ;  Nos.  3 
and  4  go  to  the  assistance  of  Nos.  1  and  2  at  the  handle  of  the 
pry-pole ;  Nos.  5,  6,  7,  and  8  lift  at  the  legs  on  their  respective 
sides.  The  gunner  repeats  heave  until,  by  successive  efforts, 
the  gun  is  raised.  The  pry- pole  should  be,  for  the  garrison  gin, 
about  seventeen  feet  from  the  legs ;  for  the  casement  gin,  about 
thirteen  feet. 

The  gin  is  next  placed  over  the  piece  by  moving  the  legs  and 
the  pry-pole  each  a  short  distance  at  a  time.  To  prevent  them 
from  spreading  too  much,  a  lashing  is  passed  from  the  pry-pole 
to  the  upper  cross-bar. 

To  reeve  the  fall. 

Fasten  one  end  of  a  trace-rope  to  the  upper  block  by  passing 
it  through  the  shell  of  the  block.  An  expert  man  ascends  the 
pry-pole  to  the  head,  and  passes  the  free  end  of  the  rope  through 
the  clevis,  from  whence  it  is  earned  down  to  the  windlass,  where 
a  couple  of  turns  are  taken.  By  heaving  on  the  windlass,  the 
block  is  raised  and  the  hook  passed  through  the  clevis,  with  its 
point  towards  the  pole.  The  fall  is  rove  as  explained  in  par. 
488.  The  upper  block  may  be  hooked  to  the  clevis  and  raised 
with  the  gin  ;  the  fall  may  also  be  rove  and  the  whole  raised  to- 
gether. The  extra  weight  thus  given  makes  the  gin  more  diffi- 
cult to  lift. 

The  gin  is  lowered  by  gradually  drawing  out  the  pry-pole  un- 
til the  men  can  get  near  enough  towards  the  head  to  support  it ; 
it  is  then  lowered  upon  the  piece  or  on  the  ground,  as  the  case 
may  be. 

To  mount  a  casemate  gun. 

496.  The  carriage  is  traversed  to  one  side,  and  the  gun— on 
blocks,  or  on  the  truck — is  near  the  middle  of  the  casemate,  the 


250  MACHINES   AND   APPLIANCES. 

muzzle  towards  the  embrasure ;  the  gin  is  over  the  gun  and 
■carriage ;  the  latter  on  the  side  of  the  pry-pole  ;  the  axis  of  the 
trunnions  is  horizontal  and  directly  under  the  head  of  the  gin. 

The  gun  is  slung  bjr  means  of  a  bail  or  trunnion  rings.  The 
gin  is  worked  until  the  gun  is  raised  sufficiently  high,  when  the 
chassis  is  traversed  under  it,  and  the  gun  carriage  so  placed  that 
the  trunnion  beds  come  exactly  under  the  trunnions.  The  gun 
is  then  lowered  to  its  place,  the  sling  removed,  and  the  gin  car- 
ried to  the  next  casemate. 

To  prevent  the  pavement  from  being  injured  by  the  points,  a 
shoe  is  placed  under  each  foot. 

To  dismount  the  gun. 

Executed  in  the  inverse  manner  to  that  prescribed  for  mount- 
ing.   The  gun  is  placed  on  the  truck,  or  on  blocks. 

The  windlasses  of  gins  should  never  be  painted,  as  paint  is 
liable  to  cause  surging  when  easing  off'  the  fall,  and  surging  is 
certain  to  cause  breaking  of  parts. 

To  dismount  a  barbette  gun. 

497.  The  safest  and  best  method  of  dismounting  the  15-inch 
gun  is  by  means  of  blocks,  as  hereafter  explained,  or  with  the 
gun-lift.  It  may,  however,  be  dismounted  by  using  two  garri- 
son gins,  one  of  which  is  erected  over  the  cascable  and  the  other 
over  the  chase,  midway  between  the  trunnions  and  the  muz- 
zle. 

The  piece  is  slung  by  means  of  chains  similar  to  those  used 
with  the  gun-lift.  The  blocks  and  fall  are  those  usually  furnished 
with  the  gin.  Everything  should  be  perfectly  sound  and  in  good 
condition ;  for  it  must  be  borne  in  mind  that  the  weight  upon 
each  gin  is  one-third  more  than  it  was  originally  intended  to 
bear. 

Ten-inch  guns,  and  all  below,  are  mounted  and  dismounted 
by  means  of  one  garrison  gin.  To  dismount  a  10-inch  gun,  run 
it  from  battery  as  in  loading ;  erect  the  gin  over  the  piece  so 
that  the  head  will  be  directly  over  the  trunnions;  the  sling, 
which  is  made  of  9-inch  rope,  is  attached  by  passing  the  bight 
of  it  around  the  neck  of  the  cascable,  carrying  the  end  forward 
over  the  piece  and  under  the  end  of  a  roller  thrust  in  the  muz- 
zle ;  thence  back,  passing  it  through  the  eye  of  the  sling,  draw- 
ing it  tight,  bending  it  into  a  knot,  and  securing  it  with  marline. 
In  all  cases,  gun-slings  should  be  drawn  as  tightly  as  possible  ; 
otherwise  the  tackle  will  be  block  and  block  before  the  trunnions 
are/free  from  the  carriage.  It  may  be  necessary,  especially  with 
a  new  sling,  to  take  several  lifts  upon  it  in  order  to  take  the 


GARRISON  AND  CASEMATE  GINS.  251 

stretch  out  of  it ;  after  each  lift  the  slack  is  taken  up.  A  trace- 
rope  is  attached  to  the  muzzle  as  a  guy ;  the  tackle  is  hooked 
to  the  sling  immediately  over  the  axis  of  the  trunnions;  the 
gin  is  worked  as  explained  in  par.  490  until  the  trunnions  are 
sufficiently  above  their  beds  to  permit  the  top-carriage  being 
shoved  forward  from  under  the  piece.  This  done,  the  chassis  is 
traversed,  towards  the  pry-pole,  from  under  the  gun  ;  the  latter 
is  then  lowered  upon  blocks  and  the  gin  removed.  Whea 
hoisting  the  piece,  the  traverse-wheels  should  not  be  chocked. 

To  dismount  the  top-carriage  from  the  chassis. 

498*  Back  the  limber  of  a  field-piece  against  the  rear  ends 
of  the  chassis  rails.  The  ammunition  chest  being  removed,  ft 
couple  of  large  blocks  are  placed  on  the  limber;  the  counter- 
hurters  are  removed,  and  the  top-carriage  pulled  and  shoved 
back,  off  the  chassis,  onto  the  blocks  upon  the  limber.  If  there 
is  no  limber  or  similar  carriage  available,  a  scaffolding  of  blocks 
is  built  at  the  rear  end  of  the  chassis,  and  the  carriage  moved 
back  upon  it ;  from  this  it  is  easily  lowered  to  the  ground. 

To  remove  the  chassis  from  the  platform. 

499.  Take  out  the  pintle  key ;  pry  and  block  up  the  front 
end  of  the  chassis  until  it  is  clear  of  the  pintle ;  the  chassis  is 
then  overturned  by  attaching  a  trace-rope  to  the  far  side  of  it- 
chocking  the  near  traverse-wheel,  and  hauling  on  the  rope  until 
the  chassis  is  on  its  side;  the  rope  is  then  carried  around  to  the 
other  .side  and  the  chassis  eased  down  upon  blocks  placed  for  its- 
reception.  From  this  position  it  may  be  moved,  if  for  a  short 
distance  only,  by  placing  way-planks  and  cradle  rollers  under 
it;  if  for  a  considerable  distance,  by  backing  the  hand  sling-cart 
over  it  and  slinging  it  with  a  chain.  The  cart  is  passed  over  the 
traverse-wheels  by  raising  its  wheels  on  way-planks  placed  oa 
each  side  of  the  chassis  rails. 

In  dismounting  the  top-carriage  of  the  8-inch  rifle  (converted),, 
it  is  best  to  use  the  gin.  The  carriage  is  slung  by  the  front  and 
rear  transoms  with  chains,  the  guides  are  removed,  and  it  is 
hoisted  and  lowered  in  a  manner  similar  to  that  just  described 
for  the  gun.  The  latter  should  previously  be  removed  from  the 
platform  to  make  room  for  the  carriage  when  lowered. 

With  carriages  Nos.  1  and  2,  the  top-carriage  is  first  discon- 
nected from  the  friction-bar;  in  Nos.  3  and  4.  the  piston  of  the- 
cylinder  is  disconnected  from  the  top-carriage.  The  geared 
elevating  apparatus  should  be  removed,  or  if  not,  great  care  ex- 
ercised to  prevent  injury  to  it. 

The  chassis  and  top-carriage  of  a  barbette  gun  are  placed  in* 


252 


MACHINES  AND  APPLIANCES. 


position  on  the  platform,  and  the  piece  mounted  by  operations 
•the  reverse  of  those  just  explained.   • 

To  prevent  spreading  or  breaking,  the  hooks  of  the  gin  tackle 
should  be  securely  moused. 

Dimensions  and  weight  of  gins. 


Dimensions. 


Length  of  legs  and  pry-pole...~. 


Weights. 


Of  windlass 

Of  pry-pole 

Of  leg 

Of  gin  complete  (without  blocks) . 


Of  pulley-blocks  (iron). 


Single. 

Double 

Treble 

^Quadruple. 


Sdbgb. 


Inches. 
175.5 


Lbs. 


55 


•••  •••  ••• 


455 
43 
57 


G-ABBI802T. 


Inches. 
256.5 


Lbs. 


310 

293 

280 

1316 


165 


Cabematk. 


Inches. 
172.5 


Lbs. 


264 
208 
213 
947 


165 
205 


Remarks. 

The  garrison  gin  of  the  regulation  pattern,  if  perfectly  sound, 
is  capable  of  sustaining  a  weight  of  17,000  pounds.  It  is,  how- 
ever, recommended  that  a  heavier  one  be  used  for  such  weights 
when  it  can  be  procured. 

Use  of  the  gin  as  shears. 

500.  By  removing  the  pry-pole,  the  legs  of  the  gin  may  be 
used  as  shears.  When  the  garrison  or  casemate  gin  is  to  be  thus 
used,  a  block  of  wood  of  the  same  dimensions  as  the  head  of  the 
pry-pole,  with  a  hole  in  it  to  receive  the  clevis  bolt,  must  be 
inserted  in  place  of  the  pry-pole.  The  shears  are  raised  and 
.guyed  as  explained  in  par.  546.  The  fall  and  windlass  are 
-operated  as  for  the  gin. 

The  Garbison  Gin-derrick  (nabbow). 

{Plate  33.) 

001.  The  derrick  consists  of  two  legs  framed  together,  one 
3>ry-pole,  two  drums  or  windlasses  with  geared  wheels,  and  two 
-wagon-wheels,  serving  the  double  purpose  of  moving  the  derrick 


SLING-CARTS.  25$ 

from  point  to  point  and  for  working  the  windlass.  The  axle- 
passes  through  one  of  the  windlasses,  and  can  at  pleasure  be 
geared  into  a  wheel  on  the  other  windlass.  Length  of  legs,  264 
inches;  greatest  width  of  legs,  86  inches;  weight,  1725  pounds.. 
It  is  hoisted  by  being  pulled  over  to  the  front;  the  feet  of  the 
legs  then  rest  on  the  ground,  and  the  pry-pole  is  carried  out 
over  the  object  to  be  raised.  The  wheels  are  now  free,  and  the 
method  of  operating  the  gin  is  similar  to  that  for  other  gins,  the 
power  being  applied  to  the  wheels  instead  of  to  handspikes. 

Sling-cart. 

502.  The  sling-cart  is  used  for  moving  pieces  of  heavy  artil- 
lery, or  other  objects,  short  distances. 

They  are  of  two  kinds :  one,  the  garrison  sling-cart,  (Fig.  lr 
Plate  34,)  for  heaviest  weights,  is  attached  by  its  pole  to  a  siege 
or  field  limber,  and  may  be  drawn  by  horses;  the  other,  the 
hand  sling-cart,  (Fig.  3,  Plate  32,)  is  designed  for  moving  light- 
er weights  and  siege-pieces  in  the  trenches  by  hand.  The  siege 
limber  may  also,  in  case  of  necessity,  be  used  as  a  sling-cart. 
With  the  hand  sling-cart,  the  weight  is  raised  by  first  attaching 
to  it  a  sling,  and  then  applying  to  the  sling  the  hook  upon  the 
rear  of  the  axle,  by  raising  the  pole  of  the  cart.  The  pole  is  used 
as  a  lever,  the  axle  and  wheels  being  the  fulcrum.  It  may  be 
used  for  any  weights  not  exceeding  6000  pounds. 

With  the  garrison  sling-cart,  the  weight  is  raised  by  first  at- 
taching to  it  a  sling,  and  then  applying  to  the  sling  the  hooks 
forming  the  lower  part  of  a  powerful  screw  passing  up  through 
the  axle  of  the  cart.  Above  the  axle  is  the  nut  of  the  screw, 
provided  with  long  handles.  Power  is  applied  to  these  handles 
and  the  screw  is  run  up,  thus  raising  the  weight. 

This  sling-cart  is  capable  of  carrying  20,000  pounds ;  but  with 
such  heavy  weights  the  handles  of  the  screw  are  difficult  to  turn- 
To  overcome  this  difficulty,  a  modification  has  been  made  in  the 
cart  by  substituting  for  the  screw  a  hydraulic-jack.  (Fig.  2, 
Plate  34.) 

Through  the  axle-body  two  vertical  mortises  are  cut,  each  at 
a  distance  of  twenty  inches  from  the  middle  of  the  axle-body. 
Through  these  mortises  slide  two  stout  bars  of  iron,  with  hooks 
below  for  the  sling-chain,  and  holes  above  for  pins  to  support 
them  as  they  are  raised ;  the  pins  pass  through  the  bars  above 
the  axle-body.  A  strong  cross-bar  connects  the  upright  bars  near 
their  tops ;  under  this  the  head  of  the  jack  is  applied,  the  jack 
resting  on  the  axle-body. 


l254  MACHINES   AND   APPLIANCES. 

To  use  the  hand  sling-cart. 

503.  The  implements  necessary  are :  Two  blocks,  two  half 
-blocks,  four  wheeLchocks,  one  sling-chain,  and  one  trace-rope. 
One  sling-chain  additional  for  a  siege  mortar  mounted  on  its 
•carriage. 

To  sling  a  siege  gun,  howitzer,  or  mortar. 

The  instructor  commands : 

Back  the  cart  over  the  piece. 

Nos.  9  and  10  go  to  the  end  of  the  pole ;  INTos.  5,  6,  7,  and  8 
apply  themselves  at  the  wheels ;  the  cart  is  then  backed  over  the 
piece,  the  pole  being  in  the  direction  of  the  breech  and  the  axle 
directly  over  the  trunnions ;  Nos.  3  and  4  chock  the  wheels  front 
add  rear. 

To  sling  the  piece. 

The  gunner  fastens  the  middle  of  the  trace-rope  to  the  eye  of 
th(j  pole ;  Kos.  7  and  8  carry  one  end  of  the  rope  to  the  rear  of 
the  cart ;  Nos.  9  and  10  raise  the  pole  by  hand,  Nos.  7  and  8 
applying  themselves  at  the  same  time  to  the  rope. 

When  the  pole  is  nearly  vertical,  Nos.  9  and  10  seize  the  other 
end  of  the  trace-rope  to  steady  the  pole.  The  gunner  lays  the 
middle  of  the  sling-chain  over  the  piece  in  rear  of  the  trunnions, 
•carries  each  end  around  the  trunnions  from  the  rear  to  the  front, 
and  hooks  them  around  the  axle-hooks,  being  careful  to  take  up 
nil  the  slack ;  Nos.  9  and  10,  assisted  by  Nos.  5  and  6,  haul  upon 
the  trace-rope  until  the  end  of  the  pole  can  be  reached  by  hand, 
when  the}7  seize  and  bear  it  to  the  ground ;  Nos.  3  and  4  hook 
the  cascable-chain  around  the  knob  of  the  cascable  in  such  a 
manner  that  the  piece  will  swing  level  when  the  pole  is  hori- 
zontal; Nbs.  9  and  10  raise  the  pole  until  it  rests  on  the  pole- 
prop. 

The  piece  is  thus  raised  about  eight  inches  from  the  ground. 

For  transportation  it  should  be  ordinarily  raised  higher,  which 
•can  readily  be  done  by  blocking  up  the  piece  and  raising  it  again 
in  the  manner  above  prescribed. 

To  unsling  the  piece. 

The  piece  is  lowered  to  the  ground  in  the  same  manner,  but 
toy  inverse  means  to  those  just  prescribed. 

Nos.  9  and  10  bear  the  end  of  the  pole  to  the  ground ;  Nos.  3 
and  4  unhook  the  cascable-chain ;  Nbs.  9  and  10  allow  the  pole 
to  rise  gently  until  it  is  nearly  vertical.    If  the  piece  does  not 


SLING-CARTS.  -255 

then  rest  upon  the  ground,  it  is  blocked  up  and  inciting,  when, 
by  repeating  the  manoeuvre,  it  may  bo  lowered  to  the  ground. 

After  the  piece  has  been  unslung,  Nos.  7  aud  8  ease  the  pole 
down  carefully,  by  means  of  the  trace-rope,  until  Nos.  9  and  10 
can  reach  it  with  their  hands. 

To  sling  a  siege  mortar  mounted  on  its  carriage. 

The  instructor  gives  the  same  commands,  and  the  duties  are 
performed  by  the  same  numbers  as  prescribed  for  a  siege-piece. 

The  sling-cart  is  backed  over  the  mortar,  the  pole  being  in  the 
-direction  of  the  breech  and  the  axle  directly  over  the  trunnions. 

If  the  carriage  is  resting  on  the  ground,  it  may  be  slung  by  first 
raising  the  pole  nearly  vertical,  passing  the  sling-chain  around 
the  front  manoeuvring  bolts,  hooking  it  over  the  axle-hooks,  and 
hauling  down  the  pole. 

The  carriage  is  then  blocked  up  and  the  sling  taken  off  the 
bolts  and  passed  under  the  carriage  just  in  front  of  the  cap-square 
bolts;  this  brings  the  sling  a  little  in  front  of  the  centre  of  grav- 
ity of  the  mortar  and  carriage. 

The  pole  is  again  raised  and  the  hook  attached  to  the  sling ; 
Nos.  9  and  10  bear  down  upon  it  until  the  end  rests  upon  the 
ground ;  Nos.  3  and  4  remove  the  blocks ;  the  gunner  passes 
the  other  sling-chain  around  the  rear  maneuvering  bolts  and  over 
the  pole,  and  then  hooks  it  in  such  manner  that  the  carriage  will 
he  level;  Nos.  9  and  10  then  raise  the  pole  until  it  rests  on  the 
l>ole-prop. 

The  carriage  is  thus  raised  about  twelve  inches  from  the 
ground.  If  necessary,  it  may  be  blocked  up  and  raised  higher 
by  a  similar  manoeuvre. 

The  breech  should  always  slightly  preponderate,  in  order  to 
prevent  the  pole  from  flying  up. 

Sea-coast  mortars  and  their  beds  are  slung  separately  and 
-carried  on  the  garrison  sling-cart.  The  trunnion-chains  are 
passed  over  the  trunnions  and  hooked  to  the  hoisting  screw. 

To  transport  a  siege-piece  short  distances  with  a  limber. 

504.  The  piece  is  raised  upon  two  blocks  —  one  under  the 
breech,  the  other  under  the  chase — and  a  sling-chain  is  attached 
as  explained  in  par.  503. 

The  limber,  its  pole  being  in  the  direction  of  the  breech,  is 
run  up  until  the  pintle  is  over  the  chain,  when  the  pole  is  slightly 
raised  and  the  chain  passed  around  the  pintle  and  fastened. 
The  pole  is  borne  to  the  ground,  the  block  under  the  chase  re- 
moved, and  a  trace-rope  fastened  over  the  pole  and  around  the 


256 


MACHINES   AND  APPLIANCES. 


knob  of  the  cascable.    The  pole  is  then  raised  and  the  other 
block  removed. 

To  raise  a  piece  upon  blocks  by  a  limber. 

The  trunnion  loop,  or  an  ordinary  chain,  is  passed  over  the 
knob  of  the  cascable  and.  the  pintle,  and  made  fast  while  the 
pole  is  raised.  The  piece  is  then  raised  by  bearing  down  the 
pole,  and  the  breech  blocked  up.  The  muzzle  is  raised  in  the 
same  manner. 

The  wheels  should  not  be  chocked,  as  they  will  soon  find  their 
proper  bearing. 

To  sling  a  piece  on  two  limbers  for  transportation  with  horses* 

The  pole  of  one  of  the  limbers  is  removed,  a  block  is  placed 
under  the  body  of  the  gun,  and  the  limber  run  forward,  with  its 
fork  over  the  piece,  the  pintle  over  the  knob  of  the  cascable,  to- 
which  it  is  attached  by  a  sling-chain ;  the  fork  is  borne  down  to- 
the  piece  and  lashed  with  rope.  The  muzzle  is  then  raised  and 
supported  on  blocks ;  the  other  limber  is  backed  over  the  piece 
until  the  wheels  are  within  about  a  foot  of  the  wheels  of  the 
rear  limber ;  a  sling-chain  is  passed  under  the  piece  and  up  over 
the  pintle,  the  pole  having  been  raised  for  this  purpose ;  the  pole 
is  lowered  to  the  ground,  the  blocks  removed  from  under  the 
muzzle,  and  the  chase  lashed  to  the  forks  in  front  of  the  axle- 
tree,  so  that  the  weight  will  balance  the  pole.  To  prevent  the 
front  limber  from  pulling  away  from  the  piece,  a  sling-chain  is- 
attached  to  the  two  pintles. 


505. 


Dimensions  and  weight  of  sling-cart. 


Dimensions. 


Length  from,  rear  of  wheels  to  frcnt  end  of  pole. 

Length  of  axle-trees 

Height  of  wheels 

Distance  between  the  wheels  on  the  ground 


Weights. 


One  wheel 

Whole  weight  (without  sling-chains) 

Trunnion-chain  and  rings 

Sling -chain 


Garrison. 

Hand. 

Inches. 

242.4 
92 
96 
62.75 

Inches. 

160.75 
75.50 
72 
60.4 

Lbs. 

Lbs. 

701 

2302 
114 

84 

1115 
97 

CASEMATE   TRUCKS.  257 

The  Casemate  Truck. 
{Fig.  4,  Plate  32.) 

506.  This  machine  is  intended  for  moving  pieces  and  their 
carriages  in  the  galleries  of  casemate  batteries,  or  through  pos- 
terns. It  consists— old  pattern,  of  a  stout  frame  of  wood ;  new 
pattern,  of  wrought-iron,  mounted  on  three  low  wheels.  Two 
of  the  wheels  are  placed  at  the  sides,  like  those  of  a  cart;  the 
third  is  placed  in  a  fork  at  the  middle  of  the  front  end;  the  fork 
turns  around  its  vertical  axis  as  the  direction  of  the  truck 
changes.  The  fork  and  wheel  are  removed  by  raising  the  end 
of  the  truck  and  allowing  the  fork  to  drop  from  its  socket.  A 
tongue,  likewise  removable,  is  attached  for  the  purpose  of  guid- 
ing" the  truck. 

To  place  a  casemate  chassis  on  the  truck. 

The  chassis  is  on  the  ground,  the  truck  near  it,  with  its  front 
wheel  and  tongue  removed.  The  chassis,  either  side  down,  is 
raised,  by  successive  purchases,  with  handspikes,  and  blocked  up 
to  a  height  sufficient  to  allow  the  truck  to  go  under  it.  The 
truck  is  then  run  under  the  chassis  and  turned  so  that  its  axis 
is  parallel  to  that  of  the  chassis,  and  is  so  placed  that  the  centre 
of  gravity  of  the  chassis  is,  as  near  as  possible,  over  the  axle 
of  the  truck.  The  blocking  is  then  removed  and  the  chassis 
allowed  to  rest  on  the  truck.  The  tongue  of  the  truck  is  re- 
placed. The  truck  is  moved  to  the  designated  casemate,  and 
the  chassis  lowered  from  the  truck  as  it  was  placed  thereon. 
If  it  is  upside  down,  it  is  turned  over  as  explained  in  par.  499, 
and  placed  properly  on  the  traverse  circles.  The  tongue  of  the 
chassis  is  then  bolted  to  the  front  transom  and  secured  by  the 
pintle  in  the  throat  of  the  embrasure. 

The  chassis  may  be  lowered  from  the  truck  by  means  of  the  gin. 

To  remove  the  chassis  from  the  casemate. 

The  tongue  of  the  chassis  is  unbolted  from  the  front  transom 
and  the  chassis  raised,  either  by  prying  and  blocking  or  with  the 
gin  ;  the  truck  is  then  placed  under  it  as  before. 

It  is  generally  preferable  to  remove  the  front  wheel  from  the 
truck  and  to  pry  up  but  one  end  of  the  chassis ;  the  truck  is 
then  worked  under  it  from  the  side,  and,  after  the  chassis  is 
lowered  upon  the  truck,  the  raised  end  is  borne  down  until  the 
front  wheel  of  the  truck  can  be  replaced. 

Remark. 

To  prevent  injury  to  the  pavement,  way-planks  must  be  laid 
for  the  wheels  of  the  truck  to -run  on. 

17 


258  MACHINES    AND   APPLIANCES. 

To  place  a  top-carriage  on  the  truck. 

The  carriage  is  on  the  ground,  standing  on  the  head  of  its 
cheeks ;  the  truck  near  it,  with  its  front  wheel  and  tongue  re- 
moved. 

The  truck  is  run  up  to  the  carriage,  the  end  on  the  ground 
under  the  axle,  and  its  wheels  chocked;  the  carriage  is  then 
pulled  over  on  it  by  means  of  a  trace-rope.  The  trail  is  borne 
down  and  the  head  of  the  carriage  raised  sufficiently  high  for  the 
gunner  and  assistants  to  replace  the  truck-wheels  and  tongue. 
The  carriage  is  then  moved  on  the  truck  to  its  place. 

To  lower  the  carriage  to  the  ground. 

The  front  wheel  of  the  truck  is  removed  and  its  front  transom 
rested  on  the  ground.  The  carriage  is  then  pulled  over  on  the 
head  of  its  cheeks. 

To  shift  the  carriage  from  the  truck  to  its  chassis. 

The  truck  is  run  up  to  the  rear  of  the  chassis  rails  on  way- 
planks,  raised  on  blocks  to  a  height  sufficient  to  allow  the  car- 
riage to  be  launched  forward  upon  the  rails.  The  front  of  the 
carriage  is  towards  the  front  of  the  chassis;  the  counter-hurters 
are  removed,  and  in  launching  the  carriage  forward  it  is  so  di- 
rected that  the  guides  will  take  their  proper  places  under  the 
inner  edges  of  the  chassis  rails. 

The  carnage  may  likewise  be  put  on  the  chassis  from  the  side. 
To  do  this,  bring  it  up  on  the  truck  by  the  side  of  the  chassis,  so 
that  its  front  end  will  be  in  the  same  direction  with  that  of  the 
chassis;  remove  the  guide  from  the  cheek  farthest  from  the 
chassis  (or,  preferably,  both  guides);  pry  up  the  carriage  and 
place  under  it,  and  across  the  chassis  rails,  two  shifting-plauks ; 
heave  the  carnage  sideways  with  handspikes  until  it  is  in  proper 
position  over  the  rails;  then  remove  the  planks  and  let  the  car- 
riage rest  on  the  chassis.    Replace  the  guides. 

To  shift  the  carriage  from  its  cJiassis  to  the  truck. 

This  operation  is  similar  to  that  described  in  the  preceding 
paragraph. 

To  place  a  heavy  gun  on  the  truck. 

The  gun  is  raised,  by  means  of  a  jack,  upon  blocks  placed 
under  the  chase  and  body,  until  it  is  sufficiently  high  to  admit 
the  truck  under  it;  the  truck  is  placed  so  that  the  trunnions 
will  be  slightly  in  front  of  the  axle;  the  gun  is  then  lowered 
upon  it. 

A  gin  may  be  used  for  raising  and  placing  the  gun  on  the 


HAND-CART,  ETC.  259 

track.    The  gun  is  removed  from  the  truck  by  means  similar  to 
those  employed  for  putting  it  on. 

Remark. 

A  10-inch  gun  can  be  carried  on  the  truck  now  furnished,  but, 
except  in  very  crooked  galleries,  the  cradle  is  much  the  best 
means  for  moving  such  guns. 

Hand-cart. 

507.  This  is  used  for  the  transportation  of  light  stores  from 
one  part  of  a  work  to  another.  That  for  carrying  powder,  fuses, 
and  such  like  articles  lias  an  arched  lid-cover  to  keep  off  rain 
and  prevent  accidents  from  fire. 

Trunnion-chains. 

(Fig.  3,  Plate  34.) 

508.  The  trunnion-chains  are  three  in  number,  for  light  or 
heavyweights.  They  are  made  of  a  patent  looped-link  chain. 
A  pair  is  required  to  carry  a  gun.  One  is  passed  under  each 
trunnion  and  hooked  on  the  head  of  the  screw  of  the  sling-cart . 

No.  1,  composed  of  one  chain,  59  inches  long,  the  ends  joined 
by  a  ring;  weight,  27  pounds. 

No.  2,  composed  of  two  chains,  each  59  inches  long,  the  ends 
joined  by  a  ring;  weight,  53  pounds. 

No.  3,  composed  of  two  chains,  each  47  inches  long,  the  ends 
joined  by  a  ring  having  three  branches;  two  for  the  ends  of  the 
chains  composing  the  pair,  and  the  third  for  the  hook  of  the 
screw;  weight,  61  pounds.  Thickness  of  the  iron  composing 
the  link,  .5  inches.  Length  of  iron  for  the  connecting  ring,  23 
inches  for  No.  1 ;  24  inches  for  Nos.  2  and  3.  Size  of  iron  for 
connecting  ring,  1.375  inches,  round. 

Store-truck. 

509.  This  truck  is  used  for  moving  boxes,  Ac,  in  store- 
houses and  in  embarking  and  disembarking  stores. 

Lifting-jack. 

(Fig.  5,  Plate  32.) 

ftlO*  The  lifting-jack  is  a  geared  screw,  with  a  projecting 
foot  at  its  lower  end,  for  lifting  heavy  weights.  This  jack  is 
sometimes  to  be  found  at  military  posts,  but  is  becoming  super- 


260  MACHINES    AND   APPLIANCES. 

seded  by  the  hydraulic-jack.  The  jack  represented  in  Fig.  5  is 
the  one  carried  with  siege  guns.  It  is  very  simple,  compact, 
and  powerful. 

Lever-jack. 

511.  The  lever-jack  is  an  adjustable  fulcrum  with  a  long 
lever,  used  chiefly  for  greasing  the  axles  of  traveling  carriages. 

Hand-barrow. 

5 12.  Wood ;  two  side  rails;  the  ends  are  rounded  and  form 
handles.  Rope  netting  joins  the  side  rails,  passing  through  holes 
in  the  side  rails. 

Maul. 

513.  This  is  used  for  driving  stakes,  and  such  like  purposes. 
That  furnished  from  arsenals  has  a  cylindrical  head  of  wood,  6 
inches  in  diameter  and  8  inches  long,  with  an  iron  band  around 
each  end.  The  handle  is  24  inches  long  and  1.5  inch  in  diameter. 
Weight,  10  lbs.  This  maul,  as  issued,  owing  to  poor  material 
and  faulty  construction,  is  of  but  little  value.  Where  much  ser- 
vice is  required,  it  is  better  to  make  the  head  of  tough,  hard 
wood,  with  a  handle  considerably  larger  than  the  one  of  regula- 
tion pattern. 

Truck-wagon. 

{Plate  35.) 

514.  This  is  a  powerfully-constructed  four-wheel  wagon,  in- 
tended for  the  transportation  of  iron  gun  carriages,  sea-coast 
mortars  and  their  carriages,  and  other  similar  heavy  weights. 
The  wheels  have  a  diameter  of  42  inches;  the  axles  are  of  iron 
and  the  bolsters  of  heavy  pieces  of  timber,  having  their  upper 
surfaces  flush  with  the  tops  of  the  wheels.  Heavy  plates  of  iron 
cover  the  tops  of  the  bolsters  and  project  slightly  over  the  wheels. 
The  ends  of  these  plates  are  turned  up,  forming  a  projection 
about  two  inches  high,  to  prevent  the  body  transported  from 
slipping  off  sideways.  The  width  between  these  projections  is 
just  sufficient  to  admit  the  chassis  of  the  15-inch  gun. 

The  wagon  is  capable  of  being  coupled  long  or  short,  to  suit 
the  length  of  the  object  to  be  transported.  The  pole,  like  that 
of  an  ordinary  road-wagon,  is  furnished  with  double-trees  for 
attaching  horses. 


MORTAR-WAGON,  ETC.  261 

The  method  of  using  this  wagon  in  the  transportation  of  the 
15-inch  carriage  and  chassis,  is  explained  in  par.  636,  and  for 
transporting  the  13-inch  mortar,  in  par,  537. 

When  a  13-inch  mortar  without  its  bed  is  to  be  carried,  two 
8 tout  skids,  about  12  feet  long  and  12  by  12  inches  thick,  are 
placed  on  tiie  wagon.  The  skids  are  notched  to  tit  the  bolsters, 
to  prevent  them  from  sliding  to  the  front  or  rear,  and  a  shallow 
recess  is  cut  in  them  to  form  a  seat  for  the  mortar.  The  mortar 
is  placed  on  the  skids  with  its  axis  parallel  to  the  axis  of  the 
wagon ;  it  is  hoisted  into  this  postition  by  means  of  the  gun-lift 
or  the  gin. 

MORTAR-WAGON. 

(Plate  36.) 

515.  This  wagon  is  used  for  the  transportation  of  siege  mor- 
tars, siege  guns,  and  heavy  projectiles.  The  limber  and  wheels 
are  the  same  as  those  for  the  siege-gun  carriage.  The  body  con- 
sists of  a  platform  of  rails  and  transoms,  resting  on  the  rear  axle- 
tree,  the  two  middle  rails  being  prolonged  to  the  front  to  form 
the  stock.  The  side  rails  are  prolonged  to  the  rear,  and  furnish 
supports  for  the  roller  of  a  windlass,  which  is  used  for  loading 
the  wagon,  the  guns,  mortars,  &c,  being  drawn  up  the  stock, 
which  rests  on  the  ground,  forming  an  inclined  plane.  Each 
end  of  the  roller  is  provided  with  pawl  and  ratchet,  operated  by 
a  handspike,  fitting  into  a  socket  after  the  manner  of  the  wind- 
lass of  a  giu. 

Over  good  and  firm  roads  the  mortar-wagon  is  capable  of  car- 
rying the  100-pounder  Parrott,  or  any  other  piece  not  exceeding 
in  weight  10,000  pounds. 

The  Cradle. 

(Plate  37.) 

516.  This  is  a  machine  used  for  transporting  heavy  guns 
short  distances.  It  is  made  of  oak,  and  consists  essentially  of 
two  parallel  rails  13  feet  6  inches  long  and  10  by  12  inches  thick. 
These  rails  are  united  by  a  transom  near  each  end  and  one  in 
the  middle ;  these  transoms  have  such  length  as  to  make  the 
entire  width  of  the  cradle  60  iuches.  A  bolster  is  placed  over 
each  end  transom  ;  the  ends  of  these  bolsters  are  flush  with  the 
exterior  sides  of  the  rails.  The  bolsters  for  the  support  of  the 
breech  are  6  inches  high  and  8  inches  thick;  that  for  the  chase 
15  inches  high  and  6  inches  thick;  the  middle  part  of  the  top 


262  MACHINES   AND   APPLIANCES. 

of  each  is  slightly  hollowed  out  to  form  seats  for  the  piece.  A 
movable  bolster,  having  notches  at  each  end  to  lit  upon  the  rails, 
is  intended  to  be  placed  tight  up  against  the  middle  part  of  the 
gun  after  it  has  been  placed  on  the  cradle. 

Diagonal  braces  are  fitted  inside  between  the  rails  and  tran- 
soms. The  under  part  of  the  ends  of  the  rails,  both  front  and 
rear,  are  beveled  off,  so  that,  in  moving  hi  either  direction,  the 
rollers  can  be  caught  under  the  cradle  with  facility.  The  under 
surfaces  of  the  rails  are  shod  with  iron  to  prevent  them  from 
splintering  out.  A  ring  is  attached  by  a  link  and  eye-bolt  to 
each  end  transom  for  the  purpose  of  attaching  blocks  and  tackle 
when  moving  the  cradle  and  piece. 

The  cradle  moves  on  wooden  rollers ;  each  roller  is  78  inches 
long  and  7  inches  in  diameter.  From  six  to  ten  rollers  are  re- 
quired ;  they  rest  and  move  on  way-planks  laid  on  the  ground. 

The  method  of  using  the  cradle  is  explained  in  par.  535. 

The  Capstan. 

(Fig.  1,  Plate  38.) 

51*7.  This  machine  is  used  as  a  strong  purchase  in  heaving 
or  hoisting.  When  so  employed,  it  is  held  in  position  by  stout 
chains  attached  to  holdfasts.  The  rope  is  passed  two  or  three 
times  around  the  barrel  of  the  capstan,  the  free  end  coming  off 
above  the  turns ;  the  standing  part  is  attached  to  the  weight  to 
be  moved.  The  rope  is  drawn  taut  by  hand,  the  bars  inserted 
into  the  mortises,  and  the  free  end  of  the  rope  held  and  taken 
in  by  two  men  seated  on  the  ground. 

Twelve  men — three  at  each  bar — are  all  that  can  be  advan- 
tageously employed.  When  additional  power  is  required,  the 
bars  are  swifted  ;  that  is,  the  ends  of  the  bars  are  lashed  together 
with  ropes,  by  which  additional  men  to  take  hold. 

The  method  of  using  the  capstan  in  hoisting  a  15-inch  gun  by 
means  of  the  derrick,  is  explained  in  par.  549,  and  for  moving 
it  on  the  cradle  up  or  down  a  ramp,  in  par.  535. 

Gin  as  a  Capstan. 

518.  Put  the  gin  together  on  the  ground  in  the  usual  man- 
ner; place  the  feet  of  the  legs  toward  the  weight,  and  secure 
them  well  with  stakes  against  the  cro-s-bars,  feet,  and  head  of 
the  gin  ;  rig  the  fall  as  usual,  and  attach  the  hook  of  the  lower 
block  to  a  rope  of  suitable  strength  running  to  the  weight  to  be 
moved;  the  windlass  is  worked  in  the  same  manner  as  when 


HOLDFASTS.  2()3 

the  gin  is  standing.  Or  the  gin,  wirh  its  pry-pole  in  the  direc- 
tion  of  the  weight  to  be  moved,  may  be  raised  almost  to  its  usual 
position  for  hoisting.  A  block  is  hooked  to  the  clevis,  and  through 
it  the  rope  is  passed  from  the  weight  to  the  windlass ;  the  latter 
is  worked  as  usual. 

Holdfasts. 

519.  Pickets.  These  are  stout  wooden  stakes  to  be  driven 
into  the  ground,  and  used  for  securing  purposes  and  in  the  con- 
struction of  holdfasts.  The  ordinary  stakes  for  siege-gun  plat- 
forms answer  for  most  cases.  When  very  heavy  strains  are  to 
be  borne,  posts  from  five  to  eight  feet  long  are  required,  and 
are  set  into  the  ground  by  digging  holes,  or  with  a  pile-driver. 
When  the  latter  is  used,  the  post  should  be  shod  wirh  an  iron 
point,  and  have  a  ring  upon  the  head  to  prevent  splitting. 

$20.  Pile-driver.  A  good  form  for  this  is  an  iron  tube  (Fir/. 
2,  Plate  38)  about  ten  feet  long,  with  a  calibre  of  about  five 
inches.  One  end  of  the  tube  is  set  into  a  broad  block  of  wood, 
forming  a  base.  Upon  each  side  of  the  top  is  attached  a  sheave, 
over  which  works  a  rope ;  these  ropes  are  attached  to  the  ham- 
mer, and  are  hauled  on  by  hand  until  the  hammer  is  at  the 
top  of  the  tube,  when  they  are  suddenly  let  go  and  the  hammer 
allowed  to  drop  upon  the  head  of  the  pile.  The  hammer  is  an 
elongated  bolt  of  iron,  weighing  from  fifty  to  eighty  pounds,  and 
of  a  diameter  to  work  freely  in  the  tube. 

To  use  the  pile-driver,  it  is  laid  on  the  ground  and  the  pile  or 
stake  introduced,  head  foremost,  into  the  tube.  The  machine  is 
then  set  up  over  the  point  where  the  pile  is  to  be  driven,  held 
steady,  and  the  ropes  worked  as  just  explained. 

In  the  absence  of  an  iron  tube,  a  box  of  hard  wood  may  be 
need  in  its  stead. 

To  draw  heavy  pickets,  a  gin,  a  sling-cart,  or  a  limber  may  be 
uied.  They  may  also  be  drawn  by  the  application  of  a  lever, 
tbe  point  being  passed  through  a  rope  or  chain  around  the  picket. 

In  drawing  pickets,  care  should  be  taken  that  they  are  drawn 
oit  in  the  same  line  as  that  in  which  they  were  driven. 

521*  The  most  essential  points  to  be  considered  before  any 
heavy  weight  is  moved  or  suspended,  are  the  nature  and  condi- 
tion of  the  securing  points,  together  with  the  strain  that  will  be 
brought  on  them.  Natural  holdfasts — such  as  the  piers  of  case- 
antes,  pintles  for  guns  of  position,  trees,  <fcc. — may  frequently 
be  found,  around  which  straps  may  be  placed.  In  such  cases  all 
cornel's  should  be  protected  by  wood,  or  the  rope  itself  parceled 
to  prevent  chafing. 


264  MACHINES   AND    APPLIANCES. 

In  places  where  holdfasts  can  be  driven  or  sunk,  the  ordinary 
picket  post  can  be  made  use  of,  but  only  when  light  weights 
have  to  be  dealt  with. 

In  securing  to  a  holdfast  from  which  it  may  become  necessary 
to  ease  off,  at  least  one  complete  turn  must  be  taken  before  mak- 
ing fast ;  otherwise,  when  the  strain  is  on  it,  it  is  difficult  to  cast 
off. 

Precise  rules  cannot  be  laid  down  as  to  the  description  of  hold- 
fast best  suited  for  particular  operations,  but  it  should  be  borne 
in  mind  that  it  will  save  much  time  and  trouble  to  make  h  in 
the  first  instance  considerably  more  secure  than  seems  to  be  ab- 
solutely necessary,  as  when  a  holdfast  once  begins  to  give,  it  is 
difficult  to  strengthen  it.  Whatever  holdfast  may  be  used,  tfie 
strain  should  be  laken  by  the  entire  structure  at  once;  otherwise 
it  might  give  way  in  del  ail  when  it  would  not  do  so  as  a  whole. 

Figs.  1,  2,  3,  4,  5,  Plate  39,  represent  some  of  the  methods  of 
constructing  holdfasts. 

When  the  strain  to  be  sustained  is  very  great,  the  one  shovn 
in  Fig.  5  is  used ;  a,  6,  c,  d  is  a  trench  from  ten  to  fifteen  fe«t 
long  and  two  to  four  feet  in  width  and  depth.     It  is  dug  in  a 
direction  perpendicular  to  the  strain.     Several  heavy  stakes  aie 
driven  in  the  trench  far  enough  from  the  side  to  admit  planks 
being  placed  between  them  and  the  earth.     A  heavy  beam,  witn 
the  bight  of  a  chain  around  it,  is  then  laid  on  the  bottom  of  the 
trench  against  the  stakes,  the  ends  of  the  chain  being  brought 
up  between  the  planks  along  a  trench,  rising  gradually  to  the 
surface  so  that  there  will  be  no  tendency  to  lift  the  beam  up 
when  the  strain  is  on  it.     The  whole  trench  is  then  filled  in  and 
rammed. 

Anchors  or  Ijeavy  cannon  may  be  buried  and  used  as  hold- 
fasts. 

Hydraulic-jack. 

(Figs.  1  to  12,  Plates  40,  41.) 

522.  Owing  to  their  efficiency  and  simplicity,  these  hand; 
and  powerful  machines  are  much  used  wherever  ponderoui 
weights  are  to  be  moved,  and  are  an  invaluable  recourse  for 
artillery  purposes  of  this  nature. 

Fig.  1  shows  the  constructive  points  of  one  form  of  the  jacH 
whereof  Fig.  2  is  a  general  view.  When  the  jack  is  depressec, 
its  external  appearance  is  that  of  a  cylinder  or  pillar,  but  whife 
being  elevated  it  seems  only  one  cylinder  sliding  outside  anothei 
The  outer  cylinder  (a)  is,  however,  simply  a  tube  affixed  to  th» 
head  as  a  ground  attachment,  and  carries  a  claw  (g)  to  suppor. 


HYDKAULIOJACK.  265 

the  weight  to  be  raised ;  the  head  (h)  is  also  applicable  to  this 
purpose.  The  inner  cylinder  (6)  is  the  true  cylinder,  within 
which  again  is  another  or  inmost  cylinder  (c),  which  is  the  true 
ram.  This  last  cylinder  is  hollow,  and  iu  the  enlarged  head  car- 
ries the  pivot  (p)  of  the  socket  (s)  and  lever-arm  (7),  whereby  the 
force  pump  is  worked.  The  internal  capacity  of  the  mm  and 
head  is  the  equivalent  of  the  fluid  contents  of  the  cylinder  (6) 
when  the  ram  is  raised;  it  is,  therefore,  in  fact  the  reservoir  or 
source  of  the  hydraulic  power.  Fitting  nicely  into  the  lower 
part  of  the  hollow  of  the  ram  is  the  piston-head  with  a  suitable 
valve,  and  a  similar  valve — both  of  which  will  be  given  in  detail 
further  on — is  fitted  below  it  into  the  bottom  of  the  ram.  The 
necessarj'  reciprocating  motion  is  communicated  to  the  piston- 
head  by  a  piston-rod  (e)  passing  within  the  ram,  suitably  con- 
nected with  and  moved  by  the  lever  handle.  There  are  three 
leather  packings :  one  (d)  to  the  ram  in  the  cylinder  (c),  one  to 
the  piston-head,  and  one  to  the  pivot  of  the  lever.  By  the  action 
of  the  lever-arm  the  fluid  is  forced  into  the  cylinder  (b)  beneath 
the  ram,  and  simultaneously  the  ram  and  its  load  are  raised. 
When  the  jack  is  lowered,  the  fluid  simply  passes  back  into  the 
ram  and  head. 

Fig.  3  is  another  form,  having  a  broad  base ;  it  is  the  same  in 
principle  as  Fig.  1,  but  does  not  carry  the  outer  cylinder  and 
claw. 

The  larger  jacks,  and  in  fact  those  most  used  for  artillery,  are 
shown  in  Figs.  4,  5,  6,  and  7,  which  give  the  details  of  construc- 
tion, of  which  Fig.  8  is  a  general  view.  This  jack  di tiers  some- 
what from  those  mentioned,  in  that  the  ram  (a)  is  a  solid  plunger, 
sliding  in  a  simple  cylinder  (6),  which  is  fixed  to  the  base  of  the 
cast-iron  reservoir  (k).  The  force  pump  is  contained  in  a  simi- 
lar cylinder  (c),  and  the  two  are  connected  through  their  lower 
extremities  by  a  channel  not  more  than  one-eighth  of  an  inch  in 
diameter,  contained  in  the  reservoir  base.  The  course  of  this 
channel  is  shown  in  Figs.  6  and  7,  which  are  views  of  the  base, 
into  which  is  let  a  movable  brass  stopper  (d),  which  is  the  bot- 
tom of  the  channel  and  allows  access  to  it.  Screwed  into  the 
top  of  the  reservoir,  and  directly  above  the  force-pump  cylinder, 
is  a  cap  (e)  carrying  a  ring  encircling  the  ram,  serving  as  a  han- 
dle for  moving  and  carrying  the  jack.  This  cap  receives  the  pis- 
ton-rod (f)  and  holds  it  iu  a  vertical  position,  maintaining  its 
connection  with  the  spindle  (<jr),  from  which  a  tongue  (i)  enters 
the  square  eye  (h)  formed  in  the  rod  to  receive  it.  The  spindle 
is  suitably  connected  with  the  socket  and  lever-arm,  from  which 
it  receives  motion  and  actuates  the  piston  pump,  whereby  the 
fluid  is  forced  through  the  pump  and  channel  into  the  cylinder 


266  MACHINES   AND   APPLIANCES. 

and  beneath  the  ram,  thus  raising  the  load.  When  the  ram  is 
lowered,  the  fluid  passes  back  into  the  reservoir  through  the 
same  connections.  There  are  three  packings,  viz. :  one  to  the 
lower  end  of  the  piston-rod,  one  to  the  ram,  and  one  to  the  spin- 
dle. The  ram  carries  a  movable  claw  as  a  ground  attachment, 
(a,  Fig.  8.) 

The  valves.  The  valves  of  the  larger  jack  and  their  various 
functions  and  constructive  details  are  shown  in  Figs.  9,  10,  and 
11.  The  piston-rod  (f)  differs  from  that  of  other  forms  already 
mentioned  by  its  lower  half  being  hollow,  to  admit  of  its  cann- 
ing a  small  steel  rod  (r),  which  backs  up  the  valve-plunger  (p), 
and  by  having  cut  in  its  exterior  surface  two  channels  (a:)  in  the 
same  plane  containing  the  square  eye,  and  converging  at  the 
lower  extremity.  These  channels  admit  the  passage  of  the  fluid 
into  the  pump-cylinder,  which  is  usually  submerged  in  the  fluid 
during  the  ascent  of  the  piston-rod.  The  upper  valve  is  simply  a 
plunger  and  cap  (v)  of  brass;  the  latter  is  bored  with  three  holes 
for  the  fluid,  and  is  screwed  into  the  bottom  of  the  piston-rod ; 
the  former  is  solid,  and  has  a  slight  play  in  the  space  formed  by 
the  convergence  of  the  two  channels  and  the  brass  cap.  At  the 
upward  stroke  this  valve  is  open  from  the  pressure  of  the  fluid 
passing  the  channels,  the  plunger  resting  in  the  cap.  At  the 
downward  stroke  it  is  closed^  the  plunger  stopping  the  channels 
at  tlieir  convergence  from  the  fluid  pressure  below.  The  lower 
valve  is  simply  a  plunger  (z)  of  brass  working  in  a  chamber  at 
the  bottom  of  the  pump-cylinder,  and  rests  on  a  spiral  spring  (s), 
which  is  fixed  to  a  screw  passing  through  the  base  of  the  jack 
from  the  outside.  At  the  upward  stroke  this  valve  is  closed  by 
the  spring;  at  the  downward  it  is  opened  by  the  pressure  of  the 
fluid,  but  closes^  by  the  action  of  the  spring,  immediately  upon 
a  cessation  of  this  pressure.  It  admits  the  passage  of  the  fluid 
into  the  channel  (w)  connecting  the  ram-cylinder,  thence  under 
the  ram. 

A  stop  on  the  under  side  of  the  lever  handle  near  the  socket 
prevents  the  two  valves  from  meeting  at  the  downward  stroke ; 
by  reversing  this  stop  and  pressing  the  handle  downward  gently 
the  cap  of  the  upper  is  brought  in  contact  with  the  plnnger  of 
the  lower  valve,  which  it  opens  to  an  extent  according  to  the 
stroke ;  the  fluid  immediately  passes  through,  opening  the  upper 
valve,  and  the  ram  descends  proportionally.  This  is  called  trip- 
ping. A  cessation  of  the  pressure  upon  the  handle  arrests  all 
motion. 

The  valves  of  the  other  forms  are  essentially  on  the  same  prin- 
ciple, the  chief  difference  being  that  the  lower  valve  is  screwed 


HYDRAULIC-JACK.  267 

into  the  bottom  of  the  hollow  ram,  while  the  upper  works  in  the* 
piston-head. 

Thus  it  is  seen  that  one,  and  only  one,  pair  of  valves  is  effective 
in  the  various  functions,  viz.,  to  raise,  lower,  and  stop  at  an}' 
given  point,  and  to  miss  a  stroke  if  required ;  these  different 
effects  being  simply  realized  by  a  mere  reversal  of  the  lever  han- 
dle in  its  socket.  In  all  other  respects  the  sole  secret  involved 
is  good  work  and  fitting  and  proper  adaptation  of  wearing  sin- 
faces  by  case-hardening  metal,  with  care  in  an  occasional  renewal 
of  the  leather  packing. 

These  jacks  are  made  in  sizes  to  rise,  varying  from  7  inches  to- 
2  feet,  to  lift  or  press  from  4  to  120  tons,  and  from  2  inches  and 
upwards  iu  diameter,  according  to  power.  The  form  first  men- 
tioned is  usually  employed  standing  or  obliquely ;  the  last  named 
may  be  used  in  any  position.  They  may  be  worked  by  one  man 
only,  being  thus  capable  of  raising  10  tons  one  foot  in  one  and  a 
half  minutes,  or  in  that  proportion. 

Fig,  12  is  a  hydraulic  pulling-jack  applicable  for  setting  up- 
rigging,  testing  chains  and  rope,  pile-drawing,  slinging  heavy 
weights  in  couflned  spaces,  <fcc.  It  differs  from  the  lifting-jack 
in  being  extended  when  commencing  to  work,  and  then  being 
contracted  by  fluid  force. 

To  fill  the  lifting-jack. 

523.  Remove  the  small  screw  in  the  head,  having  the  piston, 
or  ram  quite  down ;  fill  the  jack  through  the  screw  hole  in  the 
head  with  winter-strained  sperm  oil,  alcohol,  or  whiskey,  adding 
to  the  latter  (if  liable  to  freeze)  a  table3poonful  of  sperm  oil; 
work  the  lever  while  pouring  in  the  liquid  until  the  ram  or  piston 
is  up  to  its  full  stroke ;  when  this  occurs  the  jack  is  sufficiently 
full.  Then  reverse  the  lever  and  push  the  ram  or  piston  back 
to  the  bottom  of  the  cylinder,  and  replace  the  screw  in  the  screw 
hole  in  the  head  of  the  jack.  This  screw  is  not  intended  to  fit 
tightly,  and  must  not  be  screwed  tight  home  after  filling.  Be 
careful  that  no  dirt  gets  into  the  head  of  the  jack  while  filling. 

The  liquid  may  consist  of  equal  parts  of  alcohol  and  water,  or 
equal  parts  of  whiskey  and  water;  but  these  liquids  should  not 
be  used  when  the  temperature  is  at,  or  likely  to  be  at,  freezing 
point.  Neither  kerosene  oil  nor  spirits  of  turpentine,  nor  any 
other  liquid  liable  to  corrode  the  packing,  is  suitable  for  use  in  the 
jack. 

To  fill  the  hydraulic  pulling-jack. 

524*  With  the  iron  key  unscrew  and  remove  the  screw  at 
each  end  of  the  cylinder;  if  the  piston  is  not  down,  push  it  home ;. 


268  MACHINES   AND    APPLIANCES. 

flli  through  the  two  screw  holes  with  the  same  liquid  as  is  used 
in  the  lifting-jack,  and  replace  the  screws,  screwing  them  home, 
but  not  too  tight. 

To  use  the  lifting-jack. 

525.  To  lift.  Place  the  head  of  the  jack  under  the  object 
to  be  lifted.  If  the  object  is  too  near  the  ground  to  admit  of 
this,  use  the  iron  claw,  placing  oue  of  its  hooks  under  the  object 
and  the  other  (which  has  a  dowel)  over  the  head  of  the  jack.  In- 
sert that  end  of  the  lever  which  is  squared  (or  made  with  a  jour- 
nal) and  has  a  projecting  shoulder  into  the  mortise  or  slot  of 
the  jack,  the  projection  of  the  shoulder  downward  (or  under- 
neath), and  pump  until  the  object  is  raised  to  the  required 
height.  If  this  height  is  greater  than  the  full  stroke  of  the  pis- 
ton or  ram,  block  up  the  object  lifted,  reverse  the  lever  so  that 
the  projection  of  the  shoulder  is  upward  (or  above),  press  upon 
it  until  it  is  at  the  bottom  of  its  stroke,  and  then  push  the  piston 
or  ram  down  to  the  bottom  of  the  cylinder;  block  the  jack  up 
higher ;  then  reverse  the  lever,  and  proceed  to  raise  the  object 
as  in  the  first  instance. 

It  sometimes  happens  that  the  piston  or  ram  cannot  be  pushed 
down  after  it  has  been  run  up  to  its  full  height  or  stroke.  This 
difficulty  can  be  overcome  by  slacking,  with  a  few  turns,  the 
small  screw  in  the  head  of  the  jack,  and  thus  allowing  the  air 
with  which  the  jack  is  tilled  to  escape. 

Sometimes  the  jack  fails  to  work  in  consequence  of  the  valve 
sticking  in  its  seat.  This  difficulty  can  be  overcome  D37"  striking 
the  lever  a  few  sharp  blows  up  and  down  with  a  wooden  mallet 
or  stick,  which  will  jar  the  valve  and  cause  it  to  resume  its 
action. 

The  lifting-jack  can  be  used  standing  at  any  angle  between  10 
and  90  degrees  above  the  horizontal ;  but  great  care  must,  at  all 
times,  be  exercised  that  the  support  for  its  base  is  secure,  and  that 
its  head  is  not  permitted  to  slip  from  under  the  object  to  be  raised. 

526.  To  lower.  Place  the  head  of  the  jack  securely  under 
the  object  to  be  lowered,  with  the  piston  or  ram  run  up  to  the 
distance  to  which  the  object  is  required  to  be  lowered;  pump 
until  the  object  is  raised  sufficiently  to  remove  the  supports  from 
under  it ;  take  out  the  lever,  and  reverse  it  so  that  when  put  back 
in  the  slot  or  mortise  the  projection  of  the  shoulder  of  the  lever 
is  upward  (or  above);  then,  with  a  slight  pressure  of  the  hand, 
push  the  lever  downward  as  far  as  it  will  go,  when  the  piston 
will  commence  to  descend,  and  will  continue  to  lower  as  slowly 
as  desired.  By  raising  the  lever  slightly,  the  lowering  can  be 
arrested  at  any  point.    The  object  must  not  be  lowered  too  fast, 


HYDRAULIC-JACK. 


269 


nor  the  lowering  checked  too  suddenly,  or  the  jack  will  cease  to 
work. 

To  use  the  pulling-jack. 

527.  Screw  on<»  end  of  the  jack  to  some  fixed  object  (the  end 
nearest  the  pump  is  preferable);  unscrew  the  valve  in  the  pump 
by  two  or  three  turns  with  the  key,  and  stretch  the  jack  apart ; 
attach  the  free  end  of  it  to  the  object  to  be  movtMl ;  shut  the 
valve  by  screwing  back  the  two  or  three  turns  that  were  un- 
screwed ;  attach  the  long  lever  and  pump  away  at  it  until  the 
object  is  moved  as  desired.  When  there  is  not  room  for  the  long 
lever,  the  pump  can  be  worked  by  the  short  lever.  If  the  jack 
does  not  start  at  once,  slack  the  screw  in  the  cylinder  close  to 
the  pump  (which  the  same  key  fits)  until  a  drop  or  two  of  the 
fluid  comes  out ;  as  soon  as  this  occurs,  turn  the  screw  imme- 
diately back.  If  the  piston  or  ram  will  not  run  out  to  its  entire 
length  or  stroke,  place  the  jack  in  a  horizontal  position,  take  out 
the  screw  at  each  end  of  the  cylinder,  and  fill  through  both  holes 
with  the  usual  liquid. 

The  pulling-jack  can  be  used  to  pull  or  lift  at  any  angle  be- 
tween the  horizontal  and  the  perpendicular,  but  the  direction 
of  its  force  must  be  in  a  straight  line,  and  the  force  pump  always 
at  the  lowest  end  when  the  jack  is  used  in  any  other  way  than  hor- 
izontal^. When  the  pulling-jack  is  in  use,  the  lever  joints  must 
be  well  oiled  and  kept  free  from  dirt;  when  not  in  use,  the 
piston-rod  must  be  kept  in ;  and  when  hung  up,  the  end  where 
the  pump  is  must  always  be  downward. 

STo  greater  force  than  that  of  one  man  (provided  he  applies  a 
power  of  about  150  pounds)  need  ever  be  applied  to  the  lever 
of  either  the  lifting  or  the  pulling  jack,  since  that  force  is  amply 
sufficient  to  work  the  jack  to  its  full  capacity. 

The  hydraulic-jacks  usually  employed  for  artillery  purposes- 
have  15-ton  or  30-ton  lifting  capacity. 

Weight  and  dimensions  of  hydraulic-jacks. 


Kind  of  Jack. 

Height. 

Height 

op 
Lift. 

Weight 

(filled). 

Weight 

of 
Olaw. 

Inches. 

20 
62 
20 

Inches. 

12 
18 
12 

Pounds. 

230 
310 
140 

Pounds. 
90 

••• 

SO 

270  machines  and  appliances. 

Blocks  and  Skids. 

528.  Blocks  are  rectangular  prisms  of  wood  employed  ex- 
tensively in  all  operations  connected  with  the  movements  of 
heavy  artillery.  Skids  are  rectangular  beams  of  wood  used  for 
similar  purposes.  The  dimensions  of  those  used  in  the  lighter 
mechanical  manoeuvres  are  given  in  par.  416;  those  for  heavier 
operations,  in  par.  534. 

All  blocks  and  skids  should  be  sound,  free  from  knots,  and 
perfectly  true  in  dimensions.  When  the  edges  become  splintered 
aiid  rounded  by  wear,  they  should  be  discarded,  as  with  such  it 
is  impossible  to  erect  safe  and  stable  scaffolding  and  supports. 
They  should  not  be  painted ;  the  thickness  of  each  should  be 
marked  upon  both  ends.  In  erecting  a  scaffold  or  other  sup- 
port, a  level  foundation  is  of  the  first  consideration ;  the  blocks 
should  then  be  laid  crossing  each  other  in  alternate  tiers,  and  the 
weight  supported  should  be  made  to  bear  equally  upon  all  sides 
of  the  base. 

529.  The  way-plank  is  an  oak  plank  15  feet  long,  12  inches 
wide,  and  3  inches  thick.  Each  end  is  beveled  for  a  distance  of 
six  inches,  the  bevel  on  one  end  being  on  the  side  opposite  the 
bevel  of  the  other  end.  These  planks  are  used  chiefly  for  form- 
ing temporary  tramways  for  roller,  or  for  the  wheels  of  car- 
riages bearing  heavy  weights. 

530.  The  pinch-bar  {Fig.  3,  Plate  38)  is  simply  a  stout  hand- 
spike, of  iron,  with  a  round-beveled  butt,  turned  up  into  a  blunt 
<*dge  for  the  purpose  of  catching  under  a  gun  or  other  similar 
object.  It  is  used  as  a  lever,  by  pressing  down,  thus  jumping 
the  gun  forward  a  very  short  distance  at  a  time.  The  butt 
cud  is  of  steel.  The  length  of  the  bar  is  from  five  to  seven  feet. 
Those  used  with  the  15-inch  gun  are  of  the  largest  size,  and 
weigh  53  pounds;  the  shorter  size  weigh  26  pounds. 

531.  The  collar  (Fig.  4,  Plate  38)  is  a  device  placed  upon 
the  chase  of  a  gun  to  make  its  diameter  equal  to  that  of  the 
body  of  the  piece.  This  enables  the  gun  to  be  rolled  with  facil- 
ity. It  is  made  of  pieces  of  scantling  jointed  together  after  the 
manner  of  the  staves  of  a  cask,  and  hooped  with  stout  bands  of 
iron.  It  is  shoved  over  the  muzzle  onto  the  chase,  and  secured 
with  wedges  of  wood. 

532.  Chocks  (Fig.  11,  Plate  18)  for  the  15-inch  gun  are  made 
of  solid  oak  wood,  of  the  shape  and  dimensions  represented  in 
the  figure.  The  grain  of  the  wood  runs  lengthwise  with  the 
chock. 

When  the  piece  is  to  be  slued,  a  chock  is  used  having  the  bev- 
eled side  cut  out  slightly  concave ;  the  opposite,  or  fiat  side,  is 


FLANK-CASEMATE   HOWITZER.  271 

shod  with  spikes,  for  the  purpose  of  keeping  it  from  slipping. 
The  concave  side  is  placed  against  the  piece,  and  well  greased, 
to  allow  the  piece  to  turn  easily  upon  it. 

to  mount   and  dismount   the  flank  -  casemate 

Howitzer. 

The  implements  necessary  are:  One  half  roller,  two  half 
blocks,  two  skids,  four  blocks,  four  gun-chocks,  one  hammer- 
wrench. 

The  piece  being  from  battery. 

533*  The  instructor  commands : 

1.  Dismount  the  carriage. 

Nos.  1,  2,  and  the  gunner  remove  the  pintle  and  run  the  car- 
riage into  battery;  the  gunner,  assisted  by  Nos.  3  and  4,  takes 
off  the  three  nuts  that  hold  the  fork  ;  a  handspike,  manned  by 
Nos.  1,  2,  5,  and  6,  is  passed  under  the  chassis  immediately  in 
rear  of  the  fork,  and  at  the  command  Heave  from  the  gunner, 
the  chassis  is  raised,  the  fork  removed,  and  the  trail  carefully 
lowered  to  the  ground;  Nos.  3,  4,  5,  and  6  then  lay  the  skids  in 
rear  and  in  prolongation  of  the  chassis,  their  outer  edge*  in  line 
with  those  of  the  chassis;  Nos.  1,  2,  and  the  gunner  then  run 
back  the  carriage,  applying  themselves  as  in  from  battery,  until 
the  rear  end  of  the  cheeks  touch  the  counter-hurters. 

The  gunner  bears  down  on  the  roller  handspike  to  raise  the 
trail  as  much  as  possible,  and,  assisted  by  Nos.  3  and  4,  who 
place  the  ends  of  their  handspikes  under  the  outer  edges  of  the 
trail,  lifts  it  over  the  counter-hurters  onto  the  skids. 

When  the  front  rollers  touch  the  counter-hurters,  No.  2  puts 
his  handspike  into  the  bore  and  chocks  it;  Nos.  1  and  2,  assisted 
by  No.  5,  raise  the  muzzle ;  Nos.  3  and  4  lift  at  the  manoeuvering 
rings,  and  run  back  the  carriage  until  the  front  rollers  rest  on 
the  skids;  Nos.  1,  2,  3,  4,  and  the  gunner  (the  latter  embarring 
in  the  left  mortise,  and  pressing  the  roller  under  the  rear  tran- 
som, and  Nos.  1,  2,  3,  and  4  laying  hold  of  the  manoeuvering 
rings  and  handles)  run  the  carriage  back  on  the  skids  until  the 
muzzle  is  over  their  front  ends. 

The  instructor  commands : 

1.  Dismount  the  howitzer. 

Nos.  3  and  4  remove  the  cap-squares,  and  lay  a  block  and  a 
half  block  across  the  skids,  touching  the  head  of  the  cheeks;  No. 
2  inserts  his  handspike  in  the  bore,  chocks  it,  and,  assisted  by 


272  MACHINES    AND   APPLIANCES. 

Nos.  1  and  5,  raises  the  muzzle  high  enough  for  No.  4*to  place 
a  half  roller  on  top  of  the  blocks.  The  chase  is  rested  on  this 
half  roller  and  chocked  on  each  side  ;  No.  6  crosses  his  handspike 
under  the  knob  of  the  cascable,  No.  5  taking  hold  of  the  other 
end;  Nos.  1  and  2  bear  down  on  the  handspike  in  the  bore; 
Nos.  5  and  6  lift  on  that  at  the  cascable ;  the  gunner  and  Nos. 

3  and  4  back  the  carriage  until  the  front  rollers  rest  on  the  rear 
ends  of  the  skids  and  the  trail  is  on  the  ground ;  Nos.  3  and  4 
then  place  a  block  and  a  half  block  across  the  skids  under  the 
breech. 

Nos.  5  and  6,  bearing  down  on  their  handspikes  at  the  casca- 
ble, and  Nos.  1  and  2  lifting  on  theirs,  raise  the  muzzle,  and 
Nos.  3  and  4  remove  the  half  block  from  under  the  half  roller. 
The  muzzle  is  in  like  manner  lowered,  and  the  half  block  re- 
moved by  Nos.  3  and  4  from  under  the  breech.  The  muzzle  is 
again  raised,  and  Nos.  3  and  4  remove  the  block  from  under  the 
half  roller  and  place  the  half  roller  under  the  trunnions.  The 
muzzle  is  borne  down,  and  Nos.  3  and  4  remove  the  block  from 
under  the  breech  and  replace  it  by  a  half  block.  The  piece  may 
now  be  slued  in  any  direction,  rolled  upon  blocks,  or  placed  in 
any  required  position. 

To  mount  the  howitzer  when  on  the  skids  and  resting  on  the 

half  block  and  half  roller. 

The  instructor  commands : 

1.  Mount  the  howitzer. 

No.  2  inserts  his  handspike  in  the  bore,  and,  assisted  by  No. 
1,  prepares  to  bear  clown  on  the  muzzle  ;  No.  6  crosses  his  hand- 
spike under  the  knob  of  the  cascable,  and,  assisted  by  No.  5, 
prepares  to  lift  at  the  breech.  At  the  command  Heave  from 
the  gunner,  they  lower  the  muzzle,  and  Nos.  3  and  4  replace 
the  half  block  under  the  breech  by  a  block.  The  breech  is  low- 
ered on  the  block  and  chocked.  The  muzzle  is  next  raised  by  the 
same  numbers  at  the  handspikes,  and  Nos.  3  and  4  insert  a  half 
block  under  the  half  roller,  so  that  the  front  scaffold  thus  formed 
is  3  or  4  inches  in  front  of  the  junction  of  the  chase  and  rein- 
force. The  muzzle  is  now  lowered,  and  a  half  block  placed  by 
Nos.  3  and  4  on  top  of  the  block  under  the  breech. 

The  muzzle  is  next  raised,  and  a  block  placed  by  Nos.  3  and 

4  under  the  half  block,  thus  forming  under  the  chase  a  scaffold 
consisting  of  a  half  roller,  a  half  block,  and  a  block;  Nos.  3  and 
4  now  remove  the  cap-squares,  and  the  gunner,  assisted  by  these 
numbers,  places  the  front  of  the  carriage  on  the  skids,  as  near 
the  gun  as  convenient,  the  trail  resting  on  the  ground ;  Nos.  1 


TO   DISMOUNT   A   15-INCH   GUN.  273 

ami  2  bear  down  on  the  handspike  in  the  bore,  and  Nos.  5  and 
6  lilt  at  that  under  the  knob  of  the  cascable ;  Nos.  3  and  4  re- 
move the  rear  scaffold,  and,  with  the  gunner,  run  up  the  carriage 
until  the  trunnion  beds  are  under  the  trunnions;  Nos.  1  ana  2 
raise  on  their  handspike;  Nos.  3  and  4  remove  the  front  scaf- 
fold, and  the  trunnions  are  lowered  into  their  beds;  Nos.  3  and 
4  put  on  the  cap-squares.  All  then  run  the  carriage  forward 
until  the  front  rollers  touch  the  counter-hurters. 
The  Instructor  commands : 

l.  Mount  the  cabriage. 

No.  2  inserts  his  handspike  in  the  bore,  and,  assisted  by  Nos. 

1  and  5  (the  gunner  bearing  down  on  the  roller  handspike), 
raises  the  front  of  the  carriage ;  Nos.  3,  4,  and  6  at  the  same 
time  push  the  carriage  forward  until  the  front  rollers  pass  over 
the  counter-hurters  and  the  guide  of  the  front  transom  enters 
into  the  guide  space;  No.  6,  with  a  handspike  at  the  trail, 
assisting  to  pass  it  over  the  counter-hurters  and  guiding  tlie 
flanges  of  the  roller  into  the  guide  space. 

No.  6  then  crosses  his  handspike  under  the  knob  of  the  casca- 
ble, and,  assisted  by  No.  5,  lifts  against  the  base  of  the  breech ; 
Nos.  3  and  4  seize  the  trail  handles,  and  Nos.  1  and  2  the  man- 
euvering rings;  the  gunner  bears  down  on  the  roller  hand- 
spike. All  act  together  and  run  the  piece  up  the  chassis  into 
battery. 

Nos.  1, 2, 5,  and  6  now  apply  themselves  to  a  handspike  crossed 
under  the  rear  end  of  the  chassis,  which  they  raise  and  hold  up 
while  the  gunner,  assisted  by  Nos.  3  and  4,  replaces  the  fork  and 
nuts.  The  piece  is  then  run  from  battery,  and  the  gunner, 
assisted  by  Nos.  1  and  2,  puts  in  the  pintle. 

TO    DISMOUNT  A   15 -INCH   GtTTS   FROM    ITS    CABRIAGE   BY 

MEANS    OF  BLOCKS. 

ft&4.  The  implements  required  are:  Two  hydraulic-jacks 
(thirty-ton),  four  pinch-bar  a  (large),  six  handspikes  (cuanoeuver- 
•ing),  eight  wheel-chocks,  four  gun-chocks  (large),  one  trace-rope, 
six  way-planks,  four  shifting-planks,  two  wrenches  (nut),  one 
sledge-hammer,  two  long  rollers  (cradle),  four  small  rollers  (15 
inches  long,  1.5  inch  diameter),  one  ten-foot  pole,  one  carpen- 
ters rule,  one  serew-drwer;  fifty  blocks,  12  by  12  by  44  inches 
(hard  pine);  twelve  blocks,  12  by  6  by  44  inches  (hard  pine); 
eight  blocks,  12  by  4  by  44  inches  (hard*  pine) ;  ten  blocks,  12  by 

2  by  44  iaohf  s  (oak);  ten  blocks,  12  by  1  by  44  inches  (oak);  six 
^mhole  blocks,  8  by  8  by  20  inches  (oak);  four  half  blocks,  8  by 

18 


274  MACHINES   AND   APPLIANCES. 

4  by  20  inches  (oak) ;  four  quarter  blocks,  8  by  2  by  20  inches 
(oak);  two  skids,  12  by  15  by  204  inches  (hard  pine  or  oak);  six 
skids,  8  by  8  by  72  inches  (oak). 

A  four-wheel  truck-wagon  is  convenient  for  removing  the  top- 
carriage  and  chassis. 

The  following  method  is  for  a  gun  mounted  on  a  centre-pintle 
carriage.  Only  slight  changes  are  necessary  to  adapt  it  to  a 
front-pintle  carriage,  and  these  will  readily  suggest  themselves 
to  any  one  performing  the  manoeuvre. 

To  dismount  the  gun. 

535.  Twteve  men  are  necessary:  one  chief-of-detachment, 
one  gunner,  and  ten  cannoneers. 

The  manoeuvre  is  executed  in  the  following  order : 

1st.  Bun  the  gun  into  battery  and  give  it  an  elevation  of  zero. 

2d.  Remove  the  flooring-planks. 

3d.  Remove  from  the  chassis  all  transoms  and  braces  in  rear 
of  the  pintle  transom.  This  makes  a  clear  space  under  the  body 
of  the  gun  for  a  "crib"  to  be  built,  as  shown  in  Fig.  2,  Plate  42. 

4th.  Remove  the  fulcrum  post,  crane,  and  steps  of  the  chassis. 

oth.  Remove  the  large  nuts  from  the  rear  end  of  the  piston 
rods. 

Oth.  Run  the  gun  from  battery  until  the  top-carriage  is  within 
two  or  three  inches  of  the  counter-hurters. 

7th.  Remove  the  truck-wheels  of  the  top-carriage  and  take 
out  the  axles  of  the  same. 

8th.  Remove  the  counter-hurters  from  the  chassis  and  the 
guides  from  the  top-carriage. 

9th.  Place  a  half  block  crosswise  on  each  rail  against  the  hurt- 
ers ;  upon  each  of  these  place  one  of  the  six-foot  skids,  its  rear 
end  resting  on  the  chassis  rail.  This  gives  a  horizontal  foun- 
dation for  the  front  scaffold  to  be  built  under  the  chase  of  the 
gun,  and  a  seat  for  the  jack,  under  the  muzzle,  to  rest  upon. 
(Fig.  1,  Plate  42.) 

10th.  Build  up  a  scaffold  from  the  gun  platform  between  the 
rails  of  the  chassis.  (Fig.  2,  Plate  42.)  This  supports  the  body 
of  the  gun,  while  the  front  scaffold  supports  the  chase.  Both 
should  be  built  crib-fashion,  and  of  the  44-inch  blocks.  Great 
care  should  be  taken  that  these  scaffolds  are  firm  and  true. 

11th.  Place  a  44  by  12  by  12  inch  block  on  end,  resting  on 
the  platform  and  under  the  fulcrum-post  transom  to  support  it. 
On  top  of  this  transom  place  blocks  to  support  the  jack  when 
raising  the  breech  of  the  gun.    (Fig.  1,  Plate  43.) 

12th.  Place  the  jacks,  one  under  the  breech  and  the  other  un- 
der the  muzzle ;  raise  until  the  trunnions  are  clear  of  the  car- 


TO   DISMOUNT  A   15-INCH  GUN.  275 

Tiage,  and  block  up  the  front  and  rear  scaffolds  securely  under 
•the  gun.  The  greatest  care  should  be  observed  in  this  operation 
do  place  the  jacks  squarely  under  the  breech  and  muzzle*  so  that 
the  gun  may  not  roll  and  thus  raise  one  trunnion  higher  than 
the  other.  The  jacks  should  be  worked  alternately,  commenc- 
ing always  with  the  one  under  the  breech,  and  only  two  or  three 
inches  should  be  gained  at  each  lilt.    (Fig.  2,  Plate  42.) 

13th.  Remove  the  front  transom  from  the  carriage,  so  as  to 
admit  of  the  latter  being  run  back  clear  of  the  rear  scaffold. 

14th.  Place  a  trace-rope  through  the  rear  axle-holes  of  the 
^carriage ;  pry  up  the  rear  of  the  carriage,  and  insert  under  each 
shoe  a  small  (1^-inch)  roller. 

15th.  Back  up  the  truck-wagon  against  the  rear  end  of  the 
•chassis  rails.  The  wheels  of  the  wagon  should  rest  on  way- 
>plahks. 

16th.  Haul  on  the  trace-rope  and  draw  back  the  carriage, 
catching  it  on  long  rollers  placed  on  two  way-planks  on  the 
wagon.  (Fig.  2,  Plate  42.)  The  carriage  can  be  drawn  back 
over  the  counter-hunters  in  case  the  latter  are  not  removed. 
When  a  truck-wagon  cannot  be  used,  the  carriage  can,  in  like 
•manner,  be  hauled  back  upon  a  crib  of  blocks  built  in  rear  of  the 
chassis,  from  which  it  may  be  readily  lowered  to  the  ground  by 
means  of  jacks  or  handspikes.    (Fig.  2,  Plate  43.) 

17th.  The  gun  now  being  free  from  its  carriage  and  resting  on 
the  scaffolds,  built  up  as  before  described,  is  lowered,  by  means 
of  jacks,  until  it  rests  on  two  long  skids,  one  end  of  each  rest- 
ing on  the  chassis  rails,  while  the  other  end  rests  on  a  crib  of 
^blocks  built  up  on  the  side  of  the  chassis  to  which  the  gun  is  to 
be  moved.  The  skids  must  be  horizontal  and  on  the  same  level. 
To  this  end  the  front  one  should  rest  across  and  on  the  two  six- 
foot  skids  placed  as  in  "9th."  A  bar  of  railroad  iron  placed  on 
the  front  skid  will  greatly  facilitate  the  next  operation. 

ISth.  Boll  the  gun  over  on  the  skids  until  it  rests  above  the 
cribs.  The  muzzle  is  cut  forward,  either  by  pinching  or  by 
hauling  on  a  trace-rope  attached  to  a  block  or  roller  in  the  muz- 
zle. The  gun  may  now  be  lowered  to  the  ground  by  means  of 
the  jacks,  or,  should  it  be  desired  to  move  it  to  some  other  part 
of  the  works,  it  may  be  placed  on  a  cradle.    (Fig.  1,  Plate  44.) 

To  do  this,  the  cradle  is  placed  parallel  to  the  gun  and  about 
three  feet  from  the  cribs.  The  cradle  rests  upon  five  or  more 
long  cradle  rollers  resting  on  two  way-planks  laid  on  the  ground 
'directly  under  the  mils  of  the  cradle.  (It  is  best  to  double  the 
way-planks  by  laying  them  on  each  other  in  such  manner  as  to 
'break  joints.)  The  rollers  are  securely  chocked.  The  gun  is 
mow  lowered,  by  means  of  the  jacks,  until  it  rests  upon  the  two 


276  MACHINES   AND   APPLIANCES. 

long  skids  placed  across  the  cradle,  the  ends  under fche  gun  rest- 
ing  on  the  cribs — now  reduced  in  height  to  two  blocks^-while- 
the  other  ends  are  supported  by  blocks  on  the  other  side  of  the- 
cradle.     {Fig.  2,  Plate  44.) 

The  gun  is  next  rolled  until  it  rests  squarely  over  the  cradle, 
when  it  is  again  jacked  up  until  the  skids  are  removed,  after 
which  it  is  carefully  lowered  into  its  place  on  the  bolsters  of  the 
cradle.    {Fig.  1,  Plate  45.) 

The  gun  may  be  rolled  over  by  means  of  pinch-bars,  but  more 
easily  by  parbuckling.  A  parbuckle-rope  is  used  for  this  purpose,, 
and  is  Jiauled  upon  by  hand,  or,  better,  by  attaching  to  it  a  tackle 
secured  to  a  holdfast  or  some  other  fixed  object. 

The  same  rope  and  tackle  may  be  advantageously  used  for 
cutting  forward  the  muzzle ;  attaching  the  rope  for  this  purpose 
to  a  block  or  roller  placed  in  the  bore  of  the  gun.     {Fig.  2, 
Plate  45.) 

The  gun  upon  its  cradle  is  moved  by  attaching  to  the  front 
ring  of  the  cradle  a  heavy  rope  (6  to  8  inches  circumference)  and 
hauling  on  it  by  means  of  a  capstan,  or  a  tackle  may  be  used 
instead  of  a  capstan,  in  which  case  a  single-sheave  blodk  is 
hooked  into  the  ring,  and  through  it  a  rope  is  rove,  one  end  of 
which  is  secured  to  a  strong  holdfast  to  the  front,  and  the  other 
hauled  upon  by  tackle  in  the  manner  represented  in  Figs.  1,  2, 
Plate  46.  * 

Way-planks  are  placed  successively  as  the  cradle  moves  for- 
ward, and  as  the  rollers  become  disengaged  at  the  rear  they  are 
placed  in  front,  care  being  taken  to  preserve  an  equal  bearing- 
upon  all. 

In  passing  around  curves,  the  rollers  are  kept  in  the  position 
of  radii  of  the  curve.  This  is  accomplished  by  placing  each  roller- 
in  the  required  position  and  by  driving  the  ends  backward  or 
forward,  as  the  case  may  require.      By  observing  this,  all  un- 
necessary^ jerking  will  be  avoided.    The  cradle  shpuld,  if  possi- 
ble, be  moved  with  the  muzzle  of  the  gun  foremost;  it  then 
engages  the  rollers  in  front  more  freely,  glides  over  inequalities 
with  greater  ease,  and  is  more  readily  directed  in  its  course, — 
results  following  from  the  smallest  weight  being  in  front.     In 
going  up  or  dowu  inclines,  the  rope  should  be  attached  to  the- 
gnn,  by  the  trunnions,  instead  of  to  the  cradle.    This  will  obvi- 
ate any  danger  of  its  slipping  on  the  cradle. 

When  the  inclination  is  great — as  upon  a  ramp — tackling^ 
should  be  used  as  illustrated  in  Figs.  3,  4,  o.  6,  Plate  46. 

Should  the  railway  truck  be  used  instead  of  the  cradle,  the 
gun  is  placed  on  it  by  operations  similar  to  those  for  the  cradle,, 
except  that  the  skids  must  be  supported  entirely  by  the  cribs  at 


TO   DI8MOUNT  A   15-INCH   GUN.  277 

the  sides,  and  not  allowed  to  rest  on  the  truck ;  observing,  also, 
that  the  front  end  of  the  truck  must  always  be  in  the  direction 
towards  which  the  gun  is  to  be  moved. 

Unless  the  ground  is  very  firm  and  the  maneuvering  detach- 
ment skillful,  the  cradle  is  the  safest  and  surest  method. 

To  remove  ike  chassis  from  Us  platform. 

536*  This  may  be  done  by  Jacking  and  blocking  it  up,  and 
placing  under  it  the  cradle  and  rollers.  A  better  way,  however, 
Is  to  use  the  garrison  gin  iustead  of  Jacks,  and  the  four-wheel 
truck- wagon  instead  of  the  cradle. 

The  gin  is  placed  over  the  chassis ;  a  sling-chain,  doubled,  is 
passed  around  the  latter  directly  in  front  of  the  pintle  bolster ; 
to  this  the  hook  of  the  tackle  is  attached. 

The  sling-chain  should  be  of  iron,  at  least  seven-eighths  of  an 
inch  in  diameter.  It  is  better,  however,  to  use  heavy  rope  for 
slinging.  A  gun-sling  made  of  not  less  than  9-inch  rope  is  most 
•convenient,  and  to  use  it  a  cradle  roller,  or  a  beam  of  wood  of  like 
•dimensions,  is  placed  under  the  chassis,  directly  in  front  of  the 
pintle  bolster,  its  ends  projecting  equally  on  the  sides.  Lay  the 
gun-sling  across  and  over  the  chassis;  biing  both  ends  of  it 
under  the  ends  of  the  roller  and  up  together  on  top  of  the  chas- 
sis, where  the  free  end  is  drawn  through  the  eye,  bent  into  a 
"knot,  and  stoppered.  The  book  is  attached  to  the  sling  by  lash- 
ing with  a  trace-rope,  not  less  than  six  turns  being  taken  for 
this  purpose. 

Blocks  of  wood,  with  rounded  edges,  are  placed  against  the 
-sides  of  the  chassis  mils,  under  the  sling,  to  prevent  the  sharp 
-edges  of  the  chassis  from  cutting  the  rope. 

The  chassis  is  then  raised  until  the  truck  can  be  backed  under 
it.  The  wheels  of  the  truck  rest  on  way-planks,  and  the  truck 
coupled  to  such  length  that  when  the  chassis  is  lowered  the  rear 
traverse  -wheels  will  be  in  front  of  the  front  bolster,  and  the 
front  traverse-wheels  in  rear  of  the  rear  bolster  of  the  truck. 
(Plate  47.)  The  chassis  is  lowered  so  that  the  rails  will*  rest  on 
the  bolsters  between  the  iron  projections  at  their  ends.  The 
truck,  with  the  chassis,  can  now  be  moved  wherever  desired. 

The  chassis  is  replaced  and  the  gun  remounted  by  operations 
the  reverse  of  the  foregoing. 

The  precautions  necessary  to  be  observed  in  all  mechanical 
manoeuvres  with  artillery,  multiply  rapidly  with  the  weight  of 
the  piece. 

With  the  15-inch  gun,  all  implements  and  material  should  be 
of  the  most  perfect  kind,  and  no  doubt  should  be  allowed  as  to 
strength  of  parts  to  sustain  the  weight  or  pressure  required  of 


278  MACHINES    AND   APPLIANCES. 

them.    The  utmost  care  should  be  taken  to  avoid  all  sudden  shocks* 
and  jerking  movements, 

537.  Another  method  of  mounting  guns  on  iron  carriages,  i» 
to  block  up  the  piece  to  the  proper  height,  and  then  assemble- 
the  chassis  and  carriage  under  it. 

To  do  this,  place  the  piece  on  the  platform  in  such  position  as- 
to  bring  the  chassis  in  its  proper  place  with  reference  to  the 
pintle  and  traverse  circles ;  raise  the  muzzle  and  breech  alter- 
nately by  means  of  the  jack,  supporting  the  gun  on  two  scaf- 
folds of  blocks  placed  in  front  and  in  rear  of  the  trunnions  f 
assemble  the  chassis  in  position;  place  one  cheek  of  the  top- 
carriage  on  the  chassis  rail,  with  the  trunnion  bed  directly  under 
the  trunnion,  and  bolt  the  transoms  to  it ;  place  the  other  cheek 
in  position,  and  bolt  it  to  the  transoms;  lower  the  trunnions 
into  their  holes  and  remove  the  block. 

To  di&mount  a  gun,  proceed  in  the  inverse  manner. 

Another  method,  when  the  top-carriage  has  not  been  taken 
apart,  is  as  follows :  Mount  the  chassis  on  the  platform  and  the 
top-carriage  on  the  chassis,  and  then  run  the  top-carriage  into 
battery;  bring  the  gun  upon  the  cradle  or  skidding  until  it 
is  parallel  to  a  convenient  portion  of  the  chassis;  roll  the 
gun  over  the  chassis,  having  the  breech  projecting  beyond  the- 
rear  end  of  the  chassis ;  raise  it  by  blocking  under  the  breech 
beyond  the  rails  and  under  the  muzzle  by  a  pier  of  blocks  be- 
tween the  rails,  or  by  a  pier  of  blocks  outside  of  each  rail  with 
a  skid  laid  across.  The  piece  is  raised  until  the  trunnions  are 
high  enough  to  permit  the  top-carriage  being  moved  back  under 
thera,  when  the  piece  is  lowered  into  the  trunnion  beds  and  the 
scaffolding  removed. 

When  a  pier  of  blocks  is  placed  between  the  chassis  rails,  a  gin 
is  used  for  suspending  the  muzzle  until  the  pier  is  removed  and. 
the  carriage  moved  back  under  the  trunnions. 

A  gin  may  be  advantageously  used  for  raising  heavy  guns 
upon  blocks.  To  do  this,  supposing  the  piece  to  be  lying  on  the 
ground,  insert  a  skid  or  similar  piece  of  timber  into  the  muzzle ; 
erect  the  gin  over  the  muzzle  and  attach  the  tackle  to  the  skid  ; 
raise  the  muzzle  and  place  a  block  under  the  piece  just  in  rear 
of  the  centre  of  gravity ;  lower  the  muzzle  and  block  up  under 
the  breech ;  again  raise  the  muzzle  and  block  up  on  the  fulcrum;, 
lower  the  muzzle  and  block  up  under  the  breech ;  and  continue: 
this  operation  until  the  piece  is  at  the  required  height. 


I 


DESCRIPTION   OF   THE   GUN-LIFT.  279 

TO    PLACE    A    13-OTCH    MORTAR,   MOUNTED   ON    ITS  TJAR- 

RIAGE,   ON  A   TRUCK-WAGON. 

538.  implements  specially  required  :  One  gin,  of  size  larger 
than  garrison  gin;  one  fall,  ol  large  size  (5  to  7  inches);  one 
quadruple  block,  one  triple  block,  four  sling-chains  (links  not 
less  than  0.75  inch  in  diameter),  one  four-wheel  truck^wagon, 
one  clevis  for  mortar  lug.  Instead  of  the  sling-chains,  two  gun- 
slings  may  be  used.  These  should  be  of  rope  not  less  than  nine 
inches  in  circumference. 

Twelve  men  are  necessary  :  one  chief-of-detachment,  one  gun- 
ner, and  ten  cannoneers. 

Remove  the  upper  step  from  the  bed  and  depress  the  mortar 
until  its  axis  is  horizontal ;  raise  the  gin  over  the  mortar  and 
rig  the  tackle ;  attach  the  clevis  to  the  clevis  lug  and  hook  the 
lower  block  to  it ;  pass  a  sling-chain  under  the  rear  notches  of 
the  bed  and  up  over  the  mortar,  in  front  of  the  clevis  lug,— this 
is  to  prevent  the  rear  end  of  the  carriage  from  sagging  when  the 
mortar  is  raised ;  work  the  windlass  until  the  carriage  is  high 
enough  to  pass  the  wagon  under  it ;  the  wagon,  having  been 
coupled  short  enough  to  receive  the  mortar  bed  on  both  bol- 
sters, is  run  under  and  the  mortar  lowered  upon  it. 

Should  there  be  no  clevis  lug  on  the  mortar,  two  sling-chains 
are  used,  passing  under  the  front  and  rear  notches  of  the  bed 
and  crossing  each  other  on  top  of  the  mortar.  The  lower  block 
of  the  gin  tackle  is  hooked  at  the  crossing,  and  the  operation  of 
raising  is  as  before  described. 

The  mortar  thus  mounted  on  a  wagon  can  be  moved  by  band 
short  distances,  and  with  eight  horses  may  be  transported  over 
level  and  firm  roads. 

Instead  of  the  gin,  one  trestle  of  the  gun-lift  may  be  used  for 
the  foregoing  operation.  It  is  set  over  the  mortar,  and  the  ma- 
noeuvre is  proceeded  with  as  with  the  gin.    (Fig.  1,  Plate  48.) 

Description  of  the  Gun-lift. 

{Plates  48,  49.) 

539*  A.  Sill,  with  mortises  to  receive  the  legs  of  the  trestles. 

B.  Brace  sill,  notched  to  fit  on  sill,  with  a  bolt  and  key  to 
secure  it  in  its  place  and  a  cast-iron  seat  for  end  of  adjusting 
screw  of  brace  to  rest  in. 

C.  Legs  of  trestle,  bolted  and  keyed  together  at  top. 

D.  Brace,  with  adjusting  screws  attached  to  foot.  One  brace 
on  each  trestle  has  cleats  to  form  a  ladder. 


280  MACHINES   AND   APPLIANCES. 

E.  Cap,  with  a  shallow  mortise  near  each  end  to  receive  ends 
of  lege  and  braces,  and  a  hole  to  receive  large  bolt  for  securing 
it  to  legs.  These  bolts  are  keyed  below,  and  their  heads  project 
above  the  cap  about  three  inches,  and  serve  as  dowels  to  secure 
the  bolsters. 

F.  Bolsters,  resting  on  cap,  having  a  clevis  at  centre  of  gravity 
for  hoisting  it  in  position  and  a  mortise  for  hoisting-bar  to  pass 
through. 

G.  Bracket,  fastened  to  cap  by  a  bolt,  around  which  it  turns. 
H.    Staging-plank^  resting  on  brackets. 

I.      Fulcrum,  resting  in  mortise  in  bolster. 

J.  Lever,  one  end  resting  in  fulcrum  and  the  other  on  hy- 
draulic-jack, and  having  a  mortise  through  which  the  hoisting- 
bar  passes. 

K.  Hoisting-bar,  with  hooks  on  lower  end  for  sllng-chainsand 
holes  at  intervals  to  receive  supporting  pins. 

L.  Shears*  for  hoisting  into  their  places  the  bolster,  levers, 
fulcrum*,  and  jacks. 

M.  Hydraulic-jack,  for  raising  end  of  lever,  and  thereby  the 
weight. 

Each  gun-lift  is  provided  with  two  sets  of  caps  and  bolsters. 
One  of  these  sets  has  the  mortises  for  the  hoisting-bar  through 
its  middle ;  this  is  intended  for  centre-pintle  carriages.  The 
other  set  has  mortises  much  nearer  one  end  than  the  other,  and 
is  for  front-pintle  carriages.  The  latter  arrangement  is  intended 
to  permit  the  carriage  to  be  traversed  from  under  the  gun,  when 
it  is  raised,  or  under  it,  when  it  is  being  mounted. 

When  weights  are  not  excessive — that  is,  not  exceeding,  say, 
fifteen  tons — and  can  be  slung  with  a  single  sling,  but  one  trestle 
need  be  used.  This  would  be  the  case  with  mortars,  gun  car- 
riage*, and  like  weights. 

The  jacks  used  must  be  of  a  power  equal  to  the  weight  to  be 
raised,  as  there  is  nothing  gained  for  them  by  way  of  leverage. 

Twelve  men  are  necessary  to  erect  the  gun-lift  and  mount  or 
dismount  a  15-inch  gun. 

Implements  specially  required :  Two  hydravlic-jacks  (30-ton, 
or  one  30- ton  and  one  15-ton),  two  mauls,  two  hammers,  one 
measuring-rod  (12  feet),  one  spirit-level  (carpenter's). 

If  the  carriage  and  chassis  are  to  be  moved,  the  following  will 
be  required  in  addition ;  One  cradle  (or  truck-wagon),  six  cradle 
rollers,  twelve  wheel -chocks,  four  way -planks,  two  shifting  - 
planks. 

A  sufficient  number  of  44-inch  blocks  of  various  thicknesses 
should  be  at  hand  for  any  purpose  required  of  such  material. 


DESCRIPTION   OF   THE  GUN-LIFT.  281 

To  assemble  and  raise  the  gun-lift. 

540.  Place  tbe  sills  parallel  to  each  other  at  the  required 
distance  apart  and  on  the  spot  where  the  trestle  is  to  stand.  It 
will  be  convenient  to  have  a  wooden  rod  of  a  length,  equal  to  the 
proper  distance  between  the  sills.  Lay  down  the  brace  sills  and 
key  them ;  take  two  legs,  bring  together  the  two  ends  which 
iorm  tbe  mitre  joint,  pass  the  bolt  through  them,  and  drive  in 
the  key ;  raise  one  leg  above  the  other,  insert  the  head  of  the 
legs  into  the  mortise  in  the  cap,  put  iu  the  bolt,  and  drive  in  the 
key.  At  the  same  time  two  other  men  have  gone  through  the 
-same  operation  with  tbe  other  two  legs. 

Place  the  ends  of  the  legs  that  are  on  the  ground  close  to  the 
mortises  in  tbe  sills ;  all  take  hold  of  the  cap  and  raise  it,  bring- 
ing the  trestle  on  ite  feet  and  placing  the  legs  in  the  mortises  in 
che  sills. 

A  pole  with  a  notch  in  the  end,  or  hook  like  a  boat-hook,  will 
be  convenient  in  raising  the  trestle  after  the  cap  is  too  high  to 
hold  it  with  the  hands ;  or  the  trestle  may  be  raised  by  the  shears 
In  the  same  way  as  the  bolster,  if  the  party  be  deficient  in  force, 
or  if  for  other  reasons  it  be  deemed  desirable.  Correct  the  posi- 
tion of  the  trestle,  if  it  be  necessary,  so  as  to  bring  the  mor- 
tise for  the  hoisting-bar  directly  over  the  centre  of  gravity  of 
the  weight  to  be  raised.  Put  up  the  braces,  varying  their  length 
.as  may  be  required,  by  turning  the  screw  in  the  foot,  until  they 
shall  have  a  good  bearing  when  the  legs  are  vertical,  which  is 
determined  by  a  plumb-line  or  spirit-level. 

To  raise  tbe  bolster,  a  pair  of  light  shears  is  provided.  Place 
them  so  that  when  raised  the  head  shall  be  over  the  middle  of 
the  cap  of  the  trestle ;  hook  the  pulley-hook  in  the  link  provided 
for  the  purpose ;  fasten  two  guys  to  the  bead,  one  to  the  front 
and  the  other  to  the  rear;  raise  the  shears  and  make  fast  the 
guys ;  hook  the  pulley  to  the  clevis  of  the  bolster  and  raise  it 
to  its  place  on  the  cap ;  raise  the  staging-plank  and  lay  them 
on  the  brackets. 

Two  men  ascend  the  steps  on  the  brace  to  tbe  top  of  the  trestle 
and  receive  the  fulcrum,  lever,  and  jack,  which  are  hoisted  to 
them  in  turn,  and  place  them  in  position.  The  hoisting-bar  is 
brought  by  the  men  on  the  ground,  who  insert  it  into  the  mor- 
tise in  the  cap  and  bolster,  and  raise  it,  assisted  by  those  on  the 
trestle,  until  it  be  in  position. 

To  raise  the  weight. 

Pass  •  a  filing  around  the  weight,  bringing  the  ends  over  the 
hook  on  the  end  of  the  hoisting-bar,  taking  in  all  of  the  slack. 
Jfcing  the  lever  down  on  the  head  of  the  jack ;  put  iu  tbe  pin 


282  MACHINES   AND   APPLIANCES. 

over  it  and  through  a  hole  in  lifting-bar ;  commence  pumping, 
and  raise  the  weight  the  full  lift  of  the  jack ;  insert  the  pin  in 
the  hole  in  lifting-bar  above  the  bolster  and  run  down  the  head 
of  the  jack  as  far  as  it  will  go;  bring  the  lever  down  as  at  first, 
and  continue  the  operation  as  already  described.  The  weight 
should  not  be  left  on  the  jack  for  any  length  of  time,  but  on  the  pin. 

To  mount  a  lo-inch  gun  with  the  gun-lift. 

541*  The  platform  is  supposed  to  have  nothing  on  it.  Bring 
the  gun  onto  the  platform  by  means  of  the  cradle,  or  truck  and 
portable  railway,  the  muzzle  to  the  front,  the  vent  uppermost,, 
and  leave  it  in  such  a  position,  with  the  muzzle  about  two  feet 
in  rear  of  where  the  end  of  the  chassis  will  come,  that  when  the 
gun  shall  be  raised  vertically  the  carriage  can  be  placed  on  its 
pintle  and  directly  under  the  gun ;  place  the  shears  midway 
between  the  place  where  the  two  trestles  are  to  stand ;  raise  the 
trestles  and  place  them  over  the  gun  so  that  one  hoisting-bar 
shall  be  over  the  centre  of  the  neck  of  the  cascable  and  the  other 
about  two  feet  from  the  muzzle ;  raise  the  gun  to  its  full  height 
as  already  described  for  raising  a  weight ;  remove  the  truck, 
bring  the  chassis  (on  a  truck),  and  run  it  between  the  legs  of 
the  trestles  under  the  gun;  remove  the  truck  and  place  the 
chassis  on  the  pintle ;  bring  the  top-carriage  and  place  it  on  the 
chassis,  placing  the  trunnion  beds  under  the  trunnions;  lower 
the  gun  into  its  place,  and  remove  the  gun-lift. 

If  the  gun  and  carriage  be  already  on  the  platform,  or  if  the 
peculiar  position  of  the  platform  be  such  as  to  render  the  forego- 
ing method  impracticable,  the  following  plan  may  be  executed  : 

Place  the  gun  in  such  a  position  that  the  axis  of  the  bore  shall 
be  in  the  same  vertical  plane  as  the  central  line  of  the  chassis 
when  the  latter  shall  be  in  place  ;  move  the  chassis  parallel  and 
close  to  the  gun,  the  top-carriage  run  well  to  the  front;  put  up 
the  trestles  over  the  gun  and  chassis,  both  of  them  being  between 
the  legs  of  the  trestles;  hoist  the  gun,  raise  and  slide  the  chassis 
by  means  of  the  jacks  under  the  gun  and  over  its  pintle ;  run 
the  top-carriage  back  under  the  gun,  and  lower  it  into  its  place. 

To   DISMOUNT   A   10-INCH  SMOOTH-BORE  (CASEMATE  GTTN) 

BY  MEANS   OF   BLOCKS. 

{Figs.  1,  2,  Plate  50.) 

542*  The  detachment  consists  of  one  chief,  one  gunner,  and 
ten  cannoneers. 
Implements:  Two  skids,  96  by  12  by  12  inches;  seventeen 


TO   DISMOUNT   A    10-INCH   SMOOTH-BORE.  28& 

• 

blocks,  44  by  12  by  12  inches;  five  blocks,  44  by  12  by  6  inches; 
five  blocks,  44  by  12  by  4  inches ;  five  blocks*  44  by  12  by  2  inches ; 
eight  whole  blocks,  four  half  blocks,  four  quarter  blocks,  one 
bar  (railroad  iron),  two  hydraulic -jacks,  two  pinch  -bars,  two- 
hammer-wrenches,  two  iron  wrenches,  four  fongr  handspikes,  two 
manasuvering-bars  (iron),  one  two-foot  rule*  two  muzzle-chocks, 
two  breech-chocks,  one  tar^e  chock,  five  wheel-chocks. 

To  dismount  the  piece. 

543*  Bun  the  piece  from  battery  until  the  carriage  touches  the 
counter-hurters ;  throw  it  oucof  gear;  remove  fulcrum  post,  rear 
transom,  rear  guides,  and  depress  the  piece  as  far  as  possible. 

Under  the  rear  of  the  chassis  rails,  and  parallel  to  theui,  lay 
two  12-inch  blocks,  their  front  ends  touching  the  traverse- 
wheels;  across  these  place  two  6-inch  blocks  about  six  inches 
apart,  the  front  edge  of  the  front  one  directly  under  the  rear 
edge  of  the  middle  transom  of  the  top-carriage ;  across  these 
rest  on  each  side  a  whole  and  a  half  block,  the  whole  blocks  one 
foot  apart,  their  front  ends  on  a  line  with  the  front  edge  of 
the  6-inch  block  under  the  middle  transom  ;  lay  a  half  block  be- 
tween the  whole  blocks  for  a  support  for  the  hydraulic-jack. 
Under  the  chassis,  in  front,  place  transversely  two  i2-inch  blocks 
about  15  inches  apart,  the  rear  one  under  the  rear  part  of  the  fork; 
across  these  place  a  6-inch  block  to  support  the  hydraulic-jack ; 
across  the  chassis  rails,  and  resting  against  the  hurters,  place  two 
quarter  blocks ;  let  the  front  ends  of  the  6-inch  blocks  rest  upon 
these,  the  rear  ends  bearing  upon  the  chassis;  build  across  the 
rear  ends  of  the  6-inch  blocks,  with  12-inch  and  6-inch  blocks  (or 
thinner  pieces  if  necessary),  until  the  muzzle  is  reached  ;  block, 
up  securely  and  chock  the  breech,  and,  by  means  of  the  jack,, 
raise  the  muzzle  until  the  gun  has  a  slight  elevation ;  then  raise 
the  breech  and  muzzle  alternately  until  two  whole  blocks,  in 
addition  to  those  already  placed,  can  be  put  under  the  former, 
aud  one  12-inch  and  two  6-inch  blocks  under  the  latter ;  run  the 
top-carriage  forward  until  the  front  ends  nearly  touch  the  block- 
ing in  front ;  remove  eccentric  sockets,  wheels,  axle,  and  right 
front  guide  ;  raise  the  carriage,  and  under  it,  front  and  l-ear  aud 
across  the  chassis,  place  two  iron  raanoeuveriug-bars ;  back  up 
the  casemate  truck,  chock  the  wheels,  and  slide  the  top-carriage- 
upon  it.  The  truck  having  been  removed,  two  skids  are  placed 
under  the  gun.  front  and  rear,  between  the  blocking,  their  inner 
ends  ends  resting  upon  both  chassis  rails,  the  outer  upon  cribs- 
built  of  12-inch  blocks  as  near  the  chassis  as  possible.  The  gun- 
having  been  lowered  upon  the  skids,  the  muzzle  resting  upon 
the  railroad  iron  so  that  it  can  be  cut.  it  is  rolled  an  til  it  rests: 
directly  over  the  cribs,  raised  sufficiently  to  permit  the  skids  to- 


284 


MACHINES   AND   APPLIANCES. 


5be  removed,  and  lowered  to  the  ground  or  upon  the  casemate 
truck,  as  may  be  desired. 
The  gun  is  mounted  by  inverse  means. 

Precautions  to  be  observed. 

544.  After  the  breech  is  sufficiently  raised,  the  two  upper 
whole  blocks  are  backed  up  by  two  others  placed  in  rear,  in  order 
to  give  a  broader  bearing  and  prevent  the  possibility  of  upsetting. 

'The  gun  should  never  have  much  elevation  when  being  raised 
by  the  jacks,  as  it  is  liable  to  slide  to  the  rear  and  upset  the  jack. 
'This  is  especially  important  when  the  gun  is  being  mounted  be- 
fore the  top-carriage  has  been  run  back.  In  remounting  the 
gun,  care  must  be  taken  that  it  is  not  too  far  to  the  rear  (the  dis- 
tance from  the  rear  of  the  chassis  to  a  point  directly  under  the 
axis  of  the  trunnions  is  5  feet  1  inch) ;  should  this  occur,  how- 
ever, the  carriage  can  be  run  farther  to  the  rear  by  removing 
the  counter-hurters.  Should  the  gun,  upon  being  foiled  back 
over  the  chassis,  have  its  trunnions  in  line,  but  not  rest  directly 
■over  the  carriage,  it  may  be  moved  sidewise,  by  raising  it  with 
the  jack,  and  then  lowering  it  slowly  upon  a  large  ground-chock. 

If  the  blocking  under  the  breech  is  placed  too  far  forward,  it 
will  not  allow  the  carriage  to  be  run  sufficiently  far  to  the  rear 
to  receive  the  trunnions  in  the  trunnion  bed. 

Care  must  always  be  taken  to  arrange  the  blocking  and  crib- 
work  so  that  it  will  not  interfere  with  the  free  manipulation  of 
the  jacks. 

The  foregoing  is  for  a  gun  mounted  on  a  casemate  carriage. 
When  mounted  on  a  barbette  carriage,  the  operation  differs  but 
1  it  tie  from  the  former. 

Sheabs. 

545.  Shears  are  used  for  lifting  heavy  weights  over  the  face 
-of  a  wall  or  cliff,  or  in  other  situations  where  the  gin  could  not 
Vbe  used  for  want  of  footing  for  the  pry-pole. 

All  shears  are  constructed  and  erected  on  the  same  principle. 
They  consist  of  two  spars  of  suitable  size  for  the  weight  to  be 
raised.    The  following  will  serve  as  a  guide  : 

Spars. 


Weight. 

DlAMXTJBR. 

IiBNOTH. 

Tons. 

5 
12  and 
upwards. 

Inches. 

Head  6  to  9  heel. 
"    10  to  14  " 
"    14  to  20  " 

Feet. 

80  to  80 
30  to  40 
30  to  45 

SHEARS.  285* 

The  upper  and  lower  ends  are  respectively  called  the  headT 
and  heel,  and  the  part  where  the  lashing  is  applied  is  termed  the- 
cross. 

The  stores  necessary  to  equip  a  pair  of  shears  are : 

Gin  tackles — Two  single  blocks,  two  double  blocks. 

Main  tackle — One  double  block,  one  treble  block,  one  snatch 
block. 

Cordage— Main-tackle  fall,  100  fathoms  3  to  5  inch  Manila 
rope;  guys,  50  fathoms  3  to  6  inch  Manila  rope;  head  lashing, 
10  fathoms  3  to  4  inch  Manila  rope ;  heel  lashing  (two  each),  10 
fathoms  3  to  4  inch  Manila  rope ;  contingencies  (two  each),  50  • 
fathoms  3  to  4  inch  Manila  rope. 

Straps — Main  tackle,  one  fathom  6-inch  Manila  rope ;  snatch 
block,  one  fathom  4-inch  Manila  rope ;  holdfasts  (six),  each  made 
of  one  fathom  4-inch  Manila  rope ;  contingencies  (six),  each  made 
of  a  half-fathom  of  4-inch  Manila  rope. 

Spun-yarn  for  mousing,  stops,  Ac,  one  ball  of  100  fathoms. 

Two  cleats  for  heels,  to  prevent  the  lashing  from  slipping  up, 
made  by  cutting  lengthwise,  diagonally,  a  piece  of  6  by  6  ineh 
scantling  2  feet  long.  These  cleats  are  spiked  to  the  heels  Cl- 
inches from  the  bottom.  Twelve  stakes  for  holdfasts  for  guys, 
t>  feet  by  6  feet  by  8  inches;  four  stakes  for  heel -posts;  two 
shoes  for  heels,  6-inch  plank,  15  feet  by  15  feet. 

To  rig  the  shears. 

(Fig.  1,  Plate  51.) 

546.  Lay  the  heads  of  the  spars  on  a  trestle  about  three  feet  • 
high,  the  right  leg  above  the  left,  so  that  they  cross  at  about 
twice  their  thickness  from  the  ends,  with  the  heels  in  their 
proper  position. 

Pass  the  head  lashing  as  described  in  par.  480,  or  if  a  very  heavy 
weight  is  to  be  raised,  as  follows :  Take  a  good  piece  of  3J  or 
4  inch  rope,  well  stretched,  middle  it,  and  make  fast  to  the  shear- 
leg,  below  the  cross ;  with  one  end  pass  the  requisite  number  of 
figure-of-eight  turns  around  both  spars,  heaving  each  turn  well 
taut,  and  hitch  the  end  to  the  upper  part  of  the  shear  leg;  with 
the  other  end  pass  riding  turns  around  both  legs,  fllliuo;  up  the 
intervals  between  the  first  turns;  come  up  with  the  hitch  of 
the  first  end,  and  pass  (rapping  turns  around  all  parts  of  the 
lashing  between  the  shears;  finish  with  a  square  knot,  and  stop- 
the  ends  back  with  a  good  spun-yarn  stop.  If  necessary,  tighten 
up  with  wedges. 

Lay  the  middle  of  the  back  guy  in  the  cross ;  bring  the  left- 
lmnd  end  up  around  the  right  leg  and  over  the  head  of  the  left 
leg;  then  carry  the  right-hand  end  around  under  both  legs;  let  it 


286  MACHINES   AND   APPLIANCES. 

•cross  over  the  left-hand  end,  and  seize  them  together  with  spun- 
yarn. 

Make  a  bowline  knot  in  the  end  of  the  fore  guy  and  slip  it 
over  the  head  of  both  legs. 

Lay  the  middle  of  the  main-tackle  strap  under  the  cross  above 
the  fore  guy;  bring  the  ends  up  over  the  cross;  hook  the  upper 
'block  to  them  under  the  cross  below  the  fore  guy,  and  mouse  it, 
taking  care  that  the  splice  comes  in  the  middle  of  the  strap  and 
*that  the  fall  leads  to  the  rear. 

Drive  the  heel-posts  on  each  side  the  heels  about  a  foot  toward 
the  head,  and  one  foot  outside ;  lay  the  shoes  under  the  heels ; 
make  a  timber  hitch  around  the  inner  posts  with  the  heel  lash- 
ings; pass  three  turns  over  the  legs  below  the  cleats,  and  bitch 
the  lashings  to  the  outer  posts. 

Drive  four  holdfasts  for  each  back  guy  as  follows :  Two  on 
each  side  the  line  of  the  legs  prolonged,  three  feet  apart,  and 
two  six  feet  in  rear  of  these. 

Lay  the  ends  of  the  guy  straps  over  the  front  stakes ;  connect 
each  pair  of  front  and  rear  stakes  with  a  strap  twisted  up  taut  to 
insure  the  strain  being  distributed  properl)*. 

Drive  two  holdfasts  for  the  fore  guy,  one  in  rear  of  the  other, 
'in  the  prolongation  of  the  axis  of  the  shears. 

Hook  the  upper  blocks  of  the  guy  tackles  to  a  bowline  in  the 
end  of  the  guys,  and  the  single  block  to  the  guy  strap,  and 
mouse  them  all. 

Ordinarily  the  fore  guy  can  be  worked  without  a  tackle,  be- 
laying it  over  the  holdfasts,  first  taking  a  round  turn  over  the 
•one  next  the  shears. 

If  not  too  heavy,  the  shears  may  be  raised  by  lifting  the  head 
iiucl  hauling  on  the  guy  tackles,  slacking  the.heel  lashings  as  re- 
quired, and  tending  the  fore  guy  carefully  to  prevenfthe  shears 
Jailing  over  toward  the  rear. 

When  raised,  hook  the  snatch  block  to  a  strap  placed  below 
the  cleat  on  either  leg. 

If  the  shears  are  too  heavy  to  raise  in  this  way,  bring  both  guys 
together  at  the  heels;  form  a  crutch  by  lashing  together  two 
poles  (or  use  the  legs  of  the  garrison  gin) ;  place  the  guys  in  this 
-crutch ;  pass  the  end  of  a  small  rope  over  both  guys,  in  front  of 
the  crutch,  down  under  the  lashing,  and  take  a  rolling  hitch 
with  it  around  one  of  the  guys  in  rear  of  the  crutch ;  haul  the 
rope  well  taut,  and  secure  it  to  the  lower  end  of  the  crutch  leg. 

Raise  the  crutch  with  an  inclination  of  one-sixth  to  the  front, 
And  heave  up  the  shears  by  the  guy  tackles.  When  the  cratch 
•ceases  to  act,  slack  it  to  the  ground  by  the  small  rope. 

In  general,  the  inclination  or  rake  of  the  shears  should  not 


SHEARS.  287 

exceed  20  degrees,  or  four-elevenths  of  their  height,  and  each 
leg  should  have  about  one-half  this  inclination.  In  this  position 
the  strain  on  the  guys  will  never  exceed  oue-lialf  the  weight. 
Allowance  of  seven  or  eight  degrees,  or  one  foot  in  eight,  should 
be  made  for  the  stretch  of  the  guys. 

The  diagram  (Fig.  2,  Plate  51)  will  serve  as  a  guide  iu  plac- 
ing shears,  holdfasts,  &c. 

Make  A  B=  JCE. 

C  D=*  2  a  b. 


E  F    '  -at  least  2  A  C. 


EG/ 


When  the  locality  will  not  admit  of  rigging  the  shears  in  posi- 
tion as  described,  they  may  be  raised  from  the  foot  of  the  wall 
or  cliff  by  means  of  a  gin  or  lighter  shears  in  the  following  man- 
ner :  Pass  the  shear  lashing  and  attach  the  front  guy ;  lash  a 
.stout  spar  across  the  legs  about  two  feet  above  the  centre  of 
gravity,  giving  the  heels  the  proper  spread ;  fasten  a  small  rope 
to  each  heel  to  serve  as  guys ;  hook  the  gin  tackle  to  a  strap 
finnl}r  attached  to  the  middle  of  the  cross-spar,  and  heave  away, 
tending  the  guys  carefully.  As  the  head  of  the  shears  comes 
above  the  crest  of  the  wall,  put  on  the  back  guys  and  main-tackle 
strap,  and  hook  on  the  tackle ;  mouse  all  hooks;  raise  the  shears, 
place  the  heels  in  the  shoes,  pass  the  heel  lashings,  set  up  the 
guys,  and  lower  the  gin  to  the  ground  by  means  of  its  tackle, 
leaving  the  spar  in  position. 

Use  of  the  gin  as  shears. 

54 1*  When  the  garrison  or  casemate  gin  is  used  as  shears' 
the  pry-pole  is  replaced  by  a  parting  block  of  the  same  diameter* 

The  guys  are  attached  as  follows  :  Middle  the  rope  for  the  back 
guys ;  push  the  bight  through  the  clevis  from  below  and  slip  it 
.around  both  legs ;  haul  the  ends  back  tight  and  lay  them  over 
the  head  of  the  gin  to  the  rear,  each  part  lying  between  the 
nearest  leg  and  the  parting  block,  taking  care  to  place  canvas 
under  the  ropes  to  prevent  chafing. 

The  fore  guy  is  hitched  around  the  clevis  bolt. 

A  single  back  guy  may  be  used,  formed  of  a  tackle  of  the  same 
£ize  as  the  gin  tackle,  hooked  into  a  strap  applied  as  described 
for  the  guy-ropes.  In  this  case  particular  care  must  be  taken 
to  bring  the  axis  of  the  shears  in  the  vertical  plane  containing  the 
holdfast  and  the  centre  of  gravity  of  the  weight  to  be  lifted. 

The  shears  are  lowered  by  slacking  the  guys  and  heel-ropes,  or 
by  using  small  shears.  When  no  capstan  is  available,  a  windlass 
may  be  improvised  as  follows : 

Nail  a  strong  cleat  on  the  lower  side  of  each  leg,  three  feet 


288  MACHINES    AND   APPLIANCES. 

from  the  heel,  butt  end  down ;  lay  a  round  spar  a  little  more- 
than  one-third  the  length  of  the  shears  across  the  legs,  one  foot 
above  the  butt  of  the  cleats,  and  pass  a  strong  lashing,  f  rap  pin  g- 
it  loosely  between  the  spar  and  legs,  taking  care  to  have  the 
lashings  of  equal  length;  grease  the  spar  under  the  lashing? 
'pass  a  strap  around  e!ach  end  of  the  spar,  put  one  end  through 
the  other,  take  a  round  turn  around  the  spar,  and  put  a  hand- 
spike through  the  free  end,  to  be  used  as  $,  lever  to  turn  the 
windlass.  The  straps  should  be  nailed  to  the  spar  to  prevent 
slipping.  Additional  levers  may  be  applied  in  the  same  manner 
if  required. 

The  windlass  is  chocked  by  allowing  the  ends  of  two  hand- 
spikes (or  more)  to  touch  the  ground. 

The  officer  in  charge  of  the  work  should  place  himself  where 
he  can  carefully  observe  the  working  of  the  entire  structurer 
particular  attention  being  paid  to  the  rake  of  the  lege  and  the 
security  of  the  several  holdfasts. 

No  person  should  be  permitted  to  stand  or  pass  under  the  shears- 
while  a  weight  is  being  raised. 

The  shears  proposed  by  the  Ordnance  Department  to  be  fur- 
nished for  hoisting  a  15-inch  gun  are  represented  on  Plates  52: 
and  53. 

Derricks. 

{Fig.  3,  Plate  51.) 

548*  The  derrick  is  a  machine  used  for  hoisting  or  .lowering* 
heavy  bodies  to  or  from  the  top  of  vertical  walls  or  similar 
places.  It  usually  consists  of  one  spar  or  leg;  but  the  one- 
employed  for  raising  15-inch  guns  consists  of  two  legs  made 
of  round  spars  of  yellow  pine,  29  feet  long,  11  inches  diameter 
at  the  foot  and  9  inches  at  the  top ;  one  sill,  half  round,  16  feet 
long  and  11  inches  in  diameter;  one  cap,  half  round,  8  feet 
long  and  9  Inches  in  diameter;  two  iron  straps,  with  keys  and 
wedges  for  securing  cap  to  legs.  Xear  each  end  of  the  sill,  on 
the  square  side,  is  a  mortise,  into  which  fits  the  tenon  on  the- 
foot  of  the  leg.  The  cap  is  similarly  mortised  to  receive  the 
top  of  the  legs,  and  is  held  fast  in  this  position  by  the  straps 
fitting  over  it  and  keyed  through  the  legs. 

The  following  is  a  list  of  the  stores  required  for  it  when  hoist- 
ing a  15-inch  gun  to  the 'top  of  a  rampart  thirty  feet  high : 


DERRIOKF. 


289 


Material. 


Hemp  rope. 


Manila  rope...  • 


Hemp 

Iron..., 

Wood. 
Iron... 


Use. 


Main-tackle  fall .... 

Guys  (single  rope  doubled)... 
Straps  for  guys. 

Fore  guy - 

Lower-block  lashing 

Upper-block  lashing 

Loading-block  straps 

Muzzle- tackle  fall 

Guy-tackle  fall 

Preventer-tackle  fall 

Fore-guy- tackle  fall 

Luff-tackle  fall 

Muzzle-tackle  lashing 

Straps  for  various  uses 

Tratee-rope  for  lashing 

Shear-head  lashing 

Spun-yarn,  3-yarn 

Seizing  stuff.  12-yarn 

Stoppers  (soft  plated) 

Thimbles 

Sling-chains 

Handspikes  (mancsuvering).. 
Pinch-bars -. — 


No. 

Size. 

1Mb. 

1 

5.5 

1 

G 

2 

6 

1 

6 

1 

4.5 

2 

5 

4 

6 

1 

4.5 

2 

4 

2 

4 

1 

4 

1 

3.5 

2 

5 

8 

4 

3 

3 

1 

2.5 

6 

2.5 

« 

3 

3 

6 

2 

Len'th. 


Kfcthcma. 

90 

20 

10 

20 

20 

6 

2 

100 

20 

20 

30 

30 

8 

1  and  2 

5 

6 

iO 
5 

••••••••• 

••••••••• 

84  in. 
84  in. 


each,  i 


each, 
each. 

each, 
each. 


each.  ' 
each.  I 
each.  I 

I 


heavy, 
heavy. 


1 
1 
1 

Kind 

. 

i 

09 

0 

S 

2 
1 
2 
1 

4 

4 
2 
1 
2 
1 

i 

5 

0) 

A 
a 

*: 
© 

In. 

14 
14 
10 
10 

10 

8 
5 
5 
6 
4.5 

Material. 

1 

Purchase  blocks 

U8SD. 

• 

1 

• 
i— • 

o 

p 

• 

>—> 

• 

P. 

0 

u 

■§ 

0 

a? 

o 
a 

1 

2 

>  Wood  and  iron. 

Iron. 

Wood. 
f  2,  wooden. 
(2,  iron 

Iron. 

>  Wooden. 

1 

2 

l 

Muzzle  tackle,  leading- 
Guv  tackle,  leading...... 

1 

2 

2 
1 

2 
2 

1 

Fore-guy  tackle,  leading 

1 

1 
1 

1 

Two  capstans*  wooden  ;  four  stakes  for  securing  capstan,  8 

feet  long,  5  inches  diameter;  eight  stakes  for  securing  capstan, 
iy 


290  MACHINES   AND   APPLIANCES. 

6  feet  fong,  5  inches  diameter;  two  skids,  yellow  pine,  18  feet 
long  by  12  by  15  inches ;  fifteen  blocks,  yellow  pine,  assorted 
(four  sizes);  stakes  for  securing  sill,  8  feet  long,  5  inches  diameter. 

To  raise  a  lo-inch  gun. 

549*  The  derrick  is  put  together  on  top  of  the  rampart  (or 
other  place  to  which  the  gun  is  to  be  raised);  the  sill  is  about 
five  feet  from  the  edge  of  the  wall ;  the  main-tackle  upper  block 
is  lashed  to  the  cap  near  one  leg,  and  tlie  muzzle-tackle  upper 
block  near  the  other  leg. 

The  ends  of  the  guys  (Fig.  3,  Plate  51)  are  hitched  to  the  ends 
of  the  cap;  the  middle  laid  across  the  legs,  and  a  half  hitch 
taken  over  each  end,  thus  doubling  them ;  a  stout  thimble  is 
placed  in  the  bight  of  each,  into  which  the  guy  tackles  are 
hooked.  Secure  hold-fasts  must  be  obtained  for  the  guys;  to 
these  the  guy  straps  are  attached,  and  in  the  bight  of  each  a 
stout  thimble  is  placed,  into  which  the  guy  tackle  is  hooked. 

One  end  of  the  fore  guy  is  attached  to  the  middle  of  the  cap 
by  a  round  turn  and  two  half  hitches,  the  end  being  securely 
stoppered  to  the  guy. 

A  luff-tackle  purchase  is  applied  to  the  fore  guy  and  its  hold- 
fast, and  by  means  of  this  the  derrick  is  raised  to  a  vertical  posi- 
tion . 

The  sill  is  firmly  secured,  with  stakes  or  by  bracing  with  skids, 
against  some  fixed  object.  The  girtline  is  attached  to  the  cap 
by  a  strap,  and  having  been  raised  with  the  derrick,  a  man  is  sent 
up  by  it,  who,  by  the  same  means,  receives  the  leading  blocks, 
which  he  secures  to  the  cap  by  means  of  straps. 

The  main-tackle  fall  is  next,  rove  through  the  blocks,  and  the 
lower  block  lashed  to  the  gun  2  feet  6  inches  in  rear  of  the  axis 
of  the  trunnions.  The  muzzle-tackle  fall  is  rove,  and  the  lower 
block  lashed  3  feet  in  front  of  the  axis  of  the  trunnions.  These 
blocks  are  each  lashed  to  the  gun  by  seven  turns  with  the  lower- 
block  lashing,  the  lashing  being  f rapped  on  each  side  of  the 
blocks  with  its  ends. 

Two  snatch  blocks  are  attached  to  the  sill,  one  near  the  foot 
of  each  leg,  by  strong  straps.  These  straps  should  be  laid  on 
the  ground  under  the  sill  previous  to  raising  the  derrick,  and  if 
the  ground  is  gravelly  thejr  should  be  protected  from  chafing  by 
canvas  laid  under  them. 

Through  these  snatch  blocks  the  main  and  muzzle  tackle  falls 
are  severally  led,  each  to  one  of  the  capstans. 

The  capstans  are  manned  by  sixteen  men  each.  A  strain  is 
brought  upon  the  falls,  and  the  guy  tackles  hauled  upon  until 


DERRICKS.  291 

the  head  of  the  derrick  is  almost  vertically  over  the  edge  of  the 
wall. 

The  capstans  are  worked  and  the  gnn  is  hoisted,  care  being 
observed  to  work  the  capstans  so  as  to  keep  the  piece  in  a  hori- 
zontal position.  One  or  more  shifting-planks  are  let  down  by 
ropes  against  the  side  of  the  wall  to  prevent  the  gun  from  dialing 
against  it  and  to  ease  it  over  the  coping. 

When  the  gun  reaches  the  top  of  the  coping,  preventer  tackles 
are  hooked  to  straps  around  the  breech  and  muzzle.  When  the 
piece  is  sufficiently  high,  the  guy  luff  tackles  are  hauled  upon 
and  the  piece  landed  on  cribs  or  blocks.  The  preventer  tackles 
are  likewise  used  to  assist  in  bringing  in  the  piece  and  landing  it 
in  a  proper  position. 

If  it  is  desired  to  place  the  gun  on  the  cradle,  the  falls  are 
slacked  off  and  the  sill  of  the  derrick  moved  far  enough  back  to 
admit  the  cradle.  The  gun  is  again  raised  and  landedin  its  bed 
on  the  cradle. 

The  derrick  should  not  be  allowed  to  assume  an  Inclination  of 
less  than  four  upon  one. 

To  lower  a  15-inch  gun, 

550.  The  piece  is  brought  to  the  edge  of  the  wall  on  the 
cradle;  the  derrick  is  erected  over  it;  the  gun-sling  and  the 
tackling  attached,  all  in  the  manner  explained  for  hoisting;  the 
capstans  are  worked ;  the  piece  lifted  and  eased  to  near  the  edge 
of  the  wall  by  the  preventer  tackles.  The  cap  of  the  derrick 
having  been  placed  directly  over  the  piece,  the  strain  will  in- 
crease its  inclination  sufficiently  to  allow  the  gun  to  be  eased  to 
the  edge  of  the  wall.  In  this  position  the  piece  is  allowed  to 
rest  on  blocks  or  skids,  the  cradle  is  removed,  and  the  sill  of  the 
derrick  moved  up  close  to  the  gun. 

The  gi\n  is  then  hoisted,  eased  over  the  edge,  and  lowered  to 
the  foot  of  the  wall. 

The  derrick  is  dismantled  in  the  inverse  order  in  which  it  was 
put  up. 

Note. — One  capstan,  if  powerful  enough,  is  sufficient  for  low- 
ering or  hoisting  the  gun,  in  which  case  the  lower  block  is  lashed 
to  the  piece  at  the  centre  of  gravity.  The  lashing  is  executed  as 
before  explained. 

The  capstan  usually  issued  to  artillery  posts  is,  however,  not 
sufficiently  powerful,  and  it  will  invariably  require  two  of  them. 

Care  must  be  taken  to  keep  the  guys  hauled  upon  so  that  the 
cap  and  sill  remain  always  parallel  to  each  other;  the  derrick  is 
thus  prevented  from  twisting. 

By  omitting  the  cap  and  then  lashing  the  heads  of  the  spars 


292  MACHINES   AND    APPLIANCES. 

together  with  shear  lashing,  the  derrick  may  be  used  as  shears* 
Id  this  case,  only  the  main  tackle  can  be  used. 

When  spars  can  be  procured  of  sufficient  length  to  construct 
shears  high  enough,  it  is  best  to  place  the  shears  at  the  foot  of 
the  wall  instead  of  on  top.  The  shears  should  be  not  less  than 
20  feet  higher  than  the  wall.  This  method  permits  the  piece  to 
be  raised  and  eased  over  to  the  terre-plein  with  less  inclination, 
and  consequently  less  strain  upon  the  legs  of  the  shears  and  on 
the  guys. 


Qnxt  fourth. 


CARE  AND    PRESERVATION    OP  ARTILLERY 

MATERIAL. 

551.  All  cannon  and  other  artillery  material  are  either  man- 
ufactured or  purchased  by  the  Ordnance  Department  and  turned 
over  to  the  artillery  arm  for  use. 

It  is  the  duty  of  the  artillery  to  care  for  and  preserve  such 
property,  and  to  return  to  the  Ordnance  Department  for  repairs 
such  as  may  require  it. 

Officers  in  charge  of  permanent  works  will  keep,  as  far  as  pos- 
sible, the  armament  complete  and  in  serviceable  condition,  and 
will  also  keep  on  hand  a  proper  quantity  of  ammunition  and 
other  supplies. 

552*  A  book  is  furnished  to  each  post  for  the  "  record  of  artil- 
lery "  and  "record  of  firing  "  In  the  front  of  this  book  are  printed 
instructions  fully  explaining  how  it  is  to  be  kept.  Under  appro- 
priate headings,  in  the  part  set  aside  for  record  of  artillery,  each 
gun  is  described  by  its  number  and  marks;  when  received  and 
where  from ;  whether  mounted  or  dismounted ;  if  mounted,  in 
what  part  of  the  work,  stating  its  platform  number.  The  result 
of  each  inspection,  made  as  hereinafter  described,  will  be  entered 
for  each  piece  in  this  part  of  the  book. 

In  the  portion  of  the  book  devoted  to  record  of  firing,  each  piece 
has  a  separate  page,  which,  when  filled,  is  carried  on  to  another. 
Each  shot  tired  is  duly  recorded  as  to  date  of  fire,  kind  and 
weight  of  projectile,  kind  and  quantity  of  powder,  elevation, 
time  of  flight,  range,  &c.  When  a  piece  is  transferred  from  one 
post  to  another  a  complete  record  is  sent  with  it,  and  the  pre- 
vious number  of  fires  is  entered  in  the  book  at  the  last  post,  so 
that  the  firing  may  not  go  beyond  the  limit  prescribed  as  the 
endurance  of  the  piece;  this  has  been  fixed  at  one  thousand 
service  rounds  for  cast-irou  cannon. 

553*  Marks,  All  cannon  are  required  to  be  marked  with 
the  weight  in  pounds,  the  number  of  the  piece,  the  initials  of  the 
inspector's  name,  the  initials  or  name  of  the  foundry,  and  the 
year  of  fabrication.  All  pieces  manufactured  since  1861  have 
these  marks  on  the  face ;  those  of  previous  date  have  them  dis- 

(293) 


294  CARE   AND   PRESERVATION   OF 

tributed  on  the  ends  of  the  trunnions,  the  face,  the  breech,  and 
the  top. 

The  numbers  for  each  kind  and  calibre  at  each  foundry  are  in 
separate  series. 

Cannon  that  have  been  inspected  and  condemned  are  marked 
on  the  face  X  C. 

554.  Ordnance-sergeant.  The  ordnance-sergeant  of  a  post 
has,  under  the  commanding  officer,  immediate  charge  of  all  the 
artillery  material  at  the  post.  It  is  his  special  duty  to  see  to  its 
care  and  preservation,  and  to  keep  the  books  and  records  relat- 
ing thereto.  He  takes  an  account  of  receipts  and  expenditures, 
makes  a  memorandum  of  all  breakages  and  damages,  and  keeps 
the  commanding  officer  informed  as  to  the  condition  of  the 
armament  of  the  post  and  the  extent  of  the  supplies. 

555.  Preservation  of  artillery.  Cast-iron  cannon,  whether 
mounted  or  dismounted,  should  be  lacquered  once  a  year.  The 
lacquer  used  is  coal-tar  of  the  best  quality,  mixed  with  sufficient 
spirits  of  turpentine  to  make  it  work  freely  with  a  paint  brush. 
It  should  be  applied  only  in  warm  weather. 

The  muzzle  of  the  piece  should  always  be  depressed  so  that 
water  may  not  stand  in  the  bore,  the  tompion  kept  in,  and  the 
vent  closed.  At  least  once  a  month,  especially  after  a  rainy 
period,  the  bore  should  be  sponged  dry  and  oiled  by  passings 
down  it  a  sponge  saturated  with  sperm  oil ;  especial  attention  in 
this  respect  should  be  given  to  rifled  guns.  In  cold  weather  a  lit- 
tle kerosene  oil  is  mixed  with  the  sperm.  The  vent  at  the  same 
time  is  examined  and  oiled,  and  if  the  piece  is  not  in  use,  stopped 
with  putty  or  a  plug  of  soft  wood.  When  the  piece  is  mounted, 
the  trunnions  and  trunnion  beds  are  kept  from  rusting  by  pour- 
ing a  small  quantity  of  the  same  oil  into  the  beds  and  elevating 
and  depressing  it  several  times. 

Once  a  month  the  carnage  should  be  traversed  so  as  to  change 
its  place  of  rest  on  the  traverse  circle.  At  the  same  time  the 
pintle  and  axle  journals  are  oiled  with  sperm  oil,  and  pieces  with 
hydraulic  or  pneumatic  butlers  run  from  battery  and  the  pistons 
cleaned  and  oiled.  If  the  pistons  are  found  rusted,  the  rust  is 
removed  with  fine  emery-cloth,  and  the  surface  polished  smooth 
with  rotten-stone  and  oil.  Such  pieces  ought  always  to  be  kept 
in  battery  aud  the  air  holes  in  the  cylinder  heads  carefully  closed 
wih  the  plugs. 

The  axles  of  the  truok-wheels  are  cleaned  and  (Mired  for  in  the 
same  manner  as  the  pistons.  Elevating  screws,  when  not  in  use, 
are  kept  in  the  store-house,  and  are  cleaned  and  oiled  in  the  same 
way.  Guns,  especially  rifled  pieces,  in  batteries  exposed  to  blow- 
ing sand,  should,  in  addition  to  the  tompion,  be  provided  with 


ARTILLERY  MATERIAL.  295 

canvas  hoods  placed  over  the  muzzle.  When  firing,  this  is  a 
useful  precaution. 

Cannon  not  mounted  should  he  placed  together,  according  to 
kind  and  calibre,  on  skids  of  stone,  iron,  o;/  wood  laid  on  hard 
ground,  well  rammed  and  covered  with  a  layer  of  cinders  or 
gravel  to  prevent  vegetation.  The  pieces  should  rest  on  the  skids 
in  such  a  manner  as  to  be  rolled  over  when  necessary  for  lacquer- 
ing, the  muzzle  depressed  and  in  such  position  as  to  be  readily 
got  at  with  the  sponge.  The  place  selected  should  be  free  from 
shade  of  either  buildings  or  trees. 

Siege  mortars  may  be  placed  on  their  muzzles,  resting  on  thick 
planks  or  pavement. 

556.  Carriages.  Iron  carriages  should  be  painted  once  a  year, 
and  this  in  dry,  Warm  weather.  The  best  paint  for  preservation  of 
iron  is  red-lead,  but  this  being  comparatively  expensive,  the  kind 
generally  used  is  oriental  red  paint.  It  is  supplied  ready  mixed, 
and  is  applied  in  the  usual  manner  of  painting.  If  it  should  re- 
quire thinning  down,  this  i«  effected  by  adding  turpentine  and 
linseed  oil,  the  latter  either  boiled  or  raw. 

Before  painting,  all  blisters,  rust,  or  accumulation  of  old  paint 
should  be  removed  with  a  scraper.  The  top  of  the  chassis  rails 
should  neither  be  painted  nor  oiled,  but  kept  clean  by  dry  scrap- 
ing. All  iron  handspikes,  elevating-bars,  and  similar  imple- 
ments are  painted  black,  using  for  this  purpose  common  black 
paint.  Heads  of  bolts  and  edges  of  rails  may  likewise  be  painted 
blaek. 

The  damp  location  of  most  artillery  posts  is  particularly  favor- 
able to  the  rapid  decay  of  material.  Rust  gradually  eats  away 
iron  parts  of  carriages  and  machines.  These  defects  are  fre- 
quently hidden  by  repeated  coats  of  paint  or  lacquer,  making 
them  extremely  liable  to  lead  to  accident  or  disaster.  Such  parts 
should  be  carefully  examined  by  means  of  punches  and  ham- 
mers, and  no  such  material  be  suffered  to  remain  where  it  is 
dangerous. 

The  wooden  parts  of  gun  carriages  and  machines  frequently 
become  dry-rotted,  while  the  exterior,  covered  with  pain:,  con- 
tinues a  shell  apparently  quite  sound.  Sounding  such  parts  with 
a  hammer,  and  searching  into  cracks  and  flaws,  will  indicate  the 
defects. 

Wooden  implements  become  brittle  from  age,  by  having  the 
"life  seasoned  out."  This  is  readily  detected,  by  those  familiar 
with  wood,  by  the  appearance  of  the  fracture,  the  weight,  the 
elasticity,  and  by  the  resonance  of  the  article. 

557*  Siege-pieces  are  scraped  off  and  painted  once  a  year 
with  black  paint  or  Japan  varnish,  they  being  dismounted  for  this 


296  CARE   AND   PRESERVATION   OF 

purpose.  The  carriages  are  scraped  to  remove  all  blisters  and 
lumps  of  old  paint,  and  then  painted  with  olive  paint.  The  iron 
parts  are  painted  black. 

If  possible,  siege-gun  carriages  should  be  kept  under  cover  in 
well-ventilated  sheds. 

The  following  is  the  method  pursued  in  the  !N*avy  for  blacking 
and  polishing  guns.  Whenever  the  number  of  men  in  charge  of 
pieces  admits  of  it,  the  same  care  should  be  observed  in  the  land 
service. 

The  piece  is  first  scraped  clean  and  then  scrubbed  well  with 
fresh  water  and  sand  ;  when  dry  it  is  washed  with  spiiits  of  tur- 
pentine, and  a  coat  of  well-ground  red-lead,  mixed  with  boiled 
linseed  oil,  is  applied  ;  this  is  well  and  smoothlyrubbed  in,  allow- 
ed a  couple  of  days  to  harden,  and  then  rubbed  down  with  sand- 
paper, after  which  another  thin  coat  of  red-lead  and  oil  is  applied  ; 
this  is  allowed  to  dry,  and  is  then  rubbed  until  smooth.  A  coat 
of  well-mixed  and  strained  black  paint  is  now  applied,  as  smooth- 
ly as  possible,  and  allowed  to  dry,  after  which  a  polish  of  the  fol- 
lowing preparation  is  used,  viz.:  4  lbs.  of  good  bees-wax  and  1 
lb.  of  spermaceti  are  melted  together  in  a  clean  vessel  free  from 
grit;  while  hot  this  is  strained  through  a  cotton  or  woollen  cloth. 
To  this  mixture  is  added  1  oz.  of  dry  ground  Prussian  blue,  0.75 
lb.  of  ivory-black,  or  the  same  quantity  of  lamp-black,  and  1  gal- 
lon of  spirits  of  turpentine.  All  these  ingredients  are  mixed  well 
together  while  warm,  and  thoroughly  rubbed  in  with  the  hand; 
the  rubbing  is  finished  by  working  the  hand  around  the  piece — 
not  lengthwise.  The  first  coat  is  allowed  to  stand  a  da}r  and 
then  rubbed  lightly  with  a  cotton  cloth,  after  which  a  second 
coat  is  applied  and  rubbed  with  the  cloth  until  a  brilliant  polish 
results. 

In  case  the  mixture  is  not  put  on  smoothly,  it  may  be  neces- 
sary to  cork  the  surface  ;  this  is  done  by  rubbing  with  a  fiat  piece 
of  cork  about  half  the  size  of  the  hand.  Scratches  are  generally 
corked  out,  care  being  taken  to  avoid  all  dust  or  grit. 

To  brown  a  gun.  Scrape  clean  ;  scrub  with  fresh  water,  sand, 
and  canvas;  allow  to  dry;  wipe  off;  apply  a  strong  solution  of 
salt  and  vinegar  three  or  four  times  a  day  for  two  days,  or  until 
a  good  coat  of  rust  is  formed;  allow  to  dry,  then  rub  lightly  with 
old  canvas ;  apply  a  thin  coat  of  the  following  mixture,  rubbing 
it  in  well :  4  lbs.  bees-wax,  melted  and  strained;  0.50  oz.  pure 
vitriol  (white),  or  1  oz.  of  pulverized  alum  ;  1  gallon  spirits  of  tur- 
pentine ;  allow  to  dry  until  next  day ;  then  put  on  another  thin 
coat,  and  when  dry  rub  with  a  clean  cotton  cloth. 

In  case  of  a  dull  appearance,  by  reason  of  having  been  handled, 


ARTILLERY   MATERIAL.  297 

nib  over  with  a  cot  to  u  cloth  aud  spirits  of  turpentine,  and  then 
with  a  thy  cloth. 

558.  Injuries,  The  injuries  to  which  heavy  cannon  are 
liable  are  confined  almost  entirely  to  the  interior.  Rusting 
produces  roughness  and  an  enlargement  of  the  bore,  and  in- 
creases any  cavities  or  honey-combs  that  exist  in  the  metal . 

In  smooth-bore  guns,  the  principal  injuries  arise  from  the  wear- 
ing away  of  the  metal  on  the  upper  and  lower  surfaces  of  the 
bore  at  the  seat  of  the  projectile  aud  the  enlargement  of  the  in- 
terior orifice  of  the  vent.  This  enlargement  of  the  bore  can  be 
measured  with  accuracy  only  by  means  of  the  star  gauge ;  but 
as  this  instrument  is  seldom  to  be  had  at  artillery  posts,  reliance 
must  be  placed  upon  such  inspection  as  can  be  made  with  a 
mirror  or  small  lamp.  When  the  enlargement  is  sufficiently 
great  to  be  manifest  by  such  inspection,  the  piece  should  not 
be  further  used  until  it  can  be  gauged  and  the  full  extent  of  the 
injury  determined. 

The  enlargement  of  the  vent  is  determined  by  means  of  an 
impression  of  it  taken  with  wax  or  soft  gutta-percha,  applied  by 
pressing  it  up  against  the  bore  at  the  vent  as  hereinafter  de- 
scribed. The  appearance  of  a  vent  {Fig,  4)  enlarged  by  much 
firing  is  irregular  and  angular,  with  its  greatest  diameter  in  the 
direction  of  the  axis  of  the  bore.  When  the  fissures  of  this  en- 
largement exceed  an  inch  in  any  direction,  the  piece  is  no  longer 
serviceable,  and  further  use  of  it  should  be  discontinued  until  a 
new  vent  can  be  bored  aud  the  old  one  stopped  with  melted  zinc. 
One  vent  in  a  cast-iron  piece  will  stand  five  hundred  service 
rounds.  Other  enlargements,  or  cracks  in  the  vent,  may  be  dis- 
covered by  means  of  a  searcher  made  of  a  piece  of  bent  Wire. 
The  service  to  which  a  cast-iron  piece  has  been  subjected  can 
generally  be  approximately  determined  by  the  appearance  of  the 
vent. 

All  cracks  and  flaws,  in  any  part  of  the  piece,  should  cause 
it  to  be  laid  aside  until  it  can  be  inspected  with  the  proper  in- 
struments. 

Rifle  cannon.  These  become  injured  by  the  wearing  away  of 
the  lands,  especially  upon  the  driving  side. 

Any  serious  damage  to  the  lands  can  be  ascertained  by  exam- 
ining the  bore  with  a  mirror.  It  will  also  manifest  itself  in 
firing  by  inaccuracy  and  frequent  tumbling  of  the  projectiles. 

Slight  cracks  in  the  surface  of  the  bore,  particularly  about  the 
seat  of  the  charge,  indicate  the  approaching  fracture  of  a  piece, 
and  should  be  sufficient  warning  to  cause  a  discontinuance  of  its 
use. 

The  bursting  of  shells  in  the  bore,  particularly  in  rifled  pieces, 


298  CARB   AND   PRESERVATION    OF   MATERIAL. 

frequently  causes  dents  and  abrasions.  Such  burstings  or  pre- 
mature explosions  are,  however,  less  frequent  now  than  formerly, 
owing  probably  to  the  fact  that  milder  and  slower  powders  are 
now  used  behind  the  projectile ;  still,  such  accidents  occasionally 
take  place,  and  the  causes  which  lead  to  their  occurrence  are  often 
obscure  and  require  close  investigation  to  discover. 

Most  prominent  among  those  usually  assigned  are  the  follow- 
ing :  Too  great  quickness  of  burning  in  the  powder  charge  of  the 
gun  ;  defects  in  the  working  or  placing  of  the  fuses ;  imperfec- 
tions in  the  metal  of  the  shells  themselves,  due  to  faulty  casting: 
thinness  of  the  walls  or  of  the  butt;  concussion  and  friction  of 
the  powder  within  the  shell  itself  when  the  piece  is  fired;  insuf- 
ficient quantity  of  powder  in  the  shell. 

Most  of  these  causes  take  effect  at  the  instant  of  ignition  of 
the  powder  charge  of  the  gun,  and  it  is  probable  that  most  shells 
that  fail  receive  their  injuries  before  they  are  unseated,  or  their 
inertia  fully  overcome. 

It  has  been  found  that  roughness  on  the'  interior  of  shells  or 
the  presence  of  grit  contributes  to  the  frequency  of  premature 
explosions,  by  shock  and  attrition  with  the  grains  of  the  burst- 
ing charge;  hence  it  is  important  to  remove,  by  scraping,  all 
such  gritty  substances.  It  is  recommended  to  coat  the  interior 
of  shells  with  some  elastic  composition.  A  very  good  kind  is  com- 
posed of :  Soap,  (common  yellow,)  1G  ounces;  tallow,  7  ounces; 
rosin,  7  ounces.  The  tallow  should  be  melted  first;  then  melt 
and  add  the  rosin,  and  lasrly  the  soap,  bringing  the  mass  to  a 
heat  that  will  make  it  very  fluid. 

The  shells  having  been  first  thoroughly  cleaned,  fill  them 
about  one-third  full  of  the  composition,  roll  them  slowly  so  as 
to  spread  the  mixture  over  the  whole  interior  surface,  and  then 
pour  off  the  residue.  This  coating  should  be  about  one-tenth 
(0.1)  of  an  inch  in  thickness,  except  at  the  bottom  of  the  shell, 
where  it  should  be  about  three-qimrters  of  an  inch  thick.  To 
obtain  these  thicknesses,  the  operation  of  coating  should  be  per- 
formed twice ;  then  pour  into  the  shell  enough  of  the  composi- 
tion to  produce  the  desired  thickness  at  the  bottom,  the  shell 
standing  on  its  base.  After  the  composition  is  perfectly  cool, 
immerse  tin*  shell  in  hot  water  at  as  high  a  temperature  as  the 
composition  will  stand  without  u running" — about  170  degrees. 
This  second  heating  of  the  composition  in  the  bath  toughens  it, 
and  causes  it  to  adhere  more  closely  to  the  shell. 

Another  method  of  meeting  this  difficulty,  as  also  that  arising 
from  friction  and  packing  from  the  set-back  of  the  grains  of  the 
bursting  charge,  is  to  place  the  charge  in  a  bag.  The  material 
for  the  bags  is  the  same  as  for  cartridges;  they  are  made  in  the 


INSPECTION   OF   CANNON.  29J> 

same  way,  and  of  a  size  suitable  for  the  charge.  In  charging  a> 
shell  in  this  manner,  the  bag  is  pushed  into  the  eavity  with  a 
slender  stick,  leaving  the  mouth  of  the  bag  projecting  out  of  the 
fuse  hole ;  this  is  securely  held  while  the  powder  is  introduced 
through  a  funnel,  and  worked  and  settled  into  the  bag  with  the 
stick.  When  the  bag  is  nearly  full  the  funnel  is  withdrawn,  the 
neck  of  the  bag  tied,  and  pushed  down  to  one  side  of  the  fuse 
hole. 

On  the  occurrence  of  a  premature  explosion,  or  the  rupture  of 
a  shell  in  a  gun,  the  bore  must  be  carefully  examined  with  the 
mirror,  and  by  taking  impressions,  especially  about  the  place  of 
explosion.  A  close  examination  should  be  made  for  cracks* 
These  may  not  at  first  be  discoverable,  but  will  develop  with 
subsequent  firings.  It  is  important,  therefore,  that  frequent  ex- 
aminations be  made  of  guns  in  which  shells  have  exploded. 

Inspection  of  cannon. 

559.  Every  artilleryman  should  know  how  to  examine  the 
weapon  with  which  he  works,  and  should  understand  what  de- 
fects in  guns  are  serious  and  what  may  be  disregarded.  It  is  of 
great  importance  that  the  examination  of  both  guns  and  fittings 
should  be  very  searching  and  exaet ;  otherwise,  a  small  flaw  left 
unnoticed  may  endanger  the  life  of  the  piece  in  future. 

Guns,  upon  being  accepted  into  service,  are  inspected  as  pre- 
scribed in  the  regulations  for  the  Ordnance  Department. 

The  following  rules  are  given  for  subsequent  inspections  in 
service. 

Every  gun  must  be  examined  after  firing  the  following  num- 
ber of  rounds  with  projectiles : 

Smooth-bore  cast-iron  guns. — Firing  50-lb  charges  and  upwards,. 
50;  10-tt)  up  to  50-Bb  charges,  100;  under  10-tt>  charge,  200. 

Rifles. — 10-inch  and  upward,  50;  8-inch,  100;  under  8-inch,, 
150. 

In  the  record-book  of  tiring,  (see  par.  552,)  on  the  pages  where 
the  shots  are  recorded  should  be  entered  the  inspections,  their 
dates,  by  whom  made,  and  a  full  description  of  any  defects  that 
may  be  found,  and  particularly  whether  those  discovered  at  pre- 
vious examinations  are  increasing,  and  if  so,  to  what  extent. 

Instruments  for  inspecting  cannon. 

560.  1.  Star-gauge.  Used  for  measuring  the  diameter  of 
the  bore  at  any  point. 

2.  Cylinder-staff.  Used  to  measure  the  length  of  the  bore. 
It  is  supported  in  the  centre  of  the  muzzle  by  a  T-rest,  and  the- 


300  INSPECTION    OF   CANNON. 

■extremity  inserted  in  the  gun  is  furnished  with  a  measuring 
point  and  guide  plate. 

3.  Cylinder- gauge.  This  is  a  hollow  cylinder  of  cast-iron, 
turned  to  the  least  allowed  diameter  of  the  bore,  and  one  calibre 
in  length.    When  used,  it  is  attached  to  the  cylinder-staff. 

4.  Searcher*  consisting  of  four  flat  springs  turned  up  into 
points  at  their  ends,  and  attached  to  a  socket  which  is  screwed 
■on  the  end  of  the  cylinder-staff.  It  is  used  to  feel  for  cavities 
in  the  surface  of  the  bore. 

5.  Trunnion-gauge.  Used  to  verify  the  diameter  of  the  trun- 
nions and  rimbases. 

6.  Trunnion-square.  Used  for  verifying  the  position,  of  the 
trunnions  with  reference  to  the  bore. 

7.  Trunnion-rule*  for  measuring  the  distance  of  the  trunnions 
■from  the  bast;  of  the  breech. 

8.  Calipers*  for  measuring  exterior  diameters. 

9.  Standard  rule*  for  veriifying  other  instruments. 

10.  Vent-gauges  of  steel  wire,  with  shoulders  to  prevent  them 
from  slipping  into  the  vent.  There  arc  three,  differing  in  size 
by  0.005  of  an  inch;  one  is  the  exact  size  of  the  vent,  and  one 
larger  and  one  smaller  than  the  exact  size.  To  ascertain  the 
wear  of  a  vent  there  should  be  several  others,  increasing  in  size 
Tty'the  above  dimensions. 

11.  Vent-searcher  is  a  steel  wire  of  the  length  of  the  vent,  bent 
to  a  right  angle  at  the  lower  end  and  pointed.  It  is  used  to  de- 
tect cavities  in  the  sides  of  the  vent. 

12.  Wooden  rule*  to  measure  exterior  lengths. 

13.  Mirror*  for  reflecting  the  sun's  rays  into  the  bore. 

14.  Spirit  lamp*  attached  to  a  staff,  used  in  examining  the  bore 
when  the  mirror  cannot  be  used. 

15.  Machine  for  taking  impressions  of  the  bore. 

561.  To  ascertain  injuries  to  cannon  in  service,  only  those  of 
the  foregoing  list  numbered  1,  2,  4,  10,  11,  13,  14,  and  15  are 
required. 

The  star-gauge  (Fig.  1,  Plate  54)  is  composed  of  the  staff,  the 
■handle,  and  a  set  of  four  steel  points  for  eacli  calibre. 

The  staff  is  a  brass  tube,  made  in  three  pieces,  for  convenience 
-of  stowage,  and  connected  together,  when  required,  by  screws. 
The  end  that  goes  into  the  gun  expands  into  a  head  (a),  in 
which  are  placed  four  steel  sockets,  at  equal  distance  from  each 
-other,  which  receive  the  points.  Two  of  the  sockets  opposite 
-each  other  are  secured  permanently ;  the  other  two  are  movable. 
A  taperng  plate  or  wedge  (6),  the  sides  of  which  are  cylindrical, 
runs  through  a  slot  in  the  head;  an  aperture  in  the  inner  ends 
•of  the  movable  sockets  embraces  the  cylinder,  so  that  when  the 


INSPECTION    OF   CANNON.  301 

wedge  is  moved  forward  the;  sockets  are  forced  outwards,  and 
when  moved  backwards  the  socket 4  are  withdrawn.  Tlie  <ide» 
of  the  wedge  in-line  0.35  inch  in  a  length  of  %22  inches,  so  that  by 
pushing  the  slide  in  the  thirty-fifth  pan  of  this  distance,  the  dis- 
tance between  the  two  sockets  is  increa>ed  0.01  in«  h. 

A  square  sliding  rod  (c)  is  connected  with  the.  wedge,  and  runs 
through  the  whole  length  of  the;  tube,  projecting  a  few  inches 
beyond  the  outer  end.  This  rod  is  in  Ihree  parts,  like  the  staff, 
and,  like  them,  connects  by  screws.  The  sections  of  the  rod  are 
prevented  from  falling  out  of  their  proper  section  of  the  staff  by 
pins.  When  screwing  the  joints  of  the  stall'  together,  if  the  end* 
of  the  rod  are  pressed  up  to  each  other  they  become  connected 
by  the  same  motion. 

The  staff  is  graduated  Into  inches  and  quarters,  so  that  the 
distance  of  the  point  from  the  muzzle  of  the  piece  may  always 
be  known. 

The  handle  {Fig.  2,  Plate  54)  is  made  to  fit  over  the  outer  end 
of  the  staff',  and  to  connect  with  the  sliding  rod  by  a  screw  hav- 
ing a  milled  head  at  the  outer  extremity  of  the  handle.  It  may 
be  used  on  either  joint,  as  most  convenient  for  the  length  of  the 
bore.  The  socket  of  the  handle  slips  over  the  end  of  the  staff 
made  smaller  for  the  purpose,  and  has  a  slot  in  it,  allowing  the 
staff  to  be  seen  through  it.  A  scale  on  one.  side  of  the  slot  is 
graduated  to  show  the  distance  that  the  rod  moves  to  throw  the 
points  0.01  apart. 

That  part  of  the  handle  containing  the  slot  and  scale  is  sepa- 
rated from  the  other  part,  but  is  made  to  fit  closely  over  it.  On 
one  side  there  is  a  mill-headed  screw  for  clamping  the  parts  to- 
gether. Seen  through  the  slot  is  a  small  plate  of  silver  inserted 
in  the  staff,  and  a  fine  mark  upon  it  to  show  the  place  of  the 
zero  when  the  points  are  adjusted.  The  zero  mark  on  the 
scale  is  made  to  correspond  with  it  by  means  of  the  screw  just 
mentioned. 

A  set  of  adjusting  rings  belongs  to  the  instrument — one  for 
each  calibre — reamed  out  to  the  exact  minimum  diameter  of  the 
bore.  To  adjust  the  gauge  for  anjT  calibre,  the  handle  is  loosened 
by  means  of  the  clamp  screw,  the  proper  measuring  points  are 
screwed  in,  the  adjusting  ring  placed  over  them,  and  the  slider 
pushed  out  until  all  the  points  touch  the  inner  circumference. 
The  zero  of  the  scale  is  then  made  to  coincide  with  the  mark  on 
the  tube,  and  the  handle  clamped;  the  instrument  is  then  ready 
for  use. 

The  arms  of  the  T-rest  (Fig.  3,  Plate  54)  are  adjusted  for  the 
particular  calibre.  It  is  placed  in  the  muzzle  to  keep  the  instru- 
ment in  the  axis  of  the  piece.    A  centre  line,  starting  from  the 


302  INSPECTION   OF  CANNON. 

■centre  of  one  of  the  permanent  sockets,  is  marked  on  the  staff 
throughout  its  length.  In  joining  the  sections  together  care 
•must  be  taken  to  secure  coincidence  of  this  centre  line.  When 
the  gauge  is  in  the  bore  the  centre  line  should  be  uppermost; 
the  movable  points  are  then  horizontal,  and  measure  the  diam- 
eter of  the  bore  only  in  a  horizontal  plane.  To  make  a  thorough 
measurement  in  every  direction,  the  piece  should  be  on  skids, 
and  then  by  rolling  it  over  different  elements  of  the  bore  will  be 
brought  uppermost,  and  can  be  measured  in  succession.  When 
the  piece  cannot  be  rolled  over,  and  it  is  desirable  to  obtain 
measurements  all  round  at  any  part  of  the  bore,  the  gauge  may 
be  inserted  with  the  movable  points  in  the  direction  in  which  it 
is  required  to  make  the  measurement.  The  centre  line  of  the 
staff*  will  indicate  the  direetion  of  the  measuring  points. 

To  ascertain  thoroughly  the  condition  of  the  bore,  measure- 
ments should  be  made  at  intervals  of  0.25  inch  in  the  part  occu- 
pied by  the  charge  and  shot;  at  intervals  of  one  inch  in  the  rest 
of  the  bore  in  rear  of  the  trunnions,  and  at  about  one  calibre 
intervals  from  the  trunnions  to  the  muzzle. 

In  the  original  inspection  of  the  piece,  no  variation  greater 
than  0.03  inch  beyond  the  true  dimensions  was  allowed;  there- 
fore anything  exceeding  this  is  an  enlargement  caused  by  serv- 
ice. The  scale  upon  the  handle  of  the  instrument  is  marked  to 
-correspond  to  hundredths  of  an  inch  of  movement  of  the  meas- 
uring points.  The  divisions  are  numbered  both  ways  from  the 
zero.  Those  towards  the  handle  indicate  excess  of  diameter; 
those  in  the  other  direction  indicate  deficiency.  Rifled  pieces 
are  measured  across  from  the  lands — not  from  the  grooves.  In 
doing  this,  a  special  instrument  is  required  for  guiding  the  meas- 
uring points  so  that  they  will  follow  the  lands  as  they  proceed 
.along  the  bore.  The  hexagonal  hole  {Fig.  4)  in  the  centre  is 
fitted  on  to  that  portion  of  the  end  of  one  of  the  measuring 
points  which  is  similarly  shaped.  Two  small  arms  on  either  side 
of  the  guide-piece  face  each  other,  and  can  be  moved  toward  or 
from  each  other  by  means  of  sliding  plates  to  which  they  are 
attached.  For  this  adjustment,  finely-divided  scales  are  marked 
on  the  sliding  plates.  When  iu  the  bore  the  two  small  arms 
rest  in  two  contiguous  grooves,  and  embrace  between  them  the 
land  which  the  measuring  point  is  forced  to  follow. 

To  prevent  obsiructiug  the  motion  of  the  measuring  point 
when  it  is  shoved  out  by  the  slider,  the  arms  rest  upon  light 
springs,  which  are  simply  compressed  during  the  measurement. 

The  hexagonal  socket  is  made  to  turn  within  the  rest  of  the 
guide-piece  to  allow  the  necessary  freedom  to  the  arms. 

Before  and  after  each  set  of  measurements,  the  rings  must  be 
applied  to  the  points  and  the  instrument  adjusted. 


IMPRESSIONS   OF   THE   BORE.  303 


Instruments  for  taking  impressions. 

562*  The  machine  (Fig.  1,  Plate  55)  for  taking  the  interior 
impression  of  the  vent  consists  of  a  wooden  head  (a),  one-half 
the  length  of  which  is  cylindrical  and  the  other  half  rounded  off 
to  the  shape  of  the  bottom  of  the  bore.  The  diameter  of  the 
head  is  rather  smaller  than  the  bore.  A  staff  (6),  flat  on  the 
upper  side  and  rounded  on  its  under  side  to  fit  the  curve  of  the 
bore,  is  mortised  into  the  cylindrical  part  of  the  head  so  that  the 
rounded  side  will  be  coincident  with  the  circumference.  A  mor- 
tise (c)  is  cut  through  the  head,  extending  several  inches  in  rear 
and  front  of  the  position  of  the  vent.  Into  this  mortise  a  loose 
block  is  fitted,  capable  of  free  upward  and  downward  motion. 
The  top  of  the  block  is  pierced  with  holes  to  secure  the  compo- 
sition spread  over  its  surface.  This  movable  piece  rests  on  a 
wedge  (d)  attached  to  a  flat  rod  running  through  a  slot  in  the 
bead.  To  prevent  this  rod  and  the  wedge  from  coming  entirely 
out  of  the  head,  a  slot,  about  four  inches  long,  is  cut  iu  it, 
through  which  passes  a  pin  (e)  attached  to  the  staff. 

To  use  the  instrument,  withdraw  the  rod  as  far  as  the  slot 
will  permit ;  this  allows  the  block  to  drop  below  the  surface  of 
the  head,  and  protects  the  composition  which  has  been  spread 
on  it ;  push  the  head  to  the  bottom  of  the  chamber,  and  arrange 
the  position  of  the  staff  so  that  the  movable  piece  will  cover  the 
vent;  then  press  the  end  of  the  rod  home.  This  motion  will 
throw  out  the  block  with  the  composition,  and  a  distinct  impres- 
sion of  the  vent  and  of  fire-cracks  (should  there  be  any)  will  be 
left  upon  its  surface ;  draw  the  rod  back  as  far  as  the  slot  will 
allow,  and  withdraw  the  instrument;  the  impression,  being  pro- 
tected thereby,  will  come  out  uninjured. 

Gutta-percha  impressions  of  a  portion  of  the  bore  of  a  gun  can 
be  taken  by  means  of  wooden  blocks  or  wedges.  For  this  pur- 
pose use  two  blocks  (a  6,  Fig.  2,  Plate  55),  one  about  two- 
thirds  the  length  of  the  other,  the  longer  block  to  carry  the 
gutta-percha  for  the  impression,  the  shorter  one  to  be  driven 
as  the  wedge,  each  block  with  a  staff  or  handle  longer  than  the 
bore  of  the  gun,  so  as  to  enable  the  operator  at  the  muzzle  to 
place  the  blocks  in  any  desired  position  in  the  bore;  also  for 
driving  the  wedge  and  withdrawing  the  blocks.  These  blocks 
are  so  shaped  that  when  in  one  position  they  form  an  imperfect 
cylinder,  whose  diameter  is  less  than  that  of  the  bore,  thus  en- 
abling the  longer  block  to  carry  the  gutta-percha  to  the  required 
place  in  the  bore;  then,  by  driving  the  wedge,  the  diameter  of 
this  cylinder  is  increased  nearly  to  that  of  the  bore,  the  gutta- 
percha is  caught  between  the  surface  of  the  bore  and  its  carry- 


304  IMPRESSIONS   OF   THE   BORE. 

ing  block,  and  is  thus  forced  by  the  driven  wedge  to  take  note  of 
whatever  it  finds  there. 

To  take  an  impression,  the  gun  should  be  thoroughly  washed 
out  and  then  oiled  with  an  oiled  sponge;  the  gutta-percha  is 
softened  by  means  of  hot  water,  just  under  the  boiling  point, 
to  the  required  consistency,  about  that  of  putty;  is  then  placed 
on  the  block,  which  is  well  oiled  (sperm  oil  is  the  best),  and 
worked  and  kneaded  with  oil  until  it  is  spread  over  the  required 
portion  of  the  block;  the  blocks  are  well  oiled,  particularly  the 
surfaces  which  come  in  contact ;  the  two  blocks  are  put  together 
at  the  muzzle  so  as  to  enable  the  carrying  block  to  carr3r  the 
gutta-percha  to  the  desired  place ;  when  both  blocks  together 
are  pushed  into  the  bore,  the  distance  may  be  marked  on  the 
handle  of  the  carrying  block ;  the  carrying  block  is  then  held 
steady  by  its  handle,  while  the  wedge  block  is  driven  in  by  sev- 
eral blows  of  a  sledge  on  the  end  of  its  handle ;  from  two  to 
five  minutes  is  sufficient  time  to  allow  it  to  set.  The  wedge- 
block  is  withdrawn  first,  and  the  carrying  block  with  the  impres- 
sion afterwards.  To  withdraw  the  wedge  block,  run  an  iron 
pin  through  the  handle  near  the  end,  and  strike  against  that 
with  a  sledge  until  it  starts,  when  it  is  easily  withdrawn ;  the 
carrying  block  will  generally  fall  or  release  itself  by  its  own 
weight,  bringing  the  impression  with  it.  If  the  impression  is 
taken  anywhere  in  the  upper  half  of  the  bore,  and  for  this 
reason,  and  also  that  it  is  easier  to  work  the  blocks,  it  is  always 
better  to  turn  the  gun  over,  so  as  to  take  the  impression  above 
the  block.  When  this  cannot  be  done,  and  an  impression  is 
wanted  from  the  bottom  of  the  bore,  a  small  block  or  rider  is 
pushed  in  at  the  same  time  as  the  carrying  block,  so  as  to  keep 
the  gutta-percha  from  touching  the  surface  of  the  bore  while 
being  pushed  into  place.  Afterwards  the  rider  block  is  with- 
drawn, the  wedge  driven,  and  after  the  wedge  is  withdrawn  the 
rider  block  is  pushed  back  close  to  the  currying  block,  and  acts 
as  a  fulcrum  by  which  the  impression  is  raised  free  from  the 
bore,  when  both  are  withdrawn  together.  In  taking  an  impres- 
sion on  the  side,  it  is  better  to  push  in  the  blocks  as  if  the  im- 
pression was  above,  and  then  to  turn  the  blocks  to  the  place. 
Unless  the  block  under  the  gutta-percha  is  well  oiled,  some  diffi- 
culty may  be  experienced  in  releasing  the  impression  from  the 
block.  The  carrying  block  should  have  a  slight  raised  edge  on 
each  side  of  the  upper  surface  to  prevent  the  gutta-percha  from 
spreading  out  too  much  when  undergoing  the  pressure  from  the 
wedge,  and  also  to  protect  it  when  turning  the  blocks  for  side 
impressions. 

In  cases  where  there  is  any  doubt  as  to  the  state  of  the  bore 


IMPRESSIONS    OF   THE   BORE.  305 

of  rifled  guns,  impressions  should  bo  taken  of  the  whole  length 
with  gutta-percha,  and  for  doing  this  the  blocks  just  described 
shot ild  be  long  enough  to  reach  from  the  bottom  of  the  bore  to 
a  foot  or  more  beyond  the  muzzle.  They  are,  in  fact,  scantling 
rounded  off*  and  made  wedge-shape. 

A  convenient  size  to  obtain  the  gutta-percha,  is  in  slabs  twenty 
inches  long,  five  wide,  and  five-eighths  thick.  Each  slab  will 
make  ordinarily  two  or  three  impressions.  It  can  be  used  over 
and  over  .again,  and  need  never  be  thrown  away  if  a  little  fresh 
materia]  be  added  occasionally  to  prevent  it  from  becoming  brit- 
tle. It  must  be  kept  free  from  dust  or  grit,  and  should  be  pre- 
served in  water  when  not  in  use. 

As  a  proper  set  of  instruments  is  rarely  or  never  to  be  obtained 
at  artillery  posts,  a  substitute  for  taking  impressions  with  the 
wax  composition  may  be  made  by  using  a  block  of  wood  about 
a  foot  in  length,  one  side  of  which  is  rounded  oft"  so  as  to  have 
the  curvature  of  the  bore ;  to  the  block  is  attached  a  strong  staff 
or  handle.  To  use  it,  a  biscuit-shaped  ball  of  the  composition  is 
placed  on  the  rounded  surface  of  the  block,  which  is  then  in- 
serted to  the  flaw  and  pressed  against  the  bore,  using  chocks 
inside  the  gun  as  a  fulcrum  and  the  handle  as  a  lever. 

Impressions  of  the  vent  may  also  be  taken  with  lead.  The 
implements  required  for  this  are  a  piece  of  soft  fine  wire,  about 
twice  the  length  of  the  piece ;  a  stout  lever,  about  the  same 
length,  and  shod  to  suit  the  curve  of  the  bore;  and  a  small  but- 
ton of  soft  lead,  judged  to  be  of  sufficient  size  to  fill  the  vent  at 
least  one  inch  from  the  bore.  This  is  pierced  lengthwise  to  re- 
ceive the  wire. 

To  take  the  impression.  Shove  the  wire  through  the  vent ; 
let  it  pass  along  the  bore  and  out  at  the  muzzle ;  put  it  through 
the  leaden  button  and  tie  a  knot  at  the  end;  draw  the  wire 
back  through  the  vent  until  the  button  is  introduced  firmly  into 
the  inner  orifice ;  apply  the  lever,  making  its  shoe  bear  on  the 
button,  and  force  it  well  in  by  repeated  blows,  the  muzzle  being 
the  fulcrum,  or,  better,  a  block  of  wood  placed  in  the  bore  as  far 
as  the  arm  will  reach.  The  button  is  disengaged  by  pushing  in 
the  vent-punch. 

In  taking  impressions  of  the  vent  and  cracks,  each  button  in 
turn  is  used  as  a  pattern  for  moulding  its  successor. 

All  impressions,  however  they  may  be  taken,  should  be  most 
critically  examined  with  a  magnifying  glass;  otherwise  the  most 
important  indications  will  escape  observation. 

Water-proof,  Cannon,  when  inspected  upon  being  received 
into  service,  are  subjected  to  an  hjrdranlic  proof  of  about  30 
pounds  to  the  square  inch.     This  requires  a  special  apparatus 

20 


306         MODE  OF  EXAMINING  CANNON. 

not  usually  found  at  posts.  Nevertheless,  useful  application  of 
the  principle  may  be  made  by  giving1  the  piece  as  much  elevation 
as  possible,  stopping  the  vent,  and  tilling  it  with  water.  Allow 
it  to  stand  thus  for  a  few  hours,  draw  off  the  water,  wipe  the 
bore  perfectly  dry,  and  examine  writh  a  mirror  or  lamp.  Water 
S'en  oozing  from  any  part  of  the  bore  indicates  a  crack  or  a  clus- 
ter of  cavities,  a  sure  sign  of  serious  defects. 

563*  Mode  of  examination.  The  bore  should  be  thoroughly 
cleaned  to  detect  small  defects.  If  care  has  previously  been 
taken  in  keeping  a  gun  tolerably  clean,  it  will  probably  be  suffi- 
ciently prepared  for  examination  by  washing  and  drying  with 
tow,  cotton-waste,  or  a  clean  sponge.  Should  there  be  hard  rust 
which  will  not  yield,  or  a  thick  coating  of  grease,  the  bore  may 
be  cleaned  by  firing  (if  circumstances  permit  of  it)  one  or  two 
.scaling  charges  of  about  one-third  the  full  service  charge,  with- 
out projectiles;  this  will  usually  loosen  the  scale.  The  same 
may  be  effected  by  using  hot  water  and  potash,  in  the  following 
manner :  About  a  gallon  of  boiling  water  is  poured  on  one  pound 
of  ordinary  black  potash,  and  an  old  sponge,  covered  with  a 
cloth  to  make  it  fit  tightly  to  the  bore,  is  dipped  into  the  solu- 
tion, and  the  bore  rubbed  with  it  till  the  dirt  is  loosened,  when 
a  hard  brush  will  remove  it ;  it  is  then  wiped  dry  and  slightly 
oiled.  The  potash  water  must  be  used  very  hot  and  the  sponge 
made  to  fit  tightly,  or  the  process  is  ineffectual.  The  hard  brush 
is  made  of  wire,  and  is  similar  to  those  used  for  fowling-pieces. 
Brushes  of  bristles  —  Turk's-heads — are  also  used.  No  sharp- 
edged  or  pointed  scrapers  should  be  employed  for  cleaning  the 
bores  of  rifled  guns,  as  they  would  be  liable  to  injure  the  rifling. 

The  bore,  being  thus  cleaned,  should  be  examined  by  the  aid 
of  a  lamp,  or  if  there  be  bright  sunlight,  with  a  mirror.  If  the 
bore  be  slightly  wet,  the  detection  of  defects  is  greatly  facili- 
tated. A  sharp-pointed  pricker  is  used  to  ascertain  the  extent 
and  position  of  any  flaw,  the  staff  being  graduated  in  inches  so 
that  the  distance  from  the  muzzle  may  be  readily  ascertained. 
A  spring  searcher  is  also  used  to  detect  defects,  and,  with  rifles, 
in  such  manner  that  each  groove  shall  be  traversed  in  succession 
by  one  of  the  points. 

Should  a  flaw  be  found,  an  impression  is  taken  of  it.  This  is 
done  in  the  manner  just  described,  with  gutta-percha,  or  by 
using  a  mixture  composed  of  bees-wax,  two  parts;  treacle,  one 
part;  soft  soap*  one  part.  The  wax  should  be  melted  over  a 
slow  fire  in  an  iron  pot;  the  treacle  is  then  added  and  mixed 
well  by  stirring;  and  lastly  the  soft  soap,  a  little  at  a  time. 
The  mixture  must  be  kept  in  motion,  and  when  thoroughly 
stirred  poured  out,  cooled,  and  made  into  balls.    This  compo- 


MODE  OF  EXAMINING  CANNON.         307 

•sition  being  soft,  is  always  ready  for  use,  but  the  impression  i* 
easily  destroyed  by  handling. 

The  gun  should  be  so  placed  that  the  impression  will  be  taken 
upwards. 

In  recording  the  position  of  any  defect,  its  distance  from  the 
muzzle  is  given  in  inches,  aud  noted  as  "up,"  "right  of  up," 
"right  of  down,"  &c,  the  vent  always  being  considered  up,  aud 
the  right  or  left  the  sides  as  they  would  appear  to  an  observer 
looking  into  the  muzzle.  (Fig.  3,  Plate  65.)  Impressions  of 
the  vent  and  of  the  bottom  of  the  bore  can  be  taken  properly 
only  by  the  use  of  the  appropriate  instrument;  nevertheless, 
by  the  exercise  of  a  little  skill  and  ingenuity,  tolerably  fair 
results  may  be  obtained  with  the  improvised  instruments  just 
described.  Considerable  practice  is  required  to  get  good  smooth 
impressions,  and,  with  the  vent,  several  have  sometimes  to  be 
taken  before  one  is  obtained  which  can  be  relied  on  to  show  hair- 
lines. When  it  is  desirable  to  preserve  an  impression  for  future 
reference  or  comparison,  a  label  is  gummed  to  its  back,  giving 
the  number  of  the  gun,  date  of  taking  it,  and  the  position  of  the 
flaw. 

Should  any  defects  be  discovered  in  the  bore  (not  including  the 
immediate  vicinity  of  the  vent)  they  need  not  be  considered  seri- 
ous, unless,  in  the  case  of  smooth-bore  guns,  they  are  0.1  inch  deep 
in  rear  of  or  0.2  inch  deep  in  front  of  the  trunnions,  or  unless 
they  have  jagged  edges  likely  to  retain  pieces  of  ignited  cartridge ; 
and  in  the  ease  of  rifled  guns,  unless,  in  addition,  they  are  new 
defects  not  shown  in  the  memorandum  of  former  inspections,  or 
old  ones  which  have  materially  increased.  Generally  speaking, 
the  depth  of  a  defect  is  of  more  importance  than  its  extent. 
With  the  converted  gun,  should  a  defective  weld  run  a  consider- 
able distance  around  the  tube  of  the  bore,  it  would  be  liable  to 
part  at  that  point,  and  the  piece  should  be  considered  unservice- 
able. The  best  method  of  testing  a  gun  is  to  take  an  impression 
of  the  defect;  then  to  fire  a  few  rounds  with  service  charges  and 
take  another  impression.  If,  on  comparing  these  impressions, 
the  defect  does  not  appear  to  have  increased,  the  piece  may  be 
considered  serviceable.  As  a  precaution  against  accident,  in  case 
of  the  splitting  of  the  inner  tube  of  converted  rifle  guns,  a  gas 
escape  or  indicator  is  provided.  This  is  a  small  hole  similar  to 
the  vent  bored  through  the  cast-iron  case  on  the  side  opposite 
the  vent,  and  connecting  with  a  shallow  spiral  groove  cut  around 
the  outer  tube  near  the  seat  of  the  charge.  Should  the  tube 
split,  smoke  will  be  seen  issuing  from  the  hole,  and  firing  should 
be  discontinued. 

Examination  of  the  vent.    Especial  care  should  be  given  to 


308         MODE  OF  EXAMINING  CANNON. 

this,  for  the  reason  that  the  amount  of  firing  to  which  a  piece 
has  been  subjected  is  pretty  well  indicated  by  the  wearing  away 
of  the  vent. 

The  standard  gauge  (0.2  inch)  will  be  used  to  ascertain  the  gen- 
eral enlargement,  and  the  searcher  to  detect  defects  that  may 
have  been  developed  in  firing.  The  vent  channel  is  first  thor- 
oughly cleaned  and  then  tested  with  a  set  of  cylindrical  gauges 
differing  from  each  other  by  0.01  of  an  inch. 

The  greater  the  calibre  and  the  heavier  the  charges,  the  more 
rapidly  is  the  wear  manifested  on  the  interior  and  exterior  of 
the  vent.  The  following,  however,  is  the  average  wearing  of 
the  vent  for  the  heavier  classes  of  cast-iron  guns. 

dumber  of  rounds 100         200         300         400         500 

Diameter  of  vent 0/24        0.26        0.30        0.35        0.40 

These,  combined  with  examination  of  the  interior  orifice,  will 
enable  a  very  correct  judgment  to  be  formed  of  the  probable 
number  of  fires  sustained  and  the  duration  of  the  gun. 

The  enlargement  does  not  extend  very  far  from  the  lower 
orifice  until  the  enlargement  on  the  exterior  has  reached  a  diam- 
eter of  0.3  of  an  inch. 

So  long  as  the  wear  is  regular  and  the  fissures,  although  nu- 
merous, do  not  exceed  0.5  of  an  inch,  the  indications  are  good. 
If  the  cracks  are  few  or  diminish  in  number,  running  into  each 
other  and  extending  rapidly,  it  is  a  very  unfavorable  sign. 

Should  it  be  found  that  the  vent  has  enlarged  so  as  to  admit 
the  0.4-inch  gauge,  the  vent  is  either  bushed  or  is  filled  with  zinc 
and  a  new  one  bored,  as  the  character  of  the  gun  may  require. 
A  clean  impression  should  be  taken  of  the  bottom  of  the  vent. 
Unless  the  proper  instrument  is  provided  for  doing  this,  it  will  be 
found  to  be  a  difficult  operation,  and  should  be  repeated  several 
times.  If  the  vent  be  unbushed,  the  effect  of  service  is  seen  by 
a  gradual  increase  of  the  channel  and  by  an  irregular  wearing 
away  of  the  bottom  {Fig.  4,  Plate  55)  and  the  formation  of  fis- 
sures and  hair-lines  radiating  from  the  edges  of  the  orifice.  The 
extent  of  these  defects  is  measured  on  the  impression,  and  if. 
found  to  be  less  than  half  an  inch  in  extent  from  the  original 
centre,  the  piece  will  be  reported  for  bushing  or  to  have  a  new 
vent  bored ;  if  greater  than  this,  the  piece  should  be  reported  as 
unserviceable. 

The  defects  usually  found  around  the  vents  of  bushed  guns 
are  the  giving  way  of  the  iron  around  the  bush  from  the  gas 
getting  in  between  the  two  metals  (Fig.  5),  and  the  fissures  or 
hair-lines  which  radiate  in  the  iron  from  the  edge  of  the  bush. 
(Fig.  6.)  The  metal  around  the  bush  gives  way  almost  immedi- 
ately after  a  gun  is  bushed,  forming  a  hollow  ring  around  it 


DISABLING   CANNON.  809 

which  gradually  increases.  So  long  as  this  wear  is  uniform  and 
the  edges  are  not  jagged,  it.  is  of  little  importance,  and  guns  need 
not  be  rebushed  or  condemned  for  this  cause  until  the  ring  has 
become  0.1  of  an  inch  deep  or  0.1  of  an  inch  wide.  If,  however, 
the  edges  are  jagged,  or  if  one  side  has  given  way  much  more 
than  the  other,  so  as  to  be  likely  to  hold  pieces  of  unconsumed 
cartridge,  the  examiner  must  use  his  discretion  as  to  condemning 
the  gun,  it  being  impossible  to  lay  down  fixed  rules  suitable  for 
all  cases.  Fissures  or  hair-lines  radiating  in  the  iron  from  the 
edge  of  the  bush,  should  be  carefully  traced  on  the  gutta-percha 
impression,  and  if  they  extend  more  than  one-twentieth  of  ihe 
circumference  of  the  bore  in  any  direction,  measured  from  the 
original  centre,  the  pieces  should  be  condemned. 

564*  Disabling  cannon.  This  is  either  permanent  or  tem- 
porary. The  first  is  accomplished  by  bursting,  or  \i  the  piece  is 
rifled,  by  scoring  the  surface  of  the  bore  so  as  to  destroy  the 
efficiency  of  the  rifling. 

To  burst  a  piece,  load  it  with  a  double  charge ;  musket  or  other 
violent  powder  is  the  best;  put  in  a  projectile  and  ram  down 
around  it  iron  wedges,  the  more  tapering  the  better;  throw  sand 
in  to  make  the  wedges  take  hold,  and  tire  the  piece.  If  wedges 
are  not  at  hand,  large  spikes  or  similar  pieces  of  iron  will  answer 
the  purpose;  or  load  the  piece  as  before,  fill  it  full  with  its  own 
projectiles,  and  fire  at  a  high  elevation. 

To  fire  the  piece,  when  electrical  primers  are  not  to  be  had, 
prime  with  fine-grained  powder,  and  place  over  the  vent  a  p.'ece 
of  port-fire  long  enough  to  permit  the  man  firing  it  to  reach  a 
place  of  safety  before  the  charge  explodes.  The  port-fire  is 
held  in  position  by  being  set  in  clay  or  putty,  or  it  may  be  tied 
to  the  piece  with  twine. 

If  port-fire  is  not  at  hand,  a  slow  match  can,  in  a  few  min- 
utes, be  made  of  any  ordinary  paper  by  saturating  it  with  a 
solution  of  saltpetre  (gunpowder  dissolved  in  water  will  an- 
swer); after  drying,  cut  it  into  strips,  and  slightly  twist  them; 
place  one  end  of  a  twist  in  contact  with  the  priming  of  the  vent, 
and  apply  fire  to  the  other. 

To  disable  a  piece  by  scoring  the  bore,  load  it  with  a  charge 
of  powder  and  a  shell  filled  wiih  powder.  The  shell  is  without 
a  fuse,  and  the  fuse  hole  is  closed  sufficient  only  to  keep  the 
powder  from  spilling  out;  the  shell  is  inserted  with  the  fuse-end 
foremost  and  the  piece  fired.  The  bursting  of  the  shell  in  the 
bore  and  the  scoring  effect  of  the  fragments  will  most  likely  tear 
away  the  lands  and  render  the  piece  unserviceable. 

Cannon  are  temporarily  disabled  to  prevent  them  from  being 
immediately  used  by  the  enemy,  and  also  when  they  are  ex- 


310  PRESERVATION   OF    PROJECTILES. 

pected  to  be  retaken.    This  operation  is  accomplished  by  means 
of  a  spike. 

A  spike  is  made  of  hardened  steel,  with  a  soft  point  that  may 
be  clinched  on  the  inside  of  the  piece.  A  nail  without  a  head* 
or  the  point  of  a  file,  may  be  used  instead  of  a  regular  spike. 

To  spike  a  piece.  Drive  in  the  spike  flush  with  the  outer 
surface  of  the  vent,  and  clinch  it  on  the  inside  with  the  rammer. 
To  prevent  the  spike  from  being  blown  out,  wedge  a  shot  in  the 
bottom  of  the  bore  by  wrapping  it  with  cloth,  or  by  means  of 
wedges  driven  in  with  a  bar. 

To  unspike.  If  the  bore  is  unobstructed  and  the  spike  be  not 
screwed  or  clinched  in,  put  a  heavy  charge  of  powder  in  the 
piece  and  ram  junk- wads  tightly  over  it,  laying  on  the  bottom 
of  the  bore  a  strip  of  wood,  with  a  groove  on  the  under  side,  for 
a  strand  of  quick  match,  by  which  fire  is  communicated  to  the 
charge.  When  the  bore  is  obstructed,  endeavor  to  drive  the 
spike  into  the  bore  with  a  punch.  If  this  succeeds,  introduce 
fine-grain  powder  into  the  vent  to  blow  the  obstacle  out.  If. 
after  several  trials,  neither  of  these  methods  succeeds,  drill  out 
the  spike  or  drill  a  new  vent. 

A  gun  upon  an  iron  carriage  is  readily  dismounted  and  the 
carriage  disabled  by  removing  the  counter-hurters,  running  the 
piece  from  battery,  throwing  the  axles  in  gear,  and  then  firing 
it.  The  recoil  will  carry  the  top-carriage  oft*  the  chassis,  and 
the  fall  will  smash  it  to  pieces.  If  the  pintle  key  be  removed, 
the  chassis  will  also  be  thrown  off  and  injured.  When  it  is  not 
desirable  to  fire  the  piece,  the  top-carriage  may  be  hauled  off  by 
means  of  a  tackle. 

Preservation  of  Projectiles. 

565.  Projectiles  for  rifle  guns  should  be  neither  lacquered 
nor  painted,  for  the  reason  that  either  of  these  substances  would 
adhere  to  and  foul  the  grooves  of  the  piece.  When  practicable, 
they  should  be  kept  under  cover,  in  a  dry  place,  and  if  unboxed, 
should  be  oiled  once  a  year  with  sperm  oil.  They  are  piled,  ac- 
cording to  kind  and  calibre,  on  their  sides,  in  tiers  of  convenient 
height.  The  fuse  holes  should  be  stopped  with  tow  or  cotton- 
waste.  Great  care  should  be  taken  when  handling  them  to 
avoid  injuring  the  sabot.  No  shells  of  any  description  should 
be  kept  habitually  charged.  This  is  done,  as  occasion  requires, 
when  firing. 

Rifle  projectiles  for  all  calibres  above  4.5-inch  are  packed  sep- 
arately in  boxes.  The  boxes  have  rope  handles,  and  are  marked 
with  the  kind  of  projectile.    Projectiles  thus  packed  should  be 


PRESERVATION   OF   PROJECTILES.  311 

stored  in  a  dry  place,  and  not  removed  from  their  boxes  until 
required  for  use. 

Projectiles  for  siege  guns  are  packed  in  boxes,  painted  differ- 
ent colors  to  indicate  their  contents.  Those  for  solid  shot  are 
painted  olioe;  for  shell,  black;  for  case-shot,  red;  for  canister, 
light  drab.  The  kind  of  ammunition  is  furthermore  marked,  on 
each  end  of  the  box,  in  large  white  letters,  and  the  place  and 
date  of  fabrication  on  the  inside  of  the  cover.  Each  box  for 
siege -gun  ammunition  contains  four  projectiles  and  weighs  about 
145  pounds.  The  box  is  20  inches  long  by  11.5  inches  wide  and 
13.5  inches  deep,  outside  measurement;  it  has  two  partitions 
across  it,  the  space  between  the  partitions  holding  the  car- 
tridges; the  two  outside  spaces,  two  projectiles  each.  The 
boards  of  which  the  partitions  are  formed  are  thick  enough  to 
allow  of  a  recess  being  cut  in  each,  in  which  are  carried  the  req- 
uisite number  of  fuses  and  friction-primers.  The  boxes  have 
rope  beckets  on  their  ends  for  convenience  of  handling. 

Ammunition  for  the  3.5-inch  guns  is  put  up  in  a  similar  man- 
ner, each  box  containing  ten  rounds  and  weighing  about  135 
pounds. 

When  projectiles  of  any  kind  are  received  at  a  post,  they 
should  be  carefully  examined  and  gauged,  to  see  that  they  are 
of  the  proper  calibre  and  quality  required  for  the  particular 
piece. 

Spherical  projectiles  are  lacquered.  This  is  done  as  soon  as 
possible  after  they  are  received.  The  lacquer  used  is  coal-tar, 
applied  with  a  brush,  as  for  guns.  All  rust  should  be  carefully 
removed,  by  scraping  and  wiping,  before  the  lacquer  is  applied. 

The  projectiles  are  assorted  as  to  kind  and  calibre  and  piled 
in  a  dry  locality  where  there  is  a  free  circulation  of  air.  The 
ground  is  prepared  for  the  base  of  the  pile  by  raising  it  above 
the  surrounding  level  so  as  to  drain  oft'  the  water;  it  is  made 
level,  rammed  well,  and  covered  with  a  layer  of  sand.  The 
bottom  tier  of  the  pile  is  made  of  unserviceable  balls,  buried 
about  two-thirds  of  their  diameter  in  the  sand ;  this  base  may 
be  made  permanent.  The  pile  is  then  formed,  putting  the 
fuse  holes  of  shells  downward  in  the  intervals,  and  not  rest- 
ing on  the  shells  below.  The  bed  may  also  be  made  of  brick, 
concrete,  or  stone  pavement,  with  borders  and  braces  of  iron ; 
or  the  bed  and  border  may  be  made  of  heavy  plank  and  scant- 
ling. These,  however,  in  consequence  of  decay,  will  require 
renewing  every  six  or  seven  years.  When  for  this  or  any  other 
purpose  the  pile  is  taken  down,  the  projectiles  should  be  freshly 
lacquered.  It  is  generally  sufficient  that  the  projectiles  be  lac- 
quered, without  disturbing  the  pile,  by  applying  it  to  those  on 


312  3T0RE-H0USBS. 

the  outside.  This  is  done  once  a  year  in  warm,  dry  weather. 
When  the  lacquer  accumulates  so  that  the  projectiles  will  not 
pass  through  the  large  gauge  or  into  the  piece,  it  must  be  re- 
moved. This  is  done  by  rolling  and  scraping;  or  for  those  of 
10-inch  and  upwards  it  may  be  burned  off,  provided  the  burning 
be  quick,  so  as  not  to  heat  the  projectile  to  any  givat  extent. 

Piles  of  projectiles  should  not  exceed  eight  feet  in  width. 
Square  piles  are  to  be  preferred  where  there  in  room ;  where  this 
is  wanting,  the  piles  may  be  extended  in  length.  The  piles 
should  be  examined  every  spring  to  see  that  the  projectiles  are 
not  rusting;  this  can  be  sufficiently  done  by  removing  a  few 
from  each  pile  and  looking  through  the  crevices. 

To  find  the  number  of  balls  in  a  pile.  Multiply  the  sum  of 
the  number  of  balls  in  the  three  parallel  edges  by  one-third  of 
the  number  in  a  triangular  face.  In  a  square  pile,  one  of  the 
parallel  edges  contains  but  one  ball ;  in  a  triangular  pile,  two  of 
the  edges  have  but  one  ball  each. 

Store-houses. 

566.  Every  post  furnished  with  heavy  artillery  has  one  or 
more  store-houses  for  the  preservation  and  safe-keeping  of  equip- 
ments, implements,  and  such  machines  as  should  not  be  exposed 
to  the  weather.  They  should  be  light,  dry,  well  ventilated,  and 
furnished  with  shelves,  racks,  and  tables  for  the  accommodation 
of  the  stores  kept  therein.  The  articles  are  sorted  according  to 
their  natures  and  arranged  in  appropriate  places.  These  places 
are  distinctly  labeled,  and.  furthermore,  each  article,  as  far  as 
possible,  should  be  marked,  so  that  under  no  circumstance  there 
may  be  mistakes  or  confusion. 

Cartridge-bags  are  preserved  from  moths  by  packing  them 
with  an  hydraulic  press;  by  enveloping  them  in  paper  bags  her- 
metically sealed,  the  paper  being  similar  to  that  used  for  pre- 
serving army  clothing;  or  by  heading  them  up  in  tight  casks.  A 
mild  infusion  of  colocynth  will  preserve  them  from  moth*.  The 
bags  are  steeped  in  it,  afterwards  dried,  and  then  packed  away. 

Sponges  are  preserved  from  moths  and  packed  away  in  the 
same  manner  as  cartridge-bags.  They  should  not  be  kept  on 
the  heads  of  sponges  in  store,  as  they  are  then  always  damaged 
by  rats  and  moths.  Sponge-covers  must  never  be  put  on  the 
sponge-head  unless  both  are  clean  and  dry ;  after  use  the  sponge 
should  be  washed  clean  and  dried,  and  then  the  cover  put  on. 

Sponges,  rammers*  worms,  and  ladles  are  generally  placed  on 
racks,  with  supports,  not  over  three  feet  apart,  to  prevent  the 
staves  from  warping. 


STORE-HOUSES.  313 

Articles  composed  of  brass  are  .spread  out  on  shelves,  and  are 
kept  clean  and  free  from  verdigris.  It  is  forbidden  by  regula- 
tions to  use  oil  or  grease  upon  them ;  alcohol  or  vinegar,  with 
rotten-stone  and  afterwards  whiting,  are  the  most  suitable  pol- 
ishing materials  for  them ;  all  scouring  is  to  be  avoided.  A  good 
lacquer  for  brass  articles  is  composed  of :  Alcohol,  95  per  cent., 
2  ounces;  seed-lac,  1  ounce.  Put  the  mixture  in  a  glass  vessel 
for  five  or  six  days,  exposed  to  the  light ;  shake  well  once  each 
day ;  apply  with  a  brush  while  the  article  is  as  hot  as  it  can  be 
made  without  injury. 

Steel  or  iron  implements  should  be  painted  black  or  kept  bright, 
according  to  the  use  for  which  they  are  intended.  For  polish- 
ing, use  crocus-cloth,  oil,  and  rotten-fctone ;  after  which,  oil  with 
sperm  oil. 

For  the  preservation  of  the  bright  parts  of  machinery,  elevating 
screws,  &c,  when  not  in  use,  the  following  preparation  is  used, 
viz.  :  One  pound  white-lead  and  0.25  pound  tallow  or  lard  oil, 
heated  and  mixed  together.  This  is  applied  warm  with  a  brush 
or  cloth.  It  is  removed  by  rubbing  off  with  a  cloth,  using  a 
little  turpentine. 

Leather  equipments  are  hung  on  pegs  in  a  cool,  airy  place. 
Those  of  russet  leather  should  be  taken  down  three  or  four 
times  a  year  and  brushed  off  to  prevent  accumulation  of  mould. 
Those  of  black  leather  should,  once  or  twice  a  year,  be  washed 
with  castile  soap  and  water,  well  rubbed,  and  before  thoroughly 
dry  oiled  with  a  mixture  of  neat's-foot  oil  and  tallow ;  lamp- 
black may  be  added  to  the  oil  for  blacking. 

Fuses,  friction-primers,  and  water-caps  are  kept,  as  far  as  pos- 
sible, in  their  original  packages,  and  are  stored  in  the  driest 
and  safest  place  in  the  store-house ;  it  is  preferable  to  store  such 
articles  as  indicated  in  par.  567. 

Ropes  are  stored  and  cared  for  as  explained  in  par,  481. 

Pulley-blocks  are  hung  up  or  piled  where  they  have  free  circu- 
lation of  air ;  those  of  wood  are  occasionally  oiled  with  raw  lin- 
seed oil.  The  hooks,  cheeks,  and  partitions  of  iron  blocks  are 
painted  black.  Journals  should  be  coated  with  black-lead,  or  if 
this  is  not  available,  lubricating  oil  must  be  applied  before  using. 
The  greatest  care  must  be  observed  to  keep  them  free  from  sand 
or  other  gritty  substance. 

Rollers,  manceuverina  blocks,  shifting-planks,  chocks,  cradles, 
capstans,  and  capstan-oars  are  stored  in  dry  places.  They  should 
not  be  painted,  but  occasionally  oiled  with  raw  linseed  oil. 

Gins  are  painted  olive,  with  the  iron  parts  black.  The  wind- 
lass, however,  should  never  be  painted,  but  oiled  with  linseed 
oil. 


314  STORE-HOUSES. 

As  strict  uniformity  is  not  observed  in  the  construction  of  gins, 
each  one  should  be  numbered  and  its  parts  so  marked  that  if  parts 
of  different,  gins  become  mixed  they  may  be  readily  separated. 
Each  gin  should  be  placed  by  itself,  the  braces  fastened  to  the 
legs  by  their  bolts  and  keyed  up ;  the  clevis  and  clevis  bolt  are 
left  on  the  pry-pole. 

Trunnion  rings,  sling-chains,  &c,  are  hung  on  pegs  and  pre- 
served from  rust  by  a  thin  coat  of  black  paint. 

Hydraulic-jacks  should  be  kept  filled.  The  ram  or  piston  and 
the  journals  are  frequently  oiled  to  prevent  rusting,  but  when 
used,  the  head  of  the  ram,  to  prevent  slipping,  must  be  free 
from  oil  or  grease.     The  outside  of  the  jack  may  be  painted. 

Gatling  guns  are  kept  in  dry  store-houses,  and  require  the 
greatest  care  to  preserve  them  from  rust.  The  use  of  emery- 
cloih  or  other  scouring  material  must  be  avoided.  They  must- 
be  kept  covered,  and  well  oiled  with  a  mixture  of  about  equal 
parts  of  sperm  and  kerosene  oil.  Every  two  or  three  days  they 
should  be  wiped  off,  a  rag  passed  through  the  barrels,  and  fresh 
oil  applied.  The  journals  are  oiled  through  the  oil  holes  in  the 
breech  casing.  The  carriages,  limbers,  and  caissons  are  painted 
and  cared  for  as  other  wooden  carriages. 

Gun-lifts  are  painted  olive,  and  when  not  in  use  are  kept 
under  cover. 

Hand-carts,  sling-carts,  garrison  trucks  and  wagons  are  painted 
the  same  as  siege  carriages,  and  should  be  kept  under  sheds. 
The  small  sling-cart,  being  entirely  of  iron,  excepting  the  pole, 
is  painted  the  same  as  iron  carriage's. 

Paints,  turpentine,  oils,  lacquers,  &c,  are  kept  in  a  room  sepa- 
rate from  other  stores ;  a  cellar  or  casemate  is  preferable.  The 
floor  should  be  covered  with  two  or  three  inches  of  fine  sand, 
which  should  be  renewed  occasionally.  Sawdust  should  never 
be  used  for  the  floor. 

Volatile  oils,  such  as  kerosene  or  benzine,  must  not  be  kept 
stored  in  the  paint  and  oil  room,  but  in  such  place  that  the  least 
possible  damage  will  arise  from  it  should  it  take  tire. 

Paint  brushes,  when  new,  and  before  using,  should  be  wrapped, 
or,  as  painters  terra  it,  bridled  with  strong  twine,  and  soaked  in 
water  to  swell  them.  After  using,  they  should  be  cleaned  with 
spirits  of  turpentine  and  put  away  in  a  vessel  containing  water 
to  keep  them  from  drying  and  becoming  unpliable. 

567.  The  following  table  gives  the  quantity  of  material  re- 
quired for  the  preservation  of  the  armament  of  a  fort.  It  is  made 
upon  the  basis  of  what  is  required  annually  for  ten  pieces,  car- 
riages, &c,  of  each  kind : 


STORE-HOUSES. 


■titvM  'uelori     £25' 


1 


'tub  'tpop-jCimiis 


■jo  ajsdml  'nodpj.    \—-—  ! 


70  om  ^apq-qiEa 


ills 


4 ft  II 


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£    5  =  « 


If 

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li   if  Sits 


Ijifsl!! 


■  f§faf 


316  PRESERVATION   OF   POWDER. 

Armament  of  Works. 

568.  The  kind,  calibre,  and  number  of  cannon  constituting 
the  armament  of  a  permanent  work,  as  likewise  the  emplace- 
ment of  the  piece,  is  determined  by  the  Engineer  Bureau.  The 
•different  parts  of  a  work  receive  their  specific  designation  from 
the  same  source%  which  likewise  numbers,  in  regular  series,  the 
position  of  the  pieces  occupying  each  part.  These  numbers,  run- 
ning from  right  to  left  as  you  look  outwards,  are  placed  on  the 
parapet  opposite  the  platform. 

It  is  the  duty  of  the  Engineer  Bureau  to  furnish  each  work 
with  a  chart  showing  the  water  channels,  with  their  soundings, 
.and  other  approaches  to  the  work.  From  this  it  is  the  duty  of 
«^ach  artillery  officer  in  charge  of  pieces  to  study  and  familiarize 
himself  with  the  method  of  using  them  so  as  to  make  them  most 
effective  in  carrying  out  the  object  for  which  they  were  placed 
in  the  work. 

Supply  of  ammunition. 

The  amount  of  ammunition  which  should  constitute  a  supply 
for  artillery  in  a  permanent  work,  depends  so  much  upon  cir- 
•cumstances  that  no  fixed  rule  can  be  laid  down  for  it.  A  place 
liable  to  close  siege  should  be  more  amply  supplied  than  one 
which  can  be  replenished,  and  less  would  be  required  to  repel 
attacks  from  vessels  than  from  a  besieging  force  on  land.  Two 
hundred  rounds  per  piece  may  be  taken  ordinarily  as  a  good 
supply  for  15-inch  guns  and  the  heavier  calibres  of  rifles ;  greater 
amounts  are  required  for  smaller  calibres. 

For  all  guns,  the  projectiles  should  be  about  equally  divided 
between  shell  and  solid  shot. 

The  amount  of  ammunition  for  siege  guns,  when  used  in  cam- 
paign as  heavy  field-pieces,  is  200  rounds  per  piece,  together 
with  a  small  reserve. 

Preservation  of  Powder. 

569.  Powder  is  kept  in  magazines  constructed  with  the  works. 
"The  number  of  these  magazines  depends  on  the  number  and 
-calibre  of  pieces  in  the  work  and  the  probable  amount  of  ammu- 
nition required  for  each. 

Magazines  are  of  two  kinds,  viz.:  storage  and  service.  The 
former  are  for  the  accommodation  of  powder  in  bulk  ;  the  laUer 
a.re  smaller  than  the  former,  and  are  placed  as  convenient  as 
practicable  to  the  pieces  to  be  served,  and  contain  only  sufficient 
powder  for  immediate  use.  Adjoining  or  convenient  to  each 
service  magazine  is  a  filling-room,  in  which  cartridges  are  made 


PRESERVATION   OF   POWDBR.  317 

up  and  shells  filled.  Powder  is  brought  from  the  magazine  for 
this  purpose,  but  only  in  such  quantities,  at  a  time,  as  may  bo 
necessary.  In  the  filling-room  are  kept  the  filling  implements 
and  such  small  articles  of  equipment  as  are  required  to  be  near 
the  pieces. 

Tiie  storage  magazines  of  a  post  are  conspicuously  marked 
A,  8,  C,  &c;  the  service  magazines  are  numbered  1,  2,  3,  &c, 
and,  in  addition,  are  marked  for  the  particular  pieces  they  are 
to  serve. 

A  magazine  of  sufficient  size,  and  fitted  up  with  shelves, 
tables,  and  racks,  is  set  aside  for  the  storage  of  rockets,  port- 
fires, fuses,  primers,  slow  and  quick  match,  and  other  similar 
articles.  No  such  stores  will  be  permitted  in  a  magazine  with 
powder. 

The  keys  of  the  storage  magazines  are  kept  by  the  command- 
ing officer  of  the  post.  Those  of  the  service  magazines,  unless 
otherwise  ordered,  are  in  possession  of  the  officers  having  charge 
of  the  particular  pieces  to  be  served  from  them,  a  competent  non- 
commissioned officer  being  assigned  to  the  immediate  care  of 
each.  The  ord nance-sergeant  of  the  post  will  have  charge  of 
the  storage  magazines  and  of  the  one  containing  fuses,  port-fires, 
&e. 

Powder  is  stored  in  barrels  containing  100  pounds  each ;  the 
heads  of  the  barrels  are  painted  black,  so  as  to  show  more  plainly 
the  marks,  which  are  stenciled  in  white.  Each  barrel  is  marked 
on  both  heads  with  the  number  of  the  barrel,  the  name  of  the 
manufacturer,  year  of  fabrication,  and  the  kind  of  powder — can- 
non* mortar,  musket,  mammoth,  or  hexagonal ;  the  mean  initial 
velocity,  and  the  pressure  per  square  inch  on  the  pressure  piston. 
Each  time  the  powder  is  proved  the  initial  velocity  is  marked 
below  the  former  proof-marks,  and  the  date  of  trial  opposite  it. 
Each  manufacturer  has,  in  addition,  certain  private  marks — 
initial  letters — denoting  the  particular  grade  to  which  the  powder 
belong!».  A  book  is  kept,  by  the  ordnance-sergeant,  which  shows, 
besides  all  these  marks,  when  the  powder  was  received,  where 
stored,  and  how  much  on  hand. 

Barrels  of  different  kinds  of  powder  are  piled  separately,  and, 
besides  being  recorded  in  the  magazine  -  book,  each  parcel  is 
marked  with  a  card,  showing  the  kind  and  the  entries  and  issues. 

In  the  magazine,  the  barrels  are  placed  on  their  sides,  gener- 
ally three  tiers  high,  or  four  tiers  if  absolutely  necessary.  Small 
skids  are  placed  on  the  floor  and  between  The  several  tiers,  and 
the  barrels  chocked  at  intervals  to  prevent  rolling.  The  tiers 
must  be  so  arranged  that  the  marks  can  readily  be  seen  and  any 
particular  kind  reached.    There  should  be  an  unobstructed  space 


~318  PRESERVATION   OF  POWDER. 

of  several  square  yards  at  the  door,  and  this  space,  as  likewise 
the  alleys,  should  be  covered  with  carpet  or  matting.  The  mag- 
azine is  provided  with  a  well  near  the  door;  into  this  the  sweep- 
ing? are  put ;  they  should  never  be  swept  out  at  the  door.  For 
the  preservation  of  the  magazine,  it  is  of  the  greatest  importance 
to  keep  unobstructed  the  circulation  of  air,  under  as  well  as 
above  the  flooring.  The  magazine  should  be  opened  and  aired 
011I3*  in  clear,  dry  weather,  when  the  temperature  of  the  air  out- 
si"  le  is  lower  than  that  inside  of  the  magazine.  It  should  not  be 
opened  in  damp  weather  if  it  can  be  avoided.  The  ventilators 
must  be  kept  free  and  no  shrubbeiy  or  trees  allowed  to  grow  so 
near  as  to  screen  the  building  from  the  sun.  The  magazine 
yard  should  be  of  sand  or  clay  and  well  drained.  The  moisture 
of  a  magazine  may  be  absorbed  by  chloride  of  lime  kept  in  an 
open  vessel  and  renewed  from  time  to  time.  Quick-lime  is  dan- 
gerous, and  should  not  be  used. 

Candles,  in  lanterns,  are  used  for  lighting  the  magazine.  No 
one  should  enter  without  first  removing  nis  shoes  or  putting1 
india-rubbers  over  them.  No  cane,  sword,  or  anything  which 
might  occasion  sparks,  must  be  carried  in. 

Barrels  of  powder  must  not  be  rolled  in  transportation;  they 
should  be  carried  in  hand-barrows,  or  in  slings  made  of  rope, 
•canvas,  or  leather.  All  implements  used  in  the  magazine  or  on 
the  barrels  should  be  of  copper  or  wood.  The  barrels  must  never 
be  repaired  in  the  magazine.  When  it  is  necessary  to  roll  them 
for  the  better  preservation  of  the  powder  and  to  prevent  its  cak- 
ing, this  is  done,  with  a  small  number  at  a  time,  on  boards  in 
the  yard. 

Occasionally,  especially  in  the  spring,  the  barrels  should  be 
inspected,  and,  as  far  as  possible,  brushed  off,  to  prevent  insects 
from  destroying  the  hoops.  A  light  brushing  over  with  carbolic 
.acid  will  be  good  for  this. 

When  practicable,  a  sentinel  should  be  posted  over  the  maga- 
zine, to  keep  unauthorized  persons  away  and  to  prevent  smoking 
or  the  within  dangerous  proximity.  The  lightning-rods  must 
never  he  out  of  repair. 

Should  a  fire  occur  near  the  magazine,  the  ventilators  and 
windows  must  be  immediately  closed,  and  the  building  covered, 
if  possible,  with  paulius.  blankets,  or  carpets  saturated  with 
water.  It  is  extremely  hazardous  to  attempt  to  remove  the  con- 
tents at  such  a  time. 

Neither  loaded  shells,  fire-works,  nor  composition  for  fire- 
works will  he  stored  in  a  magazine  with  powder.  Shells  should 
oe  filled  in  the  filling-room  of  the  service  magazine. 

Transportation.    In  wagous,  the  barrels  of  powder  must  be 


FILLING   CARTRIDGE-BAGS.  319 

packed  in  straw,  secured  in  such  a  manner  as  not  to  rub  against 
each  other,  and  the  load  closely  covered  with  canvas.  Sufficient 
guard  should  accompany  the  train  to  prevent  all  smoking  or  Arc 
near  the  wagons.  Nq  camp-fires  should  be  allowed  near  the 
park.  On  railroads,  each  barrel  should  be  tightly  boxed  and 
packed  so  as  to  avoid  friction ;  the  cars,  if  practicable,  should 
have  springs  similar  to  those  for  passenger  cars. 

5  TO.  Filling  cartridges-bags.  Cartridges  for  all  pieces  larger 
than  the  siego  gun  should  be  made  up  only  as  required  for  use, 
and  when  any  are  left  over  after  firing,  they  are  stored  away  in 
the  service  magazine  on  shelves.  The  cartridges  are  filled  in  the 
JUUng-room  of  the  service  magazine.  Under  no  circumstances 
will  filling  be  done  in  a  powder  magazine.  The  powder,  in  bar- 
rels, is  carried  from  the  storage  magazine  to  the  service  maga- 
zine in  powder-carts  or  hand-barrows. 

To  fill  the  cartridges,  the  implements  required  are  :  One  cop- 
per hammer,  one  wooden  drift,  one  counter  brush,  one  scoop,  one 
counter  scales  and  weights  (brass  or  copper),  one  fitting  Junnel, 
one  set  powder  measures \  cartridge-bag^,  and  twine. 

The  barrels  are  opened  by  first  loosening  the  upper  hoops, 
when  the  heads  can  be  taken  out  easily.  Care  should  be  taken 
not  to  handle  the  barrels  or  powder  roughly. 

Should  the  powder  be  caked  or  lumpy,  caution  should  be  ex- 
ercised in  breaking  the  lumps.  When  the  lumps  are  small  and 
not  very  hard,  they  may  be  broken  by  pressing  them  with  the 
hands;  but  when  large  and  hard,  requiring  more  force  to  break, 
the  powder  is  taken  to  some  safe  place  away  from  the  magazine, 
spread  upon  a  paulin,  and  broken  with  a  mallet.  The  grains 
must  be  separated,  but  not  crushed. 

When  cartridges  are  to  be  used  with  projectiles,  the  powder  is 
carefully  weighed;  for  blank  cartridges,  it  is  measured.  When 
the  piece  for  which  the  cartridges  are  to  be  prepared  has  a  cali- 
bre of  less  than  7  inches,  the  filling  funnel  is  used,  one  man  hold- 
ing open  the  mouth  of  the  bag  while  another  pours  the  powder 
into  it  through  the  funnel.  The  bag  is  then  tied  with  twine 
close  to  the  powder.  For  cartridges  of  more  than  7  inches  diam- 
eter, the  powder  is  poured  into  the  bag  by  means  of  the  scoop; 
the  nag  is  tied  as  before.  When  cartridges  are  filled,  each  one 
should  be  marked  with  a  pencil  or  by  stenciling,  showing  the 
kind  and  weight  of  powder  and  for  what  kind  of  piece  it  is  to 
be  used. 


lart  Jiftfc 


TRANSPORTATION  OF  ARTILLERY. 


To  Embark  and  Disembark  Artillery  and  Artillery  Stores. 

Oeneral  Rules, 

571.  When  artillery  and  its  stores  are  to  be  shipped  for  an 
expedition,  prepare  first  a  list  of  all  the  articles,  stating  their 
number,  individual  weight,  and  the  total  weight  of  each  kind. 

In  estimating  the  weights,  allow  double  for  that  of  bulky 
articles  which  occupy  much  space  without  weighing  much. 

Divide  the  total  quantity  to  be  transported  among  the  vessels, 
and  make  statements  in  duplicate  of  the  articles  on  board  each 
vessel,  one  of  which  lists  should  go  with  the  vessel  and  the  other 
remain  with  the  officer  shipping  the  stores. 

The  articles  must  be  divided  among  the  vessels  according  to 
the  circumstances  of  the  case ;  but,  as  a  general  rule,  place  in 
each  vessel  everything  necessary  for  the  service  required  at  the 
moment  of  disembarkation,  so  that  there  will  be  no  inconven- 
ience should  other  vessels  be  delayed. 

If  a  siege  is  to  be  undertaken,  place  in  each  vessel  with  each 
piece  of  artillery  its  implements,  ammunition,  and  the  carriages 
necessary  to  transport  the  whole  or  a  part ;  the  platforms,  tools, 
instruments,  and  materials  for  constructing  batteries;  skids, 
rollers,  scantling,  and  plank. 

If  a  particular  calibre  of  gun  is  necessary  for  any  operation, 
do  not  place  all  of  one  kind  in  one  vessel,  to  avoid  being  entirely 
deprived  of  them  by  an  accident  to  it. 

Dismount  the  carriages,  wagons,  and  limbers  by  taking  off 
the  wheels  and  boxes  and,  if  absolutely  necessary,  the  axle- 
trees.  Place  in  the  boxes  the  linch-pins,  washers,  <fec,  with  the 
tools  required  for  putting  the  carriage  together  again.  Number 
each  carriage,  and  mark  each  detached  article  with  the  number 
of  the  carriage  to  which  it  belongs. 

The  tixed  ammunition  must  be  carefully  packed  in  its  pre- 
scribed boxes ;  the  cartridge-bags,  fuses  for  shells,  and  their 
ammunition,  either  in  substantial  boxes  with  rope  handles  or  in 

21  ( 321 ) 


322  TRANSPORTATION  OF  ARTILLERY. 

barrels;  powder  in  barrels,  in  a  magazine  constructed  in  * 
vessel  to  hold  it. 

Sponges,  rammers,  worms,  and  ladles  should  be  united  in 
bundles ;  other  implements,  intrenching  tools,  levels,  rules,  &c, 
in  bundles  or  boxes;  implements,  in  bundles  and  boxes  of  com- 
plete sets,  as  far  as  practicable. 

Small-arms  should  be  in  their  prescribed  boxes. 

The  contents  of  each  box,  barrel,  or  bundle  should  be  marked 
distinctly  upon  it.  The  boxes  should  be  made  small  for  the 
convenience  of  handling,  and  have  rope  handles  to  lift,  them  by. 

The  position  of  the  different  articles  in  each  vessel  should  be 
noted  in  a  column  in  the  list  on  board. 

Place  the  heaviest  articles  below,  beginning  with  the  shot  and 
shells,  (empty,)  then  the  guns,  platforms,  carriages,  wagons, 
limbers,  ammunition -boxes,  &c.  Boxes  of  small-arms  and  am- 
munition in  the  driest  and  least  exposed  part  of  the  vessel. 
The  skids,  scantling,  and  boards  may  be  in  the  more  exposed 
parts,  or  in  the  run. 

Articles  required  to  be  disembarked  first  should  be  put  in  last, 
or  so  placed  that  they  can  be  readily  got  at. 

If  the  disembarkation  is  to  be  performed  in  front  of  the  enemy, 
gome  of  the  field-pieces  should  be  so  placed  that  they  can  be  dis- 
embarked immediately  with  their  carriages,  implements,  arid 
ammunition  ;  also  the  tools  and  materials  for  throwing  up  tem- 
porary intrenchments  on  landing. 

When  there  are  several  vessels  laden  with  artillery  and  stores 
for  the  expedition,  each  vessel  should  have  on  each  quarter  and 
on  a  signal  at  mast-head  a  number  that  can  be  easily  distin- 
guished at  a  distance.  The  same  number  should  be  entered  on 
a  list  of  supplies  shipped  in  each  vessel.  The  commander  can 
then  know  exactly  what  resources  he  has  with  him.  Some 
vessels,  distinguished  by  particular  signal,  should  be  laden  solely 
with  such  powder  and  ammunition  as  may  not  be  required  for 
the  immediate  service  of  the  pieces. 

If  it  is  necessary  to  reship  or  leave  any  articles  on  board  the 
vessels,  care  should  be  taken  to  note  them  on  the  list. 

Boats  of  proper  capacity  must  be  provided  for  the  disembarka- 
tion, according  to  the  circumstances  in  each  cast1. 

It  ma}'  be  necessary  to  establish  temporary  wharves  on  tres- 
tles, and  to  erect  shears,  cranes,  or  derricks. 

On  a  smooth  sandy  beach,  heavy  pieces,  &c,  may  be  landed 
by  rolling  them  overboard  as  soon  as  the  boats  ground,  and 
hauling  them  up  with  sling-carts. 

572.  Railroad  transportation.  The  most  suitable  car  for 
carrying  horses,  especially  in  warm  weather,  is  the  "slat  stock- 


TRANSPORTATION   OF   ARTILLERY.  323 

car,"  bnilt  of  slats  and  open  all  around,  but  tight  In  roof. 
Another  kind,  known  as  the  "combination  car,9'  is  made  with 
five  doors  on  each  side  and  one  at  each  end,  which  may  be 
closed  tight  for  stores,  or  with  iron  grates  when  carrying  horses. 
These  are  suitable  for  either  warm  or  cold  weather. 

Both  kinds  are  usually  27  feet  4  inches  long,  7  feet  0  Inches 
wide,  and  6  feet  8  inches  high,  inside  measurement.  Each  car 
will  carry  fourteen  artillery  or  sixteen  common  horses  or  mules. 

The  horses  all  face  towards  the  same  side  of  the  car,  and  are 
hitched  by  their  halters  to  the  frame-work.  If  the  Journey  is 
to  be  continued  beyond  eighteen  or  twenty  hours,  the  horses 
will  require  to  be  watered  and  fed.  Nose-bags  are  generally 
used  for  the  grain.  If  the  drivers  are  attentive,  they,  by  taking 
advantage  of  the  short  halts  made  by  the  train,  can  feed  grain 
4nd  hay  quite  easily  by  hand.  Half  rations  will  be  sufficient 
under  any  circumstances.  Before  placing  the  horses  on  the  cars, 
they  should  be  thoroughly  groomed  and  cooled;  they  should 
have  nothing  more  on  them  than  their  halters. 

If  the  journey  is  to  continue  for  several  days,  (but  never  be- 
yond four  without  unloading,)  the  horses  should  stand  length- 
wise of  the  car,  facing  each  other,  and  hitched  to  two  bars 
placed  for  the  purpose  across  the  car.  The  bars  have  space 
between  them  sufficient  for  feeding  purposes  and  for  a  man  to 
remain  in  charge.  When  thus  arranged  only  about  one-half  as 
many  can  be  carried  in  each  car  as  in  the  other  case.  By  load- 
ing in  this  way,  close  "box  "-cars  may,  even  in  hot  weather,  be 
used,  the  doors  being  left  open  for  ventilation. 

Horses  are  best  loaded  and  unloaded  from  a  "stock  shute," 
but  where  this  convenience  is  not  available,  and  there  is  no  plat- 
form, a  ramp  or  shute  may  be  improvised,  using  for  it  planks 
about  12  feet  long  and  from  2  to  3  inches  thick,  depending  on 
the  strength  of  the  wood. 

The  ramp  should  be  about  four  feet  wide,  with  the  planks 
firmly  fastened  together  with  transverse  battens.  These  battens, 
furthermore,  prevent  the  horses  from  slipping.  A  strong  trestle 
or  crib  of  logs  supports  the  end  of  the  ramp  next  the  car,  while 
the  other  rests  on  the  ground  and  is  secured  from  slipping  by 
strong  stakes.  An  intermediate  trestle  or  a  support  of  logs 
should  be  placed  to  prevent  the  planks  from  springing  with  the 
weight  of  the  horses.  Three  or  four  posts  of  suitable  height  are 
set  in  the  ground  on  each  side,  to  which  side  rails  are  lashed  or 
spiked  for  the  purpose  of  keeping  the  horses  from  stepping  off. 
A  board  should  be  placed  on  each  side  to  prevent  the  horses* 
feet  from  slipping  over  the  edges  of  the  planks.    When  planks 


324  TRANSPORTATION   OF   ARTILLERY. 

are  not  procurable,  a  ramp  of  earth,  supported  by  means  of  logs 
or  stone  on  the  end  next  the  track,  may  be  constructed. 

The  cars  are  brought  up  in  succession  to  the  ramp  to  be 
loaded  or  unloaded.  Mules  and  ordinary  horses  are  usually 
driven  in  loose  and  stand  unhitched. 

In  the  field,  where  no  shute  or  ramp  is  to  be  found  at  the 
place  of  unloading,  material  ready  prepared  for  constructing  one 
should  be  carried  with  the  train. 

Artillery  carriages  and  transportation-wagons  are  carried  on 
platform  or  "flat"  cars. 

These  cars  are  generally  28  feet  long  by  8  feet  wide.     When 
properly  loaded  eacli  will  carry  two  field  guns  and  two  caissons 
complete.    To  load  them  the  carriages  are  unlimbered  and  the 
spare  wheels  removed  from  the  caissons;  the  rear  train  of  a 
caisson,  its  stock  to  the  rear,  is  run  to  the  front  end  of  the  car 
and  its  stock  rested  on  the  floor;  another  rear  train  is  run 
forward  in  like  manner  until  its  wheels  strike  or  overlap  those 
of  the  first,  when  its  stock  is  rested  on  the  floor.     A  limber 
is  then  placed  on  the  car  with  its  pole  to  the  front,  resting 
on  the  rear  train ;  the  second  limber  is  backed  on  and  its  pole 
held  up  until  a  gun,  trail  foremost,  is  run  under  it;  the  trail  of 
the  gun  is  rested  on  the  floor  and  the  pole  of  the  limber  on  the 
gun  carriage.    The  other  gun  is  run  on  in  the  same  manner,  and 
its  trail  rested  on  the  floor  under  the  first  gun  ;  a  limber  is  next 
run  on  and  its  pole  rested  on  the  last  gun ;  the  remaining  limber 
is  run  on  with  its  pole  under  the  preceding  limber.     All  of  the 
carriages  are  pushed  together  as  closely  as  possible  and  firmly 
lashed.    Where  the  carriages  are  liable  to  chafe  each  other,  they 
are  bound  with  gunny-sacking  or  other  stuff. 

A  side  platform,  such  as  are  found  in  depots,  is  the  best  for 
loading.  The  carriages  are  first  run  onto  a  spare  car;  from  this 
they  are  crossed  over  on  planks  to  the  one  upon  which  they  are 
to  be  carried,  and  arranged  on  it  as  ahead}'  described.  When 
there  is  no  side  platform,  the  carriages  are  run  up  at  the  eud  of 
the  car  by  means  of  way-planks. 

Siege  guns  can  be  loaded  and  carried  in  a  similar  manner,  but 
when  there  is  no  side  platform,  blocks  and  tackle  will  be  required 
for  hauling  them  up  the  way-planks.  Two  siege  guns  with  their 
carriages  and  limbers  complete  can  be  carried  on  one  car,  and, 
in  addition,  boxes  of  ammunition  or  stores  may  be  piled  between 
and  underneath  the  carriages.  One  "flat"  car  will  carry  two- 
army  transportation-wagons  standing,  besides  a  large  quantity 
of  other  material.  If  the  wagons  are  u knocked  dovmf  the  same 
car  will  carry  four. 

Twenty-four  thousand  pounds  is  considered  a  safe  load  for  one 


TRANSPORTATION    OF    ARTILLERY   BY   SBA.  325 

<sar  on  a  good  track.  Baggage,  harness,  forage,  (fee,  arc  usually 
-carried  in  box-cars.  These  cars  have  the  same  dimensions  as 
heretofore  given  for  those  carrying  horses. 

The  average  size  passenger  car  will  »eat  sixty  men,  but  a  small 
car  will  seat  only  fifty.  The  men  must  be  provided  with  cooked 
rations  for  the  whole  trip.  Each  car  must  be  liberally  supplied 
with  drinking  water,  lights  at  night,  and  all  other  conveniences, 
to  make  it  unnecessary  for  the  men  to  leave  them  during  stop- 
pages of  the  train. 

The  officer  in  command  of  troops  on  a  train  will  act  in  har- 
mony with  the  railroad  officials,  and  must  not  interfere  in  any 
manner  whatever  with  the  running  of  the  train. 

Ten  to  fifteen  passenger  or  sixteen  to  twent}T-two  freight  cars 
go  to  make  up  a  train  drawn  by  one  locomotive ;  but  when  the 
grades  are  light  and  but  little  curvature  in  the  road,  the  maximum 
weight  of  trains  may  reach  double  these  figures. 

Passenger  trains  generally  travel  at  the  rate  of  about  twenty- 
two  miles  per  hour,  and  freight  trains  about  fifteen,  including 
customary  stoppages.  Troop  trains  should  not  be  dispatched 
from  a  station  with  less  intervals  than  ten  minutes  between 
them. 

The  experience  gained  during  the  war  of  the  rebellion  shows 
that  to  supply  an  army  of  100,000  men  in  the  field  by  means  of 
a  single  line  of  rails,  the  proportion  of  rolling  stock  should  be— 
engines  0.25  and  freight  cars  6.0  to  every  mile  of  road.  This  does 
not  provide  for  the  conveyance  of  troops.  In  calculating  the 
amount  of  rolling  stock  available  for  use,  a  deduction  of  50  per 
cent,  for  locomotives  and  30  per  cent,  for  all  other  carriages 
must  be  made  for  those  usually  undergoing  repairs. 

From  the  foregoing  data,  a  small  calculation  will  give  the 
amount  of  railroad  transportation  required  for  any  given  num- 
ber of  troops,  artillery,  or  material,  and  the  capacity  of  a  road 
for  performing  the  work. 

573.  Transportation  of  artillery  by  sea.  In  the  United  States 
service  there  are  no  vessels  fitted  up  especially  for  transportation 
of  troops,  horses,  or  artillery  material.  Even  during  the  four 
years  of  the  war  of  the  rebellion  no  attempt  was  made  towards 
it  further  than  temporary  arrangements  for  some  particular  voy- 
age. The  voyages  were  short,  lasting  generally  only  two  or 
three  days,  never  exceeding  eight.  Embarking  and  disembark- 
ing were  usually  accomplished  with  wharf  facilities.  In  only 
three  or  four  instances  were  the  movements  of  an  expeditionary 
character,  requiring  these  operations  to  be  performed  on  an  open 
beach  or  in  front  of  the  enemy.  As  desirable  and  advantageous 
as  it  would  have  been  to  have  had  suitable  transports  properly 


826  TRANSPORTATION   OF   ARTILLERY   BY   SEA. 

fitted  up,  the  absolute  necessity  for  it  was  never  felt,  and  conse- 
quently they  were  never  adopted.  It  may  not  always  occur 
that  the  same  conditions  will  exist,  and  it  is  therefore  well  to 
collect  such  information  on  the  subject  as  may  be  needed. 

The  horses  and  material  belonging  to  artillery  require  so- 
great  an  amount  of  space  in  proportion  to  that  required  for  the 
men,  the  latter  need  scarcely  be  taken  into  account  when  esti- 
mating for  ship  room.  Any  vessel  capable  of  carrying  horses 
and  guns  will  accommodate  the  men  belonging  to  tliem  in  those 
parts  where  neither  horses  nor  guns  can  be  stowed. 

Guns,  caissons,  ammunition,  and  other  material  of  this  char- 
acter are  carried  in  the  same  manner  as  ordinary  merchandise. 
When  once  within  reach  of  the  ship's  tackle,  the  officers  and  crew 
of  the  vessel  will  know  how  to  stow  and  take  care  of  them  to  the 
best  advantage.  When  practicable,  it  is  not  only  the  most  expedi- 
tious, but  altogether  the  best  way  to  leave  the  carriages  mounted. 
The  length  of  the  voyage  and  the  character  and  capacity  of  the 
vessel  will  determine  whether  or  not  this  should  be  done,  and 
in  what  part  of  the  ship  stored.  Other  considerations,  such  as 
facilities  for  embarking  and  disembarking,  will  likewise  go  to 
determine  these  questions. 

The  horses  are  more  difficult  to  provide  for,  and  it  is  with  ref- 
erence to  their  accommodation  and  safety  that  vessels  for  the 
transportation  of  artillery  should  be  selected. 

During  the  rebellion  a  species  of  transportation  was  employed 
upon  the  Chesapeake  Bay,  and  even  for  short  voyages  at  sea, 
which  proved  very  successful,  and  which  might  again  find  useful 
application. 

This  consisted  in  embarking  the  horses  on  large  schooners  and 
the  batteries  on  steamers,  (frequently  ferry-boats.)  which,  tak- 
ing the  schooners  in  tow,  conducted  them  to  their  destination. 
Each  schooner  carried  upon  an  average  fifty  horses;  three  were 
therefore  required  for  one  battery.  The.  ferry-boat  carried  easily 
the  material  of  two  batteries.  The  advantage  of  this  kind  of 
transportation  consisted  chiefly  in  the  ease  of  loading  and  un- 
loading the  vessels.  Their  light  draught  enabled  them  to  lie  up 
to  almost  any  kind  of  wharf.  Strong  gang-planks  were  pro- 
vided, over  which  the.  horses  were  led  to  the  decks  of  the 
schooners,  upon  which  they  stood,  facing  outwards.  To  prevent 
them  from  gnawing  and  injuring  the  gunwales,  stout  boards 
were  temporarily  nailed  thereon.  The  batteries  were  run  by 
hand  onto  the  ferry-boats,  the  carriages  unlimbered  and  stowed, 
the  whole  occupying  but  a  few  minutes  of  time.  Disembarking 
was  accomplished  with  equal  facility. 


TRANSPORTATION   OF   ARTILLERY   BY   8BA.  327 

Each  schooner  carried  its  due  proportion  of  the  men  of  the 
battery,  who  looked  after  the  horses. 

When  the  voyage  is  to  extend  beyond  six  or  seven  days  at  sea, 
the  vessel  should  have  room  between  decks  where  stalls  can  be 
fitted  up  in  the  manner  hereinafter  described.  But  if  the  voyage 
is  of  shorter  duration,  stalls  are  not  absolutely  necessary.  In 
this  case  the  vessel  best  adapted  is  a  long  low  steamer,  with  a 
clear  upper  deck  for  the  accommodation  of  the  horses.  The 
guns,  carriages,  harness,  and  baggage  are  stowed  between  docks, 
where  likewise  the  men  find  ample  room.  In  many  steamers  a 
large  gangway  on  each  side  leads  to  the  main  deck,  through  which 
the  carriages  can  be  run  by  hand.  In  vessels  not  so  provided 
they  have  to  be  lowered  by  means  of  tackle  down  the  main 
hatch, — a  slow  and  laborious  process. 

Horses,  in  all  cases,  should  stand  ath wart-ship ;  in  this  posi- 
tion they  better  accommodate  themselves  to  the  rolling  motion 
of  the  vessel.  When  on  the  upper  deck  they  should  face  in- 
wards; this,  for  the  reason  that  the  spray  will  not  then  strike 
them  in  their  faces,  and,  besides,  when  facing  each  other  in  this 
manner  they  will  suffer  less  from  fright  and  nervous  excitement. 
A  vessel  of  not  less  than  25  feet  beam  will  accommodate  two 
rows  of  horses,  leaving  a  space  between  the  rows,  and  between 
the  croups  of  the  animals  and  the  sides  of  the  ship,  ample  for 
the  proper  care  of  the  horses.  These  spaces  are,  furthermore, 
necessary  as  gangways  for  working  the  vessel.  The  average 
artillery  horse  occupies  a  deck  space  of  8  feet  by  2  feet  4  inches. 
It  results,  therefore,  that  the  whole  length  of  the  deck  in  feet 
divided  by  the  last  dimension  will  give  the  number  that  majr  be 
accommodated  in  each  row.  As  they  stand  better  when  close 
together,  side  by  side,  no  allowance  need  be  made  for  vacant 
space  between  them. 

The  horees  are  secured  by  their  halters  to  hitching-bars  (B  B, 
Fig.  1,  Plate  56),  of  strong  scantling,  running  longitudinally 
in  two  lines  along  the  deck.  A  space  of  about  five  feet  is  left 
between  the  lines  for  the  gangway  before  mentioned.  These 
bars  should  be  about  four  feet  from  the  deck,  and  supported  by 
stanchions  (A  A)  secured  to  the  deck  by  strong  angle-irons  fast- 
ened with  screws.  The  bars  are  braced  from  the  sides  of  the 
vessel  with  stout  scantling  (C  C).  These  braces  are  arranged  so 
that  the  spaces  between  them  will  include  five  horses,  (more  or 
less,  depending  upon  the  strength  required  t>  give  entire  secu- 
rity to  the  structure,)  and  are  fastened  with  bolts  and  nuts,  so 
that  in  loading  they  maj'  be  removed  and  replaced  successively 
as  the  horses  are  put  in  their  places.  The)r  must  be  smoothed 
off,  or  wrapped  with  gunny  or  other  material,  to  prevent  their 


328  TRANSPORTATION   OF    ARTILLERY   BY   SEA. 

chafing  the  horses.  Holes  are  bored  or  rings  attached  to  the 
hirching-bars  for  the  halter-straps  The  horses  should  be  hitched 
short,  and  when  putting  them  on  board  care  should  be  observed 
to  have  those  accustomed  to  each  other  placed  together.  Kick- 
ing and  vicious  animals  are  placed,  as  far  as  practicable,  where 
they  can  do  least  mischief. 

All  stalls,  hitch ing-bars,  or  whatever  other  arrangement  for 
securing  horses,  must  be  strong  beyond  any  possibility  of  giving 
way.  The  living  force  exerted  by  a  row  of  hoi"ses  as  thejr  swing 
with  the  motion  of  a  ship  in  a  heavy  sea-way,  is  very  great,  and 
it  is  better  to  have  no  securing  arrangements  whatever  than  to 
have  those  that,  by  giving  way,  will  wound  and  injure  the  ani- 
mals in  the  wreck. 

If  the  transport  is  to  be  used  in  very  inclement  weather,  the 
spar  deck,  over  the  horses,  should  be  covered.  Canvas  stretched 
over  a  secure  frame  is  better  than  boards,  as  the  latter,  in  a 
severe  storm,  might,  be  carried  away,  and  its  wreck  would  cause 
disaster  among  the  horses. 

During  heavy  weather,  horses  sometimes  become  exhausted 
and  fall.  The  best  thing  that  can  be  done  in  such  cases  is  to 
back  out  the  horse  on  each  side,  so  as  to  give  the  fallen  horse 
plenty  of  room.  The  next  horses  adjoining  are  prevented  from 
trampling  him  by  having  placed  against  them  braces  such  as 
heretofore  described.  There  should  be  several  of  these  braces 
spare  for  this  special  purpose.  The  fallen  horse  should  be  pro- 
tected from  rain  and  spray  by  a  paulin,  and  great  care  and  ten- 
derness exercised  towards  him ;  otherwise  he  is  very  liable  to 
perish.  The  horses  may  be  fed  from  nose-bags,  but  it  is  better 
to  have  for  each  one  a  small  trough,  suspended  to  the  hitching- 
bar  by  means  of  two  iron  hooks  passing  over  the  bar.  The 
troughs  are  moved  out  of  the  way  when  not  in  use.  Hay  can 
be  fed  to  them  by  tying  it  up  tightly  in  bundles  with  rope-yarn 
and  fastening  the  bundles  to  the  hitching-bar.  It  may  also  be 
fed  in  small  quantities  by  hand,  and  the  more  attention  the 
horses  receive  in  this  way  from  the  men,  the  less  fretful  and 
uneasjr  they  become. 

When  the  embarkation  takes  place  from  a  wharf,  and  the  ves- 
sel is  not  too  high,  it  is  best  to  use  gang-planks  and  lead  the 
horses  on  board.  The  gang-plank  leading  up  from  the  wharf 
to  the  gunwale  should  be  about  20  feet  long  by  10  wide,  and 
be  made  very  strong.  This  width  admits  of  its  being  used  for 
gun  carriages.  It  should  be  provided  with  ropes  at  the  corners, 
rollers,  side  rails,  and  boards  upon  the  sides  to  prevent  the 
horses  from  getting  their  feet  over  the  edges.  Another  similar 
gang-plank,  but  not  so  long,  leads  from  the  gunwale  to  the 


SLING.  329 

• 

deck,  ihe  two  being  securely  fastened  together  by  their  ropes. 
These  gang-planks  should  be  carried  by  the  vessel,  ready  for 
disembarking.  Every  provision  for  this  latter  operation  should 
be  thoroughly  looked  after  before  starting  on  the  voyage. 

When  it  is  not  practicable  lo  use  gang-planks,  the  horse*  are 
hoisted  on  board  by  means  of  a  sling  and  lifting  tackle. 

574.  Sling.  This  is  made  of  stout  web,  or  double  No.  1 
canvas.  It  is  5  feet  long  and  2  feet  wide,  secured  at  each  end 
by  a  stick  of  strong  wood  2  inches  in  diameter.  The  sides  are 
bound  with  strips  of  canvas  doubled,  thus  making  the  edges  four 
thicknesses.  Loops  of  4-inch  rope  are  attached  to  each  stick. 
(Fig.  2,  Plate  56.) 

The  loop  attached  to  one  stick  is  9  inches  long;  that  attached 
to  the  other  is  2  feet  11  inches,  and  has  an  iron  eye — 3  inches, 
inside  measurement — fixed  In  the  end.  Breast  and  breech  ropes 
(2-inch)  9  feet  long  are  fixed  to  each  side,  and  are  tied  together 
when  the  sling  has  been  put  under  the  horse.  The  slings  should 
be  tested  by  a~n  excess  of  weight.  A  donkey-engine  is  used  for 
hoisting. 

Five  men  are  required  to  slinj  a  horse  quickly  and  well.  One 
man  holds  the  head  guy,  which  is  attached  to  a  neck-collar;  two 
men,  one  on  each  side  of  the  horse,  pass  the  sling  under  his 
belly;  both  then  hold  up  the  ends  over  his  back,  passing  the 
long  loop  through  the  shorter  one  and  hooking  on  the  eye  of 
the  former  to  the  lifting  tackle,  continuing  to  hold  up  the  sling 
until  the  horse's  legs  leave  the  ground;  another  man  stands  at 
the  breast  and  fastens  the  breast-rope,  while  the  fifth  stands  at 
his  rump  and  fastens  the  breech-rope.  The  officer  superintend- 
ing commands :  HOIST  AWAY.  The  first  man  slacks  away  at 
the  guy-rope,  holding  it  just  sufficiently  taut  to  keep  the  horse's 
head  steady.  When  hoisting,  no  delay  should  be  permitted;  it 
should  be  done  in  the  shortest  time  compatible  with  safety.  At 
the  commencement,  after  a  certainty  that  all  is  right,  it  should 
be  done  rapidly,  to  raise  the  horse  off  his  feet  and  free  him  from 
surrounding  objects  before  he  has  time  to  do  any  injury  by  kick- 
ing. After  attaining  the  necessaiy  height,  he  is  carefully  and 
steadily  lowered  to  the  deck.  Care  should  be  taken  to  have  two 
or  three  careful  and  active  men  stationed  to  seize  the  horse  and 
prevent  his  plunging  until  the  slings  are  removed.  While  one 
holds  him  by  the  head-stall,  another  rapidly  unhooks  the  tackle 
purchase,  and  two  others  let  loose  the  breech  and  breast  bands, 
or  ropes.  When  the  horses  are  to  be  lowered  through  a  hatch 
to  a  deck  below,  the  combings  of  the  hatch,  as  well  as  stanchions 
about  it,  should  be  well  padded.  As  an  additional  precaution, 
a  head-collar  should  be  provided,  with  a  large  pad  on  top  to  pre- 


330  STALLS. 

■ 

vent  injury  should  the  horse  strike  his  head  against  the  deck 
beams  when  lighting  on  his  feet.  Everything  being  in  readi- 
ness and  skillfully  managed,  an  average  lot  of  one  hundred 
horses  can  be  hoisted  on  board  in  from  two  to  three  hours. 
Hatches  for  horses  must  be  at  least  10  by  10  feet. 

Allowing  1100  pounds  as  the  average  weight  of  artillery  horses 
and  150  pounds  as  that  of  men,  and  estimating  for  ten  days'  sup- 
ply of  food,  water,  and  forage,  the  total  weight  of  a  field  battery 
of  six  pieces,  fully  equipped  and  provided  for  field  service,  and 
including  two  baggage- wagons  loaded  with  camp  equipage  and 
baggage,  will  be  329,000  pounds,  or  about  165  American  tons, 
fiorses  embarked  as  described — i.  e.,  without  stalls  —  require 
each  a  space  equal  to  3.5  tons,  marine  measurement;  therefore 
about  550  tons  will  be  required  for  the  horses  alone.  It  is  thus 
seen  that  the  actual  weight  of  a  battery  forms  but  a  small  pro- 
portion of  the  shipping  tonnage  required  for  it.  The  class  of 
sea-going  steamers  usuallj'  chartered  for  transportation  service 
are  those  that  ply  between  points  along  the  sea-board.  They 
are  generally  propellers,  ai:d  vary  in  tonnage  from  one  to  two 
thousand  tons.  Owing  to  the  fact  that  a  considerable  part  of 
their  room  U  usually  taken  up  with  passenger  accommodations* 
they  are  seldom  able  to  cany  more  than  one  full  battery.  A 
steamer  of  2000  tons  burden,  with  a  free  spar  and  main  deck,  is 
capable  of  carrying  two  complete  batteries. 

575*  Stalls.  The  extensive  experience  of  the  British  Army 
during  the  Crimean  war  and  in  the  Canadian,  East  Indian,  and 
other  colonial  service,  has  enabled  the  English  to  arrive  at  great 
perfection  in  fitting  up  transports  for  horses.  The  following  is 
the  method  adopted :  Each  horse  is  provided  with  a  stall ;  these 
are  placed  in  two  rows,  one  on  each  side  of  the  ship,  with  the 
heads  of  the  horses  facing  inwards.  (Fig.  3,  Plate  56.)  The 
rear  end  of  the  stall  is  not  less  than  two  feet  from  the  side  of  the 
vessel;  three  feet  is  allowed  when  breadth  of  deck  admits  of  it. 
The  stalls  in  each  row  are  built  together,  so  as  to  be  continuous. 
They  are  6  feet  long  from  inside  of  padding  on  the  breast-piece 
to  the  inside  of  haunch-piece,  and  2  feet  2  inches  between  the 
padding  on  the  side  bales;  ten  per  cent,  are  2  inches  narrower, 
and  live  per  cent,  are  6  inches  longer. 

To  construct  the  stalls,  two  lines  of  scantling  (A  and  B)  are 
laid  down  parallel  with  the  keel  of  the  ship,  and  7  feet  5.5 
inches  apart;  the  outer  line  is  at  the  required  distance  (2  to  3- 
feet)  from  the  ship's  side ;  the  scantling  are  5  by  5  inches,  and 
are  secured  to  the  deck  by  1-inch  screw  bolts  of  wrong! it-iron. 
They  are  scored  three-fourths  of  an  inch  deep  on  the  inside,  at 
intervals  of  2  feet  6.5  inches  (from  centre  to  centre  of  score),  to  re- 


HAUNCH-PIECE — BRRA  ST-PIBCB.  33 1 

ceive  the  heels  of  the  stanchions  (C  and  D).  These  stanchions  are- 
of  scantling  the  same  as  the  stringers,  and  are  cut  to  the  exact 
height  from  deck  to  deck ;  they  rest  below  on  the  deck,  fitting 
into  the  scores  of  the  stringers;  they  are  secured  to  the  decK 
above  by  means  of  cleats  fastened  with  heavy  spikes ;  the  stan- 
chions are  secured,  in  addition,  both  above  and  below,  with  spike* 
driven  obliquely  into  them  and  the  deck;  against  the  lear  s.ide 
of  the  front  stanchions  are  placed  short  pieces  of  scantling  lE) 
for  the  purpose  of  securing  the  breast-piece  and  side  bales ;  these 
pieces  are  4  feet  long,  7  by  6  im  lies  thick,  and  of  good  strong 
wood;  in  the  top  are  two  slots  for  the  reception  of  the  ends  of 
the  breast-piece  and  side  bale;  they  are  secured  to  ihe  fiont 
stanchion  by  a  0.75-inch  bolt  at  12  inches  from  the  top;  below 
they  are  seemed  by  spikes  toed  into  the  deck  aud  by  the  floor- 
ing cut  away  to  receive  them. 

The  flooring  is  of  2-inch  plank  spiked  to  the  deck ;  the  spikes 
are  driven  so  that  they  are  covered  by  the  cross- bat  tens* ;  the 
planks  are  laid  lengthwise,  nor.  across  the  stall,  extending  from. 
the  front  scantling  (A)  to  within  7  inches  of  the  rear  one  (B;% 
with  intervals  between  them  of  0.75  inch.  The  upper  edges  are 
beveled  off"  half  an  inch.  These  intervals  are  for  the  purpose  of 
drainage. 

Six  battens  (F  F  F)  of  hard  wood,  2  by  3  inches,  are  laid  across 
the  planks,  beginning  0  inches  from  the  rear  ends  of  the  planks  ; 
the  others  at  intervals  of  12  inches.  These  battens  are  contin- 
uous, running  the  entire  length  of  the  stalls;  scantling  5  inches 
deep  by  3  inches  wide  and  G  feet  9  inches  long  are  laid  along 
each  side  of  the  stall,  fitting  tightly  between  the  front  and  rear 
stanchions,  and  scored  underneath  to  fit.  on  the  cross-battens; 
each  is  secured  by  spikes  driven  through  the  floor-planks  into 
the  deck.  These  pieces  are  for  the  purpose  of  holding  the  cross- 
battens  beyond  any  possibility  of  breaking  away. 

To  facilitate  cleaning  the  stalls  without  at  the  same  time 
weakening  the  construction,  these  pieces  are  sawed  through  at  6- 
inches  from  the  hind  stanchions,  aud  a  strap-hinge  fastened  on 
top  so  that  the  short  end  can  be  thrown  back  when  it  is  neces- 
sary to  sweep  the  stalls.  A  clear  drainage  space  is  thus  left  along 
the  whole  line  of  stalls. 

The  haunch-piece  (G)  is  a  continuous  piece  of  scantling  9  inches 
deep  by  5  inches  thick;  it  is  secured  to  the  inside  of  the  rear 
stanchions  by  bolts,  with  its  top  3  feet  8  inches  above  the  floor- 
planks;  the  top  and  inside  surface  are  rounded  off  and  smoothed 
so  as  not  to  chafe  the  horse ;  opposite  each  stanchion  a  mortise 
is  cut  in  the  haunch-piece  for  the  reception  of  the  side  bale. 

Tlie  breast-piece  (EL)  is  of  hard  wood  6  inches  thick  by  & 


332  HORSE-HAMMOCK. 

Inches  deep;  it  is  hollowed  ont  in  the  middle  and  rounded  so  as 
to  confonn  to  the  breast  of  the  horse.  The  breast-piece  of  each 
stall  is  removable;  its  ends,  cut  to  the  proper  shape,  rest  in  the 
slots  of  the  short  uprights  (E) ;  a  wooden  key  (J),  turning  on  an 
iron  bolt,  secures  both  the  breast-piece  and  side  bale  from  lift- 
ing out;  the  upper  edge  of  the  breast-piece  is  3  feet  11  inches 
above  the  floor-planks. 

The  side  bales  are  of  9  by  3  inch  wood  ;  in  front,  they  are  on 
a  level  with  the  breast-piece;  in  rear,  with  the  haunch-piece; 
behind,  they  are  tenoned  into  the  haunch-piece;  in  front,  they 
slide  into  the  slot  in  the  short  uprights,  being  kept  there  by 
the  key  (J);  they  are  smoothed  off  and  padded  with  sheepskin 
long  in  wool,  put  on  double.  The  same  kind  of  padding  is  used 
for  the  breast-piece ;  none  is  put  on  the  haunch-piece.  About 
15  per  cent,  of  .^pare  side  bales  are  provided. 

The  manger  (L)  is  made  of  inch  boards  18  inches  long,  15  inches 
wide  at  top  and  12  at  bottom,  and  9  inches  deep,  inside  meas- 
urements; it  is  lined  with  tin  or  zinc;  an  iron  band  passes  un- 
derneath and  up  over  the  ends,  terminating  in  two  holes,  by 
means  of  which  the  manger  is  suspended  to  two  iron  pins  fixed 
to  the  front  stanchions. 

Zinc  or  iron  hooping  is  nailed  around  the  stanchions  wher- 
ever horses  can  get  at  them  to  gnaw. 

The  horse's  head  is  secured  by  means  of  a  head-halter,  the 
strap  of  which  is  fastened  to  a  ring  attached  to  the  front  stan- 
chion. It  is  best  to  have  two  straps  to  each  halter,  one  fastened 
to  each  side. 

Kicking  boards  are  provided  for  such  horses  as  require  them  ; 
they  are  attached  to  the  inside  of  the  rear  stanchions  with 
screws. 

Four  pulley  blocks  for  the  ropes  of  the  horse-hammocks  are 
placed,  two  over  each  side  bale,  one  at  12  inches  from  the  front 
stanchion  and  the  other  2  feet  3  inches  from  the  hind  stanchion. 
Those  in  front  are  double,  the  hind  ones  single.  These  blocks 
are  screwed  to  the  deck  above. 

576.  The  horse-hammock  is  similar  to  the  sling  before  de- 
scribed, except  that  the  sticks  at  the  ends  project  on  each  side 
S  inches  beyond  the  canvas.  A  2-inch  rope  30  feet  long  is  passed 
around  each  stick  in  a  single  clove  hitch,  (Fig.  4,  Plate  56,) 
the  hitch  being  secured  at  its  crossing  with  spun-yarn.  The  end 
of  the  rope  from  the  rear  side  of  the  hammock  is  3.5  feet  longer 
than  that  from  the  front  side,  and  passes  up  through  the  rear 
t)lock  and  over  one  of  the  sheaves  of  the  front  block;  the  front 
end  of  the  rope  passes  over  the  other  sheave;  both  are  carried 
iorward  and  secured  by  an  iron  belaying  cleat  fastened  to  the 


CARE   OF   HORSES   AT   SEA.  33S 

i 

I  deck  above.     The  hammock  is  kept  in  position  on  the,  horse  by 

|  a  breast-band  40  inches  Jong  and  a  breeching  56  inches  long  and 

I  4  inches  wide.    These  straps  are  held  in  position  by  a  whher 

!  and  a  croup  strap,  both  of  which  are  united  along  the  back  by 

|  another  strap.     All  of  these  straps  are  made  of  canvas  or  strong 

i  webbing,  and  secured  with  buckles. 

;  There  must  be  ten  per  cent,  of  spare  stalls,  and  there  should 

be  a  loose  box  constructed  near  a  hatchway  to  admit  of  a  .sick 
horse  tying  down.  Each  stall  is  numbered,  the  side  bales,  breast- 
pieces  and  mangers  being  marked  with  the  number  of  the  stall 
to  which  they  belong. 

It  is  advisable  to  have  as  many  stalls  on  the  upper  deck  as 
possible,  unless  extremely  bad  weather  is  anticipated.  They 
are  constructed  like  tho*e  already  described,  except  that  they 
are  covered  in  above  by  a  sloping  roof  laid  upon  rafters  connect- 
ing the  stanchions. 

The  Himalaya,  of  3500  tons  burden,  fitted  up  in  the  manner 
described,  successfully  carried,  during  the  Crimean  war,  3000 
horses  with  a  loss  of  only  three.  They  were  arranged  :  200  ou 
the  spar  deck  ;  130  on  the  main  deck;  50  on  the  orlop  deck, — 
making  380  carried  at  a  trip. 

On  the  spar  deck,  the  platforms  of  the  stalls  were  placed  2 
inches  above  the  deck  to  admit  of  cleaning,  draining,  and  wash- 
ing. The  platform  was  in  sections  of  two  stalls  each,  and  could 
be  shifted. 

The  horses,  when  put  aboard,  were  led,  the  first  one  to  the 
most  distant  stall;  then  the  side  bale  was  put  in  place,  another 
horse  brought  and  placed  alongside,  and  soon  until  the  embark- 
ing was  completed. 

When  a  horse  becomes  sick  or  disabled  at  sea,  and  it  is  found 
necessary  to  move  him  from  his  stall,  the  feed-box  is  unhooked, 
the  breast-piece  unshipped,  and  he  is  taken  into  the  narrow 
passage  or  gangway  separating  the  two  rows  of  stalls. 

577.  Care  of  horses  at  sea.  For  the  first  few  days  on  ship- 
board food  is  to  be  given  rather  sparingly,  and  bran  is  to  form 
a  large  portion  of  it;  but  after  the  horse  becomes  accustomed  to- 
his  new  situation  and  his  appetite  increases,  he  is  to  be  more  lib- 
erally fed.  A  bran  mash,  or  oats  and  bran  mixed,  is  to  be  given 
to  him  every  other  day. 

The  spare  stalls  admit  of  the  horses  being  shifted,  rubbed 
down,  their  feet  washed,  and  the  stalls  cleaned  out  every  day 
when  the  weather  permits.  Hand-rubbing  the  legs  is  of  the 
greatest  consequence  to  the  comfort  and  well-being  of  the  horse,, 
and  is  to  be  practiced,  if  possible,  every  day,  or  whenever  the 
horses  change  stalls. 


334  CARE   OP   HORSES   AT   SEA. 

Horses  are  to  be  slung  in  smooth  weather,  and  allowed  to 
-stand  on  their  legs  in  rough  and  stormy  weather.  In  smooth 
-weather,  they  will  rest  their  legs  and  feet  by  throwing  their 
whole  weight  into  the  slings.  To  sling  a  horse  in  rough  weather, 
whereby  he  is  taken  off  his  feet,  would  only  have  the  effect  of 
knocking  him  about  with  the  roll  of  the  ship.  Horses  standing, 
accommodate  themselves  to  the  motion  of  the  vessel.  They  are 
not  to  be  placed  in  the  horse-hammock  until  they  have  been  at 
sea  for  a  week,  as  some  would  only  be  made  uueasjr  by  the  at- 
tempt to  do  so. 

The  hammock  is  to  be  placed  around  the  centre  of  the  horse's 
Tielly,  and  then  the  breast-band  and  breeching  fastened  to  the 
required  length  and  degree  of  tightness.  When  everything  is  in 
readiness,  and  not  before,  the  horse  is  quickly  raised  until  all,  or 
nearly  all,  of  his  weight  is  off  his  legs.  He  will  very  soon  learn 
the  relief  the  hammock  affords  him,  and  will  not  be  slow  in 
availing  himself  of  it  by  throwing  his  weight  into  it.  With  some 
horses  it  is  necessary  to  use  great  quickness  in  making  the  ropes 
fast  before  they  throw  their  whole  weight  into  the  hammock. 

When  the  horses  are  between  decks,  too  much  attention  can- 
not be  paid  to  the  constant  trimming  of  the  wind-sails,  so  a*  to 
insure  plenty  of  fresh  air.  The  wind-sails  should  be  well  for- 
ward, and  extend  down  to  within  two  or  three  feet  of  the  deck. 
When  a  horse  between  decks  becomes  ill,  and  the  weather  is  at 
all  tine,  he  should  be  removed  to  the  upper  deck,  where  the  fresh 
air  and  change  will  probably  soon  bring  him  right  again. 

Besides  the  ordinary  grooming  uiensils  for  stable  service,  there 
should  be  a  plentiful  supply  of  stable  brooms,  hoes,  and  shovels 
for  cleaning  out  the  stalls,  and  baskets  or  other  light  vessels  for 
removing  the  manure.  The  ship  must  be  well  lighted  and  the 
guards  attentive ;  sea-sick  men  must  not  be  intrusted  with  this 
important  duty. 

Disinfectants,  such  as  chloride  of  lime  and  of  zinc,  copperas, 
powdeied  gypsum,  &c,  should  be  freely  used,  and  upon  embark- 
ing the  artillery  commander  will  see  that  they  are  supplied. 

The  feed-troughs  and  nostrils  of  the  horses  are  washed  every 
morning  and  evening  with  diluted  vinegar. 

Water  is  allowed  at  the  rate  of  six  gallons  a  day  per  horse  and 
one  gallon  per  man. 

During  the  voyage  the  artillery  commander  will  make  it  his 
-especial  study  to  act  in  harmony  with  the  master  of  the  vessel. 
There  must  of  necessity  be  divided  authority  and  responsibility. 
Order  and  neatness  among  the  men  and  cleanliness  with  the 
■horses  are  to  be  looked  after  by  the  commander  of  the  troops. 
In  attending  to  these  duties,  care  will  be  observed  not  to  inter- 


DISEMBARKING.  335 

fere  needlessly  with  the  duties  of  the  crew,  nor  with  the  belong- 
ings of  the  ship. 

Officers  are  always  to  be  furnished  with  cabin  accommodations 
And  the  men  with  proper  messing  arrangements.  This  should 
be  specified  in  the  charter,  and  should  be  clearly  understood  by 
all  parties  previous  to  setting  out  on  the  voyage. 

The  fitting-up  of  the  vessel  is  generally  done  by  the  Quarter- 
master's Department,  but  the  commander  of  the  artillery  to  be 
embarked  will,  as  the  one  most  concerned,  give  his  special  at- 
tention to  see  that  the  work  is  thorough  and  complete. 

Mjis te i-8  and  owners  of  vessels  always  dislike  to  have  them 
"bored,  spiked,  and  bolted  Into  in  the  manner  necessary  for  fit- 
ting them  up  for  artillery  transport?.  To  remove  all  causes  of 
-complaints  and  objections,  and  of  contentions  between  the 
master  of  the  vessel  and  the  officer  embarking  his  troops,  arising 
on  this  score,  the  charter  party  should  clearly  specify  the  extent 
and  nature  of  the  work  required  to  be  done. 

When  an  expedition  of  considerable  size  is  to  start  out.  a 
steamer  suitable  for  the  purpose  should  be  converted  into  a 
workshop,  containing  forges  capable  of  doing  heavy  work,  to- 
gether with  carpenter  and  shipwright  facilities.  She  should  carry 
a  plentiful  supply  of  such  material  as  will  probably  be  required. 

A  steam  pile-driver  should  always  form  part  of  the  outfit  of 
an  expedition. 

578.  Disembarking.  When  this  can  be  done  at  a  wharf,  it 
is  simply  the  reverse  operation  of  embarking. 

When  wharf  accommodations  are  not  available,  arrangements 
will  have  to  be  made  for  transferring  the  men,  horses,  and 
material  from  the  vessel  to  the  shore. 

An  army  or  other  considerable  body  of  troops  embarked  for 
an  expedition,  to  be  landed  under  such  circumstances,  will  be 
provided  with  general  means  for  disembarking,  and  the  artil- 
lery, which  usually  constitutes  an  important  feature  of  the  out- 
fit, shares  with  the  rest  in  these  general  arrangements;  but, 
owing  to  its  nature,  much  of  a  special  character  is  required  for 
it,  demanding  the  most  careful  consideration  and  attention  from 
artillery  officers. 

Such  expeditions  usually  embark  at  sea-ports  where  there  are 
accommodations  that  make  the  operation  comparatively  simple 
and  easy,  and  for  this  reason  the  many  preparations  necessary 
for  landing  on  an  open  shore  are  apt  to  be  overlooked,  or  to  be 
inadequately  provided  for.  It  becomes  the  especial  province  of 
•the  artillery  commander  to  look  out  for  this,  and  to  give  his 
advice  and  make  his  wants  known  to  the  army  commander,  so 
that  the  latter  may  cause  proper  provision  to  be  made. 


336  DISEMBARKING. 

The  following  method  for  the  disembarkation  of  an  army 
corps  proved  successful  during  the  war  of  the  rebellion,  and 
the  same,  or  some  modification  of  it,  will  apply  in  every  case. 

The  essential  articles  for  forming  a  landing-place  were,  sev- 
eral canal-barges ;  a  number  of  pontoon -boats,  with  balks,  chess, 
oars,  anchors,  &c,  complete;  a  number  of  gang-planks;  a  plen- 
tiful supply  of  lumber,  and  the  necessary  amount  of  ground 
tackle,  cordage,  and  tools. 

The  canal-barges  were  about  14  feet  wide  and  70  to  80  feet 
long,  (drawing,  when  loaded,  5  feet  of  water;  when  light,  2  feet,) 
and  of  about  80  tons  burden. 

The  gang-planks  were  from  12  to  30  feet  long  and  10  feet  wide, 
and  very  strong;  ropes  were  attached  to  their  corners,  and  the 
larger  ones  furnished  with  rollers. 

By  la  hing  two  of  the  canal-barges  together,  placing  the  boats 
some  12  feet  apart,  and  throwing  a  false  or  additional  deck  over 
the  whole,  a  platform  was  formed  about  40  feet  wide  and  45 
feet  long,  capable  of  holding  all  the  pieces  and  caissons  of  a  six- 
gun  field  battery,  or  from  forty  to  fifty  horses.  This  boat  or 
raft,  when  thus  loaded,  drew  about  4  feet  of  water. 

Several  of  these  rafts  were  prepared  for  the  purpose  of  form- 
ing a  wharf-head,  alongside  of  which  vessels  could  lie  and  dis- 
charge. 

From  this  wharf-head  to  the  shore  a  pontoon-bridge  was  con- 
structed.    (Fig.  5,  Plate  56.) 

The  wharf-head  was  formed  by  bringing  up  as  near  the  shore 
as  possible  one  of  the  lightest  of  the  double  canal-boats  just  de- 
scribed ;  this  was  securely  moored  in  proper  position  at  high 
water,  when  it  at  once  grounded.  Outside  of  and  parallel  to  it, 
at  a  distance  of  some  twenty  feet,  was  placed,  and  in  like  man- 
ner securely  moored,  the  double  canal-boat  next  heaviest  in 
draught  of  water ;  the  space  between  the  two  being  bridged  by- 
one  of  the  largest  gang-planks. 

In  the  same  manner  was  placed  a  third  double  canal-boat, 
alongside  of  which  was  moored  a  light  draught  steamer,  which 
formed  the  pier-head  to  the  wharf  and  secured  depth  of  water 
sufficient  for  the  transports  to  come  alongside. 

From  the  double  canal  boat  first  put  in  position,  a  roadway 
to  the  shore  was  made  by  constructing  a  pontoon-bridge  in  the 
usual  m  inner. 

The  operation  of  disembarking  consisted  in  bringing  the 
transports  alongside  of  the  wharf-head,  placing  a  gang-plank 
from  the  deck  to  the  gunwale,  and  another  from  the  gunwale 
to  the  wharf-head.  Over  these  gang-planks  the  horses  were  led 
and  taken  ashore.   The  guns,  caissons,  and  other  carriages  were 


DISEMBARKING  337 

nm  down  the  gang-plank  and  over  the  bridge  by  hand.  In  this 
way  b«it  two  or  three  hours  were  consumed  in  disembarking  an 
entire  battery. 

For  disembarking  artillery  by  thia  method,  or  indeed  by  any 
method,  smooth  or  comparatively  smooth  water  is  a  sine  qua 
non.  Infantry,  and  even  artillery  materi.il,  may  be  landed  with 
small  boats  or  lighters  through  a  heavy  surf,  but  a  smooth  sea  is 
required  for  hordes. 

When  it  is  not  considered  expedient  to  construct  a  wharf- 
head  and  bridge  as  just  described,  and  the  water  near  shore  is 
of  sufficient  depth,  double  canal-boats  may  be  u.»ed  for  rafts  to 
disembark  both  horses  and  material.  The" rafts  must  have  rail- 
ing around  them  ;  this  should  be  strong,  the  stanchions  extend- 
ing into  the  boats  and  secured  throughout  with  bolts  and  nuts. 
The  horses  are  loaded  from  the  vessel  onto  the  raft  either  by 
means  of  gang-planks  or  by  slinging  them.  The  raft  is  towed  to 
the  shore  by  small  boats  or,  better,  by  a  small  steam-tug;  a 
gang-plank  is  run  out  and  the  horses  led  ashore.  The  guns  and 
caissons  are  brought  ashore  in  the  same  manner. 

When  canal-barges  are  not  to  be  had,  small  coasting  schooners 
may,  by  removing  their  deck  hamper,  be  used  instead.  Large 
decked-over  scows,  such  as  are  to  be  found  in  sea-port  towns, 
make  excellent  rafts.  When  the  distance  from  the  vessel  to  the 
shore  does  not  exceed  1000  yards  or  thereabouts,  a  warp-line 
may  be  used  for  bringing  back  and  forth  the  raft.  Every  exer- 
tion should  be  made  to  erect  a  wharf,  rough  and  temporary 
though  it  be,  using  for  the  purpose  any  kind  of  boats  or  scows 
that  can  be  obtained.  It  may  sometimes  be  advisable  to  sacri- 
fice a  ship  for  the  purpose  of  forming  a  wharf-head,  by  scuttling 
and  sinking  her  in  such  depth  of  water  as  to  leave  her  spar  deck 
three  or  four  feet  above  high  water.  With  a  sandy  or  muddy 
bottom,  a  ship  might  be  sunk  by  loading  her  down  until  she 
rests  firmly  on  the  bottom.  If  the  weather  is  calm  she  will 
suffer  no  great  injuty,  and  can  be  floated  off  when  no  longer 
required. 

The  business  of  constructing  rafts  and  wharfs  as  described, 
belongs,  as  a  general  rule,  to  the  engineers;  but  should  the 
artillery  commander  of  an  expedition  anticipate,  even  in  the 
remotest  degree,  a  failure  to  provide  the  requisite  means  for 
disembarking,  it  becomes  his  duty  to  look  after  it,  and  he  can- 
not be  too  zealous  in  doing  so.  The  best  plan  under  such  cir- 
cumstances is  for  each  transport  to  carry  along  with  it  ail  outfit 
capable  of  discharging  its  cargo. 

The  most  useful  boat  for  lightering,  that  can  be  carried,  is  the 
wooden  pontoon,  such  as  is  used  for  military  bridges.    It  is  31 

22 


338  DISEMBARKING. 

feet  long,  5.5  feet  wide  at  top,  4.5  feet  wide  at  bottom,  and  2.6 
feet  deep.  Besides  the  three  men  required  for  managing  it,  it 
is  capable  of  carrying  40  infantrymen  with  their  arms  and  knap- 
sacks, and  it  will  very  readily  carry  six  horses.  It  is  better, 
however,  when  disembarking  artillery,  to  form  rafts  by  uniting' 
two  boats  in  the  usual  manner  for  a  bridge,  except  that  a  double 
number  of  balks  should  be  used.  The  platform  may  be  twice 
the  width  allowed  for  the  roadway  of  a  bridge ;  thus  formed,  it 
will  be  24  feet  long  by  20  wide,  and  capable  of  carrying  two 
field-pieces  and  caissons  complete,  or  from  15  to  20  horses. 

The  platform  must  be  provided  with  a  secure  railing.  All  of 
the  parts  should  be  fitted  and  numbered  previous  to  embarking, 
and  the  men  practiced  until  they  become  skillful  in  putting  the 
raft  together.  In  consequence  of  the  lowness  of  this  platform, 
it  is  impracticable  to  use  gang-planks  from  the  decks  of  ordinary 
vessels,  and  the  horses  have  therefore  to  be  lowered  onto  it  by 
slinging.  A  warp-line  to  the  shore  is  the  best  means  of  taking 
it  back  and  forth. 

Each  transport  should  carry  four  pontoon -boats  and  all  the 
equipment  for  two  rafts.  If  there  is  not  sufficient  room  on  deck 
for  the  boats,  they  may  be  carried  stowed  flat  to  the  sides  of  the 
ship,  bottom  outwards,  resting  on  strong  solid  chocks  bolted  to 
the  wales.  A  strong  parbuckle-sling  passes  around  each,  with 
which  it  is  hoisted  into  place  by  the.  yard  and  stay  purchases, 
and  secured  by  lashings ;  by  the  same  means  it  is  lowered  into 
the  water. 

With  several  transports,  each  carrying  the  above-described  out- 
fit, it  is  generally  practicable,  by  combining  all,  to  form  a  bridge. 
Suitable  vessels  can  nearly  always  be  obtained  for  forming  the 
wharf-head. 

When  there  are  several  transports  unloading  at  the  same  time, 
conspicuous  and  well-understood  signal  marks  must  be  placed  op- 
posit^  each,  on  the  beach,  so  that  it  may  be  known  to  what  points 
to  direct  the  boats  and  rafts  without  confusion.  A  strong  party 
for  each  should  be  on  shore  to  secure  the  rafts  upon  touching,  to 
haul  up  the  gun3  and  caissons,  and  to  take  care  of  the  horses. 

Unless  there  is  some  special  reason  to  the  contrary,  horses 
will  always  be  lauded  first.  This  gives  them  an  opportunity  of 
resting  and  recovering  from  the  trip  while  the  material  is  being 
landed. 

When  pontoon -boats  are  not  available,  scows,  fishing-smacks, 
or  other  small  craft  must  be  collected  and  used  instead. 

As  a  last  resort,  the  horses  may  be  swum  ashore,  and  the  mate* 
rial  landed  in  the  ship's  boats, — a  very  tedious  operation.  The 
horses  are  lowered  over  the  side  by  slinging;  a  boat  must  be  in 


DISEMBARKING.  839 

Attendance  below  to  unhook  the  fall  and  clear  the  sling.  The  sling 
for  this  purpose  must  be  without  breast  or  breech  strap*,  and  the 
loops  should  be  closed  up  with  canvas,  so  that  there  ma}'  be  no  pos- 
sibility of  the  horse  getting  his  legs  entangled  in  any  part  of  it. 
A  very  slight  embarrassment  of  this  kind  will  cause  the  horse  to 
•drown.  A  man  in  the  small  boat  takes  him  by  the  halter  and, 
conducting  him  a  short  distance,  gives  him  the  proper  direction 
to  the  shore  ;  without  this  precaution,  horses  sometimes  become 
bewildered  and  swim  around  the  vessel  until  exhausted.  Ho  scs 
will  very  readily  swim,  in  smooth  water,  half  a  mile.  When 
the  deck  of  the  vessel  is  low,  say  not  over  ten  feet,  and  there  is 
a  gangway,  the  horses  may  be  backed  off  into  the  water  without 
slinging.  This  method  should  not,  however,  be  resorted  to  if  it 
-can  possibly  avoided;  it  is  liable  to  strain  and  injure  the  animal, 
and  will  ever  after  make  him  timid  and  shy  about  taking  the 
water  when  it  is  necessary  to  cross  streams  on  the  march. 

Siege  guns  are  embarked  and  disembarked  in  the  same  general 
manner  as  light  lield-pieces.  When  gang-plank*  are  used,  they 
are  hauled  up  or  let  down  bjr  means  of  tackle.  When  embarking 
from  a  wharf  or  raft  without  gang-planks,  the  piece  is  run  with 
its  carriage  under  the  ship's  tackle ;  the  gun  is  slung  and  hoisted 
aboard  ami  lowered  onto  the  deck  or  into  the  hold.  In  disem- 
barking, the  carriage  is  first  put  upon  the  wharf  or  raft  under 
the  ship's  tackle,  and  the  piece  then  lowered  onto  it. 

When  it  is  necessary  to  land  heavy  guns  by  means  of  lighters, 
or  from  small  vessels,  the  latter  may  be  beached  at  high  tide ; 
the  pieces  are  raised  by  blocking  and  skids  until  they  can  be 
rolled  down  two  inclined  skids  from  the  vessel  to  the  beach, 
where  they  are  received  upon  skids  or  blocks  of  sufficient  size  to 
prevent  them  from  burying  themselves  in  the  sand.  At  low 
•tide  they  are  removed  from  the  beach. 

Sieges,  and  similar  operations  calling  for  the  use  of  the 
heavier  classes  of  ordnance,  are  usually  of  such  a  protracted 
nature  as  to  allow  of  substantial  wharves  being  constructed,  and 
cranes,  derricks,  and  shears  provided  for  unloading  weighty 
material.  It  is  but  loss  of  time  and  labor,  often  ending  in  fail- 
ure, to  proceed  with  imperfect  arrangements  of  this  kind.  It  is 
the  duty  of  the  artillery  commander  to  study  the  situation  and 
see  that  proper  facilities  are  prepared.  Such  preparations  re- 
quire considerable  time  to  make,  and  he  should  therefore  antici- 
pate tlie  probable  wants  of  the  service  in  tins  direction,  and  not 
wait  until  the  vessels  carrying  the  material  arrive,  or  the  demand 
for  it  becomes  urgent. 

5*79*  The  disembarkation  of  an  army  most  be  considered 
cinder  two  heads :  1st.  When  made  without  any  chance  of  Inter- 


340  DISEMBARKING. 

ruption  from  an  enemy ;  2d.   When  made  in  presence  of  an 
enemy,  or  where  an  attack  is  possible. 

So  far  as  artillery  is  concerned,  the  first  of  these  conditions 
has  been  discussed  in  the  foregoing  paragraphs. 

With  regard  to  the  latter,  all  questions,  political,  strategical, 
or  otherwise,  entering  into  the  object  of  the  expedition,  having 
been  settled  by  the  proper  authorities,  and  the  army  for  carry  ing 
it  out  having  been  organized,  embarked,  and  the  transports 
arrived  within  the  general  limits  of  the  field  of  operations,  the 
first  thing  to  be  decided  upon  is  the  exact  place  or  places  where 
the  various  parts  of  the  command  are  to  be  put  ashore.  Many 
local  circumstances  will  influence  this  decision ;  among  the  most 
important  of  which  will  be  to  secure  good  anchorage  and  depth 
of  water  near  the  shore,  a  general  configuration  of  ground  ia 
front  which  will  admit  of  its  being  swept  by  the  fire  of  the  fleet, 
a  lirm  and  commodious  beach,  and  freedom  from  prevailing  winds 
or  currents  which  may  interrupt  the  disembarkation. 

The  fire  of  the  fleet  must  clear  the  country  in  front.  The  in- 
fantry is  first  landed  and  pushed  out  sufficiently  far  to  keep  the 
enemy  beyond  cannon  range  of  the  landing-place;  here  it  in- 
trenches itself,  forming  a  tUe-de-pont  around  the  landing. 

Meanwhile  preparations  will  be  made  for  lauding  the  batteries. 
All  the  boat-rafts  will  be  put  together,  and  if  a  wharf-head  and 
floating  bridge  is  to  be  constructed  it  will  be  commenced  at  once. 
Steam-tugs  must  be  in  attendance  for  towing  the  rafts,  carrying 
orders,  and  other  miscellaneous  duties.  The  artillery  commander 
designates  the  order  in  which  the  batteries  are  to  disembark,  and 
will  see  that  the  transports  take  proper  positions  for  effecting 
this  without  causing  intervals  of  unnecessary  delay. 

If  the  attacks  af  the  enemy  are  formidable  and  persistent,  de- 
manding the  immediate  service  of  artillery,  the  guns  of  several 
or  of  all  the  batteries  may  be  landed  without  their  horses,  and 
taken  to  positions  on  the  line  by  hand,  or  by  the  horses  of  one 
of  the  batteries  landed  for  that  special  purpose.  The  cannon- 
eers will  accompany  their  guns. 

If  the  resistance  of  the  enemy  cannot  be  overcome  at  this 
period,  the  expedition  is  a  failure,  and  the  army  will  have  to  be 
reembarked.  To  accomplish  this  a  strong  defensive  work  should 
be  constructed,  and  well  armed  with  such  artillery  as  may  be 
required. 

The  remainder  of  the  disembarked  artillery  is  next  put  aboard 
the  transports;  afterwards  the  infantry  and,  if  possible,  all  the 
artillery.  The  fire  of  the  fleet  should  cover  the  reembarkation, 
and  keep  the  enemy  at  such  distance  that  he  will  not  be  able 
to  use  his  artillery  upon  the  transports  or  the  place  of  landing. 


WEIGHT   OF   TROOPS   ON   BRIDGES.  341 

When  the  expeditou  is  large  and  the  number  of  transports, 
store-ships,  &c,  great,  the  worst  of  confusion  will  arise  unless 
some  system  of  marking  and  distinguishing  them  is  adopted. 
The  best  method  is  for  each  one  to  carry,  instead  of  her  own 
burgee,  the  distinguishing  flag  of  the  corps  to  which  the  troops 
on  board  belong.  This  will  show  at  a  glance  whether  they  are 
infantry,  artillery,  or  cavalry,  and  to  what  corps,  division,  and 
brigade  they  belong.  Besides  this,  each  vessel  should  have  a 
number  painted,  as  large  as  possible,  on  each  quarter.  When 
embarking,  a  memorandum  is  kept  and  furnished  to  command- 
ing and  staff  officers  showing  what  troops  are  on  board  of  each 
transport. 

The  chief-of-transports,  who  should  be  a  quartermaster  select- 
ed for  his  practical  capacity  in  such  business,  designates  the 
anchorage-ground  for  each  part  of  the  command,  and  sees  that 
they  move  up  at  the  proper  time  and  in  the  required  order  to 
the  place  of  debarkation.  It  is  with  him  that  the  artillery  com- 
mander communicates  in  reference  to  the  movements  of  the 
artillery  transports. 

When  boats  are  to  be  used  either  for  lightering,  rafting,  or 
bridging,  it  is  important  to  know  their  sustaining  capacity. 
With  small  craft,  this  is  best  ascertained  by  calculating  the  area 
of  several  cross-sections,  from  which  a  close  approximation  of 
the  cubic  contents  in  feet  is  obtained ;  this,  multiplied  by  62.5, 
gives  the  weight  in  pounds  of  the  displaced  water. 

If  the  boat  can  be  put  in  the  water,  the  operation  is  simplified 
and  made  more  accurate  by  calculating  the  volume  of  that  part 
between  the  water-line  when  the  boat,  is  empty  and  the  line  to 
which  it  can  be  safely  sunk  when  loaded. 

When  boats  of  different  sizes  are  to  be  used  in  a  bridge,  the 
largest  should  be  where  the  current  is  swiftest,  so  as  to  have 
there  the  greatest  space  possible  between  the  boats.  Anchors 
for  ordinary  ships'  boats  should  weigh  from  50  to  100  pounds; 
for  regulation  pontoons,  they  should  weigh  150  or  200  pounds. 

The  length  of  the  cable  should  always  be  at  least  ten  times 
the  depth  of  water  in  which  the  boat  is  anchored.  The  anchor 
should  be  taken  out  in  a  boat  and  dropped  over  at  the  required 
spot. 

Weight  brought  on  a  bridge  by  the  passage  of  troops.  Infantry 
marching  by  fours  cause  a  load  of  225  pounds  for  each  lineal  foot 
of  roadway.  When  crowded  by  a  check  in  front,  the  load  is  in- 
creased to  about  550  pounds. 

Cavalry  in  column  of  twos,  each  man  and  horse  weighing 
about  1400  pounds,  and  occupying  12  feet  of  bridge,  cause  a 


842  WEIGHT  OF  TROOPS   ON   BRIDGES. 

load  of  about  230  pounds  per  lineal  foot  of  roadway.    When 
crowded  by  a  check,  this  is  increased  to  about  350  pounds. 

When  artillery  carriages  cross  a  bridge,  the  weight  is  not 
equally  distributed.  With  the  carriages  of  light  field  batteries, 
the  weight  is  about  400  pounds  per  lineal  foot.  The  4.5-inch 
siege  guu  and  carriage,  equipped  for  traveling,  weighs  7400* 
pounds,  and  lias  a  distance  of  8  feet  between  bearing  parts  of 
hind  and  fore  wheels,  giving  925  pounds  per  lineal  foot  of 
bridge.  The  100-pounder  Parrott,  carried  on  a  mortar- wagou, 
gives  1737  pounds  per  lineal  feet. 

A  10-inch  siege  mortar  mounted  on  its  carriage  and  carried 
on  a  mortar-wagon  causes  a  load  of  800  pounds  per  lineal  foot* 

To  each  running  foot  of  bridge  must  be  added  about  100 
pounds  as  weight  of  superstructure. 

When  heavy  carriages  are  to  be  crossed,  a  substantial  tram- 
way made  of  long  way-planks  should  be  laid,  and  the  carriages 
moved  on  it  by  hand. 

In  constructing  a  bridge  with  ordinary  boats,  great  care  must 
be  observed  not  to  allow  the  balks  to  rest  on  the  gunwales; 
they  must  be  supported  from  the  middle  of  the  boat. 

Ice^  when  from  3  to  4  inches  thick,  will  sustain  infantry  march- 
ing in  single  file.  With  a  thickness  of  4.5  inches,  cavalry  and 
light  guns  cau  pass  over;  with  6  inches,  heavy  field-pieces ;  8 
inches  will  support  siege  guns,  but,  for  greater  security,  the 
wheels  should  be  locked  and  secured  upon  way-planks  which 
slide  upon  the  ice,  the  pieces  being  moved  by  hand. 

In  very  cold  weather  the  thickness  of  the  ice  may  be  increased 
by  covering  it  with  a  layer  of  straw  or  brush  and  throwing* 
water  over  it,  or  two  rows  of  logs  may  be  laid  at  a  distance 
apart  equal  to  the  width  of  the  roadway ;  a  layer  of  earth  is 
spread  between  them  and  water  thrown  on  and  allowed  to 
freeze.  This  operation  is  repeated  until  a  solid  roadway  i& 
formed. 

Ice,  when  very  thick,  and  therefore  difficult  to  remove,  may 
be  broken  up  by  charges  of  powder  in  water-tight  cans  or  bags, 
fixed  underneath  or  placed  in  holes  bored  in  it.  Charges  of 
from  five  to  ten  pounds  of  powder  placed  in  ice  two  feet  thick 
will  break  up  an  area  twenty  feet  in  diameter.  Eight  ounces 
of  dynamite  will  produce  a  like  result. 


$«rt  »\xth. 


HARBOR  DEFENSES. 

690.  The  entrance  to  a  harbor  may  be  considered,  and  Is  In 
fact,  a  defile,  the  defense  of  which  follows  the  rules  applicable  to 
defiles  generally. 

The  means  usually  employed  to  prevent  the  passage  of  hostile 
ships  are  divided  into  three  classes,  viz.:  1st.  Forts  and  land  bat- 
teries; 2d.  Submarine  mines ;  3d.  Floating  defenses. 

The  latter  class,  which  includes  monitors  and  offensive  torpe- 
does, is  under  the  exclusive  control  of  the  Navy. 

Submarine  mines  will  be  considered  further  on. 

The  first  class  is  the  one  now  to  be  considered,  and  this  con- 
sideration of  it  is  intended  to  refer  especially  to  the  use  of  guns 
on  laud  against  armored  ships. 

581.  Position  of  batteries.  Whenever  practicable,  batteries 
should  be  well  strung  out  in  groups,  the  strength  of  which  should 
increase  as  the}'  are  approached  from  the  outside.  This  arrange- 
ment has  a  peculiarly  discouraging  effect  on  an  enemy.  The 
first  batteries  will  at  least  damage  him  and  cause  confusion,  thus 
weakening  his  attack  on  the  stronger;  and  when  his  discom- 
fiture finally  takes  place,  the  batteries  already  passed  will  pre- 
vent his  return  and  insure  his  total  destruction.  The  islands, 
headlands,  and  narrows  usually  found  at  the  entrances  of  bar- 
hoi's  will  generally,  to  a  greater  or  less  degree,  enable  this 
arrangement  to  he  carried  out. 

Experience  teaches  that  where  the  channel  is  unobstructed 
steam  vessels  can  run  past  shore  batteries,  however  well  the 
latter  may  be  served.  But,  on  the  other  hand,  where  obstruc- 
tions to  their  rapid  transit  exist,  they  have  not  the  endurance 
and  aggressive  power  to  effect  much  damage  to  land  defenses. 
In  the  smoke  of  battle  and  tide- way  of  the  channel  they  become 
unmanageable,  get  aground,  or  collide  with  each  other.  The 
most  effective  class  of  channel  obstructions  are  submarine  mines ; 
the  position,  planting,  and  working  of  which  arc  explained  under 
the  head  of  Submarine  Mines. 

It  is  a  well-settled  fact  that  a  hostile  fleet,  by  concentrating 
its  fire  on  an  open  work,  may  temporarily  silence  its  guns.  For 

(343) 


344  HARBOR   DEFENSES. 

this  reason  the  accumulation  of  guns  in  works  exposed  to  such 
concentration  should  be  avoided  by  distributing  them  in  bat- 
teries, each  containing  but  a  few  pieces,  due  regard  being  had  to 
their  security  from  assault  and  capture  by  any  force  that  may  be 
landed  for  that  purpose.  The  best  arrangement  is  to  place  them 
in  detached  batteries  of,  say,  two,  four,  or  six  pieces  each,  well 
secured  from  the  enemy's  fire  by  earthen  epaulments  and  trav- 
erses. This  arrangement  makes  it  difficult  for  the  enemy  to 
discover  the  exact  position  of  the  guns,  and  every  peculiarity  of 
ground  should  be  taken  advautage  of  to  increase  this  difficulty. 
Whatever  tends  to  make  batteries  difficult  to  see,  and  conse- 
quently to  hit,  is  as  much  a  protection  as  that  which  makes  them 
capable  of  resisting  a  hit  when  made.  Guns  thus  dispersed  have 
greater  freedom  of  lateral  range  of  fire,  and  do  not  interfere  so 
much  with  each  other  by  reason  of  their  smoke  as  when  concen- 
trated,— a  matter  of  no  little  importance  with  heavy  artillery, 
which  emits  such  volumes  as,  in  certain  conditions  of  the  atmos- 
phere, to  greatly  interfere  with  accuracy  of  aim. 

When  batteries  are  extended,  a  larger  area  will  be  swept  by 
their  converging  fire  than  when  the  guns  are  assembled  en 
masse.  An  additional  advantage  conferred  by  distributing  the 
guns  is,  that  while  obtaining  concentrated  fire  on  an  important 
or  decisive  point,  a  similar  fire  cannot  be  directed  on  the  guns 
in  return. 

This  arrangement  would,  furthermore,  tend  to  neutralize  the 
power  which  a  fleet  might  have  of  forming  on  a  wide  arc  of  a 
circle,  and  moving  slowly  under  steam,  so  as  to  render  the  task 
of  hitting  the  individual  ships  more  difficult,  throw  a  converg- 
ing fire  upon  the  works  on  shore. 

In  the  design  of  such  works,  it  is  of  primary  importance  that 
conjoint  action  of  the  various  parts  should  be  maintained;  and 
to  prevent  the  individual  batteries  from  being  captured  by  coup 
de  main,  small  inclosed  earth- works,  heavily  stockaded  10  resist 
escalade,  and  each  armed  with  field,  siege,  and  machine  guns, 
and  siege  mortars,  should  be  constructed  so  as  to  have  complete 
command  over  all  land  approaches. 

These  earth-works  should  contain  the  infantry  supports.  In 
this  manner  most  of  the  existing  sea-coast  forts  may  be  utilized, 
making  of  them  protecting  works  for  exterior  earthen  batteries. 

The  defenses  of  a  harbor  should,  in  every  instance,  be  capable 
of  repulsing  all  attacks  that  the  enemy  is  likely  to  make  on  them. 
The  power  and  persistenc}T  of  these  attacks  will  depend  upon 
the  importance  to  him  of  the  object  to  be  gained.  Large  and 
opulent  cities,  naval  establishments,  and  ship-yards  are  among 
the  first  prizes  sought  for.    The  aggressive  power  of   modern 


HARBOR   DEFENSES.  345 

navies  is  such  as  to  make  it  quite  impracticable  to  effectually 
guard  every  harbor  on  an  extended  coast.  It  Is,  therefore,  bet- 
ter to  entirely  abandon  those  that  are  unimportant  to  the  enemy, 
for  whatever  use  he  may  make  of  them,  than  by  feebly  guarding 
them  to  invite  his  attacks  and  thus  afford  him  the  moral  effect 
and  consolation  of  cheap  victories,  and  to  the  country  the  morti- 
fication and  disadvantage  of  defeat  and  loss  of  prestige. 

582.  Number  of  troops  required  for  harbor  defense.  The 
number  of  troops  required  for  the  manning  of  a  work  erected  for 
harbor  defense  depends  chiefly  upon  the  nature  and  amount  of 
armament  contained  therein.  Works  of  this  nature  are  armed 
principally  with  pieces  of  the  heaviest  calibre,  but,  for  reasons 
hereafter  given,  all  kinds  should  generally  find  place.  The 
amount  of  armament  depends  upon  the  extent  of  the  work  and 
the  part  it  is  to  play  in  the  scheme  of  defense. 

Three  full  detachments  are  necessary  for  each  piece.  Know- 
ing the  number  of  pieces  in  the  work  and  the  number  of  men 
required  for  the  service  of  each,  the  entire  strength  required  is 
obtained.  Three  relief  detachments  are  necessaiy,  for  the  rea- 
sons that  the  labor  of  manipulating  and  serving  heavy  artillery 
is  very  great,  and  when  a  rapid  and  continuous  fire  is  to  be  main- 
tained, strong  fatigue  parties  are  required  in  carrying  ammuni- 
tion from  the  service  magazines  to  the  pieces;  damages  done 
to  the  works  during  the  day  have  to  be  repaired  at  night,  and 
casualties  occurring,  whether  from  the  fire  of  the  enemy  or  from 
accidents,  must  be  provided  against,  so  that  at  any  moment  an 
efficient  detachment  may  be  at  every  piece. 

As  a  general  rule,  batteries  should  not  be  incumbered  by  an 
attempt  to  include  musketry  defense  within  their  limits.  The 
place  for  this  arm  is  on  the  flanks  of  the  batteries,  and  in 
strength  sufficient  to  prevent  an  enterprising  enemy  from  land- 
ing and  assaulting  the  work,  and  from  approaching  to  keep  down 
the  fire  of  the  guns  while  his  vessels  run  by  it. 

However  well  it  may  have  answered  with  the  old  style  of 
artillery  to  have  the  troops  serving  batteries  charged,  in  addi- 
tion, with  musketry  duty,  it  certainly  is  not  advisable  with  the 
artillery  of  the  present.  Steam-propelled  iron-clads,  carrying 
guns  of  enormous  power,  range,  and  accuracy,  demand  the 
undivided  attention  in  action  of  those  using  the  only  weapons 
iffective  against  such  adversaries. 

The  labor  of  handling  and  caring  for  the  kind  of  artillery, 
ammunition,  material,  and  machines  now  used,  together  with 
the  construction,  preservation,  and  repair  of  batteries,  will  re- 
quire all  the  time  and  the  whole  attention  of  the  troops  serving 


346  HARBOR   DEFENSES. 

guns  in  war.  The  care  of  infantry  arms  and  equipments,  together 
with  the  drills  and  parades  incident  thereto,  have  a  tendency  to 
draw  away  the  attention  of  officers  and  men  and  prevent  them 
from  keeping  in  an  efficient  state  of  readiness,  the  only  safe- 

fnard  that  stands  between  an  enemy  and  the  object  for  which 
e  may  desire  to  enter  a  harbor. 

When  a  work  containing  batteries  for  harbor  defense  is  inclos- 
ed, the  amount  of  musketry  necessary  for  it  is  determined  by 
allowing  two  muskets  for  each  lineal  yard  of  parapet  not  occu- 
pied by  the  batteries. 

583.  Artillery  being  the  main  feature  in  such  works,  the 
command  should  be  vested  in  an  artillery  officer.  Where  there 
are  several  forts  and  batteries  guarding  the  entrance  to  a  harbor 
or  constituting  a  line  of  works,  they  should,  for  the  purpose  of 
administration  and  command,  be  united  in  groups,  eacli  group 
being  under  an  artillery  officer  of  appropriate,  rank,  and  the 
whole  combined  and  commanded  by  the  senior  officer  of  artil- 
lery present.  B}T  this  means  thorough  cooperation  is  secured 
throughout  the  entire  system. 

584.  In  order  to  avoid  the  weakening  effect  of  divided  re- 
gponsibility,  submarine  mines,  when  employed  in  conjunction 
with  a  fort  for  the  defense  of  a  channel,  should  be  under  the 
control  of  the  commandant  of  tiie  fort,  who  should  select  from 
his  command  the  proper  number  of  officers  and  men  to  be  in- 
structed in  the  method  of  working  this  branch  of  defense. 

No  more  troops  than  are  necessary  to  carry  out  the  foregoing 
rules  should  be  crowded  into  a  work;  otherwise,  unnecessary 
casualties  from  the  fire  of  the  enemy  will  be  added,  stores  con- 
sumed, and  uuhealtliiness  engendered;  and,  besides,  in  time  of 
war,  when  troops  are  not  required  at  one  place,  their  services 
are  generally  needed  elsewhere. 

The  high  standard  of  practical  gunnery  required  of  artillery 
troops  demands  a  proportional  degree  of  intelligence  and  capacity 
for  instruction  in  the  individual  soldier.  Artillerymen  should 
be  selected  with  a  special  view  to  this,  artisans  and  mechanics 
forming  a  large  proportion.  Steam-power  and  the  application 
of  labor  and  time  saving  machinery  should,  wherever  practicable, 
be  introduced  to  assist  in  making  the  defensive  ability  of  forti- 
fied places  more  perfect. 

In  conducting  the  defense  of  a  work,  too  much  importance 
should  not  be  attached  to  the  battering  of  it  by  an  enemy ;  for 
experience  teaches  that  a  place  is  formidable,  if  resolutely  de- 
fended, long  after  it  has  lost  all  semblance  of  the  form  and  sym- 
metry possessed  by  it  when  it  came  from  the  hands  of  the  con- 
structing engineer. 


ARTILLERY    AGAINST   ARMOR.  347 

585.  Elevation  of  batteries.  Against  unarmored  vessels,, 
ricochet  firing,  owing  to  the  greater  chances  of  hitting  the 
object,  is  the  most  effective ;  and  in  order  to  secure  flattened 
ricochets^  so  that  the  shot,  in  bounding,  may  not  pass  over  the 
hostile  vessel,  batteries  should  be  placed  as  low  as  possible;  but 
since  the  introduction  of  iron-clads,  special  importance  is  giver* 
to  the  kind  of  tire  most  effective  against  them. 

Ricochet  fir'.ng  with  elongated  projectiles  is  exceedingly  un- 
certain, and  the  loss  of  power  from  ricochet  with  spherical  shot 
is  so  great  as  to  make  this  kind  of  firing  of  little  or  no  avail 
against  armored  vessels  as  now  constructed.  Direct  hits  must 
be  resorted  to,  and  these,  too,  from  rifled  guns  of  heavy  calibres. 
Direct  hits  can  be  made  as  well  from  a  moderate  elevation  as- 
from  near  the  level  of  the  water;  and,  besides,  the  chances  of 
striking  the  deck — always  the  most  vulnerable  part  of  an  iron- 
clad— are  thus  considerably  increased.  An  elevation  of  fifty 
feet  above  the  water  will  deprive  the  enemy  of  the  advantage  of 
ricochet  firing,  which,  although  not  effective  against  iron-clad 
vessels,  is  nevertheless  very  damaging  to  defensive  works  on  land. 
The  interior  of  the  work  is  obviously  more  sheltered  from  the 
missiles  of  the  enemy  when  it  is  above  his  level  than  when  low 
down  ;  his  projectiles  then  either  lodge  in  the  epaulinent  or  pass- 
over  the  work  far  to  the  rear,  with  greatly  diminished  chance  of 
hitting  the  guns,  either  in  barbette  or  in  embrasure.  (See  table,. 
par.  2 10.) 

586.  Artillery  against  armor.  Rifled  guns  of  heavy  calibres 
are,  for  reasons  hereafter  given,  the  only  kind  capable  of  inflict- 
ing much  damage  upon  iron-clad  ships.  This  damage  is  effected 
by  shot  penetrating  through  the  iron  shield  and  reaching  the 
active  enemy  within — the  men,  guns,  and  the  machinery. 

The  first  thing,  therefore,  to  be  considered  in  this  connection, 
is  the  power  of  rifled  guns  to  penetrate  armor.  A  vast  amount 
of  experimental  firing,  by  various  nations,  has  been  done  to  as- 
certain this  and  to  arrive  at  the  laws  governing  the  effect  pro- 
duced by  the  impact  of  cannon  shot  against  metal  plates.  These 
laws  have  been  formulated,  and  the  results  obtained  therefrom, 
agree,  with  remarkable  precision,  with  those  obtained  by  obser- 
vation from  actual  practice. 

These  experiments  have  been  more  exhaustive  abroad  than  irv 
the  United  States,  and  as  the  English  system  of  rifled  ordnance 
includes  all  the  calibres  of  the  United  States  system,  and  is  like- 
wise muzzle-loading,  the  diagram  on  Plate  76  is  inserted  to  show 
the  penetrating  power  of  rifles. 

The  following  table,  from  calculation,  gives  the  penetrating 
power  of  projectiles  fired  from  smooth-bore  guns  against  backed 


348 


ARTILLERY    AGAINST   ARMOR. 


armor,  for  the  velocity,  charge,  and  weight  of  projectiles  set 
opposite : 


• 

§£ 

• 

O 

• 

H 

M 

8 

•< 

*8. 

• 

§ 

5 

8 

p 

£ 

£ 

In. 

Lbs. 

Lbs. 

Ft. 

In. 

20 

1070 

200 

1400 

13 

234 

Prismatic  powder. 

15 

450 

100 

1487 

10.15 

143 

Prismatic  powder. 

10 

127 

28 

1800 

7.80 

73 

Cannon  powJer. 

The  penetration  above  given  is  for  the  velocity  at  the  muzzle; 
but  as  the  velocity  for  smooth-bores  rapidly  diminishes,  the  pen- 
etration likewise  diminishes,  and  to  such  a  degree  as  to  render 
this  class  of  guns  almost  powerless  to  perforate  modern  armor 
at  the  distances  usually  required  of  guns  on  shore. 

It  will  be  observed  from  the  foregoing  diagram  that  iron- 
clads are  classified  with  reference  to  their  armor— chiefly  as  to 
the  thickness  of  the  plating.  The  thickness  and  arrangement 
of  the  wood  backing  has  more  reference  to  the  strength  of  the 
vessel  to  resist  racking  than  to  power  of  resisting  penetration  by 
shot ;  for  the  best  oak  timber  possesses  only  about  one-sixteenth 
of  the  resisting  power  of  wrought-iron. 

The  foregoing  penetrations  are  for  impacts  normal  to  the  sur- 
face of  the  plates.  When  the  impact  is  not  normal,  the  pene- 
trating effect  is  diminished  increasingly  with  the  obliquity  of  the 
direction  of  the  shot.  Flat-headed  projectiles  encastrent  and 
penetrate  at  as  low  an  angle  as  45  degrees,  but  ogival-headed 
or  spherical  projectiles  glance  from  the  surface  when  the  angle 
reaches  about  20  degrees  from  the  normal  at  the  point  of  impact. 

The  full  penetrating  power  of  rifle  projectiles  requires  that  the 
armor  should  be  struck  perpendicularly  to  its  surface.  This  can 
never  occur  in  action  except  by  rare  accident.  The  trajectory 
of  the  shot  forms  one  angle  j  the  curvature  of  the  ship's  side 
forms  another;  the  inclination  of  the  ship's  course  forms  a  third, 
all  of  which  are  constantly  varying  by  reason  of  the  motion  of 
the  vessel. 

587.  Besides  monitors,  which  of  themselves  form  a  distinct 
class  of  iron-clads,  bearing  little  or  no  resemblance  to  any  other, 
there  arc  many  varieties  of  armored  vessels.  The  following, 
•however,  is  a  fair  type  of  the  class  that,  in  the  event  of  war, 


ARTILLERY   AGAINST   ARMOR.  349 

would  probably  prove  most  troublesome  to  our  harbor  defenses: 
Length  of  hull,  300  feet;  breadth,  56  feet ;  height  of  main  deck 
above  water,  6.5  feet.  The  tMitire  hull  is  protected  by  armor 
from  6.5  feet  below  the  water-line  to  the  main  deck,  thus  cover- 
ing* not  only  the  middle  part  of  the  ship  where  the  machinery 
and  turrets  are  placed,  but  also  the  quarters  for  officers  and  meiu 
The  thickness  of  the  armor  opposite  the  turrets  is  8  inches;  that 
on  the  remainder  of  the  midships  is  7  inches,  which  is  slightly 
reduced  towards  the  ends  of  the  vessel.  The  plates  rest  on  a 
backing  of  hard  wood  12  inches  thick,  through  which  they  are 
bolted  to  the  iron  skin,  1.5  inches  thick,  the  whole  being  sup- 
ported by  the  massive  frame-work  of  the  ship,  10  inches  deep. 

The  upper  deck,  which,  as  before  stated,  is  at  a  level  with  the 
top  of  the  armor  on  the  sides,  is  covered  with  iron  plating  4 
inches  thick  for  the  length  of  the  turret  spaces,  and  with  about 
half  the  latter  thickness  over  the  remainder.  Tin;  plating  is  laid 
on  a  deck  of  hard  wood  6  inches  thick,  the  whole  being  supported 
by  iron  beams  14  inches  deep.  The  draught  of  such  a  vessel  is 
about  26  feet. 

The  turrets,  two  in  number,  project  through  circular  openings 
in  the  upper  deck,  that  part  above  the  deck  being  covered  with 
armor  plates  10  inches  thick  about  the  ports  and  for  one-third 
of  the  circumference,  with  0  inches  for  the  remainder.  The  part 
below  the  deck  and  all  the  gearing  is  protected  b)7  the  8-inch 
armor  of  the  sides  of  the  hull.  The  height  of  the  guns  in  the 
turrets  is  10  feet  above  the  water-line. 

A  vessel  of  this  description  carries  an  armament,  usually,  of 
six  gnns,  four  of  which  are  in  the  turrets  and  are  12-inch  rifles; 
the  other  two  are  100-pounder  rifles,  and  are  carried  on  the  up- 
per deck,  fore  and  aft,  sls  chase  guns.  The  turrets  are  about 
27  feet  in  diameter. 

The  hull  of  such  a  vessel,  when  broadside-on,  presents,  exclu- 
sive of  the  turrets,  a  vertical  target,  above  water,  300  feet  long 
and  6.5  feet  high ;  any  part  of  which,  at  a  range  of  2000  yards,  if 
fairly  struck,,  is  vulnerable  to  the  racking  effect  of  shot  from  the 
15-inch  smooth-bore,  or  to  penetration  from  rifles  of  not  less 
than  10  inches  calibre ;  and  it  would  not  require  many  such  hits 
to  disable  her  or  cause  her  to  withdraw  from  action. 

When  bow-on,  the  hull  presents  a  vertical  target,  above  water,. 
66  feet  long  by  6.5  feet  high,  alike  vulnerable  to  the  same 
shots.  The  difficulty  of  striking  normally  the  curved  surface 
thus  presented  would  be  partly  compensated  for  by  the  large 
horizontal  target  presented  by  the  deck  of  the  vessel  when  in 
this  position.  This  target  would  be  360  feet  long  in  the  direc- 
tion of  the  shots,  with  an  average  width  of  about  45  feet.    The- 


350  ARTILLERY    AGAINST   ARMOR. 

angle  of  fall  due  to  shot  at  the  distance  usually  employed  against 
•iron-clads  would  give  them  a  very  considerable  striking  power, 
enabling  them,  most  probably,  either  to  penetrate  or  seriously 
rack  tho  deck.  It  is  thus  seen  that  in  whatever  position  the 
vessel  iua3r  be  with  reference  to  the  batteries  on  shore,  she  will 
present  no  inconsiderable  mark  to  Are  at. 

Rifle  projeclilesare  not  liable  to  ricochet  upon  water,  and  will, 
especially  those  that  are  pointed,  pass  through  it  to  a  distance 
•of  fifteen  to  twenty  feet  with  but  small  diminution  of  force. 
Against  this  class  of  projectiles,  the  target  presented  by  the  ves- 
sel is  increased  by  at  least  three  feet  below  the  water-line.  At 
ruuges  not  exceeding  2000  j'ards,  ricochet  from  the  15-inch  gun 
Is  formidable,  and  with  anything  like  good  practice,  shots  strik- 
ing short  would  stand  a  good  chance  of  hitting  the  vessel  upon 
the  first  rebound. 

Line-of-battle  cruisers  of  the  broadside  class  present  greater 
•dimensions,  as  a  target,  than  the  turreted  vessels  of  the  type  just 
given.  At  the  same  time,  they  carry  no  greater  thickness  of 
armor,  and  are  consequently  more  vulnerable.  The  best  protec- 
tion for  harbors  upon  the  American  side  of  the  Atlantic  against 
100-ton  guns  carried  in  vessels  protected  by  two  feet  or  more  of 
armor,  will  be  the  clumsiness  and  unseaworthiness  of  such  ves- 
sels themselves.  As  armor  increases  in  thickness,  the  belt  of  it 
that  can  be  carried  diminishes  in  width;  and  thus  what  is  pro- 
tection in  one  sense  may  be  regarded  as  weakness  in  another. 

It  is  important  with  artillerists  to  know  the  character  of  ves- 
sels opposed  to  them.  To  enable  them  to  ascertain  this,  it  is 
the  duty  of  the  proper  department  of  the  government,  in  the 
event  of  hostilities  with  a  maritime  power,  to  supply  diagrams 
showing  the  general  appearance  of  each  of  the  enemy's  iron- 
clads, or  at  least  of  each  class,  and  by  a  brief  description  to  point 
•out  the  most  vulnerable  parts.  This  would  enable  the  artillerist 
to  determine  not  only  the  proper  guns  and  projectiles  to  be  used, 
but  where  his  shots  may  be  aimed  to  the  best  advantage. 

588.  A  vessel  moving  at  the  rate  of  10  miles  an  hour  passes 
over  a  distance  of  nearly  15  feet  per  second.  The  time  of  llteht 
of  a  rifle  projectile  for  a  range  of  3000  yards  is  within  a  fraction 
of  9  seconds.  Allowing  one  second  to  elapse  from  the  time  the 
gun  is  aimed  to  the  moment  of  being  fired,  the  time  required 
for  the  projectile  to  reach  its  object  at  the  above  range  will  be 
10  seconds;  in  which  time  the  vessel  will  have  passed  over  a 
-space  of  150  feet,  or  half  the  length  of  the  average  iron-clad.  If 
she  is  at  the  above  distance,  and  moving  at  that  rate  of  speed 
directly  across  the  line  of  fire,  it  will  be  necessary,  in  order  to 
strike  her  amidship,  to  aim  directly  at  her  bow. 


VITAL   POINTS   OF  IRON-CLADS.  351 

If  she  is  moving  at  the  rate  of  15  miles  an  hour,  she  will  in 
<be  same  time  pass  over  a  distance  of  220  feet;  and  to  strike 
her  amidship,  it  will  be  necessary  to  aim  70  feet,  or  about  one- 
fourth  of  her  length,  in  front  of  her  bow. 

The  time  of  flight  of  a  projectile  from  the  15-inch  smooth-bore 
for  this  distance  is  about  one  second  greater  than  the  rifle  «4iot. 
It  will  thus  be  seen  that  the  problem  of  aiming  becomes  greatly 
-complicated  by  the  motion  of  the  vessel.  Her  distance;  the 
direction  in  which  she  is  moving,  whether  perpendicular  or  ob- 
lique to  the  line  of  Are;  hor  rate  of  speed ;  her  size,  and  the  time 
of  flight  of  the  projectile  fired,  are  all  elements  of  the  problem, 
to  be  determined  on  the  instant,  by  the  judgment  of  the  artil- 
lerist. Both  officers  and  men  should  be  thoroughly  instructed 
and  practiced  in  these  matters  for  the  particular  guns  they  are 
serving. 

Almost  every  locality  will  afford  stations  for  obtaining  cross 
bearings,  by  means  of  which,  with  telegraphic  and  other  arrange- 
ments, the  exact  position  of  a  vessel  at  any  moment  may  be 
known  at  the  piece.  The  method  of  doing  this  is  explained 
under  the  head  of  Submarine  Mines. 

"By  this  means  guns  and  mortars,  trained  upon  any  particular 
point  of  a  vessel's  course  in  a  channel,  may  be  fired  at  the  pre- 
cise moment  when  the  vessel  is  at  the  point. 

589.  Vital  points  of  iron-dads.  The  most  vital  part  of  an 
iron-clad,  or,  indeed,  of  any  ship  as  against  shot,  is  the  water- 
line,  where,  if  an  irreparable  leak  can  be  effected,  she  must 
inevitably  go  to  the  bottom.  Shot  holes  of  small  calibre  may, 
especially  in  wooden  vessels,  be  plugged ;  but  projectiles  capa- 
ble of  piercing  modern  armor  make  breaches  impossible  to  stop 
in  this  manner.  The  projectile  always  makes  a  hole  larger  than 
Its  own  diameter,  and  the  plating  at  the  exit  of  the  shot  is 
usually  bulged,  cracked,  and  carried  away  to  a  still  greater  ex- 
tent. The  wood  backing  is  torn,  splintered,  and  nicked  for  sev- 
eral feet  around,  in  such  a  manner  as  to  make  immediate  repair 
impossible.  An  iron-clad  penetrated  in  this  way,  by  even  a 
single  shot,  is  at  once  put  hors  de  combat.  Her  well-known 
irant  of  buoyancy,  although  provided,  as  most  are,  with  water- 
tight compartments,  will  cause  the  most  resolute  crew  to  desist 
the  fight  and  look  to  their  own  safety. 

The  machinery  of  sea-going  irou-clads  is  always  below  the 
water-line,  and  is  generally  protected  by  an  additional  thickness 
of  armor.  It  is  consequently  difficult  to  reach,  but  should  a 
shot  enter  there,  especially  into  a  boiler,  the  most  serious  calam- 
ity to  the  vessel  must  follow.  It  not  only  destroys  the  locomo- 
tive power  of  the  vessel,  leaving  her  without  the  means  of 


352  PHENOMENA   OF   IMPACT. 

manocuvering  or  possibility  of  escape  from  stranding,  but  if.  is 
likely  to  cause  great  destruction  of  life.  The  position  of  the 
machinery  and  boilers  of  a  steamer  is  pretty  well  indicated  by 
that  of  t  he  smoke-stack. 

When  the  vessel  is  broadside-to,  fire  should  be  directed  so  as 
to  strike  tier  at  or  just  below  the  water-line,  opposite  the  ma- 
chinery. 

Experience  teaches  that  the  most  vulnerable  part  of  a  turret 
is  its  lower  circumference,  which,  when  once  jammed,  totally 
disables  it  for  the  fight.  If,  from  weight  of  armor,  the  vessel  is 
known  to  be  invulnerable  to  the  guns  employed  against  her, 
their  lire  should  be  directed  with  a  view  to  jamming  her  turrets. 

The  ports  of  a  turret  are  generally  each  2  feet  2  inches  wide 
by  3  feet  7  inches  high,  thus  forming  no  inconsiderable  target, 
through  which  a  projectile  entering  would  destroy,  at  one  blow, 
half  of  her  armament  without  possibility  of  repair.  The  ports  1 
of  broadside  irou-clads  are  generally  about  two  inches  in  both  ' 
directions  greater  than  those  of  turrets,  and  in  number  average 
ten  for  each  side.  It  will  therefrom  be  seen  that  a  considerable 
area  of  the  ship's  side  is  thus  vulnerable. 

The  accuracy  of  fire  at  objects  on  water  is  generally  superior 
to  that  at  objects  as  they  usually  occur  on  land ;  this,  for  the 
reason  that  the  distance  of  the  object,  though  it  may  be  moving, 
is  more  readily  determined  by  its  relative  position  to  known 
objects,  the  position  of  which  are  well  understood  beforehand. 
The  effect  of  the  shot  can  be  more  easily  observed  on  water  than 
on  land.  The  size  of  the  object,  if  a  vessel,  is  large,  and  its  ap- 
pearance generally  well  defined. 

590.  Phenomena  of  impact.  When  a  heavy  beam  of  wrought- 
irou — one,  say,  twelve  or  fourteen  inches  square — is  struck  by  a 
heavy  shot  at  high  velocit)*,  the  beam  snaps  short  off,  as  though 
it  were  cast-iron.  The  same  shot,  striking  a  wrought-iron  plate 
backed  in  the  usual  manner  of  armor,  penetrates  or  perforates 
it  in  a  manner  similar  to  the  action  of  a  hand-punch  on  a  sheet 
of  iron  laid  on  a  block  of  wood.  The  effect  is  entirely  local ;  the 
hole  is  made  without  bending  or  twisting  the  plate  in  one  case, 
or  the  sheet  in  the  other.  The  same  projectile,  propelled  with 
a  low  velocity,  will  bend  the  beam  and  produce  the  ordinary 
fracture  of  wrought-iron,  and  in  case  of  the  plate,  the  latter  will 
be  distorted,  strained,  and  loosened  from  its  fastenings. 

A  simple  way  of  explaining  these  phenomena  is  as  follows: 
In  the  case  of  the  high  velocity  the  effect  is  wholl}'  locals  because 
the  surrounding  material  has  not  time  to  propagate  the  vibration 
of  impact  throughout  the  mass.  In  other  words,  the  cohesion 
of  the  material  is  not  sufficient,  in  the  time  allowed,  to  overcome 


RACKING — PUNCHING.  353 

the  inertia  of  the  surrounding  mass.  The  distribution  of  the 
effect  in  the  other  case  is  due  to  the  low  velocity,  wherein  a 
certain  length  of  time  is  consumed  in  accomplishing  the  blow. 
During  this  interval,  all  surrounding  particles  of  iron  have  rime 
to  sustain  the  point  struck ;  the  force  of  the  blow  is  thus  spread 
over  a  large  surface  and  the  cohesion  of  the  particles  is  undis- 
turbed, since  each  particle  Is  enabled  to  contribute  the  force  of 
its  attraction  towards  uniting  the  whole.  These  two  distinct 
effects  are  called,  respectively,  punching  and  racking. 

The  work  done  by  a  shot  is  represented  by  its  weight  multi- 
plied by  the  square  of  its  velocity  at  the  moment  of  impact; 
from  which  it  will  he  seen  that  a  small  projectile  moving  with 
great  velocity  is  capable  of  doing  the  same  amount  of  work  as  a 
large  projectile  with  low  velocity.  The  character  of  the  work 
is,  however,  as  above  explained,  entirely  different.  In  case  of 
a  given  projectile,  whatever  power  is  employed  in  racking  the 
side  of  the  vessel  does  nothing  towards  penetration,  and  vice 
versa. 

Racking.  The  theory  in  favor  of  the  racking  system  is,  that 
heavy  projectiles  may  be  fired  with  low  velocities  without  strain- 
ing the  gun;  that  blows  given  in  this  way  waste  no  power  in 
punching  mere  holes,  but  that  the  entire  work  will  be  expended 
in  straining,  loosening,  and  dislocating  the  armor  and  breaking 
its  fastenings,  tearing  it  off  and  exposing  unprotected  spots  eas- 
ily vulnerable  to  shells,  at  the  same  time  racking  and  breaking 
the  ribs  and  sides  of  the  vessel  to  such  extent  as  to  render  her 
unseaworthy.  For  producing  these  effects  the  15-inch  gun, 
throwing  solid  cast-iron  balls,  is  quite  as  formidable  as  the  pow- 
erful rifle  expending  costly  bolts ;  but  the  accuracy  of  fire  f  rom 
the  rifle  is  so  greatly  superior  to  that  from  the  smooth-bore,  as  to 
leave  a  large  margin  in  its  favor.  Spherical  shot,  and  slow  shot 
of  any  form,  will  do  very  little  execution  under  water.  The 
•oncussion  from  racking  blows,  although  it  may  not  seriously 
injure  the  vessel,  stuns  and  temporarily  paralyzes  many  of  the 
3rew,  and,  spreading  terror  to  all,  greatly  interferes  with  the 
3fficient  working  of  the  ship  and  of  her  armament. 

Punching.  The  theory  in  favor  of  punching  is,  that  the  vital 
parts  of  the  vessel  and  the  active  enemy  within — the  men,  guns, 
and  machinery — are  reached  at  once.  A  projectile  piercing  the 
armor  of  a  vessel  carries  with  it  portions  of  the  broken  plate, 
which,  together  with  bolts,  nuts,  and  fragments  of  wood  from 
the  backing,  form  a  species  of  langrage,  the  effect  of  which  is  not 
less  to  be  feared  on  a  crowded  deck,  or  in  a  turret,  than  the 
explosion  of  the  most  formidable  shell.  But  to  produce  this 
result  the  projectile  must  penetrate  entirely  through.  A  pro- 
jectile moving  with  a  punching  velocity  has  only  local  effect, 

23 


354  ARMOR-PUNCHING   PROJECTILES. 

penetrating  without  racking  the  armor.  If  it  goes  but  partly 
through,  it  does  no  damage  either  to  the  ship  or  to  the  enemy 
within.  Therefore,  whether  from  the  greatness  of  range,  the 
thickness  of  the  armor,  or  want  of  power  in  the  gun,  entire  per- 
foration cannot  be  effected,  it  is  only  a  waste  of  ammunition  to 
use  it  in  simply  indenting  armor. 

Although  a  spherical  projectile  may  have,  upon  starting,  great- 
er velocity  than  a  rifle  projectile  of  equal  calibre,  and  conse- 
quently may  have  greater  punching  power  stored  up  in  it  at  this 
part  of  its  flight,  nevertheless,  owing  to  its  greater  cross-sectional 
area  in  proportion  to  its  weight,  it  will  lose  its  velocity  more 
rapidly,  and  the  rifle  projectile  will  soon  overtake  it  in  its  flight 
and  go  far  beyond  it  in  range. 

At  the  distances  that  iron-clads  usually  engage  land  batteries, 
smooth-bore  projectiles  would  possess  no  punching  power ; 
therefore  for  this  kind  of  work  rifles  are  the  only  suitable  arma- 
ment for  such  batteries.  They  should  be  powerful  enough  to 
do  the  work  effectually. 

When  heavy  enough  for  this,  all  additional  weight  is  rather  a 
detriment  than  an  advantage,  from  the  fact  that  light  guns  are 
less  cumbersome,  can  be  fired  more  rapidly,  are  more  easily  re- 
placed when  disabled,  and  less  costly  in  ammunition.  They 
likewise  stand  greater  relative  charges  and  yield  higher  veloci- 
ties with  safety. 

The  8- inch  rifle,  carrying  a  projectile  185  pounds  in  weight, 
fired  with  a  charge  of  35  pounds  hexagonal  powder,  is  the  mini- 
mum calibre  that  can  be  successfully  used  against  the  present 
style  of  sea-going  iron-clads. 

591.  Armor-punching  projectiles.  Spherical  solid  shot  of 
cast-iron,  as  usually  furnished,  almost  invariably  break  into 
many  fragments  upon  strikiug  armor  plates.  When  made  with 
particular  care  as  to  quality  of  metal  and  mode  of  casting,  they 
will  penetrate,  provided  the  velocity  is  not  too  much  reduced  by 
range,  but  in  doing  so  have  a  tendency  to  break  after  entering 
the  armor, — a  circumstance,  however,  rather  in  their  favor  when 
they  pass  entirely  through,  as  they  then  scatter  their  fragments 
in  the  interior  of  the  ship.  Spherical  shells  of  cast-iron  have 
not  strength  to  penetrate  unimpaired  armor,  and  are  useful 
against  iron-clads  only  when  they  chance  to  strike  a  weakened 
part  of  the  vessel.  They  nevertheless  have  other  uses;  their 
large  fragments  may  enter  the  ports  and  do  the  work  of  solid 
projectiles  within;  an  unremitting  fire  with  them  will  blind  the 
enemy  by  their  explosion  and  bewilder  and  distract  him  to  such 
an  extent  as  to  render  his  fire  scattering  and  uncertain.  The 
best  materia]  for  rifle  projectiles  for  punching  purposes  is  Bes- 
semer steel,  but  as  it  is  too  expensive  for  ordinary  service,  chill- 


STRENGTH  AND   COMPOSITION   OF  BATTERIES.      355 

ed  cast-iron  is  used.  The  form  of  head  best  suited  for  the  per- 
foration of  plates,  whether  direct  or  oblique,  is  the  ogival  or 
pointed  arch.  The  flat-headed  projectile  possesses  some  advan- 
tage over  the  ogival  in  taking  hold  of  the  plate  at  a  greater  angle 
of  obliquity,  but  this  advantage  is  counterbalanced  by  less  range 
and  accuracy  of  flight.  The  effect  of  striking  a  plate  obliquely 
is  diminished,  as  regards  power  of  perforation,  in  the  proportion 
of  the  sine  of  the  angle  of  incidence  to  unity.  Elongated  shells 
of  good  metal  and  thickness  have  a  power  of  penetration  but 
little  inferior  to  corresponding  solid  projectiles. 

The  heat  generated  by  impact  against  armor  will  usually  ignite 
the  charge,  and  the  bursting  takes  place  about  the  time  the  shell 
reaches  the  backing  of  the  armor.  The  head  and  walls  of  the 
shell  require  to  have  sufficient  thickness  to  resist  crushing  by 
the  force  of  the  blow. 

592.  Strength  and  composition  of  batteries.  In  determining 
the  armament  necessary  to  protect  a  harbor  from  an  enemy's 
fleet,  it  may  be  laid  down  that  no  iron-clad  carrying  a  certain 
number  of  guns  can  successfully  attack  a  battery  on  shore  prop- 
erly situated  and  armed  with  a  like  number  of  guns  of  calibre 
equal  to  the  task  of  racking  or  punching  her  armor.  But  as 
vessels  are  capable  of  moving,  and  can  pass  by  and  out  of  range 
of  batteries  on  shore  in  a  given  period  of  time,  the  chance  of 
their  being  crippled  or  disabled  will  be  in  direct  proportion  to 
the  number  of  guns  employed  against  them ;  hence  this  number 
should  be  as  large  as  circumstances  will  admit. 

Assuming  4000  yards  as  the  maximum  effective  range  against 
a  vessel,  8000  yards  would  be  the  distance  she  would  have  to 
pass  over  in  running  by  and  beyond  the  range  of  a  battery.  At 
a  rate  of  speed  of  15  miles  an  hour,  she  would  accomplish  this 
in  a  little  less  than  18  minutes;  at  10  miles,  in  a  little  over  27 
minutes.  Supposing  everything  in  the  battery  to  be  in  the  most 
complete  order  and  state  of  readiness,  not  more  than  three  shots 
from  the  15-inch  smooth-bore  or  12-inch  rifle  could  be  fired  in 
the  first  interval,  and  not  over  five  in  the  second.  Twice  this 
number  might,  however,  be  fired  from  pieces  of  less  calibre. 
The  movement  of  the  vessel  would  greatly  diminish  the  chances 
of  hitting  her,  and,  besides,  it  is  by  no  means  every  hit  that 
seriously  injures  an  iron-clad.  This  suggests  that  the  number 
of  guns  should  be  as  great  as  possible. 

The  pieces  in  each  battery  should,  as  a  rule,  be  of  the  same 
calibre  and  kind ;  but  the  batteries  themselves  should  be  mixed 
as  to  armament.  The  smaller  calibres  are  more  easily  worked, 
and  are  capable  of  rapid  fire.  This  would  be  effective  against 
wooden  vessels  assisting  in  the  passage  or  attack.  When  a  ves- 
sel is  stopped  by  an  obstacle  in  the  channel,  fire  should  be  con- 


»356  MORTARS   AGAINST  IRON-CLADS. 

centrated  upon  it,  for  the  reason  that  in  this  position  it  is  most 
liable  to  be  disabled,  and,  being  disabled,  will  embarrass  the 
remainder  of  the  fleet  and  tend  to  frustrate  the  plans  of  the 
enemy. 

To  guard  against  ships  taking  advantage  of  night  to  run  by  a 
work,  the  guns  should  be  trained  upon  the  channel-way,  prefer- 
ably that  portion  exposed  to  enfilade  fire,  and  the  traverse  circle 
so  marked  that  the  pieces  can  be  readily  aimed  after  each  dis- 
charge. The  marking  should  be  done  in  such  a  manner  as  to  be 
readily  used  in  the  dark.  This  may  be  effected  by  placing  a 
straight-edge  against  one  side  of  the  fork  of  a  traverse-wheel, 
and  making  a  nick  in  the  traverse  circle  with  a  cold-chisel ;  the 
straight-edge  placed  in  the  same  position  will  show  when  the 
gun  has  the  same  direction.  The  chances  of  hitting  a  vessel  be- 
ing greatly  diminished  by  darkness,  it  is  most  advantageous 
under  such  circumstances  to  use  shells.  This  kind  of  firing  car- 
ries with  it  at  night  a  peculiar  moral  effect  which  may  greatly 
interfere  with  the  navigation  of  the  vessel.  When  the  vessel 
arrives  within  easy  range,  round  shot,  fired  in  ricochet,  will  be 
found  effective. 

593.  Mortars  against  iron-clads.  Vertical  fire  is  effective 
when  it  is  desirable  to  prevent  an  enemy  from  occupying  certain 
anchorage.  The  deck  of  a  ship  is  as  completely  vulnerable  to 
falling  shells  as  the  bottom  is  to  submarine  mines  and  torpedoes. 
Judiciously-placed  batteries,  if  armed  with  a  sufficient  number 
of  mortars  throwing  showers  of  shells,  would  make  it  perilous 
for  an  enemy  to  remain  within  their  reach.  But  mortar  tiring 
from  smooth-bore  mortars  is  at  best  somewhat  wild,  and  depends 
on  quantity  for  its  effectiveness.  It  is,  however,  safe  to  say  that 
no  fleet  nor  vessel  can  remain  under  well-directed  fire  from 
heavy  mortars.  A  battery  of  one  hundred  heavy  mortars  will 
keep  at  bay  all  the  iron-clads  that  can  manoeuvre  or  anchor 
within  their  range.  The  moral  effect  of  mortar  firing  is  appall- 
ing, and  increases  vastly  with  the  numbers  of  mortal's  used. 

The  armor  that  a  vessel  is  capable  of  carrying  on  her  deck,  in 
addition  to  that  upon  other  parts,  is  not  sufficient  to  resist  the 
crushing  power  of  a  13-inch  shell  with  maximum  velocity— 419 
feet  per  second.  The  10-inch  mortar  is  serviceable  only  against 
unarmored  decks,  or  those  very  slightly  protected.  In  firing  at 
iron-clads  the  shells  should  not  burst  before  striking ;  in  fact,  it 
is  best  to  fill  the  shells  with  sand  instead  of  powder.  Solid  shot 
would  be  preferable  to  either. 

Mortars  mounted  on  the  centre-pintle  traversing  chassis,  and 
provided  with  the  pointing  apparatus  described  on  page  64,  are 
capable  of  following  the  course  of  a  moving  vessel  with  the  same 
facility  as  a  gun. 


gart  gmnih. 


FIELD  INTRBNCHMBNT8. 

594.  In  active  service  it  is  frequently  necessary  for  artillery 
troops  to  construct  works  for  the  emplacement  of  their  weapons. 
Such  troops  should  therefore  be  instructed  in  the  art  of  select- 
ing sites,  laying  out  and  erecting  batteries,  magazines,  bomb- 
proofs,  traverses,  and  other  works  immediately  connected  with 
the  efficient  service  of  their  special  arm. 

When  positions  are  to  be  taken  up  and  lines  of  intrenchments 
or  detached  works  are  to  be  constructed,  it  is  the  duty  of  artil- 
lery officers,  in  cooperation  with  those  of  engineers,  to  select 
positions  for  batteries  and  determine  the  kind  and  amount  of 
armament  therefor.  It  is  therefore  necessary  that  they  should 
be  thoroughly  conversant  with  the  principles  of  military  engi- 
neering, especially  those  of  field  intrenchments. 

The  object  of  every  fortification  is  to  shelter  the  troops  occu- 
pying it  from  the  view  and  fire  of  an  assailant,  and  at  the  same 
time  to  afford  them  a  commanding  view  and  sweeping  fire  over 
their  enemy. 

Earth  is  the  principal  material  employed  on  land  for  resisting 
the  fire  of  artillery.  Wood,  iron,  and  masonry  are  used  in  con- 
junction with  it,  principally  for  sustaining  purposes. 

As  a  material  for  fortifications,  earth  possesses  advantages  over 
all  other,  in  being  found  ready  at  hand  in  almost  all  localities 
where  wanted  for  such  purposes,  in  being  easily  handled,  and  in 
possessing  unrivaled  properties  of  resistance  as  a  covering  mass 
against  projectiles. 

595.  Penetration.  At  moderate  distances  there  is  but  little 
difference  between  the  penetrating  power  of  rifle  and  smooth- 
bore guns  throwing  projectiles  of  equal  weight ;  but  as  the  rifle 
has  great  superiority  in  range,  its  penetrating  power  at  long 
distances  greatly  exceeds  that  of  the  smooth-bore. 

The  following  tables,  the  result  of  actual  flriug,  show  the 
maximum  penetration,  for  various  calibres,  in  different  earths, 
and  convey  a  good  idea  of  the  enormous  power  of  modern  artil- 
ery. 

Since  the  dates  of  these  firings,  great  improvement  has  been 
nade  in  the  character  of  powder  used  with  the  heavier  classes  of 
guns,  whereby  much  larger  charges  are  used  and  greater  range 
and  penetrating  energy  gained. 

(357) 


358 


FIELD  INTRENCHMENTS. 


In  a  bluff  bank  of  natural  soil  of  clay  and  sand. 


Kind  of  Piece. 


100-pdr.  rifle  (Par't.) 
Solid  shot....~~~...... 


Siege  gun  (rifle.) 


Brooks  rifle.. 

0X&GXJ.  •••••••  '•• 


MMWt>»tl 


Parrott  rifle. 
Solid  shot .... 


Calibre. 


Inches. 
6.4 


4.5 

7 


12 


WEIGHT 
OP  PRO- 
JECTILE. 


Pounds. 


98.5 


27 


597 


Charge. 

OF 
POWDER. 


Pounds. 


10 


3.5 


85 


I 


Yds. 
1800 


1800 

2700 

200 


PENE- 
TRATION. 


Feet. 
15*" 


11 


16 
31.5 


H 
H 

< 
P 


1863 


1863 


1864 


In  a  well-settled  parapet  of  clay  and  sand. 


Kind  of  Pises. 


HXVpdr.  rifle  (Par't.) 

Solid  shot 

Shell .... 


80-pdr.  rifle  (Par't.) 

Solid  shot ~ 

Shell 


20-pdr.  rifle  (Par't.) 
Solid  shot .....~........ 

Shells 


i 


10-pdr.  rifle  (Par't.) 
Shell 


Calibre. 


Inches. 
6.4 


4.2 


3.67 


Weight  of 
Projec- 
tile. 

Charge 

of 
Powder. 

• 

O 

1 

Pene- 
tration; 

Pounds. 

Pounds. 

Yds. 

Feet. 

98.5 
92 

•••••• 

10 

383 

18 
16 

•••••• 

30.5 
27.5 

3.5 

383 

•••• > « 

12 
12 

16 
14.25 

2 

383 

10 
9 

10.6 

1 

383 

10 

w 

P 


1863 
1863 


1863 
1863 


1863 
1863 


1863 


FIELD   IXTRENCH.UENTS. 


359 


In  a  parapet  of  pure  quartz  sand,  well  rammed. 


Kind  of  Piece. 

Oalibbe. 

"Weight  op 
Projec- 
tile. 

Charoe 

OF 

Powder. 

S 

PENE- 
TRATXOIT. 

• 

M 

H 

A 

1867 
1866 
1866 

•••■■• 

1867 

Solid  shot.********....*. 

Inches. 
12 

10 

8 

15 

Pounds. 

630 
485 

208 
266 

...... 

141 

451 

Pounds. 
TO 

——* 

80 
25 

14.5 
100 

Yds. 
175 

400 

480 
200 

Feet. 

20 
18 

15.1 
16.1 

14.1 
11 

22 

Solid  shot mm...... 

U.  S.  smooth-bore... 

In  a  parapet  of  clay,  well  rammed. 


Kind  of  Piece. 

Calibre. 

Weight  of 
Projec- 
tile. 

Charge 

of 
Powder. 

• 

H 

Pene- 
tration. 

• 

1 

1867 
1867 

XJ.  5.  rifle.  ...*•••••.....* 
TJ.  S.  smooth-bore... 

Inches. 
12 

15 

Pounds. 

• ••••* 

625 
485 

450 
830 

Pounds. 
70 

•••••• 

••■••• 

100 
55 

Yds. 
175 

175 

Feet. 

36 
84 

88 
24 

In  a  parapet  of  clay  and  sand,  well  rammed. 


Kind  of  Piece. 

Calibre. 

Weight  of 
Projec- 
tile. 

Charge 

of 
Powder. 

H 

Pene- 
tration. 

• 

1 

1867 

Inches. 
12 

8 
15 

Ponnds. 

625 
150 

450 

Pounds. 

70 
18 

••••• • 

100 

Yds. 
175 

24 
175 

Feet. 

34 
18.5 

22 

200-pdr.  rifle  (Par't.) 
U.  S.  smooth-bore... 

360 


FIELD   INTRENCHMENTS. 


English  guns. 

Kind  op  Piece. 

Parapet  of  clay  and 

sand,  well  rammed. 

Range,  1060  yds. 

Natural  bank  of  clay 

and  sand.    Range, 

1060  yards. 

1 

Shot. 

Shell. 

Shot. 

Shell. 

Ft.   In. 

Ft.   In. 

Ft.   In. 

Ft.   In. 

In. 

100-pdr.  Armstrong. 
70-pdr.  Armstrong... 
40-pdr.  Armstrong... 
20-pdr.  Armstrong... 
12-pdr.  Armstrong... 

21       3 
14       4 
14     11 
10     10 

16     8 

11     8 

11      1 

4      0 

10     3 
5     9 
7     2 
4     7 

•••          ••• 

10     5 

•••    ••» 
5     9 
5     5 
2     7 

7.09 
6.48 
4.84 
3.84 
3.07 

10-inch  smooth-bore 
8-inch  smooth-bore.. 
68-pdr.  smooth-bore. 
32-pdr.  smootb-bore. 

•  ••            ••• 

•  ••            ••• 

19      11 
33       0 

11     5 

11     6 

14    10 

9      5 

•••          ••• 

•••          •  ■• 

9      3 
3     9 

6  7 
4    10 

7  6 

2     8 

9.84 
7.85 
7.85 
6.17 

The  foregoing  tables,  both  American  and  English,  are  abstracts 
from  many  shots,  from  which  it  will  be  seen  that,  even  with 
smooth-bore?,  penetration  is  quite  variable.  It  will  be  observed 
also  that  there  is  a  great  difference  in  the  resisting  properties 
of  the  various  earths,  pure  clay  possessing  the  least  and  sand 
the  greatest.  It  may  here  be  stated  that  the  resistance  of  dry 
sand  is  slightly  greater  than  that  of  wet,  and  dry  clay  very  much 
greater  than  moist. 

Spherical  projectiles  are  much  more  uniform  in  penetration 
than  elongated.  With  the  latter,  it  depends  in  a  great  degree 
upon  the  direction  preserved  by  the  axis  of  the  shot;  wiien  this 
remains  so  that  the  projectile  strikes  directly,  point  foremost, 
the  penetration  is  greatest,  but  a  very  slight  object  will  fre- 
quently cause  it  to  turn  while  penetrating,  and  thereby  diminish 
the  penetration,  sometimes  nearly  one-half.  When  the  medium 
is  homogeneous,  the  tendency  of  the  projectile  after  entering  it 
is  to  turn  to  the  right  or  in  the  direction  of  the  twist,  to  curve 
upwards,  and  to  lodge  with  the  base  towards  the  left.  After  the 
primary  impact  it  does  not,  as  a  general  rule,  continue  to  pene- 
trate point  foremost;  this,  in  earth,  causes  it  to  have  a  plough- 
ing effect  not  possessed  in  so  great  a  degree  by  spherical  pro- 
jectiles. Percussion  shells  attain  fully  three-fourths  of  their 
entire  penetration  before  bursting.  Time-fuses,  unless  protected 
by  water-caps,  are  liable  to  be  extinguished  upon  entering  earth. 
Percussion  shells  should,  therefore,  be  preferably  employed 
against  magazines,  where,  by  entering  and  bursting,  they  will 
cause  an  explosion. 


FIELD   INTRENCHMENTS.  861 

As  a  general  rule,  penetration,  both  for  smooth-bores  and  for 
rifles,  increases  with  the  calibre  of  the  piece  and  the  weight  of 
the  projectile. 

The  craters  formed  by  the  explosion  of  shells  are  much  greater 
in  clayey  earths  than  in  sand.  In  fact,  but  little  impression  is 
made  on  the  latter,  as  the  sand,  when  thrown  up  by  the  explo- 
sion, settles  back  almost  in  its  former  position. 

The  ratio  of  increase  of  craters  is  generally  in  excess  of  the 
increase  of  weight  of  the  shells  or  of  the  bursting  charges.  A 
rifle  projectile  tears  a  long  furrow  previous  to  explosion,  scatter- 
ing the  earth  to  either  side,  and  on  bursting  uplifts  and  displaces 
a  large  mass  of  earth,  whereas  spherical  shells  merely  bury  them- 
selves and  raise  up  a  comparatively  small  quantity  of  earth,  the 
larger  portion  of  which  falls  back  into  the  crater.  Hence  the 
rifle  is  superior  to  the  smooth-bore  for  demolishing  earth- works. 

When  a  projectile,  spherical  or  elongated,  strikes  a  slope,  as, 
for  instance,  the  superior  slope  of  a  parapet,  and  takes  a  direc- 
tion approximately  parallel  to  it,  it  makes  an  open  furrow,  pro- 
vided the  depth  below  the  surface  is  not  greater  than  about  four 
times  the  diameter  of  the  shot.  This  indicates,  what  experience 
has  proved,  namely,  that  the  best  method  of  breaching  earth- 
works is  to  direct  a  concentrated  fire  of  shells  from  rifle  guns, 
with  full  service  charges,  upon  the  parapet  in  such  manner  as 
to  cut  it  gradually  down  from  the  superior  slope  to  the  base. 
The  great  accuracy  of  rifle  guns  enables  this  to  be  done.  The 
shells,  after  having  performed  their  work  in  the  parapet,  send 
their  fragments  be}rond  and  carry  destruction  to  the  interior  of 
the  work.  A  few  heavy  pieces  are  far  more  effective  in  accom- 
plishing this  object  than  a  greater  number  of  smaller  calibres, 
although  the  aggregate  of  metal  thrown  may  be  in  favor  of  the 
smaller  guns. 

In  this  connection  it  may  be  mentioned  that  a  vigilant  and 
active  garrison,  by  taking  advantage  of  the  darkness  of  night, 
will  repair  an  earth-work  faster  than  the  most  powerful  artillery 
can  reduce  it.  Nevertheless  it  is  possible  to  maintain  such  a  fire 
during  the  day  as  will  cut  clown  the  parapet  and  uncover  the 
interior  of  the  work  sufficiently  to  allow  of  the  destruction  of 
magazines,  bomb-proofs,  and  other  arrangements  for  defense 
not  so  readily  repaired,  and  the  destruction  of  which  may  event- 
uate in  the  loss  of  the  work. 

For  the  purpose  of  retarding  as  much  as  possible  repairs 
during  the  night,  the  assailants  should  maintain  upon  that  part 
of  the  work  a  constant  shower  of  shells  from  mortars. 

596.  To  provide  a  safe  margin  against  the  cutting-down 
effect  of  the  enemy's  fire  and  to  preserve  the  interior  revet- 


362  FIELD   INTRENCHMENTS. 

meats  of  a  work  from  destruction  or  injury  by  the  impact  of 
shot  or  explosion  of  shells,  the  epaulment  must  be  made  consid- 
erably thicker  than  the  actual  penetration  of  the  projectiles  used 
against  it.  Formerly  this  additional  thickness  was  put  down  at 
one-half,  but  this  is  manifestly  greater  than  is  necessary  for  the 
artillery  now  in  use. 

An  addition  of  one-third  of  the  maximum  penetration  is  ample. 
Assuming  this  as  the  rule,  parapets  constructed  of  ordinary 
earth — i.  e.,  clay  and  sand  mixed  and  well  rammed — should  have 
the  following  thicknesses :  Range  1500  yards — To  resist  12-inch 
rifle,  45  feet ;  10-inch  rifle,  35  feet ;  8-inch  rifle,  25  feet ;  6.4- 
inch  rifle,  22  feet;  15-inch  smooth-bore,  30  feet.  Range  1000 
yards — To  resist  4.5-inch  rifle,  16  feet;  3.67-inch  rifle,  15  feet; 
3-inch  rifle,  14  feet. 

For  parapets  constructed  of  sand:  Range  1500  yards  —  To 
resist  12-inch  rifle,  30  feet;  10-inch  rifle,  25  feet;  8-inch  rifle, 
20  feet ;  6.4-inch  rifle,  18  feet ;  15-inch  smooth-bore,  25  feet. 

Common  earth,  (mixture  of  clay  and  sand,)  loosely  thrown  up, 
offers  much  less  resistance  to  penetration  than  when  settled ; 
with  sand  the  difference  is  not  so  great. 

Interior  revetments  of  ordinary  thickness,  whether  of  ma- 
sonry, sods,  or  gabions,  give  but  little  additional  resisting  power 
to  a  parapet,  and  should  not  therefore  be  taken  into  account 
when  estimating  its  thickness. 

From  experiments  made  for  the  purpose  of  determining  the 
best  form  and  dimensions  for  masonry  breast-height  walls,  it  was 
found  that  15-inch  smooth-bore  projectiles  flred  at  a  butt  200 
yards  distant,  after  passing  through  20  feet  of  well-rammed  sand, 
overturned  a  wall  of  best-laid  granite  masonry  3  feet  thick  and  5 
feet  high.  The  penetration  was  but  little  inferior  to  that  of  sim- 
ilar shot  fired  into  unsupported  sand.  The  projectiles,  although 
not  coming  in  actual  contact  with  the  wall,  (in  most  instances 
lodging  several  feet  from  it,)  transmitted  the  force  of  their  im- 
pact through  the  intervening  sand,  each  one  forcing  the  wall 
more  and  more  from  the  perpendicular,  until  at  the  sixth  it  fell 
bodily. 

With  a  parapet  of  12  feet  of  well-rammed  sand  against  a  breast- 
height  wall  of  concrete  6.5  feet  high,  5  feet  thick  at  top  and  7  feet 
2  inches  at  bottom,  projectiles  from  the  same  gun,  with  a  range 
of  430  3'ards,  demolished  the  wall ;  not,  however,  as  in  the  pre- 
ceding case,  by  overturning  it,  but  by  cracking  and  crumbling 
it.  In  this  case  the  shot  penetrated  to  the  concrete  and  destroyed 
it  by  direct  impact. 

With  a  parapet  of  9  feet  of  sand  against  a  concrete  breast- 
height  wall  8  feet  thick  at  top  and  10  feet  2  inches  at  bottom, 


PENETRATION   OF   RIFLE-MUSKET.  86$ 

projectiles  from  a  12-inch  rifle,  at  a  range  of  430  yards,  demol- 
ished the  wall  in  a  manner  similar  to  the  foregoing  case. 

With  a  parapet  of  7  feet  of  sand  against  a  concrete  breast- 
height  wall  10  feet  thick  at  top  and  12  feet  2  inches  at  bottom,, 
projectiles  from  a  16-inch  smooth-bore  gun  (the  range  being  as- 
above)  cracked  the  wall,  but  did  little  or  no  other  damage  to  it. 

In  these  experiments  it  was  demonstrated  that  when  the  wall 
is  stont  enough  to  resist  the  projectiles,  the  latter  invariably 
glance  upwards  and,  passing  out  through  the  interior  crest,  fail 
within  the  parapet  at  distances  varying  from  a  few  yards  up  to» 
a  thousand  or  more.  After  thus  glancing  they  are  still  capable- 
of  doing  considerable  damage  to  the  interior  of  a  work. 

These  facts  go  to  prove  that  however  massive  a  sustaining  wall 
may  be,  there  should  be  sufficient  earth  in  front  of  it  to  arrest 
the  projectiles  the  same  as  though  there  were  no  wall  at  all. 
Hence  it  will  be  economy  of  labor,  material,  and  space  to  have- 
revetments  as  slight  as  is  consistent  with  the  object  of  holding 
up  the  earth  of  the  parapet. 

597.  Penetration  of  shells  from  mortars.  In  sand  and  in 
compact  clayey  earths,  such  as  would  generally  be  employed  for 
the  coverings  of  magazines  and  bomb-proofs,  the  penetration  of 
mortar  shells  falling  with  maximum  velocities  is  about  three 
times  their  diameters;  but  in  order  that  the  lining  of  the  maga- 
zine or  bomb-proof  may  not  be  injured  by  their  impact,  double 
this  thickness  should  be  given. 

Shells  tired  from  guns  at  high  elevation  possess  many  of  the 
properties  of  mortar  shells;  but  as  the  velocity  is  much  greater* 
the  penetration  also  is  greater,  and  their  effect  upon  striking  is 
more  destructive;  consequently,  additional  thickness  of  earth  is 
required  for  magazines  and  bomb-proofs  exposed  to  this  kind  of 
fire. 

In  clayey  earth  the  mouth  of  the  crater  formed  by  the  explo- 
sion of  a  mortar  shell  is  about  four  times  the  diameter  of  the 
shell;  in  sand  it  is  considerably  less. 

The  maximum  velocity  of  a  descending  mortar  shell  is  419  feet 
per  second,  or  about  one-third  that  of  the  striking  velocity  of 
projectiles  fired  from  guns  at  ordinary  distances.  This  accounts 
for  the  comparatively  small  penetration  of  the  former. 

Shells  of  any  kind  striking  on  marshy  ground  bury  themselves 
so  deeply  as  to  produce  but  little  effect  by  explosion. 

598.  Penetration  of  rifle- musket.  Recorded  experiments 
give  somewhat  conflicting  results  on  this  head,  but,  to  be  on  the 
safe  side,  the  following  thicknesses  appear  to  be  needful  to  give- 
security  against  infantry  fire :  Clay,  loosely  thrown  up,  4  feet  £ 
sandy  or  gravelly  earth,  loosely  thrown  up,  3  feet;  sand-bag* 


364  INTRENCHED   CAMPS. 

filled,  1.25  feet;  gabions  (wicker),  filled  with  earth,  1.75  to  2 
feet;  pine  (soft),  16  to  18  inches;  oak  and  elm  (green),  6  inches; 
ash  (green),  4.5  inches;  sap-roller  and  fascines  (green),  12  to  15 
inches;  brick-work,  4.5  inches;  boiler-plate,  ^  inch. 

The  above  are  for  distances  not  exceeding  100  yards ;  beyond 
that,  penetration  diminishes  rapidly  with  the  range.  At  a  dis- 
tance of  twenty  yards  a  rope  mantlet  4  inches  thick  is  proof 
against  a  rifle-musket  shot.  As  weight  is  a  consideration  in 
mantlets,  they  need  not  be  given  a  greater  thickness  than  this 
to  insure  all  necessary  security  from  such  fire. 

599.  Field  intrenchments  may  be  classified  as  follows  :  1. 
Intrenched  camps;  2.  Intrenched  lines  of  battle;  3.  Detached 
works;  4.  Lines  of  works;  5.  Works  auxiliary  to  permanent 
fortifications ;  6.  Works  for  siege  operations. 

600.  So  far  as  artillery  is  concerned,  the  first  object  to  be 
-considered  is  position,  the  general  principles  of  which  are  the 
same  for  each  of  the  above  classes,  and  which  may  be  briefly 
stated  as  follows : 

1st.  Artillery  should,  if  possible,  overlook  all  the  ground  with- 
in range  over  which  an  enemy  might  advance,  and  the  pieces 
be  so  placed  as  to  sweep  the  entire  surface  with  their  fire,  those 
of  longest  range  occupying  the  most  commanding  positions. 

2d.  All  the  lines  of  approach  of  the  assailant  should  be  swept 
not  only  by  the  frontal,  but  b)r  the  flank  or  cross-fire  of  the 
assailed. 

3d.  The  features  of  the  ground  should  screen  the  assailed  from 
the  assailant's  view,  and  afford  cover  from  his  fire  whilst  that  of 
the  assailed  can  be  delivered  with  full  effect. 

4th.  The  position  should,  if  possible,  present  natural  obstruc- 
tions to  the  advance  of  the  assailant. 

5th.  It  should  offer  no  obstructions  to  the  free  movements  of 
the  assailed,  either  for  the  offensive  or  defensive,  and  should 
afford  facilities  for  active  offensive  movements  at  the  opportune 
moment. 

6th.  It  should  have  secure  supports,  both  on  its  flanks  and  in 
the  rear. 

7th.  It  should  afford  every  convenience  for  encamping  and 
being  supplied. 

601.  Intrenched  camps.  Troops,  when  within  striking  dis- 
tance of  the  enemy,  should,  to  avoid  the  consequences  of  a  sur- 
prise, be  encamped  always  in  order  of  battle.  The  modern 
practice  of  armies  is  to  intrench,  if  encamped  even  for  one  night. 
Such  intrenchments  are  usually  of  the  slightest  and  most  hastily- 
■constructed  kind,  merely  sufficient  to  afford  shelter  against  a 
ciight  attack.    The  artillery  in  this  case  is  only  that  usually  ac- 


INTRENCHED   CAMPS.  36S 

companying  troops  on  the  march,  and  for  it  gun-pits  will  suf- 
fice. These  are  made  by  simply  throwing  up  the  earth  in  front 
of  each  piece  so  as  to  form  for  it  a  crescent-shaped  epaulment.. 
If  rails  or  any  similar  material  are  convenient,  a  slight  revet- 
ment may  be  constructed  to  support  the  earth  on  the  side  toward* 
the  piece.  In  dry  weather  the  earth  may  be  dug  from  the  inside 
and  thrown  up  in  front,  thus  forming  a  depressed  position  or 
hole  for  the  piece  to  stand  in.  The  chest  of  the  limber  will  hold 
sufficient  ammunition  for  immediate  use.  To  protect  it,  the 
limber  is  turned  with  its  pole  ./row*  the  piece,  and  is  covered  with 
an  epaulment  similar  to  that  for  the  gun ;  or,  removing  the  horses,, 
it  may  be  backed  up  near  to  and  on  one  side  of  the  piece,  occupy- 
ing with  the  latter  a  portion  of  the  gun-pit.  The  caissons,  horses, 
and  other  material  of  the  battery  may  be  placed  in  some  shel- 
tered position  a  little  way  to  the  rear.  The  positions  occupied 
by  artillery  on  such  a  line  ought  to  be  those  that  would  be  se- 
lected for  it  on  any  well-arranged  line  of  battle. 

When,  in  consequence  of  attack  by  the  enemy,  or  of  his 
threatening  attitude,  the  army  stands  upon  the  defensive,  the 
slight  intrenchments  of  a  temporary  camp  are  increased  and 
strengthened  until  they  become  a  strong  intrenched  line  of 
battle. 

602.  The  gun-pits,  which  before  were  separate  for  each  piece, 
are  now  united  by  a  continuous  epaulment,  and  an  interior  re- 
vetment of  logs,  rails,  watling,  or  sods  is  given  to  it.  All  woods 
within  musket  range  in  front  of  the  line  are  slashed,  for  the 
double  purpose  of  destroying  them  as  cover  for  the  enemy  and 
for  transforming  them  into  an  entanglement  difficult  for  him  U> 
pass.  This  work  is  done  by  the  infantry,  the  artillery  having  its 
full  share  of  labor  in  intrenching  the  batteries. 

An  army  taking  up  a  defensive  position,  intrenches  itself  in 
the  manner  above  described.  When  such  a  line  is  attacked,  and 
the  assault  is  repulsed,  the  assailing  force  falls  back  to  the  nearest 
cover,  and  there,  hugging  the  ground  closety,  usually  intrenches 
itself.  To  accomplish  this,  the  men  use  their  bayonets,  tin  cups, 
or  in  fact  anything  for  loosening  and  throwing  up  the  soil.  Only 
a  few  minutes  are  thus  required  bjr  veteran  soldiers  for  cover- 
ing themselves.  This  line  grows  by  degrees  into  a  formidable 
epaulment,  along  which,  in  positions  the  most  advantageous,  the 
discomfited  assailant  places  his  artillery,  the  intrenchments  for 
which  are  similar  to  those  just  described. 

In  these  positions  the  opposing  forces  remain,  usually  expend- 
ing, without  much  effect,  a  large  amount  of  ammunition,  until 
one  or  the  other  withdraws  for  the  purpose  of  making  a  new 
move.    The  operation  of  withdrawing  is  one  of  great  delicacy,. 


366  DETACHED   WORKS. 

and  is  generally  performed  at  night  with  all  possible  secrecy. 
The  artillery  commanders  at  such  times  have  to  exercise  great 
«;are  and  foresight,  that  their  batteries  may  take  the  proper 
routes  and  not  obstruct  their  own  movements  or  those  of  other 
troops.  An  officer  from  each  battery  should  make  himself 
familiar  with  the  road  to  be  taken  by  it,  and  act  as  its  guide. 

603.  Detached  works  are  those  that  are  situated  beyond  the 
range  of  fire  of  any  other  works,  and  which,  for  their  security, 
have  to  rely  upon  their  own  strength  and  resources. 

The  object  of  such  works  is  to  defend  and  hold  isolated 
points  that  are  of  importance;  such  as  railroad  or  other  bridges, 
mountain  passes,  narrow  defiles,  fords,  points  upon  rivers  to 
-close  them  against  the  passage  of  hostile  vessels,  <fcc.  The  char- 
acter and  extent  of  a  work  of  this  class  will  depend  upon  the 
degree  of  importance  attached  to  the  object  for  which  it  is  con- 
structed, the  amount  of  force  available  for  its  occupancy,  and 
the  nature  of  the  locality.  In  every  instance,  artillery  would 
form  an  important  element  in  its  means  of  defense,  and  the  posi- 
tion of  the  work  should  be  selected  so  as  to  allow  free  use  of  it. 

Works  of  this  kind  may  be  classified  under  three  heads : 

1st.  Those  which,  being  secure  on  the  flanks  and  in  the  rear, 
are  assailable  only  in  front.  Under  this  class  may  be  placed 
■open  batteries  located  on  the  banks  of  rivers,  or  at  the  entrance 
of  harbors,  to  prevent  the  passage  of  an  enemy's  vessels. 

2d.  Those  which  are  assailable  in  front  and  on  the  flanks,  but 
not  in  rear. 

3d.  Those  which  are  assailable  on  all  sides. 

604.  First  class.  This  is  applicable  to  narrow  defiles  where 
the  flanks  are  secure  against  being  turned.    {Fig.  1,  Plate  57.) 

When  the  width  of  the  defile  is  not  greater  than  1800  yards, 
the  line  may  be  a  straight  one  (AB)  for  infantry,  with  short  ad- 
vanced lines  on  the  flanks,  a^  represented  in  the  figure,  for  artil- 
lery. Should  the  conformation  of  the  ground  be  not  suitable  for 
placing  artillery  precisely  as  represented  in  the  figure,  then  the 
most  commanding  position  on  some  other  part  of  the  line  will  be 
-selected  for  it,  bearing  in  mind  always  to  secure  as  far  as  possi- 
ble cross-fire  over  the  ground  in  front.  When  the  defile  exceeds 
1800  yards  in  width,  a  cremaillere  or  serrated  line  is  adopted,  and 
on  it  the  artillery  is  disposed  as  represented  in  Fig.  2,  Plate  57. 

605.  Second  class.  The  plan  of  works  of  the  second  class 
admits  of  great  variety,  depending  on  the  extent  of  the  position. 
The  most  simple  is  that  of  a  work  of  only  two  faces,  the  salient 
being  towards  the  assailant's  line  of  approach.  This  work  is 
termed  a  redan.  (Fig.  3,  Plate  57.)  AB,  gorge;  AC  and  BD, 
faces ;  C  D,  pan-couple ;  B  E,  a  small  flank  sometimes  used. 


STRENGTH    OF   GARRISON.  367 

The  faces  should  receive  such  direction  as  to  sweep  the  .ap- 
proaches to  the  flanks  of  the  position.  As  many  pieces  as  possi- 
ble are  placed  in  the  salient,  and  others  disposed  along  the  faces 
in  the  most  commanding  positions  for  sweeping  the  ground  in 
their  front.  The  angle  formed  at  the  salient  by  the  faces  should 
never  be  less  than  60°.     This  rule  is  general  for  all  salients. 

606.  When  the  flank  approaches  extend  somewhat  to  the 
rear,  (as  in  Fig.  4,  Plate  57,)  a  flank  is  added  to  each  face  of  the 
redan ;  it  then  becomes  a  lunette.  The  flanks  receive  such  direc- 
tions as  will  sweep  by  their  Are  that  portion  of  the  flank  ap- 
proaches which  cannot  be  reached  from  the  faces  except  by  a 
very  oblique  fire.  BC  and  CD  are  the  faces;  AB  and  DE,  the 
flanks. 

The  artillery  is  placed  in  position  at  the  salients,  in  each  of 
which  is  a  pan-couple. 

607.  Third  class.  The  works  comprised  in  this  class  are 
termed  inclosed  works ;  as,  being  assailable  on  all  sides,  they 
must,  for  security,  present  a  complete  line  throughout  to  any 
assault. 

These  works  may  be  divided  into  three  orders :  1st.  Polygonal 
works )  or  redoubts  ;  2d.  TenaiUed  works,  or  star  forts  ;  3d.  Bas- 
tioned  works. 

608.  Redoubts.  These  are  poljfgonal  figures  having  any 
number  of  sides;  and  when  the  site  is  horizontal,  or  sensibly  so 
within  cannon  range,  there  is  no  reason  for  adopting  any  other 
than  a  regular  polygon  for  a  plan.  The  most  simple,  and  the 
one  usually  taken,  is  the  square,  (Fig.  5,  Plate  57,)  the  angles 
of  which  are  formed  into  pan -couples  for  the  reception  of 
artillery. 

The  size  to  be  given  to  a  redoubt,  or  generally  to  any  inclosed 
work,  will  depend  upon  the  number  of  men  available  for  its 
defense,  taking  it  as  an  established  rule  that  it  is  better  to  have 
a  force  concentrated  than  too  much  distributed,  and  therefore 
injudicious  to  make  works  of  a  greater  extent  than  can  be  well 
manned  and  vigorously  defended.  The  number  of  men  will 
depend  upon  the  particular  circumstances  of  the  case ;  as,  for 
instance,  its  situation  with  regard  to  distance  from  the  enemy ; 
whether  it  is  likely  to  be  attacked  by  a  powerful  force  or  only 
by  raiding  parties ;  whether  it  Is  of  such  vital  importance  as  to 
require  it  to  be  held  at  all  hazards,  and  its  distance  from  sup- 
porting force. 

609.  Strength  of  garrison.  One  double-rank  file — that  is, 
two  men  —  is  required  for  the  defense  of  every  lineal  yard  of 
parapet ;  the  number  of  yards  in  the  crest-line  of  any  redoubt 
should  not,  therefore,  exceed  half  the  number  of  men  to  be  con- 


368  STAR   FORTS. 

taincd  in  it.  This  number  makes  allowance  for  the  sick  and  the 
various  details  and  duties  which  deplete  the  effective  strength  of 
garrisons. 

For  the  actual  defense  of  lines,  with  modern  arms,  one  man 
per  lineal  yard  is  ample. 

Eveiy  man  in  an  inclosed  work  requires  for  lodging- room  3 
square  yards  of  the  interior  space ;  that  space,  clear  of  the  ban- 
quette, magazines,  gun  spaces,  and  traverses,  must  not  therefore 
contain  less  than  three  times  as  many  square  yards  as  the  number 
of  men  to  be  contained  in  it.  From  these  considerations  it  fol- 
lows :  1st.  To  find  the  least  number  of  men  sufficient  to  man 
the  parapet  of  an  inclosed  work,  multiply  the  number  of  yards 
in  the  crest-line  by  2.  2d.  To  find  the  greatest  number  of  men 
that  an  inclosed  work  can  accommodate,  find  in  square  yards 
the  area,  clear  of  the  banquette,  magazines,  and  traverses,  and 
divide  this  number  by  3. 

Each  gun  requires  300  square  feet;  this  multiplied  by  the 
number  of  guns  must  be  subtracted  from  the  whole  interior 
space. 

In  estimating  for  the  number  of  men  required  for  any  given 
length  of  interior  crest-line,  no  account  is  taken  of  the  space 
taken  up  by  guns,  as  the  number  of  men  required  for  each  piece 
is  about  equal  to  the  infantry  allowance,  i.  e.,  two  for  each  lineal 
yard  occupied  by  the  piece. 

The  minimum  length  of  side  for  a  square  redoubt  capable  of 
holding  artillery  is  40  yards ;  this  gives  a  work  capable  of  con- 
taining one  field-piece  at  each  angle  and  about  250  men. 

The  redoubt  has  sectors  without  fire,  except  that  delivered 
from  the  pan-couples,  and  is  without  flanking  arrangements. 

610.  Star  forts.  A  star  fort  in  plan  consists  of  a  polygon 
having  alternately  salient  and  reentering  angles.  The  object  of 
this  disposition  is  to  obtain  cross-tires  on  the  approaches  to  the 
salients.  The  simplest  form  of  the  star  fort  is  planned  by  plac- 
ing redans  on  the  middle  of  the  faces  of  a  square  redoubt,  (Fi<j. 
6,  Plate  57,)  thus  giving  alternate  salients  of  90  degrees  and  60 
degrees.     A B O D,  square  redoubt ;  abed,  redans. 

The  guns  would  naturally  occupy  the  pari-coupees  of  the  at- 
tached redans,  and  likewise  those  of  the  square.  The  star  fort, 
from  its  imperfect  flanking  dispositions,  is  but  little,  if  at  all, 
superior  in  strength  to  the  redoubt.  For  the  same  interior  space 
for  the  uses  of  the  garrison,  the  star  fort  presents  a  much  longer 
line  of  parapet  to  be  defended  than  the  redoubt.  It  is  therefore 
only  on  irregular  sites  or  broken  ground  that  application  of  it 
will  be  found  advantageous. 

Remarks. — Since  the  introduction  of  modern  improved  arms. 


i. 


BASTIONED   FORTS.  369 

but  little  regard  has.  been  given  to  flanking  arrangements  in  field- 
works,  experience  having  developed  the  fact  that  they  are  of  very 
little  practical  advantage.  Lines  and  groups  of  works  are  now 
laid  out  so  as  to  cover  each  other  by  flank  and  cross-fire. 

A  work  entirely  detached  should,  however,  have  within  itself 
flanking  arrangements. 

611.  Bastioned  forts.  The  bastioned  fort  has  been  devised 
to  remedy  the  defective  flankiug  dispositions  of  the  preceding 
classes  of  works. 

This  fort  may  consist  of  a  polygon  of  any  number  of  sides,  but 
for  field  forts  the  square  and  pentagon  are  generally  preferred, 
on  account  of  economy  of  labor  in  construction.  To  plan  a  work 
of  this  kind,  a  square  (AB  K,  &c,  Fig.  1,  Plate  58)  or  a  pentagon 
is  laid  out,  and  the  sides  bisected  by  perpendiculars ;  a  distance 
(C  D)  equal  to  one-eighth  of  the  side  is  set  off  on  the  perpendic- 
ular in  the  square,  or  one-seventh  in  the  pentagon;  from  the 
angular  points  of  the  polygon,  lines  (AG  and  HB)  are  drawn 
through  the  points  thus  set  off;  these  lines  give  the  direction  of 
the  lines  of  defense;  from  the  salients  of  the  polygon  distances 
(AE  and  FB)  equal  to  two-sevenths  of  the  side  are  set  off  on  the 
directions  of  the  lines  of  defense,  giving  the  faces;  from  the 
extremity  of  the  faces  the  flanks  (E  H  and  F  Or)  are  drawn  per- 
pendicular to  the  line  of  defense  of  the  other  face  of  the  same 
front ;  the  extremities  of  the  flanks  are  connected  by  a  straight 
line  termed  the  curtain. 

A  B  is  the  exterior  side ;  H,  the  angle  of  the  curtain ;  C  D,  the 
perpendicular;  HB,  the  line  of  defense;  A,  the  salient  angle; 
A  E,  the  face ;  F,  the  shoulder  angle ;  E  H,  the  flank ;  B  P,  the 
capital;  HG,  the  curtains;  GO,  the  gorge  of  bastion;  CAE, 
the  diminished  angle. 

The  side  of  the  polygon  is  termed  the  exterior  side;  the  line 
bisecting  it,  the  perpendicular;  the  angle  at  the  salient  is  the 
flanked  angle;  the  one  formed  by  a  face  and  flank,  the  shoulder 
angle;  the  one  between  the  flank  and  curtain,  the  angle  of  the 
curtain;  the  line  bisecting  a  bastion,  the  capital;  the  portion  of 
the  work  included  between  the  capitals  of  two  adjacent  bastions 
is  denominated  a  bastioned  fronts  or  simply  a  front;  the  interior 
space  of  the  work  not  included  in  the  bastions  is  called  the 
parade. 

Remark. — The  foregoing  nomenclature  applies  also  to  perma- 
nent works.  In  the  latter  class  the  parapet  is  generally  much 
above  the  parade.  The  space  behind  the  parapet  for  the  accom- 
modation of  the  guns  is  termed  the  terre-plein,  which  is  united 
with  the  parade  by  earthen  slopes  or  vertical  walls.  Communi- 
cation with  the  parade  and  terre-plein  is  generally  provided  for 

24 


370  BASTIONED   PORTS. 

by  means  of  roadways  termed  ramps.  The  whole  mass  of  struct- 
ure thus  raised  above  the  parade  is  called  the  rampart. 

An  examination  of  the  arrangement  of  a  bastioned  front  shows 
that  there  are  neither  dead  angles  nor  sectors  without  fire ;  that 
the  salients,  and  all  the  ground  within  range  of  fire,  are  pro- 
tected by  columns  of  direct,  flank,  and  cross  fire. 

Permanent  fortifications  are,  when  the  site  admits  of  it,  con- 
structed on  the  bastioned-front  principle,  and  generally  have 
auxiliary  outworks,  which  are  usually  omitted  in  field-works. 
The  object  for  which  permanent  works  arc  erected  is  to  afford  a 
powerful  artillery  fire,  and  the  entire  interior  crest  may,  there- 
fore, be  occupied  by  cannon.  In  field-works  the  proportion  of 
artillery  is  less,  and  is  usually  disposed  of  by  placing  a  piece  in 
each  pan-couple,  two  or  more  on  each  face  and  one  on  each 
flank,  leaving  the  curtains  entirely  free  for  infantry.  Siege 
howitzers,  when  used,  are  placed  on  the  flanks,  where  their 
capacity  for  firing  canister  is  most  serviceable  in  sweeping  the 
ditch  in  front  of  the  opposite  face.  Machine  guns  occupy  a  like 
position. 

The  sides  of  the  potygon  upon  which  a  bastioned  fort  is  laid 
off  should  not  exceed  600  yards,  nor  be  less  than  125  yards.  If 
greater  than  the  former,  the  range  from  the  flanks  will  be  too 
great  to  cover  properly  the  salients  of  the  bastions ;  if  less  than 
125  yards,  the  flanks  will  be  too  short  for  efficiency,  and  the 
bastions  too  restricted  in  space  for  artillery. 

Calling  the  exterior  side  X,  the  parts  of  the  front  will  be  as 
follows : 

Line  of  defense=0.71804  X     Diminished  angle  =14°  2'  10" 

Face     .    .    .    =0.2857    X     Salient  angle    .    =61°  55' 40" 

Flank  .    .    .    =0.10808  X     Shoulder  angle  .  =118°  4'  20" 

Curtain     .    .    =0.39320  X     Curtain  angle   .    =104°  2' 10" 

Gorge   .    .    .    =0.18279  X 

The  entire  front  is  equal  to  X  multiplied  by  1.1824. 

With  a  pentagon  the  above  numbers  are  slightly  changed,  but 
so  slightly  as  to  make  no  appreciable  difference  when  estimating 
the  dimensions  of  the  sides  of  a  pol5fgon  for  a  bastioned  work  to 
accommodate  a  specified  number  of  men.  In  making  an  esti- 
mate for  the  number  of  men  required  to  man  the  parapet  of  a 
work,  no  allowance  is  made  for  the  space  occupied  by  guns ;  this, 
for  the  reason  that  the  number  of  men  so  required  is  about  equal 
to  that  of  infantry  for  the  same  space ;  that  is,  two  men  for  each 
lineal  yard  of  interior  crest. 

F 

The  foregoing  is  expressed  by  X=g  x  y  x  1  1824 

In  which  F  =  the  number  of  men ;  S  =  the  number  of  sides 


BASTIONED   FORTS.  371 

of  the  polygon ;  and  N  =  the  number  of  men  per  yard  of  interior 
crest ;  X  being,  as  before,  the  exterior  side. 

In  actual  field  service,  it  seldom  happens  that  the  ground  will 
admit  of  a  bastioued  work  constructed  on  a  regular  polygon: 
but  whatever  it  may  be,  the  foregoing  principles  will  apply  and 
give  a  close  approximation  to  the  size  ol  the  required  work. 

To  ascertain  the  number  of  men  required  to  man  a  given 
work,  measure  the  interior  crest  (in  yardd)  and  multiply  by  2. 

Allowing  two  men  for  each  yard  of  parapet,  the  exterior  sides 
of  a  square  bastioned  fort  to  accommodate  4000  men  would  be 
422.8  yards. 

A  fair  proportion  of  artillery  for  a  work  requiring  4000  men 
would  be  36  guns,  disposed  of  as  represented  in  the  figure— t. 1., 
one  in  the  salient  of  each  bastion ;  one  on  each  flank ;  one  in 
the  shoulder  angle,  and  two  on  eaoh  face. 

A  bastioned  work  constructed  on  a  square  of  125  yards  will 
accommodate  about  1180  men  and  an  armament  of  8  pieces. 

612.  For  ordinary  field-works  the  pieces  would  generally  be 
those  on  traveling  carriages,  and  consequently  readily  moved 
from  one  part  of  the  work  to  another,  as  required  by  the  nature 
of  the  attack.  As  a  general  rule,  the  heaviest  pieces  would  be 
placed  in  the  salients,  and  howitzers,  if  used,  in  the  flanks  to 
sweep  the  ditch  with  canister. 

Machine  guns  are  especially  adapted  to  the  defense  of  field- 
works,  and  should  never  be  omitted  as  part  of  the  armament. 
Being  breech-loading  and  easily  handled,  they  require  but  little 
exposure  either  for  themselves  or  the  cannoneers.  The  oscillat- 
ing apparatus  with  which  they  are  provided  allows  the  fire  to  be 
delivered  in  a  horizontal  line,  which  is  superior  to  the  cone  of 
dispersion  of  canister  from  howitzers  or  guns.  When  practica- 
ble, the  machine  gun  should  be  fired  from  a  platform ;  but  as 
the  piece  is  light  and  the  recoil  small,  the  platform  may  be  slight 
and  laid  without  counter-slope.  As  a  general  rule,  all  platforms 
for  pieces  on  traveling  carriages  should  be  laid  horizontally,  as 
this  enables  them  to  be  fired  in  any  direction  with  equal  facility. 
A  bag  of  earth  placed  at  a  proper  distance  behind  each  wheel 
will  check  recoil. 

Since  the  fire  of  the  Gatling  gun  is  that  of  infantry  alone,  its 
introduction  should  not  diminish  the  amount  of  artillery  prop- 
erly requisite  for  a  work.  Machine  guns  may  partly  replace 
infantry,  but  not  artillery. 

Whenever  practicable,  mortars  should  constitute  a  part  of  the 
armament  of  field-works.  These  should  be  placed  in  such  posi- 
tions, usually  behind  traverses,  as  not  to  prevent,  by  their  blast, 


372  LINES   OF  WORKS. 

any  portion  of  the  parapet  from  being  occupied  by  guns  or 
infantry. 

In  actual  service  it  seldom  occurs  that  the  configuration  of  the 
ground  admits  of  works  being  laid  out  with  the  exact  dimensions 
and  figures  above  described.  These  are  intended  to  illustrate 
general  principles  capable  of  being  modified  and  adapted  to  suit 
each  particular  case.  The  plan  of  the  work  should  be  adapted  : 
1st.  To  the  natural  form  of  the  site,  taking  advantage  of  all 
undulations  to  diminish  the  labor  of  construction ;  2d.  To  the 
object  in  view ;  3d.  The  time  available  for  construction  and  the 
number  of  men  to  form  the  garrison. 

The  prolongation  of  all  the  principal  lines  of  a  work  should  be 
directed  as  much  as  possible  on  ground  inaccessible  to  the  ene- 
my, or  at  least  where  he  cannot  obtain  an  enfilade  fire  with  his 
artillery. 

When  circumstances  permit,  a  field  fort  should  be  constructed 
with  such  care  that  the  enemy  will  be  forced  to  abandon  an 
attempt  to  storm  it  and  be  obliged  to  resort  to  the  method  of 
regular  approaches  used  in  the  attack  of  permanent  works.  To 
effect  this,  no  ground  around  the  fort  within  range  of  cannon 
should  offer  shelter  to  the  enemy  from  its  fire ;  the  ditches 
should  be  flanked  throughout,  and  the  relief  be  so  great  as  to 
preclude  any  attempt  at  scaling  the  work.  Approaches  to  it, 
particularly  on  the  salients,  should  be  obstructed  by  abattis* 
fraise,  wire  entanglements,  &c. 

613*  Lines  of  works.  (Figs.  2  to  5,  Plate  58.)  When  it  is  nec- 
essary to  hold  for  a  time  a  line  of  considerable  extent  by  a  force 
inferior  to  that  which  may  be  brought  against  it,  the  line  should 
be  fortified  by  intrenchments,  consisting  of  a  series  of  works 
laid  out  according  to  the  foregoing  principles.  The  kind  of 
work  for  any  particular  position  on  the  line  will  depend  upon 
the  nature  of  the  locality  it  is  to  occupy  and  the  manner  in 
which  it  will  combine  with  those  adjacent  in  securing  mutual 
support  throughout.  Such  lines  are  frequently  from  fifteen  to 
twenty,  or  even  thirty  miles  in  length,  extending  over  every 
variety  of  country,  and  in  their  construction  call  for  the  highest 
skill  in  military  engineering. 

They  are  constructed,  usually,  either  for  the  protection  of 
important  towns,  cities,  and  depots ;  or  to  make  secure  the  base 
of  operations  and  lines  of  communications  of  an  army  maneu- 
vering in  the  field ;  or,  by  stretching  across  peninsular  regions, 
to  restrict  the  theatre  of  operations  of  the  enemy ;  or  for  sur- 
rounding and  besieging  a  place ;  or  for  the  purpose  of  holding 
the  enemy  in  position  with  a  part  of  an  army  while  the  remain- 
der makes  a  flank  or  other  strategic  movement.    The  civil  war 


LINES   OF  WORKS.  878 

of  1861-65  afforded  numerous  instances  of  each  of  these  condi- 
tions. 

The  same  general  principles  apply  to  lines  as  to  other  field- 
works;  but  from  their  great  extent  they  usually  receive  only  a 
alight  relief,  and  the  simplest  angular  figures  are  adopted  for 
their  plan.  In  laying  them  out,  advantage  should  be  taken  of  all 
the  natural  features  presented  by  the  position,  so  as  to  diminish 
the  labor  of  erecting  artificial  ones. 

The  flanks  of  a  line  or  position  are  generally  weak  points. 
When  possible,  one  or  both  should  rest  on  natural  points  of  sup- 
port. A  flank  not  so  supported  must  be  secured  by  strong  works 
especially  well  garnished  with  artillery. 

A  point  that  has  not  a  clear  field  of  fire  is  a  weak  point,  and 
should  be  strongly  intrenched,  so  that  the  enemy  may  not  have 
advantage  of  hills,  ravines,  or  other  shelters  in  approaching  the 
line.  Care  should  be  exercised  in  determining  the  kind  of  artil- 
lery for  such  positions.  The  field  of  fire  being  contracted,  long 
range  is  not  of  so  much  importance  as  ability  to  search  behind 
the  enemy's  shelter,  or  to  throw  a  great  mass  of  projectiles  in  a 
limited  time.  Mortars,  howitzers,  and  machine  guns  will  be 
found  serviceable. 

In  establishing  a  line  of  works,  the  main  object  should  be  to 
cover  every  portion  of  the  front  within  range  with  direct  or 
cross  fire.  To  accomplish  this,  all  prominent  points  along  the 
line  are  fortified,  each  with  a  work  having  a  trace  most  suited  to 
the  conformation  of  that  particular  site.  The  most  important  of 
these  should  be  inclosed  works  upon  the  bastion-front  principle, 
and  of  considerable  size,  capable  of  enduring  an  independent 
attack. 

Smaller  inclosed  works,  such  as  redoubts  and  star  forts,  occupy 
the  secondary  points.  Between  the  works  thus  located  extend 
rifle-4renches  capable  of  sheltering  infantry.  The  line  is  there- 
fore composed  of  a  series  of  works  mutually  supporting  each 
other  and  covering  every  avenue  of  approach. 

The  artillery,  of  which  there  should  be  an  abundance,  will 
naturally  be  placed  in  the  works  occupying  the  most  command- 
ing and  salient  positions.  These  works  should  never  be  so  far 
apart  as  to  be  out  of  mutual  flanking  range  of  the  artillery  with 
which  they  are  armed.  It  is  the  duty  of  officers  of  artillery  to 
cooperate  with  those  of  engineers  in  selecting  the  positions  of 
the  works  that  are  to  be  armed  with  artillery,  and  to  determine 
the  kind  and  quantity  to  be  placed  in  each. 

As  infantry  troops  constitute  the  chief  garrison  of  works  of 
this  nature,  they  will  be  required  to  construct  them,  leaving  to 
the  artillery  the  construction  of  magazines,  embrasures,  plat- 


374  LINES   OF  WORKS. 

forms,  and  other  accessories  pertaining  to  their  special  arm. 
Generally  these  works  are  thrown  up  very  hastily,  and  often 
when  an  immediate  attack  is  apprehended ;  this,  to  a  considera- 
ble extent,  decides  not  only  the  nature  of  the  works,  but  the 
parts  of  them  that  require  the  first  attention.  Subsequently,. 
if  time  permits,  they  are  strengthened,  improved,  and  worked 
into  better  shape. 

As  far  as  practicable,  the  line  should  be  composed  of  inclosed 
works,  for  the  reason  that  should  the  enemy  concentrate  and 
break  through  at  any  point,  he  will  not  be  able  to  sweep  the  line 
to  the  right  and  left  by  taking  it  in  flank  and  rear.  To  storm 
and  capture  each  work  in  succession  would  be  an  operation  too 
costly  for  him  to  undertake. 

It  is  advisable  in  most  instances  to  have  in  front  of  the  line, 
within  easy  musket  range,  a  line  of  small  redans  or  lunettes  at 
intervals  of  about  1500  yards.  Each  of  these  should  be  capable 
of  holding  from  one  to  two  hundred  infantry  and  four  to  six 
field-pieces.  This  line  of  outworks  would  form,  as  it  were,  a 
species  of  picket  line,  keeping  the  enemy  from  closely  observing 
and  harassing  the  main  line,  and  would  constitute  an  advanced 
line  of  battle,  against  which  the  first  shock  of  the  enemy  is  par- 
tially thrown  away,  and  he  dare  not  attempt  to  neglect  them ; 
for  an  endeavor  to  penetrate  through  the  intervals  would  expose 
his  flanks  to  a  close  and  deadly  flank  and  cross  fire.  The  redans 
being  open  towards  the  main  line,  could  not  be  held  if  captured 
by  the  enemy. 

A  somewhat  similar  line  of  works  should  be  established  in  rear 
of  the  main  line.  They  should,  however,  have  their  gorges  stock- 
aded or  otherwise  closed  to  prevent  the  enemy,  should  he  suc- 
ceed in  forcing  his  way  through  the  main  line,  from  obtaining 
easy  possession  of  them  by  the  rear.  Sites  for  them  should  be 
selected  with  a  view  of  obtaining  from  them  a  searching  fire  of 
the  front  line  in  reverse.  This  line  of  works,  although  appar- 
ently inert  in  rear,  must  be  kept  fully  armed  and  manned,  ready 
to  drive  the  enemy  from  any  part  of  the  main  line  that  he  may 
succeed  in  obtaining  possession  of. 

Prominent  salients  in  .the  main  line  are  especially  inviting  to 
the  enemy ;  behind  these  a  second  line  should  be  prepared,  so 
placed,  if  possible,  that  should  the  enemy  obtain  the  main  line 
he  will  be  within  musketry  range  of  the  second,  and  be  forced 
with  wearied  troops  to  undertake  the  capture  of  it. 

614*  An  approximate  estimate  of  the  number  of  troops  re- 
quired to  man  such  a  system  of  intrenchments  may  be  obtained 
by  allowing  300  men  per  mile  for  the  first  or  redanline,  4000  for 


LINES   OF  WORKS.  375 

the  main  line,  300  for  the  rear  line,  and  1200  for  reserves;  mak- 
ing a  total  of  5800  per  mile  of  actual  lighting  force. 

The  amount  of  artillery  required  will  depend  upon  such  cir- 
cumstances as  the  kind  employed ;  the  kind  and  quantity  brought 
up  by  the  enemy ;  the  nature  of  the  country,  and  the  quality  of 
the  troops  on  either  side.  From  four  to  five  pieces  per  thousand 
infantry  is  a  fair  estimate. 

To  break  a  line  of  works  the  enemy  would  secretly  concentrate 
as  powerful  a  force  as  possible  and  assault  some  particular  part 
of  the  line.  As  it  would  be  impracticable  to  have  at  every  part 
of  the  line  a  force  capable  of  successfully  resisting  such  a  con- 
centration, the  probabilities  are  that  he  would  succeed  in  his 
assault,  if  vigorously  made.  To  dislodge  him  from  any  portion 
he  might  thus  capture,  it  is  advisable  to  hold  strong  reserves  of 
both  artillery  and  infantry  at  central  and  convenient  points  in 
rear  of  the  line  of  works.  One  reserve  of  say  5000  infantry  and 
20  field-pieces  for  each  four  miles  of  line  would  make  it  almost 
impossible  for  an  enemy  of  ordinary  strength  to  hold  any  part 
of  it  that  he  might  capture.  Telegraphic  communication  should 
be  established  from  one  reserve  to  another  and  to  every  part  of 
the  line.  This  would  insure  a  prompt  cooperation  of  all  the 
forces. 

In  tracing  field-works,  care  must  be  taken  to  direct,  as  much 
as  possible,  their  faces  upon  ground  least  accessible  to  an  enem}r, 
so  as  to  reduce  to  a  minimum  the  effect  of  his  enfilade. 

615.  When  the  importance  of  the  case  demands  it  and  the 
means  are  available  for  carrying  it  out,  lines  of  field-works  some- 
times assume — as  was  the  case  during  the  rebellion — a  semi- 
permanent character.  These  are  laid  out  with  great  care  and 
constructed  with  skill  and  nicety;  they  are  furnished  with  sub- 
stantial and  commodious  magazines  and  bomb-proof;  the  slopes 
are  sodded  and  the  revetments  constructed  for  endurance. 
Works  of  this  character  are  frequently  armed  with  the  heaviest 
classes  of  ordnance,  the  emplacement,  care,  and  preservation  of 
which,  together  with  the  ammunition  therefor,  will  be  governed 
by  the  same  rules  as  for  permanent  works. 

616*  The  camps,  parks,  trains,  hospitals,  depots,  &c,  should 
be  sufficiently  far  to  the  rear  to  be  out  of  range  from  the  fire  of 
the  enemy,  and  should  have  through  communication  to  the  vari- 
ous parts  of  the  line  bj'  means  of  well-constructed  roads.  These 
roads  should  be  laid  out  in  such  manner  as  to  be,  as  much  as 
possible,  out  of  view  of  the  enemy.  The  horses  of  the  artillery 
in  the  workR,  with  their  drivers,  and  all  parts  of  the  batteries 
not  absolutely  required  for  the  efficient  service  of  the  guns, 
should  be  encamped,  as  above,  in  rear.    The  cannoneers,  offi- 


376  DISTANCES — PARAPET. 

cers,  and  non-commissioned  officers  will  invariably  remain    in 
the  works,  ready  for  action  at  any  moment. 

61*7.  Distance  of  works  from  towns,  cities,  fyc.  Rifled  artil- 
lery, of  large  calibre,  is  capable  of  doing  great  damage  to  towns, 
cities,  dock-yards,  and  other  objects  of  large  extent,  up  to  a  dis- 
tance of  five  miles.  A  few  pieces  of  enormous  calibre  have  been 
constructed  capable  of  throwing  huge  projectiles  to  a  distance  of 
about  nine  mile?.  These  are,  however,  exceptions,  and  as  they 
can  be  made  available  only  by  means  of  a  certain  class  of  almost 
impracticable  vessels,  it  is  not  necessary,  at  present,  to  embrace 
them  in  this  consideration.  Five  miles  being  the  limit  within 
which  the  enemy  must  not  be  allowed  to  establish  his  batteries, 
the  distance  of  defensive  works  within  this  limit  will  depend 
upon  the  character  and  power  of  the  artillery  with  which  they 
can  be  armed.  Heavy  calibres  are  more  capable  of  keeping  an 
enemy  at  a  distance  than  small  calibres,  and  rifles  are  superior 
to  smooth-bores.  About  two  miles  is  the  limit  of  effective  range 
against  ships  of  war,  and  beyond  this  distance  it  would  be  im- 
possible to  prevent  an  enemy  from  carrying  on  operations  by 
land ;  this,  therefore,  is  the  maximum  distance  that  it  is  admis- 
sible to  subtract  from  the  five-mile  limit  of  the  enemy.  In  other 
words,  if  an  enemy  is  able  to  bring  heavy  rifle  guns  against  a 
large  object,  as  a  city  or  a  dock-yard,  works  for  its  protection 
should  be  at  least  three  miles  distant  therefrom.  No  such  area 
can  therefore  be  surrounded  and  protected  by  a  line  of  works 
of  less  extent  than  18  miles ;  generally  it  would  be  much  more, 
depending  upon  the  size  of  the  city,  town,  or  other  objects. 

618.  Parapet.  In  field  fortifications  the  main  features  are 
the  covering  masses  of  earth  of  which  they  are  constructed,  and 
which  are  intended  to  shelter  the  assailed  from  the  view  and  fire 
of  the  assailant.  When  the  covering  mass  is  so  constructed  as 
to  afford  the  assailed  a  view  and  fire  over  the  assailant's  line  of 
approach,  it  is  termed  a  parapet;  when  intended  simply  as  a 
screen  or  cover  from  the  fire  of  the  enemy,  it  is  termed  an  epaul- 
ment;  and  when  used  to  cover  troops  or  guns  from  an  enfilading 
fire  on  the  flank  or  in  the  rear,  a  traverse. 

The  simplest  form  of  work  is  the  rifle-trench  or  pit.  (Figs.  1 
and  2,  Plate  59.) 

In  this,  the  parapet  is  formed  by  throwing  the  earth  from  a 
trench  within  to  the  front.  The  earth  thus  thrown  up,  together 
with  the  depth  of  the  trench,  affords  the  desired  shelter.  The 
troops  stand  or  squat  in  the  trench  and  deliver  their  fire  over 
the  bank  of  earth  in  front.  This  method  of  intrenching  affords 
the  speediest  means  of  obtaining  cover,  and  is  the  one  resorted 
to  when  troops  are  under  fire,  or  when  they  intrench  their  camp 


PARAPET.  377 

or  position  for  a  temporary  stay.  Rails,  logs,  in  fact,  almost 
anything  at  hand  may  b:*  used  as  a  rough  interior  revetment 
for  sustaining  the  earth.  For  artillery,  the  trench  is  made  some- 
what wider  than  is  necessary  for  infantry. 

619.  In  the  more  elaborate  class  of  field  fortifications,  such 
as  the  inclosed  works  previously  mentioned,  the  earth  to  form 
the  parapet  is  taken  from  the  exterior,  thus  forming  in  front  of 
the  parapet  a  ditch  which  makes  a  formidable  obstacle  in  the 
way  of  an  assailant  attempting  to  enter  the  work  by  escalade. 

Fig.  3,  Plate  59,  shows  the  usual  form  of  the  profile  of  such  an 
Intrenchraent  in  ordinary  soil. 

BCDEPG,  profile  of  parapet ;  H  I  K  L,  profile  of  ditch ;  M 
N  O,  profile  of  glacis;  A  B,  terre-plein,  or  parade;  B  C,  ban- 
quette slope,  having  a  slope  of  one  upon  two ;  C  D,  tread  of  the 
banquette,  having  a  slope  to  the  rear  of  two  inches ;  D  E,  inte- 
rior slope,  having  a  slope  of  three  upon  one ;  E  F,  superior  slope, 
having  a  slope  of  one  upon  four  to  six ;  F  G.  exterior  slope,  having 
a  slope  of  one  upon  one ;  G  H,  berm  ;  H  I,  scarp,  having  a  slope 
of  about  two  upon  one ;  I K,  bottom  of  ditch  ;  K  L,  counterscarp, 
having  a  slope  of  about  two  upon  one ;  B,  foot  of  the  banquette 
slope  ;  C,  crest  of  the  banquette ;  D,  foot  of  the  interior  slope ;  E, 
interior  crest ;  F,  exterior  crest ;  G,  foot  of  the  exterior  crest ; 
H,  crest  of  the  scarp ;  I,  foot  of  the  scarp ;  K,  foot  of  the  coun- 
terscarp ;  L,  crest  of  the  counterscarp ;  M,  foot  of  the  glacis ;  N", 
crest  of  the  glacis ;  a  6,  thickness  of  the  parapet.  The  tread  of 
the  banquette  is  placed  4  feet  3  inches  below  the  interior  crest. 

The  following  table,  giving  the  slope  for  various  degrees  of 
elevation,  will  prove  useful. 

By  referring  to  tables  of  ranges,  and  bearing  in  mind  that  the 
angle  of  fall  of  a  projectile  is  always  greater  than  the  elevation 
of  the  piece,  the  table  will  also  afford  useful  suggestions  and 
data  with  reference  to  defilading  works. 

In  seeking  protection  from  the  fire  of  an  enemy,  either  by  nat- 
ural or  artificial  cover,  the  drop  of  the  projectile  must  be  taken 
into  account.  This  depends  upon  the  range,  kind  of  piece  used, 
and  nature  of  fire  employed. 

The  table,  furthermore,  furnishes  useful  assistance,  when 
studying  defensive  positions,  as  to  locating  batteries  and  deter- 
mining the  kind  of  artillery  to  be  placed  at  the  various  points 
for  reaching  ground  that  may  be  occupied  by  the  enemy,  and 
which  is  sheltered  by  undulations  or  by  timber  growth  from  view 
from  the  work. 

In  connection  with  this,  see  par.  650  and  tables  of  ranges  for 
the  8-inch  and  100-pounder  rifles. 


378 


DITCH. 


Angle. 

Rise.  ' 

i 

1  Angle. 

Rise. 

i 

Anqle. 

Rise. 

Angle. 

Risk. 

Deg. 

One  on.1 

Deg. 

One  on. 

Deg. 

One  on. 

Deg. 

One  on. 

1 

57.3— 

9 

6.3+ 

17 

3.2+ 

25 

2.1 

2 

28.6+ 

10 

5.7+ 

18 

3.0+ 

26 

2.0 

3 

19.0+ 

11 

5.1+ 

19 

2.9— 

27 

1.9 

4 

14.3— 

12 

4.7  + 

20 

2.7+ 

28 

1.85 

5 

11.4+ 

13 

4.3+ 

i      21 

2.6 

29 

1.80 

6 

9.5— 

14 

4.0+ 

1      22 

2.5— 

30 

1.75 

7 

8.1+ 

15 

3.7+ 

1      23 

2.3+ 

8 

7.1+ 

16 

3.5- 

'      24 

1 

2.2 

The  dimensions  of  the  parapet  will  depend  upon  the  kind  of 
earth  used  and  the  time  and  means  that  can  be  employed  in  its 
construction,  together  with  the  time  that  the  work  is  to  remain 
occupied,  and,  finally,  with  the  time  and  meaus  the  enemy  can 
dispose  of  in  the  attack,  and  the  degree  of  resistance  the  work 
should  offer.  The  relief,  which  is  the  vertical  height  (E  a) 
of  the  parapet  above  the  terre-plein,  should  not  be  less  than  8 
feet,  and  it  will  be  seldom  necessary  or  expedient  to  exceed  12 
feet.  Its  thickness,  which  is  the  horizontal  distauce  (a  b)  be- 
tween the  interior  and  exterior  crests,  is  regulated  by  the  kind 
of  earth  used  and  the  kind  of  attack  it  is  expected  to  meet.  If 
it  is  to  resist  artillery,  the  thickness  is  that  given  in  par.  596,  in 
which  the  minimum  is  laid  down  at  14  feet. 

The  relief  of  a  work,  or  of  any  part  of  a  work,  is  its  height 
above  the  ground  on  which  it  stands. 

The  command  of  a  work  is  its  elevation  with  reference  to  the 
surrounding  country,  especialty  that  within  striking  distance, 
which  may  be  occupied  by  an  enemy. 

620.  Ditch.  The  dimensions  of  the  ditch  should  be  regulated 
to  furnish  the  earth  for  the  parapet.  To  present  a  respectable 
obstacle  to  the  enemy,  its  depth,  however,  should  not  be  less  than 
6  feet,  nor  its  width  at  the  top  less  than  12  feet.  For  approxi- 
mate purposes,  the  dimensions  of.  a  ditch  to  supply  earth  neces- 
sary for  a  given  parapet  may  be  obtained  by  assuming  the  depth 
of  the  ditch  and  dividing  the  area  of  the  profile  of  the  parapet  by 
it  to  obtain  the  width. 

In  turning  the  salients,  keeping  the  dimensions  of  the  ditch 
the  same,  there  will  be  an  excess  of  earth,  —  a  circumstance 
which  may  be  taken  advantage  of  by  making  the  parapet  thicker 
in  these  parts.  Due  allowance  must  be  made  for  this  when  lay- 
ing out  the  work.  The  salients  should  always  be  the  thickest 
and  strongest. 

621.  Tracing.    In  laying  out  the  figure  of  a  work  on  the 


SOD   REVETMENT.  379 

ground,  which  operation  is  called  tracing,  the  interior  crest  is 
taken  as  the  governing  line ;  all  other  lines  are  laid  off  with  ref- 
erence to  it. 

Profiling.  The  trace  being  laid  off  and  marked  by  stakes  at 
the  angles,  profiles  of  the  parapet,  {Fig,  1,  Plate  60,)  constructed 
of  strips  of  light  wood,  are  set  up  at  the  angles,  and  at  other 
points  along  the  parapet  where  long  stretches  of  the  latter  occur* 
The  method  of  establishing  these  profiles  will  readily  suggest 
itself. 

When  strips  of  wood  are  not  easily  obtained,  stoat  cord  may 
be  used  instead,  the  cord  being  attached  to  the  uprights  at  the 
points  where  the  strips  of  wood  are  or  would  be  nailed. 

When  a  sufficient  portion  of  the  profiling  is  completed,  work- 
ing parties  are  set  to  work  excavating  the  ditch  and  forming  the 
parapet.  The  latter,  as  the  work  progresses,  should  be  well 
rammed.  If  the  soil  is  stony,  the  vegetable  mould  on  the  sur- 
face should  be  removed,  and  reserved  to  form  the  top  of  the  par- 
apet. This  should  always  be  free  from  stones  to  a  depth  of  at 
least  three  feet,  to  prevent  injury  to  the  troops  from  the  effect 
of  shot  striking  and  scattering  the  pebbles  and  fragments. 

Those  portions  of  an  earth-work  within  effective  range  of  the 
enemy's  artillery,  and  upon  the  endurance  and  integrity  of 
which  depend  the  support  and  safety  of  valuable  batteries  or 
magazines,  should  be  made  strongest  by  additional  thickness  and 
height.  The  material  and  workmanship  should  be  of  the  best 
quality. 

It  is  almost  impossible  to  make  a  breach  in  a  work  constructed 
of  sand  of  sufficient  thickness  to  prevent  penetration  through 
and  through  it  and  having  flat  slopes  towards  the  breaching 
batteries  of  the  assailant.  In  such  cases  the  sand  displaced  by 
successive  shots  falls  back  again  and  again  within  the  area 
attempted  to  be  breached. 

622*  Revetments.  A  revetment  consists  of  a  facing  of  stone, 
wood,  sods,  or  other  material  to  sustain  an  embankment  which 
has  a  slope  steeper  than  the  natural  slope  of  the  particular  kind 
of  earth  used. 

In  field-works,  revetments  are  used  only  for  the  interior  slope 
of  the  parapet  and  for  the  scarp.  For  the  first,  sods,  palisades, 
fascines,  logs,  gabions,  and  plank  are  chiefly  used ;  and  for  the 
last,  timber. 

623*  Sod  revetment.  Sod-work  forms  a  strong  and  durable 
revetment.  The  sods  should  be  cut  from  a  well-clothed  sward, 
with  the  grass  of  a  fine  short  blade  and  thickly-matted  roots. 
If  the  grass  is  long  it  should  be  mowed  before  the  sod  is  cut.. 


380  FASCINE   REVETMENT. 

The  more  tenacious  the  soil  the  better  will  be  the  sods.  Those 
-cut  from  sandy  localities  are  of  but  little  value. 

Sods  are  of  two  sizes:  one.  termed  strechers,  are  12  inches 
square  and  4J  inches  thick ;  the  other,  termed  headers,  are  18 
inches  long,  12  inches  broad,  and  4J  inches  thick. 

The  sod  revetment  (Fig.  2,  Plate  60)  is  commenced  as  soon 
as  the  parapet  is  raised  to  the  level  of  the  tread  of  the  banquette. 
A  course  of  sods  is  then  laid,  either  horizontal  or  a  little  inclined 
from  the  banquette.  The  course  consists  of  two  strechers  and 
one  header  alternating,  the  end  of  the  header  being  laid  to  the 
front;  the  grass  side  is  laid  downwards,  and  the  sods  should 
protrude  a  little  beyond  the  line  of  the  interior  slope,  for  the 
purpose  of  trimming  the  course  even  at  top,  before  laying  an- 
other, and  to  make  the  interior  slope  regular.  The  course  is 
firmly  settled  by  tapping  with  a  spade  each  sod  as  it  is  laid,  and 
the  earth  of  the  parapet  is  packed  closely  behind  the  course.  A 
second  is  laid  on  the  first  so  as  to  break  joints  with  it.  The  top 
course  is  laid  with  the  grass  side  up,  and  in  some  cases  pegs  are 
driven  through  the  sods  of  two  courses  to  connect  the  whole 
more  firmly.  When  cut  from  a  wet  soil,  the  sods  should  not  be 
laid  until  they  are  partially  dried ;  otherwise  they  will  shrink 
and  the  revetment  crack  in  drying.  In  hot  weather  the  revet- 
ment should  be  watered  frequently  until  the  grass  puts  forth. 
Sod  revetment,  on  account  of  its  durability  and  freedom  from 
splinters,  is  the  best  of  all  revetments. 

Log  revetment.  {Fig.  3,  Plate  60.)  This  revetment  is  made 
of  trunks  of  small  trees  or  saplings  laid  horizontally  one  on  the 
«>ther  and  supported  by  posts  set  into  the  banquette.  At  fre- 
quent intervals  tie  beams  are  dovetailed  between  the  logs,  and, 
extending  six  or  eight  feet  into  the  parapet,  are  secured  to 
horizontal  anchoring  logs.  For  intrenchments  hastily  thrown 
up,  this  is  the  most  usual  form,  rails  or  timber  of  any  kind  being 
used. 

624.  Fascine  revetment.  A  fascine  (Fig.  4,  Plate  60)  is  a 
bundle  of  twigs  closely  bound  together.  There  are  two  sizes  of 
fascines :  one  size  is  9  inches  in  diameter  and  about  10  feet  long; 
the  other,  which  is  generally  termed  a  soucisson,  is  12  inches  in 
diameter  and  20  feet  long.  It  is  chiefly  used  for  the  revetments 
of  batteries. 

To  make  a  fascine  straight  twigs  are  selected,  between  the 
thickness  of  the  little  finger  and  thumb, — the  longer  the  better. 
They  should  be  stripped  of  the  smaller  twigs.  A  support,  term- 
ed a  fascine-horse,  (Fig.  5,  Plate  60.)  is  put  up  by  driving  two 
stout  stakes  obliquely  into  the  ground  about  two  feet,  so  as  to 
oross  each  other  about  two  feet  above  the  ground,  where  they 


GABION   REVETMENT.  381 

are  firmly  lashed  together.  A?  many  of  these  supports  as  may 
be  required  are  put  up  in  a  straight  line,  about  18  inches  apart. 
This  forms  the  horse,  on  which  the  twig*  are  laid  to  be  bound 
together. 

A  machine  (C  D)  termed  a  fascine  choker  is  formed  of  two 
stout  levers  about  5  feet  long,  connected  near  their  extremities 
by  a  chain  or  strong  rope,  which  must  be  long  enough  to  pass 
once  around  the  fascine  and  be  drawn  tight  by  means  of  the 
levers. 

The  twigs  are  laid  on  the  horse  with  their  large  and  small 
ends  alternating;  the  choker  is  applied  to  bring  them  together, 
and  they  are  bound  by  wire,  or  by  withes  made  of  tough  twigs, 
properly  prepared  by  twisting  over  a  blaze,  so  as  to  render  them 
pliable.  The  ties  are  placed  12  inches  apart,  and  every  third  or 
fourth  one  should  be  made  with  an  end  about  three  or  four  feet 
long,  having  a  loop  at  the  extremity  to  receive  a  stake  through 
it.  This  stake  is  termed  an  anchoring  stake,  its  object  being  to- 
secure  the  fascine  firmly  to  the  parapet. 

To  form  the  revetment,  the  first  row  of  fascines  is  imbedded 
{Fig.  4,  Plate  60)  about  half  its  thickness  below  the  tread  of  the 
banquette,  and  is  secured  by  means  of  the  anchoring  stakes,  and 
also  by  several  stakes  driven  through  the  fascine  itself  about  12 
inches  into  the  earth.  The  knots  of  the  ties  are  laid  inside,  and 
the  earth  of  the  parapet  is  well  packed  behind  the  fascine.  A 
second  row  is  laid  on  the  first,  so  as  to  give  the  requisite  interior 
slope ;  it  should  break  joints  with  the  first  row,  and  be  connected 
with  it  by  several  stakes  driven  through  them  both.  The  other 
rows  are  laid  with  similar  precautions,  and  the  parapet  is  usually 
finished  at  the  top  by  a  course  of  sods. 

625*  Post  revetment.  (Fig.  6,  Plate  60.)  This  is  construct- 
ed of  posts  from  4  to  6  inches  in  diameter,  cut  into  lengths  of  5.5 
feet,  and  set  with  proper  slope,  in  close  contact,  in  a  trench  two- 
feet  in  depth,  at  the  foot  of  the  breast-height.  The  tops  of  the 
posts,  if  not  already  so,  are  sawed  off  level,  to  receive  a  horizon- 
tal capping  piece,  which  is  spiked  on.  Anchor  ties  are  dove- 
tailed into  the  cap  and  secured  to  an  anchor  log  imbedded  in  the 
parapet.  On  top  of  the  cap  are  laid  several  courses  of  sods,  rais- 
ing the  interior  crest  to  the  proper  height.  With  a  good  quality 
of  timber  this  revetment  is  durable.  It  is  easily  constructed,  and 
next  to  sods  is  the  best. 

G2G.  Gabion  revetment.  (Fig.  7,  Plate  60.)  The  gabion  is 
a  basket  of  a  cylindrical  form,  open  at  each  end.  Its  height  is 
usually  2  feet  9  inches,  and  diameter  2  feet. 

To  form  a  gabion,  a  directing  circle  is  made  of  two  hoops,  the 
difference  between  their  radii  being  such  that,  when  placed  con- 


382  PLANK   REVETMENT — SAND-BAGS. 

•centrieally,  there  shall  be  about  If  inches  between  them.  They 
are  kept  in  this  position  by  placing  small  blocks  of  wood  between 
them,  to  which  they  are  tied  with  pack-thread.  The  directing 
circle  is  placed  on  the  ground,  and  seven  or  nine  stakes,  about 
1  inch  in  diameter  and  3  feet  long,  are  driven  slightly  into  the 
ground  between  the  hoops,  at  equal  distances  apart ;  the  directing 
circle  is  then  slipped  up  midway  from  the  bottom,  and  tied  in 
that  position.  Twigs  about  half  an  inch  in  diameter,  and  as  long 
as  they  can  be  procured,  are  wattled  between  the  stakes  like  or- 
dinary basket-work.  When  finished  to  within  about  2  inches  of 
the  top,  the  gabion  is  placed  with  the  other  end  up,  the  directing 
circle  taken  off,  and  the  gabion  completed  to  within  2  inches  of 
the  other  extremities. of  the  stakes.  The  wicker-work  at  the  two 
ends  is  secured  by  several  withes,  and  the  ends  of  the  pickets  are 
sharpened.    The  gabion  is  then  ready  for  use. 

To  form  the  revetment,  a  fascine  is  first  laid  partly  imbedded 
below  the  tread  of  the  banquette ;  (Fig.  4,  Plate  60;)  the  gabion, 
which  is  placed  on  end,  rests  on  this,  so  as  to  give  it  the  requisite 
tilope ;  it  is  then  filled  with  earth ;  others  are  placed  in  like  man- 
ner, and  the  parapet  is  raised  behind  them ;  another  fascine  is 
laid  on  top,  and  in  some  cases  two. 

In  making  gabions,  iron  hoops,  similar  to  barrel  hoops,  may 
"be  used  instead  of  wattling.  The  number  of  stakes  should  be 
increased  to  eleven  or  thirteen.  Gabions  made  either  of  wattlings 
or  hoops  are  not  good  for  holding  dry  sand. 

Sheet-iron  is  preferable  to  either  iron  hoops  or  brush  for  ga- 
bions. For  this  purpose  rectangular  sheets  of  suitable  dimen- 
sions to  form  cylinders  of  the  same  height  and  diameter  as  the 
ordinary  gabion,  are  prepared  with  three  holes  punched  near  to 
and  parallel  with  the  shorter  sides  of  the  sheets.  These  are  to 
secure  the  ends  with  wire  when  the  sheet  is  bent  into  the  cylin- 
drical form.  The  advantages  of  this  description  of  gabion  are 
greater  strength,  lightness,  and  durability  than  either  of  the 
other  two,  offering  great  facility  for  transportation,  and  resist- 
ing better  the  blast  of  guns  when  used  for  reveting  the  cheeks 
-of  embrasures.  Galvanized  iron  is  less  liable  to  rust  than  plain 
iron ;  when  not  galvanized,  the  gabions  should  be  lacquered  with 
<5oal-tar. 

627*  Plank  revetment.  This  may  be  made  by  setting  stoat 
posts  of  scantling  about  3  feet  apart,  2  feet  below  the  tread  of 
the  banquette,  giving  them  the  same  inclination  as  the  interior 
slope.  Behind  these  stakes  boards  are  nailed  to  sustain  the 
-earth.  The  posts  should  be  securely  anchored  into  the  parapet 
with  wire  and  stakes. 

628.  Sand-bags  are  sometimes  used  for  revetments  when 


SCARP  REVETMENT.  388 

other  materials  cannot  be  procured ;  though  their  object  in  moat 
oases  is  to  repair  damages  done  by  the  enemy's  fire.  They  are 
made  of  canvas,  or  a  good  quality  of  gunny-cloth,  sewed  with 
ootton  twine  with  lock-stitch ;  the  bag,  when  empty,  is  2  feet  8 
inches  long  and  1  foot  4  inches  wide.  When  filled  and  laid  they 
occupy  a  space  of  6  by  10  by  24  inches,  and  contain  0.85  of  a  cubic 
foot  of  sand,  weighing  about  85  pounds.  Thirty-two  make  a  cubic 
yard. 

The  bags  are  laid  as  headers  and  strechers,  either  in  the  Eng- 
lish or  Flemish  bonds.  They  should  not  be  more  than  three- 
fourths  full  when  laid ;  if  full,  they  do  not  lay  well,  and  are  more 
liable  to  burst  on  becoming  wet,  or  under  great  pressure.  When 
time  is  of  importance,  the  bags  need  not  be  tied,  but  the  throat 
is  given  a  twist  and  turned  under  the  end  of  the  bag  as  it  is  laid. 
To  prevent  decay,  they  should  be  payed  with  coal-tar  before  be- 
ing filled  or  before  being  laid ;  this,  furthermore,  renders  them 
less  liable  to  take  fire  when  dry.  One  hundred  and  forty-four 
sand-bags,  laid  as  above,  make  ten  superficial  yards  of  revetment. 

Sand-bag  reveting  requires  less  anchoring  to  make  it  stand 
than  any  other.  If  the  reveting  is  kept  wet,  the  sand  will  not 
so  readily  escape  through  rents,  nor  will  the  bags  take  fire  from 
the  blast  of  the  pieces ;  this,  however,  hastens  their  decay.  From 
six  to  ten  months,  depending  upon  usage,  is  the  duration  of 
reveting  made  of  sand-bags.  When  used  near  the  muzzle  of 
the  piece  in  the  revetment  of  embrasures,  they  soon  wear  away, 
from  the  blast  of  the  piece,  unless  well  protected. 

629*  Scarp  revetment.  (Fig.  1,  Plate  61.)  This  revetment  is 
serviceable  where  the  foot  of  the  scarp  is  subject  to  wash,  as  in  a 
wet  ditch.  It  is  formed  of  a  frame-work  of  heavy  timber,'  and  is 
used  chiefly  for  important  field  forts.  A  piece,  termed  a  cap,  is 
imbedded  in  a  trench  made  along  the  line  of  the  berme ;  other 
pieces,  termed  land-ties,  are  placed  in  trenches  perpendicular  to 
the  cap,  with  which  they  are  connected  by  a  dovetail  joint; 
they  are  about  8  or  10  feet  apart.  Cross-pieces  are  halved 
into  the  land-ties  near  their  extremities,  and  two  square  piles, 
about  5  feet  long,  are  driven  in  the  angles  between  the  land- 
ties  and  cross-pieces;  inclined  pieces,  serving  as  supports  to  the 
-cap,  are  mortised  into  its  under  side  at  intervals  of  8  or  10  feet. 
These  supports  usually  receive  a  slope  of  ten  perpendicular  to 
one  base;  they  rest  on*a  groundsill  at  the  bottom  of  the  ditch, 
to  which  they  are  mortised,  this  sill  being  held  firm  by  square 
piles. 

Behind  this  frame-work  thick  plank  or  heavy  scantling  are  plac- 
ed horizontally,  having  the  same  slope  as  the  supports ;  or  else  a 
rabbet  may  be  made  in  the  cap  and  ground-sills,  and  the  scant- 


384     INTERIOR  ARRANGEMENTS — BARBETTE. 

ling  let  in  between  these  two  pieces,  serving  as  a  support  to  the 
cap.  This  is  the  more  difficult  construction,  but  the  better, 
since,  should  the  heavy  supports  be  cut  away,  the  cap  will  still 
be  retained  in  its  place. 

In  constructing  the  scarp  revetment  the  cap-sill  and  land-ties 
are  first  laid,  and  then  a  narrow  trench  is  dug  to  the  bottom  of 
the  ditch  to  allow  the  ground-sill  and  frame- work  to  be  set  in. 

In  many  of  the  earth-works  constructed  during  1861-65  the 
berme  was  dispensed  with,  the  exterior  slope  being  continued 
down  to  the  bottom  of  the  ditch.    This  plan  worked  successfully. 

When  circumstances  admit  of  it,  all  the  slopes  of  an  earth- 
work should  be  sodded,  or  else  be  manured  and  sowed  with 
grass  seed. 

630.  Interior  arrangements.  Under  this  head  come  batteries, 
magazines,  traverses,  bomb  and  splinter  proofs,  and  interior 
redoubts. 

631  •  Batteries.  The  term  battery,  in  this  connection,  is 
usually  applied  to  a  place  in  a  work  prepared  for  the  accommo- 
dation of  several  guns.  It  is  also  used  when  speaking  of  tbe 
arrangements  made  of  a  parapet  to  enable  the  guns  to  fire  over 
it  or  through  openings  in  it;  as,  a  barbette  battery,  an  embrasure 
battery,  <fcc. 

632.  Barbette.  This  is  a  construction  by  means  of  which  a 
piece  can  fire  over  a  parapet.  It  consists  of  a  mound  of  earth 
thrown  up  against  the  interior  slope ;  the  upper  surface  is  level, 
and  2  feet  9  inches  below  the  interior  crest,  for  light  field- 
pieces,  and  from  4  to  6  feet  for  heavy  guns.  If  the  barbette 
is  raised  behind  a  face,  its  length  should  be  sufficient  to  allow  16 
(or  18)  feet  along  the  interior  crest  for  each  gun  ;  and  its  depth, 
or  the  perpendicular  distance  from  the  foot  of  the  interior  slope 
to  the  rear,  should  be  24  feet.  The  earth  of  the  barbette  at  the 
rear  end  receives  the  natural  slope.  To  ascend  the  barbette  a 
ramp  is  made  of  earth,  connecting  the  top  of  the  barbette  with 
the  terre-plein.  The  ramp  is  10  feet  wide  on  the  top,  and  its 
slope  is  six  base  to  one  perpendicular.  The  earth  at  the  sides 
receives  the  natural  slope.  The  ramp  should  be  at  some  con- 
venient point  in  the  rear,  and  take  up  as  little  room  as  possible. 

633*  As  barbettes  are  usually  placed  in  the  salients,  an  ar- 
rangement is  made  for  guns  to  fire  in  the  direction  of  the  capital. 
The  construction  in  this  case  is  somewhat  different  from  the 
preceding.  A  pan-coupf  (a  b)  of  11  feet  (Fig.  2,  Plate  61)  is  first 
made,  and  from  the  foot  of  its  interior  slope  a  distance  of  24 
feet  is  set  off  along  the  capital ;  at  the  extremity  of  this  line  a 
perpendicular  is  drawn  to  the  capital,  and  5  feet  are  set  off 
on  this  perpendicular  on  each  side  of  the  capital;  from  these 


EMBRASURES.  385 

points  on  the  perpendicular  a  line  ia  drawn  perpendicular  to 
each  face,  respectively ;  the  hexagonal  figure  thus  laid  out  is  the 
surface  of  the  barbette  for  one  gun.  The  ramp  (c)  in  this  case 
is  made  along  the  capital. 

If  three  or  more  guns  are  placed  in  the  salient,  a  pan-coup* 
is  formed  as  in  the  last  case,  (Fig.  3,  Plate  61,)  and  24  feet 
are,  in  like  manner,  set  off  on  tne  capital ;  but  instead  of  pro- 
ceeding as  in  the  last  case,  a  perpendicular  is  drawn  from  this 
point  to  each  face,  and  the  pentagonal  space  thus  inclosed  is 
taken  for  the  gun  in  the  salient;  from  the  perpendicular  last  set 
off,  as  many  times  16  (or  18)  feet  will  be  set  off  on  the  interior 
crest  of  each  face  as  there  are  guns  required.  This  gives  the 
length  of  the  barbette  along  each  face ;  the  depth  is  made  24 
feet,  and  the  two  are  united  in  the  salient.  One  or  more 
ramps  may  be  made,  as  most  convenient. 

The  advantages  of  the  barbette  consist  in  the  commanding 
position  given  to  the  guns,  and  in  a  very  wide  field  of  fire.  On 
these  accounts  the  salients  are  the  best  positions  for  them. 
Their  defects  are,  that  they  expose  the  guns  and  men  to  the 
enemy's  artillery  and  sharp-shooters. 

634.  Embrasures.  The  embrasure  (Fig.  4,  Plate  61)  is  an 
opening  made  in  the  parapet  for  a  gun  to  tire  through.  The 
bottom  of  the  embrasure,  termed  the  sole,  is  2  feet  9  inches, 
or  from  4  to  6  feet  above  the  ground,  on  which  the  wheels 
of  the  carriage  rest,  according  to  the  size  of  the  gun  and  the 
kind  of  carriage.  It  usually  slopes  outward  to  allow  the  gun  to 
be  fired  at  a  depression.  The  base  of  this  slope  should  never  be 
less  than  six  times  the  altitude.  In  most  cases  it  may  be  hor- 
izontal, or  even  have  a  slight  slope  to  the  rear.  The  interior 
opening,  termed  the  mouth,  is  from  18  to  36  inches  wide,  accord- 
ing to  the  calibre  of  the  gun,  and  is  of  a  rectangular  or  trapezoidal 
form. 

The  line  which  bisects  the  sole  in  the  direction  of  the  line  of 
fire  is  called  the  directrix.  The  sides  of  the  embrasure  arc  termed 
the  cheeks;  these  widen  out  towards  the  exterior,  which  widen- 
ing is  termed  the  splay,  the  inclination  upon  each  side  from  the 
directrix  being  one  upon  ten.  They  furthermore  have  an  in- 
clination outwards  from  the  vertical;  this  inclination,  at  the 
line  of  the  exterior  crest,  is  three  upon  one. 

When  the  directrix  is  perpendicular  to  the  interior  crest,  the 
embrasure  is  termed  direct;  (Fig.  4,  Plate  61;)  when  oblique, 
the  embrasure  is  termed  oblique.  (Same  figure.)  In  order  that 
the  part  of  the  embrasure  wnich  is  next  to  the  muzzle  of  the 
gun  may  be  nearly  of  the  same  width  in  both  the  direct  and 

25 


386  EMBRASURES. 

oblique  embrasures,  the  mouth  of  the  latter  is  wider  in  propor- 
tion to  the  obliquity. 

Embrasures  are  reveted  with  the  same  material  and  in  the 
same  manner  as  described  for  the  interior  slope. 

If  the  exact  position  for  the  embrasure  is  known,  it  is  best  to 
lay  it  out  and  make  it  while  the  parapet  is  being  constructed. 
As  soon  as  the  latter  is  built  up  to  the  sill  of  the  future  embra- 
sure, a  light  stake  is  planted  in  line  with  the  interior  slope  on 
each  side  of  the  directrix,  in  such  position  as  to  represent  the 
sides  of  the  mouth  of  the  embrasure ;  a  strip  is  nailed  across  at 
the  proper  height  to  represent  the  sill,  and  another  above  on  the 
line  of  the  interior  crest.  The  earth  being  smoothed  off  to  give 
the  desired  slope  to  the  sole,  the  directrix  is  marked  out  on  it 
by  means  of  a  cord;  the  splay  of  the  cheeks  is  obtained  by 
giving  the  sides  an  inclination  of  one-tenth  with  the  directrix. 
These  lines  being  laid  off  on  the  sole,  the  revetment  is  placed 
along  them  and  is  given  an  inclination  corresponding  with  the 
two  profile  stakes  at  the  mouth,  and  three  upon  one  at  the  exte- 
rior crest.  Should  gabions  be  used  for  reveting  the  cheeks, 
fascines  are  first  partly  imbedded  along  the  edges  of  the  sole, 
and  the  gabions  placed  on  them  in  such  manner  as  to  obtain  the 
proper  flare.  The  gabions  are  held  in  position  by  being  an- 
chored with  telegraph  wire  to  a  beam  of  timber  imbedded  in 
the  parapet  parallel  to  and  about  8  feet  from  the  cheeks  of  the 
embrasure.  The  beams  are  held  by  securing  stakes.  Revet- 
ments made  of  other  material  are  secured  in  a  similar  manner. 
This  precaution  should  be  thoroughly  looked  after  in  the  first 
instance,  because  when  the  revetment  is  broken  by  the  blast  of 
the  gun  or  the  shots  of  the  enemy  it  is  difficult  to  repair  it,  and 
the  necessity  for  repairing  would  probably  come  at  a  time  when 
it  could  not  be  done. 

If  the  embrasure  is  to  be  cut  out  after  the  parapet  is  com- 
pleted, the  mouth  is  marked  off  with  stakes  and  strips  as  before; 
the  earth  is  removed  so  as  to  obtain  approximate^  the  sole, 
which  is  then  laid  off  and  the  work  completed  as  just  described. 

The  sole  of  the  embrasure  should  be  secured  from  being  worn 
away  by  the  blast  with  boards,  poles,  or  some  similar  material 
running  lengthwise  with  the  embrasure.  Raw-hides  will  greatly 
assist  in  preserving  the  revetments  of  the  cheeks  from  the  effects 
of  abrasion  produced  by  firing.    For  this  purpose  the  hide,  while 

freen,  is  stretched,  with  the  flesh  side  outward,  over  the  part  to 
e  protected,  and  is  there  confined  by  stakes  driven  through  it 
'nto  the  parapet. 

The  best  method,  however,  for  securing  the  month  of  the  em- 
brasure, and  the  sole  and  sides  for  5  or  6  feet  from  the  mouth, 


PLATFORMS.  387 

1s  a  lining  made  of  J-inch  boiler  iron.  {Fig.  5,  Plate  61.)  The 
plates  are  cut  to  the  proper  form  to  fit  the  sole  and  cheeks,  and 
are  fastened  together  with  angle-irons  and  rivets.  Wings,  about 
a  foot  wide,  extend  out  on  each  side  against  the  interior  slope  to 
prevent  the  lining  from  being  moved  to  the  front  by  the  blast. 
A  round  bar  of  iron  passes  across  the  top  about  18  inches  from 
ihe  throat;  to  this  a  door  of  sheet-iron  is  suspended,  forming  a 
mantlet  against  musketry.  In  the  centre  of  this  door  is  a  cut  or 
slot,  about  a  foot  high  and  0  inches  wide,  for  the  double  purpose 
of  allowing  the  rammer  to  pass  through  while  loading  the  piece, 
and  for  sighting  it.  A  vertical  lever  of  wood  or  iron  is  fastened 
to  one  side  of  the  door;  to  this  a  rope  is  attached,  so  that  by  pull- 
ing on  it  the  door  is  thrown  up  to  allow  the  piece  to  be  fired. 

That  part  of  the  interior  slope  lying  below  the  mouth  of  the 
embrasure  is  termed  the  genouillere.  The  mass  of  earth  between 
two  embrasures  is  termed  a  merlon. 

The  advantages  of  embrasures  are,  that  the  men  and  guns  are 
less  exposed  than  in  a  barbette  battery.  Their  principal  defects 
are  :  they  have  a  very  limited  field  of  fire ;  the}'  weaken  the  par- 
apet, and  present  openings  through  which  the  enemy  may  pene- 
trate in  an  assault.  Owing  to  their  limited  field  of  fire,  they  are 
generally  used  for  the  protection  of  particular  points ;  as,  to  flank 
a  ditch,  protect  a  salient,  enfilade  a  road,  Ac.  The  most  suitable 
position  for  them  in  a  work  is  on  the  flanks. 

635*  Platforms.  When  a  gun  mounted  on  a  traveling  car- 
riage is  fired  often  in  the  same  direction,  the  ground  under  the 
wheels  is  soon  formed  into  ruts.  It  is  to  prevent  this  that  plat- 
forms of  timber  are  used  in  such  cases.  Those  for  field  service 
are  described  in  par.  254,  et  seq. 

The  shape  of  the  platform  for  works  is  usually  a  rectangle ;  in 
some  cases,  where  a  wide  field  of  fire  is  required,  the  form  is  a 
trapezoid.  The  rectangular  platform  is  10  feet  wide  and  17  feet 
long  for  siege-pieces,  and  9  feet  wide  and  15  feet  long  for  field 
guns.  It  consists  of  three  sleepers  of  6-inch  scantling,  either  15 
or  17  feet  long,  laid  parallel  to  the  directrix  of  the  embrasure 
and  covered  with  2-inch  plank  cut  into  lengths  of  nine  or  ten 
feet.  Between  the  ends  of  the  sleepers  and  the  foot  of  the  gen- 
ouillere a  piece  of  8-inch  scantling  9  feet  long,  termed  a  hurter, 
is  laid ;  it  should  project  about  6  inches  above  the  platform  ana 
be  bisected  by  the  directrix.  The  object  of  the  hurter  is  to  pre- 
vent the  wheels  from  striking  against  the  revetment. 

To  lajr  a  platform,  the  earth  on  which  it  is  to  rest  should  be 
well  rammed  and  leveled.  Three  trenches  arc  then  made  for 
the  sleepers,  two  of  which  should  be  under  the  wheels  and  the 
middle  one  under  the  trail.    The  sleepers  are  laid  flush  with  the 


388  PLATFOEMS. 

ground  and  firmly  secured  by  stakes  driven  at  their  sides  and 
ends,  and  the  earth  is  solidly  packed  around  them.  The  plank* 
are  then  laid  and  secured  by  nails. 

When  the  piece  is  to  be  fired  habitually  in  the  same  direction, 
a  platform  may  be  constructed  of  three  pieces  of  timber,  one 
under  each  wheel  and  one  under  the  trail,  firmly  secured  by 
stakes  and  connected  by  cross-pieces,  into  which  they  are  halved. 

Guns  and  mortars  in  field-works  are  best  in  pairs,  with  trav- 
erses between  each  set  of  pairs.  A  good  platform  for  guns  may 
be  made  of  3-inch  plank  laid  on  timbers  3  feet  apart.  If  lumber 
is  abundant,  it  is  best  to  have  the  planks  extend  over  the  whole 
space  occupied  by  each  pair  of  guns. 

636.  In  many  field-works,  especially  those  erected  for  the 
defense  of  rivers  and  the  entrances  to  harbors  against  armed 
vessels,  artillery  of  the  heaviest  calibre  is  mounted.  The  gen- 
eral features  of  works  for  such  an  armament  are  the  same  as 
those  previously  described  for  light  armament,  but  in  many  of 
the  details— notably  in  the  method  of  mounting  the  guns — there 
are  differences  of  especial  interest  to  artillerists.  As  such  works 
are  intended  to  resist  fire  from  the  heaviest  artillery,  they  should 
receive  the  maximum  thickness  of  parapet.  (Par.  596.)  The 
parapet  is  much  higher,  the  merlons  being  simply  masses  of 
earth  thrown  up  in  mound  shape  and  reveted  on  the  interior 
slope,  without  any  attempt  at  arrangement  for  infant^  fire. 
The  magazines,  traverses,  and  splinter-proofs  are  of  greater  size 
and  thickness.  The  guns  are  mounted  on  iron  carriages  the 
same  as  for  permanent  fortifications ;  the  height  of  these  carri- 
ages admits  of  from  five  to  seven  feet  from  the  interior  crest,  or 
from  the  sill  of  the  embrasure  to  the  top  of  the  platform.  Each 
piece  requires  18  feet  in  width  of  clear  space,  and  in  most  cases 
a  splinter-proof  traverse  should  be  placed  between  each  gun,  or 
pair  of  guns,  and  its  neighbor. 

The  gun  platforms  are  constructed  of  heavy  beams  of  timber 
in  two  or  three  layers,  crossing  each  other  and  firmly  secured 
together  with  iron  bolts.  Plate  62  shows  in  detail  the  construc- 
tion of  the  platform  for  the  8-inch  converted  rifle,  which  is  also 
the  same  for  the  100-pounder  Parrott  and  10-inch  smooth-bore. 

For  the  12-inch  rifle,  the  platform  represented  in  Plate  63  has 
been  proposed  by  the  Engineer  Bureau. 

The  platform  adopted  for  the  15-inch  smooth-bore  (front  pin- 
tle) is  shown  in  Plate  64.  This  platform  is  designed  for  a  carri- 
age with  depressed  traverse  circles,  admitting  oi  the  terre-plein 
being  11  feet  below  the  interior  crest,  thus  giving  increased  se- 
curity to  the  cannoneers. 

Plate  64  shows  the  details  of  construction  of  the  platform 


POWDER   MAGAZINES.  389 

adopted  for  the  15-inch  smooth-bore,  mounted  on  a  centre-pintle 
carriage. 

These  platforms  are  supplied,  when  needed,  by  the  Engineer 
Department.  To  lay  one,  a  pit  of  the  proper  size  is  dug;  the 
bottom  of  it  is  thoroughly  settled  by  ramming,  and  the  platform 
is  laid  in  it,  and  the  earth  filled  in  and  well  rammed  about  the 
timbers.  Great  care  should  be  observed  to  have  the  circles  per- 
fectly level.  Previous  to  laying  the  platform  the  timbers  should 
be  coated  with  coal-tar. 

In  case  of  war  with  any  maritime  power,  it  would  be  necessary 
to  erect  earth-works  of  the  foregoing  character  for  the  protection 
of  our  harbors.  The  permanent  works  constructed  and  intended 
for  that  puipose  were  designed  when  the  10-inch  Columbiad  rep- 
resented artillery  of  the  greatest  power.  Since  then  artillery  of 
a  new  type  and  vastly  greater  power  has  been  introduced,  against 
which  fortifications  of  old  style  are  capable  of  ottering  but  feeble 
resistance.  The  construction  of  these  old  works,  furthermore, 
does  not,  except  to  a  small  degree,  admit  of  the  changes  that 
would  be  necessary  to  adapt  them  for  receiving  armaments  of 
modern  artillery.  An  officer  in  command  of  the  defenses  of  a 
harbor  being  called  upon  to  place  them  in  a  state  of  efficiency, 
would,  therefore,  select  positions  exterior  to  the  permanent 
works,  and  erect  thereon  earth- works  of  the  character  just  de- 
scribed, and  arm  them  with  appropriate  artillery.  The  new 
works  would,  generally,  be  simply  uninclosed  batteries  bearing 
upon  the  channel.  They  should,  if  possible,  hold  defensive  rela- 
tionship with  the  old  works  and  the  latter  be  utilized  as  redoubts, 
armed  with  light  guns  and  musketry,  to  prevent  the  enemy  from 
landing  and  assaulting  the  new  works  in  rear.  The  old  works 
would,  furthermore,  serve  as  places  of  arms  and  depots  secure 
from  capture  by  coup  de  main. 

Whenever  railroad  or  water  transportation  is  available,  artil- 
lery of  heavy  calibre  is  made  use  of  in  siege  operations.  Guns 
thus  used  are  mounted  on  wooden  platforms  of  the  foregoing 
models,  and  placed  in  earth-works  of  the  character  herein  de- 
scribed. 

63*7.  Powder  magazines.  The  main  objects  to  be  obtained 
in  constructing  a  powder  magazine  are,  to  place  it  in  a  position 
convenient  to  the  pieces  to  be  served,  and  one  least  exposed  to 
the  fire  of  the  enemy  ;  to  make  it  shot-proof,  and  to  secure  the 
contents  from  moisture. 

Magazines  are  of  two  kinds :  the  storage  magazine,  in  which 
is  kept  the  general  supply  of  powder  for  the  work,  and  service 
magazines^  which  are  small,  containing  only  a  limited  supply 
for  the  immediate  use  of  a  few  pieces.    The  latter  should  be 


390  STORAGE   MAGAZINE. 

near  the  pieces  to  be  served ;  generally  they  would  be  placed 
In  the  traverses  separating  guns,  or  else  close  in  rear  of  the 
platforms. 

Storage  magazine.  The  size  of  the  storage  magazine  will 
depend  upon* the  number  and  calibre  of  pieces,  in  the  work 
and  the  number  of  charges  to  be  kept  for  each.  This  data 
being  known,  the  amount  of  storage  room  required  will  be  de- 
termined by  allowing  5780  cubic  inches  for  each  barrel  contain- 
ing 100  pounds  of  powder. 

Projectiles  and  cartridges  for  siege  and  field  guns  are  put  up 
in  boxes,  as  explained  in  par.  565,  and  are  stored  in  magazines 
kept  especially  for  this  kind  of  ammunition.  Each  box  of  siege- 
gun  ammunition  contains  four  projectiles  and  four  cartridges,, 
and  measures  about  2950  cubic  inches.  Each  box  of  field-gun 
ammunition,  contains  ten  projectiles  and  cartridges,  and  meas- 
ures about  the  same.  From  this  it  is  easy  to  obtain  the  storage 
capacity  required  for  any  amount  of  these  kinds  of  ammunition. 

The  dimensions  of  the  interior  of  the  magazine  should  be  so 
regulated  as  to  entail  no  unnecessary  loss  of  space  in  storing  its 
contents.  The  exterior  dimensions  of  a  powder  barrel  are: 
Length,  20  inches ;  diameter  at  bilge,  17  inches.  With  the  bar- 
rels stored  in  the  usual  way,  on  the  side,  {Fig.  1,  Plate  65,)  a 
magazine  6  feet  6  inches  high  would  afford  space  for  four  tiers, 
leaving  8  inches  on  top  for  handling  room.  A  magazine  10  feet 
wide  will  give  room  for  four  rows,  ieaving  40  inches  for  passage- 
way; therefore  each  17  inches  of  length  of  a  magazine  10  feet 
wide  by  6.5  feet  high  will  contain  16  barrels.  A  magazine  of 
this  height  and  width  and  30  feet  long  would  store  400  barrels 
and  leave  a  space  of  about  one  yard  in  width,  extending  across 
it,  at  the  entrance. 

At  the  rate  of  100  rounds  for  each  15-inch  gun,  a  fair  allow- 
ance for  such  guns  in  field-works,  a  magazine  of  the  foregoing 
dimensions  will  give  storage  for  a  supply  of  powder  for  four 
pieces.  The  number  of  rounds  per  gun  should  increase  as  the 
calibre  diminishes.  It  would,  however,  seldom  be  necessary  to 
have  more  than  300  rounds  for  any  calibre  above  100-pounders. 
An  ordinary  packing- box  containing  the  number  of  rounds 
before  specified  measures,  in  exterior  dimensions,  19  inches  in 
length,  13.5  inches  in  width,  and  11.5  inches  in  height.  These 
dimensions  allow  the  boxes  to  be  compactly  packed  in  a  maga- 
zine of  any  ordinary  shape,  and  it  requires  only  a  small  calcula- 
tion to  determine  the  storage  room  required  for  any  given  num- 
ber of  rounds  for  guns  of  these  calibres. 

It  is  best  not  to  exceed,  for  any  one  magazine,  the  dimension* 


STORAGE   MAGAZINE.  391 

above  laid  down,  namely,  30  by  10  by  6.5  feet.  Wben  greater 
storage  room  is  required,  two  or  more  should  be  constructed. 

Precautions  to  secure  drainage  are  of  the  utmost  importance. 
Generally  the  ground  is  sufficiently  undulating  to  effect  this  by 
means  of  a  covered  drain  leading  from  the  bottom  of  the  maga- 
zine. Where  this  is  not  practicable,  the  bottom  of  the  excava- 
tion must  be  formed  so  as  to  collect  the  water  at  one  point, 
whence  it  may  be  removed  by  pumping  or  bailing. 

Figs.  1  and  2  illustrate  the  best  method  of  constructing  a  stor- 
age magazine.  The  sides  of  the  interior  of  the  magazine  are 
formed  of  12-inch  logs,  either  square  or  round,  placed  vertically 
in  juxtaposition,  aud  resting  on  a  ground-sill.  These  are  capped 
on  top  by  a  2-inch  plank,  a  strip  of  the  same  being  spiked  on 
within  the  cap.  The  roof  is  formed  of  15-inch  logs,  laid  across, 
in  juxtaposition,  each  having  a  shoulder  of  3  inches  to  fit  it  to  the 
cap  and  inside  strip.  Longitudinal  logs  with  varying  diame- 
ters are  laid  on  these,  so  as  to  give  a  proper  pitch  to  the  roof. 
Earth  is  solidly  packed  upon  the  top  and  between  the  roof  logs, 
receiving  the  proper  slope  for  the  roofing  boards.  These  boards, 
carefully  joined,  are  laid  on  in  two  thicknesses,  each  being  covered 
with  a  coating  of  asphalt  or  coal-tar;  upon  these  boards  rest  the 
covering  of  earth.  The  flooring  is  of  joists  and  boards.  The 
sides  of  the  magazine  are  surrounded  with  an  air-chamber  formed 
of  inclined  logs  supported  on  a  ground-sill  and  resting  against  the 
top  logs ;  these  are  placed  at  three  or  four  feet  apart,  each  one 
being  braced  at  the  middle  to  resist  flexure  from  the  pressure  of 
the  earth.  The  air-chamber  is  covered  in  by  saplings  laid  upon 
each  other  horizontally.  Ventilators  are  placed  between  the 
magazine  and  the  air-chamber,  near  the  top,  and  also  between 
the  latter  aud  the  external  air,  the  two  not  being  opposite,  and 
the  usual  precautions  to  guard  against  sparks,  by  covering  the 
mouth  with  wire  cloth  or  perforated  tin,  are  taken.  The  whole 
is  covered  with  earth,  the  thickness  of  which  will  depend  on  the 
character  of  the  enemy's  artillery.  In  no  case  should  it  be  less 
than  14  feet  on  the  exposed  side ;  10  feet  will  be  sufficient  for 
the  other  sides  and  the  top.  The  entrance  may  be  either  upon 
an  end  or  side,  depending  upon  how  the  magazine  has  been 
located  with  reference  to  the  enera)7.  In  all  cases  the  entrance 
must  be  on  the  side  from  the  enemy,  and  should  be  secured  by 
a  bomb-proof  covering.  The  magazine  chamber  should,  if  prac- 
ticable, be  placed  at  least  two-thirds  of  its  height  below  the  sur- 
face of  the  ground.  The  ammunition  is  stored  and  cared  for  as 
explained  in  par.  569. 

In  this  and  all  similar  structures  railroad  iron  is  a  highly  serv- 


392  SERVICE   MAGAZINES. 

iceable  material  for  roofing,  the  bars  being  laid  in  juxtaposition 
in  place  of  the  logs  before  mentioned. 

Service  magazines.  The  size  of  these  will  depend  upon  the 
number  of  rounds  it  is  desirable  to  have  ready  for  immediate 
use ;  usually,  twenty  rounds  for  sea-coast  guns,  and  from  fifty  to 
a  hundred  for  those  of  smaller  calibre,  will  be  sufficient.  The 
capacity  of  the  magazines  to  hold  this  amount  or  any  other  that 
ma}  be  fixed  upon  will  be  determined  by  the  rules  just  given. 
If  the  magazine  is  to  hold  barrels,  it  should  be  6.5  feet  high  and 
7.5  wide ;  this  will  accommodate  four  tiers  of  three  rows,  leaving 
a  passage-way  of  30  inches.  The  length  will  depend  upon  the 
number  of  barrels,  and  this  will  be  governed  by  the  number  and 
calibre  of  pieces  to  be  provided  for;  generally,  15  feet  will  ho 
ample. 

A  magazine  of  this  description  is  usually  constructed  of  coffer- 
work. 

A  coffer-work  is  formed  by  making  frames  (Fig.  1,  Plate  66)  cor- 
responding in  dimensions  with  the  cross  section  of  the  magazine ; 
each  frame  is  composed  of  two  uprights,  termed  stanchions,  and 
a  cap  and  sill  of  stout  timber  or  scantling,  not  less  than  6-inch. 
The  cap  and  sill  pieces  are  slightly  notched  to  fit  the  stanchions, 
and  all  secured  together  with  nails  or  spikes.  These  frames  are 
placed  upright  and  parallel  to  each  other,  about  2  feet  apart; 
they  are  covered  on  the  top  and  sides  with  2-inch  plank,  termed 
a  sheeting.  The  magazine,  otherwise,  is  constructed  as  in  the  last 
case. 

A  very  good  magazine,  and  one  easiest  of  construction,  is  made 
of  logs  notched  together  at  the  corners  after  the  fashion  of  a  log 
cabin.  (Fig.  2,  Plate  66.)  Other  logs  are  laid  in  juxtaposition 
across  the  top,  and  the  whole  covered  over  with  earth.  This  is 
the  most  substantial  for  those  placed  in  traverses. 

For  field  and  siege  pieces  the  magazines  are  not  required  to  be 
so  large.  A  height  and  width  of  6  feet  with  a  length  of  12  feet 
will  generally  be  sufficient. 

Magazines  of  this  size  may  be  made  as  just  described,  or  they 
may  be  made  of  gabions.  (Fig.  3,  Plate  66.)  When  the  latter 
are  used,  a  hole  is  usually  dug  in  the  ground  to  form  part  of  the 
magazine;  the  gabions  are  placed  in  three  rows,  side  by  side, 
around  the  hole,  and  are  filled  with  earth.  The  top  is  formed 
of  timbers  laid  across  in  juxtaposition  and  covered  with  fascines, 
the  whole  being  covered  with  a  proper  thickness  of  earth.  The 
bottom  is  covered  by  a  flooring  of  joists  and  boards,  a  shallow 
ditch  being  left  under  the  flooring  to  carry  any  water  to  a  drain 
outside.  This,  at  best,  is  but  an  inferior  method  of  constructing 
a  magazine. 


TRAVERSES.  S9S 

Entrances  to  magazines  must  always  be  on  the  side  from  the 
enemy,  and  protected  by  a  splinter-proof  shelter  large  enough 
to  afford  easy  access  to  the  door. 

Splinter-proofs  are  usually  constructed  of  scantling  or  trunks 
of  trees  cut  into  suitable  lengths  and  placed  in  an  inclined  posi- 
tion over  the  magazine  door.  (Fig.  4,  Plate  66.)  The  timbers 
are  placed  side  by  side,  and  covered  with  at  least  two  feet  of 
earth  or  sods. 

To  prevent  rain  from  percolating  through  the  earth  on  top, 
the  magazine  is  covered  with  a  paulin  laid  on  the  earth  and 
secured  with  pickets.  To  prevent  rapid  decay  of  the  paulin,  it 
should  be  payed  with  a  mixture  of  tar  and  grease  boiled  to- 
gether— about  two  parts  of  tar  to  one  of  grease ;  this  composi- 
tion is  applied  to  both  sides.  In  dry  weather  the  paulin  should 
be  removed  to  let  the  earth  dry. 
Boards,  bark,  or  shingles  may  be  used  instead  of  paulins. 
Adjoining  or  near  the  service  magazine  is  a  filling-room,  in 
which'  the  powder  barrels  are  opened  and  the  cartridges  made 
up  and  the  shells  filled.  A  room  10  feet  square  by  6 J  feet  high 
will  generally  be  sufficiently  large.  It  is  constructed  in  the  same 
manner  as  the  magazine,  and  is  fitted  with  shelves,  &c,  for  the 
convenient  keeping  of  primers,  fuses,  implements,  and  other 
small  articles  required  in  making  up  cartridges  and  preparing 
shells. 

While  being  convenient  to  the  magazine,  it  should  be  so  sit- 
uated that  an  explosion  taking  place  in  it  will  not  communicate 
fire  to  the  magazine.  Fig.  2,  Plate  65,  represents  the  ground 
plan  of  one  form  that  may  be  adopted. 

The  powder  is  carried  from  the  magazine  to  the  filling-room 
in  canvas  or  leather  stretchers,  and  only  in  such  quantities  at  a 
time  as  may  be  necessary  for  keeping  the  pieces  served. 

638.  Traverses.  Those  which  are  placed  between  guns  or 
on  their  flanks  to  cover  them  from  an  enfilade  fire,  are  usually 
termed  gabionades. 

To  form  a  gabionade,  gabions  are  placed  in  a  row  {Fig.  5, 
Plate  66)  side  by  side,  inclosing  a  rectangular  space  of  about  15 
feet  in  width  from  out  to  out,  and  about  24  feet  in  length,  per- 
pendicular to  the  parapet.  A  second  row  is  placed  within  this 
and  touching  it,  and  a  third  row  inside  of  the  second.  The  area 
thus  inclosed  is  filled  in  with  earth  to  a  level  with  the  top  of  the 
gabions.  Six  rows  of  large  fascines  are  next  laid  on  the  gabions 
to  support  a  second  tier  consisting  of  two  rows.  The  second  tier 
is  filled  in  like  the  first,  and  the  earth  is  heaped  up  on  top.  Four 
rows  of  large  fascines  are  placed  on  these  to  support  a  third 
consisting  of  one  row,  making  the  gabionade  nearly  12  feet 


394  BOMB-PROOF   SHELTERS. 

high.  The  ends  are  inclosed  by  filling  in  with  gabions,  as  for 
the  sides.  A  passage-way  of  about  two  feet  is  left  between  the 
end  of  the  traverse  and  the  parapet.  This  space  may  be  roofed 
over  with  logs  and  earth  to  form  a  cover  in  which  the  cannon- 
eers may  shelter  themselves  against  fragments  of  shells. 

Splinter-proof  traverses  may  be  made  by  placing  two  thick- 
nesses of  gabions  side  by  side  filled  with  earth,  with  a  second 
tier  of  one  thickness  on  top.  When  a  service  magazine  is  to  be 
placed  in  a  gabionade,  the  rows  of  gabions  are  set  farther  apart, 
and  the  excavation  for  the  magazine  is  made  between  them. 
The  chamber  of  the  magazine  is  constructed  in  one  of  the  ways 
heretofore  described. 

639.  Bomb-proof  shelters.  These  are  for  the  protection  of 
the  troops  when  not  on  duty.  They  should  be  located  on  the 
parade,  convenient  to  the  pieces  to  be  served,  yet  not  so  near  as 
to  interfere  with  the  defense.  They  are  usually  constructed  in 
half  excavation  of  logs  built  up  like  a  log  house,  or  of  a  frame- 
work in  the  manner  shown  in  Fig*  1,  Plate  67,  the  exterior 
side  being  of  heavy  logs  placed  vertically  in  juxtaposition,  rest- 
ing on  a  ground-sill  and  capped  at  top.  Parallel  to  this  is  an- 
other row,  forming  the  other  side,  which  may  also  be  placed  side 
by  side  or  at  short  intervals  apart,  and  capped  like  the  outside 
row.  The  roof,  consisting  of  heavy  logs  laid  in  juxtaposition 
and  covered  with  thick  boards  joined,  rests  on  the  capping,  the 
whole  covered  over  on  the  side  of  the  enemy  with  earth  to  a 
depth  of  at  least  14  feet  from  the  wood-work.  To  prevent  this 
mass  of  earth  from  pushing  the  structure  over  to  the  rear,  one 
in  every  two  or  three  of  the  roof-logs  are  cut  of  sufficient  length 
to  extend  about  8  feet  beyond  the  front  of  the  wall,  and  dove- 
tailed to  a  longitudinal  log  held  in  position  by  vertical  posts,  the 
anchor-log  being  sufficiently  covered  with  earth  to  protect  it 
from  injury  by  shot  from  the  enemy. 

These  bomb-proofs  are  made  to  serve  the  purpose  of  traverses, 
and  are  frequently  arranged  with  a  staging  or  gallery  along  the 
rear  side  for  the  accommodation  of  infantry,  who  deliver  their 
fire  over  the  top,  arranged  for  this  as  a  parapet. 

In  all  interior  arrangements,  system  and  regularity  should  be 
observed  from  the  first ;  otherwise  the  work  will  grow  into  a 
labyrinth  of  confusion  greatly  opposed  to  efficiency  and  comfort, 

640.  Splinter -proofs  made  after  the  foregoing  plan,  but 
smaller,  may  be  placed  against  the  parapet  between  the  guns. 
These  not  only  afford  shelter  for  the  men,  but  give  a  place  to 
keep  implements  and  a  few  rounds  of  ammunition  ready  for 
immediate  use.    Another  convenient  form  of  splinter-proof  may 


BATTERIES.  39& 

be  made  by  leaning  logs  or  rail  road-iron  bars  against  the  sides, 
of  traverses  and  covering  them  over  with  earth. 

Works  exposed  to  anything  like  constant  and  protracted  artil- 
lery fire,  should  be  provided  with  bomb  and  splinter  proof  shel- 
ters sufficient  to  comfortably  lodge  the  entire  garrison.  This  is 
made  more  necessary  now  than  formerly,  from  the  very  great 
range  and  searching  power  of  modern  artillery,  which  makes  it 
impossible  for  a  garrison  to  obtain  rest  without  going  to  too- 
great  a  distance  from  the  work. 

As  a  general  rule,  troops  should,  for  sanitary  reasons,  be 
quartered  as  much  as  possible  outside  of  the  works. 

The  importance  of  protecting  guns  and  their  carriages  with* 
traverses  and  epaulments  bears  an  increasing  ratio  to  the  size- 
of  the  piece. 

Formerlj-,  when  guns  were  comparatively  light,  works  were- 
garnished  with  them  in  great  numbers,  and  the  fact  of  having  a 
few  of  them  disabled  was  of  but  little  consequence ;  it  required 
but  simple  appliances  and  only  a  few  hours  to  replace  them  by 
others.  With  modern  heavy  artillery,  it  is  impracticable  to  have 
many  pieces  in  a  work,  and  when  one  is  disabled  it  requires- 
days  instead  of  hours,  and  the  employment  of  much  machinery 
and  labor,  to  replace  it. 

641.  Batteries.  The  field-work  that  artillery  troops  are  most 
frequently  called  upon  to  construct  is  the  battery.  This  may  be- 
for  one  piece  or  for  several.  Fig.  2,  Plate  67,  represents  a  bat- 
tery for  four  siege-pieces. 

In  this  instance,  the  parapet  (A)  is  made  of  earth  taken  from- 
the  front,  thus  forming  a  ditch  (C).  To  protect  the  pieces 
(XX XX)  from  flanlf  tire,  the  parapet  is  continued  around  on 
one  or  both  ends,  forming  epaulments  (BB).  The  guns  are  in 
paii-s,  separated  by  a  traverse  (D).  The  interval  between  the 
axes  of  the  embrasures  of  each  pair  is  16  feet  for  guns  on  travel- 
ing carriages,  and  from  18  to  22  feet  for  sea-coast  guns.  Be- 
tween the  two  middle  pieces,  this  distance  is  increased  by  the 
thickness  of  the  traverse,  generally  about  15  feet.  The  entire 
length  of  the  interior  crest  of  the  parapet,  from  a  to  6,  will  there- 
fore be  79  feet.  This  and  other  given  dimensions  are  not  abso- 
lute, but  indicate  the  method  of  obtaining  the  data  necessary 
for  laying  out  any  battery.  The  length  of  the  flank  epaulments 
will  depend  upon  the  direction  of  the  enemy's  fire ;  in  all  cases, 
it  must  be  sufficiently  great  to  give  full  protection  to  the  whole 
interior  from  an  enfilading  fire;  generally  it  would  be  about  24 
feet.  The  thickness  of  the  parapet  and  epaulments  will  depend, 
upon  the  power  of  the  artillery  they  are  expected  to  resists 


396  BATTERIES. 

•(See  par,  596.)  The  details  of  the  various  parts  are  the  same  as 
heretofore  given. 

When  the  earth  is  thrown  up  from  the  rear  to  form  the  para- 
pet and  epaulments,  the  work  is  termed  a  sunken  battery.  The 
ditch  (C)  is  then  dispensed  with.  In  many  instances  a  ditch  is 
of  but  little  importance,  and  for  economy  of  labor  the  earth  may 
be  taken  from  both  front  and  rear. 

Embrasures  for  guns  firing  with  great  angles  of  elevation  may 
receive  a  counter-slope,  giving  the  sole  nearly  the  same  inclina- 
tion from  the  sill  upwards  as  the  least  angle  of  elevation  uuder 
which  it  may  be  required  to  aim  the  piece.    (Fig..£,  Plate  61.) 

Batteries  for  even  the  heaviest  pieces  may  be  constructed  on 
marshy  ground  by  laying  a  grillage  of  timber  over  the  surface 
and  building  up  the  parapet  on  it  with  sand-bags.  To  prevent 
the  parapet  from  settling  over  towards  the  front,  the  grillage 
should  extend  several  feet  beyond  it  in  that  direction.  In  or- 
der that  the  platform  of  the  piece  may  not  be  moved  from  its 
true  horizontal  position  by  any  settling  of  the  parapet,  the  space 
to  be  occupied  by  it  is  inclosed  with  strong  sheeting  piles.  In 
this  inclosed  space  several  layers  of  fascines  are  laid,  crossing 
each  other  at  right  angles;  on  these  earth  or  sand  is  rammed, 
and  tne  platform  laid  in  the  usual  manner.  If  sand  is  used 
on  top  of  the  fascines,  two  or  three  thicknesses  of  paulins  should 
be  spread  over  them  to  hold  the  sand.  Magazines  in  such  locali- 
ties must,  of  necessity,  be  entirely  above  ground,  and  supported 
-on  grillage  in  the  same  manner. 

64*2.  Batteries  are  classified  according  to  their  construction, 
use,  and  armament,  as  follows:  Covered  battery,  intended  for  a 
vertical  fire  and  concealed  from  the  enemy ;  breaching  battery, 
intended  to  breach  the  works  of  the  enemy ;  joint  batteries,  unit- 
ing their  fire  against  the  same  object ;  counter-battery \  one  bat- 
tery opposed  to  another ;  cross-batteries,  forming  a  cross-fire  on 
tan  object ;  oblique  battery  forms  an  angle  of  20  degrees  or  more 
with  the  object  against  which  it  is  directed,  in  contradistinction 
to  direct  battery  ;  raised  battery,  one  whose  terre-plein  is  elevat- 
ed considerably  above  the  ground;  sunken  battery,  where  the 
sole  of  the  embrasure  is  on  a  level  with  the  ground,  and  the 
platform  consequently  sunk  below  it;  enfilading  battery,  when 
the  projectiles  sweep  along  a  line  of  troops,  a  channel,  road,  or 
part  of  a  work ;  horizontal  battery,  when  the  terre-plein  is  that 
of  the  natural  level  of  the  ground ;  open  battery^  without  epaul- 
ment  or  other  covering — wholly  exposed ;  indented  battery,  or  bat- 
tery &  cremailliere^  one  constructed  with  salient  and  reentering 
Angles  for  obtaining  an  oblique  fire  as  well  as  a  direct  fire,  and 
•to  afford  shelter  from  the  eutilade  fire  of  the  enemy;  reverse  bat- 


WIRE    ENTANGLEMENTS,  ETC.  397 

tery,  that  which  fires  upon  the  rear  of  a  work  or  line  of  troops  ; 
ricochet  battery*  that  whose  projectiles,  being  fired  at  low  eleva- 
tion, graze  ancf  bound  along  without  burying  themselves;  masked 
battery,  artificially  concealed  until  required  to  open  upon  the 
enemy ;  mortar  batteries,  gun  batteries,  &c. 

G43.  Mortar  batteries.  These  have  the  principal  features  of 
batteries  for  guns.  It  is  desirable  that  they  should  be  located 
where  good  views  of  the  enemy's  position  may  be  had ;  this,  in 
order  that  the  gunner  may  himself  see  the  effect  of  his  shot,  and 
not,  as  is  too  frequently  the  case,  have  to  depend  upon  the  im- 
perfect report  of  a  distant  observer.  For  siege  mortars,  the 
platforms  are  placed  the  same  distance  apart  as  for  siege  guns, 
viz.,  16  feet ;  for  sea-coast  mortars,  the  distance  is  the  same  as 
for  sea-coast  guns,  viz.,  18  to  22  feet.  They  are  usually  placed 
in  pairs,  with  traverses  between  each  set  of  pairs.  Embrasures 
are  not  required,  and  as  the  platform  must  be  at  such  distance 
from  the  parapet  that  the  blast  will  not  injure  the  interior  crest, 
it  is  not  necessary  to  revet  the  interior  slope,  the  earth  being 
allowed  to  assume  its  natural  slope. 

The  siege-mortar  platform  furnished  for  field  purposes  is  too 
light  to  sustain  much  firing.  For  fixed  batteries,  they  should  be 
constructed  of  heavy  timbers,  and,  to  insure  anything  like  accu- 
racy in  firing,  must  be  both  level  and  stable.  The  sea-coast 
platforms  {par.  229),  when  properly  laid,  are  in  every  respect  effi- 
cient. A  good  kind  of  rail  platform  may  be  made  by  using  two 
pieces  of  timber  (Fig.  4,  Plate  67)  12  to  15  inches  square  and 
9  feet  long  for  the  rails,  to  which  planks  2  or  3  inches  thick  and 
8  or  9  feet  long  are  spiked.  The  rails  are  parallel,  and  have 
their  centres  28  inches  apart  for  the  10-inch  mortar,  and  22  inches 
for  the  8-inch.  A  pit  is  dug  large  enough  to  receive  this  struct- 
ure, and  the  bottom  being  made  perfectly  level,  it  is  placed  in 
it  with  the  planks  down.  Earth  is  filled  in  on  top  of  the  plank- 
ing. This  kind  of  platform  is  particularly  well  adapted  to  sandy 
localities.  If  the  mortar  is  intended  to  be  fired  in  various  direc- 
tions, a  sufficient  number  of  rails  are  used  to  extend  over  the 
whole  surface,  the  planks  being  spiked  to  all  of  them. 

6414*  Wire  entanglements,  abattis,  fyc.  Every  approach 
which  an  enemy  might  use  to  reach  a  work,  should  be  so  ob- 
structed as  to  keep  him  as  long  as  possible  under  a  close  fire  of 
musketry.  The  best  thing  for  this  purpose  is  wire  entangle- 
ment, made  by  planting  stout  stakes,  (Fig.  5,  Plate  67,)  about 
3}  feet  long,  2  feet  in  the  ground  and  7  feet  apart,  in  quincunx 
order  and  in  three  or  four  lines.  Around  the  tops  of  these- 
stakes,  at  from  12  to  18  inches  from  the  ground,  in  notches  pre- 
pared for  the  purpose,  telegraph  or  other  strong  wire  is  securely 


398  TORPEDOES. 

wound,  extending  from  one  stake  to  another.  This  obstacle  is 
rapidly  made,  is  difficult  to  remove,  and  can  be  injured  but  little 
*by  the  fire  of  the  enemy. 

645.  Abattis  is  formed  of  the  large  limbs  of  trees,  or  of  small 
trees  themselves;  the  small  branches  are  chopped  off  and  the 
ends,  pointed  and  interlaced,  are  presented  to  the  enemy.  The 
large  end  of  the  limb  or  tree  is  secured  to  the  ground  b.y  stakes. 
Obstacles  should  be  in  two  or  more  lines,  and  not  too  close  to  the 
-work ;  the  first  line  should  be  about  100  yards  in  front,  and  the 
others  beyond,  at  about  50  yards  intervals. 

646.  Torpedoes,  if  used,  would  be  placed  in  these  intervals. 
These  weapons  depend  for  their  utility  more  upon  their  deter- 
Tiug  than  upon  their  actual  destructive  power.  Men  who  will 
march  bravely  up  through  a  blaze  of  musketry  will  walk  timidly 
overground  in  which  they  suspect  the  hidden  mine.  Torpedoes 
may  be  simply  shells  charged  with  powder  and  slightly  buried 
in  the  ground ;  or  they  may  be  wooden  boxes,  kegs,  or  any  other 
vessel  capable  of  holding  and  keeping  dry  a  charge  of  powder. 
Shells  produce  their  effect  from  their  fragments,  and  likewise, 
if  large,  from  the  blast  of  the  explosion.  Charges  otherwise  in- 
closed produce  effect  only  by  the  blast;  consequently  the  greater 
the  quantity  of  powder  the  greater  will  be  the  effect. 

The  chief  difficulty  in  planting  torpedoes  is  in  the  arrange- 
ment for  igniting  them  at  the  proper  moment.  This  may  be 
done  by  electricity,  as  for  submarine  mines,  or  by  a  self-acting 
♦device  whereby  the  charge  is  exploded  b3r  the  tread  of  an  enemy 
passing  over  it.  The  device  used  by  the  Russians  at  Sebastopol 
is  perhaps  the  best  of  many  that  have  been  tested.  The  case 
consisted  of  a  cubical  wooclen  box  {abed,  Fig.  1,  Plate  68) 
large  enough  to  contain  a  charge  of  10  to  20  pounds  of  powder. 
This  box  was  contained  in  another  box  (ABC  D),  leaving  a  space 
between  of  about  2  inches,  which  was  filled  with  pitch,  render- 
ing the  powder  in  the  inner  box  secure  from  moisture.  The  top 
of  the  exterior  box  was  placed  6  or  8  inches  below  the  surface 
of  the  ground,  and  on  it  rested  a  board  about  the  size  of  the  top ; 
this  board  stood  on  four  legs  of  hoop-iron  about  4  inches  high. 
The  top  of  this  board  was  near  the  surface  of  the  earth,  and 
covered  slightly  so  as  not  to  be  perceived.  On  any  slight  press- 
ure upon  the  board,  such  as  a  man  treading  upon  it,  the  hoop- 
iron  supports  yielded  and  the  board  came  in  contact  with  a  glass 
tube  (X)  containing  sulphuric  acid ;  the  tube  breaking  liberated 
the  acid,  which  came  in  contact  with  a  priming  of  potassa  chlo- 
rate and  loaf-sugar  within  the  box,  causing  instant  combustion 
and,  as  a  consequence,  explosion  of  the  powder.  The  glass  tube 
is  placed  within  another  of  lead,  tin,  or  other  metal  which  bends 


MANTLETS.  899 

readily,  yet  strong  enough  to  afford  a  certain  degree  of  protec- 
tion to  it.  The  metal  tube  conducts  the  acid  to  the  interior  after 
the  glass  is  broken.  Instead  of  the  interior  box,  a  shell  filled 
with  powder  may  be  used.  Other  devices  for  exploding  the 
charge  are  frequently  employed.  They  are  constructed  upon 
the  principle  of  a  plunger  striking  upon  fulminating  composi- 
tion) but  these  are  difficult  to  construct  so  that  moisture  will  not 
enter  and  destroy  either  the  fulminate  or  charge.  When  torpe- 
does are  planted,  the  position  of  each  one  should  be  so  marked 
as  to  be  known  to  friend,  but  not  to  the  enemy.  They  should 
not  be  planted  in  front  of  any  work  from  which  sorties  are  to  be 
made.  They  are  useful  along  beaches  to  prevent  the  enemy 
from  landing. 

64*7.  Mantlets.  A  mantlet  is  a  shield  placed  over  the  mouth 
of  an  embrasure  to  prevent  musketry  bullets  and  fragments  of 
shells  from  flying  through  and  injuring  those  serving  the  piece. 
A  hole  in  the  lower  part  allows  the  muzzle  of  the  piece  to  pass 
through  into  the  embrasure  when  it  is  to  be  fired.  The  size  of 
these  openings  will  depend  upon  the  dimensions  of  the  piece. 
Hope  is  the  best  material  for  constructing  mantlets.  The  usual 
size  of  a  mantlet  is  5  feet  high,  4.5  feet  across,  and  4  inches  thick. 
For  siege  guns  the  opening  is  1.6  feet  high  by  1.3  feet  across. 
Three-inch  rope  is  a  suitable  size ;  it  is  laid  in  three  or  five  thick- 
nesses, each  of  the  two  outer  layers  being  in  one  piece  bent  ver- 
tically. (Fig.  2,  Plate  68.)  The  inner  layers  are  bent  and  laid 
horizontally,  and  the  whole  well  tied  together.  The  mantlet  is 
hung  on  a  horizontal  pole  supported  by  forked  uprights  set  in 
the  ground,  on  each  side  of  the  embrasure,  at  the  foot  of  the 
interior  slope.  The  elasticity  thus  afforded  by  the  supports 
greatly  increases  the  resistance  of  the  mantlet.  A  small  hole  or 
slit  is  pierced  in  the  mantlet  to  allow  the  piece  to  be  aimed. 

Mantlets  of  this  size  weigh  about  400  pounds. 

A  small  ring  mantlet  of  rope  {Fig.  3,  Plate  68)  placed  upon 
the  chase  of  the  gun  is  sometimes  used. 

When  rope  cannot  be  obtained,  one  of  similar  shape  may  be 
made  of  wood. 

Mantlets  may  be  made  of  wood  or  of  iron,  or  of  wood  and 
Iron  combined.  Those  of  the  latter  kind  furnished  for  the  siege 
of  Yorktown  were  made  of  two  thicknesses  of  J-inch  wrought- 
iron  spiked  to  3-inch  oak  plank.  On  the  head  was  a  2-inch 
square  iron  bar  riveted  to  the  edge  of  the  iron  plates,  against 
which  the  oak  planks  abutted.  The  ends  of  this  bar  projected 
6  inches,  and  were  rounded,  serving  as  supports  to  rest  upon 
upright  stakes  or  timbers  standing  against  the  interior  slope  of 
the  parapet. 


400  GUN-SHIELDS — BLOCK-HOUSE. 

Mantlets,  when  supplied  at  ail,  are  supplied  by  the  Engineer 
Department. 

648.  Gun-shields.  When  railroad  iron  can  be  obtained* 
shields,  with  embrasures  in  them,  can  be  made  as  represented  in 
Fig.  1,  Plate  69.  One  thickness  of  iron  is  sufficient  protection 
against  projectiles  from  field  guns,  two  from  siege  guns,  and 
four  from  pieces  of  the  8-inch  rifle  class. 

The  same  material  may  be  used  for  constructing  field  case- 
mates. 

Block-house.  {Fig.  2,  Plate  69.)  This  is  a  species  of  small 
redoubt,  usually  built  of  wood,  and  intended  for  an  isolated 
point  which  can  be  approached  by  stealth  or  stratagem,  requir- 
ing the  garrison  to  be  constantly  on  the  alert,  with  their  arms  in 
hand.  It  is  at  once  a  house  and  a  fort.  They  are  usually  con- 
structed for  the  defense  of  bridges  against  cavalry  raids.  They 
are  also  used  in  the  Indian  country  as  a  defense  against  savages, 
in  which  case  they  are  usually  placed  at  opposite  angles  of  a 
stockade  for  flanking  purposes. 

They  are  made  10  feet  high  in  the  clear,  and  from  20  to  25 
feet  square.  Logs  16  to  18  inches  in  diameter  are  used;  these 
are  hewed  on  two  sides  and  placed  together,  their  hewed  sides 
in  contact.  They  may  be  built  up  in  the  manner  of  a  log-house, 
but  it  is  preferable  to  set  them  up  vertically.  The  roof  is  made 
of  heavy  logs  extending  over  the  walls  about  18  inches  on  all 
sides.  On  these  logs  a  covering  of  earth  is  placed  4  feet  thick  at 
the  crown  and  running  down  to  a  depth  of  6  inches  at  the  eaves. 
This  earth  is  thoroughly  rammed,  and  in  it  are  imbedded  pur- 
lins, upon  which  is  constructed  a  roof  of  boards  or  shingles. 
Loop-holes  for  musketry  are  cut  through  the  walls,  the  splay 
being  on  the  inside,  and  the  height  above  the  floor  8  feet.  A 
banquette  of  plank  3.5  feet  from  the  floor  and  6.5  feet  in  width 
is  carried  around  the  interior ;  this  serves  also  as  a  substitute  for 
bunks. 

Machine  guns  are  eminently  adapted  for  block-houses;  next 
to  these  are  howitzers,  or  other  pieces  effective  with  canister. 
Each  house  should  be  supplied  with  two  or  more  such  pieces, 
embrasures  for  which  are  cut  so  as  to  sweep  the  main  avenues 
of  approach.  The  throats  of  the  embrasures  are  closed  when 
not  in  use  by  heavy  timber  doors,  barred  on  the  inside.  The 
embrasures  are  cut  at  a  proper  height  from  the  floor  for  the  car- 
riage used,  and  the  banquette  made  in  movable  sections  behind 
each  embrasure. 

Around  the  outside  is  dug  a  V-shaped  ditch,  the  earth  being 
thrown  up  against  the  sides  of  the  house,  at  an  angle  of  45  de- 
grees, as  high  as  the  soles  of  the  loop-holes.    The  cheeks  of  the 


BLOCK-HOUSE.  401 

embrasures  through  this  bank  are  of  hewn  timber,  and  a  roof  of 
the  same  is  laid  across  to  sustain  the  slope  just  mentioned.  A 
small  magazine  is  placed  below  the  floor.  A  well-constructed 
abattis  and  wire  entanglement  should  surround  the  work  at  a 
distance  from  it  of  about  100  yards.  A  block-house  thus  con- 
structed is  pretty  secure  against  any  artillery  accompanying 
cavalry  raids. 

The  general  idea  of  a  block-house  may  be  utilized  in  the  con- 
struction of  bomb-proof  covers  or  casemates  for  guns  in  field- 
works. 

26 


£art  (ftigtrtfc. 


ATTACK  AND  DEFENSE  OP  POSITIONS. 

649*  In  the  attack  upon  intrenched  positions,  the  point* 
regarded  as  the  most  advantageous  are  those  in  which  the  gen* 
eral  combination  of  the  defensive  line  forms  a  salient  with  ref- 
erence to  adjacent  parts.  Such  positions  can  receive  but  little 
support  from  collateral  portions,  and  can,  to  a  greater  or  less 
degree,  be  enveloped  by  a  line  of  intrenchments  of  much  greater 
extent  than  itself,  affording  opportunities  for  establishing  enfi- 
lading and  other  batteries,  the  fire  from  which  will  be  conver- 
gent upon  the  point  of  attack. 

Fig.  3,  Plate  69,  illustrates  some  of  the  advantages  to  be  gained 
by  the  selection  of  a  salient  as  the  point  of  attack.  The  full  line 
represents  the  trace  of  a  regular  work  following  theoretically 
the  general  contour  of  the  salient  to  be  attacked.  An  inspection 
of  the  figure  shows  that  A,  upon  the  prolongation  of  the  face 
E  F,  will  be  the  best  possible  position  for  the  attacking  artillery ; 
as  from  this  position  the  projectiles,  after  grazing  the  parapet 
at  the  point  E,  will  rake  the  entire  face  E  F.  It  is  quite  impos- 
sible to  protect  such  a  line  by  traverses  and  at  the  same  time 
maintain  a  stout  defense  against  a  front  attack. 

From  the  point  B,  within  the  prolongation  of  the  face,  the 
latter  is  struck  in  reverse  under  so  small  an  angle  as  to  weaken 
but  slightly  the  advantage  of  enfilade.  It  becomes  less  efficient 
as  its  distance  from  the  prolongation  of  the  face  is  increased. 
The  next  most  advantageous  position  is  at  C,  on  the  other  side 
of  the  prolongation  of  the  face,  striking  its  exterior  direct  but 
under  a  small  angle,  thus  taking  in  flank  the  embrasures  of  the 
face  and  more  readily  destroying  them  without  being  exposed 
to  direct  fire  from  the  face. 

The  locality  sometimes  renders  it  obligatory  to  make  the  artil- 
lery attack  a  direct  one,  as  at  D.  This  is  the  least  advantageous 
of  all. 

The  dotted  line  of  the  figure  represents  more  nearly  actual 
lines  of  field-works.    The  principles,  however,  remain  the  same. 

In  determining  positions  for  batteries,  those  nearest  the  enemy 
are  not  necessarily  the  bes' ;  in  fact,  the  greater  the  range  the 
more  searching  will  be  the  fire.  The  projectiles  will  not  have 
the  same  power  of  penetration  and  destruction  at  long  aa  at 

(403) 


404 


ATTACK   AND   DEFENSE   OF   POSITIONS. 


short  range ;  nevertheless,  for  ordinary  warfare  they  possess  suf- 
ficient of  these  qualities  to  perform  the  work  required  of  artillery 
against  field  lutrenchments. 

650.  The  following  table,  showing  the  drop  of  projectiles  at 
various  ranges,  indicates  the  importance  of  this  factor  in  actual 
warfare.  Fig.  1,  Plate  70,  illustrates  this  graphically,  and,  fur- 
thermore, furnishes  useful  suggestions  as  to  defilading  works  by 
means  of  traverses  and  epaulments.  See  also  table  and  remarks 
in  par.  619. 

Drop  of  projectiles. 


Bangs. 

Rifle- Musket. 

Veloc- 
ity. 

8-Inch 
Rifle. 

IOO-Pdr.  Pakbott. 

Yards. 

Drop. 

Seconds. 

Feet. 

Drop. 

Drop. 

200 

85 

0.5 

1120 

K2© 

400 

50 

1. 

915 

57.3 

600 

30 

1.75 

800 

• • ••• • 

•  ••  •  •  • 

P*2 

700 

25 

•  ••  • 

57.3 

28.6 

>  oolnmns 
f  units  of 
eunit  of 

800 

20 

2.5 

700 

1000 

14 

3.75 

625 

•••••• 

1100 

•  •• 

•  •••• 

19.0 

1200 

•  •• 

558 

28.6 

•••••• 

1400 

••• 

•  ••  • 

14.3 

3  °  o 

1500 

••• 

506 

•••••• 

«a.SS 

1600 

•  •• 

•  ••  • 

19.0 

•••••• 

1700 

•  •• 

11.4 

els 

1900 

•  •• 

•  ••  • 

8.1 

III 

2000 

4 

412 

14.3 

2500 

•  •• 

•  ••• 

11.4 

7.1 

8000 

••• 

8.1 

5.8 

8600 

••• 

. ... 

6.3 

*|2 

4000 

••• 

...  > 

5.1 

4600 

•  •• 

.  ••• 

4.1 

•d  88 

When  the  distance  to  the  object  can  be  determined  and  the 
range  is  such  as  to  require  considerable  elevation,  it  is  by  no 
means  necessary  that  the  object  should  be  seen  from  the  gun, 
provided  range-points  can  be  accurately  established,  as  in  mortar 
firing.  This  is  illustrated  by  Fig.  2,  Plate  70.  In  many  cases 
it  will  be  a  great  advantage  to  locate  guns  in  this  manner,  for 
the  reason  that  the  enemy  will  probably  not  be  able  to  ascertain 
their  position  with  sufficient  accuracy  to  do  them  much  damage. 

Should  the  distance  behind  which  cover  can  be  obtained  be 
quite  short,  as  represented  in  Fig.  3,  Plate  70,  the  charges  for 

§uns  may  be  reduced  so  as  to  allow  the  necessary  elevation  to 
e  given  to  carry  the  projectiles  over  the  cover,  and  at  the  same 
time  drop  them  into  the  enemy's  works.  A  few  trial  shots  will 
enable  the  artillerist  to  accomplish  this  with  certainty.  Siege- 
howitzers  are  used  advantageously  in  this  way. 


ATTACK   AND   DEFEN8E   OF   POSITIONS.  405 

651*  In  nearly  all  ca*es  the  attack  has  the  advantage  over 
the  defense,  in  the  amount  of  fire  that  can  be  brought  to  bear 
upon  any  particular  point.  When  a  position  can  be  completely 
surrounded,  as  is  frequently  the  case  in  sieges,  there  is  no  limit 
to  the  amount  of  fire  that  may  be  brought  to  bear  upon  it,  ex- 
cept the  limit  of  ability  to  obtain  the  requisite  quantity  of  pieces 
and  ammunition.  It  is  therefore  possible  to  throw  into  the  place 
such  a  hail  of  projectiles  as  to  make  it  impossible  for  the  defend- 
ers to  show  any  resistance.  In  most  cases,  however,  the  place 
can  be  but  partly  surrounded ;  nevertheless,  the  great  range  and 
ability  for  concentration  possessed  by  artillery  enable  it  to  ac- 
complish like  results.  It  is  very  certain  that,  under  such  cir- 
cumstances, the  endurance  of  a  place  is  only  a  matter  of  time. 

The  belief  at  present  prevails,  to  a  considerable  extent,  that  It 
is  almost  impossible  to  carry  by  assault  intrenched  positions,  if 
resolutely  defended  by  troops  armed  with  the  breech -loading 
musket.  Such  being  the  case,  the  only  alternative  for  dislodg- 
ing an  enemy  so  situated,  and  who  cannot  be  starved  out,  is  by 
the  use  of  artillery, — a  fact  that  calls  for  the  more  liberal  use  of 
this  arm  and  the  most  skillful  handling  of  it. 

652.  With  sufficient  artillery  an  enemy  can  be  driven,  as 
before  stated,  from  any  position  he  may  occupy.  But  as  there 
is  a  practical  limit  to  the  amount  that  can  be  supplied — and  this 
may  fall  below  what  is  necessary  for  actually  dislodging  him — 
all  that  can  be  expected  of  it  is,  to  so  extinguish  the  fire  of  the 
enemy  as  to  enable  the  infantry  to  gain  possession  of  the  works, 
as  formerly,  by  assault. 

In  preparing  to  make  such  an  attack,  the  first  thing  to  be  done, 
after  determining  the  particular  part  of  the  work  to  be  assaulted, 
is  to  establish  the  batteries  and  ascertain  by  experimental  firing 
how  to  use  them  so  as  to  make  every  shot  tell.  Every  available 
piece  should  be  put  in,  and  other  parts  of  the  line  stripped  tem- 
porarily in  order  to  make  the  assault  certain  of  success. 

653*  The  infantry,  in  the  meanwhile,  has  intrenched  itself 

on  a  line  as  near  as  practicable  to  the  enemy,  and  organizes  into 

three  lines  for  the  assault.     The  artillery  opens  and  keeps  up 

an  incessant  fire.    When  it  is  seen  that  the  enemy  have  been 

driven  to  cover,  the  first  line  of  infantry  advances  as  a  thick  line 

Af  skirmishers  composed  of  detachments,  each  detachment  being 

nder  control  of  its  chief.    If  the  enemy  show  themselves,  this 

ne  opens  fire  and  assists  the  artillery  in  suppressing  them.    The 

len  of  eacli  detachment  keep  together,  and  the  detachments, 

iking  advantage  of  every  accident  of  ground  for  cover,  rush 

►rward  from  point  to  point  as  opportunity  offers.    This  line  is 

)nstantljr  fed   and  strengthened  from  the  next  line  in  rear, 

ich  detachment  sent  forward  gaining  ground  until  the  reverse 


406  ATTACK   AND   DEFENSE    OF   POSITIONS. 

side  of  the  enemy's  work  is  gained ;  seeing  which,  the  second  or 
main  line  rashes  forward,  and  the  whole  clamber  over  the  works- 
and  drive  out  or  capture  the  enemy. 

The  second  or  main  line  is  formed  in  company  columns,  and 
follows  the  first,  or  line  of  skirmishers,  at  a  distance  of  about  500- 
yard  s — less  when  possible.  The  third,  or  reserve,  is  about  'SOO- 
yards  in  rear  of  the  second,  and  is  massed  by  battalions  ready 
to  be  moved  where  required.  The  lines  of  infantry  are  about 
of  equal  strength ;  i.  «.,  each  one-third  of  the  assaulting  force. 

654.  The  artillery  at  first  uses  shell,  but  as  the  infantry  ad- 
vances, and  it  becomes  necessary  to  fire  over  it,  only  solid  pro- 
jectiles will  be  used ;  and  fire  with  these  must  be  discontinued 
when  the  infantry  has  approached  so  as  to  be  in  danger  from  it. 
This  is  the  most  critical  moment ;  but  if  positions  for  the  bat- 
teries have  been  selected  with  skill,  those  on  the  flanks  will  be 
able  to  keep  up  a  cross-fire  until  the  final  rush  is  made.  The 
artillery  commander  must  have  this  matter  so  in  hand  as  to  be 
able  to  commence  or  stop  the  fire  from  any  battery  at  any  mo- 
ment. To  accomplish  this  each  battery  should  be  in  telegraphic 
communication  with  him,  and  he  must  have  a  position  where  he 
will  have  a  clear  view  and  knowledge  of  what  is  going  on  at  the 
point  of  assault. 

As  a  general  rule,  it  is  well  for  the  batteries,  instead  of  sus- 
pending their  fire,  to  increase  the  elevation  so  as  to  throw  their 
projectiles  beyond.  This,  besides  checking  and  disorganizing 
reinforcements  coming  up  to  the  enemy  from  the  rear,  will  have 
a  salutary  moral  effect  upon  him  at  the  point  of  assault. 

When,  as  is  generally  the  case,  the  front  of  the  work  is  pro- 
tected by  abattis  or  other  obstructions,  pioneers  must  accom- 
pany the  first  line  to  clear  ways  for  the  company  columns  of 
the  second  line  to  pass  through. 

The  artillery  commander  will  select  a  proper  number  of  de- 
tachments, placed  under  suitable  officers,  to  advance  with  the 
second  line  for  the  purpose  of  turning  upon  the  enemy  such 
pieces  as  may  be  captured  with  the  works.  These  detachments 
will  carry  with  them  sponges,  rammers,  primers,  and  lanyards. 
Ammunition  will  generally  be  found  with  the  captured  pieces. 

The  most  precise  instructions  are  usually  given  to  division, 
brigade,  and  battalion  commanders  as  to  what  they  are  to  da 
after  getting  possession  of  the  work ;  otherwise  the  troops  take 
no  precautions  against  a  counter-attack.  As  soon  as  practicable, 
the  artillery  commander  moves  batteries  forward  to  establish  a 
new  line  on  the  works  just  captured.  It  is  his  duty  to  take  pos- 
session of  all  captured  artillery  material.  An  accurate  and  com- 
plete inventory  must  be  made  of  it,  together  with  an  account  of 
the  part  it  had  in  the  defense  of  the  place ;  this,  in  order  that 


SIEGES.  407 

there  may  be  no  uncertainty  as  to  the  honors  due  to  various 
parts  of  the  capturing  force. 

Assaults  should  be  made  early  in  the  day,  so  that  the  assault- 
ing force  will  have  time  by  daylight  to  push  and  make  perma- 
nent its  success.  If  night  intervenes,  the  assailed  may  take 
advantage  of  it  to  reorganize  a  new  line  as  strong  as  the  first. 

A  dense  fog  is  most  favorable  for  an  assault,  as  the  assaulting 
force  is  then  able  to  see  plainly  that  which  is  immediately 
around  it,  without  itself  being  seen  by  the  assailed.  For  the 
same  reason,  if  made  at  night,  bright  moonlight  is  favorable. 

It  may  here  be  mentioned  that  artillery  of  batteries  in  posi- 
tion possesses  an  advantage  over  all  other  arms,  in  being  able 
to  be  used  as  well  by  night  as  by  day;  and  this  Is  one  powerful 
element  in  its  favor  when  protracted  operations  are  carried  on 
against  an  enemy  established  in  works. 

If  the  strength  of  the  works  is  such  that  they  cannot  be  car- 
ried in  the  maimer  just  described,  then  recourse  must  be  had  to 
regular  approaches  and  siege  operations. 

Sieges. 

655.  A  place  is  said  to  be  closely  besieged  when  it  is  so  in- 
vested as  to  prevent  those  within  receiving  succor  from  without. 
When  such  an  investment  can  be  effected  and  maintained,  time 
alone  will  effect,  by  starvation,  the  work  of  reduction.  When 
the  operations  against  the  place  are  confined  to  a  simple  inter- 
ruption of  communications,  it  is  termed  a  blockade. 

In  most  cases,  however,  a  place  can  be  but  partly  invested. 
The  besieging  operations  then  consist  in  regular  approaches 
against  particular  parts  of  line  of  the  besieged,  reducing  them 
in  succession  so  as  to  force  him  to  abandon  the  place  which  he 
has  attempted  to  defend. 

No  siege  can  be  successfully  prosecuted  unless  the  resources 
of  the  attacking  army,  especially  in  artillery,  are  superior  to  those 
of  the  besieged. 

656.  Wiien  a  siege  is  to  be  carried  on  by  regular  approaches, 
the  work  so  attacked  should  be  enveloped  as  far  as  possible  by  a 
line  of  batteries  containing  the  heaviest  pieces  within  the  re- 
sources of  the  besieging  party.  These  batteries  are  connected 
by  a  rifle  trench  for  the  accommodation  of  the  infantry  supports, 
and  to  form  a  covered  communication  from  oue  end  of  the  line 
to  another.  It  also  serves  as  a  secure  and  convenient  place  for 
the  accumulation  of  material  for  the  prosecution  of  further  opera- 
tions. The  liue  thus  formed  is  called  the  first  parallel ;  its  dis- 
tauce  from  the  besieged  work  depends,  in  a  great  measure,  on  the 
character  of  the  ground;  if  this  is  undulating  and  broken,  so  as 


408  8IEGES. 

to  form  natural  approaches  to  the  batteries,  the  distance  maybe 
much  less  than  when  the  country  is  level  and  open  to  the  fire  and 
view  of  the  besieged.  As  a  rule,  it  should  be  just  without  the 
zone  of  very  destructive  fire  from  small-arms.  This,  with  the 
present  rifle-musket,  is  about  1500  yards,  a  distance  permitting 
of  the  effective  use  of  the  artillery  mounted  along  the  line.  The 
batteries  containing  guns,  especially  those  of  heavy  calibre, 
should  be  located  on  the  flanks  of  the  line,  leaving  the  interme- 
diate batteries  for  mortars;  this,  for  the  reason  that  guns  so  sit- 
uated will  not  be  masked  and  have  their  fire  checked  by  subse- 
quent operations.  Mortars  can  at  all  times  maintain  their  fire 
over  the  heads  of  troops  occupying  advanced  positions. 

If  the  enemy  occupy  intrenched  positions  in  front  of  the  main 
work  to  be  attacked,  fire  must  be  concentrated  first  upon  one 
and  then  another  of  these  positions  until  he  is  successively  driven 
from  them  into  his  main  work. 

Every  piece  of  artillery  capable  of  throwing  a  projectile  into 
the  works  should  be  brought  into  requisition,,  and  a  superiority 
gained  as  soon  as  possible  over  the  artillery  of  the  besieged. 

65*7.  In  the  meanwhile  preparations  have  been  made,  by  the 
accumulation  of  material,  for  the  establishment  of  a  second  par- 
allel, several  hundred  yards  in  advance  of  the  first.  This  should 
be  done  under  cover  of  night  by  a  line  of  infantry  throwing'  up 
a  rifle  trench.  This  trench  is  enlarged  until  it  forms,  like  the 
first,  a  covered  way  secure  from  the  view  and  fire  of  the  be- 
sieged. Communicatton  with  the  first  parallel  is  secured  by 
means  of  zigzag  trenches,  technically  called  boyaux.  {Fig.  1, 
Plate  71.)  The  branches  of  these  boyaux  are  so  laid  out  that 
the  enemy  will  not  have  an  enfilading  fire  along  them.  Batteries 
are  constructed  along  the  second  parallel ;  the  boyaux  are  en- 
larged to  accommodate  artillery  carriages ;  the  batteries  are  then 
armed.  Gun-shields,  mantlets,  and  all  similar  devices  must  be 
employed  for  the  protection  of  the  guns  and  cannoneers  of  these 
batteries.  The  distance  of  this  line  will  admit  of  the  use  of  the 
smaUer  class  of  mortars,  and  an  abundance  of  them  should  be 
put  in  it.  As  a  rule,  it  is  not  advisable  to  place  in  this  line 
pieces  of  a  heavier  calibre  than  siege  guns;  this,  for  the  reason 
that  heavier  calibres  are  more  difficult  to  serve,  and,  besides,  the 
range  from  the  first  parallel  is  quite  within  the  limits  of  effect- 
ive fire  from  heavy  calibres. 

An  unremitting  lire  is  kept  up  upon  the  besieged  place.  Dar- 
ing the  day  the  guns  will  be  directed  so  as  to  sweep  along  the 
faces  of  the  works,  disabling  the  guns  of  the  enemy  and  demol- 
ishing iiis  traverses,  magazines,  and  bomb-proofs.  During  the 
night  an  incessant  shower  of  mortar  shells  must  be  kept  falling, 
to  prevent  repairs  and  to  keep  the  garrison  constantly  harassed. 


SIEGES.  409 

658.  Using  the  second  parallel  as  a  secondary  base,  the  boy- 
aux  are  pushed  forward  towards  the  salients  of  the  work ;  when 
advanced  to  within  about  half  the  distance  from  the  second  par- 
allel to  the  work,  a  third  parallel  is  constructed  by  running 
trenches  to  the  right  and  left  of  the  heads  of  the  boyaux.  The 
third  parallel  is  for  the  accommodation  of  strong  guards  of  in- 
fantry supporting  the  working  parties,  who,  under  this  protec- 
tion, contrive  to  push  forward  the  boyaux.  They  also  use  their 
fire  to  suppress  musketry  fire  from  the  works  and  to  prevent 
the  enemy  from  serving  his  guns.  An  abundance  of  small  mor- 
tars should  be  placed  in  the  third  parallel  and  vigorously  served. 

As  the  boyaux  are  continued,  it  may  be  found  advisable  to 
establish  a  fourth  parallel. 

Fire  from  adjacent  or  collateral  works  must  be  attended  to,  so 
as  to  prevent  it  from  interfering  with  the  progress  of  the  ap- 
proaches. 

If  the  artillery  of  the  besiegers  is  sufficiently  numerous  and 
powerful,  the  foregoing  arrangements  will  enable  it,  if  vigor- 
ously served,  to  drive  to  cover  the  garrison  of  the  place,  and  to 
so  destroy  the  means  of  defense  as  to  make  further  resistance 
of  little  avail.  The  garrison  will  either  capitulate  or  withdraw ; 
or  if  they  still  hold  out,  an  assault  made  by  infantry  from  the 
advanced  parallels  will  have  a  fair  prospect  of  success.  The 
batteries  having  prepared  the  way  for  assault,  render  assistance 
to  it  by  the  most  spirited  fire.  This  must,  however,  be  directed 
so  as  not  to  interfere  with  the  assaulting  force  as  it  enters  the 
work.  The  practice  which  the  batteries  have  had  up  to  this  time 
will  enable  them  to  direct  their  fire  with  precision,  and  each  one 
must  have  pointed  out  to  it  the  precise  duty  it  has  to  perform. 

Instead  of  an  assault,  sapping  and  mining  may  be  resorted  to, 
and  the  work  made  untenable  bjr  these  means.  These  operations 
are  conducted  by  engineers,  the  functions  of  the  artillery,  mean- 
while, being  confined  to  what  has  heretofore  been  laid  down. 

659*  Masonr3T  revetments  readily  crumble  under  blows  from 
heavy  rifle  projectiles.  The  precision  with  which  the  firing  can 
be  done,  and  the  drop  of  the  projectile  at  long  range,  enable 
the  artillerist  to  reach  scarp  walls  without,  as  in  former  times, 
establishing  batteries  on  the  crest  of  the  glacis.  The  dtbria 
from  the  scarp,  whether  the  latter  be  of  masonry  or  earth,  and 
that  from  the  parapet  resulting  from  constant  hammering,  will 
generally  make  a  ramp  practicable  for  assaulting  parties. 

The  particular  work  to  be  attacked  by  siege  operations  should 
be  selected  with  a  view  to  the  effect  that  its  capture  will  have 
on  other  parts  of  the  line;  in  other  words,  that  its  capture, 
when  accomplished,  will  be  productive  of  decisive  results,  such 
as  leading  to  the  capture  or  abandonment  of  other  works  in  the 


410  SIEGES. 

line,  the  uncovering  of  communications  important  to  the  besieg- 
ed, or  securing  lines  of  approach  to  the  besiegers. 

660.  The  defense  of  works  attacked  by  regular  approaches 
calls  for  the  most  active  and  vigilant  exertions  on  the  part  of  the 
besieged,  especially  so  from  the  artillery.  So  soon  as  the  opera- 
tions of  the  besieger  indicate  what  work  of  a  line,  or  the  par- 
ticular part  of  a  work,  is  his  objective,  every  effort  must  be  made 
to  restrict  the  extent  of  his  lines  of  envelopment.  To  this  end* 
adjacent  and  collateral  works  must  be  armed  with  pieces  of  the 
heaviest  calibre,  so  situated  as  to  take  the  lines  of  approaches  as 
much  as  possible  in  flank.  These  batteries  will  give  special 
attention  to  the  long-range  batteries  of  the  besiegers.  Every 
available  piece  of  artillery  must  be  brought  forward  and  placed 
in  battery  so  as  to  strike  the  besiegers  at  some  point  or  other. 
Unremitted  fire  must  be  maintained  against  the  heads  of  the 
approaches ;  these,  from  their  open  character,  are  peculiarly  vul- 
nerable to  mortar  fire.  As  many  mortars  as  possible  should  be 
placed  in  batteries  established  for  this  special  purpose.  It  Is 
not  advisable  to  crowd  artillery  into  the  objective  point  of  the 
enemy,  but  rather  to  the  right  and  left  of  it ;  this  secures  a  cross- 
fire, and  at  the  same  time  withdraws  the  pieces  from  the  points 
upon  which  the  besieger  concentrates  his  fire. 

If  an  assault  is  to  be  apprehended,  batteries,  especially  of 
machine  guns,  should  be  established  so  as  to  sweep  the  ditch 
and  prevent  the  enemy  from  making  a  lodgment  by  digging 
into  the  scarp  and  parapet.  These  batteries  must  be  well  secured 
by  means  of  bomb-proof  covers  and  gun-shields.  Traverses 
must  be  thrown  up  to  protect  the  guns,  and  bomb  and  splinter 
proofs  constructed  to  shelter  the  cannoneers.  An  interior  line 
of  intrenchments  should  be  constructed  in  rear  of  that  part  of 
the  main  work  attacked.  This  should  be  well  supplied  with 
light  pieces  of  artillery,  which  may  be  kept  under  cover  until 
the  proper  moment  and  then  run  up  to  drive  the  enemy  from 
his  lodgment  on  the  main  work. 

The  supply  of  ammunition  must  be  closely  attended  to,  and 
under  no  circumstances,  where  it  is  possible  to  avoid  it,  should 
it  be  allowed  to  fall  below  the  probable  needs. 

All  of  the  operations  of  the  artillery  in  the  defense,  as  well  as 
in  the  attack,  should  be  directed  by  one  head. 

661.  From  the  foregoing  sketch  it  will  be  perceived  that  the 
operations  of  a  siege  may  be  classed  under  two  heads :  those  which 
are  necessary  to  prevent  the  besieged  from  obtaining  succor,  and 
those  which  are  required  to  gain  possession  of  the  works. 

The  line  established  by  the  besieging  army  to  prevent  succor 
from  without,  is  called  the  line  of  circumvallation ;  that  estab- 
lished for  carrying  on  the  approaches  against  the  work,  is  called 


SIEGES.  411 

the  line  of  countervallation.  Between  these  two  lines  the  besieg- 
ing army  is  established. 

As  a  rule,  the  engineers  have  charge  of  the  planning  and  con- 
strnction  of  the  parallels  and  boyaux ;  the  artillery,  of  locating, 
constructing,  arming,  and  serving  the  batteries.  All  of  these 
operations  are  minutely  connected  with  each  other,  and  pro- 
ceed together.  It  is,  therefore,  the  duty  of  officers  having  them 
in  charge  to  act  in  accord  in  carrying  them  out. 

662.  No  specific  rules  can  be  laid  down  regarding  the  amount 
of  artillery  required  for  siege  operations. 

The  most  remarkable  sieges  that  have  taken  place  since  the 
introduction  of  the  present  style  of  artillery  and  small-arms  have 
employed  about  6500  lighting  men  per  mile  of  investment,  with 
5  pieces  per  thousand  men,  or  33  per  mile. 

The  conditions  of  each  particular  case  must  govern  as  to  the 
kind  and  calibre  of  pieces  and  the  number  of  each,  together 
witli  the  quantity  of  ammunition  necessary.  As  a  general  rule, 
a  large  proportion  of  the  pieces  should  be  of  heavy  calibre.  In 
some  cases  the  means  of  transportation  will  admit  of  none 
heavier  than  can  be  carried  on  traveling  carriages.  When  rail- 
roads are  available  still  heavier  classes  maybe  brought  up,  while 
with  water  transportation  there  is  no  limit. 

The  object  of  the  siege  must  likewise  be  considered.  If  it  is 
intended  to  simply  cut  the  place  off  from  supplies  and  reduce  it 
by  starvation,  an  intrenched  line  of  battle  armed  with  ordinary 
field  artillery  will  be  sufficient.  If  the  place  besieged  is  a  town 
or  city  to  be  reduced  by  bombardment,  loug  range  and  heavy 
calibres  are  most  desirable;  the  same  class  would  also  be  re- 
quired for  a  work  approachable  only  on  one  side,  to  be  destroyed 
by  battering.  When  a  work  of  this  nature  is  to  be  reduced  by 
regular  approaches,  there  will  be  required,  in  addition  to  guns 
and  mortars  of  heavy  calibres  for  long  range,  a  large  proportion 
of  regular  siege  artillery  capable  of  being  readily  moved  up  as 
the  works  of  the  besiegers  approach  the  enemy. 

The  amount  of  ammunition  required  will  depend  upon  the  char- 
acter of  the  work  to  be  done  and  the  duration  of  the  siege.  If  the 
source  of  supply  is  certain  and  regular,  the  quantity  to  commence 
with  may  be  small  compared  with  what  should  be  provided  un- 
der other  conditions.  Considering  the  source  of  supply  reason- 
ably certain,  about  200  rounds  per  piece  for  sea-coast  and  100O 
rounds  per  piece  for  other  classes  will  be  a  fair  allowance. 

663.  When  a  siege  is  determined  upon,  the  chief  engineer 
and  artillery  officers  must  study  every  condition  of  the  particu- 
lar case  and  decide  upon  what  seems  to  be  the  best  for  carrying; 
out  the  general  plan.  Nothing  must  be  omitted  to  make  the 
preparation  complete. 


412  SIEGES. 

In  commencing  siege  operations,  the  first  thing  necessary  is 
to  gain  possession  of  a  large  area  of  ground  as  near  as  possible 
to  the  place  to  be  besieged,  for  the  purpose  of  establishing 
depots,  artillery  parks,  hospitals,  and  camps.  This  area  must 
be  made  entirely  secure  by  intrenchments,  after  the  manner  of 
4iii  intrenched  camp. 

Depots,  parks,  camps,  &c,  should  be  screened  as  much  as 
possible  from  the  view  of  the  enemy,  and  a  thorough  system  of 
roads  and  telegraphic  communication  established  between  them 
and  with  the  batteries  on  the  line.  When  practicable  a  railroad 
should  be  laid,  forming  a  main  artery  from  one  end  of  the  line 
to  the  other.  Wharves  are  constructed  for  the  unloading  of 
vessels,  and  depots  established  convenient  thereto.  These  will 
•consist  of  buildings  for  the  accommodation  of  engineer  and  quar- 
termaster's stores  and  subsistence  supplies,  together  with  work- 
shops for  repairs. 

The  water  supply  must  be  carefully  looked  after,  not  only  as 
to  quantity,  but  as  to  purity.  This  is  demanded  upon  sanitary 
grounds.  All  springs,  wells,  and  running  brooks  should  be 
guarded  so  that  they  may  not  be  fouled  by  the  watering  of 
animals  or  by  bathing  and  washing  of  clothes.  Reservoirs 
should  be  constructed  to  prevent  loss  of  water  at  night. 

In  localities  where  the  supply  is  not  convenient,  water-carts 
should  be  used  for  bringing  it  to  where  it  is  required  for  use. 
This  prevents  straggling  and  idling. 

The  site  for  the  artillery  park  and  depot  should  be  easily 
accessible  from  all  parts  of  the  line.  Magazines  for  powder  and 
fixed  ammunition  must  be  constructed  in  the  safest  places.  Ar- 
tillery carriages  will  be  parked  systematically  in  such  manner  as 
to  allow  of  any  being  withdrawn  when  required.  The  artillery 
transportation  trains,  parked  in  the  same  manner,  consist  of  a 
number  of  wagons  sufficient  to  carry  supplies  to  the  artillery  depot 
■and  to  keep  the  batteries  along  the  line  supplied  with  ammunition. 

Materials  required  in  the  construction  of  batteries,  such  as 
gabions,  fascines,  mantlets,  and  sand-bags,  together  with  those 
for  platforms  and  magazines,  are  usually  supplied  from  the 
engineer  depot. 

664.  The  character  of  the  artillery  employed  in  a  siege  will 
determine  the  nature  of  the  machines,  implements,  and  stores 
required.  Supposing  that  the  heavier  as  well  as  the  lighter  cali- 
bres can  be  used,  a  fair  allowance  for  each  100  pieces,  large  and 
small,  would  be  as  follows :  Six  traveling  forges,  with  stores  as 
per  par.  258;  six  batter y-wa<jo us ■,  with  stores  as  per  par.  258; 
Sve  sling-carts  (large),  ten  sllng-carts  (hand),  twenty  hand-carts, 
five  truck-wagons  (heavy),  ten  mortar-wagons,  one  hundred  hand- 
barrows,  two  hundred  paulins,  ten  garrison  gins  with  tackle 


SIEGES.  413 

complete,  five  siege  gins  with  tackle  complete,  five  30-ton  hy- 
draulic-jacks, five  15-ton  hydraulic-jacks,  two  gun-lifts,  five  cra- 
dles with  rollers,  two  hundred  and  fifty  way-planks,  and  five  seta 
of  blocks,  skids,  Ac,  as  specified  in  par.  534. 

Each  piece  of  artillery  is  furnished  with  the  implements  and 
equipments  heretofore  specified  in  connection  with  its  service 
and  mechanical  manoeuvres. 

Each  service  magazine  will  be  supplied  with  a  set  of  appro- 
priate scales,  measures,  funnels,  <fcc,  and  each  battery  with  a 
field-glass  and  set  of  signal  flags. 

One  or  more  officers  will  be  detailed  to  ascertain  the  distance* 
from  the  various  batteries  to  the  objects  to  be  fired  at,  and  will 
be  furnished  with  the  necessary  instruments  for  the  purpose. 

Each  artillery  officer  will  provide  himself  with  a  pocket  com- 
pass, a  pair  of  dividers,  a  protractor  scale,  and  pencils ;  also- 
paper  for  notes  and  field-sketching.  The  instruments  are  con- 
veniently carried  in  a  shoulder-pouch,  as  represented  in  Fig.  2, 
Plate  71. 

Intrenching  tools  are  furnished  from  the  eugineer  depot. 

665.  The  preparations  for  the  siege  having  sufficiently  pro- 
gressed, and  the  engineers  having  laid  out  the  lines  of  intrench- 
ments,  the  artillery  commander  will  select  sites  for  the  batteries, 
determine  their  armament,  and  designate  the  troops  to  con- 
struct, arm,  and  serve  them. 

The  teams  of  the  light  batteries  are  used  for  transporting 
artillery  from  the  landing-place  to  the  park,  and  thence  to  the 
batteries  on  the  line  of  investment. 

Important  works  along  the  line  are  named,  open  batteries  are 
numbered  in  regular  order,  and  the  whole  line  and  system  of 
communications  mapped,  so  that  there  may  be  no  confusion  in 
distributing  material  and  supplies. 

666.  When  the  siege  is  fully  opened,  the  question  of  supply- 
ing the  batteries  with  ammunition  is  by  no  means  a  small  one, 
and  requires  thorough  systematizing  to  prevent  an  undue  accu- 
mulation at  some  points  and  deficiency  at  others. 

The  allowance  of  ammunition  for  the  immediate  use  of  each 
piece  varies  to  suit  circumstances ;  those  batteries  in  most  prom- 
inent positions  have  the  greatest  supply,  100  rounds  being  about 
the  maximum  and  50  the  minimum.  The  number  of  rounds  per 
piece  diminishes  as  the  calibre  increases.  The  supply  is  main- 
tained by  means  of  a  train  of  wagons  kept  specially  for  the  pur- 
pose. 

In  order  that  the  daily  expenditure  may  be  known  at  the 
depot,  the  commanding  officer  of  each  battery  on  the  line  will 
each  morning  make  out  and  forward  to  the  depot  a  report  of 
the  following  form : 


414 


REPORT   OF   BATTERY. 


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410 


REPORT    OF    FIRING. 


The  officer  in  charge  of  the  iim munition  at  the  depot  loads  hU 
wagons  with  the  amount  required,  and  gives  to  each  teamster  a 
ticket  stating  the  contents  of  his  wagon  and  to  which  battery  it 
is  to  go. 

The  train,  under  competent  wagon-masters,  starts  out  before 
night-fall  and  proceeds  so  as  to  reach  the  batteries  after  dark. 
Guides  from  the  several  batteries  meet  the  train  at  appointed 
places  and  direct  the  particular  wagons  to  the  proper  batteries. 
Upon  the  arrival  of  the  wagons,  an  officer  of  the  battery  gives 
nis  personal  supervision  to  the  unloading,  and  signs  the  ticket 
brought  by  each  driver,  noting  any  discrepancy.  The  ticket  is 
returned  by  the  driver  to  the  officer  at  the  depot. 

All  articles  that  have  become  unserviceable  or  are  useless  in 
the  battery,  together  with  all  empty  packing-boxes  and  barrels, 
an;  relumed  by  the  wagons  to  the  depot,  a  list  of  them  being 
sent  kick  with  the  teamster. 

To  simplify  accountability,  the  officer  at  the  depot  will  be 
responsible  for  all  the  artillery,  ammunition,  and  material. 
Battery  commanders  give  him  memorandum  receipts,  and  are 
held  accountable  for  any  loss.  The  ammunition  fired  is  ex- 
pended by  the  depot  officer  upon  the  reports  made  by  the  officers: 
commanding  the  several  batteries. 

As  a  general  rule,  cartridges  will  be  made  up  at  the  depot,  and 
sent  to  the  batteries  either  in  budge-barrels  or  in  chests  of  con- 
venient size  made  for  the  purpose. 

The  latter  part  of  the  report  on  the  foregoing  form  is  for  the 
Information  of  the  commandant  of  artillery,  and  for  the  purpose 
of  keeping  a  complete  history  of  the  artillery  firing.  From  the 
daily  reports  a  monthly  abstract  is  made  for  each  piece  upon 
the  following  form  ; 

Monthly  report  of  artillery  firing,  tiegt  of. ,  May  18... 


Kl!TO  OF 


No.  and  calibre  1 


it  it 

1 1 lis  S 


DEFILES.  417 

The  command  of  the  entire  artillery  is  vested  in  an  officer  of 
that  arm  of  service,  who,  besides  other  necessary  qualifications, 
should  have  rank  commensurate  with  the  importance  of  his 
position. 

The  line  of  works  is  divided  into  sections,  each  of  a  size  capa- 
ble of  close  supervision  by  the  officer  assigned  to  the  command 
of  it. 

Defiles. 

667.  A  defile,  in  a  military  sense,  is  any  narrow  place  the 
passage  of  which  can  be  made  by  troops  only  when  undeployed. 

Mountain  passes,  river  crossings,  narrow  isthmuses,  and  roads 
through  close  forests  represent  the  usual  forms  of  defiles.  They 
necessarily  imply  obstacles  in  the  way  to  the  free  movement  of 
armies,  and  are  therefore  important  features  in  a  theatre  of  war, 
and  consequently  points  demanding  special  attention  bjr  way  of 
defensive  arrangements.  For  these  no  precise  rules  can  be  laid 
down ;  nevertheless  some  general  principles  may  be  stated. 

The  chief  advantage  offered  by  a  defile  is,  that  with  but  com- 
paratively slight  intrenchments  a  small  force  is  able  to  hold  a 
position  against  a  much  greater;  this,  for  the  reason  that,  owing 
to  the  essential  nature  of  a  defile,  the  attacking  force  must  oper- 
ate in  a  constrained  position,  not  admitting  of  much  develop- 
ment of  fire.  The  main  object,  therefore,  is  to  secure  such  a 
column  of  fire  over  the  defile  as  to  make  it  impossible  for  the 
enemy  to  stem  it ;  this  is  best  accomplished  by  selecting  such 
points  as  will  give  an  enfilade  fire.  They  should  be  selected 
with  a  view  to  mutual  support,  and  intrenched  in  such  manner 
as  to  be  secure  against  capture  by  coup  de  main.  The  enemy 
must  be  compelled  to  make  his  attacks  with  divided  forces  and 
inferior  numbers.  This  is  best  accomplished  by  occupying  sev- 
eral positions  within  flanking  distance  of  each  other.  He  will, 
probably,  not  be  able  to  attack  all  simultaneously,  and  it  will  be 
a  costly  operation  for  him  to  attack  them  in  detail. 

The  positions  should  be  so  chosen  as  to  allow  them  to  con- 
centrate their  artillery  fire  upon  any  point  where  it  might  be 
advantageous  for  the  enemy  to  establish  batteries,  and  the  artil- 
lery of  the  defense  should  be  of  such  power  as  to  preclude  all 
possibility  of  his  doing  so.  All  hollow  approaches,  such  as 
would  be  formed  by  ravines  in  a  mountain  pass,  must  be  search- 
ed by  the  fire  of  artillery.  This,  as  a  rule,  will  require  pieces  to 
be  placed  in  open  batteries  exterior  to  the  inclosed  works.  Such 
batteries  must-  be  well  supported  by  infantiy  sheltered  in  rifle 
trenches.    The  whole  system  should  be  so  connected  as  to  leave 

27 


418  DEFILES. 

no  part  isolated  or  without  the  support  of  other  parts,  and  the 
defense  of  each  point  must  be  stubborn  in  the  extreme  to  pre- 
vent the  enemy  from  gaining  possession  of  advantageous  posi- 
tions. 

All  parts  of  the  line  or  group  of  works  must  be  In  communi- 
cation by  telegraph,  telephone,  or  signaling,  or  by  all  three. 
This  is  a  matter  of  the  greatest  moment  in  secuiing  not  only 
the  physical,  but  also  the  moral  support  of  the  parts. 

In  every  case  artillery  should  form  a  chief  feature  in  the 
means  of  defense ;  the  kind  of  pieces  for  the  different  parts  of 
the  system  will  depend  upon  the  character  of  the  ground  and 
of  the  nature  of  the  attacks  that  may  be  expected.  As  a  rule, 
all  approaches  must  be  covered  by  fire;  wherever  horizontal 
fire  cannot  be  made  to  reach,  mortars  must  be  used.  However 
much  the  pieces  may  be  scattered,  they  must  be  capable  of  con- 
centrating their  fire  upon  any  position  the  enemy  may  assume. 

As  defensive  works  in  defiles  are  required  to  be  self-sustaining, 
frequently  for  long  periods,  the  supply  of  ammunition  must  be 
ample  for  all  probable  wants. 

If  a  defile  is  to  be  held  for  the  purposes  of  an  army  either 
advancing  or  retiring  in  front  of  an  enemy,  the  head  of  it  to- 
wards the  enemy  must  be  secured  by  a  line  similar  to  a  Ute-dc- 
pont;  this,  for  the  purpose,  if  advancing,  of  giving  room  for  the 
army  to  deploy  after  passing  the  defile,  and  to  prevent  the  en- 
emy from  stinking  it  while  defenseless  in  column ;  if  retreating, 
the  same  disposition  is  necessary  to  hold  the  pursuing  army  in 
check  while  the  troops  are  defiling  to  the  rear.  In  both  cases, 
as  the  object  is  to  keep  the  enemy  from  closing  in  for  a  pitched 
battle,  artillery  must  be  freely  used. 

In  the  attack  upon  a  defile,  intrenched,  armed,  and  defended 
as  it  should  be,  artillery  will  be  the  most  important  weapon ; 
this,  for  the  reason  that,  from  the  very  nature  of  defiles,  other 
arms  can  act  but  feebly,  while  artillery  possesses  the  power  of 
reaching  its  object  beyond  intermediate  obstacles.  As  much 
artillery  should  be  brought  to  act  as  possible,  and,  although  it 
may  be  widely  dispersed,  its  fire  must  be  concentrated  upon 
some  particular  work  in  the  system  of  defenses.  The  work  must 
be  attacked  with  such  vigor  and  persistency  as  to  insure  its 
destruction  and  easy  capture.  Other  works,  successively,  are 
attacked  in  the  same  manner. 

The  operations  upon  both  sides  thus  partake  of  the  nature  of 
a  siege,  and  are  governed  by  the  same  principles. 


RIVERS.  419 

El  VERS. 

668.  Rivers  traversing  the  theatre  of  war  occupied  by  hostile 
armies  have  a  marked  influence  on  the  operations  of  each. 
Whenever  they  are  to  be  crossed  in  the  presence  of  an  enemy, 
either  in  advancing  or  retiring,  the  use  of  artillery  and  of  field- 
works  becomes  of  great  importance ;  this,  for  the  reason  that  the 
operation  of  crossing  necessarily  consumes  considerable  time, 
during  which  the  army  is  divided — astraddle,  as  it  were,  the 
stream — and  requires  the  aid  of  that  arm  which,  from  a  fixed 
position,  possesses  the  power  of  covering  at  long  range  the 
movements  of  other  troops. 

The  place  of  crossing,  whether  bridge,  ferry,  or  ford,  is  sim- 
ply a  defile  through  which  the  army  has  to  pass,  and  which  must 
be  completely  covered  from  the  fire  of  the  enemy,  who  must  not 
be  permitted  to  establish  batteries  within  range  of  the  crossing. 
This  is  best  effected  by  covering  every  point  accessible  to  him 
with  the  fire  of  artillery. 

A  river  in  front  of  an  army  operating  on  the  defensive,  stands 
to  it,  somewhat,  as  a  wet  ditch  does  to  a  fortification,  and  should 
be  so  guarded  as  to  make  the  crossing  of  it  a  difficult,  if  not  a 
hazardous,  operation  to  an  advancing  enemy.  Points  at  which 
the  communications  of  a  country  converge  are  those  most  ad- 
vantageous for  an  enemy  to  select  for  crossing.  These  should 
be  secured  by  strong  inclosed  works,  armed  with  artillery  of 
such  power  as  to  cause  him  to  make  a  long  detour  and  to  adopt 
a  less  advantageous  point. 

If  the  stream  is  navigable,  such  works  form  a  place  of  refuge 
for  the  craft  that  ply  on  it,  and  which,  falling  into  the  hands 
of  the  enemy,  would  furnish  him  with  means  of  crossing  and 
assist  him  in  carrying  on  his  operations. 

The  size  of  the*  work  will,  to  a  great  degree,  depend  upon  the 
force  that  can  be  detached  from  the  main  body  for  garrisoning 
it ;  but,  generally,  a  well-constructed  work  containing  a  thousand 
men,  adequately  supplied  with  artillery,  will  prove  a  formidable 
obstacle  to  the  crossing  army.  Points  thus  established  should 
not  be  so  numerous  as  to  cripple  the  efficiency  of  the  defending 
army  bjr  dispersion.  They  should  be  rather  in  the  nature  of 
bases  for  temporary  points  of  observation  along  the  river,  secure 
against  capture  by  coup  de  main,  and  threatening  to  the  llanks 
and  rear  of  the  crossing  army. 

T4te-de-poni.  A  bridge  is  protected  by  a  ISte-de-pont,  the 
nature  and  extent  of  which  will  depend  upon  the  character  of 
the  attacks  to  be  expected.  Against  mere  raiding  parties,  & 
redan  or  lunette — as  represented  in  Fig.  1,  Plate  72— is  sufficient. 


420  RIVERS. 

Two  or  three  pieces  of  artillery  may  be  put  itf  it,  but  it  is  prefer- 
able to  locate  batteries,  as  at  B  and  C,  on  the  opposite  side  of 
the  river,  to  flank  the  redan  and  cross  their  fire  in  front  of  it. 

Against  a  large  force  well  supplied  with  artillery,  a  line  of 
works  (a  b)  must  be  thrown  up  and  well  armed  with  artillery, 
for  the  purpose  of  keeping  him  beyond  artillery  range  from  the 
bridge.  Batteries  of  heavy  pieces  are  placed,  as  at  c  dy  to  flank 
the  line. 

The  operation  of  crossing  a  river  by  an  army  in  presence  of  a 
vigilant  enemy,  is  one  of  great  delicacy,  as  it  necessarily  con- 
sumes considerable  time,  during  which  it  is  more  or  less  divided 
and  subject  to  every  disadvantage.  Judicious  use  of  artillery 
is  of  the  first  importance.  The  first  thing  to  be  done  is  to 
gain  a  footing,  on  the  opposite  side.  This  is  usually  accom- 
plished by  stratagem  or  by  surprise.  Before  a  large  opposing 
force  can  arrive,  batteries  must  be  established  on  the  side  from 
which  the  crossing  is  made  to  cover  with  their  fire  a  large  area 
of  ground  opposite.  Every  available  piece  must  be  put  in,  and 
the  enemy  kept  back  until  bridges  can  be  laid  and  a  strong 
line  of  infantry  passed  over  and  intrenched.  Siege  guns,  owing 
to  their  great  range  and  power,  are  the  best  adapted  for  this 
service.  The  batteries  should  be  extended  up  and  down  the 
stream  for  three  or  more  miles  on  each  side  of  the  crossing-place ; 
this,  for  the  purpose  of  enfilading  the  flanks  of  the  enemy  and 
preventing  him  from  bringing  his  artillery  to  bear  upon  the  cross- 
ing. The  place  for  crossing  should  be  selected,  as  far  as  practi- 
cable, with  a  view  to  advantageous  positions  for  batteries.  The 
convex  side  of  a  curve  (Fig.  2,  Plate  72)  with  hills  dominating 
the  opposite  side  gives  every  advantage.  This  secures  a  cross- 
fire upon  the  opposite  peninsula,  under  cover  of  which  the  in- 
fantry line  and  light  field  batteries  can  be  thrown  forward  to  a 
distance  of  two  or  three  thousand  yards  and  established  in  an 
intrenched  line  as  represented  in  the  figure. 

If  the  enemy  has  gun-boats  on  the  river,  especially  if  they  are 
iron-clads,  provision  against  them  must  be  made  by  laying  across 
the  channel  liues  of  submarine  mines,  with  heavy  batteries  es- 
tablished for  their  protection.  These  batteries  must  be  strongly 
intrenched. 

The  operation  of  crossing  a  river  by  an  army  pressed  in  rear 
by  another,  is  the  reverse  of  that  just  described. 

When  practicable,  the  concave  side  of  a  bend  is  selected,  across 
which  a  line  of  temporary  intrenchments  is  constructed ;  bat- 
teries are  established  on  the  opposite  side,  and  the  army  with- 
drawn under  protection  of  their  fire.  The  batteries  should  cover 
themselves  with  gun-pits,  and  give  special  attention  to  such 


DEMOLITION.  i21 

artillery  as  the  enemy  may  bring  forward  for  the  purpose  of 
reaching  the  place  of  crossing. 

Demolition. 

669.  Buildings.  In  military  operations  it  sometimes  becomes 
necessary  to  destroy  buildings,  bridges,  Ac.  Wooden  structures 
are  readily  and  effectually  destroyed  by  burning.  Ordinary 
dwelling-houses  of  stone  or  brick  may  be  blown  down  by  placing 
against  the  walls  charges  of  from  25  to  50  pounds  of  powder,  each 
contained  in  a  bag,  box,  or  any  convenient  vessel,  and  exploded 
by  means  of  an  electric  primer,  a  slow-burning  time-fuse,  or  a 
piece  of  slow  match.  The  effect  of  the  explosion  is  to  blow 
away  a  portion  of  the  foot  of  the  wall,  that  above  settling  down 
without,  as  a  rule,  toppling  over.  An  inside  angle  or  corner  of 
the  building  is  the  most  advantageous  place  for  the  charge,  for 
the  reason  that,  being  confined  on  two  sides,  the  explosive  force 
acts  more  powerfully  than  when  against  a  plain  surface,  and 
also  because  the  angle  or  corner  of  the  building,  being  a  point  of 
greatest  support,  when  blown  away  leaves  the  remaining  parts 
greatly  weakened. 

Against  strong  and  massive  walls,  such  as  are  generally  found 
in  large  public  edifices,  charges  of  powder,  unless  very  heavy, 
have  but  little  effect  when  simply  exploded  against  the  wall 
without  tamping.  Inside  angles  should,  if  possible,  be  taken,  or 
when  the  building  has  buttresses,  the  angles  formed  by  them  are 
advantageous  for  confining  the  explosive  force  and  causing  it  to 
take  effect  on  the  wall.  The  powder  is  placed  in  a  box  or  keg 
and  covered  with  earth  and  stones.  When  placed  five  or  six 
feet  above  the  foot  of  the  wall  the  effect  is  greatly  increased. 

In  all  cases  where  demolition  is  to  be  produced,  dynamite  may 
be  used  instead  of  gunpowder.  Its  destructive  effect  is  about 
thirty  times  that  of  powder,  weight  for  weight. 

Bridges.  To  destroy  the  arches  of  a  masonry  bridge,  exca- 
vate a  hole  down  to  the  crown  or  haunch  of  the  arch,  place  in  it 
a  charge  of  one  or  two  hundred  pounds  of  powder,  according  to 
the  thickness  of  the  arch,  tamp  it  well  with  earth  and  stones,  and 
explode  it. 

The  amount  of  powder  is  determined  from  the  formula  X=»J 
A  *  X  B :  in  which  X  is  the  charge  in  pounds,  A  the  line  of  least 
resistance  through  the  arch,  and  B  the  breadth  of  the  bridge, 
both  in  feet. 

When  the  width  of  the  arch  is  over  25  feet,  two  charges  should 
be  placed,  to  prevent  the  chance  of  blowing  a  hole  through  the 


422  DEMOLITION. 

middle  without  bringing  down  the  sides.  These  should  be 
exploded  simultaneously,  if  possible. 

When  the  side  walls  are  lightly  built,  it  is  better  to  pull  enough 
of  the  stone  away  to  allow  a  tunnel  being  run  on  top  of  the 
arch  to  the  middle  of  the  roadway.  This  does  not  interfere  with 
the  use  of  the  bridge  during  the  operation,  and  if  it  is  not  de- 
sired to  destroy  the  bridge  immediately,  the  charge  may  be  kept 
in  its  place  ready  for  use  at  any  moment.  In  this  case  the  charge 
should  be  in  a  tight  box  or  barrel,  well  pitched  to  protect  it 
against  moisture. 

The  charge  may  be  exploded  by  means  of  an  electric  primer, 
the  ordinary  fuse  used  in  blasting,  or  with  a  powder  hose.  This 
latter  is  made  of  canvas  or  any  stuff  that  will  hold  fine-grained 
powder,  and  is  inclosed  in  a  trough  to  protect  it  from  the  moist- 
ure of  the  earth. 

The  ordinary  blasting  fuse  is  known  in  this  country  under 
the  name  of  the  safety  fuse  and  Toy's  fuse ;  in  England,  as 
Bickford's  fuse. 

It  consists  essentially  of  a  column  of  fine-grained  gunpowder 
inclosed  in  flax,  hemp,  or  cotton,  and  made  up  with  different 
coverings,  according  to  the  use  to  which  it  is  applied.  When 
intended  for  immediate  use  on  light  work  in  dry  sand,  it  is 
unprotected  by  additional  coverings;  when  intended  for  use  in 
wet  ground  or  under  water,  it  is  covered  with  varnished  tape  or 
gutta-percha. 

These  fuses  are  somewhat  uncertain  in  their  rate  of  burning, 
but  average  about  one  yard  in  a  minute. 

The  ordinary  varieties  must  be  kept  in  a  cool,  dry  place,  and 
preserved  from  contact  with  oil. 

Wooden  bridges  are  easily  burnt ;  but  if  great  secrecy  is  neces- 
sary, a  hole  may  be  bored  with  an  auger  in  a  main-brace  and  a 
charge  of  powder  or  dynamite  exploded  therein,  blowing  it  to 
pieces.  Charges  should  be  placed  in  several  of  the  braces  and 
exploded  as  near  simultaneously  as  possible. 

During  the  war  of  the  rebellion  a  small  torpedo  was  devised 
for  this  purpose.  It  consisted  of  a  tin  cylinder  1.75  inch  in  di- 
ameter and  about  7  inches  long.  Both  ends  of  the  cylinder  were 
open,  and  through  it  passed  a  bolt  of  0.75-inch  iron,  with  a  stout 
head  at  one  end  and  a  nut  at  the  other,  each  having  a  diameter 
of  2  inches.  A  washer  of  the  same  size  as  the  head  was  placed 
under  the  nut;  through  a  hole  in  the  washer  passed  a  strand 
of  slow  match  to  communicate  fire  to  the  powder  with  which 
the  cylinder  was  filled.  A  coat  of  varnish  protected  the  powder 
from  moisture.    To  use  it,  a  hole  2  inches  in  diameter  was  bored 


DEMOLITION.  423 

in  the  timber;  into  this  the  torpedo  was  driven,  head  down- 
wards, and  the  fuse  ignited. 
I  The  most  effectual  way  of  destroying  an  iron  bridge  is  to  at- 

tack the  abutments  by  mining  down  so  as  to  get  behind  the 
!  masonry  a  large  charge  of  powder  or  dynamite,  which  being 
exploded,  destroys  the  supports  of  the  superstructure.  When 
1  time  and  means  permit,  remove  as  many  bolts  as  possible,  so  as 
J  to  weaken  the  parts,  after  which  build  a  strong  fire  and  beat  the 
!  main-braces  to  make  the  bridge  sag  and  warp  out  of  shape,  or  to 
come  down  entirely. 

Canals.  These  may  be  temporarily  disabled  by  cutting  em- 
bankments. The  most  effectual  way,  however,  is  to  blow  up  a 
lock,  which  may  be  done  by  digging  down  behind  a  facing  wall 
and  placing  against  it  a  charge  of  two  or  three  hundred  pounds 
of  powder  or  a  few  pounds  of  dynamite,  tamping  well  aud  ex- 
ploding it.  A  lock  destroyed  in  this  manner  requires  a  long 
time  to  repair.  The  arches  of  an  aqueduct  may  be  broken  by 
drilling  holes  and  blasting. 

An  arm}'  depending  upon  a  railroad  for  its  supplies  should  be 
provided  with  an  organized  construction  corps,  fully  equipped 
with  every  means  for  making  speedy  repairs.  Damages  done  to 
railroads  are  easily  repaired,  in  comparison  with  those  done  to 

CftOftlft. 


gart  putt. 


SUBMARINE  MINES. 

6 TO.  The  term  torpedo,  when  used  in  a  military  sense,  desig- 
nates those  contrivances  for  producing  explosions  calculated  to 
act  destructively  against  an  enemy  coming  into  their  immediate 
vicinity. 

They  are  chiefly  used  for  obstructing  rivers  and  entrances  to 
harbors,  and  are  either  stationary  or  capable  of  movement. 
When  stationary  they  are  called  submarine  mines,  leaving  the 
term  torpedo  for  all  offensive  and  movable  combinations  of  this 
nature.  The  use  and  application  of  the  latter  fall  more  partic- 
ularly to  the  province  of  the  Navy,  the  former  to  the  Army,  and, 
being  employed  as  auxiliary  to  shore  batteries,  constitute  a 
branch  of  service  naturally  belonging  to  or  intimately  connected 
with  the  artillery  arm. 

Submarine  mines  are  applicable  to  almost  any  situation  liable 
to  be  attacked  by  ships,  but  in  every  instance  they  should  be  so 
arranged  as  to  be  covered  by  the  guns  of  forts  or  detached  bat- 
teries, so  that,  while  acting  as  outworks  of  these  latter,  they  will 
be  protected  from  destruction  by  boats  from  a  hostile  fleet. 

The  comparatively  small  cost  of  this  species  of  defense  allows 
of  its  extensive  use  as  an  agent  to  deter  an  enemy  from  approach- 
ing a  fortified  position,  and  to  cause  him  to  begin  the  tedious  and 
dangerous  operation  of  clearing  the  channel,  or  to  land  and  at- 
tempt to  capture  the  place  without  the  aid  of  his  ships.  This  in 
most  cases  would  enable  the  defenders  to  hold  out  until  the  arri- 
val of  a  relieving  force. 

The  materials  required  for  most  submarine  mines  are  articles 
of  commerce  easily  procurable,  or  capable  of  being  kept  on  hand 
without  damage  or  loss,  and  a  system  of  defense  by  such  means 
can  be  carried  on  by  a  comparatively  small  number  of  men. 

671.  Submarine  mines  may  be  briefly  described  as  charges 
of  gunpowder,  or  other  explosive  agents,  inclosed  in  water-tight 
cases  of  iron  or  other  material,  and  placed  under  water  at  such 
depths  that,  by  their  explosion,  they  may  sink  or  seriously  dam- 
age a  vessel  passing  in  their  vicinity.  They  are  classed  under 
two  heads,  viz.:  Mechanical,  those  which  depend  for  the  explo- 
sion of  the  charge  on  mechanical  means,  such  as  the  simple  per- 

(425) 


426  SUBMARINE   MINES. 

cussion  of  a  vessel  coming  in  contact  with  them ;  and  Electrical, 
those  which  are  fired  by  electrical  agency,  either  by  the  vessel 
closing  the  circuit,  or  at  will  from  the  shore. 

The  former  class,  or  mechanical  mines,  are  capable  only  of 
very  limited  use.    When  once  placed  in  a  channel  they  make  it 
equally  impassable  to  friend  and  foe.    They  are,  therefore,  only 
applicable  to  certain  cases ;  as,  for  example,  when  it  becomes 
necessary  to  block  up  a  channel  completely,  that  is  to  say,  to 
render  it  altogether  impassable  till  the  mines  have  been  removed. 
They  might,  however,  be  employed  on  a  flat  beach,  dry  at  low 
water,  to  cover  the  flanks  of  electrical  mines  defending  the  navi- 
gable channel.    In  such  case  they  could  be  planted  or  removed 
at  low  water  with  comparative  security.    The  number  of  elec- 
trical cables,  &c,  required  would  be  reduced  by  such  an  arrange- 
ment.    Mechanical  mines  are  not  applicable  to  harbors  of  refuge, 
in  which  merchant  ships  might  run  to  avoid  an  enemy. 

It  would,  furthermore,  be  absolutely  necessary  to  make  some 
arrangement  by  which  they  could  be  exploded  at  will,  as  the 
most  effectual  way  of  getting  rid  of  them  when  it  became  neces- 
sary to  clear  the  channel,  as  the  process  of  removal  in  the  ordi- 
nary way,  by  boats,  would  be  far  too  dangerous  an  operation  to 
undertake.  On  the  order  hand,  submarine  mines  of  this  descrip- 
tion possess  the  advantage  of  capability  of  being  kept  in  store 
and  ready  for  use  at  short  notice ;  they  require  no  knowledge  of 
electricity  in  their  management,  and  they  might  be  used  with 
advantage  in  certain  cases  where  electrical  submarine  mines  are 
not  obtainable. 

The  second  class  of  submarine  mines,  those  to  be  fired  by  elec- 
trical agency,  admit  of  a  very  much  larger  field  for  their  employ- 
ment. They  may  be  fired  either  at  will  by  an  observer,  who, 
judging  of  the  position  of  the  vessel,  closes  the  circuit,  so  that  the 
charge  may  be  exploded  at  the  right  moment ;  or  the  vessel  her- 
self may  be  made  to  complete  the  circuit,  causing  a  current  to 
pass  and  fire  the  charge. 

The  disadvantages  of  electrical  submarine  mines,  as  compared 
with  those  fired  mechanically,  are  the  multiplicity  of  wires  re- 
quired and  the  necessity  of  having  a  certain  number  of  espe- 
cially trained  men.  This  number,  however,  is  comparatively 
small. 

The  advantages  of  electrical  mines  are,  that  they  are  always 
absolutely  under  the  control  of  the  observer  in  charge  of  them. 
By  simply  detaching  the  battery  used  in  firing  them  they  become 
perfectly  harmless,  and  friendly  vessels  may  pass  over  them  with 
safety,  which  is  not  the  case  with  those  arranged  for  mechanical 
ignition.    Again,  they  can  be  rendered  active  at  a  moment's 


POSITION   OF   SUBMARINE   MINES.  427 

notice  by  reconnecting  the  battery.  By  means  of  electrical  con- 
trivances, arrangements  are  so  effected  that  vessels  passing  over 
mines  give  notice  of  their  presence  without  exploding  the  mine. 
In  this  respect  electrical  submarine  mines  are  a  great  safeguard 
against  attack  by  surprise,  and  against  vessels  passing  at  night, 
or  in  a  fog.  Nor  can  they  be  tampered  with  by  an  enemy  with- 
out its  being  immediately  known,  and  exactly  what  mine.  In 
the  electrical  system,  when  a  mine  is  exploded,  or  becomes  inef- 
fective from  any  cause,  another  can  be  laid  down  in  its  place, 
without  danger,  by  simply  making  the  neighboring  mines  in- 
active for  the  time  being.  Another  important  advantage  of 
this  system  is  the  power  of  testing  electrically,  without  going 
near  it,  the  condition  of  each  separate  charge  at  any  time  after 
submersion,  and  of  ascertaining,  with  almost  absolute  certainty, 
whether  it  can  be  fired  or  not.  None  of  these  advantages  apper- 
tain to  mines  of  the  mechanical  system. 

€»72.  Position  of  submarine  mines.  The  following  general 
rules  govern  in  selecting  sites  for  these  mines : 

1st.  Thejr  may  be  used  in  combination  with  floating  obstruc- 
tions, as  booms,  or  with  grounded  obstructions,  as  sunken  ves- 
sels, piles,  &c,  or  without  them. 

2d.  They  should  be  placed  in  such  positions  that  their  explo- 
sions will  not  injure  any  passive  obstructions  combined  with 
them,  or  destroy  the  electric  cables  of  adjoining  mines. 

3d.  At  least  two,  and,  where  practicable,  more,  rows  of  mines 
should  be  arranged  across  the  channel  to  be  defended. 

In  deep  water,  it  is  more  necessary  to  employ  several  lines  of 
mines  than  in  shallow,  because  in  the  latter  ease  a  vessel  sunk 
by  a  mine  would  herself  offer  an  impediment  to  others  follow- 
ing ;  but  in  deep  water  the  explosion  of  a  mine  leaves  a  gap, 
through  which  there  is  a  safe  passage. 

4th.  Submarine  miues  should  be  placed  in  the  channels  through 
which  large  vessels  only  can  pass;  the  shallower  places  being,  m 
all  cases  where  such  a  course  is  practicable,  rendered  impassable 
by  passive  obstructions  resting  on  the  bottom. 

5th.  Submarine  mines  should  be  placed  in  the  narrowest  part 
of  a  channel.  The  advantages  of  such  a  position  are  evident,  as 
a  smaller  number  will  answer  the  purpose. 

6th.  When  the  depth  of  the  water  and  other  circumstances 
admit  of  it,  a  submarine  mine  should  always  rest  on  the  bottom. 
Under  such  circumstances,  all  complications  originating  in  moor- 
ing arrangements  are  avoided ;  its  position  is  more  easily  de- 
lined,  and  it  is  not  so  easily  displaced  by  accident,  or  discoverecfr 
and  destroyed  by  an  enemy. 

7th.  No  indication  of  their  position  should  be  allowed  to  appear 


428  ARRANGEMENT   OF   SYSTEM. 

■on  the  surface  of  the  water.  Under  certain  conditions  it  may  be 
impracticable  to  conceal  them  altogether;  as,  for  example,  where 
there  is  a  large  rise  and  fall  of  tide.  Under  such  circumstances, 
the  smallest  possible  indication  of  their  position  must  be  allowed. 

8th.  When,  from  the  depth  of  the  water,  the  charges  cannot  be 
placed  on  the  bottom,  they  should  be  so  moored  as  to  float  from 
15  to  40  feet  below  the  surface.  In  places  where  there  is  a  con- 
siderable rise  and  fall  of  tide,  special  arrangements  would  be 
necessary  for  this. 

9th.  The  place  in  which  batteries  and  instruments  connected 
with  the  ignition  of  electrical  submarine  mines  are  arranged, 
should  be  in  those  portions  of  the  defensive  works  which  are 
likely  to  be  held  longest,  so  that  a  command  may  be  kept  over 
the  mines  to  the  latest  possible  moment  in  the  defense. 

10th.  Great  care  should  be  taken  to  lay  the  electric  cables  in 
such  positions  as  to  render  their  discovery  by  an  enemy  as  diffi- 
cult as  possible,  and  likewise  to  secure  them  against  every  acci- 
dent. 

11th.  The  position  of  the  mines  should  be  well  covered  by  the 
fire  of  the  guns  of  the  forts  or  shore  batteries  of  the  place  to  be 
defended,  to  prevent  their  destruction  by  boats. 

12th.  Submarine  mines  should  not  be  thrown  away  by  firing 
them  at  small  boats,  except  under  very  exceptional  circum- 
stances, but  should  be  reserved  for  larger  vessels. 

6*73.  Arrangement  of  system.  The  object  to  be  obtained  in 
arranging  any  system  of  mines  for  the  defense  of  a  channel,  is 
to  place  them  in  such  a  position  that  a  vessel  passing  along  that 
•channel  must,  at  some  one  moment,  whatever  course  she  may 
take,  come  within  the  radius  of  destructive  effect  of  one  of  the 
mines.  This  would  be  attained  by  placing  the  mines  in  a  sin- 
gle row  across  the  channel,  so  that  their  circles  of  destructive 
■effect  may  at  least  touch  each  other.  To  this  simple  arrange- 
ment there  are,  however,  practical  difficulties ;  among  which  is 
'  the  danger  of  entanglement  between  the  mooring  cables  of  adja- 
cent mines,  or  their  electric  cables,  especially  when  there  is  an 
ebb  and  flow  of  the  tide.  When  mines  are  very  close  together, 
it  is  impossible,  with  the  most  perfect  mooring  arrangements,  to 
prevent  entanglements  of  this  nature,  particularly  when  laying 
down  the  mines  and  arranging  the  gear  in  connection  therewith. 

The  difficulty  of  grappling  for  and  raising  a  mine  for  exami- 
nation is  greatly  increased  by  this  very  close  approximation. 
Again,  when  mines  are  very  close  to  each  other  the  explosion  of 
-one  is  very  likely  to  injure  its  neighbor;  or,  where  an  electrical 
system  is  adopted,  to  disturb  the  particular  mechanism  of  the 
system.    It  becomes  necessary,  therefore,  to  allow  some  lati- 


ARRANGEMENT   OF   STSTEM.  42  !> 

tude,  in  order  to  obviate  these  difficulties  and  at  the  same  time 
to  preserve  the  theoretical  precision  and  closeness  of  a  single  line. 
This  is  effected  by  placing  the  mines  in  two  or  more  lines,  at  a 
distance  from  each  other  something  greater  than  the  radii  of 
destructive  effect  of  the  mines.  Fig.  3,  Plate  72,  explains  this 
method. 

In  this  figure,  a  b  represent  the  theoretical  line  required  to 
close  the  channel,  and  it  is  only  necessary  to  move  back  every 
second  mine  to  the  line  c  d,  and  every  third  mine  to  the  line  e  /, 
to  secure  the  object  required.  A  fourth  line  (g  A),  or  even  a 
fifth  (i  k),  may  be  added  with  advantage,  taking  care  that  these 
last  shall  cover  the  intervals  left  between  those  in  advance  of 
them  in  such  a  way  that  a  vessel  passing  obliquely  through  the 
intervals  of  the  first  three  lines  may  come  in  contact  with  a  mine 
in  the  fourth  or  fifth.  This  arrangement  overcomes  the  great 
objection  that  attaches  to  a  single  line,  which,  in  case  a  breach 
is  once  effected,  affords  a  safe  passage  until  repaired.  It  like- 
wise makes  it  more  difficult  for  an  enemy  to  discover  the  limits 
to  the  area  of  danger,  and  consequently  weakens  the  efforts  of 
the  enemy  by  the  moral  effect  of  uncertainty. 

The  arrangement  in  lines  is  the  best,  both  for  facility  in  lay- 
ing the  mines  so  as  to  space  the  area  with  certainty,  and  for 
finding  their  positions  when  it  becomes  necessary  to  raise  them 
for  examination.  It  also  affords  facility  in  determining  what 
particular  mine  it  is  necessary  to  explode  to  strike  a  vessel 
attempting  the  passage. 

So  much  depends  upon  local  circumstances — such  as  the  nat- 
ure of  the  channel  or  roadstead  to  be  defended,  the  probable 
means  of  attack  at  the  disposal  of  an  enemy,  the  draught  of 
water  of  the  vessels  of  a  hostile  fleet,  &c. — that  a  great  deal 
must  be  left  to  the  officer  commanding  the  defense. 

The  size,  strength,  and  character  of  the  vessels  to  be  guarded 
against  will  determine  the  power  of  the  mines  to  be  used,  and 
this,  again,  will  decide  the  distance  between  the  lines  and  the 
intervals  thereon  of  the  mines. 

6*74.  Neither  experiments  nor  observations  in  actual  warfare 
have  yet  determined,  except  approximately,  the  size  of  charges 
necessary  to  perform  the  work  required  of  mines  under  the  vari- 
ous circumstances  that  would  arise  in  service.  The  stronger  the 
vessel  the  greater,  manifestly,  will  be  the  charge  required  to 
destroy  it.  As  a  general  rule,  the  strength  of  vessels  increases 
with  their  size,  as  likewise  does  their  draught ;  therefore  a  mine 
of  sufficient  power  to  destroy  a  large  vessel  will  evidently  de- 
stroy a  smaller  one,  and  this  notwithstanding  the  charge  be 


430  EXPLOSIVES. 

placed  at  a  depth  suitable  for  the  larger  vessel  and  of  the  con- 
sequent intervening  cushion  of  water. 

The  depth  of  water  in  a  channel  decides  very  closely  the  char- 
acter of  vessels  that  can  pass;  this,  for  war  vessels,  may  be 
placed  at.  15  feet  for  the  minimum.  Furthermore,  it  has  been 
decided  that  a  charge  of  2000  pounds  of  gunpowder,  if  properly 
placed,  is  sufficient  to  destroy  the  largest  vessel.  This,  there- 
fore, is  laid  down  as  the  maximum  charge  to  be  used  in  any  one 
mine.  A  rule  for  approximately  determining  the  charge  for 
-depths  of  water  from  15  to  40  feet  is,  that  the  square  of  the 
<lepth  in  feet  gives  the  quantity  in  pounds  of  gunpowder  re- 
quired. Gunpowder  being  the  most  common  and  best  known  of 
the  explosives,  is  taken  as  the  standard.  So  far  as  known,  the 
explosive  effect  of  gun-cotton,  when  used  for  submarine  mines, 
is  about  four  times,  and  that  of  dynamite  about  ten  times  that 
of  gunpowder,  weight  for  weight.  The  character  of  the  bottom 
on  which  submarine  mines  are  planted  has  considerable  effect 
on  their  destructive  power,  a  yielding,  muddy  bottom  being 
much  less  favorable  than  a  hard  and  resisting  one.  In  the  fore- 
going rule,  about  ten  per  cent,  should  be  added  to  the  charges 
when  the  bottom  is  soft,  or  when  the  mines  do  not  rest  on  the 
bottom.  It  is  evident  that  the  nearer  the  lines  of  mines  arc 
to  each  other  the  less  will  be  the  chances  of  a  vessel  passing 
through  safely;  they  should,  however,  be  so  far  apart  as  to  ena- 
ble the  electric  cables  connected  with  them  to  be  laid  in  a  safe 
position  when  carrying  them  to  the  electrical-room  from  which 
the  system  is  to  be  worked.  The  distance  likewise  should  be 
sufficiently  great  to  enable  the  observers,  taking  cross-bearings, 
to  determine  with  certainty  when  a  vessel  is  over  anj'  particular 
line.  These  conditions  will,  as  a  rule,  give  100  yards  as  a  mini- 
mum and  200  jTards  as  a  maximum. 

The  distance  apart  at  which  two  mines  on  the  same  line  may 
T)e  placed  so  that  the  explosion  of  one  will  not  injure  the  other, 
depends  upon  the  size  of  the  charges  employed.  For  the  maxi- 
mum charge — 2000  pounds — this  interval  should  not  be  less  than 
200  feet;  for  charges  not  exceeding  500  pounds  the  interval 
may  be  reduced  to  100  feet.  This  necessary  interval  between 
the  charges  in  a  line  is  one  reason  which  renders  the  employ- 
ment of  two  or  more  lines  of  mines  essential  to  a  proper  main- 
tenance of  the  defense.  It  also  sufficiently  explains  the  object 
to  be  attained  in  placing  them  in  such  a  way  that  the  charge  in 
the  second  line  shall  cover  the  intervals  in  the  first,  and  those 
an  the  third  shall  cover  the  intervals  in  the  second,  and  so  on. 

675.   Explosives,    The  explosives  used  for  submarine  mines 


DYNAMITE — NITRO-GLYCERINE.  431 

are  confined  almost  exclusively  to  gunpowder,  dynamite,  and 
gun-cotton. 

Gunpowder  lias  already  been  discussed  in  Part  First,  pars, 
180  et  seq. 

Dynamite.  This  explosive  compound  is  merely  a  preparation 
in  which  nitro-glycerine  is  itself  presented  lor  use,  its  explosive 
properties  being  those  of  the  nitro-glycerine  contained  in  it,  as 
the  absorbent  is  an  inert  body.  Dynamite  is  formed  of  75  parts 
of  nitro-glycerine  absorbed  by  25  parts  of  "  kieselguhr,"  a  porous 
siliceous  earth. 

In  appearance  dynamite  is  a  loose,  soft,  readily-moulded  sub- 
stance, of  a  buff  color.  It  is  prepared  by  simply  mixing,  with  a 
wooden  spatula,  the  nitro-glycerine  with  finely-powdered  kiesel- 
guhr in  a  leaden  vessel.  It  freezes  at  39°— 40°  F.,  and  when 
solidly  frozen  cannot  be  exploded ;  but  if  in  a  pulverized  state, 
it  can  be  exploded,  though  with  diminished  violence.  It  is  eas- 
ily thawed  by  placing  the  vessel  containing  it  in  hot  water. 

Friction  or  moderate  percussion  does  not  explode  it.  Its  fir- 
ing 'point  is  356°  F.  If  flame  be  applied  to  it,  it  burns  with  a 
strong  flame.  It  is  fired  by  means  of  fulminate  of  mercury,  and 
its  explosive  force  is  about  seven  times  that  of  gunpowder. 

This  explosive  compound  is  now  most  extensively  used  for 
general  blasting  purposes  all  over  the  world,  especially  for  sub- 
marine work,  where,  for  removing  rocks,  it  is  exploded  by  sim- 
ply placing  it  on  the  surface  of  the  rock,  the  water  forming  the 
tamping. 

For  ground  and  buoyant  mines,  where  actual  contact  between 
the  hostile  vessel  and  the  torpedo  will  be  rarely  achieved,  this 
being,  next  to  nitro-glycerine,  the  most  violent  of  all  known  ex- 
plosive agents,  and  being  cheaply  and  readily  procured,  is  the 
very  best  explosive  for  such  torpedoes. 

Dualine.  This  is  prepared  by  mixing  nitro-glycerine  with 
sawdust  and  saltpetre.  It  possesses  the  principal  qualities  of 
dynamite,  though  inferior  to  it. 

Lithofracture.  This  is  prepared  by  mixing  nitro-glycerine, 
kieselguhr,  charcoal,  soda,  saltpetre,  and  sulphur.  It  likewise 
is  inferior  to  dynamite. 

Nitro-glycerine.  This  is  an  explosive  compound  formed  by 
the  action  of  nitric  acid  upon  glycerine  at  a  low  temperature. 
At  ordinary  temperature  it  is  an  oily  liquid,  having  a  specific 
gravity  of  i.6.  Freshly  made,  it  is  creamy  white  and  opaque, 
but  clears  and  becomes  colorless  on  standing  for  a  certain  time, 
depending  on  the  temperature. 

It  does  not  mix  with,  nor  is  it  affected  by,  water.    It  has  a 


432  GUN-COTTON. 

sweet  aromatic  taste,  and  produces  violent  headache  when  placed 
on  the  tongue. 

The  opaque,  freshly-made  nitro-glycerine  does  not  freeze  un- 
til the  temperature  is  lowered  to  3° — 5°  below  zero  F.,  but  when 
cleared  it  freezes  at  39° — 40°  P.  It  freezes  to  a  white  crystalline 
mass,  and  in  this  state  it  can  be  thawed  by  placing  the  vessel 
containing  it  in  water  at  a  temperature  not  over  100°  F. 

If  flame  is  applied  to  freely-exposed  nitro-glycerine,  it  burns 
slowly  without  explosion.  When  in  a  state  of  decomposition  it 
is  very  sensitive,  exploding  violently  when  struck,  even  when 
unconfined.  When  pure  it  is  not  sensitive  to  friction  or  mode- 
rate percussion.  If  struck  with  a  hammer,  only  the  particles 
receiving  the  blow  explode,  the  remainder  being  scattered. 

The  firing  point  of  nitro-glycerine  is  about  365°  F.,  though 
it  begins  to  decompose  at  a  lower  temperature.  The  mode  of 
firing  it  usually  employed  is  by  means  of  a  f  ulminate-of-mercnry 
detonating  fuse.  In  a  frozen  state  it  cannot  be  fired  even  by 
large  charges  of  fulminate. 

It  is  kept  in  tight  tin  cans  of  40  to  50  pounds  each,  and  should 
not  be  transported  or  handled  except  when  in  the  frozen  state. 

It  is  the  most  violent  of  all  known  explosive  agents,  its  force 
being  about  ten  times  that  of  gunpowder. 

Gun-cotton.  This  is  formed  by  the  action  of  concentrated 
nitric  acid  and  raw  cotton.  When  thus  acted  on  the  cotton  is 
little  changed  in  appearance,  though  more  brittle  and  slightly 
harsher  to  the  touch. 

If  a  flame  be  applied  to  it  in  a  loose,  dry  state,  it  flashes  up 
without  explosion ;  if  compressed,  it  burns  rapidly,  but  quietly. 
Moist  compressed  gun-cotton  under  the  same  circumstances 
burns  slowly. 

In  the  compressed  state  in  which  it  comes  from  the  hydraulic- 
press  it  contains  about  15  per  cent,  of  water;  in  this  condition 
it  may  be  cut,  sawed,  bored,  or  perforated  with  a  red-hot  iron 
with  perfect  safety.  If  placed  on  a  fire,  a  feeble  transparent 
flame  flickers  over  the  surface  from  time  to  Jime  as  the  exterior 
becomes  sufficiently  dry  to  inflame ;  in  this  way  it  burns  away 
very  gradually. 

This  comparative  safety  of  wet  gun-cotton,  cduplcd  with  the 
fact  that  its  detonation  in  that  state  may  be  readily  accomplished 
through  the  agency  of  a  small  quantity  of  dry  gun-cotton  termed 
a  primer^  which,  by  means  of  a  fulminating  fuse  or  detonator, 
is  made  to  act  as  the  initiative  detonating  agent,  gives  it  impor- 
tant advantages  over  other  violent  explosive  agents,  when  used 
for  purposes  which  involve  the  employment  of  a  considerable 


FULMINATE   OF   MERCURY — CASE.  438 

quantity  of  the  material,  on  account  of  the  safety  attending  its 
storage  and  necessary  manipulation. 

Gun-cotton  is  not  sensitive  to  friction  or  percussion.  Its  firing 
point  is  about  360°  F.  It  is  insoluble  in  and  unaffected  by  water. 
When  not  in  water  it  is  liable  to  spontaneous  decomposition, 
which,  under  favorable  conditions,  may  result  in  explosions. 

Compressed  gun-cotton  is  free  from  such  danger,  as  it  may  be 
kept  and  used  saturated  with  water.  It  is  stored  in  the  wet  state, 
care  being  taken  that  it  is  not  exposed  to  a  temperature  that  will 
freeze  the  water  in  the  cakes,  as  this  would  disintegrate  the  cakes 
by  the  expansion  of  the  water  in  freezing. 

Compared  with  dynamite,  it  is  not  so  violent,  and  occupies 
more  space,  weight  for  weight,  and  also  requires  a  more  compli- 
cated means  of  detonating  it.  On  the  other  hand,  gun-cotton  is 
infinitely  safer  to  store  and  manipulate,  and  is  not  so  subject  to 
detonation  by  concussion  as  dynamite. 

The  explosive  effect  of  dynamite  and  gun-cotton  is  a  rending 
or  a  shattering  one,  while  that  of  gunpowder  is  an  uplifting  or 
heaving  one,  and  always  in  the  line  of  least  resistance — differ- 
ing in  this  respect  from  the  first  two  substances,  in  which  the 
explosive  effect  is  nearty  equal  in  every  direction.  This  prop- 
erty of  dynamite  and  gun-cotton  makes  them  most  suitable  for 
demolitions.    (See  Demolition,  par.  669.) 

Gun-cotton,  while  in  the  pulpy  state,  is  pressed  into  cylinders 
of  about  3  inches  in  length  by  2.5  inches  in  diameter.  For  trans- 
portation these  cylinders  are  placed  in  boxes,  each  containing 
about  three  dozen  ;  the  box  is  filled  with  water,  which,  after  re- 
maining a  few  minutes,  is  drained  off  and  the  box  closed. 

Fulminate  of  mercury.  This  is  the  composition  used  in  the 
detonating  primers  employed  for  the  ignition  of  dynamite  and 
gun-cotton.  It  is  the  substance  in  percussion  caps  that  detonates 
and  produces  fire  when  the  cap  is  struck  a  sharp  blow. 

Dry  fulminate  of  mercury  explodes  violently  when  heated  to 
367°  F.,  by  the  electric  spark,  or  when  struck.  When  wet  it  is 
inexplosive,  and  therefore  it  is  always  kept  wet,  being  dried  in 
small  amounts  when  required  for  use.  Great  care  is  requisite 
in  handling  it. 

For  the  purpose  of  detonating  nitro-glycerine  or  its  prepara- 
tions, 15  grains  of  the  fulminate  are  sufficient,  but  to  detonate 
gun-cotton  25  grains  are  necessary.  The  fulminate  in  detonat- 
ing fuses  should  be  inclosed  in  a  copper  case  or  cap,  and  must 
never  be  loose.  The  fulminate  should  be  wet  when  charging 
the  detonators,  and  afterwards  dried. 

676.   Case.    Whatever  may  be  the  form  and  construction  of 

28 


434  case. 

the  case  which  contains  the  charge  of  a  submarine  mine,  the 
following  conditions  are  essential : 

1st.  It  must  be  water-tight,  to  prevent  damage  to  the  charge 
by  leakage. 

2d.  It  must  be  sufficiently  strong  to  bear  handling  without 
danger  of  becoming  leaky  by  straining,  and  must  be  able  to  sus- 
tain the  external  pressure  due  to  the  depth  of  water  at  which  it 
is  to  be  placed. 

3d.  When  gunpowder,  or  gun-cotton  fired  with  an  ordinary 
fuse,  is  used,  it  must  be  sufficiently  strong  to  hold  the  charge 
together,  as  it  were,  for  an  instant  at  the  moment  of  ignition,  so 
that  its  full  effect  may  be  obtained  bjr  as  thorough  a  combustion 
as  possible  of  the  charge. 

4th.  In  the  case  of  a  buoyant  mine,  it  must  be  capable  of  being 
arranged  with  a  large  excess  of  flotation,  so  that  when  moored  it 
may  remain  as  stationary  as  possible  at  the  required  point. 

5th.  It  should  be  of  such  form  as  to  be  capable  of  being  han- 
dled and  moored  conveniently. 

6th.  It  should  be  of  such  form  as  to  secure  the  thorough  igni- 
tion of  the  charge  with  the  smallest  possible  number  of  fuses. 

7th.  It  should  be  easy  of  construction,  and  not  too  costly. 

First,  witli  reference  to  the  form  of  the  case.  This  generally 
is  either  conical,  spherical,  or  cylindrical.  The  former  is  the 
best  for  self-acting  buoyant  mines.  The  apex  (a,  Fig.  1,  Plate 
73)  of  the  cone  forms  a  convenient  point  to  which  the  mooring 
cable  may  be  attached,  while  the  base,  terminating  by  a  curved 
portion  (6),  serves  as  an  air-chamber,  giving  the  necessary  buoy- 
ancy to  keep  the  mooring  cables  taut  and  to  hold  the  mine  in  a 
comparative^7  stationary  position  in  a  current  or  tide-way.  The 
nipples  (c  c)  containing  the  fulminating  composition  are  placed 
on  the  rim  uniting  the  base  with  the  conical  surface.  In  this 
position  they  are  most  likely  to  be  struck  by  a  passing  vessel. 
There  should  be  four  or  more  of  these  nipples,  depending  upon 
the  size  of  the  case. 

For  all  other  cases,  except  the  one  just  mentioned  of  a  float- 
ing mine,  intended  for  small  charges  to  be  exploded  by  mechan- 
ical means,  the  cylindrical  form  is  best,  and  the  one  most  fre- 
quently adopted  for  both  ground  and  buoyant  mines  containing 
heavy  charges.  Fig.  2,  Plate  73,  represents  the  form  so  suc- 
cessfully used  by  the  Confederates,  1861-65 ;  Fig.  3  represents 
that  of  the  Austrians ;  Fig.  4  that  of  the  English  for  small  buoy- 
ant mines,  in  which  J  is  a  wooden  jacket,  giving  buoj'ancy  and 
protection  to  the  case ;  C  is  the  circuit-closer. 

For  large  ground  mines,  the  best  form  of  case  seems  to  be 
that  of  the  turtle  mine,  represented  in  Fig.  5.    A  heavy  charge 


MOORING.  485 

may  be  contained  in  it ;  it  forms  its  own  anchor,  and  it  would 
withstand  an  explosion  of  an  adjacent  mine  without  sustaining1 
any  injury.    This  is  the  best  form  for  resisting  strong  currents. 

The  difficulty  and  cost  of  making  spherical  cases  have  hereto- 
fore debarred  their  adoption  on  a  large  scale,  but  recently  Gen- 
eral Abbott,  U.  S.  Engineers,  has  simplified  the  process  of  man- 
ufacture and  made  them  .practicable.  This  process  consists  in 
pressing  circular  disl$s  of  steel  into  hemispherical  segments, 
which  are  united  by  flanges,  as  represented  in  Fig.  6. 

As  regards  the  material  of  which  the  cases  may  be  most  advan- 
tageously constructed,  several  substances  have  been  tried  and 
used ;  such  as  wood,  iron,  and  vulcanized  India  rubber.  For 
actual  war  service,  regularly -constructed  torpedoes  or  mines 
would  generally  be  turned  over  to  the  posts  ready  for  use ;  but 
it  might  become  necessary  to  improvise  cases  out  of  such  mate- 
rials as  would  be  available.  Tight  barrels  and  hogsheads,  when 
-properly  strengthened,  are  a  good  substitute  for  even  the  most 
improved  form  of  case.  The  barrel  or  cask  is  simply  an  exter- 
nal shield  for  the  protection  of  the  charge,  which  is  contained 
in  a  water-tight  envelope,  and  may  be  an  India-rubber  bag  or 
a  tin  or  zinc  can.  The  strengthening  of  the  cask  is  to  guard 
against  collapsing  when  submerged  in  deep  water.  Under  ordi- 
nary circumstances  the  depth  of  the  water  will  not  be  so  great 
as  to  require  strengthening  of  good  casks  beyond  stout  hoops 
of  iron.  As  the  charge  must  generally  remain  a  considerable 
time — perhaps  many  months — under  water  before  explosion,  it 
is  most  essential  to  have  the  case,  whatever  it  maybe,  completely 
water-tight ;  and  with  this  view  the  cask  is  coated,  both  inside 
and  outside,  with  a  composition  of  pitch  and  tar.  The  envelope 
■containing  the  charge  within  the  cask  should  be  firmly  fixed,  so 
that  no  independent  motion  may  disturb  the  connections  of  the 
•electrical  apparatus. 

6YY.  Mooring.  This  is  the  most  difficult  operation  connected 
with  submarine  mines.  It  is  a  problem  containing  so  many 
-conditions  that  it  is  impossible  to  give  more  than  general  sug- 
gestions concerning  its  solution. 

In  order  to  possess  a  maximum  of  efficiency,  no  indication 
-of  the  position  of  a  mine  should  appear  on  the  surface  of  the 
M'ater,  and  yet  the  spot,  to  within  a  few  feet  of  where  it  is 
deposited,  must  be  known  to  the  defenders  of  the  channel  in 
which  it  is  used.  In  certain  cases — as  when  there  is  consider- 
able rise  and  fall  of  the  tide — it  is  impossible  to  totally  conceal 
the  position  of  a  system  of  mines.  When  such  is  the  case,  the 
very  smallest  indication  possible  should  be  allowed  to  appear  oil 
•the  surface  of  the  water.    It  has  been  found  that  the  least  cur- 


436  MOORING. 

rent,  or  so  much  roughness  as  only  a  moderate  breeze  would 
cause,  renders  the  placing  of  even  a  single  mine  in  a  definite 
position  a  matter  of  very  considerable  difficulty.  When  a  series 
of  mines  are  to  be  moored  in  proper  relative  position,  this  diffi- 
culty is  much  increased,  and  it  is,  furthermore,  augmented  in 
proportion  to  the  depth  of  the  water. 

The  objects  to  be  obtained  in  mooring  are  as  follows : 

1st.  That  the  charge  should  be  kept  as  nearly  as  possible  sta- 
tionary at  the  point  where  it  is  required  to  act.  This  is  partic- 
ularly necessary  where  there  is  a  tide  which,  flowing  first  in  one 
direction  and  then  in  another,  tends  to  cause  the  mine  to  shift 
its  position,  and  is  indispensable  in  the  case  of  mines  intended 
to  be  fired  by  judgment. 

2d.  The  moorings  should  be  so  arranged  that  there  shall  be  as 
little  twisting  as  possible,  which  might  break  or  injure  the  insu- 
lation of  the  electrical  cables. 

3d.  The  anchors  or  heavy  weights  used  should  be  suited  to 
the  nature  of  the  holding  ground  or  bottom. 

4th.  Mooring  cables  should  be  so  arranged  that  they  may  not 
be  likely  to  become  twisted  together  or  entangled. 

The  best  special  mooring  apparatus  for  general  purposes  fe 
the  mushroom  anchor,  {Fig,  1,  Plate  74.)  It  is  decidedly  so  for 
a  soft,  muddy  bottom.  On  a  hard,  rocky  bottom  the  dead-weight 
of  the  mooring  must  be  depended  upon  to  keep  a  mine  stationary, 
and  if  a  heavy  mushroom  anchor  is  used,  its  edges  should  be  fur- 
nished with  toes  or  points  to  catch  in  the  crevices  of  the  rocks. 
The  weight  of  the  anchor  would  depend  on  the  buoyancy  to  be 
overcome,  and  would  usually  be  from  500  pounds  upwards. 
Ordinary  mooring-chains  and  hemp  cables  may  generally  be 
employed  in  connecting  the  charges  or  circuit-closers  with  the 
anchors.  Where  there  is  any  tendency  to  twist,  a  wire  cable  is 
the  best  to  counteract  it.  Any  considerable  amount  of  twisting 
must  be  checked,  as  it  is  liable  to  entangle  the  moorings  and  to 
rub  and  injure  the  electric  cables. 

Next  to  the  mushroom  sinker  the  ordinary  anchor  is  the  best. 
For  make-shifts,  any  heavy  weights— as  large  stones,  pigs  of 
metal,  or  bars  of  iron — may  be  used.  These  must  necessarily  be 
sufficiently  heavy  to  hold  a  mine  in  position  simply  by  their 
dead-weight.  The  material  just  mentioned  can  be  fastened  to 
frames  of  wood,  and  the  whole  sunk  as  one  mass. 

The  weight  necessary  for  a  mooring,  whether  anchor,  sinker, 
or  other  apparatus,  will  depend  upon  the  buoyant  force  of  the 
mine,  the  nature  of  the  bottom,  and  the  currents. 

The  buoyancy  of  a  mine  is  its  excess  of  flotation  over  its 
weight.    This  would  be  measured  by  the  number  of  pounds 


MOORING.  437 

required  to  sink  it,  and  no  more.  When  wooden  casks  are  used 
the  buoyancy  may  be  roughly  taken  as  equal  to  the  weight  of 
the  charge  of  powder.  With  iieavy  metallic  cases  their  weight 
must,  in  ell  cases,  be  taken  into  consideration. 

In  water  free  from  currents  twice  its  buoyancy  is  considered 
necessary  to  keep  the  mine  in  a  vertical  position  over  the  moor- 
ing; this,  therefore,  would  be  the  weight  required  for  the  moor- 
ing. Where  there  is  a  current,  additional  weight  to  keep  it 
from  swinging  off  with  it  is  required,  and  this  increases  with  the 
strength  of  the  latter.  When  the  mine  is  moored  by  a  single 
cable,  a  convenient  rule,  approximating  closely  to  results  from 
experiments,  is  to  allow  one  additional  buoyancy  for  each  mile 
per  hour  of  current ;  i.  «.,  two  buoyancies  being  allowed  for  still 
water,  three  would  be  allowed  for  a  current  of  one  mile ;  four  for 
two  miles ;  five  for  three  miles,  and  so  ou.  These  represent  the 
weights  for  the  mooring  in  each  instance.  In  a  tide-way  where 
there  is  a  current  of  more  than  five  miles  an  hour,  two  anchors 
may  be  advantageously  used,  placed  up  and  down  stream  at  a 
considerable  distance  apart,  depending  upon  the  force  of  the 
-current  and  the  distance  from  the  bottom  at  which  the  mine  is 
to  float.  It  is  extremely  difficult  to  moor  mines  in  proper  lines 
and  depths  by  this  means. 

When  the  mine  is  small,  say  one  containing  a  charge  not 
greater  than  200  pounds,  a  single  large  barge  may  suffice  for 
placing  it.  The  anchors  can  be  let  down  at  a  suitable  distance 
apart  from  the  extremities  of  two  outriggers,  one  from  each 
end  of  the  barge.  The  mine,  attached  to  the  middle  of  the  cable 
connecting  the  anchors,  is  weighted  down  by  a  heavy  saddle, 
which,  after  the  anchors  are  down,  is  hoisted  in  and  the  mine 
permitted  to  rise  to  the  proper  depth  from  the  surface. 

In  order  to  place  a  large  buoyant  charge  of,  say,  1000  pounds 
and  upwards,  three  of  these  large  boats  are  required  to  cany  it 
and  its  anchors,  one  for  each  anchor  or  mooring  sinker,  and  one 
for  the  charge  itself.  They  are  connected  by  a  rope,  which,  if 
kept  stretched,  would  insure  the  anchors  being  placed  at  the 
proper  distance  apart.  The  sinkers  and  mine  are  carried  out 
and  lowered  from  the  davits  at  the  stern  of  each  boat.  Skillful 
boatmen  and  sailors  are  required  for  all  operations  connected 
with  the  placing  of  mines,  and  a  handy  steam-tug  is  the  most 
convenient  craft  to  use. 

The  floating  mine  is  used  where  the  depth  of  water  is  so  great 
that,  if  placed  on  the  bottom,  the  mine  would  require  for  effi- 
ciency an  excessively  large  charge.  In  this  case  it  is  held  to 
the  bottom  by  moorings  in  such  position  as  not  to  rise  to  the 
surface  at  low  tide,  nor  at  high  tide  be  so  deep  as  to  be  beyond 


438  LINES. 

effective  range  of  over-passing  vessels.  To  arrive  at  this  ex- 
act point,  it  is  best  to  haul  the  mine  down  towards  the  sinker. 
For  this  purpose  there  are  various  contrivances,  some  one  of 
which  would  be  supplied  with  the  rigging  furnished  with  the 
mine. 

When  the  mines  are  to  rest  upon  the  bottom,  they  are  lashed* 
to  some  heavy  object  sufficient  to  sink  and  hold  them  in  posi- 
tion, and  then  lowered  to  their  places. 

678.  Lines.  Submarine  mines  will  generally,  if  not  always, 
be  moored  in  straight  lines.  In  practice,  the  greatest  difficulty 
is  experienced  in  mooring  any  object  in  a  particular  spot,  espe- 
cially when  two  mooring-chains  are  required,  as  will  sometimes 
be  the  case,  to  prevent  twisting.  To  overcome  these  difficulties 
it  is  suggested  that  instead  of  anchors  a  heavy  chain  cable  be 
employed  to  moor  the  mines. 

UA  section  of  the  channel  to  be  defended  having  been  made 
from  soundings,  the  line  assumed  by  a  chain  could  be  laid  down 
to  scale.  The  positions  of  the  mines  and  their  distances  apart, 
depth  from  the  surface,  &c,  having  been  arrived  at  by  calcula- 
tion, could  also  be  laid  down  on  the  section.  The  points  where 
the  small  mooring-chains  of  each  mine  meet  the  large  chain 
would  appear  on  the  drawing,  and  the  distance  of  each  point 
from  either  extremity  having  been  measured  off,  the  scale  could 
be  marked  on  the  chain. 

"Before  sinking  the  heavy  chain  the  small  mooring-chains 
should  be  rove  through  the  links  at  the  places  marked,  and  the 
ends  buoyed,  sufficient  length  being  allowed  for  the  buoys  to 
reach  the  surface. 

"The  conducting  wires  could  next  be  laid  and  the  ends  at- 
tached to  the  same  buoys  which  support  the  mooring-chains.  In 
this  way  everything  could  be  prepared,  the  cables  tested,  &c., 
before  the  mines  were  required  at  all ;  indeed,  if  the  operation 
of  fixing  the  same  were  practiced  beforehand,  it  could  be  left 
out  until  there  was  considerable  probability  of  the  miues  being 
required  for  use.  By  keeping  the  mines  ready  loaded  in  suita- 
ble magazines,  and  having  the  cables  frequently  tested,  the 
probability  of  injury  would  be  greatly  diminished. 

"The  great  advantage  of  using  a  heavy  chain  would  be  the 
absolute  certainty  of  having  all  the  mines  in  their  proper  places; 
it  would  also  simplify  the  moorings  by  doing  away  with  a  mul- 
tiplicity of  anchors  and  anchor  buoys. 

44  A  2.5-inch  chain  cable  weighs  400  pounds  per  fathom.  The 
mines  would  probably  never  be  nearer  than  70  or  80  feet  apart,  8* 
it  is  evident  that  the  chain  would  be  quite  heavy  enough  to  coun- 
teract any  flotation  which  would  in  practice  be  given  to  the  mine. 


IGNITION    OF   CIIARGE.  439 

"In  a  current-  of  any  strength  it  would  be  necessary  to  use 
two  parallel  chains  across  the  current  to  prevent  the  mines 
swinging  with  the  change  of  tide,  but  the  same  advantages  would 
hold  good." 

Instead  of  a  chain  cable,  a  strong  hempen  cable  may  be  stretched 
across  the  channel.  Previous  to  immersion,  this  cable  is  marked 
at  intervals,  at  the  points  where  it  is  subsequently  intended  to 
lay  down  the  mines.  To  place  the  moorings  in  position,  the 
cable  is  slacked  up  sufficient  to  allow  of  its  being  underrun.  At 
each  point  marked  upon  it  to  indicate  the  position  of  a  mine,  one 
end  of  a  branch  hawser  is  bent  onto  it,  and  the  other  extremity 
made  fast  to  a  mushroom  anchor,  the  necessary  amount  of  slack 
being  left  to  allow  the  anchor  to  be  passed  into  its  proper  posi- 
tion. A  buoy  is  attached  to  the  mooring  cable  fastened  to  the 
anchor ;  the  latter  is  then  carried  out  to  one  side  of  the  directing 
cable  and  dropped  into  its  place.  Any  further  arrangement  for 
attaching  the  charge,  the  electrical  cable,  and  circuit-closer  may 
be  carried  on  without  difficulty. 

Fig.  2,  Plate  74,  represents  this  method  of  planting  mines;  a, 
6,  c,  dj  &c,  are  the  mooring-chains  attached  to  the  hawser  HH. 
This  plan  affords  considerable  facilities  for  the  examination  of 
charges  after  they  have  been  submerged,  as  it  would  be  necessary 
only  to  underrun  the  main  hawser  until  the  required  branch 
hawser  is  reached,  and  then  by  it  raise  the  mooring  anchor,  and 
with  it  the  mine  to  be  examined.  In  the  event  of  the  main  haw- 
ser being  broken,  it  would  not  be  a  verj'  difficult  operation  to 
grapple  it  and  bring  it  to  the  surface  for  repair. 

6'i9.  Ignition  of  charge.  For  mechanical  mines  various  con- 
trivances have  been  used.  All  those  constructed  on  the  princi- 
ple of  the  gun-lock  have,  however,  been  found  to  soon  become 
worthless  from  oxidation  and  incrustation  of  the  more  delicate 
parts.  A  very  simple  form  is  the  nipple,  upon  which  is  placed  a 
percussion  cap,  but  this  is  apt  to  become  damaged  when  im- 
mersed. Another  kind  is  uthe  well-known  sulphuric-acid  fuse, 
formed  on  the  principle  of  ignition  by  sulphuric  acid  dripped 
upon  a  mixture  of  equal  parts  of  chlorate  of  potash  and  loaf- 
sugar.  The  sulphuric  acid  is  placed  in  a  small  glass  globe,  which 
is  so  arranged  as  to  be  broken  bjr  the  blow  given  on  touching  the 
side  of  a  vessel,  and  the  acid  set  free,  falling  on  the  mixture  of 
chlorate  of  potassa  nnd  loaf-sugar,  produces  the  required  igni- 
tion." The  ignition  produced  by  this  means  is  comparatively 
slow;  it  has,  however,  been  found  that  an  addition  of  one-third 
of  ferro-cyauide  of  potassium  to  the  mixture  of  equal  parts  of 
chlorate  of  potash  and  loaf-sugar  produces  an  ignition  as  rapid 
as  that  of  gunpowder.    The  glass  globe  is  best  inclosed  in  a  lead 


440  ELECTRICAL   FUSE. 

tube,  which,  by  bending  or  being  crushed  by  the  blow,  breaks 
the  glass.  This  is  the  fuse  sometimes  used  for  land  torpedoes. 
(Par.  646.) 

To  secure  the  fuse  and  charge  from  moisture,  a  composition 
made  of  1  part  of  tallow,  8  of  pitch,  and  1  of  bees-wax  will  be 
found  good.  To  this  may  be  added  a  little  gutta-percha,  which 
will  have  a  tendency  to  harden  it.  This  composition,  when  soft- 
ened by  heat,  is  pressed  around  the  fuse-plug. 

The  great  superiority  of  electrical  fuses  over  mechanical,  causes 
the  latter  to  be  employed  only  under  exceptional  circumstances. 
The  universal  use  of  the  electric  telegraph  makes  it  easy  to  ob- 
tain all  material  and  apparatus  necessary  for  firing  submarine 
mines;  even  fuses  are  an  article  of  commerce,  and  there  is  no 
difficulty,  if  required,  in  obtaining  the  services  of  electricians  or 
other  operators  capable  of  arranging  and  manipulating  all  parts 
of  it. 

680.  An  electrical  fuse  consists  essentially  of  a  priming  of  or- 
dinary sporting  powder,  gun-cotton,  or  of  a  mixture  of  the  two, 
in  contact  witli  which  is  the  conducting  wire  of  a  galvanic  battery 
arranged  at  this  point  in  such  manner  as  to  generate  heat  by  the 
passage  of  the  electric  current.  The  fuse  is  imbedded  in  the 
charge  of  the  mine,  and  the  conducting  wires  passed  out  from  it 
through  a  water-tight  plug  or  bung-stopper  in  the  case,  and  are 
connected  with  the  electrical  cable  passing  to  the  operating  case- 
mate of  the  fort. 

The  platinum  fuse  is  formed  of  a  very  fine  piece  of  platinum 
wire  ^  of  an  inch  long,  to  the  extremities  of  which  are  soldered 
the  two  ends  of  the  conducting  wire;  the  priming  is  secured  in 
contact  with  the  platinum,  which  latter  is  fused  by  the  passage 
of  the  electric  current. 

This  fuse  requires  a  battery  producing  a  current  of  large  quan- 
tity. Grove's,  Bunsen's,  and  Walker's  are  among  those  most 
suitable  for  such  fuses. 

Platinum  may  be  dispensed  with  by  bringing  the  ends  of  the 
conducting  wires  so  close  together  as  barely  to  be  apart,  thus 
forming  a  break  or  interval  in  the  conductor.  The  ends  of  the 
wire  are  held  in  exact  position,  usually  by  being  passed  through 
a  short  plug  of  wood.  Around  this  plug  is  wrapped  paper, 
which,  projecting  at  the  end  where  the  conductor  is  broken, 
forms  an  envelope  for  the  priming.  This  wrapping  or  cap  is 
afterwards  covered  with  a  strong  shellac  varnish. 

When  regularly-manufactured  fuses  cannot  be  obtained,  it  may 
become  necessary  to  improvise  them.  This  may  be  done  in  sev- 
eral ways,  one  of  which  is  to  take  a  small  cylinder  of  hard  wood 
(Fig,  3,  Plate  74)  about  an  inch  in  diameter  and  half  an  inch 


POSITION   OF   FUSE.  441 

long;  this  is  provided  with  a  groove  around  its  circumference,  in 
which  is  tied  the  paper  envelope  before  mentioned.  Two  holes 
about  a  quarter  of  an  inch  apart  and  of  suitable  size  to  receive 
two  moderately-fine  pieces  of  copper  wire  are  made  lengthwise 
through  the  cylinder.  One  extremity  of  both  of  these  wires  is 
sharpened  with  a  file,  and  about  a  quarter  of  an  inch  of  the 
wire  bent  over  at  right  angles,  and  slightly  flattened  with  a 
hammer,  the  extreme  point  being  bent  over  in  the  form  of  a 
hook.  The  straight  ends  of  the  wire  are  then  passed  through 
the  holes  in  the  cylinder,  and  the  flattened  heads  are  fixed  in  the 
wood  by  driving  the  pointed  extremities  into  the  latter.  In  this 
way  the  broad,  thin  metal  surfaces  which  form  the  poles  of  the 
fuse  are  fixed  in  a  parallel  position  on  the  surface  of  the  wood, 
and  should  be  as  close  together  as  possible  without  actually 
touching.  Before,  however,  the  wires  are  thus  placed  in  posi- 
tion, the  surface  of  the  cylinder,  upon  which  the  poles  are  to 
be  fixed,  is  brushed  over  lightly  with  a  solution  of  ordinary 
photographic  collodion.  When  the  poles  have  been  fixed  into 
the  cylinder  thus  prepared,  the  small  surface  of  wood  which  in- 
tervenes between  them  is  coated  with  graphite  by  drawing  a 
pointed  black-lead  pencil  across  it  two  or  three  times.  A  cap  of 
paper  is  then  tied  round  the  cylinder  so  as  to  inclose  the  poles  of 
the  fuse;  this  cylinder  is  filled  compactly  with  fine  gunpowder, 
and  the  open  end  is  then  choked. 

The  protruding  wires  of  the  fuse,  which  serve  to  connect  it 
with  the  conducting  wires,  are  coated  to  within  a  short  distance 
of  their  extremities  by  moulding  ordinary  bees-wax  around  rhem 
with  the  fingers,  and  then  tightly  wrapping  the  wax  with  thin 
strips  of  tape  or  rag,  which  is  secured  to  the  ends  with  thread. 
The  entire  fuse,  except  the  bare  ends  of  the  wires,  is  then  coated 
with  shellac  or  lacquer. 

This  fuse  may  be  fired  by  means  of  a  constant  battery  of  suf- 
ficient power,  or  by  a  magnetic  exploder,  the  former  of  which 
generates  a  continuous  current,  and  the  latter  a  rapid  succession 
of  short  currents.  Currents  of  this  character  are  required  to 
produce  the  heating  power  over  the  plumbago  bridge  necessary 
to  ignite  the  priming. 

681.  Position  of  the  fuse  in  a  charge.  "It  has  been  already 
stated  that,  in  order  to  develop  the  full  explosive  effect  of  even 
a  small  charge  of  powder  when  fired  under  water,  a  very  strong 
case  is  required;  with  very  small  charges  this  is  quite  practica- 
ble, but  for  large  charges  of  500  pounds  and  upwards  it  is  quite 
impossible  to  make  cases  proportionately  stiong,  because  they 
would  become  enormously  heavy.  This  difficulty,  however,  to 
a  certain  extent,  may  be  overcome  by  igniting  the  charges,  when 


442  POSITION   OF   FUSE. 

of  a  large  size,  at  several  points,  providing,  in  fact,  centres  of 
ignition,  and  thus  burning  as  much  as  possible  of  the  charge 
and  converting  it  into  gas  before  the  envelope  is  broken  and  the 
water  admitted. 

"The  radius  of  ignition  due  to  a  single  fuse,  when  fired  under 
the  circumstances  above  described,  is  supposed  to  be  about  one 
foot,  and  starting  with  this  basis,  the  maximum  charge  to  be 
fired  from  a  single  centre  of  ignition  is  at  oncu  determined  to  be 
about  250  pounds.  Therefore  a  single  centre  of  ignition  may  be 
used  for  all  charges  of  less  than  250  pounds  of  powder,  adding 
a  fresh  fuse,  suitably  placed,  for  each  additional  250  pounds  or 
fraction  of  250  pounds  in  the  charge  to  be  fired. 

"This  has  reference  to  gunpowder  tired  with  an  ordinal  fuse* 
When  gun-cotton  and  a  detonating  fuse  are  used,  a  much  greater 
bulk  may  be  exploded  from  a  single  centre  of  ignition. 

"The  distribution  and  holding  in  proper  relative  position  of  a 
number  of  fuses  in  a  large  charge  of  powder  is  a  matter  of  some 
little  nicety,  and,  in  addition,  there  is  the  increased  difficulty  of 
testing  the  fuses  after  being  placed  in  the  charge,  and  the  in- 
creased chance  of  failure  and  trouble  in  replacing  a  defective 
fuse  or  adjusting  any  accidental  derangement  of  the  conducting 
wires  should  a  defect  occur  in  the  heart  of  the  charge  itself, 
which  would  render  the  emptying  out  of  the  case  necessary." 
In  order  to  obviate  these  defects,  it  is  suggested  to  use  a  brass 
tube  and  a  single  fuse  primed  with  powder. 

The  brass  tube  should  be  sufficiently  long  to  run  the  whole 
length  of  the  charge,  and  should  have  an  internal  diameter  of 
about  1  inch.  Slits  0.5  inch  wide  and  1.5  inches  long  are  cud 
at  central  intervals  of  3  inches,  following  a  spiral  line  around 
the  tube.  These  slits  should  be  covered  with  a  brass- wire  gauze, 
of  a  mesh  sufficiently  small  to  exclude  the  powder  of  the  charge. 
One  end  of  this  tube  is  closed  and  the  other  arranged  to  receive 
and  hold  the  fuse. 

A  fuse  primed  with  about  one-fourth  of  an  ounce  of  powder  ia 
placed  in  the  end  of  the  tube  and  well  secured.  The  tube  is 
then  put  in  the  central  line  of  the  charge  and  secured  so  that  it 
shall  not  vary  its  position.  On  igniting  the  fuse,  jets  of  gas  and 
flame  are  driven  from  the  openings  in  the  tube  and  fire  the  pow- 
der within  reach.  The  result  is  the  complete  ignition  of  the  out- 
lying portions  even  before  the  gas  evolved  by  the  grains  first 
ignited  has  time  to  rupture  the  case  and  let  in  water.  Two  or 
more  fuses  may  be  attached  to  the  same  tube,  so  that  in  the  event 
of  one  of  them  failing,  ignition  may  be  secured  through  another. 

Instead  of  using  a  tube,  a  pound  or  two  of  gun-cotton  may  be 
placed  in  actual  contact  with  the  fuse;  and  this  substance  being 


ELECTRIC    CABLES.  44* 

much  quicker  of  ignition  than  gunpowder,  the  gas  and  flame 
produced  are  sufficient  to  permeate  the  interstices  between  the 
grains  of  the  latter  and  thus  secure  a  thorough  combustion  of 
the  charge. 

682.  Electric  cables.  The  qualifications  required  for  these 
are  as  follows : 

"1st.  Capacity  to  bear  a  certain  amount  of  strain  without 
breaking. 

"2d.  Good  insulation,  composed  of  such  a  substance  that  it 
may  be  readily  stored  and  kept  for  a  considerable  time  without 
being  injured.  This  is  essential,  as  the  lines  will  only  be  sub- 
merged while  actually  in  use  in  time  of  war,  for  which  purpose 
they  must  consequently  be  kept  in  store,  and  always  ready  in 
sufficient  quantities. 

fcft  3d.  For  situations  where  there  is  a  rocky  or  shingly  bottom, 
they  must  be  provided  with  an  external  covering  capable  of 
protecting  the  insulation  from  destruction.  Special  precautions 
must,  of  course,  be  taken  to  secure  the  cables  at  points  where 
they  may  be  necessarily  exposed  to  a  considerable  wasli  of  the 
sea,  such  as  the  places  where  they  may  be  led  into  a  fort,  &c; 
but  as  there  are  others  where  no  such  special  precautions  can 
be  applied,  an  external  protecting  covering  over  the  insulation 
must  be  provided. 

tfc  4th.  Pliability,  so  that  it  may  be  wound  or  payed  out  from  a 
moderately-sized  drum  without  injury.  The  conducting  wire  is 
either  soft  iron  or  copper.  The  best  substance  for  covering  it  to 
effect  insulation,  is  vulcanized  India  rubber;  this  is  capable  of 
standing  any  degree  of  heat  likely  to  occur  to  a  cable,  and  docs 
not  harden  and  crack  as  does  gutta-percha.  The  conductor 
should,  however,  be  galvanized  and  covered  with  a  thin  coating 
of  raw  India  rubber,  to  protect  it  from  the  action  of  the  sulphur 
of  the  vulcanized  rubber. 

"  India  -rubber  insulation  possesses  one  defect  as  compared 
with  gutta-percha,  viz.,  that  it  does  not  adhere  to  the  metallic 
conductor;  and  that,  consequently,  if  the  India  rubber  is  once 
cut  through,  any  strain  on  the  cable  has  a  tendency  to  pull  the 
conductor  away  and  increase  the  fault.  This  does  not  occur 
with  gutta-percha,  which  seems  to  cling  to  it  and  prevent  such  a 
result.  Gutta-percha  cracks  and  perishes  unless  considerable 
care  is  exercised  in  preserving  it,  which  is  best  done  by  keeping 
it  under  water.  India  rubber  possesses  higher  dialectric  proper- 
ties than  gutta-percha." 

Ordinary  gutta-percha  and  India-rubber  insulated  wire  is  an 
article  of  commerce,  and  is  the  kind  that  in  most  cases  would 
be  used  for  submarine  mines ;  but,  as  before  stated,  where  there- 


444  BUNG-STOPPERS — JOINTS. 

is  any  strain,  or  any  chance  for  abrasion  against  rocks  or  grav- 
elly bottom,  an  exterior  covering  is  necessary  for  protection. 
The  ordinary  American  form  of  submarine*  cable  is  the  most 
suitable.  The  smallest  size,  such  as  is  used  for  crossing  rivers 
and  harbors,  is  quite  sufficient,  except,  perhaps,  in  some  cases. 

A  multiple  cable  may  in  many  cases  be  found  convenient 
where  it  is  required  to  carry  a  large  number  of  wires  in  a  com- 
pact form  into  a  fort. 

It  is  composed  of  seven  distinct  cores,  each  of  which  consists 
of  a  strand  of  copper  or  iron  wire  insulated  with  rubber  or  gutta- 
percha. For  a  rocky  bottom,  or  situation  where  the  cable  is  lia- 
ble to  injury,  a  further  external  covering  of  iron  wires  and  tarred 
hemp,  laid  on  as  usual  for  the  protection  of  submarine  cables, 
^becomes  necessary. 

Frictional  electricity  must  not  be  used  with  such  cables,  as  it 
would  be  nearly  certain  that  every  mine  attached  to  the  cable 
would  explode  by  induction. 

683.  Bung-stoppers  are  the  contrivance  for  closing  the  hole 
in  the  case  through  which  the  charge  is  inserted,  and  through 
which  the  insulated  wires  pass  from  the  fuse  to  the  cable  leading 
to  the  fort.  The  essential  condition  to  be  fulfilled  is  to  have  it 
water-tight  and  keep  the  arrangement  in  proper  condition  for 
ignition  at  any  moment  required;  it  should  likewise  be  capable 
of  being  unscrewed,  so  that  the  fuse  may  be  taken  out  for  exam- 
ination and  replacement  if  defective. 

Various  forms  of  stoppers  have  been  devised,  the  principal  feat- 
ure of  each  being  a  stuffing-box,  in  which  gutta-percha  packing 
Is  used.  When  regularly-constructed  mines  are  supplied  for  serv- 
ice, stoppers  will  accompany  them.  For  extemporized  mines, 
-any  device  which  will  hold  the  insulated  wires  and  at  the  same 
time  keep  the  water  from  the  charge  will  answer.  A  composi- 
tion composed  of  1  part  of  tallow,  8  of  pitch,  and  1  of  bees-wax 
will  be  found  good  for  tightening  the  joints.  It  becomes  plastic 
at  about  150°  F.  The  addition  of  a  little  gutta-percha  hardens 
the  composition,  and  renders  it  less  liable  to  be  affected  by  at- 
mospheric heat. 

684.  Joints.  This  is  a  very  important  point  in  connection 
with  a  system  of  mines.  In  many  instances  it  will  be  found 
necessary  to  join  either  two  lengths  of  cable,  or  an  insulated 
wire  and  a  cable,  together,  in  both  of  which  cases  great  care 
must  be  used  in  making  the  joints,  so  that  the  insulation  and 
the  continuity  of  the  circuit  may  be  perfect. 

In  making  a  joint,  the  great  object  is  to  totally  exclude  the 
ingress  of  water,  or  even  moisture,  which  would  at  once  afford 
a  path  for  the  current  and  cause  a  loss  or  a  leak  in  the  cable. 


LAYING   SUBMARINE  MINES.  445> 

Various  methods  of  forming  joints  are  in  use  and  prove  effective. 
These  are  explained  in  works  on  submarine  telegraphy,  and  are 
well  known  to  those  engaged  in  that  business. 

685.  Buoys,  These  are  used  for  temporarily  marking  the- 
positions  of  mines,  circuit -closers,  &c.  Small  nut-buoys  of  iron 
are  the  best,  but  when  these  are  not  to  be  had,  empty  casks,  such 
as  beer-kegs,  well  lashed  with  rope,  are  convenient  to  handle, 
and  answer  every  purpose.  In  all  cases  they  must  be  sufficiently 
large,  or  have  enough  of  flotation  to  secure  the  mooring  cable  or 
other  object  which  they  are  intended  to  hold. 

686.  Laying  submarine  mines.  "The  position  of  the  mines 
having  been  first  determined,  should  be  marked  off  by  means  of 
buoys  arranged  to  correspond  with  the  mines  to  be  subsequently 
placed  in  position,  and  points  on  shore  are  marked  to  guide  the 
vessels  employed  in  laying  them.  A  complete  chart  of  the  whole 
is  made  to  guide  in  subsequent  operations.  The  moorings  may 
either  be  first  placed  in  position,  and  the  mines  and  circuit-closers 
hauled  down  to  them,  or  the  whole  (moorings,  mines,  and  circuit- 
closers)  may  be  launched  overboard,  attached  together  in  proper 
relative  positions,  at  the  same  time.  In  deep  water  it  would  prob- 
ably be  found  preferable  to  adopt  a  system  of  hauling  down  to- 
moorings  previously  placed,  while  in  shallow  water  it  would,  un- 
der certain  circumstances,  be  found  quicker  and  more  convenient 
to  adopt  the  latter  mode  of  proceeding.  The  cases  ready  charged 
and  with  the  electrical  cables,  &c.,  attached,  having  been  low- 
ered into  position  at  such  intervals  as  may  be  required,  according 
to  the  size  of  the  charges  to  be  used,  and  each  carefully  marked 
with  a  numbered  buoy,  the  paying  out  of  the  electrical  cables 
may  be  proceeded  with.  The  cable  attached  to  each  having  been 
previously  arranged  on  a  drum,  is  placed  on  board  a  launch, 
which  proceeds  to  pay  it  out  in  a  line  as  nearly  as  possible  per- 
pendicular to  the  line  of  the  mines.  (Fig.  4,  Plate  74.)  Each 
boat  should  be  provided  with  a  small  testing  battery  and  astatic 
galvanometer,  by  which  the  insulation  and  electrical  resistance 
of  the  system  is  tested  at  intervals  from  the  moment  of  submerg- 
ing the  mine  till  the  other  extremity  of  the  cable  is  safely  lodged 
in  the  testing-room.  Any  defect  likely  to  cause  a  failure  in  firing 
at  the  proper  moment  would  in  this  way  be  immediately  discov- 
ered during  the  operation  of  submergence.  As  the  boat,  in  pay- 
ing out  the  cable,  passes  the  position  marked  out  for  the  second 
or  covering  line  of  mines,  care  should  be  taken  to  have  it  as  near- 
ly as  possible  midway  between  two  adjacent  mines  in  this  line. 
In  passing  this  line  the  position  of  the  electric  cables  should  be 
marked  off  by  buoys  as  a  guide  to  those  laying  down  the  second 
line  of  mines,  which,  as  soon  as  the  work  of  the  first  has  pro- 


446  LAYING   SUBMARINE   MINES. 

■ceeded  thus  far,  may  at  once  be  commenced.  In  order  to  distin- 
guish between  the  buoys  marking  the  positions  of  the  mines  from 
those  indicating  the  direction  of  the  cables,  different  colors  are 
-used.  As  the  third  line  of  mines  would  be  placed  to  cover  the 
intervals  of  the  second,  it  would  be  necessary,  after  proceeding 
in  a  direct  line  for  about  100  yards  in  rear  of  the  second  line  of 
mines,  to  change  the  direction  in  which  the  cable  is  to  be  laid  by 
carrying  it  perpendicularly  to  the  direction  hitherto  followed  till 
^  point  directly  in  rear  of  some  one  of  the  mines  of  the  second 
line  is  reached,  when  it  is  again  turned  inward  to  a  position  to 
pass  safely  through  the  centre  of  an  interval  between  two  mines 
of  the  third  line,  as  it  had  previously  passed  through  those  of  the 
second.  In  passing  this  third  line  of  mines  it  should  again  be 
buoyed  for  guidance  in  laying  the  mines  belonging  thereto,  and 
so  on  till  the  extremity  of  the  cable  is  connected  to  its  corre- 
sponding wire  in  the  multiple  cable,  or  if  taken  in  singly,  till 
safely  landed  in  the  fort  in  which  the  opeiating-room  is  placed, 
when  it  is  attached  to  its  proper  binding-screw,  and  its  insulation 
and  resistance  carefully  tested  and  registered. 

"The  same  process  is  gone  through  with  every  charge,  the  ut- 
most care  being  taken  to  so  lay  the  cables  that  they  shall  be  as 
far  as  possible  away  from  the  mines  in  the  vicinity  of  which  they 
may  be  required  to  pass.  By  the  arrangement  just  described 
they  are  also  in  a  favorable  position  for  underrunning  and  pick- 
ing up,  should  such  an  operation  become  necessary.  A  certain 
amount  of  slack,  depending  on  the  depth  of  water,  should  be 
allowed  in  lajing  the  cables  to  facilitate  this  operation. 

"The  position  of  each  mine  should  be  identified  by  means  of 
bearings  taken  by  two  theodolites,  from  points  well  situated  for 
the  purpose,  and  marked  in  position  on  the  plan,  with  the  num- 
ber of  each  mine,  as  a  guide  to  facilitate  its  discovery  at  any  fu- 
ture time.  This  done,  and  the  whole  system  having  been  proved 
to  be  electrically  correct,  all  the  surface  buoys  should  be  removed, 
to  prevent  any  indication  of  their  position  being  given  to  an  en- 
-emy.  Dummies  to  deceive  an  enemy  may  be  judiciously  arranged 
in  a  manner  not  too  ostentatious,  but  they  should  never  be  placed 
■in  such  a  position  as  might,  in  ever  so  remote  a  manner,  lead  to 
the  discovery  of  a  real  mine.  The  cables  should  be  laid  as  far  as 
possible  parallel,  and  never  be  allowed  to  cross  directly  over  each 
other;  otherwise  the  operation  of  underrunning  will  be  much 
■complicated. 

"The  arrangement  of  cables  just  described  is  that  in  which 
the  shortest  possible  length  would  be  consumed.  In  certain 
cases,  however,  it  might  be  desirable  to  carry  them  by  a  detour 
to  the  fort,  as,  for  example,  around  the  flank  of  the  second  and 


PLANTING  THE   MINES.  447 

third  lines  of  mines,  and  there  is  no  difficulty  in  this,  always 
bearing  in  mind  that  they  should,  in  the  first  instance,  he  carried 
directly  back  for  about  100  yards,  so  as  to  be  safe  from  injury 
due  to  the  explosion  of  their  own  line  of  mines,  and  that  their 
subsequent  course  should  be  so  arranged  as  to  k*  ep  them  safe 
from  damage  from  the  explosion  of  any  other  mine  in  the  sys- 
tem. 

"In  selecting  any  line  to  be  taken,  places  where  the  cables 
would  be  subjected  to  a  wash  of  the  sea  should  be,  as  much  as 
possible,  avoided ;  and  when  it  becomes  necessary  to  place  them 
in  positions  where  they  are  necessarily  subjected  to  the  friction 
and  rubbing  consequent  upon  the  motion  of  the  water,  special 
precautions  must  be  employed  for  their  protection.  A  good 
method  of  doing  this  is  to  lash  the  cable  securely  to  a  chain 
heavy  enough  to  keep  it  in  position  on  the  bottom.  A  wire-cov- 
ered cable  of  ordinary  size  will  have  weight  of  Itself  sufficient  to 
hold  it  steady  on  the  bottom." 

Jn  all  cases  the  cables  should  be  laid  where  they  will  be  sub- 
jected to  the  greatest  amount  of  supervision,  and  where  they 
can  be  most  easily  defended  from  injury  by  an  enemy. 

L»ines  of  mines  should,  when  practicable,  be  directed  on  a 
point  where  an  observer  can,  in  security,  observe  the  crossing  of 
the  lines  by  a  vessel  of  the  enemy.  This  point  should  be  in  elec- 
trical communication  with  the  fort  containing  the  operating- 
room  ;  if  not  by  electrical  communication,  then  by  signaling. 
The  bearing  of  each  mine  is  taken  from  the  operating-room  as 
it  is  put  down.  By  means  of  observation  from  these  two  points 
it  is  determined  when  the  vessel  is  over  any  particular  mino, 
and  then  the  charge  is  exploded. 

The  direction  of  a  line  of  mines  may  be  determined  by  two 
poles  previously  erected  on  the  shore.  These  serve  as  ranges. 
The  interval  between  the  mines  on  the  line  are  best  determined 
with  a  cord  measured  and  marked  to  the  exact  length.  In  many 
positions  it  may  be  practicable  to  erect  range-poles,  the  lines  of 
which,  intersecting  the  line  of  the  mines,  will  establish  the 
points  for  the  respective  mines.  It  is  impossible  to  lay  down 
rules  for  each  case  which  may  arise  in  service;  the  ingenuity 
•of  those  in  charge  must  be  relied  upon  to  solve  the  particular 
problem. 

68*7.  Planting  the  mines.  The  following  will  indicate,  gen- 
erally, the  manner  of  planting  the  mines.  The  positions  having 
been  determined  as  just  explained,  soundings  arc  taken  at  each 
one,  and  the  length  of  the  mooring-line  for  each  charge  deter- 
mined accordingly.  The  anchor  is  suspended  from  the  davits 
of  the  working-boat,  and  everything  made  ready  to  let  it  go  with 


448  PLANTING   THE   MINES. 

a  run.  The  electric  cable  is  stoppered  to  the  mooring-line  be- 
tween the  charge  and  the  anchor,  and  a  strong  mooring-chaiu 
or  wire  rope  is  provided  to  connect  the  charge  to  the  circuit- 
closer,  so  that,  by  this  chain,  both  the  charge  and  anchor  may 
be  raised  if  required.  The  electric  cable  between  the  circuit- 
closer  and  charge  should  be  stoppered  from  the  chain  to  the  wire 
rope  in  the  same. manner  as  from  the  charge  to  the  anchor.  The 
length  of  the  electric  cables,  from  the  anchors  of  the  different 
charges  to  the  point  where  they  are  united  to  go  into  the  fort, 
are  determined,  and  each  one  coiled  on  a  small  portable  drum, 
so  that  it  may  be  easily  moved  in  and  out  of  the  boat. 

"To  place  the  first  charge,  the  boat  (with  the  anchor  con- 
nected to  the  charge  and  circuit-closer  by  moorings  of  proper 
length,  as  above  described,  and  suspended  from  the  davits  at  the 
stern)  is  turned  out  into  the  exact  alignment  of  the  poles  mark- 
ing the  line  of  mines,  proceeding  only  fast  enough  to  obtain 
steerage-way ;  as  soon  as  the  stern  of  the  boat  arrives  at  the  point 
marked  out  for  the  mine,  fclet  go '  is  given,  and  immediately  an- 
chor, charge,  and  circuit-closer  are  dropped  into  position.  The 
electric  cable  is  then  payed  out,  at  first  directly  away  from  the 
charge,  and  finally  taken  to  the  fort.  The  next  charge,  with  all 
its  attachments  complete,  having  been  arranged  as  before,  the 
boat  is  again  moved  slowly  across  the  channel  along  the  align- 
ment till  her  stern  arrives  at  the  point  for  the  next  mine,  the 
anchor  is  let  go,  and  the  cable  disposed  of  as  before.  Thus  all 
the  charges  of  a  line  are  deposited." 

It  is  advantageous  to  have,  during  the  operation,  a  boat  an- 
chored at  some  central  point  about  100  yards  in  rear  of  the  rear 
line  of  mines.  To  this  boat  all  the  electric  cables  of  each  line  of 
mines  are  brought.  This  dispenses  with  the  use  of  long  cables, 
and  consequently  unwieldy  drums.  Furthermore,  from  this 
point  to  the  fort  a  multiple  cable  may  be  used,  or  if  single,  they 
may  be  tied  together  with  spun-yarn  and  laid  out  as  one.  When 
everything  is  completed  the  boat  is  removed,  its  position  having 
been  previously  determined  by  bearings,  to  facilitate  any  future 
search  for  the  cables  at  that  point.  All  range-poles  are  removed, 
their  positions  having  been  carefully  marked,  but  without  leaving 
any  indications  to  guide  the  enemy  in  ascertaining  the  locality  of 
the  mines. 

The  first  line  of  mines  having  been  completed,  the  next  is  laid 
in  the  same  manner,  and  so  likewise  the  third. 

In  working  from  a  chain  or  hawser  on  which  the  distances 
have  been  marked,  as  heretofore  described,  ranges  are  used  in 
the  same  manner,  to  guard  against  any  error  caused  by  the  sag- 
ging of  the  chain  or  cable. 


THE  TESTING-BOOM.  449 

Junction-boxes.  When  it  is  necessary  to  employ  a  multiple 
cable,  a  junction-box  is  used  to  facilitate  the  connection  of  the 
several  separate  wires  diverging  from  the  extremities  of  such  a 
cable.  In  one  angle  of  such  a  box  the  multiple  cable  is  intro- 
duced, while  the  separate  cables  make  their  exit  on  the  opposite 
sides  and  pass  to  different  mines. 

The  ends  of  the  cables  are  secured  from  pulling  out  by  hooked 
nippers.  Each  multiple  cable  is  composed  of  seven  cores,  and 
each  of  these  is  connected  by  means  of  joints  with  the  mine 
cables  within  the  junction-box.  The  boxes  are  usually  made  of 
cast  metal,  and  must,  as  an  essential  condition,  be  perfectly 
water-tight.  They  are  of  various  forms,  depending  upon  the 
object  for  which  each  is  to  be  used.  They  would  be  supplied 
with  the  other  apparatus  for  laying  mines. 

A  junction-box  should  be  placed  in  such  a  position  as  to  be 
easily  attained,  even  in  the  presence  of  an  enemy,  and  its  buoy 
should,  if  possible,  not  be  seen.  It  is  also  very  essential  that  it 
should  be  in  a  safe  and  guarded  position,  for  any  injury  to  the 
junction-box  or  multiple  cable  would  be  fatal  to  the  group  of 
mines  in  connection. 

688.  uThe  next  point  to  be  considered  is  the  best  mode  of 
introducing  the  cables  into  a  fort.  In  doing  so  they  should  be 
protected  to  the  utmost,  not  only  from  injury  by  an  enemy,  but 
from  the  friction  and  rubbing  necessarily  caused  by  the  wash  of 
the  sea.  Bearing  these  objects  in  view,  advantage  must  be  taken 
of  local  circumstances,  which,  presenting  an  endless  variety  of 
conditions,  must  be  met  by  expedients  suited  to  the  nature  of 
each  particular  case.  As  already  stated,  they  should  be  earned 
into  such  forts  and  positions  as  are  likely  to  hold  out  longest  in 
any  system  of  defense,  and  not,  as  a  matter  of  course,  into  those 
nearest  to  them.  They  must  be  covered  to  the  utmost  from  an 
enemy's  fire,  and,  as  far  as  possible,  be  protected  from  his  inter- 
ference in  any  way,  as  his  great  object  would  be  to  break  and 
destroy  the  electrical  current." 

689.  The  testing-room  is  in  the  most  secure  part  of  the  work. 
It  should  be  about  16  feet  square,  with  a  suitable  store-room 
attached.  From  the  testing-room  a  gallery,  about  4  feet  wide 
by  5  high,  passes  out  through  or  under  the  fort.  In  this  gallery 
are  placed  frames  for  supporting  the  cables,  so  arranged  that 
there  will  be  no  confusion  as  to  the  identity  of  the  cables.  The 
frames  should  be  of  bronze;  iron  is  apt  to  oxidize,  and  wood  is 
liable  to  decay  and  render  constant  repairs  necessary.  The; 
frames  occupy  half  the  breadth  of  the  gallery,  leaving  the  other 
half  for  access  and  examination  of  the  cables.    Each  cable  is 

29 


450  FIRING. 

attached  to  a  binding  screw  of  the  testing-table,  the  binding 
screws  being  numbered  to  correspond  with  the  mines. 

In  the  testing-room  is  the  apparatus  for  producing  the  agent 
by  which  the  mines  are  to  be  exploded.  This  may  be  frictional 
electricity,  a  magnet  current  generated  by  a  dynamo-electrical 
machine,  but  usually  it  is  a  galvanic  current  similar  to  that  for 
electric  telegraph  purposes.  The  main  conditions  for  such  a 
battery  are,  that  it  should  remain  constant — that  is,  that  it  should 
be  capable  of  being  allowed  to  remain  mounted  and  ready  for 
use  for  sajr  a  month — and  that  it  shall  generate  a  sufficient  quan- 
tity of  electricity  to  allow  of  a  certain  amount  of  leak  or  fault  in 
a  cable  and  yet  fire  a  fuse  beyond  the  leak. 

The  LeclancM  battery  is  the  one  best  adapted  and  most  gener- 
ally used.  The  advantages  possessed  by  it  are,  the  absence  of 
chemical  action  when  the  battery  circuit  is  not  complete,  and 
consequent^  there  is  no  waste  of  material.  It  requires  but 
little  looking  after.  It  may  be  kept  ready  for  action  in  store 
"without  in  any  way  deteriorating,  and,  finally,  it  is  compara- 
tively inexpensive. 

690*  Firing.  The  efficiency  of  a  mine  or  system  of  mines 
•depends  upon  the  accuracy  and  certainty  with  which  they  may 
he  discharged  at  the  right  moment,  this  moment  being  when  the 
hostile  vessel  is  directly  over  any  particular  mine  of  the  group. 
This  may  be  done  at  will,  the  position  of  the  ship  having  been 
<letermined  by  intersection,  or  the  vessel  herself  may  be  made 
to  complete  the  circuit  by  striking  a  circuit-closer. 

When  the  mines  are  placed  in  position,  accurate  bearings  of 
each  one  are  taken  from  two  secure  points  of  observation.  These 
stations  should  be  within  the  defensive  works,  and  selected  so 
that  the  lines  passing  from  them  over  each  mine  shall  intersect 
in  such  a  manner  as  to  give  as  nearly  as  possible  a  right  angle, 
or  at  least  an  angle  not  too  acute.  The  mines  have  each  a  num- 
ber, and  the  intersecting  lines  are  correspondingly  numbered; 
it  is  therefore  obvious  that  when  a  ship  is  observed  from  both 
stations  to  be  upon  a  line  having  the  same  number,  she  will  be 
at  the  intersection  of  the  two  lines,  or  over  the  mine  having  a 
like  number. 

The  simplest  form  is  where  one  of  the  stations  is  on  the  pro- 
longation of  the  line  of  mines,  as  at  A,  {Fig.  1,  Plate  75,)  and 
the  other  directly  in  rear  of  the  mines,  as  at  B.  C  represents 
the  galvanic  battery,  from  which  runs  a  conducting  wire  through 
the  station  A  to  station  B,  and  connects  at  the  latter  point  with 
a  series  of  keys,  through  which  the  current  can  be  closed  to  each 
of  the  mines  1,  2,  3,  <fcc.  Till  the  key  at  A  is  pressed  down,  no 
current  can  pass  from  the  battery  C  past  the  station  A;  bnt  dl- 


FIRING.  451 

rectly  it  is  pressed  down,  the  circuit  is  so  far  completed  and  the 
line  is  charged  up  to  the  station  B.  From  the  station  B  is  a 
series  of  electric  cables  (Bl,  B2,  B3,  &Q.)  attached  to  a  series  of 
contact  points,  perfectly  distinct  and  carefully  insulated  from 
each  other;  these  cables  pass  to  the  mines  (1,  2,  3,  &c.)  through 
the  fuses  in  connection  with  them  and  to  earth.  At  the  second 
station  B  we  have,  therefore,  a  second  break  in  the  electrical 
current,  and  it  is  easily  seen  that  in  order  to  pass  the  current 
through  and  fire  any  particular  fuse,  both  these  breaks  must  be 
bridged  over,  under  which  circumstances  the  current  of  the  bat- 
tery will  be  completed  and  the  mine  fired. 

Let  it  now  be  supposed  that  a  vessel  is  approaching  this  line 
of  mines.  As  her  bow  passes  across  the  prolongation  of  the  line 
B7  the  observer  at  B  puts  down  key  No.  7  in  connection  with 
mine  7 ;  but  as  the  ship  has  not  come  onto  the  line  from  A  pass- 
ing through  the  line  of  mines,  the  observer  at  A  does  not  put 
down  his  key,  a  break  still  exists  in  the  circuit,  and  no  current 
can  pass  to  fire  the  mine  7.  When  the  vessel  passes  the  line 
B7  the  observer  at  B  allows  the  key  to  spring  up  and  break  the 
connection.  As  the  vessel  passes  the  line  B6  the  observer  at 
B  presses  down  key  No.  6,  but  as  she  is  still  not  on  the  intersec- 
tion of  the  lines  B  6  and  A  6,  the  same  result  as  before  is  ob- 
tained, and  the  mine  6  will  not  be  fired.  Let  it  now  be  sup- 
posed that  she  passes  on  in  her  course  till  she  arrives  over  the 
mine  3;  in  this  position  she  is  on  the  intersection  of  the  two 
visual  lines  A  3  and  B  3 ;  the  observers  at  A  and  B  in  this  case 
both  put  down  their  respective  keys  simultaneously,  the  current 
of  the  battery  is  completed  through  the  mine  3,  and  that  mine 
will  be  fired. 

As  before  mentioned,  it  is  advantageous  to  have  the  lines  of 
mines  all  directed  on  one  point  (A).  The  mines  of  the  second 
and  third  lines  are  connected  to  the  station  B  precisely  as  are 
those  of  the  first  line.  In  the  case  of  a  vessel  passing  through 
an  interval  of  any  two  mines  of  the  first  line,  at  such  a  distance 
as  to  be  out  of  the  radius  of  destructive  eft'ect  of  either  of  them, 
as,  for  instance,  at  the  point  Y,  between  3  and  4,  it  is  easily  seen 
that  at  the  moment  of  passing  the  first  line  of  mines,  when  the 
observer  at  A  would  have  his  key  down,  she  would  not  be  on 
the  prolongation  of  any  of  the  visual  lines  from  the  station  B  to 
any  of  the  first  line  of  mines,  and  as  the  observer  at  B  would 
not  under  such  circumstances  press  down  any  key,  she  would 
pass  on  to  the  second  line  and  run  upon  the  mine  at  H,  which 
would  be  exploded  as  just  explained.  Instead  of  having  the 
wire  and  key  at  A,  as  above  explained,  an  ordinaiy  signal  flag 
may  be  used  for  transmitting  preconcerted  signals.    This,  how- 


452  FIRING. 

over,  would  require  the  observer  at  B  to  have  an  assistant  to 
look  out  for  the  flag,  and  is  altogether  inferior  to  the  former 
method.  It  likewise  has  the  disadvantage  of  informing  the 
enemy  of  the  position  of  the  lines  of  mines. 

As  in  many  cases  it  would  not  be  practicable  to  have  a  station 
on  such  a  position  as  A,  so  far  advanced  towards  the  point  of 
attack,  with  the  corresponding  danger  of  being  cut  off  by  an 
enemy,  another  combination  becomes  necessary ;  this  is  shown 
in  Fig.  2,  Plate  75. 

Two  stations,  A  and  B,  well  within  the  defensive  works,  are 
selected  in  such  a  position  that  the  lines  passing  from  them  over 
the  mines  shall  intersect  in  such  a  manner  as  to  give  a  large 
angle.  When  the  mines  were  placed  in  position,  accurate  bear- 
ings were  taken  to  each  from  both  of  these  stations.  The  gal- 
vanic battery  is  placed  at  A,  one  pole  being  connected  to  earth, 
while  the  other  is  connected  with  a  centre  from  which  radiate 
a  series  of  contact  keys.  From  the  contact  points  of  these 
keys  a  series  of  cables,  corresponding  in  number  to  the  numbers 
of  the  mines,  pass  to  the  similar  contact  points  of  a  like  set 
of  keys  at  station  B,  and  from  the  pivots  of  the  keys  at  B 
an  electrical  cable  passes  to  each  charge.  In  this  case,  there- 
fore, each  mine  has  a  separate  key  at  station  A  as  well  as  at 
station  B,  each  perfectly  distinct  from  any  other  and  well  in- 
sulated therefrom,  but  the  whole  culminating  at  A  in  the  single 
battery  C.  In  each  circuit,  corresponding  to  an}r  particular 
mine,  there  are,  therefore,  two  breaks,  one  at  its  particular  con- 
tact key  at  station  A,  and  the  other  at  its  corresponding  key  at 
station.  B,  and  till  these  breaks  are  bridged  over,  by  pressing 
down  the  contact  keys  simultaneously,  the  circuit  of  the  battery 
will  not  be  closed  and  the  mine  will  not  be  fired.  In  this  way 
it  is  easily  seen  that  if  key  No.  1,  for  example,  is  put  down  at 
station  A,  and  key  No.  2  at  station  B,  there  still  remains  a  break 
in  each  of  these  circuits;  in  circuit  No.  1  at  B  and  in  circuit  No. 
9  at  A,  and  neither  of  these  mines  will  be  fired.  The  object,  of 
*his  arrangement  is  seen  by  tracing  the  course  of  the  vessel  (X) 
approaching  the  line  of  mines.  She  first  arrives  on  the  line  of 
5  from  station  A  and  simultaneously  on  that  of  I  from  station  B; 
the  observer  at  A  puts  down  key  No.  5  and  the  observer  at  B 
key  No.  1,  without,  of  course,  firing  any  mine.  Again,  as  she 
reaches  the  position  Y,  the  observer  at  A  puts  down  key  No.  4 
and  the  observer  at  B  key  No.  2,  without  any  circuit  being  closed. 
When  she  arrives  at  3  both  observers  put  down  keys  No.  3  simul- 
taneously, and  the  mine  is  fired  and  the  vessel  struck. 

"In  carrying  out  the  system  above  described,  it  has  been 
found  that  with  a  series  of  very  small  wooden  pickets,  placed  in 


FIRING.  45$ 

3i  radiating  form  from  a  central  point  of  observation,  at  a  dis- 
tance of  about  20  feet,  and  with  pieces  of  twine  passing  from 
the  centre  over  the  pickets  in  the  direction  of  the  mines  to 
Indicate  the  bearings  more  accurately,  very  good  practice  has 
been  obtained.  The  observer,  with  his  eye  at  the  central  picket 
and  his  hand  on  the  contact  keys,  puts  the  corresponding  one 
down  as  the  object  passes  the  bearings  of  each.  A  man  soon 
learns  by  practice  the  distance  he  may  allow  on  one  side  or 
other  of  the  bearing  line,  and  with  ordinary  care  and  nerve  is 
soon  able  to  make  contact  at  the  right  moment. 

"  In  using  the  keys,  it  is  necessary  to  press  them  ftrmly  down 
and  hold  them  firmly,  in  order  to  insure  good  contact  at  the 
proper  moment. 

uTo  work  efficiently,  it  does  not  seem  desirable  that  more 
than  six  keys  should  be  intrusted  to  the  management  of  anyone 
man. 

"The  system  of  pickets  above  described  for  giving  the  bear- 
ings might  probably  be  used  effectually  up  to  half  a  mile,  but  at 
greater  distances  a  more  accurate  means  of  obtaining  the  inter- 
sections becomes  necessary;  the  pickets  have,  moreover,  the 
disadvantage  of  being  easily  disturbed  and  difficult  to  replace 
in  an  accurate  position  if  once  moved.  In  order  to  obviate  as 
far  as  possible  these  defects,  an  instrument  has  been  devised 
having  a  telescope,  with  cross-wires,  mounted  in  connection  with 
a  series  of  contact  points  and  a  movable  key,  as  shown  in  Fig.  3, 
Plate  75.  It  consists  of  a  heavy  cast-iron  stand  (a),  on  which  is 
placed  an  iron  upright  (6)  arranged  to  carry  the  telescope  (c), 
allowing  it  a  horizontal  motion  around  the  upright;  it  has  also 
a  vertical  motion.  Concentric  with  the  upright  is  a  circular  arc 
<rf),  described  with  a  radius  of  about  18  inches.  On  this  arc  are 
arranged  the  contact  points  for  the  cables  running  to  the  mines 
or  to  the  other  station.  Attached  to  the  upright,  below  the  tel- 
escope, is  a  horizontal  arm  (c),  which  moves  around  with  the 
telescope.  To  this  arm  is  attached  a  contact  key  ( /*),  adjusted 
to  touch  the  contact  points  on  the  arc.  The  arc  is  graduated 
into  divisions,  by  means  of  which  the  position  of  the  contact 
points  may  be  registered,  so  that  in  the  event  of  their  being 
accidentally  displaced  they  may  again  be  fixed  in  true  relative 
position  with  facility." 

To  place  the  instrument  in  position,  a  point  from  which  the 
lines  of  mines  are  clearly  distinguishable  should  be  chosen.  This 
point  should  be  as  far  as  possible  from  heavy  guns  and  have  a 
solid  foundation.  The  iron  stand  of  the  instrument  having  been 
leveled  by  means  of  leveling  screws,  the  telescope  is  directed  on 
some  fixed  and   well-defined  object,  and    the  number  of  the 


454  MECHANICAL   CIRCUIT-CLOSERS. 

division  under  the  spring  of  the  lever  registered.  The  telescope 
is  then  directed  on  each  buoy  marking  the  mines  of  each  line* 
in  succession,  and  one  of  the  contact  arrangements  brought 
into  proper  position  for  each  and  keyed  firmty  up,  and  the  num- 
ber of  the  mine  and  the  number  of  the  division  on  the  gradua- 
tion are  registered.  This  having  been  done  at  both  stations,  the 
buoys  marking  the  positions  of  the  mines  are  removed.  The 
points  where  the  leveling  screws  of  the  iron  stand  rest  should 
be  carefully  marked,  so  that  the  whole  may  be  placed  in  the 
same  position  if  accidentally  disturbed. 

The  observations  are  made  through  the  telescopes,  and  when  a 
vessel  comes  in  range  with  any  mine,  as  indicated  by  the  regis- 
tered degree,  the  corresponding  key  is  put  down,  the  operation 
being  in  every  other  respect  asbefore  described. 

691.  Mechanical  circuit- closers.  These  are  arrangements- 
by  which  submarine  mines  are  fired  electrically  by  the  vessel 
herself  closing  the  circuit. 

They  are  of  two  classes,  one  being  that  in  which  the  charge 
and  the  circuit-closer  are  in  the  same  case,  and  the  other  ia 
where  the  circuit-closer  is  in  a  separate  case,  but  connected  with 
the  charge  of  the  mine  by  an  electrical  cable.  In  botli  waysr 
the  conducting  cable  is  electrically  charged  from  the  battery  on, 
shore  up  to  the  circuit-closer ;  when  this  latter  is  closed  by  con- 
tact with  a  hostile  vessel,  the  current  passes  through  the  fuse  in- 
the  charge  and  the  mine  is  exploded.  A  great  number  of  differ- 
ent forms  of  both  classes  have  been  invented,  all  of  which  are 
more  or  less  complicated  and  require  special  description  and 
study  to  understand. 

To  render  mines  thus  provided  with  circuit-closers  harmless  to 
friendly  vessels  passing,  it  would  be  necessary  only  to  detach  the 
firing  battery — an  operation  usually  performed  by  the  operator 
simply  removing  a  small  plug.  In  this  case  the  circuit-closer,  if 
strongly  made,  may  be  struck  time  and  agaiu  without  injury. 
This  power  to  resist  heavy  blows  is  essential  to  the  efficiency  of  any 
form  of  circuit-closer,  as,  when  in  position  in  a  channel  through 
which  there  is  much  traffic,  they  are  always  liable  to  be  struck 
with  considerable  force  by  blades  of  screws,  floats  of  paddies, 
and  other  hard  and  sharp  bodies.  Another  especial  considera- 
tion is,  that  the  apparatus  for  closing  the  circuit  shall  not  be  set 
in  action  by  agitation  of  the  water,  but  only  by  impact  with  a 
floating  body.  The  circuit-closer  must  furthermore  have  suffi- 
cient size  to  give  the  required  amount  of  inertia.  When  the 
circuit-closer  and  charge  are  combined  in  the  same  case,  this  is 
assured  ;  but  when  the}r  are  separate,  it  is  effected  by  inclosing 
the  mechanism  in  buoys  made  of  wood  or  metal.    The  greater 


MECHANICAL   CIRCUIT-CLOSERS.  455 

the  size  and  weight  of  the  circuit-closer,  the  greater  will  be  the 
-chances  of  the  effective  working  of  the  apparatus. 

The  destructive  power  of  a  mine  decreases  rapidly  as  the  dis- 
tance from  it  increases.  The  circuit-closer  should  not,  there- 
fore, be  beyond  the  effective  range  of  the  mine.  Forty  to  fifty 
feet  should  be  the  maximum  distance  for  the  heaviest  charges. 

692*  The  arrangement  of  a  system  of  submarine  mines  in 
lines  possesses  the  disadvantage  that  if  the  enemy  has  once  as- 
certained the  position  of  one  mine  of  a  line,  whether  by  explo- 
sion or  by  any  accidental  circumstance,  he  would  know  within 
what  limits  the  others  were  to  be  looked  for.  In  order  to  obvi- 
ate this  disadvantage,  it  would  always  be  necessary  to  scatter  a 
few  mines  in  irregular  intervals  in  front  of  the  advanced  line — 
to  set  them  as  skirmishers,  retaining  the  line  formation  for  the 
main  defense.  These  advanced  mines  might  either  be  simply 
electro-self-acting,  or  arranged  for  ignition  on  the  same  principle 
as  those  of  the  main  system,  as  circumstances  required.  As  it  is 
not  advisable  to  expend  heavy  charges  against  small  boats,  these 
advanced  mines  should  be  comparatively  small,  so  as  to  be  used 
against  the  boats  of  an  enemy  seeking  for  the  mines  and  circuit- 
closers. 

"The  first  object  of  an  enemy  would  be  to  clear  a  passage  of 
sufficient  width  through  the  system  to  enable  him  to  pass  freely 
in ;  and  for  this  purpose  he  would  probably  employ  drifters, 
with  or  without  dragging  grapnels,  for  the  purpose  of  either 
tiring  some  of  the  charges  by  striking  the  circuit-closers,  or  grap- 
pling and  destroying  the  electrical  cables  and  other  gear.  These 
drifters  may  be  boats  allowed  to  float  in  with  the  tide  or  wind. 
Iu  order  to  stop  such  a  system  of  attack,  a  light  boom  or  strong 
-fishing-nets  would  be  useful,  and  should  be  employed  whenever 
circumstances  permit.  To  stop  drifters  with  dragging  grapnels, 
it  is  a  good  plan  to  lay  three  or  four  heavy  chain  cables  at  inter- 
vals across  the  channel,  in  advance  of  the  system  of  mines.  The 
grapnels  would  catch  in  these,  and  the  weight  of  the  chains 
would  be  sufficient  to  bring  up  the  drifters  before  arriving  at 
the  mines. 

"The  night  would  unquestionably  be  the  safest  time  for  the 
eaemy  to  carry  on  operations  of  this  nature,  and  it  would  be 
necessary  to  employ  boats  to  row  guard  in  order  to  watch  his 
proceedings.  The  mode  of  communication  with  these  boats  is 
a  matter  of  considerable  importance,  and  some  means  of  rapidly 
transmitting  intelligence  is  absolutely  necessary.  This  can.  of 
•course,  be  done  by  the  system  of  flashing  signals,  but  the  lights 
in  such  case  would  be  a  disadvantage,  as  they  would  indicate  to 
the  enemy  the  position  of  the  guard-boat.    In  order  to  obviate 


456  TESTING. 

this,  a  system  has  been  devised  by  which  a  boat  rowing  guard 
can  be  put  in  electrical  telegraphic  communication  with  a  fort  or 
guard-ship,  by  simply  paying  out  an  insulated  wire  attached  to- 
a  telegraph  instrument  in  the  fort  or  ship,  and  carrying  a  second 
instrument  on  board  the  boat.  Should  the  guard-boat  be  pursued, 
it  would  only  be  necessary  to  detach  the  electric  cable  from  the 
instrument  and  throw  it  overboard,  with  a  buoy  and  line  at- 
tached to  it,  and  pull  away. 

"Several  systems  have  been  devised  for  illuminating  chan- 
nels at  night  by  means  of  the  electric  light,  the  Drummond 
light,  magnesium  light,  <&c,  and  there  is  no  doubt  that,  when 
practicable,  such  devices  should  always  be  used." 

693*  Testing.  In  the  electrical-room  of  the  fort  are  kept 
the  instruments  for  testing  the  electrical  cables  of  the  mines,  for 
the  purpose  of  seeing  that  they  are  in  condition  to  perform  their 
work  efficiently.  The  most  essential  instruments  are  the  test- 
table  and  galvanometers.  With  these  the  cables  are,  from  time  to- 
time,  examined  to  ascertain  if  their  insulation  is  effective,  and 
if  they  have  a  sufficient  amount  of  electricity ;  if  the  firing  bat- 
tery is  in  a  condition  to  insure  certain  ignition ;  if  the  electrical 
connections  of  the  circuit-closers  are  correct;  if  the  electrical 
resistance  of  the  fuse  is  such  as  to  indicate  certainty  of  ignition, 
and  other  similar  information. 

A  separate  galvanometer  should  be  used  for  each  mine,  and 
a  special  battery,  distinct  from  the  firing  battery,  employed  in 
connection  with  the  testing  circuits ;  thus  obviating  the  necessity 
of  detaching  the  firing  battery  while  testing, — an  important  mat- 
ter likely  to  occur  at  the  critical  period  when  vessels  are  attempt- 
ing to  break  through  the  lines. 

Should  a  leak  be  discovered  in  a  cable,  the  extent  of  it  is  shown 
by  the  galvanometer ;  and  if  considerable,  the  defective  cable  is 
detached  from  the  battery  and  the  fault  repaired.  When  a  mine 
is  fired,  it  is  important  that  its  cable  should  be  disconnected  at 
once  from  the  firing  battery,  to  prevent  loss  of  power  through 
the  broken  end  of  the  conductor. 

When  a  separate  galvanometer  is  supplied  for  each  cable  of  a 
system  of  a  mines,  it  furnishes  a  constant  indicator  to  point  out 
the  fact  of  a  circuit-closer  being  struck  by  a  ship,  and  in  many 
cases  it  majrbe  convenient,  or  even  necessary,  to  perforin  the 
operation  of  throwing  in  the  firing  battery  without  the  aid  of  a 
personal  operator.  A  self-acting  apparatus  has  been  devised 
for  doing  it.  By  making  the  apparatus  purely  self-acting,  all 
chances  of  error  consequent  upon  the  inattention  or  want  of  dex- 
terity of  the  man  in  charge  is,  of  course,  eliminated.  No  mine 
or  circuit-closer  can  be  tampered  with  by  an  enemy  without  the 


TESTING.  457 

fact  being  instantly  known  in  the  testing-room,  and  precisely 
what  mine. 

As  it  is  of  importance  to  be  assured  of  the  condition  of  the 
charge  in  the  mine,  whether  dry  or  wet,  an  apparatus  for  thi9 
purpose  has  been  devised,  and  it  is  of  easy  application.  The  use 
of  it  obviates  the  necessity  of  the  great  labor,  time,  and  trouble 
that  would  be  required  to  raise  each  mine  and,  by  opening  it, 
ascertain  in  that  way  the  condition  of  the  charge. 

"  The  firing  battery  should  be  suited  to  the  nature  of  the  fuses 
employed,  and  should  possess  considerable  excess  of  power  in 
order  to  overcome  accidental  defects ;  such  as  increased  resist- 
ance in  the  communications,  or  defective  insulation  in  the  elec- 
tric cable  in  connection  with  the  mine.  A  battery  just  suffi- 
ciently powerful  to  fire  a  fuse  on  shore,  with  the  electric  cable, 
Ac,  in  circuit,  but  not  submerged,  would  not  be  unlikely  to  fail 
after  the  cable  lias  been  submerged  in  sea-water.  In  such  a  case 
it  is  recommended  that  the  battery  power  determined  by  such 
an  experiment  on  shore  be  doubled  for  actual  work.  For  all 
practical  purposes  this  test  can  be  made  by  firing  a  fuse  of  known 
quality  through  a  resistance  equivalent  to  that  of  the  cable. 
Double  the  number  of  cells  necessary  to  effect  this  would  be  re- 
quired for  the  submerged  cables,  Ac. 

4fc  When  a  system  of  mines  is  to  be  laid,  each  component  part 
should  be  tested  before  being  placed  in  position  and,  afterwards, 
as  the  parts  are  successively  combined  in  the  form  in  which  they 
are  to  be  used  before  submersion,  and  the  whole  should  again 
be  tested  immediately  after  submersion. 

uAsa  preliminary  to  all  electrical  testing,  it  is  necessary  to 
ascertain  if  the  instruments,  batteries,  &c,  used  in  making  the 
tests  are  themselves  in  good  working  order ;  otherwise  defects 
which  exist  in  the  testing  instruments  may  produce  results  which 
might  be  mistaken  for  defects  in  the  apparatus  under  trial." 

The  cases  are  tested  at  the  time  of  manufacture  to  ascertain 
if  they  are  thoroughly  water-tight  and  capable  of  bearing  the  ex- 
ternal pressure  to  the  extent  required,  according  to  the  depth  to 
which  they  are  to  be  submerged.  A  very  practical  test  for  this 
is  to  close  the  case  with  its  proper  mouth-piece  as  for  service, 
and  then  submerge  it  to  a  depth  somewhat  exceeding  that  at 
whicli  it  is  eventually  to  be  used.  After  remaining  thus  sub- 
merged for  about  forty-eight  hours,  it  is  lifted,  opened,  and  care- 
fully examined  to  see  that  it  has  remained  perfectly  dry  inside. 

A  careful  record  should  be  kept  of  the  results  of  all  electrical 
tests  applied,  as  by  preserving  the  electrical  history  of  any  com- 
bination a  defect  in  its  electrical  condition  may  be  readily  dis- 
covered, and  the  nature,  position,  and  extent  of  such  defect 
29  a 


458 


SURFACE  CURRENT  OF  HARBORS. 


indicated  with  a  considerable  degree  of  accuracy,  without  the 
necessity  of  raising  the  mine  out  of  water,  or  in  any  way  dia- 
turbing  the  arrangements  employed. 

The  foregoing  will  suggest  to  officers  charged  with  harbor 
defenses  the  capabilities  of  submarine  mines  as  an  auxiliary  to 
land  defenses.  It  also  furnishes  an  idea  of  the  kind  and  quan- 
tity of  material  required  for  establishing  a  system  of  mines,  and 
indicates  the  method  of  applying  and  using  it. 

Dexterity  in  the  use  of  testing  instruments — in  fact,  all  the 
electrical  manipulations  connected  with  submarine  mines — is  to 
be  acquired  only  by  practice,  with  the  aid  of  treatises  on  such 
subjects.  Experience  has  proved  that,  with  persons  of  good 
intelligence,  the  necessary  qualifications  may  be  acquired  in  a 
period  of  six  months. 

694*  The  following  table  gives  the  maximum  surface  current 
for  some  of  the  principal  harbors  upon  the  Atlantic  sea-board.  It 
will  be  useful  in  determining  the  kind  of  moorings  necessary  for 
securing  submarine  mines  in  these  channels : 


Locality, 


Portsmouth,  N.  H.,  In  the  channel  off  Fort  Constitution. 
Boston  Harbor,  Mass. : 

1.  Boston  Light-house  bearing  N.,  distant  H  mile ; 
depth  of  water  83  feet.....«~«....»».........w..»...~....... 

2.  Broad  Sound  Channel,  Long  Island  Light- 
house bearing  S.  by  W.,  distant  26  mile ;  depth 
of  water  68  feet. «• 

Entrance  to  Narragansett  Bay,  main  channel ~ 

New  York  Harbor,  Narrows ;  Fort  Lafayette  bearing 
N.  £.,  distant  M.  mile;  depth  of  water  90  feet ~~ 

Delaware  Bay,  in  the  channel  abreast  of  Brandywine 
Shoal.  (No  observations  were  made  near  Fort 
Delaware) 

Hampton  Roads,  Va.,  Old  Point  Comfort  Light-house 
bearing  N.  H  K,  distant  H  mile;  depth  of  water  78 
feet M 

Beaufort,  N.  C,  Fort  Macon  wharf  bearing  S.,  distant 
H  mile;  depth  of  water  26  feet ~ 

Cape  Fear  River,  west  entrance,  Fort  Caswell  bearing 
N.  W.,  distant  H  mile ;  depth  of  water  30  feet 

Winyah  Bay,  S.  C,  Georgetown  Light-house  bearing 
S.  E.,  distant  2  miles ;  depth  of  water  24  feet 

Charleston  Harbor,  Fort  Sumpter  bearing  W.,  distant 
%  mile ;  depth  of  water  29  feet » 

Savannah  River,  Ga.,  Tybee  Knoll  Light- vessel  bear- 
ing west,  distant  ?4  mile ;  depth  of  water  16  feet 

St.  Mary's  River,  Fla.,  Fort  Clinch  wharf  bearing  S., 
distant  X  mle;  depth  of  water  26  feet 


Maximum  ve- 
locity of  sur- 
face current 
in  miles  per 
hour. 


Ebb. 
1.00 

1.6 


Flow. 
1.5 

1.5 


1.1 

0.5 

1.1 
0.4 

1.9 

1.8 

1.4 

1.8 

1.7 

1.9 

2.8 

8.0 

1.4 

1.4 

2.4 

2.1 

2.5 

2.5 

1.4 

1.6 

9.1 

S.l 

tort  Siuttt. 


OUTLINES    OF    THE    GENERAL    PROPERTIES    OP 

PERMANENT  WORKS. 

Plate  77. 

The  term  permanent  fortification  belongs  to  that  branch  of  the 
<xri  of  fortification  whore  means  of  a  durable  character  are  used 
to  strengthen  a  position.  Permanent  differs  from  temporary 
fortification,  not  only  in  the  character  of  the  means  used,  but 
.also  in  offering  a  more  formidable  obstacle  to  the  enemy  from 
the  greater  strength  of  its  profile. 

Permaneut  works  may  be  divided  into  two  general  classes, 
fortresses  and  forts.  The  term  fortress  is  applied  to  fortified 
towns  alone,  and  the  term  fort  to  a  work  containing  only  a  gar- 
rison. 

The  character  of  the  fortification  is. the  same  in  both  classes, 
consisting  in  its  most  simple  form  of  an  elevated  and  wide  mound 
of  earth,  termed  the  rampart,  which  incloses  the  space  fortified; 
of  an  ordinary  parapet  surmounting  the  rampart,  and  of  a  wide 
and  deep  ditch  which  surrounds  the  whole. 

These  parts  of  the  profile  serve  the  same  purposes  as  the  cor- 
responding parts  in  the  profile  of  a  field-work;  the  most  striking 
difference  between  the  two  consists  in  the  rampart,  which,  from 
its  height,  gives  a  very  commanding  position  to  the  parapet,  and 
greatly  increases  the  obstacle  presented  to  the  enemy. 

To  give  both  strength  and  durability,  the  scarp  and  counter- 
scarp are  reveted  witli  walls  of  masonry  which  sustain  the  press- 
ure of  the  earth,  protect  it  from  the  effects  of  the  weather,  and 
by  their  height  and  steepness  present  an  insurmountable  obstacle 
to  an  assault  by  storm. 

A  fortification  thus  constituted  would  be  sufficient  for  the  pro- 
tection of  troops  within  it,  but  would  not  admit  of  exterior  oper- 
ations, because  it  affords  no  shelter  beyond  the  ditch.  There- 
fore, to  procure  the  facility  of  maneuvering  on  the  exterior,  a  low 
work,  in  the  form  of  a  glacis,  is  thrown  up  a  few  yards  in  front 
of  the  ditch,  and  completely  enveloping  it.    The  space  between 

(458a) 


458b  main  work. 

this  work  and  the  ditch  is  termed  the  covered-way,  because  it  \» 
covered  from  the  enemy's  view. 

The  simplest  form,  then,  of  an  effective  profile  for  permanent 
fortification,  consists  of  a  covered-way ;  a  wide  and  deep  ditch, 
with  a  scarp  and  counterscarp  of  masonry ;  and  a  rampart,  which, 
from  its  height  and  width,  will  give  a  commanding  position  to 
the  parapet,  and  sufficient  room  behind  the  parapet  for  the  nec- 
essary manoeuvres  of  the  troops  whilst  in  action. 

The  problem  presented  for  the  solution  of  the  engineer  con- 
sists in  making  such  a  disposition  of  his  works  that  no  point 
within  the  range  of  their  cannon  shall  afford  a  shelter  to  the  en- 
emy; that  they  shall  inclose  the  greatest  space  with  the  smallest 
perimeter,  without  sacrificing  the  reciprocal  protection  of  the 
parts,  afforded  by  a  Hanking  arrangement  within  the  medium 
range  of  arms ;  that  no  defensive  dispositions  which  can  be  de- 
stroyed by  the  enemy?s  distant  batteries,  shall  be  exposed  to 
their  fire ;  and  finally,  that  the  works  shall  be  secure  from  an 
attack  by  storm. 

To  satisfy  these  conditions,  the  space  to  be  occupied  must  nec- 
essarily be  inclosed  by  a  series  of  bastions  connected  by  curtains ; 
that  the  line  of  fortification  must  be  continuous,  and  consist  of 
a  wide  and  deep  ditch,  and  a  high  and  steep  scarp  of  masonry, 
to  be  perfectly  secure  from  an  escalade  ;  and  that  the  masonry 
of  the  scarp,  which  is  the  only  part  that  can  be  destroyed  by  a 
distant  fire,  must  be  covered  from  this  fire  by  the  glacis  of  the 
work  which  forms  the  covered-way. 

From  the  range  of  the  fire-arms  that  arc  used  in  the  defense, 
the  distance  between  the  salients  of  the  bastions  should  not 
exceed  six  hundred  yards,  and  that  for  a  reciprocal  flanking 
arrangement,  the  length  of  the  curtains  should  not  be  less  than 
twelve  times  the  absolute  relief.    (See  par.  611.) 

To  secure  the  work  from  escalade,  experience  has  fully  proved 
that  the  scarp  wall  should  not  be  less  than  thirty  feet  high,  and 
that  the  top  of  it  should  not  be  above  the  crest  of  the  glacis. 

The  width  of  the  terre-plein,  or  that  part  of  the  top  of  the 
rampart  behind  the  parapet,  is,  for  the  accommodation  of  mod- 
ern artillery,  about  thirty-five  feet,  and  its  height  should  give 
the  parapet  a  command  of  at  least  twenty  feet  over  the  exterior 
ground. 

The  dimensions  of  the  parapet  are  the  same  as  those  for  the 
profile  of  field-works  of  the  strongest  class.    (See  par.  596.) 

The  fortification  by  which  the  space  fortified  is  immediately 
enveloped,  is  termed  the  body  of  the  place,  or  the  enceinte.  It  is- 
seldom  that  a  permanent  work  consists,  simply  of  an  enceinte,, 
with  its  ditch  and  covered-way,  particularly  if  some  of  its  points 


outworks.  458c 

^re,  from  their  locality,  weaker  than  the  rest.  Other  works  are 
usually  added  to  strengthen  these  weak  points ;  they  are  termed 
outworks  when  they  are  enveloped  by  the  covered -way,  and 
detached  or  advanced  works  when  placed  beyond  it. 

The  object  of  these  works  is  to  lengthen  the  defense  by  forcing 
the  enemy  to  gain  possession  of  them  before  lie  is  able  to  make 
■a  breach  in  the  enceinte. 

The  principal  outwork  is  one  in  the  form  of  a  redan,  termed 
the  demilune*  which'  is  placed  in  front  of  the  curtain.  This 
work  adds  to  the  main  defense  by  a  cross-fire  on  the  bastion  sa- 
lients, which  are  the  weak  points  of  the  enceinte,  and  when  there 
are  demi-lunes  on  adjacent  curtains,  the  bastions  betweeu  them 
are  placed  in  strong  reenterings,  thereby  forcing  the  enemy  to 
gain  possession  of  the  demi-lunes  before  he  can  penetrate,  with- 
out great  labor  and  loss  of  life,  into  these  reenterings.  The  main 
■entrances  to  the  work  are  usually  through  the  curtains,  which, 
being  the  most  retired  parts,  are  also  the  most  secure ;  the  demi- 
lunes also  serve  to  cover  these  entrances,  and  to  guard  them  from 
a  surprise. 

The  ditch  of  the  demi-luue  is  sometimes  on  the  same  level  with 
the  main  ditch ;  sometimes  it  is  higher,  but  in  all  cases  the  com- 
munications between  the  two,  and  also  with  the  demi-lune  itself, 
are  arranged  so  as  to  be  easy  and  secure. 

Situated  between  the  two  flanks  of  the  bastions,  and  directly 
in  front  of  the  curtain,  a  small  low  work,  termed  the  tenaille* 
serves  to  mask  the  scarp-wall  of  the  curtain  and  flanks  from  the 
enemy's  batteries.  This  mask  is  of  very  great  importance,  since, 
by  preventing  the  enemy  from  making  a  breach  in  either  the 
flanks  or  curtain,  it  will  force  him  to  make  it  in  the  face  of  the 
bastion  ;  the  flanks  will  thus  be  preserved  for  the  defense  of  the 
breach,  and  the  enemy  will  not  be  able  to  turn  the  temporary 
or  permanent  works,  which  may  be  constructed  within  the  bas- 
tion to  prevent  him  from  gaining  possession  of  the  main  work, 
by  an  assault  of  the  breach,  which  he  would  be  able  to  do  could 
he  effect  a  breach  at  the  same  time  in  the  curtain  or  flanks. 

The  covered-ways  of  the  bastion  and  demi-lune  form  a  strong 
reentering  at  their  point  of  junction,  of  which  advantage  is  taken 
to  arrange  a  small  redan  whose  faces  flank  the  glacis  of  the  two 
covered-ways.  The  space  inclosed  b}r  this  work,  which  is  a  part 
of  the  covered- way  itself,  is  termed  the  reentering  place  of  arms. 

The  parts  of  the  covered-ways  in  front  of  the  salients  of  the 
bastion  and  demi-lune,  are  termed  the  salient  places  of  arms. 

The  places  of  arms  are  so  called  because  they  serve  for  the 
Assemblage  of  bodies  of  troops  who  are  to  act  on  the  exterior. 

Small  permanent  works,  termed  redoubts,  are  placed  within 


458d  communications. 

the  demi-lune,  and  the  reentering  place  of  arms,  for  the  purpose- 
of  strengthening  those  works. 

It  is  a  received  militar}'  principle,  that  the  garrison  of  a  work 
is  no  longer  in  safety,  when  it  can  be  carried  by  storm,  unless 
they  are  provided  with  a  secure  point  of  retreat.  It  is  to  effect 
this  purpose  that  redoubts  are  constructed.  The  one  in  the  re- 
entering place  of  arms  secures  the  cove  red- ways  from  an  attack 
by  storm  ;  and  that  in  the  demi-lune  forces  phe  enemy  to  advance 
gradually,  and  with  the  greatest  precaution,  to  gain  possession 
of  the  breach  in  the  demi-lune ;  and  being  provided  with  flanks, 
which,  from  their  position,  have  a  reverse  fire  on  the  breach  in 
the  bastion  face,  the  enemy  is  forced  to  make  himself  master  of 
it  before  he  can  venture  to  assault  the  breach  in  the  bastion. 

Works,  termed  interior  retrenchments,  which  have  the  same 
properties  as  a  redoubt,  are  constructed  within  the  bastion. 
When  the  interior  retrenchment  is  sufficiently  elevated  to  com- 
mand the  exterior  ground,  it  is  termed  a  cavalier. 

The  protection  afforded  by  a  redoubt  to  another  work,  is  not  . 
by  offering  a  place  of  safety  into  which  the  garrison  of  the  work 
can  retire  when  driven  out  of  it,  but  in  covering  the  retreat  of 
the  garrison  by  a  warm  fire,  which  will  check  the  advance  of  the 
enemy,  and  enable  it  to  retire  behind  the  redoubt,  and  there  re- 
form to  resist  further  advance  of  the  eneni3r  into  the  works. 

The  crest  of  the  glacis  is  broken  into  an  indented  line  for  the 
purpose  of  obtaining  a  flank  and  cross  fire  on  the  ground  in  front 
of  the  places  of  arms. 

Traverses  are  placed  at  intervals  along  the  covered-ways ;  they 
serve  to  intercept  the  projectiles  which  enfilade  the  covered-ways, 
and  also  to  defend  them  foot  by  foot,  enabling  the  troops  to  re- 
treat from  one  part  of  the  covered-way  behind  the  traverse  under 
the  protection  of  its  fire. 

The  principal  communications  consist  of  ramps,  stairs,  pos- 
terns, gateways,  bridges,  and,  for  wet  ditches,  sometimes  dikes. 

Ramps  for  the  use  of  artillery,  or  other  vehicles,  have  a  width 
on  top  of  10  to  15  feet,  and  an  inclination  from  £  to  ^ 

Stairs,  except  for  temporary  purposes,  are  constructed  of  stone, 
and  are  usually  placed  along  the  counterscarp  and  gorge  walls 
of  the  outworks,  forming  a  communication  for  infantry  only, 
between  the  ditch  and  the  terre-plein  of  the  work  to  which  they 
lead.  They  are  also  used  within  the  enceinte  in  positions  where 
there  is  not  sufficient  room  for  ramps. 

Posterns  are  arched  bomb-proof  passage-ways,  constructed  un- 
der the  ramparts,  forming  communications  between  the  parade 
and  the  main  ditch,  or  between  the  ditches  and  the  interior  ot 
the  outworks. 


BRIDGES.  458E 

For  artillery,  the  width  is  usually  10  feet  and  the  height  8  feet. 
For  infantry,  these  dimensions  may  be  much  less.  A  strong 
wooden  door  is  placed  at  each  end  of  the  postern.  These  doors 
should  be  loop-holed  for  musketry. 

Gateways.  In  works  with  large  garrisons,  where  the  means 
of  frequent  communications  with  the  exterior  are  required,  pos- 
terns are  constructed  of  sufficient  width  to  admit  of  at  least  a 
single  carriage-mad  with  a  narrow  foot-path  on  each  side. 

An  arched  chamber  is  generally  placed  on  one  side  of  the  pos- 
tern, and  the  wall  between  is  loop-holed,  so  as  to  secure  a  mus- 
ketry tire  on  the  doorway  of  the  postern.  The  arched  chamber 
serves  as  a  guard-room.  As  a  further  precaution  against  sur- 
prise, a  machicoulis  defense  is  sometimes  arranged  at  the  top 
of  the  scarp-wall  just  above  the  doorway  of  the  postern. 

Bridges.  The  communication  across  the  main  ditch  leading 
from  the  gateway  to  the  country  is  usually  an  ordinary  wooden 
bridge.  The  bay  of  this  bridge  at  the  gate  is  spanned  by  a  draw- 
bridge of  timber,  which,  when  drawn  up,  closes  and  secures  the 
gateway.  A  barrier,  termed  a  portcullis,  which  can  be  lowered 
or  raised  vertically  by  machinery,  is  sometimes  added  to  secure 
the  passage-way  from  surprise. 

In  recent  works,  the  portcullis,  and  even  the  doors  preceding 
them,  have  been  constructed  of  a  strong  lattice-work  of  wrought- 
iron  bars.  This  is  a  great  improvement,  both  as  to  durability 
and  defense.  All  passage-ways  should  be  placed  in  the  most 
secure  part  of  the  works,  and  under  such  flanking  arrangements 
as  to  cover  them  with  close  musketry  fire,  or  with  that  from 
machine  guns. 

With  regard  to  the  relief  of  the  outworks,  as  a  general  princi- 
ple those  most  advanced  should  be  commanded  by  those  most 
retired.  This  principle  is  applied  in  all  the  works,  except  the 
tenaille  and  the  redoubt  of  the  reentering  place  of  arms.  The 
former  must,  not  mask  the  fire  of  the  bastion  flanks  along  the 
main  ditch,  and  the  latter  must  not  mask  the  fire  of  the  bastion 
faces  upon  the  glacis  of  the  demi-lune  covered-way.  To  satisfy 
these  conditions,  the  two  works  must  be  commanded  by  the  demi- 
lune, which  is  more  advanced  than  either  of  them ;  but,  by  the 
process  of  defilement,  they  are  both  so  arranged  that  the  enemy 
will  not  have  a  plunging  fire  into  them  from  the  demi-lune. 

All  the  fortification  comprehended  between  the  capitals  of  two 
adjacent  bastions  and  the  glacis,  is  termed  a  front  of  foriijica- 
tion%  or  simply  a  front.  It  is  taken  as  the  unit  in  permanent 
fortification. 

The  usual  method  of  effectually  protecting  anjf  point,  is  by  a 
flank  fire ;  but,  owing  to  the  locality,  or  to  some  other  cause,  it 


458f  casemates. 

may  not  be  practicable  to  make  a  flanking  arrangement.  To" 
supply  its  place,  dispositions,  termed  counterscarp  galleries^  are 
made  behind  the  counterscarp,  with  loop-hole  defenses  for  a 
reverse  fire.  This  arrangement  approximates  the  nearest  to  the 
military  solution  of  the  problem  to  see  without  being  seen*  since, 
from  the  position  of  these  galleries,  the  enemy  will  not  be  able 
to  bring  his  batteries  to  bear  on  them,  whilst  they  will  present 
a  formidable  impediment  to  all  of  his  operations  in  the  ditches. 

For  sea-coast  defenses,  embrasures  are  made  through  the  scarp- 
wall,  and  the  artillery  is  protected  from  shells  by  an  arched 
bomb-proof  covering  overhead.  This  arrangement  is  termed  a 
defensive  casemate.  This  method  of  defense  is  only  efficacious 
against  a  sea  attack;  for  on  the  land  side,  where  the  enemy  can 
approach  regularly,  casemates  would  be  rapidly  destroyed  by  his 
batteries,  and  the  loss  of  life  would  be  far  greater  in  them  than 
in  an  open  defense,  owing  to  the  fragments  of  stone  which  each 
shot  striking  an  embrasure  would  cause. 

The  arch  of  the  casemate  is  supported  by  piers  extending  back 
from  the  scarp-wall.  These  piers  are  usually  about  six  and  a 
half  feet  thick,  and,  a  few  feet  back  from  the  scarp-wall,  are 
pierced  by  arched  passage-ways,  which,  besides  securing  free 
communication  from  one  casemate  to  another,  gives  the  gun- 
carriage  a  wider  traverse  by  allowing  the  rear  end  to  run  under 
this  opening. 

The  arches  of  the  casemates  are  of  brick,  and  have  a  thickness 
of  three  feet  exclusive  of  the  roof-shaped  capping,  which  is  gen- 
erally of  rubble  and  b^ton,  and  covered  on  top  by  the  earth  of 
the  rampart  and  parapet.  At  least  six  feet  of  earth  is  necessary 
to  give  full  security  against  shells. 

Arched  recesses  are  made  in  the  scarp-wall  at  the  embrasure 
to  permit  the  gun  being  well  run  out  to  prevent  the  smoke  from 
entering  the  casemate. 

The  embrasure  is  in  the  centre  of  the  recess,  the  sole  being  at 
the  proper  height  for  the  easy  service  of  the  piece. 

In  some  casemates,  flues  for  ventilation  and  carrying  off"  rapidly 
the  smoke  of  discharge  run  from  the  top  of  the  carriage  recess 
through  the  masonry  of  the  scarp-wall,  and  have  their  outlet  in 
the  top  of  the  wall  outside.  In  others,  the  flues  run  from  the 
casemate  arch  to  the  top  of  the  scarp-wall. 

Beneath  the  embrasure,  a  recess,  termed  the  tongue-hole,  is 
made  to  receive  the  tongue  of  the  chassis.  The  tongue  is  con- 
lined  in  its  place,  and  the  chassis  traversed  around  a  pintle, 
which  is  received  into  the  pintle-hole  made  at  the  centre  point  of 
the  throat  of  the  embrasure,  and  extending  into  the  masonry 
below  the  tongue-hole.    When  the  casemate  serves  also  as  quar- 


MAGAZINES.  4580 

ters  for  the  garrison,  the  rear,  toward*  the  parade,  is  closed  by  a 
masonry  wall,  which  forms  the  front  of  the  quarters.  A  brick 
partition  wall  separates  the  quarters  from  ihe  qun-room. 

Built  up  with  this  wall  are  tire-places,  with  flues  extending  to 
the  parapet  above. 

The  front  or  parade  end  of  the  quarters  is  suitably  finished, 
with  doors  and  windows. 

In  contracted  situations,  where  it  is  desirable  to  secure  greater 
fire  in  a  fixed  direction  than  can  be  had  from  a  single  tier  of 
casemates,  one  or  more  tiers  are  added,  the  parapet  being  re- 
tained as  before.  The  arches  of  the  top  tier  are  alone  bomb- 
proof; those  of  the  lower  tiers  being  of  sufficient  strength  to  re- 
ceive the  armament  and  admit  of  the  service  of  the  guns  with 
safety. 

Mortars  being  placed  behind  the  ramparts  or  traverses  to  secure 
them  against  horizontal  fire,  are  protected  from  vertical  fire  by 
arches  covered  with  earth,  as  in  the  preceding  case.  The  arch 
rises  towards  the  front  to  give  room  for  the  shell  in  its  flight. 
The  front  end  of  the  casemate  is  walled  up  to  a  height  of  about 
six  feet.  This  permits  the  mortar  to  be  fired  over  the  wall,  and 
the  interior  of  the  casemate  is  protected  to  a  great  degree  from 
falling  shells  and  splinters. 

Casemates  are  also  used  simply  as  bomb-proof  shelters  for  the 
troops  and  material.  These  may  be  constructed  in  the  ramparts 
of  land  fronts,  where  guns  are  used  onl}r  in  barbette. 

Upon  land  fronts,  where  it  is  important  to  have  the  masonry 
covered  by  earth  from  the  fire  of  stationary  batteries,  embrasures 
are  made  in  the  parapet,  after  the  manner  prescribed  in  par.  634. 
The  arch  of  the  casemate  is  united  to  the  interior  slope-wall,  as, 
in  the  preceding  case,  it  was  to  the  scarp-wall.  Its  covering  of 
earth  extends  down  in  front,  forming  the  merlons  of  the  parapet, 
thus  covering  all  the  masonry  except  that  of  the  embrasure. 
The  front  portion  of  the  arch  of  the  casemate  is  conoidal,  and 
descends  down  to  the  top  of  the  embrasure. 

Magazines  (see  pars.  569,  637)  for  permanent  works  are  con- 
structed usuully  in  connection  with  the  enceinte,  being  placed  in 
the  most  secure  part  of  the  work.  They  are  built  with  strong, 
full  centre  bomb-proof  brick  arches,  supported  on  heavy  masonry 
piers,  which  form  the  outward  walls.  The  arches  are  covered 
with  not  less  than  eight  feet  of  earth. 

The  interior  of  the  magazine,  the  floors,  and  the  doors  and 
windows  are  built  with  a  view  to  security  from  fire,  and  to  pre- 
serve the  powder  from  dampness  by  a  good  system  of  drainage 
around  the  foundations,  and  of  ventilation  by  means  of  air-holes 


458h  detached  works. 

made  through  the  piers  and  panels  of  copper  pierced  with  smalF 
holes  placed  in  the  doors. 

No  iron  or  steel  is  allowed  in  any  part  of  the  structure,  bronze 
being  used  where  it  is  necessary  to  employ  metal. 

The  exterior  openings  for  air-holes  are  covered  with  copper 
mesh-work  to  prevent  combustible  material  or  rats  or  mice  pene- 
trating to  the  interior  of  the  magazine. 

Heavy  guns  are  usually  placed  in  pairs,  with  a  traverse  be- 
tween each  set  of  pairs.  In  this  traverse  is  built  the  service 
magazine  for  the  adjacent  pieces. 

Advanced  works  are  those  placed  beyond  the  outworks,  and 
are  so  under  the  fire  of  either  the  main  work  or  the  outworks  as 
to  have  the  ground  in  advance  of  them  swept  by  this  fir; ;  their 
ditches  flanked  by  it,  and  their  interior  so  exposed  to  it,  that  if 
the  work  were  seized  by  the  enemy  he  could  be  driven  from  it 
by  this  fire. 

Detached  works  are  those  which,  although  having  an  important 
bearing  on  the  defense  of  the  main  work,  are  so  far  from  it  as  to 
have  to  depend  solely  on  their  own  strength  in  case  of  assault. 

Explanations  op  Plate  77. 

Plan  of  a  regularly  fortified  front : 

A  A  .  .  A  is  the  enceinte,  or  body  of  the  place. 

BB,  the  bastions. 

CC  .  .  C,  the  main  ditch,  or  ditch  of  the  enceinte. 

DD  .  .  D,  the  bastion  and  demi-lune  covered-ways. 

EE,  the  reentering  places  of  arms. 

fff,  the  salient  places  of  arms. 

G,  the  demi-lune. 

H,  the  demi-lune  ditch. 

J,  the  demi-lune  redoubt. 

ll,  the  ditch  of  the  demi-lune  redoubt. 

MM,  the  redoubts  of  the  reentering  places  of  arms. 

a  a  .  .  «,  traverses  of  the  covered-way. 

o,  tiic  tenaille. 

Fig.  A  shows  a  section  of  the  enceinte,  main  ditch,  and  cov- 
ered-way. 

A  is  the  rampart;  of  which  ab  is  the  slope,  and  be  the 

terre-plein. 
B  is  the  parapet;  of  which  cdegh  is  the  outline. 
G  is  the  main  ditch. 

D,  the  scarp  wall. 

E,  the  counterscarp  wall. 

F,  the  embankment  of  the  covered-way;  of  which  mn  is 

the  terre-plein,  n  op  the  outline  of   the  banquette* 
interior  slope,  and  glacis. 


gart  ttb  tmrtfc. 


SALUTES  AND  CEREMONIES. 

This  subject  is  introduced  under  the  following  authority : 

Navy  Department,  Washington,  Nov.  20,  1879. 
Sir  :  Referring  to  your  letter  of  the  30th  ultimo,  transmitting  the  manu- 
script of  a 4I  Chapter  on  Artillery  Salutes  in  General,"  by  Major  Tidball,. 
of  the  United  States  Army,  I  have  the  honor  to  inform  yon  that  the  officer* 
of  the  Navy  to  whom  it  was  submitted  report  that  it  conforms  to  naval 
usage  and  the  conventions  with  foreign  powers  with  respect  to  the  etiquette 
of  visits  and  salutes. 
The  manuscript  is  herewith  returned. 

Very  respectfully, 
(Signed)  R.  W.  THOMPSON, 

Secretary  of  the  Nary. 
Hon.  O-kobgk  W.  McOrary,  Secretary  of  War. 

Approved : 

By  order  of  the  Secretary  of  War. 
(Signed) 


War  Department,  Nov.  20,  1879. 


JOHN  TWEEDALE, 

Acting  Chief  Clerk. 


695.  A  salute  with  camion  is  a  certain  number  of  guns  fired 
In  succession  with  blank  cartridges,  in  honor  of  a  person,  to- 
celebrate  an  event,  or  to  show  respect  to  the  flag  of  a  country. 

The  rapidity  with  which  the  pieces  are  discharged  depends 
upon  their  calibre.  Field  guns  should  have  intervals  of  five 
seconds  between  discharges;  siege  guns,  eight;  and  guns  of 
heavier  calibre,  ten. 

The  minimum  number  of  pieces  with  which  salutes  can  be 
fired  is  two  for  field,  four  for  siege,  and  six  for  sea-coast  guns. 

Mortars,  as  a  rule,  are  not  used  for  saluting  purposes. 

696.  Personages  entitled  to  salutes,  if  passing  a  military 
post,  as  also  foreign  ships-of-war,  are  saluted  with  guns  of  heavy 
calibre,  the  most  suitable  being  the  10-inch  smooth-bore. 

When  troops  are  drawn  up  for  the  reception  of  a  dignitary, 
and  it  is  practicable  to  have  a  battery  of  field  guns  on  the 
ground,  a  salute  from  it  should  form  part  of  the  ceremony;, 
otherwise  guns  in  position  are  used. 

The  national  salute,  and  minute-guns  upon  funeral  occasions,, 
are,  when  practicable,  fired  from  heavy  pieces. 

(459) 


460  SALUTES   AND   CEREMONIES. 

69*7.  The  pieces  used  for  a  salute  should,  if  possible,  be  of 
the  same  or  equivalent  calibre ;  and  when  the  number  on  the 
front  of  a  work  admits  of  it,  the  entire  number  required,  and 
two  or  three  over,  should  be  loaded  and  made  ready  previous  to 
•commencing  the  salute;  the  detachments  are  then  dispensed 
with,  and  a  single  cannoneer  at  each  piece  discharges  it  at  the 
proper  time.  When  the  number  of  pieces  is  insufficient  for  the 
entire  salute,  as  many  as  possible  should  be  used,  so  as  to  avoid 
frequent  reloadings. 

698.  The  pieces  are  numbered  from  light  to  left, — one,  two, 
three,  and  so  on, — and  each  detachment  or  the  cannoneer,  as 
the  case  may  be,  is  made  to  clearly  understand  the  number  of 
the  piece.  To  insure  regularity  of  intervals,  the  officer  in  charge 
of  the  firing  should  habituate  himself  to  uniformity  in  giving  the 
-commands  to  fire. 

At  the  proper  moment  the  officer  in  charge  commands :  Num- 
ber one,  Fire,  and  observing  the  proper  interval,  Number  two, 
Fire,  and  so  on  to  the  left  piece,  when  he  returns  to  the  first 
and  repeats  the  same  commands  until  the  entire  number  re- 
quired  for  the  salute  is  discharged.  In  order  to  preserve  regu- 
larity in  the  fires,  he  will  not  concern  himself  with  the  running 
number,  but  will  have  a  capable  person  to  keep  the  count  and 
notify  him  when  the  required  number  of  discharges  are  made. 
In  giving  the  command  fire,  he  looks  towards  the  piece  to  be 
fired,  and  gives  it  in  such  a  pronounced  manner,  accompanied 
by  a  signal  with  his  sword,  as  to  be  unmistakable;  the  can- 
noneer discharging  a  piece,  when  its  number  is  called  casts  his 
eyes  to  the  officer,  and,  observing  the  signal  as  well  as  the  com- 
mand, pulls  the  lanyard  with  promptness  and  decision.  The 
officer  will  be  careful  to  avoid  excitement  iu  himself  or  to  cause 
it  in  the  men  firing  the  pieces.  Should  a  piece  miss  fire,  he 
immediately  commands  the  next  to  fire,  and  allows  the  piece 
that  has  missed  to  remain  undischarged  until  its  proper  turn 
.again  comes.  Immediately  after  each  piece  is  discharged  it  is 
reloaded  and  made  ready.  The  cartridges  are  withdrawn  from 
the  pieces  that  remain  loaded  at  the  conclusion  of  the  salute. 

699.  Salvos  are  simultaneous  discharges  from  several  can* 
jton.  They  correspond  to  volleys  of  musketry,  and  are  fired, 
by  vvay  of  salute,  only  over  the  graves  of  officers  at  the  time  of 
burial. 

The  order  designating  a  funeral  escort  prescribes  whether 
the  fire  shall  be  three  volleys  of  musketry  or  three  salvos  of 
artillery. 

The  following  are  prescribed  salutes : 


national  and  personal  salutes.  401 

National  Salutes. 

TOO*  The  national  salute  is  one  gun  for  each  State  in  the- 
Union. 

The  international  salute,  or  the  salute  to  a  national  flag,  is 
21  guns. 

Personal  Salutes. 

701*   To  civil  and  diplomatic  authorities. 

The  President  of  the  United  States  receives  a  salute, 
to  be  given  both  on  his  arrival  at  and  final  departure 
from  a  military  post  or  station  provided  with  artil- 
lery, of 21  guns. 

The  Vice-President  of  the  United  States 19  guns^ 

Members  of  the  Cabinet,  the  Chief  Justice,  the  Speaker 
of  the  House  of  Representatives,  the  Governors  with- 
in their  respective  States  or  Territories 17  gnus- 

A  committee  of  Congress  officially  visiting  a  military 
post  or  station 17  gnns. 

The  Sovereign  or  Chief  Magistrate  of  a  foreign  State,  to 
be  given  both  on  arrival  at  and  final  departure  from 
a  military  post  or  station  provided  with  artillery 21  guns. 

Members  of  the  Royal  Family,  t.  c,  the  Heir-apparent 
and  Consort  of  the  reigning  sovereign  of  a  foreign 
State 21  guns. 

The  Viceroy,  Governor-General,  or  Governors  of  prov- 
inces belonging  to  foreign  States 17  guns^ 

Ambassadors  Extraordinary  and  Plenipotentiary 17  guns. 

Envoys  Extraordinary  and  Ministers  Plenipotentiary..  15  guns. 

Ministers  Resident  accredited  to  the  United  States 13  guns. 

Charges  d'  Affaires,  or  subordinate  diplomatic  agents 
left  in  charge  of  missions  in  the  United  States 11  guns. 

Consuls-General  accredited  to  the  United  States 9  guns. 

702.    To  military  and  naval  officers. 

The  General-in-Chief,  Field  Marshal,  or  Admiral 17  guns~ 

Lieutenant-General  or  Vice- Admiral 15  guns. 

Major-General  or  Rear- Admiral 13  guns. 

Brigadier-General  or  Commodore 11  guns. 

Officers  of  volunteers  and  militia,  only  when  in  the  service  of 
the  United  States,  the  salute  specified  for  their  rank. 

Officers  of  foreign  services  visiting  any  military  post  or  station 
provided  with  artillery,  are  saluted  in  accordance  with  their 
rank. 


462  NATIONAL   AND   INTERNATIONAL   SALUTES. 

In  addition  to  the  foregoing,  occasions  of  a  public  nature 
frequently  arise  when  salutes  are  both  desirable  and  proper. 
Orders  will  govern  in  such  cases.  Personal  salutes  are,  however, 
strictly  confined  to  the  foregoing,  and  are  fired  but  once,  unless 
otherwise  specified  herein. 

703.  Salutes  are  fired  only  between  sunrise  and  sunset,  aud, 
41s  a  rule,  never  on  Sunday. 

The  national  color  must  always  be  displayed  at  the  time  of 
firing  salutes. 

The  national  salute  is  fired  at  noon  on  the  anniversary  of  the 
Independence  of  the  United  States  at  each  military  post  or  camp 
provided  with  artillery. 

704.  The  international  salute  is  the  only  salute  which  is  re- 
turned, and  this  is  invariably  done  as  soon  as  possible.  The 
time  intervening  must  never  exceed  twenty-four  hours.  The 
failure  to  return  such  salute  is  regarded  as  a  discourtesy  or  lack 
of  friendship  justifying  the  other  partjr  in  asking  explanation. 

In  the  presence  of  the  President  of  the  United  States,  however, 
no  salute,  other  than  the  national  salute,  and  that  specified  for 
hirn,  is  to  be  fired. 

705.  It  is  the  custom  for  saluting  vessels-of-war  upon  anchor- 
ing in  presence  of  a  fort,  to  hoist  at  the  fore  the  flag  of  the  coun- 
try in  whose  waters  they  are,  aud  to  fire  the  first  salute.  A 
failure  to  do  so  is  a  proper  subject  for  explanation. 

Notice  of  an  intention  to  salute  the  flag  is  usually  given  by 
the  vessel  direct  to  the  fort ;  but  as  giving  notice  involves  delay, 
vessels  frequently  salute  without  it.  Vessels  mounting  less  than 
ten  guns  do  not  fire  salutes  requiring  the  guns  to  be  reloaded. 
Surveying  vessels,  store-ships,  or  transports  do  not  salute. 

If  there  be  several  forts  or  batteries  in  sight,  or  within  six 
miles  of  each  other,  oue  of  them  is  designated  in  orders  to  return 
international  salutes.  Either  of  the  others  receiving  notice  from 
a  saluting  vessel  of  intention  to  salute  the  flag,  immediately  no- 
tifies the  one  designated  as  the  saluting  fort,  and  informs  the 
vessel  of  the  fact.  If  a  vessel  salutes  without  giving  notice,  the 
fort  designated  as  the  saluting  fort  returns  it. 

United  States  vessels  return  salutes  to  the  flag  in  United  States 
waters,  only  where  there  is  no  fort  or  battery  to  do  so. 

United  States  vessels  do  not  salute  United  States  forts  or  posts. 

Salutes  to  the  flag  are  in  no  sense  to  be  considered  as  personal. 

706.  The  President  of  the  United  States,  the  Sovereign  or 
Chief  Magistrate  of  a  foreign  country  traveling  in  a  public  ca- 
pacity, is  saluted  when  passing  in  the  vicinity  of  a  military  post. 

A  vessel-of-war  on  which  the  President  of  the  United  States  1b 
traveling  displays  the  national  ensign  at  the  main.    In  the  case 


OFFICIAL  COURTESIES.  468 

of  foreign  sovereigns,  vessels  display  the  royal  standard  of  the 
-sovereign  in  like  manner. 

TOT.  Personal  salutes,  in  compliment  to  foreign  diplomatic 
^authorities,  are  to  be  fired  only  for  those  whose  nations  pay  the 
same  compliments  to  United  States  diplomatic  ministers  in  their 
territories. 

Personal  salutes  at  the  same  place  and  in  compliment  to  the 
same  person,  whether  civil,  diplomatic,  military,  or  naval,  are 
never  to  be  fired  oftener  than  once  in  twelve  months,  unless  such 
person  shall  have  been,  in  the  meantime,  advanced  in  rank. 

Officers  on  the  retired  list,  whether  military  or  naval,  are  not 
to  be  saluted.  This,  however,  does  not  apply  to  funeral  cere- 
monies. 

An  officer,  whether  civil,  military,  or  naval,  holding  two  or 
more  positions,  either  of  which  entitles  him  to  a  salute,  receives 
•only  the  salute  due  to  the  highest  grade.  In  no  event  is  the 
flame  person  to  be  sainted  in  more  than  one  capacity. 

When  several  persons,  each  of  whom  is  entitled  to  a  salute,  ar- 
rive together  at  a  post,  the  one  highest  in  rank  or  position  is  alone 
saluted.    If  they  arrive  successively,  each  Is  saluted  in  turn. 

An  officer  assigned  to  duty  according  to  brevet  rank  receives 
the  salute  due  to  the  full  rank  of  the  grade  to  which  he  has  been 
assigned. 

As  a  rule,  a  personal  salute  is  to  be  fired  when  the  personage 
entitled  to  it  enters  the  post. 

When  the  troops  at  a  military  post  are  to  be  reviewed  by  a  per- 
sonage entitled  to  a  salute,  it  is  most  appropriate  to  fire  the  salute 
from  field  guns  at  the  place  of  review,  and  at  the  time.  Just  pre- 
vious to  the  review,  when  the  personage  arrives  on  the  ground. 

Official  Courtesies. 

T08*  The  interchange  of  official  compliments  and  visits  be- 
tween foreign  military  or  naval  officers,  and  the  authorities  of  a 
military  post,  are  international  in  character. 

In  all  cases  it  is  the  duty  of  the  commandant  of  a  military  post, 
without  regard  to  his  rank,  to  send  a  suitable  officer  to  offer  civ- 
ilities and  assistance  to  a  vessel-of-war  (foreign  or  otherwise) 
recently  arrived. 

After  such  offer  it  is  the  duty  of  the  commanding  officer  of  the 
vessel  to  send  a  suitable  officer  to  acknowledge  such  civilities, 
and  request  that  a  time  be  specified  for  his  reception  by  the 
commanding  officer  of  the  post. 

The  commanding  officer  of  a  military  post,  after  the  usual 
offer  of -civilities,  is  always  to  receive  the  first  visit  without  re- 
gard to  rank.    The  return  visit  by  the  commanding  officer  of 


464  OFFICIAL   COURTESIES. 

the  military  post  is  made  the  following  day,  or  as  soon  thereafter 
as  practicable. 

709.  When  a  military  commander  officially  visits  a  vessel-of- 
war  he  gives  notice  of  his  visit  to  the  vessel  previously  thereto,  or 
sends  a  suitable  officer  (or  an  orderly)  to  the  gangway  to  an- 
nounce his  presence,  if  such  notice  has  not  been  given-.  He  is 
then  received  at  the  gangway  by  the  commander  of  the  vessel, 
and  is  accompanied  there  on  leaving  by  the  same  officer.  The 
officer  who  is  sent  with  the  customary  offer  of  civilities  is  met 
at  the  gangway  of  a  vessel-of-war  by  the  officer-of-the-deck; 
through  the  latter  he  is  presented  to  the  commander  of  the  ves- 
sel, with  whom  it  is  his  duty  to  communicate. 

A  vessel-of-war  is  approached  and  boarded  by  commissioned 
officers,  by  the  starboard  side  and  gangway,  when  there  are  gang- 
ways on  each  side. 

In  entering  a  boat,  the  junior  goes  first  and  other  officers 
according  to  rank;  in  leaving  a  boat,  the  senior  goes  first.  The 
latter  is  to  acknowledge  the  salutes  which  are  given  at  the  gang- 
way of  naval  vessels. 

Naval  vessels  fire  personal  salutes  to  officers  entitled  to  them 
when  the  boat  containing  the  officer  to  be  saluted  has  cleared 
the  ship.  It  is  an  acknowledgment  for  his  boat  to  u  lie  on  her 
oars"  from  the  first  until  the  last  gun  of  the  salute,  and  for  the 
officer  saluted  to  uncover,  then  at  the  conclusion  to  "give  way." 

The  exchange  of  official  visits  between  the  commanding  officers 
of  a  post  and  vessel,  opens  the  door  to  both  official  and  social 
courtesies  among  the  other  officers. 

HO.  To  a  boat  with  the  flag  of  an  admiral,  vice-admiral,  or 
rear-admiral,  or  the  broad  pennant  of  a  commodore,  boats  with 
narrow  pennants  "lie  on  their  oars"  or  "let  fly  their  sheets," 
and  boats  without  pennants  "toss  their  oars."  In  both  cases 
officers  in  them  salute. 

In  the  case  of  two  boats  meeting  or  passing  each  other,  each 
with  the  same  insignia  of  a  commanding  officer,  the  junior  is  the 
first  to  salute. 

Officers  of  inferior  grade  to  a  commanding  officer  passing  him 
in  a  boat,  "lie  on  their  oars"  or  "let  fly  their  sheets,"  and 
salute.  All  other  officers  passing  eacli  other  in  boats  are  to  ex- 
change salutes,  the  junior  saluting  first. 

Cockswains  steering  boats  are,  whenever  commissioned  officers 
are  saluted,  to  stand  up  and  raise  their  caps,  and  whenever 
warrant  officers  are  saluted  they  raise  their  caps  only. 

The  officer  or  cockswain  of  a  loaded  boat,  or  of  boats  engaged 
in  towing,  salute  a  boat  with  the  flag  of  an  admiral,  vice-admiralr 
or  rear-admiral,  or  the  broad  pennant  of  a  commodore,  by 
standing  and  raising  their  caps. 


OFFICIAL   COUKTESIES.  465 

When  boats  are  rowing  in  the  same  direction,  an  inferior  is 
not  to  pass  a  superior  in  grade  unless  he  U  on  urgent  duty,  or 
authorized  by  the  superior. 

When  boats  are  pursuing  opposite  directions,  the  rule  of  the 
road  to  prevent  fouling  is,  that  both  shall  uput  their  helms  to 
port " — i.  c,  to  pass  to  the  right,  circumstances  permitting. 

When  boats  are  approaching  the  same  landing  or  vessel,  an 
inferior  is  always  to  give  way  to  a  superior  in  rank. 

Boats  about  leaving  a  ship's  side  or  landing  are  to  give  way  in 
ample  time  to  others  approaching. 

It  is  not  proper  to  land  over  another  boat  without  permission, 
and  only  when  it  cannot  be  avoided  is  permission  to  be  asked. 

Boats  display  their  ensigns  when  they  shove  off,  and  keep 
them  flying  until  their  return. 

71 1.  To  distinguish  officers  in  boats,  commanding  officers  of 
fleets,  squadrons,  or  divisions  carry  the  distinguishing  marks  of 
their  rank  on  the  bow  of  their  barges.  Flags  and  pennants  dis- 
tinguishing rank  are  also  worn  at  the  bows  of  boats. 

Au  admiral's  flag  is  a  blue  flag  bearing  four  white  stars;  that 
of  a  vice-admiral  bears  three  stars;  a  rear-admiral,  two  stars;  a 
commodore's  pennant,  one  star,  and  is  a  swallow-tailed  flag. 

The  narrow  pennant  is  worn  by  commanding  officers  of  lesser 
rank.  In  addition,  captains  in  the  Navy  wear  a  gilt  ball  on  the 
end  of  their  boat  staff's,  and  commanders  a  gilt  star. 

To  the  ships,  boats,  and  officers  of  the  Uuited  States  Navy,  as 
well  as  foreign  officers,  the  foregoing  is  due;  and  courtesy  be- 
tween the  land  and  naval  services  is  indispensable  to  good  order 
and  discipline,  as  well  as  necessary  to  the  national  dignity  and 
honor.  Military  officers  of  assimilative  rank  are  entitled  to  and 
should  carry  the  above  boat  insignia. 

Navy  regulations  require  officers  and  men  never  to  omit,  on 
any  occasion,  to  extend  the  same  compliracuts  to  officers  of  the 
Army  as  are  paid  by  them  to  officers  of  the  Navy. 

712.  When  a  civil  functionary  entitled  to  a  salute  arrives  at 
a  military  post,  the  commanding  officer  meets  or  calls  upon  him 
as  soon  as  practicable.  The  commanding  officer  will  tender  him 
a  review,  provided  the  garrison  of  the  place  is  not  less  than  four 
batteries  of  artillery,  or  their  equivalent  of  other  troops. 

When  an  officer  entitled  to  a  salute  visits  a  post  within  his 
own  command,  the  troops  are  paraded  and  he  receives  the  honor 
of  a  review,  unless  he  directs  otherwise. 

When  a  salute  is  to  be  given  an  officer  junior  to  another  pres- 
ent at  a  post,  the  senior  will  be  notified  to  that  effect  by  the  com- 
manding officer. 

Military  or  naval  officers,  of  whatever  rank,  arriving  at  a  mil- 
30 


±66  FUNERALS. 

itary  post  or  station,  are  expected  to  call  upon  the  commanding 
officer. 

Under  no  circumstances  is  the  flag  of  a  military  post  dipped 
by  way  of  salute  or  compliment. 

Funerals. 

713*  When  the  funeral  of  an  officer  entitled,  when  living, 
to  a  salute,  takes  place  at  or  near  a  military  post,  minute-guns 
are  fired  while  the  remains  are  being  borne  to  the  place  of  inter- 
ment; but  the  number  of  such  guns  is  not  to  exceed  that  which 
the  officer  was  entitled  to  as  a  salute  when  living.  After  the 
remains  are  deposited  in  the  grave,  a  salute  corresponding  to 
the  rank  of  the  deceased  officer  will  be  fired — three  salvos  of 
artillery,  or  three  volleys  of  musketry. 

In  the  event  of  a  flag-officer  of  the  Navy,  whether  of  the 
United  States  or  of  a  foreign  country,  dying  afloat,  and  the  re- 
mains are  brought  ashore,  minute-guns  are  fired  from  the  ship 
while  the  body  is  being  conveyed  to  the  shore.  If  it  be  in  the 
vicinity  of  a  military  post,  the  flag  of  the  latter  is  displayed  at 
half-staff,  and  minute-guns  are  fired  from  the  post  while  the  pro- 
cession is  moving  from  the  landing-place.  These  minute-gnns 
are  not  to  exceed  in  number  that  which  the  officer  was  entitled 
to,  as  a  salute,  when  living. 

During  the  funeral  of  a  civil  functionary  entitled,  when  living, 
to  a  salute,  the  flag  is  displayed  at  half-staff,  and  minute-guns 
fired  as  before ;  but  neither  salute  nor  salvos  are  fired  after  the 
remains  are  deposited  in  the  grave. 

On  the  death  of  an  officer  at  a  military  post,  the  flag  is  dis- 
played at  half-staff,  and  kept  so,  between  the  hours  of  reveille 
and  retreat,  until  the  last  salvo  or  volley  is  fired  over  the  grave, 
or,  if  the  remains  are  not  interred  at  the  post,  until  they  are 
removed  therefrom. 

During  the  funeral  of  an  enlisted  man,  the  flag  is  displayed 
at  half-staff,  and  is  hoisted  to  the  top  after  the  final  volley  or 
gun  is  fired. 

All  military  posts  in  sight,  or  within  six  miles  of  each  other, 
display  their  flags  at  half-staff  upon  the  occasion  of  either  one 
doing  so.     The  same  rule  is  observed  toward  a  vessel-of-war. 

On  all  occasions  where  the  flag  is  displayed  at  half-staff,  it  is 
lowered  to  that  position  from  the  top  of  the  staff.  It  is  after- 
wards hoisted  to  the  top  before  being  finally  lowered. 

714.  Should  it  occur  that  salutes  which  are  due  to  any  for- 
eign official  or  dignitary  have  not  been  provided  for  in  the  fore- 
going paragraphs,  he  may  receive  the  salutes  and  honors  which 
are  awarded  him  in  his  own  country.  If  time  permits,  however, 
special  instructions  from  the  War  Department  should  be  sought. 


APPENDIX. 


AH  weights  and  dimensions  in  the  foregoing  pages  are  given. 
In  English  denominations. 

The  only  legalized  unit  of  weight  or  measure  in  the  United 
States  is  a  troy  pound,  brought  from  England,  by  Captain  Kater* 
in  1827.  This  pound  is  a  standard  at  30  inches  of  the  barometer 
and  62°  of  the  Fahrenheit  thermometer. 

The  standard  avoirdupois  pound  is  the  weight  of  27.7015  cubic 
inches  of  distilled  water  at  30  inches  of  the  barometer  and  62°  F. 
The  following  table  shows  the  relation  between  the  troy  pound 
and  the  avoirdupois  pound  : 

7000  grains  troy    =      1  pound  avoirdupois. 
5760  grains  troy    =      1  pound  troy. 
175  pounds  troy  =  144  pounds  avoirdupois. 
175  ounces  troy  =  192  ounces  avoirdupois. 
437.5  grains  troy  =      1  ounce  avoirdupois. 

In  the  United  States  artillery,  the  troy  grain  (7000  to  the 
pound)  is  taken  as  the  standard. 

2240  pounds  avoirdupois  make  a  ton  (long). 

2000  pounds  avoirdupois  make  a  ton  (short). 

The  former  is  used  by  the  English  for  all  purposes. 

Both  of  these  tons  are  in  common  use  in  the  United  States. 
Where  precision  is  required,  as  in  making  contracts,  Ac,  it  is 
customary  to  state,  in  pounds,  which  ton  is  meant. 

A  box  16  X  16.8  X  8  inches,  contains  1  bushel. 
12  x  11.2  X  8  inches,  contains  J  bushel. 
8  X  8.4  X  8  inches,  contains  1  peck. 
6  X  6  X  6.4  inches,  contains  1  gallon,  1  liquid  meas- 
4  X  4  X  3.6  inches,  contains  1  quart,  /         ure. 

Mbtbic  System. 

By  an  act  of  Congress  approved  July  28,  1866,  the  metric 
system  of  weights  and  measures  is  made  optional  in  the  United 
States,  and  the  act  provides  that  the  tables  in  a  schedule  an- 
nexed shall  be  recognized  "as  establishing,  in  terms  of  the 
weights  and  measures  now  in  use  in  the  United  States,  the 
equivalents  of  the  weights  and  measures  expressed  therein  in 
terms  of  the  metric  system ;  and  said  tables  may  be  lawfully 
used  for  computing,  determining,  and  expressing,  in  customary 
weights  and  measures,  the  weights  and  measures  of  the  metric 
system." 

(467) 


468 


APPENDIX. 


Schedule  annexed  to  act  of  July  28,  1866. 

MEASURES  OF  LENGTH. 


Metric  denom- 
inations. 

Values  in  metres. 

f 
Equivalents  in  denominations  in 
use. 

Myriametre. ...... 

10000. 

1000. 
100. 
10. 
1. 
0.1 
0.01 
0.001 

6.2137  miles. 

0 . 62137  mile,  or  3280  feet  and  10  in. 

328  feet  and  1  inch. 

893.7  inches. 

39.37  inches. 

8.937  inches." 

0.3937  inch. 

0.0394  inch. 

Decametre 

Decimetre 

25.39954113  millimetres ==  1  inch. 

0.30479449356  metres =  1  foot. 

0.91438348  metres =  lyard. 

1.6093149  kilometres =  1  mile. 

MEASURES  OP  SURFACE. 


Metric  denominations. 

Values  in 
sq.  metres. 

Equivalents  in  denominations  in  use. 

10000 

100 

1 

2.471  acres. 

119.6  square  yards. 

1550  square  inches. 

1  square  centimetre. 
1  square  decimetre.. 

1  square  metre 

1  square  metre 

1  square  metre 

1  square  inch 

1  square  foot 

1  square  yard 

1  square  mile 


0.15500591  square  inches. 
0.107642993  square  feet. 
10.7642993  square  feet. 
1.19604326  square  yards. 
0.0002471  acre. 
645.13669  square  millimetres. 
0.092899683  square  metre. 
0.83609715  square  metre. 
2.58989447  square  kilometres. 


MEASURES  OF  CAPACITY. 


7 

Equivalents  I 
ix 

n  rjpnnrnmations 

Metric  denominations  ana  values. 

i  use. 

Names. 

No.  of 
litres. 

Oubio  measure. 

Dry  measure. 

Liquid  or  wine 
measure. 

Kilolitre  or 

1000. 
100. 
10. 
1. 
0.1 
0.01 
0.001 

1  cubic  metre.... 

10  c.  deoimetres. 
1  c.  decimetre.  ... 
0.1  c.  decimetre. 
10  c.  centimetres 
lc.  centimetre.. 

1.308  c.  yds 

2  bus.  3.35  pks. 

6.1022  c.  inch.. 
0.6102  c.  inch.. 
0.061  c.  inch.... 

> 

264.17  gallons. 
26.417  gaUons. 
2.6417  gallons. 
1.0567  quarts. 
0.845  gill. 
0.338  fluid  oz. 
0.27  fluid  dr'm. 

Hectolitre ... 
Decalitre . ... 

Centilitre.... 
Millilitre 

METRICAL   EQUIVALENTS. 


469 


1  cubic  centimetre  (c.  c) =         0.0610270515194  c  bic  inches. 

1  cubic  decimetre =  61.0270515194  cubic  inches. 

1  cubic  metre =  61027.0515194  cubic  inches. 

1  cubic  metre ==  35.31658074  cubic  feet. 

1  cubic  metre........ =        1.3080215  cubic  yards. 

1  cubic  inch =  16.8861759  cubic  centimetres  (e.  e.) 

1  cubic  foot...........-*.— _•«•  =»        0.0283153119  cubic  metre. 

1  cubic  yard.. ....... .....«.._•«.  =  0.7645135  cubic  metre. 

WEIGHTS. 


Metric  denominations  and  values. 

Equivalents  in 

denominations 

in  use. 

Names. 

Number  of 
grammes. 

Weight  of  what  quan- 
tity of  water  at  max- 
imum density. 

Avoirdupois 
weight. 

Millier,  or  tonneau. 

1000000. 
100000. 
10000. 
1000. 
100. 
10. 
1. 
0.1 
0.01 
0.001 

10  litres 

2204.6  pounds. 
220.46  pounds. 
22.046  pounds. 
2.2046  pounds. 
3.5274  ounces. 
0.3527  ounce. 
15.432  grains. 
1.5432  grains. 
0.1543  grain. 
0.0154  grain. 

Kilogramme,  or  kilo 

1  litre 

1  decilitre 

Decigramme .... 

Centigramme.  ..*••*.. 
Milligramme.. ......... 

Additional  Metrical  Equivalents. 

1  surveyor's  chain  in  metres =    20.11662  ...  log.=  1.3035550 

1  metre  in  surveyor's  chain =     0.04971*...  log.=  8.6964450 

1  square  foot  in  square  metres..  =     0.09290*...  log.=  8.9680221 

1  acre  in  hectares =     0.40467*...  log.=  9.6071100 

1  square  mile  in  hectares =  258.994      ...  log.=  2.4132900 

1  square  metre  in  square  feet...  =    10.76410  ...  log.=  1.0319779 

1  hectare  in  acres ==     2.47109  ...  log.=  0.3928900 

1  hectare  in  square  miles =     0.00386*...  log.=  7.5867100 

1  cubic  foot  in  steres =     0.02831*...  log.=  8.4520332 

1  cord  in  steres =     3.62445  ...  log.=  0.5592432 

1  stere  in  cubic  feet =    35.31561  ....log.=  1.5479668 

1  stere  in  cords =     0.27590*....  log.=  9.4407568 

1  grain  in  grammes =     0.064798*..  log.=  8.8115680 

To  avoid  negative  characteristics,  10.  has  been  added  to  the 
logarithms  of  the  numbers  marked  *  in  the  above  table. 


470  APPENDIX. 

Miscellaneous. 

Length. — Gunter's  chain  =  66  feet  =  4  poles  =  100  links  of 

7.92  inches. 
1  fathom  =  6  feet ;  1  cable-length  =  120  fathoms. 
1  hand  =  4  inches;  1  palm  =  3  inches;  1  span  =  £ 

inches. 
Solid. — 1  cubic  foot  =  1728  cubic  inches. 

1  cubic  yard  =  27  cubic  feet  =  46656  cubic  inches. 
1  reduced  foot  (board-measure)  =  1  square  foot  X  1 

inch  thick  =  144  cubic  inches. 
1  perch  of  masonry  =  1  perch  (16 J  feet)  long  x  1  foot 

high  X  1}  foot  thick  =  24.75  cubic  feet ;  25  cubic 

feet  has  generally  been  adopted  for  convenience. 
1  cord  fire-wood  =  8  feet  long  X  4  feet  high  X  4  feet 

deep  =  128  cubic  feet. 
1  chaldron  coal  =  36  bushels  =  57.25  cubic  feet. 
Paper, — 24  sheets  =  1  quire. 

20  quires  =  1  ream  =  480  sheets. 

The  units  of  capacity  measure  are  the  gallon  for  liquid  and 
the  bushel  for  dry  measure.  The  gallon  is  a  vessel  containing 
58372.2  grains  (8.3389  pounds  avoirdupois)  of  the  standard 
pound  of  distilled  water,  at  the  temperature  of  maximum  den- 
sity, (39°.83  Fahrenheit,)  the  vessel  being  weighed  in  air  at 
62°  F.,  the  barometer  standing  at  30  inches. 

The  bushel  is  a  measure  containing  543391.89  standard  grains 
(77.6274  pounds  avoirdupois)  of  distilled  water,  weighed  as  above. 

The  gallon  is  the  wine-gallon,  of  231  cubic  inches,  nearly ;  and 
the  bushel,  the  Winchester  bushel,  nearly. 


WEIGHTS    AND    VOLUMES    OF    SUBSTANCES. 


471 


Weights  and  Volumes  of  various  Substances. 

metals. 


SUB8TAXCE8. 


Brass  J  Zinc 33  £ 

Brass,  grin-metal 

Copper,  cast 

plates 

Iron,  cast 

gun-metal 

wrought  bars.. 
Lead,  cast 

rolled 

Mercury,  60° 

Steel,  plates 

soft 

Tin 

Zinc,  cast , 

rolled 


CUBIC 

CUBIC 

FOOT. 

INCH. 

Founds. 

Pounds. 

488.75 

.2829 

643.75 

.3147 

547.25 

.3179 

643.625 

.3146 

450.437 

.2607 

466.6 

.27 

480.75 

.2816 

700.5 

.4106 

711.75 

.4119 

848.7487 

.491174 

487.75 

.2823 

480. 5G2 

.2833 

455.687 

.2637 

428.812 

.2482 

449.437 

.2601 

WOODS. 


SUBSTANCES. 


Ash. 

Cedar 

Chestnut 

Hickory,  pig-nut 

shell-bark.... 
Lignum  -  yitae 

Mahogany,  Honduras 

Oak,  Canadian 

English 

live,   seasoned.. 

white,  dry 

upland... 

Pine,  yellow 

Spruce 

walnut,  black,  dry.... 
Willow,  dry 


CUBIC 

CUBIC 

FOOT. 

FEET  IX  A 
TON. 

Pounds. 

52.812 

42.414 

85.062 

63.886 

38.125 

68.754 

49.5 

45.252 

43.125 

51.942 

83.812 

26.886 

5   35. 
i    66.437 

64. 

33.714 

54.6 

41.101 

58.25 

38.455 

66.75 

33.558 

53.75 

41.674 

42.937 

52.169 

33.812 

66.248 

31.25 

71.68 

31.25 

71.68 

30.375 

73.744 

472 


APPENDIX. 


MISCELLANEOUS. 


SUBSTANCES. 


Air 

Brick,  fire 

mean 

Coal,  anthracite 

bituminous,  mean 

cannel 

Cumberland 

Coke 

Cotton,  bale,  mean..: 

pressed 

Earth,  clay 

common  soil, 

gravel... 

dry  sand 

loose 

Granite,  Quincy 

Susquehanna.., 

Limestone 

Marble,  mean 

Mortar,  dry,  mean 

Water,  fresh 

salt 

Steam 


CUBIC 
FOOT. 


Pounds. 

.076291 
137.562 
102. 

89.75 
102.5 

80. 

94.875 

84.687 

62.5 

14.5 

20. 

25 
120.' 625 
137.126 
109.312 
120. 

93.75 
165.75 
1G9. 
179.25 
167.875 

97.98 

62.5 

64.125 
.036747 


CUBIC 

FEET  IN  A 

TON. 


16.284 

21.961 

24.958 

21.854 

28. 

23.609 

26.451 

35.84 

164.48 

114. 
89.6 
18.569 
16.335 
20.49 
18.667 
23.893 
13.514 
13.254 
12.462 
13.343 
22.862 
35.84 
34.931 


Alloys. 

Bronze  Gun-metal. — 90  copper  and  10  tin. 

Bell-metal. — 78  copper  and  22  tin. 

Fine  brass. — 2  copper  and  1  zinc. 

Brass  for  parts  of  gun-carriages. — 80  copper,  17  zinc,  and  3 
tin. 

Sheet  brass. — 3  copper  and  1  zinc. 

Silver  solder. — 4  silver  and  1  copper ;  or  2  silver  and  1  brass 
wire. 

Hard  solder. — 1  zinc  and  2  brass. 

Plumber'' s  solder. — 1  tin  and  1  lead. 

Tinner's  solder. — 1  tin  and  2  lead. 

Pewterer's  solder. — 2  tin  and  1  lead. 

Fusible  alloy.— -2  tin,  3  lead,  5  bismuth ;  melts  at  197°. 

Type-metal. — 11  lead,  2  antimony,  and  J  tin. 

German  silver. — 40J  copper,  31 J  nickel,  25J  zinc,  2J  iron. 


WEIGHT    SUSTAINED   BY    SHEAIl   SPAR. 


473 


.-' 


German  silver  for  casting. — 60  copper,  20  zinc,  20  nickel,  3 
lead. 

Pewter, — 4  tin  and  1  lead. 

An  alloy  that  expands  in  cooling. — 9  lead,  2  antimony,  and  1 
bismuth ;  useful  for  filling  small  cavities  in  cast-iron. 

Babbit's  metal,  for  journal-boxes. — 9  tin  and  1  copper. 

To  ascertain  the  Weight  that  a  Shear  Spar  will  Sustain  With' 

out  Breaking. 

The  case  is  that  of  a  cylindrical  beam  inclined  upward  and 
supported  at  each  end,  the  weight  applied  at  a  distance  m  from 
one  end. 

For  a  square  beam  in  this  position  the  for- 
mula will  be : 

Sid*        P 

W= X  -;  »n  which 

m  (I — m)     c* 
W=  the  weight 
S=  the  value  of  the  (Oak       8=50 
timber  for  general  use,  or        i  Y.  pine  S=50 

I W.  pine  S=45 
I  =s  the  length  between  supports  in 
feet.     (A  B.) 

d  =  the  diameter  or  side  of  the  beam 
in  inches.    (AE.) 

m  =  the  distance  in  feet  from  either 
point  of  support  to  the  point  where  the  weight 
is  suspended. 

c  =  the  inclination  of  the  shears  or 
the  horizontal  distance  between  the  heel  and 
upper  point  of  support  in  feet.    (BC.) 

For  a  cylindrical  beam  the  result  must  be  ■ 
multiplied  by  .78124. 


B  C 

Example.— Having  S  =  50,  I  =  27',  d  =  10",  m  =  2',  c  =10, 

SZ3d» 

then  W  = X  .78124  = 

m  (2— m)  c2 

50  X  19683  X  1000  X  .78124 

2  X  25  X  100 

19683  X  7.8124  =  154771.  lbs. 

This  is  only  calculated  for  a  steady  strain ;  the  result  should 


474  APPENDIX. 

be  diminished  at  least  one-half  to  allow  for  the  surge  of  the  fall 
around  the  capstan,  both  when  hoisting  and  lowering. 

To  ascertain  the  Strain  on  the  Guys  and  Spars, 

From  actual  measurement  of  the  ground,  &c,  construct  a  dia- 
gram as  follows : 

AB.  The  shears  at  their  ultimate  inclination. 

AC.  The  guy 8. 

AD.  A  vertical  line  representing  the  weight  suspended. 


With  any  scale  of  equal  parts  lay  off  on  the  line  A  D  the 
distance  equal  to  the  number  of  units  of  weight ;  say,  represent 
25  tons  by  25  inches;  through  the  point  E  thus  found  draw  EF 
parallel  to  A  0.  Then,  the  distance  E  F  measured  by  the  same 
scale  will  represent  the  strain  on  the  guys,  and  A  F  the  thrust 
on  the  spars. 

Precaution. 

In  selecting  spars  for  shears,  it  must  be  borne  in  mind  that  the 
strain  on  the  shears  is  equal  to  the  weight  lifted  plus  the  force  re- 
quired at  the  end  of  the  fall  to  suspend  the  weight. 

Mensuration. 

Area  of  a  triangle =    base  X  \  altitude. 

Area  of  a  parallelogram =    base  X  altitude. 


MENSURATION.  475- 

Area  of  a  trapezoid ={^8^  X  * thc  8l,ra  of  Pa,al,e> 

Area  of  a  trapezium -|dl^  lnto  ^l  V^"*1?*'  an(* 

*^  \     find  area  of  the  triangles. 

Circumference  of  a  circle...  =  diameter  X  3.1416. 

Diameter  of  a  circle =  circumference  X  .3188. 

Area  of  circle =  (diameter)  *  X  .7854. 

Area  of  sector  of  circle ■=  length  of  arc  X  i  the  radius. 

Area  of  segment  of  circle,  -  {  ^eJiZTtrt^^  ^ 

f  diameter  of  the  two  circles  X 

Area  of  circular  ring =«{     difference    of   diameter,   and 

I     that  product  by  .7854. 

Side  of  square  that  shall       f  diameter  X  .8862,  or  circumfer- 
equal  area  of  circle =\     ence  X  .282. 

Diameter   of    circle    that       ( 
shall  contain  area  of  a       «  side  of  square  X  1.1284. 
given  square =1 

Area  oi  an  ellipse ={Pr$}M. 0|  *"  tW°  d,*metere  X 

Area  of  parabola =    base  X  $  altitude. 

{sum  of  its  sides  x  perpendicular 
from  its  centre  to  one  of  its- 
sides,  -s-  2. 

Surface  of  cylinder -{"S£JKn£,,+  ^  * 

Contents  of  cylinder =    area  of  ends  X  length. 

Surface  of  sphere =    diameter  X  circumference. 

Contents  of  sphere ~  =    (diameter)  8  X  .5236. 

Surfaceofpyramldorcone.  - { ^^^hS^  b<lSe  *  i<>f  *•' 

^ne^jL^^.Z  ={ a«a  of  base  X  *  altitude. 
a.,**u~„  A*  ««.„,*,«m  ^4  ^„^        (  sum   of  circumference  at  both 

8  ™S  -1      cnds  *  *s,ant  *W*  +  «* 

or  pyramid —  I     of  both  ends. 

(multiply  areas  of  two  ends  to- 
gether and  extract  square  root. 
Add  to  this  root  the  two  areas- 
and  X  $  altitude. 


476  APPENDIX. 

Contents  of  a  wedge =    area  of  base  X  £  altitude. 

Contents  of  a  rinff  (thickness  +  inner  diameter  X 

contents  01  a  ring —  ^     gquare  of  thickness  x  2.4674. 

To  ascertain  the  distance  to  an  inaccessible  object ;  as,  for  in- 
stance, the  breadth  of  a  river :  (Fig,  4,  Plate  75.) 

1st.  The  line  A  B  (the  distance  to  be  determined)  is  extended 
^pon  the  bank  to  D,  from  which  point,  after  having  marked  it, 
lay  off  equal  distances,  CD  and  Gd:  produce  B  G  to  6,  making 
Gb  =  G B;  then  extend  the  line  do  until  it  intersects  the  pro- 
longation of  the  line  CA  at  a.  The  distance  a  6  is  equal  to 
A  2?,  or  the  width  of  the  river. 

2d.  Lay  off  any  convenient  distance,  B  C7,  perpendicular  to 
AB ;  erect  a  perpendicular,  DC,  to  AG ;  note  the  point  D 
where  it  intersects  A  B  produced ;  measure  B  D  ;  then — 

BG* 
ABssirD' 

Capabilities  of  the  Horse. 

The  average  weight  of  a  horse  is  about  1000  pounds ;  for  artil- 
lery purposes  he  should  average  1100  pounds.  In  ranks  he  occu- 
pies a  front  of  40  inches,  a  depth  of  10  feet ;  in  a  stall,  from  3.5 
to  4.5  feet  frout. 

The  load  for  a  light-artillery  horse  is  700  pounds,  including 
■carriage ;  for  heavy  field  artillery,  1000  pounds,  including  car- 
riage. This  is  less  than  that  allowed  for  the  ordinary  horse  in 
-civil  service,  in  consequence  of  bad  roads,  scant  forage,  and 
frequently  forced  marches. 

Including  the  weight  of  carriage,  four  horses  can  draw,  on 
roads  such  as  are  considered  in  America  good,  3000  pounds ;  six 
horses,  4000  pounds ;  eight  horses,  5000  pounds ;  and  ten  horses, 
6000  pounds.  This  allowance  diminishes  rapidly  as  the  roads 
become  bad. 

A  horse  will  pack  from  250  to  300  pounds,  20  miles  per  day- 
eight  hours.  The  mule  is  superior  to  the  horse  as  a  pack  ani- 
mal. An  ordinary  march  is  about  15  miles  per  day  of  eight 
J i ours,  depending  upon  the  state  of  the  roads,  condition  of  the 
.horses,  and  various  other  circumstances.  The  rate  of  march, 
with  horses  starting  fresh  and*  resting  for  a  few  minutes  each 
half-hour,  would  be  2.5  miles  for  the  first  hour,  4  miles  for  the 
next  two  hours,  and  8.5  miles  for  the  remaining  five  hours. 

A  horse  carrying  a  rider  marches,  at  a  walk,  at  the  rate  of 
3.75  miles  per  hour;  at  a  trot,  at  the  rate  of  7.50  miles  per  hoar; 
4it  a  gallop  (slow),  at  the  rate  of  11  miles  per  hour. 


CAST-IRON   BALLS. 


477 


A  horse  requires,  per  day,  4  gallons  of  water  and  12  pounds- 
of  short  and  14  pounds  of  long  forage. 

Iron. 

Strength.  The  mean  strength  of  American  wrought-iron  is 
55,900  pounds  to  the  square  inch;  of  English,  53,900  pounds. 
The  working  strain  is  from  one-sixth  to  one-fourth  the  mean 
strength. 

The  ultimate  extension  of  wrought-iron  is  *foth  part  of  its 
length. 

Test  quality.  If  the  fracture  gives  long,  silky  fibres  of  leaden- 
gray  hue,  fibres  cohering  and  twisting  together  before  breaking, 
the  iron  may  be  considered  tough  and  soft.  A  medium  even 
grain,  mixed  with  fibres,  is  a  good  sign.  A  short,  blackish  fibre 
indicates  badly-refined  iron.  A  very  fine  grain  denotes  a  hard, 
steely  iron,  apt  to  be  cold-short,  hard  to  work  with  the  file. 

Coarse  grain,  with  brilliant  crystalline  fracture,  yellow  or 
brown  spots,  denotes  a  brittle  iron,  cold-short,  working  easily 
when  heated  and  easily  welded. 

Cracks  on  the  side  of  a  bar  denote  hot-short  iron. 

Good  iron  is  readily  heated,  soft  under  the  hammer,  and  throws 
out  but  few  sparks. 

Steel. 

The  tensile  strength  of  good  steel  is  120,000  pounds  per  square 
inch.  The  properties  are :  After  tempering,  not  easily  broken  ; 
welds  readily ;  does  not  crack  or  split ;  bears  a  very  high  heat ; 
can  be  hardened  after  repeated  workings ;  is  magnetic,  and,  as 
distinguished  from  iron,  when  once  magnetized  does  not  lose  its 
polarity  at  ordinary  temperatures. 


CAST-IRON  BALLS. 


Diameter. 

Weight. 

DlAMETEB. 

Weiqht. 

Diameter. 

"Weight. 

Inches. 

Lbs. 

Inches. 

Lbs. 

Inches. 

Lbs. 

2 

m 

8 
3* 

4 
4K 

1.09 
2.13 
3.68 
5.84 
8.73 
12.42 

5 

m 

6 

7 

7fc 

17.04 
•     22.68 
29.45 
37.44 
46.76 
57.52 

8 

m 

9 

10 
11 
12 
15 

69.81 

83.73 

99.40 
136.35 
181.48 
235.65 
450.28       , 

478 


APPENDIX. 


BOUND  CAST-IRON. 
Weight  of  a  lineal  foot 


Diameter. 

Weight. 

Inches. 

Lbs. 

2 

9.82 

m 

15.34 

3 

22.09 

3H 

30.07 

4 

39.27 

4* 

49.70 

Diameter. 

Weight. 

Inches. 

Lbs. 

5 

61.36 

5* 

74.25 

6 

88.36 

6H 

103.70 

7 

120.26 

m 

138.06 

Diameter. 

Weight. 

Inches. 

Lbs. 

8 

157.08 

83* 

177.33 

9 

198.80 

10 

245.44 

11 

296.98 

12 

353.43 

15 

552.23 

The  foregoing  tables  furnish  means  of  determining  approxi- 
mately the  weight  of  elongated  projectiles,  thus :  Ascertain  from 
the  second  table  the  weight  of  the  cylindrical  portion  of  the  pro- 
jectile, and  add  to  it  half  the  weight  of  a  solid  shot  of  corre- 
sponding calibre  taken  from  the  first  table. 


INDEX. 


[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 


Abattis,  397,  644 ;  308,  645. 

to  clear  away,  406,  654. 

Aiming,  (see  Ranges;  Sights;  Traversing,)  59,  207;  80,  230, 
XII;  81,  230,  XXIV;  81,  230,  XXII;  90,  243; 
145,  340. 

at  moving  vessels,  350,  588;  355,  592. 

at  night,  356,  592. 

at  unseen  objects,  404,  659. 

effect  of  mirage,  58,  206. 

of  mortars,  63,  212;  63,  213;  64,  213;  148,  342, 

343 ;  149,  343 ;  163,  365 ;  167,  372 ;  170,  378 ; 
356,  593. 
Air-cylinders,  68,  218. 
Ammunition,  41,  180. 

for  defense  of  defiles,  418,  66V. 

for  field  service,  93,  255;  101,  258. 

for  field-works  and  sieges,  316,  568;  390,  637;  410, 

660;  411,  662;  413,  666;  416,  666;  418,  66  V. 

—  for  permanent  works,  316,  568. 

preparation  of,  81,  230,  XV,  XX,  XXI,  XXVII;  90, 

244;  108,  275;  110,  277;  121,  294. 

reports  of,  413,  666;  414,  666;  415,  666. 

Anchors  as  holdfasts,  264,  521. 

for  targets,  190,  409. 

mushroom,  436,  6YT. 

Angle  of  fall,  39,  161 ;  377,  619. 

Angle  of  fire,  (see  Sights;  Range-tables,)  40,  173. 

Annual  supplies  of  armaments,  315,  507. 

Armament  of  works,  316,  568;  343,  581. 

Armor,  artillery  against,  347,  586;  353,  590;  354,  591. 

Armored  vessels,  (see  Iron-dads,)  348,  587;  351,  589. 

vital  points,  351,  589. 

Artillery  against  armor,  347,  586. 

(479) 


480  INDEX. 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Artillery  command  in  defenses,  346,  583 :  410,  660 ;  411, 661 ; 

411,  663 ;  417,  666. 
garrison,  sea-coasfc,  and  siege  distinguished,  1,  41;  1,  5; 

1,  6;  2,  8. 

in  connection  with  torpedo  service,  425,  6 TO. 

in  constructing  lines,  373,613;  410,  660;  411    661. 

in  attacking  intrenched  positions,  403,  649:  404.  650; 

405,651-653. 
in  defense  of  besieged  places,  410,  660. 

in  defense  of  defiles,  417,  667;  418,  66?. 

—  in  defense  of  river-crossings,  419,  668 ;  420,  668. 

in  harbor  defenses,  343,  581 ;  345,  582. 

proportion  of,  in  sieges,  411,  662. 

to  accompany  assaulting  parties,  406,  654. 

material,  annual  supply  to  preserve,  315,  567. 

care  and  preservation  of,  293,  551;  294,  555;  312, 

566. 

projectiles,  310,  565. 

required  for  sieges,  412,  664 ;  413,  664. 

storage  of  gunpowder,  316,  569. 

store-houses,  312,  566. 

transportation,  321,  57 1 ;  325,  573. 

disembarkation,  335,  578. 

railroad,  322,  572. 

weight  of  field  battery,  330,  574. 

Assault.    (See  Attack.) 

defense  against,  410,  660. 

Atmosphere,  pressure  upon  projectiles,  57,  206 ;  58,  206. 
Attack  and  defense  of  positions,  403,  649 ;  405,  652. 

advantages  of  attack,  405,  651. 

of  defiles,  417,  667;  418,  667. 

of  river-crossings,  419,  668;  420,  668. 

of  submarine  mines,  455,  692. 

selection  of  point  of  attack,  409,  659. 


Axis,  35,  134. 

Backward,  defined,  201,  419. 
Balls,  iron,  weight  of,  477,  Appendix. 
Barbette  batteries,  field,  384,  633. 

guns,  handled  with  gins,  250,  497. 

Barrels,  gunpowder,  to  sample,  46,  182. 

Barrow,  hand,  260,  512. 

Base-line,  permanent,  for  target  practice,  189,  409. 


INDEX.  481 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 


Base  of  breech,  35,  138. 

Battalion,  artillery,  formation,  28,  116;  29,  117-123;  30, 
124,  125;  31,  125,  126;  32,  126. 

to  form,  32,  127;  33,  127-130. 

Batteries.    (See  Field  Intrenchmcnts.) 

barbette,  384,  633. 

classified,  396,  642. 

commanding  defiles.  417,  667;  418.  667. 

commanding  rivers,  419,  668;  420,  668. 

designation  in  sieges,  413,  665. 

dispersion,  344,  581. 

distances  from,  in  defense  of  towns,  376,  617. 

elevation  of,  347,  585. 

embrasure,  385,  634;  396,  641. 

intrenched  positions,  403,  649. 

location  of,  364.  600;  366,  603,  604;  373,  613; 

388.  635 ;  408,  656. 

materials  for,  357,  594;  412,  664;  413,  664. 

mortar,  397,  643. 

pan-coupde,  384,  633. 

penetration  of,  357,  595;   358,  595;   359,  595;  360, 

595;  362,  596;  363,  596,  597;  364,  598. 

positions  of,  in  attack  of  intrenched  places,  403,  649. 

selection  of,  371,  612. 

strength  and  composition,  355,  592 ;  411,  662. 

to  construct,  395,  641. 

traverses  for,  376,  618;  388,  635. 

troops,  number  for,  345,  585. 

Battery,  commands  in,  8,  31 ;  8,  35 ;  10,  42. 

field,  weight  of,  330,  574. 

posts  of  officers,  non-commissioned  officers.  &c.  7,  24- 

30;  24,  103. 

siege-gun,  composition  of,  92,  255. 

ammunition  for,  316,  568. 

siege  mortar,  Coehorn,  159,  359. 

subdivisions  of,  6,  19-23;  8,  32-34;  10,  48. 

substituted  for  "company"  in  foot-drill  commands,  34, 

130. 

to  change  posts,  27,  112. 

to  form  at  the  pieces,  26,  107,  108. 

to  form  the,  8,  37. 

to  leave  the  pieces,  27,  113;  2S,  114,  115. 

to  load  a,  on  cars,  324,  572. 

31 


482  INDEX. 

[Note. — The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 


Battery  to  march  to  the  pieces,  25,  106. 
to  rest,  27,  HO. 

to  resume  the  exercise,  27,  111. 

— wagons  for  the  siege,  100,  258. 

what,  6,  19. 

Beds  for  piling  projectiles,  311,  565. 
Bic Word's  fuse,  422,  669. 
Bight,  232,  477. 
Blockades,  407,  655. 
Block-house,  400,  648. 
Blocks,  270,  528 ;  238,  482. 

storage  of,  313,  566. 

Blowing-charges,  188,  404. 

Boats,  compliments,  464,  709,  710;  465,  Til. 

Body  of  piece,  35,  1 40. 

Bomb-proofs,  394,  639. 

Books.    (See  Records.) 

Bore,  35,  132;  36,  144;  38,  153. 

— ■ inspection  of,  300,  561. 

record  of  defects  of,  307,  563. 

Bottom  of  bore,  36,  143. 

Boulenge*  telemeter,  192,  409-411. 

Boyaux,  408,  651;  409,  658. 

Brass  implements,  preservation  of,  313,  566. 

Breaching  earth- works,  361,  595. 

walls,  409,  659. 

Breech,  34,  137. 

Breech  sight,  59,  2©7;  60,  208,  209. 
Bridges,  covered  by  tetes-de-pont,  419,  668. 

demolition  of,  421,  669;  422,  669;  423,  669. 

for  disembarkations,  335,  578;  341,  579. 

weight  of  troops  on,  341,  579. 

Browning  of  guns,  296,  557. 
Budge-barrels,  54,  205. 
Buffers.    (See  Recoil  Checks.) 

hydraulic,  68,  218;  294,  555. 

pneumatic,  69,  219;  135,  320;  294,  555. 

Buildings,  demolition  of,  421,  669. 

Bung-stoppers  for  submarine  mines,  444,  683. 

Buoys,  445,  685. 

Bursting  of  shells  in  bore,  298,  558. 

Bushing  of  vent,  36,  142. 

Butler  projectile,  49,  190. 


INDEX.  483 

[Not*.— The  plain  figures  refer  to  the  pages  of  thi*  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

€ abt,es,  electric,  443,  682 ;  445,  686 ;  446,  686 ;  447,  686. 

to  lead  into  forts,  449,  688,  689. 

for  bridges,  341,  579. 

Caissons,  for  siege-gun  batteries,  93,  355. 

for  siege  mortars,  158,  359. 

•Caked  gunpowder,  to  test,  47,  183. 

Calibre,  38,  153. 

Calipers,  300,  560. 

Camps,  intrenched,  364,  601 ;  375,  614,  616;  412,  663. 

Canal -boats  as  lighters,  336,  578. 

Canals,  demolition  of,  423,  669. 

Canister,  49,  192. 

double  charges,  131,  318. 

Cannon,  construction  of,  34,  131;  36,  144;  37,  146-150; 
38.  154. 

marks  on,  293,  553. 

powder,  42,  ISO;  43,  ISO. 

to  disable,  309,  564. 

Cannoneers,  in  lines  of  works,  375,  616. 

posts  of,  81,  230,  XXn,  XXIII,  XXV,  XXVI. 

reliefs,  in  service,  82,  230,  XXXI. 

•Canvas  muzzle-hoods,  295.  555. 

Capstan,  262,  517;  275,  535;  276,  535;  290,  549. 

storage  of,  313,  566. 

to  use  a  gin  as,  262,  518. 

Carcass,  40,  194. 

Carriages,  artillery,  in  general,  65,  215,  216;  66,  216;  67, 
217;  68,  217,  218;  69,  219-221;  70,  221- 
223 ;  71,  223. 

barbette,  described,  1,  7 ;  2,8n.;  67,217;  109,276; 

115,  286,  288 ;  119,  293 ;  126,  306 ;  127,  308. 

care  of,  295,  555,  557. 

« casemate,  described.  1,  7;  67,  217;  117,  290. 

platforms,  71,  224. 

centre-pintle,  67,  217;  120,  293. 

depressing,  69,  221. 

8-inch  new  rifled  gun,  135, 320 ;  136,  320 ;  137,  320. 

■ field-gun,  platforms  for,  74,  226. 

flank-casemate,  70,  223 ;  128,  309. 

front-pintle,  67,  217;  126,  306. 

Gatling  gun,  0.45-inch,  181,  398. 

— Hotchkiss  gun,  183,  400. 

* mortar,  1,  7;  2,  8n.;  70,222;  157,357;  158, 359. 


484  INDEX. 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Carriages,  mortar  platforms,  71,  224;  75,  227;  76,228;  77,. 

229 ;  78,  229. 
r  recoil  checks,  41,  179;  117,  290. 

siege-gun,  1,  7;  2,  8n. ;  84,  231. 

platforms,  71,  224;  72,  225;  73,  225;  84,. 

231. 

Cars,  to  load  with  horses,  322,  572. 

siege-guns,  guns,  or  wagons,  324,  572. 

Cartridge-bags,  47,  185;  154,  354;  298,  558. 

■ —  preservation  in  store,  312,  566. 

Cartridge-pouch,  55,  205  ;  79,  23©,  IV. 
Cartridges,  dummy,  83,  230,  XXXVII;  104,  262. 

to  be  filled  at  depots.  416,  666. 

to  fill  and  prepare,  154,  354;  310,  570. 

to  insert,  80,  230,  IX;  88,  240;  151,  346. 

— -  to  withdraw,  81,  230,  XVI;  91,  247;  117,  289? 

125,  304 ;  153,  350. 
Cascable,  35,  139. 
Casemate  guns,  handled  with  casemate  trucks,  257,  506. 

gins,  249,  496. 

Casemates,  iron,  field,  400,  648;  401,  648. 
Casemate  truck,  257,  506. 

to  use,  257,  506 ;  25S,  506. 

Case-shot,  48,  189,  190;  49,  190,  191. 

Cease  firing,  81,  230,  XVI;  90,  244;  91,  247;  117,  289;. 

125,  304. 
Chains,  iron,  weight  and  strength,  241,  484. 
Chamber,  36,  144. 
Charge,  36,  144;  131,  318. 
Charging  shells,  108,  275;  165,  368;  298,  558. 

blowing  charges,  18S.  404. 

Chase,  35,  141. 

Chassis,  67,  217. 

Cheeks  of  carriages.  66,  216. 

Chocks,  200,  416;  210,  444;  270,  532. 

storage  of,  313,  566. 

Circuit-closers  for  mines,  452,  691. 
Circumvallation,  line  of,  410,  661. 
Coehorn  mortar  battery,  159,  359. 
Collar,  for  chase,  270,  531. 
Combination  fuse,  51,  199. 

Command  of  artillery  in  defenses,  346,  583;  410,  660;  411, 
661 ;  411,  663. 


i 


INDEX.  485 

[Notb.— The  plain  figures  refer  to  the  pages  of  this  Tolame.    The  fall- 
faced  figures  refer  to  paragraphs.] 

Command  of  artillery  in  sieges,  346,  583 ;  410,  .660 ;  411, 661 ; 

411,  663 ;  417,  666. 
•Commands,  8,  31;  10,  42,  43;  81,  230,  XXV;  82,  230, 

XXVIII. 

"battery"  for  "company,"  34,  ISO. 

"detachments"  to  replace  "fours,"  34,  130. 

Compressor-bars,  135,  320. 

Concussion-fuse,  51,  199. 

Conversion  of  cannon,  34,  131;  35,  132;  132,  319. 

Cordage,  231,  416. 

preservation  of,  238,  481 . 

strength  of,  237,  481 ;  238,  481. 

Counter-hurtere,  68,  217. 
Countervallation,  line  of,  410,  661. 
Coupling  for  top-carriage  and  chassis,  135,  320. 
Courtesies,  official,  463,  708. 
Cradle,  261,  516;  275,  535. 

storage  of,  313,  566. 

Cross-lifting,  203,  427. 

Cubical  (pellet)  powder,  42,  ISO;  46,  181. 

Cutting  guns,  (mechanical  manoeuvres,)  204,  430. 

Cylinder-gauge,  300,  560. 

Cylinder-staff,  299,  560. 

Dampness  of  powder.    (See  Gunpowder  tests.) 
Defense  of  besieged  positions,  410,  660,  661. 

of  defiles,  417,  667;  418,  667. 

of  river-crossings,  388,  636 ;  419,  668 ;  420,  668 ; 

425,  670. 
Defenses  of  harbors,  343,  581 ;  388,  636. 

■  distances  from  towns,  (see  Submarine  Mines,)  876,  61V. 

number  of  troops  required,  345,  582. 

position  of  batteries,  343,  581. 

strength  of  batteries,  355,  592 ;  356,  593. 

submarine,  346,  584. 

Defensive  intrenchments.    (See  Field  Intrench  me  nts.) 

distances  from  towns,  376,  6 IT. 

Defilading  field-works,  377,  619;  378,  619. 
Defiles,  417,  667;  418,  667. 

rivers  considered  as,  419,  668. 

Demolition  of  bridges,  421,  669 ;  422,  669  ;  423,  669. 

buildings,  421,  669. 

canals,  423,  669. 


486  INDEX. 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  fall- 
faced  figures  refer  to  paragraphs.] 


Demolition,  explosives  for,  430,  675. 
Depots,  siege,  413,  666 ;  416,  666. 
Depression,  39,  163. 
Derricks,  described,  288,  548 ;  289,  548. 

garrison,  gin,  252,  501. 

in  landing  heavy  guns,  339,  578. 

to  lower  15-inch  gun,  291,  550. 

to  raise  15-inch  gun,  290,  649. 

Detachments  replace  u fours"  in  commands,  34,  130. 

to  change  posts,  27,  112. 

to  form  at  the  pieces,  26,  107 ;  26,  108. 

for  artillery  service,  5, 14-17 ;  6,  21 ;  6, 23  ^ 

8,37;  9.  38-41. 

for  fatigue,  9,  40. 

for  leaving  the  pieces,  26,  107;  26,  108. 

for  marching  drill,  9,  41. 

to  march  to  the  pieces,  26,  107,  168. 

to   prepare   for  mechanical  manoeuvres,  201r 

419,  426. 

what,  5,  12 ;  5,  13. 


Deviation,  41,  177;  56,  206;  57,  206;  58,  206;  59,  206; 
186,  402;  192,  409. 

Directrix,  41,  179. 

Disabling  cannon,  309,  564. 

Dispart,  37,  145. 

Distances,  for  Coehorn  mortar  target,  188,  406. 

for  sea-coast  gun  targets,  189,  409. 

for  sea-coast  mortar  targets,  189,  407 ;  189,  408. 

for  siege-gun  targets,  184,  402. 

for  siege-howitzer  targets,  187,  403. 

for  siege-mortar  targets,  187,  404 ;  188,  404. 

of  defensive  works  from  towns,  376,  617. 

to  ascertain,  184,  402;  191,  409. 

by  telemeter,  192,  411 ;    193,  411,  412. 

Ditches,  378,  620;  400,  648. 

Drift,  41,  178. 

Drill.   (See Manoeuvres,  Mechanical;  Manoeuvres,  Tactical.) 

Drop  of  projectile,  table,  404,  650. 

Dualine,  431,  675. 

Dyer's  pointing  apparatus,  63,  213;  64,213;  168,372;  170,. 

378 
Dynamite,  431,  675. 
in  demolitions,  421,  669;  431,  675. 


INDEX.  487 

[Notjb.— The  plain  figures  refer  to  the  pages  of  this  Yolume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Earth- works,  (see  Field  Tntrenchraents,)  357,  594,  595. 
penetration  of,  358,  595 ;  350,  595 ;  360,  595 ;  362, 

596;  363,  596,  59  1. 
revetments,  362,  596;  363,  596;   377,  618;    379, 

622,623;  380,624;  381,625,626;  382,627, 

628;  383,629. 
thickness,  362,  596. 

to  breach,  360,  595;  361,  595. 

Eccentric  rollers,  136,  320. 

Effect  of  projectiles,  striking,  352,  590;  353,  590. 

how  to  be  observed,  185,  402. 

Electrical  submarine  mines,  425,  611;  426,  611. 

testing-rooms,  449,  689;  456,  693. 

Electric  batteries,  450,  689. 

cables,  443.  682 ;  445,  686 ;  446,  686 ;  447,  686. 

to  lead  into  forts,  449,  688,  689. 

fuses,  440,  680. 

primers,  51,  201. 

in  demolitions,  421,  669. 

Elevating-arc,  60,  208;  60,  209;  138,  320. 
Elevating-bar,  56,  205 ;  66,  216. 
Elevating-screw,  67,  216;  294,  555. 
Elevation,  39,  162;  82,  230,  XXXIII,  XXXIV. 

of  batteries,  377,  585. 

Embarkation  of  artillery,  321,  511. 

horses,  328,  513;  329,  514;  333,  516. 

of  unsuccessful  expeditions,  340,  519. 

Embrasure  batteries,  385,  634. 
Energy  of  projectiles,  39,  161. 
Engineers,  functions  in  besieging  positions,  411,  661;  411, 

663. 
Entanglements,  397,  644. 

■         to  clear  away,  406,  654. 
Epaulments,  376,  618. 
Equipments,  53,  203. 

for  officers,  413,  664. 

preservation  of,  313,  566. 

Explosion,  41,  180. 

Explosives,  (see  Dualine ;  Dynamite ;  Gun-cotton  ;  Gunpowder; 
Lithofracteur;  Nitro-glycerine,)  41 ,  ISO;  430,615. 

Fascines  for  revetments,  380,  624. 
Feeding  horses  at  sea,  328,  513. 


488  INDEX 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  lull- 
faced  figures  refer  to  paragraphs.] 

Field-glass  for  each  siege  gun,  95,  257. 
Field-gun  platforms,  74,  226. 
Field  intrenchments,  357,  594. 
attack  and  defense,  403,  64&. 

bastioned  works,  369,  611 ;  370,  611 ;  371,  611. 

batteries,  barbette,  384,  632. 

embrasure,  385,  634;  396,  641. 

pan-eoup6e,  384,  633. 

besieging,  407,  656. 

block-houses,  400,  648. 

bomb-proofs,  394,  639. 

camps,  to  lay  out,  364,  601 ;  375,  616. 

classified,  396,  642. 

defiles,  417,  667;  418,  667. 

detached  works,  to  lay  out,  366,  603,  605 ;  367,  606- 

608;  368,  61 0. 

ditches,  378,  620. 

entanglements,  397,  644. 

fascine  revetments,  380,  624. 

garrisons  for,  367,  609 ;  368,  609 ;  370.  611;  374, 

614. 

gun  batteries,  location  of,  364„  600 ;  388,  635. 

guns  and  mortars  for,  371,  612. 

interior  arrangement,  384,  630. 

lines  of  battle,  to  lay  out,  364,  602;  372,  613. 

lines  of  works,  to  lay  out,  372,  613;  373,  613;  374, 

613,  614;  375,  614,  615. 

magaziues,  service,  392,  637. 

storage,  390,  637. 

mortars  in,  397,  643. 

parapets,  ditches  of,  378,  620. 

form  of,  376,  618  ;  377,  618,  619 ;  378,  619. 

penetration  of,  358,  595  ;  359,  595  ;  360,  595; 

362,  596;  363,  596,  597. 

slopes  of,  (tables,)  377,  619;  378,  619:  379, 

621. 

thickness  of,  362,  596;  378,  619. 

platforms  for  batteries,  387,   635;    388,  636;   397, 

643. 

profiling,  379,  621. 

revetments,  362,  596;    363,   596;   377,  618,  379, 

622,  623 ;  380,  624  ;  381,  625 ;  381,  626 ;  382, 
627,  628;  383,  629. 


INDEX.  489 

[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Field  intrenchments,  river-crossings,  attacking,  420,  668. 

defending,  419,  668. 

sea-coast,  388,  636. 

splinter-proofs,  393,  63 1. 

to  breach,  361,  595  ;  379,  621. 

tracing,  379,  6*1. 

traverses,  376,  618 ;  388,  635 ;  393,  638 ;  394,  638. 

Fire,  armor  against,  347,  586. 
— '• —  curved  or  vertical,  38.  156;  356,  593. 

direct  or  horizontal,  38,  155;  347,  585. 

earth-works,  to  bread),  361,  595. 

kinds,  during  attack,  406,  654. 

magazines,  to  destroy,  360,  595. 

night  repairs,  to  prevent.  361,  595. 

plunging,  39,  159. 

rapidity  of,  127,  308. 

ricochet,  38,  151;  347,  585;  350,  581. 

rolling,  38,  158. 

to,  80,  230,  XIH;  90,  243,  244;   91,  241;  115, 

286  ;  125,  301 ;  153,  348. 

• vessels,  moving,  350,  588 ;  355,  592. 

Fire-ball,  50,  195. 

Fire-works,  storage  of,  317,  569;  318,  569. 

Firing  at  night,  356,  592. 

mines,  450,  690;  451,  690;  452,  690;  453,  690. 

reports  of,  during  sieges,  416,  666. 

rules  for  target,  183,  401. 

salutes,  460,  698. 

Flag  at  half-staff,  466,  113. 

never  dipped  at  posts,  466,  112. 

Forces  acting  on  projectile,  57,  206. 
Formula,  cordage,  to  find  strength  of,  238,  481. 

guys,  to  find  strain,  474,  App. 

lighters,  to  find  capacity,  341,  519. 

parapet,  to  find  number  of  men  for,  345,  582 ;  367, 

609;  368,  609;  370,  611. 

powder,  to  find  charge  for  bridge  demolitions,  421,  669. 

projectile,  to  compute  energy,  39.  161. 

to  compute  number  in  piles,  312,  565. 

to  find  weight  of,  478,  App. 

ranges,  to  find  elevation,  61.  210. 

to  find  for  mortars,  154,  354. 

shears,  to  find  strength  of,  473,  App. 


490  INDEX. 

[Note. — The  plain  figures  refer  to  the  pages  of  this  Yolume.    The  fall- 
faced  figures  refer  to  paragraphs.] 

Forts,  bastioned,  369,  611;  370,  611 ;  371,  611. 

command  of  artillery  in,  34G,  583. 

complements  of  men  for,  345,  582;  367.  607;  368, 

6©7 ;  370,  611 ;  374,  614. 

distances  from  towns,  376.  611. 

submarine  defenses,  346,  584. 

Forward,  defined,  201,  419. 

Friction  against  bore,  influencing  projectile,  58,  206. 

Friction-bars,  69,  22©. 

Friction-primers,  51,  200. 

preservation  of,  313,  566. 

Front  sight,  59,  207 ;  60,  208  ;  60,  209. 

Fulminate  of  mercury,  433,  675. 

Funeral  honors,  466,  'VIS. 

Fuse-block,  55,  205. 

Fuse-gauge,  55,  205. 

Fuse-hole  in  elongated  shells,  49,  190. 

in" spherical  shells,  48,  188. 

Fuse-knife,  55,  205. 
Fuse-plug  extractor,  55,  205. 
Fuse-plugs,  110,  277. 
Fuse- reamers,  55,  205. 
Fuses,  50,  196. 

blasting,  422,  669. 

combination,  51,  199. 

concussion,  51,  199. 

electric,  440,  680. 

ignition,  to  secure  in  mortar,  165,  368. 

mortar  fuse-plugs,  51,  197 ;  165,  368. 

paper  time,  51,  197. 

percussion,  51,  198. 

position  in  mine  charges,  441,  681. 

preservation  of,  313,  566. 

sulphuric  acid,  439,  679. 

time,  50,  197. 

water-cap  fuse-plug,  50,  197. 

Fuse-setter,  54,  2©5. 
Fuse-wrench,  55,  205. 

Gabion  revetments,  381,  626 ;  386,  634 ;  393,  638. 

Gabions,  382,  626. 

Garrison  gin-derrick,  (narrow,)  252,  501. 

Garrison  trucks,  painting  and  storage,  314,  566. 


INDEX. 


491 


[Note.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Gatling  guns.    (See  Guns,  Gatling.) 

against  assaults,  410.  666. 

lor  block-houses,  400,  648. 

not  substitutes  for  artillery,  371,  612. 

Gauging  bores,  297,  558.  _A  m  ^^^ 

General  rules  for  service  of  piece,  79,  230 ;  86,  234-236 ;. 
87,  238,  239. 

for  target  practice,  183,  401. 

for  traversing  in  aiming,  81,  236,  XXIV;  145,  340. 

Gins  as  capstans,  262,  518. 

as  shears,  252,  500. 

described,  242.  485. 

dimensions,  weights,  &c,  25*2,  499. 

■  garrison  and  casemate,  248,  495  ;  240,  495. 

painting  and  storage,  313,  566 ;  314.  566. 

Piper's,  247,  494. 

ropes  for,  244,  489. 

—  to  lower,  244,  488. 

to  move,  244,  488. 

—  to  put  together,  243,  488. 

' to  raise,  243,  488. 

to  shift  the  fall,  247,  493. 

with  barbette  guns,  250,  491. 

with  casemate  gun.-,  249,  496. 

with  siege  guns,  245,  490. 

with  siege  mortars,  246,  492. 

Grape-shot,  49,  193. 
Grommet,  234,  419. 
Gun-cotton,  432,  615. 
Gun-lift,  described,  279,  539. 

storage,  314,  566. 

■  to  assemble  and  raise,  281,  540. 

to  mount  15-inch  gun,  282,  541. 

to  raise  a  weight,  281,  540. 

Gunner's  level,  53,  265;  105.  263;  1*9,   316;  150,  344;: 

161,  362. 
Gunner's  pouch,  55,  265;  78,  230,  IV. 
Gunner's  quadrant,  53,  264. 
Gunpowder,  barrels,  marks,  44,  186. 

sampling,  46,  182. 

to  open,  319,  516. 

caked,  to  break,  319,  516. 

cartridges,  bags,  47,  185. 


492  INDEX. 

[Nom— The  plain  figures  refer  to-  the  pages  of  this  volume.    The  f uU- 
xaced  figures  refer  to  paragraphs.] 

Gunpowder,  cartridges,  to  weigh  or  measure  charges,  188,  404. 

charges  to  destroy  vessels,  430,  614. 

demolition  by,  421,  669. 

grain,  size  of,  42,  18©;  43,  180. 

granulation  irregular,  (cannon,  mammoth,  musket,)  42, 

"    regular,  (cubical  and  molded,)  hexagonal,  42, 

180;  45,181.  ./-*,. 
pellet,  42,  18©;  46,  181. 

prismatic,  42,  18©;  46,  181. 

hardness,  43,  18©. 

incorporation,  44,  18©. 

initial  velocity,  43,  18©. 

inspection,  44,  18©. 

materials,  42,  18©. 

moisture  tests,  43,  18©. 

naval  classification,  46,  181. 

preservation,  316,  569. 

pressure,  47,  184;  147,  341. 

pressure-plug,  197,  413. 

qualities,  42,  18©. 

special,  44,  181 ;  45,  181. 

specific  gravitv,  43,  18©. 

storage,  317,  569;  318,  569;  390,  631. 

strain  on  guns,  43,  18©. 

tests,  flashing,  47,  183. 

■ of  moisture,  43,  18©. 

sampling,  46,  182. 


■  transportation,  318,  569. 

<2tans,  ammunition  for,  316,  568;  390,  631;  410,  660:  411. 
662;  413,  666;  416,  666. 

designation  of,  in  batteries,  82,  23©,  XXVIII. 

for  field-works,  371,  612. 

location  of,  388,  635. 

space  for,  368,  6©9. 

Gatling,  0.45-inch,  description,  170,  319;  177,  390. 

carriage,  181,  398. 

nomenclature,  180,  398. 

'-    precautions,  179,  391. 

service,  177,  391. 

to  assemble,  181,  4©©. 

to  take  apart,  181,  399. 

1-inch,  description,  170,  319;  171,  319. 


INDEX.  49S 

CNotk.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Guns,  Gatling,  1-inch,  nomenclature,  175,  386. 

service,  171,  380. 

storage,  314,  566. 

to  assemble,  176,  389. 

to  take  apart,  176.  388. 

Hotchkiss,  revolving,  description,  182,  400. 

suitable  for  block-houses,  400,  468. 


in  attack  of  positions,  403,  649 ;  404,  650. 

injuries  of,  132,  319;  297,  558. 

inspection  of,  299,  559. 

location  in  field-works,  388,  635. 

marks  on,  293,  553. 

on  skids,  295,  555. 

Parrott.    (See  below.) 

quantity  in  sieges,  411,  663. 

rifles  best  against  armor,  354,  590. 

selection  of,  for  besieging  batteries,  408,  65  V. 

siege,  care  of,  295,  551. 

space  for,  in  field-works,  388,  635. 

to  brown,  296,  557. 

to  disable,  309,  564. 

to  load  on  cars,  324,  572. 

what,  36,  144;  37,  146;  38,  154. 

Guns  of  U.  S.  system,  4.5-inch  rifle,  described,  2,  8 :  83,  231. 

carriages,  83,  231 ;  84,  231. 

dismount  carriage  and  limber,  222,  459. 

from  mortar-wagon,  214,  450. 

the  gun,  212,  448. 

with  the  gin,  246,  491. 

with  sling-cart,  254,  503. 

filing  to  traveling  bed,  208,  441. 

forward  or  backward,  206,  435. 

mechanical  manoeuvres,  204,  431. 

— mount  on  mortar- wagon,  214,  450. 

the  gun,  210,  441. 

with  the  gin,  245,  490. 

prepare  for  action,  210,  446. 

for  traveling,  210,  445. 

ranges,  84,  231. 

remove  short  roller  from  under  the  body,  208r 

439. 
the  chase,  207,  431. 


service  of,  83,  231. 


494  INDEX. 

[Note.— The  plain  figures  refer  to. the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 


Oims  of  U.  S.  system,  4.5-inch  rifle,  shift  carriages,  213,  449. 

from  carriage  to  mortar- wagon,  216, 

452. 

from  mortar-wagon  to  carriage,  217, 

453. 


short  roller  under  body,  207,  439. 

under  chase,  207,  436. 

side-lift  carriages,  209,  443. 
to  limber,  204,  433. 
to  unlimber,  205,  434. 
traveling  to  firing  bed,  208,  440. 


10-inch  rifled,  2,  8. 

12-inch  rifled,  2,  8. 

13-inch  smooth-bore,  2,  8;  2,  8n. 

15-inch  smooth-bore,  2,  8;  2,   8n. ;   119,   293;  126, 

306. 
carriages,  1 19,  293 ;  126,  306 ;  127,  308. 

dismount  by  blocks,  273,  534. 

the  gun.  274,  535 ;  275,  535 ;  276, 

535. 

lower  with  derrick,  291 .  550. 

mount  with  gun-lift,  282,  541. 

other  methods  mounting  and  dismounting,  278, 

537;  282,  541. 

ranges,  119,  293;  126,  306. 

raise  with  derrick,  290,  549. 

remove  chassis,  277,  536. 

replace  chassis,  2S7,  536. 

service  of,  120,  294;  126,  367. 


20-inch  smooth-bore,  2,  8;  2,  8n. 

<Juns  not  of  U.  S.  system,  but  in  service,  4.2-inch  (30  pdr.)  Par- 
rott, 2,  8. 
6.4-inch  (100  pdr. )  Parrott,  2,  8;  115,  288. 

ranges,  116.  288. 

service  of,  115,  288. 

8-inch  (200  pdr.)  Parrott,  2,  8;  115,  288. 

service  of,  115,  288. 

8-inch  rifled,  2,  8;  132,  319. 

carriages,  134-,  319;  135  n. ;  135,  320:  137, 

320. 
indications  of  injury,  132,  319. 

ranges,  133,  319;  134,  319. 

service  of,  carriage  1,  137,  321. 


INDEX. 


495 


•   [Not*.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  fall- 
laced  figures  refer  to  paragraphs.] 

■Guns  not  of  U.  S.  system,  but  in  service,  8-inch  rifled,  service  of, 

carriage  2,  141,  331. 
carriage  3,  142,  332. 

carriage  4,  144,  338. 

8-inch  smooth-bore,  2,  8. 

10-inch  smooth-bore,  2,  8 ;  108,  276. 

barbette  carriage,  109,  276. 

ranges,  109,  276. 

service  of,  109,  277. 

to  dismount,  282,  542 ;  283,  543 ;  284,  544. 

(300  pdr.)  Parrott,  2,  8 ;  115,  288. 

service  of,  115,  288. 

Gun-shields,  400,  648  ;  408,  657. 

■Guys,  formula  to  compute  strains  on,  474,  App. 

Hammer-wrench,  200.  416;  210,  444. 
Hammocks,  horse,  332,  516;  334,  577. 
Hand-barrows,  260,  512. 
Hand-carts,  259,  507. 

painting  and  storage,  314,  566. 

Handspikes,  56,  205;  86,  235,  236;  93,  256;  200,  41 7; 

201,417. 
Harbors,  defenses  of,  (see  Submarine  Mine?,)  343,  580;  388, 
636 ;  389,  636. 
arrangement  of  mines,  428,  673. 

lighting,  456,  602. 

position  of  mines,  427,  672. 

strength  of  batteries,  355,  592 ;  356,  593. 

submarine  mines,  346,  584;  425.  671 ;  426,  671. 

table  of  surface  currents,  458,  694. 

Harness,  care  of,  101,  258. 

for  siege-gun  batteries,  93,  255  ;  101,  258. 

Hitches,  234,  480;  235,  480. 
Holdfasts,  263,  519;  263,  521 ;  264,  521. 
Horse  batteries,  101,  259. 
Horses,  capabilities  of,  476,  App. 

care  of,  at  sea,  101,  258. 

disembarkations,  338,  578. 

embarkations,  328,  573;  329,  574;  333,  576. 

feeding,  at  sea,  328,  573. 

for  batteries  in  lines  of  works,  375,  616. 

for  siege-gun  batteries,  94,  256 ;  413,  665. 

hammocks  for,  at  sea,  332,  576;  334,  577. 


496  INDEX. 

[Note. — The  plain  figures  refer  to  the  pages  of  this  volume.    Tlie  lull- 
faced  figures  refer  to  paragraphs.] 

Horses,  medicines  for,  siege-gun  batteries,  101,  259. 

transportation  of,  by  rail,  322,  512. 

by  sea,  327,  573;  330,  515. 

Hotchkiss.    (See  Guns,  Hotchkiss.) 
Howitzers,  5.8-inch,  2,  8 ;  12S,  309. 

carriage,  128,  309. 

dismount  carriage,  271,  533. 

howitzer,  271,  533. 


mount  carriage,  273,  533. 

howitzer,  272,  533. 

ranges,  128,  309;  131,  318. 


8-inch,  (siege,)  2,  8;  102,  261. 

at  short  ranges,  404,  650. 

defined,  36,  144;  37,  141. 

doubly  charged  to  repel  assaults,  131,  3 IS. 

mechanical  manoeuvres,  208,  439. 

ranges,  103,  261 ;  222,  458. 

service  of,  102,  261. 

shells,  to  charge,  108,  2*75. 

target  practice,  187,  403. 

to  dismount,  218,  455. 

as  a  mortar,  221,  458. 

carriage  and  limber,  222,  459. 


to  mount,  219,  456. 

as  a  mortar,  220,  45*7. 

to  stand  on  its  muzzle,  218,  454. 
uses  in  ricochet  firing,  65,  214. 


Hurters,  6S,  217. 

Hydraulic  buffers,  69,  219 ;  135,  320. 

jacks.    (See  Jacks.) 

Ice  as  bridges,  342,  519. 

Impact,  effect  of  obliquity,  348,  586. 

phenomena,  352,  590. 

to  record  centre  of,  185,  402 ;  186,  402. 

Implements,  53,  203 ;  199,  416 ;  200,  416,  411 ;  201,  411- 
419. 

care  of,  295,  555 ;  312,  566. 

to  replace,  92,  250;  81,  230,  XXII. 

to  take  to  and  from  the  battery,  79,  230,  I;  81,  230* 

XXH;  201,419. 
Impressions  of  the  bore,  303,  562. 
Infantry,  cooperation  in  attack  of  positions,  405,  653. 


index.  51:3 

[Notjb.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Submarine  surface  currents,  458.  694. 

■  testing-room 8,  449,  689. 

tests  of  cables,  456,  693;  457,  693. 

to  fire,  450,  690;  451,  690;  452,  690;  453,  690. 

to  lay  cables,  445,  686. 

to  plant  the  mines,  447,  68* ;  448.  687. 

Supplies  for  preserving  artillery  material,  315,  567. 

for  siege-gun  batteries,  96,  258. 

of  ammunition  for  field-works,  316,  568;  390.  631; 

410,  660;  411,  662;  413,  666;  416.  666;  418, 
667. 

of  material,  315,  56 T. 

Swimming  horses,  338,  518. 
Sword  manual,  10,  46-48 ;  12,  59. 

Tables,  metric,  467,  App. 

miscellaneous,  470,  App. 

of  alloy 8,  472,  App. 

of  annual  armament  supplies,  315,  561. 

of  armor  penetration,  347.  586. 

of  atmospheric  pressure,  57,  206. 

of  drop  of  projectiles,  404,  650. 

of  harbor  surface  currents,  458,  694. 

of  metrical  equivalents,  469,  App. 

of  penetrations  of  parapets,  358,  595 ;  359,  595  ;  360, 

595. 


|  of  ranges.    (See  Rauges.) 

i  -   _         _  ■  — 


M\ 


of  slopes  for  parapets,  377,  619;  378,  619. 

of  strength  of  cordage,  237,  481. 

of  thickness  of  parapets,  362,  596. 

of  strength  and  weight  of  iron  chains,  241,  484. 

of  strength  of  cordage,  237,  481. 

of  U.  S.  artillery,  2,  8. 

of  weights  and  measures,  467,  App. 

of  weights  and  volumes  of  metals,  471  App. 

miscellaneous,  471,  App. 

woods,  471,  App. 

to  obtain  centre  of  impact,  186,  402. 


Tackles,  239,  483;  240,  484. 

power  gained  by,  241,  484. 

Tactics,  (see  Manoeuvres,  Mechanical,  and  Manoeuvres,  Tactical,) 

in  battalion  formation  and  skirmishing,  34,  ISO. 
Target  practice  and  targets,  183,  401 ;  191,  409. 

33 


514  INDEX. 

*  [NpTB.— The  plain  figures  refer  to  the  pages  of  this  volume.    The  foU- 
faced  fig  ares  refer  to  paragraphs.] 

Target,  floating,  190,  4©9. 
guns,  Gatling,  192,  410. 

sea-eoast,  189,  409. 

— siege,  184,  402 ;  185,  402 ;  186,  402. 

horizontal,  185,  402. 

howitzers,  siege,  187,  403,  404;  188,  405. 

mortars,  Coehorn,  188,  406. 

sea-eoast,  189,  401;  189,  408. 

siege,  187,  404 ;  188,  405. 


: plotting  results,  191,  409. 

presented  by  ships,  349,  581;  350,  588;  351,  589. 

record  of,  185,  402 ;  191,  409;  299,  559. 

Teams  in  sieges,  (see  Horses,)  413,  665. 

Telegraphic  communication,  importance  during  attacks,  406, 
654.  s 

in  defending  defiles,  418,  661. 

with  guard-boats  in  defending  submarine  mines,  456. 

692. 
Telemeters,  Boulong^s,  192,  411;  193,  411. 

Gautier's,  193,  412. 

one  for  each  siege  gun,  95,  251 ;  192,  409. 

Telephone.    (See  Telegraph.) 

Tests,  flashing,  of  powder,  47,  183. 

of  defective  guns,  307,  563. 

. of  gunpowder,  to  sample,  46,  182. 

of  submarine  mines  and  cables.  449,  689;  456,  693; 

457,693. 
Tete-de  pont,  416,  661;  418,  668. 
Time-fuses,  50,  191. 

Time  of  flight,  to  ascertain,  184.  402 ;  192,  409. 
Tompions,  294,  555. 
Tools,  intrenching,  413,  664. 
Torpedoes,  (see  Submarine  Mines,)  398,  646. 

defined,  425,  610. 

for  bridge  demolitions,  422,  669. 

fuses,  439,  619;  440,  619. 

Towns,  distance  of  defenses,  376,  611. 

Toy's  fuse,  422,  669. 

Trace-rope,  93.  256;  200,  416;  210,  444. 

Tracing  field-works,  379,  621. 

Trains,  hauling  ammunition  in  sieges,  413,  666:  416,  666. 

parking,  412,  663. 

Transportation  by  rail,  322,  512. 


INDEX.  615 

•  [None. — The  plain  figures  refer  to  the  pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Transportation  by  sea,  321,  511 ;  325,  573. 

disembarking,  335.  518. 

horses,  by  sen,  327,  513. 

ammunition  in  sieges,  413,  666;  414,  666. 

stalls,  sea  transports,  330,  515 ;  333,  516 ;  333,  511. 

weight  of  field  battery,  330,  514. 

Transports,  marks,  341,  516. 

Traverses,  376,  618;  38S,  635;  393,  638;  394,  638. 
Troops,  number  for  harbor  batteries,  245,  582;  368,  601; 

370,611;  374,614. 
Trucks,  casemate,  257,  506. 
garrison,  314,  566. 

store,  259,  509. 

wagon,  260,  514;  277,  536;  279,  538. 

Trunnion  beds,  66,  216;  294,  555. 

chains,  259,  508. 

gauge,  300,  560. 

rings,  314,  566. 

rule,  300,  560. 

sights,  62,  211 ;  168,  31*. 

squares,  300,  560. 


fn 


Trunnions,  84,  135 ;  294,  555. 

Unix)AD,  to,  81,  230,  XVI;  91,  241;  117,  289;  125,  304; 
153,  350;  164,  366. 

Velocity,  39,  166. 
Vent,  35,  142;  294,  555. 

to  inspect,  297,  558 ;  307,  563. 

Vent-cover,  79,  230,  IV. 

gauge,  300,  560. 

gimlet.  54.  205. 

piece,  36,  142. 

punch,  54,  205. 

searcher,  300,  560. 

stopped,  79,  230,  V ;  87,  23$. 

Verification  of  sights,  60,  208;  62,  211. 
Vessels,  armored.    ( See  Iron-clads.) 
Vital  points  of  iron-clads,  351,  589. 

Wagon,  mortar,  261,  515. 

Water-cap  fuse-plug,  50,  191. 

Water  caps,  preservation  of,  313,  566, 


516  INDEX. 

[Note. — The  plain  figures  refer  to  the' pages  of  this  volume.    The  full- 
faced  figures  refer  to  paragraphs.] 

Water  supply  during  sieges,  412,  663.  ! 
Way-planks,  270,  529. 
Weights  and  measures,  467,  App. 
and  volumes,  miscellaneous,  472,  App.                                  j 

of  alloys,  472,  App.  j 

oi  elongated  projectiles,  478,  App. 

of  iron  balls,  477,  App. 

of  metals,  471,  App. 

of  round  cast-iron,  478,  App. 

of  woods,  471,  App. 

of  field  artillery,  330,  574. 

of  troops  on  bridges,  341,  579. 

Wharves,  temporary,  335,  578;  341,  579. 

Windage,  38,  152. 

Wind  pressure,  57,  206 ;  56,  206 ;  192,  409. 

Wire  entanglements,  397,  644. 

Worm,  54,  205  ;  312,  566. 

Worming,  232,  418. 


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jPlate  19. 


Chase,  Del. 


See-M*.  202.203. 

.204.  207.  2.08. tit. 
J>a,vs.  426.427.433. 
436.4-39.448. 


ft-ATE  20, 


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fi-ATE  21. 


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0 


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2  21.2  23. 


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X. 


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Plate  27. 


■29. 


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Plate  31. 


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Plate  32. 


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Plate  39. 


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See -». 303.307.308. 
7>ctrs.  562. .  563. 


Plate  56. 


Fig'.  5. 


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See  -M*.327.329.  330. 

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Plate  63. 


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?IATE  65 


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Plate  61. 


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?LATE  73. 


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1        44-0.445. 
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630.686 


•Plate  75 


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