Chapter VII: Part I: Section VII

SIEGE ARTILLERY.

1. How are siege-guns mounted?

Usually on travelling-carriages, with limbers.

2. Of what number and kind of pieces is a siege train composed?

This must altogether depend on circumstances; but the following general principles may be observed in assigning the proportion of different kinds and calibres, and the relative quantity of other supplies for a train of 100 pieces:

GUNS. { 24-pdr., about one-half the whole number, 50
{ 18-pdr. or 12-pdr., one-tenth, 10
HOWITZERS. 8-in. siege, one-fourth, 25
MORTARS. { 10-in. siege, one-eighth, 12
{ 8-in. siege, 3
STONE-MORTARS, { } 6
COEHORN MORTARS, {in addition to the 100 pieces,} 6
WALL PIECES, 40

[Sidenote: 37]]

CARRIAGES.

For 24-pdr. guns, and 8-in. howitzers, one-fifth spare, 90
For 18-pdr. and 12-pdr. guns, 12
For 10-in. mortars and stone-mortars, one-sixth spare, 21
For 8-in. mortars, 4
_Mortar-wagons_, 1 for each 10-in. mortar and bed, for each
stone mortar and bed, and for three 8-in. mortar and beds, 38
_Wagons_ for transporting implements, intrenching and miner’s
tools, laboratory tools and utensils and other stores,
each loaded with about 2,700 lbs., say, 140
_Carts_ (carrying balls, &c. on the march), 50
_Park battery-wagons_, fully equipped, 28
_Park forges_, “ “ 8
_Sling carts_, large, 5
_Do._ hand, 4

DRAUGHT HORSES.

For each gun and howitzer, with its carriage, 8
“ Spare gun-carriage, 6
“ Mortar wagon, 8
“ Battery wagon, 6
“ Forge, 6
“ Cart, 2
“ Sling-cart, large, 2
“ Spare horses, 1-10th
——————
Total, about 1,900 horses.

[Sidenote: 38]]

PROJECTILES AND AMMUNITION.

{ Round-shot, 800 to each 24-pdr.,
{ 1,000 to each 18 and 12 pdr.
For Guns. { Grape and canisters strapped, 20 rounds to each piece.
{ Spherical case strapped, 20 rounds to each piece.
{ Shells, 800 to each 8-in. howitzer.
FOR HOWITZERS. { Canisters strapped, 5 to each.
{ Spher. case strapped, 20 to each.

{ 600 shells to each 10-inch.
FOR MORTARS. { 860 “ “ 8-inch.
{ 200 “ “ Coehorn.

_Gunpowder_, in barrels, 500,000 lbs.

Computing for each 24-pdr. round-shot, one-third the weight of shot.
“ “ 18 and 12 pdr. round-shot, one-fourth the
weight of shot.
“ “ grape, canister and spherical case, one-sixth
the weight of shot.
“ “ round of howitzer ammunition, }
5 lbs. }
“ “ round 10-in. mortar ammunition, } including
7 lbs. } charge of
“ “ round 8-in. mortar ammunition, } shell.
3 lbs. }
“ “ round Coehorn mortar ammunition, ½ lb.
“ “ round stone mortar ammunition, 1 lb.

3. What is the best position for guns in order to make a breach?

On the glacis, within 15 or 16 feet of its crest; but if the foot of the revetment cannot be seen from thence, the guns must be placed in the covered way, within 15 feet of the counterscarp.

[Sidenote: 39]]

4. In what manner should the fire of siege guns be conducted in order to form a breach?

1st. Make a horizontal section the length of the desired breach along the scarp, at one-third its height from the bottom of the ditch, and to a depth equal to the thickness of the wall.

2d. Make vertical cuts through the wall, not farther than ten yards apart, and not exceeding one to each piece of ordnance, beginning at the horizontal section and ascending gradually to the top of the wall.

3d. Fire at the most prominent parts of the masonry left standing; beginning always at the bottom and gradually approaching the top.

4th. Fire into the broken mass with howitzers until the breach is practicable.

5. How long would it take to make a breach of 20 yards in length?

Breaches of more than 20 yards in length have been opened by way of experiment, and rendered practicable in less than ten hours, by about two hundred and thirty 24-pdr. balls and forty shells in one case, and by three hundred 18-pdr. balls and forty shells in another.

6. How many discharges can an iron gun sustain?

An iron gun should sustain twelve hundred discharges, at the rate of twelve an hour; but whatever may be the rate of fire, it is deemed unsafe after that number of discharges. As many as twenty an hour have been made for sixteen consecutive hours.

[Sidenote: 40]]