The guns will be of the following calibers: ⅓ of 18 Prs.—⅓ of 12 Prs.—and ⅓ of 24, 9, and 4 Pounders in equal proportions. If the place does not possess any very extraordinary means of defence, it will be very respectably supplied with 800 rounds of ammunition per gun for the two larger calibers, and 900 for each of the others.
Gun Carriages—⅓ more than the number of guns.
Mortars—About ¼ the number of guns in the three first classes; and ⅕ or ⅙ in the other classes. Of these ⅖ will be 13 or 10 inch mortars, and the rest of a smaller nature.
Howitzers—¼ the number of mortars.
Stone Mortars—⅒ the number of guns.
Shells—400 for each of the 10 and 13 inch mortars, and 600 for each of the smaller ones.
Beds for mortars—⅓ to spare.
Carriages for howitzers—⅓ to spare.
Hand Grenades—4 or 5000 for the two first classes; 2000 in the three following classes; and from 1500 to 600 in the three last classes.
Rampart Grenades—2000 for the first class; 1000 for the four following classes; and 500 for the sixth class; none for the two last.
Fuzes—¼ more than the number of shells.
Bottoms of wood for stone mortars—400 per mortar.
Sand Bags—500 for every piece of ordnance in the large places, and ¼ less in the small ones.
Handspikes—10 per piece.
Tackle Falls for gins—1 for every 10 pieces to spare.
Musquets—1 per soldier, and the same number to spare.
Pistols, pairs—½ the number of musquets.
Flints—50 per musquet, and 10 per pistol.
Lead or Balls for small arms—30 pounds per musquet.
Powder for Small Arms—5 pounds for every musquet in the garrison, including the spare ones.
The above proportions are taken from Durtubie’s Manuel De l’Artilleur.
The following method of regulating the management of the artillery, and estimating the probable expenditure of ammunition in the defence of a fortified place, is extracted from a valuable work on fortification lately published at Berlin. It is particularly applied to a regular hexagon; the siege is divided into three periods, viz.
1st. From the first investiture to the first opening of the trenches, about 5 days.
2d. From the opening of the trenches to the effecting a lodgement on the glacis, about 18 days.
3d. From this time to the capitulation, about 5 days.
First Period. Three guns on the barbette of each bastion and on the barbettes of the ravelins in front of the gateways, half 24 Prs. and half 18 Prs.[4] three 9 Prs. on the barbette of each of the other ravelins.
Twelve 12 Prs. and twelve 4 Prs. in reserve.
One 13 inch mortar in each bastion.
Six of 8 inch in the salient angles of the covert way.
Do. in reserve.
Ten stone mortars.
The 12 Prs. in reserve, are to be ranged behind the curtain, on whichever side they may be required, and the 4 Prs. in the outworks; all to fire en ricochet over the parapet. By this arrangement, the whole of the barbette guns are ready to act in any direction, till the side of attack is determined on; and with the addition of the reserve, 49 pieces may be opened upon the enemy the very first night they begin to work upon the trenches.
The day succeeding the night on which the trenches are opened, and the side to be attacked determined, a new arrangement of the artillery must take place. All the 24 and 18 Prs. must be removed to the front attacked, and the other bastions, if required, supplied with 12 Prs. The barbettes of the bastions on this front may have each 5 guns, and the 12 18 prs. may be ranged behind the curtain. The six mortars in reserve must be placed, two in each of the salient angles of the covert way of this front, and with those already there, mounted as howitzers,[5] to fire down the prolongations of the capitals. Three 4 pounders in each of the salient places of arms of the ravelins on the attacked fronts, to fire over the palisading, and five 9 Prs. in the ravelin of this front. This arrangement will bring 47 guns, and 18 mortars to fire on the approaches after the first night; and with a few variations will be the disposition of the artillery for the second period of the siege. As soon as the enemy’s batteries are fairly established, it will be no longer safe to continue the guns en barbette, but embrazures[6] must be opened for them; which, embrazures must be occasionally masked, and the guns assume new directions, as the enemy’s fire grows destructive; but may again be taken advantage of, as circumstances offer. As the enemy gets near the third parallel, the artillery must be withdrawn from the covert way to the ravelins, or to the ditch, if dry, or other favorable situations; and, by degrees, as the enemy advances, to the body of the place. During this period of the siege, the embrazures must be prepared in the flanks, in the curtain which joins them, and in the faces of the bastions which flank the ditch of the front ravelins. These embrazures must be all ready to open, and the heavy artillery mounted in them, the moment the enemy attempts a lodgement on the glacis.
Every effort should be made to take advantage of this favorable moment, when the enemy, by their own works, must mask their former batteries, and before they are able to open their new ones.
The expenditure of ammunition will be nearly as follows:
First period of the siege—5 rounds per gun, per day, with only half the full charge, or ⅙ the weight of the shot, and for only such guns as can act.
Second period—20 rounds per gun, per day, with ⅙ the weight of the shot.
Third period—60 rounds per gun, per day, with the full charge, or ⅓ the weight of the shot.
Mortars—At 20 shells per day, from the first opening of the trenches to the capitulation.
Stone Mortars—80 rounds per mortar, for every 24 hours, from the establishment of the demi parallels to the capitulation; about 13 days.
Light, and Fire balls—Five every night, for each mortar, from the opening of the trenches to the eighth day, and three from that time to the end
These amount to about
700 for guns.
400 for mortars.
1000 for stone do.
This proportion and arrangement is however made upon a supposition, that the place has no countermines to retard the progress of the besiegers, to a period beyond what is abovementioned; but the same author estimates, that a similar place, with the covert way properly countermined beforehand, and those countermines properly disputed, may retard a siege at least 2 months; and that if the other works be likewise effectually countermined and defended, the siege may be still prolonged another month.
The above proportion is therefore to be further regulated, as the strength of the place is increased by these or any other means. These considerations should likewise be attended to, in the formation of an estimate of ammunition and stores for the siege of a fortified place. See Carriage, Platform, Park, and the different natures of artillery, as Gun, Mortar, Howitzer, &c.
The small arms ammunition is estimated by this author as follows:
¼ of a pound of gunpowder, or 10 rounds per day, per man, for all the ordinary guards.
1¼ lbs. or 50 rounds per man, per 12 hours, for all extraordinary guards.
⅝ of a pound, or 25 rounds for every man on picket, during the period of his duty.
AXLETREES—See the word Carriages.