Necessary considerations in forming an estimate for this service.
The force, situation, and condition of the place to be besieged;
whether it be susceptible of more than one attack; whether lines of
circumvallation or countervallation will be necessary; whether it
be situated upon a height, upon a rocky soil, upon good ground, or
in a marsh; whether divided by a river, or in the neighborhood of
one; whether the river will admit of forming inundations; its size
and depth; whether the place be near a wood, and whether that wood
can supply stuff for fascines, gabions, &c.; whether it be situated
near any other place where a depot can be formed to supply stores for
the siege. Each of these circumstances will make a very considerable
difference in proportioning the stores, &c. for a siege. More artillery
will be required for a place susceptible of two attacks, than for the
place which only admits of one. For this last there must be fewer
pieces of ordnance, but more ammunition for each piece. In case of
lines being necessary, a great quantity of intrenching tools will be
required, and a numerous field train of artillery. In case of being
master of any garrison in the neighborhood of the besieged town, from
whence supplies can readily be drawn, this must be regarded as a
second park: and too great a quantity of stores need not be brought at
once before the besieged place. The number of batteries to be opened
before the place must determine the number of pieces of ordnance; and
on the quantity of ordnance must depend the proportion of every species
of stores for the service of the artillery.
There must be a battery to _enfilade_ every face of the work to be
besieged, that can in any way annoy the besiegers in their approaches.
These batteries, at least that part of them to be allotted for
guns, need not be much longer than the breadth of the rampart to be
enfiladed, and will not therefore hold more than 5 or 6 heavy guns;
which, with two more to enfilade the opposite branch of the covert
way, will give the number of guns for each ricochet battery. As the
breaching batteries, from their situation, effectually mask the fire of
the first or ricochet batteries, the same artillery generally serves
for both. Having thus ascertained the number of heavy guns, the rest of
the ordnance will bear the following proportion to them:
_Mortars._—From 8 inch to 13 inch, about ⅓.
_Small Mortars._—About ¼.
_Heavy Howitzers._—About ⅛.
The fewer natures of ordnance which compose the demand the better,
as a great deal of the confusion may be prevented, which arises from
various natures of ammunition and stores being brought together.
_The Carriages for the Ordnance are generally as follows_:
For 24 Prs. ⅚ the number of guns.
For Mortars, ⁸/₉ the number of mortars.
For Howitzers, ¾ the number of howitzers.
For _Stone_ Mortars, ⁶/₇ the number of mortars.
_Ammunition for the Ordnance._
24 Prs.——At 1000 rounds per gun.
Mortars, howitzers, and stone mortars,
at 800 rounds per piece of ordnance.