Calculations proving the comparative Economy of the Rocket Ammunition,
both as to its Application in Bombardment and in the Field.
So much misapprehension having been entertained with regard to the
expense of the Rocket system, it is very important, for the true
understanding of the weapon, to prove, that it is by far the cheapest
mode of applying artillery ammunition, both in bombardment and in the
field.
To begin with the expense of making the 32-pounder Rocket Carcass,
which has hitherto been principally used in bombardments, compared with
the 10-inch Carcass, which conveys even less combustible matter.
£. _s._ _d._
{Case 0 5 0
Cost of a 32-pounder {Cone 0 2 11
Rocket Carcass, complete {Stick 0 2 6
for firing in the present {Rocket composition 0 3 9
mode of manufacture. {Carcass ditto 0 2 3
{Labour, paint, &c. 0 5 6
------------
£1 1 11
------------
If the construction were more systematic, and elementary force used
instead of manual labour, the expense of driving the Rocket might be
reduced four-fifths, which would lower the amount to about 18_s._
each Rocket, complete; and if bamboo were substituted, which I am
endeavouring to accomplish, for the stick, the whole expense of each
32-pounder Carcass Rocket would be about 16_s._ each.
Now as the calculation of the expense of the Rocket includes that of
the projectile force, which conveys it 3,000 yards; to equalize the
comparison, to the cost of the spherical carcass must be added that of
the charge of powder required to convey it the same distance.
£. _s._ _d._
Cost of a 10-inch { Value of a 10-inch spherical
Spherical Carcass, { carcass 0 15 7
with a proportionate { Ditto of charge of powder, 0 6 0
charge of powder, &c. { to range it 3,000 yards
{ Cartridge tube, &c. 0 1 0
------------
£l 2 7
------------
So that even with the present disadvantages of manufacture, there is an
actual saving in the 32-pounder Rocket carcass itself, which contains
more composition than the 10-inch spherical carcass, _without allowing
any thing for the difference of expense of the Rocket apparatus, and
that of the mortar, mortar beds, platforms, &c._ which, together
with the difficulty of transport, constitute the greatest expense of
throwing the common carcass; whereas, the cost of apparatus for the
use of the Rocket carcass does not originally exceed £5; and indeed,
on most occasions, the Rocket may, as has been shewn, be thrown even
without any apparatus at all: besides which, it may be stated, that
a transport of 250 tons will convey 5,000 Rocket carcasses, with
every thing required for using them, on a very extensive scale; while
on shore, a common ammunition waggon will carry 60 rounds, with the
requisites for action. The difference in all these respects, as to the
10-inch spherical carcass, its mortars, &c. is too striking to need
specifying.
But the comparison as to expense is still more in favour of the Rocket,
when compared with the larger natures of carcasses. The 13-inch
spherical carcass costs £1. 17_s._ 11½_d._ to throw it 2,500 yards; the
32-pounder Rocket carcass, conveying the same quantity of combustible
matter, does not cost more than £1. 5_s._ 0_d._--so that in this case
there is a saving on the first cost of 12_s._ 11½_d._ Now the large
Rocket carcass requires no more apparatus than the small one, and the
difference of weight, as to carriage, is little more than that of the
different quantities of combustible matter contained in each, while the
difference of weight of the 13-inch and 10-inch carcasses is at least
double, as is also that of the mortars; and, consequently, all the
other comparative charges are enhanced in the same proportion.
In like manner, the 42-pounder Carcass Rocket, which contains from 15
to 18 lbs. of combustible matter, will be found considerably cheaper in
the first cost than the 13-inch spherical carcass: and a proportionate
economy, including the ratio of increased effect, will attach also to
the still larger natures of Rockets which I have now made. Thus the
first cost of the 6-inch Rocket, weighing 150 lbs. and containing 40
lbs. of combustible matter, is not more than £3. 10_s._ that is to
say, less than double the first cost of the 13-inch spherical carcass,
though its conflagrating powers, or the quantity of combustible matter
conveyed by it, are three times as great, and its mass and penetration
are half as much again as that of the 10-inch shell or carcass. It is
evident, therefore, that however extended the magnitude of Rockets
may be, and I am now endeavouring to construct some, the falling
mass of which will be considerably more than that of the 13-inch
shell or carcass, and whose powers, therefore, either of explosion or
conflagration, will rise even in a higher ratio, still, although the
first cost may exceed that of any projectile at present thrown, on a
comparison of effects, there will be a great saving in favour of the
Rocket System.
It is difficult to make a precise calculation as to the average
expense of every common shell or carcass, actually thrown against the
enemy; but it is generally supposed and admitted, that, on a moderate
estimate, these missiles, one with another, cannot cost government
less than £5 each; nor can this be doubted, when, in addition to the
first cost of the ammunition, that of the _ordnance_, and _the charges
incidental to its application_, are considered. But as to the Rocket
and its apparatus, it has been seen, that the _principal expense_ is
that of the first construction, an expense, which it must be fairly
stated, that the charges of conveyance cannot more than double under
any circumstances; so that where the mode of throwing carcasses by
32-pounder Rockets is adopted, there is, at least, an average saving
of £3 on every carcass so thrown, and proportionally for the larger
natures; especially as not only the conflagrating powers of the
spherical carcass are equalled even by the 32-pounder Rocket, but
greatly exceeded by the larger Rockets; and the more especially indeed,
as the difference of accuracy, for the purposes of bombardment, is not
worthy to be mentioned, since it is no uncommon thing for shells fired
from a mortar at long ranges, to spread to the right and left of each
other, upwards of 500 or even 600 yards, as was lately proved by a
series of experiments, where the mortar bed was actually fixed in the
ground; an aberration which the Rocket will never equal, unless some
accident happens to the stick in firing; and this, I may venture to
say, does not occur oftener than the failure of the fuze in the firing
of shells. The fact is, that whatever aberration does exist in the
Rocket, it is distinctly seen; whereas, in ordinary projectiles it is
scarcely to be traced--and hence has arisen a very exaggerated notion
of the inaccuracy of the former.
But to recur to the economy of the Rocket carcass; how much is not the
saving of this system of bombardment enhanced, when considered with
reference to naval bombardment, when the expensive construction of the
large mortar vessel is viewed, together with the charge of their whole
establishment, compared with the few occasions of their use, and their
unfitness for general service? Whereas, by means of the Rocket, every
vessel, nay, every boat, has the power of throwing carcasses without
any alteration in her construction, or any impediment whatever to her
general services.
So much for the comparison required as to the application of the Rocket
in bombardment; I shall now proceed to the calculation of the expense
of this ammunition for field service, compared with that of common
artillery ammunition. In the first place, it should be stated that the
Rocket will project every species of shot or shell which can be fired
from field guns, and indeed, even heavier ammunition than is ordinarily
used by artillery in the field. But it will be a fair criterion to make
the calculation, with reference to the six and nine-pounder common
ammunition; these two natures of shot or shell are projected by a small
Rocket, which I have denominated the 12-pounder, and which will give
horizontally, and _without apparatus_, the same range as that of the
gun, and _with apparatus_, considerably more. The calculation may be
stated as follows:--
£. _s._ _d._
{Case and stick 0 5 6
12-pounder Rocket {Rocket composition 0 1 10½
{Labour, &c. 0 2 0
--------------
£0 9 4½
--------------
But this sum is capable of the following reduction, by substituting
elementary force for manual labour, and by employing bamboo in lieu of
the stick.
£. _s._ _d._
{Case and stick 0 4 0
[B]Reduced Price {Composition 0 1 10½
{Driving 0 0 6
-------------
£0 6 4½
-------------
[B] And this is the sum that, ought to be taken in a general
calculation of the advantages of which the system is
_capable_, because to this it _may_ be brought.
Now the cost of the shot or spherical case is the same whether
projected from a gun or thrown by the Rocket; and the fixing it to the
Rocket costs about the same as strapping the shot to the wooden bottom.
This 6_s._ 4½_d._ therefore is to be set against the value of the
gunpowder, cartridge, &c. required for the gun, which may be estimated
as follows:--
£. _s._ _d._
6-pounder Amm’n. {Charge of powder for the 6-pounder 0 2 0
{Cartridge, 3½_d._ wooden bottom, 0 0 7¼
{ 2½_d._ and tube, 1¼_d._
-------------
£0 2 7¼
-------------
£. _s._ _d._
9-pounder Amm’n. {For the 9-pounder charge of powder 0 3 0
{Cartridge, 4½_d._ wooden bottom, 0 0 8¼
{ 2½_d._ and tube, 1¼_d._
-------------
£0 3 8¼
-------------
Taking the average, therefore, of the six and nine-pounder ammunition,
the Rocket ammunition costs 3_s._ 2¾_d._ a round more than the common
ammunition.
Now we must compare the simplicity of the use of the Rocket, with the
expensive apparatus of artillery, to see what this trifling difference
of first cost in the Rocket has to weigh against it. In the first
place, we have seen, that in many situations the Rocket requires no
apparatus at all to use it, and that, where it does require any, it
is of the simplest kind: we have seen also, that both infantry and
cavalry can, in a variety of instances, combine this weapon with their
other powers; so that it is not, in such cases, _even to be charged
with the pay of the men_. These, however, are circumstances that can
_in no case_ happen with respect to ordinary artillery ammunition; the
use of which never can be divested of the expense of the construction,
transport, and maintenance of the necessary ordnance to project it,
or of the men _exclusively_ required to work that ordnance. What
proportion, therefore, will the trifling difference of first cost, and
the average facile and unexpensive application of the Rocket bear to
the heavy contingent charges involved in the use of field artillery? It
is a fact, that, in the famous Egyptian campaign, those charges did not
amount to less than £20 per round, one with another, _exclusive_ of the
pay of the men; nor can they for any campaign be put at less than from
£2 to £3 per round. It must be obvious, therefore, although it is not
perhaps practicable actually to clothe the calculation in figures, that
the saving must be very great indeed in favour of the Rocket, in the
field as well as in bombardment.
Thus far, however, the calculation is limited merely as to the bare
question of expense; but on the score of general advantage, how is not
the balance augmented in favour of the Rocket, when all the _exclusive_
facilities of its use are taken into the account--the _universality_
of the application, the _unlimited_ quantity of instantaneous fire
to be produced by it for particular occasions--of fire not to be by
any possibility approached in quantity by means of ordnance? Now to
all these points of excellence one only drawback is attempted to be
stated--this is, the difference of accuracy: but the value of the
objection vanishes when fairly considered; for in the first place, it
must be admitted, that the general business of action is not that of
target-firing; and the more especially with a weapon like the Rocket,
which possesses the facility of bringing such quantities of fire on any
point: thus, if the difference of accuracy were as ten to one against
the Rocket, as the facility of using it is at least as ten to one in
its favour, the ratio would be that of equality. The truth is, however,
that the difference of accuracy, for actual application against troops,
instead of ten to one, cannot be stated even as two to one; and,
consequently, the compound ratio as to effect, the same shot or shell
being projected, would be, even with this admission of comparative
inaccuracy, greatly in favour of the Rocket System. But it must still
further be borne in mind, that this system is yet in its infancy, that
much has been accomplished in a short time, and that there is every
reason to believe, that the accuracy of the Rocket may be actually
brought upon a par with that of other artillery ammunition for all the
important purposes of field service.