NAGY RE 
589 
THURSDAY, OCTOBER 21, 1886 
OUR GUNS 
Vv BERNE oh attempts are made to manage scientific 
matters by means of committees failure is sure to 
result. Some of our Continental friends, the French 
especially, are fond of working in pairs, and excellent 
results have been arrived at by such means, but the 
method does not appear suitable to the English intellect, 
hence all our great achievements in science have been 
attained by single individuals. As soon as a committee 
gets to work, darkness seems to fall over the intellects of 
its members, and not only are the most absurd blunders 
perpetrated, and errors of judgment committed, but they 
are persevered in long after outsiders have detected and 
exposed them. We need only mention the Longridge 
wire-gun and the Moncreiff carriage as instances of the 
defective judgment which kept back the introduction of 
these useful and original inventions for some thirty years. 
But the blindness of the Ordnance Committee, or of the 
Unknown Being who is responsible for our guns, is still 
more curious and distressing with reference to the strains 
which guns must be constructed to withstand. We look 
in vain for any information on this head from the recent 
reports of committees or from the lectures of their inspired 
representatives, while such information as we have reveals 
the fact that, at the time when our new breech-loaders 
were designed, the knowledge of pressures which the 
Unknown Designers had was absolutely erroneous, and 
that the errors were of so elementary a character that it 
requires no special knowledge of the subject to detect 
them. If the indicator-diagrams of a steam-engine, and 
a statement of the work performed by it, were laid before, 
at any rate, the two civil members of the Ordnance Com- 
mittee, with a request that the pressures in the cylinder 
should be investigated with a view to ascertaining whether 
they were correct, these gentlemen would, at once, com- 
pare the indicated power with the work done, and if 
the former were less than the latter they would, without 
hesitation, declare that the pressures said to have pre- 
vailed in the cylinder were toolow. Now, attached to the 
official drawing of the first 10-inch breech-loading gun was 
a pressure-curve purporting to represent one-fourth the 
bursting pressure when firing a projectile of 500 lbs, 
weight, and imparting to it a muzzle velocity of 2100 feet 
per second. The mean pressure, measured from this curve, 
is 8°8 tons per square inch, the travel of the shot in the 
bore is 22 feet, hence the work done by the powder would 
be 15,205 foot-tons. The muzzle energy of the shot is a 
little more, namely, 15,284 foot-tons. But besides the 
energy communicated to the shot, the 300 lbs. weight of 
powder gases have to be set in motion, the friction of the 
gas checks has to be overcome, rotation has to be im- 
parted to the shot, the atmosphere has to be displaced, 
and the aggregate of this work can be shown to amount 
to at least one-third of that required to drive out the shot, 
a fact which the pressures recorded in the experiments 
made with the 7iumderer gun clearly proved. Colonel 
Maitland, in his lecture on our new guns at the United 
Service Institution in June 1884, rightly pointed out that 
VOL. XXxIV.—No. 886 
the area bounded by the pressure-curve represented the 
work done in the bore; how is it, then, that it never 
occurred to any one on the Ordnance Committee to com- 
pare the work done with the effect produced? Such a 
comparison would have shown 20,400 foot-tons of work 
done by an indicator-diagram measuring only 15,205 foot- 
tons! The check pointed out should have been applied 
as a matter of common prudence, because it is notorious 
that then, as now, our direct knowledge of the pressure of 
powder gases in the bores of guns was very limited. 
We are aware that it has been explained that the 
pressure-curve we have been discussing does not repre- 
sent powder-pressures, but pressures one-fourth of those 
which would burst the gun; but such an explanation does 
not mend matters, for it reduces the factor of safety of 
the gun—already assumed at the dangerously low limit of 
four—to th ree, which no one, surely, would contend to be 
sufficient ! Se aang I 
-:We are obliged to revert to the question, Why has 
not an actual pressure-curve been made public, and why 
did not the Coldingwood Committee commence their 
report by showing that the 12-inch 43-ton gun was de- 
signed of sufficient strength? The answer, we are afraid, 
is that our gun-builders do not know what pressures they 
have to contend against, that our guns are being made 
by rule of thumb; in fact, their proportions are slowly 
arrived at by the costly method of trial and error. 
Again, Colonel Maitland, in his lecture, gives a diagram 
showing, graphically, the pressure resulting from firing 
quick-burning, medium, and slow-burning powders. We 
must assume, the curves being given for the purpose of 
comparison, that they represent the effects of the same 
weights of powder burned under exactly similar condi- 
tions ; therefore the areas of the figures bounded by the 
curves, as Colonel Maitland tells us, represent the work 
done in the gun, and measuring the areas of each curve 
up to only 14 calibres’ length of bore we find that the 
slow-burning p owder does more than twice the work of 
the medium-burning, and two and a half times that of the 
quick-burning powder! Surely Colonel Maitland would 
not wish us to draw such conclusions ; and yet they are 
necessarily deduced from a diagram which must have 
represented the views of the Ordnance Committee only 
two years ago, and after Capt. Noble had shown, in his 
admirable lecture on “The Heat-Action of Explosives,” 
delivered at the Institution of Civil Engineers, that the 
potential energy of all powders was very nearly the same ; 
a view recently indorsed by Sir W. Armstrong, who 
stated that rather more of the slowest-burning powder was 
required to produce a given ballistic effect. We venture 
to say that, had the questions in review been under the 
control of a single, competent, fully-responsible man; 
the anomalies which we have pointed out could never 
have arisen, the aid of practical mathematicians would 
have been invoked, and the warnings of Sir W. Arm- 
strong and others would not have been disregarded. 
The public, no doubt, is weary of the constant dis- 
cussion of past blunders, and the repeated allusions to 
them would be unjustifiable were it not for the vital 
bearing which these have on the future, and a most valu- 
able result will be obtained if our efforts, and those of 
other writers, should be the means of destroying our 
ce 
