5 
He then lays down that since the breaking strain of good steel is more than 
double its elastic limit, therefore if the strain is below that limit this constitutes 
a sufficient factor of safety. The gun will therefore be strong enough if made of 
steel with an elastic limit of 27 tons and a breaking strain of 54 tons per square 
inch.} 
General Wille winds up with a sort of half admission that the foregoing is not 
quite satisfactory, as an extra high pressure might strain the metal beyond the 
elastic limit and permanently weaken the gun. He says “If a higher factor of 
safety be required, we must trust to the discoveries of the future; and then goes 
onto hint at a card up his sleeve—a novelty either in steel aking or gun making 
—-which he is not at liberty to publish. 
(2.) Five writers consider the gun carriage too light to stand the recoil. 
One points out that it will be strained 2°6 times as severely as the German 
field carriage. Another critic caleulates that a gun of 2095 lbs. and carriage of 
1650 would be required to stand the recoil. A third approves of the Griison 
carriage but finds fault with General Wille’s details, such as the muzzle traversing 
gear. Others simply condemn the carriage as impossible. 
In reply, General Wille compares the various existing field carriages (without 
buffers) and finds the average strain on them to be 230 foot lbs. per pound of gun 
and carriage. 
Next, he adduces calculation, result of experiment and the admissions of some 
of his critics to shew that: (a) the hydraulic buffer reduces the strain on the 
carriage 60 per cent.,? and (b) that nitro powder reduces it a further 15 per cent. 
Applying these reductions to the strain on his own carriage, he finds it is about 
the same as on the average field carriage. 
He finally states that he has seen a number of rounds fired from a carriage of 
the same weight as his which had not even a buffer, yet which stood a strain equal 
to that of the recoil of his gun. 
(3.) One writer approves generally of General Wille’s design, but considers 
the length of the gun impracticable. He proposes a 3°15 inch 164 1b. gun, 
weighing 926 lbs. and 73 feet long, to give a muzzle velocity of 1870 f.s. with a 
powder pressure of 14-7 tons. 
General Wille points out that such a gun is so little in advance of present 
field guns as to be hardly worth making, as it will certainly be obsolete in a year 
or two. 
(4.) The same writer concurs with General Wille as to the value of high 
velocity in extending the zone of shrapnel effect, but points out as an objection to 
a flat trajectory the increased difficulty in ranging a battery, as with General 
Wille’s gun. An error in elevation will give double the present error in range. 
General Wille replies that this is only a half truth, as the flat trajectory does not 
require such accurate ranging as the curved trajectory. or instance, with his 
gun, if you include the target in a 400 yards bracket you can proceed at once to 
time fuze at the mean of the bracket, since a further correction of 100 yards makes 
no practical difference in the height of burst of the shrapnel. 
He further proves by comparison of 50°/, rectangles that the length of the 
rectangle does not increase with the velocity. For instance a Griison field gun 
fired at muzzle velocities of 1500 fs. and 2100f.s. gave at 1000 yards® rectangles 
1 See * Treatise on Service Ordnance ’93,” p. 448, giving tests of “‘ high” steel up to 40 tons on 
yielding and 71 on breaking. 
2 Our G.C.F. people do not seem to agree with General Wille or they would have made the 
12-pr. buffer carriage 60 per cent. lighter than Mark I. 
It certainly seems unnecessarily heavy. 
3 Metres in the original. 
57B 
