involved in the Construction of Artillery. 



375 



enormous charges, and without injury pave the loss of a trunnion struck off in recoil, 

 appeared to have a good deal a greater tliickness than usual in bronze guns: it was very 

 short. On the principles announced in the text then, those guns, possessed of an enormous 

 surplus strength, are safe enough ; but upon guns so proportioned no argument whatever 

 can rest as to the generally advantageous character of steel guns. 



A very different result awaited a much larger gun, of cast-steel, made and proved last 

 year at Woolwich. The magnificent forging for it — which, from observation, I can state to 

 have been of steel of extremely fine quality — was supplied by IMr. Krupp, of Essen. It 

 was about lOi feet long, and as much as 17 inches diameter at the larger end. The boring 

 and turning were effected, and the construction of the gun, — of which a longitudinal 

 section is given below, — -was under the direction of some of the autliorities at Woolwich. 



«^;:>^ 





The steel forging — originally intended, it would appear, for a 32-pounder — was bored 

 out to an 8-inch gun, and, when completed, the diameter round the powder chamber was 

 about 16 inches, leaving the thickness here not more than 4 inches or 4^ inches, or about 

 half a caliber. 



The finished steel gun only weighed about 2^ tons; and, to carry out the established 

 system of absorbing recoil by mere crude weight, a cast-iron jacket, or " chemise," was 

 made to slip over it, of no less than 7 tons weight. This was bored at the bottom to fit 

 the steel gun, which was here secured to the chemise, by the wrought-iron breech-ring 

 screw, passing through the chemise, and being tapped into the steel. The steel gun, except 

 here, had a free space of about an inch all round between it and the chemise ; but, at the 

 mouth of the latter, the gun was supported and kept central by a wrought-iron circular 

 ring flange, bolted to the mouth end or face of the chemise. 



Tlie gun itself, therefore, derived no support, or reinforce, whatever, from this un- 

 wieldy mass of cast-iron round it, and on to which the trunnions were cast. 



The vent was bored out right through both chemise and gun, to about 1^ inches dia- 

 meter, and a steel or wrought-iron vent was tapped through both, and rigidly connected 

 them at this point at least. 



3 c2 



