410 Mr. Mallet on the Physical Conditions 



'" In 1813,an engineering company of Lyons, named tlie St. Etienne Company, proposed 

 to the French Government to manufacture all the guns then wanted of forged iron. They 

 sent to Paris a specimen 8-pounder,'weighing 570 lbs. It was mounted upon a truck-carriage, 

 with solid wheels, 17 inches in diameter, and fired with 3 lbs. of powder. The recoil was 

 25 feet; with 4 lbs. of powder it was 37 feet. The gun sustained nine rounds without 

 injury ; but the material was not approved of by the French officers. Other pieces, of the 

 caliber of 16 and 24, were made; the mode of fabrication seemed to be this: — Upon a 

 tube, formed after the manner of a common fowling-piece, or gun-barrel, bands of iron 

 were welded, embracing the tube, but in a direction contrary to that of the fibres of the 

 tube, until the requisite size and strength were obtained. The gun was bored out to the 

 proper caliber, and the breech-piece screwed in and soldered to its place by silver solder, 

 which was esteemed the best. The different bands of iron were welded to each other, 

 and to the tube, by blows from the hand-hammer. 



" ' The inventor proposed to employ, in the fabrication of 24-pounders, &c., bars of 

 iron 12 feet long by 1 foot 8 inches, which, forged out into skelps, and converted into 

 bars thinned off at the side, were welded together over a maundrel, under blows of a trip- 

 hammer. The trunnions were welded to one of the (external?) bands. The bars used 

 were twisted; and they believed that, as the small arms manufactured were excellent, this 

 process aucmented the tenacity of the metal by a fourth ; and this was their secret.' 



" But, extending the manufacture on a great scale, could we hope that the metal shall 

 always be scrupulously chosen, and that a practised and observing eye shall always watch 

 over tlie degree of heat which the metal ought to have, in order to work to a uniform 

 solidity the prodigious quantity of welding necessary to perfect the piece ? When the gun 

 is fired, the imperfect weldings will open imperceptibly, and the damps will penetrate the 

 fissures, which, after a time, will cause the gun to crack, and form within the bore leafy 

 exfoliations, which, retaining the fire, will occasion accidents. In short, the irremediable 

 oxidation of the bore, in time of war, will so enlarge it, as to throw the piece out of service ; 

 and in time of peace they would require constant painting to prevent this oxidation." 



The objections to wroiight-iron guns are continued thus: — 



" 1st. They promptly destroy the carriages by the suddenness and extent of the recoil. 



" 2nd. They incommode greatly the troops by the length of the recoil. 



" 3rd. They will change their range greatly, by the continued and inevitable oxida- 

 tion of the bore. 



"4th. They enfeeble the 'moral' of the cannonier, by the continued apprehension of 

 their bursting. 



" ' In fact, these guns often burst, although the first pieces furnished by the Company 

 did not always burst. We have thus dealt at large upon the defects of wrought-iron guns, 



