50 TEAK-BOOK OP FACTS. 



point, — that strength was the important desideratum. He said that 

 a large number of Sir W. Armstrong's large guns bad lately burst. 

 Mr. E. Cowper agreed with Captain Blakeley. Sir W. Armstrong's 

 guns that were said to have burst were simply cast-iron guns 

 hooped. For small arms, he was of opinion that the Lancaster 

 rifle was very successful. The bullet was of lead, and did not jam, 

 as was sometimes the case with the iron shot in the larger guns. 

 If Captain Blakeley's plan were adopted, he thought that for 10/. 

 any gun in the service might be made sufficiently strong. Mr. 

 Dennis thought that Captain Blakeley's method of giving strength 

 was right. 



IMMENSE AMERICAN CANNON. 



The Scientific American publishes the following: — "A Cannon, 

 weighing 35 tons, has been successfully cast at the Fort Pitt 

 Foundry, Pittsburgh, under the superintendence of Lieutenant 

 Rodman, of the Ordnance Department. This is stated to be the 

 largest cannon in the world. The casting is fifty inches in diameter, 

 and nineteen feet five inches long. Seventy-eight thousand pounds 

 of metal were melted for it in three reverberatory air furnaces within 

 four and a half hours after the fires were lit. The furnaces were 

 tapped in succession, and the iron run in separate channels into a 

 common reservoir, from which it passed into the mould — the latter 

 being filled within twenty-one minutes after the first tap. The 

 mould was a ponderous structure, and was placed vertically in a pit 

 prepared for the purpose. The gun has been named the ' Floyd,' in 

 compliment to the Secretary of War, whose zeal for the improve- 

 ment of artillery prompted this laudable experiment in gunnery. 

 The model of the gun was designed by Lieutenant Rodman, and 

 made under his supervision from a plan of which he is the inventor, 

 for casting guns hollow, and cooling them by circulating a stream of 

 water through the interior of the core. The cold water enters at the 

 top, passes down through a pipe in the centre of the core, and is 

 discharged at the bottom of the hollow part ; and then, passing 

 up through the core, becomes heated, and is discharged at the top. 

 It circulates a constant stream at the rate of forty gallons per minute, 

 and is continued until the casting becomes cool. The drawings, 

 patterns, and computations were made by Mr. N. It. Wade, junior 

 member of the firm of Knapp, Hudd, and Co. The moulding and 

 casting were conduct) ! DJ Mr. J. Kaye, and Joseph Marshal] melted 

 the iron. The ease, regularity, and thorough success with which the 

 different processes were conducted were astonishing, and sufficiently 

 manifested the extraordinary practical skill and judgnientof all con- 

 cerned in the operation." 



UOOnrei IUFI.KD CANNOX. 



Mr. Lynau. Thomas's Rifled Cannon, the largest rifled weapon 

 ever made, has been tried with complete success at Sim. burynesaj. 

 This cannon weighs upwarda of 6 tone, and fires • shot of 174 lbs. 



weight, with a charge of powder of no less than a quarter of a 



