564 TRANSACTIONS OF THE AMERICAN INSTITUTE. 



Chairman. — Is there any gentleman present who can give us 

 the origin of rifling? 



A gentleman said it could be found in the history of Chinese 

 antiquities. 



The Chairman alluded to the ancient mode of projecting things 

 by the Greeks and Romans. 



Mr. Garvey remarked that in the instance of David killing 

 Goliath there must have been a rifling motion given to the stone. 

 He explained the motion of rifling which was given to the Arm- 

 strong gun. At the breech it occupies one position, and when 

 discharged it occupies another. He also explained very fully the 

 theory by which rifled guns shoot more accurately than smooth 

 bored pieces. It is the corkscrew motion given to the ball which 

 causes its accuracy of aim. He thought that anything that em- 

 ployed lead in rifling should not be used much. He wondered at 

 artillery being used as now constructed, as after a few shots were 

 fired the guns became dangerous to those using them. He would 

 advise artillery men to fire away their cannon and keep the ram- 

 rod. That is, to use a solid bar of metal for a gun and tubes for 

 projectiles. This is a form of gun he himself had devised. He 

 also stated that it required a good deal of force to give the rifling 

 motion to a ball while inside the gun, but it required a very 

 small force to keep up that motion after it had left the gun. 



Mr. Haskell. — Frederick Newbury, of Albany, has patented a 

 ball which consists of two balls together with an oil patch be- 

 tween. All that is intended to come in contact with the rifle is 

 the patch, the lead not coming in contact with it at all. 



Chairman. — ^What are the balls made of? 



Mr. Haskell. — They are made of lead. 



Mr. Stetson. — The expansive force of burning gunpowder has 

 been judged from some experiments to be so great as 200,000 

 lbs. to the square inch. But this only obtains when it is abso- 

 lutely confined. In practice, the force by a ball in a rifled or 

 other arm cannot be assumed to be nearly as great. The velocity 

 of a projectile is capable of approximate measurement. He (Mr. 

 Stetson), had timed the velocity of one of Hotchkiss' balls on the 

 day of the trial before the Mexican officers at Flushing, in 1859, 

 and found the ball occupied seventeen seconds in flying about 

 four miles. 



The Chairman. — Why do you use a long ball with a flat end ? 



Mr. Stetson. — Because the resistance of the air is less. A 



