42 ANNUAL OF SCIENTIFIC DISCOVERY. 



grooves of the barrel, without essentially altering the shape known to 

 be best to secure to it velocity and a rotary movement in the direction 

 of its longest axis. The stem is a cylinder of steel, tempered at the 

 end upon which the ball rests, and screw-threaded at the other end for 

 a length of 1 centimetre ; the diameter .009 millimetre, and the 

 height above the breech .038 mil. The barrel has 4 grooves, with the 

 inclination of 2 metres in one revolution; breadth of groove 7 mil. ; 

 the depth varying from 3 mil. at the breech to 1.5 mil. at the muzzle 

 of the musket. A special hausse, with a hinge-joint, is attached about 

 4 inches in front of the cone, admitting of three fixed sights, and with 

 a movable slide for higher elevations. Gen. Tournemine told me that 

 the altered musket had been fired at 1,200 metres, placing GO balls in 

 the butt in the 100 ; the carbine the same at 800 ; and the artillery 

 carbine (having only 23 inches length of barrel) placed 56 per cent, 

 in the butt at 400 metres. Far inferior results would commend 

 strongly the introduction of a principle which secured them. The 

 shape of the ball (every line of which is said to have been established, 

 as it now is, upon special trial) can be best judged of from the one 

 presented herewith ; its weight is 47.5 grammes. The service charge 

 for the musket is 4.5 grammes (for the artillery carbine 2 grammes 

 less) ; for blank cartridges 7 grammes are used. As 6.30 grammes 

 are necessary to fill the space around the stem, the charge of 7 is or- 

 dered, that the rod may never touch the stem in loading. The vacant 

 space between the powder and the ball secures room enough for any 

 ordinary accumulation of dirt in long-continued firing, and no injury 

 has resulted from it to any of the arms tried. Ball-cartridges are made 

 with an extra piece of paper, forming a cup, to contain the powder ; 

 the ball and this cup are then enveloped in the ordinary folds of the 

 cartridge-paper, and the ball end dipped in grease. In loading, the 

 powder is poured into the barrel, the ball inverted, and inserted in 

 the bore, all the paper torn off and thrown away, and the ball rammed 

 home. Six cartridges are bundled together (with eight caps, in a 

 special cylinder). In the alteration of old guns to this new plan, a 

 stem of the proper size is screwed into the original breech-pin, and 

 the old barrel grooved as above stated. To avoid the necessity of 

 using the stem, a recent proposition has been made to use a ball 

 charged at its lower extremity with powder (percussion, I believe), 

 which, exploding with the charge of the gun, would swell out the 

 circumference of the ball sufficiently to fill the grooves of the barrel. 

 Experiments with this ball have been perfectly successful. 



" In connection with this subject I will mention a novelty, exhibited 

 at the national exhibition at Paris by Berger of St. Etienne. It is a 

 musket-lock, where the number of parts is reduced to three. Its ex- 

 ternal appearance is the same as the present French musket-lock, so 

 that the same lock-plate could be used. Reversing the existing action 

 of the lock (where the tumbler is attached to the hammer, making ne- 

 cessary a sear-spring to equipoise the pressure of the main-spring upon 

 the nose of the tumbler), to the hammer is attached a piece, acting as 

 the sear ; and the end of the main-spring has on it the notches usually 

 on the tumbler. The upper arm of the spring has on the end a pro- 



