102 ANNUAL OF SCIENTIFIC DISCOVERT. 



application as a substitute for gunpowder. — Journal of Frank- 

 lin Institute, Oct., 1806. 



GUN-COTTON. 



M. Blondeau makes the following communication to the 

 Academy of Sciences, Paris. If gun-cotton of good quality be 

 exposed for aljout four hours to the action of the vapor of ammo- 

 nia, it will soon assume a yellow tint, indicating its combination 

 ■with the ammonia; and, after being dried, it furnishes a powder 

 which is unalteralde at ordinary temperatures, and even unde- 

 eomposable at 212° (Fahr.), and possesses au explosive force 

 greater than that of ordinary gun-cotton. 



Gun-cotton has not hitherto been received with much f;ivor by 

 artillerists, but some recent experiments of Mr. Whitworth go 

 far to prove that, under certain circuanstances, it may be used with 

 advantage. He linds that a ciiarge made up of gunpowder and 

 gun-cotton, the former material being exploded lirst, gives a 

 lower trajectory, and will also admit of a lighter gun being used. 

 By this means, the great explosive j^ower of gun-cotton is com- 

 bined with the advanUiges due to the gradual action of ortlinary 

 powder. 



GUN-PAPER. 



Mr. G. S. jSIelland, of Lime street, London, who has distin- 

 guished himself among British makers of lire-arms, has i-ecently 

 invented a " gun-paper," to supersede the old gunpowder. The 

 invention consists in impregnating jjaper with a composition 

 formed of chlorate of potasii, 9 jjarts ; nitrate of potash, 4^ ; 

 prussiate of potash, 3i ; powdered charcoal, 3^ ; starch, l-12th 

 part; chromate of potash, 1-lGth part; and water 79 parts. 

 These are mixed, and boiled during one hour. The solution is 

 then ready for use, and the paper passed in sheets through the 

 solution. The saturated paper is now ready for manufacturing 

 into the form of a cartridge, and is rolled into compact lengths 

 of any required diameter. These rolls may also be made of re- 

 quired lengths, and cut up afterward to suit the charge. After 

 rollmg, the gun-paper is dried at 212° Fahr., and has the appear- 

 ance of a compact grayish mass. Experiments have been made 

 with it, and it has been reported favorably of as a perfect suljstitute 

 for gunpowder, superseding gun-cotton and all other explosives. 

 It is said to be safe, alike in manufacture and in use. The paper is 

 dried at a very low temperature. It may be freely handled with- 

 out fear of explosion, which is not produced even by percussion. 

 It is, in fact, only exploded by contact with fire, or at equivalent 

 temperatures. In its action it is quick and powerful, having, in 

 this respect, a decided advantage over gunpowder. Its use is 

 unaccompanied by the greasy residuum always observable in gun- 

 barrels that have been fired with gunpowder. Its explosion 

 produces less smoke than from gunpowder ; it is said to give less 

 recoil, and it is less liable to deterioration from dampness. It is 

 readily protected from all chance of damp by a solution of xyloidin 

 in nitric acid. 



