1890.] Sir Frederick Ahel on Smokeless Explosives. 7 



WEEKLY EVENING MEETING, 



Friday, January 31, 1890. 



Sir Feederick Bramwell, Bart. D.C.L. F.R.S. Honorary Secretary 

 and Vice-President, in the Chair. 



Sir Frederick Abel, C.B. D.C.L. D.Sc. F.RS. V.P.B.L 



Sirtokeless Explosives. 



The production of smoke which attends the ignition or explosion of 

 gunpowder is often a source of considerable inconvenience in con- 

 nection with its application to naval or military purposes, its employ- 

 ment in mines, and its use by the sportsman, although occasions not 

 unfrequently arise during naval and military operations when the 

 shroud of smoke produced by musketry or artillery fire, has proved 

 of important advantage to one or other, or to both, of the belligerents 

 during different periods of an engagement. 



Until within the last few years, however, but little, if any, 

 thought appears to have been given to the possibility of dispensing 

 with or greatly diminishing the production of smoke in the applica- 

 tion of fire-arms, excepting in connection with sport. The inconve- 

 nience and disappointment often resulting from the obscuring effects of 

 a neighbouring gun-discharge, or of the first shot from a double- 

 barrel arm, led the s^^ortsman to look hopefully to gun-cotton, 

 directly after its first production in 1846, as a probable source of 

 greater comfort and brighter prospects in the pursuit of his pastime 

 and in his strivings for success. 



A comparison between the chemical changes attending the 

 burning, explosion, or metamorphosis of gun-cotton and of gunpowder, 

 serves to explain the cause of the production of smoke in the latter 

 case, and the reason of smpkelessness in the case of gun-cotton. 

 Whilst the products of explosion of the latter consist exclusively of 

 gases, and of water which assumes the transparent form of highly- 

 heated vapour at the moment of its production, the explosive sub- 

 stances classed as gunpowder, composed of mixtures of saltj)etre, or 

 another nitrate of a metal, with charred wood or other carbonised 

 vegetable matter, and with variable quantities of sulphur, furnish pro- 

 ducts, of which very large proportions are not gaseous, even at high 

 temperatures. Upon the ignition of such a mixture, these products 

 are in part deposited in the form of a fused residue, which constitutes 

 the fouling in a fire-arm, and are in part distributed, in an extremely 

 fine state of division, through the gases and vaj)ours developed by the 

 explosion, thus producing smoke. 



In the case of gunpowder of ordinary composition, the solid pro- 

 ducts amount to over fifty per cent, by weight of the total products 



