COMPOSITION OF GUNPOWDER, ETC. 190 



The amount of recoil which can be pleasantly borne by the 

 shoulder, will vary somewhat with the weight of the gun. 

 Thus, a light one of 61bs. will show perhaps a recoil, 

 according to the machine, of only 651bs., yet it will be more 

 unpleasant to shoot than another weighing 81bs., which recoils- 

 TOlbs. according to the same test. According to iny ex- 

 periments, I believe that with guns of the usual weight and 

 bore, that is, from Tibs, to T|lbs. for 12-bore, and a quarter 

 of a pound less for each diminution of size, the recoil, in 

 order to be pleasantly borne, should not on any account exceed 

 TOlbs. Those who are particular in this matter will prefer 

 to have one showing lOlbs. or even 151bs. less, but to get the 

 highest degree of penetration, the amount of recoil above 

 fixed must be incurred. 



The chief causes of undue recoil, are the disproportion of 

 the projectile to the powder, the excessive quantity of the 

 latter, inordinate opening of the barrel, roughness of the metal, 

 or fouling of the barrel, and lastly, a want of sufficient weight 

 of the whole gun to give vis inertice to resist the force of the 

 explosion. Some of these vary with the state of cleanness in 

 which the gun is, and with the charge with which it is 

 loaded, but the others continue the same under all cir- 

 cumstances. 



COMPOSITION OF GUNPOWDER, GUNCOTTON, AND OTHER 

 EXPLOSIVE MIXTURES USED WITH THE GUN. 



In order to force the projectile to its proper destination, 

 two explosive substances only have as yet been usefully 

 applied namely, gunpowder and guncotton ; but there are 

 others which are used merely to procure ignition by percus- 

 sion in some shape or other, being introduced into small 

 metal capsules denominated percussion caps, or into some 

 similar convenient vehicle such as Lancaster's copper disk. 



Gunpowder is composed, in all cases, of three substances 

 nitre, sulphur, and charcoal but the proportions adopted 

 by different makers vary to some extent. In a work of this 

 nature, intended for the sportsman only, it is scarcely neces- 

 sary to enter upon the new chemical combinations which 

 follow the explosion of this potent agent, but it may be men- 



