NITROGEN BODIES OF MODERN CHEMISTRY. 209 



with a single grain the combustion is transferred from grain to grain, 

 audthe whole quantity of carbon and sulphur is consumed in the oxygen. 



Nevertheless, gunpowder, though compounded with all possible care, 

 though triturated and incorporated with the most scrupulous attention, 

 can never acquire that perfect blending which may be attained by the 

 introduction of combinations of atoms into the structure of organic for- 

 mulie. 



As intimate and uniform an incorporation of the atoms as occurs in 

 the nitrogen bodies can never be effected by the mechanism of powder- 

 mills ; and this alone indicates the importance of the nitrogen com- 

 pounds. 



Not among the earliest of those bodies, it is true, but a very recent 

 descendant from them, and first brought into notice by the celebrated 

 chemist Schoubein, is gun-cotton. Gun-cotton is ordinary cotton ni- 

 trogeuized. Cotton is chemically called cellulose, vegetable cellulin, 

 vegetable fibrin. Vegetable fibrin has the formula — 



Fi.-. U 



Cg Hg O3 > .^ 

 U2 i ^' 



00 





000 



In the middle we see the union of the carbon atoms to be firm ; at 

 the ends comparatively weak. Now if, step by step, we replace the 

 hydrogen with nitrogen compounds, with nitryl, we have trinitrocel- 

 lulose, wherein these atoms of hydrogen are replaced by nitryl, and 

 we have before us gun-cotton, whose formation was effected by this 

 substitution of nitryl radicals N O2 for hydrogen. 



The manufacture of gun-cotton is extremely simple. We require 

 only the so-called nitro-sulphuric acid, which isiu common use. Thereare 

 two limits in compounding tliis acid. We may mix equal parts of good 

 Nordhausen acid, or Saxon or Bohemian oil of vitriol, and ot good 

 faming nitric acid, or three parts of Nordhausen acid and two parts of 

 nitric acid ; or two parts of Nordhausen acid and three of red fuming 

 nitric acid. A mixture with either of these proportions produces a 

 serviceable nitro-sulphuric acid, which has received the trivial name of 

 ifulminic acid from its use in the manufacture of fulminating compounds. 



In mixing the brown oil of vitriol with red nitric acid there occurs a 

 moment when the mixture of the two acids is nearly colorless. This is 

 the state in which the compound is most available. It must be efiect- 

 ually cooled, if possible in a freezing mixture composed of three parts 

 snow and one part epsom salts or common cooking-salt j or, at all events, 

 Us 



