1847.] Memoranda on Explosive Cotton. 181 



Two days' exposure are sufficient in the month of February, to bring 

 the cotton into as dry state as is required for its use with ordnance or 

 small arms. 



Steam or hot water heat may be used for the drying with perfect 

 safety with suitable apparatus. But unless this be in every respect 

 properly constructed, the danger of making a large quantity of cotton 

 is too serious to be trifled with. I have also dried cotton successfully 

 in vacuo, and by the immediate contact of masses of quick-lime, but 

 it is needless at present to occupy the pages of this Journal with de- 

 scriptions of the arrangements, by which these facts can be practically 

 applied. 



When dry the cotton is next to be carded ; or loosened out by the 

 native bowstring apparatus. 



The expressed acid may be used for the remaining 50 tolas of the 

 100. It will however be generally found that after 40 tolas have been 

 immersed, the acid begins to corrode or pulp the cotton, producing a 

 new series of compounds, chiefly oxalic acid, formic acid, and sugar. 



The same series of operations above described is gone through with 

 the second acid, and the resulting cotton kept apart. 



After drying, it is found that the 100 tola weight of cotton has 

 increased to 114 to 120, according to the care with which the process 

 has been conducted. 



The process thus performed affords two qualities of explosive cotton. 



The first 50 tolas may be designated 1st or best quality. 



The product of the 2d expressed acid and the second 50 tolas of 

 cotton should be marked 3d or worst quality. 



If these be mechanically mixed by carding or the bow-string, the 

 mixture may be called 2d quality. 



The acid mixture which after cooling was Sp. gr. 1667 before use, 

 after once having been used is of Sp. gr. 1687. Twice used its density is 

 1691. The acid once used measures 1 80 fluid ounces and by distillation 

 yields £ its bulk of nitric acid, Sp. gr. 1480 ; the acid twice used yields 

 Jth its bulk of nitric acid, Sp. gr. 1400. By prolonged boiling in platinum 

 or glass vessels, the pulpy cotton in the mixture is decomposed with 

 copious effervescence of carbonic acid and nitric oxyde gases ; when this 

 terminates and the acid in the boiler begins to blacken, the concentra- 

 tion has proceeded far enough, and on cooling the original sulphuric 



