276 On the Chemical Composition of Gun-Cotton. 



Carbonic acid 0'420 ers."! . • • r^.-mr, t.^« 



Carbonic oxide 0-198 ... jco'^taimng 0-200 carbon. 



Nitrogen . . 0-178 ... 



Water . . . 0-200 ... 

 0-996 ... 

 which differs but little from the result obtained by the im- 

 perfect combustion, and agrees completely as far as the nitro- 

 gen is concerned. 



Since reading this paper an article has appeared in the 

 Comptes Re7ulus of the Academy of Sciences at Paris, dated 

 23rd November 1846, that Messrs. Fordos and Gelis had ob- 

 tained from gun-cotton a cyanic compound ; this tends to 

 confirm our discovery of the presence of cyanogen among the 

 gaseous products. 



A view may be taken of the composition of gun-cotton 

 agreeing with the ultimate results, but arranging the elements 

 differently, by subtracting 1 atom of oxygen from the nitric 

 acid and adding it to the lignin ; gun-cotton would then be 

 formed of nitrous acid + oxide of lignin ; this new oxide may 

 possess alkaline properties, and thus account for the singular 

 fact of the non-acidity of gun-cotton : we intend to try if we 

 can establish this composition by experiment. 



We have tried the action of a small galvanic battery in de- 

 composing the gun-cotton, but without any decided results ; 

 on the first vigorous action of the battery, reddened litmus 

 paper was made blue in the negative cell, but as the power 

 of the battery subsided this effect disappeared. As the result 

 of several trials, it does not appear that gun-cotton is suscep- 

 tible of explosion by the discharge from a Leyden phial. 



In conclusion, we think proper to express our dissent 

 from the mechanical view taken by Mr. Crum of the nature 

 of gun-cotton. He considers that the tubular structure which 

 the microscope developes in cotton accounts for the admission 

 of nitric acid into its vessels, but does not explain why it 

 should not get out again on washing ; and he thinks that the 

 preservation of its fibrous organization is inconsistent with 

 its chemical combination with nitric acid. Now the fact is, 

 that when cotton is immersed in a mixture of equal measures 

 of sulphuric and nitric acids it combines with the latter only, 

 to the exclusion of the former, which shows a peculiar affinity 

 inconsistent with any mechanical view of the action. 



