542 MM. Pelouze and Maurey on the New Methods 



in which 3 equivalents of water are replaced by 3 equivalents of 

 nitric acid, so that General von Lenk's gun-cotton would be a 

 trinitrocellulose. This is the name by which they have de- 

 scribed it. 



They have further expressed the opinion that the pyroxyle 

 prepared with less proportions of acids, as at Bouchet, might 

 present a different composition. 



One of us had determined in 1847 the composition of gun- 

 cotton, and had represented it by the formula 



C 24 H 17 17 5N0 5 . 



We had therefore first to determine whether the product then 

 investigated was different from that of Lenk's gun-cotton, and 

 in case the Bouchet cotton proved chemically identical with the 

 Lenk cotton, what ought to be its true formula. 



We believe we have bestowed on these researches the greatest 

 pains, and we think we have overcome all the difficulties which 

 the combustion of gun-cotton presents. We may at once say 

 that we have established the identity, chemically speaking, of 

 the gun-cotton of General Lenk and of that from Bouchet, and 

 we have arrived at a formula only differing by one equivalent 

 of tfftter from that adopted in 1847. 



rh<3 new formula, 



C 24 H 18 O 18 5N0 5 , 



corresponds to the following numbers : — 



Carbon . . 



. . 25-00 



Hydrogen . 



. . 3-13 



Oxygen . . 



. . 59-72 



Nitrogen . 



. . 12-15 



100-00 



It is so close to the old formula, C 24 H 17 O 17 5N0 5 , that analysis 

 alone would not have justified the change. Our choice is based 

 on the proportion of the yield. In fact the new formula sup- 

 poses a yield of 177*78 of gun-cotton for 100 of cotton, while the 

 old one merely corresponds to a yield of 175. Our direct experi- 

 ments, related previously, have led to the number 178. 



All the gun-cottons we analyzed were previously washed in a 

 mixture of ether and alcohol (which removed from them some 

 thousandths of fatty matters and of soluble substances), then 

 dried for several hours in an oven at a temperature between 40° 

 and 50°. All had the same composition. 



Our formula, 



C 24 H 18 18 5N0 5 , 



ought to give, as gaseous products of the decomposition of gun- 



