16 



Messrs. W. Macnab and E. Ristori. [May 10, 



the products of the number of calories by the volumes of gas, the 

 last three figures being suppressed in order to simplify the results. 



In the case of EC and SS a certain amount of mineral residue 

 was left, but this was not determined. 



Troisdorf leaves a slight, and Sifleite and BN a considerable, 

 carbonaceous residue, part of it adhering so tenaciously to the bomb 

 that an exact determination was not made. 



In the other experiments recorded in Tables I and II the degree of 

 accuracy of the results may be gauged by the fact that the average 

 weight of the products of explosion, calculated from the results found, 

 amounts to 99' 7 per cent, of the weight of the explosive fired, the 

 extreme limits being 10O5 and 98'9 per cent. 



In Table II the comparison of the pairs of results from explosives 

 made with lower and more highly nitrated nitro-cellnlose shows that 

 the use of the highly nitrated cellulose increases the quantity of 

 heat developed, and diminishes the volume of gas. The composition 



Table III. Showing the Heat developed by Explosives containing 

 Nitro-glycerin and Nitro-cellulose in different proportions. 



