SIR ANDREW NOBLE: RESEARCHES ON EXPLOSIVES. 



209 



Mark I (for which the country has been indebted to the labours of Sir F. ABEL and 

 Sir J. DEWAR), the modified cordite known as M.D., and a tubular nitrocellulose 

 known as R. R. Rottweil. 



The general results, which I need not say have necessitated much calculation, are 

 given in tables, but I think it necessary to give the results of a few experiments 

 worked out in full, these being a fair sample of the whole series. In each case I give 

 the reconciliation between the elements determined in the explosive and the same 

 elements found in the gases after explosion. 



Taking into account the fact that the explosives themselves are not always of 

 precisely the same composition, and also the nature of the experiments, the recon- 

 ciliation to which I have referred is a very great deal closer than I expected. 



It has been suggested to me more than once that the mixture of the gases might 

 not be homogeneous, that is, that tubes taken at different times from the explosion 

 vessel might not give the same analysis. I have not found this to be the case. Thus, 

 in an experiment where a charge of Rottweil R. R. was fired under a pressure of 

 20'5 tons per sq. inch (3125 atmospheres), and a tube of the resultant gases was 

 taken so soon as it was certain that all the air contained in the conducting tubes, &c., 

 was displaced, a second tube being taken 6 or 7 minutes later, the analysis gave for 

 the two tubes of permanent gases the following percentages : 



1st tube. 



2nd tube. 



C0 2 



CO 



H 



CH 4 



N 



28 '06 percentage volumes. 

 34-02 

 17-16 

 7-41 

 13-35 



28-02 percentage volumes. 

 33-92 

 17-00 

 7-40 

 13-66 



Taking now the data given by the explosion of a charge of 3 2 '6 8 grammes of M.D., 

 which was fired at a density of O'l under a pressure of G - 9 tons per sq. inch 

 (1051 '8 atmospheres), the resultant quantity of gas was 



27,486 cub. centims. at 16 0- 6 C., and under bar. pressure of 75T33 millims. 

 = 25,916 cub. centims. at C. and 751 "33 millims. 

 = 25,621 cub. centims. at C. and 760 millims. 



The quantity of water collected was 4136 grammes, equivalent to 5145'! cub. 

 centims. aqueous vapour at C. and 760 millims. 



The percentage results of the analysis of the permanent gases in volumes are 

 given in Column I., the total volumes in Column II, the percentage volumes, 

 including aqueous vapour, are shown in Column III., and the percentage weights of 

 the total gases in Column IV. 



VOL. ccv. A. 2 E 



