214 



SIR ANDREW NOBLE: RESEARCHES ON EXPLOSIVES. 



Multiplying again by 



Add H 2 



Totals 

 In the R.R. nitrocellulose 



Difference 



= 7'947, we have the weights :- 



-1-28 



+ 1-29 



+ 0-32 



-0-33 



In the reduction of the experiments hitherto considered, it has not been necessary 

 to make any correction to the quantity of gas, as the weight of the gases sufficiently 

 accurately represents the weight of the explosive experimented on, but it occasionally 

 happens, especially at high pressures, that, at the moment of firing, a puff of gas 

 escapes, the leak, however, being generally only momentary, the explosion vessel 

 becoming later perfectly tight. In these cases of course the weight would be in 

 defect, but in a few cases the weight of the gases was in excess, and I proceed to 

 show how these experiments were dealt with. 



Experiment 1417. At a density of 0'45 a charge of 143'91 grammes of M.D. 

 cordite, giving a pressure of 43'22 tons per square inch (6588'2 atmospheres), 

 generated 98,231-9 cub. centims. at C. and 760 millims. pressure; the water 

 collected was 15'59 grammes = 19,384'0 cub. centims. The analysis of the perma- 

 nent gases in volumes gave : 



Now if to the weights given in Column III. we add the weights of water, it will 

 be found that the total weight is 1'44 grammes greater than the charge actually 

 employed. The volume of the gases has therefore been reduced to 97,589'5 cub. 

 centims., thus giving 676'3 cub. centims. of permanent gases or 810'6 cub. centims. 

 total gas for each gramme exploded. 



