220 SIR ANDREW NOBLE: RESEARCHES ON EXPLOSIVES. 



C. 

 Hence maximum temperature reached . . . . 2 '6 18 



Less 0-581 



2'037 

 Add correction . 0'012 



2'049 



TT ., ,., 4680x2-049 10QQ K 



Hence units of heat = = 1239 '5. 



7737 



The repeat Experiment No. 1391 gave 



TT ., , 4680x2-060 



Units of heat = ^^ = 1246'2. 



To illustrate the remark I made as to increase of accuracy when taking the calorimetric 

 observations at the higher densities, I give the whole of the observations on this point 

 with Mark I cordite. Thus, at the density of 0'05 the three observations were, 

 respectively, 1265'!, 1303'0, 1248'8, or a mean of 1272'3 units. With density O'l the 

 three observations were 1275"8, 1240'5, 12357, or a mean of 12507 units. Density 

 0-15 gave 12597, 1247'2, 12427, or a mean of 1249'9. With density 0'20, 1245'2, 

 1246-5, 1241-0, or a mean of 1244'2. Density 0'25, 1246'2, 1239'5, and 1241'3, giving 

 a mean of 1242'3. 0'3 density gave 1276*9, 1280'0, 1264'0, mean 1273'6 : for 0'4, 

 1305-0 and 1294'3 or 12997 mean, and for 0'45, 1326'3 and 1320'0 or mean 1323'2. 



We are now in a position to give in a tabular form the result of the series of 

 experiments on the three explosives fired under a variety of densities and pressures, 

 and with regard to which the essential constants have been determined. 



These tables give : 



(1.) The densities under which the various charges were fired. 



(2.) The volumes of permanent gases generated at C. and 760 millims. of 

 barometric pressure per gramme of explosive. 



(3.) The total volume of gas per gramme, aqueous vapour being included. 



(4.) The percentage volumes of permanent gases. 



(5.) The percentage volumes of the total gases. 



(6.) The percentage weights of the total gases. 



(7.) The pressures at each density in tons per sq. inch. 



(8.) The same pressures in atmospheres. 



(9.) The units of heat determined, the water being fluid. 

 (10.) The imits of heat, water being gaseous. 



(11.) The specific heat of the products of explosion for each density. 

 (12.) The comparative temperatures of explosion determined by dividing the 



units of heat (water gaseous) by the specific heats in (11). 



(13.) The comparative potential energy, the highest energy determined being 

 taken as unity. 



