CHEMICAL SCIENCE. 247 



N 0.5 = 3 C Os + X + K S, 100 grains would furnish 130 80 cubic inches of gas 

 at the temperature of 32 Fahr., and under an atmospheric pressure of twen- 

 ty-nine of mercury. 



By mcas- 



10 grains of gunpowder. Yields by Combustion. By weight, lire 13 086 



cubic ius. 



Carbon . . 0-1332 ) ( Carbonic acid . . . . 0-4885 = 9-823 



Sulphur .. 0-1184 J = < Sulphide of potassium 0-4078 = 

 Nitre .. 07484) (Nitrogen .. .. 01037 = 3263 



The volume of the gas would be the same if the carbon were converted 

 into carbonic oxide instead of carbonic acid ; and if, instead of nitrogen 

 being liberated, binoxide of nitrogen were formed ; and since the gas pro- 

 duced by the explosion of gunpowder consists, as a general rule, solely of 

 carbonic acid, carbonic oxide, nitrogen, and nitric oxide, with mere traces of 

 hydrogen and sulphuretted hydrogen, it would appear that 131 cubic inches 

 is the largest volume of gas that 100 grains of normal gunpowder could pos- 

 sibly furnish. However, the experiments of Gay-Lussac, and those of most 

 subsequent investigation, indicate, on the contrary, that the volume of gas 

 furnished by the explosion of gunpowder under the ordinary atmospheric 

 pressure is much greater than that which could be furnished according to the 

 above view. Messrs. Bunsen and Schischoif, of Heidelberg, have, therefore, 

 directed their attention to this important point in theoretic artillery, and have 

 published a memoir on the subject, which not only furnishes the first com- 

 plete solution of the problems involved in the theory of the explosion of 

 gunpowder, but which is particularly rich in new methods of investigation 

 and analysis. The authors, from want of time, were obliged to confine their 

 researches to one kind of powder, and to its combustion under the ordinary 

 atmospheric pressure. The methods employed, however, will apply, with 

 slight modifications, to other cases. The powder gave, on analysis 



Saltpetre 78-99 



Sulphur 9-84 



( Carbon 7-69 



no^Ko J Hydrogen 0-41 



Carbon 'j Oxygen 3-07 



( Ash trace. 



100.00 



A preliminary qualitative analysis gave the following substances as solid 

 products of the combustion of the powder employed: 1. sulphate of pot- 

 ash, 2. carbonate of potash, 3. hyposulphite of potash, 4. sulphid of potas- 

 sium, 5. hydrate of potash, 6. sulphocyanid of potassium, 7. nitrate of pot- 

 ash, 8. carbon, 9. sulphur, 10. carbonate of ammonia. The gaseous products 

 were 1. nitrogen, 2. carbonic acid, 3. carbonic oxide, 4. hydrogen, 5. sulphid 

 of hydrogen, and occasionally 6. nitric and nitrous oxide. By means of a 

 particular apparatus, the authors were able to prepare the solid residue of the 

 explosion, the smoke or vapor which accompanies it, and the gaseous pro- 

 ducts, and to analyze each separately. For the elaborate details of the anal- 

 ysis we must refer to the original memoir. The solid residue was found to 

 contain 



Sulphate of potash 5G-62 



Carbonate of potash 27-02 



Hyposulphite of potash 7-57 



Sulphid of potassium ... .*. 1-06 





*v 



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