420 Mr. F. A. Abel on the Stability of Gun-cotton, [April 4, 



10. Water acts as a most perfect protection to gun-cotton (except when 

 it is exposed for long periods to sunlight), even under extremely severe 

 conditions of exposure to heat. An atmosphere saturated with aqueous 

 vapour"suffices to protect it from change at elevated temperatures ; and wet 

 or damp gun-cotton may be exposed for long periods in confined spaces to 

 100° C. without sustaining any change. 



Actual immersion in water is not necessary for the most perfect preserva- 

 tion of gun-cotton ; the material, if only damp to the touch, sustains not 

 the smallest change, even if closely packed in large quantities. The organic 

 impurities which doubtless give rise to the very slight development of acid 

 observed when gun-cotton is closely packed in the dry condition, appear to 

 be equally protected by the water ; for damp or wet gun-cotton, which has 

 been preserved for three years, has not exhibited the faintest acidity. If 

 as much water as possible be expelled from wet gun-cotton by the centri- 

 fugal extractor, it is obtained in a condition in which, though only damp 

 to the touch, it is perfectly non-explosive ; the water thus left in the mate- 

 rial is sufficient to act as a perfect protection, and consequently also to 

 guard against all risk of accident. It is therefore in this condition that 

 all reserved stores of the substance should be preserved, or that it should 

 be transported in large quantities to very distant places. If the proper 

 proportion of sodic carbonate be dissolved in the water with which the 

 gun-cotton is originally saturated for the purpose of obtaining it in this 

 non-explosive form, the material, whenever it is dried for conversion into 

 cartridges, or employment in other ways, will contain the alkaline matter 

 required for its safe storage and use in the dry condition in all climates. 



Although some experiments, bearing upon the different branches of in- 

 quiry included in this memoir, are still in progress with a view to the 

 attainment of additional knowledge of the conditions which regulate the 

 stability of gun-cotton, it is confidently believed that the results arrived at 

 amply demonstrate that the objections which have been of late revived, 

 especially in France, against the employment of gun-cotton, on the ground of 

 its instability, apply only in a comparatively slight degree to the material 

 produced by strictly pursuing the system of manufacture perfected by von 

 Lenk — that, as far as they do exist, they have been definitely traced to certain 

 difficulties in the manufacture of pure gun-cotton which further experi- 

 mental research may, and most probably will, overcome — but that, in the 

 meantime, these objections are entirely set aside by the adoption of two 

 very simple measures, against the employment of which no practical diffi- 

 culties can be raised, and which there is every reason to believe must secure 

 for this material the perfect confidence of those who desire to avail them- 

 selves of the special advantages which it presents as an explosive agent. 



The nature of the decomposition of gun-cotton when exploded under 

 different conditions is now under investigation by me ; and the results 

 arrived at will, I trust, be communicated before long to the Royal Society. 



