392 
ME. F. A. ABEL’S CONTRIBUTIONS TO 
portion of the gun-cotton contained in one of three closely adjacent wooden store-sheds 
or magazines, containing together about 13 tons of the material, was unquestionably 
due primarily to the spontaneous decomposition of some very impure material, the 
existence of which in one of those stores was clearly demonstrated in the subsequent 
inquiry. This, and the gun-cotton stored with it, was packed in strong boxes of the 
same kind as those used in the above experiments. Several unusually hot days had 
preceded that of the explosion, and the contents of the boxes, confined in these wooden 
store-sheds, which they filled almost completely, must have become very warm 
throughout. A large volume of flame, apparently enveloping these sheds, was described 
by eye-witnesses at a considerable distance as having been observed for a short but very 
distinct interval previous to the explosion ; and there appears no doubt that the ignition 
of some portion of gun-cotton must have been immediately followed by the inflamma- 
tion of the entire contents of one box, the flame rapidly penetrating to other boxes, and 
in a very brief space of time determining the explosion of some portion of the confined 
gun-cotton in the manner already described. The explosion not only of the entire 
contents of the one shed but also of the two in close proximity was the inevitable 
result, the small brick partitions which separated the sheds from each other affording 
no impediment to the almost instantaneous transmission of the explosion. Among the 
buildings which were ignited by the flame, or burning debris from this principal explo- 
sion, there were two small store-houses or packing-sheds, containing gun-cotton packed 
in a number of boxes of very light construction as compared with the packing-cases 
already alluded to : these sheds and their contents were entirely consumed without any 
explosion. But there was a third of the same kind which contained some of the strong 
boxes filled with gun-cotton, and this, after having been some considerable time in flames, 
exploded with great violence. 
In my Memoir “ On the Stability of Gun-cotton ” '* I demonstrated by numerous 
experiments and by the results of observations upon a large scale, and extending over 
some considerable time, that water acts as a most perfect preservative of gun-cotton 
even under most severe conditions of exposure to heat, and that the material may be 
preserved for indefinite periods either in a moist state or completely immersed in water, 
without the slightest change, either chemical or physical, even if the damp or wet gun- 
cotton be continually exposed to daylight. The correctness of those statements has 
been fully confirmed by the further and extensive experience of the last five years. Not 
only have the samples which formed the subject of my former experiments been pre- 
served and found unchanged upon recent examination, but several hundred pounds 
have been preserved in the damp state for the past seven years, and many thousand 
pounds in the form of compressed disks have been stored wet for more than two years. 
Not the slightest symptom of change has been observed in any single instance; and as 
the substance may thus be preserved in a perfectly uninflammable condition, this 
* Phil. Trans. 1867, vol. clvii. p. 233. 
