154 EXPERIMENTS WITH GUN-COTTON. 



the powder, the former exploded so instantaneously as to 

 leave the gunpowder unexploded. The gun-cotton explodes 

 at about 400 of Fahrenheit ; with a vividness of flame 

 which is perfectly dazzling leaving scarcely any residue 

 behind. It has been stated that no smoke is emitted : 

 this is erroneous. A slight smoke, or rather vapour, is 

 thrown off; but it disappears so soon as to occasion no 

 inconvenience. After repeated explosions of the cotton, 

 the room in which the experiments were conducted was 

 perfectly clear. 



" It is difficult to over-estimate the advantages attendant 

 upon the use of the gun-cotton in mines ; since the smoke 

 proceeding from the coarse gunpowder used for blasting 

 purposes occasions so much annoyance and injury to the 

 health of the miners. The experiments in blasting tried in 

 the Cornwall mines a short time ago, were most satisfactory 

 and conclusive in favour of the gun-cotton. Another of 

 its strange qualities consists in its not being deteriorated 

 by damp or wet. Some gun-cotton which had been 

 steeped in water for sixty hours, and dried by exposure to 

 the air, exploded with the same facility, and as instan- 

 taneously, as cotton which had not been wetted. Professor 

 Schonbein stated that immersion in water for two months 

 has not impaired its explosive qualities in the slightest 

 degree. 



" The experiments with fowling-pieces and rifles were 

 highly interesting and satisfactory. A gun charged with 

 thirty grains of prepared cotton propelled an equal charge 

 of shot with greater force and precision, at a distance of 

 forty yards, than was done by the same gun loaded with a 

 hundred and twenty grains of gunpowder. A rifle charged 



