Proposed Substitutes for Gunpowder. 85 
simply burns; and if placed upon paper or metal, and held 
over a source of heat, it explodes feebly after a short time, 
burning with a smoky flame. If paper moistened with it 
be simply struck, a somewhat violent detonation is pro- 
duced. Alfred Nobel, a Swedish engineer, was the first to 
attempt the application of nitro-glycerine as an explosive 
agent, in 1864. 
Some experiments were, in the first instance, made with 
gunpowder, the grains of whichhad been saturated with nitro- 
glycerine. This powder burnt much as usual, but with a 
brighter flame in open air. When confined in shells or 
blast holes, greater effects were, however, produced with it 
than with ordinary gunpowder; its destructive action is 
described as having been from three to six times ¢reater 
than that of powder. The liquid could not be employed as 
_a blasting agent, in the ordinary manner, as the application 
of flame to it from a common fuze would not cause it to 
explode. But Mr. Nobel has succeeded, by employing a 
special description of fuze, in applying the liquid alone as 
a very powerful destructive agent. The charge of nitro- 
glycerine having been introduced, in a suitable case, into 
the blast hole, a fuze, to the extremity of which is attached 
a small charge of gunpowder, is affixed immediately over 
the liquid. The concussion produced by the exploding 
powder, upon ignition of the fuze, effects the explosion of 
the nitro-glycerine. 
The destructive action of this material is estimated, by 
those who have made experiments in Sweden and 
Germany, as about that of an equal weight of gunpowder. 
Therefore, although its cost is about seven times that of 
blasting powder, its use is stated to be attended with great 
economy, more especially in hard rocks, a considerable 
saving being effected by its means in the labour of the 
miners, and in the time occupied in performing a given 
amount of work, as much fewer and smaller blast holes are 
required than when gunpowder is employed. The material 
appears to have recently received considerable application 
in some parts of Germany, and in Sweden; but, in Eng- 
land, its employment has been confined to one set of ex- 
periments instituted in Cornwall last summer, upon which 
occasion a wrought iron block, weighing about three 
hundred weight, was rent into fragments, by the explosion 
of a charge of less than one ounce of nitro-glycerine placed 
in a central cavity. 
Nitro-glycerine appears, therefore, to possess very im- 
NEW SERIES.—VOL, I. H 
