SUBSTITUTES EOll GUNPOIVDER. 
G9 
which experience has proved to he essential to safety, and which, in spite of the strictest 
supervision, are unquestionably sometimes overlooked or imperfectly carried out by 
workmen. Explosions of gunpowder, generally of a serious character, do occur, how¬ 
ever, though very rarely, during the transport of the material, or in the magazines 
where it is stored. The great explosion of a gunpowder magazine at Erith in Septem¬ 
ber, 1864, specially directed the attention of Government and the public generally to the 
necessity of adopting measures for reducing, as much as possible, the risk of occur¬ 
rence of such disastrous accidents. Hence, much interest has recently been excited by 
a well-known method of rendering gunpowder less dangerous in its character, which has 
been brought prominently before the public by Mr. Gale, and which consists of diluting 
powder, or separating its grains from each other, by means of a finely-powdered 
non-explosive substance. Attempts have several times been made in past years to apply 
to practical purposes the obvious fact, of which nobody acquainted with the nature 
of gunpowder could be ignorant, that, by interposing between the grains of powder a 
sufficient quantity of a finely-divided material, which offers great resistance to the 
transmission of heat, the ignition of separate grains of the entire mass may be accom¬ 
plished without risk of inflaming contiguous grains. In 1835, Piobert made a series of 
experiments with the view to apply this fact practically, to reduce the explosiveness of 
gunpowder, and similar experiments of an extensive character were carried on by a 
Kussian chemist, Fadeiff, between 1841 and 1844. These experimenters found that the 
object in view might be attained by diluting gunpowder with any one of its compo¬ 
nents ; they also employed very fine sand (a substance closely allied in its physical cha¬ 
racters to the powdered glass, which Mr. Gale now proposes to use) ; but the preference 
appears to have been given to a particular form of carbon. It was not attempted alto¬ 
gether to prevent the burning of a mass of gunpowder, when a spark or flame reached 
any portion, but to reduce the rapidity of combustion so greatly as to prevent the occur¬ 
rence of a violent explosion. No more than this is accomplished by the employment of 
powdered glass in the proportions directed by Mr. Gale. Indeed, as the quantity of di¬ 
luent required to give to different kinds of gunpowder the character of equally slow- 
burning materials increases with the explosiveness of the particular powder and with 
the size of its grain, the proportion of powdered glass with which the gunpowder em¬ 
ployed in rifled cannon would have to be mixed to render it only slow-burning, would 
be about double the quantity required for almost altogether preventing the ignition of 
fine-grain powder, or of the comparatively weak blasting powder wfith which Mr. Gale’s 
public experiments appear generally to have been instituted. Although a sufficient 
dilution of gunpowder may secure such comparative safety to the neighbourhoods of 
large magazines, or to the crews of merchant vessels in which gunpowder (for blasting 
purposes, etc.) is transported, as to compensate fully for the inconvenience attending 
the great increase of volume of the powder, there is no doubt that such a treatment of 
gunpowder actually issued for military and naval service would be attended by more 
than one serious obstacle ; such as, the tendency of the powder, unless very largely di¬ 
luted, to separate from the glass, during transport by land or sea, to so considerable 
an extent as very greatly to diminish the degree of security originally aimed at; the 
very great addition which would have to be made to the arrangements for carrying the 
necessary ammunition, in active service; the necessity for introducing, in the field or 
on board ship, the operations of separating the powder from the glass and transferring it 
to cartridges and shells (which, whatever sifting and other arrangements w'ere adopted, 
would be time-taking and very dangerous), instead of preserving the ammunition ready 
for immediate use; and, above all, the incalculable mischief which would inevitably re¬ 
sult from the establishment, in the minds of the soldier and sailor, of an erroneous feel¬ 
ing of security in dealing with gunpowder, which, however harmless it may for a time 
be rendered, must finally be handled by the men in its explosive form. The extremely 
rare occurrence of accidents with gunpowder, on board ship or in active land-service, is 
mainly due to the strictest enforcement of precautionary regulations, some of which 
may appear at first sight exaggerated or almost absurd, but which combine to main¬ 
tain a consciousness of danger and a consequent vigilance indispensable to safety. 
One of the most remarkable materials recently employed to replace gunpowder as a 
destructive agent, is nitro-glycerine. This substance was discovered by Sobrero, in 
1847, and is produced by adding glycerine in successive small quantities to a mixture of 
one volume of nitric acid of sp. gr. 1-43, and two volumes of sulphuric acid of sp. gr. 
