The Chemistry of Powder and Explosives - Sciencemadness Dot Org

358 DYNAMITE AND OTHER HIGH EXPLOSIVES
breakfast. Lefort and Mile, de Chevraud were the first to return.
The material exploded, throwing them to a considerable distance
and causing such injuries that they both died within a few
minutes. In 1849 the problem of chlorate gunpowder was again
attacked by Augendre vho invented a white powder made from
potassium chlorate 4 parts, cane sugar 1 part, and potassium
ferrocyanide 1 part. However, no satisfactory propellent powder
for use in guns has yet been made from chlorate. Chlorate
powders are used in toy salutes, maroons, etc., where a sharp
explosion accompanied by noise is desired, and chlorate is used
in primer compositions and in practical high explosives of the
Sprengel type (described above) and in the Cheddites and Silesia
explosives.
Many chlorate mixtures, particularly those which contain sulfur,
sulfides, and picric acid, are extremely sensitive to blows and
to friction. In the Street explosives, later called Cheddites because
they were manufactured at Chedde in France, the chlorate
is phlegmatized by means of castor oil, a substance which appears
to have remarkable powers in this respect. The French Commission
des Substances Explosives in 1897 commenced its first investigation
of these explosives by a study of those which are
listed below, and concluded 35 that their sensitivity to shock is
I II III
Potassium chlorate 75.0 74.6 80.0
Picronitronaphthalene 20.0
Nitronaphthalene 5.5 12.0
Starch 14.9
Castor oil 5.0 5.0 8.0
less than that of No. 1 dynamite (75% guhr dynamite) and that
when exploded by a fulminate cap they show a considerable
brisance which however is less than that of dynamite. Later
studies showed that the Cheddites had slightly more force than
No. 1 dynamite, although they were markedly less brisant because
of their lower velocity of detonation. After further experimentation
four Cheddites were approved for manufacture in
France, but the output of the Poudrerie de Vonges where they
were made consisted principally of Cheddites No, 1 and No. 4.
Mem. Poudres, 9, 144 (1897-1898); 11, 22 (1901); 12, 117, 122 (190S-
1904); 13, 144, 282 (1905-1906); IS, 135 (1909-1910); 16, 66 (1911-1912).