both as picric acid and in the form of picrates. Another nitro body that
is used as an explosive is nitro-naphthalene, C_{10}H_{6}(NO_{2})_{2}, in
roburite, securite, and other explosives of this class. The hexa-nitro-
mannite, C_{6}H_{8}(ONO_{2})_{6}, is formed

[Illustration: No. 1]

[Illustration: META-DINITRO-BENZENE No.2]

by treating a substance known as mannite, C_{6}H_{8}(OH)_{6}, an alcohol
formed by the lactic acid fermentation of sugar and closely related to the
sugars, with nitric and sulphuric acids. It is a solid substance, and very
explosive; it contains 18.58 per cent. of nitrogen.

Nitro-starch has also been used for the manufacture of an explosive.
Muhlhauer has described (_Ding. Poly. Jour._, 73, 137-143) three nitric
ethers of starch, the tetra-nitro-starch, C_{12}H_{16}O_{6}(ONO_{2})_{4},
the penta- and hexa-nitro-starch. They are formed by acting upon potato
starch dried at 100° C. with a mixture of nitric and sulphuric acids at a
temperature of 20° to 25° C. Rice starch has also been used in its
production. Muhlhauer proposes to use this body as a smokeless powder, and
to nitrate it with the spent mixed acids from the manufacture of nitro-
glycerine. This substance contains from 10.96 to 11.09 per cent. of
nitrogen. It is a white substance, very stable and soluble even in cold
nitro-glycerine.

The explosive bodies formed by the nitration of jute have been studied by
Messrs Cross and Bevan. and also by Mühlhäuer. The former chemists give
jute the formula C_{12}H_{18}O_{9}, and believe that its conversion into a
nitro-compound takes place according to the equation--