results of his investigation are here given.

The explosive properties of the substance indicated a probable
nitro-compound of one of the solder metals (tin and lead), and as the
lead salts are more stable and better understood than those of tin, it
was resolved to investigate the latter, in hope of obtaining a similar
explosive compound. Experiments on the action of moist potassium nitrate
on pure tin led to no result, as no explosive body was formed. Stannous
nitrate, Sn(NO_{3})_{2}, formed by the action of dilute nitric acid on
tin, has long been known, but only in solution, as it is decomposed on
evaporating. By adding freshly precipitated moist brown stannous oxide
to cool nitric acid of sp. gr. 1.20, as long as solution occurred, and
then cooling the solution to -20°, Weber obtained an abundance of
crystals of the composition Sn(NO_{3})_{2} + 20H_{2}O. They resemble
crystals of potassium chlorate. They cannot be kept, as they liquefy at
ordinary temperatures. An insoluble _basic_ salt was obtained by
digesting an excess of moist stannous oxide in solution of stannous
nitrate, or by adding to a solution of stannous nitrate by degrees, with
constant stirring, a quantity of sodium carbonate solution insufficient
for complete precipitation. Thus obtained, the basic salt, which has the
composition Sn_{2}N_{2}O_{7}, is a snow-white crystalline powder, which
is partially decomposed by water, and slowly oxidized by long exposure
to the air, or by heating to 100°. By rapid heating to a higher
temperature, as well as by percussion and friction, it explodes
violently, giving off a shower of sparks. This compound is also formed
when a fine spray of nitric acid (sp. gr. 1.20) is thrown upon a surface
of tin or solder. It is also formed when tin or solder is exposed to the
action of a solution of copper nitrate, and thus formed presents the
properties already described.