The Chemistry of Powder and Explosives - Sciencemadness Dot Org

EARLY HISTORY OF NITRATED CARBOHYDRATES 245
soon cooperated with each other to exploit its use in artillery.
Pelouze had nitrated paper at an earlier time, and the question
may indeed be raised whether he was not the first discoverer of
nitrocellulose. Before that, Braconnot, professor of chemistry at
Nancy, had prepared a nitric ester from starch. The principal
events in the early history of these substances are summarized
below. 77
1833. Braconnot 78 found that starch dissolved in concentrated
nitric acid and that the liquid on dilution with water gave
a curdy precipitate of material which, after washing, dried out
to a white, pulverulent, tasteless, and neutral mass. The product
gave a brown color with a solution of iodine, It was not affected
by bromine. It did not dissolve in boiling water but softened to
a sticky mass. Dilute sulfuric acid did not affect it. Concentrated
sulfuric acid dissolved it, and the solution gave no precipitate if
it was diluted with water. The material, to which Braconnot
gave the name of xylo'idine, dissolved in acetic acid very readily
on heating, and the solution, if evaporated slowly, gave a transparent
film which retained its transparency when placed in water.
Applied to paper or cloth it yielded a brilliant, varnish-like
coating which was impervious to water. Xylo'idine took fire very
readily. It carbonized and liquefied if heated upon a piece of
cardboard or heavy paper while the cardboard or paper, though
exposed directly to the heat, was not appreciably damaged. Sawdust,
cotton, and linen yielded products which Braconnot considered
to be identical with the xylo'idine from starch.
1838. Pelouze 79 studied xylo'idine further. He found that if
starch was dissolved in concentrated nitric acid and if the solution
was diluted immediately with water, xyloidine precipitated
and the acid filtrate on evaporation yielded practically no residue.
If the solution of starch in nitric acid was allowed to stand before
being precipitated with water, then the amount of xyloidine was
less. If it was allowed to stand for 2 days, or perhaps only for
some hours, the xyloidine was entirely destroyed, a new acid was
formed, no precipitate appeared when the solution was diluted,
77 The papers which are cited in this connection have been published in
English in the book by George W. MacDonald, "Historical Papers on
Modern Explosives," Whittaker & Co., London and New York, 1912.
78 Ann. chim. phys., [2] 52, 290 (1833).
Compt. rend., 7, 713 (1838).