Chapter 30 - Page 2

he had
at his disposal saltpeter, sulphur, and coal; but this preparation requires
extreme care, and without special tools it is difficult to produce it of a
good quality. Harding preferred, therefore, to manufacture pyroxyle, that
is to say gun-cotton, a substance in which cotton is not indispensable, as
the elementary tissue of vegetables may be used, and this is found in an
almost pure state, not only in cotton, but in the textile fiber of hemp and
flax, in paper, the pith of the elder, etc. Now, the elder abounded in the
island towards the mouth of Red Creek, and the colonists had already made
coffee of the berries of these shrubs, which belong to the family of the
caprifoliaceae.

The only thing to be collected, therefore, was elder-pith, for as to the
other substance necessary for the manufacture of pyroxyle, it was only
fuming azotic acid. Now, Harding having sulphuric acid at his disposal, had
already been easily able to produce azotic acid by attacking the saltpeter
with which nature supplied him. He accordingly resolved to manufacture and
employ pyroxyle, although it has some inconveniences, that is to say, a
great inequality of effect, an excessive inflammability, since it takes
fire at one hundred and seventy degrees instead of two hundred and forty,
and lastly, an instantaneous deflagration which might damage the firearms.
On the other hand, the advantages of pyroxyle consist in this, that it is
not injured by damp, that it does not make the gun-barrels dirty, and that
its force is four times that of ordinary powder.

To make pyroxyle, the cotton must be immersed in the fuming azotic acid
for a quarter of an hour, then washed in cold water and dried. Nothing
could be more simple.

Cyrus Harding had only at his disposal the ordinary azotic acid and not
the fuming or monohydrate azotic acid, that is to say, acid which emits
white vapors when it comes in contact with damp air; but by substituting
for the latter ordinary azotic acid, mixed, in the proportion of from three
to five volumes of concentrated sulphuric acid, the engineer obtained the
same result. The sportsmen of the island therefore soon had a perfectly
prepared substance, which, employed discreetly, produced admirable results.

About this time the settlers cleared three acres of the plateau, and the
rest was preserved in a wild state, for the benefit of the onagers. Several
excursions were made into the Jacamar Wood and the forests of the Far West,
and they brought back from thence a large collection of wild vegetables,
spinach, cress, radishes, and turnips, which careful culture would soon
improve, and which would temper the regimen on which the settlers had till
then subsisted. Supplies of wood and coal were also carted. Each