[PART IV.]
MILITARY PYROTECHNY.
[CHAPTER I.]
OBSERVATIONS IN GENERAL.
Laboratory-works comprehend all the operations of the workshop, connected with this branch of pyrotechny. The tools and instruments required for the laboratory, as well as the substances employed in the different preparations, we have already described.
Having noticed the origin of gunpowder, in the first part of our work, the following remarks in relation to that subject, namely, the history, of cannon, may be interesting.
For some time after the invention of artillery, gunpowder was of a weaker composition than that at present used, or than that described by Marcus Græcus. The first pieces of artillery were rough and very inconvenient, being usually framed of several pieces of iron bars, fitted together lengthwise, and hooped with rings. These guns were first employed in throwing stone shot of a prodigious weight, in imitation of the ancient machines, to which they succeeded, and were of an enormous bore. When Constantinople was besieged by Mahomet II. in the year 1453, the walls were battered with stone bullets, and some of the pieces were of 1200 lbs. caliber; but they could not be fired more than four times in twenty-four hours, and sometimes were burst by the first charge.
As mathematical knowledge increased in Europe, that of mechanics gradually advanced, and enabled artists, by making brass cannon of a much smaller bore for iron bullets, and capable of bearing a much greater charge of strong powder in proportion to their calibers, to produce a very material and important change in the construction and fabric of those original pieces. Guicciardin (History, &c. 1st book) informs us, that, about 114 years after the first use made of those unwieldy pieces by the Venetians, in their war against the Genoese in 1380, the French were able to procure, for the invasion of Italy, a great number of brass cannon, mounted on carriages, drawn by horses. He then enumerates the advantages which these pieces possessed, and particularly that they could be pointed with incredible quickness and expedition, in comparison with those formerly made use of in Italy. But, as our limits will not permit us to notice all the circumstances in connection with these pieces, it is sufficient to remark, that this change in the formation of artillery has as yet undergone no material alteration; if we except the introduction of carronades, first suggested by general Melville, and of Columbiads, by the late Mr. Barlow.