For Lights of another Sort.
Saltpetre three pound, brimstone one pound, meal powder one pound, antimony ten ounces and a half. All these ingredients must be mixed with the oil of spike.
For a Red Fire.
Meal powder three pound, charcoal twelve ounces, and saw dust eight ounces.
For a Common Fire.
Saltpetre three pound, charcoal ten ounces, and brimstone two ounces.
To make an Artificial Earthquake.
Mix the following ingredients to a paste with water, and then bury it in the ground, and in a few hours the earth will break and open in several places. The composition: Sulphur four pound, and steel dust four pound.
Having laid down, under the preceding heads, the different compositions used in fireworks by our modern artists; I shall, in the next place, give some tables of charges that were formerly used, according to the several accounts given by those authors from whom they are collected: but if the reader will consider, he will find the charges in these tables to be very uncertain, by comparing their method of determining the size and weight of rockets, and the proportions of ingredients thereto, with the method taught in this work, which is so plain, easy, and certain, that I have never yet known it fail; and doubt not, but that it will be so allowed by all who chuse to make a tryal thereof.
The subsequent table is taken from Siemienowicz, wherein is specified the different charges of sky rockets, from half an ounce to one hundred pound; the charges being calculated in proportion to the weight of a leaden ball of the same diameter as the bore of each mould; which bores are divided into inches and lines[1], and each line into twelve equal parts, according to the French method.