Page:History of the Royal Society.djvu/303



materials of Gun-powder are Salt-peter, Brimstone, and Coal; the Peter and Brimstone must be both refined if you mean to make good Powder, and the Coal must be Withy and Alder equal parts; for Withy alone is counted too soft, and some do commend Hazle alone to be as good as the other two.

'The whole Secret of the Art consists in the proportion of the Materials, the exact mixture of them, that in every the least part of Powder may be found all the Materials in their just proportion; then the Corning or making of it into Grains; and lastly the Drying and Dusting of it.

'The proportion is very differently set down by several Authors; Baptista Porta tells us the ordinary Powder is made of four Parts of Peter, one of Sulphur, and one of Withy Coal: But the best Powder of 6, or 8 of Peter, and one a piece of the other, which agrees pretty well with Bonfadini a late Italian Writer, in his Book of the Art of Shooting flying, where, to make the best Gun powder, he prescribes seven Parts of Peter, one of Brimstone, and of Hazel Coal an ounce less in every pound: Cardan says; Constat ex tribus Halinitri partibus, duabus Rh