Take 4 ounces of the best magistery of bismuth,
2 ounces of fine starch powder.
Mix them well together, and put them into a subsiding glass, wide
at top and narrow at bottom; pour over them a pint and a half of
proof spirit, and shake them well; let them remain a day or two.
When the powder falls to the bottom, pour off the spirit, leaving
it dry; then place the glass in the sun, to evaporate the moisture.
Next turn out the white mass, the dirty parts of which form the
top, whilst the pure ingredients remain at the bottom. If there
be any dirty particles, scrape them off, and again pulverize the
remaining part of the cake, and pour more proof spirit over it.
Proceed as before; and, if there be any moisture remaining, place
the cone on a large piece of smooth chalk, to absorb its moisture.
Cover the whole with a bell-glass, to preserve it from dust, and
set it in the sun to dry and whiten it. Next grind the mass with a
muller on a marble stone, and keep the powder in a glass bottle,
secured, by a ground stopper, from air.