166.  To soften horn

To 1 lb. of wood ashes, add 2 lbs. of quicklime; put them into a quart of water, let the whole boil till reduced to one third, then dip a feather in, and if, on drawing it out, the plume should come off, it is a proof that it is boiled enough, if not, let it boil a little longer; when it is settled filter it off, and in the liquor thus strained put in shavings of horn; let them soak for three days, and, first anointing your hands with oil, work the horn into a mass, and print or mould it into any shape you please.

167.  To make moulds of horn

If you wish to take the impression of any coin, medal, &c., previously anoint it with oil, then lay the horn shavings over it in its softened state; when dry the impression will be sunk into the horn, and this will serve as a mould to reproduce, either by plaster of Paris, putty and glue, or isinglass and ground egg shells, the exact resemblance of the coin or medal.

168.  To case figures in imitation of ivory

Make isinglass and strong brandy into a paste, with powder of egg shells, very finely ground; you may give it what colour you please, but cast it warm into your mould, which you previously oil over; leave the figure in the mould till dry, and you will find, on taking it out, that it bears a very strong resemblance to ivory.

169.  True gold powder

Put some gold leaf, with a little honey or thick gum water, (whenever I speak of gum I mean gum arabic,) into an earthen mortar, and pound the mixture till the gold is reduced to very small particles; then wash out the honey or gum repeatedly with warm water, and the gold will be left behind in a state of powder, which, when dried, is fit for use.

170.  True gold powder

Another, and perhaps better method of preparing gold powder is to heat a prepared amalgam of gold in a clean open crucible, (an amalgam of any metal is formed by a mixture of quicksilver with that metal) continuing a very strong heat till all the mercury has evaporated, stirring the amalgam all the while with a glass rod; when the mercury has entirely left the gold, grind the remainder in a Wedgewood’s mortar, with a little water, and when dried it will be fit for use.  The subliming the mercury is, however, a process injurious to the health.

171.  Colour heightening compositions

For yellow gold, dissolve in water 6 ozs. of saltpetre, 2 ozs. of copperas, 1 oz. of white vitriol, and 1 oz. of alum.  If wanted redder, add a small portion of blue vitriol.

172.  For green gold

Dissolve in water a mixture consisting of 1-1/2 oz. of saltpetre; vitriol and sal-ammoniac, 1-1/4 oz. of each, and 1 oz. verdigris.

173.  For red gold