Scientific American 32, 1.5.1847
Take any quantity of nitro muriate of gold, and evaporate by exposing it to a gentle heat in a glass tumbler or phial; the gold will form itself in crystals on the bottom and sides of the vessel; collect these crystals and dissolve them in ten times their weight of pure water. Then put a gill of water into a common flask and add one ounce of graduated zinc, and one fourth of an ounce of sulphuric acid. Hydrogen gas will be evolved, and rise through the neck of the flask, which must not be stopped. Immerse a piece of white silk in the above mentioned aqueous solution of gold, and expose it, while wet, to the current of gas as it rises from the flask; the gold will soon be revived and the silk will become beautifully and permanently gilt. Any letters or flowers may be drawn on the silk with a camel hair pencil dipped in the solution, and on being exposed to the action of the gas, will be revived and shine with metallic brilliancy. The silk must be kept moist with water till the gold is revived. Zinc may be prepared for the above purpose, by melting it and stirring it continually with a stick or iron rod while it is cooling; or it may be pulverized with a hammer as soon as it becomes solid.
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