The Manufacturer and Builder 6, 1876
It is simply a solution of alum in diluted muriatic acid, which is used by steeping in it for a few seconds brass chains and other articles, so as to give them a golden color. If the articles are old and dirty-looking, it is better to use a mixture of 1 ounce sulphuric acid, 3/4 ounce nitric acid, 30 grains nitrate of potassa, and 1 ounce water; let the solution stand for a few hours. Dip the articles rapidly, wash at once in rain-water, and dry in sawdust. If the brass is very dirty, add a little bichromate of potash to the above solution, and after each dipping wash well with water, rub dry, and polish with rottenstone; then to give a better golden color which will not change so soon, the first-named solution may be used, or the lacquer mentioned in reply to query 1562.
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