The pleasing green or golden color generally to be found on the cheap and light brass articles of French manufacture can be easily produced at but trifling expense by the following means: 1 3/4 ounces of caustic soda and 1 1/2 ounces of milk sugar are dissolved in 1 3/4 pints of water and boiled for a quarter of an hour. The solution is as clear as water at first, but gradually acquires a dark yellow color. The vessel is next taken from the fire, placed on a wooden support, and 1 1/2 ounces of a cold concentrated solution of blue vitriol stirred in. A red precipitate of suboxide of copper is at once formed, and by the time the mixture cools to 167° Fahrenheit the precipitate will have settled. A suitable wooden sieve is placed in the vessel, and in this the polished articles are laid. In about a minute the sieve is lifted up to see how far the operation has gone, and at the end of the second minute the golden color is dark enough. The sieve and articles are now taken out, and the latter are washed and then dried in sawdust. If the brass is left longer in the copper solution, in a short time a fine green lustre is produced, becoming yellow at first and then bluish green. After, it turns green, then the well-known iridescent colors finally appear.

To obtain uniform colors it is necessary that they be produced slowly, at tempei-atures between 135° and 170° Fahrenheit. The copper bath can be used repeatedly, and can be kept a long time, if bottled up tightly, without change. After it is exhausted it can be renewed by adding 3/8 of an ounce of caustic soda, replacing the water that has evaporated, heating to boiling, and adding 7/8 of an ounce of a cold solution of blue vitriol.