Formulas for the making of Brass will be found under Alloys.

Colors For Polished Brass

The brass objects are put into boiling solutions composed of different salts, and the intensity of the shade obtained is dependent upon the duration of the immersion. With a solution composed of

Sulphate of copper. .. 120 grains

Hydrochlorate of ammonia ............ 30 grains

Water.............. 1 quart

greenish shades are obtained. With the following solution all the shades of brown from orange brown to cinnamon are obtained:

Chlorate of potash. .. 150 grains Sulphate of copper. .. 150 grains

Water.............. 1 quart

The following solution gives the brass first a rosy tint and then colors it violet and blue:

Sulphate of copper. . . 435 grains Hyposulphite of soda 300 grains

Cream of tartar...... 150 grains

Water.............. 1 pint

Upon adding to the last solution Ammoniacal sulphate of iron............ 300 grains

Hyposulphite of soda 300 grains there are obtained, according to the duration of the immersion, yellowish, orange, rosy, then bluish shades. Upon polarizing the ebullition the blue tint gives way to yellow, and finally to a pretty gray. Silver, under the same circumstances, becomes very beautifully colored. After a long ebullition in the following solution we obtain a yellow-brown shade, and then a remarkable fire red:

Chlorate of potash... 75 grains Carbonate of nickel. . 30 grains

Salt of nickel........ 75 grains

Water.............. 16 ounces

The following solution gives a beautiful, dark-brown color:

Chlorate of potash . . 75 grains

Salt of nickel....... 150 grains

Water............. 10 ounces

The following gives, in the first place, a red, which passes to blue, then to pale lilac, and finally to white:

Orpiment.......... 75 grains

Crystallized sal sodæ 150 grains

Water............. 10 ounces

The following gives a yellow brown:

Salt of nickel....... 75 grains

Sulphate of copper. . 75 grains Chlorate of potash .. 75 grains

Water............. 10 ounces

On mixing the following solutions, sulphur separates and the brass becomes covered with iridescent crystallizations:

I

Cream of tartar..... 75 grains

Sulphate of copper. . 75 grains

Water............. 10 ounces

II

Hyposulphite of soda 225 grains

Water............. 5 ounces

Upon leaving the brass objects immersed in the following mixture contained in corked vessels they at length acquire a very beautiful blue color: Hepar of sulphur .... 15 grains

Ammonia........... 75 grains

Water.............. 4 ounces