The foregoing recipes are for copper and brass where so stated and the following are for brass only:
No. 1. To obtain a dark antique finish on brass apply butter of antimony to the brass and allow it to dry.
No. 2. A steel blue color can be produced on brass by immersing in the following solution : sodium hyposulphite, 4 ounces; acetate of lead, 2 ounces; water, 2 quarts. This solution is used hot. Various colors can be obtained by varying the degree of heat and the time of immersion.
No. 3. To dull brass apply with a brush the following solution: 12 parts hydrochloric acid, 1 part ferric oxide. Apply with a brush.
No. 4. A slightly different result may be obtained by adding to the above recipe one part of white arsenic.
No. 5. A solution for coloring brass steel gray: dissolve 4 ounces of muriate of arsenic in 2 quarts of water and immerse the articles.
No. 6. The so-called Flemish gray on brass is obtained by dipping in the following solution: muriatic acid, 1/2 ounce; white arsenic, 1/4 ounce; potassium sulphuret, 6 grains; water, 2 gallons. Mix the arsenic in the acid, add the water, then the potassium.
No. 7. Brown to red shades for brass: dissolve 8 ounces nitrate of iron and 8 ounces of hyposulphite of soda in 2 quarts of water.
No. 8. Black to brown shades for brass: dissolve 3 ounces nitrate of iron and 2 ounces perchloride of iron in 3 quarts of water.
No. 9. For a golden bronze color on brass: dissolve 3 pounds nitrate of potash in 2 quarts of sulphuric acid, then add 2 gills of. nitric acid and 2 gills of hydrochloric acid.
No. 10. For a bright green: dissolve 1/2 pound sal ammoniac and 1/2 pound sulphate of copper in 2 quarts of boiling water. Apply with a stiff brush and allow to dry.
No. 11. A duller green can be produced by dissolving 4 ounces sulphate of copper in 2 quarts of boiling water. Immerse the articles and allow them to dry.
No. 12. Still another method is to immerse the articles in a hot solution consisting of hyposulphite of soda, 4 ounces; nickel salts. 4 ounces; water, 2 quarts. After immersion in the solution dip the articles in clean boiling water.
No. 13. There is one very interesting method of coloring brass that has no distinctive name, and that is to copper plate the brass and then to polish off the copper plate on the high spots leaving the copper plate in the background, and then to lacquer the work. This makes a very effective finish and is one that is not commonly known. The method is as follows: mix together 1/2 pint sulphuric acid and 2 pints of water; add 1 tablespoonful sulphate of copper crystals. After the piece of brass work has been thoroly cleaned, wind around it a piece of thin iron wire or a narrow strip of sheet iron, and place in the solution for about 15 minutes. This will copper plate the article. Dry with a cloth, polish all in one direction with a piece of smooth emery cloth, and lacquer and wax. If the solution gets worn out put in more sulphate of copper. There is an interesting chemical fact in connection with this kind of copper plating, and that is that the sulphate of copper is simply copper in another form, suspended in the solution, but the iron displaces or precipitates it and deposits it on the copper, or upon any piece of iron that is held in the solution. This is a practical application of the "electromotive series" of chemistry.