All sorts of skins— sheepskins, goatskins, coltskins, and light calfskins—are adapted for the preparation of bronze leather. In this preparation the advantage lies not only in the use of the faultless skins, but scarified skins and those of inferior quality may also be employed. The dressing of the previously tanned skin must be carried out with the greatest care, to prevent the appearance of spots and other faults. After tanning, the pelts are well washed, scraped, and dried. Then they are bleached. For coloring, it is customary to employ methyl violet which has previously been dissolved in hot water, taking 100 parts, by weight, of the aniline color to 8,000 parts, by weight, of water. If in the leather-dressing establishment a line of steam piping be convenient, it is advisable to boil up all the coloring dyes, rather than simply to dissolve them; for in this way complete solution is effected. Where steam is used no special appliance is required for boiling up the dyes, for this may take place without inconvenience in the separate dye vats. A length of steam hose and a brass nozzle with a valve is all that is needed. It may be as well to add here that the violet color for dyeing may be made cheaper than as above described. To 3,000 parts, by weight, of pretty strong logwood decoction add 50 parts, by weight, of alum and 100 parts, by weight, of methyl violet. This compound is almost as strong as the pure violet solution, and instead of 8,000 parts, by weight, we now have 30,000 parts, by weight, of color".

The color is applied and well worked in with a stiff brush, and the skins allowed to stand for a short time, sufficient to allow the dye to penetrate the pores, when it is fulled. As for the shade of the bronze, it may be made reddish, bluish, or brownish, according to taste.

For a reddish or brownish ground the skins are simply fulled in warm water, planished, fulled again, and then dyed. According to the color desired, the skins are treated with cotton blue and methyl violet R, whereupon the application of the bronze follows.

The bronze is dissolved in alcohol, and it is usual to take 200 parts, by weight, of bronze to 1,000 of alcohol. By means of this mixture the peculiar component parts of the bronze are dissolved. For a fundamental or thorough solution a fortnight is required. All bronze mixtures are to be well shaken or agitated before using. Skins may be bronzed, however, without the use of the bronze colors, for it is well known that all the aniline dyes present a bronze appearance when highly concentrated, and this is particularly the case with the violet and red dyes. If, therefore, the violet be applied in very strong solutions, the effect will be much the same as when the regular bronze color is employed.

Bronze color on a brown ground is the most beautiful of all, and is used to the greatest advantage when it is desirable to cover up defects. Instead of warm clear water in such a case, use a decoction of logwood to which a small quantity of alum has been added, and thus, during the fulling, impart to the skins a proper basic tint, which may, by the application of a little violet or bronze color, be converted into a most brilliant bronze. By no means is it to be forgotten that too much coloring matter will never produce the desired results, for here, as with the other colors, too much will bring out a greenish tint, nor will the gloss turn out so beautiful and clear. Next rinse the skins well in clean water, and air them, after which they may be dried with artificial heat. Ordinary as well as damaged skins which are not suitable for chevreaux (kid) and which it is desirable to provide with a very high polish, in order the more readily to conceal the defects in the grain, and other imperfections, are, after the drying, coated with a mixture, compounded according to the following simple formula: Stir well 1 pint of ox blood and 1 pint of unboiled milk in 10 quarts of water, and with a soft sponge apply this to the surface of the skin. The blood has no damaging effect upon the color. Skins thus moistened must not be laid one upon another, but must be placed separately in a thoroughly well-warmed chamber to dry. When dry they are glossed, and may then be pressed into shagreen or pebbled. The thin light goatskins are worked into kid or chevreaux. Properly speaking, they are only imitation chevreaux (kid), for although they are truly goatskins, under the term chevreaux one understands only such skins as have been cured in alum and treated with albumen and flour.

After drying, these skins are drawn over the perching stick with the round knife, then glossed, stretched, glossed again, and finally vigorously brushed upon the flesh side with a stiff brush. The brushing should be done preferably by hand, for the brushing machines commonly pull the skins out of all shape. Brushing is intended only to give the flesh side more of a flaky appearance.

During the second glossing care must be taken that the pressure is light, for the object is merely to bring the skin back into its proper shape, lost in the stretching; the glossing proper should have been accomplished during the first operation.