This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1878 edition. Excerpt: ... Gum- Water and Ox-gall. Gum Arabic, in solution, will be necessary for use in improving the deep shadows of draperies, giving brilliancy to the hair, eyes, for ' touches, " and other purposes. Although a variety of things have been used for this end, gum Arabic is the best adapted for general use with water colors. It does not degrade the more delicate pigments, and yet bears out the more positive colors well. The strongest gum-water ever necessary may consist of one part gum and three parts of pure water, though it will more frequently be used much weaker. Gum should not be mixed with water containing any mineral properties. Do not attempt the use of it after it has become sour, or fermented; as it has not only lost its quality, but its use will unnecessarily imperil the success of the work. The solution may be preserved for use by adding a little Alcohol diluted fully one half with water; or by the addition of a small portion of the carbonate of ammonia; one scruple of the powdered carbonate to one ounce of the gum, reduced by maceration in two or three ounces of cold water. As will be learned hereafter, the gum-solution is not to be applied until the coloring is entirely finished; and then sparingly, as an excess of it is not only likely to crack, but it gives a vulgar effect. The making of photographs on Albumenized paper has become so universal that, unless special directions are given (or it is previously understood that the picture is to be painted) they are never made upon what is designated "plain" (or not albumenized) paper. Hence, if the photograph in hand be one of the former description, it will be found that the water-color will neither sink into, nor even flow upon, the albumenized surface. To remedy this difficulty, ...