To dye feathers black, soak them in nitrate of iron liquor at 70 B. for twelve hours, moving them well about; remove and wash, then boil in a decoction of 21b. of logwood and lib. of quercitron or sumach in 1 gal. of water; remove, wash, dip in an emulsion made by shaking a solution of pearlash in water (1 oz. to a pint) with an equal measure of olive oil, and then swing the feathers about in a warm room, or pin them to a line to dry.