Among the Dakota, colors for dyeing porcupine quills are obtained chiefly from plants, or have been until very recently. The vegetable colors, being soluble, penetrate the substance of the quills more evenly and beautifully than the mineral colors of eastern manufacture. The black color of some of the Pueblo pottery is obtained by a special burning with pulverized manure, into which the vessel is placed as it is cooling after the first baking. The coloring matter--soot produced by smoke--is absorbed into the pores of the vessel, and will not wear off as readily as when colors are applied to the surface with sticks or primitive brushes. In decorating skins or robes the Arikara Indians boil the tail of the beaver, thus obtaining a viscous fluid which is in reality thin glue. The figures are first drawn in outline with a piece of beef-rib, or some other flat bone, the edge only being used after having been dipped into the liquor. The various pigments to be employed in the drawing are then mixed with some of the same liquid, in separate vessels, when the various colors are applied to the objects by means of a sharpened piece of wood or bone. The colored mixture adheres firmly to the original tracing in glue, and does not readily rub off. When similar colors are to be applied to wood, the surface is frequently picked or slightly incised to receive the color more securely. For temporary purposes, as for mnemonic marks upon a shoulder blade of a buffalo or upon a piece of wood to direct comrades upon the course to be pursued to attain a certain object, a piece of red chalk, or a lump of red ocher of natural production is resorted to. This is often carried by the Indian for personal decoration. A small pouch, discovered on the Yellowstone River in 1873, which had been dropped by some fleeing hostile Sioux, contained several fragments of black micaceous iron. The latter had almost the appearance and consistence of graphite, so soft and black was the result upon rubbing it. It had evidently been used for decorating the face as warpaint. Mr. Dall, in treating of the remains found in the mammalian layers in the Amakuak cave, Unalashka, remarks (Contributions to N. A. Ethnology, I, p. 79) that “in the remains of a woman’s work-basket, found in the uppermost layer in the cave, were bits of this resin [from the bark of pine or spruce driftwood], evidently carefully treasured, with a little birch-bark case (the bark also derived from drift logs) containing pieces of soft hæmatite, graphite, and blue carbonate of copper, with which the ancient seamstress ornamented her handiwork.”