report prepared this year (1909) by Allerton S. Cushman, of the Office of Public Roads, United States Department of Agriculture.

flake, etc. Any of these kinds is to a limited extent eligible for paint-making, but the amorphous 80-90 per cent. carbon is generally conceded the best on account of its susceptibility to finer division. Much of the stuff sold as graphite is but a carbonaceous schist—that is, a kind of coal or slate. Genuine amorphous or crystalline graphites do not make good paints; they are soft, unctuous, and greasy, and serve better as lubricators, but if compounded with a pigment or pigments that have affinity for oil, like red lead, white lead, zinc oxide, etc., good results may be obtained from their use as an important component of paint.

Electric graphite is now in use at times as a carbon pigment. It is made by heating anthracite coal to a very high temperature (as  high  as  6,000°  F.) in an electric fur-