Carbon Black. (U. S. Geological Survey Press BuUetin, No. 48o.)--The demand for carbon black, which is produced from natural gas, has greatly iaacreased during recent years, but the supply of natural gas is rapidly decreasing, a fact Vh'at is viewed with no little alarm by the producers and consumers and that has brought about a general demand for information on the subject. Accordingly, in 1919 the Geological Survey began a canvass of the situation, and the result of this canvass is a report entitled " Carbon Black from Natural Gas in 192o," by E. G. Sievers.
Carbon black is a fluffy, velvety black pigment, frequently confused with lampblack, which is gray in color and which is produced from oil or other carbonaceous material. For many of its uses carbon black is superior to lampblack in quality, but for some uses, as for certain pigments in paints, lampblack is superior.
Carbon black !has been used as a pigment in printer's ink instead of lampblack since 1864. It is also used as a coloring and reinforcing material in the rubber industry and is extensively used in the pain~t trade.
About xo per cent. of the carbon black produced annually is used in the manufacture of stove and shoe polish, phonograph records, black leather, bookbinders' board, buttons, carbon and other black and gray papers, typewriter ribbons, carriage cloth, celluloid, electric insulators, cement colors, crayons, drawing and marking inks, artificial stone, black tile, and tarpaulins.
The exports now amount to 15 per cent. of the output, but before the war they amounted to 33 per cent. They will probably never again reach this amount, owing to the increased demand in the United States for carbon black.