Petroleum

Rock-oil; Naphtha; probably a product of the dry distillation of coal-beds caused by the earth's heat; or of the dry distillation of the fatty constituents of fo il organisms. In a crude condition, it is a thick, oily liquid, of brownish color, with greenish luster. On exposure to air, its more volatile constituents are lost; it then thickens and pa es into asphaltum. P., American, consists almost exclusively of normal paraffins. In a crude form, it has a specific gravity of from 0.8 to 0.92, and distils over at from 3000 to 3600 C. and beyond this. P. Benzine, a product of petroleum obtained by fractional distillation; it has a specific gravity of from 0.68 to 0.72, and distils at from 700 to 900 C., and consists of hexane and heptane. P., Caucasian (from Baker), has a higher specific gravity than American petroleum; it contains le of the light volatile constituents and distils at about 1500 C. P. Ether, a product of petroleum obtained by fractional distillation; it has a specific gravity of from 0.665 to 0.67, distilling at from 500 to C.; it consists of pentane and hexane. P., Galician; in composition, intermediate in position between American and Caucasian petroleum. P. gelatum, petrolatum. P., German, contains benzene hydrocarbons, but consists chiefly of the saturated hydrocarbons and naphthenes. P. Oil, Light, a liquid resembling P. Benzine, having a specific gravity of P., Refined; Kerosene;a product of petroleum by fractional distillation; it boils at from 1500 to 300° C, and has a specific gravity of from 0.78 to 0.82. P. Spirit. Synonym of Benzine.