Petroleum

(pe-tro'le-um,) PETROL, or ROCK-OIL. [From L. petræ oleum, oil of the rock.] (Min.) A combustible fluid which exudes from the earth in various parts of the world, generally in or near the coal-formations, and is formed during the conversion of vegetable remains into coal, or derived from animal remains, as it is now maintained by some scientists. P. varies greatly in color and consistence, being sometimes thin and pale, at others thick and dark-colored. The substances which mineralogists have distinguished by the names asphaltum, mal tha, P., and naphtha, are thought by some naturalists to be mere varieties of one species; (see NAPHTHA.) Within the last few years abundant supplies ofP. have been obtained from wells and springs in Pennsylvania, New York, and Canada, and the demand for it to serve as an illuminating agent, and for the lubrication of machinery, has created a new and important branch of commerce, innumerable quantities of rock-oil being sold under the names ofP., kerosene, sanoline, leucaline, . The total export from the United States in 1870 was 141,208,155 gallons against 1,500,000 in 1860, and 99,281,000 gallons in 1868, showing an increase of nearly 42,000,000 gallons in two years. The first sale noticed for export was in May, 1861, when 100,000 gallons were sent to foreign markets. Antwerp, which has since led all other ports in the importation of petroleum, took in that year 5,671 gallons, increasing the amount in the following year more than 800,000 gallons. Great Britain took 379,000 in 1861, and in1862 increased her importation to 3,238, 000 gallons. The continued growth of this trade for ten years-from 1,500,000 gallons in 1860 to 141,000,000 in 1870-is a wonderful exhibit, not only on account of the rapid development of the oil interest, but also because the yearly increase has been steady. The daily average product of the l'ennsylvania oil district in December, 1867, was 10,400 gallons; in the same mouth of 1870, it was 15,214 gallons-a fact which shows the inexhaustibility of the wells in that region. In regard to the home consumption, it is estimated that it is equal to one-half the quantity exported-making in round numbers an aggregate consumption of 11,000,000 gallons annually. This enormous amount, reckoning the price at an average of twenty cents per gallon, represents a value of more than $42,000,000 for a single year-certainly a remarkable return for a product unknown to commerce some years ago. [s. 701]