Black gold is an informal term for oil or petroleum—black because of its appearance when it comes out of the ground, and gold because it made everyone involved in the oil industry rich. The oil industry in the United States began in 1859 when retired railroad conductor Edwin L. Drake (1819–1880) drilled a well near Titusville, Pennsylvania. His drill was powered by an old steam engine. Oil from animal tallow and whales were used as lubricants since colonial times. A process for deriving kerosene from coal oil was not patented until 1854. (Kerosene is a clean-burning and easy-lighting fuel.)

After Drake's Titusville well produced shale oil the substance was analyzed for its properties and it was determined to be an excellent source of kerosene. Soon others began prospecting for "rock oil" and western Pennsylvania became an important oil-producing region. Wagons and river barges transported barrels to market, though later the railroad reached into the region and, by 1875, a pipeline was built to carry the oil directly to Pittsburgh.

Petroleum soon replaced whale oil as a fluid for illumination. During the 1880s the states of Ohio, Kentucky, Illinois, and Indiana also produced oil. In 1901 the famous Spindletop field in eastern Texas provided the nation's first "gusher" (a site where oil literally shoots out of the earth.)

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