The principal product of the oil in the 19th century was kerosene, which quickly replaced whale oil for illuminating purposes in the United States. Originally dealing in whale oil which was widely used for illumination, Charles Pratt (1830–1891) of Massachusetts was an early pioneer of the natural oil industry in the United States. He was founder of Astral Oil Works in the Greenpoint section of Brooklyn, New York. Pratt's product later gave rise to the slogan, ""The holy lamps of Tibet are primed with Astral Oil"." He joined with his protégé Henry H. Rogers to form Charles Pratt and Company in 1867. Both companies became part of John D. Rockefeller's Standard Oil in 1874.