Edwin Theodore Dumble, geologist, the son of James F. and Mary A. Dumble, was born in Madison, Indiana, on March 28, 1852. Three months after his birth his family moved to Galveston. He was educated at Groce's plantation and the Houston Academy and attended Washington and Lee University, where his college education was interrupted when his father's cotton mills were destroyed by fire. He served as a bookkeeper for a lumber firm for two years and returned to school but was again forced to withdraw when the company failed. He eventually received a diploma in the School of Mathematics, Astronomy, and Chemistry and in 1912 a B.S. degree in mining engineering; in 1924 he received a doctorate of science from Washington and Lee.
Dumble returned to Houston and worked as a car accountant for the Houston and Texas Central Railway, devised a system for handling car records, and first considered the possibility of using lignite as a locomotive fuel. Eyestrain eventually forced him to retire to Llano, where he worked in a drugstore and assay office and developed his interest in geology. On June 15, 1876, he married Fanny Boswell Grey; the couple had two children. From 1874 to 1887 he assisted in his father's mercantile business in Houston as manager and buyer for glassware and china and served as consulting accountant for various firms. He also reported on water supplies for the city of Houston and conducted experiments at a small private chemistry laboratory on the use of Texas lignite as a cheap industrial fuel. Dumble served as Texas State Geologist from 1887 to 1897 and was responsible for directing the third Texas Geological Survey beginning in 1889. Beginning in 1897 he was a consulting geologist for the Southern Pacific lines. He was among the first to organize a department devoted to petroleum exploration and first applied micropaleontology in the search for subsurface structures. As a vice president of the Southern Pacific oil company subsidiaries, the Rio Bravo Oil Company and the East Coast Oil Company, he was active from South America to China and Alaska.
Dumble's first paper, "Nacogdoches Oil Field," appeared in the Geological and Scientific Bulletin of the Texas State Geological and Scientific Association of Houston, which he founded in 1884. He published some seventy scientific papers in all, and also wrote Brown Coal and Lignite (1891) and The Geology of East Texas (1920). He was a fellow of the Geological Society of America and the American Association for the Advancement of Science and was president of the Texas Academy of Science (1893–94). He was a member of the American Institute of Mining Engineers, the Mining and Metallurgical Society of America, the American Association of Petroleum Geologists, and the California Academy of Science. Dumble retired to Hanover County, Virginia, where by 1926 he had developed pernicious anemia. He died of leukemia on January 16, 1927, and was buried in the English cemetery at Nice.