THE GEOLOGIC MAPS OF WILLIAM MACLURE (1763-1840) - AMERICAN GEOLOGIST

In an editorial footnote published in 1844 in the American Journal of Science, Benjamin Silliman of Yale College christened one William Maclure the Father of American Geology. In 1924 George P. Merrill in The First One Hundred Years of American Geology deemed the years 1785-1819 “The Maclurian Era”. William Maclure, a Scot by birth, was a member of the intellectual and scientific elite of both France and the United States. He was generous in his support of the American Philosophical Society (Philadelphia), the Academy of Natural Sciences, and the American Geological Society serving as President of both the Academy and the Geological Society. Within the geologic community of today the name “Maclure” goes largely unrecognized.

William Maclure actively practiced geology for some 30 years traveling widely throughout Europe and the then United States. He authored three major geological essays, numerous letters-to-the-editor contributions, and what is arguably the first geologic map of the United States. Maclure’s geologic map appeared in six iterations that are little changed from the original 1809 version. Maclure recognized that the complex rocks of the Appalachian Mountain Belt had a geologic history. He further recognized that a geologic map no matter how primitive, was the best way to record, preserve, and transmit the collected data essential in delineating this history. Ostensibly William Maclure’s geologic career ended in 1824 when he joined Robert Owen in the failed attempt to establish a utopian society at New Harmony, Indiana. Maclure died in Mexico in 1840 at the advanced age of 80.

William Maclure the consummate gentleman savant, was a man who hoped to contribute to a science that in time, completely passed him by. Maclure did however, take the first tentative steps in telling the geologic story of the Appalachian Mountain Belt by means of his geologic map(s). Today Maclure's writings are relegated to the arcane studies of the philosophy of science but his maps are avidly sought by antique map collectors. The Father of American Geology has himself, become an historical artifact.