Frank Bursley Taylor
Taylor, Frank Bursley
TAYLOR, FRANK BURSLEY
Taylor was the only child of Fanny Wright and Robert Stewart Taylor. His father, a judge and Republican politician, became wealthy from his practice of patent law, specializing in the new electrical and telephone industries. Judge Taylor’s business and his interest in flood control on the Mississippi River led him to a considerable mastery of science. Frank Taylor graduated from Fort Wayne High School in 1881 and entered Harvard in 1882. He took courses in geology and astronomy as a special student until ill health forced him to drop out in 1886. Accompanied by F. Savary Pearce, a Philadelphia physician, Taylor traveled through the Great Lakes region for the next several years, studying its postglacial geological history. He married Minnetta Amelia Ketchum of Mackinac Island on 24 April 1899. She accompanied him on field trips, driving the horses and, later, their automobile.
Taylor’s father paid his son’s field and publishing expenses until May 1900, when Frank obtained his first job, as assistant to Alfred C. Lane at the Michigan Geological Survey. He then became an assistant in the glacial division of the U.S. Geological Survey from June 1900 to 1916, first under the direction of Thomas Chrowder Chamberlin and then of Frank Leverett. His field assignments were in New England and in the Great Lakes area. In 1908, 1909, and 1911 he mapped the moraines of southern Ontario for the Canadian Geological Survey. The American Associatios for the Advancement of Science awarded Taylor a research grant in 1920 and 1921 to study the New York moraines. Apart from this grant Taylor was again supported by his father’s estate from 1916 to 1938. He was an active member of the Geological Society of America, the Michigan Academy of Sciences, and the AAAs.
Before he joined the U.S. Geological Survey in 1900, Taylor had formulated a history for the Great Lakes region from the period of the fullest extension of the Wisconsinian glaciation through the ice sheet’s retreat to the present time. Between 1892 and 1896 he argued that old beachlines indicated that a marine submergence of the area had followed the disappearance of the glacier, an idea he dropped when his fieldwork of 1895 on the succession of terminal moraines convinced him that the lakes were formed by ice dams instead. Grove Karl Gilbert had encouraged Taylor to study moraines as the crucial test of his submergence theory. Once he accepted the ice dam theory, his reconstruction of Great Lakes history matched current views on this part of the geological record.
Taylor’s studies of beachlines and moraines suggested that retreat of the Wisconsinian glacial field was not steady. Rather, the ice sheet had melted back and then partially readvanced, perhaps dozens of times. Inspired by Chamberlin’s reports from the Greenland expeditions of 1896, Taylor decided that Great Lakes topography had controlled the ice sheet, not the other way around. Once local features in the old Midwest were taken into account, the pattern of retreat and partial readvance was a regular series. Taylor’s work on glacial history culminated in U.S. Geological Survey monograph 53, The Pleistocene of Indiana and Michigan and the History of the Great Lakes (Washington, D.C., 1915), which he wrote with Frank Leverett. This book and Taylor’s articles after 1900 show that his federal government experience led him to use the sophisticated geological terminology that marked a professional scientist.
Taylor’s scheme included a complicated series of drainage systems to remove glacial meltwater. He paid special attention to the time when the main channel was a strait across what is now Lake Nipissing and its related rivers. During the Nipissing episode, he observed, the flow of Niagara Falls was much less than that over the modern ledge, a hypothesis he supported with studies of the narrower gorge of the past. Gilbert had suggested a lesser flow during some part of the postglacial era; Taylor worked on the details and supplied the reason. One important implication of this diminished flow was that the retreat of the falls could no longer be a reliable geochronological indicator.
Taylor was influenced in his glacial work by the publications of Gerhard de Geer as well as by Gilbert and Chamberlin. He adopted de Geer’s concept of an isobase of deformation to describe the uplift of land to the northeast during glacial retreat. Below the isobase no uplift had occurred. Taylor calculated the amount and direction of deformation from the tilting of originally horizontal beachlines of postglacial lakes.
Taylor’s courses in astronomy at Harvard inspired some of his later scientific work. He later recalled that on 13 December 1884, it occurred to him that the moon had once been a comet and had been captured by the earth during its last pass through the solar system. In 1898 he elaborated this idea into a theory for the origin of the whole planetary system. Taylor credited Daniel Kirkwood, then an astronomer at Indiana University, with first publishing a similar theory in connection with the origin of the asteroids. According to Taylor, as comets passed close to the sun, they were captured as planets that spun in the orbit of Mercury. Upon each new capture, the planets shifted out one orbit toward Neptune’s. His fullest explanation of cosmogony appeared in his privately published book (1903) on the subject, in which he spelled out some of the mathematics and physics of the theory. Taylor felt compelled to challenge Isaac Newton’s explanation for the orbit of the moon, because Newton’s system did not rigidly determine the moon’s course. Taylor believed that the orbits of the moons and planets must be determinate, but the mathematics of the situation seems to have been beyond his grasp. It is doubtful that determinate satellite orbits were required for Taylor’s theory.
Taylor’s 1898 work on the planetary system, published as a forty-page pamphlet (now extremely rare), also contained his first articulation of a theory of the history of continents. When the moon was captured by the earth, Taylor argued, it created a tidal force on the planet and increased the earth’s speed of rotation. These two forces pulled the continents away from the poles toward the equator. He did not return to this point in 1903, but in 1910 published his first detailed arguments for a theory of continental drift in a paper on the origin and arcuate shape of Tertiary mountain ranges. He explicitly acknowledged his debt to Eduard Suess’s work on the Asian ranges as a source for much of his theory. Taylor said that as the continents slid toward the equator, they encountered obstructions that created loops of mountian ranges, just as the Wisconsinian glacial sheet had formed lobes as it met local topographical features. Taylor’s theory of 1910 also involved movement of crustal material away from the mid-Atlantic ridge.
Taylor published no papers from 1917 through 1920. He spent those years reading and thinking about ways to defend, expand, and clarify his theory of continental drift and mountain creation. His later papers connected geological phenomena, such as earthquakes, to his theory; added studies of other arcuate Tertiary ranges: and argued that the uplift following the Wisconsinian glaciation could be accounted for by crustal creep. These papers also spelled out the differences of Taylor’s views from those of Alfred Wegener, whose theory of continental drift was first published in 1912. Taylor rejected isostatic adjustment as a mechanism for crustal movement because he believed its working required a fluid interior for the earth. Wegener’s theory used movements toward isoslasy on a fluid subcrust to shift continents, while Taylor’s slid continents along a narrow shear zone of a fairly rigid earth. Taylor’s theory did not fully anticipate the features of plate tectonics, however. The most notable difference is that plate tectonics does not require capture of the moon or other astronomical events to account for earth movements; terrestrial forces are considered adequate.
I. Original Works. Leverett (see below) lists Taylor’s publications but occasionally omits abstracts of articles published in full elsewhere and, in at least two instances, cites pages incorrectly. Two articles should be added to his compilation: “A Short History of the Great Lakes,” in Inland Educator2 (Mar., Apr., May 1896), 101–103, 138–145, 216–223, respectively; and “Geological History of the Great Lakes,” in Scientific Monthly, 49 (July 1939), 49–56. According to the National Union Catalog at the Library of Congress, only two copies of Taylor’s An Endogenous Planetary System. A Study in Astronomy (Fort Wayne, 1898) are in public libraries, one at the John Crerar Library in Chicago and one at the U.S. Geological Survey Library, Reston, Virginia. The Planetary System; A Study of Its Structure (Fort Wayne–London, 1903) is a more accessible account of Taylor’s astronomical theory; and “Bearing of the Tertiary Mountain Belt on the Origin of the Earth’s Plan.” in Bulletin of the Geological Society of America, 21 (1910), 179–226, is a more available statement on the history of continents than the 1898 pamphlet.
II. Secondary Literature. Richard Flint, Glacial and Quaternary Geology (New York, 1971), chs. 2, 13, 21, 30, provides helpful background for assessing Taylor’s work on recent geological history. For useful critiques of Taylor’s theory of continental drift, see Anthony Hallam, A Revolution in the Earth Sciences; From Continental Drift to Plate Tectonics (Oxford, 1973), 3–6, and Ursula Marvin, Continental Drift: The Evolution of a Concept (Washington, D.C., 1973), 63–64.
Biographical details about Taylor are available in Frank Leverett, “Memorial to Frank Bursley Taylor,” in Proceedings of the Geological Society of America for 1938 (1939), 191–200. Shorter sketches are by J. H. Bretz, in Dictionary of American Biography, supp. 2, 653–654; American Men of Science, 5th ed. (1933); Who’s Who in America, 1936–1937, 2387; by A. C. Lane, in Proceedings of the American Academy of Arts and Sciences, 75 (1944), 176–178; by Frank Leverett, in Science, n.s. 88 (5 August 1938), 121–122; and Harvard University, Class of 1886, Secretary’s Report, 7 (1911), 305–307, and 12 (1936), 416–419.
Michele L. Aldrich