ADAMS, LEASON HEBERLING

(b. Cherryvale, Kansas, 16 January 1887; d. Bethesda, Maryland, 20 August 1969)

geophysics.

Adams was the son of William Barton Adams and Katherine Heberling Adams. Educated in a one-room schoolhouse in the farm belt of central Illinois, Adams entered the University of Illinois at the age of fifteen and graduated in 1906 with a B.Sc, degree in chemical engineering.

After two years as a chemist with Morris and Company of Chicago and the Missouri Pacific Rail-road in St. Louis, Adams became a member of the Technologic Branch of the U.S. Geological Survey in Pittsburgh. In 1910 he began a career at the Geophysical Laboratory of the Carnegie Institution of Washington, becoming its acting director (1936–1937) and director (1938). After retirement in 1952. Adams continued research as a consultant to the director of the National Bureau of Standards, then accepted an invitation from the University of California at Los Angeles to become visiting professor (later professor in residence) of geophysics at the Institute of Geophysics and Planetary Physics. He returned to Washington in 1965, when failing eyesight made further experimental work difficult.

Adams married Jeanette Maude Blaisdell of St. Louis in 1908; they had four children: Leason Blaisdell, William Muirhead, Madeline Jeanette, and Ralston Heberling. After forty-six years of “harmonious partnership,” Jeanette Adams died. Adams married Freda R. Ostraw in July 1956; they lived in Pacific Palisades, California, until 1965.

Adams was active in formal organizations such as the Philosophical Society of Washington, the Chemical Society of Washington, the Geological Society of Washington, the Washington Academy of Sciences, and the American Geophysical Union, serving as president of each, as well as more socially oriented scientific clubs, such as the Metachemical Club, the Pick and Hammer Club, and the Cosmos Club, He was an early radio enthusiast, building receivers as the technology advanced. He also designed and supervised the building of two homes, managed a sizable formal flower garden, played golf regularly, built his own sailboat, and contributed to the blazing of a portion of the Appalachian Trail with his colleague J. Frank Schairer.

From 1910 to 1916 Adams was the research associate of John Johnston, who was studying the effects of pressure and temperature on physicochemical systems of importance to geology. He helped design and construct an apparatus for making measurements at pressures up to 2 kilobars and 400°C, the highest conditions achieved simultaneously at that time. They measured the effect of pressure on the melting points of metals, on density, and on the physicochemical behavior of simple solids. In the course of these experiments Adams and Johnston produced new calibration curves for the copper-constantan and the platinum-platinumrhodium thermocouples that were in “remarkable concordance” with the resistance thermometer measurements of the National Bureau of Standards and the nitrogen-gas thermometer at the Geophysical Laboratory.

With the onset of World War I, the sources of opticalglass in Germanywere cutoff; and the Geo-physical Laboratory, because of the expertise of its staff in phase equilibria studies on glass-forming silicate systems, accepted the task of developing optical glasses. One of the principal problems to be solved was the annealing of the formed glasses. Adams and Erskine D. Williamson invented an annealing method based on heat transfer theory that was particularly useful for large blocks. The procedure was successfully applied to the fabrication of the two-hundred-inch mirror for the Mount Palomar telescope. His interest in cooling problems was eventually applied to the earth itself, and in 1924 he published “Temperatures at Moderate Depths Within the Earth,” Adams also laid the foundation for the important conclusion that the earth, while solidifying as a magma (silicate liquid), crystallized from the bottom upward, thereby furnishing a reasonable explanation for the segregation of the elements abundant in the crust.

After World War I, Adams turned his attention to the measurement of the elastic constants of rocks at 25°C under high (2–12 kilobars) pressures, He solved the porosity problem in natural rocks by sealing the specimens in a thin metal jacket and immersing the jacketed specimen in an organic fluid. The volume change, measured by piston displacement, was used to calculate the compressibility. More important. Adams, again with Williamson, related the compressibility and density of the rock to the seismic velocities of the primary and secondary waves. By comparing the velocities deduced in the luboratory with those measured in the earth, Adams was able to identify the kinds of rocks with the appropriate elastic properties (for instance, peridotile and eclogite) that might occur deep in the crust of the earth.

A self-taught student of thermodynamics, Adams was persuaded that the validity of those relationships could be tested only in the laboratory. In a series of papers with Ralph E. Gibson he accurately measured the thermodynamic properties of systems such as NaCl–H₂O, K₂SO₄–H₂O, and NH₄NO₃–H₂O. In addition, as a result of his investigations on equilibria of aqueous solutions under pressure with various solid phases, in 1936 he provided the first complete definition of the activity function proposed by Gilbert N. Lewis.

With his acceptance of the duties of the director of the Geophysical Laboratory of the Carnegie Institution of Washington in 1936, Adams gave full attention to administration. During World War II he was appointed chairman of Division I (ballistics) of the Office of Scientific Research and Development, directed by Vannevar Bush. The task was to investigate the erosion of gun barrels resulting from the action of hot propellant gases under high pressure. The team he assembled produced significant results that led to improvements in ordnance. Some of the metals developed were later used in pressure vessels by staff members of the Geophysical Laboratory to investigate hydrothermal systems important to petrologs. At the close of World War II he instituted a comprehensive review of the Geophysical Laboratory’s programs and greatly strengthened those involving controlled experimental studies.

After retiring from the Geophysical Laboratory, Adams resumed experimental studies at the University of California at Los Angeles, where his principal interests were the kinetics of transitions and polymorphic changes under pressure. He never lost his interest in thermodynamics; his last paper was titled “Enthalpy Changes as Determined from Fusion Curves in Binary Systems.”

Recognition of Adams’scientific abilities include the Edward Longstreth Medal of the Franklin Institute in 1924, lor his research on the annealing of optical glass; an honorary Sc.D. from Tufts University in 1941: the Presidential Medal for Merit in 1948, for his contributions to the war effort; the Bowie Medal, the highest award of the American Geophysical Union, in 1950; and election to the National Academy of Sciences in 1954. In addition. he held honorary memberships in the Royal Astronomical Society (London), Sigma Xi, and Phi Lambda Upsilon.

BIBLIOGRAPHY

I. Original Works. Adams’ writings include “The Influence of Pressure on the Melting Points of Certain Metals,” in American Journal of Science. 4th ser., 31 (whole no. 181) (1911), 501–517. written with John Johnston; “On the Lffeet of High Pressures on the Physical and Chemical Behavior of Solids,” ibid., 35 (whole no. 185) (1913), 205–253, written with John Johnston: “The Annealing of Glass,” in Journal of the Franklin Institute, 190 (1920), 835–870. written with Erskine D. Williamson: “On the Compressibility of Minerals and Rocks at High Pressures,” ibid., 195 (1923), 475–529. written with Erskine D. Williairson: “Temperaturies at Moderate Depths Within the Earth.” in Journal of the Washington Academy of Sciences, 14 (1924), 459–472: “The Compressibilities of Dunile and of Basalt Glass and Their Bearing on the Composition of the Earth,” in Proceedings of the National Academy of Science. 12 1926), 275–283. written with Ralph E. Gibson: “The Melting Curve of Sodium Chloride Dihydrate. An Eperimental Study of an Incongruent Melting at Pressures up to Twelve Thousand Atmospheres,” in Journal of the American Chemical Society, 52 (1930), 4252–4264, writlen with Ralph E. Gibson: “Equilibrium in Binary Systems Under Pressure. I. An Experimenial and Thermodynamic Investigation of the System NaCl-H₂O at 25°, ibid., 53 (1931), 3769–3813; “A Method for the Precise Meastnement of Optical Path-Difference. Especially in Stressed Glass,” in Journal of the Franklin Institute, 216 (1933), 475–504, written with Roy W. Goranson; “A Note on the Stability of Jadeite,” in American Journal of Science. 216 (1933)., 299–308: and “Enthalpy Changes as Determined from Frison Curves in Binary Systems,” ibid., 264 (1966), 543–561, written with Lewis H. Cohen.

An autobiographical article is “Adams. Leason Heberling,” in Modern Men of Science, I (New York. 1966), 1–2.

II. Secondary Literature. A complete bibliography of Adams’ works is in Ralph E. (iihson. “Leason Heherling Adams,” in Biographical Memoirs. National Academy of Sciences, 52 (1980). 3–33. See also Merle A. Tuve. “Twelfth Award of the William Bowie Medal Citation,” in Transactions of the American Geophysical Union, 31 , no. 3 (1950). 341–343.

H. S. Yoder, JR.