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Biographical Memoirs: Volume 45 (1974)

Chapter: Joseph Hoover Mackin

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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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Suggested Citation:"Joseph Hoover Mackin." National Academy of Sciences. 1974. Biographical Memoirs: Volume 45. Washington, DC: The National Academies Press. doi: 10.17226/568.
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JOSEPH HOOVER MACKIN Novem her Z 6, 1905-A ugust 12, Z968 BY HAROLD L. TAMES DEEP IN THE HEART of Antarctica is a huge windswept plateau that bears the name Mackin Table. It was mapped and so designated by four of Hoover Mackin's former students—Dwight Schmidt, Paul Williams, Willis Nelson, and Arthur Ford—as a tribute to a great teacher of earth science. It is an impressive memorial to a man who was a dominant figure in American geology for more than three decades. Joseph Hoover Mackin was born November 16, 1905, in Oswego, in upstate New York. He was the youngest of seven children of William David Mackin and Catherine Hoover Mackin. His father, who died when Hoover was only seven years old, was of Irish descent, his mother of German descent. Despite the early death of his father and despite the fact that he spent two years immobilized in a cast after being stricken with polio- myelitis at the age of four, Hoover's early years quite evidently were happy ones as the youngest child in a-closely knit family. He outgrew the effects of his childhood illness and developed into a powerfully built youth of great energy. He played football—as a lineman—both at Oswego High School and Oswego Normal School, and between studies and sports he still found time to work at various dons. After graduation from Oswego High School in 1924 and two years at Oswego Normal School, the young Mackin left upper 249

250 BIOGRAPHICAL MEMOIRS New York State to enter New York University. Init tally, he intended to become a journalist, but switched from journalism to geology after hearing lectures by Professor George I. Finley. He received the B.S. degree in geology from NYU in 1930 and then entered the graduate school of Columbia University. His professed major interest at that time was in petrology, but he soon came under the stimulating influence of Professors Douglas Johnson and William Morris Davis, leading American teachers of the science of landforms. From then on, Mackin's course was set: He would become a geomorphologist. He was granted the M.A. degree by Columbia in 1932 and the Ph.D. in 1936. In 1929, at the start of the Great Depression, Mackin was married to Esther Fisk, daughter of longtime friends of the Mackin family in Oswego. In the years following, as a student, he worked at many odd jobs—in a telegraph office, as a painter, as a sandhog in subway construction, and as a tutor. In 1933, however, the young couple achieved a considerable level of affluence as the result of the award to Mackin of a $1,600 fel- lowship. In 1934, after completing all requirements for the doctorate at Columbia other than a thesis, Mackin accepted an appoint- ment as an instructor at the University of Washington, there to begin a distinguished career as a teacher that was to span thirty-four years—twenty-eight years at Washington and six years as Farish Professor of Geology at the University of Texas at Austin. Mackin always considered himself a geomorphologist, though a glance at his bibliography reveals far greater scope to his actual research activities. His doctoral thesis dealt with the origin of surface features of the Big Horn Basin in Wyoming. In it he introduced the concept of lateral planation by a stream essentially at grade, producing gravel-mantled terraces as the stream gradually deepens its valley, as opposed to formation of terraces by stream dissection of earlier alluvial plains.

JOSEPH HOOVER MACKIN 251 Mackin's further analysis led to publication in 1948 of what is the most well-known of his contributions to geomorphology, the classic paper, "Concept of the Graded River." In this paper Mackin refers to "the almost telegraphic rapidity with which the first phases of reaction of a graded stream to a number of artificial changes are propagated upvalley and downvalley"—a warning of profound importance to stream engineers. In later pages of the same paper, Mackin makes the warning more explicit: " . . . the engineer who alters natural equilibrium relations by diversion or damming or channel-improvement measures will often find that he has a bull by the tail and is unable to let go .... " This statement illustrates both Mackin's gift for pithy expression and his willingness to extend the implications of scientific research into the realm of human affairs. Throughout his career, Mackin chose to concern himself with the consequences of man's activities on the natural en- vironment, and he often exerted a little-known but profound influence on proposed developments. He became something of a bete noire to engineers, but to their credit it must be pointed out that he was called upon often for advice. As a small but specific example of his influence, he pointed out that the engineering plan to "save" Ediz Hook, a scenic sandspit on the north side of the Olympic Peninsula, if put into effect, might well result in the complete destruction of Ediz Hook in the next major storm. His private report on the situation resulted in cancellation of the intended work. Clearly, Hoover Mackin was an environmentalist before that term was coined. One of Mackin's earliest papers was written with E. B. Bailey and based on a brief field trip taken while Mackin was still a graduate student and the famous British geologist was in this country on a visit. The paper dealt with the complex fold- ing in the Pennsylvania Piedmont and the use of b-lineation in structural analysis. This paper was perhaps the first attempt to

252 BIOGRAPHICAL MEMOIRS apply the concepts of recumbent folding and nappe structure to geologic interpretation of the Piedmont. Since then, these concepts have been shown to be widely applicable, even though the specific area of the Mackin-Bailey paper remains a subject of controversy, as indicated by Mackin's 1962 "Note" in the Bulletin of the Geological Society of America. A by-product of the initial study was Mackin's 1950 paper on the "down struc- ture" method of viewing and interpreting geologic maps. The principle employed was not new, but nowhere had it been ex- pressed so concisely; it remains required reading for the begin- ning student of structural geology. In World War II, Mackin became affiliated with the U.S. Geological Survey, an organization with which he was to retain close ties for the remainder of his career. As part of the Survey's wartime emphasis on sources of strategic minerals, Mackin studied quicksilver deposits near Morton, Washington, and placer deposits containing radioactive minerals in Idaho. His major effort, however, which continued after the end of World War II, was on the iron deposits of the Iron Springs district of Utah. The results of this study comprise one of the finest con- tributions to the science of ore deposits of the past three decades. The first paper, written within the space of a few days as a guidebook for a Utah Geological Society field conference, almost surely is the most widely referenced informal publication in economic geology literature. In it and in later papers, Mackin demonstrated beyond reasonable doubt precisely where the iron that forms the major economic deposits of the district came from, how it was separated from the parent body of intrusive quartz monzonite, why it was deposited in adjacent limestone in the particular places now found, and when this process took place in the igneous and structural history of the area. In the course of the study, Mackin was to demonstrate that in certain types of magmatic flow, phenocrysts and inclusions become oriented normal, rather than parallel, to the direction of magma

J FOSEPH HOOVER MACKIN 253 movement; a leading authority on granite tectonics ranks the brief guidebook discussion as the most incisive and definitive treatment of the subject of magmatic flow in the English- language literature. That contributions of such significance to the understanding of ore deposits and of granite tectonics could be made by one who classed himself as a geomorphologist, and who disclaimed any competence as a student of economic geology and igneous petrology, must seem remarkable to those who did not know the man. But careful examination of Mackin's papers will reveal that these scientific advances were achieved by the same kind of thinking and analysis he had used in assessing the dynamics of surface processes. The mass of twenty million-year-old quartz monzonite, the source of the ore fluids, was not in Mackin's eyes a dead body: He had the imagination necessary to visualize it during its emplacement as a fluid silicate melt, the ability to analyze its probable behavior and to predict the likely con- sequences, and the observational capacity to locate the critical evidence. Aside from its contribution to granite tectonics, this study remains perhaps the only documented example in world literature of the exact genetic relation between an igneous in- trusion and an associated hydrothermal ore deposit. Mackin's work in the Iron Springs district led him by pro- gressive stages, involving several of his students, into the broader problems of the volcanic and structural history of the Great Basin of Utah and Nevada. An area of some 3,000 square miles was mapped at a scale of 1:62,500 or larger, and an additional 7,000 square miles was mapped in reconnaissance. On the basis of this work, a regional stratigraphy of the ignimbrite sequences was established using a technique based on quantitative mea- surement of phenocryst content. Mackin concluded, in agree- ment with the very early work of Gilbert, that the characteristic block faulting of the area was due to "dominantly vertical dis- placements of comparatively rigid blocks," rather than to com-

254 BIOGRAPHICAL MEMOIRS pressive forces, and he suggested that these movements were a consequence of the withdrawal from depth and surface extrusion of the estimated 50,000 cubic miles of silicic volcanics. In the 1960 paper in which these views were presented is a promise of another paper, "to follow shortly," in which the concept was to be developed more fully; this paper, unfortunately, never ap- peared. Mackin's basic philosophy in scientific endeavor is expressed in his 1963 paper, "Rational and Empirical Methods of Investi- gation in Geology." In it he reveals a basically traditional approach—the "rational" method, patterned after G. K. Gilbert, T. C. Chamberlin, and Douglas Johnson. This method of problem-solving involves a close interplay between observation and deductive reasoning, with emphasis on the use of logic to establish multiple working hypotheses and ultimate definition of the critical diagnostic data required for choice of conclusions. Mackin viewed with considerable skepticism what he referred to as the "empirical" (or "engineering") method, in which emphasis is laid on accumulation and subsequent treatment of large amounts of quantitative data. This often has been taken to mean opposition by Mackin to the quantitative approach in scientific problems, and perhaps the criticism was justified to some extent, particularly when applied to his attitude toward quantification in his own field of specialization, geomorphology. On occasion he was known to dismiss modern developments in geomorphologic research as the work of "numerologists." Yet any examination of Mackin's own research will reveal him to have been a diligent, careful observer. The geologic maps that support Mackin's analysis of ore deposition in the Iron Springs district, for example, are models of detail and accuracy; they are quantitative to a high degree. Mackin's point, however, is that geologic problems, lilac those of biology and other complex sciences, present an almost infinite number of elements sus- ceptible of measurement, and that the "rational" method is

JOSEPH HOOVER MACKIN 255 necessary to select for observation those that are critical. In private conversation, Mackin often spoke disparagingly of the "shotgun" approach to problems, and in his 1963 paper he quotes with approval James Gilluly's statement that "most ex- posures provide answers only to questions that are put to them." Mackin was not basically "antiquantitative"; he simply de- manded of himself and his students that the data-gathering be preceded and continually accompanied by intensive logical analysis of the phenomenon under investigation. As a teacher of earth science, Mackin was almost without a peer during his lifetime. His lectures were models of clarity, and they were delivered with a completely infectious intensity and enthusiasm, whether given to the beginning freshman class or to a group of advanced graduate students. He was remarkably adept at blackboard illustration; with chalk in one hand and eraser in the other he could truly make geologic processes and geologic history come to life. He encouraged divergent views— Provided they were based on good, logical thinking—and de- testect the mere parroting of textbook or classroom notes. In his 1 ~ famous—infamous, to some—course in map interpretation, he surprised students continually with an "A" grade for the wrong answer reached by careful analysis and reasoning, and a "C" or worse for the right answer based on an inadequate or im- proper approach. Logical thinking was paramount, and of necessity the survivor of "map interp" acquired both the ability to think clearly and a thick skin—valuable assets for his pro- fessional years ahead. For Mackin could be cutting in criticism, though always in a way that made it evident that his concern was for the development of the student. Mackin was a gregarious man and typically was the center of discussion croups in the field or at meetings. His views always . . . . ~~ rid were expressed crisply, concisely, and with humor. He loved a good argument and he started many; in one of his papers he remarks that "it is more important that a working hypothesis

256 BIOGRAPHICAL MEMOIRS be provocative than it be right." He was often on the attack— but he attacked ideas, not people, and his vigorous and some- times earthy remarks never left a residue of ill will. Stories of Mackin's personal idiosyncrasies would fill a book— everyone who knew him would have contributions. He was a model train enthusiast and at times had tracks throughout the living areas of his home. He was fearsome at the wheel of a car, generally driving with one hand and waving the other as he analyzed the geomorphology of the rapidly passing terrain to his terror-stricken passengers. He was the proverbial absent- minded professor: He habitually lost or mislaid keys, forgot where he had parked his car, wore mismatched socks (and even shoes), and left personal items strewn from one end of the country to the other. But he was a delight to be with; to use the old cliche, there was never a dull moment when Hoover Mackin was around. In addition to teaching and research, Mackin was extremely active in scientific affairs, even after he was afflicted with cardiac malfunction in the mid-1960's. He was chairman of the Earth Sciences Division of the National Research Council from 1963 to 1965; delegate of the National Academy of Sciences to the 1967 meetings of the International Association of Hydrologists in Istanbul and of the International Union of Geodesy and Geophysics in Zurich in the same year; and he was the keynote speaker at the Symposium on Pediments, held in Budapest early in 1968. He participated actively in the early planning and design of the lunar geology experiments as a member of the U.S. Geological Survey team sponsored by the National Aero- nautics and Space Administration, and he initiated the idea of a sampling tube to be driven into the lunar soil. Throughout his career Mackin was a sought-after speaker; he was a guest lecturer at many universities, and he was the Distinguished Lecturer for the American Association of Petroleum Geologists in 1953 and National Lecturer for Sigma Xi in 1963. Mackin

JOSEPH HOOVER MACKIN 257 was a member of the National Academy of Sciences, the Geo- logical Society of America (Council, 1950-1953; chairman of Cordilleran Section, 1950), the Society of Economic Geologists, the American Geophysical Union, the American Association of Petroleum Geologists, the American Association for the Ad- vancement of Science, and Sigma Xi. Mackin died on August 12, 1968, at the height of his career and while preparing to serve as delegate of the U.S. National Committee on Geolo~v to the International Geological Con- - A, gress to be held in Prague later in 1968. He is survived by his widow, Esther Fisk Mackin; a daughter, Barbara Catherine Barker, wife of Dr. Daniel Barker, of the geology department of the University of Texas; a son, Robert Fisk Mackin, a design engineer; and two granddaughters. WISH to acknowledge and to express my gratitude to those who have aided me in the preparation of this memoir: Esther Fisk Mackin on family details; Arthur B. Ford, Peter B. Rowley, Paul L. Wil- liams, W. W. Rubey, and John T. Hack on professional aspects; and Birdena Schroeder, departmental secretary at the University of Texas, for biographic and bibliographic material.

258 KEY TO ABBREVIATIONS BIOGRAPHICAL MEMOIRS BIBLIOGRAPHY Am. l. Sci.—American journal of Science Bull. Geol. Soc. Am. = Bulletin of the Geological Society of America J. Geol. - Journal of Geology U.S. Geol. Surv. Bull. = United States Department of the Interior, Geo- logical Survey, Bulletin U.S. Geol. Surv. Profess. Paper = United States Department of the Interior, Geological Survey, Professional Paper U.S. Geol. Surv. Trace Elem. Memo. Rept. = United States Department of the Interior, Geological Survey, Trace Elements Memorandum Reports Wash. Dept. Conserv. Div. Mines Geol. Rept. Invest. = Washington Depart- ment of Conservation, Division of Mines and Geology, Report of Investi- gat~ons 1933 Evolution of the Hudson-Delaware-Suscluehanna drainage. Am. i. Sci., 5th ser., 26:319-31. 1934 Terraces in the Susquehanna Valley below Harrisburg, Pennsyl- vania. Science, 80: 140-41. 1935 Problem of the Martic Overthrust and the age of the Glenarm Series in southeastern Pennsylvania. I. Geol., 43:356-80. 1936 method of mounting maps. Science, 84:233-34. The capture of the Graybull River. Am. l. Sci., 5th ser., 31:373-85. Susquehanna River terraces. International Geographical Congress, Warsaw, 1934, Sec. II, Tome 2:524-28. 1937 Erosional history of the Big Horn Basin, Wyoming. Am., 48:813-94. With E. B. Bailey. Recumbent folding in the Pennsylvania Pied- mont: preliminary statement. Am. T. Sci., 5th ser., 33:187-90. Bull. Geol. Soc. 1938 The origin of Appalachian drainage: a reply. Am. J. Sci., 5th ser., 36:27-53.

JOSEPH HOOVER MACKIN 259 1940 With H. P. Hansen. A further study of interglacial peat from Washington. Bulletin of the Torrey Botanical Club, 67: 131-42. 1941 A geologic interpretation of the failure of the Cedar Reservoir, Washington. Bulletin of the University of Washington Engi- neering Experiment Station, 107, 30 pp. Drainage changes near Wind Gap, Pennsylvania. A study in map interpretation. journal of Geomorphology, 4:24-53. Glacial geology of the Snoqualmie-Cedar area, Washington. I. Geol., 49:449-81. lg44 Relation of geology to mineralization in the Morton cinnabar dis- trict, Lewis County, Washington. Wash. Dept. Conserv. Div. Mines Geol. Rept. Invest., Vol. 6, 47 pp. 1945 With H. A. Coombs. An occurrence of "cave pearls" in a mine in Idaho. I. Geol., 53: 58-65. 1947 Altitude and relief of the Big Horn area during the Cenozoic. In: Guidebook for Field Conference in the Big Horn Basin, pp. 103-20. Wyoming Geological Association. Some Structural Features of the Intrusions in the Iron Springs District. Guidebook to the Geology of Utah No. 2. Utah Geo- logical Society. 62 pp. 1948 Concept of the graded river. Bull. Geol. Soc. Am., 59:463-512. 1949 With H. P. Hansen. A pre-Wisconsin forest succession in the Puget Lowland, Washington. Am. I. Sci., 5th ser., 47:833-55. 1950 The down-structure method of viewing geologic maps. J. Geol., 58:55-72.

260 BIOGRAPHICAL MEMOIRS 1952 Reconnaissance geology of the monazite placers of the Long Valley district, Idaho. U.S. Geol. Surv. Trace Elem. Memo. Rept. 473, 22 pp. 1953 Iron ore deposits of the Iron Mountain district, Washington County, Idaho. U.S. Geol. Surv. Bull. 982-E:121-51. Reconnaissance geology of placer deposits containing radioactive minerals in the Bear Valley district, Valley County, Idaho. U.S. Geol. Surv. Trace Elem. Memo. Rept. 602, 35 pp. Stream planation near Colorado Springs, Colorado. Bull. Geol. Soc. Am., 64:705-10. 1954 Geology and iron ore deposits of the Granite Mountain area, Iron County, Utah. U.S. Geol. Survey Mineral Investigations Field Studies Map, ME 14. 1956 With D. L. Schmidt. Uranium- and thorium-bearing minerals in placer deposits in Idaho. U.S. Geol. Surv. Profess. Paper 300: 375-80. 1960 With Earl Ingerson. An hypothesis for the origin of ore-forming fluid. U.S. Geol. Surv. Profess. Paper 400:B1-B2. Structural significance of Tertiary volcanic rocks in southwestern Utah. Am. I. Sci., 5th ser., 58:81-131. Geomorphology. In: McGraw-Hill Encyclopedia of Science and Technology, pp. 172-73. New York, McGraw-Hill Book Co., Inc. 1962 A strat~graphic section in the Yakima Basalt and Ellensburg For- mation in south-central Washington. Wash. Dept. Conserv. Div. Mines Geol. Rept. Invest., No. 19, 45 pp. Structure of the Glenarm Series in Chester County, Pennsylvania. Bull. Geol. Soc. Am., 73:403-09.

J OSEP H H O O VER M A CKIN 1963 261 Rational and empirical-methods of investigation in geology. In: The Fabric of Geology, ed. by C. C. Albritten, Jr., pp. 135-63. Reading, Mass., Addison-Wesley. Reconnaissance stratigraphy of the Needles Range Formation in southwestern Utah. In: Guidebook to the Geology of South- western Utah, ed. by E. B. Heylmun, pp. 71-78. Salt Lake City, Intermountain Association of Petroleum Geologists. 1964 The development of geomorphology. 1965 Science, 146:1665-66. With E. M. Shoemaker, E. N. Goddard, H. H. Schmitt, fir., and A. C. Waters. Geological field investigation in early Apollo manned lunar landing missions. United States Geological Survey, Re- port to NASA. 92 pp. With A. S. Cary. Origin of Cascade landscape. Washington Di- vision of Mines and Geology, Information Circular 41, 35 pp. 1966 With P. L. Williams. Guidebook to stratigraphy of Tertiary vol- canic rocks, Cedar City, Utah to Las Vegas, Nevada. Geological Society of America Field Trip No. 8, Las Vegas meeting, 1966. 1967 Citation presentation of Penrose Medal to Philip B. King. Pro- ceedings for 1967, Geological Society of America, pp. 75-77. With H. R. Blank, in Geologic interpretation of an aeromagnetic survey of the Iron Springs district, Utah. U.S. Geol. Surv. Profess. Paper 516-B, 14 pp. 1968 Iron ore deposits of the Iron Springs district, southwestern Utah. In: Ore Deposits of the United States, 1933-1967, ed. by J. D. Ridge, pp. 992-1019. New York, American Institute of Mining and Metallurgical Engineers.

262 Origin of lunar maria. BIOGRAPHICAL MEMOIRS 1969 Bull. Geol. Soc. Am., 80:735~7. 1970 Origin of pediments in the western United States. In: Problems of Relief Planation, ed. by M. Pesci, pp. 107-11. Budapest, Akad. Kiad6. With D. L. Schmidt. Quaternary geology of Long and Bear valleys, west-central Idaho. U.S. Geol. Surv. Bull. 1311-A, 22 pp.

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Biographic Memoirs: Volume 45 contains the biographies of deceased members of the National Academy of Sciences and bibliographies of their published works. Each biographical essay was written by a member of the Academy familiar with the professional career of the deceased. For historical and bibliographical purposes, these volumes are worth returning to time and again.

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