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Biographical Memoirs: Volume 53 (1982)

Chapter: David Locke Webster II

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Suggested Citation:"David Locke Webster II." National Academy of Sciences. 1982. Biographical Memoirs: Volume 53. Washington, DC: The National Academies Press. doi: 10.17226/576.
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DAVID LOCKE WEBSTER II November 6, 1888-December ~ 7, 1976 BY PAUL KIRKPATRICK THE LIFE to be reviewed here was that of a professional physicist, an educator, a national servant, a family man, and a keen appreciator of the natural earth—its rock, its air, its water, and its celestial environment. He was avid about his hobbies and always macle science out of them by studying them in productive depth. Near the encI, he said that he should have specializes] in geology rather than physics, but few physicists would second this tardy preference. As with able and versatile men in general, there was a variety of good lives open to Webster; like them all, the path actually chosen was a function of the elaborate complex of unpredictables that we must call "chance." David Webster was born in Boston, ant! New England was stamped on his tongue to the end, as any ear for dialect wouIcI recognize, but it would be wrong just to pronounce him a New England type except as it was typical of nineteenth- century New Englanclers to resist complete uniformity. Webster had such individuality or self-dependence. To his students he was a "character," but that tells nothing precise since characters defy characterization. FAMILY DATA Each of Webster's parents was anteceded by at least seven generations of New England ancestors, the regressing lines 367

368 BIOGRAPHICAL MEMOIRS vanishing at about the mid-seventeenth-century peak of immigration from Britain. All of the names seem English, and Webster has ciroppecl a remark that his ancestors were Puritans from the northeast part of England Yorkshire, Norfolk, and thereabouts and that they left Englancl, bounct for America, about two jumps ahead of the sheriff. If this reference hac! any other than a facetious meaning, it should be realizes! that there must then have been some two hundred and fifty unconnected ancestors in the migratory flow that generated our subject, and it is unlikely that one denigration couIct fit them all. The Webster name is best remembered in Massachusetts history because of two individuals. One of them (Daniel) shared a seventeenth-century ancestor with our subject. The other (Noah) was on an unrelated! line. Webster's father, Andrew Gerrish Webster, deprived of a college education by Civil War conditions, was of the type capable of self-education. His recorcled description of him- self was "Tastes simple self-containecI." His wife, Webster's mother, scorned this modesty and pointed out some of his valued services in the community of Boston, the center of his business interest, which was the tanning and wholesale clistri- bution of leather. Webster's mother was born Lizzie Florence Briggs in Boston in IS53. The Briggs name had been known in the shipbuilcling business for more than two centuries, but in the middle of the nineteenth century steamships had improved to the point where they couicl cirive the windjammers off the oceans. I,izzie's father (Harrison Otis Briggs) gave up the contest, mover! his family to England, ant! got himself a job in a shipyard in Liverpool. There Lizzie got most of her schooling. For reasons unknown, the family returned to America after a dozen years, and Webster picks up the story at that point.

DAVID LOCKE WEBSTER II 369 By the time the family returned to the United States the old square-rigged sailing ships were almost a thing of the past, and my grandfather never had built steamships. So Grandpa Briggs went into a bank instead of going back into shipping. As President of the Bank of the Republic in Boston he had a prominent part of some kind in the reconstruction of the South after the Civil War. He was very definitely not a carpetbagger. His work was entirely altruistic, and just what he did there I am not sure, but I know it was for the benefit of the Southerners. My mother once described her father as having "great sweetness and unselfishness, with dignity and reserve. . . a clear and quick brain, great kindness of heart and a sense of humor, very fond of music, literature, travel, and outdoor sports."* Webster's father left his Boston leather business about 1910 at an age now considerecI appropriate for retirement, but he had other interests to follow, particularly real estate. He worked until his death at ninety-three. His son has citec! evidence that at that age he was still "a keen man." There is also evidence that prolonged physical and mental health were Webster family characteristics, traits borne out by David Locke the second. CHILDHOOD Raising the young Webster from his tweIve-pound birth weight to his teens was a project shared by numerous loving and unskilled hands. In his last decade of life, the product of their efforts testified: "I grew up practically alone [though he had a beloved elcler brother who hac! been brought along under a different formula]. My childhood was deadly un- interesting. ~ was not allowect to play with other children because it was feared ~ might catch germs of one kind or another." ~ When first sent to school at age five, he was completely surprised by the discovery of what it was like to play with * Personal journal of David Locke Webster II, n.d. t Ibid.

370 BIOGRAPHICAL MEMOIRS other children. His playmates found that he was under motherly orders to keep his hat on (to avoid fatal pneu- monia), so naturally they knocked it off. "It was a completely wrong introduction to clearing with humanity, and ~ don't think I have ever really recoverer! from it,* he said in his eighty-seventh year. Had Webster's career been steered by modern aptitude tests, he would never have become a physicist, for, as he confessed in later life, his most clifficult elementary subject was arithmetic. His later high-level aptitude for mathematics first became perceptible in the later courses of algebra and geometry, subjects that he found easy and fun. Other detester! experiences of Webster's schooling phase were compulsory dancing lessons (from about age eight), compulsory piano lessons (beginning at about ten and com- pletely ineffective), ant! school athletics. He likes] bodily activity and suffered from no handicapping physical disabili- ties, but he was cleadly sick of being regimented in every way and came to the point of automatically opposing any new thrust of it. Another form of systematic observance, which began in early childhood but never pair! off to the satisfaction of those who administered it, was religious training. Perhaps it would have been more effective had it not been so competitive. He has written that he was "dragged every Sunday to one church or another. . . Land] . . . all through the Episcopal Sunday School,"T but on weekdays there were other pressures. His scholarly and respected paternal grandfather, a devoted Swedenborgian, bore as much responsibility, by family agree- ment, for the boy's upbringing as did his mother. In David's early years his mother's time was taken up by "social duties," and he spent most of his time with nursemaids, all Irish * Ibid. t Ibid.

DAVID LOCKE WEBSTER II 37 Catholic, anti, it appears, as much concerned with the welfare of his soul as with that of his body. EDUCATION AND RELATED MATTERS Such experiences were not without later effect. Early warning about Robert Ingersoll drew him into broadening critical reading. Association with his grandfather led him to appreciate Emanuel Swedenborg as a great scientist consider- ably ahead of Kant and Laplace on some discoveries. Webster's obligatory Sunday morning studies of the Episcopal Book of Common Prayer and the Creed made wonderful material for swearing, and he developer! an ability at pic- turesque profanity that stayed with him for life. Ricliculing religion is a simpler course of action than try- ing to think it out, and Webster's ironic experiences did not leave him an impious scoffer but a thoughtful agnostic who would sneak attendance at a Catholic mass, to see what it was like, when grouncled on some long solo flight. After a sailing or flying near-miss he confessed that he could thank God without believing in him. When required to fill out a "re- ligious preference" blank he would profess agnosticism. In a later year at Stanford, on his morning walks to the Quad, he developed a good acquaintance with his neighbor, the university chaplain. These peripatetic philosophers wasted little time on trivialities and subsequently the chap- lain, an inveterate author, expressed in the frontal pages of a book his gratitude for aid received from "Dr. David Webster, ctistinguishect atheist of Stanford University." Until he went to a teaching post at the University of Michi- gan in his twenty-eighth year, Webster had tract no ex- perience of public education. His own schooling was in Boston private schools, finishing for Harvard at Noble Sc Greenough's Classical School. Webster himself wrote "I went from there to Harvard because in those clays no one with my

BIOGRAPHICAL MEMOIRS 372 background and upbringing would have thought of going to college anywhere else." ~ There is nothing to be found in Webster's papers about his undergraduate years at Harvard and almost nothing in the possession of his family. He came through in the usual four years with the much less usual summa cum laude. He seems to have been less than completely satisfied with his record and to have grieved over the presence there of a single C grade. His mother appealed to the Harvard administration about the disgraceful C and had to be satisfied with the decIa- ration that there was nothing higher that the College could give than a summa cum laude, but if the defeated gladiator would present himself at the president's office, that official would publicly put a wreath of laurel and roses on his brow. It is comforting to know that this record did not denote any complete life switch to middle-of-the-road conformities. It surprises this reviewer of his life to find that the child non- conformist could so abruptly convert to conventional aca- demic ideals of performance and aspiration. RESEARCH BEGINNINGS Following graduation Webster went on for the doctorate, working principally under the direction of veteran Professor Theodore Lyman on the optical properties of chlorine gas, a rather unexciting classical field that did not firmly hold his interest beyond the three years of degree work. Phrases like "modern physics" and "atomic physics" were resounding in the halls of science and young searchers and researchers recognized that the old classical fields no longer offered the maxima of either the prizes or the fun. Webster selected the field of X-ray physics, and it was to be the area of his chief research effort for three decades. With his new degree he *IBM.

DAVID LOCKE WEBSTER II 373 received appointment to an instructorship. He assembled X-ray equipment and went to work on problems of his own choosing. A brief flashback is necessary here. The three gracluate- stuclent years were not unmitigated labor: In 191~ Webster met and in 1912 married Anna Cutler Woodman. Little is known about this romance, but he has recorded that he was drawn to her because, unlike most of the girls he knew, she was training herself to do something, to become a teacher. Another strong plus for Anna was that she was just the kind who wouIcI like a honeymoon on a sailboat, sharing with him his most beloved avocation. In another year, their family of two girls anti two boys started coming. Back at the research laboratory there were interesting developments. Throughout the first clecade of this century, X-rays were used but not unclerstooc3. Not until 1912 was it uniformly agreed that these rays were waves much like ordinary light and not showers of submicroscopic bullets. As waves, they were in the field of the spectroscopist, but none of his instruments could disperse them or measure their wavelengths. The spectrometer that could do these things had been invented by W. Lawrence Bragg, who used a crystal in place of the familiar prism or grating, and so opened up the science of X-ray spectroscopy. Webster, with some shop aicI, put together an X-ray spec- trometer on the Bragg pattern and got started observing the nature of the spectra emitted by the then recently available glass X-ray tubes developed for medical use. He could iclen- tify the range of wavelengths the tube emitted when in high- voltage operation, and he could measure in an approximate manner the relative output strengths of the different wave- lengths he chose to observe. Before going further with the laboratory data, we inter- polate. Experimenters had concluded, before spectrometers came to their aicI, that the X-ray power put out by the com-

374 BIOGRAPHICAL MEMOIRS mon tubes comprised a wide variety of wavelengths. It was evident that electrons in the evacuated tube were accelerated to high speeds by an applied and measurable voltage but were then abruptly stopped by their impact upon a metal target (in this case, of tungsten). The observed X-rays radiated out from the spot on the target where the electrons collided, so one had to suppose that the X-rays got their energy from what the electrons surrendered when they were stopped. But it would have been rash to suppose that all of the electron kinetic energy reappeared as radiation energy. Such uncertainties had a serious importance since these were days when the old quantum theory was out on trial. It grew in credibility as it was found applicable to more phe- nomena. Here was a relatively uncluttered phenomenon in- volving electrons and a kind of light, a sort of reverse of the phenomenon of photoelectricity, which had been greatly clarified by the application of quantum concepts, particularly the doctrine that light, though demonstrably a kind of wave, dealt out its energy in little mutually exclusive packets. Phy- sicists uncounted had wondered if something of the kind were involved in the X-ray tube. Finding out would require, among other things, quantitative X-ray measurements such as a Bragg spectrometer might facilitate. Professor William Duane, very senior to Webster in the Harvard science escalator, was well aware of the theoretical problems in the X-ray field and of possible modes of solution. He borrowed Webster's spectrometer and assigned one of his younger men, Franklin C. Hunt, to explore with it the con- tinuous X-ray spectra of tungsten, making careful records of the voltages used to accelerate the electrons. The investiga- tion was a brilliant success, showing that the spectrum was abruptly terminated at its high-frequency end and that the terminal frequency there fitted into the famed Planck- Einstein energy formula, which equates the energy of an

DAVID LOCKE WEBSTER II 375 electron to that of a radiation particle (or, as we came to say later, to the energy of a photon). Professor Duane promptly reported these findings to a meeting of the American Physical Society and the news went round the worIcI under the title of the law of Duane and Hunt, and so it is still known and clescribec! in many a book on many a library shelf. What the world did not know and found out only very recently is that the Duane-Hunt experiment had been con- ceivecl, nicely performed, and recorcled (but not publicizecl) earlier by David Webster. Now the writer of this memoir must switch to the first person. ~ worked beside Webster at Stanford University for more than a decade and talked with him occasionally about scientific matters for three decades more. There was much talk about X-rays, but never did he tell me of his anticipation of Duane and Hunt. I clo not know why. I came to know of it only because Webster was a meticulous recorder. In his postmortem effects were an uncounted number of loose-leaf ring binders—certainly between one and two huncTrecI- among which I found his Harvard research notes. They show that he knew exactly what he was doing on March 3l, 1915, when he gathered data on the tungsten continuous spectrum, plotted a curve, noted that it terminates! on the shortwave sicle, and calculated therefrom a good value of the Planck constant h. He was aware that he had been scooped, and I do not understand why he clid not try to salvage what glory was possible later. Young scientists upward bound are expected to put their best feat forward. HacI he been as skillet] or as well motivated in the matter of public relations as he was in * For a discussion of David Webster's work in this connection, see P. Kirkpatrick, "Confirming the Planck-Einstein equation h v = ( i/2)mv2," American f ournal of Physics, 48( 10):803~.

376 BIOGRAPHICAL MEMOIRS scientific performance ant! recording, the law of Duane and Hunt might have been Webster's law all these years. WORLD WAR I From Harvard, Webster went in 1917 to an assistant pro- fessorship in the University of Michigan, which turned out to be but his entrance vestibule to WorIct War I, the first of two wars in which he was destined to rencler scientific service. He was caught in the general ctraft, but fount} a more useful and attractive occupation in the air service of the Army Signal Reserve Corps. He was not a flyer himself at this stage, but requested and got flight instruction. Here began a personal enthusiasm comparable to that which he had always felt, and possibly inherited, for sailing. His responsibilities started with the testing of flight instruments but progressed rapidly to testing and criticism of the many products of the suciclenly created military airplane industry, and also of foreign planes. He has been called the first test pilot in American air service, but he later declined this ctistinction, since there was then no such recognized title. His flight instruction took place at Gerstner Fielc! (Louisiana) where he had been sent to have charge of the measuring instruments intenclecT for use in tests of the Amer- ican modification of the British DH4 airplane. Though aware of his defective hearing and apprehensive about a tendency to airsickness, Webster mastered flying promptly and was told by his French instructor, "Mon Dieu! You fly like ze God Himself! "* The new American planes were a bitter disappointment, particularly their much-touted Liberty motor, which was re- placing the British Rolis-Royce. The ship was entirely clis- qualified from aerial combat. Webster has written about these trials: * Personal journal of David Locke Webster II.

DAVID LOCKE WEBSTER II 377 Then, what really made us boiling mad was to go back to quarters each evening and read in the newspapers that the Liberty motor was doing wonderful work over the lines in France, and that the British and French generals were congratulating our generals on these glorious airplanes- when we had the only ones in the world, all six of them, on our hands, more than 6,000 miles from the lines in France. We were too unsophisticated. We should have known that the first casualty in any war is God's truth.* In spite of these unwelcome finclings, Webster stayer! with the First World War until Armistice as lieutenant and as captain in the air service of the Army. Nearly all of his work was at Langley FielcI, Virginia. He remained in the air re- serves until 1924. TO STANFORD UNIVERSITY With the first war behind him, Webster returned to Michi- gan but within the year accepted an assistant professorship at Massachusetts Institute of Technology. After a single year at MIT, which at the time was just what the name says, Webster glaclly accepted from Stanford University an offer of full professorial status and Physics Department chairmanship. In 1920 Stanford was well known for its unique history and its supposed financial security, but its academic greatness was spotty. Physics was represented by a small, aging faculty, busy at their teaching anc! little involvecI in the twentieth century explosion of their discipline. In the Webster appointment Stanford hacI a young man (thirty-one) of unquestioned keenness, freshly developed in a center of eager scientific progress. His interests, his talents, and his experience showed a seemly balance of instruction, research, and academic citizenship. I, the writer of this account, then a graduate student at Berkeley across the Bay, met the new Stanford hope at interclepartmental physics conferences and recog- nized the awakening influence. *Ibid.

378 BIOGRAPHICAL MEMOIRS STANFORD PROBLEMS AND EVENTS In taking up the Stanford professorship (which was to run for thirty-four years) Webster was serving an academic em- oloYer Younger than himself and smaller (2,949 students) A--,-- ,~ than those he had known. The waiting tasks were as large ant] demancling as such things can be anywhere ant! left little time to grieve about the lack of a plane or a yacht. There was an atmosphere of good will all arouncl, and his acquaintance with physical sciences other than his own gained the respect of neighboring departments. He had great freedom of action ant! all the facilities therefor except money. The Bible almost says that the lack of money is the root of all evil. Among pre-WorId War IT experimental scientists this version had many believers. One of the things that President Wilbur hoped of Webster was that he might make Physics a significant research clepart- ment. Webster's own ability in this fielcI seems to have been evident to his Army and academic associates anti he had documented it by some fifteen published papers, but his name was not yet highly visible generally. Now it was not only his wish but also his cluty to build a creative investigative center at Stanford. Webster has told that in planning for research he scoured the University junkyards to pick up the material that might be converted into instruments for scien- tific observation and measurement. The construction was often clone by the scientist himself with the help of graduate students glad of a chance to earn twenty-five cents an hour. The problem here was to find the twenty-five cents, for there was no research budget as such. Professors necessarily did things almost incredible to their present-clay counterparts. In Webster's first Stanford re- search, he became carpenter, plumber, lineman, pump cleaner, ant! freight heaver as occasion required. Fortunately his chief collaborator, Professor P. A. Ross, was well enclowecl

DAVID LOCKE WEBSTER II 379 with extra-professorial talents. He was the only glass blower on the Quad, hac! made telescope mirrors, operated all the then-known machine tools, and liked to make them do tricks beyond the intentions of their designers. On surveying the instruction going on in his new Depart- ment, Webster found it lacking. Students were getting practically no chance to learn about what physicists were call- ing modern physics, not merely because their teachers were not close followers of twentieth century clevelopments but also because available textbooks were not telling the modern story. Furthermore, Webster criticized the general physics texts then available as being catalogs of facts worth knowing, rather than training manuals for finding out. So, working with Professor H. W. Farwell of Columbia University and Professor E. R. Drew of Stanford, he pro- cluced a new textbook entitled General Physics for Colleges in 1923. It was the first in America to give extended and con- nected treatment to the modern physics, and as such it was valued and adopted. But the insistence on thinking things through, albeit nonmathematically, though popular with the kind of students that elect physics, dismayed that greater number who took physics because they had to and who were used to getting grades by memory rather than by under- stancling. Books that try to comprehend a rapidly growing field go promptly out of (late, and this was perhaps the worst time to clo the definitive summary of modern physics. General Physics came out in 1923, the year in which Compton confirmed that light comes in particles and Pauli clarified atomic structures with his exclusion principle. In the next year, de Broglie suggested that particles are waves and the arrangements of electrons within atoms became clear. In the year after that, wave mechanics was born. So, in 1926 the second (anct last) edition of General Physics for Colleges was brought out, and while the ink was drying the wave nature of all matter was

380 BIOGRAPHICAL MEMOIRS proposed and convincingly defended, and Davisson and Germer were experimentally substantiating it for the impor- tant case of electrons. In the very next year, Heisenberg declared for uncertainty, shaking the foundations of general philosophies and putting a new one under physics. THE TEACHING PHYSICIST As a teaching physicist, Webster worked from a philoso- phy that has already been indicated. Students must not be allowed to think of physics as an esoteric mystery but rather as a means of understanding the why of what goes on around them and, progressively, of gaining explanations—even quantitative ones—of other phenomena far less commonly observed but pregnant with thrilling implications. Sometimes many questions may be grouped under a similar answer, from which emerges a "law." But in referring problems to laws the teacher must be careful to show that the law is a compact summarizing statement of human observations and not, in itself, a proper object of worship. Webster knew that laws are an enormous convenience, but when he introduced students to Boyle's law or Ohm's law or one of Newton's he was careful not to claim that the usual simple forms were absolutely and in all circumstances correct. in his book the three-letter statement of Ohm's law was carefully hedged with conditions about constancy of temperature, homoge- neity, and ambient magnetism. This extreme care about correctness was not found ingratiating by all students. Some teachers can stand up before an advanced class and say, "What ~ told you last year wasn't quite true." Such methods were not for Webster, and the inquiring and well-motivated minds commended his rigor. The above might suggest that Webster's lecture style was stiff or pedantically formal. On the contrary, it was conver- sational, without the meaningless sounds and ungrammatical shortcuts often condoned in such communication. As to the

DAVID LOCKE WEBSTER II 381 Webster textbook, users agreed that it was extremely hard to find errors in it, even in the first edition. This writer, an avid critic, never succeeded in finding even one. Webster was one of a group of physicists of standing who felt that teachers of physics, particularly at college levels, were such accidentally and were often lacking in special train- ing and in opportunities to secure such. Since the American Physical Society did not regard teachers as physicists and elected to ignore their problems, a group including Webster founded the American Association of Physics Teachers in 1930 and solicited a membership that has since built up to nearly ten thousand. He was active in this important organi- zation and in the years 1935 and 1936 served as its president. At Stanford Webster was employed to be both a teacher and an active researcher in the science of physics, and though he was fond of both activities and performed them expertly, he never recognized any helpful symbiotic relationship be- tween them. In 1957 he wrote: Speaking from my own experience, I have found that I could never make really good progress in any research job unless I neglected my under- graduate teaching, letting it coast along with obviously insufficient motive power. Conversely, I could never do much to improve any undergraduate course unless I let the moth and rust have their way with my research apparatus.* RESEARCH IN X-RAY PHYSICS Webster's productive researches may be considerecl in a few separable categories of which the first has to do with X-rays. His pioneer X-ray spectrometer observations have already been cited, and his Bibliography mentions a few other X-ray publications traceable to his brief terms at Har- vard, Michigan, anc! Massachusetts Institute of Technology. *Ibid.

382 BIOGRAPHICAL MEMOIRS But ideas developed faster than the possible testing of them, so he carried many of them to California for consideration in the research laboratory he was expected to develop at Stanford. His personal research efforts on the new job were largely devoted to observation of the bombardment of metallic atoms with electrons and the measurement of the resulting charac- teristic radiations. If this sounds like a puerile occupation, the reader—even the scientific one may pardon some amplif- cation. The real purpose of the experiment was to draw out internal information about the atom, that is, about any one of the atoms in a pure sample, let us say, of gold. The collision of an electron with an atom might energize the atom, causing it to emit a photon (radiation quantum) of a wavelength pecu- liar to its species. It was part of the investigator's task to catch and count the special photons, and in Webster's work they were always X-rays. The italicized uncertainty above was necessary because the chance of a productive collision is strongly dependent upon the energy of the bombarding elec- tron. For slow electrons the chance is zero, but with increas- ing speed that probability abruptly takes on a positive value, and this critical speed or energy is an important datum for the atomic theorist, who is also deeply concerned about how the probability varies with electron energy as bombardment speeds are pushed up. This dip into atomic science will still leave the lay reader dubious about the usefulness of the early Stanford X-ray in- vestigations, really atomic mechanics investigations in which X-rays were a by-product and a handle. The work was never understood by journalists or by the wives of physicists. Over the perspective of years, one may wonder that it ever suc- ceede(1 in an era when the directing scientist designed and built his own power supply, cleaned and serviced his own vacuum pumps, and measured his high voltages and his milk-micro signal currents with homemade meters. (For a

DAVID LOCKE WEBSTER II 383 fuller acquaintance with those times, see the Webster Bibliography. ) A more glamorous kind of X-ray research enlivened the Stanford laboratory when Webster and Professor P. A. Ross, about 1925, stepped into the controversial territory of the Compton effect, with clarifying effectiveness. As a point of information, the Stanford word klystron, now heard in all the principal languages, was coinecI or appro- priatecI after a visit by physicists to the Department of CIassi- cal Languages. In ancient Greek it meant something about sea waves, but in the modern definition it has to do with waves of electrons, a klystron being specifically a vacuum tube without a grit] but able to control such flow in an acivan- tageous manner utterly new to the world of 1937. Webster did little or none of the inventing but he understood more fundamentally than dicI its inventor and played a valuable role by elucidating its theory (see Bibliography) and by guicl- ing the poverty-stricken Department through a new phase of contact with University administrators and the extramural world of big industry and manufacture. He lived to see the new Plea built! buildings for his Department and start its growth to conspicuous world visibility. WORLD WAR I I Even before Pear! Harbor the war was molding that De- partment. Foresighted staff members were weighing choices of battle stations for what would be called a physicist's war. Klystron men were at war work already: the development of the tube hacT been prompted from the beginning by con- cern for civilian populations under bomber attack and lack- ing microwave power for effective radar. Parenthetically we may say here that klystron design, testing, and production clid get there on time to play a significant, and perhaps deter- minative, role in the Battle of Britain anti other engagements. Webster headed the klystron clevelopment until its size,

384 . BIOGRAPHICAL MEMOIRS commercial commitments, and internally competitive ambi- tions macle it obviously not at home as a subdivision of the small Physics Department. Klystron activity went to Long l[slancl with Sperry Gyroscope Company. To Webster, feel up with klystrons, the Pear! Harbor blitz was timely. His first comment on it was, "Thank Goct we are in the War before the enemy has hacT time to destroy all our friends!"* A few clays later, he struck out in search of a fitting wartime station. Too old for flying, he considerecI a few thinking posts and settled into duties as assistant chief of the Army Rocket Research Branch at Aberdeen Proving Grounds in Maryland, ant! here he served out the cluration. Webster later wrote, "I didn't know anything about rockets, but nobody in America knew much about them; so it was easy to get right up with the best of them."! At that time, the Germans clicI know much about rockets particularly large ones, ancI Aberdeen was developing the bazooka, a tactical weapon carried on the marksman's shoulder; a useful achievement of Webster's group was insuring that this weapon wouIcI dispatch its rocket forward instead of sideways into the soldier's heart. In the autumn of 1944, Webster was sent to EnglancI and France to judge the relative merits of different rockets. Though a civilian, he went dressed in the costume of a colo- nel, carrying a card stating that he hacI the rank of "assimi- lated" colonel, and furnished with decorations appropriate to that rank to pin on if taken prisoner. At such a point, he would be assimilated into the Army without gambit, a kind of plug for better accommodations for captains. His rocket study began in England and later took him to France ant! war zones, returning him to Aberdeen for separation in the summer of 1945. * Ibid. ~ Ibid.

DAVID LOCKE WEBSTER II WRITI N G TASKS 385 The Webster Bibliography, a part of this memoir, might stand by itself, but a few exceptional items merit individual comment. The International Craticat Tables was an eight- volume world first as a reference source on the physical properties of all sorts of substances. Spectrum lines were inclucled in its wide coverage, and Webster lecT the group who clip the X-ray spectra. He more or less justified this valuecl job of dull scholarship by pointing out that in the poverty year of 1929 it required no apparatus or other expense to Stanford. His airflight competence and enthusiasm tract survived World War I, and he had taught classes in "Air Craft Opera- tion" for the Civil Pilot Training Program of the Federal Civil Aeronautics Administration and hac! come to realize pain- fully that fliers were still being taught World War ~ super- stitions about the physics of flight and how to cope with its vital problems. Flight training had been cleansed of some of its plain denials of Newton's laws of motion, but not enough in Webster's view, since very few flight instructors had learned to read differential equations of the fourth order, while every airplane unclerstanc3s anal promptly obeys two such equations. Webster bought a 65-horsepower Cub, flew it from California to Washington (more specifically, to College Park, Maryland), and explained that he was the man who conic! revise their training literature so that it would neither make the trainee dizzy nor the scientist sick. He got the paying job promptly, along with the collaboration of junior authors, and spent the summer of 1940 happily rewriting and flying. Having been openly critical of some common textbook treatments of electric and magnetic theory, Webster was a natural candidate for membership in American Association of Physics Teachers' committees for review and recommen-

386 BIOGRAPHICAL MEMOIRS ciation in these fields. It may seem odcI that in the twentieth century physics teachers could not all immediately agree upon what shouIct be saicl about magnets ant! about electro- statically charged objects, these being matters that have been thought about for millennia. Here questions about experi- mental truth or mathematical rigor were few and readily answered; but matters of taste, philosophy, historical prece- clent, and even a little respect for tradition and authority arose to demonstrate that scientists are still humans. The Coulomb's Law Committee report was published in 1950, after two extender] summer meetings of committee work. Webster, as human as any, cticI a great part of the writing and injected a point of view that seems more and more natural and acceptable with the passing years. If a reader really wants to know what the preceding para- graph has been about, he may well turn to the Encyclopaedia Britannica of 1970 and react or browse Webster's fifty-seven- page general article "Electricity," a masterful presentation of a mathematical subject including general relativistic touches without mathematics beyond a little high-school reckoning. RETIREMENT AND THEREAFTER His postwar years at Stanford were not Webster's hap- piest. He has written that upon his return from the war he found himself a misfit at the University. The new University president had replacer! him as department executive. His old research quarters had been revised out of recognition and were now occupied by busy younger men with younger prob- lems. He said himself that nuclear research was a young man's game and he had voluntarily written himself out of the klystron empire, even to turning clown a piece of the ex- pectec! royalties. Ever concerned about the professor's dilemma of serving two masters, Webster now turned from research to teaching

DAVID LOCKE WEBSTER II 387 and accepted the assignment of putting in orcler the deplor- able engineering anc! science physics instructional program, which had slipper! too much into the hands of unregulated teaching assistants. In this useful job he made himself quite a student reputation. More widely distributes! benefit to phy- sics came out of his leacling role in the Coulomb's Law Com- mittee cliscussec! earlier. Following his retirement in 1954, Webster issued a dozen publications of scatterer! character, including several on rela- tivity matters and some ventures in astrophysics, which were facilitated by a congenial appointment at Ames Research Center, Moffett FielcI, California, with practically profes- sorial freedom to pursue mathematical research in space sciences. This was a clean slate. Years earlier he tract decried the attempts of aging scholars to ignore Nature's coo} insis- tence that they were not permanently productive supermen. He was going to recognize his mental deterioration before other people die! and go sail his boat. Now was the time to test such intentions, but the opportunity of an Inctian-summer career with old pressures off brought him into a more attrac- tive course ant! somehow a still productive one. Big modern research organizations, rapidly assembled, are staffer! with smart, young, cleeply specialized people, who have not taken the time to become broactly educated, even within science. A genial old man who knew so much about so much was a naturally popular consultant, both socially and profession- ally, in such company. SAILING AND FLYING Webster's life includes] the aIreacly mentioner! avocational enthusiasms of sailing and flying. The sailing interest was nothing new in the family; his Briggs maternal ancestors hac] been builders and sailors of Massachusetts ships for two cen- turies, up to about the Civil War times. The most celebrated

388 BIOGRAPHICAL MEMOIRS of these, the 220-ton Clipper ship Columbia, was the first American vessel to clouble stormy Cape Horn and ply the West Coast waters. She tracled in the American Northwest, where she gave her name to a great river, continuing west- ward thereafter ant! carrying the flag of the United States around the worm for the first time. Among the Briggs sailing men was a pirate, still spoken of in the family as Uncle Tom. It is recorded of this cousin of Webster's maternal grandfather that he was in and out of English prisons, bearing his fate calmly as a godly man may. When Webster was ten he and his brother were given a skiff with which they taught themselves to salt by doing it. He later explained that he surpassed preteen playmates in per- fecting this art because at that period he ctidn't give a clamn whether he drownecT or not. As life took on value, his aquatic instruction continued and he passed the grammar school of seamanship, which was Massachusetts Bay, and the high school, which was Cape Cocl. In the Webster literature are the names of eight winct- borne boats that he owned in whole or in part during his sailing life, and in one of which he anct two companions accomplished a round-trip cruise of 2,500 miles, circum- navigating New England, most of Nova Scotia, and slices of New York and Quebec. The closeness of sailing to his heart appears even in the choice of his first wife, Anna. The only real disappointment about the family move to California was the discovery that the state offered no good cruising for small sailboats. Webster searched and found nothing to meet his Atlantic standards within eight hundred miles, but British Columbia held the family's desires and there they spent several consecutive summers. Webster was interested in aviation before Kitty Hawk. He wrote, "I always wanted to get up in the air."* Boyhood para- *Ib~.

DAVID LOCKE WEBSTER II 389 chute jumps with a big umbrella enclec! in crash landings and he remained grounder] until WorIc! War I, though in the Harvard period he took part in the building of a plane that declined to fly. He has written that World War I gave him an excellent excuse for going aloft and he remembered: throughout life the elation of his first solo flight and his half-thinking, half-saying, "My God, here I am at last! Really flying and in full control! " ~ After military flying his circumstances grounc;led him for several years, but in the ~ 930's he was getting nostalgic for the air and took steps. Although a military pilot, experience(1 in the flying of thirteen plane types of the period, he took his first private pilot's license in 1936 (at the age of fifty-four) and celebratecl it by flying un(ler the Golden Gate Bridge. He later acknowledged that that was a dangerous sport in that he might have lost his license for it. With the talents of a natural seat-of-the-pants flier, Web- ster brought to the craft his mechanics, mathematics, meteor- ology, and love of nature. Flying became a fine family activity. Though Anna still preferred boats, his two sons were soon goof! fliers, relishing the air and fincling careers in it. One became a pilot with a commercial airline and the other server! as fighter pilot of the U.S. Airforce in World War IT. Webster owned five successively more powerful planes. The logbook of one of them came to show at least one landing in each of the forty-eight United States of the time. IN CONCLUSION The two strong egos of David ant! Anna Webster attracted like magnets for a few clecades, but a polarity reversal came ant! brought divorce in 1951. He soon marries! Olive Ross, a longtime widow of his early X-ray colleague, P. A. Ross. In the nine successful years of this marriage (unti! Olive's death) *Ibid.

390 BIOGRAPHICAL MEMOIRS she rendered him an abundance of human unclerstancting, literary criticism, social guidance, and flight companionship. The dearest friend of his later years was the space scientist, Alberta Alksne, with whom he wrote theoretical papers and toured Australia, New ZealancI, and the Barrier Reef. Webster stopper! working at NASA in 1975, when he was eighty-six years oIcI. He was not eager to quit, but years of battling with uremic poisoning had worn him clown ant! he cliect on December 17, 1976. He retained his curiosity about the worIct anc! life to the end, asking, almost at the last, "What's it all about?" It is not the function of these pages to praise but to recall anc! commemorate. In summary, Davic! Webster in his thirties was known among physicists of his time as an X-ray man anc! more particularly as an experimenter rather than as a theorist. This trend of his reputation was an acciclental result of his opportunities ant! no real choice of his own. He was conscious that he tract no great gifts of digital dexterity and no kind of apprenticeship in the manual arts of the instrument shop, but at Stanford, in a delicate anti budgetIess experimental program, any such disadvantages were com- pensatect by his superior understancling of what was being attempted, his mathematical familiarity with its past ant! pre- sumable future, and his ability to theorize his way out of a dilemma. In the twenties he was the only possible theorist in the small Department. He came to realize, though none too rapidly, that high-cIass power in such physics was an essential condition for the future growth ant! service of a university physics department in either its teaching or its investigative function. In this need he took the strong step of securing the appointment of Felix Bloch (1932), the more to Webster's crectit inasmuch as his makeup incluclect a trace of ethnic . . . . c .lscrlmlnatlon.

DAVID LOCKE WEBSTER II 391 This wouIcl have been an appropriate time to swing the research emphasis of the Department into one of the new productive channels, but Webster preferred to carry on with X-ray observations using more energetic collisions. This simple-sounding extension wouIct have required far bigger budgets than the Department tract ever seen; Webster went to the foundations for such support and was turned clown. This was his last attempt at major research leaclership. William Hansen, meanwhile, pores! over cheaper ways to get high- energy electron collisions producing the cavity oscillator, which lecl to the klystron and to the two-mile linear electron accelerator. In the list of Webster's life achievements the production of Hansen is not the least. This prodigious undergracluate (now long cleact) was first Webster's wor- shipper, then his replacement in advanced lectures, and later his adversary in klystron diplomacy and management. Webster held the fixed opinion that a university has in its work of teaching and scholarly investigation two separable functions with a degree of competition between them. He felt the dishonesty of spending tuition receipts on the showier activity of research, visible to clonors and popular with most of the costly scholars. Opposing this custom in principle, he unavoiclably practiced it and confessed in print that he could not serve two competing masters with fairness if he had to clivide individual clays between them. It was a relief to him that he lived to see research supported in relative abundance from other sources. Webster never click set his evident capacities and less evident ambitions on any resolute pursuit of maximum professional visibility. He took up the questions of living as they acictressec! him. His always curious mince was intrigued by the problems of nature and he solved a few. More solu- tions wouic! have meant more glory, but sometimes it ap- peared that his payoff was more in the solving than in the

392 BIOGRAPHICAL MEMOIRS solution. It was characteristic that when he visitec! Hawaii and saw the destructive work of a "tidal wave," he busied himself for two years on tsunami research and determined the effects of certain idealizec! island forms upon the impacting sea waves. When he learner! of the anomalous magnetizations frozen into historic lava flows, it was not long before he was in conference with vuIcanologists about causes of the phe- nomena and their possible use in predicting eruptions. The impression of Webster's personality was one of strength anc! gentleness. He was often charming, though cer- tainly with no intent to charm. He hac! some biases ant! the grace to conceal them. Though not infallible in clearings with people, he was quite clevoicI of guile and was irritated by signs of it in others. Since successful diplomacy cannot operate without guile, his had its limits. His judgments of others were confident, but some found his condemnations exaggerated. In general, people likecl him warmly and remembered him lastingly. His concern for public opinion was slight and yet detectable. His memory became richly Fled with science items now rapidly becoming historic anct with details of personal ex- periences relevant to many continuing lives. It must always seem a definite human loss when such slowly built files are wiped out without a copy. David Webster was elected to the National Academy of Sciences in 1923.

DAVID LOCKE WEBSTER II B IB LIOGRAPHY 1912 393 On an electromagnetic theory of gravitation. Proc. Am. Acad. Arts Sci., 47:559-81. On the existence and properties of the ether. Proc. Am. Acad. Arts Sci., 48:509-27. 1913 The theory of the scattering of Rontgen radiation. Philos. Mag., 25:23~1 '11. 1914 The effect of pressure on the absorption of light by bromine and chlorine, and its theoretical significance. Phys. Rev., 4:177-94. 1915 Planck's radiation formula and the classical electrodynamics. Proc. Am. Acad. Arts Sci., 50:129~5. The intensities of X-ray spectra. Phys. Rev., 5:238~3. The X-ray spectrum of tungsten at a constant potential. Phys. Rev., 6:56. Parson's magneton theory of atomic structure. Phys. Rev., 6:54. 1916 The emission quanta of characteristic X-rays. Phys. Rev., 7:403. The emission quanta of characteristic X-rays. Proc. Natl. Acad. Sci. USA, 2:90-94. Experiments on the emission quanta of characteristic X-rays. Phys. Rev., 7:599~13. With H. Clark. A test for X-ray refraction made with monochroma- tic rays. Phys. Rev., 8:528-53. Notes on Page's theory of heat radiation. Phys. Rev., 8:66-69. 1917 With H. Clark. The intensities of X-rays of the L series. Proc. Natl. Acad. Sci. USA, 3:181-85. X-ray emissivity as a function of cathode potential. Phys. Rev 9:220-25. .,

394 BIOGRAPHICAL MEMOIRS The theory of electromagnetic mass of the Parson magneton and other non-spherical systems. Phys. Rev., 9:484-99. Equations as statements about things. Science, 46:187-89. 1918 The scattering of alpha rays as evidence on the Parson magneton hypothesis. I. Am. Chem. Soc., 40:375-79. 1919 An approximate law of energy distribution in the general X-ray spectrum. Proc. Natl. Acad. Sci. USA, 5:163-66. The origin of the general radiation spectrum of X-rays. Phys. Rev., 13:303-5. 1920 The intensities of X-rays of the L series. II. The critical potentials of the platinum lines. Proc. Natl. Acad. Sci. USA, 6:26-35. The physics of flight. I. Franklin Inst., 189:553-80. Quantum emission phenomena in radiation. Phys. Rev., 16:31-40. Quantum emission phenomena radiation. Science, 51:504. Problems of X-ray emission. Bull. Natl. Res. Council U.S., 1: 427-55. 1921 High-frequency limits of X-ray spectra at different angles from the cathode stream. Phys. Rev., 18:155. Some X-ray isochromats. Phys. Rev., 18:321-22. A general survey of the present status of the atomic structure prob- lem. Bull. Natl. Res. Council U.S., 2:336-55. The present conception of atomic structure. Bull. Natl. Res. Coun- cil U.S., 2 (part 1):335-55. 1922 With H. N. Russell. Note on the masses of the stars. Not. R. Astron. Soc.,82:181-82. The penetration of cathode rays in molybdenum, and its effect on the X-ray spectrum. Phys. Rev., 19:545~6. A device for timing ionization currents accurately. Phys. Rev., 19: 546.

DAVID LOCKE WEBSTER II 395 1923 With A. E. Hennings. The penetration of cathode rays in molyb- denum. Phys. Rev., 21:301-11. With A. E. Hennings. X-ray isochromats of molybdenum. Phys. Rev., 21:312-25. With E. R. Drew and H. W. Farwell. General Physicsfor Colleges. New York: D. Appleton-Century Co. 1924 The distribution of energy in the continuous X-ray spectrum. Radi- ology, 2:21~21. A possible explanation of tertiary line spectra in X-rays. Proc. Natl. Acad. Sci. USA, 10:186-90. A possible explanation of tertiary line spectra in X-rays. Phys. Rev., 23:663. 1925 With P. A. Ross. The Compton effect with no box around the tubes. Proc. Natl. Acad. Sci. USA, 11:56-61. With P. A. Ross. The Compton effect: Evidence on its relation to Duane's box effect. Proc. Natl. Acad. Sci. USA, 11:61~4. With P. A. Ross. The Compton effect with hard X-rays. Tungsten K series. Proc. Natl. Acad. Sci. USA, 11:224~27. With P. A. Ross. The Compton effect with hard X-rays. Phys. Rev., 25:7 14. With P. A. Ross. The Compton and Duane effects. Phys. Rev., 25:235. 1926 The use of British units in the teaching of mechanics. Bull. Am. Phys. Soc., 1: 1-7. The teaching of physics, with special reference to the teaching of physics to students of agriculture. Bull. Am. Phys. Soc., 1:7-25. Continuity of the X-ray spectrum at a wave-length twice the short- wave limit. Phys. Rev., 27:638. 1927 Direct and indirect ejection of K electrons by cathode rays. Phys. Rev., 30:365.

396 BIOGRAPHICAL MEMOIRS Large losses of energy by cathode rays: Ratio of the probabilities of the two types. Phys. Rev., 30:365. Direct and indirect production of characteristic X-rays. Proc. Natl. Acad. Sci. USA, 13:445-56. 1928 Direct and indirect characteristic X-rays: Their ratio as a function of cathode-ray energy. Proc. Natl. Acad. Sci. USA, 14:330-39. K-electron ionization by direct impact of cathode rays. Proc. Natl. Acad. Sci. USA, 14:339-44. K-electron ionization by direct impact of cathode rays. Phys. Rev., 31:1118. With H. Clark, R. M. Yeatmen, and W. W. Hansen. Intensities of K-series X-rays from thin targets. Proc. Natl. Acad. Sci. USA, 14:679-86. With R. M. Yeatman. The ballistic method of ionization measure- ment with a quadrant electrometer. I. Opt. Soc. Am. Rev. Sci. Instrum., 17 :248-53. With R. M. Yeatman. Recombination of ions in the chamber of an X-ray spectrometer. Phys. Rev., 32:325. 1929 With W. W. Nicholas and M. Siegbahn. Emission of X-rays, wave- lengths and data on absorption limits. In: International Critical Tables, vol. 6, pp. 23-49. New York: McGraw-Hill. With W. W. Hansen. The relation between the continuous and line spectra of X-rays from thin targets. Phys. Rev., 33:635-36. 1931 With H. Clark and W. W. Hansen. Effects of cathode-ray diffusion on intensities in X-ray spectra. Phys. Rev., 37:115-35. 1932 With W. W. Hansen and F. B. Duveneck. Probabilities of K-electron ionization of silver by cathode rays. Phys. Rev., 42:141~2. With W. W. Hansen and F. B. Duveneck. Measurement of X-ray intensities as functions of voltage, up to 180 kv. Rev. Sci. Instrum., 3 :729~9.

DAVID LOCKE WEBSTER II 1933 397 With W. W. Hansen and F. B. Duveneck. Relative intensity of the silver K-lines from a thick target as a function of voltage and emergence angle. Phys. Rev., 43:385. With W. W. Hansen and F. B. Duveneck. Probabilities of K-electron ionization of silver by cathode rays. Phys. Rev., 43:839-58. With W. W. Hansen and F. B. Duveneck. X-ray line intensities and cathode-ray retardation in thick targets of silver. Phys. Rev., 44:25~64. With L. T. Pockman and P. Kirkpatrick. Probabilities of L ioniza- tions of Au by cathode rays. Phys. Rev., 44:130-31. 1934 Vacuum-leak hunting with carbon dioxide. Rev. Sci. Instrum., 5:42~3. Facing reality in the teaching of magnetism. Am. Phys. Teach., 2:7-10. Current progress in X-ray physics. Science, 79:191-97. Unscrambling the dielectric constant. Am. Phys. Teach., 2:149-51. On the teaching of magnetism. Am. Phys. Teach., 2: 179-80. With L. T. Pockman and P. Kirkpatrick. X-ray line intensities in thick targets of nickel. Phys. Rev., 45:151. 1935 With W. W. Hansen and F. B. Duveneck. Errata: Ionization area of He and Bethe's theory. Phys. Rev., 47:699. With W. W. Hansen and P. Kirkpatrick. Electron optics of a 3000 kv X-ray tube. Phys. Rev., 48:486. 1936 With W. W. Hansen. Electrostatic focusing at relativistic speeds. Rev. Sci. Instrum., 7:17-23. 1938 Contributions of Edwin Herbert Hall to the teaching of physics. Am. Phys. Teach., 6: 1~16. With N. C. Little, F. W. Warburton, M. W. White, S. R. Williams,

398 BIOGRAPHICAL MEMOIRS and W. H. Michener. What is the meter-kilogram-second system of units? Am. Phys. Teach., 6:144-51. 1939 Cathode-ray bunching. J. Appl. Phys., 10:501-9. Surface currents in deep tidal waters. Science, 90:107-8. The theory of klystron oscillations. I Appl. Phys., 10: 86~72. With L. T. Pockman, K. Harworth, and P. Kirkpatrick. Probability of K ionization of nickel by cathode rays. Phys. Rev., 55:682. 1 940 The ground school of the Civilian Pilot Training Program. Air Facts, 3: 16-27. Perceptual disorientation during landing of airplane. Science, 92:1-3. 1941 With L. T. Pockman. New techniques for making thin targets. Rev. Sci. Instrum., 12:389-92. With D. i. Brimm, Jr., and }. R. Cram. Flight Instructor's Manual, Civil Aeronautics Bull. no. 5, 3d ed. Civil Aeronautics Admini- stration. 146 pp. Wash., D.C.: U.S. Govt. Print. Off. With D. I. Brimm, fir., and I. R. Cram. Civil Pilot Training Manual, Civil Aeronautics Bull. no.23,2d ed. Civil Aeronautics Admini- stration. 334 pp. Wash., D.C.: U.S. Govt. Print. Off. 1942 Velocity modulation currents. J. Appl. Phys., 13: 786-87. 1946 Forces on ferromagnets through which electrons are moving. Am. J. Phys., 14:360-64. Forces on ferromagnets through which electrons are moving. Phys. Rev., 70:446. 1947 With L. T. Pockman, P. Kirkpatrick, and K. Harworth. The prob- ability of K ionization of nickel by electrons as a function of their energy. Phys. Rev., 71:330-38.

DAVID LOCKE WEBSTER II 399 With L. T. Pockman, P. Kirkpatrick, and K. Harworth. Probability of K ionization of nickel by electrons. Phys. Rev., 71:470. What shall we say about airplanes? Am. l. Phys., 15:228-37. 1950 With W. F. Brown, Jr., N. H. Frank, W. H. Michener, C. C. Mur- dock, and E. C. Kemble. The teaching of electricity and mag- netism at college level. Am. l. Phys., 18:1-25; 69-88. 1951 Masses of carriers in conductors. Phys. Rev., 82:808-9. 1953 Roentgen ray physics. In: The Science of Radiology, ed. Otto Glaser, pp. 39-63. Springfield, Ill.: Charles C Thomas. 1957 Reminiscences of the early years of the Association. Am. I. Phys., 25: 131-34. 1961 Relativity and parallel wires. Am. }. Phys., 29:841~4. Relativity of moving circuits and magnets. Am. I. Phys., 29:262-68. 1963 Schisms charges and currents in rotating matter. Am. I. Phys., 31:590-97. 1967 Dynamical friction. Am. }. Phys., 35:186-93. 1970 Electricity. In: Encyclopaedia Britannica, pp. 127-86. Chicago: En- cyclopaedia Britannica. With A. Y. Alksne. Magnetic and electric fields in the magneto- sheath. Planet. Space Sci., 18: 1203-12.

400 BIOGRAPHICAL MEMOIRS 1972 With A. Y. Alksne and R. C. Whitten. Does Io's ionosphere in- fluence Jupiter's radio bursts? Astrophys. }., 174:685-96. 1973 With R. C. Whitten. Which electromagnetic equations apply in rotating coordinates? Astrophys. Space Sci., 24:323-33.

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Biographic Memoirs: Volume 53 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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