Ernest Howard Griffiths. 15

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2 Ernest Howard Griffiths. 15 ERNEST HOWARD GRIFFITHS The triumphs of recent physical science have been so great, and have so filled our minds, that the work of those who completed the scheme of physics characteristic of the nineteenth century is in danger of being forgotten or, at best, regarded merely from the historical point of view. Forty years ago, it seemed that the main outlines of physics had been laid down once for a ll; it remained merely to carry the accuracy of physical measurements to another place of decimals, and devise a convincing electro-mechanical structure for the luminiferous aether. Yet, from nineteenth-century physics, those of the twentieth arose. The methods of the one enabled pioneers to reach the new fields of the other, and the older mechanical theories of matter and energy led naturally to the wider, if vaguer, concepts of to-day. Even the road by which the new fields were approached, the discharge of electricity through gases, was traced by means of that concept of ions developed in the older theory of liquid electrolysis. This sketch may help to make clear the place of Griffiths in the history of science. He was not a pioneer in physical theory, but, accepting the ideas of his age, he used his remarkable experimental skill, and his insight into what was worth doing, to investigate the possibilities of laboratory apparatus, and then to obtain the highest attainable accuracy in the measurements of really important physical constants. Although some of his later determinations were useful as a test of the quantum theory, his real work was done in helping to finish the structure of nineteenth-century physics. Ernest Howard Griffiths was born on June 15,1851, at Brecknock, where his father, the Reverend Henry Griffiths, was principal of the Memorial College. By his mother he was descended from Admiral Blake. At Owens College, Manchester, he won a Whitworth Scholarship, and then entered Sidney Sussex College, Cambridge, in Here, perhaps, for the first time, he found freedom to develop new sides of his character. The social side of university life appealed to him music, rowing, tandem-driving, and at a later period yachting, being apparently the most prominent of his many activities. Thus he gave pleasure to himself and to the growing number of his friends, and gained new accomplishments, not without educational value. He took an ordinary or pass degree by way of the Applied Science Special Examination in He soon put his knowledge of the Pass examinations to good account, becoming one of the most popular private tutors or coaches of his day. He and Dr. Campbell, a lawyer, joined forces, and in rooms over those of the Hawks Club conducted a very successful coaching establishment. Those who are familiar with the Previous Examination of those now far-off days will appreciate the understanding of the average Poll man s mentality which

3 16 Obituary Notices. Griffiths showed by his invention of Paley Pool as an incentive to the acquisition of knowledge. At a later date, in partnership with C. T. Heycock, he taught men for the First M.B. examination. It will be seen how far Griffiths was from the usual type of Cambridge Don. He once told me that it was a chance disparaging remark about Poll men made by one who, like most of his colleagues, had taken high academic honours, that led him to determine that he would show the Cambridge world that a Poll man could do good research work in the realm of pure science. The historic work of Joule on the dynamical measure of the thermal unit had been repeated by Rowland in But the advances in measurement of electrical quantities in the succeeding years, and the introduction of accurate standard cells for the control of voltage, made a new investigation by electrical methods both possible and desirable. It was this problem of getting the best results from electrical measurements that in 1887 Griffiths set himself to solve. The first preliminary was a study of thermometry, and in 1891 he published a paper on the Determination of some Boiling and Freezing Points by means of the Platinum Thermometer. * Callendar had given an empirical formula for temperatures measured on the platinum thermometer as compared with those on the gas thermometer. Griffiths found that the coefficient in the formula varied from wire to wire, so that to express platinum temperatures in terms of the gas thermometer, three fixed points were necessary. Callendar and Griffiths, working together, then made an accurate determination of the boiling point of sulphur.f To carry on his experiments on Joules equivalent J, Griffiths built a laboratory in the garden of his house, No. 12, Parkside, and here for the next ten years he spent the scanty leisure his arduous work as a coach allowed him amid a gradually increasing complexity of physical apparatus. The house was a pleasant meeting place for those who enjoyed the privilege of the friendship of Griffiths and his wife a daughter of Mr. G. D. Clark, of Bowden, Cheshire. They had no children; but were the centre of a charming circle, which contained such eminent men and such good fellows as C. T. Heycock and F. H. Neville. The first-fruits of these labours appeared in 1893$. The chief ideas underlying the experiments are shown in the full title of his paper The Value of the Mechanical Equivalent of Heat deduced from some experiments performed with the view of establishing the Relation between the Electric and Mechanical Units ; together with an Investigation into the capacity for Heat of Water at Different Temperatures. The precautions which Griffiths proved to be * Phil. Trans., A, vol. 182, p. 43 (1891). t Phil. Trans., A, vol. 182, p. 119 (1891). } Phil. Trans., A, vol. 184, p. 361 (1893).

4 Ernest Howard Griffiths. 17 necessary for this laborious investigation threw much light on the failure of previous observers to obtain consistent results. Using a temperature range of 14 to 26 C., he found a value for the calorie of 4*192 Joules, taking the electromotive force of the Clark cell to be volts, Rowland s result over the same range being 4*182. From this comparison, Griffiths prophesied that the next accurate measurement would reduce the accepted value for the Clark cell. Another paper followed on The Heat of Evaporation of Water. * In 1897 Griffiths turned to the accurate measurement of the freezing points of dilute aqueous solutions, constants of great importance in the thermodynamic and electrolytic theory of solutions. Preliminary announcementsf indicated that his results conformed accurately to theory, the molecular depression of the freezing point of potassium chloride being double that for cane-sugar within extraordinarily narrow limits of experimental error. But by this time Griffiths had left Cambridge, and he never completed the experiments in the way he had planned. His next activities were concerned with administrative work. In 1901 he was made Principal of the University College of South Wales and Monmouthshire at Cardiff, and also Professor of Experimental Philosophy. Three times he served as Vice-Chancellor of the University of Wales, and he was continuously occupied not only with the management of his College but also with local government. Moreover, he spent much time in spreading among the miners of South Wales a knowledge of the effects of science on industry. It was some years after his migration to Cardiff before a laboratory was built and equipped, and he was able to apply himself once more to exact physical measurement. In collaboration with Ezer Griffiths he investigated and published three papersj on the Capacity for Heat of Metals at Different Temperatures. Here, as in former work, electrical methods were used, and a very high order of accuracy reached, which led to a valuable comparison with the formulae derived by various physicists from modern quantum theories. Griffiths became a Fellow of the Royal Society in He was a Member of Council from 1909 to 1911 and in 1907 he was awarded the Hughes Medal for his researches. He was elected a Fellow of Sidney Sussex College in 1897, and at a later date he was made an Honorary Fellow. These distinctions he prized highly; his College was to him a second home. Griffiths always took a keen interest in the British Association in its lighter as well as its more serious activities. At the York Meeting in 1906, as President of Section A, he gave an admirable address on recent advances in physics, and at Birmingham in 1913 he presided over Section L, Education. In 1920 he was elected General * *Phil. Trans., A, vol. 186, p. 261 (1895). f *Rep. Brit. Ass., p. 477 (1906). *Phil. Trans., A, vol. 213, p. 119 (1914); vol. 214, p. 319 (1914); Proc. Roy. Soc., A, vol. 89, p. 561 (1914). OBIT. C

5 18 Obituary Notices. Treasurer, an office which he held till in such ways, as well as in his experimental labours, he did good service to science. In 1918 Griffiths retired from Cardiff and returned to Cambridge to live at No. 5, Selwyn Gardens. The death of his wife, which happened soon afterwards, deprived him of much of the pleasure the return should have given him, and, indeed, saddened his later years. This loss, and a gradually increasing rheumatic affliction, weighed on him heavily. But he faced his sorrows and disabilities with never failing and cheerful courage, working effectively till near the end. Griffiths was a man of many interests, grave and gay, a keen yachtsman, a skilled musician, a writer of merry songs, as well as an eminent experimental physicist and a great teacher and administrator. But to his many friends, his lovable character and sane and humorous outlook on life meant even more than his scientific achievements or his social activities. By those of them who survive him he will not be forgotten. W. C. D. D. ALBERT ABRAHAM MICHELSON Albert Abraham Michelson was born on December 19, 1852, at Strelno in Posen, now restored to Poland. When he was two years old, he was taken by his parents, Samuel Michelson and Rosalie (Przlubska), to the United States, and, after some fifteen years spent in Virgina City, Nevada, where his brother Charles was born, San Francisco became their home. There his sister Miriam, the author, was born, and the boy attended the high school. He was given, in unusual circumstances, an appointment in the U.S. Naval Academy at Annapolis, and after graduating in 1873 he became a midshipman in the U.S. Navy for two years and was afterwards appointed instructor in physics and chemistry in the Naval Academy in 1875, holding the appointment until His next year was spent in the Nautical Almanac Office in Washington, and then he studied for two years at the College of France, and at Heidelberg and Berlin. In 1882 he became Professor of Physics in the Case School of Applied Science at Cleveland, Ohio. After seven years he went as Professor of Physics to Clark University, Worcester, Mass., and remained there until He was then appointed Professor at the head of the Ryerson Physical Laboratory, Chicago ; this appointment he held until shortly before his death, which occurred on May 9, He married Miss Edna Stanton of Lake Forest, Illinois, in 1899, and they had a son and two daughters. This in brief contains the history of his official appointments : how he filled the various posts is another matter. He was an experimenter of great ingenuity.