EMINENT CHEMISTS OF OUR TIME $ m EMINENT! * OF EMI OJ BENJA1N|[N |lARR ? I ! OO M P oo 1 m li - o 11 1* 5 o 111! 1 a if H iffl? ou swili if |i * - IS 4 i! a . . 1= li , , | S; fe ' titi * i BH 1^ 13 %& so jj |- ? g || g- II 2 " S II 2 II ' ' rn H ' M i A r\ d a J3 (/) xn W r l > Wf I II II I ^^ ^j H^ O\ O H EMINENT CHEMISTS OF OUR TIME lithium, and so on. In other words, the elements in the vertical columns show striking similarities in proper- ties. Such is the gist of this law, though its details are much more complicated. What were its immediate results? To begin with, a number of the elements did not fit in with Mendeleeff's scheme. Forthwith Mendeleeff announced that the fault lay with incorrect atomic weights which had been assigned these elements. Mendeleeff proved right in all such cases. Thus, to take one example, the then accepted atomic weight for gold was 196.2 ; accordingly it should have been placed before such elements as platinum, iridium and osmium, with atomic weights of 196.7, 196.7 and 198.6 respec- tively. But Mendeleeff insisted upon putting gold after these elements, claiming that their atomic weights, and not his table needed revision. Subsequently, a revision of their atomic weights gave these results: Osmium 190.9, Iridium 193.1, Platinum 195.2 and Gold 197.2, which was precisely the order in which Mendeleefif had originally placed them. But Mendeleefif did something far more daring. The grouping according to Mendeleefif's scheme resulted in certain gaps being left unfilled. This, said Mendeleeff, was due to elements which awaited discovery. By a careful consideration of the properties of adjacent ele- ments the great Russian predicted the properties of these undiscovered elements. A case will be cited. To one of these unknown ele- ments Mendeleeff gave the name ekasilicon, and certain properties were predicted for it. In 1886 Winkler dis- covered germanium, which showed identical properties with this ekasilicon, as the following comparison will show: 28 DMITRI IVANOWITCH MENDELEEF Mendeleeff's Winkler's Ekasilicon Germanium Atomic weight Es, 72 Ge, 72.5 Density Es, 5.5 Ge, 5.469 Density of oxide EsO 2 , 4.7 GeO 2 , 4.703 Density of chloride EsCl 4 , 1.9 GeCl 4 , 1.887 f Less than 100 f 86 degrees Boding point of chloride. . A .. A -\ . I degrees centigrade I dentigrade Density of ethide Es(C 2 H 6 ) 4 , 0.96 Boiling point of ethide 160 160 These wonderful predictions did more to convince scientists of the validity of the law than anything else could have done. The soundness of a theory is best exemplified by the use to which it can be put. Does it explain anomalies? Does it guide along future paths of investigation? The Periodic Law has more than ful- filled these requirements. As a beacon it stands out as prominently hi the history of chemistry as does Dalton's Atomic Theory, which is at the very foundation of our science to-day. Some of the most startling dis- coveries of our time, such as the rare gases of the atmosphere (see Ramsay) and the radioelements (see Curie and Richards) are directly attributable to the Periodic Law. 2 The same year that saw the publication of Mendeleeff's immortal paper, that is, in 1869, als witnessed the pub- lication of his Principles of Chemistry, which in some 2 It should be mentioned that Chancourtois in France, and Lothar Meyer in Germany, also suggested periodic classification of the elements. Lothar Meyer, in particular, with his atomic volumes the volumes occupied by atomic weights of the elements was able to uncover some striking analogies. Lothar Meyer and Mendeleeff's papers were published in the same year 1869. The time unquestionably was ripe for some such formulation. In a similar way, Darwin and Wallace, ten years earlier, unfolded the origin of species quite independently of one another. 29 EMINENT CHEMISTS OF OUR TIME ways stands alone among chemical books. One of its unique features is the very elaborate footnotes in smaller print, which occupy more space than the actual text, and which are mainly taken up with the personal views of the author. These footnotes give the key to any number of new problems, and are the source of perennial inspiration to readers. The two volumes of the Principles have gone through many editions in many languages (including English), and its text seems little antiquated even to-day, which is an exceptionally high compliment to be paid a chemical work that has been before the public for fifty years. In the first chapter of volume II the reader will find an illuminating account of the author's Periodic Law. 3 Till his death, in 1907, Mendeleeff worked and wrote incessantly. He, together with his co-workers, pub- lished more than two hundred and fifty articles, touching every phase of chemistry. Indeed there is not a branch of our science but was enriched by his contributions. Abstruse subjects such as the properties of liquids, theories of solution and the development of the gas laws, seem but distantly connected with the pressing problems of the day, though they are not so far removed as the layman is apt to think. The constitution of the upper atmosphere, the aether, seems a metaphysical problem perhaps. But in addition to such profound investigations in chemical philosophy, Mendeleeff proved of much practical value to the government and the people of Russia by his exhaustive investigations of the Baku oil fields. Mendeleeff's first report on the naphtha springs in the Caucusus was issued as early as 1866. In 1876, in order to get further first-hand information, he visited 8 Though commonly known as the Periodic Law, the Periodic System is a much better name for it. 30 DMITRI IVANOWITCH MENDELEEF the Pennsylvania oil fields. The possible exhaustion of the Baku petroleum led the Russian Government to requisition his services in 1886. His suggestions led to fruitful results. In 1887, during a solar eclipse, Mendeleeff ascended alone in a balloon to make various scientific observations. This ascent was not without its perils, and gave some anxious moments to his assistants, but it had its reward in the local fame which it earned him; " for the peasant women thereafter used to tell that Dmitri Ivanovitsch flew on a bubble and pierced the sky, and for this the authorities made him a chemist! " In 1882 Mendeleeff and Lothar Meyer were awarded the Davy Medal of the Royal Society, the Copley Medal going to Arthur Cayley, the mathematician, and a Royal Medal, to the late Lord Rayleigh. " Like every great step in our knowledge of the order of nature," said the president, William Spottiswoode, " this periodic series not only enables us to see clearly much what we could not see before ; it also raises new difficulties, and points to many problems which need investigation. It is certainly a most important extension of the science of chemistry." Mendeleeff was chosen for the Copley Medallist, the Royal Society's highest award, in 1905. By this time he had reached the very zenith of his fame. " Men deleeff," said Sir William Huggins, "stands high among the great philosophical chemists of the last century." At various other times he was honored with degrees from Princeton, Oxford, Cambridge and Gottingen, and in 1889 he won the Faraday Medal of the English Chemical Society. These marks of recognition, gratifying as they were, could hardly compensate for the annoyances which 31 EMINENT CHEMISTS OF OUR TIME Mendeleeff experienced as professor at the university. Whether envious because of his reputation, or finding him unacceptable because he was not a well-defined autocrat, the Academy at Petrograd black-balled him. The Ministry of Education considered him far too much of a liberal, whereas many of the students were of the opinion that he never went far enough. He does not seem to have been particularly welcome hi either opposing camp. Occasionally, because of his neutrality, Mendeleeff attempted to act as mediator. On one of these occa- sions, hi 1890, after serious disturbances at the uni- versity by the students, resulting, as usual, from the ruthless suppression by the police of any semblance of freedom of thought, Mendeleeff partly pacified the under- graduates by promising to present their petition to the Minister of Education. This was enough to bring down the wrath of the official ministry upon him. In a very sharp note he was told to steer clear of aught but what concerned him as teacher of chemistry. Mendeleeff felt this sting so deeply that he resigned from his chair at the university. Some amends were made three years later when Sergius Witte, the Minister of Finance, appointed him Director of the Bureau of Weights and Measures a post he retained until his death. Those who have read his Principles can form some opinion of what a stimulating lecturer Mendeleeff must have been. We would have expected the author of the Periodic Law to have emphasised the co-ordinated links in the chain, and to have presented a unified picture of the whole subject of chemistry. Such, indeed, is the testimony of his students. Mr. I. Goldenberg writes: "I was a student in the Technological Insti- tute from 1867-9. Mendeleeff was our professor, and in 1868 taught organic chemistry. The previous course 32 DMITRI IVANOWITCH MENDELEEF by the professor of inorganic chemistry consisted of a collection of recipes, very hard to remember, but, thanks to Mendeleeff, I began to perceive that chemistry was really a science. " The most remarkable thing at his lectures was that the mind of his audience worked with his, forseeing the conclusions he might arrive at, and feeling happy when he did reach these conclusions. More than once he said, ' I do not wish to cram you with facts, but I want you to be able to read chemical treatises and other literature, to be able to analyse them, and, in fact, to understand chemistry. And you should remember that hypotheses are not theories.' " He was considered among the students a liberal man, and they thought of him as a comrade. More than once during a disturbance between the students and the administration Mendeleeff supported the students, and under his influence many matters were put right." Prince Peter Kropotkin, the well-known Russian socialist, was also one of Mendeleeff's students. " I had the good fortune," writes the Prince, " to follow, in 1867-9, his lectures on both organic and inorganic chemistry. The former was an abridged course, which he had the admirable idea to deliver for us students of the mathematical branch of the physico-mathematical faculty. "... Imagine each of these notes [referring to the footnotes in the Principles] developed into a beautiful improvisation, with all the freshness of thought of a man who, while he speaks, evolves all the arguments, for and against, there on the spot. " The hall was always crowded with something like two hundred students, many of whom, I am afraid, could not follow Mendeleeff, but for the few of us who could 4 33 EMINENT CHEMISTS OF OUR TIME it was a stimulant to the intellect and a lesson in sci- entific thinking which must have left deep traces in their development, as it did in mine." In 1863, two years after his appointment at the Tech- nological Institute, Mendeleeff married his first wife (nee Lesthoff). With her he had a son, Vladimir, who died in 1899 at the age of thirty four, and a daughter, Olga. This marriage proved an extremely unhappy one. For some time they lived apart, and finally they were divorced. In 1877 he fell in love with a young lady artist, Anna Ivanovna Popova, of Cossack origin, and the two were married in 1881. From his second wife Mendeleeff received his very decided views on art. These found characteristic ex- pression in a letter he wrote to the Russian daily, Goloss (the voice) on the subject of a picture by Kouindji, Night in the Ukraine: " Landscape was depicted in antiquity, but was not in favor in those days. Even the great masters of the sixteenth century made use of it merely as a frame to their pictures. It was the human form which inspired artists of that epoch; even the gods and the Almighty himself appeared to their minds in human shape. In this alone they found the infinite, the inspiring, the divine. And this was because they wor- shipped human mind and human spirit. " This found expression in science in an exceptional development of mathematical logic, metaphysics and politics. Later, however, men lost faith in the absolute and original power of human reason, and they discovered that the study of external nature assists even in the correct appreciation of the nature of the human inner self. Thus nature became an object of study; a natural science arose unknown either to antiquity or to the period of the Renaissance. 34 DMITRI IVANOWITCH MENDELEEF " Observation and experience, inductive reasoning, submission to the inevitable, soon gave rise to a new and more powerful, more productive method of seeking truth. It thus became evident that human nature, including its consciousness and reason, is merely a part of the whole, which is easier to comprehend as such from the study of external nature than of the inner man. External nature thus ceased to be subservient to man and became his equal, his friend. . . . Inductive and experimental science became a crown of knowledge, royal physics and mathematics had now to be content with modest questioning of nature. " Landscape painting was born simultaneously with the change, or perhaps a little earlier. Thus it will probably come to pass that our age will hereafter be known as the epoch of natural science in philosophy and of landscape hi art. Both derive their materials from sources external to man. . . . Man has, however, not been lost sight of as an object of study and of artistic creation, but he now appears, not as a potentate or as a microcosm, but merely as part of a complex whole." Mendeleeff 's wife adorned his study with pen sketches of such scientific celebrities as Lavoisier, Descartes, Newton, Galileo, Copernicus, Graham, Mitscherlich, Rose, Chevreul, Faraday, Berthelot, Dumas, etc. The family first lived at the university, then in a house specially built for the Director of the Bureau of Weights and Measures. In this house his children by his second wife were born: Lioubov (Aimee), Ivan (Jean), and the twins Maria and Vassili (Basile). In appearance Mendeleeff was a genuine Slav. Medium in height, rather powerfully set, with an abund- ance of hair reminding one of a Paderewski, expressive blue eyes, high cheek bones, an immense forehead, he commanded attention wherever he went. At home he 35 EMINENT CHEMISTS OF OUR TIME went about in loose garments of his own design, some- what after the fashion of his illustrious compatriot, Tolstoy. For all the pomp of court life, in fact, for any osten- tatious display, he had nothing but contempt. His presentation to Tsar Alexander III was made possible only by the permission which was given him to wear anything he pleased. This embraced non-interference with his proud locks. His democracy showed itself in peculiar ways. For example, he always insisted on travelling third class in his short journeys from Petrograd to his estate, but at the station his driver, Zassorin, was always at hand with the troika and a pair of magnificent greys, and the somewhat shabby third class traveller became suddenly transformed into the wealthy landowner. Mendeleeff was a Russian of the temperamental variety a quite common variety of Russian; he was rather hard to live with, at times smooth and silky in speech, at other times quite uncontrollable hi temper, and for no apparent reason. Though unconcerned as to his personal appearance, Mendeleeff was extremely sensitive as to the way people received him. He knew himself to be a genius, and he expected people to pay homage. In this con- nection Sir William Ramsay tells of an amusing incident which occurred at a dinner in London, given to W. H. Perkin in 1884: " Iwas very early at the dinner and was putting off time, looking at the names of people to be present, when a peculiar foreigner, every hair of whose head acted in independence of every other, came up bowing. I said, * We are to have a good attendance I think.' He said, * I do not spik English.' I said, ' Vielleicht sprechen Sie Deutch? ' He replied, ' Ja ein wenig. Ich bin MendeleenV I did not say, * Ich 36 DMITRI IVANOWITCH MENDELEEF bin Ramsay,' but ' Ich heisse Ramsay,' which was per- haps more modest. His method reminded me of * the only Jones.' Well, we had twenty minutes or so before anyone else turned up and we talked our mutual subject fairly out. He is a nice sort of a fellow, but his German is not perfect. He said he was raised hi East Siberia and knew no Russian even till he was seventeen years old. I suppose he is a Kalmuck, or one of these out- landish creatures." In 1900 the Prussian Academy celebrated its two- hundredth anniversary, and the University of Petrograd sent Mendeleeff as its delegate. At the banquet van't Hoff presided over one of the side tables, with Laden- burg (the Breslau representative) to the right, and Mendeleeff to the left of him. Mendeleeff was an inveterate smoker, and simply chafed because he could not eat and smoke alternately. Ladenburg tells us that immediately after the soup Mendeleeff began to pump those around him as to whether he could be allowed to smoke. They answered him that that was out of the question. But he repeated his question after the first, and after the second courses. Then dear old van't Hoff, who hated to see anyone suffer so, stepped hi with the risky suggestion that he also would join hi a smoke. And the two went to it, to the great relief of Mendeleeff, who from then on proved an enjoyable companion. But the sad side of the incident was that van't Hoff, who had begun to show incipient signs of tuberculosis, had been expressly forbidden smoking. The present outcry against the classics, and the belief by many in America and England that a portion of the classical scholarship of statesmen could well be dis- placed by scientific information, was echoed by Mende- leeff long before the World War emphasised the im- perative necessity of a utilitarian education. In 1901 37 EMINENT CHEMISTS OF OUR TIME he published a pamphlet on Remarks on Public Instruc- tion in Russia, in which there occurs the following: "The fundamental direction of Russian education should be living and real, not based on dead languages, grammatical rules, and dialectical discussions, which without experimental control, bring self-deceit, illusion, presumption, and selfishness." Universal peace and the brotherhood of nations, says Mendeleeff, with, we are afraid, a super-abundance of confidence in his view, can only be brought about by a vital realism in schools. " For such reforms are re- quired many strong realists; classicists are only fit to be landowners, capitalists, civil seiyants, men of letters, critics, describing and discussing, but helping only indirectly the cause of popular needs. We could live at the present day without a Plato, but a double number of Newtons is required to discover the secrets of nature, and to bring life into harmony with the laws of nature." From such remarks the reader may conclude that Mendeleeff was perilously near being a radical. As a matter of fact this is no nearer the truth than the infer- ence that because he used the third class railway com- partment he was to be considered one of the people. Mendeleeff, in fact, was regarded by many as a rigid monarchist. The Russo-Japanese War, for example, found him in the camp of the jingos. The revolutionary outbreaks during the war, and Russia's defeat, un- questionably hastened his end. Scientific Russia, which had bestirred itself to great undertakings in 1904 in honor of the Master's seventieth celebration, found itself little encouraged hi its proceedings by the broken spirit in Petrograd. When he was hi his library and wrote articles, Mende- leefif described himself as an " evolutionist of peacable type." 38 DMITRI IVANOWITCH MENDELEEF His attitude towards women was equally characteristic. To show his broad-mindedness, he employed some of them at the Bureau of Weights and Measures, and even lectured to them. But he did not hesitate to make clear that they were decidedly inferior to men in intellect. Feminists, he declared, perhaps with some truth, aimed not so much at equality of political position as at oppor- tunities for work, to escape inactivity. His day's work done, Mendeleeff would retire to his estate at Tuer, Boblova, and dine at six. Then he was very fond of company, and could be seen at his best. Mendeleeff at his best had hardly a peer, particularly when the subject turned to the philosophy of science. After dinner, if alone with his family, he would puff at his cigarette and usually read books of adventure Fenimore Cooper, Jules Verne and the like. Some- times, being really fond of literature, he would read deeper things. Among Russians, Maicofif and Tutt- cheff were his favorites; outside of his own country he loved Byron best. Byron, as we shall see, was also van't Hoff's literary hero. The theatre saw Mendeleeff seldom, but music was a favored form of recreation. In this field of art he had decided preference for Beethoven. " But of all things I love nothing more in life than to have my children around me ; " which brings us to the most lovable side of Mendeleeffs personality, and here we shall leave him. Mendeleeff died in 1907 from an attack of pneu- monia. Just prior to falling into an unconscious state, he had requested that Jules Verne's Journey to the North Pole be read to him. Tolstoy commands no more dominating position in literature than does Mendeleeff hi chemistry. Both belong to the world at large, and the world is thankful 39 EMINENT CHEMISTS OF OUR TIME to them and to Russia for having enriched the intellect of so many of us. References Some of the facts come from private sources. I have, however, drawn freely on Prof. Tilden's article (i). Prof. Walden's essay (2) also proved very useful. Sir Edward Thorpe's sketch (3) carries us up to 1889. MendeleefFs book (5) is well worth examination. Other references are 4, 6 and 7. 1. W. A. Tilden: MendelSeff Memorial Lecture. Journal of the Chemical Society (London), 95, 2007 (1908). 2. P. Walden: Dmitri Iwanowitsch Mendelejeff. Berichte der deutchen chemischen Gesellschaft (Berlin), 41, 4719 (1908). 3. Sir Edward Thorpe: Essays in Historical Chemistry (Macmillan and Co. 1911). 4. D. I. Mendeleeff: An Attempt Towards a Chemical Conception of the Ether (Longmans, Green and Co. 1904). 5. D. I. Mendeleeff : The Principles of Chemistry. 2 vols. (Long- mans, Green and Co. 1905.) 6. F. P. Venable: The Development of the Periodic Law (Chemical Publishing Company. 1896). 7. A. E. Garett: The Periodic Law (D. Appleton and Co. 1909). 40 WILLIAM RAMSAY |N that elegant tribute to Ramsay, written in the days when comradeship between the scientists of England and Germany was close, Ostwald summarizes him as one belonging to the romantic type in science. Romantic he was, for his imagination was unlimited. The secret of Ramsay's great triumphs lay in the fact that with this imagination there was a well-balanced knowledge of the science, with a seer's insight into the significance of its laws. Bold in the conception of a problem, he was brilliant beyond comparison hi its execution. With no fetish to hold him, with the mantle of the prophet about him, and with amazing manipulative skill, he layed bare, in rapid succession, a regular little battalion of new gases in the atmosphere, followed by transmutation experi- ments which made the scientific world gasp and hold its breath in expectancy of the next dare-devil leap. This genius, born in Glasgow in 1852, did not spring from any geniuses, but like many another man of talent, his stock was of a fairly ordinary type. To be sure, there was an uncle with a reputation as a geologist, and his own father had some scientific tastes, but nothing at all to warrant such outpourings in the offspring. When eleven years old he joined the Third Latin Class of the Glasgow Academy, and during the three succeeding years at the institution he did little Latin, gained no prizes, and did much dreaming. Ramsay describes himself in a short autobiography as "to a certain ex- tent precocious, though idle and dreamy youngster." This fits in with Ostwald's theory of the genius: " The 41 EMINENT CHEMISTS OF OUR TIME precpciousness is a practically universal phenomenon of incipient genius, and the dreamy quality indicates that original production of thought which lies at the basis of all creative activity." Even thus early he evinced a passion for languages, for it is recorded that during sermon time at church he read the French and German texts of the Bible and translated them into English. In after years, as president of an international scientific gathering, he would astound the assembly by addressing them successively in French, German and Italian. His introduction to chemistry came in quite an unex- pected way. A football skirmish resulted in his breaking a leg, and to lessen the monotony of convalescence, Ramsay read Graham's Chemistry, with the object, as he frankly confesses, of learning how to make fireworks. During the next four years his bedroom was full of bottles, and test tubes, and often full of strange odors and of startling noises. But systematic chemistry was not taken up till 1869, three years after he had entered the University of Glasgow. Then, it seems, the passion came on, and with it, a passion for the cognate science, physics. This resulted in an introduction to William Thompson (later Lord Kelvin), the professor, who set the youngster upon the elevating task of getting the " kinks " out of a bundle of copper wire, an operation which lasted a week. It is to be presumed that Thomp- son was favorably impressed with the manner in which this piece of research was carried out, for Ramsay was immediately introduced to a quadrant electrometer and asked to study its construction and use. A year's introductory study of chemistry decided Ramsay upon his career, and with his parents' blessing he set out for Heidelberg in 1870, to be exchanged for Tubingen some months later. In Tubingen ruled Fittig, whose lectures were " distinct and clear," 42 WILLIAM RAMSAY whose scholarship was sound, and whose research was methodical. The two years spent at Tubingen were full of work and little play. " I was up this morning," he writes to his father, " at 5.30 and studied and took my breakfast from 6 to 7, a class from 7 to 8, one from 8 to 9, from 9 to 3 laboratory (I lunch now to have more time for work, and don't dine till 6), and from 3 to 5 I studied, then from 5 to 6 lecture, and then I dined. And now at 8 I must start again." And so this was kept up all the time, curiously enough, with emphasis on organic chemistry, a branch of the science which Ramsay almost wholly abandoned in his later and most productive years till the time for the Ph.D. examin- ation. " On Monday at 7 it began and lasted till half-past 12; then in the afternoon from 3 to 8, so we had a good spell of it." The questions in chem- istry were: (a) the resemblances and differences be- tween the compounds of carbon and silicon, and (6) the relation between glycerine and its newer deriva- tives and the other compounds containing three atoms of carbon; in physics: (a) the different methods for determining the specific gravity of gases and vapors, and (b) the phenomena which may be observed in crystals hi polarised light. " I managed to answer the first perfectly, the second however, not so well, and the two questions in physics pretty well. Then to-night we had the oral exam. The five professors who com- pose the faculty were there. Fittig gave some very difficult questions. Reusch (Physics), on the other hand, very easy ones. . . . We had to dress up and put on white kids, and I had to get a ' tile ' especially for the occasion. Then we were sent out after the exam, for about 5 minutes and were then called in and formally told we had passed." 43 EMINENT CHEMISTS OF OUR TIME A dissertation on " toluic and nitrotoluic acids," which gave no glimpse of the future before him, com- pleted Ramsay's Ph.D. requirements, and he returned to Glasgow, where he became assistant in the Young Laboratory of Technical Chemistry. And now Ramsay had to turn his attention from organic to inorganic chem- istry, for most of the courses at the technical school were devoted to the latter. Though the physico- chemistry background was entirely lacking, and there- fore the knowledge obtained could hardly have been more than miscellaneous, innumerable facts were picked up and stored for future reference. An opening as tutorial assistant at Glasgow University offered the possibilities of a more congenial academic atmosphere, and also the hope of continuing his inter- rupted research hi organic chemistry. " The cellars of the University Laboratory contained a large collection of fractions of ' Dippel-Oil ' prepared by Professor Thomas Anderson. These were regarded by Ferguson (his successor), whose interest hi chemistry was almost entirely that of an antiquary, more or less hi the light of museum specimens, and he was horrified when Ram- say suggested that he should be allowed to * investi- gate ' them, but he eventually gave way to Ramsay's importunity. The result was a very substantial addition to our knowledge of the pyridine bases and their deriva- tives." l The chemistry of dyes and explosives was not to be his life work. How he turned from this to the more mathematical branch of the subject is ascribed by Ramsay himself to problems he encountered in attempts to determine the molecular weights of some of his organic compounds by the Victor Meyer vapor density method. But we must also add that Ramsay, with that 1 Sir James Dobbie. 44 WILLIAM RAMSAY instinct for detecting the truly important among a mass of new theories and facts, which was one of his greatest assets, early foresaw the part the new science of physical chemistry would play in the development of chemistry. Thus he was one of the earliest hi England to appreciate the true significance of Guldberg and Waage's Law of Mass action, just as, at a later date, he was among the first to seize upon and translate van't HofPs celebrated paper on the analogy between the state of substances in solution and the same when in a state of gas. The Victor Meyer method suggested to him experiments on the volume of liquids at their boiling point, and this in turn gave rise to a whole series of new possibilities, the experimental side of which kept him and his collabor- ators, particularly Young and Shields, busy even after he had settled in University College years later. 2 For six years Ramsay remained assistant at Glasgow University, and though during that time he had been a candidate for several chairs and lectureships, nothing came of any of them. So discouraged did he become that there was much discussion in the family as to the advisability of starting business as a chemical manu- facturer. But before this scheme could be put into execution a vacancy at University College, Bristol, presented itself. The story goes that his knowledge of Dutch saved the day. According to this account one of the members of the University Council, a minister, was much perplexed with a Dutch text in his possession, and Ramsay volun- 2 " It was while blowing the bulbs used in this research (the volumes of liquids at their boiling point), I believe, that he first became aware of the value of the asset he possessed for physical work in his skill as a glass-blower. He had learnt the art at Tub- ingen, although it was only in his later researches that his marvellous manipulative power was fully developed." Sir James Dobbie. 45 EMINENT CHEMISTS OF OUR TIME teered a translation. The result was Ramsay's appoint- ment by a majority of one ! The stipend was fixed at a minimum of 400 ($2,000) per year. " The professor," read the contract, " will be required to give three lectures per week for the first two terms, say 60 lectures, together with class instruction in connection therewith . , . and a short course of lectures in the third term. He will also be required to superintend the laboratory during the whole session, and to give evening lectures once a week during the first two terms, together with class instruction in connection therewith. . . . The scheme of the College contemplates the possibility of occasional lectures being delivered in neighboring towns by the Professor or his assistant. ... In connection with the Cloth working Industry, special instruction in dyeing, etc. may be required under an arrangement not yet concluded with the worshipful the Cloth-workers' Company of London." The professor, not yet turned thirty, was to be kept busy on the job, with very little opportunity for research an altogether minor consideration to the worthy coun- cillors. But they had not reckoned on Ramsay's energy and capacity. Determinations of the density of gases, of the specific volumes of liquids at their boiling point, of the vapor pressures and critical constants of liquids were soon in full blast. And then came those classical determinations on the thermal properties of solids and liquids, and on evaporation and dissociation, most of which was done with his assistant, Young, which con- tinued at full blast for the next five years until Ramsay's transfer to London. This appointment came hi 1887. By that time Ramsay's reputation was such that the following year he was elected an F.R.S. (Fellow of the Royal Society). 46 WILLIAM RAMSAY In London his physico-chemical researches were further extended. Among these, particular mention should be made of perhaps the most brilliant of them all the measurement of surface tension up to the critical temperature, which led to the well-known law supplying us with a method for determining the molecular weight of liquids. Here Ramsay had an able assistant hi Shields. In 1890 the British Association met at Leeds, and two of the great Continental founders of modern physical Chemistry, van't Hoff and Ostwald, were present. Ramsay, who represented the school in England, naturally took a keen interest in this meeting. " Ram- say and Ostwald met for the first tune as fellow-guests in my house, which became accordingly a sort of cyclonic center of the polemical storm that raged during the whole week. . . . The discussion was incessant. ... I re- member conducting a party to Fountains Abbey on the Saturday and hearing nothing but talk of the ionic theory amid the beauties of Studley Royal. The climax, however, was reached the next day, Sunday. The dis- cussion began at luncheon when Fitzgerald raised the question of the molecular integrity of the salt in the soup and walked round the table with a diagram to confound van't Hoff and Ostwald. . . . Ramsay was no silent spectator. Being a convinced ionist, he was eager in helping out the expositions of Ostwald, whose English at that tune was imperfect and explosive, and his wit and humor played over the whole proceedings. . . . It was the beginning of relations of great mutual sym- pathy and regard between Ramsay and Ostwald, which lasted till they were divided by their respective national sympathies at the unhappy outbreak of war." 3 8 Professor Smithells. 47 EMINENT CHEMISTS OF OUR TIME And now we come to a momentous event in the career of our hero. Lord Raleigh had for some time been en- gaged hi determinations of the exact densities of a number of gases. Among these was nitrogen. In his experiments Raleigh found that the density of nitrogen obtained from the air was slightly but consistently higher than that obtained from artificial sources. Writ- ing to Nature (1892) he says: "I am much puzzled by some results as to the density of nitrogen and shall be obliged if any of your chemical readers can offer sug- gestions as to the cause. According to two methods of preparation I obtain quite distinct values. The relative difference, amounting to about i/iooo part, is small hi itself; but it lies entirely outside the errors of experi- ment." The difference in the weights of one liter of the gas obtained in the one case from atmospheric air and in the other from ammonia varied by about 6 in 1,200, or about 0.5 percent, but the accuracy of the method did not involve an error of more than 0.02 percent. With that keen scent for any promising material Ramsay immediately took up the problem. Some years previous he had found that nitrogen is absorbed fairly readily by magnesium. This suggested to him that by first getting rid of the oxygen hi the air, and passing the remaining nitrogen repeatedly over heated magne- sium, any other gas that might possibly be present hi the atmosphere would remain unabsorbed. This tm- absorbed gas was isolated and found to give a charac- teristic spectrum. The name argon (Gk., inert) was given to the newly discovered ingredient of the atmos- phere. It proved to be more refractory than the com- paratively inert nitrogen : it just simply would not make friends and combine with any other element! Shortly after this, Ramsay's attention was called to some experiments of Hillebrandt, of the U. S, Geological 48 g WILLIAM RAMSAY Survey, in which he obtained a gas believed to be nitro- gen from certain minerals, particularly one called cleveite, but which was now suspected to contain argon as well. Ramsay lost no time. From it he obtained argon, to be sure, but also another gas, with a spectrum all its own, which showed it to be identical with an ele- ment present in the chromosphere of the sun, and which until then had been considered peculiar to the sun. Lockyer years ago gave the name " helium " to it, and now Ramsay had rediscovered it on mother earth. But let the discoverer himself tell the exciting news. On the 24th of March, 1895, he writes to his wife: 4 " Let's take the biggest piece of news first. I bottled the new gas in a vacuum tube, and arranged so that I could see its spectrum and that of argon in the same spectroscope at the same time. There is argon in the gas; but there was a magnificent yellow line, brilliantly bright, not coincident with but very close to the sodium yellow line. I was puzzled but began to smell a rat. I told Crookes, 5 and on Saturday morning when Harley, Shields, 6 and I were looking at the spectrum in the dark room a telegram came from Crookes. He had sent a copy here 7 and I enclose that copy. You may wonder what it means. Helium is the name given to a line in the solar spectrum, known to belong to an element, 4 Ramsay married Margaret, daughter of George Stevenson Buchanan, in August, 1881, soon after he had been appointed Principal of Bristol College a position he attained one year after his arrival in Bristol. This union proved a particularly happy one. " To have such a helpmate as my wife has brought me happiness which I must acknowledge with the greatest thankfulness." And at a later date he wrote to a friend: " You have got a good son and daughter and that is much to rejoice at. So have I." 6 Sir William Crooks, the famous physicist and chemist. & His two assistants. 7 12 Arundel Gardens, their home. 49 EMINENT CHEMISTS OF OUR TIME but that element has hitherto been unknown on earth. ... It is quite overwhelming and beats argon. I tele- graphed to Berthelot 8 at once yesterday' Gaz obtenu par moi clevite melange argon helium. Crookes iden- tifie spectre. Faites communication Academic lundi. Ramsay.' ... I have written Lord Raleigh and I'll send a note to the R.S. [Royal Society] to-morrow. . . ." The first public account of helium was given to a semi- bewildered audience at the annual meeting of the chemical society in 1895, on the occasion of the presenta- tion of the Faraday medal to Lord Raleigh. Further investigations proved that helium occurred hi quite a number of minerals and mineral waters. To Kayser, however, was left the proof of its presence in the air. Like argon it simply refused to combine with any other substance. To the ancients air was a source of investigation, and it had remained so. Till 1894 no one, least of all a scientist, 9 would have suspected the existence in the atmosphere of undiscovered elements. Ramsay and Raleigh's discovery shook the scientific world. Recog- nition came from all parts. Lord Kelvin, as president of the Royal Society, presented Ramsay with the Davy Medal, with the following comment: "... The re- searches on which the award of the Davy Medal to Professor Ramsay is chiefly founded are, firstly, those which he has carried on, in conjunction with Lord Raleigh, in the investigation of the properties of argon, and in the discovery of unproved and rapid methods of getting it from the atmosphere; and secondly, the dis- covery in certain rare minerals, of a new elementary gas which appears to be identical with the hitherto hypo- thetical solar element, to which Mr. Lockyer many years 8 A famous French chemist. 9 Cavendish, in 1785, did suspect some such possibility. 50 WILLIAM RAMSAY ago gave the name of ' helium." . . . The conferring of the Davy Medal on Professor Ramsay is a crowning act of recognition of his work on argon and helium which has already been recognised as worthy of honor by scientific societies in other countries. For his dis- coveries of these gases he has already been awarded the Foreign Membership of the Societe Philosophique de Geneve and of the Leyden Philosophical Society. He has had the Barnard Medal of Columbia College awarded to him by the American Academy of Sciences, and within the last few weeks he has been elected a Foreign Cor- respondent of the French Academic des Sciences." Such was the excitement aroused by these discoveries that even young students were filled with the epidemic. We are told that " answers to examination questions showed that oxygen as a constituent of our air was almost forgotten hi the anxiety on the part of the candi- date to show that he or she knew all about argon." But Ramsay had not yet sufficiently dumbfounded his scientific confreres. From a careful study of Mende- leeff 's periodic grouping of the elements, he came to the conclusion that another inert gas ought to exist between helium and argon, employing a process of reasoning quite analogous to one used by the celebrated Russian many years before when, with the help of his periodic table, he predicted the discovery of new elements. Ramsay ransacked every possible source for this new element: minerals from all parts of the globe, mineral waters from Britain, France and Iceland; meteorites from inter- stellar space all without result. A clue was at length obtained when he found that by diffusion argon could be separated into a lighter and heavier portion. This sug- gested the presence of the unknown gas as an impurity 'And helium, the inert gas, a chemical curiosity in 1895, is now displacing hydrogen in baloons! EMINENT CHEMISTS OF OUR TIME in argon. It was evident that the unknown gas, if present, could be there in minute quantities only to have escaped detection. That meant that the larger the quantity of argon employed the better the possibilities of getting appreciable quantities of the unknown con- stituent. A simple method of separating the constituents in a mixture of liquids is to boil the mixture, and collect fractions of the condensed vapor. Each constituent will usually go off at a fairly definite temperature. This, hi principle, was the method employed by Ramsay, and his assistant, Travers. They prepared to begin with, no less than 15 liters of liquid argon! " On distilling liquid argon, the first portions of the gas to boil off were found to be lighter than argon; and on allowing the liquid air to boil off slowly, heavier gases came off at last. It was easy to recognise these gases by help of the spectroscope, for the light gas, to which we gave the name neon or * the new one,' when electrically excited emits a bril- liant flame colored light; and one of the heavy gases, which we called krypton or * the hidden one ' is char- acterised by two brilliant lines, one in the yellow and one hi the green part of the spectrum. The third gas, named xenon or ' the stranger ' gives out a greenish- blue light, and is remarkable for a very complex spectrum in which blue lines are conspicuous." 10 A trio, neon, xenon, krypton, added to helium and argon making five new gases and all in the atmos- phere ! Further recognition came from the Chemical Society of London. They awarded Ramsay the Longstaff medal, given triennially to the Fellow of the Chemical Society who, in the opinion of the Council, has done the most to promote Chemical science by research. "If I may 10 Ramsay, quoted by Letts. 53 WILLIAM RAMSAY say a word of disparagement," added Mr. Vernon Har- court, the president, in presenting the medal, " it is " and here we can see the twinkle in his eye " that these elements (argon, helium, etc.) are hardly worthy of the position in which they are placed. If other ele- ments were of the same unsociable character Chemistry would not exist." Ramsay's studies on helium led him to ponder over this question: why is helium found hi only minerals which contain uranium and thorium substances which give rise to radio-active phenomena? Attempts to answer this led him into the field of radio-activity, with results which even surpassed his investigations on the inert gases of the atmosphere. In 1903, in conjunction with Soddy, he succeeded in proving that helium, an element, could be produced from radium, another ele- ment. The transmutation of the elements come to life again! Those poor, foolish old alchemists, we were always led to believe, wasted their lives in vain attempts to transmute the base metals into gold. And here comes the dashing Ramsay, bold, as usual, to audacity, and calmly announces that his experiments prove the alchemists not to have been such fools after all! Succeeding experiments on the action of radium salts on copper and lead solutions led Ramsay to believe that copper and lead can undergo disintegration into sodium and lithium respectively two entirely different ele- ments! These latter claims still wait to be verified, but there is reasonable hope for assuming that various experimenters throughout the world will soon undertake the task of carefully repeating the entire work, now that peace is once again with us. 11 A fitting award for these achievements was the be- stowal of the Nobel Prize to Ramsay in 1904. The dis- 11 See the article on Madame Curie. 53 EMINENT CHEMISTS OF OUR TIME tribution of the prizes took place in Stockholm on Decem- ber loth of that year, in the presence of King Oscar and the royal family, foreign ministers and members of the cabinet, and many leading representatives of science, art and literature. After speeches had been delivered by the vice-president and other representatives of the Nobel Committee, and of the Academies of Science, medicine and literature, King Oscar personally pre- sented Lord Rayleigh (prize winner in physics), Sir William Ramsay 12 (chemistry) and Professor Pavloff (physiology) with their prizes, together with diplomas and gold medals. 13 The distribution of the prizes was followed by a banquet, at which the Crown Prince pre- sided. Count Morner proposed the health of Professor Pavloff, Professor Petterson that of Sir William Ramsay, and Professor Hasselberg that of Lord Rayleigh. The following day Ramsay delivered a lecture on argon and helium at the Academy of Sciences, which was followed by a dinner given in his honor by King Oscar. Writing from Switzerland to a friend some weeks later Ramsay says: " We had a most gorgeous time for nearly a week, dining with all the celetrities, including old King Oscar. The old gentleman was very kindly and took Lord R. and me into his private room and showed us all his curiosities, the portraits of his sons when they were children and his reliques of Gustavus Adolphus and of Charles XII. The Crown Prince told Mag (his wife) that it was a difficult job to be a king, thereby confirming the Swan of Avon. He said that whatever one supposed a Norwegian would do he invariably did the opposite. Indeed there was nearly a bloodless revolution while 12 Ramsay had been created a Knight Commander of the Bath (K.C.B.) in 1902, which carried with it the title of " Sir." 13 The sum of money attached to each prize amounts to about $40,000. 54 WILLIAM RAMSAY we were there ; the Prime Minister of Norway was there and I believe the dilemma was only postponed." Ramsay remained at University College until 1912, when he retired. Two years prior to this, in conjunction with Dr. Gray, he determined the density of the emana- tion obtained from radium (which Ramsay named niton) involving the mastery of experimental detail which estab- lished him once for all as the great wizard of the labor- atory. The total volume of the gas under examination was not much beyond i/io cubic millimeter a bubble which can scarcely be seen. To weigh this amount at all accurately required a balance turning with a load not greater than 1/100,000 milligram. When war broke out Ramsay placed his services at the disposal of the government. Much he could not do. In July, 1915, he writes to a friend that he had had several huge polypi extracted from his left nostril. " I have stood them for years, one gets into the habit of bearing discomforts, but it is a great relief." The relief was to be only temporary. Another operation became necessary in November. "I was in the surgeon's hands on November loth and again on the isth, and he did an operation on my left antrum for a tumor, I believe very successfully. Since then, last Monday, I was irradiated for 24 hrs. with X-rays as a precaution against recurrence. Luckily it is of the kind which can be stopped by Radium. I have had a very bad time." He died on July 23, 1916. Ramsay had lived not a long life, but a very fruitful and happy one. Writing to president Ira Remsen, of Johns Hopkins, a few months before his death, Ramsay concludes his letter with " Well, I am tired, and must stop. I look back on my long friendship with you 14 as 14 Dating back to the Tubingen days. 55 EMINENT CHEMISTS OF OUR TIME a very happy episode in a very happy life; for my life has been a very happy one." Ramsay was many-sided. He was an excellent ex- ample of the very opposite of Punch's dry-as-dust philosopher. Among musicians 15 and among artists 16 he held his own, for he was an accomplished amateur in both groups. As a linguist he probably has had few equals among scientists. And those of us who, as late as 1912, heard him move a vote of thanks to Professor Gabriel Bertrand, of the Sorbonne, after the latter's lecture to the members of the International Congress of Chemists, will have formed a pretty good picture of his charm and ability as a speaker. Of the many letters that have been preserved, perhaps none sums up so well the characteristics of Ramsay as the following, written to his friend, Dr. Dobbie : "LE HAVRE, " Monday, the Something or other August, 1877. " My dear Debbie, " Some fool of a Frenchman has stolen all the paper belonging to the French Association, and has left only this hah* sheet with Le Havre at the top. From the pre- ceding sentence you will have already guessed that the French Ass. is capering around Havre at present, that I form one of the distinguished foreign members, and 15 " I spent many evenings at their home, where William (Ram- say) enlivened the company with songs, which in later years were greeted with enthusiastic applause by his students at social evenings of the University College Students* Club. ... He had a very good voice, played his own accompanyments, and was an expert whistler." Otto Hehner, a friend. " " Another amusement of Ramsay's was sketching in water colors, an art in which he possessed no inconsiderable share of the talent which belongs to his cousins, Sir Andrew Ramsay's family." Sir James Dobbie. 56 WILLIAM RAMSAY that all is going as merrily as a marriage bell. Voici 5 jours that I find myself here. I went to Paris with three spirits more wicked than myself, lawyers a fear- ful compound 3 lawyers and a chemist just like NCU for all the world, liable to explode at any moment. . . . I have made the acquaintance with a whole lot of chem- ists, Dutch and French, and have found an old Dutch- man named Gunning ravished to find someone who shares his ideas about matter, chemical combination, etc. We excurted yesterday the whole day and talked French and German alternately all the time. When we wanted to be particularly distinct French was all the go. For energy and strong denunciation German came of use. You can't say * Potz-teufel ! ' in French or * Donnerwetter potztausend sacramento ! ' An old cove, also a Dutchman, DeVrig, with bowly legs and a visage like this (sketch profile) is also a very nice old boy. The nose is the chief feature of resemblance in the annexed representation. Wurtz and Schukenberger are both Alsatians and of course are much more ge- muthlich than the echter Franzose, but on the whole the fellows I have got to know are very pleasant. Some of the younger lot and I kneipe every evening. Then we bathe every day too in fine stormy water. 17 Eh bien, what is there to say of more? I am going straight back to Glasgow on Wednesday by the special steamer to 17 " He (Ramsay) was a very strong and graceful swimmer and could dive further than any amateur I have seen. When we were in Paris in 1876 the four of us used to go to one of the baths in the Seine every forenoon, and after the first time, when Ramsay was ready to dive, the bathman would pass round the word that the Englishman was going to dive, and everyone in the establish- ment, including the washerwoman outside, would crowd in and take up positions to watch him. He dived the whole length of the bath and sometimes turned there under water and came back a part of the length." H. B. Fyfe, a life-long friend. 57 EMINENT CHEMISTS OF OUR TIME Glasgow. My money is about done, so I must bolt. ... By the way I forgot to tell you that I had the cheek to read a communication on picoline, in French, which was received with loud applause. There was some remarks made afterwards very favorable, tho' I say it as shouldn't say it. Adoo. Write to Glasgow and tell me Wie's Geht. " Yours very Sincerely, "W. RAMSAY." References For much of the material I am indebted to Tilden's life of Ramsay (i). A fine appreciation of Ramsay at his prime is given by Ostwald (2). Soddy's (3) is a lovely tribute by a gifted writer. T. C. Chaudhuri (4) is responsible for an appreciative little memoir, full of oriental coloring. Ramsay's two books (5, 6) deal with the gases of the atmosphere and radium. 1. Sir W. A. Tilden: Sir William Ramsay (Macmillan and Co. 1918). 2. Wilhelm Ostwald: Sir William Ramsay. Nature (London), 88, 339 (1912). 3. Frederick Soddy: Sir William Ramsay. Nature (London), 97, 482 (1916). 4. T. C. Chaudhuri: Sir William Ramsay (Butterworth and Co., India. 1918). 5. William Ramsay: The Gases of the Atmosphere (Macmillan and Co. 1902). 6. William Ramsay: Essays Biographical and Chemical (Constable and Co., London. 1908). (See the chapter on radium and its products.) THEODORE WILLIAM RICHARDS lURING the latter half of the nineteenth century William T. Richards rose to a posi- tion of prominence among American artists. His paintings of landscape, particularly his interpretations of the varying aspects of the ocean beat- ing upon beach and rock, won high praise and eventually earned for him the gold medal of the Pennsylvania Academy of Fine Arts. His wife, Anna Matlock, whom he married in 1856 when some twenty-odd years old, was like her husband, a woman of artistic talent, though in her case it showed itself in the publication of verse. Of their six children, one of whom, Herbert Maule, is to-day a professor of botany at Barnard College, and two others, Mrs. Eleanor French Price and Mrs. Wm. Tenney Brewster are painters, we are particularly inter- ested in the fourth, Theodore William, who was born in the house of his grandfather, Dr. Charles F. Matlock, hi Germantown, Philadelphia, on Jan. 31, 1868. The family were in very comfortable circumstances. In addition to their home in Germantown they had a summer one in Newport, and occasionally they would forsake both for extensive travels in Europe. The poor schools in Pennsylvania at that time, as well as the uncertainty of the family's stay at any one place for any length of tune, made it necessary for the children to receive privately their most elementary education. For this task Mrs. Richards was eminently well fitted. Young Theodore gradually passed from " Alice " to history and languages, and with little effort quickly over- took his playmates who attended school. 59 EMINENT CHEMISTS OF OUR TIME Naturally the boy's first desire was to become an artist. Was not his father the greatest of men, and could a son of his do less than follow in his footsteps? Filial reverence lost none of its force with time, but a desire to paint, slowly and quite unconsciously, gave place to a desire to become a scientist. This showed itself even before he was thirteen. The query naturally suggests itself, what started him on this track? His mother and father, aside from art, were very much interested hi Tennyson and Browning, and literature hi general. An intimate friend of the family's was Frank R. Stockton, the author. From none of these three could Theodore have obtained much sci- entific inspiration. There remained then his grandfather, the doctor, and still another close friend of the family's Josiah Parsons Cooke, Professor of Chemistry at Harvard. That the boy got much of his inspiration from this Harvard pro- fessor seems pretty certain. Even before he entered Harvard Young Richards had already mastered Cooke's The New Chemistry, and was quite a match for many of the students with several years' chemistry to their credit. Genius young Richards could well have inherited, in part at least, from his parents; the bent of this genius towards science must to a certain extent be credited to Cooke; but the further quality of taking infinite pains with details, so essential to every scientist, and one which Richards possesses in a supreme degree, seems to have been directly transmitted from father to son. Note this description of the artist: "He stood for hours hi the early days of Atlantic City or Cape May with folded arms, studying the motions of the sea until people thought him insane. After days of gazing, he made pencil notes of the action of the water. He 60 THEODORE WILLIAM RICHARDS even stood for hours in a bathing suit among the waves, trying to analyse the motion." Yet still another inheritance. What soon strikes a reader hi glancing over Richards' contributions to chem- istry is the fine unity of purpose which pervades all his work: a desire to penetrate ever deeper into the myster- ies of creation. This philosophical bent may be traced to his mother, whose verses abound with fine feeling and deep thought. Richards, barely fifteen, entered Haverford College, Pennsylvania, with this advice from his mother in his pocket: Fear not to go where fearless Science leads, Who holds the keys of God. At Haverford, aided by a retentive memory and a desire for knowledge, Richards made rapid strides, particularly in chemistry and astronomy. But he was not a bookworm ; though somewhat delicate hi physique, with eyes that needed careful nursing, he took an active part hi the less strenuous exercises such as lawn tennis, skating and swimming. But Cooke was not at Haverford, and Richards wanted Cooke. He wanted him badly now because he, Richards, also wanted to be a chemist, and because he, like Cooke, was particularly interested hi the philosophy of chem- istry. Then there were other men at Harvard whose acquaintance Richards was anxious to make. Wolcot Gibbs, C. L. Jackson, and H. B. Hill were men who counted hi chemical councils of the day. Richards, then, wanted to complete his bachelor's degree at Harvard. The reasons he gave for desiring to change were quite sufficient for his parents. They understood and encouraged, as they continued to do to the end of their days. Their motto from the first was : give him the best that's in you, but let nature play its 61 EMINENT CHEMISTS OF OUR TIME part; guide much, but force nothing. So Richards set out for Cambridge, there to join the senior class. In the following year (1886) Richards splendidly justi- fied the cherished hopes of his parents by graduating with summa cum laude and highest honors in chemistry. There could be no further question as to his future. He had made a brilliant start in chemistry, and chemistry it was to be. When one considers the extent to which research in America is carried to-day it comes as a surprise to learn that even as late as 1880 very few research investigators were to be found at any one of the colleges. At Harvard, for example, although the Erving Professorship of Chemistry had been founded as early as 1792, Josiah Parsons Cooke (1827-94) was the first occupant of the chair to take any real interest in investigations. These led to problems dealing with the combining proportions of elements to form compounds. Combining proportions of elements is glibly enough discussed by every high school boy, but Cooke could penetrate much below the surface of things, and Cooke led his students on his own philosophic path. Needless to add, Richards was one of the enthusiastic followers. Under Cooke's guidance Richards began an investi- gation of the atomic weight of oxygen. [See the article on Mendeleeff for the meaning of atomic weights.j Richards soon showed that the accepted atomic weight for oxygen was too high. But more than that: the method of procedure had elements of novelty, and the extraordinary care taken to avoid errors in manipulation centred attention upon the work. The use of copper oxide in the determination of the atomic weight of oxygen made it most desirable to be certain of the purity of this substance. Its somewhat 62 THEODORE WILLIAM RICHARDS anomalous behavior led the young investigator to ques- tion the accuracy of the accepted atomic weight of copper, and by a careful investigation of the matter, in the course of which he showed that the copper oxide which previous investigators had used contained nitrogen as an impurity, Richards came to the conclusion that the atomic weight of copper as given by other investi- gators was too high. The differences to be sure were fractions of one percent, but they were entirely beyond all possibilities of experimental error. These two researches were conducted before Richards reached his twentieth year. Two results immediately followed therefrom: the boy Richards had become a force to be reckoned with, and he had discovered just that particular department of the science for which he was best fitted. In 1888, at the age of twenty, Richards received his Ph.D. " Before this, the greatest wish of my life had begun to develop namely, an intense desire to know something more definite about the material and ener- getic structure of the universe hi which our lot is cast. Advancement in academic position, although prized because necessary in order that a normal life should be possible, was subordinate to this great interest. At first perhaps my desire began as a feeling little above mere curiosity, but by degrees I realized that gain in knowledge would mean for humanity gain in power, which I thought of primarily as gain in power for good. By instinct and education, although not by formal connection, I was of the Society of Friends (or Quakers), in whose minds peace and goodwill to men were foremost; and I dwelt little upon the sinister uses to which the increased power found by science could be put. ... It is not the fault of science if mankind is so little civilized as to misuse its great potential benefits. ..." 6 63 EMINENT CHEMISTS OF OUR TIME " The atomic weights seem to be among the primal mysteries of the universe. They are values which no man by taking thought can change; they seem to be independent of place and time. They are silent wit- nesses of the very beginnings of things, and their half- hidden, half-disclosed numerical relations, in connection with the undoubted similarities in chemical properties of certain groups of elements, only increase one's curiosity concerning them. . . ." We see here clearly enough that even thus early in life atomic weight determinations to Richards were a means and not an end. To get finally at fundamentals required in the meantime years of patient labor, ingenuity and skill. Richards, of course, was not the pioneer in atomic weight determinations. From the time of Dalton more than one hundred years ago, many workers had pointed out their significance. Prominent among these were Avogadro and Cannizzaro, two Italian scientists; Ber- zelius, a Swede; and Stas a Belgian. The classi- fication of the elements based on their atomic weights resulted in MendeleefFs Periodic Law, which in turn gave rise to much further experimental work to explain apparent inconsistencies in the then accepted atomic weights. Mendeleeff's Law also offered food for much reflection. Why could the weights of the elements be so arranged as to exhibit at a glance the close chemical and physical relationship of many of them? Was this relation due to their origin from some parent substance? Reflections such as these led Richards to the view that an answer to such a question could be obtained only by a much more careful examination of properties of the elements, and among these, atomic weight stood first on the list. 1 1 Recently (1913-1914) Mosely, an English physicist, by studying the high-frequency spectra emitted by different elements when used 64 THEODORE WILLIAM RICHARDS The great promise he had shown, and the hearty sup- port which he received from Cooke, enabled Richards to secure one of those valuable Harvard Travelling Fellow- ships, and during 1888-89 he spent much of the time at Gottingen, where he became acquainted with Victor Meyer and his vapor density method, Walter Hempel and his gas manipulations, and worked directly with Paul Jannasch on the estimation of oil of vitriol in the presence of iron. On his way home he stayed in England long enough to form friendships which were to prove life-long. What Richards got from his travels abroad is much what the young graduate gets by attending large sci- entific gatherings; he saw in flesh and blood men whose fame had reached him, he was introduced to some of them, and caught their enthusiasm and lofty vision. On his return to Harvard Richards was appointed to an assistantship, and two years later he became an in- structor. Needless to add, the interrupted work on as targets in an X-ray bulb, has shown " that there is in the atom a fundamental quantity, which increases by regular steps as we pass from one element to the next. This quantity can only be the charge on the central positive nucleus." Mosely, quoted by Lowry, Historical Introduction to Chemistry, p. 493, 1915. (See also the article on Madame Curie.) Mosely's " quantities," the " atomic numbers," are the source of much scientific activity at present. Of Mosely, the author of these "atomic numbers," who was killed in the Great War, Prof. R. A. Millikan, the distinguished physicist of the University of Chicago, has this to say: " In a re- search which is destined to rank as one of the dozen most brilliant in conception, skilful in execution, and illuminating in results in the history of science, a young man but twenty-six years old threw open the windows through which we can now glimpse the subatomic world with a definiteness and certainty never even dreamt of before. Had the European war had no other result than the snuffing out of this young life, that alone would make it one of the most hideous and most irreparable crimes in history." 65 EMINENT CHEMISTS OF OUR TIME atomic weights was resumed with vigor. Some finish- ing touches which he gave to his copper work, hi the course of which barium in the shape of one of its salts had to be used, pointed to the next line of attack. His results led him to the view that the atomic weight of barium was even less well known than that of copper had been. We see that the elements were never selected at random, but like most careful and thoughtful work, one experiment led to another, and each succeeding experi- ment showed elaborate improvements over its prede- cessor. Thus in this barium determination Richards first carefully chose a compound of the element which could be easily prepared in the pure state, which could be dried without decomposition, and which could be readily analysed. The compound once selected, it was now prepared in no less than seven different ways, and each one was found to have the same composition. Such was the accuracy of the procedure that two of the results for the atomic weight of barium differed by no more than one six-thousandth of an ounce, and these were shown to vary markedly with the value then in vogue. The errors which other experimenters had fallen into with their barium determinations made it more than probable that those errors had been repeated with strontium, an element chemically very closely allied to barium. Such, indeed, proved the case; and here, as before, new figures were given and the old errors ex- plained. In this strontium experiment Richards set a record for exact methods of procedure which have never been surpassed, and which formed the basis for most of his subsequent work on atomic weights. Here, also, by the introduction of his bottling device, which gave assur- ance that purified materials could be kept uncontami- 66 THEODORE WILLIAM RICHARDS nated with any moisture, and the use of the nephelo- meter, which detected minute traces of suspended material, "two errors were obviated . . . which have perhaps ruined more previous investigations than any other two causes. . . ." The standards which Richards has set for his work are summed up in this remark of his: "Every sub- stance must be assumed to be impure, every reaction must be assumed to be incomplete, every measurement must be assumed to contain error, until proof to the contrary can be obtained." Such merit could not go unrewarded; in 1894 Rich- ards was promoted to an assistant professorship. In the following year the fame of Ostwald's school at Leipzig, and the desire to become more proficient in physical chemistry, a science which he clearly foresaw he would use extensively, led him once again to Ger- many, and here he remained for a semester. Not long after his return Richards married Miss Miriam Stuart Thayer, the daughter of Professor J. H. Thayer, the New Testament scholar. They have a daughter and two sons. Fame Richards had already attained, but there was a danger in another direction. Aside from his salary, Richards had nothing, and the salary was too small for a man with family. Passionately interested as he was in research, Richards realized only too clearly that it was mot a " money-getting-employment." " Money-get- ting " meant weary hours of labor, and such occupation could hardly be engaged in, side by side with research, without impairing either the one, or the other, or, what is worse, one's health. At this critical hour the father istepped in: " My father . . . advised me to devote myself . . . to research ... he supported this advice in a very 67 EMINENT CHEMISTS OF OUR TIME practical way and offered ... to help me, out of his none too plentiful means, in case of a pinch, rather than permit me to engage in the distracting task of making money by occupations outside of my main interest. Later, after my marriage in 1896, when new cares presented themselves, and when he saw that there was danger of my overworking, he placed into my hands a sum of money large enough to enable me to feel that I could take a year's rest from academic work, if that should prove necessary. The relief from worry, afforded by this sum hi a savings bank, made the vacation unnecessary." " There is no question that this generous and thought- ful confidence was a very important factor in the success of a not very optimistic and somewhat delicate young man, then entirely without any capital except his brains; and it would be impossible to exaggerate my feeling of gratitude. My wife also heartily sympathised with my desire to conduct investigation, and did all in her power to encourage the work." Encouraged in this way, Richards threw himself into his work with a wholeheartedness and enthusiasm which knew no bounds. Step by step, with one research giving rise to another, he redetermined the atomic weights of such elements as zinc, magnesium, nickel, cobalt, iron, silver, carbon, nitrogen, etc., and in each case the figures he obtained showed differences with those obtained by other workers, many of whom were masters in the field. These differences were shown to be the necessary result of various inaccuracies which other men had fallen into, inaccuracies, in many cases, due to a lack of knowledge of certain very necessary physico-chemical principles. As showing the uniform excellency of Richards' work it may be pointed out that in every instance the consensus of scientific opinion has 68 THEODORE WILLIAM RICHARDS been overwhelmingly in favor of his results. " One's confidence in the work," writes Richards, " cannot but be increased by the fact that in spite of the many years which have passed since some of the work was done [this was written in 1910], not one of these values has been shown to be seriously in error, and in every case the Harvard value has been accepted by the International Committee on Atomic Weights and by the world at large as more accurate than previous work of others." Much of his earlier work appeared in the Proceedings of the American Academy of Arts and Sciences, but with the growth of the American Chemical Society, and the consequent growth of its Journal, many of the more recent papers have found their way into this Journal. Some have been reprinted by the Carnegie Institution of Washington, an organisation which, by its financial assistance, has made much of the work possible. A volume embracing all of Richards' papers up to 1909 was published in German under the title, Untersuchungen iiber Atomgewichte. The extent of these researches has necessitated the assistance of many students. These flocked to Harvard in large numbers. As early as 1895, when Richards was but 27, students began to work under his direction, and their number has steadily grown until to-day there is quite a little army of them. Some of them, such as G. N. Lewis, L. J. Henderson, Grinnel Jones, Baxter and Cushman, are already among the very best chemists of America. In 1901 Richards was appointed to a full professorship at Harvard. This came after his declination of an offer from the authorities at the University of Gb'ttingen, Germany, which showed how far his fame even then had travelled. Two years later he was made chairman of the department, and in 1907, in fulfilment of arrangements which had been entered into between Harvard and the 69 EMINENT CHEMISTS OF OUR TIME German Government, Richard was selected as Exchange Professor at Berlin University for that current year, and during his brief stay there he introduced some of his classical experimental methods into German laboritories. Before his departure from Berlin, Richards delivered an address to the members of the German Chemical Society. From a description in the Chemiker-Zeitung we gather that the big amphitheatre in the Hofmannhaus (the headquarters of the Society) was filled to over- flowing, " scholars from every part of the country being attracted." Among the audience were such well- known chemists and physicists as Graebe (the president), Emil Fischer, Landolt, Nernst, Lampe, Brauner, Lieber- mann, Buchner, Planck, Pinner, Ladenburg, Gabriel, Witt, Bernthsen, Warburg and Biltz. Richards' address, dealing with his later researches on atomic weights, was received with much enthusiasm (" Der Vortrag wurde mit ausserordentlichem Beifall aufgennomen "), and the president in his comments, declared that the two foremost authorities on atomic weights in the last hundred years, Berzelius and Stas, now gave way to Richards. " The light, which before radiated from Europe to America, is now brilliantly reflected back again." It has been emphasised that Richards' atomic weight determinations were merely a means, and that the end in view was a deeper knowledge of fundamentals. This led him to investigate other properties of the elements besides weight, such as compressibility, melting point, etc. The development of a theory which assumed that atoms, and not merely the spaces between them, are compressible has borne wonderful fruit, and has splen- didly correlated many properties of matter. " In developing this theory, I endeavoured always to avoid confounding hypothetical inferences with reality, trying 70 5" "V <^ -. 5 b^ l^ ^3 s ^^ r ^Ci s 9i p ^*s s ^ fc \ . , \ i \ ^C S ^ ij 4: S -\ 3s v. 1 M v J- j* 7 f" K / Sj ^j- / / J / r j / / / / / / /2 / / / r <5 / / ^ 0, N ' r 3 JS . _J -== c: ^ ^ / e= F ^ ^TH -^ ^ ' !* I r .Mu. - - r=w* ^C II !- =^ ~4r ~ S ft ^. *? k ~ * '- ^ ^ N \0 V ^ a. * \ P 'o c^ ^ ; IP V s 5 X, .C s( "i V ^- -Jjlo 1?*" L, to <3 ^x 1 ^ X; ^ I 3 fg 1 1 x: \ i <5 J S Is s * ! } -K4 v j 2 N d- ^ ^ / > S v> i ' k ^*+ ,3- ^ S a a - ,-* i i- " r ^, i 5T __. | w> x N ^. \ ^ -. ^, =^i *^ ^: ^ ^ ^ ;- "' / <0 / ; -^ \ ^ 1 2 ,c: /, 5;- 7 \ JviJ a < N ^i Ki -\ * \ c : 7 T ty _ U. S 9o / . X /r "k- r= = * - L w ^= \ ^ *=-r i? ^ = 1 , c! ^_ ~ssr* mmm* jS. T ^-\ CL K, ^ - ty r~ - . -^9^ . ' *- ~^i ^ - trJO ^1 -s>i ^ q ^ ^* *>' 3 ^3 ^ : . ... . -4 ; ,-^- - ' "^ ^ ^ ^ S ^ c^ ^> x ^x .9* a*"" ^- ^^^ **~ ^ ~ ^ -*** ^> ^ i 1 ^ ^ ^ 5 1 l - II si ' a i I 2| 5 S is 31 Ci' S 8 8 ^ THEODORE WILLIAM RICHARDS to follow in the footsteps of Michael Faraday, who always distinguished between the dreams and the facts." How well various properties of elements are correlated is graphically represented on the opposite page, the curves being a reproduction from one of Richards' most recent papers. Even a casual glance at these curves will answer the few critics, quite ill-informed as to the nature of the work, who, though readily admitting Richards' extra- ordinary skill in technique, claim that it shows no striking originality. We have heard similar remarks made of Richards' illustrious co-worker at the Harvard Medical School, Otto Folin. Folin has devoted much of his time to the improvement of the quantitative methods em- ployed in urine, and later, in blood analysis. Aside from having shown how unsatisfactory many of the quanti- tative methods previously used are, and, as a conse- quence, how worthless are all the conclusions of a chemi- cal nature drawn from them, Folin has been led, among other things, to his beautiful theory of protein meta- bolism, which is the very cornerstone of clinical teaching to-day. Folin's improvement of quantitative methods had all these possibilities in mind. Precisely the same is true of Richards' improvements of atomic weight determinations. Quantity, through Lavoisier, laid the basis of our modern science of chem- istry, and the greater the refinements in quantitative methods the greater the progress. In Richards we have not only a master of quantitative manipulation, but a master interpreter of these procedures, and it is the com- bination which makes him a great master in our field. 2 2 As showing how quite unexpected practical applications may result from work of scientific interest only, the following may be cited: copper ore is purchased upon a metal value, established by chemical analysis, a value based upon the weight of copper atoms EMINENT CHEMISTS OF OUR TIME In 191 1 Richards was presented with the Faraday Medal of the English Chemical Society, and on this occasion delivered an address The Fundamental Properties of the Elements, which is one of the most stimulating the present writer has ever read. Of the impression it made on its hearers, Prof. Dixon's opinion may be quoted : 3 " We have listened to-night to a story that is more entrancing than any fairy tale, because as we followed the flight of the lecturer's imagination, we knew that that flight was surely guided and controlled by a man who has measured and weighed the elements with an accuracy hitherto unknown. Concerning the weights of the element, our old European ideas of finality have been overthrown by Professor Richards and his school, and we are at this moment seeing the fulfilment of the prophecy of Canning when he said, * I look to the new world to redress the balance of the old."* The following year Richards was appointed to the Erving Professorship of Chemistry and made Director of the Wolcott Gibbs Memorial Laboratory, a post which he still holds. This Wolcott Gibbs Laboratory, which was completed in 1913, and which is devoted exclusively to research hi physical and inorganic chemistry, was named after one of Harvard's professors of chemistry. Its erection was made possible through the generosity of the late Pro- fessor Morris Loeb, himself a pupil of Wolcott Gibbs. in the ore. Until the Harvard experimental results were announced this atomic weight was represented as 63.2; whereas the experi- ments showed the figure to be 63.6. Evidently this difference of two-fifths of one percent means an increase in value to the seller of about $4,000 on one million dollars' worth of ore. 8 Dixon is professor of chemistry at the University of Manchester, and one of the past presidents of the English Chemical Society. 72 ! is o ^2 C 31 THEODORE WILLIAM RICHARDS For the type of work in which Richards is engaged the Gibbs Laboratory is probably the best equipped in the world. The building has six floors available for work: three regular stories, a very light and convenient basement, a sub-basement for especially constant temperature work entirely underground, and a practicable roof. It con- tains no lecture rooms but is divided into many rooms of small sizes, the majority of them intended for one or two investigators. Balance rooms, 4 dark rooms, rooms designed for chemical and physical laboratories (because much of the work lies on the border-line of physics and chemistry), and other prerequisites for accurate ex- perimentation, abound. Pipes are laid for hot and cold water, distilled water, steam, compressed air, oxygen, and vacuum, as well as for gas ; and electricity of many voltages is available at suitable plugs throughout. An automatic electric lift is used for transferring the appa- ratus, and telephones connect all the important rooms. Hollow bricks and doubly glazed windows with tight weather-strips protect the building from heat and cold, and the temperature of almost every room is auto- matically regulated. The ventillating plant provides filtered air, hence the building is extraordinarily free from dust throughout. But we have yet to tell of Richards* greatest triumph, a direct result of his atomic weight determinations. In the spring of 1914 Richards startled the scientific world 4 The balances weigh accurately one forty-millionth part of an ounce. With their aid it is possible to weigh a short light mark made by a lead pencil. The material is weighed in a platinum receptacle which is carefully regulated to the temperature of the rest of the balance, otherwise an ascending current of air would be generated if the crucible were even slightly wanner, making it lighter on the balance. The balance is confined in a glass case containing dried air. 73 EMINENT CHEMISTS OF OUR TIME by his announcement that lead obtained from radio- active minerals has a lower atomic weight than the lead obtained from any other source. A little reflection is needed to appreciate the full sig- nificance of this statement. Until then no case of vari- ation hi the atomic weight of an element had ever been shown. Copper, silver, iron, etc., had been obtained from various ores in different parts of the world, and many thousands of analyses had been run by many hundreds of investigators everywhere, yet the atomic weight of each element remained a fixed number. Wherever variations arose, these were invariably traced to inaccuracies in experimentation; and indeed a fixed tenet hi the faith of every chemist became that the atomic weights of the elements are unalterable. But radioactivity came to shake this faith, as it has shaken the faith of so many other scientific beliefs. Who was to settle such a question if not the master of atomic weight determinations? Ramsay and Soddy in England, and Fajans and Bredig in Germany, urged Richards to undertake this work. Fajans sent his assistant, Max Lembert, with several valuable samples of radio-active ores containing lead, to assist in the research. Radioactive ores from Ceylon, from Colorado, from England, from Bohemia, from Norway, were carefully purified, and the atomic weight of the lead present deter- mined with all the extraordinary refinements that his brother workers expected of Richards. The mean of many results gave the value of 206.6 for the atomic weight of radioactive lead, as compared to 207.2 for common lead a difference small enough, but altogether beyond any experimental error. The most amazing feature of the whole situation was that, outside of this difference in atomic weight, and, therefore, density, the two varieties 74 THEODORE WILLIAM RICHARDS of lead were exactly the same in all respects, physically and chemically. "Now Rutherford and Soddy had worked out a theory of radioactive disintegration by which, starting with uranium, that element broke down in stages into a number of other elements, the last of which was lead. From this hypothesis the theoretical atomic weight for lead could be deduced. This was found to be 206.07. Richards' experimental figure was 206.08, a difference then of one one-hundredth, and a percentage difference of about one two-thousandth. Never in the history of science was there a more complete agreement between theory and fact. This had its award in the Nobel Prize which came to him in that year (1914). In 1916 Richards was awarded the Franklin Medal of the Franklin Institute, Phila- delphia, founded for the recognition of those workers in physical science or technology, without regard to country, whose efforts, in the opinion of the Institute, have done most to advance a knowledge of physical science or its applications. In addition to these awards, Richards has been the recipient of many other honors. At various tunes differ- ent universities Yale, Harvard, Cambridge, Oxford, Manchester, Prag, Christiania, Haverford, Pittsburgh, Clark and Berlin have granted him honorary degrees. In 1910, the London Royal Society bestowed its Davy Medal upon him, and in 1912 he received the Willard Gibbs Medal of the American Chemical Society. He has been twice elected to the presidency of the Ameri- can Chemical Society. In 1917 he was elected President of the American Association for the Advancement of Science for that year. Recently (May, 1919) he was nominated for the presidency of the American Academy 75 EMINENT CHEMISTS OF OUR TIME of Arts and Sciences. He is a member of most of the scientific organisations of Europe and America. Here is a reporter's description of the man and his surroundings: " You find the offices of the director on the second floor. Presently the door of the inner room opens and you hear the conclusion of a little conference. . . . There are some remarks about * the determination of Q and the elimination of that error, 1 and then you are invited into the private apartment of Professor Theodore William Richards. . . ." "The room is large and cheerful and the visitor is slightly surprised to note that it contains few tokens of the laboratory work to which the building is dedicated. . . . The eye catches at once an artistic portrait upon the wall of a chemist at work with his retorts and tubes, and inquiry secures the information that this is a photo- graph of a Burne-Jones painting of [the late] Lord Raleigh, the Chancellor of Cambridge University [and the renowned physicist]. Above the mantle stands a portrait of Michael Faraday. "The visitor expresses some surprise as he notes also that several water-color drawings adorn the room. ' Is there any reason why such a room should be devoid of beauty? ' asks the Director, and later you learn that Prof. Richards himself likes to sketch. . . . Two of the water colors are the work of his father, one a scene at Monhegan, the other a view of rocks, shale and waves at Newport. " Meantime you have been studying the man himself. He is of medium height, sturdily made, with grey hair, eyes that look keenly through his glasses, and a genial manner. His face is oval, the smile comes readily he confesses to a feeling of humor, as might be surmised from the twinkle that frequently is caught lurking in his eyes and the movements are quick and definite. The 76 THEODORE WILLIAM RICHARDS general impression is that of a business man with many affairs pressing upon his attention rather than that fancy which most persons have of a chemist working with minute and patient care upon some scientific problem." And now let Prof. Richards act as autobiographer: " Although I have been able to accomplish only a very small part of that which has been planned, the work has interested the chemical world beyond all expectation; indeed the possibility of much outside interest had not been anticipated. . . . The splendid Nobel Prize (which has grown to be world-renowned above all other forms of recognition, not only because of its magnificence [some $40,000 go with it] but also because of the list of great men whose names grace its earlier records), gave pleasure which it is impossible to exaggerate. " The award will be a lively inspiration to try to do better work in the future, and, moreover, its provisions will help to smooth the way toward more accomplish- ment, both by providing help for the present, and by relieving worry for the years to come. " All those marks of kindness and generosity on the part of one's friends and colleagues bring great satis- faction and happiness; but they cause also a sense of humility and responsibility. One cannot help wishing that one's incomplete attainments, so richly rewarded, came nearer to the ideal; and one cannot help feeling that he must strive doubly hard in the future to be worthy of having received such great tokens of confidence and honor." Richards, together with his students, has thus far published some 200 papers the results of research. Many of them have become classics in our science. Yet Richards is very little over fifty to-day. What may we not expect in the years to come ! 7 77 EMINENT CHEMISTS OF OUR TIME References Part of the information comes from private sources. Morris's life of Richards' father (i) gives us a picture of the family. Richards himself is responsible for a delight- ful autobiographical sketch of his early days, prepared at the request of the editor of the Swedish Vecko- Journalen (2). An unusually well-informed newspaper account of Prof. Richards and his work appeared in the Boston Sunday Herald in 1915 (3). A description of the Wolcott Gibbs Memorial Laboratory appeared in the Harvard Alumni Bulletin for 1913 (4). Excellent sum- maries of Prof. Richards' work may be found in Science for 1915 (5), 1916 (6) and 1919 (7), and in the English Chemical Journal (8), 1. H. S. Morris: William T. Richards. A Brief Outline of his Life and Art (J. B. Lippincott Co., Philadelphia, 1912). 2. T. W. Richards: Retrospect. Vecko Journalen (Stockholm), Feb. 20, 1916. 3. Aonn.: Professor Richards Wins Nobel Prize. The Sunday Herald (Boston), Nov. 21, 1915. 4. T. W. Richards: The Wolcott Gibbs Memorial Laboratory. Harvard Alumni Bulletin, March 26, 1913. 5. T. W. Richards: Recent Researches in the Wolcott Gibbs Memorial Laboratory of Harvard University. Science , Dec. 6. T. W. Richards: Ideals of Chemical Investigation. Science, July 14, 1916. 7. T. W. Richards: The Problem of Radioactive Lead. Science, Jan. 3, 1919. 8. T. W. Richards: The Fundamental Properties of the Elements (Faraday Lecture). Journal of the Chemical Society (Lon- don), 97, 1201 (1911). JACOBUS HENRICUS VAN'T HOFF [OU have two substances: they both have the same atoms, the same number of atoms, in the same proportion by weight. So far as you can make out, they both have the same structural formula. Yet they show decided differences in properties. They have different crystalline struc- tures and different optical properties, for example. What are we to make of this? Such was Pasteur's problem with his famous tartaric acids. Such was Wislicenus's difficulty with his lactic acids. Structural formulas, as written on paper hi two dimensions therefore failed utterly to show any differences in these compounds. Now, of course, it did not require any very keen insight on the part of Pasteur, Wislicenus, and others, to realise that real molecules occupy not two but three dimensions, and that at best, paper formulas were a use- ful, but not a real mode of representation. Were the differences in these compounds to be ascribed to differ- ences in the internal structure of the molecule, and if so, was there any possible method of showing this? The twenty-two-year-old van't Hoff, already dissatis- fied with these paper pictures, and pondering over the more profound question as to the possible way in which the atoms themselves are held together in the molecule, introduced the conception of molecular structure based on the tetrahedron, and with it gave an impetus to the development of organic chemistry which is felt with added force from day to day. One need but mention the carbohydrates and proteins to realise how much we 79 EMINENT CHEMISTS OF OUR TIME owe the knowledge of the chemistry of these substances to van't Hoff's new branch of the science stereo- chemistry. 1 But stereochemistry was simply a branch development, as it were, of the main inquiry which van't Hoff set about to solve: the kinetics of chemical action. In any chemical reaction we see the beginning, and we see the end of the reaction we seem to know little or nothing of the steps in between. What may they be, and if so, what laws govern them? What of the velocity of chemi- cal reactions and of the various phases of chemical equilibrium? These reflections gave rise to one of the most remark- able books in the whole realm of chemistry van't Hoff's Chemical Dynamics, in which the application of pure mathematics to chemistry finds one of its first and clear- est expressions. And this study culminated in one of the great general- isations in the science the analogy between substances in solution and those in a gaseous form. Van't Hof, Vant hof, Vant hoff, vant hof, van't Hof, van't Hoff so run the pleasant little variations in name from 1600 on. In the middle of the nineteenth century a worthy scion of this well-known Dutch family, accom- panied by his young wife, transferred his medical prac- tise from the little town of Sommelsdijk to the flourishing city of Rotterdam, and in August, 1852, Alida Jacoba van't Hoff gave birth to Jacobus Henricus, Jr., destined to become the master chemical thinker of our generation. Henry's early days alternated between attendance at Kindergarden and pleasant vacations spent with his grandparents at Middleharnis, made famous by Hob- 1 The Frenchman Le Bel, quite independently, and only a month or two after van't Hoff's article appeared in print, advanced prac- tically the same stereometric conception. 80 JACOBUS HENRICUS VAN'T HOFF beam's picture of the place. The kindergarten was followed by the elementary school, and this in turn by the " Hoogere Burgerschool," where Henry achieved a reputation for scholarship, for speculation and for day- dreaming. At the secondary school van't Hoff first received in- struction in chemistry, and as with many another be- ginner, the excitement of cutting and bending glass, preparing, collecting and examining gases, and possible explosions of all kinds, led the youngster to repeat and extend many of the " stunts " at home. The parents and friends were not exactly invited to these exhibitions, for the practical young Dutchman declared that rich feasts should be paid for! And paid for they were. With the money collected, more apparatus was bought, and more bombing expeditions were undertaken. In 1869, at the age of 17, he matriculated at Leyden University, with the following result: mathematics and mechanics, excellent; physical sciences, very good; history, civics and economics, good; languages and literature, fan*; drawing, fair altogether not a bad comparative estimate of his knowledge in later years. But what was he to do now? His own tastes led him to entomology and to literature, neither of which seemed practical enough, however, to the young Dutchman. ; After much family discussion it was decided that Henry proceed immediately to the Delft Polytechnic school, there to equip himself as an engineer. Once a success- ful engineer and a local celebrity it would be easy to re- turn to his first loves. To Delft went young Henry, then, and with a deter- mination to do or die, he at once plunged into the work before him. For the next two years he knew little of companionship and outside pleasures. The work for 81 EMINENT CHEMISTS OF OUR TIME the greater part was distinctly a " grind." He gradu- ated in 1871. In the meantime two things had happened which made him question the desirability of pursuing a technical career. He had spent one of his vacations working in a sugar factory, and found much of this work distinctly monotonous. Was this to be his life work? The thought made him shudder a little. And there was still another factor. Oudeman's chem- istry lectures had made a very deep impression on him. Oudeman was an excellent speculator in his subject, and as we can now readily understand, such a man was precisely the kind of inspiration van't Hoff needed. After finishing his course at Delft, Henry pursuaded his parents to allow him to continue his studies at Leyden, with the particular object of rounding out his mathematical knowledge. He had now quite decided to become a chemist. What, then, had mathematics to do with it mathematics, to prepare for a chemical career in the seventies? At this point one does not know whom to credit more with the instinct of prophecy: his teacher Oudeman, or Henry himself. Of this we are certain: that even at this early age van't Hoff was quite dissatisfied with the purely descriptive state of chemical knowledge. To be encyclopedic only might be bookwormish, but surely not scientific. At the end of a year Leyden grew monotonous. He had gained some mathematics, but little chemistry. To Bonn, then, where reigned the illustrious Kekule, the founder of the theory of the benzene ring, and the speculator of his day. " In Leyden everything was prose the surroundings, the city, the people. In Bonn all was poetry." So wrote van't Hoff many years later. Was this due to Kekule's influence? To some extent, no doubt. But 82 JACOBUS HENRICUS VAN'T HOFF there were other factors. Perhaps a closer examination of the man will enlighten us. Van't Hoff, to be sure, had always been extremely industrious, and had had little leisure or inclination, for that matter to romp with acquaintances; but the time that he did have was largely passed in a world within. He speculated, he dreamt, he romaniticised. Comptes and Whewall and Taine gave him basis for speculation, and Burns, Heine and, above all, Byron, for his romanticism. To the end of his day Byron re- mained his god, and much of van't Hoff' s early life and thought were modelled after that of the poet. Had not Byron declared that Burton's Anatomy of Melancholy was one of the most instructive books that had ever been written? Forthwith does van't Hoff plunge into Burton, with results that are obvious during his student days at least. Does not Byron tell us that Napoleon is the first man in Europe? So says van't Hoff. " This much is certain," writes he ; "if Byron had not had a dog, I would not have had one, and if Alcibiades had not had one, neither of us would have been posses- sors of one. But what if Byron had possessed a don- key? ... Such was Byron's influence that at moments when the differential and integral calculus were not absorbing him and the inner self became dominant, the scientist often aspired to become a poet. But if a poet, it must be, in spirit and expression, as a humble follower of the great master. So we find that at Bonn, when one day, coming into the laboratory, he heard the awful news of the suicide of a fair fellow-worker, he rushed to his study and penned the following: EMINENT CHEMISTS OF OUR TIME Elegy on the Death of a Lady Student at Bonn Thy day is done, young champion of the free ! Thy glory and thy suffering are past, As a weak beauteous flower's, where no tree Can shelter it from cruel Autumn's blast; Which dies in silence lovely to the last; Gone as a day in spring, gone as the dream Of one that wakes no more ; and must it be That thoughtful loneliness passes unseen, Oh! shall thy hapless lot be lost in Lethe's stream! This is not Byron, and yet not so bad for a young chemist, writing in a language not his own. Fortunately for our science, van't Hoff did not receive much encouragement from a fellow poet, and once again he turned his eyes to chemistry and Bonn and Kekule. Here for the first time van't Hoff came into a new world. A celebrated university, situated where there were A blending of all beauties; streams and dells, Fruit, foliage, crag, wood, cornfield, mountain, vine, And chiefless castles breathing stern farewells From gay but leafy walls, where Ruin greenly dwells, with students from every corner of the globe, and with a life so utterly at variance with his experiences hitherto, what wonder that his sensitive nature was filled with love and poetry for the place? " The laboratory is a temple!" writes he to his father; "... and in the lecture room there are to be seen daily about a hundred of our most promising young men, gathered from ten different states, to hear and to see Kekule, whose fame has spread itself over half the world." In the laboratory van't Hoff worked with twelve others at research in organic chemistry, and came into immedi- ate contact with the assistant, Wallach, whose work on the terpenes and camphor was to become epoch-making. 84 JACOBUS HENRICUS VAN'T HOFF Having finished a rather routine piece of work on the synthesis of propionic acid, and having, by the end of about two years, largely outlived his enthusiasm for Bonn, van't Hoff turned his wandering gaze toward Paris. Outside of his wanderlust, just what his object was in going to Paris to study under Wurtz, is not clear. He seems to have done little laboratory work there, but his mind was full of speculations of all sorts, particularly of one which was to find expression shortly. " D etait si tranquille qu'on ne faisait pas grande attention a lui." Such was the opinion of his fellow-students, including Le Bel, through whose head were running ideas very similar to those of van't Hoff's; yet not a word was interchanged between the two regarding their speculations! In the summer of 1874, after a six months' stay in Paris, he returned to Utrecht to complete his doctor's requirements. This degree he attained in December of the same year for another routine research on cyanacetic and malonic acids, and yet four months before he had published an eleven-page pamphlet on The Structure of the Atoms in Space, which was to give him an inter- national reputation! Van't Hoff's practical common sense a nationalistic trait, one might add is nowhere seen to better advan- tage. He might have offered his eleven-page pamphlet for a dissertation, but the probabilities of its acceptance would have been extremely small. Revolutionary ideas are not, as a rule, welcomed in dissertations, and if incorporated, may be thrown out, with such comments as " vague," " fanciful," " unscientific." To explain cases of isomerism which structural formu- las failed to solve, van't Hoff introduced the idea that in such molecules the carbon atom is at the center of a tetrahedran, with its four lines, representing its tetra- 85 EMINENT CHEMISTS OF OUR TIME valency, radiating towards the four points of the tetra- hedran, all four equidistinct from the central carbon point. If at these ends we have four different atoms or groups, we can have at least two such compounds, one the image of the other, and not superpo sable. At first this pamphlet made no impression. It was written in Dutch, which meant at best but a local audi- ence, and it dealt with such novel ideas that most of the scientists of his own land would have dismissed it as a piece of wild imagination, particularly since its author was entirely unknown. To give it a wider circulation van't Hoff translated his work into French under the title of La Chimie dans Vespace. This was all the more necessary since Le Bel, in November, 1874 that * s > some two months after van't Hoff's publication read a paper before the French chemical society, containing much the same views. It cannot be emphasised too strongly at this point that the two had come to practically the same conclusion quite independently of one another. As has happened before, and since that period, the tune was ripe for some such discovery. Over a year passed and nothing happened. Then came from Johannes Wislicenus, already a mighty force in organic chemistry, a letter which is as complimentary to the writer's extraordinary perpicacity as it is of the talent to the man addressed. " Let me tell you," he writes, " that your theoretical development [of the subject] has given me much satisfaction. I see in it not only an exceptionally talented attempt at explaining hitherto insoluble problems, but something which will give a wholly new impetus to our subject, and will thereby become epoch-making. . . . In a short time you will see, I hope, the interest I take in your work by my own re- searches in the field." 86 JACOBUS HENRICUS VANT HOFF The letter concluded with a request to allow Dr. Herrmann, one of Wislecenus's assistants, to translate the work into German, which would then be introduced to the [German] public by a preface from the pen of Wislecenus himself. The translation made its appearance in 1876 under the title of Die Lagerung der Atome in Raume. Like Byron after the publication of Childe Harrold, van't Hoff awoke to find himself famous. But like Byron, again, his fame brought some bitter attacks. Of extreme virulence was one from Hermann Kolbe, the well-known Leipsig professor. " A Dr. van't Hoff" so runs the diatribe "of the Veterinary College, Utrecht [he had in the meantime been appointed to an assist ant ship at this place] appears to have no taste for exact chemical research. He finds it a less arduous task to amount his Pegasus (evidently borrowed from the veterinary College) and to soar to his chemical Parnassus, there to reveal in his La Chimie dans Vespace how he finds the atoms situated in the world's space. " His hallucinations met with but little encourage- ment from the prosaic chemical public. Dr. F. Hermann, assistant at the Agricultural Institute of Heidelberg, therefore undertook to give them further publicity by means of a German edition. ... It is not possible, even cursorily, to criticise this paper, since its fanciful non- sense carefully avoids any basis of fact, and is quite unintelligible to the calm investigator. ..." Kolbe goes on to deplore the times. To think that an unknown chemist should be given a ready ear when he talks of the most difficult of problems, and particu- larly when he treats them with such perfect assurance ! As for Wislicenus, who praised it in an introduction " Herewith Wislicenus makes it clear that he has gone 87 EMINENT CHEMISTS OF OUR TIME over from the camp of the true investigators to that of the speculative philosophers of ominous memory, who are separated by only a thin medium from spiritualism "[!] If I quote Kolbe's criticism at some length it is only to show for the nth tune, no doubt how very often some of the most powerful intellects of the day com- pletely misunderstand the germ of a new idea. And Kolbe was a most representative scientist of his tune. Yet to-day there is not an elementary book in organic or physical chemistry but devotes no inconsiderable portion of its text to stereochemistry ! During the two critical years of 1874 to 76, that is, from the tune of the publication of his pamphlet to the time when the great letter came from the great Wis- lecenus, van't Hoff spent many an anxious and de- spondent hour. As with Huxley and crowds of other despairing young climbers, the Dutchman thought much of emigrating to a distant land Australia, perhaps. This desire was much strengthened by the cold reception he received from know-it-all school directors to pompous college professors, whenever he applied for a position. " He looks rather slovenly. I'm afraid that he'll have lots of trouble with the students." So runs a repre- sentative commentary by an important school official. For the fact that migration did not carry off van't Hoff to a distant land and to an unknown end we have his parents to thank. They constantly counselled patience and persistence. Fortunately, also, these parents of his were comfortably off, and this avoided distractions from his goal, which might otherwise have easily ruined a brilliant career as it has done in in- numerable cases. Patience ! Its first illustration was seen in the f ol- lowing advertisement which appeared in a Utrecht daily newspaper: JACOBUS HENRICUS VAN'T HOFF "Dr. J. H. van't Hoff ( Technology ') will give private lessons in chemistry, physics, etc. Address Mrs. Kortebos, Spoorstrat, C." The pupils came ever so slowly and time hung ever so heavily. This was not an unmixed misfortune, for during his leisure hours further ideas hi organic chem- istry began to crystallise in his head, with results which led to another fruitful volume not so very long after- wards Views regarding Organic Chemistry. Things changed at length probably as a direct result of Wislicenus's letter. In 1876 he was appointed assistant at the Veterinary School hi Utrecht, and in the following year he became lecturer at the University of Amsterdam. In the meantime, in spite of Kolbe's criticism, van't HofPs views on the atoms in space were finding welcome acceptance throughout Europe. His name was on the lips of scientific men everywhere, for his theories had given untold possibilities in the field of experimental chemistry. His introductory lecture, Imagination in Science, was a masterly vindication of his own attitude towards the subject, and incidentally a splendid answer to Kolbe's criticism. The gist of it is contained in the conclusion, quoted from one of his favorite historians, Buckle: " There is a spiritual, a poetic, and for aught we know a spontaneous and uncaused element in the human mind, which ever and anon, suddenly and without warning, gives us a glimpse and a forecast of the future, and urges us to seize truth as it were by anticipation." No wonder, then, that hi 1878, when but 26 years old, he became the faculty's unanimous choice for the chair of chemistry (to which, sad to relate, mineralogy and geology were at first added). 89 EMINENT CHEMISTS OF OUR TIME This was very quickly and very appropriately followed by van't Hoff's marriage to Johanna Francina Mees, the daughter of a Rotterdam merchant. Jenny had been courted from the " Burgerschool " days up. For the next eighteen years van't Hoff remained at Amsterdam. They were his most fruitful years. When in 1896 he was called to Berlin, van't Hoff had become the most renowned physical chemist of his day. The early days of his professorship gave him little leisure. Five lectures per week in organic chemistry, and one each in mineralogy, crystallography, geology and palaentology, together with supervision of the laboratory, which provided for the instruction of graduate students, beginners in chemistry, and medical students all this with but two assistants. Little wonder, indeed, that during these years of exacting teaching and executive duties the name of van't Hoff was quite absent from the pages of the chemical journals. But that, of course, does not mean that his imagination was not as active as ever. It was during these years of much routine, chiefly in the spare moments between supper and bedtime, that the ideas which found their expression in the Etude de Dynamique Chimique the Revolution Chimique^ as it has been called were evolved. This great work appeared in 1884. Speaking to the German chemical society ten years later, van't Hoff told that audience that the origin of these studies was to be traced to his difficulty in explaining certain oxidation processes. For example, oxidation takes place much more slowly with methane than with methyl alcohol. To explain this and other such changes a study of the velocity of reactions became imperative. But the work had an even grander aim, as the preface outlines: " Progress in general in any science passes through two distinct phases. At the beginning all scientific 90 JACOBUS HENRICUS VAN'T HOFF research is of a descriptive or systematic kind. Later it becomes rational or philosophical. It has not been other- wise with chemistry. ... In the second phase of the development, the researches are not limited to collecting and co-ordinating the materials, but these pass to the study of causal relations. The initial interest which they had in a new substance has now disappeared; while the knowledge of its chemical composition and of its properties have a much greater value, becoming the starting-point in the discovery of causal relations. The history of every science consists in the evolution of the descriptive period into the rational period." At first the reception accorded this work suggested that given to his Atoms in Space, that is, it was very quietly ignored. In this case, however, the question of language, or the standing of the author, had nothing to do with it. In 1884 van't Hoff was already a mighty figure, and the French language circulated throughout Europe. The truth was that the I chemists were ill-prepared for any mathematical appli- cations to their subject. This time criticism gave place to silence. However, from far-off Sweden came a reverberating echo. In one of the current journals, the Nordisk Revy, for March 1885, appeared an exhaustive review of van't Hoff's book, in which, among other things, the reviewer had this to say: "Though the author has already achieved prominence by his success in unlocking the secrets of nature, his former accomplishments are put into the shade with the appearance of this work." The reviewer was none other than Svante Arrhenius, then quite unknown, but later a figure to compare with van't Hoff himself and no higher compliment can be paid. As with his earlier work, the Etude is to-day regarded as one of our classics. 91 EMINENT CHEMISTS OF OUR TIME Towards the end of the Etude we already find a clear expression of the relation of osmotic pressure in liquids to the pressure exerted by gases an analogy which soon led to a remarkable elucidation of our knowledge of solution. Sugar and salt are dissolved in water; what happens to the sugar and the salt? In what state are they while in solution? Connecting the preliminary and apparently discon- nected results of Raoult on freezing point depression, and Traube and Pfeffer on osmotic pressure and its measurement, van't Hoff enunciated his most celebrated law : A substance in solution behaves as if it were a gas, occupying a volume equal to the solvent. The year 1887 may be regarded as the most important in the history of physical chemistry. To begin with, the second volume of Ostwald's Lehrbuch der allgemeinen Chemiey the basis for all modern text-books on the subject, made its appearance. Further, the first num- ber of the Zeitschrift filr physikalische Chemie> edited under the joint auspices of Ostwald and van't Hoff, was issued. And last, but not least, van't Hoff's article (revised) on the role of osmotic pressure in the analogy between solutions and gases, and Arrhenius's essay on the dissociation of substances dissolved in water, was published in volume I of the Zeitschrift. As the era of modern chemistry starts with Lavoisier, so the science of physical chemistry starts with the three musketeers, van't Hoff, Arrhenius and Ostwald. In this same year the chair of physical chemistry at Leipzig was offered van't Hoff. Upon this offer coming to the ears of the Amsterdam authorities, attractive counter proposals were immediately advanced. The most alluring of these was that a physics-chemical in- stitute was to be built expressly for him. This was put into effect immediately. 92 JACOBUS HENRICUS VAN'T HOFF During his remaining years in Amsterdam the experi- mental possibilities to which the Etude pointed were rigorously examined by van't Hoff and many students drawn by his fame from all quarters of the globe. Among the latter may be mentioned van Deventer, Spring, Reicher, Arrhenius, Cohen, Bredig, Goldschmidt, Eyk- man, Meyerhoffer, Ewan, and Bancroft (of Cornell) names known wherever physical chemistry flourishes. In 1893 van't Hoff, together with Le Bel, were pre- sented with the Davy Medal of the Royal Society (of London), "in recognition of the introduction of the theory of asymmetric carbon and its use in explaining the constitution of optically active carbon compounds." 1 Such was the progress which the theory had made in the meantime, despite Kolbe. The Germans had made one attempt to capture the great Dutchman, and they were not yet ready to admit defeat. Upon the death of August Kundt, in 1894, the 1 The history of this Davy Medal is of uncommon interest. As a result of innumerable explosions in the English coal mines, with consequent loss of life, a society for preventing such accidents was founded in 1813. One of its first measures was to engage the services of Humphrey Davy, the celebrated chemist. Within a few weeks after his appointment Davy announced the discovery of his wonderful little safety lamp in the following words: " My results have been successful far beyond my expectations. I trust the safe lamp will answer all the objects of the collier. ... I have never received so much pleasure from the result of any of my chemical labors, for I trust the cause of humanity will gain something by it." The colliers were not ungrateful. They presented Davy with a silver plate valued at 1,500 pounds. This plate Davy disposed of in his will as follows: "... I wish her [his wife] to enjoy the use of my plate during her life, and she will leave it to my brother in case he survives her, and if to any child of his who may be capable of using it; but if he is not in a situation to use or to enjoy it then I wish it to be melted and given to the Royal Society to provide a medal to be given annually for the most important discovery in Chemistry made in Europe or Anglo-America. ..." 8 93 EMINENT CHEMISTS OF OUR TIME Berlin faculty unanimously suggested van't Hoff's name for the chair of experimental physics. Max Planck, the faculty's representative, was sent on a special mission to Amsterdam. Althoff, the representa- tive in the Prussian Ministry of Education, sent van't Hoff an additional message urging him to come to Berlin and talk matters over. Finally, when some hesitation still prevailed, Emil Fischer was commissioned to use his good offices. Van't Hoff, Jr., and van't Hoff, Sr., weighed the pros and cons carefully. The offer was an unusual one, and the honor extraordinary, but the duties of an active pro- fessor at Berlin were not light, and here in Amsterdam the authorities, ever afraid to lose their gifted country- man, were ready at the first sign to lighten his burdens, or increase his equipment. So van't Hoff, with papa's advice, once again said nay. But Berlin wanted van't Hoff. Was it a question of too many hours of university teaching? Very well, then; this will be cut down to an absurd minimum. Since he is to hold a professorship, some lectures at the University must be delivered, but unless otherwise desired, these lectures need not exceed one per week. The rest of the tune shall be van't Hoff's absolutely. Further, a private laboratory, equipped for any type of research van't Hoff shall elect, will be provided. Need we wonder that he fell victim? " When for the past twenty-years, year in and year out, one teaches that potassium permanganate is an oxidising agent, one gets a little tired," was van't Hoff's comment. "... Of course, I have a very good position here in Amster- dam that cannot be denied. But there is a difference between good and good. And when invitations are always rejected, there comes a tune when no more invitations are received." 94 JACOBUS HENRICUS VAN'T HOFF The German universities get the best brains their land can offer, and when better brains still are found beyond their border, the most alluring offers are sent forth. Thus it happened that at a later date attractions were held out to Arrhenius, and even our own Richards had difficulty in freeing himself from the Gottingen clutches. If only the Anglo-Saxons would follow suit here! If only in leaving the whey of German university training they would be careful to retain any cream! What a joy it would be to see Manchester scrambling for a Noyes, or California for a Soddy! It goes without saying that van't Hoff's migration met with criticism in Holland. He was pictured as un- patriotic, and as being ready to grab all he could get, never being satisfied with what he had. Even the Dutch Punch did not spare him. Picturing van't Hoff in conversation with a fish, the following caricatures were presented : (1) Dr. v't H: Fish fish in the sea, bring me a cap and gown. Fish: Here it is. (2) Dr. v't H : Fish fish hi the sea, bring me a labor- atory. Fish: Here it is. (3) Dr. v't H: Fish fish in the sea, bring me an Order of the Crown. Fish : Here it is. (4) Dr. v't H: Fish fish in the sea- Fish: Still not enough? Adieu! Writing to his friend Cohen from Charlottenburg (on the outskirts of Berlin) on April 23, 1896, van't Hoff ,says: " This is quite a new life, and I look forward with hope to the future. . . . Our apartment here [Uhland- strasse 39] is excellent, and the situation all that can be desired half within, and half without the town. A 95 EMINENT CHEMISTS OF OUR TIME pleasant walk takes us to Grunenwald [a forest nearby], from where we can return by train if desired, and the station is quite near the house. " I now find much more time to be with my family, and this has particular attractions amidst strange sur- roundings. The children all go to school. Everyone of them, with the exception of Goof [the youngest] has cried at one time or another because things were not quite what they were before. But children accli- matize themselves quickly enough provided they are healthy, and the air here seems excellent. "I have attended two meetings of the Academy, which seem quite attractive under the stimulus of a respectable cup of coffee. On Wednesday I shall give my first lecture (one per week) as part of my duties as ordentlicher honor ar professor. "For the time being my laboratory consists of an apartment, which I have rented near our home, and this I shall equip with Meyerhoffer's help [Meyerhoffer was van't Hoff's favorite assistant in Amsterdam whom he had induced to come to Berlin], " We intend to begin research work on the Stassfu salt deposits. . . . The foundation for everything has been laid, and so far as I can see everything looks bright and cheerful. . . . " My ever well-disposed wife and I pay quite a num- ber of visits to the celebrities, whom I do not always know how to entertain, and whom I am forever mis- taking for other folks. Three dinners are in pros- pect. ... The task which van't Hoff now set himself was to make an exhaustive investigation of the potash deposits in Stassfurt, Germany. When we remember that until the outbreak of the world war the entire world was practically dependent for its potash to be used as a 96 JACOBUS HENRICUS VAN'T HOFF constituent in fertilisers upon these Stassfurt deposits, the value of any research connected with them can well be understood. Of the substances present, the mineral, carnallite, is by far the most important. The question which van't Hoff first asked himself, and one which became the keynote to all his subsequent work, was: "Carnallite being a compound of magnesium and potassium chlor- ides and water, what arises when these three sub- stances are brought together in different proportions, at different temperatures, and the escape of the water is prevented?" Between 1896 and 1906 more than fifty papers were published on this and related subjects by van't Hoff and collaborators, of whom Meyerhoffer stands out pre- eminently. The work is of the most complicated kind, and no one has yet been found who has been bold enough to attempt a critical appraisal. This much seems certain: that while the work is a splendid application to industry of the phase rule by Willard Gibbs, the Yale professor, it is overshadowed in originality by van't Hofif's earlier contributions. In 1906 van't Hoff turned his attention to one of the most fascinating problems in biochemistry: the nature of enzymes those substances, present in all cells, which bring about the chemical changes in the organism so essential to life. The one or two papers on this subject, which appeared immediately prior to his last illness, were full of pregnant possibilities, and showed the master at his best. In 1900 van't Hoff was elected president of the German chemical society; and in the following year he became the first recipient of the Nobel Prize in chemistry, Rontgen receiving the physics prize, and Behring, the one hi medicine. In 1909 the Prussian Academy of 97 EMINENT CHEMISTS OF OUR TIME Science presented him with the Helmholtz medal, the highest honor which they could bestow. Van't Hoff, never robust, had been a sufferer of tuberculosis for a number of years. The dread disease took hold of him with particular virulence towards the end of 1910, and it was soon apparent that he could not hope to hold out much longer. On March i, 1911, at the age of 59, the greatest Dutchman of our tunes breathed his last. With his beloved Byron can we say that here was one " too soon returned to earth." When fame had come a-plenty, van't Hoff was much in demand at scientific gatherings. Such travelling as attendance at these meetings made necessary was under- taken with little hardship after his singularly fortunate Berlin appointment, and he loved to mingle with his scientific confreres. In 1890 he attended the British Association meeting at Leeds, and took an active part in the discussion on solution (see the article on Ramsay). In 1893 he delivered an address on La Force osmotique before the Sociele chimique de Paris, which probably explains why hi the following year he was nominated for the Legion of Honor on the ground of his " remarquables travaux sur la chimie dans 1'espace" ! In 1894 he addressed the Deutschen chemischen Gesellschaft on " Wie die Theorie der Losungen entstand." 1 1 The late Prof. H. C. Jones, who was pursuing graduate studies in Germany at the time, and who was present at this lecture, thus describes the event: " There sat in the front row Helmholtz, Ost- wald, Emil Fischer, and a number of other men of science were present, whose names have become household words. These included Landolt, Kossel, Jahn, Tiemann, Will, Witt, and many others. " The entrance of Helmholtz into the lecture room made an im- pression that will not be forgotten. Helmholz had attended the 98 JACOBUS HENRICUS VAN'T HOFF In 1898 van't Hoff, as the triple delegate of the Univ. of Berlin, of the Academy, and of the Chemical Society, undertook a trip to Stockholm to attend a Berzelius celebration. To honor the memory of the immortal Swedish chemist was doubtless his desire, but a still greater incentive for this journey was the opportunity it afforded to be with his friend Arrhenius. Three years later we find him on his way to the United States to attend the tenth anniversary of the founding of the University of Chicago (see addendum); and before the year is out he is to be found hi London, in the Royal Institution, holding forth " in perfect English syntax, with here and there a modification of the vowels which indicated that the language was not his native World's Fair in Chicago, and on his return home, when disem- barking at Bremen, had slipped and fallen down the stairway of the ship. He, as is well known, ruptured a blood vessel on the head, which at the time nearly caused his death from loss of blood. . . . When Helmholtz appeared at the top of the lecture room, Emil Fischer ran and assisted him down the steps to a seat in the front row of the hall; the greatest physicist of the day aided by the most active organic chemist of that period. " The object in inviting Van't Hoff to lecture in Berlin at that time, was to see and hear him with the possibility of calling him to that great university. His fame had already spread, and the real greatness of the man was even then beginning to be pretty fully realized. . . . " This was the first time I had ever seen Van't Hoff. There arose to speak a slight figure of scarcely average height, with long, rather coarse hair, and with an extremely modest demeanor. This, as is well known to those who knew Van't Hoff at all closely, was one of his most striking characteristics. The speaker at first seemed a little nervous, due no doubt in part to the character of the audience he was facing, and in part to the fact that he probably suspected the motive in asking him to lecture in Berlin just at that time. . . . Van't Hoff had not proceeded far with the lecture, when any initial nervousness entirely disappeared, and his manner of presentation made a deep and lasting impression upon his audience." 99 EMINENT CHEMISTS OF OUR TIME tongue." The theme was the life and labors of Raoult, the eminent French physicist, who had but recently died, and whose work was so indissolubly bound with that of van't Hoff. The concluding words of this lecture apply as much to van't Hoff as to Raoult: "Yet his (Raoulfs) character may be read hi his papers: activity, patience, tenacity to an extreme degree hi pursuing an aim, having an eye as much for detail as for vaster and vaster horizens, absolute independence of mind, power of criticising or of admitting without passion the views of others as well as his own, and of testing both with the same calm conviction that the last word must rest with experiment; this is what we read hi every page and what the whole chemical world may know." Two years later (hi 1903) he is hi England once more this time in Manchester, in the city where once reigned a John Dalton and a James Prescott Joule, of whom Manchester ought to be far prouder than she is (which is saying no more of Manchester than what might be said of many another English or American city). One hundred years had passed since Dalton had brought forward his Atomic Theory, and the university of his native city now celebrated the event in becoming fashion. What the university authorities thought of van't Hoff may still be gauged to-day by anyone who enters the chemical laboratory of the university. At its entrance is a tablet with this enscription: "This stone was laid by Professor J. H. van't Hoff, 2oth May, 1903, in commemoration of the centenary of Dalton's Atomic Theory." In the following year we find him in Munich, sent [there to represent the chemical society at the celebration of Baeyer's seventieth birthday. Van't Hoff had a very soft spot for the great Baeyer, the master of the chemistry of indigo and countless other organic substances, who, zoo JACOBUS HENRICUS VAN'T HOFF as far back as 1875, had declared of the Atoms in Space, " Da 1st wirklich mal wieder ein neuer guter Gedanke in unsere Wissenschaft gekommen, der reiche Fruchte tragen wird." A journey to Vienna hi 1906, to attend a conference of Austrian engineers and architects, who strange to relate ! were eager to hear van't Hoff on the subject of thermochemistry, gave him unusual pleasure. " Vi- enna that was delightful," he writes; "I shall never forget those days. Profs. Klaudy and von Juptner had arranged for everything, and every hour was accounted for. It was only with the greatest difficulty that I could escape sometimes. I was really amazed at the things I could still do at my age. Don't ask me what I have seen. I have seen everyone except the Kaiser, and have done everything except rest. But it was all so lovely." That same year he and his wife were in Italy to witness an eruption of Vesuvius. Whatever enjoyment the two got out of this trip was more than offset by van't Hoff's disease, which at this stage gripped him with added force. We have seen how in early life van't Hoff was the poet and romanticist. In later years poetry was all but for- gotten. His thoughts were with his chemistry every- where, and at all times. Even music served but to concentrate his mind upon a problem, for he has told us that " good music makes it very pleasant to think of other things " " other things " being, perhaps, the velocity of some reaction. Towards the end of his life, when doctors' orders forbade mental effort, he branched out into novel reading, and passed time with Turgenieff and Zola the latter, in particular, a strange antithesis to the Byron of his youth. Van't Hoff had never been robust, and ceaseless mental activity added to the uncertain elements in his IOI EMINENT CHEMISTS OF OUR TIME state of health. 1 Hayfever was a regular yearly visitor, and in later years tuberculosis added to his afflictions. 2 Van't Hoff's wife and four children, Johanna Francina (b. 1880) (who married privat-docent Ulrich Behn in 1905), Aleida Jacoba (b. 1882) (who married Dr. Charles W. Snyder, of Baltimore), Jacobus Hendricus (b. 1883), and Go very Jacob (b. 1889) survive him. Addendum van't Hoff in America On the occasion of its tenth anniversary, the Uni- versity of Chicago invited some distinguished foreign scholars to attend its celebration. Among these was van't Hoff. Whilst on his journey van't Hoff kept a brief diary which has since found its way into Ernest Cohen's life of the great Dutch chemist. No sooner were the necessary arrangements com- pleted with Nef , representing the University of Chicago, than further invitations began to pour in from the American Chemical Society, from Yale, from Richards at Harvard, from Bancroft at Cornell, from Loeb at Wood's Hole, etc. With his wife by his side, and with a dose of sodium cyanide hi his pocket, to be used in case of accident a typical European custom van't Hoff set sail from Rotterdam on May 21, 1901. Being a Dutch celebrity, i " Van't Hoff ... not only worked under high tension, but he seemed to live under high tension. When one saw him on the street he moved as if on rubber, and this kind of living would, in time, of necessity react upon the nervous system." Prof. Harry C. Jones. 2 " van't Hoff, as is well known [to whom?] contracted tubercu- losis, probably while studying an eruption of Vesuvius. He thought that the dust lacerated his throat and lungs, and that the tubercle bacillus then began its work." Prof. H. C. Jones. 102 JACOBUS HENRICUS VAN'T HOFF the directors of the Holland-American Line set aside a stateroom for his use, and at table he sat with the captain on one side of him and the Dutch Consul to St. Paul on the other. The voyage, aside from a day of rough weather, was, on the whole, a pleasant one. Professor Webster Wells, of Boston, and Dr. Pettijohn, of Chicago, whom he met on board, proved agreeable companions. During the spare moments when talk and play did not occupy him, van't Hoff busied himself with Loeb's work. After landing in New York, where his pockets were searched by a custom-house official as though he were a pickpocket (!), van't Hoff registered at the Savoy Hotel. Here troubles soon began. The taxi-man proved ex- orbitant. The wash basin hi his room had unexpected possibilities. The shades simply could not be moved, as though defiant of European authority. And the trunk, without which outdoor life was not to be thought of, simply would not show up. In good time things righteu themselves somewhat. With the arrival of the trunk a brief stroll was under- taken. Everything was greeted with open-mouthed astonishment. Much was found that was beautiful; much that was ugly; but everywhere something very distinctively American was encountered. Upon his return, cards from Professor Chandler, from his son- in-law, Pellew, and from a reporter of the New York Tribune^ together with an invitation to the Century Club, awaited him. This was evidently the beginning of American hospitality. At luncheon there was a welcome introduction to ice- water an unknown luxury in Europe. After the mid- day meal, Miss Maltby, of Barnard, whom van't Hoff had met in Gottingen, called on him and his wife, and the trio started out on a stroll through Central Park and 103 EMINENT CHEMISTS OF OUR TIME the Zoo, thence by bus to the " glorious " Hudson and Grant's Tomb, and finally to Barnard and the girls for supper. The following day visits to Hale, to Chandler and to Pellew were planned. Brooklyn proved too complicated a center, and Hale could not be located. However, a sight of Brooklyn Bridge partially repaid his disappoint- ment, for this structure aroused much admiration from the artistic scientist. The homes of Chandler and Pellew, " with their well-dressed ladies," were easier to find. Not being expected in Chicago for some days, van't Hoff decided to visit some places of interest in this country. The first to be selected was Baltimore, with its Ira Remsen and Johns Hopkins. The country, as viewed from a Pullman, did not excite him much. One feature was the large posters along the road, announcing such items as " Baker's 5c Cigars, Generously Good," or " Omega Oil For Sore Feet, Stops Pain, For Head- aches, For Everything." That, at least, was America with a vengeance! Passing into Philadelphia over the Delaware recalled the story of the famous crossing and the chain of dramatic events that followed it. Baltimore was much more after his own heart. There was none of that breathless living so characteristic of the Empire City. Here people lived more on the style of the Rotterdammers and Amsterdammers. At the University he met his old pupil, Harry C. Jones, whose open-hearted laughter, with his "all right" and "first-rate" and "that's it" won van't Hofif completely. Here he was shown the first of the series of classical researches on osmotic pressure, so intimately associated with the name of Morse. The greeting by President Remsen and the Faculty in the Senate House was most cordial. "Really 104 JACOBUS HENRICUS VAN'T HOFF great " was a phrase used, and van't Hoff felt satisfied. The lunch at Remsen's which followed it, however, was too exclusively American; particularly the grape-fruit, which van't Hoff had not, as yet, cultivated a taste for. On to Washington! More south! More negroes!! Fans!!! Here the trusty Baedeker did yeoman service whether at the Capitol, or at Howard University (a uni- versity for negroes I), or at the Geological Survey, or at the Smithsonian Institution, or at Mount Vernon. There was much to admire. And Day and Clarke and Hillebrandt, of all of whom he had heard much, he was glad to meet. Over the Lehigh Valley to Mauch Chunk, the " Ameri- can Switzerland, 1 ' with its immense coal-fields, and thence to Ithaca. Here some delightful hours were spent with Bancroft and his wife. An introduction to President Schurman gave occasion for a discussion of the influence of the money-kings on the development of American universities. This was apropos of the dis- missal of a professor who professed leanings towards socialism. Their next stop was in Buffalo, where the Pan-American Exposition and the grand Niagara Falls were visited. From Buffalo van't Hoff proceeded direct to Chicago. The Pullman arrangements were an unpleasant surprise to him. He recalled how traveling from Paris to Strass- burg each passenger had his own little room with his own wash-stand. But these common sleeping quarters, stiflingly hot and uncomfortable, with one wash-stand for all! At Chicago Nef had undertaken to look after his com- fort, and the result was everything that could be desired. His suite at the Hotel Windemere was ducal in pre- tentiousness. 105 EMINENT CHEMISTS OF OUR TIME The first part of the celebration consisted of a reception tendered by Mr. Rockefeller. Here he made the ac- quaintance of Stieglitz and Alexander Smith. In the afternoon van't Hoff delivered the first of his promised addresses, and this duly made its appearance in Science. Later on, Nef took him to a baseball game which was to be played between Chicago and Michigan, and here, for the first time, van't Hoff really understood just what baseball is. It would seem that while in Washington he had one day watched a steamer crowded with lively young girls depart for a baseball game. At that time our learned professor was of the opinion that baseball was some sort of a dance ! In the evening the president tendered a dinner to his guests. Van't Hoff was seated between M. Cambon, the French Ambassador, and Professor Goodwin, of Harvard. Goodwin considered van't "Hoff's speech on the occasion " American Ideals " the best, because it was the shortest! Rockefeller's presence made wine or beer out of the question. Following this came the general reception, which was most noteworthy for the immense crowd that had gathered there. Van't Hoff retired to a quiet corner with Alexander Smith, " an extraordinary tall col- league." The following day June 18 began with the laying of the foundation stone. The heat was terrific, and poor van't Hoff fell quite asleep during the long-drawn-out speeches. Then came the awarding of degrees. All the honorary recipients were there, with the exception of the Russian, who had got his dates confused because of sticking too close to his Russian Calendar ! Fully one half of the students who received degrees were girls. This was an excellent augury for the future, 106 JACOBUS HENRICUS VAN'T HOFF thought van't Hoff, and the thought he conveyed to an acquaintance sitting near-by. This man explained the University's point of view by saying that the authorities did not greatly encourage the girl graduates to seek positions, but did like to see these same girls marry rich men. Why? Because it would then be the duty of these girls to interest their rich husbands in the needs of the University. Was the man serious? van't Hoff was among a few to receive the honorary degree of Doctor of Laws. At i P.M. came the alumni dinner, and van't Hoff was honored by being seated next to Rockefeller. Very little conversation was carried on with the oil magnate, because this gentleman seemed much too preoccupied with his coming speech. When Rockefeller's turn did come, he commenced with a story about a negro who was asked what he thought of Jesus, to which the negro replied, " I have nothing against Him." With this, Rockefeller turned to the public and said, "I have nothing against you." Van't Hoff does not tell us how the millionaire further developed his speech. Again not a drop of alcohol on the table! Again Rockefeller's influence I The next four or five days were mainly occupied with the preparation and deliverance of the lectures since published and translated into English by Alexander Smith. On the 24th of June van't Hoff departed for Cam- bridge. At Boston he was met by Richards, who had provided for his comfort as liberally as had Nef at Chicago. On the 26th, which was the day of Harvard's Com- mencement, van't Hoff was presented for his honorary degree as " the greatest living physical chemist," a statement which was received with much applause. The 107 EMINENT CHEMISTS OF OUR TIME lunch at Memorial Hall which followed was chiefly memorable because of Roosevelt's presence. The well- advertised teeth showed prominently. The evening was spent at the homes of Richards and Miinsterberg. The following day, with Jackson and Richards as guides, Boston's sights were carefully inspected. In the evening he was the chief guest at a dinner which included Presi- dent Eliot, Richards, Jackson, Pickering, Trowbridge, Hill, Michael and Bancroft. Gibbs and Crafts sent regrets. Van't Hoff was seated next to Eliot, who dis- cussed with him the possibility of losing Richards, at that tune considered as a probable candidate for the chair of chemistry at Gb'ttingen an unusual distinction for an American. Van't Hoff took his departure from this country highly impressed with all that he had seen. He prophesied that within fifty years American universities would seriously rival those in Europe. It is but nineteen years since he has been here, but his prophecy has already come true. References Cohen's life of his great master (i) contains most of the available biographical material. For references to atoms hi space, see 2, 3 and 4; for organic chemistry, 5; chemical dynamics, 6 and 7; theory of solution, 8; Stassfurt deposits, 9. 1. Ernst Cohen: Jacobus Henricus Van't Hoff: Sein Leben und Wirken (Akademische Verlagsgessellschaft, Leipzig. 1912). 2. J. H. van't Hoff: The Arrangement of Atoms in Space (Long- mans, Green and Co. 1898). 3. J. H. van't Hoff: Chemistry in Space (Clarendon Press, Oxford. 1891). 4. J. H. van't Hoff: Stereochemistry. Encycl. Britannica, 25, 890 (1911)- 5. J. H. van't Hoff: Ansichten u'ber die organische Chemie (Vieweg und Sohn, Braunschweig. 1881). 108 JACOBUS HENRICUS VAN'T HOFF 6. J. H. van't Hoff: Studies in Chemical Dynamics (Chemical Publishing Co., Easton, Pa. 1896). 7. J. H. van't Hoff : Lectures on Theoretical and Physical Chemistry. Part i. Chemical Dynamics. Part 2. Chemical Statics. Part 3. Relation Between Properties and Composition (Edwin Arnold, London. 1899). 8. H. C. Jones: The Modern Theory of Solution (Memoirs by Pfeffer, van't Hoff, Arrhenius and Raoult) (Harper Brothers. 1899). 9. J. H. van't Hoff: Physical Chemistry in the Service of the Sciences (English version by Alexander Smith) (University of Chicago Press, Chicago. 1903). 109 SVANTE ARRHENIUS JNIUS'S fame rests secure on his The- ory of Electrolytic Dissociation, which postu- lates that those substances which, when dissolved in water or any other solvent, are good conductors of electricity, are also those substances which, in solution, largely decompose, or dissociate, into atoms, or groups of atoms, carrying powerful electric charges (the so-called " ions "). The theory was a direct outcome of van't Hoff's osmotic pressure studies, and its effect on the development of every phase of chemistry has been incalculable. That it is as sound in principle as Dalton's Atomic Theory or Mendeleeff's Periodic Law can hardly be doubted, for it, like the others, has helped to clear up many mysteries and to pave the way for many new discoveries. Its services have extended beyond chemistry and invaded the realms of the physi- ologist, the botanist, the zoologist and the medical man. One may mention the insight it gives us into the mechan- ism by which the blood maintains its remarkable neutrality, and the light it has shed upon various phases of cellular activity. Arrhenius' later contributions to bacteriology and astronomy stamp him as one of the most versatile, as well as one of the most extraordinary men of our age. Svante Arrhenius was born in Wyk, near Upsala, Sweden, on February 19, 1859. His father and mother (nee Thumburg) traced their descent back to many a generation. Soon after Arrhenius's birth his parents moved to Upsala, Sweden, and there young Svante received his in EMINENT CHEMISTS OF OUR TIME public and high-school education, matriculating at 17 with an exceptionally fine record in mathematics, physics and biology three subjects, in which his genius was to find splendid scope. For the next five years he pursued his studies at the University of Upsala, specializing in mathematics, physics, and to some extent in chemistry. In this last subject he had Cleve for professor, and Cleve's lectures on organic chemistry gave Arrhenius food for thought. The simplest formula for cane sugar, said Cleve, was Ci 2 H 2 2On; the strong probabilities were that the actual formula was a multiple of this, but there was no known way of finding out. Why not? thought Arrhenius, to whom things " unknowable " presented an irresistible fascination. And he forthwith set out to solve the prob- lem of determining the molecular weight of the sugar by some electrical means, electricity being the key to all difficulties. All Arrhenius's attempts ended in failure. In the meantime, Raoult, the professor at Grenoble, France, had solved the mystery by his freezing-point determina- tions, but many days were to pass before the voice from Grenoble would reach Upsala. Arrhenius's attempts led him to investigate the con- ductivity of solutions (with respect to the electric cur- rent), and by one of those happy strokes which of ten decide a man's fate or career, he chose dilute rather than concentrated solutions. These experiments were carried out in Stockholm during 1881-84, for Upsala offered few favorable facili- ties. Edlung, the professor of physics, and the great authority on electricity, dissuaded Arrhenius from all chemical pursuits, possibly because he himself knew little chemistry. Arrhenius thanked him for his advice and went his own way; but Edlung undoubtedly gave 112 SVANTE ARRHENIUS him that foundation in the science of electricity without which his great discovery would have been impossible. Our young experimenter had not groped his way many miles before he formed the opinion that in dilute solutions there was a complete dissociation, or cleavage of the molecules. These were startlingly heterodox views. Did this young physicist assert that when common salt (the chemical name for which is sodium chloride) is dis- solved in water, the salt dissociates into its components sodium and chlorine? Absurd! Sodium is a poisonous white metal, which violently attacks water as soon as it comes in contact with it; chlorine is a yellow-colored, suffocating gas, only too well known to the present generation. But neither sodium, nor chlorine, nor anything like these two elements makes its appearance when salt is dissolved in water. Answered Arrhenius, meekly, but nevertheless with conviction, the chlorine and the sodium that are freed ' are not freed as chlorine and sodium atoms, but as j chlorine and sodium " ions " (borrowing a word corned \ by Faraday), which are atoms (and sometimes groups [ of atoms) carrying powerful electric charges; these I electric charges powerfully modify the properties of the ;' elements. What, then, does an electric current do when it passes t through the solution? How, under these circumstances, \ do you explain the formation of hydrogen and chlorine ? at the two poles? That's simple, said the twenty-odd year old Swede. The current does not dissociate the salt the water does that; the electric current merely directs the path of the ' ions, sending the sodium ions to the cathode, and the chlorine ions to the anode. There the opposite electrical charges neutralise one another and sodium and chlorine ( EMINENT CHEMISTS OF OUR TIME atoms remain. The sodium atom is no sooner liberated than it attacks the water, decomposes it, forms caustic soda, and liberates hydrogen; so that the net result of the operation is to form caustic soda and to liberate the two gases hydrogen and chlorine. The explanation was simple enough and fitted the facts remarkably well, but Arrhenius had disadvantages to contend against. He was a mere boy and quite unknown, and his professors were men of renown, who, like most men beyond a certain age, unlearn with diffi- culty, and adopt new ideas only when painful necessity makes any other course impossible. But at this lime there was no such necessity. Arrhenius was a candi- date for the doctor's degree, and without counting the consequences, he incorporated many of these heteredox views in his thesis with the elaborate title : Recherches sur la conductibilite galvanique des electrolytes (i) conductibilite galvanique des solutions aqueous extremementdiluees; (2) theorie chimique des electro- lytes. No wonder the professors were up in arms. What right had a candidate for a doctor's degree to express views so diametrically opposed to those held by the authorities? At this time Arrhenius had not yet made the acquaint- ance of van't Hoff, otherwise that immortal Dutchman, no less immortal because of his good, hard common- sense, might have advised his colleague in Sweden to present a stereotyped research for the Ph.D. and reserve his more valuable work for another occasion just as van't Hoff himself had done several years before in Utrecht. Fortunately for Arrhenius he began to scent difficul- ties just in the nick of time. Instead, therefore, of saying that in a dilute solution there was total dissocia- 114 SVANTE ARRHENIUS tion, he declared himself in favor of the view that in solution salts consist of two different kinds of molecules, the inactive " this expression did not look danger- ous " and the active, the latter only conducting elec- tricity. In a moment of happy inspiration, Arrhenius added that the active molecules are in a state described by Clausius. Now Clausius was the physicist of the physicists of his time whom the Stockholm School simply venerated, and truly enough Clausius had expressed views closely resembling Arrhenius's, though not carried to so logical a conclusion. Said Arrhenius to an American scientific gathering not many years ago : " He [Clausius] was a great authority, therefore it could not be regarded as unwise to share his ideas." A careful review of Berthellot's thermo-chemical studies led Arrhenius to the view that the strongest acids were also the best conductors of electricity. "The next step was also quite clear: the active molecules, which are active in regard to electricity, are ! also active in regard to chemical properties, and that was | the great step. ... I got that idea on the night of the 1 7th of May in the year 1883, and I could not | sleep that night until I had worked through the whole problem." Everything followed from this: the constant amount | of heat formed when strong acids and strong bases react (due to the formation of undissociated water in every 'reaction of this kind); the reaction of electrolytes (sub- : stances which conduct electricity) as being due to the reaction of the ions first formed ; etc. " I had deduced a rather great number of different properties which had not been explained before; but I must say that this circumstance made no very great impression upon my professor at Upsala." "5 EMINENT CHEMISTS OF OUR TIME "I came to my professor, Cleve, whom I admire very much, and I said, ' I have a new theory of elec- trical conductivity as a cause of chemical reactions.' He said, ' This is very interesting,' and then said, * Goodbye ! ' He explained to me later [when Arrhenius was presented with the Nobel prize] that he knew very well that there are so many different theories formed, and that they are all almost certain to be wrong, for after a short tune they disappear; and therefore by using the statistical manner of forming his ideas he concluded that my theory also would not exist long" [!] Newlands' Law of Octaves anticipated the Periodic Law, but the ridicule that was heaped upon it by mem- bers of the English chemical society completely dis- couraged him. Not so Arrhenius. Having failed in his own country, he turned to foreign lands and wrote to Clausius, Thomson, and again by a happy inspiration Ostwald. The first two replied in a friendly tone: "They were glad to make my acquaintance, but not much more." Ostwald, however, was deeply impressed. He had worked much on the chemical activity of acids, and now, with the help of Arrhenius's dissertation, he investigated their electrical activity, and found that the two ran proportionally. In later years, when Arrhenius's theory had well nigh assumed the majesty of a law, Ostwald was fond of relating how he got, on the same day, the Swede's dis- sertation, a toothache and a nice daughter. " That was too much for one day," was Arrhenius's comment; " the worst was the dissertation, for the others developed quite normally." " The worst was the dissertation." Quite true. The struggle was but in its infancy. 116 SVANTE ARRHENIUS He had made, however, one all-powerful adherent. In Ostwald he found a man who is the expounder par excellence. What Huxley was to Darwin, Ostwald became to Arrhenius; and Ostwald is a first-class scientist, a gifted writer and a fighter to be feared further unmistakable resemblances to the great Huxley of the Victorian period. The battle of the "ions" in the eighties and nineties waxed just as hot as the battles over the descent of man in the sixties and the seventies. The analogy may be carried a step further. In Darwin's days the battle was no less severe, though such choice spirits as Malthus and Lyell had anticipated, and to a certain extent paved the way for Darwin's work. So prior to Arrhenius's day the rumblings of a storm were announced by Valson and Raoult and Gay- Lussac and Williamson and Clausius. Even Lord Rayleigh, as president of the British Association for the Advancement of Science in 1884 said : "... from the further study of electrolysis we may expect to gain improved views as to the nature of chemical reactions, and of the forces concerned in bringing them about. ... I cannot help thinking that the next great advance, of which we have already seen some foreshadowing, will come on this side." What could be plainer? But Rayleigh, renowned physicist that he was, spoke as a voice in the wilderness. The multitude could not and would not see. Ostwald came to see Arrhenius in Stockholm to talk matters over, and, incidentally, to give a certain amount of prestige to the young doctor. In Upsala Ostwald saw Cleve who, taking up a water solution, said to the Riga professor, " And you also are a believer in these little sodium atoms swimming around? " to which Ostwald replied that he thought there was some truth in that 117 EMINENT CHEMISTS OF OUR TIME idea. " Cleve threw a look at me which clearly showed that he didn't think much of my chemical knowledge." The university authorities granted Arrhenius the doctor's degree, but their commendation " non sine laude approbateur " showed that the dissertation had aroused no great enthusiasm in their breasts. Arrhenius now decided to do what many an American prodigy has been forced to do : he decided to leave his country and fight for recognition in foreign lands. He knew well enough that should he come back crowned by the approval of the great masters of Europe, the former scoffers would become his loudest admirers. So he made arrangements to accept Ostwald's hospitality in Riga and pursue further investigations at the poly- technic school there. Both met later at the Naturforscher-versammlung (similar to our Association for the Advancement of Science) in Magdeburg, with the object of proceeding to Riga together after the conclusion of that gathering. But the illness of Arrhenius's father temporarily upset all plans, and Arrhenius returned home. His father died in the spring of 1885, and about a year later Arrhenius set out for Riga, materially eased by a stipend which he had received from the Swedish Academy at the earnest solicitation of his teacher, Edlung. Ostwald had set aside part of his own private labora- tory for Arrhenius's use, and though the two did not work together, they had ample opportunity for ultimate dis- cussion, and this led to a friendship which grows stronger day by day. After spending the winter, spring and summer with Ostwald, Arrhenius, true to his undertaking, left for Wiirzburg to study under Kohlrausch. Here he came upon van't Hoff's celebrated memoir on osmotic pres- 118 SVANTE ARRHENIUS sure, in which Raoult's work was extensively discussed. It now became quite clear to Arrhenius that all electro- lytes consist of the equivalent of at least two molecules and not one that a molecule of common salt (sodium chloride) when dissolved in water, produces the effect of two molecules, due to the formation of the two ions, sodium and chlorine, each of which behaves as if it were a molecule. These conclusions now rested upon chemical, electrical and thermodynamic evidence. 1 The above explanation made clear certain anomalous results which van't Hoff obtained in his experiments on osmotic pressure. In some instances the osmotic pres- sure was twice as great as what might have been ex- pected from theoretical considerations. This " double bombardment " of the molecules, for which vanJt Hoff made allowances in a mathematical equation to express the reaction, was now seen to be due to the bombardment of ions. For every molecule two ions were formed, and each ion behaved as a molecule. This led to a correspondence which culminated in a rare friendship between the two foremost physical chemists of the age. Writing to van't Hoff from Wurzburg in 1887, Arrhen- ius makes inquiries as to the possibilities of working in his laboratory in Amsterdam. The prompt reply has more than a cordial ring. Van't Hoff advises the Swed- ish scientist to come somewhat before the vacation is completely over " so that I may give my entire atten- tion to your visit." 1 Prof. Jacques Loeb informs me that van't Hoff's first paper on osmotic pressure was submitted to the Swedish Academy, and the secretary of that body passed it on to Arrhenius for an expression of opinion. In van't Hoff's paper Arrhenius found the data which supplied the missing links to his theory of electrolytic dissociation. IIQ EMINENT CHEMISTS OF OUR TIME After a brief interval spent with Boltzmann in Gratz, Arrhenius proceeded to Amsterdam, and became the first foreign student of the physico-chemical laboratory there. Here, as in Riga, Arrhenius's irresistible per- sonality won all hearts. Before many days he was " Dear Svante " to the head of the place, and on terms of intimacy with Mrs. van't Hoff, Eykman, Reicher and Van Deventer the three last being, at that time, the most active workers at the laboratory. If Ostwald did much for his Swedish protege it is but fair to say that van't Hoff did little less. The Stockholm authorities were never for a moment left in doubt as to the opinions these illustrious men had formed of Arrhenius. They were directly responsible for Arrhenius's ultimate appointment in Stockholm, despite the most strenuous objections from the local body. Van't Hoff and Arrhenius were much together in later years. These two, together with their champion, Ost- wald, formed a friendship which is rare even in scientific circles. The two great creators, supported by their great interpreter, made up a trio which led the way in the onward march towards a more rational chemistry. In 1910, some months before van't Hoff's death, Arrhenius paid him a visit in his Berlin home. Writing to Prof. Ernst Cohen, Arrhenius has this to say of what was to prove the last occasion on which he was to see his friend: " At first van't Hoff looked quite a pathetic figure. His voice, always so musical, was now quite hoarse. He was forced to lie on the sofa for pretty nearly the whole day. One morning Schmidt, of the ministry of education, paid him a visit. Van't Hoff was somewhat uncomfortable because this man found him lying down. Later van't Hoff said to me, ' These fellows think that one must be quite a lazy man to be 120 SVANTE ARRHENIUS lying down. But as a matter of fact I read constantly, and make as good progress as if I were sitting up.' I comforted him with the remark that I had done more reading in bed than out of it. I noticed, however, that when he read he soon got tired and put his book aside. There is no question but that he must take the utmost care of himself not to allow matters to take a turn for the worse. "He accompanied me to the Stettin station. We drank three glasses of beer. This was followed by a return to his good old self. The eyes began to twinkle, and the little stories to flow. " He was sorry that we could not remain together longer. 'We are getting old quickly particularly I,' said he, sorrowfully." From Amsterdam Arrhenius proceeded to Leipzig, to the university of which Ostwald had recently been ap- pointed, and here he gave the finishing touches to his now classical paper on electrolytic dissociation a more fin- ished product than his doctor's dissertation. An extract was first sent to Sir Oliver Lodge, and the paper appeared i in its entirety, together with van't Hoff's equally cele- brated one on the analogy between the gaseous and the dissolved state, in volume I of the newly-created Zeit- schrift fur physikalische Chemie. Rarely, if ever, in , the history of chemistry have two such epoch-making papers been published side by side in the same number of a scientific journal. Their publication in 1887 did not lead to immediate recognition, but it did lead to fierce opposition on the ? part of many and thereby gave its authors much notor- ' iety, so that to every chemist and physicist the name of Arrhenius became familiar if only as one associated with wild ideas of a post-impressionistic school. The 1890 British Association meeting at Leeds gave rise to 121 EMINENT CHEMISTS OF OUR TIME verbal cannon which in intensity has been equalled only by a former meeting of this organisation in which Huxley and a bishop played a leading role (see Ramsay). In Berlin the wise privat-docenten spoke learnedly of immature thoughts based on a quicksand foundation. One or two did hint that an idea or two was not wanting, but that only a Helmholtz could have developed these. Even in far-off America Kahlenberg, of Wisconsin, the leading anti-ionist, concluded from his studies as late as ipoo 1 that the dissociation theory was incorrect and doomed to early extinction. But just as in England the agent for the firm of " Ions " had a pretty skilful repre- sentative in the person of Ramsay, so here H. C. Jones, and later T. W. Richards, A. A. Noyes, W. D. Bancroft, J. L. R. Morgan, and others who had imbibed their knowl- edge from the Leipzig school, proved able defenders. In the meantime the " wild army of lonians," as Horstmann had dubbed the celebrated trio, were making no end of noise throughout Europe. Leipzig became the headquarters of the concern, and Ostwald the director. Ostwald's great Lehrbuch der Allgemeinen Chemie, his Zeitschrift and his splendidly equipped physico-chemical laboratory which the university authorities had specially built for him, attrcated enthusiastic students from all over the world who, with their Ph.D.'s in their pocket, with their minds filled with their " ionic " disserta- tions and Ostwald's " ionic " lectures, and, what is far more to the point, with an understanding, after several years of earnest study, of the true merits of the case, spread the new gospel far and wide. 1 It should be added, in justice to Kahlenberg, that some of his criticisms cannot be lightly passed over. That there are imper- fections in the theory Arrhenius himself has been the first to admit, but it is hard to see how, when it has helped to explain so much in our science, it does not contain the germ of some great truth. 122 SVANTE ARRHENIUS In France alone, strangely enough, the new fashion was very slow of adoption. This is all the more strange since two of Arrhenius' s illustrious forerunners, Gay- Lussac and Raoult, hailed from there. Perhaps the second startling development in modern chemistry, radium, which had its origin towards the close of the last century not far from the historic buildings of the Sorbonne, absorbed the French too much. In 1891, only four years after the publication of his paper, Arrhenius was offered a professorship at Giessen, the university made famous by Liebig who, in the minds of a public overfed on " cures " of all kinds, is asso- ciated with " Liebig's Beef Extract." But the Swede politely declined and accepted in its stead a modest lectureship at the Stockholm High School. 1 Four years later he was appointed professor, though not without a struggle ; which clearly showed how strongly opposed the men there were to his views. Arrhenius upon closer acquaintance quickly converted enemies into friends, so that we find that five years after his appointment as lecturer he is nominated Rector, 2 and renominated three times in succession. The third time Arrhenius simply had to refuse, since executive duties were eating too much into his research time. The Germans had tried once to get hold of van't Hoff, and tried again when the first attempt was unsuc- ' cessful, the second time with better results. Their strategy was now repeated. Having failed to get Arrhen- ius for Giessen they, in 1905, offered him a post similar to the one which van't Hoff had accepted several years before as " Academiker " in Berlin; which meant a 1 It should be made clear at this point that the continental idea of a high school is more the equivalent of a university. 2 A position not strictly comparable to any we have in this country. Its nearest approach is that of president of a university. 123 EMINENT CHEMISTS OF OUR TIME full professorship, a private laboratory, a compulsory lecture of once a week and perfect freedom the rest of the time, and an income quite sufficient for modest wants. This he also refused. His countrymen, now quite con- vinced that the world outside of Sweden was ready to acclaim him as one of Sweden's greatest sons, invited him to become Director of the Nobel Institute for Physical Chemistry in Stockholm, a post he still holds. Recently (1919) he was elected vice-president of the Nobel Board of Trustees. Arrhenius's training, as we have seen, had as much and more of physics and mathematics, as chemistry. His great teacher, Edlung, whose electrical problems led him to cosmogenic ones also, probably fired Arrhenius with a desire to invade the domain of astronomy. At the Stockholm High School he gave a course of lectures on cosmic physics, embracing the heavens, earth and atmosphere, which were published in 1901 in a volume of over one thousand pages. This led him to problems which were insoluble if the views then held were applied. The key to much of his difficulty he found in introducing the conception of " radiation pressure " a pressure exerted by rays of light, of heat or of any other kind of radiation when falling upon a surface. With this con- ception in mind, Kelvin's and Helmholtz's theory of panspermia that life-giving seeds drift about in space gains in probability; for, by the introduction of " radi- ation pressure," the difficulty of explaining how germs transported from one planet to another in a time through which their life can be preserved, is largely removed. Solar systems, according to Arrhenius, are evolved from nebulae by collision of suns. Around newly- formed suns there circulate smaller celestial bodies which cool more rapidly than the central sun. " When these satellites have provided themselves with a central crust, 124 SVANTE ARRHENIUS which will partly be covered by water, they may, under favorable conditions, harbor organic life, as the earth and probably also Venus and Mars do." Arrhenius agrees with Helmholtz in denying the trans- formation of inorganic*matter to organic matter endowed with "life." Helmholtz in 1871 said: "It seems to me a perfectly just procedure, if we, after the failure of all our attempts to produce organisms from lifeless matter, put the question, whether life has had a begin- ning at all, or whether seeds have not been carried from one planet to another and have developed everywhere where they have fallen on fertile soil." This theory of panspermia, as further developed by Arrhenius, postulates that the seeds of life, floating in space, occasionally encounter planets, and, provided the condition on these planets is favorable, these seeds, so deposited, may blossom further. If one remembers that the spores of many bacteria are about one millionth of an inch in diameter, it is conceivable that the radiation pressure of a sun would be sufficient to start them off into space. A body moving at the average speed of a train, say thirty-seven miles an hour, would take one hundred and fifty years to go from the earth to Mars, and seventy thousand million years from the solar system to the nearest fixed star, Alpha Centauri. This seems a trifle long for a germ to remain alive! However, the con- ception of radiation pressure as a force reduces the time to twenty days and nine thousand years respectively. Twenty days seems reasonable, but nine thousand i years! Here again other factors must be taken into 'consideration the intense cold, light, dryness, etc., in interstellar space. Both biology and chemistry give Arrhenius' s fertile mind a helping hand. 10 125 EMINENT CHEMISTS OF OUR TIME To begin with, spores of bacteria have been kept for more than six months at two hundred degrees (centi- grade) below zero without appreciable injury, Further, germs of splenic fever, for example, have been shown by Roux, of the famous Pasteur Institute in France, to remain intact by means of light in a vacuum a condition somewhat comparable to that existing in interstellar space. Over sulphuric acid, one of the most powerful substances for absorbing moisture, spores have been kept for twenty weeks without losing their vitality. And now for the climax, with the physico-chemist to the forefront! It is well known that all chemical reactions are con- siderably reduced at low temperatures. A fall of ten degrees (centigrade) reduces the speed of a reaction in the ratio of five to two. " The loss of vitality in inter- stellar space at two hundred and twenty degrees below zero would be more than one hundred million times less rapid than the loss at ten degrees which means that a journey of three million years through space would be no more injurious than a single day of exposure to ter- restrial spring temperature." So what's a mere nine thousand years! In Arrhenius's books, Worlds in the Making, and The Destiny of the Stars, these fascinating problems which fire the imagination are treated at length. It needs to be emphasised here that the meteoric theories of Kelvin, Helmholtz and Arrhenius, while giving us an idea as to the mode of transportation of germs, are irrelevant in so far as origin goes, for in their attempt to explain the first sign of life on this planet they presuppose the existence of a germ elsewhere. Merely to say that life has had no beginning is begging the question. If we must have a hypothesis and this for thinking men is too irresistible we might as well be as 126 SVANTE ARRHENIUS bold as Schafer, the Edinburgh physiologist, who holds that life originated as a result of the gradual evolution of inanimate material. In process of time the simple substance became more and more complex and ulti- mately emerged as the living germ the nitrogenous colloid. But Schafer goes a step further. Why are we to suppose that this happened but once, as all theories with regard to origin have thus far assumed? Why are we to suppose that at one time in the dim past a series of fortunate accidents made life possible? Is it not more logical to assume that these evolutionary processes are going on to-day and will continue to do so? Though even Huxley was of the opinion that at one time there was " an evolution of living protoplasm from not living matter," the idea that we should not relegate the process to some remote period in the past is a com- paratively new one, and has not by any means received the approval of many otherwise loyal chemico-physiolo- gists. These argue, with no small show of reason, that continuous life production would imply similar terrestrial conditions throughout the ages; and this we know not to be the case. The ultra-scientific view, of which Schafer is a shining example, 1 is based primarily upon analogy a very valuable method provided its limitations are not abused, and provided, also, sufficient experimental data are at i hand. The movement of oil drops and the interchange 1 of substance hi osmosis are certainly quicksand founda- tions upon which to build inter-relationship theories of the animate and the inanimate. This superficial con- nection between these physical changes and life processes fails to stand the test of adaptation and coordination to ' name but two characteristic features of the vital sub- 1 See also Prof. Jacque Loeb's Mechanistic Conception of Life. 127 i EMINENT CHEMISTS OF OUR TIME stance. Indeed, our knowledge is so remarkably ex- tensive that we cannot as yet state the simplest vital manifestation in terms of science. If, then, Arrhenius and all others, have failed to solve the riddle as to the origin of life, he has practically solved the mystery of the transfer of life from one planet to another which in itself is a great triumph. 1 If Arrhenius has thought on the subject of life in interstellar space, he has also given attention to the possible better understanding of the living organism by the application of his refined physico-chemical methods to it. In his two books, Quantitative Laws in Biological Chemistry and Immuno- Chemistry, his views are elaborated in a highly suggestive way. In the preface to the first of these he says: "The development of chemical science in the last thirty years shows a steadily increasing tendency to elucidate the nature and reactions of substances produced by living organisms." The problem has been attacked in two ways (a) by the organic chemist, such as Fischer or Kossel, who has elucidated the structure of the molecule, and (b) the physico-chemist, who investigates the nature of chemical processes. Biochemists, says Arrhenius, have thus far shown themselves to be averse to the second method. 2 " Biological chemistry cannot develop into a real science without the aid of the exact methods offered by physical chemistry [quite true]. The aversion shown by 1 It should be added tliat the several romantic touches in Arrhe- nius's cosmic studies have made many scientists hesitate to accept his views without reserve. On the whole, it does seem as if Arrhenius's reputation will rest more on his theory of electrolytic dissociation than on his astronomical work. 2 This, by the way, is not true any more. In America, particu- larly, the physico-chemist as physiologist is not rare; witness Jacques Loeb, L. J. Henderson, D. D. van Slyke, K. G. Falk, etc. 128 SVANTE ARRHENIUS bio-chemists [in the past] who have in most cases a medical education [this is certainly not true either of America or England] to exact methods is easily under- stood. . . . The physical chemists have found that the biochemical theories, which are still accepted in medical circles, are founded on an absolutely unreliable basis, and must be replaced by other notions agreeing with the fundamental laws of general chemistry." Arrhenius's work in this field has been largely hi immuno-chemistry that which deals with the protective agents developed by a body when a toxin, or poison, is injected into the system. The most celebrated attempt to explain the mechanism of this reaction which since yon Berhing's immortal studies have largely absorbed tne labors of many bacteriologists is that known as the Ehrlich " side-chain " theory, which, in its sim- plest terms, tells us that each toxic substance has two groups attached to it a " toxophore " group, with which it exerts its poisonous effects, and a " hapto- phore " group, by means of which it attaches itself to the " receptor " group which is found in every cell, the " heptaphore " and the " receptor " just fitting one another. This combination of cells in the body and the toxins leads to an extra production of " receptor " groups, some of which are thrown off and appear in the blood stream. It is these which constitute the anti- bodies the protective bodies of the organism. Ehrlich was of the opinion that the toxin and anti- toxin neutralise one another in much the same way that a strong base neutralises a strong acid. Arrhenius, however, combats this view, claiming that the union is of a much looser type, belonging to a class known as " reversible reactions." He compares it rather to the union of a weak acid and a weak base, and has applied a well-known mathematical equation in chemical 129 EMINENT CHEMISTS OF OUR TIME dynamics which goes under the name of Guldberg and Waage's Law of Mass Action. It should, however, be added that experimenters are not wanting and they are physico-chemico-bacteri- ologists and not necessarily medical men who regard the toxin-antitoxin combination in the light of an " ad- sorption " phenomena, in some such way, say, that animal charcoal removes colored impurities from vinegar or a raw sugar solution. By 1909, the 25th anniversary of the publication of the theory of electrolytic dissociation, all serious opposition to the more important points in the theory had dis- appeared, and when Ostwald decided to honor the founder by dedicating a whole volume of the Zeitschrift to him, many of the foremost leaders of chemical thought contributed articles for the occasion. One may mention Abegg, Bancroft (Cornell), Le Blanc (Leipzig), Bodenstein, LeChatelier (Paris), Ciamician (Bologna), Dawson, van Deventer (Amsterdam), H. Euler, H. C. Jones (Johns Hopkins), W. Osfwald, G. Tammann, A. E. Taylor (Pennsylvania), R. Wegscheider (Vienna) and H. J. Hamburger. The reaction of the theory of electrolytic dissociation on the chemists who witnessed its birth and watched its growth was well expressed by Sir William Tilden hi 1914, when Arrhenius was the recipient of the Faraday Medal of the English Chemical Society: " With regard to the theory of electrolytic dissociation, which has been the subject of the discourse this evening, my experience, perhaps, is very much that of a good many others, and probably the majority in this room. When it first began to be discussed seriously, close upon twenty years ago, I confess I was among those who were strongly hostile. But I felt, as tune went on, that I had to lay before my students ... at any rate an exposition of what other 130 SVANTE ARRHENIUS people believed in regard to this department of the theory of chemistry; and it was my experience that by merely presenting these views, so new and so unacceptable as they were to me at that time, I gradually got to feel that they were inevitable, and that they were absolutely necessary. ..." Even his own countrymen, with the weight of foreign authority entirely against them, could no longer ignore Arrhenius, and to attack him was no longer safe for one's reputation; so they compromised and presented him with the Nobel prize ! We in America are justly proud of the fact that we were among the earliest to recognise this genius from the north of Europe. He has received and has accepted a number of invitations to lecture here and to enjoy our hospitality. In 1904, at the St. Louis Exposition Arrhenius was one of a group of distinguished foreign visitors which also included Ramsay, van't Hoff, Moissan Ostwald and Hugo Pe Vries. As late as 1911 he gave a series of lectures at our principal university centers. Fairly tall and bulky and robust, he suggests more the prosperous business man than the dried-up philosopher. Like his German and his French, his English, aside from an accent, is clear and correct, and his thoughts are expressed with little effort in this foreign tongue of his. His lectures are like his books his sentences give rise to pages of reflection. The Dutch and the Swedes counting, politically, among the smaller European powers, have given the world two of the greatest, if not the two greatest chemists of our time. Happy will be that nation that will be in a posi- tion to replace every Krupp factory with a great uni- versity and every super-dreadnaught with a van't Hoff or an Arrhenius ! EMINENT CHEMISTS OF OUR TIME References Some of the sources of information are private. A de- lightful account of the origin and development of the theory of electrolytic dissociation has been given by Arrhenius himself in a lecture delivered to the Chicago members of the American Chemical Society in 1911, on the occasion of the presentation of the Willard Gibbs Medal to him (i) . Wilhelm Ostwald contributed a char- acteristically striking portrait of the man and his work when the 25th anniversary of the publication of Arrhen- ius's classical paper was celebrated (2). The late Prof. H. C. Jones, a pupil of Ostwald, van't Hoff and Arrhen- ius, has some good touches of all three in his book, The New Era in Chemistry (3). Cohen, in his van't Hoff (4) devotes much space to the rare friendship which existed between the great Dutch and Swedish masters. Arrhenius's classical paper on the theory of electro- lytic dissociation (5) has been translated into English by Jones (6). Arrhenius himself is responsible for a volume on the theory of solutions (7). The influence Arrhenius's theory has had in laying the foundations for our modern chemistry is well exemplified in the volumes by Smith (8) and Stieglitz (9). Cosmic problems are discussed in 10 and n, and bio- and immune-chemistry, in 12 and 13. 1. Svante Arrhenius: Electrolytic Dissociation. Journal of the American Chemical Society, 34, 353 (1912)* 2. Wilhelm Ostwald: Svante August Arrhenius. Zeitschrift fur physikalische Chemie (Leipzig), 65, V (1909). 3. H. C. Jones: New Era in Chemistry (D. Van Nostrand Co. 4. Ernst Cohen: Jacobus Henricus van't Hoff (Akademische Verlagsgesellschaft, Leipzig. 1912). 5. Svante Arrhenius: Ueber die Dissociation der in Wasser gelosten Stoflfe. Zeitschrift fur physikalische Chemie, 1, 631 (1887). 132 SVANTE ARRHENIUS 6. H. C. Jones: The Modern Theory of Solution (Harper and Brothers. 1899). 7. Svante Arrhenius: Theories of Solution (Yale University Press. 1912). 8. Alexander Smith: Introduction to Inorganic Chemistry (The Century Co. 1917). g. Julius Stieglitz: The Elements of Qualitative Analysis (The Century Co. 1913). 10. Svante Arrhenius: Worlds in the Making (Harper and Brothers. 1908). 11. Svante Arrhenius: The Destinies of the Stars (G. P. Putnam's Sons. 1918). 12. Svante Arrhenius: Quantitative Laws in Biological Chemistry (G. Bell and Sons, London. 1915). 13. Svante Arrhenius: Immuno-Chemistry (Macmillan Co. 1907). 133 HETTCY MOISSAN year 1907 was a particularly sad one for the world of science. Within a few months of Moissan's death science lost such intellectual giants as Perkin, Men- deleeff, Berthelot, the French chemist, Boltzmann, the Austrian mathematical physicist, Sir Michael Foster, the English physiologist, and Prof. Marshall Ward, the English botanist. In the history of chemistry France occupies a proud position. One of her sons, Lavoisier of immortal mem- ory, is the founder of the science of modern chemistry. Another, Berthollet, had much to do with developing a chemical nomenclature. Berthollet's assistant and suc- cessor, Gay-Lussac, has given us the celebrated law of gases known by his name. Dumas was a master of atomic weight determinations. Berthelot was a minister of state, as well as a great authority on thermochemistry. In St-Clajre Deville we have one of the founders of physical chemistry. Pierre Curie had much to do with the discovery of radium. Moissan rightfully takes his place among such illus- trious scholars. He began his labors at a tune when chemists had all but deserted the field of inorganic chemistry for the chemistry of the carbon compounds. The cry had been raised that inorganic chemistry had exhausted itself. Moissan's work soon convinced people that the cry was a false one. Inorganic chemistry had, and still has, rich fields for investigators. What was needed was a man of genius ; and such a man was found in the person of Moissan. 135 EMINENT CHEMISTS OF OUR TIME Starting with his isolation of fluorine, the most active of the elements, and one closely allied to chlof ine of gas cloud fame, Moissan, from a study of the compounds of fluorine, was led to his celebrated experiment on the artificial production of the diamond, and this latter hi turn led to the electric furnace. With the electric fur- nace, scores of hitherto scarcely known elements and compounds were prepared; among them, calcium car- bide, the source of acetylene. Moissan's work, unlike many of the other great work- ers in the field, had an immediate practical bearing which the layman could appreciate. Thus the electric furnace readily found a place in metallurgy, and the need for acetylene gave rise to an immense calcium carbide industry. Yet Moissan remained a compara- tively poor man to the day of his death. His discoveries, instead of being patented, were published hi the French chemical journals, to be used by readers hi any way they saw fit. He was a professor, and as such he was em- ployed by, and worked for the people. The discovery itself, and not what the discovery could bring to him, counted with Moissan. In this connection it is important to emphasise some- thing else. One must not measure the greatness of a man of science by the standard whether his work can find immediate application hi everyday life. Were such a test to be applied, very few great scientists would remain. The application of the laws and discoveries of science come with tune, sometimes sooner, sometimes later, but come they do. It is therefore particularly difficult to point out the practical significance of the more recent contributions to chemistry. Yet even here re- sults often show themselves sooner than expected. Thus, to take two cases at random, van't Hoff's profound studies of chemical dynamics have had no small share in 136 HENRY MOISSAN contributing to the solution of the synthesis of ammonia from its elements; and Arrhenius's theory of electro- lytic dissociation has opened up new vistas in biological research. Ferdinand Frederick Henri Moissan, to give nun his full name, was born in Paris on September 28, 1852. We can afford to be even a little more specific; we can add that the name of the street was Rue Montholon, and the number of the house, 5. His father, a native of Toulouse, held a position with the Compagnie des Chemins de Per de VEst. His mother (nee Mitelle) belonged to an Orleans family. In 1864 the family moved to the small city of Meaux, and here Henri was sent to the municipal school. Among the teachers at the school was one, James, who taught mathematics and the natural sciences. The good directors were evidently of the opinion that while it may take several men to master one subject such as Greek, it probably does not take more than one to master several subjects such as chemistry, physics, astronomy, biology, etc. with mathematics thrown in to give more symmetry to the list. However, James was a very good teacher, and he early recognised hi Moissan a boy out of the ordinary. James offered to give Moissan private lessons in addition to the instruction at school; this the boy gratefully accepted. In addition to James's exposition of the sciences, Moissan had another helper in his father. His father's particular science was chemistry, and Moissan began to receive elementary instructions in chemistry when he was fourteen years old. " J'avais commence a mani- puler de Page de 14 a 15 ans," writes Moissan; " et mes premieres legons de chimie, donnees par mon pere, sont encore gravees dans ma memorie." 137 EMINENT CHEMISTS OF OUR TIME Probably because of financial difficulties, Moissan left the school in 1870 without passing his university entrance examination, to the keen disappointment of his teacher, James. Moissan set out for Paris. His preference for chem- istry led him to seetf a position as an apprentice in a drug store, or apothecary's shop. Such a position he found at a pharmacist's located at the corner of Rue Pernelle and Rue Saint-Denis; and here soon afterwards he achieved his first victory over nature by saving a man's life who had attempted suicide with a dose of arsenic. Duties at the store gave no time for study, and with- out passing several important examinations there was no hope of ever becoming a pharmacist. At this point it is perhaps necessary to inform some readers that the pharmacist hi France or Germany is one who has gone through a much more thorough course of training in preparation for the practise of his profession than the druggist (self-styled " chemist ") in England or America. As a matter of fact, the pharmaceutical student is very much of a university student, and his training is correspondingly thorough. Moissan had a school chum, Jules Plicque, who attended Deherain's lectures at the Musee d'Histoire Naturelle, and Plicque told Moissan wonderful things of Deherain and the Museum. Moissan paid more and more attention to these accounts. He was ambitious; he wanted to become a real scientist, and for this, further schooling was necessary. Moissan quit his " job " in 1872 and went to Fremy at the Musee. He supported himself as best he could by giving private lessons, and lived in the hope that some day he would be an industrial chemist making as much as 3,600 francs per year! Three thousand six hundred francs was the very maximum to which this lad of twenty 138 HENRY MOISSAN aspired. How poor financially he was then can well be imagined. Two years later Moissan exchanged Fremy for De- herain, the teacher of his friend Plicque. Deherain soon took notice of Moissan. The young man's leaning towards industrial chemistry was not discouraged by his teacher, but hopes were also held out that good work, coupled with the fulfilment of several university require- ments, might lead to an academic position. An academic position was what Moissan wanted far more than any industrial one, but until then the poor lad had thought any such goal entirely beyond his reach. He now prepared actively for his university degrees. For the time being much of the chemistry work had to give place to the classics and physics subjects which he had neglected since his school days. In 1874, after several attempts, he obtained his bachelor's degree, 1 and in 1877, his Licencie es Sciences. Even during these days of hardship life had its bright spots. At the Museum he formed a close friendship with Vesque, the botanist, and Etard, the chemist; and during his army service at Lille in 1876 he got to know Beclere, Siredey and Walter, all three medical men. These six formed a very close circle. Not only was science fostered among them, but literature and the arts were also cultivated. This intellectual group proved of immense value to Moissan, whose irregular education needed polish to round it out. He acquired a taste for painting, sculpture, historical studies and belles-lettres, and incidentally 1 To get a bachelor's degree at the University of Paris, or at an English university particularly London, exhaustive final examina- tions, theoretical and practical, have to be passed. It is not unusual even for good students to fail in their first attempt. 139 EMINENT CHEMISTS OF OUR TIME mastered his own language in a way which was of in- valuable help to him later as lecturer and writer. This love of literature led the young man to attempt the writing of a play so often an emotional outlet for the youths below and above twenty. The play must have had merits, for it came near being produced at the Odeon. Perhaps it was as well that the play was not produced, for it might have made him neither a good dramatist nor a good chemist. " Je crois que j'ai mieux fait de faire de la chimie," was Moissan's own comment. The days of youth and health and hope are always delicious memories. Moissan loved to recall the times when he and his friends, poor in pocket but rich in mind, lived and laughed and were happy. Vesque, who, with his violin, gave meaning to Beethoven, did much to spiritualise the souls of the little company. Deherain being interested in plant physiological chem- istry, Moissan's first research naturally fell in this field. It dealt with the interchange of oxygen and carbon di- oxide in the leaves of plants, and was used as a part thesis for the apothecary's license. But even during the progress of this research Moissan had decided not to specialise in organic chemistry. Deherain's advice against such a step did not change Moissan's decision; the young man wished to turn his attention to inorganic chemistry. But did Moissan know that inorganic chemistry offered but a barren field? No matter, said Moissan, it can still be culti- vated. We are not sure just what led Moissan to such a happy choice. Perhaps Dumas' complaint in 1876 had something to do with it. " Notre pays," said Dumas, " tient largement sa place en chimie organique, il neglige trop la chimie de corps inorganiques."_ And 140 HENRY MOISSAN what was true of France was true of the rest of Europe. Yet even France had a man, St. -Claire Deville, whose fame did not rest upon his organic chemistry researches. Neither, however, did they deal with the purely inorganic, for the vast subject of dissociation belongs to a third branch of the science physical chemistry. Whatever the reason, nothing could have been more fortunate. What the renaissance was to the revival of learning in Europe, Moissan became to the revival of inorganic chemical scholarship in the universities and factories. Of his three hundred papers or so, almost every one deals with experimental inorganic chemistry. Very few touch even upon theory. They were published either in the proceedings of the French Academy, in the Annales de Chimie et de Phisique, or in the Bulletin de la Societe chimique de Paris. In 1879 Moissan obtained his diploma of Pharmacien de premiere Classe, and in the following year he was granted the degree of Docteur es Sciences physiques with the presentation of a thesis on the oxides of chro- mium one of his earliest papers in his newly-chosen field. The first academic appointment came to him when he was twenty-seven years old. It was as Repetiteur [instructor] de Physique at the Agronomic Institute. In the following year he was made Maltre de Con- ferences [lecture assistant] and Chef des Travaux Pratiques [senior demonstrator, or associate] at the Ecole Superiore de Pharmacie. Before he left the town of Mieux several years pre- viously, Moissan became acquainted with one Lugan, a pharmacist, and incidentally with his daughter. Lugan had a perfect passion for chemistry, and hence followed Moissan's career with much interest. Moissan on his ii 141 EMINENT CHEMISTS OF OUR TIME side liked Lugan, Lugan's chemistry and Lugan's daughter. In 1882 Moissan's courtship and prospects had both made sufficient strides for marriage to appear within the bounds of reason. The docteur was not only accepted by Leonie y but Leonie's papa provided comfortably for the pair. With a stroke Moissan became the happiest of men. The marriage proved as perfect as a marriage between two human beings can possibly be, and the income pro- vided by the father-in-law removed the chief source of worry for the future. In 1885 a third member of the family, Louis, joined them. " If I am not in my labor- atory I want to be in my home." What better com- mentary on the home atmosphere is needed than this remark of Moissan's? The work which, beginning in 1884, led Moissan to his first great achievement, the isolation of fluorine, has a history. Fluorine in the form of its compounds had long been known. Without ever having been isolated, the ele- ment was included in the group of elements known as the halogens, or salt producers, because its salts showed striking similarities to salts of the rest of the group. The commonest member of this family is chlorine, and its sodium salt, sodium chloride, is the table salt so indispensable as a food. The other elements belonging to the halogens are bromine and iodine. Chlorine was discovered as far back as 1774 by Scheele, the famous Swedish chemist. In 1811 Courtois discovered iodine in the ashes of sea-weed, and fifteen years later Balard discovered bromine. It was not, however, till 1886 that the fourth, and last member of the family, fluorine, was isolated by Moissan. The activity of this element it is the most active (i.e., 142 HENRY MOISSAN chemically active) element known had prevented its isolation prior to this date. Scheele himself, who was familiar with the acid de- rived from fluorine, hydrofluoric acid, began experiments on the latter substance towards the close of the eighteenth century, but nothing came of them. Davy, the English chemist, made an attempt in 1813 to isolate fluorine by passing an electric current through hydrofluoric acid. The method, with modifications, was successfully used by Moissan later on; but in Davy's case the fluorine was no sooner liberated than it attacked the water and anything else that happened to be present, at the same time being itself transformed into one of its compounds. Gay-Lussac and Thenard were not more fortunate. Knox, a Scotsman, spent three years on this problem, and then had to go to Italy to recruit his health which was shattered by the unavoidable inhalation of the vapors of toxic gases. Louyet, another worker, died of their effects. In 1850 Fremy, one of Moissan's teachers, came near to success by his preparation of anhydrous (that is, water-free) hydrofluoric acid. Moissan attacked the problem in 1884 " in the un- certain hope of at last being able to isolate the element." By the distillation of a mixture of arsenious oxide, oil of vitriol and fluorspar, he obtained a fluoride of arsenic which, when electrolysed, gave him arsenic and a gas which immediately attacked the platinum electrode. Moissan now returned to Davy's and Fremy's experi- ments. Davy's hydrofluoric acid alone would not do because it contained water, and Fremy's anhydrous | variety had the drawback in that it was a non-conductor I of electricity. Moissan's success depended upon the fact that the addition of potassium acid fluoride to the anhydrous hydrofluoric acid converted the latter into a conductor. 143 EMINENT CHEMISTS OF OUR TIME To withstand the action of fluorine, the apparatus was made of an alloy of platinum and iridium, an extremely expensive combination. Later, however, Moissan found that copper could be substituted, for though the fluorine attacks the copper, the resulting copper fluoride acts as a protective coating, and prevents further disintegra- tion of the vessel and loss of the fluorine. On June 28, 1886, Debray, acting on behalf of Moissan (who was not yet a member) announced to the French Academy Moissan's isolation of fluorine. Such an announcement was much too important to be passed over without further notice. The president appointed Berthelot, Debray and Fremy to investigate and report on Moissan's work. Lo and behold! in the presence of these august men Moissan could not get any fluorine ! He tried and tried, but no fluorine I The folio whig day the substitution of new materials for old ones solved the difficulty, and soon after that the Academy's representatives were convinced of the legitimacy of Moissan's claim that he had really succeeded in isolating this most elusive of all the elements. Moissan showed that no element was safe from the attacks of fluorine; it readily combined with most of them to form fluorides. But with Ramsay's " inert " gases of the atmosphere, such as argon or helium, it showed no action whatsoever. Much later, in conjunction with Dewar, the famous English experimenter on the liquefaction of gases, Moissan succeeded in liquefying fluorine at a tempera- ture of 185 degrees (centigrade) below zero; and even at this temperature, though the liquid no longer has any action on glass, it still attacks hydrogen and hydro- carbons. This is remarkable, for we know that just as an increase of temperature accelerates chemical reac- 144 HENRY MOISSAN tion, so a decrease of temperature retards it. At 185 below zero few, if any substances, have much chemical action. But another very remarkable fact must now be cited. The researches of Victor Meyer in Germany, and par- ticularly those of Dixon and Baker in England, have shown that substances tend to combine less and less the drier they are. If in addition to being absolutely dry, the substances are also absolutely pure, it is ques- tionable if any chemical reaction is at all possible. In any case, in this connection it is interesting to note that perfectly dry fluorine has no action on clean, dry glass ! Moissan's researches on fluorine were published in book form in 1891 and republished in 1914 as one of a series belonging to Les Classiques de la Science. Ostwald several years ago in his Klassiker commenced the republication in pamphlet form of some of the more classical researches in the history of chemistry. A French committee consisting of H. Abraham, H. Gautier, H. Le Chatelier and J. Lemoine, arranged for the French public a Classiques comparable to the German Klassi- ker. Beyond one or two sporadic attempts, nothing like these have appeared in English. Why? Are we for- ever to lag behind? Before dismissing the subject of fluorine, it should be added that recently W. L. Argo, an American electro- chemist, has suceeded, by a modification of the Moissan method, in getting fluorine easily and in quantity. Moissan's success in isolating fluorine did not go unrewarded. The Academy awarded him the Prix la Caze prize of 10,000 francs, and soon afterwards (in 1886) he was appointed professor of toxicology at the Ecole de Pharmacie^ in succession to Bouis, the dis- coverer of caprylic alcohol. Now for the first time MS EMINENT CHEMISTS OF OUR TIME Moissan had his own laboratory a small one, but yet his own. The isolation of fluorine was quickly followed up by an exhaustive study of the combinations of fluorine with other substances. Among these were the compounds of fluorine with carbon. Moissan had dim hopes that by utilising the activity of fluorine the carbon could be separated in the crystalline form of diamond. Moissan found that he could get two combinations of carbon and fluorine, but these, when decomposed, left only common carbon. This led him to a systematic study of the varieties of carbon, and the methods of changing one variety into another. Diamond, graphite, lampblack, boneblack and large percentages of coal and coke, are really nothing more than different forms of one element, carbon. The chemist gives the name " allo tropic " to such different forms of one element. Allotropic elements show the same com- position, though the internal structure of the atoms are probably different. Diamond, graphite, lampblack, etc., when completely burned, all give carbon dioxide and nothing else, proving the identity of these allotropic forms. It is easy enough to convert diamond into one of the other forms of carbon by strongly heating it, but until Moissan's time no one had succeeded in the reverse process. Before, however, this could be accomplished, Moissan had to devise some scheme for getting much higher temperatures than were then available. This led to his famous electric furnace. In its simplest form (see diagram on the opposite page) it consisted of two blocks of lime with central cavities for the crucible containing the material to be used, and horizontal cavities for the carbon electrodes. The furnace measured some 6" x 6" x 7", and required 146 Moissan's electric furnace. Moissan's apparatus for preparing fluorine. [Reproduced from Moissan's books.] HENRY MOISSAN a current of four horse-power (about 60 amperes and 50 volts). With it Moissan obtained temperatures in the neighborhood of 4000 Centigrade. Now out in Arizona Dr. Foote, a mineralogist, had shown that the Canyon Diablo meteorite contained microscopic diamonds, and Moissan's careful study of the possible formation of these precious stones led him to the belief that they were formed from ordinary carbon as a result of great pressure. Accordingly, in one of his experiments Moissan heated some pure iron mixed with carbon (obtained from the calcination of cane sugar) in his electric furnace. The iron melted like wax at the enormous temperature of the furnace, and dissolved portions of carbon in much the same way that water dissolves common salt. After a few minutes at 4,000 centigrade, the crucible containing the molten mixture was plunged into cold water. In this way the outer surface of the iron cooled more quickly than the inner portion, and thereby brought a terrific pressure to bear upon the inner contents, still in a liquid state. By this means, part of the carbon was converted into the diamond form. After suitable re- moval of various impurities, the residue, partly trans- parent, partly black, and microscopic in size and amount, was shown to possess the characteristic hardness of diamond, as well as its crystalline structure (octahedral facets). However, the artificial production of the diamond, a scientific fact to-day, is not a commercial success as yet. The small size of the stones, and the cost of their production, make it quite improbable that, for the present, the laboratory of the chemist will attempt to compete with nature's laboratory. As with Madame Curie's discovery of radium several years later, the artificial production of the diamond was 147 EMINENT CHEMISTS OF OUR TIME splendid material for newspaper gossip, and poor Mois- san, the most modest of men, found himself lionised by all Paris. Diamonds, said the newspapers, could be made so easily by Henri Moissan, that they would soon be had for the mere asking. What would the De Beers Company in South Africa do? Many of Moissan's subsequent experiments were made with the help of the electric furnace. The pre- liminary operations were first carried out at the works of the Edison Company in Avenue Trudaine; later the basement of the college was equipped for this purpose. By means of the electric furnace and the high heat thereby afforded, Moissan liquefied and volatilised such metals as copper, silver, platinum, gold, tin, iron, etc. Extensive researches on the combinations of the ele- ments with carbon, boron and silicon to form carbides, borides and silicides respectively, were carried out. Perhaps the most notable of these was the preparation of calcium carbide, which hi the presence of water yields the important illuminating gas, acetylene. Moissan also prepared silicon carbide, or carborundum, but he does not seem to have attached any importance to this dis- covery. The method of preparation was also a poor one. The discovery of carborundum is therefore very right- fully assigned to Acheson, the American industrial chemist, who, working quite independently, and using a much more practical method (sand and coke) for its preparation, arrived at the same result, and immediately took out a patent for the process. The study of carbides also led Moissan to a theory of the origin of petroleum. In brief, Moissan's view was that water, acting on carbides, gave rise to various hydrocarbons which, when mixed, constitute petroleum. With the electric furnace as with fluorine, Moissan embodied the results of his researches in book form 148 HENRY MOISSAN under the title Le Four Electrique. In the preface to this work we find an admirable spirit admirably ex- pressed : " But what I cannot convey in the following pages is the keen pleasure which I have experienced in the pursuit of these discoveries. To plough a new furrow; to have full scope to follow my own inclination; to see on all sides new subjects of study bursting upon me; that awakens a true joy which only those can experience who have themselves tasted the delights of research." The work consists of four chapters. In the first, various types of the electric furnace are discussed. In the second, the results of studies on the three varieties of carbon the diamond, the graphite and amorphous carbon are recorded. Chapter three deals with the preparation of several simple substances by means of the electric furnace, and also describes researches on the preparation of chromium, manganese, molybdenum, tungsten, uranium, vanadium, zirconium, titanium, silicon and aluminium. 1 Chapter four describes the preparation of various carbides, silicides and borides, calcium carbide receiving particular attention. In 1904 Moissan, as chief editor, published the Traite de Chimie Mineraile, a comprehensive work (in five volumes) on inorganic chemistry. His collaborators numbered some of the most distinguished French chemists, such as Gautier, Le Chatelier, Sabatier, etc. It has been pointed out that in 1886 Moissan became professor of toxicology at the School of Pharmacy. It was not until thirteen years later that he succeeded to the chair of " mineral " or inorganic chemistry. Strangely enough, during all these years, though his research work 1 The f easability of preparing aluminium (or, as it is sometimes called, aluminum) on a large scale was first successfully demon- strated by Hall, an American, in 1886. 149 EMINENT CHEMISTS OF OUR TIME was pre-eminently inorganic, his lectures dealt with an entirely different subject. In 1900, on the retirement of Troost, Moissan was unanimously chosen Professor of Inorganic Chemistry in the Faculte des Sciences in the University of Paris; he, however, retained his title of professor at the Ecole de Pharmacie. In 1888, as a result of his isolation of fluorine, Moissan was elected a member of the Academy of Medicine. Three years later Cahours* death left a vacant seat hi the Academie des Sciences. To fill this place the names of Moissan, Grimaux, Ditte, Jungfleisch and Le Bel were submitted. After a discussion of two hours the committee decided to nominate Moissan and Grimaux. The latter was subsequently defeated by eleven votes, and Moissan thereby became the confrere of Berthelot, Friedel, Schiitzenberger and Troost. Election to the Academy is the highest honor a French man of science can attain in his own country. In 1896 the English Royal Society awarded its Davy Medal to Moissan, " in recognition," said the president, Lord Lister, " of his great merits and achievements as an investigator. The electric furnace of M. Moissan has become the most powerful synthetical and analytical engine in the laboratory of the chemist." Moissan, proceeded the president, had obtained substances whose very xeistence had been undreamt of. It was impossible to foresee the bounds to this new field of Research. In this same year the Royal Society awarded its Copley medal to Carl Gegenbauer, the Heidelberg anatomist, the Royal Medal to Archibald Geikie, " the most distinguished British geologist," and the Rumford medal was divided between Phillip Lenard and W. C. JRontgen, whose work paved the way for the discovery of radium several years later. 150 HENRY MOISSAN In 1903 Moissan was selected as Hofmann Medallist of the German chemical society; and in 1906 he was awarded the Nobel Prize for chemistry. The other Nobel winners for 1906 were J. J. Thomson, the dis- tinguished English physicist, Camillo Golgi, of Pavia and Ramon y Cajal, of Madrid both anatomists, Carducci, the Italian poet, and Theodore Roosevelt. " Moissan," says Ramsay, who knew him well, " was a practised speaker and a perfect expositor. His lectures at the Sorbonne were crowded with enthusiastic students, all eager to catch every word, and he kept their attention for one and three quarter hours at a time by a clear, lucid exposition, copiously illustrated by well-devised experiments. " His command of language was admirable ; it was French at its best. The charm of his personality and his evident joy in exposition gave keen pleasure to his auditors. He will live long in the memories of all who were privileged to know him, as a man full of human kindness, of tact, and of true love of the subject which he adorned by his life and work." At five in the afternoon the doors of the big lecture room were opened, and the students made a rush for front seats. For the next fifteen minutes, until the appearance of the professor, the young men passed the time by shouting and singing songs. Punctually at five- fifteen Moissan would walk in, and immediately a pro- longed sh sh resounded through the hall. Woe to the student who made his appearance after five-fifteen! The booing and stamping left the late intruder in no false notion as to the opinions of his fellow-students. Moissan was little of a speculator. His papers are remarkably free of theories; they record merely the work done in the laboratory, and the conclusions to be drawn from such work. But it does not follow that EMINENT CHEMISTS OF OUR TIME Moissan had no definite goal in mind, or that he failed to grasp the significance of facts and theories. On the contrary, few men have followed up clues so systemati- cally, or drawn such sound conclusions from their work. But Moissan was essentially a " practical " man, who loved to handle things in the laboratory, rather than speculate about them in his office. He is the author of no hypothesis, of no theory; certainly of no law; but as an experimenter few have rivalled him. " Je me suis applique*," wrote Moissan, " a cultiver cette chimie minerale que l'o# croyait epuisee, et je pense que mes travaux, ainsi que le belle reserches des savants anglais, ont pu demontrer que cette science reserve encore bien des decouvertes a ceux qui voudront 1'aimer et Petudier avec tenacite"." Moissan's fame attracted foreign students, particu- larly after his invention of the electric furnace, which opened up such vast possibilities in research at uni- versities and industrial plants. In 1899, in addition to a number of French workers, Moissan had in his research laboratory two Germans, one Austrian, one Englishman, one American and two Norwegians. Despite research which was often not quantitative in character, and usually planned on an industrial scale, Moissan insisted upon scrupulous cleanliness in the laboratory. A few drops of water on the laboratory floor would make Moissan exclaim, " Qui a fait cela? " He certainly gave the lie to Riess's remark that chem- istry is the dirtiest part of physics! With his wife and his son, Louis his only child Moissan spent his vacations travelling through pictur- esque parts of Europe. But as a representative of the French Academy, his trips were often extended to include centers of learning. Thus in 1904 we find him at the St. Louis Exposition in company with such distinguished 152 HENRY MOISSAN foreign delegates as Hugo de Vries, Ramsay, Arrhenius, Ostwald, etc. Moissan died in 1907 from an acute attack of appendi- citis. There can be little question that the inhalation of toxic gases such as fluorine and carbon monoxide the latter a by-product of the electric furnace shortened his life by a number of years. " My life," said Moissan towards the close of his career, " has been of the simplest happy in my labor- atory and in my home." G. B. Shaw, in his preface to Overruled, tells us that "industry is the most effective check on gallantry." That certainly helps to explain why research workers in science are, almost without an exception, very happily married. On August 10, 1915, Louis, Moissan's only son, died on the field of battle. The young man who, prior to the outbreak of the war, was an assistant at the college made famous by his father, the Ecole de Pharmacie, left to this institution the capital sum of 200,000 francs for the foundation of two prizes one for chemistry (prix Moissan), and one for pharmacy (prix Lugan),'m memory, respectively, of his father and mother (nee Lugan). References Paul Lebeau, one of Moissan's assistants, wrote a very comprehensive review of the life and labors of his master (i). Alfred Stock, another of Moissan's stu- dents, is the author of an equally good obituary notice (2). Sir William Ramsay's Moissan Memorial Lecture (3) is a rather poor specimen of the gifted Englishman's productions. Moissan's researches on fluorine have been published in book form (4). His work on the electric furnace (5) 153 EMINENT CHEMISTS OF OUR TIME devotes a chapter to his experiments on the diamond. Sir William Crooke's article on artificial gems in the Encycl. Britannica (6) is well worth consulting. z. Paul Lebeau: Henri Moissan. Bulletin de la societe chimique de France (Paris), 3, i (1908). 2. Alfred Stock: Henri Moissan. Berichte der deutchen chem- ischen Gesellschaft (Berlin), 40, 5099 (1907). 3. Sir William Ramsay: Moissan Memorial Lecture. Journal of the Chemical Society , 101, 477 (1912). 4. Henri Moissan: Le Fluor (Libraire Armand Colin, Paris. 1914). 5. Henri Moissan: Le Four Electrique (G. Steinheil, Paris. 1897). 6. Encycl. Britannica, nth ed. MARIE SKLODOWSKA CURIE ^NCE," says Anatole France, " has two geniuses Rodin and Madame Curie." The foremost scientist of France, and the greatest woman scientist in the history of mankind, she counts politically less than many a man fit for the lunatic asylum. And as if to encourage that conception of woman to which so many men cling tenaciously, the French Academy, numbering among its members the elite of French intellect, decide that woman, be she ever so much a genius, cannot be ad- mitted into their sanctum. If further proof were needed that intellect often runs counter to freedom, and that scientists who work so strenuously for an en- largement of their scientific horizon often belong to the most reactionary group in politics, the case of Madame Curie affords an excellent example. Within the space of ten short years this woman has created a new science, radioactivity, and this has opened up more fertile chemical soil than any other discovery in the history of science. It has given us the first clear insight into the chemist's promised land, the nature and possible structure of the atom, and holds possibilities which could hardly have been hoped for from the accumulated labors of scientists during the last hundred years. In speed of progress radioactivity is to the science which has gone before what the aero- plane is to the tortoise. This momentous discovery belongs to Madame Curie. To be sure, the way was paved for her by many; to be sure, her husband was a good helpmate; but in spite of 12 i55 EMINENT CHEMISTS OF OUR TIME analogous work in various parts of the world by the world's most gifted scientists, this woman triumphed where all others failed, and to her belongs the reward. Since her great discovery towards the close of the ? eighteenth century, her researches on radioactivity have but added to her glorious reputation, so that to-day she stands crowned as the greatest woman and among the very greatest scientists of all times. The inherent qualities which go to the making of genius certainly never have been the exclusive posses- sion of half mankind, but whereas the male geniuses have, at times, been allowed to blossom, the females belonging to this species, have until recently, been sup- pressed with a Cossack's ferocity and a Cossack's justice. The past four years of critical history from which mankind has just emerged will, perhaps, help to remove the mental fog which has incapacitated many a man from using his brains to the advantage of himself and of the world. Madame Marie Sklodowska Curie was born in Var- sovie or Warsaw, Poland, on November 7, 1867. Her father, Dr. Sklodowski (" squadoffski " to give it the Polish pronunciation) was a professor in the gymnasium of the town, and locally known as a good teacher and sound scholar. The death of her mother left little Marie much adrift, though a brother and sister were there to share the misery; and were it not that from her earliest years a magnetic force attracted her to the father's laboratory, Marie would have been left much to herself, for her father's life was his work. As it was, the girl's love for science made the father her wor- shipper, and until she was old enough to attend school, Dr. Sklodowski was her sole teacher. The part of Poland in which Marie lived had become part of Russia, the two remaining portions having gone 156 MARIE SKLODOWSKA CURIE to Russia's appetizing neighbors, Germany and Austria. It was bad enough for a Russian to have lived in Russia under the Czar's regime, but for the Pole conditions were about as intolerable as for the Jew, and the sensi- tive girl, fired by her father's patriotism, came to hate the Russian persecutors with the zeal of a religious fanatic. Revolution was in the air; everybody who was anybody the Pole and the Finn because of the Russian, and the Russian because of the autocracy was a revo- lutionist, ready at any time to taste misery in Siberia for the holy cause. Marie joined the ranks. Meetings were held, plans drawn, and prayers offered for the success of the independent movement. Unfortunately, the police got wind of the affair. A number of Dr. SklodowskL's students were among the ringleaders, and Marie herself was more than a mere onlooker. This led to her decision to leave Poland. Her first intention was to proceed to Cracow, the seat of an historic university. Cracow, the ancient capital of Poland, was now part of the Poland belonging to Austria, whose rule, however, was quite benevolent as compared to the rule of her Russian neighbor. Here, unlike Warsaw, the Polish language was allowed, and Polish history and literature cultivated. But Marie had visions. She wanted a bigger uni- versity still, and a bigger town, yet a town that would remind her of her beloved Warsaw. Paris was such a place. Even as far back as 1810 Napoleon had recog- nised the relationship, for he said, " Varsovie petite Paris." To Paris then went Mile. Sklodofska, just as many of her countrymen had done before. Times change. In those days Mile. Sklodofska would hardly have dared to hope that within fifty years her beloved fatherland would come into its own again, and, as a buffer power between Russia and Germany, help to 157 EMINENT CHEMISTS OF OUR TIME preserve the peace of Europe. Chopin and Sienkiewicz no longer live to witness this glorious day, but Conrad from London and Mme. Curie from Paris can watch Poland's revival and its effort to rehabilitate itself among the nations. Miss Sklodof ska did not arrive in Paris as a conquering hero. Far from it. Her pockets were empty and her acquaintances few. She established herself in the " east side " section of the town, in a small back room, four flights high, to which she carried her own coal. Her diet consisted of bread and milk for so long that, as she herself has said, she had to acquire anew the taste for wine and meat. Ten cents were her daily expenses, and this she made largely by private tutoring, and later, by preparing the furnace and washing bottles at the Sorbonne. To other geniuses, Ramsay and van't Hoff, for ex- ample, such struggles were unknown. They were given what they wanted and were encouraged to do their best. The struggle for existence was not a problem to them. To Mme. Curie, once outside her father's home, this struggle became paramount. Yet to conclude from this, as many wiseacres are fond of telling us, that the struggle made the woman, is as near the truth as to conclude that its absence made Ramsay or van't Hoff. Material comforts make the path easier, and their absence make it infinitely more difficult. That Madame Curie did not succumb, as many another budding genius has under like circumstances, is an accident as a result of which the world has been made much the wiser. In those days the head of the physical science depart- ment at the Sorbonne was Gabriel Lippmann, whose pioneer work in color photography is known wherever physics flourishes. He was attracted by the superior knowledge which Miss Sklodof ska showed in the execu- 158 MARIE SKLODOWSKA CURIE tion of her work, which developed from washing bottles to setting up apparatus. Henri Poincare, the great mathematical philosopher, and a brother of the late president of France, was another one upon whom this young girl had made an impression. They acquainted themselves with her history. Lippmann got into touch with her father in Warsaw. The result was that Marie was put into the hands of Pierre Curie, one of Lippmann's most promising pupils. Given a scholar, an impressionable young man, one who had met few people and who had become absorbed in his work, and a bright girl, with a personality, and a keen interest in the same type of work; given further that the man and the woman see one another daily for the greater part of the day, and the possible outcome might have been forseen. "What a grand thing it would be to unite our lives and work together for the good of science and humanity," runs one letter from Pierre. "For the good of science and humanity" smacks of too much altruism hi a marriage proposal, but innocent Pierre Curie meant well, and Miss Sklodof- ska understood and sympathised and accepted. So in 1895 the two were married, both poor in life's necessities, but rich in sympathy toward, and under- standing of one another. Curie continued his re- searches on the construction and use of electrometers and condensers, and Mme. Curie assisted in this, and also prepared herself for her degree. Within three years she gained her licenciee &s Sciences mathematique et es Sciences physiques, and unlike Pasteur or Ehrlich, who made a poor impression on the examiners, Mme. Curie passed her examination in brilliant style. Here again no moral should be drawn; not all poor students become Pasteurs, nor do all senior wranglers become Curies. 159 EMINENT CHEMISTS OF OUR TIME We now come to Madame Curie's immortal piece of work. To get the proper perspective a short introduction is necessary. From about 1860 on, many interesting but discon- nected observations had been made on the passage of electricity through a tube from which nearly all the air had been pumped out. In 1879 Sir William Crookes discovered that peculiar rays were emitted from the negative pole, to which he gave the name "cathode rays." Much later J. J. Thomson and others showed that these rays were negative particles of electricity, or " electrons," each electron weighing about one two- thousandth that of the lightest atom known, namely hydrogen. Then, in 1895, came Rontgen's discovery of the X- rays by impinging the cathode rays on the walls of a glass vessel. The application to medicine of these X-rays was immediately recognised when it was noticed that they could penetrate flesh. Rontgen made the further observation that the X-rays act on photographic plates in their neighborhood. One year later Becquerel, studying the general be- havior of phosphorescent bodies, had occasion to ex- amine the element uranium and its compounds, and these substances gave off rays which resembled the X-rays in their affect on a photographic plate. He further made the extremely important observation that the rays "ionised" the air about them; or, what is the same thing, converted the air about them from an insulator to a conductor of electricity. A gold-leaf electroscope, which had been previously charged with electricity so that its two leaves diverged, was dis- charged with the consequent collapse of the leaves so soon as uranium, or one of its compounds, was brought near it. 160 MARIE SKLODOWSKA CURIE This brings us to Madame Curie's work. Adopting EecquerePs method of detecting the presence of these rays by their action on a gold-leaf electroscope, she made a systematic investigation of various elements and their compounds with the view to finding whether any of them possessed this ray-emitting power. Only one other apart from uranium, namely thorium, was found to possess such a property. But the next observation was a momentous one. Madame Curie noticed that a sample of pitchblende, a mineral from which most of the uranium is extracted, showed an activity which was four to five times as great as the activity produced by the total amount of pure uranium that could be extracted from this sample. There was but one thing to conclude from this, and that was that some other element, more active than uranium, was present in the pitchblende. The work until this point had been done by Madame Curie exclusively. From now on her husband joined her. It required but little calculation to show that the un- known element, if present in the ore, would be there in extremely minute quantity; the importance, therefore, of starting with large quantities of pitchblende in order to extract the element from it was obvious. Through the kindness of the Austrian government, which owned the extensive uranium mines in Joachims- thai, Bohemia, the Curies were presented with one ton of pitchblende from which the uranium had been re- moved. Most of the common, and quite a number of the un- common elements are present in pitchblende, so that the analytical procedure of separating one element from another, and examining each fraction so obtained, is a tedious and difficult one. 161 EMINENT CHEMISTS OF OUR TIME The plan adopted by the Curies was to submit each fraction to the electroscopic examination. Naturally the greater the conductivity, the more active the fraction. In this way a constant and invaluable check on the experi- ments was always at hand. The large quantity of raw material made it necessary to conduct the initial experiments in a factory. The quantities were gradually narrowed down until the test tubes of the laboratory could hold them comfortably. The fraction containing the common element bismuth showed the presence of a powerful radioactive sub- stance, which, after many trials, was partially separated and named polonium, in honor of Madame Curie's native country. Further examination showed that the fraction con- taining the element barium had even more powerful radioactive properties, and by some of the most ex- haustive and painstaking experiments in the history of our science, recalling those of Welsbach on the rare earths, Madame Curie succeeded in separating a salt of barium from the salt of the new element, to which she gave the name of radium. Radium as an element had baffled all attempts at isolation in the pure state until 1910, when our heroine solved this problem, but even the salt of radium showed itself to be two and a half million times as active as uranium! The radiations from radium were shown to ionise air, to act on photographic plates, to change the color of minerals and gems, to impart a deep violet color to the glass tube which contained the radium salt, to convert ordinary oxygen to its more active form, ozone, to pro- duce traces of peroxide of hydrogen in the presence of water, to destroy minute organisms, and to kill cells of skins and produce sores. 162 MARIE SKLODOWSKA CURIE That radium is really a new element, and not some compound or mixture, is proved beyond doubt by the very distinctive spectrum it gives. The wave-lengths of the lines of this spectrum are mathematically con- nected with the spectra given by the elements barium, calcium and strontium, and this relationship, together with its similarity in chemical property to barium, places radium in the class of what are known as alkaline earth metals. The subsequent development of radioactivity has been due to the labors of many workers in many countries. Besides Madame Curie and her husband, one may mention their assistant Debienne, Rutherford, Soddy and Ramsay in England, and Boltwood in America. The value of this work may be gauged by the recog- nition these men have received. Rutherford has lately succeeded J. J. Thomson to the Cavendish Professor- ship of Physics at Cambridge, and Soddy has made rapid jumps from a lectureship at Glasgow University to a professorship at Edinburgh, and within the last few months, to a newly-created chair of chemistry at Oxford. Boltwood has been made director of the chemical depart- ment at Yale University. The reputation of all three rests primarily upon their researches in radioactivity. A brief general account may now be given. Radium gives off three types of rays, and these are distinguished by the Greek letters a, (3, and y. The a-rays have been shown to be atoms of helium which are thrown off with a velocity of thirty thousand kilometers per second, or about one tenth that of light. That helium is one of the products obtained from radium has been shown by the work of Ramsay and Soddy (which see). Unlike the a-particles, which are charged with positive electricity, the g-particles are negatively charged (" elec- ts EMINENT CHEMISTS OF OUR TIME trons "), and are shot out with a velocity equivalent to light. They are identical with Crookes' "cathode rays." A powerful magnetic field will bend the a-rays in one direction and the (3-rays in the opposite direction. The magnet has no effect upon the ^f-rays. These last are identical with the X-rays. The X-rays are further distinguished by their penetrating power. Whereas the a-particles are stopped by a sheet of paper or alumi- nium foil one two-hundred-and-fiftieth of an inch in thickness, and the (3-rays pass through gold-leaf and through aluminium foil up to two-fifths of an inch in thickness, the f-rays penetrate thick layers of metals. The stoppage of these various particles by the air molecules with which they come in contact generates much heat. One of the most remarkable things about this remarkable element is that the temperature around radium is about three degrees higher than the tempera- ture beyond its immediate neighborhood. To put this in another way, radium emits every hour enough heat to raise the temperature of its own weight of water from the temperature of ice to that of the boiling point of water. And what is more amazing still, its heat-gen- erating power seems to be inexhaustible. In 1902 Rutherford and Soddy advanced their " dis- integration " theory, which leads us to believe that the a-particles obtained from radioactive elements such as radium and uranium are due to the disintegration of the atoms of these elements. All subsequent studies have brilliantly confirmed their hypothesis. Whereas chemi- cal changes are changes brought about between atoms, radioactivity results from the changes within the atom, and unlike chemical reactions, we have no known methods of controlling radiactive changes. We cannot start them and we cannot stop them. The temperature 164 MARIE SKLODOWSKA CURIE of the electric arc is as ineffective as a temperature of two hundred degrees below zero. No appliance known to man, no operation known to the scientist, shows any results which our senses can recognise. This opens up a new area which in size to that already explored may be compared to the size of America with reference to the rest of the earth. Indeed, Madame Curie is the Columbus who has discovered another con- tinent in science. For what are the possibilities? In the first place, radium has had a profound influence in modifying our views regarding the structure of matter. Dalton many years ago had postulated in his Atomic Theory that matter is made up of ultimate and indivisible particles which he called atoms. These atoms are active in chemical changes, but even in these changes the atoms do not become subdivided. We still agree with Dalton that chemical changes are brought about by atoms, and that these atoms do not subdivide in the course of such changes, but we can no longer say that the atom is the smallest particle. Far from it. The later researches of J. J. Thomson and others lead us to the belief that each atom is a solar system unto itself, with a positively charged nucleus for its sun, and negatively charged electrons, representing the planets, etc., surrounding it. The radioactivity of the elements thorium, uranium and radium is due to the breaking up of their atoms, with the consequent enormous liberation of energy. Aside from these three, no other element shows any such properties. May it not be possible, then, that in the future some means will be found to cause the atoms of other elements to disintegrate, and thereby to liberate the enormous energy which must be stored in them? Will the energy of the future depend upon this dis- covery? The burning of coal is a chemical change, and EMINENT CHEMISTS OF OUR TIME therefore extra-atomic; will the energy of the future be intra-atomic? One other factor must be touched upon. If a radium salt is heated strongly, or dissolved in water and the water evaporated, the residue seems to show little radio- active power. If this residue be kept for a month it can be shown to have recovered all its lost power. This experiment can be repeated indefinitely. If now the experiment is conducted a little more care- fully, it can be shown that the initial loss of radioactivity is due to the escape of a gas which evolves the rays, in quality and quantity, that the residue has lost. This gas or " emanation " was carefully examined by Ram- say and shown to be a new element belonging to the inert gases of the atmosphere, to which the name of niton was given (see Ramsay). The further interesting fact was brought out that on standing, the " emanation " gradually loses its radio- active power, and its rate of loss is strictly proportional to the rate of gain of radioactive power in the solid radium residue ! The transmutation of one element into another the dream of the alchemists when they wanted to transmute the base metals into gold is an established fact to-day. Radium, we know, breaks up into two other elements, niton and helium ; the niton breaks up still further into a simpler element, and also gives off an atom of helium. 1 1 Recently (June, 1919) Rutherford has performed some experi- ments which lead him to the conclusion that when the element nitrogen is bombarded with a-particles "the atoms arising from the collision . . . are not nitrogen atoms, but probably charged atoms of hydrogen [another element] . . ." The importance to be attached to this observation is that for the first time since the discovery of radioactivity, a method has been devised by which an element may be deliberately converted into another element. Hitherto the ob- served cases of transmutation such as disintegration of radium cited above have been those over which man has so far had no control. * MARIE SKLODOWSKA CURIE The process has been traced experimentally through quite a number of stages, but the peculiar feature of this disintegration process is that at each step an atom of helium is set free. Why just helium? This is one of several puzzles that awaits solution. Coming to more immediate and practical considera- tions, the application of radium in the treatment of a number of diseases, particularly those due to growths, such as cancer, has come to the foreground. Definite cures have not yet been established, but many well- endowed establishments, such as the Crocker Research Institute of New York, and the Radium Institute in Paris, are devoting much time and skill to experimental conditions. Such then is this fascinating study which has led us on our journey from the minutest particles which the eye can see (minute suspensions) to particles which the eye can see only with the help of the most powerful ultra-miscroscope (colloids), and then on to molecules which are formed when a substance like sugar is dis- solved in water, and which never have been seen by mortal eye, and still further to the atoms formed when molecules break up, and yet still further to the electrons which result from the breaking up of atoms, and which in size are one two-thousandth that of the lightest atom known. If astronomy sees the infinitely big in such distances as those from the earth to the nearest fixed star, chemistry and physics approach the infinitely small in comparing the size of man with that of the electron. Madame Curie's pioneer work on radium lasted from 1898 to 1902 some four years. In 1903 the results of her work were presented to the Paris faculty in the form of a thesis for the doctor of science degree. The title page reads, These Presentee a la Faculte des Sciences 167 EMINENT CHEMISTS OF OUR TIME de Paris pour obtenir le grade de Docteur es Sciences physiques. This thesis, unlike Arrhenius's, was received with acclamation. The reason for this is not hard to seek. Arrhenius proposed a novel theory which very few were prepared to understand. Madame Curie, on the other hand, presented the results of experiments on a subject which was engaging the attention of some of the best minds in Europe. The world was prepared for it; the world was not prepared for the theory of electrolytic dissociation. In the history of doctor's dissertations Madame Curie's easily takes first place for importance of contri- bution, with Arrhenius's as a close second; many of the others including even van't Hoff's and Ramsay's have unnecessarily taxed the shelf capacity of our libraries. With a bound Mme. Curie leaped from complete ob- scurity to the center of the world's stage. Unlike most scientific theories or discoveries, radium lent itself freely to sensational newspaper "write-ups," so that this modest little woman was discussed in parallel columns with the prominent politician and the stage beauty. Since natural repugnance for the limelight made it impossible for reporters to get interviews, the imagination came into free play, and a halo of romance and mystery was thrown over her. In the middle ages she might have been a sorceress; now she was a wizard in science. In the same year that is, 1903 Madame Curie and her husband came over to London at the express invita- tion of Lord Kelvin, and Monsieur Curie delivered an address on radium at the Royal Institution. The Curies were presented with the Davy Medal of the Royal Society. How little known the Curies were until about 1903 is shown by the following account, due to Mrs. Hertha Ayrton, herself a distinguished English physicist: "I 168 MARIE SKLODOWSKA CURIE was chatting in the laboratory [in London] one day about the year 1900, when a stranger entered, a Mon- sieur Becquerel, whom I had known previously, and he announced that he had with him a new element, * ra- dium.' He produced a little packet containing a sub- stance which he said was radium bromide. He sub- jected the substance to a chemical test for our informa- tion. Someone asked him who discovered it. He replied, ' Madame Curie of Paris.' This was the first time I had heard of Madame Curie." Within the next few months the Nobel Prize, the highest mark of distinction that can come to any scientist, was divided between the Curies and Becquerel. In the following year Madame Curie was appointed Chef de Travaux, or chief of the laboratory, in the department at the Sorbonne that was especially created for her husband. For two more years were M. and Mme. Curie to live together, loving and working, and living as happily as any man and woman ever have lived. Then one day, early in 1906, after having lunched and chatted with his intimate friend, Professor Perrin, Pierre Curie left him and crossed the Rue Dauphine in Paris " whilst that thoroughfare was, apparently, crowded with vehicles." He was knocked over by one of these vehicles and instantly killed. This terrible accident well nigh resulted in Madame Curie's death. For months her state was such that her friends gave up all hop'e of any recovery. Slowly she found herself again. Her two children and her sci- ence had saved her, and to these she consecrated her life. Langevin, their friend, has this to say of M. and Mme. Curie's marriage : " Cette epoque marque un change- ment profond dans son [Pierre Curie's] existence par son mariage avee Mme. Marie Sklodowska. . . . II est 169 EMINENT CHEMISTS OF OUR TIME difficile, en effet, d'imaginer une union plus intime que celle, plus etroite chaque jour, ou ils eurent tous deux la joie de vivre onze ans. Avec la clarte de son esprit sincere, Curie avait seriti ne pouvoir realiser entiere- ment sa vie que grace a une femme qui fut en meme temps sa collaboratrice. Ce serait une belle chose a laquelle je n'ose croire, ecrivait-il quand il eut trouve celle qu'il esperait de passer la vie Tun pres de Pautre hypnotises dans nos reves." Henri Poincare, as president of the Academie des Sciences, delivered an address on Pierre Curie's life and work in which the following reference was made to the widow: " Dans le deuil ou nous sommes tous plonges, notre pensee va a cette femme admirable qui ne fut pas seulement pour lui une compagne devouee, mais une precieuse collaboratrice." Madame Curie's work on radium has continued with- out a break. In 1910 she, in conjunction with her assistant, Debierne, succeeded in isolating and deter- mining the properties of the metal itself, and radium in the chemical sense was shown to have properties resembling closely those of calcium. In the same year she published her Traite de Radioactivity which covers over a thousand pages, and is the most exhaustive and authoritative work on radium that has thus far been published. With no little pride could Mme. Curie, say in the preface ! " La Radioactivite constitue aujourd'hui une branche importante et independante des sciences physico-chimiques." And this " important and inde- pendent branch of physical chemistry " was originated and developed within the space of fourteen years ! In 1911 Madame Curie was again the recipient of the Nobel Prize, the prize for literature going to Maeter- linck. So far Madame Curie is the only individual who has received the award more than once; this in itself 170 MARIE SKLODOWSKA CURIE speaks volumes as to her standing in the eyes of her fellow-scientists. Prof. E. W. Dahlgren, the president of the Swedish Royal Academy, had this to say in pre- senting Mme. Curie for the award: "This year the Academy has decided to award you the prize for chem- istry for the eminent services you have rendered the science by your discovery of radium and polonium, and by your study of the properties of radium and its isola- tion in the metallic state. . . . Since the inception of the Nobel Prize twelve years ago it is the first time that this distinction has been accorded to a laureate who has already once received the prize. I want you to see, Madame, by this circumstance a proof of the importance which our Academy attaches to your discoveries. . . ." In this same year the French Institute dishonored itself by refusing to elect Madame Curie to member- ship. To the honor of the Academy of Sciences, which is one of the five academies of the French Institute, the representatives of this body placed Mme. Curie at the head of their list of final candidates. This gave rise to a lively discussion on the eligibility of women for member- ship when Mme. Curie's name was brought before the one hundred and fifty Academicians at the quarterly meeting of the five academies. The motion to admit women was finally rejected by 90 to 52, and this august body went on record to the effect that whilst they did not wish to dictate to the separate academies, there was " an immutable tradition against the election of women, which it seemed eminently wise to respect." Science in its search for truth has thrown tradition overboard on innumerable occasions. But it is one thing to defy the " immutable tradition " of man's origin, and another to deny civil rights to his own flesh because of this same " immutable tradition." Such logic diplomatists might envy, and some newspapers applaud, but it can hardly 13 171 EMINENT CHEMISTS OF OUR TIME stand the test of that scientific criticism which these Academicians apply with such telling effect to their scientific work. Shortly before the outbreak of the world war the Univer- sity of Paris undertook the creation of a radium institute for research in radioactivity. This has since been com- pleted and Madame Curie has been placed at its head. The Institute is divided into two departments, the Curie Laboratory, devoted to research in the physics and chemistry of the radioactive elements, and the Pasteur Laboratory, devoted to the application of radioactive sub- stances to medicine. The street has been appropriately renamed the "Rue Pierre Curie." Even during the war this institute was the headquarters for all work in radiology at the French military hospitals, supplying not only the necessary materials, but training apprentices in the methods of application. The French government placed Mme. Curie in absolute charge of all such work. Just now Mme. Curie is supervising the construction of a radium institute in her native city of Warsaw. If Paris is her father Warsaw is her mother. Even after her marriage Madame Curie's struggles were not ended. As late as 1904 the joint income of the Curies was such as to make the simplest life not particularly easy. At that time, we are told, the " dis- mal Boulevard Kellerman " was not the safest of neigh- borhoods, and the Curies, who lived there, were in a section of Paris "inhabited by a class of Russian students of both sexes, who are never favored with invitations to their embassy." The furniture in the modest little house was of the simplest, with all ideas of the aesthetic sacrificed for the useful. Later, when circumstances improved, the Curies acquired a small estate at Fontenay-aux-Roses, near Paris, and here 172 MARIE SKLODOWSKA CURIE Mme. Curie, together with her two children and old Dr. Curie (her late husband's father) lives. " In outward appearance," writes Mrs. Cunningham, " she is tall, just above middle height, broad shouldered and graceful. Her brow is splendid; her lovely grey eyes full of sadness. Her mass of fair hair is wavy, like Paderewski's hair. There is a suggestion of square- ness in her face, very firm mouth and chin, but there is gentleness withal. Her voice is musical, and to her intimate friends she can sometimes be persuaded to recite poetry, which she does, using the tones of her voice with charming inflections. ... In manner she is perfectly simple and unaffected. Like so many Polish women, she has a magnetic personality and an intense love of beauty, for beauty in nature and art. Seeing her one May morning in the classic hall of the Sorbonne, with her long trailing diaphanous draperies, she sug- gested strongly to me a similarity to the old Greek statue of Demetes, the goddess whose face suggests strength and sadness. I would that Rodin thought so too and gave expression to that thought." This description probably reflects a somewhat over- abundant enthusiasm. At any rate, years of grief and ill-health have left their impress upon Mme. Curie. A representative of the Figaro speaks with something nearer the truth when he describes her as " like some- thing washed out, the color gone, the fire extinguished. . . . One is tempted to say her eyes are grey until a closer inspection brings out a trace of blue ; but in the end the hue of these frigid orbs relapses into a sheer neutrality." Her complexion, we are told, is neither pale, nor red, nor sallow, but faded ; her hair is neither auburn, nor brown, nor grey, but neutral. The prominence of the cheek bones bespeaks Polish origin. " Madame 173 EMINENT CHEMISTS OF OUR TIME Curie looks like a person in need of the sun, a person who would benefit from more fresh air." Her voice is low and free from theatricality. Her manner is decidedly cold ; in fact her coldness " suggests the passionless spirit of pure science " a view hardly supported by the few who are her intimates. As a lecturer Mme. Curie is unsurpassed in lucidity of expression, and from the tricks of political oratory she is quite free. Her voice is hardly ever raised beyond the regulated academic level, and her arms, which are long, slender and graceful, are rarely called into play, even when emphasis is sought. Her accent betrays her Polish origin, but she expresses every idea in perfectly idiomatic French. In 1907, one year after her husband's tragic death, and after she had succeeded to the chair which her husband had held at the Sorbonne, Mme. Curie delivered a discourse on polonium, which is still remembered even in fashionable Paris circles of to-day. lord Kelvin, Sir William Ramsay and Sir Oliver Lodge made a special trip from London to hear this great little woman. Even the unfortunate King Carlos of Portugal was attracted. President and Mrs. Fallieres headed a crowd which was representative of the wealth, fashion and cosmopolitan- ism of the gay capital of France. " On the stroke of three an insignificant little black-robed woman 1 stepped in, and the vast and brilliant throng rose with a thrill of homage and respect. The next moment a roar of applause burst forth. The timid little figure was visibly distressed, and raised a trembling hand in mute appeal. Then you could have heard a pin drop, and she began to speak." Mme. Curie may be the great scientist, but she has many of the traits of feminity and motherhood which 1 Mrs. Cunningham, saturated with a reporter's romance, de- scribes Mme. Curie as "tall, just above middle height." ] MARIE SKLODOWSKA CURIE most men of all ages have admired. Aside from her work, her attention is devoted almost exclusively to the welfare of her two daughters, Irene and Eve, seventeen and thirteen years old respectively. Irene cares little for science, but much for music and the arts, but little Eve is all for laboratory work. Already to-day she assists her mother in much the same way that Madame Curie, years ago, assisted her father in Warsaw. When the two children were younger Mme. Curie made all their dresses, and washed and ironed the more delicate pieces of lingerie. In so far as she herself is concerned, Mme. Curie gives little thought to her own appearance. She is excessively neat, as becomes the nature of her work, but her dress is of the simplest, which changes not when fashion changes. The first and only time that " Madame " indulged in a decottetee silk dress was when she was invited to dinner by Presi- dent and Mrs. Loubet. Gossip has it that this " fancy " dress has serve ' ; as useful a purpose as the young lady's customary wedding gown. Mme. Curie's sister, Dr. Dluska, 2 has charge of a sanitarium at Zakopane, a famous retreat in the Car- pathians, and there, in days gone by, Sienkiewicz, Paderewski and Mme. Curie spent their summers, dreaming of the rebirth of a nation. Jescza Polska nie zginela (Poland is not yet lost) runs the first line of Poland's national song. Mme. Curie continues to spend her summers at Zakopana ; one of the other two is dead ; and the third has just retired from the presidency of * Mme. Curie also has a brother, Dr. Sklodowski, who practices medicine in Warsaw. Lest the reader be somewhat confused, we hasten to add that " ski " is the masculine, and " ska " the fem- inine ending in Polish; hence Mile. Marie Sklodowska. The rumors that the Sklodowski family is of Jewish origin are not true. 175 EMINENT CHEMISTS OF OUR TIME the old-new country whose chief glory is that it has given birth to Marie Sklodowska Curie. References Part of the material for this biography has been obtained from private sources. Miss Cunningham's account (i) has good personal touches but is quite worthless scientifically. The same may be said of the articles by Emily Crawford (2) and W. G. Fitzgerald (3). Some sidelights on Madame Curie are given by Paul Langevin (4) in his account of Pierre Curie. For a lay- man desirous of an intelligent description of radium and its significance, Soddy's Matter and Energy (5) stands alone in the English language. A more technical ac- count may be found in Rutherford's article prepared for the nth edition of the Britanica (6). The beginner in inorganic chemistry can hardly do better than consult Smith's Introduction (7). The more comprehensive works of Soddy (8), Rutherford (9), and Curie (10) are the standard reference books. 1. Marian Cunningham: Madame Curie (Sklodowska) and the Story of Radium (Saint Catherine Press, London). 2. Emily Crawford: The Curies at Home. The World To-day, 6, 490 (1904). 3. W. G. Fitzgerald: Madame Curie and her Work. Harper's Bazaar, 42, 233 (1908). 4. Paul Langevin: Piere Curie. La Revue du Mois, 2 t 5 (1906). 5. F. Soddy: Matter and Energy (Henry Holt and Co.). 6. Ernest Rutherford: Radioactivity [Encycl. Britannica, 22, 794 (1911)]. 7. Alexander Smith: Introduction to Inorganic Chemistry (Century Co. 1917). 8. F. Soddy: The Chemistry of the Radio-Elements (Longmans, Green, and Co. 1915). 9. Ernest Rutherford: Radioactive Substances and their Radia- tions (Cambridge University Press. 1913). 10. Marie Curie: TraitS de RadioactivitS (Gauthier-Villars, Im- primeur-Libraire, Paris. 1910). 176 VICTOR MEYER CTOR MEYER belongs to the school of pure organic chemists to the period when organic chemistry was in its ascendency. He easily takes his place among the fore- most pioneers in this phase of the science. He began work when the superstructure of organic chemistry had yet to be built up, and in this building process few can claim the share he can. When the beauty and sym- metry of the building was all but apparent Meyer passed away. The man of forty-nine (he had reached that age when he took his own life), with the rare mind that was his, could still have accomplished much. Meyer was born in Berlin on September 8, 1848. His father, a prosperous Jewish merchant and a man of high intelligence, surrounded himself with the elite of the intellectual element of the city. The chemist Sonnen- schein, then a privat-docent at the University; Bern- stein, the founder and editor of the Volkszeitung; Franz Duncker, Love-Kalbe, Major Beitzke (author of the "Thirty Years' War") Schulze-Delitzsch and Berthold Auerbach were frequent visitors to the house. It was in such an atmosphere that Victor Meyer was brought up. Together with his brother, Victor received his earliest instruction from his mother. Later a private tutor pre- pared the children for the gymnasium, and this Victor entered when he was ten years old. During these early years at the gymnasium, Meyer's leanings were rather towards literature than science. The drama especially had a strong attraction for him. 177 EMINENT CHEMISTS OF OUR TIME Indeed, at fifteen, the boy had quite made up his mind to become an actor. To his father's remonstrances, who watched these developments with much perturbation, Victor replied: " Never can I become anything else never ! I feel it. In any other profession I shall remain a good-for-nothing the rest of my life." However, in the meantime the lad continued his academic studies, and in the spring of 1865 he passed his matriculation examination (Abiturientenexameri). Hoping against hope that possibly the university at- mosphere would tend to direct Victor's thoughts in another direction, the family persuaded the youth to proceed to Heidelberg, there to attend some lectures in the company of his elder brother. What the incessant arguments of the parents and friends had failed to do, the chemical lectures of one of the professors easily accomplished. In Bunsen the young man encountered one of those rare minds who can see and demonstrate the beauty and poetry of anything they happen to be engaged in. From the lips of Bunsen chemistry issued forth as a song to nature, and as a song to nature Meyer caught the refrain. Small, and quite childish in appearance, the seventeen- year-old boy enrolled as a student of the university. During the first semester he attended Hofmann's lec- tures in Berlin, so as to be near his parents. After that he took up his abode in Heidelberg. Here he followed Kirchhoff's lectures on physics, Kopp's on theoretical chemistry, Helmholtz's on physiology, Erlenmeyer's on organic chemistry, and Bunsen's on general chem- istry truly as illustrious a band of scholars as could be found anywhere. Under the same roof there lived Julius Bernstein (the son of the family's old friend), who was at that time one of Helmholtz's assistants, and who, as professor of VICTOR MEYER physiology at Halle, has since risen to be one of Ger- many's great physiologists. Bernstein and the Meyers fraternized much together. To this trio there was later added a fourth Paul du Bois Reymond, then privat-docent in mathematics. Meyer's work at the university was brilliant in the extreme : he headed the lists in every course. In May, 1867, when but nineteen years old, he received the doctor's degree summa cum laude which is given on but rare occasions. Bunsen immediately appointed him to an assistantship, and here he chiefly busied himself with analyses of various spring waters by methods initi- ated or improved by Bunsen and his pupils. In addition to his work at the laboratory, Meyer was much in demand as a coach for the doctor's examination. Yet he found tune to cultivate his artistic tastes in many ways. From his earliest days he played the violin; now he began to take lessons in piano playing. The classics he assiduously cultivated, and never missed an opportunity of attending the more notable performances at Mannheim. His week ends were usually spent wandering near Heidelberg. Julius Bernstein, who often accompanied him on these excursions, tells of a pretty little incident that occurred to them on one occa- sion: /" Towards evening, tired and weary after a day's tramping, we entered a wine cellar, and there sat down at one of the tables. A young peasant who happened to come in came up to us and asked permission to sit at our table. As we were chatting with him he fixed his eyes on Victor, stared at him for some time, and then exclaimed, ' See here, never in my lif e have I seen such a handsome fellow as you are.' Just quite in this way Victor was hardly ever addressed again, but it is a fact that the ladies were all more or less in love with him." 179 EMINENT CHEMISTS OF OUR TIME In the late sixties Baeyer had already established a reputation such as to attract students from all parts of the world, and it was to Baeyer's laboratory in Berlin (at the Gewerbeakademie) that Meyer proceeded in 1868. And what a busy and profitable place this proved to be! Baeyer himself had already begun his classic researches on indigo blue. Graebe and Liebermann had just produced alizarin artificially the first instance of the synthesis of a plant-coloring matter. S. Marasse, B. Jaffe, E. Ludwig and W. A. van Dorp were all helping to make the laboratory famous. I The young Meyer made more than a favorable im- pression, according to Liebermann's testimony: " Mey- er's remarkable ability could hardly pass unnoticed. His congenial personality added but to the esteem in which he was held. He seemed to have read every- thing, and his memory was simply phenomenal. . . . Many obscure references that at that time were rather difficult to locate could easily be traced by consulting Meyer. He could usually tell you not merely the volume but the very page." During the three years that Meyer remained here he published several important papers, among which may be mentioned his contributions to the constitu- tion of camphor, of chloral hydrate and of the benzene ring. Towards the end of 1870, at Baeyer's recommenda- tion, Meyer was appointed professor extraordinary at the Stuttgart Polytechnik, of the chemical laboratory of which H. v. Fehling was the director. Here the twenty- three-year-old professor, who had never been privat- docent, was put in charge of the organic chemistry department. Stuttgart proved an incentive to renewed activity. Here he announced his discovery of the nitro compounds 180 VICTOR MEYER of the aliphatic series his first really lasting contri- bution to the advancement of the science. Though little burdened with routine at Stuttgart, Meyer was sorely tempted to accept a first assistantship at the University of Strassburg, offered him by Baeyer, who was about to take charge of the chemical institute there. On the one hand, there was the opportunity of once again coming in contact with the great master mind; on the other hand, he was to be put in charge of the analytical department, and this meant running around the laboratory and attending to the wants of the students the greater part of the day. In Stuttgart he therefore remained till one day President Kappeler, of the Zurich Polytechnik, chanced to walk into his lecture-room. Kappeler was so impressed with the young man's ability that he immediately offered Meyer the vacant professorship of chemistry at Zurich. And so at twenty-four Victor became a full-fledged professor ordinarius! This appointment Meyer celebrated in a highly appro- priate way: he became engaged to the companion of his youth, Fraulein Hedwig Davidson. The Zurich laboratory was divided into two parts, the analytical and the technical, and of the former Meyer had charge. His predecessor was Wislecenus, who had accepted a call to Leipzig. Bolley had control of the technicological side. With Bolley, as well as with Eduard Schar, the professor of pharmacy, and Ernst Schulze, the professor of agricultural chemistry, the newly-appointed instructor fraternized much. The re- searches that had been started at Stuttgart were now renewed with the utmost vigor. In the beginning all did not go well. A mercury compound of nitromethane which Rilliet, his private assistant, had prepared, ex- ploded, with serious injury to Rilliet. Wurster was 181 EMINENT CHEMISTS OF OUR TIME brought from Stuttgart to replace him, and Meyer found him a competent substitute. " I have given him rooms in the laboratory," he writes; "this is of the utmost importance, as thereby he can do twice as much work. He is very conscientious so much so, that I think I shall send for another one of my Stuttgart pupils." Satisfied as he was with the assistants he imported, Meyer was far from satisfied with the assistants he found, or with the cool reception accorded him by the students. In Stuttgart he was the idol of his pupils; here the men had little sympathy with one so much taken up with the theoretical aspect of the subject. || " One single publi- cation on some cheese preparation makes one far more celebrated in Switzerland than one thousand discoveries in the field of pure organic chemistry," he writes bitterly. But the day was to come when the Swiss were to vener- ate him, and the day was also to come when Meyer would love his Zurich students and the Zurich atmosphere. From the very first he had his hands full. "I am very busy," he writes, " as you can conclude from the following: I devote eight hours to lectures in organic chemistry, two to lectures on analytical chemistry, two to metallurgy (in place of Kopp, who is in Vienna), and besides this I have to superintend Kopp's as well as my own laboratory." But this did not prevent him from pursuing his research work. In the month of July he records the synthesis of jiphejiyl-me thane from benzoyl alcohol and benzene. This compound, wEich melts at 26 C., Meyer placed on his writing table, and used it in place of a thermometer. At ten in the morning, if the substance was in a molten state, the Herr Professor would announce that weather conditions made it im- practicable to pursue any work in the laboratory; and then professor and students would go bathing. On one 182 V. Meyer's apparatus for determining the vapor density, a factor of extreme importance in deducing the constitution of compounds, [Reproduced from the Berichte der deutschen chsmischen Gesettschaft.] VICTOR MEYER of these occasions Meyer rescued one of his assistants, Michler, from drowning. But recreation played but a small part in the Zurich life. Apart from the regular students there were (in 1876) twelve men working for their doctorate, in addi- tion to Meyer's four assistants, who had already passed that stage, but who were busier than any of the candi- dates creating new compounds. The nitro compounds of the aliphatic series, the first piece of classical research with which the name of Meyer is associated, were en- gaging the attention of the youthful professor; but even at that time he made excursions into the realm of indigo chemistry (the artificial production of which he hoped to solve in one week!) and discussed van't HofFs views on optical activity and the asymmetry of the carbon atom. With Baeyer, the great master, and with Graebe and Liebermann, Meyer carried on a brisk correspondence, the letters dealing chiefly with views on current scientific topics. In 1876 his elder brother obtained a position near Zurich and Victor's delight knew no bounds. Gustav Cohn, the economist, and Eduard Hitzig, the psychiatrist, were about this time appointed professors at the University. Graebe himself, who had been in delicate health, resigned from his Konigsberg position and came to Zurich to join the happy crowd. But for a rather unpleasant polemic with Ladenburg (Meyer later dubbed this episode the Ladenburg-Fieber) which tended to undermine Meyer's delicate constitution, there was nothing at this time to mar the even tenor of the young man's life. He had just begun his second classical work : his method of determining vapor density. We find him writing to Baeyer asking for some methyl anthracene, a substance which by analysis can hardly be differentiated from ordinary anthracene, but which can easily be identified by the vapor density method. 183 EMINENT CHEMISTS OF OUR TIME In the spring of 1876 Meyer received a call from the Konigsberg authorities, but by this time he had come to like Zurich and was loath to leave it. As an inducement to remain, and in appreciation of his services, Kappeler had Meyer's salary increased by 1500 francs a year. Not so very long after this a vacancy occurred in Er- langen. The rumor had gone forth that Meyer would be offered the position, and this came to the ears of the president. Without waiting to hear from Meyer, Kap- peler took the initiative by informing him that the wish of the governing body to have him remain in Zurich was so earnest that they were willing to make his position tenable for life, provided he would decide to stay (Meyer held it on a ten-year contract), and that they would further increase his salary by 1000 francs. " As I had no desire to go to Erlangen," Meyer writes to Baeyer, " I gave him the assurance with pleasure." The miscarriage of one of his experiments before the student class made him hit upon what is conceded to be his most brilliant discovery thiophene. "The analy- ses," he writes to Baeyer, " have shown the compound to have the formula C 4 H 4 S. It boils at 84 C. How should it be named? Kindly help me. I do not like such a name as thiofurfuran. . . . How about indogen? ... or indophenin? or thiochrom, krytan, kryptophan? I would like to get hold of a name that would please you, too. Possibly the Frau Professor would like to take part in this." Thiophene was the name finally selected, and this became the mother substance of a group of compounds almost as extensive as benzene it self, which the genius of Meyer introduced into organic chemistry. In January, 1884, in the company of Professor Blunt- schli, the architect, Meyer undertook a journey through Austria-Hungary, with the view to examining the various 184 VICTOR MEYER chemical laboratories there. Their journey lay over Munich, and here the first stop was made. " We have already been in Munich and Graetz," he writes " and in both places we had a most delightful tune. In Munich I spent a lovely time with Baeyer, Otto Fischer and Konig, and one delightful musical afternoon with the Heyses." (Here he refers to Heyse, the poet and novelist.) Again: " The new buildings in Vienna defy description. The Parliament, the Guildhall, the Uni- versity and the Hofburg Theatre constitute a section beside which the Place de la Concorde in Paris fades into insignificance. In addition, they have the recently- constructed museums by Semper, which are the finest examples of Renaissance architecture. I witnessed a performance of the Walkure and the second part of Faust. I also saw my old flame, the actress Lucca. You can imagine how happy I was to see her again after thirteen years of absence. She is as beautiful as ever, time not seeming to have altered her." In July, 1884, Hubner, the Gottingen professor, died. Meyer's friend Klein, who informed him of this, also told him that he was a likely candidate. The thought of having to leave Zurich was quite unbearable. What had he not accomplished during these thirteen never-to-be forgotten years! But, then, to step into the world- famed Gottingen school that had also to be considered. Meyer had not yet reached his thirty-sixth year. He had to regard the call to Wohler's old establishment as the highest compliment that could be paid to him. Indeed, the compliment proved a higher one than even he expected, for none others were even to be considered. During the last days of the year 1889 Meyer proceeded to Bonn to undergo an energetic cure : a sort of massage and electrical treatment combined. He writes: "For fourteen days I lived in the strictest incognito, going 14 185 EMINENT CHEMISTS OF OUR TIME under the name of Professor Meyer, of Berlin. Since a week ago I have given this up and am now with Wallach and Kekule daily. To see Kekule once again and to speak to him does one's heart good. You will not con- sider me vain when I tell you that it was delightful to hear him say to me that he considered me the foremost among the chemists of the younger generation. Wallach is a splendid type of fellow. He visits me daily. He has no easy life of it. What a pity that he cannot go to Zurich! I suppose you have heard that Hantzsch has been nominated to succeed me. I am glad to see that both Kekule and Wallach approve Kappeler's choice. Wallach has completed a wonderful piece of work on the terpenes which must surely become epoch-making." Meyer left Bonn in indifferent health and after a short stay hi Zurich proceeded to the Riviera with his parents. Here he felt himself slightly better, but not very much so. |" Italy and the Riviera are very nice, but only for the one who is in a position to enjoy her beauties," he writes. " In my case, where I dare not go beyond one-half hour's distance from the house, the mountains call in vain." In this condition Meyer proceeded to Gottingen. He was comforted to a large extent in that his excellent assistant, Sandmeyer, accompanied him for the summer semester. Sandmeyer, one of Meyer's " discoveries," is to-day known wherever chemistry flourishes. He started as a mechanic in Meyer's laboratory, but soon gave this up to devote all his time to chemistry. Meyer left Zurich without being able to take leave of his students, but some months later he returned to attend the seventieth birthday of Kappeler. At the Kommers, which was given in the old man's honor, Meyer was among the speakers. / Professor Gold- schmidt thus describes the scene : '>! see him (Meyer) 186 VICTOR MEYER even now before me as he spoke to the students at the Kommers in the evening. The 'Zuricher Polytech- nikers ' have, as a rule, but little opportunity of knowing the professors outside their special faculty, and have therefore but little interest in those who are not their own teachers. As Victor Meyer's slender form ap- peared on the platform, and as his bright blue eyes glanced around the assembly, there broke forth a shout of welcome from all engineers, machinists, architects, as well as from his own students, the chemists to be ended in a whirlwind of applause at the close of a speech, sparkling and witty as ever." Meyer's reception in Gottingen was all that could be desired. His inaugural lecture created a furore (" es war zum Brechen voll," he writes), and he was well pleased with so auspicious a beginning. Besides, the other men on the staff were such as any head of a depart- ment could well be proud of. C. Polstorff, K. Buchka, R. Leuckardt, P. Jannasch, and L. Gattermann were among the regular forces. Then there was the old attendant Mahlmann, whom the students of Wohler still remembered as a marvel in glass blowing. And, finally, Sandmeyer, Stadler, and several other Zurich men completed the list. The scientific work inaugurated here was in the main a continuation of what had previously been started else- where. That wonderful thiophene, which seemed to be the starting point for as many derivatives as benzene itself, was still a keen subject for study in his labor- atory. The material along these lines accumulated to such an extent that Meyer found himself warranted in publishing a book on these sulphur compounds. Vapor density determinations a subject which had agitated ) him even early in his Zurich career were being fol- lowed up with unslackened zeal. 187 EMINENT CHEMISTS OF OUR TIME But Meyer was never so engrossed with his own work as not to keep abreast of the work which others in the field were doing. Thus we find him engaging in a friendly polemic with Baeyer on the latter 's views as to the constitution of benzene. Stereoisomerism a term corned by Meyer dealing with configuration in space, a subject then in its infancy, also engaged his attention; and he early applied van't Hoff's views to explain several perplexities, such as the configuration of hydroxylamine and isomeric oximes of unsymmetrical ketones. Here we see the Professor no less proficient in the field of speculation than in that of experimentation. Feeling the need of a comprehensive treatise on organic chemistry, which neither the German nor any other language supplied, Meyer, in collaboration with his assistant Jacobson, started his famous text-book. To this day it has not a peer. Those who have had occasion to do any extensive work in this branch of the science know well enough how indispensable a part of their equipment this book is. Unfortunately the senior author did not live long enough to see the work in its completed form (it ultimately appeared still incom- plete in two bulky volumes). Much as the nature and extent of the research work adds to the renown of an institution, certain other factors tend to have no small influence. When Meyer came to Gottingen the size and equipment of the laboratories were far from what could be desired, and one of his stipulations was that this state of affairs would soon be altered. With a willingness which could result only from the esteem in which Meyer was held, the author- ities appropriated a sum sufficient to build a new labor- atory, and gave him complete charge of supervising its construction. Of course, this took up much time, but as the laboratory was to prove the tools of the carpenter, 188 VICTOR MEYER and realizing how much the finished product is de- pendent upon the quality of the tools employed, Meyer threw himself into it with a wholeheartedness which was characteristic of everything he undertook. Another step in the direction of increasing efficiency was the formation of the Gb'ttingen Chemical Society. The number of research men had risen to such a height at this time there were 105 that Meyer readily fore- saw the advantage of organizing a club where these men could congregate and discuss current topics. At these meetings the students would give accounts of the progress of their latest investigations, and professors and students would engage in friendly criticism. The esprit de corps thus created was little short of wonderful. The one source of great worry to Meyer as well as to his dear friends was the state of his health, which at best was but indifferent. Here in Gottingen he had formed a very intimate friendship with Ebstein, a well- I known professor in the medical faculty, and, fortunately ! for him, Ebstein was untiring in his efforts. In 1888, when Meyer suffered a bad attack of diphtheria, only his friend's constant attention saved him. Ebstein pre- i scribed no end of rest cures. These were well enough in themselves, but, as they so often clashed with work in the laboratory, Meyer fretted not a little. However, feeling that it was a question of life and death, he usually : yielded. It was on one of these recuperation tours that Meyer revisited his old Zurich. His reception by faculty and students left no doubt as to the way they regarded their old professor. But he had already had a proof of this shortly after he came to Gottingen. Then his Zurich scholars sent him an address which he described as j"so etwas schones habe ich noch nicht gelesen und auch noch nicht gesehen ! " 189 EMINENT CHEMISTS OF OUR TIME The summer vacations were usually spent in Heligo- land by the sea. Here, in company with his friends, Liebermann, Tollens, Ebstein, and occasionally Kirch- hoff, the weeks were passed in recuperation and inter- change of views. In the fall of 1888 his quiet life gave place to days of great agitation. On November u he writes to his brother: " Con- fidential! Yesterday I received an official communi- cation from the ministry offering me the professorship hi Heidelberg in succession to Bunsen. They are ready to do anything I want them to do. But not a soul must know of this till next Thursday. On that day the new chemical building will be officially opened, and were this news to leak out then, it would cause a great scandal. What shall I do, unlucky man that I am! The greatest piece of good fortune hi the world, and yet here I am a most dissatisfied beggar." To Baeyer he writes: " I must write to you in the very first place. I am not far wrong when I surmise that you have had a great deal to do with the honor that has come to me. My debt of gratitude to you is forever on the increase. The Minister of Education writes that the Faculty and Senate have nominated me unico /oco, and that Bunsen was particularly desirous of seeing me succeed him." In Berlin, where negotiations were begun, Althoff, the minister, was as bent upon retaining Meyer at least in Prussia as the Heidelberg authorities were bent upon getting him. He held out the assurance that Meyer would be the logical successor to Hofmann hi Berlin, as Helmholtz and the majority of the faculty there had declared themselves in his favor. " I brushed all this aside," writes Meyer, " and told Althoff that I hoped Hofmann would write a nice obituary notice of me in the Berichte." Not even the title of Geheimrat, which 190 VICTOR MEYER was bestowed upon him at this time, could influence him. " On the envelope you address me as Geheimrat," he writes to his brother. "That, of course doesn't matter, and yet it troubles me. I have strictly forbidden any of my assistants to apply that title to me. ' Pro- fessor' is far more to my liking, and that they shall call me, as they have hitherto done." Urged by Bunsen, Meyer finally decided for Heidel- berg. " I am the happiest and yet the most wretched of men," he writes. Before proceeding to assume his duties in Heidelberg he spent several delightful days in Bordighera. Here were Baeyer, Emil Fischer, Wallach and Quincke, " the masters of- them that know " in chemistry. To Heidelberg Meyer took as his assistants Jannasch, Gattermann, Jacobson, Auwers and Demuth. At this day when one reads these names one cannot but help admiring Meyer's wonderful judgment of men. Every one of these five has since made an enviable name for himself. "I saw him in Heidelberg in the spring of 1891," writes Thorpe, " when he was busy with the enlarge- ment of the old laboratory, and it was with a glance of pride a pardonable pride that he pointed out the places where he and I had worked with * Papa ' Bun- sen. ... It was strange, too, to hear the sound of children's voices and their laughter, and the bustle of servants in what was formerly the silent, half-deserted rooms overlooking the Wredeplatz; and stranger still to me was it, as we together called upon Bunsen, sitting solitarily in his rooms overlooking the Bunsenstrasse, to behold the meeting and to listen to the greeting of these two men the memory of whose names and fame Heidelberg will cherish so long as Heidelberg exists." 191 EMINENT CHEMISTS OF OUR TIME At forty-one Meyer found himself head of what then was the most famous chemical school in the world. For many years Bunsen had been looked upon as the Nestor -of the science. The most promising students all flocked to Heidelberg to sit at the feet of the great master. Almost every university chair of chemistry of any pretensions was filled by one of Bunsen's pupils. Yet of all of them Bunsen looked upon Meyer as the most brilliant, and it was because of that that he was so eager to have Meyer succeed him. As in Gb'ttingen so in Heidelberg, Meyer continued researches long before begun. These were, however, supplemented by one important addition: a study of conditions determining both the gradual and explosive combustion of gaseous mixtures, and this new phase of his labors may be regarded as the outstanding feature of his Heidelberg tenure of office. All would have been well but for his physical suffer- ings. These re-commenced soon after he came to Heidelberg, and they scarcely left him till the day of his death. Early in the morning of August 8, 1897, ^ e took his own life by swallowing some prussic acid. On the table he left this message: " Geliebte Frau! Geliebte Kinder! Lebt wohl! Meine Nerven sind zerstort, ich kann nicht mehr." At the early age of forty-nine, when in the full bloom of his powers, this remarkably gifted man passed away. From the reports which have come to us it would seem that Meyer's qualities as a teacher were rivalled only by his powers as an investigator. Mention has already been made of his histrionic talents; these were put to effective use hi later days as professor. His extraordinary command of language, spoken in a well- 192 VICTOR MEYER modulated voice, and coupled with a well-nigh unrivalled knowledge of his subject, went far to assure success. In addition, Meyer's laboratory technique, one of his precious assets, stood him in excellent stead when experimentally illustrating his lectures and his lectures were always copiously illustrated by experiments, in the preparation of which no pains were spared. 1 Nor as a man did he fall short. Sympathetic by nature, generous almost to a fault, always eager to acknowledge the labor of others, with not a taint of jealousy in his make-up, full of a hearty optimism which made him a congenial companion, a splendid raconteur, an excellent after-dinner speaker, a violin-player of no mean calibre these qualities endeared him to all. His friends, Bunsen, Kopp, Erlenmeyer, Baeyer, Graebe, Kekule, Liebermann, Fischer, etc., respected him not only as an eminent colleague, but loved him as a man of worth. 2 His house was a centre not merely for scientific, but literary and artistic notables. At these gatherings his 1 " I well recollect that the word most frequently used in Zurich in defining the opinions of Victor Meyer's students of his lectures was 'brilliant I* (Watson Smith). "What particularly struck me about his lectures was their finished style. He made fairly constant use of notes, speaking with great rapidity. Yet his treat- ment of the subject was very clear, and his language perfect. The experiments were always well prepared and exceptionally success- ful. Indeed, his lectures were most popular. ..." (John I. Watts.) 2 " Ich muss Euch doch sagen, wie entziickt ich wider von allem bin: Berlin, Halle, Miinchen. In Miinchen war es ganz herrlich mit Baeyers, Fischers, und dem anderen. Baeyer ergriff eimnal bei Tische das Glas um mit Emil Fishcer und mir Schmollis zu machen, denkt nur, der liebe Mann! Es brachte uns momentan in fSrmliche Verlegenheit, denn naturlich brauchten wir mehrere Tage, bis wir uns daran gewb'hnen konnten, ihn ungeniert Du zu nennen." (Victor Meyer, in a letter to his brother, October 17, 1883.) 193 EMINENT CHEMISTS OF OUR TIME charming wife and four daughters did much to con- tribute towards a delightful evening. 8 Meyer was not one of those professors who shrink from popularizing their science. He frequently wrote for the Naturforcher, Naturwissenschaftliche Rundschau, Deutsche Revue, Deutsche Worte. Even in Harden's Zukunft we find an article on Pasteur in which the attempt is made to explain the asymmetry of the carbon atom to a lay public. Nor were his activities strictly con- fined to scientific subjects. In pure belles-lettres he published Wanderblattern und Skizzen Aus Natur und Wissenschaft and Martztage im Kanarischen Archipel. At the time of his death Meyer was president of the German chemical society, Emil Fischer being the vice- president. In 1888, when the new building at Gottingen was finished, the title of Geheimrath was bestowed on him. He was also a member of the Akademien der Wissenschaften zu Berlin, Munchen; die Gesellschaft der Wissenschaften zu Upsala, and Gottinger Gelehrte Gesellschaft. From the Royal Society of London he received the Davy Medal, and the University of Kb'nigs- berg granted him the degree M.D. (Hon.X 3 " Die jugendliche Gestallt, der fein geschmttene, geistreiche Kopf, das seelenvolle blaue Auge, der Wohlklang der Stimme nah- men schon ausserlich Jeden fur ihn ein." (Liebermann.) " Young, handsome, well dressed for a German professor with a quick wit and a genial manner, he was a welcome addition to any gathering.'; (John I. Watts.) " No one was more popular at these gatherings (the Chemical Society at Heidelberg) than Meyer. His nimbje mind and retentive memory, his gift of ready speech, his sense of humor, and genial manner combined to make it pleasant to listen to him, no matter whether he was, in accordance with the rules of the society, called upon to give an account of some work which had just been published, or whether he was discussing and criticising a communication from a fellow-member." (Thorpe.) 194 VICTOR MEYER References For much of my material I am indebted to Richard Meyer's life of his brother (i). Carl Liebermann's memorial lecture (2) delivered to the members of the German chemical society is a beautiful homage to a departed friend. Prof. . Thorpe in his Essays on Historical Chemistry (3) has an interesting article on Victor Meyer. A detailed accound of Meyer's work will be found in Dr. Harrow's article (4). z. Richard Meyer: Victor Meyer. Berichte der deutchen chem- ischen Gesellschaft (Berlin), 41, 4505 (1908). a. Carl Liebermann: Victor Meyer. Berichte der deutchen chem- ischen Gesellschaft (Berlin), 30, 2157 (1897). 3. E. Thorpe: Essays on Historical Chemistry (Macmillan and Co. 19"). 4. Benjamin Harrow: Victor Meyer His Life and Work. Journal of the Franklin Institute , Sept. (1916), p. 377. 195 IRA REMSEN MISTRY in America is a very young product. It probably received its impetus from the Englishman, Priestly, the discoverer of oxygen, who came to these shores towards the close of the eighteenth century, and from Robert Hare, the inventor of the oxy-hydrogen blowpipe. Indirectly, the illustrious Benjamin Franklin also had a share in laying foundations. The flame was kept a-burning by a number of well- known teachers at various university centers in the country, such as Wolcott Gibbs (1822-1908) and J. S. Cooke (1827-94) of Harvard, S. W. Johnson (1830- 1909) of Yale, and J. W. Mallet (1832-1912), of Virginia. The more modern period was ushered in by Charles Eliot in Boston, Frederick Chandler, at Columbia E. F. Smith at Pennsylvania, and Ira Remsen at Johns Hopkins. From small beginnings, the science has enlarged a thousand fold. The American Chemical Society has a membership of 13,000. It publishes an erudite journal, devoted to recording the results of research by its members; a chemical abstracts, embracing a digest of the world's chemical literature; and a journal of in- dustrial chemistry which, in the last four or five years, has become one of the best in the world. Remsen was the first professor of chemistry at the first institution ever established in America for post- graduate work Johns Hopkins. He was the founder of the American Chemical Journal, the first of its kind in America. As teacher, as research worker and as 197 EMINENT CHEMISTS OF OUR TIME writer, he is probably more directly responsible for the remarkable development of the science in the United States than any other man living. Remsen was born in New York City on February 10, 1846. His father, James Vanderbilt Remsen, was descended from one of the earliest Dutch settlers of Long Island. His mother, Rosanna Secor Remsen, could also trace her descent from early Dutch settlers and French Hugenots. Her grandfather was the Rev. James D. Demarest of the Dutch Reformed Church, who had married Eliza Haring, daughter of John Haring, a man of some distinction in Revolutionary times. In the house of the Rev. Demarest, where Remsen spent part of his childhood, both Dutch and English were spoken; the clergyman, in fact, preached in both these languages. The atmosphere was a deeply re- ligious one. There were morning and evening prayers and reading of the scriptures, and rather long grace before and after each meal. Before he was twelve Remsen had read the Bible several tunes, and fervently believed every line written in the holy book. To improve his wife's health, Remsen senior bought a farm in Rockland County, New York, and Ira was brought here when some eight years old. The next two years were spent in the country, giving the boy an oppor- tunity to come into close contact with nature a most valuable education for any boy. Trees and birds and fruits and flowers and animals and various aspects of farming, all came under his survey. After his mother's death young Remsen and the rest of the family returned to New York. The smattering of knowledge which the boy had received in rural schools was now augmented by first sending him to the public school, and later, when fourteen old, to the Free Academy, now the College of the City of New York. 198 IRA REMSEN With the exception of history, Remsen excelled in all subjects at the College, particularly in mathematics. The highly suggestive way of teaching history was to cram dates down your throat: if they refused to stick, you were a poor student of history. Remsen had no memory for dates, and so he was adjudged a poor student of history. Latin and Greek were also pumped into his poor little system, to which, strangely enough, Remsen took very kindly. Of science there was precious little. Dr. Ogden Doremus embraced the whole of science, anatomy, physiology, geology, astronomy, etc., in 3 course of lectures given once a week during the year. Prof. Wolcott Gibbs, later at Harvard, did give a few lectures on chemistry, but these made no impression upon Remsen. What helped considerably were Dore- mus's popular lectures on physics and chemistry, given in the large lecture hall of the Cooper Institute. Doremus never spared experiments, and thereby he aroused interest in many of his hearers, among them Remsen. Remsen never graduated from the Free Academy. His father had decided that the lad should study medi- cine, and in the opinion of this good man, as well as in that of the family physician, the earlier Ira was started upon his medical career, the better. That the boy had shown no aptitude along this line mattered little. In those days parents did not consult children, and children were obedient. Remsen was apprenticed to a medical man who taught chemistry in the homeopathic medical college. That worthy man gave the boy a text-book of chemistry, and said, "Read I" So read he did. But it was Greek to him worse than Greek, for he knew something of that language. Years later, in one among his many 199 EMINENT CHEMISTS OF OUR TIME addresses which never failed to interest, Remsen re- called this period: "While reading a text-book of chemistry I came upon the statement, * nitric acid acts upon copper.' I was getting tired of reading such absurd stuff and I determined to see what this meant. Copper was more or less familiar tome, for copper cents were then hi use. I had seen a bottle marked * nitric acid ' on a table hi the doctor's office where I was then 'doing tune!' I did not know its peculiarities, but I was getting on and likely to learn. The spirit of adventure was upon me. " Having nitric acid and copper, I had only to learn what the words 'acts upon' meant. Then the state- ment, 'nitric acid acts upon copper' would be some- thing more than mere words. All was still. In the interest of knowledge I was even willing to sacrifice one of the few copper cents then in my possession. " I put one of them on the table; opened the bottle marked 'nitric acid'; poured some of the liquid on the copper; and prepared to take an observation. But what was this wonderful thing I beheld? The cent was already changed, and it was no small change either. A greenish blue liquid foamed and fumed over the cent and over the table. The air hi the neighborhood of the performance became colored dark red. A great colored cloud arose. This was disagreeable and suffocating. How should I stop this? " I tried to get rid of the objectionable mess by picking it up and throwing it out of the window, which I had meanwhile opened. I learnt another fact nitric acid not only acts upon copper but it acts upon fingers. The pain led to another unpremeditated experiment. I drew my fingers across my trousers and another fact was discovered. Nitric acid acts upon trousers. 200 IRA REMSEN " Taking everything into consideration, that was the most impressive experiment, and, relatively, probably the most costly I have ever performed. I tell of it even now with interest. It was a revelation to me. It re- sulted in a desire on my part to learn more about that remarkable kind of action. Plainly the only way to learn about it was to see its results, to experiment, to work in a laboratory." The boy tasted experiment, and he liked it well; he tasted it again, and he liked it better. Plainly, chem- istry had something to it provided you could handle things and see things. Without any instruction beyond what he could get from the text-book and his own independent investi- gations, Remsen was next asked to act as lecture- assistant to the professor who had so well undertaken to develop the young man's chemical knowledge. Remsen was required to prepare experiments which he himself had never performed, and had never seen; the results can be imagined. He was further requested to form a " quiz " class in chemistry a request asking " the blind man to lead the blind." Success again was unavoidable, was it not? Here we get our first glimpse of science teaching in America in the sixties. Only by comparing its status then with what it is now can we form an opinion of the enormous change that sixty years have wrought. Remsen was pretty well disgusted with the teacher, but not with chemistry. But chemistry could not yet be taken up. His father said that he was to be a phy- sician, and a physician he had to be ; but if a medical man, he was at least going to some college with a better reputation. The father mildly protested, and so did the professor, but nevertheless Remsen entered his 15 201 EMINENT CHEMISTS OF OUR TIME name as a student of the College of Physicians and Surgeons of Columbia University. In 1867, at the age of 21, Remsen graduated as doctor of medicine. For a thesis, which was required of every member of the graduating class, he selected a subject dealing with the fatty degeneration of the liver. Ad- dressing the Medical Faculty of Maryland in 1878, Remsen referred to this thesis as follows : " Eleven years ago, in company with 99 others, I was proclaimed fit to enter upon the career of a medical man. My erudition in medical matters was exhibited in a thesis on the Fatty Degeneration of the Liver, a sub- ject on which I was and am profoundly ignorant. I had in fact never seen a liver which had undergone fatty degeneration, nor a patient who possessed, or was sup- posed to possess one; nor, I may add have I had that pleasure up to this day." And yet Remsen got one of the two prizes offered for the best theses! The College of Physicians and Sur- geons, since grown into the well-known " P. and S." school, was then perhaps a little better than the worst of its type, but very, very far from acceptable. There were no acceptable medical colleges in the United States. Johns Hopkins had not yet shown the way. What was Remsen to do now? True, his precepter, the "professor," offered him a partnership in his lucrative practise; but aside from any repugnance in going forth to kill when he could do that but clumsily, he really did not like medicine at all. The little experiment with copper and nitric acid still lingered in his mind. But if a chemist, where was he to go to get his in- struction? The big chemical laboratories at Harvard, at Chicago, at California, at Illinois, at Columbia, familiar to the student of to-day, were yet to be born. Harvard was a possibility, but small in comparison with 202 IRA REMSEN research centers on the continent. Remsen had read Liebig's Chemical Letters. Liebig was the great chemist of Germany, with but one rival, Wohler. Every- body spoke of Liebig; even the child in the street had heard of Liebig's beef extract. We are not told how well Remsen's father received the young man's proposed change of program. Whether well or otherwise, the younger man triumphed. Towards the end of the summer in 1867 the M.D. set out for Munich. Arriving in Munich, Remsen had his first hopes dashed to the ground by being told that Liebig no longer received students. All he did at this time was to give a lecture course in inorganic chemistry. The young foreigner then was forced to turn to the most promising privat- docent in Liebig' s laboratory, who happened to be Jacob Volhard. In Volhard's laboratory Remsen re- ceived his first systematic instruction in chemistry. Up to that time he had never made the simplest analysis ; he had only performed the crudest experiments for lecture purposes. He spent two semesters in Munich, from October 1867 to August 1868, working in Volhard's laboratory. The privat-docent had few students sometimes Rem- sen was the only one in the laboratory. This was an extremely fortunate circumstance for the American; he received private instructions from one of the best laboratory manipulators of the day. Remsen also attended Liebig's course of lectures. At the end of the year Volhard advised him to go to a larger laboratory and suggested Gottingen. Fortunately, Wohler, the professor at Gottingen, was then in Munich, on a visit to his old friend Liebig. Through Volhard Remsen secured an introduction to Wohler, who told hmi that he would be very welcome in Gottingen. 203 EMINENT CHEMISTS OF OUR TIME Wohler kept his promise; he even procured a nice lodging for the young man. Remsen came to work directly under Fittig, then pro- fessor extraordinarius at Gottingen. In due time the undergraduate became a research worker, with the oxidation of xylene (a compound closely allied to ben- zene) as a subject to work upon. The outcome of this research was sufficiently promising to warrant Fittig suggesting another line of work, this time connected with a method of synthesis which Fittig had inaugurated, and which still bears his name. This was not so suc- cessful. To complete his requirements for the Ph.D., Remsen undertook another investigation, one dealing with piperic acid. The results of this work were embodied in his dissertation presented to the faculty of the uni- versity in partial fulfilment of the requirements for the degree of doctor of philosophy, and later published in the Annalen der Chemie. Early in 1870 he received the doctor's degree. Remsen was about to return home when Fittig re- ceived a call to Tubingen to succeed Strecker, where- upon Fittig suggested that Remsen should accompany him to Tubingen as an assistant. To this Remsen gladly assented. In Tubingen he remained for two years, acting as lecturer and laboratory assistant, and utilized his spare time in carrying on investigations of his own. In Tubingen, also, Remsen made the acquaintance of William Ramsay, then a young undergraduate but recently arrived from England under somewhat dra- matic circumstances. " Ramsay appeared in the labor- atory for the first time. Ringing for a long time at the door he was finally answered by a young man in overalls. ' Konnen sie mir sagen wo ist die Vorlesungszimmer? ' 204 IRA REMSEN queried Ramsay. This was shocking German, but he had done the best he could with his phrase book." The " young man in overalls," who was none other than Remsen, looked at the stranger, paused, and then said, " Oh! I guess you want the lecture-room! H Remsen and Ramsay became great chums. Around them they gathered most of the English, Scotch and American students in Gottingen. A baseball club was formed, in which the English (including the present Lord Milner ) and Scotch took part, but not the Germans. Then there was skating on the ice winter afternoons, and sometimes dinner parties in the evening, when Ramsay entertained the company with " A fine Old English Gentleman," to his own accompaniment. In 1872 Remsen returned to the United States after having spent nearly five years in Germany. He was now a university man, appreciated university life, and could conduct research. But what opening was there for such a man? He wandered to Philadelphia, and there completed a translation of Wohler's Organische Chemie which he had begun in Tubingen, and which H. C. Lea and Company had promised to publish. But what next? At times he lost faith and became despondent. He had given up one profession, prepared himself for the practise of another, and apparently every position was filled and every opportunity had been seized by some- one else. His long absence from the country and his change of pursuit had left him with practically no one to look to for help and advise. After some months of fruitless endeavour to get some- thing, he received an offer from the University of Georgia, and close upon this offer came another, from Williams College. Offers, like sorrows, come not in single file, but in battalions. 205 EMINENT CHEMISTS OF OUR TIME Remsen accepted the appointment at Williams College as professor of physics and chemistry. When he got there he found the cupboard bare Williams College possessed no laboratory! A mild request for one received the following answer from the president: " You will please keep in mind that this is a college and not a technical school. The students who come here are not to be trained as chemists or geologists or physicists. They are to be taught the great fundamental truths of all sciences. The object aimed at is culture, not practical knowledge." With which immortal dis- course the great man dismissed the subject. At the end of a year, the board of trustees did, however, build Remsen a small laboratory for his own use, and here, amid such discouragement, he prosecuted research on the action of ozone on carbon monoxide, on phosphorus trichloride, and on derivatives of benzoic acid. The results were published in the American Journal of Science and in the Berichte der deutschen chemischen Gesellschaft. " I remember," writes Remsen, " that once after the appearance of one of my articles in the American Journal of Science, we had a faculty meeting in the college library. Someone picked up the number of the journal containing my article, and some good-natured fun was poked at me when an attempt was made to read the title aloud. I felt that in the eyes of my col- leagues I was rather a ridiculous subject." Remsen was only 27 then, and over-sensitive. So four years were passed. In the meantime, a book on Theoretical Chemistry, which Remsen had written during his many despondent hours, proved an extra- ordinary success. The novel method of presentation, the systematic arrangement, a rare clearness and sim- plicity in style, afforded it a welcome among all scientific 206 IRA REMSEN workers. It passed through five editions, and was trans- lated into German and Russian. Later, when at Johns Hopkins, Remsen wrote a number of books on inorganic and organic chemistry, with almost unvarying success. Had his reputation to rest on nothing more than author of such text-books, he would find no inconspicuous place in the history of chemistry in America. Then in 1876 came that great change in universities in the United States with the establishment of a graduate school at Johns Hopkins, in Baltimore. Huxley, then in this country, very appropriately ushered hi the new era by an address of welcome. Gildersleeve, the Greek scholar, Rowland, the physicist, and Sylvester, the mathematician, were appointed to form a nucleus of promising scholars. To this trio was added Ira Remsen as professor of chemistry. He was then thirty years old. The position could not have been more ideal. Em- phasis was to be placed upon advanced, graduate work, the professors were expected to do research, and the necessary facilities were to be provided to the extent that money could provide them. There were no petty restrictions of any kind. " Do your best work and do it in your own way." That was the only advice Presi- dent Gilman had to offer. In May, 1877, Remsen delivered his first lecture on advanced organic chemistry to a small group of students huddled together in a room which has since become a storeroom for odds and ends. Research was begun immediately. Regular weekly meetings to discuss current topics were also introduced. "... nowhere else [in America], so far as I know, had the advanced students been taken in and given an opportunity to acquire the habit of familiarizing themselves with the current progress of the science and of perfecting them 207 EMINENT CHEMISTS OF OUR TIME selves in the art of giving concise and lucid expression to the information acquired in the course of their reading." 1 The extensive series of researches begun in 1877 and carried on without a break well into the twentieth century dealt with various phases of organic chemistry. Perhaps the most interesting outcome from a practical stand- point was the preparation of orthobenzoic sulphinide, or saccharin^ in 1879. This substance, obtained from toluene, a product of coal tar, is unique in being five hundred times as sweet as sugar. In spite of the more than 100,000 carbon compounds that have been pre- pared, no substance similar to it in sweetness has ever been unearthed. And the wonder increases when we remember that, chemically, saccharin and sugar have nothing in common. At first Remsen sent his contributions to Prof. J. D. Dana for the American Journal of Science, but soon the amount of matter grew to such proportions, that it fright- ened poor Dana. The work was of such a specialised character; perhaps it would be more desirable to send such contributions to foreign journals? queried Dana. Remsen felt that the time had come to found a chemi- cal journal in America. With this in view, he got into touch with the leaders of science. Most of them dis- couraged the plan; very few had anything to say in favor of it. Despite this cold reception, he started the American Chemical Journal in 1879. It proved a suc- cess from the start. Workers from all over the country began to flood the publication with contributions. As a stimulant to research in chemistry at various scientific centers, the Journal stood in the same relation as John 1 Prof. H. N. Morse, Director of the Johns Hopkins Dept. of Chemistry. 208 IRA REMSEN Hopkins University did towards the other universities of the country. For many years, and long after influential scientific centers had sprung up in the United States, the American Chemical Journal continued to be the sole medium for the publication of American chemical research. In the beginning of the twentieth century the Journal of the American Chemical Society, the official organ of the American Chemical Society, came to the forefront, and in 1914, Remsen's journal, its purpose served, was dis- continued. In the last number of the American Chemical Journal Remsen says: "The American Chemical Society has grown to great importance and is amply prepared to provide for the publication of all articles on chemical subjects likely to be prepared in this country. . . . Taking everything into consideration it now seems best to the editor to place the control of his journal in the hands of the society. It is needless for him to say that after 35 years of editorial work he does not now withdraw from it without a feeling of deep regret. His earnest hope is that the step may prove wise." During the absence of President Oilman in Europe in 1889-90 Remsen served as acting president of Johns Hopkins, and in 1901, when President Oilman retired from office, he was elected as Oilman's successor. This office he held with marked distinction until 1912, when he resigned. During his tenure of the presidency what distinguished it particularly was the perfect freedom he allowed pro- fessors. He realized that " every man does his best work when he is allowed to do it in his own way." " The many criticisms that in recent times have been directed toward this [the president's] office in our American institutions are certainly not applicable to him. 209 EMINENT CHEMISTS OF OUR TIME He never abused the power placed in his hands, there has been no autocratic interference with the autonomy of the individual departments, and above all there has been no suspicion of indirection in his dealings with his staff. We have had implicit confidence in his motives. . . . We have been very contented, happy, and prosper- ous under his administration." 1 It has been pointed out how, first as writer, then as investigator, and finally as editor, Remsen's influence upon chemical research in America has been profound; as teacher, it was no less so. " I will only say, as many others have said before me in effect, that I have never seen his equal as a master of simple and lucid exposition ... as a teacher of many other teachers, his influence, direct and remote, has been and will continue to be of incalculable value to American students of chemistry." 2 His former students are some of our very best chem- ists to-day: Orndorff of Cornell; (the late) H. C. Jones of Johns Hopkins; W. A. Noyes, Illinois; Kohler, Har- vard; C. H. Herty, editor of the Journal of Industrial and Engineering Chemistry; J. F. Norris, Mass. Inst. of Technology; S. R. McKee, Columbia; E. E. Reed, of Johns Hopkins; and Burton and Gray, superintendent and chief chemist respectively of the chemical depart- ment of the Standard Oil Company. Several attempts to induce Remsen to leave Baltimore for other and more lucrative positions, proved futile. The University of Chicago made a particularly tempting offer, but Remsen remained true to Johns Hopkins. " This is my birth for life," he said in an address to the students. When Remsen went to Williams as a very young man the students " had it in for him," so some of them con- 1 W. H. Howell, prof, of physiology at Johns Hopkins. 2 Prof. H. N. Morse. 210 IRA REMSEN fessed quite frankly later. With time the students' desire to make it " hot " for the teacher gave place to a desire to please. Rernsen with his simplicity, his humor, his interesting methods of presenting the subject, made himself very much liked. At Johns Hopkins he was extremely popular because, in addition to sound scholarship, he had so much of the milk of human kindness; he forgave much. One point, however, about which he was very particular was punctuality. A story is told of him in this respect. While engaged in a lecture upon some of the chemical elements, he was in the act of describing some attributes of sulphur. As he uttered the first syllable, " sul ," the door in the back of the room opened and a young man noted for his habitual lateness entered. The in- structor stopped short and stood with the word half uttered while the abashed student, in the midst of an awful and soul-oppressing silence, made his hasty way to a seat. Then with a tone of strong relief, and with the interest of each student intensified upon him, Remsen suddenly gave expression to the concluding syllable of his word " phur! " At the request of the National Board of Health of Baltimore, Remsen, in 1881, undertook an investigation into the organic matter in the air, and a study of the impurities in the air of rooms heated by hot air furances and by stoves. Similar work was done for the city of Boston. In 1882 he became a member of the National Academy of Sciences, and in 1884 served on a com- mittee appointed to investigate the glucose industry of the United States. Another committee upon which he served dealt with the question of the processes employed in denaturing alcohol. In 1909 President Roosevelt appointed Remsen chair- man of a board of consulting scientific experts to aid 211 EMINENT CHEMISTS OF OUR TIME the Secretary of Agriculture in matters pertaining to the administration of the pure food law. The other members of this board were Dr. R. H. Chittendon, Director of the Sheffield Scientific School; Dr. J. H. Long, Professor of Chemistry and Director of the Chem- ical Laboratories in Northwestern University; Dr. C. A. Herter, Professor of Pharmacology and Therapeutics, Columbia University; Dr. A. E. Taylor, Professor of Pathology and head of the Department, University of California; now Professor of Physiological Chemistry in the University of Pennsylvania. Dr. Herter died in De- cember, 1910, and Dr. Theobald Smith, Professor of Comparative Pathology in the Harvard Medical School, was appointed to fill his place. The Board was gener- ally known as the " Remsen Board." Dr. Wiley, chief chemist of the U. S. Department of Agriculture, selected a number of men as subjects for investigation on the assimilation of benzoate of soda. These men came to be known as the " poison squad." Dr. Wiley declared that in experiments which had lasted some twenty days, a number of the men had become ill. The maximum amount of the sodium benzoate given to any one man, and distributed over the twenty days was one and two-thirds ounces. Dr. Wiley's conclusion did not pass unchallenged. Some authorities declared that the fever of the young men was due to nothing more than an epidemic of grip which was then raging. Neither were the experiments themselves considered very satisfactory. The majority of the individuals had been used in previous experiments where they had been made ill ; and the sodium benzoate, instead of being distributed in the food just as it is when used as a preservative was given to the patients in capsules. 212 IRA REMSEN The members of the " Remsen Board " repeated Wiley's experiments, working quite independently of one another. The assistants took from one-third of a gram to six grams (1/5 oz.) daily, and in no instance were any ill-effects noticed. Now the law allowed no more than 0.3 gram of sodium benzoate for one pound of beef, which was only one-twentieth of what the assistants had received. In 1914 the " Remsen Board " reported on the use of alum in baking powders; this they found to be non- injurious, provided too large quantities were not used. Large amounts provoke catharsis, due to the sodium sulphate which results from the reaction. The general conclusion drawn was that alum baking powder was no more harmful than any other baking powder ; but possi- ble secondary effects due to chemical reactions between the ingredients made it seem advisable to recommend that food leavened with alum baking powder should be used in moderate quantities only. Remsen has been the recipient of many honors. The LL.D. was conferred upon him by Columbia in 1893; Princeton, 1896; Yale, 1901; Toronto, 1902; Harvard, 1909; and Pennsylvania, 1910. In 1898 he was elected a Foreign Fellow of the London Chemical Society, and in 1911, a Foreign Member of the French Chemical Society. In 1902 he was elected to the presidency of the American Chemical Society, and in the following year to that of the American Association for the Advance- ment of Science. From 1907-1913 Remsen was President of the National Academy of Sciences the highest American scientific distinction. The president preceding Remsen had been Alexander Agassiz. In 1908 he was awarded the Gold Medal of the Society of Chemical Industry (England), and two years later became its president. In 1914 he 213 EMINENT CHEMISTS OF OUR TIME received the Willard Gibbs Medal of the Chicago Section of the American Chemical Society. Remsen was married in 1875 to Elizabeth H. Mallory, a daughter of a New York merchant, who with his family spent his summers in Williamstown. They have two sons, Ira M. who is an artist, and Charles M., a surgeon, practicing in Atlanta, Ga. As President of Johns Hopkins, Remsen's time for research was very limited. One of his reasons for retiring from the presidency was a desire to return to the love of his younger days, and this " return to the fold " made him happy again. " The transformation from university president to chemist is complete, and I rejoice." References Part of the information comes from private sources. Remsen's address before the Chicago section of the American Chemical Society, delivered in 1914 (i) contains much of biographical interest. For details regarding the Tubingen days, Tilden's Sir William Ramsay (2) has been of service. Other articles that were found useful were 3, 4, 5, 6, 7 and 8. Remsen's celebrated article on saccharin was pub- lished in the American Chemical Journal (9). He is also the author of a number of well-known texts, refer- ences to some of these being given (10, u, 12, 13, 14). 1. Ira Remsen: The Development of Chemical Research in America. Journal of the American Chemical Society, 37, i (1915)- 2. Sir W. A. Tilden: Sir William Ramsay (Macmillan and Co. 1918). 3. Anon.: Referee Board Reports on Alum Foods. American Food Journal, May, 1914, p. 188. 4. Anon. : A Vindication of Benzoate of Soda from the attacks of Dr. Wiley. Current Literature, 52, 304 (1912). 214 IRA REMSEN 5. Marcus Benjamin: Prof. Ira Remsen, President of the Ameri- can Association for the Advancement of Science. Scientific American, 88, ig (1903). 6. Anon.: Johns Hopkins' New President. Baltimore Sunday Herald, Oct. 13, 1901. 7. Marcus Benjamin: Development of Chemistry in America. The Star, May 25, 1890. 8. Anon.: The Resignation of President Remsen. The Johns Hopkins University Circular, No. 10, 1912. 9. Ira Remsen and C. Fahlberg: On the Oxidation of Substitution Products of Aromatic Hydrocarbons. IV. On the Oxidation of Orthotoluenesulphamide. American Chemical Journal, 1, 426 (1879). 10. Ira Remsen: Principles of Theoretical Chemistry (H. C. Lea's Son and Co., Philadelphia. 1883). 11. Ira Remsen: An Introduction to the Study of the Compounds of Carbon (D. C. Heath and Co., Boston. 1906). 12. Ira Remsen: Elements of Chemistry (Macmillan and Co. 1887). 13. Ira Remsen: Inorganic Chemistry (Macmillan and Co. 1889). 14. Ira Remsen: A College Text-Book of Chemistry (Macmillan and Co. 1908). 215 EMIL FISCHER news has reached us that Emil Fischer no more. Since the fateful August, 1914, Germany has lost her Ehrlich, her Buchner and her Baeyer; England, her Ramsay, Crookes and Moseley. Deaths occur, wars or no wars ; yet Buchner might have lived had not a shell cut short his existence ; and young Moseley had barely started along his brilliant career when he, like the promising Rupert Brooke, laid down his life for his beloved England. Ramsay's end, we know, was hastened by manifold war duties. To what extent Fischer was a victim of the war is still unknown to us; but we were told, from time to time, of his violent pan- Germanism, doubtless encouraged by the exalted posi- tion he held under the crown. The magnitude of Germany's debacle would have crushed a spirit less proud than Geheimer-Regierungsrat Fischer. Whatever opinions we may have regarding Fischer's political affiliations, there can be no question of his position in the history of chemistry. His bitterest enemies are the first to pay tribute. He easily takes his place as the greatest organic chemist of our generation. To appreciate his work a little more, we must look into the state of the science when Fischer began his labors. In those days in the seventies organic chem- istry, or the chemistry of the compounds of carbon, was a field for the most fruitful research. The addition of carbon and hydrogen and oxygen atoms, and the vari- ous rearrangements within a molecule, could be accom- plished with such relative ease, that candidates wishing 16 217 EMINENT CHEMISTS OF OUR TIME to get a doctor's degree in the shortest time were readily attracted to this branch of the science. New compounds of carbon were being daily manufactured by the score in Germany, England and France. In many cases these compounds have remained of interest to the writers of reference books only. A number, however, found wider application in the dye and drug industry. That animal and vegetable life were largely made up of carbon compounds, that the food we eat could be largely divided into fat, proteins and carbohydrates, all this was known. If, then, a knowledge of the composition of these substances, as truly belonging to organic chemistry as marsh gas or benzene, was vague and wholly unsatisfactory, this was due to the complexity of their make-up. Chevreul and Berthollet had cleared the situation in so far as the fats were con- cerned, but the chemistry of the carbohydrates, and particularly that of the proteins, remained as mysterious as ever. The three foodstuffs were the borderland where chemistry ended and biology began; the lack of a solution of the composition of at least two of these foodstuffs left the finishing touches of the edifice of organic chemistry still undone, and gave a wholly un- satisfactory foundation for the science of physiology. To the solution of this problem Fischer pledged his life while still a student, and brilliantly did he fulfil his life's task. With an imagination tempered only by a splendid scientific training, an originality of mind which made a lasting impress upon every piece of work with which he was associated, and a rare skill in devising apparatus, he, first by his own labors, and later, as director-general of an army of aspiring students, gradu- ally unfolded the mysteries that had enshrined the most complex chemical substances known to man. Like all 218 EMIL FISCHER great contributions, his has added not only to our chemi- cal knowledge, but has shed a flood of light on cognate sciences, such as botany, zoology and physiology. Fischer was born in Euskirchen, Rhenish Prussia, on October 9, 1852. His father, Lorenz Fischer, was a successful merchant whose success in business must have made a deep impression upon his son, for Emil, after matriculating the gymnasium in Bonn, joined his father's concern at the age of seventeen. This enthusiasm for the commercial world, however, was short lived. Within two years he had abandoned all thoughts of high finance, and has inscribed himself as a student at Bonn University. Kukule, one of van't Hoff's teachers, was the professor of chemistry, and Engelbach and Zincke were his active assistants. Fischer came in contact with all three. The ill-omened Franco-German war had barely termi- nated when the German government decided to found a university at Strassburg. To this place, in the autumn of 1817, Fischer, true to the German student's traditions, came to spend part of his wanderjahre. The initial training for a chemist required a sound course in in- organic chemistry, particularly of an analytical kind. Under Rose, Fischer was made acquainted with Bunsen's methods for the analysis of water, an experience which was of use when the young man undertook to do analyti- cal work for the town of Colmar. By the end of a year Fischer was ready for the next step in the training of a chemist a course in organic chemistry. This brought him in contact with Adolf von Baeyer, the professor of the subject. Baeyer, a man of eighty, died recently in Munich. He was the connecting link between Liebig and Wohler on the one hand, and his own pupils who so brilliantly carried on the best traditions of the great school of 219 EMINENT CHEMISTS OF OUR TIME organic chemistry which Liebig and Wohler had built. To him, even when at the small Gewerbeakademie in Berlin, came Graebe and Liebermann, whose synthesis of alizarin has already been discussed (see Perkin); and Victor Meyer, the conquering hero among chemists. Fischer now came to pay homage. At a later date Will- statter joined the little band of Baeyer's scholars. Fischer and Baeyer are no more, but Willstatter, the chlorophyll wizard, who has recently been appointed to Baeyer's chair in Munich, bids fair to equal, if not out- strip his master in quality and originality of work. Fischer immediately came under the spell of Baeyer. The professor was rapidly reaching the height of his intellectual output. His amazing mastery of every phase of the subject, the keen criticism to which every piece of work was subjected, the fertility of his ideas, combined with the fatherly care he took of his " child- ren," the students, made Baeyer very popular with his assistants and research workers, not least of all with Fischer. In July, 1874, Fischer completed an investigation on the coloring matters fluorescein and orcin-phthalein, for which he received his Ph.D. His immediate appoint- ment to an assistantship was evidence that he had already made an impression upon Baeyer, whose faculty for detecting promising material was not the least of his gifts. In less than a year Fischer, with his discovery of phenylhydrazine, forged to the very front rank of organic chemists. Later this substance in his hands proved the most effective tool in synthesising the sugars, which are typical members of the carbohydrate family. To-day the osazone test for sugars, a test depending upon the use of this same phenylhydrazine, is among the commonest and the most effective methods used by 220 EMIL FISCHER the chemist, the physiologist and the clinician for the isolation and detection of the sugars. Little wonder, then, that when Baeyer in this same year was selected to succeed Liebig in Munich, he was desir- ous that young Fischer should accompany him. This, of course, was just what Fischer wanted. For the next three years Fischer held no official posi- tion at the University of Munich. As events proved, this was the most fortunate thing that could have happened. He had no students to instruct, no labor- atory work to supervise; the entire time could be de- voted to research. And how well did Fischer make use of this time! With phenylhydrazine as the starting point, the various derivatives of this parent substance were investigated, and its relationship to a group of substances that act as " intermediates " in the manufacture of dyes the diazo compounds, was clearly established. The ease with which phenylhydrazine combines with other sub- stances gave rise to an almost endless series of new compounds. To us of particular interest is its combina- tion with two important classes of organic compounds known as the aldehydes and he tones a discovery which found direct application in the chemistry of the sugars. Victor Meyer, by the use of hydroxylamine, a substance closely related to ammonia, had also shown how the aldehydes and ketones could be recognized. Starting from two different angles, Meyer and Fischer, who became the closest of friends, and whom Baeyer regarded as his two most talented pupils, met on com- mon ground. Between them they opened up two vast chapters hi organic chemistry. At the same time, Fischer, in collaboration with his cousin Otto Fischer, began an investigation of the rosaniline dyestuffs the magenta of Perkin which 221 EMINENT CHEMISTS OF OUR TIME terminated in the brilliant discovery that these dyes were all derivatives of a base triphenylme thane. The importance of this work may be gauged when we reflect that Otto Fischer owed his appointment as pro- fessor at Erlangen to this investigation, and its possi- bilities are such that all of Otto Fischer's subsequent contributions have largely centered around the pioneer work in which his cousin played such a leading part. Genius will out, and recognition came quickly. Fisch- er was made privat-docent in 1878, and at the end of the year was promoted to the extraordinary professorship and given entire charge of the analytical department in Baeyer's laboratory. Then began those classical investigations into the active constituents of coffee and tea, caffeine and theobromine, and their relationship to xanthine and guanine decomposition products obtained from the protein in the nucleus of cells which ultimately opened up an entirely new chapter in plant and animal chemistry. In the Easter of 1882 Fischer accepted a call as full professor (ordinarius) to Erlangen, and three years later he exchanged this chair for one in Wurzburg. Fischer was not much over thirty when he assumed charge in Wurzburg, yet the ten years which had passed since he had received the doctor's degree had been put to such good use that he already belonged to the four or five leading chemists of Germany. Thus far his work had been carried out with little assistance, but now, as an ordinarius, research students were not wanting, particularly in view of Fischer's eminence. Under his supervision a fine new laboratory was built, and with his active co-operation his students continued work on indol, uric acid and the sugars. After many weary trials, Fischer managed to syn- thesise the most important sugars among them fruit 222 EMIL FISCHER and grape sugar and also to prepare many new ones artificially. It was in the course of this intricate and laborious work that he had occasion to put van't Hoff and Le Bel's theory of the asymmetric carbon atom to exhaustive tests, with results which established the theory more firmly than ever. This work on the sugars threw some light on the method by which carbohydrates are formed in the plant. We know that the carbon dioxide and the moisture are taken up from the air by the plant and, in the presence of chlorophyll, are first probably converted to glucose, then to starch and fat and, in the presence of nitrogen obtained from the soil, partly to protein. Baeyer's theory of the first part of the reaction is that the carbon dioxide and moisture combine to form formalde- hyde (" formalin "), liberating oxygen, and that by poly- merization, or a method of coalescing, the formaldehyde molecules condense to form a molecule of sugar. This theory received its first experimental support when Butler off showed that formaldehyde in the presence of lime water yielded a sugar-like mixture. It was left, however, for Fischer to prove that this sugar-like mixture contained a small quantity of a substance, a-acrose, which he was able to transform into glucose. Fenton completed the cycle by his success in converting carbon dioxide into formaldehyde at a low temperature. Thus the initial chemical processs in the plant were in 1 a measure duplicated in the chemist's laboratory. Even the conditions of normal temperature under which these reactions proceed in the plant were fulfilled. But the well-nigh 100 per cent efficiency of the plant could not be even distantly approached. The mechanism of the reverse process, by which such a substance as glucose is oxidised in the body to carbon dioxide and water, is hardly better known. We do 223 N: EMINENT CHEMISTS OF OUR TIME know that oxidising ferments facilitate the reaction at body temperature, and the work of Dakin and Lusk in this country has made it seem probable that a glycerin- like substance or substances, and lactic acid, are im- portant intermediate products. Thus, as in simpler chemical reactions, the beginning and end of the reaction are clear, but again like any chemical reaction, the intermediate steps are very difficult to elucidate. It was in the course of these epoch-making experi- ments on the sugars, when phenylhydrazine was con- stantly used, that Fischer began to suffer with chronic poisoning, due to the inhalation of the vapors of this substance. Its effects he never got rid of, and from then on he was more or less of a semi-invalid. This might perhaps explain why in after years students found him somewhat of a " grouch " and quite unapproachable. The testimony of some of his students at Wiirzburg seems to bear conclusive witness to the fact that in those days, at least, he was not only an inspiring leader and lecturer, but took a very active interest in his re- search men. It was no uncommon thing to see him spend a couple of hours at the desk of one of his students, not only discussing the problem and offering suggestions, but actually illustrating experimental methods of pro- cedure. Such illustrations were simply priceless in value to the young kandidat, for Fischer was a master manipulator as well as a master thinker. '" Like Victor Meyer and Ramsay and van't Hoff, the appointment to a full professorship made feasible his marriage to the lady he had long courted, Fraulein Agnes Gerlach. The two made a striking pair. Both were tall and handsome, with intellect and wit a-plenty. Their son, Hermann, has faithfully followed in his father's footsteps. 224 EMIL FISCHER In 1892 came the crowning event of his career. A. W. mann, who had been professor at the Royal School emistry in London for some years, and had there taught such men as Crookes and Perkin, and had then been appointed to the chair of chemistry at Berlin Uni- versity, died, amLFischer was selected to succeed him. This was a sig^fcionor, for the Prussian Ministry of Education left i^^sfene unturned to make Berlin the foremost center of learning and research in the Empire, and only men whose standing in the world of scholarship was universally conceded, were at all considered. Fischer^tipulated that he would accept the position nly on c^dition that a new laboratory would be built r him. He had in mind his splendidly-equipped labor- atory in Wurzburg, where the authorities provided him with ample facilities and gave him unrestricted freedom to equft) the chemistry building with the best and the latest ^novations. The Berlin authorities promised the new laboratory, and so Fischer moved to his new home. Fojy years, however, were to pass before the foundation- for the new structure was to be laid. This was the bad financial condition of the university. Berlin Fischer continued his work on the sugars, fact that many of these bring about fermentation Fischer to fruitful studies on the possible consti- ferments and their relationship to the substance n. This subject of ferments, or enzymes, is (Ben tremendous significance in the activity of all life-]!Pb*cesses, that it merits a somewhat detailed discussion. The word^izyme comes from a Greek word meaning " in yeas^' w > erhaps the most acceptable definition in flight of recent scientific research is to say that it is a stance showing the properties of a catalyst and pro- ed as a result of cellular activity. EMINENT CHEMISTS OF OUR TIME But what is a catalyst? The reader may recall his first very simple experiment in the preparation of oxy Here the instructor tells the bewildered youth you put a little potassium chlorate in a test tube and heat this very strongly, a gas is evolved which can be identi- fied as oxygen. Now by merely addin^a small quantity of a dirty black-looking powdej, caMfcmanganese di- oxide, to the potassium chlorate, the^Qrgen is evolved much more rapidly and at a much lower temperature. But this is not all. A careful examination at the end of the reaction shows that the manganese dioxide has not changed in any way: we have the same substonce, and the same amount, at the end of the reactioIRs at th< beginning. Many such substances are known to chem ists. They all have this peculiarity: that they accel- erate chemical reactions, 1 and that a relatively small, at times insignificant quantity of the substance suffices to bring about the chemical change. In cells we find substances of this type, but thus far these cellular " catalysts," unlike the manganese di and like proteins, have never been produced outsi the cell. When we consider that life is possible only because continued cellular activity, and when we bear in that this activity is largely the result of chemical ch brought about by these enzymes, the param portance of these substances becomes manifest. Alcoholic fermentation with yeast, the so milk, processes of putrefaction, and various other^ ex- amples of changes in organic materials with, often enough, the accompanying liberation of bibles of gas, had long been known. The epoch-makii^ researches^ of Pasteur had shown that fermentations and putr^ factions were inaugurated by the presence of lii 1 Cases are known where they retard chemical reactions. 226 EMIL FISCHER organisms. Then extracts from the saliva and the gastric mucosa of the stomach were obtained which also had the power of bringing about chemical changes in carbohydrates and proteins. This led to the classi- fication of ferments into those which, like yeast and certain bacteria, acted because of certain vital processes (organised ferments), and those which, like the extracts from the saliva and stomach, were presumably " non- living unorganized substances of a chemical nature " (unorganised ferments) Kiihne designated the latter enzymes. This classification was generally accepted, and the " vitalists " held absolute sway until 1897, when Emil Buchner, fired by Fischer's work, overthrew the whole theory by a series of researches which, in their influence, were only second in importance to those of Pasteur in an earlier generation. One of Buchner's classical experiments consisted in grinding yeast cells with sand and infusorial earth, and then subjecting the finely pulverized material to a pressure of 300 atmospheres a pressure far more than enough to destroy yeast, or any other cells. The liquid so obtained had all the fermentative properties of the living yeast cell. Obviously, then, the living cell could not be responsible for the fermentation. On the other hand, this experiment did suggest that cellular activity gave rise to some substance which, once produced, exerts its influence whether the cell is alive or dead. All subsequent experiments have but strengthened the con- viction that cells do produce these substances, and that the chemical changes are due not to the living organ- isms, but to the lifeless substances (enzymes) to which the se organisms give rise. Minute in quantity, and tenaciously adhering to sub- stances present, particularly protein, the isolation of an enzyme in the pure state has become one of the most 227 EMINENT CHEMISTS OF OUR TIME difficult problems in physiological chemistry. Yet any elementary student in the subject finds little difficulty in performing simple experiments which convince him either of the presence or the absence of the enzyme. The method consists essentially in making use of the so-called " specificity " of enzymes, a conception for which Fischer is largely responsible. Fischer's synthetic work in the sugar series, particu- larly his studies into the configuration of cane sugar, maltose and lactose, received a great impetus from the success which attended his efforts in preparing gluco- sides combinations of glucose and one or more other substances artificially. By the study of emulsin, and other enzymes in yeast, on such glucosides, Fischer found that the slightest change in the configuration of the glucoside inhibited the action of the enzyme. Zy- mase, another enzyme in yeast, which is directly re- sponsible for the conversion of glucose into alcohol, behaved similarly. This led him to the conclusion that a close chemical relationship exists between the enzyme and the substance on which it acts a view which led to his famous analogy of the lock and key relationship. Just as one key fits one lock, so any one enzyme will act on only a certain type of substance. Take, for example, the enzyme found in saliva, ptyalin; it readily acts on the carbohydrate, starch, but has no action on protein. Again take the pepsin of the stomach: this enzyme breaks down proteins, but is without result on carbohydrates. These instances may be multiplied indefinitely. Some enzymes show their specificity to an even more marked degree. Fischer's work has given us beautiful illustrations. Even in the yeast cell we find one, sucrase, which acts only on cane sugar (sucrose), but on no other sugar or any carbohydrate. 228 EMIL FISCHER In the winter of 1894 Fischer resumed his earlier work on uric acid and caffeine. After three years he suc- ceeded in synthetically producing every constituent of the group, and traced them all to a mother substance to which he gave the name of purin (a word suggested by the phrase purum uricurri). The chemist, the physiologist and the pathologist can but wonder at such genius. Here are the most complex and the most important class of protein bodies, the so-called nucleoproteins, which as their name implies, are found in the nucleus of the cell, and which, hi the course of their chemical decomposition in the body, give rise to xanthine, hypoxanthine, adanine, guanine, etc. all typical purines; here are these purines which, in their further travels in the body, come to the liver, where a large percentage of them are oxi- dised to uric acid another member of the purine family. This same uric acid is a never-failing constituent of the urine, and its quantity gives valuable data regarding nucleoprotein metabolism in the body, of paramount importance in such a disease as gout. The inter- relationship of these complex purines, as well as their relationship to plant analogues, such as caffeine and theobromine, have been as thoroughly probed by Fischer as the composition of water or that of air. He has gone even further. Having found relationships, and having traced the substances to one mother substance, he has succeeded in building them all up from this mother substance a piece of work which, with but one excep- tion, finds no equal in synthetic chemistry. The one exception is Fischer's crowning series of re- searches on the proteins. No work approaching this had ever been done before. The proteins are the most important of the three classes of foodstuffs. Without them cellular growth and 229 EMINENT CHEMISTS OF OUR TIME repair would be impossible. The belief has been general that the elucidation of their constitution would open up the key to some of life's great mysteries. Fischer was not the first to tackle this problem of problems, but he was the first to give the lead in the right direction. As a result of nearly a century's labor by many chem- ists and physiologists) the proteins have been shown to be made up of combinations of much simpler substances, the amino-acids, the first and simplest of which, glycine, was synthesised years ago by Perkin. The process by which these ammo-acids are obtained from proteins is known as hydrolysis, because water plays an indispens- able part in the reaction; and this hydrolysis can be brought about either by the use of acids, alkalies or such enzymes as pepsin and trypsin, which are found in the stomach and pancreas respectively. The changes that the protein undergoes in the stomach and the small intestine can be duplicated in the laboratory, and it is then shown that this hydrolysis proceeds in stages, giving us metaproteins, primary proteoses, secondary proteoses, peptones, polypeptids and amino acids all more or less well-defined substances, whose chemical complexity is greatest at the protein end, and simplest at the amino- acid end. The crude physical methods of classifying proteins have pointed to the fact that there are some 40 to 50 in number. All of these, when hydrolysed, give a large percentage of the 19 amino-acids which are common to most proteins; the differences among proteins is most marked in the amount of the various amino-acids which they yield when hydrolysed. Due in no small part to the labors of Fischer and his co-workers, most of these nineteen amino-acids have been synthesised from simpler bodies. 230 * EMIL FISCHER If the hydrolysis of proteins, and the investigation of the decomposition products so produced was a difficult task, what are we to say of the reverse process, whereby, by starting with amino-acids, we build up proteins? Yet that is what Fischer did. He succeeded in work- ing out methods by which amino-acids could be chemi- cally joined on to one another in some such way as the links of a chain. He has given the name polypeptids to such combinations of amino-acids. In his most celebrated experiment in the synthesis of proteins, Fischer succeeded in combining eighteen amino-acids an octadecapeptid which is one of the most complicated artificial substances that has ever been produced, and which shows some very striking resemblances to the natural proteins, not the least of which is the way trypsin, the pancreatic enzyme, breaks it up into the ammo-acids out of which the artificial protein was built. The enzymes, as the reader may remember, are specific in their reaction. The trypsin is an enzyme which acts only on proteins and on no other class of substances; hence its action on Fischer's octadeca- peptid is good evidence in support of the view that the artificial product is really of the nature of at least the simpler proteins. The starting materials for this synthesis cost $250; "so that," says Fischer, "it has not yet made its appearance on the dining table ! " These glorious researches were still in full blast in 1902 when Fischer was awarded the Nobel prize in Chemistry, the prizes in physics going to van't Hoff's countrymen, H. A. Lorentz and Pieter Zeeman; in medicine, to Ronald Ross, the malaria hero; and in literature," to Theodor Mommsen, the Roman historian. Fischer's diploma reads as follows : 17 231 EMINENT CHEMISTS OF OUR TIME CHIMIE V Academic Royale des Sciences de Suide dans sa seance du n novembre 1902, a decide conformement aux prescriptions du testament d'Alfred Nobel en date du 27 novembre 1895, de remettre le prix decerne cette annee " a celui qui aura fait la decouverte ou ^invention le plus importante dans la domain de la physique " a EMIL FISCHER en reconnaissance des merites eminents dont il a fait preuve par ses travaux synthetiques dans les groupes du sucre et de la purine. Stockholm, le 10 decembre 1902. Hj. Theel CHR. AURIVILLIUS If the sugars and the purines deserved the Nobel prize, no prize yet founded is big enough and important enough as a reward for Fischer's protein studies. In 1907 the Faraday medal of the English Chemical Society was presented to Fischer. This entailed a trip to England to deliver the Faraday lecture an invitation which had been extended once before in 1895, but which ill-health at the time prevented from accepting. The historic lecture, largely taken up with a discussion of the chemistry and significance of the three great classes of foodstuffs, was delivered in the theatre of the Royal Institution, on October i8th of that year, with Sir William Ramsay, president of the Society, in the chair. In presenting the medal Ramsay remarked that it was awarded " as a testimony of our great regard for you as our foreign member and of our affection for you as a man." Within seven years a bloody war was to twist affection into the deepest hatred. 232 EMIL FISCHER Sir Henry Roscoe, a star pupil of Bunsen in Heidel- berg, and for years professor of chemistry at Man- chester University, had this to say in proposing a vote of thanks to the Faraday Medallist: "I have had the good fortune to hear many Faraday Lectures. I re- member with pleasure the eloquence of Dumas; the charm of Wurtz; and the thought and beautiful diction of Helmholtz; but, Mr. President, I do not think that any of our Faraday Lecturers have awakened greater interest than the one to which we have just listened; and this, not only because Emil Fischer is a master of his subject, and because he has laid before us work mainly accomplished by his own inventive brain and his own able hands, but also because the subject of the application of synthetical chemistry to biology, which the lecturer has so ably brought before us, is one which at the present moment is exceeded in intere-st and import- ance by no other branch of the science, not even if I may be allowed, in the presence of the President, to say so by that of radioactivity. . . . When some years ago we learnt that Emil Fischer had synthesised the sugars, all chemists were loud in their expressions of satisfaction and admiration. 1 How much greater will these expressions be now when we learn what success has attended the apparently almost insoluble problem of the synthesis of proteins. ..." Since the time of Fischer's work various phases of pro- tein chemistry and protein metabolism have been pur- sued with much success by such men as Folin, Levene, Dakin, Jones, Osborne, Van Slyke and T. B. Johnson, in this country, Hopkins, E. F. Armstrong and Plimmer in England, and Kossel and Abderhalden in Germany. 1 " His (Fischer's) name," said Roscoe on the occasion of the Perkin Jubilee, " has the sweetest of tastes in the mouth of every chemist." 233 EMINENT CHEMISTS OF OUR TIME The significance of individual amino-acids in diet has been eloquently expounded by Abderhalden, and Mendel and Osborne, and the additional " vitamine " factors in diet a distantly related topic, but not to be confused with the amino-acid factor, have been put on a firm foundation by the labors of Funk, Hopkins and McCollum. There seems to be some foundation for the fact that the opening up of the Rockefeller Institute in New York City gave German scientists some very unpleasant moments. They were afraid that an institute, devoted entirely to research, and manned by talent second to none, would soon outstrip any university, where of necessity teaching, aside from research, required much attention. This led Ostwald, Nernst and Fischer to start an agitation for the endowment of some similar institute in Germany. The Kaiser gave the full weight of his authority to the scheme, and by his exertions managed to get considerable sums from wealthy Ger- mans. The Research Institute at Berlin Dahlem was the result. The initial meeting to celebrate the formation of the Kaiser Wilhelm-Gesellschaft zur Forderung der Wissen- schaften was held at the offices of the Ministry of Education in Berlin, on Jan. n, 1911. The principal address, Recent Advances and Prob- lems in Chemistry, was delivered by Prof. Fischer. With a graceful tribute to the far-sighted policy of the Germans in encouraging science, Fischer proceeded to show that such encouragement brought its own reward. Up to 191 1 sixty percent of the total number of Nobel prizes in chemistry had gone to Germans. 1 1 It needs perhaps to be emphasized here that, as Fischer him- self admits, this excellent German showing is not the result of superior German intelligence, but purely the result of far greater 234 EMIL FISCHER Fischer next briefly reviewed the important contri- butions of the chemist to our knowledge of the three classes of foodstuffs, the development of the dye in- dustry, the methods of extracting nitrogen from the air for use as fertilisers, and the manufacture of artificial indigo, india-rubber, camphor and " baekalite." l " The beakers and flasks of the scientific investigator," added Fischer, with a twinkle which always delighted his students, " are minute when compared with the vats employed by the chemical manufacturer. This relative difference in size is also borne out by the comparative wealth of these two classes of men." Turning to plant and pharmaceutical products, Fischer proceeded to exhibit a sample of pure chlorophyll, the work of Willstatter and drugs such as veronal and caffeine both the products of Fischer's genius. Then came this characteristic comment: " One tenth of this quantity [of veronal] would suffice to send this entire gathering into a peaceful slumber. But should the mere demonstration of this soporific coupled with this lec- ture of mine take effect on any susceptible persons present, there is no better remedy than the cup of tea which we are to enjoy later, for tea and coffee contains a chemical substance [caffeine] which stimu- lates the heart and nervous system." government encouragement than is given elsewhere. In England, France, and to a large extent, in our own country, the chemist and the scientist generally received no attention from statesmen until the outbreak of the present war. The disgraceful remunera- tion offered at colleges, and, with few exceptions, the poor facilities offered for research, have retarded every effort, and have resulted in the loss to universities of some of their best minds. This was before the war. Perhaps things will change now. Perhaps. iThis last is the discovery of Dr. Baekeland of New York. The " baekalite," as is now well known, resembles amber, and is used for such articles as necklaces, combs, cigar-holders, etc. 235 EMINENT CHEMISTS OF OUR TIME " Caffeine," proceeded Fischer, " was now obtained largely from uric acid, which, in its turn is a constituent of guano. 1 The chemist may apply to such substances the remark made by the Emperor Vespasian concerning the tax-money which came to him from an unclean source: non elet (it does not smell)." A sample of adrenalin, the active constituent of the suprarenal glands, which plays such an important part in the regulation of blood pressure, was also exhibited and its value discussed, and with characteristic German egotism, its isolation, chemical composition, as well as its synthetic production, were claimed for Germans. Not a word was said of Abel, of Johns Hopkins, the pioneer in this field, nor, while touching on the fasci- nating chapter of " hormones," or body regulators, was any mention made of the two immortals and insepar- ables, Bayliss and Starling, of University College, London. However, what followed smacks of the now celebrated " 2 and 75 percent." " A skin surface well charged with blood as for instance a red nose is instantly rendered quite pale on painting it with such a solution." " Unfortunately," proceeded Fischer, amid the shrieks of the audience, " it does not last." Next, and the last among the list of drugs, came the " 606," or salvarsan, the great discovery of Ehrlich, who, by the way, composed one of the audience at this lecture. The final phase of the discourse dwelt upon the re- markable development of the synthetic scents, which, even in 1911, gave rise to a production of over ten million dollars' worth, and which is now a serious com- petitor of natural flowers. A sample of ionone, the artificial violet scent, contained enough material, we 1 Uric acid is as important and characteristic an excrement of birds as is urea of man. 236 EMU FISCHER are told, " to envelop the entire avenue, Unter den Linden, 1 in an atmosphere of violet perfume." Samples showing scents of lily-of-the-valley, mock-orange, lilac, and, the greatest achievement of all, synthetic attar of roses, were also displayed. This last was truly a triumph of the chemist's skill. The natural oil from roses contains no less than twenty different substances. These were all isolated, then synthesised, and finally reunited in just those proportions which give us the pleasant odor of the much-prized rose. Fischer's researches into the carbohydrates, purines and proteins, is of such enormous importance that, at the repeated requests of the scientific public, they were published in book form in three bulky volumes, the first, Untersuchungen Uber Amino-Sauren, Polypeptide und Proteine (1899-1906), dealing with the proteins, the second, Untersuchungen in der Purin Gruppe (1882- 1906), with the purines, and the third, Untersuchungen liber Kohlenhydrate und Fermente (1884-1908), with the carbohydrates and enzymes. It is certain that in organic chemistry no three volumes of such far-reaching influence have ever before been published. Fischer's most recent work dealt much with the tannins, substances that play an important part in leather manufacture. Fischer's work, his influence as teacher and inspirer of men, raised the Berlin chemical laboratory to the first position among the chemical laboratories of the world. His fame attracted students from every quarter of the globe, and these flocked in such numbers to him that they soon counted in the hundreds, and special privat-docenten had to be appointed to take care of them. It thus came about that many of the men who 1 Berlin's principal thoroughfare. 237 EMINENT CHEMISTS OF OUR TIME had gone to Berlin to work under Fischer in reality worked under some of Fischer's privat-docenten, and, outside of the lectures, probably did not see Fischer himself more than two or three times during their three or four years 1 stay in the German capital. At one time or another H. Gideon Wells, the excellent pathologist of Chicago University, T. B. Osborne, of the Connecticut Experimental Station, and the foremost authority on vegetable proteins, and P. A. Levene, D. D. Van Slyke, and W. A. Jacobs, the well-known physiological chemists of the Rockefeller Institute, were his students. Of his many pupils Fischer considered Emil Abderhalden, now professor of physiology at Halle University, a Swiss by birth, the most gifted. Fischer's death is an irreparable loss to science. He is so much of our generation that one hesitates to use superlatives, but one is sorely tempted to speak of him as the greatest organic chemist of all times. References Part of the material has been obtained from private sources. The account of Fischer in the Nobel volume (i) has been of great service. Fischer's work on purines, carbohydrates and proteins has been published in book form (2, 3, 4). His address to the members of the English chemical society (5) contains much of interest. See also 6. A summary of Fischer's work on tannins has appeared in English (7). Enzymes are discussed in Dr. Harrow's article (8). 1. Anon.: Hermann Emil Fischer. Les Prix Nobel (Stockholm), 1902, p. 58. 2. Emil Fischer: Untersuchungen in der Puringruppe, 1882-1906 (Julius Springer, Berlin. 1907). 3. Emil Fischer: Untersuchungen iiber Kohlenhydrate und Fer- mente, 1884-1908 (Julius Springer, Berlin. 1909). 238 EMIL FISCHER 4. Emil Fischer: Untersuchungen u'ber Aminosauren, Polypeptide und Proteine, 1899-1906 (Julius Springer, Berlin. 1906). 5. Emil Fischer: Synthetical Chemistry in its Relation to Biology. Journal of the Chemical Society (London), 91 , 1749 (1907). 6. Emil Fischer: Recent Advances and Problems in Chemistry. Nature (London), 85, 558 (1911). 7. Emil Fischer: Synthesis of Depsides, Lichin-Substances and Tannins. Journal of the American Chemical Society, 36, 1170 (1914). 8. Benjamin Harrow: What are Enzymes? Scientific Monthly, March (1918), p. 253. 239 INDEX Names of persons are printed in italics. Abderhalden, 233, 234, 238 Abegg, 130* Abel, 236 Abraham, 115 Acetoacetic ester, 12 Acetylene, 136 Acheson, 148 Adrenalin, 236 Agassiz, 213 Aldehydes, 221 Alizarin, 8, 12 Althoff, 190 Alum in baking powders, 213 Aluminum, 149 Amino acids, 230, 234 Anderson, 44 Aniline, 6 Aniline purple. See mauve. Anthracene, 9 Argo, 145 Argon, 48, 144 Armstrong, E. F., 233 Armstrong, H. E., 13 Anhenius, XII, XIV, 91, 92, 93, 95, 99, i H-I33, 153, 167, 168 Art, Mendeleeff on, 34 Asymmetric carbon atom, 93. See stereo-chemistry. Atomic theory, 165. See Dai- ton. Atomic weights, 24, 25, 62-64, 66, 67, 68, 69, 70 Atoms in Space, Structure of (book by van'tiHoff), 85-88, Auwers, 191 Avogadro, XI, XIV, 64 Ayrton, Mrs. Hertha, 168 Badische Analin-und-Soda-Fab- rik, 6, 15 Baekeland, 14, 235 Baeyer, frontispiece, 6, 15, 100, 101, 180, 181, 183, 184, 185, 190, 191, 193, 217, 219, 220, 221, 223 Baeyer factory, 8 Baker, 145 Balard, 142 Bancroft, 93, 102, 105, 108, 122, 130 Baxter, 69 Bayliss, 236 Bechamp, 6 Beclere, 139 Becquerel, 160, 161, 168 Behring, von, 97, 129 Behal, 14 Beilstein, frontispiece, 15 Benjamin, 215 Benzene, 12 Benzoate of soda, 212, 213 Bernstein, 178, 179 Bernthsen, 15, 70 Berthelot, 35, 50, 115, 13^, 144, 150 Berthollet, 135, 218 Bertrand, 56 Berzelius, 70, 99 240 INDEX Biltz, 70 Biological chemistry, 128-129 Bluntschlij 184 Bodenstein, 130 Bolley, 181 Boltwood, 163 Boltzmann, 120, 135 Bouis, 145 Boy/e, XI, XIV Brandt, 23 Brauner, 70 Bredig, 74, 93 Brooke, Rupert, 217 firi/W, 12, 15 Buchka, 187 Buchner, 70, 217, 227 Buckle, 89 Bunsen, 23, 178, 179, 190, 191 192, 193, 219, 233 Burton, 210 Butler ow, 24, 223 flyron, 39, 83, 87, 98 Caffeine, 222, 229, 235, 236 Cahours, 150 Com, 18 Co/of, Ramon y, 151 Calcium carbide, 136, 148 Cambon, 106 CannizzarOi XI, XIV, 15, 24, 64 Carbohydrates. See sugars Carborundum, 148 Caro, 9, 15 Catalyst, 226 Cathode rays, 160 ' Cayley, 31 Chancourtois, 29 Chandler, 16, 103, 104, 197 Chaudhuri, 58 Chemical constitution and physi- cal properties, 12 Chemical Dynamics (book by van't Hoff), 80, 90-92, 93 Chevreul, 35, 218 Chit tendon, 212 Chlorophyll, 235 Ciamician, 15, 130 Clarke*, 105 Classification period (in chem- istry), XI Clausius, n, 115, 116, 117 Cleve 112, 116, 117 Coal tar, 4, u, 13 Coal tar dyes, 3-8 Cohen, E., 93, 95, 102, 108, 120, 132 Cohn, G., 183 Cooke, 60, 61, 62, 65, 197 , Copernicus, 35 Copley medal, 31, 150 Cossa, fronitspiece Coumarin, iz, 12 Courtois, 142 Crafts, 1 08 Crawford, 176 Crookes, 3, 49, 154, 160, 164, 217, 225 Cunningham, 176 Curie, Madame, XHI, XIV, 29, 147, 155-176 Curie, P., 135, 159, 168, 169-170, *72 Cushman, 69 Dahlgren, 170 Dakin, 224, 233 Dalton, XI, Xm, XIV, 64, 100, in, 165 Dana, 208 Darwin, 17, 29, 117 #<">#, 93, 143, 168 - Davy medal, 13, 26, 31, 50, 75, 93, 150 241 INDEX Dawson, 130 Day, 105 Debienne, 163. Debray, 144 Deherain, 138, 139, 140 Demuth, 191 Descartes, 35 Deventer, van, 93, 120, 130 Devitte, St.-Claire, 135, 141 -De F"0, 57 Dewar, 144 Diamond, artificial production of, 136, 146-148 Disintegration theory (of ra- dium), 164 Dissociation, theory of electro- lytic, in, 113-119, 121-123, 130-131 Ditte, 150 Dixon, 72, 145 Dluska, 175 Dobbie, 44, 45, 56 Dobereiner, 25 Domidoff prize, 24 Doremus, 199 Dorp, van, 180 Duisberg, 15 Dumas, 25, 35, 135, 140, 233 Duppa, 12 Eb stein, 189 Edlung, 112, 118, 124 Ehrhardt, 15 Ehrlich, 129, 159, 217, 236 Electric furnace. See furnace, electric Electrolytic dissociation. See dissociation, theory of Electrons, 160, 163 Eliot, 108, 197 Energy of the future, 165 Engelbach, 219 Enzymes, 97, 225-228, 231 Erlenmeyer, 178, 193 Etard, 139 uter, 130 Evaporation and dissociation (Ramsay and Young), 46 Ewan, 93 Eykman, 93, 120 Fahlberg, 215 Fajans, 74 ttz/fc, 128 Faraday, 8, 12, 35, 76, 113 Faraday medal, 31, 50, 72, 130, 232 Fats, 218 Fehling, 180 Fenton, 223 Ferguson, 44 Ferments. See enzymes Fischer, E., XIII, XIV, 13, 24, 70, 94, 98, 99, 128, 191, 193, 194, 217-239 Fischer, H., 224 Fischer, O., 185, 221, 222 Fittig, 42, 43, 204 Fitzgerald, 47 Fluorine, 136, 142-145 Folin, 71, 233 Food. See fats, carbohydrates, proteins, amino acids, vita- mine. Foote, 147 Foster, 135 Foundation period (in chem- istry), XI Franklin, 197 Franklin medal, 75 Fremy, 138, 143, 144 Fried el, 150 Friedlander, 14 Fuchsine. See magenta 242 INDEX Funk, 234 Furnace, electric, 136, 146, 147, 148, 150 Fyfe, 57 Gabriel, 70 Galileo, 33 Garett, 40 Gases of the atmosphere. See inert gases of the atmosphere Gattennann, 187, 191 Gautier, 14, 145, 149 Gay-Lussac, 117, 123, 135, 143 Gegenbauer, 150 Geikie, 150 Germanium, 28, 29 Gibbs, Willard, 97 Gibbs (Willard) medal, 75, 132, 214 Gibbs, Wolcot, 61, 72, 108, 197, 199 Gibbs (Wolcot) Laboratory, 72, 73 Gilder sleeve, 207 Gilman, 207, 209 Gladstone, 12 Glucosides, 228 Glycine. See glycocoll Glycocoll, 12, 230 Goldenberg, 32 Goldschmidt, 93, 186 Gotyi, 151 Goodwin, 107 Graebe, 9, 70, 180, 183, 193, 220 Graham, 35, 42 Gray, 55 Green, 18 Grimaux, 150 Guanine, 222 Guldberg, 45, 130 Gunning, 57 Hole, 104 /fa//, C. M., 149 Hall, T., 2 Holler, 14 Hamburger, 130 Hantzsch, 186 Harcourt, 52 Harden, 194 /fare, 197 Harrow, 195, 239 Hasselberg, 54 Hastings, 17 Hehner, 56 Helium, 49, 50, 53, I44i 163, 166 Helmholtz, 98, 99, 122, 124, 125, 126, 178, 190, 233 Helmholtz medal, 98 Hempel, 65 Henderson, L. J., 69 Hermann, 87 Herter, 212 /ferfy, 210 /ferfc, 6 /feyse, 185 /fi//,6i, 108 Hillebrand, W. F., 16, 48, 105 /fifziff, 183 /f/e/f, frontispiece tfq^, van'/, frontispiece, XII, XIV, 37, 39, 45, 47, 70-109, in, 114, 118, 119, 120, 121, 123, 131, 132, 158, 168, 188, 219,223,224 Hoff, van't, in America, 102-108 Hofmann, 3, 7, 178, 190, 225 Hofmann medal, 13, 151 Hopkins, 234 Hortsmann, 122 Hubner, 185 Huggins, 31 Huxley, 88, 117, 122, 127, 207 243 INDEX Hydroxylamine, 221 Iinmuno-chemistry, 129 Indigo, 267 Indol, 222 Inert gases of the atmosphere, 48, 52, 144. See argon, hel- ium, neon, xenon, krypton Inorganic chemistry, XII lonization. See dissociation, theory of electrolytic Jackson, 61, 108 Jacobs, 238 Jacob son, igi Joffe, 1 80 John, 98 James, 137, 138 Jannasch, 65, 187, 191 Johnson, S. W., 197 Johnson, T. B., 233 Jones, Grinnel, 69 Jones, H. C., 98, 102, 104, 109, 122, 130, 132, 210 Jones, W., 233 Jorgsneen, frontispiece, 15 Joule, 100 Jungfleisch, 150 Kohlenberg, 122 Kappeler, 181, 184, 186 Kayser, 50 Kekule, XIV, 82, 84, 186, 193, 219 Kelvin, 14,42,50,124,126, 168, 174 Ketones, 221 Kirchhoff, 178, 190 Klaudy, 101 Klein, 185 Klingeman, 15 Knox, 143 Koch, 7 Kohler, 210 Kohlrausch, 118 Kolbe, 87, 88, 89, 93 Konig, 185 Kopp, 178, 182, 193 Kossel, 98, 128, 233 Kouindji, 34 Kropotkin, 33 Krypton, 52 Kundt, 93 Kutorga, 23 Lactic acid, 224 Ladenburg, frontispiece, 37, 70, 183 Lampe, 70 Landolt, frontispiece, 70, 98 Langevin, 169, 176 Lavoisier, XI, XIV, 35, 71, 92, 135 Lavoisier medal, 14 Law of mass action, 130 Lead. See radioactive lead Lebeau, 153, 1 54 Le Bel, XIV, 80,85,86,93,150, 223 Le Blanc, 130 Le Chatelier, 130, 145, 149 Lecoq de Boisboudron, n Lembert, 74 Lemoine, 145 Lenard, 150 Lenz, 23 Leuckardt, 187 Levene, 233, 238 ' Lewis, 69 Liebermann, 9, 15, 70, 180, 183, 190, 193, 195, 220 Liebig, XII, 123, 203, 219, 221 Life, origin, of, 125-128 Lippmann, 158, 159 244 INDEX Lisset, 17 Lister, 150 Lockyer, 49, 50 Lodge, 121, 174 Loeb, J., 102, 103, 119, 127, 128 Loeb, M., 72 Long, 212 Longs faff medal, 52 Lorentz, 231 Louyet, 143 Lowry, 65 Ludwig, 180 Lugan, 141 Lunge, 15 224 117 McCollum, 234 McKee, 210 Maeterlinck, 170 Mahlmann, 187 Magenta, 7, 221 Mallet, 197 Maltby, 103 Mai thus, 117 Morass e, 180 Marconi, 6 Matter, structure of, 165 Mauve, XIV, 4, 1 1 Meldola, 13, 14, 16, 17 Mendel, 234 Mendeleeff, frontispiece, XII, XIV, 19-40, 5i i"i 135 Meyer, L., 29 Meyer, R., 195 Meyer, K., XH, XIV, 44, 65, 145* i77-i95 220, 221, 224 Meyer and Jacobson's " Lehr- buch" (book), 188 Meyer hoffer, 93, 96, 97 Michael, 108 Michler, 183 Millikan, 65 Milner, 205 Mitscherlich, 35 Moissan, #., XH, XIH, XIV, 131* 135-154 Moissan, L., 142, 152, 153 Molwo, 17 Mommsen, 231 Morgan, 122 Morner, 45 Morris, 78 Morse, 104, 208, 210 Moseley, XII, XTV, 64, 65, 217 Munsterberg, 108 Ate/, 102, 105, 107 Neon, 52 Nernst, 16, 70, 234 Newlands, 25, 26, 116 Newton, 35 McAo/s, 16 Nieme, 15 Niton, 55, 166 Nitrobenzene, 6 Nitro compounds in the ali- phatic series, 181, 183 Afofce/ prize, 53, 75, 77, 97, 131, 151, 169, 170, 231, 232, 234 Norris, 210 Noyes, A. A., 95, 122 Noyes, W. A., 210 Nucleoproteins, 229 Oil fields in Baku, 30 Organic chemistry, XII, 217, 218 Ormdorff, 210 Osazone test for sugars, 220 Osborne, 234, 238 Osmotic pressure, 92 Ostrogradsky, 23 Ostwald, XH, 41, 47, 58, 67, 92, Il6, 117, Il8, 120, 121, 122, 130, 131. 132, I45 I53i 234 245 INDEX Oudeman, 82 Panspennia, 124 Pasteur, 79, 159, 194, 226, 227 Pavloff, 19, 54 Pellew, 103, 104 Periodic law. See periodic sys- tem Periodic system, XII, 19, 25-29, 30, 31, 40, 64 Perkin, A. G., 17 Perkin, G. F., 2 Perkin, W. H., XH, XIV, 1-18, 36, 135, 220, 221, 225, 230, 233 Perkin medal, 16 Perkin (jun)., W. H., 17 Perkin's synthesis, n Perrin, 169 Petroleum, origin of, 148 Pe tier son, 54 Pettijohn, 103 Pfeffer, 92 Phase rule, 97 Phenylhydrazine, 220, 221, 224 Physical chemistry, 47 Physico-chemical period (in chemistry), XH Physiological chemistry. See biological chemistry Pickering, 108 Pinner, 70 Pirogoff, 23 Pitchblende, 161 Planck, 70, 94 Pletnoff, 22 Plimmer, 233 Plique, 138 Poincare, 159, 170 Polonium, 162, 174 Polstorff, 187 Polypeptids, 231 Pomeroy, 13 Priestley, 197 Principles of Chemistry (book by Mendeleeff), 29 Proteins, 218, 229, 230, 231, 233 Punch, 8 Purin, 229 Quincke, 191 Radiation pressure, 124 Radioactive lead, 74, 75 Radio-activity, XIII, 53, ^55. See radium Radium, 53, 123, 160-169. See radio-activity Radium emanation. See niton Raleigh, XIV, 31, 48, 50, 54, 76, 117 Ramsay, frontispiece, XII, XIV, 16, 29, 36, 41-58, 74> 98, 122, 131, 144, 151, 153, 154, 158, , 163, 168, 174, 204, 205, 217, f 224, 232 Raoult, 92, 100, 112, 117, 119, 123 Rare gases of the atmosphere. See inert gases of the atmos- phere Reed, 210 Regnault, 23 Reicher, 93, 120 Remsen, XIII, XIV, 16, 55, 105, 114, 197-215 Reusch, 43 Reymond du Bois, 179 Richards, H. M., 59 Richards, T. W., XII, XIV, 29, 59-78, 95, 102, 107, 108, 122 Richards, W. T., 59 Riess, 152 Rilliet, 181 Rockefeller, 106, 107 246 INDEX Rockefeller Institute, 234 Romburgh, 14 Rontgen, 97, 150, 160 Roosevelt, 108, 211 Rosaniline, 7 Roscoe, 233 Rose, 35 219 Roses, oil of. See scents, syn- thetic Ross, 231 Roux, 126 Rowland, 207 Royal College of Science, 2 Royal medal, u, 31, 150 Rumford medal, 150 Rupe, 14 Ruprecht, 23 Rutherford, 75, 163, 164, 166, 176 Sabatier, 149 Saccharin, 208 Sandmeyer, 186 Sawitsch, 23 Scents, synthetic, 236, 237 Schafer, 127 Scnar, 181 Scheele, 142, 143 Scnzff, 15 Schmidt, 120 Sc hot ten, 14 Schukenberger, 57 Schulze, 181 Schurman, 105 Schutzenberger, 150 Shields, 45 Side-chain theory, 129 Siredey, 139 Sklodowski, 156, 175 S/yfce, Z>. D. van, 128, 233, 238 Smith, A., 106, 107, 109, 132, 176 Smifn, . F., 197 Smith, T., 122 Smifn, W., 193 Smithells, 47 Soddy, 53, 58, 74, 75, 95, 163, 164, 176 Sokoloff, 19 Solution, van'/ /fo^s theory of, 92,98 Solutions (book by Mende- leeff), 22 Sonnenschein, 177 Specific volumes, 23 Spottiswoode, 31 S^rma, 93 Starling, 236 Sfas, 64, 70 Stassfurt deposits, van'* Hojf's work on, 96, 97 Stereo-chemistry, 79, 80, 85-88, 89, 93, 188 Stieglitz, 106, 132 Stock, 153, 154 Stockton, 60 Strecker, 204 Sugars, 218, 220, 221, 222-224, 225, 228 Surface tension and molecular weight (Ramsay and Shields), 47 Sylvester, 207 Takayama, 15 Tammann, 130 Tannin, 237 Tartaric acid, 12 Taylor, 130, 212 TTiee/, 232 Thenard, 143 Theobromine, 222, 229 Thiophene, 184, 187 Thomson, 116, 151, 160, 165 Thorium, 161 247 INDEX Thorpe, frontispiece, 40, 191, 194, 195 Tiemann, 98 Tilden, 40, 58, 130, 214 Toll ens, 190 Toxin and anti-toxin, 129 Transmutation of elements, 53, 166 Traube, 92 Trovers, 52 Triphenylmethane, 222 Troost, 150 Trowbridge, 108 Tyrian purple. See mauve Uranium, 160 Urea, XIV Uric acid, 222, 229, 236 Valson, 117 van't Hoff. See Hoff, van't Vapor Density (Victor Meyer's method,) 183 V enable, 40 Verguin, 7 Veronal, 235 Vesque, 139, 140 Vitamine, 234 Volhard, 203 Vries, Hugo de, 131, 153 Waage, 130 Walden, 40 Wallace, 29 Wallach, 84, 186, 191 Walter, 139 Warburg, 70 Ward, 135 Watts, 103, 194 Wegscheider, 130 , #. Gideon, 238 , W., 103 z, 162 Wiley, 16,212 Will, 14, 98 Williamson, 117 Willstatter, 220, 235 WinJder, frontispiece, 28 Ms//cem/s, 79, 86, 87, 89, 181 Witt, 70, 98 Witte, 32 Wohler, XH, XIV, 185, 203, 204, 205, 219 Woskrensky, 23 burster, 181, 182 Wurtz, 57, 85, 233 X-rays, 160, 164 Xanthine, 222 Xenon, 52 Young, 45 Zeeman, 231 Zincke, 219 248 14 DAY USE TO DESK PROM WHICH BORROWED LOAN DEPT. B3ttSKfeJI CIRCULATION DEPT. LD21A-40m-8,'71 (P6572slO)476-A-32 General Library University of California Berkeley LD21-100m-7,'39(402s) re (7050 U. C BERKELEY LIBRARIES THE UNIVERSITY OF CALIFORNIA LIBRARY