Clio and chemistry: A divorce has been arranged - ACS Publications

have mostly been superseded by subsequent work, and as ... man and jealous of his priority; he did not invariably give credit where it was due to his ...
3 downloads 0 Views 5MB Size
Clio and Chemistry: A Divorce Has Been Arranged

opinion

In a recent article (provocatively titled "Should the History of Science be Rated X?")Stephen Brush has argued oersuasivelv that historians of science have found out that noted scieniists often hehave in ways that are nor very good models for present students to follow (11. This article takes up this theme, in the specific context of the history of chemistry, and applies it to the ways in which the historical aspects of chemistry may be used in the University curriculum. For simplicity of identification, following Brush's lead, let us call two such ways G (for General) and R (for Restricted). These terms have the following meanings in this context. The G approach, which is one rather widely followed by instructors at all levels, is to sprinkle historical material with a greater or lesser density (rather like the raisins in the Thomson "raisin pudding" model of the atom (2)), throughout a course intended to teach chemistry. Thus we mav illustrate a discussion of introductory stoichiometry andatomic theory by mentioning ~ a l t o n ' satomic theory and its corollary, the law of multiple proportions. The gas laws elicit a description of Robert Boyle performing tests on "the spring of the air." Optical activity, in the organic course, brings in Pasteur and the resolution of tartrate salts, and so forth. The R approach envisages trimming to the minimum, and perhaps even to zero, such historical anecdotage in courses intended to teach chemistry and instead offering to students interested in the background of the subject, and who dreadv have a reasonablv develoned understandine of chemistry, a genuine course in the history of chemistry. This would undertake a detailed examination of how chemists of all eras actually did behave in developing the theories and laws with which their names are associated. There is probably no basis for any strong objection among chemical educators to the presence of an elective R-approach course in the chemistry curriculum. Those students who have a genuine interest in such topics as how scientific ideas havetheir genesis, how they develop and mature. what kind of reception scientific novelty receives from the icientific establishment, and how the tone of a given era influences the kinds of science practised in that era should be offered the opportunity of exploring these topics and related ones, a t some leisure, in the context of a course i n t h e history of chemistry. One could even, in these days of acute awareness of the interactions between science and society, make a persuasive argument for requiring such a course for chemistry majors. What must be argued here, though, is the inappropriateness of the G-approach in a course that intends to teach chemistry. T o do this we must examine the objectives of such courses and decide whether we have the time or the resources to include in them accurate historical accounts of the development of the subject. I assume that none of us wishes to mislead students by presenting inaccurate descriptions or analyses of chemistry's origins. We do not wish to be guilty, either by sins of omission or by sins of commission, of falsifying our accounts.

-

Presented at the Spring Meeting of the Southern Section of the California Association of Chemistry Teachers, Claremont Colleges, March 15,1975.

The prime objective of courses which teach chemistry is to indoctrinate students with a particularly useful and productive puzzle-solving technique. This may be a controversial view of what chemistry courses do, hut I believe it is an accurate one. We aim, to appropriate Thomas Kuhn's phrase, (3), t o produce students capable of at best doing, and at least appreciating, those activities termed "normal chemistry." T o quote Kuhn, " 'Normal Science' means research firmlv based upon one or more past scientific achievements, achievemknts that some scientific communitv acknowledees for a time as supplving the foundation for-its further practice." The achi&emer%s of "normal chemistry" are set down and formalized as dogma in textbooks of chemistry. Kuhn has also drawn attention to the striking degree to which education in science, in contrast to education in other creative fields, is conducted via textbooks which are designed solely for students. In many other fields students a t the beginning college level are left to grapple, perhaps with the aid of critical guides, with the original works of the acknowledged masters of the field. But chemistry students come relatively late to the literature of their field, and then usually encounter i t only in the context of a narrow individual research project or literature search assignment. The chemistry student can hardly be given the enormous assignment of reading the classic works of his field-and that is as it should be. For these classics have mostly been superseded by subsequent work, and as A. N. Whitehead remarks "A science that hesitates to forget its founders is lost." Since chemistry courses have as their primary goal the indoctrination of students with the dogma of "normal chemistry," and since the classics of chemistry have little to do with modern chemistry, cannot we then use the classics in another wav in our classes? Can they not be used as moral and technical exemplars to illustrate a scientist's credo and modus o ~ e r a n d i ?A modern chemist (Franklin Long) has stated (4) what he believes to be the shared characteristics in the areas of philosophy and method, of an (idealized?) community of scientists as follows to perform our scientific studies as honestly and as free from bias as we can (b) to publish our results openly and in a manner which subjects them to the critical appraisal of fellow scientists ( e ) to respond honestly to criticism and correction and be prepared to change our ideas if they do not stand up in the broader scientific community (d) to be acutely aware of the universality of scientific truths and to avoid therefore parochial and chauvinistic interpretations and analyses (e) to strive mightily to separate, in our own mind and in our presentation to others, the facts as we believe we have discovered them from our personal opinions or interpretations. (a)

Can we use examples from the history of chemistry t o illustrate these principles and to show how great scientists function? No doubt we could, but we would have to be careful in selection; and we can find many among the great chemists who violated several, if not all, of the cited precepts. Long's view of a scientist's commitments is, of course, a highly idealized one, and one which we, as instrucVolume 52, Number 10, October 1975 / 645

tors of chemistry, might choose to present to our students as a model to emulate. But it would be disingenuous for us to maintain that all, or even a majority, of those great chemists whose work we all acknowledge as among the milestones of chemical progress, consistently lived up t o this model. Let us consider a few episodes in the history of chemistry, to illustrate the general maxim that many great scientists were far from these idealized models. This is in no sense an attempt to 'debunk' these scientists, or to cast doubts on the validity of their achievements. The object here is simply to point out the dangers of drawing too freely on historical examples and figures in chemistry courses. In doing so, one runs a considerable risk of creating or perpetuating a mythology of chemistry. Antoine Lavoisier, more than any other chemist, deserves the title of "Father of Chemistry." His brilliant perceptions on the nature of combusion, and the significance in it of Joseph Priestley's "dephlogisticated air," led to the overthrow of the phlogiston theory and the establishment of a new and more rational chemistry. But there are shadows lying across these achievements. Lavoisier was a proud man and jealous of his priority; he did not invariably give credit where it was due to his predecessors, or even to those whose ideas were the direct inspiration of his own. And he was not above tampering (moderately) with history when it suited his purposes. For example in September 1774, Lavoisier received a letter from Scheele detailing some of the latter's work on oxygen (5) (not published openly until 3 years later); in October 1774, Priestley accompanied Lord Shelburn. his natron. to Paris and met Lavoisier and, ac' s account (6) Priestley then mencording t; ~ r i e s t e ~'later tioned his experiments on heating mercuric oxide to Lavoisier. Early in 1774, the French chemist Bayen published, in a journal we know Lavoisier read (7), papers on the materials produced by heating mercuric oxide. Lavoisier never acknowledged Bayen's work, and we find him writing (8) of his other contemporaries' discoveries of oxygen in the following off-hand way: "This species of air was discovered almost a t the same time by Mr. Priestley, Mr. Scheele, and myself." Perhaps the experiments on the oxygen-hydrogen reaction are an even clearer example. After some initial experiments by Priestley and Warltire, Cavendish established the nature of the reaction between hydrogen and oxygen to vield water (thourh he interpreted the process in terms of the phlogiston theory) in e a i y 1783 ( 9 ) : ~ h o r t l ~thereafter Blagden, Cavendish's assistant, visited Paris and discussed these experiments with Lavoisier (9). Lavoisier, with his associate Laplace. immediatelv. repeated Cavendish's ex. periments, and extended them in an imaginative way, and read a paper to the Academie des Sciences in November 1783 which did not mention the incidental fact of Cavendish's priority (10). (Incidentally, Lavoisier's experimental results, gathered in haste, were substantially inferior to those of Cavendish). Lavoisier also changed the historical record when it suited his DUIDoSe. Two instances of this will suffice. In the well-knbwn Easter memoir discussing his experiments on heating mercuric oxide (II), Lavoisier wrote in the version published in May 1775 the principle which unites with metals during calcination, which increases their weight, and which is a constituent of the calx is [:I neither one of the constituent parts of the air, nor a particular acid distributed in the atmosphere, that it is the air itself entire without alteration, without decomposition even to the point that if one sets it free after it has been so combined. it comes out more oure. . . more respirable, if this expression may be permitted, than the air of the atmosphere and is more suitable to support ignition and combustion In the version written for the volume of the Academie's memoirs dated 1775, hut not published until 1778, Lavo646 / Journal of Chemical Education

isier amended his thought substantially and describes this air as nothing else than the healthiest and purest part of sir, so that if air, after entering into combination with a metal, is set free again, it emerges in an eminently respirable condition, more suited than atmosphericair to support ignition and combusion. Lavoisier's tendency to change his recorded views, without explicitly commenting on the change, is also seen in "The Curious Episode of the Sealed Note" (which could almost pass for the title of a Sherlock Holmes mystery (12)). In a note deposited with the secretary of the Academie in November 1772.. (a . not uncommon procedure for claiming scientific priority a t the time) Lavoisier reported on the substantial gains in weieht he had noted in the combustion of sulfur orphosphoru;in air, and the relevance of this to the general prohlem of combustion and calcination. He concluded, in the original version of the note, with an unusually frank observation This discovery would seem to me to be one of the most interesting that has been made since Stahl and since it is difficult not to droo a hint of it to friends in conversation. which mieht .. out . them on the rra) to the truth. 1 thought it best tolcaw this note withthe Secretary of the Academy until I publish my experiments. There we see the true concern of Lavoisier coming through, his fear of being scooped by his French colleagues. But in the "official" version of the note prepared later by Lavoisier himself for subsequent publication, the tone is different: "This discovery appearing to me as one of the most interesting that has been made since Stahl, I thought to assure myself of priority by depositing the present note with the Secretary of the Academy, to remain secret until I publish my experiments." And he justifies his concern for priority by appeal to a patriotic argument! In 1792, he wrote I was young; I had to take precautions to ensure my priority in the discovery. There was, at that time, regular correspondence hetween the scientists of France and of England; there existed, hetween the two countries, a sort of rivalry which gave importance to new experiments, and which sometimes led writers of one or other countrv to disoute about their true discoverer. That is whv I thou& I shouid deposit the secret note an November 1st. l f 7 2 , with the Secretary of the Aead6mie. ~~~

Lavoisipr's undersrandnhle initial concern for keeping his discoveries for a time from his French colleagues and rivals has become, perhaps under the stress of historical changes (by 1792 the Revolution had come, and France was on the eve of war) a patriotic desire to keep his discovery from the English. This is a fine model for our students of open publication and discussion of results; of care in acknowledging prior work in a field; and of a scrupulous regard for the sanctity of the record. John Dalton, to whom we owe the Atomic Theory, which was certainly the most important single theoretical development in chemistry in the 19th century, is another chemist who Dresents certain ~ r o b l e m sin interpretation and a m preciation. Dalton can be categorized as a Pythagorean investieator-one who consisteutlv. soueht in his work simple integral relationships in fields as diverse as vapor pressure, the expansion of liquids, the laws of cooling, and the solubility of gases (13). I t was probably his work in this last area that led directly to the atomic theory. A well-known corollary of the atomic theory is the Law of Multiple Proportions and there has been considerable speculation among historians of chemistry as to whether the Law, as based on experimental observations, preceded the atomic theory or pokdated it. Some of ~ a l t o n ' sown early reports would suggest that the Law preceded the theory; thus he concludes, after a series of investigations on reactions be-

tween common air and nitrous gas (nitric oxide) that oxygen joins with nitrous gas sometimes in the weight proportion of 1.7 to 1, and other times in the proportion of 3.4 to 1, apparently a nice illustration of multiple proportions. However. Nash has shown that the ratio of 3.4 to 1 is extremely difficult to achieve experimentally (13), and Dalton was not renowned for his exoerimental skill! Partindon (14) has argued that the 3.4 to i ratio, rather than being an experimental value, is instead a rounded-off number calculated by Dalton as a result of his conviction of the correctness of the atomic theory and the Law of Multiple proportions. The adjustment of data to fit the expectations of a theory is not, of course, a phenomenon restricted to chemistry. Two recently discussed examples by eminent scientists in other fields are some of Gregor Mendel's data on heredity and genetics (15); and certain of Newton's calculations in the "Principia" on the orbit of the moon and other problems (16). As Westfall puts i t (16): "No one can manipulate the fudge factor quite so effectively as the master mathematician himself." Dalton also provides an interesting test of another widely held ideal of science. that scientists are, as a erouo, ooenminded, and welcome criticism of their work and the i r e sentation of opposing views. Indeed the late J. Robert Oppenheimer wrote a hook on his own scientific philosophy (17) and titled it, significantly, "The Open Mind." Dalton did not have an open mind. The most influential example of his closed-mindness was his steadfast opposition first to Gay-Lussac's Law of combining volumes, and then to the deductions Avogadro drew from Gay-Lussac's Law. Dalton's opposition was based in part on a distrust of GayLussac's experiments, which Dalton himself lacked the technical skill to duplicate. "The truth is, I believe, that gases do not unite in equal or exact measures in any one instance; when they appear to do so, it is owing to the inaccoracy of our experiments (18). But fundamentally his opposition was more deen-seated and lav in his earlv work on gas densities which ied him to conclude that particles of different eases (which we would interoret as the effective volume occupied per molecule) must he of different sizes. Thus rejection of Avogadro's hypothesis implied rejection of Gay-Lussac's law. Though Berzelius lamented "I should have thought, rather, that [Gay-Lussac's] experiments are the most heautiful proof of the probability of the atomistic theory," Dalton would have none of it, and his steadfast opposition helped plunge the whole question of the determination of atomic weights into a twilight zone which endured for sixty years. The truth is, that when faced with a challenge to accepted ideas, chemists are as closed-minded as any other group with vested interests. When Helmholtz presented his ideas on the conservation of energy, they were strongly opposed, in part because he was outside the scientific establishment, and he commented (19): "The greatest benefactors of mankind usually do not obtain a full reward during their lifetime; new ideas need the more time for gaining general assent, the more original they are." But Helmholtz himself was no better when i t came to aopraising other peoples' new ideas. In 1879 the young M ~ X Planck oresented. in his doctoral thesis, a novel treatment of the second law of thermodynamics and he observed (19) None of my professors a t the University had any understanding of its contents. I found no interest, let alone approval, even among the very physicists who were closely connected with the topic. Helmholtz probably did not even read my paper a t all. Kirchhoff expressly disapproved . . . I did not succeed in reaching Clausius. He did not answer my letters and I did not find him a t home when I tried to see him in person a t Bonn.

As Planck wisely says, almost echoing Helmholtz: "A new scientific truth is not usually presented in a way that convinces its opponents; rather, they gradually die off and

a rising generation is familiarized with the truth from the start." When Otto Hahn described the detection by radiochemical methods of unweiehahle amounts of radioactive elements, he had an unexpected reaction from a distinguished organic chemist in his audience (19)

-

At my inaugural lecture in the spring of 1907, [Emil] Fischer declared that somehow he could not believe those things. Far certain substances the most delicate test was afforded by the sense of smell, and no more delicate test could be found than that!

In 1845 John James Waterstoo, a rather obscure instructor of the East India ~ o m ~ a n y ' s m a r i t i mschool e at Bombay, submitted for publication to the Royal Societv in London a paper "On the physics of media that are composed of free and elastic molecules in a state of motion.'' This paper contained an extended treatment of the kinetic theory of gases, including derivations of the gas laws, and of mean square velocity (20). I t anticipated Kronig and Clausius's papers on the subject by over ten years, and Maxwell's by fifteen. It was not accepted for publication, though a brief and uninformative abstract was puhlished in 1846. Lord Rayleigh eventually rescued the paper from oblivion and published it in 1892. One of the anonymous referees of the Royal Society had written "the paper is nonsense, unfit even for reading before the Society." A second referee noted: "The orieinal itself involves an assumotion - orinciole . which seems to me very difficult to admit and by no means a satisfactory basis for a mathematical theory." As ~ a ~ l e i remarked gh (20) The history of this paper suggests that highly speculative investigations, especially by an unknown author, are best brought before the world through some other channel than a seientifie society, which naturally hesitates to admit into its printed records matter of uncertain value. Perhaps one may go further and say that a young author who believes himself capable of great things would usually do well to secure the favorable recognition of the seientific world by work whose scope is limited, and whose value is easily judged, before embarking on greater flights.

J. B. Haldane's views are equally pungent (20) "It is probable that, in the long and honourable history of the Royal Society, no mistake more disastrous in its actual eonsequences for the progress of science . than the rejection of Waterston's papers was ever made. The papers were foundation stones of s new branch of scientific knowledge, molecular physics, as Waterstan called it, or physical chemistry and thermodynamics as i t is now called."

. .. .

I t is not generally realized that the first reasonable model of the atom incorporating a quantum condition was proposed by Arthur Erich Haas in 1910, three years before thepuhlication of the famous Bohr atom model (21). Haas, a gifted young physicist with a historical bent, developed his model as a habitation thesis, in applying for a position in physics a t the University of Vienna, and used it to determine the correct value of the "Bohr" radius of the hydrogen atom, and an approximate value of the Rydberg constant. When Haas presented his ideas to his colleagues their reaction was, as you may by now suspect, unwelcoming. The fact that my achievement is generally recognized today only increased the pain I experienced throughout my later life, because of the fact that the narrowmindedness of the established leaders in physics stifled my initial attempts which might have led to great and possibly fundamental achievements. . . . In Vienna.. . I was a t first met only by disdain and even derision . . . Lecher thought he was particularly witty when he referred to the presentation during open discussion as a carnival joke [The lecture was given in February 1910 during carnival time]. Hasenbhrl [said] I could not be taken seriously since I naively mixed up seientifie fields which were completely unrelated, such as quantum theory (as something

Volume 52, Number 10. October 1975 / 647

thermodynamic) and spectroscopy (as something optical). Understandably, I became completely discouraged. At times, chemists' closed-minded attitudes have led to the production of some of the most entertaining polemics in science. Van't Hoffs' famous paper on the tetrahedral carbon atom was reprinted as a pamphlet, with the title "Chemistry in Space," and with a supportive and enthusiastic preface by Wislicenus, another pioneer in stereochemistry (22). Hermann Kolhe, who throughout his distinguished career had a distrust for what he regarded as uns u ~ p o r t e dtheorv (he even founded a iournal, which is still published, entitied Journal for practical chemistry) was incensed not onlv a t the Van't Hoff paper, hut also a t the support of ~ i s l i c e n u sand , wrote I would have ignored this work as I have done many others, had not a significant chemist taken it under his protection and recommended it as a worthy achievement. A Dr. J. H. Van't Haff, employed at the School of Veterinary Medicine at Utreeht, finds, so it seems, exact chemical research not to his taste. He has thought it more convenient to mount Pegasus (borrowed,no doubt, from the Veterinary School) end to proclaim in his "Chemistry in Space" how on his darinr.. flieht .. to the chemical Parnassus the atoms sopeared to be arranged in space . . . . To crittrize this paper in any &mil is impossiulc, because the play of the magination completel y tursakej the solid lround uf fact and is qum incomprehens~hle to the sober chemist.

In our view, of course, Van't Hoffs arguments (and those of Le Be1 put forth simultaneously and independently) are well grounded in experiment, and simply represent a beautiful extension of the structural theory of organic chemistry which was being realized a t that time. Perhaps the pinnacle of pragmatic obstinacy of the late 19th and earlv 20th centuries was achieved bv the distinLord Kelvin who, in short order, declared guished Ronteen's X-ravs a hoax: denied the observations of Ramsay a i d Soddy i n the p;oduction of helium from radium; rejected Maxwell's electromagnetic equations; and called Rutherford's nuclear model of the atom absurd. (19). A hint a t Kelvin's reasons for his opposition to these novel ideas may he gained from his own pronouncement: "I never satisfy myself until I can make a mechanical model of a thing. If I can make a mechanical model, I can understand." We can deduce from this that Kelvin had a fundamental belief that the Universe runs by classical mechanics; any phenomenon that seems to run counter to classical mechanics must, ipso facto, be incorrect or fraudulent. But this seeming limitation was also, of course, part of Kelvin's strength. In areas where classical mechanical arguments were relevant-thermodynamics, heat, sound, and some areas of electrical theorv-he was suoreme. The Dower of a successful idea may close a mind to novelty. Another topic which is rarelv aired in chemistrv courses. hut which is certainly significant in a historical context, is the important fact that alongside those observations and theories which we can now see as leading in the productive directions of chemistry (by which I mean towards those ideas currently accepted) were others which were later shown to be false, or which simply faded away because of lack of interest and support, and now lie buried as unexplained anomalies in the chemical literature. We tend in chemistry courses to present the progress of chemistry as an almost unchecked triumphal march; there may have been a few decisive battles along the way (phlogiston versus oxygen; constant composition versus variable proportions; atomic weights versus equivalents; vitalism versus organic synthesis; classical mechanics versus quantum theory) but when the smoke of hattle cleared, the right triumphed and all accepted its victory. Well we know it isn't a t all like that. 648 / Journal of Chemical Education

Vitalism did not vanish from organic chemistry overnight after Wohler's urea synthesis in 1828. We find Gerhardt writing, in 1842 (23) In fact no one has heen able to prepare uric acid from urea, . . . suear from alcohol.. . . Here chemistrv has been oowerless and. if m). guess is r~ght.will slwnys he so.. . chemical forces are opposed to the life force. . . Only the life iorce works by synthesis;11bu~lds up again the edifice torn down by chemical forces In the 1860's and 1870's the Chemical Society of London was the scene of intense debates on the subject of the existence of atoms. Doubts about the reality of Dalton's atoms recurred constantly throughout the 19th century; Davy, Faraday, Dumas and Kekule are just a few of the distinguished chemists of the period who expressed such doubt. "What remains of our ambitious incursion into the realm of the atom? Nothing. . . All we have gained is the conviction that chemistry has gone astray" (Dumas, 1826). "The question whether atoms exist or not has hut little significance from a chemical point of view: its discussion belongs rather to metaphysics . . . . I have no hesitation in saying that, from a philosophical point of view, I do not believe in the actual existence of atoms . . . . As a chemist, however, I regard the assumption of atoms. . . as absolutely necessary in chemistry" (KekulB, 1867) (24). As late as 1900 the great German physical chemist, Wilhelm Ostwald, taking his cue from the positivist philosophy of Ernest Mach, declared atoms to he an unnecessary hypothesis in chemistry. He finally changed his mind around 1906, convinced by the almost visible proof of the existence of molecules given hy studies of the Brownian motion, and by Einstein's theoretical study of this phenomenon. Doctrinal struggles in science can he as keen and prolonged as those in theology, and victory is seldom swift or clear cut. These e x a m ~ l e sargue forcefullv that the "truth" about many critical episodeiin the history of chemistry is a t least as c o m ~ l e xas the chemistrv itself and mav he much harder to present in a clear and &prejudiced manner. And this should lead teachers of chemistry to be extremely careful about the uses of historical examples in chemistry courses. In many respects there are two cultures, and there are elements in science and in history that are directly antithetical. It is crucial to science teaching to present phenomena and theories stripped of all association with person, time, or place; that is surely the great central dogma of science, that the phenomena, once the conditions of the experiment are established, are independant of the observer. But a historian seeks above all else that complex interplay of persons, social forces, and external conditions that led to a certain event. in a certain context. a t a certain time. Without these "trappings," as they would appear to the scientist, the event loses most of its sienificance for the historian. " . If chemists wish to use history in chemistry courses, it is only reasonahle to expect them to do their historical research with as much care and attention as they do their literature research for the chemical part of the course. I t is douhtful if this is done by one instructor in a thousand! But if instructors do not take these pains then the only honest alternative is to leave the history of chemistry to specialists and special courses and concentrate, in chemistry courses, on the job that they are supposed to do: teach chemistry. Literature CHed (11 Brush, S. G., Science, 183.11M 119741. (21 Lsgowski. J. J.,"The Structure of Atoms,"Houghton Mifflin Co., Boston, 1964, pp.

141 Lang,F.A., J. Chem. Edue.. 52.13 (197.51. 151 Dobbin, L.. "Colleaed Papen of Csrl Wilhelrn Sehoelo," London. 1931. p. 350. 161 Schofield, R. E., lEdifor1, "A Scientific Autohiomnhy of J m o h Priestlev."M.I.T.

(7) Gusrlae, H.. '"Lavoiaicr-The Cmeial Year? ComeU University Prear, Ithaca, New York. 1961. Chapter 2. R.,)I h V e l . Publieations Ine.. Now York. 1965, P. 36. (9) Ihdc, A. J.. "The Development of Modern Chemistw? Hsrpr & Row Publishers, New York, 1964, pp. 1-71. (10) Lavoiaicr, A. L., Obsrrvofionasur lo Phyaigue. 23.452 (1763). Harp. & R o w Publishers, (11) Ihde, A. J.. "The Development of Modem Ch.mist.y? New York. 1964. p. 67. (72) Cnerlsr R Chvmin 11961\. , , 7.10% ,~~~ (13) Nash,L.K..Isis, 47.101 (19561. (141 Partington,J.R..Ann. Sci. 4.246l1939). (15) van der Weerden, B.. Cenlourus. 12.275 (1968). (16) Westfall. R. S., Scirncr. 179.751 (1973). (17) Oppenheimer, J. R., "The Open Mind." Simon & Schustcr.New York. 1955. (18) Nssh, .,I K., "Herumd Case Histories in Experimental Science? (Editor Conanf J. (8) Lavoisier, A,, "Elements of Chemistry? (nonshlo?: Korr,

.~ . ~

B.1 Harvard University Press,Csmbridge. Mass..1957. Vol I, pp. 2745. (19) Barker, B.. Science. 134,596 (19611. (20) Bmsh. S. G., Amsricon Scientist, 49.202 (1961). (21) ~ ~A,. '.The~Genesis ~of Quentum n Theory." , M.I.T. Press. Cambrids. Mass..

,"-, "L--.".

"-. ". s

F Vital ~ F~~~ ~ to Structural F~rmulan." Houahton Mifnin Ca., Boaton. 1964. pp. 1067. (23) Gerherdt. C. F.. J liirprakt. Chrrnis, 27.439 (1842). (24) Freund. I.. "The Study of Chemical Compdtion? Dover Publiestions Inc., 1968, p. 624.

(22,i

0. T.., " ~~

~

Harold Goldwhite California State University Los Angeles. 90032

Volume 52, Number 10, October 1975 / 649