34 



NA rURE 



[May 12, 1904 



likewise seeks to import into the general process of 

 chemical action the conceptions of dynamics. The 

 simple words with which he concludes his paper sound 

 somewhat archaic to-day, but fifty-four years ago they 

 must have startled the members of Section B. " In 

 using the atomic theory, chemists have added to it of 

 late years an unsafe, and as 1 think, an unwarrant- 

 able hypothesis, namely that the atoms are in a state 

 of rest. Now this hypothesis I discard, and reason 

 upon the broader basis of atomic motion." 



Williamson was not a prolific writer, and his fame 

 mainly rests upon his work of this period and upon 

 what he achieved during the first ten years of his pro- 

 fessorial activity. He published comparatively little 

 between 1S54 and 1864, but under the stimulus of 

 the new movement, he took an active part in the formu- 

 lation of what is still current doctrine, and produced a 

 series of papers on the principles of chemical classifica- 

 tion, valency, and nomenclature which e.xercised a 

 powerful influence on chemical -teaching in this 

 country. 



Williamson was elected into the Royal Society in 

 1855, and served on the council from 1859 to 1861, again 

 from 1869 to 1871, and for a third time from 1873 to 

 1890, during which period he acted, as already stated, 

 as foreign secretary. In 1889-1890 he was made a 

 vice-president. In 1862 he received a Royal medal. 

 He was twice president of the Chemical Society— viz., 

 m 1863-65 and again in 1869-71, and was one of the 

 SIX presidents who had been fellows of the Society for 

 upwards of half a century who were present at the 

 memorable banquet in 1898. He was largely instru- 

 mental m establishing the present series of abstracts of 

 foreign chemical literature which form so valuable a 

 feature of the journal of the Chemical Society. 



u- ''^"•^ '^^ ^^'^* president of the British Association. 



His merits as a man of science received wide-spread 

 recognition. He was an honorary graduate of Dublin 

 tdinburgh, and Durham, a member of the Institute 

 ot France and of the Berlin Academy, and of many 

 scientific societies on the Continent and in America. 



T. E. Thorpe. 



EUILE DUCLAUX. 

 J N the death of Emile Duclaux science has lost one of 

 her most devoted and brilliant workers. His 

 career has formed the principal link between the bac- 

 teriology of the present day. and what may be called 

 the heroic period in the history of micro-biol'ogy which 

 .ollowed on the unveiling, by'the genius of Pasteur, of 

 the secret of fermentation, and the consequent opening 

 out of avenues through which innumerable problems 

 could be successfully attacked. 



The Pasteur Institute will in particular mourn its 

 loss, for, owing to the charm of his personality and the 

 extraordinary catholicity of his scientific enthusiasms 

 he was a worthy successor to the great leader, and the 

 continuance of that brotherliness which was such a 

 striking feature among the little community of scientific 

 mvestigators in the Rue Dutot must in "considerable 

 measure be attributed to his influence. 



Duclaux was born at Aurillac, on June 24, 1840. 

 He was not a son of fortune, and it was only by dint 

 of hard struggle and a determination wliich was 

 capable of much self-denial that he succeeded in beom- 

 ing a Normalien in 1859. At the Ecole Normale he 

 studied principally chemistry and physics, and left the 

 school as Agrege in 1862. 



At that time Pasteur, who had returned to the Ecole 

 Normale as director of scientific studies, had recently 

 established the positions of Agreges preparateurs, 

 NO. 1802, VOL. 70] 



whereby an able and earnest young graduate might re- 

 main for a few years as a research-assistant to one of 

 his masters. 



For some three years Duclaux remained preparateur 

 to Pasteur, and was his first lieutenant during the 

 celebrated investigations into the causes of diseases in 

 wine and into the silkworm disease, which had nearly 

 ruined some of the Departments of France. 



In 1865 he became Docteur es Sciences, presenting a 

 thesis upon fractional distillation. In the same year 

 he was appointed a professor at the lycde in Tours, and 

 during the following year became acting professor of 

 chemistry at Clermont. It was at Clermont that 

 Pasteur stayed with Duclaux during the troublous times 

 of the war, and it was here that the intimacy and affec- 

 tion which ceased only at the death of Pasteur was 

 established between them. It was at Clermont, also, 

 that he numbered among his students Roux, whom he 

 introduced to Pasteur. 



From Clermont, Duclaux went to Lyons as professor 

 of physics, where he remained until he accepted, in 

 1878, the chair of physics and meteorology at the 

 Institute Agronomique in Paris. In 1886 he became 

 professor of biological chemistry at the Sorbonne, which 

 position he held until his death. When the Pasteur 

 Institute was completed, he transferred his classes to 

 the Rue Dutot. At the death of Pasteur, Duclaux was 

 elected to succeed him as director, and for the last nine 

 years the great work of the Institute has been developed 

 under his guidance. He, however, has not taken any 

 direct part in that portion of its activities dealing with 

 infective diseases, but has confined himself more par- 

 ticularly to the chemical and industrial side of micro- 

 biology. 



\\'hen one considers the scientific work of Duclau.x, 

 the first and most striking point is the wide range of 

 subjects it includes. Trained as a chemist and physicist, 

 he has occupied chairs in both these subjects, and has 

 published a not inconsiderable number of original re- 

 searches in the domains of pure chemistry and physics. 

 At the same time his most important work was bio- 

 logical. Like Pasteur, he was a chemist who worked at 

 biology, but principally at that department of biology 

 dealing with the physiology of micro-organisms and the 

 chemistry of enzymes, and he brought his training in 

 the exact sciences to bear upon investigations of a bio- 

 logical character, with the greatest success. 



The list of his original contributions to scientific 

 journals contains upwards of eighty papers, and in- 

 cludes papers on molecular physics, chemistry, meteor- 

 ology, physiology of digestion, enzymes, vegetable 

 physiology, bacteriology, and technological papers on 

 milk, butter, wine, sericulture ; and he is also the author 

 of several books. In " Ferments et Maladie " and " Le 

 Microbe et la iVIaladie " he gave popular expositions of 

 the results achieved by the Pasteurian method, and the 

 complete change thereby produced in the standpoint 

 from which infectious diseases were regarded. 



In 1896, Duclaux published his " Pasteur, Histoire 

 d'un Esprit," which deals with the researches of the 

 great master from first to last, pointing out the con- 

 dition of knowledge on the various subjects before 

 Pasteur had brought them, one by one, under the in- 

 fluence of his imagination and accurate experimenta- 

 tion. This forms one of the most brilliant descriptions 

 of the operation of scientific method in unravelling the 

 relationship of phenomena ; its perusal might well form 

 a portion of the education of every student of science. 



The most important of Duclaux's published books is 

 the " Traite de Microbiologic " — the four volumes of 

 which appeared during the years 1S98 to 1901 — each 

 chapter of which bears the stamp of the author's indi- 

 viduality, and contains many original observations not 



