February 7, 1901] 



NATURE 



151 



We are also indebted to Hermite for the first proof 

 that e, the base of the Napierian logarithms, is transcen- 

 dental, a result which paved the way for Lindemann's 

 proof that the same is true of tt. 



In 1862 Hermite was elected to a newly founded chair 

 at the Ecole Nprmale, and later on he also became pro- 

 fessor at the Ecole Polytechnique and the Sorbonne. 

 Instead of continuing to teach on the old lines which 

 he found still in vogue, Hermite introduced into his 

 lectures the great discoveries of Gauss, Abel, Jacobi 

 and Cauchy. He thus founded for France a new school 

 of higher geometry, and the large number of mathe- 

 maticians of distinction who have studied under him bear 

 abundant testimony to the success of his innovation. 



During the later period of his life Hermite appears 

 to have directed his attention more especially to ques- 

 tions connected with the calculus. In conjunction Vith 

 Darboux and Jordan, he presented the general theory of 

 linear differential equations in an entirely new light, 

 choosing the algebraic rather than the geometric method 

 of presentation. His work on Lame's equation leads to 

 the solution of a large number of problems in applied 

 mathematics. 



The " Cours de M. Hermite" constitutes an important 

 work on the theory of functions. 



About eleven years ago Hermite delivered an inau^ral 

 address before the President of the French Republic, 

 which was published in the Bulletin des Sciences )>iath^- 

 matiques for January 1890. In 1892 he celebrated his 

 jubilee, and it is remarkable that the same year wit- 

 nessed also the jubilee of Pasteur. The new century 

 and the new era in history which has come upon our 

 country will both be the poorer for the loss of M. Hermite, 

 but his works will be handed down to posterity. 



An account of his work has been given in the Cotnptes 

 rendus for January 21 by M. C. Jordan, himself the 

 author of important papers on the fields of study which 

 Hermite had chosen to work in. To this account we are 

 indebted for much matter contained in the present notice, 

 and we are glad that M. Jordan pleads for the publication 

 of Hermite's collected works. Many of his ideas are 

 scattered in journals or letters that are difficult of access, 

 and it will be of inestimable use to mathematicians to 

 have them printed in book form. G. H. B. 



ADO LP HE CHATIN. 



A DO LP HE CHATIN died on January 13 at the age 

 ■^~*- of eighty-seven. He was a native of Dauphine, 

 and was born at Ile-Marianne de-Saint-Quentin, near 

 Tullins, "d'une famille peu fortunee," according to M. 

 Gaston Bonnier, from whose eloge in the Comptes rendus 

 of the Paris Academy (January 21) some of the following 

 facts of his life-history are taken. He received his early 

 education at Tullins, and at seventeen joined an apothe- 

 cary at Saint- Marcellin. Three years later (1833) he 

 went to Paris under an apothecary named Briant, who, 

 recognising his pupil's capabilities, urged him to study 

 pure science as well as pharmacy. Chatin, who always 

 gratefully remembered his good friend's advice and 

 encouragement, worked to such effect that he took 

 bachelors degrees both in Letters and Science, and six 

 years after his arrival in Paris obtained the degree of 

 Doctor of Science. In the next year, 1840, he read his 

 thesis before the School of Pharmacy, and was duly 

 admitted. The somewhat ambitious title of this thesis, 

 " The Comparative Anatomy of Plants applied to Classi- 

 fication," indicated the line of work in which he has done 

 most service to botany. It was a short paper dealing 

 with the occurrence, structure and general properties of 

 albumen in plant-seeds. He took the view that the 

 presence of endosperm in the seeds, implying a temporary 

 arrest in the embryogeny of the plant, indicates a lower 

 condition than that existing in the exalbuminous seed. 



NO. 1632, VOL. 63] 



" From this time," he tells us in the introduction to the 

 " Anatomie Compar^e des Vegetaux," " comparative 

 anatomy was (with plant symmetry) the principal object 

 of my labours." 



In 1844 he took the degree of Doctor of Medicine, and 

 in 1848 was elected to the chair of Botany at the School 

 of Pharmacy, his chief competitor being M. Payer. 

 Twenty-five years later he became Director of the 

 School, retiring in 1886 with the title of Honorary 

 Director. In 1874 he was chosen a member of the 

 Academy of Science, succeeding Claude Gay, and ii> 

 1897 became President of the Academy. He was also a 

 member of the Academy of Medicine, and filled various 

 other posts of honour. 



His first memoir, published in 1837, was on the 

 symmetry of structure of plant organs, and sixty years 

 later appeared the last part of his studies on the 

 symmetry of the vascular bundles of the petiole. His 

 best-known work is the "Anatomie Comparee" (1856- 

 1862), which was never completed. It consists of two 

 parts, the larger illustrated by 113 plates, on Dicotyle- 

 donous Parasites, the smaller with 20 plates, on Aquatic 

 Monocotyledons. It is difficult to estimate the value of 

 this work. Its chief worth lies in the beautifully executed 

 figures illustrating the anatomy of the stem, leaf and root 

 of a large number of genera and species. Their prepar- 

 ation implies considerable skill and much hard, con- 

 scientious labour, with which the results, as embodied in 

 the text of the book, are scarcely commensurate. But it 

 is hard to judge the work of forty years ago from our 

 present standpoint, and in helping to revive the study of 

 plant-anatomy, which had fallen into neglect, Chatin did 

 good service, and might well, in his later years, regard 

 with some complaisance and pride its present important 

 position as one of the factors in the evolution of a 

 natural system of plant-classification. 



Chatin also studied the organogeny of the flower, 

 especially of the androecium, and collected the results of 

 numerous small papers, which had previously appeared 

 in the Comptes rendus and elsewhere, in a volume 

 entitled " De I'Anthere " (i87o)--a comparative account 

 of the development, structure and mode of dehiscence of 

 the anther in a number of families and genera. His 

 memoir on the life-history and structure of Vallisneria 

 spiralis is a useful piece of work, illustrated with charac- 

 teristic elaborate detail. But he by no means restricted 

 himself to the study of the symmetry and anatomy of 

 plants ; the subjects of his published works and papers 

 comprise the results of chemical as well as botanical 

 investigations. Among his earlier papers were several 

 dealing with the occurrence of iodine in air and water, 

 its presence in plant tissues and its effect on plant 

 growth. He also wrote on the potato disease, the vine 

 disease, and on the cultivation of truffles and other 

 edible fungi, and published a small book on watercress. 



For the past two years his health, hitherto robust, had 

 been gradually failing, and his last days were spent in 

 retirement at his country home at Essarts-le-Roi, near 

 Rambouillet. His son, M. Joannes Chatin, a professor at 

 the Sorbonne and a member of the Academy, has made a 

 few contributions to botanical literature, but his work has 

 been chiefly in other branches of science. 



NOTES. 

 Arrangements are being made by the Royal Academy of 

 Sciences of Sweden to celebrate the third centenary of the death 

 of Tycho Brahe, the founder of modern practical astronomy, on 

 October 24, 1901, by a special meeting. It is also proposed to 

 further commemorate Tycho's work by the publication of a 

 facsimile of the original edition of his celebrated " Astronomise 

 instauratse mechanica," a perfect copy of which is in the library 

 of the Academy. It is well-known that when at Wandesburg 



