lOO 



NATURE 



[June 2, 1898 



model, and one could wish, in addition to the figures, for 

 diagrams of models to be made in folded paper. 



One purely external fact may be noted about the 

 book : unlike most foreign publications, it can be bought 

 neatly bound in buckram. 



W. H . AND G. Chisholm Young. 



MODERN DEVELOPMENT OF THE ATOMIC 

 THEOR V. 



The Arrangement of Atoms in Space. By J. H. Van 't 

 Hoff. Second revised and enlarged edition, with a 

 preface by Johannes Wislicenus, &c. ; translated and 

 edited by Arnold Eiloart. Pp. xi + 211. (London: 

 Longmans, Green, and Co., 1898.) 



THE history of the development of that department 

 of science which it is now usual to call stereo- 

 chemistry is extremely interesting. While it shows that 

 great results often spring from small beginnings, it also 

 shows that ahhough genius may discern in apparently 

 trivial phenomena the basis of very far-reaching ideas, it 

 requires the united efforts of a large number of workers 

 both to extend the applications of the idea and to render 

 its foundation firm and secure. In 1848 Pasteur dis- 

 covered that racemic acid, itself possessing no action on 

 a ray of polarised light, is resolvable into two acids, each 

 of which rotates the plane of polarisation in equal but 

 opposite directions, and that this property of optical 

 activity is associated with hemihedrism in the crystalline 

 form. Not till more than a quarter of a century later, 

 namely in September 1874, did Van 't Hoff give to the 

 world his ideas on the representation of chemical struc- 

 ture in space. Two months afterwards similar views 

 were put forward by Le Bel. So far as it obtained any 

 notice at all, the new theory was received chiefly with 

 ridicule. It is now accepted by the whole chemical 

 world. 



Nearly all the difficulties attending the new doctrine 

 were cleared away in Van 't Hoff's " Dix Anndes dans 

 I'histoire d'une theorie" (1887), and since that time a new 

 chemical literature has sprung up devoted to the ex- 

 position of the doctrine and its application to the large 

 number of examples now known. This little book will 

 be useful to students looking at the subject from the 

 theoretical point of view. And perhaps it supplies all 

 that is really desirable, inasmuch as it provides freely 

 references to the original papers of the numerous chemists 

 who have worked experimentally upon the subject ; and 

 so, perhaps, the lack of detail as to methods is less 

 likely to be felt. Dr. Eiloart, the translator of the 

 volume, is known as an investigator of stereo-chemical 

 problems, and he has published a useful " Guide to Stereo- 

 chemistry," based on lectures delivered by him a few 

 years ago in the Cornell University. The translation 

 may be therefore trusted to represent accurately the 

 views and intention of the author. The worst that can 

 be said is that the exposition is in some places rather 

 scanty, as, for example, in all that relates to the supposed 

 configuration of the nitrogen atom, no alternative views 

 being considered. There is an interesting appendix, 

 containing a note by Prof. A. Werner, of Zurich, on the 

 NO. 1492, VOL. 58] 



application of stereo-chemical ideas to the isomerism of 

 metallic compounds, more especially to the plato- 

 ammines and cobalt-ammines. The configuration of 

 the groups MAg, in which M is the metal and A the 

 group NH3or some negative radicle, is represented by 

 a regular octahedron, the metal occupying the centre, 

 and the groups having their places at the solid angles. 

 This accounts for the existence of two isomeric forms of 

 these compounds, but the reader is left to find out for 

 himself in what manner the ionisable radicles which 

 enter into the composition of the saks are attached to 

 this octahedral arrangement. It is interesting to find 

 that the possibility of applying stereo-chemical ideas to 

 elements other than carbon and nitrogen is at last 

 beginning to be recognised by chemists. W. A. T. 



OUR BOOK SHELF. 



The Litiacre Reports. Vol. iii. 1895- 1897. Edited by 



E. Ray Lankester, M.A. (London : Adlard.) 

 This volume contains eighteen papers published by 

 Prof. Lankester and his staff at Oxford since the summer 

 of 1895, together with the reports of the teaching in the 

 department over which he presides, and a list of the 

 zoological additions to the Museum during the past two 

 years. 



As a record of work done in the laboratory at Oxford 

 it compares favourably with the two volumes which pre- 

 ceded it, and proves that the energy and perseverance 

 in research of the Oxford zoologists still form one of the 

 most gratifying features of the science schools of that 

 University. Although one-half of the papers in the 

 volume deal with the morphology of segmented worms, 

 the others treat of animals in widely separated classes, 

 showing that under the guiding influence of Prof. 

 Lankester the school is not likely to suffer from the spirit 

 of hasty generalisation on the one hand, nor from the 

 evils of narrow-minded specialisation on the other. 



Two papers by Mr. Goodrich on the Coelom theory 

 and on the homologies of the Annelid prostomium can 

 be compared with Prof. Benham's papers on certain 

 Earthworms. The former may be taken as admirable 

 examples of biological reasoning and clear statements of 

 views, the latter as examples of laborious and valuable 

 investigations of anatomical details. Prof. Lankester 

 may be heartily congratulated upon this further proof of 

 the stimulating influence of his teaching, and upon the 

 skill and zeal of his friends and pupils at Oxford. 



S. I. H. 



Anatomia Ve^etale. By Dr. F. Tognini. Pp. 274 



(Milan: U. Hoepli, 1897.) 

 Fisiologia Vegetale. By Dr. L. Montemartini. Pp. 230. 



(Milan: U. Hoepli, 1898.) 



These two handy little manuals are both apparently 

 largely based on the " Lehrbuch der Botanik " by Stras- 

 burger, Noll, Schenck and Schimper. The vegetable 

 anatomy, by the late Dr. Tognini, is a good account of 

 the leading features of the science. More attention is 

 devoted in it to the histology of plants than to their 

 gross anatomy. The small size of the book necessitates 

 a sketchy treatment of the subject, and the descriptions 

 in several instances are meagre. Thus the structure and 

 arrangement of the bast is dismissed in a few words, 

 while scarcely anything at all is said of the changes 

 which take place in the sieve-plates. However, much 

 accurate information is contained in the book, and a 

 great deal of the results of recent investigations are 



