402 



NATURE 



[July 24, 1919 



editor of the Kolloid-Zeitschrift. Wolfg^ang 

 Ostwald possesses in no small degree the literary 

 facility of his father; and although this facility 

 leads sometimes to an over-wordiness of expres- 

 sion, the author has had considerable success 

 in directing the attention of wide circles of 

 workers to the importance of the study of 

 colloids. 



Although the third German edition, from which 

 the first English translation was made, was pub- 

 lished in 191 2, the translation was not published 

 until 1915. It will be understood, therefore, that 

 the publishers and translator were placed in a 

 position of some difficulty when they had to meet 

 the demand for a new edition of the English 

 version of the work. To issue merely a reprint 

 would have meant the continuance for sopie years 

 of a book which at the time of its first appearance 

 was already somewhat out of date ; and to obtain 

 a revision of the book by the author was impos- 

 sible owing to the existence of a state of war. A 

 compromise was therefore adopted, the co- 

 operation of Mr. E. Hatschek was obtained, and 

 an attempt was made to revise and bring up to 

 date the original translation. The translators 

 have sought to meet the situation " by leaving 

 entirely untouched those large portions of the 

 volume which contain the author's individual 

 views, to correct errors in quotation and in 

 mathematical formulae, and to add " (by the pen 

 of Mr. Hatschek) "numerous paragraphs intended 

 to bring to the reader various important advances 

 in colloid-chemistry which have been made since 

 191 2, especially such as have to do with the 

 mechanical properties of colloids, more particu- 

 larly their viscosity." The reviewer must confess 

 that he is not impressed by the success of the 

 attempted revision. 



It is to be regretted, in the first place, that the 

 translators have not indicated more clearly the 

 additions which have been made, but it would 

 appear, from such comparison with the first 

 edition as the reviewer has been able to carry out, 

 that the additions are confined, essentially, to two 

 sections on "Rate of Shear and Viscosity of 

 Emulsoids " and "Theory of Viscosity of Emul- 

 soids. " These two sections, by an active worker 

 in this domain, are valuable and have been satis- 

 factorily incorporated in the work. Sentences 

 have also been added here and there, but the 

 book, as a whole, can scarcely claim to be up to 

 date ; and it is to be regretted that the translators 

 did not seek more fully a way out of their diffi- 

 culties by more numerous footnote reference^ to 

 the recent literature. Apart from those in 

 the new sections added by Mr. Hatschek, the 

 reviewer has noticed only about half a dozen refer- 

 ences to literature published since the date of the 

 first edition. The translation has, in several par- 

 ticulars, been improved. "Dispersion medium," 

 for example, has been substituted for " dispersion 

 means," but it seems a pity to retain the expres- 

 sion "internal friction" for "viscosity," and a 

 still greater pity to make use of both terms in a 

 NO. 2595, VOL. 103] 



somewhat haphazard manner. " Molecular 

 kinetic " could, with advantage, be everywhere 

 substituted for "moleculo-kinetic, " and experi- 

 mental "results " would be more pleasing, to an 

 English ear at least, than experimental "find- 



Apart from the criticism which has been offered, 

 the book is a very useful one both for the specialist 

 student of colloids and for the large number of 

 workers in the various domains of science and 

 industry in which colloids are now recognised as 

 playing an important part. A survey of the more 

 important features of colloid-chemistry is here 

 presented in an interesting and readable, although 

 sometimes rather too diffuse, form ; and the book 

 furnishes a good introduction to a more detailed 

 and special study of the subject. The work does 

 not, however, claim to be exhaustive, and the 

 translators, by rendering "Grundriss " as "Hand- 

 book," give a somewhat false idea of the scope 

 of the book. A. F. 



PHYSIOLOGY FOR STUDENTS AND 

 PRACTITIONERS. 



A Text-hook of Physiology. By Dr. Martin Flack 

 and Dr. Leonard Hill. Pp. viii + 800. (London : 

 Edward Arnold, 1919.) Price 25^. net. 

 nPHE authors of this text-book deserve 

 -»■ hearty congratulations on having treated the 

 subject in a somewhat unorthodox way 

 which is decidedly interesting. Whether the work 

 will appeal to the rather whimsical tastes of the 

 medical student or teacher remains to be seen,, 

 since, on one hand, it may be regarded as 

 departing, in certain respects, too much from the 

 beaten track of examination requirements, and, 

 on the other, cannot by any means be 

 regarded as a cram-book for rapid revision. It 

 is, nevertheless, written expressly for the use of 

 medical students and practitioners, to the latter 

 of whom it should appeal strongly. 



The authors, as teachers of long experience and 

 wide repute, have a right to record their general 

 attitude to the subject in the form of a text-book, 

 but it is almost certain that many teachers will 

 disagree with them regarding the balance of the 

 various sections of the work, .\mong the best 

 features of the book are the clearness of the tables 

 and schemes, and the great wealth of illustrative 

 detail drawn from the most varied sources 

 (pp. 500, 633, 771, for instance). The chemical 

 parts are treated with brevity, and contain 

 some statements that will not be generally 

 accepted. Thus (p. 31) colloids are said to exert 

 no osmotic pressure ; again (p. 85), it is ques- 

 tioned whether amino-acids are normal constitu- 

 ents of blood plasma ; on p. 93 the chemistry of 

 formation of methaemoglobin is unorthodox. 



One of the most fully treated sections is that 

 dealing with the circulation ; there are, however, 

 some errors in this portion — for instance, in the 

 description of the heart-lung preparation and irt 



