586 



SCIENCE. 



LN. S. Vol. XV. No. 380. 



ing branches. The reviewer rmist confess his 

 inability to understand clearly Professor Lock- 

 yer's differentiation between descending and 

 ascending stars, although not wishing to ques- 

 tion the probability that both branches exist. 



In subsequent chapters the author interest- 

 ingly discusses the bearing upon the dissocia- 

 tion hypothesis of the recent discoveries of 

 series in the spectra of the elements, of pres- 

 sure shifts of lines, of magnetic perturbations 

 (Zeeman effects), and of the 'fractionation' 

 evidence. He finds in them a quite satisfactory 

 confirmation of his hypothesis, and displays 

 great skill and command of the subject in 

 marshaling to its support the data from such 

 various sources. 



As has been said of other volumes in this 

 series, the illustrations do not adequately 

 reproduce the author's original photographs, 

 and could be greatly improved upon in a future 

 edition. Edwin B. Frost. 



Outlines of Electrochemistry . By Harry C. 

 Jones, Associate Professor of Physical 

 Chemistry in the Johns Hopkins Univer- 

 sity. New York, The Electrical Review 

 ■ Publishing Co. Price, $1.50. 



The author has not tried to give an exhaust- 

 ive account of electrochemistry, for he pre- 

 pared the seven chapters, which cover about 

 one hundred pages, for a technical journal, 

 whose readers are for the most part men busy 

 in every field of applied engineering science; 

 consequently he wisely selected those theoretic- 

 al topics which would appeal most strongly 

 to this particular class of students. The book, 

 however, will prove instructive and helpful to 

 all who wish to get a clear and definite knowl- 

 edge of the subjects it presents. The writer 

 has read it with profit, and feels sure that he 

 does not err in reconnnending it. One might, 

 however, well ask whether 'the whole subject 

 of the electrolytic separation of the metals 

 was opened up' (p. 44) through the study of 

 the decomposition values of the ions by Le- 

 Blanc, Freudenberg and others in Ostwald's 

 laboratory, when it is recalled that all but 

 three or four of the separations recorded by 

 these chemists had been made long before by 

 others? Or, if 'the decomposition values of 



the ions' is the vital point, should we omit 

 mention of the work of Kiliani, who first car- 

 ried out metal separations by attention to the 

 differences in electromotive force? Perhaps 

 these may be regarded as minor matters, but 

 the historical development of the subject calls 

 for their presence. 



EoGiUi F. Smith. 



Enzymes and Their Application. By Dr. Jean 

 Effbont. Vol. I., The Enzymes of the Car- 

 bohydrates. Translated by Samuel C. 

 Prescott. New York, John Wiley & Sons; 

 liondon. Chapman & Hall, Limited. 1902. 

 8vo. Pp. 322. 



This is a very excellent work and is a valu- 

 able addition to the literature on enzymes and 

 their application. The book is designed to 

 meet the wants of not only scientific investi- 

 gators, but also of those interested in the in- 

 dustrial application of these substances, and 

 will be appreciated by both classes. The au- 

 thor has carried out his purpose in a clear, 

 concise manner. From the standpoint of 

 theoretical consideration he is careful and 

 conservative, and his treatment of the tech- 

 nical apijlication of- enzymes to commercial 

 practices is unusually full and clear for a 

 work of this kind. The book is more than a 

 compilation, inasmuch as the author has, as 

 stated in the preface and borne out by inter- 

 nal evidence, confirmed in his laboratory most 

 of the facts presented. The second volume 

 which is now in course of preparation, will 

 take up the proteolytic enzymes and the tox-- 

 ins, and its appearance will be looked for with 

 interest. Professor Prescott is to be congrat- 

 ulated in presenting a translation that in no 

 way detracts from the original. The printing 

 is well done and the paper and binding good. 

 Albert I'. Woods. 

 Bureau of Plant Industry, 



U. S. Department of Agriculture, 

 Washington, D. C. 



Animals of the Past. By Frederic A. Lucas. 



New York, McOlure, Phillips & Co. 1901. 



One who has had much to do with a public 

 museum of extinct vertebrates is pretty sure of 

 the queries that the ordinary sight-seer will 



