i88 



NATURE 



[October 17, 1912 



ject. And, after all, it is for this latter class that 

 such books are primarily intended. But in the 

 present case there is scarcely room for doubt that 

 Prof. Soddy has successfully accomplished the 

 very difficult task of making physics of absorb- 

 ing interest on popular lines. This has been done 

 without any of that sacrifice of exactness of 

 statement which so often mars works of this 

 kind ; thus the trained physicist and the novice 

 may read the book with equal pleasure. It is 

 quite surprising how many phenomena the author 

 has been able to deal with in this fashion, and 

 what up-to date work he has been able to intro- 

 duce. There is no space available to detail the 

 various contents more than to say that such sub- 

 jects as the kinetic theory of matter (including 

 reference to Perrin's beautiful experiments on 

 Brownian movements} and radioactivity, among 

 others, are treated with admirable lucidity. A 

 book of this kind deserves a longer review ; it is 

 to be hoped it will have a large circulation, for 

 it forms a worthy addition to the excellent series 

 to which it belongs. 



(2) This consists of a series of descriptions of 

 experiments which Prof. Burch has compiled, 

 based upon the work of practical classes in the 

 Physiological Laboratory, Oxford. About sixty 

 experiments are described, dealing with the 

 dioptrics of the eye, judgments of the eye, sensa- 

 tions of the eye, the measurement of colour sensa- 

 tions, and experiments with flashing light. 



(3) From time to time during the progress of 

 physical science a book appears the author of 

 which is thoroughly dissatisfied with everything 

 that has been accomplished, and desires to begin 

 again on an entirely new foundation. This book 

 is the latest of the kind. The author, in this case, 

 claims to have m.ade an intimate study of natural 

 phenomena, and to possess a lengthened experi- 

 ence in physical research. Such a claim is, how- 

 ever, scarcely borne out by a perusal of his book. 

 One cannot help thinking that his dissatisfaction 

 with things in general arises rather from his own 

 lack of acquaintance with the exact nature of 

 physical science than from any fundamental error 

 in present-day theories. It is really impossible to 

 take the book seriously ; at any rate, the present 

 writer finds it so. 



(4) This is a little book dealing with various 

 applications of the kinematograph to scientific 

 research. The author directs attention to what 

 has already been achieved, and throws out sug- 

 gestions as to the lines upon which further pro- 

 gress could be made. 



(5) This is a treatise of a ratlier advanced char- 

 acter, though very much compressed, upon wave- 

 motion, &c. , particularly in its applications to 



NO. 2242, VOL. 90] 



sound and light. It is rather poorly printed, and 

 the diagrams are not well produced. 



(6) Like many similar German text-books of 

 physics, the treatment in this one is very full — 

 surprisingly so when it is remembered that it is 

 intended for use in schools. This is the first 

 volume, and comprises mechanics, heat, and 

 sound. The type and diagrams are good. 



MICRO-ORGANISMS AND THE 

 HOMESTEAD. 



(i) Microbiology for Agricultural and Domestic 

 Science Students. Edited by Prof. C. E. 

 Marshall. Pp. xxi + 724. (London: J. and A. 

 Churchill, 1912.) Price 105. 6d. net. 



(2) Microbes and Toxins. By Dr. E. Burnet. 

 With a preface by Elie Metchnikoff. Translated 

 from the French by Dr. C. Broquet and Dr. 

 W. M. Scott. Pp. xvi + 316. (London: 

 William Heinemann, 1912.) Price 5s. net. 



(3) Bacteria as Friends and Foes of the Dairy 

 Farmer. By Wilfrid Sadler. Pp. xv+112. 

 (London: Methuen and Co., Ltd., 1912.) Price 

 IS. 6d. 



(i) ]\ /T ICRO-ORGANISMS are of far-reaching 

 IVi importance in agriculture, and the 

 domestic science student cannot afford to neglect 

 them, and the appearance of a work dealing with 

 these branches of bacteriology, particularly the 

 latter, is therefore opportune. 



A number of well-known authors, specialists for 

 the most part in their various subjects, have col- 

 laborated to produce the book under review. The 

 editor. Prof. Marshall, fully recognises the weak- 

 ness of this system of compilation, and has 

 attempted, with success we think, to coordinate 

 the whole. He points out that the term "bac- 

 teriology " has come to include many groups of 

 micro-organisms other than the true bacteria, and 

 the term " microbiology " has therefore been 

 employed as a title for the present book. 



The scheme of the book is comprehensive and 

 well conceived, and ranges over a wide field. The 

 subject-matter is divided into three parts : the 

 first deals with the morphology and culture of 

 micro-organisms, including the Protozoa; the 

 second with the physiology of micro-organisms,- 

 and the third with applied microbiology. The las! 

 includes sections on air, water and sewage, tht 

 soil, milk and milk products, the preservation ot 

 foods, alcohol, vinegar and other fermentation 

 products, and the microbial diseases of plants, 

 man, and animals. We have found practically 

 nothing in the contents to criticise, and the book 

 is well illustrated with 128 figures in the text and 

 one coloured plate of the inalaria parasite. 



(2) This book fills a lacuna in bacteriological 



