October 17, 1912] 



NATURE 



literature, inasmuch as it deals with the general 

 physiology • and functions of micro-organisms. 

 While appealing more particularly to the specialist, 

 the general reader who has some biological train- 

 ing and desires to obtain a general survey of the 

 activities of micro-organisms may peruse it with 

 advantage. The third chapter, which deals with 

 the form and structure of microbes, contains a 

 brief but sufficient account of recent work on these 

 'subjects, and the section on reproduction and 

 sexual reproduction of these lowly organisms is 

 particularly good. The chapters on infection, 

 immunity, and supersensitivation are models of 

 judicious selection from the voluminous literature, 

 and give excellent summaries of the subjects. 



The author, being a member of the staff of 

 the Pasteur Institute, naturally gives considerable 

 prominence to the views of the French school on 

 the physico-chemical nature of the toxin-antitoxin 

 reaction, but the other hypotheses are fully and 

 fairly stated. Final chapters deal with the 

 applications of bacteriology, vaccines, and curative 

 sera and chemio-therapy. We demur to the 

 statement (twice repeated) that because an 

 animal's serum may naturally possess some anti- 

 toxic power towards diphtheria or tetanus toxin, 

 such an animal must therefore ha\-e harboured the 

 diphtheria or tetanus bacillus. Though this may 

 be the explanation in some cases, we do not think 

 that it is necessary to postulate such an infection 

 in all instances. If antitoxin be generated during 

 artificial immunisation by the detachment of 

 natural side-chains from cell-protoplasm, there is 

 apparently no reason why similar side-chains 

 should not normally become detached by ordinary 

 physiological processes, constituting the small 

 amount of antitoxin sometimes found in a non- 

 immunised animal. 



We have read this book with much interest, 

 and can recommend it as giving an excellent 

 account of the subjects of which it treats. 



(3) As Mr. Golding says in the introduction to 

 this little book, " it has become an absolute neces- 

 sity that the dairy farmer should be acquainted 

 with some knowledge of the world of microscopic 

 beings with which he is beset on all sides, and be 

 able to distinguish his friends from his foes 

 among this host which he cannot see, but to which 

 he owes, and from which he fears, so much." 

 We think that this book will well supply this kind 

 of knowledge to the producer, the purveyor, and 

 the consumer of milk. After a simple introduc- 

 tory statement of what bacteria are and how they 

 grow and multiply, the use of starters for butter- 

 and cheese-making is considered. The production 

 of a pure milk is then discussed, and the sources 

 XO. 2242, VOL. go] 



and nature of contamination arc described, the 

 cow and milking, transit, distribution, and con- 

 sumption of milk all being considered. A few 

 pages are devoted to disease germs and the sour- 

 milk treatment, and the book concludes with a 

 short bibliography for the use of those who desire 

 further information on the subject. 



R. T. Hewlett. 



OUR BOOKSHELF. 



Nature Photography. What to Photograph, 

 Where to Search for Objects, How to Photo- 

 graph Them. By Stanley C. Johnson, M.A. 

 Pp. 115. (London: Hazell, Watson and 

 Viney, Ltd., 1912.) Price 15. net. 



" Nature " is a very wide term. It is not possible 

 to state concisely the meaning that the author 

 attaches to it. He does not refer to the larger 

 animals, and though he gets down to beetles and 

 butterflies, he does not include the smaller creatures 

 that are generally called microscopic. He deals 

 with fishes, birds, flowers, trees, reptiles and 

 some of the larger insects, giving what is evidently 

 his own experience in connection with the photo- 

 graphy of such things. This personal character 

 of the book gives it a value that a more inclusive 

 compilation might not possess. He has very little 

 to say about the actual photography, but treats 

 rather of the selection and arrangement of the 

 subjects, where and when to look for them, and 

 so on, and in this connection gives ad\'ice that 

 will be found of great value by those who do 

 work of this kind. 



In dealing with the bright colours and delicate 

 shades that some of these objects present, the 

 author's practice of using only stained plates 

 (" non-filter," as they are called) cannot be regarded 

 as thoroughly sound. His own illustrations of 

 coloured objects are not good, but it is possible 

 that the chief fault here lies with the maker of 

 the blocks. The truthful rendering of various 

 colours in monochrome is now fairly well under- 

 stood by those who care to study the matter, and 

 is not to be dismissed in a line or two by the simple 

 recommendation to use any particular plate. 



Dactylography, or the Study of Fins^er-prints. 

 By Henry Faulds. Pp. 127. (Halifax : Milner 

 and Company, n.d.) Price 15. net. 



This little book is the latest addition to the 

 "Twentieth Century Science Series," which in- 

 cludes volumes that treat scientific subjects in a 

 popular manner for the general reader. Mr. 

 Faulds here writes in an interesting way on a 

 subject with which his name has long been asso- 

 ciated as an authority, and the reader is provided 

 with a trustworthy account of the technique of 

 printing and scrutinising finger-patterns and of 

 classifying them. The practical results which 

 followed the study of finger-prints are enumerated, 

 and the future prospects of the subject outlined. 



