4i 



NA TURE 



[September 23, 1922 



when confronted with the hieroglyphics of a sister 

 science." The present reviewer is unable to agree 

 that the " jargon " here employed is likely to promote 

 clear thinking, and does not believe that it will ever 

 form the basis of a common language among all who 

 are interested in the subject. 



Handbook fur Field Geologists. By Dr. C. W. Hayes. 

 Third edition, revised and enlarged by Sidney 

 Paige. Pp. xi + 166. (New York: J. Wiley and 

 Sons, 1 111 -. : London : Chapman and Hall, Ltd, 1921.) 

 i$s. <></. net. 

 Dr. Hayes's manual, well bound, with rounded corners 

 and gilt edges, is clearly intended for the pocket or the 

 haversack. It is based on the methods adopted by the 

 United States Geological Survey, and covers a certain 

 amount of simple topographic surveying for ascertain- 

 ing correct positions. The diagrams to" illustrate forms 

 of outcrop are small, as is necessitated by the size of the 

 page, and we may prefer the bolder treatment given to 

 this subject in Dr. Elles's recently published " Study of 

 Geological .Maps." Some matters, such as the descrip- 

 tion of common minerals in Appendix I., with its old- 

 fashioned chemical formula;, might have been left to 

 the text-books with which the surveyor must become 

 acquainted before he goes into the field. The directions 

 as to the collection of the remains of fossil vertebrates 

 and the investigation of placer deposits will rouse feel- 

 ings of envy among those whose work is confined to the 

 British Isles. But is the work of a geologist ever so 

 confined ? For those who are true geologists because 

 they travel, Mr. Paige has provided a compact and 

 handy guide. It points out, at any rate, on what details 

 attention should be fixed. G. A. J. C. 



The Psychology oj Medicine. By Dr. T. W. Mitchell. 



Pp. viii + 187. (London: Methuen and Co., Ltd., 



1921.) 6s. net. 

 This book is intended primarily for those who, without 

 being students of medicine or psychology, wish to keep 

 themselves abreast of modern thought in these subjects. 

 The earlier chapters are devoted to a discussion of the 

 various psychological theories, commencing with Janet's 

 theory of dissociation and its connexion with hysteria 

 and the hypnotic state, and then passing on to Freud's 

 theory of repression. The rest of the book deals with 

 the conception of the unconscious, with psycho-analysis, 

 and with the classification, treatment, and prevention of 

 neuroses. Psycho-analysis is described from three 

 aspects, namely, as a method of investigation, as a 

 doctrine of the content and process of the mind, and 

 as a therapeutic method. 



The clearness and impartiality with which Dr. 

 Mitchell has considered conflicting views will be appre- 

 ciated by the reader who requires only a general outline 

 of modern psychology. A few notes are appended for 

 guidance in selecting literature for further study of the 

 subject. 



Graphical Analysis : A Text-book on Graphic Statics. 



By W. S. Wolfe. Pp. xiv + 374. (Xew York and 



London : McGraw-Hill Book Co., Inc., 1921.) 20s. 



net. 



Mr. Wolfe offers us a detailed study of the graphical 



methods as used in statical problems, with applications 



to tin investigation of various types of structures. He 



NO. 2760, VOL. I io] 



first sets out the ordinary theory of force and funicular 

 polygons. The graphical processes for finding centres 

 of gravity, moments, and moments of inertia come 

 next, and then bending moments and shearing stresses 

 of beams. Frameworks follow, applied to all kinds of 

 trusses, roofs, and arches. After a chapter on moving 

 loads on bridges we get the study of masonry piers 

 and masonry arches as well as of reinforced concrete. A 

 chapter on design of beams and struts, and a chapter on 

 miscellaneous problems, complete an exhaustive account 

 of a most important subject. There are more than 

 700 diagrams, all very well drawn and reproduced. It 

 is difficult to see what advantage there can be in using 

 A-B to designate the line AB, or A-B-C to designate 

 the angle ABC. In view of the alarming increase in 

 the prices lately charged for scientific books, it is a 

 pleasure to note the excellent get-up of Mr. Wolfe's 

 book and its moderate price. S. B. 



The Horninian Museum : A Handbook to the Collections 

 illustrating a Survey of the Animal Kingdom. By 

 H. N. Milligan. Second edition. Pp. 66. (London 

 County Council, 1922.) 6d. 

 This is really an elementary account of the animal 

 kingdom on the usual lines of descriptive zoology. It 

 does not seem to refer definitely to any particular 

 specimens placed on exhibition ; but no doubt most of 

 the forms mentioned are on view in the museum cases 

 and serve instead of drawings. The statements are 

 generally accurate and as precise as brevity permits. 

 The style is clear, but assumes some familiarity with 

 words not in the vocabulary of the general visitor, such 

 as " retractile," " aberrant," " everted." If the class 

 Myriapoda is retained, this is merely an instance of the 

 " conservative attitude found convenient in a hand- 

 book to be used by the general public." To say that 

 norvegicus and rattus are " specific names " is but to 

 share a common error, and if the phrase " the Thero- 

 morpha contains " is a grammatical howler, it is the 

 only one of its kind in this book. Mr. Milligan has 

 accomplished a difficult task with much success. 



Radioactivity and Radioactive Substances. By Dr. J. 

 Chadwick. (Pitman's Technical Primer Series.) 

 Pp. xii+m. (London: Sir Isaac Pitman and 

 Sons, Ltd., 1921.) 2S. 6d. net. 

 Sir Ernest Rutherford's words of commendation 

 in the Foreword to this little book are well deserved. 

 ''It is a clear and accurate account of radioactive 

 phenomena written by one who has a first-hand know- 

 ledge of the facts." " To all those who are interested 

 in the development of our knowledge of this fascinating 

 subject I can strongly recommend this book as a simple, 

 concise, and accurate statement of the main facts 

 and theories." The diagrams are numerous, and, 

 though on a small scale, are remarkably clear. Similar 

 volumes on other branches of modern physics would 

 be welcome. 



The Rural Community. By Llewellyn MacGarr. Pp. 

 xv + 239. (Xew York : The Macmillan Co. ; London : 

 Macmillan and Co., Ltd., 1922.) 85. net. 

 This book deals in a very elementary fashion with the 

 social and economic factors affecting the agricultural 

 worker, and its chief merit is its extreme simplicity. 



