February i8, 19 15] 



NATURE 



669 



of geographical, and especially climatic, control 

 over the distribution of products and the activities 

 of man in making- use of them. Thus, the 

 regional division of the world according to 

 climate and vegetation is only briefly, and not 

 completely, referred to. It may be that some 

 geographers have made climatic control a sort 

 of fetish ; it should not be that, but it deserves a 

 very important place in the study of commercial 

 geography, and calls for precise expression — as 

 an illustration of this necessity it may be sug- 

 gested that the statement in the present work tha*: 

 in .Australia *' wheat is gr^iwn up to the 20-in. 

 line of rainfall " misses the real point of the 

 conditions of rainfall which determine the wheat- 

 growing area there. It should be noticed that 

 Mr. .\lford Smith inserts tables of statistics, 

 wisely averaged, and among them details at con- 

 siderable length of several large ports of the 

 United Kingdom. 



Atlas of Japanese J'egetation, with Explanatory 

 Text.' Edited by Prof. M. Miyoshi. (Set xv., 

 102-107.) (Tokyo : Maruzen Company, Ltd. ; 

 London : W. Wesley and Son, 1914-) n.d. 

 This continuation of Prof. Miyoshi's well-known 

 atlas includes six beautiful collotype plates from 

 photographs of the vegetation of the luxuriant 

 mountain forests in the province of Shinano. 

 Nothing could convey a better idea of the wonder- 

 fully varied plant communities of Japan than this 

 carefully selected series of photographs with the 

 accompanying descriptions, the latter being in 

 English and in Japanese. From its geographical 

 position, especially its great range in latitude, 

 Japan shows a much more varied flora than any 

 other country of similar area, from the tropical 

 vegetation of Formosa to the alpine floras of the 

 high mountains and the semi-arctic flora of the 

 extreme north. The descriptions, though brief, 

 contain much that is of interest ; for instance, we 

 learn that when the curious "luminous moss," 

 Schistostega osniundacea, was discovered in one 

 of the habitats depicted in the atlas, the Japanese 

 Government immediately acceded to Prof, 

 ^fiyoshi's request that the locality should be made 

 a nature reserve. It is interesting to note that 

 in this series several species of wide range in the 

 temperate regions and familiar members of the 

 British flora are described as growing along with 

 characteristic Japanese flowering plants, the latter 

 including various species well known in Britain 

 as cultivated plants. 



Materials of Machines. By A. \\'. Smitn. 

 Second edition. Pp. v + 215. (Xew York: 

 John Wiley and Sons, Inc. ; London : Chap- 

 man and Hall. Ltd., 1914.) Price 55. 6d. net. 

 This book furnishes a very elementary treatment 

 of the manufacture and properties of materials 

 used in the construction and operation of 

 machines. In the first part the author deals 

 with fuels, refractory materials, electric furnaces, 

 and the metallure^y of iron, steel, copp>er, lead, 

 tin, zinc, and aluminium in rather less than ninety 



NO. 2364, VOL. 94] 



pages of a small book, and remarks in his preface 

 that an understanding of this is essential to the 

 study of the second part, which in 102 pages 

 treats of the testing of materials, the iron-carbon 

 equilibrium, cast iron, wrought iron, steel, its 

 heat treatment, and non-ferrous alloys. The final 

 ten pages are devoted to the selection of materials 

 for the various parts of a steam-engine. Seeing 

 that the metallurgical section of the book deals 

 exclusively with the extraction of Xhe metalsi 

 named from their ores, and ignores their mechani- 

 cal treatment, the only connection between parts 

 i. and ii. relates to the metals and alloys, e.g., 

 cast iron and cast steel which are used in the 

 cast state. Considering that the great bulk of 

 the various steels used in machines are 

 "worked," this omission must be regarded as un- 

 fortunate. It is certainly an astonishing thing 

 that the author, who is an .American, should ap- 

 parently not know the modern processes of ex- 

 tracting copf>er which have been developed 

 entirely in his own country, and should have 

 described a process which originated in Swansea, 

 i and has been superseded by them. To describe 

 I the metallurgy of copper in fewer than five pages 

 j as attempted by the author is a task that few 

 j metallurgists would undertake. 



I 



I Xerres. By Dr. D. F. Harris. (Home University 

 I Library.) Pp. 256. (London : Williams and 

 ' Xorgate, n.d.) Price 15. net. 



; Perhaps the most diflScult field of physiolc^n.- to 



j reduce to simple form and language, so that it 

 may be understood by the non-scientific lait}.", is 



! that of the nervous system. .Any attempt in this 

 direction, which is accurate, is sure of a welcome. 

 Prof. Harris, in the small volume under review, 

 has certainly succeeded in his attempt to explain 

 in non-technical language the place and powers 

 of the nervous system. He does not deal with 

 the question of the morphology and pure physio- 

 logy of the cerebrum and spinal cord, nor does 

 he consider psycholc^fA" — as physiology and 

 psychology have been dealt with already in other 

 volumes of the series. In reality the author deals 

 mainly with the reflex arc and its value to the 

 organism ; he also briefly discusses the causes 

 and the value of sleep to the organism, and con- 

 siders, very shortly, the conditions of "nervous- 

 ness" and "excitability," their nature, and the 

 possibility of their prevention. 



On the whole the author's statements are ex- 

 tremely clear and trustworthy, although some of 

 his generalisations are apt to be too sweeping. 

 For example, it will not be generally conceded 



i that "the transcendent nonsense of the post-im- 

 pressionist painters arose from absinthe-poisoned 

 blood " acting on an abnormal ner^-ous system. 

 Xor is the evidence that muscular activitv is the 

 result of the propagation of a special form of 

 energy generated from the Nissl granules of the 

 cerebral cells held to be, to say the least of it, 

 convincing. Still the book is interesting and is 

 worthy of its place in the series. 



