October 13, 192 1] 



'NATURE 



207 



those of the Rev. F. Ball, R.X., and of Capt. 

 Aquino, of the Brazilian Navy, Mr. S. Ogura, the 

 inventor of the method, commences by assuming 

 such a point upon the chart that latitude and hour- 

 angle are each represented by an exact number of 

 degrees. In the subsequent procedure, however, 

 he differs wholly from the methods of his pre- 

 decessors, and by means of but one special table, 

 occupying only eighteen pages, carries out his 

 purpose in a manner which, in point of simplicity, 

 is certainly not inferior to anything that has gone 

 before. A second table of about nine pages is 

 added, but this is nothing more than a specially 

 arranged table of logarithmic secants, convenient, 

 but not in any way indispensable to the principle 

 upon which the method is based. 



Other new and original tables given in the 

 volume are those for finding azimuth, identifying 

 an unknown star, and so forth, and the contents 

 afford a fresh proof that no effort is spared bv the 

 Japanese naval authorities to keep in close touch 

 with the many developments in the science of 

 navigation that have taken place in recent vears. 



Le Destin des Etoiles : Etudes d'Astrononiie 

 Physique. By Svante Arrhenius. Traduction 

 francaise par T. Seyrig. (Nouvelle Collec- 

 tion scientifique.) Pp. \ + 22^. (Paris: Felix 

 Alcan, 1921.) 8 francs net. 



The course of development of suns and planets 

 from the primitive nebula to planetary- death is 

 discussed in this book. It deals first with the 

 Galaxy, describing the conclusions of Wolf, 

 Easton, Seeliger. Charlier, and Shapley on its 

 extent and structure. The author ascribes the 

 two great star streams to the interpenetration of 

 two cosmic clouds, the rapid rotational motion 

 of certain nebulae that is revealed by the spectro- 

 scope being supposed to arise from' the collision 

 of nebulous masses in the course of this inter- 

 penetration. He holds that the dark regions in 

 the Galaxy have been swept clear by the passage 

 of cosrpic clouds. 



Several chapters are occupied with planetary 

 atmospheres and with the changes that thev prob- 

 ably undergo in the course of the planet's develop- 

 ment. It is suggested that free oxvgen is not 

 present until the surface is sufficientlv cool to be 

 fit for the support of life. The habitability of the 

 planets is also discussed, the moon and Mercurv 

 being classed as dead worlds, Mars as possibl'v 

 supporting low forms of vegetation, while Venus 

 IS supposed to be in the carboniferous stage. 



The book can be recommended for its bold 

 speculations, which include in their scope much 

 recent observational work. 



A. C. D. Crommelix. 

 Kentucky Superstitions. By Dr. D. L. Thomas 

 and Lucy B. Thomas. Pp. viii4-334. (Prince- 

 ton, X.J. : Princeton University Press ; London : 

 Oxford University Press, 1920.) 125. 6d. net. 

 Until recently Kentucky was the most remote 

 and primitive of the States of America. Among 

 the Mountain whites, as is well known to students 

 NO. 271 1, VOL. 108] 



of American social conditions, the law did not 

 run; they lived in conditions which were practic- 

 ally tribal, and the most prominent features in 

 their social habits were the blood-feud and the 

 illicit still. The Lowland whites and negroes, the 

 remaining elements in the population, were also 

 very little touched by outside influence. It is 

 therefore not surprising to find that the compilers 

 of this collection have been able to get together 

 more than four thousand instances of super- 

 stitions, among which a firm belief in witchcraft 

 and in the efficacy of charms and magical cures in 

 illness figures prominently. A large proportion 

 of these beliefs will be familiar to students of 

 British folklore. As the Kentucky population was 

 derived mainly from the Carolinas, Maryland, and 

 \'irginia, these superstitions have a pedigree 

 going directly back to England in the seven- 

 teenth century. The authors consider that the 

 negro has assimilated white folklore, his only 

 contribution being the Voodoo or Hoodoo beliefs. 

 Certain elements, however, suggest that a closer 

 examination might modify this view. 



Notes on Dynamics, with Examples and Experi- 

 mental Work. By Terry Thomas. Pp. 123. 

 (London : Crosby Lockwood and Son, 1920.) 

 65. net. 

 The "notes" issued by Mr. Thomas deal with a 

 fairly wide range of dynamical problems, and 

 there are hundreds of excellent exercises, but this 

 is all one can say in their favour. The diagrams 

 are very roughly drawn, and the whole style of 

 the book is reminiscent of the student's lecture 

 notes. Thus one must object to a statement like 

 "The engineer unit of mass is M/g, where Mis the 

 mass in pounds, and ^ = 322 "; or "The various 

 forms of energy are: potential, kinetic, heat, 

 electrical, and chemical " ; or " Neglecting the 

 effect of the axle, the moment of inertia of a flv- 

 wheel is MR-/ 2," without saying anything about 

 the construction of the flywheel; or "1^ = 1^;+ I,," 

 in dealing with moments of inertia, without men- 

 tioning that this refers to a plane lamina. 



The author is of the opinion that it is much 

 safer for beginners to reduce all forces to poundals 

 and dynes, and carries this doctrine so far as to 

 introduce the term "tondal." This is an interest- 

 ing opinion, but it is very doubtful whether many 

 teachers will agree with it. 



S. Brodetskv. 



Countryside Rambles. By W. S. Furneaux. 

 (New Era Library.) Pp. hi -f 186. (London: 

 George Philip and Son, Ltd., n.d.) 35. 6d. net. 

 .\s a populariser of natural history Mr. Furneaux 

 is already well known. In the present volume the 

 contents of which are arranged in accordance with 

 the four seasons, attention is directed to many 

 of the more striking objects and phenomena, 

 chiefly botanical and zoological, that are likely 

 to come within notice during walks in the country. 

 It is lightly and pleasantly written, and the forty- 

 six plates of photographic illustrations are verj' 

 successful. 



