August 4, 1904] 



NA TURE 



317 



made the subject of that article his particular pur.^uit, 

 relaxation, or study; a trainer writing on training, 

 a breeder on breeding^, and so on. Under Mr. 

 Watson's able editinj.^, all these diverse factors have 

 been woven into one harmonious and continuous whole. 



To the naturalist the most interesting chapter is 

 : v-rhaps the one on breeders and breeding, in which 

 ! he writer strongly advocates the advisability of plenty 

 of fresh air and exercise for young horses of all kinds, 

 as well as change of pasture. Contrary to the opinion 

 of some of his fellows, the author firmly believes in 

 heredity, and therefore advises the selection for breed- 

 ing purposes of mares which have made a name on 

 the turf. 



As regards shape, he prefers long, low, and broad 

 animals, but it is somewhat curious to notice that in 

 :he chapter on trainers and training the writer con- 

 siders this an old-fashioned view, pointing out that 

 ' St. Simon," who was an3'thing but a long and low 

 norse, has done much to modify opinion on this point. 

 It is satisfactory to learn that, according to the last 

 mentioned writer, there is much less viciousness prc- 

 vah-nt among racehorses than was formerly the case, 

 this being attributed to gentler and more humane 

 methods of training and treatment. 



One other point and we must take leave of this 

 brightly written and well illustrated volume. The 

 point in question relates to the proper manner of draw- 

 ing a racehorse at full speed. As the frontispiece of Mr. 

 Watson's work we have a picture of a race in which 

 the horses are represented as seen in a photograph, 

 one of them having all four legs off the ground, and 

 I; oking as though it were about to fall on its nose. 

 In contrast to this, we have, facing p. 103, a repro- 

 duction of Herring's well known picture of " Flying 

 Dutchman," in which the horse is represented as 

 galloping ventre a terre, with the fore and hind limbs 

 stretched out to their full extent. Obviously it is an 

 inconsistency to have these two tvpes of representing 

 a galloping horse in the same work, as one must 

 obviously be wrong. From the fact that when we 

 dr;iw the wheels of a carriage in rapid motion we 

 represent the spokes as forming a continuous blur, and 

 not as seen in a photograph, our own opinion inclines 

 to the advisability of drawing racehorses somewhat 

 after the old conventional manner, and not as thev 

 appear in photographs, when the postures are quite 

 unlike the appearances presented to our eves. 



R. L. 



Gi. 'logic von Deutschland tind den angrenzenden 



Gebiclen. Zweiter Teil. Lieferung i. Bv Dr. 



Richard Lepsius. Pp. 246. (Leipzig : Engelmann ; 



London : Williams and Norgate, 1903.) Price S.f. 



net. 

 This part of the text elucidating Dr. Lepsius's well 

 known geological map of Germanv maintains a high 

 level, and secures the acceptance of the book as a per- 

 manent work of reference. It is not so redolent of the 

 country itself as is the great work on Austria-Hungary 

 recently noticed in these columns (May ig, p. 49), but 

 it embodies the results of extensive researches, and the 

 individualitv of the author is agreeablv seen when he 

 marshals and reviews the conclusions of those who 

 have gone before him. The present section is of 

 especial interest to students of metamorphic areas. 

 The amphibolites and marbles of the " kristalline 

 (irundlage im Erzgebirge " will recall many occur- 

 rences in our Scotch and Irish highlands. The de- 

 scription of the saturation of a schistose area by 

 invading granite (p. 104), and the consequent origin 

 of the gneissic massif of the Er/gebirge, will appeal 

 to those who have sought to show that our own 

 " Archsean " gneisses may often be of composite 



NO 1814. VOL. 70] 



origin, and in places of post-Silurian age. The famous 

 area of granulite in Saxony is dealt with from the 

 point of view so long maintained, in other regions, 

 by French geologists, to whom personal recognition 

 is accorded (p. 172). Dynamic metamorphism is rele- 

 gated to a relatively unimportant place, and the 

 granulite is treated as a part of the Carboniferous 

 granitic intrusion, making its way, under pressure of 

 superincuinbent layers, into a great dome of schists. 

 The pyroxene-granulites and other variations arise 

 from the absorption of diabases, quartzites, and so 

 forth, into the invading mass. The observations of 

 Callaway in Galway and Barrels in Brittany thus 

 receive confirmation from the stronghold of the 

 dynamometamorphic school. 



The present part also includes a description of the 

 sandstone area of the Elbe, with lists of Cretaceous 

 fossils, and of the post-Cretaceous overthrust (p. 182) 

 of granite and svenite on the right bank of the river 

 at Hohnstein. ' G. A. J. C. 



Traile Elcmentaire des Enroiilemcnis dcs Dyua)nos a 

 Courani Continu. By F. Loppe. Pp. vi + 78. 

 .(Paris: Gauthier-Villars, 1904.) Price 2 f. 75 c. 

 Etude siir les^ Resonances. By G. Chevrier. Pp. 76 



(Paris : L'Eclairage Electrique, 1904.) 

 M. Loppfe's little book is an elementary treatise on 

 dynamo windings which we have no doubt will prove 

 useful to many students of this subject. The treat- 

 ment is quite simple, and the mathematics required 

 are of the most elementary nature. The book is 

 divided into two chapters, the first dealing with bipolar 

 and the second with multipolar machines ; only ring 

 and drum windings are discussed. There are a 

 number of good diagrams and winding tables. 



The subject of resonance in electric cables carrying 

 alternating currents has already become of consider- 

 able importance in electrical engineering, and is likely 

 to come still more to the front as the development of 

 power distribution at high voltages proceeds. M. 

 Chevrier's book is a welcome essay on the subject, as 

 the author has endeavoured to coordinate the existing 

 knowledge and to present the elements of both the 

 theoretical and practical aspects in a clear manner. 

 .After a general discussion of oscillating motion, 

 electric circuits are considered in detail, and the various 

 cases of resonance or possible resonance in distributing 

 mains are treated at some length. 



l.chrbucli der experimental Physik in elementarer 

 Darstellung. By Dr. Arnold Berliner. Pp. xvi-l- 

 857 ; with plates and illustrations. (Jena : Gustav 

 Fischer, 1903.) Price 14 marks. 

 This is an elementary but not a rudimentary treatise. 

 The aim of the author has evidently been to present as 

 completely as possible the fundamental principles and 

 facts which form the groundwork of physics (including 

 mechanics). It can be confidently recommended to 

 any second or third year student of experimental 

 physics who is familiar with German. The mathe- 

 matics in it is of a very elementary character; the 

 author relies, in fact, not on mathematical demon- 

 strations, but on gf.ieral descriptions aided by 

 diagrams. Many of these diagrams are very well 

 conceived, and materially assist the description in the 

 text. The author is fond of the use of analogies, and 

 we think him very successful in employing them. 

 We were rather surprised to find the Boer war figuring 

 as one of these analogues. 



The book will be found most useful to those students 

 whose mathematical knowledge is only slight. The 

 medical student has, in fact, been kept in view in its 

 elaboration. 



