DISCOVERY 



137 



that part ceded to Finland by the Treaty of Dorpat, 1920. 

 A movement for autonomy in Careha followed the Rus- 

 sian Soviet revolution and, fanned by Finnish sympathy, 

 now takes the form of a demand for union with Finland. 

 The main arguments against this wish, apart from the 

 opposition of the Russian Soviet, are, first, that the mino- 

 rity of Finns and Carelians in the Kola peninsula would 

 not justify its inclusion in any cession of territory, and the 

 result, if Carelia were ceded, would be a detached portion 

 of Russian territory ; and, secondly, that the loss of 

 Carelia would cut the important Murman railway which 

 affords Russia access to an ice-free port on the Arctic 

 coast. The volume is a genuine contribution to know- 

 ledge, and the authors leave facts to speak for them- 

 selves, laying little stress on the propagandist side of 

 their task. R. N". R. B. 



THE EVOLUTION OF THE EARTH 



Earth Evolution and its Facial Expression. By William 

 Herbert Hobbs. (Macmillan & Co., Ltd., 155.) 



This book embodies the views of the author, a professor 

 in the University of Micliigan, on the evolution of the 

 earth and its facial expression ; it is a vigorous exposition 

 that will interest not only the geologist, to whom it is 

 primarily addressed, but also the general reader who is 

 interested in this subject. Professor Hobbs gives a clear 

 and useful summary of the evidence that has accumulated 

 against the now almost abandoned nebular hypothesis of 

 the origin of the world, and points out how foolish people 

 were ever to have believed in it. He is against any theory 

 which describes the interior of the earth as molten ; he 

 disbelieves, as do many others, in the relative permanence 

 of the great oceans, and dismisses summarily the idea that 

 the presence of radio-active substances compensates to 

 any degree for the loss of heat from the earth by radiation 

 into space. 



He believes that the earth is in process of shrinking 

 from the form of a sphere (in which the ratio of volume 

 to enclosing surface is a maximum) to that of a regular 

 tetrahedron, in which this ratio is a minimum, and the 

 most valuable part of the book contains an exposition of 

 this hypothesis. The author beUeves also that the age 

 of the earth has been quite unnecessarily exaggerated ; 

 he thinks that twenty-four million years is sufficient to 

 account for all known geological phenomena. 



The general reader cannot but admire the freshness of 

 outlook and the originality of some of Professor Hobbs' 

 ideas, even when possibly he is riding off at a tangent. 

 He is against conventionality of thought on geological 

 subjects, or bowing the knee to the opinions of great men. 

 As an example ; 



" Anyone who has examined into the history of the 

 theories of earth evolution must have been astounded to 

 observe the manner in which the unique and the difficultly 

 explainable has been made to take the place of the common . 

 and the natural in deriving the framework of these 

 theories. The part of the accidental and fortuitous has 

 been by no means a small one in guiding the thoughts 

 and the speculations of those who have dealt with the 

 fundamental theories of the universe. 



" The unique rings of Saturn gave shape to the nebular 

 hypothesis. The almost unique properties of water near 

 its temperature of congelation was largely responsible for 

 the idea of a molten earth core, long the orthodox doctrine 

 of geological science. The unique rigid mass of Bohemia 

 near the arcs of Europe and that of India near those of 

 .\sia largely determined the form of the Suess conception 

 of arcuate mountains. . . . Those theories wliich have 

 come to receive general support . . . have quite generally 

 owed their success to the unusual prestige of their pro- 

 mulgators by reason of some outstanding piece of investi- 

 gation, though this may have been in a different field 

 from that of the theory that has been added to the body 

 of orthodox doctrine. This was notably true of Laplace 

 and his great work, the Meckaniqtie Celeste, in w-hich the 

 famous nebular hvpothesis is contained as an apparently 

 little considered afterthought appearing as an appendix. 

 . . . Once accepted by the leaders of thought, the position 

 of a new theory is one peculiarly immune from attack. 

 If its rise to prominence is in any way sensational, the 

 theory becomes, as it were, in a measure canonised and 

 clothed with a quahty of sanctity. Attacks upon it are 

 welcomed as little by the scientific profession as they are 

 by the promulgators of the theory. The Einstein theory 

 of relativity, which is just now in the saddle, receives 

 extravagant praise, and the voices of those who point 

 out its fallacies are lost in the thunder of applause." 



But at times Professor Hobbs is much less illuminating 

 and convincing. He is greatly enamoured of the idea 

 that the span of geological time has been greatly over- 

 estimated, and this, he believes, is largely due to "the 

 accident of location of those who have studied geological 

 processes. Had the early universities been located 

 within the Pacific area (where earthquakes are frequent) 

 rather than about the Atlantic ; had geologists made 

 their investigations w-ithin those belts of the earth wliich 

 are undergoing rapid change — the orthodox view con- 

 cerning the time which has been necessary for the accom- 

 plishment of the past geological changes would have been 

 found to be a fraction only of that which it is now 

 supposed to be." 



But what about the opposing evidence, that of the 

 physicists, which demands an age for the earth forty times 

 greater than Professor Hobbs' estimate ? He does not 

 discuss it, and in the only place where he mentions it, he 

 writes as though he did not properly understand it. 

 It is well to show how bees in men's bonnets and the 

 accidents of environment have twisted grotesquely the 

 truth that men have sought in the past, but views on 

 geological or any other problems cannot be generally 

 accepted if their author so patently neglects the conclu- 

 sions of men now living. A. S. R. 



BOOKS ON PSYCHOLOGY 

 Tlie Care of the Adolescent Girl. By Phyllis Blanchard, 

 Ph.D. (Kegan Paul, Trench, Triibner & Co., Ltd., 

 7s. 6d.) 

 The title of Dr. Blanchard's book does not give quite 

 a fair idea of its scope, for it is not an elementary hand- 

 book of useful advice, but a study of the psychology of 



