684 SCIENCE PROGRESS 



the Physical Universe According to the Space-Time Potential ; Non-New- 

 tonian Dynamics ; Electrolytic lonisation and Cell Action. 



Mr. Reuterdahl's chief contention is that it is impossible to sustain a 

 purely mechanistic interpretation of the universe, and that the attempts to 

 do so rest upon question-begging conceptions and arguments. For instance^ 

 Mass, Force, and Energy are conceived in such a way that each of them 

 involves the others ; not one of them is defined independently, so that in the 

 end none of them is really explained or accounted for. The plausibility of 

 such transparent fallacies is due to the deceptive smoke-screen of intricate 

 mathematics. On a strictly mechanistic basis the whole phenomenon of 

 interaction is quite unintelligible. The actual facts of cosmic activity and 

 becon ing necessitate, according to Mr. Reuterdahl, the assumption of a Tran- 

 scendent yet Immanent Activity Principle (God). The cosmic elements, 

 according to our author, are " Monons " (i.e. primordial, but created activity 

 centres), " Energor.s " (i.e. gyratory groups of Monons), " Vitons " (i.e. 

 primordial life-centres), and " Souls " (i.e. primordial centres of consciousness). 

 Out of these elements the universe has been constructed by God, who also 

 maintains it in existence and in running order. 



Mr. Reuterdahl's critical work is much more satisfactory than his con- 

 struction. His ideas may be right, but they are expressed dogmatically and 

 rhetorically rather than justified calmly and philosophically. In fact, the 

 tone of the book is sometimes more scholastic than scientific ; and a breath 

 of religious propaganda seems to stir among its leaves. Mr. Reuterdahl may 

 be justified in his taunts against that maid-of-all-work, the ether, endowed 

 by different men of science with such conflicting properties and functions. 

 He describes it as a kind of glue with which materialistic scientists try to keep 

 the world together. He complains that ether is a materialistic substitute 

 for God. But Mr. Reuterdahl does not appear to do much more than substi- 

 tute God for Ether — a deus ex machine who creates and sustains our author's 

 world of " monons," energons," " vitons " and souls, and solves all his 

 difficulties. It may be a sage thing for the layman to say " God knows," 

 whenever he is called upon to account for what he does not understand ; but 

 that is not science. Nor is it science to explain the unknown by the Unknown. 



At the same time there are many interesting things in Mr. Reuterdahl's 

 book, and those who are interested in the kind of problems which it treats of 

 will find in it much that is suggestive, even if they do not always see eye to 

 eye with the author. A. Wolf. 



BOOKS RECEIVED 



(Publishers are requested to notify prices.) 



Cours Complet de Mathematiques Speciales. Par J. Haag, Professeur a la 

 Faculte des Sciences de Clermont-Ferrand. Tome II. Geometric. 

 Paris : Gauthier-Villars et Cie, 55 Quai des Grands-Augustins, 192 1. 

 (Pp. vii + 662). Price 65 frs. 



Applied Calculus. An Introductory Textbook. By F. F. P. Bisacre, O.B.E., 

 M.A., B.Sc, A.M.Inst. C.E. London : Blackie & Son, 50 Old Bailey, 

 1921. (Pp. XV + 446). Price los. bd. net. 



New Mathematical Pastimes. By Major P. A. MacMahon, R.A., D.Sc, Sc.D., 

 LL.D., F.R.S., St. John's College, Cambridge. Cambridge : at the 

 University Press, 192 1. (Pp. x + 116.) Price 12s. 6d. net. 



La Loi de Newton est la Loi Unique. Theorie Mechanique de I'Univers. 

 Par Max Franck. Paris : Gauthier-Villars et Cie, 55 Quai des Grands- 

 Augustins, 1921. (Pp. 138.) 



Introduction to the Mathematical Theory of the Conduction of Heat in Solids. 

 By H. S. Carslaw, Sc.D. (Camb.), D.Sc. (Glasgow), F.R.S.E., Professor 

 of Mathematics in the University of Sydney. Second edition, com- 



