August 15, 1913] 



SCIENCE 



231 



In order to review a book it is at least ex- 

 tremely desirable to have read it. Eeading 

 the encyclopedia is not " jedermann's Sache " 

 and, unlike Agamemnon in the story of the 

 Peterkin family, the present writer can not 

 pretend to have done it, but he has at least 

 carefully examined each of the forty-six 

 " Lieferungen " of 160 pages each, which have 

 so far appeared of this admirable work, and 

 has perused with care many of the articles on 

 which he is competent to have an opinion. 

 The first thing that must certainly strike the 

 scientific man on opening this work is the 

 feeling of regret that it is impossible to pro- 

 duce such a work in America, and, secondly, 

 that, if it were, no publisher could be found 

 to undertake it, for the, to him, very con- 

 vincing reason that he would not be able to 

 make any money out of it. Germany is pre- 

 eminently the country of encyclopedias, and 

 if one can judge of German greatness from 

 the thoroughness with which they go about 

 the manufacture of these aids to knowledge ha 

 can but wonder why the Germans have not 

 already conquered the world. To be sure 

 France is the home of what must always be 

 known as the encyclopedia, to say nothing of 

 Larousse and similar undertakings, and Eng- 

 land is the home of eleven editions of the 

 Britannica, to which in these latter days 

 American methods of scientific management 

 and booming have been added as well as 

 British and American learning; but when we 

 look at the " Encyclopaedie der mathema- 

 tischen Wiasenschaften," which has been ap- 

 pearing now for thirteen years, and is not yet 

 complete, and which has compelled the French 

 to publish a French edition based with great 

 fidelity upon it, we must admit the impossi- 

 bility of competition in this line. 



The present work is, so far as known to the 

 reviewer, the first attempt made, even in Ger- 

 many, to produce an encyclopedia of all the 

 natural sciences, and must put aU scientists, 

 as well as all liberally educated laymen who 

 can read German (and the contrary is a nega- 

 tion of terms) under great obligations to tha 

 house of Fischer, so well known among the 



great publishing houses of scientific works. 

 It seems rather a pity that mathematics could 

 not be included, because, although not a nat- 

 ural science, it is, if not the greatest of the 

 sciences, at least the conunon tool and com- 

 petent servant of all. Of course mathematics 

 is taken care of in the great work named 

 above, but that is no reason that it should not 

 have been treated in a briefer and less tech- 

 nical way in a work of the scope of the present 

 one, and its exclusion results in the inclusion 

 of articles largely of a mathematical nature, 

 such as the one on Fliissigkeitsbewegung, 

 which appear in the mathematical encyclo- 

 pedia by the nature of things, and also appear 

 here as physical articles. In this connection 

 the reviewer may perhaps be permitted to 

 animadvert on the absurd classification of 

 mathematics with philosophy, say in the group 

 system at Harvard, which removes it from its 

 closest friends and relatives, physios, astron- 

 omy and chemistry, and puts it along with an 

 almost total stranger, and calls it to the atten- 

 tion of people most of whom are totally unable 

 to use it. So much for logic, so little for 

 common sense. 



What most impresses the reader of the work 

 under consideration is the great competence of 

 the writers of the articles, and their absolute 

 up-to-dateness. To be sure, some of the au- 

 thors are decidedly young, but their articles 

 are none the less good, and we must bear in 

 mind the great number in Germany of bril- 

 liant minds among very young men, at least in 

 physics. As an example of contemporaneous- 

 ness we find in the extremely interesting ar- 

 ticle on Fliissigkeitsbewegung by Professor 

 Prandtl, of Gottingen, mention of the most 

 recent researches on fluid resistance, illus- 

 trated by a beautiful photograph of vortex- 

 motion, involving work done only last year, 

 while the famous principle of relativity, which 

 was invented only in 1905, is treated in several 

 articles, although not under a special heading. 

 The articles on radioactivity and other radia- 

 tions, those on Luftfahrt and Luftpumpe are 

 further examples, the latter giving an excel- 

 lent description of Gaede's new molecular air 

 pump, a characteristically German invention. 



