NOVEMBEK 29, 1912] 



SCIENCE 



745 



There are other novel and important fea- 

 tures of the Poulsen system which it would 

 take too long to mention. As yet only a be- 

 ginning has been made in developing its possi- 

 bilities. The nest step will be to test and put 

 in use generators of increasing powers, from 

 which increasing ranges are expected. The 

 success so far attained has advanced the sci- 

 ence of communication considerably beyond 

 its generally recognized limits, and affords 

 sound basis for the expectation that a few 

 years will see much of the present work not 

 only of ocean cables but also of long distance 

 telegraph lines done by undamped electro- 

 magnetic waves transmitted through space. 



Egbert Anderson 



Washington, D. C, 

 November 6, 1912 



PICTURES OP PSYCHOLOGISTS 



Having the Open Court series pictures of 

 psychologists and philosophers, I have often 

 wished that I had those of present-day psy- 

 chologists on the walls of my recitation room. 

 I have often thought of writing to psychol- 

 ogists for their photographs, but that would 

 be a good deal of trouble and if a number fol- 

 lowed that plan it would become a nuisance to 

 those whose pictures were most desired. A 

 continuation of the Open Court series would 

 be desirable, but who is to decide which of the 

 living men should be included and would not 

 such a series be unprofitable because of its in- 

 clusions and omissions? 



The following plan occurs to me as a means 

 of getting what is desired without any of the 

 above disadvantages. Let those desiring 

 photographs name the ones whose pictures are 

 desired to the one who is willing to take 

 charge of the matter. That one can then pro- 

 cure one photograph of each person named 

 and have a plate made from it of the same 

 size as the Open Court series and arrange with 

 a photographer to furnish photos from these 

 plates at a reasonable rate. 



Are there enough who desire such pictures 

 to make it worth while to inaugurate the plan ? 

 This can be answered if all who are interested 



will at once write to me signifying their de- 

 sires and naming at least a few of the men 

 whose pictures they wish. Prominent educa- 

 tors and perhaps other men of science might 

 be included if they were asked for. If inter- 

 ested do not fail to write at once. 



E. A. KlEKPATEICK 



FiTCHBUKG, Mass. 



SCIENTIFIC BOOKS 

 The Spider Boole. A Manual for the Study 

 of the Spiders and Their Near Eelatives, 

 The Scorpions, Pseudoscorpions, Whip- 

 scorpions, Harvestmen, and Other Mem- 

 bers of the Class Arachnida, Found in 

 America north of Mexico, with Analytical 

 Keys for Their Classification and Popular 

 Accounts of Their Habits. By J. H. CoM- 

 STOCK. Garden City, New York, Double- 

 day, Page & Co. 1912. Pp. xv + 70Y; 

 in figs. 



This work, the most recent of the series of 

 well-known nature books published by Double- 

 day, Page & Company, fills a long-felt need, 

 since the spiders are the most abundant and 

 conspicuous representatives of a large group 

 of organisms, which have never aroused an in- 

 terest, in the American student at least, at all 

 commensurate with their biological and eco- 

 nomic importance. The author has arranged 

 the vast amount of material, which he has ac- 

 cumulated during more than a decade of en- 

 thusiastic study, in conformity with the plan 

 adopted in the preceding volumes of the series, 

 throwing the emphasis on the classification 

 and subordinating the morphological, eth- 

 . nological and chorologieal data to this 

 arrangement. By way of introduction to 

 the main subject of the volume the vari- 

 ous lower groups of Arachnida are briefly 

 discussed. This portion of the work, apart 

 from the useful tables for identification, does 

 not rise above the level of many zoological 

 text-books, and some of the sections, as, e. g., 

 those on the ticks and mites, scarcely do jus- 

 tice to our present knowledge or to the eco- 

 nomic importance of the subject. The ac- 

 count of the spiders, which are, after all, the 

 subject of the book, is preceded by chapters on 



