July 27, 1900.] 



SCIENCE. 



139 



differs from the German plan in the arrange- 

 ment of the symbols, being much simpler. 

 The method will be explained in print be- 

 fore long. 



It is gratifying to note the increasing and 

 continued interest in bibliography on all 

 sides, and the Committee stands ready to 

 encourage the movement in chemistiy by 

 practical assistance to those desirous of con- 

 ti'ibutingto the now considerable list of in- 

 dexes. Address correspondence to the Chair- 

 man, at the Cosmos Club, Washing-ton, D. C. 

 Committee : 



H. Caeeington Bolton, Chairman. 



F. "W. Claeke (in Europe), 



A. E. Leeds, 



A. B. Peescott, 



AlFEBD TtrCKEEMAN, 



H. W. Wiley. 



SCIENTIFIC BOOKS. 

 A Text-hook of Physics. By W. Watson, 

 A.R.C.S., B.Sc. (London), Assistant Professor 

 of Physics at the Koyal College of Science, 

 London. London, Longmans Green & Co. ; 

 New York, The Macmillan Company, 66 Fifth 

 Avenue. Price, $3.00. 



This book deserves the careful attention of 

 those teachers who are allowed with their stu- 

 dents sufficient time to develop an elaborate 

 course in general physics. It will be especially 

 suited to their needs if their students are able 

 to take an interest in the more abstract parts 

 of the science. For those who are limited in 

 time, or who are not in position to do rather 

 advanced work, it will not be so useful. The 

 book is almost as long as Atkinson's 'Ganot,' and 

 contains a much larger amount of matter that 

 requires thought and study than that well- 

 known work. In order to condense it as much 

 as possible the author has excluded elaborate 

 illustrations and descriptions of apparatus. 

 The space thus gained is used for the discussion 

 of elementary points of theory or for the men- 

 tion of modern theories and results. The book 

 is consequently not one which can be read 

 hastily or with large omissions, and to go 

 through it thoroughly with a class will require 



at least four hours a week for a year. As a 

 book of reference, both for students and teachers, 

 it will be found to be of considerable value. 



The order in which the various subjects should 

 be presented which are comprised under the 

 general title of physics has always offered diffi- 

 culties to the writers of text-books. Mr. Wat- 

 son has used an order which to some extent is 

 new, and which is designed to avoid anticipat- 

 ing principles or theorems which have not been 

 established. He has succeeded perhaps as well 

 as anyone can in an effort in which complete 

 success is impossible. The principal features 

 of his arrangement, which are not of the con- 

 ventional form, are : the development of the 

 kinetic theorj^ of gases under the head of Proper- 

 ties of Matter, before the subject of Heat has 

 been introduced ; the treatment of wave mo- 

 tion on the surface of liquids in immediate an- 

 ticipation of the subject of Sound, the subject 

 of Wave Motion and Sound following Heat 

 instead of preceding it in immediate depend- 

 ence on Mechanics ; the division of the Electro- 

 magnetic Relations of the Electric Current into 

 two parts, separated by a considerable inter- 

 val ; and a similar division of Magnetism bj^ 

 the omission of Magnetic Induction from the 

 chapters where it usually is given and its in- 

 sertion later, just before the presentation of 

 Electromagnetic Induction. 



The most serious defect in the book is the 

 inadequate treatment of the subjects of moment 

 of force and of the properties of the center of 

 mass. Judging from what the author says in 

 connection with his description of the properties 

 of the physical pendulum, his treatment of these 

 subjects and of others allied to them was de- 

 termined because of the mathematics involved 

 in a fuller presentation. It has, however, been 

 demonstrated by experience that a method such 

 as that used in Selby's ' Mechanics ' furnishes a 

 satisfactory foundation for the study of mo- 

 ments of force and of the uniplanar motion of 

 rigid bodies, and that this method is easily com- 

 prehended by students. The mathematics in- 

 volved in it are no more difficult than those 

 used throughout this book. 



We have noticed a few errors of statement, 

 some of which may be mentioned, as they 

 would embarrass a student. Thus (p. 27) the 



