Notices respecting New Boohs. 487 



Differential Equations. By H. Bateman. Pp. xi-}-306. Long- 

 mans, Green & Co. Price 16s. net. 

 In his preface the author states that he has endeavoured to 

 supply some elementary material suitable for students studying 

 the subject for the first time, and some more advanced work for 

 mathematical physicists. We scarcely think that the book will 

 appeal to young students, for such elementary matter as it contains 

 is handled in a way too general and too little explicit to be 

 grasped by a mind of small mathematical experience. To the 

 more practised mathematician, however, the author offers an 

 attractive treatment of the differential equations of types most 

 commonly met with in physical problems, together with a chapter 

 on mechanical integration which contains an account of Pascal's 

 recent work. The book is completely in touch and sympathy with 

 the most modern methods, and frequently introduces applications to 

 recent work in mathematical physics, such as the author's treat- 

 ment of the system of linear equations governing successive radio- 

 active transformations, and Lorentz's electron theory equations. 



There is an excellent selection of problems taken from a wide 

 range of sources, and ample references for those who wish to 

 pursue deeper the study of any particular subject. While the 

 book is, perhaps, not well suited to form a first introduction to the 

 subject, it is admirably adapted to be used in conjunction with 

 one of the standard textbooks, and cannot fail to be useful to 

 students of mathematical physics, especially those interested in 

 research on this subject. 



A History of Chemistry . By F. J. Moobe, Ph.D. Pp. xiv-f 292. 

 McGraw-Hill Book Company, New York, and Hill Publishing- 

 Company, 6 & 8 Bouverie Street, London, E.C. 4. Price 

 12s. 6d. net. 

 The value of a knowledge of the history of science in studying 

 modern theories is fast being realized, and nowhere more so than 

 in America. It is hard to find a subject of greater intrinsic 

 interest, and on the history of chemistry Professor Moore writes 

 with a knowledge and enthusiasm that makes his little book a 

 fascinating one. A prominent feature are the illustrations, which 

 not only include a wide range of portraits, from Basil Valentine to 

 Sir Ernest Rutherford (this last a most excellent portrait), but 

 also pictures of historical apparatus and laboratories, which give a 

 clear idea of the conditions in which the older investigators carried 

 out fundamental experiments and measurements of surprising 

 accuracy. A praiseworthy effort is made to concentrate on work 

 which has proved really basic in character. The book is notable 

 in that the early developments, which receive much attention in 

 most histories of chemistry, are comparatively briefly treated, 

 attention being concentrated on the hard task of giving some idea 

 of the great w T ork of the nineteenth century and after. This has 

 been very successfully carried out, with a good sense of proportion. 

 The account is carried right down to the present day, and includes 

 a description of the recent work on X-ray spectra and Moseley's 

 atomic numbers. No student of science can fail to be interested 

 bv this book. 





