211 Notices respecting New Books. 



theories of Ampere and Weber, and compares them with those of 

 Helmholtz and Maxwell. 



In Part III. we have a clear and critical account of the theories 

 of Hertz and Lorenz. Zeeraan's phenomenon and its connexion 

 with Lorentz's theory are fully dealt with. We notice that on 

 p. 422 the author uses the terms ion and electron indiscriminately. 



Part IV. contains a sketch of Larmor's theory, and explains 

 very clearly its position relatively to the other theories. 



To those who, while interested in electromagnetic theory, yet 

 feel incompetent to examine critically the mutual relationship and 

 relative merits, as well as peculiar weaknesses, of the somewhat 

 perplexing tangle of rival theories, « e can strongly recommend 

 the perusal of this most suggestive and interesting book, the keen 

 critical insight of whose author enables him to pour a flood of light 

 on problems which appear obscure, and to state boldly and clearly 

 what is only implied or indirectly suggested by other writers. 



Leitfaden der WetterJcunde. Gemeinverstaudlich bearbeitet von 

 Dr. R. Bornstein, Professor an der Konigl. Landwirthschaft- 

 lichen Hochschule zu Berlin. Mit 25 in den Text eingedruckten 

 Abbildungen und 17 Tafeln. Braunschweig : E. Vieweg und 

 Sohn, 1901. Pp. viii-r-181. 



The subject of meteorology is one which may be rendered either 

 most fascinating or exceedingly dry— so much depends on the 

 method of treatment adopted. We congratulate the author of the 

 little book before us on the amount of interest which he has 

 succeeded in infusing into his subject. While strictly scientific in 

 his manner of dealing with the complex phenomena with which 

 the study of meteorology is concerned, the author has succeeded 

 in producing a book which may be picked up at any moment by a 

 person of ordinary intelligence, and read with as much interest 

 and pleasure as if instruction were not its main object. It is a 

 popular book in the highest and best sense of the term. 



The study of the weather involves the consideration of six meteor- 

 ological elements : temperature, moisture, cloud-form, rainfall, 

 barometric pressure, and wind. The author accordingly deals with 

 these in succession, and explains their connexion with the weather 

 in a manner which leaves little to be desired, and which practically 

 pre-supposes no knowledge on the part of the reader. The more 

 important instruments used in meteorological observatories are 

 illustrated and briefly described. The beautiful coloured pictures 

 of cloud-forms at the end of the book deserve special mention. 

 Of considerable interest is the last section of the book, which 

 deals with the arrangements adopted in different countries for 

 supplying weather forecasts. Copious bibliographical references 

 and an index enhance the value of this most useful and interesting 

 little book. 



