Chemistry and Physics. 231 



the old. For until the positive nucleus is in some way disposed 

 of we have a primordial element which is quite on a parity with 

 the conception of mass. And again, for example, the corpuscu- 

 lar radiation of an energy cell into a non-thing does not give a 

 very satisfactory picture of what we ordinarily understand by an 

 electro-magnetic wave. 



The translation has been made by Morton Masius with the 

 intention of giving the author's views a wider circulation. 



F. E. B. 



8. The Chemical Effects of Alpha Particles and Electrons; by 

 Samuel C. Lind. Pp. 182. New York, 1921 (The Chemical 

 Catalogue Co.). — This is one of a series of scientific and technol- 

 ogic monographs projected by the American Chemical Society, for 

 which the editors have selected writers who are recognized as 

 authorities in their respective fields. It is believed that when 

 men who have spent years in the study of important subjects are 

 willing to co-ordinate their knowledge and present it in concise 

 and readable form they will perform a service of the highest value 

 to their fellow chemists and also by furnishing a well digested 

 survey of the progress already made in that field they will assist 

 in promoting research by pointing out directions in which investi- 

 gation needs to be extended. 



The contents of the present volume would properly be 

 described by the title radio-chemistry on the analogy of electro- 

 chemistry, thermo-chemistry, etc., except that the former term has 

 been frequently used to describe the separation or preparation of 

 the radioactive elements which are topics not here considered. 

 The first three chapters outline the scope of the work, the nature 

 of radioactivity, the general properties of the radiations and their 

 ionizing effects. Six succeeding chapters take up both the quali- 

 tative and quantitative chemical reactions produced by the radia- 

 tions in considerable detail. Chapter X is devoted to the cog- 

 nate subject of photo-chemical reactions. In Chapter XI the 

 author discusses positive rays, recoil atoms, and summarizes the 

 present knowledge and most recent work on isotopes. In the final 

 chapter will be found a brief discussion of Eutherford's rather 

 startling discovery of atomic disintegration by the alpha par- 

 ticles. Very full indices of both subject matter and authors are 

 provided at the end. These together with foot-notes in the text, 

 giving references to the original papers, supply a satisfactory 

 bibliography of all the subjects treated. Various tables and dia- 

 grams are also reproduced. 



The typography of the mathematical formulae is apparently by 

 a compositor who is not used to work of that character. Ambig- 

 uities or errors have been noticed which make it desirable that the 

 original authority be consulted before a formula quoted is 

 submitted to any important calculation. f. e. b. 



