484 Notices respecting Neio Books. 



the loss in air at atmospheric pressure in this case was 1/14 

 per cent at the same temperature. 



The experiments described above show that the disintegra- 

 tion in air is conditioned by the presence of oxygen, as 

 Nahrwold thought. They do not prove that the presence of 

 both nitrogen and oxygen may not be a necessary condition. 

 Kaufmann, however, has found that in pure oxygen the dis- 

 integration is six times as great as in ordinary air. 



LIV. Notices respecting New Books. 

 Outlines of Physical Chemistry. By A. Reychler, Professor of 



Chemistry in the University of Brussels. Translated by Dr. J. 



McCrae, Demonstrator of Chemistry, Yorkshire College, Leeds. 



London : Whittaker & Co., 1899. 

 r PHE student who wishes to acquire a knowledge of the elements 

 -*- of physical chemistry will find this volume well adapted to 

 his purpose. It assumes the reader to be acquainted with the 

 simpler phenomena of physics, and to have worked through 

 courses of inorganic and of organic chemistr}'. The laws of the 

 gaseous state, the determination of vapour-densities, and the cases 

 of abnormal vapour-density are first described ; these are followed 

 by a discussion of Dulong and Petit's law, and the corresponding 

 law of Neumann for compound molecules. The subjects of valency 

 and the use of structural formulae complete this section of the work, 

 which is devoted to fundamental theories. The second portion, 

 treating of the three states of matter and their special properties, 

 in detail, introduces the kinetic theory of gases and the phenomena 

 of transition from gas to liquid ; the discussion of liquids includes 

 molecular refraction, rotation of plane of polarization and stereo- 

 chemistry, osmotic pressure, and vapour pressure of solutions. In 

 the third pa rt-ther mo-chemistry and electro-chemistry are described, 

 the latter leading naturally to the special properties of salt solu- 

 tions and the ionic theories. The fourth and last section includes 

 chemical dynamics, with examples of equilibrium and of reactions 

 taking place at a measurable rate. It will thus be seen that the 

 book covers much ground, and is therefore necessarily of an ele- 

 mentary character. The relative importance of the various parts 

 of the subject is well represented by the amount of description given 

 to them, so that the student may obtain a good idea of the nature 

 and extent of the subject. 



The part of the work performed by Dr. McCrae has not been 

 merely that of the translator. By collaboration with the author 

 he has secured the almost simultaneous issue of the revised 

 Belgian edition of the work and of the present translation of it. 

 We learn from the author's preface that many improvements on 

 the original edition have resulted from suggestions by the late 

 Dr. F. Hurter, who was engaged on the translation at the time of 

 his death, and by the present translator who has rewritten and 

 completed it. J. D. H. 



