Chemistry and Physics. 533 



3. On the Occlusion of Hydrogen by Lead and other Metals. — In 

 order to explain certain physical phenomena of secondary battery 

 action, Newmam and Streintz have examined the absorption 

 of hydrogen by metals and especially lead. Two methods of 

 charging the metal with the gas were employed : (1) charging 

 electrolytically and (2) charging by passing the gas over or 

 through the fused metal. Previous experimenters had used the 

 former method ; but since the plates were subsequently exposed 

 to the air, the hydrogen was oxidized. The author therefore 

 washed his plates in the absence of air with air-free water and 

 dried them in pure carbon dioxide. But on igniting them only 

 a trace of hydrogen was obtained. In using the second method, 

 the metal was heated in pure hydrogen, the excess of hydrogen 

 was expelled by means of nitrogen, and the metal was again 

 heated in oxygen ; whereby the occluded hydrogen was burned 

 to water which was weighed. The following are the values ob- 

 tained, the numbers representing the volumes of hydrogen 

 absorbed by one volume of metal: Lead 0*15, 0-11 ; palladium 

 502-35 (at 450°); platinum sponge 29-95, 15-37, 12-13, 6'48; plati- 

 num black 49-30; gold 46*32, 37*31; silver 0*00; copper 4-81, 

 4-78; aluminum 2-72; iron 29-17, 9-38; nickel 16-85, 17*57 ; 

 cobalt 153*00, 59'31. In the case of platinum sponge, of iron, of 

 nickel and of cobalt, the successive values decrease with the 

 same specimen of metal; the power of occluding the hydrogen 

 diminishing with repeated use of the same sample. — Monatsb. 



f Chem., xii, 642; Ber. Berl. Chem. Ges., xxv, (Ref.) 187, 

 March, 1892. G. F. B. 



4. The Principles of Chemistry ; by D. Mendeleeff. Trans- 

 lated from the Russian (Fifth Edition), by George Kamensky. 

 Edited by A. J. Greenaway. 2 vols. Svo, pp. xvi, 611, vi, 487. 

 London and New York, 1891. (Longmans, Green & Co.). — The 

 first edition of this book, issued in 1870, marked an epoch in the 

 history of chemistry, since in it was enunciated for the first time 

 the periodic law of the elements, so inseparably connected with 

 the name of its author. In reproducing the fifth edition in Eng- 

 lish, a great service has been done for chemical science among 

 English-speaking people which cannot fail to produce a marked 

 effect. The book itself is remarkable in many ways. In the first 

 place, its treatment of the subject matter is profound and far- 

 reaching. The author says : "The desire to direct those thirst- 

 ing for truth to the pure source of the science of the forces 

 acting throughout nature forms the first and most important 

 aim of this book. The time has arrived when a knowledge 

 of physics and chemistry forms as important a part of education 

 as that of the classics did two centuries ago. In those days the 

 nations which excelled in classical learning stood foremost just as 

 now the most advanced are those which are superior in the 

 knowledge of the natural sciences." The object of the book is 

 "to acquaint the student not only with the methods of observa- 

 tion, the experimental facts and the laws of chemistry, but also 



