Chemistry and Physics. 689 



3. A New Reaction for Osmium. — M. L. Tschugaepf has 

 found that when a solution containing osmium in the condition of 

 tetroxide, 0s0 4 , or of any chlorosmiate, for example, K 2 OsCl c , 

 is heated for a few minutes with thiourea in excess and with a 

 few drops of hydrochloric acid, the liquid becomes bright red or 

 pink, according to the concentration of the osmium compound 

 present. This reaction is very characteristic and permits the 

 detection of osmium in a solution of 1 to 100,000. The red com- 

 pound of osmium formed in this reaction, when crystallized, has 

 a composition corresponding to the formula Os(N 2 H 4 CS) 6 Cl 3 . 

 H 2 0. Consequently it is a new base analogous to the luteo-salts 

 of certain other metals, such as Cr(NH 3 ) 6 X 3 , Co(NH 3 ) 6 X 3 

 Rh(NH 3 ) G X 3 , and Ir(NH 3 ) 6 X 3 .— Comptes Rendus, 167, 235. 



H. L. W. 



4. Chemical Combinations among Metals; by Dr. Michele 

 Giua and Dr. Clara Giua-Lollini. Translated by Gilbert 

 Wooding Robinson. 8vo, pp. 341. Philadelphia, 1918 (P. 

 Blakiston's Son & Co.). — This work gives an excellent account 

 of metallic combinations from a chemical point of view. Many 

 equilibrium diagrams based upon thermal analysis are given, 

 showing the melting-points of alloys and the compounds, eutectics 

 and solid solutions produced in them, and this subject is very 

 fully explained. The microscopic side of the study of alloys is 

 not treated in this book, but it furnishes an excellent introduction 

 to the practical study of metallography. 



In its theoretical discussion of the subject the book emphasizes 

 the importance of the phase rule of Willard Gibbs in connection 

 with the study of alloys, and it may be noticed that several of 

 the equilibrium diagrams are based upon the work of Professor 

 Mathewson of Yale. h. l. w. 



5. The Zinc Industry; by Ernest A. Smith. 8vo, pp. 223. 

 London, 1918 (Longmans, Green & Co.). — This is one of the 

 extremely important and useful monographs on industrial chem- 

 istry now being issued by the same publishers under the editor- 

 ship of Sir Edward Thorpe. The work under consideration gives 

 a general survey of the development and present condition of the 

 zinc industry. Many interesting statistics are presented, most of 

 which do not apply to the period of the present war, but the effect 

 of the war upon the industry is extensively discussed, and the 

 resulting great development of zinc production in the United 

 Statesns mentioned. The sources of zinc ores, zinc smelting and 

 other methods of production, the properties of the metal, its 

 industrial applications, its alloys, etc., are discussed in a very 

 satisfactory way. h. l. w. 



6. Stoichiomctry ; by Sydney Young. 8vo, pp. 363. Lon- 

 don, 1918 (Longmans, Green & Co.). — This is one of an extensive 

 series of text books on physical chemistry, edited by the late Sir 

 William Ramsay. The first edition of the book appeared in 1907, 



