428 • REVIEW. 



While special problems must occasionaUy be encountered it is possible 

 to devise a general scheme of analysis which will prove adequate for the 

 examination of the great majority of explosives. None of the general 

 methods as yet published give general satisfaction in actual practice. 



A few of the omissions noted, either of work appearing since the 

 writing of the book or purposely not mentioned are : 



Pages 267 and 270. Eetene, Bucher, J. Am. Clem. Soc. (1910), 32, 

 374. Page 293, the work of Kohn and Fryer and J. Walter, concerning 

 the coloration of phenol is still quoted as authentic. (See This Journal, 

 Sec. A (1908) 3, 361 and (1909), 4, 133.) Page 340, Willstatter and 

 Majima's work is not mentioned in connection with the estimation of 

 quinone, Ber. 43, 1171. 



Few typographical errors are noted and the printing and type are 

 excellent. 



H. D. G. 

 W. C. H. 



Allen's Commercial Organic Analysis. Volume IV. Edited by Henry Leffmann 

 and W. A. Davis. 4th ed. Cloth, pp. x+466. Price $5 net. Philadelphia, P. 

 Blakiston's Son & Co. 1911. 



This volume is composed of the following divisions: (1) Eesins, by 

 M. Bennett Blackler, 103 pages; (2) India Eubber, Kubber Substitutes, 

 and Gutta-percha, by E. W. Lewis, 57 pages; Hydrocarbons of Essential 

 Oils, by T. Martin Lowry, 25 pages; Ketones of Essential Oils, by T. 

 Martin Lowry, 28 pages; Volatile or Essential Oils, by E. G. Parry, 85 

 pages; Special Characteristics of Essential Oils by Henry Leffmann and 

 Charles H. La Wall, 128 pages; Tables of Essential Oils, 30 pages; and 

 an Index, 4 pages. 



The volume is admirably arranged, and contains much new matter 

 not found in the older editions. It will unquestionably prove of great 

 value as a reference book for analysts. 



The treatment of Manila copal has not been brought up to date and 

 no reference is made to the investigations on that subject can-ied out 

 at the laboratory of the Bureau of Science which have not confirmed 

 in every respect the earlier work of Tschirch and Koch. 



The treatment of certain other subjects is also, perhaps, not as com- 

 plete as might be desired. For example, only one method, namely, the 

 iso-bornyl acetate method, is given for the passage from pinene hydro- 

 chloride to camphene, in the preparation of artificial camphor, whereas 

 we understand that several methods, equally as good are now employed. 



However, in general this volume offers but little chance for adverse 

 criticism and will be found to attain the high standard of the previous 

 volumes of the same edition. 



W. C. H. 



