REVIEWS 165 



The Rare Earth Industry. By Sidney J. Johnstone, B.Sc. (Lond.) Imp. Inst. 

 London. [Pp. xii -+• 136, with 42 illustrations.] (London : Crosby Lock- 

 wood & Son, 191 5. Price 7s. 6d. net.) 



Industrial Nitrogen Compounds and Explosives. By Geoffrey Martin, 

 Ph.D., D.Sc, B.Sc, F.C.S., and William Barbour, M.A., B.Sc, F.I.C., 

 F.C.S. [Pp. viii + 125, with 39 illustrations.] (London : Crosby Lockwood 

 & Son, 191 5. Price 7s. 6d. net.) 



Chlorine and Chlorine Products. By Geoffrey Martin, Ph.D., D.Sc, B.Sc, 

 F.C.S. [Pp. viii + 100, with 46 illustrations.] (London : Crosby Lockwood 

 & Son, 191 5. Price 7s. 6d. net.) 



These three volumes constitute Numbers II, III, and IV respectively of a new 

 series of manuals of chemical technology from the editorial pen of Dr. Geoffrey 

 Martin. At the present time, more than ever, the utility of such a series of 

 manuals is very great. Even to-day our chemical literature shows by contrast 

 with that of other nations a decided paucity of reliable manuals and handbooks 

 dealing with the thousand and one processes in operation in chemical industry. 

 These manuals assist in some measure in remedying this deficiency, but there are 

 still large fields of chemical industry on which they do not touch. 



Dr. Martin has rightly called to his aid several of the younger experts in the 

 branches of industry concerned, and the subject matter of these manuals is 

 reasonably up-to-date. 



The volume on the rare-earth industry includes chapters on thorium, cerium, 

 titanium, zirconium, tantalum, niobium, tungsten, uranium, and vanadium, together 

 with a chapter on the manufacture of incandescent mantles, pyrophoric alloys, 

 and electrical glow lamps. The volume concludes with a section on the industry 

 of the radioactive substances contributed by Alexander S. Russell, M.A., D.Sc. 



The scope of the second volume on nitrogen compounds comprises treatment 

 on the manufacture, properties and industrial uses of nitric acid, nitrates, nitrites, 

 ammonia, including synthetic ammonia, ammonium salts, cyanides, cyanamide 

 and nitrous oxide, whilst the section on explosives covers gunpowders, amide 

 powders, nitro-glycerines, picric acid, T.N.T., ammonium nitrate, chlorate and 

 perchlorate explosives, fulminates, detonators, and smokeless powders. Observa- 

 tions are included on the testing of explosives, their composition and statistics 

 relative to the proprietary brands most commonly used. 



The volume on chlorine and its products iiicludes the manufacture of chlorine 

 by the Weldon and Deacon processes, the electrolytic processes, a chapter on 

 liquid chlorine, the manufacture of bleaching powder, hypochlorites, chlorates and 

 perchlorates, chapters on the manufacture of hydrochloric acid, the bromine 

 industry, the iodine industry, hydrofluoric acid, hydrofluorsilicic acid, and potas- 

 sium bromide. There is a concluding chapter on recent oxidising agents by 

 G. W. Clough, B.Sc, covering the peroxides of the alkali and alkaline-earth 

 metals, the persulphuric, perboric, and percarbonic acids and their salts. 



The manuals are well printed, and one of their most notable features is the 

 excellent method in which the subject matter is paragraphed out by the use of 

 several varieties of type. The drawings are good and show a sufficiency of detail, 

 and the authors are to be commended on the very frequent use of tabular synopses. 

 Another very important feature incorporated in these manuals is the prolific 

 references both to scientific and patent literature, and throughout the texts there 

 are extended descriptions of the manufacturing details involved in British and 

 foreign patents. 



