494 



NATURE 



[January 15, 1920 



staff of a hospital, who alone would perform the 

 operation, with, in many cases, the work of a 

 newly qualified house-surgeon. 



In many respects the book fills a gap in medical 

 literature, and will be of great help not only 

 to the general body of medical workers, but also 

 more particularly to those who are specially en- 

 gaged in this line of work. 



TRE OIL-HARDENING INDUSTRY. 

 The Hydro genation of Oils : Catalysers and Cata- 

 lysis and the Generation of Hydrogen and Oxy- 

 gen. By Carleton Ellis. Second edition, thor- 

 oughly revised and enlarged. Pp. xvii + 767. 

 (London : Constable and Co., Ltd., 1919.) Price 

 36X. net. 

 " TTAT hardening" and " hydrogenation " are 

 Jr' the trade terms for the chemical process of 

 saturating liquid oils with hydrogen in presence of 

 finely divided nickel. These operations, which a 

 few years ago were conducted with great secrecy, 

 are now regarded as more or less normal in every 

 soap factory, and the usual extensive literature has 

 grown up to describe them. Much of this is natur- 

 ally diffuse, and much again inaccurate, so that 

 there was ample room for an authoritative book 

 on the subject. This was provided by Carleton 

 Ellis in 1914, but since its publication the strides 

 made in the oil-hardening industry have been very 

 great, making a second edition, which endeavours 

 to bring the subject up to date and offers sug- 

 gestions of future possibilities, more than wel- 

 come. 



The book has now swollen to 700 pages, and is 

 replete with information ; it is essentially a work 

 of reference for the expert, and necessarily filled 

 with far too much detail to be easily readable by 

 chemists in general. 



The first edition, reviewed in Nature of May 

 20, 1915, deservedly established a very high repu- 

 tation for the author, which will be enhanced by 

 the new volume. Doubtless this contains the 

 inevitable printer's errors and minor inaccuracies, 

 but we are less concerned to seek for these than 

 to thank the author for his unselfish labours on 

 behalf of his future readers. 



The plan followed is first to discuss the methods 

 of hydrogenation in detail, much of the plant being 

 illustrated and full account taken of the patent 

 literature. The next section, occupying more than 

 150 pages, is devoted to the many aspects of 

 the subject of the activity of the base metals as 

 catalysers. The vexed question as to whether 

 metallic nickel or nickel oxide is the active agent 

 is fully discussed in so far that the opinions and 

 experiments of the protagonists are given at 

 NO. 2620, VOL. 104] 



length, but the author refrains here, as elsewhere 

 in the book, from giving the reader any lead as to 

 which theory is the more probable. There follows 

 an important chapter on the analytical constants 

 of hydrogenated oils. 



Although first introduced for providing hard 

 fats for soap-making, hydrogenation has proved 

 equally applicable to edible oils. As fats natur- 

 ally fetch a higher price as foodstuffs than as 

 soap-making materials, their technical production 

 in the edible form' has been extensively studied. 

 Reference is made to other uses and properties of 

 hardened oils. 



The hardening process has also been extended 

 to petroleum, where many new problems arise, 

 which are now described. Not only does crude 

 petroleum contain unsaturated constituents, but 

 these are also formed in some quantity during the 

 cracking processes. 



The first stage in any hardening process is the 

 prodyction of hydrogen of the necessary purity and 

 cheapness. A variety of methods for making 

 hydrogen are in practical operation, and still more 

 have been suggested, so that it is not surprising 

 that fully a quarter of the book is devoted to the 

 description of these. In the future the cheap pro- 

 duction of hydrogen will play a great part in the 

 formation of ammonia from the air, and through 

 ammonia of nitrates, and so influence increased 

 soil fertility. 



The fat-hardening industry has had more than 

 its share of patent litigation, famous cases having 

 been fought both in this country and more recently 

 in America. The report of the English case is 

 given, substantially as published in the British 

 official journal, in an appendix, whilst the case of 

 The Procter and Gamble Co. v. The Berlin Mills 

 Co. is reprinted in such detail as to occupy eighty 

 pages. E. F. A. 



POLITICAL SCIENCE. 

 A New Chapter in the Science of Government. By 

 Benchara Branford. Pp. xlviii-H 190. (London: 

 Chatto and Windus, 1919.) Price 55. net. 



THIS book is not perhaps likely to become 

 popular. It is defective both in shape and in 

 style ; nor is the language of the author free from 

 eccentricity and even ambiguity. It is possible that 

 some reason may be urged for such phrases as 

 " Britamerindian Commonweal " or " Britamer- 

 iiidian re-orientation of politics," in which the 

 author seems to take an especial pleasure. But 

 phrases like " a spiritual instrument of explora- 

 tion on the rough politico-economic terra incog- 

 nita," or "feeling of communitary responsi- 

 bility," or "an extension of our synoptical cate- 



