394 



NATURE 



[December 9, 1915 



informed student in answer to an examination 

 question. Of more imf)ortance is the chapter on 

 bleaching powder and hypochlorites, and the de- 

 scription of recent methods of electrolytic bleach- 

 ing- is of special value. There can be no question 

 that these methods are destined to effect a funda- 

 mental change in our textile industries. Already 

 they have displaced a considerable amount of 

 bleaching powder, and their application is rapidly 

 extending, especially on the Continent, where the 

 plants of Schuckert, Kellner, and Oettel are 

 largely employed. 



The chapters on the manufacture of hydrochloric 

 acid, bromine, and iodine present no special fea- 

 tures of novelty. Until the outbreak of the war 

 practically the whole of the European supply of 

 bromine came from the Stassfurt deposits, but 

 large quantities are now finding their way into 

 commerce from America. The mineral springs 

 of Ohio contain nearly four times the amount of 

 magnesium bromide that is present in the mother 

 liquors obtained from carnallite. The account of 

 the iodine industry is mainly abstracted from 

 Prof. Henderson's article on that subject in 

 Thorpe's "Dictionary of Applied Chemistry." 

 The short chapter on hydrofluoric acid is of in- 

 terest as showing the increasing commercial im- 

 portance of this substance, not only in etching 

 glass, but in the purification of graphite from 

 silica, in dyeing, and in the spirit and brewing in- 

 dustries. 



The final chapter on peroxides and peracids 

 gives a short description of the more technically 

 important peroxides of the alkalis and alkaline 

 earths, which come into commerce as "oxone," 

 "oxylith," etc., and the various perhydrols, in- 

 cluding hydrogen peroxide. The account of the 

 peracids and their salts deals with the so-called per- 

 sulphuric acid and permonosulphuric acid (Caro's 

 acid) and the persulphates of the alkalis; sodium 

 perborate (used in certain " dry " soaps and as a 

 washing and bleaching agent); and the alkaline 

 percarbonates. These substances have at present 

 only a slight technical importance, but their use 

 is gradually extending. 



OIL SEEDS AND THEIR PRODUCTS. 

 The War and New British Industries. Imperial 

 Institute Monographs. Oil Seeds and Feeding 

 Cakes, with a Preface by Dr. W. R. Dunstan. 

 Pp. xxiii + ii2. (London : John Murray, 191 5.) 

 Price 2s. 6d. net. 



IF the war has no other results, it is at least 

 compelling us to examine our affairs in such 

 detail as we have never before attempted, and 

 the examination has brought to light all sorts of 

 NO. 2406, VOL. 96] 



curious facts about industries that we ought to 

 have started and did not, and products that we 

 ought to have made for ourselves but purchased 

 instead. Who, for example, would have supposed 

 that the palm-kernel oil used in this country, and 

 grown in British West Africa, had to be pressed 

 out in Germany? It is not to be imagined that 

 the British mills were unequal to the task; but 

 somehow they did not do it, and consequently the 

 outbreak of war threatened West Africa rather 

 seriously. Fortunately, Sir Owen Philipps, the 

 chairman of the West African Section of the 

 London Chamber of Commerce, took the matter 

 up, and equally fortunately the Imperial Institute 

 energetically turned its attention to the whole 

 problem of oil seeds affected by the war. The 

 Institute has already published some important 

 reports on the subject, which are now embodied 

 in the book under review. 



The substances dealt with are copra, palm 

 kernels," ground nuts, sesame seed, and mowra 

 seed. All these are produced largely in the 

 British Empire; most of them were sent in great 

 quantities to Germany and Austria, where the oil 

 was expressed, the residues made into feeding 

 cakes for stock (except in the case of sesame and 

 mowra seed), and both these commodities were 

 re-exported to the countries needing them. 



The fact only wants stating to compel atten- 

 tion, and Prof. Dunstan has wisely contented' 

 himself with a recital of economic uses of the oils 

 and residues, the amounts available, the markets 

 to which the seeds have hitherto gone, and the 

 possibilities of extending the industry. No more 

 eloquent testimony could possibly be adduced to 

 prove the need for establishing this industry in 

 our own country at the earliest opportunity. 



The utilisation of oil seeds presupposes two 

 distinct conditions. There must be a demand for 

 the oil, and it must be possible to utilise the 

 residual "cake " left after the extraction. Usually 

 the oil finds application without difficulty. The 

 higher qualities are used for margarine, vegetable 

 butter, olive-oil substitutes, etc. ; lower grades 

 for soap-making, lubricating, and illuminating 

 purposes. The residual cake presents a more 

 difficult problem. On the Continent, the copra, 

 palm-nut, and ground-nut cakes are used as cattle 

 food, while the sesame and mowra are unsuitable, 

 and have to find other applications; but in this 

 country the farmer is so well satisfied with linseed 

 and cotton-seed cakes that he sees no reason why 

 he should take up any others. It is here that the 

 crux of the situation lies; the farmer cannot be 

 expected to purchase a product solely for the con- 

 venience of the oil mills, nor is it any use trying 

 to badger him into doing so by sending him 



