44 



NATURE 



[September 9, 1920 



that linseed oil can be blown in five or six hours, 

 whereas to obtain a suitable product, in our ex- 

 perience, eighteen to twenty hours are necessary. 

 Also in the manufacture of linoleum cements 

 he mentions an amount of kauri gum which is 

 far in excess of that required. His assumption 

 that in the blowing process (Wood and Bedford, 

 and Walton) " superoxidised oil " is formed has 

 not as yet been proved (see Ingle and Wood- 

 mansey, J.S.C.I., 1919, p. loi). Otherwise the 

 brief description of the linoleum industry is good. 



In discussing the oils used in the cloth trade, 

 while the preparation of distilled oleines, etc., is 

 well treated, the testing of them with regard to 

 their application is too brief. We do not find any 

 reference to the Mackey oil tester, and little men- 

 tion of the danger of spontaneous ignition or other 

 fire risks. 



The analytical chapter is all too brief, though 

 for the most part well done. The present writer 

 has shown (J.S.C.I., 1902, p. 587) that Hubl's 

 solution should be used fresh, and not after 

 twenty-four hours' mixing, as Dr. Martin, copy- 

 ing Dr. Lewkowitsch, states. With regard to the 

 preparation of Wijs's solution, Dr. Martin includes 

 the method from iodine trichloride, a product of 

 doubtful purity, and in this he follows the recom- 

 mendation of the Government Committee of 

 Analysts (Ministry of Food), but he also gives in 

 the chapter the more trustworthy method by the 

 saturation of glacial acetic acid solution of iodine 

 with dry chlorine. Also one misses the details of 

 the valuable hexabromide test. 



W^ith regard to the edible qualities of hydrogen- 

 ated oils as compared with natural fats, such as 

 butter and lard, it may be pointed out that the 

 assumption of a continuous carbon chain in all 

 the fatty acids has not yet been proved. It is 

 probable that some of the unsaturated oils con- 

 tain "branched chains " (Verzeigte Ketten), and 

 so in hydrogenation isomeric stearic acids may 

 be formed, and these may .have quite different 

 digestibility. Hence it does not follow that a 

 stearine produced by hydrogenation would have 

 the same food value as a natural fat. 



The author reprints reports of the Government 

 Committee of Analysts (Oils and Fats Branch, 

 Ministry of Food) which -we consider so inade- 

 quate that it is surprising that Dr. Martin gives 

 them space. 



On the whole, the work should prove of great 

 assistance to the student of the industrial develop- 

 ments of the oil trade, but to the chemically 

 minded it does not go far enough into the dis- 

 cussion of the application of scientific principles 

 and tests to the industry. Harry Ingle. 



NO. 2654, VOL. 106] 



Science in History. 



Transactions of the Royal Historical Society. 

 Fourth Series. Vol. xi. Pp. v + 247. 

 (London : Royal Historical Society, 1919.) 



TO scientific readers the most important com- 

 munication in this volume is that by 

 Sir Richard Gregory, entitled " Science in the 

 History of Civilisation." There are, the author 

 tells us, two methods of approaching the history 

 of science — that of the specialist, who regards it 

 purely as growth of the knowledge of material 

 objects and phenomena in the course of time ; and 

 that of the historian of human culture, who dwells 

 on its influence upon social and economic con- 

 ditions. The object of this paper is to plead for 

 a closer co-ordination of these separate points of 

 view in works of general history. This has been 

 attempted to some extent by Voltaire, Buckle, and 

 Lecky, and in more recent times by Mr. and Mrs. 

 Whetham and by Mr. F. S. Marvin ; but some 

 modern speculations have served only to darken 

 knowledge. The late Mr. B. Kidd traced the 

 cause of the evolution of society to the continu- 

 ous action of religious beliefs, but Dr. Russel 

 Wallace pointed out that, the doctrine of pro- 

 gressive ethical impulse does not explain how the 

 rude struggles of 2000 years ending in the six- 

 teenth century could have tended to increase and 

 develop the altruistic and ethical sentiments of 

 early races in their struggle for existence. 



The true age of science dates from the era of 

 experimental investigation, advocated by Roger 

 Bacon and advanced by Galileo and the men of his 

 age. It is the scientific scepticism thus created 

 which is responsible for the growth of knowledge 

 and its effects to which all material advance is to be 

 attributed. The question for the future is how to 

 use rightly the power which science gives to 

 modern man ; not to teach it as a jumble of iso- 

 lated facts and theories, but in the history of its 

 development from the earliest times. The neces- 

 sity of paying increased attention to the history 

 of science has been urged by Sir J. J. Thomson's 

 committee on the position of natural science in 

 the educational system of Great Britain ; and on 

 the research side a group of students working 

 with Dr. C. Singer at Oxford has produced the 

 first volume of " Studies in the History and 

 Method of Science," while a second is in the press, 

 to be the basis, it is hoped, of a comprehensive 

 "History of Science," on lines similar to those 

 of the "Cambridge Modern History." This new 

 movement is ably advocated in the paper under 

 notice. C. 



