July 29, 1922] 



NA TURE 



! 43 



rivatives of purin — the mother substance of uric acid — 

 and later of the proteins, thereby opening the door 

 to almost a new branch of organic and physiological 

 chemistry. Even in 1908. when he compiled the first 

 set of reprints of his sugar work, he expressed the fear 

 that this sensitiveness to phenylhydrazine would 

 prevent him from taking any further active part in 

 developing the chemistry of the sugars. Fortunately 

 for posterity the old love proved too strong, and he 

 returned again and again to the fray, the result being 

 that forty-six additional essays chronicle the work 

 achieved. 



The writer had the good fortune to come under 

 Fischer's tuition at the time of the opening of the new 

 chemical laboratories in the Hessische Strasse in Berlin, 

 and to be intimately associated with him during nearly 

 three years, carrying out sugar inquiry under his 

 inspiration, although at this time all other workers in 

 the laboratory were busily engaged in the early stages 

 of the great investigation on amino acids and proteins. 

 Viewed from the perspective of twenty years later, it 

 would seem that Fischer was already at that time a 

 tired man, feeling both the strain of the work involved 

 in obtaining and designing the new laboratory and 

 the distraction caused by the heavy burden of official 

 duties, which he never relished but could not avoid. 

 Hoesch now throws much light on the events behind 

 the scenes just before this period, as the provision of 

 the new laboratory, made the first condition of 

 Fischer's going from Wurzburg to Berlin, eventuallv 

 took seven and a half years. I lis account includes the 

 statement that at one time Fischer even seriously 

 considered leaving Berlin and going to Bonn. 



Apparently from the time he came to Berlin, as 

 successor to Hoffmann, Fischer lived only for his work, 

 and withdrew more and more within himself as the 

 years passed. A widower, with his sons still young, 

 he had no one to draw him out of himself in private 

 life ; he seemed to lose the power of unbending to his 

 associates, although he was worshipped by his labora- 

 tory companions. 



Having achieved the first synthesis of a natural 

 sugar, glucose, Fischer's greatest ambition was to 

 make ordinary cane sugar in the laboratory, and in 

 1900 this problem was again attacked with all the re- 

 sources of the new laboratory. At first some measure of 

 success was attained, as complex sugars (disaccharides) 

 were obtained, identical or isomeric with some of the 

 natural materials. The problem of the synthesis of 

 cane sugar itself defied solution, however, and a 

 measure of the difficulty of the subject is afforded by 

 the fact that to-day, twenty years later, we are appar- 

 ently no nearer success, in spite of the great progress 

 made in other sections of carbohydrate chemistry. 

 NO. 2752, VOL. I IO] 



The difficulties of synthesising natural and artificial 

 glucosides were fully mastered, nearly half the papers 

 published since 1908 dealing with this field of inquiry. 

 These include the recognition of a third form of methyl- 

 glucoside, the existence of which was concurrently 

 demonstrated by Irvine in this country. This form, 

 which apparently contains a y-oxide ring, is highly 

 active, and according to later work of Haworth, it may 

 be the form in which the fructose molecule is present 

 in cane sugar, for which Haworth accordingly suggested 

 a new formula. The writer is not aware that Fischer 

 expressed his views anywhere as to the correctness of 

 Haworth's work ; it cannot but have inspired him to 

 renewed experimental effort to effect the much-desired 

 synthesis. 



In a dozen of the later papers are described results 

 of the investigation of the acyl derivatives of the 

 sugars, while a like number deal with mutations 

 within the sugar molecule leading to the formation of 

 substances such as glucal. The results serve to show 

 that the chemist has still much to learn about this 

 remarkable group ; but they are too complex to be 

 considered here. 



Fischer's early work on enzymes is an acknowledged 

 classic contribution to biological science. He returns 

 to the subject in the last paper in this collection, dated 

 July 14, 1919, a day before his death : this contains 

 additional data for the discussion of the all-important 

 question of the influence of the structure of /i-glucosides 

 on the activity of emulsin. It is written in Fischer's 

 usual simple style — he used to dictate his papers while 

 moving about the room in a very restless state — and 

 shows how to the very end he retained his clarity of 

 mind. A future generation alone can decide whether 

 he should not be regarded as the greatest organic 

 chemist the world has yet known. 



E. F. Armstrong. 



American General and Economic Geology. 



A Text-book of Geology. By Prof. A. W. Grabau. In 

 two parts. Part I. : General Geology. Pp. xviii + 

 864. Part II. : Historical Geology. Pp. viii + 976. 

 (London : G. G. Harrap and Co., Ltd., n.d.) 645. 

 net, two vols. 



The Economic Aspects of Geology. By C. K. Leith . 

 Pp. xvi + 457. (London: Constable and Co., Ltd., 

 1922.) lis. 



ROF. AMADEUS GRABAU, who is now 

 professor of paleontology in the University 

 of Peking and palaeontologist to the Geological Survey 

 of China, is the author of several excellent American 

 geological text-books, and his new " Text-book of 



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