464 



NATURE 



[January 8, 1920 



out in the book before us. A brief enumeration 

 of the contents will give an idea of what the 

 authors have attempted. 



After a short historical outline and a considera- 

 tion of catalytic criteria, we are brought to the 

 subject of promoters. There is a brief discussion 

 of the possible mechanism of promoters, and it is 

 pointed out that the beneficial effect of several 

 promoters present simultaneously " may be due 

 to the greater range of temperature over which 

 at least one of the oxides is unstable or labile." 

 In connection with induced or mutual effects, 

 Liveing's views are given their just prominence. 



Chap. iii. contains valuable information of a 

 kind not usually met with in a text-book — i.e. such 

 points as space-velocity and space-time yield — 

 together with a short description of the authors' 

 apparatus for the quantitative measurement of 

 heterogeneous catalytic processes. 



In the succeeding chapter oxidation processes 

 are considered, viz. the manufacture of sulphuric 

 acid, salt cake, the oxidation of ammonia ta 

 nitric acid, the manufacture of chlorine, the oxida- 

 tion of sulphuretted hydrogen, the purification of 

 illuminating gas and gaseous fuels, surface com- 

 bustion, catalytic oxidation in the dye industry, 

 the drying of oils, and other processes. Inci- 

 dentally, the necessity of a sound knowledge of 

 the thermodynamics of physico-chemical processes 

 is made evident. 



Chaps. V. and vi. deal with the manufacture 

 of hydrogen and with processes of hydrogenation 

 and dehydrogenation. These include some of the 

 most recent and important developments of ap- 

 plied chemistry. The authors in these chapters, 

 as elsewhere in the book, have added greatly to 

 the interest and value of their work by useful 

 suggestions regarding the directions along which 

 further advances are likely to be made or are 

 most urgently required. (As a minor point one 

 might query the meaning of the data attributed 

 to Rittman on p. 217.) 



In chap. vii. we pass to a consideration of the 

 all-important problem of the fixation of nitrogen, 

 especially by the Haber process, which has 

 attracted so much attention recently in the Allied 

 countries, and upon which the authors write from 

 first-hand knowledge, though too briefly. 



After dealing with hydration and hydrolysis in 

 chap, viii., in which such subjects as synthetic 

 alcohol, the manufacture of glucose, and the 

 Twitchell process are dealt with, the authors 

 return in chap. ix. to reactions of the " Sabatier " 

 type in their account of dehydration processes, 

 consideration being given at the same time to 

 dehydrations in homogeneous systems. 



To a very large extent the preceding chapters 



NO. 2619, VOL. 104] 



are devoted to catalytic processes of technical im- 

 portance — actual or potential. In chap. x. our 

 attention is directed to a different aspect of the 

 field, namely, the r6\e of catalysis in organic 

 synthesis, in which such topics as the Grignard 

 reagent, the Friedel-Crafts reaction, haloge na- 

 tion, the aldol and benzoin condensations, 

 dynamic isomerism, racemisation, and muta-rota- 

 tion are discussed, on the whole, rather too briefly 

 perhaps. 



In chap. xi. ferment and enzyme action is taken 

 up. Here we find catalysis the dominant charac- 

 teristic, serving as the link between chemistry 

 on one hand, and physiology and bacteriology 

 on the other. This chapter is particularly good. 

 The authors acknowledge their indebtedness 

 to Prof. Bayliss for his criticism of the treatment 

 given. 



In the next chapter we are brought to the con- 

 sideration of yet another field — namely, catalysis 

 in electrochemistry, a subject in which catalysis 

 plays an important but, on the whole, little recog- 

 nised part. It is of the greatest value to have 

 this aspect emphasised. The problems dealt with 

 are : cathodic reduction, anodic oxidation, and 

 passivity. 



The concluding chapter is entitled "Catalysis 

 in Analytical Chemistry." It is a familiar subject 

 considered from a somewhat novel point of view. 

 The treatment is comprehensive and sufficiently 

 detailed to give the reader a true impression of 

 the role of catalysis in this fundamental branch 

 of chemical training and practice. 



The book is excellent. It is indispensable, in 

 fact, to everyone interested in chemical science 

 whether on the academic or on the applied side. 



VV. C. McC. L. 



THE NEGLECTED STUDY OF 

 PROBABILITIES. 

 Calcolo delle Probabilita. By Prof. Guido Castel- 

 nuovo. Pp. xxiii -t- 373. (Milano-Roma-Napoli : 

 Society Editrice Dante Alighieri di Albrighi, 

 Segati e C, 1919.) Price 20 lire. 



AMONG the sins of omission for which mathe- 

 maticians and teachers of mathematics 

 might be charged, there is probably none which 

 has so vitally affected our national welfare as the 

 neglect of the study of probabilities. Into every 

 event of ordinary life considerations of probability 

 enter in a greater or less degree, and for this 

 reason every boy or girl who has learnt to use 

 vulgar fractions ought to be taught to apply 

 them to simple games of chance, and in this way 

 to illustrate the rules for fractional addition, multi- 

 plication, and so forth. In default of this know- 

 ledge, millions of pounds are spent on postal 



