December i8, 1919] 



NATURE 



391 



its foundations, and the contemporary trend of its 

 development. 



The ignorance of the history of any science 

 could easily be remedied. Each head of a scien- 

 tific department should arrange for a historical 

 course in his subject. The interest aroused by 

 such an adequately prepared and well delivered 

 and illustrated historical course would more than 

 repay the time spent on it. 



The acquisition of a competent view of any 

 subject is more difficult, and especially in mathe- 

 matics, as is illustrated by Dr. Shaw's lectures. 

 No student of mathematics can be expected to be 

 familiar with all or even with the majority of the 

 branches of mathematics mentioned by Dr. Shaw. 

 The pass man would probably lay the book down 

 after reading the first chapter — if he gets thus far. 

 The honours student would perhaps go further, 

 particularly if his speciality is pure mathematics 

 and his reading has been ably directed by a 

 teacher familiar with modern mathematical ten- 

 dencies. Vet Dr. Shaw has dealt with his theme 

 in a particularly persuasive and very elementary 

 manner. 



The author considers the "speculative thinker " 

 who desires " to know the content of mathe- 

 matics," "to hunt for the central principle that 

 controls its evergreen growth," to explore "the 

 source of mathematical reality," and to discover 

 the "methods pursued in the field of investiga- 

 tion" and the "right of this Queen of all the 

 sciences to rule." These problems are dealt with in 

 a brief and clear exposition, which must bf. read in 

 order to be appreciated. It would be idle to 

 attempt a summary, as this would not convey 

 much to the uninitiated for whom the lectures 

 were written. Suffice it to say that in Dr. Shaw's 

 opinion there is no single principle of mathe- 

 matics, no single source of reality, no single 

 mathematical method. 



These lectures should be read and re-read by 

 all who desire to fathom the depths of the reality 

 of mathematics. They will be inspired to a view 

 of the subject different from the drab and utili- 

 tarian view so often prevalent in our colleges. 

 They will learn at least to give his due share of 

 recognition to the mathematician who "sits with 

 abstracted mien, his mental eye turned inward 

 upon some intricate construction of symbols and 

 formulae," and to respect, perhaps even to share, 

 his joy when he catches the flash of triumph. 



S. Brodetskv. 



OUR BOOKSHELF. 

 The Journal of the Institute of Metals. Vol. xxi. 

 Edited by G. Shaw Scott. Pp. xi + 5o8-f40 

 plates. (London : The Institute of Metals, 1919.) 

 315. 6d. net. 



Of the new volume of this important journal, no 

 fewer than 216 pages are occupied by the fourth 

 report to the Corrosion Committee by Drs. Hen- 

 gough and Hudson and the subsequent discussion. 

 NO. 2616, VOL. 104] 



The new report embodies the results of a very 

 large amount of experimental work, and is dis- 

 tinctly helpful in regard to the immediate problem 

 of extending the life of brass condenser tubes. A 

 large array of new facts bearing on the baffling 

 question of the mechanism of corrosion is also 

 included,' and illustrated by numerous plates. The 

 authors favour the view that direct oxidation takes 

 place without preceding electrolytic action.' As 

 Prof. Armstrong points out in the discussion, the 

 theory of corrosion is in a disappointingly back- 

 ward state, and no satisfactory explanation has 

 yet been given of some of the most familiar facts. 

 The report is a valuable one, and fully justifies 

 the continuance of the work of the committee. 



Messrs. Hanson and Archbutt contribute a most 

 useful account of their methods of polishing and 

 etching aluminium and its light alloys, and of 

 identifying the constituents, a task which has pre- 

 sented difficulties to most metallographers. 

 Another paper from the same laboratory, by Dr. 

 Rosenhain and Mr. Hanson, records the proper- 

 ties of some copper alloys which were devised for 

 war purposes, and incidentally describes a con- 

 venient method of obtaining clean castings by 

 working under pressure. A note by Lt.-Col. 

 Jenkin on the metallurgical information required 

 by engineers is followed by a lively discussion, 

 the conclusion being reached that the determina- 

 tion of true physical constants is lil^ely to super- 

 sede many of the present empirical tests. There 

 are two papers on the effect of cold work on 

 metals, and an interesting discussion on the rela- 

 tion of science to the industry of the non-ferrous 

 metals, in which the respective views of scientific 

 workers and manufacturers are well and clearly 

 expressed. The volume concludes with the usual 

 abstracts of metallurgical literature. 



C. H. D. 



Golden Days from the Fishing-Log of a Painter 

 in Brittany. By Romilly I'"edden. Pp. xviii-)- 

 233. (London : A. and C. Black, Ltd., 1919.) 

 Price "js. 6d. net. 



Hkke is a book full of quiet charm and humour, 

 written by one who is evidently not only an artist 

 and a sportsman, but also a true lover and ob- 

 server of Nature and her ways. The angler will 

 be fascinated by the vivid descriptions of trout- 

 and salmon-fishing in Brittany. There are no 

 improbable fisherman's yarns to invite his scep- 

 ticism, but their place is taken by some delightful 

 stories of saints and miracles drawn from the 

 Breton folk-lore, so that the book appeals quite 

 as much to the general reader as to the piscatorial 

 fraternity. It is a pleasant narrative, well suited 

 to while away a winter evening at the fireside 

 and to conjure up visions of sunlit meadows, fra- 

 grant pinewoods, and murmuring streams, though 

 tinged, alas ! by that vein of sadness which must 

 colour the day-dreams of all of us at the present 

 time, and especially of those who, like the author, 

 have witnessed at close quarters the tragedy of 

 the last few years. 



