804 



NA JURE 



[Dkckmber i 6, 1922 



the large number of persons who have been privileged 

 to collaborate with Dr. Haldane. To that company 

 the book will mean something more than a mere re- 

 capitulation of his work or a history of the development 

 and philosophic position, or a commentary on the action 

 and reaction of abstract science on industrial research ; 

 it will mean something a little sacred, but something 

 which one of them, at all events, finds some difficulty 

 in putting into words. Joseph Barcroft. 



Our Bookshelf. 



An Introduction to Sedimentary Petrography : With 

 special reference to loose Detrital Deposits and their 

 Correlation by Petrographic Methods. By Henrv B. 

 Milner. Pp. 125. (London : T. Murby and Co., 

 1922.) 8s. 6d. net. 



This attractive little book deals mainly with loose 

 detrital deposits and their correlation by petrographic 

 methods. The first chapter gives an account of 

 sampling, treatment, and methods of examination in 

 about a dozen pages. The next chapter (56 pages) 

 deals with detrital minerals and is illustrated by 

 numerous plates showing the shapes and appearances 

 of loose grains and crystals. Following this are two 

 chapters in which a courageous effort is made to show 

 the value of the evidence provided by detrital minerals 

 as a means of stratigraphical correlation, and as an 

 aid in palaeogeographical studies. A useful biblio- 

 graphy, a table showing the distribution of detrital 

 minerals in British strata, and an index are included. 



It is not easy to share Mr. Milner's confidence in 

 the inferences he draws from the evidence provided 

 by the mineral composition of sediments. Such 

 evidence is rather unsafe as a basis of stratigrapl ical 

 correlation, owing to the rarity and local significance 

 of instances in which detrital minerals are derived from 

 what he calls "homogeneous distributive provinces." 

 The difficulty of generalising safely on the gem 

 detritus is illustrated very forcefully by Mr. Milner's 

 statement that a garnet-staurolite-kyanite suite 

 derivation from a definite thermo-metamorphic province, 

 while a sphene-apatite-zircon assemblage is indicative 

 of acid or intermediate rock-types as sources of supply, 

 whereas an ilmenite-anatase-rutile-brookite association 

 points to derivation from basic or ultrabasic rock-types. 



These are. to say the least, highly controversial state- 

 ments, but they tend to make the subject interesting 

 and to stimulate further work ; for. as Mr. Milner very 

 properly remarks, the aim of science should be not 

 merely to collect facts, but to explain them, and to 

 put them to service in the solution ol larger problems. 

 The difficulty in this particular case is that the facts 

 available are as yet scanty and very local in their 

 significance. Much patient fact-collecting remains to 

 be done before it can be ascertained whether any given 

 system or series has definite characteristics as regards 

 the nature and mineral composition of its detritus, 

 and what those characteristics are. Xot until this wi irk 

 has been done will it be safe to assert that the evidence 

 provided by detrital minerals is useful in any sub- 

 stantial way as a basis of stratigraphical correlation. 



T. C. 



Universal Problems. By H. Jamyn Brooks. Pp.123. 

 (Braintree. Essex : The Author, The Limes. Shalford, 

 1922.) 



Review by quotation is not usually desirable, but with 

 books of the class to which Mr. Brooks's belongs it is 

 the only possible method. It will suffice to quote at 

 random three of the eight " hypotheses on which the 

 theories discussed in the work are founded." 



" 1. Every element, whether it be chemical, physical 

 or mental, is distributed in unbroken unity throughout 

 universal space." 



"5. The mode of progression of the physical forces 

 through matter and space is by communicated com- 

 bustion, as is illustrated by the ignition of a train of 

 gunpowder." 



" 7. Energy is the force which becomes manifest 

 through expansion and contraction." 



At first we are inclined to be amused, but really 

 such books are tragic, not comic. For Mr. Brooks 

 lacks neither intelligence nor enthusiasm. He has 

 read enormously, and he has actually printed with his 

 own hands the little book in which his views are 

 presented. If only that intelligence and enthusiasm 

 had been combined with the desire and the capacity 

 to study science seriously ! If only he had given to a 

 few elementary text-books and a short course of 

 laboratory work the time and application lie has given 

 to encyclopaedia articles and " popular " treatises ! 

 Faced with such results as this, we are forced to ask 

 ourselves whether the " popularisation " of science is 

 all nr mainly gain. Has Prof. Eddington. for example, 

 — his book is quoted more frequently than any other — 

 done good to science by arousing the interest of un- 

 trained readers, or harm by encouraging the delusion 

 that they can really understand ? X. R. C. 



Mechanical Testing: A Treatise in Two Volumes. By 

 R. G. Batson and J. H. Hyde. (Directly-Useful 

 Technical Series.) Vol. 1 : Testing of Materials of 

 Construction. Pp. xiii + 413. (London: Chapman 

 and Hall. Ltd., 1922.) 215. net. 

 The contents of this volume deal with the testing of 

 materials of construction ; the testing of apparatus. 

 machines, and structures will be included in the second 

 volume. The authors have had extensive experience 

 in the National Physical Laboratory, and this is re- 

 flected in their book. A large number of engineers in 

 this country are now alive to the importance of con- 

 tinually testing the materials they employ, and to such 

 the volume will be welcome on account of the informa- 

 tion it contains regarding modern methods of testing. 

 The student will also find the book useful, since no 

 college laboratory contains all the apparatus described, 

 and text-books on materials usually have only brief 

 sections on the apparatus employed in testing. The 

 greater part of the volume is devoted to the testing 

 of metals ; besides the ordinary simple commercial 

 tests, we find chapters on the repetition of stress, 

 combined stresses, hardness testing, impact testing, 

 and the effects of temperature. The book closes with 

 chapters on the tests of timber, stone, brick, concrete, 

 road materials, limes, and cements. Sufficient informa- 

 tion is given regarding the results of methods of test- 

 ing to enable the experimenter to compare his own 

 results with average values for trustworthv materials. 



NO. 2772, VOL. I to] 



