REVIEWS 497 



The Revolutions of Civilisation. By W. M. Flinders Petrie. [Pp. 131. 

 Illustrated.] (Harper's Library of Living Thought : Harper & Brothers, 

 London and New York, 191 1. Price 2s. 6<Y.) 



This is a pearl of price among books — one that should be pondered over by every 

 thinking member of the community, as it carries a message, of vital importance to 

 our race, conveyed with rare skill and a most unusual wealth of indisputable 

 illustration. Prof. Petrie traces the rise and fall of no less than eight successive 

 Egyptian civilisations and also of European civilisations, taking sculpture as the 

 definite test of rise and fall. His conclusions are pessimistic in so far as they have 

 any bearing on the question of our own future. The book consists largely of 

 illustrations, many of which are most beautiful. No name is attached to most of 

 the plates but those who are aware of the authors unrivalled skill as a photo- 

 grapher of Egyptian remains will recognise them as Prof. Petrie's handiwork. 



The Chemistry and Testing of Cement. By Cecil H. Desch, B.Sc, Ph.D. 

 [Pp. xi + 267.] (London : Edward Arnold, 191 1. Price 10^. 6d.) 



The author of this book has given in a compendious form an account of the 

 chemistry and methods of testing — physical, chemical and mechanical — calcareous 

 cements, appropriately leaving out of consideration those minor cementing 

 materials, such as glue, casein preparations and the like, which have little in 

 common with cements used for engineering and constructional purposes. 



He includes plaster of Paris, ordinary lime mortar, hydraulic limes, Roman 

 cement and the various cements made from blast furnace slag alone or with lime 

 but properly devotes his chief attention to Portland cement as the most important 

 member of its class. Besides the cements themselves, their raw materials are 

 spoken of and a description is given of the usual methods of manufacture, whilst 

 some space is allotted to concrete, including the reinforced material and the 

 resistance of cement and concrete to the destructive influence of such agencies 

 as sea-water, frost and certain classes of sewage. The book is illustrated by 

 plates, some of which were prepared from photomicrographs ; it also contains a 

 number of useful tables giving numerical data of the mechanical and physical 

 properties of cements. 



It will be seen that the authors scheme is comprehensive and we may say at 

 once that, although the book is of very modest dimensions, the ground has been 

 well covered and the object in view has been satisfactorily achieved. The vexed 

 question of the chemistry of cement has been handled with conspicuous ability, 

 the doubtful or erroneous statements which have long disfigured this branch 

 of work being rejected and the latest and best founded theories retained and 

 explained. Although free from any partisan tendency, the author makes it 

 abundantly plain that he holds the views of the most modern school of cement 

 chemistry ; on the balance of evidence we agree with his conclusions. In like 

 manner, in the matter of testing he does not hesitate to condemn such obsolete 

 methods as the determination of the weight per bushel and supports without 

 reservation those later and better modes of examination, some of which, like the 

 Le Chatelier test, have had to make their way against opposition not always 

 disinterested. His remarks on the desirability of ensuring that concrete should 

 be dense and as free as possible from voids, the spaces to be filled by cement 

 being ascertained by actual measurement instead of left to chance by the adoption 

 of some casual proportions without regard to the particular character of the 



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