152 SCIENCE PROGRESS 



Silica and the Silicates. By James A. Audley, B.Sc, F.I.C. Industrial 

 Chemistry series, edited by S. Rideal. [Pp. xii + 374, with 27 figures.] 

 (London : BailHere, Tindall & Cox, 192 1. Price 15s. net.) 



In his Preface to this volume the author tells us that " no previous English 

 author appears to have attempted to cover the same range of subjects within 

 the limits of a single volume." That he has attempted too much, particularly 

 as he is writing on technological subjects with which he has only a limited 

 acquaintance, and that he has evidently not had access to the scientific 

 literature while writing the book, has resulted in the production of a work 

 which is more likely to mislead than to instruct those into whose hands it 

 may fall. 



The scientific treatment of the subject can only be described as inaccurate, 

 and even as incoherent. Under the heading Silica one might have expected to 

 find a concise statement of our knowledge of the properties of that substance. 

 The Transformations of Silica are dealt with in sections scattered about the 

 book (pp. 33-6, 180, 260-3), and, though our knowledge of the subject is 

 not altogether satisfactory, the author is not justified in telUng us, within the 

 limits of a few lines, that, in silica bricks, quartz is transformed into tridymite 

 at 1,600°, that it is not altered by heating to high temperatures, and that, in 

 steel furnaces, quartz is altered into tridymite if the temperature exceeds 

 1,400°. Fenner's paper, published in the Journal of the Society of Glass 

 Technology in August 1919, sums up the actual situation quite clearly. Of 

 the specific heat of silica we are told practically nothing beyond the fact that 

 it " exhibits peculiarities." Nothing is said about the thermo-chemistry of the 

 silicates; and the section dealing with the Expansion of Silica (p. 13) is quite 

 unintelligible. The second section, headed Silicates, describes a number of 

 compounds with little regard to their technical importance. The account 

 of carborundum, ferro-silicon, and similar products should not have been 

 included in an already overcrowded work. 



The technical sections of the work are devoted mainly to a description of 

 processes, but they are so condensed that it is too often quite impossible 

 to grasp the author's meaning. In dealing with the firing of ceramic 

 products and bricks (pp. 200-4, 251-4) he describes down-draught, up-draught, 

 stack, and regenerative kilns ; but no one unacquainted with the industries 

 could gather the faintest idea of the construction and working of these kilns. 

 Grinding machines are figured and described, but there is no indication of the 

 purpose or service of the different types of plant. 



The author has ventured to write upon glass, of which he has neither a 

 practical knowledge nor even a knowledge of the literature of the subject. 

 He retails Grenet's obsolete ideas on the process of softening and annealing, 

 and ignores Twyman's scientific treatment of the subject, based upon Maxwell's 

 work on the relaxation of strain in viscous bodies. His treatment of Devitvi- 

 fication indicates that he has not read Bowen's paper on the subject, to which 

 he makes reference at the end of the paragraph dealing with it. His state- 

 ments with regard to glass and glass-making are often wildly inaccurate, 

 and it is quite evident that he knows nothing about glass furnaces, either 

 regenerative or recuperative. 



The editor tells us in his Preface to this volume that works of this kind will 

 provide " mental munitions for the coming industrial war." If it represents 

 the mentality of our leaders, that war is now lost. 



Morris W. Travers. 



Anthracene and Anthraquinone. By E. de Barry Barnett, B.Sc, F.I.C. 

 [Pp. xii-l- 436.] (London: Bailliere, Tindall & Cox, 192 1. Price27s.net.) 



The appearance of this book is particularly welcome, and the author is to be 

 congratulated on his success in a difficult and laborious task. During the last 



