REVIEWS . 159 



Prof. Findlay's monograph will, doubtless, find many new readers besides 



serving to refresh the memories of those who are already familiar with the first 



edition. 



F. A. M. 



Monographs on Industrial Chemistry. Edited by Sir Edward Thorpe, 

 C.B., LL.D., F.R.S. (London: Longmans, Green & Co., 1919.) 



(1) The Natural Organic Colouring Matters. By A. G. Perkin, F.R.S. , 



F.R.S. E., F.I.C., and A. E. Everest, D.Sc, Ph.D., F.I.C. [Pp. xxii + 

 655.] (Price 28^. net.) 



The shortage of synthetic dyes occasioned by the war has caused a renewed 

 interest to be taken in the natural dye-woods and colouring matters, so that from 

 the practical point of view no less than from the theoretical the present volume is 

 very welcome. It is somewhat remarkable that although a large amount of 

 research has been carried out on this subject during the last half-century, 

 particularly in this country, there has hitherto been only one book dealing with 

 it, and that not in English, namely Rupe's Chemie der Natiirllchen Farbstoff'e, 

 which is already somewhat out of date, so that the work under review should 

 supply a definite need among English chemical literature. 



The chapters deal with dyes belonging to the following groups : Anthraquinone, 

 Naphthaquinone, Benzophenone, Xanthone, Chalkone, Flavone, Flavonal, y-Pyrane 

 (including the Anthocyan group), Dihydropyrane, Coumarine, Dicinnamoyl- 

 methane, Diphenyldimethylolide, Tannins, Coumarane, Indole, and Isoquinoline, 

 and also with the colouring matters derived from Lichens and those of unknown 

 constitution. An appendix is given containing a list of the natural dyes. The 

 work is well indexed, and a full supply of references is provided, so that those 

 chemists whose interests lie in this direction will appreciate so complete and 

 authoritative an account of the subject from the pen of Prof. A. G. Perkin, to 

 whom we owe so much of our present knowledge of the natural colouring matters, 

 whilst those who have hitherto given little attention to this important and fascinat- 

 ing department of organic chemistry will probably be surprised at the large 

 amount of research that has been done which is so well summarised here, and it 

 should serve as an incentive to further work in this field. 



As stated in the preface, the intention has been to make the book not only of 

 interest to the student but of value also as a work of reference, and to this end 

 special attention has been directed, in the case of many of the substances, to the 

 details which are essential for their isolation and purification. This is especially 

 the case with the chapter on the Anthocyans, which affords a valuable account of 

 the latest work on this group. 



One could wish, however, that in a volume dealing with Industrial Chemistry 

 room could have been found for a few more details as to the practical methods for 

 handling and treating the crude dye-woods, etc., on a commercial scale. 



The book is well printed and reasonably free from typographical errors, and 

 one's only regret is that the exigencies of the moment have not permitted the use 

 of a more satisfactory quality of paper for so excellent a work. 



(2) Catalysis in Industrial Chemistry. By G. G. Henderson, M.A., D.Sc, 



LL.D., F.R.S. [Pp. x + 202.] (Price gs. net.) 



The subject-matter of this volume is divided up into seven chapters, dealing 

 respectively with the General Theory, General Inorganic Reactions and Prepara- 



