REVIEWS 667 



and again the section on anthraquinone dyes completely omits all reference 

 to the highly important group of the Algol colours. 



In the circumstances it might have been better to have delayed publication 

 for awhile until the manuscript had been revised and completed ; perhaps such 

 a revision may be possible before the issue of the next edition. 



Nevertheless, in spite of these drawbacks, the book contains much that 

 is of value to dye chemists, and will no doubt be of assistance to those who 

 have to deal with the manufacture of colouring matters. 



F. A. Mason. 



A Treatise on Chemistry, Vol. I. the Non-metallic Elements. By the Rt. 

 Hon. Sir H. E. Roscoe. F.R.S., and C. Schorlemmer, F.R.S. Fifth 

 Edition, revised by Dr. J. C. Cain. [Pp. xv + 968, with 226 illus- 

 trations and a portrait of John Dalton.] (London : MacmUlan & Co., 

 1920. Price 305. net.) 



Roscoe and Schorlemmer's treatise is such a classic that it is almost as 

 difficult to find anything fresh to say about it as it would be to offer a 

 personal criticism of an old friend. 



Since the appearance of the fourth edition of the work chemistry has 

 suffered a severe loss by the death of Sir Henry Roscoe, and it is a fortunate 

 matter that Dr. Cain was already associated with the author in the earUer 

 edition of the book, so that he has been able to preserve its general character 

 and style. 



The endeavour has been made to bring the book up to date by inserting 

 references to recent work, but one is rather left with the impression that it 

 is a case of trying to put new wine in old bottles. 



When, for instance, as on p. 427, we find work published in 1899 referred 

 to as " recent," one cannot help feeling that the book really requires a funda- 

 mental rearrangement and rewriting rather than a mere revision unless it 

 is to remain simply a readable history of twentieth century chemistry. 



Many of the illustrations, also, are a trifle too archaic to be convincing, 

 and would be all the better for a drastic revision. 



It is somewhat remarkable that the immense Louisiana sulphur deposits 

 are dismissed in a line ; also, having regard to the scientific and technical 

 importance of the synthetic production of ammonia and its oxidation to 

 nitric acid, justice has hardly been done to these subjects by the space 

 allotted to them. 



Again, it would be interesting to know how many sulphuric acid works 

 continue to employ platinum stills for concentrating their acids, as stated 

 on p. 428, with platinum at ^40 an ounce ! There does not appear to be 

 any mention of the use of fused quartz for the purpose, or of acid-resistant 

 iron. 



Probably what is wanted is a group of chemists working under Dr. Cain's 

 direction to assist him with the very laborious work entailed in revising such 

 a book, so that the less important details may be removed to give place 

 for more modem matter, otherwise there is considerable danger of the 

 educational value of the book being diminished by the retention of subjects 

 which are rapidly becoming merely of historical interest. 



The printing and general arrangement of the treatise continue, as might 

 be expected, to be a model for chemical publications, though the purpose of 

 the uncut pages is not very clear ; they are more favoured by the bibliophile 

 than by the chemist. 



The fact that the book has reached its fifth large edition is a proof that 

 there is always a demand for a really readable and reliable textbook of 

 inorganic chemistry, and chemists owe their thanks to Dr. Cain for having 

 supervised the issuing of the present edition. 



F. A. M. 



