Stipplement to '■' Nature" November 14, 1901, 



SUPPLEMENT TO "NATURE." 



A MODERN TEXT-BOOK OF CHEMISTRY. 

 Roscoe-Schorletitvier's aiisfiiJsrUchcs Lehrbuch der Cliemie. 

 By Jul. Wilh. Briihl, Professor in the University of 

 Heidelberg. Vol. vii. Part v., and \'ol. viii. Part vi., 

 Organic Chemistry, in cooperation with Eduard Hjelt 

 and Ossian Aschan of the University of Helsingfors. 

 Pp. xxvii + 1320 and x.wix + 1045. (Brunswick : 

 Friedrich Vieweg und Sohn, 1899-igor.) 



THE well-known treatise on chemistry by Roscoe and 

 Schorlemmer, which has for so many years been 

 a standard work in this country, is now being published 

 in a totally revised form in Germany, and two parts of 

 the German edition have been received for review. The 

 preceding (sixth) volume, containing an account of the 

 heterocyclic five-membered rings, was published in the 

 spring of 1898, the seventh in July 1899, and the eighth 

 in .May of the present year. The ninth and concluding 

 volume, dealing with albuminoid compounds, ptomaines, 

 toxines and enzymes, is promised in a few months' time, 

 so that the work has been pushed on with remarkable 

 rapidity. Certain sections, moreover, such as the por- 

 tions dealing respectively with the vegetable alkaloids 

 and albuminoid compounds, have been published as 

 separate monographs, the former having already been 

 noticed in these columns by the present writer. 



Taking the two volumes before us in due order, the 

 seventh, which consists of 1320 closely printed pages, is 

 devoted to the six-membered heterocyclic ring com- 

 pounds. These comprise the pyrone, pyridine, quino- 

 Hne and isoquinoline groups and their hydro-derivatives, 

 the alkaloids related to this class, the azines, the uracil 

 and purine compounds, the pyrazines, piperazines, quin- 

 oxalines, azine colouring-matters, kyanidines, cyanuric 

 acid derivatives, &c. Dr. Briihl, in his prefatory notice, 

 calls attention to the fact that the whole of this enormous 

 mass of material has been worked up within the short 

 period of one year, the editorial work having been con- 

 cluded towards the beginning of 1899. The section on 

 the metallic compounds of pyridine, which occupies 

 twenty-two pages, has been contributed by Prof. .Alfred 

 Werner, of Zurich, while Prof. Emil Fischer has revised 

 the portion relating to the purine group. We are further 

 told in the preface that the aim of the authors has been, 

 not only to present a complete, but also a readable ac- 

 count of modern organic chemistry, and each chapter 

 accordingly commences with a concise but thorough 

 historical introduction, which will be found most interest- 

 ing by all who desire to follow the steps by which our 

 knowledge of the different groups has been built up. 



Comparing the present work with its English prede- 

 cessor, it will be seen that the rapid development of 

 organic chemistry has necessitated much more than mere 

 revision. Whole sections have been re-written, and but 

 little of the original " Roscoe and Schorlemmer" beyond 

 the general plan is left. That this work of compilation 

 and coordination has been carried out most thoroughly 

 and efficiently is sufficiently guaranteed by the names of 

 Dr. Briihl and his coadjutors. In view of the great 

 NO. 1672, VOL. 65] 



advance of the science of chemistry in every direction, it 

 is practically impossible to produce a text-book, however 

 complete, which can be expected to survive for more 

 than a limited period. Such a work as that under con- 

 sideration must be considered as presenting a complete 

 epitome of the science down to the date of its publication ; 

 and as a standard of reference for students and workers 

 it may be confidently asserted that it is destined to have 

 a long and useful career. How many years will elapse 

 before a new edition is called for — whether it will be 

 possible to keep pace with the progress of discovery by 

 the issue of supplementary volumes, whether it may not 

 be necessary to revise particular volumes from time to 

 time — these are questions of procedure to which time and 

 the exigencies of the German publishing trade can alone 

 give a reply. But if the reader whq, without being a 

 specialist in this department of chemistry, is interested 

 in a general way in the development of our knowledge of 

 the carbon compounds will make such a comparison as 

 is here suggested, he cannot fail to be struck by the 

 manifest indications of ceaseless activity on the part of 

 investigators in this practically inexhaustible domain. 

 Take, for example, the purine group, which has been 

 attacked with such brilliant success by Emil Fischer and 

 his pupils. It is about seventeen years ago since 

 Fischer's first communication on this subject, and 

 at the present time it may be said that our 

 knowledge of the constitution of all the physiologically 

 important members of the group is fairly complete, and 

 what makes this chapter of research so particularly 

 interesting is that not only have the majority of these 

 products of animal and vegetable life been synthesised, 

 but a large number of new purine derivatives which have 

 never been elaborated by "vital" processes have been 

 called into existence by virtue of that mastery over the 

 chemical molecule which invariably follows when the 

 constitution of the type has been established. From the 

 same point of view the pyrone group is likewise of 

 special interest. Colouring-matters, such as chrysin, from 

 the buds of various species of Populus ; apigenin, which 

 occurs as a glucoside in parsley ; fisetin, from Rhus 

 cotinus, R. rhodanihema and Quebracho Colorado ; lute- 

 olin, from Reseda luteola ; kampheride, from the Chinese 

 galanga root {Alpinia pfficitiarum) ; quercetin, which 

 occurs as a glucoside in quercitron bark [Ouerciis tinc- 

 toria) and in many other plants ; rhamnetin, from buck- 

 thorn berries, &c. ; isorhamnetin, from the wall-flower ; 

 morin, from fustic ; euxanthone, from Indian yellow ; gen- 

 tisin, from the root of Gentiana luteola, and other well- 

 known and definite products of vegetable origin are now 

 known to belong to the benzo-y-pyrone and dibenzo-y- 

 pyrone types. In establishing the constitution of these 

 compounds A. G. Perkin, of the Yorkshire College, has 

 taken an important part. Only two years ago the authors 

 of the present volume were obliged to state, in summing 

 up our knowledge of the benzo-y-pyrones, that "none of 

 these natural colouring-matters have as yet been syn- 

 thesised" (p. 49). Of the dibenzo-y-pyrone (xanthone) 

 group, euxanthone had been synthesised by Liebermann 

 in 1889 and gentisin by v. Kostanecki and Tambor in 

 1894. Since the appearance of the present volume the 

 synthetical production of chrysin, apigenin and other 

 natural colouring-matters of the same group has been 



