January 31, 189 



.] 



NATURE 



1^1 



lakes. The description of the existing " earih-forms," or 

 geographic types, occupies the first 460 pages of the 

 second volume. These "earth-forms" are divided into 

 eight types — plains, heaped-up mounds, such as moraines 

 and dunes, valleys and the highlands through which they 

 run, basins, mountains, areas of subsidence, and finally 

 fissures and caves. The characters, classification, 

 method of formation and terminology, including both 

 local and scientific names, are stated in detail. A sketch 

 of the literature of each type is also given. The chapters 

 on " Wannen " or basins, and on mountains, are probably 

 the best. The book closes with an account of the ocean;, 

 and the deposits on their floors. 



The one serious drawback to this book is its complete 

 neglect of the evidence of zoological distribution. Thus, 

 for example, the questions of the origin of the Caspi in 

 Sea and the lakes of Nicaragua, are fully considered, but 

 no reference is made to their faunas. No theory, how- 

 ever, could be accepted which failed to account for the 

 anomalous characters of these. But it would be too much 

 [" etpect Prof. Penck to show the same mastery of the 



'.erature of biology as he does of geography and geology. 

 In this respect, Walther's book is superior to that of 

 I'cnck. But it is idle to estimate their respective merits, 

 lor the three works are so different. One cannot com- 

 pare Walther's statements of the principles of correlation 

 with Rothpletz's detailed mapping, and either with 

 I'enck's digest of literature. I'enck's, however, will pro- 



lably prove the most generally useful of the three. An 

 llnglish translation would be of great service, by calling 

 attention to a branch of geography that has been un- 

 accountably neglected in this country. Thus, in the 

 I ieographical Society's " Hints to Travellers," instea ! of 

 the details of Richthofen's " Fiihrer," the subject is not 

 even mentioned. A translation would, moreover, neces- 

 sitate greater precision in the definition of geographical 

 terms, and the introduction of many new ones, for which 

 there are now no equivalents in English, and which are 

 essential to the scientific treatment of geography. 



J. W. Gre(;orv. 



ORGAMC CHEMISTRY. 



The Rise and Devclopineiil of Ori^anic Cliciuisliy. By 

 Carl Schorlemmer, LL.D., F.R.S. Revised edition, 

 edited by Arthur Smithells, B.Sc, Professor of 

 Chemistry in the Yorkshire College, Leeds. (London : 

 Macmillan and Co., 1894 ) 



FOR some time this excellent historical survey of the 

 development of organic chemistry has been out of 

 print, and students of chemistry will heartily welcome 

 the appearance of a second edition, which has been 

 extended, in order to include a review of the more im- 

 portant results of the original investigation of the last 

 ten to fifteen years. 



Facing the title-page is an exceedingly good likeness of 

 Schorlemmer, admirably reproduced from a photograph ; 

 then follows a short biographical notice, giving a brief 

 sketch of the author's career, in which his brilliant 

 researches are described. This is a very welcome 

 addition to the book, because, as the editor points nut, 

 Schorlemmer, with characteristic modesty, mentions 

 NO. 1318, VOL. 51] 



these r^earches only on two occasions in the book 

 (pp. 141 and 197), and then but very briefly. 



Chapters i. to v. are very much the same as in the 

 first edition, only a few slight alterations having been 

 made. Chapter vi. deals with the perfection of the 

 I methods of organic analysis by Liebig, and these impor- 

 tant researches, which affected in such a marked manner 

 the subsequent development of organic chemistry, are 

 perhaps scarcely di^cu-sed at sufficient length ; a more 

 detailed account of the history of organic analysis is to 

 be found in Roscoe and Schorlemmer's " Treatise of 

 Chemistry" (vol. iii. p. 40). This chapter vi. also con- 

 tains a short sketch of the work which led to the dis- 

 covery by Raoult of his well-known method of deter- 

 mining the molecular weight knoivn as the cryoscopic 

 method. 



Chapters vii. and viii. have not been much altered, but 



chapter i.\-., which deals with the constitution of benzene, 



tautomerism, and the asym:netric carbon atom, has, as 



was to be expected, been largely added to, and made to 



I embrace most of the important results of recent work. 



The constitution of benzene is dealt with in a veiv 

 interesting manner. Baeyer's researches, on succino- 

 succinic ester, which led to the rejection of Ladenburg's 

 prism formula, are discussed, as well as those of Bam- 

 berger, on the reduction of naphthalene derivatives, the 

 results of which may be said to have completely con- 

 firmed Baeyer's views. 



After a short description of Laar's tautomeric hypo- 

 thesis, the remainder of the chapter is taken up with 

 Le Bel and van't Hoffs theory of the asymmetric 

 carbon atom, and with VVislicenus' development of this 

 theory. In a future edition, more emphasis might, per- 

 haps, with advantage be laid on the general applicability 

 of these theories, so that the student may not receive 

 the impression that they have only been found valuable 

 in the explanation of isolated cases, as, for example, the 

 isomerism of the malic and tartaric acids, and of fumaric 

 and maleic acids. 



The first part of chapter x. is devoted, principally, to 

 the history of organic synthesis, and contains an account 

 of Frankland and Duppa's work on aceto-acetic ester, 

 and of Conrad's researches on malonic ester, showing 

 the value of these ethereal salts in synthetical work. 

 The synthesis of malic, tartaric, and citric acid is also 

 mentioned. 



A very valuable historicaf sketch of the chemistry of 

 the sugars, including a clear exposition of the more 

 important results of E. Fischers classical researches, fol- 

 lowed by an account of Ladenburg's synthesis of coniine, 

 and of the synthesis of uric acid, by Horbaczewski, con- 

 cludes this excellent chapter. 



The remainder of the book does not differ materially 

 from the first edition, except that a very good index of 

 authors' names and subjects has been added. 



Students of organic chemistry must always be in- 

 terested in the development of the science, and to them 

 this work will be cordially welcome. It is a thoroughly 

 readable book, written throughout in an attractive 

 manner, and comprisuig in one small volume all the 

 facts necessary for understanding the growth of organic 

 chemistry. 



Schorlemmer wrote, whenever possible, in German, 



