3^4 



NATURE 



[July ii, 191 8 



has c»mpelled the publishers to omit, for the 

 present, the list of periodicals cited. In the section 

 "Science and Technology, including Hygiene and 

 Sport," published in April as part of the 

 Athenaeum subject index for 1916, we are told 

 that 311 periodicals are cited. The editors state 

 that more than 500 periodicals have been indexed 

 in their class lists for 1915-16. 



The section " Science and Technology " of the 

 ''Athenaeum Subject Index to Periodicals " should 

 have a wide circulation at the present time, when 

 a knowledge of the best and most economical 

 methods of carrying out a great variety of tech- 

 nical processes is of such importance to the 

 country. The Council of the Library Association 

 is to be congratulated on having brought this 

 index into existence, and it is to be hoped that 

 it will receive such support as will enable the 

 work to be continued. 



OUR BOOKSHELF. 

 Essentials of Practical Geography. By B. C. 

 WaUis. Pp. XV + 2 13. (London: Macmillan 

 and Co., Ltd., 1918.) Price 45. 6d. net. 

 This volume, which contains a great deal of 

 original research work, is a valuable contribution 

 to the practical side of the science of geography. 

 It furnishes the teacher of the subject with a 

 representative collection of practical exercises on 

 the essential principles usually included in a four 

 years' course of geography in an average 

 secondary school. The 104 pages of part i. con- 

 tain what may be regarded as a minimum course 

 of practical geography. Part ii. (50 pages) is 

 devoted to supplementary exercises which may be 

 worked in the geography lessons or in the periods 

 assigned to arithmetic, mathematics, physics, 

 handwork, and drawing. The remainder of the 

 book deals with outdoor work and advanced map- 

 reading, revision exercises, etc. The work is 

 skilfully planned, there being varied exercises for 

 the beginner as well as for the advanced student. 

 The principle of contour lines leads to isotherms, 

 isobars, isohyets, etc. The diagrams showing 

 isopleths for Java and Kew are particularly in- 

 structive. 



The treatment of raininess is very full, several 

 of the author's sets of monthly raininess ma^s 

 being reproduced from the Scottish Geographical 

 Magazine and from the Monthly Weather Review 

 of the United States Weather Bureau. The ex- 

 ample on p. 142 shows clearly the method of ob- 

 taining the "raininess numbers"; but since the 

 actual monthly rainfall of Algiers for each month 

 is given correct only to the nearest inch, it seems 

 scarcely logical to calculate the theoretically 

 evenly distributed rainfall in inches to two decimal 

 places and to infer from the numbers so obtained 

 that February is the rainiest of four months, each 

 of which is credited with 4 in. of rain. If the 

 figures for the monthly rainfall of Bombay had 

 been given to a closer degree of accuracy, the 

 corresponding raininess numbers given on p. 143 

 NO. 2541, VOL. lOl] 



could have been made to agree with those assigned 

 to Bombay on p. 43. On p. 143 (sixth line from 

 the bottom) the word "quarter" should be 

 "third." 



At the end of the book is a useful glossary, a 

 collection of examples of subjects for debates, and 

 a set of indexes. W. M. C. 



Practical Organic and Bio-chemistry. By R. H. A. 



Plimmer. New and revised edition. Pp. x + 



636. (London: Longmans, Green, and Co., 



1918.) Price 185. net. 

 The speedy appearance of a new edition of this 

 work indicates that it has established itself as 

 a trustworthy and useful aid to practical bio- 

 chemistry. The chief characteristics of the pre- 

 vious edition, to which attention was directed in 

 Nature of January 13, 1916 (vol. xcvi., p. 532), 

 i-emain quite unaltered, and only slight changes 

 in detail have been introduced. These are com- 

 paratively few in number, and take the form of 

 modifications of methods of analysis and prepara- 

 tion rendered necessary by new publications. Thus 

 the new methods of preparation of the bile acids, 

 due to Schryver and to Mair, and the latest method 

 of estimating glucose in blood (MacLean), are 

 fully given. A new plate of absorption spectra 

 forms the frontispiece, and includes the spectra of. 

 chlorophyll and other leaf pigments, as well as 

 those of the colouring matters of the blood and 

 urine. Appropriately for the times the remarks 

 on diet have been recast, but the few lines devoted 

 to "vitamines" scarcely do justice to the present 

 state of our information with regard to those im- 

 portant dietary constituents. 



A welcome addition to the new edition would 

 have been some account of the methods employed 

 in the estimation of the products of bacterial fer- 

 mentation, a branch of bio-chemistry which has 

 recently become of considerable importance, both 

 from the scientific and the technical point of view. 

 In particular a description of the processes pro- 

 posed for the determination of mixtures of the 

 lower fatty acids would have been of great value 

 to many workers, although the problem has not 

 yet been satisfactorily solved. A. Harden. 



Yorkshire Type Ammonites. Edited by S. S. 

 Buckman. The original descriptions reprinted^ 

 and illustrated by figures of the types repro- 

 duced from photographs mainly by J. W. 

 Tutcher. Parts ix. to xv. (London : W. Wesley 

 and Son, 191 3-18.) Price 35. 6d. net each. 

 All students of ammonites will welcome this 

 latest addition to Mr. Buckman's work. It con- 

 tains nearly fifty excellently reproduced figures of 

 as many different species, accompanied by the 

 original as well as detailed modern descriptions. 

 The whole provides as good a substitute for the 

 actual specimens as can be desired. 



Seventee^n new genera are instituted, the fate 

 of which may be left to the future. It is unfortu- 

 nate that no guiding principle has been followed 

 consistently in devising new names. In accordance 

 with common practice the majority end in "iceras '* 



