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Each hew subject is introduced by a string of 

 names of distinguished chemists who have been 

 concerned in its study (sometimes as many as 

 eight are given), but there is no indication of the 

 nature of their contributions, and again no refer- 

 efnces are given. Incidentally, it may be pointed 

 out that the names of French chemists are much 

 : in evidence. Under "Valency," Frankland's name 

 is not even mentioned. These are minor points. 



The arrangement, though somewhat novel to 

 EpgUsh chemists, is finding favour both in France 

 . and in America. There is no division into ali- 

 phatic and aromatic compounds, but the two are 

 combined. Thus chap. ii. includes all the hydro- 

 carbons, saturated and unsaturated, aromatic and 

 hydro-aromatic, and the same system is followed 

 throughout. The nitrogen compounds have a 

 chapter to themselves, and there are others on 

 organo-metallic compounds, heterocyclic com- 

 pounds, and colouring matters. 

 , ; (2) Prof, de Forcrand's class-book of chemistry, 

 which has reached a second edition, is written 

 for students who are entering on a course for the 

 P.C.N. and S. P. C.N. —that is to say, a certificate 

 .sanctioned by the Ministry of Public Instruction 

 for advanced study in physics, chemistry, and the 

 ijatural sciences, the P.C.N, representing a 

 standard intermediate between the baccalaurdat 

 and the licencid in science, and the S. P.C.N, 

 being the equivalent of the latter. 



The course is divided into two parts, inorganic 

 and organic, which are treated in separate 

 volumes. The inorganic section' is divided into 

 gdneraliUs , metalloids, and metals. The book is 

 not intended for, nor is it to be recommended to, 

 beginners. The general principles laid down in 

 the first section, which include such notions 

 as reversible and isomeric changes, the phase law, 

 mass action, displacement of equilibria, etc., 

 would be almost meaningless unless the student 

 were already acquainted with the phenomena upon 

 which these generalisations are built. Moreover, 

 the subjects are presented in a didactic manner, 

 in which general statements are laid down without 

 any attempt at adducing evidence for them. 



It seems to the writer that the old method, 

 which was so common formerly among authors of 

 science text-books, of introducing general prin- 

 ciples and definitions before any experimental facts 

 had been discussed, though perhaps philosophically 

 sound, is not the best way of applying the experi- 

 mental method-^that is, the method of reasoning 

 from facts to generalisations — and not only so, 

 but it is almost bound to lead, as in the present 

 case, to .didactic treatment. 



The same criticism applies to the volume on 

 organic chemistry. The linking of carbon atoms 

 NO. 2629, VOL. 105] 



by single and multiple bonds is assumed without 

 evidence, and so also is the structure of the 

 various organic groups. 



Generally speaking, the book is somewhat old- 

 fashioned in its arrangement, in spite of para- 

 graphs on modern topics. It suffers, too, from a 

 dearth of illustrations. Even if the student has 

 studied his subject experimentally, and is 

 acquainted with apparatus and methods, he is still 

 ignorant of many practical operations of a tech- 

 nical character or special apparatus used in the 

 preparation of rarer compounds which some good 

 drawings would help him to grasp. 



Having pointed out what seem to the writer the 

 chief defects of treatment, it should be added that 

 the information is well arranged, and covers the 

 most important facts without unnecessarily multi- 

 plying the number of compounds. It is curious 

 to find the subject of analytical chemistry, both 

 inorganic and organic, relegated to the end of the 

 volume on organic chemistry. 



J. B. C. 



Indian Beetles. 



The Fauna of British India, including Ceylon and 

 Burma. Coleoptera. Chrysomelidae (His- 

 pinae and Cassidinac). By Prof. S. Maulik. 

 Pp. xi-f-439. (London: Taylor and Francis, 

 July, 1919.) Price i guinea. 



THERE is evidence enough in this volume to 

 show that many months of assiduous work 

 must have gone to its preparation ; but it leaves 

 more than an impression that the author lacked 

 experience to begin with, and had not quite 

 mastered his subject. His descriptions are gener- 

 ally too long. An author of experience, using 

 better judgment, would have confined his attention 

 to essentials when describing species, and left out 

 the rest, thus saving himself and his readers both 

 time and trouble. It would have meant a lot in 

 a volume like this, where 388 species altogether 

 come under notice, and all but a few are described 

 at length. Where the descriptions are long and 

 the differential characters not clearly marked out, 

 the keys to genera and species need to be well 

 constructed and trustworthy. 



Prof. Maulik's keys do not always answer to 

 this description. His keys to species not infre- 

 quently contain diagnoses which, though fairly 

 long, are not quite long enough to enable the 

 text descriptions to be dispensed with altogether ; 

 and the key to his first group of genera is of 

 so little service that the reader is left to decide 

 which is the more to be trusted, the author or 

 his artist, the key or the text. He has nowhere 



