5o6 



NA TURE 



[ArKii. 



1902 



as simple a result as possible, even' if approximate, but 

 really because his is not the correct solution of a pro- 

 blem, that obtained by Saint \'enant's method involving 

 series of transcendental functions. We miss the well- 

 known equilateral triangle and the algebraic solutions 

 representing sections approximately square. Chapter x. 

 deals with the collapse {flambement) of beams under 

 end thrust or torsion. 



" The elements of the mathematical theory of elas- 

 ticity" is the title of the last chapter. In it the 

 differential equations of elasticity are expressed in terms 

 of the displacements, and the applications include wave- 

 propagation, Saint Venant's torsion problem (still with- 

 out reference to the rectangle or equilateral triangle), 

 Boussinesq's and Hertz's theorems. 



A special feature of the book is the collection of 

 examples at the end of each chapter. These, of which 

 the solutions are given, are, as examples should be, 

 mostly straightforward applications, frequently numerical, 

 of the bookwork, and though some of them are neces- 

 sarily rather long, none of them are without some prac- 

 tical interest. It is very likely that many a mathe- 

 matician brought up on tripos riders might find the 

 numerical calculations puzzling at first, but is it not 

 essential to understanding a theory properly that it should 

 be tested by numerical examples and not merely by 

 "neat analytical results"? Another feature is the 

 synopsis of formula; at the end of the book. 



This is not exactly the book which a mathematician 

 would use to learn elasticity from by preference, but 

 then it was not written for mathematicians. In endeavour- 

 ing to present the theory of elasticity in the most prac- 

 tical aspect possible so as to bring it within the range of 

 engineering students, the author appears to have achieved 

 his object with remarkable success, or in the conventional 

 words of the reviewer, " this book is admirably adapted 

 to the requirements of the class of readers for whom it is 

 specially written." 



DETERMINATIVE BACTERIOLOGY. 



A Manual of Determinative Bacteriology. By Frederick 

 D. Chester. Pp. vi -t- 401. (New York : The Mac- 

 millan Company, 1901 ; London : Macmillan and Co., 

 Ltd.) Price \os. bd. net. 



ALL branches of science in the early stages of their 

 development suffer from the want of a uniform 

 nomenclature. But it is in the biological sciences, 

 especially zoology and botany, that the greatest confusion 

 has prevailed, more particularly in the naming of the 

 multitudinous forms of animal and plant life. Thanks, 

 however, to the codes of rules drawn up at various con- 

 ferences, and more or less universally accepted, the 

 systematic nomenclature of zoology and botany has be- 

 come much more uniform and simple, while these 

 branches both possess a recognised terminology for 

 descriptive purposes. 



It is otherwise with bacteriology. This science, though 

 primarily a branch of botany, has been mainly developed 

 by those who could not claim to be trained botanists, and 

 the bacteria have been studied and classified with little 

 reference to the relations existing among themselves and 

 to allied forms ; hence the nomenclature, both systematic 

 and descriptive, is in a chaotic state. Moreover, descrip- 

 NO. 1692, VOL. 65] 



tions of new forms are continually appearing in a number 

 of journals, so that it is extremely difficult without an 

 enormous expenditure of time to discover whether a form 

 has previously been described or no, as hitherto there has 

 been no catalogue of species available. It is with a view 

 to purge bacteriology of some of these reproaches that the 

 present work has been compiled. The author modestly 

 states in the preface that he "does not claim that the 

 system of arrangement is perfect. . . . The present tables 

 serve, therefore, only for purposes of identification and 

 not necessarily for those of classification." The opening 

 chapter is devoted to an account of the morphology and 

 biology of the bacteria ; in the second a genuine attempt 

 is made to devise a system of terminology for descriptive 

 purposes. The various forms of growths, of colonies, &c., 

 receive appropriate names, so that what was formerly a 

 long description may be condensed into a few words. 

 For instance, the gelatin stab culture of anthrax is " an 

 arborescent growth becoming a crateriform to saccate 

 liquefaction," and the agar colonies of the same organism 

 are simply " floccose." The preparation of standard 

 nutrient media is then described, a reaction of -(- o'5 

 being preferred to that of 4- I'S adopted by the Committee 

 of the American Public Health Association. Some stain- 

 ing methods are next briefly mentioned, and a few pages 

 are devoted to a study of the chemical functions of bac- 

 teria, a table of chemical separations, and a scheme for 

 the study of bacteria. 



In chapter iii. the classification of the bacteria is 

 dealt with, that adopted being on the basis of the one 

 described by Migula in his " System der Bakterien,"and 

 the various species are tabulated at length and upon a 

 definite scheme. This portion of the book occupies more 

 than 300 pages and must have entailed considerable labour 

 in its compilation. The cultural and other characters of 

 each organism are described upon a consistent plan, 

 while the various species are divided up into small groups 

 by certain prominent characteristics, such as chromogenic, 

 liquefying, Gram-staining and other properties. By this 

 subdivision, and the synopsis of characters given before 

 each group, it is possible, as the author points out, to 

 place a culture in the hands of a student and for him to 

 determine the species. Those who are acquainted with 

 the older works of Eisenberg, Lustig, &c., will accord a 

 hearty welcome to these tables. The classification, as 

 stated before, is that of Migula, but the nomenclature of 

 species has been made to accord with the rules of 

 botanical nomenclature, with a rigid insistence upor> 

 binomial names and upon the rule of priority. At the 

 same time, the synonymy of, and earliest reference to, 

 each species is given. This is no doubt a great advance, 

 though perhaps inconvenient at first, as it involves the re- 

 naming of a number of familiar species, sometimes with 

 far less appropriate names than they have at present. 

 For example, the bacillus of mouse septicemia was con- 

 veniently termed the Bacillus murisepticus by Fliigge ir> 

 1886, but a year previously Trevisan had named it the 

 Bacterium insidiosum, and therefore " insidiosus" by 

 the rule of priority, must stand as the specific name. 

 Curiously enough, having discussed this very organism as 

 an example of the rule of priority at length at p. 48, 

 when it comes to the actual description of it (p. 353) the 

 author tabulates it as Mycobacterium murisepticum in- 



