808 



SCIENCE. 



[N. S. Vol. VII. No. 180. 



Bibliographia geologica ripertoire des travaux 

 concemant les sciences geologiques dresse d'apres 

 la classification dScimale et formant la partie 

 (549-571) de la Bibliographia Universalis. Par 

 Michel Motjelon, Directeur du Service g6o- 

 logique de Belgique avec la collaboration de 

 G. SiMOENS, Docteur en sciences min^rales, 

 attache au Service. Bruxelles, 1898. 

 This publication Is accompanied by two 

 pamphlets, ' Liste des periodiques compulses 

 pour 1' elaboration de la bibliographia geologica 

 dresse d'apres la classification decimale par le 

 Service geologique de Belgique,' and ' La classi- 

 fication decimale de Melvil Dewey appliquee aux 

 sciences geologiques pour I'elaboration de la 

 bibliographia geologica par le Service geologique 

 de Belgique.' 



Bibliographic work of the science of geology 

 has heretofore been of a very fragmentary 

 character and limited both geologically and 

 geographically. But now we have here an at- 

 tempt to compile for a definite period a universal 

 bibliography of geologic literature. Biblio- 

 graphic works have always been welcomed by 

 geologists, and this one will surely receive its 

 full quota of approval. The difficulties which 

 attend the labor of preparing bibliographies of 

 books written in languages with which one is 

 more or less unfamiliar can hardly be realized. 

 The various monographs, bulletins, proceedings, 

 transactions, journals, memoirs, etc., published 

 in many different cities and under the auspices 

 of various government organizations and socie- 

 ties are full of pitfalls to one in a distant coun- 

 try who is not personally familiar with their 

 methods of procedure, times of publication, etc. 

 The various omissions in this work which are 

 due to such causes have been passed over. At- 

 tention is here directed to the method of arrang- 

 ing the bibliographic matter and also to the 

 scheme of indexing, which is somewhat new in 

 its use for this purpose, and to which there ap- 

 pear to be certain fundamental objections which 

 are inherent in the plan itself. 



In this bibliography there is no alphabetic ar- 

 rangement by authors' names, not even under 

 the various subheadings. Apparently the 

 papers are arranged under subheadings accord- 

 ing to the index number — that is, papers that 

 belong under one subheading and have the 



index number 549.1 are grouped together ; then 

 549.2 follows, and so on. Hence if you wish to 

 find a particular paper you must know the sub- 

 division of geology and index number under 

 which it would be listed before you could find 

 the reference to the proper publication. The 

 arrangement is particularly unfortunate, and it 

 is quite evident that in any bibliographic publi- 

 cation there should be one alphabetic arrange- 

 ment by authors' names. 



The classification of any branch of science is 

 something that is always subject to modifica- 

 tion, as our knowledge increases and ideas 

 change. Such a classification should not only 

 be elastic, but able to be rearranged to suit the 

 ideas and needs of the individual without im- 

 pairing its usefulness as a whole. The subject 

 classification adopted for this portion of the 

 Bibliographia Universalis will hardly meet with 

 general approbation. The character and oc- 

 currence of metaliferous deposits can be classi- 

 fied under mineralogy only on the widest ac- 

 ceptation of the term, and is a rule not applicable 

 to a minute classification. Certain subdivisions 

 of stratigraphy under the heading geology are 

 local, and are recognized by but few geologists, 

 and only in restricted areas. 



The decimal system of classification employed 

 in this bibliography is used for putting books 

 in order on the shelves of libraries, and is a 

 quick method of finding them. Its value for 

 such a purpose is no criterion by which to judge 

 of its usefulness in a detailed classification of our 

 knowledge of various subjects. Such an arbi- 

 trary system might be useful to the individual 

 formulating it, but does not necessarily fulfill 

 the requirements of a number of individuals. 



The numerical system is open to the further 

 objection that but a small amount of indexing 

 is practicable, and that of a very general char- 

 acter. To illustrate this take the following 

 example from this publication. In the notice 

 of the Monograph on the Denver Basin of Col- 

 orado, by Emmons, Cross and Eldridge, the 

 index number given is 551.7. 55 refers to 

 geology, 551 to the physical structure of the 

 globe, and 551.7 to stratigraphy. Indexing un- 

 der such general headings conveys a very inade- 

 quate conception of the extent and character of 

 this publication. To index it with some degree 



