54 Proceedings of Royal Society of Edinburgh. [sess. 
was the Revue semestrielle des publications mathematiques , com- 
piled under the auspices of the Mathematical Society of 
Amsterdam. Its objects are almost exactly those of the Jahrbuch, 
but its plan is quite different. In the first place, its titles, accom- 
panied by short abstracts, are arranged according to countries , and 
within a country according to serials ; in the second place, since 
each title has prefixed to it the appropriate symbols indicating 
its subject according to the classification of the “ Congres inter- 
national de bibliographic des sciences mathematiques,” it can 
and does provide a subject-index in comparatively small space ; 
and in the third place, the abstract of a paper is, as a rule, given 
in the same tongue as the paper itself. Two parts appear in a 
year, each dealing with the literature of the half year ended 
three months previously — thus showing a marked promptitude 
as compared with the Jahrbuch , where the corresponding interval 
is not three months, but three years. In the first volume, embrac- 
ing the work of half a year, the book proper occupied pp. 1-96, 
the list of journals pp. 97-100, the subject-index pp. 100-109, 
and the index of authors’ names pp. 110-114. The cost of the 
book, it well deserves to be mentioned, is trifling, the subscription 
price for the yearly couple of volumes being only 8J francs. 
In the end of 1902 still another competitor appeared, namely, 
volume A of the International Catalogue of Scientific Literature , 
promoted by the Royal Society of London, and designed to be the 
cosmopolitan continuation in annual instalments of the nineteenth- 
century Catalogue of Scientific Papers above referred to. Its 
general object is the same as that of the Jahrbuch and Revue , 
save that abstracts are not given. A complete volume appears 
once a year, and contains (1) a list of the previous year’s writings 
arranged alphabetically according to authors’ names, and hence 
called “Authors’ Catalogue,” each title having appended to it a 
number indicating its subject and a number indicating its position 
on the list; (2) a “ Subject Catalogue,” in which the titles, printed 
anew, are arranged according to the order of their subject-numbers, 
and under any subject-number according to the alphabetical order 
of the authors’ names. The scheme of classification of subjects is 
neither that of the Jahrbuch nor that of the Revue. In the first 
volume the “Authors’ Catalogue” occupies pp. 47-111, and the 
