384 Notices of Books. [July, 
he has undertaken. His work needs no recommendation ; it will 
be, if it has not already been, placed on the shelves of every 
scientific library. It should be known that the scale of wave- 
lengths adopted is applicable to spectroscopes of all sizes; there 
is consequently no difficulty in its universal application. 
Index to Gmelin’s Handbook of Chemistry. By Henry Watts, 
B.A., F.R.S., F.C.S., Editor of the ‘“‘Journal of the Chemical 
Society.” London: Harrison. 1872. 
THE last volume of this important chemical work has now been 
offered to the public. To chemists, and to all interested in 
chemical manufactures, the value of Gmelin’s ‘“‘ Handbook” is 
incomparable ; and it is due to us to make known to those 
intending to complete the set of these volumes that the earlier 
volumes are becoming scarce, and that early application will be 
needed to possess those remaining. Subscribers who have paid 
their subscription for the year 1864 will have forwarded to them 
the Index and the concluding (eighteenth) volume. The Index 
is very copious, reference being made to volume and page. 
Every subject is included under as many heads as possible. It 
is entirely unnecessary to recommend the work. 
The Year-Book of Facts in Science and Art. By Joun Timps, 
Author of ‘‘ Curiosities of Science,” &c. London: Lockwood 
and Co. 1872. 
Tuis is a well-arranged digest of the most important discoveries 
and improvements of the past year. The title-page is faced with 
a clear engraving from a photograph of Sir W. Thomson, F.R.S. 
Elementary Natural Philosophy. Being a Course of Nine 
Lectures, specially adapted for the use of Schools and 
Junior Students. By J. Ciirron Warp, F.G.S., Associate 
of the Royal School of Mines; of Her Majesty’s Geological 
Survey. London: Triibner and Co. 1871. 215 pp., 8vo. 
Tuis little book is evidently intended to serve a double purpose, 
as a handbook for the very young student, and as an aid to the 
schoolmaster who may wish to introduce the study of elementary 
physics into his curriculum. It contains the latest experiments 
likely to answer the end in view. The work is altogether very 
praiseworthy. 
