REVIEWS. 
231 
and convey even to noil-surgical readers a considerable amount of instruc- 
tion. Mr. Canton’s treatise, while being accurately scientific, is devoid of 
that professional pedantry which we so frequently find in surgical books ; 
and it combines so much historic lore with ophthalmic fact, that one travels 
over its pages with almost as pleasurable a feeling as though it had been a 
romance. 
MANUAL OF THE METALLOIDS.* 
S CIENCE is not behind-hand on the other side of the Irish Channel. 
Messrs. Galbraith and Haughton, both Fellows of the University of 
Dublin, have been among the foremost in giving an impetus to Irish 
science, and we on this side of the water have materially benefited by 
their exertions. These gentlemen have lately been engaged in bringing- 
out a new series of Manuals, uniform with those on pure and mixed 
mathematics ; but this time the natural and experimental sciences have 
received their attention. The book upon our table is the third of the series, 
and by far the best of the three ; for whilst the two others are beset with 
technicalities of a very unnecessary character, the present one is at once 
philosophic and clear. This, however, is only what we might have ex- 
pected from so distinguished and erudite a physicist as the Professor of 
Chemistry in the University of Dublin. The introduction, which to our 
mind is the most successful portion of the work, extends over about one 
hundred pages. It is divided into a number of sections, of which one is 
devoted to each of the following subjects : — Laws of Combination, Equi- 
valent Numbers, Atomic Weights, Notation, Law of Volumes, Atomic 
Volume, Isomerism, Isomorphism, Dimorphism, Reaction of Bodies on each 
other, Berthollet’s Views on Decomposition, and the Unitary System. The 
latter is detailed more clearly than we have found it to be in any other 
treatise, and we can commend it as a most impartial exposition of both 
sides of the case. The more purely chemical division of the Manual is 
thoroughly good, but has little novelty, save the introduction of a far 
larger proportion of experimental physics than is usual, — a feature, by the 
way, which we consider is much in its favour. The subject of coal gas is 
dilated on at length ; and there is a useful appendix “ On the Analysis of 
Gases.” In conclusion, we may observe, that Dr. Apjohn’s Manual bids 
fair to become a frequent visitant to both laboratory and lecture-room. 
A MANUAL OF MINERALOGY.f 
I N this book the mineralogist meets with an old friend in a somewhat 
new garb. The present volume, which is one of a new edition, has 
been revised and enlarged, and contains much matter unpossessed by the 
* “ Manual of the Metalloids.” By James Apjohn, M.D., F.R.S., 
M.R.I.A., &c.. Professor of Chemistry in the University of Dublin. 
London : Longman & Co. 1864. 
t “ Manual of Mineralogy,” &c. By James D. Dana, A.M. London : 
Triibner & Co. 1863. 
