? 
Review of Dana’s Mineralogy. 387 
purpose. We have found it impossible to procure the type of 
Berzelius even in London, ready made. Probably it is owing to 
this difficulty that these useful symbols have been so slowly in- 
troduced out of continental Europe. The double type gives in- 
stant notice of the double base, and we shall hereafter employ 
them in this Journal. 
We may add that the mineralogical cabinet of Yale College 
has been recently arranged, nearly, on this plan, The tabular 
arrangement of these formulas secures many advantages not at- 
tained when they are distributed through the volume each under 
its species. 
Rocks and mineral aggregates.—Part VIII. of this volume is 
devoted to a description of the various mineral aggregates which 
form the rock masses of our planet. It is not usual to include 
these in a mineralogical treatise, nor are they treated here in any 
other than a mineralogical way. There is an expectation on the 
part of most general readers of finding, when they take up a min- 
eralogical book, an account of the principal rocks, and when they 
search the index in vain for such words as porphyry, granite, ba- 
salt, and the like, they very naturally feel a degree of disappoint- 
ment. This chapter is intended to meet that expectation. Its 
arrangement presents at every step the same admirable power of 
generalization and order which so eminently distinguish all the 
author’s works. 
The work is brought to a close by a mineralogical bibliogra- 
phy posted up to the present time: in it are registered all the im- 
portant publications on the subject, from Theophrastus down, 
and in the American portion, every paper on the subject, which 
has been published, even in a transient magazine, is recorded. 
The student in his researches will duly appreciate the value of 
this unpretending catalogue. Nor must we fail to mention the 
inder, the key to technical knowledge, and which 1s 10 the pres- 
ent case most satisfactorily full and comprehensive ; every known 
name and synonym ever used in the science is introduced. 
But we must abruptly close this notice, already too long, with 
the remark, that it ‘gives us pleasure to believe that it requires 
but few works like the present, to give American science a 
name, which will merit, if it does not receive, the respect of 
the scientific world. B. 8., Jr. 
