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 

 index, the key to technical knowledge, and which is in 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. S., Jr. 



