ee ee ee ee eee ete eT 
Review of Cleaveland’s Mineralogy. 47 
and standard of comparison, in describing the other species 
which have lime. for their basis, and some of which are com- 
paratively tare. The same remark we would make upon 
quartz, and its concotnitant, pure siliceous stones. There ap- 
pears to us a high advantage in making these minerals clearly 
known first, before we proceed to those which are much more 
rare, and especially which are much harder, and possess the 
characters of gems. For example, if a learner has become 
acquainted with quartz, chalcedony, flint, opal, chrysoprase, and 
jasper, he will much more easily comprehend the superior 
hardness, &c. and different composition of topaz, sapphire, 
spinelle ruby, chrysoberyl, and zircon, which we should much 
prefer to see occupying a later, than the first place in a tabular 
arrangement; and, although topaz, by containing fluoric acid, 
appears to be in some measure assimilated to saline mine- 
rals, it is in its characters so very diverse from the earthy 
salts, that we have fair reason to conclude that the fluoric 
acid does not stamp the character; and, as it bears so close 
aresemblance to the ruby and sapphire, which evidently de- 
rive their principal characters from the argillaceous earth, 
we perhaps ought to infer that this (the topaz) does so too.— 
Indeed Professor Cleaveland has sufficiently implied his own 
opinion, by giving these minerals a juxtaposition in his table, 
although the same reasons which induced the placing of the 
topaz next to the earthy salts, could not have justified the 
placing of the sapphire there. On these points we are not, 
however, strenuous ; they are of more importance if the work 
be used as a text-book for lectures, than as a private compan- 
ion. With respect to the completeness of Professor Cleave- 
land’s tabular view, we have carefully compared it with the 
third edition of Jameson’s Mineralogy; and although a few 
new species, or sub-species, and varieties, have been added, 
they are’ in general of so little importance, that Professor 
Cleaveland’s work cannot be considered as materially defi- 
cient; and the few cases in which it is so, are much more than 
made up by his entirely new and interesting views of American 
mineralogy, to which no parallel is to be found in any other 
