of
the leading principles of Mineralogy was indispensable, as ar
introduction to his main design ; and that Ciystallography, the mother
of Gems, should be explained, before treating them when prepared for
the dealer or wearer : he concluded, therefore, to commence his
treatise by following the Terminology of Nichols' Elements of
Mineralogy, of which he copied the greater part, along with some
remarks of Dufresnoy, from the study of whose great work on Mineralogy
he derived much valuable information. He feels it incumbent on him
publicly to acknowledge his obligations to the author of the Elements
of Mineralogy, for the concise and lucid descriptions contained in the
first part of that work, which should be read by every student of
Mineralogy. In the second part of this work, which treats of Gems, the
author has followed his own system in their classification ; that is,
he has arranged them according to their intrinsic value, and not
alphabetically, as has been done by some authors, nor as oxydized
stones—a system adopted by others. The diamond is placed at the head of
the whole class of Gems, and the others follow in the order of their
commercial value. Some minerals which are not properly Gems have been
included in the list, either on account of certain specific characters
which they possess, or their applicability to some useful purpose. Many
mineral substances which belong properly to the geological or
economical department of the science of mineralogy, have been treated
in this part of the work; but they occupy so important a position in
the economy of life, that their introduction cannot be regarded as an
intrusion. Reference is here made to the detailed account of coal,
marble, granite, and sienite—are they not as valuable as the Gems
described in this treatise ? are they not the foundation on which is to
be reared the opulence of future generations? have they not already
contributed to the aggrandizement of the United States, the most
enterprising nation on the globe ?
The revenue arising from the annual production of eight
