PREFACE. IX 



Naturalists. A view of both of these, for the convenience 

 of those who possess collections, will be annexed to the 

 second part of the work alluded to above. 



* 



The trivial names are employed in the Characteristic as 

 has been already remarked, in all those cases where they 

 are possessed of them; in other instances, they are desig- 

 nated by their chemical or natural-historical epithets. To 

 avoid however, in two instances of recently discovered 

 American minerals, the long, chemical designations bestow- 

 ed upon them by Dr. THOMSON, the author has ventured 

 upon two new names : one case is that of the Bi-silicate of 

 Magnesia of Bolton, Mass., the other is that of the Ferru- 

 ginous silicate of Manganese of Stirling, New-Jersey ; the 

 the former, he has called Boltonite to commemorate a cel- 

 ebrated deposit of minerals, and the latter Troostite, in 

 honor of Dr. TROOST, a gentleman whose services and 

 accomplishments in Mineralogy are too well known to re- 

 quire any apology for this employment of his name. 



But while the present treatise was primarily intended to 

 answer the wants of private students, the author regards it 

 as no less applicable to the circumstances of those who enjoy 

 personal instruction. No oral communications can be a sub- 

 stitute, surely, for an acquaintance with Terminology. This 

 constitutes in fact the preliminary occupation of the Lec- 

 turer on the science; and it is here chiefly, that the Instruct- 

 or who possesses the requisite models and specimens ren- 

 ders an important service to the pupil. The way in which 

 this department is treated in the present work, being that 

 of a series of connected propositions, will favor the impor- 

 tant exercise of recitation and review, which is the only 

 method by which the Teacher can satisfy himself, whether 



