PREFACE. XI 



ries of its properties. A class thus instructed, it is believ- 

 ed will soon become skilful in the practice of the art, 

 and be able to form a proper conception of the contents of 

 the mineral kingdom. As to what relates to the geographi- 

 cal and geological distribution and economical uses, as well 

 as to the literature of the science, this will best be learned 

 from books ; and cannot with advantage form a part of the 

 elementary communications of the Lecturer. The same 

 may be said of the chemical composition of the species ; a 

 kind of information which may be introduced properly 

 enough into an extended course of instruction on the science 

 to which it relates, but, which should wholly be excluded 

 from early lessons on Mineralogy. 



The author trusts that he has not overlooked in his Charac- 

 teristic any well authenticated species of minerals. To 

 avoid this, he has had constantly at hand not only the most re- 

 cent treatises on Mineralogy in English, French, and German, 

 but likewise the Scientific Journals in these Languages, as 

 well as those in Swedish ; and he hopes that as a recent 

 catalogue of mineralogical species, his work may afford 

 some interest to more advanced students than those for 

 whom it was expressly prepared. 



CHARLES U. SHEPARD. 



New Haven, June 1st, 1832. 



