PREFACE. Xin 



Such is a sketch of what has heretofore been done for the promotion of Minera- 

 logy in this State. I have been desirous not only to embody in this volume the 

 facts which have been collected during the progress of the Survey, but to post 

 up all the information that was previously possessed in regard to it. With this 

 view, I have consulted all the American books and periodicals which were 

 thought to contain any thing on this subject. Adhering scrupulously to the prin- 

 ciple which I have uniformly adopted, I have given due credit for every impor- 

 tant fact which has been thus introduced ; and to afford those who may be desi- 

 rous of consulting original papers, the opportunity of doing so, I have, in nearly 

 all cases, given the references in full. 



It remains for me to present my acknowledgments for the assistance which 

 I have received during the prosecution of this work. I have already, in my 

 several annual reports, noticed such gentlemen in various j^arts of the State as 

 afforded facilities in the collection or study of our minerals. To them I again 

 tender my thanks. It is an act of justice to state, that I am under great obliga- 

 tions to Dr, William Horton, who for three years was my assistant. From 

 this gentleman I have constantly received important aid in nearly every depart- 

 ment of the work entrusted to me. For the original observations which he has 

 from time to time furnished, I have given him credit under the appropriate 

 heads. 



From Dr. Emmons, of the Survey, I have received many favours, such as the 

 loan of interesting specimens for notice and description, and of several maps and 

 cuts. Indeed, it will be seen by an examination of this volume, that I am greatly 

 indebted to all the geologists for interesting facts in regard to the mineralogy of 

 the districts which they examined. 



Nor should -I omit to state, that for the careful supervision of these sheets as 

 they passed through the press, my thanks are due to Mr. John Patterson, of 

 the State Printer's Office. His scientific attainments have admirably quahfied 

 him for labours, the value of which can only be fully appreciated by those who 

 have had the experience of publishing a work of this kind. 



