THE 



MONTHLY AMERICAN JOURNAL 



OF 



GEOLOGY 



AND NATURAL SCIENCE. 



Vol. I. Philadelphia, May, 1832. No. 11. 



ON MINERAL AND METALLIC VEINS. 



In fulfilment of the promise made in our March number, we 

 proceed to the investigation of this very curious branch of ge- 

 ology. Our readers will soon perceive the importance of a 

 knowledge of it, in a country possessing such vast metallic re- 

 sources as North America, where indications of them are ap- 

 pearing in such various quarters, and at a period when the ideas 

 entertained respecting their extent and origin are still undefined 

 and obscure, except with those few persons who have made a 

 particular study of the subject. 



It is a very admirable proof of benevolent intentions on the 

 part of the Creator, that iron, without the use of which man 

 could scarcely have achieved his own civilization, is the most 

 abundant of all the metals, and is found, more or less, in all the 

 rocks. Copper and lead are sometimes abundantly found in the 

 strata adjacent to the coal beds, [tabular view, page 388,] but 

 the metals have their principal seat in the primary rocks. They 

 are found disseminated either in extensive masses, or in veins 

 which traverse mineral masses. 



In our paper on the Crust of the Earth, page 289, we spoke of 

 the expansive power by which it was continually agitated, the 

 disturbed state of the lower stratified rocks, and the numerous 

 displacements which constitute so many ancient geological pe- 

 riods. Such a power could not be in operation, without producing 

 extensive fissures, of a character analogous to that we find pre- 

 sented by the numerous veins which traverse the lower parts of 

 the crust of the earth. This has been the probable origin of alt 



Vol. I.— 61 481 



