412 071 Metallic Minerals. 



Professor Mitchell considers it to occur as follows:— 



1st. — In veins of quartz, traversing the ancient primitive 

 rocks, in very small quantity. 



2nd — In veins of quartz, traversing more recent primitive 

 rocks, in considerable quantity. 



3d. — In veins of quartz, traversing transition rocks, and 

 also disseminated in considerable quantity. 



4th.— In soil produced by the decomposition of these three 

 kinds of rocks. 



5th. — In the sand of a stream running over old red 

 limestone, in very minute quantity. 



Professor Mitchell is therefore of opinion that the gold 

 is found almost entirely 2« situ. 



Professor Eaton appears to be of the same opinion, and 

 further that it occurs in quartz veins traversing talcose 

 schist : whereas Mitchell considers the rockv matrix to 

 ba an argillate.* 



Mr. Roothe is of opinion that the gold occurs both in 

 situ and alluvium — in the first instance in quartz veins 

 traversing secondary greenstone and greenstone slate. 



The papers containing this controversy are to be found 

 in the 9th, 13th, 16th and 18th vol. of Silliman's Journal. 



NOTE 10. 



" There is a rich lead mine in the township of Potton, 

 adjoining the boundary line between Canada and Vermont. 

 In early times the Indians arc reported to have got loose 

 masses of this lead. It is situated at the base of a bold 



* Such was foiiucrly Professor Olmsted's oiiiuion. 



