APPENDIX. 537 



The entire area may be estimated to comprise a rocky, serrated 

 coast of about seventy-five miles in length, and not to exceed 

 seven or eight miles in width. The principal veins arc at a point 

 called Eochc Verd, and along the coast which we refer to as the 

 Black Eocks. At the latter, native copper is one of the constitu- 

 ents of the vein. 



Green and blue carbonate of copper was also observed in limited 

 quantity, in small rounded masses, at one of the lead diggings 

 near Mineral Point, Iowa County. 



87. Cheomate of iron. Presque Isle, Lake Superior. 



38. SuLPHURET OF LEAD. Lead mines of Iowa County, Michi- 

 gan Territor}^. 



39. Earthy carbonate of lead. Brigham's mine, Iowa 

 County, Mich. Ter. Also, in small masses, of a yellowish white, 

 dirty color, and great comparative weight, at several of the lead 

 mines (diggings) in the more westerly and southern parts of the 

 county. 



4. Geological Outline of the Taquimenon Valley of Lahc Superior. 

 By Henry E. Schoolcraft. 



The Eiver Takquimenon originates on a plateau between the 

 northern shores of Lake Michic-an and the southeastern coast of 

 Lake Superior. At a central point on this plateau, there lies a 

 lake of moderate size, which, in the translated Indian phrase, is 

 called Heartsblood Lake. A little to the west of this lake, and, 

 perhaps, connected with it, originates the head stream of the 

 North Manistic Eiver of Lake Michigan, running southwest. 

 Towards the northeast the Takwymenon takes its way, winding 

 through level grassy plains, till it reaches the rim of the geo- 

 logical basin that circumscribes Lake Superior. The height of 

 this point is conjectural. It is probably one hundred and fifty 

 feet above the level of the lake. 



To comprehend the geography of the region, it is necessary to 

 advert to the fact that the sandstone formation, which appears in 

 the picturesque form of the Pictured Eocks, is last seen in its 

 range eastward at La Pointe des Grrande Sable, where its surface 

 is of a compact structure and dull red color. Between this 



