528 APPENDIX. 



The mass of copper is so situated as to afford but little that 

 would enable us to judge of its original geological position. In 

 examining the eastern fork of the river, I discovered small water- 

 worn masses of trap-rock, in which were specks of imbedded 

 carbonate of copper and copper black ; and with them were occa- 

 sionally associated minute specks of serpentine, in some respects 

 resembling that which is attached to the large mass of copper ; 

 and facts would lead us to infer that the trap formation which 

 appears on Lake Superior east of the Ontonagon River, crosses 

 this section of country at or near the source of that river, and at 

 length forms one of the spurs of the Porcupine Mountains. 



Several smaller masses of insulated native copper have been 

 discovered on the borders of Lake Superior, but that upon On- 

 tonagon River is the only one which is now known to remain. 



At as early a period as before the American Revolution, an 

 English mining company directed their operations to the country 

 bordering on Lake Superior, and Ontonagon River was one point 

 to which their attention was immediately directed. Traces of a 

 shaft, sunk in the clay hill, near a mass of copper, are still visi- 

 ble — a memento of ignorance and folly. 



Operations were also commenced on the southern shore of Lake 

 Superior, near the mouth of a small stream, which, from that 

 circumstance, is called Miners' River. Parts of the names of the 

 miners, carved upon the sandstone rock at the mouth of the river, 

 are still visible. What circumstance led to the selection of this 

 spot does not now appear. No mineral traces are at this day 

 perceptible, except occasional discolorations of the sandstone rock 

 by what is apparently a mixture of the carbonates of iron and 

 copper ; and this is only to be observed where water, holding in 

 solution an extremely minute portion of these salts, has trickled 

 slowly over those rocks. • 



It does not, in fact, appear that the red sandstone, which con- 

 stitutes the principal rock formation of the southern shore of 

 Lake Superior, is in any instance metalliferous in any considera- 

 ble degree. If this be true, it would require but little reflection 

 to convince one of the inexpediency of conducting mining opera- 

 tions at either of the points selected for that purpose; and it is 

 beyond a doubt true, that the company did not receive the least 

 inducement to continue their labors. 



