■ g A \ < ' 1 i: N T M 1 N I N G 



responding group of rude trenches, showing the position of the veins, for more than 

 two miles. The ground rises gradual!} to a height of 631 feet ahove the lake, but 

 on the south drops suddenly off into a deep valley. The Ontonagon Rivei cuts the 

 range two and a half miles wesl of the mine, being navigable for batteaux to the 



Landing. 



In the ahove section, across the main lode, 1 have grouped together several 

 remarkable objects, that were seen near each other, though not strictly in contact. 

 The descriptions and sketches are in part due to Mr. Knapp, partly to Messrs. Foster 

 and Whitney, and also to m\ personal examinations. 



The vein Ii B has a variable thickness from one to nine feet, dipping northerly, at 

 an angle of about 60° with the horizon. This is somewhat steeper than the dip of 

 the strata, or wall rock, A A. On some of the veins, the excavations extend east- 

 ward, out of the Minnesota, into the grounds of the Rockland Mining Company, 

 when- tluv are very distinct. Being upon the southerly slope of the mountain, the 

 ditches have become very much filled up by washing from the surface. The greatesl 

 depth of the ancient excavation is thirty feet. At the place of the above section 

 the vein had been removed to a depth of twenty-six feet. 



Not far below the apparent bottom of a trough-like cavity where shaft No. am is 

 aow situated, among a mass of leaves, sticks, and water^Mr. Knapp discovered a 

 detached mass of copper weighing nearly six tons. It lay upon a cob work of round 

 logs or skids six to eight inches in diameter, the ends of which showed plainly the 

 strokes of a small axe or cutting tool about 2* inches wide. These marks were 

 perfectlj distinct. A piece of this wood which I took from the mine in 18-49 proved 

 to be a species of oak, the only species known upon the range, and by some called 

 the Spanish oak. It shrunk on drying to about two-thirds of its size, cracking open 

 in deep gashes, and possessed little strength. Its appearance was that of water- 

 soaked timber not rotted, preserving its original form. 



The mass of copper had been raised several feet along the foot wall of the lode. 

 on the timbers, by means of wedges. Its upper surface and edges were beaten and 

 pounded smooth, all the irregularities taken off, and around the outside a rim or lip 

 was formed, bending downwards. This work had apparently been done after the 

 miners had concluded to abandon the mass. Such copper as could he separated by 

 their tools was thus broken off. The beaten surface was smooth and polished, not 

 rough. Near it were found, as the excavation advanced, other masses. // //, imbedded 

 in the vein. After several years, this vein has been found by the modern miners 

 uncommonly rich and valuable for the size and number of its masses of copper. 



Not far to the west of this spot a portion of the vein a a had been left like a 

 pillar as a support to the hanging wall, while they excavated beneath. It is cut or 

 bruised quite smooth, but shows no marks of other tools than the mauls. This 

 rocky support is about four feet in thickness, mid is high enough above the present 

 bottom of the trench to allow a person to pass under it. The marks of fire on the 

 mcks of the w alls are still evident. ( 'harcoal, ashes, and stone mauls are found in all 

 of the pits hitherto cleaned out. One of the heaviest mauls yet seen, weighing thirty- 

 six pounds, came from this location. It has ;i double groove, as shown in the annexed 

 figure, which is not usual, and it, was intended, no doubt, to be used by two men. 



