MOUND-BUILDERS AND PLATYCNEMISM IN MICHIGAN. 380 



this last-mentioned landing appear to have been improved by artifi- 

 cial means. It is 20 feet wide by about 60 feet in length, and has 

 a gradual slope to the lake, the rock being generally smooth through- 

 out. On each side are perpendicular walls of rock. Small boats 

 could easily be hauled out here, particularly with the aid of timbers 

 laid for the purpose. Near it, and all along it, wherever there are 

 indications of copper- veins, are the circular pits of the "ancient mi- 

 ners." Though of small size, (from 2 to 5 feet in diameter and about as 

 many feet deep,) they are remarkably -distinct. At this place the rock is 

 mostly as level as the floor of a room, and the well-like pits are imme- 

 diately perceived to be the work of human agency. 



Though the pits were carefully searched, no relics were met with, 

 other than the angular fragments of the rock, broken off by the usual 

 methods pursued by those rude miners. The fragments occasionally 

 contained copper. 



One of the small pits, a little OT«r two feet in diameter and nearly 

 two feet deep, had a large, irregular slab of rock covering its mouth. It 

 required two men to remove this. We found the pit more than half-full 

 of the angular fragments above alluded to, ranging from less than a 

 cubic inch up to more than two^ubic inches in size. From the indica- 

 tions we hoped to find this the repository of some valuable relics ; but, 

 though the hole was emptied of its contents, nothing other than already 

 mentioned was encountered. Had any tools or other utensils been 

 deposited here as a place of safety, they had long since disappeared ; 

 probably decaying through the lapse of ages. From appearances, and 

 the isolated character of the island, I am inclined to think that my 

 hands were the first to touch these objects since the departure of the 

 primitive workmen. 



At two places, at each end of the circular i^its, the copper- veins in the 

 wall-like cliff had been attacked and partly excavated. The rock was 

 discolored as if from the action of fire, and at the base of the more cen- 

 tral point the sandstone was considerably hollowed. All those works 

 exhibit the same roughish surface, totally unlike that produced by the 

 action of water. 



Immediately at the end of the southern landing, already described, is 

 a marked depression, occupying nearly the center of the island, and 

 presenting some indications of artificial origin. But about 35 feet 

 northwestward of the head of the landing occurs a more remarkable 

 excavation. This is of rectangular form, 25 feet by 20 feet, and with 

 an average depth of nearly four feet. It is filled with water, as are the 

 pits. The sketches already referred to [Figs. 11 and 12] supply such 

 further information as I was able to obtain. 



It may not be uninteresting to state, in this connection, that I found 

 the rare fern, Botrycliium hinaria, Swartz., flourishing, and rather abun- 

 dant on the exposed rock of this island. It grew i" tufts of PotentiUa 

 tridentata, Ait., grass, and other dwarfed plants. 



