MOUND-BUILDERS AND PLATYCNEMISM IN MICHIGAN. 385 



feet ill diameter; some being quite sliallow, while many reacli a depth 

 of from twenty to sixty feet. They are scattered throughout the island, 

 wherever the amygdaloid copper-bearing rock is found, and are ii)vari- 

 ably on the richest veins; great intelligence being displayed in locating 

 and tracing the veins and in following them up when interrupted, &c. 

 To quote from my paper, "This has elicited the astonishment of all who 

 have witnessed it — no mistakes apparently having been made in this 

 respect. The excavations are connected under ground, drains being 

 cut in the rock to carry off" the water. Stopes one hundred feet in length 

 are found. A drain sixty feet long presented some interesting features; 

 Iiaving been cut through the surface-drift into the rock, it had evidently 

 been covered for its entire length by timbers' felled and laid across. 

 When opened, the timbers had mostly decayed, and the center portions 

 Lad sunk into the cavity, filling it for nearly its entire length with the 

 rotted wood." The amount of mining on three sections of land, at a 

 point on the north side of the island, is estimated to exceed that of one 

 of our oldest mines on the south shore of Lake Superior, "a mine 

 wiiich has been constantly worked with a large force for over twenty 

 years." When we compare the tedious methods of the primitive 

 miners, and all the disadvantages under which they must have labored, 

 with our modern improvements in mining appliances and all our 

 resources, this may well appear almost incredible. 



At another point the excavations extend, in nearly a continuous line, 

 for more than two miles, the pits being often "so close together as 

 barely to permit their convenient working. Even the rocky islets off" 

 the coast have not escaped observation, and where bearing veins of 

 copper are generally worked." But it is probable that, including all 

 the discoveries, not one-tenth of the excavations have been disclosed. 



"The method of mining pursued by this people was, evidently, on 

 turning back the overlying drift, to heat the rock by the application of 

 fire; then, when by dashing on water the rock was sufficiently disinte- 

 grated, to break and pulverize it with their great hammers." The rude 

 stone-ha,mmers or mauls, weighing from ten to thirty pounds, are found 

 in suiprising quantities. With this exception no tools of stone have 

 been observed. A large part of a wooden bowl, originally about three 

 feet in diameter, which had probably been used for bailing water, was 

 taken from one of the pits. Fragments of charcoal abound. The tools 

 formed of copper consist principally of chisels and knives. Arrow-heads 

 of the same material are frequently collected. 



Having seen the remark that the copper tools of the " ancient miners" 

 are of rough and not polished exterior, inferences being drawn there- 

 from as to their rude construction, I wish to say that, having examined 

 a large number of the tools, I believe this roughness to have been 

 mostly caused by corrosion. In many cases this is quite palpable, the 

 original surface being apparent in i)laces, and evidently confirming the 

 i'act that at least the external faces of the tool were originally approx- 

 imately SMnooth, if not polished. 

 25 s 



