ANCIENT MINING ON THE SHORES OF LAKE SUPERIOR.
In the month of March, 1848, Samuel O. Knapp and J.B. Townsend discovered, from tracks in the snow, that a hedgehog had taken up his winter-quarters in a cavity of a ledge of rocks, about twelve miles from Ontonagon, Lake Superior, in the neighborhood of the Minnesota Copper Mine. In order to capture their game, they procured a pick and shovel, and commenced an excavation by removing the vegetable mould and rubbish that had accumulated about the mouth of what proved to be a small cavern in the rock. At the depth of a few feet they discovered numerous stone hammers or mauls; and they saw that the cavern was not a natural one, but had been worked out by human agency, and that the stone implements, found in great profusion in and about it, were the tools used in making the excavation. Further examination developed a well-defined vein of native copper running through the rock; and it was evidently with a view of getting this metal that this extensive opening had been made.
This was the first instance where "ancient diggings"—as they are familiarly called in the Lake Superior region—were ever recognized as such; and this artificial cavern presents the most conclusive proofs that a people in the remote past worked those mines. Upon the discovery of this mine, attention was at once directed to numerous other cavities and depressions in the surface of the earth at this and other points, and the result was that nearly a hundred ancient pits were found, and in all of them mining-tools of various kinds. These ancient mines or pits are not restricted to one locality, but extend over the entire length of the copper region, from the eastern extremity of Keweenaw Point to the Porcupine Mountains, a distance of nearly one hundred miles.
In some of the ancient diggings, the stone hammers have the marks of hard usage, fractured or battered faces, and a large proportion of them are broken and unfit for use; but in other pits the hammers are all sound, and many of them have the appearance of never having been used. These hammers, or mauls, which are of various sizes, and not uniform in shape, are water-worn stones, of great hardness, similar in all respects to those that are found in abundance on the shore of the Lake, or in the gravel-banks of that region. They are generally trap-rock, embracing the varieties of gray, porphyritic, hornblendic, sienitic, and amygdaloidal trap, and appear to have had no labor expended upon them except the chiselling of a groove around the middle for the purpose of attaching a withe to serve as a handle. In a few instances, I have noticed small hammers, usually egg-shaped, without a groove; and the battered or worn appearance at one end was all that induced the belief that they were ever used for hammering.
These hammers are usually from six to eight inches in length, and from eight to twelve inches in circumference, and weigh from four to eight pounds; but I have measured specimens that were twenty-four inches in circumference at the groove, and would weigh thirty pounds. It seems hardly probable that one man could wield so ponderous a tool; and from the fact that some of the large mauls have two grooves around them, it is presumed that two men were employed in using them.
Stone hammers are found in all the ancient diggings, and in some instances the number is almost incredible. From the pits near the Minnesota mines it is estimated that ten cart-loads have been removed; I was informed that a well there was entirely stoned up with them, and from the great number still remaining I am inclined to believe the report. A still greater number are said to have been found at the Mesnard and Pontiac Mines, in the Portage Lake district. Farther east, in the vicinity of the Cliff and Central Mines, they are also abundant; and it would seem, from the circumstance of their being invariably found in the pits, that the law among the ancient miners was similar to the one adopted by the adventurers in California a few years since, who established their claims by leaving their tools upon the land or in the pits where they were digging for gold.
In addition to the stone implements, copper chisels, wedges, or "gads," are often found in the abandoned mines; and in the vicinity, as well as in places more remote, other copper relics are found, consisting of knives, spear-points, and rings, like the bracelets of the present day. In a collection at the Douglas House, in Houghton, Portage Lake, are ornaments of this kind, and also some spear-heads, nicely wrought and similar in shape and size to the blade of a spontoon. But I have never seen a copper relic that had the appearance of having been melted. They invariably appear to have been cut and hammered into shape from a mass of native copper.
Colonel Charles Whittlesey, of Cleveland, Ohio, who has examined these "ancient diggings," has several interesting relics, some of which he has figured and described in the thirteenth volume of the "Smithsonian Contributions to Knowledge." In the Vermont State Cabinet is a spear-head of native copper, about six inches long, which was found in Williston, Vermont, in 1843.
It may be proper here to remark, that the copper in these relics is tougher than that which has been fused, and so is the native copper of Lake Superior; and occasionally in these copper relics blotches and grains of native silver are found. These circumstances serve to establish the fact, that the material of which the implements were made was obtained at Lake Superior; for there, and nowhere else in America, is native silver found in grains, and sometimes in considerable masses, imbedded in a matrix of native copper. I well remember, when a boy, reading an article relating to the "Lost Arts," in which the fact was stated, that a piece of metal consisting of pure copper and silver had been found in Hamilton County, Ohio, and that a copper knife had been found in one of the ancient mounds at Marietta, which had distinct blotches of pure silver in it. The writer of the article claimed that the people who manufactured that knife were in the possession of an art, now lost, by which copper and silver could be melted and indiscriminately mixed, but upon cooling would separate and remain distinct and pure, instead of forming an alloy. The discovery of native copper and silver similarly associated in the Lake Superior mines has not only destroyed this theory, but has established beyond a doubt the locality whence that copper knife, and other relics found in the ancient mounds and elsewhere, were obtained.