Prehistoric man

by Sir Daniel Wilson

The mining operations of upwards of a quarter of a century have done much to efface the traces of the ancient works, as every indication of them is eagerly followed up by the modern miner, as the most promising clew to rich metalliferous deposits. But towards the close of 1874 Mr. Davis, an experienced old miner of Lake Superior, recovered from another ancient trench, in the same region, a solid mass of nearly pure copper, heart-shaped, and weighing between two and three tons. It lay at a depth of seventeen feet from the surface, as when originally detached from its bed by the ancient miners. Alongside of it were a number of smaller pieces, from a single ounce to seventeen pounds in weight, evidently broken off the large mass by the original workers of the mine. Numerous stone mauls and hammers also, weighing from ten to thirty pounds, lay scattered through the lower débris with which the trench was refilled. But the absence of any copper tools seemed to point to the final desertion of the mine, from some unknown cause, at the very time when its resources were most available.

Attention was first directed to such traces of ancient mining operations, by the agent of the Minnesota Mining Company in 1847. Following up the indications of a continuous depression in the soil, he came at length to a cavern where he found several porcupines had fixed their quarters for hybernation; but detecting evidences of artificial excavation, he proceeded to clear out the accumulated soil, and not only exposed to view a vein of copper, but found in the rubbish numerous stone mauls and hammers of the ancient workmen. Subsequent observation brought to light excavations of great extent, frequently from twenty-five to thirty feet deep, and scattered over an area of several miles. The rubbish taken from these is piled up in mounds alongside; while the trenches have been gradually refilled with soil and decaying vegetable matter gathered through the long centuries since their desertion; and over all, the giants of the forest have grown, withered, and fallen to decay. Mr. Knapp, the agent of the Minnesota Company, counted 395 annular rings on a hemlock-tree, which grew on one of the mounds of earth thrown out of an ancient mine. Mr. Foster also notes the great size and age of a pine-stump which must have grown and died since the works were deserted; and Mr. Whittlesey not only refers to living trees upwards of three hundred years old, now flourishing in the abandoned trenches; but he adds: “on the same spot there are the decayed trunks of a preceding generation or generations of trees that have arrived at maturity and fallen down from old age.” The deserted mines are found at numerous points extending over upwards of a hundred miles along the southern shore of the lake; and reappear beyond it, in extensive excavations on Isle Royale. Sir William Logan reports others observed by him on the summit of a ridge at Maimanse, on the north shore, where the old excavations are surrounded by broken pieces of vein-stone, with stone mauls rudely formed from natural boulders. The extensive area over which such works have thus been traced, the evidences of their prolonged working, and of their still longer abandonment, all combine to force upon the mind convictions of their remote antiquity.

At Ontonagon river I met with Captain Peck, a settler whose long residence in the country has afforded him many opportunities of noting the evidences of its ancient occupation. Repeated discoveries had led him to infer the great antiquity of the works; and he specially referred to one disclosure of ancient mining operations near the forks of the Ontonagon river, where, at a depth of upwards of twenty-five feet, stone mauls and other tools were found in contact with a copper vein; in the soil above these lay the trunk of a large cedar, and over all grew a hemlock-tree, with its roots spread entirely above the fallen cedar, in the accumulated soil with which the trench was filled, and indicating a growth of not less than three centuries. But the buried cedar, which in favourable circumstances is far more durable than the oak, represents another and longer succession of centuries, subsequent to that protracted period during which the deserted trench was slowly filled up with accumulations of many winters. In another excavation a bed of clay had been formed above the ancient flooring to the depth of a foot. On this lay the skeleton of a deer which had stumbled in and perished there; and over it clay, leaves, sand, and gravel had accumulated to a depth of nineteen feet. Not only are such indications frequent throughout the Keweenaw Peninsula, and to the westward and southward of Ontonagon; but on Isle Royale the abandoned mines disclose still stronger evidence of their great antiquity. The United States Geologists remark: “Mr. E. G. Shaw pointed out to us similar evidences of mining on Isle Royale, which can be traced lengthways for the distance of a mile. On opening one of these pits, which had become filled up, he found the mine had been worked through the solid rock, to the depth of nine feet, the walls being perfectly smooth. At the bottom he found a vein of native copper eighteen inches thick, including a sheet of pure copper lying against the foot-wall.” Stone hammers and wedges lay in great abundance at the bottom of the trenches, but no metallic implements were found: a proof perhaps that the mines of Isle Royale continued to be wrought after their workers had been hastily compelled to abandon those on the mainland. Mr. Shaw adopted the conclusion, from the appearance of the wall-rocks, the multitude of stone implements, and the material removed, that the labour of excavating the rock must have been performed solely with such instruments, with the aid, perhaps, of fire. But the appearance of the vein, and the extent of the workings, furnished evidence not only of great and protracted labour, but also of the use of other tools than those of stone. Accumulated vegetable matter had refilled the excavations to a level with the surrounding surface, and over this the forest extended with the same luxuriance as on the natural soil. In this barren and rocky region the filling up of the trenches with vegetable soil must have been the work of many centuries; so that the whole aspect of the deserted mines of Isle Royale confirms the antiquity ascribed to them.

What appear to the eye of the traveller as the giants of the primeval forest, are the growth of comparatively modern centuries, subsequent to the era when the shores of Lake Superior rang with the echoes of industrial toil. Two or three centuries would seem altogether inadequate to furnish the requisite time for the most partial accumulation of soil and decayed vegetable matter with which the old miners’ trenches have been filled. Four centuries thereafter are indisputably recorded by recent survivors of the forest, independent of all traces of previous arborescent generations; and thus in the excavations and tools of the copper regions of Lake Superior, we look on memorials of a metallurgic industry long prior to those closing years of the fifteenth century, in which the mineral wealth of the New World awoke the Spanish lust for gold. An uncertain, yet considerable interval must be assumed between the abandonment of those ancient works, and the forest’s earliest growth; and thus we are thrown back, at latest, into centuries corresponding to Europe’s mediæval era for a period to which to assign those singularly interesting traces of a lost American civilisation.

Owing to the filling up of the abandoned mining trenches with water, not only the copper and stone implements of the miners are found, but examples of wooden tools and timber framing have also been preserved, in several cases in wonderful perfection; and these furnish interesting supplementary evidence of the character of their industrial arts.

Fig. 63.—Miners’ Shovels.

Of the wooden implements, the most noticeable are the shovels, by means of which the soil was excavated. The accompanying woodcut represents two of them worn away to the one side, as in most of the examples found, as if used for scraping rather than digging the soil. Mr. Whittlesey gives a drawing of one which measured three and a half feet long, recovered among the loose materials thrown out from an extensive rock excavation in the side of a hill about four miles south-east of Eagle Harbour. Part of a wooden bowl used for baling water, and troughs of cedar-bark, were also found in the same débris, above which grew a birch about two feet in diameter, with its lower roots scarcely reaching through the ancient rubbish to the depth at which those relics lay. Mr. Foster describes another wooden bowl found at a depth of ten feet, in clearing out some ancient workings opened by the agent of the Forest Mine; and which, from the splintered pieces of rock and gravel imbedded in its rim, must have been employed in baling water. Similar implements have been met with in other workings, but they speedily perish on being exposed to the air. All of them appear to have been made of white cedar. The indestructible nature of this wood, when kept under water, or in a moist soil, is abundantly illustrated by the experience of settlers who, on attempting to clear and cultivate a cedar swamp, discover that the dead trunks, exhumed undecayed after centuries of immersion, rest above still older cedar-forests, seemingly unaffected by the influences which restore alike the oak and the pine to the vegetable mould of the forest soil.

Fig. 64.—Miners’ Stone Mauls.