My chief object in landing upon the southern shores of Lake Superior, was to visit the places where ancient Indian mining operations had been discovered, in order that I might be, in some degree conversant with matters relating to the origin of the copper ornaments that had been found in some of the burial mounds in Ohio. I also wished to make some excursions into the forests where, amongst the numerous lakes and rivers, the beavers were still constructing their dams and building their lodges. I desired to see something of beaver life and work before the advance of civilisation had removed these forests and beavers away for ever. I obtained convenient quarters in the mining village of Ishpeming, placed in a clearing that had been made in the forest, on the summit of the hills ten miles from the coast. In the interior, within a few miles from the settlement were two rivers called the Carp and the Esconauba. Upon these streams and their connected ponds, the works of the beavers were numerous. They consisted of lodges, dams, canals, excavations, and the open spaces in the forests called beaver meadows. There happened to be an unusually large work constructed across one of the principal bends of the Carp, which by its action in confining the waters had created a small lake. As the size and formation of that dam give a good knowledge of the capacity of the beavers, and their powers of executing works of considerable magnitude, it will be interesting to describe it with some detail. It was two hundred and sixty-two feet in length and nearly six feet high in the centre, where the water was deep. This height diminished gradually towards the banks. The average width upon the top was two feet. The slope outwards was in the direction of the angle which happened to give the utmost resisting power. The base was about fourteen feet wide. The dam was not made in a direct line across the stream, but had curves which were convex towards the current, and were placed at the points of the greatest pressure. The slopes were formed in such a manner that the upper side acted as a barrier against the water, and the opposite side acted as a supporting buttress. [Illustration: BEAVER DAM, LODGE, AND POND, NEAR ISHPEMING, MICHIGAN.] The entire construction was evidently made with a correct knowledge of the strength that was necessary to resist the outward pushing force that was exerted against it. When an engineering work of this nature, so great in proportion to the power and intelligence of its constructors, is examined, and its fitness for the object for which it has been made and for the duty it has to perform, has been ascertained, it occurs to the mind to consider whether such operations are the results of instinct or of some exceptional degree of reasoning faculties.