Mr. Schoolcraft gives this account of a discovery made in West Virginia: “_Antique tube: telescopic device._ In the course of excavations made in 1842 in the easternmost of the three mounds of the Elizabethtown group, several tubes of stone were disclosed, the precise object of which has been the subject of various opinions. The longest measured twelve inches, the shortest eight. Three of them were carved out of steatite, being skillfully cut and polished. The diameter of the tube externally was one inch and four tenths; the bore, eight tenths of an inch. This calibre was continued till within three eighths of an inch of the sight end, when it diminishes to two tenths of an inch. By placing the eye at the diminished end, the extraneous light is shut from the pupil, and distant objects are more clearly discerned.” He points out that the carving and workmanship generally are very superior to Indian pipe carvings, and adds, if this article was a work of the Mound-Builders “intended for a telescopic tube, it is a most interesting relic.” An ancient Peruvian relic, found a few years since, shows the figure of a man wrought in silver, in the act of studying the heavens through such a tube. Similar tubes have been found among relics of the Mound-Builders in Ohio and elsewhere. In Mexico, Captain Dupaix saw sculptured on a peculiar stone structure the figure of a man making use of one. Astronomical devices were sculptured below the figure. This structure he supposed to have been used for observation of the stars. His account of it will be given in the chapter on Mexican and Central American ruins. The Mound-Builders used large quantities of copper such as that taken from the copper beds on Lake Superior, where the extensive mines yield copper, not in the ore, but as pure metal. It exists in those beds in immense masses, in small veins, and in separated lumps of various sizes. The Mound-Builders worked this copper without smelting it. Spots of pure silver are frequently found studding the surface of Lake Superior copper, and appearing as if welded to it, but not alloyed with it. No other copper has this peculiarity; but copper with similar blotches of silver has been dug from the mounds. It was naturally inferred from this fact that the ancient people represented by these antiquities had some knowledge of the art of mining copper which had been used in the copper region of Lake Superior. This inference finally became an ascertained fact. THEIR ANCIENT MINING WORKS.