A large number of discs or medals of copper have been obtained from the mounds. They resemble, to use a familiar illustration, the bosses observed on harnesses. Some of these are not less than two inches, but most are about one inch and a half in diameter. They are formed of thin plates of copper, are perfectly round, and concavo-convex in shape. They are found only on the altar-mounds, where they seem to have been placed with their edges together, in pairs. Owing to the great heat to which they have been subjected, and subsequent oxydation, nearly all of them are so cemented together that they cannot be separated without breaking them into fragments. Their present appearance is very well exhibited by Fig. 91. Some of them, of more elaborate workmanship than the rest, and which have been more favorably situated for preservation, have been separated.[132]
Fig. 92.
These articles, it will be observed, display more skill in working the metal, than any of those previously noticed. They present every appearance of having been pressed into shape, in the way in which similar articles are formed at this day. In opening one of the mounds, a block of compact sandstone was discovered, p207 Fig. 92, in which were several circular depressions, in all respects resembling those in the work-blocks of copper-smiths, in which plates of metal are hammered to give them convexity. These depressions are of various dimensions, and are evidently artificial. It seems more than probable it was in such moulds that these articles were formed. This block weighs between thirty and forty pounds.
Fig. 93.
Fig. 94.
Small tubes of copper, formed by wrapping together thin slips of that metal, are often found. They are not soldered, and though the edges overlap each other very closely, they can easily be separated with the blade of a knife. They were doubtless strung as beads. Another variety of beads, made of coarse copper wire, closely wound and hammered together, are occasionally found.
Among the articles that exhibit the greatest degree of skill in their manufacture, may be mentioned a sort of boss or button, several of which are shown in the engraving. These present a convex and a plane surface, and are identical in form with some of the old-fashioned buttons which still linger on the small clothes of our grandfathers. They are hollow; a portion of them are perforated from the sides, but most have the holes through which passed the thread, by which they were strung or attached, in the base. They bear a resemblance to some forms of the ancient fibulæ.