NOTES ON AMERICAN ARCHÆOLOGY.
AUTHOR OF “PRE-HISTORIC NATIONS.”
HARPER & BROTHERS, PUBLISHERS,
John D. Baldwin,
In the Office of the Librarian of Congress, at Washington.
 therefore they are called “Mound-Builders,” this name having been suggested by an important class of their works.
 prepared intelligently, with great labor, for human uses. “Lines of embankment varying from 5 to 30 feet in height, and inclosing from 1 to 50 acres, are very common, while inclosures containing from 100 to 200 acres are not infrequent, and occasional works are found inclosing as many as 400 acres.” Figures 6 and 7 give views of the Hopeton works, four miles north of Chillicothe, Ohio. Combinations of the square and circle are common in these ancient works, and the figures are always perfect. This perfection of the figures proves, as Squier and Davis remark, that “the builders possessed a standard of measurement, and had a means of determining angles.”
tained that the circular inclosures are perfect circles, and the square inclosures perfect squares. They were constructed with a geometrical precision which implies a kind of knowledge in the builders that may be called scientific. Figures 13, 14, 15, 16 show some of the more important works of the Mound-Builders, chiefly in Ohio. Relics of art have been dug from some of the mounds, consisting of a considerable variety of ornaments and implements, made of copper, silver, obsidian, porphyry, and greenstone, finely wrought. There are axes, single and double; adzes, chisels, drills or gravers, lance-heads, knives, bracelets, pendants, beads, and the like, made of copper. There are articles of pottery, elegantly designed and finished; ornaments made of silver, bone, mica from the Alleghanies, and shells from the Gulf of Mexico.