The ancient monuments of both Americas, are very numerous, indicating a dense population in places since become wild and desolate, as in North America, Guyana, Brazil, &c. They are most numerous in the central parts of both Americas, and lessen towards both ends. Yet they are met from lat. 45 N. to 45 S. They are very variable in different parts; by no means identic, indicating different builders or many degrees of civilization, from the rudest arts to the most refined: employing many materials, earth, clay, gravel, stone, wood, unbaked bricks; being either irregular cyclopian structures, or regular buildings of rough or cut stones, _pizé_ or beaten clay, &c. We do not know as yet one half of those in existence, and many have never been described nor figured. Yet they afford every where, one of the most evident and certain base of historical researches, confirming traditions, or revealing the seats of former empires, their civilization, &c. They consist chiefly in mounds, altars, tumuli or tombs, ruined cities, villages and forts, temples and dwellings; but we find besides in various places, traces of ancient palaces, bridges, roads, causeways, canals, mines, dromes, baths, pyramids, towers, pillars, rocking stones, walls, wells, pits &c. They generally resemble the primitive monuments of the same kind, met with in the eastern hemisphere, from England and Ireland to Mauritania and Africa, extending east to Lybia, Syria, Russia, Persia, Tartary, &c. They have less resemblance with the monuments of Egypt, Greece, Rome, India and China; yet some kinds somewhat assimilate. In fact, there are, throughout both Americas, three very distinct classes of monuments, indicating distinct arts and architecture. The first or rudest, assimilate nearly to those yet used by the rudest tribes in the north or in Brazil, Antilles, &c., indicating a similar barbarous state. The second or primitive, is known by using wood and earth instead of stones for buildings. The third or most refined, employed stones, often well cut as in Mexico, Central America, Peru, &c., and indicates arts nearly equal to those of Egypt and India. Besides such great monumental remains; there are lesser antiquities; fragments of sculpture, statues, idols, painting, Mosaic, &c., either in metals, stones, pottery, beads, &c., found every where mixed with the others.