The document discusses three First American tribes - the Aztecs, Mound Builders, and Cliff Dwellers. It notes some artifacts left behind by the Aztecs and Mound Builders, including hieroglyphics, statues, and ceremonial masks and jewelry. The Cliff Dwellers lived in the canyons and mesas of the Southwest near tributaries of the Rio Grande and Colorado Rivers. The author expresses a preference for joining the Mound Builders tribe due to their craftsmanship and friendly nature.