Legends of Atlantis — Brasseur de Bourbourg’s Theory — The Subject Examined in the Light of Science — Retzius’ View — Le Plongeon’s Observations — Identity of European and American Plant Types — Revelations of the _Dolphin_ and _Challenger_ Expeditions — The Atlantic Floor — Challenger and Dolphin Ridges — “Challenger Plateau” probably once Dry Land — Identity of European and South American Fauna — Elevation and Depression of Coast Level — Of Greenland, the United States, and South America — The Gulf Stream — Equatorial Current — The Trade-Winds — Accidental Discovery of Brazil — America Probably Reached by Ancient Navigators — The Caras — Atolls of the Pacific Ocean — A Pacific Continent — Contiguity of the Continents at the North — Aleutian Islands — The Kuro-Suvo — Behring’s Straits — Inviting Appearance of the American Shore — Remoteness of the Migration — Prof. Grote’s View — Prof. Asa Gray’s Observations — Conditions Favorable to a Migration — Mr. John H. Becker’s Observations. CHAPTER XII. CONCLUSION APPENDIX. A. MADISONVILLE EXPLORATIONS. B. ELEPHANT PIPE. C. CHARNAY EXPLORATION. D. HOUSE ARCHITECTURE OF THE MOUND-BUILDERS AND PUEBLOS. INDEX THE NORTH-AMERICANS OF ANTIQUITY. CHAPTER I. ANCIENT INHABITANTS OF THE UNITED STATES. The Aborigines — Antiquity of the Red Indian — The Mound-builders — Geographical Distribution of Mound-works — Frontier Defences of the Mound-builders — Michigan Mounds — Mounds in the North-west — On the Upper Missouri — In Dakota — Animal Mounds of Wisconsin — Elephant Mound — Discoveries at Davenport, Iowa — Davenport Tablet — Heart of the Mound-builder Country — Cahokia — Resemblances to Mexico — St. Louis and Cincinnati Works — Cincinnati Tablet — Works in Ohio — Fortified Places — Fort Ancient — Signal Systems — Works at Newark — The Ohio Valley — Explorations in Tennessee — Burial in Stone Coffins — Mound Colonies in the South-east — Mr. Anderson’s Calendar Stone — Mounds of the Lower Mississippi Valley — Seltzertown Mound — Alabama and Georgia Mounds — Pyramid of Kolee-Mokee — Explorations in Missouri — Sun-dried Bricks — Remains in the South-west — Direction of the Migration — Architectural Progress — Altar Mounds — Mounds of Sepulture — Ancient Copper Mines — Astronomical Knowledge.