The study of early maps and atlases has in recent years engaged the interest of an increasing number of scholars from a variety of disciplines. A small but dedicated group of professional geographers has been concerned with the origins and development of geographical thought and knowledge, including the representation of geographical data on maps and charts. Professional historians have devoted their attention to the period of discoveries and the cartographic revolution it induced. Others with this specialization have chronicled the unrolling of the map of the United States as the trans-Mississippi country was explored and surveyed in the nineteenth century. Library of Congress specialists have, through the years, compiled comprehensive cartobibliographies and prepared scholarly studies relating to the history of cartography. Because of their permanent reference value and to make them available in a convenient format to a wider audience, the papers are reprinted in this volume. Individually the selections provide detailed information about a number of unique or distinctive early maps and atlases. Collectively the papers illuminate many fascinating milestones and landmarks along the evolutionary trail of cartographic history.