THE ORIGIN of this book will explain its intention and character. It reprints, with suitable revision, a series of fourteen articles written for The Geographical Magazine ( London) at the desire of its Editor, and published between July 1953 and August 1956. It is designed chiefly as a picture book, and not as a systematic history of exploration. The chapters, which are grouped in a rough regional order, present some episodes and phases in the history of geographical discovery for which the evidence of contemporary maps is specially interesting or accessible. The treatment is therefore selective, and may seem arbitrary; but the dominant themes have not been ignored.
The book may be regarded as a pictorial companion to general histories of exploration (some of which are listed on page 328). The maps used or drawn by explorers describe the borderland between the known and the unknown. Their evidence may tell us what a traveller expected to find or what he in fact discovered. They may have the authority of a prophecy, of a prospectus, or of a chronicle. In early maps information derived from theory and from experience is often inextricably entangled, and for this very reason they are important documents in the history both of geographical ideas and of geographical discovery. They illustrate the always shifting 'relation of observation, theory, and practice' in this field of science.
The recording of an itinerary or a journey is one of the oldest uses which maps have served, but systematic survey and map- or chart-work in connection with voyages of discovery are scarcely found before the 15th century. This is strictly the chronological starting-point of the book. The first chapter, written as a pièce d'occasion for the 700th anniversary of Marco Polo's birth, defines some of the motives and objectives by which explorers from the 15th to the 18th centuries were prompted.
The text is planned as a concise summary of geographical ideas and events associated with the maps reproduced. It contains little that is original, and much that