This book is produced from the catalog of a recent exhibition of portolan maps long held by The National Library of France. The word "portolan" is an abbreviated Italian adjective which means "related to ports". Portolan charts were developed in the 12th century by both famous and anonymous ocean-going and (obviously) coasting voyagers. They are, "foremost, a spider web of fine lines radiating from focal points on the map's background. In short, it's an abstract schematic over which coastal outlines are superimposed and which are labeled in perpendicular fashion with names of ports, harbors, capes and islands." (The library holds some 500 of these maps, a collection of exceptional quality, many having an abundance of gold decorations and ornamentations.)

The business end of these amazing documents--navigation-- is impressive enough, considering the absence of knowledge of the entire world at the time. But it is the medieval mode of pictorial expression, known as "illumination" applied to sacred texts that can be equated to the decorations and illustrations that adorn these maps (in a much more informal and less elaborate form than those on religious tracts) that is so fascinating.

Originally drawn on parchment, portolans documented or proposed the travels of European voyagers on the vast uncharted waters of the Atlantic, Indian Ocean, and eventually, the explorers of the Pacific, including Balboa, Magellan and others.

The catalog is divided into five sections. The forward includes a description of the library's impressive collection written by the library's president, followed by scholarly remarks which suggest that, due to the elaborateness of the decoration (gold was sometimes used), they were often left behind so that sponsors and relatives could follow the proposed journey from home. Another brief essay examines the collectability of such rare and fragile wonders, and describes how portolan maps were made and used.

The rest of this 256 page (11x10.2x1.5inch) master compilation divides the world into geographically distinct parts known to the original map makers. The section titled Mediterranean "refers to the manufacture and use of the first charts, centered on and the persistence of this tradition in the Mediterranean basin until the 18th century".

The second section, The Open Sea, "shows how these regional charts have evolved from a technical and iconographical point of view at the time of the great European voyages, in order to include the oceans and new worlds.

The third part, The Indian Ocean, "shows how these charts, in a maritime area where ancient civilizations coexisted, were dependent on other cartographic traditions (ancient, Arab, Asian) before joining the information reported by Portuguese sailors and European trading companies in the modern era."

What unfolds in this fascination volume of medieval illustration is the sense of wonder and amazement expressed by the early maritime explorers as they encountered hitherto unknown plants, creatures and civilizations. The text, provided by the scholars is necessary to the understanding of the maps and the scenes but one's imagination can get lost in the medieval world presented by this book.