The winds in the margins of the world, from one of the first books on navigation, Pedro de Medina's Arte de Nauegar (Cordova, 1545). Medina reportedly traveled with Cortés and was later entrusted by the king of Spain with the examination of pilots and sailing masters for the West Indies. The world shown here is just taking shape at the edges as voyages of discovery increase knowledge.

This map appears on the homepage of the map collection's website ("http://icg.Harvard.edu/~maps/"), where it nicely emblemizes what the staff intends to achieve: the meshing of a vast resource of maps on paper with maps and mapmaking capabilities available through digital technologies. Use of the collection by people who come in the door has doubled in almost every recent year, says David Cobb, head of the collection. It isn't only the digital maps that bring them; they pore over the historical paper record preserved in steel cases.

City Plans. Left: A detail from one of the 21 plates in Michel Turgot's large-format atlas Plan de Paris (Paris, 1739), Louis Bretez, cartographer. Notre Dame cathedral appears at upper left. The Seine is alive with boats. An axonometric view, this is fine draftsmanship for a man without a helicopter. "It is one of the great city views and shows the primacy of French cartography in the period," says Tom Conley, professor of Romance languages and literatures.

Conley teaches and writes on issues related to his convictions that the advent of widely available maps--which rapidly became the basis of statehood, of the management of property, of taxation--revolutionized the way people formed mental images of space, and that one cannot understand early modern writing in the absence of a grip on that point. He calls the map collection "one of the great gems of the world" and cites it and Harvard's rare book library as two points that define his earthly paradise.