An exhibit that traces the development of the nautical chart from classical mythology to satellite imagery will open soon at the Osher Map Library in Portland, Maine. Entitled Charting Neptune’s Realm, the exhibit examines special iconography developed over the centuries to depict the ocean’s attributes, with its ever-changing winds, currents, depths, sea surface temperature, and other transitory features.
Charts on display date to the 16th century, including a 1540 edition of Ptolemy’s Geographia, a world map showing the full 12 winds designated by Aristotle. The 12-wind system remained in use throughout the Middle Ages. In keeping with the mythological origin of winds for direction finding, they are of necessity placed beyond the confines of the known world — beyond earth itself, in an outer, celestial sphere. Also included is one of Ben Franklin’s Gulf Stream charts from 1786.
"The collective experience of seafarers, when linked with advances made in chemistry and physics, produced new interpretations of the world. This knowledge of the sea grew from several simultaneous lines of investigation, sometimes overlapping, sometimes containing large gaps, and even on occasion contradicting one another," said guest curator Donald S. Johnson. "But through the centuries one goal remained constant and undiminished in strength: to bring order out of chaos. Given expression in the form of cartography, these graphic images reveal more succinctly than the written word the knowledge about the watery sector of our globe the ancients called Neptune’s Realm."
Contact the Osher Map Library at 207-780-4850 or visit their web site: www.usm.maine.edu/maps.