H-110. The Art & Science of Cartography, 200–1550

John Hessler

The foundations of modern cartography begin with the researches of the Greek astronomer Claudius Ptolemy in the second century and the re-discovery of his texts in the late Middle Ages and Renaissance. Ptolemy invented the concepts of latitude and longitude and also the idea of a map projection. Early mapmakers used Ptolemy’s ideas and extended them to account for the new discoveries made by explorers in the late fifteenth and early sixteenth centuries. These early modern maps also took full benefit of the developments in mathematics, navigation and astronomy to display the world visually in innovative ways.

Parallel to the tradition of Ptolemy was another and more mysterious form of cartography that appeared around 1250 and died out in the mid-sixteenth century. These maps took the form of a medieval sailing chart and were made for use on board trading vessels that sailed the Mediterranean Sea. Charts like these, called portolans, generally survive as large manuscript maps on vellum and derive from a mapmaking tradition that does not take into account map projections and whose original construction methods still baffle scholars today.

This course will introduce students to the earliest forms of cartography and discuss both the scientific and artistic innovations that made these two kinds of mapmaking possible. We will examine in detail the construction methods of some of the masterpieces of Renaissance cartography, such as the 1507 and 1516 world maps by Martin Waldseemüller, and other examples of early cartography found in the Library of Congress. Students will look closely at the making of portolan charts and take full advantage of new analytical research on their make-up. In addition to close scrutiny of the maps themselves, class discussion and reading will consider medieval and early Renaissance theories of the earth and the relationship of cartography to contemporary developments in astronomy and navigation, as well as the social and cultural aspects of patronage and production.

Late in the course, students will be introduced to digital humanities analysis tools, such as MapAnalyst, and learn to use these new computational methods in order to help date and understand the complex notions of error and knowledge transmission that are at the foundations of modern cartography.

There are no prerequisites for this course, except an interest in early maps and a willingness occasionally to work with and discuss abstract concepts. In their personal statements, applicants should describe the nature of their developing interest in the history of the map, their expectations of the course, and the purposes to which they propose to put the knowledge gained from their participation.

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John Hessler teaches this course.

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John Hessler

John Hessler

John W. Hessler is Curator of the Jay I. Kislak Collection of the Archaeology and History of the Early Americas at the Library of Congress.

A Fellow of the Royal Geographical Society, he is the founder of the Topology Lab for the Study of Mesoamerican and Amazonian Languages, and is on the faculty of the Graduate School of Advanced Studies at Johns Hopkins University, where he teaches classes in computational linguistics, endangered languages and Mesoamerican archaeology. He is the co-director of the Pre-Columbian Society’s Mesoamerican Language, Theory and Decipherment Seminars (known as the Glyph Group) and is the author of more than one hundred articles and books, including Columbus’ Book of Privileges, 1502: the Claiming of a New WorldThe Naming of America: Martin Waldseemüller’s 1507 World Map and the Cosmographiae Introductio; A Renaissance Globemaker’s Toolbox: Johannes Schöner and the Revolution of Modern Science, 1475–1550; Seeing the World Anew: The Radical Vision of Martin Waldseemüller’s 1507 and 1516 World Maps; Galileo’s Starry Messenger and MAP: Exploring the World.

Hessler’s work has been featured in numerous national media outlets including the New York Times, Washington PostDiscover Magazine, and most recently on NPR’s “All Things Considered.” He is currently at work on a book of his collected essays on linguistics and recursion: Searching for Meaning at the Edge of Language (2019).

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