Representations of Time and Space on Greco-Roman Timekeeping Devices

DIAGRAMS ACROSS DISCIPLINES: HISTORY, THEORY, PRACTICE

SPEAKER: Alexander R. Jones, Institute for the Study of the Ancient World, New York University 

Two technologies predominated in Greco-Roman timekeeping: sundials, which were static objects exploiting the changing directions of sunlight and shadow, and waterclocks, which translated a controlled flow of water into a display of time. It was characteristic of both technologies to represent both the season of the year and the time of day, measured in hours of seasonally varying length such that the intervals separating sunrise and sunset always comprised twelve equal hours. The grids of "day curves" and "hour curves" featured in varied ways on sundials and mechanized waterclocks were not merely a means of reading off the present date and time, but also a diagrammatic image of the spherical framework of Greek cosmology embedding astronomical definitions of uniform motion and measurable time. 

About the Speaker 

Alexander Jones is Leon Levy Director and Professor of the History of the Exact Sciences in Antiquity at NYU's Institute for the Study of the Ancient World. By training a classicist and historian of science, he takes particular interest in Greco-Roman astrology and astrology, their interactions with broader society as reflected in texts and material objects, and their relations to the astral sciences of other cultures and periods. 

Co-sponsored by the Civilizations of Ancient Greece and Rome Seminar.