A Lecture by Dr. Stephen C. McCluskey
R. S. Webster National Lectureship**
Archaeological Institute of America

Monday, November 14, 2011
Nunemaker Auditorium
Monroe Hall, 3rd floor
8 pm
free admission and free parking on campus
Co-sponsored by the Office of the Provost, the Classical Studies program and the New Orleans Society of the Archaeological Institute of America

It is a commonplace that in the Middle Ages the Christian church – as an institution – was the primary center of education, including education in the sciences. Less well known is the fact that Christian churches – as physical structures – embodied and portrayed elements of astronomical learning in a way that was accessible to, and used by the general populace.
This astronomical learning was practical in focus and concerned areas where astronomy intersected with the ritual and practical concerns of medieval society with the organization of time and space. Medieval people expressed two principal aspects of time in the construction and decoration of their churches: the time of year and the time of day.
Churches provide two different expressions of the time of the year. One, which only becomes apparent from the examination of large groups of churches, is the practice of orienting churches to face sunrise at the time of the vernal equinox, which was traditionally believed to be the time of Creation. More easily seen, but perhaps not so easily recognized by modern observers, are the many depictions of the signs of the zodiac and the corresponding labors of the months, which reflect the influence of the annual apparent motion of the Sun through the signs of the zodiac upon the changes of the seasons.
Since antiquity, the ability to measure the changing time of day by observing the motion of the Sun was seen as separating man from the beasts. Clerics and layfolk needed to know the times to pray, so it is not surprising that a range of sundials of varying degrees of complexity adorn medieval churches. With the development of mechanical timekeepers these also found their place in medieval churches. Some were simple timekeepers, but others went beyond mere timekeeping to provide models of the cosmos, displaying the motions of the Sun, Moon, and planets, the changing time of Easter and even the times of solar and lunar eclipses. As mechanical timekeepers came to display the regular passage of time, a simpler, but more precise, form of astronomical timekeeper emerged to synchronize these manmade timekeepers with the machina mundi, the machine of the universe. These meridian lines marked the passage of the Sun directly to the south to identify the moment of noon.
We are familiar with the notion that the religious imagery that adorned medieval churches served as books in stone and paint and glass and provided a way to teach medieval people religious lessons. The astronomical elements embodied in medieval churches complemented this religious imagery by teaching the basic astronomical relations of space and time.
Dr. McKluskey is Professor Emeritus of History at West Virginia University.
He holds a PhD in the History of Science from the University of Wisconsin. He is currently Co-editor for Archaeoastronomy: The Journal of Astronomy in Culture (Univ. of Texas Pr.) 1998-present and until recently has served as Chair for the Working Group on the Preservation of Astronomical Heritage of the American Astronomical Society. He has published copiously on the topics of astromony and cosmology ranging from Native American cultures to monasteries and churches of the Medieval period.

**In 1998, Mrs. Marjorie Webster of Winnetka, Illinois, established an endowment to support AIA lectures in memory of her husband, Roderick S. Webster (1915-1997), former Curator and Chairman of the Board of the Adler Planetarium in Chicago, Illinois. Roderick and Marjorie Webster first came to the Adler Planetarium in 1962 as volunteer supervisors of the scientific instrument collection, which was formed in 1930 when Max Adler founded the Adler Planetarium & Astronomy Museum and purchased approximately 500 astronomical, navigational, and mathematical instruments from Anton Mensing in the Netherlands. In 1969 the Websters were appointed Co-Curators, and in 1991 they became Curators Emeriti. During their tenure, they traveled widely to study collections of scientific instruments and turned the Adler's Webster Institute for the History of Astronomy, which today contains more than 2000 instruments and models from the 12th through the 20th centuries, into the largest collection of such material in the Western Hemisphere and one of the most significant in the world. The Webster Institute is also home to an outstanding library of rare and modern books, a collection of works on paper, and the Adler Planetarium's Institutional Archives.
Marjorie Webster continues to be Curator Emerita at the Webster Institute for the History of Astronomy. She received her education in archaeology at Sarah Lawrence College and the University of California at Berkeley.
R. S. Webster Lecturers are chosen by the Lecture Program Committee of the AIA.

Christ in majesty surrounded by the zodiac and the labors of the months. Central tymapanum of the west portal of the Abbey Church of Sainte-Madeleine, Vézelay, France (early 12th. c.).