On an unseasonably warm day last October in Athens, Greece, a group of Princeton students stepped off the tourist path in the Roman Agora.
As participants in the interdisciplinary seminar “Historical Structures,” co-taught by professors Branko Glišić (civil and environmental engineering) and Samuel Holzman (art and archaeology), these students had received permission from the Greek Ministry of Culture to get a closer look at the remains of an ancient engineering breakthrough.
Builders in ancient Greece had struggled to use stone to span the long distances they needed to create majestic openings between stone columns. In the bushes of the Roman Agora, Holzman and Glišić guided students to the remains of an early, abandoned experiment that used cantilevers to divert weight away from the centers of beams to the supporting columns. These cantilevered beams had been carved around 300 B.C.E. to shade the law courts of ancient Athens. A year earlier, Glišić and Holzman had turned to engineering undergraduate Jonathan Gagnon ’24 to analyze these cantilevers and compare them to a later Greek idea of hiding shallow (flat) arches above the beam.
Using mathematical and computational modeling, Gagnon found out why ancient builders abandoned this first experiment: The cantilevered beams were under more tensile stress than the beams they were relieving. The system of flat arches worked better. Gagnon’s 2024 senior thesis was awarded the Hellenic Studies Senior Thesis Prize and the Frederick Barnard White Prize in Architectural History. He is now an engineer with Guy Nordenson and Associates in New York City and says that one of the great lessons from his time at Princeton was to see engineering as more than a purely technical discipline.
“It is important to have creative ways of approaching what you are doing,” he said. “The hardest problems are the ones that require you to think historically and holistically about the project.” This interdisciplinary approach was the inspiration for Glišić and Holzman’s “Historical Structures” course, which introduces students to engineering and archaeological principles in tandem. The detour in the Roman Agora in their fall 2024 trip was one of many stops at archaeological sites from Delphi to the Peloponnesian peninsula.
