The Future Is Here
We may earn a commission from links on this page

Thomas Jefferson’s Lost Chemistry Lab Found Hidden Behind Wall

We may earn a commission from links on this page.

Conservators working at the University of Virginia’s Rotunda have inadvertently uncovered a chemical hearth designed by Thomas Jefferson. The discovery is offering fresh insights into how chemistry was taught over 200 years ago.

The iconic Rotunda, constructed in 1826, is located on The Lawn of the original grounds of the University of Virginia and is currently undergoing renovations. Inspired by the Pantheon in Rome, Thomas Jefferson designed it to symbolize the “authority of nature and power of reason” and the separation of church and education.


Credit: Aaron Josephson/Public domain.

Back in 1895, a fire destroyed much of the building’s interior. But during the 1850s, the chemical hearth—part of an early chemistry classroom—was sealed in one of the lower-floor walls of the Rotunda, which protected it from the fire. Recently, while preparing for the current renovations, workers examining the cavities in the walls unexpectedly discovered the lost chemistry hearth.


Back in Jefferson’s day, chemistry was taught on the Rotunda’s bottom floor. His collaborator, professor of natural history John Emmet, taught the classes. UVA Today explains how it worked:

The chemical hearth was built as a semi-circular niche in the north end of the Lower East Oval Room. Two fireboxes provided heat (one burning wood for fuel, the other burning coal), underground brick tunnels fed fresh air to fireboxes and workstations, and flues carried away the fumes and smoke. Students worked at five workstations cut into stone countertops.

Brian Hogg, senior historic preservation planner in the Office of the Architect for the University, said the chemical hearth may have been for Emmet’s use; the students may have had portable hearths with which they conducted experiments.

“Back then, the different experiments would get different levels of heat from different sources,” said Jody Lahendro, a supervisory historic preservation architect for U.Va.’s

Facilities Management. “For some, they would put the heat source under a layer of sand to more evenly disperse and temper the heat.”

According to Hogg, this may be the oldest intact example of early chemical education in the United States.


The University of Virginia will put the chemical hearth on display once renovations are complete.

[ University of Virginia ]

Email the author at and follow him at @dvorsky. Images: Dan Addison.