During planned renovations on the University of Virginia's (UVA) Rotunda, an architect in charge of the project stumbled across a historic find.

Matt Schiedt, a project manager for John G. Waite Associates, a firm that specialized in historic buildings, explored a strange hole in the wall when examining the Rotunda because he needed to know how thick the walls were, he told The Charlottesville Newsplex.

"I was laying on my back looking up inside this little space. I saw that there was a piece of cut stone which is very unusual to have in this location. You could see that there was a square cut in the stone and that there was a finished space around that with plaster and painted walls," Schiedt said.

What the architect found was a 19th chemistry lab designed by none other than Thomas Jefferson, the nation's first Secretary of State, third President, and UVA's founder. The lab was likely constructed in the 1820s around the time of the Rotunda's completion.

"It adds another aspect to our understanding of the importance of the Rotunda," Brian Hogg, senior historic preservation planner at the University Office of the Architect, told The Daily Cavalier in a statement. "We always focused on the presence and symbolic importance of the library; this illustrates the building's other essential functions."

UVA stated in a news release that Jefferson planned for the lab to be built on the ground floor of the Rotunda to avoid pumping water to higher-level floors and because it was advantageous for experiments.

"Back then, the different experiments would get different levels of heat from different sources," Jody Lahendro, a supervisory historic preservation architect for UVA's Facilities Management, said in the release. "For some, they would put the heat source under a layer of sand to more evenly disperse and temper the heat."