When historic Homewood Museum was considering re-wallpapering its drawing room, its conservators turned to a purchased fragment of late 18th-century French wallpaper. The paper would have been made for elegant interior decoration around the same time that Homewood—the original estate of Charles Carroll Jr., which later became the site of the Homewood campus—was constructed in 1801.
However, says director and curator Catherine Rogers Arthur, everyone was in for a surprise when the fragment was removed from its frame by the Sheridan Libraries Department of Conservation and Preservation. Underneath a surrounding border, the wallpaper’s background was light blue, a dramatic difference from the creamy white present in the rest of the fragment that had been exposed to light and air.
“We’re always looking for an opportunity to use Homewood as a learning lab for students,” says Arthur. Seeing the wallpaper’s color discrepancies as a potential student project, she turned to Whiting School Associate Research Professor Patricia McGuiggan, who teaches a class called Materials Characterization. The first half of the semester teaches students different techniques used to analyze various materials, including historical ones. In the class’s second half, students put these techniques to good use in projects with real-world materials.
“These are difficult problems, because students aren’t given pristine samples,” McGuiggan explains. “It’s always a puzzle.”
Because there were two popular blue paints at the time with dramatically different chemical compositions and properties—Prussian blue and ultramarine—McGuiggan tasked students Melanie Shimano ’14, Lucy Oh ’17, and Yu Jung Shin ’17, with figuring out which paint actually composed the wallpaper’s mysterious background color.
The team used six different analytical techniques over the course of several weeks. Eventually, the students concluded that the background paint was ultramarine, providing more realistic information for conservators to reconstruct this wallpaper and to conserve the original fragment for the future.
“The goal for me is to think of Homewood as a research subject on which to impose the scientific method,” says Arthur. “Students are an important part of the research team.”