On June 25, the Lincoln Memorial Undercroft — a $69 million exhibit underneath the Lincoln Memorial in Washington, DC — opened. The exhibit features rare artifacts, including copies of the Emancipation Proclamation and the U.S. Constitution’s 13th Amendment. And according to City Cast DC reporter Emma Uber, the historic treasures are in danger because of excessive heat.
“The documents — treasured turning points in the nation’s effort to end slavery — date back to the 1860s and are worth millions,” Uber reports in City Cast DC. “But three National Park Service employees, who spoke on the condition of anonymity because they were not authorized to speak publicly, described a facility with faulty security measures. Notably, the employees said, the Park Service has struggled to maintain proper conditions for its rare and delicate documents. Screens designed to shield the records from harsh light have been defective, and temperatures inside the display case have repeatedly reached more than 80 degrees (Fahrenheit), according to the Park Service officials. Experts say that’s a violation of professional standards for housing historic documents and hot enough to accelerate decay.”
According to Katie Lowe of the Conservation Center for Art and Historic Artifacts, historic documents from the 19th Century should never be exposed to temperatures higher than 75F — especially if there is high humidity…