Last winter, a contractor was digging a pit for a new septic tank at Baltimore’s Washington Monument, when he hit the edge of a large granite cube. It turned out to be the structure’s long-lost, hollow cornerstone, which contained three glass jars interred in 1815.

“Accounts from the day said there would be coins, newspapers and a likeness of George Washington, but we didn’t know exactly what that meant,” says Lance Humphries, chair of the Mount Vernon Place Conservancy’s monument restoration committee.

The likeness of Washington turned out to be a tiny impression on paper, and the handful of silver, gold and copper coins are now worth around $100,000. The capsule also included a book of Scottish folk songs and a pocket-sized Bible.

Workers also discovered a different time capsule in the monument, which was sealed up in a copper box and placed behind a bronze plaque in 1915. Items from both capsules will be on display at the Maryland Historical Society starting July 4.

The exhibit, called “Treasures Unearthed From Baltimore’s Washington Monument,” will be on view at least through the end of the month, says Mark Letzer, president-elect of the Maryland Historical Society. The exhibit organizers hope it will bring some attention to Baltimore’s Washington Monument, which has long stood in the shadow of the Washington Monument on the National Mall.

“Baltimore’s Washington Monument was the first monument to George Washington,” Humphries says. “At 180 feet, it was an enormous structure when it was completed in 1829, even though it’s not half as tall as Washington, D.C.’s Washington Monument,” which got capped off 55 years later.

Construction on Baltimore’s Washington Monument began soon after the Battle of Baltimore in 1814, which secured the U.S.’s continued independence from England. The contents of the 1815 time capsule show that victory was fresh on their minds.

“The last thing they put in there was a newspaper, which had reprinted the full text of the Declaration of Independence,” Humphries says. “It shows that the Washington Monument symbolized not just George Washington, but American independence, which they had just successfully defended.”

Newspapers made the cut for both time capsules, and they stood up remarkably well despite the damp conditions of the monument, Humphries says. Modern newspapers wouldn’t do so well, he says.

“We certainly thought about putting a copy of the Baltimore Sun back into the cornerstone, but newspapers today are made of such horrible paper that we knew it wouldn’t last,” he says.

Instead, the conservators placed a 3-D printed model of the George Washington statue that sits at the top of the monument and a hollow, 3-D print of Washington’s hand, stuffed with a note explaining what used to be inside the cornerstone.

“Since the original cornerstone had a likeness of Washington, we thought it was important to put a likeness of Washington back inside,” Humphries says.

Maryland Historical Society, 201 West Monument St., Baltimore, opens July 4, $9.

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