Baltimore's Washington Monument revealed its biggest secret as a contractor was digging a pit for a septic tank.
George Wilk II was overseeing the work in the shadow of the 178-feet column. As the contractor dug six feet into the earth, Wilk spotted the edge of a 2-foot granite cube.
When Wilk saw its bone-white surface and curved edges, he knew it was the monument's long-lost cornerstone — the repository, historians believed, of artifacts left by Baltimore leaders two centuries ago.
"You have to keep an open mind, and you have to listen to what the building has to tell you," said Wilk, project superintendent for Lewis Contractors, the company leading a $5.5 million restoration of the monument. "We weren't willing to go looking for it, but if the building wanted to reveal itself, we were going to accept it."
Wilk joined specialists from the Mount Vernon Place Conservancy and the Walters Art Museum on Wednesday to reveal what the city's forebears sealed inside the hollowed stone.
Their find: Three glass jars, lined with at least three local newspapers, including an edition of Niles' Weekly Register from July 1, 1815.
Under the jars appears to be a copper plaque. The historians can't read the plaque or see inside the jars until they can figure out a way to safely remove them from the 1,000-pound stone.
With the passage of time, the mortar that held the stone's marble lid slid down into the well and bonded the jars together.
"The things are kind of stuck right now," said Terry Drayman-Weisser, a conservation specialist at the Walters. "We have to think about the best way to do this."
Based on descriptions from the ceremony to lay the cornerstone on July 4, 1815, historians believe the jars contain newspapers, coins, an image of George Washington and a copy of his farewell speech.
Once conservationists remove the glass vessels, Drayman-Weisser said, they will put them in thick plastic bags and take them to an X-ray machine at the Walters. She said they will handle the moldy newspapers with care to avoid infecting workers or the art collection.
Water has seeped into the cornerstone, and the newspapers have been freezing and thawing since they were buried, but Drayman-Weisser said they appear to be in pretty good condition. That's in part because newspapers then were printed on paper recycled from cotton, linen or hemp.
"This is really special because these are things that haven't been seen for 200 years," Drayman-Weisser said.
The conservancy, which cares for the monument, has not determined what it will do with the items from the cornerstone, said Lance Humphries, chairman of its restoration committee.
While the stone itself will be returned to its place in the earth, the items might be put on display when the monument reopens during the "Monumental Bicentennial" celebration planned for July 4. Restoration work began a year ago on the monument, which was closed to the public in 2010 after structural problems raised safety concerns.
Workers uncovered a 100-year-old time capsule last fall inside a niche behind a 1915 plaque marking the monument's centennial. The copper box has also been turned over to the Walters, to be opened in May.
It is believed to hold copies of commemorative programs and editions of The Baltimore Sun, which was founded in 1837.
Accounts from 1815 describe the cornerstone-laying ceremony: A reported 30,000 attendees, flush from victory in the War of 1812, turned out for the event at what was then the northern edge of the city.
But no surviving report indicated where the stone was buried.
Wilk, the restoration superintendent, said he thought it might have been laid at the northeast corner of the monument. The placement has Masonic significance, because it's where the sunlight first hits the earth as a new day dawns. (Washington was a Mason.)
Nevertheless, the discovery of the cornerstone last week was unexpected. Contractors were using an excavator to dig a pit for a septic tank, which is needed to accommodate a small bathroom inside the monument's base. No sewer line runs to the site.
Crews spent nearly a week digging the cornerstone out by hand. It took them two more days to carefully chip the lid off the stone.
"You're talking 200 years," Wilk said, and gestured at the hole. "No one knew it was here."
Baltimore Sun research librarian Paul McCardell contributed to this article.
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