On Aug. 28, 1861, a month after the Union Army's disastrous defeat at the first Battle of Bull Run, President Abraham Lincoln sat down and wrote out a Riggs Bank check for $3 to "Mr. Johns (a sick man)."

It is not known who Johns was, where Lincoln encountered him or what prompted the beleaguered president to pause amid the opening weeks of the Civil War to give him a donation.

It is but a tantalizing shard of local history, one of the thousands that reside not in the National Archives or Library of Congress but behind the thick steel door of a 40-year-old basement bank vault in downtown Washington, where the question has become: What to do with them?

The Lincoln check is among a trove of documents gathered over the decades by Washington's venerable and now-defunct Riggs Bank -- which, along with its antecedents, had customers ranging from Davy Crockett to President George H.W. Bush.

The collection includes letters, notes and checks written by, among others, George Washington, Thomas Jefferson, James Madison, Theodore Roosevelt, Eleanor Roosevelt, Dwight Eisenhower, Brigham Young and Gen. John Pershing.

Now, Pittsburgh-based PNC Bank, which took over Riggs on May 13, 2005, is in the midst of a project to gather and inventory the artifacts, which include shelves of crumbling ledgers that go back a century and a half.