The latest discovery at the President's House dig near Independence Hall is startling not just for what it is, but for where it is.
An old wall that was part of George Washington's original office has been found just to the east of the viewing platform at the dig.
Edward Lawler Jr. is an historian with the Independence Hall Association:
"Robert Morris builds this three-story bathing room off the side of the house in 1782, and Washington has the bathtubs taken out of the second floor and turns it into his private office."
Incredibly, he says, Washington's office shared that wall with the hidden underground passageway that archaeologists believe was used mostly by the president's enslaved Africans:
"That is where he would have met with his cabinet, that is where he would have signed legislation from Congress into law, that is where he met with his generals and planned military strategy. It's where the president performed the day-to-day business of the nation."
The dig continues through at least July 4th week. Lawler wonders what will happen after that:
"The idea of putting all the dirt back and never seeing these artifacts again, I think — I hope — is no longer being considered."