The nail holes that related to the ca. 1797 closet framing were found on the sides of the joists framing the ceiling of the Upper North Passage and the Large Bedroom.  By placing a string attached to a plumb bob over the nail hole in the joist and then lowering the string, it was possible to determine where the studs had rested on the floor.  Additional evidence, such as scribe lines and ghosts left where floorwax abutted the baseboards, also helped to determine where the studs were located during the Madison era.