Additional evidence for the stair was found on the surviving ca. 1764 studs that framed the stair room.  In this case, the gaps in the plaster ghosts revealed evidence for the stairs stringer and skirt board.   Because wooden trim was commonly installed against the framing before it was plastered in the 18th and early-19th centuries, it is possible to discover where missing pieces of trim were located by looking for interuptions in the plaster ghosts.  In this case, by recording the plaster ghosts on the stair well studs, the Restoration Team was able to determine the approximate size for the both the ca. 1764 stringer and skirt board as well as a rough idea of the stairs slope.  However, to actually build the stair much clearer evidence of the slope would be needed.