Nonetheless, all evidence points to mere intent, for nothing has come to light that indicates that a flushing mechanism was in operation or even installed. Nor is there physical evidence to support the intriguing statement from a 1902 publication claiming, "This cellar is said to have had tunnels from it to convey the sewerage out to pits, by earth cars." When the Foundation acquired Monticello in 1923, apparently nothing remained of the Jefferson-period fixtures, and the conversion of the privy shafts into supply and return air ducts for the modern heating and air-conditioning system in 1954 no doubt erased additional evidence. Furthermore, photographs of the tunnel from that time show an earthen floor and not the "slatestone" specified about 1800 for "the sink and for the covered way, kitchen, & offices."
One hypothesis is that the waste was collected in a pot under each seat and then lowered to the cellar level where it could be removed by opening a door in the passage wall. Although today there are openings in the cellar wall for each of the three shafts at a convenient height, the only door that existed before 1954 is for the privy off the first-floor passage. The other two openings were added, according to the restoration architect Milton Grigg, to provide access to the modern ductwork. And given that the partition walls between all three shafts extend as far down as the cellar floor, there is no way one door could serve the adjoining privies. Another hypothesis is that Jefferson adopted a simple routine of having a slave enter the room and remove the chamber pot from under the seat. As for the "sink," it may have functioned as an air tunnel, supplying the shafts with fresh air drawn by a powerful draft through a connecting chimney flue. Of the three interior privies, only the one adjoining Jefferson's chamber was "restored." In 1955, a wooden seat, typical of the period, was installed.