At the Kingston Penitentiary the three wings containing cell blocks, as well as one other wing, converged in a rotunda. This round central area, similar to that envisioned by Bentham in his Panopticon, was topped with a glass dome serving as a source of light and ventilation and as a lookout from which guards could watch the prison yard. Stoves like the one in the lower left provided heat to the cell blocks by means of long pipes. At night, prisoners entered the rotunda on different levels and descended, by iron staircases, to the main floor where they were issued tea and bread. The room was completely open and free of recesses where prisoners might avoid observation. As the inmates entered, were given rations, and were marched back to the cell blocks, guards could easily supervise them from a central vantage point.
