Pratt's original plans have been lost, but extensive notes on his intentions have survived. On each of the two main floors he placed identical apartments about square at the four corners, each with two square closets at their outer end. This provided flexibility of use for the rooms. Two of the inner closets housed servants' stairs. The two ends of the bedroom floor were connected by a balcony supported by columns which may have served the additional purpose of helping support the north side of the cupola.