The basement proper was one hundred feet long and forty feet wide with six rooms of varying sizes on either side. The sides of the rooms were stone and abutted the massive stone piers that supported the floors above. With the exception of the two rooms at the western end of the basement, reportedly used for clerical purposes, each side room rose two steps in height from the basement floor. The rooms were dressing rooms for those using the font. The floor was made of red brick laid in a herringbone pattern. The walls were painted white. The floor sloped down to the center of the room to allow water to run toward a drain beneath the font.