Note 89 — ARCHITECTURAL HISTORY AND DESCRIPTION: THE MANSION HOUSE
Reading edition
Ibid. The location of this masonry wall in the basement and its extension upward to the second floor made it possible for the original house to have the floor joists set lengthwise with the house instead of front-to-back. The joists were thus anchored in the outside walls at each end of the house and in the center wall running midway through the house.