putlog holes
Small holes left in walls for the use of the workmen in erecting their scaffolding: the cross pieces of the scaffold, on which the planks forming the floor are laid, are called “putlogs.” These holes are found in walls of almost every age: they are common in Roman work; Vitruvius calls them “columbaria,” from their resemblance to pigeon-holes. Photo from Monticello, Charlottesville, Virginia, 2023. (Parker, 1896)