The excavation against the east wall of the American Surety Building was dug by hand. Here two laborers loosen fill as the derrick man prepares to lift a full bucket of spoil. The vertical sheeting and bracing at the north lot line wall reinforces the existing masonry wall and, if the excavation has extended below the original footings, supports fill below the wall. The gentleman with the folding rule, whose head is visible in the foreground, is checking existing conditions or foundation layout against the string line stretched along the western side of the excavation.