the outer window bays consist of one window per floor, and the inner bays contain two windows per floor. Between each floor are terracotta spandrels, which are recessed behind the piers. Each bay is separated by three-quarter piers that rise from the fourth to the fifteenth stories. There are iron balconies on the 14th floor. At the 15th floor, the piers end in foliated capitals, and the tops of the windows end in elaborate arches. The 16th floor serves as another "transitional story" and its windows are surrounded by complex ornamentation. A cornice runs above the 16th floor. The crown comprises the 17th through 20th floors. The 17th through 19th floors are designed as a triple-height arcade. The spandrels between the floors are decorated with multicolored floral motifs, while there is another ornate cornice above the 19th floor. On the 20th floor, there are groupings of two windows in the outer bays and three windows in the inner bays, with an elaborate colonette. There are figures of griffins separating each window bay. The top three stories consist of a copper-clad mansard roof. There are dormer screens containing small balconies on the 21st floor, while the 22nd and 23rd floors contain dormer windows. These windows are covered by polygonal dormer roofs. Above the 23rd floor is an asphalt roof surface containing mechanical equipment as well as bulkheads. The dormers, as well as decorative tourelles, added to the aesthetic of the building when it was originally viewed from the waterfront. Foundation The site was difficult to develop, as the bedrock layer was an average of below the ground level of the site. The ground above the bedrock was composed of of clay directly above, then a layer of sand, and finally of mud and silt at ground level. Construction was further hindered by the difficulties in constructing caissons due to the frequent fires and air-pressure-related injuries associated with such structures. Gunvald Aus, the structural engineer, dismissed the original plans for the foundation, which called for the usage of pneumatic caissons so that the foundation would be deep inside the rock. Instead, he decided to use pilings because he felt that it was sufficient for the layers of rock and hardpan to be immediately adjacent. Pilings had been previously used in two other Lower Manhattan buildings: the New York Produce Exchange and the Havemeyer Building. The foundation consisted of pilings that descended at