The New York Rapid-transit Subway

Proceedings.] PARSONS ON NEW YORK RAPID-TRANSIT SUBWAY. 29 and the extent of the decoration varies with the relative importance of the stations. At the Borough Hall Station, Brooklyn, the brick wainscot is replaced with marble. In stations of this character adver- tisements on the walls are prohibited. The finished surface of the walls was separated from the main walls by an air-space, for two reasons. Although the exterior wall was waterproofed with great care, the possibility of water leaking through the wall—owing to faults in the original construction, or by the development of a crack through subsequent accidents—was kept in mind. To prevent such a leak from showing on the surface was one purpose of this air-space, as any water passing the exterior wall would find its way down to drains at the bottom. The second purpose was to permit the exposed surface to take the temperature of the air, and not that of the outlying soil, so as to reduce the possibility of condensation. In building the walls, the wainscoting courses were run up to the proper height and set off from the main wall with a clear space of about 1 inch. On the top of the Roman brick a wall of ordinary brick was run up to the height of the cornice, with occasional headers run back, resting against the main wall, to stiffen the interior wall. On the surface of this common brick wall were placed the tiles and mosaic. In building the walls scrupulous care was taken to avoid angles. Intersections between main wall-surfaces were made with curves of large radius, and even the junction between the walls and the platforms was made with curves. This was done in order to facilitate the cleaning of stations, to prevent the chipping of the exposed edges of bricks or tiles, and, in the case of the main wall vertical intersections, to facilitate the passing of passengers. The proper treatment of the ceilings was a matter of much concern. It was finally decided to use white plaster. Within the station-limits the jack-arches over the tracks were plastered with white cement, the plaster being applied directly to the concrete. Over the platforms and in the station-space, except where vault- lights were used, the exposed ceiling was set off from the concrete by an air-space, as in the case of the side walls, the plaster being applied to wire lath. In some cases the jack-arch construction was followed, and in others the ceiling was made flat. The station- lights were placed in recesses in the ceiling-panels. As already explained, the cast-iron columns supporting the roof of the station were set at intervals of 15 feet each. This same interval was accentuated in the roof-design by plaster moulding. The nearness of the platforms to the street-surface, and their situation beneath the foot-pavement, rendered feasible the lighting of