AIR OF NEW YORK SUBWAY—SOPER. 649 
By the contract for construction we learn that it was intended, 
when the road was designed, that it should be easily accessible, light, 
dry, clean, and well ventilated. It was largely to accomplish these 
ends that the road was built as close to the surface of the streets as 
physical conditions permitted. 
Much care was taken to make the subway dry. It was declared to 
be the “ very essence of the specifications ” for construction to secure 
a structure which should be entirely free from the inward percolation 
of ground or outside water. 
The roof of the subway was so close to the level of the streets that it 
was possible for the builders to make extensive use of vault lights for 
illuminating the stations with natural light. Full advantage was 
taken of the possibilities in this direction. The area of the vault 
lights at some stations was so great that little artificial hight was 
employed, excepting at night. 
Incandescent lamps were the only artificial lights used except for 
signals. 
Provisions for cleanliness—In constructing the road, provisions 
for keeping the subway clean were carefully carried out at the sta- 
tions. The passenger platforms were made of cement and the walls 
of tile, the joints and moldings being such as to permit of easy clean- 
ing. The stairways were supplied with safety treads, which collected 
much street dirt, thus keeping it from entering the subway. f 
Provision was made in the original design for a concrete roadbed, 
which would have enabled the road to be kept clean between stations; 
but modifications in the contract, after it was let, resulted in the con- 
struction of a broken stone roadbed, from which only comparatively 
large particles of refuse could be removed. 
The subway was ventilated through the stairways at the stations 
and through blow holes in the roof. Exchanges of air between the 
subway and streets took place chiefly by reason of the movement 
of trains. 
The subway was about 50 feet wide and 18 feet high on the four- 
track section between Brooklyn Bridge and Ninety-sixth street, and 
the cross section of a car occupied about 14 per cent of this subway 
section. The trains were from 150 feet to 408 feet long. 
The number of passengers in the cars varied somewhat at different 
hours of the day, but the cars were usually crowded. There were 
fifty-two seats in each car, and when the aisles and platforms were 
filled the total number of passengers per car ranged from about 115 
to 140. The densest crowding occurred in the rush hours when people 
were going to and from their work and throughout the length of 
that portion of the subway which was selected for closest observation. 
The number of cars per train, the number of trains per hour, and 
the speed varied at different hours. The local trains usually con- 
