or central track to be added later, and this was built in 1894. It is
supported on columns under the outside tracks, about 43 ft. from center to
center longitudinally and 22 ft. 3 in. from center to center transversely,
the central track being carried by transverse girders between the columns.

The columns carrying the structure are of fan top design, with the points
of bearing near the extremities at the top; each of the outside tracks is
supported on two longitudinal latticed girders and the central track on
two plate girders; between the columns, transverse girders are spliced to
the outside track cross-frames, and carry the central track system. It was
not thought desirable to put brackets on the columns near the street level
to support the structure temporarily, and, as there is an expansion joint
at each column, and as the transverse girders carrying the central track
system are not rigidly attached to the longitudinal girders carrying the
outside tracks, the central track could not be supported by supporting the
outside tracks; therefore, independent supports for each track, in the form
of overhead girders, had to be provided. The columns rest on brick piers,
each having four 2-in. anchor-bolts. The brick foundations on the west side
are wide in order to allow a 24-in. water main to pass directly beneath the
columns. The foundations are usually on rock.

[Illustration: PLATE XLVII, FIG. 1.--TW 4, P.N.Y. & L.I.R.R. Terminal
Station West. View of 9th Ave. looking Northwest from 32nd Street, prior to
commencement of work. April 23, 06.]

[Illustration: PLATE XLVII, FIG. 2.--TW 17, P.N.Y. & L.I.R.R. Terminal
Station West. View of East side of 9th Ave. looking North from a point 100
feet south of 33rd St. showing condition of work. July 23, 06.]

[Illustration: PLATE XLVII, FIG. 3.--TW 25, P.N.Y. & L.I.R.R. Terminal