William Zucker

Certain lines presently used by the IRT were originally built to BMT clearances when it was thought that the then BRT might operate them. This was part of the Triborough System, Proposed and built were the Centre St. Subway, which was part of a proposed loop system to connect all three East River bridges, but the loop itself was never completed; and the Fourth Ave. Subway in Brooklyn, which included a branch to Coney Island via today's West End Line. A branch along Lafayette Ave. in Brooklyn was proposed as a Crosstown Line which was however not built. The lines that ultimately became part of the IRT though built to BMT clearances were the upper portion of the Lexington Ave. Line, including the Pelham Line. Under the Dual Contracts which apportioned lines out to the operating companies, this latter became part of the IRT. To accomodate the narrower IRT cars, metal flanges were added on the platform edges to fill the gap between the platforms and the narrower IRT cars, and this provision can still be seen today. BRT operation would have extended from their Broadway Subway along lower Broadway to 10th St., thence via private right of way, emerging at 14th St. and continuing via Irving Pl. and Lexington Ave., connecting with the existing line north of 42nd St. A portion of the line under Lexington Ave. was actually built between 26th and 40th Sts., as a double deck structure, as with the existing portion further north. After it was determined that the IRT would operate the line from 42nd St. north, construction on this portion was abandoned and the work was filled in and sealed as no longer needed.