All street-railway companies within the District of Columbia on January 1, 1902, operating their systems, or parts of their systems, in the City of Washington by use of the tracks of 1 or more of such companies, under a reciprocal trackage agreement, which shall be compelled to discontinue the use of the tracks of another company, shall issue free transfers to their patrons from 1 system to the other at such junctions of their respective lines as may be provided for by the Mayor of the District of Columbia.
D.C. Code § 35-212