The information below comes from the above mentioned article by B. Linder.
The Willis Avenue Line as shown for the period of 1934-1941 was a long one at its' peak around the year 1920. Cars ran from Webster and McLean Avenues in the north Bronx and under the 3rd Avenue El for the most part, on Webster Avenue and 3rd Avenue to Willis Avenue.. The line crossed the Harlem River by way of the Willis Avenue Bridge and turned onto East 125th Street. Like most Bronx streetcar lines, the line got its' power from overhead trolley. On 125rh Street between First and Second Avenues, there was a PLOW PIT that allowed the streetcar to change its' motive power from overhead trolley to underground conduit. More about this later. The line traveled west on 125th Street using conduit to 125th Street and 12th Avenue at St. Clair Place which was also known at the Fort Lee Ferry Loop. Important dates are as follows:
- Line started on July 6, 1895 from 133rd Street via Willis Avenue to Melrose Avenue and 161st Street.
- In 1901 a different route was followed from 129th Street and 3rd Avenue to Willis Avenue and 149th Street.
- On April 5, 1916 the long route was established between the Fort Lee Ferry Loop via 125th Street, Willis Avenue Bridge, Willis Avenue, 3rd Avenue, Fordham Road and Webster Avenue to McLean Avenue.
- After 1916, the terminals were changed frequently.
- On March 5, 1920, the service between the Fort Lee Ferry Loop and McLean Avenue was discontinued and the line was cut back from Fort Lee Ferry to Fordham Road only. Shuttles ran between Fordham Road and 3rd Avenue to McLean Avenue.
- On August 18, 1935 buses replaced streetcars north of Fordham Road.
- On August 5, 1941, buses replaced streetcars south of Fordham Road.
From the above review by B. Linder, it seems that Willis Avenue streetcars ran on 125th Street until August 5, 1941, sharing the service with the other lines that ran on 125th Street. When a Willis Avenue car entered Manhattan from the Bronx under trolley wire after crossing the Willis Avenue Bridge, the streetcar would stop at a white line on the street above a plow pit. According to B. Linder, the plow pit was worked by two men. One man in the chamber below and another man on the surface. The westbound Willis Avenue car would have a plow attached in the underground chamber while another man would lower the trolley pole and flip a double-throw switch located in the car. If the switch was at the motorman's end of the car, the motorman would throw it. This work was done very rapidily the the streetcar proceeded west on 125th Street. For Bronx bound cars, the reverse was done where the plow was detached and the trolley pole was raised and the appropriate switches were thrown. This must have been very interesting to see. In the early 1970's, I remember being in an express bus crossing the Willis Avenue Bridge and I remember that some of the tracks were still visible. I am not sure, but I may have seen the shadow of the conduit track even though that portion of the route was under trolley wire. The trackway near the bridge may have been equipped with conduit rail but may have never been used.