Pennsylvania Railroad

by Mike Brotzman

Track Plan

For anyone who knows the line, MIDWAY (MK) interlocking, formerly known as Monmouth Junction, is very aptly named. For anyone not familiar with the North East Corridor, it is very hard to describe exactly what, if anything, MIDWAY lies midway between. MIDWAY is situated along stretch of stretch of near perfectly tangent track in what used to be very rural and is now just typical suburban. It is situated "midway" between the two closest point of importance, New Brunswick to the north and Princeton to the south. The first functional interlocking north of FAIR, MIDWAY is 5.7 miles north of what used to be NASSAU. MIDWAY is the last of the "corridor style" towers to be discussed on these pages and controlled not only a critical full 4-track crossover, but also the junction with the Jamesburg Branch, a freight line.

Webmaster note - I have been informed that Midway is midway between Philadelphia (30th St. Station) and NY City Penn Station. Mile Posts are about 42 miles at Midway and about 90 miles at 30th St Station.

Midway tower
Photograph by Mike Brotzman, 2002

Built in 1944, MIDWAY was the third tower at this location and like the other "corridor style" towers MIDWAY was all brick, had no bay window, red tile peaked roof, internal staircase, interlocking illumination lights and a two column front facade. MIDWAY contained a 35-lever US&S Model 14 electro-pneumatic machine with 20 active levers and controlled brand new 45 mph turnouts and stood to replace the former MK tower with its electro-mechanical machine. Today, MIDWAY is an important crossover point as it is the only interlocking in a 24 mile stretch of high speed track and uses by both express Amtrak and NJT trains that need to access the tracks 1 and 4 platforms at Princeton Junction.

Monmouth Junction station
Photograph by Mike Brotzman, 2002

Here we can see the point of intersection for the Jamesburg Branch and the last attempt at a Monmouth Jct. Station. Previously there existed on this site a wonderful stone station house in the apex of the junction. However, some time between 1953 and 1957 it was torn down and replaced by this utterly repulsive cinderblock and brick shelter. Around 1984, Monmouth Junction was dropped as a station stop.

The Jamesburg Branch was an interesting little stretch of track. The branch proper was about 5.7 miles long and connected the NEC to the parallel Camden and Amboy track. The C&A was one of the original eight railroads in the United States chartered sometime before 1834. It ran from Camden, NJ, up along the Delaware river to Bordentown where it then cut across country to South Amboy, NJ. There the Raritan River flowed out into the Hudson estuary and the Atlantic Ocean. The Jamesburg branch allowed freight trains (namely heavy coal or mineral trains) travelling east on the Trenton Cutoff to access the NEC at MORRIS and then promptly exit the NEC some 18 miles up the track where they could then continue out of everyone's way to the coal and mineral transfer piers in South Amboy. In the mid-1930's, the PRR decided to electrify the branch so that high horsepower electric locomotives could run the heavy trains all the way to the piers. In hindsight, the project provided the lowest return of all the PRR's electrified lines. Oddly enough however, the Jamesburg Branch was the last former Conrail line to loose its heritage PRR overhead wires, the act taking place around 1995. Currently, the Jamesburg Branch is cited to have a key role in the planned NJT M-O-M line to provide passenger commuter rail service to larger parts of Middlesex, Ocean and Monmouth Counties. So far, the main stumbling block to the project has been NIMBY* protests.

* - Not in my back yard!

Midway tower
Photograph by Mike Brotzman, 2002

Here in this wider angle shot we can get a good look at the lever 15 turnout. MIDWAY is still a pneumatic interlocking and you can see that the 45-mph points are powered by 2 cross-linked US&S model A-5 pneumatic switches. The metal shrouds are part of the point heating system for use in colder months. This is the popular "open burner" system used in moderate to heavy snow climates. The system consists of open propane burners that shoot jets of flame right onto the rail near the points, thus heating them and melting the snow and ice. Open burner systems provide fully automatic operation, more heating power than electric resistance systems and less cost and maintenance than forced hot air systems. Also note that the maroon Amtrak MoW truck is still parked next to the tower despite about a year gap between the photos.

This wide angle shot also gives us a better view of a typical PRR substation for its electrified lines. The former PRR lines still run on 12,000 volts AC at 25 Hz. This power is specially generated at a number of locations and then transmitted along the right of way via 4-8 132,000 volt transmission lines hung at the very top of the catenary poles. At each of these substations, usually located at interlockings to consolidate staffing, the voltage is stepped down to 11,000 volts for the overhead wires via enormous transformers, two slightly smaller models are viable here.

One interesting thing about PRR electric motive stock. If there ever came a time when a locomotive needed to be forcibly disconnected from the overhead wire due to some internal electrical fault, the train crews were not permitted to drop the pantograph. Due to the extreme loads, the current would burn through and sever the overhead wire as the pan disconnected. To prevent this, all electric units were equipped with a spring loaded grounding switch that would ground the pantograph to the rail thus having the effect of blowing out the breakers at the section substation to cut off the current. It's hard to tell if this approach was elegant or heavy handed.

About the photographs

Additional information kindly provided by Mike Urbanski

Comments about this article should be addressed to Mike Brotzman