THE SIGNAL BOX

OVERSEAS

PLAINFIELD
Central Railroad of New Jersey

by John Hinson

Signal gantry at Plainfield
Photograph 1947, from the collection of Dr. J W F Scrimgeour

Plainfield is on the main Jersey City to Allentown line of the Central RR of New Jersey, 24 miles out from Jersey City - near Bound Brook. In this view, a 4-6-0 Camelback locomotive hauling a westbound local train is seen passing the home signals of Plainfield interlocking.

At first glance, there is nothing outstanding about this gantry of signals, but close study reveals otherwise.

All arms appear to be suitable for three-position operation, but this is not the case. These are special lower quadrant signals manufactured by the Union Switch & Signal Company which are provided with two red lenses as well as the usual yellow or green. This was to allow for ice, snow or a faulty motor - if the arm sagged it would still show a red light. Only when fully lowered would it be capable of showing the green or yellow light.

The arms for the two westbound tracks (above the locomotive) have conventional square ends, but those for the eastbound lines have vee ends on the top arms and this may identify them as automatic signals. The lower arms have notches like British distant signals. These signals have a plate attached with a letter P in a circle, and identify the signals as permissive ABS signals, or automatic signals that may be passed at danger under controled conditions. This type of signal was introduced in the 1890's and was widely used until the advent of three-position arms in the 1920's.

Beneath the main arms, subsidiary arms serve the four running lines and a siding alongside, for moves into (or along) the siding.

About the photographs

Additional notes by Mike Brotzman.


Comments about this article should be addressed to John Hinson