Railroad Track Signal

image for Railroad Track Signal
Railroad track signals are part of the control and management infrastructure of train movement. The railroad signal communicates to the operator of the train how to proceed to ensure safe movement. Early fixed signals involved hand signals, flags, and ball signals. With the spread of telegraph lines in the 1850s, train orders could be transmitted quickly from one stop to another. They were followed by automatic systems that developed with the introduction of electricity.
This early type of banner signal, also known as an automatic block signal, was one of the first automatic signals to be used in the United States. It was manufactured by the Union Switch and Signal Company about 1880. The signal operated by a clockworks driven by a 100 lb. weight. The clockworks were set in motion by an electromagnet that was triggered by trains passing over a track-mounted switch.
The signal consists of a box containing a clockwork mechanism. The roof of the box is a vertical spindle upon which are mounted two metal vanes, one painted green with a white striped border, and the other painted red. The box was mounted on a tall hollow iron pole in which the weight that operated the clockwork was suspended. This signal was used on the New York, New Haven & Hartford R.R. until about 1934.
Currently not on view
Credit Line
American Railway Association, Signal Section
See more items in
Work and Industry: Transportation, Railroad
ID Number
catalog number
accession number
used by
New York, New Haven, and Hartford Railroad Company
Union Switch and Signal Company
National Museum of American History
Object Name
Railroad Signal