Signalrammers

Signalrammers are a type of mechanical signaling device used historically on railways to control train movements. They consist of a long pole with one or more colored discs or lanterns attached. These discs or lanterns can be rotated or pivoted into different positions to convey specific signals to train crews. The primary purpose of a signalrammer was to indicate whether a section of track was clear or occupied, and to control the speed or movement of approaching trains.

The design of signalrammers varied, but they generally operated through a system of levers and pulleys operated from a ground-level cabin or post. A signalman would manipulate these controls to change the position of the discs or lanterns, thereby altering the signal displayed. For instance, a horizontal disc might indicate stop, while a diagonally inclined disc could signify caution. During nighttime operations, lanterns would be used, with different colored lights (typically red, green, and white) representing the same meanings as the daytime discs.

Signalrammers were a crucial element of early railway safety systems before the widespread adoption of electrical signaling. Their simplicity and mechanical nature made them relatively reliable in various weather conditions. However, they also had limitations, including visibility issues in fog or heavy snow, and the need for a physical presence at each signal location. Over time, more advanced and automated signaling technologies replaced signalrammers on most railway networks.