Electric Alarm.
Description:
Patent for a simple and efficient electric alarm to be used for vault protection. It is a magnet, which is a better design than a coil. The magnet is suspended between two points, and a spring that pushes it in one direction. There is an armature that causes friction when it slides, and sounds an alarm when the arm moves in one direction.
Date:
September 3, 1895
Creator:
Hull, William S.
Partner:
UNT Libraries Government Documents Department