Description: Patent for an attachment to railroad safety signal boards that holds orders for trains in a box that only opens when the danger or stop signal is raised on the semaphore. To get the clear signal, the orders must be replaced in the box or put on a clip on the outside of the box, which rings an alarm while they are there to alert the railroad operator to reset the box.
Date: February 26, 1907
Creator: Gates, William Thomas
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department