A uniform code of signals for working winches in mines was established in 1887. Signs displaying the signals had to be placed in clear view of the engine driver and at each level of the mine. The signals were various numbers of bells.A metal sign with a black background and red and white printing. There three sections, the top one is white text, Signals for Winding, numbered 1 to 10 and 15 down the sign, with instructions next to each number. The next section is red text, Firing Signals, with two lines numbers and writing. The third section is white text, Interplat Signals with signals to raise or lower cage to various levels.code of signals, underground minning