naval discipline was of great concern.

One of the most widely adopted sounding machines was developed in 1802 by Edward Massey, a clockmaker from Staffordshire. The machine was designed to be fixed to a sounding lead and line. It featured a rotor which turned a dial as the lead sank to the sea floor. On striking the sea floor, the rotor would lock. Massey's sounding machine could then be hauled in and the depth could be read off the dials in fathoms. By 1811, the Royal Navy had purchased 1,750 of