A scarce English made ship's radio room clock by Cope of Nottingham. Following the sinking of the Titanic, the Radio Act of 1912 required 24-hour radio watches. The disaster also led to the advent of the radio room clock featuring 3 minute periods marked on the clock face in red. These 3 minute periods indicated radio silence when only emergency radio messages could be transmitted on the 500 kcs. distress frequency. Manual winding facility above 6 and regulation control positioned below 12 also has 2 green 3 minute periods as found on later models. These periods are to allow the monitoring of the 2182 kcs. distress frequency. Each radio room clock also has 4 second red markers to allow the radio room operator to transmit the 4 second alarm signal provided by the 'International Telecommunication Convention' and the 'International Conference on Safety of Life at Sea'. Door missing a small piece of glass, but not torn, see last photo. Original 8-day movement keeps very good time. major diameter: 20cm ensures shipped with track & trace