Correspondence regarding the operation of various time signals, divided into the following sections:

'Time Signals. General Manager of Telegraphs': correspondence between D. Gill and managers of the Telegraph Department on the operation or failure of the time balls, 1879-1890.

'Time Signal and Clocks at Cape Town Docks': correspondence between D. Gill and the Table Bay Dock and Breakwater Trustees, Cape Town, concerning the operation of the clocks at the dock and the time ball, 1879-1890, including correspondence with Dent and Sons, who manufactured the main clock.

'Time Signal, Simon's Town - Correspondence': reports on defects in the time signals as reported by various ships and the dockyard.

'Time Signal, Port Elizabeth': correspondence between D. Gill and the lighthouse keeper and Telegraph Department at Port Elizabeth on irregularity in the operation of the time signal.

'Time Signal, East London': correspondence regarding the erection and subsequent operation of the Port Elizabeth Time Ball.

'Time Signal, Kimberley': correspondence between D. Gill and the Surveyor-General's Office, Kimberley, concerning the establishment of a time signal there.

'Time Signal, Durban': correspondence on the establishment of a time signal.