Abstract: An improvement is attained in a cable communication system of the type having communication line incorporated in the interior of a water supply hose which comprises, in combination, signal transmission cable incorporated extending in the interior of the water supply hose for the communication between a water injection nozzle and a fire-engine; a leading end coupling adapter for leading the signal transmission cable incorporated in the water supply hose to the outside for the connection to a communication exchange disposed on the part of the water injection nozzle for communication with the fire-engine and/or a transmitter for the control of the current amount of water to be supplied; and a communication exchange for mutual communication with the water injection nozzle and/or a water supply controller for the control of the current amount of water to be supplied to the nozzle disposed on the part of the fire engine to be connected operative to the signal transmission cable.