20ft and 30ft Sound Mirrors, Denge
Shot of the 20ft and 30 ft sound mirrors at Denge. The spectacular remnants of a dead-end technology, the three "listening ears" at Denge near Dungeness in Kent are the best known of the various acoustic mirrors built along Britain's coast. A forerunner of radar, the sound mirrors were intended to provide evidence of enemy aeroplanes (or airships) approaching Britain. The 30' dish still has the metal pole which a microphone would have been fixed to. The mirror worked by focusing the noise of aircraft engines onto the microphone, which amplified the sound. The relatively slow aircraft of the time could be heard and located before they came into sight.
Size: 3872px × 2653px
Location: Denge, Dungerness, Kent, UK
Photo credit: © John Gaffen 2 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: acoustic, aircraft, boffins, concrete, dead-, denge, detector, device, distance, dungerness, early, ears, intelligence, kent, listening, long, military, millitary, mirror, mirrors, physics, redundant, reinforced, science, secret, sound, technology, top, warning, wartime
