2007
TA4116 : WW1 Acoustic Mirror, Kilnsea
taken 20 years ago, near to Kilnsea, East Riding of Yorkshire, England

WW1 Acoustic Mirror, Kilnsea
Rare 4.5 metre high concrete structure near Kilnsea Grange, northwest of Godwin Battery, a relic of the First World War. On the pipe in front of the acoustic mirror was a trumpet-shaped ‘collector head’, a microphone which could pick up the reflected engine sound of Zeppelins approaching from the sea. Wires passed down the pipe to a listener seated in a trench nearby with a stethoscope headset, who would try to determine the distance and bearing of any enemy airships.
