Monument record TQ 85 SW 157 - First World War sound mirror, Binbury Manor

Research into acoustic early warning was carried out in a number of countries during the early 20th century. British experiments at the Royal Flying Corps research establishment at Farnborough tested parabolic sound reflectors of varying shapes and curvature, and led to the first true sound mirror being constructed at Binbury Manor by Professor Mather in the summer of 1915. This was a circular disc c. 4.9 m in diameter cut directly into a low chalk cliff. The site, though now ruinous, still survives.

A sound mirror located at Binbury Manor (TQ 811 613). This was Britain's first sound mirror built in 1915 at Binbury, the technical site of Detling aerodrome. Sound mirrors were designed to provide early warning of approaching enemy aircraft by long-distance listening for the sound of their engine. The mirror at Binbury consisted of a circular dish cut directly into a low chalk cliff, with a concave curvature 16ft (4.9m) in diameter. It is unknown when it fell out of use. (1)
The possible site of the First World War sound mirror, cut into a chalk hillside as part of the experimental work of Professor Mather in 1915, is noted in an online history trail around Detling. The position given on the map accompanying the online document may equate to roughly TQ 8116 6063. (2)

<1> Dobinson, C, 2000, Twentieth century fortifications in England, volume 7. Acoustics and radar: England's early warning systems 1915-1945 (Bibliographic reference). SWX23709.

<2> Peter Higginbotham, 2000, The Workhouse (Website). SKE56079.