An acoustic listening device developed for the Dutch army as part of air defense systems research between World Wars 1 and 2 (c/o butdoesitfloat)
Posted on Monday, 11 January 2010
Posted on Monday, 11 January 2010
An acoustic listening device developed for the Dutch army as part of air defense systems research between World Wars 1 and 2 (c/o butdoesitfloat)
