These Acoustic listening devices were developed for the Dutch army as part of air defense systems research between World Wars 1 and 2. Made me look! Oh my!
These Acoustic listening devices were developed for the Dutch army as part of air defense systems research between World Wars 1 and 2. Made me look! Oh my!
I’d really love to hear what they sound like.
Dec 17th, 2009 / 9:36 am
Brilliant! I wonder how successful they were. Or if they were the equivalent of two huge sea shells.
Dec 17th, 2009 / 9:44 am
this is related to the sound mirrors in the uk, forerunner of the radar. really impressive stuff ! http://bit.ly/5VViZj
Dec 22nd, 2009 / 11:01 am
No wonder we got beat-up in high-school.
Dec 22nd, 2009 / 4:52 pm
Oh yes, my collegue needs these.
Dec 24th, 2009 / 3:52 pm