young people annoy you?

From a newsbrief in the December 12, 2005 issue of Chemical & Engineering News, the journal of the American Chemical Society, there is now a device that is designed to “shoo away” teenagers. The device, invented by Howard Stapleton, emits a high-frequency pulsing sound that almost everyone under 20 and virtually no one over 30 can hear. Designed to keep young people from hanging out outside of…

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