80,000: cost in $US of four LRADs (long-range acoustic devices) purchased by the Austin, Texas, police department between 2011 and 2016
1743: the year Jean-Antoine Nollet, French Catholic abbot and scientist, “confirmed that sound carried in water”
100: more than that number of U.S. cities “have put some restriction on gas-powered leaf blowers”
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¹Footnotes
LRAD: [austinchronicle.com](https://www.austinchronicle.com/news/2022-07-29/questions-arise-about-apds-use-of-sound-machines/). Nollet: [nautil.us](https://nautil.us/swimming-in-noise-22162/). Blowers: [dallasobserver.com](https://www.dallasobserver.com/news/should-dallas-ban-gas-powered-leaf-blowers-12746919 )
*Originally published in the August 1, 2022, edition of the This Week in Sound email newsletter. Get it in your inbox via [tinyletter.com/disquiet](https://tinyletter.com/disquiet).*