› added 2 years ago

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TIL that Emery is the third form of Corundum, after Sapphire and Ruby, is what Emery Boards are made of, and has been mined in Greece since antiquity.

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via reddit.com

l78ZB TIL that the heart of Washington DC in the mid-19th Century was a literal open sewer
GYGD7 TIL a circle is used to represent a city on a map since early maps would draw small bird's-eye views of cities, and walled cities during that time were usually circular. Eventually the drawing was dropped and only the circular outline remained.
168YD TIL of the Double-slit experiment. Reality is weird
YKbB TIL The singing voices of Homer, Apu, Barney, and Skinner in The Simpsons episode “Homer’s Barbershop Quartet” were provided by Disneyland’s The Dapper Dans
vmlK TIL strangling and choking are not the same thing. Strangling cuts off blood flow through the neck, while choking cuts off air flow.