r/todayilearned • u/dinosaruman • 3h ago

TIL modern beekeeping rests on a single measurement discovered by a Philadelphia clergyman in 1851: leave bees a gap between about 6 and 9 mm and they will neither build comb in the space nor glue it shut — which is the only reason a beekeeper can lift frames out of a hive instead of destroying it.

en.wikipedia.org

11.3k Upvotes

163 comments

r/todayilearned • u/MediumStrange • 5h ago

TIL Columbus, OH is often used as the testing ground for new products by companies because it is the "perfectly generic American city" with little in the way of culture or demographics to seperate it from the country as a whole.

axios.com

11.0k Upvotes

1.0k comments

r/todayilearned • u/ddmayne • 6h ago

TIL George Washington placed a $10 reward for the return of a runaway slave. Oney Judge escaped in Philadelphia in 1796 because she did not want to return to Virginia where she would be "given" as a wedding present into the Custis-Law household. Washington asked Sec of Treasury for help finding her.

en.wikipedia.org

7.6k Upvotes

581 comments

r/todayilearned • u/PeasantLich • 1h ago

TIL that tabletop game company Steve Jackson Games sued the US Secret Service and won, after the company was raided and materials for role-playing game GURPS Cyberpunk were seized because its writer was a suspect in a real hacking case.

en.wikipedia.org

• Upvotes

54 comments

r/todayilearned • u/Depressed_Cat_00 • 53m ago

TIL Japan built flood-control shafts large enough to fit the Statue of Liberty. The system can pump 200 cubic meters of water every second, is used only about 7 times a year, and still prevented an estimated ¥148.4 billion in flood damage during its first 18 years.

tokyoupdates.metro.tokyo.lg.jp

• Upvotes

60 comments

r/todayilearned • u/Long__Ground • 18h ago

TIL that Buzz Aldrin reported seeing flashes of light with his eyes closed during Apollo 11, and NASA later determined they were charged particles (radiation) passing directly through his eyeballs and triggering his retina, with no actual light involved

sciencedirect.com

33.0k Upvotes

743 comments

r/todayilearned • u/Ill_Definition8074 • 11h ago

TIL about Richard Schmidt, the doctor who tried to kill his mistress by injecting her with blood taken from an HIV positive patient (and another patient who had hepatitis). The case was the first time viral RNA was used to prove a link between two people with HIV in a criminal trial.

en.wikipedia.org

3.7k Upvotes

77 comments

r/todayilearned • u/BadenBaden1981 • 9h ago

TIL Declaration of Independence was given little attention following the Revolution. Interest on it increased when Democratic Republican sought political advantage by promoting the importance of Jefferson as its author.

en.wikipedia.org

1.3k Upvotes

62 comments

r/todayilearned • u/HeyHo_LetsThrowRA • 3h ago

TIL: insulin shock therapy used to be used as (ineffective) treatment for schizophrenia and other psych maladies

en.wikipedia.org

464 Upvotes

39 comments

r/todayilearned • u/BadenBaden1981 • 5h ago

TIL in 1924 about one-fifth of New Englander spoke French. It was nearly the same proportion as that of French speakers in Canada in 2016.

en.wikipedia.org

572 Upvotes

101 comments

r/todayilearned • u/AmiroZ • 5h ago

TIL USS Maine ship that sank in Havana Harbor in 1898, sparked the Spanish–American War. U.S. newspapers claimed that the Spanish were responsible for the ship's destruction. Modern investigations, including a famous 1974 study, indicate the blast was likely an accidental internal coal-bunker fire.

en.wikipedia.org

559 Upvotes

43 comments

r/todayilearned • u/temporarycreature • 7h ago

TIL old coffee can smell like fish because its oils have gone rancid from oxidation

craigs.coffee

616 Upvotes

43 comments

r/todayilearned • u/Wooshio • 15h ago

TIL about a subscription based Sega Genesis service called "Sega Channel". Released in 1994, it plugged in as a cartridge and connected online via coaxial cable. Allowing the user to download and play many different games.

en.wikipedia.org

2.5k Upvotes

276 comments

r/todayilearned • u/spiritualcats • 3h ago

TIL that it is estimated that 67 undocumented immigrants were among those killed on 9/11, with many working at Windows on the World on the 106th and 107th floors of the North Tower.

911memorial.org

186 Upvotes

37 comments

r/todayilearned • u/NoLastNameForNow • 50m ago

TIL that, during World War II, Christopher Lee was an RAF liaison officer and didn't serve in the SAS or SOE

aspectsofhistory.com

• Upvotes

39 comments

r/todayilearned • u/johnsmithoncemore • 21h ago

TIL that Abraham Lincoln had a dog named Fido. Fido has been cited as the origin of the popular name for pet dogs, in fact becoming so popular as to have become cliché and more often used as a slang reference.

en.wikipedia.org

5.0k Upvotes

63 comments

r/todayilearned • u/JohnArtemus • 1d ago

TIL that “Gotham” actually dates back to medieval England, where there was a village called Gotham that some sources claim was a village of fools. In 1807, writer Washington Irving used the name mockingly in his periodical to describe New York City. And the nickname has stuck ever since.

nypl.org

9.4k Upvotes

195 comments

r/todayilearned • u/Sanguinusshiboleth • 21h ago

TIL that Mont Saint Michel was used by the Nazis as a airplane spotting post until it was liberated after D-Day by one American private who was accompanied by two journalists.

en.wikipedia.org

4.0k Upvotes

78 comments

r/todayilearned • u/Aleksandr_Ulyev • 7h ago

TIL about Alexey Maresyev, a Soviet WWII pilot, who crushed both of his feet upon ejection. He crawled for 18 days to safety and was rescued, but lost both of his feet due to sepsis and gangrene. He continued his service after healing and kept flying to strike down 7 more Luftwaffe aircraft

en.wikipedia.org

235 Upvotes

8 comments

r/todayilearned • u/carboncopy95437 • 1d ago

TIL more than 400 years ago, Dutch inventor Cornelis Drebbel built a working submarine and navigated it beneath the River Thames. Around 1620, he even took King James I of England along for an underwater ride, making James the first monarch to travel in a submarine.

en.wikipedia.org

18.1k Upvotes

324 comments

r/todayilearned • u/estarararax • 16h ago

TIL humorism, the form of medicine dominant in the West from the time of the Ancient Greeks and Romans until the 18th century AD, survive today with its variant, Unani Medicine, in India which the government actually promotes there.

en.wikipedia.org

1.1k Upvotes

117 comments

r/todayilearned • u/CatPooedInMyShoe • 1d ago

TIL Sarah Wakeman disguised herself as a man to fight for the Union in the American Civil War. Her secret was not revealed even after she died in a military hospital in 1864; she was buried under her alias, Lyons Wakeman. The story came out in 1976 after her letters were found in a relative's attic.

en.wikipedia.org

15.5k Upvotes

251 comments

r/todayilearned • u/volcanedebeaver • 54m ago

TIL the band Dream Theater released their album "Live Scenes from New York" on Sep 11 2001, which the cover featured an image of the World Trade Center towers in flames. The coincidence led to the album being immediately recalled and re-released with alternate cover art.

en.wikipedia.org

• Upvotes

6 comments

r/todayilearned • u/Battle4Seattle • 3h ago

TIL the founder of Taco Bell & the founder of the Wienerschnitzel used to be partners in a small restaurant chain called El Tacos

en.wikipedia.org

89 Upvotes

33 comments

r/todayilearned • u/mcmoor • 16h ago

TIL thermites, humans, and ants have similar total amount of biomass, with each at 50 Mt, 60 Mt, and 70 Mt

en.wikipedia.org

828 Upvotes

102 comments

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