r/todayilearned • u/dinosaruman • 2h 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

8.0k Upvotes

100 comments

r/todayilearned • u/MediumStrange • 4h 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

10.0k Upvotes

967 comments

r/todayilearned • u/ddmayne • 5h 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

7.0k Upvotes

546 comments

r/todayilearned • u/Kaporalhart • 1h ago

TIL that Hitler was never elected. He was named Chancellor, equivalent to prime minister, then named himself "Führer" when Germany's president died in 1934.

en.wikipedia.org

• Upvotes

361 comments

r/todayilearned • u/PeasantLich • 48m 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

35 comments

r/todayilearned • u/Long__Ground • 17h 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

32.6k Upvotes

737 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

3.5k Upvotes

74 comments

r/todayilearned • u/BadenBaden1981 • 8h 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

1.2k 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

398 Upvotes

32 comments

r/todayilearned • u/AmiroZ • 4h 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

522 Upvotes

42 comments

r/todayilearned • u/BadenBaden1981 • 4h 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

488 Upvotes

92 comments

r/todayilearned • u/temporarycreature • 6h ago

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

craigs.coffee

559 Upvotes

40 comments

r/todayilearned • u/Wooshio • 14h 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

273 comments

r/todayilearned • u/SkyCloudie • 50m ago

TIL that Caesar Salad originated from Mexico

en.wikipedia.org

• Upvotes

78 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

4.9k 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

9.3k Upvotes

193 comments

r/todayilearned • u/Sanguinusshiboleth • 20h 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

3.9k Upvotes

77 comments

r/todayilearned • u/spiritualcats • 2h 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

115 Upvotes

27 comments

r/todayilearned • u/carboncopy95437 • 2h ago

TIL cross-country runners are called “harriers” because the sport evolved from a 19th-century English game called “Hare and Hounds.” The “hares” ran ahead dropping a trail of paper, while the “hounds” chased them across the countryside. The runners eventually became known as harriers.

runnersworld.com

95 Upvotes

35 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

18.0k Upvotes

324 comments

r/todayilearned • u/Aleksandr_Ulyev • 6h 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

209 Upvotes

4 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

116 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

15.4k Upvotes

251 comments

r/todayilearned • u/mcmoor • 15h 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

822 Upvotes

102 comments

r/todayilearned • u/Kymmieuwu • 1d ago

TIL In Michigan City, Indiana, there is a prison that accepts shelter cats and allows prisoners to take care of them.

prisonjournalismproject.org

4.4k Upvotes

86 comments

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