› added 4 years ago

234

TIL that a manhole cover is round because if it is square or oval, it can fall into the sewer!

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xV6w0 TIL James O’Keefe impersonated a wealthy donor, but forgot to hang up the phone and accidentally recorded a long message explaining the details of the operation
LZBQ TIL all military working dogs are ranked a level higher than their handlers. This is a traditional started to prevent handlers from mistreating the dog.
gM1Gb TIL the Japanese squadron that bombed Pearl harbour was detected by a prototype Hawaiian Radar before the air raid but no alert was sent out, as nobody believed the inexperienced radar operators.
b9kg0 TIL at high enough speeds an aircraft can use it's own shockwaves to generate a considerable amount of additional lift. This phenomenon is called compression lift and has only been demonstrated to two aircraft models.
xMwo TIL that Islamic schools, “Maddrassas,” funded largely by Saudi Arabia, provide the only viable means for most Pakistani boys to get an education, and in many regions outnumber the state run schools.