› added 6 years ago

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TIL why coins have ridges on the sides... Criminals in the 1700s saw they could make a good profit by filing shavings from the sides of gold and silver coins. Today’s coins contain no precious metals but, you’ll still find those ridges to make them distinguishable for visually impaired people.

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E15mV TIL that SR-71 Blackbird ,the fastest manned aircraft ever doesn't have a fuel tank ,the fuel is stored in the body of the aircraft itself (for savin weight) ,the body has seams and gaps so the fuel leaks while it isn't flying. The engineers expect the pressure at higher altitudes to close the gaps.
4ogR TIL that in 2006, Florida passed Amendment 3 which states that any proposed amendment to or revision of the State Constitution requires at least 60% of votes. It passed with 57%.
OGM9a TIL that Ben S. Cauley, Jr. was the sole survivor of the plane crash that killed singer Otis Redding & 6 other people in 1967. Cauley took off his seat belt shortly before the crash. He managed to cling to a seat cushion for 20 minutes, until a rescue boat pulled him from the freezing lake waters.
Z8ppv TIL of a woman who tricked her girlfriend into sex by pretending to be a man. She was jailed for 6.5 years for using a fake penis on her partner.
R7WJa TIL the reef stonefish (Synanceia verrucosa) is not only a master predator but one of the most venomous fish in the world, even lethal to humans. Its appearance is that of a crusty rock affording the fish uncanny camouflage. Each of its 13 dorsal spines has two venom sacs containing 3 deadly toxins.