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101

TIL why blueprints are blue. They have a chemical called Ferric Ferrocyanide (which is light sensitive) and was used on the paper to make copies of designs and drafts, ultimately leading to that iconic blue color.

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yV8nl TIL that aqueducts are water channels that use gravity to move water from a source to a destination. An ancient Roman aqueduct used only a 51 foot height difference to push water down a 31-mile-long path, resulting in as little as a 1-inch drop to push water 1,500 feet.
aW8Z TIL Tennis star Novak Djokovic bought the entire supply of Pule cheese, a rare donkey cheese that is only produced in his home country of Serbia. This is also considered the most expensive cheese in the world.
5Y96R TIL: That 'Aryan' and 'Iran' and 'Iranian' all come from the same word, and some of the 'purest' of Aryans are Kashmiri, Romani Gypsies and Punjabi.
rrO0 TIL in 458BC Roman farmer Lucius Cincinnatus was named absolute dictator of Rome during a crises. After achieving victory he resigned and returned power to senate. His resignation of absolute authority is often cited as an example of outstanding leadership, serving the greater good and civic virtue.
oEdA TIL that English has 2 distinct P sounds: aspirated and unaspirated. If one holds one’s hand in front of one’s mouth and says “Pin” & “sPin”, one will feel a burst of air with “Pin” but not “sPin.” In languages like Korean, these are totally different sounds/letters that can change a word’s meaning