Browse

2 breaks
AllBiologyComputingEarth & SpaceEconomicsEngineeringFood ScienceHistoryLanguageMathsMindMusic & SoundPhysics
How a stick and a well measured the whole Earth: Eratosthenes Around 240 BC, the librarian Eratosthenes measured the size of the Earth using a well, a stick and a shadow. At noon on the summer solstice the sun shone… History4 min read How computers fake grey using only black and white dots Old Mac screens, cheap printers and some modern games can only show two colours: black and white. Yet they still draw soft shadows and smooth skies. The trick… Computing5 min read