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The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.
Archimedes' achievements in this area include a proof of the law of the lever, [10] the widespread use of the concept of center of gravity, [11] and the enunciation of the law of buoyancy known as Archimedes' principle. [12] In astronomy, he made measurements of the apparent diameter of the Sun and the size of the universe.
The Claw of Archimedes (Ancient Greek: Ἁρπάγη, romanized: harpágē, lit. 'snatcher'; also known as the iron hand ) was an ancient weapon devised by Archimedes to defend the seaward portion of Syracuse 's city wall against amphibious assault .
5. Play-Doh. Who: Kay Zufall, Brian, Joseph McVicker, Bill Rhodenbaugh When: 1956 . How it was created: The gooey toy kids have been playing with for decades began as a household cleaning product ...
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Here are nine of the accidental inventions we use every day. Skip to main content. 24/7 Help. For premium support please call: 800-290-4726 more ways to reach us. Sign in ...
Method of exhaustion: Formalized by Eudoxus of Cnidus in the early 4th century BC, used by Archimedes to calculate the value of pi and the area under a curve. [95] Mathematical proof: The mathematical proof was a product of Greek mathematics, evolving gradually to reach the method still used today in Euclid's Elements around 300 BC. [96]
Following Archimedes's estimate of a myriad (10,000) grains of sand in a poppy seed; 64,000 poppy seeds in a dactyl-sphere; the length of a stadium as 10,000 dactyls; and accepting 19mm as the width of a dactyl, the diameter of Archimedes's typical sand grain would be 18.3 μm, which today we would call a grain of silt. Currently, the smallest ...