Archimedes (287 BCE-212 BCE) was a Greek mathematician, physicist and astronomer. While experimenting, he found that a body when immersed in a liquid loses weight equal to the weight of the liquid it displaces. This was the formation of a hydrostatic principle and is known as Archimedes’ principle. Archimedes is popularly known for this principle. He also invented the Archimedes’ screw to pull water out of the ground. This device is still used around the world.