Archimedes screw

Archimedes invented a modification of the screw, applied to pump water. Conceptually, think of a tube wrapped around a shaft. Let the shaft be tilted somewhat from the vertical. As the bottom end of the tube turns through water, it will scoop up a bit of water. This puddle of water will slide up in the spiral tube as the shaft is turned, until finally it falls out of the top of the spiral tube.\n