PART 1
The Archimedes screw is a simple mechanical device invented my Archimedes in the 3rd century. The device, often used to direct water into an irrigation channel, was composed of a wooden beam, several feet long, around which a spiral screw thread was built of layers of flexible, pitch-covered wood strips. Over this thread were fastened tight-fitting narrow planks running the length of the beam and giving it the appearance of a tube. By placing the lower end in water and revolving the screw, water is raised to the top. …
