Archimedes' screw pipe does not need to be perfectly watertight, as long as the amount of water being scooped with each turn is large compared to the amount of water leaking out of each section of the screw per turn. If water from one section leaks into the next lower one, it will be transferred upwards by the next segment of the screw. In some designs, the screw is fused to the casing and they both rotate together, instead of the screw turning within a stationary casing. The screw could be sealed to the casing with pitch resin or other adhesive, or
Archimedes (crater) in what he thought to be a mid-sized crater in the south of the rim of what is now Plato, between that crater (then as "Lacus Panciroli") and Mare Imbrium (then as "Mare Astronomicum"). The stretch of lunar surface between Archimedes and Autolycus was the site of the crash-landing of the Soviet probe Luna 2. This was the first craft to reach the surface of the Moon, landing September 13, 1959. By convention these features are identified on lunar maps by placing the letter on the side of the crater midpoint that is closest to Archimedes. The following craters have