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) near the rim. Scattered wisps of bright ray material lie across the floor, most likely deposited by the impact that created Autolycus. To the south of Archimedes extends the Montes Archimedes, a mountainous region. On the southeastern rim is the Palus Putredinis, a lava-flooded plain containing a system of rilles named the Rimae Archimedes, which extends over 150 kilometers. North-northwest of Archimedes stand the Montes Spitzbergen, a string of peaks in the Mare Imbrium. East of Archimedes is the crater Autolycus. Northeast of Archimedes is the prominent crater Aristillus. The lava plain between Archimedes, Aristillus, and Autolycus forms the Sinus