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
SS Archimedes a six-bladed "windmill" propeller designed by himself. Brunel's design was to prove a costly failure for the company. Smith and his fellow investors had originally hoped to sell "Archimedes" to the Royal Navy, but when this did not eventuate, the Ship Propeller Company sold the vessel into commercial service. The company, which is estimated to have lost a total of about £50,000 on the "Archimedes" venture, was subsequently wound up. The later career of "Archimedes" is sketchy. The ship ran aground at Beachy Head in 1840. In 1845, she disappeared from Lloyd's Register, but appeared again in 1847 following an