Over the ages, a lot of human activity has been concerned about getting water from where we find it to where we want it. If you want to move water to a lower elevation, there’s no problem. But if you want to move water up, you need a pump. The ancients used what we call Archimedes’ screw to raise water. But a Wirtz pump as [Steve Mould] shows in the video below, is another kind of spiral pump that is also very old and uses the same basic principle as the screw pump.
In a way, the Wirtz is just an Archimedes’ screw in cross-section. Part of what makes it work, however, is air-locking. [Steve] made a small model but found it didn’t work exactly as he expected. Of course, investigating that led to some interesting observations.