"Oz" wrote in message
...
Gordon Couger writes

It's an air lift pump.

Oh, right.

Also well described scientifically, although best used for difficult
liquids as it's horribly inefficient.

--
Oz
This post is worth absolutely nothing and is probably fallacious.
Note: soon (maybe already) only posts via despammed.com will be
accepted.


Both the air lift pump and hammer pump lift a proportion of water from a
body of water that has a head over its destination without input of
energy from the outside by using some of the energy in the head. You
say both types are very inefficient.

If you get the water lifted that you require why does it matter if the
pump harvests only a small part of the energy in the head as the
inefficiency isn't costing you input energy?

What type of pump that needs no external energy source is efficient by
your standards?

David