--- In pulserpump@yahoogroups.com,
"peekay" <pksharmakolkata@...> wrote:
> i remember seeing a mention about such a pump being used to ventilate
> a mine on a very very large scale .. using a pulser pump
> that mine has since been abandoned and the humungous device set up
> by the mining company long long ago has also become unused
> but probably still exists ..
> ..peekay

Your are refering to something like the Ragged Chutes Hydraulic Air
Compressor on the Montreal River in Canada.
It is described in some detail at:
<http://www.cobalt.ca/ragged_chutes.htm>

The bubble pump air compressor described in posts 41 & 42 incorporate
some of the ideas of the hydraulic air compressor at Ragged Chutes but
is an entirely different beast supposed to run on diurnal fluctuations
of ambient air temperature. It will never go!

stanhbaker