"Benj" wrote in message
ups.com...

Andrew K Fletcher wrote:
Basic theory behind the experiment which caused water to flow 24 metres up
a
cliff in Brixham, Devon.
http://www3.sympatico.ca/slavek.krep...cienceRevw.htm
[Hemet]
Hi Andrew :-)
You have the honor of being a true scientist and experimentalist. Yet
you have to answer for some big questions.

I agree with Hemet that the theory is not correct.
One other thing that it does not explain is how plants have CONTROL
over water pumping. Wilting and restoration can be stimulated
electrically!

To disagree with this theory is to suggest a mechanism for evaporation that
does not have any effect on the density of residual fluids inside the tree.
Please elaborate as I find this impossible to understand. If we can agree on
density changes due to evaporationin transpiring leaves then the rest of the
theory is correct also.

Andrew

Hemet also asked me to answer Strasburger's results, Which I have done, and
will add after you have addressed this question at hand.

I think there are a few hints to this long-time question, but I have
never done enough work to generate a bone fide theory about it.

Basically I believe that somehow water pumping in plants is an
electrical phenomena. (See some of the great work by Prof Bose in his
old book) My idea is that there is a REQUIREMENT that sap contain
dissolved chemicals because pure distilled water would not be
conductive enough nor polar enough to be electrically pumped.

If you examine Xylems (tubes through which sap rises) you find very
interesting structures. There are cell membranes that exist between a
spiral thread of cellulose (insulator) creating a spiral membrane
rising up the tube. I suggest (but have not established) that an
action potential may travel this membrane such that it creates a
pumping action for the fluid in the tube. This action would be
similar to the action found in nerves in animals but has a pumping
function in plants. Such would explain Bose's electrical reversal of
wilting. Also it is already known that tall plants have valves in the
xylems which usually do not require sap to be pumped more than a few
feet.

Just some "new theory" food for thought!

Benj