Originally Posted by marinera
Ok it all boils down to the water creating a better vacuum than air, I think. But then why people report less fluid build-up with water pumping? This seems to show the adverse of what we are assuming.
I’ve been thinking about that too. Why should that be? One thought I’ve had has to do that with water pumping, you have water OUTSIDE the penis (in the cylinder) and water INSIDE the penis (in the tissues and the blood vessels).
Water is going to be relatively incompressible (or nonexpandable) wherever it is, whether it is inside or outside the penis.
With water pumping, there is water outside the penis, water INside the penis, and a barrier of tissues in between. The tissues act as a barrier to complete equalization of forces inside and outside the penis, but as the forces equalize (through expansion of the penile tissues), there is no particular reason for the water to ‘want to be’ either inside or outside the penis. It’s got no reason to move. And what’s outside the penis is noncompressible water, so if water did want to try to escape into the intracellular spaces, the expansion would have to take place by compressing the water all around the penis, and it can’t do that.
I’m thinking that water outside the penis may hold back water inside the penis leaking from the blood vessels and cells into the intracellular spaces. This would also explain why condom pumping works, by the way. It’s encouraging the TISSUES to expand more, rather than allowing intracellular leakage.
Originally Posted by marinera
I guess the weight of the sand would push out air. Or it could be done with salt water; if one wanted to try a very high level of force (what would not really be a good idea for the vast majority of people).
There is a LOT of air between the grains of sand. Take a glass, fill it up with sand, then take a calibrated amount of water (say, from a measuring cup) and start pouring it into the glass of sand. See just how much more space you are filling up between the grains of sand.
Originally Posted by Tossed Salad
I think it might have to do with sweating.
When I air pump my tube fills with moisture (condensation) as water is being pulled out of the skin. Having water in the tube prevents this from happening.
Negative. Your dick sweats (or loses water through the cell walls into the cylinder) either way, is my guess. You just don’t see it when you’re water pumping, because it’s lost into the surrounding water. Think about it - do you think you don’t sweat when you’re in a hot tub? You do; it’s just that you’re sweating into the water around you.
(Now try not to think about all the other people who have been in the hot tub sweating into the hot tub water before you were there, the next time you get in a hot tub.)
Originally Posted by capernicus1
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I cant help thinking also that the use of a liquid in the tube presents other possibilities ,
for instance adding substances to water to counter discolouration, increase blood flow or soften tissue, or using fluids other than water which may be denser
or retain heat better ?
For some reason i keep thinking about how salt water conducts electricity but i think i may be losing my grip on reality !
I’ve also been thinking about how tap water is hypo-osmular - it’s less salty and less ‘dense’ than your plasma and body fluids. That would encourage your ‘saltier’ penis and tissues to take in fluids as it tries to equalize with the surrounding hypotonic water.
One strategy to reduce fluid buildup in the penis might just be to add a little salt to the water you’re pumping in, so that it is closer to the salinity of your blood, lymph and body fluids. If it was REALLY salty, it would tend to draw water OUT OF your penis, so you don’t want too much of that; not to mention, you don’t want to wind up with a brined or pickled penis.