I thought I would add a link ...

I thought I would add a link to the basic concept. With an absolute vacuum at the top, the pressure head with more mass is the one that should act on the other pressure head. And with a height of less than 9.8 meters, the pressure at the bottom of the pressure head would be less than atmospheric pressure and could not discharge as a result. And as I mentioned, if this is found to work, I'm sure there are people who could benefit from it as water could be pumped and possibly even desalinated as a mechanical pump with leverage could generate sufficient pressure. Might be a bit old fashioned but when potable water is in short supply, maybe something like this is needed. http://i979.photobucket.com/albums/ae278/bessler_supporter/General%20Engineering/SelfPrimingPump_zpsa39ab079.jpg