Someone posted this earlier, it has the instructions.  I think you want the moisture to enter, but no contact with the outside soil.

http://www.overunity.com/index.php?action=dlattach;topic=3500.0;attach=15689

I think they do paint the outside of the pipe giving the outside soil no contact with the inside, with plastic on the bottom.  In my cell I covered only the bottom, so I will see at least if there is an increase in voltage.  I found that amperage is easily achieved with more copper and zinc, although the hard part is multiplying the voltage to allow for more power to flow through.  I'm trying something like a voltaic pile to try and increase voltage.

@ Freezer,

You wanted to know where you could find a photo of the Stubblefield earth batteries. I could not find the picture in the thread, so I'm posting it again.

Hans von Lieven

Looks like he uses a ton of cells.  I think its something like 50 cells in that box and they are in sacks?  So he just uses dirt as electrolyte?  Maybe he has a connection to earth, then goes through the cell bank, and then back to ground?

Has anyone read the book on Stubblefield by Bob Lochte? Is it worth getting?

@ Freezer,

I think this is just a box full of batteries he put there for the photograph. I don't think it is part of a working circuit.

Hans von Lieven