Please Please Help Me Understand This ...

Hi All,

Great forum, thank you to all who made it possible,

I conducted a simple experiment but I not able to understand/explain the results,

In large bowl full of material composed mostly of: FINE SAND + WATER + SALT(natural unrefined) probably
in equal parts which made it look like a paste (see pic)
I placed two electrodes: (+) GRAPHITE ROD and (-) MAGNESIUM at various distance (D) from each other,
the multimeter reading across the electrodes was showing stable 1.5V no matter the distance (D)!!??

The next experiment - the same setup - I only covered up the electrodes with plastic wrap as in fully isolating each electrodes from the electrolyte (the material), I was surprised to get nearly enough the same reading (about 1.42V)!!??

Can some please explain - preferably with some basic formulas what is happening here:

1. what do I have here: a BATTERY? a CAPACITOR? a GALVANIC BATTERY?
2. why is the distance between the electrodes not making any differences?
3. If this is a BATTERY of some sort - is there a theoretical way to estimate the energy stored therein?

Many thanks in advance.