Cser Laszlo wrote:

>> Telephone used an earth ground for the return current.
> How could this happen?  Was one of the wires accidentally tied to the
> earth ground?

  This is a *very old* story.  You have to know that it was a rural
situation where "party lines" were used.  A party line has two (or
more!) subscribers on the one line!  One subscriber has bell connected
between one wire and ground, the other between the other wire and
ground, so there are in effect, two different bells.

  Party lines for more subscribers used "selective ring" (now available
for home businesses etc. - a resurgence!) where each was to respond to a
different ring sequence.

  "Duplex" circuits allowed a relay box at each of the 2 subscribers on
a party line to have privacy.  Not only did the bell return to ground,
but so did both line circuits in order to make the connection, after
which they looped normally.

  We had one of these when I was little, this was in Sydney, not rural.
You pressed a button on top of the phone to seize the line.  Boy, I *am*
old!

> In the normal dry situation why did the circuit complete via the dog?
> Why was the resistance between the dog's paw and the soil smaller than
> between the stake and the soil?

  Because the stake was next to the house, shaded from the rain!  (What
rain?)

> Please answer in a private mail.

  You're kidding!

  Sean has already been reminded to think in 3D resistance instead of
1D, so that's well covered.
--
  Cheers,
        Paul B.