think of an oreo cookie!

Yes, I think that's it - the current travels through the metal of the pot, and then energizes the water - that's a good way to think of it. This is what I did - I boiled about a gallon of water in one of those oval enamel roasting pans, and cooled it down. I got 2 thin strips of aluminum, and just placed the edge of each one against the pos and neg ends of a D battery, holding the whole thing in one hand, so that the ends of the aluminum strips hung down. Then I lowered the whole thing so that the strips were lower than the top of the pot, but not touching the water. With my free hand, I took both of the strips, with the pot in between them (like they were the chocolate wafers and the pot was the creme filling in an oreo cookie) and pressed them towards each other, against the pot for about 5 seconds. They would have been touching, except, of course, there was a pot in between them. When I took them away and felt them, they were warm, even though the pot was cold. I know the pos strip has to be on one side and the neg on another side of the pot but I forget already which was which - it's in the directions.

It did seem very awkward, I know what you mean. As soon as you do it for yourself, you're going to go AHA! Now it all makes sense ;)