It starts in the cave.

None of us ever followed it, because it's so dark and wet.

A fellow found an old musket stock there once." "What do you say ?" he called; "there's no time to lose, that's sure.
Shall I try it?
It would take an hour to flood this pesky old hole, even if I could stop up the passage." Then all of a sudden I knew why he had told me to be ready with the paddle.

It was so I could open a little trench through the muddy land and start the water flowing into the pit.

That way he'd get to the top with Skinny.
"But you can't stop up the passageway," I said.