Answer:
"Shut in like a tunnel"
"One morning, when we was pretty well down the State of Arkansaw, we
come in sight of a little one-horse town in a big bend; so we tied up
about three-quarters of a mile above it, in the mouth of a crick which
was shut in like a tunnel by the cypress trees, and all of us but Jim
took the canoe and went down there to see if there was any chance in
that place for our show."
"whooping and yelling like an Injun"
"Boggs comes a-tearing along on his horse, whooping and yelling like
an Injun, and singing out: 'Cler the track, thar. I'm on the
waw-path, and the price uv coffins is a-gwyne to raise."