I was rereading Huckleberry Finn (1884) last weekend, and came across:

"There warn't anybody at the church, except maybe a hog or two, for there
warn't any lock on the door, and hogs like a puncheon floor in summer-time
because it's cool.  If you notice, most folks don't go to church only when
they've got to; but a hog is different."

- and then somebody at IPTW said something about a puncheon floor and I asked
a couple of people what it was.  Apparently not everybody calls it that, so
having asked, I thought I'd share what turned up.

the Collegiate Dictionary def 2b "a split log or heavy slab with the face
smoothed"

the New Shorter OED def 2a "a heavy piece of rough timber or a split trunk,
used for flooring and rough building"

Would the coolness of the floor come from air pockets around split logs, or
just from the  ground underneath?

Kathy Follett