overhead. This main avenue was not more than eight or ten feet wide.

Every few steps other lofty and still narrower crevices branched from it on either hand — for McDougal’s cave was but a vast labyrinth of crooked aisles that ran into each other and out again and led nowhere. It was said that one might wander days and nights together through its intricate tangle of rifts and chasms, and never find the end of the cave; and that he might go down, and down, and still down, into the earth, and it was just the same — labyrinth under labyrinth, and no end to any of them. No man “knew” the cave. That was an impossible thing. Most of the young men knew a portion of it, and it was not customary to venture much beyond this known portion. Tom Sawyer knew as much of the cave as any one.