So the Flatheads cunningly made their wall invisible, believing that everyone who saw the entrance to the mountain would walk straight toward it, as we did, and find it impossible to go any farther.

I suppose the wall is really high and thick, and can't be broken through, so those who find it in their way are obliged to go away again." "Well," said Dorothy, "if there's a way around the wall, where is it ?" "We must find it," returned Ozma, and began feeling her way along the wall.

Dorothy followed and began to get discouraged when Ozma had walked nearly a quarter of a mile away from the entrance.

But now the invisible wall curved in toward the side of the mountain and suddenly ended, leaving just space enough between the wall and the mountain for an ordinary person to pass through.
The girls went in, single file, and Ozma explained that they were now behind the barrier and could go back to the entrance.

They met no further obstructions.
"Most people, Ozma, wouldn't have figured this thing out the way you did," remarked Dorothy.