The high walls rising so close together upon either side seemed to shut out the light of day.
The air-ship could not possibly have entered this narrow crack in the mountain wall, just as Harding had said.
“Ugh! This is indeed a most unwholesome place!” said Frank.
“As I told you,” said Harding; “but it was once a gateway through the mountains.”
“Indeed!”
“I believe it. You will notice the peculiar formation of the walls. An earthquake no doubt has brought about this peculiar state of affairs.”
“You may be right,” agreed Frank. “Ah, what wonderful things the world contains, which but few of its people are ever permitted to see.”
“You are right there,” agreed Harding, in a hearty manner.
“But I don’t see how you ever found your way through here.”
“Indeed, I was a long time in these parts before I was able to find it, though I had a plan of the spot, given me by a dying Incas chief. I finally succeeded.”