For several hours they searched eagerly for some means of getting out of the underground city. They went to the farthest limits of it, and found it to be several miles in diameter, but eventually they came to solid walls of stone which reached from roof to ceiling, and there was no way out.
They found that the underground city was exactly like an overturned bowl, or an Esquimo ice hut, hollow within, and with a tunnel leading to it—but all below the surface of the earth. The city had been hollowed out of solid rock, and there was but one way in or out, and that was closed by the seamless stone.
"There's no use hunting any longer," declared Tom, when, weary and footsore, they had completed a circuit of the outer circumference of the city, "the rock passage is our only hope."
"And that's no hope at all!" declared Ned.
"Yes, we must try to raise that stone slab, or—break it!" cried Tom desperately. "Come on."
"Wait a bit," advised Mr. Damon. "Bless my dinner plate! but I'm hungry. We brought some food along, and my advice to you is to eat and keep up our strength. We'll need it."
"By golly gracious, that's so!" declared Eradicate. "I'll git de eatin's."
Fortunately there was a goodly supply, and,
