And then I knew. Complete comprehension flashed through my brain on the instant. I sprang to my feet, and my thought must have shown on my face, for Harry looked at me in surprise, demanding:
"What is it? What is it, Paul?"
And I answered calmly:
"We're caught, Hal. Like rats in a trap. Oh, the black devils! Listen! We have no time to lose. Bend over and touch the palm of your hand to the ground."
He did so, plainly puzzled. Then he drew his hand hastily away, exclaiming: "It's hot!"
"Yes." I spoke quickly. "Our boots kept us from feeling it before, and the stone doesn't throw out enough heat to feel it in the air. They've built a fire under us in the column. The stone is thick and heats slowly."
"But what—that means—"
"It means one of two things. In a few minutes this floor will be baking hot. Then we either fry on their stone griddle or drown in the lake. You see the distance below—only a man crazed by suffering or one incredibly brave would take that leap. This is their little entertainment—they expect us to dance for them."
"But the lake! If we could take it clean—"
I saw that the lake was our only chance, if there could be said to be any in so desperate a situation. To be sure, there seemed to be no possibility of escaping, even if we took the water without injury. On every side its bank was lined with the watching Incas, and the bank itself was so steep that to ascend it would have required wings.