“Stop!” he shouted. But there was a grumble and murmur from the crowd pressed against the line of soldiers, with their tin-and-copper alloy swords out and ready. There was more danger than merely that of arrest and confinement. There was an ominous threat in the sound of that hoarsely guttural murmur.

Cliff had his arms free; a soldier, seeing that no harm came to those who had seized Chasca, himself advanced. Cliff backed toward the temple steps again, at Mr. Whitley’s swift order.

But Challcuchima had flung off Tom, had, in fact, given him a vicious punch that took Tom’s wind for the instant.

Challcuchima caught at Cliff again. Cliff’s hand shot out as Mr. Whitley leaped off the step and swung the Inca’s older brother aside before he could aid Challcuchima. Cliff’s blow struck true and the younger son went down.

“Get back into the temple!” cried Bill.

There was a sharp, startling bark from his revolver; he fired above the heads of the crowd.

That unusual sound arrested every motion for an instant. Nicky squirmed free from Huamachaco who had risen and grasped him. Cliff started backward but his foot caught on the lowest step. He lost his balance but Nicky caught and steadied him. Bill and Mr. Whitley rushed down to aid Tom, who had dropped, sick and weakened by Challcuchima’s unexpected blow.

Then there came an ominous sound—a laugh of triumph.

The Inca, with several soldiers, had gained the top step and escape into the temple was cut off!

The angry crowd surged forward, pushing the soldiers with them.