Nicky gripped his arm.

From the lower levels came a muffled report! Bill had fired into the air as a body of soldiers came, in their light cotton quilted armor, carrying bows and arrows and short spears; they had to stop in face of his “magic stick” that spat out fire and sudden death.

“We must go to Bill!” whispered Cliff. “We can’t get out through the square! If we can get through the passages we may be able to hide.” The others agreed. With the Inca, Huamachaco and Pizzara in hot pursuit, but unarmed, they almost leaped down the curving steps.

Bill stood at their foot, his back to them, his weapon leveled. Before him half a dozen soldiers hesitated.

“We’re here!” cried Cliff. Then he saw Tom, just around the edge of the wall, tense and alert, his own light, and in this emergency almost useless weapon held ready.

If only they had known Tom was there, two minutes sooner!

Before they could make any concerted plan Pizzara, with his quick cunning serving him, caught old, weakened Mr. Gray by an arm: he saw that Bill could possibly daunt the soldiers; with merciless cruelty he dragged the old scholar past Bill before the others quite knew what he meant to do. Immediately he swung Mr. Gray, who was not strong enough to resist the surprise attack: Pizzara swung him so that his own body was shielded.

Bill saw, too late, the ruse. His weapon was useless: in that narrow place he could not fire without endangering the old student of ancient civilizations.

“Down, Father!” Cliff cried. “Drop down!”

The old man had recovered his balance. With all his small strength he tried to fling off Pizzara’s grip, to lower his body. At the same instant the high priest and the Inca caught hold of Mr. Whitley and Bill. Cliff and Nicky in turn grasped them. Tom broke past Bill and caught a tackle around Pizzara’s legs. His balance thus disturbed the Spaniard lost his grip on Mr. Gray.