"We are caught," muttered the scientist. "There is no other door."

Gray was aware of this. The only openings in the chamber where they stood were the door and the aperture in the floor. The pad-pad came nearer, but more slowly. He was reasonably sure that they had not been seen. It was abominably bad luck that some one should visit the gallery just then.

"We left the temple door open," Delabar whispered, staring at the dark stairs behind them. "One of the priests observed it and came——"

"Steady," Gray cautioned him. He drew the trembling Syrian back into the shadows at one side of the door. Here they were in semi-obscurity. Stepping quietly to arm's reach of the head of the stairs, Gray waited.

He heard the steps approach, then become silent as if the intruder was looking into the room.

A moment passed while Gray silently cursed the heavy breathing of Delabar who seemed possessed by uncontrollable excitement. Then a shaven head appeared in the doorway, followed by a naked shoulder. A pair of slant, evil eyes flickered around the gallery, failing to notice the two white men in the shadow.

Gray's hand went out and closed on the throat of the priest. His grip tightened, choking off a smothered gasp. The man fell heavily to his knees.

The floor echoed dully at the impact. Gray realized that it must have been heard by those in the temple below. Snatching up the frail priest by throat and leg, he lifted him easily and started down the stairs headlong.

"This way, Professor," he called. "Better hurry."

Concealment being useless now, they plunged down the steps. By the time the lower floor was reached, Gray's grip had stilled the struggles of the man—whom he recognized as the ascetic.