"Take some of your men with you and reconnoiter," ordered Zveri.

Abu Batn summoned a half dozen of his black men, who advanced with evident reluctance.

Gathering the skirt of his thôb about him, the sheykh entered the crevice, and at the same instant a piercing screech broke from the interior of the ruined city—a long drawn, high pitched shriek that ended in a series of low moans. The Bedaùwy halted. The blacks froze in terrified rigidity.

"Go on!" yelled Zveri. "A scream can't kill you!"

"Wullah!" exclaimed one of the Aarabs; "but jân can."

"Get out of there, then!" cried Zveri angrily. "If you damned cowards are afraid to go, I'll go in myself."

There was no argument. The Aarabs stepped aside. And then a little monkey, screaming with terror, appeared upon the top of the wall from the inside of the city. His sudden and noisy appearance brought every eye to bear upon him. They saw him turn an affrighted glance backward over his shoulder and then, with a loud scream, leap far out to the ground below. It scarcely seemed that he could survive the jump, yet it barely sufficed to interrupt his flight, for he was on his way again in an instant as, with prodigious leaps and bounds, he fled screaming out across the barren plains.

It was the last straw. The shaken nerves of the superstitious blacks gave way to the sudden strain; and almost with one accord they turned and fled the dismal city, while close upon their heels were Abu Batn and his desert warriors in swift and undignified retreat.

Peter Zveri and his three white companions, finding themselves suddenly deserted, looked at one another questioningly. "The dirty cowards!" exclaimed Zveri angrily. "You go back, Mike, and see if you can rally them. We are going on in, now that we are here."

Michael Dorsky, only too glad of any assignment that took him farther away from Opar, started at a brisk run after the fleeing warriors, while Zveri turned once more into the fissure with Miguel Romero and Paul Ivitch at his heels.