n the wall and found
themselves in a long gloomy corridor. "Quick," Reubens whispered.

They darted down the passageway. Talbot had only time to see that the
gleaming sides of the corridor were beveled and etched with strange
designs, before they came to its end and where a curious device like a
huge five-pointed star was revolving noiselessly, half sunk in a great
hole in the floor. Without hesitation the Professor stepped onto one of
the flat-tipped star-points as it came level with where they stood and
Talbot did the same. Up, turned the star-point, to a dizzy height, and
over, but the tip swung on ball-bearings, maintaining its passengers in
a perpendicular position, and from its highest point of elevation
descended to another floor far below, where they disembarked.

The huge revolving star-wheel was nothing but an ingenious movable
staircase. But the Professor gave Talbot no time to marvel, nor did the
latter try to linger. The corridor below was wider, more richly beveled
and carved, and the statue of an heroic bird stood perched in the
center of it. The lighting was soft and mellow, but Talbot could
perceive no windows or globes. Suddenly from an open doorway hopped a
bird. There was no chance to avoid it. Its wings were spread and from
its parted bill came a harsh cry, "Toc-toc, toc-toc!"

Knife in one hand, the Professor hurled himself forward and caught the
bird in the grip of the other. Instantly from the doorway sprang a
monstrous mechanism on stilts, flexible tentacles of metal reaching out
and wrapping themselves around the Professor. Talbot leaped to the
Professor's assistance. The mechanism fought like a live thing. In vain
he strove to wrench the tentacles free of the Professor. One of them
lashed out and took him by the thighs in a crushing grasp. But the
Professor had the bird by the throat. Both of his hands were free.
Back, he forced its head, back. The mechanism seemed to falter in the
attack, as if bewildered. Across the exposed throat the Professor drew
the gleaming blade. Flesh, tendons and arteries gave, blood spurted,
and in the same moment the tentacles fell away from Talbot and the
Professor and withdrew with a dull clang. The Professor released the
bird and it dropped to the floor.

"It is the birds' mentality that directs those mechanisms," said the
Professor, pointing to the now harmless machine.

Apparently the brief but terrific battle had passed unnoticed, no alarm
being given.