en kingdoms."

"But," reminded the other, "you had no choice, old lad. Remember, you
mixed in to save me."

From across the courtyard rang a loud, penetrating shriek of fear that
made the two aviators spring to their feet and rush to the bars.
Peering across the court, they discovered three naked men shrieking
and clinging frantically to the bars of an exactly similar cell.

"What's wrong with them?" demanded Alden as the agonized screams rang
louder still.

"I don't know," was Alden's breathless reply. "But what's that noise?"

A curious metallic clanking sound filled the poisoned air, and for a
moment Nelson remained utterly puzzled. Then, as the noise grew
louder, the allosauri commenced to betray a strange restlessness. They
ceased basking and feeding, and their hideous heads commenced to dart
quickly this way and that.

* * * * *

While the terrific shrieks of the wretches across the court rang to
the copper-hued sky, the two Americans remained in doubt; then all at
once the chill of death gripped their hearts, as they saw the bars of
that cell directly opposite slowly but surely rising! Uttering
heart-rending cries, the doomed prisoners clung frantically to stay
the vanishing barrier separating them from those appalling man-eaters.
But, disdainful of their pitiful efforts, the bronze bars rose
relentlessly with metallic rattlings and janglings from some unseen
mechanism.

Rooted to the floor, both Americans watched the distant grille vanish
into the upper stone-work and heard the ghastly hissing as the
allosauri herd commenced to move forward. Sick and shaken, Nelson
beheld one of the doomed men cling in desperation to the bars; he was
lifted clear of the floor and borne towards the ceiling, meanwhile
venting his terror with such screams as could otherwise have risen
only from an inquisitor's torture chamber.

The tragedy was swiftly completed. Half a dozen of the nearest
allosauri, taller than any giraffes, suddenly sprang forward, their
long, naked tails rising as their gait increased. Snarling horribly,
the vast slate-colored beasts plunged into the cell, terminating
shrieks of mortal terror. Backs broader than bus tops squirmed and
tugged, then one of the loathsome monsters reappeared carrying in its
dripping jaws a mangled, yet struggling victim much as a cat carries a
mouse. In a trice the other allosauri came rushing eagerly up, seeking
to snatch the prey from the