f sulphur, which might have choked
us had we not closed the scuttles--while over all great dragons and
other bat-like animals were flitting through the dusky atmosphere like
demons in a nightmare.

Little by little we gained upon our quarry, but being afraid to run him
too close for fear that he might drop his victim, we kept at a safe
distance behind him, yet within rifle range, and near enough to make a
prompt attack when he should settle on the ground.

At length we reached the other side of the valley, and found to our
intense satisfaction that the monster was making for a rocky ledge on
the shoulder of an extinct volcano, where we could see the yawning mouth
of what appeared an immense cavern.

"That is probably his den," said Gazen, who was now as collected as I
have ever seen him. Nevertheless all his faculties were on the stretch.
His keen grey eye was everywhere, and his active mind was calculating
every chance. I felt then as I had often felt before that in action as
well as in thought the professor was a man of no common mark.

The event showed that his surmise was correct, for soon after he had
spoken the dragon uttered a startling cry--a kind of squawk like that of
a drake, but much louder, hoarser, shriller--and alighted on the ground.

"There is not a moment to lose," said Gazen. "We must attack him before
he enters the cave."

Certainly the darkness inside the cavern would give the beast a great
advantage, and although we might succeed in killing him, we could
scarcely hope to find Miss Carmichael alive. Was she alive now? I had my
doubts, but I kept them to myself. Since she had been carried away she
had not given the smallest sign of life, not even when the dragon
settled. Perhaps, however, she had merely lost her senses through
fright, and was still in a dead faint.

We might have fought the creature from the air, but we had decided to
assail him on the solid ground, because we should thus be able to
scatter and take him in the flank, if not in the rear.

While Carmichael landed his car the astronomer and I kept a sharp watch
on the beast, all ready to fire at the first movement which seemed to
threaten the safety of the young girl, who was lying motionless at the
bottom of a slope or talus which led up to the mouth of the cavern.
Freed from his burden the dragon now stood erect, and a more awful
monster it would be difficult to conceive. He must have been at least
forty feet in stature, yet