The grazing herds moved to one side as I passed through them, the little orthopi evincing the greatest wariness and galloping to safest distances.  All the animals stopped feeding as I approached, and after moving to what they considered a safe distance stood contemplating me with serious eyes and up-cocked ears.  Once one of the old bull antelopes of the striped species lowered his head and bellowed angrily—­even taking a few steps in my direction, so that I thought he meant to charge; but after I had passed, he resumed feeding as though nothing had disturbed him.

Near the lower end of the valley I passed a number of tapirs, and across the river saw a great sadok, the enormous double-horned progenitor of the modern rhinoceros.  At the valley’s end the cliffs upon the left ran out into the sea, so that to pass around them as I desired to do it was necessary to scale them in search of a ledge along which I might continue my journey.  Some fifty feet from the base I came upon a projection which formed a natural path along the face of the cliff, and this I followed out over the sea toward the cliff’s end.

Here the ledge inclined rapidly upward toward the top of the cliffs—­the stratum which formed it evidently having been forced up at this steep angle when the mountains behind it were born.  As I climbed carefully up the ascent my attention suddenly was attracted aloft by the sound of strange hissing, and what resembled the flapping of wings.

And at the first glance there broke upon my horrified vision the most frightful thing I had seen even within Pellucidar.  It was a giant dragon such as is pictured in the legends and fairy tales of earth folk.  Its huge body must have measured forty feet in length, while the batlike wings that supported it in midair had a spread of fully thirty.  Its gaping jaws were armed with long, sharp teeth, and its claw equipped with horrible talons.

The hissing noise which had first attracted my attention was issuing from its throat, and seemed to be directed at something beyond and below me which I could not see.  The ledge upon which I stood terminated abruptly a few paces farther on, and as I reached the end I saw the cause of the reptile’s agitation.

Some time in past ages an earthquake had produced a fault at this point, so that beyond the spot where I stood the strata had slipped down a matter of twenty feet.  The result was that the continuation of my ledge lay twenty feet below me, where it ended as abruptly as did the end upon which I stood.

And here, evidently halted in flight by this insurmountable break in the ledge, stood the object of the creature’s attack—­a girl cowering upon the narrow platform, her face buried in her arms, as though to shut out the sight of the frightful death which hovered just above her.

The dragon was circling lower, and seemed about to dart in upon its prey.  There was no time to be lost, scarce an instant in which to weigh the possible chances that I had against the awfully armed creature; but the sight of that frightened girl below me called out to all that was best in me, and the instinct for protection of the other sex, which nearly must have equaled the instinct of self-preservation in primeval man, drew me to the girl’s side like an irresistible magnet.