That night we pitched our camp immediately under the cliff—­a most wild and desolate spot.  The crags above us were not merely perpendicular, but curved outwards at the top, so that ascent was out of the question.  Close to us was the high thin pinnacle of rock which I believe I mentioned earlier in this narrative.  It is like a broad red church spire, the top of it being level with the plateau, but a great chasm gaping between.  On the summit of it there grew one high tree.  Both pinnacle and cliff were comparatively low—­some five or six hundred feet, I should think.

“It was on that,” said Professor Challenger, pointing to this tree, “that the pterodactyl was perched.  I climbed half-way up the rock before I shot him.  I am inclined to think that a good mountaineer like myself could ascend the rock to the top, though he would, of course, be no nearer to the plateau when he had done so.”

As Challenger spoke of his pterodactyl I glanced at Professor Summerlee, and for the first time I seemed to see some signs of a dawning credulity and repentance.  There was no sneer upon his thin lips, but, on the contrary, a gray, drawn look of excitement and amazement.  Challenger saw it, too, and reveled in the first taste of victory.

“Of course,” said he, with his clumsy and ponderous sarcasm, “Professor Summerlee will understand that when I speak of a pterodactyl I mean a stork—­only it is the kind of stork which has no feathers, a leathery skin, membranous wings, and teeth in its jaws.”  He grinned and blinked and bowed until his colleague turned and walked away.

In the morning, after a frugal breakfast of coffee and manioc—­we had to be economical of our stores—­we held a council of war as to the best method of ascending to the plateau above us.

Challenger presided with a solemnity as if he were the Lord Chief Justice on the Bench.  Picture him seated upon a rock, his absurd boyish straw hat tilted on the back of his head, his supercilious eyes dominating us from under his drooping lids, his great black beard wagging as he slowly defined our present situation and our future movements.

Beneath him you might have seen the three of us—­myself, sunburnt, young, and vigorous after our open-air tramp; Summerlee, solemn but still critical, behind his eternal pipe; Lord John, as keen as a razor-edge, with his supple, alert figure leaning upon his rifle, and his eager eyes fixed eagerly upon the speaker.  Behind us were grouped the two swarthy half-breeds and the little knot of Indians, while in front and above us towered those huge, ruddy ribs of rocks which kept us from our goal.