Eh bien! Let us investigate,” he said, evidently amazed at my very detailed word-picture of the place. “Let us see how far you are correct. For ten minutes you’ve been gazing at it with such a strange, far-off look in your eyes, that I confess I began to be concerned as to your sanity. I have seen a similar look in the eyes of Chasseurs who have fallen victims to sunstroke.”

“The mystery is just as inexplicable to myself as it is to you,” I answered. “Somehow, however, the contact of the Crescent has created within me a firmly-rooted conviction that we shall discover something in that cavern.”

“If we can find the place,” he added, laughing good-humouredly.

“Let us try,” I said, climbing upon my camel, who had been resting on his knees a few yards away, and causing him to rise. Uzanne, after another pull at his water-skin, sprang upon his horse, and we both commenced to descend again to the sandy plain.

With eyes fixed upon the mountain, rising like an island amid that inhospitable sea of sand, we pressed forward, Uzanne from time to time expressing a hope that we were not seeking a will-o’-the-wisp, and speculating as to what mystery might be concealed within the gloomy opening I had described. The way grew more rough, sand being succeeded by great sharp stones, which played havoc with my camel’s feet, causing me to travel but slowly, for my animal’s lameness in this vast wilderness might result disastrously. Still we journeyed on, as slowly the great mountain assumed larger proportions, until, after a most tedious course of travel, we found ourselves but a few hundred yards from its base.

The three trees were growing upon the summit as I had seen them in my mental picture, and every detail was the same in reality as I had witnessed it. The ground rose gently, with palmetto and asphodel growing and flourishing among the rocks, but there was no steep cliff of granite—there was no cave!

Uzanne laughed at my abject disappointment.

“My surmise was correct, you see, old fellow,” he exclaimed, pulling up for a moment to light a cigarette. “The mysterious cavern only existed in your distorted imagination.”

“But how do you account for the fact that I was able to describe the place to you before I had seen it?”

Shrugging his shoulders with the air of the true Parisian, he answered, “There are mysteries that it would be futile to attempt to fathom. That is one.”