lone camel-driver came flogging his beast into Ouargla shouting that the day of judgment was at hand and Allah had come for his faithful. He had seen over the mirage city a flash of lightning and heard the roar of thunder. Now there are some cities in the Sahara where it rains occasionally, say on an average of once in twelve years, but south of Ouargla it has not rained in the memory of living man, nor is there any account of rain handed down in the folk-lore of the people. And yet each August when the summer sirocco blew up out of that trackless eastern waste of sand wherein moves no living thing, there were those of keen nostrils in Ouargla who said they had caught in that searing breath sweetly sickish odors as of crushed lilies and rotting fruits.
All this had come to the ears of Professor Lorne. He was at that time pottering about Shott el Jerid, the salt swamps south of Tunis, working on the Borchardt theory that the lost Atlantis had once been located there. With him was his daughter, Constance, and her betrothed, Colin Penfield. I came into the story when I ran across them in a Tunis hotel and being hot for adventure begged the professor to take me with him on the expedition he was then planning. As I was something of a topographer, having served in that capacity with both the American and French armies during the war, he was glad to take me on.
I had heard of the Ouargla mirage. Is there anyone who ever set foot on the shores of North Africa who hasn't? But I confess that when he had revealed his project to me in full I was a little cold. It was too fantastic. It seems he was a believer in the theory that a mirage is the reflection of some far-distant object. Therefore, he reasoned, if there were such a mirage to be seen from Djerija, then there must be somewhere down in the desert a great mysterious city of which we knew nothing. With an instrument which he had recently invented he claimed he could, by sighting on the mirage, obtain the latitude and longitude of the lost city.
I came to realize then that he believed the mirage city not only existed but that it was the lost Atlantis of which he had already found traces in Shott el Jerid below Tunis.
"Plato's description has misled modern scientists concerning the location of Atlantis," said he. "We locate it beyond Gibraltar, which we believe to be the Pillar of Hercules, but as a matter of fact these are two distinct points separated by hundreds of miles. The real Pillar of Hercules, as known by the ancients, was located far east and south of Syrtis Major in the vicinity of Ahag- gar Massif, to which Ptolemy refers in Mons Talae. Atlantis sank to an. unknown depth in 1250 B. C. during a terrific terrestrial upheaval which, according to Diodorous, the Greek historian, swept the tectonic area lying between Teneriffe and Sicily. But the inhabitants, warned of the impending catastrophe, fled inland and disappeared in the desert. I have no doubt, now, that this great city which we see mirrored in the skies was built by them. Its remarkable state of preservation, as evidenced by the mirage, is probably due to the extreme dryness of the desert atmosphere."
"But the palm trees and the odors they tell about," put in Constance Lorne; "how could they come out of a desert waste?"
"The odors are imagination," he replied, "and none but the Arabs have seen the palms. They are probably mistaken. And anyway, what's to prevent our believing that there may not be some great oasis there?"
The upshot of it was that we all went down to Djerija. There in the
