“Well, my Arab had a mole on his chin, and that is why I am sure it was he that I saw a minute ago—over there. No, he’s gone now!”

The competing horsemen appeared round the bend for the last time, the dancing-girls whinnied in their high treble, the crowd roared, and the Prix de la Ville was won and lost. It was the final race on the card, and in the mêlée which followed, Cecil became separated from his adorer. She was to depart on the morrow by the six a.m. train. “Urgent business,” she said. She had given up the chase of the millionaire. “Perhaps she’s out of funds, poor thing!” he reflected. “Anyhow, I hope I may never see her again.” As a matter of fact he never did see her again. She passed out of his life as casually as she had come into it.

He strolled slowly towards the hotel through the perturbed crowd of Arabs, Europeans, carriages, camels, horses and motor-cars. The mounted tribesmen were in a state of intense excitement, and were continually burning powder in that mad fashion which seems to afford a peculiar joy to the Arab soul. From time to time a tribesman would break out of the ranks of his clan, and, spurring his horse and dropping the reins on the animal’s neck, would fire revolvers from both hands as he flew over the rough ground. It was unrivalled horsemanship, and Cecil admired immensely the manner in which, at the end of the frenzied performance, these men, drunk with powder, would wheel their horses sharply while at full gallop, and stop dead.

And then, as one man, who had passed him like a hurricane, turned, paused, and jogged back to his tribe, Cecil saw that he had a mole on his chin. He stood still to watch the splendid fellow, and he noticed something far more important than the mole—he perceived that the revolver in the man’s right hand had a chased butt.

“I can’t swear to it,” Cecil mused. “But if that isn’t my revolver, stolen from under my pillow at the Hôtel St. James, Algiers, on the tenth of January last, my name is Norval, and not Thorold.”

And the whole edifice of his ideas concerning the robbery at the Hôtel de Paris began to shake.

“That revolver ought to be at the bottom of the Mediterranean,” he said to himself; “and so ought Mrs. Macalister’s man with the mole, according to the accepted theory of the crime and the story of the survivors of the shipwreck of the Perroquet Vert.”

He walked on, keeping the man in sight.

“Suppose,” he murmured—“suppose all that stuff isn’t at the bottom of the Mediterranean after all?”

A hundred yards further on, he happened to meet one of the white-clad native guides attached to the Royal Hotel where he had lunched. The guide saluted and offered service, as all the Biskra guides do on all occasions. Cecil’s reply was to point out the man with the mole.