"He's probably conversing with Fekmah," was the opinion expressed by Mr. Lewis. "You know," he went on, "that Arab is a strange contrast to these worthless fellows around here. It all goes to show what anyone can do if he wants to." "He's educated, too, isn't he?" inquired Joe. "Yes, highly," the naturalist replied. "Was graduated from the University of Algiers and received a degree. What he doesn't know isn't worth knowing." "Where is his home?" asked Bob. "He doesn't live in Algiers, does he?" "No. He lives in Oran; that's about a hundred and twenty-five miles or so west of here. Quite a prosperous city, I guess." "But," questioned Bob, thoroughly puzzled, "what is he doing here in Algiers?" "It all goes back to Dr. Kirshner's conversation with him on the ship," Mr. Holton explained. "You see, Tom"--referring to the archæologist--"met him on the last day of the voyage and recognized him to be a very intellectual man. As soon as Fekmah found that he could trust Kirshner, he confided this secret about the hidden riches. Well, then, when he found that we would accept his proposition and make it one of the objects of the expedition to search for this treasure, Fekmah put up at a hotel in Algiers in order to accompany us into the Sahara. See?" "Sure. I don't know now why I didn't before." They were now among the lights of Algiers, and Joe headed straight for the business section, where the car was to be returned to the garage. They reached the place in a short time and left the automobile. Then they hurried around to their hotel. When they came to their room, they found Dr. Kirshner and Fekmah in earnest conversation. When the two heard their friends in the hall, they arose, wreathed in smiles. "We have good news for you," announced Dr. Kirshner joyously. "The train is leaving for Wargla in the morning." CHAPTER VIII Off for the Sahara "Hurrah!" burst out Joe, overwhelmed with delight. "We'll get ahead of those crooks after all." "When did you find out?" asked Mr. Holton, as overjoyed as the youth. "Late this afternoon," was the response. "We intended to make frequent trips to the railroad station in order to know as soon as possible. The agent there informed us that the track had been cleared last night and the locomotive repaired this morning. He didn't give the impression that there are other trains on this route, but I suppose there are." "That's fine!" exclaimed Mr. Lewis, as excited as a boy. "We'll get a meal at once and then complete preparations for the journey. Have you two eaten?" "Yes," returned Fekmah. "It is getting late. Six, seven o'clock." The naturalists and their sons made their way to the café and did full justice to a delicious meal. Then they went back to their room and finished packing their possessions. "Do you know," remarked Joe that night just before retiring, "we were, in a sense, responsible for that train wreck?" Bob looked up in surprise.