“Yes. Tom and I haven’t spoken of it even to you, Ned, for the thing really isn’t in such shape that it can be talked about. But Tom has an idea, it may be nothing more than a dream, that he can establish a line of travel to cross our continent from New York to San Francisco between dawn and darkness. In other words, a coast-to-coast service, from ocean to ocean, by daylight—say sixteen hours—with no change.” “No change!” cried Ned. “What’s the idea—refueling the planes in the air? Of course that has been done. But from coast to coast in sixteen hours without change! It can’t be done!” “Tom thinks so,” said Mr. Swift. “That’s what he’s working on now. He has had some new models made, but there is trouble over the patent rights. Some one is trying to get his idea away from him. It may be that Tom came to the secret vault after he left you to make sure everything was all right, and he may be there yet.” But the vault was unoccupied, nor had it been disturbed. Mr. Swift gave a hasty glance at several complicated and odd-looking models of aircraft in the concrete room, looked over a pile of papers, and said: “Well, they haven’t been disturbed since Tom and I were here last, which proves my son hasn’t been here. But where is he? I’m beginning to get worried, Ned. More worried than ever!” “Oh, he’ll be all right,” was the answer, though in his own heart Ned Newton could not help feeling apprehensive. “It may be, as you say, that he made a very late call on Mary, and her folks have probably asked him to stay all night, as they have done before.” “I think the matter justifies me in calling Mr. Nestor on the telephone,” said Mr. Swift, as they emerged from the vault where the Chest of Secrets was stored. “It’s rather early to ring up anybody, but I guess they will understand.” It was about four o’clock now, and already, in the east, a light was appearing, the sun was heralding the dawn. The early birds were beginning to sing. It would soon be morning, though not yet time for the wheels to begin humming in the Swift plant. Going back to the office, where Koku reported that a second check-up had failed to disclose the whereabouts of the young inventor, Mr. Swift called the Shopton central operator and gave her the number of the Nestor house. There was some little delay, as was natural when a call is made at that hour of the morning, but at length Mr. Nestor’s voice was heard. “Who? Tom? No, he isn’t here—hasn’t been here,” was the message the aged inventor received. “What’s the matter?” There was some further talk, and Mr. Swift briefly outlined what had happened. “Don’t alarm Mary yet,” Mr. Swift cautioned his friend. “But I fear something has happened to Tom. I wish you would come over.” “I will!” Mr. Nestor promised. “I’ll be over as soon as I can dress.” “Tell him I’ll call for him,” Ned said to Mr. Swift, and this message went over the wires.