He gave orders to this effect to one of the watchmen and then with Ned went to the place, outside the fence, where Tom had last talked with his chum. But it was dark, and Ned, naturally, could not point out the exact spot, even with the aid of a flashlight. “I think it was here, near this rock and bush,” he said, throwing the gleam of his little electric torch about. But the dry, hard ground gave no clews to this superficial examination, and, as a matter of fact, Ned was about twenty-five feet off in his calculations, as was demonstrated later. Otherwise he and Mr. Swift might have seen the hole in the ground and the flight of stairs, for it was not until some time later that night—near morning, as a matter of fact—that the plotters replaced the planks and spread earth over them, thus hiding the secret entrance. “Well, there doesn’t seem to be anything here,” said Mr. Swift, with an uneasy sigh as they made a hasty examination of the place. “We had better go inside and look there.” But the search in and about the many buildings of the great Swift plant was no more successful. Every office and shop telephone had been rung. Some were answered by guards or watchmen who happened to be in the vicinity at the time the bell rang. But one and all said they had not seen Tom. Then there was a check-up of every gate and entrance in the big fence, and at no place had Tom been admitted. Granting that his protective plans worked, he could not have entered his own plant without a record having been made of it, and there was none. “There’s only one answer to this, then,” said Ned, when the search had ended. “What’s the answer?” asked Mr. Swift. “Tom didn’t come in here after he left me. He must have gone somewhere else.” Mr. Swift looked at his watch. “Do you suppose he could be at Mary’s now?” he asked. “What time is it?” “Three.” “No, he wouldn’t be there at this hour!” declared Ned. “He might,” replied Mr. Swift hopefully. “When Tom’s mind is busy on his inventions he forgets all about time. It would be just like him to forget that it was three o’clock in the morning and go to call on Mary.” Ned shook his head, but Mr. Swift went on: “I’m going to call her presently. But there is just one more place I want to search. It’s in the vault where we keep the Chest of Secrets, as Tom calls it. There is a private entrance to that he could come in by and not register the alarm nor be seen by any of the guards. He can switch off that alarm from his room at the house. I’ll look there. He may have gone there to see if there isn’t some way out in the trouble we’re in over the airline express patents.” “Trouble?” questioned Ned, as they walked toward the vault.