Tom nodded. "I'll fetch you the money right away," he said, starting for his room. He got the cash from a small safe he had arranged, which was fitted up with an ingenious burglar alarm, and was on his way downstairs when he heard his father call out: "Here! What do you want? Go away from that shop! No one is allowed there!" and looking from an upper window, Tom saw his father running toward a stranger, who was just stepping inside the shop where Mr. Swift was constructing his turbine motor. Tom started as he saw that the stranger was the same black-mustached man whom he had noticed in the post-office, and, later, in the restaurant at Mansburg. CHAPTER V. MR. SWIFT IS ALARMED Stuffing the money which he intended to give to Mr. Damon in his pocket, Tom ran downstairs. As he passed through the living-room, intending to see what the disturbance was about, and, if necessary, aid his father, the owner of the broken motor-cycle exclaimed: "What's the matter? What has happened? Bless my coat-tails, but is anything wrong?" "I don't know," answered Tom. "There is a stranger about the shop, and my father never allows that. I'll be back in a minute." "Take your time," advised the somewhat eccentric Mr. Damon. "I find my legs are a bit weaker than I suspected, and I will be glad to rest a while longer. Bless my shoelaces, but don't hurry!" Tom went into the rear yard, where the shops, in a small cluster of buildings, were located. He saw his father confronting the man with the black mustache, and Mr. Swift was saying: "What do you want? I allow no people to come in here unless I or my son invites them. Did you wish to see me?" "Are you Mr. Barton Swift?" asked the man. "Yes, that is my name." "The inventor of the Swift safety lamp, and the turbine motor?" At the mention of the motor Mr. Swift started. "I am the inventor of the safety lamp you mention," he said stiffly, "but I must decline to talk about the motor. May I ask where you obtained your information concerning it?" "Why, I am not at liberty to tell," went on the man. "I called to see if we could negotiate with you for the sale of it. Parties whom I represent--" At that moment Tom plucked his father by the sleeve. "Dad," whispered the youth, "I saw him in Mansburg. I think he is one of several who have been inquiring in Mr. Merton's shop about you and your patents. I wouldn't have anything to do with him until I found out more about him." "Is that so?" asked Mr. Swift quickly. Then, turning to the stranger, he said: "My son tells me--" But Mr. Swift got no further, for at that moment the stranger caught sight of Tom, whom he had not noticed before. "Ha!" exclaimed the man. "I have forgotten something--an important engagement--will be back directly--will see you again, Mr. Swift--excuse the trouble I have put you to--I am in a great hurry," and before father or son could stop him, had they any desire to, the man turned and walked quickly from the yard.