“Mr. Damon,” said Tom quickly, “will you sell me that motor-cycle?”

“Bless my finger rings!  Sell you that mass of junk?”

“It isn’t all junk,” went on the young inventor.  “I can easily fix it; though, of course,” he added prudently, “it will cost something.  How much would you want for it?”

“Well,” replied Mr. Damon, “I paid two hundred and fifty dollars last week.  I have ridden a hundred miles on it.  That is at the rate of two dollars and a half a mile—­pretty expensive riding.  But if you are in earnest I will let you have the machine for fifty dollars, and then I fear that I will be taking advantage of you.”

“I’ll give you fifty dollars,” said Tom quickly, and Mr. Damon exclaimed: 

“Bless my liver—­that is, if I have one.  Do you mean it?”

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?”