“Bless my—­” began Mr. Damon, but in the excitement he really didn’t know what to bless, so he stopped short.

A moment later, feeling that the momentum had been checked enough to make it safe to land, Tom directed the craft downward again and came gracefully to earth, a short distance away from his eccentric friend.

“Whew!” gasped the young inventor, as he leaped from his seat.  “That was a scary time while it lasted.”

“I should say so!” agreed Ned.

“Bless my straw hat!” cried Mr. Damon.  “What happened?  Did you lose control of her, Tom,”

“No, the deflecting rudder got jammed, and I couldn’t move it.  I must look and see what’s the matter.”

“I thought it was all up with you,” commented Mr. Damon, as he followed Tom and Ned to the front end of the craft, where the deflecting mechanism was located.

Tom glanced quickly over it.  His quick eye caught something, and he uttered an exclamation.

“Look!” the young inventor cried.  “No wonder it jammed!” and from a copper sleeve, through which ran the wire that worked the rudder, he pulled a small iron bolt.  “That got between the sleeve and the wire, and I couldn’t move it,” he explained.  “But when I pulled hard I loosened it.”

“How did it fall in there?” asked Ned.

“It didn’t fall there.” spoke Tom quietly.  “It was put there.”

“Put there!  Bless my insurance policy!  Who did such a dastardly trick?” cried Mr. Damon.

“I don’t know,” answered Tom still quietly, “but I suspect it was Andy Foger, and he was never any nearer to putting us out of business than a little while ago, Ned.”

“Do you mean to say that he deliberately tried to injure you?” asked Mr. Damon.

“Well, he may not have intended to hurt us, but that’s what would have happened if I hadn’t been able to throw her up into the wind when I did,” replied Tom.  Then he told of Mr. Swift having seen the red-haired bully near the aeroplane.  “Andy may have only intended to put my machine out of working order,” went on the young inventor, “but it might have been worse than that,” and he could not repress a shudder.

“Are you going to say anything to him?” asked Ned.

“I certainly am!” replied Torn quickly.  “He doesn’t realize that he might have crippled us both for life.  I sure am going to say something to him when I get back.”

But Tom did not get the chance, for when he and Ned returned to Shopton,—­the sky racer behaving beautifully on the homeward trip,—­ it was learned that Mr. Foger had suddenly left town, taking Andy with him.

“Maybe he knew I’d be after him,” said Tom grimly, and so that incident was closed for the time being, but it was a long time before Tom and Ned got over their fright.

They had a nice visit with Mr. Damon, and talked of the city of gold to their heart’s content, looking at several large maps of Mexico that the eccentric man had procured, and locating, as well as they could from the meager map and description they had, where the underground treasures might be.