“Yes, Tom it certainly is a wonderful invention.  I congratulate you,” and, at the same time he winked rapidly at our hero.  Tom winked in return.

“Well, I guess we’ll start back,” remarked Tom, after a bit.  “I’ll see you again, I suppose, Mr. Damon?”

“Oh yes, of course.  I’ll be over—­soon,” and once more he winked as he whispered in Tom’s ear:  “Don’t leave me behind, my boy.”

“I won’t,” whispered the young inventor in answer.

Mrs. Damon smiled, and Tom wondered if she had discovered her husband’s innocent secret.

Tom and Ned, with Koku, made a quick trip back to Shopton, using the great searchlight part of the way.  The next day they began preparations for the journey to the border.

It did not take long to get ready.  No great amount of stores or supplies need be taken along, as they would not be far from home, not more than a two days’ journey at any time.  And they would be near large cities, where food and gasolene could easily be obtained.

About a week later, therefore, Mr. Whitford the government agent, having been communicated with in the meanwhile, Tom and Ned, with Koku and Mr. Damon were ready to start.

“I wonder if Mr. Whitford is coming to see us off?” mused Tom, as he looked to see if everything was aboard, and made sure that the searchlight was well protected by its waterproof cover.

“He said he’d be here,” spoke Ned.

“Well, it’s past time now.  I don’t know whether to start, or to wait.”

“Wait a few minutes more,” advised Ned.  “His train may be a few minutes behind time.”

They waited half an hour, and Tom was on the point of starting when a messenger boy came hurrying into the yard where the great airship rested on its bicycle wheels.

“A telegram for you, Tom,” called the lad, who was well acquainted with our hero.

Hastily the young inventor tore open the envelope.

“Here’s news!” he exclaimed,

“What is it?” asked Ned.

“It’s from Mr. Whitford,” answered his chum.  “He says:  ’Can’t be with you at start.  Will meet you in Logansville.  Have new clew to the Fogers!’”

“Great Scott!” cried Ned, staring at his chum.

CHAPTER XI

ANDY’S NEW AIRSHIP

Tom Swift tossed a quarter to the messenger boy, and leaped over the rail to the deck of his airship, making his way toward the pilot house.

“Start the motor, Ned,” he called.  “Are you all ready, Mr. Damon?”

“Bless my ancient history, yes.  But—­”

“Are you going, Tom?” asked Ned.

“Of course.  That’s why we’re here; isn’t it?  We’re going to start for the border to catch the smugglers.  Give me full speed, I want the motor to warm up.”

“But that message from Mr. Whitford?  He says he has a new clew to the Fogers.”

“That’s all right.  He may have, but he doesn’t ask us to work it up.  He says he will meet us in Logansville, and he can’t if we don’t go there.  We’re off for Logansville.  Good-bye dad.  I’ll bring you back a souvenir, Mrs. Baggert,” he called to the housekeeper.  “Sorry you’re not coming, Rad, but I’ll take you next time.”