“Well of all things!” cried Mr. Damon.  “What are you up to now, Tom Swift?”

“It’s my noiseless airship,” explained our hero.  “She doesn’t make a sound.  Get aboard, and have a ride.”

Mr. Damon looked toward the house.

“I guess my wife won’t see me,” he said with a chuckle.  “She’s more than ever opposed to airships, Tom, since we went on that trip taking moving pictures.  But I’ll take a chance.”  And in he sprang, when the two lads started up again.  They made quite a flight, and Tom found that his new motor exceeded his expectations.  True, it needed some adjustments, but these could easily be made.

“Well, what are you going to do with it, now that you have it?” asked Mr. Damon, as Tom once more brought the machine around to the odd man’s house, and stopped it.  “What’s it for?”

“Oh, I think I’ll find a use for it,” replied the young inventor.  “Will you come back to Shopton with us?”

“No, I must stay here.  I have some letters to write.  But I’ll run over in a few days, and see you.  Then I’ll go on another trip, if you’ve got one planned.”

“I may have,” answered Tom with a laugh.  “Good-bye.”

He and Ned made a quick flight home, and Tom at once started on making some changes in the motor.  He was engaged at this work the next day, when he noticed a shadow pass across an open window.  He looked up to see Ned.

“Hello, Tom!” cried his chum.  “Have you heard the news?”

“No, what news?  Has Andy Foger fallen out of his airship?”

“No, but there are a whole lot of Custom House detectives in town, looking for clews to the smugglers.”

“Still at it, eh?  Shopton can’t seem to keep out of the limelight.  Has anything new turned up?”

“Yes.  I just met Mr. Whitford.  He’s back on the case and he has several men with him.  They received word that some smuggled goods came to Shopton, and were shipped out of here again.”

“How, by airship?”

“No, by horse and wagon.  A lot of cases of valuable silks imported from England to Canada, where the duty is light, were slipped over the border somehow, in airships, it is thought.  Then they came here by freight, labeled as calico, and when they reached this town they were taken away in a wagon.”

“But how did they get here?”

“On the railroad, of course, but the freight people had no reason to suspect them.”

“And where were they taken from the freight station?”

“That’s what the customs authorities want to find out.  They think there’s some secret place here, where the goods are stored and reshipped.  That’s why so many detectives are here.  They are after the smugglers hot-footed.”

CHAPTER V

THE RAID

Tom Swift dropped the tool he was using, and came over to where Ned stood, his chum having vaulted in through the open window.