pying on me. If you don't care to accept my offer, like a
gentleman, tell me who you are, and what your object is, I will have
my assistant remove you. You are on private property, as this street
is not a public one, being cut through by my father. I'll have Koku
remove you by force, if you won't go peaceably, and I think you'll
agree with me that Koku can do it. Here Koku," he called sharply,
and the big man advanced quickly.

"I wouldn't do anything rash, if I were you," said the man quietly.
"As for this being private property, that doesn't concern me. You're
Tom Swift, aren't you; and you have several airships?"

"Yes, but what right have you to--"

"Every right!" interrupted the man, throwing back the lapel of his
coat, and showing a badge. "I'm Special Agent William Whitford, of
the United States Customs force, and I'd like to ask you a few
questions, Tom Swift." He looked our hero full in the face.

"Customs department!" gasped Tom. "You want to ask me some
questions?"

"That's it," went on the man, in a business-like voice.

"What about?"

"Smuggling by airship from Canada!"

"What!" cried Tom. "Do you mean to say you suspect me of being
implicated in--"

"Now go easy," advised the man calmly. "I didn't say anything,
except that I wanted to QUESTION you. If you'd like me to do it out
here, why I can. But as someone might hear us--"

"Come inside," said Tom quietly, though his heart was beating in a
tumult. "You may go, Koku, but stay within call," he added
significantly. "Come on, Ned," and he motioned to his chum who was
approaching. "This man is a custom officer and not a spy or a
detective, as we thought."

"Oh, yes, I am a SORT of a detective," corrected Mr. Whitford. "And
I'm a spy, too, in a way, for I've been spying on you, and some
other parties in town. But you may be able to explain everything,"
he added, as he took a seat in the library between Ned and Tom. "I
only know I was sent here to do certain work, and I'm going to do
it. I wanted to make some observations before you saw me, but I
wasn't quite quick enough."

"Would you mind telling me what you want to know?" asked Tom, a bit
impatiently. "You mentioned smuggling, and--"

"Smuggling!" interrupted Ned.

"Yes, over from Canada. Maybe you have seen something in the papers
about our department thinking airships were used at night to slip
the goods over the border."

"We saw it!" cried Tom eagerly. "But how does that concern me?