"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?"

"I'll come to that, presently," replied Mr. Whitford. "In the first