ission.

"Oh, I'll see that you get the proper authority all right," said Mr.
Whitford significantly. "I made you a temporary deputy to-night, but
if you'll undertake this work, to catch the smugglers in their
airships, you will be made a regular custom official."

"Yes, but supposing I can't catch them?" interposed our hero. "They
may have very fast airships, and--"

"I guess you'll catch 'em all right!" put in Ned, who was at his
chum's side as they walked along a quiet Shopton street in the
darkness. "There's not an aeroplane going that can beat yours, Tom."

"Well, perhaps I COULD get them," admitted the young inventor. "But--"

"Then you'll undertake this work for Uncle Sam?" interrupted Mr.
Whitford eagerly. "Come, Tom, I know you will."

"I'm not so sure of that," spoke Tom. "It isn't going to be as easy
as you think. There are many difficulties in the way. In the first
place the smuggling may be done over such a wide area that it would
need a whole fleet of airships to capture even one of the others,
for they might choose a most unfrequented place to cross the
border."

"Oh, we would be in communication with you," said the agent. "We can
come pretty near telling where the contrabrand goods will be shipped
from, but the trouble is, after we get our tips, we can't get to the
place before they have flown away. But with your airship, you could
catch them, after we sent you, say a wireless message, about where
to look for them. So that's no objection. You have a wireless outfit
on your airships, haven't you, Tom?"

"Yes, that part is all right."

"Then you can't have any more objections, Tom."

"Well, there are some. For instance you say most of this smuggling
is done at night."

"Practically all of it, yes."

"Well, it isn't going to be easy to pick out a contraband airship in
the dark, and chase it. But I'll tell you what I'll do, Mr.
Whitford, I feel as if I had sort of 'fallen down' on this clew
business, as the newspaper men say, and I owe it to you to make good
in some way."

"That's what I want--not that I think you haven't done all you
could," interposed the agent.

"Well, if I can figure out some way, by which I think I can come
anywhere near catching these smugglers, I'll undertake the work!"
exclaimed Tom. "I'll do it as a duty to Uncle Sam, and I don't want
any reward except my expenses. It's going to cost considerable, but--"

"Don't mind the expense!" interrupted Mr. Whitford. "Uncle