er he had altered two important units of the device, a new note came
to his ears through the "watch-case" receivers that were clamped to his
head.

"It's code--somebody sending code!" exclaimed Jack, and then the next
instant, "it's some ship of the navy! Hurrah! The detector is working,
for they use different wave lengths from the commercial workers, and, if
it hadn't been for the Universal Detector, I'd never have been able to
listen in at their little talk-fest."

He waited till the code message, a long one from Washington to the
_Idaho_, of the North Atlantic fleet at Guantanamo, Cuba, was finished,
and then he could not refrain from "butting in."

"Hello, navy," he chattered with the wireless key, "that was a nice
little message you had. How's the weather up your way?"

"Who is this?" demanded the navy wireless in imperious tones.

"Oh, just a fellow who was listening," responded Jack.

"Butting in, you mean. But say, how did you ever get on to our sending?
We were using eccentric wave-lengths to keep our talk a secret."

"I'll have to keep how I caught your talk a secret, too, for the
present, old man."

"Great Scott! It isn't possible that you've solved the problem of a
universal detector. Why, that's a thing the navy sharps have been
working on for years."

"I can't say how I caught your message," shot back Jack's radio through
space.

"You'll have to tell if the government gets after you," was the reply.
"Uncle Sam isn't going to have a fellow running round loose with
anything like that."

"What do you mean?"

"That you will be forbidden to use it."

"Is that so?"

"Yes, that's so. I'm going to make out a report for my superiors about
it right now. You're pretty fresh."

"Put that in the report, too," chuckled the _Columbia's_ wireless
disdainfully.

"You'll find it's no joke to monkey with the government," snapped back
the naval man.

Jack didn't answer. A message from the _Taurus_, of the Bull Line, was
coming in. She had sighted an iceberg, something very unusual at that
time of year. Jack hurried the message, which gave latitude and
longitude of the menace, to Captain Turner.

"Well, that won't bother us," said that dignitary. "We're far to the
south of that. Those Bull fellows run to Quebec. Send a radio to Captain
Spencer, of the _Taurus_, thanking him for his information."

The great man, the captain of a liner, who has literally more power than
a king, lit a cigar, and bent his