"I was just recalling a portion of Hal's cousin's diary," his father replied. "According to that, it seems that rough characters visit this place sometimes."

"Oh, we're not afraid," Hal protested. "Besides, you could make the trip there and back in a few hours."

"Well, we'll think it over and decide in the morning what we'll do," said Mr. Perry.

"Meanwhile, I tell you what we ought to do," Bud proposed. "It's an hour before dark and we'd have time to bring Hal's wireless outfit up here and hook it up before the sun sets."

"That's a peach of an idea," declared Cub, jumping to his feet in his eagerness. "I've got two hundred and fifty feet of extra wire and some insulators on the boat and we can put up an aerial here without taking down the one on the Catwhisker. Then we can shift the radio outfit back and forth to the island and to the boat as we please."

"Good!" exclaimed Hal. "I'm with you on that. Let's get busy and not waste a minute of daylight."

They worked rapidly, and as they were well supplied with material and tools the progress made by them measured up to expectations. They fashioned a two-wire antenna with the spreaders left on the island by Hal's cousin; connected a lead-in to this, and then Cub and Bud climbed the two trees and, with the aid of ropes tied around their waists and the guiding a.s.sistance of their companions below, drew the "ether-wave feeler" up to a lofty elevation and fastened it as nearly taut as they could stretch and hold it. In this work they took due consideration of the professional objection to tree entanglements in aerials so that the insulators were well beyond the reach of the longest limbs.

"It's a simple matter now to bring the outfit ash.o.r.e and hook it up with the aerial," said Hal. "Let's do it."

Enthused by the novelty of their enterprise, they continued the work, even though dusk was rapidly gathering. Several electric-battery flash-lights were produced, so that the twilight did not seriously hinder them. By the time the stars had become a billion glittering gems in the sky, the hook-up had been completed with Hal's sending and receiving set on a table that had been transported from the yacht to a convenient position directly under the aerial and near the opening of the tent.

"Now, let's see what's going on in the air," said Cub. "Hal, you take the first whirl through the atmosphere."

Hal sat down by the table and put a pair of phones to his ears. Then he began to tune. First there came to him a discordant confusion of static and other noises, including an admixture of "ham impudence".

"W H Q's on," announced Hal presently, pushing over the horn switch, whereupon the clear tones of a quartet from the Rochester station was thrown with amplified resonance out upon the reamplifying atmosphere of a land-and-water wilderness.

They "sat through" the program with a degree of enjoyment never before experienced by them under a radio spell. They could almost imagine themselves on an enchanted isle with a band of fairy songsters teasing harmonious echoes out of their surroundings.

"My! I didn't suppose such weird beauty of sound could be produced under any possible conditions," exclaimed Mr. Perry at the close of the last number on the program.

"Now the air will be free for all for a short time," said Hal, putting on the phones and throwing back the horn switch, while the other boys also donned their phones. "I'm going to see if I can get any of those fellows we talked with on the way up here."

"Get that amateur with the radio compa.s.s who proved Mr. Perry's mathematical theory," suggested Bud.

"All right I remember his call and wave length; so here goes."

Hal tuned for several moments and sent the call of the Canadian amateur in question. Then suddenly he gave a little gasp of surprise. Only Mr.

Perry felt a curiosity as to what it meant, for the other two boys knew as soon did the boy at the transmitting key. Someone was calling them and the call he gave as his own was the Canadian V A X. Then came the following message:

"Have you not given it up yet, boys? I did not mean to carry the joke so far. Better go back home."

Mr. Perry was waiting patiently for an explanation of the tense interest manifest in the att.i.tudes of the three boys. Presently Cub gave it to him, thus:

"We're on the trail again, dad. This fellow we've got is posing as Hal's cousin and he's advising us to go back home."

CHAPTER XVI

Running Down a Radio Fake

"You say you are V A X?" dot-and-dashed Hal to the amateur who had thus represented himself.

"Yes," was the reply.

"What is your name?"

"Alvin Baker."

"Where do you live?"

"At Port Hope."

"Where are you now?"

"On the river with some friends."

"Have you any relatives in the United States?"

"Yes."

"Where do they live?"

"In New York."

"New York City?"

"No--State."

"What city?"

"I have forgotten."

"Is it Rochester?"

"I do not know."

"Is it Oswego?"

"I am not certain."

"Have you a cousin named Hal?"

"Yes."

"What is his last name?"

"Baker."

"Have you any relatives named Stone?"