It was two nights before the Columbia, on her homeward voyage, entered New York harbor. On the trip across she had once more had the big British greyhound of the seas for a rival. But this time there was a different tale to tell. The Columbia was coming home, as Billy Raynor put it, "with a broom at the main-mast head."

All day the wireless snapped out congratulations from the shore. Jack was kept busy transmitting shore greetings and messages from returning voyagers who had chosen the finest ship under the stars and stripes on which to return to the United States. Patriotism ran riot as every bulletin showed the Columbia reeling over two or three knots more an hour than her rival. One enthusiastic millionaire offered a twenty-dollar gold piece to every fireman, and five dollars each to all the other members of the crew, if the Columbia beat her fleet rival by a five-hour margin. The money was as good as won.

Thurman sat in the wireless room. His head was in his hands and he was thinking deeply. Should he or should he not send that message to Washington which, he was sure, would cause Jack's arrest the instant the ship docked. He had struggled with his conscience for some time. But then the thought of the reward and the fancied grudge he owed Jack overtopped every other consideration. He seized the key and began calling the big naval station.

It was not long before he got a reply, for when not talking to warships the land stations of the department use normal wave-lengths.

"Who is this?" came the question from the government man.

"It's X. Y. Z," rapped out Thurman.

This was the signature he had appended to his other messages.

"The thunder you say," spelled out the other; "we thought we'd never hear from you again."

"Well, here I am."

"So it appears. Well, are you ready to tell us who this chap is who's been mystifying us so?"

"I am."

"Great ginger, wait till I get Rear-admiral —— and Secretary —— on the 'phone. It's late but they'll get out of bed to hear this news."

But it transpired that both the officials were at a reception and Thurman was asked to wait till they could be rushed at top speed to the wireless station in automobiles. At last everything was ready and Thurman, while drops of sweat rolled down his face, rapped out his treachery and sent it flashing from the antennÆ across the sea.

"Thank you," came the reply when he had finished, "the secretary also wishes me to thank you and assure you of your reward. Secret Service men will meet the ship at the pier."

"And Jack Ready, what about him?"

"He will be taken care of. You had better proceed to Washington as soon as possible after you land."

"How much will the reward be?" greedily demanded Thurman.

"The secretary directs me to say that it will be suitable," was the rejoinder.

The next morning, when Jack came on duty, he sent a personal message to Uncle Toby via Siasconset. This was it:

Late that day he got back an answer that appeared to astonish him a good deal, for he sat knitting his brows over it for some moments.

This characteristic message occupied Jack for some moments till he thought of a reply to its rather vaguely worded contents. Then he got Siasconset and shot this through the air:

No reply came to this and Jack went off watch with the matter as much of a mystery as ever. But as Thurman came in to relieve him a sudden suspicion shot across Jack's mind. Could Thurman have——?

He recalled the night he had caught him examining the device with such care! Jack had since removed it, but in searching in the waste basket for a message discarded by mistake he had since come across what appeared to be crude sketches of the Universal Detector. If Thurman had not drawn them, Jack was at a loss to know who had. But for some mysterious reason he only smiled as he left the wireless room.

"If you've been up to any hocus-pocus business, Mr. Thurman," he said to himself, as he descended to dinner, "you are going to get the surprise of your life within a very short time."

After dinner he came back to the upper deck again, but as he gained it his attention was arrested by the scream of the wireless spark. It was a warm night and the door of the cabin was open. Jack stopped instinctively to listen to the roaring succession of dots and dashes.

"He's calling Washington," said Jack to himself as he listened.

"He's got them," he exclaimed a minute later.

"Hullo! Hullo! I guess I was right in my guess, then, after all. Oh, Thurman, what a young rascal you are."

He listened attentively as Thurman shot out his message to the National Capital. Jack repeated it in an undertone as the spark crackled and squealed.

"Do—I—get—my—reward—right—away?"

Jack actually burst, for some inexplicable reason, into a hearty laugh.

"Oh, Thurman! Thurman!" he exploded to himself. "What a badly fooled young man you are going to be."