“They said nothing as to what was the matter?”

Tom propounded the question ten minutes later as the two lads busied themselves in the after cabin of the Vagrant, stowing provisions hastily. “No, not a word. If only I could have got in communication with them again I might——”

At this point a very black, very round, very good-natured negro countenance appeared in the companion way above them.

“Ah’se done locked up, Marse Tom. Anyfing else yo’ all might be requirmentin’ ob?”

“No, Jupe. I guess we’re about ready for a start. Let’s see,” and Jack rapidly ran over a mental list of what they had on board.

“Yes, we’ve got everything. The water tanks are full, plenty of gasolene,—it’s a good thing we brought that extra stock from Galveston,—grub, O. K., and—better get forward and start the motor up, Tom.”

Tom needed no second bidding. He shot up the companion way three steps at a time, almost upsetting Jupe, who stood at the summit on deck. He scurried to a hatchway forward of amidships and dived below. A hasty glance over the forty horse-power, four-cylindered, four-cycle engine showed him that everything was in working order. An adjustment of the force-feed lubricator, a swift examination of the magneto, a few turns of the starting apparatus, and a rhythmic series of explosions as the crank shaft began to revolve, and the Vagrant was ready, so far as her machinery was concerned, to begin her dash across the Gulf.

In the meantime, Jupe had been hustled ashore by Jack, who had taken up his position at the wheel, and in a very few seconds the lines that held the motor cruiser to the wharf were cast off. Jupe made a flying leap aboard as the tide swung the Vagrant from her resting place.

At the same instant Jack jerked the bell pull, which signaled Tom in the engine-room below to throw in the clutch, and as the propeller began to revolve the Vagrant backed slowly out. In a few minutes Jack rang in the “Go-ahead” signal, and swinging the doughty little craft in a short semicircle, the young captain headed her almost due S.E.

Tom emerged on deck wiping his hands on a bit of waste.

“Everything all right below?” inquired Jack as his cousin took up a position beside him.

“Running like a dollar watch,” was the response.

“How much speed can we get?”

“Well, twelve knots is her registered gait, but I might coax a bit more out of her.”

“Try and get all you can.”

“I will. What time do you think we ought to reach the vicinity of the Sea King?”

“It’s a trifle over a hundred miles to the spot at which she gave her bearings,” was the response, with a glance at the chart which lay exposed in the uncovered case in front of the wheel. “It’s now just one o’clock. Say, about midnight.”

“Phew! You propose to pick up a yacht, whose location you know only vaguely, in the dark?”

“Not so dark, either. There’ll be a moon at ten-thirty. Anyhow, if we keep right on this course we’re bound to come within a few miles of the given bearings.”

“I guess that’s so. Well, I’m off below to watch the engines.”

“Better start the dynamo and get some ‘juice’ into the storage batteries. I mean to try the wireless again before long.”

Tom nodded, and vanished below once more. Jupe came forward from the stern, where he had been coiling lines and generally setting things to rights.

“Marse Tom,” he said, with some hesitation, “is dere any objection to informationing me concerning de percise objec’ ob dis here penguination?”

“Why, no, Jupe,” rejoined Jack, with a smile at the old negro’s remarkable choice of what he himself would have called “highfaluting” words, “the Sea King, with my father on board, as you know, is in some sort of trouble, and we are going to the rescue as fast as we can.”

“How you find out dat, Marse Jack?” asked the old man, with a tinge of suspicion in his voice.

“By wireless, Jupe.”

“What!” in a tone of frank unbelief, “yo’ all mean ter tell me dat dat birdcage rigamarole ob yo’s done tell yo’ all dat?”

“That’s right, Jupe.”

“Sho’ now! Yo’ ain’t foolin’ de ole man, Marse Jack? Dat conjo’ wire done tell yo’ all dat?”

“Of course. I should have thought that you’d seen enough of it at High Towers to know what it could do.”

“Humph!” the old negro scratched his head in a puzzled way, “yo mean dose eccentrical wabes, as yo’ call ’em, done come all de way frum Marse Chadwick’s boat to de island?”

“Just what I do, Jupe. It’s the same thing as chucking a stone in a pond. You know how the waves and ripples spread out and out in circles that get bigger and bigger?”

“Ya’as, sah.”

“Well, it’s the same thing in wireless. Instead of a pond you’ve got the air, or the atmosphere; instead of a stone, you’ve got an electric impulse from the antenna.”

“An’ when dat eccentric ’pulse go ’way from dose—dose—aunties, it jes’ spread and spread like de ripples on a pond?”

“Yes. The waves spread till they strike another wireless apparatus ‘in tune’ with them.”

“An’ yo’ birdcage fiddle was tuned to de same pitch as de Sea King’s?”

“That’s right, Jupe. You’re catching on fast We both use three hundred meter waves. That was agreed upon. Thus, you see, our station caught the message from the disabled yacht.”

“Humph! But s’pose dere was some odder station dat had its fiddle tuned de percise same way?”

“Why, then they’d have caught the message, too.”

“An’ dey’d know, too, dat de po’ Sea King done busted?”

“I suppose so,—yes. But why do you ask?”

“Fo’ jes dis reason, Marse Jack,—if any ob dem ole wreckers dat used ter hang about dese parts got dat message, maybe dey gwine ter go out dere, too.”

“I guess not, Jupe. I never heard of any such rascals who had a wireless equipment.”

“Den how ’bout dat po’ful mysterious X.Y.Z. I done heard yo’ an’ Marse Tom talkin’ ’bout at supper de odder night?”

“Oh, X.Y.Z.!” exclaimed Jack with a laugh; “well, he is a mystery for a fact. Some amateur on shore or some place, I suppose, who just happened to get tangled up with our slaves when we were practicing.”

The “X.Y.Z.” referred to had made himself manifest three days before, while Jack and Tom were conducting some experiments with their sending apparatus. In the midst of their work a confused sound had broken in upon them, and Jack, on tuning his apparatus to catch the “stranger” waves, had intercepted an apparently meaningless message signed X.Y.Z. The message consisted of a jumble of numerals which, the two lads had little difficulty in deciding, was a code of some sort. The catching of such messages being common enough in the north, they gave the matter little more thought and, in fact, till Jupe mentioned it. Jack had not recollected the occurrence at all. Now, however, as Jupe moved off forward to complete his work, he caught himself wondering who X.Y.Z. might be. He wished that they had taken down the intercepted message and devoted some of their leisure time to deciphering it; but the urgent business now in hand soon drove such thoughts out of the young navigator’s head.

Tom reappeared on deck, the inevitable bit of waste in his hands.

“I’ve adjusted the magneto,” he announced, “and I guess we’re turning over a bit faster than ordinary.”

“Good for you,” nodded Jack approvingly, “every minute counts on a job like this.”

At every turn of the shaft Jack’s heart was bounding with keen anxiety. The same might be said of Tom’s condition. The very vagueness of the message from the air, fraught as it was with the sense of disaster, added to their mystification and eagerness to reach the scene.

But mingled with all this, as the two lads stood side by side on the miniature bridge of their speedy little cruiser, was a fierce sort of pleasure as they sped through the rolling swells of the gulf, hurling white masses of foam aside from the sharp “cutwater.”

Behind them the coast line lay like a dim gray scarf stretched along the blue horizon. The keen, ozone-laden wind struck their faces with an invigorating tang. It was great, glorious, exciting to be out here on the broad bosom of the gulf, guiding a speedy motor craft toward unknown adventures. The zest of achievement, the glory of grappling with obstacles as yet unseen and hardly guessed at, ran hot in both boys’ veins. Fast as the Vagrant was, she seemed to them to crawl, and yet, thanks to Tom’s skill as an engineer, she was reeling off her thirteen knots with the regularity of a sleeping infant’s breathing.

“Jupe!” called Jack presently, “come aft and spell me at the wheel for a while. I’m going to send a few questions into the air,” he added to Tom.

“Good. We’ve got plenty of ‘juice.’ Shall I go below and send up the mast?”

“Yes. Better run it up to its full height. It won’t hurt in this light breeze, and I want all the radius I can get.”

“Right you are.”

Tom descended once more. The base of the telescoping aerial mast was in the forepart of the engine-room. A hand winch operated it much in the same manner that a fire department’s extension ladders are sent aloft. It did not take Tom long to extend the slender, yet pliant and strong steel spar heavenward to its fullest length.

At its truck, or summit, was a pulley, through which halyards attached to the aerials had been rove. Jack had gotten these out while Tom had been busy below, and in a remarkably short time the slender antenna, or aerials, were strung from mast tip to deck. There were four separate wires of stranded phosphor bronze attached to wooden spreads, and properly insulated. From them a wire led back to the instruments attached to a table in the forepart of the cabin.

The aerials being up Jack, after satisfying himself that everything was shipshape, made for the cabin. Seating himself at the wireless table he sent a signal crashing out into space.

“S-K! S-K! S-K!”

Then, after a pause:—

“L-I.”

There followed a period of listenings with the receiving switch over and the “watch-case” receivers closely clamped to the young operator’s ears. But no answer came.

A worried look crept over Jack’s countenance. This silence was ominous. Once more he manipulated the key with nimble fingers. The spark squealing and crackling shot bluely hither and thither.

But to the electrical appeals sent broadcast into the atmosphere, space vouchsafed no answer.