Chapter XVI: Off on the "air Route."

In the meantime indignation was at white heat on Brig Island. Mr. Sterrett was for advertising the disappearance of Duval, and offering a reward for his apprehension. He confessed that he had not liked the man's looks, but had shipped him as help was hard to get at the time. Dr. Perkins agreed that it might not be a bad idea to communicate at once with the authorities and try to have the rascal captured.

"But," he added, "I am afraid he is too clever a scamp to fall into the clutches of the law very easily."

"I am of that opinion, too," frankly admitted Mr. Sterrett, "but it will do no harm to do all we can to place him where he belongs."

To get ashore Frank had first to swim off to the motor boat, for the skiff, as we know, had vanished. He then ran the engine-driven craft in alongside some rocks that sloped down into deep water, and from that elevation the party embarked. A quick run was made to Motthaven, from whence a description of Duval was wired to the metropolitan police, and the local authorities urged out of their usual lethargy by promises of a reward if Duval was found. Late that afternoon the search yielded results in the finding of the abandoned skiff, and the discovery of the hut in which the Daniels had been living since the boys had instituted proceedings against them.

Some evidences of a hasty departure were found, but no clews that would give any idea of whither the fugitives had proceeded. In fact it was only by piecing together some scraps of torn paper that it was discovered that the hut had been used by the Daniels as a refuge.

"Well," said Dr. Perkins that evening, after they had bidden good-by to Mr. Sterrett and his friend, who had returned to New York, "well, in my opinion the less time we lose in getting to Black Bayou the better it will be, for, to my mind, there is little doubt that Duval means to forestall our friend, Ben Stubbs, in ransacking the wreck."

The others agreed that this seemed highly probable, and Dr. Perkins made immediate arrangements for a caretaker to occupy quarters on Brig Island during their absence. This done, a return was made to the little settlement, and the next day final preparations were made for the adventurous trip through the air. The _Sea Eagle_ was provisioned, and a light wireless apparatus installed, the stay wires being used as aerials. Of course the instruments were not so strong as those used at the shore station, but it was calculated that they had a capacity of about twenty miles over land, and forty above the sea, depending, of course, a good deal on the wave adjustment and the weather conditions.

Twenty-four hours after the adventurers had started work on the _Sea Eagle_, the craft was ready for her dash. Ben Stubbs, Pudge Perkins and Billy Barnes were to go to New Orleans, there to await the arrival of the party. Their departure took place amid regretful wails from Pudge, who loudly declaimed:

"Aerials and ant-hills! I don't see why we can't go by the _Sea Eagle_."

But Dr. Perkins' word was law and he had decided that the fewer persons who took part in the test the better the chance of success would be, and as Frank and Harry were both experienced aviators he placed great reliance in their aid. The morning after the departure of the New Orleans-bound passengers the caretaker and his family arrived. They were honest folk from the shore, who could be trusted to look after the many valuable devices on the island, and keep curiosity seekers off till the party returned. For Dr. Perkins had decided to use Brig Island as a permanent workshop, and expected, if the _Sea Eagle_ proved a success, to build many craft like her and dispose of them at good prices. The working of the electric fence was explained to the caretaker; but he declared:

"I reckon my old gun will do more to keep undesirables off than any of them electric didoes."

There was now nothing more to do, the caretaker being duly installed, but to take to the air, in what was, at that date, the most unique aerial craft in existence. For the voyage, beside the provisions and extra fuel and oil, life belts had been provided, and not a detail had been overlooked. It was seven o'clock on a fine, breathless morning when Dr. Perkins gave the order, "Start up the engines!"

A thrill shot through both Frank and Harry at the words. Experienced in aerial adventure as were both boys, they could not but feel that they were embarking on the most adventurous undertaking of their lives.

"We're off!" cried Harry, as a quiver ran through the craft, and the motor roared from its exhausts, emitting clouds of mingled flame and blue smoke.

"Yes; off on a fight for fame and fortune!" cried Frank, as Dr. Perkins threw in the clutch; and, with her propellers beating the air so rapidly that they were a mere blur, the _Sea Eagle_ shot skyward.

In half an hour's time, to the watchers on the island, the aerial craft had dwindled to a mere dot in the distant sky, and five minutes later she vanished from view. The boys gave many backward looks as they winged away from Brig Island. Despite their adventures, they had spent many pleasant days there, and it appeared to them to be almost a second home. Of all that they were to experience before returning to the island they little dreamed at the moment, but their hearts beat high with exultation as the _Sea Eagle_ winged her way southward at forty miles an hour, and about five hundred feet above the ocean.

They had been in the air about an hour when they encountered a situation which may become common enough before many years have passed, but which was an exciting novelty to them. Off on the horizon a liner was sighted, steaming toward the American coast. Before long they made her out to be a big, two-funneled craft, painted black, and with numerous decks rising above her shapely hull.

"One of the transatlantic liners that make Portland their terminal," decided Dr. Perkins.

"Shall I wireless them?" said Harry.

"Yes, do so. It will be an interesting experiment, and besides will show how the apparatus will work."

Harry lost no time in getting to work. After a brief interval he "raised" the operator on the liner, Dr. Perkins keeping the _Sea Eagle_ swinging in big, lazy circles while he did so.

"We sighted you from the bridge half an hour ago," flashed the operator, "who and what are you?"

"The hydro-aeroplane _Sea Eagle_, bound from Maine for New Orleans. Who are you?" flashed back Harry.

"The _Ultonia_, of the Portland and Liverpool line, eight days out from England," was the rejoinder; "have you got any American newspapers on board?"

Now it happened that Dr. Perkins had brought some papers of the day before along in his pockets, and at Harry's request he handed them to him.

"What are you going to do?" asked Frank.

"I was going to suggest that we dive across the _Ultonia_ and deliver the papers," said Harry; "can we do it, doctor?"

"By all means," rejoined Dr. Perkins, deeply interested; "flash them a message of what we intend to do so that they may be prepared."

Harry sent out the message and the operator flashed back a quick "Thanks," adding the next moment: "Good-by. I'm going to beat it out on deck and watch you."

Frank, in the meantime, had done the papers up in a compact bundle and weighted them with an empty beef can.

"All ready?" cried Dr. Perkins.

"All ready, sir," was the prompt reply from the boys.

"Then hold tight. I'm going to make a swift dive."

The liner was now almost directly underneath the soaring _Sea Eagle_. Her rails were black with passengers craning their necks upward at the great, man-made bird. From her funnels poured clouds of inky smoke, while her sharp prow cut the water on each side of her bow into sparkling foam. On the bridge were uniformed officers, pointing binoculars and spy glasses aloft, for the operator had communicated the news of what the _Sea Eagle_ was about to do.

Suddenly the watching throngs of ocean travelers saw the _Sea Eagle_ poise in air like a hawk about to pounce. Then down she came, cleaving the air like a falling stone.

A great cry went up from the packed decks. It seemed as if the air craft must perish, that nothing could check her fall, and that she was doomed to plunge headlong into the sea. But in a flash the cry changed to a mighty cheer.

Less than forty feet from the water the _Sea Eagle_ was seen to shoot upward and straight toward the steamer. Like an arrow from a bow the great aerial craft shot whizzing above the liner's bridge, and under the wireless aerials extending from mast to mast. Just as she roared by above the officers' heads, like some antedeluvian thunder-lizard, something was seen to fall downward and land on the top of the charthouse. It was the bundle of papers thrown by Harry. A sailor scrambled up and got them, while the crowded decks yelled themselves hoarse.

Then the _Sea Eagle_ soared up high above the mast tips, and Harry seated himself at the wireless once more. Presently to his ears came a message from the speeding liner far below.

"Captain Seabury wishes to congratulate you on the most wonderful feat of the century."