CHAPTER XXI.

DIRIGIBLE VS. AEROPLANE.

A galvanic shock pa.s.sed through the boy at the discovery, and he silently crawled to where Harry and Ben lay and placing his hand over their mouths he in turn awoke them.

"Don't utter a word," he whispered, "Luther Barr's air-ship is here."

From the spot in which they crouched, keeping as closely in the shadow of the stout mast as they were able, the adventurers could hear distinctly the conversation of the men in the dirigible.

"This must be the galleon," Frank heard a voice he recognized as Sanborn's saying, "it's lucky we decided to keep on."

"Well, we might as well have turned back for all the good we can do now," came another voice--that of Malvoise. "I'm not going to run a chance of wrecking the ship by making a landing in the dark."

"What, you are not going to descend?" came Sanborn's voice in a querulous tone.

"Not much," was the rejoinder. "What's the use of risking our necks and taking a chance on smashing up the air-ship. If she is damaged we would be stranded here and leave our bones in the Sarga.s.so in all probability."

"That's so," chimed in another voice--that of the inventor Constantio.

"It would be very dangerous, senor, to make a landing to-night. Let us go back to the island and start out to-morrow again."

The boys exchanged glances. So the Barr party had encamped on an island; doubtless one of the numerous little keys that abound in those waters and which, had they water on them--which few have--are ideal spots.

"That's my idea, Sanborn," went on Malvoise, "come, shall I put her about and sail back?"

"Let's circle the ship first," exclaimed Sanborn. "So far as we know we are here ahead of those Boy Aviator cubs, but we can't tell positively unless we make an examination."

Frank's heart stood still. If they circled the ship there was little doubt they would spy the Golden Eagle floating alongside; in black shadow though she was. His fingers closed on his revolver. But fortunately there was no need to use weapons then, for Sanborn's idea was overruled, and from the position in which the air-ship hovered she could not spy the aeroplane.

"No; come on, let's get back," urged Malvoise; "there is something wrong with one of the cylinders and I want to fix it before we tackle the job of taking off the treasure."

"Very well then," said Sanborn, yielding to the will of the majority.

"We'll get back, but I want to be here first thing in the morning and make a thorough overhauling of the ship. There ought to be enough gold aboard her, from what I overheard Bluewater Bill say, to make us all kings."

"Ah, then I can invent more dirigibles, large ones to carry pa.s.sengers across the Atlantic," the boys heard Constantio say--though of course, till Ben told them, they were not aware of the speaker's ident.i.ty.

To their great relief the engine of the dirigible, which had hovered stationary above the galleon during the men's talk, was once more set in motion and the big air-ship drove off at a rapid pace.

"Phew! that was a narrow escape," exclaimed Frank. "I don't want many more like that, I can tell you."

"If they had only gone round the galleon they could not have escaped spying the Golden Eagle," said Harry.

"Fortunate for them they didn't," said Ben grimly, fondling his blue magazine revolver; "they'd have got some indigestible leaden pills, I'm thinking."

"Shooting is just what we want to avoid," said Frank. "I never want to have to fire on a human being."

"Well, if they fire at you first, what are you going to do?" was Ben's incontrovertible argument.

Naturally the Boy Aviators and their companion slept no more that night. The remaining hours before daybreak were occupied with getting everything in first-cla.s.s shape aboard the Golden Eagle in readiness for what might prove a dash for life.

"Are we faster than the dirigible?" asked Harry, who realized as well as his brother that there might be a chase between the two air-ships.

"I don't know," was Frank's reply, "we ought to be; but from Ben's description, and what we saw of her, that dirigible must be at least a hundred and fifty feet long and she has a more powerful engine than we have."

"But look at her weight," argued Harry.

"That doesn't cut so much figure if you have a powerful enough engine to overcome it," was the reply; "some European dirigibles, bigger than Luther Barr's, have made eighty and even ninety miles."

"Well, we wouldn't stand much chance with an affair like that and that's a fact," commented Harry.

"We can only hope things won't come to such a pa.s.s," said Frank.

Soon all was ready for a start and Frank, taking careful bearings, headed the Golden Eagle round on the course she had followed on her way to the galleon. As the sun poked his rim above the horizon the Golden Eagle shot into the air and rapidly the hulls of the galleon and Bluewater Bill's castaway hulk were mere specks behind them.

The spirits of the boys rose. They breakfasted on cold stuff cooked before they started and coffee heated over the exhaust of the engine.

Ben lit his pipe, and with Frank at the wheel and Harry on lookout, any one looking at the party in the Golden Eagle would have said that they were a trio of pleasure-makers instead of adventurers engaged on a daring dash for fortune.

It was about nine o'clock in the morning when the danger they had feared loomed up out of the clear sky as suddenly as a tropic squall.

Coming straight toward them, but a mere dot on the sky, though momentarily growing larger, was an air-ship that they could not doubt was Luther Barr's.

"What are you going to do?" asked Harry, as Frank put the wheel over and brought the aeroplane on a course which would take her far to the westward of the dirigible.

"Try to avoid her," was Frank's reply; "they are equipped with a rapid-firing gun and could make mince-meat of us in a short time."

"We have rifles," said Harry.

"They would be little use against such a weapon," replied Frank.

But as the Golden Eagle shifted her course it became clear to those aboard her that the other air-ship did the same.

"They have seen us," gasped Harry.

"Yes, and mean to pursue us, too," was Frank's reply, through gritted teeth; "well, we'll give them a long chase of it."

The Golden Eagle was speeded up to her full capacity, although with the heavy load she was carrying, she by no means attained the speed of which she was capable.

In one thing, however, she had the advantage over the dirigible. She could maneuver with twice the speed and turn and twist like a snake, while the more c.u.mbersome air-ship took a lot of handling to navigate in any intricate movements.

As the dirigible drew nearer, the boys, critical as was the moment, could hardly restrain their admiration at the fine appearance she presented. Her distended gas-bag shone in the sunlight like silk and her cabin woodwork sparkled where bra.s.s handholds and plates were attached to it, like the main deck of a pa.s.senger liner.

Suddenly, however, her sinister character became apparent.

There was a puff of smoke from what, if she had been a "sea" ship, would have been her bow, and a projectile sang by the Golden Eagle.

"That was a warning shot, Frank," cried Ben; "the next will come closer."

"I am going to watch them get ready to fire and then drop suddenly,"

said Frank, his face white, but with a set, determined look on it.