CHAPTER XXIV.
THE INVENTOR'S TREACHERY.
Weak almost as a baby, Frank made his way to the stern of the navigating deck, and with what seemed the last ounce of strength in his body he gave the cord a feeble yank.
It resisted and the boy tugged once more.
Still it stuck.
Mustering his strength to keep on his feet a minute longer, the boy tied the cord to his wrist. Then, as he fell forward in the swoon that he knew must ensue, the cord tightened under the weight of his body and yielded.
The dirigible with an unconscious crew aboard plunged on through the night, but every moment exhausted more gas from her bags and the craft gradually dropped till she had reached an altitude where the air was breathable.
Frank was the first to stir. He discovered at once that the air-ship's drop must have been considerable and hastened to close the valve which connected by a tube with each one of the gas partitions. The dirigible's fall was checked in this way and the lad made his way forward.
By this time a sickly dawn had arisen and although it was still blowing hard the full fury of the hurricane had distinctly moderated. The dirigible, however, was clearly beyond all control and Frank, after a glance into the engine-room, where the engineer lay insensible beside his machines, started for the pilot-house.
At its threshold he stopped with a cry of surprise.
The railing, against which he had left Malvoise lying, gaped open raggedly for a space of several feet, as if a heavy body had plunged through it. A brief examination showed the boy some bits of cloth still clinging to the rough ends of the shattered rail, indicating plainly enough that the doomed Frenchman had been hurled into empty space while the storm was at its height and they all lay senseless.
Undoubtedly his body had been rolled by a lurch of the ship in toward the cabin and then been cast outward again by a reverse swing. The railing, none too strong at best, had evidently not been capable of withstanding the impact and the Frenchman's body had been hurled through into the void.
Shuddering at the thought of such an end, Frank aroused his brother and Ben and then went aft to inspect the engine-room. He found that of the eight cylinders only five were doing their work, and a brief examination showed why. The insulation on three of the spark plugs had cracked and it was not before he had done a lot of rummaging around that the boy found spare ones stored in a locker.
By this time the engineer, who seemed a decent enough fellow, and told Frank his name was Dick Richards, had recovered and helped the boy fit the new sparkers to the motor. First, however, Frank had hailed Harry through the tube leading to the pilot-house.
"How high are we?" he asked.
"A thousand feet," came back the reply.
"All right," shouted Frank back. "I guess the wind has moderated enough now for us to drift for a while. I am going to stop the engine."
The machinery accordingly was brought to a standstill and Frank and the engineer set busily to work placing the new sparkplugs and wiring them up.
This completed, Frank hailed Harry once more.
"I'm going to start up."
"All right. I'm looking out," came the reply.
The compressed air apparatus that started the engines was put in operation and the engine was soon working as if nothing had happened.
"Say, you are an all right mechanic," was Dick Richards' admiring tribute to Frank's skill.
By noon the last traces of the hurricane had died out and the dirigible was driving forward over a sparkling sea with a cloudless sky overhead. After breakfast, in which the now resuscitated members of the crew and Constantio took part, Frank called them forward and told them of the fate of Malvoise. None of them seemed particularly grieved, as the man had undoubtedly been a hard taskmaster.
"You are captain of this ship now," said Constantio to Frank. "I am only her inventor and have already received from Luther Barr the full purchase price. I have deposited it in a bank in New York. In this treasure they are hunting I have no interest. All I want to do is to invent air-ships."
Constantio had recognized Ben Stubbs as soon as he set eyes on him, and laughed with apparent good nature at the recollection of their meeting in Boston. He had recovered the watch the little gamin got away with, he told them, and had never mentioned to Luther Barr the fact that Ben had inspected the air-ship and then escaped, for fear of the grim old millionaire's wrath.
"When he is mad he is like one volcano," he declared volubly.
Breakfast over, they skimmed along through the air till noon, when
Frank took an observation with the ill-fated Malvoise's instruments.
"We ought to be falling in soon with one of the Bahama group of islands," he announced. "We were not driven so far as I thought, and if we can make a landing we ought to be able to effect repairs and then fly for land. We certainly cannot go much further on the supply of gas we now have, the ship is getting lower all the time."
This was indeed the fact. With her heavy load and reduced supply of gas the air-ship was rapidly decreasing the space between herself and the sea.
During the afternoon the water tanks were emptied, which lightened the ship considerably, but left the voyagers only a small supply of the fluid, which was likely to prove serious if they did not find land soon. By supper time it became necessary also to tear out some of the heavy cabin fittings and cast them away.
By early the next day, after a restless night, the ship had settled so much, despite the lightening process, that she rode soggily along at not more than fifty feet above the level of the sea. The situation was indeed a serious one.
Suddenly there came a hail from Ben, who was standing at the bow of the craft.
"Land ho!"
The adventurers crowded forward.
There, sure enough, dead ahead of them, was what looked like a tiny blue cloud on the horizon, but which Ben's practiced eye had told him was land. With new heart the voyagers drove on and by mid-afternoon were in sight of the island, which on closer view proved to be one of those small palm-crowned atolls that are common enough in these waters.
The dirigible had by this time settled so badly that she was barely twenty feet above the wave-tops.
Some sacks of ballast still remained, kept by Frank for an emergency. He now was compelled reluctantly to give the order to cut these away and one by one they dropped overboard; but as they did so, the ship rose and an hour later they landed on a smooth beach.
The island did not seem to be of great extent, but to the delight of the adventurers, from the midst of the cocoanut grove that crowned the islet there flowed a tiny stream of clear water. This was indeed a godsend, as they did not know how long they might have to remain there. With a spade, which formed part of the dirigible's outfit—"I suppose they figured on shoveling out the treasure," laughed Harry—a small basin was soon dug out for the water to settle in and make a sort of small well, from which it could be dipped out for cooking and drinking purposes.
Fortunately the larder of the dirigible was well stocked, and as they were two mouths short they were not in any immediate fear of hunger. That evening, when arrangements for sleeping and keeping watch for any passing steamer or vessel had been made, Constantio beckoned to Frank and asked him to join him in a walk along the beach. The lad, nothing loath of a chance for exploration, started off with the Spanish inventor, who seemed to be anxious to confide something to him.
"You are worried about getting away from the island?" he said.
"I am—yes," rejoined Frank, "you see our gas is exhausted and I for one can't figure out but we shall stay here till some one comes along and picks us up. Unless we can build a raft out of the remains of the dirigible."
"Oh, make yourself easy about that, my dear young friend," exclaimed the inventor. "I can refill the gas-bag and that without delay, but—but—well, to be frank with you, how much is it worth to you if I do so?"
Frank was amazed at the sudden proposal and no less astonished at the
Spaniard's boast that he could inflate the dirigible.
"What do you mean?" he asked. "I confess I don't altogether understand you."
"I thought I had made myself clear," was the reply. "I have changed my mind since I spoke to you last about the treasure, and now I feel that I am entitled to some of it if I can refill the dirigible."
"Why, yes," said Frank, with a laugh; "of course you are IF you really can."
"Would five thousand dollars' worth of ornaments or doubloons seem too much?" ventured the Spaniard.
Frank broke into a loud laugh.
"Why, no; you shall have that, and gladly, if you think you can help us to get out of this place."
"Thank you," said the inventor, quite seriously, "I don't want more than my just dues, but I certainly am entitled to that."
"Oh, certainly," laughed Frank, much amused at the man's deprecatory manner. "What is your plan?"
"Well, senor," said the Spaniard, "I have a certain amount of my gas-producing powder left in my cabin. There is none too much, but enough, I think, to inflate the dirigible with—at any rate, to fit her for flight to the mainland, which cannot be so very far off."
Frank nodded.
"There are some empty cylinders on board," went on the inventor. "All that is necessary to do is to put equal parts of sand, water and my powder into the cylinders and then screw on the caps to produce almost pure hydrogen gas at tremendous pressure. You follow me?"
"Yes," said Frank, "when can we do this?"
"Why, to-morrow morning," was the reply. "The actual inflation will take but little time."
As they returned to their camp they found it in a state of great excitement. Two of the men, in strolling about the island, had found lying up in a small cove, where it seemed to have drifted, a ship's boat.
There was no clue as to how it had come there, but on its stern were painted the words "Falcon, New York."
"I'll bet a lemon that it's one of the ship's boats of the Falcon that I read about been missing this year," exclaimed Ben; "it's got oars in it, too, they say. They are lashed under the seats, so that it must have broken loose from the ship when she went down and been washed ashore here. We can get away in the boat if nothing better offers."
Frank drew him aside and explained to him Constantio's plan for reinflating the gas-bag.
"We will try that, and if that plan fails then we can take to the boat," said the boy.
Ben agreed that if the air-ship could be inflated it would be much better to fly to land in her than to set out under the tropical sun in an open boat, not knowing where they might land.
The camp was so arranged that night that the treasure was placed near to the boys and Ben, while the three members of the dirigible's crew, her engineer and Constantio slept at some little distance.
Had the boys seen the gleam that had come into the inventor's eyes at the discovery of the boat they would not have been so trustful of him when he volunteered to take the middle watch of the night. As it was, however, they little imagined the plot that had formed in the fellow's head. While the boys and Ben slumbered, however, he drew aside the engineer and Wells, the red-headed sailor, and the three rapidly stocked up the boat with water from the spring in kegs and jars taken from the dirigible and laid in a supply of provisions. Then they awakened the other two men and explained to them in low whispers the plan to escape from the island they had formed.
"We will get all the treasure and divide it," whispered the cunning inventor. "If the boys wake while we are getting it to the boat, don't hesitate to attack them. We are stronger in numbers and can beat them off."
The other two readily agreed, more particularly as the inventor told them that it was the boys' intention to keep all the treasure for themselves in the event of their getting ashore in the dirigible. Before the boat had been found the inventor had been willing enough to aid the boys, but with the discovery of that means of escape his plans had undergone a change. He saw a way to appropriate the entire mass of treasure.