There was a noise on the "Albatross." Evidently, the alarm had been given. The escape was discovered.

"Help! Help!" shouted somebody. It was the look-out man, who had got rid of his gag. Hurried footsteps were heard on deck. Almost immediately the electric lamps shot beams over a large circle.

"There they are! There they are!" shouted Tom Turner. The fugitives were seen.

At the same instant an order was given by Robur, and the suspensory screws being slowed, the cable was hauled in on board, and the "Albatross" sank towards the ground.

At this moment the voice of Phil Evans was heard shouting, "Engineer Robur, will you give us your word of honor to leave us free on this island?"

"Never!" said Robur. And the reply was followed by the report of a gun, and the bullet grazed Phil's shoulder.

"Ah! The brutes!" said Uncle Prudent. Knife in hand, he rushed towards the rocks where the anchor had fixed itself. The aeronef was not more than fifty feet from the ground.

In a few seconds the cable was cut, and the breeze, which had increased considerably, striking the "Albatross" on the quarter, carried her out over the sea.

Chapter XX

THE WRECK OF THE ALBATROSS

It was then twenty minutes after midnight. Five or six shots had been fired from the aeronef. Uncle Prudent and Frycollin, supporting Phil Evans, had taken shelter among the rocks. They had not been hit. For the moment there was nothing to fear.

As the "Albatross" drifted off from Pitt Island she rose obliquely to nearly three thousand feet. It was necessary to increase the ascensional power to prevent her falling into the sea.

When the look-out man had got clear of his gag and shouted, Robur and Tom Turner had rushed up to him and torn off his bandage. The mate had then run back to the stern cabin. It was empty! Tapage had searched Frycollin's cabin, and that also was empty.

When he saw that the prisoners had escaped, Robur was seized with a paroxysm of anger. The escape meant the revelation of his secret to the world. He had not been much concerned at the document thrown overboard while they were crossing Europe, for there were so many chances that it would be lost in its fall; but now!

As he grew calm, "They have escaped," said he. "Be it so! But they cannot get away from Pitt Island, and in a day or so I will go back! I will recapture them! And then --"

In fact, the safety of the three fugitives was by no means assured. The "Albatross" would be repaired, and return well in hand. Before the day was out they might again be in the power of the engineer.

Before the day was out! But in two hours the "Albatross" would be annihilated! The dynamite cartridge was like a torpedo fastened to her hull, and would accomplish her destruction in mid-air. The breeze freshened, and the aeronef was carried to the northeast. Although her speed was but moderate, she would be out of sight of the Chatham Islands before sunrise. To return against the wind she must have her propellers going, particularly the one in the bow.

"Tom," said the engineer, "Turn the lights full on."

"Yes, Sir."

"And all hands to work."

"Yes, Sir."

There was no longer any idea of putting off the work till tomorrow. There was now no thought of fatigue. Not one of the men of the "Albatross" failed to share in the feelings of his chief. Not one but was ready to do anything to recapture the fugitives!

As soon as the screw was in place they would return to the island and drop another anchor, and give chase to the fugitives. Then only would they begin repairing the stern-screw; and then the aeronef could resume her voyage across the Pacific to X Island.

It was important, above all things, that the "Albatross" should not be carried too far to the northeast, but unfortunately the breeze grew stronger, and she could not head against it, or even remain stationary. Deprived of her propellers she was an unguidable balloon. The fugitives on the shore knew that she would have disappeared before the explosion blew her to pieces.