Linton again left the helm in Renshaw's hands. It was useless to retain it. He scrambled forward to assist Wilton in his desperate efforts to right the machinery. A dreadful feeling of sickness began to overpower him as the air-ship swayed and waltzed in the upper air-currents, lurching and righting as if struck by successive waves, but ever mounting higher and yet higher. It grew intensely cold. Feathery flakes of snow began to envelop them. Their lungs laboured. It became more and more difficult to breathe. Linton gasped enquiries which either Wilton did not hear or could not answer. He glanced back at their ill-starred passenger, who had set out to recover power and a great position and now was rushing to an awful death. He saw that Renshaw's head rolled limply on his shoulders. Already he seemed to be insensible. Filled with terror and alarm, he shouted to Wilton though the man was close to hand, but his voice, though the effort of utterance was so great, sounded even to himself quite faint and far away. By the light of the protected spirit lamp fixed to the tiny engine house, Linton saw that the recording instrument already registered an altitude of 20,000 feet. A dull indifference began to take possession of his mind. His faculties were slowly freezing. Even his eyesight now began to fail. He could scarcely see the column of mercury in the glass, or the minute hand of his watch. He felt that consciousness would soon completely desert him. His right hand was resting on the gunwale of the boat; he found he could not raise it. He could scarcely move his lower limbs, and, turning once more to glance at the barometer, his head fell forward helplessly. By a violent exercise of his muscles and his will, he raised his face a little, but for an instant only. It drooped again. He slid down into the bottom of the boat. His fading gaze sought that of Wilton. They looked into each other's eyes, like dying men bidding one another silent, sad farewells. The mists of death already seemed to be closing on them, when a sudden variation of the temperature, or, it may be, some magnetic current partially revived them. But the _Bladud_ still rushed upward, ever upward. They had reached a height of four miles above the earth, and the temperature had fallen to 24° below freezing point of water. To this appalling altitude the _Bladud_ had ascended with almost incredible rapidity. Upward, and upward still, they went, until five miles, then six, was reached above the surface of the vanished earth. Out of the void a muffled voice reached Linton's ears, the welcome voice of a living fellow-creature. It was Wilton trying to rouse him, Wilton speaking with urgency and vehemence. Gradually he came out of his swoon; familiar objects close to him revealed themselves again. Wilton was lying in the bottom of the boat. He was striving in vain to reach Linton. The piercing cold had almost paralyzed him. His hands were freezing.