Above the gentle hum of the engine Dick could hear a gurgling, splashing sound, and looking downward discovered that a spray of water was falling from the airship, a spray which was caught by the breeze, whirled to one side, and transformed instantly into thin flakes of ice which went swimming through space to find a resting-place on the slopes of the mountain. "Throwing out ballast," Joe explained. "Now we're moving." The ship was clambering upward at a rapid pace, thanks to the weight rapidly streaming from her tanks. Joe watched his barometer now with smiling eyes. "Thirty thousand feet," he stated solemnly. "Thirty-five thousand feet, gentlemen. Almost a world's record. But five more feet and I shall be satisfied." Had it not been for the mouthpieces which all were now compelled to keep constantly in use the crew would have cheered him. As it was they tramped the gallery, swinging their arms, beating their fingers, and muffling their faces in the first article of clothing upon which they could come. The cold was too intense for words, in spite of the heating arrangements aboard the ship. Indeed, but for active movement many of the crew would not have been able to bear it. And steadily, relentlessly, the ship ascended, while Dick, at Joe's bidding, emptied first one and then the remaining tanks aboard the vessel. It was with a shout of triumph that Joe announced that they had ascended to forty thousand feet. "Kindly observe the barometer," he called. "Kindly bear evidence to the fact that we have gained this record." Then began the descent. Joe arrested the elevating motors, and at once the ship began to fall. Not rapidly, as one might have expected, but slowly, imperceptibly, so smoothly that but for the barometer none would have known that she was moving. And now, as they reached the level of thirty thousand feet, and that tiny Union Jack came into view once more, but a stone's throw to their right, the mercury ceased to move. In spite of accelerating his motors Joe could no longer force the ship to descend. "Dropped all the weight out of her," he said cheerfully. "Must now let gas escape. That's merely a question of operating the escape valves. See, they're all linked up to this lever." He leaned over the engine, gripped a long handle and pulled upon it. It refused to move. It was firmly jammed, or rather, the linked mechanism beyond it was firmly frozen. "Annoying," he exclaimed, though Dick could have sworn that an anxious expression crossed his face. "Try again."