The two pictures were lying side by side on a little table. Suddenly an obscure noise in the room caught his attention. It was more vibration than noise, for small sounds could scarcely be heard above the whistle of the sun-ship. A slight compression of the air against his neck gave him the eery feeling that someone was standing close behind him. He wheeled and looked over his shoulder. Half ashamed of his startled gesture, he again turned to his pictures. Then a sharp cry broke from him. Athalia's picture was gone. He searched for it everywhere in the room, in his own pockets, under the furniture. It was nowhere to be found. In sudden, overpowering horror, he seized the fur coats and returned to the control room. * * * * * Dr. Mundson was changing the speed. "Look out the window!" he called to Northwood. The young man looked and started violently. Day had come, and now that the sun-ship was flying at a moderate speed, the ocean beneath was plainly visible; and its entire surface was covered with broken floes of ice and small, ragged icebergs. He seized a telescope and focused it below. A typical polar scene met his eyes: penguins strutted about on cakes of ice, a whale blowing in the icy water. "A part of the Antarctic that has never been explored," said Dr. Mundson; "and there, just showing on the horizon, is the Great Ice Barrier." His characteristic smile lighted the morose black eyes. "I am enough of the dramatist to wish you to be impressed with what I shall show you within less than an hour. Accordingly, I shall make a landing and let you feel polar ice under your feet." After less than a minute's search, Dr. Mundson found a suitable place on the ice for a landing, and, with a few deft manipulations of the controls, brought the sun-ship swooping down like an eagle on its prey. For a long moment after the scientist had stepped out on the ice, Northwood paused at the door. His feet were chained by a strange reluctance to enter this white, dead wilderness of ice. But Dr. Mundson's impatient, "Ready?" drew from him one last glance at the cozy interior of the sun-ship before he, too, went out into the frozen stillness. They left the sun-ship resting on the ice like a fallen silver moon, while they wandered to the edge of the Barrier and looked at the gray, narrow stretch of sea between the ice pack and the high cliffs of the Barrier. The sun of the commencing six-months' Antarctic day was a low, cold ball whose slanted rays struck the ice with blinding whiteness. There were constant falls of ice from the Barrier, which thundered into the ocean amid great clouds of ice smoke that lingered like wraiths around the edge. It was a scene of loneliness and waiting death. "What's that?" exclaimed the scientist suddenly. Out of the white silence shrilled a low whistle, a familiar whistle. Both men wheeled toward the sun-ship.