"We can't see the surface of the thing at all, Lucian," said Eyer. "I'll simply have to feel for it." "Well, you've done that before, too. We can manage all right." Down they dropped. The updraft was now a cushion directly under them. And then their wheels struck something solid. The plane moved forward a few feet--with a strange sickening motion. It was as though the surface of this substance were globular. First one wheel rose, then dipped as the other rose. The plane came to rest on fairly even keel, and the partners, while the motor idled, stared at each other. "Well?" said Eyer, a trace of a grin on his face. "If it'll hold the plane it will hold us. Let's slide into our stratosphere suits and climb out. We have to get close to this thing to see what it is." "Parachutes?" said Eyer. Jeter nodded. "It would simplify matters if the thing happened to tilt over and spill us off, I think," said Jeter, matching Eyer's grin with one of his own. "I can't think with any degree of equanimity of plunging ninety thousand feet without a parachute." "I'm not sure I'd care for it with one," said Eyer. * * * * * They were soon in the tight-fitting suits which were customarily used by fliers who climbed above the air levels at which it was impossible for a human being to breathe without a supply of oxygen in a container. Their suits were sealed against cold. Set in their backs were oxygen tanks capable of holding enough oxygen for several hours. Over all this they fastened their parachutes. Then, using a series of doors in order to conserve the warmth and oxygen inside their cabin, they let themselves out, closing each successive door behind them, until at last they faced the last door--and the grim unknown. They glanced at each other briefly, and Jeter's hand went forth to grasp the mechanism of the last door. Eyer stood at his side. Their eyes met. The door swung open. They stepped down. The surface of this stratosphere substance was slippery smooth. Now that they stood on its surface they could sense something of its profile. Movement in any direction suggested walking on a huge ball. The queer thing was that they could feel but could not see. It was like walking on air. Their plane appeared to be suspended in midair. For a moment Jeter had an overpowering desire to grab Eyer, jerk him back to the plane, and take off at top speed. But they couldn't do that, not when the world depended upon them. Had Kress encountered this thing? Perhaps. How must he have felt? He had been alone. These two were moral support for each other. But both were acutely remembering how Kress had come back. And his plane? They'd perhaps discover what had happened to that too.