Jerry carefully guided the jeep along the dangerous cliff. If one of his wheels should slip over the side, it would be a fall to frightful death a hundred feet straight down. At last even this peril was past, and Jerry drove up a gradual incline over bare rock to a bluff that overlooked the distant land for many miles.

“The camp!” he said joyfully. “That’s it below—only a few miles away!”

He followed a curve that swept onto the plain below. When he was on a level again, it seemed that all his troubles were over. He felt better by the moment as he drove closer and closer to his destination.

Then, without warning, his wheels began to bog down in a pumice mire. His heart did a flip-flop and he checked the map. He saw a warning to drivers to avoid this spot. In his overconfidence, he had blundered right into it!

He gave the little jeep full power. It jerked crazily through the clinging stuff. Over to the right the pumice seemed to thin out, and farther over he could see the roadway he should have taken. He swung his wheels to the right and the jeep lurched through the gray sand, using up a lot of power, but making little progress. For minutes on end Jerry gave the jeep all it had, and he could hear its engine laboring tiredly.

Suddenly the motor died. Jerry tried to start it again but could not. He checked his temperature gauge. The engine was extremely hot from the continual use of top power. From his mechanical school course, Jerry realized the rotors had “frozen” and that it wouldn’t run again until they had cooled off.

As he waited impatiently for the engine to cool, a warning voice in his mind was saying: “Your oxygen is getting lower by the second. If the jeep doesn’t get out of here within the next fifteen minutes, you and your dad will never make it.”

Jerry shook off the terrible thoughts. He stamped his feet to warm them. The electric circuit in his suit seemed to be breaking down. If it collapsed completely, he would be frozen instantly by the Lunar cold.

Jerry massaged his dad’s hands and legs in case his suit, too, was getting colder. He worked steadily until his hands ached. Then he checked the gauge again. It was falling slowly, but heavy insulation was still keeping the engine hot.

At last Jerry decided he should not wait any longer. With a prayer on his lips, he pressed the starter button. The engine rumbled sluggishly, coughed, then quickened to full strength. He jammed the fuel pedal hard and tried to guide the jeep’s swirling, spinning motion through the Lunar sand. Slowly the little car pulled itself like a weary swimmer toward the firm bank. Finally the wheels found good traction and the jeep lurched onto the roadway.