"Some of these men were good mechanics when the navy was here," said Sanchez. "Wait." He turned and spoke to someone in the dome. One of the men of Rathole came to Jan's side and tried the engines. They refused to catch. The man made carburetor adjustments and tried again. No success. He sniffed, took the cap from the fuel tank and stuck a finger inside. He withdrew it, wet and oily, and examined it. He turned and spoke to Sanchez. "He says that your groundcar must have a diesel engine," Sanchez interpreted to Jan. "Is that correct?" "Why, yes, that's true." "He says the fuel will not work then, _senor_. He says it is low-grade fuel and the platform must have high octane gasoline." Jan threw up his hands and went back into the dome. "I should have known that," he said unhappily. "I would have known if I had thought of it." "What is to be done, then?" asked Sanchez. "There's nothing that can be done," answered Jan. "They may as well put the fuel back in my groundcar." Sanchez called orders to the men at the platform. While they worked, Jan stared out at the furiously spinning windmills that dotted Rathole. "There's nothing that can be done," he repeated. "We can't make the trip overland because of the chasm out there in Den Hoorn, and we can't fly the platform because we have no power for it." Windmills. Again Jan could imagine the flat land around them as his native Holland, with the Zuider Zee sparkling to the west where here the desert stretched under darkling clouds. * * * * * Jan looked at his watch. A little more than two hours before the G-boat's blastoff time, and it couldn't wait for them. It was nearly eight hours since he had left Oostpoort, and the afternoon was getting noticeably darker. Jan was sorry. He had done his best, but Venus had beaten him. He looked around for Diego. The boy was not in the dome. He was outside, crouched in the lee of the dome, playing with some sticks. Diego must know of his ailment, and why he had to go to Oostpoort. If Jan was any judge of character, Sanchez would have told him that. Whether Diego knew it was a life-or-death matter for him to be aboard the _Vanderdecken_ when it blasted off for Earth, Jan did not know. But the boy was around eight years old and he was bright, and he must realize the seriousness involved in a decision to send him all the way to Earth.