“O.K., Dad,” he said, “we’ll be expecting your wire.” He said good-bye and hung up. “Sorry to be on the phone so long,” he said to Mr. Yee. He reached for the slip.

“An elderly person should not make the trip here,” Mr. Yee said in his placid, implacable voice.

“He’s made up his mind to see how we’re doing,” Jack said.

“And if you are not doing as well as he would wish, can he help you?” Mr. Yee smiled with contempt. “Are you supposed to have struck it rich? Tell him there are no diamonds. The UN got them. As to the call which I gave you: that refrigeration unit, according to the file, was worked on by us two months ago for the same complaint. It is in the power source or conduit. At unpredictable times the motor slows until the safety switch cuts it off to keep it from burning out.”

“I’ll see what else they have drawing power from their generator,” Jack said.

It was hard, working for Mr. Yee, he thought as he went upstairs to the roof where the company’s copters were parked. Everything was conducted on a rational basis. Mr. Yee looked and acted like something put together to calcu late. Six years ago, at the age of twenty-two, he had calculated that he could operate a more profitable business on Mars than on Earth. There was a crying need on Mars for service maintenance on all sorts of machinery, on anything with moving parts, since the cost of shipping new units from Earth was so great. An old toaster, thoughtlessly scrapped on Earth, would have to be kept working on Mars. Mr. Yee had liked the idea of salvaging. He did not approve of waste, having been reared in the frugal, puritanical atmosphere of People’s China. And being an electrical engineer in Honan Province, he possessed training. So in a very calm and methodical way he had come to a decision which for most people meant a catastrophic emotional wrenching; he had made arrangements to emigrate from Earth, exactly as he would have gone about visiting a dentist for a set of stainless steel dentures.