Dayton's immediate superior, Dr. L'Hai of Evolutionary-Biogenetics, had voiced the half-felt sentiment, as the two of them, so long ago, had watched the young children crawling in their elaborately constructed play-pen of glass. The dial on the outside showed that the infants were receiving only a small percentage less oxygen than was normally found on Earth. The dial also pointed to a temperature of 58°, comfortable but cool for such young children.

"Look at them," L'Hai said proudly. "They hardly know the difference. In three months—" with a gesture toward the dials—"a bit lower temperature, a bit thinner air. Slowly they will develop until they will be completely free of our prison. And they will build Mars!"

Dayton gazed around him at the flat countryside and the time-eroded mountains some five hundred miles distant, looming so clearly in the thin air they seemed barely fifty feet away.

For acre upon acre, the flatland was unbroken, save by scrubs of a dingy greenish-blue hue and the ever-present crawling, red-tinged lichen. Not far from where the two scientists stood, there were three large plexi-glass bubbles, filled with oxygen: greenhouses containing vegetables, fruit, and stored protein foods.

But what drew Dayton's eye, and interest more than anything else was far off. In the distance, one could discern the outlines of a half-toppled building, its crumbling contours jagged against the deep-blue sky. It was an old building of the dead Martians—the Martians who had embellished their civilization with huge, ornately carved stones; and then had died, leaving only the enormous blocks behind on a desolate waste land as mute testimony that once they had lived proudly.

"Our children will rebuild Mars," Dayton murmured to his colleague. "They will pick up that torch, and rekindle it!"

Dr. L'Hai shrugged the thought away. He cared little for the extinct generations of Martians, only for the new one, budding carefully under the hands of Earth-science. And then the air in their head-covering plastic bubbles had run short, and they had returned clumsily in the vague and always-alien atmosphere toward their bubble-home, where the generators made air that was always fresh and breathable.

And now here was Bar, one of those babies grown, burnt by an alien sun, and an alien defiance. "We did much too good a job," the professor thought again, and waited for the young man to speak.

"You're looking at me," Bar boomed. He didn't need a microphone; his resonant voice carried easily. "I'm different from you now, aren't I, Professor?" He didn't wait for an answer. "Yes, I'm different. We're all different. We can breathe this air while you must stay in your domes. We are strong and big. You, and all your kind—are weak and puny.

"You made one mistake, Professor Dayton. You carefully nurtured us, fifty-three kids, so that we could breathe and walk on Mars as free men. You did it, Professor, and it was a marvelous job.