Nuwell seemed to have a better grasp of the subject. He nodded his dark, curly head frequently, and occasionally asked a question or two.

"Surgery is performed with a concentrated electron stream on the cells of the early embryo," said Goat. "I call it surgery, but actually it is an alteration of the structure of certain specific genes which govern the characteristics I am attempting to change. Such changes would, of course, then be transmitted on down to any progeny.

"The earlier the embryo is caught, the easier and surer the surgery, because when it has divided into too many cells the very task of dealing with each one separately makes the time requirement prohibitive, besides multiplying the chance for error. The Martians have a method of altering the physical structure and genetic composition of a full-grown adult, but this is far beyond the stage I've reached."

"The Martians?" repeated Nuwell in astonishment. "You mean the Martian natives? They're nothing but degenerated animals!"

"You're wrong," replied Goat. "I know that's the general opinion, but I had considerable contact with them a good many years ago. Perhaps most of them are little more than strange animals. No one really knows. They live simple, animal-like lives, holed up in desert caves, and they're rarely communicative in any way. But I know from my own experience that some of them, at least, are still familiar with that ancient science that they must have possessed when Earth was in an earlier stage of life than the human."

"This ... child ... that brought us the wine is one of the products of your experiments?" asked Nuwell.

"Yes. Petway's pretty representative of the children, I'm afraid. I've been trying to determine what went wrong. It could be an inaccuracy in dealing with the genetic structure itself, or a failure to follow exactly the same pattern of change in moving from one cell to another in the embryo. If I could only catch one at the single cell stage!

"None of the children has turned out as well as my first two experiments, Brute and Adam. Both of them were born about twenty-five years ago—terrestrial years, that is—and developed into normal, even superior physical specimens. Unfortunately, their mental development was retarded. Adam was the brighter of the two, and Brute killed him tonight, shortly before your arrival."

Maya shivered.

"Somehow, it seems horrible to me, experimenting with human lives this way," she said.

"It's being done for a good cause, Maya," said Nuwell. "Dr. Hennessey's objective is to help man live better on Mars. After all, there is nothing nobler than the individual's sacrifice of himself for his fellows, whether it's voluntary or involuntary."

"But what about the mothers of these children?" asked Maya.

"The big problem is to reach them as soon as possible after conception," said Goat, misinterpreting her question. "We do this by magnetic detectors, which report instantly the conjunction of the positive and negative. The surgery is performed, as quickly as possible, utilizing the suspended animation technique which is being developed toward interstellar travel."

"I wasn't asking about the technical aspects," said Maya. "What I want to know is, what sort of mothers will permit you to experiment this way on their unborn children, especially seeing the results you've already obtained?"