Dr. Grimwood smiled slightly. "Don't worry. In the first place, he didn't have it—he only thought he did. And if he had, you couldn't catch it, even minus your pressure-suit. The malady is not transmissible among humans. I almost wish it were, since we would have been obliged to learn a great deal more about it than we have."
"You say he thought he had it—was the stuff in the hypodermic some kind of antidote, then?"
"Undoubtedly," said the doctor. "And since there is only one antidote known, it explains what happened to the rest of the jade they brought along."
"That's right!" exclaimed Archer. "I remember having heard that now. The jade itself is the only antidote. But then—why did he die?"
"Because," said Dr. Grimwood, "the antitoxin, where the infection has not occurred, is a deadly and swift poison."
The doctor paused, then spoke bitterly: "There is some reason for believing that the jade, or end-product, might be rendered non-toxic in itself—if it were obtainable for experimentation. But it's not. They'll inject the stuff in their own skins to save same—one wealthy woman even mixed herself a million-dollar martini in order to commit suicide—but when it comes to turning over the smallest fragment to a laboratory, even billionaire philanthropists are restrained by their wives. And the specimens are never cut or ground since it wouldn't enhance their luminescence, so there aren't even any scraps for the hungry researcher.
"Anyhow, my guess is that these prospectors started off with their samples not too long after exposure. They could have been well out of the atmosphere before the three-and-a-half hour deadline. As it approached, they evidently killed the lights in order to watch each other for the symptomatic aura. Even though the probability was pretty high of at least one of them being infected, they most likely wouldn't have prepared any of the precious solution in advance. Fortunately, it doesn't take long—-you merely dissolve a minimum of ten carats in a little alcohol, and it's ready to inject.
"The fellow who was later killed must have developed the aura and been told about it in good faith, because I saw the needle-mark on his arm. Then came trouble. The other fellow happened to be one of the 20 percent minority who are immune. He failed to show the symptom, but suspected his colleague of lying about it. He probably kept him covered with his gun while he cut the power so that even the control lights would be out. Then he tried to tell by the reflection of his naked torso in the observation ports whether he had the fatal glow. It must have been a tense and ironic situation.
"Whether he was deceived by a diffusion of sunlight in the heavy vitreon or by his own taut nervous system, he evidently fancied he saw the aura, and shot his comrade in a fit of rage. Then he turned the equally fatal hypodermic on himself."