Half Life by Hal Clement

might restore his morale.
    “How does the air density match norm for this height? It should be greater if there’s such a huge downdraft.”
    “It is. Qualitatively this could explain the effect.”
    “And quantitatively?”
    “Unanswerable until the vector analysis is more nearly complete. More data will be needed for that.”
    Another thought restored Belvew’s self-esteem even further, and he voiced it before the analyzer beat him again.
    “Is there enough more smog in the air to account for the higher density?”
    A human voice cut in. Even now it sounded slightly amused, though no one knew why.
    “Wouldn’t more polymer drop the density? It’s made from the surrounding gases, and would use them up as it’s produced.”
    “It would drop volume, Maria. The mass would still be there and contributing to pressure, I’d say; and that would start inflow, which would carry solid and liquid particles from a distance—” The debate was interrupted.
    “The inflow wouldn’t be in. It would be around. There’s Coriolis force even with a sixteen-day rotation and small planet size, and no surface friction fifty kilos up.” The new voice was Arthur Goodall’s, and no one added anything for a moment; the old fellow had an annoying habit of being right, aside from being officially their commander. Belvew was about to take a chance on mentioning the minuteness of the Coriolis effect, but was saved by Status’s voice.
    Goodall himself, in his sealed quarters two hundred meters from Belvew’s and closest of all to the station’s spin axis, paid no attention to what the computer said. He had known as the words left his mouth that his reasoning was sloppy. It was getting constantly harder for him to think coherently, and more and more of his time was being wasted wondering how long he could be useful at all to the project.
    The pain kept getting worse, and distraction from it more difficult.
    Of course he couldn’t work all the time, or even all the time he was awake. Rest and relaxation were essential, but relaxation which would hold the attention firmly was, he had found, almost a contradiction in terms. Reading was better than watching shows, he knew. He suspected that this was because it was a less passive activity, but he had never raised the question publicly and had therefore never been obliged to produce a challenging hypothesis. He had been told long ago that the discomfort of SAS—synapse amplification syndrome—was less severe than that of shingles, but he had never learned how his informant knew. If anyone had ever suffered from both it must have been at different times for the effects to be distinguishable, and whichever had been experienced later would have been remembered as being worse.
    Arthur Goodall had the normal, reasonable mistrust of data dependent solely on human memory, and a chain of human memories was far worse. Besides, he knew of no reliable technique for actually measuring pain, though he had heard of units intended for the purpose.
    He knew all he wanted to about SAS. Unlike shingles, it affected every square centimeter of his skin at one time or another, but caused no external markings. Like shingles and chicken pox, it was produced by a virus, one which had been identified and mapped within weeks of the first recognition of the syndrome.
    It differed from the shingles/chicken pox agent in only four amino acids at specific points plus one bundle, perhaps originally an independent organism, which rendered it unresponsive to both natural and engineered human immune systems. The four acids were few enough to be explained by natural mutation, but numerous enough to make human tampering a reasonable suspicion; the bundle was natural, but might have joined the virus either with or without human assistance. It made no difference to Goodall whether he should be blaming nature’s indifference or human malice; the molecular engineers who now made up most of the medical profession had not yet