The new laboratory was still being fitted when they arrived. It had been dug into one of the few real cliffs in this section of Mars. The power plant had been installed, complete with a steam plant that would operate off sunlight in the daytime through a series of heat valves that took in a lot of warm air and produced smaller amounts hot enough to boil water.
"I'll see you whenever I can," Jake said. "But mostly, you're going to be somewhat isolated so they won't trace you. Let them think they goofed with the shuttles and hit you and Chris. Anything you need?"
"Guinea pigs," Doc told him sarcastically. It was meant as a joke, though a highly bitter one. Jake nodded and left them.
Doc opened the cots as Chris came in, not bothering to unpack the equipment. "Hit the sack, Chris," he told her.
She looked at him doubtfully. "You almost said that the way you'd address a human being, Dan. You're slipping. One of these days you'll like me again."
"Maybe." He was too tired to argue. "I doubt it, though. Forget it and get some sleep."
She watched him silently until he got up to turn out the light. Then she sighed heavily. "Dan?"
"I never got a divorce. The publicity would have been bad. But anyway, we're still married."
"That's nice." He swung to face her briefly. "And they found the radio in the microscope. Better get to sleep, Chris."
"Oh." It was a quiet exclamation, barely audible. There was a sound that might have been a sniffle if it had come from anyone else. Then she rolled over. "All right, Dan. I still want to help you."
He cursed himself for a stupid fool for telling her. Fatigue was ruining what judgment he had. From now on, he'd have to watch her every minute. Or had she really seen the value of the research by now? She wasn't a fool. It should have registered on even her stubborn mind. But he was too sleepy to think about it.
She had breakfast ready in the morning. She made no comment on what had been said during the night. Instead, she began discussing a way to keep one of the organic antibiotics from splitting into simpler compounds when they tried to switch it over to Mars-normal. They were both hopelessly bad chemists and biologists, but there was no one else to do the work.
Chris worked harder than ever during the day.
Just after sundown, Jake came in with a heavy box. He dropped it onto the floor. "Mice!"
Doc ripped off the cover, exposing fine screening. There were at least six dozen mice inside!
"Harkness found them," Jake explained. "A hormone extraction plant used them for testing some of the products. Had them sent by regular shipments from Earth. Getting them cost a couple of men, but Harkness claims it's worth it. He's a good man on a raid. Here!"
He'd gone to the doorway again and came back with another box, this one crammed with bottles and boxes. "They had quite a laboratory, and Harkness picked out whatever he thought you could use."
Chris and Doc were going through it. The labels were engineering ones, but the chemical formulae were identification enough. There were dozens of chemicals they hadn't hoped to get.
"Anything else?" Doc finally asked as they began arranging the supplies.
"More runners. A lot more. We're still holding things down, but it's reaching a limit. Panic will start in the camps if this keeps on. But that's my worry. You stick to yours."
Several of the new chemicals showed promise in the tubes. But two of them proved fatal to the mice and the others were completely innocuous in the little animal's bodies, both to mouse and to germ. The plague was much hardier in contact with living cells than in the artificial environment of the culture jars.
They lost seven mice in two days, but that seemed unimportant; the females were already living up to their reputations, nearly all pregnant. Doc didn't know the gestation period, but he remembered that it was short.
"Funny they all started at the same time," he commented. "Must have been shipped out separately or else been kept apart while they were switched over to Mars-normal. Something interrupted their habits, anyhow."
A few nights later they learned what it was. There was a horrible squealing that woke him out of the depths of his sleep. Chris was already at the light switch. As light came on, they turned to the mouse box.
All the animals were charging about in their limited space, their little legs driving madly and their mouths open. What they lacked in size they made up in numbers, and the din was terrific.
But it didn't last. One by one, the mice began dropping to the floor of the cage. In fifteen minutes, they were all dead!
It was obviously the plague, contracted after having their metabolism switched. Women were sterile for some time after Selznik's migraine struck, and the same must have been true of the mice. They must have contracted the plague at about the same time and reached fertility together. Somehow, the plague incubation period had been shortened to fit their life span; the disease was nothing if not adaptive.
Chris prepared a slide in dull silence. The familiar cell was there when Doc looked through the microscope. He picked up one of the little creatures and cut it open, removing one of the foetuses.
"Make a film of that," he suggested.
She worked rapidly, scraping out the almost microscopic brain, dissolving out the fatty substance, and transferring the result to a film. This time, even at full magnification, there was no sign of the filaments that were always present in diseased flesh. The results were the same for the other samples they made.
"Something about the very young animal or a secretion from the mother's organs keeps the bug from working." Doc reached for a bracky weed and accepted a light from Chris without thinking of it. "Every kid I've heard about contracted the plague between the second and third year. None are born with it, none get it earlier. I've suspected this, but now here's confirmation."
Chris began preparing specimens, while Doc got busy with tubes of the culture. They'd have to test various fluids from the tiny bodies, but there were enough cultures prepared. Then, if the substance only inhibited growth, there would be a long, slow test; if it killed the bugs, they might know more quickly.
Jake came in before the final tests, but waited on them. Doc was studying a film in the microscope. He suddenly motioned excitedly for Chris.
"See the filaments? They're completely disintegrated. And there's one of the big cells broken open. We've got it! It's in the blood of the foetus. And it must be in the blood of newborn children, too!"
Jake looked at the slide, but his face was doubtful.
"Maybe you've got something, Doc. I hope so. And I hope you can use it." He shook his head wearily. "We need good news right now. A couple of big rockets just reached the station and they've been sending shuttles back and forth a mile a minute. Nobody can figure how they got here so fast or what they're for. But it doesn't look good for us!"
Susceptibility Doc could feel the tension in the village where GHQ was temporarily located long before they were close enough for details to register. The people were gathered in clusters, staring at the sky where the station must be. A few were pacing up and down, gesticulating with tight sweeps of their arms.
One woman suddenly went into even more violent action. She leaped into the air and then took off at a rapid trot, then a run. Her hands were tearing at her clothes and her mouth seemed to be working violently. She was halfway to the top of the nearest dune before a rifle cracked. She dropped, to twitch once and lie still.
Almost with her death, another figure leaped from one of the houses, his face bare of the necessary aspirator. He took off at a violent run, but he was falling from lack of air before the bullet ended his struggles.
The people suddenly began to move apart, as if trying to get away from each other. For weeks they had faced the horror with courage; now it was finally too much for them.
Tension mounted as no news came from the cities. Doc noticed that it seemed to aggravate or speed up the disease. He saw three men shot in the next half-hour.
He was trying to calm them with word of a possible cure for the plague, but their reactions were as curiously dull as those of Jake had been. As he spoke, they faced him with set expressions. At his mention of the need for the blood of young children, they turned from him, sullenly silent.
Jake came over, nodding unhappily. "It's what I was afraid might happen, Doc. George Lynn! Tell Doc what's wrong."
Lynn was reluctant, but he finally stumbled out his explanation. "It ain't like you, Doc. Comes from that Lobby woman you got. It's her dirty idea. We've seen the Lobby doctors cutting open our kids, poisoning their blood, and bleeding them dry. That ain't gonna happen again, Doc. You tell her it ain't!"
Doc swore as he realized their ignorance. An unexplained vaccination looked like poisoning of the blood. But he couldn't understand the bleeding part until Jake filled him in.
"Northport infant's wing. Each department has its own blood bank and donation is compulsory. Southport started it a couple months ago, too."
The long arm of the Lobby had reached out again. Now if he ever got them to try the treatment, it would be only after long sessions of preparing them with the facts, and there was hardly enough time for the crucial work!
By afternoon, Judge Ben Wilson reached them. His voice shook with fatigue as he climbed up to address the crowd through a power megaphone. "Southport's going crazy." He had to pause for breath between each sentence. "Earth's pulling back all the important people. They're packing them into the ships. They're leaving only colonials with no Earth rights. Those ships left when they decided the plague was coming from here. They won't let anybody back until the plague is licked. There won't be an Earth technician on Mars tomorrow."
"No bombs?" someone called.
"No bombs. The ships must have started before you rebelled, maybe meant honestly to save their own kind. But now it's a military action, and don't think it won't mean trouble. The poor devils in the city bet on the wrong horse. Now they can't run their food factories or anything else for long. Not without technicians. They've got to whip you now. Up to this time, they've been fighting for the Lobbies. Now they'll fight you for their own bellies to get your supplies. And they've still got shuttle rockets and fuel for them. Now beat it. I gotta confer with Jake."
Doc started after the judge, but Dr. Harkness caught his arm and drew him aside. Chris followed.
"I've found another epidemic," Harkness told them. "Over at Marconi. It's kept me on the run all night, and now half the village is down with it. Starts like a common cold, runs a fair fever, and the skin breaks out all over with bright red dots...."
He went on describing it. Chris began asking him about what medical supplies he had brought with him, pilfered from Northport hospital. She seemed to know what it was, but refused to say until she saw the cases. Doc also preferred to wait. Sometimes things weren't as bad as they seemed, though usually they were worse.
Marconi was dead to all outward appearances, with nobody on the streets. It had been a village of great hopes a week before, since this was where they had decided to experiment with switching the people back to Earth-normal. They'd had the best chance of survival of anyone on Mars until this came up.
Three people lay on the beds in the first house Harkness led them to. The room was darkened, and a man was stumbling around, trying to tend the others, though the little spots showed on his skin. He grinned weakly. "Hi, Doc. I guess we're making a lot of trouble, ain't we?"
Chris gave Doc no chance to answer. "Just as I thought. Measles! Plain old-fashioned measles."
"Figured so," the sick man said. "Like my brother back on Earth."
The others looked doubtful, but Doc reassured them. Chris should know; she'd worked in a swanky hospital where the patients were mostly Earth-normal. Measles was one of the diseases which was foiled by the metabolism switch. Well, at least they wouldn't have to be quarantined here.
Chris finished treating the family with impersonal efficiency, discussing the symptoms loudly with Harkness. "It's a good thing it isn't serious!"
"No," Harkness answered bitterly. "Not serious. It's only killed five children and three adults so far!"
"It would, here," Doc agreed unhappily. He led Chris out of the room on the pretext of washing his hands. "It's serious enough to force us to abandon the whole idea of going back to Earth-normal. Measles today, smallpox, tuberculosis, scarlet fever and everything else tomorrow. These people have lived Mars-normal so long their natural immunity has been destroyed. On Earth where the disease was everywhere, kids used to pick up some immunity with constant exposure, even without what might be called a case of the disease. Here, the blood has no reason to build antibodies. They can be killed by things people used to laugh at. How the disease got here, I don't know. But it's here. So we'll have to give up the idea of switching back to Earth-normal."
He gathered up one of the kits and started toward the other houses. "And Lord knows how long it will take to get the blood for the other treatment, even if it works."
They worked as a team for a while, with Harkness frowning as he watched Chris. Finally the young doctor stopped Chris outside the fifth house. "These are my patients, Dr. Ryan. I left the Lobby because I didn't believe colonials were mere livestock. I still feel the same. I appreciate your help in diagnosis and methods of treatment. But I can't let you handle my patients this way."
"Dan!" She swung around with eyes glazing. "Dan, are you going to stand for that?"
"I think you'd better wait in the tractor, Chris."
He was lucky enough to catch the kit she threw at him before its precious contents spilled. But it wasn't luck that guided his hand to the back of her skirt hard enough to leave it stinging.
Her face froze and she stormed out. A moment later they heard the tractor start off.
But Doc had no time to think of her. He and Harkness split up and began covering the streets, house by house, while he passed on the word to abandon the metabolism switch and go back to Mars-normal.
Jake sent two other doctors to relieve them late in the evening. Things were somewhat quieter at GHQ as Doc reported the events at Marconi.
"Where's Dr. Ryan?" Jake asked at last.
Doc exchanged glances with Harkness. "She isn't in the lab?"
"Wasn't there an hour ago."
Doc cursed himself for letting her go. With the knowledge that the radio in the mike was disabled, she'd obviously grabbed the first chance to report back. And with her had gone news of the only cure they had found.
Jake took it as philosophically as he could, though it was a heavy blow to his hopes. They spent half the night looking for her tractor, on the chance that she might have gotten lost or broken down, but there was no sign of it.
She was waiting in the laboratory when he returned at dawn. Her face was dirty and her uniform was a mess. But she was smiling. She got up to greet him, holding out two large bottles.
"Infant plasma--straight from Southport. And if you think I had it easy lying my way in and out of the hospital, you're a fool, Dan Feldman. If the man who took my place there hadn't been a native idiot, I never would have gotten away with it."
The things he had suspected could still be right, he realized. She could have reported everything to the Lobby. It was a better explanation than her vague account of bullying her way in and out. But she'd had a rough drive, and he wanted the plasma. Curiously, he was glad to have her back with him. He reached out a hand for the bottles.
She put the bottle on the table and grabbed up a short-bladed knife. "Not so fast," she cried. Her eyes were blazing now. "Dan Feldman, if you touch those bottles until you've crawled across the floor on your face and apologized for the way you treated me the last few days, I'll cut your damned heart out."
He shook his head, chuckling at the picture she made. There were times when he could almost see why he'd married her.
"All right, Chris," he gave in. "I'll be darned if I'll crawl, but you've earned an apology. Okay?"
She sighed uncertainly. Then she nodded and began changing for work.
Immunity They worked through the day in what seemed to be armed truce. There was no coffee waiting for him when he awoke next, as he'd come to expect, but he didn't comment. He went to where she was already working, checking on the results of the plasma on the cultures.
The response had been slower than with the mouse blood, but now the bugs seemed to be dead. The filaments were destroyed, and there were no signs of the big cells. It seemed to be a cure, at least in the culture bottles.
"We'll need volunteers," he decided. "There should be animals, but we don't have any. At least this stuff isn't toxic. We need a natural immune and someone infected. Two of each, so one can be treated and the other used for a control. Makes four. Not enough to be sure, but it will have to do."
"Two," Chris corrected. "You're not infected, I am."
"Two others," he agreed. "I'll get them from Jake."
Most of GHQ was out on the street, but Doc found Jake inside the big schoolroom where he enjoyed his early morning bracky and coffee. The chief listened and agreed at once, turning to the others in the room.
"Who's had the jumping headache? Okay, Swanee. Who never had it?" He blinked in surprise as three men nodded out of the eight present. "I guess you go, Tom."
The two men stood up, tamping out their weeds, and went out with Doc.
Chris had everything set up. They matched coins to decide who would be treated. Doc noticed that Chris would get no plasma, while he was scheduled for everything. He watched her prepare the culture and add the accelerator that would speed development and make certain he and Tom were infected, then let her inject it.
That was all, except for the waiting. To keep conditions more closely alike, they were to stay there until the tests were finished, not even eating for fear of upsetting the conditions. Swanee dug out a pack of worn cards and began to deal while Doc dug out some large pills to use as chips.
It was an hour later when the pain began. Doc had just won the pot of fifty pills and opened his mouth for the expected gloating. He yelled as an explosion seemed to go off inside his head. Even closing his mouth was agony.
A moment later, Tom began to sweat. It got worse, spreading to the whole area of the back of the head and neck. Doc lay on the cot, envying Chris and Swanee who had already been infected naturally. He longed desperately for bracky, and had to keep reminding himself that no drugs must upset the tests. It was the longest day he had ever spent, and he began to doubt that he could get through it. He watched the little clock move from one minute to nine over to half a minute and hung breathless until it hit the nine. There was no question about whether the infection had taken. Now they could dull the agony.
Chris had the anodyne tablets already dissolved in water, and Swanee was passing out three lighted bracky weeds. It took a few minutes for the relief of the anodyne, and even that couldn't kill all the pain. But it didn't matter by comparison. He sucked the weed, mashed it out and began dealing the cards again.
They had a plentiful supply of the anodyne and used it liberally during the night. The test was a speeded-up simulation of the natural course of the disease, where painkiller would take time to get for most people here, but would then be used generously.
Precisely at nine in the morning, Chris began to inject Swanee and Doc with plasma.
Now there was no thought of cards. They waited, trying to talk, but with most of their attention on the clock. Doc had estimated that an hour should be enough to show results, but it was hard to remember that an hour was the guess as to the minimum time.