Renfrew sat down in his swivel chair. "Sorry if I'm a bit tense this morning, Greg." He ran thick fingers through his hair. "I've been working evenings as well as days–may as well use the light–and I'm probably tired.
But mainly I'm frustrated. I keep getting noise and it scrambles up the signals."
A sudden flurry of subdued activity in the lab caught their attention.
The technicians who had been casually chatting a minute before were now looking purposeful and prepared. Peterson was threading his way across the lab floor. He came to the door of Hunfredo's office and nodded curtly to the two men.
"Sorry I'm late, Dr. Renfrew," he said, offering no explanation, "Shall we start on it right away?"
As Peterson turned towards the lab again, Markham noticed with mild surprise the caked mud on his elegant shoes, as though he had been walking in ploughed fields.
It was 10:47 a.m. Renfrew began tapping slowly on the signal key.
Markham and Peterson stood behind him. Technicians monitored other output from the experiment and made adjustments.
"It's this easy to send a message?" Peterson asked.
"Simple Morse," Markham said.
"I see, to maximize the chances of its being decoded."
"Damn!" Renfrew suddenly stood up. "Noise level has increased again."
Markham leaned over and looked at the oscilloscope face. The trace danced and jiggled, a scared random field. "How can there be that much noise in a chilled indium sample?" Markham asked.
"Christ, I don't know. We've had trouble like this all along."
"It can't be thermal."
"Transmission is impossible with this going on?" Peterson put in.
"Of course," Renfrew said irritably. "Broadens the tachyon resonance line and muddles up the signal."
"Then the experiment can't work?"
"Bloody hell, I didn't say that. There's just a holdup. I'm sure I can find the problem."
A technician called down from the platform above. "Mr. Peterson?
Telephone call, says it's urgent."
"Oh, all right." Peterson hastened up the metal stairway and was gone.
Renfrew conferred with some technicians, checked readings himself, and fretted away several minutes. Markham stood peering at the oscilloscope trace.
"Any idea what it could be?" he called to Renfrew.
"Heat leak, possibly. Maybe the sample isn't well insulated from shocks, either."
"You mean people walking around the room, that sort of thing?"
Renfrew shrugged and went on with his work. Greg rubbed a thumbnail against his lower lip and studied the yellow noise spectrum on the green oscilloscope screen. After a moment he asked, "Have you got a correlator you could use on this rig?"
Renfrew stopped for a moment, thinking. "No, none here. We have no use for one."
"I'd like to see if there is any structure we could bring out of that noise."
"Well, I suppose we could do that. Take a while to scrounge up something suitable."
Peterson appeared overhead. "Sorry, I'm going to have to go to a secured telephone. Something's come up." Renfrew turned without saying anything. Markham climbed the stairway.
"I think there will be a delay in the experiment, anyway."
"Ah, good. I don't want to return to London just yet, without seeing it through. But I'll have to talk to some people on a confidential telephone line. There's one in Cambridge. It will probably take an hour or so."
"Things are that bad?"
"Seems so. That large diatom bloom off the South American coast, Atlantic side, appears to be expanding out of control."
"Bloom?"
"Biologist's word. It means the phytoplankton are coming to terms with the chlorinated hydrocarbons we've been using in fertilizer. But there's something more to this one. The technical people are scrambling to find out how this case differs from the earlier, smaller effects on the ocean food chain."
"I see. Can we do anything about it?"
"I don't know. The Americans have some controlled experiments in the Indian Ocean, but I gather progress is slow."
"Well, I won't keep you from the telephone. I've got something to work on, an idea about John's experiment. Say, do you know the Whim?"
"Yes, it's in Trinity Street. Near Bowes & Bowes."
"I'll probably need a drink and some food in an hour or so. Why don't we meet there?"
"Good idea. See you round midday."
The Whim was packed with undergraduates. Ian Peterson pushed his way through a crowd near the door and stood for a moment trying to get his bearings. The students near him were passing jugs of beer over each other's heads and some spilled on him. Peterson took out a handkerchief and wiped it off with distaste. The students had not noticed. It was the end of the academic year and they were in boisterous spirits. A few were already drunk. They were talking loudly in dog Latin, a parody of some official function they had just attended.
"Eduardus, dona mihi plus beerus!" shouted one.
"Beerus? O Deus, quid dicit? Ecce sanguinus barbarus!" another declaimed.
"Mea culpa, mea maxima culpa!" the first speaker responded in mock contrition. "But what's beer in bloody Latin?"
Several voices answered. "Alum!" "Vinum barbaricum!" "Imbibius hopius!" There were shouts of laughter. They thought they were being very witty. One of them, hiccuping, slid gently to the floor and passed out. The second speaker raised his arm above him and solemnly intoned.
"Requiescat in pace. Et lux perpetua something or other."
Peterson moved clear of them. His eyes were becoming accustomed to the comparative gloom after the brightness of Trinity. On the wall a yellowed poster announced that some menu items were discontinued–temporarily, of course. In the center of the pub a large coal range popped and hissed. An harassed cook presided over it, shifting pans from smaller rings to larger ones and back. Whenever he lifted a pan from one of the rings, a glow of light from inside the range momentarily lit his hands and perspiring face, so he abruptly loomed like an earnest, orange ghost. Students at tables around the stove called encouragement to him.
Peterson made his way across the crowded eating section, through blue curls of pipe smoke layering the air. The acrid tang of marijuana reached him, mingled with the odors of tobacco, cooking oil, beer and sweat.
Someone called his name. He peered around until he saw Markham in a side booth.
"It's chancy finding anyone here, isn't it?" Peterson said as he sat down.
"I was just ordering. Lots of salads, aren't there? And plates full of crappy carbohydrates. There doesn't seem to be much worth eating these days."
Peterson studied the menu. "I think I may have the tongue, though it's incredibly expensive. Any kind of meat is just impossible."
He grimaced. "I don't see how you can eat tongue, knowing it came out of some animal's mouth."
"Have an egg, instead?"
Markham laughed. "I suppose there's no way to turn. But I think I'll splurge and have the sausages. That should do up my budget pretty nicely."
The waiter brought Peterson's ale and Markham's Mackeson Stout.
Peterson took a big swallow. "They allow marijuana here, then?"
Markham looked around and sniffed the air. "Dope? Sure. All the mild euphorics are legal here, aren't they?"
"They have been for a year or two. But I thought by social convention, if there's any of that left, one didn't smoke it in public places."
"This is a university town. I expect the students were smoking it in public long before it was legalized. Anyway, if the government wants to distract people from the news, there's no point in requiring them to do it only at home," Markham said mildly.
"Ummm," Peterson murmured.
Markham stopped his Mackeson stout short of his mouth and looked at him. "You're being noncommittal. I guessed right, then? The government had that in mind?"
"Let's say it was brought up."
"What's the Liberal government going to do about these drugs that increase human intelligence, then?"
"Since I moved up to the Council I haven't had a great deal of contact with those problems."
"There's a rumor the Chinese are way ahead on them."
"Oh? Well, I can scotch that one. The Council had an intelligence report on precisely that point last month."
"They gather intelligence on their own members?"
"The Chinese are formal members, but–well, look, the problems of the last few years have been technical. Peking has enough on its hands without meddling into subjects where they have no research capability."
"I thought they were doing well."
Peterson shrugged. "As well as anyone can with a billion souls to care for. They're less concerned with foreign matters these days. They're trying to slice up precisely equal portions of an ever-diminishing pie."
"Pure communism at last."
"Not so pure. Equal slices keeps down unrest due to inequality. They're reviving terraced farming, even though it's labor-intensive, to get food production up. The opiate of the masses in China is groceries. Always has been. They're stopping use of energy-intensive chemicals in farming, too. I think they're afraid of side effects."
"Such as the South American bloom?"
"Dead on." Peterson grimaced. "Who could've foreseen–?"
From the crowd there came a sudden, rattling cry. A woman surged up from a nearby table, clutching at her throat. She was trying to say something. Another woman with her asked, "Elinor, what is it? Your throat? Something caught?"
The woman gasped, a rasping cough. She clutched at a chair. Heads turned. Her hands went to her belly and her face pinched with a rush of pain. "I–it hurts so–" Abruptly she vomited over the table. She jerked forward, hands clutching at herself. A stream of bile spattered over the plates of food. Nearby patrons, frozen until this moment, frantically spilled from chairs and backed away. The woman tried to cry out and instead vomited again. Glasses smashed to the floor; the crowd moved back.
"He–elp!" the woman cried. A convulsion shook her. She tried to stand and vomited over herself. She turned to her companion, who had retreated to the next table. She looked down at herself, eyes glazed, and pressed her palms to her belly. Hesitantly she stepped back from the table. She slipped suddenly and crashed to the floor.
Peterson had been shocked into immobility, as had Markham. As she fell he leaped to his feet and dashed forward. The crowd muttered and did not move. He leaned over the woman. Her scarf was tangled about her neck. It was twisted and sour with puke. He yanked at it, using both hands. The fabric ripped. The woman gasped. Peterson fanned the air around her, creating a breeze. She sucked in air. Her eyes fluttered. She stared up at him. "It ... it hurts... so ..."
Peterson scowled up at the surrounding crowd. "Call a doctor, will you?
Bloody hell."
The ambulance had departed. The Whim staff were busy mopping up.
Most of the patrons were gone, driven off by the stench. Peterson came back from the ambulance, where he had followed, making sure the attendants had a sample of her food.
"What did they say it was?" Markham asked· "No idea. I gave them the sausage she'd been eating. The medic said something about food poisoning, but those weren't any poisoning symptoms I've ever heard about."
"All we've been hearing about impurities–"
"Maybe." Peterson dismissed the idea with a wave of his hand. "Could be anything, these days."
Markham sipped meditatively on his stout. A waiter approached bearing their food. "Tongue for you, sir," he said to Peterson, placing a platter. "And sausage here."
Both men stared at their meals. "I think ..." Markham began slowly.
"I agree," Peterson followed up briskly. "I believe we'll be skipping these.
Could you fetch me a salad?"
The waiter looked dubiously at the plates. "You ordered this."
"So we did. Surely you don't expect us to choke it down after what's just happened, do you? In a restaurant like this?"
"Well, I dunno, the manager, he says–"
"Tell your manager to watch his raw materials or I'll bloody well have this place closed down. Follow me?"
"Christ, no reason to–"
"Just tell him that. And bring my friend here another stout."
When the Waiter had backed away, obviously unwilling to confront either Peterson or the manager, Markham murmured, "Great. How'd you know I'd prefer another stout?"
"Intuition," he said with weary camaraderie.
They had both had more drinks when Peterson said, "Look, it's Sir Martin who's really the technical type on the British delegation. I'm a nonspecialist, as they call it. What I want to know is, how in hell do you get around this grandfather paradox bit? That fellow Davies explained about the discovery of tachyons right enough, and I accept that they can travel into our past but I still can't see how one can logically change the past."
Markham sighed. "Until tachyons were discovered, everybody thought communication with the past was impossible. The incredible thing is that the physics of time communication had been worked out earlier, almost by accident, as far back as the 1940s. Two physicists named John Wheeler and Richard Feynmann worked out the correct description of light itself, and showed that there were two waves launched whenever you tried to make a radio wave, say."
"Two?"
"Right. One of them we receive on our radio sets. The other travels backward in time–the 'advanced wave,' as Wheeler and Feynmann called it."
"But we don't receive any message before it's sent."
Markham nodded. "True but the advanced wave is there, in the mathematics. There's no way around it. The equations of physics are all time-symmetric. That's one of the riddles of modern physics. How is it that we perceive time passing, and yet all the equations of physics say that time can run either way, forward or backward?"
"The equations are wrong, then?"
"No, they're not. They can predict anything we can measure–but only as long as we use the 'retarded wave,' as Wheeler and Feynmann called it.
That's the one that you hear through your radio set."