The news broadcasts the following morning were less hysterical than previously. Because the news itself was far more serious, the announcers found it unnecessary to inject artificial notes of urgency.

Ken listened to his bedside radio as he watched the first tint of dawn above the hills east of the valley. "The flurry of mechanical failures, which was reported yesterday, has reached alarming proportions," the announcer said. "During the past 24 hours garages in every section of the nation have been flooded with calls. From the other side of the Atlantic reports indicate the existence of a similar situation in Europe and in the British Isles.

"Automobile breakdowns are not the most serious accidents that are taking place. Other forms of machinery are also being affected. A crack train of the Southern Pacific came to a halt last night in the Arizona desert. All efforts of the crew to repair the stalled engine were fruitless. A new one had to be brought up in order for the passengers to continue on their way early this morning.

"From Las Vegas comes word that one of the huge generators at Hoover Dam has been taken out of service because of mechanical failure. Three other large municipalities have had similar service interruptions. These are Rochester, New York, Clinton, Missouri, and Bakersfield, California.

"Attempts have been made to find some authoritative comment on the situation from scientists and Government officials. So far, no one has been willing to commit himself to an opinion as to the cause of this unexplained and dangerously growing phenomenon.

"Yesterday it was jokingly whispered that the comet was responsible. Today, although no authority can be found to verify it, the rumor persists that leading scientists are seriously considering the possibility that the comet may actually have something to do with the breakdowns."

Ken turned off the radio and lay back with his hands beneath his head, staring at the ceiling. His first impulse was to ridicule again this fantastic idea about the comet. Yet, there had to be some explanation.

He had seen enough of the engines in Art's garage last night to know they had suffered no ordinary mechanical disorder. Something had happened to them that had never happened to engines before, as far as he knew. The crankshafts were immovable in their bearings. The pistons had been frozen tight in the cylinders when they tried to remove some of them. Every moving part was welded to its mating piece as solidly as if the whole engine had been heated to the very edge of melting and then allowed to cool.

Apparently something similar was happening to engines in every part of the world. It could only mean that some common factor was at work in London, and Paris, and Cairo, and Mayfield. The only such factor newly invading the environment of every city on the globe was the comet.

It would almost require a belief in witchcraft to admit the comet might be responsible!

Ken arose and dressed slowly. By the time he was finished he heard his father's call to breakfast from downstairs.

Professor Maddox was already seated when Ken entered the dining room. He was a tall, spare man with an appearance of intense absorption in everything about him.

He glanced up and nodded a pleasant good morning as Ken approached. "I hear you worked overtime as an auto mechanic last night," he said. "Isn't that a bit rough, along with the load you're carrying at school?"

"Art asked us to do him a favor. Haven't you seen what's been happening around town?"

"I noticed an unusual number of cars around the garage, and I wondered about it. Has everyone decided to take care of their winter repairs at the same time?"

"Haven't you heard the radio, either, Dad?"

"No. I've been working on my new paper for the Chemical Journal until midnight for the last week. What has the radio got to do with your work as a mechanic?"

Quickly, Ken outlined to his father the events he had heard reported the past two days. "It's not only automobiles, but trains, power plants, ships, everything—"

Professor Maddox looked as if he could scarcely believe Ken was not joking. "That would certainly be a strange set of coincidences," he said finally, "provided the reports are true, of course."

"It's true, all right," said Ken. "It's not a matter of coincidence. Something is causing it to happen!"

"What could that possibly be?"

"There's talk about the comet having something to do with it."

Professor Maddox almost choked on his spoonful of cereal. "Ken," he laughed finally, "I thought you were such a stickler for rigid, scientific methods and hypotheses! What's happened to all your rigor?"

Ken looked down at the tablecloth. "I know it sounds ridiculous, like something out of the dim past, when they blamed comets for corns, and broken legs, and lost battles. Maybe this time it isn't so crazy when you stop to think about it, and it's absolutely the only new factor which could have some worldwide effect."

"How could it have any effect at all—worldwide or otherwise?" Professor Maddox demanded.

"The whole world is immersed in its tail."

"And that tail is so tenuous that our senses do not even detect the fact!"

"That doesn't mean it couldn't have some kind of effect."

"Such as stopping engines? Well, you're a pretty good mechanic. Just what did the comet do to all these stalled pieces of machinery?"

Ken felt his father was being unfair, yet he could scarcely blame him for not taking the hypothesis seriously. "I don't know what the comet did—or could do—" he said in a low voice. "I just know I've never seen any engines like those we took apart last night."

In detail, he described to his father the appearance of the engine parts they had dismantled. "I brought home some samples of metal we cut from the engine blocks with a torch. Would you take them up to the laboratory at the college and have them examined under the electron microscope?"

"I wouldn't have time to run any such tests for several days. If you are intent on pursuing this thing, however, I'll tell you what I'll do. You and your science club friends can come up and use the equipment yourselves."

"We don't know how!"

"I'll arrange for one of the teaching fellows to show you how to prepare metallic samples and operate the electron microscope."

Ken's eyes lighted. "Gee, that would be great if you would do that, Dad! Will you, really?"

"Come around after school today. I'll see that someone is there to help you."

Art Matthews was disappointed when Ken called and said none of the science club members would be around that afternoon. He couldn't keep from showing in his voice that he felt they were letting him down.

"It's not any use trying to get those engines running," Ken said. "The pistons would never come out of most of them without being drilled out. We're not equipped for that. Even if we got things loosened up and running again, what would keep the same thing from happening again? That's what we've got to find out."

Art was unable to accept this point of view. He held a bewildered but insistent belief that something ought to be done about the mounting pile of disabled cars outside his garage. "We can get some of them going, Ken. You fellows have got to lend a hand. I can't tackle it without help."

"I'm sorry," Ken said. "We're convinced there's got to be another way to get at the problem."

"All right. You guys do whatever you figure you've got to do. I can probably round up some other help."

Ken hung up, wishing he had been able to make Art understand, but the mechanic would probably be the last person in Mayfield to accept that the comet could have any possible connection with the frozen engines.

As Ken walked to school that morning he estimated that at least 25 percent of the cars in Mayfield must be out of commission. Some of the men in his neighborhood were in their driveways futilely punching their starters while their engines moaned protestingly or refused to turn over at all. Others were peering under the hoods, shaking their heads, and calling across the yards to their neighbors.

In the street, some cars were lugging with great difficulty, but others moved swiftly along without any evidence of trouble. Ken wondered how there could be such a difference, and if some might prove immune, so to speak, to the effect.

He had called a meeting of the club in the chemistry laboratory for an hour before the first class. All of the members were there when he arrived.

Ken called the meeting to order at once. "I guess you've all heard the news broadcasts, and you know what's happening here in town," he said. "Yesterday you talked about the possibility of collecting samples and analyzing the material of the comet's tail. I don't know what you decided. You can fill me in later on that. The problem is a lot more important now than it was yesterday.

"It's beginning to seem as if the presence of the comet may actually be responsible for the wave of mechanical failures. Finding out how and why is just about the biggest problem in the whole world right now."

A babble of exclamations and protests arose immediately from the other members of the group. Al Miner and Dave Whitaker were on their feet. Ted Watkins waved a hand and shouted, "Don't tell us you're swallowing that superstitious junk!"

Ken held up a hand. "One at a time. We haven't got all day, and there's a lot of ground to cover. Ted, what's your comment?"

"My comment is that anybody's got a screw loose if he believes the comet's got anything to do with all those cars being in Art's garage. That stuff went out of fashion after the days of old Salem."

Several of the others nodded vigorously as Ted spoke.

"I guess we do need to bring some of you up to date on the background material," said Ken. "Joe, tell them what we found last night."

Briefly, Joe Walton described the engines they had dismantled. "Something had happened to them," he said, "which had never happened to an engine since Ford drove his first horseless carriage down Main Street."

"It doesn't mean anything!" exclaimed Ted. "No matter what it is, we haven't any basis for tying it to the comet."

"Can you name any other universal factor that could account for it?" Ken asked. "We have an effect that appears suddenly in Mayfield, Chicago, Paris, and Cairo. Some people say it's the additives in gasoline, but you don't get them showing up simultaneously in all parts of the world. There is no other factor common to every locality where the mechanical failures have occurred, except the comet.

"So I called this meeting to suggest that we expand our project beyond anything we previously had in mind. I suggest we try to determine the exact relationship between the breakdowns and the appearance of the comet."

Big Dave Whitaker, sitting at the edge of the room, rose slowly in his seat. "You've got the cart before the horse," he said. "You've got a nice theory all set up and you want us to beat our brains out trying to prove it. Now, take me. I've got a theory that little green men from Mars have landed and are being sucked into the air intake of the engines. Prove my theory first, why don't you?"

Ken grinned good-naturedly. "I stand corrected, but I won't back down very far. I won't suggest we try to prove the connection with the comet, but I do propose to set up some experiments to discover if there is any relationship. If there is, then what it is. Does that suit you?"

"I'll go along with that. How do you propose to go about it?"

"Let's find out where the rest stand," said Ken. "How about it, you guys?"

"I'll go for it," said Ted, "as long as we aren't out to prove a medieval superstition."

One by one, the others nodded agreement. Joe Walton said intensely, "We'll find out whether it's superstition or not! There's no other possible cause, and we'll prove it before we're through."

Ken smiled and waved him down. "We're working on a hypothesis only. Anyway, here's what I have to suggest by way of procedure: Since the tail of the comet is so rarefied, there aren't many molecules of it in the atmosphere of this entire valley. I don't know just what the mathematical chances of getting a measurable sample are. Maybe you can work out some figures on it, Dave. We'll have to handle an enormous volume of air, so let's get a blower as large as we can get our hands on and funnel the air through some electrically charged filters. We can wash down these filters with a solvent of some kind periodically and distill whatever has collected on them."

"You won't get enough to fill the left eye of a virus suffering from arrested development," said Ted.

"We'll find out when we get set up," said Ken. "My father has agreed to give us access to the electron microscope at the college. Maybe we can use their new mass spectrograph to help analyze whatever we collect."

"If we knew how to use a mass spectrograph," said Ted.

"He's offered to let one of the teaching fellows help us."

"What will all this prove, even if we do find something?" Dave asked. "You'll get all kinds of lines from a spectrogram of atmospheric dust. So what?"

"If we should get some lines that we can't identify, and if we should get those same lines from metallic specimens taken from the disabled engines, we would have evidence of the presence of a new factor. Then we could proceed with a determination of what effect, if any, this factor has on the engines."

Ken looked around the group once more. "Any comments, suggestions, arguments? There being none, we'll consider the project approved, and get to work this afternoon."

As they left to go to their first classes, Ted shook his head gloomily. "Man, you don't know what you're biting off! All we've done so far is build a few ham radios, a telescope, and some Geiger counters. You're talking about precision work now, and I mean pree-cision!"

Throughout the day Ken, too, felt increasing doubts about their ability to carry off the project. It would be a task of tremendous delicacy to analyze such microscopic samples as they might succeed in obtaining. Microchemical methods would be necessary, and none of them had had any experience in that field. His father was an expert with these methods and though he might scold them for tackling such a difficult project, he'd help them, Ken thought. He always had.

This was no ordinary project, however. Ken had no idea how seriously scientists in general were considering the comet as the offender, but certainly they must be working frantically on the problem of the mechanical disorder. Unless they found another cause very soon, they were certain to turn to an analysis of the comet's tail. It would be very satisfying if Ken's group could actually be in the vanguard of such a development.

He tried to ridicule his own conviction that the comet held the key. He had no reason whatever for such a belief, except the fact of the comet's universal presence. How it could stop an automobile engine or a railroad train was beyond his wildest imaginings.

But there was nothing else. Nothing at all.

On the way home after school, there seemed to Ken to be a subtle change that had come over the valley since morning. Along the streets, cars were parked in front of houses to which they did not belong. Little knots of people were standing about, talking in hushed tones. The comet was aflame in the sky.

There seemed to be not merely an awe and an uneasiness in the people, but a genuine fear that Ken could not help absorbing as he moved past them on the sidewalks. Their faces were yellow and flat under the glare of the comet, and they looked at him and at each other as if they were strangers in an alien land.

Almost without being aware of it, Ken found himself running the last half-block before he reached his own home. He burst in the door and called out with forced cheeriness, "Hi, Mom, what's cooking? I'm starved. The whole gang's coming over in a few minutes. I hope you've got something for them."

His mother came out of the kitchen, her face gray with uncertainty. "You'll have to do with sandwiches this afternoon," she said. "I haven't been able to use the electric stove since noon."

Ken stared at her.

"There's something about the power," she went on. "We haven't any lights, either. They say the power station at Collin's Dam went out of commission this morning. They don't know when they'll be able to get it back on."