That night, Ken reported to his father the fate of the engine assembled by Art.

“It did seem too good to be true,” said Professor Maddox. He stretched wearily in the large chair by the feeble heat of the fireplace. “It bears out our observation of the affinity of the dust for metals.”

“How is that?”

“It attaches itself almost like a horde of microscopic magnets. It literally burrows into the surface of the metal.”

“You don’t mean that!”

“I do. Its presence breaks down the surface tension, as we had supposed. The substance actually then works its way into the interstices of the molecules. As the colloid increases in quantity, its molecules loosen the bond between the molecules of the metal, giving them increased freedom of motion.

“This can be aggravated by frictional contacts, and finally we have the molecular interchange that binds the two pieces into one.”

“The only metal that would be clean would be that which had been hermetically sealed since before the appearance of the comet,” said Ken. “Look wouldn’t this affinity of the dust for metal provide a means of purifying the atmosphere? If we could run the air through large filters of metal wool, the dust would be removed!”

“Yes, I’m very sure we could do it that way. It would merely require that we run the atmosphere of the whole Earth through such a filter. Do you have any idea how that could be done?”

“It would work in the laboratory, but would be wholly impractical on a worldwide scale,” Ken admitted. “How will we ever rid the atmosphere of the dust! A colloid will float forever in the air, even after the comet is gone.”

“Exactly,” Professor Maddox said, “and, as far as we are concerned, the whole atmosphere of the Earth is permanently poisoned. Our problem is to process it in some manner to remove that poison.

“During the past few days we have come to the conclusion that there are only two alternatives: One is to process the whole atmosphere by passing it through some device, such as the filter you have suggested. The second is to put some substance into the air which will counteract and destroy the dust, precipitate it out of the atmosphere.”

“Since the first method is impractical what can be used in carrying out the second?”

“We’ve set ourselves the goal of discovering that. We’re hoping to synthesize the necessary chemical compound to accomplish it.”

“It would have to be a colloid, too, capable of suspension in the atmosphere,” said Ken.

“Correct.”

“If we do find such a substance we still have the problem of decontaminating existing metals. We couldn’t build a moving piece of machinery out of any metal now in existence without first cleaning the dust out of its surface.”

“That’s part of the problem, too,” said his father.

Ken resumed his duties in the laboratory the following morning. Dr. Adams had warned him not to walk up College Hill, so he had borrowed the horse Dave Whitaker still had on loan from his uncle. He felt self-conscious about being the only one enjoying such luxury, but he promised himself he would go back to walking as soon as Dr. Adams gave permission.

On the third day, the horse slipped and fell as it picked its way carefully down the hill. Ken was thrown clear, into the deep snow, but the horse lay where it had fallen, as if unable to move. Ken feared the animal had broken a leg. He felt cautiously but could find no evidence of injury.

Gently, he tugged at the reins and urged the horse to its feet. The animal finally rose, but it stood uncertainly and trembled when it tried to walk again.

Ken walked rather than rode the rest of the way home. He took the horse to the improvised stable beside the science shack. There he got out the ration of hay and water, and put a small amount of oats in the trough. The animal ignored the food and drink.

After dinner, Ken went out again to check. The horse was lying down in the stall and the food remained untouched.

Ken returned to the house and said to his father, “Dave’s horse slipped today, and I’m afraid something serious is wrong with him. He doesn’t seem to have any broken bones, but he won’t eat or get up. I think I should go for the vet.”

His father agreed. “We can’t afford to risk a single horse, considering how precious they are now. You stay in the house and I’ll go to Dr. Smithers’ place myself.”

Ken protested. He hated to see his father go out again on such a cold night.

Dr. Smithers grumbled when Professor Maddox reached his house and explained what he wanted. As one of the town’s two veterinarians, he had been heavily overworked since the disaster struck. The slightest sign of injury or illness in an animal caused the Mayor’s livestock committee to call for help.

“Probably nothing but a strained ligament,” Smithers said. “You could have taken care of it by wrapping it yourself.”

“We think you ought to come.”

When the veterinarian finally reached the side of the animal, he inspected him carefully by the light of a gasoline lantern. The horse was lying on his side in a bed of hay; he was breathing heavily and his eyes were bright and glassy.

Dr. Smithers sucked his breath in sharply and bent closer. Finally, he got to his feet and stared out over the expanse of snow. “It couldn’t be,” he muttered. “We just don’t deserve that. We don’t deserve it at all.”

“What is it?” Ken asked anxiously. “Is it something very serious?”

“I don’t know for sure. It looks like it could be anthrax. I’m just afraid that it is.”

Dr. Smithers’ eyes met and held Professor Maddox’s. Ken did not understand. “I’ve heard that name, but I don’t know what it is.”

“One of the most deadly diseases of warm-blooded animals. Spreads like wildfire when it gets a start. It can infect human beings, too. How could it happen here? There hasn’t been a case of anthrax in the valley for years!”

“I remember Dave Whitaker saying his uncle got two new horses from a farmer near Britton just a week before the comet,” said Ken. “Maybe it could have come from there.”

“Perhaps,” said Smithers.

“What can we do?” asked Professor Maddox. “Can’t we start a program of vaccination to keep it from spreading?”

“How much anthrax vaccine do you suppose there is in the whole town? Before we decide anything I want to get Hart and make some tests. If he agrees with me we’ve got to get hold of the Mayor and the Council and decide on a course of action tonight.”

Hart was the other veterinarian, a younger man, inclined to look askance at Dr. Smithers’ older techniques.

“I’d just as soon take your word,” said Professor Maddox. “If you think we ought to take action, let’s do it.”

“I want Hart here first,” said Smithers. “He’s a know-it-all, but he’s got a good head and good training in spite of it. Someday he’ll be a good man, and you’ll need one after I’m gone.”

“I’ll go,” said Ken. “You’ve already been out, Dad. It’s only 4 or 5 blocks, and I feel fine.”

“Well, if you feel strong enough,” said his father hesitantly. Fatigue was obvious in his face.

Dr. Hart was asleep when Ken pounded on his door. He persisted until the veterinarian came, sleepily and rebelliously. Ken told his story quickly.

Hart grunted in a surly voice. “Anthrax! That fool Smithers probably wouldn’t know a case of anthrax if it stared him in the face. Tell him to give your horse a shot of terramycin, and I’ll come around in the morning. If I went out on every scare, I’d never get any sleep.”

“Dr. Hart,” Ken said quietly. “You know what it means if it is anthrax.”

The veterinarian blinked under Ken’s accusing stare. “All right,” he said finally. “But if Smithers is getting me out on a wild-goose chase I’ll run him out of town!”

Smithers and Professor Maddox were still beside the ailing horse when Ken returned with Dr. Hart. No one spoke a word as they came up. Hart went to work on his examination, Ken holding the lantern for him.

“Here’s a carbuncle, right back of the ear!” he said accusingly. “Didn’t anybody notice this earlier?”

“I’m afraid not,” Ken admitted. “I guess I haven’t taken very good care of him.”

“Ken’s been in the hospital,” Professor Maddox said.

“I know,” Hart answered irritably, “but I think anybody would have noticed this carbuncle; these infections are characteristic. There’s not much question about what it is, but we ought to get a smear and make a microscope slide check of it.”

“I’ve got a 1500-power instrument,” said Ken. “If that’s good enough you can use it.”

Hart nodded. “Get some sterile slides.”

Afterward, Smithers said, “We’ve got to get Jack Nelson first and find out how much anthrax vaccine he’s got in his store. Nobody else in town will have any, except maybe some of his customers who may have bought some lately. What about the college laboratories? Do they have any?”

“I don’t know,” said Professor Maddox. “We’ll have to contact Dr. Bintz for that.”

“Let’s get at it,” said Hart. “We’ve got to wake up the Mayor and the Council. The cattle committee will have to be there. Nelson and Bintz, too. We’ll find out how much vaccine we’ve got and decide what to do with it.”

Two hours later the men met in the Council chambers of City Hall. Because of the lack of heat, they retained their overcoats and sheepskin jackets. The incrusted snow on their boots did not even soften. In soberness and shock they listened to Dr. Smithers.

“Nobody grows up in a farming community without knowing what anthrax means,” he said. “We’ve got a total of twenty-eight hundred head of beef and dairy cattle in the valley, plus a couple of thousand sheep, and about a hundred horses.

“Jack Nelson’s stock of vaccine, plus what he thinks may be in the hands of his customers, plus some at the college is enough to treat about a thousand animals altogether. Those that aren’t treated will have to be slaughtered. If they prove to be uninfected they can be processed for meat storage.

“Some vaccine will have to be held in reserve, but if we don’t clean up the valley before next year’s calf crop we won’t stand a chance of increasing our herds. That’s the situation we’re up against, Gentlemen.”

Mayor Hilliard arose. “The only question seems to me to be which animals are of most worth to us. I say we should let all the sheep go. A cow or a horse is worth more than a sheep to us now.

“That leaves the question of the horses. Which is worth more to us: a horse or a cow? We can’t haul logs without horses, but we won’t need to worry about staying warm if we haven’t got food enough.”

Harry Mason of the fuel committee stood up immediately. “I say we’ve got to keep every horse we’ve got. It would be crazy to give any of them up. There aren’t enough now to haul the fuel we need.”

“A horse is a poor trade for a cow in these times,” protested the food committee’s chief, Paul Remington. “Every cow you let go means milk for two or three families. It means a calf for next year’s meat supply. We can freeze and still stay alive. We can’t starve and do the same thing. I say, let every horse in the valley go. Keep the cows and beef cattle.”

An instant hubbub arose, loudly protesting or approving these two extreme views. Mayor Hilliard pounded on the desk for order. “We’ve got to look at both sides of the question,” he said, when the confusion had died down. “I know there are some horses we can lose without much regret; they don’t haul as much as they eat. What Paul says, however, is true: Every horse we keep means trading it for a cow and the food a cow can provide.

“I think we need to keep some horses, but it ought to be the bare minimum. I’ve got an idea about this log hauling. Right now, and for a long time to come, we don’t need horses once the logs are on the road. It’s a downgrade all the way to town. When the road freezes hard we can coast a sled all the way if we rig a way to steer and brake it properly. There are only two bad curves coming out of the canyon, and I think we can figure a way to take care of them. Maybe a team at each one.

“This would leave most of the horses free to snake the logs out of the hills to the road. I’m for cutting the horses to twenty-five, selecting the best breeding stock we’ve got, and including the ones needed for emergency riding, such as the Sheriff has.”

For another hour it was argued back and forth, but in the end the Mayor’s plan was adopted. Then Dr. Aylesworth, who had not previously spoken during the whole meeting, arose quietly.

“I think there’s something we’re forgetting, Gentlemen,” he said. “Something we’ve forgotten all along. Now that we are faced with our most serious crisis yet, I suggest that you members of our city government pass a resolution setting aside the next Sabbath as a special day of prayer. Ask the ministers of all our denominations to co-operate in offering special prayer services for the safety of our animals, which we need so badly, and for the success of those who are working on College Hill and elsewhere to find a solution to this grave problem.”

Mayor Hilliard nodded approvingly. “We should have done it long ago,” he agreed. “If no one has any objections I will so declare as Dr. Aylesworth has suggested.” There were nods of approval from everyone in the room.

By dawn the next morning the crews were ready to begin the vaccination program. One by one, they examined the animals to make sure the best were saved. The rest were slaughtered, examined for signs of anthrax, and most were prepared for storage.

On Sunday, while the cattle crews still worked, Ken and his parents attended services in Dr. Aylesworth’s congregation. A solemnity was over the whole valley, and the only sound anywhere seemed to be the tolling of the bells in the churches.

The anthrax outbreak had seemed to the people of Mayfield one more, and perhaps a final, proof that their hope of survival was beyond all realization. Before, with severe rationing, it had seemed that they would need a miracle to get them through the winter. Now, with the brutally lessened supply of milk and breeding cattle, it seemed beyond the power of any miracle.

Dr. Aylesworth’s white mane behind the pulpit was like a symbol testifying that they never need give up hope as long as any desire for life was in them. In himself there seemed no doubt of their eventual salvation, and in his sermon he pleaded with them to maintain their strength and hope and faith.

In his prayer he asked, “Father, bless our cattle and our beasts of burden that this illness that has stricken them may be healed. Bless us that our hearts may not fail us in this time of trial, but teach us to bear our burdens that we may give thanks unto Thee when the day of our salvation doth come. Amen.”