The hard-riding nomad cavalry bore down on the defense line. They did not break into a circling column as before, I but began forming an advancing line. When they were 75 yards away, Sykes ordered his men to begin firing.

The nomads were already shooting, and what their emissary had said was true: these men were expert shots, even from horseback. Sykes heard the bullets careening off the sloping face of the barricade. Two of his men were down already.

He leveled his police pistol and fired steadily into the oncoming ranks. He thought they were going to try to jump the fence this time, and he braced for the shock. To his dismay, he now saw that a perfectly clear space for their landing had been left between his own position and the adjacent barricade.

Suddenly the line of attackers swerved to the left just a few feet from the wire. The defending fire was furious, and for a moment Sykes thought they were going to turn the line back. Then several of the nomads raised their arms and hurled dark, small objects toward the barrier. Sykes recognized them even while they were in the air. Grenades.

He shouted to his men and they flattened behind the barricade. Six explosions thundered almost simultaneously. Mud and rocks sprayed into the air and fell back in a furious rain upon the defenders.

Cautiously, Sykes lifted himself from the ground and got a glimpse of the scene once more. A hundred feet of barbed-wire fence had disappeared in a tangle of shattered posts and hanging coils. Through the opening, the nomads poured over the barricades in the midst of Sykes' men. Smashing hoofs landed almost upon him but for his frantic rolling and twisting out of their path. Gunfire was a continuous blasting wave. Sykes thought he heard above it the sound of Johnson's voice roaring commands to the retreating men.

It sounded like he was saying, "Close up! Close up!" but Sykes never knew for sure. An enormous explosion seemed to come from nowhere and thunder directly in front of him. The day darkened suddenly and he felt himself losing all control of his own being. He wondered if a cloud had crossed the sun, but almost at the same time he ceased to be concerned about the question at all.

The first of the wounded came in slowly, borne by stretcher bearers on foot who had literally dragged their charges through the lines of invading horsemen. Ken directed their assignment to the hospital-houses. He had always believed he could take a scene like this in his stride, but now he felt he must keep moving constantly to keep from becoming violently sick.

Overhead, a pall of smoke surged again, blotting out, partly, the comet's light. More houses had been fired by the invaders. The sound of crackling flames mingled with the thunder of hoofs and the roll of rifle fire.

Surely it wouldn't be possible, Ken thought, for such a charge to succeed unless it were backed by strong infantry. He moved into one of the houses and directed the placement of the severely wounded man brought up now by the bearers. As they left, he looked down at the stained and bloody face. A nurse was already at work cutting away the matted clothing from the wound.

Ken exclaimed loudly before he realized what he was saying. "Mr. Harris! Mr. Harris—you shouldn't have been out there!"

The man opened his eyes slowly against the terrible pain. He smiled in recognition. It was Mr. Harris, the principal of Mayfield High School; the one Ken had attended. He was an old man—at least fifty—much too old to have been at the barricade with a rifle.

"You shouldn't have been out there," Ken repeated. Mr. Harris seemed to have difficulty in seeing him.

"Ken," he said slowly. "It's Ken Maddox, isn't it? Everybody has to do something. It seemed like this was the best thing I could do. No school to teach. No school for a long time."

His voice wavered as he began to ramble. "I guess that makes all the students happy. No school all winter long. I always dreamed of Mayfield being a school where they would be glad to come, whose opening in the fall would be welcomed and closing in the spring would be regretted. I never got that far, I guess.

"I didn't do a really bad job, did I, Ken? Mayfield is a pretty good school, isn't it?"

"Mayfield is a swell school, Mr. Harris," said Ken. "It'll be the best day ever when Mayfield opens up again."

"Yes ... when school opens again," Mr. Harris said, and then he was still.

The nurse felt his pulse and regretfully drew the sheet up to cover his face. "I'm sorry," she said to Ken.

Blindly, he turned and went out to the porch. Mr. Harris, he thought, the little bald-headed man they'd laughed at so often with schoolboy cruelty. He had wanted to make Mayfield a good school, so students would be glad to attend.

He'd done that—almost. Mayfield was a good school.

Ken looked at the rolling clouds of black smoke in the sky. The gunfire seemed less steady now. Suddenly he was running furiously and with all his strength. He turned down Main Street and headed south. He ran until he caught sight of the first nomad he had seen since the events in the Mayor's Council chamber.

The enemy had stopped his horse, rearing high, while he hurled some kind of incendiary through the window of a house. It exploded inside and billows of flame and smoke poured out. A heart-tight pain gripped Ken. He looked wildly about and saw a fragment of brick lying beside a demolished house nearby.

He snatched up the missile and wound up as if pitching one straight over the corner of the plate. The horseman saw the motion of his arm and tried to whirl, but he was too late. The brickbat caught him at the side of the head and he dropped to the snow without a sound. Ken ran forward and caught up the nomad's rifle and ammunition belt. The horse had fled in panic.

Without a backward glance Ken raced on down the street toward the dwindling sound of battle. The invaders were retreating, streaming from all directions toward the break in the barrier, firing steadily as they came. The defenders were trying to block the escape.

Ken dropped behind a barricade next to an older man he didn't know. He searched for an opening and waited for a rider to cross his sights; then he squeezed the trigger and the man fell. When he looked up again the last of the invaders were gone. Only half of those who had come up to the attack were leaving it.

The men around Ken slowly relaxed their terrible tension. From some lying prone there were cries of pain. Those who could stand did so and revealed their drawn faces to one another.

Teams of the medical group began moving again. A horse-drawn wagon was brought up that had been fitted with boards across the sides so that two layers of wounded men could be carried at once.

Ken heard sudden hoofbeats behind and turned. Sheriff Johnson rode up and surveyed the scene. His eye caught Ken's figure standing in the midst of it, rifle in hand, the captured ammunition belt draped over his shoulder.

"You!" White anger was on Johnson's face. "You were ordered to stay out of the frontline!" he thundered. "Any other man would be court-martialed for such disobedience. Get back where you belong and don't show your face in this area again. I'll jail you for the rest of the fighting if you disobey again!"

Half-ashamed, but half only, for his impulsive action, Ken turned and moved down the street.

"Leave that gun here!" the Sheriff commanded harshly.

Ken gave it to the nearest soldier. He took off the ammunition belt and handed it over too, then resumed his course. He should not have done it, he told himself, but he felt better for it. He felt he had paid a little of his debt to Mr. Harris.

When he reached the hospital center he told his father.

"It wasn't a good thing," said Professor Maddox gently, "but maybe it was something that had to be done."

Throughout the day they continued to bring in the wounded and the dead. There seemed to be an incredible number, but the invaders had suffered heavily, too. Half their force had been lost. A dozen fine horses had been captured, which were a considerable prize.

There was speculation as to why the nomads chose to attack in this manner. They had done great damage, it was true, yet the attack had not had a chance of being decisive in spite of their insane persistence.

Hilliard and Johnson held a staff meeting that afternoon while a sharp watch was kept for further attack. They considered that they had done very well so far. The chief worries were the grenades and incendiaries, which the nomads seemed to have in large quantity.

Toward evening, Johnson asked for two volunteers to go out as scouts to try to reach the top of Lincoln's Peak, west of town, to spot the camp of the nomads and scout their activities. A pair of volunteers was chosen from the many who offered. On two of the best of the nomads' horses, they made their way across the frozen plain and up the small ravine leading to the ridge. Observers watched until they were out of sight in the ravine.

It was agreed the two would return by 6 o'clock. At 5 there was the faint sound of gunfire from somewhere in the hills. The scouts did not return at the appointed time. They did not return at all.

Night came, and word spread among the townspeople of the disappearance of the two scouts. Anxiety increased as it became apparent they were under close surveillance by the enemy. Perhaps it was the intention of the nomads to wear them down with a winter-long siege of attack after attack, until they no longer had the ability or strength to fight.

Hilliard and Johnson doubted this. The nomads were far less equipped for such a siege than Mayfield was.

Maria continued to return to the radio shack in the evening to maintain the schedule with the network. She reported the plight of Mayfield to the other stations. From across the country came the fervent best wishes of those who heard her. Wishes were all they could offer.

The scientists were particularly anguished because they considered the Maddox-Larsen group among the most likely to crack the barrier that kept them from conquest of the comet dust. "Our prayers are with you," the Pasadena group said.

They sent a new report and Maria typed it and showed it to Professor Maddox that evening. He scanned it and put the pages in his coat pocket as he glanced out the window toward College Hill.

"It seems like ages," he said. "I wonder if we'll ever get back up there."

The next attack came well before dawn. Sheriff Johnson was among the first to be aware of it. The thunder of seemingly countless horses' hoofs was heard faintly out of the south and he put his glasses to his eyes. The nomads were a black patch against the snow.

"How many horses have they got?" he exclaimed to the patrolman beside him. This was Ernest Parkin, one of his best officers.

"I'd say there must be at least a hundred of them," said Parkin in awe. "They must have been gathering horses for weeks."

"Feed," said Johnson, "for themselves and the animals—they may be rabble and savages, but they've had genius of leadership."

Behind shelter, they waited for the blow. All orders had already been given. Only the general alarm was sounded now. It had been expected that the previous pattern of attack would be repeated. The defenders had been moved back from the barbed wire. They fired slowly and methodically with a splendidly efficient barrage as the nomads swung out of the night to blast with their grenades at the reconstructed fence.

The way opened and they plunged in, the defenders closing behind and retreating to the other side of their barricades.

Ken paced restlessly as he heard the shooting. "I'm going up on the roof," he told his father. "There can't be any objection to that."

"I guess not. I'll call you when we need you."

Ken climbed the stairs of the 6-story building, which was the highest in Mayfield. He came out on the frozen surface of the roof and looked into the distance. The mounted invaders were circling like Indians about several blocks of houses, firing steadily at the defenders and hurling incendiaries at the houses.

Then, as Ken turned his eyes to the northern end of the valley, he felt as if the whole world had suddenly fallen to pieces in the dim, morning light.

On foot, a vast host of the invaders moved toward the northern defenses of the town. Instantly, he understood their strategy. While their small parties of mounted attackers had pressed the southern defenses, giving the impression they intended to make their major approach there, the bulk of their forces had marched entirely around Lincoln's Peak and come upon the northern boundary at night. That was why the peak had been so heavily guarded against the scouts.

It had been a march of over 40 miles to by-pass the valley. Now, however, the nomads were in a position to achieve their goal. The bulk of the town's defense was concentrated in the south. Little stood in the way of the horde advancing from the north.

His heart sickened as he saw them rip through the barbed-wire enclosure. The poorly manned defense posts seemed almost non-existent. Only a scattering of shots was thrown at the invaders.

From somewhere, a warning siren sounded, the agreed-upon signal to indicate invasion in that sector. It was far too late for that, Ken thought. The horde was already in the streets, fanning out, dispersing in the deserted streets.

Ken started for the doorway leading from the roof. His responsibility to College Hill was gone now. Every man in the valley was fighting for his own life. If that battle were lost, College Hill would be only an empty symbol, where ghosts were housed, as in Berkeley, as in Chicago, as in a thousand centers of learning the world around.

With his hand on the latch of the door he paused at a new sound that broke upon the air. An incredible barrage of firing was occurring along northern Main Street near 12th Avenue. He put the fieldglasses to his eyes again and watched the scattering nomads seeking cover. Dozens of them lay where they fell headlong in the streets.

Ken strained his eyes to see where the defense had come from. It was centered in the houses and buildings that lined the streets, and on their rooftops. He could see the ant-sized outlines of figures on those roofs. For a moment he failed to understand. Then he felt a choking sensation in his throat.

In a desperate gamble, Johnson and Hilliard had anticipated this move and prepared for it as best they could. They had allowed the main body of the attackers to enter the town itself and had deployed the majority of their guns to ring them about, while offering only token defense on the south.

This was it. The battle would be fought here and now, in the streets of Mayfield, and before the day was over it would be known whether the city would continue its struggle to live or whether it would become another Berkeley.