The comet was setting earlier now, so that its unnatural light disappeared almost as soon as the sun set below the horizon. In the short period of twilight, tension grew in the city. Everything possible had been done to mount defenses. An attack had been promised if the nomad emissaries did not return. Now the time had come. Darkness fell with no sign of activity in any direction. It seemed unreasonable that any kind of night attack would be launched, but Hilliard and Johnson warned their men not to relax their vigilance. The pace of preparatory activity continued. Blankets, clothing and food were brought to the men who waited along the defense perimeter. Medical arrangements were perfected as much as possible. Ken and his father made their quarters in another room of the building where Dr. Adams' office was. There was no heat, of course, but they had brought sleeping bags which were unrolled on the floor. After the sandwiches were gone their rations were canned soup, to be eaten directly from the can without being heated. Maria was quartered elsewhere in the building with some of the women who were directing the nurses' activities. Through the windows could be seen the campfires which Johnson had permitted to be built at the guard posts. Each had a wall of snow ready to be pushed upon it in case of any sign of attack. "We'd better get some sleep," Professor Maddox said finally to Ken. "They'll take care of anything that's going to happen out there tonight. We may have a rough day tomorrow." Ken agreed, although he did not feel like sleeping. After hours, it seemed, of thrashing restlessly he dozed off. He thought it was dawn when he opened his eyes again to the faint, red glow reflected on the walls of the room. He was unaware for a moment of where he was. Then he saw the glow was flickering. He scrambled to his feet and ran to the window. In the distance the glow of burning houses lit the landscape. The rapid crack of rifle fire came faintly to his ears. Professor Maddox was beside him. "How could they do it?" Ken exclaimed. "How could they get through our lines and set fire to the houses?" On the southern sector of the defense line Sheriff Johnson's men crouched behind their improvised defenses. The glow of the fire blinded them as they attempted to pierce the darkness from which the attack was coming. From a half-dozen different points fireballs were being lobbed out of the darkness. Ineffective on the snow-laden roofs, many others crashed through the windows and rolled on the floors inside. Such targets became flaming infernos within minutes. They were all unoccupied because the inhabitants had been moved closer to the center of town for protection.