Again the pale violet of the molecular beams touched the rock--which was now bubbling lava. In an instant, the great mass of flaming incandescent rock was flying like a glowing meteor, up into the air. It shot up with terrific speed, broke up in mid-air, and fell back as a rain of red-hot stone. The bright rays died out, but the pale fingers of the molecular beams traced across the level ground. As they touched it, the solid soil spouted into the air like some vast fountain, to fall back as frost-covered powder. The rays that had swung a sun into destruction were at work! What chance had man, or the works of man against such? What mattered a tiny planet when those rays could hurl one mighty sun into another, to blaze up in an awful conflagration that would light up space for a million light years around with a mighty glare of light! As if by a giant plow, the valley was torn and rent in great streaks by the pale violet rays of the molecular force. Wade tore loose a giant boulder and sent it rocketing into the heavens. It came down with a terrific crash minutes later, to bury itself deep in the soil as it splintered into fragments. Suddenly the _Ancient Mariner_ was jerked violently again. Evidently undaunted by their display of power, the aliens' rays had gripped the Earthmen's ship again and were drawing it with terrific acceleration. But this time the ship was racing toward the city, caught by the beam of one of the low-built, sturdy buildings that housed the protective ray projectors. Again Arcot threw on the mighty power units that drove the ship, bracing them against the pull of the beam. "Wade! Use the molecular ray! Stop that beam!" Arcot ordered. The ship was stationary, quivering under the titanic forces that struggled for it. The enemy fleet raced toward them, trying to come to the aid of the men in the tower. The pale glow of the molecular beam reached out its ghostly finger and touched the heavy-walled ray projector building. There was a sudden flash of discharging energy, and the tower was hurled high in the air, leaving only a gaping hole in the ground. Instantly, with the collapse of the beam that held it, the _Ancient Mariner_ shot backward, away from the scene of the battle. Arcot snapped off the drive and turned on the invisibility apparatus. They hung motionless, silent and invisible in the air, awaiting developments. In close formation, one group of ships blocked the opening in the wall of rays that the removal of one projector building had caused. Three other ships went to investigate the wreck of the building that had fallen a mile away. The rest of the fleet circled the city, darting around, searching frantically for the invisible enemy, fully aware of the danger of collision. The unnerving tension of expecting it every second made them erratic and nervous to the _n_th degree. "They're sticking pretty close to home," said Arcot. "They don't seem to be too anxious to play with us."