Merlo fired clumsily and the blue flare of the bullet was low on the guard tower, but the light wavered and swung away for an instant. It swung back, but the Martian had vanished in the darkness. Then it traversed once more to bathe the closing port in its glare. A stream of bullets clanged and clattered against the steel as they wrenched the locking lugs into place. Nick staggered to the control chair. Automatically his hand reached for the converter switches and found them on. The converters were already warmed, as though Harmon had been planning a solo get-away in case the battle went badly for his forces. Still only half realizing that it was the similarity to the fighter rockets of the War days that made the spaceship controls seem so familiar, Nick opened the fuel feeds to the main tubes and his hand hovered over the ignitor key. "Ready?" he asked. Susan threw herself into the acceleration cushions. "Blast it!" she urged. "Quick, before they turn a proton cannon on us!" Nick's finger hit the key and the world went black. His stomach was twisting in the agonies of acceleration cramps. His shoulder thumped and throbbed, and the gashes the barbs of the barrier had left on his body felt like lines of fire. Some sharp cornered object was wedged between his side and the seat belt, poking at his bruised ribs. Clumsily, his one usable hand lacerated in his struggle with the barrier, he fished it out. His hand failed to grasp it properly and the box of Gravinol slipped through his fingers and fell to the floor. He stared down at it, and there was longing in his look. In that little box was relief from pain. But other things too were in that box. Slavery, for instance. He looked a long time, then slowly shook his head. "Ease off the throttles," Susan spoke. "We're out." He did so, aiming the cross-hairs at the green star of Earth and coupling in the gyros. "It'll be hell back there without Gravinol," he reflected aloud. "You'll never know how bad it can be." Susan brought out the first aid kit and gently wiped the dirt and clotted blood from his wounded shoulder as he slumped in the pilot's seat. "A few will survive and be cured. The strong ones," she reminded him. "Ouch! That hurts!" he protested, and sat up suddenly as antiseptic stung in the wound. "You did, dear," she replied with feminine irrelevance.