have dwindled until Four looked pale and thin-faced and wizened. "And, Four," Reba said automatically, "don't call your father 'Junior.' It sounds disrespectful." Reba was Four's mother and Junior's wife. On her own, she was a red-haired beauty with the loveliest figure this side of Antares. That Junior had won her was, to Grampa, the most hopeful thing he had ever noticed about the boy. "But everybody calls Junior 'Junior,'" Four complained. "Besides, Fred is Junior's father and Junior calls him 'Fred.'" "That's different," Reba said. Grampa was still waving his puzzle circuit indignantly. "See!" The pircuit was a flat box equipped with pushbuttons and thirteen slender openings in the top. One of the openings was lighted. "That landing made me push the wrong button and the dad-blasted thing beat me again." "Stop picking on Junior," Joyce said sharply. She was Junior's mother and Fred's wife, still slim and handsome as she approached sixty, but somehow ice water had replaced the warm blood in her veins. "I'm sure he did the best he could." "Anybody talks about gravitational pull," Grampa said, snorting, "deserves anything anybody could say about him. There's no such thing, Junior. You ought to know by now that gravitation is the effect of the curving of space-time around matter. Einstein proved that two hundred years ago." "Go back to your games, Grampa," Fred said impatiently. "We've got work to do." Grampa knitted his bushy, white eyebrows and petulantly pushed the last button on his pircuit. The last light went out. "You've got work to do, have you? Whose flivver do you think this is, anyhow?" "It belongs to all of us," Four said shrilly. "You gave us all a sixth share." "That's right, Four," Grampa muttered, "so I did. But whose money bought it?" "You bought it, Grampa," Fred said. "That's right! And who invented the gravity polarizer and the space flivver? Eh? Who made possible this gallivanting all over space?" "You, Grampa," Fred said.