Herb had been sent home from school for swearing at a teacher. They’d phoned his father, and his father had said "What the ... Where did he learn that from?" Herb started walking home. Then he noticed something he’d never seen before. There was a sign as he walked past the gas works:
NO SMOKING. DANGER OF EXPLOSION.
Herb lit a cigarette and threw it over the fence. He carried on walking. That should teach the town a lesson.
Nothing happened.
Herb went back. That’s when it happened.