Once, a long time ago, there were three little engines, who lived in their own little shed, on their own little railway. Of the three of them, Duke was the oldest and wisest, and he liked to keep the little engines in order. Duke also helped new engines and taught them what to do. Many engines came and went on the little railway, but Duke outlasted them all. One day, a big gray tank engine had arrived. Duke had told him to take some trucks to the slate mines. “Don't be late,” Duke had warned him, “That would never suit His Grace!” The engine just laughed, and puffed away with his trucks.