"I will save my master," he cried, his eyes blazing maniacally. "I will save him yet!" Father Brown could do nothing but gaze after the boat as it struggled up-stream and pray that the old man might waken the little town in time. "A duel is bad enough," he muttered, rubbing up his rough dust-coloured hair, "but there's something wrong about this duel, even as a duel. I feel it in my bones. But what can it be?" As he stood staring at the water, a wavering mirror of sunset, he heard from the other end of the island garden a small but unmistakable sound—the cold concussion of steel. He turned his head. Away on the farthest cape or headland of the long islet, on a strip of turf beyond the last rank of roses, the duellists had already crossed swords. Evening above them was a dome of virgin