He regarded Mr. Cave's back with sullen distaste--would he never move away and set them free? Now he turned, his eye fell casually on the hut, he made as if to come closer but thought better of it. Andrew felt the muscles of his belly contract, and his fingers clench on the bar. A mocking-bird whistled from somewhere, and Mr. Cave grew still. It whistled again and he put his shoulders back and started to walk toward the sentry, crackling the twigs underfoot deliberately as he went as if he wanted the sentry to hear. The sentry heard and stiffened, musket to his shoulder. "Who goes there?" he challenged softly. Mr. Cave stopped just on the edge of the open ground. "Overseer Cave," he said in a flat voice, his bearish shoulders stooped. "Come out where I can look at you, overseer," said the sentry briskly, his eye along the barrel. Mr. Cave approached slowly. "It's all right, Jenkin," he said in a confidential voice, "I know your orders. They don't apply to me. I've a message for the Doctor." "Sorry, overseer," said the sentry, lowering his musket, "Have to wait till the sergeant makes rounds again. Strict orders--nobody to pass." "You can read, I suppose," said Mr. Cave with heavy sarcasm, coming nearer, "I have a pass. Dr. Gentian's signature." The sentry shook his head. "Don't know anything about passes," he said. "Show it to the sergeant," but he brought his musket down and leaned forward as if to inspect a paper. "But I'm in a hurry, I tell you," said Mr. Cave, very near him. Then, to Andrew's astonishment, the sentry continued to lean forward till he had passed his center of balance and, with a gasp, was falling as if he intended to embrace Mr. Cave in his outstretched arms. Mr. Cave caught him deftly and lowered him to the ground. "Well done, lass," he said in a whisper to the skirted shadow that had crept around the other corner of the storehouse and struck the sentry down from behind. He raised his voice a little. "Come on, boys," he called softly, and the night was suddenly populous with catlike shapes. One stooped over the fallen sentry--his hand glittered with something thin and bright--there was the chuck of a flat stone striking water on its edge, and a horrible, muffled coughing. "Sergeant of the Guard!" came a doleful howl from another quarter of the compass, "Sergeant of the Guard!" A musket shot clanged on the moonlight. Then events began to succeed each other far too rapidly for Andrew to keep track of them.