"He's as puzzled as the rest of us," said Sir Lyster in response. "He's making enquiries through Department Z." There was the merest suggestion of patronage in Sir Lyster's voice at the mention of Department Z. Sir Bridgman lit a cigarette, then after a short silence Sir Lyster said tentatively: "I suppose it isn't the Americans?" "Impossible," said Sir Bridgman. "You can't base ships on ether, and we were bound to know, besides frankness is their strong point. They are almost aggressively open," he added. "I----" began Sir Lyster, then paused. "It's damned funny," murmured Sir Bridgman for the third time. "Well, I must buzz off," he added, rising. "I shall see you at L.J.'s this afternoon." "It's a conference, I think," said Sir Lyster. "Walton is to tell us what has been discovered." Again there was the note of patronage in his voice. "Well," said Sir Bridgman, "I'll try and prevent it spoiling my lunch," and he stretched his big frame lazily. "By the way," he remarked, turning to Sir Lyster, "did you see about that convoy a hundred miles off its course, bleating like a lost goat to know where it was?" "It might have been very serious," said Sir Lyster gravely. "Oh! the luck of the navy," laughed Sir Bridgman. "We have to do it all, even teach the other fellows their job. Mark it, Grayne, we shall take over the whole blessed country before we've finished, then perhaps they'll raise our screws," and with that he left the room. Two minutes later his cheery laugh was heard outside again as he enquired of Mr. Blair if it were true that he was going to double the reward for the discovery of John Dene. A moment later he rejoined Sir Lyster and Admiral Heyworth. "I forgot about that flying-boat business," he said, and soon the three were engaged in a technical discussion. For more than three months Mr. Blair had known peace. He had been able to walk leisurely across St. James's Park from his chambers in St. Mary's Mansions, pause for a moment to look at the pelicans, dwell upon the memory of past social engagements and anticipate those to come, receive the salute of the policeman at the door of the Admiralty and the respectful bows of the attendants within and walk up the stairs and along the corridors to his room, conscious that in his heart was an abiding peace.