Lady Sybil had reason to notice the representative of His Majesty's forces, and herself informed him severely that smoking was not allowed, and the man had put his cigarette under his heel with an apology and had walked out of the building. When Lady Sybil and her guest had entered her car and were driven away to Mill Hall, the soldier had been loitering near the entrance, and a few minutes later he was following the party in a taxi-cab which had been waiting at his order for the past two hours. The taxi did not turn in at the stone-pillared gates of the Hall, but continued some distance beyond, when the soldier alighted and, turning back, walked boldly through the main entrance and passed up the drive. It was dusk by now, and nobody challenged him. He made a reconnaissance of the house and found the dining-room without any difficulty. The blinds were up and the servants were setting the table. Then he passed round to the wing of the building and discovered the library. He actually went into that room, because it was one of Lady Sybil's standing orders that the library should be "aired" and that the scent of Mr. Crotin's atrocious tobacco should be cleared. He sniffed the stale fragrance and was satisfied that this was a room which was lived in. If there was any real, confidential talk between the two men, it would be here, he thought, and looked round for a likely place of concealment. The room was innocent of cupboards. Only a big settee drawn diagonally across a corner of the room promised cover, and that looked too dangerous. If anybody sat there and by chance dropped something--a pipe or an ash-tray---- He walked back to the terrace to take his bearings in case he had to make a rapid exit. He looked round and then dropped suddenly to the cover of the balustrade, for he had seen a dark figure moving across the lawn, and it was coming straight for the terrace. He slipped back into the room and as he did so he heard a step in the passage without. He stepped lightly over to the settee and crouched down. It was evidently a servant, for he heard the French windows closed and the clang of the shutters. They were evidently very ordinary folding-shutters, fastened with an old-fashioned steel bar--he made a mental note of this. Then he heard the swish of the curtain-rings upon the brass pole as the curtains were drawn. A dim light was switched on, somebody poked the fire, and then the light was put out and the door closed softly. The intruder did some rapid thinking. He crossed to the nearest of the windows, noiselessly opened the shutters and pushed them back to the position in which they stood when not in use. Then he unlatched the window and left it, hoping that it would not blow open and betray him. This done, he again pulled the heavy curtains across and returned to his place of concealment. That was to be the way out for him if the necessity for a rapid retreat should arise.