He crossed over the road and there on a seat under the trees was a sailor like himself. Field did not assume to be asleep but was pulling at a short clay pipe. "Come and sit down, sir," he said. "I've just come. As I anticipated, I am being watched. But I managed to give my shadowers quite a wrong impression and I passed from the house, where I keep a few stock disguises, under their very noses. They imagine that they are following me up West by this time." "I am afraid all the trouble has been wasted," Berrington said irritably. "The birds have flown." "Indeed, sir. And who did you get that valuable piece of information from?" "From my friend the policeman that I told you about. The house is shut up for a few days and the authorities have been informed of the fact. I have been all around the house and it is as silent as the grave." "Well, that might be merely a blind, after all," Field said cheerfully. "When did they go?" "So far as I can gather from Macklin, they departed early this morning." Field chuckled but said nothing. A little while later there was a thud of heavy boots on the pavement, and Macklin and his sergeant came, together. The latter was about to say something but Field produced his card and the effect was instantaneous. "No, we don't want any assistance at all," the Scotland Yard official said. "All you can do is to go about your work as if nothing was taking place. You may notice something suspicious presently at No. 100, across the road, but you are to ignore it. You understand?" The sergeant nodded and touched his helmet; he understood perfectly well. The two passed on together and the sham sailors crossed the road. Very quietly Field proceeded to the back of the house. It was a little dark here, and he guided himself by pressing his fingers to the walls. Presently he stopped, and a low chuckle came from his lips. "Discovery the first, sir," he said. "Press your hand on the wall here. What do you notice?" But Berrington noticed nothing beyond the fact that the wall was quite warm. He said so, and the inspector chuckled once more. He seemed to be pleased about something. "That should tell you a story, sir," he said. "That house is supposed to be empty; nobody has been here since early this morning. If you will look up, you will see that the blank wall terminates in a high chimney--obviously the kitchen chimney. This wall is quite hot, it is the back of the kitchen fireplace--so obviously, if those people went early to-day there would be very little fire, in fact the range would have been out long ago. And what do we find? A hot wall that tells of a good fire all day, a good fire at this moment, or these bricks would have cooled down before now. If you listen you will hear the boiler gently simmering."