Anthony found the question very hard to determine. A matter of a yard or so made all the difference. But one point was made abundantly clear. It was quite possible that he had been mistaken in describing the light as occurring in the second room from the end. It might equally well have been the third .

Now who occupied the third room? Anthony was determined to find that out as soon as possible. Fortune favoured him. In the hall Tredwell had just set the massive silver urn in its place on the tea tray. Nobody else was there.

“Hullo, Tredwell,” said Anthony. “I wanted to ask you something. Who has the third room from the end on the West side? Over the Council Chamber, I mean.”

Tredwell reflected for a minute or two.

“That would be the American gentleman’s room, sir. Mr. Fish.”