aid at Mr.
Fielding's come out to the pillar-box. That was a few minutes after
eleven. I didn't see anybody at all the second time."

"Nobody at the judge's place--no taxi, or anything like that?"

"No, sir."

The taxi-cab turned swiftly into the shady avenue of Tanton Gardens,
where Sir Horace Fewbanks lived, and in a few moments pulled up outside
of Riversbrook. The house stood a long way back from the road in its own
grounds. Inspector Seldon and Flack passed rapidly through the grounds
and reached the front door of the mansion. There was nobody about; the
place seemed deserted, and the blinds were down on the ground-floor
windows. Inspector Seldon knocked loudly at the front door with the big,
old-fashioned brass knocker, and rang the bell. He listened intently for
a response, but no sound followed except the sharp note of the electric
bell as Flack rang it again while Inspector Seldon bent down with his ear
at the keyhole. Then the inspector stepped back and regarded the house
keenly for a moment or two.

"Put your finger on that bell and keep on ringing it, Flack," he said
suddenly. "I see that some of the blinds are down, but there's one on the
first floor which is partly up. It looks as though the house had been
shut up and somebody had come back unexpectedly."

"Perhaps it's Hill, the butler," said Flack.

"If he's inside he ought to answer the bell. But keep on ringing while I
knock again."

The heavy brass knocker again reverberated on the thick oak door, and
Inspector Seldon placed his ear against the keyhole to ascertain if any
sound was to be heard.

"Take your finger off that bell, Flack," he commanded. "I cannot hear
whether anybody is coming or not." He remained in a listening attitude
for half a minute and then plied the knocker again. Again he listened for
footsteps within the house. "Ring again, Flack. Keep on ringing while I
go round the house to see if there is any way I can get in. I may have to
break a window. Don't move from here."

Inspector Seldon went quickly round the side of the house, trying the
windows as he went. Towards the rear of the house, on the west side, he
came across a curious abutment of masonry jutting out squarely from the
wall. On the other side of this abutment, which gave the house something
of an unfinished appearance, were three French windows close together.
The blinds of these windows were closely drawn, but the inspector's keen
eye detected that one of the