en he got away through the
window and left his gun behind him. That's how I read it; for nothing
else will fit the facts."

The sergeant picked up a card which lay beside the dead man on the
floor. The initials V.V. and under them the number 341 were rudely
scrawled in ink upon it.

"What's this?" he asked, holding it up.

Barker looked at it with curiosity. "I never noticed it before," he
said. "The murderer must have left it behind him."

"V.V.--341. I can make no sense of that."

The sergeant kept turning it over in his big fingers. "What's V.V.?
Somebody's initials, maybe. What have you got there, Dr. Wood?"

It was a good-sized hammer which had been lying on the rug in front of
the fireplace--a substantial, workmanlike hammer. Cecil Barker pointed
to a box of brass-headed nails upon the mantelpiece.

"Mr. Douglas was altering the pictures yesterday," he said. "I saw him
myself, standing upon that chair and fixing the big picture above it.
That accounts for the hammer."

"We'd best put it back on the rug where we found it," said the sergeant,
scratching his puzzled head in his perplexity. "It will want the best
brains in the force to get to the bottom of this thing. It will be a
London job before it is finished." He raised the hand lamp and walked
slowly round the room. "Hullo!" he cried, excitedly, drawing the window
curtain to one side. "What o'clock were those curtains drawn?"

"When the lamps were lit," said the butler. "It would be shortly after
four."

"Someone had been hiding here, sure enough." He held down the light, and
the marks of muddy boots were very visible in the corner. "I'm bound to
say this bears out your theory, Mr. Barker. It looks as if the man got
into the house after four when the curtains were drawn, and before six
when the bridge was raised. He slipped into this room, because it was
the first that he saw. There was no other place where he could hide,
so he popped in behind this curtain. That all seems clear enough. It
is likely that his main idea was to burgle the house; but Mr. Douglas
chanced to come upon him, so he murdered him and escaped."

"That's how I read it," said Barker. "But, I say, aren't we wasting
precious time? Couldn't we start out and scout the country before the
fellow gets away?"

The sergeant considered for a moment.

"There are no trains before six in the morning; so he can't get away
by rail. If he goes by road with his legs all dripping, it's odds tha