can bet that Cayley knows that. Anyway, he'd bang on it,
and you wouldn't answer, and then what would he think?"

Bill was silent; crushed.

"Then I don't see how we're going to do it," he said, after deep
thought. "He'll obviously come to us just before he starts out, and that
doesn't give us time to get to the pond in front of him."

"Let's put ourselves in his place," said Antony, puffing slowly at his
pipe. "He's got the body, or whatever it is, in the passage. He won't
come up the stairs, carrying it in his arms, and look in at our doors to
see if we're awake. He'll have to make sure about us first, and then go
down for the body afterwards. So that gives us a little time."

"Y-yes," said Bill doubtfully. "We might just do it, but it'll be a bit
of a rush."

"But wait. When he's gone down to the passage and got the body, what
will he do next?"

"Come out again," said Bill helpfully.

"Yes; but which end?"

Bill sat up with a start.

"By Jove, you mean that he will go out at the far end by the
bowling-green?"

"Don't you think so? Just imagine him walking across the lawn in full
view of the house, at midnight, with a body in his arms. Think of
the awful feeling he would have in the back of the neck, wondering if
anybody, any restless sleeper, had chosen just that moment to wander
to the window and look out into the night. There's still plenty of
moonlight, Bill. Is he going to walk across the park in the moonlight,
with all those windows staring at him? Not if he can help it. But he
can get out by the bowling green, and then come to the pond without ever
being in sight of the house, at all."

"You're right. And that will just about give us time. Good. Now, what's
the next thing?"

"The next thing is to mark the exact place in the pond where he drops
whatever he drops."

"So that we can fish it out again."

"If we can see what it is, we shan't want to. The police can have a
go at it to-morrow. But if it's something we can't identify from a
distance, then we must try and get it out. To see whether it's worth
telling the police about."

"Y-yes," said Bill, wrinkling his forehead. "Of course, the trouble with
water is that one bit of it looks pretty much like the next bit. I don't
know if that had occurred to you.

"It had," smiled Antony. "Let's come and have a look at it."

They walked to the edge of the copse, and lay down there in silence,
looking at the pond beneath them.

"See anything?" sa