nder the wharf,
on which was a pump. The only difference was in the connection of the
pipes. At Ferriby the pump conveyed from the wharf to the tun, here
it was from the tun to the wharf. The pipe from the garage came down
through the ceiling and ran direct into the tun.

The two men walked down the passage towards the river. Here also the
arrangement was the same as at Ferriby, and they remained only long
enough for Willis to point out to the Frenchman how the loading
apparatus was worked.

"Well," said the former, as they returned to the office, "that's not so
bad for one day. I suppose it's all we can do here. If we can learn as
much at that distillery we shall soon have all we want."

Laroche pointed to a chair.

"Sit down a moment," he invited. "I have been thinking over that plan
we discussed in the train, of searching the distillery at night, and
I don't like it. There are too many people about, and we are nearly
certain to be seen. It's quite different from working a place like
this."

"Quite," Willis answered rather testily. "I don't like it either, but
what can we do?"

"I'll tell you what I should do." Laroche leaned forward and checked his
points on his fingers. "That lorry had just been unloaded. It's empty
now, and if our theory is correct it will be taken to the distillery
tomorrow and left there over-night to be filled up again. Isn't that
so?"

Willis nodded impatiently and the other went on:

"Now, it is clear that no one can fill up that tank without leaving
finger-prints on the pipe connections in that secret box. Suppose we
clean those surfaces now, and suppose we come back here the night after
tomorrow, before the man here unloads, we could get the prints of the
person who filled up in the distillery."

"Well," Willis asked sharply, "and how would that help us?"

"This way. Tomorrow you will be an English distiller with a forest you
could get cheap near your works. You have an idea of running your stills
on wood fires. You naturally call to see how M. Raymond does it, and you
get shown over his works. You have prepared a plan of your proposals.
You hand it to him when he can't put it down on a desk. He holds it
between his fingers and thumb, and eventually returns it to you. You
go home and use powder. You have his finger-prints. You compare the two
sets."

Willis was impressed. The plan was simple, and it promised to gain for
them all the information they required without recourse t