ent on:

"Now it happens that these Ackroyd & Holt people own some very large
licensed houses in Hull, and it is to them I imagine, that we should
first direct our attention."

"How do you propose to begin?"

"I think we must first find out how the Ferriby liquor is sent to these
houses. By the way, you probably know that already. You watched the
distillery during working hours, didn't you?"

The inspector admitted it.

"Did you see any lorries?"

"Any number; large blue machines. I noticed them going and coming in the
Hull direction loaded up with barrels."

Hunt seemed pleased.

"Good," he commented. "That's a beginning anyway. Our next step must be
to make sure that all these lorries carry certificates. We had better
begin tomorrow."

Willis did not quite see how the business was to be done, but he forbore
to ask questions, agreeing to fall in with his companion's arrangements.

These arrangements involved the departure from their hotel by taxi at
six o'clock the next morning. It was not fully light as they whirled out
along the Ferriby road, but the sky was clear and all the indications
pointed to a fine day.

They dismounted at the end of the lane leading to the works, and struck
off across the fields, finally taking up their position behind the same
thick hedge from which Willis had previously kept watch.

They spent the whole of that day, as well as of the next two, in their
hiding-place, and at the end of that time they had a complete list of
all lorries that entered or left the establishment during that period.
No vehicles other than blue lorries appeared, and Hunt expressed himself
as satisfied that if the smuggled brandy was not carried by them it must
go either by rail or at night.

"We can go into those other contingencies later if necessary," he said,
"but on the face of it I am inclined to back the lorries. They supply
the tied houses in Hull, which would seem the obvious places for the
brandy to go, and, besides, railway transit is too well looked after to
attract the gang. I think we'll follow this lorry business through first
on spec."

"I suppose you'll compare the certificate blocks with the list I made?"
Willis asked.

"Of course. That will show if all carry certificates. But I don't want
to do that yet. Before alarming them I want to examine the contents of a
few of the lorries. I think we might do that tomorrow."

The next morning, therefore, the two detectives again engaged a