y, and today I expect they thought their
visitation was over. But we have worked it as far as it will go. We
shall have to change our methods."

The inspector looked his question and Hunt continued:

"I think tomorrow I had better go out to the works and have a look over
these certificate blocks. But I wonder if it would be well for you to
come? Archer has seen you in that hotel lounge, and at all events he has
your description."

"I shall not go," Willis decided. "See you when you get back."

Hunt, after showing his credentials, was received with civility at
Messrs. Ackroyd & Holt's. When he had completed the usual examination
of their various apparatus he asked for certain books. He took them to a
desk, and sitting down, began to study the certificate blocks.

His first care was to compare the list of outward lorries which he
and Willis had made with the blocks for the same period. A short
investigation convinced him that here also everything was in order.
There was a certificate for every lorry which had passed out, and not
only so, but the number of the lorry, the day and hour at which it left
and the load were all correct so far as his observations had enabled him
to check them. It was clear that here also he had drawn blank, and for
the fiftieth time he wondered with a sort of rueful admiration how the
fraud was being worked.

He was idly turning over the leaves of the blocks, gazing vacantly at
the lines of writing while he pondered his problem when his attention
was attracted to a slight difference of color in the ink of an entry on
one of the blocks. The consignment was a mixed one, containing different
kinds of spirituous liquors. The lowest entry was for three twenty-five
gallon kegs of French brandy. This entry was slightly paler than the
remain order.

At first Hunt did not give the matter serious thought. The page had
evidently been blotted while the ink was wet, and the lower items should
therefore naturally be the fainter. But as he looked more closely he saw
that this explanation would not quite meet the case. It was true that
the lower two or three items above that of the brandy grew gradually
paler in proportion to their position down the sheet, and to this rule
Archer's signature at the bottom was no exception. In these Hunt could
trace the gradual fading of color due to the use of blotting paper.
But he now saw that this did not apply to the brandy entry. It was the
palest of all--paler even