ey had met.

"I wanted to give you the last report about Milburgh."

Milburgh again! All conversation, all thought, all clues led to that
mystery man. But what Whiteside had to tell was not especially thrilling.
Milburgh had been shadowed day and night, and the record of his doings
was a very prosaic one.

But it is out of prosaic happenings that big clues are born.

"I don't know how Milburgh expects the inquiry into Lyne's accounts will
go," said Whiteside, "but he is evidently connected, or expects to be
connected, with some other business."

"What makes you say that?" asked Tarling.

"Well," replied Whiteside, "he has been buying ledgers," and Tarling
laughed.

"That doesn't seem to be a very offensive proceeding," he said
good-humouredly. "What sort of ledgers?"

"Those heavy things which are used in big offices. You know, the sort of
thing that it takes one man all his time to lift. He bought three at
Roebuck's, in City Road, and took them to his house by taxi. Now my
theory," said Whiteside earnestly, "is that this fellow is no ordinary
criminal, if he is a criminal at all. It may be that he has been keeping
a duplicate set of books."

"That is unlikely," interrupted Tarling, "and I say this with due respect
for your judgment, Whiteside. It would want to be something more than an
ordinary criminal to carry all the details of Lyne's mammoth business in
his head, and it is more than possible that your first theory was right,
namely, that he contemplates either going with another firm, or starting
a new business of his own. The second supposition is more likely. Anyway,
it is no crime to own a ledger, or even three. By-the-way, when did he
buy these books?"

"Yesterday," said Whiteside, "early in the morning, before Lyne's opened.
How did your interview with Miss Rider go off?"

Tarling shrugged his shoulders. He felt a strange reluctance to discuss
the girl with the police officer, and realised just how big a fool he was
in allowing her sweetness to drug him.

"I am convinced that, whoever she may suspect, she knows nothing of the
murder," he said shortly.

"Then she _does_ suspect somebody?"

Tarling nodded.

"Who?"

Again Tarling hesitated.

"I think she suspects Milburgh," he said.

He put his hand in the inside of his jacket and took out a pocket case,
opened it, and drew forth the two cards bearing the finger impressions he
had taken of Odette Rider. It required more than an ordinary ef