Collingwood handed back the letter.

"Have you any idea to what that refers?" he asked.

"Well, I think I have--perhaps," answered Mrs. Mallathorpe. "Mr. Bartle
persuaded us to sell him some books--local books--which my late
brother-in-law had at his office in the mill. And since then he has been
very anxious to buy more local books and pamphlets about this
neighbourhood, and he had some which Mr. Bartle was very anxious indeed
to get hold of. I suppose he wanted to see me about that." Collingwood
made no remarks for the moment. He was wondering whether or not to tell
what Jabey Naylor had told him about this paper taken from the linen
pocket inside the _History of Barford_. But Mrs. Mallathorpe's ready
explanation had given him a new idea, and he rose from his chair.

"Thank you," he said. "I suppose that's it. You may think it odd that I
wanted to know what he'd written about, but as it was certainly the last
letter he wrote----"

"Oh, I'm quite sure it must have been that!" exclaimed Mrs. Mallathorpe.
"And as I am going into Barford this afternoon, in any case, I meant to
call at Mr. Bartle's. I'm sorry to hear of his death, poor old
gentleman! But he was very old indeed, wasn't he?"

"He was well over eighty," replied Collingwood. "Well, thank you
again--and good-bye--I have a motorcar waiting outside there, and I have
much to do in Barford when I get back."

The two young people accompanied Collingwood into the hall. And Harper