The Gap in the Curtain by John Buchan

Then in January a little thing happened which had momentous consequences.

He picked up a cheap lot of books at a sale in the Midlands, and one of these was a copy of a little-known political poem of Thomas Gray, called, I think, The Candidate. It was printed in the familiar Caslon type of the Strawberry Hill press, and it had on the fly-leaf a long inscription to a certain Theophilus Tallis, in which comment was made on the poet and his work. The inscription was signed "HW," and on the inside of the cover was the armorial bookplate of Tallis of Libanus Hall. If this inscription were genuine, here was an "association" book of a high order. Reggie compared it with many specimens of Horace Walpole's handwriting, with the general style of which it seemed to agree. Could he establish the identity of Theophilus Tallis, and ascertain that he had been a friend of Walpole's, the authenticity would be complete. Then he remembered the man he had met at Leriot. His name was Tallis, and he had a place on the Welsh border. Reggie had scribbled down his club address, so he wrote to him there and asked him for information. In a day or two a reply came from Libanus Hall. The Theophilus in question was his great-grandfather, said the writer, and doubtless the book had strayed from his library. Such things often happened -- an undergraduate would carry off a volume to Oxford and forget about it, or a guest would borrow and fail to return. The old Theophilus had left many papers which had never been examined, but in which the connection with Walpole could no doubt be traced. Let Reggie pay him a visit, for there were many things in his library to interest him.