My Talks With Dean Spanley by Lord Dunsany, 1936

A first person narrative of a man who meets Dean Spanley, an elder minister, at his club and discovers the Dean has a strong belief in Reincarnation. He begins to suspect the Dean has more than a belief, he may have actual memories of a past life and becomes determined to find out. Hoping to find scientific proof of the transmigration of souls if he can get Dean Spanley to talk, the narrator invites him to dinner. Believing in the adage "In vino veritas" he plies the Dean with wine. When Spanley drinks too much Imperial Tokay, a rare Hungarian wine, he starts talking about his former life as a country hound in the first person.
The narrator is astounded by the revelation and invites Spanley back several times hoping to discover scientific proof of reincarnation in Spanley's stories of his life as a dog. Each visit is harder since Spanley does not like to drink to excess, but each lapse reveals more of his canine existence.
An excellent short novel full of wonderful detail and dry understated humor. Recently made into a film called simply Dean Spanley starring Jeremy Northam and Sam Neill, this is a delightful tale.