In Chesteron's play Magic a character often uses a phrase such as “as old Buffle used to say” or variations thereof. Is this, or used it to be, a common phrase? Does it have a specific meaning or is it just a foible of that character (the Duke)? The only connection I seem to find is with a character in Dickens's “Mrs. Lirriper's Legacy”, a Mr Buffle.
I believe the Duke, an amiable fathead if ever there was one, is referring to Georges Leclerc, comte de Buffon (usually called Buffon in English), a noted biologist. See, for example, this citation: