Sir Frank Athelstane Swettenham (1850-1946) was a British colonial official among the Malays, and in 1898 came out with this collection, describing it in the preface as a series of letters by a friend, given to him after the friend’s death, to share as he pleased. A cynical observer might think this was Swettenham’s way of sharing his views and reminiscences in a wandering way without having to organize or take any responsibility for them.
The letters can be read here, but unfortunately there’s no mention of the cover designer in the book itself. There’s a juicy biography of Sir Frank here, and a swell painting of the author/”editor” by John Singer Sargent below. (By the way, Sargent’s copy of Unaddressed Letters is held by the Johns Hopkins Libraries.)