Part of an autograph letter signed to "Florence"

Novelist. Part of an autograph letter, 4.5 x 3.5 ins, probably 8vo when intact. Surviving text as follows: "34 De Vere Gdns,/ W./ Oct. 29th// Dear Florence./ The acquaintance that I have been [fragment of page concludes but crosswritten text continues as follows]" int) & believe the [...?]/[...?] faithfully yours/Henry James". On verso as follows: "3// al - Tinsley Bros. or V[?] R. Maxwell (Miss Braddon's.) I don't know [word underlined] any of these people, but" [fragment ends. A tantalising letter firstly for its recipient and secondly for his view of Tinsley, John Maxwell and Maxwell's wife, Miss Braddon. Tinsley and Maxwell were publishers who did not publish anything by James and who are apparently not mentioned in Tinsley's (unindexed) autobiography. James was an admirer of Miss Braddon and started reviewing her works in 1865. Perhaps he means a personal acquaintance by the word "know". I have found three Florences in Edel's edition of the Letters and his biography of James. I rule out Florence Bell since, in surviving letters, he writes to her as "Mrs Bell" not "Florence". There is also a Florence Wilkinson, but no letters are recorded (Edel indexes one as to her but in fact it was to Mary Wilkinson). I favour Florence Lockwood since she was an old enough friend (New York days 1875) to justify first name terms. James described her as "one of the big figures of one's experience". NO surviving letter to her has been recorded.