But recently I came across a new-to-me reference to what appears to be another very early publication. It comes in a letter from 1897 by Dunsany's uncle, Horace Plunkett (1854-1932), to Lady Betty Balfour. It reads:
See in the next Homestead, or September Pall Mall Magazine, p. 135, some lines by a nephew of mine, aetat 18. They are a happiness to me. If you knew the boy and his parents you would marvel at the product of his brain. He has a talent for chess and for upsetting things. He can draw a nightmare, but that he can write simple and rather musical English is a revelation which gladdens the avuncular heart. (quoted in Horace Plunkett: An Anglo-American Irishman (1949), by Margaret Digby, p. 152)We don't have the exact date of the letter (beyond 1897), and young Edward Plunkett would have turned 19 on 24th of July 1897. Since Horace give the page number of the September Pall Mall Magazine, it was evidently already published (perhaps in August), and The Irish Homestead was a weekly newspaper founded in 1895 by Horace Plunkett (and edited by others). So, evidently the next issue after this letter was written was to have something in it by "Edward Plunkett." This would likely be circa August to October 1897. I don't have easy access presently to The Irish Homestead to look for it. Perhaps someone reading this does, and can look for whatever it is and share the result, which I'd be happy to post here.