RLS’s letter sending the MS of Jekyll & Hyde to Longman does not appear to have survived, but Charles Longman, the publisher, acknowledged it on 31 October 1885. It was recorded by Andrew Lang in Athenaeum of 9 February 1895, when quoting this extract from RLS’s reply.
[As usual, for correct and critical edition of this letter, see Mehew 5, 1486.]
To Charles Longman [quoted by A. Lang in Athenaeum, 9 Feb 1895]
[Skerryvore, ? 1 November 1885]
It may interest you to know that the main incident occurred in a nightmare: indigestion has its uses.
I woke up, and before I went to sleep again, the story was complete.