The beginnings of "Treasure Island."

“I would sometimes unbend a little, joining the artist (so to speak) at the easel, and pass the afternoon with him in a generous emulation, making coloured drawings. On one of these occasions, I made the map of an island; it was elaborately and (I thought) beautifully coloured; the shape of it took my fancy beyond expression; it contained harbours that pleased me like sonnets; and with the unconsciousness of the predestined, I ticketed my performance “Treasure Island” . . . . As I paused on my map of “Treasure Island”, the future character of the book began to appear there visibly among imaginary woods . . . . The next thing I knew I had some papers before me and was writing out a list.”

That is Robert Louis Stevenson's account of the beginnings of Treasure Island. Source.