The coral island
(Valia, the UK Lamplighter novel I thought you might mean was published in 1854, was written by Maria Susanna Cummins. I never found D.M Cornish's book by that name, so thank you. I'll keep an eye out for it.
And it gets worse. There is also a third novel called The lamplighter, an Australian publication from 2003, written by Anthony O'Neill and listed in both Amazon & Trove. 
It is the same sort of dilemma I also had with The Passage further up the thread, because not only is the 1930's Australian book of that name the same title as a more recent USA title, but the author of the Passage, Vance Palmer, is easily confused with Vance Packard, a famous USA author. Of course I've totally read that Australian one. Not necessarily by choice, unlike most of the Aussie titles I've been using lately.
)
)
)
)