The Moonstone, Wilkie Collins
A comic butler and delusions about opium delusions; oh, and mysterious Indian gentleman jugglers, and what may be the original of the Jewel Stolen from the Head of a Foreign Idol cliché.
Collins is a headwater.
And, of course, it's available for free through the good graces of Project Gutenberg:
URL: http://digital.library.upenn.edu/webbin/gutbook/lookup?num=155
So wrote clew in
Fiction (19th c.).