I just discovered this gem, a 1908 novella by G.K. Chesterton, thanks to a recommendation from Jed Berry when I had the pleasure of speaking to him recently ("The Debut of a Cycling Umbrellist," March 5, 2009). The prose is densely Victorian, as if just behind the page lurks a steam engine, spitting out the phrases. But like most of the best fiction, it establishes its parameters at the beginning and before long, you're used to them, you speak the book's language.
The Man Who Was Thursday clocks in (though I'm just at the beginning) somewhere between Edwardian/late Victorian flights of fancy of the more philosophical variety and a sort of whimsical chess game with pieces borrowed from The Wild Wild West and Scotland Yard. (I suspect that half-baked triangulation will change as I move through the book, but I don't want to wait till I'm halfway done to point out this book.) In any case–a most intriguing read, and highly recommended, especially for those who, like me, enjoy stories populated with a few London sunsets and Soctland Yard inspectors and know what jellied eels are.
ADDITIONAL:
Engrish.com unwittingly discovers the heart of some sort of conspiracy we probably don't want to know more about: