The problem with writing a book about trains is that it hands your critics a healthy arsenal of cheap metaphors to use in reviews (see also: Atlas Shrugged). Do we say that Railsea goes off the tracks a bit? That it doesn't really make it into station? Or indeed, that it never really gets up a good head of steam? Screw the puns. Let's just say it's not really up to par. This isn't to say that Railsea is bad, but it has a lot to live up to. Mieville has already written a better book about trains (Iron Council), a superior story about oceanfaring (The Scar), and a much more inventive YA novel (Un Lun Dun). Where does that leave Railsea? It's readable, even captivating at times, but ultimately a bit of a trifle.
Other readers have called this "Moby Dick with moles," but that's not quite true. Set on a planet where hunters, pirates, and scavengers roam an "ocean" of train tracks while avoiding dangerously-outsized ferrets, earwigs, and burrowing owls, Mieville does invoke Melville: train captains in this society each grow obsessed with a particular animal, including one who hunts a great white mole named Mocker-Jack. But these are just spice, thrown in as mood-setters. The vast majority of the book is actually about a moletrain doctor's assistant named Sham, who finds a memory card that leads to the end of the titular railsea, and kicks off a chase for the rumored riches located there.
Railsea is filled with clever authorial touches, like the use of the ampersand instead of "and" (there is a in-text reason) or an extended meditation on the ways that stories are themselves on rails, particularly in science fiction. Always respectful of genre, Mieville throws in passing references to Aubrey and Maturin, Robinson Crusoe, and Roadside Picnic (watch for the mention of a "Strugatski triskele"). These touches add interest to what is otherwise a pretty limp narrative: Sham spends most of his trip passively wandering up to more interesting stories, until the inevitable character growth moment. This is a book that's better as a critic than as a reader, but even there, it's not subtle: the layered, rich symbolism of Weavers and golems is missing, although I'll admit to enjoying the authorial asides that draw attention to the text's own lumpy pace.
Where Railsea redeems itself is in Mieville's writing, which is still (love it or hate it) an incredibly distinctive prose style, and its straight-faced embrace of the ridiculous. He gives only the slightest indication that his setting--with its savage naked mole rats, rail captains with mandatory artificial limbs, and carriages pulled by rhinocerii--is completely preposterous. Mieville has always written worlds that piled unlikelihood on improbability atop impossibility, but here he occassionally winks to us, such as this section on the theology of trees and railway ties:
Of all the philosophers' answers, three stand out as least unlikely.
— Wood & wood are, in fact, appearances notwithstanding, different things.
— Trees are creations of a devil that delights in confusing us.
— Trees are the ghosts of ties, their gnarled & twisted & dreamlike echoes born when parts of the railsea are damaged & destroyed. Transubstantiated matter.
All other suggestions are deeply eccentric. One of these three is most likely true. Which you believe is up to you.
All gripes about the book aside, I find that completely charming. This mischievious voice makes Railsea the kind of book that's almost begging to be read aloud. And if, in the end, the twists in this tall tale are a bit straighter than you might expect, I suspect it's still worth the price of the ticket.