There's truly a lot to enjoy here, especially if you're a fan of philosophy and moles. 
 Sometimes together. No, no, scratch that. You can't separate the philosophy from the moles. 
 Every captain must have a philosophy to chase after, and truly, it DOESN'T REALLY MATTER if you're missing an arm or a leg, Okay? Just trust me on this. Don't go chopping off perfectly good appendages just because some bloody mole popped out of one of the seven layered seas and ruined my perfectly happy steampunk reverie. 
 This is vintage Mieville, in my opinion, or at least, this is the kind of Mieville I'll always associate with Mieville. It's the unabashedly weird, the hints of some truly spectacularly interesting worldbuilding, the use of small furry creatures, and the totally meta reimagining of classics, distilled into what could almost be a children's tale of adventure, including trains on the high seas, pirates, and One Huge Goal. 
 (Yes, Philosophy. Most philosophy comes with a (tail) to tell, and only good philosophy has a (tale) you can hold on to.) 
 Hell, that's my favorite part. 
 Unfortunately, there's a lot less philosophy than I really wanted, and some of the (tail) drags around a bit too much, so it's not quite as cohesive as I'd like. 
 Otherwise, it was clever and cute and I really wanted to like it more than I actually did. Much like most of Mieville's work, actually. I take my hat off. I bow respectfully to the sheer weight of imagination and word wrangling skill. 
 And then I wish the shape of the whole novel had been better. 
 It's worth reading. I just wish I could outright love it, too. There's so much promise.