I liked Leviathan much better than I liked Westerfield's Pretties/Uglies. Possibly because I liked (or could stand) the protagonists Alek and Deryn much more than I ever liked Tally. This book has good pacing, decent dialog, and a very good plot.

The part I struggled with is that I'm not sure he has a very good grounding in biology or physics. There are some authors who can blithely and believably write about technology they don't understand. However, Westerfeld is no Anthony Burgess, nor is he (sadly) a Neal Stephenson. He obviously tried, so I owe him credit for that. Possibly it's only because my background is in biology and I've had to endure rants and screeds about how anything so large as a dragon couldn't possibly fly. Or maybe the main problem is my lack of grounding in physics. Maybe you could inflate a whale body full enough of hydrogen that it floats. (Query: Why hydrogen and not helium? Has the Hindenburg not happened?) For the biology side of things, I'm very dubious that you could genetically engineer creatures like those in this book only knowing enough about DNA to call it "life strands" and not know about genes and base pairs. But perhaps I'm not giving the Steampunk Victorians enough credit. (Or maybe it did take years and years and years and that just wasn't emphasized. Though it can't have taken that long if Darwin's granddaughter is still a fairly young woman).

However, leaving the science aside, this was a very engaging steampunk novel. The divisions and differences between the Clankers and the Darwinists are interesting and engaging. The characters are fairly well drawn and believable. (I loved Deryn's pride in her satisfyingly clompy boots). Though both protagonists seemed younger than their supposed age. Deryn and Alek act (and seem to think) closer to 12 or 13 than 15 or 16. At times the book veered a little too close to Afterschool-Special-Zone (maybe the best solution is a mix of our two extreme views instead of one or the other being right!) But even that was over very quickly. Very fast-paced, interesting, and thought-provoking. I was particularly interested in the intimations that the Leviathan was sentient, as the main thing that bothered me about the Darwinist creations was the mixing of creatures with completely different life history strategies. It seems to me that in anything approaching a sentient creature, this would cause confusion.

I thoroughly enjoyed the illustrations, and very much appreciated Westerfeld taking time at the end to spell out where it differed from reality; I think that's a great way to get teens interested in history.

I'm looking forward to the next one. I can't wait to find out hatches out of the eggs. I'm hoping for dinosaurs.