Infernal devices - Philip Reeve

INFERNAL DEVICES is the third thrilling instalment in Philip Reeve's
brilliantly-imagined creation, the world of the Traction Era,
where mobile cities fight for survival in a post-apocalyptic fuure.
Tom and Hester's daughter, Wren, longs to escape the peace of static
Anchorage. She craves the dangerous adventures her parents once
had - and a charming submarine pirate is ready to take her to
sea. But the mysterious object that she steals for him ignites
conflict that will tear the whole world apart..
"Big, brave, brilliant" GUARDIAN
Philip Reeve has won the CILIP Carnegie Medal, the Guardian Children's
Fiction Prize, the Nestle Children's Book Prize and the Blue
Peter Book of the Year.