I've never read it, but it sounds interesting. Can you give a more explicit synopsis?

Hmmm...well. Venice is the last city that anyone knows of that has not fallen to the Pharaoh's troops (the Pharaoh died long ago and was ressurected by his priests, so now he is even more powerful). But Venice's one defense, the Flowing Queen, who for centuries protected the canals, seems to have disappeared.... Joining up with a boy apprenticed to a rival merchant, Merle (the girl's name) soon finds herself in the posession of the trapped Flowing Queen--