Philip Pullman’s latest missal, La Belle Sauvage, once again features the boat-dwelling Gyptians. Rough and honourable, they emerge from the waterways of Brytain to help the heroine Lyra, before disappearing back to their watery world, one that runs through Lyra’s, but is separate and different from it. After a long weekend on the canals in the heart of Britain, I feel I have been drifting in Pullman’s wake.