Pitt Street in Wellington runs just below the crest of a ridge. It is steep. When you look up to the houses, you don’t see much more than roofs. To reach the front gates you take paths that angle up the ten-foot clay bank that was cut when the road was made. The land seems less stable than the timber-framed houses that sit like ships on a sea of clay and rotten rock that after a week of rain slides below them in slow motion. In the old days, after several wet weeks there would be landslips in the cuttings that took the tramlines down to the promontory where the line comes into the open at a point on the fault scarp (it shows on the map as a ruled line along the west side of Wellington Harbour). You are still high up when you emerge from the cutting: it was (and is) a wonderful grandstand. The land feels eager to be eroded all over New Zealand. Charles Andrew Cotton, a local pioneer of geomorphology could illustrate most generalities of what erosion does to landforms with native examples.

LRB 1 December 2011 | PDF Download