Here is the map used by Charles Brasch in his hiking days, a Lands and Survey Department map of the Otago Peninsula published in 1942. Its folds divide it into 24 tattered squares, held together by a fragile muslin backing. The paper is creamy and brittle.
The city and the coastal area take up the left hand side of the map, the right hand side being mostly sea of a southern blue. A fine purple grid is superimposed on the landscape, which you may reach by slipping through the one-dimensional map as if it were the surface of a mirror.
Charles and Rodney are standing on the spine of the peninsula, facing north. Rodney is puffing and his eyes are bright. In one hand he has a stout stick and in the other the map of Charles Brasch. Charles is tall and thin. He has bushy eyebrows. He is dressed in khaki shorts and shirt. In his rucksack he carries a compass, a pair of binoculars, a water bottle, a green pullover, a battered Auden, two notebooks and several pencils.
Running due south, the centre fold line passes through the graceful font of the word 'Dunedin' at the top of the paper, through Aramoana township and across the narrow harbour heads, through the marae at Otakou, the church and the graveyard and the cockle beds, across the peninsula and the tidal flats at Papanui inlet, through Mount Charles and out over the cliffs of Allan's Beach, towards Antarctica.
Rodney wishes he had a gin. He mops his face with a silk handkerchief. Charles is sitting on a rock, writing in his notebook. His handsome face is stern. From up here they can see the whole panorama. The length of the peninsula lies before them, the harbour on their left and the ocean on their right.
'Purple!' chortles Rodney suddenly, as he unpacks his rucksack.
Charles looks up, frowning.
'Purple passage, let's have a purple passage,' carols Rodney. He spreads out the groundsheet. 'A purple passage before lunch.'