Have a plan — don't stick to it

The garden wall is made of sandstone, off-cuts from a quarry at the foot of the dividing range. “We've hauled tons of rock from there,” says Rhyl. She's a sculptor, and this wall, which encloses a terrace of flagstones at the front of the house, is just one of the things she's made from all that scree. Three hundred gargoyles in the university quadrangle are some others.

This is the kind of wall you shape as square as a hedge — a yard high, a yard thick — out of chunks of rocks as irregular and fractal, as leftovers from a mullock heap. It's a chaotic mosaic, finished plumb, through three dimensions. Four, if I include the morning and all the time it took to make the rocks, which compose the wall. And I'm sitting on it in the shade of jacarandas on a hot morning, and I'm talking to Rob over the sound of water falling from an iron pipe into a fishpond.

Rob's a potter and a builder, and he's Rhyl's partner. He used to dream impossible forms and wake to make them. He's imagined just about everything — the extensions to the house, the shaded verandas, the gates — that I can see from where I sit.