'I'll send a car for you at twelve,' says Nelson.

Much to Ruth's secret disappointment, Nelson does not send a police car complete with flashing blue light.

Instead he appears himself, driving a muddy Mercedes.

She is waiting, as agreed, by the main gate, and he does not even get out of the car but merely leans over and opens the passenger door. Ruth climbs in, feeling fat, as she always does in cars. She has a morbid dread of the seatbelt not fitting around her or of some invisible weight sensor setting off a shrill alarm. 'Twelve and a half stone! Twelve and a half stone in car! Emergency!

Press ejector button.'

Nelson glances at Ruth's rucksack. 'Got everything you need?'

'Yes.' She has brought her instant excavation kit: pointing trowel, small hand shovel, plastic freezer bags for samples, tapes, notebook, pencils, paint brushes, compass, digital camera. She has also changed into trainers and is wearing a reflective jacket. She is annoyed to find herself thinking that she must look a complete mess.

'So you live out Saltmarsh way?' Nelson says, pulling out across the traffic with a squeal of tyres. He drives like a maniac.

'Yes,' says Ruth, feeling defensive though she doesn't know why. 'New Road.'

'New Road!' Nelson lets out a bark of laughter. 'I thought only twitchers lived out there.'

'Well, the warden of the bird sanctuary is one of my neighbours,' says Ruth, struggling to remain polite while keeping one foot clamped on an imaginary brake.

'I wouldn't fancy it,' says Nelson. 'Too isolated.'

'I like it,' says Ruth. 'I did a dig there and never left.'

'A dig? Archaeology?'

'Yes.' Ruth is remembering that summer, ten years ago.

Sitting around the campfire in the evenings, eating burnt sausages and singing corny songs. The sound of birdsong in the mornings and the marsh blooming purple with sea lavender.