Then the arrival of Doctor Indra Wallace changed everything. Despite her name, her chief racial component appeared to be Japanese, and there were times when with just a little imagination Poole could picture her as a rather mature Geisha Girl. It was hardly an appropriate image for a distinguished historian, holding a Virtual Chair at a university still boasting real ivy.

She was the first visitor with a fluent command of Poole's own English, so he was delighted to meet her.

'Mr Poole,' she began, in a very business-like voice, 'I've been appointed your official guide and – let's say – mentor. My qualifications – I've specialized in your period – my thesis was "The Collapse of the Nation-State, 2000-50". 1 believe we can help each other in many ways.'

'I'm sure we can. First I'd like you to get me out of here, so I can see a little of your world.'

'Exactly what we intend to do. But first we must give you an Ident. Until then you'll be – what was the term? -a non-person. It would be almost impossible for you to go anywhere, or get anything done. No input device would recognize your existence.'

'Just what I expected,' Poole answered, with a wry smile. 'It was starting to get that way in my own time – and many people hated the idea.'

'Some still do. They go off and live in the wilderness – there's a lot more on Earth than there was in your century! But they always take their compaks with them, so they can call for help as soon as they get into trouble. The median time is about five days.'

'Sorry to hear that. The human race has obviously deteriorated.'

He was cautiously testing her, trying to find the limits of her tolerance and to map out her personality. It was obvious that they were going to spend much time together, and that he would have to depend upon her in hundreds of ways. Yet he was still not sure if he would even like her: perhaps she regarded him merely as a fascinating museum exhibit.