They spent the next half-hour going through a list of the Communists with whom Barney had got into touch at branches of other Unions. In some cases he had been able to pick up small items of information about their private lives which would be added to their dossiers; about others C.B. was able to pass on to him further particulars that might be helpful which had been brought in by the department's network since Barney had started on his mission. Both of them knew that it was this careful collation of a mass of detail, rather than some spectacular break, that usually brought results in the long run.

When they had finished, the Colonel leant back and said: 'I take it you haven't tumbled on anything which might give us a line on poor Morden's killers?'

'Well . . .' Barney hesitated. 'Not exactly.'

'Come young feller!' For once C.B.'s voice held a suggestion of asperity. 'That's no reply. Yes or no?'

Barney pulled a face. 'Sorry, Sir. I ought to have known better than to hedge with you. But it's such an unlikely bet that I thought you might think I'd gone a bit goofy and was wasting my time.'

'Nothing's unlikely in this business. Let's have it.'

'Well, last week I thought I'd go down to Wimbledon and call on Mrs. Morden. I've never met her, but I intended to introduce myself as a member of the firm and say that I'd been sent along to enquire how she was bearing up, and if there was any way in which we could be of help to her. My idea was that now five weeks have elapsed since her husband's death she might be sufficiently recovered from the shock not to mind talking about him, and she might say something about him that hadn't seemed to her to have any bearing on the case, but would to me.'

Verney nodded. 'Good idea. What came of it?'

'She wasn't there. I got it from her neighbours on the other side of the landing that nearly three weeks ago she shut up her flat and went off to Ireland without leaving an address.'

'I see.' To himself, C.B. was thinking, 'So my warning about what she'd be up against didn't shake her, and she's probably putting her lovely head into some hornets' nest by now. Anyhow, it's some comfort that she's taken my advice about going somewhere else to live and severed the ties by which she could be connected with Morden.' Aloud, he added: 'It was from her neighbours you picked up a lead, then?'