I skimmed through some of the more striking phrases. ‘My life started when he was born . . . he slipped away from life . . . Forgive me for being so angry at your disappearance . . . I think there’s been some mistake . . .’ I told her about the last line, that the mother would show the letter only to one friend.

‘My impression is of a woman who is losing her reason.’ She broke off again: ‘I have such an incredibly violent pain in the head. I have to put the letter away.’

She began to cram it back into the bottle desperately. Others – the graphologist, my friend the dog-walker, the forensic detective, myself – treated the letter more like a holy relic, an important piece of precious evidence, rolling up the sheets immaculately. The clairvoyant was in a hurry to get rid of it. Like a genie, it would not go back in without a struggle. ‘It’s hurting me . . .’ she cried, so I took the letter from her and rolled it properly and tried to reinsert it into the bottle. It took a few attempts, as I was distracted by her distress and in my haste failed to roll it tightly enough. At last I managed to slide it through the narrow neck and put the top back on.

‘Good,’ she sighed in relief. She continued. ‘Perhaps the child committed suicide? I see him in the water, I see someone trying to fish out something from the water, someone diving down to the bottom of the water. I think it is a woman. I see a boat, I see a coast, so I think it was thrown in from France, towards Brittany, somewhere like that, perhaps.

‘I wonder whether she was in hospital for a while, a psychiatric ward or something . . . I see a woman losing lots of blood, blood from her lower stomach.’ She gestured with her hands to show the flow of liquid coming from the woman. ‘I can see her being hospitalized. This woman has been in hospital. One can become mad from grief.

‘Strange, I can feel something like madness, something rather deranged,’ the clairvoyant repeated. ‘She is more than perturbed, of course one is perturbed by the death of a child, of course, but this is worse. This is a woman who has gone to the very depths, to a level of consciousness . . .

‘I don’t feel her any more, I can’t feel the woman. Strange because I see her hair, I see her wandering, I see her walking on the coast, I see her drifting all alone. I see someone – a woman who is all alone, maybe divorced or separated, but anyhow all alone. Does she mention in the letter that she is alone?’

‘She doesn’t mention a man,’ I replied.

‘In my opinion she is alone. Completely isolated. A woman all alone, very disturbed.’ A pause.