This evening I sat beside Harriet in the dining room in the sheikh’s villa. My face and arms were smothered with Aftersun, but I could still feel the heat in my skin. I drank copious amounts of cold water, which a servant poured from a copper jug into copper goblets. We ate selta, a kind of vegetable broth with lamb, fresh-baked Arab bread and hummus, and a spicy mixture of garlic and tomatoes and other vegetables I could not identify. The sheikh was in a humorous mood. ‘So, you have walked along the Wadi Aleyn, Dr Alfred. What do you think of our project now?’

I shook my head. ‘It will be very difficult. I must confess, Sheikh, I am very daunted. It is one thing to plan this project thousands of miles away and another thing to see the rocks and sand of the wadi.’

‘And another thing to feel the heat,’ added Harriet, looking rather pointedly at my sunburned nose and cheeks. Under the sheikh’s influence her mood has improved a little since we came here. She is more cheerful, although from time to time a sad, inward look still crosses her face.

‘No one who has not seen the wet season can imagine it, what it is like, how the rains fall so swiftly; just as no one who has not been here in the dry season can imagine the heat and the dust that brings. You shall see. Yemen is not just desert. There are green pastures and fields in the Hadramawt, and at Ibb and Hudaydah. Have faith, Dr Alfred, have faith!’ And the sheikh smiled and shook his head, and laughed to himself as if amused by something a child had said.

Harriet and I have been put in a guest wing at the far end of the house, away from where the sheikh and his retinue sleep. There are half a dozen bedrooms here, all large and luxurious with big comfortable beds and marble floors, with prayer mats laid out and a green arrow set in mosaic tiles, pointing the way to Mecca. The bathrooms have huge sunken baths with (I think) gold fittings. Bowls of fruit and flowers are set out and iced water can be poured from a giant Thermos. Sometimes someone lights frankincense in a burner in the central courtyard, and its strange and exotic scent pervades the whole house, making me think of church again in a distant childhood.

As I made my way along the corridor to my room just now, I passed a half-open door and heard the sound of someone weeping.

I stopped. Of course it was Harriet. Gently, I pushed at the door. She was sitting on the edge of the bed. There was just enough moonlight coming in through the filmy curtains to see the glint of tears running down her cheek. I stood there tentatively, my hand still on the door, and said, ‘Harriet? Is something the matter?’

Of course there was something the matter. What an idiotic question. She mumbled something in a choked-sounding voice. I could not make out the words. I stood there awkwardly a moment longer and then instinct took over, and I sat on the bed beside her and put my arm around her. She turned and buried her face in my neck and I could feel the moisture on her face against my skin.

‘Harriet, what is it? Please tell me.’

She sobbed for a while longer and my shirt collar became damp. It was a curious feeling, holding her in my arms like that. It didn’t feel wrong. It felt right.

She said, ‘I’m sorry. I’m being pathetic.’

‘No. Tell me what has upset you.’

‘It’s about Robert,’ she said in a trembling voice. ‘I keep thinking something dreadful has happened to him.’

Harriet had told me about her engagement to Robert Matthews, a captain in the Royal Marines. She never speaks much about him, and I never think much about him as a result, although if I do, it is with an odd, irrational twinge almost like jealousy.

‘I haven’t heard from him for weeks and weeks,’ she said. ‘I’m so worried. It’s like an ache, all the time.’

‘Perhaps he’s somewhere where he can’t answer letters,’ I suggested. ‘I imagine the communications in Iraq are difficult.’

‘It’s worse that that,’ she said into my shoulder. ‘Promise me you won’t tell anyone, if I tell you.’

I promised. Who would I tell?

She told me how the letters she had been receiving from Robert had at first been almost obliterated by the censor and then had ceased to come altogether. What was worse was that she had been contacted by something called the Family Support Centre, and all the letters she had written to him had started being returned. Then she hinted that, in some way she did not make clear, she had received information that, wherever Robert was, he was in serious danger. I tried to think of words to comfort her, and she clung to me for a moment longer, but then she became calmer and sat up straight and I removed my arm.

‘God,’ she said, ‘I must look a mess. Thank goodness it’s so dark. I’m sorry to have let you see me like this. I just lost it for a while.’

‘It must be a huge worry for you,’ I said. ‘I completely understand. I have no idea how you’ve kept so calm all this time. You mustn’t bottle it up. We must help each other. You should have said something about it before.’

‘You have your own worries, I know,’ she said. ‘I had no right to bring my troubles to you.’

‘Harriet, I know we started out on this project-that is, I know I started out on this project-on the wrong foot with you. Since then I’ve gained a great deal of respect for you, and I’m very fond of you. I want you talk to me as you would to any other friend, whenever you want to.’

She looked at me and gave a sad smile. ‘That’s very sweet of you.’ Suddenly, she leaned forward and kissed me briefly and coolly on the lips. Then she stood up and made for the bathroom, saying over her shoulder, ‘I must clean my face up. Thank you, Fred. Goodnight, and sleep well.’

I came back to my room, and now as I sit here finishing this entry in my diary, I still feel the touch of her lips on mine.

Sunday 20 November

Harriet and I went for a walk along the wadi this morning, before the sun got too hot. We left the sheikh’s house very early, and Ibrahim drove us down the bed of the Wadi Aleyn and as far along it as he could get the Land Cruiser, which was a lot further than I could have managed. Then he went and sat on the ground on the shady side of the vehicle, his back propped against it, and let us get on with it.

I had thought there would be a constraint from last night, and that Harriet would feel embarrassed by the fact I had found her in tears. But she said, as we set out along the wadi, ‘Thank you for last night. It helped to talk about it all.’

I said I was glad if I had been of help.

As we walked up the path that ran alongside the wadi, I felt a feeling of contentment I had not known for a very long time. Sheer rock walls formed the sides of a canyon, and above their tops I could discern ridges of higher mountains yet. The sky was a dark blue, and buzzards screeched and wheeled far above-their eerie cries echoed between the rock walls. There was little vegetation here: a few thorn bushes, tufts of grass, the green fading to brown as the memory of the summer rains disappeared. Here the wadi became steeper, and I could envisage it as a series of rills and small waterfalls when it was full. The salmon could get up this far. We turned a corner in the canyon and to my delight the area widened out into a gravel plateau, dissected by the dry beds of smaller streams that formed the tributaries of the main wadi.

The sight of those gravel beds filled me with excitement. I said to Harriet, ‘Spawning grounds. If the salmon ever get this far up, they will love this.’ I bent down and scooped some of the gravel up and let it trickle through my fingers. ‘The gravel is small enough here for the salmon to dig trenches with their fins and lay their eggs in them. I would never have imagined it! Perfect!’