The new iPhone is available to buy today at GBP499 for the most basic model. The iPad appeared a few weeks ago at a couple of hundred pounds more than that. G. remarked on Saturday morning, while we were having coffee after a long night selling records at the 'Yes we Can' album launch, that what has replaced buying music is buying Apple products. Steve Jobs has convinced us all that owning an iPad (3 million of which have been sold in the last 80 days) will make us happy. When I was growing up, it was owning a record that made life exciting.

We all know that no one buys music anymore; very few people actually think the recorded product is worth anything. Most people think music should be free. Why do we keep going then? Maybe we in the music industry are as unfailingly optimistic- with no reason to be- as the migrants the musicians talk about on the compilation. But then, many migrants get to Europe, find that the streets aren't paved with gold, but make it work anyway, despite the misery and hardship.

Yesterday morning I went to visit J. on my way to pick Jo up from the ferry. J. worked for my grandparents on the farm up until my grandfather died 12 years ago, looking after the horses and I suppose the other animals too. She still lives in a little cottage in the village with a dramatic rose garden out the front. J. taught me to ride horses and I loved going out on the farm with her when I was little; she seemed to me indestructible then and not much has changed now, though she's riddled with arthritis and can hardly use her hands.

She said the BBC were coming to see her next week; they'd been reading old newspapers and found out about her winning the ploughing matches in the 60s and 70s and wanted to interview her.

The first year, she won first prize in the ploughing match. The second year, she won it again, but the boys weren't happy about a lassie winning so in the third year, when she won again, the men who won second and third swapped the trophies over.

"That's the lassie's trophy," the judge stepped forward and said when they announced the winner. "We'll sort it out at the end," they said, but they never did.

"I didn't mind for myself," said J., "but my dad was on his deathbed at the time and he was awful sad."

She didn't go in for it for the next couple of years, but when she went in for it the following year, arthritis had already got a hold of her and she had her right arm in a sling.

"I can do it with both hands though," she said, and she went on to win the match. The men who had swindled her out of the trophy two years back came in second and third position.

"I knew then I could die tomorrow," she said. "I had my three trophies and I beat those boys."

As we sat in her quiet kitchen, the Aga humming in the corner, three cars went by the window in quick succession, over the little narrow bridge just beyond the rose garden.

"That's the ten o'clock ferry in," we both said, knowing that a stream of traffic in these parts means the arrival of the boat.

The boat is the clock by which Mull time ticks. Everyone knows the timetable off by heart because without it, the papers don't arrive, the Spa shop runs out of supplies and no one gets on or off the island. There is something extremely satisfying about knowing exactly when things and people will arrive- like knowing the timetable of planes coming in and out of Dakar- but I don't quite know yet what it is.

Time has an exceptional quality here; the day lasts interminably (I have not seen darkness since I got here, even when I sleep at midnight and wake up at 7am) and there is nothing, like the call of the mosque, to mark its passing. I look out on the rocks and the glassy loch and imagine it to be 5 in the afternoon, only to find it is half past nine at night. At eight in the morning it feels like midday. But it doesn't matter what time it is, I have nowhere to be and nothing to do but write and wonder what I will do when I get really hungry.

The car is still being fixed so today I walked the four miles back from the village with a bag of kale and some potatoes so I shall be alright for a while.

When I got back, I was sunburnt so I went down to the shore in my wellies and waded into the clear water, rippled with giant plaits of rust-coloured seaweed. I swam backwards and forth, though it was quite cold. I noticed a caravan parked far-off along the way and when I splashed about loudly, two figures came around to the front of the caravan and stood watching in my direction. I could tell by the way their elbows were out that they were both looking through their binoculars.

"Oh, I say," I could imagine one of them saying, "what do you think that is? Over there, look!"

"Let's have a look," replied the other probably, focusing the lenses and nestling them into his eye sockets. "Do you think it's a seal, or maybe an otter?"

I stood up in the six inches of water I now found myself in and gave them an enormous wave. Only one of them waved back.

Last night it drizzled slightly, but the air was warm and it was still light when I went to bed at half past ten. This morning I climbed up through the bracken and ferns at the back of the house to check on the burn, the small stream from where we get our water. The peaty brown water trickled thinly across the rocks; there's hardly been any rain here all winter, H. told me, and they've been taking water from the big river to water the crops. If it doesn't rain soon, we'll be completely out of water.

This afternoon, after a few hours' writing and having taken the washing in, I walked along the shore to find a place to swim. I passed two cars parked in the lay-by along from the house, their doors open and their occupants standing with large binoculars and a telescope looking back at the house.

I stopped and said hello. The three men ignored me but after a long pause, the woman said hello back. I asked if the sea eagles were around- they nest in the tree behind our house- and they didn't reply. I asked again and one of the men said, coldly, not turning from his binoculars,

"Yes."

They started to talk amongst themselves. I stood there for half a minute then said, "Good luck" and went off.

I tramped down to the shore, across mossy humps and through the brambles and irises, and found a rocky shelf slightly protected from the wind. I was still amazed and irritated by the rudeness of the twitchers, who were camped out in my front yard, when I stripped naked and plunged into the water. I hope they could see me and would be put out too. Perhaps they would think I was a seal.

My mind is starting to unknot; now I can hear the silence as loud as anything. It is raucous and it rings in my ears where normally thoughts and over-thinking are the loudest things of all.

The man I met on the ferry from Lerwick had a job ahead of him to find the owner of the little diamond ring he'd found amongst the rubbish on the beach at Yell. I had my own ring mystery to solve, but I didn't tell him that at the time.

My older sister had a ring which my mother bought her, silver tubes filled with pink and purple perspex that glowed under neon lights and could be worn in two directions. She was my older sister and everything she had, I wanted to have too, because she was what I believed to be the benchmark of hip. When I was working at Lonely Planet, I took my first pay packet and bought a ring by the same designer from a jewelry shop in Brick Lane. I think I was 20 and it cost me £60.

Roll on a decade and that ring has been all over the world with me. Of all the lovely bits of silver I own, left to me by grandmothers and some even made by my grandmother, it's the one piece that people comment on. It's unusual maybe because what looks like precious jewels is in fact perspex, set in a heavy block of silver which never seems to dull. It is smooth and angular at the same time. It is beautiful to wear because it is soft on the skin but also extremely heavy. It suits the wide knuckles that I inherited from my Granny Wendy.

Recently I started to hanker after another piece of jewelry by this same designer. I went back to the shop in Brick Lane and showed the lady the ring. She said she didn't know who had made it and had nothing like it any more. More recently I went to another shop near my office and the woman also didn't recognise it. She got out her magnifying glass and looked at the hallmark, now almost completely worn away. "W.B" she said it said, squinting at the underbelly of my ring. "Try Google."

With a day-rate pay under my wings I spent the afternoon Googling 'W.P Perspex Jewelry' and every other permutation of those bare facts. Nothing much came up and I forgot about it for a while.

On Sunday morning I was rushing out to my studio to open up my exhibition when I stopped and carefully put on my ring. Before I got to the studio, I stopped in at a furniture-maker's studio in the next-door yard to say hello. He was listening to Ali Farka Toure on the radio and working away at a beautiful wooden chair which I stopped to touch. We chatted and as I was about to leave he pointed at my ring and said,

"You have a William Prophet."

I stopped cold because of course then I remembered his name as clear as anything. W.P., not W.B.

Ian showed me his own wedding ring, made by W.P.

"He's a friend of mine. He runs a pub now round the corner."

The pub is on my cycle route so yesterday, on my way to town, I dropped by. Everyone stared at me as I went in; only Kennington locals drink in this little hole with its navy blue patterned carpet and game machine flashing in the corner. I went to the bar and said I was looking for William.

A man came over and I told him I had one of his rings, showing him my hand.

"Oh right," he said, looking suspicious. "What's wrong with it?"

"Nothing!" I told him, and started to tell him how I had looked for the designer of this ring for some time.

He smiled and looked pleased. But said, "What do you want?" as if I had come to ask for my money back.

"I want to buy another one," I said.

"Oh," he said, then started to tell me in gushes of speech everything around the subject of how he came to be running a pub.

"I thought it'd be a hobby and then I could crack on with the jewelry," he said. "But I've had commissions for a year that I haven't been able to get down to."

He gave me his phone number and told me to come back; he'd dig out what he had upstairs.

He asked me if I came on my bike.

"I could tell by the sweat," he said.

When I was at school, the beech veneer letter rack was at the bottom of the stairs leading down from our bedrooms. I used to go to breakfast early in the morning and then come back to see if there was anything in the post for me around half past eight. When there were no letters in the 'S' rack, I felt incredibly lonely and sick in the stomach, knowing nothing much ever came in the second post and it would be another 24 hours before the post came again.

Often though there were letters from my family, especially my grandparents who used to write to me a lot. Once my grandfather wrote me a long letter and, knowing how much I pinned on getting post, divided it up into nine separate envelopes and posted them over a few days. The pages just stopped at the bottom, mid-sentence, and I had to wait another day for the next installment.

After I left school, and had left Australia, I carried on a relationship with someone who used to write me long, long letters full of news, thoughts and longing. I spent my evenings replying, crafting page after page of my own news and sadness at our separation. Everything I experienced in my days went into those letters; there was nothing that went through my mind that didn't get repeated on those thin Air-Mail pages and then folded up and sent off in an envelope to Australia. Even though we could make cheap telephone calls and we did- we spent hours on the phone too- it was those letters that meant something. They had taken time to compose; they were undistracted pieces of our lives which carried so much with them.

When I lived in Ziguinchor, my other grandparents wrote to me often and I had a lot of time to reply. Invariably I would get one envelope from them with two letters inside, one from my grandpa and one from my granny. They had both spent time with my last letter and replied in their own way, my granny's reply full of news of things she had done with the French group that she belonged to ('the French Circle") and her early mornings at Columbia Road flower market, and my grandpa's letter in large scrawling script telling me about what he had been reading, what plays they had been to see, and what he thought of the things I had told him about the people I lived with and the way we lived.

Once I told them how T. was disappointed with the little moped I had bought, wishing I had instead bought a roaring motorbike.

"Typical African," my grandpa replied, suggesting that T.'s love of expensive motorbikes was somehow connected to the greedy African dictators that he actually knew a lot about.

"Typical man," my granny replied in her version of the reply.

I have kept every letter I've ever received in the years since I left school. They are in their own shoe box, with their own ribbon tied around them, kept high up on a shelf, near the door if I ever had to grab them in a fire. My grandparents- the ones who wrote letters- are gone now but occasionally I'll forget and think to myself, I must remember to tell granny that when I write to her.

It's hard to find an hour or two of uninterrupted time to sit down and compose a letter but I did this week and though it felt unnatural and my fingers cramped up, I quite enjoyed it. I wish I had more people to write to though and then I really would find the time.