Dunadd Rock had been the capital of Dalriada, one of the early and formative kingdoms in Scotland. The footprint — looks more like a bootprint, actually, just a smooth hollow in the stone — was where the new king had to place his foot when he made his vows, symbolically — I suppose — to join him to the land.

"Can I have a look?" Verity said. Lewis handed her the glasses, arid she leant against the stone battlements, supporting her belly. Lewis stood behind her, chin lowered onto her shoulder.

"Right at the summit, isn't it?" Verity asked.

"Yep," Lewis said.

She looked at Dunadd for a bit. "I wonder," she said, "if you had one of your feet planted there, when you gave birth…»

I laughed. Lewis went wide-eyed, drawing up and back from his wife. She turned round, grinning wickedly at Lewis and then me. She patted Lewis's elbow. "Joke," she said. "I want to be in a nice warm birthing pool in a nice big hospital." She turned back to the view. Lewis looked at me.

"Had me fooled," I shrugged. "Runs in the family, after all."

"Can you see that stone circle, too?" Verity said, lifting the binoculars to gaze further north.

Earlier that day, Helen Urvill, Verity and Lewis and I had been behaving like tourists. The land around Gallanach is thick with ancient monuments; burial sites, standing stones, henges and strangely carved rocks; you can hardly put a foot down without stepping on something that had religious significance to somebody sometime. Verity had heard of all this ancient stoneware but she'd never really seen it properly; her visits to Gallanach in the past had been busy with other things, and about the only place she had been to before was Dunadd, because it was an easy walk from the castle. And of course, because we had lived here most of our lives, none of the rest of us had bothered to visit half the places either.

So we borrowed Fergus's Range Rover and went site-seeing; tramping through muddy fields to the hummocks that were funeral barrows, looking up at moss-covered standing stones, plodding round stone circles and chambered cairns, and leaning on fences staring at the great flat faces of cup-and-ring marked rocks, their grainy surfaces covered in the concentric circular symbols that looked like ripples from something fallen in a pond, frozen in stone.

Did I ever tell you about the time I used to be able to make televisions go wonky, from far away?"

It was a bright and warm day, back in that same summer Rory had come out to the Hebrides with us. Rory and I were walking near Gallanach, going from the marked rocks in one field to the stone circle in another. I remember I had a pain in my side that day and I was worrying that it was appendicitis (one of the boys in my class that year had almost died when his appendix had ruptured). It was just a stitch, though. Uncle Rory was a fast walker and I'd been intent on keeping up with him; my appendix waited another year before it needed taking out.

We had been visiting some of the ancient monuments in the area, and had started talking about what the people who'd built the cairns and stone circles had believed in, and that had led us on to astrology. Then suddenly he mentioned this thing about televisions.

"Making them go wonky?" I said. "No."

"Well," Rory said, then turned and looked behind us. We stood up on the verge as a couple of cars passed us. It was hot; I took off my jacket. "Well," Rory repeated, "I was… a few years older than you are now, I guess. I was over at a friend's house, and there was a bunch of us watching Top of the Pops or something, and I was humming along with a record. I hit a certain deep note, and the TV screen went wavy. Nobody else said anything, and I wondered if it was just coincidence, so I tried to do it again, and after a bit of adjusting I hit the right note and sure enough, the screen went wavy again. Still nobody said anything." Rory laughed at the memory. He was wearing jeans and T-shirt and carried a light jacket over his shoulder.

"Well, I didn't want to make a fool of myself, so I didn't say anything. I thought maybe it just worked on that one particular television set, so I tried it at home; and it still happened. The effect seemed to work from quite a distance, too. When I stood out in the hall and looked into the lounge, it was still there, stronger than ever.

"Then we were going up to Glasgow, mum and I, and we were passing a shop window full of TVs, and so I tried this new gift for messing up TV screens on them, and hummed away to myself, and all the screens went wild! And I was thinking Great, I really can do magic! The effect is getting stronger! I could appear on TV and do this! Maybe it would make everybody's screens go weird!"

"Wow," I said, wanting to get home and try this myself.

"So," Rory said. "I stopped in my tracks and I asked mum. I said, 'Mum; watch this. Watch those screens. And I hummed for all I was worth, and the pictures on the screens went wavy. And mum just looked at me and said, 'What? And I did it again, but no matter how hard I tried I couldn't get her to see the effect. Eventually she got fed up with me and told me to stop being silly. I had screens going mental in every TV shop we passed in Glasgow that day, but nobody else seemed to be able to see it."

Rory grimaced, looking across the edge of the plain beyond Gallanach to the little rocky hill that stuck up from the flat fields.

"Now, I wish I could remember just what it was that made the penny drop, but I can't. I mean, usually a beautiful assistant says something stupid and the clever scientist says, 'Say that again! and then comes up with the brilliant plan that's going to save the world as we know it… but as far as I remember it just came to me."

"What?" I said.

Rory grinned down at me. "Vibrations," he said.

"Vibrations?"

"Yeah. The vibrations I was setting up in my own skull — actually in the eyeball, I suppose — were making my eyes vibrate at about the same frequency as the TV screen flickers. So the screen looked funny, but only to me, that was the point. And it made sense that the further away you were from the screen — as long as you could still make it out, of course — the more pronounced the effect would appear." He looked down at me. "You see?"

"Yeah," I said, "I think so." I studied the road for a bit, then looked up, disappointed. "So it doesn't really work after all?"

Rory shook his head. "Not the way I thought it did, no," he said.

I frowned, trying to remember how we'd got onto this. "What's that got to do with what we were talking about?" I asked.

Rory looked at me. "Ah-ha," he said, and winked. He nodded at a gate set in the low wall facing the road; beyond were the standing stones. "Here we are."

"Here we are." The stair-door creaked open; I went to help Helen. She handed me a tray with four pewter mugs. The mulled wine steamed; it smelled wonderful. "Mmm, great," I said. Helen took my hand and stepped out through the little half-size door onto the battlements. Her broad face was tanned and her body looked lean and fit after some early-season skiing in Switzerland. She wore Meindl boots, an old pair of leather trousers that had belonged to her mother, a cashmere sweater and a flying jacket that looked distressed enough to have seen action over Korea, if not Greater Germany. Her hair was shining black and shoulder length.

She took a mug. "Help yourself," she said. "Any sign of him?"

"Nope," I said. I held the tray out to Lewis and Verity, who made the appropriate noises and took a mug each.

Helen nodded at the corner of the airmail package inside my jacket. "Still incubating that, Prentice?"

I grinned. "Yeah."

We stood there sipping the hot, spicy wine, looking north.