They settled themselves at the edge of the drop down into the valley; Faraday parked his stool next to Dorian's.

While Faraday set up the easel and clipped a sheet of heavy paper onto the board, Dorian turned his paintbrush nervously in one hand. Faraday had promised to help him with his painting, but he wasn't quite sure how the artist proposed to go about it.

"Well now, Dorian Red; tell me what you think are the things a good painter should know about."

"Colour. Perspective." A pause for thought. "Composition."

The faintest suggestion of a smile shifted across Faraday's lips. "That's your considered opinion, is it?"

Dorian frowned, uncomfortable under Faraday's gaze. What did the man expect him to say?

"Well, shouldn't artists know about those things?"

"Is that what your art master told you at school? Colour, perspective, composition?"

"Well ... yes. But I've thought about it a lot, and I think he's right."

Faraday raised one eyebrow. "All right. If you've thought it through, and that's what you think an artist should have in his toolkit, let's begin with those three things."

Dorian felt confused. Faraday was going to be hard to work with if he kept this up. "So, do you think artists need to know about colour, perspective and composition?"

Faraday's eyes twinkled, as if he'd enjoyed unsettling his pupil. "Of course they should. Those things, and more besides. You and your art master are right: colour, perspective and composition are part of the essential toolkit." The twinkle intensified. "So's having your own opinion. There are no prizes here for regurgitating what art masters say in class. I want to hear what you think."

"Well, I told you. I've thought about it, and I think those things are important." Dorian couldn't quite keep the annoyance out of his voice.

Faraday looked amused. "Good, then. Colour, perspective, composition; having your own opinion, and being prepared to defend it. All essential." He handed Dorian a clean palette. "So show me colour, perspective and composition at work."

Faraday gestured at the lake glimmering darkly below. "There's Ullswater. I want you to make a colour sketch. Show me what you see. Then, we'll look at refining your technique." Faraday stood up. "I'll be inside. Come and find me if you want me for anything. I'll come back in an hour or so to see how you're getting on."

Working alone in the open air, Dorian relaxed into his task. The view was beautiful: sunlight and shadow shifting across the hills softened their harsh shapes, and the lake's rippling surface ruffled beneath a light wind. Slowly, his painting took shape. He hadn't noticed how much time had passed until he heard Faraday walking across the clearing, boots swishing in the thick grass.

Faraday pulled the second stool over close to Dorian, and sat down. He ran an assessing eye across the painting.

Bold use of colour. Everything was expressed in hues a shade darker, a tone more intense, than the reality before them. Under Dorian's brush, the vista had taken on a moody, brooding character. Faraday's eye skimmed across the violet-grey crags limned with gold rearing up over shimmering lead-blue water - a monumental landscape, overpowering in its scale.

And yet - something in the way the light moved down the cliff-face and across the water drew his eye down to the lower right-hand corner of the picture, where a tiny solitary figure stood in a pool of yellow sunlight at the edge of the mere.

Dorian stopped painting, and looked at Faraday, who nodded.

"Good work," he said. He pointed at the figure on the shore. "How long was he standing there?"

"Only a moment."

"But you put him into your landscape anyway."

"It felt right."

The artist was watching him intently. "But...?"

"Well... Mr Carstairs, the Art master, says art's about reproducing our perception, not our imagination."

"And do you think that?"

"I know what he means: he means we should try to show what we see."

"On one level, he's right. If you can't produce the image you want to show, it's not much use. But a painting's not a photograph. If you want an accurate record of what something looks like, then take a bloody photo of it. What the artist can do that the camera can't is to show you how to look at it." He pointed at the figure in the corner again. "Why is he important to the picture?"

"Because he was so small, and he was only there for a moment. The view over the lake is huge shapes; everything fits together on a massive scale. He was there and gone in such a short time." Dorian looked uncertain. "Do you think putting him in is a distraction?"

Faraday gave a lopsided smile. "Do you?"

"No. It was something that happened in a few seconds, in a landscape that's been shaped over millions of years. Like two different time scales intersecting. If I'd been looking in the other direction, I wouldn't have seen him at all. Maybe it's not important, but I wanted to capture it."

Faraday pointed to the faint shaft of sunlight slanting across Dorian's picture. "This is good. You've shown us that there's something else to look at here, not just the hills and the lake and the sky. Your instinct is sound. You can develop your technique a bit - make this more subtle - but this beam of light draws the whole thing together, and shows us what to look at. How to look at it."

Faraday picked up his sketch block and a clean brush.

"Here, watch this," he said. "Try showing the light this way."

With a few sure, swift strokes, Faraday sketched out the crags, solid and dark. Then, dipping a smaller brush in yellow-white paint, he scattered minute splashes of sunlight down the cliff face, skipping off the ridges and crests.

Dorian looked at his own effort, a misty shaft of translucence slanting across the hills and lake, then looked back at Faraday's sketch.

"I like yours better," he said. "It looks more natural."

"But still has the same effect? Drawing the eye down?"

"Yes." Dorian looked up at Faraday. "More subtle."

Faraday gave a wry smile. "Subtlety has its place." He pointed to Dorian's treatment of the lone figure on the shore. "In fact, you were using a fairly similar technique here, where you showed the sunlight on the edge of the water. And up here, where you've put this edge of gold on the crag." He held his sketch block up next to Dorian's painting. "Put this technique to work in your picture, and it wouldn't look out of place when you consider the sunlight on the cliff-top and the shore."

Straightening up, Faraday clapped Dorian on the shoulder. "Good work for today, Dorian Red. Let's finish up; the light's going over behind the fells. Put your stuff in the studio, then come and give me a hand in the kitchen. Can you peel potatoes?"