Green Lights

It happens more often than I intend, that I’m walking out of Oxford down the Abingdon Road near midnight. A friend once called the walk “the most boring in the city”, and I can see what she meant – it’s just a road – but I’d catch the bus if I didn’t enjoy it.

Part of the enjoyment is physical. This is a journey that not only needs no navigation, I don’t even have really to look where I’m going, I know the way so well. So my body very quickly settles into the rhythm of steps. It feels like a smooth-running, well-ordered system, even if (as I frequently am), I’m coming home from the pub. This is one extreme of walking, the opposite of the Pennine Way, Torres de Paine kind, and in its own way it’s very satisfying.

Meanwhile, my mind is free to do as it pleases, and in this context it slips its moorings in the everyday more easily, and enters a peculiar zone of frantic but untroubled activity. My eyes register regular sights – the view from Folly Bridge down the Thames, the window of the uninsulated house where the pigeons ruffle themselves against the window, the great amorphous forms of the lime trees over the fence in one of the playing fields. I tend to put my headphones in and listen to what I can find on the radio, as there’s little else to hear but buses, police cars and taxis passing to my right. It’s best when there’s some complicated dance music. This seems to plug into the visual part of my brain and enormously enhance its intensity. It also fits with the rhythm of the walk.

Suddenly I find myself alive to hundreds of effects of light, and in particular its filtration by the flesh of leaves. If this sounds intoxicated, it should. The effect is more than one of sight; it carries a large emotional charge – a feeling that anything can be achieved or restored.

I don’t plan to try to convey that part of the experience. But I do want to describe the leaves. In winter, the light seems to nest in the bare twigs overhanging the road. Each street lamp has laid its egg in the branches. In spring, the twigs begin to bud and the colour play begins.

Imagine the effect of each lamp in the bare tree as a globe of orange or white light. In the centre is the bulb itself – its brightness eliminates the line of any twig that crosses it. Around each bulb is its aureole, where the light is less intense and twigs emerge.

Each twig has a skin of bark, reflective where the light falls, otherwise black shadow. So the light of the bulb lies at the heart of an intricate net whose threads thicken the further away they are from the light itself.

When the buds come, they spot the black-white structure of the net with points not quite dark. The light goes through them enough to throw a touch of green – just the faintest touch – into the picture, as you might find animal tracks pressed just into the topmost crust of a dried-out path.

As the weeks pass the leaves flush and their edges creep across the face of the light. At first they’re close to transparent, webs of structure. The chlorophyll increases, and the tissues thicken, and the wavelength of the light that passes through them grows. The colour is never pure green, but green-and-orange, green-and-blue depending on the bulb in the streetlamp. Sometimes one of the traffic lights down the road is on red, and this dominates all the other shades.

Each leaf’s colour is affected by that of the leaves around it, with the beams passing through filter on filter and shifting again and again – aspects of light manipulated by the breeze.

The structure and shape of the leaves also has an effect. Hawthorns are strange hands, the veins showing like bones. Sweet chestnuts are gold, but horse chestnut jagged and darker. In the intricacy of the shape and visible struts of a lime leaf, I am reminded of computer images of the Mandelbrot set. As summer comes on, apple and cherry trees become patterned by the first swellings of fruit.

As I write this in mid June, the leaves are fully formed but still fresh, skeins through which light passes easily to interact with the music I hear, the beat of my steps, the smell of the cool air. Time does not disappear, but alters, is measured by seasons as much as hours. I duck under low-hanging branches and instantly look up for the sky, the trees, the patterns. The road stretches ahead of me, not into darkness, but into more light.