Savernake Road resident Ann Wroe s Being Shelley is published this month. Here she tells how she wrestled with the biography during long walks on the Heath I never thought I would write a life of Shelley. I tried really hard not to. I d had an idea it

Savernake Road resident Ann Wroe's Being Shelley is published this month. Here she tells how she wrestled with the biography during long walks on the Heath

'I never thought I would write a life of Shelley. I tried really hard not to. I'd had an idea it might be a challenge to write the life of a poet, because poets are not really living here at all, but are out in their visions and their dreams. But I thought I would pick someone quieter, less known. One of those Irish monks, perhaps, living on prayer and watercress in a cave with a cat.

Then one day in 2002 I was suddenly knocked for six by his poems, as though I had never read them before. One reading of Ode to the West Wind was all it took. I bought a battered paperback from a secondhand bookshop and, lying in the grass on the cliff tops of Sussex and the Isle of Wight, I read his poems over again.

Three things particularly enthralled me. First, that Shelley sees things, and goes to places, almost no other poet touches. Second that he goes there as a seeker and a challenger, with no idea what will happen to him. He's a spiritual adventurer to the very edge and, if he can, beyond the edge. And third, Shelley perfects the poetic art of dissolving into a scene and becoming one with it, so that all those magical transformations would be part of his life, too.

I found myself hooked on trying to write this life. Yet the world has too many books on Shelley, thousands of them. A huge Shelley industry keeps watch over him. Every book I borrowed from the London Library was marked in the margins with corrections, expostulations, quotations, tea stains and tears. I sometimes felt I was working in the midst of a swarm of buzzing, stinging, bees. I didn't want to be there, not for a minute.

I've never taken so many brooding walks on Hampstead Heath as with this book. I argued with myself constantly, filling notebooks with reasons why I shouldn't write about him. I was scribbling them down furiously into a lot of small ring-bound notebooks, which seemed for some reason - perhaps because they were much the same size as Shelley's notebooks - just right for the job. On the other hand I was trying desperately not to get drawn in.

In July 2004, while working in California, I gave myself a month to embrace or drop the subject. I became too busy to think about it; but one broiling afternoon, on the beach at Santa Monica, I looked up to see a single white sail out on the blue sea. That Shelleyan motif - the lone sailor setting out for unknown shores - tore my heart and proved to me how deep my thinking had gone.

Six months later, on a freezing day in January, I walked across the Heath to argue with myself yet again; the Vale of Health pond was hung with fog and rainbows, those sunbows that Shelley saw on every side, and a single white seagull flew above the water. Clearly, resistance was hopeless.

For all my struggling, I couldn't drop the subject. "Self, that burr that will stick to one," wrote Shelley. He was the burr that had stuck to me.

There remained the problem of writing this life in a way that would work. Not a biography, in the strict sense - Shelley's day to day life interested me to a point, but seemed of little interest to him. He thought earthly life was all illusion and I took those opinions seriously. When I read other people's biographies, the man would be richly illuminated, but the poet--the spirit who had so transported me--would slide away.

The other way to deal with a poet is to leave the life and the letters and write literary criticism; build a barrier between the poet and the man.

But I've always hated lit crit and the way it can kill poetry by pinning it down when it is meant to fly. The man will always remember that he has been a poet, however fleetingly and the poet will know, to his frustration (and perhaps no poet was more frustrated than Shelley) that he is still mortal, still a man, still bound to time. Somehow, these two had to be woven together.

The answer lay in Shelley's notebooks; the rough drafts from which the poems came. Most of these are kept in the Bodleian Library in Oxford, locked away and handled only by the most elite of scholars. Since I wasn't one, I had to use facsimiles.

The Shelley I wanted to write about was there, alive, in the smallest things: the dipping and pressure of the pen, the formation of a riser or descender, the fall of a line, the search for the word... deleting and deleting until it's right; sometimes never finding it, leaving a space in the hope that it will come.

Shelley thought it extremely important to leave "vacancy" as he called it, to keep spaces open for inspiration to work in a line, just as he could feel the spirit moving in the pores of his own body. All through these notebooks, you find little pauses and doodles of leaves and clouds that show him waiting, suspending thought, for the moment when the divine breath will blow over him (his image, again), like the wind in the strings of a lyre.

There, in the private drama of the notebooks, man and poet struggled together.

Another problem was I was dealing with the life of a poet, which Shelley insisted, was not lived in physical time but was an unfolding of eternal powers. A poet lives and works on earth, gets better at his craft; but does not necessarily know more, or see more, than he did as a child. His journey towards enlightenment does not progress that way. I decided to approach Shelley's search for himself, not through time at all, but through earth, water, air and fire.

By then I was in so deep that I thought I might as well go in deeper. There is no sense in approaching a being like Shelley unless you give him all you have.

I no longer feel that I really have bolted away from this. There was no way Shelley was going to stop elbowing me in the ribs. And whenever I get those sudden, sharp intimations of him in the west wind, or the skylark's song, or the light on the sea, or the evening star, I feel glad to have tried.

Being Shelley by Ann Wroe is published by Jonathan Cape at £25.