Way out west

Art - Richard Cork finds agony and ecstasy in Turner's apocalyptic landscapes

We tend to think of J M W Turner as the quintessential Londoner, born in Covent Garden and brought up there by his barber father and a mentally disturbed mother who ended her days incarcerated in Bedlam. But the surprising truth is that Turner also had significant roots in Devon. His father was born in South Molton and two uncles lived in Barnstaple and Exeter. The West Country fully entered his blood during three fruitful trips he made there, and now the first exhibition ever devoted to the work inspired by those journeys has opened, appropriately enough, at Tate St Ives.

Turner's first tour of the West Country, in 1811, was sparked by a commission from William Bernard Cooke, an engraver and publisher who wanted him to provide images for an ambitious project called Picturesque Views on the Southern Coast of England, which was to be issued to subscribers in 16 instalments over a four-year period. The timing was perfect for such a venture: Devon and Cornwall were becoming widely admired for their luminosity, warm climate and intense colours. However, the arduous trip from London to Plymouth took almost 24 hours by bumpy stagecoach, and the poor condition of most roads in Devon made horse-drawn travel very slow. Cornwall was regarded as even more of a challenge, and few felt capable of making the effort.

Cooke didn't expect Turner to supply conventional images, dutifully depicting the topography of the area. By this stage in his precocious career, the 36-year-old artist was developing a revolutionary approach to landscape. Instead of relying on skilful fidelity, he wanted the dynamism of light and colour to transform his vision.

Turner's first visit was largely taken up with drawing on the wing, making swift summaries in pencil of the locations he passed. At the Tate's irresistible show, we can peer into the small sketchbooks he carried with him, and marvel at the speed and certitude of his response to scenes as varied as the monumental, multi-arched Barn-staple Bridge and the chaotically jostling rooftops of St Ives. Although they look skeletal, these on-the-spot studies armed him with enough pictorial information to compose watercolours and oil paintings of the same subjects after his return to London. Here, settled in the studio and relying on a formidably retentive memory, Turner succeeded in conveying the essences of the places he had scrutinised.

On his second tour, in 1813, the Plymouth artist A B Johns encouraged him to adopt a more elaborate procedure in front of his selected settings. An awed eyewitness recalled how "Mr Johns fitted up a small portable painting-box, containing some prepared paper for oil sketches as well as other necessary materials. When Turner halted at a scene and seemed inclined to sketch it, Johns produced the inviting box, and the great artist, finding everything ready to his hand, immediately began to work." It took less than half an hour to execute some of these proto-impressionist images, and their freshness is still exhilarating. An oil of Shaugh Bridge, near Plymouth, is alive with a darting, quicksilver alertness to the play of light on clouds, stone, foliage, rocks, water and even the tiny window ledge of a distant cottage in the woods.

Much of the time, though, Turner's West Country travels proved so various and unpredictable that he returned to draw-ing in his sketchbooks. On his third and final trip, in 1814, he wrote a wry letter to Johns telling him that "I got rid of my cold by catching a greater one, at Dartmouth being obliged to land from the boat half drownded with the spray as the gale compelled the boatmen to give up half way down the Dart from Totnes". Yet Turner would not have resented the sudden advent of a storm. He always relished tempestuous weather, the more apoca-lyptic the better. It stirred his appetite for heightened drama, and fed the dark strain of tragedy lurking within his capacious imagination.

This strain erupts in the most powerful of the watercolours he completed in his studio many years after the West Country expeditions. Take the ecstatic image of Plymouth painted in 1825, the foreground of which is animated by men busily mooring a boat and building a mighty timbered vessel nearby. Embroiled in their mari- time tasks, they seem oblivious of the revelation beyond. Half of Plymouth is charged with sun glare, bursting from the sky in a blaze of brightness, but dense rain clouds have massed over the rest of the city with ominous blue-black implacability. They are ready to inflict a hugely destructive onslaught, and their menace is alleviated only by a colossal rainbow curving through space in an arc of retina-dazzling brilliance. A watercolour study for this prodigious image, confined to a few sweeping washes of colour and concentrating on the fundamental opposition between light and dark, shows just how elemental Turner's art had become.

By 1834, when Turner addressed him-self to a large, deeply felt watercolour of Land's End, social observation had entirely dropped from his paintings. He was approaching 60 now, and his pre- liminary studies show a desolate locale exposed to the wrath of sea and sky. The stripped immediacy and freedom of these images is astounding: they could easily have been painted today. And they culminate in a baleful watercolour and gouache, scraped by the artist, which immerses us in storm-assailed waters off the edge of the coast. Although Long Ship's Lighthouse flares on the horizon, it has failed to save a ship foundering in the ocean. With the vessel breaking up before us, the fragments are already being swept towards the rocks. Even Land's End looks vulnerable, blurred to the point of invisibility as ferocious breakers explode against the cliffs with flurries of ghostly, terminal whiteness.

"Light Into Colour: Turner in the south-west" is at Tate St Ives, Porthmeor Beach (01736 796 226) until 7 May

This article first appeared in the 13 February 2006 issue of the New Statesman, Iran: the next war