Master of the seductive squiggle

Though hard to place in 20th-century art, Paul Klee described what he did as simply taking a line for a walk. Now a major collection of his work has gone on show in Edinburgh.

It is a magical, sometimes mystical tour through an enchanting world. Paul Klee is probably one of the least pin-downable artists of the 20th century. He cannot be tethered to any one movement, his art brilliantly singular. Not that Klee was a particularly enigmatic artist but more that his mind was always on the move. You sense that Klee was ceaselessly curious, constantly digging and delving into a wealth of ideas. This is what makes his work so intriguing.

It is a magical, sometimes mystical tour through an enchanting world. Paul Klee is probably one of the least pin-downable artists of the 20th century. He cannot be tethered to any one movement, his art brilliantly singular. Not that Klee was a particularly enigmatic artist but more that his mind was always on the move. You sense that Klee was ceaselessly curious, constantly digging and delving into a wealth of ideas. This is what makes his work so intriguing.

The Private Klee is an exhibition of more than 130 works from the Swiss Bürgi Collection. The largest private holding of Klee's work outside the Klee family collection, this is the first time it has been exhibited as a whole in Britain. And pleasingly the collection starts at the beginning of Klee's career and finishes at the end. There are bizarre pen and ink drawings of grotesque figures from his early years to late works filled with broad brushstrokes and near-hieroglyphic motifs.

What is extraordinary about Klee's sketches, watercolours and drawings is how they somewhat seductively usher you into his fantastical world. A squiggle here, an hybridised musical note there, a wash of colour, an opera singer, an acrobat, a bird. Some works teeter on the abstract, others flirt with expressionism or with symbolism. His works demand time. Time for the eye to gently excavate the swirls and whirls of line, to gaze at patches of colour, to decipher a landscape.

Born near Bern in 1879, in his late teens Klee moved to Germany. He settled in Munich and there he dipped into metaphysical texts, read treaties on music - the son of music teacher, Klee was an accomplished violinist - read up on botany and the latest findings on mental illness. And he met other artists. He taught at the Bauhaus alongside Kandinsky and met up with other members of the Blue Rider group. He travelled to Paris met Robert Delaunay and spent time in North Africa and Egypt. And his souvenirs from these encounters and travels found their way into his work. He declared that he found colour in North Africa and the landscape of Egypt - the pyramids, palm trees, furrowed fields and camels - entered his art.

Klee is the artist as hunter gatherer and these admirable magpie-like tendencies are reflected in his use of materials. Sometimes it is straightforward paper and watercolours at other times he works with small swathes of tablecloths, pieces of plywood, cotton and silk. Klee once said that he wished he could paint as though newborn. He wanted to throw off the shackles off perceived reality and describe another world. In 1920 he wrote: "Formerly we used to represent things visible on earth, things we either liked to look at or would have like to see. Today we reveal the reality that is behind visible things, thus expressing the belief that the visible world is merely an isolated case in relation to the universe and that there are many more other, latent realities..."

And this gives rhyme and reason to Klee's most famous words of wanting to take a line for a walk. Follow his line and you're not sure where you will end. Doubtless, Klee didn't know either. And there is humour. Klee was clearly no killjoy; his work is a world away from the art of harsh social commentary painted by many of his German contemporaries. But if Klee's work lacks bite, it is more than compensated for by its inventiveness. The whimsical is never overblown. The inventiveness is rarely gratuitous.

In 1933 Klee fled Nazi Germany and returned to Switzerland, though finding his home town of Bern a touch stultifying. He died seven years later in 1940, but though his last years were marked by illness caused by a skin and muscular disease, which grew progressively worse, his later work continues to deal more in delights than anguish.

The Private Klee is an extraordinary exhibition, although the politics of patronage are in the air. Hanni Bürgi, the wife of the owner of a Bern construction company, met the young Klee when she received music lessons from his father in around 1908.

She purchased her first Klee soon after. So began the Bürgi Collection and the intertwining of the Klee and Bürgi families, which continues today. Yet in the Fifties there were ructions. Felix Klee, Klee's only child, contested the ownership of Klee's estate in the courts. That is today history but the exhibition catalogue is laden with Bürgi family history and the reproduction of numerous legal documents is obviously there to avoid any misreading of past events. Klee of course wins the day.

The Private Klee: Works from the Bürgi Collection is at the Scottish National Gallery of Modern Art, Edinburgh until 22 October (0131-624 6200)