Spring, when the city gives in to itself and makes an enormous mess

Zurich, city of banks and fanatic cleanliness? Not only. In the seasons of spring and early summer, Zurichers are capable of throwing off those shackles.

On my arrival in April, the city repeats all my cliches: clocks, banks, glitter, neatness. Trams glide past on the minute, every few minutes. But gradually, I find that the village has snuck under the eaves of the city. Returning to my apartment one morning, I discover sheep browsing in the city centre. Primroses and violets smother lawns like weeds and Zurichers seem content to let them spread. In comparison with our mown lawns, Zurich is chaos.

Such chaos, however, is nothing compared with the human riot that is about to break out. For two days in spring, every year, bankers leave their computers, careless of soaring shares; businessmen shut up shop, professors and politicians abandon their desks. Dressing up as guildsmen of the Middle Ages, Zurichers take to the city's streets.

This is Sechselauten, when the establishment indulges in pagan ritual to banish winter and determine the length of summer. Boogg, the winter snowman, is burned at the stake on a meadow in front of the Opera House. If the Boogg takes a long time to perish, the summer will be short; if he burns quickly there will be many sunny days to come.

By two in the afternoon, the ancient guild houses which line the Limmat quay, are bustling with their former life. Tanners in leather aprons, fishermen with perch on poles, players in doublet and hose. Of course today's real craftsmen are probably the onlookers in jeans and anoraks lining the streets. Zurich's guilds have long been closed clubs for city gentlemen. It is only recently that Jews and Catholics have been allowed to join the Sechselauten parades; women still are not. "The women's role is to admire the men," a Swiss friend scoffs. She is one of Switzerland's feminists who campaigned to get women the national vote in 1971.

After three hours, now decked with flowers, the guildsmen make their way to Sechselauten meadow. We join the crowd which jostles round the Boogg, staked high above the rooftops on his giant bonfire. The sun comes out over the lake as we wait for winter to go up in flames. The fire is lit. Guildsmen on horseback set off on a wild gallop round the Boogg, trailing banners of the different guilds as the fire fans up towards the snowman. The crowd waits and watches. There is a loud explosion and the Boogg's head shatters in a dozen rockets firing into the evening sky. Bits of burning straw float down across the crowd.

"Eight minutes!" the policemen beside me says, checking his watch. "It will be a long summer." He smiles. Almost immediately, the crowd disperses. The guildsmen return to their guild houses for an evening of carousing. We retire with the ordinary folk of Zurich, for whom this communal tea- leaf gazing will be replaced by clocks and computers for another year.

CATRIONA BASS