As we stare at the passing market stalls and shacks I wonder where the intensity has gone

As we stare at the passing market stalls and shacks, I wonder where the intensity has gone. The anger and wildness that the dance inspired are gone and the clouds pass, leaving a cooler Khartoum The week looms and minds return slowly to tomorrow.. ONCE THE main east-west thoroughfare of imperial Berlin, Unter den Linden survived the Weimar Republic and the Third Reich to spend nearly 30 years as the most famous dead-end street in the world when Berlin became a divided city. The dance allows the Sudanese to remain faithful to their religion without having to kowtow to the regime.At sunset, the crowd disperses through the cemetery and back to the Bedford buses. Storm clouds have gathered and look ominously like they might unleash one of Khartoum's legendary sandstorms.

Drawn from the government-controlled mosques in the city, the people can express themselves in the privacy of wasteland. Dervish "monks" not only choose a life deprived of the meanest luxury, but claim to derive strength and energy from it.The dance is, perhaps, subversive. Widespread poverty, illness and a regime that fear has kept in power has brought the Sudanese quality of life to an all-time low. If successful, the meditation expels all thoughts from the dervish's mind, allowing Allah to fill his consciousness.As I looked round me, it was obvious that the dervishes were more than just the eccentric side of Sudan's spiritual life. Turning slowly on bare heels, the dervishes test the ground, occasionally greeting friends in the crowd who come forward to kiss them. A cacophony of distorted instruments strikes up and manages to syncopate with the crowd's chant.

The whole front row begins to pump arm and torso just as Usman had demonstrated and the dervishes pick up speed, gowns blossoming into wide bells.At first one can't help wondering why they don't fall over. As a child, I could whirl for no longer than a minute before collapsing with the world heaving round my ears, but a dervish will spin for at least half an hour before being replaced by another A grin slides over his face and the eyes recede back and up. He is a showman, a ringmaster, the melodramatic director.Turning to a line of men in the front row, he whips up a long pulsing chant: "Allaaaaaah Allah. Allaaaaaah Allah." The whole crowd now joins in and the chant is soon a slow, awesome moan.Two or three dervishes have taken their positions in the arena, wearing tunics of different colours and holding rods before their faces. He charges into the crowd threatening them into a perfect circle with grimaces, pointing his whip gruffly at children and rearranging the front row so that women cannot distract the dervishes from their communion. The crowd turns to face a sombre column of dervishes swaying towards us under green banners emblazoned with Koranic script.

At their head is a terrifying man, dreadlocked and obese and bearing a whip. As hearty as a student in drag, he mimics a new bride dancing for her husband. The circle is pleased to see we understand the joke and the young man shakes his hips provocatively.The light interlude is soon interrupted by a fiercer drum that approaches from the cemetery. This is the call to prayer: no wailing broadcast from the minaret, but a tambourine man singing the Koran, circling tea-drinkers, fixing individuals in his stare, and establishing an impossibly funky rhythm for the afternoon.A small circle forms around him while a young man traces arabesques in the air with his hands and lowers mock-timid eyes to the ground. Even from afar, a sense of drama widens from this curious centre out over the flats, drawing people into this magnetic field and arranging them like iron filings around the shuffle of a tambourine. Slight humps extend as far as the eye can see, casting shadows that act as gradually lengthening gravestones.Hamed an-Niel's tomb is the centrepiece of the cemetery.