itting in an outdoor plaza on First Street between Market and Mission waiting to meet my girlfriend after work, listening to the Master Musicians of Jajouka playing an otherworldly Moroccan voodoo riff on a Stones tape in my Walkman, thinking how strange the air felt, absolutely still, motionless, no breeze at all in the usual downtown wind tunnel by the bay when the ground began to vibrate and the shaking sped up and a loud rumble arose from millions of tons of concrete and steel and glass bouncing up and down and the pavement beneath my feet rolled in waves and I looked up at the vertical canyon of thirty and forty and sixty floor skyscrapers on all sides of me shaking from side to side, slamming back and forth five or ten feet in each direction several times a second, like dice in a cup, and glass windows began to shatter and rain down on screaming pedestrians running down the sidewalk holding jackets and briefcases over their heads and it went on and on and on and on and then stopped and every car alarm for a hundred miles kept shrieking and the dust shaken from window sills turned the air between the buildings brown all the way up to the rooftops where the skyline suddenly turned clear and blue.