American Cities run by the clock. This is truest of the largest and busiest, where the minute hand impels people through their routines without room for pause. The sleep-demolishing clatter of a five A.M. trash pickup, a breakneck dash to the subway, back-to-back conferences noted in a desk planner, business luncheons, happy hours, and more commuter sprints - these are distance markers on the constricted urban fast track, a daily marathon of appointments and schedules where it is only an apparent contradiction to say even the unpredictable occurs at predictable times.