He followed a more northerly route now, along one of the many radial highways 
that converged on the metropolis. After he had been riding for some time, he 
became consciously aware of a sound that had been brushing against the outer 
fringes of perceptibility for some time: a heavy, distant, and rapid drumbeat, 
perhaps twice as fast as the beat of his own heart. His first thought, of 
course, was of the Drummers, and he was tempted to explore one of the nearby 
canals to see whether their colony had spread its tendrils this far inland. But 
then he looked northward across the flat land for a couple of miles and saw a 
long procession making its way down another highway, a dark column of 
pedestrians marching on Shanghai.