For some moments profound silence and darkness had accompanied a Sierran stage-coach towards the summit. The huge, dim bulk of the vehicle, swaying noiselessly on its straps, glided onward and upward as if obeying some mysterious impulse from behind, so faint and indefinite appeared its relation to the viewless and silent horses ahead. The shadowy trunks of tall trees that seemed to approach the coach windows, look in, and then move hurriedly away, were the only distinguishable objects