Breaking suddenly upon the steady drumming of the trucks, the prolonged and husky roar of a locomotive whistle saluted an immediate grade-crossing. Roused by this sound from his solitary musings in the parlour-car of which he happened temporarily to be the sole occupant, Mr. David Amber put aside the magazine over which he had been dreaming, and looked out of the window, catching a glimpse of woodland road shining white between sombre walls of stunted...