The naturalistic imagery, building towards crescendo, becomes perhaps a little
too repetitive here, but remains symbolic. It translates to a negative vision
of Man as locked in a prison ("closed" by a "bar") made up
of dreams, illusions and subjectivity (silver, clouds and the "stillness"
of the Placid Gulf itself), while interacting with a hostile larger world (the
"surf-fretted seaboard"). Significantly, the image occurs as Linda experiences
the "torture" of certitude that Nostromo and Giselle will meet. It is
as if to say, in this negative worldview, lorded over by this oppressive machine
of society, why wouldn't the People flee to the dream of utopia? It is
these thoughts (occurring to Linda on the allegorical level only) that cause the
voice of law to sweat, as if with doubt in her convictions.