I need guidance on the symbolism of "structures" in The Scarlet Letter.

The Scarlet Letter contains several
categories of symbolism.  One category is the characters themselves.  Another is
nature.  "Structures" is a fairly good title for another
category.

Consider the following prominent structures in
the novel:

1. the
   scaffold


2. the prison
   door


3. the Governor's
   mansion

A few keys into the symbolic meaning of
these three prominent structures in the novel are in their location, their appearance
(especially when compared to things around them), and their
function.

All of the structures are symbolic in the sense
that they give insight into one of the themes of the book.  The scaffold and the prison
door are most closely related to Puritanical punishment.  The governor's mansion is a
symbol of the hypocrisy present in the Puritan law vs. those who carry out the
laws.