rescue_action_in_public (ActionController::Rescue)

    # File lib/action_controller/rescue.rb, line 51
          def rescue_action_in_public(exception) #:doc:
            case exception
              when RoutingError, UnknownAction then
                render_text(IO.read(File.join(RAILS_ROOT, 'public', '404.html')), "404 Not Found")
              else render_text "<html><body><h1>Application error (Rails)</h1></body></html>"
            end
          end