What metaphors are used in The House of the Seven Gables by Nathaniel Hawthorne?

As the train rushes them from their home to some unknown destination, the usual metaphor of travel, that of taking someone into the future, is turned on its head. Clifford and Hepzibah have so long lived in the past that the train ride they take actually delivers them to the present. So taken by the speed and newness of her situation, Hepzibah asks: "Clifford! Clifford! Is not this a dream?" To which her brother replies: "A dream, Hepzibah . . . on the contrary, I have never been awake before!"