What purpose do sentence 3-6 serve in this paragraph

Read the poem. "there is no frigate like a book" (1263) by emily dickinson there is no frigate like a book to take us lands away, nor any coursers like a page of prancing poetry-- this traverse may the poorest take without oppress of toll-- how frugal is the chariot that bears the human soul. what is the primary metaphor in this poem? question 1 options: the reading experience is compared to taking a journey. a ship is compared to a book. a horse is compared to a page. a chariot is compared to a soul.