"'O mater! O fils!' she read. 'O brood continental!"

Title page of 'Leaves of Grass'
Public DomainTitle page of 'Leaves of Grass' - Credit: Thayer and Eldridge
The opening lines of a poem by Walt Whitman entitled Apostroph; it appears in the volume Leaves of Grass, which is discussed in bookmark, p. 362.

Full text

Apostrophe is a rhetorical and literary device whereby someone absent or dead is addressed as if they were alive or present; it may also be used to address an abstract or nonhuman object:

Milton! thou shouldst be living at this hour (sonnet by Wordsworth)

O Attic shape! Fair attitude! with brede/of marble men and maidens overwrought (John Keats: Ode on a Grecian Urn)