When I heard the Learn’d Astronomer (Unabridged)

Whitman claimed that after years of competing for "the usual rewards", he determined to become a poet. He first experimented with a variety of popular literary genres which appealed to the cultural tastes of the period. As early as 1850, he began writing what would become Leaves of Grass, a collection of poetry which he would continue editing and revising until his death. Whitman intended to write a distinctly American epic and used free verse with a cadence based on the Bible.
At the end of June 1855, Whitman surprised his brothers with the alreadyprinted first edition of Leaves of Grass. Whitman paid for the publication of the first edition of Leaves of Grass himself.