When Walt Whitman self-published Leaves of Grass in 1855 it was a slim volume of twelve poems and he was a journalist and poet from Long Island, little-known but full of ambition and poetic fire. To give a new voice to the new nation shaken by civil war, he spent his entire life revising and adding to the work, but his initial act of bravado in answering Ralph Waldo Emerson's call for a national poet has made Whitman the quintessential American writer. This rich cross-section of his work includes poems from throughout Whitman's lifetime as published on his deathbed edition of 1891,...