What changes have Whitman's Leaves of Grass undergone?

Leaves of Grass is Whitman's poetry collection. 1853, Leaves of Grass 1 edition was published, including 12 poems of pre-war period such as My Song and Song of the Mainland. Later, Whitman made many revisions to this collection of poems, and by 1892, * * * published the 10 version, which became a magnificent masterpiece including 296 poems.