In the third stanza of "Song of Myself, " the speaker talks of his attachment to the soil and air:
My tongue, every atom of my blood, form’d from this soil, this air.
In saying this, the speaker is expressing his strong sense of kinship and oneness with the world all around him. He is not the alienated subject, because he does not see the earth and the air as objects separate from himself. The soil and the atmosphere
are not things he exercises dominion over, but a part of his being.
The speaker goes on to say that his parents, grandparents, and great grandparents were born of the same air and soil that formed him. As usual with Whitman, this sameness works on several different levels. He speaks to the idea that his family has deep roots in America, but the air and earth he is part of also encompasses the entire planet: he is the universal "I," one with all of creation.
He then becomes more specific in locating himself as a piece of this larger ecosystem, saying he is thirty-seven years old and in perfect health, hoping to live robustly until death.
Later, the speaker will mention the air again:
Breathe the air but leave plenty after me,
And am not stuck up, and am in my place.
Once again, he is emphasizing that he is part of a larger system of life, earth, and air, in which he knows where he belongs—being human can make one presumptuous or "stuck up."
Whitman's embrace of soil and air are part of his exuberant celebration of all life, all of which he feels connected to and intertwined with.