This manuscript of the 1860
Calamus 1 offers the interesting
variant reading:

And now I care not to 
   walk the earth unless 
   a comerade walk by my 
   side,
And now I cannot sing 
   other songs -- only those
   of comerades,
For now I know the unexhibited life
   which contains all 
   the rest,
And now I proceed to
   enter that substantial
   final life,
I proceed O America
   to leave you my bequest
   till I do more for you
   than any other man has done
   for you,
I proceed to bequeath to you types
   of atheletic love for the
   future for the young men,
I proceed to celebrate the need
   of comerades.--