Thanks, rich r. The photo of the original manuscript is given in American War Songs (between pp. 114 and 115), without title, the spelling being "Father Abraham".

'Gibbon's poem was published under the title 'Three Hundred Thousand More' in the New York Evening Post, July 16, 1862, and was widely reprinted. Its patriotic appeal quickly caught the imagination of a number of composers, including Foster. Musical settings published in 1862 include those by Nathan Barker (Cincinnati: A.C. Peters & Bros.), William B. Bradbury (New York: Firth, Pond & Co.), Professor A[ugustus?] Cull (New York: Horace Waters), L.O. Emerson (Boston: Oliver Ditson), J.A. Getz (Cleveland: Brainard & Co.; the same arrangemnt appeared with attribution to "A Volunteer"), P.S. Gilmore (Boston: Russell & Patee), A.B. Irving (Chicago: H.M. Higgins), and "The Wife of a Volunteer" (Cincinnati: John Church).' (Steven Saunders and Deane L. Root, The Music of Stephen C. Foster: A Critical Edition, Vol. 2 (Smithsonian Institution Press, 1990, p. 436).

~Masato