Organization of the Army of the Potomac, Maj. Gen. George
B. McClellan, U. S. Army, Commanding, September
FIFTH ARMY CORPS.
Maj. Gen. FITZ JOHN PORTER.
[I didn't transcribe the first and second division]
[footnote:] This division was organized September 12,
and reached the battle-field September 18. [end of footnote]
Brig. Gen. ANDREW A. HUMPHREYS.
Brig. Gen. ERASTUS B. TYLER.
Col. Edgar M. Gregory.
126th Pennsylvania, Col. James G. Elder.
129th Pennsylvania, Col. Jacob G. Frick.
134th Pennsylvania, Col. Matthew S. Quay.
Col. PETER H. ALLABACH.
123d Pennsylvania, Col. John B. Clark
131st Pennsylvania, Lieut.Col. William B. Shaut.
133d Pennsylvania, Col. Franklin B. Speakman.
155th Pennsylvania, Col. Edward J. Allen.
[I didn't transcribe the artillery or artillery
[source: Official Records series 1 volume 19 part 1 at page 175]