He is not identified, but because of his rank, there are not very many possibilities as to his ID... One very good possibility is the following: CPT William Henry Long, III BIRTH 22 Apr 1822 Powelton, Hancock County, Georgia, USA DEATH 29 Mar 1862 (aged 39) Son of Col.
Graduated from Mercer University in 1840, seven years after its founding. First Mayor of Cuthbert, Georgia. Married Sarah Mott Taylor in Monroe County, Georgia, on Aug. Organized Company F, 5th Regiment, Georgia Volunteer Infantry Army of Tennessee, Randolph County, Georgia, on May 10, 1861. Known as the Cuthbert Rifles.
William Henry Long, III, died of disease on March 29, 1862, at Tazewell, Tennessee. His body was then taken back to Georgia for burial. Ambrotype is in excellent condition behind mat and glass in full, very good+ to excellent thermoplastic case.