Bates (1) has
He was 26 years old when he was enlisted (7). He was born in Philadelphia, Pennsylvania (7).
He was 5 feet 7-1/2 inches tall, and had a dark complexion, grey eyes, and black hair (7).
He was enlisted and mustered into service on 11 September 1862 (1, 7, 8). He was enlisted for three years, at Philadelphia, Pennsylvania, by Lieutenant Gregory (7, 8). He served as a private in company C (1).
On 30 December 1863, Sinex reported that he was one of 30 men who had more than fifteen months to serve who were willing to reenlist (4). On 2 January 1864, he was transferred to the 155th Pennsylvania Infantry, while those eligible were on veterans' leave (5).
He may have returned to duty from Brigade Headquarters on 2 May 1864 (9).
On 17 November 1864, Sellers included him in a report "[i]n compliance with S.O. 59 dated Hd Qrs 5 Army Corps November 15" 1864" (3).
He was killed in action on 18 June 1864 near Petersburg, Virginia (1, 6, 7, 8, 10). His body was buried on the field (6).
The final papers were sent to the Adjutant General on 8 August 1864 (7).
On 18 May 1868, his widow, Matilda Hoover, applied successfully for a pension (4, 11).
1 Bates, Samuel Penniman. History of Pennsylvania volunteers, 1861-5. Harrisburg: B. Singerly, state printer, 1869-71. 5 volumes. 'Ninety-first regiment', volume 3, pages 186-233. (In the roster)
2 letter, Sinex to Marvin, 30 December 1863 (Wm T Hoover)
3 letter, Sellers to Bartlett, 17 November 1864 (William T Hoovan)
4 pension index, by name (William Hoover)
5 consolidated morning report, 91st PA, 2 January 1864 (Hooven)
6 company C, register of deaths (Wm T Hooven)
7 company C, descriptive roll, entry 104 (William T Hooven)
8 company C, untitled list, probably of status at muster out, entry 93 (Wm T Hooven)
9 consolidated morning report, 91st Pennsylvania, 2 May 1864 (Hoover [uncertain ID])
10 consolidated morning report, 91st Pennsylvania, 29 June 1864 (Pri Hooven)
11 pension index by regiment, 91st PA Infantry, company C (William Hoover)
[I did not find an entry for him in the index on <www.ancestry.com> to the 1890 veteran's census (searched May 2007)]