He was born in 1838/39 (7 (22 in 1861), 8 [24 probably in 1863]). He was born in Wilmington, Delaware (7, 8).
When he enlisted, he was a painter (7 [coach [illegible, perhaps beginning with a 'P'], 8 [painter]).
When he enlisted, he was 5 feet 2-3/4 inches tall, and had a light complexion, blue eyes, and light brown hair (7).
He enlisted and was mustered into service as sixth corporal on 21 October 1861 (1, 5, 7, 8). He was enlisted for three years, at Philadelphia, Pennsylvania, by Captain Bell (7, 8). He was a corporal, in company G (1, 11).
He was reduced to the ranks "of [his] own accord" on 2 July 1862 (5).
On 10 August 1863, he returned to his company (3).
On 30 December 1863, Sinex reported that he was one of 38 men who had less than fifteen months to serve who were unwilling to reenlist (2). On 2 January 1864, he was transferred to the 155th Pennsylvania Infantry, while those eligible were on veterans' leave (4).
On 3 August 1864, he was reported returned from desertion and absent wounded (9). (I suspect he was wrongly reported as having deserted, and therefore haven't added this desertion to the database.)
He mustered out at camp in the field, near Pegram House, Virginia, on 2 November 1864 when his term expired (1, 6, 7, 8, 10). He was a corporal, in companty G (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
3 consolidated morning report, 91st PA, 10 August 1863 (Private Higgins)
4 consolidated morning report, 91st PA, 2 January 1864 (Higgins)
5 company G, list of non-commissioned officers (Francis Higgins)
6 company G, register of men discharged, #40 (Francis Higgins)
7 company G, descriptive roll, entry 11 (Francis Higgins)
8 company G, second descriptive roll, entry [21] (Francis Higgins)
9 consolidated morning report, 91st Pennsylvania, 3 August 1864 (Privt Higgins)
10 consolidated morning report, 91st Pennsylvania, 4 November 1864 (Privt Higgins)
11 index to compiled service records of volunteer Union soldiers who served in organizations from the state of Pennsylvania (Francis Higgins)
Could he be the Frank Higgins, 32, born Delaware, painter, in Lincoln Nebraska in 1870 (microfilm series M593, film 830, page 123 = 43 handwritten)?