S. Perrin is probably Samuel Perrin of Hanover Co., who served in the 25th Battalion Virginia Infantry, also called the Richmond or City Battalion. His National Archives Civil War record says "Died at Field Hospital Chaffin's Farm Feby 2, 1865 of coonsumption." His widow was Mary Elizabeth Tyler Perrin, who applied for a widow's pension on 15 August 1888, stating that Samuel had died on in a hospital at Chaffin's farm on 22 February 1865 of fever,colic, and thoracic complications. He is buried in the Perrin Family Cemetery on Rte. 742 in Hanover County, where his gravestone reads Co.A - City Battalion - C.S.A. Died Feb 2, 1865. (His Civil War file places him in Co. E, not A.) Samuel Perrin was born about 1830 in Hanover County, son of Joseph Perrin and Judith Tyler Perrin.
The J. Perrin I'm not sure of, but may be Junius Pericles Perrin, son of Parke and Malinda Perrin, who was born about 1837, and lived in the Ashland District of Hanover County. According to records in the Library of Virginia Archives, he served served with the 1st Virginia Infantry Regiment, Company D, and was a sergeant when he died. He was mortally wounded at Dinwiddie Court House (Va.)on 31 March 1865. A letter is in the Library of Virginia Manuscripts Collection, dated 1 March 1862, from Junius Pericles Perrin at camp near Centreville, to his cousin John Perrin in which Junius writes about the weather, family, and Union troop movements.
Hope this is of some help to you. Mary Lou Perrin Bailey