John S. Black, Capt. William A. Donald’s Company, Rockbridge County Virginia Reserves, age 48, joined for duty and enrolled April 16, 1864 at Lexington, Va. for the war, presence at the Muster-in Roll of June 6, 1864, not stated, no other records

The Rockbridge County Virginia Reserves was organized April 16, 1864, with four companies. It was consolidated into three companies August 8, 1864, by order of Col. E. G. Lee, commanding Reserve Forces of Valley District, as assigned to the 10th Battalion Virginia Reserves, as Companies A and B, and to the 7th Battalion Virginia Reserves as Company C

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J. S. Black, 3rd Corporal, Company B, 10th Battalion Virginia Reserves (4th Battalion Valley Reserves), enlisted April 16, 1864 at Lexington, Va. by J. B. Bond for the war, recorded on the October 31, 1864 muster roll, dated December 27, 1864, as Absent without leave from August 17, 1864, no other records, never paid, no further records

This thread contains some information on this unit:
http://history-sites.com/cgi-bin/bbs62x/vacwmb/webbbs_config.pl?md=read;id=9534

Compiled Service Records of Confederate Soldiers Who Served in Organizations from the State of Virginia

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Black, John Samuel, Pvt., Rockbridge Senior Reserves, 10th Va. Bn., b. Va. circa 1817. Farmer, age 43, 6th Dist. 1860 census. Enl. Steele’s Tavern 4/16/64. Age 48, 5’ 9”, light complexion, grey eyes, light hair. Placed on list [sic] duty because of chronic bronchitis 8/18/64 and assigned to Quartermaster Dept. NFR. d. near Davis Station 4/27/94, Bur. Mt. Carmel Presb. Ch. Cem.

The Confederate Soldiers of Rockbridge County, Virginia: A Roster, p. 29

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