Greg:
The Vigilant Rifles Co. SC Militia was organized in December 1860, with volunteers from the Vigilant Fire Engine Co. of the Charleston Fire Department. It was accepted for state service on 29 December 1860, and sent to Sullivan’s Island to reinforce the Citadel Cadets. It was relieved from duty on 18 January 1861, whereupon it was converted to artillery and attached to the 1st SC Militia Artillery. On 23 February 1861, it was ordered to take charge of the Five Gun Battery on Sullivan’s Island, and remained there until relieved on 22 April 1861. It was recalled to active duty on 17 September 1861, and was stationed at Fort Pickens on Battery Island until 1 November 1861. Its officers were Samuel Yeadon Tupper (Captain), John M. Harleston (First Lieutenant), and John C. Martin (Second Lieutenant).
Hope this helps.
Fred Knudsen