Re: Nichols' Arkansas Cavalry Regiment
Sid Jackman was associated with early war units that became the 7th/16th MO Inf. His 1864-65 regiment was known as Jackman's MO Cav.
BTW I could not find a T. W. Jackman commanding Slemons' 2nd AR Cav. I think the order of battle listing him as lt Col of the unit is a misprint.