In "With the Light Guns" W.E Woodruff states, referring to Blocher and Marshall's Batteries:

"Both batteries were at the battle of Helena and Zimmerman was at Pilot Knob, in the last Price raid into Missouri; they were both at Little Rock, at the fall there of......

went south with the army from Little Rock, and participated in teh affairs growing out of Steele's effort to form a junction with Banks in teh vicinity of Camden, in 1864-5, at Prairie d' Anne and in northwesterm Louisiana; also at Jenkins' Ferry, an dpossibly at Poison Spring and Marks' Mill. Kingsland, (who suceeded Tilden) LeSueur and Cahpell, were also at teh fight at Jenkins'Ferry, where I saw the good company last; as was also Ruffner's, another of my Missouri Batteries.

I know that Blocher was assigned to support Cabell's Brigade, but I loose track of Marshall during this period.