If you look at 1st Tn Cavalry Carter's it has the units that where with him at Stones river it say's Marshall Battery, then go to the NPS Soldier and Sailor Database under Artillery regiments from Tn you well see Marshall Battery click on it and it shows Marshall Battery Steuben Art.. I did some looking and the other possibility is a Capt. B F White Jr. who was with a Tn artillery unit at Stones River it is listed under the Tn Artillery Units web page the name is B F Whites Jr Horse Artillery from what I could find. I Don't think they are the same unit and I couldn't find much on him. The unit is with the right people and it is noted in the write if you read it.