My Ggrandfather was in co D 66th Ga, the book you are refering to is Four Years on The Fireing Line, by Col Cooper Nesbit, during the battle at Kennesaw Mt. my Ggrand father was in position on the left side of Burnt Hickory Rd, his brother was with the 9th Texas Calavry in position on the right side of Burnt Hickory, I've often wondered if they knew each other were there, After the battle of Franklin Tenn the confederates were in retreat into Alabama, The 9th Texas were placed with Nathan Bedford Forest Calvary to protect the retreating soldiers, this is probably where your ancestor had a run in with Forrest