Capt Mason, Major Hardy and the writer were senior officers on a Generals staff. I thought perhaps George Gordon, but cannot connect. No luck with Blair.
Mason and the writer were with the 7th ? at Bull Run, 1st or 2nd. None-the-less, I do not find a 7th in the Order of Battle for either battle.
The reference to a 10th pertains to a female color bearer.
Sorry, I’ve run into a dead end except for Col. George Gordon.