Privates were rifleman, you cannot use a weapon, muzzle loader, with one arm.

I have recently seen a similar set of cards but would tend to disbelieve.

If he was an officer, this was another matter, and many serviced with one arm.

About the only place one could serve with only one arm would be in a clerical position, Quartermaster's department, Nurse perhaps. I wouldn't think a Teamster or Wagoner could drive a team with only one arm.