I wonder if the following is your John Taylor Bruce?
John T. Bruce Born: abt. 1837 Enlisted: 17 Aug 1863, Private @ Indianapolis, IN, Michigan Residence: Indianapolis, IN, Michigan State Served: Michigan Service Record: Enlisted in Co. Batty M, Michigan First LA Batty, M Light Artillery Battery on 21 Aug 1863. Mustered out 11 March 1865 at Cumberland Gap, TN. Source: Record of Service of Michigan Volunteers 1861-65, U. S. Civl War Soldier Records and profiles 1861-1865
John Bruce Born: 1834 Died: Sept 20, 1894 Note: Army-Civil War Buried: Grand Rapids Veterans Home Cemetery, Grand Rapids, Kent, Michigan Source: www.findagrave.com which includes his obituary
Did you post this query on the applicable Georgia County board?
Do you have a copy of Martha's obituary? I was thinking it might mention more about him.
By the way, Genforum doesn't notify the poster when a reply is posted. You might want to add your email address to your profile so you'll know about a reply. Successful Searching!