Hello Ken & Jan,
Thanks very much for your replies.
My ancestor was apparently in the Royal Horse Guards. I know he spent some time still working for the military in the early 1900's, and possibly served in World War One (although by this time he would have been in his fifties). He was in Aldershot with his family at the time of the 1901 Census, working as a Ward Nurse at the Cambridge Military Hospital, and worked in the Army Mess just before that. Do either of you know if muster rolls are available at any online source?
Kind regards,
Steven