1. John's age is stated incorrectly in the mortality index.
2. John was born about 1870, meaning that the 1798 birth date is incorrect.
3. The records refer to two men with the same name in different generations.
The JOP that married Elizabeth Harrison Gilliam was the brother of Walker Pettus, my great-great-grandfather, who was born in 1795, according to a family bible. Thus, it is unlikely that JOP was born in 1770.
The first tax record of a JOP adds the suffix, "Sr." The records for subsequent tax years omit "Sr." I have assumed that the suffix was added to distinguish the taxpayer from a younger person of the same name who died young, but perhaps my assumption is incorrect.