He attended the University of Georgia (UGA) in Athens, where he was a member of the Phi Kappa Literary Society and earned a Bachelor of Arts in 1861 in engineering.

Hemphill, who became Anderson's son-in-law in the subsequent six months (having married Emma B. Luckie in 1871[2][7]) was placed in full charge of the Atlanta publication.

[6] In 1883, Hemphill was one of a group of investors who incorporated the Fulton County Street Railroad (horse cars), which was later electrified, and became famous for its Nine-Mile Circle route to what is now Virginia-Highland.

[3] Hemphill was first elected to the position of (Atlanta) city councilman-at-large in 1887, the same year he began an unsuccessful banking career.

[10] During his tenure the first building of what became Grady Memorial Hospital was built and a fresh-water pumping station was established on the Chattahoochee River replacing the need for various wells and cisterns (for fires).

[11] Part of the 55 acres (220,000 m2) purchased for the associated reservoir included a newly built street named in his honor – Hemphill Ave. After leaving office, Hemphill read about the Cotton Palace in Waco, Texas, and suggested that Atlanta could stimulate growth by hosting what would become the Cotton States and International Exposition of 1895.