The Hackberry Creek area did have a few proposed post offices, but none of them lasted very long, not into the 1900's. M. H. Ranney applied for one with the name Hackberry in 1881, but by the time the request was received, he would not take the office so it was moved east, and called the Hour Glass in honor of a ranch in the area, but this was discontinued in 1882. Hackney lasted about a year, 1885-1886. I'm hoping someone with more information will answer you. M. Holzwarth