In late 1849 or 1850 O. C. joined the California Gold Rush, traveling to California by way of the Isthmus of Panama and setting up a claim in the Auburn area. O.C. soon left the gold fields to return to the farm in Illinois.
In the mid-1850's O. C. bought a farm just outside Tuscola, in Douglas County, Illinois. O. C. Hackett was the founding Supervisor of Tuscola township, and was elected in 1868. Hackett was elected Supervisor with a majority of only one vote over W. B. Ervin. O. C. planted Hackett's Grove, a sassafras grove situated on Section 31, Township 16, Range 9, on the east side of the township. This twenty acre grove is traversed by a branch of Scattering Fork of the Embarrass River, long known as Hackett's Run, and according to the History of Douglas County (1884), the grove had been owned by the Hackett's since long before Douglas County had an existence.
http://www.iltrails.org/Coles/early_settlers_1.htm -- Early Settlers of Coles County, Illinois
http://genealogytrails.com/ill/coles/history.html -- History of Coles County, Illinois
List of people associated with the California Gold Rush