The Hart's homesteaded the southwest ¼ of sec 34, directly north of Savill's and west of Heber Preece (#6 on the 1958 Highland map). John and Mary were born in England and likely arrived in the U.S. after 1870. The 1880 census showed John at 50 years old, Mary at 42, and a seventeen year old nephew, Edwin, living with them. John was listed as a "farmer and doctor". They apparently left the state or died before the next census. Nothing more is known of them. Research becomes very confusing because there are obvious mistakes in the record.
Source: HIGHLAND HISTORY: A compilation by Charles T Greenland II for the Highland Historical Society