George Ramsburg and his Oil Pull tractor.
George is probably running a threshing machine at a local farm. The Remsburgs threshed all over Eastern Frederick County from Thurmont to Mt. Pleasant. Notice the railroad jack and leveling blocks under the rear wheels, the belt needed to have a straight run between the tractor flywheel pulley and the thresher. Since the Oil Pull tractor ran on kerosene and did not pose the threat of sparks like the steam engines, they could use shorter belts and work closer to the barn when running the thresher.