This is a steam-powered tractor, which I photographed last August at my hometown’s annual festival, Threshing Days. It is a massive thing, full of detail, noise, and action.
The engine pictured here was being used for a threshing demonstration, which was how wheat was processed before combines were invented. A big flywheel on the engine was connected to a large belt, which powered the threshing machine. That machine separated the wheat like a modern combine does, but was supplied by farmers dumping wheat onto it.