engine was located in a separate building from the elevator itself for fire safety.
Notice that the engine house itself is constructed of brick, while the elevator
and scale house are made of wood. All that grain dust in the elevator made it
highly susceptible to fire. So it was wise to house the engine, and any sparks
it might emit, in a fireproof building by itself.
After you complete your visit to the Engine House, return to the Floorplan
and move on to the “Boxcar.”