Wheel_on_“Peggy,”_a_Lima_Shay_Geared_Steam_Locomotive_(SN_2172)
Steven Fine
CC-BY-SA 4.0
Science,_Technology_and_Engineering
Geralt
CC0 1.0
Clock gears
Przemek Pietrak
CC BY-SA 3.0
Stephenson’s_2-2-2_Patent_Locomotive_of_1837_-_crank_axle_cropped
Science, Technology and Engineering
CC BY-SA 4.0