Stock photography, photos: Panama Canal Mules Stock photos of The Panama Canal Mules are small electric locomotives that help centering the ships in the middle of the locks. The ships are propelled by their own power. Photograph: © Humberto Olarte Cupas Click for a larger image and more information Keywords associated with this stock photo: canal, commerce, business, currency, government, institutional, institution, authorities, authority, NugPanHoc, panama, south, latin, central, americas, america, tropical, tropic, caribbean, policy, politics, politic, governing, govern, states, state, legislative, legislation, palace, lawmaking, law, money, transaction, locks, lock, waterway, passageway, passage, channel, ship, vessel, transport, embark, boat, vehicle, voyage, downstream, upstream, sailing, sail, boating, vessels, clipper, barques, barque, watercourse, mule, tow, cable, pull, center, stabilize, locomotive, locomotor, electric