A rare find! This is only the fourth-known image of the extremely unusual O.S. Kelly triple-cylinder road locomotive. Other extant photos show these machines equipped with a horizontal drum for cable-plowing, beneath the boiler. Of all the U.S. engine manufacturers, only Kelly produced such a cable-plowing device. This shows the engine was used purely for hauling, without the drum mechanism. Interestingly, Frederick W. Wright is seen standing at the left of the platform of this engine, which is said to be hauling rock during construction of the Panama Canal.
Photo courtesy of the Wright family