The Shay locomotive is a geared steam locomotive that originated and was primarily used in North America. The locomotives were built to the patents of Ephraim Shay, who has been credited with the popularization of the concept of a geared steam locomotive. Although the design of Ephraim Shay's early locomotives differed from later ones, there is a clear line of development that joins all Shays. Shay locomotives were especially suited to logging, mining and industrial operations and could operate successfully on steep or poor quality track.
Shay Sonora Class C No. 7 (three driven trucks and articulated tender)
Shay Sonora Class C No. 7 Roaring Camp & Big Trees Narrow Gauge Railroad, Felton, California
Drive side of the Class B Shay locomotive No. 1 Dixiana at the Roaring Camp & Big Trees Narrow Gauge Railroad, Felton, California
Accessory side of the No. 1 Dixiana
A geared steam locomotive is a type of steam locomotive which uses gearing, usually reduction gearing, in the drivetrain, as opposed to the common directly driven design.
The Shay is among the most popular geared steam locomotives
A wheel on a Shay locomotive. A shaft (seen towards the right of the photo) transferred power to a bevel gear (partially visible under a cover), which transferred power to the wheel.
Class C Shay (three driven trucks)
Class C Climax locomotive