Shay locomotive

The Shay locomotive is a geared steam locomotive that originated in North America and was used mainly for logging, mining and industrial work, where its design let it run on steep or poor-quality track. It follows the patents of Ephraim Shay, a Michigan logger and inventor, whose prototype engine Lima Locomotive Works built in 1880. Lima built about 2,770 Shays in four classes between 1878 and 1945, and Willamette Iron and Steel Works and a few other firms made similar locomotives after the basic patents expired. A vertical two- or three-cylinder motor on the right of an offset boiler drove every axle through shafts and bevel gears with no side rods, so every wheel that carried weight also developed tractive effort. Shays were often called sidewinders or stemwinders, and many were exported to about 30 countries.