Mathias Baldwin built his first steam locomotive in 1832, with the assistance of a railroad mechanic named Andrew Vauclain. Five decades later, his son Samuel M. Vauclain joined the Baldwin Locomotive Works Company. Vauclain developed the compound locomotive in 1889, an achievement that changed the face of the railroad industry. He also engineered many engine prototypes, and performed developmental work on the balanced compound. A lifetime employee at Baldwin, he served as General Superintendent, Vice-President, President, and finally as Chairman of the Board, until his death in 1940. This catalog, which dates from 1900, shows Baldwin's full line of compound locomotive products and includes a discussion of their method of operation and maintenance. It includes technical specifications and other data. This version of the book has been slightly enlarged and reformatted for readability, but care has been taken to preserve the integrity of the original text.