This is the first book to give a detailed treatment of every class of "super Power" stem locomotive built by Lima Locomotive Works, and to explain their use on the various railroads which bought them. The book explains the development of the Super Power concept, and how it was applied to nearly 700 of the finest steam locomotive in America in the period from the mid-1920s until 1948. It presents detailed data tables, photos, and history of each locomotive class railroad-by-railroad, with photos of all types.