Here is the companion volume to Ken Cope's previous works on machine tools, carriage making machinery and cooperage machinery. Factories filled with the machinery described in the previous works, from the smallest drill presses to giant planers, could not have existed without a reliable and sufficient power source. The steam engine was that source, from the start of the industrial revolution to the general availability of electric power distributed from large, central generating stations in the early 20th century. Smaller size engines, made for farms and small industries such as cheese factories, greatly reduced the manpower required and therefore the cost of the final product to the consumer. The nearly 1000 illustrations show the development of the steam engine from 1800 to 1900 in a great variety of sizes, styles, and designs. Many designs shown proved impractical and were soon discarded; other designs such as the Corliss engine were made by scores of firms for scores of years. Along with the illustrations is a brief history of the individual maker, chronicling the various engines that each made.