Minnesota Steamer Steam Roller - Traction Engine 

• A traction engine is a steam-powered tractor used to move heavy loads on roads, plough ground or to provide power at a chosen location. The name derives from the Latin tractus, meaning 'drawn', since the prime function of any traction engine is to draw a load behind it. They are sometimes called road locomotives to distinguish them from railway locomotives - that is, steam engines that run on rails.
•  Traction engines tend to be large, robust and powerful, but heavy, slow, and difficult to manoeuvre. Nevertheless, they revolutionized agriculture and road haulage at a time when the only alternative prime mover was the draught horse. 
• They became popular in industrialised countries from around 1850, when the first self-propelled portable steam engines for agricultural use were developed. 
• Traction engines were cumbersome and ill-suited to crossing soft or heavy ground, so their agricultural use was usually either "on the belt" - powering farm machinery by means of a continuous leather belt driven by the flywheel - or in pairs, dragging an implement on a cable from one side of a field to another. 

Approximate Size at 1/8 inch 

• L = 24.9 
• W = 6.7 
• H = 16.7