Ministeam Atmospheric Engine from 1712

On this working model can be shown the function of the first atmospheric steam engine. With the heat of the spirit burner some water in the boiler starts boiling. The steam is blowing off by the check valve so there is no pressure in the boiler. As soon as a little bit of cold water is injected  into the steam with the spray bottler the steam condenses. A subpressure is coming up in the cylinder and the boiler. Now the atmosphere press down the piston and lift up the beam on the other end. The up and down of the beam operates the water pump connected on a chain deep in the mine.

Blacksmith Thomas Newcomen installed the first practical steam engine in a coal mine in Staffordshire, England in 1712. This was an atmospheric engine capable of pumping water out of mines at much greater depth than previously achieved. Former inventions by people such as Dennis Rapin 1690 and Thomas Savery 1698 were not successful.

Operation
The weight of the pump rods raised the piston to the top of its stroke, the cylinder being filled with steam and then water sprayed into the cylinder to condense the steam causing a vacuum. The pressure of the atmosphere then forced the piston down giving the engine its power stroke. On the other end of the beam was a chain connected to a water pump deep in the mine. The valves on early engines were operated by hand but this was very inefficient and the process was soon automated.