Concept
A beam engine is a type of steam engine where a pivoted overhead beam is used to apply the force from a vertical piston to a vertical connecting rod. This configuration, with the engine directly driving a pump, was first used by Thomas Newcomen around 1705 to remove water from mines in Cornwall. The efficiency of the engines was improved by engineers including James Watt, who added a separate condenser; Jonathan Hornblower and Arthur Woolf, who compounded the cylinders; and William McNaught, who devised a method of compounding an existing engine. Beam engines were first used to pump water out of mines or into canals but could be used to pump water to supplement the flow for a waterwheel powering a mill. The rotative beam engine is a later design of beam engine where the connecting rod drives a flywheel by means of a crank (or, historically, by means of a sun and planet gear). These beam engines could be used to directly power the line-shafting in a mill. They also could be used to power steam ships. The first beam engines were water-powered and used to pump water from mines. A preserved example may be seen at the Straitsteps Lead Mine in Wanlockhead in Scotland. Beam engines were extensively used to power pumps on the English canal system when it was expanded by means of locks early in the Industrial Revolution, and also to drain water from mines in the same period, and as winding engines. The first steam-related beam engine was developed by Thomas Newcomen. This was not, strictly speaking, steam powered, as the steam introduced below the piston was condensed to create a partial vacuum thus allowing atmospheric pressure to push down the piston. It was therefore called an Atmospheric Engine. The Newcomen atmospheric engine was adopted by many mines in Cornwall and elsewhere, but it was relatively inefficient and consumed a large quantity of fuel. The engine was improved by John Smeaton but James Watt resolved the main inefficiencies of the Newcomen engine in his Watt steam engine by the addition of a separate condenser, thus allowing the cylinder to remain hot.
