What is a Cornish engine and where did it originate?
A Cornish engine is a type of steam beam engine that originated in Cornwall. This region had no coalfield so all coal used for these engines was imported from outside the county.
Questions about Cornish engine
Short answers, pulled from the story.
How does a Cornish engine improve efficiency compared to early Watt engines?
Cornish engines achieve higher efficiency by shutting off the intake valve midway through the power stroke to allow steam expansion. This design captures greater energy proportions while reducing heat loss to the condenser compared to earlier models.
When were high-pressure steam principles first applied to Cornish engines?
Richard Trevithick devised the use of steam pressure above atmospheric pressure in the early 19th century. His later engines from the 1810s combined this high-pressure steam with sub-atmospheric principles to drive piston movement.
Where can you find working examples of Cornish engines today?
Crofton Pumping Station in Wiltshire contains two Cornish engines still operating as of the current era. The London Museum of Water & Steam holds the largest global collection of these historical machines.
What was the maximum duty achieved by late Cornish engines at Wheal Towan?
Samuel Grose improved duties to almost 80 million foot-pounds per bushel at Wheal Towan during the late 1820s. This represented a significant increase over the 30 million foot-pounds per bushel achieved by later Watt engines.