Peter Ewart (14 May 1767 – 15 September 1842) was a British engineer who was influential in developing the technologies of turbines and theories of thermodynamics.
At the same time as acting as agent he was also trading on his own account as a millwright, enabling him to provide the complementary shafts, gears and other necessities to harness the power of the Boulton & Watt steam engines.
[1] In 1792, frustrated in administering the immature and, as yet, unreliable machinery,[citation needed] he left Boulton and Watt to work in partnership with Samuel Oldknow in a cotton bleaching and calico printing venture.
He became, along with John Dalton, a vice-president of the Manchester Literary and Philosophical Society and became active in the contemporary controversies about heat, work and energy.
A vocal advocate of the application of scientific knowledge in engineering, he was one of the founders of the Manchester Mechanics' Institute.