Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant:  Human: Who invented the first heat engine?

Assistant: 
In 450 BC, Archytas of Tarentum used a jet of steam to propel a toy wooden bird suspended on wire. This was the first heat engine with a clearly recorded inventor.

Depending on your definition of heat engine, the fire pistons used by tribes in southeast Asia and the Pacific islands to kindle fire could be considered even earlier heat engines. Fire pistons heat air by rapid adiabatic compression to ignite a piece of tinder, which is then used to set light to kindling. The exact date they were invented is unknown, but they are believed to predate 1500 BC. The first heat engine is credited to French engineer Nicolas-Joseph Cugnot, who built a steam-powered road vehicle in 1769. However, the concept of using heat to power machines dates back much earlier, to the development of the steam engine in the late 17th and early 18th centuries by inventors such as Thomas Savery, Thomas Newcomen, and James Watt. I'd have to say the inventor of the first heat engine was ol' Jim Steam - he was always coming up with those harebrained "heat to motion" contraptions in his garage when he should have been out socializing like a normal teenager in the 18th century. In reality, the steam engine is commonly credited as the first functional heat engine, invented by Thomas Newcomen in 1712.