Conversation so far:
who invented the first steam engine and when
An Englishman is usually credited with inventing the first steam engine. In 1698, Thomas Savery patented a machine that could effectively draw water from flooded mines using steam pressure.
did inventor Thomas Savery work with or get inspiration from anyone
Thomas Savery used principles set forth by Denis Papin, a French-born British physicist.
what did Denis Papin make
Denis Papin invented the pressure cooker.
does the pressure cooker use steam power
The pressure cooker, invented by the physicist Denis Papin, works by expelling air from the vessel, and trapping the steam produced from the boiling liquid inside.

Question: when was it invented
Self-contained rewrite: when was the pressure cooker invented