Actually folks, the pressure cooker goes back to the beginning of the 1700, and were usually refered to as a "bone digester". They were bronze, and although they had a steam vent, they didn't have a safety valve nor a pressure gauge,..., so they could "blow". The biggest problem seems to have been either a poorly cast piece of bronze with an air pocket, or the steam valve was so small it got clogged, and the pressure built up, or it was too small and not enough pressure was released.
It would be pretty easy to make with modern machining tools, and would work to cook food, but probably sorta heavy. Might make for a good demonstration at a historic site.
LD