The Rev. Joseph Priestley was an amazing guy who influenced many Founders, most notably Jefferson, J. Adams, and Franklin all of whom knew and interacted with him.
This is a video clip from CSPAN's Book TV on the most recent notable book about Priestley. We may know Priestley from our discussion of religion. But to the rest of the world he is known as the guy who discovered oxygen (which if you read the book you'll find out is a half truth).