The most famous Northumberland resident was Dr. Joseph Priestly, the English scientist most widely known for isolating oxygen. Priestly was a man considered by Thomas Jefferson to be one of the most brilliant minds of the late 1700s. While he was one of the foremost experimental scientists of his day, Priestly considered himself a minister and a teacher, he saw his experiments as a hobby to better understand God's universe. He was a Unitarian, rejecting the divinity of Christ and also supported the American and French revolutions. He believed strongly in separation of church and state and was not shy about expressing his opinions. He wote many articles and books about his somewhat controversial ideas both political and theological. Consequently, in 1790 or so, a mob in Birmingham, England, burned down his church and his home. As a son and a friend were already in the US pursuing real estate investments, Priestly left England and settled in Northumberland. He built this house with a well-equipped laboratory and continued to do experimental work.

This house had been through a number of reuses and cleaned out of all original furnishings. Some of the original furnishings have been returned and some materials have been replicated. Other items are appropriate to the period (1794 - 1804) but only speculation. They do help to convey the sense of what the house may have been like.