 Complete the following phrase:  The house was built in stages beginning sometime between 1818 and 1826. The rear ell of the house that Joseph Campbell sold to Henry Knox Thatcher in 1832 was probably built in that time; Campbell built the main house between 1826 and 1832. Thatcher, the grandson of American Revolutionary War general Henry Knox, served in the United States Navy for more than 50 years, rising to the rank of rear admiral. His most active period of service was during the American Civil War, where he commanded squadrons engaged in blockading Confederate ports, and directed the naval activities in the 