He is best known for developing the celestial navigation method known as the Sumner line or line of position .
Thomas Hubbard Sumner ( 20 March 1807 -- 9 March 1876 ) was a sea captain during the 19th century .
Thomas Hubbard Sumner is best known for developing the celestial navigation method known as the Sumner line or line of position .
Thomas Hubbard Sumner ( 20 March 1807 -- 9 March 1876 ) was a sea captain during the 19th century .