Folder A.3.1: Correspondence exchanged with parents, 1931-1943. Includes letters and press-cuttings regarding Coulson's visit to USA to lecture on pacifism, 1937, and some early photographs of Coulsons's parents, 1905-1906. Folder A.3.2: Correspondence exchanged with twin brother, John Metcalfe Coulson, 1934-1970. Coulson's letter of 27 October 1935 contains a spirited account of the incident when he gave up the set of rooms allotted to, and furnished by, him in Trinity to A.E.…