The correspondence includes a letter from Guthrie to Victor Purcell, agreeing to join the group and expressing concern about the increasing size of the 'Science and Civilisation in China' volumes; copy of a letter from Purcell to Guthrie advising him that his comments would be passed to Joseph Needham; Joseph Needham's reply to Guthrie addressing the query relating to growing volume size and discussing collaboration on the project; Joseph Needham's draft of the letter to Guthrie.