(Due to arrive Canberra 6.4.29)
My dear P.M.,
I attach lists of telegrams that should be taken off the official files, and either destroyed or kept in a personal file of your own. For your convenience I have had them done in separate lists, one being telegrams that have passed through the External Affairs Department (in Cypher C.O.1), and the other containing those telegrams that have gone direct between yourself and myself (in Cypher 'M', Cypher 'B' or Government Code).
All these telegrams are kept in personal files in this office.
I will put all telegrams that pass between us in the future in Cypher 'M' (of which I understand your Private Secretary has the only two copies) on to this private file, and no doubt you will do the same.
There should not be any other telegrams in the future of such a confidential nature passing through the External Affairs Department, now that we have Cypher 'M' in use between us.
I am, Yours very truly, R. C. CASEY