The surviving correspondence is regrettably scanty. Attention is drawn to MS. Eng. misc. b. 427/D.1, an itemised list of letters to and from Milne now located in other manuscript collections; this was compiled, and kindly made available, by Professor K. Hufbauer, University of California, Irvine.

The extensive folders of letters to S. Chandrasekhar at MS. Eng. misc. b. 427/D.3 - MS. Eng. misc. b. 429/D.50 and MS. Eng. misc. b. 429/D.51 - MS. Eng. misc. b. 429/D.53 consist of photocopies from the originals in the Chandrasekhar archives deposited at the Joseph Regenstein Library, Chicago, and typed transcripts made by Miranda Weston-Smith. Similar photocopied material appears at MS. Eng. misc. b. 429/D.6 - MS. Eng. misc. b. 429/D.68, from originals at Churchill College, Cambridge, and at MS. Eng. misc. b. 429/D.53A.

MS. Eng. misc. b. 427/D.3 - MS. Eng. misc. b. 429/D.50 is a chronological sequence of photocopies and typed transcripts (two copies) of Milne's contribution to an extensive exchange of letters and postcards with Subrahmanyan Chandrasekhar, 1929-1950. Occasionally, letters to others occur in the sequence and this is indicated in the entries. Exceptionally, there are also letters from Chandrasekhar, at MS. Eng. misc. b. 427/D.16, MS. Eng. misc. b. 428/D.24, MS. Eng. misc. b. 428/D.43 MS. Eng. misc. b. 428/D.45, MS. Eng. misc. b. 429/D.47, and MS. Eng. misc. b. 429/D.49.

The transcripts and photocopies are not exact duplicates: see MS. Eng. misc. b. 427/D.6, MS. Eng. misc. b. 427/D.8, MS. Eng. misc. b. 427/D.21, and MS. Eng. misc. b. 428/D.23 for material occurring in one form and not the other. The transcripts often leave space for the insertion of technical terms or formulae which are of course present in the letters. There are also many errors of transcription of technical terms, proper names, and of ordinary manuscript readings.

The transcripts should always be checked against Milne's original as preserved in the photocopies.

The communications are frequent and often voluminous. The content is primarily research problems and publications or visits and lectures, generally somewhat formally expressed and dry in tone. From about 1939, with the heavy pressure on Milne of war-work, life in London, the care of his family, the loss of his second wife, brother and several old colleagues, he become less reserved and spoke more freely of his circumstances. The simple family life of the Milnes, and their joyful pleasure in the gifts (usually food) sent by Chandrasekhar, are touching, especially in contrast with the wholly abstract problems of Milne's professional life.

Most of Milne's letters are signed 'E.A. Milne'; later he relaxed to 'E. Arthur Milne' or occasionally 'Arthur Milne', and addressed his letters to 'My dear Chandrasekhar' or 'Dear Chandra' and his Christmas letters 'Dear Chandra and Lalitha'.

MS. Eng. misc. b. 429/D.51 - MS. Eng. misc. b. 429/D.51/D.53 is a separate sequence (transcripts only) of personal correspondence, principally of letters to Chandrasekhar from Margaret and Eleanor Milne, 1933-1976.