Alastair Denniston
Page 39
38. Government Code and Cypher School Report for 1940, TNA HW 14/11.
39. TNA HW 14/9.
40. Q/412, 23.11.40.
41. Q/412, 25.11.40.
42. Q/312, 24.11.40.
43. TNA HW 62/21 (previously called Q/2068, 13.12.41).
44. TNA HW 62/21 (previously called Q/2068, 14.2.41).
45. TNA HW 62/21 (previously called Q/2006, 25.2.41).
45. TNA HW 62/21 (previously called Q/2067, 17.3.41).
47. TNA HW 62/21 (previously called Q/2067, 18.11.41).
48. Sixta History, Section A, p. 16.
49. Q/3175, 5.2.41.
50. Q/3648, 8.2.41.
51. Q/516, 20.4.41.
52. History of I.E. (Intelligence Exchange), pp. 1–2.
53. N.S. Misc., 21.4.41.
54. Allied Sigint – Policy and Organisation, Chapter III, Part 1, pp. 84–5, TNA HW 43/75.
55. N.S. Misc., 8.3.41.
56. History of I.E., p. 8.
57. See Smith and Erskine.
58. TNA HW 62/21 (previously called Q/2006, 31.8.40).
59. People working on calculating machines were known as ‘computers’.
60. A network of observing stations had been set up covering Europe and the rest of the world. At certain agreed hours the observers at all stations made a note of the weather and incorporated it into a numerical international code message. This was typically of the form IIICLCMwwVhNhDDFWN, where III was the number assigned to the observing station; CL and CM were the types of low and medium cloud; ww was a 2-figure number describing the weather at the time of observation, from ‘00’ which meant cloudless to ‘99’ which meant heavy thunderstorm with hail; and so on for the other meteorological elements. This taken from an Autobiographical Sketch prepared by G.C. McVittie for the Royal Society of Edinburgh during 1976/77.
61. Interview in April 1983. See Cave Brown’s book on Menzies.
62. TNA HW 14/22.
63. Hugh Alexander, who became head of Hut 8 and remained in GCHQ after the war, wrote to the Director of GCHQ, Sir Clive Loehnis, in 1963. Margaret Rock had left GCHQ in 1963. She ‘bequeathed’ Hugh Alexander, as he went on to say in a covering note, ‘a fascinating series of memoranda from Dilly Knox written about 1940-41. Dilly was head of the original Enigma party and I suppose the senior cryptanalyst at the time. I enclose for your interest a letter written to the then Director [Menzies] … just so that you can appreciate how well behaved we analysts are nowadays!’ Loehnis’ reply: ‘and you of course can appreciate the advantages obtained from working with an enlightened and sympathetic Directorate’.
64. Jim Beach, ‘Origins of the Special Intelligence Relationship? Anglo-American Intelligence Co-operation on the Western Front, 1917-18’, Intelligence and National Security, Vol. 22, No. 2 (April 2007), pp. 229–49.
65. This involved talks about supply and defence programmes and staff plans. Churchill and Roosevelt had agreed in principle to the pooling of information on these subjects.
66. See Hinsley, Vol. 1, pp. 312–13.
67. Henry Stimson diary, 23–24 October 1940, Yale.
68. In an interview after the war, Sinkov said that the officer who greeted them was John Tiltman. In Currier’s account of the trip to England, he thought the officer was Humphrey Sandwith.
69. Accounts by Currier (Prescott Currier, ‘My ‘Purple’ Trip to England in 1941’, Cryptologia, Vol. 20, Issue 3, (1996), pp. 193–201) and by the head of OP-20-G, Commander Laurance F. Safford (L.F. Safford, in Dundas P. Tucker, ‘Rhapsody in Purple: A New History of Pearl Harbour – Part I’ (Greg Mellen (ed.), Cryptologia, Vol. 6 (1982), p. 216) claimed that the Americans brought two machines with them. Ralph Erskine has argued that based on the weight of the items shipped to Britain, only one machine could have been included (Ralph Erskine, ‘From the Archives. What the Sinkov Mission Brought to Bletchley Park’, Cryptologia, Vol. 27, Issue 3 (2003), pp. 111–18).
70. TNA HW 62/21 (previously called Q/2049, 6.5.43, AZ/393.
71. According to GCHQ, the Roll of Honour in a wood and glass cabinet now stands on the spot where the sherry cask was placed.
72. Sinkov and his group were shown the Bombe machines as their names appear in the Hut 11 Visitor Book, held today in the BP Archive. Apparently this was done with the express approval of Churchill.
73. Ralph Erskine, ‘What did the Sinkov Mission Receive from Bletchley Park?’, Cryptologia, Vol. 24, Issue 2 (2000), pp. 97–109.
74. TNA HW 14/45. AGD’s made it clear that his visit to Ottawa would only take place if he could avoid meeting Herbert Yardley, a former US cryptanalyst now working in Canada.
75. Denniston Report, TNA HW 14/45. See also Burke.
76. Pearson to Massey, 23 Sept. 1942, CSE doc. 000221-22.
77. Rowlett was the first of William Friedman’s original employees, hired for the Army’s Signal Intelligence Service (SIS) in 1930. From 1939–40, he had played a major role in solving a much more sophisticated Japanese diplomatic cipher machine, nicknamed ‘Purple’ by the US. Friedman and Rowlett also had crucial roles in protecting American communications during WW2. Working with the US Navy, they helped design the SIGABA, the cipher machine which was never solved by the Germans during the war. After the war, Rowlett eventually served in a number of senior roles in both the NSA and CIA.
78. TNA HW 14/45 ‘Notes on Conference Held August 14/15, 1941’.
79. United States Navy File of Correspondence with Department of State, 1919-1950, SRH-281, CCH Holdings, 74.
80. TNA HW 14/45 ‘Interrupted Conference with Commander Safford’, 18 August 1941.
81. Agnes May Meyer was born on 24 July 1889. She graduated from Ohio State University in 1911 and on 22 June 1918, she enlisted in the US Naval Reserve. After initially being assigned to the Office of the Chief Cable Censor, she on 18 June 1919 she moved to the Code & Signal Section with Naval Communications. After leaving the Navy, she was reemployed as a civilian and worked within MI-8, the ‘American Black Chamber’. She learned her trade at Riverbank Laboratories, where Willian Friedman had trained. In 1924 she joined the Research Desk of the Navy’s cryptographic section, OP-20-G. She married Michael Bernard Driscoll on 12 August 1925 and after WW2, she worked within the NSA until her retirement on 31 July 1959 at the age of 70. She died on 16 September 1971.
82. TNA HW 14/45 ‘Interrupted Conference with Commander Safford’, 18 August 1941, Para. 6.
83. Safford was informed that as soon as Driscoll’s work proved ‘in any way successful’ that GC&CS wanted to send out one of its best men. TNA HW14/45 ‘To Washington December 1 1941, ‘Your CXG 105 of 27.11.41’.
84. It seems that the Germans also considered a catalogue method. TICOM-I-38 – Report on Interrogation of Lt. Frowein of OKM/4 SKL III, On His Work on the Security of the German Naval Four-Wheel Enigma, June 21, 1945. Frowein had been assigned to check the security of the naval system in the summer of 1944 after the German naval authorities discovered a suspicious pattern of U-boat sinkings. In his interview with Allied investigators, he claimed that he had found a method to read the four-wheel Enigma using rather traditional methods of determining the fast-wheel, then, using a large catalogue of the other possible settings of a machine. As a result, the Germans ordered that only double turnover wheels be used in the fast position because his method would not work with a multiple turnover wheel in the fast position. However, his method demanded a very long crib, an enormous catalogue (some 4,000,000) entries and forbidding amounts of human and tabulator time if it was to be turned into more than a theoretical exploration.
85. National Archives of Canada (Ottawa), RG24, 12,324,s.4/cipher/4D.
86. Col. D.A. Butler (mI8) to DDMI(O), 27 December 1939 as above regarding remarks by AGD.
87. AGD memo of May 1943 in Virginia Military Institute, William Friedman papers, 110, SRH-153.
88. TNA HW 14/45 ‘Dispatch of Packages for US Authorities at Washington’, 28 August 1941.
89. TNA 14/45 ‘Dear Eddie�
��, 9 October, 1941.
90. Turing deduced that even if the wheel order and ring settings were known, it would take 72,800 hours of work to find a solution; National Archives and Records Administration (Washington), RG38 CHSG, Library, Box 104.
91. TNA HW 14/48, GC&CS memorandum of 16 August 1942.
92. TNA HW 14/74.
93. TNA HW 14/14.
94. TNA HW 14/16.
95. TNA HW 14/20.
96. Ibid.
97. TNA HW 8/23.
98. TNA HW 62/21 (previously called Q2006, 4.4.41).
99. TNA HW 62/21 (previously called Q2006, 7.11.41).
100. Allied Sigint – Policy and Organisation, Chapter III, pp. 109–10.
101. BP’s output was known as Most Secret Source and later, ULTRA.
102. TNA HW 62/21 (previously called Q/2006, 10.9.41).
103. The Typex machine was developed initially for the Air Ministry and following successful trails, 350 machines were ordered in June 1938, of which thirty went for trials with the Army. By October 1939, the War Office had ordered 207 machines while the Admiralty had ordered 630, of which around 350 were intended for use on ships. There was a shortage of machines throughout the war, given slow production. The total cumulative production of the two main models, Mk. II and Mk. VI was 500 by June 1940, 2,400 by the end of 1942, 4,000 by December 1943 and 5,500 by May 1944. The total built by the end of the war was around 12,000.
104. Q/3647A, 23.12.41.
105. Q2073, 19.1.42, Q/2065, 5.1.42.
106. Both the letter and Churchill’s minute appear in Hinsley, Vol. 2, Appendix 3, pp. 655–7. A facsimile of Churchill’s minute appears on p. xiii of Erskine and Smith. The letter and minute are in TNA HW 1/155. They are Crown copyright and are reproduced with the permission of the Controller of Her Majesty’s Stationery Office.
107. P. S. Milner-Barry, ‘“Action This Day”: The Letter from Bletchley Park Cryptanalysts to the Prime Minister, 21 October 1941’, Intelligence and National Security, 1 (1986), pp. 272–3.
108. Hinsley, Vol.2, p. 657.
109. Ibid., p. 26.
110. All were sent to the Foreign Office, the Admiralty – 4,526,; the War Office – 3,767; the Air Ministry – 4,212; MI5 – 1,166; MEW – 3,639; nine other departments and authorities received a smaller selection.
111. Kimball, Roosevelt and Churchill, Vol. 1, item C-32/1: letter from WSC to FDR, dated February 25, 1942
112. TNA HW 3/33.
113. Q/2022, 20.2.41.
114. TNA HW 62/20 (previously called Q/2000, 11.3.38).
115. NID Vol. 21, 1.3.47.
116. TNA HW 62/20 (previously called Q/2000, 18.6.36).
117. TNA HW 62/21 (previously called Q/2006. 23.1.42).
118. TNA HW 62/21 (previously called Q/2006, 10.9.41).
119. TNA HW 62/21 (previously called Q/2006, 9.9.41).
120. TNA HW 62/21 (previously called Q/2068, 24.9.41).
121. Allied Sigint – Policy and Organisation, Chapter III, p. 120.
122. TNA HW 62/21 (previously called Q2006, 1.4.41).
123. TNA HW 62/21 (previously called Q/2006, 30.1.42).
124. Ibid.
125. TNA HW 62/21 (previously called Q/2006, 4.2.42).
126. Head of ISOS and then combined ISOS and ISK from March 1944.
127. Head of Diplomatic Section until the move to Berkeley Street.
128. Responsible for communication lines and all GPO liaison with GG&CS.
129. TNA HW 14/27.
130. TNA HW 62/21 (previously called Q/2068, 6.2.42).
131. Welchman later told Robin Denniston that he had good reason to feel that his father was badly treated: ‘It was utterly disgusting – far, far worse than the way I was treated, which was bad enough.’ See Greenberg.
132. See Greenberg.
133. See Smith.
134. Paper written for Robin and ‘Y’ Denniston by Filby on 15 April 1981. He also made the point in a letter to Ronald Lewin on 11 April 1979.
135. Travis was formally appointed Director of GC&CS in March 1944 and knighted in June of the same year. GC&CS was renamed GCHQ and Travis remained as its director until 15 April 1952.
Chapter 5: Berkeley street
1. Filby letter to Robin Denniston, 15 April 1981.
2. Kennedy’s diaries are held by the library of the University of Sheffield. See Ferris.
3. Filby letter to Robin Denniston, 15 April 1981.
4. Kullback was recruited to SIS, based in Washington in 1930. He was responsible for breaking many Japanese codes, ciphers and machine systems during WW2. After the war he became Chief of the Research and Development effort at the NSA, retiring in 1962. See Oral History Interview with Kullback, NSA OH-17-82.
5. Sandwith attended the Pyry conference with AGD and Knox in Poland in July 1939.
6. Discussion paper presented by Captain H.R. Sandwith, 6 April 1942, NAC, RG24, 3806, NSS-1008-75-20. This is a rare contemporary description of British Sigint.
7. Little to Denniston, 18 April 1942, Canadian Security Establishment (Ottawa) doc. 300.
8. Shortly after returning from Britain, Little was promoted to lieutenant commander and appointed Director of Naval Intelligence.
9. AGD to Little with list attached, 6 June 1942, NAC, RG24, 8125, NSS-1282-85(1).
10. In this system, the code groups were enciphered by additives in the usual way, but the resulting superenciphered groups were then enciphered a second time using additives from the same book, but with a different starting point. This method enabled the additive book to produce several million ‘double additives’. (A complete book of Floradora additives covered a range from 0000 to 9999 (page 00, row 00 to page 99, row 99, with six groups of five additives in a row). The first half of a book (pages 00 to 49) was used for encipherment, while the second half (pages 50 to 99) covered decipherment. The second part consisted of the digital compliments of the first half (so that additive group 43642 in the first half would be 67468 in the same relative place in the second), to allow addition rather than subtraction to be used when deciphering messages. Unusually, addition was chosen for both operations because it gave rise to fewer errors by the cipher clerks.)
11. ‘Report of Cryptographic Mission 0 Maj. Sinkov 1941’, 8-10 (HCC, Box 1296, Nr. 3873). GC&CS Report, 1940, German diplomatic section, TNA HW 14/11.
12. Head of the German Diplomatic Section from 1939 to 1942 when she left due to ill health.
13. GC&CS (civil section), ‘Report on present position of legibility of foreign ciphers’, 25 May 1942, TNA HW 14/38.
14. German diplomatic section minute, 8 August 1942, TNA HW 14/48; AGD memo of 31 October 1942, para 24 TNA HW 14/45; AGD to Tiltman, minute of 8 March 1942, item 7, TNA HW 14/4. According to Filby: ‘Denniston received a message from the British Consul in Lourenco Marques, the capital of Portuguese Mozambique on the east coast of Africa. The German Consul’s primary job was to report shipping passing the port. Denniston received a letter and a pouch. “Dear Alastair”, the message read, “this was dropped in my letter box by a sailor, thinking it was the German Consulate. Are the contents of any use to you?” Remarkably, they contained the daily keys for the next three months which enabled the section to work out the additive lines used in every message sent by the German Foreign Office. With the help of SIS at Arlington Hall, the system was effectively broken. The main break was based on a message from Berlin to Dublin that said that new instructions for the use of ‘Floradora’ between Berlin and Dublin were being sent in a message which would be like an OTP message. The new ‘Floradora’ system would then become the principal form of communication between the two centres. Further information about the operation of the system gave the Section all it needed to break ‘Floradora’.
See also Phillips.
15. NSA declassified document (SC)A6-1(8)(C) A-N Collab.
16. Tony Kendrick had been an early recruit to Dilly Knox’s team at BP and was thus, an experience cryptanalyst. In 1942, he was sent to Canada to ta
ke over the running of Canada’s Examination Unit from another BP veteran, Oliver Strachey.
17. A junior commissioned officer rank in the US Navy.
18. Hastings was SIS’s Head of Codes in Washington from June 1941. He returned to Britain in 1943 and from May he was Head of the Diplomatic section at Berkeley Street. AGD appointed him Deputy Director in March 1944.
19. Mr Friedman’s Report of his activities in England during the period Apr.23–June 13, NSA Report Ref ID:A4146452.
20. Informal memorandum by Commander Denniston outlining his original concepts of the American liaison, 21 May 1943: Liaison Activities in the UK, p. 16, NARA RG 457, Entry 9002, SRH 153.
21. Informal Memorandum by Cmdr. Denniston Outlining His Original Concept of the American Liaison – May 1943 and handed to Colonel Alfred McCormack.
22. Berkeley Street, p. 59 in ‘Conversations with Denniston’: ‘Col. McCormack’s Trip to London, May-June 1943’, NARA HCC Box 1119, No.3600.
23. NAC, RG2(14), 5758, DC135.
24. Kindly provided to the author by the Denniston family.
25. The Section graded and annotated diplomatic translation as follows: Explanation of reference: e.g. My No. 249 [Departmental Note. Issued as our BJ No. 105279] or [Departmental Note. Not yet decipherable]. Textual Comment: e.g. [two groups indecipherable] or [remainder not received]. Elucidations: e.g. To M. Anastasiadis’ [Departmental Note: The new Foreign Under-Secretary]. These were normally inserted by the submitting section (in the third case sometimes initiated by D. and R).