by Alastair Denniston- Code-breaking From Room 40 to Berkeley Street
9. Rotter and Hope had better claims to be the Admiralty candidate but both were moving on. Other civilian members of Room 40 were keen to return to life outside the Service.
10. Curzon to Walter Long, First Lord of the Admiralty, 24 March; minute by Sinclair, 28 March; minutes of conference held at the Foreign Office, 29 April1919, TNA, ADM 1/8637/55.
11. TNA HW 3/35. Notes of Formation of GC&CS TNA HW 3/33.
12. It seems highly unlikely that the Admiralty would have accepted a non-Room 40 candidate.
13. See Alice Hay.
14. Hay’s OBE was actually gazetted, i.e. announced in a Government publication.
15. Establishment of GC&CS covered in TNA HW 3/34 and ADM 1/8637/55.
16. Edward Wilfrid Harry Travis was born on 24 September 1888 in Kent. He was known as Wilfrid to his family and ‘Jumbo’ to friends due to his rather rotund build. He joined the Royal Navy in 1906 and passed to Paymaster in 1909. On the first day of WW1 he was posted as Secretary’s Clerk to the Commander-in-Chief, Admiral Sir John Jellicoe, on the flagship HMS Iron Duke. His 1918 report signed by Jellicoe refers to his zeal, ingenuity and ability. He was lent to the Admiralty’s Signal Division in 1916 at Jellicoe’s request ‘for the compilation of cyphers for use in the Fleet’. It is said that he got this posting because he had personally broken Jellicoe’s ciphers to show their vulnerability.
17. TNA HW 12/1-3.
18. Code and Cypher School memo by Lord Curzon (C.P. 3105), 3 July 1921 (Curzon papers, Mss Eur/ F.112/302).
19. The ‘Geddes Axe’ refers to proposals for spending cuts in Britain, made by Sir Eric Geddes who had been Director-General of Munitions and Railways in WW1, and later Minister of Transport (1919–21). In 1921, He chaired a committee which would suggest reductions in public expenditure of £86 million. The eventual reduction in the 1922 budget was £64 million and Geddes specifically targeted the armed forces, whom he had successfully portrayed as profligate spenders
20. By the late spring of 1923, it was decided that Sinclair should take over from Cumming, whose health was failing, as Chief of SIS in September of that year. Following Cumming’s death on 14 June, he took up his new post on 3 September. Sinclair was a bon vivant whose nickname ‘Quex’ was given to him as a young man and taken from a play by Arthur Pinero called The Gay Lord Quex, in which the hero was described as ‘the wickedest man in London’ who subsequently became a reformed character. According to Jeffrey’s Official History of MI6, he was ‘one of the most imperturbable of men’ and was ‘always appreciative of good service in a subordinate’. He had a stormy private life and had violent rows with his wife in the captain’s cabin while serving as captain of HMS Renown. Much to his embarrassment he was divorced in 1920, soon after becoming naval aide to the King (Andrew, Secret Service, p. 295 and Sinclair service record, TNA ADM 196/43, p. 368, ADM 196/53, p. 199).
21. See Appendix 2 for GC&CS staff list for 1919 (Curzon to Lee, 25 April; and reply 23 May; minute by Lee, 2 May 1921, TNA, Foreign Office 366/800).
22. Report of Inter-Service Directorate Committee, 9 April 1923; note on ‘control of interception’, n.d. [c. 1924] TNA, WO 32/4897.
23. The wartime WOGs had in effect become local Sigint organisations, capable of providing a service to the local commander.
24. The Government Code and Cypher School: A Memorandum by Lord Curzon, CAB 24/126.
25. DENN 1/3.
26. Sinclair to Crowe, 3 November 1923, TNA, Foreign Office 366/800.
27. See Jeffrey, pp. 213–14. His source referenced as ‘Denniston, “Government and Code Cypher School”, 49’.
28. GC&CS ‘Historical Notes’.
29. TNA HW 42/1, HW 42/2, HW 42/30.
30. TNA HW 62/20, HW 62/21.
31. H.C. Kenworthy , ‘A Brief History of Events Relating to the Growth of the ‘Y’ Service’, 11 June 1957, TNA HW 3/81.
32. See Clarke’s memoirs at Churchill College and ‘Naval Section 1927-1939 – Mr W. Bodsworth’s account’, n.d., TNA HW 3/1.
33. Menzies was born on 30 January 1890 in London. He joined the Life Guards in 1910. He served on the Western Front and was decorated for gallantry before being gassed. He was then appointed to a security intelligence position at GHQ and by 1918 he was a liaison officer between the Directorate of Military Intelligence and MI1(c). While in principle a member of the army, who paid his wages, he was a part of ‘C’’s organisation and formally transferred from the War Office to the SIS payroll on 1 April 1923 as Head of Military Section IV. He represented SIS in collaboration with the main French intelligence agency in the 1920s, the Deuxième Bureau. Menzies was fluent in French and this would stand him in good stead in the years leading up to WW2.
34. DENN 1/4.
35. A One-Time Pad disguises the numerical codegroups of a diplomatic or military code by adding them to a long numerical key. The German diplomatic system consisted of pads of fifty numbered sheets, each with forty-eight five-digit groups, distributed in eight lines of six groups. All the digits on each sheet were random, no sheet was duplicated and each sheet was used only once. For example, the code 3043 9710 3964 3043 might have the key 7260 0940 5169 4174 added to it yielding 0203 9650 8023 7117 (no carry over or tens digits are carried or written down so for the first digit in the example above, 3+7 = 10 becomes 0).
36. A slip is a sheet of paper containing a short description of a particular code or cipher system with details of its external characteristics (e.g. call-signs, preamble, etc.), users and period of currency.
37. John Tiltman could lay claim to being one of the greatest cryptologists of his generation. Born in 1894, he was offered a place at Oxford when he was 13 but as his father had recently died, he left school at the end of 1911 to become a teacher. Following a distinguished career in WWI, he was sent on an elementary Russian language course which would change his life. On 1 August 1920, he was seconded for two weeks to GC&CS to help with a backlog of translation work. He took to decryption work so well that the War Office posted him to GC&CS initially for a year but he never returned to conventional regimental duties. A biography of Tiltman is long overdue and his accomplishments are too numerous to cover here. He continued working for GCHQ after the war until his retirement in 1964. He was immediately asked to join the NSA as he was living in the US, and served until 1980 when he was 86! He was honoured by the directors of GCHQ and NSA for his ‘uncountable contributions and successes in cryptology’ and for setting ‘exemplary standards of professionalism and performance in cryptology’.
38. The correct spelling is Vetterlein but official British Government documents of the day use Fetterlein.
39. TNA HW 25/6. Some authors have mistakenly credited ‘Dilly’ Knox with purchasing the machine in the 1920s.
40. Dorothy Denniston’s pass, providing access to the Anglo-French decryption unit at the Paris Peace Conference, is on display at Bletchley Park.
41. ‘Experience 1920-1939’, Brigadier John Tiltman, NSA website, DOCID: 3868631.
42. DENN 1/4.
43. Ibid.
44. DENN 1/4.
45. A small Metropolitan Police wireless unit was initially based in the attic at Scotland Yard and, from the mid-1930s, in the grounds of the Metropolitan Police Nursing Home at Denmark Hill, South London.
46. This was the commercial Enigma with (IIRC) rewired rotors and could be solved using the notes left by Hugh Foss, who had investigated the commercial machine.
47. The steckerboard was in effect a plugboard at the front of the Enigma machine which had twenty-six sockets, one for each letter of the alphabet. By the 1930s, ten pairs of letters were pugged together adding 150.7 million, million additional possible configurations to the machine.
48. TNA HW 62/21, 62/20, (previously called Q/2000).
49. TNA N.I-XV – GC&CS Naval Sigint History, Vols. I–IV (previously Documents Relating to Naval Section, 1915-1939, No. 21, 16.11.27).
50. TNA HW 62/19 (previously called Q/2000, paper dated ‘End of 1927’, par
a. 4).
51. TNA HW 62/19 (previously called Q/2000, 29.4.32).
52. TNA HW 62/10 (previously called Q/2062, 21.6.32).
53. TNA N.I-XV – GC&CS Naval Sigint History, Vols. I–IV (Naval Special Intelligence, 1.10.32, also NID Vol. 26, 9.12.36).
54. TNA HW 62/19 (previously called Q/2064, 21.6.32, 7.11.34).
55. TNA HW 62/21 (previously called Q/2020, 11.1.38).
56. A series of figures or letters (or a group or single unit of such) which is added non-carrying figure by figure or letter by letter to the figures or letters of code groups in the process of re-enciphering or to the letters of plain language in the process of enciphering, and subtracted from the cipher in the processes of stripping and deciphering.
57. TNA HW 62/21 (previously called NID 00714/39 (Q/2000. 30.6.39)).
58. TNA HW 62/21 (previously called Q/2000, 1.7.38).
59. TNA HW 62/20 (previously called Q/2000, 20.11.36).
60. TNA HW 62/21 (previously called Q/2000, 17.7.39).
61. TNA N.I-XV – GC&CS Naval Sigint History, Vols. I–IV (previously Documents relating to Naval Section, 1915–1939, No. 1, pp. 8).
62. TNA N.I-XV – GC&CS Naval Sigint History, Vols. I–IV (previously Documents relating to Naval Section, 1915–1939, No. 65, 17.10.38).
63. TNA HW 62/21 (previously Q/2064, 14.2.38, W.F. Clarke to AGD in a covering letter enclosing letter from one of his staff, Lieutenant Commander M.G. Saunders).
64. TNA HW 62/10 (previously Q/2064, 28.4.38, pp. 13, 15).
65. DENN 1/4.
66. E.R.P. Vincent, unpublished memoirs, pp. 77–8.
67. Peter Twinn was the first mathematician to be recruited by GC&CS between the wars and arguably, was the first person in Britain to break a message encrypted by an Enigma machine which included a plugboard.
68. BP had been bought by Sir Herbert Leon, a wealthy London stockbroker and his second wife Fanny around 1882, along with 581 acres of land. They had added servants’ and domestic quarters and further extensions. The mansion was described by one former GC&CS employee as ghastly and another as indescribably ugly. Apparently, the Leons travelled abroad extensively, would see some architectural feature which they liked and would return home with a sketch of it for their builders to implement. Sir Herbert died in 1926 and his wife carried on running the estate until her death in January 1937. Sir Herbert’s heir, his son, George, duly sold off the bulk of the estate at auction by splitting it into lots. Lot 1, which initially didn’t sell and consisted of 55 acres including the mansion, stable yard and lake, was bought by a consortium of local builders and developers headed by Captain Herbert Faulkner.
69. Property transfer documents from Land Registry (Leicester Office), Bletchley Park, Title no. BM677; Sinclair’s will, 4 Nov. 1938.
70. HW 3/83 (Josh Cooper Reminiscences, written in 1975).
71. The Munich Agreement was a settlement reached by Germany, Great Britain, France, and Italy that permitted German annexation of the Sudetenland in western Czechoslovakia.
72. Conduct of Work No. 46, 15.11.39. ‘Army Interception History, Chapter II, pp. 1–3’.
73. See Kahn.
74. System by which the starting position of the Enigma machine is encrypted or concealed before being sent to recipients of specific encrypted messages.
75. The Reichswehr was the German Army from 1919 until 1936, when it was renamed the Wehrmacht.
76. TNA HW 25/12.
77. Ibid.
78. Ibid. See also Foss, ‘Reminiscences on Enigma’ in Erskine and Smith, p. 45. Foss joined GC&CS in 1924 and was tasked with examining an Enigma machine in 1927 by Travis.
79. Knox memo, 13 January, 1939, TNA HW 25/12.
80. ‘The breaking up of the German cipher machine “ENIGMA” by the cryptological section in the 2nd Department of the General Staff of the Polish Armed Forces’, S.A. Mayer, memo, 31 May, 1974, TNA HW 25/12.
81. DNI at this time was Rear Admiral John Godfrey. A number of authors who wrote about this meeting years later, mistakenly believed that it was not Sandwith who attended the meeting, but the future head of MI6 Stewart Menzies, in disguise as a distinguished British professor.
82. The ring around each Enigma wheel had 1–26 (Army/Air Force) or A–Z (Navy) embossed on it and could be set to any one of twenty-six positions. Thus there were 26 x 26 x 26 = 17,576 possible ring settings.
83. TNA HW 25/12.
84. See Rejewski, ‘How Polish Mathematicians Deciphered the Enigma’.
85. TNA HW 25/12.
86. The task was assigned to a team led by John Jeffreys and a machine was built to punch out the holes. It was a monumental task and apparently a small party was held to celebrate the punching of the two-millionth hole. The Poles were doing the same work by hand with razor blades! The Zygalski sheet method was called the Netz method (or just Netz) at BP and because Jeffreys led the work, some authors have subsequently confused the Netz with another perforated-sheet method which he developed. The Jeffreys sheet method was actually a catalogue of the effect of two wheels and the reflector. The Netz method was reinvented by Gordon Welchman in his early days at BP.
87. The German military ciphers adopted a new indication system on 15 September 1938 which the Poles attacked with their bomba machines. The reference to Mrs B.B., who has never been identified, refers to Knox’s failure to deduce the wiring to the entry disc. In (c) ‘machine’ probably refers to the bomba, SSD to Sicherheitsdientst (the intelligence service of the Nazi party), and O.S. & n.s. to old and new indicating systems used before and after 15 September 1938. Knox’s reference to Polish failure (d) is harsh as the Poles were working with limited manpower and resources. This was stretched further when the German Enigma operators were given two additional wheels, thus increasing the number of wheel configurations from six to sixty.
88. Up until May 1940, the sending operator would choose a message setting and encrypt it twice with the daily setting of his machine. The resulting six encrypted characters would appear as the first six characters in the body of the encrypted message.
89. AGD is probably referring here to Dunderdale.
Chapter 4: Bletchley Park
1. TNA HW 3/1.
2. Foreign Office 366/1059.
3. Due to a shortage of office space at BP, Elmers School, a private school for boys located nearby, had been acquired for the Commercial and Diplomatic Sections.
4. TNA HW 14/1.
5. Knox to AGD 29 September 1939, TNA HW 14/1.
6. Welchman was asked by Knox to analyse Call Signs and Discriminants. The former revealed the designation of the sender and intended recipient of the message; the latter revealed the designation of the specific Enigma setting or key that had been used to encrypt the message. See Welchman and Greenberg.
7. Enigma settings were known as ‘keys’ at BP.
8. See Welchman.
9. TNA HW 14/7.
10. Official History of MI6, p. 329.
11. Major General Sir Stewart Menzies served as head of SIS/MI6 until 1952. He died on 28 May 1968 at the age of 78.
12. TNA HW 14/2.
13. No copy of Welchman’s original proposal to Travis has survived but he documented it again in his own book and other writings. See Welchman, and Greenberg.
14. See Greenberg.
15. TNA HW 3/107.
16. TNA HW 14/3.
17. Ibid.
18. Ibid.
19. The ‘Phoney War’ was the name given to the period of time in WW2 from September 1939 to April 1940 when, after the blitzkrieg attack on Poland in September 1939, there was little military engagement between opposing forces in Europe. The term ‘Phoney War’ was first used, allegedly, by an American senator called Borah. Winston Churchill referred to the same period as the ‘Twilight War’ while the Germans referred to it as ‘Sitzkrieg’ – ‘sitting war’.
20. Admiralty Hydro and Ultra series, 5.1.40–2.7.40.
21. See Chapter 3, Note 78.
22. A Watch wa
s like a shift in the modern workplace.
23. SIS Communications was known as MI6 Section VIII and was based at Whaddon Hall in the village of Whaddon during WW2.
24. TNA HW 3/33.
25. IV LN Versuchs or Luftnachrichtenversuchsregiment.
26. TNA HW 62/21 (previously called Q/2006, 29.9.40).
27. TNA HW 62/21 (previously called Q/3261, 29.12.39).
28. TNA HW 62/21 (previously called Q/2006, 28.5.40).
29. GC&CS Naval Sigint History, Vol. IV, pp. 29–41. Also see Batey.
30. The Foreign Office officials were Miss Emily Anderson, who would later work at Berkeley Street, and her chaperone.
31. TNA HW 62/21 (previously called Q/2006, 22.7.40).
32. TNA HW 62/21 (previously called Q/2065 13.11.40).
33. Q/3213, 1.2.42.
34. Q/2006, 20.5.41.
35. TNA HW 62/21 (previously called Q/2022, 11.4.40).
36. TNA HW 62/21 (previously called Q/2006, 6.10.40).
37. The French party included: Capt. Roger Baudouin, at BP 12 June 1940 to 9 March 1942 then Liaison Officer between Free French Sigint and BP. Died in April 1944 in an aircraft accident while en route to Algiers (by then a Commandant). Wartime pseudonym R. Baldwin; Capt. Bracquerie (believed to have returned to France at some point after the Armistice); Lt. Graverand (returned to France after the Royal Navy attack on the French Fleet at Mers-el-Kébir); Capt. Hutter (believed to have returned to France after the Armistice); Kiefe (believed to have joined the Free French in London summer 1940); Capt. Felix Meslin (at BP 27 April 1940 – 9 March 1942, then Wavendon, then London. Wartime pseudonym F, Miller); Lt. André Mirambel (at BP 27 April 1940 – 9 March 1942, then Wavendon, then London. Wartime pseudonym M.M. Merry); De la Pierre (returned to France after the Royal Navy attack on the French Fleet at Mers-el-Kébir); Roger (Believed to have joined the Free French in London summer 1940); Lt. Jean Emile Royer (arrested in Nov 1940 for a major security breach – no further information. Interned. ‘C’ ruled in September 1944 that he was not to be expelled to France until after VE Day); Lt. Claude Schaeffer (at BP 1940. Officially joined the Free French Naval Force in London. At BP 27 April 1940 – 9 March 1942, then Wavendon, then London. Brought his whole family to the UK so no pseudonym); Lt. Marc Vey (at BP 27 April 1940 – 9 March 1942, then Wavendon, then London. In 1944 replaced Baudouin as Free French liaison with BP. Wartime pseudonym M.A. Volney).
