Seizing the Enigma (54 page)

100
“because of the delightful”: A. G. Denniston, 59.

100
Knox attack on Italian Enigma: Fitzgerald, 254; Denniston, 60.

100
Knox and
la méthode des bâtons:
implied in photo 12 in Kozaczuk. See also Deavours, “La Méthode des Bâtons.”

101
1937 success: Hinsley, 1:54.

101
plugboard; A. G. Denniston, 60.

102
creation of O.I.C.: Beesly,
Very Special Intelligence
, 9–23; Hinsley, 12–13; Denning, 270–72.

102
first time since 1928: CLKE 3, no. 40.

102
German subsection: Hinsley, 1:55.

103
Bletchley Park: R. A. Denniston, 114; D. C. Low,
The History of Bletchley Park and Mansion
(n.p., 1963). For Leon:
Debrett’s Peerage and Baronetage
(1985), B536.

103
Schleswig-Holstein:
Germany, Auswärtiges Amt,
Documents on German Foreign Policy 1918–1945
, ser. D, 6:471–72, 807; 7:195–96; Bertil Stjernfelt and Klaus-Richard Böhme,
Westerplatte 1939
, Einzelschriften zur militärischen Geschichte des Zweiten Weltkrieges, 23 (Freiburg: Rombach, 1979), 79.

The material on Turing is from Andrew Hodges, passim, and from Good, 3–4, 5. Information on the Turing bombe is from Andrew Hodges, 176–85; Deavours and Ellison interviews; Deavours and Krüh, “Turing Bombe”; and Gaj, 148–60. Material on the bombes is from various interviews. Material on the diagonal board is from Welchman,
Hut Six Story
, 81–83, 295–309, and Deavours and Ellison interviews. Information on Welchman is from Milner-Barry and Tischler interviews; on de Grey, from Filby, 275; on Adcock, from Morris interview and
Dictionary of National Biography, 1961–1970
, 6–7; on Alexander, from Milner-Barry interview, Milner-Barry, “C.H. O’D. Alexander,” and Good, 3, 5–6; on Milner-Barry, from Milner-Barry interview and
Who’s Who, 1990;
on Forster, from Forster interview and
Who’s Who, 1990.

105
Polish evacuation: Kozaczuk, 69–80; Watt, 7–9.

109
bright ideas: Twinn interview.

110
“then there is”: “On Computable Numbers, with an Application to the Entscheidungsproblem” (1937), reprinted in Martin Davis,
The Undecidable
(Hewlett, N.Y.: Raven Press, 1965), 148.

116
first bombe: Hinsley, 1:184; 3:2:954; Welchman, “From Polish Bomba,” 107, says September; Welchman,
Hut Six Story
, 147, for “Agnes”; Monroe interview.

117
Hut 8: Wylie, Good interviews.

117
ISK: Lewin, 118–19.

All the information in this chapter is from PG 30030, ADM 199/123; Rottmann and Masanek interviews; and Becker letter.

Information on the Polish cryptanalysts in Algeria and southern France is from Bertrand, 107,117,140–42; and Braquenié interview in Kozaczuk,
Geheimoperation Wicher
, trans. Theodor Fuchs, ed. Jürgen Rohwer (Koblenz: Bernard & Graefe, 1989), 322. Enciphering the solutions in Enigma is from Kozaczuk,
Enigma
, 87; and R. A. Denniston, 114. Information on the threats to the security of Enigma solutions is from Bertrand, 156–58, 184–85; and Kozaczuk,
Geheimoperation Wicher
, 203–6, 210, 216–17, and 334–37.

All details of the capture of April 26, 1940, are from ADM 199/476. I believe this is the Vorpostenboot VP2623 mentioned in Hinsley, 1:163, 336. The
Kriegsmarine
did not have a Vorpostenbootflotille 26, and no patrol boat number VP2623. Though a contemporary document refers to VP2623 as the source of cryptographic documents—probably Hinsley’s source—the Royal Navy’s War Diary for Home Commands (ADM 199/2203) for April 26, 1940, mentions only the trawlers and says nothing about patrol boats. Moreover, Hinsley says that VP2623 had been looted, as was the
Polares.
Nothing was found about any captures or sinkings of ships on the date in question in the following German navy war diaries: Commanding Admiral Norway, Admiral of Norwegian West Coast, Admiral of Norwegian North Coast, Admiral of Norwegian Polar Coast, Wehrmacht Command South Coast Norway, Coastal Commander Denmark, Commandant in Section West Coast Denmark.

On the
Glorious
, the antecedent events, and the effects of its loss: Beesly,
Very Special Intelligence
, 37–38; Hinsley, 1:141; Winton,
Carrier Glorious
, 165–82; Roskill,
War at Sea
, 1:194–96; Hinsley interviews. Ian Fleming’s idea of seizing an Enigma from a German air rescue ship and the ensuing events are from ADM 223/463:38-39 and Wilson.

Material on Hinsley is from Hinsley interview and from Andrew, “F. H. Hinsley”; on Haines, from Hinsley, 1:274; Beesly,
Very Special Admiral
, 169, 193; CLKE 3, p. 5; and Wylie interview.

131
rotors VI and VII: Hinsley, 3:2:957. He states at 1:336 that three rotors were captured from the U-33, but that one of those captured may already have been known.

132
Herivel tip: Herivel interview; Welchman,
Hut Six Story
, 98–99; Welchman, “From Polish Bomba,” 99, 107.

133
“Royal Flags Wave Kings Above”: Monroe interview.

133
May 22, 1940: Hinsley, 1:109, 144.

134
83 percent: Rejewski, “Remarks on Appendix 1,” 81.

134
hundred keys: Hinsley, 1:493; Bertrand, 79.

134
“Concerning directive”: Bertrand, 285.

136
encouraged Naval Section: Hinsley interview.

138
Radio Cipher H, Dockyard: Morris, 115–16; M.Dv. Nr. 103.

147
“the recent recrudescence”: Winston S. Churchill,
Blood, Sweat, and Tears
(New York: Putnam’s, 1941), 411.

147
atmosphere not disheartened but industrious: Wylie and Hinsley interviews.

Information on the Tribal class destroyers and the
Somali
is from Brice, 7,15–18, 228–34; Peter Hodges, 6–7, 10, 53; Wellings, 47, 53, 57, 58, 60. All details of the raid on Norway are from DEFE 2/142, which includes some information deleted from Tovey; MA:M8i5/472i9:4.3. [19411:1435; interviews with Warmington, Stuart-Menteth, Low, and Harper-Gow; and Roskill,
War at Sea
, 1:341–342. On Warmington: Warmington interview;
Who’s Who, 1990; Burke’s Peerage and Baronetage
103 (1963), 2505.

Information about Wylie, Good, Brett-Smith, and Lever and on life at Bletchley is from Good, 7; and from interviews with Good, Hilary Hinsley, Barbara Eachus, and Mavis Batey. Details about banburismus, other Hut 8 cryptanalysis, and cribs are from Andrew Hodges, 197; Morris, 112–15; and interviews with Hinsley, Good, and Monroe. Direction-finding details are from Kemp interview. Information on Thring, Winn, and the Submarine Tracking Room is from MacLachlan, 102, 107–9; Beesly,
Very Special Intelligence
, 55–58, 158, 165–66, and passim.

168
Hut 4 handled non-Enigma: Hinsley interview.

169
“Gardening,” “special planting,” “Squares BF2927”: AIR 4/797:26A, 28A, and DEFE 3:27:ZTG/9880.

173
“who go out”: Winston S. Churchill,
The Unrelenting Struggle: War Speeches
(Boston: Little, Brown, 1942), 98.

Information on German weather ships is primarily from PG 36742 and, on their sailings, from PG 34814-34837. Details of the planning of the attack on the
München
are from Hinsley interview. Details of the attack are from ADM 199/447; ADM 53/114202; and interviews with Warmington, Low, Wiggeshof, and Rebelein. Bremerhaven, where the
München
was worked on, was then called Wesermünde.

176
“augmented weather report”: MA: M/19/36742:4.9.40.

176
U-Boat Command objected: Godt letter; Hessler, 145; Dönitz, 148.

176
October 24,
Adolf Vinnen:
PG 47109.

177
München: Lloyd’s Register of Shipping
, No. 11470.

177
Wetterkurzschlüssel:
M.Dv.Nr. 443.

182
three-page report: Hinsley, 1:565–69 (original is three pages long).

183
Holland: Ludovic Kennedy,
Pursuit: The Chase and Sinking of the Bismarck
(New York: Viking, 1974), 62; Ernie Bradford,
The Mighty Hood
(London: Hodder & Stoughton, 1959), 173.

185
“
Werde gejagt”:
PG 34833:7.5.41; DEFE 3:ZTP384.

187
“One of our patrols”:
Times
(May 10, 1941), p. 4, col. 6; PG 34832:10.5.41.

187
Hitler and Raeder discussed: Germany, Oberkommando der Kriegsmarine,
Lagevorträge
, 229, 231–38.

The references are the same as those for
Chapter 1
.

I am grateful to Captain Hugh Wilson and Chief Gunner’s Mate Thomas Kelly for reading a draft of this chapter and making extremely valuable comments and corrections.

Details of the capture of the
Lauenburg
, unless otherwise specified, are from ADM 199/430; ADM 53/14797; Kelly, diary; and interviews with Wilson, Kelly, Kennedy, Braun, and Klarman. Information on Gewald is from Buhr, Gratz interviews and Mohr, passim. On Bacon, from Forster, Hinsley interviews. On Skipwith, from Wilson, Kelly interviews.

199
cryptanalysts would face delays: Hinsley interview.

199
Lauenburg: Lloyd’s Register of Shipping
, No. 103 01.

205
“You don’t know”: Brice, 251.

212
Hinsley pleased: Hinsley interview.

Churchill’s passion for solved intercepts is detailed in “Churchill Pleads for the Intercepts,” ed. David Kahn,
Cryptologia
6 (January 1982), 47–49; Hinsley, 1:295; Gilbert,
Finest Hour
, 611–13, 814, 848–49. Aspects of his visit to Bletchley are from
Finest Hour
, 1185; Malcolm Kennedy, 439; Andrew Hodges, 205; Brown, 398; and interviews with Good, Milner-Barry, John and Mavis Batey, and Herivel.

The cryptanalysts’ problems, their letter, and Denniston’s removal come from Hinsley, 2:25–28, 655–57, 272–74, 279, 286, 289–90; Milner-Barry, “Action This Day,” 272–76; R. A. Denniston, 116–17, 122–24; Filby, 275–76; Malcolm Kennedy, 440; Brown, 401–2; Milner-Barry, Monroe interviews. Travis
is described in
Who Was Who, 1950–1959;
Malcolm Kennedy, 442; Welchman,
Hut Six Story
, 274; Brown, 397; Andrew Hodges, 177–78, 204; interviews with Milner-Barry, Twinn, and Davidson.

The story of convoy HX 155 was assembled from U.S. Navy, Navy Historical Branch, Operational Archives, Tenth Fleet Files, Convoy and Routing Section, Folder for HX 155; that archive’s World War II Action Report, Commander Destroyer Division 62 (Commander Task Unit 4.1.7), Escort of Convoys HX 155 and ON 31; RG 24, Logbooks of U.S. S.
Stur devant
and U.S. S.
Bainbridge;
BdU, KTB, 1.–30.Oktober 1941; SRMN-033, 4–30 October 1941; Hinsley, 2:174; Rohwer, “‘Special Intelligence,’” 719; Rohwer, “Ultra and the Battle of the Atlantic,” 422.

213
solution times: The solution time was calculated for each intercept in DEFE from May to August 1941 and averaged for each month.

213
reasons for July–August tonnage loss decline: Macintyre, 87, 88, 91.

214
eight bombes: Hinsley, 1:338; Welchman,
Hut Six Story
, 139.

214
Pound: Malcolm Kennedy, 439.

215
BONIFACE, ULTRA
: Gilbert,
Finest Hour
, 612.

216
TRITON
: Erskine, “Naval Enigma: Breaking of Heimisch and Triton,” 180. Some writers use
TRITON
to mean the four-rotor Enigma, but this is wrong.
TRITON
carried U-boat messages enciphered in three-rotor Enigma well before the four-rotor machine came into service on February 1, 1942 (see, for example, PG 32137:203 and M.Dv.Nr.443g, P. 4, of 1941).

220
Alexander takes over: Good, 5–6; Andrew Hodges, 204, 227–28.

220
McVittie: Filby and Howse interviews.

220
Kriegsmarine
weather cipher: BJ 5/288.

221
Archer: Howse and Wylie interviews.

222
Admiralty transmitted to Washington: copies in U.S. Navy’s Operational Archives.

Details of U-boat communications are from interviews with Meckel, Kuhne, and Wilde; NA:RG 165: Box 727, Folder U-118, Interrogation of Josef Hoeller, Oberfunkmaat, pp. 9, 10, 12, 17–19; SRGN 15993; SRMN-032, 98–99; Hirschfeld, 141–44; Dönitz (trans.), 231, 246.

The several investigations into German cipher security may be found in RM 7/103 at 38–39, 42, 62 (Stummel’s investigations), PG 34534 (Fricke’s first investigation), RM 7/121:57–61 (his second), and PG 32137 (Maertens’s investigation). Measures to restore or improve security are given in PG 34534 at 143–44, 153, and in MA:M797/47357:47.

The naval grid and its encipherment are described in Erskine, unpublished study; BdU, KTB, 1.–15.September 1941, Anlage; Hinsley, 2:681: ADM 223/3:259–60.

The proposals to improve the Enigma are in MA: III M 1006/6:51–55; RM 7/108:45. For the fourth rotor and the thin reflector, see Erskine and Weierud. On the B-Dienst and its successes: Tranow interview; MacLachlan, 77; Bonatz,
Deutsche Marine-Funkaufklärung
, 80, 86, 103, 105, 174; Bonatz,
Seekrieg
, 29, 32, 33, 36; Hinsley, 2:634–36; Kahn,
Hitler’s Spies
, 212–22; Dönitz letter, January 27, 1970.