![Sample our Humanities journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/5939/TOC-Subject-Sample-2021-Humanities.jpg"})
![Editing Services Awareness English-speaking]({"type":"image" , "src" : "/sda/110148/ED-Services-English.jpg"})
![Publish your Policy Brief rapidly today and inspire change for tomorrow.]({"type":"image" , "src" : "/sda/110967/JournalAd-CFP-SociologyF1000.jpg"})
This article explores the Eisenhower administration's efforts during 1960 to tackle the apparent nuclear-proliferation risk posed by innovations in gas-centrifuge technology. Washington developed a policy of denial, first tried out in 1954 when Brazil tried to purchase gas centrifuges in West Germany. In 1960, with advances in gas-centrifuge technology raising the possibility of secret uranium-enrichment plants, Atomic Energy Commission and State Department officials agreed that it should be classified secret to limit worldwide access. Yet West Germany, the Netherlands, and the United Kingdom were already undertaking gas-centrifuge research and development and German research was unclassified. While secrecy for any West German work on nuclear technology raised difficult political questions, without German co-operation security classification for gas-centrifuge technology in the United States and the other countries could fail. As a holding action to check nuclear proliferation, US diplomats reached agreement with the Germans, Dutch, and British on classification standards. Washington also sought export controls to limit access to the technology. Leaks to the press complicated diplomacy, but the four-power understanding on gas-centrifuge secrecy lasted for years, although A. Q. Khan significantly undermined it when he purloined Dutch centrifuge technology in 1975.
Notes
1. S. Maddock, Nuclear Apartheid: The Quest for American Atomic Supremacy from World War II to the Present (Chapel Hill, 2010), 130–1, 142; A. Cohen, Israel and the Bomb (New York, 1999), 79–97.
2. S.A. Levin, D. E. Hatch, and E. Von Halle, ‘Production of Enriched Uranium for Nuclear Weapons by Nations X, Y, and Z by Means of the Gas Centrifuge Process’, Operations Analysis Division, Union Carbide Nuclear Company, 26 Feb. 1960, M[andatory] D[eclassification] R[eview release by Department of Energy]. For ‘washing machine factory’, see US Congress, J[oint] C[ommittee on] A[tomic] E[nergy], Executive Session, 30 Aug. 1960, U[nited] S[tates] N[ational] A[rchives], [Record Group 128, Records of JCAE, Executive Session Transcripts, box 45, 30 Aug. 1960].
3. Maddock, Nuclear Apartheid, 90–1, 99–100, 111, 126–7; S. Schrafstetter and S. Twigge, Avoiding Armageddon: Europe, the United States, and the Struggle for Nuclear Nonproliferation, 1945–1970 (Westport, 2004), 72–3; G. Perkovich, India's Nuclear Bomb: Its Impact on Global Proliferation (Berkeley, 1999), 30–1; M. Trachtenberg, A Constructed Peace: The Making of the European Settlement 1945–1963 (Princeton, 1999), 240–1. Continually enriching the historiography is the work of the Nuclear Proliferation International History Project, http://www.wilsoncenter.org/program/NPIHP
4. For ‘gentleman's agreement’, see embassy Bonn cable 4560 to D[epartment] o[f] S[tate], 8 April 1969, USNA, [R]ecord [G]roup 59, [Records of the Department of State], Subject-Numeric Files 1967–1969, AE 11-1.
5. Maddock, Nuclear Apartheid, 99–100, 107; D. Fischer, History of International Atomic Energy Agency; The First Forty Years (Vienna, 1997), 9–57; Schrafstetter and Twigge, Avoiding Armageddon, 71–8.
6. For ‘built over time’, see A. Wellerstein, ‘Knowledge and the Bomb’ (Ph.D. dissertation, Harvard, 2010).
7. S. Whitley, ‘The Uranium Centrifuge’, Physical Technology, x (1979), 26–27; H.G. Wood, Alexander Glaser, and R. S. Kemp, ‘The Gas Centrifuge and Nuclear Weapons Proliferation’, Physics Today, September 2008, 40–1; R. Scott Kemp, ‘Gas Centrifuge Theory and Development: A Review of U.S. Programs’, Science and Global Security, xvii (2009), 2–3; and R. Scott Kemp, ‘The End of Manhattan: How the Gas Centrifuge Changed the Quest for Nuclear Weapons’, Technology and Culture, liii (2012), 272–305.
8. Ibid.; Wellerstein, ‘Knowledge and the Bomb’, at 167–92, 221–68, 325–52; W. Burr and T. Blanton, ‘The Costs and Consequences of Nuclear Secrecy’ in S.I. Schwartz (ed), Atomic Audit: The Costs and Consequences of U.S. Nuclear Weapons since 1940 (Washington, D.C., 1998), 433–83.
9. Kemp, ‘The End of Manhattan’, 288; N. Gall, ‘Atoms for Brazil, Dangers for All’, Foreign Policy, xxiii (Summer 1976), 181–2; J. Krasno, ‘Brazil's Secret Nuclear Program’, Orbis, xxxviii (1994), 429–30.
10. [U.S.] Hi[gh] Co[mmission] G[ermany] tel. 4023 to DoS, 23 June 1954, USNA, [RG 59], S[tate] D[epartment] D[decimal] F[iles], 762A.0221/6-2354; DOS, Documents on Germany, 1944–1985 (Washington, DC, 1985), 213.
11. W. Michael Weis, Cold Warriors and Coup d’Etats: Brazilian American Relations, 1945–1964 (Albuquerque, 1993), 76; R. Gordon Arneson to John A. Hall, AEC, 3 and 12 Feb. 1953, Robert P. Terrill to Gerard C. Smith, 7 June 1954, USNA, RG 59, [Records of] S[pecial] [Assistant to the Secretary of State for] A[tomic] E[nergy and Outer Space, Records Relating to Atomic Energy Matters, 1948–1962], box 477, Z1.10 Country File Brazil D. General 1953–54.
12. Robert Terrill to Gerard C. Smith, 11 June 1954, USNA, Record Group 84, Records of Foreign Service Posts, Top Secret General Records of U.S. Embassy Rio de Janeiro, 1944–1955, box 2, Top Secret 1954. For Groth, see Samuel A. Goudsmit, Alsos (Woodbury, NY, 1996), 94–5. For military objectives, see C. Patti, ‘The German Connection: The Origins of the Brazilian Nuclear Program and Secret West German-Brazilian Cooperation in the Early 1950s’, presentation at 2013 conference, Society for Historians of American Foreign Relations.
13. Hicog tel. 75 to DoS, 9 July 1954, SDDF, 762A.0221/7-954. For Conant, see J.G. Hershberg, James B. Conant: Harvard to Hiroshima and the Making of the Nuclear Age (New York, 1993).
14. DoS tel. 148 to Hicog, 16 July 1954, SDDF, 762A.0221/7-1649; Hicog tel. 1258 to DoS, 28 Oct. 1954, SDDF, 432.62AB/10-2854.
15. DoS instruction CA-2553 to Hicog, ‘Centrifuges for Brazil’, 16 Oct. 1954, SDDF, 862A.19/10-1654, and DoS tel. 1257 to Hicog, 4 Nov. 1954, RG 59. 432.62A8/10-2854.19/10-1654; embassy Rio de Janeiro tel. 333 to DoS, 30 Sep. 1954, SDDF, 762A.0221/9-3054. For the request for specifications, see DoS Instruction Airgram A-104, ‘Acquisition of Data on Gas Centrifuges’, 23 July 1954, SDDF, 762A.0221/7-954; Hicog Despatch 369 to DoS, ‘Acquisition of Data on Gas Centrifuges’, 7 Sep. 1954, SDDF, 762A.0221/9-754.
16. Hicog tel. 1258 to DoS, 28 Oct. 1954, SDDF, 432.62A8/10-2854; DoS tel. 1257 to Hicog, 4 Nov. 1954, SDDF, 462.62A8/10-2854; U.S. HiCog dispatch 1048, ‘Decisions Taken at the Meeting of the Commissioners of the Military Security Board on November 9, 1954’, 17 Nov. 1954, SDDF, 862A.19/11-1754.
17. H.-J. Grabbe, ‘Konrad Adenauer, John Foster Dulles, and West German-American Relations’ in R. Immerman (ed), John Foster Dulles and the Diplomacy of the Cold War (Princeton, 1990), 118–19; Trachtenberg, A Constructed Peace, 233–5; Union Carbide Corporation, Nuclear Division, ‘Nth Power Evaluation’, 4 March 1964; JCAE Executive Session, 30 Aug. 1960; Krasno, ‘Brazil's Secret Nuclear Program’, 429–30.
18. On Zippe and US intelligence, see Wood et al., ‘The Gas Centrifuge and Nuclear Weapons Proliferation’, 40, and R. Scott Kemp, ‘Gas Centrifuge Theory and Development: A Review of U.S. Programs’, Science and Global Security, xvii (2009), 2–3.
19. JCAE Executive Session, 30 Aug. 1960; [U.S].A[tomic] E[nergy] C[omission], AEC 610/15, ‘Gas Centrifuge Method of Isotope Separation’, 9 April 1960; AEC, ‘Gas Centrifuge’, enclosing ‘Report on Collaboration with Other Nations in Classification Policies Relative to Gas Centrifuges by Division of Classification, USAEC’, AEC 610/47, 14 Feb. 1964, MDR releases.
20. AEC 610/13, ‘Centrifuge Process for Uranium Enrichment’, 24 Feb. 1960, enclosing State Department memcon, 6 Feb. 1960, MDR release; AEC, ‘Gas Centrifuge Method of Isotope Separation’; AEC 610/15, 9 April 1960, MDR release; ‘Gas Centrifuge’, enclosing ‘Report on Collaboration with Other Nations in Classification Policies Relative to Gas Centrifuges by Division of Classification, USAEC’, 14 Feb. 1960, MDR release.
21. Wellerstein, ‘Knowledge and the Bomb’, at 167–92, 221–68, 325–52; Burr and Blanton, ‘The Costs and Consequences of Nuclear Secrecy’, 433–83.
22. AEC 610/13, ‘Centrifuge Process for Uranium Enrichment’, 24 Feb. 1960.
23. A.A. Wells, Director, Division of International Affairs, AEC, to Philip J. Farley, Special Assistant to the Secretary of State for Disarmament and Atomic Energy, ‘Control of and Cooperation in Gas Centrifuge Research and Development Program’, 19 Feb. 1960, Appendix D to AEC, ‘Gas Centrifuge Method of Isotope Separation’, AEC610/15, 9 April 1960, MDR release; P. Hayes, From Cooperation to Complicity: Degussa in the Third Reich (New York, 2005).
24. Levin, Hatch, and Von Halle, ‘Production of Enriched Uranium for Nuclear Weapons’, 26 February 1960; MDR release; Kemp, ‘The End of Manhattan’, 290.
25. For industrial secrecy in the Netherlands, see JCAE Executive Session, 30 Aug. 1960.
26. Levin, Hatch, and Von Halle, ‘Production of Enriched Uranium for Nuclear Weapons’, 26 Feb. 1960, MDR release.
27. For the ease of crossing technological barriers, see Kemp, ‘The End of Manhattan’, 274.
28. Meyers to Hartman, 21 March 1960, RG 59, USNA, [R]ecord [G]roup 59, [Records of the Department of State, Bureau of European Affairs, Office of Atlantic Political and Economic Affairs, Records Relating to] A[tomic] E[nergy [M[atters, 1960-63], box 2, Centrifuge; Philip J. Farley, Special Assistant to Secretary of State for Atomic Energy, to Algie Wells, Division of International Affairs, AEC, ‘Control and Cooperation in Centrifuge Research and Development’, 23 March 1960, SAE, box 298, [12.H Peaceful Uses Subject File.9 Gas Centrifuge 1960-62]; AEC, 'Gas Centrifuge Method of Isotope Separation’, AEC 610/15, 9 April 1960, MDR release.
29. Ibid.
30. C. Manthunga, ‘The Evolution of Irish Disarmament Initiatives at the United Nations, 1957–1961’, Irish Studies in International Affairs, vii (1996), 97–113; mem[orandum of] con[versation], ‘NSC Meeting on Nuclear Cut-Off’, 18 Feb. 1960, USNA, RG 59, Policy Planning Staff Records 1957–1961, box 116. Atomic Energy – Armaments 1960; N[ational] I[ntelligence][ E[stimate] 100-2-58, ‘Development of Nuclear Capabilities by Fourth Countries: Likelihood and Consequences’, 1 July 1958, and NIE 100-4-60, ‘Likelihood and Consequences of the Development of Nuclear Capabilities by Additional Countries’, 9 September 1960, CIA Freedom of Information Act releases; ‘Coolidge Report Recommendations on Arms Control Measures’, 14 Jan. 1960, USNA, RG 59, Office of Soviet Union Affairs Subject Files 1957–63, box 2, Coolidge Committee; Maddock, Nuclear Apartheid, x–xi, 51, 97, 109–10, 146; F.J. Gavin, ‘Politics, History and the Ivory Tower-Policy Gap in the Nuclear Proliferation Debate’, Journal of Strategic Studies, xxxv (2012), 587–92.
31. Maddock, Nuclear Apartheid, 126–7,138, 143; Trachtenberg, A Constructed Peace, 209–10, 240–1.
32. JCAE Executive Session, 30 Aug. 1960.
33. For ‘small centrifuges’, see Goodpaster, ‘Memorandum of conference with the President, March 11, 1960’, 14 March 1960, Dwight D. Eisenhower Library, Ann Whitman File, Dwight D. Eisenhower Diaries, box 48, Staff Notes March 1960.
34. Hartman to Meyers, 10 March 1960, RG 59, AEM, box 2, Centrifuge.
35. Meyers to Hartman, 21 March 1960, AEM, box 2, Centrifuge; Farley to Wells, ‘Control and Cooperation in Centrifuge Research and Development’, 23 March 1960, RG 59, SAE, box 298.
36. JCAE Executive Session, 30 Aug. 1960.
37. Position Paper, ‘Peaceful Uses of Atomic Energy’, 10 March 1960, USNA, RG 59, Executive Secretariat, Conference Files, box 214, CF 1611 Adenauer Visit March 1960; memcon, ‘NSC Meeting on Nuclear Cut-Off’, 18 Feb. 1960; memcon, ‘Manufacture and Export of Ultra-Centrifuge Equipment’, 15 March 1960, SDDF, 862A.394/3-1550.
38. Memcon, ‘German Development of Ultra-Centrifuge’, 12 May 1960, RG 59, SDDF, 862A.394/5-1260.
39. Charles A. Sullivan to Ambassador Walter G. Dowling, 28 April 1960, SAE, box 298, 12.H Peaceful Uses Subject File.9 Gas Centrifuge 1960–62; memcon, ‘German Development of Ultra-centrifuge’, 12 May 1960, SDDF, 862A.394/5-1260; embassy Bonn tel. 2312 to DoS, 7 June 1960, SDDF, 611.62A45/6-660; Farley to the Secretary, ‘Controls on Ultracentrifuge Development’, 8 June 1960, SAE, box 298.
40. Embassy Bonn tels 2312 and 2473 to DoS, 7 and 30 June 1960, SDDF, 611.62A45/6-760 and 6-3060.
41. ‘Telephone calls, Tuesday, 7 June 1960’, Minutes of Telephone Conversations of John Foster Dulles and Christian A. Herter, 1953–1961 (Washington, D.C., University Microfilms, 1980), microfilm reel 11; memcon, ‘German Ultra-Centrifuge Development’, 8 June 1960, SDDF, 862A.394/6-860.
42. Ibid; G. Skogmar, The United States and the Nuclear Dimension of European Integration, (New York, 2004), 225.
43. Martin J. Hillenbrand to Mr. Kohler, ‘State-AEC Ultra-centrifuge Discussions in Bonn July 13’, 6 July 1960, RG 59, AEM, box 2, Centrifuge.
44. Farley to the Acting Secretary, ‘Gas Centrifuge Discussions with GFR’, 8 July 1960, SAE, box 298, 12.H Peaceful Uses Subject File.9 Gas Centrifuge 1960–62.
45. Untitled document, n.d., SAE, box 298, 12.H Peaceful Uses Subject File.9 Gas Centrifuge 1960-62; DoS cable 10 to Embassy Bonn, 8 July 1960, 611.62A45/7-760; Hugh S. Cumming, jr. to Foy D. Kohler, ‘Growing Revelation of West German Interest in Nuclear Striking Force in Europe’, 18 Feb. 1960, RG 59, SDDF, 740.5/2-1860; Skogmar, The United States and the Nuclear Dimension of European Integration; W. Hanreider, Germany, America, Europe: Forty Years of German Foreign Policy (New Haven, 1989).
46. For the meetings, see ‘Report of U.S. Team Concerning the Gas Centrifuge Process in Germany, the Netherlands, and the United Kingdom July 13–20, 1960’, AEC 610/24, 4 August 1960, DOE MDR release. See also Embassy Bonn cables 91 and 102 to DoS, 14 July 1960, SDDF, 611.62A45/7-1459, US Embassy The Hague cable 72 to DoS, 16 July 1960, SSDF, 611.62A45/7-1690; and Philip J. Farley to Under Secretary, ‘Briefing Papers on Gas Centrifuge, Communications Satellites, and Safeguards for Indian Power Station’, 22 July 1960, enclosing ‘State/AEC Discussions with Germans, Dutch, and British of Gas Centrifuge Control Measures’, RG 59, SAE, box 298.
47. Embassy Bonn cables 91 and 102 to DoS, 14 July 1960, SSDF, 611.62A45/7-1459; Philip J. Farley to Under Secretary, ‘Briefing Papers on Gas Centrifuge, Communications Satellites, and Safeguards for Indian Power Station’, 22 July 1960, enclosing ‘State/AEC Discussions with Germans, Dutch, and British of Gas Centrifuge Control Measures’, RG 59, SAE, box 298; Embassy The Hague cable 72 to DoS, 16 July 1960, SSDF, 611.62A45/7-1690.
48. R.J. Graneiri, The Ambivalent Alliance: Konrad Adenauer, the CDU/CSU, and the West, 1949–1966 (New York, 2003), 110–21.
49. Embassy The Hague cables 70 and 78 to DoS, 16 and 19 July 1960, SSDF, 611.62A45/7-1690. Forthcoming work by E.A.A. Hellendorn, Utrecht University, will shed light on the Dutch gas-centrifuge program and Western European policies and perspectives generally.
50. Ibid. (cable 78).
51. Farley to Under Secretary, ‘Briefing Papers on Gas Centrifuge, Communications Satellites, and Safeguards for Indian Power Station’, 22 July 1960, RG 59, SAE, box 298; ‘Report of U.S. Team Concerning the Gas Centrifuge Process’, 4 Aug. 1960, MDR release.
52. D. MacKenzie and G. Spinardi, ‘Tacit Knowledge, Weapons Design, and the Uninvention of Nuclear Weapons’, The American Journal of Sociology, ci (1995), 44–99.
53. ‘Report of U.S. Team Concerning the Gas Centrifuge Process’, 4 Aug. 1960, MDR release; DoS instruction CA-894, ‘Gas Centrifuge Classification Guide’, 27 July 1960, SSDF, 103-AEC/7-2760, and DoS instruction CA-3461, ‘Centrifuge Classification Guide – Revision’, 19 Oct. 1960, 1 SSDF, 103.AEC/10-1960.
54. JCAE Executive Session, 30 Aug. 1960.
55. DoS circular 179 to embassy Bonn et al., 29 July 1960, SSDF, 862a.1901/7-2960; DoS cable 283 to embassy Bonn et al., 9 Aug. 1960, RG 59, AEM, box 2, Centrifuge.
56. Ibid; embassy Bonn cable 294 to Department of State, 19 Aug. 1960, SSDF, 862A.1901/8-1960; DoS cable 366 to embassy Bonn, 25 Aug. 1960, SSDF, 862A.19018-1960; embassy Bonn cable 292 to DoS, 18 Aug. 1960, AEM, box 2, Centrifuge; DoS cable 355 to embassy Bonn, 24 Aug. 1960,SSDF, 862A.1901/8-2460; DoS cable 1293 to embassy London, 25 Aug. 1960, SSDF, 862A.1901/8-1858; embassy London cable 1005, 26 Aug. 1960 and DoS cable 399 to embassy Bonn, 31 Aug. 1960, SSDF, 862A.1901/8-2660; C. Browning, ‘The Foreign Office Revisited’, Bulletin of the German Historical Institute, Autumn (2011), 75.
57. JCAE Executive Session, 30 Aug. 1960.
58. Embassy Bonn cable 328 to DoS, 29 Aug. 1960, SSDF, 862A.1901/8-2960; embassy The Hague cable 349 to DoS, 14 Sep. 1960, SSDF, 862A.1901/9-1460; memcon, ‘Meeting with Professor Groth of the University of Bonn on Gas Centrifuge System’, 21 Sep. 1960, and ‘German Classification of Centrifuge Work’, 4 Oct. 1960, SAE, box 298.
59. US Embassy Bonn cable 556 to DoS, 13 Oct. 1960, SSDF, 611.62A45/10-1360. The internal accommodation to secrecy involved conflict; Groth and other researchers would eventually sue the FRG for damages. See Kratzer to AEC, ‘Gas Centrifuge Developments in Germany’, 6 May 1965, MDR release.
60. Operations Coordinating Board, ‘Meeting of November 2, 1960’, 7 Nov. 1960, Dwight D. Eisenhower Library.
61. ‘Cheaper A-Bomb Process is Threat to Arms Control’, New York Times, 11 Oct. 1960; ‘Curbs Assured on Uranium’, Washington Post, 12 Oct. 1960.
62. DoS cable 674 to embassy Bonn, 11 Oct. 1960, SSDF, 611.62A45/10-1160.
63. Memo for the Files, ‘Press conference in Bonn on Ultra-centrifuge Process’, 13 October 1960, SAE, box 298; Embassy Bonn cable 338 to DoS, 13 Oct. 1960, SSDF, 611.62A45/10-1360; embassy London cable 1768 to DoS, 13 Oct. 1960, SSDF, 611.62A45/10-1260.
64. DoS cable 702 to embassy Bonn, 14 Oct. 1960, SDDF, 611.62A45/10-1360. For Soviet concerns see embassy Paris cable 84 to DoS, 7 July 1960, SSDF, 862A.1901/7-760.
65. Edward L. Brady to John A. Hall, 10 Nov. 1960, RG 59, SAE, box 298.
66. Embassy The Hague cables 1267 and 37 to DoS, 5 April 1961 and 12 July 1961 respectively, SSDF, 103-AEC/4-561 and 7-2760.
67. AEC Press Release, ‘AEC Proposes to Extend Access Permit Program to Permit Development by Private Industry of Gas Centrifuge’, 13 Dec. 1960. SAE, box 298.
68. ‘Statement by John A. McCone, Chairman [AEC], on Status and Prospects of Gas Centrifuge Technology’, 13 Dec. 1960, SAE, box 298; ‘AEC Gives Report on Gas Centrifuge’, New York Times, 14 Dec. 1960; ‘Tighter Secrecy for Uranium Process’, The New York Times, 28 June 1964.
69. ‘Nth Power Evaluation’, 4 March 1964, MDR release.
70. William C. Harrop to Stanley Cleveland, ‘EURATOM’, 23 April 1962, SDDF, 840.1901/4-2363; S. Schrafstetter and S. Twigge, ‘Spinning into Europe: Britain, West Germany and the Netherlands - Uranium Enrichment and the Development of the Gas Centrifuge 1964–1970’, Contemporary European History, xi (2002), 255–60; D. Albright and C. Hinderstein, ‘Unraveling the A.Q. Khan and Future Proliferation Networks’, The Washington Quarterly, xxviii (2005), 111–28; D. Albright, A. Stricker, and H. Wood, Future World of Illicit Nuclear Trade: Mitigating the Risk (Washington, DC, 2013)
71. AEC, ‘A Study of Gas Centrifuge As it Relates to the Proliferation of Nuclear Weapons’, n.d. [circa January 1967], MDR release.
72. For COCOM's formation, see F. Cain, Economic Statecraft During the Cold War: European Responses to the U.S. Trade Embargo (London, 2007), 20–6.
73. U.S. International Cooperation Administration, The Strategic Trade Control System (Washington, DC, 1957), 28–9; JCAE Executive Session, 30 Aug. 1960; Department of State instruction CA-9020 to U.S. embassy Bonn et al, ‘AE Discussions’, 29 April 1960 and Department of State instruction CA-7766 to U.S. Mission for Regional Organizations, ‘Atomic Energy List Review’, 15 March 1961, both in SDDF, 460.509/4-2960 and 3-1561 respectively.
74. U.S. Mission to Regional Organizations airgram A-386, ‘Atomic Energy List Review’, 15 May 1961, SDDF, 460.509/5-1561.
75. W.B. McCool to AEC, ‘Classification of Gas Centrifuge Information’, 15 March 1964, AEC 610/48, MDR release.