While she stood quietly, they erupted in cheers: Ibid.
“I was just doing what Mr. Rowlett told me to do”: Grotjan interview with Kahn.
“When Gene… brought in those worksheets and pointed out”: Frank Rowlett, oral history, NSA-OH-01-74 to NSA-OH-12-74, 284.
Three years later, Friedman wrote a top secret: William Friedman, “Recommendations for Legion of Merit and Medal of Merit Awards,” September 27, 1943, https://www.nsa.gov/news-features/declassified-documents/friedman-documents/assets/files/correspondence/FOLDER_529/41771309081039.pdf.
His private announcement was made on September 27, 1940: “History of the Signal Security Agency,” vol. 2, 44.
“What was really mysterious was the fact”: RG 0457, 9002 (A1), Box 81, SRH 280, “An Exhibit of the Important Types of Intelligence Recovered Through Reading Japanese Cryptograms.”
“England and America are jingling money”: RG 0457, 9032 (A1), Box 833, “Diplomatic Translations of White House Interest, 1942–1943.”
Each day, messages like these were deciphered: RG 0457, 9002 (A1), Box 78, SRH 269, Robert L. Benson, “US Army Comint Policy: Pearl Harbor to Summer 1942,” notes that at first raw message transcripts were delivered, but intelligence officials later drew up summaries. Kahn, “Why Weren’t We Warned?” says that fifty to seventy-five intercepts were solved and translated each day; the most important were sent on, carried in locked briefcases. The messenger then retrieved the papers and burned them.
“Through their almost na?ve confidence”: RG 0457, 9032 (A1), Box 1115, “History of the Language Branch, Army Security Agency.”
So eager were the two services for credit: The odd-even compromise is discussed in a number of places, including Budiansky, Battle of Wits, 168. That Frank Raven, with the U.S. Navy, found a way to predict the keys is in John Prados, Combined Fleet Decoded (New York: Random House, 1995), 165.
The Purple machine could not predict the attack: A good description of what could and could not be read on December 7, 1941, is in Robert J. Hanyok, “How the Japanese Did It,” Naval History (December 2009): 48–49. Kahn points out that the Imperial Japanese Navy did not clue in the Japanese diplomats in “Why Weren’t We Warned?” 59.
Driving back from a tour of the proposed installation: These descriptions of Arlington Hall are taken from a sheaf of internal histories and briefing papers provided to the author by Michael Bigelow, historian at the U.S. Army Intelligence and Security Command.
Delia Taylor and Wilma Berryman had rented rooms one summer: Wilma Berryman Davis, oral history interview, December 3, 1982, NSA-OH-25-82, 10.
“The finishing school atmosphere was shattered”: RG 0457, 9032 (A1), Box 1125, “Signal Security Agency, History of the Cryptographic Branch.”
The Purple machine was installed: Budiansky, Battle of Wits, 226.
There was a French code they called Jellyfish: RG 0457, 9032 (A1), Box 1114, “Signal Security Agency Weekly Reports, Jan to Oct 1943,” Weekly Report for Section B-III, July 9, 1943.
“The outstanding solution of the week was that of the SAUDI cipher”: RG 0457, 9032 (A1), Box 1114, “Signal Security Agency, B-III Weekly Reports Oct–Dec 1943,” Weekly Report for October 9, 1943.
Sometimes, when she was riding the bus: Grotjan interview with Kahn.
Chapter Four: “So Many Girls in One Place”
She had grown up in the crossroads of Bourbon, Mississippi: Kitty Weston, interview at her niece’s home in Oakton, Virginia, on April 10, 2015, and Clyde Weston, telephone interview on October 9, 2015. Also Personnel Record Folder for War Department Civilian Employee (201) file: “Weston, Carolyn Cable,” National Personnel Records Center, National Archives, St. Louis, MO.
The goal of the lecture series, This Is Our War: RG 0457, 9002 (A1), Box 17, SRH 057, Lecture Series This Is Our War, Autumn 1943.
Early in December 1943: Curtis Paris to Dot Braden, December 4, 1943.
Chapter Five: “It Was Heart-Rending”
The two diplomats were hatching plans to sow discord: RG 0457, 9032 (A1), Box 606, “Items of Propaganda Value.”
Japan had a brilliant top commander: RG 0457, 9002 (A1), Box 71, SRH 230, Henry F. Schorreck, “The Role of COMINT in the Battle of Midway,” Cryptologic Spectrum (Summer 1975): 3–11.
The U.S. Navy had a small cryptanalytic team: Captain Rudolph T. Fabian, oral history interview on May 4, 1983, NSA-OH-09-83, 8–30.
In the Atlantic, things were going equally badly: RG 0457, 9002 (A1), Box 95, SRH 367, “A Preliminary Analysis of the Role of Decryption Intelligence in the Operational Phase of the Battle of the Atlantic.”
The Battle of the Atlantic began: David Kahn, Seizing the Enigma (New York: Barnes and Noble, 2001), vii.
To be sure, the Allies for some of this time: “The British were using an enciphered code for the convoy thing and we were convinced that the Germans were reading it. And we told them that and it was hard to persuade them that it was true.… I think we did some monitoring to see if we could prove our point, which we couldn’t.” Dr. Howard Campaigne, oral history interview on June 29, 1983, NSA-OH-14-83, 49.
Even if it was theoretically possible: Lieutenant Howard Campaigne said that a fact-finding team went to Germany after the war and “we found that the Germans were well aware of the way the Enigma could be broken, but they had concluded that it would take a whole building full of equipment to do it. And that’s what we had. A building full of equipment. Which they hadn’t pictured as really feasible.” Campaigne, oral history, 15–16.
The Poles broke the Enigma: Chris Christensen, “Review of IEEE Milestone Award to the Polish Cipher Bureau for the ‘First Breaking of Enigma Code,’” Cryptologia 39, no. 2 (2015): 178–193, DOI: 10.1080/01611194.2015.1009751; Ann Caracristi, interview, undated, Library of Congress Veterans History Project, https://memory.loc.gov/diglib/vhp-stories/loc.natlib.afc2001001.30844/transcript?ID=mv0001, comments by National Cryptologic Museum curator Jack Ingram.
In January 1941, naval code breaking consisted: RG 38, Box 110, “Historical Review of OP-20-G.”
According to a November 1941 proposed salary memo: RG 38, Box 1, “CNSG Officer/Civilian Personnel Procurement 1929–1941 (1 of 2).”
The early women came from a variety: Francis Raven, oral history interview on March 28, 1972, NSA-OH-03-72, 3, provided the Puffed Rice anecdote.
“Could you start within a week or two after”: Personnel Record Folder for War Department Civilian Employee (201) file: “Beatrice A. Norton,” National Personnel Records Center, National Archives, St. Louis, MO.
By now the women’s ranks had winnowed: RG 38, Box 113, “CNSG-A History of OP-20-3-GR, 7 Dec 1941–2 Sep 1945.”