Sharing the Burden:

Women in Cryptology 

during World War II
Cover Photos: COLOSSUS

This publication is a product of the National Security Agency 

history program. It presents a historical perspective for informational and educational purposes, is the result of independent 

research, and does not necessarily reflect a position of NSA/CSS 

or any other U.S. government entity.

This publication is distributed FREE by the National Security 

Agency. If you would like additional copies, please submit your 

request to: 

Center for Cryptologic History

National Security Agency

9800 Savage Road, Suite 6886

Fort George G. Meade, MD 20755-6886

Cover Photo: Women cryptologists at work at Arlington Hall. At 

the right front is Ann Caracristi, who would later become deputy 

director of NSA.
Sharing the Burden:

Women in Cryptology 

during World War II

Jennifer Wilcox

Center for Cryptologic History

National Security Agency

Printed 1998

Reprinted 2013

1

The cryptanalysts working for the Signals Intelligence Service1 (SIS) of the U.S. Army knew how crucial it was 

to decipher and read Japanese secret messages. But this new 

code, “Purple,” wasn't breaking.

For eighteen months the team struggled with this difficult 

Japanese diplomatic code. Then, one day in September 1940, 

Genevieve Grotjan made a discovery that would change the 

course of history. By analyzing and studying the intercepted 

coded messages, she found a correlation that no one else had 

yet detected. This breakthrough enabled other cryptanalysts to 

find similar links.2 Shortly thereafter, SIS, along with the U.S. 

Navy, built a “Purple” analog machine to decode the Japanese 

diplomatic messages.

Almost sixty years later, Frank Rowlett, a cryptologic pioneer and head of the “Purple” team, remembered that historic 

day: “What [Genevieve] Grotjan did was a big step forward and 

was very significant in the solution of the ‘Purple’.”3 Her discovery, and the work of other team members, allowed the United 

States to read secret Japanese diplomatic messages and to continue reading them throughout World War II.

Genevieve Grotjan’s contribution to the Allied victory cannot be measured. Nor can the contributions of the thousands 

of women serving their country through cryptography. Like 

Setting the Stage
2

Genevieve, many women working in cryptology during World 

War II were civilians; thousands of others were in the military.

Volunteering for Duty

President Franklin Roosevelt signed the bill establishing the Women’s Army Auxiliary Corps (WAAC) on May 15, 

1942.4 A few months later, on July 30, he signed a similar bill 

for the Navy which created the Women Accepted for Voluntary 

Emergency Service, more commonly known as the WAVES.

Women across the country volunteered for military duty. 

The New York Times stated that 10,000 women reported to 

Army recruiting stations the first day the WAAC accepted applications for officer training.5 The applications had to be returned 

in only one week; even so, the Army received over 35,000 

applications. They had fewer than 1,000 officer positions available.6Likewise, the Navy began receiving hundreds of requests 

each day for applications, even before the forms were available. They received nearly 25,000 requests for only 900 officer 

commissions.7

Women who joined the military relieved men by working in 

noncombatant positions. These men were desparately needed 

to fight the battles overseas. One observer described the situation this way:

As the war got under way the drain upon manpower brought 

the Signal Intelligence Service into keen competition for personnel with industry and other government agencies. Not only 

was it difficult to obtain deferment for male civilian employees, but it was almost impossible to keep many of the younger 

officers qualified for overseas assignments, but badly needed 

at Headquarters, from being put on orders for shipment to 

theaters of operations. In view of this ‘uncopasetic’ situation the Signal Intelligence Service turned its attention to the 

procurement of (1) military personnel, particularly Wacs, (2) 

female civilians, and (3) males who had been given deferred 

status by Selective Service.8 
3

Cryptography was one of the most vital of these “sit-down” 

jobs. The Army and Navy had sizeable cryptographic offices; 

however, even they were small compared to their eventual size 

at the height of the war. The Army’s Signal Intelligence Service 

had 331 people, military and civilian, when Pearl Harbor was 

attacked on December 7, 1941. The Navy’s communications 

security section (OP-20-G) had 730 people, Navy personnel 

and civilians who worked in radio intelligence, cryptography, 

and security. Their work involved cryptanalysis, cryptographic 

development and security, and laboratory work for photographic services and special inks. The SIS worked closely with the Second Signal Service Battalion, which provided radio intelligence.9

Only those women meeting higher qualifications were 

admitted into cryptologic work. Women in the Army had to 

meet officer qualifications, as well as have strong mathematics or language skills. The Navy competed with the Army for 

women with similar qualifications and offered officer status for 

cryptographers.10

However, both services placed a higher value on a woman’s 

integrity than on her skills. A woman with the right qualifications, but not trained in cryptography, could learn the skills. But 

a woman whose loyalty was in question, no matter how qualified, could not be selected for this highly classified work. In a 

memo from the Navy’s cryptologic office, OP-20-G, Captain 

Laurance Safford responded to a query concerning the recruitment of women: 

In view of the confidential nature of the work done in 

this section, it is essential that all personnel be especially selected for integrity. Individual qualifications are of 

secondary concern, and used only as a basis for assignments after integrity has been established.11

Anyone working in the field had a thorough background 

investigation. This delayed the acceptance of personnel into 

cryptography, but could not be avoided. The security of the 

work required trustworthy people.
4

Since most of the operating personnel of the Signal [Intelligence Service] were entrusted with SECRET and TOP SECRET 

cryptographic and cryptanalytic matters affecting the security 

of the nation as a whole, the Agency in all its recruiting of personnel sought individuals: 

1. of excellent character who were citizens, preferably native 

born, of the United States;

2. who had no intimate connection with foreigners in the 

United States or foreign countries; 

3. whose loyalty, integrity, discretion, and trustworthiness 

were unquestioned; and

4. whose financial status and/or habits were such as to render unlikely their succumbing to any temptation that might 

endanger national security.12

Due to the secret nature of the work, recruitment was difficult. The Signal Intelligence Service conducted several recruitment drives for both civilians and Wacs. However, the type of 

positions for which they needed people could not be adequately 

advertised. An article in the New York Times described assignments as “highly confidential work of great tactical importance, 

closely connected with the safety of our forces on the fighting 

front.”13

The Navy had its own recruiting concerns. Many women 

performing cryptologic duties were already working for the 

Navy as civilians. For these women, and the Navy, there were 

benefits to their remaining civilians. From the women’s point of 

view, they worked during the day, received vacations, and could 

quit if they chose. OP-20-G civilians could not be absent from 

their work attending the Navy’s indoctrination school. However, there were also benefits for the Navy if the women joined 

the service. As WAVES, they would do communications work 

for the duration of the war, and they could be assigned to the 

less desirable shifts, such as nights and weekends. So it was a 

mixed message the female civilians received from Commander 
5

John Redman, head of OP-20-G, when Congress considered a 

Women’s Naval Reserve:

We encourage and advise our women employees to apply for 

the Corps but we assure them that the existing SP and P Civil 

Service program is expected to continue indefinitely.

... Yet they must expect a rather long transition period extending well into 1943. It would be an unbearable hardship on the 

Section to attempt an immediate universal change; the work 

the women are now doing is too important to the war effort to 

risk a period of absence and disorganization.

14

Indoctrination and Training

Fifty-nine women from OP-20-G were approved as officer candidates. OP-20-G submitted their names along 

with a request that their indoctrinations be staggered in order 

to avoid the loss of their services at one time. However, they 

were informed that the first six women would report for indoctrination school on October 6, 1942, and that the remaining 

candidates would report during November. This meant that a 

majority of the women would be gone from the section for at 

least a month and that the efficiency and production of the 

office would be seriously affected. OP-20-G again requested the 

WAVES’ indoctrinations be staggered by sending three smaller 

groups every six weeks. They explained that delaying each goup 

would ensure “that no serious disruption of very important work 

of a secret nature would occur as a result of the simultaneous 

detachment of 35 young women.”15 Although the groups were 

not separated by the desired six weeks, they were staggered by 

several weeks, alleviating some of OP-20-G’s concerns.

The Army handpicked the men and women enrolled in their 

cryptographic course. Initially, the training was provided at Fort 

Monmouth, New Jersey, but was later transferred to Vint Hill 

Farms Station in Virginia. Those students who demonstrated 

the necessary skills within the first six weeks of cryptanalysis 

training continued on. They learned “cryptographic security, 
6

Army and staff organization from a signal intelligence viewpoint, elementary and advanced cryptography, IBM theory and 

operation, code compilation, and the preparation of cryptanalytic work sheets. The more advanced course also covered ... language instruction in Japanese, German, Italian, French, Spanish, and Portuguese,...and military cryptanalysis.”16

The Navy provided cryptology classes in several colleges 

prior to the war in order to create a pool of trained personnel. 

Baltimore’s Goucher College trained a small group of Navy students. English professor Ola Winslow taught the secret cryptology classes in a locked room on the top floor of Goucher Hall. 

After graduating, most chose to join the WAVES and went to 

Smith College or Mount Holyoke for additional Navy indoctrination. At least one graduate joined the WAC, and some chose 

to continue in cryptology, in a civilian status.17 Other WAVES 

received their code training in a three-month course at Smith 

College. However, hundreds of positions in OP-20-G did not 

require cryptanalysis training. WAVES whose loyalty and test 

scores indicated an ability for these jobs went straight from 

Hunter College boot camp to work in Washington, D.C. 

A classroom inside Arlington Hall Station
7

Getting Down to Work

The Army and Navy assigned the cryptographic graduates to their respective cryptanalysis offices. The Army 

made its SIS headquarters the Munitions Building in Washington, D.C. (Genevieve Grotjan made her break into the “Purple” 

code while stationed there.) But the growing demand for signals intelligence throughout the war required more personnel 

and more space. In 1942 the SIS moved to a junior college for 

girls in Arlington, Virginia. It became known as Arlington Hall 

and was the largest message center in the world. The Navy also 

needed larger spaces as it grew throughout the war. In February 

1943 it relocated its cryptographic offices from the Navy Department building in Washington, D.C., to Mount Vernon Seminary 

just five miles away. This facility had also been a girls’ school. It 

became known as the Naval Communications Annex.

Here men and women, civilian and military, worked to 

break the coded messages. Many had a background in mathematics. College graduates recruited locally and around the 

country applied their mathematical skills to the science of cryptology. The Navy’s Enigma Office (OP-20-G) was known as the 

“Office of College Professors” because many of the officers were 

Ph.D.s and teachers.18

B branch inside Arlington 

Hall Station
8

One of the best cryptanalysts of the time, Agnes Meyer 

Driscoll, worked for the Navy as a civilian. Known to some as 

“Miss Aggie,” she too was a math teacher before joining the Navy 

in 1918. The Navy introduced her to her life’s work in cryptology. Following World War I, except for a few years in the 1920s 

when she worked for another cryptographic pioneer, Edward 

Hebern, Agnes continued in cryptology with the Navy and other 

organizations (including NSA) for the rest of her career. She is 

credited with making breaks into most of the Japanese naval 

codes OP-20-G worked on.

In the navy she was without peer as a cryptanalyst. Some of 

her pupils, like Ham Wright, were more able mathematicians 

but she had taught cryptanalysis to all of them, and none ever 

questioned her superb talent and determination in breaking 

codes and ciphers... Among her uniformed naval colleagues, 

she was held in the highest esteem throughout her long career, 

which continued from the Office of Naval Communications to 

the Armed Forces Security Agency, and then to the National 

Security Agency, before she retired in 1959.19

Women accepted into the cryptologic field were sworn to 

secrecy. The penalty for discussing the work outside of approved 

channels could be death, as it was considered an act of treason 

during a time of war. One Wac still recalled more than fifty 

years later, the first lecture she received: “Don’t talk.” The Army 

informed her and her fellow Wacs that no one was to know of 

their work. Anyone caught discussing it would be treated as a 

spy and shot.20 The Navy gave their WAVES the same warning. 

Elizabeth Allen Butler, stationed at the Naval Communications 

Annex, wrote home in 1943, “As far as my telling you about my 

work. I can’t. It’s very secret, one of the most in the Navy. You 

have a terrible time getting into the place even with a uniform 

on and then you have to wear two badges and show them to the 

Marines who are on guard at the front of the building.”21Constance McCready Rush described it this way: “Everything going 

on in our airless attic was so secret–more so than in some other
9

 areas of the building except the actual codebreaking room–that 

only four or five high-ranking officers were allowed to enter.”22

To help maintain the secrecy, neither the Army nor the Navy 

told the women how their work fit into the whole. WAVE Georgia Ludington explained, “We weren’t supposed to know anything. We just did something and it didn’t all fit in. We didn’t 

know the big picture.”23The actual cryptanalysts knew how their 

achievements aided the men overseas, but the Wacs in the Second Signal Service Battalion intercepting coded messages and 

the WAVES operating the cryptanalytic machines rarely learned 

the results of their efforts.

Women assigned to the Second Signal Service Battalion 

received training on radio intercepting and morse code transcribing of katakana, a syllabic form of Japanese writing. The 

training emphasized that they couldn’t make mistakes. If they 

didn’t understand or hear a portion of the code, they were not to 

guess. It was better to have a blank, indicated by three dots (...), 

than to have an incorrect letter. A wrong guess could affect the 

cryptanalyst’s ability to break the message. The Wacs’ transcriptions were forwarded to Arlington Hall for analysis, decryption, and translation. But the intercept operator never knew 

the details of the messages she copied, nor if she had somehow 

helped a mission or a soldier.

The BOMBE

The Navy also told their WAVES as little as possible in order to maintain secrecy. They sent some 600 newly 

inducted WAVES, along with 200 men, to Dayton, Ohio, to help 

build and train on the cryptanalytic Bombes. These machines 

were to be used to help break German messages enciphered on 

an Enigma machine. Each Bombe required sixty-four rotors to 

be wired to match the rotors actually used in the Germans’ Enigma. WAVES performed this task. Each woman was given a wiring diagram for one side of the two-sided rotor. She spent her 

eight-hour shift soldering wires to rotors. Another WAVE sol-
10

dered the other side. This arrangement maintained the secrecy 

of the rotor wirings. No WAVE would have knowledge of both 

sides of any rotor.

 Eventually, the Navy built 120 Bombes and sent them to 

the Naval Communications Annex. Here, women began operating the machines. Three shifts of women ran them twentyfour hours a day. The work was noisy and hot, but the Navy had 

impressed upon them the importance of their work, without ever 

explaining how their work fit into the whole cryptanalytic effort. 

Commander Gilman McDonnell, a supervisor on the Bombe 

deck, recalled an incident in which a rotor solution, known as a 

jackpot, was accidentally thrown out. The resulting delay made 

it apparent to the chief of the Bombe operations, John Howard, 

that some kind of explanation was necessary.

Eventually we got the answer and then they realized that the 

wheel order had already been run and should’ve been a jackThe N-530 Bombe, located on the second deck 

of building 4 (Photo dated 15 May 1945)
11

pot. Well, it had obviously been thrown in the burn bag by 

mistake. So John got permission from his superiors to tell the 

girls something to give them some sense of how important the 

work was.

We shut down operations for about ten minutes and he got 

up on a chair in the middle of the operations area. He didn’t 

tell them specifically what they were doing, but said they were 

attacking an enemy cipher and it was a very important job.... 

And that’s all they knew.24

The Second Signal Service Battalion

Unlike many occupations women entered during the war, cryptology was never a traditionally male job. 

Since the beginning of permanent cipher bureaus following 

World War I, women civilians had worked in the Army and 

Navy code rooms. There were other positions in the intelligence 

field, however, that had always been filled by men, such as the 

radio intercept operators. Women proved repeatedly that they 

could do the work as capably as, and sometimes better than, the 

men they replaced. A WAC staff director, reporting on the Wacs 

in the Second Signal Service Battalion, said, “It was proven over 

and over again that women were far better equipped than men 

for routine but detailed work.”25

Women in the Army’s Second Signal Service Battalion 

worked as high-speed radio operators, teletype operators, 

switchboard operators, cryptographic code clerks, cryptanalysts, and route clerks. They intercepted and forwarded coded 

enemy messages to SIS headquarters where other Wacs, soldiers, and civilians worked to break them. Arlington Hall analyzed, decoded, translated, interpreted, and distributed these 

messages. They were also responsible for the security of American communications and had a branch devoted entirely to that 

endeavor. The Second Signal Service Battalion monitored the 

U.S. Army radio transmissions looking for poor communica-
12

tions practices which would make it easier for the enemy to 

decrypt U.S. messages.

Travel and Working Conditions

T he Signal Corps sent Wacs to various countries in Europe and North Africa: England, Italy, France, Algeria, and 

others. Female Signal Corps personnel in Europe reached over 

1,700. This number accounted for nearly one quarter of the 

Wacs stationed in that theater, though not all were involved in 

cryptographic work.26 Considerably fewer women specializing 

in communications were assigned to the Pacific Theater. However, Signal Intelligence Service assigned Wacs to New Guinea, 

Australia, the Phillipines, and other locations as the Americans gained control of the South Pacific.27 The Boyce Report 

described these 120 Wacs with the SIS in the Southwest Pacific

Operations trick, and Signal Service Battallion (soldiers 

and Waves), approximately 1943. The battalion was 

located in Vint Hill Farms Station, Virginia. 

(Note the barn in the background.)
13

area as “highly skilled technicians” and their work to be of a 

highly secret nature.28

Even though many WAVES expressed a desire to go, the 

law did not allow WAVES to be stationed overseas, not even in 

Hawaii. OP-20-G male personnel were stationed throughout 

the world, but only a handful of women were assigned outside 

the contiguous United States. Most WAVES working in cryptography were assigned to the Naval Annex on Nebraska Avenue in 

Washington, D.C. By February 1944 nearly 3,000 WAVES were 

stationed there.29 Some WAVES worked in cryptanalysis, communication security, or translation. However, the majority of 

the women operated the cryptanalytic Bombes.

Life was not always easy for the women. Shift work duties 

interrupted regular sleeping and eating habits, which led to 

health-related problems. Women working the midnight to 

8:00 A.M. shift found it difficult to sleep while their barrackmates conducted normal daytime activities. For the Wacs, only 

Arlington Hall managed to arrange cubicle housing, placing 

four women in a cubicle rather than in barracks.30The Navy’s 

WAVE Quarters “D,” across the street from their communications facility, had several barracks to house more than 4,000 

WAVES. Each of the four original buildings housed over 100 

women on two floors. Eighty-four women shared one large 

room. They slept in bunk beds and kept their belongings in a 

steel locker. Realizing that morale was highly dependent on living conditions, the Navy built cubicle-style housing as Quarters 

“D” expanded.31 

One of our biggest problems was that of shift workers...we had 

to watch their health carefully. There was always the danger of 

emotional upsets caused by difficult sleeping arrangements.

32

Throughout the Signal Corps, Wacs’s illnesses appeared to 

be related more to the hours than to the work itself. However, 

some preferred to blame the stress on the need for accuracy and 

security.
14

The only major problem in WAC employment encountered by 

the theater was that of the Signal Corp Wacs. By midsummer 

of 1944, women in this work began to suffer from fatigue and 

depression; their sick rate was twice as high as other Wacs’, 

and morale was low. The theater chief signal officer diagnosed 

the fatigue as ‘resulting from working long hours over a period 

of several months under pressure caused by the necessity for 

speed and security in handling messages, and the realization 

of the operational importance of every duty they perform’. 

WAC and Medical Corps officers felt that the difficulty was 

due, not to the work itself, but to the lack of leaves or furloughs, the rotating shifts so short that sleeping habits never 

became adjusted, and the long hours of off-duty training in 

other Signal Corps work.33 

WAVE Lieutenant Sylvia Rosenwasser and Commander 

McDonnell corroborated the opinion that living conditions, and 

not the work itself, caused the problems. They confirmed that 

the WAVES on the Bombe deck were feeling stress not from 

their work but rather from the lack of privacy and the adjustment to a different lifestyle.34 Also, civilian women performed 

many of the same duties as some Signal Corps Wacs and yet 

were not sick as often. The major difference was that civilians 

ate and slept regularly, took routine vacations, and lived in private housing.

Living conditions for Wacs stationed overseas were frequently less than desirable. They lived in whatever facilities 

were available–schools, factories, local homes, but mostly in 

tents.

The Wacs stationed in the Southwest Pacific area suffered 

the most. The climate in New Guinea and similar regions was 

extremely hot and humid. Supplies of lightweight uniforms 

were nearly unavailable, and Wacs were forced to wear heavy 

winter clothing. The women wore long pants to protect against 

malaria-carrying mosquitoes. But the perspiration and damp 

clothing resulted in a higher rate of skin diseases. Rather than 
15

wear all the protective clothing and suffer the heat, some women chose to take their chances with the mosquitoes. As a result, 

women contracted malaria more often than their male counterparts, who were issued the long, yet lightweight uniforms.35

Despite the stress, monotony, heat, noise, lack of privacy, 

and hours of their work, women in cryptology enjoyed their 

work and their military duty. Lieutenant Rosenwasser remembers, “They were very devoted and very caring and [had] a wonderful esprit de corps. They were proud of their uniforms and 

proud of being in the navy.”36

Epilogue

Few memoirs written by Wacs and WAVES conducting cryptologic work include details of their jobs. This is 

undoubtedly due in some part to the ingrained need for secrecy. 

Some made note of the difficulty sleeping during the day, others 

of the harsh overseas climate. But these are only small passages 

in their books. Most remembered and wrote about the lifelong 

friendships they developed and the enjoyable hours they spent 

exploring the cities and villages near their stations. For these 

young women, their time in the service was an opportunity to 

experience people, places, and, in some cases, cultures they 

could never have seen at home.

While many of the civilian women remained to carry on the 

work of providing and protecting vital information, most servicewomen chose to leave the cryptologic field at the conclusion 

of the war. They, like their brothers, husbands, boyfriends, and 

neighbors, had done their part to serve their country. A WAC 

commander reported, “When demobilization came, my women 

swore they would never come back to the War Department or to 

shift work, but about 25 percent eventually did–as civilians.”37 

Even though the servicewomen were happy to leave, they were 

still quite proud of the work they had done.

I feel that what I did was worthwhile in helping to win the war, 

even realizing at that time I was merely a tiny, tiny cog in the 
16

wheel. The breaking of the Japanese code was our finest hour, 

and I will always be proud of being part of that, small as my 

part was.38

Thousands of women helped to win World War II through 

their cryptologic efforts. Few will know the significance of their 

contributions or of the lives they helped save. Although women 

have long been a part of cryptologic history, even before the 

Second World War, the presence of servicewomen in cryptology 

allowed others to follow. Their dedication and abilities proved, 

to more than one doubting male commander, that women could 

more than adequately do this exacting, detailed, and important 

work. They left behind a strong legacy, allowing thousands of 

women to follow in their footsteps. These women played vital 

roles throughout the Cold War era and will continue to bring 

their talents, skills, and abilities to cryptology, one of the nation’s 

most secret sciences.

Notes:

1. The Army’s cryptographic office changed names several times 

throughout its history. For clarity, this brochure will refer to it as 

the Signals Intelligence Service.

2. Frank B. Rowlett, The Story of Magic: Memoirs of an American 

Cryptologic Pioneer, Laguna Hills, CA: Aegean Park Press, 1997.

3. Frank Rowlett in a conversation with the curator of the National 

Cryptologic Museum, June 14, 1997.

4. The WAAC became the Women’s Army Corps (WAC) in September 

1943. The capitalized abbreviations WAC refers to the organization, lowercase Wac refers to its members.

5. Lucy Greenbaum, “10,000 Women in U.S. Rush to Join New Army 

Corps,” New York Times, 28 May 1942.

6. Judith A. Bellafaire, The Women’s Army Corps: A Commemoration of World War II Service, CMH Publication 72-15 (Carlisle, PA: 

Center for Military History), 4.
17

7. “Wave Applicants Swamp the Navy,” New York Times, 13 August 

1942, 22, col.2.

8. The Origin and Development of the Army Security Agency 1917-

1947 (Laguna Hills, CA: Aegean Park Press, 1978), 31.

9. The Origin and Development of the Army Security Agency 1917-

1947, 21, 29-30. The Second Signal Service Battalion also had name 

changes throughout the war, but this paper will always refer to it as 

a battalion.

10. Mattie E. Treadwell, The Women’s Army Corps (Washington, DC: 

Office of the Chief of Military History, Dept. of the Army, 1954), 

314-315. (Hereafter referred to as WAC.)

11. Navy Department, Communication Security Section, Memorandum for OP-20-WP, dated 1 January 1942.

12. The Origins and Development of the Army Security Agency 1917-

1947, 33.

13. “Confidential Work is Waiting for WACs,” New York Times, 17 July 

1944, 12, col. 4.

14. Navy Dept., Memorandum for Applicants for the Proposed Women’s Naval Auxiliary Reserve Corps, dated 17 July 1942.

15. OP-20-G WAVE History, Naval Security Group WAVE folder.

16. George R. Thompson, Dixie R. Harris, Pauline M. Oakes, and 

Dulaney Terrett, The Signal Corps: The Test, (Washington, DC: 

Office of the Chief of Military History, Dept. of the Army, 1957), 

204.

17. Frederick O. Musser, “Ultra vs. Enigma.” The Goucher Quarterly, 

1992, 70:2 4-7.

18. Ibid.

19. RADM Edwin T. Layton, USN (Ret.), And I Was There (New York: 

Wm Morrow & Co., 1985), 58.

20. Mary Bromble, Interview with author, 12 October 1996.

21. Elizabeth Allen Butler, Navy WAVES (Charlottesville, VA: Wayside Press, Inc., 1988), 41.
18

22. Musser, “Ultra vs. Enigma.”

23. Georgia Ludington, Interview with author, 9 May 1996. National 

Security Agency Oral History 36-96.

24. Gilman McDonnell, Interview with author. National Security 

Agency Oral History 08-96.

25. Treadwell, WAC, 316.

26. Ibid., 318.

27. Wacs were sent to Australia to work for Central Bureau Brisbane. 

For more information on that activity, see Quiet Heroes of the 

Southwest Pacific Theater, published by the Center for Cryptologic 

History.

28. Treadwell, WAC, 435. Citing Col. Westray B. Boyce report to Chief 

of Staff, USA, following her visit to the overseas theaters after the 

war.

29. Historical Review of OP-20-G, SRH-152 (1944), 2.

30. Treadwell, WAC, 319.

31. Butler, Navy WAVES, 58-9.

32. Treadwell, WAC, 319.

33. Ibid., 369-70.

34. Sylvia Rosenwasser and Gilman McDonnell, Interviews with 

author. National Security Agency Oral History 36-96.

35. Bellafaire, The Women’s Army Corps, 14-15.

36. Sylvia Rosenwasser, Interview with author. National Security 

Agency Oral History 36-96.

37. Treadwell, WAC, 321.

38. Butler, Navy WAVES, 90.