CHAPTER 4

He Who Fears Is Half Dead

and then begins step step leap
she continues these leaps
scramble the code scramble uphill scramble eggs
and without premeditation but in full arc if possible
have a good time.

—ANNE CARSON

The intercepted and decoded telegram burned its way from hand to hand, from junior diplomat to senior diplomat, first in London and then in Washington, producing involuntary noises of surprise and bulging eyes. It was obvious that the president himself needed to see it. At 11 A.M. on February 27, 1917, the U.S. secretary of state, Robert Lansing, carried a copy of the intercepted telegram to the White House and showed it to Woodrow Wilson. The president read it and grew uncharacteristically angry: “Good Lord!” he said. “Good Lord!”

The telegram had been sent from Germany to Mexico on January 16, traveling by three separate telegraph routes and encoded as a series of number blocks: 130 13042 13401 8501 115 3528 416 17214. The British had intercepted the message, and a small team of civilian codebreakers toiled for a month in a secret office inside Whitehall to scrub away the grime of code and make the plaintext visible. What they saw, to their shock, was nothing less than a conspiracy plot against the United States.

Written by Germany’s foreign minister, Arthur Zimmermann, the telegram proposed an alliance between Germany and Mexico: “We intend to begin unrestricted submarine warfare on the first of February. We shall endeavor in spite of this to keep the United States neutral. In the event of this not succeeding, we make Mexico a proposal of alliance on the following basis: make war together, make peace together, generous financial support, and an understanding on our part that Mexico is to reconquer the lost territory in Texas, New Mexico, and Arizona. The settlement in detail is left to you.”

The Zimmermann Telegram, as it came to be known, was indisputable proof of a German plot against America, “clear as a knife in the back and near as next door,” as the historian Barbara Tuchman has put it. Residents of Texas were particularly displeased to learn that the Kaiser was trying to give them to Mexico, but outrage against Germany was general across the States. The telegram sped up history. It pushed America into war with Germany, whether America was ready for war or not.

It was not.

And this is how the telegram changed the destinies of Elizebeth Smith and William Friedman: as American codebreakers, they happened to possess an extraordinarily rare and suddenly indispensable set of skills.

Elizebeth got word in January 1917 that her mother, Sopha, long ill from cancer, was on the verge of death, and Elizebeth should come to Indiana to say goodbye. She packed a bag and rode the train back to Huntington and her childhood home. Her father was there, and her sister, Edna. The two sisters consoled each other as physicians prowled through the old house, murmuring about a growth. Sopha was in a lot of pain and vomited violently. A doctor turned her on her belly and spread iodine across her back. He used cocaine to numb a particular spot and tapped a metal rod into the skin, removing what Elizebeth felt was a horrifying quantity of pinkish fluid.

She had brought some cipher materials with her, hoping to get work done. “My book-bag lies here unopened,” she wrote to William at Riverbank. “I try to make myself work, but I cannot. I sit a moment, then spend the hours pacing back and forth from Mother’s bed, in the vain hope that there is something I can do. It is so awful—Billy Boy—to look on the face of death like that—the beckoning face—Do you know it makes me think a lot about posterity, and responsibility, and all that?” She wasn’t sure what to call William in these letters, or to call herself in relation, so she mostly kept things platonic, signing her letters “yours, Elsbeth,” and thanking William for being “one of the truest friends I’ve ever had,” although she did admit that she missed William’s “rocking,” his comforting way with a rocking chair, and in one letter she slipped in something stronger: “I love you / Elsbeth.”

When Sopha died, in February 1917, Edna stayed behind to arrange the funeral, while Elizebeth returned to Riverbank, seized by a new impatience. She had no desire to spend any more time on the Bacon ciphers. Life was too short to waste on fruitless quests. When she reunited with William, he said he felt the same. They both agreed they had to remove themselves from the project. The question was how.

Confronting Mrs. Gallup seemed a little cruel. She had worked too many years in a single direction to admit her compass was broken. She had treated both of them with kindness. They tried talking to Fabyan instead. On a few occasions the two youngsters buttonholed him and tried to get him to listen. Mrs. Gallup’s theory was unsound, they said. Fabyan’s money might be better spent on other projects. He shouted them down, as they expected. Fabyan said he wasn’t paying them to question the theory, only to persuade the academy that it was correct.

But by now, even if he didn’t want to admit it, a new scheme was diverting Fabyan’s attention from the literary ciphers. Shakespeare, Bacon, Mrs. Gallup, old books, dead men—it paled in urgency to the world of the living.

For months now Fabyan had been advertising his patriotism and his willingness to place Riverbank at the disposal of the flag. He had ordered his groundskeepers to expand the network of model trenches next to the Lodge, and after months of digging by a team of mud-spattered workers the trenches reached a total length of three miles, enough to be useful for the Fox Valley Guards to conduct infantry drills complete with live mortar rounds. And Fabyan had told officials in Washington that if they needed help with codebreaking, Riverbank stood ready to serve.

“Gentlemen,” he wrote to Washington on March 15, 1917, “I offer anything I have to the government, and if you care to have any of your local men call on me, and see the work that is being done, I should be very glad to show it to them.” He described his interest in old ciphers, especially the biliteral cipher of Francis Bacon, and added: “To avoid any possibility of being considered a crank, or a theorist, I respectfully call your attention to the fact that I was the business partner of the late Cornelius N. Bliss, formerly Secretary of the Interior, whom most of the older men in Washington remember with a great deal of respect and admiration.”

Military officials were of course reluctant to give any power or responsibility to a fake colonel in Illinois, but they had little choice but to accept Fabyan’s offer. They were desperate for codebreakers because of the way radio and wireless technology was changing the art of war.

In earlier conflicts, codebreakers had mattered less; fewer military and diplomatic messages were encrypted because the messages were harder to intercept. If you wanted to steal an enemy message, you had to capture a messenger on horseback, or open an envelope at a post office, or install a tap on a telegraph wire. But with radio, all it took to intercept a message was an antenna. The air was suddenly full of messages in Morse code, dots and dashes that registered as audible pings and whines. You could pluck them out of the sky. So to protect their secrets, armies had begun encrypting their wireless messages before sending them over the wireless in Morse.

This simple fact transformed codebreakers from disreputable freaks into potential superheroes, wizards with power over life itself. Now the air was full of encrypted information of enormous tactical significance and the utmost stakes. The routes of ships at sea. Troop movements on the ground. Airplane sightings. Diplomatic negotiations and gossip. Reports of spies. Thousands upon thousands of puzzles zipping through the atmosphere, any one of which, if decrypted, might win or lose a battle, wipe out a regiment, sink a ship. In this new world, a competent codebreaker was suddenly a person of the highest military value—a savior, a warrior, a destroyer of worlds.

And yet, as Elizebeth would later write, “There were possibly three or at most four persons” in the whole United States who knew the slightest thing about codes and ciphers. She was one of them, William another.

The government lacked the capacity to reliably intercept foreign messages, much less break the codes and read them. The CIA didn’t exist in 1917. There was no NSA, and the FBI was a crumb of its future self, a nine-year-old organization known as the Bureau of Investigation, which fielded only three hundred agents, on a total budget of less than half a million dollars. There simply was no intelligence community as we think of it today. The Department of Defense was called the War Department then, which operated the army, and though the War Department did contain an intelligence-gathering section, the Military Intelligence Division (MID), it was tiny and underfunded. On the day Congress declared war, April 6, 1917, the MID employed just seventeen officers. The officer in charge of the MID, Major Ralph van Deman, considered the government’s ignorance of codes and ciphers an “emergency.”

So, in the second week of April, the War Department dispatched an emissary to Riverbank, an army colonel named Joseph Mauborgne, to check out the place and report back on its suitability.

Mauborgne was one of the three or four people in America who knew something about codebreaking. In 1912, while stationed at the Army Signal Corps School in Kansas, a bare-bones airfield and laboratory to probe radio technology, Mauborgne had made history by figuring out how to send a radio signal from a plane to the ground for the first time, and in 1914 he became the first American to break the British army’s field cipher, known as the Playfair Cipher, based on a table of letters arranged in a five-by-five grid.

When Mauborgne arrived at Riverbank, Fabyan greeted him with the usual overwhelming gusto and brought him to the second floor of the laboratory building, declaring with a flourish that the Riverbank Department of Ciphers was open for business. The office appeared busier and more crowded than it had ever been. In anticipation of the army man’s visit, Fabyan had gone out and hired a dozen clerks, stenographers, and translators fluent in German and Spanish, to provide support for Elizebeth and William. Fabyan hoped the two young people would be able to lead the effort, to break codes for the government, while Mrs. Gallup continued her long labors on the Bacon ciphers. Superficially, the office looked like the picture in Fabyan’s imagination, the pitch he had sold to Washington. It looked like a codebreaking agency on the prairie.

There in the new Department of Ciphers, Elizebeth and William introduced themselves to Mauborgne. They clicked with him immediately. He was thirty-six and big—big body, big voice, big brain, with perfectly round, black glasses. He was the only man they had ever seen stand eye to eye with Fabyan and not seem intimidated. Mauborgne liked Elizebeth and William, too. He saw a spark in the pair of young codebreakers. (He would later call them “the two greatest people I have ever known.”) They had little formal training but were bright and eager. Fabyan made him wary—a mess of a man, lunging wildly from promise to promise—but it was undeniable that Riverbank had excellent security from a military standpoint. Aside from the virtue of being in the middle of nowhere, safe from enemy attack, it was protected by the lighthouse, and Fabyan also had the Fox Valley Guards nearby—his own private army. If all else failed and the Germans invaded, Fabyan said he would open the bear and wolf cages in the garden and sic the beasts on the intruders.

On April 11, Mauborgne informed his commanders that Riverbank was ready. He urged the army and also the Justice Department “to take immediate advantage of Colonel Fabyan’s offer to decipher captured messages,” owing to “the mass of data” in his private library of cipher books, the security of his compound, and the quality of his employees, “a force of eight or ten cipher experts who spend their time delving into the works of antiquity, discovering historical facts hidden away.”

After reading Mauborgne’s enthusiastic report, Van Deman of the MID wrote to Fabyan with gratitude, thanking him for “your exceedingly kind and patriotic offer of assistance,” and soon encrypted messages started arriving at Riverbank from Washington. They came in the mail and by telegram, sent by different parts of the government: the War Department, the navy, the Department of State, the Department of Justice. The messages had been intercepted by covert means, mostly from various telegraph and cable offices across the country.

Fabyan had gotten his wish: for the foreseeable future, Riverbank would become ground zero for military codebreaking in America, a de facto government agency. He had drafted Elizebeth and William into the war, assuming they would be able to handle what was coming. But when they looked at the messages, the fresh piles of gobbledygook spilling from the mail sacks onto their desks, they weren’t sure that he was right.

A woman and a man are sitting side by side in a busy room. People come and go and the door opens and closes and there is the sound of typewriter keys smacking ink into pages. Outside the window, hawks fly and cows moo and a bear scratches himself in an iron cage and a parrot sings and a river runs and there are also monkeys in diapers for some reason.

The two people, Elizebeth and William, notice nothing except what is in front of them on a slab of desk. They are looking down at a sheet of paper. All of their intensity is shining down at the paper, a bright beam of desire to understand the text that is typed there.

It looks like nothing. It is clearly not written in the biliteral cipher of Francis Bacon that they are familiar with. It is something else, a new level of mystery. They must understand it. But they don’t know what they are looking at.

BGVKX	TLXWB	SHSFW	KWGRI	KZTZG
RKZFE	YDIWT	KOFOB	GUHGD	SFVRE
UIUQX	HSLDS	OHSRM	HTWKY	VHUIK
BJDUH	VSART	BGVNG	VBAFO	AZOXG
PQPMJ	DRODW	RCNML	MTMXL	SSVAR

A hiss of symbols, a raw block of babble. A cryptogram. Someone wrote and sent it for a purpose, and someone else intercepted it, and now it is here on your desk. These letters contain meaning. How to unlock it without knowing the key?

The basic task of codebreaking might seem impossible if you think about how many different ways a message might be encrypted. Each human language has its own quirks and curiosities. Then, within each language, a cryptographer can choose from among dozens of varieties of locks—codes and ciphers. And each lock will accommodate only one of a vast array of possible keys.

For instance, one of the simplest kinds of ciphers, called a mono-alphabetic substitution cipher, or MASC, swaps out one set of letters for another. Perhaps A=B, B=C, and C=D, or perhaps A=X, B=G, and C=K—or any other map between the 26 letters of the plaintext alphabet and 26 different letters in the ciphertext. A MASC is a very basic method of encrypting a message. But even here, there are 403,291,461,126,605,635,584,000,000 potential alphabets: 403 septillion. A thousand computers, each testing one million alphabets per second, would take more than a billion years to exhaust the possibilities.

And yet anyone who has ever solved a cryptogram on a newspaper puzzle page has conquered the 403 septillion possibilities, because, of course, there are shortcuts, ways of taming the task by grabbing on to certain patterns in the text.

This is the essence of codebreaking, finding patterns, and because it’s such a basic human function, codebreakers have always emerged from unexpected places. They pop up from strange corners. Codebreakers tend to be oddballs, outsiders. The most important trait is not pure math skill but a deeper ability to pay attention. Monks, librarians, linguists, pianists and flutists, diplomats, scribes, postal clerks, astrologers, alchemists, players of games, lotharios, revolutionaries in coffee shops, kings and queens: these are the ones who built the field across the centuries and pushed the boundaries forward, stubborn individuals with a lot of time to sit and think and not give up.

Most were men who did not believe women intellectually or morally capable of breaking codes; some were women who took advantage of this prejudice to steal secrets in the shadows. One of the more cunning and effective codebreakers of the seventeenth century was a Belgian countess named Alexandrine, who upon the death of her husband in 1628 took over the management of an influential post office, the Chamber of the Thurn and Taxis, which routed mail all throughout Europe. The countess had a taste for espionage and transformed the Chamber into a brazen spy organization, employing a team of agents, scribes, forgers, and codebreakers who melted the wax seals of letters, copied their contents, broke any codes, and resealed the letters. This was an early example of what the French would later call a cabinet noir, or black chamber, a secret spy room in a post office. The countess’s male contemporaries were slow to discover her true occupation because they couldn’t imagine that a woman was capable of such deceptions. “What if this countess does not merely open our letters but is also capable of deciphering their contents?” one diplomat wrote in panic to another. “God knows what she is capable of doing to us!”

The two most prominent codebreakers in America when Elizebeth and William started were a married couple, Parker Hitt and Genevieve Hitt. Parker was a tall, dashing Texan with weathered skin, an army infantry commander in his thirties who had gotten interested in cryptology after volunteering to fight in the Spanish-American War and trying his hand with messages intercepted from the Mexican army. His wife, Genevieve, a proper southern girl, had scandalized her family by falling in love with a man they saw as a cowboy. She also studied cryptology, eventually becoming chief of the code operation for the War Department’s Southern Division, based in San Antonio. “This is a man’s size job,” she wrote to her mother-in-law, “but I seem to be getting away with it, and I am going to see it through. . . . I am getting a great deal out of it, discipline, concentration (for it takes concentration, and a lot of it, to do this work, with machines pounding away on every side of you and two or three men talking at once).” Parker supported Genevieve and was proud of her: “Good work, old girl,” he wrote to her in one letter.

Parker was the only American to have written a serious book about cryptology. Aimed at army units with no prior training, Manual for the Solution of Military Ciphers showed how to set up a quick-and-dirty deciphering office in the field with five or six soldiers, some radio equipment to intercept enemy signals, and a day or two of study. Hitt went over the basics of military cryptography and explained, accurately, that the methods of the world’s armies had not changed much in hundreds of years. Just like there are millions of chicken recipes in the world but only several basic methods to cook the bird (roasting, frying, poaching, boiling), there are countless ciphers but only a handful of common types. Then he laid out some basic steps for solving a cryptogram written in cipher. Today a computer could do any of these steps in picoseconds, but in 1917 it all had to be done by hand, with a pencil and paper.

The first step was usually very simple: count the letters in the cryptogram. In English, the most frequently used letter is E, the most frequent two-letter group is TH, and the most frequent three-letter group is THE. So if you count the letters in the ciphertext and the most common letter is B, it might stand for E, and if the most common three-letter group is NXB, it might stand for THE.

You can count other things in a cryptogram, like the total number of vowels and consonants, and how often particular letters or groups of letters appear before or after other letters. All of these counts give hints to the hidden structure. A frequency count can also reveal if the plaintext was written in English, German, French, Spanish, or some other language, because the frequency of letters in a language is like a unique signature. The most common six letters in German, starting with the most common, are E, N, I, R, T, S. In French, E, A, N, R, S, I. In Spanish, E, A, O, R, S, N.

It’s best to do the counting in a systematic way. You might start by drawing a thing called a frequency table. You chop the cryptogram into its component parts and sort them according to the letters by which they’re surrounded. It looks like this:

Though it may look like gibberish, it’s a powerful tool—“the Real Stuff,” in Elizebeth’s phrase—because with a quick glance down the columns, you can identify the most frequent letter groups in the cryptogram and the letters that come before and after them. Letters in a given language are like children in a kindergarten class; they have affinities, cluster in cliques. In the lunch line, one kid likes to walk behind a second kid and in front of a third kid while a fourth sits off in the corner, eating from a paper bag. What you’re really looking at when you look at this frequency table is a picture of “certain internal relations in the English alphabet,” as Elizebeth and William would put it. You’re looking at the structure of the underlying language itself.

Now you have some grip on the puzzle. You can begin to peel back the skin of the message, to see familiar shapes in the strangeness. Like with a crossword puzzle, there’s no direct, guaranteed route to solving a cryptogram. The solver has to make educated guesses, plug in letters and see if they lead to recognizable words, backtrack and erase if a guess is wrong, try a new letter.

Elizebeth quickly got the hang of it, plowing through messages and counting letters, although it felt completely new and weird to her, a totally different way of looking at language than what she was used to. All her life she had celebrated the improbable bigness of language, the long-lunged galaxy that exploded out from the small dense point of the alphabet, the twenty-six humble letters. In college she trained herself to hear the rhythms of playwrights and poets, the syllables that slip from the tongue in patterns. Tennyson:

There lives more faith in honest doubt,

Believe me, than in half the creeds.

There LIVES more FAITH in HON-est DOUBT,

Be-LIEVE me, than in HALF the CREEDS.

But before, she had gone no further than chopping lines into meters. She left the words in their boxes, intact. Codebreaking required more drastic measures. Now Elizebeth had to shake the words until they spilled their letters. To rip, rupture, puncture, chisel, scissor, smash, and scoop up the rubble in her arms. To chip off flakes from the smooth rock of the message and place them in piles and ask questions about them. It involved a kind of hard-hearted analytic violence that she had never contemplated before. It was reaching into the red body of the text until the hands dripped with blood.

Ahhhh!

The first few messages she broke, real military messages, had been intercepted from the Mexican army. Like most military cipher messages, they were written in blocks of five letters, like TZYTV RGFQF MQFHC, in order to fuzz out the original lengths of the words and therefore make the messages harder for adversaries to break. Elizebeth counted the letters, drew her frequency tables, consulted materials on the frequencies of various letters and letter combinations in the Spanish language, scratched her guesses into the graph paper, and there, right there—she saw things that started to look like words. A lovely shape pried out of the murk, glistening.

The process gave her a sensation of power that was electric and new and made her want to keep going. It was nothing like working on the biliteral ciphers with Mrs. Gallup. Here there was no mystery, no squinting through a looking glass at the curls of italic letters and trying to sort them into categories based on vague criteria never fully explained. Here the method was sharp and clear, a series of small and logical steps that built toward a goal. “The thrill of your life,” Elizebeth said later, describing how it felt to solve a message. “The skeletons of words leap out, and make you jump.”

And she was never alone. That was the other thrill. She and William operated as a team. During the day they were never more than a few feet apart, handing papers back and forth, checking each other’s work, asking questions when stuck, keeping up a friendly patter, “calling out” letters on their sheets in the “word-equivalent” alphabet commonly used by the U.S. Army: Able for the letter A, Boy for B, Cast for C, Dock, Easy, Fox, George, Have, Item, Jig, King, Love. If Elizebeth needed to read the ciphertext FVGEQ, she would call out, “Fox! Vice! George! Easy! Quack!”

It was demanding work. Each solution had to be checked. Errors corrected. A single miscopied letter could wreck hours of effort. You got tired and needed a friend to look at your page while you rubbed your eyes. Each learned to recognize signs of fatigue in the other and knew when to suggest that it was time for a break. The less you had to think about, the better and more accurate your work. Elizebeth and William used the same kind of pencil, the same kind of paper, and never deviated from these choices. They liked pencils with soft lead and big erasers, the eraser end seeing as much action as the lead end.

Cast! Easy! Jig! King! Opal! They called out letters all day long like teachers taking attendance at a strange school. Pup! X-ray! Vice! Love! Sail! The pencils at Riverbank were plentiful and free, black with white erasers, and doubled as advertising tools; a cipher alphabet was printed on each pencil in white letters, along with RIVERBANK LABORATORIES—GENEVA, ILLINOIS.

Mike, she called out, a smile playing at the corners of her mouth. Zed. Rush. Fox. Zed.

Watch, he called out, grinning. Dock. Yoke. Pup. Easy.

The paper they used was graph paper with a grid of quarter-inch squares. One letter per square. They never threw anything out. “Work sheets SHOULD NOT BE DESTROYED,” the pair would soon write in one of several scientific papers about their discoveries. Worksheets “form a necessary part of the record pertaining to the solution of the problem. No work is too insignificant to discard, therefore it should be done well from the start.”

Tare. Yoke. George. George. Able.

Unit. King. Nan. Zed. Boy.

No one told them how to set up this workflow, and no one told them they had to collaborate. They simply found, by trial and error, that collaboration made things go faster, that “a group of two operators, working harmoniously as a unit, can accomplish more than four operators working singly. Different minds, centered on the same problem, will supplement and check each other; errors will be found quickly; interchange of ideas will bring results rapidly. In short, two minds, ‘with but a single thought,’ bring to bear upon a given subject that concentration of effort and facility of treatment which is not possible for one mind alone.”

Although William and Elizebeth solved their first batches of military messages using techniques they learned from Hitt’s manual, they soon exhausted its teachings. Elizebeth filled the margins with her own notes in blue pen, comments about sentences she found imprecise, things Hitt had gotten slightly wrong, things he could have explained better or had left unexplored. (She underlined a sentence on page 85 and wrote next to it, “This is poorly expressed.”) She and William had reached the cordon of what was known, the edge of the map. From here on, they would need to invent new techniques—to become scientists, explorers, pushing into a wild land.

One way of thinking about science is that it’s a check against the natural human tendency to see patterns that might not be there. It’s a way of knowing when a pattern is real and when it’s a trick of your mind. Elizebeth and William had begun at Riverbank by looking for the false patterns of Mrs. Gallup. But now, over the next several years, they found ways of seeing true patterns. It was as if they had been tossed into a raging river of delusion without knowing how to swim and figured out how to save themselves from drowning, clinging to each other the whole time. This struggle made them stronger than they could have ever imagined. They climbed out of the river transformed, with new powers, shaking the water from their backs, and then took off at speed, racing across the mountains and through the swamps of an undiscovered continent.

Between 1917 and 1920, George Fabyan used Riverbank’s vanity press to publish eight pamphlets that described new kinds of codebreaking strategies. These were little books with unassuming titles on plain white covers. Today they are considered to be the foundation stones of the modern science of cryptology. Known as the Riverbank Publications, they “rise up like a landmark in the history of cryptology,” writes the historian David Kahn. “Nearly all of them broke new ground, and mastery of the information they first set forth is still regarded as the prerequisite for a higher cryptologic education.”

The eight Riverbank Publications are commonly attributed to William alone, with two exceptions. Inside his personal copy of one paper, Riverbank No. 21, Methods for the Reconstruction of Primary Alphabets, William wrote in black ink beneath the title, “By Elizebeth S. Friedman and William F. Friedman.” A second paper, Methods for the Solution of Running Key Ciphers, never included her name, but she and William always told colleagues it was a joint effort.

However, there’s evidence that Elizebeth was involved with more than just the two papers. The original typewritten and hand-edited drafts of the Riverbank Publications are now held by the manuscript division of the New York Public Library, and her handwriting is all over them. William seems to have written a lot of the technical sections, with the drafts marked up by both of them, Elizebeth’s comments interspersed with his, while Elizebeth wrote and researched the historical sections, which he edited in a similar fashion.

They worked as a team in most matters and the soon-to-be-legendary papers were no different. In a 1918 letter to Elizebeth, William referred to the early Riverbank Publications as “our pamphlets”—our, not my. And other Riverbank workers contributed as well: men and women, codebreakers and translators. The publications were “a piece of work that was done by the staff,” Elizebeth said later. “No one person was mentioned as the sole conqueror or anything like that. Everybody worked together.” This is as far as she ever went in claiming a piece of the credit. Today it’s hard to know exactly what she did, because she wanted it that way. “Mrs. Friedman had a tendency to see that the record made little or no mention of her contribution to a number of their joint efforts,” the custodian of the Friedmans’ personal papers wrote in 1981 to a researcher interested in Elizebeth. “And therefore it will be difficult to get a clear picture of her exact role.”

Why hide her role? Partly it was expected at the time, that the man was the scientist and the woman the helpmate, but Riverbank was a bubble world where the usual rules didn’t apply. Fabyan had no trouble championing the work of women, as he proved with his zealous promotion of Mrs. Gallup. A more likely explanation is that Elizebeth was trying to help William win a battle with Fabyan over the copyrights of the Riverbank Publications. At first, Fabyan didn’t even let William place his name on the covers of the pamphlets, only on the inside pages, and Fabyan registered the copyright under his own name. He said he saw no ethical problem because he had paid for the research. “It may be egotism on my part,” Fabyan told William, “but so long as I pay the fiddler, I am going to have the privilege of selecting a few of the tunes.”

It was hard enough for William—a credentialed scientist, a genetics Ph.D.—to get credit for the work. He and Elizebeth may have decided it would be doubly hard to convince Fabyan to share credit with her, too.

Whatever the case, the Riverbank Publications, and the breakthroughs they describe, still seem incredible today. Seven of the eight pamphlets were written in the space of two years, in a little cottage in the middle of Illinois, the cryptologic equivalent of Albert Einstein’s annus mirabilis, when Einstein rewrote the language of light, mass, and time in the space of a single year, at age twenty-six, while working as a patent clerk in Switzerland, staring out the window of his office and bouncing ideas off a fellow clerk. This is the achievement that the NSA interviewer in 1976, Virginia Valaki, kept begging Elizebeth to explain: How? Elizebeth gave unsatisfying answers, noted in the transcript:

“That World War I leapt on, and so many things happened so fast. . . .”

“Nothing was ever as carefully executed as that. It was sort of on a day-to-day basis. You did what you could with what you had to do it with.”

“I don’t think I remember offhand. I was too busy either getting on this swing or getting off that one. ((Laughs.))”

“I feel no confidence whatever to speak on that point; wouldn’t have the faintest idea what to say.”

The likely truth: it only looked improbable in retrospect. At the time they didn’t know what was supposed to be hard, and there was no one around to tell them. They didn’t see themselves inventing a new science. They were playing the game day-to-day as best they could, as Fabyan always said. They were just trying to solve messages as they poured in and not get stuck.

The mail from Washington contained a frothy mix of messages from all over, a zoo of alphabets that had to be studied and classified. There were two main animal kingdoms of cipher, “transposition” and “substitution.” A transposition cipher was like Scrabble, a jumbling of the same letters into a new order. A substitution cipher was a swapping of letters. Each kingdom contained a diverse multitude of beasts that had to be tamed in different ways, and there was always a time crunch, someone demanding a quick answer. Invention under pressure.

One day in early 1917 a heavyset man showed up at Riverbank on a mission all the way from Scotland Yard, the police headquarters in London. He had been referred to Riverbank by the U.S. Department of Justice. Fabyan barked an introduction at Elizebeth and William, and the detective opened a briefcase. Stacks of messages spilled out. He said the messages had been intercepted by British postal censors, and the recipients included as many as two hundred individuals in India, then a British colony. Scotland Yard suspected an attempt by Germany to spark a revolution among Hindu separatists, but no one knew for sure. All the detective knew were the names of a few of the suspects, which he told to Elizebeth and William.

The young codebreakers looked at the messages and found them “quite baffling.” They were written in numbers, grouped together in shorter or longer blocks:

38425    24736    47575    93826

97-2-14

35-1-17

73-5-3

82-4-3

Elizebeth and William assumed from these groupings that the separatists were using three different codes. The blocks of five numbers looked like a simple type of codes based on a rectangular grid of letters:

	1	2	3	4	5	6	7
1	A	B	C	D	E	F	G
2	H	I	J	K	L	M	N
3	O	P	Q	R	S	T	U
4	V	W	X	Y	Z

The grid turns a letter into a number (C is 13), which then has a number added to it, based on a prearranged key word. If the word is LAMP, the value of L (25) might be added to C (13), making 38. Elizebeth and William deduced the key word and solved the messages by analyzing frequent numbers and the intervals between them.

Thinking about the second set of numbers (97-2-14), which were confined to a single long message in the detective’s trunk, Elizebeth and William noticed that the middle number was always either a 1 or a 2. This was a clue that the conspirators were using a specific, yet-unknown book to encrypt their messages and that the book had two columns of type, like a dictionary. The numbers likely pointed to words at certain locations in this mysterious book. For instance, in a sequence like 97-2-14, 97 meant the page number, 2 meant the right-hand column, and 14 meant the fourteenth word in the column. Applying similar logic to the third set of numbers in the detective’s messages (73-5-3, 82-4-3), the young codebreakers deduced that the numbers pointed to individual letters within a different book possessed by the conspirators. The recipient of the letter, seeing the number 73-5-3, would turn to the seventy-third page of the book, go to the fifth line, and write down the third letter in the line.

Of course, this wasn’t enough information to solve the messages, and the young codebreakers at Riverbank weren’t sure they could go further: If the letters and words had been selected from specific books, and Elizebeth and William didn’t know the names of the books or have copies of them, what was the use?

“For a time,” William wrote, “it looked like an insurmountable task.”

But they wrote down all the numbers in order, searched for repetitions, thought about it some more, and found a foothold. A Harvard professor had recently counted the words in a long English text, and the prairie codebreakers read his study. Of 100,000 total words, only 10,161 were unique, and just 10 words accounted for 26,677 of the 100,000: “the,” “of,” “and,” “to,” “a,” “in,” “that,” “it,” “is,” “I.” “You can’t convey much intelligence using only these words,” William wrote, “and yet you can’t construct a long, intelligible, unambiguous message without using them over and over again.”

Turning to the numbers that seemed to come from a dictionary, the codebreakers reasoned that a word at the beginning of the alphabet, like “and,” would correspond to a code group beginning with a lower number (1, 2, 3, 4) than a word that came higher in the alphabet, like “the.” This insight helped them solve the most frequent words in the messages, and from there it was possible to work out others: If 97-2-14 was YOU, then 99-2-17 must be a word close to “you” in the dictionary, perhaps “your,” “young,” or “youth.” Elizebeth and William ended up solving 95 percent of the message in this manner, without ever seeing a copy of the conspirators’ dictionary. As for the last set of numbers, the ones that seemed to refer to letters in an unknown book, they used a similar process, matching frequent code groups with frequent letters and pairs of letters, and reverse-engineering the text of the book as they went. Whenever they discovered a new letter of plaintext, it told them more about the content of the book, and whenever they pieced together a new line in the book, it told them more about the plaintexts of the messages. One of the conspirators’ notes read, in part:

I challenge anybody who dares ignore the solid work done through our agencies. . . . Our men worked, suffered. Still suffering. . . . We have succeeded in laying foundation for future work . . .

The two young codebreakers ended up solving the whole trunkful of messages for Scotland Yard, revealing an intricate separatist plot by Hindu activists living in New York to ship weapons and bombs to India with the help of German funds and assistance: dates, times, places, names. Several conspirators were charged in San Francisco, and prosecutors summoned William to testify in open court about how he broke the codes. Elizebeth wasn’t asked. She hated staying in Illinois while William went on an exciting trip to the West Coast—she thought she deserved to be called as a co-witness—“but someone had to stay behind and sort of oil the machinery at Riverbank.” She didn’t speculate about why William was chosen instead of her, perhaps because the answer was obvious: prosecutors thought the jury would more easily believe a male expert. As it turned out, the trial erupted in spectacle: Before William had a chance to say his piece on the witness stand, an Indian man in the gallery stood up, pulled a handgun from his vest, and shot one of the defendants in the chest. He yelled a single word—“Traitor!” Then a U.S. marshal fired at the gunman over the heads of the shocked spectators, killing him. The shooter apparently thought the defendant had snitched to the government, betraying his friends by revealing the code. He didn’t know about William, Elizebeth, and the science of codebreaking.

For the first eight months of the war, as incredible as it sounds, William and Elizebeth, and their team at Riverbank, did all of the codebreaking for every part of the U.S. government: for the State Department, the War Department (army), the navy, and the Department of Justice. And the broader scientific insights of the Riverbank Publications emerged directly from these day-to-day puzzles solved under wartime pressure. The pair would solve a cryptogram and realize they may have stumbled onto some more general method. Then they would test the method on additional examples, trying to see where it broke, what its limits were, aiming to strengthen a one-time solution into a universal principle and to share that knowledge with others.

It had long been known that the frequencies of letters in a cryptogram provide clues to its solution. Knowing this, cryptographers had invented many ways of obscuring the letter frequencies, making messages harder for adversaries to break. It was possible to encrypt a message with multiple cipher alphabets instead of just one (a poly-alphabetic cipher). It was possible to rely on a secretly chosen novel or dictionary to generate a code message, in the style of the Hindu revolutionaries. If the sender and recipient happened to select a key in their book that was exactly the same length as the message—known as a “running key”—the message became even harder to break. The War Department considered running-key messages to be indecipherable. And these methods could be mixed and matched to further frustrate the codebreaker. For instance, a plaintext word like “strawberry” could be turned into a block of code like WUBCW, then those letters transformed with a cipher into LWJIJ—a process of “enciphered code.”

Each of these techniques placed a wall between the message and the codebreaker—sometimes a pane of frosted glass, sometimes a sheet of metal or stone. Elizebeth and William invented new tools for destroying these walls—hammers, corrosive acids, explosives. They learned to identify and solve several different kinds of substitution ciphers: straight alphabets, direct alphabets, reversed alphabets, poly alphabets, mixed alphabets. They developed general techniques of solving book ciphers without needing a copy of the book. They taught themselves to solve messages enciphered with running keys. Together in Engledew Cottage they strolled through cities of text with their wrecking kit, swinging hammers with glee, blowing up brick, melting steel, the sound of breaking glass echoing out into the prairie. Then they wrote the scientific papers, the Riverbank Publications, documenting exactly how they did it, and how other people could do it, too, if they followed the same steps.

This part was crucial. The test of a scientific discovery is if others can replicate it and get the same results. Mrs. Gallup had never passed this test. Elizebeth and William wanted to pass. They later wrote, “What Colonel Fabyan failed to realize, throughout his campaign to ‘sell’ Mrs. Gallup’s decipherments, was that no demonstration, however good, can take the place of experiments which can be repeated and will produce identical results.”

To drive home this point, William even invented a new word: “cryptanalysis,” synonymous with “codebreaking.” The new Riverbank methods were not magic but a species of analysis, similar to the analysis performed by a chemist or an astronomer or an engineer designing a bridge.

Serendipity still played a role in codebreaking. “Many times,” the pair wrote, “the greatest ally the mind has is that indefinable, intangible something, which we would forever pursue if we could—luck.” Epiphanies happened. Insights that seemed to come from nowhere, bolts from the blue, guesses that made more progress on a problem than days of dreary labor. Mrs. Gallup had always called this “inspiration.” Elizebeth and William preferred to speak of “flexibility of mind” or “intuitive powers” because these phrases sounded less magical. Intuition, to them, was like a hard-earned internal compass, a grooved-in sense of how to move forward that came from patience, skill, and experience. It could be cultivated.

Starting here at Riverbank and continuing throughout their lives, people tended to describe the brains of Elizebeth and William in gendered ways, as if her style of solving puzzles had a starkly different texture than his. Elizebeth’s was usually said to be the more intuitive mind, William’s the more mathematical. He was supposed to be better with machines and she with languages—Elizebeth was rapidly picking up German and Spanish, and learning pieces of other tongues. There may have been some truth in it. But the reality is that they were both mathematical neophytes, even William. A future colleague of William’s, Lambros Callimahos, a classical flutist and trained mathematician, idolized William to the point of copying his personal habits; upon learning that William liked to use tobacco snuff, Callimahos took up snuffing. But Callimahos recognized that whatever made William good had little to do with math. He described William as a man “cursed by luck,” writing, “Even if he computed odds incorrectly, it didn’t make any difference because he would forge ahead in his blissful ignorance and solve the problem anyway. On several occasions he told me that if he had had more of a mathematical background, he might not have been able to solve some of the things he did.” If William had been older or better trained, “he could have been ruined. His definition of a cryptogram was simply a secret message that was meant to be solved, just that.”

To those who had a chance to watch them both work, the minds of William and Elizebeth appeared equally amazing and equally incomprehensible. Their brains were Easter Island statues, stony and imposing. Colleagues resorted to mystical analogies. William was like a latter-day King Midas: “Everything he touched turned to plaintext.” Elizebeth’s gift for puzzles was “God-given,” “an effect without a discernible cause.” Who was the better codebreaker, William or Elizebeth? People gave up trying to figure it out. A raffish young army officer from Virginia, J. Rives Childs, met William and Elizebeth at Riverbank in November 1917; they taught him the science of codebreaking, and he went on to serve with distinction in the war. Childs found it impossible to tell if William was smarter than Elizebeth or if it was the other way around: “I was never able to decide which was the superior.”

Elizebeth and William sometimes played into the stereotype that he was the mechanical male thinker and she the sensitive female thinker. It was a helpful shorthand for explaining the inexplicable.

There’s a now-famous story that encapsulates how they thought about their own differing brains. One day during the war, a series of five short messages arrived at Riverbank from Washington. It was a test of sorts. The messages had been encrypted with a small hand-operated device recently invented by the British army to make their field communications more secure. The device was a kind of cipher disc, with two alphabets printed on rings that rotated with respect to each other, but with a twist: while the outer ring had the usual 26 letters, the inner ring had 27. The extra letter introduced a degree of irregularity, making it harder for a codebreaker to visualize the alphabets sliding against each other. The device also allowed the cryptographer to change the alphabets quickly and easily.

The British had already concluded that the device was unbreakable. So had experts in France and a few in America. But to be certain, an official in Washington had used the device to encrypt five test messages, using two alphabets of his choosing. He then sent the messages to the Colonel, to see if Riverbank could solve them.

William looked at the messages. He had been given a description of the device that produced them, but not alphabets. His only chance to solve the messages was to reverse-engineer the alphabets the Washington official had used.

He began with the assumption that the official wasn’t an expert cryptographer: a safe assumption, because almost no one is. Therefore the official might have made any number of common blunders that people often make when trying to communicate securely. The strength of a cryptographic system usually has less to do with its design than with the way people tend to use it. Humans are the weak link. Instead of changing keys or passwords at regular intervals, we use the same ones over and over, for weeks or months or years. We repeat the same words (such as “secret”) at the start of multiple messages, or repeat entire messages multiple times, giving codebreakers a foothold. We choose key phrases that are easy to guess: words related to where we live or work, our occupation, or to whatever project we’re working on at the moment. A couple of human mistakes can bring the safest cryptographic system in the world to its knees.

It struck William that the Washington official, in preparing this important test of a cryptographic device, might have used key words related to the practice of cryptography. So William tried words like “cipher,” “alphabet,” “indecipherable,” “solution,” “system,” and “method.” After two hours of intense focus, he was able to piece together what he thought was the alphabet on the outer disc, which seemed to use the key phrase cipher. William now assumed that if the official had been careless enough to use a guessable key phrase in one alphabet, he had probably used a similar key phrase in the second alphabet too, on the inner disc. But this one proved tougher to crack. William tested all sorts of key phrases; nothing worked. He turned to Elizebeth for help.

“I was sitting across the room from him,” she recalled, “busily engaged on another message”:

He asked me to lean back in my chair, close my eyes and make my mind blank, at least as blank as possible. Then he would propound to me a question to which I was not to consider the reply to any degree, not even for one second, but instantly to come forth with the word which his question aroused in my mind. I proceeded as he directed. He spoke the word cipher, and I instantaneously responded, “machine.” And, in a few moments Bill said I had made a lucky guess.

Later, in writing and interviews, Elizebeth would try to explain the “springlike elasticity” of her mind in this moment. What led her to blurt out the word “machine”? Where did it come from? All she would say is that because the British device was small and hand operated, “it did not occur to [William’s] meticulous mind to use the word machine. But to me it was a machine.” Thanks to Elizebeth’s guess, she and William were able to solve the five test messages in less than three hours.

William attributed Elizebeth’s insight in this case to the fact that she was a woman. He later said in a lecture, “The female mind is, as you know, a thing apart.” He appears to have made a joke about sex as well. He and Elizebeth had just gotten married when this story took place. William recalled in his lecture to a roomful of men, “I came to the end of my rope and said to the new Mrs. Friedman: ‘Elizebeth, I want you to stop what you are doing and do something for me. Now make yourself comfortable’—whereupon she took out her lipstick and made a few passes with it.” Imagine laughter.

To hear Elizebeth tell it, William was the brighter one. Before they were married and before they were a courting couple, she was already starting to praise his abilities in a way that minimized or overlooked her own, setting the pattern for the rest of her life, the moments when she would describe William to friends and to reporters as a man of history and destiny, “a wonderfully warm man, with the broadest of minds and intelligence,” and even “the smartest man who ever lived.” All the same, she was competitive by nature, and at times the two of them indulged a cheerful rivalry.

Once, in a dusty 1896 issue of the literary magazine Pall Mall, William and Elizebeth discovered an article about ciphers used by anarchist opponents of the old Russian czars. The article included a brief cryptogram at the end. In general, the shorter the cryptogram, the harder it is to solve, the same way a song is harder to identify by three notes of its melody instead of twenty. This “Nihilist” cryptogram consisted of only a few numerals and two question marks:

(Hathi Trust Digital Library)

No solution was given. “The meaning of the cipher which now follows will never be solved by any one,” the author wrote, concluding that the lock “has now closed and firmly shut its fastenings.”

Naturally, William grabbed a pencil and began trying to pick the lock. “Well,” Elizebeth writes, when William “met up with that message, he took the challenge and set his teeth into the tough nut with a snap. And would you believe it, he deciphered the message, short as it was, and the key, in 15 minutes!” The key relied on a single repeated word: “courage.” The plaintext read: “He who fears is half dead.”

It’s a convincing piece of testimony to his greatness: William Friedman, the smartest man who ever lived. But instead of ending the story here, Elizebeth goes on: “Of course, when I learned that, I too had to try my hand” at the cryptogram. “I unlocked the forever-to-be-hidden secret in 17 minutes.”

By the spring of 1917, William was in agony. He had known Elizebeth for eight or nine months now and he wanted her all the time. He was afraid to say it out loud because he didn’t know if she would reciprocate. She had never called him anything but a friend. But he was sure he loved her. It was getting hard to sit with her all day and pretend to be thinking about work. In the moments when he appeared to be scratching away at a puzzle, he was really wondering what her hair would look like if he reached behind her neck and removed the pin, her beautiful loosened hair if he pulled her close.

He imagined a life with her, a house, children, and at the same time he could not imagine it. He knew that his Jewish family and friends in Pittsburgh would not approve of him marrying a non-Jew. The community there had always seen marriage between Jews and Gentiles as a kind of betrayal, a weakening of Jewish resistance to a hostile and bigoted American culture. When William was growing up, Pittsburgh’s Jewish Criterion weekly newspaper made the case against intermarriage in repeated articles and editorials:

The glacial undercurrents of racial antipathy between Jew and non-Jew cannot be tepified by even the hottest fiercest rays of the sun of love! Statistics and the divorce courts prove this.

A part cannot become merged into a whole without ceasing to be a part. The Jews don’t want to merge.

WILL THE JEWS COMMIT SUICIDE THROUGH MIXED MARRIAGES?

He feared what his people would say. But desire trampled the fear.

Soon enough, but not yet, he would tell Elizebeth what he thought of her: that “your soul and spirit and heart are as fine, sweet, and pure as your body is beautiful”; that the perfection of her body was matched only by the clockwork of her mind, “brilliant and quick and clever”; that she had him “skinned to a frazzle” in the brains department. He marveled at her ability to escape the bounds of a problem, to strike the flint of her thoughts against different rocks, against history and math and logic and against William, too, shooting out sparks, ribbons of flame. “You’re lots smarter than I am in ciphers. You can soar away into the clouds and still remain planted firmly upon solid ground and reason. You can dream and be practical.” He would tell her, over and over, that he couldn’t express what was in his heart: “Oh Divine Fire Mine, I adore you, how futile are words!”

Divine Fire. A nod to the Bible of his father. The devouring God of the Old Testament, whose fire is in Zion, and his furnace in Jerusalem.

One of the mysteries of falling in love is that it makes you inarticulate and eloquent at the same time. You lose the ability to speak and write in normal ways (How futile are words!) even as you develop, with this person you love, assuming this person loves you back, a shorthand of glances and gestures. At first it seems like your beloved is “speaking in code”; later, maybe, it’s like the two of you are sharing a secret code.

This feeling may have a deep scientific explanation. In the 1930s and ’40s, before the digital computer was invented, a young scientist from rural Michigan named Claude Shannon wrote two papers that were like magic beans for the computing revolution, growing the great beanstalks of IBM, Apple, Silicon Valley, the Internet. As a graduate student at the Massachusetts Institute of Technology, Shannon realized that electronic circuits could be arranged to solve logic problems and make decisions, and that 0s and 1s could encode all the world’s information, from a song to a Van Gogh. He didn’t create the first computer, but he was one of the first to grasp the immensity of what digital computers could do.

Shannon, who would later work with William Friedman and other cryptologists on secret NSA projects, also enjoyed thinking about codes and ciphers. While employed at Bell Labs, he came up with the insight that the problem of communicating through a noisy system, like a phone wire, is almost identical to the process of enciphering and deciphering a message. In other words, according to Shannon, making yourself understood to another person is essentially a problem of cryptology. You reduce the noise of the channel between you (instead of noise, Shannon called it “information entropy”) in a way that can be quantified. And the method for reducing the noise—for recovering messages that would otherwise be lost or garbled—is decryption.

Viewed through Shannon’s theory, intimate communication is a cryptologic process. When you fall in love, you develop a compact encoding to share mental states more efficiently, cut noise, and bring your beloved closer. All lovers, in this light, are codebreakers. And with America going to war, the two young codebreakers at Riverbank were about to become lovers.