Joe Desch was working to perfect the first two experimental prototypes, called Adam and Eve. He was under terrible pressure. Commander Ralph Meader was a taskmaster who used guilt as a motivator, and he was always telling Desch to hurry up, hurry up, that he’d be responsible for the deaths of countless more boys, more sailors and merchant seamen, if he didn’t come through with a high-speed bombe—and soon. Meader would tell the bombe designers that the U.S. Navy would have lost the Battle of the Coral Sea if they’d been the ones on that code-breaking team.
It wasn’t just a matter of getting the math to work; it was a matter of getting the machinery to run. The bulky bombes, which stood seven feet tall and ten feet long and weighed more than two tons, had hundreds of moving parts, and even a bit of copper dust could foul the works. “The design of the Bombe eventually required material and components from some 12,000 different suppliers,” noted one memo. Some components did not exist on the commercial market and had to be designed and made. The designers needed diodes, miniature gas tubes, high-speed commutators, and the carbon brushes the wheels would come into contact with. As the women in Building 26 wired commutators, the staff in NCR’s Electrical Research unit swelled from seventeen in August 1942 to eight hundred in May 1943, building the machines and perfecting the design.
In the Navy, a newly launched and commissioned warship makes a “shakedown cruise” to work out the kinks and get ship and crew running smoothly. The bombe’s shakedown cruise commenced in May 1943, around the time Louise Pearsall arrived. It was her team’s job to troubleshoot, together with Desch and Howard and some of the men who built the bombe. “The first two experimental bombes were under preliminary tests,” noted a daily log for May 3, 1943, showing the many things that could—and did—go wrong: “Encountered some incorrect wiring and shorting of the wheel segments by small copper particles” was one of innumerable entries recording snafus.
It soon turned hot and humid in Dayton, a midwestern river town, but fortunately Building 26 was air-conditioned. Even so, the unit worked in a fever. Louise Pearsall’s team, which worked apart from the WAVES wiring the wheels, would make up a menu, set the commutators, then start the bombe going, the wheels spinning to see whether the menu produced a “hit,” meaning that the permutation they’d entered into the machine could plausibly represent that day’s key setting. They would test the hit on an M-9, a small machine that replicated an Enigma. The M-9 had four rotating wheels, just like Enigma. The team would feed a message in and see if it produced German. If so, they had hit the jackpot: Their permutation represented the key setting. “It was fun,” Louise later said. “Because I was working for all these engineers and mathematicians.”
Louise got one of the first jackpots. She came up with a menu that produced a hit, and when they sent the results to Washington, a colleague there called back and congratulated her. “You just cracked one,” they told her. Her break provided evidence that the bombes could do what they were supposed to.
By June, the bombes were working, but fitfully. More machines were brought online and had to be shaken down. The daily log shows the problems the team had to cope with. On June 29, both Adam and Eve needed repair. There was “one bad red commutator”; Adam needed oil; “a short was present at the end of the run but disappeared during the test.” On July 1, “Adam blew relay”; “Eve has become temperamental”; “now we are completely shut down while maintenance is finishing both machines.” An hour later Eve was back in operation. Two hours later “Adam finally fixed.” Forty-five minutes later “Eve is out again.” And so on. On July 13 Eve was “out due to broken brushes.” Two days later, brushes on the timers “had become so soaked with oil that they were continually causing shorts.” Diodes and relays gave problems. So did things called pigtails. Another day, “Eve’s troubles were conclusively found by Mr. Howard to be tied up with her rewinding trouble.” Meanwhile, the log noted, “Girls are getting tired and are making errors again, causing reruns.”
Louise worked herself into exhaustion. On July 6 she was able to take a weeklong leave and go home to Elgin, where her father “pumped the hell” out of her, as she put it, trying to get her to reveal what she was doing. She didn’t crack. He lived the rest of his life without knowing that Louise had put his two years of college tuition payments to better use than he ever could have imagined.
By September the team had put the finishing touches on the first generation of high-speed bombes. Over the summer the Navy had constructed a “laboratory building” in the Mount Vernon Seminary compound in Washington, a big multistory structure with sturdy floors of reinforced concrete. In Dayton, flatbed cars pulled up in the dark of night on the railroad spur behind Building 26, and crates were loaded aboard. Other bombes would follow, more than a hundred in all, in the weeks that followed. NCR also manufactured M-9s and shipped those as well. Louise Pearsall rode with one of the first shipments. The train was late leaving. Louise was sitting in her seat, wondering why they were delayed, when her boss, John Howard, sat down and confided that men had been detained who seemed to be suspicious and possibly were going to sabotage the train.
She and Howard were the only ones who knew the reason for the delay. Louise Pearsall spent the long overnight trip back to Washington sitting bolt upright in her seat.
When they arrived, the male officers went to the main Navy headquarters to check in. Louise and the other enlisted WAVES had to go to a central facility at the Navy Yard, however, where the women’s formal transfer back from Dayton was processed. The sailors at the processing station started making snide comments. “You’re from Dayton!” the men exclaimed, as if this fact was something to be ashamed of. The women were taken aback.
Louise, tired and impatient, told the sailors she and the other women needed to be processed through quickly. “We have an assignment to go back to.”