Chatham exhibit shares the story of Nazi Germany’s Enigma Machines—and the Cape Codders who intercepted their messages and helped win the war!

Photo Courtesy of: Chatham Marconi Maritime Center

Submarine Rock lurks a stone’s throw off the southern coast of Sampson’s Island in my hometown of Cotuit. At high tide, the rock dives beneath the waves, an unmarked navigational hazard I often worry will sink our boat when we’re out sailing or fishing. But the rock surfaces when the waters ebb, and it looks so like a submarine’s conning tower, that some pranksters back in my father’s youth infamously swam out and painted the rock battleship gray. I’ve always chuckled at that story; how shocked folks on Cotuit’s Loop Beach and Sampson’s Island must have been when they saw what appeared to be a U-boat nearly on their doorstep! It was not until recently, however, that I came to realize the Cape has an important history of fighting real submarines . . .

On the front lines of Allied efforts to defeat Nazi Germany in World War II, code-breakers at Chatham’s Marconi Station played a critical role in the Battle of the Atlantic, helping to locate and sink many German U-boat submarines that threatened America’s coastline. In conjunction with Allied stations like Government Code and Cipher School at Blechley Park in England, service men and women in Chatham helped break the Enigma codes—encrypted messages on a diabolically intricate machine that German Admiral Karl Doenitz used to communicate with his submarine fleet. The race to decipher these codes was the subject of 2014’s popular Oscar-nominated film, The Imitation Game, and these technological breakthroughs not only hastened the Allies’ victory in the Atlantic, but the machine used to crack the Enigma codes, known as the Turing Bombe, helped pave the way for the emergence of the computer. According to a special program broadcast by the BBC, “it has been claimed that as a result of the information gained through [the Turing Bombe], hostilities between Germany and the Allied forces were curtailed by two years.” On Saturday, June 20, the Chatham Marconi Maritime Center, as it is now called, unveils a new exhibit featuring a genuine, German Enigma machine. The exhibit coincides with Chatham History Weekend (June 20-21) and is also meant to commemorate the 70th anniversary of the ending of World War II.

Photo Courtesy of: Chatham Marconi Maritime Center

The Chatham Marconi Maritime Center occupies a 13-acre site on Ryder’s Cove, near Pleasant Bay. The center includes two main buildings: an educational center and the Marconi-RCA Wireless Museum. While the educational center will hold classes this summer on technology and coding, including hands-on practice with model Enigma simulators, the actual Enigma machine will be on display in the museum, along with permanent exhibits that chronicle the history of the Marconi Station. At the station, visitors can see where local men and women intercepted German codes and helped bring the war to an end.

At the Marconi station more than 300 sailors, including units of WAVES (Women Assigned for Voluntary Emergency Service), who arrived in 1944, intercepted the Germans’ messages. Using teletype machines—electro-mechanical typewriters for transmitting messages from station to station over wires—the sailors sent the information to naval intelligence headquarters in Washington, DC, where it was decoded.

“The only thing that ever really frightened me during the war was the U-boat peril.”– Winston Churchill

Photo by: Josh Shortsleeve

“Enigma” is the name of the “electro-mechanical rotor cipher machines” built for the German military, beginning at the end of World War I. The machines are about the size of small, portable typewriters. Housed in wooden boxes, they open to reveal a keyboard, a “lamp-board” of letters, and a group of rotors that the German operators would set anew every day. Each German U-boat carried an Enigma machine, and operators would copy down incoming messages as the machine’s letters lit up.

The Chatham exhibit features a three-rotor Enigma machine, a genuine artifact built in 1937. Richard Kraycir, executive director of the Marconi center, recently demonstrated how the machine works. First, he described the machine in its historical context.

Though the Germans built more than 200,000 of the machines, only about 200 survived the war, Kraycir said. Many of the others are at the bottom of the sea. “This one,” Kraycir says, “is worth more than what I paid for my house.” The codes sent and received by Enigma machines are permutations of symbols, or an ordered combination of letters and numbers. According to Kraycir, the challenge involved in breaking the Enigma codes was that the Enigma Machine offered “156 million million permutations.” Without a way of breaking the codes, the odds of deciphering a message were akin to those of winning today’s Powerball jackpot.

The key to using the machine for communication, Kraycir added, is how its rotors are set. Each day, the German Navy would assign different rotors—in different starting positions. Once they set the rotors, the operators would close the cover of the machine and type. Kraycir demonstrated how the machine worked, showing that when he struck the “A” key, a corresponding light came on: the letter “P”. “Now watch what happens,” Kraycir said, “when I type “A” a second time.” This time, a “W” lit up.

On the receiving end of the message, an operator—with another Enigma machine set exactly the same way—would write down the letters that had been illuminated and then punch them into his own machine to decode the message. Kraycir explained that new Enigma codes had to be broken each and every day because the Germans would reset the rotors on the machines each morning.

The machine did have its limitations. For example, Kraycir said, “if you knew a word, you used that to help crack the daily code because the same letter would never come out as itself.” The online magazine, The Guardian, further explained this flaw, stating: “no letter would ever be encoded as itself. With that knowledge, as well as an educated guess at what might be encrypted in some of the messages—common phrases included Keine besonderen Ereignisse, or ‘nothing to report’ and An die Gruppe, or ‘to the group’—it was possible to eliminate thousands of potential rotor positions.”

Photo Courtesy of: Chatham Marconi Maritime Center

The Enigma machine also has connections to a permanent exhibit at the Marconi-RCA Wireless Museum entitled, “The Navy Years: World War II.” One feature of this collection is a short 2011 film by Cape Codders Ed Fouhy and Christopher Seufert, Chatham Goes To War. “Chatham, during World War II, was a hotbed of activity for a small town,” Fouhy states in a video on the museum’s website. Fouhy began his research in 2010 and discovered that scant information is available to the public about operations that took place at that time in Chatham because, “it was a very, very secret installation.”

“Doenitz was in contact with his submarines constantly,” Fouhy says on the video. “The submarines would surface at night, which was the only time their radios would operate, of course, and then they would receive their orders, or they would report back to Admiral Doenitz. Little did they know—and Admiral Doenitz didn’t realize it until years later, after the war ended—that every transmission was being read by the Allies. Many of the transmissions were monitored here in Chatham.”

Photo Courtesy of: Chatham Marconi Maritime Center

In addition to recording the Enigma codes, the Marconi station was a crucial player in the actual sinking of many U-boats. “Direction finders,” Fouhy explains, “were alerted by Chatham, which controlled a network of stations along the Atlantic coasts of both Africa and America. A compass bearing to a submarine on the surface, using its radio, was first calculated. When two or more stations heard the same signal, they could plot the location of the U-boat, so commanders could send ships and planes to attack it.” The Battle of the Atlantic, Fouhy concludes, “took the lives of over 30,000 seamen on both sides and lasted for six years.”

In a letter written to President Franklin Roosevelt, British leader Winston Churchill famously wrote, “The only thing that ever really frightened me during the war was the U-boat peril.” It’s amazing to learn that the small town of Chatham played such an integral part in laying Churchill’s fears to rest. This summer, visitors to the Chatham Marconi Maritime Center will have the opportunity to see a real piece of history in this small station that did so much to preserve America’s freedom.

Learn more about the exhibit and the center at chathammarconi.org, or call 508-945-8889.