by Kahn, David
Habenicht let go the anchors and their chains. He had the drinking and washing water pumped out. Ash ejectors flung coal into the sea. All but sixty boxes of munitions were dumped over the side. All movable steel parts—the minelaying rails, bulkhead doors, doors on the forward turrets, steel cables, coaling equipment—were pushed overboard. The Germans’ efforts were spurred by the likelihood that the officials on Odensholm, which was Russian territory with a light-house and a signal station, had alerted superior authorities at the major Russian port of Tallinn, only 50 miles away. Habenicht again ran the engines forward and backward at various speeds. The Magdeburg moved not an inch.
Habenicht worried that the cruiser’s secret documents might fall into the hands of the Russians. In addition to the charts of German minefields and the ship’s war diary, these included the main Imperial German Navy code and the cipher key used to encipher its codewords and thus provide another layer of secrecy. Bender, who was in charge of the destruction of these documents, brought the codebook that was in the steering room, together with its cipher key, to the stokehold and burned it. Sailors did the same for other secret documents. But two other codebooks—one on the bridge and one in the radio shack—as well as a cipher key were retained for communicating with rescuers and higher commands. A fourth lay hidden and apparently forgotten in a locker in Habenicht’s cabin.
As dawn approached, the seabed and the stones on which the ship was lying became visible. At 8:30, with the fog lifting, the fast and powerful German torpedo boat V-26 appeared, attached a line, and tried to pull the Magdeburg off. She failed. Habenicht decided he might as well do some damage and fired some 120 shots at the lighthouse, chipping it, and at the signal station, setting it ablaze. By then the radio shack was reporting many signals from Russian ships; apparently they were on their way. Since all attempts to free the Magdeburg had failed, Habenicht regretfully concluded that he had to blow her up instead of letting her fall undamaged into enemy hands.
Charges were set fore and aft. The crew was to get off the ship and onto the V-26, which was to come alongside. Suddenly a shout rang through the ship. “The fuses are lit!” Habenicht had not ordered this; it had been done by mistake. The vessel would blow up in only four and a half minutes! In the tumult that ensued, Bender, the first radio officer, directed the second radio officer, Lieutenant Olff, to have the codebook and the cipher key from the radio shack brought to the V-26. On Olff’s instructions, Radioman Second Class Neuhaus grabbed the codebook, and Radioman Third Class Kiehnert the cipher key papers. The bridge’s codebook was in the hands of Radioman Second Class Szillat. The first officer, unable to find Habenicht as the seconds ticked away, ordered the crew members to the afterdeck, where the V-26 was to pick them up. He called for three cheers for the kaiser, had the two ship’s boats lowered, and commanded, “All hands abandon ship!”
Upon hearing this, Szillat flung the codebook he was carrying over the side, toward the stern. It splashed into what he said was a “dark” place about 15 feet from the ship and immediately sank. Then he leaped overboard. Kiehnert, too, jumped into the water, holding the radio shack’s cipher key. He was struck by men following him, and when he came to the surface, he noticed that he had lost the key. Then, at 9:10, the forward charge detonated. It split the vessel in half, tore open the fore part from near the bow to the second smokestack, and hurled huge pieces of steel into the air. They rained down upon the scores of men who were trying to swim to the V-26. Neuhaus, who had the radio shack’s codebook, was seen in the water before the explosion but was missing later; no one knew what happened to the codebook he was carrying.
The V-26 picked up many of the swimming men, including Szillat and Kiehnert. For fear of being destroyed in the explosion of the Magdeburg’s after charge, the V-26 stayed away from the cruiser and did not rescue the men still aboard. The Russian ships, appeared and began to fire at the torpedo boat. One shell swept eight men overboard; another smashed into her starboard side, destroying the officers’ wardroom and killing all who were in it, mainly wounded men from the Magdeburg. But the V-26 got away.
Habenicht appeared briefly on the Magdeburg’s bridge when he heard the cheers for the kaiser, then vanished again into the bowels of his cruiser. Along with a few others, he awaited his fate on the ship. Bender, his little dog, and a few dozen sailors, among them Neuhaus, swam to Odensholm, where they were taken prisoner. One of the Russian ships, the torpedo boat Lejtenant Burakov, sent a boat with armed men, led by its first officer, Lieutenant Galibin, to the Magdeburg. The crew members still on board offered no resistance and were taken prisoner. Habenicht, whom Galibin thought was “a true gentleman,” offered the Russian his dagger, which Galibin courteously declined. The Germans on both the ship and the island were rowed to one of the Russian cruisers and were later sent to a prisoner-of-war camp in Siberia; on the way, the little dog Schuhmchen was taken from Bender. He was never seen again.
Galibin lowered the black, white, and red German naval war flag and raised the white czarist flag with its diagonal light blue cross. Then, revolver in hand, he searched the wreck of the Magdeburg. He found a locker in Habenicht’s cabin and broke it open. Hidden deep within it was a German codebook, forgotten by all in the excitement of the catastrophe. Galibin removed it and, together with a packet of Bender’s private letters and other documents, had it transferred to the Lejtenant Burakov, The Allies had come into possession of the key secret of the Imperial German Navy, the one that could give them access to many others.
Later, Russian divers supplemented Galibin’s find. Using strong electric lights to inspect the stony seabed up to 30 feet from the stranded vessel, they found in the clear waters the codebook that Szillat had thrown overboard and the one that Neuhaus had lost in the water.
Recognizing the value of the codebooks and cipher keys to the British, the major naval power, the Russians loyally notified their ally of their find and said that they would give the British the documents if they would send a small warship “as most secure means” of getting them and the officers accompanying them to Britain. The Russians courteously set aside for the British the undamaged code, the one found in Habenicht’s locker, which bore the serial number 151. They kept the waterlogged codes for themselves.
The task of taking codebook No. 151 to England was assigned to three naval officers, Captain Mikhail A. Bedrov, Commander Mikhail I. Smirnov, and Count Constantine Benckendorff. A cosmopolitan, mustachioed combat veteran of the Russo-Japanese War, Benckendorff was the son of the ambassador to Great Britain. He had served a year as a cipher clerk in the London Embassy. One Sunday morning in September he was on watch on the battleship Poltava in Tallinn roadstead, pacing the quarterdeck and listening to the sailors’ choir chanting the Russian Orthodox mass, when a yeoman handed him an order to report immediately to the flag captain. On the flagship he was “amazed and delighted” to be told he would be going to London.
He was given the precious codebook in St. Petersburg. It was in a satchel with a large piece of lead sewn in to make it sink in case he had to throw it overboard and with a strap to carry it over his shoulder. This bag he took with him to Archangel, where he boarded a Russian volunteer fleet steamer. The vessel was to meet H.M.S. Theseus at Alexandrovsk (now Polyarnyy), a port near Murmansk, where the aging cruiser had arrived early in September. Owing to delays and misunderstandings, the Theseus and the steamer did not sail until October 1. After an uneventful crossing over the top of Norway, punctuated only by a few vague U-boat warnings, they arrived on October 10 in Scapa Flow, the great circular basin north of Scotland that served as one of the Royal Navy’s chief bases; the Russian steamer went on alone, reaching the English port of Hull a couple of days later. After a slow night train ride, Benckendorff reached the Russian embassy at dawn. He greeted his parents, then routed out the naval attaché, and the two went, early on the morning of October 13, to the Admiralty. There, in one of the most significant moments in the long history of secret intelligence, they handed Win
ston Churchill, first lord of the Admiralty, a gift more precious than a dozen Fabergé eggs: the big, fat, blue-bound Signalbuch der Kaiserlichen Marine.
The Signalbuch went to the Admiralty’s fledgling codebreaking agency. This had come into being, quite by chance, on the day Britain entered the war. Though individuals in the British army had solved cryptograms in the Boer War and on India’s Northwest Frontier, the navy had never engaged in cryptanalysis and had made no preparations for it. But when hostilities formally commenced on August 4, 1914, radio stations of the Royal Navy, the post office, and the Marconi company began to pick up coded messages, apparently of German origin. These they forwarded to the Admiralty’s Intelligence Division. Its director, Rear Admiral H. F. Oliver, recognized their potential and knew at once who might realize it: his good friend, the director of naval education, Sir Alfred Ewing. A short, thickset Scot, given to wearing mauve shirts with white wing collars and a dark blue bow tie with white polka dots, Ewing was a distinguished engineer. He had dealt with cables in Uruguay and had, a year or so before, described a cipher mechanism to Oliver. Oliver regarded him as of “very great brain power, in fact a man who stood out among clever men.” Everyone thought naval education would not be much needed during the few months until victory was won. Oliver told Ewing he had no one to deal with the intercepts; would Ewing see if he could make anything of them? Grasping “at even the most unpromising chance of being useful,” Ewing accepted at once.
To assist him, he called on some people whose abilities would be useful and who were discreet and available: faculty members, particularly instructors in German, at the Royal Naval Colleges at Dartmouth and Osborne, which were on vacation in August. One of the first volunteers was Alastair Denniston, thirty-three, a German master at Osborne. A short, quiet Scot, he had studied at Paris and Bonn and had helped win a bronze for Great Britain in field hockey as a member of the Scottish team in the 1908 Olympics in London. Like the others, Denniston was, in his own words, “singularly ignorant of cryptography.”
He and his colleagues worked in Ewing’s cramped office. They did little more than sort and file intercepts, learn to distinguish German naval messages from military ones, and discover that call signs such as POZ and KAY, the “names” of radio stations, were not the same as the coded texts of messages. But they made not a dent on the German naval messages.
A month later, the Signalbuch from the Magdeburg arrived in Ewing’s office. But what seemed to be the answer to a cryptanalyst’s prayer did not at first turn many of the coded messages into plain German. The book consisted essentially of hundreds of pages of columns of five-digit and three-letter groups standing opposite German words:
63940 OAT Ohnmacht -ig
41 OAU Ohr, Ohren-
42 OAÜ Okkupation, Okkupations, -ieren
43 OAV Ökonomie -isch
44 OAW Oktant
45 OAX Oktober
This meant that Oktober would be encoded as OAX or 63945, and OAÜ (the Germans usually used the letters, not the numbers), would mean Okkupation or its derivatives. But attempts to reduce the intercepts to German by this straightforward method produced gibberish in most cases; the only messages that were solved were weather reports and messages to auxiliary vessels. To resolve the mystery, Ewing brought in the head of the Intelligence Division’s German Section, Fleet Paymaster Charles J. E. Rotter, who had spent many leaves in Germany. He was installed in Ewing’s secretary’s office.
A break came when the Handelsschiffsverkehrsbuch, or HVB, another maritime code, seized from a merchantman off Melbourne, Australia, arrived at Ewing’s office, along with a method for disguising the code’s four-letter codewords. The letters of the codewords were replaced with other letters given in a list, or key. For example, the codeword for Fregattenkapitän (commander) was RABL; the key specified that the substitute for R was T, for A, L, and so forth, so that RABL would actually be transmitted as TLIN. This procedure is called superencipherment.
Rotter seems to have reasoned that the Germans were using the same system to encipher the codewords of the Signalbuch, so that OAO might become, for example, JVJ. Working with a succession of messages whose serial numbers the Germans had enciphered—“Their folly was greater than our stupidity,” Alastair Denniston commented—Rotter by early November had discovered the key to the superencipherment, thus exposing the main messages of the High Seas Fleet.
This breakthrough suddenly gave the handful of cryptanalysts plenty to do. More cryptanalysts were taken on, and a new, larger workplace was found, Room 40 of the Old Building of the Admiralty. “Room 40” became the unofficial name for the codebreaking agency.
Early in December this thriving and fortunate agency got another lucky break. The third major codebook of the Imperial German Navy arrived in sodden condition in Ewing’s office. The captain of the torpedo boat S-119 had thrown it and other papers overboard in a lead -lined chest when he encountered a British squadron off a Dutch island; a month and a half later a British fishing boat hauled it up in its trawl. Soon the new codebook, the Verkehrsbuch, a five-numeral code (Kaiser = 46786) used at sea by flag officers, was drying before Ewing’s fire.
The new book too was used with a superencipherment, which was discovered the day the book arrived. Some days earlier the British had intercepted two almost identical German naval messages. One was encoded entirely in the Magdeburg codebook and so could be read by Room 40. A small part of the second was encoded in the newly found code. “It is never wise to mix your ciphers,” Ewing remarked. “Like mixing your drinks, it may lead to self-betrayal” This did. The Signalbuch gave the meaning of the coded portion of the Verkehrsbuch message; these German words could be looked up in the Verkehrsbuch to find the basic codenumbers, and comparison of those with the superenciphered codenumbers of the message revealed the formula for conversion.
Thus, before the war was four months old, Britain had gained, mainly through means other than codebreaking, the ability to read the most secret intentions of its chief enemy’s navy.
Nor did Britain’s cryptologic gifts from the sea end there. Later in the war the Germans changed their codes, but divers recovered the new ones and their superencipherments from U-boats sunk in the shallow waters around Britain. One of the most successful of these divers was Shipwright E. C. Miller, a pale, wiry young diving instructor. His most remarkable characteristic was a sangfroid in facing horrors that would have frightened off many other men. Once he investigated a German submarine sunk off the Yorkshire coast. She was lying on her side, and Miller found no point of entry. He rigged charges and blew off the top of the conning tower. As the water cleared, he saw the head of a dead German seaman rise above the ragged rim of the conning tower as if peering out. That didn’t stop Miller. In his bulky suit and spherical armored helmet, he clambered in. At once the imprisoned corpses crowded around him. He calmly tied them up with lanyards and pursued his exploration of the U-boat, stumbling through the narrow black passageway of the underwater tomb until, in a compartment aft of the officers’ quarters, he found a strongbox. This contained one of the new codes and some of its superencipherment keys.
As the war progressed and the value of codebreaking became increasingly obvious, the staff of Room 40 swelled. Ewing recruited many members from Cambridge University, where he himself had been a professor of mechanical engineering, and from that university’s King’s College, of which he had been a fellow. Curiously, more of his recruits were classicists and linguists than mathematicians and scientists. One who proved most successful was a scholar of Greek named Alfred Dillwyn Knox, called Dillwyn.
He was the second of four sons of the Anglican bishop of Manchester. At Eton he became close friends with the future economist John Maynard Keynes. At King’s he refused the homosexual advances of Lytton Strachey, the future author of Eminent Victorians, who had fallen in love with him.
“Did I tell you,” Strachey wrote of Knox, “that he has a wonderful veil of ugliness that he is able to lower at any minute over
his face? His method is, you see, to lure you on with his beauty, until at last, just as you step forward to seize a kiss, or whatever else you may want to seize, he lets down a veil, and you simply fall back disgusted. Isn’t it a horrid trick?” Witty, clever, always ready with a new limerick, Knox played first-rate bridge with unorthodox moves that more often than not succeeded. But Keynes, who followed him to King’s, said, “He has got one of the most confused brains I have ever come across.… He is quite abnormally untidy in his work and always forgets to write down the most necessary steps.”
Knox, tall, thin, light of build, with full lips and a receding forehead, was elected a fellow of King’s in 1909, and for a short time he tutored Harold Macmillan, the future prime minister. He worked with his own tutor, a classics scholar, in preparing an edition of the minor Greek dramatist Herodas, whose sketches had been discovered at Oxyrynchus in Egypt in 1889 on a roll of papyrus. The copyist of this manuscript, Knox wrote, was “constantly puzzled by the form of the letters which he was copying,” was “prone to all the common errors of copyists,” and made “stupid alterations.” Knox and his tutor had to determine the correct meanings. The intense analysis and detailed reconstructions required by this kind of study are also needed in cryptanalysis, and when Knox was recruited for Room 40 early in 1915 at age thirty-one, he found codebreaking congenial.
He was followed to Room 40 by a younger friend from King’s, Frank Birch. Birch was seen as “a many-sided human being—a rather dull historian, an acceptable drinking companion, a mysterious private personality, a brilliant talker and a born actor. In his impersonations, as in those of all great comedians, there was a frightening element.” One of his best was of a classics tutor, who had only one eye and one hand; in Birch’s pantomime, he took himself apart so thoroughly in his room each night that nothing was left of him at all. Birch, an Etonian and a keen yachtsman, had served at sea during the first part of the war. He and Knox shared a house at 14 Edith Grove in the Chelsea section of London, where Birch gave weekly musical parties; Knox chose those occasions to work all night at Room 40. Birch excelled less in codebreaking than in collating and explaining the results.