The Redacted Sherlock Holmes, Volume 6

by Orlando Pearson

  “And how does this compare with other German codes you have seen?”

  “German codes are normally replacement codes—so one symbol or number, or character-set as we call them, replaces a letter.”

  “And how do you decrypt them?”

  “We are aware of four different codes, three of which they have introduced in the last five years. In principle they are no more and no less complex than our own replacement codes. But the Germans are obviously not devotees of your monograph on codes as their use of them breaches fundamental rules of code security.”

  “Perhaps you would explain.”

  “They use codes to send messages which need not be coded whereas you said that messages should only be coded if their security is paramount. Thus, we broke one code because we noted a large amount of telegraph traffic at the end of January last year with messages ending with an exclamation mark. We soon worked out that messages were being sent to mark the Kaiser’s birthday on the 27th of January.”

  “Anything else?”

  “They take no steps to conceal the use of the letter ‘e’—much the most common letter in English, French, German, and Italian. You used that flaw in the code employed in The Dancing Men to decipher messages sent by Abe Slaney to the woman he was seeking to woo, and we have done the same to their codes. So, as you identified that a man with his arms raised must represent the letter ‘E’ as it appeared twice in a short message addressed to the lady in the case, Elsie Cubitt, so we look out for repeated characters in messages. Once we have identified what character set represents the letter ‘e,’ we are well on the way to cracking the code.”

  “And?”

  “They ignore your dictum that the carriage of a coded message should be accorded the same security as the equivalent message in plain text. We find it easy to get hold of their messages and to replace them so that their abstraction is not noticed. We do not make the same mistakes with our own messages.”

  “Perhaps you could expand on the measures you take with you own codes.”

  “We accord coded messages the same security as if an uncoded version of the same information were being sent, we only code when essential, we frequently send messages that are written in one code and then translated into another, and it is a requirement of our codes that they use a different character or character-set to code each successive use of the letter ‘e’.”

  “You are, if I may make so bold, Mr Gregson, a model student of my work.”

  Gregson flushed with pleasure at this rare word of praise from Holmes.

  “And what do you make of this code?” asked Holmes.

  “It provides none of the clues we normally use to unlock codes, Mr Holmes. It is of only four characters and none repeat themselves. If it refers to events in Sarajevo, there is no obvious means of identifying the events or the location.”

  “Could it be a pre-arranged set of characters to trigger a particular action?”

  “That may be so Mr Holmes—indeed a message with only four character-sets could hardly be anything else—but that still leaves this code uncracked and does not tell us what action is being taken.”

  Gregson’s voice tailed off uncertainly and Asquith took over.

  “We were wondering whether your schedule would permit you to try to decipher this code, Mr Holmes.”

  Holmes looked at the message, “As you say, it is hard indeed to think what meaning it could convey in so short a span as four character-sets. All four of the sets consist of three numbers ranging in size from 239 to 932. This means that multiple numbers may in a future coded message reflect the same letter. This will make decryption far harder than would normally be the case.”

  There was another long pause.

  Holmes straightened up, and I could see from his face that he had no solution.

  “Gentlemen, I cannot reason without material. I fear I am unable to give you any suggestions on the text you have given me save to say that it must be of major import if the Germans should choose this day of all days to introduce a new code. I would bid you to bring me any new messages of this three-number character-set type, but on the data that you have given to me this evening, I am not in a position to offer any solutions at this time.”

  The mood among the four of us was sombre indeed. Asquith rose to leave, and Gregson followed him. Holmes and I walked our visitors to the door, and Asquith had already gone from the step down onto the street when an insight seemed to strike him, and he turned back.

  “Mr Holmes,” he said, “you have a completely free hand to solve this matter.”

  “Prime Minister, I fear that there are other matters on which I am working on, which you know about,” said Holmes, ruefully stroking his goatee beard, “which will preclude me dedicating any significant time to decrypting this code.”

  There was a pause and I could see that the Prime Minister was wrestling with a dilemma.

  “I would reiterate what I just said,” he replied at last. “You have carte blanche. Do whatever you may wish to do and use any resources you see fit to use to crack this code. And you may, Mr Holmes,” he continued, “be candid to Dr Watson and Mr Gregson about your work for British Intelligence. Dr Watson is known from all his previous work to be trustworthy, and it is conceivable we may need him as a witness in a trial at some point. And for your investigation into this new code you may need to avail yourself of the help of Mr Gregson here, and I can hardly expect him to do your bidding if he is not informed of your other activities. I must return to Downing Street. I cannot be absent from my post for any significant length of time at this country’s moment of peril.”

  After the Prime Minister had departed, at Holmes’s suggestion Gregson came back into the house, and my friend told him and me about his counter espionage work under the alias of Altamont with the German spymaster, Count von Bork. “I pose as a disaffected Irish-American,” he said, “to give false information about British military preparedness and dispositions. And I have unmasked German spies in the highest British political and military circles.” He puffed out smoke from his pipe as he so often did in his moments of triumph. “My work is entering its critical phase, and I cannot spare time for an investigation into enemy coded messages which would require my skills to be used for interception of messages as well for their decryption. Thus, Gregson, I would ask you to use your resources to track down messages in this new code, but I will make myself available, as far as I can, if you want any help in cracking them.”

  After Gregson’s eventual departure, Holmes and I remained up late. He sat hunched over the piece of paper and addressed no word to me as he stared down. I puffed my pipe until half-past eleven. As I went to sleep, I could still hear Holmes pacing his room across the corridor.

  It was at half-past four in the morning when I heard a furious pounding at the front-door.

  I went down to open it, and Gregson burst past me into the hallway. He stood at the foot of the stairs, I suspect unsure whether to go up, but Holmes came straight down. I saw he had not rested for he was wearing the same clothes as he had the previous evening.

  “I have a new message,” gasped Gregson. “We intercepted a diplomatic bag on its way to the German Embassy in Carlton Gardens. I had no means of transport from Gower Street where my office is, so I ran all the way from there. Here it is.”

  He handed Holmes a piece of paper and, looking over his shoulder, I could see the following:

  “311, 697, 164, 197”

  “We let the original go on,” added Gregson, still out of breath, “but we took this transcript.”

  Holmes, Gregson, and I went into my study, and Holmes sat at my desk hunched over the latest message.

  “None of the same character-sets as in the first message,” I heard him mutter, “but the same number of sets. So still only four of them.”

  “Could it be a kiss
?” asked Gregson.

  Gregson saw my blank expression and explained. “A kiss, a term I learnt from Mr Holmes’s monograph, is a re-encrypted message—so a message is written in one code and then re-translated into another, as I referred to last night. I only suggest it because, as Mr Holmes says, both messages are the same length.”

  “I cannot exclude that possibility,” said Holmes, “but that merely multiplies our problems as, if what you suggest is true, it means that the Germans have not one but two previously unknown codes in this same three character-set format which contain what must be significant information, and which we have no idea of how to solve. Gregson, I fear I cannot make bricks without straw. I cannot work on this code or codes without more material.”

  Holmes continued to sit at my desk after Gregson had gone. Eventually he asked me for a piece of paper and wrote a note in longhand which he slipped into his pocket before he spoke to me again.

  “I shall have to go to see the Prime Minister, good Watson. What say you to an early morning trip to Downing Street?”

  We got the first underground train of the morning and were in Westminster soon after six o’clock. I wonder how many people there might be for whom the Prime Minister might rise at that hour, but Mr Asquith saw us soon after we arrived.

  “What can I do for you, Mr Holmes?” he asked.

  Holmes told the prime minister about the latest coded message, and then continued. “We are faced, Prime Minister, with at least one new German code and a precarious international situation. One way to break a code, is to create an event which the enemy refers to in a coded message. Knowing what the Germans might be writing about, may make it easier to crack the code that it is in—rather as Gregson was able to crack a code by deducing that the message was about the birthday of the Kaiser. Equally the bombardment of a harbour-town is likely to result in a coded message about that town, and identification of the town in the message will greatly facilitate the code-makers job in breaking the rest of the code.”

  “What you propose makes sense,” responded Asquith cautiously, “but could you be more specific. I cannot authorise the bombardment of German territory just because of the events in Sarajevo yesterday and the discovery of messages in a previously unknown code.”

  “Under my nom de guerre, Altamont, I am held in some esteem in German circles. Why do we not plant a story in the press about the success that British Intelligence has had in rounding up British traitors. It could hint that my position is in danger, and that might provoke the Germans into writing a coded message with my name in it. Altamont lends itself well to such a ruse, as it uses the letter “A” twice and the letter “T” twice and it should be easy to spot the replacement character-set used in a substitution code.”

  “How would you like this hint to be planted?”

  “I took the liberty of drafting an article, which could appear in one of the national newspapers under the by-line ‘From a Special Correspondent’.”

  Holmes handed the Prime Minister the note he had drafted at my desk and I repeat it below.

  “As a measure of the trust placed in this newspaper by the government, our Special Correspondent has been exclusively briefed by sources close to the Prime Minister, Mr Asquith. The government, according to this source, will be placing additional emphasis on rounding up the members of the spy network of the Central Powers based in this country. The source said, ‘These people pose a profound menace to our country’s interests. We have already arrested two called James and Hollis, and they have been given the treatment reserved for traitors. But we are after much bigger fish. We are aware that disaffected Irishmen in the United States have been a fecund source of traitors for the Central powers. We will root them out one by one and when we capture them, they can expect the same treatment.’”

  “To ensure that this article generates a message by the Germans,” said Holmes, “it would be as well if it appeared in a newspaper that is only published in London. The press,” he added, “is useful when you know how to use it.”

  “Thank you, Mr Holmes. I shall make sure this story is published by the end of the week.”

  “And, Prime Minister, I would ask you to use your network of spies in Germany to watch German troop movements carefully. Knowing where such movements are taking place may also be of assistance in cracking this code.”

  “Your point is clear Mr Holmes, but do not underestimate the difficulties of observing troop movements in a territory the size of the German Empire with borders adjoining Russia, the Austro-Hungarian Empire, Switzerland, the Low Countries, Denmark, and France.”

  The article Holmes had drafted was in The London Evening Standard on Tuesday the 30th of June. As the first edition of that organ is published at eleven o’clock in the morning, I was not surprised when I received a telegram from Holmes that afternoon with the message “Gregson wants to see me again. Will be with you at six.”

  Holmes was at my door at slightly before the appointed hour and, insofar as he is ever forthcoming on anything, he looked confident of success. “In code-breaking circles, what we have done is known as fishing,” he said. “The article is the bait and the Germans seem to have risen to it.”

  “What makes you so sure that they have responded to the article?”

  “Let us wait and see what Gregson brings us—although I cannot believe he would have asked to meet me here, if another message in this new code had not been sent—and the timing, straight after my article appeared in the Evening Standard, is very promising.”

  At six Gregson was with us, and he came straight to the point.

  “We intercepted this message on its way from the German Embassy at Carlton Terrace to Count von Bork in Harwich.”

  “My handler,” Holmes reminded us with a note of triumph in his voice. “This may be easier than we hoped for.”

  Gregson handed Holmes a piece of paper and I set out below what the three of us saw that evening:

  “316, 497, 313, 327, 839, 723, 839, 753, 583, 193, 88X”

  Holmes drew out the two other messages and put them on the table in front of him. He bent himself over the three messages, and his brow furrowed in concentration. My heart sank into my boots at the doleful look on his face when he eventually looked up.

  “I fear that even with this additional message I cannot advance.”

  He pointed at the new message and at the two ones seen previously which I set out below:

  “952, 395, 239, 523”

  “311, 697, 164, 197”

  “The new message contains only eleven character-sets. It repeats only one set within the message and does not repeat any of the other eight character-sets from the other two messages.”

  “What about the X at the end of the message?” asked a downcast Gregson. “That is something we have not seen before.”

  “I cannot,” replied Holmes thoughtfully, “account for it. It may be a normal part of the code—a total of nineteen character-sets two of which repeat still do not furnish us with much material—or it may be that a modified character-set refers to a specific place, person, or thing of special significance. But, until we find out what that place, person, or thing is, that only makes the matter harder.”

  Holmes paused and lit his pipe.

  “Do not, good Gregson, rest in your search for more messages of this type. They cannot but be hugely important but how I cannot say.”

  Gregson left, and Holmes carried on staring at the same three pieces of paper.

  “Consider this, good Watson,” he said at last, “the Germans are only using this new code very exceptionally. My handler is von Bork. And the Germans regard my activities as of supreme importance. You have to ask yourself what else the embassy in London might be writing to von Bork about. And yet they confine the message to eleven character-sets.”

  “What if we work on the assumption that
one of the character sets refers to you under your alias?”

  “That is of course a possible hypothesis. But let us say that they wish to say something like ‘Altamont in danger’ which would be ‘Altamont in Gefahr’ in German. The remaining character sets would provide ten letters, and within these and the eight character-sets from the other two messages, you would think we would have more than one letter repeated within the message or from one of the other messages. You try to construct a meaningful text with eighteen letters only one of which repeats. It is an impossible task.”

  “Could more of the character-sets represent words?”

  “What you suggest would explain the mysteries of these short texts but would also multiply our problems as we would be faced with a character-set for most words. Basic Japanese has pictograms reflecting whole words. It requires the reader to know a minimum of two-thousand pictograms. You may imagine the difficulties of decrypting a code that has a character-sets that represent whole words in any significant number.”

  He tamped down the tobacco in his pipe before continuing.

  “And you should also consider the impracticality of devising a code with thousands of character-sets that is only used in the rarest of cases. It is hard for the sender of the message to encode and hard for the recipient of the message to decrypt. We must hope for more instances of this code being used.”

  “I am at a loss.”

  “So, I fear, am I.”

  And there the matter rested.

  July rolled on. The weather was beautiful, and the events got ever more menacing. By 1 August Germany had declared war on Russia and, on that day, I was called to Downing Street. Sitting alongside the Prime Minister was the foreign secretary, Mr Edward Grey, who gave us a brief summary of events and plans.

  “With the Germans and the Russians at war, it is hard to see how we and the French can stay out of it. The lights are going out all over Europe. I do not know that we will see them relit in our lifetimes. Almost every country in Europe is mobilising its troops as each plans how to launch invasions, thwart invasions, or to defend its neutrality.”