The Execution of Sherlock Holmes

by Donald Thomas

  ‘One further point, Master,’ he said, now looking up. ‘What advantage would this system have to distinguish it from any other form of code?’

  Strachan-Davidson looked surprised.

  ‘Only one, Mr. Holmes. Every other form of code, in letters or numbers, is adapted from something commonly understood in its uncoded form. It may be a word, a book, a numerical formula. However disguised or distorted, common knowledge lies behind it. In the case of Linear B, very little is known. Even that little knowledge is shared by only a handful of men throughout the world. The rest of mankind is excluded from the game, so to speak.’

  ‘Precisely,’ said Holmes quietly, ‘how many of that handful live in Oxford?’

  The Master thought for a moment.

  ‘Sir Arthur Evans, but he is in Crete. There are two of his assistants, but they are with him. There is the keeper of antiquities at the Ashmolean.’

  ‘And no others?’

  ‘Dr. Gross is not a member of the university. He was deputy keeper in the department of antiquities at the Royal Museum in Berlin. He retired and has lived in Oxford for a year or two.’

  ‘An elderly man with pince-nez who lives in Beaumont Street, I believe?’ Holmes inquired innocently.

  ‘Then you are familiar with him?’

  ‘A passing acquaintance.’ Yet those who knew Sherlock Holmes well, medical men above all, would have detected a quickening beat at the temples accompanying such a lucky shot in the dark. We took our leave presently. Holmes did not ask the Master for a pledge of confidentiality. Anyone who had been in the presence of Strachan-Davidson for any length of time would know that such a request was quite unnecessary.

  6

  By that evening, we were before our own fireside again in Baker Street, though not before Holmes had insisted upon a detour to the St. James’s Library, of which he was a member and from which he carried off that imposing volume which bears upon it the name of Sir Arthur Evans and the cryptic title Scripta Minoa.

  We had just finished our supper of ‘cold fowl and cigars, pickled onions in jars,’ as the poet has it, when Holmes filled his pipe again with the familiar black shag tobacco and crossed to his worktable. He laid a pile of blank paper and the intercepted signals on one side of his wooden chair and placed the Scripta Minoa on the other. He selected a fresh nib from the box for his Waverley pen, then sat down with a cushion behind him, as if for a prolonged study of the puzzle.

  There would be no more conversation that night. I made the best of a bad job, selecting a volume of Sir Walter Scott from the shelf and retiring to my own quarters. I do not know at what hour, if at all, he went to bed that night. He was sitting at the table next morning, the air once again as thick with smoke as a ‘London particular’ fog, Scripta Minoa at his side. There was no weariness about him but the exhilaration of the hunter at the chase.

  ‘We have them by the tail, Watson,’ he said triumphantly. ‘In the past hours, I am convinced I have learnt Minoan arithmetic from Arthur Evans’s drawings. A single vertical stroke is a one. A short horizontal dash is ten. A circle is a hundred. A dotted circle is a thousand. A circle with a horizontal bar is ten thousand. There are eighty-seven known syllabic signs in Linear B, but the double digits of the good Dr. Gross number ninety-two. There can be no doubt that those five extra double digits represent the means of counting.’

  For the next two days and a good part of their nights he worked his way through intercepted signals that had previously been meaningless strings of double digits. Most of them remained so. Yet here and there he swore he was able to decipher numbers in the messages. Our sitting room bristled with his gasps of frustration and self-reproach as he failed to reclaim anything more. Elsewhere, sets of numerals were repeated, but it was not yet clear what they meant. It was on the afternoon of the second day that he thumped the table with his fist and uttered a loud cry.

  ‘Eureka! I believe we have it!’

  Even now he could not decode the alphabet or syllables represented by the double digits of Dr. Gross’s cipher. Yet on the previous day he had identified five separate double digits as the Mycenean system of counting. That was all he needed. In the scanning of the present document he had decoded sequences of such numbers, though the letters of the alphabet and all its words still eluded him. The numbers he had decoded began with the sequence, 685, 3335, 5660, 120 … Even though the adjacent words remained a mystery, these numbers struck a chord in the formidable memory of Sherlock Holmes. He had encountered them before, in one of the Admiralty plans.

  He unlocked a drawer in the table and took out a thick folder containing a sheaf of papers entrusted to him by Sir John Fisher. These were copies of Admiralty documents. Holmes had requested them as being the most likely to attract our antagonists. Already, he had spent more than a day and a night working on these copies. Now a needle glimmered somewhere in the haystack.

  We worked together. Holmes read out sequences of figures from the naval documents and I checked them silently from a list of numbers he had drawn up as he had worked on the German signals over the past few days. After more than two hours, none of the numerical sequences in the signals had matched any in the Admiralty papers. I lost count of our failures as we came to yet another paper. Still the double digits that stood for an alphabet in the German code meant nothing. Only the ancient system of counting, which Holmes had deciphered after several days’ study, might help us.

  He read out a sequence of almost fifty numbers from the present document. As I checked them against the list he had made from the code, I held my breath. We read again to check for errors, and, I confess, my hand holding the paper trembled. There was no mistake. Call it luck, but from first to last, every number in the coded signal matched its equivalent number in the Admiralty document. It was soon evident that this entire coded paper must be an exact copy. Having got the numbers, we could now read the adjacent code for the objects to which they referred. The weariness left the voice of Sherlock Holmes as he grasped the key that would unlock Dr. Gross’s enigma.

  ‘Six hundred and eighty-five! Three thousand, three hundred and thirty-five! Five thousand, six hundred and sixty! One hundred and twenty! …’

  I knew, not for the first time, that my friend had done the impossible. This was Sherlock Holmes at his best and most invincible, doing something that no other man on earth could have done. He stood with his back to the fireplace as he read out the list. When we came to the end, he sat down again and spoke as if he feared it was too good to be true.

  ‘Those numerals, Watson! Identical and in the same sequence throughout the cipher and the document! It is thousands to one against mere coincidence.’

  ‘But what is the Admiralty document you have been reading figures from?’

  ‘The design calculations for the latest and most powerful battle cruiser of all, HMS Renown. By the pricking of my thumbs, I knew they would be after information such as this!’

  He sat at the table for a moment and then turned to me again.

  ‘Look at this dockyard manifest. It is a list of weights when the battle cruiser is fully loaded. All the tonnages in the right-hand column correspond to the numerals in Henschel’s signal. An entire sequence of fifty! It must be the same document. Very well. If that column of figures is correct, then each of Henschel’s double-digit code words on the left-hand side must describe the item whose weight appears on the right. See here. We have our decoded numerals for weight on the right. They stand opposite two unknown words in Henschel’s code, the first being 46-24-47. The word in the Admiralty list at this point is “General” in “General Equipment.” Therefore 46-24-47 in Henschel’s code surely stands for “General,” in whichever language. You see?’

  I began to see but he was not to be stopped.

  ‘And here again. Against the entry for “3335 tons,” the word in the Admiralty document is “Armament.” Henschel encodes this as 25-80-13-24-59. We know that the Ashmolean Museum can put sounds to Linear B syllables. In English, t
hese five double digits must sound something like “Ar-ma-me-n-t.” Thus five of the eighty-seven syllables of the alphabet are revealed! The syllables before “5660 tons” must match “Machinery.” Before “120 tons” the numerical syllables, if one may call them that, must encode “Engineer’s Stores.”’

  By evening, ignoring the tray that Mrs. Hudson brought, Holmes had broken what secret Admiralty files still refer to as the Linear B code. Dr. Gross had not translated his ciphers into German but simply encoded whatever he received. No doubt an elderly scholar of ancient languages may quail before engineering terminology. Holmes had deciphered every numerical sign for weights, the load calculations for HMS Renown. Matching the words of each item to its known tonnage, he pieced together the German code of Dr. Gross’s ancient Mycenaean ‘alphabet.’ He found that 80-41-24-53 must stand for ‘MACHINERY,’ so that 24 stood for ‘NE.’ He confirmed it in the next line where 18-46-24-27 must be ‘ENGINEER,’ for 24 was ‘NE’ in both cases. It was the same throughout the document and, indeed, in all the other coded signals. Our enemies had never varied the basic Linear B code, so sure were they that it could never be overcome.

  By next morning Holmes had equivalents for seventy of the eighty-seven letters of the word code, as well as all the numerals. Whether the learned Dr. Gross exactly copied the symbols of King Minos five thousand years ago—or varied them to suit his masters’ purpose—Sherlock Holmes had him by the tail as surely as Theseus ever had the Minotaur.

  As if to confirm this, the next transcript to reach us from the Admiralty contained a page opening with the familiar sequence of double digits 57-09-83-62-15 || 19-80-05. I checked the pencilled note I had made at the time and found that it was identical to the opening of the cipher written on the paper that Dr. Gross had left in the stool rack of the Ashmolean Museum. This time the message had nothing to do with armaments but, rather, with the time required to gather Class A Naval reservists at Chatham and other ports of the Thames estuary, in the event of general mobilization and impending war.

  7

  Not many months after this, on a hot summer day in the far-off dusty Balkan town of Sarajevo, two bullets from the gun of a Bosnian student shot dead the Archduke Franz Ferdinand of Austria and his duchess. It was well said that the bullet that killed the heir to the throne of Austria-Hungary was a shot that echoed round the world. At the time, I confess, I could not have believed that this Balkan outrage, shocking though it was, would precipitate a war unparalleled in human history. Yet there was no longer any doubt that the blindfold war that Holmes and I waged against unseen adversaries was in earnest. Our Baker Street rooms resembled more and more a battlefield. Several times that summer, during the remaining weeks of peace, Sherlock Holmes was absent for the entire day on a visit to the Admiralty. His business was with a mysterious group of people known only as Room 40.

  In the wake of our Linear B discoveries came Superintendent Alfred Swain of the Special Branch. That branch was created at the time of the Fenian explosions in the 1880s and had originally been known as the Special Irish Branch. Before long it concerned itself with every kind of threat to the security of the nation. One afternoon, when Baker Street was a trench of white summer fog and the street lamps popped and sputtered at noon, was the first time that this Special Branch officer was our guest. The clatter of a barrel organ serenaded us from the opposite pavement with ‘Take me on the Flip-Flap, oh, dear, do,’ as coins rattled into the grinder’s cap.

  The Special Branch may consist of hard, resolute men well able to take care of themselves, yet Superintendent Swain was a tall, thin figure, neatly but plainly suited. He spoke quietly and, as he sat down, he turned an intelligent equine profile and gentle eyes toward us. Inspector Lestrade had warned us scornfully what to expect from a man who read Lord Tennyson’s Idylls of the King or Mr. Browning’s translation of the Agamemnon—or even Tait’s Recent Advances in Physical Science and Lyell’s On Geology. There had been a movement among his colleagues to get rid of Alfred Swain by posting him to the Special Branch. He was thought by his CID superiors to be ‘too clever by half.’ He certainly gave the impression of a man who would rather have come to tea to discuss the novels of Mr. George Meredith—one of Sherlock Holmes’s unaccountable enthusiasms. Holmes took to him from the start. As his grey eyes studied my friend intently, Swain picked his words carefully, almost fastidiously.

  ‘Mr. Holmes, it must be said at the outset that you have lately performed a service to your country such as few men have done for many years past. Thanks to you, we now have Dr. Gross and Herr Henschel where we want them.’

  Holmes looked alarmed.

  ‘Not under arrest, I hope? I have had Sir John Fisher’s word on that.’

  Swain shook his head.

  ‘No, sir. The First Sea Lord has kept his word. Indeed, you have given us an invaluable advantage in this. We are now reading their coded signals. But before we can take the matter further, we must identify the third member of their conspiracy, presumably at the Admiralty. When that is accomplished, we shall endeavor to turn their stratagem against them, rather than throw them into prison. Thanks to you, we have the means in our hands to save the lives of hundreds of our soldiers or sailors in the event of war, even to save our country from defeat.’

  ‘I am relieved to hear it,’ Holmes said, indifferent to such flattery.

  ‘And what have you done to identify the traitor in the Admiralty?’

  ‘Both Dr. Gross and Henschel are closely watched. From their method of procedure, it seems that Henschel probably knows nothing of the spy’s identity. It is possible that neither of them does. Henschel appears to be a mere technician who transmits whatever is given him. Each man works, as it were, in a watertight compartment. None of them, if he were caught, could betray any part of the conspiracy but his own.’

  ‘But you have connected their movements together?’

  Swain sat back in his chair and folded his hands across his waistcoat.

  ‘We have had Dr. Gross under observation. He uses no telephone. He has sent two wires, both of which we have read. They were directed to the librarian at the British Museum, requesting certain books to be brought up from the stacks for Dr. Gross’s visit. He also receives a small amount of post, three communications in the past five weeks.’

  ‘You have opened those envelopes, Mr. Swain?’

  ‘We are aware of their contents, sir,’ said Swain evasively. ‘Apart from Henschel and Dr. Gross, there is the man whom I will call the naval spy. There appear to be twenty-four people at the Admiralty, from senior officers to junior clerks, who might have taken the design calculations of HMS Renown from the building in order to copy them. We have had them all under observation for some weeks and they have made no evident contact with either Dr. Gross or Mr. Henschel. Yet during that time, in the present international tension, the coded German signals have been transmitted almost nightly. We do not believe that Henschel can be transmitting from his rooms. Yet the signals are going out from somewhere near Sheerness, no doubt to a German naval vessel or trawler in the North Sea.’

  At this point Swain took a notebook from his pocket and began to read a list of the information transmitted in the past few weeks.

  ‘Particulars of Armament: Indefatigable Class. Particulars of Anti-Torpedo Boat Guns, 4-inch and 6-inch. HMS Princess Royal: replacement of nickel steel, armour diagram. Comparison of Boiler Weights and Performance in HMS Inflexible, boiler by Yarrows, Ltd., and HMS Indomitable, boiler by Babcock & Wilson. I understand, gentlemen, that Yarrow boilers are lighter and would allow Indomitable’s six-inch armor to be increased to seven inches without affecting her speed.’

  Alfred Swain paused, then added.

  ‘That is a sample of the technical information passing to our adversaries. More recently there have also been manoeuvre reports, gunnery ranges, torpedo matters, fire control, and signals. Last week, for the first time, there were answers to questions that Henschel must have received. Which parts of the fleet hav
e been in the Firth of Forth since the beginning of May—the First and Eighth Destroyer Flotillas or any ships else? Have there been mobilizing tests of flotillas or coastal defences? What numbers of the Royal Fleet Reserve Class A reservists are called in for the yearly exercise?’ Swain paused and looked at us. ‘All these are details vital to the other side in any immediate preparations for war.’

  Holmes crossed to the window, drew aside the net curtain, and looked down into the thin summer fog. It was possible to see across the street, and no doubt, though the barrel organ was still rattling out its tunes, he satisfied himself that the movements of our visitor were not under observation by our enemies.

  ‘Tell me about Dr. Gross, Mr. Swain.’

  Swain looked a little uncomfortable.

  ‘There is little to tell, sir. He was an archaeologist as a younger man, with Schliemann at the discovery of Troy, and then deputy keeper of antiquities at the Royal Museum in Berlin. He has lived quietly as a retired gentleman in Beaumont Street for the past two years. He goes out either to the Ashmolean or to work in one of the libraries. He takes lunch at the Oxford Union Society, of which he is a member. That seems to be his only social contact. He retires early to his rooms until the next day. In the past five weeks he has visited London each Monday and stayed for one night at the Charing Cross Hotel. He leaves each morning after breakfast and walks up the Charing Cross Road to the British Museum.’

  ‘Who watches him?’

  ‘He works all day in the North Library, Mr. Holmes, where I have kept him company—at a distance. He speaks only to the assistants and leaves at five thirty. He dines early at an Italian café in Holborn, then walks back to the hotel by eight P.M. One of my colleagues is already dining at the café when he arrives. Dr. Gross speaks only to the waiter and returns direct to the hotel. Whoever the spy in the Admiralty may be, it seems he does not write to Dr. Gross, or speak to him, or communicate by telegram or telephone. We have watched the old man every minute, so far as we can. There appears to be no dead letter box except the hollow frame of the rack of camp stools in the Ashmolean Museum. Dr. Gross uses that only to leave the encoded messages for Henschel. It is possible that Henschel does not know the code and, though a member of the conspiracy, does not know precisely what the signals contain when he transmits them.’