‘You are a collector of seal rings and coins from the ancient world, I believe.’
Strachan-Davidson turned round with the kettle in his hand, beaming at us.
‘You have heard of my winter journeys to the Middle East, I imagine. A numismatist in a dahabeeah, as my young men call me here, a coin collector in an Egyptian sailing boat. I have one or two seal rings. You may still pick them up from market stalls in Cairo and in western Crete, you know.’
‘And Linear B?’
‘I have followed the work of Sir Arthur Evans with great interest. A good many of the texts were published lately in his book
Scripta Minoa
. Unfortunately he is still in Crete, so you cannot very well consult him.’
Holmes nodded.
‘The question is a simple one, Master. Could Linear B be used as the basis of a code? I beg you to consider the question most carefully.’
The Master’s ample eyebrows rose once more.
‘Oh yes, indeed. Linear B
is
a code, Mr. Holmes. Nothing else. It is a code so remarkable that no one has yet resolved it. A few decipherments here and there but very few and amounting to very little. Much of the rest of our understanding is guesswork. A school of thought, to which I am inclined to belong, believes these symbols to be early forms of classical Greek. From that there has been an attempt to evolve pronunciation. There is far to go.’
‘Deciphered or not, its structure might form a modern naval or military code?’
The Master handed us tea in silence.
‘The subject matter is the palace of Knossos, particularly its ships and arsenal. However, to draw each pictogram would be laborious. Nor could you print them, for no printer’s type would be available.’
‘How do scholars make texts available to each other? I imagine that must often happen.’
‘Indeed, Mr. Holmes. The problem has been solved by certain scholars in Etruscan and Babylonian by reducing ancient symbols to modern numerals. Each symbol is given a number, as a kind of shorthand.’
‘Could each Linear B symbol be a letter of an alphabet expressed as a number?’
The Master shook his head.
‘No, Mr. Holmes. It is early days but, it seems, each symbol is a syllable rather than a single letter.’
Sherlock Holmes let out the long sigh of a man who is vindicated after all.
‘Thus,’ Strachan-Davidson continued, ‘a modern message in Linear B would consist of several double digit numbers in groups, each double digit representing a syllable or whatever unit the code-maker chose and each group making up a word. It could serve for whatever message you wished to send. You would not have to decipher Linear B to use its signs as such a form of communication, though you might choose to do so.’
Holmes was in his familiar attitude, listening with eyes closed and fingertips pressed together.
‘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.
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, these 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.
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.