C
QMKTXYN T
H
QMQE
KSOTEET
"Why, it is but gibberish," I said instinctively, but my words had a hollow ring as I said them. Selkirk would not have indulged in anything meaningless. I viewed the three lines of letters with narrowed eyes and tried to apply some reason to the riddle.
"Holmes, do the C and H have any significance?"
"Obviously separated from the body of the message for some reason. Selkirk expected me to solve this cipher. Therefore, it is not keyed to a prearranged text."
I was completely at sea at this point but, fortunately, Holmes explained his reasoning.
"As an instance, Q being the seventeeth letter in the alphabet and the first letter of the cipher might refer to the seventeenth word on the first page of a well-known novel. Or not so well-known for that matter. N being the thirteenth letter could refer to the thirteenth word on the second page of the same book and so forth. But such a cipher is dependent on a text known by the sender and receiver, not the case in this instance. Here we have a substitution cipher, I'm sure."
His eyes devouring the message, Holmes continued as though as talking to himself. "As a simple example, a reversal of the alphabet. Instead of an A, one uses Z while B becomes Y, and so forth. Usually, these are interesting little problems which intrigue the mind but seldom fatigue it. Here I sense difficulties. In the three lines of Selkirk's message, there are twenty-one letters. The letter E is by far the most commonly used in the English alphabet. But note, we have E used three times in the message. T is the next most common to our alphabet and it is used four times. In solving a substitution cipher, the basic step is to select the letter used most often and assume that it is E. The next most often used becomes T, the third A, and the fourth, O, and so on. In this case, the two most common alphabetic letters are the most-used in the body of the message. See also that Q is used three times while M and K occur twice. The other letters appear but once."
"Could not the C and H, positioned as they are, offer some clue?" I asked.
"I would think so. Give me but a moment."
Leaving Holmes deep in thought, I withdrew to the couch. Though confused myself, I had no doubt my friend would come up with something and soon. After all, he had authored a monograph on secret writings in which he analyzed 160 separate ciphers.
Suddenly, Holmes rose to his feet. "It won't do, Watson."
There was a tinge of annoyance in his voice and he crossed to the door and summoned Billy, instructing the page boy to inform the waiting messenger that we were on our way to St. Aubrey as rapidly as possible.
"There is something missing," he said, reentering our chambers. "A vital clue must be secured."
A short time later, we were on our way to St. Pancreas station where we boarded the first train stopping at the quiet hamlet of St. Aubrey. During our short journey, Holmes, to my delight, felt prompted to discuss methods.
"When one is faced with a problem, as we are, it is advantageous to divine another's thoughts. Therefore, I place myself in the late Basil Selkirk's situation. He has acquired the collector's dream, a famous gem and the right of ownership. But he has no desire to flaunt his possesion for death is imminent. He decides to leave the stone to the one who was instrumental in his finding it. To me. But how can he be sure I will get it? Advanced years tend to produce a distrust of everyone. Possibly an eccentricity of age or perhaps the fruits of long experience. He decides to send the location of the diamond in a cipher, banking that I will be able to break it."
"A fine summation of Basil Selkirk's final thoughts," I said, "but what do they suggest?"
"An association. Something in his immediate surroundings that Selkirk seized on as the key to the cipher he sent me."
A carriage awaited our arrival at St. Aubrey and it whisked us out of town and to the castle of the financier. The blond secretary greeted us with a harrassed manner and turned us over to a solemn-faced butler with instructions to assist us in any way. There was an air of secrecy everywhere and I later learned that Selkirk's death was not being revealed immediately for fear of the effect of the news on the financial markets of the world.
Holmes expressed the desire to view the room where the death had occurred and the butler, Meers, led us to Selkirk's study where he had breathed his last.
The room had a "much-used" feeling. There were well-filled bookshelves, a large teak desk, and a field-stone fireplace with an ornate mantle, also of teak. 'The walls were wood-paneled and the furniture was heavily carved, highly polished, early Victorian. On one wall were four canvases of moderate size. Holmes gazed at these oils casually and a puzzlement crept into his eyes. The butler was standing by the door, awaiting instructions and Holmes turned toward him.
"Meers?"
"Yes, Mr. Holmes, sir?"
"These four paintings, I don't seem to recognize them."
"Doubtful that you would, sir. The artist was not illustrious, but Mr. Selkirk fancied them."
The great sleuth crossed to the wall and looked at the oils closely. Attuned to his moods for so long, it seemed to me that Holmes's features sharpened and that predatory look was upon him of a sudden. Not for the first time I noted that, on occasion, my intimate friend resembled a bird of prey.
"That will be all, Meers."
"Very good, sir."
As the butler disappeared, Holmes looked at me with that twisted half-smile that I knew sprang from self-reproach.
"Oh, what a fool am I!" he said.
Holmes was never quite satisfied. When a solution was in his grasp, and from experience I knew that it was, he most frequently regretted not having arrived at it sooner. The life of a perfectionist is not an easy one.
"I had but to consider the career of Basil Selkirk," he continued. "He was infatuated with communications. His business success was based on information accurately and rapidly transmitted. How reasonable that he would fancy four paintings by Samuel Morse."
"I never heard of him."
"As an artist, I daresay you haven't. Morse was an art student in England and, later, Professor of Art at the University of the City of New York. He was an American, you see. After devoting the early part of his life to painting, he realized that fame would never be his in the world of art so he applied his energies to other things. In 1844, the first message was sent by wireless telegraphy, which he invented."
"Most interesting," I commented, "but the association with our missing diamond eludes me."
"Because I have not touched on the relevant matter. The former artist also invented a telegraphic code based on dots and dashes, which bears his name. An interesting feature of the Morse code is that eleven letters of the alphabet have opposites. As an instance, the distress signal given at sea."
"S.O.S." was my automatic response. "In Morse, the letter S consists of three dots or short sounds. The letter O is its opposite, being three dashes or longer sounds. Let me make this perfectly clear, Watson. What are the opening notes of Beethoven's Fifth Symphony?"
"Dot . . . dot . . . dot . . . daaaaah," I hummed quickly. I had not attended all those concerts at Albert Hall and elsewhere with my friend for nothing.
"You have just signaled the letter V, old fellow. Three dots followed by a dash. The opposite of V is B, by the way."