"Exactly, my dear Watson! Hence the extreme importance of Porlock. Ledon by some rudimentary aspirations towards right, and encouraged by thejudicious stimulation of an occasional ten-pound note sent to him bydevious methods, he has once or twice given me advance informationwhich has been of value--that highest value which anticipates andprevents rather than avenges crime. I cannot doubt that, if we had thecipher, we should find that this communication is of the nature that Iindicate."
Again Holmes flattened out the paper upon his unused plate. I rose and,leaning over him, stared down at the curious inscription, which ran asfollows:
534 C2 13 127 36 31 4 17 21 41
DOUGLAS 109 293 5 37 BIRLSTONE
26 BIRLSTONE 9 47 171
"What do you make of it, Holmes?"
"It is obviously an attempt to convey secret information."
"But what is the use of a cipher message without the cipher?"
"In this instance, none at all."
"Why do you say 'in this instance'?"
"Because there are many ciphers which I would read as easily as I dothe apocrypha of the agony column: such crude devices amuse theintelligence without fatiguing it. But this is different. It is clearlya reference to the words in a page of some book. Until I am told whichpage and which book I am powerless."
"But why 'Douglas' and 'Birlstone'?"
"Clearly because those are words which were not contained in the pagein question."
"Then why has he not indicated the book?"
"Your native shrewdness, my dear Watson, that innate cunning which isthe delight of your friends, would surely prevent you from inclosingcipher and message in the same envelope. Should it miscarry, you areundone. As it is, both have to go wrong before any harm comes from it.Our second post is now overdue, and I shall be surprised if it does notbring us either a further letter of explanation, or, as is moreprobable, the very volume to which these figures refer."
Holmes's calculation was fulfilled within a very few minutes by theappearance of Billy, the page, with the very letter which we wereexpecting.
"The same writing," remarked Holmes, as he opened the envelope, "andactually signed," he added in an exultant voice as he unfolded theepistle. "Come, we are getting on, Watson." His brow clouded, however,as he glanced over the contents.
"Dear me, this is very disappointing! I fear, Watson, that all ourexpectations come to nothing. I trust that the man Porlock will come tono harm.
"DEAR MR. HOLMES [he says]:
"I will go no further in this matter. It is too dangerous--he suspects me. I can see that he suspects me. He came to me quite unexpectedly after I had actually addressed this envelope with the intention of sending you the key to the cipher. I was able to cover it up. If he had seen it, it would have gone hard with me. But I read suspicion in his eyes. Please burn the cipher message, which can now be of no use to you.
FRED PORLOCK."
Holmes sat for some little time twisting this letter between hisfingers, and frowning, as he stared into the fire.
"After all," he said at last, "there may be nothing in it. It may beonly his guilty conscience. Knowing himself to be a traitor, he mayhave read the accusation in the other's eyes."
"The other being, I presume, Professor Moriarty."
"No less! When any of that party talk about 'He' you know whom theymean. There is one predominant 'He' for all of them."
"But what can he do?"
"Hum! That's a large question. When you have one of the first brains ofEurope up against you, and all the powers of darkness at his back,there are infinite possibilities. Anyhow, Friend Porlock is evidentlyscared out of his senses--
kindly compare the writing in the note tothat upon its envelope; which was done, he tells us, before thisill-omened visit. The one is clear and firm. The other hardly legible."
"Why did he write at all? Why did he not simply drop it?"
"Because he feared I would make some inquiry after him in that case,and possibly bring trouble on him."