appeared, however. The dog continued to lie stretched upon the cushion, breathing in a laboured way, but apparently neither the better nor the worse for its draught.
Holmes had taken out his watch, and as minute followed minute without result, an expression of the utmost chagrin and disappointment appeared upon his features. He gnawed his lip, drummed his fingers upon the table, and showed every other symptom of acute impatience. So great was his emotion that I felt sincerely sorry for him, while the two detectives smiled derisively, by no means displeased at this check which he had met.
"It can't be a coincidence," he cried, at last springing from his chair and pacing wildly up and down the room; "it is impossible that it should be a mere coincidence. The very pills which I suspected in the case of Drebber are actually found after the death of Stangerson. And yet they are inert. What can it mean? Surely my whole chain of reasoning cannot have been false. It is impossible! And yet this wretched dog is none the worse. Ah, I have it! I have it!" With a perfect shriek of delight he rushed to the box, cut the other pill in two, dissolved it, added milk, and presented it to the terrier. The unfortunate creature's tongue seemed hardly to have been moistened in it before it gave a convulsive shiver in every limb, and lay as rigid and lifeless as if it had been struck by lightning.
Sherlock Holmes drew a long breath, and wiped the perspiration from his forehead. "I should have more faith," he said; "I ought to know by this time that when a fact appears to be opposed to a long train of deductions, it invariably proves to be capable of bearing some other interpretation. Of the two pills in that box, one was of the most deadly poison, and the other was entirely harmless. I ought to have known that before ever I saw the box at all."
This last statement appeared to me to be so startling that I could hardly believe that he was in his sober senses. There was the dead dog, however, to prove that his conjecture had been correct. It seemed to me that the mists in my own mind were gradually clearing away, and I began to have a dim, vague perception of the truth.
"All this seems strange to you," continued Holmes, "because you failed at the beginning of the inquiry to grasp the importance of the single real clue which was presented to you. I had the good fortune to seize upon that, and everything which has occurred since then has served to confirm my original supposition, and, indeed, was the logical sequence of it. Hence things which have perplexed you and made the case more obscure have served to enlighten me and strengthen my conclusions. It is a mistake to confound strangeness with mystery. The most commonplace crime is often the most mysterious, because it presents no new or special features from which deductions may be drawn. This murder would have been infinitely more difficult to unravel had the body of the victim been simply found