The garden beyond was small and neat, with a flagged path leading to the rear steps. The windows here were all in darkness save for a faint glimmer in the basement, where the servants’ quarters must lie. Moving with great caution, Holmes descended the steps and pressed his face to the narrow pane beside the door. After a moment, he motioned me to join him holding his finger to his lips. Peering in, I saw a plainly furnished basement kitchen. A single gas jet burned low over the table, where a middle aged cook sat dozing with a book in her lap. Beside her, on the dresser, stood a tray on which rested a decanter and several wine glasses. The decanter was half full of a dark liquid. Holmes’s fingers touched my arm lightly. “Observe the colour,” he whispered in my ear. “That is not a port. More likely a heavy claret. Now note the second decanter, partly hidden by the loaf. That one contains a paler fluid. This, I suspect, is where our interest lies.” He tried the area door; it yielded noiselessly. In another instant we were inside, the warm, close air of the kitchen about us. The cook stirred but did not wake as Holmes moved to the dresser. From his pocket he drew a small glass vial and a bent quill. With the utmost delicacy, he tipped the decanter and allowed a few drops of its contents to fall into the vial. This he stopped and replaced in his pocket. Then, as silently as we had entered, we withdrew into the misty night. Back in Baker Street, Holmes went straight to his chemical table. The gas hissed softly as he set a Bunsen burner alight and began to test the pale wine we had brought. “The method is telling,” he said as he worked. “In Harrowgate’s case, the poison was introduced into his water supply, crude, perhaps, but effective for a recluse who never drinks wine. Allardice, however, is a wine merchant and a convivial soul; his guard would be down at the dinner table. And Sir Reginald, with his knowledge of good vintages, could mask the taste of almost any soluble agent.” Within twenty minutes the answer lay before us. In the glass dish a faint crystalline residue clung to the sides. “Antimony again,” Holmes pronounced. “The same poison, the same hand. The link is now absolute, Watson. Sir Reginald has attempted once, and will attempt again tomorrow evening.” “What do you propose?” I asked. “A substitution. I shall see to it that Allardice’s glass is changed at the critical moment. When Sir Reginald himself drinks the wine, the effect will be immediate. I have the antidote ready. But we must act with great discretion; the trap must be complete.” The following evening found us once more in Mayfair, though this time by the front door and in the guise of expected guests. Holmes had contrived, through a note written in Fairbrother’s hand, to secure us an invitation to dinner for ’a discussion of tontine matters.’ Allardice was there, looking pale but cheerful; Sir Reginald Poynter greeted us with every appearance of warmth. The table was handsomely laid, the courses well chosen, and the wine flowed freely. Sir Reginald presided with an air of genial authority, pressing this dish and that upon his guests. At last, as the meal drew to a close, he rose to fetch a special bottle. “A little something from my private cellar,” he announced. “A Château Margaux ’78, you will find it a rare treat.” Holmes and I exchanged a glance. The glasses were filled for each of us and Sir Reginald handed one to Allardice ,myself and Holmes with a flourish. It was at this moment that Holmes acted. With a deft movement, he leaned forward as if to examine the wine’s bouquet, and in so doing switched Allardice’s glass with Sir Reginald’s own. The Baronet, absorbed in his own performance, noticed nothing. “To absent friends,” he said to Allardice, and they both drank deeply whilst Holmes and I merely raised our glasses. Sherlock, smiling and looking at Sir Reginald Poynter, said “I switch the glasses.” The Baronets hand trembled as he set down the glass. Holmes was on his feet instantly, producing a small bottle from his pocket. “Allow me, Sir Reginald,” he said coolly, "I suggest you induce vomiting immediately and I will mix this tannic acid with plenty of tea. It will counteract the effects that you attempted to induce on Allardice here.” The baronet stared at him in mingled astonishment and fear. “What the devil?” “The devil is exactly the matter, Sir