THE LAST LINK
before I had placed my little case on the table near the window, and the table, tilting up, had deposited it upon the floor on precisely the identical spot. In exactly the same way, Mrs. Inglethorp had laid down her cup of coffee on reaching her room the night before, and the treacherous table had played her the same trick.
"What happened next is mere guess work on my part, but I should say that Mrs. Inglethorp picked up the broken cup and placed it on the table by the bed. Feeling in need of a stimulant of some kind, she heated up her coco, and drank it off then and there. Now we are faced with a new problem. We know the coco contained no strychnine. The coffee was never drunk. Yet the strychnine must have been administered between seven and nine o'clock that evening. What third medium was there—a medium so suitable for disguising the taste of strychnine that it is extraordinary no one has thought of it?" Poirot looked round the room, and then answered himself impressively. "Her medicine!"
"Do you mean that the murderer introduced the strychnine into her tonic?" I cried.
"There was no need to introduce it. It was already there—in the mixture. The strychnine that killed Mrs. Inglethorp was the identical strychnine prescribed by Dr. Wilkins. To make that clear to you, I will read you an extract from
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