POIROT PAYS HIS DEBTS
"Oh, Lawrence! No, I don't think so. He's always a nervous chap."
"His suggestion that his mother might have been poisoned accidentally by means of the tonic she was taking, that did not strike you as strange—hein?"
"No, I can't say it did. The doctors ridiculed it of course. But it was quite a natural suggestion for a layman to make."
"But Monsieur Lawrence is not a layman. You told me yourself that he had started by studying medicine, and that he had taken his degree."
"Yes, that's true. I never thought of that." I was rather startled. "It is odd."
Poirot nodded.
"From the first, his behaviour has been peculiar. Of all the household, he alone would be likely to recognize the symptoms of strychnine poisoning, and yet we find him the only member of the family to uphold strenuously the theory of death from natural causes. If it had been Monsieur John, I could have understood it. He has no technical knowledge, and is by nature unimaginative. But Monsieur Lawrence—no! And now, to-day, he puts forward a suggestion that he himself must have known was ridiculous. There is food for thought in this, mon ami!"
"It's very confusing," I agreed.
"Then there is Mrs. Cavendish," continued
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