Poirot’s Early Cases by Agatha Christie

I did not as yet see that this little incident was of any use to me, yet I determined to investigate it as being out of the ordinary. I rang the bell for François, and asked him if his late master had been fond of sweets. A faint melancholy smile came to his lips.

‘Passionately fond of them, monsieur. He would always have a box of chocolates in the house. He did not drink wine of any kind, you see.’

‘Yet this box has not been touched?’ I lifted the lid to show him.

‘Pardon, monsieur, but that was a new box purchased on the day of his death, the other being nearly finished.’

‘Then the other box was finished on the day of his death,’ I said slowly.

‘Yes, monsieur, I found it empty in the morning and threw it away.’

‘Did M. Déroulard eat sweets at all hours of the day?’

‘Usually after dinner, monsieur.’

I began to see light.

‘François,’ I said, ‘you can be discreet?’

‘If there is need, monsieur.’

‘Bon! Know, then, that I am of the police. Can you find me that other box?’

‘Without doubt, monsieur. It will be in the dustbin.’

He departed, and returned in a few minutes with a dust-covered object. It was the duplicate of the box I held, save for the fact that this time the box was blue and the lid was pink. I thanked François, recommended him once more to be discreet, and left the house in the Avenue Louise without more ado.

Next I called upon the doctor who had attended M. Déroulard. With him I had a difficult task. He entrenched himself prettily behind a wall of learned phraseology, but I fancied that he was not quite as sure about the case as he would like to be.

‘There have been many curious occurrences of the kind,’ he observed, when I had managed to disarm him somewhat. ‘A sudden fit of anger, a violent emotion—after a heavy dinner, c’est entendu—then, with an access of rage, the blood flies to the head, and pst!—there you are!’

‘But M. Déroulard had had no violent emotion.’

‘No? I made sure that he had been having a stormy altercation with M. de Saint Alard.’

‘Why should he?’

‘C’est évident!’ The doctor shrugged his shoulders. ‘Was not M. de Saint Alard a Catholic of the most fanatical? Their friendship was being ruined by this question of church and state. Not a day passed without discussions. To M. de Saint Alard, Déroulard appeared almost as Antichrist.’

This was unexpected, and gave me food for thought.

‘One more question, Doctor: would it be possible to introduce a fatal dose of poison into a chocolate?’

‘It would be possible, I suppose,’ said the doctor slowly. ‘Pure prussic acid would meet the case if there were no chance of evaporation, and a tiny globule of anything might be swallowed unnoticed—but it does not seem a very likely supposition. A chocolate full of morphine or strychnine—’ He made a wry face. ‘You comprehend, M. Poirot—one bite would be enough! The unwary one would not stand upon ceremony.’

‘Thank you, M. le Docteur.’

I withdrew. Next I made inquiries of the chemists, especially those in the neighbourhood of the Avenue Louise. It is good to be of the police. I got the information I wanted without any trouble. Only in one case could I hear of any poison having been supplied to the house in question. This was some eye drops of atropine sulphate for Madame Déroulard. Atropine is a potent poison, and for the moment I was elated, but the symptoms of atropine poisoning are closely allied to those of ptomaine, and bear no resemblance to those I was studying. Besides, the prescription was an old one. Madame Déroulard had suffered from cataracts in both eyes for many years.

I was turning away discouraged when the chemist’s voice called me back.

‘Un moment, M. Poirot. I remember, the girl who brought that prescription, she said something about having to go on to the English chemist. You might try there.’

I did. Once more enforcing my official status, I got the information I wanted. On the day before M. Déroulard’s death they had made up a prescription for Mr John Wilson. Not that there was any making up about it. They were simply little tablets of trinitrine. I asked if I might see some. He showed me them, and my heart beat faster—for the tiny tablets were of chocolate.