Roddy’s face was wrathful.
Poirot answered him like a flash:
“You have told me, Mr. Welman, as regards the death of Mary Gerrard, that the motive attributed to Elinor Carlisle is absurd—that she was, emphatically, not that kind of a person. But there is now another interpretation. Elinor Carlisle had reason to fear that she might be disinherited in favour of an outsider. The letter has warned her—her aunt’s broken murmurings confirm that fear. In the h
all below is an attaché case with various drugs and medical supplies. It is easy to abstract a tube of morphine. And afterwards, so I have learned, she sits in the sick room alone with her aunt while you and the nurses are at dinner….”
Roddy cried:
“Good God, M. Poirot, what are you suggesting now? That Elinor killed Aunt Laura? Of all the ridiculous ideas!”
Poirot said:
“But you know, do you not, that an order to exhume Mrs. Welman’s body has been applied for?”
“Yes, I know. But they won’t find anything!”
“Suppose they do?”
“They won’t!” Roddy spoke positively.
Poirot shook his head.
“I am not so sure. And there was only one person, you realize, who would benefit by Mrs. Welman’s dying at that moment….”
Roddy sat down. His face was white and he was shaking a little. He stared at Poirot. Then he said:
“I thought—you were on her side….”
Hercule Poirot said:
“Whatever side one is on, one must face facts! I think, Mr. Welman, that you have so far preferred in life to avoid facing an awkward truth whenever it is possible.”
Roddy said:
“Why harrow oneself by looking on the worst side?”
Hercule Poirot replied gravely:
“Because it is something necessary….”
He paused a minute and then said:
“Let us face the possibility that your aunt’s death may be found to be due to the administration of morphine. What then?”
Roddy shook his head helplessly.
“I don’t know.”
“But you must try to think. Who could have given it to her? You must admit that Elinor Carlisle had the best opportunity to do so?”
“What about the nurses?”
“Either of them could have done so, certainly. But Nurse Hopkins was concerned about the disappearance of the tube at the time and mentioned it openly. There was no need for her to do so. The death certificate had been signed. Why call attention to the missing morphine if she were guilty? It will probably bring her censure for carelessness as it is, and if she poisoned Mrs. Welman it was surely idiotic to draw attention to the morphine. Besides, what could she gain by Mrs. Welman’s death? Nothing. The same applies to Nurse O’Brien. She could have administered morphine, could have taken it from Nurse Hopkins’ case; but, again—why should she?”
Roddy shook his head.
“All that’s true enough.”