She has lunch and appears much as usual.
It has been said of her that she looks a little worried and preoccupied.
That does not help us, for there is no criterion of behavior for a murderer.
There are calm murderers and excited murderers.
"After lunch she goes down again to the Battery.
She discovers her husband dead, and does, shall we say, the obviously expected things. She registers emotion and she sends the governess to telephone for a doctor.
We now come to a fact which has previously not been known."
He looked at Miss Williams.
"You do not object?"
Miss Williams was rather pale.
She said, "I did not pledge you to secrecy."
Quietly, but with telling effect, Poirot recounted what the governess had seen.
Elsa Dittisham moved her position. She stared at the drab little woman in the big chair.
She said incredulously,
"You actually saw her do that?"
Philip Blake sprang up.
"But that settles it!" he shouted.
"That settles it once and for all."
Hercule Poirot looked at him mildly. He said,
"Not necessarily."
Angela Warren said sharply,
"I don't believe it." There was a quick, hostile glint in the glance she shot at the little governess.
Meredith Blake was pulling at his mustache, his face dismayed.
Alone, Miss Williams remained undisturbed.
She sat very upright and there was a spot of color in each check.
She said, "That is what I saw."
Poirot said slowly,
"There is, of course, only your word for it..."
"There is only my word for it." The indomitable gray eyes met his. "I am not accustomed, M. Poirot, to having my word doubted."
Hercule Poirot bowed his head.
He said, "I do not doubt your word, Miss Williams.
What you saw took place exactly as you say it did, and because of what you saw I realized that Caroline Crale was not guilty - could not possibly be guilty."
For the first time, that tall, anxious-faced young man, John Rattery, spoke. He said,
"I'd be interested to know why you say that, M. Poirot."
Poirot turned to him.
"Certainly. I will tell you.
What did Miss Williams see?
She saw Caroline Crale very carefully and anxiously wiping off fingerprints and subsequently imposing her dead husband's fingerprints on the beer bottle.
On the beer bottle, mark.
But the coniine was in the glass - not in the bottle.
The police found no traces of coniine in the bottle.
There had never been any coniine in the bottle.
And Caroline Crale didn't know that.
"She, who is supposed to have poisoned her husband, didn't know how he had been poisoned.
She thought the poison was in the bottle."
Meredith objected.
"But why -"
Poirot interrupted him in a flash:
"Yes - why?
Why did Caroline Crale try so desperately to establish the theory of suicide.