‘Never knew who or what struck her,’ observed the sergeant. ‘That’s what Dr Kerr says. I’m glad it was that way, poor old soul. A decent woman she was.’

‘She must have been beautiful once,’ said Poirot.

‘Really?’ I murmured incredulously.

‘But yes, look at the line of the jaw, the bones, the moulding of the head.’

He sighed as he replaced the sheet and we left the mortuary.

Our next move was a brief interview with the police surgeon.

Dr Kerr was a competent-looking middle-aged man. He spoke briskly and with decision.

‘The weapon wasn’t found,’ he said. ‘Impossible to say what it may have been. A weighted stick, a club, a form of sandbag—any of those would fit the case.’

‘Would much force be needed to strike such a blow?’

The doctor shot a keen glance at Poirot.

‘Meaning, I suppose, could a shaky old man of seventy do it? Oh, yes, it’s perfectly possible—given sufficient weight in the head of the weapon, quite a feeble person could achieve the desired result.’

‘Then the murderer could just as well be a woman as a man?’

The suggestion took the doctor somewhat aback.

‘A woman, eh? Well, I confess it never occurred to me to connect a woman with this type of crime. But of course it’s possible—perfectly possible. Only, psychologically speaking, I shouldn’t say this was a woman’s crime.’

Poirot nodded his head in eager agreement.

‘Perfectly, perfectly. On the face of it, highly improbable. But one must take all possibilities into account. The body was lying—how?’

The doctor gave us a careful description of the position of the victim. It was his opinion that she had been standing with her back to the counter (and therefore to her assailant) when the blow had been struck. She had slipped down in a heap behind the counter quite out of sight of anyone entering the shop casually.

When we had thanked Dr Kerr and taken our leave, Poirot said:

‘You perceive, Hastings, that we have already one further point in favour of Ascher’s innocence. If he had been abusing his wife and threatening her, she would have been facing him over the counter. Instead she had her back to her assailant—obviously she is reaching down tobacco or cigarettes for a customer.’

I gave a little shiver.

‘Pretty gruesome.’

Poirot shook his head gravely.

‘Pauvre femme,’ he murmured.

Then he glanced at his watch.

‘Overton is not, I think, many miles from here. Shall we run over there and have an interview with the niece of the dead woman?’

‘Surely you will go first to the shop where the crime took place?’

‘I prefer to do that later. I have a reason.’

He did not explain further, and a few minutes later we were driving on the London road in the direction of Overton.

The address which the inspector had given us was that of a good-sized house about a mile on the London side of the village.

Our ring at the bell was answered by a pretty dark-haired girl whose eyes were red with recent weeping.