'The old lady takes a fancy to you. She decides to leave her money to you. She tells you so.' Poirot paused.

Miss Lemon said 'Yes' again.

'And then the old lady finds out something; perhaps it is a matter of money - she may find that you have not been honest with her. Or it might be more grave still - a medicine that tasted different, some food that disagreed. Anyway, she begins to suspect you of something and she writes to a very famous detective - enfin, to the most famous detective - mel I am to call upon her shortly. And then, as you say, the dripping will be in the fire.

The great thing is to act quickly. And so - before the great detec-tive arrives - the old lady is dead. And the money comes to you.

Tell me, does that seem to you reasonable?'

'Quite reasonable,' said Miss Lemon. 'Quite reasonable for a Russian, that is. Personally, I should never take a post as a com-panion.

I like my duties clearly defined. And of course I should not dream of murdering anyone.'

Poirot sighed. 'How I miss my friend Hastings. He had such an imagination. Such a romantic mindl It is true that he always imagined wrong - but that in itself was a guide.'

Miss Lemon was silent. She had heard about Captain Hastings before, and was not interested. She looked longingly at the typewritten sheet in front of her.

'So it seems to you reasonable,' mused Poirot.

'Doesn't it to you?' 'I am almost afraid it does,' sighed Poirot.

The telephone rang and Miss Lemon went out of the room to answer it. She came back to say 'It's Inspector Sims again.' Poirot hurried to the instrument. ' '/kilo, 'allo. What is that you say?' Sims repeated his statement. 'We've found a packet of strychnine in the girl's bedroom - tucked underneath the mattress. The sergeant's just come in with the news. That about clinches it, I think.' 'Yes,' said Poirot, 'I think that clinches it.' His voice had changed. It rang with sudden confidence.

When he had rung off, he sat down at his writing table and arranged the objects on it in a mechanical manner. He murmured to himself, 'There was something wrong. I felt it - no, not felt.

It must have been something I saw. En avant, the little grey cells.

Ponder - reflect. Was everything logical and in order? The girl her anxiety about the money: Mme Delafontaine; her husband his suggestion of Russians - imbecile, but he is an imbecile; the room; the garden - ahl Yes, the garden.' He sat up very stiff. The green light shone in his eyes. He sprang up and went into the adjoining room.

'Miss Lemon, will you have the kindness to leave what you are doing and make an investigation for me?' 'An investigation, M. Poirot? I'm afraid I'm not very good - ' Poirot interrupted her. 'You said one day that you knew all about tradesmen.' 'Certainly I do,' said Miss Lemon with confidence.

'Then the matter is simple. You are to go to Charman's Green and you are to discover a fishmonger.' 'A fishmonger?' asked Miss Lemon, surprised.

'Precisely. The fishmonger who supplied Rosebank with fish.

When you have found him you will ask him a certain question.' He handed her a slip of paper. Miss Lemon took it, noted its contents without interest, then nodded and slipped the lid on her typewriter.

'We will go to Charman's Green together,' said Poirot. 'You go to the fishmonger and I to the police station. It will take us but half an hour from Baker Street.'

On arrival at his destination, he was greeted by the surprised Inspector Sims. 'Well, this is quick work, M. Poirot. I was talking to you on the phone only an hour ago.'

'I have a request to make to you; that you allow me to see this girl Katrina - what is her name?'

'Katrina Rieger. Well, I don't suppose there's any objection to that.'

The girl Katrina looked even more sallow and sullen than ever.

Poirot spoke to her very gently. 'Mademoiselle, I want you to believe that I am not your enemy. I want you to tell me the truth.'

Her eyes snapped defiantly. 'I have told the truth. To everyone I have told the truth! If the old lady was poisoned, it was not I who poisoned her. It is all a mistake. You wish to prevent me having the money.' Her voice was rasping. She looked, he thought, like a miserable little cornered rat.

'Tell me about this cachet, mademoiselle,' M. Poirot went on.

'Did no one handle it but you?'

'I have said so, have I not? They were made up at the chemist's that afternoon. I brought them back with me in my bag - that was just before supper. I opened the box and gave Miss Barrowby one with a glass of water.'

'No one touched them but you?'

"No.' A cornered rat - with couragel

'And Miss Barrowby had for supper only what we have been told. The soup, the fish pie, the tart?'

'Yes.' A hopeless 'yes' - dark, smouldering eyes that saw no light anywhere.

Poirot patted her shoulder. 'Be of good courage, mademoiselle.

There may yet be freedom - yes, and money - a life of ease.' She looked at him suspiciously.

As he went out Sims said to him, 'I didn't quite get what you aid through the telephone - something about the girl having a friend.' 'She has one. Me!' said Hercule Poirot, and had left the police station before the inspector could pull his wits together.

At the Green Cat tearooms, Miss Lemon did not keep her employer waiting. She went straight to the point.

'The man's name is Rudge, in the High Street, and you were quite right. A dozen and a half exactly. I've made a note of what he said.' She handed it to him.

'Arrr.' It was a deep, rich sound like the purr of a cat.

Hercule?oirot betook himself to Rosebank. As he stood in the front garden, the sun setting behind him, Mary Delafontaine came out to him.

'M. Poirot?' Her voice sounded surprised. 'You have come back?' 'Yes, I have first came here, my head: come back.' He paused and then said, 'When I madame, the children's nursery rhyme came into

Mistress Mary, quite contrary, How does your garden grow?

With cockle-shells, and silver bells, And pretty maids all in a row.

Only they are not cockle shells, are they, madame? They are oyster shells.' His hand pointed.

He heard her catch her breath and then stay very still. Her eyes asked a question.

He nodded. 'Mais, oui, I know! The maid left the dinner ready - she will swear and Katrina will swear that that is all you had.

Only you and your husband know that you brought back a dozen and a half oysters - a little treat pour la bonne tante. So easy to put the strychnine in an oyster. It is swallowed - cornme fa! But there remain the shells - they must not go in the bucket. The maid would see them. And so you thought of making an edging of them to a bed. But there were not enough - the edging is not complete. The effect is bad - it spoils the symmetry of the other244

wise charming garden. Those few oyster shells struck an alien note - they displeased my eye on my first visit.' Mary Delafontaine said, 'I suppose you guessed from the letter. I knew she had written - but I didn't know how much she'd said.' Poirot answered evasively, 'I knew at least that it was a family matter. If it had been a question of Katrina there would have been no point in hushing things up. I understand that you or your husband handled Miss Barrowby's securities to your own profit, and that she found out - ' Mary Delafontaine nodded. 'We've done it for years - a little here and there. I never realized she was sharp enough to find out.

And then I learned she had sent for a detective; and I found out, too, that she was leaving her money to Katrina - that miserable little creature!' 'And so the strychnine was put in Katrina's bedroom? I comprehend.

You save yourself and your husband from what I may discover, and you saddle an innocent child with murder. Had you no pity, madame?' Mary Delafontaine shrugged her shoulders - her blue forget-me°not eyes looked into Poirot's. He remembered the perfection of her acting the first day he had come and the bungling attempts of her husband. A woman above the average - but inhuman.