Miss Silver explored with the stick. There was nearly three feet of water, and there was no stone upon which Mabel Preston could have hit her head. Cocktails are extremely insidious. She had taken a considerable number of them, but she had not been too much under the influence of alcohol to make her way to this place, and though she may not have been quite steady on her feet, yet the sudden shock of falling head foremost into cold water should certainly have produced some reaction. Her hands would have been able to reach the bottom. There should have been a struggle, an attempt to save herself. How, in that case, was it possible to believe that the lower limbs would remain in the position assumed at the moment of the fall? Adriana had questioned Sam Bolton, and questioned him shrewdly. The dead woman’s knees were still on the parapet when he was trying to get her out of the pool. She had repeated his words – ‘I’d never have done it else, not if it was ever so. What I did, I got down in the pool and I pushed her up, and hard work it was and no mistake.’

It would have been hard work to move that dead dripping thing weighed down by the soaking coat, but when Mabel Preston fell she was alive and the stuff was dry. It would take time for the heavy material to become sodden. Then why had there been no straggle, no reaction to the shock of the cold water? Why did a living, breathing woman just lie as she had fallen and let the water drown her? Try as she would, Miss Silver could find only one explanation. Mabel Preston had been pushed, and the person who pushed her had held her under the water until its work was done.

It was a shocking conclusion, but she could come to no other. She considered whether it would be possible to kneel upon the parapet or behind it and carry out this dreadful act. The low wall was some eighteen inches above the paving which surrounded it, but on the pool side the water rose to within three or four inches of the top, a circumstance no doubt due to the recent heavy rains. If the author of the murderous attack had leaned over the parapet or kneeled upon it, it would have been perfectly possible to ensure that the woman who had fallen should not rise again.

She wore her gravest expression as she turned to go. Here, on this warm afternoon with the blue of the sky reflected in the pool and the sun bright upon the water, it was a pleasant place. There would be sunshine and blue skies in the time to come, but she wondered how long it would be before anyone would sit here alone for his pleasure, or without remembering that here murder had been done. She was as sure about it as that.

But there was no one who had any reason to wish Mabel Preston dead. If she had been murdered, it was because she had been taken for someone else. She had dyed her hair in imitation of Adriana Ford’s. She went to her death in Adriana’s coat. Adriana’s own description of it came to her mind – great black and white squares and an emerald stripe. Even in the dusk, or by the faltering light of an electric torch, such a pattern would leap to the eye. And Adriana had worn the coat so long that she would not let Meriel have it. ‘Too well known, and people would say I made her wear out my old clothes. She might even come to saying it herself. Meriel is like that.’ Was not that what Adriana had said – that or something like it?

As she passed under the arch in the hedge, the sun picked up a point of colour and she stopped. Caught between one twig and another was a wisp of stuff. It was the merest shred, and if the sun had not shone directly on it, she would have passed it by. When she had disentangled it, she had a few silky threads of the colour known as cyclamen. She put them carefully into the palm of her glove and returned to the house.

Invited to tea with Adriana in her own sitting-room, she displayed the shred.

‘Has anyone in the house a dress of this colour?’

Adriana looked at it with disfavour.

‘Meriel has – and quite horribly unbecoming. You’ve got to have white hair, a good skin, and perfect make-up, before you can look at magenta. Meriel isn’t nearly smart enough, and she doesn’t take enough trouble. She wore the dress for the party, and she looked ghastly. Her lipstick clashed by about three shades! But it’s no use telling her anything like that – she just flies into a temper. Where did you get these threads? I shan’t be sorry if she’s torn the dress and can’t wear it any more. Well, where did you get them?’

‘They were caught on the hedge which surrounds the pool.’

Adriana said sharply,

‘On the hedge?’

‘On the inner side of one of the arches. I saw them as I was coming away. I should not have noticed them if the sun had not happened to pick them out.’

Adriana said nothing. Her face became a mask. Before she could speak Meeson came in with the tea. Just as she was going out again Adriana called to her.

‘Gertie, take a look at this!’ She held out the scrap of stuff.

Meeson made a clicking sound with her tongue.

‘Well now, isn’t that Meriel all over! Pays twenty guineas for a dress, and I know she did that, for I saw the bill – left it lying about in her room and the wind blew it down on the floor! And then goes and mucks it up first time she wears it!’

‘Oh, she mucked it up, did she? On Saturday?’

Meeson nodded.

‘Can’t say I was struck on the dress, but she mucked it up properly! Coffee all down the front of it, and cleaners or no cleaners, it’s never going to come out!’

‘So she spilt coffee on it?’

‘Said someone jogged her elbow. “Lord!” I said. “What have you been doing to yourself?” and she said someone had jogged her elbow. “Well,” I said, “you’re never going to get that out this side of kingdom come – not coffee, you can take my word for it!” And she goes pushing past me as if I wasn’t there! But that’s Meriel all over! What she’s done herself, well, it’s always got to be somebody else’s fault! That’s her from a baby!’

She might have gone on, but she was interrupted sharply.

‘When was all this?’

‘When was what, ducks?’

Adriana made an impatient gesture.

‘This coffee-spilling business.’

‘How do I know?’

‘You know when you saw Meriel’s dress with the coffee on it.’

Meeson cast up her eyes.

‘Oh, that? Let’s see – it would be somewhere about the time everyone was getting a move on, for I thought to myself, “Well, anyhow the party’s as good as over, which is better than if it had happened earlier on.”

‘What has she done with the dress?’

‘Took it off to the cleaner’s on the Monday. But they’ll never get those stains out, and so I told her. “Have it dyed,” I said, “and make a job of it – black, or brown, or a good navy. Always very ladylike, a good navy is.” And for once in a way she hadn’t got anything to say.’

When Meeson was gone Adriana looked defiantly at Miss Silver and said,

‘Well?’

Miss Silver had been knitting in a very thoughtful manner. She was, in fact, engaged in the process known as putting two and two together. They added up to an ugly four. She said,

‘What do you make of it yourself, Miss Ford?’

Adriana lifted the teapot and began to pour out. Her hand was perfectly steady.

‘She went down to the pool at some time when she was wearing the dress.’

‘Yes.’

‘She was in the drawing-room during all the time that people were arriving, but after the room got very full I can’t say whether she was there or not. She could have slipped out – only why should she?’

‘She had not worn that dress before?’

‘No.’

‘Then she did go out, since I found a torn shred from it caught on the hedge by the pool.’

Adriana said, ‘Do you take milk and sugar?’

Miss Silver gave her slight formal cough.

‘Milk, if you please, but no sugar.’ She laid down her knitting, took the cup, and continued as if there had been no interruption. ‘We have, then, two certain facts. Miss Meriel went down to the pool, and at some time towards the end of the party she told Meeson that she had spilt coffee on her dress. Did you notice the stains yourself? Either during the party or afterwards?’