As I say, up till the Monday evening, my narrative might have been that of Poirot himself. I played Watson to his Sherlock. But after Monday our ways diverged. Poirot was busy on his own account. I got to hear of what he was doing, because in King's Abbot, you get to hear of everything, but he did not take me into his confidence beforehand. And I, too, had my own preoccupations.

After the evening talk I have just chronicled, the affair seemed to me to enter on a different phase. The whole thing can be divided into two parts, each clear and distinct from the other. Part I ranges from Ackroyd's death on the Friday evening to the following Monday night. It is the straightforward narrative of what occurred, as presented to Hercule Poirot. I was at Poirot's elbow the whole time. I saw what he saw. I tried my best to read his mind. As I know now, I failed in this latter task. Though Poirot showed me all his discoveries -- as, for instance, the gold wedding-ring -- he held back the vital and yet logical impressions that he formed. As I came to know later, this secrecy was characteristic of him. He would throw out hints and suggestions, but beyond that he would not go.

Some of the incidents seemed at the time irrelevant and unmeaning. There was, for instance, the question of the black boots. But that comes later… To take things strictly in chronological order, I must begin with the summons from Mrs Ackroyd.

On looking back, the thing that strikes me most is the piecemeal character of this period. Everyone had a hand in the elucidation of the mystery. It was rather like a jigsaw puzzle to which everyone contributed their own little piece of knowledge or discovery. But their task ended there. To Poirot alone belongs the renown of fitting those pieces into their correct place.

She sent for me early on Tuesday morning, and since the summons sounded an urgent one, I hastened there, expecting to find her in extremis.

The lady was in bed. So much did she concede to the etiquette of the situation. She gave me her bony hand, and indicated a chair drawn up to the bedside.

"Well, Mrs Ackroyd," I said, "and what's the matter with you?" I spoke with that kind of spurious geniality which seems to be expected of general practitioners.

"I'm prostrated," said Mrs Ackroyd in a faint voice. "Absolutely prostrated. It's the shock of poor Roger's death. They say these things often aren't felt at the time, you know. It's the reaction afterwards."

I would have given anything to be able to answer "Bunkum!" Instead, I suggested a tonic. Mrs Ackroyd accepted the tonic. One move in the game seemed now to be concluded.

It is a pity that a doctor is precluded by his profession from being able sometimes to say what he really thinks.

Not for a moment did I imagine that I had been sent for because of the shock occasioned by Ackroyd's death. But Mrs Ackroyd is totally incapable of pursuing a straightforward course on any subject. She always approaches her object by tortuous means. I wondered very much why it was she had sent for me.

"And then that scene -- yesterday," continued my patient.

"What scene?"

She paused as though expecting me to take up a cue.

"Doctor, how can you? Have you forgotten? That dreadful little Frenchman -- or Belgian -- or whatever he is. Bullying us all like he did. It has quite upset me. Coming on the top of Roger's death."

"No one can say that I have failed in my duty," continued Mrs Ackroyd. "I am sure Inspector Raglan is perfectly satisfied. Why should this little upstart of a foreigner make a fuss? A most ridiculous-looking creature he is too -- just like a comic Frenchman in a revue. I can't think why Flora insisted on bringing him into the case. She never said a word to me about it. Just went off and did it on her own. Flora is too independent. I am a woman of the world and her mother. She should have come to me for advice first."

I listened to all this in silence.

"I don't know what he meant -- shouting at us like he ^d. I should hope I know my duty too well to dream of concealing anything. I have given the police every assistance in my power."

"I'm very sorry, Mrs Ackroyd," I said.

Mrs Ackroyd paused, and I said, "Quite so." I was beginning to have a glimmering of what all the trouble was about.

"What does he think? That's what I want to know. Does he actually imagine I'm hiding something? He -- he -- positively accused me yesterday."

Mrs Ackroyd went off at a tangent, after her usual fashion.

"Servants are so tiresome," she said. "They gossip, and talk amongst themselves. And then it gets round -- and all the time there's probably nothing in it at all."

I shrugged my shoulders.

"It is surely of no consequence, Mrs Ackroyd," I said. "Since you are not concealing anything, any remarks he may have made do not apply to you."

Mrs Ackroyd cast a very shrewd glance at me. It quite threw me off my balance.

"Have the servants been talking?" I asked. "What about?"

"I was."

"Then of course you know. It was that girl, Ursula Bourne, wasn't it? Naturally -- she's leaving. She would want to make all the trouble she could. Spiteful, that's what they are. They're all alike. Now, you being there, doctor, you must know exactly what she did say? I'm most anxious,,. no wrong impression should get about. After all, you "don't repeat every little detail to the police, do you? There are family matters sometimes -- nothing to do with the Question of the murder. But if the girl was spiteful, she may have made out all sorts of things."

"I was sure you'd know, doctor, if anyone did. You were with M. Poirot all the time, weren't you?"

"If I were you, Mrs Ackroyd," I said brusquely, "I should make a clean breast of things."

"Then why not do so?" I suggested.

She gave a little scream. "Oh! doctor, how can you be so abrupt. It sounds as though -- as though -- And I can explain everything so simply."

I was shrewd enough to see that a very real anxiety lay behind these outpourings. Poirot had been justified in his premises. Of the six people round the table yesterday, Mrs Ackroyd at least had had something to hide. It was for me to discover what that something might be.

Mrs Ackroyd took out a frilled handkerchief, and became tearful.

"I thought, doctor, that you might put it to M. Poirot explain it, you know -- because it's so difficult for a foreigner to see our point of view. And you don't know -- nobody could know -- what I've had to contend with. A martyrdom -- a long martyrdom. That's what my life has been. I don't like to speak ill of the dead -- but there it is. Not the smallest bill but it had all to be gone over -- just as though Roger had had a few miserly hundreds a year instead of being (as Mr Hammond told me yesterday) one of the wealthiest men in these parts."

Mrs Ackroyd paused to dab her eyes with the frilled handkerchief.

"Yes," I said encouragingly. "You were talking about bills?"

"It's a habit they have," I agreed.

"Ten pounds to ten thousand on note of hand alone," murmured Mrs Ackroyd reminiscently. "I wrote to one of them, but it seemed there were difficulties." She paused.

"Those dreadful bills. And some I didn't like to show Roger at all. They were things a man wouldn't understand. He would have said the things weren't necessary. And of course they mounted up, you know, and they kept coming in --"

She looked at me appealingly, as though asking me to condole with her on this striking peculiarity.

"Hardly that," I said drily. "They are usually Scotch gentlemen, but I suspect a Semitic strain in their ancestry."

And the tone altered -- became quite abusive. "I assure you, doctor, I was becoming a nervous wreck. I couldn't sleep at nights. And a dreadful fluttering round the heart. And then I got a letter from a Scotch gentleman -- as a matter of fact there were two letters -- both Scotch gentlemen. Mr Bruce MacPherson was one, and the other was Colin MacDonald. Quite a coincidence."

"You see," murmured Mrs Ackroyd, "it's all a question of expectations," isn't it? Testamentary expectations. And though, of course, I expected that Roger would provide for me, I didn't know. I thought that if only I could glance over a copy of his will -- not in any sense of vulgar prying -- but just so that I could make my own arrangements." She glanced sideways at me. The position was now very delicate indeed. Fortunately words, ingeniously used, will serve to mask the ugliness of naked facts.

I gathered that we were just coming to delicate ground. I have never known anyone more difficult to bring to the point.

"I could only tell this to you, dear Doctor Sheppard," said Mrs Ackroyd rapidly. "I can trust you not to misjudge me, and to represent the matter in the right light to M. Poirot. It was on Friday afternoon --" She came to a stop and swallowed uncertainly.

"Yes," I repeated encouragingly. "On Friday afternoon. Well?"

"Everyone was out, or so I thought. And I went into Roger's study -- I had some real reason for going there -- I mean, there was nothing underhand about it. And as I saw all the papers heaped on the desk, it just came to me, like a flash: "I wonder if Roger keeps his will in one of the drawers of the desk." I'm so impulsive, always was, from a child. I do things on the spur of the moment. He'd left his keys -- very careless of him -- in the lock of the top drawer."

Mrs Ackroyd gave a little scream, and I realized that I had not been sufficiently diplomatic.

"I see," I said helpfully. "So you searched the desk. Did you find the will?"

"Of course it wasn't," I said hastily. "You must forgive my unfortunate way of putting things."

"Of course, men are so peculiar. In dear Roger's place, I should have not objected to revealing the provisions of my will. But men are so secretive. One is forced to adopt little subterfuges in self-defence."

"How dreadful it sounds. But it wasn't at all like that really."

"And the result of the little subterfuge?" I asked.

"That's just what I'm telling you. As I got to the bottom drawer. Bourne came in. Most awkward. Of course I shut the drawer and stood up, and I called her attention to a few specks of dust on the surface. But I didn't like the way she looked -- quite respectful in manner, but a very nasty light in her eyes. Almost contemptuous, if you know what I mean. I never have liked that girl very much. She's a good servant, and she says Ma'am, and doesn't object to wearing caps and aprons (which I declare to you a lot of them do nowadays), and she can say "Not at home" without scruples if she has to answer the door instead of Parker, and she doesn't have those peculiar gurgling noises inside which so many parlourmaids seem to have when they wait at table Let me see, where was I?"

"You will explain to M. Poirot, won't you? You can see for yourself what a trivial matter the whole thing was. But, of course, when he was so stern about concealing things, I thought of this at once. Bourne may have made some extraordinary story out of it, but you can explain, can't you?"

"No more I do. She's -- odd. There's something different about her from the others. Too well educated, that's my "pinion. You can't tell who are ladies and who aren't nowadays."

"Nothing. At least, Roger came in. And I thought he was out for a walk. And he said: "What's all this?" and I said "Nothing. I just came in to fetch Punch." And I took Punch and went out with it. Bourne stayed behind. I heard her asking Roger if she could speak to him for a minute. I went straight up to my room, to lie down. I was very upset." There was a pause.

"You were saying, that in spite of several valuable qualities, you never liked Bourne."

"That is all?" I said. "You have told me everything?"

"And what happened next?" I asked.

"Ye-es," said Mrs Ackroyd. "Oh! yes," she added firmly.

It was nothing less than a flash of sheer genius that prompted me to ask the question I did. "Mrs Ackroyd," I said, "was it you who left the silver table open?" I had my answer in the blush of guilt that even rouge and powder could not conceal.

"It was you, then?"

But I had noted the momentary hesitation, and I knew that there was still something she was keeping back.

"Yes -- I -- you see -- there were one or two pieces of old silver -- very interesting. I had been reading up the subject and there was an illustration of quite a small piece which had fetched an immense sum at Christy's. It looked to be just the same as the one in the silver table. I thought I would take it up to London with me when I went -- and -- and have it valued. Then if it really was a valuable piece, just think what a charming surprise it would have been for Roger."

I refrained from comments, accepting Mrs Ackroyd's story on its merits. I even forbore to ask her why it was necessary to abstract what she wanted in such a surreptitious manner.

"How did you know?" she whispered.

Mrs Ackroyd had revealed to me one fact that was extremely interesting. Whether her designs upon Ackroyd's silver had been strictly honourable I neither knew nor cared. What did interest me was the fact that Miss Russell must have entered the drawing-room by the window, and that I had not been wrong when I judged her to be out of breath with running. Where had she been? I thought of the summer-house and the scrap of cambric.

"Why did you leave the lid open?" I asked. "Did you forget?"

"I was startled," said Mrs Ackroyd. "I heard footsteps coining along the terrace outside. I hastened out of the room and just got up the stairs before Parker opened the front door to you."

"I wonder if Miss Russell has had her handkerchiefs starched!" I exclaimed on the spur of the moment.

"You think you can explain to M. Poirot?" she asked anxiously.

"That must have been Miss Russell," I said thoughtfully.

Mrs Ackroyd's start recalled me to myself, and I rose.

"Oh, certainly. Absolutely." I got away at last, after being forced to listen to more justifications of her conduct.

The parlourmaid was in the hall, and it was she who helped me on with my overcoat. I observed her more closely than I had done heretofore. It was clear that she had been crying.

"How is it," I asked, "that you told us that Mr Ackroyd sent for you on Friday to his study? I hear now that it was you who asked to speak to him."

I shook my head, looking at her inquiringly.

For a minute the girl's eyes dropped before mine. Then she spoke. "I meant to leave in any case," she said uncertainly.

I said no more. She opened the front door for me. Just as I was passing out, she said suddenly in a low voice: "Excuse me, sir, is there any news of Captain Paton?"

"He ought to come back," she said. "Indeed -- indeed he degught to come back." She was looking at me with appealing eyes.

"Does no one know where he is?" she asked.

"Do you?" I said sharply.

She shook her head. "No, indeed. I know nothing. But anyone who was a friend to him would tell him this: he ought to come back."

I lingered, thinking that perhaps the girl would say more.

"Not earlier? Not before a quarter to ten?" I looked at her attentively. She was so clearly eager for a reply in the affirmative.

Her next question surprised me.

"That's out of the question," I said. "Miss Ackroyd saw her uncle alive at a quarter to ten."

"I am helping him with the case," she explained.

"When do they think the murder was done? Just before ten o'clock?"

"That is the idea," I said. "Between a quarter to ten and the hour."

Caroline was at home. She had had a visit from Poirot and was very pleased and important about it.

"A handsome girl," I said to myself as I drove off. "An exceedingly handsome girl."

I felt rather uneasy. Caroline is bad enough as it is. What will she be like with her detective instincts encouraged?

She turned away, and her whole figure seemed to droop.

"Are you going round the neighbourhood looking for Ralph Paton's mysterious girl?" I inquired.

"I might do that on my own account," said Caroline. "No, this is a special thing M. Poirot wants me to find out for him."

I stared at her. I see now that I was unbelievably stupid about these boots. I failed altogether to grasp the point.

"What is it?" I asked.

"He wants to know whether Ralph Paton's boots were black or brown," said Caroline with tremendous solemnity.

"Not shoes, James, boots. M. Poirot wants to know whether a pair of boots Ralph had with him at the hotel were brown or black. A lot hangs on it."

"They were brown shoes," I said. "I saw them."

It was when we were sitting down to lunch that Caroline remarked, with would-be unconcern: "About those boots of Ralph Paton's."

Call me dense if you like. I didn't see.

"And how are you going to find out?" I asked.

Caroline said there would be no difficulty about that. Our Annie's dearest friend was Miss Gannett's maid, Clara. And Clara was walking out with the Boots at the Three Boars. The whole thing was simplicity itself, and by the aid of Miss Gannett, who co-operated loyally, at once giving Clara leave of absence, the matter was rushed through at express speed.

"Well," I said, "what about them?"

"M. Poirot thought they were probably brown. He was wrong. They're black." And Caroline nodded her head several times. She evidently felt that she had scored a point over Poirot.

I did not answer. I was puzzling over what the colour of a pair of Ralph Paton's boots had to do with the case.