"If you are asking me who had the most violent temper in the house -"Poirot held up a hand.

"Ah! But that is not the question I should ask," he said softly. "My question would be, who has thebest temper?"Parsons stared at him open-mouthed.

Poirot wasted no further time on him. With an amiable little bow - he was always amiable - he leftthe room and wandered out into the big square hall of Mon Repos. There he stood a minute or twoin thought, then, at a slight sound that came to him, cocked his head on one side in the manner of aperky robin, and finally, with noiseless steps, crossed to one of the doors that led out of the hall.

He stood in the doorway, looking into the room; a small room furnished as a library. At a big deskat the further end of it sat a thin, pale young man busily writing. He had a receding chin, and worea pince-nez.

Poirot watched him for some minutes, and then he broke the silence by giving a completelyartificial and theatrical cough.

"Ahem!" coughed M. Hercule Poirot.

The young man at the desk stopped writing and turned his head. He did not appear unduly startled,but an expression of perplexity gathered on his face as he eyed Poirot.

The latter came forward with a little bow.

"I have the honor of speaking to M. Trefusis, yes? Ah! my name is Poirot, Hercule Poirot. Youmay perhaps have heard of me.""Oh - er - yes, certainly," said the young man.

Poirot eyed him attentively.

Owen Trefusis was about thirty-three years of age, and the detective saw at once why nobody wasinclined to treat Lady Astwell's accusation seriously. Mr Owen Trefusis was a prim, proper youngman, disarmingly meek, the type of man who can be, and is, systematically bullied. One could feelquite sure that he would never display resentment.

"Lady Astwell sent for you, of course," said the secretary. "She mentioned that she was going todo so. Is there any way in which I can help you?"His manner was polite without being effusive. Poirot accepted a chair, and murmured gently:

"Has Lady Astwell said anything to you of her beliefs and suspicions?"Owen Trefusis smiled a little.

"As far as that goes," he said, "I believe she suspects me. It is absurd, but there it is. She has hardlyspoken a civil word to me since, and she shrinks against the wall as I pass by."His manner was perfectly natural, and there was more amusement than resentment in his voice.

Poirot nodded with an air of engaging frankness.

"Between ourselves," he explained, "she said the same thing to me. I did not argue with her - me, Ihave made it a rule never to argue with very positive ladies. You comprehend, it is a waste oftime.""Oh, quite."

"I say, yes, Milady - oh, perfectly, Milady - precisement, Milady. They mean nothing, thosewords, but they soothe all the same. I make my investigations, for though it seems almostimpossible that anyone except M. Leverson could have committed the crime, yet - well, theimpossible has happened before now.""I understand your position perfectly," said the secretary. "Please regard me as entirely at yourservice.""Bon," said Poirot. "We understand one another. Now recount to me the events of that evening.

Better start with dinner."

"Leverson was not at dinner, as you doubtless know," said the secretary. "He had a seriousdisagreement with his uncle, and went off to dine at the Golf Club. Sir Reuben was in a very badtemper in consequence.""Not too amiable, ce Monsieur, eh?" hinted Poirot delicately.

Trefusis laughed.

"Oh! He was a Tartar! I haven't worked with him for nine years without knowing most of his littleways. He was an extraordinarily difficult man, M. Poirot. He would get into childish fits of rageand abuse anybody who came near him. I was used to it by that time. I got into the habit of payingabsolutely no attention to anything he said. He was not bad-hearted really, but he could be mostfoolish and exasperating in his manner. The great thing was never to answer him back.""Were other people as wise as you were in that respect?"Trefusis shrugged his shoulders.

"Lady Astwell enjoyed a good row," he said. "She was not in the least afraid of Sir Reuben, andshe always stood up to him and gave him as good as she got. They always made up afterward, andSir Reuben was really devoted to her.""Did they quarrel that last night?"

The secretary looked at him sideways, hesitated a minute, then he said:

"I believe so; what made you ask?"

"An idea, that is all."

"I don't know, of course," explained the secretary, "but things looked as though they were workingup that way."Poirot did not pursue the topic.

"Who else was at dinner?"

"Miss Margrave, Mr Victor Astwell, and myself.""And afterward?""We went into the drawing-room. Sir Reuben did not accompany us. About ten minutes later hecame in and hauled me over the coals for some trifling matter about a letter. I went up with him tothe Tower room and set the thing straight; then Mr Victor Astwell came in and said he hadsomething he wished to talk to his brother about, so I went downstairs and joined the two ladies.

"About a quarter of an hour later I heard Sir Reuben's bell ringing violently, and Parsons came tosay I was to go up to Sir Reuben at once. As I entered the room, Mr Victor Astwell was comingout. He nearly knocked me over. Something had evidently happened to upset him. He has a veryviolent temper. I really believe he didn't see me.""Did Sir Reuben make any comment on the matter?""He said: 'Victor is a lunatic; he will do for somebody some day when he is in one of these rages.'""Ah!" said Poirot. "Have you any idea what the trouble was about?""I couldn't say at all."Poirot turned his head very slowly and looked at the secretary. Those last words had been utteredtoo hastily. He formed the conviction that Trefusis could have said more had he wished to do so.

But once again Poirot did not press the question.

"And then? Proceed, I pray of you."

"I worked with Sir Reuben for about an hour and a half. At 11 o'clock Lady Astwell came in, andSir Reuben told me I could go to bed.""And you went?"

"Yes."

"Have you any idea how long she stayed with him?""None at all. Her room is on the first floor, and mine is on the second, so I would not hear her goto bed.""I see."

Poirot nodded his head once or twice and sprang to his feet.

"And now, Monsieur, take me to the Tower room."He followed the secretary up the broad stairs to the first landing. Here Trefusis led him along thecorridor, and through a baize door at the end of it, which gave on the servants staircase and on ashort passage that ended in a door. They passed through this door and found themselves on thescene of the crime.

It was a lofty room twice as high as any of the others, and was roughly about thirty feet square.

Swords and assegais adorned the walls, and many native curios were arranged about on tables. Atthe far end, in the embrasure of the window, was a large writing table. Poirot crossed straight to it.

"It was here Sir Reuben was found?"

Trefusis nodded.

"He was struck from behind, I understand?"

Again the secretary nodded.