Three days after the finding of the carter, Dubois, and La Touche’s discovery of what he believed was the true solution of the mystery, he received a letter which interested him considerably. It came by post to his hotel, and was as follows— ‘Rue St. Jean 1,                                  
‘Avenue De L’Alma                 
‘26th May, 1912.            
‘Dear Monsieur,—In connection with your calls here and inquiries into the death of my late mistress, I have just by accident hit on a piece of information which I am sure would be of value to you. It explains the closing of the front door which, you will recollect, I heard about 1.0 a.m. on the night of the dinner party. I think it will have the effect of entirely clearing your client, though I am afraid it does not point to any one else as the murderer. M. Boirac is dining out to-night and most of the servants are attending the marriage festivities of one of the housemaids; the house is therefore unprotected, and I cannot leave it to call on you, but if you could see your way to call here any time during the evening, I shall tell you what I have learnt.
‘Yours respectfully,                                        
‘Henri Fran?ois.’            
 
‘Extraordinary,’ thought La Touche, ‘how, when you get some information about a case, more nearly always comes in. Here I worked for ages on this case without getting any forrader, and Fran?ois made no discoveries to encourage me. Now, when I have almost solved it and it no longer matters, he comes forward with his help. I suppose it’s the inverse of misfortunes never coming singly.’
He looked at his watch. It was just five o’clock. M. Boirac might not leave home till nearly eight. If he went a few minutes past that hour he could see Fran?ois and hear his news.
He wondered what the butler could have discovered. If it really did what he claimed—explained the closing of the front door, that would necessarily clear up much that was still doubtful about the events of that tragic night.
Suddenly an idea flashed into his mind. Was the letter genuine? He had never seen the butler’s hand-writing, and therefore could form no opinion from its appearance. But was the whole thing likely? Could it possibly be the work of Boirac? Might not the manufacturer have discovered that he, La Touche, was on his trail, and might not this be a trap? Could it be an attempt to lure him into a house in which he and his information would be at the manufacturer’s mercy?
This was a sinister idea, and he sat pondering its possibility for some minutes. On the whole, he was disposed to reject it. Any attempt on his life or liberty would be exceedingly risky for Boirac. If he really knew what had come out, his game would surely be to collect what money he could and disappear while there was yet time. All the same La Touche felt he should neglect no precaution for his own safety.
He went to the telephone and called up the house in the Avenue de l’Alma.
‘Is M. Fran?ois there?’ he asked, when he had got through.
‘No, monsieur,’ was the reply. ‘He has gone out for the afternoon. He will be in about 7.30.’
‘Thank you. Who is speaking, please?’
‘Jules, monsieur, the footman. I am in charge till M. Fran?ois returns.’
This was unsatisfactory, but quite natural and unsuspicious. La Touche felt fairly satisfied, and yet, almost against his will, a doubt remained. He thought he might be better with company, and made another call.
‘That you, Mallet? Which of you is off duty? You? Well, I want your company to-night on a short excursion. Will you call round for dinner here at seven and we can go on afterwards?’
When Mallet arrived, La Touche showed him the letter. The subordinate took precisely the same view as his chief.
‘I don’t think it’s a plant,’ he said, ‘but with Boirac you can’t be too careful. I should bring your John Cockerill, or whatever you use, if I were you.’
‘I’ll do so,’ said the other, slipping an automatic pistol into his pocket.
They reached the house in the Avenue de l’Alma about 8.15, and La Touche rang. To their surprise and disappointment the door was opened by no less a person than Boirac himself. He seemed to be on the point of going out, as he wore his hat and a dark, caped overcoat which, open at the front, showed his evening dress. Round his right hand was tied a blood-stained handkerchief. He appeared annoyed and as if his temper might give way at any minute. He looked inquiringly at the detectives.
‘Could we see M. Fran?ois, monsieur,’ asked La Touche politely.
‘If you don’t mind waiting a few minutes, certainly,’ answered Boirac. ‘I was just going out when I cut my hand and I had to send him for a doctor to stop the bleeding. He will be back in a moment. If you like to wait, you can do so in his room—the fourth door on the right.’
La Touche hesitated a moment. What if it was a plant after all? Finding Boirac here alone was certainly suspicious. But the cut at least was genuine. La Touche could see the red stain slowly spreading across the handkerchief.
‘Well, messieurs, I’m sorry I can’t hold the door open. Kindly either come in and wait, or, if you prefer it, call back later on.’
La Touche made up his mind. They were armed and on their guard. As he entered the hall his left hand in his overcoat pocket crept to the handle of his magazine pistol, and he quietly covered the manufacturer.
The latter closed the front door behind them and led the way to Fran?ois’s room. It was in darkness, but Boirac, entering before the others, turned on the light.
‘Come in and be seated, gentlemen, if you please,’ he said. ‘I should like a word with you before Fran?ois returns.’
La Touche did not at all like the turn affairs were taking. Boirac’s conduct seemed to him to grow more and more suspicious. Then he reflected again that they were two to one, were armed, and keenly on their guard, and that there could be no cause for uneasiness. Besides, there could be no trap. Boirac had preceded them into the room.
The manufacturer pulled together three chairs.
‘If you would kindly be seated, gentlemen, I would tell you what I want you to know.’
The detectives obeyed, La Touche still keeping his pistol turned on his host.
‘Gentlemen,’ went on the latter, ‘I owe you both a very full apology for having played a trick on you, but I am sure, when I have explained the extraordinary circumstances in which I am placed, you will hold me, if not justified, at least excused. And first, I must tell you that I know who you are, and on what business you came to Paris.’
He paused for a moment. Then, the others not replying, he continued:—
‘I happened to notice your advertisement, M. La Touche, for Mlle. Lambert, and it set me thinking. And when I found, M. Mallet, that you and your friend were shadowing me, I thought still more. As a result of my cogitations I employed a private detective, and learnt from him the identity of both of you and what you were engaged on. When I learnt that you had found Mlle. Lambert, I guessed you would soon discover the typewriter, and sure enough, my detective soon after reported that you had purchased a second-hand No. 7 Remington. Then I had the carter, Dubois, shadowed, and I thus learnt that you had discovered him also. I have to compliment you, M. La Touche, on the cleverness with which you found out these matters.’
Again he paused, looking inquiringly and somewhat hesitatingly at the others.
‘Pray proceed, M. Boirac,’ said La Touche at last.
‘First, then, I offer you my apologies for the trick played you. I wrote the note which brought you here. I feared if I wrote in my own name you would suspect some trick on my part and refuse to come.’
‘Not unnaturally a suspicion of the kind did enter our minds,’ answered La Touche. ‘It is but fair to tell you, M. Boirac, that we are armed’—La Touche withdrew his automatic pistol from his pocket and laid it on a table at his hand—‘and if you give either of us the slightest cause for anxiety, we shall fire without waiting to make inquiries.’
The manufacturer smiled bitterly.
‘I am not surprised at your suspicions. They are reasonable, though absolutely unfounded, and your precautions cannot therefore be offensive to me. As I try to do everything thoroughly, I may admit this cut on my hand was also faked. I simply squeezed a tube of liquid red paint on to the handkerchief. I did it to account for my being alone in the hall when you arrived, which I thought necessary, lest you might refuse to enter.’
La Touche nodded.
‘Pray proceed with your statement,’ he said again.
For a man of his years, Boirac looked strangely old and worn. His black hair was flecked with white, his face drawn and unhappy and his eyes weary and sombre. Though he had been speaking quietly enough, he seemed deeply moved and at a loss how to proceed. At last, with a gesture of despair, he went on:—
‘What I have to say is not easy, but, alas, I deserve that. I may tell you at once without any beating about the bush—I brought you here to-night to make my confession. Yes, gentlemen, you see before you the miserable, guilty man. I killed her, gentlemen. I did it that awful night of the dinner party. And since then I have never known one moment’s ease. What I have suffered no living being could describe. I have been in hell ever since. I have aged more in these last few weeks than in ten years of ordinary life. And now, when to the gnawings of remorse the certainty of the result of your researches is looming before me—I can bear it no longer. The suspense must end. Therefore, after much thought I have decided to make my confession.’
That the man was in earnest and his emotion genuine La Touche could no longer doubt. But his suspicions still remained. He asked a question.
‘Why have you brought us here to tell us, M. Boirac? Surely the obvious thing would have been for you to go to the S?reté and see M. Chauvet.’
‘I know. I should have done that. But this was easier. I tell you, gentlemen, it is bad enough to have to say this to you here, sitting quietly in my own house. There—with several and perhaps stupid officials, with typists—I just couldn’t face it. What I want you to do is this: I will tell you everything. Any questions you ask I will answer. Then I don’t want to be bothered with it again. All I now hope for is that the end will come quickly. You do what is necessary and at the trial I will plead guilty. You will agree?’
‘We will hear what you have to say.’
‘For that, at least, I am grateful.’ He pulled himself together with an obvious effort and continued in a low tone, without showing very evident traces of emotion.
‘My statement, I fear, will be a long one, as I must tell you all that occurred from the beginning, so that you may understand what led up to this awful consummation. A great part of it you already know—how my wife and Felix fell in love at the art school, and how her father refused his consent to their marriage, then how I, too, fell a victim and asked her hand; how my suit was looked upon with favour and I was misled both by herself and her father about what had taken place at the art school, and how, in short, we were married. And you know, too, I imagine, that our marriage from the first was a failure. I loved Annette intensely, but she never cared for me. We needn’t go into it, but I soon saw that she had only married me in a fit of despair at her engagement being broken off. She did me the gravest wrong, though I admit I don’t think she meant or realised it. We drifted farther and farther apart, till life together became insupportable. And then I met Felix and asked him to the house, not knowing till weeks later that he was the man who had been in love with my wife at the art school. But you must not think I have anything to say against the honour of either of them. My wife spoiled my life it is true, but she did not elope with Felix, nor did he, so far as I know, ask her to. They were good friends, but, to the best of my belief, nothing more. That is the smallest and the only reparation I can make them, and I make it unreservedly.
‘But with me, alas, it was different. Balked of any chance of happiness in my home through my wife’s wicked action—I say it advisedly—her wicked action in marrying me while she loved another, I succumbed to the temptation to look elsewhere for happiness. I met, quite by accident, some one with whom I could have been happy. You will never learn who she was or how I managed to meet her without being suspected—it is enough to say that things reached such a pass that this woman and I found we could no longer go on in the way we were, meeting by stealth, seeing each other only with carefully thought-out precautions. The situation was intolerable and I determined to end it. And it was on the evening of the dinner party that I first saw the way.
‘But here, before I go on to tell you the events of that terrible night, lest you might try to find this woman and saddle her with a part of the responsibility for what followed, let me tell you that here again I lost. The week after I destroyed my soul with the ghastly crime of which I will tell you, she got a chill. It turned to pneumonia, and in four days she was dead. I saw the judgment of Heaven beginning. But that is for me alone. Her name, at any rate, is safe. You will never find it out.’
Boirac’s voice had fallen still lower. He spoke in a sort of toneless, numb way, as if mechanically, and yet his hearers could see that only his iron control prevented a breakdown.
‘On that night of the dinner party,’ he resumed, ‘I met Felix accidentally in the hall on his arrival, and brought him into my study to see an etching. It is true we there spoke of the cask which had just arrived with my group, but I gave him no information such as would have enabled him to obtain a similar one.
‘All that has been found out of the events of that evening up to the time that I left the works is true. It is true I thought at first I would be kept till late, and afterwards got away comparatively early. I actually left the works about eleven, took the Metro and changed at Chatelet, as I said, but from there my statement to the police was false. No American friend clapped me on the back as I alighted there, nor did such a man exist at all. My walk with him to the Quai d’Orsay, our further stroll round the Place de la Concorde, his going by train to Orléans, and my walk home—all these were pure inventions on my part, made to account for my time between eleven-fifteen and one. What really happened during this time was as follows:
‘I changed at Chatelet, taking the Maillot train for Alma, and walked home down the Avenue. I must have reached my house about twenty minutes or a quarter to twelve.
‘I took out my latchkey as I mounted the steps, and then I noticed that one of the slats of the venetian blind of the drawing-room window looking out towards the porch had caught up at one end, and a long, thin, triangular block of light shone out into the night. It was just on the level of my eyes and involuntarily I glanced through. What I saw inside stiffened me suddenly and I stood looking. In an arm-chair in the farther part of the room sat my wife, and bending closely over her, with his back towards me, was Felix. They were alone, and, as I watched, a plan entered my mind, and I stood transfixed with my pulses throbbing. Was there something between my wife and Felix? And if not, would it not suit my purpose to assume there was? I continued looking in and presently Felix rose to his feet and they began talking earnestly, Felix gesticulating freely, as was his habit. Then my wife left the room, returning in a few moments and handing him a small object. I was too far off to see what it was, but it seemed like a roll of banknotes. Felix put it carefully in his pocket and then they turned and walked towards the hall. In a few seconds the door opened and I shrank down into the shadows below the window sill.
‘“Oh, Léon,” I heard my wife’s voice, and it seemed charged with emotion. “Oh, Léon, how good you are! How glad I am you have been able to do this!”
‘Felix’s voice showed that he also was moved.
‘“Dear lady, is not such happiness to me? You know I am always at your service.”
‘He moved down the steps.
‘“You’ll write?”
‘“Immediately,” he answered, and was gone.
‘As the door closed, a furious passion of hate burned up in me for this woman who had ruined my life—who had not only ruined it, but who was still blocking out any chance of happiness I might have had. And also I furiously and jealously hated Felix for being the cause, however innocent, of my loss. And then suddenly I felt as if—perhaps I should say I felt that—a devil had entered and taken possession of me. I became deadly cold and I had the strange feeling that I myself was not really there, but that I was watching some one else. I slipped out my key, noiselessly opened the door, and followed my wife into the drawing-room. Her calm, nonchalant walk across the room roused me to still wilder fury. How well I knew her every motion. This was the way she would have turned to greet me when I arrived from the works, with cold politeness—when it might have been so different. . . .
‘She reached her chair in the corner of the room and turned to sit down. As she did so she saw me. She gave a little scream.
‘“Raoul, how you startled me,” she cried. “Have you just arrived?”
‘I threw off my hat and she saw my face.
‘“Raoul,” she cried again, “what’s the matter? Why do you look like that?”
‘I stood and looked at her. Outwardly I was calm, inwardly my blood whirled like molten metal through my veins and my mind was a seething fire.
‘“Nothing really,” I said, and some one else seemed to be speaking in a voice I had never heard before, a hoarse, horrible voice. “Only a mere trifle. Only Madame entertaining her lover after her husband has come home.”
‘She staggered back as if from a blow and collapsed into her chair, and turned her now pallid face to me.
‘“Oh!” she cried in a trembling, choking voice. “Raoul, it’s not true! It’s not true, Raoul, I swear it! Don’t you believe me, Raoul?”
‘I stepped close to her. My hate swelled up in a blinding, numbing, overwhelming passion. It must have shown in my eyes, for a sudden fear leapt into hers.
‘She tried to scream, but her dry throat produced only a piteous little cry. Her face had grown ghastly. Drops of sweat grew on her brow.
‘I was close by her now. Instinctively my hands went out. I seemed to feel her slender neck between them, with my thumbs pressing. . . . She read my purpose, for a hideous terror shone in her eyes. Dimly I was conscious of her hands tearing at my face. . . .
‘I stopped. My brain was numb. I seemed to see myself from a great distance standing looking at her. She was dead. I hated her more than ever. I was glad to see her dead, to watch that horror still lingering in her eyes. And he? How I hated him, he who had lost me my love and spoilt my life. I would go now. I would follow him and I would kill him. Kill him as I had killed her. I stumbled blindly to find the door.
‘And then the devil that possessed me suggested another plan. He had wanted her. Well, he would get her. If he couldn’t have her alive, he could have the next best thing. He could have her dead.’
M. Boirac paused. He had been speaking in a high-pitched voice and gesticulating as if overwhelmed with excitement. He seemed unconscious of his hearers, as if, carried away by his recollections, he was mentally living over again the awful scene, passing once more through the frenzy of that terrible time. Then after a few moments’ silence he pulled himself together and went on in a more normal tone.
‘I determined t............