“Now for the events at Lachine between nine and ten on the evening of last Monday.”

“Mrs. Barclay was, it appears, a member of the Roman Catholic Church, and had interested herself very much in the establishment of the Guild of St. George, which was formed in connection with the Watt Street Chapel for the purpose of supplying the poor with cast-off clothing. A meeting of the Guild had been held that evening at eight, and Mrs. Barclay had hurried over her dinner in order to be present at it. When leaving the house she was heard by the coachman to make some commonplace remark to her husband, and to assure him that she would be back before very long. She then called for Miss Morrison, a young lady who lives in the next villa, and the two went off together to their meeting. It lasted forty minutes, and at a quarter-past nine Mrs. Barclay returned home, having left Miss Morrison at her door as she passed.

“There is a room which is used as a morning-room at Lachine. This faces the road and opens by a large glass folding-door on to the lawn. The lawn is thirty yards across, and is only divided from the highway by a low wall with an iron rail above it. It was into this room that Mrs. Barclay went upon her return. The blinds were not down, for the room was seldom used in the evening, but Mrs. Barclay herself lit the lamp and then rang the bell, asking Jane Stewart, the house-maid, to bring her a cup of tea, which was quite contrary to her usual habits. The Colonel had been sitting in the dining-room, but hearing that his wife had returned he joined her in the morning-room. The coachman saw him cross the hall and enter it. He was never seen again alive.

“The tea which had been ordered was brought up at the end of ten minutes; but the maid, as she approached the door, was surprised to hear the voices of her master and mistress in furious altercation. She knocked without receiving any answer, and even turned the handle, but only to find that the door was locked upon the inside. Naturally enough she ran down to tell the cook, and the two women with the coachman came up into the hall and listened to the dispute which was still raging. They all agreed that only two voices were to be heard, those of Barclay and of his wife. Barclay’s remarks were subdued and abrupt, so that none of them were audible to the listeners. The lady’s, on the other hand, were most bitter, and when she raised her voice could be plainly heard. ‘You coward!’ she repeated over and over again. ‘What can be done now? What can be done now? Give me back my life. I will never so much as breathe the same air with you again! You coward! You Coward!’ Those were scraps of her conversation, ending in a sudden dreadful cry in the man’s voice, with a crash, and a piercing scream from the woman. Convinced that some tragedy had occurred, the coachman rushed to the door and strove to force it, while scream after scream issued from within. He was unable, however, to make his way in, and the maids were too distracted with fear to be of any assistance to him. A sudden thought struck him, however, and he ran through the hall door and round to the lawn upon which the long French windows open. One side of the window was open, which I understand was quite usual in the summer-time, and he passed without difficulty into the room. His mistress had ceased to scream and was stretched insensible upon a couch, while with his feet tilted over the side of an arm-chair, and his head upon the ground near the corner of the fender, was lying the unfortunate soldier stone dead in a pool of his own blood.

“Naturally, the coachman’s first thought, on finding that he could do nothing for his master, was to open the door. But here an unexpected and singular difficulty presented itself. The key was not in the inner side of the door, nor could he find it anywhere in the room. He went out again, therefore, through the window, and having obtained the help of a policeman and of a medical man, he returned. The lady, against whom naturally the strongest suspicion rested, was removed to her room, still in a state of insensibility. The Colonel’s body was then placed upon the sofa, and a careful examination made of the scene of the tragedy.

“The injury from which the unfortunate veteran was suffering was found to be a jagged cut some two inches long at the back part of his head, which had evidently been caused by a violent blow from a blunt weapon. Nor was it difficult to guess what that weapon may have been. Upon the floor, close to the body, was lying a singular club of hard carved wood with a bone handle. The Colonel possessed a varied collection of weapons brought from the different countries in which he had fought, and it is conjectured by the police that his club was among his trophies. The servants deny having seen it before, but among the numerous curiosities in the house it is possible that it may have been overlooked. Nothing else of importance was discovered in the room by the police, save the inexplicable fact that neither upon Mrs. Barclay’s person nor upon that of the victim nor in any part of the room was the missing key to be found. The door had eventually to be opened by a locksmith from Aldershot.

“That was the state of things, Watson, when upon the Tuesday morning I, at the request of Major Murphy, went down to Aldershot to supplement the efforts of the police. I think that you will acknowledge that the problem was already one of interest, but my observations soon made me realize that it was in truth much more extraordinary than would at first sight appear.

“Before examining the room I cross-questioned the servants, but only succeeded in eliciting the facts which I have already stated. One other detail of interest was remembered by Jane Stewart, the housemaid. You will remember that on hearing the sound of the quarrel she descended and returned with the other servants. On that first occasion, when she was alone, she says that the voices of her master and mistress were sunk so low that she could hear hardly anything, and judged by their tones rather than their words that they had fallen out. On my pressing her, however, she remembered that she heard the word David uttered twice by the lady. The point is of the utmost importance as guiding us towards the reason of the sudden quarrel. The Colonel’s name, you remember, was James.

“There was one thing in the case which had made the deepest impression both upon the servants and the police. This was the contortion of the Colonel’s face. It had set, according to their account, into the most dreadful expression of fear and horror which a human countenance is capable of assuming. More than one person fainted at the mere sight of him, so terrible was the effect. It was quite certain that he had foreseen his fate, and that it had caused him the utmost horror. This, of course, fitted in well enough with the police theory, if the Colonel could have seen his wife making a murderous attack upon him. Nor was the fact of the wound being on the back of his head a fatal objection to this, as he might have turned to avoid the blow. No information could be got from the lady herself, who was temporarily insane from an acute attack of brain-fever.

“From the police I learned that Miss Morrison, who you remember went out that evening with Mrs. Barclay, denied having any knowledge of what it was which had caused the ill-humor in which her companion had returned.

“Having gathered these facts, Watson, I smoked several pipes over them, trying to separate those which were crucial from others which were merely incidental. There could be no question that the most distinctive and suggestive point in the case was the singular disappearance of the door-key. A most careful search had failed to discover it in the room. Therefore it must have been taken from it. But neither the Colonel nor the Colonel’s wife could have taken it. That was perfectly clear. Therefore a third person must have entered the room. And that third person could only have come in through the window. It seemed to me that a careful examination of the room and the lawn might possibly reveal some traces of this mysterious individual. You know my methods, Watson. There was not one of them which I did not apply to the inquiry. And it ended by my discovering traces, but very different ones from those which I had expected. There had been a man in the room, and he had crossed the lawn coming from the road. I was able to obtain five very clear impressions of his foot-marks: one in the roadway itself, at the point where he had climbed the low wall, two on the lawn, and two very faint ones upon the stained boards near the window where he had entered. He had apparently rushed across the lawn, for his toe-marks were much deeper than his heels. But it was not the man who surprised me. It was his companion.”