As they reached the library again a small silver clock on the mantelpiece gave a single chime. Merrington looked at it, and then glanced at his watch.

"Half-past eight!" he said. "That clock is five minutes slow—by me. The people who have been staying here will go off after breakfast. Visitors always leave a house of trouble as soon as possible—like rats deserting a sinking ship. The thing is to question as many as we can get hold of before they go. As some of them knew Mrs. Heredith before her marriage, we may elicit something about her or her antecedents which will throw some light on the motive for the crime."

"I do not think Sir Philip will care to have his guests questioned," remarked Captain Stanhill doubtfully. "They must be all well-connected and very respectable people, or they would not have been invited here."

"There have been very respectable and highly connected murderers before to-day, Captain Stanhill, as no doubt you are aware," rejoined Merrington caustically.

"The guests were all downstairs in the dining-room at the time the murder was committed," said Caldew. "Miss Heredith told me so herself."

"I am aware of that fact also," retorted Merrington sharply. "Nevertheless, they must be seen. We cannot afford to throw away a chance."

"It is a delicate and awkward business," murmured the Chief Constable.

"It will be a delicate and awkward business for us if we don't lay our hands on this criminal," responded Merrington. "Sir Philip Heredith, with his influence and connections, will be able to make it pretty hot for Scotland Yard and the County Police if the murderer of his son's wife is allowed to escape. You'd better take the job in hand at once, Caldew. Weyling can go with you and help. See as many of the guests as you can—especially the ladies—and get what you can out of them. But I'd be glad if you'd first ask Miss Heredith to grant me an interview before breakfast. Don't send a servant, but see her yourself."

Caldew left the room to undertake the investigations allotted to him, and Weyling followed him with a startled expression of face. He felt overweighted by the magnitude of the task which had been thrust upon him, and doubted his ability to discharge it properly.

"Miss Heredith will be able to give us more information than Sir Philip," remarked Merrington in a friendly tone to Captain Stanhill, as the door closed behind the subordinate officials. "A woman is generally more observant than a man—particularly if anything underhand has been going on."

Captain Stanhill cast a puzzled glance at his companion. As a simple-minded English gentleman he was quite unable to penetrate the obscurity of expression which masked the meaning of the last remark. Merrington caught the look, but had formed too poor an opinion of his companion's understanding to explain himself further. Besides, he liked mystifying people.

"I'm going to put the servants through their facings straight away," he continued. "If there is anything to be learnt we are more likely to find it out from them than the guests. Trust the backstairs for knowing what's going on upstairs! Servants want skilful handling, though. You've got to know when to bully and when to coax. Half measures are no good with them."

Captain Stanhill did not reply. He wandered round the spacious library, glancing at the rows of books in their oaken shelves. Superintendent Merrington, while awaiting the arrival of Miss Heredith, drew forth the plan of the moat-house which Caldew had sketched, and studied it closely.

The moat-house had only two stories, but it was a rambling old place and covered a considerable area of ground, facing three sides of the county. The principal portion, consisting of the old house which had been burnt down and rebuilt, faced the north. The two wings had been added later.

The front door opened into a spacious entrance hall which in former times had been the dining-room. At the end of the hall was the grand staircase, adorned by statues, armour, and the Heredith arms carved in panels. The principal rooms, with the exception of the dining-room, were all on the ground floor of the main building, but corridors led off the entrance hall to the newer wings at each side, extending on the right side to the billiard room, conservatory, greenhouses, and orangery, and on the left side to the dining-room, Miss Heredith's private sitting-room, and Sir Philip's study.

Merrington carefully studied the arrangements of this wing, as depicted on Caldew's sketch plan. The upper portion was reached by a staircase which opened off the corridor almost opposite the dining-room door, and ran, with one turning, to a landing which was only a few feet away from the door of the bedroom in which Mrs. Heredith was murdered. Next to this room was a dressing-room, and a spare bedroom. The remainder of the wing consisted of two bathrooms, a linen room, and Miss Heredith's bedroom, which was at the south end of the wing. The rooms all faced the west side of the house, and were lit by windows opening on the terraced gardens. They were entered by a corridor which ran the whole length of the wing, terminating in the door which opened on the unused back staircase.

Before Merrington had finished his scrutiny of the plan, the door opened, and Miss Heredith entered the library. She looked pale and worn, and there were dark rings under her eyes which suggested a sleepless night. But her face was composed, though grave.

Captain Stanhill advanced and shook hands with her, uttering a few words of well-bred sympathy as he did so, and then introduced Superintendent Merrington.

"Superintendent Merrington has been kind enough to come down from Scotland Yard at my request to give us the benefit of his skill in investigating this terrible crime," he said simply.

"I desired an interview with you in order to ask a few questions," said Merrington, coming to the point at once.

Miss Heredith bowed.

"Were all the blinds down in the dining-room last night during dinner?" asked Merrington.

Captain Stanhill looked quickly at his colleague. He failed to see the purpose of the question.

"I think so," replied Miss Heredith, after a moment's reflection. "I cannot say for certain, as I was out of the room during the latter portion of the dinner, but I can easily ascertain." She touched a bell, which was answered by a maidservant. "Tell Mr. Tufnell I wish to speak to him," she said.

The girl went away, and Tufnell appeared a moment afterwards.

"Were the blinds all drawn in the dining-room during dinner last night, Tufnell?"

"Yes, ma'am. I pulled them down myself before sounding the gong."

"Thank you, Tufnell."

"I understand that you were not present at the dinner table when the shot was fired?" said Merrington when the butler had left the room.

"No, I was not."

"May I ask why you left the table?"

The question was put suavely enough, but a half-uttered protest from Captain Stanhill indicated that he, at least, realized the sting contained within it. But Miss Heredith, looking at Merrington with her clear grey eyes, replied calmly:

"I was called out of the room to speak to our chauffeur. He had been ordered to have an extra vehicle in readiness to convey our guests to an evening entertainment, and he wished to consult me about it."

"Why did you not return to the dining-room?"

"Because dinner was nearly finished when I left the room."

"Where were you when the shot was fired?"

"I was on the stairs, on the way to my room when I heard the scream. I was hastening back to the dining-room as quickly as possible, but before I reached it the shot rang out."

"Surely these questions are unnecessary, Merrington," exclaimed Captain Stanhill. "Anyone would think—I mean that there is not the slightest idea in our minds that Miss Heredith—at least, I meant to say—" Captain Stanhill floundered badly as he realized that his remarks were capable of a terrible interpretation which he did not intend, and broke off abruptly.

"I am very glad that Superintendent Merrington has asked these questions," said Miss Heredith coldly.

Merrington bowed a grim acknowledgment. He had still many questions he wanted to ask Miss Heredith, and he proceeded to put them in his own masterful way, very much as though he were examining a witness in the police court, Captain Stanhill thought, but in reality with a courtesy and consideration quite unusual for him. It was his best manner; his worst, Captain Stanhill was to see later. As a matter of fact, it was impossible for Merrington to be gentle with anybody. He had spent so many years of his life probing into strange stories and sinister mysteries that he had insensibly come to regard the world as a larger criminal court, made up of tainted and adverse witnesses, whom it was his privilege to cross-question.

He questioned Miss Heredith searchingly about the young bride. According to an eminent expert in jurisprudence, the tendency to believe the testimony of others is an inherent instinct implanted in the human breast by the Almighty. If that be so, it is to be feared that the seed had failed to germinate in Merrington's bosom, for his natural tendency was to look upon his fellow creatures as liars, particularly when they were of good social standing, with that hatred of notoriety which is characteristic of their class. Merrington had this fact in his mind as he interrogated Miss Heredith closely about the circumstances of her nephew's marriage. He hoped to extract from her something which her English pride might lead her to conceal, something which might throw a light on the motive for the murder.

Miss Heredith answered him with a frankness which even Merrington grudgingly realized left nothing to be desired. She was, apparently, only too anxious to help the police investigations to the best of her ability. But what she had to tell amounted to very little. Her first knowledge of her nephew's intention to marry was contained in a letter written home some four months before, in which he announced his engagement to a young lady engaged in war work in a London Government office. A month later came the news that he was married, and was bringing his young bride to the moat-house. The young couple arrived a week after the receipt of the second letter. They were welcomed home, and settled down to country life in the old place. Phil left his post in the War Office, and busied himself in looking after the estate. He was very fond of his young wife, but it was obvious from the first that Violet found the quiet country existence rather dull after her London life. She knew nobody in Sussex except Mrs. Weyne, the author's wife, who had been an acquaintance of hers in London years before, and she did not seem to care much for the county people who visited the moat-house. She received letters from girl friends in London, and sometimes read extracts from them at the breakfast table, but her life, on the whole, was a secluded one. It was in order to brighten it that Phil suggested a house party. The guests consisted principally of Violet's and Phil's London friends and acquaintances.

"Do you know the names of these girl friends who used to write to her?" asked Merrington.

Miss Heredith replied that she did not.

"I suppose her husband would know them?"

"It is quite impossible to question my nephew," said Miss Heredith decisively. "He is dreadfully ill."

Merrington nodded in a dissatisfied sort of way. He was aware of Phil's illness, and his suspicious mind wondered whether it had been assumed for the occasion in order to keep back something which the police ought to know. His thick lip curled savagely at the idea. If these people tried to hide anything from him in order to save a scandal, so much the worse for them. But that was something he would go into later.

The next questions he put to Miss Heredith were designed to ascertain what she thought of the murder, whether she had any suspicions of her own, and whether there was any reason for suspecting Miss Heredith herself. At that stage of the inquiry it was Merrington's business to suspect everybody. He could not afford to allow the slightest chance to slip. His object was to get at the truth; to weigh each particle of supposition or evidence without regard to the feelings or social position of the witness.

The case so far puzzled him, and Miss Heredith's answers to his questions revealed little about the murder that he had not previously known. The only additional facts he gleaned related to the murdered girl's brief existence at the moat-house; of her earlier history and her London life Miss Heredith knew nothing whatever. Merrington made some notes of the replies in an imposing pocket-book, but he was plainly dissatisfied as he turned to another phase of the investigation.

"Were all your guests in the dining-room at the time the scream and the shot were heard?" he asked.

"They were all there when I left the room. The butler can tell you if any left afterwards."

"I will question Tufnell on that point later. No, on second thoughts, it will be better to settle it now. I attach importance to it."

Tufnell was recalled to the room, and, in reply to Superintendent Merrington's question, stated that none of the guests left the dining-room before the shot was fired. Tufnell added they were all interested in listening to a story that Mr. Musard was telling. Having imparted this information the butler returned to the breakfast room, overweighted with the responsibility of superintending the morning meal in his mistress's absence.

"Is this Musard the jewel expert of that name?" asked Merrington.

"Our guest is Mr. Vincent Musard, the explorer," replied Miss Heredith coldly.

"The same man." Merrington made another minute note in his pocket-book, and continued, "May I take it, then, that all your guests who were staying here were assembled in the dining-room at the time the murder was committed?"

"Yes; except one who left during the afternoon."

"Who was that?"

"Captain Nepcote, a friend of my nephew's. He received a telegram recalling him to the front, and returned to London by the afternoon train."

Merrington made a note of this in his pocket-book with an air of finality, and asked Miss Heredith to see that the servants were sent to the library one by one, to be questioned. Miss Heredith said she would arrange it with the housekeeper, and was then politely escorted to the door by Captain Stanhill.

The next few hours were educative for Captain Stanhill. Although he was Chief Constable of Sussex, he took no part in the proceedings, but sat at the table like a man in a dream, living in a world of Superintendent Merrington's creation—a world of sinister imaginings and vile motives, through which stealthy suspicion prowled craftily with padded feet, seeking a victim among the procession of weeping maids, stolid under-gardeners, stable hands, and anxious upper servants who presented themselves in the library to be questioned. But it seemed to Captain Stanhill that though the women were flustered and the men nervous, they knew nothing whatever about the atrocious murder which had been committed a few hours before in the room above their heads. Merrington also seemed to be aware that he was getting no nearer the truth with his traps, his questions, and his bullying, and he grew so angry and savage as the day wore on that he reminded Captain Stanhill of a bull he had once seen trying to rend a way through a mesh. As the morning advanced, Merrington's face took on a deeper tint of purple, his fierce little eyes grew more bloodshot, and between the intervals of examining the servants he mopped his perspiring head with a large handkerchief.

The significance of one fact he did not realize until afterwards. The last of the inmates of the moat-house to come to the library was the housekeeper, Mrs. Rath, who presented herself at his request in order to acquaint him with the details of the domestic management of the household. Mrs. Rath entered the room with a nervous air. Her white face contrasted oddly with her black dress, and her hands shook slightly, in spite of her effort to appear composed. Merrington stared at her careworn face and hollow grey eyes with the perplexed sensation of a man who is confronted with a face familiar to him, but is unable to recall its identity.

"Where have I seen you before?" he blurted out.

The housekeeper raised frightened eyes, ringed with black, to his truculent face, but dropped them again without speaking. Merrington did not repeat his question. He did not imagine the housekeeper knew anything about the murder, but it was a mistake to put a witness on her guard. It was in quite a different tone that he thanked Mrs. Rath for sending the servants to the library, and asked her to describe the household arrangements of the previous night. Mrs. Rath, who had been palpably nervous after his first question, became reassured and more at her ease, and answered him intelligently.

"And where were you at the time of the murder, Mrs. Rath?" pursued Merrington, when he had drawn forth these details.

"I was in my sitting-room."

"Did you hear the scream and the shot?"

"I heard the scream, but not the shot."

"How was that?"

"My sitting-room is a long way from Mrs. Heredith's room. Perhaps that is the reason."

Merrington looked at the position of the housekeeper's room on the plan of the moat-house which Caldew had drawn. As she said, it was a considerable distance to her room, which was in the old portion of the house, near the rear, and on the ground floor.

"Were you alone in your room?" he asked.

"No. My daughter was sitting with me."

To a quick ear it may have seemed that the answer was a trifle long in coming.

Merrington shook his head irritably. Really, it seemed impossible to reach the end of the people who were in this infernal moat-house at the time of the murder.

"Does your daughter live with you here?" he asked.

"Oh, no. She came to see me yesterday afternoon, and stayed all night because she missed her train back after—after the tragedy."

"Is she here now?"

"No. She went away by an early train. She is employed as a milliner at Stading, the market town, which is ten miles away."

"She lives there, I suppose?"

"Yes. She lives in."

"Who is her employer?"

"Mr. Closeby, the draper. Daniel Closeby and Son is the name of the firm."

Merrington made another note in his pocket-book. It sounded plausible enough, but the girl must be added to the lengthening list of people in the case who would have to be seen.

"I think that is all I need detain you for, Mrs. Rath," he said.

The housekeeper lingered to inquire when the gentlemen would like their lunch. Merrington, who had breakfasted early and passed an arduous morning, replied bluntly that it could not be too soon to please him.

"I'll have it served in the small breakfast-room in a quarter of an hour," said Mrs. Rath, hurrying away.

Her whole bearing, as she departed, indicated such an air of irrepressible relief at having passed through a trying ordeal that all Merrington's former doubts of her revived.

"I'd give something to remember where I've seen that infernal woman before," he ejaculated, slapping his thigh emphatically.

"What infernal woman?" asked Captain Stanhill, who had come to the conclusion that he did not like Superintendent Merrington or his style of conversation.

"Why, that woman who has just left the room—that housekeeper. I've seen her before somewhere, in very different circumstances, but I cannot recall where. I recollect her face distinctly—particularly her eyes. I flatter myself I never forget a pair of eyes. Confound it, where the devil have I seen her?"

Captain Stanhill turned away indifferently, and the conversation was terminated by the appearance of Detective Caldew, who appeared in the doorway as Mrs. Rath left the room.

"Dr. Holmes is waiting in the drawing-room if you wish to see him," he announced.

"Bring him here," commanded Merrington curtly. He had a great notion of his self-importance, and had no intention of dancing attendance on a mere country practitioner.

Caldew went away, and shortly reappeared with a little man whom he introduced as Dr. Holmes. The doctor was a meagre shrimp of humanity, with a peevish expression on his withered little face, as though he were bored with his own nonentity. He was dressed in faded clothes and carried a small black bag in one hand and a worn hat in the other. If he had any idea of airing a professional protest at being compelled to wait upon the police, the thought vanished as his eye took in the stupendous stature of Superintendent Merrington, who towered above him like a mastiff standing over a toy terrier.

"Sit down, doctor," he curtly commanded. "I want to ask you a few questions about the death of Mrs. Heredith. You examined the body, I understand?"

Dr. Holmes bowed, put on a pair of gold-rimmed spectacles in order to see Superintendent Merrington better, and waited to be questioned.

"I understand you were summoned to the moat-house last night, doctor, after Mrs. Heredith was murdered, and examined the body. What was the cause of death?"

"The cause of death was a bullet wound," pronounced the doctor oracularly.

"I am aware of that much," answered Merrington irritably. "But a bullet wound is not necessarily fatal. Mrs. Heredith lived some time after her death, so it is certain that the bullet which killed her did not penetrate the heart. What is the nature of the injuries it inflicted?"

"Death in Mrs. Heredith's case was the result of a bullet passing through the left lung. It passed between the second and third ribs in entering the body, traversed the lung, causing a great flow of blood, which filled the air passages."

"Then the cause of death was hÆmorrhage?"

"Yes. There was very severe internal hÆmorrhage. The face and the left-hand side of the neck were covered with blood. There had also been bleeding from the mouth and nose. Mr. Musard, who accompanied me to the room, told me he had washed it away while Mrs. Heredith was dying, in an endeavour to staunch the flow."

"She was quite dead when you saw her?"

"Oh, yes. Judging by the warmth of the body, and by the fact that blood had ceased to flow, I should say that death had taken place about forty minutes before."

"What time did you reach the moat-house?"

"It would be about twenty minutes past eight. Sergeant Lumbe called at my house at ten minutes past the hour—I made a note of the time—and I went immediately. It is about ten minutes' walk to the moat-house from the village."

"Was the main blood vessel of the lung broken?" asked Captain Stanhill, who had been following the doctor's remarks with close attention.

"The aorta? It is difficult to say from an external examination. Mr. Musard tells me that Mrs. Heredith died about five minutes after he reached the room. The aorta is a very large vessel, and if it were burst bleeding to death would be very rapid."

"Could the wound have been self-inflicted?" asked Merrington.

Dr. Holmes pursed his lips.

"I can form no definite opinion on that point," he said. "By the direction of the bullet, I should say not."

"Have you found the bullet?"

"No, it is in the body. As apparently it took a course towards the right after entering the body, and there is no corresponding wound in the back, I should say that it is lodged somewhere in the vertical column. Of course, I cannot be sure."

"The Government pathologist will clear up these points when he makes the post-mortem examination," said Merrington. "I do not think we have any more questions to ask you, doctor."

"How is your patient, the young husband?" asked Captain Stanhill, as Dr. Holmes rose.

"The symptoms point to brain fever. The family, on my advice, have sent to London for Sir Ralph Horton, the eminent brain doctor."

"I do not wonder his mind has given way under the shock," remarked Captain Stanhill. "To lose his wife in such terrible circumstances after three months' marriage must have been a cruel blow."

"It was the worse in his case because he has always been nervous and highly strung from childhood—partly, I think, as the result of his infirmity. He has a deformed foot. His present illness seems to be a complete overthrow of the nervous system. I have been with him the greater part of the night. He has been highly delirious, but he is a little quieter now."

Merrington pricked up his ears at this last remark. After his fruitless investigations of the morning he was inclined to think that the clue to the murder lay in the past—it might be in some former folly or secret intrigue of the young wife's single days. The question was, in that case, whether the husband was likely to have any knowledge of his wife's secret. If he had, he might, in his delirium, babble something which would provide a clue to trace the murderer. It was a poor chance, but the poorest chance was worth trying in such a baffling case.

"I should like to have a look at your patient," he said to Dr. Holmes.

"It would be impossible to question him in his present state," replied the doctor stiffly.

"I do not wish to question him. I merely wish to look at him."

"In that case you may see him. He is quite unconscious, and recognizes nobody. I will take you to his room, if you wish."

The little doctor bustled along the corridor, and turned into a passage traversing the right wing of the moat-house. About half way down it he paused before a door, which he opened softly, and motioned to the other two to enter.

It was a single bedroom, panelled in oak, which was dark with age, with one small window; but it had the advantage of being as far away as possible from the upstairs bedroom in the left wing where Phil's wife lay murdered. A small fire burnt in the grate, a china bowl of autumn flowers bloomed on a table near the bedside, and a capable looking nurse was preparing a draught by the window. She glanced at the three men as they entered, but went on with her occupation.

The sick man lay on his back, breathing heavily. His black hair framed a face which was ghastly in its whiteness, and his upturned eyes, barely visible beneath the half-closed lids, seemed fixed and motionless.

"Any change, nurse?" the doctor asked.

"No change, sir."

But even as she spoke Phil's face changed in a manner which was wonderful in its suddenness. His features became contorted, as though a sword had been thrust through his vitals, and he struggled upright in his bed, with one shaking hand outstretched. His eyes, glaring with delirium, roved restlessly over the faces of the men at the foot of the bed.

"She's dead, I tell you! Violet's dead.... Have they found him? Ah, who's that?"

Once again he uttered his young wife's name, and fell back on the pillow, motionless as before, but with one arm athwart his face, as though to cover his eyes.

"I shall be glad if you will leave the room," said the little doctor gravely. "Your presence excites him." He hurried round to the bedside and bent over his patient.