The Irishman’s pale face blackened with a new passion.

  “I have faced as many murderers in County Clare as you ever fought with in Clapham junction, Mr. Cockney,” he said.

  “Hush, please,” said Morton, sharply. “Wilson, you have no kind of right to imply doubt of your superior’s conduct. I hope you will prove yourself as courageous and trustworthy as he has always been.”

  The pale face of the red-haired man seemed a shade paler, but he was silent and composed, and Sir Walter went up to Nolan with marked courtesy, saying, “Shall we go outside now, and get this business done?”

  Dawn had lifted, leaving a wide chasm of white between a great gray cloud and the great gray moorland, beyond which the tower was outlined against the daybreak and the sea.

  Something in its plain and primitive shape vaguely suggested the dawn in the first days of the earth, in some prehistoric time when even the colors were hardly created, when there was only blank daylight between cloud and clay. These dead hues were relieved only by one spot of gold — the spark of the candle alight in the window of the lonely tower, and burning on into the broadening daylight. As the group of detectives, followed by a cordon of policemen, spread out into a crescent to cut off all escape, the light in the tower flashed as if it were moved for a moment, and then went out. They knew the man inside had realized the daylight and blown out his candle.

  “There are other windows, aren’t there?” asked Morton, “and a door, of course, somewhere round the corner? Only a round tower has no corners.”

  “Another example of my small suggestion,” observed Wilson, quietly. “That queer tower was the first thing I saw when I came to these parts; and I can tell you a little more about it — or, at any rate, the outside of it. There are four windows altogether, one a little way from this one, but just out of sight. Those are both on the ground floor, and so is the third on the other side, making a sort of triangle. But the fourth is just above the third, and I suppose it looks on an upper floor.”

  “It’s only a sort of loft, reached by a ladder, said Nolan. “I’ve played in the place when I was a child. It’s no more than an empty shell.” And his sad face grew sadder, thinking perhaps of the tragedy of his country and the part that he played in it.

  “The man must have got a table and chair, at any rate,” said Wilson, “but no doubt he could have got those from some cottage. If I might make a suggestion, sir, I think we ought to approach all the five entrances at once, so to speak. One of us should go to the door and one to each window; Macbride here has a ladder for the upper window.”

  Mr. Horne Fisher languidly turned to his distinguished relative and spoke for the first time.

  “I am rather a convert to the cockney school of psychology,” he said in an almost inaudible voice.

  The others seemed to feel the same influence in different ways, for the group began to break up in the manner indicated. Morton moved toward the window immediately in front of them, where the hidden outlaw had just snuffed the candle; Nolan, a little farther westward to the next window; while Wilson, followed by Macbride with the ladder, went round to the two windows at the back. Sir Walter Carey himself, followed by his secretary, began to walk round toward the only door, to demand admittance in a more regular fashion.

  “He will be armed, of course,” remarked Sir Walter, casually.

  “By all accounts,” replied Horne Fisher, “he can do more with a candlestick than most men with a pistol. But he is pretty sure to have the pistol, too.”

  Even as he spoke the question was answered with a tongue of thunder. Morton had just placed himself in front of the nearest window, his broad shoulders blocking the aperture. For an instant it was lit from within as with red fire, followed by a thundering throng of echoes. The square shoulders seemed to alter in shape, and the sturdy figure collapsed among the tall, rank grasses at the foot of the tower. A puff of smoke floated from the window like a little cloud. The two men behind rushed to the spot and raised him, but he was dead.

  Sir Walter straightened himself and called out something that was lost in another noise of firing; it was possible that the police were already avenging their comrade from the other side. Fisher had already raced round to the next window, and a new cry of astonishment from him brought his patron to the same spot. Nolan, the Irish policeman, had also fallen, sprawling all his great length in the grass, and it was red with his blood. He was still alive when they reached him, but there was death on his face, and he was only able to make a final gesture telling them that all was over; and, with a broken word and a heroic effort, motioning them on to where his other comrades were besieging the back of the tower. Stunned by these rapid and repeated shocks, the two men could only vaguely obey the gesture, and, finding their way to the other windows at the back, they discovered a scene equally startling, if less final and tragic. The other two officers were not dead or mortally wounded, but Macbride lay with a broken leg and his ladder on top of him, evidently thrown down from the top window of the tower; while Wilson lay on his face, quite still as if stunned, with his red head among the gray and silver of the sea holly. In him, however, the impotence was but momentary, for he began to move and rise as the others came round the tower.

  “My God! it’s like an explosion!” cried Sir Walter; and indeed it was the only word for this unearthly energy, by which one man had been able to deal death or destruction on three sides of the same small triangle at the same instant.

  Wilson had already scrambled to his feet and with splendid energy flew again at the window, revolver in hand. He fired twice into the opening and then disappeared in his own smoke; but the thud of his feet and the shock of a falling chair told them that the intrepid Londoner had managed at last to leap into the room. Then followed a curious silence; and Sir Walter, walking to the window through the thinning smoke, looked into the hollow shell of the ancient tower. Except for Wilson, staring around him, there was nobody there.

  The inside of the tower was a single empty room, with nothing but a plain wooden chair and a table on which were pens, ink and paper, and the candlestick. Halfway up the high wall there was a rude timber platform under the upper window, a small loft which was more like a large shelf. It was reached only by a ladder, and it seemed to be as bare as the bare walls. Wilson completed his survey of the place and then went and stared at the things on the table. Then he silently pointed with his lean forefinger at the open page of the large notebook. The writer had suddenly stopped writing, even in the middle of a word.

  “I said it was like an explosion,” said Sir Walter Carey at last. “And really the man himself seems to have suddenly exploded. But he has blown himself up somehow without touching the tower. He’s burst more like a bubble than a bomb.”

  “He has touched more valuable things than the tower,” said Wilson, gloomily.

  There was a long silence, and then Sir Walter said, seriously: “Well, Mr. Wilson, I am not a detective, and these unhappy happenings have left you in charge of that branch of the business. We all lament the cause of this, but I should like to say that I myself have the strongest confidence in your capacity for carrying on the work. What do you think we should do next?”

  Wilson seemed to rouse himself from his depression and acknowledged the speaker’s words with a warmer civility than he had hitherto shown to anybody. He called in a few of the police to assist in routing out the interior, leaving the rest to spread themselves in a search party outside.

  “I think,” he said, “the first thing is to make quite sure about the inside of this place, as it was hardly physically possible for him to have got outside. I suppose poor Nolan would have brought in his banshee and said it was supernaturally possible. But I’ve got no use for disembodied spirits when I’m dealing with facts. And the facts before me are an empty tower with a ladder, a chair, and a table.”

  “The spiritualists,” said Sir Walter, with a smile, “would say that spirits could find a great deal of use for a table.”

  “I dare say they could if the spirits were on the table — in a bottle,” replied Wilson, with a curl of his pale lip. “The people round here, when they’re all sodden up with Irish whisky, may believe in such things. I think they want a little education in this country.”

  Horne Fisher’s heavy eyelids fluttered in a faint attempt to rise, as if he were tempted to a lazy protest against the contemptuous tone of the investigator.

  “The Irish believe far too much in spirits to believe in spiritualism,” he murmured. “They know too much about ‘em. If you want a simple and childlike faith in any spirit that comes along you can get it in your favorite London.”

  “I don’t want to get it anywhere,” said Wilson, shortly. “I say I’m dealing with much simpler things than your simple faith, with a table and a chair and a ladder. Now what I want to say about them at the start is this. They are all three made roughly enough of plain wood. But the table and the chair are fairly new and comparatively clean. The ladder is covered with dust and there is a cobweb under the top rung of it. That means that he borrowed the first two quite recently from some cottage, as we supposed, but the ladder has been a long time in this rotten old dustbin. Probably it was part of the original furniture, an heirloom in this magnificent palace of the Irish kings.”

  Again Fisher looked at him under his eyelids, but seemed too sleepy to speak, and Wilson went on with his argument.

  “Now it’s quite clear that something very odd has just happened in this place. The chances are ten to one, it seems to me, that it had something specially to do with this place. Probably he came here because he could do it only here; it doesn’t seem very inviting otherwise. But the man knew it of old; they say it belonged to his family, so that altogether, I think, everything points to something in the construction of the tower itself.”

  “Your reasoning seems to me excellent,” said Sir Walter, who was listening attentively. “But what could it be?”

  “You see now what I mean about the ladder,” went on the detective; “it’s the only old piece of furniture here and the first thing that caught that cockney eye of mine. But there is something else. That loft up there is a sort of lumber room without any lumber. So far as I can see, it’s as empty as everything else; and, as things are, I don’t see the use of the ladder leading to it. It seems to me, as I can’t find anything unusual down here, that it might pay us to look up there.”

  He got briskly off the table on which he was sitting (for the only chair was allotted to Sir Walter) and ran rapidly up the ladder to the platform above. He was soon followed by the others, Mr. Fisher going last, however, with an appearance of considerable nonchalance.

  At this stage, however, they were destined to disappointment; Wilson nosed in every corner like a terrier and examined the roof almost in the posture of a fly, but half an hour afterward they had to confess that they were still without a clew. Sir Walter’s private secretary seemed more and more threatened with inappropriate slumber, and, having been the last to climb up the ladder, seemed now to lack the energy even to climb down again.

  “Come along, Fisher,” called out Sir Walter from below, when the others had regained the floor. “We must consider whether we’ll pull the whole place to pieces to see what it’s made of.”

  “I’m coming in a minute,” said the voice from the ledge above their heads, a voice somewhat suggestive of an articulate yawn.

  “What are you waiting for?” asked Sir Walter, impatiently. “Can you see anything there?”

  “Well, yes, in a way,” replied the voice, vaguely. “In fact, I see it quite plain now.”

  “What is it?” asked Wilson, sharply, from the table on which he sat kicking his heels restlessly.

  “Well, it’s a man,” said Horne Fisher.

  Wilson bounded off the table as if he had been kicked off it. “What do you mean?” he cried. “How can you possibly see a man?”

  “I can see him through the window,” replied the secretary, mildly. “I see him coming across the moor. He’s making a bee line across the open country toward this tower. He evidently means to pay us a visit. And, considering who it seems to be, perhaps it would be more polite if we were all at the door to receive him.” And in a leisurely manner the secretary came down the ladder.

  “Who it seems to be!” repeated Sir Walter in astonishment.

  “Well, I think it’s the man you call Prince Michael,” observed Mr. Fisher, airily. “In fact, I’m sure it is. I’ve seen the police portraits of him.”

  There was a dead silence, and Sir Walter’s usually steady brain seemed to go round like a windmill.

  “But, hang it all!” he said at last, “even supposing his own explosion could have thrown him half a mile away, without passing through any of the windows, and left him alive enough for a country walk — even then, why the devil should he walk in this direction? The murderer does not generally revisit the scene of his crime so rapidly as all that.”

  “He doesn’t know yet that it is the scene of his crime,” answered Horne Fisher.

  “What on earth do you mean? You credit him with rather singular absence of mind.”

  “Well, the truth is, it isn’t the scene of his crime,” said Fisher, and went and looked out of the window.

  There was another silence, and then Sir Walter said, quietly: “What sort of notion have you really got in your head, Fisher? Have you developed a new theory about how this fellow escaped out of the ring round him?”

  “He never escaped at all,” answered the man at the window, without turning round. “He never escaped out of the ring because he was never inside the ring. He was not in this tower at all, at least not when we were surrounding it.”

  He turned and leaned back against the window, but, in spite of his usual listless manner, they almost fancied that the face in shadow was a little pale.

  “I began to guess something of the sort when we were some way from the tower,” he said. “Did you notice that sort of flash or flicker the candle gave before it was extinguished? I was almost certain it was only the last leap the flame gives when a candle burns itself out. And then I came into this room and I saw that.”

  He pointed at the table and Sir Walter caught his breath with a sort of curse at his own blindness. For the candle in the candlestick had obviously burned itself away to nothing and left him, mentally, at least, very completely in the dark.

  “Then there is a sort of mathematical question,” went on Fisher, leaning back in his limp way and looking up at the bare walls, as if tracing imaginary diagrams there. “It’s not so easy for a man in the third angle to face the other two at the same moment, especially if they are at the base of an isosceles. I am sorry if it sounds like a lecture on geometry, but—”

  “I’m afraid we have no time for it,” said Wilson, coldly. “If this man is really coming back, I must give my orders at once.”

  “I think I’ll go on with it, though,” observed Fisher, staring at the roof with insolent serenity.

  “I must ask you, Mr. Fisher, to let me conduct my inquiry on my own lines,” said Wilson, firmly. “I am the officer in charge now.”

  “Yes,” remarked Horne Fisher, softly, but with an accent that somehow chilled the hearer. “Yes. But why?”

  Sir Walter was staring, for he had never seen his rather lackadaisical young friend look like that before. Fisher was looking at Wilson with lifted lids, and the eyes under them seemed to have shed or shifted a film, as do the eyes of an eagle.

  “Why are you the officer in charge now?” he asked. “Why can you conduct the inquiry on your own lines now? How did it come about, I wonder, that the elder officers are not here to interfere with anything you do?”

  Nobody spoke, and nobody can say how soon anyone would have collected his wits to speak when a noise came from without. It was the heavy and hollow sound of a blow upon the door of the tower, and to their shaken spirits it sounded strangely like the hammer of doom.

  The wooden door of the tower moved on its rusty hinges under the hand that struck it and Prince Michael came into the room. Nobody had the smallest doubt about his identity. His light clothes, though frayed with his adventures, were of fine and almost foppish cut, and he wore a pointed beard, or imperial, perhaps as a further reminiscence of Louis Napoleon; but he was a much taller and more graceful man that his prototype. Before anyone could speak he had silenced everyone for an instant with a slight but splendid gesture of hospitality.

  “Gentlemen,” he said, “this is a poor place now, but you are heartily welcome.”

  Wilson was the first to recover, and he took a stride toward the newcomer.

  “Michael O’Neill, I arrest you in the king’s name for the murder of Francis Morton and James Nolan. It is my duty to warn you—”

  “No, no, Mr. Wilson,” cried Fisher, suddenly. “You shall not commit a third murder.”

  Sir Walter Carey rose from his chair, which fell over with a crash behind him. “What does all this mean?” he called out in an authoritative manner.

  “It means,” said Fisher, “that this man, Hooker Wilson, as soon as he had put his head in at that window, killed his two comrades who had put their heads in at the other windows, by firing across the empty room. That is what it means. And if you want to know, count how many times he is supposed to have fired and then count the charges left in his revolver.”

  Wilson, who was still sitting on the table, abruptly put a hand out for the weapon that lay beside him. But the next movement was the most unexpected of all, for the prince standing in the doorway passed suddenly from the dignity of a statue to the swiftness of an acrobat and rent the revolver out of the detective’s hand.

  “You dog!” he cried. “So you are the type of English truth, as I am of Irish tragedy — you who come to kill me, wading through the blood of your brethren. If they had fallen in a feud on the hillside, it would be called murder, and yet your sin might be forgiven you. But I, who am innocent, I was to be slain with ceremony. There would be long speeches and patient judges listening to my vain plea of innocence, noting down my despair and disregarding it. Yes, that is what I call assassination. But killing may be no murder; there is one shot left in this little gun, and I know where it should go.”