Galloway was crying: "A corpse in the grass—a blood-stained corpse." O'Brien at last had gone utterly out of his mind.
"We must tell Valentin at once," said the doctor, when the other had brokenly described all that he had dared to examine. "It is fortunate that he is here"; and even as he spoke the great detective entered the study, attracted by the cry. It was almost amusing to note his typical transformation; he had come with the common concern of a host and a gentleman, fearing that some guest or servant was ill. When he was told the gory fact, he turned with all his gravity instantly bright and businesslike; for this, however abrupt and awful, was his business.
"Strange, gentlemen," he said as they hurried out into the garden, "that I should have hunted mysteries all over the earth, and now one comes and settles in my own back-yard. But where is the place?" They crossed the lawn less easily, as a slight mist had begun to rise from the river; but under the guidance of the shaken Galloway they found the body sunken in deep grass—the body of a very tall and broad-shouldered man. He lay face downwards, so they could only see that his big shoulders were clad in black cloth, and that his big head was bald, except for a wisp or two of brown hair that clung to his skull like wet seaweed. A scarlet serpent of blood crawled from under his fallen face.
"At least," said Simon, with a deep and singular intonation, "he is none of our party."
"Examine him, doctor," cried Valentin rather sharply. "He may not be dead."
The doctor bent down. "He is not quite cold, but I am afraid he is dead enough," he answered. "Just help me to lift him up."
They lifted him carefully an inch from the ground, and all doubts as to his being really dead were settled at once and frightfully. The head fell away. It had been entirely sundered from the body; whoever had cut his throat had managed to sever the neck as well. Even Valentin was slightly shocked. "He must have been as strong as a gorilla," he muttered.
Not without a shiver, though he was used to anatomical abortions, Dr. Simon lifted the head. It was slightly slashed about the neck and jaw, but the face was substantially unhurt. It was a ponderous, yellow face, at once sunken and swollen, with a hawk-like nose and heavy lids—a face of a wicked Roman emperor, with, perhaps, a distant touch of a Chinese emperor. All present seemed to look at it with the coldest eye of ignorance. Nothing else could be noted about the man except that, as they had lifted his body, they had seen underneath it the white gleam of a shirt-front defaced with a red gleam of blood. As Dr. Simon said, the man had never been of their party. But he might very well have been trying to join it, for he had come dressed for such an occasion.
Valentin went down on his hands and knees and examined with his closest professional attention the grass and ground for some twenty yards round the body, in which he was assisted less skillfully by the doctor, and quite vaguely by the English lord. Nothing rewarded their grovellings except a few twigs, snapped or chopped into very small lengths, which Valentin lifted for an instant's examination and then tossed away.
"Twigs," he said gravely; "twigs, and a total stranger with his head cut off; that is all there is on this lawn."
There was an almost creepy stillness, and then the unnerved Galloway called out sharply:
"Who's that! Who's that over there by the garden wall!"
A small figure with a foolishly large head drew waveringly near them in the moonlit haze; looked for an instant like a goblin, but turned out to be the harmless little priest whom they had left in the drawing-room.
"I say," he said meekly, "there are no gates to this garden, do you know."
Valentin's black brows had come together somewhat crossly, as they did on principle at the sight of the cassock. But he was far too just a man to deny the relevance of the remark. "You are right," he said. "Before we find out how he came to be killed, we may have to find out how he came to be here. Now listen to me, gentlemen. If it can be done without prejudice to my position and duty, we shall all agree that certain distinguished names might well be kept out of this. There are ladies, gentlemen, and there is a foreign ambassador. If we must mark it down as a crime, then it must be followed up as a crime. But till then I can use my own discretion. I am the head of the police; I am so public that I can afford to be private. Please Heaven, I will clear everyone of my own guests before I call in my men to look for anybody else. Gentlemen, upon your honour, you will none of you leave the house till to-morrow at noon; there are bedrooms for all. Simon, I think you know where to find my man, Ivan, in the front hall; he is a confidential man. Tell him to leave another servant on guard and come to me at once. Lord Galloway, you are certainly the best person to tell the ladies what has happened, and prevent a panic. They also must stay. Father Brown and I will remain with the body."
When this spirit of the captain spoke in Valentin he was obeyed like a bugle. Dr. Simon went through to the armoury and routed out Ivan, the public detective's private detective. Galloway went to the drawing-room and told the terrible news tactfully enough, so that by the time the company assembled there the ladies were already startled and already soothed. Meanwhile the good priest and the good atheist stood at the head and foot of the dead man motionless in the moonlight, like symbolic statues of their two philosophies of death.
Ivan, the confidential man with the scar and the moustaches, came out of the house like a cannon ball, and came racing across the lawn to Valentin like a dog to his master. His livid face was quite lively with the glow of this domestic detective story, and it was with almost unpleasant eagerness that he asked his master's permission to examine the remains.
"Yes; look, if you like, Ivan," said Valentin, "but don't be long. We must go in and thrash this out in the house."
Ivan lifted the head, and then almost let it drop.
"Why," he gasped, "it's—no, it isn't; it can't be. Do you know this man, sir?"
"No," said Valentin indifferently; "we had better go inside."
Between them they carried the corpse to a sofa in the study, and then all made their way to the drawing-room.
The detective sat down at a desk quietly, and even without hesitation; but his eye was the iron eye of a judge at assize. He made a few rapid notes upon paper in front of him, and then said shortly: "Is everybody here?"
"Not Mr. Brayne," said the Duchess of Mont St. Michel, looking round.
"No," said Lord Galloway in a hoarse, harsh voice. "And not Mr. Neil O'Brien, I fancy. I saw that gentleman walking in the garden when the corpse was still warm."
"Ivan," said the detective, "go and fetch Commandant O'Brien and Mr. Brayne. Mr. Brayne, I know, is finishing a cigar in the dining-room; Commandant O'Brien, I think, is walking up and down the conservatory. I am not sure."
The faithful attendant flashed from the room, and before anyone could stir or speak Valentin went on with the same soldierly swiftness of exposition.
"Everyone here knows that a dead man has been found in the garden, his head cut clean from his body. Dr. Simon, you have examined it. Do you think that to cut a man's throat like that would need great force? Or, perhaps, only a very sharp knife?"
"I should say that it could not be done with a knife at all," said the pale doctor.
"Have you any thought," resumed Valentin, "of a tool with which it could be done?"
"Speaking within modern probabilities, I really haven't," said the doctor, arching his painful brows. "It's not easy to hack a neck through even clumsily, and this was a very clean cut. It could be done with a battle-axe or an old headsman's axe, or an old two-handed sword."
"But, good heavens!" cried the Duchess, almost in hysterics, "there aren't any two-handed swords and battle-axes round here."
Valentin was still busy with the paper in front of him. "Tell me," he said, still writing rapidly, "could it have been done with a long French cavalry sabre?"
A low knocking came at the door, which, for some unreasonable reason, curdled everyone's blood like the knocking in Macbeth. Amid that frozen silence Dr. Simon managed to say: "A sabre—yes, I suppose it could."
"Thank