sir arthur vaudrey, in his light-grey summer suit, and wearing on his grey head the white hat which he so boldly affected, went walking briskly up the road by the river from his own house to the little group of houses that were almost like outhouses to his own, entered that little hamlet, and then vanished completely as if he had been carried away by the fairies.

the disappearance seemed the more absolute and abrupt because of the familiarity of the scene and the extreme simplicity of the conditions of the problem. the hamlet could not be called a village; indeed, it was little more than a small and strangely-isolated street. it stood in the middle of wide and open fields and plains, a mere string of the four or five shops absolutely needed by the neighbours; that is, by a few farmers and the family at the great house. there was a butcher's at the corner, at which, it appeared, sir arthur had last been seen. he was seen by two young men staying at his house; evan smith, who was acting as his secretary, and john dalmon, who was generally supposed to be engaged to his ward. there was next to the butcher's a small shop combining a large number of functions, such as is found in villages, in which a little old woman sold sweets, walking-sticks, golf-balls, gum, balls of string and a very faded sort of stationery. beyond this was the tobacconist, to which the two young men were betaking themselves when they last caught a glimpse of their host standing in front of the butcher's shop; and beyond that was a dingy little dressmaker's, kept by two ladies. a pale and shiny shop, offering to the passer-by great goblets of very wan, green lemonade, completed the block of buildings; for the only real and christian inn in the neighbourhood stood by itself some way, down the main road. between the inn and the hamlet was a cross-roads, at which stood a policeman and a uniformed official of a motoring club; and both agreed that sir arthur had never passed that point on the road.

it had been at an early hour of a very brilliant summer day that the old gentleman had gone gaily striding up the road, swinging his walking-stick and flapping his yellow gloves. he was a good deal of a dandy, but one of a vigorous and virile sort, especially for his age. his bodily strength and activity were still very remarkable, and his curly hair might have been a yellow so pale as to look white instead of a white that was a faded yellow. his clean-shaven face was handsome, with a high-bridged nose like the duke of wellington's; but the most outstanding features were his eyes. they were not merely metaphorically outstanding; something prominent and almost bulging about them was perhaps the only disproportion in his features; but his lips were sensitive and set a little tightly, as if by an act of will. he was the squire of all that country and the owner of the little hamlet. in that sort of place everybody not only knows everybody else, but generally knows where anybody is at any given moment. the normal course would have been for sir arthur to walk to the village, to say whatever he wanted to say to the butcher or anybody else, and then walk back to his house again, all in the course of about half an hour: as the two young men did when they had bought their cigarettes. but they saw nobody on the road returning; indeed, there was nobody in sight except the one other guest at the house, a certain dr. abbott, who was sitting with his broad back to them on the river bank, very patiently fishing.

when all the three guests returned to breakfast, they seemed to think little or nothing of the continued absence of the squire; but when the day wore on and he missed one meal after another, they naturally began to be puzzled, and sybil rye, the lady of the household, began to be seriously alarmed. expeditions of discovery were dispatched to the village again and again without finding any trace; and eventually, when darkness fell, the house was full of a definite fear. sybil had sent for father brown, who was a friend of hers and had helped her out of a difficulty in the past; and under the pressure of the apparent peril he had consented to remain at the house and see it through.

thus it happened that when the new day's dawn broke without news, father brown was early afoot and on the look out for anything; his black, stumpy figure could be seen pacing the garden path where the garden was embanked along the river, as he scanned the landscape up and down with his short-sighted and rather misty gaze.

he realized that another figure was moving even more restlessly along the embankment, and saluted evan smith, the secretary, by name.

evan smith was a tall, fair-haired young man, looking rather harassed, as was perhaps natural in that hour of distraction. but something of the sort hung about him at all times. perhaps it was more marked because he had the sort of athletic reach and poise and the sort of leonine yellow hair and moustache which accompany (always in fiction and sometimes in fact) a frank and cheerful demeanour of "english youth." as in his case they accompanied deep and cavernous eyes and a rather haggard look, the contrast with the conventional tall figure and fair hair of romance may have had a touch of something sinister. but father brown smiled at him amiably enough and then said more seriously:

"this is a trying business."

"it's a very trying business for miss rye," answered the young man gloomily; "and i don't see why i should disguise what's the worst part of it for me, even if she is engaged to dalmon. shocked, i suppose?"

father brown did not look very much shocked, but his face was often rather expressionless; he merely said, mildly:

"naturally, we all sympathize with her anxiety. i suppose you haven't any news or views in the matter?"

"i haven't any news exactly." answered smith; "no news from outside at least. as for views...." and he relapsed into moody silence.

"i should be very glad to hear your views," said the little priest pleasantly. "i hope you don't mind my saying that you seem to have something on your mind."

the young man stirred rather than started and looked at the priest steadily, with a frown that threw his hollow eyes into dense shadow.

"well, you're right enough," he said at last. "i suppose i shall have to tell somebody. and you seem a safe sort of person to tell."

"do you know what has happened to sir arthur?" asked father brown calmly, as if it were the most casual matter in the world.

"yes," said the secretary harshly, "i think i know what has happened to sir arthur."

"a beautiful morning," said a bland voice in his ear; "a beautiful morning for a rather melancholy meeting."

this time the secretary jumped as if he had been shot, as the large shadow of dr. abbott fell across his path in the already strong sunshine. dr. abbott was still in his dressing-gown; a sumptuous oriental dressing-gown covered with coloured flowers and dragons, looking rather like one of the most brilliant flower beds that were growing under the glowing sun. he also wore large, flat slippers, which was doubtless why he had come so close to the others without being heard. he would normally have seemed the last person for such a light and airy approach, for he was a very big, broad and heavy man, with a powerful benevolent face very much sunburnt, in a frame of old-fashioned grey whiskers and chin beard, which hung about him luxuriantly, like the long, grey curls of his venerable head. his long slits of eyes were rather sleepy and, indeed, he was an elderly gentleman to be up so early; but he had a look at once robust and weather-beaten, as of an old farmer or sea captain who had once been out in all weathers. he was the only old comrade and contemporary of the squire in the company that met at the house.

"it seems truly extraordinary," he said, shaking his head. "those little houses are like dolls' houses, always open front and back, and there's hardly room to hide anybody, even if they wanted to hide him. and i'm sure they don't. dalmon and i cross-examined them all yesterday; they're mostly little old women that couldn't hurt a fly. the men are nearly all away harvesting, except the butcher; and arthur was seen coining out of the butcher's. and nothing could have happened along that stretch by the river, for i was fishing there all day."

then he looked at smith and the look in his long eyes seemed for the moment not only sleepy, but a little sly.

"i think you and dalmon can testify," he said, "that you saw me sitting there through your whole journey there and back."

"yes," said evan smith shortly, and seemed rather impatient at the long interruption.

"the only thing i can think of," went on dr. abbott slowly; and then the interruption was itself interrupted. a figure at once light and sturdy strode very rapidly across the green lawn between the gay flowerbeds, and john dalmon appeared among them, holding a paper in his hand. he was neatly dressed and rather swarthy, with a very fine square napoleonic face and very sad eyes; eyes so sad that they looked almost dead. he seemed to be still young, but his black hair had gone prematurely grey about the temples.

"i've just had this telegram from the police," he said "i wired to them last night and they say they're sending down a man at once. do you know, dr. abbott, of anybody else we ought to send for? relations, i mean, and that sort of thing."

"there is his nephew, vernon vaudrey, of course," said the old man. "if you will come with me, i think i can give you his address and—and tell you something rather special about him."

dr. abbott and dalmon moved away in the direction of the house and, when they had gone a certain distance, father brown said simply, as if there had been no interruption:

"you were saying?"

"you're a cool hand," said the secretary. "i suppose it comes of hearing confessions. i feel rather as if i were going to make a confession. some people would feel a bit jolted out of the mood of confidence by that queer old elephant creeping up like a snake. but i suppose i'd better stick to it, though it really isn't my confession, but somebody else's." he stopped a moment, frowning and pulling his moustache; then he said, abruptly:

"i believe sir arthur has bolted, and i believe i know why."

there was a silence and then he exploded again.

"i'm in a damnable position, and most people would say i was doing a damnable thing. i am now going to appear in the character of a sneak and a skunk and i believe i am doing my duty."

"you must be the judge," said father brown gravely. "what is the matter with your duty?"

"i'm in the perfectly foul position of telling tales against a rival, and a successful rival, too," said the young man bitterly; "and i don't know what else in the world i can do. you were asking what was the explanation of vaudrey's disappearance. i am absolutely convinced that dalmon is the explanation."

"you mean," said the priest, with composure, "that dalmon has killed sir arthur?"

"no!" exploded smith, with startling violence. "no, a hundred times! he hasn't done that, whatever else he's done. he isn't a murderer, whatever else he is. he has the best of all alibis; the evidence of a man who hates him. i'm not likely to perjure myself for love of dalmon; and i could swear in any court he did nothing to the old man yesterday. dalmon and i were together all day, or all that part of the day, and he did nothing in the village except buy cigarettes, and nothing here except smoke them and read in the library. no; i believe he is a criminal, but he did not kill vaudrey. i might even say more; because he is a criminal he did not kill vaudrey."

"yes," said the other patiently, "and what does that mean?"

"it means," replied the secretary, "that he is a criminal committing another crime: and his crime depends on keeping vaudrey alive."

"oh, i see," said father brown.

"i know sybil rye pretty well, and her character is a great part of this story. it is a very fine character in both senses: that is, it is of a noble quality and only too delicate a texture. she is one of those people who are terribly conscientious, without any of that armour of habit and hard common sense that many conscientious people get. she is almost insanely sensitive and at the same time quite unselfish. her history is curious: she was left literally penniless like a foundling and sir arthur took her into his house and treated her with consideration, which puzzled many; for, without being hard on the old man, it was not much in his line. but, when she was about seventeen, the explanation came to her with a shock; for her guardian asked her to marry him. now i come to the curious part of the story. somehow or other, sybil had heard from somebody (i rather suspect from old abbott) that sir arthur vaudrey, in his wilder youth, had committed some crime or, at least, done some great wrong to somebody, which had got him into serious trouble. i don't know what it was. but it was a sort of nightmare to the girl at her crude sentimental age, and made him seem like a monster, at least too much so for the close relation of marriage. what she did was incredibly typical of her. with helpless terror and with heroic courage she told him the truth with her own trembling lips. she admitted that her repulsion might be morbid; she confessed it like a secret madness. to her relief and surprise he took it quietly and courteously, and apparently said no more on the subject; and her sense of his generosity was greatly increased by the next stage of the story. there came into her lonely life the influence of an equally lonely man. he was camping-out like a sort of hermit on one of the islands in the river; and i suppose the mystery made him attractive, though i admit he is attractive enough; a gentleman, and quite witty, though very melancholy—which, i suppose, increased the romance. it was this man, dalmon, of course; and to this day i'm not sure how far she really accepted him; but it got as far as his getting permission to see her guardian. i can fancy her awaiting that interview in an agony of terror and wondering how the old beau would take the appearance of a rival. but here, again, she found she had apparently done him an injustice. he received the younger man with hearty hospitality and seemed to be delighted with the prospects of the young couple. he and dalmon went shooting and fishing together and were the best of friends, when one day she had another shock. dalmon let slip in conversation some chance phrase that the old man 'had not changed much in thirty years,' and the truth about the odd intimacy burst upon her. all that introduction and hospitality had been a masquerade; the men had obviously known each other before. that was why the younger man had come down rather covertly to that district. that was why the elder man was lending himself so readily to promote the match. i wonder what you are thinking?"

"i know what you are thinking," said father brown, with a smile, "and it seems entirely logical. here we have vaudrey, with some ugly story in his past; a mysterious stranger come to haunt him, and getting whatever he wants out of him. in plain words, you think dalmon is a blackmailer."

"i do," said the other; "and a rotten thing to think, too."

father brown reflected for a moment and then said: "i think i should like to go up to the house now and have a talk to dr. abbott."

when he came out of the house again an hour or two afterwards, he may have been talking to dr. abbott, but he emerged in company with sybil rye, a pale girl with reddish hair and a profile delicate and almost tremulous; at the sight other, one could instantly understand all the secretary's story of her shuddering candour. it recalled godiva and certain tales of virgin martyrs; only the shy can be so shameless for conscience's sake. smith came forward to meet them, and for a moment they stood talking on the lawn. the day which had been brilliant from daybreak was now glowing and even glaring; but father brown carried his black bundle of an umbrella as well as wearing his black umbrella of a hat; and seemed, in a general way, buttoned up to breast the storm. but perhaps it was only an unconscious effect of attitude; and perhaps the storm was not a material storm.

"what i hate about it all," sybil was saying in a low voice, "is the talk that's beginning already; suspicions against everybody. john and evan can answer for each other, i suppose; but dr. abbott has had an awful scene with the butcher, who thinks he is accused and is throwing accusations about in consequence."

evan smith looked very uncomfortable; then blurted out: "look here, sybil, i can't say much, but we don't believe there's any need for all that. it's all very beastly, but we don't think there's been—any violence."

"have you got a theory, then?" said the girl, looking instantly at the priest.

"i have heard a theory," he replied, "which seems to me very convincing."

he stood looking rather dreamily towards the river; and smith and sybil began to talk to each other swiftly, in lowered tones. the priest drifted along the river bank, ruminating, and plunged into a plantation of thin trees on an almost overhanging bank. the strong sun beat on the thin veil of little dancing leaves like small green flames, and all the birds were singing as if the tree had a hundred tongues. a minute or two later, evan smith heard his own name called cautiously and yet clearly from the green depths of the thicket. he stepped rapidly in that direction and met father brown returning. the priest said to him, in a very low voice:

"don't let the lady come down here. can't you get rid of her? ask her to telephone or something; and then come back here again."

evan smith turned with a rather desperate appearance of carelessness and approached the girl; but she was not the sort of person whom it is hard to make busy with small jobs for others. in a very short time she had vanished into the house and smith turned to find that father brown had once more vanished into the thicket. just beyond the clump of trees was a sort of small chasm where the turf had subsided to the level of the sand by the river. father brown was standing on the brink of this cleft, looking down; but, either by accident or design, he was holding his hat in his hand, in spite of the strong sun pouring on his head.

"you had better see this yourself," he said, heavily, "as a matter of evidence. but i warn you to be prepared."

"prepared for what?" asked the other.

"only for the most horrible thing i ever saw in my life," said father brown.

even smith stepped to the brink of the bank of turf and with difficulty repressed a cry rather like a scream.

sir arthur vaudrey was glaring and grinning up at him; the face was turned up so that he could have put his foot on it; the head was thrown back, with its wig of whitish yellow hair towards him, so that he saw the face upside down. this made it seem all the more like a part of a nightmare; as if a man were walking about with his head stuck on the wrong way. what was he doing? was it possible that vaudrey was really creeping about, hiding in the cracks of field and bank, and peering out at them in this unnatural posture? the rest of the figure seemed hunched and almost crooked, as if it had been crippled or deformed but on looking more closely, this seemed only the foreshortening of limbs fallen in a heap. was he mad? was he? the more smith looked at him the stiffer the posture seemed.

"you can't see it from here properly," said father brown, "but his throat is cut."

smith shuddered suddenly. "i can well believe it's the most horrible thing you've seen," he said. "i think it's seeing the face upside down. i've seen that face at breakfast, or dinner, every day for ten years; and it always looked quite pleasant and polite. you turn it upside down and it looks like the face of a fiend."

"the face really is smiling," said father brown, soberly; "which is perhaps not the least part of the riddle. not many men smile while their throats are being cut, even if they do it themselves. that smile, combined with those gooseberry eyes of his that always seemed standing out of his head, is enough, no doubt, to explain the expression. but it's true, things look different upside down. artists often turn their drawings upside down to test their correctness. sometimes, when it's difficult to turn the object itself upside down (as in the case of the matterhorn, let us say), they have been known to stand on their heads, or at least look between their legs."

the priest, who was talking thus flippantly to steady the other man's nerves, concluded by saying, in a more serious tone: "i quite understand how it must have upset you. unfortunately, it also upset something else."

"what do you mean?"

"it has upset the whole of our very complete theory," replied the other; and he began clambering down the bank on to the little strip of sand by the river.

"perhaps he did it himself," said smith abruptly. "after all, that's the most obvious sort of escape, and fits in with our theory very well. he wanted a quiet place and he came here and cut his throat."

"he didn't come here at all," said father brown. "at least, not alive, and not by land. he wasn't killed here; there's not enough blood. this sun has dried his hair and clothes pretty well by now; but there are the traces of two trickles of water in the sand. just about here the tide comes up from the sea and makes an eddy that washed the body into the creek and left it when the tide retired. but the body must first have been washed down the river, presumably from the village, for the river runs just behind the row of little houses and shops. poor vaudrey died up in the hamlet, somehow; after all, i don't think he committed suicide; but the trouble is who would, or could, have killed him up in that potty little place?"

he began to draw rough designs with the point of his stumpy umbrella on the strip of sand.

"let's see; how does the row of shops run? first, the butcher's; well, of course, a butcher would be an ideal performer with a large carving knife. but you saw vaudrey come out, and it isn't very probable that he stood in the outer shop while the butcher said: 'good morning. allow me to cut your throat! thank you. and the next article, please?' sir arthur doesn't strike me as the sort of man who'd have stood there with a pleasant smile while this happened. he was a very strong and vigorous man, with rather a violent temper. and who else, except the butcher, could have stood up to him? the next shop is kept by an old woman. then comes the tobacconist, who is certainly a man, but i am told quite a small and timid one. then there is the dressmaker's, run by two maiden ladies, and then a refreshment shop run by a man who happens to be in hospital and who has left his wife in charge. there are two or three village lads, assistants and errand boys, but they were away on a special job. the refreshment shop ends the street; there is nothing beyond that but the inn, with the policeman between."

he made a punch with the ferrule of his umbrella to represent the policeman, and remained moodily staring up the river. then he made a slight movement with his hand and, stepping quickly across, stooped over the corpse.

"ah," he said, straightening himself and letting out a great breath. "the tobacconist! why in the world didn't i remember that about the tobacconist?"

"what is the matter with you?" demanded smith in some exasperation; for father brown was rolling his eyes and muttering, and he had uttered the word "tobacconist" as if it were a terrible word of doom.

"did you notice," said the priest, after a pause, "something rather curious about his face?"

"curious, my god!" said evan, with a retrospective shudder. "anyhow, his throat was cut...."

"i said his face," said the cleric quietly. "besides, don't you notice he has hurt his hand and there's a small bandage round it?"

"oh, that has nothing to do with it," said evan hastily. "that happened before and was quite an accident. he cut his hand with a broken ink-bottle while we were working together."

"it has something to do with it, for all that," replied father brown.

there was a long silence, and the priest walked moodily along the sand, trailing his umbrella and sometimes muttering the word "tobacconist," till the very word chilled his friend with fear. then he suddenly lifted the umbrella and pointed to a boathouse among the rushes.

"is that the family boat?" he asked. "i wish you'd just scull me up the river; i want to look at those houses from the back. there's no time to lose. they may find the body; but we must risk that."

smith was already pulling the little boat upstream towards the hamlet before father brown spoke again. then he said:

"by the way, i found out from old abbott what was the real story about poor vaudrey's misdemeanour. it was a rather curious story about an egyptian official who had insulted him by saying that a good moslem would avoid swine and englishmen, but preferred swine; or some such tactful remark. whatever happened at the time, the quarrel was apparently renewed some years after, when the official visited england; and vaudrey, in his violent passion, dragged the man to a pig-sty on the farm attached to the country house and threw him in, breaking his arm and leg and leaving him there till next morning. there was rather a row about it, of course, but many people thought vaudrey had acted in a pardonable passion of patriotism. anyhow, it seems not quite the thing that would have kept a man silent under deadly blackmail for decades."

"then you don't think it had anything to do with the story we are considering?" asked the secretary, thoughtfully.

"i think it had a thundering lot to do with the story i am considering now," said father brown.

they were now floating past the low wall and the steep strips of back garden running down from the back doors to the river. father brown counted them carefully, pointing with his umbrella, and when he came to the third he said again:

"tobacconist! is the tobacconist by any chance.... but i think i'll act on my guess till i know. only, i'll tell you what it was i thought odd about sir arthur's face."

"and what was that?" asked his companion, pausing and resting on his oars for an instant.

"he was a great dandy," said father brown, "and the face was only half-shaved.... could you stop here a moment? we could tie up the boat to that post."

a minute or two afterwards they had clambered over the little wall and were mounting the steep cobbled paths of the little garden, with its rectangular beds of vegetables and flowers.

"you see, the tobacconist does grow potatoes," said father brown. "associations with sir walter raleigh, no doubt. plenty of potatoes and plenty of potato sacks. these little country people have not lost all the habits of peasants; they still run two or three jobs at once. but country tobacconists very often do one odd job extra, that i never thought of till i saw vaudrey's chin. nine times out of ten you call the shop the tobacconist's, but it is also the barber's. he'd cut his hand and couldn't shave himself; so he came up here. does that suggest anything else to you?"

"it suggests a good deal," replied smith; "but i expect it will suggest a good deal more to you."

"does it suggest, for instance," observed father brown, "the only conditions in which a vigorous and rather violent gentleman might be smiling pleasantly when his throat was cut?"

the next moment they had passed through a dark passage or two at the back of the house, and came into the back room of the shop, dimly lit by filtered light from beyond and a dingy and cracked looking-glass. it seemed, somehow, like the green twilight of a tank; but there was light enough to see the rough apparatus of a barber's shop and the pale and even panic-sticken face of a barber.

father brown's eye roamed round the room, which seemed to have been just recently cleaned and tidied, till his gaze found something in a dusty corner just behind the door. it was a hat hanging on a hat-peg. it was a white hat, and one very well known to all that village. and yet, conspicuous as it had always seemed in the street, it seemed only an example of the sort of little thing a certain sort of man often entirely forgets, when he has most carefully washed floors or destroyed stained rags.

"sir arthur vaudrey was shaved here yesterday morning, i think," said father brown in a level voice.

to the barber, a small, bald-headed, spectacled man whose name was wicks, the sudden appearance of these two figures out of his own back premises was like the appearance of two ghosts risen out of a grave under the floor. but it was at once apparent that he had more to frighten him than any fancy of superstition. he shrank, we might almost say that he shrivelled, into a corner of the dark room; and everything about him seemed to dwindle, except his great goblin spectacles.

"tell me one thing," continued the priest, quietly. "you had a reason for hating the squire?"

the man in the corner babbled something that smith could not hear; but the priest nodded.

"i know you had," he said. "you hated him; and that's how i know you didn't kill him. will you tell us what happened, or shall i?"

there was a silence filled with the faint ticking of a clock in the back kitchen; and then father brown went on.

"what happened was this. when mr. dalmon stepped inside your outer shop, he asked for some cigarettes that were in the window. you stepped outside for a moment, as shopmen often do, to make sure of what he meant; and in that moment of time he perceived in the inner room the razor you had just laid down, and the yellow-white head of sir arthur in the barber's chair; probably both glimmering in the light of that little window beyond. it took but an instant for him to pick up the razor and cut the throat and come back to the counter. the victim would not even be alarmed at the razor and the hand. he died smiling at his own thoughts. and what thoughts! nor, i think, was dalmon alarmed. he had done it so quickly and quietly that mr. smith here could have sworn in court that the two were together all the time. but there was somebody who was alarmed, very legitimately, and that was you. you had quarrelled with your landlord about arrears of rent and so on; you came back into your own shop and found your enemy murdered in your own chair, with your own razor. it was not altogether unnatural that you despaired of clearing yourself, and preferred to clear up the mess; to clean the floor and throw the corpse into the river at night, in a potato sack rather loosely tied. it was rather lucky that there were fixed hours after which your barber's shop was shut; so you had plenty of time. you seem to have remembered everything but the hat.... oh, don't be frightened; i shall forget everything, including the hat."

and he passed placidly through the outer shop into the street beyond, followed by the wondering smith, and leaving behind the barber stunned and staring.

"you see," said father brown to his companion, "it was one of those cases where a motive really is too weak to convict a man and yet strong enough to acquit him. a little nervous fellow like that would be the last man really to kill a big strong man for a tiff about money. but he would be the first man to fear that he would be accused of having done it.... ah, there was a thundering difference in the motive of the man who did do it." and he relapsed into reflection, staring and almost glaring at vacancy.

"it is simply awful," groaned evan smith. "i was abusing dalmon as a blackmailer and a blackguard an hour or two ago, and yet it breaks me all up to hear he really did this, after all."

the priest still seemed to be in a sort of trance, like a man staring down into an abyss. at last his lips moved and he murmured, more as if it were a prayer than an oath: "merciful god, what a horrible revenge!"

his friend questioned him, but he continued as if talking to himself.

"what a horrible tale of hatred! what a vengeance for one mortal worm to take on another! shall we ever get to the bottom of this bottomless human heart, where such abominable imaginations can abide? god save us all from pride; but i cannot yet make any picture in my mind of hate and vengeance like that."

"yes," said smith; "and i can't quite picture why he should kill vaudrey at all. if dalmon was a blackmailer, it would seem more natural for vaudrey to kill him. as you say, the throat-cutting was a horrid business, but——"

father brown started, and blinked like a man awakened from sleep.

"oh, that!" he corrected hastily. "i wasn't thinking about that. i didn't mean the murder in the barber's shop, when—when i said a horrible tale of vengeance. i was thinking of a much more horrible tale than that; though, of course, that was horrible enough, in its way. but that was much more comprehensible; almost anybody might have done it. in fact, it was very nearly an act of self-defence."

"what?" exclaimed the secretary incredulously. "a man creeps up behind another man and cuts his throat, while he is smiling pleasantly at the ceiling in a barber's chair, and you say it was self-defence!"

"i do not say it was justifiable self-defence," replied the other. "i only say that many a man would have been driven to it, to defend himself against an appalling calamity—which was also an appalling crime. it was that other crime that i was thinking about. to begin with, about that question you asked just now; why should the blackmailer be the murderer? well, there are a good many conventional confusions and errors on a point like that." he paused, as if collecting his thoughts after his recent trance of horror, and went on in ordinary tones.

"you observe that two men, an older and a younger, go about together and agree on a matrimonial project; but the origin of their intimacy is old and concealed. one is rich and the other poor; and you guess at blackmail. you are quite right, at least to that extent. where you are quite wrong is in guessing which is which. you assume that the poor man was blackmailing the rich man. as a matter offset, the rich man was blackmailing the poor man."

"but that seems nonsense," objected the secretary.

"it is much worse than nonsense; but it is not at all uncommon," replied the other. "half modern politics consists of rich men blackmailing people. your notion that it's nonsense rests on two illusions which are both nonsensical. one is, that rich men never want to be richer; the other is, that a man can only be blackmailed for money. it's the last that is in question here. sir arthur vaudrey was acting not for avarice, but for vengeance. and he planned the most hideous vengeance i ever heard of."

"but why should he plan vengeance on john dalmon?" inquired smith.

"it wasn't on john dalmon that he planned vengeance," replied the priest, gravely.

there was a silence; and he resumed, almost as if changing the subject. "when we found the body, you remember, we saw the face upside down; and you said it looked like the face of a fiend. has it occurred to you that the murderer also saw the face upside down, coming behind the barber's chair?"

"but that's all morbid extravagance," remonstrated his companion. "i was quite used to the face when it was the right way up."

"perhaps you have never seen it the right way up," said father brown. "i told you that artists turn a picture the wrong way up when they want to see it the right way up. perhaps, over all those breakfasts and tea-tables, you had got used to the face of a fiend."

"what on earth are you driving at?" demanded smith, impatiently.

"i speak in parables," replied the other in a rather sombre tone "of course. sir arthur was not actually a fiend; he was a man with a character which he had made out of a temperament that might also have been turned to good. but those goggling, suspicious eyes; that tight, yet quivering mouth, might have told you something if you had not been so used to them. you know, there are physical bodies on which a wound will not heal. sir arthur had a mind of that sort. it was as if it lacked a skin; he had a feverish vigilance of vanity; those strained eyes were open with an insomnia of egoism. sensibility need not be selfishness. sybil rye, for instance, has the same thin skin and manages to be a sort of saint. but vaudrey had turned it all to poisonous pride; a pride that was not even secure and self-satisfied. every scratch on the surface of his soul festered. and that is the meaning of that old story about throwing the man into the pig-sty. if he'd thrown him then and there, after being called a pig, it might have been a pardonable burst of passion. but there was no pig-sty; and that is just the point. vaudrey remembered the silly insult for years and years, till he could get the oriental into the improbable neighbourhood of a pig-sty; and then he took, what he considered the only appropriate and artistic revenge.... oh, my god! he liked his revenges to be appropriate and artistic."

smith looked at him curiously. "you are not thinking of the pig-sty story," he said.

"no," said father brown; "of the other story." he controlled the shudder in his voice, and went on.

"remembering that story of a fantastic and yet patient plot to make the vengeance fit the crime, consider the other story before us. had anybody else, to your knowledge, ever insulted vaudrey, or offered him what he thought a mortal insult? yes; a woman insulted him."

a sort of vague horror began to dawn in evan's eyes; he was listening intently.

"a girl, little more than a child, refused to marry him, because he had once been a sort of criminal; had, indeed, been in prison for a short time for the outrage on the egyptian. and that madman said, in the hell of his heart: 'she shall marry a murderer.'"

they took the road towards the great house and went along by the river for some time in silence, before he resumed: "vaudrey was in a position to blackmail dalmon, who had committed a murder long ago; probably he knew of several crimes among the wild comrades of his youth. probably it was a wild crime with some redeeming features; for the wildest murders are never the worst. and dalmon looks to me like a man who knows remorse, even for killing vaudrey. but he was in vaudrey's power and, between them, they entrapped the girl very cleverly into an engagement; letting the lover try his luck first, for instance, and the other only encouraging magnificently. but dalmon himself did not know, nobody but the devil himself did know, what was really in that old man's mind.

"then, a few days ago, dalmon made a dreadful discovery. he had obeyed, not altogether unwillingly; he had been a tool; and he suddenly found how the tool was to be broken and thrown away. he came upon certain notes of vaudrey's in the library which, disguised as they were, told of preparations for giving information to the police. he understood the whole plot and stood stunned as i did when i first understood it. the moment the bride and bridegroom were married, the bridegroom would be arrested and hanged. the fastidious lady, who objected to a husband who had been in prison, should have no husband except a husband on the gallows. that is what sir arthur vaudrey considered an artistic rounding off of the story."

evan smith, deadly pale, was silent; and, far away, down the perspective of the road, they saw the large figure and wide hat of dr. abbott advancing towards them; even in the outline there was a certain agitation. but they were still shaken with their own private apocalypse.

"as you say, hate is a hateful thing," said evan at last; "and, do you know, one thing gives me a sort of relief. all my hatred of poor dalmon is gone out of me—now i know how he was twice a murderer."

it was in silence that they covered the rest of the distance and met the big doctor coming towards them, with his large gloved hands thrown out in a sort of despairing gesture and his grey beard tossing in the wind.

"there is dreadful news," he said. "arthur's body has been found. he seems to have died in his garden."

"dear me," said father brown, rather mechanically. "how dreadful!"

"and there is more," cried the doctor breathlessly. "john dalmon went off to see vernon vaudrey, the nephew; but vernon vaudrey hasn't heard of him and dalmon seems to have disappeared entirely."

"dear me," said father brown. "how strange!"