A quarter of an hour later the detective was being ushered into a large, homely kitchen, and the expoliceman was putting a cold leg of pork upon the table.

“We’ve got the whole place to ourselves today,” he explained, “for the children are at school and the missis is out gadding about. I let her out of the cells for the day, and she’s in Downham Market buying things we don’t need and don’t want. Bless her heart! She’s like all women — directly she’s got a few bob in her pocket she must let them go. Beer? Ah! that’s right. I thought you might be one of those tea-drinking fiends.” He went on. “I remember there was a doctor once on my beat, a very clever chap, but always on the booze, and many a time I’ve popped him into his own doorway, instead of running him into the station as I ought to have done. Well, he told me once that the early morning cup of tea some people take was more responsible for indigestion than anything else. He was a fine fellow and married a barmaid afterwards, and then she wouldn’t let him touch a drop of drink. Cut it right out and made a splendid chap of him. When I left the Force he had got four kiddies and was a bit of a nob on Harley street. Consulting physician and becoming a big bug on nerves.”

They proceeded to do justice to the meal, and then suddenly, looking out of the window, Hart remarked, “My days! but your luck’s in, Mr. Larose. There’s a fog coming up from over the Fens and I’m thinking that’s the only hope in the world of you getting near Fensum’s place without being seen.”

“Oh!” exclaimed Larose, “do you get bad fogs here?”

Hart laughed. “Bad!” he exclaimed, “why, good old London’s nothing to them! Mind you, they’re not black or yellow, but just a thick, heavy white. They come up all at once, and they may last a fortnight, and when they’re really bad you can’t see your own feet. Then it’s almost like having a blanket over your head.” He nodded. “I’ll lend you my little compass, and you can send it back any time. I shan’t be here tomorrow, though, for the missis is giving me a holiday, and I’m going to London for the day.”

“Well, about this man Fensum,” asked Larose, “what is the name of his place?”

“Black Gallows,” replied Hart, with a grin, “and it seems like proving a darned appropriate name.” He looked intently at the detective. “But the more I think about it, sir, the more I’m inclined to believe that if there’s anything in the nature of a gang up there, as seems to be your idea — then you’re taking a great risk, going alone.”

“But I’m not going to make any arrests today,” replied Larose, “I only just want to get a peep at all the men who are living there. I’ve some good glasses with me and if I get within half a mile of them, it will do.”

“And that’s about as near as you will get,” nodded the expoliceman, “for it’s all level ground at once when you get on Fensum’s lands. He’s got about 1,600 acres of it and every yard was swamp and quagmire once.” He looked very serious. “It’s a regular trap for anyone, directly they get on it, who doesn’t know the place, for it’s cut off from everywhere by great wide drains, deep dykes, and the dangerous little River Wissey. Apart from that, it’s criss-crossed in lots of places with dykes that, although they are certainly not so wide, you would never get over.”

“Why not?” asked Larose. “I could swim at a pinch.”

“Swim!” ejaculated Hart scornfully. “Yes, you could swim if there was any depth of water in them, but you couldn’t swim in the Fen mud. There’s nothing like it anywhere else. It’s ten and twelve feet deep in parts, as thick almost, as tar, and as heavy as lead when it clings to you.” His eyes dilated. “Why, I saw a bullock once disappear in less than three minutes after it had slipped down into the Big Cut Drain that borders upon one side of Fensum’s property.” He shook his head. “No, Mr. Larose, as well face a bullet at point-blank range as try to cross over those drains.”

“Well, tell me how I’ll get there,” said Larose, in no way dismayed, “and I’ll take a chance. It’s like this, Mr. Hart,” he added, “I may be entirely at fault in my suspicions and this Fensum may be a perfectly innocent man, and there may be no one upon his premises who has done anything wrong. So, I don’t want to come down with a search warrant and a large party of officers, and besides making a fool of myself, rouse all the countryside, and give the real culprit a chance of breaking away when they learn I’m after them. I want to be sure, first. I want to catch sight of either one of two men, and then I shall be certain once and for all how I stand.”

“You’ve no certain knowledge then,” asked Hart, “that any of the men who are wanted are there?”

“No,” replied Larose at once, “no certain knowledge at all, but”— he spoke very slowly —“I have come a long trail, and it leads most definitely to somewhere about here. To a man who has some reason for covering up all his tracks wherever he goes, who lives in the Fen country, who drives a Jehu car and uses false number-plates, and who, finally, has been in need of two valve-cap covers such as yours, within the past few days.” He broke off suddenly and asked, “Now, do you ever get any aeroplanes coming over here, on moonlight nights?”

Hart nodded. “Yes, we do, occasionally,” he replied. “Not very often, but when we do get one, we always get two”— he frowned —“or, now that you are making me suspicious about everything, we hear the same one going and returning.”

“Exactly!” commented Larose, looking very pleased, “and it’s a dope gang I’m after. Someone drops the stuff, I’m thinking, from these aeroplanes you hear.” He smiled. “Another link in the chain, my friend.”

“All right,” said the expoliceman briskly, “and I’ll not try and dissuade you any more.” He fetched a piece of paper and a pencil. “I’ll draw you a map. Oh! that’s all right,” he went on as Larose took his ordinance map out of his pocket, “then I’ll only need to draw you one of Fensum’s place.”

They bent their heads over the map and he pointed out the way to the detective. “There’s Black Gallows, and it’s seven miles from here. Now, you’ll go along the Methwold Road until you see an inn on the left, just at the beginning of Methwold village.” He shook his head warningly. “But whatever you do, don’t go near that inn, for the proprietor, Jowles, is about the one pal Fensum has. He’s got a face like a ferret and if you ask anything about Black Gallows there it’s a hundred to one he’ll tell Fensum about it. So leave the main road about two hundred yards before you get to this inn and take the side road to the right. This road won’t look very inviting, because it’s always muddy. Then go straight along for about three miles until you come to a small plantation.” He paused for a moment and considered. “There, I think, you’d better leave the car, for beyond that it’d be a black spot on the landscape that could be picked up easily. Yes, run your car round the back of the plantation. There’s a dip in the ground there and it’ll be quite safe. Then about a quarter of a mile farther on you’ll come to a big, deep drain, about three times as wide as this room and you’ll see a gate, opening on to a black wooden bridge crossing the drain.”

“An iron gate?” asked Larose sharply, “that’s not been painted lately?”

“Yes,” nodded Hart looking very surprised, “how do you know that?”

“Only that the inside of the fingers and the palm of some motor gloves that belong to one of the men I’m looking for,” replied Larose, with difficulty suppressing the exultation that he felt, “smelt strongly of rust, when I was handling them the other day. Go on.”

“Open this gate — you’ll have to lift it up, for one of the posts has sunk — and cross over the bridge. It’s only made of planks and there are wide spaces between them.” He picked up his pencil and piece of paper. “Now comes the dangerous part of the journey, and I’ll draw you a map. Look, you’ll be now about two miles from Fensum’s houses. There are two of them. One is where they live, and the other is a long, two-storied building that is not occupied, and has long since fallen into ruins.”

“That’s interesting!” exclaimed Larose. “What was it built for?”

“It was the cracked idea of the man who had Black Gallows about thirty years ago,” replied Hart. “He was a Jew, called Bernstein, and he thought he would train horses upon Black Gallows and no one would be able to spy upon him, and learn how good his animals were. So he built a racing stable, with the ground floor all stalls and loose boxes for the horses, and the storey above them for his trainer and the stable hands. He spent a lot of money on it, and some of the rooms above were quite comfortably fitted up. But this Bernstein died, and, as I say, all the place has gone to ruin since.”

“What sort of a farmer is Fensum?” asked Larose.

Hart shook his head. “A poor one, and with plenty of good land, he makes little of it. He crops a few acres and he’s got a good few Romney Marsh sheep. But he never troubles much and folks often wonder how he makes it pay.” He looked down at the map he was drawing, and went on. “Well, now you’re inside Fensum’s property and your real difficulties begin. Don’t take the road leading up to the house, but hug the side of the big drain for about four hundred paces, then if there’s any fog, which it looks likely there will be, set your compass, turn off at right angles and, keeping straight north for two miles or just a little more, you will come bang up against these stables.”

The detective studied the map carefully. “It seems quite easy, Mr. Hart,” he said, “and I ought to have no difficulty.”

The expoliceman looked very serious. “But for the Lord’s sake,” he said warmly, “keep your eyes on this compass and go straight north the whole time, for if you don’t, you’ll get among a maze of dykes and you’ll never find your way back again, until the fog lifts.”

“And about those dogs,” said Larose thoughtfully, “do you know if they run loose after dark?”

“I should hardly think so,” replied Hart, “for no farmer leaves his dogs unchained at night. They don’t learn what discipline is if they’re not on the chain sometimes.” A thought came to him. “Now have you got a good knife on you, Mr. Larose!”

“A pocket one,” replied the detective, “but not a dagger.”

“Then I’ll lend you a bayonet,” replied Hart, “a good one that I took off a German on the glorious Vimy Ridge. Poor devil. I’d just given him the haymaker’s lift with mine.” He bent over towards Larose. “Now look here, sir, I’ll give you a good tip for dealing with a dog when it comes rushing at you. Meet it crouching down, or even, if you’ve got a good knife, some say, lying down. Then he loses all the benefit of his rush and the impetus of his big body doesn’t knock you over. I’ll give you a nice square of wire netting, too. That foggles them and you can strike through the meshes.” He shook his head. “I’m afraid for you if you meet with those Alsatians in the fog and don’t want to pistol them and let everyone know you are about the place. Generally, they don’t bark when they come to you. You only hear a blood-curdling snarl!”

The detective parted with much gratitude to the expoliceman for his kindness. “Really, my luck’s in,” he told himself, as he drove away, “and I couldn’t have met with a better man.”

Larose was rather disappointed when, for the first two miles or so, the weather appeared to be clearing, but when he judged he was halfway upon his journey, he ran all at once into a thick bank of fog and began to almost wish it had been so.

He could not see a dozen yards beyond the bonnet of his car, and he had to take out his ordnance map and with the help of an electric torch, tick off the turnings to the right and left as he went by.

He came at last to the turning on to the muddy road, and there was no doubt about the mud there, for his tyres squelched into it most unpleasantly and it was flung up in big spots all over the windscreen. In the fog he was desperately afraid of missing the plantation, but, taking Hart’s estimate of three miles as being quite accurate, he stopped when he had gone that distance and walked on on foot. But the estimate had been a very good one, and within a hundred yards he came upon the trees looming like ghosts out of the fog.

He parked the car where he had been advised and, greatly heartened that now he would find the going much easier, taking a few things from the tool-box, he set off blithely for Black Gallows.

He found the iron gate without much difficulty, and tip-toed up to it, with his heart beating strongly. “Yes, Gilbert, my boy,” he whispered, as he noted the rust upon his hands as he climbed over, “you’ve not lost quite all your punch yet, although you do make big bloomers every now and then.”

The fog was now lifting a little and he regarded with no pleasant feeling the deep, wide drain under the wooden bridge. It was evidently one of the main ones that had been dug to drain the Methwold Fens, and its waters, he judged, were at least fifteen feet below the top of the drain sides.

“A nice place to be thrown into,” he thought with something of a pang at the dangers that were now facing him, “but it would make funeral expenses very cheap.” He grinned. “What price, Gilbert, commencing your last long sleep down there, with the eels gnawing the ‘Dead March in Saul.’”

Still keeping most minutely to the directions of Dick Hart, be turned sharp to the left and hugged the side of the drain for four hundred carefully counted paces. Then he turned again at right angles but to the right this time, and was quickly swallowed up in the silence of a dead world.

Very, very soon it came to him, that he had lost a friend, for he realised now that the sullen gurgling of the water in the drain had been a comfort to him and a reassuring thought that he could turn back at any time if he so wished, and reach his car and safety again. But now he was cut off from everything, and in all directions, less than fifty yards away, stretched a wall of ghostly and impenetrable fog.

His life’s work among dangers had however, hardened him, and with no quickening of his pulses, and with the little compass held close up to his eyes all the time, he proceeded to walk briskly forward, to cover the two miles that the expoliceman had told him would now be separating him from the racing stables of the dead Jew, Bernstein.

“And once I’m there,” he thought confidently, “I shall be only 300 yards due east from the farm where they all live.”

He did not seem too happy, all the same. “But I may have to wait until dark,” his thoughts ran on, “and that will make it about half-past five. It’s quite on the cards, too, that those dogs may spoil everything, and it isn’t too good to think they may turn up when I’m too close to the buildings to dare to use my gun. Still, I should imagine that with this dense fog, they have been chained up long ago, for the sake of the sheep.”

He kept on looking round, however, and held his square yard of wire-netting unfolded, and the German bayonet ready in his hand. “But what a come down,” he grinned, assuring himself for the hundredth time of the sharpness of the blade. “Once making history in the great world-war, and now being hawked about upon a lonely fen, to thrust into the throat of a snarling dog if he comes near.”

The fog was lifting slightly, and his area of observation had now become a little wider. Then when, according to his calculations, he could not be more than a quarter of a mile from his objective, he took a zig-zag course for a hundred yards or so, to assure himself that his compass was functioning correctly. He found it was quite all right and was just setting his course due north again, when suddenly he heard a slight noise behind him.

He paused for a moment, thinking he might have been mistaken, but then he heard the sound again — the labored panting of some animal!

His blood froze in horror as he stood peering in the direction from which the sound was coming, but all was fog — fog everywhere, with earth and sky in the grip of their dark master.

Then suddenly a huge form, magnified by the vapor, loomed into view. “A calf! only a calf!” he ejaculated in great relief, “and I have been giving myself a fright for nothing.”

But in two seconds the horror all returned, for, with his head bent close to the ground, the creature was now nosing along each foot of the zig-zag course that the detective had just taken. To the left, to the right, and then to the left again, on came the animal.

“One of the Alsatians!” gasped Larose. “He’s picked up my trail!” and then he smiled, as a brave man often does in the presence of danger. His hand was steady, his pulse had quietened down, and he sank gently on to the ground in such a position that he would be lying upon his left side, and facing it, when the Alsatian had finished with the zig-zags and came to nose along the straight trail.

A few breathless seconds followed, with the hound quickening his pace and now beginning to whimper eagerly. Then he stopped suddenly and with his fine head upraised and one fore paw lifted off the ground, stood staring straight in front of him.

He had caught sight of Larose.

The detective was lying quite still. The square of wire netting was tucked under one side of him, covering his head and the greater part of his body. In his right hand he held the bayonet, and in his left, clutching to the wire netting, was his automatic.

Perhaps ten seconds then passed, and becoming aware, perhaps by some instinct or perhaps by some unconscious movement that Larose had made, that his prey before him was living and not dead, the great beast drew back his lips with a savage snarl, and then without an instant’s warning, dashed straight for the detective’s throat.

But with his head down, there was no force behind the impact, and with his muzzle coming in contact with the wire netting, he fixed his teeth in it and tore at it to pull it away.

But the deadly bayonet plunged instantly between the meshes of the wire and drew blood from somewhere in the dog’s head. The blow, however was not an effective one, and the enraged beast, snarling furiously in his pain, returned savagely to the attack, this time planting his great forefeet upon the detective’s shoulder and rolling him over upon his back.

But, like lightning, the bayonet plunged again, and now, penetrating deeply into the flesh, it tore a ghastly wound across the animal’s throat. The effect was instantaneous, and the Alsatian sank down groaning upon his side.

Larose sprang to his feet, and not discarding the wire netting, plunged the bayonet again and again, into the dog’s heart.

The whole happening had not lasted two minutes, from the moment when the detective had first seen the Alsatian to when he was kneeling down beside it and wiping his hands upon the damp grass.

But there was no exultation in his face. On the contrary, it was more gloomy and downcast. “But this is most unfortunate,” he thought, “for there’s no possible chance of hiding the body, and with the beast missing they’ll find it at once when the fog lifts and know that someone’s been here.” He shook his head. “It’s no triumph, it’s a real disaster.”

A few moments later, however, he was regarding it as a disaster of quite a minor kind, for, to his horror, he discovered he had now lost his compass.

In a fever of haste, he began to search all over the ground, where he had been standing when he had first heard the pantings behind him, where he had lain, awaiting the coming of the Alsatian and where, finally, he had sprung to plunge the bayonet into its heart.

At last he found it close to the dead dog’s side, trodden into the ground, its glass smashed to atoms and its needle broken off!

For a long moment he stood surveying it as he held it in the palm of his hand. Then he looked round at the fog, now beginning to close down thicker and thicker than ever, and a choking feeling came up into his throat. In all his life he thought he had never been in a more unpleasant position.

“Gilbert! Gilbert!” he exclaimed sorrowfully, “you’re losing grip of the game”— he looked down at the Alsatian —“and if this poor beast only knew it, he has triumphed even in death.”

But he was never down-hearted for very long, and, always of a sanguine disposition, he was very soon endeavoring to discern some way out of his predicament.

He tried, first, to place the exact position in which he had lain down, and from that determine in which direction the Alsatian had approached, for the path of the dog, he told himself, following in a bee-line up his own track, would point directly due north, and towards where the stables lay.

He worked it all out as well as he could, and then, to make sure he should not wander in a circle, walked forward in distances of only ten paces at a time, and after the first ten paces, with two directing ground-marks always behind him.

The procedure was very simple. He dropped his cap, covered the ten paces, stuck his bayonet into the ground, and then went on for another, ten, but walking backwards this time in order to keep the cap and bayonet always exactly in the same straight line. Then he dropped his piece of wire netting, went back and retrieved the cap, and using the bayonet and wire netting now for the straight line, walked backwards as before for another ten paces and dropped his cap once more.

It was very slow work, and he was by no means too hopeful about it, but it was the only thing he could think of, and all along he kept buoying himself up with the hope that with the fog lifting any moment he might catch sight of the disused stables, not far away, and perhaps be able to hide himself until night fell and the other Alsatian was chained up. Then circumstances must determine what he must do.

Larose walked on and on, but nothing happened and no building came into sight, just fog, impenetrable fog everywhere, and the ghostly silence of the lonely fen. Then at last, when he knew he must have proceeded much farther than the allotted quarter of mile — he realised that he was lost.

He heaved a big sigh, and sitting down, proceeded to light a cigarette. “No good worrying,” he told himself, “and no good tiring myself out”— he grinned —“I’ll just wait until the tea bell rings and then walk in with the farm hands. They can’t refuse me a good meal, even if they do shoot me afterwards.”

An hour passed, two, a weak and bastard dusk crept down and seemed to argue with the fog as to which was the better blanket, and then night fell, so chilling to the very marrow of his bones and so dark that it could almost be felt.

“But this won’t do,” he told himself, “or I’ll be getting another fever,” and he began to walk backwards and forwards, jerking his arms about all the time.

Then suddenly he was electrified by a muffled sound that came out of the darkness just upon his right, and his heart stood still in his excitement, for it had sounded like the banging of a door.

It was not repeated, but because there was not a breath of air stirring anywhere to make noises of its own accord, it came to him instantly that he was in the close vicinity of some animate beings, and most probably, for surely it was hardly likely to be otherwise, of human ones.

So he plucked up heart at once, and before he had lost the direction of the sound, plunged boldly into the darkness before him. Then came one of the minor shocks of the day, for he had not proceeded fifty paces when he banged right into a hard wall. For a moment the impact made him feel sick, but in a few seconds he had pulled his torch out and was inspecting what had brought him up so dead.

Yes, it was a stone wall, and higher than he could flash the rays of his torch; he knew it must be the racing stables that all along he had been making his objective. But how cruel Fortune had been, for these two hours and more he had been pacing up and down, less than forty yards away from the very spot he had come so far and through such danger to visit!

But he must be careful, very careful, he told himself, for a banged door meant the presence of someone, and evidently then the stables were not uninhabited, as the expoliceman had said.

Flashing his torch every few yards, he began circling cautiously round the building. He had struck the end of it, he found, for a very few yards’ progress brought him to a corner. Then he crept along the side, and, a very little way down, a light from an upper window attracted his attention. He could just see the window sill, and the window was square, and from the interruptions in the rays, he thought it must be a barred one. H............