Mr. Ingles leant forward in his chair.

"Four men have tried in the last four years," he said slowly; "men of character, and honesty, and brain power. Any one of them might in time have interfered with his plans." He paused.

"Well? "I queried. 

"Well. they are dead. One wrote an article, and mentioned Li Chang Yen's name in connection with the riots in Pekin, and within two days he was stabbed in the street. His murderer was never caught. The offences of the other two were similar. In a speech or an article, or in conversation, each linked Li Chang Yen's name with rioting or revolution and within a week of his indiscretion each was dead. One was poisoned; one died of cholera, an isolated case-not part of an epidemic; and one was found dead in his bed. The cause of the last death was never determined, but I was told by a doctor who saw the corpse that it was burnt and shrivelled as though a wave of electrical energy of incredible power had passed through it."

"And Li Chang Yen?" inquired Poirot. "Naturally nothing is traced to him, but there are signs, eh?"

Mr. Ingles shrugged.

"Oh, signs-yes, certainly. And once I found a man who would talk, a brilliant young Chinese chemist who was a protege of Li Chang Yen's. He came to me one day, this chemist, and I could see that he was on the verge of a nervous breakdown. He hinted to me of experiments on which he'd been engaged in Li Chang Yen's palace under the mandarin's direction-experiments on coolies in which the most revolting disregard for human life and suffering had been shown. His nerve had completely broken, and he was in the most pitiable state of terror. I put him to bed in a top room of my own house, intending to question him the next day-and that, of course, was stupid of me."

"How did they get him?" demanded Poirot.

"That I shall never know. I woke that night to find my house in flames, and was lucky to escape with my life. Investigation showed that a fire of amazing inten5 sity had broken out on the top floor, and the remains of my young chemist friend were charred to a cinder."

I could see from the earnestness with which he had been speaking that Mr. Ingles was a man mounted on his hobby horse, and evidently he, too, realised that he had been carried away, for he laughed apologetically.

"But, of course," he said, "I have no proofs, and you, like the others, will merely tell me that I have a bee in my bonnet."

"On the contrary," said Poirot quietly, "we have every reason to believe your story. We ourselves are more than a little interested in Li Chang Yen."

"Very odd your knowing about him. Didn't fancy a soul in England had ever heard of him. I'd rather like to know how you did come to hear of him-if it's not indiscreet."

"Not in the least, monsieur. A man took refuge in my rooms. He was suffering badly from shock, but he managed to tell us enough to interest us in this Li Chang Yen. He described four people-the Big Four-an organisation hitherto undreamed of. Number One is Li Chang Yen, Number Two is an unknown American, Number Three an equally unknown Frenchwoman, Number Four may be called the executive of the organisation-/Ae destroyer. My informant died. Tell me, monsieur, is that phrase known to you at all? The Big Four."

"Not in connection with Li Chang Yen. No, I can't say it is. But I've heard it, or read it, just lately-and in some unusual connection too. Ah, I've got it."

He rose and went across to an inlaid lacquer cabinet -an exquisite thing, as even I could see. He returned with a letter in his hand.

"Here you are. Note from an old sea-faring man I ran against once in Shanghai. Hoary old reprobate-maudlin with drink by now, I should say. I took this to be the ravings of alcoholism."

He read it aloud:-

"dear sir,-You may not remember me, but you did me a good turn once in Shanghai. Do me another now. I must have money to get out of the country. I'm well hid here, I hope, but any day they may get me. The Big Four, I mean. It's life or death. I've plenty of money, but I daren't get at it, for fear of putting them wise. Send me a couple of hundred in notes. I'll repay it faithful-I swear to that.-Your servant, sir,

"jonathan whalley.'' "Dated from Granite Bungalow, Hoppaton, Dartmoor.

I'm afraid I regarded it as rather a crude method of relieving me of a couple of hundred which I can ill spare. If it's any use to you-" He held it out.

"Je vous remercie, monsieur. I start for Hoppaton a I'heure memo."

"Dear me, this is very interesting. Supposing I came along too? Any objection?"

"I should be charmed to have your company, but we must start at once. We shall not reach Dartmoor until close on nightfall, as it is."

John Ingles did not delay us more than a couple of minutes, and soon we were in the train moving out of Paddington bound for the West Country. Hoppaton was a small village clustering in a hollow right on the fringe of the moorland. It was reached by a nine-mile drive from Moretonhamstead. It was about eight o'clock when we arrived; but as the month was July, the daylight was still abundant.

We drove into the narrow street of the village and then stopped to ask our way of an old rustic.

"Granite Bungalow," said the old man reflectively,

"it be Granite BungaW you do want? Eh?"

We assured him that this was what we did want.

The old man pointed to a small gray cottage at the end of the street.

"There be ('Bungalow. Do yee want to see t'lnspector?"

"What Inspector?" asked Poirot sharply; "what do you mean?"

"Haven't yee heard about t'murder, then? A shocking business t'was seemingly. Pools of blood, they do say."

"Mow Dieu!" murmured Poirot. "This Inspector of yours, I must see him at once.''

Five minutes later we were closeted with Inspector Meadows. The Inspector was inclined to be stiff at first, but at the magic name of Inspector Japp of Scotland Yard, he unbent.

"Yes, sir; murdered this morning. A shocking business.

They 'phoned to Moreton, and I came out at once.

Looked a mysterious thing to begin with. The old man -he was about seventy, you know, and fond of his glass, from all I hear-was lying on the floor of the living-room. There was a bruise on his head and his throat was cut from ear to ear. Blood all over the place, as you can understand. The woman who cooks for him, Betsy Andrews, she told us that her master had several little Chinese jade figures, that he'd told her were very valuable, and these had disappeared. That, of course, looked like assault and robbery; but there were all sorts of difficulties in the way of that solution. The old fellow had two people in the house; Betsy Andrews, who is a Hoppaton woman, and a rough kind of manservant, Robert Grant. Grant had gone to the farm to fetch the milk, which he does every day, and Betsy had stepped out to have a chat with a neighbour. She was only away twenty minutes-between ten and half-past-and the crime must have been done then. Grant returned to the house first. He went in by the back door, which was open-no one locks up doors round here-not in broad daylight, at all events-put the milk in the larder, and went into his own room to read the paper and have a smoke. Had no idea anything unusual had occurred-at least, that's what he says. Then Betsy comes in, goes into the living-room, sees what's happened, and lets out a screech to wake the dead. That's all fair and square.

Some one got in whilst those two were out, and did the poor old man in. But it struck me at once that he must be a pretty cool customer. He'd have to come right up the village street, or creep through some one's back yard. Granite Bungalow has got houses all round it, as you can see. How was it that no one had seen him?"

The Inspector paused with a flourish.

"Aha, I perceive your point," said Poirot. "To continue?"