The two men looked at one another in silence.

"Well?" said the Commissioner at last.

Tarling shook his head.

"That's amazing," he said, and looked at the little slip of paper between his finger and thumb.

"You see why I am bringing you in," said the Commissioner. "If there is a Chinese end to this crime, nobody knows better than you how to deal with it. I have had this slip translated. It means 'He brought this trouble upon himself.'"

"Literally, 'self look for trouble,'" said Tarling. "But there is one fact which you may not have noticed. If you will look at the slip, you will see that it is not written but printed."

He passed the little red square across the table, and the Commissioner examined it.

"That's true," he said in surprise. "I did not notice that. Have you seen these slips before?"

Tarling nodded.

"A few years ago," he said. "There was a very bad outbreak of crime in Shanghai, mostly under the leadership of a notorious criminal whom I was instrumental in getting beheaded. He ran a gang called 'The Cheerful Hearts'--you know the fantastic titles which these Chinese gangs adopt. It was their custom to leave on the scene of their depredations the _Hong_, or sign-manual of the gang. It was worded exactly as this slip, only it was written. These visiting cards of 'The Cheerful Hearts' were bought up as curios, and commanded high prices until some enterprising Chinaman started printing them, so that you could buy them at almost any stationer's shop in Shanghai--just as you buy picture post-cards."

The Commissioner nodded.

"And this is one of those?"

"This is such a one. How it came here, heaven knows," he said. "It is certainly the most remarkable discovery."

The Commissioner went to a cupboard, unlocked it and took out a suit-case, which he placed upon the table and opened.

"Now," said the Commissioner, "look at this, Tarling."

"This" was a stained garment, which Tarling had no difficulty in recognising as a night-dress. He took it out and examined it. Save for two sprays of forget-me-nots upon the sleeves it was perfectly plain and was innocent of lace or embroidery.

"It was found round his body, and here are the handkerchiefs." He pointed to two tiny squares of linen, so discoloured as to be hardly recognisable.

Tarling lifted the flimsy garment, with its evidence of the terrible purpose for which it had been employed, and carried it to the light.

"Are there laundry marks?"

"None whatever," said the Commissioner.

"Or on the handkerchiefs?"

"None," replied Mr. Cresswell.

"The property of a girl who lived alone," said Tarling. "She is not very well off, but extremely neat, fond of good things, but not extravagant, eh?"

"How do you know that?" asked the Commissioner, surprised.

Tarling laughed.

"The absence of laundry marks shows that she washes her silk garments at home, and probably her handkerchiefs also, which places her amongst the girls who aren't blessed with too many of this world's goods. The fact that it is silk, and good silk, and that the handkerchiefs are good linen, suggests a woman who takes a great deal of trouble, yet whom one would not expect to find over-dressed. Have you any other clue?"

"None," said the Commissioner. "We have discovered that Mr. Lyne had rather a serious quarrel with one of his employees, a Miss Odette Rider----"

Tarling caught his breath. It was, he told himself, absurd to take so keen an interest in a person whom he had not seen for more than ten minutes, and who a week before was a perfect stranger. But somehow the girl had made a deeper impression upon him than he had realised. This man, who had spent his life in the investigation of crime and in the study of criminals, had found little time to interest himself in womanhood, and Odette Rider had been a revelation to him.

"I happen to know there was a quarrel. I also know the cause," he said, and related briefly the circumstances under which he himself had met Thornton Lyne. "What have you against her?" he said, with an assumption of carelessness which he did not feel.

"Nothing definite," said the Commissioner. "Her principal accuser is the man Stay. Even he did not accuse her directly, but he hinted that she was responsible, in some way which he did not particularise, for Thornton Lyne's death. I thought it curious that he should know anything about this girl, but I am inclined to think that Thornton Lyne made this man his confidant."

"What about the man?" asked Tarling. "Can he account for his movements last night and early this morning?"

"His statement," replied the Commissioner, "is that he saw Mr. Lyne at his flat at nine o'clock, and that Mr. Lyne gave him five pounds in the presence of Lyne's butler. He said he left the flat and went to his lodgings in Lambeth, where he went to bed very early. All the evidence we have been able to collect supports his statement. We have interviewed Lyne's butler, and his account agrees with Stay's. Stay left at five minutes past nine, and at twenty-five minutes to ten--exactly half an hour later--Lyne himself left the house, driving his two-seater. He was alone, and told the butler he was going to his club."

"How was he dressed?" asked Tarling.

"That is rather important," nodded the Commissioner. "For he was in evening dress until nine o'clock--in fact, until after Stay had gone--when he changed into the kit in which he was found dead."

Tarling pursed his lips.

"He'd hardly change from evening into day dress to go to his club," he said.

He left Scotland Yard a little while after this, a much puzzled man. His first call was at the flat in Edgware Road which Odette Rider occupied. She was not at home, and the hall porter told him that she had been away since the afternoon of the previous day. Her letters were to be sent on to Hertford. He had the address, because it was his business to intercept the postman and send forward the letters.

"Hillington Grove, Hertford."

Tarling was worried. There was really no reason why he should be, he told himself, but he was undoubtedly worried. And he was disappointed too. He felt that, if he could have seen the girl and spoken with her for a few minutes, he could have completely disassociated her from any suspicion which might attach. In fact, that she was away from home, that she had "disappeared" from her flat on the eve of the murder, would be quite enough, as he knew, to set the official policeman nosing on her trail.

"Do you know whether Miss Rider has friends at Hertford?" he asked the porter.

"Oh, yes, sir," said the man nodding. "Miss Rider's mother lives there."

Tarling was going, when the man detained him with a remark which switched his mind back to the murder and filled him with a momentary sense of hopeless dismay.

"I'm rather glad Miss Rider didn't happen to be in last night, sir," he said. "Some of the tenants upstairs were making complaints."

"Complaints about what?" asked Tarling, and the man hesitated.

"I suppose you're a friend of the young lady's, aren't you?" and Tarling nodded.

"Well, it only shows you," said the porter confidentially, "how people are very often blamed for something they did not do. The tenant in the next flat is a bit crotchety; he's a musician, and rather deaf. If he hadn't been deaf, he wouldn't have said that Miss Rider was the cause of his being wakened up. I suppose it was something that happened outside."

"What did he hear?" asked Tarling quickly, and the porter laughed.

"Well, sir, he thought he heard a shot, and a scream like a woman's. It woke him up. I should have thought he had dreamt it, but another tenant, who also lives in the basement, heard the same sound, and the rum thing was they both thought it was in Miss Rider's flat."

"What time was this?"

"They say about midnight, sir," said the porter; "but, of course, it couldn't have happened, because Miss Rider had not been in, and the flat was empty."

Here was a disconcerting piece of news for Tarling to carry with him on his railway journey to Hertford. He was determined to see the girl and put her on her guard, and though he realised that it was not exactly his duty to put a suspected criminal upon her guard, and that his conduct was, to say the least of it, irregular, such did not trouble him very much.

He had taken his ticket and was making his way to the platform when he espied a familiar figure hurrying as from a train which had just come in, and apparently the man saw Tarling even before Tarling had recognised him, for he turned abruptly aside and would have disappeared into the press of people had not the detective overtaken him.

"Hullo, Mr. Milburgh!" he said. "Your name is Milburgh, if I remember aright?"

The manager of Lyne's Store turned, rubbing his hands, his habitual smile upon his face.

"Why, to be sure," he said genially, "it's Mr. Tarling, the detective gentleman. What sad news this is, Mr. Tarling! How dreadful for everybody concerned!"

"I suppose it has meant an upset at the Stores, this terrible happening?"

"Oh, yes, sir," said Milburgh in a shocked voice. "Of course we closed the Store for the day. It is dreadful--the most dreadful thing within my experience. Is anybody suspected, sir?" he asked.

Tarling shook his head.

"It is a most mysterious circumstance, Mr. Milburgh," he said. And then: "May I ask if any provision had been made to carry on the business in the event of Mr. Lyne's sudden death?"

Again Milburgh hesitated, and seemed reluctant to reply.

"I am, of course, in control," he said, "as I was when Mr. Lyne took his trip around the world. I have received authority also from Mr. Lyne's solicitors to continue the direction of the business until the Court appoints a trustee."

Tarling eyed him narrowly.

"What effect has this murder had upon you personally?" he asked bluntly. "Does it enhance or depreciate your position?"

Milburgh smiled.

"Unhappily," he said, "it enhances my position, because it gives me a greater authority and a greater responsibility. I would that the occasion had never arisen, Mr. Tarling."

"I'm sure you do," said Tarling dryly, remembering Lyne's accusations against the other's probity.

After a few commonplaces the men parted.

Milburgh! On the journey to Hertford Tarling analysed that urbane man, and found him deficient in certain essential qualities; weighed him and found him wanting in elements which should certainly form part of the equipment of a trustworthy man.

At Hertford he jumped into a cab and gave the address.

"Hillington Grove, sir? That's about two miles out," said the cabman. "It's Mrs. Rider you want?"

Tarling nodded.

"You ain't come with the young lady she was expecting?" said the driver

"No," replied Tarling in surprise.

"I was told to keep my eyes open for a young lady," explained the cabman vaguely.

A further surprise awaited the detective. He expected to discover that Hillington Grove was a small suburban house bearing a grandiose title. He was amazed when the cabman turned through a pair of impressive gates, and drove up a wide drive of some considerable length, turning eventually on to a gravelled space before a large mansion. It was hardly the kind of home he would have expected for the parent of a cashier at Lyne's Store, and his surprise was increased when the door was opened by a footman.

He was ushered into a drawing-room, beautifully and artistically furnished. He began to think that some mistake had been made, and was framing an apology to the mistress of the house, when the door opened and a lady entered.

Her age was nearer forty than thirty, but she was still a beautiful woman and carried herself with the air of a grand dame. She was graciousness itself to the visitor, but Tarling thought he detected a note of anxiety both in her mien and in her voice.

"I'm afraid there's some mistake," he began. "I have probably found the wrong Mrs. Rider--I wanted to see Miss Odette Rider."

The lady nodded.

"That is my daughter," she said. "Have you any news of her? I am quite worried about her."

"Worried about her?" said Tarling quickly. "Why, what has happened? Isn't she here?"

"Here?" said Mrs. Rider, wide-eyed. "Of course she is not."

"But hasn't she been here?" asked Tarling. "Didn't she arrive here two nights ago?"

Mrs. Rider shook her head.

"My daughter has not been," she replied. "But she promised to come and spend a few days with me, and last night I received a telegram--wait a moment, I will get it for you."

She was gone a few moments and came back with a little buff form, which she handed to the detective. He looked and read:

"My visit cancelled. Do not write to me at flat. I will communicate with you when I reach my destination."

The telegram had been handed in at the General Post Office, London, and was dated nine o'clock--three hours, according to expert opinion, before the murder was committed!