At Armfield's Gerald learned but little more.

Nothing had been seen of Depew there after eleven o'clock on the morning of his leaving. His bags he had taken away to the station, paid his bill, and had said he was not sure whether he would sleep there or at Liverpool that night.

There was a small hand bag still at the hotel, containing a shirt, collars, and handkerchiefs—nothing more.

That left Finsbury Circus for Gerald to investigate.

He remembered the names of Lennox, and looked at his short cuff whereon he had penciled the numbers of the houses from the directory.

He saw the letters on the wire blind which had attracted Todd, "Painless Dentistry"; and he remembered what Todd had said in the letter to his wife about the extraction of his tooth.

He went further and saw a brass plate—"Arthur Lennox, M.R.C.S." This determined him.

He believed in his power of reading faces, and he was eager to try his hand at the doctor's.

He entered the house, and went to the surgeon's door. Knocked and knocked again; and again.

Then he pulled the housekeeper's bell.

In reply to his inquiries he learned that Mr. Arthur Lennox was away abroad; had gone—he tallied the date—the day the Europia sailed with Todd's body aboard.

Further information, the housekeeper told him, could be obtained of the surgeon's brother—a dentist, a few doors off.

Gerald felt that at last he was nearing his goal.

"Ah! I don't want to see the dentist," he said. "I don't know him. I was very friendly with the doctor, and I promised to see him when I came to England. I wasn't quite sure, though, that I had the address correct—indeed, I am not now sure that this Dr. Lennox is the one I want. What sort of a man is he?"

The housekeeper described him. And at each detail of the description Gerald's hopes rose higher and higher.

For she was describing the man who had been found with his throat cut, the man whose newspaper picture Gerald had then in his coat pocket.

He withdrew that from his pocketbook, and handing it to the housekeeper, said:

"Is that anything like him?"

"Oh, yes," answered the housekeeper in a moment; "there is no mistaking it. That's he right enough."

"Then I haven't made any mistake after all. Thank you for——"

"There goes his brother if you want to see him," interposed the housekeeper hurriedly. "He goes home about this time—they used both to leave at five o'clock."

"No, thank you," answered Gerald; "I am obliged to you. Good-day;" and he went down the steps.

"The dentist has gone," he muttered. "I'll just look at his show now, and interview him to-morrow. A night's thought on this won't do any harm. There's such a thing as being in too great a hurry. More haste, less speed."

He entered the house in which the dentist had rooms.

As he stood looking at the door, it opened, and a boy started to come out.

"Good-afternoon," said Gerald cheerfully, and walking in. "Is it too late to have a tooth seen to?"

"Just too late, sir," replied the boy Sawyer; "Guv'nor's just gone. He'll be here at ten o'clock in the morning—if he's well enough."

"I'm sorry. Do you mind my sitting down and resting for just a minute or two? I hurried here so fast for fear of missing him, that it set my heart beating dangerously fast."

"Not at all, sir."

"I was recommended here by an American gentleman, a friend of mine."

"Oh, sir."

"Yes. Some while ago he came here—one afternoon—and had a tooth out, and spoke so well of the job that I determined to come here myself."

"Yes, sir."

"He had a tooth extracted painlessly."

"Yes, sir, lots of people has 'em out that way."

"How is it done—chloroform?"

"Bless you, no sir! With the gas."

"Is it dangerous at all?"

"Lor no, sir. 'Sides, there's always a doctor present to help."

"Really?"

"Yes. The guv'nor used to have his brother in to do it before he went abroad."

"Has rooms some doors off, hasn't he?"

"Yes, that's him, sir."

"Has he been abroad long?"

"Been away just—well, that's curious, sir, as you mentioned an American gent. I haven't seen the doctor since the day the last American gent came here."

"That is very funny. Very likely, too, it happened to be my friend. Do you remember him?"

"Rather, sir. We don't have too many patients here"—with a grin—"as I can't remember em."

"You would know him again if you saw him?"

"Rather."

"Is that like him?"

Gerald handed the boy the daguerreotype of Todd as he spoke.

"Like him!" said the boy; "it is him."

"That certainly is a curious thing. My American friend was a bit of a coward, you know. I guess he made a big fuss about having his tooth pulled. Did he call out in any pain?"

"I don't know."

"I thought you said——"

"You see I minded both places. When your American friend came in and said he wanted the gas, I was sent in for the doctor, and minded his place for him when he came in here."

"I see."

"When I came back, of course your friend had gone."

"Hadn't, I suppose, fallen asleep on the couch or in the operating chair, had he?"

"No. I said had gone."

"So you did—I thought perhaps you might have overlooked him."

"Not much. I have to put away the things tidily, and I shouldn't overlook much."

"My American friend described to me the chair he sat in—operating chair, don't they call it?"

"Yes, that's it."

"As being a very curious one—is it?"

"Nothing out of the common. This is it."

He opened the inner door as he spoke, and Gerald entered.

"You were right about not overlooking him. If he had been here you must have seen him."

"Yes."

"This cupboard would have held him, though."

"Yes," replied the boy, with a grin. "It is big enough; but we don't stick patients into cupboards, you know."

Gerald laughed heartily at the joke.

"Well," he said, "my heart's quiet enough, now, thanks. I am much obliged to you for letting me rest. I'll come in and see the dentist to-morrow."

"If he's well enough to come to business, he'll be pleased to see you."

"Ill, is he?"

"Yes, sir. Has been for some weeks, ever since his brother went away."

"That's curious."

"Yes, sir. Shall I make an appointment for you to-morrow, sir?"

"Yes; you can say I'll be here at eleven o'clock sharp."

"Right you are, sir; he'll keep the appointment right enough if he can. He won't fail."

"Nor shall I."

"Good-evening, sir."

"Good-evening."

Down the steps went Gerald, down into the Circus.

He felt more pleased with himself than he had felt for a long while. He was on the right scent now, he was sure.

To-morrow at eleven he must assume once more the guise of the New York detective. The appointment was eleven o'clock. Gerald would not fail to keep it.