The next morning, contrary to Fuller's expectations, Ashton-Kirk did not start out on a fresh trail. The discovery, as developed the night before, was so curious that the young man was quite sure that it would immediately lead to more surprising revelations. So he was greatly astonished when he reached the old-fashioned house to learn from Stumph that the secret agent had gone into the country.

"He took his fishing rods," explained Stumph, "and went to Jordan's Mills. He said he'd be back to-morrow."

"He's gone down there to think things out," Fuller told himself, other occasions of the same sort fresh in his mind. "A pipe, a green bank under a tree, and a painted float to watch, are fine things to make thoughts run. They just seem to drift along with the current."

Sure enough, the next afternoon Ashton-Kirk came back; there was a keen, vigorous look about him that told of a freshening such as his aide had pictured. He heard what Burgess had to say regarding his hunt for Karkowsky as soon as he arrived, for the man was waiting for him.

"He's gone completely, so far as I can make out," the broad-shouldered man informed him. "There's not a trace to be found in any direction. I've questioned everybody I could find in the section who was acquainted with him, but they knew only his name and thought him a pretty good sort of fellow."

Ashton-Kirk said little in reply; but his manner showed that he was far from satisfied. After dinner he smoked and walked about his study. Then he went to his room.

A half hour later a tall, cadaverous-looking person, in a black coat and with a silk hat, the nap of which was well worn, came down the stairs. To Stumph he said:

"I shall be back in a few hours, perhaps. But should any one call, say that I will see him in the morning."

"Very well, sir," said Stumph, gravely.

It was just fading from the late twilight to the early shadows of evening when the cadaverous man turned the corner and headed toward Fourth Street. His shoulders were bent and his gait was shuffling; the thread gloves which he wore were broken in places here and there and the black coat was a trifle short in the sleeves.

But he attracted little or no attention, for in that neighborhood shabby characters were frequent enough. When once he got into his stride it was astonishing to see how he covered the ground, for all the shuffle. At Fourth Street and Corinth Avenue he halted and looked about.

It was now dark; the street lights were throwing their pale blue rays into the hidden corners of the dirty highways; upon stoop and cellar doors, throngs of soiled-looking men and women were congregated; hordes of children were all about, and their cries were shrill and incessant.

"Brekling?" said a man with a peddler's cart. "Oh, yes, his place is there on the corner."

A yellow gaslight burned dimly in the harness shop when the man in the worn top hat entered. There was a heavy smell of leather and oil; the floor was littered with scraps, and the broken parts of many sets of harness were stacked up in the rear. A small man with round spectacles and a dirty apron came forward; he had been reading a Polish newspaper under the dim light.

"Well, sir," said he, inquiringly, and with a marked accent, "what can I do for you this evening?"

"You have rooms to rent, I believe," said the other in a shaky sort of voice.

Instantly the small man was all attention. He put down his newspaper and beamed through his glasses at the stranger.

"I have one room," said he. "It is on the third floor, but it is a good room and well furnished. Will you look at it?"

"Yes, if you please," quavered the man with the bent shoulders.

The little harness-maker lighted a candle and led the way to a staircase at the side which opened into the street. A troop of children had possession of it and their shrill outcries as they ran up and down were deafening. Like a fury the Pole ran among them, scattering them right and left.

"But they are good children," he told the prospective tenant, "and they make very little noise."

The room was small and had a window opening upon a court; the furniture was scant and the floor was bare.

"Once," confessed the little harness-maker, "I had a carpet for it; but there were so many holes in it at last, that I took it up. Some day," hopefully, "I shall get another."

The other gave a glance about.

"I shall take it—if it is not too much."

"Six dollars a month is not too much," said the tradesman landlord. "It is worth more."

"I'll give you five," stated the other, in his shaky voice.

The Pole gestured his despair; the candle went up and down and the two huge shadows jigged grotesquely upon the wall.

"It is worth six," he said. "The last tenant paid that much without a word."

"He was rich," suggested the other. "No one but a man of means would pay that."

"He was not rich," protested Brekling. "He was as poor as a rat. I know that, for he was a countryman of mine, and there are no rich Poles."

The man with the bent shoulders counted out five dollars in small coin upon a table.

"I will pay a month in advance," said he.

The little man looked at the pile of silver for a moment; unable to resist, he said:

"Very well, I will take it. But the room is worth more."

He scraped up the money and put it away in his pocket; the other took off his hat and laid it upon the table and looked about with the manner of a man at home.

"Have you any other lodgers?" he asked.

"There are three families on the floor below, and then there are a few mechanics on this. But they are all decent people," earnestly. "Sometimes they take a little too much, but not often. You will find that they are quiet enough." Then after a look at his new tenant, "You will move in at once?"

"To-morrow. And now, if you don't mind, I should like to be left alone."

"Of course," said the little harness-maker. "Of course."

And so he went out and down the stairs to his shop. If he had been a curious man and had loitered on the landing and put his eye to the keyhole, he would have witnessed an unusual sight. For the door had no sooner closed behind him than the cadaverous-looking man altered in appearance like an enchanted prince in a fairy-tale. The bent shoulders disappeared, the tread as he moved swiftly about the room was firm and noiseless, the face became keen and resolute, the eyes alert and eager. He drew off the long black coat and with sleeves tucked up began a searching examination of the room. The closet, the bureau, the wash-stand came first; then the edges of the floor. The contents of a small sheet-iron stove were dragged out; amid the coal ash was much burnt paper, but apparently nothing that brought the searcher any reward. After about an hour, he stood in the center of the room, defeated.

"Friend Karkowsky is a careful man," he muttered. "There is not a scrap of anything."

He put on his coat and hat and left the room. Once outside the door, the shuffle reappeared in his gait, the cadaverous look returned, and the shoulders bent wearily. In the shop, the harness-maker was once more engaged with the Polish newspaper; he looked up as his new tenant came in.

"Your last lodger was not careful," complained the latter in his shaky voice. "The room is in quite a state."

"But I will fix it," announced the Pole accommodatingly. "I always treat my lodgers right; never has one complained. But I often had to complain. Now, that same man—the one that had your room last—gave me much trouble. Would you believe it, the police came at last!"

"Ah, yes. He was a disturber."

"No, no. Indeed, he was very quiet. Even when the other lodgers made a noise he did not get mad. The only person he ever quarreled with was Jackson."

"And who is Jackson?"

"He is the postman. It was something about letters that they fought over. Once Karkowsky called the letter man a dunce. But Jackson only laughed."

An hour later, in his study, Ashton-Kirk took down the telephone receiver and asked for a certain number. When he was connected he asked:

"Is that Postal Station Seven?"

"It is," came the reply.

"Can you give me the address of Postman Jackson, attached to that station?"

"No. But I can tell you where you can get him if you want him to-night."

"I'll be obliged to you."

"Call up Wonderleigh's place; he's sure to be there at this hour, playing pinochle in the back room. The number's 35-79 Parkside."

In a few moments the secret agent had Mr. Jackson on the wire.

"I want to speak to you about Karkowsky, lately on your route," said he.

There was a laugh at the other end; then the postman answered:

"This ain't the police?"

"Not exactly, but something of the sort."

"Well, I've kind of expected that somebody would ask me about that old scout; they seem to have asked everybody else."

"Would you mind telling me about the trouble you had with him regarding some letters?"

"Oh, that! Sure. You see, Karkowsky for the first while that he lived at Brekling's place received a letter a couple of times a week that always got my attention. It was in a woman's writing—kind of a foreign writing that was mighty hard to make out. It was always a brown, square envelope, and it was always post-marked at Central Station. I couldn't tell you all this about most of the letters I handle, but this one gave me so much trouble at first finding out what the address was that I knew it by heart.

"One day I handed one of them to Karkowsky, and he threw it back at me.

"'That's not for me,' he said. And sure enough it wasn't. It was for another party a couple of blocks away—a party that was new to my route. This same mistake happened a couple of times—me being so used to the letters that I never looked at 'em twice—and every time old Karkowsky got his back up. One day I kidded him about losing his girl and said I guessed some other fellow had won her out, seeing that he was getting all the letters, and Karkowsky swore. He called me some hard names that day and threatened to report me. So I cut out the jokes."

"When the letters began arriving for the second person they ceased for Karkowsky?"

"Right away. He never got another one."

There was a moment's silence; then the secret agent asked:

"Can you recall this other person's name?"

"Oh, yes. It's Kendreg. He lives on the top floor of 424 Lowe Street."

After Ashton-Kirk had hung up he sat for a few moments, a peculiar expression on his face. Then he pressed one of the row of buttons. While awaiting a response, he penciled a few lines upon a tablet; when Fuller came in he tore off the sheet and handed it to him.

"Give this to Burgess," he requested. "Have him look this person up quietly. Tell him to work under cover as much as possible; and to especially note if he has any women visitors."

"Very well," said Fuller; and turning he left the room.