A man of middle age, muffled up in an overcoat, got out of a Third Avenue car, just opposite a small drug shop. Quickly glancing up and down the street with a furtive look, as if he wished to avoid recognition from any passerby who might know him, he entered the shop.

It was a small shop, not more than twelve feet wide by eighteen deep. The only person in attendance was a young man approaching thirty years of age, his eyes and hair very light, and his features small and insignificant. He was the druggist's clerk, working on a small salary of ten dollars a week, and his name was James Cromwell.

He came forward as the person first named entered the shop.

"How can I serve you, sir?" he inquired in a respectful voice.

The person addressed drew from his pocket a piece of paper on which a name was inscribed.

"I want that," he said; "do you happen to have it?"

The shopman's face was tinged with a slight color as he read the name inscribed on the paper.

"You are aware, I suppose, that this is a subtle poison?" he said, interrogatively.

"Yes," said the other, in a tone of outward composure, "so I understand from the friend who desired me to procure it for him. Have you it, or shall I have to go elsewhere?"

"Yes; we happen to have it by the merest chance, although it is rather a rare drug in the materia medica. I will get it for you at once."

The customer's face assumed an air of satisfaction as the clerk spoke, and he sat down on a stool in front of the counter.

James Cromwell quickly placed a small parcel in his hands, and the customer, drawing out a pocketbook, which appeared to be well-filled, paid for his purchase.

He then walked out of the shop, and to the corner of the street, where he waited for an uptown car. As he left the shop, a ragged boy of ten, with a sharp, weazened face entered.

"I want an ounce of carmels," he said.

"Wait a minute; do you want to earn a quarter?" demanded the shopman, abruptly.

"I reckon I do," answered the urchin.

"Then you must follow the gentleman who just went out of the shop: find out where he lives, and what his name is. Come out, and I will point him out to you."

Just outside of the door, James Cromwell cast his eyes up the street and saw his late customer in the act of jumping on board a Fourth Avenue car.

"There he is," he said, hastily pointing him out to the boy. "You will have to ride, too. Can you catch that car?"

"I've got no money," said the boy.

"Here's a quarter. Now run."

"But I'm to have a quarter besides?"

"Yes, yes. Make haste."

The boy ran forward, and succeeded in overtaking the car and clambering on board.

"Look here, young chap," said the conductor, suspiciously, "have you got any money to pay your fare?"

"Yes, I have," said the boy. "Don't you be afraid, old hoss."

"Show your money, then."

The boy produced the quarter which had just been given him.

"You're richer than I supposed," said the conductor. "Here's your change."

The boy put back the twenty-two cents remaining in the pocket of his ragged pants, and began to look about him for the passenger whom he was required to track. The latter was seated on the left hand side, four seats from the door.

"I wonder why I'm to foller him about," said the boy to himself. "Maybe he's run off without paying his bill. Anyway, it's nothing to me as long as I earn a quarter. It'll pay me into the Old Bowery to-night."

And the boy began to indulge in pleasing anticipations of the enjoyment he would receive from witnessing the great spectacle of the "Avenger of Blood," which was having a successful run at the favorite theatre with boys of his class.

Before proceeding, I may mention that the boy referred to was known as Hake, a name whose derivation I have been unable to learn. He had been a street vagrant for half his life, and was precocious in his knowledge of metropolitan life in its lowest phases.

If the gentleman whom he was employed to watch noticed the ragged boy, he hadn't the remotest suspicion that there was the least connection between them, or that his being there had anything to do with his own presence in the car. He took out a paper from his pocket and began to read.

"I wonder how far I've got to go," thought Hake. "If it's far I'll have to ride back, and that'll take three cents more."

He reflected, however, that nineteen cents would remain, and he would besides have the quarter which had been promised him.

"I can go to the theatre, and get a bully dinner, besides," he reflected, complacently.

The car rapidly proceeded uptown, passing Union Square and the Everett House at the corner of Seventeenth Street. Two blocks farther, and the passenger first introduced rose from his seat.

"Next corner," he said to the conductor.

The latter pulled the strap and the car stopped.

The gentleman got out, and turned westward up Twenty-ninth Street.

Hake scrambled out also, and followed him up the street. He crossed Madison Avenue, Fifth Avenue, and did not pause till he had reached a handsome house between Seventh and Eighth avenues. Before this time he had thrown open the coat in which he had been muffled, for the weather was not inclement, appearing to feel that there was now no further need of concealment.

He ascended the steps of the house, and rang the bell.

The door was opened directly by a servant, and he entered.

Scarcely had the door closed when Hake also ascended the steps and looked at the door-plate. The name was there, but unfortunately for Hake, he had not received even an elementary education, and could not read. This was rather inconvenient, as it stood in the way of his obtaining the information he desired.

Looking about him, he saw a schoolboy of his own age passing.

"Look here," he said, "what's that name up there on that door?"

"Can't you read?"

"I left my spectacles at home," said Hake, "and I can't read without 'em."

"It's Paul Morton, then, if you want to know," said the boy, curtly.

"Paul Morton," repeated Hake to himself. "All right!"

But he was not quite sure whether he had not been deceived. So he went to the basement door, and rang.

"What's wanted?" said the servant, curtly.

"Does Paul Morton live here?" asked Hake.

"You might say Mr. Paul Morton while you're about it," said the servant. "Yes, he lives here, and what do you want with him?"

"I was sent here," said Hake with no particular regard for truth, "by a man as said Mr. Morton was a good man, and would give me some clothes."

"Then you won't get them here," said the girl, and the door was slammed in the boy's face.

"I've found out his name now," said Hake, "sure," and he repeated it over to himself until he was certain he could remember it. He retraced his steps to Fourth Avenue, and jumped on board a returning car, and was ere long landed at the druggist's shop.

"Well," said James Cromwell, looking up, "did you do as I told you?"

"Yes," said Hake.

"What did you find out?"

"His name is Paul Morton."

"Where does he live?"

"At No. —— West Twenty-ninth Street."

"What sort of house is it?"

"A nice one."

"Are you sure you made no mistake?"

"Yes, it's all right. I want my quarter."

"Here it is."

The boy took the money and scrambled off, well content with the results of his expedition; his mind intent upon the play he was to see in the evening.

"Paul Morton!" mused the clerk, thoughtfully. "I must put that name down. The knowledge may come in use some day. I hope some time or other I shall not be starving on ten dollars a week. It may be that my rise in the world will come through this same Paul Morton. Who can tell?"