"I suppose," said Roland, "you thought for a moment I was trying to commit suicide. I think, Mr. Stratton, you will have a better opinion of me by-and-by. I shouldn't be at all surprised if you imagined I induced you to come in here to get you into a trap."

"You are perfectly correct," said Stratton; "and I may say, although that was my belief, I was not in the least afraid of you, for I had you covered all the time."

"Well," remarked Roland, carelessly, "I don't want to interfere with your business at all, but I wish you wouldn't cover me quite so much; that revolver of yours might go off."

"Do you mean to say," said Stratton, "that there is nothing but quinine in those capsules?"

"I'll tell you in a moment," as he opened them one by one. "No, there is nothing but quinine here. Thirty grains put up in five-grain capsules."

George Stratton's eyes began to open. Then he slowly rose, and looked with horrified face at the doctor.

"My God!" he cried; "who got the thirty grains of morphia?"

"What do you mean?" asked the doctor.

"Mean? Why, don't you see it? It is a chemist's mistake. Thirty grains of quinine have been sent you. Thirty grains of morphia have been sent to somebody else. Was it to William Brenton?"

"By Jove!" said the doctor, "there's something in that. Say, let us go to the drug store."

The two went out together, and walked to the drug store on the corner of Blank Street and Nemo Avenue.

"Do you know this writing?" said Doctor Roland to the druggist, pointing to the label on the box.

"Yes," answered the druggist; "that was written by one of my assistants."

"Can we see him for a few moments?"

"I don't know where he is to be found. He is a worthless fellow, and has gone to the devil this last few weeks with a rapidity that is something startling."

"When did he leave?"

"Well, he got drunk and stayed drunk during the holidays, and I had to discharge him. He was a very valuable man when he was sober; but he began to be so erratic in his habits that I was afraid he would make a ghastly mistake some time, so I discharged him before it was too late."

"Are you sure you discharged him before it was too late?"

The druggist looked at the doctor, whom he knew well, and said, "I never heard of any mistake, if he did make it."

"You keep a book, of course, of all the prescriptions sent out?"

"Certainly."

"May we look at that book?"

"I shall be very glad to show it to you. What month or week?"

"I want to see what time you sent this box of morphia to me."

"You don't know about what time it was, do you?

"Yes; it must have been about two weeks before Christmas."

The chemist looked over the pages of the book, and finally said, "Here it is."

"Will you let me look at that page?"

"Certainly."

The doctor ran his finger down the column, and came to an entry written in the same hand.

"Look here," he said to Stratton, "thirty grains of quinine sent to William Brenton, and next to it thirty grains of morphia sent to Stephen Roland. I see how it was. Those prescriptions were mixed up. My package went to poor Brenton."

The druggist turned pale.

"I hope," he said, "nothing public will come of this."

"My dear sir," said Roland, "something public will have to come of it. You will oblige me by ringing up the central police station, as this book must be given in charge of the authorities."

"Look here," put in Stratton, his newspaper instinct coming uppermost, "I want to get this thing exclusively for the Argus."

"Oh, I guess there will be no trouble about that. Nothing will be made public until to-morrow, and you can telegraph to-night if we find the box of capsules in Brenton's residence. We must take an officer with us for that purpose, but you can caution or bribe him to keep quiet until to-morrow."

When the three went to William Brenton's residence they began a search of the room in which Brenton had died, but nothing was found. In the closet of the room hung the clothes of Brenton, and going through them Stratton found in the vest pocket of one of the suits a small box containing what was described as five-grain capsules of sulphate of quinine. The doctor tore one of these capsules apart, so as to see what was in it. Without a moment's hesitation he said—

"There you are! That is the morphia. There were six capsules in this box, and one of them is missing. William Brenton poisoned himself! Feeling ill, he doubtless took what he thought was a dose of quinine. Many men indulge in what we call the quinine habit. It is getting to be a mild form of tippling. Brenton committed unconscious suicide!"