"Yes, Mr. Higgins. That was why I finally succumbed to sending for the best detectives that this country has to offer. My nursing and medical staffs are beginning to suspect themselves ... and each other...."
"All four patients were nursed and attended by the same staff members?"
"Then I suggest, in fact, request, sir," Mr. Higgins intervened, "that you do not tell us who your suspects are. It will cloud our work. An open mind and a lack of tradition.... Oh, no. Doctor, ... we are completely aware of that and will guard it, sir, with our lives.... I am referring to personal tradition with reference to staff members....
"A lack of belief in the honesty of any man we contact because he is famous, or brilliant, or noted, will be one of the most invaluable things we can have.
"Now to return to the murders. What do the autopsy findings show, exactly?"
"That they were committed with the same drug. Coniine, the active principal of hemlock. Administered hypodermically and in the first case which took effect in a little over an hour and in the second case within less than forty minutes. The second dose, that given the nurse was much larger. Our chief pharmacist has checked the supply sources. We have never had any coniine in the hospital, and it can be secured from only three houses in the country. None of them reports recent sales. We have wired all three.
"Who, qualified to administer a hypodermic, had access to the patients?" Mr. Higgins' voice was low and sudden.
"The entire nursing and medical staff practicing upon that floor."
Mr. Smooty sat blankly by. Miss Parkins took her second cigarette from her mouth and asked:
"Are the hypodermics compounded in the pharmacy?"
"No. On the floor. By the nurse on duty, acting only upon prescription from the attending physician. The medicine closets on the ward ... and every floor of that building ... have been searched after each murder. They reveal nothing."
"At night, Miss Parkins. After midnight rounds made by the student nurse. Perhaps I had better give you a full picture. The ward contains thirty beds, in four rows, each seven being separated by a glass partition. The two extra beds are in rooms for dying patients. Each ward has a day white (graduate) nurse, and four student nurses on duty. Their duty changes as to hours are not important to this case.