"Yes, I see that. But what is your own opinion of the case?"

"Well," he said, "let us consider the facts in order. Here is a man who,
we assume, is under the influence of a poisonous dose of morphine. The
question is, did he take that dose himself or was it administered to him
by some other person? If he took it himself, with what object did he
take it? The history that was given to you seems completely to exclude
the idea of suicide. But the patient's condition seems equally to
exclude the idea of morphinomania. Your opium-eater does not reduce
himself to a state of coma. He usually keeps well within the limits of
the tolerance that has been established. The conclusion that emerges is,
I think, that the drug was administered by some other person; and the
most likely person seems to be Mr. Weiss."

"Isn't morphine a very unusual poison?"

"Very; and most inconvenient except in a single, fatal dose, by reason
of the rapidity with which tolerance of the drug is established. But we
must not forget that slow morphine poisoning might be eminently
suitable in certain cases. The manner in which it enfeebles the will,
confuses the judgment and debilitates the body might make it very useful
to a poisoner whose aim was to get some instrument or document executed,
such as a will, deed or assignment. And death could be produced
afterwards by other means. You see the important bearing of this?"

"You mean in respect of a death certificate?"

"Yes. Suppose Mr. Weiss to have given a large dose of morphine. He then
sends for you and throws out a suggestion of sleeping sickness. If you
accept the suggestion he is pretty safe. He can repeat the process until