ccused. And so in one or two other cases that I have in hand; they
could be equally well conducted by someone else. The inference is that
our friend is not connected with any of these cases, but that he
believes me to possess some exclusive information concerning
him--believes me to be the one person in the world who suspects and can
convict him. Let us assume the existence of such a person--a person of
whose guilt I alone have evidence. Now this person, being unaware that I
have communicated my knowledge to a third party, would reasonably
suppose that by making away with me he had put himself in a position of
security.

"Here, then, is our first point. The sender of this offering is probably
a person concerning whom I hold certain exclusive information.

"But see, now, the interesting corollary that follows from this. I,
alone, suspect this person; therefore I have not published my
suspicions, or others would suspect him too. Why, then, does he suspect
me of suspecting him, since I have not spoken? Evidently, he too must be
in possession of exclusive information. In other words, my suspicions
are correct; for if they were not, he could not be aware of their
existence.

"The next point is the selection of this rather unusual type of cigar.
Why should he have sent a Trichinopoly instead of an ordinary Havana
such as Bartletts actually manufacture? It looks as if he were aware of
my peculiar predilection, and, by thus consulting my personal tastes,
had guarded against the chance of my giving the cigar to some other
person. We may, therefore, infer that our friend probably has some
knowledge of my habits.

"The third point is, What is the social standing of this gentle
stranger, whom we will call X? Now, Bartletts do not send their
advertisements and samples to Thomas, Richard and Henry. They send,
chiefly, to members of the professions and men of means and position. It
is true that the original package might have been annexed by a clerk,
office boy or domestic servant; but the probabilities are that X
received the package himself, and this is borne out by the fact that he
was able to obtain access to a powerful alkaloidal poison--such as this
undoubtedly is."

"In that case he would probably be a medical man or a chemist," I
suggested.

"Not necessarily," replied Thorndyke. "The laws relating to poisons are
so badly framed and administered that any well-to-do person, who has the
necessary knowledge, can obtain alm