There was evidently a mystery
somewhere; and if no solution to it could be found, the doubt would be
cast on someone. In such cases the guesses of the majority are bound
to follow the line of least resistance; and if it could be proved that
any personal gain to anyone could follow Mr. Trelawny’s death, should
such ensue, it might prove a difficult task for anyone to prove
innocence in the face of suspicious facts. I found myself
instinctively taking that deferential course which, until the plan of
battle of the prosecution is unfolded, is so safe an attitude for the
defence. It would never do for me, at this stage, to combat any
theories which a detective might form. I could best help Miss Trelawny
by listening and understanding. When the time should come for the
dissipation and obliteration of the theories, I should be quite willing
to use all my militant ardour, and all the weapons at my command. “You will of course do your duty, I know,” I said, “and without fear. What course do you intend to take?”

“I don’t know as yet, sir. You see, up to now it isn’t with me even a
suspicion. If any one else told me that that sweet young lady had a
hand in such a matter, I would think him a fool; but I am bound to
follow my own conclusions. I know well that just as unlikely persons
have been proved guilty, when a whole court—all except the prosecution
who knew the facts, and the judge who had taught his mind to
wait—would have sworn to innocence. I wouldn’t, for all the world,
wrong such a young lady; more especial when she has such a cruel weight
to bear. And you will be sure that I won’t say a word that’ll prompt
anyone else to make such a charge. That’s why I speak to you in
confidence, man to man. You are skilled in proofs; that is your
profession. Mine only gets so far as suspicions, and what we call our
own proofs—which are nothing but ex parte evidence after all. You
know Miss Trelawny better than I do; and though I watch round the
sick-room, and go where I like about the house and in and out of it, I
haven’t the same opportunities as you have of knowing the lady and what
her life is, or her means are; or of anything else which might give me
a clue to her actions. If I were to try to find out from her, it would
at once arouse her suspicions. Then, if she were guilty, all
possibility of ultimate proof would go; for she would easily find a way
to baffle discovery. But if she be innocent, as I hope she is, it
would be doing a cruel wrong to accuse her. I have thought the matter
over according to my lights before I spoke to you; and if I have taken
a liberty, sir, I am truly sorry.”

“No liberty in the world, Daw,” I said warmly, for the man’s courage
and honesty and consideration compelled respect. “I am glad you have
spoken to me so frankly. We both want to find out the truth; and there
is so much about this case that is strange—so strange as to go beyond
all experiences—that to aim at truth is our only chance of making
anything clear in the long-run—no matter what our views are, or what
object we wish to achieve ultimately!”  The Sergeant looked pleased as
he went on:

“I thought, therefore, that if you had it once in your mind that
somebody else held to such a possibility, you would by degrees get
proof; or at any rate such ideas as would convince yourself, either for
or against it. Then we would come to some conclusion; or at any rate
we should so exhaust all other possibilities that the most likely one
would remain as the nearest thing to proof, or strong suspicion, that
we could get. After that we should have to—”

Just at this moment the door opened and Miss Trelawny entered the room. The moment she saw us she drew back quickly, saying:

“Oh, I beg pardon! I did not know you were here, and engaged.”  By the
time I had stood up, she was about to go back. “Do come in,” I said; “Sergeant Daw and I were only talking matters
over.”

Whilst she was hesitating, Mrs. Grant appeared, saying as she entered
the room: “Doctor Winchester is come, miss, and is asking for you.”

I obeyed Miss Trelawny’s look; together we left the room. When the Doctor had made his examination, he told us that there was
seemingly no change. He added that nevertheless he would like to stay
in the house that night if he might. Miss Trelawny looked glad, and
sent word to Mrs. Grant to get a room ready for him. Later in the day,
when he and I happened to be alone together, he said suddenly:

“I have arranged to stay here tonight because I want to have a talk
with you. And as I wish it to be quite private, I thought the least
suspicious way would be to have a cigar together late in the evening
when Miss Trelawny is watching her father.”  We still kept to our
arrangement that either the sick man’s daughter or I should be on watch
all night. We were to share the duty at the early hours of the
morning. I was anxious about this, for I knew from our conversation
that the Detective would watch in secret himself, and would be
particularly alert about that time. The day passed uneventfully. Miss Trelawny slept in the afternoon; and
after dinner went to relieve the Nurse. Mrs. Grant remained with her,
Sergeant Daw being on duty in the corridor. Doctor Winchester and I
took our coffee in the library. When we had lit our cigars he said
quietly:

“Now that we are alone I want to have a confidential talk. We are
‘tiled,’ of course; for the present at all events?”

“Quite so!” I said, my heart sinking as I thought of my conversation
with Sergeant Daw in the morning, and of the disturbing and harrowing
fears which it had left in my mind. He went on:

“This case is enough to try the sanity of all of us concerned in it. The more I think of it, the madder I seem to get; and the two lines,
each continually strengthened, seem to pull harder in opposite
directions.”

“What two lines?”  He looked at me keenly for a moment before replying. Doctor Winchester’s look at such moments was apt to be disconcerting. It would have been so to me had I had a personal part, other than my
interest in Miss Trelawny, in the matter. As it was, however, I stood
it unruffled. I was now an attorney in the case; an amicus curiae in
one sense, in another retained for the defence. The mere thought that
in this clever man’s mind were two lines, equally strong and opposite,
was in itself so consoling as to neutralise my anxiety as to a new
attack. As he began to speak, the Doctor’s face wore an inscrutable
smile; this, however, gave place to a stern gravity as he proceeded:

“Two lines:  Fact and—Fancy! In the first there is this whole thing;
attacks, attempts at robbery and murder; stupefyings; organised
catalepsy which points to either criminal hypnotism and thought
suggestion, or some simple form of poisoning unclassified yet in our
toxicology. In the other there is some influence at work which is not
classified in any book that I know—outside the pages of romance.