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 is 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.  I never felt in my life so strongly the truth of Hamlet’s words: