I felt pretty confident.

But the wise man always holds a doubt in reserve.

And, in the present case, having regard to the obviously serious condition of the patient, such a doubt was eminently disturbing.

Indeed, as I pocketed my stethoscope and took a last look at the motionless, silent figure, I realized that my position was one of extraordinary difficulty and perplexity.

On the one hand my suspicions--aroused, naturally enough, by the very unusual circumstances that surrounded my visit--inclined me to extreme reticence; while, on the other, it was evidently my duty to give any information that might prove serviceable to the patient.
As I turned away from the bed Mr.Weiss stopped his slow pacing to and fro and faced me.