Jeffrey's repeated hints as to his intentions, and the very significant preparations that he had made, were enough to negative any idea of foul play.

And yet the woman's presence in the chambers at that time, the secret manner of her arrival and her precautions against recognition, strongly suggested some kind of complicity in the dreadful event that followed.
But what complicity is possible in the case of suicide?
The woman might have furnished him with the syringe and the poison, but it would not have been necessary for her to go to his chambers for that purpose.
Vague ideas of persuasion and hypnotic suggestion floated through my brain; but the explanations did not fit the case and the hypnotic suggestion of crime is not very convincing to the medical mind.

Then I thought of blackmail in connection with some disgraceful secret; but though this was a more hopeful suggestion, it was not very probable, considering Jeffrey's age and character.
And all these speculations failed to throw the faintest light on the main question: "Who was this woman ?" A couple of days passed, during which Thorndyke made no further reference to the case.

He was, most of the time, away from home, though how he was engaged I had no idea.

What was rather more unusual was that Polton seemed to have deserted the laboratory and taken to outdoor pursuits.