After he had dropped it in and had closed the bag, he asked me where I had left Madame Fosco. I told him, and he went out at the hall door immediately to join his wife. His manner when he spoke to me was so unusually quiet and subdued that I turned and looked after him, wondering if he were ill or out of spirits.

Why my next proceeding was to go straight up to the postbag and take out my own letter and look at it again, with a vague distrust on me, and why the looking at it for the second time instantly suggested the idea to my mind of sealing the envelope for its greater security⁠—are mysteries which are either too deep or too shallow for me to fathom. Women, as everybody knows, constantly act on impulses which they cannot explain even to themselves, and I can only suppose that one of those impulses was the hidden cause of my unaccountable conduct on this occasion.