I observed languidly that they were most of them portraits of ladies--fair idols, no doubt, of the Major's facile adoration--and I cared to notice no more.

_My_ business in that room (I was certain of it now!) began and ended with the book-case.

I left my seat to fetch the library ladder, determining to begin the work of investigation on the top shelves.
On my way to the ladder I passed one of the tables, and saw the keys lying on it which Major Fitz-David had left at my disposal.
The smaller of the two keys instantly reminded me of the cupboards under the bookcase.

I had strangely overlooked these.

A vague distrust of the locked doors a vague doubt of what they might be hiding from me, stole into my mind.