Why then did I again approach the closet and withdraw the bolt?
My resolution was instantly conceived, and executed without faultering.
The door was formed of light materials.

The lock, of simple structure, easily forewent its hold.

It opened into the room, and commonly moved upon its hinges, after being unfastened, without any effort of mine.
This effort, however, was bestowed upon the present occasion.

It was my purpose to open it with quickness, but the exertion which I made was ineffectual.

It refused to open.
At another time, this circumstance would not have looked with a face of mystery.