"You need not be frightened.

I know every nook of the place." "I am not frightened," said Letty, and made no further objection.
At the top of that stair they entered a straight passage, in the middle of which was a faint glimmer of light from an oval aperture in the side of it.

Thither Tom led Letty, and told her to look through.

She did so.
Beneath lay the great gulf, wide and deep, of the hall they had just left.

This was the little window, high in its gable, through which, in far-away times, the lord or lady of the mansion could oversee at will whatever went on below.
The rain had ceased as suddenly as it came on, and already lights were moving about in the darkness of the abyss--one, and another, and another, was searching for something lost in the hurry of the scattering.