had attracted HIS attention; but what BUSINESS was it of his?

She reflected that she had seen in the wall of the conservatory an old
closed staircase, now used as shelves for dried herbs and seeds, which
she had been told was the old-time communication between the garden
and Grandfather Lane's study,--the room now occupied by the stranger.
Perhaps it led still farther, and thus accounted for the space.
Determined to satisfy herself, she noiselessly descended to the
conservatory. There, surely, was the staircase,--a narrow flight of
wooden steps encumbered with packages of herbs,--losing itself in upper
darkness. By the aid of a candle she managed to grope and pick her way
up step by step. Then she paused. The staircase had abruptly ended on
the level of the study, now cut off from it by the new partition. She
was in a stifling inclosure, formed by the walls, scarcely eighteen
inches wide. It was made narrower by a singular excrescence on the old
wall, which seemed to have been a bricked closet, now half destroyed
and in ruins. She turned to descend, when a strange sound from Uncle
Sylvester's room struck her ear. It was the sound of tapping on the
floor close to the partition, within a foot of where she was standing.
At the same moment there was a decided movement of the plank of the
flooring beneath the partition: it began to slide slowly, and then was
gradually withdrawn into the room. With prompt presence of mind, she
instantly extinguished her candle and drew herself breathlessly against
the partition.

When the plank was entirely withdrawn, a ray of light slipped through
the opening, revealing the bare rafters of the floor, and a hand and arm
inserted under the partition, groping as if towards the bricked closet.
As the fingers of the exploring hand were widely extended, Marie had no
difficulty in recognizing on one of them a peculiar signet ring which