She must wait.

The mischief--if there had been mischief--was done; the breaking in of the bricked closet was, from the appearance of the ruins, a bygone act.

Could it have been some youthful escapade of Uncle Sylvester's, the scene of which he was revisiting as criminals are compelled to do?
And had there been anything taken from the closet--or was its destruction a part of the changes in the old house?
How could she find out without asking Kitty?
There was one way.
She remembered that Mr.Gunn had once shown a great deal of interest to Kitty about the old homestead, and even of old Mr.Lane's woodland cabin.

She would ask HIM.

It was a friendly act, for Kitty had not of late been very kind to him.
The opportunity presented itself at dusk, as Mr.Gunn, somewhat abstracted, stood apart at the drawing-room window.