Miss Miggs, having undone her mistress, as she phrased it (which means, assisted to undress her), and having seen her comfortably to bed in the back room on the first floor, withdrew to her own apartment, in the
attic story. Notwithstanding her declaration in the locksmith's presence, she was in no mood for sleep; so, putting her light upon the table and withdrawing the little window curtain, she gazed out pensively at the wild night sky.
The English borrowed the word as attic and extended its meaning, originally in the phrases
attic story and attic floor, to designate the top story of any building just under the roof.