Describe Madeline temporary tomb. What does the narrator notice about Madeline's appearance and condition after looking at her corpse?

Here is a description of the tomb,

"The vault in which we placed it (and which had been so long unopened that our torches, half smothered in its oppressive atmosphere, gave us little opportunity for investigation) was small, damp, and entirely without means of admission for light; lying, at great depth, immediately beneath that portion of the building in which was my own sleeping apartment. It had been used, apparently, in remote feudal times, for the worst purposes of a donjon-keep, and, in later days, as a place of deposit for powder, or some other highly combustible substance, as a portion of its floor, and the whole interior of a long archway through which we reached it, were carefully sheathed with copper. The door, of massive iron, had been, also, similarly protected. Its immense weight caused an unusually sharp grating sound, as it moved upon its hinges."

and of Madeline,

"The disease which had thus entombed the lady in the maturity of youth, had left, as usual in all maladies of a strictly cataleptical character, the mockery of a faint blush upon the bosom and the face, and that suspiciously lingering smile upon the lip which is so terrible in death. We replaced and screwed down the lid, and, having secured the door of iron, made our way, with toil, into the scarcely less gloomy apartments of the upper portion of the house."