It is clear that Aylmer has invested a lot of time and energy into converting his laboratory into rooms where his beautiful wife will feel at home and comforted. It is obvious that the rather dingy and gothic laboratory of his youth where he achieved such scientific exploits would not have been a suitable location for his wife to be, and so the text describes the beauty of the rooms that Aylmer has converted:
Aylmer had converted those smoky, dingy, sombre rooms, where he had spent his brightest years in recondite pursuits, into a series of beautiful apartments not unfit to be the secluded abode of a lovely woman. The walls were hung with gorgeous curtains, which imparted the combination of grandeur and grace that no other species of adornment can achieve; and as they fell from the ceiling to the floor, their rich and ponderous folds, concealing all angles and straight lines, appeared to shut in the scene from infinite space.
Note the emphasis on the positive adjectives such as "gorgeous," "rich and ponderous," and the way that the curtains removed all "angles and straight lines" from the rooms. Initially, this transformation seems to be rather a surprise to the reader, as there are certain expectations that are created in our minds about what Aylmer's laborotory will look like. Yet it ties in with the theme of appearances vs. reality which dominates this short story. The laborotory has the appearance of being a place of beauty and a sophisticated place, whereas the reality is that it is a butcher's shop that will take the life of the poor innocent Georgiana. In the same way, Aylmer tries to give the appearance of being a kind, loving and considerate husband, whereas the truth is much more sinister and disturbing.