How does Sarah Waters use imagery in Affinity?

Examples of Visual Imagery:

"The cells, however, remain so chill that the walls are wet with condensation, the lime upon them turned to a kind of bubbling curd, that marks the women's skirts with streaks of white." pg. 157

"They were not whitewashed, like the walls above, but rough, unfinished, and quite glistening with damp. Each was densely hung with iron—with rings and chains and fetters, and with other, nameless, complicated instruments whose purposes I could only, shuddering, guess at." pg. 179