How does Florence Nightingale use imagery in Notes on Nursing?

Examples of Imagery:

"My heart always sinks within me when I hear the good housewife of every class, say, 'I assure you the bed has been well slept in,' and I can only hope that it is not true. What? is the bed already saturated with someone else's damp before my patient comes to exhale in it his own damp? Has it not had a chance to be aired? No, not one. 'It has been slept in every night.'" pg. 81

"To attempt to keep a ward warm at the expense of making the sick repeatedly breathe their own hot, humid, putrescing atmosphere is a certain way to delay recovery or to destroy life." pg. 16