Sentence:  "How is it, then, that the woman who came into the room about nine left to traces with her muddy boots?" / "I am glad you raise the point. It occurred to me at the time. The charwomen are in the habit of taking off their boots at the commissionaire's office, and putting on <WSD>list</WSD> slippers." 
Meaning of the word marked with <WSD> tags:  Material used for cloth selvage.