"The Window at the White Cat" (1910) is a detective novel by Mary Roberts Rinehart.
Excerpt from the book: "In my criminal work anything that wears skirts is a lady, until the law proves her otherwise. From the frayed and slovenly petticoats of the woman who owns a poultry stand in the market and who has grown wealthy by selling chickens at twelve ounces to the pound, or the silk sweep of Mamie Tracy, whose diamonds have been stolen down on the avenue - all the wearers are ladies, and as such announced by Hawes. In fact, he carries it to excess. He speaks of his wash lady, with a husband who is an ash merchant. So when Hawes announced a lady, I took my feet off my desk, put down the brief I had been reading, and rose perfunctorily. With my first glance at my visitor, however, I threw away my cigar, and I have heard since, settled my tie. That this client was different was borne in on me at once by the way she entered the room."