I have a great collection of historic and vintage design, decorating and sewing books. A good friend helped me learn how to use the internet as an excellent source for even more information from days gone by. I find the descriptions, advice and illustrations fascinating.
In the ad below you will see the term "window treatments" used. I always assumed that this was a more contemporary description for draperies and curtains but the ad, from 1903 proves that the term is much older than I thought. I also found the term "window furnishings" used in a book from 1919 titled The Practical Book of Interior Decoration in the chapter titled "Windows and Their Treatment".
Another interesting tidbit was found in the 1910 book titled House Furnishing Advertising by William Bordsodi where bed comforters are referred to as "comforts" and "comfortables". I have never seen this charming term before. Here is a quote from the book. "When the thermometer begins to hover around the zero mark then comfortables are the order of the day, or the night rather.