Marguerite Waterman Cobb's nightdress appears to be silk, and features machine lace trimming, small tucks at center front and a small ribbon rose. However, the fabric is not silk. It is artificial silk.

Made from wood pulp, artificial silk, now called rayon, was the first man-made or chemically-made fiber. It was developed to imitate expensive silk. Early rayon was not pleasant against the skin, but by the late 1920s it had been improved to the point that it was ideal for lingerie. It brought attractive affordable silk-like underwear within range of everyone’s pocket book.

In the late 1920s Sear’s catalogues and others carried pages of colorful very inexpensive rayon underwear deep into Maine’s most rural areas. The development of different kinds of low priced rayon fabrics suitable for dresses and other garments contributed to the collapse of the American silk industry.