Charming 19th century German/Continental reverse painted glass Woman in fancy attire, titled La Jeune Parisienne

12 by 9 inches in original frame

From Wikipedia, "Reverse painting on glass is an art form consisting of applying paint to a piece of glass and then viewing the image by turning the glass over and looking through the glass at the image. Another term used to refer to the art of cold painting and gilding on the back of glass is verre églomisé, named after the French decorator Jean-Baptiste Glomy (1711–86), who framed prints using glass that had been reverse-painted. In German it is known as Hinterglasmalerei.

This art form has been around for many years. It was widely used for sacral paintings since the Middle Ages. The most famous was the art of icons in the Byzantine Empire. Later the painting on glass spread to Italy, where in Venice it influenced its Renaissance art. Since the middle of the 18th century, painting on glass became favored by the Church and the nobility throughout Central Europe. A number of clock faces were created using this technique in the early-to-mid-19th century. Throughout the 19th century painting on glass was widely popular as folk art in Austria, Bavaria, Moravia, Bohemia and Slovakia.