Late in the 19th century, before the rising popularity of the wrist watch, this type of watch might have been worn by a woman, carried on a long chain, and hung from a chatelaine (type of brooch), pinned to the front of the dress or jacket. These women’s watches were produced in both open faced styles and hunter (covered front) styles. Open faced watches had the winder at the 12, and hunter styles generally had the winder at the 3. Both might have been used by women. Early wrist watches usually utilized the hunter cased styles (crown at 3, but without the cover). Many of these open faced watches (crown at 3) were converted for use as wrist watches by their owners. The subject watch is an open faced model (crown at12). Converting such watches (I consider) is awkward because the lugs were added at the 9 and 3 positions, thus the orientation on the wrist is a bit awkward. Yours may very well be a conversion, but it appears to have been well done, so it is anyone’s guess as the whether it is a conversion, or perhaps made that way.
I have shown a picture of a Rolex of about the same vintage. It has the crown at the 3, and it might have been considered a conversion, but it was made this way.