The Yellow Wallpaper

In The Yellow Wallpaper, Gilman uses a pretty obvious metaphoric device to portray the emotional state of her character. In her hallucinationatory state, she perceives a woman trapped behind the wallpaper of her room. Her state is such, that the wallpaper makes her physically ill and she attempts to free this "woman". After some time, she begins to see not only one, but that there were perhaps "a great many women behind".
Gilman's message is blatant. Her main character, as a woman, is trapped in a world from which she cannot escape. She is treated essentially as a child by her husband and all those around her, and is powerless to effect her own life and do as she feels is best. She cannot free herself, and she imagines the woman trapped behind the wallpaper, and attempts to extricate her. Instead of understanding that it is her own confining life which is making her ill, in her hallucinations, she imagines that it is the wallpaper (symbolizing her life) which is making her mad.
I found that Gilman's point, while clear and effective, was somewhat too obviously stated in her story. The metaphor is too apparent, the device too simple, and left very little up to the reader to interpret.