How can you tell if the "mirror" in the room you are in, restroom, motel, etc is really a mirror or a 2-WAY GLASS??? These tips were given by a police woman who travels across the nation giving seminars and safety techniques for women. Personally, I think that men need to be aware of this also.
1. Place the tip of your fingernail against the reflective surface. If there IS a gap between your fingernail and the image of the nail, you can rest assured that you are touching a REAL mirror. No one is watching you from the other side.
2. If your fingernail DIRECTLY TOUCHES the image of your fingernail, then BEWARE! It is a two-way mirror and someone might be watching YOU.