I have 2 old (circa 1800?) black and white photos sizes 9x11 inches in glass. It's a picture of a little girl in a flower field and another of a woman outside the home, sitting on a chair with her little girl standing in front, and she is feeding a cat. It is framed, and I set it against our glass window overlooking the lake so that it receives good lighting. It has been there for over 20 years. If it is not against a light, you can not see the picture properly. It is like a glass negative, only it comes out positive against the light. You can see the picture both ways. What kind of photo do I have? Is this an ambrotype photo?
I wish I could post photos but I don't know how to do so.