Hello, My aim is to build a small reflecting sundial as designed by Sir Isaac Newton. I found from a website that it consists of a ceiling and a small mirror. What I want to know is how it works, the concepts behind it and how to build one. It's for an undergraduate project that I've got. What I've learned is that it depends on the latitude, longitude and orientation of the building. Resource : http://interiorsundials.tripod.com Can anybody help me ?