This book serves to update knowledge about light with the help of new actual data derived from the easily reproducible experiments described therein. They form the basis of a new theory that interprets up-to-date verifiable information according to the various speeds of the lights involved.

In view of recent rapid advances in technology, one may be surprised to learn that at least two of the basic tenets of optics are over a thousand years old, namely the law of reflection, over two millennia old, and the law of reciprocity, which has not changed for over a thousand years. The aim of this treatise is to update our knowledge about light with the help of new actual data derived from easily reproducible experiments.

Since light is in space and requires time for its motion, these terms are defined as the basis of actual new observations. Similarly, the second chapter furnishes a brief historical background. The chapter Light Speed in Media reports relevant new and old experiments with up-to-date interpretations while Speeds in Space examines anew light’s general motions in space.