What Is Light?

It is very difficult to say what light is. According to a discarded theory it consists of the actual distribution of particles in every direction by the heavenly luminaries. Perhaps it consists of vibrations or ether waves. But we may say something about light: a. It is movement. Light travels at the rate of 186,000 miles per second, b. It is closely related to heat. c. It is the indispensable condition for all life. In absolute darkness, which would probably also be absolute zero, no life...