Imago 1

What we call transparent is not a peculiarity of the air or water or any other body described as such, but a joint force that is inherent in bodies and all other materials. The nature of light is presented in transparency, when the latter has no fixed limit. But it is obvious that transparency needs to have a threshold and from what happens it seems that the threshold is the color. The color itself may be the threshold when it is juxtaposed to light.