Abstract
The effect of color mixing on the retinal color processes was studied. In the first place, the excitability curves for two monochromatic lights were determined separately, and then the summation curve for the mixture of the two colored lights. From these experiments it was found that the law of additive summation which holds for the usual color mixing experiments does not apply to the physiological effects caused by lights in the retina. The summation curves were found a little higher than the envelope of the single curves obtained in the separate application of the colors, but the shape of the curve was very similar to that of the envelope.
Binocular mixing of colors had no influence' upon the excitability curve; From the eye illuminated by red light was obtained an excitability curve which could not be distinguished from the excitability curve for red light, by whatever color the other eye might be illuminated simultaneously.
