Color mixing can be achieved by joining the X-Y coordinates of both colors with a line. Every point on that line represents a possible mix, with its proximity to either color representing that color's portion of the mix,-as a percentage of this line's length.

Once a point on this joining line has been selected, its chromacity is immediately obvious, it is the color beneath the point. Another line drawn from the diagram's White Point through this point to the Chromacity Curve, not only represents the Mix's chromacity, but also its luminosity. The Saturation Point of the mix's color will cross the Chromacity Curve at the Wavelength of the mixture color.

It may be pointed out that every color can be seen as the possible mix of a multitude of color pairs. This makes this method far superior to any other method I know of.

It also explains the workings of Dr. Land's Two Color Experiment that allows us to get a full color image from a pair of Black and White negatives of the same scene shot through two different color filters.  When these negatives are projected onto the same screen with a pair of projectors, through another pair of color filters so that they are superimposed,- The full color scene is reproduced.

The procedure works because the B&W film is capable of recording the Luminosity of all the colors in the scene, and a color's Luminosity will alway coincide with its Chromacity. The system provides two Wavelengths for every color. Recombining the two sets of luminosities through both color filters which are now mixed for the first time,- reproduces the missing original wavelengths and restores the original chromacities of the original scene.