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 instead of to the carbon arc (as given), using Watson’s data for the energy distribution of the latter and Abbot’s data on that of the former (vide infra), The corresponding luminosity and percentage color excitation values were then combined as products to yield excitation values referred to sunlight, rendering them

Spectral Colors in Terms of Elementary Excitations

These values are for an equal energy spectrum. The relative magnitudes of the three elementary excitations have been chosen so that the curves for average noon sunlight have equal areas; that is, if the percentage values are plotted on a trilinear diagram, sunlight falls in the center. The absolute excitation values are based upon a convenient arbitrary unit. The percentage values are given for the red and violet only since those for the green can be found by subtracting the sum of the other two values from 100 in each case.

comparable in this respect with the values given by König and Dieterici. The respective trilinear representations of both sets of values then coincided, except for the positions of the elementary “green” excitations and the sides of the two triangles joining the green and the “violet” elementaries. Although the relation between the two green elementaries could not be determined directly, it