Torgerson's multidimensional triad ratio scaling procedure was utilized to determine similarity scale values for all pairs of ten color chips for each of nine normal and four color deficient subjects. These scale values were arrayed as a matrix with rows for scale values and columns for subjects. The matrix of cross-products between subjects was factored, yielding a clear three-dimensional simple structure with all the normal subjects lying in the plane, and all the color deficient subjects lying in a second. Factor scores associated with various directions in this space were then determined and analyzed as multi-dimensional scales.