To the scales of chromatic power I add another series of scales, in which yellow, being the first tonic, and blue the second, the numerical divisions express the ratios which the colours in each scale bear to one another in respect to light and shade. Thus red is to yellow, in respect to light, as 2:3; blue to red, as 3:4; green to orange, as 5:6, and purple to green, as 6:7. These scales may therefore be termed scales for the colour-blind, because, in comparing colours, those whose sight is thus defective, naturally compare the ratios of the light and shade of which different colours are primarily constituted. [Illustration] The following is a series of five complete scales of the harmonic parts into which the light and shade in colours may be divided in each scale according to the above arrangement:— _Second Series of Scales._ ----+-------+-------+-------+-------+------+-------+-------+-------+------ |Tonic. | | | | | | | | | |Supertonic. | | | | | | | | |Mediant. | | | | | | | | |Subdominant. | | | | | | | | |Dominant. | | | | | | | | |Submediant. | | | | | | | | |Subtonic. | | | | | | | | |Semi-subtonic. | | | | | | | | |Tonic. ----+-------+-------+-------+-------+------+-------+-------+-------+------ I. |(¹⁄₂) |(⁴⁄₉) |(²⁄₅) |(³⁄₈) |(¹⁄₃) |(³⁄₁₀) |(²⁄₇) |(⁴⁄₁₅) |(¹⁄₄) |Yellow.|Yellow-|Orange.|Red- |Red. |Red- |Purple.|Blue- |Blue. | |orange.| |orange.| |purple.| |purple.| ----+-------+-------+-------+-------+------+-------+-------+-------+------ II. |(¹⁄₄) |(²⁄₉) |(¹⁄₅) |(³⁄₁₆) |(¹⁄₆) |(³⁄₂₀) |(¹⁄₇) |(²⁄₁₅) |(¹⁄₈) |Purple.|Blue- |Blue |Blue- |Green.|Yellow-|Yellow |Yellow-|Orange | |purple |hue. |green | |green |hue. |orange | | |hue. | |hue. | |hue. | |hue. | ----+-------+-------+-------+-------+------+-------+-------+-------+------ III.|(¹⁄₈) |(¹⁄₉) |(¹⁄₁₀) |(³⁄₃₂) |(¹⁄₁₂)|(³⁄₄₀) |(¹⁄₁₄) |(¹⁄₁₅) |(¹⁄₁₆) |Yellow |Yellow-|Orange |Red- |Red |Red- |Purple |Blue- |Blue |hue. |orange |hue. |orange |hue. |purple |hue. |purple |hue. | |hue. | |hue. | |hue. | |hue. | ----+-------+-------+-------+-------+------+-------+-------+-------+------ IV. |(¹⁄₁₆) |(¹⁄₁₈) |(¹⁄₂₀) |(³⁄₆₄) |(¹⁄₂₄)|(³⁄₈₀) |(¹⁄₂₈) |(¹⁄₃₀) |(¹⁄₃₂) |Purple |Blue- |Blue- |Blue- |Green |Yellow-|Yellow-|Yellow-|Orange |hue. |purple-|toned |green- |hue. |green- |toned |orange-|hue. | |toned |gray. |toned | |toned |gray. |toned | | |gray.