Red and Yellow accord better than Red and Orange. Red and Blue ” ” Red and Violet. Yellow and Red ” ” Yellow and Orange. Yellow and Blue ” ” Yellow and Green. Blue and Red ” ” Blue and Violet. Blue and Yellow ” ” Blue and Green. 239. 3rd. _The arrangement of Red, Yellow, or Blue with a binary colour containing the former, contrasts the better, as the simple colour is essentially more luminous than the binary._ Whence it follows, that in this arrangement, it is an advantage for the red, yellow, or blue to be of lower tone than the binary colour. _Examples._ Red and Violet accord better than Blue and Violet. Yellow and Orange ” ” Red and Orange. Yellow and Green ” ” Blue and Green. 240. 4th. _When two colours accord badly together, it is always advantageous to separate them by White._ In this case it is more advantageous to place each colour next to white, than in an assortment where the two colours are together beside white. 241. 5th. _Black never produces a bad effect when it is associated with two luminous colours. It is therefore often preferable to White, especially in an assortment where it separates the colours from each other._ _Examples._ 1. Red and Orange. Black is preferable to white in the arrangements 2 and 3 of these two colours. 2. Red and Yellow. 3. Orange and Yellow. 4. Orange and Green. 5. Yellow and Green. Black, with all these binary assortments, produces harmony of contrast. 242. 6th. _Black in combination with sombre colours, such as blue and violet, and with broken tones of luminous colours, produces harmony of analogy, which, in many instances, may have a good effect._ The harmony of analogy of black, associated with blue and violet, is preferable to the harmony of contrast of the assortment white, blue, violet, white, &c., the latter being too crude. 243. 7th. _Black does not accord so well with two colours, one of which is luminous, the other sombre, as when it is associated with two luminous colours. In the first instance the combination is so much the less agreeable as the luminous colour is more brilliant._ With all the following assortments Black is inferior to White. 1. Red and Blue. 2. Red and Violet. 3. Orange and Blue. 4. Orange and Violet. 5. Yellow and Blue. 6. Green and Blue. 7. Green and Violet. With the assortment yellow and violet, if it is not inferior to white, it produces only a mediocre effect. 244. 8th. _Although Grey never produces exactly a bad effect in its association with two luminous colours, yet in most cases its assortments are dull, and it is inferior to Black and White_.