552 GARDEN MANAGEMENT. 



colours ; and upon it depend the brilliance and force of every conception. 

 From the combination of these secondaries arise the three tertiary colours,— 

 olive from the mixture of purple and green ; citron from the mixture of 

 green and orange ; and russet from the mixture of orange and purple. These 

 tertiaries, however, stand in the same relation to the secondaries as the 

 secondaries do to the primaries,— olive to orange, citron to puri^le, and russet 

 to green. 



1724. Dr. Lindley, in commenting on Mr. Chevreul's work on colour, 

 remarks : " As to contrast of colour, it is found by experiment, and it may 

 also be proved by cl 2^^"^^^^'^ reasoning, that whenever the eye regards 

 two or more different colours at one and the same time, the colour of each 

 is so modified, that it appears, by the contrast, to be of that colour which 

 would be produced by the addition of itself to the complementary colours 

 of its neighbours ; and this modification is greatest where the contrast is 

 strongest, and least where that is the weakest." When colours that are 

 as nearly as possible complementary to each other are contrasted," the 

 colour of each is rendered more intense, or its tone is deepened. This fol- 

 lows immediately from the general principle laid down, and is fully confirmed 

 by experiment. Colours, when contrasted with white, are deepened in tone, 

 and at the same time appear more brilliant ; the white itself beiog tinged 

 slightly with the complementary of the contrasted colour. Contrasted with 

 black, colours appear of a higher tone, or less intense ; and the black is 

 feebly tinged with the complementary of the contrasted colour : grey, being 

 intermediate between black and white, produces an intermediate effect on 

 colours with which it is contrasted. This is seen in the following results, 

 obtained by placing different colours in contact with a grey ground : — 



Hed and Grey. — The grey appears greenish, in consequence of its receiving 

 the complementary of the red ; the red appears purer, — less orange- 

 colour, perhaps. 



Orange and Grey. — The grey appears bluish ; the orange purer, more bril- 

 liant, and, perhaps, a little yellower. 



Yellow and Grey. — The grey is tinged violet ; the yellow appears more 

 brilliant, and at the same time less green. 



Green and Grey. — The grey is reddish, and the green is more brilliant, 

 perhaps yellower. 



Bh(-e and Grey. — The grey is tinged with orange ; the blue appears more 

 brilliant, and a little greenish. 



Indigo and Grey. — As the last. 



Violet and Grey. — The grey becomes yellowish ; the violet purer, aod lea 

 dull. 



1725. "When two compound colours, having one and the same simple colour 

 common to them both, are contrasted, the common colour loses its effect in 

 a greater or less degree. For exaraj^le, take orange (composed of yellow and 

 red) and green (composed of yellow and blue) ; their common colour (yellow) 



