146 ON COLOUR. Part 1. 



Some of the former, as well as grey, are better suited for 

 grounds than for any marked position in coloured composition, 

 as I have shown in Sect. IX. p. 107. 



The proper proportions of the colours to each other are 

 indispensable. I have already shown that to be all of the 

 same quantity would be fatal to them ; and some are required 

 to be in larger, others in smaller, proportions. Thus, when a 

 blue, red, and yellow are put together, their proportions 

 should be very different ; and the same quantity of yellow as 

 of blue or red would have a disagreeable effect. But it is cer- 

 tainly difficult to determine the exact quantity of each colour. 



XVIII. In the foregoing combinations of colours I have 

 merely considered how they affect each other in juxtaposi- 

 tion, without noticing the proper quantity of each required 

 for the harmony of a composition. It must, however, be 

 borne in mind that, to give due effect to a coloured design, 

 the proper proportions of the colours to each other are indis- 

 pensable. I have already shown that, to be all of the same 

 quantity, would be fatal to it ; and some are required to be 

 in larger, others in smaller proportions. Thus, when a blue, 

 a red, and a yellow are put together, their proportions should 

 be very different ; and the same quantity of yellow as of blue 

 or red would have a disagreeable effect. It is certainly 

 difficult to determine the exact quantity of each colour with- 

 out knowing the exact number of the primary, secondary, 

 and other colours to be introduced into a composition, or 

 without considering the several conditions to which it might 

 be subject ; but it may be laid down, as a general rule, that 

 as the greatest quantity required in the three primaries is 

 blue, then red, and then yellow, so too the proper ratio 

 should be maintained in the combinations of the secondary *, 

 as well as mixed, hues. In all cases where green is used, it 



* See pp. 10, 22, 61, 76, 77, 94. 



