ON THE RELATION OF OPTICS TO PAINTING. 127 



We have not far to ""seek for the delight in light 

 and in colours, and for the dread of darkness; this 

 coincides with the endeavour to see and to recognise 

 surrounding objects. Darkness owes the greater part 

 of the terror which it inspires to the fright of what 

 is unknown and cannot be recognised. A coloured 

 picture gives a far more accurate, richer, and easier 

 conception than a similarly executed drawing, which 

 only retains the contrasts of light and shade. A 

 picture retains the latter, but has in addition the 

 material for discrimination which colours afford; by 

 which surfaces which appear equally bright in the 

 drawing, owing to their different colour, are now 

 assigned to various objects, or again as alike in colour 

 are seen to be parts of the same, or of similar objects. 

 In utilising the relations thus naturally given, the 

 artist, by means of prominent colours, can direct and 

 enchain the attention of the observer upon the chief 

 objects of the picture; and by the variety of the 

 garments he can discriminate the figures from each 

 other, but complete each individual one in itself. 

 Even the natural pleasure in pure, strongly saturated 

 colours, finds its justification in this direction. The 

 case is analogous to that in music, with the full, pure, 

 well-sounding tones of a beautiful voice. Such a one 

 is more expressive ; that is, even the smallest change 

 of its pitch, or its quality any slight interruption, 



