136 ON THE EELATION OF OPTICS TO PAINTING. 



translate her; yet this translation may give us an 

 impression in the highest degree distinct and forcible, 

 not merely of the objects themselves, but even of the 

 greatly altered intensities of light under which we 

 view them. The altered scale is indeed in many cases 

 advantageous, as it gets rid of everything which, in 

 the actual objects, is too dazzling, and too fatiguing 

 for the eye. Thus the imitation of Nature in the 

 picture is at the same time an ennobling of the im- 

 pression on the senses. In this respect we can often 

 give ourselves up more calmly and continuously, to the' 

 consideration of a work of art, than to that of a real 

 object. The work of art can produce those gradations 

 of light, and those tints in which the modelling of the 

 forms is most distinct and therefore most expressive. 

 It can bring forward a fulness of vivid fervent colours, 

 and by skilful contrast can retain the sensitiveness of 

 the eye in advantageous equilibrium. It can fearlessly 

 apply the entire energy of powerful sensuous impres- 

 sions, and the feeling of delight associated therewith, 

 to direct and enchain the attention ; it can use their 

 variety to heighten the direct understanding of what 

 is represented, and yet keep the eye in a condition of 

 excitation most favourable and agreeable for delicate 

 sensuous impressions. 



If, in these considerations, my having continually 

 laid much weight on the lightest, finest, and most 



