110 p. C. on the Colours t/iat entei' into the [Aug. 



If we try the law by the same method in Fraunhofer's 

 spectrum, we require the whole of the blue and four of the 

 indigo, before we arrive at the accidental colour of the 

 central red. 



If we now refer to the article on accidental colours, we 

 shall see that the accidental colour of red is stated to be 

 bluish green. 



By the same law we shall find that the accidental colour 

 of a great part of the green in both spectra, is in the violet, 

 and a large portion of the violet of Fraunhofer's spectrum 

 in the blue ; another portion includes the whole of the 

 green ; and the remainder the yellow and part of the orange ; 

 so that all these colours must be complementary to different 

 parts of it. 



It is obvious, therefore, that this law, though favourable 

 to the theory which requires blue to be the complement of 

 red, is so much at variance with itself, that its support is 

 of no value. 



If, however, we leave the law and turn to the facts, we 

 shall find the most ample testimony that the accidental 

 colour of red, is blue ; of green, crimson ; and of violet, 

 yellow. 



I frequently sit in a room where there is a cabinet piano, 

 the front of which is covered with crimson silk, and where 

 there is occasionally introduced a sofa covered with scarlet 

 moreen. In consequence of these opportunities, the follow- 

 ing experiments have been so often repeated, that I cannot 

 be mistaken in the result. The piano is at the end of the 

 room, and the sofa is generally so placed that I can include 

 both objects at one view. 



When I fix my eyes for about a minute, or even less, 

 upon the crimson silk, and then turn them to the white 

 ceiling of the room, the form of the silk is seen of a 

 distinct green colour, without the least approach to blue- 



If I make the experiment with the scarlet moreen, the 

 accidental colour seen on the ceiling, is an equally decided 

 blue. 



If instead of looking at the ceiling, I merely close my 

 eyes after looking at the objects, the accidental colours, 

 seen by the light which passes through the eye-lids, are the 

 same, but much more vivid ; indeed, when the experiments 



