56 GOETHE'S ' FARBENLEHRE.' 



washed away a coating capable of converting a blue 

 like that before him into the black of the original 

 painting.' 



Goethe inspected the picture, saw the phenomenon, 

 and explained it. To deepen the hue of the velvet coat 

 the painter had covered it with a special varnish, which, 

 by absorbing part of the water passed over it, was con- 

 verted into a turbid medium, through which the black 

 behind instantly appeared as blue. To the great joy 

 of the painter, he found that a few hours' continuance 

 in a dry place restored the primitive black. By the 

 evaporation of the moisture the optical continuity of 

 the varnish (to which essential point Goethe doe3 not 

 refer) was re-established, after which it ceased to act as 

 a turbid medium. 



This question of turbid media took entire possession 

 of the poet's mind. It was ever present to his observa- 

 tion. It was illustrated by the azure of noonday, and 

 by the daffodil and crimson of the evening sky. The 

 inimitable lines written at Ilmenau — 



Ueber alien Gipf eln 



1st Rub.', 



In alien Wipfeln 



Spiirest Du 



Kaum einen Haucb— 



suggest a stillness of the atmosphere which would allow 

 the columns of fine smoke from the foresters' cottages 

 to rise high into the air. He would thus have an 

 opportunity of seeing the upper portion of the column 

 projected against bright clouds, and the lower portion 

 against dark pines, the brownish yellow of the one, and 

 the blue of the other, being strikingly and at once 

 revealed. He was able to produce artificially at will 

 the colours which he had previously observed in nature. 



