50 ox Goethe's scientific researches. 



sake of explaining the phenomena, which seem to him so 

 absurd, that he looks upon the interpretation as no inter- 

 pretation at all. Above all, the idea that white light 

 could be composed of coloured light seems to have been 

 quite inconceivable to him ; at the very beginning of the 

 controversy, he rails at the disgusting Newtonian white of 

 the natural philosophers, an expression which seems to 

 show that this was the assumption that most annoyed him. 

 Again, in his later attacks on Newton, which were not 

 published till after bin Theory of Colour was completed, 

 he rather strives to show that Newton's facts might be 

 explained on his own hypothesis, and that therefore 

 Newton's hypothesis was not fully proved, than attempts 

 to prove that hypothesis inconsistent with itself or with 

 the facts. Nay, he seems to consider the obviousness of 

 his own hypothesis so overwhelming, that it need only be 

 brought forward to upset Newton's entirely. There are 

 only a few passages where he disputes the experiments 

 described by Newton. Some of them, apparently, he could 

 not succeed in refuting, because the result is not equally 

 easy to observe in all positions of the lenses used, and 

 because he was unacquainted with the geometrical rela- 

 tions by which the most favourable positions of them are 

 determined. In other experiments on the separation of 

 simple coloured light by means of prisms alone, Groethe's 

 objections are not quite groundless, inasmuch as the isola- 

 tion of single colours cannot by this means be so effectu- 

 ally carried out, that after refraction through another 

 prism there are no traces of other tints at the edges. A 

 complete isolation of light of one colour can only be 

 effected by very carefully arranged apparatus, consisting 

 of combined prisms and lenses, a set of experiments which 

 Groethe postponed to a supplement, and finally left un- 

 noticed. When he complains of the complication of 

 these contrivances, we need only think of the laborious 



