20 



disagrees with the spectroscopic theory concerning the tak- 

 ing of prismatic colors as tests of elementary essence, bnt 

 also qualifies the emission theory, and the theory of color 

 which this is said to represent. It clearly appears that 

 Newton understood and a[)preciated the undulatory theory 

 as a transmitting, if not a creating power. Neither he 

 nor his predecessors declared light composed of colors, 

 but called rays of light color mahers, through prismatic 

 refraction and reflection ; colors never appearing until 

 rays were thrown through and were refracted by prisms 

 or lenses, thereby creating the color, according to the 

 angle of refraction, separating the rays unequally and ad- 

 mitting plates of atmosphere between. Various extracts 

 from his well known work on "Optics" distinctly prove 

 that "emission" and "cor[)uscle" are not used in the sense 

 generally attributed to him, and it does not appear that 

 he contradicted or denied the undulatory theory as a 

 transmitli)ig power. He often referred to the condition 

 of the atmosphere or ether of space, as trembling, wav- 

 ing, etc., so that the rays arc transmitted, as sounds are, 

 by waves or undulations ; and further, implied that colors 

 may not be created, by any original principle of sun 

 rays other than their mere flexibility or refrangibility. 

 This need not be coimected with color as an original 

 principle, though the atmospheric plates, falling between 

 the deflected rays may create color by irregular over and 

 under lappings of shaded lines. It cannot be denied that 

 Newton, though understanding the present undulatory 

 theory, did not credit it with being the origin, but only 

 the vehicle of light. 



Many, since the day of Newton, have worked assiduously 

 in the held of optics and color; prominent among these is 

 Goethe, whose elaborate work was not fully appreciated. 

 His mistakes in quoting Newton come from the inadver- 



