PRINCIPLES OF COLOR. 



25 



The scope of the present work will not allow an ex- 

 tended dissertation on this subject, the aim being to fur- 

 nish the student with a convenient means of identifying 

 or determining those colors regarding which he may be 

 more or less uncertain. It is obviously impracticable to 

 illustrate all the numerous hues, shades, and tints which 

 occur in the plumage of birds ; but it is believed that the 

 carefully selected assortment depicted on plates II. to X. 

 will answer every reasonable requirement. A great diffi- 

 culty has been encountered in the arrangement of the 

 colors on the plates, from the circumstance that a linear 

 series, which shall express all the relations, gradations, and 

 transitions, is here quite as impossible as in zoological or 

 botanical classifications. Thus, all the purples have more 

 or less of blue and red in their composition ; but some of 

 them through the admixture of yellow or gray (black and 

 white) tend more or less toward brown or gray ; any other 

 series of compound colors presenting equally perplexing 



the light ; which is unfortunate, since in this color we have almost the 

 exact red of the solar spectrum, and can therefore produce by its combina- 

 tion with the purest yellow (light cadmium) and blue (ultramarine), 

 purer orange and purple tints than can be obtained by the use of any 

 other red. Genuine ultramarine is said to be the most perfect of known 

 pigments, and the same may be said of the lighter cadmium-yellows ; so 

 that the great desideratum is a perfect red. Among trustworthy pigments, 

 vermilion, Paris green, and ultramarine are named by Von Bezold (p. 136) 

 as those which most nearly represent the primary colors. However, while 

 the two latter are probably as pure as it will be possible to obtain, the 

 first is very far from a perfect red, making neither a pure orange with 

 yellow nor a purple with any blue. 



Speaking of this matter, a writer in the " Art Union " (we make the 

 quotation at second hand, from the "Art Interchange," vol. xii. no. 13, 

 p. 148) makes the following observations: "We have a good supply of 

 yellows of every shade, some of them quite durable ; we are pretty well 

 furnished with blues, but good reds are very few. The reds of iron 

 [Venetian red, light red, etc.] are too dull, the madder preparations are 

 too weak. Vermilion is excellent in its place, but there is absolutely 

 no true red of good body and quite durable." 



