Peacock feathers

The diffraction of light that occurs in natural phenomena such as rainbows, peacock feathers, certain insects, and the colors that appear on the surfaces of some metals during heating are persistent motifs within a particular stage of the alchemical opus. The cauda pavonis (the peacock s tail) is the brief stage that heralds the final... 

Chapter 8 (which can be covered before Chapter 7 if desired) provides a very broad overview of molecular spectroscopy and the origins of color. The topics range all the way from rainbows and peacock feathers to microwave ovens and the greenhouse effect. Once again, the emphasis is on obtaining an understanding of how we know what we know about molecules, with mathematics kept to a minimum in most sections. 

The iMod type based on biomimetics reflects light using the principle of a photraiic crystal, imitating butterfly wings or peacock feathers... 

There were never any velvet suits or Fauntleroy collars, no lilies or peacock feathers in Bloomsbury (although the Omega Workshops - established by Fry in 1913 - seem to have inspired a distinctive form of female attire) and there was no medievalism either. 

Figure 16.5 Tip of a peacock feather showing colors produced by combined interference and pigmenting.

Nature seems to have developed nacre mainly for its mechanical strength, whereas the attractive optical appearance is only a side effect. In other cases it is really the look that matters. Brilliant color effects can be seen, for example, on butterfly wings or peacock feathers, as shown in Figure 16.5. In these cases, optical interference is often combined with pigments to maximize the effect [9]. Strength of peacock feathers may appear to be a side effect here, but is also important [10]... 

Figure 7.7 Biomimetics of structural colors on silk fabrics, (a) The structure colors of butterfly [Papilio Ulysses butterfly) and peacock feather, (b) Fabrication of opal and inverse opal on silk fabrics. Refer to [103] for the details of fabrication, (c) Structurally colored silk fabrics. Controlled colloidal...

I believe in art for art s sake. It is an unfashionable belief, and some of my statements must be of the nature of an apology. Sixty years ago I should have faced you with more confidence. A writer or a speaker who chose Art for Art s Sake for his theme sixty years ago could be sure of being in the swim, and could feel so confident of success that he sometimes dressed himself in aesthetic costumes suitable to the occasion - in an embroidered dressing-gown, perhaps, or a blue velvet suit with a Lord Fauntleroy collar or a toga, or a kimono, and carried a poppy or a lily or a long peacock s feather in his medieval hand. 

The same unexpected digression from the rule appears in the finery of the provincial ladies Everything is proper everything is well thought out but suddenly some kind of headdress never seen on earth stuck out, or even some kind of feather, almost a peacock s, against all fashion.. . . But of course one couldn t get by without that such is the nature of a provincial city Somewhere it has got to fall on its face. ... 

FIGURE 17.16 A peacock with albinism does not produce the melanin needed to make the bright colors of its feathers. 

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