Page:The wonders of optics (1869).djvu/92

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CHAPTER II.

THE SOLAR SPECTRUM.


The white light that the glorious orb of day spreads over the face of nature is the original source of all those brilliant and sombre colours with which the works of the Creator are beautified. To the rays of the sun we owe not only the whiteness of the lily, but the scarlet of the field poppy, the modest blue of the timid violet, the splendour of the peacock's plumage, the cool green of the meadows, and the purple and gold of the distant mountains. For, as we have hinted before, this white light, which seems of itself so destitute of colour, is productive of every hue that the eye of man is capable of appreciating.

It may seem that I am bestowing too much praise upon our own sun; but if you are surprised that I should seek to exalt this brilliant globe of ever-burning fire, I must ask you to recollect, that though the starry heavens are full of suns as vast and important as ours, and possibly affording brilliant colourless light to worlds full of inhabitants, there are others that give forth rays that are far from being white. Some are as green as emeralds, others are as blue as sapphires, while others give out a warm light like a ruby or topaz. The worlds which surround these can only receive light of a certain colour, or at any rate they are restricted to a few shades and hues. Imagine living in a world where everything