Manufacturer and builder 8 tai 9, 1869
One of the obscure points of science is the cause of the harmony of colors always observed in flowers. When two colors are found, they are generally complements of each other. The wild asters of autumn generally have purple rays and yellow disk flowers. The pansy is yellow and purple, and the blue violet has its stamens yellow and its petals a reddish blue. In fact, yellows and purple generally go together in flowers. A splendid example is afforded by the large Iris Gemarica, the popular flower-de-duce of our gardens. Prone the white base of its petals the colorless sap passes into the petals, which become of a gorgeous purple, while the beard of the petals becomes at the tip of a very rich yellow, though the lower part of each separate filament is not of the purest white. What chemical or physical law determines the arrangement of color, if there be any such secondary cause, is not yet discovered. Two French chemists, Fremy and Clow, say that the tints of flowers are due to cyanin, xanthin, and xanthein. Cyanin is a vegetable blue, which is reddened by acids. A supply of vegetable acid developed in a flower would then turn the blue to rose color, while a scarcely sensible quantity might produce a purple. Xanthin is a yellow from the sun-flower, and xanthein the yellow of ties dahlia. There probably are other coloring substances.
-Ex.
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