“Nature’s resplendent robe! Without whose vesting beauty all were wrapt In unessential gloom.” All colors are rays of light differently reflected. The cause of their diversity was first rationally accounted for by Sir Isaac Newton. He has shown that color is not a specific property of bodies, but is caused by the different rays of light being reflected from the surface of the body; the rest of the rays passing into or through the body. He discovered that in the rays of light are all the colors in nature; and the primary colors he considered to be seven in number, namely, red, orange, yellow, green, blue, indigo and violet; and that bodies appear of different colors, as they have the property of reflecting some rays more powerfully than others. These colors are poetically enumerated by Thomson. “First the flaming _red_ Sprung vivid forth; the tawny _orange_ next; And next delicious _yellow_; by whose side Fell the kind beams of all-refreshing _green_: Then the pure _blue_, that swells autumnal skies, Ethereal play’d; and then, of sadder hue, Emerg’d the deepen’d _indigo_, as when The heavy-skirted evening droops with frost; While the last gleamings of refracted light Dy’d in the fainting _violet_ away.” Since the time of this justly celebrated philosopher, it has been objected, that the seven colors above mentioned are not primitive. It seems very obvious that there can be only three primitive colors, namely, red, yellow, and blue; since all the colors can be made by means of these. It has lately been advanced by Prieur, that the primitive colors are violet, green, and red; that the yellow is formed with red and green, the latter being in excess; and that when the red is in excess, they form orange; the green and violet form blue. The colors excited by the different refrangible rays do not appear to determine what are the primitive colors, since we find that different rays are capable of producing the same color, as a mixture of the yellow with the red produces orange. And it must be admitted, that the violet rays excite, in some degree, the idea of red along with the blue; as in the green, the yellow and blue may be discerned, but none of the red. When the different colored rays are mixed together, either by recomposition, or by getting each color by a separate Spectrum, the result will be white light. Hence Sir Isaac Newton concluded, that when the rays are promiscuously reflected from any surface it will appear white. He also found, and the discovery has since been confirmed by the experiments of Dr. Herschell, that the different colored rays have not by any means the same illuminating power. The violet rays appear to have the least luminous effect, the indigo more, the blue a little more, the green very great, between the green and the yellow the greatest of all, the yellow the same as the green, and the red less