A PERUSAL of the articles which have appeared in your journal on this subject (NATURE, vol. lxxxiii., pp. 48, 68, 188, 487, and vol. lxxxiv., p. 87) leads me to ask if the spectrum of water has ever ...

People love the rainbow of ROYGBIV colors: red, orange, yellow, green, blue, indigo and violet. Human eyes perceive visible light as this array of colors. You may notice that some colors you can ...

ACCORDING to Mr. Willmer's original hypothesis, a simultaneous stimulation of the rod elements and cone elements produces the various shades of green, yellow and orange which are found in the visible ...

QUESTION: Which animal can see the widest spectrum of colours? Mantis shrimp have remarkable colour vision. They have as many ...