If we had to pay a rupee to see a sunset, we might think it was worth looking at. But as sunsets are to be seen free, few people stop to look at them, though they are much more wonderful and beautiful than the scenes in a theatre or the pictures in a cinema, which people rush and pay to see. For if we see beautiful things constantly, we, at last, cease to see them, though we may stop to stare at something that can be seen only very seldom. So people who do not turn their heads to look at the moon or a sunset, or get out of bed to see the dawn, will run to look at a comet, and stop to stare at a rainbow. What I mean is, with most people a thing must be either rare or dear, before they will bother to see it.
It is true that we have not to pay to see a rainbow, but rainbows do not come very often, and so they are uncommon enough to make us stare at one when we see it. And a rainbow is well worth staring at, for it is a very beautiful sight. It appears in the sky when the sun is shining and it is raining; and is a perfect arc or half-circle of light of lovely colours. When it appears, someone is sure to cry out with pleasure and wonder, “O look! there is a rainbow.” And we do look at it until, as the rain stops or the sun is hidden by a cloud, the rainbow fades away. A great English poet, called Words-worth, has a beautiful poem about the rainbow, beginning
“My heart leaps up when I behold A rainbow in the sky”.
What is a rainbow? Well, if we take a piece of three-sided glass or crystal (called a prism) and let a beam of light shine through it, we will see the light come out at the other side in many colours. For a beam of white light is really made up of seven colours – violet, indigo, blue, green, yellow, orange and red. The prism splits the white light into these seven different rays of light. Now the drops of rain as they fall do the same thing as the prism does, and split the white sunlight up into the seven colours, which appear as the beautiful rainbow. That is why we can never see a rainbow unless it is raining when the sun is shining, and why it fades away when the rain stops.
The rainbow is the sign of hope. Perhaps people think of it in this way because a rainbow generally appears towards the end of a shower of rain, and tells them that the rain is nearly over and it will soon be fine again.