There is a fairy story that I read many, many years ago that has never ceased to haunt me.

It told how a little boy once climbed a rainbow.

And at the end of the rainbow, just behind the clouds, he found a wondrous city.

Its houses were of gold, and its streets were paved with silver, and the light that shone upon it was as the light that lies upon the sleeping world at dawn.

In this city there were palaces so beautiful that merely to look upon them satisfied all desires; temples so perfect that they who once knelt therein were cleansed of sin.