The Promise

Throughout the different writings scattered about many of humankind's civilisations, there appears, in one form or another, an account of a great flood in the dim distant past.
In the Judeo-Christian tradition this pops up as what we know as Noah's flood,with the associated story of the building of the Ark and the propogation of the many species which would otherwise have perished. Those species of course, included us humans.
A little known spin-off from the story of course is the rainbow. I'm not going to fly off on the theory of why it should be a rainbow as opposed to anything else, but when Noah inquired of the Lord as to whether such a flood might ever happen in the future he was told to look up for the guarantee that we would never be totally inundated again. Of course when Noah lifted his gaze, he saw a rainbow. This must have been the first rainbow ever seen, otherwise it would not have been a significant token. There again let me not fly off as to the reason/s. Suffice it to say, that every time I see a rainbow, like this one, I am reminded of the story.
Perhaps that promise is the origin of the old legend that at the end of every rainbow there is a hidden pot of gold.